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1.
Curr Med Chem ; 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34525910

RESUMO

Prolyl-specific peptidases or proteases, including Dipeptidyl Peptidase 2, 4, 6, 8, 9, 10, Fibroblast Activation Protein, prolyl endopeptidase and prolyl carboxypeptidase, belong to the dipeptidyl peptidase family. In human physiology and anatomy, they have homology amino acid sequences, similarities in structure, but play distinct functions and roles. Some of them also play important roles in the metabolism of drugs containing endogenous peptides, xenobiotics containing peptides, and exogenous peptides. The major functions of these peptidases in both the metabolism of human health and bioactive peptides are of significant importance in the development of effective inhibitors to control the metabolism of endogenous bioactive peptides. The structural characteristics, distribution of tissue, endogenous substrates, and biological functions were summarized in this review. Furthermore, the xenobiotics metabolism of the dipeptidyl peptidase family is illustrated. All the evidence and information summarized in this review would be very useful for researchers to extend the understanding of the proteins of these families and offer advice and assistance in physiology and pathology studies.

2.
Protein Pept Lett ; 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34551686

RESUMO

BACKGROUND: Sanghuangporus baumii is a traditional Chinese medicine with anti-cancer, anti-tumor, and anti-inflammatory effects. Triterpenoids are one of the main medicinal ingredients found in S. baumii. However, the dynamic changes of triterpenoids content and its molecular regulation mechanism are still unclear. OBJECTIVE: Some studies have shown that Lanosterol synthase (LS) is a key enzyme involved in the mevalonate pathway (MVA pathway) to produce lanosterol, which is a precursor for synthesizing S. baumii triterpenoids. Therefore, the study of LS gene and expression characteristics can provide clues for the further study of triterpenoids synthesis. METHODS: The PCR, RACE PCR, RT-PCR, seamless cloning and prokaryotic expression technology were used to research the gene characteristic and dynamic changes of LS transcription level. RESULTS: The S. baumii LS sequence included a 5'-untranslated region (129 bp), a 3'-untranslated region (87 bp), and an open reading frame (2,229 bp) encoding 734 amino acids. The S. baumii LS protein was expressed in E. coli BL21 (DE3). The transcription start site of the S. baumii LS promoter sequence ranged from 1 740 bp to 1790 bp. The LS promoter contained 12 CAAT-boxes, 5 ABREs, 6 G-Boxes, 6 CGTCA-motifs, and so on. The LS transcription levels were the highest on day 11 in mycelia (1.6-fold), and the triterpenoids content also gradually increased. The transcription levels began to decrease on day 13, but the triterpenoids content still increased. CONCLUSION: The S. baumii LS was cloned and characterized to help to understand the mechanism of triterpenoids synthesis. In addition, we studied the relationship between LS transcription level and triterpenoid dynamic accumulation, and we found that they had a certain correlation.

3.
Stem Cells Dev ; 30(19): 991-1002, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34470469

RESUMO

We previously reported that cytoprotective Heme oxygenase-1, HO-1 (HMOX1) gene-modified human placenta-derived mesenchymal stem cell (HO-1-PMSC) improved placental vascularization in vitro. In the current study, we explored the protective benefit of HO-1-PMSC transplantation in a preeclampsia (PE)-like rat model. A model of PE was successfully constructed by intraperitoneal injection of N-nitro-L-arginine methyl ester (L-NAME). Blood pressure and urinary protein levels were measured. Doppler ultrasound was examined to understand uteroplacental perfusion. ELISA was used to examine the serum levels of VEGF, PlGF, sFlt-1, and sEng. The placentas and fetuses were weighed to verify the improvement in pregnancy outcome. Immunohistochemical and H&E staining was used to detect microvessel density (MVD) in placental tissues and kidney pathology, respectively. The distribution of GFP-labeled PMSC in the placenta were observed under fluorescence microscopy. Blood pressure and proteinuria were reduced and kidney damage was improved. PE rat models treated with PMSC and HO-1-PMSC exhibited an increase in the quality of fetuses and placentas, MVD, VEGF, and PlGF expression, but substantially decreased expression of sFlt-1 and sEng. Doppler ultrasound showed that the placental perfusion was improved. Green fluorescent tracing experiments verified that the cells were successfully transplanted into the placenta and distributed in the blood vessels, indicating that the cells might participate in the process of angiogenesis. These results indicate that therapy with HO-1-PMSC could improve placental vascular dysplasia, increase placental perfusion, control PE symptoms, and promote pregnancy outcome by regulating the balance of angiogenic and antiangiogenic factors or directly participating in the repair of placental vessels in a PE-like rat model.

4.
Ginekol Pol ; 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34541650

RESUMO

OBJECTIVES: This study aimed to explore the effect of interdisciplinary and diversified health education combined with personalized nutrition intervention on FPG, 2hPG, SDS, SAS scores and pregnancy outcome of gestational diabetes mellitus (GDM). MATERIAL AND METHODS: A total of 180 GDM patients, who were admitted to our hospital between June 2019 and June 2020, were enrolled as the research subjects and randomly divided into two groups: a research group and a control group (n = 90, each). The patients in the control group received routine care while the patients in the research group received interdisciplinary and diversified health education combined with personalized nutrition intervention. The fasting blood-glucose (FPG), two-hour postprandial blood glucose (2hPBG), glycated hemoglobin (HbA1C), SDS, SAS scores, and pregnancy outcome of the two groups of pregnant women were analyzed and compared. RESULTS: The differences in the levels of FBG, 2hPBG and HbA1C between the two groups before nursing were not statistically significant. After nursing, the levels of FBG, 2hPBG, and HbA1C of the two groups of patients decreased, and the differences in each group before and after intervention were statistically significant. These indexes were lower in the research group than in the control group, the differences being statistically significant. There were no significant differences between the two groups in SAS and SDS scores before nursing, but there were statistically significant differences after nursing. The incidence of unfavorable pregnancy outcome was lower in the research group (8.89%) than in the control group (14.44%), but the difference was not statistically significant (p > 0.05). CONCLUSIONS: Interdisciplinary and diversified health education combined with personalized nutrition intervention can effectively reduce FPG, 2hPG, SDS, and SAS scores in GDM women.

5.
Anal Chim Acta ; 1178: 338804, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34482869

RESUMO

Gold nanoparticle (AuNP)-based colorimetric biosensors have been widely used for pH sensing and monitoring its changes. However, few AuNP-based pH sensors have been developed through the manipulation of the aggregation states of AuNPs via i-motif DNA. We herein report i-motif DNA-assisted pH-responsive gold nanoparticle assembly (termed RGA), which shows a reversible and highly sensitive response to pH variation between 6.20 and 7.40. The acidic pH triggers the disassembly of the RGA, thus converting the AuNPs from aggregation state to disperse state, which leads to a color transition from blue-purple to red. Therefore, the pH value can be estimated by naked-eye determination or UV-vis spectroscopy analysis. More significantly, the visually detectable color change is monitored using the built-in camera of a smartphone. The RGB (red, green, blue) values of the RGA solution are measured by a smartphone application (APP). Following data processing, the RGB values can be converted into pH value, providing a new strategy for the on-site and real-time pH sensing. Furthermore, the pH-induced conformation change of i-motif DNA allows the RGA to detect a slight pH fluctuation in the catalytic oxidation of glucose by glucose oxidase and the hydrolysis of urea by urease.


Assuntos
Ouro , Nanopartículas Metálicas , Colorimetria , Concentração de Íons de Hidrogênio , Smartphone
6.
Molecules ; 26(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443603

RESUMO

Abnormal levels of reduced glutathione (GSH) and glutathione reductase (GR) are usually related to a variety of diseases, so it is of great significance to determine the GSH concentration and GR activity. We herein develop a smartphone-assisted colorimetric biosensor for the detection of GSH and GR activity in human serum and mouse liver using hemin/G-quadruplex DNAzyme. Firstly, an obvious color change from colorless to green can be observed, owing to the high peroxidase-like activity of hemin/G-quadruplex DNAzyme toward 2,2'-azino-bis(3-ethylbenzothiozoline-6-sulfonic acid) (ABTS). With the addition of GSH or GR, the H2O2-mediated oxidation of ABTS catalyzed by hemin/G-quadruplex DNAzyme is significantly inhibited, resulting in remarkable color fading. Therefore, the detection of GSH and GR activity can be achieved by observing the color transition or measuring the absorbance at 420 nm. The detection limit was estimated to be as low as 0.1 µM and 10 µU/mL for GSH and GR, respectively. More interestingly, the RGB values of the sensing system can be identified by the smartphone application (APP, color collect), which makes it an ideal format for on-site determination and point-of-care testing (POCT). In addition, the proposed method shows excellent selectivity and acceptable applicability for the determination of GSH concentration and GR activity in human serum samples and mouse liver tissues, which might hold great application potential in clinical diagnosis and drug screening.


Assuntos
Técnicas Biossensoriais/métodos , DNA Catalítico/metabolismo , Glutationa Redutase/sangue , Glutationa/sangue , Hemina/metabolismo , Fígado/metabolismo , Smartphone , Animais , Colorimetria , DNA Catalítico/química , Quadruplex G , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Humanos , Camundongos , Oxirredução
7.
Artigo em Inglês | MEDLINE | ID: mdl-34453540

RESUMO

OBJECTIVE: Polycystic ovary syndrome (PCOS) is a highly heritable disease. Emerging evidence elucidated the elevated prevalence of reproductive abnormalities in first-degree relatives (FDRs) of patients with PCOS. METHODS: Ten databases were searched in December 2020 (PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, CBM, CNKI, VIP and WanFang and WHO international clinical trials registry platform). This study included cohort, case-control, or cross-sectional studies. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement was followed. Dichotomous data from each of the eligible studies were combined by Mantel-Haenszel model. Standard mean differences with 95% confidence intervals were assessed. Heterogeneities were assessed using I  2 statistics, and the quality of evidence was evaluated by AHRQ EPC program and GRADE approach. RESULTS: Thirty-eight studies were included. The prevalence of PCOS (0.22; 95%CI 0.16 to 0.29), menstrual irregularities (0.28; 95%CI 0.22 to 0.34, P<0.01) and ovary morphological changes were elevated in female PCOS FDRs. Female FDRs also presented with increased levels of luteinizing hormone, total testosterone (SMD, 0.53; 95%CI 0.28 to 0.78, P<0.01), unconjugated testosterone, free androgen index, dehydroepiandrosterone sulfate (DHEAS), and anti-Mullerian hormone levels. Subgroup analyses indicated that some of these changes begun in pubertal girls. Furthermore, fathers of PCOS had higher risk of premature baldness. The DHEAS level was elevated in male FDRs. CONCLUSIONS: The findings of this analysis suggested that FDRs of patients with PCOS suffered from reproductive endocrinological dysregulations. Thus, more attention should be focused on this population. (PROSPERO-CRD42020183243).

8.
PLoS One ; 16(8): e0255160, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34358238

RESUMO

OBJECTIVE: Irritable bowel syndrome (IBS) affects children's quality of life and learning. The purpose of this research was to systematically evaluate the efficacy of probiotic adjuvant therapy for IBS in children. METHODS: The Web of Science, PubMed, Cochrane Library, EMBASE and Clinical Trials databases were electronically searched for randomized controlled trials (RCTs) published prior to January 2021 exploring the use of probiotic adjuvant therapy for IBS in children. Strict screening and quality evaluations of the eligible articles were performed independently by 2 researchers. Outcome indexes were extracted, and a meta-analysis of the data was performed using RevMan 5.4.1 and STATA 16 software. Finally, the risk of bias in the included studies was assessed with the RCT bias risk assessment tool recommended in the Cochrane Handbook for Systematic Reviews of Interventions (5.1.0). RESULTS: A total of nine RCTs were included. In children, probiotics significantly reduced the abdominal pain score (I2 = 95%, SMD = -1.15, 95% (-2.05, -0.24), P = 0.01) and Subject's Global Assessment of Relief (SGARC) score (I2 = 95%, MD = -3.84, 95% (-6.49, -1.20), P = 0.004), increased the rate of abdominal pain treatment success (I2 = 0%, RR = 3.44, 95% (1.73, 6.87), P = 0.0005) and abdominal pain relief (I2 = 40%, RR = 1.48, 95% (0.96, 2.28), P = 0.08), and reduced the frequency of abdominal pain (I2 = 2%, MD = -0.82, 95% (-1.57, -0.07), P = 0.03). However, we found that it might not be possible to relieve abdominal pain by increasing the daily intake of probiotics. CONCLUSIONS: Probiotics are effective at treating abdominal pain caused by IBS in children, however, there was no significant correlation between abdominal pain and the amount of probiotics ingested. More attention should be given to IBS in children, and a standardized evaluation should be adopted.

9.
Chem Biol Interact ; 345: 109566, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34174250

RESUMO

Mammalian carboxylesterases (CES), the key members of the serine hydrolase superfamily, hydrolyze a wide range of endogenous substances and xenobiotics bearing ester or amide bond(s). In humans, most of identified CES are segregated into the CES1A and CES2A subfamilies. Strong inhibition on human CES (including hCES1A and hCES2A) may modulate pharmacokinetic profiles of CES-substrate drugs, thereby changing the pharmacological and toxicological responses of these drugs. This review covered recent advances in discovery of hCES inhibitors from clinically available medications, as well as their impact on CES-associated drug metabolism. Three comprehensive lists of hCES inhibitors deriving from clinically available medications including therapeutic drugs, pharmaceutical excipients and herbal medicines, alongside with their inhibition potentials and inhibition parameters, are summarized. Furthermore, the potential risks of hCES inhibitors to trigger drug/herb-drug interactions (DDIs/HDIs) and future concerns in this field are highlighted. Potent hCES inhibitors may trigger clinically relevant DDIs/HDIs, especially when these inhibitors are co-administrated with CES substrate-drugs with very narrow therapeutic windows. All data and knowledge presented here provide key information for the clinicians to assess the risks of clinically available hCES inhibitors on drug metabolism. In future, more practical and highly specific substrates for hCES1A/hCES2A should be developed and used for studies on CES-mediated DDIs/HDIs both in vitro and in vivo.


Assuntos
Carboxilesterase/antagonistas & inibidores , Carboxilesterase/metabolismo , Inibidores Enzimáticos/farmacologia , Preparações Farmacêuticas/metabolismo , Animais , Descoberta de Drogas , Humanos , Inativação Metabólica/efeitos dos fármacos
10.
Biomaterials ; 275: 120984, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34186235

RESUMO

Critical size bone defects are frequently caused by accidental trauma, oncologic surgery, and infection. Distraction osteogenesis (DO) is a useful technique to promote the repair of critical size bone defects. However, DO is usually a lengthy treatment, therefore accompanied with increased risks of complications such as infections and delayed union. Here, we demonstrated that magnesium (Mg) nail implantation into the marrow cavity degraded gradually accompanied with about 4-fold increase of new bone formation and over 5-fold of new vessel formation as compared with DO alone group in the 5 mm femoral segmental defect rat model at 2 weeks after distraction. Mg nail upregulated the expression of calcitonin gene-related peptide (CGRP) in the new bone as compared with the DO alone group. We further revealed that blockade of the sensory nerve by overdose capsaicin blunted Mg nail enhanced critical size bone defect repair during the DO process. CGRP concentration-dependently promoted endothelial cell migration and tube formation. Meanwhile, CGRP promoted the phosphorylation of focal adhesion kinase (FAK) at Y397 site and elevated the expression of vascular endothelial growth factor A (VEGFA). Moreover, inhibitor/antagonist of CGRP receptor, FAK, and VEGF receptor blocked the Mg nail stimulated vessel and bone formation. We revealed, for the first time, a CGRP-FAK-VEGF signaling axis linking sensory nerve and endothelial cells, which may be the main mechanism underlying Mg-enhanced critical size bone defect repair when combined with DO, suggesting a great potential of Mg implants in reducing DO treatment time for clinical applications.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina , Osteogênese por Distração , Animais , Regeneração Óssea , Calcitonina , Células Endoteliais , Proteína-Tirosina Quinases de Adesão Focal , Magnésio , Osteogênese , Ratos , Fator A de Crescimento do Endotélio Vascular
11.
Acta Pharmacol Sin ; 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34183756

RESUMO

Jingyin granules, a marketed antiviral herbal medicine, have been recommended for treating H1N1 influenza A virus infection and Coronavirus disease 2019 (COVID-19) in China. To fight viral diseases in a more efficient way, Jingyin granules are frequently co-administered in clinical settings with a variety of therapeutic agents, including antiviral drugs, anti-inflammatory drugs, and other Western medicines. However, it is unclear whether Jingyin granules modulate the pharmacokinetics of Western drugs or trigger clinically significant herb-drug interactions. This study aims to assess the inhibitory potency of the herbal extract of Jingyin granules (HEJG) against human drug-metabolizing enzymes and to clarify whether HEJG can modulate the pharmacokinetic profiles of Western drug(s) in vivo. The results clearly demonstrated that HEJG dose-dependently inhibited human CES1A, CES2A, CYPs1A, 2A6, 2C8, 2C9, 2D6, and 2E1; this herbal medicine also time- and NADPH-dependently inhibited human CYP2C19 and CYP3A. In vivo tests showed that HEJG significantly increased the plasma exposure of lopinavir (a CYP3A-substrate drug) by 2.43-fold and strongly prolonged its half-life by 1.91-fold when HEJG (3 g/kg) was co-administered with lopinavir to rats. Further investigation revealed licochalcone A, licochalcone B, licochalcone C and echinatin in Radix Glycyrrhizae, as well as quercetin and kaempferol in Folium Llicis Purpureae, to be time-dependent CYP3A inhibitors. Collectively, our findings reveal that HEJG modulates the pharmacokinetics of CYP substrate-drug(s) by inactivating CYP3A, providing key information for both clinicians and patients to use herb-drug combinations for antiviral therapy in a scientific and reasonable way.

12.
Pestic Biochem Physiol ; 176: 104860, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34119211

RESUMO

The Asian gypsy moth, Lymantria dispar, as one of the most important forest pests in the world, can feed on more than 500 species of host plants, causing serious damage to the forests. Poplar is one of the favorite host plants of L. dispar. The present study aimed to explore the effects of poplar secondary metabolites on the growth and detoxification function of L. dispar larvae. We also aimed to study the expression of glutathione S-transferase (GST) genes in different developmental stages and in response to treatment with secondary metabolites. Six kinds of main secondary metabolites and three groups of characteristic mixed secondary metabolites were selected as follows: Caffeic acid, salicin, rutin, quercetin, catechol, flavone, mixture 1 (salicin and flavone), mixture 2 (salicin, caffeic acid and catechol), and mixture 3 (flavone, caffeic acid and catechol) according to the content changes of secondary metabolites in poplar. The thirteen GST genes were selected as candidate genes to study the expression of GST genes in different developmental stages and after treatment with secondary metabolites using quantitative real-time reverse transcription PCR. The LdGSTe4 and LdGSTo1 genes could be induced by secondary metabolites and were screened to explore their detoxification function against secondary metabolites using RNA interference technology. The results showed that salicin and rutin significantly induced the expression of LdGSTe4 and LdGSTo1. Under the stress of secondary metabolites, LdGSTe4 silencing affected the adaptability of L. dispar larvae to salicin and rutin. LdGSTe4 silencing resulted in a significant decrease in the body weight of L. dispar, but had little effect on the relative growth rate, relative consumption rate, efficiency of conversion of ingested food, efficiency of conversion of digested food, and approximate digestibility, as well as the survival rate and development time. These results provide a deeper understanding of the adaptive mechanism of L. dispar to host plants, form the foundation for the further research into the host resistance mechanism, and identify target genes for breeding resistant transgenic poplar.


Assuntos
Glutationa Transferase/genética , Proteínas de Insetos/genética , Mariposas , Populus , Animais , Larva/enzimologia , Larva/genética , Mariposas/enzimologia , Mariposas/genética , Populus/metabolismo , Quercetina
13.
Bioorg Med Chem ; 40: 116187, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33965840

RESUMO

Carboxylesterase 2 (CES2) is one of the most important Phase I drug metabolizing enzymes in the carboxylesterase family. It plays crucial roles in the bioavailability of oral ester prodrugs and the therapeutic effect of some anticancer drugs such as irinotecan (CPT11) and capecitabine. In addition to the well-known roles of CES2 in xenobiotic metabolism, the enzyme also participates in endogenous metabolism and the production of lipids. In this study, we synthesized a series of pyrazolones and assayed their inhibitory effects against CES2 in vitro. Structure-activity relationship analysis of these pyrazolones reveals that the introduction of 4-methylphenyl unit (R1), 4-methylbenzyl (R2) and cyclohexyl (R3) moieties are beneficial for CES2 inhibition. Guided by these SARs results, 1-cyclohexyl-4-(4-methylbenzyl)-3-p-tolyl-1H- pyrazol-5(4H)-one (27) was designed and synthesized. Further investigations demonstrated that the compound 27 exhibited stronger CES2 inhibition activity with a lower IC50 value (0.13 µM). The inhibition kinetic study demonstrated that compound 27 inhibited the hydrolysis of CES2-fluorescein diacetate (FD) through non-competitive inhibition. In addition, the molecular docking showed that the core of pyrazolone, the cyclohexane moiety, 4-methylbenzyl and 4-methylphenyl groups in compound 27 all played important roles with the amino acid residues of CSE2. Also, compound 27 could inhibit adipocyte adipogenesis induced by mouse preadipocytes. In brief, we designed and synthesized a novel pyrazolone compound with a strong inhibitory ability on CES2 and could inhibit the adipogenesis induced by mouse preadipocytes, which can be served as a promising lead compound for the development of more potent pyrazolone-type CES2 inhibitors, and also used as a potential tool for exploring the biological functions of CES2 in human being.

14.
Elife ; 102021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-34018922

RESUMO

Neurofibrillary tangles composed of hyperphosphorylated tau and synaptic dysfunction are characteristics of Alzheimer's disease (AD). However, the underlying molecular mechanisms remain poorly understood. Here, we identified Amphiphysin I mediates both tau phosphorylation and synaptic dysfunction in AD. Amphiphysin I is cleaved by a cysteine proteinase asparagine endopeptidase (AEP) at N278 in the brains of AD patients. The amount of AEP-generated N-terminal fragment of Amphiphysin I (1-278) is increased with aging. Amphiphysin I (1-278) inhibits clathrin-mediated endocytosis and induces synaptic dysfunction. Furthermore, Amphiphysin I (1-278) binds p35 and promotes its transition to p25, thus activates CDK5 and enhances tau hyperphosphorylation. Overexpression of Amphiphysin I (1-278) in the hippocampus of Tau P301S mice induces synaptic dysfunction, tau hyperphosphorylation, and cognitive deficits. However, overexpression of the N278A mutant Amphiphysin I, which resists the AEP-mediated cleavage, alleviates the pathological and behavioral defects. These findings suggest a mechanism of tau hyperphosphorylation and synaptic dysfunction in AD.

15.
Anal Methods ; 13(24): 2671-2678, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34036983

RESUMO

Dipeptidyl peptidase-IV (DPP-IV) plays a critical role in glucose metabolism and has become an important target for type 2 diabetes mellitus. We previously reported a two-photon fluorescent probe glycyl-prolyl-N-butyl-4-amino-1,8-naphthalimide (GP-BAN) for DPP-IV detection with high specificity and sensitivity. In this study, a high-throughput screening (HTS) method for DPP-IV inhibitors using human plasma as the enzyme source was established and optimized. Further investigations demonstrate that the IC50 value of sitagliptin (listed as the DPP-IV inhibitor) determined with human recombinant DPP-IV (36.22 nM) is very similar to that in human plasma (39.18 nM), and sitagliptin acts as a competitive inhibitor against human plasma DPP-IV-mediated GP-BAN hydrolysis. These results indicate that expensive human recombinant DPP-IV can be replaced by human plasma in this GP-BAN-based assay. On this basis, GP-AMC (commercial probe) was used as a comparison to verify this method, and the catalytic efficacy (Vmax/Km) for GP-AMC (0.09 min-1) hydrolysis in human plasma is lower than that for GP-BAN (0.21 min-1). Further analysis of inhibition kinetics (sitagliptin) and molecular docking (GP-BAN and GP-AMC) showed that GP-BAN has better specificity and affinity for enzymes than GP-AMC. Finally, the optimized method was used for the HTS of DPP-IV inhibitors in 69 natural alkaloids.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Diabetes Mellitus Tipo 2/tratamento farmacológico , Ensaios de Triagem em Larga Escala , Humanos , Simulação de Acoplamento Molecular , Fosfato de Sitagliptina
16.
J Enzyme Inhib Med Chem ; 36(1): 1079-1087, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34030574

RESUMO

Inhibitors of COMT are clinically used for the treatment of Parkinson's disease. Here, we report the first natural pentacyclic triterpenoid-type COMT inhibitors and their structure-activity relationships and inhibition mechanism. The most potent compounds were found to be oleanic acid, betulinic acid and celastrol with IC50 values of 3.89-5.07 µM, that acted as mixed (uncompetitive plus non-competitive) inhibitors of COMT, representing a new skeleton of COMT inhibitor. Molecular docking suggested that they can specifically recognise and bind with the unique hydrophobic residues surrounding the catechol pocket. Furthermore, oleanic acid and betulinic acid proved to be less disruptive of mitochondrial membrane potential (MMP) compared to tolcapone, thus reducing the risk of liver toxicity. These findings could be used to produce an ideal lead compound and to guide synthetic efforts in generating related derivatives for further preclinical testing.


Assuntos
Produtos Biológicos/farmacologia , Catecol O-Metiltransferase/metabolismo , Inibidores Enzimáticos/farmacologia , Triterpenos Pentacíclicos/farmacologia , Produtos Biológicos/síntese química , Produtos Biológicos/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Cinética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Conformação Molecular , Simulação de Acoplamento Molecular , Triterpenos Pentacíclicos/síntese química , Triterpenos Pentacíclicos/química , Proteínas Recombinantes/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade
17.
Placenta ; 109: 64-71, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33990028

RESUMO

INTRODUCTION: Pre-eclampsia is characterized by insufficient spiral artery remodeling, and trophoblast dysfunction plays an important role in this process. Noncoding RNAs (microRNAs (miRNAs) and long noncoding RNAs (LncRNAs) are included) can regulate trophoblasts. MicroRNA-210 (miR-210) can decrease trophoblast cell migration and invasion and may act as a biomarker for preeclampsia. LncRNA maternally expressed gene 3 (MEG3) plays a positive role in pre-eclampsia, and MEG3 can be a downstream target of miR-210 in human umbilical vein endothelial cells (HUVEC). However, the effect of miR-210 on MEG3 and the mechanism of action of the miR-210/MEG3 axis in trophoblasts remain unclear. METHOD: The localization of miR-210 and MEG3 in the human placenta in early pregnancy was determined by in situ hybridization. Then, HTR8/SVneo cells were used to investigated the effect of miR-210 on MEG3 expression and biological activity of trophoblasts in the migration and invasion assays. Gain- and loss-of-function experiments were performed to determine the mechanism of action of miR-210 and MEG3 in Epithelial-mesenchymal transition (EMT) of HTR8/SVneo cells. RESULTS: The qRT-PCR and western blotting results demonstrated that the upregulation of miR-210 decreases MEG3, N-cadherin and Vimentin expression and increases E-cadherin expression to inhibit EMT in HTR-8/SVneo cells. Inhibition of the expression of miR-210 results in the opposite effects. Gain- and loss-of-function assay indicated that miR-210 can impair the EMT, migration, and invasion of HTR8/SVneo cells by regulating the expression of MEG3. DISSCUSSION: MiR-210 may be a negative regulator of trophoblast EMT that acts by suppressing MEG3 expression.

18.
Zhongguo Zhong Yao Za Zhi ; 46(10): 2527-2536, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34047100

RESUMO

A comprehensive analytical method based on ultra-fast liquid chromatography coupled with triple quadrupole/linear ion trap tandem mass spectrometry(UFLC-QTRAP-MS/MS) was established for simultaneous determination of the content of 38 active components in Abelmoschi Corolla, including flavonoids, organic acids, nucleosides and amino acids, so as to investigate the effects of different harvesting and processing methods on multi-active components in Abelmoschi Corolla. The chromatographic separation was performed on a XBridg®C_(18) column(4.6 mm×100 mm, 3.5 µm) with(0.1% formic acid water) methanol-acetonitrile(1∶1) as the mobile phase for gradient elution at 30 ℃. The flow rate was 0.5 mL·min~(-1). The components were detected in a multiple-reaction monitoring(MRM) mode. The gray relational analysis(GRA) was used to comprehensively evaluate the multiple active components of Abelmoschi Corolla at different harvesting times and drying temperatures. The results showed that 38 components had a good linearity with correlation coefficients all above 0.999 0. The method featured a good precision, repeatability and stability with the relative stan-dard deviations(RSDs) of less than 5.0%. Recoveries ranged from 98.06% to 104.4% with RSD between 0.22% and 4.9%. The results of GRA indicated that a better quality in the samples collected on September 9 th. Samples dried at 90 ℃ had a better quality. The established method is accurate and reliable, and can be used to assess the internal quality of Abelmoschi Corolla. This study can provide basic materials for determining appropriate harvesting time and processing method of Abelmoschi Corolla.


Assuntos
Nucleosídeos , Espectrometria de Massas em Tandem , Aminoácidos , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida
19.
Prog Neurobiol ; 203: 102074, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33992672

RESUMO

Neurite deficits and synaptic dysfunction contribute to cognitive impairments in Alzheimer's disease (AD). However, the underlying molecular mechanisms remain unclear. Here, we show that γ-adducin, a cytoskeleton-associated protein that assembles the spectrin-actin framework, is cleaved by a lysosomal cysteine proteinase named asparagine endopeptidase (AEP). AEP is upregulated and activated during aging and cleaves γ-adducin at N357, disrupting spectrin-actin assembly. Moreover, γ-adducin (1-357) fragment downregulates the expression of Rac2, leading to defects in neurite outgrowth. Expression of the γ-adducin (1-357) fragment in the hippocampus of tau P301S transgenic mice resulted in significant AD-like pathology and cognitive deficits. In summary, AEP-mediated fragmentation of γ-adducin plays a vital role in AD. Blocking the activity of AEP might be a novel therapeutic target for AD.

20.
Cancer Lett ; 514: 90-102, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34023418

RESUMO

Effective treatment regimens for triple-negative breast cancer (TNBC) are relatively scarce due to a lack of specific therapeutic targets. Epidermal growth factor receptor (EGFR) signaling is highly active in TNBC and is associated with poor prognosis. Most EGFR antagonists, which significantly improve outcome in lung and colon cancer, have shown limited clinical effects in breast cancer. However, limiting EGFR expression in TNBC is a potential strategy for improving the clinical efficacy of EGFR antagonists. Here, we found that the gamma-aminobutyric acid type A receptor π subunit (GABRP), as a membrane protein enriched in TNBC stem cells, interacted with EGFR and significantly sustained its expression, resulting in stemness maintenance and chemotherapy resistance. Silencing GABRP induced down-regulation of EGFR signaling, which hindered cell stemness and enhanced sensitivity to chemotherapies, including paclitaxel, doxorubicin, and cisplatin. We also identified that retigabine, an FDA-approved drug for adjunctive treatment of seizures, increased the sensitivity of EGFR to gefitinib in gefitinib-resistant cells. Our findings show that GABRP can sustain the stemness of TNBC via modulating EGFR expression, suggesting that GABRP may be a potential therapeutic target that can address EGFR inhibitor resistance in TNBC.

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