Proteases are essential for homeostasis,and their primary function is proteolytic in extracellular and intracellular compartments.The deregulation of expression,abundance,and activity of proteases has been related to ...Proteases are essential for homeostasis,and their primary function is proteolytic in extracellular and intracellular compartments.The deregulation of expression,abundance,and activity of proteases has been related to several pathologies,including cancer.This deregulation contributes to their pro-tumorigenic activity since they participate in the degradation of extracellular matrix components and adhesion molecules,and the activation of growth factors.However,some proteases,such as ADAM metallopeptidase with thrombospondin type 1 motif 8 and kallikrein-related peptidases 5 and 10,have emerged as tumor suppressors due to their antitumoral actions in specific cancer contexts.In this article,we discuss the antitumoral effects of ADAM metallopeptidase with thrombospondin type 1 motif 8,kallikrein-related peptidases 5 and 10 that have been described to date,suggesting their potential use as novel biomarkers and therapeutic targets in cancer.展开更多
BACKGROUND Colorectal cancer(CRC)is the third most frequent and the second most fatal cancer.The search for more effective drugs to treat this disease is ongoing.A better understanding of the mechanisms of CRC develop...BACKGROUND Colorectal cancer(CRC)is the third most frequent and the second most fatal cancer.The search for more effective drugs to treat this disease is ongoing.A better understanding of the mechanisms of CRC development and progression may reveal new therapeutic strategies.Ubiquitin-specific peptidases(USPs),the largest group of the deubiquitinase protein family,have long been implicated in various cancers.There have been numerous studies on the role of USPs in CRC;however,a comprehensive view of this role is lacking.AIM To provide a systematic review of the studies investigating the roles and functions of USPs in CRC.METHODS We systematically queried the MEDLINE(via PubMed),Scopus,and Web of Science databases.RESULTS Our study highlights the pivotal role of various USPs in several processes implicated in CRC:Regulation of the cell cycle,apoptosis,cancer stemness,epithelial–mesenchymal transition,metastasis,DNA repair,and drug resistance.The findings of this study suggest that USPs have great potential as drug targets and noninvasive biomarkers in CRC.The dysregulation of USPs in CRC contributes to drug resistance through multiple mechanisms.CONCLUSION Targeting specific USPs involved in drug resistance pathways could provide a novel therapeutic strategy for overcoming resistance to current treatment regimens in CRC.展开更多
In this present work, the best conditions for production of peptidases under solid state fermentation by the fungi Penicillium corylophilum and Penicillium waksmanii, partial purification using Sephadex G-75 gel filtr...In this present work, the best conditions for production of peptidases under solid state fermentation by the fungi Penicillium corylophilum and Penicillium waksmanii, partial purification using Sephadex G-75 gel filtration column, as well as the biochemical characterization of the partial purified enzymes were investigated. P. corylophilum showed the best production in medium containing wheat bran, agro-industrial residue, without additives （egg albumin or casein）, in which peptidase activity reached 520 U mL^-1 and the enzyme displayed the optimum activity between pH range from 7 to 8 and 60 ℃. It also showed high stability in wide pH range and temperature until 45 ℃ for 60 min of incubation. On the other hand, P. waksmanii, the best production was noted in a medium containing wheat bran （95%） and casein （5%）, reaching 545 U mL^-1, with proteolytic optimum activity at pH 7.5 and 55 ℃. The enzyme was mainly stable in pH range from 8 to 9 and at temperatures until 45 ℃ for 60 rain of incubation. The peptidases secreted by both fungi were inhibited in the presence of phenylmethane sulfonyl fluoride, showing that they belong to the subclass of serine peptidases.展开更多
While exerting their metabolic activities in the gastrointestinal milieu,probiotics impact the host well-being by boosting immunity,treating metabolic disorders,and modulating microbiota and metabolome.Due to the high...While exerting their metabolic activities in the gastrointestinal milieu,probiotics impact the host well-being by boosting immunity,treating metabolic disorders,and modulating microbiota and metabolome.Due to the high incidence of gluten-based disorders,the present work aims to deeply explore the metabolism of two selected microbial consortia(MCs)during gluten digestion under simulated gastrointestinal conditions.Featured by high protease and peptidase activity,both MCs accounted for different lactic acid bacteria and Bacillus strains that were combined with two commercial protease enzymes.Gluten substrates were used as purified extracts,white and whole wheat breads.Control samples,instead,relied onto the microbial enzyme lack.Twenty-four hours of simulated digestion were sufficient to completely hydrolyze gluten in one of the two MC-containing experimental sets,and the relative 48 h-digested extract did not alter the cytokine expression in duodenal biopsies from celiac disease(CeD)patients.When digested samples were assayed for antioxidant and phytase activities,microbial enzymes demonstrated to significantly improve both 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)and 1,1-diphenyl-2-picrylhydrazyl(DPPH)scavenging activity and to decrease the phytic acid concentration.The inspection of the free amino acid profiles allowed for distinguishing the two MCs,whereas the detection of a heterogeneous panel of volatile organic compounds supported the presence/activity of microbial enzymes without statistically significant differences between MCs.As functional contribution,digested extracts with MCs also proved to reduce the inflammatory cytokine concentrations in cell lines exposed to lipopolysaccharide trigger.Therefore,in line with studies exploring novel adjuvant therapies,the present innovative probiotic consortium featured by high gluten-hydrolyzing metabolism also showed the capability to improve various parameters usually found to be altered in patients affected by gluten-based disorders or CeD.展开更多
Background: Tumor angiogenesis is related to solid tumor occurrence. Ubiquitin-specific peptidase 13 (USP13) is a deubiquitinating enzyme with a pivotal effect on tumor proliferation, metastasis, and tumorigenesis. No...Background: Tumor angiogenesis is related to solid tumor occurrence. Ubiquitin-specific peptidase 13 (USP13) is a deubiquitinating enzyme with a pivotal effect on tumor proliferation, metastasis, and tumorigenesis. Nonetheless, its effect on colorectal cancer (CRC) angiogenesis remains poorly understood. Methods: Human umbilical vein endothelial cells (HUVECs) and CRC cells were cultivated, followed by USP13 knockdown/overexpression using shRNA lentiviral vectors or plasmids. Conditioned media (CM) from treated CRC cells were collected to assess HUVEC migration, invasion, and tube formation. Phosphatase and tensin homolog (PTEN) overexpression and recombinant vascular endothelial growth factor A (VEGFA) rescue experiments were performed. Molecular mechanisms were analyzed via Western blot (PTEN, p-AKT, VEGFA), co-immunoprecipitation (PTEN ubiquitination), and in vivo nude mice study to detect the role of USP13 in tumor angiogenesis. Results: USP13 expression in CRC cells is downregulated and negatively related to platelet endothelial cell adhesion molecule-1 (CD31) expression. Furthermore, the conditioned medium from CRC cells with USP13 knockdown significantly promoted HUVEC migration, invasion, and tube formation, while USP13 overexpression exerted the opposite effect. Additionally, USP13 overexpression significantly increased PTEN expression while decreasing protein kinase B (AKT) phosphorylation levels. Concurrently, USP13 overexpression significantly reduced PTEN ubiquitination, whereas USP13 knockdown remarkably increased this modification. Overexpression of PTEN in sh-USP13 CRC cells decreased the expression levels of VEGFA and p-AKT. USP13 also inhibited tumor angiogenesis through downregulating VEGFA, and recombinant VEGFA blocked the inhibition of the conditioned medium from USP13-overexpressing CRC cells against HUVEC angiogenesis in vivo. Conclusions: USP13 downregulated VEGFA and inhibited tumor angiogenesis via the PTEN-AKT pathway.展开更多
This letter comments on the recently published manuscript by Yu et al,in which the authors revealed a novel mechanism by which the m6A-modified long noncoding RNA kinesin family member 9-antisense RNA 1 promotes stemn...This letter comments on the recently published manuscript by Yu et al,in which the authors revealed a novel mechanism by which the m6A-modified long noncoding RNA kinesin family member 9-antisense RNA 1 promotes stemness and sorafenib resistance of hepatocellular carcinoma(HCC)through ubiquitinspecific peptidase 1-mediated deubiquitination of oncogene short stature homeobox 2.Given the high mortality rate and poor prognosis of HCC,the findings by Yu et al open a new avenue for overcoming HCC burden by focusing on kinesin family member 9-antisense RNA 1 and short stature homeobox 2 as prognostic markers and therapeutic targets.展开更多
Background:Alterations in the expression of human kallikrein-related peptidases(KLKs)have been described in patients with Alzheimer’s disease(AD).We elucidated the suitability of KLK6,KLK8 and KLK10 to distinguish AD...Background:Alterations in the expression of human kallikrein-related peptidases(KLKs)have been described in patients with Alzheimer’s disease(AD).We elucidated the suitability of KLK6,KLK8 and KLK10 to distinguish AD from NC and explored associations with established AD biomarkers.Methods:KLK levels in cerebrospinal fluid(CSF),as determined by ELISA,were compared between 32 AD patients stratified to A/T/(N)system with evidence for amyloid pathology and of 23 normal controls with normal AD biomarkers.Associations between KLK levels and clinical severity,CSF and positron emission tomography(PET)based AD biomarkers were tested for.Results:Levels of KLK6 and KLK10 were significantly increased in AD.KLK6 differed significantly between AD A+/T+/N+and AD A+/T−/N+or NC with an AUC of 0.922.CSF pTau and tTau levels were significantly associated with KLK6 in AD.Conclusions:KLK6 deserves further investigations as a potential biomarker of Tau pathology in AD.展开更多
Peptidases are essential for intracellular protein processing,signaling and homeostasis,physiological processes and for digestion of food.Moreover,peptidases are important biotechnological enzymes used in processes su...Peptidases are essential for intracellular protein processing,signaling and homeostasis,physiological processes and for digestion of food.Moreover,peptidases are important biotechnological enzymes used in processes such as industrial food processing,leather manufacturing and the washing industry.Identification of peptidases is a crucial step in their characterization but peptidase annotation is not a trivial task due to their large sequence diversity.In the present study short,conserved sequence profiles were generated for all peptidase families with more than four members in the comprehensive Merops peptidase database.The sequence profiles were combined with the Homology to Peptide Pattern(Hotpep)method for automatic annotation of peptidases.This method is a standalone software that annotates protease sequences to Merops family and subgroup and is suitable for large-scale sequence analysis.Compared to the Mammalian Degradome Database Hotpep-protease had an accuracy of 92%and a sensitivity of 96%for annotation of the human degradome.Annotation by commonly used methods(Blast and conserved domains)had an accuracy of 69%and a sensitivity of 78%.For fungal genomes,there were large differences between annotation with Hotpep-protease,Blast-and Hidden Markov Model-based annotation and the Merops annotation,which confirms the difficulty of large-scale peptidase annotation.Manual annotation indicated that Hotpep-protease had a positive prediction rate of 0.90 compared to a positive prediction rate of 0.67 for Blast search.Hence,Hotpep-protease is highly accurate method for fast and accurate annotation of peptidases.展开更多
The management of colorectal cancer(CRC)poses a significant challenge,necessitating the development of innovative and effective therapeutics.Our research has shown that notoginsenoside Ft1(Ng-Ft1),a small molecule,mar...The management of colorectal cancer(CRC)poses a significant challenge,necessitating the development of innovative and effective therapeutics.Our research has shown that notoginsenoside Ft1(Ng-Ft1),a small molecule,markedly inhibits subcutaneous tumor formation in CRC and enhances the proportion of CD8^(+)T cells in tumor-bearing mice,thus restraining tumor growth.Investigation into the mechanism revealed that Ng-Ft1 selectively targets the deubiquitination enzyme USP9X,undermining its role in shieldingβ-catenin.This leads to a reduction in the expression of downstream effectors in the Wnt signaling pathway.These findings indicate that Ng-Ft1 could be a promising small-molecule treatment for CRC,working by blocking tumor progression via the Wnt signaling pathway and augmenting CD8^(+)T cell prevalence within the tumor environment.展开更多
BACKGROUND Serpin peptidase inhibitor clade H member 1(SERPINH1)was initially recognized as an oncogene implicated in various human malignancies.Nevertheless,the clinical relevance and functional implications of SERPI...BACKGROUND Serpin peptidase inhibitor clade H member 1(SERPINH1)was initially recognized as an oncogene implicated in various human malignancies.Nevertheless,the clinical relevance and functional implications of SERPINH1 in colorectal cancer(CRC)remain largely elusive.AIM To investigate the effects of SERPINH1 on CRC cells and its specific mechanism.METHODS Quantitative real-time polymerase chain reaction,western blotting analysis,The Cancer Genome Atlas data mining and immunohistochemistry were employed to examine SERPINH1 expression in CRC cell lines and tissues.A series of in-vitro assays were performed to demonstrate the function of SERPINH1 and its possible mechanisms in CRC.RESULTS SERPINH1 demonstrated elevated expression levels in both CRC cells and tissues,manifested at both mRNA and protein tiers.Elevated SERPINH1 levels correlated closely with advanced T stage,lymph node involvement,and distant metastasis,exhibiting a significant association with poorer overall survival among CRC patients.Subsequent investigations unveiled that SERPINH1 overexpression notably bolstered CRC cell proliferation,invasion,and migration in vitro,while conversely,SERPINH1 knockdown elicited the opposite effects.Gene set enrichment analysis underscored a correlation between SERPINH1 upregulation and genes associated with cell cycle regulation.Our findings underscored the capacity of heightened SERPINH1 levels to expedite G1/S phase cell cycle progression via phosphatidylinositol 3-kinase/AKT/mechanistic target of rapamycin pathway activation,thereby facilitating CRC cell invasion and migration.CONCLUSION These findings imply a crucial involvement of SERPINH1 in the advancement and escalation of CRC,potentially positioning it as a novel candidate for prognostic assessment and therapeutic intervention in CRC management.展开更多
AIM: Cysteine peptidase (CP) and its inhibitor (CPI) are a matrix protease that may be associated with colorectal carcinoma invasion and progression, and vitamin E is also a stimulator of the immunological system. Our...AIM: Cysteine peptidase (CP) and its inhibitor (CPI) are a matrix protease that may be associated with colorectal carcinoma invasion and progression, and vitamin E is also a stimulator of the immunological system. Our purpose was to determine the correlation between the expression of cysteine peptidases and their endogenous inhibitors,and the level of vitamin E in sera of patients with colorectal cancer in comparison with healthy individuals.METHODS: The levels of cysteine peptidases and their inhibitors were determined in the sera of patients with primary and metastatic colorectal carcinoma and healthy individuals using fluorogenic substrate, and the level of vitamin E was determined by HPLC.RESULTS: The levels of cysteine peptidases and their inhibitors were significantly higher in the metastatic colorectal cancer patients than that in the healthy controls (P＜0.05).The activity of CP increased 2.2-fold, CPI 2.8-fold and vitamin E decreased 3.4-fold in sera of patients with metastasis in comparison with controls. The level of vitamin E in healthy individuals was higher, whereas the activity of cysteine peptidases and their inhibitors associated with complexes was lower than that in patients with cancer of the digestive tract.CONCLUSION: These results suggest that the serum levels of CP and their inhibitors could be an indicator of the prognosis for patients with metastatic colorectal cancer. Vitamin E can be administered prophylactically to prevent digestive tract neoplasmas.展开更多
Kallikrein-related peptidases (KLKs) have been proposed as potential cancer biomarkers. Kallikrein-related peptidase 5 (KLK5) is a secreted trypsin-like protease of the KLKs. Until now, detection of KLK5 in both biolo...Kallikrein-related peptidases (KLKs) have been proposed as potential cancer biomarkers. Kallikrein-related peptidase 5 (KLK5) is a secreted trypsin-like protease of the KLKs. Until now, detection of KLK5 in both biological fluids and tissues has been described frequently due to the potential of being a new cancer biomarker. Our objective was to prepare KLK5 antibodies and establish an ELISA method for KLK5 to study the possible clinical application of KLK5 as a biomarker for malignancies. In this study, recombinant KLK5 protein was produced and purified using a prokaryotic expression system, and then used as immunogen to generate antibodies. High titers of specific antibodies were measured in serum of rabbits after the forth booster injection. And the titer of the antiserum reached 1:106. We have also generated monoclonal antibodies using hybridoma technology and the titer reached 1:105. The activity of KLK5 antibodies was characterized by Western blot and immunohistochemistry. To quantitatively examine KLK5 in serum samples, we established double antibody sandwich ELISA method using mouse mAb as capture and rabbit pAb as tracer antibody. We have detected KLK5 levels in ovarian cancer serum to ensure that our sandwich ELISA measurement to have high sensitivity and specificity. The ranges of linearity reached by the standard curves of the newly developed ELISA were 0.45 ng/mL to 125 ng/mL. The detection limit of the method, defined as the concentration of KLK5 can be distinguished, was 0.20 ng/mL. Median serum KLK5 levels were 3.77 ng/mL and 0.86 ng/mL in ovarian cancer patients and normal female, respectively (P ELISA assay for KLK5. Our preliminary findings prompt that KLK5 may be a new potential biomarker for the diagnosis and prognosis in patients with ovarian.展开更多
Proteolysis of seed storage proteins (SSP) during germination provides a steady supply of amino acids to the embryo development into seedling. This process is coordinated by different peptidases that act sequentially ...Proteolysis of seed storage proteins (SSP) during germination provides a steady supply of amino acids to the embryo development into seedling. This process is coordinated by different peptidases that act sequentially and overlaid mode. These enzymes are an ancient group evolved separately in a wide structural and functional diversity and have many applications in medicine, pharmacy and industry. However, the knowledge about seed peptidases during germination was obtained from studies almost restricted to the cultivated species. This restriction implies caution about generalizations made from these studies, as well limits the biological knowledge about plant kingdom and technological use from plant peptidases. In this work, a scan of the proteolytic activity was held in germinating seeds of a leguminous subtropical woody tree. Eleven proteolytic activities were detected in protein extracts from embryonic axis and cotyledons. The presence and intensity of these activities varied over time and between these tissues. There was indication that aspartyl-endopeptidases (phytepsins) and cysteine-carboxypeptidases (plant cathepsins) were involved in A. colubrina SSP hydrolysis. These peptidases differ to that commonly involved in germination of the cultivated leguminous. In addition, one of detected phytepsins showed stability on pH scale, which is important for industrial uses. There was also detected a metallo-carboxypeptidase activity, which has been not described in plants. These peptidases must be isolated to confirm or not these indications. However, these data indicate the biological and technological importance of extending the studies about plant peptidases on a diverse genetic basis.展开更多
A rice pse（t） （premature senescence, tentatively） mutant line, was isolated from 4500 independent T-DNA inserted transgenic lines. The symptoms of premature senescence appeared more severely than those of the cont...A rice pse（t） （premature senescence, tentatively） mutant line, was isolated from 4500 independent T-DNA inserted transgenic lines. The symptoms of premature senescence appeared more severely than those of the control plants （Zhonghua 11, japonica） at the last development stage. To characterize the mutant and provide basic information on the candidate genes by mapping to a physical region of 220-kb, experiments were carried out in two phytotrons under controlled temperature of 24 ℃ and 28 ℃, respectively. The content of chlorophyll, soluble protein and MDA （malondialdehyde）, net photosynthesis, the antioxidant enzyme activities of SOD （superoxide dismuase） （EC 1.15.1.1 ） and POD （peroxidase） （EC 1.11.1.7） and the peptidase activities of leaves were measured from top to bottom according to the leaf positions at the flowering stage. Compared with the control plant, the mutant showed the following characteristics： （1） Higher net photosynthesis rate （Pn） appeared in the 1st and 2nd leaves, contents of chlorophyll and soluble protein were also higher in the 1st leaf; （2） The activities of SOD, POD and peptidase were higher according to the leaf position from top to bottom; （3） The symptom of premature senescence was accelerated in the mutant at 28 ℃ treatment. The MDA content and the SOD and POD activities between the 24 ℃ and 28 ℃ treatment mutants were not significantly different. Content of chlorophyll and soluble protein of leaves mutant decreased rapidly at 28 ℃ treatment. The results show thatpse（t） is sensitive to high temperature. The probable function of PSE（T） is discussed.展开更多
Prostate cancer is a clinically heterogeneous disease, with some men having indolent disease that can safely be observed, while others have aggressive, lethal disease. Over the past decade, researchers have begun to u...Prostate cancer is a clinically heterogeneous disease, with some men having indolent disease that can safely be observed, while others have aggressive, lethal disease. Over the past decade, researchers have begun to unravel some of the genomic heterogeneity that contributes to these varying clinical phenotypes. Distinct molecular sub-classes of prostate cancer have been identified, and the uniqueness of these sub-classes has been leveraged to predict clinical outcomes, design novel biomarkers for prostate cancer diagnosis, and develop novel therapeutics. Recent work has also elucidated the temporal and spatial heterogeneity of prostate cancer, helping us understand disease pathogenesis, response to therapy, and progression. New genomic techniques have provided us with a window into the remarkable clinical and genomic heterogeneity of prostate cancer, and this new perspective will increasingly impact patient care.展开更多
Use of glucagon-like peptide-1 receptor agonist or dipeptidyl peptidase 4 inhibitor has been shown to lower the incidence of Parkinson's disease in patients with diabetes mellitus.Therefore,using these two treatme...Use of glucagon-like peptide-1 receptor agonist or dipeptidyl peptidase 4 inhibitor has been shown to lower the incidence of Parkinson's disease in patients with diabetes mellitus.Therefore,using these two treatments may help treat Parkinson's disease.To further investigate the mechanisms of action of these two compounds,we established a model of Parkinson's disease by treating mice with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and then subcutaneously injected them with the glucagon-like peptide-1 receptor agonist exendin-4 or the dipeptidyl peptidase 4 inhibitor linagliptin.We found that both exendin-4 and linagliptin reversed motor dysfunction,glial activation,and dopaminergic neuronal death in this model.In addition,both exendin-4 and linagliptin induced microglial polarization to the anti-inflammatory M2 phenotype and reduced pro-inflammatory cytokine secretion.Moreover,in vitro experiments showed that treatment with exendin-4 and linagliptin inhibited activation of the nucleotide-binding oligomerization domain-and leucine-rich-repeat-and pyrin-domaincontaining 3/caspase-1/interleukin-1βpathway and subsequent pyroptosis by decreasing the production of reactive oxygen species.These findings suggest that exendin-4 and linagliptin exert neuroprotective effects by attenuating neuroinflammation through regulation of microglial polarization and the nucleotidebinding oligomerization domain-and leucine-rich-repeat-and pyrin-domain-containing 3/caspase-1/interleukin-1βpathway in a mouse model of Parkinson's disease induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine.Therefore,these two drugs may serve as novel anti-inflammatory treatments for Parkinson's disease.展开更多
Diabetes is the most important risk factors for chronic kidney disease(CKD). The risk of CKD attributable to diabetes continues to rise worldwide. Diabetic patients with CKD need complicated treatment for their metabo...Diabetes is the most important risk factors for chronic kidney disease(CKD). The risk of CKD attributable to diabetes continues to rise worldwide. Diabetic patients with CKD need complicated treatment for their metabolic disorders as well as for related comorbidities. They have to treat, often intensively, hypertension, dyslipidaemia, bone disease, anaemia, and frequently established cardiovascular disease. The treatment of hypoglycaemia in diabetic persons with CKD must tie their individual goals of glycaemia(usually less tight glycaemic control) and knowledge on the pharmacokinetics and pharmacodynamics of drugs available to a person with kidney disease. The problem is complicated from the fact that in many efficacy studies patients with CKD are excluded so data of safety and efficacy for these patients are missing. This results in fear of use by lack of evidence. Metformin is globally accepted as the first choice in practically all therapeutic algorithms for diabetic subjects. The advantages of metformin are low risk of hypoglycaemia, modest weight loss, effectiveness and low cost. Data of UKPDS indicate that treatment based on metformin results in less total as well cardiovascular mortality. Metformin remains the drug of choice for patients with diabetes and CKD provided that their estimate Glomerular Filtration Rate(eGFR) remains above 30 mL/min per square meter. For diabetic patients with eGFR between 30-60 mL/min per square meter more frequent monitoring of renal function and dose reduction of metformin is needed. The use of sulfonylureas, glinides and insulin carry a higher risk of hypoglycemia in these patients and must be very careful. Lower doses and slower titration of the dose is needed. Is better to avoid sulfonylureas with active hepatic metabolites, which are renally excreted. Very useful drugs for this group of patients emerge dipeptidyl peptidase 4 inhibitors. These drugs do not cause hypoglycemia and most of them(linagliptin is an exception) require dose reduction in various stages of renal disease.展开更多
AIM To study the effects of linagliptin on the structural signs of non-alcoholic fatty liver disease(NAFLD) in db/db mice. METHODS Male diabetic db /db mice(BKS.Cg-Dock7m+/+Leprdb/J) aged 10 wk received the dipeptidyl...AIM To study the effects of linagliptin on the structural signs of non-alcoholic fatty liver disease(NAFLD) in db/db mice. METHODS Male diabetic db /db mice(BKS.Cg-Dock7m+/+Leprdb/J) aged 10 wk received the dipeptidyl peptidase 4(DPP4) inhibitor linagliptin(10 mg/kg) or saline as a placebo once per day by gavage for 8 wk. Intact db/db mice served as controls. Structural changes in the liver were analyzed from light and electron microscopic images of sections from intact, placebo-treated and linagliptin-treated animals. We estimated the changes in hepatocytes, sinusoidal cells, liver microvasculature and lymphatic roots. Hepatic staining for lymphatic vessel endothelial hyaluronan receptor-1(LYVE-1) was assessed by immunohistochemistry. RESULTS In 18-wk-old diabetic mice, liver steatosis(predominantly microvesicular and mediovesicular steatosis) was accompanied by dilation of the roots of the lymphatic system, interlobular blood vessels and bile canaliculi. Compared to saline-treated mice, linagliptin-treated mice exhibited a reduction in the mean numeral densities of hepatocytes with lipid droplets(92.4% ± 1.7% vs 64.9% ± 5.8% per field of view, P = 0.0002) and a lower proportion of hepatocytes with a high density of lipid droplets(20.7% ± 3.6% vs 50.4% ± 3.1%, P = 0.0007). We observed heterogeneous hepatocytes and relatively preserved cell structures in the linagliptin group. Dilation of blood and lymphatic vessels, as well as ultrastructural changes in the hepatocyte endoplasmic reticulum and mitochondria, were alleviated by linagliptin treatment. In intact and placebo-treated mice, immunohistochemical staining for LYVE-1 was observed in the endothelial cells of interlobular lymphatic vessels and on the membranes of some endothelial sinusoidal cells. We observed an enlarged LYVE-1 reaction area in linagliptin-treated mice compared to intact and placebo-treated mice. The improvement in the structural parameters of the liver in linagliptin-treated mice was independent to changes in the plasma glucose levels. CONCLUSION The DPP4 inhibitor linagliptin alleviates liver steatosis and structural changes in the hepatic microvasculature and lymphatic roots in a model of NAFLD in diabetic db/db mice.展开更多
Current experimental stroke research has evolved to focus on detailed understanding of the brain’s self-protective and restorative mechanisms,and harness this knowledge for development of new therapies.In this contex...Current experimental stroke research has evolved to focus on detailed understanding of the brain’s self-protective and restorative mechanisms,and harness this knowledge for development of new therapies.In this context,the role of peptidases and neuropeptides is of growing interest.In this focused review,peptidase neurolysin(Nln)and its extracellular peptide substrates are briefly discussed in relation to pathophysiology of ischemic stroke.Upregulation of Nln following stroke is viewed as a compensatory cerebroprotective mechanism in the acute phase of stroke,because the main neuropeptides inactivated by Nln are neuro/cerebrotoxic(bradykinin,substance P,neurotensin,angiotensin II,hemopressin),whereas the peptides generated by Nln are neuro/cerebroprotective(angiotensin-(1–7),Leu-/Met-enkephalins).This notion is confirmed by experimental studies documenting aggravation of stroke outcomes in mice after inhibition of Nln following stroke,and dramatic improvement of stroke outcomes in mice overexpressing Nln in the brain.The role of Nln in the(sub)chronic phase of stroke is less clear and it is likely,that this peptidase does not have a major role in neural repair mechanisms.This is because,the substrates of Nln are less uniform in modulating neurorestorative mechanisms in one direction,some appearing to have neural repair enhancing/stimulating potential,whereas others doing the opposite.Future studies focusing on the role of Nln in pathophysiology of stroke should determine its potential as a cerebroprotective target for stroke therapy,because its unique ability to modulate multiple neuropeptide systems critically involved in brain injury mechanisms is likely advantageous over modulation of one pathogenic pathway for stroke pharmacotherapy.展开更多
基金Supported by Colegio de Ciencia y Tecnologia de la Universidad Autónoma de la Ciudad de México,No.UACM-CCyT-2025-CON-11.
文摘Proteases are essential for homeostasis,and their primary function is proteolytic in extracellular and intracellular compartments.The deregulation of expression,abundance,and activity of proteases has been related to several pathologies,including cancer.This deregulation contributes to their pro-tumorigenic activity since they participate in the degradation of extracellular matrix components and adhesion molecules,and the activation of growth factors.However,some proteases,such as ADAM metallopeptidase with thrombospondin type 1 motif 8 and kallikrein-related peptidases 5 and 10,have emerged as tumor suppressors due to their antitumoral actions in specific cancer contexts.In this article,we discuss the antitumoral effects of ADAM metallopeptidase with thrombospondin type 1 motif 8,kallikrein-related peptidases 5 and 10 that have been described to date,suggesting their potential use as novel biomarkers and therapeutic targets in cancer.
文摘BACKGROUND Colorectal cancer(CRC)is the third most frequent and the second most fatal cancer.The search for more effective drugs to treat this disease is ongoing.A better understanding of the mechanisms of CRC development and progression may reveal new therapeutic strategies.Ubiquitin-specific peptidases(USPs),the largest group of the deubiquitinase protein family,have long been implicated in various cancers.There have been numerous studies on the role of USPs in CRC;however,a comprehensive view of this role is lacking.AIM To provide a systematic review of the studies investigating the roles and functions of USPs in CRC.METHODS We systematically queried the MEDLINE(via PubMed),Scopus,and Web of Science databases.RESULTS Our study highlights the pivotal role of various USPs in several processes implicated in CRC:Regulation of the cell cycle,apoptosis,cancer stemness,epithelial–mesenchymal transition,metastasis,DNA repair,and drug resistance.The findings of this study suggest that USPs have great potential as drug targets and noninvasive biomarkers in CRC.The dysregulation of USPs in CRC contributes to drug resistance through multiple mechanisms.CONCLUSION Targeting specific USPs involved in drug resistance pathways could provide a novel therapeutic strategy for overcoming resistance to current treatment regimens in CRC.
文摘In this present work, the best conditions for production of peptidases under solid state fermentation by the fungi Penicillium corylophilum and Penicillium waksmanii, partial purification using Sephadex G-75 gel filtration column, as well as the biochemical characterization of the partial purified enzymes were investigated. P. corylophilum showed the best production in medium containing wheat bran, agro-industrial residue, without additives （egg albumin or casein）, in which peptidase activity reached 520 U mL^-1 and the enzyme displayed the optimum activity between pH range from 7 to 8 and 60 ℃. It also showed high stability in wide pH range and temperature until 45 ℃ for 60 min of incubation. On the other hand, P. waksmanii, the best production was noted in a medium containing wheat bran （95%） and casein （5%）, reaching 545 U mL^-1, with proteolytic optimum activity at pH 7.5 and 55 ℃. The enzyme was mainly stable in pH range from 8 to 9 and at temperatures until 45 ℃ for 60 rain of incubation. The peptidases secreted by both fungi were inhibited in the presence of phenylmethane sulfonyl fluoride, showing that they belong to the subclass of serine peptidases.
文摘While exerting their metabolic activities in the gastrointestinal milieu,probiotics impact the host well-being by boosting immunity,treating metabolic disorders,and modulating microbiota and metabolome.Due to the high incidence of gluten-based disorders,the present work aims to deeply explore the metabolism of two selected microbial consortia(MCs)during gluten digestion under simulated gastrointestinal conditions.Featured by high protease and peptidase activity,both MCs accounted for different lactic acid bacteria and Bacillus strains that were combined with two commercial protease enzymes.Gluten substrates were used as purified extracts,white and whole wheat breads.Control samples,instead,relied onto the microbial enzyme lack.Twenty-four hours of simulated digestion were sufficient to completely hydrolyze gluten in one of the two MC-containing experimental sets,and the relative 48 h-digested extract did not alter the cytokine expression in duodenal biopsies from celiac disease(CeD)patients.When digested samples were assayed for antioxidant and phytase activities,microbial enzymes demonstrated to significantly improve both 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)and 1,1-diphenyl-2-picrylhydrazyl(DPPH)scavenging activity and to decrease the phytic acid concentration.The inspection of the free amino acid profiles allowed for distinguishing the two MCs,whereas the detection of a heterogeneous panel of volatile organic compounds supported the presence/activity of microbial enzymes without statistically significant differences between MCs.As functional contribution,digested extracts with MCs also proved to reduce the inflammatory cytokine concentrations in cell lines exposed to lipopolysaccharide trigger.Therefore,in line with studies exploring novel adjuvant therapies,the present innovative probiotic consortium featured by high gluten-hydrolyzing metabolism also showed the capability to improve various parameters usually found to be altered in patients affected by gluten-based disorders or CeD.
基金supported by the Clinical Frontier Technology Program of the First Affiliated Hospital of Jinan University,China(No.JNU1AF-CFTP-2022-a01223)Guangzhou Science and Technology Plan City-School Joint Funding Project(2024A03J0825)+2 种基金Science and Technology Projects in Guangzhou(202201020566)Medical Joint Fund of Jinan University(YXJC2022005)the Fundamental Research Funds for the Central Universities(21623319).
文摘Background: Tumor angiogenesis is related to solid tumor occurrence. Ubiquitin-specific peptidase 13 (USP13) is a deubiquitinating enzyme with a pivotal effect on tumor proliferation, metastasis, and tumorigenesis. Nonetheless, its effect on colorectal cancer (CRC) angiogenesis remains poorly understood. Methods: Human umbilical vein endothelial cells (HUVECs) and CRC cells were cultivated, followed by USP13 knockdown/overexpression using shRNA lentiviral vectors or plasmids. Conditioned media (CM) from treated CRC cells were collected to assess HUVEC migration, invasion, and tube formation. Phosphatase and tensin homolog (PTEN) overexpression and recombinant vascular endothelial growth factor A (VEGFA) rescue experiments were performed. Molecular mechanisms were analyzed via Western blot (PTEN, p-AKT, VEGFA), co-immunoprecipitation (PTEN ubiquitination), and in vivo nude mice study to detect the role of USP13 in tumor angiogenesis. Results: USP13 expression in CRC cells is downregulated and negatively related to platelet endothelial cell adhesion molecule-1 (CD31) expression. Furthermore, the conditioned medium from CRC cells with USP13 knockdown significantly promoted HUVEC migration, invasion, and tube formation, while USP13 overexpression exerted the opposite effect. Additionally, USP13 overexpression significantly increased PTEN expression while decreasing protein kinase B (AKT) phosphorylation levels. Concurrently, USP13 overexpression significantly reduced PTEN ubiquitination, whereas USP13 knockdown remarkably increased this modification. Overexpression of PTEN in sh-USP13 CRC cells decreased the expression levels of VEGFA and p-AKT. USP13 also inhibited tumor angiogenesis through downregulating VEGFA, and recombinant VEGFA blocked the inhibition of the conditioned medium from USP13-overexpressing CRC cells against HUVEC angiogenesis in vivo. Conclusions: USP13 downregulated VEGFA and inhibited tumor angiogenesis via the PTEN-AKT pathway.
基金Supported by the National Natural Science Foundation of China,No.82103173 and No.82460461Medical Subject Leader of Yunnan Province(General Surgery),No.D-2024029+1 种基金Yunnan Fundamental Research Project for Excellent Young Scholars,No.202401AW070003the Young and Mid-aged Academic and Technical Leader Reserve Talent Program of Yunnan Province,No.202205AC160063。
文摘This letter comments on the recently published manuscript by Yu et al,in which the authors revealed a novel mechanism by which the m6A-modified long noncoding RNA kinesin family member 9-antisense RNA 1 promotes stemness and sorafenib resistance of hepatocellular carcinoma(HCC)through ubiquitinspecific peptidase 1-mediated deubiquitination of oncogene short stature homeobox 2.Given the high mortality rate and poor prognosis of HCC,the findings by Yu et al open a new avenue for overcoming HCC burden by focusing on kinesin family member 9-antisense RNA 1 and short stature homeobox 2 as prognostic markers and therapeutic targets.
基金This work was supported by the German Research Foundation(DFG)and the Technical University of Munich(TUM)in the framework of the Open Access Publishing Program.
文摘Background:Alterations in the expression of human kallikrein-related peptidases(KLKs)have been described in patients with Alzheimer’s disease(AD).We elucidated the suitability of KLK6,KLK8 and KLK10 to distinguish AD from NC and explored associations with established AD biomarkers.Methods:KLK levels in cerebrospinal fluid(CSF),as determined by ELISA,were compared between 32 AD patients stratified to A/T/(N)system with evidence for amyloid pathology and of 23 normal controls with normal AD biomarkers.Associations between KLK levels and clinical severity,CSF and positron emission tomography(PET)based AD biomarkers were tested for.Results:Levels of KLK6 and KLK10 were significantly increased in AD.KLK6 differed significantly between AD A+/T+/N+and AD A+/T−/N+or NC with an AUC of 0.922.CSF pTau and tTau levels were significantly associated with KLK6 in AD.Conclusions:KLK6 deserves further investigations as a potential biomarker of Tau pathology in AD.
文摘Peptidases are essential for intracellular protein processing,signaling and homeostasis,physiological processes and for digestion of food.Moreover,peptidases are important biotechnological enzymes used in processes such as industrial food processing,leather manufacturing and the washing industry.Identification of peptidases is a crucial step in their characterization but peptidase annotation is not a trivial task due to their large sequence diversity.In the present study short,conserved sequence profiles were generated for all peptidase families with more than four members in the comprehensive Merops peptidase database.The sequence profiles were combined with the Homology to Peptide Pattern(Hotpep)method for automatic annotation of peptidases.This method is a standalone software that annotates protease sequences to Merops family and subgroup and is suitable for large-scale sequence analysis.Compared to the Mammalian Degradome Database Hotpep-protease had an accuracy of 92%and a sensitivity of 96%for annotation of the human degradome.Annotation by commonly used methods(Blast and conserved domains)had an accuracy of 69%and a sensitivity of 78%.For fungal genomes,there were large differences between annotation with Hotpep-protease,Blast-and Hidden Markov Model-based annotation and the Merops annotation,which confirms the difficulty of large-scale peptidase annotation.Manual annotation indicated that Hotpep-protease had a positive prediction rate of 0.90 compared to a positive prediction rate of 0.67 for Blast search.Hence,Hotpep-protease is highly accurate method for fast and accurate annotation of peptidases.
基金supported by Shanghai Pujiang Program(No.20PJ1413000)the National Natural Science Foundation of China(No.82173106,82130115,81290108033,82004004,and 82074011)。
文摘The management of colorectal cancer(CRC)poses a significant challenge,necessitating the development of innovative and effective therapeutics.Our research has shown that notoginsenoside Ft1(Ng-Ft1),a small molecule,markedly inhibits subcutaneous tumor formation in CRC and enhances the proportion of CD8^(+)T cells in tumor-bearing mice,thus restraining tumor growth.Investigation into the mechanism revealed that Ng-Ft1 selectively targets the deubiquitination enzyme USP9X,undermining its role in shieldingβ-catenin.This leads to a reduction in the expression of downstream effectors in the Wnt signaling pathway.These findings indicate that Ng-Ft1 could be a promising small-molecule treatment for CRC,working by blocking tumor progression via the Wnt signaling pathway and augmenting CD8^(+)T cell prevalence within the tumor environment.
基金Supported by Ruian Natural Science Foundation,No.MS2021008.
文摘BACKGROUND Serpin peptidase inhibitor clade H member 1(SERPINH1)was initially recognized as an oncogene implicated in various human malignancies.Nevertheless,the clinical relevance and functional implications of SERPINH1 in colorectal cancer(CRC)remain largely elusive.AIM To investigate the effects of SERPINH1 on CRC cells and its specific mechanism.METHODS Quantitative real-time polymerase chain reaction,western blotting analysis,The Cancer Genome Atlas data mining and immunohistochemistry were employed to examine SERPINH1 expression in CRC cell lines and tissues.A series of in-vitro assays were performed to demonstrate the function of SERPINH1 and its possible mechanisms in CRC.RESULTS SERPINH1 demonstrated elevated expression levels in both CRC cells and tissues,manifested at both mRNA and protein tiers.Elevated SERPINH1 levels correlated closely with advanced T stage,lymph node involvement,and distant metastasis,exhibiting a significant association with poorer overall survival among CRC patients.Subsequent investigations unveiled that SERPINH1 overexpression notably bolstered CRC cell proliferation,invasion,and migration in vitro,while conversely,SERPINH1 knockdown elicited the opposite effects.Gene set enrichment analysis underscored a correlation between SERPINH1 upregulation and genes associated with cell cycle regulation.Our findings underscored the capacity of heightened SERPINH1 levels to expedite G1/S phase cell cycle progression via phosphatidylinositol 3-kinase/AKT/mechanistic target of rapamycin pathway activation,thereby facilitating CRC cell invasion and migration.CONCLUSION These findings imply a crucial involvement of SERPINH1 in the advancement and escalation of CRC,potentially positioning it as a novel candidate for prognostic assessment and therapeutic intervention in CRC management.
文摘AIM: Cysteine peptidase (CP) and its inhibitor (CPI) are a matrix protease that may be associated with colorectal carcinoma invasion and progression, and vitamin E is also a stimulator of the immunological system. Our purpose was to determine the correlation between the expression of cysteine peptidases and their endogenous inhibitors,and the level of vitamin E in sera of patients with colorectal cancer in comparison with healthy individuals.METHODS: The levels of cysteine peptidases and their inhibitors were determined in the sera of patients with primary and metastatic colorectal carcinoma and healthy individuals using fluorogenic substrate, and the level of vitamin E was determined by HPLC.RESULTS: The levels of cysteine peptidases and their inhibitors were significantly higher in the metastatic colorectal cancer patients than that in the healthy controls (P＜0.05).The activity of CP increased 2.2-fold, CPI 2.8-fold and vitamin E decreased 3.4-fold in sera of patients with metastasis in comparison with controls. The level of vitamin E in healthy individuals was higher, whereas the activity of cysteine peptidases and their inhibitors associated with complexes was lower than that in patients with cancer of the digestive tract.CONCLUSION: These results suggest that the serum levels of CP and their inhibitors could be an indicator of the prognosis for patients with metastatic colorectal cancer. Vitamin E can be administered prophylactically to prevent digestive tract neoplasmas.
文摘Kallikrein-related peptidases (KLKs) have been proposed as potential cancer biomarkers. Kallikrein-related peptidase 5 (KLK5) is a secreted trypsin-like protease of the KLKs. Until now, detection of KLK5 in both biological fluids and tissues has been described frequently due to the potential of being a new cancer biomarker. Our objective was to prepare KLK5 antibodies and establish an ELISA method for KLK5 to study the possible clinical application of KLK5 as a biomarker for malignancies. In this study, recombinant KLK5 protein was produced and purified using a prokaryotic expression system, and then used as immunogen to generate antibodies. High titers of specific antibodies were measured in serum of rabbits after the forth booster injection. And the titer of the antiserum reached 1:106. We have also generated monoclonal antibodies using hybridoma technology and the titer reached 1:105. The activity of KLK5 antibodies was characterized by Western blot and immunohistochemistry. To quantitatively examine KLK5 in serum samples, we established double antibody sandwich ELISA method using mouse mAb as capture and rabbit pAb as tracer antibody. We have detected KLK5 levels in ovarian cancer serum to ensure that our sandwich ELISA measurement to have high sensitivity and specificity. The ranges of linearity reached by the standard curves of the newly developed ELISA were 0.45 ng/mL to 125 ng/mL. The detection limit of the method, defined as the concentration of KLK5 can be distinguished, was 0.20 ng/mL. Median serum KLK5 levels were 3.77 ng/mL and 0.86 ng/mL in ovarian cancer patients and normal female, respectively (P ELISA assay for KLK5. Our preliminary findings prompt that KLK5 may be a new potential biomarker for the diagnosis and prognosis in patients with ovarian.
文摘Proteolysis of seed storage proteins (SSP) during germination provides a steady supply of amino acids to the embryo development into seedling. This process is coordinated by different peptidases that act sequentially and overlaid mode. These enzymes are an ancient group evolved separately in a wide structural and functional diversity and have many applications in medicine, pharmacy and industry. However, the knowledge about seed peptidases during germination was obtained from studies almost restricted to the cultivated species. This restriction implies caution about generalizations made from these studies, as well limits the biological knowledge about plant kingdom and technological use from plant peptidases. In this work, a scan of the proteolytic activity was held in germinating seeds of a leguminous subtropical woody tree. Eleven proteolytic activities were detected in protein extracts from embryonic axis and cotyledons. The presence and intensity of these activities varied over time and between these tissues. There was indication that aspartyl-endopeptidases (phytepsins) and cysteine-carboxypeptidases (plant cathepsins) were involved in A. colubrina SSP hydrolysis. These peptidases differ to that commonly involved in germination of the cultivated leguminous. In addition, one of detected phytepsins showed stability on pH scale, which is important for industrial uses. There was also detected a metallo-carboxypeptidase activity, which has been not described in plants. These peptidases must be isolated to confirm or not these indications. However, these data indicate the biological and technological importance of extending the studies about plant peptidases on a diverse genetic basis.
基金Project supported by the National Basic Research Program (973) of China (No. G19990116-1)the High-Tech Research and Develop-ment Program (863) of China (No. 2002AA2Z1001)the State Key Laboratory of Rice Biology and partly granted (Nos. 30471051 and 30470933) from National Natural Science Foundation of China
文摘A rice pse（t） （premature senescence, tentatively） mutant line, was isolated from 4500 independent T-DNA inserted transgenic lines. The symptoms of premature senescence appeared more severely than those of the control plants （Zhonghua 11, japonica） at the last development stage. To characterize the mutant and provide basic information on the candidate genes by mapping to a physical region of 220-kb, experiments were carried out in two phytotrons under controlled temperature of 24 ℃ and 28 ℃, respectively. The content of chlorophyll, soluble protein and MDA （malondialdehyde）, net photosynthesis, the antioxidant enzyme activities of SOD （superoxide dismuase） （EC 1.15.1.1 ） and POD （peroxidase） （EC 1.11.1.7） and the peptidase activities of leaves were measured from top to bottom according to the leaf positions at the flowering stage. Compared with the control plant, the mutant showed the following characteristics： （1） Higher net photosynthesis rate （Pn） appeared in the 1st and 2nd leaves, contents of chlorophyll and soluble protein were also higher in the 1st leaf; （2） The activities of SOD, POD and peptidase were higher according to the leaf position from top to bottom; （3） The symptom of premature senescence was accelerated in the mutant at 28 ℃ treatment. The MDA content and the SOD and POD activities between the 24 ℃ and 28 ℃ treatment mutants were not significantly different. Content of chlorophyll and soluble protein of leaves mutant decreased rapidly at 28 ℃ treatment. The results show thatpse（t） is sensitive to high temperature. The probable function of PSE（T） is discussed.
文摘Prostate cancer is a clinically heterogeneous disease, with some men having indolent disease that can safely be observed, while others have aggressive, lethal disease. Over the past decade, researchers have begun to unravel some of the genomic heterogeneity that contributes to these varying clinical phenotypes. Distinct molecular sub-classes of prostate cancer have been identified, and the uniqueness of these sub-classes has been leveraged to predict clinical outcomes, design novel biomarkers for prostate cancer diagnosis, and develop novel therapeutics. Recent work has also elucidated the temporal and spatial heterogeneity of prostate cancer, helping us understand disease pathogenesis, response to therapy, and progression. New genomic techniques have provided us with a window into the remarkable clinical and genomic heterogeneity of prostate cancer, and this new perspective will increasingly impact patient care.
基金supported by the National Natural Science Foundation of China,Nos.81771271(to JF),31800898(to WL),81430025(to JYL),and U1801681(to JYL)Key Research and Development Program of Liaoning Province,No.2020JH2/10300047(to JF)+1 种基金the Key Field Research Development Program of Guangdong Province,No.2018B030337001(to JYL)the Outstanding Scientific Fund of Shengjing Hospital,No.M0475(to JF)。
文摘Use of glucagon-like peptide-1 receptor agonist or dipeptidyl peptidase 4 inhibitor has been shown to lower the incidence of Parkinson's disease in patients with diabetes mellitus.Therefore,using these two treatments may help treat Parkinson's disease.To further investigate the mechanisms of action of these two compounds,we established a model of Parkinson's disease by treating mice with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and then subcutaneously injected them with the glucagon-like peptide-1 receptor agonist exendin-4 or the dipeptidyl peptidase 4 inhibitor linagliptin.We found that both exendin-4 and linagliptin reversed motor dysfunction,glial activation,and dopaminergic neuronal death in this model.In addition,both exendin-4 and linagliptin induced microglial polarization to the anti-inflammatory M2 phenotype and reduced pro-inflammatory cytokine secretion.Moreover,in vitro experiments showed that treatment with exendin-4 and linagliptin inhibited activation of the nucleotide-binding oligomerization domain-and leucine-rich-repeat-and pyrin-domaincontaining 3/caspase-1/interleukin-1βpathway and subsequent pyroptosis by decreasing the production of reactive oxygen species.These findings suggest that exendin-4 and linagliptin exert neuroprotective effects by attenuating neuroinflammation through regulation of microglial polarization and the nucleotidebinding oligomerization domain-and leucine-rich-repeat-and pyrin-domain-containing 3/caspase-1/interleukin-1βpathway in a mouse model of Parkinson's disease induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine.Therefore,these two drugs may serve as novel anti-inflammatory treatments for Parkinson's disease.
文摘Diabetes is the most important risk factors for chronic kidney disease(CKD). The risk of CKD attributable to diabetes continues to rise worldwide. Diabetic patients with CKD need complicated treatment for their metabolic disorders as well as for related comorbidities. They have to treat, often intensively, hypertension, dyslipidaemia, bone disease, anaemia, and frequently established cardiovascular disease. The treatment of hypoglycaemia in diabetic persons with CKD must tie their individual goals of glycaemia(usually less tight glycaemic control) and knowledge on the pharmacokinetics and pharmacodynamics of drugs available to a person with kidney disease. The problem is complicated from the fact that in many efficacy studies patients with CKD are excluded so data of safety and efficacy for these patients are missing. This results in fear of use by lack of evidence. Metformin is globally accepted as the first choice in practically all therapeutic algorithms for diabetic subjects. The advantages of metformin are low risk of hypoglycaemia, modest weight loss, effectiveness and low cost. Data of UKPDS indicate that treatment based on metformin results in less total as well cardiovascular mortality. Metformin remains the drug of choice for patients with diabetes and CKD provided that their estimate Glomerular Filtration Rate(eGFR) remains above 30 mL/min per square meter. For diabetic patients with eGFR between 30-60 mL/min per square meter more frequent monitoring of renal function and dose reduction of metformin is needed. The use of sulfonylureas, glinides and insulin carry a higher risk of hypoglycemia in these patients and must be very careful. Lower doses and slower titration of the dose is needed. Is better to avoid sulfonylureas with active hepatic metabolites, which are renally excreted. Very useful drugs for this group of patients emerge dipeptidyl peptidase 4 inhibitors. These drugs do not cause hypoglycemia and most of them(linagliptin is an exception) require dose reduction in various stages of renal disease.
基金Supported by Grants from the Russian Ministry of Education and Science,Nos.14.621.21.0010,RFMEFI62114X0010 and14.619.21.0005,RFMEFI61914X0005
文摘AIM To study the effects of linagliptin on the structural signs of non-alcoholic fatty liver disease(NAFLD) in db/db mice. METHODS Male diabetic db /db mice(BKS.Cg-Dock7m+/+Leprdb/J) aged 10 wk received the dipeptidyl peptidase 4(DPP4) inhibitor linagliptin(10 mg/kg) or saline as a placebo once per day by gavage for 8 wk. Intact db/db mice served as controls. Structural changes in the liver were analyzed from light and electron microscopic images of sections from intact, placebo-treated and linagliptin-treated animals. We estimated the changes in hepatocytes, sinusoidal cells, liver microvasculature and lymphatic roots. Hepatic staining for lymphatic vessel endothelial hyaluronan receptor-1(LYVE-1) was assessed by immunohistochemistry. RESULTS In 18-wk-old diabetic mice, liver steatosis(predominantly microvesicular and mediovesicular steatosis) was accompanied by dilation of the roots of the lymphatic system, interlobular blood vessels and bile canaliculi. Compared to saline-treated mice, linagliptin-treated mice exhibited a reduction in the mean numeral densities of hepatocytes with lipid droplets(92.4% ± 1.7% vs 64.9% ± 5.8% per field of view, P = 0.0002) and a lower proportion of hepatocytes with a high density of lipid droplets(20.7% ± 3.6% vs 50.4% ± 3.1%, P = 0.0007). We observed heterogeneous hepatocytes and relatively preserved cell structures in the linagliptin group. Dilation of blood and lymphatic vessels, as well as ultrastructural changes in the hepatocyte endoplasmic reticulum and mitochondria, were alleviated by linagliptin treatment. In intact and placebo-treated mice, immunohistochemical staining for LYVE-1 was observed in the endothelial cells of interlobular lymphatic vessels and on the membranes of some endothelial sinusoidal cells. We observed an enlarged LYVE-1 reaction area in linagliptin-treated mice compared to intact and placebo-treated mice. The improvement in the structural parameters of the liver in linagliptin-treated mice was independent to changes in the plasma glucose levels. CONCLUSION The DPP4 inhibitor linagliptin alleviates liver steatosis and structural changes in the hepatic microvasculature and lymphatic roots in a model of NAFLD in diabetic db/db mice.
基金This work was partly supported by research grants from the American Heart Association(14BGIA20380826)National Institutes of Health(1R01NS106879).
文摘Current experimental stroke research has evolved to focus on detailed understanding of the brain’s self-protective and restorative mechanisms,and harness this knowledge for development of new therapies.In this context,the role of peptidases and neuropeptides is of growing interest.In this focused review,peptidase neurolysin(Nln)and its extracellular peptide substrates are briefly discussed in relation to pathophysiology of ischemic stroke.Upregulation of Nln following stroke is viewed as a compensatory cerebroprotective mechanism in the acute phase of stroke,because the main neuropeptides inactivated by Nln are neuro/cerebrotoxic(bradykinin,substance P,neurotensin,angiotensin II,hemopressin),whereas the peptides generated by Nln are neuro/cerebroprotective(angiotensin-(1–7),Leu-/Met-enkephalins).This notion is confirmed by experimental studies documenting aggravation of stroke outcomes in mice after inhibition of Nln following stroke,and dramatic improvement of stroke outcomes in mice overexpressing Nln in the brain.The role of Nln in the(sub)chronic phase of stroke is less clear and it is likely,that this peptidase does not have a major role in neural repair mechanisms.This is because,the substrates of Nln are less uniform in modulating neurorestorative mechanisms in one direction,some appearing to have neural repair enhancing/stimulating potential,whereas others doing the opposite.Future studies focusing on the role of Nln in pathophysiology of stroke should determine its potential as a cerebroprotective target for stroke therapy,because its unique ability to modulate multiple neuropeptide systems critically involved in brain injury mechanisms is likely advantageous over modulation of one pathogenic pathway for stroke pharmacotherapy.
