Spastin and alsin protein interactome analyses begin to reveal key canonical pathways and suggest novel druggable targets

Developing effective and long-term treatment strategies for rare and complex neurodegenerative diseases is challenging. One of the major roadblocks is the extensive heterogeneity among patients. This hinders understanding the underlying disease-causing mechanisms and building solutions that have implications for a broad spectrum of patients. One potential solution is to develop personalized medicine approaches based on strategies that target the most prevalent cellular events that are perturbed in patients. Especially in patients with a known genetic mutation, it may be possible to understand how these mutations contribute to problems that lead to neurodegeneration. Protein–protein interaction analyses offer great advantages for revealing how proteins interact, which cellular events are primarily involved in these interactions, and how they become affected when key genes are mutated in patients. This line of investigation also suggests novel druggable targets for patients with different mutations. Here, we focus on alsin and spastin, two proteins that are identified as “causative” for amyotrophic lateral sclerosis and hereditary spastic paraplegia, respectively, when mutated. Our review analyzes the protein interactome for alsin and spastin, the canonical pathways that are primarily important for each protein domain, as well as compounds that are either Food and Drug Administration–approved or are in active clinical trials concerning the affected cellular pathways. This line of research begins to pave the way for personalized medicine approaches that are desperately needed for rare neurodegenerative diseases that are complex and heterogeneous.

A practical synthesis of trifluorophenyl R-amino acid:The key precursor for the new anti-diabetic drug sitagliptin

Sitagliptin is the first new anti-diabetic drug in DPP-Ⅳ inhibitor class. The general synthesis of sitagliptin is by coupling of the β-amino acid fragment with the heterocycle fragment. Though the specific β-amino acid can be easily made from the corresponding R-amino acid by Arndt-Eistert hornologation, the optically pure precursor R-amino acid is difficult to prepare. We herein reported a practical protocol to make the trifluorophenyl substituted R-amino acid 4 in 〉99.9% ee and 40.3% yield by the enzymatic resolution employing enantioselective hydrolysis and a general separation procedure. This protocol requires only cheap starting materials and friendly reaction condition. The procedure not only allows people to prepare the drug substance, but also provides an alternative method for prepareing the rare α-amino acid and the subsequent β-amino acid.

The interaction between the Wnt/β-catenin signaling cascade and PKG activation in cancer

The activation of the Wnt/β-catenin signaling cascade has been well studied and documented in colorectal cancer（CRC）.The long-term use of non-steroidal anti-inflammatory drugs（NSAIDs） has been shown to reduce the incidence and risk of death from CRC in numerous epidemiological studies.The NSA1 D sulindac has also been reported to cause regression of precancerous adenomas in individuals with familial adenomatous polyposis who are at high risk of developing CRC.The mechanism responsible for cancer chemopreventive activity of NSAIDs is not well understood but may be unrelated to their cyclooxygenase inhibitory activity.Emerging evidence suggests that sulindac inhibits the growth of colon tumor cells by suppressing the activity of certain phosphodiesterase isozymes to activate cGMβ-dependent protein kinase,PKG,through the elevation of the second messenger cyclic guanosine monophosphote,cGMP.PKG activation has been shown to inhibit the nuclear translocation of β-catenin,reduce β-catenin mRNA and protein levels,and suppress the transcriptional activity of β-catenin.This review describes the relationship between the Wnt/β-catenin signaling cascade and the activation of PKG through PDE inhibition and elevation of intracellular cGMP levels.

New insights into renal lipid dysmetabolism in diabetic kidney disease

Lipid dysmetabolism is one of the main features of diabetes mellitus and manifests by dyslipidemia as well as the ectopic accumulation of lipids in various tissues and organs,including the kidney.Research suggests that impaired cholesterol metabolism,increased lipid uptake or synthesis,increased fatty acid oxidation,lipid droplet accumulation and an imbalance in biologically active sphingolipids(such as ceramide,ceramide-1-phosphate and sphingosine-1-phosphate)contribute to the development of diabetic kidney disease(DKD).Currently,the literature suggests that both quality and quantity of lipids are associated with DKD and contribute to increased reactive oxygen species production,oxidative stress,inflammation,or cell death.Therefore,control of renal lipid dysmetabolism is a very important therapeutic goal,which needs to be archived.This article will review some of the recent advances leading to a better understanding of the mechanisms of dyslipidemia and the role of particular lipids and sphingolipids in DKD.

Inhibition of cerebral ischemia/reperfusion injuryinduced apoptosis:nicotiflorin and JAK2/STAT3 pathway

Nicotiflorin is a flavonoid extracted from Carthamus tinctorius.Previous studies have shown its cerebral protective effect,but the mechanism is undefined.In this study,we aimed to determine whether nicotiflorin protects against cerebral ischemia/reperfusion injury-induced apoptosis through the JAK2/STAT3 pathway.The cerebral ischemia/reperfusion injury model was established by middle cerebral artery occlusion/reperfusion.Nicotiflorin（10 mg/kg） was administered by tail vein injection.Cell apoptosis in the ischemic cerebral cortex was examined by hematoxylin-eosin staining and terminal deoxynucleotidyl transferase d UTP nick end labeling assay.Bcl-2 and Bax expression levels in ischemic cerebral cortex were examined by immunohistochemial staining.Additionally,p-JAK2,p-STAT3,Bcl-2,Bax,and caspase-3 levels in ischemic cerebral cortex were examined by western blot assay.Nicotiflorin altered the shape and structure of injured neurons,decreased the number of apoptotic cells,down-regulates expression of p-JAK2,p-STAT3,caspase-3,and Bax,decreased Bax immunoredactivity,and increased Bcl-2 protein expression and immunoreactivity.These results suggest that nicotiflorin protects against cerebral ischemia/reperfusion injury-induced apoptosis via the JAK2/STAT3 pathway.

Glioblastoma multiforme:Diagnosis, treatment, and invasion

Glioblastoma multiforme(GBM) is an essentially incurable brain tumor, which has been explored for approximately a century. Nowadays, surgical resection, chemotherapy, and radiation therapy are still the standardized therapeutic options. However, due to the intrinsic invasion and metastasis features and the resistance to chemotherapy, the survival rate of glioblastoma patients remains unsatisfactory. To improve the current situation, much more research is needed to provide comprehensive knowledge of GBM. In this review, we summarize the latest updates on GBM treatment and invasion. Firstly, we review the traditional and emerging therapies that have been used for GBM treatment. Given the limited efficiency of these therapies, we further discuss the role of invasion in GBM recurrence and progression, and present current research progress on the mode and mechanisms of GBM invasion.

RNA Extraction from Herba Violae Roots with Low-temperature Sectioning Method

[ Objective ] This study aimed to investigate the optimal method for extracting RNA from roots of medicinal plant herba violae by comparing the effects of liquid nitrogen grinding method and low-temperature sectioning method on RNA extraction. [ Method] Roots of herba violae were respectively crushed by using liquid nitrogen grinding method and low-temperature sectioning method to extract RNA. The extraction effects of these two methods were compared based on detec- tion of RNA concentration, purity and integrity and amplification of GAPDH gene by RT-PCR. [Result] The concentration of RNA extracted by liquid nitrogen grinding method and low-temperature sectioning method was 1.21 and 3.57 p^g/~, respectively. Both RNA extracted by these two methods showed two distinct bands after agarose gel electrophoresis. The ratio of brightness of the 28S rRNA to the 18S rRNA bands was greater than 1. PCR amplification showed that the length of GAPDH gene was about 230 bp, which was consistent with the expected result. [ Conclusion ] The experimental results indicated that using low-tempera ture sectioning method to crush the roots of herba violae can meet the needs of most molecular biological experiments including gene cloning and expression analysis, which is an effective and simple method for extracting RNA from plant roots.

Sulindac sulfide selectively increases sensitivity of ABCC1 expressing tumor cells to doxorubicin and glutathione depletion

ATP-binding cassette（ABC） transporters ABCC1（MRP1）,ABCB1（P-gp）,and ABCG2（BCRP） contribute to chemotherapy failure.The primary goals of this study were to characterize the efficacy and mechanism of the nonsteroidal anti-inflammatory drug（NSAID）,sulindac sulfide,to reverse ABCC1 mediated resistance to chemotherapeutic drugs and to determine if sulindac sulfide can influence sensitivity to chemotherapeutic drugs independently of drug efflux.Cytotoxicity assays were performed to measure resistance of ABC-expressing cell lines to doxorubicin and other chemotherapeutic drugs.NSAIDs were tested for the ability to restore sensitivity to resistance selected tumor cell lines,as well as a large panel of standard tumor cell lines.Other experiments characterized the mechanism by which sulindac sulfide inhibits ABCC1 substrate and co-substrate（GSH） transport in isolated membrane vesicles and intact cells.Selective reversal of multi-drug resistance（MDR）,decreased efflux of doxorubicin,and fluorescent substrates were demonstrated by sulindac sulfide and a related NSAID,indomethacin,in resistance selected and engineered cell lines expressing ABCC 1,but not ABCB 1 or ABCG2.Sulindac sulfide also inhibited transport of leukotriene C_4 into membrane vesicles.Sulindac sulfide enhanced the sensitivity to doxorubicin in 24 of 47 tumor cell lines,including all melanoma lines tested（7-7）.Sulindac sulfide also decreased intracellular GSH in ABCC1 expressing cells,while the glutathione synthesis inhibitor,BSO,selectively increased sensitivity to sulindac sulfide induced cytotoxicity.Sulindac sulfide potently and selectively reverses ABCC1-mediated MDR at clinically achievable concentrations.ABCC1 expressing tumors may be highly sensitive to the direct cytotoxicity of sulindac sulfide,and in combination with chemotherapeutic drugs that induce oxidative stress.

Identification and functional analysis of miRNAs in developing kernels of a viviparous mutant in maize

Given the important roles of miRNAs in post-transcriptional gene regulation, identification of differentially expressed miRNAs will facilitate the elucidation of molecular mechanisms underlying kernel development. In this study, we constructed a small RNA library to comprehensively represent the full complement of individual small RNAs and to characterize miRNA expression profiles in pooled ears of maize(Zea mays L.) at 10, 15,20, 22, 25 and 30 days after pollination(DAP). At least 21 miRNAs were differentially expressed. The differential expression of three of these miRNAs, i.e., miR528a, miR167a and miR160b, at each stage was verified by qRT-PCR. The results indicated that these miRNAs might be involved in kernel development. In addition, the predicted functions of target genes indicated that most of the target genes are involved in signal transduction and cell communication pathways, particularly the auxin signaling pathway. The expression of candidate germination-associated miRNAs was analyzed by hybridization to a maize genome microarray, and revealed differential expression of genes involved in plant hormone signaling pathways. This finding suggests that phytohormones play a critical role in the development of maize kernels. We found that in combination with other miRNAs, miR528a regulated a putative laccase, a Ring-H2 zinc finger protein and a MADS box-like protein, whereas miR167a and miR160b regulated multiple target genes,including ARF(auxin response factor), a member of the B3 transcription factor family. All three miRNAs are important for ear germination, development and physiology. The small RNA transcriptomes and mRNA obtained in this study will help us gain a betterunderstanding of the expression and function of small RNAs in the development of maize kernel.

Targeting plasminogen activator inhibitor-1 to prevent vascular disease

Plasminogen activator inhibitor-1(PAI-1)is the primary inhibitor of urinary-type and tissue-type plasmino-gen activators and a key regulator of fibrinolysis.PAI-1 also regulates the function of vascular cells,includingvascular smooth muscle cells(VSMCs).

Role of PAI-1 in adipose tissue senescence and inflammation in obesity

Plasminogen activator inhibitor-1(PAI-1)is a member of the evolutionarily conserved serine pro⁃tease inhibitor family.The increased expression of PAI-1 leads to pathological diseases such as vascular diseases,obesity,and metabolic syndrome.Senescence-associated secretory phenotype(SASP)mediates tissue damage and plays a role in adipose tissue dysfunction.Chronic inflammation in adipose tissue is associated with the development of metabolic diseases,including obesity,insulin resistance,and type 2 diabetes.PAI-1 plays a vital role in adipose tissue physiology,glucose metabolism,insulin secretion and sensitivity,inflammation,and macrophage chemotaxis.This article reviews the possible role of PAI-1,as one of the SASP markers,and speculates the potential role of PAI-1 in adipose tissue senescence and inflammatory macrophage infiltration in obesity.

Small molecule conjugates with selective estrogen receptor β agonism promote anti-aging benefits in metabolism and skin recovery

Estrogen is imperative to mammalian reproductivity,metabolism,and aging.However,the hormone activating estrogen receptor(ERs)αcan cause major safety concerns due to the enrichment of ERαin female tissues and certain malignancies.In contrast,ERβis more broadly expressed in metabolic tissues and the skin.Thus,it is desirable to generate selective ERβagonist conjugates for maximizing the therapeutic effects of ERs while minimizing the risks of ERαactivation.Here,we report the design and production of small molecule conjugates containing selective non-steroid ERβagonists Gtx878 or genistein.Treatment of aged mice with our synthesized conjugates improved aging-associated declines in insulin sensitivity,visceral adipose integrity,skeletal muscle function,and skin health,with validation in vitro.We further uncovered the benefits of ERβconjugates in the skin using two inducible skin injury mouse models,showing increased skin basal cell proliferation,epidermal thickness,and wound healing.Therefore,our ERβ-selective agonist conjugates offer novel therapeutic potential to improve aging-associated conditions and aid in rejuvenating skin health.

Glucose-mediated mitochondrial reprogramming by cholesterol export at TM4SF5-enriched mitochondria-lysosome contact sites

Background:Transmembrane 4 L six family member 5(TM4SF5)translocates subcellularly and functions metabolically,although it is unclear how intracellu-lar TM4SF5 translocation is linked to metabolic contexts.It is thus of interests to understand how the traffic dynamics of TM4SF5 to subcellular endosomal membranes are correlated to regulatory roles of metabolisms.Methods:Here,we explored the metabolic significance of TM4SF5 localization at mitochondria-lysosome contact sites(MLCSs),using in vitro cells and in vivo animal systems,via approaches by immunofluorescence,proximity labelling based proteomics analysis,organelle reconstitution etc.Results:Upon extracellular glucose repletion following depletion,TM4SF5 became enriched at MLCSs via an interaction between mitochondrial FK506-binding protein 8(FKBP8)and lysosomal TM4SF5.Proximity labeling showed molecular clustering of phospho-dynamic-related protein I(DRP1)and certain mitophagy receptors at TM4SF5-enriched MLCSs,leading to mitochondrial fis-sion and autophagy.TM4SF5 bound NPC intracellular cholesterol transporter 1(NPC1)and free cholesterol,and mediated export of lysosomal cholesterol to mitochondria,leading to impaired oxidative phosphorylation but intact tri-carboxylic acid(TCA)cycle andβ-oxidation.In mouse models,hepatocyte Tm4sf5 promoted mitophagy and cholesterol transport to mitochondria,both with positive relations to liver malignancy.Conclusions:Our findings suggested that TM4SF5-enriched MLCSs regu-late glucose catabolism by facilitating cholesterol export for mitochondrial reprogramming,presumably while hepatocellular carcinogenesis,recapitulating aspects for hepatocellular carcinoma metabolism with mitochondrial repro-gramming to support biomolecule synthesis in addition to glycolytic energetics.

JW-1-283 inhibits melanoma tumor growth via stabilization of the p53 pathway

Melanoma is a lethal skin malignancy and the fifth most diagnosed cancer in the United States.1 Currently,for unresectable melanoma,the recommended treatment options include checkpoint inhibitor immunotherapy targeting programmed cell death 1(PD-1),and inhibitors targeting the mitogen-activated protein kinase(MAPK)pathway.However,the response rate may vary among the patients,and therefore demanding the development of novel treatment strategies.Tumor suppressor TP53has been suggested as one of the critical regulators mediating the aggressiveness and progression of melanoma.

Bioactive materials from berberine-treated human bone marrow mesenchymal stem cells promote alveolar bone regeneration by regulating macrophage polarization

Alveolar bone regeneration has been strongly linked to macrophage polarization.M1 macrophages aggravate alveolar bone loss,whereas M2 macrophages reverse this process.Berberine(BBR),a natural alkaloid isolated and refined from Chinese medicinal plants,has shown therapeutic effects in treating metabolic disorders.In this study,we first discovered that culture supernatant(CS)collected from BBR-treated human bone marrow mesenchymal stem cells(HBMSCs)ameliorated periodontal alveolar bone loss.CS from the BBR-treated HBMSCs contained bioactive materials that suppressed the M1 polarization and induced the M2 polarization of macrophages in vivo and in vitro.To clarify the underlying mechanism,the bioactive materials were applied to different animal models.We discovered macrophage colony-stimulating factor(M-CSF),which regulates macrophage polarization and promotes bone formation,a key macromolecule in the CS.Injection of pure M-CSF attenuated experimental periodontal alveolar bone loss in rats.Colony-stimulating factor 1 receptor(CSF1R)inhibitor or anti-human M-CSF(M-CSF neutralizing antibody,Nab)abolished the therapeutic effects of the CS of BBR-treated HBMSCs.Moreover,AKT phosphorylation in macrophages was activated by the CS,and the AKT activator reversed the negative effect of the CSF1R inhibitor or Nab.These results suggest that the CS of BBR-treated HBMSCs modulates macrophage polarization via the M-CSF/AKT axis.Further studies also showed that CS of BBR-treated HBMSCs accelerated bone formation and M2 polarization in rat teeth extraction sockets.Overall,our findings established an essential role of BBR-treated HBMSCs CS and this might be the first report to show that the products of BBR-treated HBMSCs have active effects on alveolar bone regeneration.

A structural view of the antibiotic degradation enzyme NDM-1 from a superbug

Gram-negative Enterobacteriaceae with resistance to carbapenem conferred by New Delhi metallo-β-lactamase 1(NDM-1)are a type of newly discovered antibioticresistant bacteria.The rapid pandemic spread of NDM-1 bacteria worldwide(spreading to India,Pakistan,Europe,America,and Chinese Taiwan)in less than 2 months characterizes these microbes as a potentially major global health problem.The drug resistance of NDM-1 bacteria is largely due to plasmids containing the blaNDM-1 gene shuttling through bacterial populations.The NDM-1 enzyme encoded by the blaNDM-1 gene hydrolyzes β-lactam antibiotics,allowing the bacteria to escape the action of antibiotics.Although the biological functions and structural features of NDM-1 have been proposed according to results from functional and structural investigation of its homologues,the precise molecular characteristics and mechanism of action of NDM-1 have not been clarified.Here,we report the threedimensional structure of NDM-1 with two catalytic zinc ions in its active site.Biological and mass spectroscopy results revealed that D-captopril can effectively inhibit the enzymatic activity of NDM-1 by binding to its active site with high binding affinity.The unique features concerning the primary sequence and structural conformation of the active site distinguish NDM-1 from other reported metallo-β-lactamases(MBLs)and implicate its role in wide spectrum drug resistance.We also discuss the molecular mechanism of NDM-1 action and its essential role in the pandemic of drug-resistant NDM-1 bacteria.Our results will provide helpful information for future drug discovery targeting drug resistance caused by NDM-1 and related metallo-β-lactamases.

Metformin and metabolic diseases： a focus on hepatic aspects

Metformin has been widely used as a diabetes （T2D）. As a drug that primarily targets first-line anti-diabetic medicine for the treatment ot type Z the liver, metformin suppresses hepatic glucose production （HGP）, serving as the main mechanism by which metformin improves hyperglycemia of T2D. BiochemicaUy, metformin suppresses gluconeogenesis and stimulates glycolysis. Metformin also inhibits glycogenolysis, which is a pathway that critically contributes to elevated HGP. While generating beneficial effects on hyperglycemia, metformin also improves insulin resistance and corrects dyslipidemia in patients with T2D. These beneficial effects of metformin implicate a role for metformin in managing non-alcoholic fatty liver disease. As supported by the results from both human and animal studies, metformin improves hepatic steatosis and suppresses liver inflammation. Mechanistically, the beneficial effects of metformin on hepatic aspects are mediated through both adenosine monophosphate-activated protein kinase （AMPK）-dependent and AMPK-independent pathways. In addition, metformin is generally safe and may also benefit patients with other chronic liver diseases.

The newly emerged SARS-Like coronavirus HCoV-EMC also has an “Achilles’ heel”: current effective inhibitor targeting a 3C-like protease

From the global outbreak of SARS-CoV caused infection disease in 2003,coronaviruses(CoVs)are known to be a great threat to the human health.Recently,a new SARS-like coronavirus,human betacoronavirus 2c EMC/2012(HCoV-EMC),has been identified and the appearance of this new CoV raises concerns that a new spread of CoV may occurs in the future.By solving the crystal structure of HCoV-EMC main protease with a wide-spectrum anti-CoV inhibitor N3,we confi rmed that that N3 blocks the function of HCoV-EMC main protease through a similar mechanism to other CoVs.Together with the good pharmaceutical features,N3 is conceivable to be effective to HCoV-EMC and other CoVs appearing in the future.These fi ndings make it convincing that CoVs will not be a threat to human health.

The nucleoprotein of severe fever with thrombocytopenia syndrome virus processes a stable hexameric ring to facilitate RNA encapsidation

Severe fever with thrombocytopenia syndrome virus(SFTSV),a member of the Phlebovirus genus from the Bunyaviridae family endemic to China,is the causative agent of life-threatening severe fever with thrombocyto-penia syndrome(SFTS),which features high fever and hemorrhage.Similar to other negative-sense RNA viruses,SFTSV encodes a nucleocapsid protein(NP)that is essen-tial for viral replication.NP facilitates viral RNA encapsida-tion and is responsible for the formation of ribonucleopro-tein complex.However,recent studies have indicated that NP from Phlebovirus members behaves in inhomogene-ous oligomerization states.In the present study,we report the crystal structure of SFTSV NP at 2.8Åresolution and demonstrate the mechanism by which it processes a ring-shaped hexameric form to accomplish RNA encapsida-tion.Key residues essential for oligomerization are identi-fi ed through mutational analysis and identifi ed to have a signifi cant impact on RNA binding,which suggests that correct formation of highly ordered oligomers is a criti-cal step in RNA encapsidation.The fi ndings of this work provide new insights into the discovery of new antiviral reagents for Phlebovirus infection.

A versatile building block:the structures and functions of negative-sense single-stranded RNA virus nucleocapsid proteins

Nucleocapsid protein(NPs)of negative-sense single-stranded RNA(-ssRNA)viruses function in different stages of viral replication,transcription,and maturation.Structural investigations show that-ssRNA viruses that encode NPs preliminarily serve as structural building blocks that encapsidate and protect the viral genomic RNA and mediate the interaction between genomic RNA and RNA-dependent RNA polymerase.However,recent structural results have revealed other bio-logical functions of-ssRNA viruses that extend our understanding of the versatile roles of virally encoded NPs.