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Hepatic fibrosis is intricately associated with dysregulation of gut microbiota and host metabolomes. Our previous studies have demonstrated that matrine can effectively reduce hepatosteatosis and associated disorders. However, it is poorly understood whether the gut microbiota involved in the attenuation of liver fibrosis by matrine. Herein we explored a novel mechanism of how oral administration of matrine alleviates liver fibrosis by modulating gut microbiota. Administration of matrine not only potently ameliorated liver fibrosis in carbon tetrachloride (CCl4)-induced mice, but also significantly preserved hepatic heat shock protein 72 (HSP72) in vivo and in vitro. Matrine was failed to reduce liver fibrosis when HSP72 upregulation was blocked by the HSP72 antagonist VER-155008. Also, consumption of matrine significantly alleviated gut dysbiosis and fecal metabonomic changes in CCl4-treated mice. Transplanted the faces of matrine-treated mice induced a remarkable upregulation of HSP72 and remission of fibrosis in liver in CCl4-exposed mice and inhibition of TGF-ß1-induced inflammatory response and epithelial-mesenchymal transition (EMT) in AML-12 cells. Furthermore, deficiency of HSP72 partly reversed the intestinal microbial composition that prevented matrine from reducing CCl4-induced liver fibrosis in mice. This study reveals the "gut microbiota-hepatic HSP72" axis as a key mechanism of matrine in reducing liver fibrosis and suggest that this axis may be targeted for developing other new therapies for liver fibrosis.
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Promoting energy expenditure is known to curb obesity and can be exploited for its treatment. Our previous study has demonstrated that activation of HSF1/PGC-1α axis efficiently induced mitochondrial biogenesis and adaptive oxidation and thus ameliorating lipid accumulation, however, whether it can be a therapeutic approach for metabolic disorders treatment needs explored. Here, a high-efficient and specific HSF1/PGC-1α activator screening system was established and the natural clinical liver-protecting agent matrine was identified as a robust HSF1/PGC-1α activator. Matrine treatment efficiently induced mitogenesis and thermogenic program in primary mouse adipose stem cell derived adipocytes by enriching HSF1 to the promoter of Pgc-1α. Deficiency of PGC-1α in adipocytes diminished the browning induction ability of matrine. Oral administration of matrine to the obese mice induced by high fat and high cholesterol diet increased energy expenditure and corrected the degeneration of thermogenesis in brown adipose tissue (BAT). Also, matrine treatment markedly induced the transformation of brown-like adipocytes in subcutaneous white adipose tissue (sWAT) via a mechanism of HSF1/PGC-1α, thereby attenuating obesity and myriads of metabolic disorders. This led to an improvement in adaptive thermogenesis to cold stimuli. These findings are of great significance in understanding the regulation mechanisms of the HSF1/PGC-1α axis in thermogenesis and providing a novel therapeutic approach for obesity treatment. Matrine may have potential therapeutic implications for the treatment of obesity in clinics.
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Tecido Adiposo Marrom , Termogênese , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Alcaloides , Animais , Metabolismo Energético , Fatores de Transcrição de Choque Térmico/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Quinolizinas , MatrinasRESUMO
BACKGROUND AND PURPOSE: Non-alcoholic steatohepatitis (NASH) is the more severe form of metabolic associated fatty liver disease (MAFLD) and no pharmacological treatment as yet been approved. Identification of novel therapeutic targets and their agents is critical to overcome the current inadequacy of drug treatment for NASH. EXPERIMENTAL APPROACH: The correlation between heat shock factor 1 (HSF1) levels and the development of NASH and the target genes of HSF1 in hepatocyte were investigated by chromatin-immunoprecipitation sequencing. The effects and mechanisms of SYSU-3d in alleviating NASH were examined in relevant cell models and mouse models (the Ob/Ob mice, high-fat and high-cholesterol diet and the methionine-choline deficient diet-fed mice). The actions of SYSU-3d in vivo were evaluated. KEY RESULTS: HSF1 is progressively reduced with mitochondrial dysfunction in NASH pathogenesis and activation of this transcription factor by its newly identified activator SYSU-3d effectively inhibited all manifestations of NASH in mice. When activated, the phosphorylated HSF1 (Ser326) translocated to nucleus and bound to the promoter of PPARγ coactivator-1α (PGC-1α) to induce mitochondrial biogenesis. Thus, increasing mitochondrial adaptive oxidation and inhibiting oxidative stress. The deletion of HSF1 and PGC-1α or recovery of HSF1 in HSF1-deficiency cells showed the HSF1/PGC-1α pathway was mainly responsible for the anti-NASH effects of SYSU-3d independent of AMP-activated protein kinase (AMPK). CONCLUSION AND IMPLICATIONS: Activation of HSF1 is a practical therapeutic approach for NASH treatment via the HSF1/PGC-1α/mitochondrial pathway and SYSU-3d can be considered as a potential candidate for the treatment of NASH.
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Fatores de Transcrição de Choque Térmico , Mitocôndrias , Hepatopatia Gordurosa não Alcoólica , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Fatores de Transcrição de Choque Térmico/agonistas , Fatores de Transcrição de Choque Térmico/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismoRESUMO
Metabolic-associated fatty liver disease (MAFLD) is the most common metabolic disease with a global prevalence of 25%. While MAFLD is serious and incurable at the later stage, it can be controlled or reversed at the early stage of hepatosteatosis originating from unhealthy diets. Recent laboratory evidence implicates a critical role of the mammalian target of rapamycin (mTOR)-autophagy signaling pathway in the pathogenesis of MAFLD induced by a high-fructose diet mimicking the overconsumption of sugar in humans. This review discusses the possible molecular mechanisms of mTOR-autophagy-endoplasmic reticulum (ER) stress in MAFLD. Based on careful analysis of recent studies, we suggest possible new therapeutic concepts or targets that can be explored for the discovery of new anti-MAFLD drugs.
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Autofagia , Frutose/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Estresse do Retículo Endoplasmático , Frutose/efeitos adversos , Humanos , Transdução de SinaisRESUMO
Consumption of diet rich in fat and cigarette smoking (CS) are independent risk factors of non-alcoholic steatohepatitis (NASH), and they often occur together in some populations. The present study investigated the mechanisms of high-fat diet (HFD) and CS, individually and in combination, on the pathogenesis of NASH in mice. C57BL/6 male mice were subjected to either a low-fat chow (CH) or HFD with or without mainstream CS-exposure (4 cigarettes/day, 5 days/ week for 14 weeks). HFD alone caused hepatosteatosis (2.5-fold increase in TG content) and a significant increase in 3-nitrotyrisine (by â¼40-fold) but without an indication of liver injury, inflammation or fibrosis. CS alone in CH-fed mice increased in Tnfα expression and macrophage infiltration by 2-fold and relatively less increase in 3-nitrotyrosine (18-fold). Combination of HFD and CS precipitated hepatosteatosis to NASH reflected by exacerbated makers of liver inflammation and fibrosis which were associated with much severe liver oxidative stress (90-fold increase in 3-nitrotyrisine along with 6-fold increase in carbonylated proteins and 56% increase in lipid oxidations). Further studies were performed to administer the antioxidant tempol to CS exposed HFD mice and the results showed that the inhibition of liver oxidative stress prevented inflammatory and fibrotic changes in liver despite persisting hepatosteatosis. Our findings suggest that oxidative stress is a key mechanism underlying CS-promoted progression of simple hepatosteatosis to NASH. Targeting hepatic oxidative stress may be a viable strategy in halting the progression of metabolic associated fatty liver disease.
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Cirrose Hepática/etiologia , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Estresse Oxidativo , Poluição por Fumaça de Tabaco/efeitos adversos , Animais , Antioxidantes/farmacologia , Óxidos N-Cíclicos/farmacologia , Dieta Hiperlipídica , Modelos Animais de Doenças , Progressão da Doença , Interleucina-1beta/metabolismo , Peroxidação de Lipídeos , Fígado/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/prevenção & controle , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Estresse Oxidativo/efeitos dos fármacos , Carbonilação Proteica , Marcadores de Spin , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease that can progress from simple hepatic steatosis to nonalcoholic steatohepatitis (NASH), and even further to liver cirrhosis or liver cancer. Overconsumption of high fat and/or carbohydrate are among the most common lifestyle factors that drive the development and progression of NAFLD. This review evaluates recent reports on the involvement of autophagy and endoplasmic reticulum (ER) stress in the pathogenesis of NAFLD. Here, we reveal a mechanism of an intrinsically linked axis of impaired autophagy and unresolved ER stress that mediates the development and progression of NAFLD resulting from the overconsumption of high fat and/or carbohydrate.
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Autofagia , Carboidratos da Dieta/efeitos adversos , Gorduras na Dieta/efeitos adversos , Estresse do Retículo Endoplasmático , Hepatopatia Gordurosa não Alcoólica/patologia , Dieta Hiperlipídica/efeitos adversos , HumanosRESUMO
Cigarette smoking (CS) is known to reduce body weight and this often masks its real effect on insulin action. The present study tested the hypothesis that CS can divert lipid deposition to muscles to offset the supposed benefit of reduced body weight gain on insulin signalling in this major site for glucose tolerance (or insulin action). The study was conducted in mice exposed to chronic CS followed by either a chow (CH) diet or a high-fat (HF) diet. CS increased triglyceride (TG) levels in both plasma and muscle despite a reduced body weight gain and adiposity. CS led to glucose intolerance in CH-fed mice and they retained the glucose intolerance that was induced by the HF diet. In adipose tissue, CS increased macrophage infiltration and the mRNA expression of TNFα but suppressed the protein expression of adipose triglyceride lipase and PPARγ. While CS increased hormone-sensitive lipase and suppressed the mRNA expression of leptin, these effects were blunted in HF-fed mice. These results imply that CS impairs insulin signalling in skeletal muscle via accumulated intramuscular lipids from lipolysis and lipodystrophy of adipose tissues. This may explain why smokers may not benefit from insulin sensitising effects of reduced body weight gain.
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Fumar Cigarros/efeitos adversos , Insulina/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Músculo Esquelético/metabolismo , Obesidade/metabolismo , Aumento de Peso/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Fumar Cigarros/genética , Fumar Cigarros/metabolismo , Fumar Cigarros/fisiopatologia , Dieta Hiperlipídica/efeitos adversos , Glucose/metabolismo , Humanos , Lipólise , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Obesidade/genética , Obesidade/fisiopatologia , PPAR gama/genética , PPAR gama/metabolismo , Triglicerídeos/metabolismoRESUMO
Discovery of novel anti-obesity agents is a challenging and promising research area. Based on our previous works, we synthesized 40 novel ß-indoloquinazoline analogues by altering the skeleton and introducing preferential side chains, evaluated their lipid-lowering activity and summarized the structure-activity relationships. In combination with an evaluation of the lipid-lowering efficacies, AMP-dependent activated protein kinase (AMPK) activating ability and liver microsomal stability, compound 23 (named as IQZ23) was selected for further studies. IQZ23 exerted a high efficacy in decreasing the triglyceride level (EC50 = 0.033 µM) in 3T3-L1 adipocytes. Mechanistic studies revealed the lipid-lowering activity of IQZ23 was dependent on the AMPK pathway by modulating ATP synthase activity. This activation was accompanied by mitochondrial biogenesis and oxidation capacity increased, and insulin sensitivity enhanced in pertinent cell models by various interventions. Correspondingly, IQZ23 (20 mg/kg, i.p.) treatment significantly reversed high fat and cholesterol diet (HFC)- induced body weight increases and accompanying clinical symptoms of obesity in mice but without indicative toxicity. These results indicate that IQZ23 could be a useful candidate for the treatment of obesity and related metabolic disorders.
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Fármacos Antiobesidade/farmacologia , Descoberta de Drogas , Doenças Metabólicas/tratamento farmacológico , Obesidade/tratamento farmacológico , Células 3T3-L1 , Animais , Fármacos Antiobesidade/síntese química , Fármacos Antiobesidade/química , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Colesterol , Dieta Hiperlipídica , Relação Dose-Resposta a Droga , Masculino , Doenças Metabólicas/induzido quimicamente , Doenças Metabólicas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Obesidade/induzido quimicamente , Obesidade/metabolismo , Relação Estrutura-AtividadeRESUMO
Albiflorin (AF) is a small molecule (MW 481) isolated from Paeoniae radix, a plant used as a remedy for various conditions with pathogenesis shared by metabolic diseases. Reported here is our characterization of its therapeutic profiles in three mouse models with distinctive pathological features of metabolic syndrome (MetS). Our results firstly showed that AF alleviated high fat (HF) induced obesity and associated glucose intolerance, suggesting its therapeutic efficacy for MetS. In the type 2 diabetes (T2D) model induced by a combination of HF and low doses of streptozotocin, AF lowered hyperglycaemia and improved insulin-stimulated glucose disposal. In the non-alcoholic steatohepatitis-like model resulting from a HF and high cholesterol (HF-HC) diet, AF reversed the increased liver triglyceride and cholesterol, plasma aspartate aminotransferase, and liver TNFα mRNA levels. Consistent with its effect in promoting glucose disposal in HF-fed mice, AF stimulated glucose uptake and GLUT4 translocation to the plasma membrane in L6 myotubes. However, these effects were unlikely to be associated with activation of insulin, AMPK, ER, or cellular stress signalling cascades. Further studies revealed that AF increased the whole-body energy expenditure and physical activity. Taken together, our findings indicate that AF exerts a therapeutic potential for MetS and related diseases possibly by promoting physical activity associated whole-body energy expenditure and glucose uptake in muscle. These effects are possibly mediated by a new mechanism distinct from other therapeutics derived from Chinese medicine.
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BACKGROUND AND PURPOSE: Non-alcoholic hepatic fatty liver disease (NAFLD) is a manifestation of the metabolic syndrome in the liver and non-alcoholic steatohepatitis (NASH) represents its advanced stage. R17 derived from bouchardatine, shows benefits in the metabolic syndrome, but has not been tested in the liver. The present study examined the pharmacological effects of R17 in a model of NAFLD/NASH and its mode of action. EXPERIMENTAL APPROACH: The effects of R17 were examined in mice fed a high-fat (HF) diet to induce the pathological characteristics of NAFLD/NASH and in cultures of HuH7 cells. We used histological and immunohistochemical techniques along with western blotting and siRNA. Generation of ROS and apoptosis were measured. KEY RESULTS: Administration of R17 (20 mg·kg-1 , i.p. every other day) for 5 weeks reversed HF-induced hepatic triglyceride content, inflammation (inflammatory cytokines and macrophage numbers), injury (hepatocyte ballooning and apoptosis, plasma levels of alanine aminotransferase and aspartate aminotransferase), and fibrogenesis (collagen deposition and mRNA expression of fibrosis markers). In cultured cells, R17 reduced cell steatosis from both lipogenesis and fatty acid influx. The attenuated inflammation and cell injury were associated with inhibition of both endoplasmic reticulum (ER) stress and oxidative stress. Notably, R17 activated the liver kinase B1-AMP-activated protein kinase (AMPK) pathway by inhibiting activity of ATP synthase, rather than direct stimulation of AMPK. CONCLUSION AND IMPLICATIONS: R17 has therapeutic potential for NAFLD/NASH. Its mode of action involves the elimination of ER and oxidative stresses, possibly via activating the LKB1-AMPK axis by inhibiting the activity of ATP synthase.
Assuntos
Adenosina Trifosfatases/antagonistas & inibidores , Alcaloides Indólicos/farmacologia , Alcaloides Indólicos/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Proteínas Quinases Ativadas por AMP/genética , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Dieta Hiperlipídica , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ácidos Graxos/metabolismo , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Macrófagos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Estresse Oxidativo/efeitos dos fármacos , Triglicerídeos/metabolismoRESUMO
The present study investigated the effects of matrine on non-alcoholic steatohepatitis (NASH) in mice induced by a methionine choline-deficient (MCD) diet and the mechanism involved. The study was performed in C57B/6J mice fed a MCD diet for 6 weeks to induce NASH with or without the treatment of matrine (100 mg/kg/day in diet). Metformin was used (250 mg/kg/day in diet) as a comparator for mechanistic investigation. Administration of matrine significantly reduced MCD-induced elevations in plasma ALT and AST but without changing body or liver fat content. Along with alleviating liver injury, matrine suppressed MCD-induced hepatic inflammation (indicated by TNFα, CD68, MCP-1, and NLRP3) and fibrosis (indicated by collagen 1, TGFß, Smad3, and sirius-red staining). In comparison, metformin treatment did not show any clear sign of effects on these parameters indicative of NASH. Further examination of the liver showed that matrine treatment rescued the suppressed HSP72 (a chaperon protein against cytotoxicity) and blocked the induction of mTOR (a key protein in a stress pathway). In keeping with the lack of the improvement of the NASH features, metformin did not show any significant effect against MCD-induced changes in HSP72 and mTOR. Matrine protects against MCD-induced development of NASH which is refractory to metformin treatment. Its anti-NASH effects involve enhancing HSP72 and downregulating mTOR but do not rely on amelioration of hepatosteatosis.
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The pathogenesis of Alzheimer's disease (AD) is characterized by both accumulation of ß-amyloid (Aß) plaque and formation of neurofibrillary tangles in the brain. Recent evidence shows that autophagy activation may potently promote intracellular Aß clearance. Thus targeting autophagy becomes a promising strategy for discovery of drug leads against AD. In the present study, we established a platform to discover autophagy stimulator and screened the lab in-house FDA-approved drug library. We found that anti-parasitic drug nitazoxanide (NTZ) was an autophagy activator and could efficiently improve learning and memory impairments in APP/PS1 transgenic mice. In BV2 cells and primary cortical astrocytes, NTZ stimulated autophagy and promoted Aß clearance by inhibiting both PI3K/AKT/mTOR/ULK1 and NQO1/mTOR/ULK1 signaling pathways; NTZ treatment attenuated LPS-induced inflammation by inhibiting PI3K/AKT/IκB/NFκB signaling. In SH-SY5Y cells and primary cortical neurons, NTZ treatment restrained tau hyperphosphorylation through inhibition of PI3K/AKT/GSK3ß pathway. The beneficial effects and related signaling mechanisms from the in vitro studies were also observed in APP/PS1 transgenic mice following administration of NTZ (90 mg·kg-1·d-1, ig) for 100 days. Furthermore, NTZ administration decreased Aß level and senile plaque formation in the hippocampus and cerebral cortex of APP/PS1 transgenic mice, and improved learning and memory impairments in Morris water maze assay. In conclusion, our results highlight the potential of NTZ in the treatment of AD.
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Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/antagonistas & inibidores , Antiparasitários/farmacologia , Modelos Animais de Doenças , Aprendizagem/efeitos dos fármacos , Transtornos da Memória/tratamento farmacológico , Tiazóis/farmacologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Células Cultivadas , Humanos , Transtornos da Memória/metabolismo , Camundongos , NitrocompostosRESUMO
Cancer metabolism is an attractive target of the therapeutic strategy for cancer. The present study identified bouchardatine (Bou) as a potent suppressor of rectal cancer growth by cycle-arresting independent of apoptosis. In cultured HCT-116 rectal cancer cells, Bou increased glucose uptake/oxidation and capacity of mitochondrial oxidation. These effects were associated with an upregulation of uncoupling protein 2 (UCP2) and the activation of its upstream Sirtuin 1 (SIRT1)/(Liver kinase B1) LKB1- (Adenosine monophosphate-activated protein kinase) AMPK axis. The pivotal role of UCP2 in the cancer-suppressing effect was demonstrated by overexpressing UCP2 in HCT-116â¯cells with similar metabolic effects to those produced by Bou. Interestingly, Bou activated peroxisome proliferators activated receptor γ coactivator 1α (PGC-1α) and recruited it to the promoter of UCP2 in HCT-116â¯cells along with deacetylation (thus activation) by SIRT1. The requirement of SIRT1 for the cancer-suppressing effect through the PGC-1α-UCP2 was confirmed by the reciprocal responses to Bou in HCT-116 with defected and overexpressed SIRT1. Whereas knockdown, mutation or pharmacological inhibition of SIRT1 all abolished Bou-induced deacetylation/activation of PGC-1α, the opposing effects were observed after overexpressing SIRT1. In mice, administration of Bou (50â¯mg/kg) also suppressed the growth of rectal cancer associated with increases the UCP2 expression and mitochondria capacity in the tumor. Collectively, our findings suggest that Bou has a therapeutic potential for the treatment of rectal cancer by disrupting the metabolic path of cancer cells via activating the PGC-1α-UCP2 axis with SIRT1 as its primary target.
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Alcaloides Indólicos/farmacologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Neoplasias Retais/tratamento farmacológico , Sirtuína 1/metabolismo , Proteína Desacopladora 2/metabolismo , Acetilação/efeitos dos fármacos , Aerobiose/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Alcaloides Indólicos/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oxirredução/efeitos dos fármacos , Neoplasias Retais/metabolismo , Neoplasias Retais/patologia , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Gluconeogenesis is a major source of hyperglycemia in patients with type 2 diabetes mellitus (T2DM), thus targeting gluconeogenesis to suppress glucose production is a promising strategy for anti-T2DM drug discovery. In our preliminary in vitro studies, we found that a small-molecule (E)-3-(2-(quinoline-4-yl)vinyl)-1H-indol-6-ol (QVO) inhibited the hepatic glucose production (HGP) in primary hepatocytes. We further revealed that QVO suppressed hepatic gluconeogenesis involving calmodulin-dependent protein kinase kinase ß- and liver kinase B1-adenosine monophosphate-activated protein kinase (AMPK) pathways as well as AMPK-independent mitochondrial function-related signaling pathway. To evaluate QVO's anti-T2DM activity in vivo, which was impeded by the complicated synthesis route of QVO with a low yield, we designed and synthesized 4-[2-(1H-indol-3-yl)vinyl]quinoline (IVQ) as a prodrug with easier synthesis route and higher yield. IVQ did not inhibit the HGP in primary hepatocytes in vitro. Pharmacokinetic studies demonstrated that IVQ was quickly converted to QVO in mice and rats following administration. In both db/db and ob/ob mice, oral administration of IVQ hydrochloride (IVQ-HCl) (23 and 46 mg/kg every day, for 5 weeks) ameliorated hyperglycemia, and suppressed hepatic gluconeogenesis and activated AMPK signaling pathway in the liver tissues. Furthermore, IVQ caused neither cardiovascular system dysfunction nor genotoxicity. The good druggability of IVQ has highlighted its potential in the treatment of T2DM and the prodrug design for anti-T2DM drug development.
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Diabetes Mellitus Tipo 2/tratamento farmacológico , Gluconeogênese/efeitos dos fármacos , Hipoglicemiantes/uso terapêutico , Indóis/uso terapêutico , Pró-Fármacos/uso terapêutico , Quinolinas/uso terapêutico , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Complexo I de Transporte de Elétrons/antagonistas & inibidores , Complexo III da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Ativadores de Enzimas/uso terapêutico , Ativadores de Enzimas/toxicidade , Inibidores Enzimáticos/uso terapêutico , Inibidores Enzimáticos/toxicidade , Glucose-6-Fosfatase/antagonistas & inibidores , Hepatócitos/efeitos dos fármacos , Hipoglicemiantes/toxicidade , Indóis/toxicidade , Fígado/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Fosfoenolpiruvato Carboxiquinase (GTP)/antagonistas & inibidores , Pró-Fármacos/toxicidade , Quinolinas/toxicidade , Transdução de Sinais/efeitos dos fármacosRESUMO
Chronic Obstructive Pulmonary Disease (COPD) is a major incurable global health burden and will become the third largest cause of death in the world by 2030. It is well established that an exaggerated inflammatory and oxidative stress response to cigarette smoke (CS) leads to, emphysema, small airway fibrosis, mucus hypersecretion, and progressive airflow limitation. Current treatments have limited efficacy in inhibiting chronic inflammation and consequently do not reverse the pathology that initiates and drives the long-term progression of disease. In particular, there are no effective therapeutics that target neutrophilic inflammation in COPD, which is known to cause tissue damage by degranulation of a suite of proteolytic enzymes including neutrophil elastase (NE). Matrine, an alkaloid compound extracted from Sophora flavescens Ait, has well known anti-inflammatory activity. Therefore, the aim of the present study was to investigate whether matrine could inhibit CS-induced lung inflammation in mice. Matrine significantly reduced CS-induced bronchoalveolar lavage fluid (BALF) neutrophilia and NE activity in mice. The reduction in BALF neutrophils in CS-exposed mice by matrine was not due to reductions in pro-neutrophil cytokines/chemokines, but rather matrine's ability to cause apoptosis of neutrophils, which we demonstrated ex vivo Thus, our data suggest that matrine has anti-inflammatory actions that could be of therapeutic potential in treating CS-induced lung inflammation observed in COPD.
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Alcaloides/farmacologia , Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Fumar Cigarros , Lesão Pulmonar/prevenção & controle , Pulmão/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Quinolizinas/farmacologia , Animais , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Elastase de Leucócito/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Lesão Pulmonar/imunologia , Lesão Pulmonar/metabolismo , Lesão Pulmonar/patologia , Masculino , Camundongos Endogâmicos BALB C , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/patologia , Peroxidase/metabolismo , Fumaça , MatrinasRESUMO
Diabetic cardiomyopathy (DCM) is a form of idiopathic heart disease, with signs including hypertrophy of myocardial cells, hypertensionindependent fibrosis and coronary artery disease. Considering the involvement of dimethylarginine dimethylaminohydrolase 2 (DDAH2) in diabetes, it was hypothesized that DDAH2 may be beneficial to cardiac function and myocardial fibrosis during the progression of DCM with involvement of the DDAH/asymmetric NG, NGdimethylLarginine (ADMA)/nitric oxide synthase (NOS)/nitric oxide (NO) signaling pathway. Following establishment of diabetic rat models, diabetesrelated blood biochemical indices and cardiac function were measured in diabetic rats treated with lentivirus expressing DDAH2, short hairpin RNA against DDAH2, or LNNA (inhibitor of NOS) to identify the roles of DDAH2 in DCM. The functional roles of DDAH2 in DCM were further determined through detection of the levels of collagen I, matrix metalloproteinase 2 (MMP2) and tissue inhibitor of metalloproteinase 2 (TIMP2). The H9C2 myocardial cell line was selected for in vitro experiments. The effects of DDAH2 on the migration of myocardial cells under high glucose conditions were also examined. To further investigate the underlying regulatory mechanism of DDAH2 in DCM, the contents of ADMA and NO, and the activities of DDAH and NOS were observed. The DCM model rats treated with DDAH2 exhibited reduced left ventricular enddiastolic pressure, and decreased blood glucose, total cholesterol, triglyceride, fasting blood glucose, and fasting insulin levels, but exhibited increased left ventricular systolic pressure and maximum rate of left ventricular pressure rise/fall levels in myocardial tissues. Myocardial cells under high glucose conditions treated with DDAH2 showed reductions in collagen I, MMP2 and TIMP2, indicating that DDAH2 reduced cell migration. Decreased levels of ADMA and NO but increased levels of DDAH and NOS were observed following treatment with DDAH2, indicating that the DDAH/ADMA/NOS/NO pathway was activated. These results reveal that the overexpression of DDAH2 attenuates myocardial fibrosis and protects against DCM through activation of the DDAH/ADMA/NOS/NO pathway in DCM rats. These results indicate that DDAH2 is a potential therapeutic candidate for the treatment of DCM.
Assuntos
Amidoidrolases/fisiologia , Arginina/análogos & derivados , Cardiomiopatias Diabéticas/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/metabolismo , Animais , Arginina/metabolismo , Linhagem Celular , Cardiomiopatias Diabéticas/sangue , Cardiomiopatias Diabéticas/tratamento farmacológico , Fibrose , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Inibidor Tecidual de Metaloproteinase-2/metabolismoRESUMO
Postnatal overconsumption of fat is believed to increase the susceptibility to metabolic disease in the later life. Here we examined whether prior exposure to high fat (HF) in the adulthood may also accelerate the development of metabolic disorders in mice. Adult mice (12 weeks) were pre-exposed to two episodes of an HF diet each for 2 weeks followed by 2 weeks of washout with a low-fat diet. The mice were then fed the same HF diet for 6 weeks. Unexpectedly, prior exposures to HF diet significantly alleviated body weight gain, visceral adiposity and glucose/insulin intolerance during the period of last HF feeding. These protective effects were evident without changing calorie intake and were specific for HF, but not high fructose (HFru) diet. Following the HF prior exposures was increases in plasma fibroblast growth factor 21 (FGF21), the expressions of phospho-AMP-activated protein kinase (pAMPK), mitochondrial complex II and the expression of uncoupling protein (UCP) 3 in muscle and UCP1 and Sirtuin 1 (SIRT1) in adipose tissue. However, in the liver there was no significant change in pAMPK, SIRT1 expression or the capacity of glucose production. These findings indicated that, instead of exacerbating metabolic conditions, prior exposures to HF diet lead to the preconditioning against subsequent overload of HF, possibly involving FGF21-associated enhancement of markers for metabolic capacity in muscle and adipose tissue. This paradoxical phenomenon may offer a unique paradigm to identify factors and explore dietary ingredients with beneficial effects for the control of the metabolic syndrome in humans.
Assuntos
Tecido Adiposo/metabolismo , Dieta Hiperlipídica/efeitos adversos , Síndrome Metabólica/etiologia , Músculo Esquelético/metabolismo , Adiposidade , Animais , Dieta Hiperlipídica/métodos , Fatores de Crescimento de Fibroblastos/metabolismo , Glucose/metabolismo , Teste de Tolerância a Glucose , Insulina/metabolismo , Masculino , Síndrome Metabólica/metabolismo , Camundongos Endogâmicos C57BL , Aumento de PesoRESUMO
The present study investigated the efficacy of the hepatoprotective drug matrine (Mtr) for its new application for hepatosteatosis and associated disorders in glucose homeostasis. The study was performed in two nutritional models of hepatosteatosis in mice with various abnormal glucose homeostasis: (1) high-fructose diet (HFru) induced hepatosteatosis and glucose intolerance from hepatic, and (2) hepatosteatosis and hyperglycemia induced by high-fat (HF) diet in combination with low doses of streptozotocin (STZ). Administration of Mtr (100 mg/kg every day in diet for 4 weeks) abolished HFru-induced hepatosteatosis and glucose intolerance. These effects were associated with the inhibition of HFru-stimulated de novo lipogenesis (DNL) without altering hepatic fatty acid oxidation. Further investigation revealed that HFru-induced endoplasmic reticulum (ER) stress was inhibited, whereas heat-shock protein 72 (an inducible chaperon protein) was increased by Mtr. In a type 2 diabetic model induced by HF-STZ, Mtr reduced hepatosteatosis and improved attenuated hyperglycemia. The hepatoprotective drug Mtr may be repurposed for the treatment of hepatosteatosis and associated disorders in glucose homeostasis. The inhibition of ER stress associated DNL and fatty acid influx appears to play an important role in these metabolic effects.
Assuntos
Alcaloides/uso terapêutico , Reposicionamento de Medicamentos , Fígado Gorduroso/tratamento farmacológico , Intolerância à Glucose/tratamento farmacológico , Substâncias Protetoras/uso terapêutico , Quinolizinas/uso terapêutico , Adiposidade/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ácidos Graxos/metabolismo , Frutose/efeitos adversos , Frutose/metabolismo , Proteínas de Choque Térmico HSP72/metabolismo , Homeostase/efeitos dos fármacos , Lipogênese/efeitos dos fármacos , Fígado/fisiopatologia , Camundongos Endogâmicos C57BL , Triglicerídeos/metabolismo , MatrinasRESUMO
Diabetes-induced injury of myocardium, defined as diabetic cardiomyopathy (DCM), accounts for significant mortality and morbidity in diabetic population. Alleviation of DCM by a potent drug remains considerable interests in experimental and clinical researches because hypoglycemic drugs cannot effectively control this condition. Here, we explored the beneficial effects of isosteviol sodium (STVNa) on type 1 diabetes-induced DCM and the potential mechanisms involved. Male Wistar rats were induced to diabetes by injection of streptozotocin (STZ). One week later, diabetic rats were randomly grouped to receive STVNa (STZ/STVNa) or its vehicle (STZ). After 11 weeks of treatment or 11 weeks treatment following 4 weeks of removal of the treatment, the cardiac function and structure were evaluated and related mechanisms were investigated. In diabetic rats, oxidative stress, inflammation, blood glucose and plasma advanced glycation end products (AGEs) were significantly increased, whereas superoxide dismutase 2 (SOD-2) expression and activity were decreased. STVNa treatment inhibited cardiac hypertrophy, fibrosis and inflammation, showed similar ratio of heart to body weight and antioxidant capacities almost similar to the normal controls, which can be sustained at least 4 weeks. Moreover, STVNa inhibited diabetes-inducted stimulation of both extracellular signal-regulated kinase (ERK) and nuclear factor κB (NF-κB) signal pathways. However, blood glucose, plasma AGE and insulin levels were not altered by STVNa treatment. These results indicate that STVNa may be developed into a potent therapy for DCM. The mechanism underlying this therapeutic effect involves the suppression of oxidative stress and inflammation by inhibiting ERK and NF-κB without changing blood glucose or AGEs.
Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Cardiomiopatias Diabéticas/prevenção & controle , Diterpenos do Tipo Caurano/uso terapêutico , Hipoglicemiantes/uso terapêutico , Animais , Antioxidantes/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/patologia , Diterpenos do Tipo Caurano/farmacologia , Regulação para Baixo/efeitos dos fármacos , Coração/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , NF-kappa B/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , EstreptozocinaRESUMO
Inhibition of the differentiation of adipocytes and reduced lipid synthesis are efficacious approaches for treating obesity-related metabolic disorders. Bouchardatine (Bou) is a natural alkaloid that has been reported to moderately inhibit the differentiation of 3T3-L1 cells without inducing toxicity. To explore the importance of aldehyde group at 8a-position of Bou and optimize the activity, we synthesized 35 (31 novel) compounds by discarding or replacing aldehyde group with halogen and introducing different amine chains at 5-position of Bou. The lipid-lowering activity was evaluated using a cell-based screening system. The substitution of the group at the 8a-position of compounds was important for its lipid-lowering activity, and the SAR was discussed. The selective compound 6e showed a 93-fold increase in its lipid-lowering effect (EC50â¯=â¯0.24⯵M) compared with Bou (EC50â¯≈â¯25⯵M). Further mechanistic studies revealed that compound 6e activated AMP-activated protein kinase (AMPK) pathway and inhibited MCE activity to block cell proliferation and induce cell cycle arrest at the early stage of differentiation, thus decreasing the expression of adipogenic factors and fatty acid synthesis-related proteins.