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1.
Dig Dis Sci ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967903

RESUMO

INTRODUCTION: Scissor-type knives are spreading as safe devises in endoscopic submucosal dissection (ESD). We evaluated the efficacy of two kinds of scissor-type knives (Clutch Cutter: CC, Fujifilm Co. and SB Knife Jr2: SB, SB-KAWASUMI Laboratories. Inc.) in colorectal ESD. METHODS: This single-center retrospective study analyzed 178 ESD cases treated with CC from January 2020 to August 2021 and 91 cases with SB from September 2021 to December 2023. The two groups were compared through propensity score matching. Therapeutic results, such as ESD procedure time, en bloc resection rate, perioperative bleeding frequency, and complications, were analyzed in each group. Risk factors for long ESD procedure time (≥ 90 min) were also examined. RESULTS: After matching, 87 cases in each group were analyzed. There was no significant difference in the ESD procedure time (min, median [interquartile range]) between the CC and SB groups (54.0 [36.0-72.0] vs. 53.0 [39.0-72.0], p = 0.99). Additionally, there were no differences in the en bloc resection (100% vs. 100%, p = 1.00), perioperative perforation (1.1% vs. 1.1%, p = 1.00), or delayed bleeding (1.1% vs. 0.0%, p = 1.00). There was a significant difference in perioperative bleeding frequency (mean ± standard deviation: 1.8 ± 2.6 vs. 3.0 ± 3.5, p < 0.01). The significant risk factors (odds ratio [95% confidence interval]) for long ESD procedure time in patients treated with CC or SB were antiplatelet (7.51 [1.82-31.00]), large lesion size (1.08 [1.05-1.12]), severe fibrosis (24.30 [7.60-77.90]), and perioperative bleeding frequency (1.34 [1.14-1.56]). CONCLUSIONS: CC and SB in colorectal ESD enabled high en bloc resection and low complication rates. CC showed significantly less perioperative bleeding than SB.

2.
Eur J Med Chem ; 275: 116565, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38878518

RESUMO

Transient receptor potential canonical 5 (TRPC5) is a calcium-permeable non-selective cation channel involved in various pathophysiological processes, including renal injury. Recently, GFB-887, an investigational pyridazinone TRPC5 inhibitor, demonstrated significant therapeutic potential in a Phase II clinical trial for focal segmental glomerulosclerosis (FSGS), a rare and severe form of chronic kidney disease (CKD). In the current study, based on the structure of GFB-887, we conducted extensive structural modification to explore novel TRPC5 inhibitors with desirable drug-like properties and robust nephroprotective efficacy. A series of pyridazinone derivatives featuring a novel tetrahydroimidazo[1,2-a]pyrazine scaffold were synthesized and their activities were evaluated in HEK-293 cells stably expressing TRPC5 using a fluorescence-based Ca2+ mobilization assay. Among these compounds, compound 12 is turned out to be a potent TRPC5 inhibitor with apparent affinity comparable to the parent compound GBF-887. Compound 12 is highly selective on TRPC4/5 over TRPC3/6/7 and hERG channels, along with acceptable pharmacokinetic properties and a favorable safety profile. More importantly, in a rat model of hypertension-induced renal injury, oral administration of compound 12 (10 mg/kg, BID) efficaciously reduced mean blood pressure, inhibited proteinuria, and protected podocyte damage. These findings further confirmed the potential of TRPC5 inhibitors on the CKD treatment and provided compound 12 to be a valuable tool for exploring TRPC4/5 pathophysiology.


Assuntos
Hipertensão , Pirazinas , Canais de Cátion TRPC , Animais , Humanos , Ratos , Pirazinas/química , Pirazinas/farmacologia , Pirazinas/síntese química , Canais de Cátion TRPC/antagonistas & inibidores , Canais de Cátion TRPC/metabolismo , Células HEK293 , Relação Estrutura-Atividade , Masculino , Hipertensão/tratamento farmacológico , Descoberta de Drogas , Estrutura Molecular , Piridazinas/farmacologia , Piridazinas/química , Piridazinas/síntese química , Relação Dose-Resposta a Droga , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/química , Anti-Hipertensivos/síntese química , Ratos Sprague-Dawley , Imidazóis/química , Imidazóis/farmacologia , Imidazóis/síntese química
3.
J Colloid Interface Sci ; 673: 434-443, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38878377

RESUMO

Electro-Fenton is an effective process for degrading hard-to-degrade organic pollutants, such as tetracycline (TC). However, the degradation efficiency of this process is limited by the activity and stability of the cathode catalyst. Herein, a temperature gradient pyrolysis strategy and oxidation treatment is proposed to modulate the coordination environment to prepare oxygen-doped cobalt monoatomic electrocatalysts (CoNOC). The CoNOC catalysts can achieve the selectivity of 93 % for H2O2 with an electron transfer number close to 2. In the H-cell, the prepared electrocatalysts can achieve more than 100 h of H2O2 production with good stability and the yield of 1.41 mol gcatalyst-1 h-1 with an average Faraday efficiency (FE) of more than 88 %. The calculations indicate that the epoxy groups play a crucial role in modulating the oxygen reduction pathway. The O doping and unique N coordination of Co single-atom active sites (CoN(Pd)3N(Po)1O1) can effectively weaken the O2/OOH* interaction, thereby promoting the production of H2O2. Finally, the electro-Fenton system could achieve a TC degradation rate of 94.9 % for 120 min with a mineralization efficiency of 87.8 % for 180 min, which provides a reliable option for antibiotic treatment. The significant involvement of OH in the electro-Fenton process was confirmed, and the plausible mineralization pathway for TC was proposed.

4.
J Colloid Interface Sci ; 673: 486-495, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38879990

RESUMO

Dual-atoms catalysts (DACs), while inheriting the advantages of maximum atom utilization ratio and excellent selectivity of single-atom catalysts (SACs), can better enhance the catalytic activity through the synergy of adjacent atoms. Therefore, DACs are considered to be very potential catalysts for CO2 to CO conversion. Its catalytic activity is greatly influenced by the coordination environment and morphology. Here, hollow urchin-like NiNC catalysts (Ni-NC(HU)-x, x = 100, 50, 25, 0) were synthesized using urchin-like nickel particles as template. By adjusting the amount of additional nitrogen source, the percentage content of pyridinic-N was adjusted as well as further affecting the coordination environment. Among them, Ni-NC(HU)-50, which had the highest content of pyridinic-N, formed a dual-atoms coordination structure and had the best catalytic performance that the CO Faradaic efficiency (FECO) reached 97.2 % at -0.9 V vs. reversible hydrogen electrode (RHE) and sustained above 95 % within 50 h. In-situ attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) and density functional theory (DFT) calculations showed that Ni-NC(HU)-50 exhibited the best performance of CO2 reduction reaction (CO2RR) by lowering the *COOH formation free energy barrier and its favorable dual desorption mechanism of *COL and *COB.

5.
Bioorg Med Chem ; 107: 117761, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38795571

RESUMO

Small-molecule glucagon-like peptide-1 receptor (GLP-1R) agonists are recognized as promising therapeutics for type 2 diabetes mellitus (T2DM) and obesity. Danuglipron, an investigational small-molecule agonist, has demonstrated high efficacy in clinical trials. However, further development of danuglipron is challenged by a high rate of gastrointestinal adverse events. While these effects may be target-related, it is plausible that the carboxylic acid group present in danuglipron may also play a role in these outcomes by affecting the pharmacokinetic properties and dosing regimen of danuglipron, as well as by exerting direct gastrointestinal irritation. Therefore, this study aims to replace the problematic carboxylic acid group by exploring the internal binding cavity of danuglipron bound to GLP-1R using a water molecule displacement strategy. A series of novel triazole-containing compounds have been designed and synthesized during the structure-activity relationship (SAR) study. These efforts resulted in the discovery of compound 2j with high potency (EC50 = 0.065 nM). Moreover, docking simulations revealed that compound 2j directly interacts with the residue Glu387 within the internal cavity of GLP-1R, effectively displacing the structural water previously bound to Glu387. Subsequent in vitro and in vivo experiments demonstrated that compound 2j had comparable efficacy to danuglipron in enhancing insulin secretion and improving glycemic control. Collectively, this study offers a practicable approach for the discovery of novel small-molecule GLP-1R agonists based on danuglipron, and compound 2j may serve as a lead compound to further exploit the unoccupied internal cavity of danuglipron's binding pocket.


Assuntos
Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon , Animais , Humanos , Masculino , Camundongos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Relação Dose-Resposta a Droga , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon/química , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon/farmacologia , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/síntese química , Simulação de Acoplamento Molecular , Estrutura Molecular , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/síntese química , Relação Estrutura-Atividade , Triazóis/química , Triazóis/farmacologia , Triazóis/síntese química
6.
Small ; 20(26): e2309819, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38229574

RESUMO

The unique properties of high entropy alloy (HEA) catalysts, particularly their severe lattice distortion and the synergistic effect of multiple components, endow them with exceptional multifunctional catalytic performance. Herein, it is revealed for the first time, that the ultrasmall PtRhNiFeCu HEA nanoparticles catalyst shows outstanding catalytic activity for both hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR). The catalyst exhibits an impressively low overpotential of 13 mV at 10 mA cm-2, a Tafel slope of 29.6 mV dec-1, and high mass activity of 7.6 A mgPt -1 at -50 mV in alkaline media, and long-term stability of at least 20 h. Moreover, the catalyst also demonstrates effective catalytic activity for acidic ORR with a commendable performance of 1.23 A mgPt -1, much exceeding the commercial Pt/C catalyst. Density functional theory (DFT) calculations unveil that the efficient electrocatalytic performance for HER and ORR can be primarily attributed to the synergistic effect between components tailors and optimizes the electronic structure of PtRhNiFeCu/C HEA, which not only enhances the HER activity through increasing water capture capability, decreasing energetic barrier for water dissociation, and optimizing hydrogen absorption but also initiates non-platinum active sites with high ORR activity, achieving the improved ORR performance.

7.
Eur J Med Chem ; 264: 116017, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38070432

RESUMO

The shortage of cholesterol gallstones treatment intensifies the need to discover of effective small molecule drugs. Clinical follow-up and studies have found that activation of somatostatin receptor subtype 5 (SSTR5) reduce gallbladder contraction and thus increase the risk of cholesterol gallstones, implying that antagonizing SSTR5 may promote gallbladder emptying and reduce the formation of gallstones. Herein, we discovered novel SSTR5 antagonists and firstly investigated its effects on cholesterol gallstone. From loperamide, a reported seed structure with micromole activity, we identified optimal compound 23 as an SSTR5 antagonist exhibiting single-digit nanomolar potency, low hERG inhibition and oral availability. Further in vivo evaluation revealed that 23 significantly promoted gallbladder emptying. Moreover, in a mouse cholesterol gallstone model, 23 (3 mg/kg) effectively reduced the cholesterol gallstones formation, showing better efficacy than the clinical first-line drug UDCA (60 mg/kg), providing a new insight into the development of anti-gallstone drugs.


Assuntos
Cálculos Biliares , Animais , Camundongos , Cálculos Biliares/tratamento farmacológico , Receptores de Somatostatina , Colesterol
8.
J Arthroplasty ; 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38122838

RESUMO

BACKGROUND: In the current shift toward value-based healthcare, patient-reported outcome measures (PROMs) have become essential to assess the effectiveness of medical interventions. However, elucidation of the optimal timeframe for PROMs evaluation remains crucial. This study aimed to (1) determine the proportion of patients who experienced clinically meaningful improvements in PROMs scores at each follow-up visit after total hip arthroplasty (THA) and total knee arthroplasty (TKA) and (2) calculate and apply the clinical relevance ratio (CRR) for these long-term PROM collections postoperatively. METHODS: A total of 12 independent studies reporting THA (n = 8 studies) and TKA (n = 4 studies) postoperative PROM data with up to 10 years of follow-up in Europe or the United States were aggregated. A distribution-based minimal clinically important difference threshold and CRR were used to determine which patients had clinically meaningful improvements in PROMs at 1, 5, and 10 years. RESULTS: The proportion of patients who had clinically meaningful improvements in PROM scores stabilized after 1 year following both THA and TKA. Overall, the CRR decreased over time for all PROMs, with the CRR beginning to decrease at 1-year follow-up, bringing into question the robustness and clinical relevance of long-term PROMs data. CONCLUSIONS: The present study challenges the utility of requiring PROMs with a minimum follow-up of 2 years for THA and TKA. Research efforts should be focused on registries evaluating implant survivorship at longer-term follow-up, while PROMs should be better assessed up to 1-year follow-up. Reconsidering the long-term PROMs assessment would lead to more efficient and cost-effective research in orthopedic outcomes, without compromising data quality.

9.
Bioorg Med Chem ; 96: 117511, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37976806

RESUMO

The G protein-coupled receptor 35 (GPR35) has been identified as a potential target in the treatment of inflammatory bowel disease (IBD). However, the lack of high and equipotent agonists on both human and mouse GPR35 has limited the in vivo study of GPR35 agonists in mouse models of IBD. In this study, structural modifications to lodoxamide provides a series of high and equivalent agonists on human, mouse, and rat GPR35. These molecules eliminate the species selectivity of human to mouse and rat orthologs that have been prevalent with GPR35 agonists including lodoxamide. The cLogP properties are also optimized to make the compounds more obedient to drug-like rules, yielding compound 4b (cLogP = 2.41), which activates human, mouse or rat GPR35 with EC50 values of 76.0, 63.7 and 77.8 nM, respectively. Oral administration of compound 4b at 20 mg/kg alleviates clinical symptoms of DSS-induced IBD in mice, and is slightly more effective than 5-ASA at 200 mg/kg. In summary, it can serve as a new start point for exploiting more potent GPR35 agonists without species differences for the treatment of IBD, and warrants further study.


Assuntos
Doenças Inflamatórias Intestinais , Receptores Acoplados a Proteínas G , Ratos , Camundongos , Humanos , Animais , Receptores Acoplados a Proteínas G/agonistas , Ácido Oxâmico/farmacologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Administração Oral
10.
Sci Bull (Beijing) ; 68(19): 2190-2199, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37580202

RESUMO

Electrocatalytic conversion of biomass-derived 5-hydroxymethylfurfural (HMF) to 2,5-bis(hydroxymethyl)furan (BHMF) presents a compelling strategy for the production of premium chemicals via the utilization of renewable energy sources. Exploring efficient catalytic systems to obtain highly selective BHMF has remained a giant challenge. A design strategy is proposed here to regulate active hydrogen (Hads) production in rhodium (Rh) nanoparticles grown on Cu nanowires (RhCu NWs) catalyst, which achieves a faradaic efficiency (FE) of 92.6% in the electrocatalytic reduction of HMF to BHMF at -20 mA cm-2 with no degradation in performance after 8 cycles. Kinetic investigations and electron spin resonance (ESR) spectroscopy reveal that the incorporation of Rh accelerates the water dissociation and facilitates the generation of Hads. In situ attenuated total reflection surface enhanced infrared absorption spectroscopy (ATR-SEIRAS) further demonstrates that the Rh component boosts the proportion of ordered weakly hydrogen-bonded water molecules on the catalyst surface, which is much easier to dissociate. The construction of an interfacial Hads-rich environment promotes the HMF intermediates binding with Hads to BMHF, thereby suppressing the formation of undesired dimers. This work demonstrates the promise of altering the interfacial water environment as a strategy to boost the electrosynthetic properties of biomass-derived products toward value-added outcomes.

11.
Artigo em Inglês | MEDLINE | ID: mdl-37402193

RESUMO

This brief investigates the stability of neural networks with time-varying delays. Novel stability conditions are derived by employing free-matrix-based inequality and introducing the variable-augmented-based free-weighting matrices in the estimation of the derivative of the Lyapunov-Krasovskii functionals (LKFs). Both techniques avoid the appearance of the nonlinear terms of the time-varying delay. Especially, the time-varying free-weighting matrices associated with the derivative of the delay and the time-varying S-Procedure related to the delay and its derivative are combined to improve the presented criteria. Finally, numerical examples are given to illustrate the benefits of the presented methods.

12.
Nature ; 621(7979): 635-641, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37524305

RESUMO

Class B G-protein-coupled receptors (GPCRs), including glucagon-like peptide 1 receptor (GLP1R) and parathyroid hormone 1 receptor (PTH1R), are important drug targets1-5. Injectable peptide drugs targeting these receptors have been developed, but orally available small-molecule drugs remain under development6,7. Here we report the high-resolution structure of human PTH1R in complex with the stimulatory G protein (Gs) and a small-molecule agonist, PCO371, which reveals an unexpected binding mode of PCO371 at the cytoplasmic interface of PTH1R with Gs. The PCO371-binding site is totally different from all binding sites previously reported for small molecules or peptide ligands in GPCRs. The residues that make up the PCO371-binding pocket are conserved in class B GPCRs, and a single alteration in PTH2R and two residue alterations in GLP1R convert these receptors to respond to PCO371. Functional assays reveal that PCO371 is a G-protein-biased agonist that is defective in promoting PTH1R-mediated arrestin signalling. Together, these results uncover a distinct binding site for designing small-molecule agonists for PTH1R and possibly other members of the class B GPCRs and define a receptor conformation that is specific only for G-protein activation but not arrestin signalling. These insights should facilitate the design of distinct types of class B GPCR small-molecule agonist for various therapeutic indications.


Assuntos
Imidazolidinas , Receptores Acoplados a Proteínas G , Compostos de Espiro , Humanos , Arrestina/metabolismo , Sítios de Ligação , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Imidazolidinas/farmacologia , Ligantes , Peptídeos/farmacologia , Conformação Proteica , Receptor Tipo 1 de Hormônio Paratireóideo/agonistas , Receptor Tipo 1 de Hormônio Paratireóideo/classificação , Receptor Tipo 1 de Hormônio Paratireóideo/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/classificação , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/efeitos dos fármacos , Compostos de Espiro/farmacologia , Desenho de Fármacos
13.
Angew Chem Int Ed Engl ; 62(33): e202307848, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37378584

RESUMO

The site isolation strategy has been employed in thermal catalytic acetylene semihydrogenation to inhibit overhydrogenation and C-C coupling. However, there is a dearth of analogous investigations in electrocatalytic systems. In this work, density functional theory (DFT) simulations demonstrate that isolated Cu metal sites have higher energy barriers on overhydrogenation and C-C coupling. Following this result, we develop Cu single-atom catalysts highly dispersed on nitrogen-doped carbon matrix, which exhibit high ethylene selectivity (>80 % Faradaic efficiency for ethylene, <1 % Faradaic efficiency for C4 , and no ethane) at high concentrations of acetylene. The superior performance observed in the electrocatalytic selective hydrogenation of acetylene can be attributed to the weak adsorption of ethylene intermediates and highly energy barriers on C-C coupling at isolated sites, as confirmed by both DFT calculations and experimental results. This study provides a comprehensive understanding of the isolated sites inhibiting the side reactions of electrocatalytic acetylene semihydrogenation.

14.
J Med Chem ; 66(12): 7988-8010, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37286364

RESUMO

Danuglipron is the most representative small-molecule agonist of the glucagon-like peptide-1 receptor (GLP-1R) and has received considerable attention due to positive results in the treatment of type 2 diabetes mellitus (T2DM) and obesity in clinical trials. However, hERG inhibition, lower activity than endogenous GLP-1, and a short action time represent limitations in terms of feasible application. In this study, we report a new class of 5,6-dihydro-1,2,4-triazine derivatives that serve to eliminate potential hERG inhibition caused by the piperidine ring of danuglipron. Applying systematic in vitro to in vivo screening, we have identified compound 42 as a highly potent and selective GLP-1R agonist, which delivers improved (7-fold) efficacy in stimulating cAMP accumulation compared with danuglipron and which exhibits acceptable drug-like properties. Furthermore, 42 significantly reduces glucose excursion and inhibits food intake of hGLP-1R Knock-In mice. These effects are longer-lasting than that shown by danuglipron, demonstrating feasibility in the treatment of T2DM and obesity.


Assuntos
Diabetes Mellitus Tipo 2 , Camundongos , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Obesidade/tratamento farmacológico
15.
ChemSusChem ; 16(17): e202300348, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37198132

RESUMO

Understanding the properties and structure of reactant water molecules at the electrolyte solution/electrode interface is relevant to know the mechanisms of hydrogen evolution reaction (HER). However, this approach has rarely been implemented due to the elusive local microenvironment in the vicinity of the catalyst. Taking the Ni-CeO2 heterostructure immobilized onto carbon paper (Ni-CeO2 /CP) as a model, the dynamic behavior of adsorbed intermediates during the reaction was measured by in situ surface-enhanced infrared absorption spectroscopy with attenuated total reflection configuration (ATR-SEIRAS). Theoretical calculations are used in combination to comprehend the potential causes of increased HER activity. The results show that the O-H bond of adsorbed water at the electrolyte solution/electrode interface becomes longer for promoting the dissociation of water and accelerating the kinetically slow Volmer step. In addition, forming the Ni-CeO2 heterostructure interface optimizes the hydrogen adsorption Gibbs free energy, thus increasing HER activity. Therefore, the Ni-CeO2 /CP electrode exhibits remarkably low HER overpotentials of 37 and 119 mV at 10 and 100 mA cm-2 , which are close to commercial Pt/C (16 and 102.6 mV, respectively).

16.
Eur J Pharmacol ; 953: 175812, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37245856

RESUMO

Diabetic nephropathy (DN) is a major cause of renal failure and urgently necessitates new therapeutic strategies. Magnesium lithospermate B (MLB) showed a good protective effect on kidney injure by oral administration, despite its extremely low bioavailability. The current study aimed to investigate its gut microbiota-targeted mechanism to explain the paradoxical properties of pharmacodynamics and pharmacokinetics. Here we show that MLB alleviated DN by recovering the dysfunction of gut microbiota and their associated metabolites in colon content, such as short-chain fatty acids and amino acids. Moreover, MLB significantly decreased uremic toxin levels in plasma, especially the p-cresyl sulfate. We further discovered that MLB could affect the metabolism of p-cresyl sulfate by suppressing the formation of its intestinal precursors, i.e. the microbiota-mediated conversion from 4-hydroxyphenylacetate to p-cresol. In addition, the inhibition effects of MLB were confirmed. MLB and its metabolite danshensu exhibited inhibitory effects on p-cresol formation mediated by three strains belonging to the genus Clostridium, Bifidobacterium, and Fusobacterium, respectively. Meanwhile, MLB decreased the levels of p-cresyl sulfate in plasma and p-cresol in feces caused by rectal administration of tyrosine in mice. To summarize, the results indicated that MLB ameliorated DN through modulating gut microbiota-associated p-cresyl sulfate metabolism. Together, this study provides new insights on the microbiota-targeted mechanism of MLB in intervening DN and a new strategy in lowering plasma uremic toxins by blocking the formation of their precursors in intestine.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Microbioma Gastrointestinal , Camundongos , Animais , Nefropatias Diabéticas/tratamento farmacológico , Toxinas Urêmicas
17.
Acta Pharmacol Sin ; 44(8): 1649-1664, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36997665

RESUMO

Excessive apoptosis of intestinal epithelial cell (IEC) is a crucial cause of disrupted epithelium homeostasis, leading to the pathogenesis of ulcerative colitis (UC). The regulation of Takeda G protein-coupled receptor-5 (TGR5) in IEC apoptosis and the underlying molecular mechanisms remained unclear, and the direct evidence from selective TGR5 agonists for the treatment of UC is also lacking. Here, we synthesized a potent and selective TGR5 agonist OM8 with high distribution in intestinal tract and investigated its effect on IEC apoptosis and UC treatment. We showed that OM8 potently activated hTGR5 and mTGR5 with EC50 values of 202 ± 55 nM and 74 ± 17 nM, respectively. After oral administration, a large amount of OM8 was maintained in intestinal tract with very low absorption into the blood. In DSS-induced colitis mice, oral administration of OM8 alleviated colitis symptoms, pathological changes and impaired tight junction proteins expression. In addition to enhancing intestinal stem cell (ISC) proliferation and differentiation, OM8 administration significantly reduced the rate of apoptotic cells in colonic epithelium in colitis mice. The direct inhibition by OM8 on IEC apoptosis was further demonstrated in HT-29 and Caco-2 cells in vitro. In HT-29 cells, we demonstrated that silencing TGR5, inhibition of adenylate cyclase or protein kinase A (PKA) all blocked the suppression of JNK phosphorylation induced by OM8, thus abolished its antagonizing effect against TNF-α induced apoptosis, suggesting that the inhibition by OM8 on IEC apoptosis was mediated via activation of TGR5 and cAMP/PKA signaling pathway. Further studies showed that OM8 upregulated cellular FLICE-inhibitory protein (c-FLIP) expression in a TGR5-dependent manner in HT-29 cells. Knockdown of c-FLIP blocked the inhibition by OM8 on TNF-α induced JNK phosphorylation and apoptosis, suggesting that c-FLIP was indispensable for the suppression of OM8 on IEC apoptosis induced by OM8. In conclusion, our study demonstrated a new mechanism of TGR5 agonist on inhibiting IEC apoptosis via cAMP/PKA/c-FLIP/JNK signaling pathway in vitro, and highlighted the value of TGR5 agonist as a novel therapeutic strategy for the treatment of UC.


Assuntos
Colite Ulcerativa , Colite , Humanos , Camundongos , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Sulfato de Dextrana/toxicidade , Fator de Necrose Tumoral alfa/metabolismo , Células CACO-2 , Sistema de Sinalização das MAP Quinases , Transdução de Sinais , Colite/induzido quimicamente , Apoptose , Mucosa Intestinal/metabolismo , Células Epiteliais/metabolismo , Camundongos Endogâmicos C57BL
18.
Eur J Med Chem ; 246: 114994, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36493615

RESUMO

Phenotypic screening still plays an important role in discovering new drugs, especially for diseases with complex pathogenesis, such as diabetes. As excessive gluconeogenesis is considered an important factor in the occurrence of hyperglycemia in T2DM, we previously screened our compounds library for active molecules which inhibit gluconeogenesis, resulting in the discovery of SL010110 with a unique mechanism, different from metformin and a thienopyridine derivative (DMT). The SARs study of SL010110 led to the discovery of 10v. Compared with SL010110, 10v showed improved anti-gluconeogenesis potency and pyruvate tolerance. A further pharmacokinetic study demonstrated that 10v displayed a relatively short half-life, moderate volume of distribution, and moderate to high oral bioavailability. In vivo chronic experiments showed an improved capability of 10v in ameliorating hyperglycemia as the 5 mg/kg 10v treatment greatly reduced non-fasting and fasting blood glucose levels, making it a promising candidate for the treatment of T2DM. The progression from in vitro screening to in vivo testing of the derivatized compounds provided a useful phenotypic screening drug discovery strategy based on the inhibition of gluconeogenesis.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperglicemia , Humanos , Glicemia/metabolismo , Ácidos Carboxílicos/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Descoberta de Drogas , Gluconeogênese , Hiperglicemia/tratamento farmacológico , Hiperglicemia/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/metabolismo , Fígado/metabolismo , Compostos Orgânicos/uso terapêutico
19.
Acta Pharmacol Sin ; 44(3): 596-609, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36085523

RESUMO

Promotion of hepatic glycogen synthesis and inhibition of hepatic glucose production are effective strategies for controlling hyperglycemia in type 2 diabetes mellitus (T2DM), but agents with both properties were limited. Herein we report coronarin A, a natural compound isolated from rhizomes of Hedychium gardnerianum, which simultaneously stimulates glycogen synthesis and suppresses gluconeogenesis in rat primary hepatocytes. We showed that coronarin A (3, 10 µM) dose-dependently stimulated glycogen synthesis accompanied by increased Akt and GSK3ß phosphorylation in rat primary hepatocytes. Pretreatment with Akt inhibitor MK-2206 (2 µM) or PI3K inhibitor LY294002 (10 µM) blocked coronarin A-induced glycogen synthesis. Meanwhile, coronarin A (10 µM) significantly suppressed gluconeogenesis accompanied by increased phosphorylation of MEK, ERK1/2, ß-catenin and increased the gene expression of TCF7L2 in rat primary hepatocytes. Pretreatment with ß-catenin inhibitor IWR-1-endo (10 µM) or ERK inhibitor SCH772984 (1 µM) abolished the coronarin A-suppressed gluconeogenesis. More importantly, we revealed that coronarin A activated PI3K/Akt/GSK3ß and ERK/Wnt/ß-catenin signaling via regulation of a key upstream molecule IRS1. Coronarin A (10, 30 µM) decreased the phosphorylation of mTOR and S6K1, the downstream target of mTORC1, which further inhibited the serine phosphorylation of IRS1, and subsequently increased the tyrosine phosphorylation of IRS1. In type 2 diabetic ob/ob mice, chronic administration of coronarin A significantly reduced the non-fasting and fasting blood glucose levels and improved glucose tolerance, accompanied by the inhibited hepatic mTOR/S6K1 signaling and activated IRS1 along with enhanced PI3K/Akt/GSK3ß and ERK/Wnt/ß-catenin pathways. These results demonstrate the anti-hyperglycemic effect of coronarin A with a novel mechanism by inhibiting mTORC1/S6K1 to increase IRS1 activity, and highlighted coronarin A as a valuable lead compound for the treatment of T2DM.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Camundongos , Ratos , Animais , Gluconeogênese , Glicogênio Hepático/metabolismo , beta Catenina/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Insulina/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Glucose/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Homeostase , Fosforilação
20.
Eur J Med Chem ; 242: 114697, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36029562

RESUMO

Ulcerative colitis (UC) is a gastrointestinal disease with complex etiology, and the shortage of the treatment further intensifies the need to discover new therapies based on novel mechanisms and strategies. TGR5 and DPP4 are beneficial to treat UC through multiple mechanisms, notably increasing GLP-2 levels by promoting secretion and inhibiting degradation respectively. However, some unwanted systemic effects caused by systemic exposure hinder development, especially the gallbladder-filling effects. Herein, we firstly reported a series of high-potency gut-restricted TGR5-DPP4 bifunctional molecules by gut-restriction and multitarget strategies to utilize the positive impacts of TGR5 and DPP4 on UC and avoid unwanted systemic effects. In particularly, racemic compound 15, a high-potency TGR5-DPP4 bifunctional molecule, showed favorable intestinal distribution, preferable efficacy in mice colitis model and good gallbladder safety. Therefore, the feasibility of gut-restricted TGR5-DPP4 bifunctional molecule was confirmed for the treatment UC, providing a new insight into the development of anti-UC drugs.


Assuntos
Colite Ulcerativa , Colite , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Dipeptidil Peptidase 4 , Modelos Animais de Doenças , Vesícula Biliar , Peptídeo 2 Semelhante ao Glucagon , Camundongos , Camundongos Endogâmicos C57BL , Receptores Acoplados a Proteínas G/metabolismo
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