Effect of Linggui Zhugantang on Mitochondrial Fusion-fission and Sirt3/ AMPK Signaling Pathway in Chronic Heart Failure Rats After Myocardial Infarction / 中国实验方剂学杂志

ObjectiveTo investigate the effects of Linggui Zhugantang on mitochondrial fission and fusion and silencing information regulator 3（Sirt3）/adenosine monophosphate dependent protein kinase （AMPK） signaling pathway in chronic heart failure （CHF） rats after myocardial infarction （MI）. MethodSD rats randomly divide into sham operation group （normal saline ，thread only without ligature）， model group （normal saline， ligation of the left anterior descending coronary artery proximal to the heart）， Linggui Zhugantang group （4.8 g·kg-1） and Captopril group （0.002 57 g·kg-1）， with 10 rats in each group. Administere drug continuously for 28 days. Echocardiography detected cardiac function parameters. Hematoxylin eosin （HE） staining observed the pathological changes of the heart. Immunofluorescence detected the levels of reactive oxygen species （ROS）. JC-1 detect mitochondrial membrane potential. Colorimetry measure adenosine triphosphate （ATP）， superoxide dismutase （SOD）， malondialdehyde （MDA）， mitochondrial respiratory chain complex activity （Ⅰ-Ⅳ）. TdT-mediated dUTP nick end labeling （TUNEL） staining detected the apoptosis rate of myocardial tissue. Western blot detected protein expression levels of Sirt3， phosphorylated AMPK （p-AMPK）， phosphorylated dynamic-related protein 1（p-Drp1）， mitochondrial fission protein 1（Fis1）， mitochondrial fission factor （MFF）， optic atrophy protein 1（OPA1）. ResultCompared to the sham group， the left ventricular end diastolic diameter （LVIDd） and left ventricular end systolic diameter （LVIDs） were significantly increased in model group （P<0.01）， while the left ventricular short axis shortening rate （LVFS） and left ventricular ejection fraction （LVEF） were significantly decreased （P<0.01）. There were inflammatory cell infiltration and obvious pathological injury in myocardial tissue. ROS， MDA levels and myocardial cell apoptosis rate were significantly increased （P<0.01）， SOD level， ATP content， and membrane potential were significantly decreased （P<0.01）. The activity of mitochondrial respiratory chain complexes （Ⅰ-Ⅳ） was significantly decreased （P<0.01）. Levels of p-Drp1， Fis1， MFF proteins were significantly up-regulated （P<0.01）， while Sirt3， p-AMPK， OPA1 proteins level were significantly down-regulated （P<0.01）. Compared with model group， LVIDd and LVIDs were significantly decreased （P<0.01）， LVEF and LVFS were significantly increased （P<0.01）. Inflammatory cell infiltration and pathological damage of myocardial tissue were significantly relieved. ROS， MDA levels and myocardial cell apoptosis rate were significantly decreased in Linggui Zhugantang group and Captopril group （P<0.01）， SOD level， ATP content， and membrane potential significantly increased （P<0.01）. The activity of mitochondrial respiratory chain complexes （Ⅰ-Ⅳ） increased significantly （P<0.01），and p-Drp1， Fis1， MFF protein levels were significantly down-regulated （P<0.01）， Sirt3， p-AMPK， OPA1 protein were significantly up-regulated （P<0.01）. ConclusionLinggui Zhugantang can alleviate oxidative stress and apoptosis damage of myocardial cells， maintain mitochondrial function stability， and its effect may be related to mitochondrial mitosis fusion and Sirt3/AMPK signaling pathway.

Cigarette Smoke Induces Gefitinib Resistance in NSCLC Cells via ROS/Sirt3/SOD2 Pathway / 中国肺癌杂志

BACKGROUND@#Epidermal growth factor receptor (EGFR) gene mutations are the most common driver mutations in non-small cell lung cancer (NSCLC). To prolong the survival of the patients, EGFR tyrosine kinase inhibitors (TKIs) resistance in NSCLC is a major challenge that needs to be addressed urgently, and this study focuses on investigating the mechanism of cigarette smoke (CS) induced Gefitinib resistance in NSCLC.@*METHODS@#PC-9 and A549 cells were cultured in vitro and treated with 1 µmol/L Gefitinib for 4 h and 10% cigarette smoke extract (CSE) for 48 h. Western blot was used to detect Sirtuin 3 (Sirt3) and superoxide dismutase 2 (SOD2) protein expressions; DCFH-DA probe was used to detect intracellular reactive oxygen species (ROS); CCK-8 kit was used to detect cell activity, and EdU was used to detect cell proliferation ability. Sirt3 overexpression plasmid (OV-Sirt3) was transfected in PC-9 and A549 cells and treated with 1 µmol/L Gefitinib for 4 h and 10% CSE for 48 h after N-acetylcysteine (NAC) action. The expressions of Sirt3 and SOD2 were detected by Western blot; the ROS level in the cells was detected by DCFH-DA probe, and the cell activity was detected by CCK-8.@*RESULTS@#CSE induced an increase in the 50% inhibitory concentration (IC50) of both PC-9 and A549 cells to Gefitinib (P<0.01) and enhanced the proliferation of PC-9 and A549 cells, suggesting that CS induced Gefitinib resistance in NSCLC. ROS was involved in CSE-induced Gefitinib resistance (P<0.05). CSE induced low expressions of Sirt3 and SOD2 (P<0.01), and Sirt3/SOD2 was associated with poor prognosis in lung cancer patients (P<0.05). OV-Sirt3 in PC-9 and A549 cells reversed CSE-induced Gefitinib resistance (P<0.05) and significantly reduced ROS production. NAC reversed CSE-induced Gefitinib resistance in PC-9 and A549 cells (P<0.05).@*CONCLUSIONS@#The ROS/Sirt3/SOD2 pathway is involved in CS-induced Gefitinib resistance in NSCLC.

The protective effect and mechanism of N-acetylcysteine on acute kidney injury by up-regulating Sirtuin3 protein expression in septic mice / 中华急诊医学杂志

Objective:To explore the protective effect and mechanism of the antioxidant N-acetylcysteine (NAC) regulating silent information regulator 3 (Sirt3) on acute kidney injury (AKI) in septic mice.Methods:Male C57BL/6 mice were randomly ( random number) divided into the sham operation group (sham), cecal ligation and perforation group (CLP), CLP + NAC (50 mg/kg) and CLP + NAC (100 mg/kg) groups, with 10 mice in each group. The mice were sacrificed 24 h after CLP, and blood and kidney tissue samples were collected. HE staining was used to evaluate the pathological damage of the kidney tissue of mice in each group. ELISA was used to detect serum creatinine (Scr), urea nitrogen (BUN), kidney injury molecule 1 (KIM-1) and neutrophil gelatinase-associated apolipoprotein (NGAL) levels. Immunohistochemistry was used to detect the expression of Sirt3 protein in kidney tissue. RT-qPCR was used to detect the level of Sirt3 mRNA. Mitochondrial damage of renal tubular epithelial cells was observed under transmission electron microscope, and the mitochondrial density was calculated. Meanwhile, the levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) and malondialdehyde (MDA) in the renal cortex were also detected. Results:Compared with the sham group, in the CLP group, the pathological damage of renal tissue was significantly aggravated ( P<0.001), and the levels of renal function indicators (Scr, BUN, KIM-1 and NGAL) were all increased significantly (all P<0.001). The protein and mRNA expression of Sirt3 were all significantly decreased (all P<0.001), the mitochondrial structure damage of renal tubular epithelial cells was increased, and the mitochondrial density was significantly decreased ( P<0.001). The levels of antioxidant enzymes (SOD, GSH-Px and CAT) in the renal cortex were all significantly decreased (all P<0.001), while the lipid peroxide MDA was significantly increased ( P<0.001). Compared with the CLP group, the renal injury score and renal function indexes (Scr, BUN, KIM-1 and NGAL levels) in the 50 mg/kg NAC pretreatment group were decreased, and the levels of SOD, GSH-Px and CAT in renal tissue were increased, but the differences were not significant. However, pretreatment with 100 mg/kg NAC significantly reduced the pathological damage of kidney tissue caused by CLP ( P<0.001), and significantly decreased the levels of Scr, BUN, KIM-1 and NGAL (all P<0.001). The expression of Sirt3 protein [(50.20±2.79) vs.(20.00±0.75), P<0.001] and mRNA [(0.57±0.07) vs. (0.41±0.07), P<0.001] were all significantly increased. The mitochondrial structure of renal tubular epithelial cells was more stable, and the mitochondrial density was significantly increased [(0.60±0.05) vs. (0.43±0.06), P<0.001]. The levels of SOD [(67.37±3.79) U/mg vs. (21.09±0.89) U/mg, P<0.001], GSH-Px [(265.61±9.61) U/mg vs. (180.00±3.31) U/mg, P<0.001] and CAT [(8.58±0.65) U/mg vs. (5.19±0.58) U/mg, P<0.001] were all significantly increased, while the expression level of MDA was significantly reduced [(40.36 ±1.79) vs. (83.81 ±1.70), P<0.001]. Conclusions:NAC can significantly reduce renal pathological damage, improve renal function, maintain mitochondrial structure stability and reduce oxidative stress levels in septic mice by up-regulating Sirt3 protein expression, and has a significant protective effect on CLP-induced AKI.

Nicotinamide mononucleotide attenuates ischemia-reperfusion injury induced by donor liver from cardiac death through Sirt3 / 器官移植

Objective To evaluate the effect and mechanism of nicotinamide mononucleotide (NMN) on ischemia-reperfusion injury (IRI) induced by donor liver after cardiac death in rat models. Methods Rat models of orthotopic liver transplantation were established by "magnetic ring + double cuff" method. SD rats were randomly divided into the sham operation group (Sham group), orthotopic liver transplantation group (OLT group), NMN treatment + orthotopic liver transplantation group (NMN group), NMN+sirtuin-3 (Sirt3) inhibitor (3-TYP) + orthotopic liver transplantation group (NMN+3-TYP group), respectively. Pathological changes and hepatocyte apoptosis of the rats were observed in each group. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were determined. Superoxide dismutase (SOD) and malondialdehyde (MDA) contents in liver tissues were detected. The expression levels of Sirt3, microtubule-associated protein 1 light chain 3 (LC3)Ⅱ, PTEN-induced putative kinase 1 (PINK1), Parkin and translocase of the outer mitochondrial membrane 20 (TOMM20) in liver tissues were measured. Postoperative survival of the rats in each group was analyzed. Results Compared with the Sham group, serum ALT and AST levels were higher in the OLT group. Compared with the OLT group, the levels of ALT and AST were decreased in the NMN group. Compared with the NMN group, the levels of ALT and AST were increased in the NMN +3-TYP group (all P < 0.05). The liver tissue structure of rats in the Sham group was basically normal. In the OLT group, pathological changes, such as evident congestion, vacuolar degeneration and hepatocyte necrosis, were observed in the liver tissues. Compared with the Sham group, Suzuki score and apoptosis rate were higher in the OLT group. Suzuki score and apoptosis rate in the NMN group were lower than those in the OLT group. Suzuki score and apoptosis rate in the NMN+3-TYP group were higher compared with those in the NMN group (all P < 0.05). Compared with the Sham group, the SOD content was decreased, whereas the MDA content was increased in the OLT group. Compared with the OLT group, the SOD content was increased, whereas the MDA content was decreased in the NMN group. Compared with the NMN group, the SOD content was decreased, whereas the MDA content was increased in the NMN+3-TYP group (all P < 0.05). Compared with the Sham group, the relative expression levels of Sirt3 and TOMM20 proteins were down-regulated, whereas those of PINK1, Parkin and LC3Ⅱproteins were up-regulated in the OLT group. Compared with the OLT group, the relative expression levels of Sirt3, PINK1, Parkin and LC3Ⅱproteins were up-regulated, whereas that of TOMM20 protein was down-regulated in the NMN group. Compared with the NMN group, the relative expression levels of PINK1, Parkin and LC3Ⅱproteins were down-regulated, whereas that of TOMM20 protein was up-regulated in the NMN+3-TYP group (all P < 0.05). In the Sham group, the 7 d survival rate of rats was 100%, 50% in the OLT group, 75% in the NMN group and 58% in the NMN+3-TYP group, respectively. Conclusions NMN may enhance the antioxidative capacity of the liver, induce PINK1/Parkin-mediated mitochondrial autophagy, and alleviate IRI of the liver by up-regulating Sirt3, thereby playing a protective role in the donor liver after cardiac death.

Maternal hypothyroidism during pregnancy alters the function of the retinol-binding protein 4-mediated mitochondrial permeability conversion pore in the kidneys of offspring rats

OBJECTIVES To determine the role of the RBP4/PiC/SIRT3 signaling pathway in the opening of the mitochondria permeability transition pore (mPTP) in offspring rats with hypothyroidism during pregnancy. METHODS Sixty Sprague-Dawley (SD) rats were employed in this study. Pregnancy was deemed successful when a sperm was found in the uterus. After one week of pregnancy, offspring rats were divided into the following groups: overall hypothyroidism group (OH group), subclinical hypothyroidism group (SCH group), and normal control group (CON group). The establishment of the hypothyroidism model was confirmed when the serum thyroid stimulating hormone (TSH) levels were higher than normal value and TT4 level was within the normal range. The renal mitochondria of offspring rats were extracted on the 14th postnatal day (P14) and 35th postnatal day (P35). RESULTS At P14, no significant differences in the degree of mPTP opening and expression of phosphoric acid carrier vector (PiC) were detected between the rats in the OH group and the SCH group. However, the expression level of silent mating-type information regulation 3 homolog (SIRT3) was markedly reduced. Retinol-binding protein 4 (RBP4) expression increased in the rats from the OH group, relative to that in those from the SCH group. At P35, the degree of mPTP opening and the expression levels of PiC and RBP4 in the OH group were higher than those in the SCH group. However, SIRT3 expression in the OH group was lower than that observed in the SCH group. CONCLUSION RBP4 plays an important role in early renal mitochondrial damage and renal impairment in rats suffering from hypothyroidism during pregnancy. The RBP4/PiC/SIRT3 pathway is thus involved in the opening of the renal mPTP in offspring rats with hyperthyroidism.

Role of Sirt3 in lipopolysaccharide-induced abnormal mitochondrial dynamics in renal tubular epithelial cells / 中华肾脏病杂志

Objective:To observe the expression of sirtuin 3 (Sirt3) and mitochondrial damage-associated proteins in lipopolysaccharide (LPS)-induced acute kidney injury mouse model and renal tubular epithelial cells, and to explore the role of Sirt3 in LPS-induced abnormal mitochondrial dynamics in renal tubular epithelial cells.Methods:Eighteen specific pathogen free (SPF) male C57BL/6 mice were randomly assigned to control group, LPS 24 h group and LPS 48 h group. The control group was intraperitoneally injected with physiological saline (0.1 ml/10 g), and LPS 24 h group and LPS 48 h group were intraperitoneally injected with LPS (10 mg/kg) solution. Renal functional indexes of mice were analyzed by automatic biochemical analyzer. The pathological change of the kidney was observed by HE staining, and the expressions of dynamin-related protein-1 (Drp1), optic atrophy type 1 (Opa1) and Sirt3 were evaluated by Western blotting. Expression and distribution of Sirt3 in kidney was assessed by immunohistochemistry. Human renal tubular epithelial cells (HK-2) were exposed to 10 μg/ml LPS for 24 h, and the expression of Drp1, Opa1 and Sirt3 were detected by Western blotting. Cell apoptosis was assessed by Hoechst-33342 staining. After transfection to HK-2 cells with pcDNA3.1-Sirt3 recombinant plasmid, the expressions of Sirt3, Drp1, Opa1 and cell apoptosis were detected by the same methods as above.Results:(1) The levels of blood urea nitrogen and serum creatinine in LPS group were significantly higher than those in control group (both P<0.05), and the pathological changes of kidney were obvious. (2) Compared with the control group, the expression of mitochondrial fission-associated protein Drp1 in renal tissue of LPS group was significantly higher ( P<0.05), and the expression of mitochondrial fusion associated protein Opa1 was significantly lower ( P<0.05). (3) Compared with the control group, the expression of Sirt3 in LPS group was significantly lower ( P<0.05), and immunohistochemistry results showed that Sirt3 was mainly expressed in glomerular vascular endothelial cells and renal tubular epithelial cells. (4) In vitro, LPS stimulation induced increased Drp1 expression in HK-2 cells ( P<0.05), decreased Opa1 and Sirt3 expression (both P<0.05), and increased apoptosis ( P<0.05). (5) LPS-induced mitochondrial dynamics disturbance and apoptosis were alleviated by pcDNA3.1-Sirt3 recombinant plasmid transfection. Conclusions:LPS can induce down-regulation of Sirt3 expression and disturbance of mitochondrial dynamics, and Sirt3 may play a protective role in LPS-induced acute kidney injury by regulating mitochondrial dynamics.

Ginsenoside Rb1 Protects Human Umbilical Vein Endothelial Cells against High Glucose-Induced Mitochondria-Related Apoptosis through Activating SIRT3 Signalling Pathway / 中国结合医学杂志

OBJECTIVE@#To investigate whether ginsenoside Rb1 (Rb1) can protect human umbilical vein endothelial cells (HUVECs) against high glucose-induced apoptosis and examine the underlying mechanism.@*METHODS@#HUVECs were divided into 5 groups: control group (5.5 mmol/L glucose), high glucose (HG, 40 mmol/L) treatment group, Rb1 (50 µ mol/L) treatment group, Rb1 plus HG treatment group, and Rb1 and 3-(@*RESULTS@#Rb1 ameliorated survival in cells in which apoptosis was induced by high glucose (P<0.05 or P<0.01). Upon the addition of Rb1, mitochondrial and intracellular reactive oxygen species generation and malondialdehyde levels were decreased (P<0.01), while the activities of antioxidant enzymes were increased (P<0.05 or P<0.01). Rb1 preserved the mitochondrial membrane potential and reduced the release of Cyt-c from the mitochondria into the cytosol (P<0.01). In addition, Rb1 upregulated mitochondrial biogenesis-associated proteins (P<0.01). Notably, the cytoprotective effects of Rb1 were correlated with SIRT3 signalling pathway activation (P<0.01). The effect of Rb1 against high glucose-induced mitochondria-related apoptosis was restrained by 3-TYP (P<0.05 or P<0.01).@*CONCLUSION@#Rb1 could protect HUVECs from high glucose-induced apoptosis by promoting mitochondrial function and suppressing oxidative stress through the SIRT3 signalling pathway.

Metformin promotes autophagy in muscle cells exposed to palmitic acid through AMPK/SIRT3 pathway / 中华内分泌代谢杂志

Objective@#To investigate the effect of metformin on autophagy in muscle cells exposed to palmitic acid, and to explore its mechanism.@*Methods@#L6 rat myoblasts were incubated with palmitic acid at various concentrations(0.1, 0.2, 0.4, 0.6 mmol/L) and metformin(0.5, 1, 2, 5, 10 mmol/L) for 24 h. CCK8 method was used to detect the survival rate of muscle cells. After muscle cells were treated with palmitic acid and metformin for 24 h, mRNA and protein expressions of microtubule-associated protein11ight chain3(LC3Ⅱ), Beclin 1, p62, and silent mating type information regulation2 homolog-3(SIRT3) were detected by RT-PCR and Western blot, respectively. AMP-activated protein kinase(AMPK) phosphorylation level was detected by Western blot.@*Results@#Palmitic acid dose-dependently decreased the survival rate of muscle cells, which was attenuated by metformin at the concentration of 2 mmol/L. After muscle cells were incubated with 0.4 mmol/L palmitic acid and 2 mmol/L metformin for 24 h, palmitic acid significantly reduced the mRNA and protein expressions of LC3Ⅱ, Beclin1, and SIRT3 as well as phosphorylation level of AMPK(all P<0.05), and increased p62 mRNA and protein expressions(P<0.05). Those effects were all antagonized by metformin(all P<0.05).@*Conclusions@#Metformin treatment may promote the autophagy of muscle cells exposed to palmitic acid through AMPK/STRT3 pathway.

Moderate-intensity exercise allows enhanced protection against oxidative stress-induced cardiac dysfunction in spontaneously hypertensive rats

The progression of myocardial injury secondary to hypertension is a complex process related to a series of physiological and molecular factors including oxidative stress. This study aimed to investigate whether moderate-intensity exercise (MIE) could improve cardiac function and oxidative stress in spontaneously hypertensive rats (SHRs). Eight-week-old male SHRs and age-matched male Wistar-Kyoto rats were randomly assigned to exercise training (treadmill running at a speed of 20 m/min for 1 h continuously) or kept sedentary for 16 weeks. Cardiac function was monitored by polygraph; cardiac mitochondrial structure was observed by scanning electron microscope; tissue free radical production was measured using dihydroethidium staining. Expression levels of SIRT3 and SOD2 protein were measured by western blot, and cardiac antioxidants were assessed by assay kits. MIE improved the cardiac function of SHRs by decreasing left ventricular systolic pressure (LVSP), and first derivation of LVP (+LVdP/dtmax and −LVdP/dtmax). In addition, exercise-induced beneficial effects in SHRs were mediated by decreasing damage to myocardial mitochondrial morphology, decreasing production of reactive oxygen species, increasing glutathione level, decreasing oxidized glutathione level, increasing expression of SIRT3/SOD2, and increasing activity of superoxide dismutase. Exercise training in SHRs improved cardiac function by inhibiting hypertension-induced myocardial mitochondrial damage and attenuating oxidative stresses, offering new insights into prevention and treatment of hypertension.

Effect of Biling Qutong Prescription on SIRT3 Protein Expression and URAT1 mRNA in Skeletal Muscle of Diabetic Gout Rats / 中国实验方剂学杂志

Objective: To observe the effect of phlegm and blood stasis on the expressions of sirtuin 3(SIRT3)protein and urate transporter 1(URAT1) mRNA in skeletal muscle of diabetic rats with gout. Method: The 40 healthy rats, excepting the normal group, the remaining groups were fed with high-fat diet combined with low-dose streptozotocin solution (40 mg·kg-1) once a day, with blood glucose "16.7 mmol·L-1" as the criterion for the diabetes model. After 4 days, the 5% sodium urate solution was injected into the joint cavity once to induce the gout model. After the successful modeling, the Biling group (10 g·kg-1), the indomethacin group (5 mg·kg-1) and the pioglitazone group (10 mg·kg-1) continued to be administered for 21 days. The normal group and the model group were given the same amount of normal saline. The expression of SIRT3 protein in skeletal muscle tissue was determined by Western blot, URAT1 mRNA expression in bone tissue was detected by quantitative real-time fluorescence polymerase chain reaction(Real-time PCR),and blood was collected to measure blood glucose (GLU), blood uric acid (UA) and C-reactive protein (CRP). Result: Compared with the normal group, GLU, UA and CRP in the model group were significantly increased (PPPPPPPPConclusion: Biling Qutong prescription with effects in purging turbidity, detoxifying and dredging collaterals can significantly reduce the content of serum inflammatory factor CRP, significantly increase the protein expression of SIRT3 in skeletal muscle tissue of model rats, lower the content of URAT1 mRNA, reduce the blood glucose and blood uric acid levels in diabetic gout rats, and protect joints.

Platelet derived growth factor-BB regulates phenotype transformation of pulmonary artery smooth muscle cells via SIRT3 affecting glycolytic pathway / 中华心血管病杂志

Objective@#To investigate whether platelet-derived growth factor-BB (PDGF-BB) can regulate phenotypic transformation of pulmonary artery smooth muscle cells (PASMCs) via SIRT3 affecting glycolytic pathway.@*Methods@#The PASMCs were isolated from Sprague Dawley rats. PASMCs were divided into 3 groups by using 2-deoxyglucose (2-DG), an inhibitor of the glycolytic pathway: normal control group, PDGF-BB group(30 ng/ml) and PDGF-BB (30 ng/ml)+2-DG (10 mmol/L) group. In lentivirus-mediated overexpression assay, cells were divided into control group, PDGF-BB group(30 ng/ml), PDGF-BB+deacetylase sirtuin-3 (SIRT3) overexpression group and PDGF-BB+empty vector group. The expression levels of phenotype related index such as α-smooth muscle actin (α-SMA), smooth muscle myosin heavy chain (SM-MHC), calponin, vimentin were detected by qRT-PCR and Western blot. Meanwhile, the expression of α-SMA was detected by cellular immunofluorescence staining. EDU staining was used to detect the proliferation of PASMCs. The expression of SIRT3 was detected by Western blot. The expressions of glucose transporter 1 and aerobic glycolytic enzymes were detected by qRT-PCR and Western blot in lentivirus-mediated overexpression assay.@*Results@#(1) PDGF-BB affects PASMCs phenotypic transformation through glycolytic pathway: compared with normal control group, PDGF-BB significantly decreased the expressions of contractile phenotype markers such as α-SMA, SM-MHC, calponin mRNA and protein (all P<0.05), but it increased the expressions of the synthetic phenotype marker vimentin mRNA and protein (both P<0.05). Cellular immunofluorescence assay showed that PDGF-BB significantly decreased the number of α-SMA positive cells, while 2-DG reversed the process. (2) PDGF-BB promoted cell proliferation through glycolytic pathway: the proliferation of PASMCs was significantly higher in PDGF-BB group than in control group (P<0.05), and which could be significantly reduced by 2-DG (P<0.05). (3) PDGF-BB inhibited the expression of SIRT3 protein in PASMCs: the expression of SIRT3 protein in PDGF-BB group was lower than that in control group (P<0.05). (4) PDGF-BB affected glycolytic pathway through SIRT3:compared with the control group, PDGF-BB significantly increased the expression levels of glucose transporter 1 (Glut1), hexokinase 2 (HK2) and 6-phosphfructo-2-kinase 3 (PFKFB3) mRNA (all P<0.05), which was reserved by over-expression of SIRT3. There were no significant difference in mRNA expression levels between PDGF-BB group and PDGF-BB+empty vector group (P>0.05).Compared with the control group, PDGF-BB significantly increased the expression levels of Glut1, HK2 and PFKFB3 protein(all P<0.05), which was reserved by over-expression of SIRT3. There were no significant differences in protein expression levels between PDGF-BB group and PDGF-BB+empty vector group (all P>0.05).@*Conclusion@#PDGF-BB regulates phenotypic transformation of PASMCs via SIRT3 affecting glycolytic pathway.

Clinical significance of expression of MnSOD/SIRT3 in pernicious placenta previa combined with placenta implantation / 医学研究生学报

Objective Dangerous placenta previa(PPP) combined with placenta implantation seriously threatens maternal life safety. This paper aim to explore the changes of MnSOD and SIRT3,the expression of SIRT3 in maternal placenta PPP combined with placenta implantation, and the relationship between trophoblast invasion and placental implantation. Methods 90 cases with placenta implantation of pernicious placenta previa were collected from January 2014 to June 2018 in Anhui Maternal and Child Health Hospital. According to the depth of placental villus invading uterine myometrium, 30 cases of placenta adhesion, 30 cases of placental implantation, and 30 cases of placenta penetration, 30 cases of normal control group．Immunohistochemical SP and Western blot were used to detect the expression of MnSOD and SIRT3 in placental tissues of the study group and the control group, then compared and analyzed. Results Compared with the control group, the expression of MnSOD and SIRT3 in the placental implantation group were increased. With the increasing of placental implantation degree, the level of MnSOD and SIRT3 decreased significantly (P<0.05). Western blot showed that , the relative protein expressions of MnSOD/β-actin and SIRT3/β-actin in the control group were (0.39±0.05) and (0.41±0.08), which were higher than those in the adhesion group[(0.35±0.04), (0.32±0.02)], the implantion group[(0.28±0.02), (0.20±0.03)], and the penetration group[(0.23±0.01), (0.17±0.02)]. The difference was statistically significant(P<0.05). Conclusion The expressions of MnSOD and SIRT3 incytoplasm or nucleus of invasive trophoblasts and placental tissues of pregnant women with placental implantation is significantly decreased, both of which are involved in the occurrence and development of placental implantation, but the specific pathogenesis still needs to be further explored.

Ginsenoside Rb1 Attenuates Human Umbilical Vein Endothelial Cells Senescence Induced by High Glucose through Sirt3/SOD2 Pathway / 中山大学学报(医学科学版)

@#Abstract】 【Objective】To investigate the effect and mechanism of ginsenoside Rb1 attenuating human umbilical vein endothelial cells(HUVEC) senescence induced by high glucose through Sirt3/SOD2 pathway.【Methods】The senescence of HUVEC induced by high glucose(40 mmol/L)was assessed by senescence-associated β-galactosidase(SA-β-Gal)staining,and the expression of plasminogen activator inhibitor 1(PAI-1)and P16. Annexin V-FITC/PI was performed to measure apoptotic effect. The expression of sirtuins 3(Sirt3)and superoxide dismutase 2(SOD2)was detected by western blot. Meanwhile,the level of intracellular malondialdehyde(MDA)and the activity of SOD2 were measured.【Results】Treatment of HUVEC with high glucose for 24 hours induced premature senescence instead of apoptosis,as indicated by a larger proportion of the cells stained with SA-β-Gal and the up-regulated expression of PAI-1 and P16. Pretreatment of HUVEC with ginsenoside Rb1(40 μmol/L)could reverse endothelial cell senescence,as indicated by the reduced SA-β-Gal positive cells and the down-regulated expression of PAI-1 and P16. Furthermore,ginsenoside Rb1 pretreatment upregulated the protein expression of Sirt3 and SOD2,and eventually increased the activity of SOD2 and decreased the level of MDA.【Conclusion】Ginsenoside Rb1 could antagonize high glucose-induced premature senescence of HUVEC via Sirt3/SOD2 signaling pathway.

Recent advances in the role of SIRT3 in leukemia drug resistance / 上海交通大学学报（医学版）

Leukemia is a clonal malignant disease originating from abnormal hematopoietic stem cells or progenitor cells. The key issue of leukemia treatment is its drug-resistance. SIRT3 is the main mitochondrial NAD+ dependent deacetylase. It regulates enzymes and transcription factors of many metabolism pathways. SIRT3 acts both as oncogenic gene and tumor-suppressing gene in the oncogenesis of different cancers. Studies have shown that reactive oxygen species (ROS) level is closely related to drug resistance of cancer cells. ROS level is elevated in leukemia cells, thus affecting its drug resistance. SIRT3 can downregulate ROS level in many ways and enhance cell survival in the case of oxidative stress. Decreased deacetylase activity of SIRT3 makes leukemic cells more vulnerable to oxidative stress so that they are more sensitive to current chemotherapies. Through discovering the function of SIRT3 in leukemia cells, a chance of finding a new target for leukemia treatment can be found. This article reviews recent advances on the role of SIRT3 in leukemia drug resistance.

SIRT3:a potential target for CHF? / 中国药理学与毒理学杂志

Pathological cardiac hypertrophy is a maladaptive response in a variety of organic heart disease(OHD),which is characterized by mitochondrial dysfunction that results from disturbed energy metabolism. SIRT3, a mitochondria-localized sirtuin, regulates global mitochondrial lysine acetylation and preserves mitochondrial function. However, the mechanisms by which SIRT3 regulates cardiac hypertrophy remains to be further elucidated. In this study, we firstly demonstrated that expression of SIRT3 was decreased in AngiotensionⅡ(AngⅡ)-treated cardiomyocytes and in hearts of AngⅡ-induced cardiac hypertrophic mice. In addition, SIRT3 overexpression protected myocytes from hypertrophy, whereas SIRT3 silencing exacerbated Ang II-induced cardiomyocyte hypertrophy.In particular,SIRT3-KO mice exhibited significant cardiac hypertrophy. Mechanistically, we identified NMNAT3 (nicotinamide mononucleotide adenylyltransferase 3), the rate-limiting enzyme for mitochondrial NAD biosynthesis, as a new target and binding partner of SIRT3.Specifically,SIRT3 physically interacts with and deacety-lates NMNAT3,thereby enhancing the enzyme activity of NMNAT3 and contributing to SIRT3-mediated anti-hypertrophic effects.Moreover,NMNAT3 regulates the activity of SIRT3 via synthesis of mitochon-dria NAD.Taken together,these findings provide mechanistic insights into the negative regulatory role of SIRT3 in cardiac hypertrophy.Sirtuin 3(SIRT3),a mitochondrial deacetylase that may play an impor-tant role in regulating cardiac function and a potential target for CHF

Prognostic Significance of Sirtuins Expression in Papillary Thyroid Carcinoma

BACKGROUND AND OBJECTIVES: Sirtuins (SIRTs) play important roles in cellular and organismal homeostasis. They have distinct gene expression patterns in various cancers; however, the relationship between SIRT expression and the progression of thyroid cancer is unclear. We investigated the expression of SIRTs in patients with papillary thyroid carcinoma (PTC) and their role as biomarkers for predicting the aggressiveness of this disease. MATERIALS AND METHODS: We used immunohistochemical staining to evaluate the expression of SIRT1 and SIRT3 in tumor specimens from 270 patients with PTC. We also evaluated the potential association between SIRT expression and diverse clinicopathological features. RESULTS: High SIRT1 expression was negatively correlated with lymphovascular invasion, central lymph node metastasis, and lateral lymph node metastasis. Multivariate analyses revealed that high SIRT1 expression was a negative independent risk factor for lateral lymph node metastasis. By contrast, high SIRT3 expression was positively correlated with locoregional recurrence. Interestingly, when patients were grouped by tumor SIRT expression patterns, the group with low SIRT1 expression and high SIRT3 expression was correlated with more aggressive cancer phenotypes including central lymph node metastasis and lateral lymph node metastasis. CONCLUSION: Our results suggest that SIRTs play dual roles in tumor progression, and the combination of decreased SIRT1 expression and increased SIRT3 expression is significantly associated with a poor prognosis in patients with PTC.

Effect of sitagliptin on cardiomyocyte pyroptosis induced by type 2 diabe-tes mellitus and underlying mechanism / 中国病理生理杂志

AIM:To explore the effect of sitagliptin (SLT) on cardiomyocyte pyroptosis induced by type 2 dia-betes mellitus (T2DM) and the underlying mechanism. METHODS:The T2DM rat model was established by high-fat diet and intraperitoneal injection of streptozotocin (35 mg/kg). The model rats were treated with SLT at 3, 10 and 30 mg/kg and nicotinamide [NAM; an non-specific inhibitor of sirtuin (SIRT) family] at 500 mg/kg for 4 weeks. Fasting blood glu-cose was measured, and the tissue proteins were determined by the methods of Western blot and immunochemistry. RE-SULTS:Compared with control group, the pyroptosis of cardiomyocytes and NLRP3 expression were significantly induced, while the protein level of SIRT3 was downregulated by T2DM (P<0.05). SLT inhibited the pyrpotosis of diabetic rat car-diomyocytes, downregulated the expression of NLRP3, and upregulated the expression of SIRT3 in a dose-dependent man-ner (P<0.05). All the function of SLT (30 mg/kg) was reversed by the treatment with NAM (500 mg/kg). Compared with control group, the pyroptosis of cardiomyocytes and NLRP3 expression were significantly induced, while the protein level of SIRT3 was not regulated by NAM (500 mg/kg). CONCLUSION:SLT exerts the inhibitory effect on the pyropto-sis of cardiomyocytes induced by diabetes, and the mechanism is related to the SIRT3/NLRP3 signaling pathway.

Advances on Sirt3 in cardiovascular diseases and longevity / 基础医学与临床

Sirt3 is a kind of nicotinamide adenine dinucleotide (NAD+)-dependent deacetylases.Sirt3 is localized in mitochondria and has been involved in a wide range of mitochondrial biological functions, such as nutrient oxidation、ATP generation, reactive oxygen species (ROS) detoxification and mitochondrial homeostasis.Sirt3 plays an important role in the occurrence and development of cardiovascular diseases.Increased expression of Sirt3 gene has been associated with extended lifespan of humans.

Study on the correlation of SIRT3 with metabolic syndrome and myocardial hypertrophy / 中华内分泌代谢杂志

[Summary] SIRT3 is a member of the silent information regulator 2 ( Sir2) family, located in the inner mitochondrial membrane, with a strong effect of deacetylation. SIRT3 not only modulates energy metabolism, cell apoptosis, tumor growth, anti-aging etc. , but also plays an important role in the field of cardiovascular diseases. In this review, we summarize recent findings related to SIRT3 with metabolic syndrome and cardiac hypertrophy, to provide a theoretical basis for the further study on the potential role of SIRT3 in cardiovascular diseases.

HSP90 and SIRT3 expression in hepatocellular carcinoma and their effect on invasive capability of human hepatocellular carcinoma cells

Objective: To vexplore expression of HSP90, SIRT3 in liver cancer tissue and its effect on liver cancer cell invasion ability. Methods: Moderate expression of HSP90 in SMMC-7721, HepG2, LO2 and Hep-3B cell lines were screened, which was validated by RT-PCR. Over-expression of HSP90 cell line and lentivirus packaging HSP90-RNAi were established, which was validated by RT-PCR and western blot. The level of epithelial-mesenchymal transition (EMT) related gene was detected by western blot. The percentage of cancer stem cells was assayed by flow cytometry. Results: RT-PCR demonstrated the highest expression of HSP90 mRNA in SMMC-7721 cells, the lowest expression of HSP90 mRNA in Hep3B and LO2 and the moderate expression of HSP90 mRNA in Hep-G2. Therefore, HepG2 was selected as a follow-up experiment cell lines. Compared with the blank control group, expression of HSP90 in HSP overexpression group was increased obviously, and expression of HSP90 in HSP90 shRNA group was significantly decreased, which indicated successful establishment of HSP overexpression and shRNA group. The apoptotic cell in hsp-siRNA group was higher than the blank control group, while the HSP overexpression group showed opposite results. Western blot results showed transfection HSP promoted cells EMT transformation, up-regulated the level of E-cadherin, and down-regulated the level of Vimentin; meanwhile, shRNA group showed opposite results. Conclusions: Carcinoma HepG2 cell transfected high expression of HSP can promote the transformation of EMT, improve the expression of Vimentin, reduce the expression of E-cadherin, and inhibit apoptosis of cancer stem cells, which improve the invasive ability of cancer of the liver cells. While hsp-siRNA group presents opposite results. In summary, the expression of HSP is closely related to the occurrence, development and invasion of cancer of the liver tissue.