Glucagon-like peptide 1(GLP-1)is secreted from enteroendocrine L cells in response to nutrient ingestion and exhibits insulinotropic properties by stimulating specific G protein-linked receptors(GLP-1Rs)on pancrea...Glucagon-like peptide 1(GLP-1)is secreted from enteroendocrine L cells in response to nutrient ingestion and exhibits insulinotropic properties by stimulating specific G protein-linked receptors(GLP-1Rs)on pancreaticβcells.Several GLP-1 mimetics,such as exenatide(exendin-4(Ex-4)),liraglutide,and lixisenatide,have been developed and approved as treatments for patients with type 2 diabetes.These peptides show bioactiv-ities almost identical to those of GLP- 1 and have a substantially longer plasma half-life than GLP-1 because of their resistance to dipeptidyl peptidase-4, a GLP-1 degrading enzyme.展开更多
For a long time, fermented dairy products have been consumed for human’s nutrition and health. Recently, consumption of whole dairy products, such as full fat yoghurt, has declined due to the awareness of probable ha...For a long time, fermented dairy products have been consumed for human’s nutrition and health. Recently, consumption of whole dairy products, such as full fat yoghurt, has declined due to the awareness of probable harmful effects of fat on consumers’ health, resulting change of market interest in favor of low or non fat dairy products. It is a challenge for food scientists to produce a suitable fat substitute providing the functionality of the missing fat. The present investigation was carried out to examine the effect of 0 to 50% renneted skim milk (RSM) as a fat mimetic upon the physico-chemical, physical, rheological and sensory characteristics of nonfat yoghurt in comparison to control samples (full fat and skim yoghurt). By increasing RSM content, the chemical characteristics (titratable acidity, pH as well as the content of fat and total protein) of yoghurts did not alter except decrease of total solid in sample with 50% RSM. The yoghurts with more content of RSM exhibited higher b*and a* values, while the highest L* value, viscosity, water holding capacity (WHC), firmness and lowest syneresis were found in sample containing 30% RSM. It seems that new interaction in gel network of yoghurts containing RSM, exhibited greater ability to bind water than control skim yoghurt. In addition, probably new bridges between milk proteins (interacting partially hydrolyzed casein with casein) can increase the number of bounds between protein particles leading to lower syneresis. However, excessive RSM content (higher than 30%) did not increase the L* value, viscosity and WHC of samples probably because of too much aggregation of casein. Sensory results revealed that sample containing 30% RSM was exactly alike to full fat yoghurt in terms of overall sensory attributes. New formulation of palatable skim yoghurt was developed using 3% RSM successfully.展开更多
The dimeric dipeptide mimetics of the brain derived neurotrophic factor (BDNF) loops 1 and 4 and nerve growth factor (NGF) loop 4 were designed and synthesized at the Zakusov Research Institute of Pharmacology. There ...The dimeric dipeptide mimetics of the brain derived neurotrophic factor (BDNF) loops 1 and 4 and nerve growth factor (NGF) loop 4 were designed and synthesized at the Zakusov Research Institute of Pharmacology. There are respectively bis-(N-monosuccinyl-L-methionyl-L-serine) heptamethylenediamide(GSB-214), bis-(N-monosuccinyl-L-seryl-L-lysine) hexamethylenediamide (GSB-106) and bis-(N-monosuccinyl-L-glutamyl-L-lysine) hexamethylenediamide (GK-2). All of the ob-tained compounds activated a corresponding specific NGF or BDNF tyrosine kinase receptor (TrkA or TrkB), but had different postreceptor signaling patterns. GSB-106 activated the ERK and AKT, whereas GSB-214 and GK-2 only activated the AKT kinase. Here we report a comparative analysis of neuroprotective activity of these dipeptides in a model of ischemic stroke induced by transient middle cerebral artery occlusion (MCAO). The all three dimeric dipeptides showed a statistically significant decrease of infarct volumes with the treatment beginning 4 hour after surgery. In the experiment with BDNF mimetics, GSB-106 reduced this volume by 66% and GSB-214 by 26%. NGF GK-2 reduced the cerebral infarct volume by 45%. Thus, BDNF mimetic, which activated both the ERK and AKT, and NGF mimetic, which selectively activated PI3K/AKT, showed high neuroprotective efficacy. In addition, we studied neuroprotective effects of GK-2 at the beginning of the treatment 6, 8 and 24 hours after reperfusion. The neuroprotective effect of GK-2 persisted in all these conditions. The effectiveness of GK-2 at a delayed start of administration suggests that the dipeptide has neuroregenerative properties. The results obtained suggest a potential role for the dimeric dipeptide NGF and BDNF mimetics as therapeutic agents useful in the treatment of a stroke.展开更多
In the past decades, enzyme mimetics based on ceria nanoparticles (nanoceria) have been developed as potential substitutes for nature enzymes. The mixed valence states of cerium and the patterns of oxygen vacancies ...In the past decades, enzyme mimetics based on ceria nanoparticles (nanoceria) have been developed as potential substitutes for nature enzymes. The mixed valence states of cerium and the patterns of oxygen vacancies on crystal planes result in different enzyme mimetic activities. In this review we survey the bio-applications of nanoceria-based enzyme mimetics as well as the underlying mechanisms. Factors influencing the enzyme mimetic activities and future perspective of nanoceria-based enzyme mimetics are also addressed.展开更多
Oxidative stress is associated with many acute and chronic inflammatory diseases.Development of nanomaterial-based enzyme mimetics for reactive oxygen species(ROS)scavenging is challenging,but holds great promise for ...Oxidative stress is associated with many acute and chronic inflammatory diseases.Development of nanomaterial-based enzyme mimetics for reactive oxygen species(ROS)scavenging is challenging,but holds great promise for the treatment of inflammatory diseases.Herein,we report the highly ordered manganese dioxide encapsulated selenium-melanin(Se@Me@MnO_(2))nanozyme with high efficiency for intracellular antioxidation and anti-inflammation.The Se@Me@MnO_(2)nanozyme is sequentially fabricated through the radical polymerization and the in-situ oxidation-reduction.In vitro experimental results demonstrated that the Se@Me@MnO_(2) nanozyme exhibits multiple enzyme activities to scavenge ROS,including catalase(CAT),glutathione peroxidase(GPx)and superoxide dismutase(SOD).Mechanism researches illustrated that the Se core possesses GPx-like catalytic activity,the Me and the MnO_(2) possess both the SOD-like and the CAT-like activities.What’s more,due to the stable unpaired electrons existing in the nanozyme,the Se,Me and MnO_(2) provide synergistic and fast electron transfer effect to achieve the quickly scavenging of hydrogen peroxide,hydroxyl radical,and superoxide anion.Further in vivo experimental results showed that this biocompatible nanozyme exhibits cytoprotective effects by resisting ROS-mediated damage,thereby alleviating the inflammation.This multienzyme mimetics is believed to be an excellent ROS scavenger and have a good potential in clinical therapy for ROS-related diseases.展开更多
A simple and efficient colorimetric biosensing for hydrogen peroxide and glucose with peroxidase-like vitamin C(Vc) functionalized Fe3O4 magnetic nanoparticles(Vc/Fe3O4MNPs) as a catalyst is reported. Compared wit...A simple and efficient colorimetric biosensing for hydrogen peroxide and glucose with peroxidase-like vitamin C(Vc) functionalized Fe3O4 magnetic nanoparticles(Vc/Fe3O4MNPs) as a catalyst is reported. Compared with Fe3O4 MNPs and other catalysts, Vc/Fe3O4 MNPs exhibited superior catalytic properties. Kinetic studies indicated that vitamin C incorporated on Fe3O4 MNPs improved the affinity toward H2O2. As low as 0,29 μmol/L H2O2 can be detected with a wide linear range of 0.5-100 μmol/L H2O2; moreover, as low as 0.288 μmol/L glucose can be detected with a linear range of 0.5-25 μmol/L glucose. The detection method was highly sensitive in sensing H2O2 and glucose. The robustness of Vc/Fe3O4 MNPs rendered them suitable for wide ranging applications.展开更多
Since the catalytic activity of most nanozymes is still far lower than the corresponding natural enzymes,there is urgent need to discover novel highly efficient enzyme-like materials.In this work,Co_(3)V_(2)O_(8)with ...Since the catalytic activity of most nanozymes is still far lower than the corresponding natural enzymes,there is urgent need to discover novel highly efficient enzyme-like materials.In this work,Co_(3)V_(2)O_(8)with hollow hexagonal prismatic pencil structures were prepared as novel artificial enzyme mimics.They were then decorated by photo-depositing Ag nanoparticles(Ag NPs)on the surface to further improve its catalytic activities.The Ag NPs decorated Co_(3)V_(2)O_(8)(ACVPs)showed both excellent oxidase-and peroxidase-like catalytic activities.They can oxidize the colorless 3,3’,5,5’-tetramethylbenzidine rapidly to induce a blue change.The enhanced enzyme mimetic activities can be attributed to the surface plasma resonance(SPR)effect of Ag NPs as well as the synergistic catalytic effect between Ag NPs and Co_(3)V_(2)O_(8),accelerating electron transfer and promoting the catalytic process.ACVPs were applied in constructing a colorimetric sensor,validating the occurrence of the Fenton reaction,and disinfection,presenting favorable catalytic performance.The enzyme-like catalytic mechanism was studied,indicating the chief role of⋅O_(2)-radicals in the catalytic process.This work not only discovers a novel functional material with double enzyme mimetic activity but also provides a new insight into exploiting artificial enzyme mimics with highly efficient catalytic ability.展开更多
Cardiovascular diseases(CVDs)are the leading cause of death globally.CVDs are a group of disorders of the heart and blood vessels and include coronary heart disease,cerebrovascular disease and rheumatic heart disease ...Cardiovascular diseases(CVDs)are the leading cause of death globally.CVDs are a group of disorders of the heart and blood vessels and include coronary heart disease,cerebrovascular disease and rheumatic heart disease among other conditions.There are multiple independent risk factors for CVD,including hypertension,age,smoking,insulin resistance,elevated low-density lipoprotein cholesterol(LDL-C)levels,and triglyceride levels.LDL-C levels have traditionally been the target for therapies aimed at reducing CVD risk.High density lipoprotein(HDL)constitutes the only lipoprotein fraction with atheroprotective functions.Early HDL-targeted therapies have focused on increasing HDL-C levels.However,clinical trials have shown that raising HDL-C with niacin failed to achieve CVD reduction.A possible explanation for these findings is that these drugs could interfere with lipid metabolism and cause alterations in HDL structure and composition,leading to loss of functionality.As a result,targeting HDL-C levels would be insufficient to achieve CVD risk reduction,making HDL functionality a more desirable focus for HDL-directed therapies.There are several drugs which show the potential to improve HDL functionality.These drugs include molecules already approved for human use,such as statins and niacin,and particularly,compounds currently undergoing development such as apolipoprotein A-I mimetics and reconstituted HDL preparations.These therapies show promising potential to improve HDL functionality specifically.Future therapeutic strategies should incorporate HDL functionality as a main target of interest.展开更多
Adaptive mesh refinement(AMR)is the art of solving PDEs on a mesh hierarchy with increasing mesh refinement at each level of the hierarchy.Accurate treatment on AMR hierarchies requires accurate prolongation of the so...Adaptive mesh refinement(AMR)is the art of solving PDEs on a mesh hierarchy with increasing mesh refinement at each level of the hierarchy.Accurate treatment on AMR hierarchies requires accurate prolongation of the solution from a coarse mesh to a newly defined finer mesh.For scalar variables,suitably high-order finite volume WENO methods can carry out such a prolongation.However,classes of PDEs,such as computational electrodynamics(CED)and magnetohydrodynamics(MHD),require that vector fields preserve a divergence constraint.The primal variables in such schemes consist of normal components of the vector field that are collocated at the faces of the mesh.As a result,the reconstruction and prolongation strategies for divergence constraint-preserving vector fields are necessarily more intricate.In this paper we present a fourth-order divergence constraint-preserving prolongation strategy that is analytically exact.Extension to higher orders using analytically exact methods is very challenging.To overcome that challenge,a novel WENO-like reconstruction strategy is invented that matches the moments of the vector field in the faces,where the vector field components are collocated.This approach is almost divergence constraint-preserving,therefore,we call it WENO-ADP.To make it exactly divergence constraint-preserving,a touch-up procedure is developed that is based on a constrained least squares(CLSQ)method for restoring the divergence constraint up to machine accuracy.With the touch-up,it is called WENO-ADPT.It is shown that refinement ratios of two and higher can be accommodated.An item of broader interest in this work is that we have also been able to invent very efficient finite volume WENO methods,where the coefficients are very easily obtained and the multidimensional smoothness indicators can be expressed as perfect squares.We demonstrate that the divergence constraint-preserving strategy works at several high orders for divergence-free vector fields as well as vector fields,where the divergence of the vector field has to match a charge density and its higher moments.We also show that our methods overcome the late time instability that has been known to plague adaptive computations in CED.展开更多
Several important PDE systems,like magnetohydrodynamics and computational electrodynamics,are known to support involutions where the divergence of a vector field evolves in divergence-free or divergence constraint-pre...Several important PDE systems,like magnetohydrodynamics and computational electrodynamics,are known to support involutions where the divergence of a vector field evolves in divergence-free or divergence constraint-preserving fashion.Recently,new classes of PDE systems have emerged for hyperelasticity,compressible multiphase flows,so-called firstorder reductions of the Einstein field equations,or a novel first-order hyperbolic reformulation of Schrödinger’s equation,to name a few,where the involution in the PDE supports curl-free or curl constraint-preserving evolution of a vector field.We study the problem of curl constraint-preserving reconstruction as it pertains to the design of mimetic finite volume(FV)WENO-like schemes for PDEs that support a curl-preserving involution.(Some insights into discontinuous Galerkin(DG)schemes are also drawn,though that is not the prime focus of this paper.)This is done for two-and three-dimensional structured mesh problems where we deliver closed form expressions for the reconstruction.The importance of multidimensional Riemann solvers in facilitating the design of such schemes is also documented.In two dimensions,a von Neumann analysis of structure-preserving WENOlike schemes that mimetically satisfy the curl constraints,is also presented.It shows the tremendous value of higher order WENO-like schemes in minimizing dissipation and dispersion for this class of problems.Numerical results are also presented to show that the edge-centered curl-preserving(ECCP)schemes meet their design accuracy.This paper is the first paper that invents non-linearly hybridized curl-preserving reconstruction and integrates it with higher order Godunov philosophy.By its very design,this paper is,therefore,intended to be forward-looking and to set the stage for future work on curl involution-constrained PDEs.展开更多
A mimetic finite difference scheme for the transient heat equation under Robin’s conditions is presented. The scheme uses second order gradient and divergence mimetic operators, on a staggered grid, to approximate th...A mimetic finite difference scheme for the transient heat equation under Robin’s conditions is presented. The scheme uses second order gradient and divergence mimetic operators, on a staggered grid, to approximate the space derivatives. The temporal derivative is replaced by a first order backward difference approximation to obtain an implicit formulation. The resulting scheme contains nonstandard finite difference stencils. An original convergence analysis by the matrix’s method shows that the proposed scheme is unconditionally stable. A comparative study against standard finite difference schemes, based on central difference or first order one side approximations, reveals the advantages of our scheme without being its implementation more expensive or difficult to achieve.展开更多
Diabetes mellitus is one of the common metabolic disorders acquiring around 2.8%of the world's population and is anticipated to cross 5.4%by the year 2025.Since long back herbal medicines have been the highly este...Diabetes mellitus is one of the common metabolic disorders acquiring around 2.8%of the world's population and is anticipated to cross 5.4%by the year 2025.Since long back herbal medicines have been the highly esteemed source of medicine therefore,they have become a growing part of modern,high-tech medicine.In view of the above aspects the present review provides profiles of plants(65 species) with hypoglycaemic properties,available through literature source from various database with proper categorization according to the parts used,mode of reduction in blood glucose(insulinomimetic or insulin secretagugues activity) and active phyloconsliluents having insulin mimetics activity.From the review it was suggested that,plant showing hypoglycemic potential mainly belongs to the family Leguminoseae,Lamiaceae,Liliaceae,Cucurbitaceae, Asteraceae,Moraceae,Rosaceae and Araliaceae.The most active plants are Allium sativum. Gymnema sylvestre,Citrullus colocynthis,Trigonella foenum greacum,Momordica charantia and Ficuts bengalensis.The review describes some new bioactive drugs and isolated compounds from plants such as roseoside,epigallocatechin gallate,beta-pyrazol-1-ylalanine,cinchonain Ib,leucocyandin 3-O-beta-d-galactosyl cellobioside,leucopelargonidin-3- O-alpha-L rhamuoside,glycyrrhetinic acid,dehydrotrametenolic acid,strictinin,isostrictinin,pedunculagin, epicatechin and christinin-A showing significant insulinomimetic and antidiabetic activity with more efficacy than conventional hypoglycaemic agents.Thus,from the review majorly,the antidiabetic activity of medicinal plants is attributed to the presence of polyphenols,flavonoida, terpenoids,coumarins and other constituents which show reduction in blood glucose levels.The review also discusses the management aspect of diabetes mellitus using these plants and their active principles.展开更多
Objective To examine the neuroprotective effects of a novel manganese porphyrin, manganese (Ill) meso-tetrakis (N,N'-diethylimidazolium-2-yl) porphyrin (MnTDM), in the mouse model of Parkinson's disease (PD)...Objective To examine the neuroprotective effects of a novel manganese porphyrin, manganese (Ill) meso-tetrakis (N,N'-diethylimidazolium-2-yl) porphyrin (MnTDM), in the mouse model of Parkinson's disease (PD) induced by paraquat (PQ). Methods Male C57BL / 6 mice were subcutaneously injected with either saline or PQ at 2-day intervals for a total of 10 doses, MnTDM was subcutaneously injected with the PQ 2 h before treatment. Performance on the pole and swim test were measured 7 days after the last injection and animals were sacrificed one day later. Levels of dopamine (DA) and its metabolites in the striatum were measured by high-performance liquid chromatography with an electrochemical detector (HPLC-ECD). Thiobarbituric acid (TBA) method was used to assay the lipid peroxidation product, malondialdehyde (MDA), and the number of tyrosine hydroxylase (TH) positive neurons was estimated using immunohistochemistry. Results Pretreatment with MnTI)M significantly attenuated PQ-impaired behavioral performance, depleted dopamine content in striata, increased MDA, and dopaminergic neuron loss in the substantia nigra. Conclusions Oxidative stress plays an important role in PQ-induced neurotoxicity which can be potentially prevented by manganese porphyrin. These findings also propose a possible therapeutical strategy for neurodegenerative disorders associated with oxidative stress such as PD.展开更多
Diabetes mellitus (DM) is a chronic metabolic disease characterized by hyperglycemia.Type 2 diabetes (T2DM) accounting for 90% of cases globally.The worldwide prevalence of DM is rising dramatically over the last deca...Diabetes mellitus (DM) is a chronic metabolic disease characterized by hyperglycemia.Type 2 diabetes (T2DM) accounting for 90% of cases globally.The worldwide prevalence of DM is rising dramatically over the last decades,from 30 million cases in 1985 to 382 million cases in 2013.It’s estimated that 451 million people had diabetes in 2017.As the pathophysiology was understood over the years,treatment options for diabetes increased.Incretin-based therapy is one of them.Glucagon-like peptide-1 receptor agonist (GLP-1 RA) not only significantly lower glucose level with minimal risk of hypoglycemia but also,they have an important advantage in themanagement of cardiovascular risk and obesity.Thus,we will review here GLP-1 RAsrole in the treatment of diabetes.展开更多
In this work, metal-organic frameworks (MOFs) FJU-21 was synthesized by solvothermal method. The crystal structure of FJU-21 was characterized by XRD and BET and it was applied to the catalytic hydrolysis of bovine se...In this work, metal-organic frameworks (MOFs) FJU-21 was synthesized by solvothermal method. The crystal structure of FJU-21 was characterized by XRD and BET and it was applied to the catalytic hydrolysis of bovine serum albumin. The effects of reaction pH, temperature and reaction time on the catalytic activity of FJU-21 were studied. FJU-21 were found to possess an intrinsic enzyme mimicking activity similar to that found in trypsin. The Michaelis constant (Km) of the artificial protease (0.18 × 10-3 - 0.20 × 10-3 M-1) was about 15-fold lower than that free trypsin (2.7 × 10-3 M-1) and about 3-fold lower than that of soluble Cu(II) oxacyclen (0.54 × 10-3 M-1). The Kcat of FJU-21 is 102 times higher than that of soluble Cu(II) oxacyclen catalysts and, indicating a much higher affinity of BSA for FJU-21 surface. FJU-21 could be reused for eleven times without losing in its activity.展开更多
In this work, metal-organic frameworks (MOFs) Fe-MIL-101 was synthesized by hydrothermal method, and Fe/Fe-MIL-101 with different loadings was prepared. The crystal structure of the Fe/Fe-MIL-101 sample was characteri...In this work, metal-organic frameworks (MOFs) Fe-MIL-101 was synthesized by hydrothermal method, and Fe/Fe-MIL-101 with different loadings was prepared. The crystal structure of the Fe/Fe-MIL-101 sample was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and specific surface area measurement (BET). Fe/Fe-MIL-101 was found to posses an intrinsic enzyme mimicking activity similar to that found in natural horse-radish peroxidase (HRP). The Michaelis constant (Km) of 5% Fe/Fe-MIL-101 with ABTS as the substrate is about 10-fold smaller than Fe-MIL-101 and about 3-fold smaller than HRP, and about 108 times less than that of CuO NPs (Km = 10.28 mM), indicating a much higher affinity for ABTS than HRP and most of the peroxidase mimetics.展开更多
Beneficial effects of dietary energy restriction (DER), including extension of life-span, reduction in cancer risk, anti-cancer effects and decrease in age related neurodegenerative diseases have been well established...Beneficial effects of dietary energy restriction (DER), including extension of life-span, reduction in cancer risk, anti-cancer effects and decrease in age related neurodegenerative diseases have been well established. Given that DER is difficult to implement in humans due to practical constraints, development of energy restriction mimetics (ERMs) is considered as a suitable alternative. Our recent studies have established the anti-tumor effects of the dietary administration of the glycolytic inhibitor 2-deoxy-D-glucose, a potential ERM, an alternative to DER;without any adverse effects on general physiology. Since functioning of the brain is critically dependent on glucose, we investigated the effects of chronic dietary 2-DG administration on the behavioural outcome in mice. Our findings based on a battery of neuro-behavioural tests clearly suggest that the chronic dietary administration of 2-DG that appreciably impairs the process of tumorigenesis has no adverse effect on the cognitive, affective and sensory-motor functions. Together with the maintenance of normal physiology reported by us earlier, these observations strengthen the potential of dietary 2-DG as a safe cancer preventive strategy.展开更多
Various previous studies have found a negative cor-relation between the risk of cardiovascular events and serum high-density lipoprotein(HDL) cholesterol levels. The reverse cholesterol transport, a pathway of choles-...Various previous studies have found a negative cor-relation between the risk of cardiovascular events and serum high-density lipoprotein(HDL) cholesterol levels. The reverse cholesterol transport, a pathway of choles-terol from peripheral tissue to liver which has several potent antiatherogenic properties. For instance, the particles of HDL mediate to transport cholesterol from cells in arterial tissues, particularly from atherosclerotic plaques, to the liver. Both ATP-binding cassette trans-porters(ABC) A1 and ABCG1 are membrane cholesterol transporters and have been implicated in mediating cholesterol effluxes from cells in the presence of HDL and apolipoprotein A-I, a major protein constituent of HDL. Previous studies demonstrated that ABCA1 and ABCG1 or the interaction between ABCA1 and ABCG1 exerted antiatherosclerotic effects. As a therapeutic approach for increasing HDL cholesterol levels, much focus has been placed on increasing HDL cholesterol levels as well as enhancing HDL biochemical functions. HDL therapies that use injections of reconstituted HDL, apoA-I mimetics, or full-length apoA-I have shown dramatic effectiveness. In particular, a novel apoA-I mi-metic peptide, Fukuoka University ApoA-I Mimetic Pep-tide, effectively removes cholesterol via specific ABCA1 and other transporters, such as ABCG1, and has an an-tiatherosclerotic effect by enhancing the biological func-tions of HDL without changing circulating HDL choles-terol levels. Thus, HDL-targeting therapy has significant atheroprotective potential, as it uses lipid transporter-targeting agents, and may prove to be a therapeutic tool for atherosclerotic cardiovascular diseases.展开更多
Oxidative stress contributes to the pathogenesis of neurodegenerative diseases.With the aim to find reagents that reduce oxidative stress,a phage display library was screened for peptides mimicking a2,6-sialyllactose(...Oxidative stress contributes to the pathogenesis of neurodegenerative diseases.With the aim to find reagents that reduce oxidative stress,a phage display library was screened for peptides mimicking a2,6-sialyllactose(6'-SL),which is known to beneficially influence neural functions.Using Sambucus nigra lectin,which specifically binds to 6'-SL,we screened a phage display library and found a peptide comprising identical sequences of 12 amino acids.Mimetic peptide,reverse peptide and scrambled peptide were tested for inhibition of 6'-SL binding to the lectin.Indeed,lectin binding to 6'-SL was inhibited by the most frequently identified mimetic peptide,but not by the reverse or scrambled peptides,showing that this peptide mimics 6'-SL.Functionally,mimetic peptide,but not the reverse or scrambled peptides,increased viability and expression of neural cell adhesion molecule L1 in SK-N-SH human neuroblastoma cells,and promoted survival and neurite outgrowth of cultured mouse cerebellar granule neurons challenged by H_20_2-induced oxidative stress.The combined results indicate that the 6'-SL mimetic peptide promotes neuronal survival and neuritogenesis,thus raising hopes for the treatment of neurodegenerative diseases.This study was approved by the Medical Ethics Committee of Shantou University Medical College,China(approval No.SUMC 2014-004)on February 20,2014.展开更多
基金supported by a Grant-in-aid for Scientific Research from the Ministry of EducationScience+3 种基金Sports and Culture of Japan(grant number:25430056)the fund from Nukada Institute for Medical and Biological ResearchChibaJapan
文摘Glucagon-like peptide 1(GLP-1)is secreted from enteroendocrine L cells in response to nutrient ingestion and exhibits insulinotropic properties by stimulating specific G protein-linked receptors(GLP-1Rs)on pancreaticβcells.Several GLP-1 mimetics,such as exenatide(exendin-4(Ex-4)),liraglutide,and lixisenatide,have been developed and approved as treatments for patients with type 2 diabetes.These peptides show bioactiv-ities almost identical to those of GLP- 1 and have a substantially longer plasma half-life than GLP-1 because of their resistance to dipeptidyl peptidase-4, a GLP-1 degrading enzyme.
文摘For a long time, fermented dairy products have been consumed for human’s nutrition and health. Recently, consumption of whole dairy products, such as full fat yoghurt, has declined due to the awareness of probable harmful effects of fat on consumers’ health, resulting change of market interest in favor of low or non fat dairy products. It is a challenge for food scientists to produce a suitable fat substitute providing the functionality of the missing fat. The present investigation was carried out to examine the effect of 0 to 50% renneted skim milk (RSM) as a fat mimetic upon the physico-chemical, physical, rheological and sensory characteristics of nonfat yoghurt in comparison to control samples (full fat and skim yoghurt). By increasing RSM content, the chemical characteristics (titratable acidity, pH as well as the content of fat and total protein) of yoghurts did not alter except decrease of total solid in sample with 50% RSM. The yoghurts with more content of RSM exhibited higher b*and a* values, while the highest L* value, viscosity, water holding capacity (WHC), firmness and lowest syneresis were found in sample containing 30% RSM. It seems that new interaction in gel network of yoghurts containing RSM, exhibited greater ability to bind water than control skim yoghurt. In addition, probably new bridges between milk proteins (interacting partially hydrolyzed casein with casein) can increase the number of bounds between protein particles leading to lower syneresis. However, excessive RSM content (higher than 30%) did not increase the L* value, viscosity and WHC of samples probably because of too much aggregation of casein. Sensory results revealed that sample containing 30% RSM was exactly alike to full fat yoghurt in terms of overall sensory attributes. New formulation of palatable skim yoghurt was developed using 3% RSM successfully.
文摘The dimeric dipeptide mimetics of the brain derived neurotrophic factor (BDNF) loops 1 and 4 and nerve growth factor (NGF) loop 4 were designed and synthesized at the Zakusov Research Institute of Pharmacology. There are respectively bis-(N-monosuccinyl-L-methionyl-L-serine) heptamethylenediamide(GSB-214), bis-(N-monosuccinyl-L-seryl-L-lysine) hexamethylenediamide (GSB-106) and bis-(N-monosuccinyl-L-glutamyl-L-lysine) hexamethylenediamide (GK-2). All of the ob-tained compounds activated a corresponding specific NGF or BDNF tyrosine kinase receptor (TrkA or TrkB), but had different postreceptor signaling patterns. GSB-106 activated the ERK and AKT, whereas GSB-214 and GK-2 only activated the AKT kinase. Here we report a comparative analysis of neuroprotective activity of these dipeptides in a model of ischemic stroke induced by transient middle cerebral artery occlusion (MCAO). The all three dimeric dipeptides showed a statistically significant decrease of infarct volumes with the treatment beginning 4 hour after surgery. In the experiment with BDNF mimetics, GSB-106 reduced this volume by 66% and GSB-214 by 26%. NGF GK-2 reduced the cerebral infarct volume by 45%. Thus, BDNF mimetic, which activated both the ERK and AKT, and NGF mimetic, which selectively activated PI3K/AKT, showed high neuroprotective efficacy. In addition, we studied neuroprotective effects of GK-2 at the beginning of the treatment 6, 8 and 24 hours after reperfusion. The neuroprotective effect of GK-2 persisted in all these conditions. The effectiveness of GK-2 at a delayed start of administration suggests that the dipeptide has neuroregenerative properties. The results obtained suggest a potential role for the dimeric dipeptide NGF and BDNF mimetics as therapeutic agents useful in the treatment of a stroke.
文摘In the past decades, enzyme mimetics based on ceria nanoparticles (nanoceria) have been developed as potential substitutes for nature enzymes. The mixed valence states of cerium and the patterns of oxygen vacancies on crystal planes result in different enzyme mimetic activities. In this review we survey the bio-applications of nanoceria-based enzyme mimetics as well as the underlying mechanisms. Factors influencing the enzyme mimetic activities and future perspective of nanoceria-based enzyme mimetics are also addressed.
基金supported by the Innovation Zone Project(No.18-163-12-ZT-003-077-01)Health Major Project(Nos.BWS17J028 and AWS16J018)National Natural Science Foundation of China(Nos.81872835,21621003,and 21563010).
文摘Oxidative stress is associated with many acute and chronic inflammatory diseases.Development of nanomaterial-based enzyme mimetics for reactive oxygen species(ROS)scavenging is challenging,but holds great promise for the treatment of inflammatory diseases.Herein,we report the highly ordered manganese dioxide encapsulated selenium-melanin(Se@Me@MnO_(2))nanozyme with high efficiency for intracellular antioxidation and anti-inflammation.The Se@Me@MnO_(2)nanozyme is sequentially fabricated through the radical polymerization and the in-situ oxidation-reduction.In vitro experimental results demonstrated that the Se@Me@MnO_(2) nanozyme exhibits multiple enzyme activities to scavenge ROS,including catalase(CAT),glutathione peroxidase(GPx)and superoxide dismutase(SOD).Mechanism researches illustrated that the Se core possesses GPx-like catalytic activity,the Me and the MnO_(2) possess both the SOD-like and the CAT-like activities.What’s more,due to the stable unpaired electrons existing in the nanozyme,the Se,Me and MnO_(2) provide synergistic and fast electron transfer effect to achieve the quickly scavenging of hydrogen peroxide,hydroxyl radical,and superoxide anion.Further in vivo experimental results showed that this biocompatible nanozyme exhibits cytoprotective effects by resisting ROS-mediated damage,thereby alleviating the inflammation.This multienzyme mimetics is believed to be an excellent ROS scavenger and have a good potential in clinical therapy for ROS-related diseases.
文摘A simple and efficient colorimetric biosensing for hydrogen peroxide and glucose with peroxidase-like vitamin C(Vc) functionalized Fe3O4 magnetic nanoparticles(Vc/Fe3O4MNPs) as a catalyst is reported. Compared with Fe3O4 MNPs and other catalysts, Vc/Fe3O4 MNPs exhibited superior catalytic properties. Kinetic studies indicated that vitamin C incorporated on Fe3O4 MNPs improved the affinity toward H2O2. As low as 0,29 μmol/L H2O2 can be detected with a wide linear range of 0.5-100 μmol/L H2O2; moreover, as low as 0.288 μmol/L glucose can be detected with a linear range of 0.5-25 μmol/L glucose. The detection method was highly sensitive in sensing H2O2 and glucose. The robustness of Vc/Fe3O4 MNPs rendered them suitable for wide ranging applications.
基金supported by National Natural Science Foundation of China(52208272,41706080 and 51702328)the Basic Scientific Fund for National Public Research Institutes of China(2020S02 and 2019Y03)+3 种基金the Basic Frontier Science Research Program of Chinese Academy of Sciences(ZDBS-LY-DQC025)the Young Elite Scientists Sponsorship Program by CAST(No.YESS20210201)the Strategic Leading Science&Technology Program of the Chinese Academy of Sciences(XDA13040403)the Key Research and Development Program of Shandong Province(Major Scientific and Technological Innovation Project)(2019JZZY020711).
文摘Since the catalytic activity of most nanozymes is still far lower than the corresponding natural enzymes,there is urgent need to discover novel highly efficient enzyme-like materials.In this work,Co_(3)V_(2)O_(8)with hollow hexagonal prismatic pencil structures were prepared as novel artificial enzyme mimics.They were then decorated by photo-depositing Ag nanoparticles(Ag NPs)on the surface to further improve its catalytic activities.The Ag NPs decorated Co_(3)V_(2)O_(8)(ACVPs)showed both excellent oxidase-and peroxidase-like catalytic activities.They can oxidize the colorless 3,3’,5,5’-tetramethylbenzidine rapidly to induce a blue change.The enhanced enzyme mimetic activities can be attributed to the surface plasma resonance(SPR)effect of Ag NPs as well as the synergistic catalytic effect between Ag NPs and Co_(3)V_(2)O_(8),accelerating electron transfer and promoting the catalytic process.ACVPs were applied in constructing a colorimetric sensor,validating the occurrence of the Fenton reaction,and disinfection,presenting favorable catalytic performance.The enzyme-like catalytic mechanism was studied,indicating the chief role of⋅O_(2)-radicals in the catalytic process.This work not only discovers a novel functional material with double enzyme mimetic activity but also provides a new insight into exploiting artificial enzyme mimics with highly efficient catalytic ability.
文摘Cardiovascular diseases(CVDs)are the leading cause of death globally.CVDs are a group of disorders of the heart and blood vessels and include coronary heart disease,cerebrovascular disease and rheumatic heart disease among other conditions.There are multiple independent risk factors for CVD,including hypertension,age,smoking,insulin resistance,elevated low-density lipoprotein cholesterol(LDL-C)levels,and triglyceride levels.LDL-C levels have traditionally been the target for therapies aimed at reducing CVD risk.High density lipoprotein(HDL)constitutes the only lipoprotein fraction with atheroprotective functions.Early HDL-targeted therapies have focused on increasing HDL-C levels.However,clinical trials have shown that raising HDL-C with niacin failed to achieve CVD reduction.A possible explanation for these findings is that these drugs could interfere with lipid metabolism and cause alterations in HDL structure and composition,leading to loss of functionality.As a result,targeting HDL-C levels would be insufficient to achieve CVD risk reduction,making HDL functionality a more desirable focus for HDL-directed therapies.There are several drugs which show the potential to improve HDL functionality.These drugs include molecules already approved for human use,such as statins and niacin,and particularly,compounds currently undergoing development such as apolipoprotein A-I mimetics and reconstituted HDL preparations.These therapies show promising potential to improve HDL functionality specifically.Future therapeutic strategies should incorporate HDL functionality as a main target of interest.
基金DSB acknowledges support via NSF grants NSF-19-04774,NSF-AST-2009776NASA-2020–1241.
文摘Adaptive mesh refinement(AMR)is the art of solving PDEs on a mesh hierarchy with increasing mesh refinement at each level of the hierarchy.Accurate treatment on AMR hierarchies requires accurate prolongation of the solution from a coarse mesh to a newly defined finer mesh.For scalar variables,suitably high-order finite volume WENO methods can carry out such a prolongation.However,classes of PDEs,such as computational electrodynamics(CED)and magnetohydrodynamics(MHD),require that vector fields preserve a divergence constraint.The primal variables in such schemes consist of normal components of the vector field that are collocated at the faces of the mesh.As a result,the reconstruction and prolongation strategies for divergence constraint-preserving vector fields are necessarily more intricate.In this paper we present a fourth-order divergence constraint-preserving prolongation strategy that is analytically exact.Extension to higher orders using analytically exact methods is very challenging.To overcome that challenge,a novel WENO-like reconstruction strategy is invented that matches the moments of the vector field in the faces,where the vector field components are collocated.This approach is almost divergence constraint-preserving,therefore,we call it WENO-ADP.To make it exactly divergence constraint-preserving,a touch-up procedure is developed that is based on a constrained least squares(CLSQ)method for restoring the divergence constraint up to machine accuracy.With the touch-up,it is called WENO-ADPT.It is shown that refinement ratios of two and higher can be accommodated.An item of broader interest in this work is that we have also been able to invent very efficient finite volume WENO methods,where the coefficients are very easily obtained and the multidimensional smoothness indicators can be expressed as perfect squares.We demonstrate that the divergence constraint-preserving strategy works at several high orders for divergence-free vector fields as well as vector fields,where the divergence of the vector field has to match a charge density and its higher moments.We also show that our methods overcome the late time instability that has been known to plague adaptive computations in CED.
基金Dinshaw S.Balsara acknowledges support via NSF grants NSF-19-04774,NSFAST-2009776 and NASA-2020-1241Michael Dumbser acknowledges the financial support received from the Italian Ministry of Education,University and Research(MIUR)in the frame of the Departments of Excellence Initiative 2018-2022 attributed to DICAM of the University of Trento(grant L.232/2016)and in the frame of the PRIN 2017 project Innovative numerical methods for evolutionary partial differential equations and applications.
文摘Several important PDE systems,like magnetohydrodynamics and computational electrodynamics,are known to support involutions where the divergence of a vector field evolves in divergence-free or divergence constraint-preserving fashion.Recently,new classes of PDE systems have emerged for hyperelasticity,compressible multiphase flows,so-called firstorder reductions of the Einstein field equations,or a novel first-order hyperbolic reformulation of Schrödinger’s equation,to name a few,where the involution in the PDE supports curl-free or curl constraint-preserving evolution of a vector field.We study the problem of curl constraint-preserving reconstruction as it pertains to the design of mimetic finite volume(FV)WENO-like schemes for PDEs that support a curl-preserving involution.(Some insights into discontinuous Galerkin(DG)schemes are also drawn,though that is not the prime focus of this paper.)This is done for two-and three-dimensional structured mesh problems where we deliver closed form expressions for the reconstruction.The importance of multidimensional Riemann solvers in facilitating the design of such schemes is also documented.In two dimensions,a von Neumann analysis of structure-preserving WENOlike schemes that mimetically satisfy the curl constraints,is also presented.It shows the tremendous value of higher order WENO-like schemes in minimizing dissipation and dispersion for this class of problems.Numerical results are also presented to show that the edge-centered curl-preserving(ECCP)schemes meet their design accuracy.This paper is the first paper that invents non-linearly hybridized curl-preserving reconstruction and integrates it with higher order Godunov philosophy.By its very design,this paper is,therefore,intended to be forward-looking and to set the stage for future work on curl involution-constrained PDEs.
文摘A mimetic finite difference scheme for the transient heat equation under Robin’s conditions is presented. The scheme uses second order gradient and divergence mimetic operators, on a staggered grid, to approximate the space derivatives. The temporal derivative is replaced by a first order backward difference approximation to obtain an implicit formulation. The resulting scheme contains nonstandard finite difference stencils. An original convergence analysis by the matrix’s method shows that the proposed scheme is unconditionally stable. A comparative study against standard finite difference schemes, based on central difference or first order one side approximations, reveals the advantages of our scheme without being its implementation more expensive or difficult to achieve.
基金financially supported by University Grants Commission,New Delhi
文摘Diabetes mellitus is one of the common metabolic disorders acquiring around 2.8%of the world's population and is anticipated to cross 5.4%by the year 2025.Since long back herbal medicines have been the highly esteemed source of medicine therefore,they have become a growing part of modern,high-tech medicine.In view of the above aspects the present review provides profiles of plants(65 species) with hypoglycaemic properties,available through literature source from various database with proper categorization according to the parts used,mode of reduction in blood glucose(insulinomimetic or insulin secretagugues activity) and active phyloconsliluents having insulin mimetics activity.From the review it was suggested that,plant showing hypoglycemic potential mainly belongs to the family Leguminoseae,Lamiaceae,Liliaceae,Cucurbitaceae, Asteraceae,Moraceae,Rosaceae and Araliaceae.The most active plants are Allium sativum. Gymnema sylvestre,Citrullus colocynthis,Trigonella foenum greacum,Momordica charantia and Ficuts bengalensis.The review describes some new bioactive drugs and isolated compounds from plants such as roseoside,epigallocatechin gallate,beta-pyrazol-1-ylalanine,cinchonain Ib,leucocyandin 3-O-beta-d-galactosyl cellobioside,leucopelargonidin-3- O-alpha-L rhamuoside,glycyrrhetinic acid,dehydrotrametenolic acid,strictinin,isostrictinin,pedunculagin, epicatechin and christinin-A showing significant insulinomimetic and antidiabetic activity with more efficacy than conventional hypoglycaemic agents.Thus,from the review majorly,the antidiabetic activity of medicinal plants is attributed to the presence of polyphenols,flavonoida, terpenoids,coumarins and other constituents which show reduction in blood glucose levels.The review also discusses the management aspect of diabetes mellitus using these plants and their active principles.
文摘Objective To examine the neuroprotective effects of a novel manganese porphyrin, manganese (Ill) meso-tetrakis (N,N'-diethylimidazolium-2-yl) porphyrin (MnTDM), in the mouse model of Parkinson's disease (PD) induced by paraquat (PQ). Methods Male C57BL / 6 mice were subcutaneously injected with either saline or PQ at 2-day intervals for a total of 10 doses, MnTDM was subcutaneously injected with the PQ 2 h before treatment. Performance on the pole and swim test were measured 7 days after the last injection and animals were sacrificed one day later. Levels of dopamine (DA) and its metabolites in the striatum were measured by high-performance liquid chromatography with an electrochemical detector (HPLC-ECD). Thiobarbituric acid (TBA) method was used to assay the lipid peroxidation product, malondialdehyde (MDA), and the number of tyrosine hydroxylase (TH) positive neurons was estimated using immunohistochemistry. Results Pretreatment with MnTI)M significantly attenuated PQ-impaired behavioral performance, depleted dopamine content in striata, increased MDA, and dopaminergic neuron loss in the substantia nigra. Conclusions Oxidative stress plays an important role in PQ-induced neurotoxicity which can be potentially prevented by manganese porphyrin. These findings also propose a possible therapeutical strategy for neurodegenerative disorders associated with oxidative stress such as PD.
文摘Diabetes mellitus (DM) is a chronic metabolic disease characterized by hyperglycemia.Type 2 diabetes (T2DM) accounting for 90% of cases globally.The worldwide prevalence of DM is rising dramatically over the last decades,from 30 million cases in 1985 to 382 million cases in 2013.It’s estimated that 451 million people had diabetes in 2017.As the pathophysiology was understood over the years,treatment options for diabetes increased.Incretin-based therapy is one of them.Glucagon-like peptide-1 receptor agonist (GLP-1 RA) not only significantly lower glucose level with minimal risk of hypoglycemia but also,they have an important advantage in themanagement of cardiovascular risk and obesity.Thus,we will review here GLP-1 RAsrole in the treatment of diabetes.
文摘In this work, metal-organic frameworks (MOFs) FJU-21 was synthesized by solvothermal method. The crystal structure of FJU-21 was characterized by XRD and BET and it was applied to the catalytic hydrolysis of bovine serum albumin. The effects of reaction pH, temperature and reaction time on the catalytic activity of FJU-21 were studied. FJU-21 were found to possess an intrinsic enzyme mimicking activity similar to that found in trypsin. The Michaelis constant (Km) of the artificial protease (0.18 × 10-3 - 0.20 × 10-3 M-1) was about 15-fold lower than that free trypsin (2.7 × 10-3 M-1) and about 3-fold lower than that of soluble Cu(II) oxacyclen (0.54 × 10-3 M-1). The Kcat of FJU-21 is 102 times higher than that of soluble Cu(II) oxacyclen catalysts and, indicating a much higher affinity of BSA for FJU-21 surface. FJU-21 could be reused for eleven times without losing in its activity.
文摘In this work, metal-organic frameworks (MOFs) Fe-MIL-101 was synthesized by hydrothermal method, and Fe/Fe-MIL-101 with different loadings was prepared. The crystal structure of the Fe/Fe-MIL-101 sample was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and specific surface area measurement (BET). Fe/Fe-MIL-101 was found to posses an intrinsic enzyme mimicking activity similar to that found in natural horse-radish peroxidase (HRP). The Michaelis constant (Km) of 5% Fe/Fe-MIL-101 with ABTS as the substrate is about 10-fold smaller than Fe-MIL-101 and about 3-fold smaller than HRP, and about 108 times less than that of CuO NPs (Km = 10.28 mM), indicating a much higher affinity for ABTS than HRP and most of the peroxidase mimetics.
文摘Beneficial effects of dietary energy restriction (DER), including extension of life-span, reduction in cancer risk, anti-cancer effects and decrease in age related neurodegenerative diseases have been well established. Given that DER is difficult to implement in humans due to practical constraints, development of energy restriction mimetics (ERMs) is considered as a suitable alternative. Our recent studies have established the anti-tumor effects of the dietary administration of the glycolytic inhibitor 2-deoxy-D-glucose, a potential ERM, an alternative to DER;without any adverse effects on general physiology. Since functioning of the brain is critically dependent on glucose, we investigated the effects of chronic dietary 2-DG administration on the behavioural outcome in mice. Our findings based on a battery of neuro-behavioural tests clearly suggest that the chronic dietary administration of 2-DG that appreciably impairs the process of tumorigenesis has no adverse effect on the cognitive, affective and sensory-motor functions. Together with the maintenance of normal physiology reported by us earlier, these observations strengthen the potential of dietary 2-DG as a safe cancer preventive strategy.
文摘Various previous studies have found a negative cor-relation between the risk of cardiovascular events and serum high-density lipoprotein(HDL) cholesterol levels. The reverse cholesterol transport, a pathway of choles-terol from peripheral tissue to liver which has several potent antiatherogenic properties. For instance, the particles of HDL mediate to transport cholesterol from cells in arterial tissues, particularly from atherosclerotic plaques, to the liver. Both ATP-binding cassette trans-porters(ABC) A1 and ABCG1 are membrane cholesterol transporters and have been implicated in mediating cholesterol effluxes from cells in the presence of HDL and apolipoprotein A-I, a major protein constituent of HDL. Previous studies demonstrated that ABCA1 and ABCG1 or the interaction between ABCA1 and ABCG1 exerted antiatherosclerotic effects. As a therapeutic approach for increasing HDL cholesterol levels, much focus has been placed on increasing HDL cholesterol levels as well as enhancing HDL biochemical functions. HDL therapies that use injections of reconstituted HDL, apoA-I mimetics, or full-length apoA-I have shown dramatic effectiveness. In particular, a novel apoA-I mi-metic peptide, Fukuoka University ApoA-I Mimetic Pep-tide, effectively removes cholesterol via specific ABCA1 and other transporters, such as ABCG1, and has an an-tiatherosclerotic effect by enhancing the biological func-tions of HDL without changing circulating HDL choles-terol levels. Thus, HDL-targeting therapy has significant atheroprotective potential, as it uses lipid transporter-targeting agents, and may prove to be a therapeutic tool for atherosclerotic cardiovascular diseases.
基金supported by the National Natural Science Foundation of China,No.81471279 and No.81171138(to WJZ)Talent Support Grant from Shantou University Medical College,China,No.2501220118(to WJZ)the Li Kashing Foundation,No.LD030302(to MS)
文摘Oxidative stress contributes to the pathogenesis of neurodegenerative diseases.With the aim to find reagents that reduce oxidative stress,a phage display library was screened for peptides mimicking a2,6-sialyllactose(6'-SL),which is known to beneficially influence neural functions.Using Sambucus nigra lectin,which specifically binds to 6'-SL,we screened a phage display library and found a peptide comprising identical sequences of 12 amino acids.Mimetic peptide,reverse peptide and scrambled peptide were tested for inhibition of 6'-SL binding to the lectin.Indeed,lectin binding to 6'-SL was inhibited by the most frequently identified mimetic peptide,but not by the reverse or scrambled peptides,showing that this peptide mimics 6'-SL.Functionally,mimetic peptide,but not the reverse or scrambled peptides,increased viability and expression of neural cell adhesion molecule L1 in SK-N-SH human neuroblastoma cells,and promoted survival and neurite outgrowth of cultured mouse cerebellar granule neurons challenged by H_20_2-induced oxidative stress.The combined results indicate that the 6'-SL mimetic peptide promotes neuronal survival and neuritogenesis,thus raising hopes for the treatment of neurodegenerative diseases.This study was approved by the Medical Ethics Committee of Shantou University Medical College,China(approval No.SUMC 2014-004)on February 20,2014.