Therapeutic effect of zhuodu theory on ulcerative colitis and its effect on brain-gut peptide in serum and inflammatory factor

Objective:To investigate the therapeutic effect of traditional Chinese medicine xiezhuojiedu decoction on ulcerative colitis(UC)based on zhuodu theory and its effect on serum brain-gut peptide and inflammatory factors.Methods:110 cases of UC patients were divided into 2 groups according to the random number table method,with 55 cases in each group.The control group was treated with mesalazine,and the treatment group was given oral administration of Chinese medicine xiezhuojiedu decoction on the basis of the control group.Both groups received continuous treatment for 8 weeks.Integral of TCM syndromes,serum inflammatory factor and brain-gut peptide before and after treatment were compared between the two groups.The clinical efficiency,mucosal healing rate and endoscopic response rate of the two groups were compared.Results:After treatment,Integral of the main TCM syndromes abdominal pain,diarrhea,abdominal distention,mucous hematochezia,tenesmus of the treatment group were lower than the control group(P<0.01),the levels of serum(Tumor necrosis factor-α,(TNF-α),Interleukin(IL)-33,Substance P(SP)were lower than the control group(P<0.01),the levels of IL-10,vasoactive intestinal peptide(VIP),Somatostatin(SS)were higher than the control group(P<0.01),the clinical efficiency and mucosal healing rate were higher than control group(P<0.05),The difference was statistically significant.Conclusion:Based on the zhuodu theory,the xiezhuojiedu decoction can effectively regulate the levels of inflammatory factor and brain-gut peptide in the treatment of UC,improve the symptoms of patients,and promote the repair of intestinal mucosa.It's effective in treatment.

Neutrophil peptide 1 accelerates the clearance of degenerative axons during Wallerian degeneration by activating macrophages after peripheral nerve crush injury

Macrophages play an important role in peripheral nerve regeneration,but the specific mechanism of regeneration is still unclear.Our preliminary findings indicated that neutrophil peptide 1 is an innate immune peptide closely involved in peripheral nerve regeneration.However,the mechanism by which neutrophil peptide 1 enhances nerve regeneration remains unclear.This study was designed to investigate the relationship between neutrophil peptide 1 and macrophages in vivo and in vitro in peripheral nerve crush injury.The functions of RAW 264.7 cells we re elucidated by Cell Counting Kit-8 assay,flow cytometry,migration assays,phagocytosis assays,immunohistochemistry and enzyme-linked immunosorbent assay.Axonal debris phagocytosis was observed using the CUBIC(Clear,Unobstructed Brain/Body Imaging Cocktails and Computational analysis)optical clearing technique during Wallerian degeneration.Macrophage inflammatory factor expression in different polarization states was detected using a protein chip.The results showed that neutrophil peptide 1 promoted the prolife ration,migration and phagocytosis of macrophages,and CD206 expression on the surfa ce of macrophages,indicating M2 polarization.The axonal debris clearance rate during Wallerian degeneration was enhanced after neutrophil peptide 1 intervention.Neutrophil peptide 1 also downregulated inflammatory factors interleukin-1α,-6,-12,and tumor necrosis factor-αin invo and in vitro.Thus,the results suggest that neutrophil peptide 1 activates macrophages and accelerates Wallerian degeneration,which may be one mechanism by which neutrophil peptide 1 enhances peripheral nerve regeneration.

Effect of amitriptyline on gastrointestinal function and brain-gut peptides: A double-blind trial

AIM: To study the effects of low-dose amitriptyline (AMT) on gastrointestinal function and brain-gut peptides in healthy Chinese volunteers. METHODS: This was a double-blind, randomised, placebo-controlled, two-period cross-over trial. Twentyeight healthy volunteers were randomised and administered 1-wk treatments of AMT (12.5 mg tid) or placebo. Before and during the final two days of treatment, gastric emptying, proximal gastric accommodation and visceral sensitivity were measured by drinkingultrasonography test; the orocecal transit time (OCTT) was measured by lactulose hydrogen breath test, and fasting blood was collected. Plasma levels of ghrelin, motilin and neuropeptide Y (NPY) were measured by enzyme-linked immunosorbent assay kits.RESULTS: AMT slowed the OCTT (109.2 ± 29.68 min vs 96.61 ± 23.9 min, P = 0.004) but did not affect liquid gastric emptying and had no effect on proximal gastric accommodation. AMT resulted in decreases in the visual analogue scale (VAS) for difficulty in drinking 600 and 800 mL of water (3.57 ± 0.94 vs 2.98 ± 0.85, 5.57 ± 0.82 vs 4.57 ± 0.98, P < 0.01 for both), although it had no significant effect on the VAS for difficulty in drinking 200 mL and 400 mL of water. AMT significantly increased the plasma ghrelin level (442.87 ± 176.79 pg/mL vs 526.87 ± 158.44 pg/mL, P = 0.04) and the neuropeptide-Y level (890.15 ± 131.46 pg/mL vs 965.64 ± 165.63 pg/mL, P = 0.03), whereas it had no effect on the MTL level. CONCLUSION: Low-dose AMT could slow OCTT, make the stomach less sensitive and increase the plasma levels of ghrelin and NPY. Thus, we recommend the use of low-dose AMT for functional gastrointestinal disorders.

Effects of L-3-n-butylphthalide on caspase-3 and nuclear factor kappa-B expression in primary basal forebrain and hippocampal cultures after beta-amyloid peptide 1-42 treatment

BACKGROUND： L-3-n-butylphthalide （L-NBP） can inhibit phosphorylation of tau protein and reduce the neurotoxicity of beta-amyloid peptide 1-42 （Aβ1-42）. OBJECTIVE： To observe the neuroprotective effects of L-NBP on caspase-3 and nuclear factor kappa-B （NF- K B） expression in a rat model of Alzheimer＇s disease. DESIGN, TIME AND SETTING： A cell experiment was performed at the Central Laboratory of Provincial Hospital affiliated to Shandong University between January 2008 and August 2008. MATERIALS： L-NBP （purity 〉 98%） was provided by Shijiazhuang Pharma Group NBP Pharmaceutical Company Limited. Aβ1-42, 3-[4,5-dimethylthiazolo-2]-2,5 iphenyltetrazolium bromide （MTT）, and rabbit anti-Caspase-3 polyclonal antibody were provided by Cell Signaling, USA; goat anti-choactase and rabbit anti-NF- kB antibodies were provided by Santa Cruz, USA. METHODS： Primary cultures were generated from rat basal forebrain and hippocampal neurons at 17 or 19 days of gestation. The cells were assigned into five groups： the control group, the Aβ1-42 group （2 μmol/L）, the Aβ1-42 ＋ 0.1 μmol/L L-NBP group, the Aβ1-42 ＋ 1 μ mol/L L-NBP group, and the Aβ1-42 ＋ 10μmol/L L-NBP group. The neurons were treated with Aβ1-42 （2 μmol/L） alone or in combination with L-NBP （0.1, 1, 10 μmol/L） for 48 hours. Cells in the control group were incubated in PBS. MAIN OUTCOME MEASURES： Morphologic changes were evaluated using inverted microscopy, viability using the M-I-I- method, and the changes in caspase-3 and NF- k B expression using Western blot. RESULTS： Induction with Aβ1-42 for 48 hours caused cell death and soma atrophy, and increased caspase-3 and NF- K B expression （P 〈 0.05）. L-NBP blocked these changes in cell morphology, decreased caspase-3 and NF- k B expression （P 〈 0.05）, and improved cell viability, especially at the high dose （P 〈 0.05）. CONCLUSION： AI3^-42 is toxic to basal forebrain and hippocampal primary neurons; L-NBP protects against this toxicity and inhibits the induction of caspase-3 and NF- K B expression.

Study on the regulation of brain-gut peptide by Shenling Baizhu San in functional diarrhea rats

Objective:To explore the therapeutic mechanism of Shenling Baizhu San (SLBZS) on functional diarrhea (FDr) by studying the brain-gut axis and related neuropeptides.Methods:Sixty male Wistar rats were randomly divided into the control group,model group,SLBZS-treated group and Montmorillonite Powder-treated group (MP-treated group) (n =15/group).Rats received gavage after the establishment of functional diarrhea.An equal volume of SLBZS solution and Montmorillonite Powder (MP) solution was administered to the SLBZS-treated group and MP-treated group,respectively,and an equal volume of distilled water was administered to the control group and the model group.The chemical components and targets related to SLBZS were identified from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and Traditional Chinese Medicine Integrated Database (TCMID).The effective chemical components were screened based on oral bioavailability (OB) and drug like-index (DL),and their biological functions were analyzed by GlueGO.Based on this screening,the expression of Cholecystokinin (CCK) and Ghrelin in the hypothalamus of rats was detected by real-time PCR (RT-PCR) and western blotting.Results:In this study,72 effective components and 190 core targets of SLBZS were screened.SLBZS may regulate smooth muscle contraction,energy metabolism and other biological processes.The results of RT-PCR showed that in the model group,the expression of CCK mRNA (P =.001) and Ghrelin mRNA (P =.000) increased significantly.Compared with the model group,CCK mRNA (P =.007) and Ghrelin mRNA (P =.001) levels in SLBZS-treated rats were decreased significantly.The results of western blotting showed that in the model group,the protein expression of CCK (P =.001) and Ghrelin (P =.000) increased significantly.The protein levels of CCK (P =.001) and Ghrelin (P =.005) in the SLBZS-treated group were decreased significantly compared with the model group.Conclusion:SLBZS improved functional diarrhea by regulating the brain-gut axis.Changes in the expressions of brain-gut peptide,CCK and Ghrelin might explain the pathogenesis of functional diarrhea related to brain-gut peptide and gastrointestinal hormone.

Protection of tight junction between RPE cells with tissue factor targeting peptide

AIM：To investigate the effect of tissue factor targeting peptide（TF-TP）on retinal pigment epithelium（RPE）cells tight junctions.METHODS：Cell counting kit-8（CCK-8）was used to measure the proliferation of ARPE-19 cells.Expression of tight junction,ZO-1 in ARPE-19 cells was measured by Western blot and immunofluorescent staining.Western blot was also used to detect the expression of tissue factor（TF）.CEC Transmigration Assay was used to measure the migration of ARPE-19 cells.The transport of fluorescent markers [fluorescein isothiocyanate dextrans of 4,10,20（FD4,FD10,FD20） ]and the transepithelial electrical resistance（TEER）were used to measure in ARPE-19 cell RESULTS：CCK-8 assay showed that 5μmol/L TF-TP can inhibit ARPE-19 cells abnormally proliferation stimulated by lipopolysaccharide（LPS;P〈0.05）.LPS increased the transport of fluorescent markers（FD4,FD10,FD20）and decreased TEER levels in ARPE-19 cells,respectively,which were prevented by 5μmol/L TF-TP pretreatment（P〈0.05）. Furthermore,LPS significantly up-regulated the expression of TF and downregulated the expression of ZO-1（P〈0.05）in ARPE-19 cell which was inhibited by the TF-TP（P〈0.05）.In addition,TF-TP inhibited the abnormal migration induced by LPS in ARPE-19 cell（P〈0.05）.CONCLUSION：Our findings suggest that TF-TP suppressed proliferation and migration of ARPE-19 cells induced by LPS,and maintained the RPE tight junctions through inhibition of TF expression and increased expression of ZO-1.

A peptide chain release factor 2a gene regulates maize kernel development by modulating mitochondrial function

Mitochondrial protein translation that is essential for aerobic energy production includes four essential steps of the mitochondrial ribosome cycle,namely,initiation,elongation,termination of the polypeptide,and ribosome recycling.Translation termination initiates when a stop codon enters the A site of the mitochondrial ribosome where it is recognized by a dedicated peptide release factor(RF).However,RFs and mechanisms involved in translation in plant mitochondria,especially in monocotyledons,remain largely unknown.Here,we identified a crumpled kernel(crk5 allele)mutant,with significantly decreased kernel size,100-kernel weight,and an embryo-lethal phenotype.The Crk5 allele was isolated using map-based cloning and found to encode a mitochondrial localization RF2a.As it is an ortholog of Arabidopsis mitochondrial RF2a,we named the gene ZmmtRF2a.ZmmtRF2a is missing the 5th–7th exons in the crk5 resulting in deletion of domains containing motifs GGQ and SPF that are essential for release activity of RF,mitochondrial ribosome binding,and stop codon recognition.Western blot and qRT-PCR analyses indicate that the crk5 mutation results in abnormal mitochondrion structure and function.Intriguingly,we observed a feedback loop in the crk5 with up-regulated transcript levels detected for several mitochondrial ribosome and mitochondrial-related components,in particular mitochondrial complexes CI,CIV,and a ribosome assembly related PPR.Together,our data support a crucial role for ZmmtRF2a in regulation of mitochondrial structure and function in maize.

PEGylated PLGA Nanoparticles as Tumor Ecrosis Factor-α Receptor Blocking Peptide Carriers:Preparation,Characterization and Release in vitro

To assess the merits of PEGylated poly （lactic-co-glycolic acid） （PEG-PLGA） nanoparticles as drug carriers for tumor necrosis factor-α receptor blocking peptide （TNFR-BP）, PEG-PLGA copolymer, which could be used to prepare the stealth nanoparticles, was synthesized with methoxypolyethyleneglycol, DL-lactide and glycolide. The structure of PEG-PLGA was confirmed with ^1H-NMR and FT-IR spectroscopy, and the molecular weight （MW） was determined by gel permeation chromatography. Fluorescent FITC-TNFR- BP was chosen as model protein and encapsulated within PEG-PLGA nanoparticles using the double emulsion method. Atomic force microscopy and photon correlation spectroscopy were employed to characterize the stealth nanoparticles fabricated for morphology, size with polydispersity index and zeta potential. Encapsulation efficiency （EE） and the release of FITC-TNFR-BP in nanopartieles in vitro were measured by the fluorescence measurement. The stealth nanoparticles were found to have the mean diameter less than 270 nm and zeta potential less than -20 mV. In all nanoparticle formulations, more than 45% of EE were obtained. FITC-TNFR-BP release from the PEG-PLGA nanoparticles exhibited a biphasic pattern, initial burst release and consequently sustained release. The experimental results show that PEG-PLGA nanoparticles possess the potential to develop as drug carriers for controlled release applications of TNFR-BP.

Effect of calcitonin gene-related peptide and nerve growth factor on spatial learning and memory abilities of rats following focal cerebral ischemia/reperfusion

BACKGROUND: Calcitonin gene-related peptide (CGRP) and nerve growth actor (NGF) cam improve spatial learning and memory abilities of rats with cerebral ischemia/reperfusion; however, the effect of combination of them on relieving learning and memory injury following cerebral ischemia/reperfusion should be further studied. OBJECTIVE: To study the effects of exogenous CGRP and NGF on learning and memory abilities of rats with focal cerebral ischemia/reperfusion. DESIGN: Randomized controlled animal study. SETTING: Department of Neurosurgery, the Second Hospital of Xiamen; Department of Neurosurgery, the Second Affiliated Hospital of China Medical University; Department of Neurobiology, Basic Medical College of China Medical University. MATERIALS: A total of 30 healthy male SD rats, aged 8 weeks, of clean grade, weighing 250-300 g, were provided by Experimental Animal Department of China Medical University. All rats were randomly divided into sham-operation group, ischemia/reperfusion group and treatment group with 10 in each group. The main reagents were detailed as the follows: 100 g/L chloral hydrate, 0.5 mL CGRP (2 mg/L, Sigma Company, USA), and NGF (1× 106 U/L, 0.5 mL, Siweite Company, Dalian). METHODS: The experiment was carried out in the Department of Neurobiology, Basic Medical College of China Medical University from February to July 2005. Rat models of middle cerebral artery occlusion were established by method of occlusion, 2 hours after that rats were anesthetized and the thread was slightly drawn out for 10 mm under direct staring to perform reperfusion. Rats in the ischemia/reperfusion group received intraperitoneal injection of 1 mL saline via the abdomen at two hours later, while rats in the treatment group at 2 hours later received intraperitoneal injection of 2 mg/L CGRP (0.5 mL) and 1×106 U/L NGF (0.5 mL) once a day for 10 successive days. First administration was accomplished within 15 minutes after ischemia/reperfusion. Rats in the sham-operation group were separated of the vessels without occlusion or administration. The neural function was evaluated with Zea Longa 5-grade scale. Animals with the score of one, two and three points received Morris water-maze test to measure searching time on platform (omitting platform-escaping latency). Meanwhile, leaning and memory abilities of animals were reflected through testing times of passing through platform per minute. MAIN OUTCOME MEASURES: Experimental results of omitting platform-escaping latency and spatial probe. RESULTS: Three and two rats in the ischemia/reperfusion group and treatment group respectively were not in accordance with the criteria in the process, and the rest were involved in the final analysis. ① Comparisons of platform-escaping latency during Morris water-maze test in all the three groups: Ten days after modeling, the platform-escaping latency in the ischemia/reperfusion group was obviously longer than that in sham-operation group (P < 0.01), and was significantly shorter than that in the treatment group (P < 0.01). ② Comparisons of times of passing through platform in all the three groups: Times of passing through platform were remarkably less in the ischemia/reperfusion group than those in the sham-operation group [(1.79±0.39), (4.30±0.73) times/minute, P < 0.01], and those were markedly more in the treatment group than the ischemia/reperfusion group [(3.16±1.03), (1.79±0.39) times/minute, P < 0.01]. CONCLUSION: CGRP and NGF are capable of ameliorating the abilities of spatial learning and memory in MCAO rats, which indicates that CGRP and NGF can protect ischemic neurons.

Psoriatic arthritis: clinical patterns, rheumatoid factor, anti-cyclic citrullinated peptide and human leukocyte antigen risk alleles

Psoriatic arthritis is an inflammatory arthritis associated with psoriasis.Both rheumatoid factor and anti-cyclic citrullinated peptide antibodies positive psoriatic arthritis patients may be in risk for development of symmetrical polyarthritis pattern.Symmetrical polyarthritis pattern was predominant(42%)among clinical pattern of psoriatic arthritis.Among 10 rheumatoid factor positive patients,8(80%)patients had symmetrical polyarthritis pattern and out of 7 anti-cyclic citrullinated peptide antibody positive patients,7(100%)patients had symmetrical polyarthritis pattern.Association of anti-cyclic citrullinated peptide(P=0.008)and rheumatoid factor(P=0.006)showed statistical significance with symmetrical polyarthritis pattern.Human leukocyte antigen-B*07,*38 and human leukocyte antigen-C*07 were predominantly found in rheumatoid factor and anti-cyclic citrullinated peptide positive psoriatic arthritis patients.Background:Psoriatic arthritis is an inflammatory arthritis associated with psoriasis.It is usually seronegative in nature but a small percentage of patients may be positive for rheumatoid factor and anti-cyclic citrullinated peptide antibodies.Anti-cyclic citrullinated peptide and rheumatoid factor are highly specific for rheumatoid arthritis but their role is not clear in psoriatic arthritis.The prevalence and prognostic value of anti-cyclic citrullinated peptide antibody and rheumatoid factor in psoriatic arthritis patients is not well known.The aim of this study was therefore to investigate the prevalence of anti-cyclic citrullinated peptide antibodies and rheumatoid factor in psoriatic arthritis patients and assess their clinical associations and also to see the distribution of human leukocyte antigen-B and human leukocyte antigen-C locus antigens in anti-cyclic citrullinated peptide antibody and rheumatoid factor positive psoriatic arthritis patients.Methods:Fifty patients with psoriatic arthritis were tested for the presence of rheumatoid factor and anti-cyclic citrullinated peptide antibodies.Polymerase chain reaction was done with sequence specific primer for detection of human leukocyte antigen-B and human leukocyte antigen-C locus antigens in rheumatoid factor and anti-cyclic citrullinated peptide positive psoriatic arthritis patients.Data on five clinical patterns of rheumatological manifestations of psoriatic arthritis patients were collected prospectively on all patients and statistically compared between anti-cyclic citrullinated peptide,rheumatoid factor positive and negative patients by chi-square test.We also see the distribution of human leukocyte antigen-B and human leukocyte antigen-C locus antigens in anti-cyclic citrullinated peptide antibody and rheumatoid factor positive psoriatic arthritis patients.Results:Among 50 psoriatic arthritis patients,rheumatoid arthritis test was positive in 10(20%)patients and anti-cyclic citrullinated peptide was positive in 7(14%)patients.Symmetrical polyarthritis pattern is predominant among clinical pattern of psoriatic arthritis which was found in 21(42%)patients.Among 7 anti-cyclic citrullinated peptide positive psoriatic arthritis patients,symmetrical polyarthritis pattern is predominant and it was found in 7(100%)patients.Among 10 rheumatoid factor positive psoriatic arthritis patients,symmetrical polyarthritis pattern is predominant and it was found in 8(80%)patients.In this study,symmetrical polyarthritis pattern is statistically associated with anti-cyclic citrullinated peptide positive psoriatic arthritis patients(P=0.008)and rheumatoid factor positive psoriatic arthritis patients(P=0.006).Human leukocyte antigen-B*07,*38 and human leukocyte antigen-C*07 were predominantly found in rheumatoid factor and anti-cyclic citrullinated peptide positive psoriatic arthritis patients.Conclusion:Both rheumatoid factor and anti-cyclic citrullinated peptide positive psoriatic arthritis patients may be in risk for development of symmetrical polyarthritis pattern.Among rheumatoid factor and anti-cyclic citrullinated peptide positive psoriatic arthritis patients,Human leukocyte antigen-B*07,*38 and human leukocyte antigen-C*07 alleles were more frequently found alleles.

Effects of compound danshen dripping pills on the levels of serum inflammatory factors, brain natriuretic peptide and blood lipid in CABG postoperative patients

Objective:To explore the effects of compound danshen dripping pills on the levels of serum inflammatory factors,brain natriuretic peptide(BNP)and blood lipid in CABG postoperative patients.Methods:156 cases of patients who were given CABG from January 2015 to January 2018 in Baogang Hospital were chosen and randomly divided into the observation group(n=78)and the control group(n=78).Both groups were given conventional drugs,simultaneously,the observation group was given compound danshen dripping pills.The treatment lasted 3 months.The clinical efficacy was compared between two groups of patients,and the levels of serum inflammatory factors,plasma BNP and blood lipid before and after treatment in two groups of patients were detected in order to make a comparison in the incidence of adverse cardiac events between two groups of patients.Results:After treatment,the total effective rate of treatment in the observation group was significantly higher than that in the control group;in the two groups,the levels of serum interleukin-6(IL-6),interleukin-8(IL-8),C-reactive protein and plasma BNP after treatment were obviously lower than those before treatment,and these indicators in the observation group were lower than those in the control group(p<.05);the levels of TG,TC and LDL-C in two groups were obviously lower(p<.05)with the level of HDL-C significantly higher(all p<.05),and the descending or ascending range of each indicator in the observation group was obviously larger than that in the control group(p<.05);in the follow-up visit,the incidence of adverse cardiac events in the observation group of patients was significantly lower than that in the control group of patients(p<.05).Conclusions:Compound danshen dripping pills can effectively reduce the levels of serum inflammatory factors and BNP,regulate blood lipid metabolism and reduce the incidence of adverse cardiac events in CABG postoperative patients.

Effect of recombinant human brain natriuretic peptide on serum inflammatory factors, neuroendocrine hormones and cardiac function in patients with acute myocardial infarction complicated with heart failure

Objective:To investigate the effect of recombinant human brain natriuretic peptide (BNP) on inflammatory factors, neuroendocrine hormones and cardiac function indexes in patients with acute myocardial infarction complicated with heart failure.Methods:A total of91 cases of acute myocardial infarction with heart failure patients were divided into the control group (n=44) and observation group (n=47) according to the random data table, two groups of patients were given conventional treatment, based on this, the control group was given intravenous infusion of Nitroglycerin Injection treatment, the observation group received intravenous injection of recombinant human brain natriuretic peptide treatment, compared serum inflammatory factors, neuroendocrine hormone and cardiac function and other indexes of two groups before and after treatment.Results: there was no significant difference between the two groups before treatment. After treatment, the levels of TNF-α, hs-CRP, IL-6, MCP-1, LVESD and LVEDD in the two groups were significantly lower than those within the group before treatment, and the observation group was significantly lower than the control group;The two groups after treatment LVEF levels were significantly higher than those in the group before treatment, and the observation group was significantly higher than that of control group;the observation group after treatment PRA, Ang II and ALD and NE levels were significantly lower than those before treatment, and was significantly lower than the control group after treatment, the difference was significant, PRA, Ang, ALD and NE levels of control group before and after the treatment was no significant difference.Conclusion:recombinant human brain natriuretic peptide in the treatment of acute myocardial infarction with heart failure can effectively reduce the serum inflammatory factors and neuroendocrine hormone levels, improve heart function, and have a certain clinical value.

Forskolin Modulates the Inhibitory Effect of C-Type Natriuretic Peptide on Hypoxia-Induced Atrial Dynamics and Hypoxia Inducible Factor 1 Alpha Activity

Our study investigated effects of C-type natriuretic peptide (CNP) on atrial dynamics and hypoxia inducible factor 1 alpha (HIF-1α) activity in perfused beating rat atria, under hypoxic conditions. Hypoxia significantly increased the levels of HIF-1α, concomitant with decreased trial dynamics. CNP (0.1 μmol/L) further decreased atrial dynamics under hypoxia and suppressed hypoxia-induced stimulation of HIF-1α expression. An adenylylcyclase (AC) activator, forskolin (0.1 μmol/L), significantly up-regulated atrial phosphodiesterase subtype 3A (PDE 3A) protein without affecting hypoxia-induced dynamics. In the presence of forskolin, the inhibitory effects of CNP on hypoxia-induced atrial dynamics and HIF-1α levels were significantly attenuated. Forskolin also prevented hypoxia-induced downregulation of PDE3A protein. These findings suggested that CNP inhibited atrial dynamics and HIF-1α activity in the isolated perfused beating rat atria under hypoxic conditions. Furthermore, both effects were modulated by the AC activator forskolin, through activation of CNP-PDE 3A signaling.

Cell-permeable Tat-NBD peptide attenuates rat pancreatitis and acinus cell inflammation response

AIM： To investigate the effects of Tat-NEMO-binding domain （NBD） peptide on taurocholate-induced pancreatitis and lipopolysaccharide （LPS）-stimulated AR42J acinus ceils inflammatory response in rats. METHODS： Sodium taurocholate （5%） was used to induce the pancreatitis model. Forty-eight rats from the taurocholate group received an intravenous bolus of 13 mg/kg Tat-NBD （wild-type, WT） peptide, Tat- NBD （mutant-type, MT） peptide, NBD peptide or Tat peptide. The pancreatic histopathology was analyzed by hematoxylin staining. LPS was added to the culture medium to stimulate the AR42J cells. For pretreatment, cells were incubated with different peptides for 2 h before LPS stimulation. Expression of IL-1β and TNF-α mRNA was analyzed using a semi-quantitative reverse-transcript polymerase chain reaction （RT-PCR） method. IL-1β and TNF-α protein in culture medium were detected by enzyme linked immunosorbent assay （ELISA）. NF-KB DNA-binding in pancreas was examined by electrophoretic mobility shift assays. P65 expression of AR42J was determined by Strept Actividin-Biotin Complex （SABC） method. RESULTS： Pretreatment with Tat-NBD （WT） peptide at a concentration of 13 mg/kg body wt showed beneficial effect in pancreaitis model. LPS （10 mg/L） resulted in an increase of IL-1β mRNA, IL-1β protein, TNF-α mRNA and TNF-α protein, whereas significantly inhibitory effects were observed when cells were incubated with Tat-NBD （WT）. Consisting with p65 expression decrease analyzed by SABC method, NF-KB DNA-binding activity significantly decreased in Tat-NBD （WT） pretreatment group, especially at the largest dose. No significant changes were found in the control peptide group. CONCLUSION： Our result supports that active NF-KB participates in the pathogenesis of STC-induced acute pancreatitis in rats. Tat-NBD （WT） peptide has anti- inflammatory effects in this model and inhibits the inflammation of acinus simulated by LPS.

BDNF pro-peptide：a novel synaptic modulator generated as an N-terminal fragment from the BDNF precursor by proteolytic processing

Most growth factors are initially synthesized as precursors and it was cleaved into bioactive mature domain and pro-domain.However,compared with the expression and function of bioactive mature domain,the biological role of the pro-domain is poorly understood.Unexpectedly,we found that the pro-domain（or pro-peptide）of brain-derived neurotrophic factor（BDNF）,which is well-known neurotrophic factor in brain,has a potential ability to facilitate hippocampal long-term depression.Furthermore,a BDNF polymorphism Val66Met,which substitute valine into methionine at 66 amino acid,impacted the biological activity of the BDNF pro-peptide.We lastly discuss the possible roles of BDNF and its pro-peptide in the generation of neural stem cells and progress of ischemia.

Polydopamine-modified chitin conduits with sustained release of bioactive peptides enhance peripheral nerve regeneration in rats

The introduction of neurotrophic factors into injured peripheral nerve sites is beneficial to peripheral nerve regeneration.However,neurotrophic facto rs are rapidly degraded in vivo and obstruct axonal regeneration when used at a supraphysiological dose,which limits their clinical benefits.Bioactive mimetic peptides have been developed to be used in place of neurotrophic factors because they have a similar mode of action to the original growth fa ctors and can activate the equivalent receptors but have simplified sequences and structures.In this study,we created polydopamine-modified chitin conduits loaded with brain-derived neurotrophic factor mimetic peptides and vascular endothelial growth fa ctor mimetic peptides(Chi/PDA-Ps).We found that the Chi/PDA-Ps conduits were less cytotoxic in vitro than chitin conduits alone and provided sustained release of functional peptides.In this study,we evaluated the biocompatibility of the Chi/P DA-Ps conduits.Brain-derived neurotrophic factor mimetic peptide and vascular endothelial growth fa ctor mimetic peptide synergistically promoted prolife ration of Schwann cells and secretion of neurotrophic factors by Schwann cells and attachment and migration of endothelial cells in vitro.The Chi/P DA-Ps conduits were used to bridge a 2 mm gap between the nerve stumps in rat models of sciatic nerve injury.We found that the application of Chi/PDA-Ps conduits could improve the motor function of rats and reduce gastrocnemius atrophy.The electrophysiological results and the microstructure of regenerative nerves showed that the nerve conduction function and re myelination was further resto red.These findings suggest that the Chi/PDA-Ps conduits have great potential in peripheral nerve injury repair.

Chondrogenesis of Precartilaginous Stem Cells in KLD-12 Self-assembling Peptide Nanofiber Scaffold Loading TGF-β3 Gene

The effect of culture in KLD-12 self-assembling peptide nanofiber scaffold containing TGF-β3 gene on differentiation of precartilaginous stem cells （PSCs） into chondrocytes was studied. KLD-12 was synthesized by solid-state method. After TGF-β3 plasmid was loaded into KLD-12 self-assembling peptide nanofiber scaffold, DNA release ability was investigated. PSCs and hTGF-β3 gene were loaded into KLD-12 3-D scaffold, and MTT assay was performed to investigate the cell proliferation, and ELASA assay was used to investigate the expression of TGF-β3. Specific cartilage matrix was examined by quantitative real-time PCR, immunohistochemistry and Alcian Blue staining. Compared with control group, DNA synthesis level of PSCs reached the peak within 3 days when PSCs were cultured in self-assembling peptide nanofiber scaffold loading TGF-β3 plasmid, and maintained this high level within 2 weeks. MTT results showed that the proliferation ability of experimental group was statistically higher than that in control group （P〈0.05）. Quantitative real-time PCR suggested that the percentage of TGF-β3 positive PSCs in experimental group was higher than that in control group （P〈0.01）. ELISA assay showed that the TGF-β3 protein level increased in supernatant of experimental group＇s PSCs, reached the peak after 72 h and then declined a little to the plateau phase. Compared with the control group, the specific gene of chondrocyte typical extracellular matrix significantly up-regulated （P〈0.01）. The results showed that PSCs differentiated into chondrocytes in self-assembling peptide nanofiber scaffold loading TGF-β3 plasmid, which provided a fresh approach to cartilage tissue engineering.

Effects of Glucagon-Like Peptide 1 on PDX-1, PAX-6 and NKx2.2 Gene Expressions in Isolated Pancreatic Islets

Objective： To observe the effect of glucagon-like peptide 1 （GLP-1） on the gene expressions of transcription factors （PDX-1, PAX-6 and NKx2.2 ） in freshly isolated rat pancreatic islets and investigate the associated physiological and therapeutic implication of GLP-1. Methods： The isolated rat islets were incubated with 10 nmol/L GLP-1 for 1, 3 and 5 days, respectively. Total cellular RNA was extracted and the expressions of PDX-1, PAX-6 and NKx2.2 gene were detected by semiquantity RT-PCR. Results： Compared with the control group, the PDX-1, PAX-6 and NKx2.2 gene expressions were significantly increased after co-cultured with GLP-1 for 1 day （P 〈 0.05）. The effect was shown in a time-dependent manner. All three gene expressions reached the peak on the 5th day. Conclusion： GLP-1 can improve the function of pancreatic islet by regulating the gene expressions of transcription factors in β cells.

Effects of Pyridoxine on Selected Appetite Regulating Peptides mRNA Expression in Hypothalamic PVN/ARC Nuclei and Gastrointestinal Tract Tissues

An experiment was conducted to investigate the effect of dietary pyridoxine on the gene expression of appetite-regulating peptides in the hypothalamus and gastrointestinal tract of rabbits. Thirty-two rabbits were randomly divided into 2 treatments for 8 weeks (16 replicates/group and 1 rabbit/replicate). The treatments were fed a basal diet (control, measured pyridoxine content is 4.51 mg/kg) and the basal diet with a pyridoxine supplementation at 10 mg/kg (pyridoxine, measured pyridoxine content is 14.64 mg/kg). The results showed that dietary pyridoxine did not significantly alter the mRNA levels of neuropeptide Y, agouti related peptide, pro-opiomelanocortin and cocaine, amphetamine regulated transcript, peptide YY and cholecystokinin in arcuate nucleus, peptide YY in jejunum and ileum, and cholecystokinin in duodenum, jejunum and ileum (P > 0.05). Compared with the control, the mRNA levels of corticotropin-releasing hormone and melanocortin 4 receptor in paraventricular nuclei and peptide YY in duodenum were significantly decreased after pyridoxine treatment (P 0.05). In conclusion, the appetite genes of melanocortin 4 receptor and corticotropin-releasing hormone in paraventricular nuclei and peptide YY in duodenum are involved in the pyridoxine-caused hyperphagia.

A comprehensive method to explore inhibitory kinetics and mechanisms of an anticoagulant peptide derived from Crassostrea gigas

A comprehensive method was applied to evaluate the anticoagulant activity of a novel anticoagulant peptide(NAESLRK)derived from oyster(Crassostrea gigas).The anticoagulant peptide drastically reduced the extrinsic clotting activity and also impaired the intrinsic clotting activity slightly.Consistent with clotting data,the thrombin peak height was reduced to 84.7 nmol/L from 123.4 nmol/L,and thrombin generation time was delayed to 4.67 min from 4.42 min when the extrinsic trigger was applied.The inhibitory kinetics of FⅪa,FⅨa,FⅩa,FⅡa,and APC in a purified component system rationally explained the reduction of extrinsic clotting activity and impairment of thrombin generation.Besides the inhibition of FⅩa and FⅡa activity,the activation processes of FⅩand FⅡby intrinsic/extrinsic tenase complex and prothrombinase were also damaged.The anticoagulant activity in the plasma system was the result of comprehensive inhibition of various factors.The research provided a novel method for anticoagulant evaluation and inhibitory mechanism of bioactive peptides from food products.