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ObjectiveTo investigate the effect of Gegen Qinliantang on glucose and lipid metabolism in the rat model of catch-up growth （CUG） induced by a high-fat diet and the underlying mechanism. MethodA total of 60 SD rats were randomized into a normal control group （n=18） and a modeling group （n=42）. The rat model of CUG was established with a restricted diet followed by a high-fat diet， and the changes of general status and body weight were observed. The levels of fasting blood glucose （FBG）， fasting insulin （FINS）， triglyceride （TG）， and total cholesterol （TC） were measured in 6 rats in each group at the end of the 4th and 8th week， respectively. The homeostasis model assessment of insulin resistance index （HOMA-IR） was calculated， and the insulin sensitivity and body composition changes of CUG rats were evaluated. The successfully modeled rats were assigned into 6 groups： normal control， model， high-， medium-， and low-dose Gegen Qinliantang （2.5， 5， 10 g·kg-1）， and pioglitazone （3.125 mg·kg-1）. The rats were administrated with corresponding drugs by gavage for 6 weeks， and the normal control group and model group were administrated with the same amount of normal saline. During the experiment period， the changes of body weight were recorded， and the FBG， FINS， HOMA-IR， TG， and TC were determined at the end of the experiment. Hematoxylin-eosin （HE） staining was employed to observe the pathological changes of skeletal muscle in rats. The levels of reactive oxygen species （ROS） and malondialdehyde （MDA） in the skeletal muscle were measured strictly according to the manuals of the reagent kits. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was performed to measure the mRNA levels of silencing information regulator 1 （SIRT1）， peroxisome proliferator-activated receptor-gamma coactivator1α （PGC1α）， and nuclear respiratory factor 1 （Nrf1） in the skeletal muscle. Western blot and immunohistochemistry were employed to assess the expression of SIRT1， PGC1α， and Nrf1 in the skeletal muscle. ResultCompared with the normal control group， the model group presented elevated levels of FBG， FINS， TG， and TC （P<0.05， P<0.01）， increased HOMA-IR （P<0.01）， increased diameter of muscle fibers and adipocytes between muscle cells in the skeletal muscle， rising levels of ROS and MDA in the skeletal muscle （P<0.01）， and down-regulated mRNA and protein levels of SIRT1， PGC1α， and Nrf1 （P<0.05， P<0.01）. Compared with the model group， Gegen Qinliantang （especially the medium and high doses） and pioglitazone decreased the body weight， FINS， HOMA-IR， and TG （P<0.05， P<0.01） and reduced interstitial components such as intermuscular fat in the skeletal muscles and the diameter of muscle fibers. Furthermore， the drugs lowerd the levels of ROS and MDA （P<0.05， P<0.01） and up-regulated the mRNA and protein levels of SIRT1， PGC1α， and Nrf1 （P<0.05， P<0.01） in the skeletal muscle. ConclusionGegen Qinliantang can ameliorate the glucose and lipid metabolism disorders and insulin resistance in CUG rats by regulating the SIRT1/PGC1α/Nrf1 signaling pathway.

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BACKGROUND: Acute lung injury (ALI) is an intractable medical problem linked with to high morbidity and mortality all over the worldglobally. The prognosis of advanced acute lung injury remains persistently poor due to its underlying mechanisms remain unclear.Despite advancements in medical research, the its prognosis of advanced ALI remains persistently poor due to unclear underlying mechanisms. We aimed to investigate the protective effects of silencing information regulator 1 (SIRT1) on lipopolysaccharide (LPS)-induced acute lung injuryALI and to reveal its underlying molecular mechanism. METHODS: Male Sprague--Dawley rats were divided grouped into 4 groupsfour: normal saline group (group NS), lipopolysaccharide group (group L), SIRT1 activator SRT1720-pretreated group (group S), and SIRT1 inhibitor EX527- pretreated group (group E). Rats They were intranasally dripped with LPS to establish the model of ALI modelsacute lung injury respectively. We investigated the effect of SIRT1 on acute lung injury by analysing We analyzed the CT images of the rat lungs and used, HE staining, lung wet-to-dry ratio, inflammatory factor expression, lung injury marker expression, immunohistochemistry, and related mRNA expression to determine the effect of SIRT1 on ALI. RESULTS: Our results show that LPS induction produced resulted in acute lung injury, ALI and disrupting disrupted normal SIRT1 expression, which led to the overexpression of STAT3, TLR4, TNF-ɑ, and IL-6 and suppression of Cav-1 expression. Upregulation The upregulation of Cav-1 protein and mRNA following the administration of an SIRT1 agonist resulted in reduced lung injury. SRT1720 pretreatment was closely associated with reduced expressions of STAT3,TLR4, TNF-ɑ, and IL-6. ALI lung injury was more severeworsened after administration of SIRT1 inhibitors, and the changes in the above indicators were reversed. CONCLUSIONS: These results suggest that SIRT1 may protect against LPS-induced acute lung injuryALI via by counteracting inflammatory remissionion, and this protective effect might may be mediated by suppressing STAT3 to activate the expression ofinduce Cav-1 expression.

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Lesión Pulmonar Aguda , Lipopolisacáridos , Animales , Masculino , Ratas , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/genética , Lesión Pulmonar Aguda/metabolismo , Caveolina 1/genética , Caveolina 1/metabolismo , Interleucina-6/metabolismo , Lipopolisacáridos/farmacología , Pulmón , Ratas Sprague-Dawley , ARN Mensajero/metabolismo , Transducción de Señal , Sirtuina 1/genética , Sirtuina 1/metabolismo , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Regulación hacia Arriba

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Objective To investigate the effect of total alkaloids of Rhizoma Corydalis(TAC)on the expression of silencing information regulator 1(Sirt1)/tumor suppressor P53 protein signaling pathway-related proteins in the hippocampus of rats with chronic cerebral ischemia(CCH),and to explore its mechanism.Methods The rats were randomly divided into Sham operation group,model group,TAC high-dose group(14 mg/kg)and TAC low-dose group(7 mg/kg),with 6 rats in each group.A modified bilateral common carotid artery permanent occlusion method(BCCAO)was used to establish a rat model of CCH,and only bilateral common carotid arteries were separated in the Sham group.After the modeling was completed,each group was given the corresponding drug or isotonic saline by gavage,once a day,and the treatment lasted for 14 days.Hematoxycin-eosin staining was used to observe the pathological changes in the hippocampus of rats,in situ terminal deoxynucleotidyl transferase-mediated deoxyuridinetriphate-biotin nick end labeling assay(TUNEL)was used to detect neuronal apoptosis,and Western blotting and immunohistochemistry were used to detect expression of Sirt1,P53,P53 positive apoptosis regulator(PUMA),B-cell lymphocytoma-2(Bcl-2)protein,Bcl-2-related X protein(BAX),respectively in the hippocampus of rats.Results(1)There were significant differences in the number of apoptotic cells and apoptosis rate among the four groups(F-values were 71.417 and 76.835,respectively,both P＜0.01).There were statistically significant differences in the mean integral optical density values of Sirt1,P53,PUMA,BAX and Bcl-2 protein positive expression areas among the four groups(F-values were 1 178.390,42.465,867.413,110.656 and 131.801,all P＜0.01).There were significant differences in the relative expression levels of Sirt1,P53,PUMA,BAX and Bcl-2 among the four groups(F-values were 9.497,11.863,58.552,186.855 and 12.466,all P＜0.01).(2)Compared with the Sham operation group,the neuronal arrangement of brain tissue in the hippocampus of the model group was disordered,the nuclear consolidation increased,and the glial cells and inflammatory cells increased significantly,and the number and apoptosis rate of neurons in the hippocampus of the model group increased significantly(respectively[10.8±1.5]cells vs.[2.0±0.9]cells and[35.5±4.5]％vs.[6.2±2.6]％;both P＜0.05),and the average integral optical density values of the positive expression areas of Sirt1 and Bcl-2 proteins decreased significantly(84.6±6.6 vs.244.6±4.9,138.5±6.7 vs.210.9±10.0;both P＜0.05),the average integral optical density values of P53,PUMA and BAX proteins were significantly increased(156.8±11.6 vs.93.5±11.6,151.3±3.3 vs.38.0±4.0,87.0±5.0 vs.38.4±5.5;all P＜0.05),the relative expression levels of Sirt1 and Bcl-2 proteins were significantly decreased(0.51±0.07 vs.0.74±0.07,0.36±0.03 vs.0.53±0.05;both P＜0.05),and the relative expression levels of P53,PUMA and BAX proteins were significantly increased(0.37±0.06 vs.0.21±0.02,0.62±0.06 vs.0.23±0.02,1.08±0.06 vs.0.45±0.03;all P＜0.05).(3)Compared with the model group,the hippocampal tissue structure of the high-dose and low-dose TAC groups was relatively compact and uniform,the neurons were neatly arranged,and the cell structure was relatively clear and complete,while the number of neuronal apoptotic cells and the apoptosis rate decreased significantly(respectively[3.8±0.7]cells vs.[6.2±1.2]cells,[12.4±2.8]％vs.[20.2±3.9]％;both P＜0.05),and the average integrated optical density values of the positive expression areas of Sirt1 and Bcl-2 proteins(the high-dose and low-dose TAC groups:Sirt1 150.0±4.8,131.3±1.3,and Bcl-2 207.1±7.4,169.5±3.9,respectively)were significantly increased(both P＜0.05),the average integral optical density values of P53,PUMA and BAX proteins were significantly decreased(the high-dose and low-dose TAC groups:P53 105.9±8.8,115.5±9.0,and PUMA56.8±5.1,74.4±3.9,and BAX40.5±5.6,48.4±5.0,respectively,all P＜0.05),the relative expression levels of Bcl-2 protein(the high-dose and low-dose TAC groups:0.53±0.05,0.47±0.02,respectively)were significantly increased(P＜0.05),the relative expression levels of P53(the high-dose and low-dose TAC groups:0.21±0.02,0.24±0.04,respectively),PUMA(the high-dose and low-dose TAC groups:0.36±0.02,0.28±0.04,respectively)and BAX proteins(the high-dose and low-dose TAC groups:0.52±0.02,0.54±0.03,respectively)were significantly decreased(all P＜0.05),the relative expression level of Sirt1 protein in the TAC high-dose group was significantly decreased(0.71±0.05,P＜0.05),and the relative expression level of Sirt1 protein in the TAC low-dose group was not statistically significant(0.52±0.08,P＞0.05).Conclusion TAC can alleviate neuronal damage and reduce the apoptosis rate of neurons in the hippocampus of CCH rats,and the mechanism may be related to the activation of Sirt1/P53 pathway,inhibition of P53 protein activity,and thus the expression level of apoptosis-related proteins in the downstream of TAC.

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Lead (Pb) exposure damages synaptic structural plasticity that results in cognitive impairment. Resveratrol, a natural polyphenolic compound, is one of the most potent agonists of silencing information regulator 1 (SIRT1) discovered to date. However, the effects of SIRT1 on synaptic functional plasticity in early life Pb exposure are not well studied. Herein, the purpose of this study is to investigate the expression of synaptic markers and SIRT1 in rats exposed to Pb and to evaluate the regulatory effect of resveratrol during this process. The Pb exposed male SD pups were treated with resveratrol (50 mg/kg/d) or EDTA (150 mg/kg/d) followed by hippocampal and blood sampling for analysis at postnatal day 21 (PND21). In the Morrris water maze test, resveratrol treatement protected the rats against Pb-induced impairment of learning and memory (P < 0.05). Resveratrol also enhanced the expression of brain-derived neurotrophic factor (BDNF, P < 0.001 vs 0.2% Pb group), and reversed the effects of Pb exposure on SIRT1(P < 0.001 vs 0.2% Pb group). The DG, CA1 and CA3 regions of the hippocampus showed a considerable increase in the expression of pre- and postsynaptic proteins (P < 0.001 vs 0.2% Pb group). In conclusion, our study demonstrated that resveratrol, through the activation of SIRT1, played a protective role against Pb-induced defects in synaptic plasticity, and suggested a new potential adjuvant treatment for Pb poisoning.

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Intoxicación por Plomo/tratamiento farmacológico , Resveratrol/farmacología , Sirtuina 1/metabolismo , Animales , Encéfalo/metabolismo , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Disfunción Cognitiva/inducido químicamente , Disfunción Cognitiva/metabolismo , Hipocampo/metabolismo , Plomo/toxicidad , Masculino , Plasticidad Neuronal/efectos de los fármacos , Ratas , Ratas Sprague-Dawley

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Objective:To evaluate the role of silencing information regulator 1 (SIRT1)/nuclear factors E2-related factor2 (Nrf2) signaling pathway in berberine-induced reduction of renal ischemia-reperfusion (I/R) injury in mice.Methods:Thirty SPF healthy male C57BL/6 mice, aged 6-8 weeks, weighing 18-22 g, were divided into 5 groups ( n=6 each) using a random number table method: sham operation group (S group), renal I/R group (RIR group), berberine+ I/R group (B group), berberine+ I/R+ SIRT1 inhibitor EX527 group (BE group) and berberine+ I/R+ Nrf2 inhibitor ATRA group (BA group). After the right kidney was removed, the left renal artery was clamped for 45 min followed by reperfusion to establish the model of renal I/R injury.In B, BE, and BA groups, berberine 100 mg·kg -1·d -1 was given for intragastric administration at 14 days before surgery.In group BE and group BA, EX527 5 mg·kg -1·d -1 and ATRA 10 mg·kg -1·d -1 were injected intraperitoneally at 3 days before surgery, respectively.The equal volume of normal saline was given for 14 consecutive days in group S and group RIR.Blood samples were collected from orbital vein at 24 h of reperfusion for measurement of serum blood urea nitrogen (BUN) and creatinine (Cr) concentrations, for determination of the interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) contents (by enzyme-linked immunosorbent assay) and expression of SIRT1, Nrf2, apoptosis-associated speck-like protein containing CARD (ASC), caspase-1, nucleotide-binding oligomerization domain-like receptor containing pyrin domain (NLRP3) (by Western blot) and for examination of the pathological changes of renal tubules (with a light microscope). The damage to the renal tubules was scored. Results:Compared with group S, the concentrations of serum Cr and BUN, the contents of renal IL-1β and TNF-α and renal tubular injury score were significantly increased in RIR, B, BE and BA groups, the expression of SIRT1, Nrf2, ASC, caspase-1 and NLRP3 was up-regulated in RIR, BE and BA groups, and the expression of SIRT1, Nrf2, caspase-1 and NLRP3 was up-regulated in group B ( P<0.05). Compared with group RIR, the concentrations of serum Cr and BUN, the contents of renal IL-1β and TNF-α and renal tubular injury score were significantly decreased in B, BE and BA groups, the expression of SIRT1 and Nrf2 in group B, Nrf2 and ASC in BE group and SIRT1, ASC and caspase-1 in BA group was up-regulated, and the expression of ASC, caspase-1 and NLRP3 in group B, SIRT1 and NLRP3 in BE group and Nrf2 in BA group was down-regulated ( P<0.05). Compared with group B, the serum concentrations of Cr and BUN, the contents of IL-1β and TNF-α and renal tubular injury score were significantly increased in BE and BA groups, the expression of ASC, caspase-1 and NLRP3 in BE and BA groups was up-regulated, and the expression of SIRT1 in BE and Nrf2 in BA groups was down-regulated ( P<0.05). Conclusion:SIRT1/Nrf2 signaling pathway is involved in the process of berberine-induced reduction of renal I/R, which is related to inhibiting pyroptosis in mice.