Alleviating effect of exenatide on ectopic lipid accumulation in skeletal muscle of ob/ob mice is independent on reducing body weight

AIM To investigate the alleviating effect of exenatide （Exe）， a glucagon-like peptide-1 （GLP-1） receptor agonist， on the ectopic lipid accumulation in skeletal muscle of ob/ob mice and its mechanism. METHODS Eight-week-old male ob/ob mice and their wild-type （WT） littermates were randomly divided into 3 groups， ob/ob group， ob/ob+Exe group and WT group， and treated with Exe at 24 nmol/kg or the same volume of saline intraperitoneally once daily for 4 weeks. The body weight， fasting blood glucose （FBG） and fat content were measured after the 4-week treatment. The oil red O staining and the quantification of triglyceride （TG） were performed on the skeletal muscle. The serum levels of TG， total cholesterol and free fatty acid （FFA） were also measured by ELISA. The expression levels of AMP-activated protein kinase （AMPK） and lipid metabolism-related proteins were determined by Western blot. Mouse myoblast C2C12 cells were used as an in vitro model to further investigate the effects of Exe. RESULTS As compared with the ob/ob mice treated with saline， 4-week Exe treatment did not reduce body weight， FBG， food intake and fat content in ob/ob mice （P>0.05）. However， serum FFA was decreased （P<0.05）. Oil red O staining and the quantification of TG showed that 4-week Exe treatment significantly attenuated the ectopic lipid accumulation in the skeletal muscle of ob/ob mice （P<0.05）. The results of Western blot showed that the levels of phosphorylated AMPK （p-AMPK） and lipolysis-related proteins were up-regulated， while the lipid synthesis-related proteins were down-regulated by Exe （P<0.05）. Treatment with Exe alleviated the lipid accumulation in the C2C12 cells induced by sodium palmate （P<0.05）， and the effects of Exe on the levels of p-AMPK and lipid metabolism-related proteins in the C2C12 cells were consistent with those in the ob/ob mice （P<0.05）. Treatment with Exe also up-regulated the protein expression of glucose transporter 4 and improved the ability of glucose uptake in the C2C12 cells （P<0.05）. CONCLUSION Short-term Exe treatment attenuates the ectopic lipid accumulation in skeletal muscle of ob/ob mice by up-regulating lipolysis-related proteins and down-regulating lipid synthesis-related proteins， which is independent on body weight loss.     

Effect of Tripterygium wilfordii multiglucoside on intestinal flora and immune function in IgA nephropathy rats based on C1GALT1/Cosmc pathway

AIM To investigate the effects of Triptergium wilfordii multiglucoside （TWM） on intestinal flora and immune function in IgA nephropathy （IgAN） rats based on core 1 β1，3-galactosyltransferase （C1GALT1） and its chaperone protein Cosmc （C1GALT1/Cosmc pathway）. METHODS The rat model of IgAN was established， and the animals were randomly divided into model group （IgAN group）， dexamethasone （Dex） group and TWM group. Normal rats served as normal control （NC） group. The levels of serum creatinine （SCr） and blood urea nitrogen （BUN）， 24-hour urinary total protein （24 h UTP） and the number of urinary red blood cells were measured by automatic biochemical analyzer. The levels of serum IgA1， and plasma tumor necrosis factor-α （TNF-α）， B-cell activating factor （Baff） and interleukin-17 （IL-17） were detected by ELISA. The level of galactose-deficient IgA1 （Gd-IgA1） was detected by Vicia villosa lectin affinity ELISA. The intestinal colony was cultured in selective bacterial medium. The ratio of CD4⁺ CD25⁺ regulatory T cells （Treg） to CD4⁺ T cells （Treg proportion） in peripheral blood mononuclear cells （PBMC） was detected by flow cytometry.Western blot was used to determine the protein expression of C1GALT1 and Cosmc in intestinal mucosa. RESULTS Compared with NC group， 24 h UTP， the number of urinary red blood cells， SCr， BUN， serum IgA1 and Gd-IgA1， the numbers of Enterobacteriaceae， Enterococcus and Bacteroides， and the levels of TNF-α， Baff and IL-17 in plasma in IgAN group were significantly increased （P<0.05）， while the numbers of Bifidobacteria and Lactobacilli， the Treg proportion in PBMC， and the protein expression levels of C1GALT1 and Cosmc in intestinal mucosa were significantly decreased （P<0.05）. Compared with IgAN group， 24 h UTP， the number of urinary red blood cells， SCr， BUN， serum IgA1 and Gd-IgA1， the numbers of Enterobacteriaceae， Enterococcus and Bacteroides， and the levels of TNF-α， Baff and IL-17 in plasma in Dex group and TWM group were significantly reduced （P<0.05）， and those in TWM group were lower than those in Dex group （P<0.05）. Moreover， the numbers of Bifidobacteria and Lactobacilli， the Treg proportion in PBMC， and the protein expression levels of C1GALT1 and Cosmc in intestinal mucosa were significantly elevated （P<0.05）， and those in TWM group were higher than those in Dex group （P<0.05）. CONCLUSION TWM reduces the abnormal glycosylation level of IgA in IgAN rats by promoting the activation of C1GALT1/Cosmc pathway， and attenuates the intestinal flora disorder and immune dysfunction in IgAN rats， thus exerting the therapeutic effect.     

CYP450 epoxygenase/EET pathway attenuates adipose inflammation of obese mice through HIF-1α

AIM To investigate the effects of cytochrome P450 （CYP450） epoxygenase/epoxyeicosatrienoic acid （EET） pathway on insulin resistance in obese mice， and to explore the possible mechanisms. METHODS High-fat diet-induced obesity model was established in C57BL/6Cnc mice， and the obese mice were randomly divided into 3 groups， including obesity group （treated with saline； n=10）， EET group （treated with 11，12-EET； n=10） and EET inhibitor 14，15-epoxyeicosa-5（Z）-enoic acid （EEZE） group （n=10）. Normal C57BL/6Cnc mice （n=10） treated with saline served as control. Protein expression of CYP2J2 （one of CYP450 epoxygenases） and hypoxia-inducible factor-1α （HIF-1α） was measured by Western blot. Vessel-like structure was detected by immunofluorescence staining. The serum levels of insulin， tumor necrosis factor-α （TNF-α）， interleukin （IL）-1β， IL-6 and monocyte chemoattractant protein-1 （MCP-1） were measured by ELISA. RESULTS In obese mice， homeostasis model assessment of insulin resistance （HOMA-IR） values were increased， the protein level of CYP2J2 was reduced， and the protein level of HIF-1α was increased in adipose tissues as compared with the controls （P<0.05）. The serum levels of MCP-1， IL-1β， IL-6 and TNF-α were also significantly increased in obese mice （P<0.05）. After treatment with 11， 12-EET， the HOMA-IR values were decreased compared with vehicle-treated obese mice， HIF-1α expression levels were decreased in the adipose tissue， and the serum levels of MCP-1， IL-1β， IL-6 and TNF-α were reduced （P<0.05）. Immunohistochemical results of adipose tissue from vehicle-treated obese mice showed a marked decrease in vessel-like structures （CD31-positive） compared with normal control mice （P<0.05）. EET treatment significantly increased the newly formed vessel-like structures in the visceral adipose tissues of obese mice as compared with vehicle-treated obese mice （P<0.05）. CONCLUSION High-fat diet-induced obesity and insulin resistance are closely related to the CYP450 pathway. Exogenous EETs effectively decrease obesity-induced insulin resistance possibly through pro-angiogenesis and attenuation of hypoxia and inflammation.     

Niflumic acid inhibits the proliferation,migration and invasion of glioma U87 cells

AIM To investigate the effect of niflumic acid （NFA） on human glioma U87 cells and to clarify the potential mechanism. METHODS The U87 cells were cultured in vitro and divided into blank control group， and 50， 100 and 200 μmol/L NFA groups. MTT assay was performed to determine the viability of cells in various groups. Migration and invasion abilities were measured by real-time cell analysis （RTCA）. RESULTS The results of MTT assay showed that compared with blank control group， the viability of U87 cells was increased after treatment with NFA for 12 h （P<0.05 or P<0.01）， while the viability was significantly decreased after treatment with NFA for 24 and 48 h （P<0.05 or P<0.01） in a concentration-dependent manner. The results of RTCA showed that compared with control group， the cell migration and invasion abilities were inhibited in 100 and 200 μmol/L NFA groups （P<0.05 or P<0.01） and the inhibitory effects were more obvious in 200 μmol/L NFA group （P<0.01）. CONCLUSION NFA inhibits the viability， migration and invasion of human glioma U87 cells.     

Effect of lncRNA FEZF1-AS1 on viability and apoptosis of LPS-induced vascular endothelial cells by regulating miR-363-3p expression

AIM To investigate the mechanism of long noncoding RNA （lncRNA） FEZF1-AS1 regulating microRNA-363-3p （miR-363-3p） on the viability and apoptosis of lipopolysaocharide （LPS）-induced vascular endothelial cells. METHODS Human umbilical vein endothelial cells （HUVECs） were cultured in vitro. pcDNA-NC， pcDNA-FEZF1-AS1， anti-miR-NC， anti-miR-363-3p， miR-NC and miR-363-3p mimics were transfected into the HUVECs and LPS stimulation was applied for 24 h. RT-qPCR was used to detect the expression of FEZF1-AS1 and miR-363-3p. The cell viability was measured by MTT assay. The apoptotic rate was analyzed by flow cytometry. The dual-luciferase reporter experiment was used to verify the targeted regulation of FEZF1-AS1 and miR-363-3p. Western blot was used to determined the expression of cyclin D1， Ki67 and cleaved caspase-3. RESULTS Compared with control group， the expression level of FEZF1-AS1 in LPS group was significantly reduced （P<0.05）， and the expression level of miR-363-3p was significantly increased （P<0.05）. Compared with pcDNA-NC+LPS group， the cell viability in pcDNA-FEZF1-AS1+LPS group was significantly increased （P<0.05）， the apoptotic rate was significantly reduced （P<0.05）， the protein levels of cyclin D1 and Ki67 were significantly increased （P<0.05）， and the protein level of cleaved caspase-3 was significantly reduced （P<0.05）. Compared with anti-miR-NC+LPS group， the cell viability in anti-miR-363-3p+LPS group was significantly increased （P<0.05）， the apoptotic rate was significantly reduced （P<0.05）， the protein levels of cyclin D1 and Ki67 were significantly increased （P<0.05）， and the protein level of cleaved caspase-3 was significantly reduced （P<0.05）. Dual-luciferase reporter experiment confirmed that FEZF1-AS1 targeted miR-363-3p. Compared with miR-NC+pcDNA-FEZF1-AS1+LPS group， the cell viability in miR-363-3p+pcDNA-FEZF1-AS1+LPS group was significantly reduced （P<0.05）， the apoptotic rate was significantly increased （P<0.05）， the protein levels of cyclin D1 and Ki67 were significantly reduced （P<0.05）， and the protein level of cleaved caspase-3 was significantly increased （P<0.05）. CONCLUSION Over-expression of FEZF1-AS1 promotes the viability and inhibits apoptosis of LPS induced vascular endothelial cells by inhibiting the expression of miR-363-3p.     

Curcumin inhibits Porphyromonas gingivalis LPS-induced inflammatory response in human gingival fibroblasts by up-regulating miR-124

AIM To investigate the effects of curcumin （Cur） on the inflammatory response of human gingival fibroblasts （HGFs） induced by Porphyromonas gingivalis （Pg） lipopolysaccharide （LPS） and the role of microRNA-124 （miR-124） in this process. METHODS The HGFs were divided into control group， LPS group （10 mg/L LPS） and LPS+Cur （20， 40 and 80 μmol/L） groups （10 mg/L LPS+corresponding dose of Cur）. After treatment for 24 h， CCK-8 assay was used to measure the cell viability. ELISA was used to measure the levels of interleukin-1β （IL-1β） and tumor necrosis factor-α （TNF-α） in the supernatant. The level of miR-124 in the cells was detected by RT-qPCR. The protein levels of nuclear factor kappa B （NF-κB） p-p65 in cytoplasm and nucleus were determined by Western blot， and the nuclear translocation of NF-κB p-p65 was evaluated by laser confocal microscopy. After transfection with mimic-NC or miR-124 mimic， the expression of miR-124 and NF-κB p-p65 protein in the cytoplasm and nucleus of the cells were also detected. RESULTS The cell viability， the level of miR-124 in the cells and NF-κB p-p65 protein level in cytoplasm of LPS group were lower than those in control group （P<0.05）， while the levels of IL-1β and TNF-α in the supernatant and NF-κB p-p65 protein level in the nucleus were higher than those in control group （P<0.05）. The cell viability， the level of miR-124 in cells and NF-κB p-p65 protein level in the cytoplasm of LPS+Cur （40 and 80 μmol/L） groups were higher than those in LPS group （P<0.05）， while the level of TNF-α in the supernatant and NF-κB p-p65 protein level in the nucleus were lower than those in LPS group （P<0.05）. The level of IL-1β in the supernatant of LPS+80 μmol/L Cur group was lower than that in LPS group （P<0.05）. The levels of miR-124 and NF-κB p-p65 protein level in the cytoplasm of miR-124 mimic group were higher than those in LPS group and mimic-NC group （P<0.05）， while the level of NF-κB p-p65 proteinlevel in the nucleus was lower than that in LPS group and mimic-NC group （P<0.05）. CONCLUSION Curcumin inhibits the inflammatory response of HGFs induced by Pg LPS， which may be achieved by up-regulating miR-124 and then inhibiting the nuclear translocation of NF-κB p-p65.     

Expression of histone chaperone ASF1B in prostate cancer cells and its effect on cell viability in vitro

AIM To investigate the expression of histone chaperone anti-silencing function 1B （ASF1B） in prostate cancer cells and its effect on cell viability in vitro. METHODS Human prostate cancer PC-3 cells were used， and knockdown of ASF1B was conducted by small interfering RNA （siRNA） transfection into the cells. The cells were divided into control group， siRNA negative control vector （mock） group and siRNA-ASF1B group. The viability of the PC-3 cells treated with ASF1B-siRNA for 12， 24 and 48 h was measured by MTT assay. Flow cytometry was used to analyze cell apoptosis and cell cycle distribution. The mRNA expression of apoptosis-related molecules was detected by RT-qPCR， and the expression levels of MAPK/JNK/ERK signaling pathway-related proteins were determined by Western blot. RESULTS The protein level of ASF1B in the normal cells （benign prostatic hyperplasia） was significantly lower than that in the PC-3 cells （P<0.01）. Compared with control group and mock group， the protein expression level of ASF1B in the PC-3 cells transfected with siRNA-ASF1B plasmid and the viability of the PC-3 cells were significantly decreased （P<0.01）. The apoptotic rate of the PC-3 cells transfected with siRNA-ASF1B plasmid was significantly higher than that in control group （P<0.01）， and the cell cycle was arrested at G₁ phase. The mRNA levels of p53， caspase-3， Bax and PARP-1 in the PC-3 cells transfected with siRNA-ASF1B plasmid were up-regulated compared with those in control group and Mack group （P<0.01）. In addition， the protein levels of MAP2K4 and p-JNK in the PC-3 cells in siRNA-ASF1B group were significantly higher than those in mock group （P<0.01）， while the protein level of p-ERK was significantly lower than that in mock group （P<0.01）. CONCLUSION ASF1B silencing induces G₁ arrest and promotes apoptosis of PC-3 cells. Activating MAPK/JNK/ERK signaling pathway may be a possible contributor to the anti-prostate cancer effect of siRNA-ASF1B.     

Effects of oxidative stress and inflammatory response on kidney injury in mice with hyperthyroidism

AIM To explore the effects of oxidative stress and inflammatory response on kidney injury induced by hyperthyroidism in mice. METHODS Forty male Kunming mice were randomly divided into control group （n=20） and L-thyroxine （T4） group （n=20）. The mice in T4 group were intraperitoneally injected with T4 diluent at a dose of 1 mg/kg to induce hyperthyroidism， and those in control group were injected with normal saline of the same volume. After 7 weeks， the mice were weighed and dissected， the kidneys were removed and weighed， and the length of tibia was also measured. The activity of superoxide dismutase （SOD） and the content of malondialdehyde （MDA） in the kidney tissues were detected. The pathological changes of the kidney tissues were observed by HE staining. The levels of 4-hydroxynonenal （4-HNE）-modified proteins， interleukin-1 receptor-associated kinase 1 （IRAK1） and tumor necrosis factor receptor-related factor 6 （TRAF6） were determined by Western blot and immunohistochemistry. RESULTS Compared with control group， the body weight of the mice was decreased， while the kidney size and weight were increased significantly in T4 group. In addition， the ratios of kidney weight/body weight and kidney weight/tibia length were also increased （P<0.05）. In T4 group， the renal tubules were enlarged， and the epithelial cells of renal tubules were swollen and exfoliated， with vacuolar degeneration. Furthermore， reduced SOD activity， and increased MDA content and 4-HNE-modified proteins were found in T4 group， all of which were related to oxidative stress （P<0.05）. The levels of inflammation-related proteins IRAK1 and TRAF6 were significantly increased in T4 group （P<0.05）. CONCLUSION Excessive T4 may lead to kidney hypertrophy and injury in mice， and the mechanism may be related to oxidative stress and inflammatory response.     

Effects of eosinophils deletion on sPLA2-X in bronchial asthma model mice

AIM To investigate the association between soluble phospholipase A2-X（sPLA2-X） and eosinophils in bronchial asthma， and to provide new insight and strategies for the treatment of bronchial asthma. METHODS Female Babl/c mice （n=48） of SPF grade and 6~8 weeks old were divided into 4 groups （with 12 in each group： healthy control group，asthma control group， eosinophil deletion group， and asthma /eosinophil deletion isotype control group）. The mouse model of bronchial asthma was constructed. The mice in healthy control group were intraperitoneally injected with saline on days 0， 7， and 14. The mice in other groups were intraperitoneally injected with 50 μg OVA and 2 mg aluminum hydroxide gel（soluble in 200 μL saline.On the 21st d and 26 th d， eosinophil deletion antibody （anti-CCR3） and isotype control were intraperitoneally injected and intranasally respectively， and then the lungs function test was conducted within 48 h after the end of nebulization.Half of the mice in each group were subjected to whole lung lavage， the remaining half were used for lung tissue section with HE staining， the whole blood was used to measure serum IgE， the supernatant of broncho alveolar lavage fluid （BALF） was used to measure cytokines， and total number of cells in the bronchoalveolar lavage fluid was analyzed for cell classification and flow cytometry. RESULTS （1）Compared with asthma control group，the airway and alveolar inflammatory responses in asthma/eosinophil deletion group was significantly alleviated.（2） Compared with asthma control group， anti-CCR3 successfully deleted eosinophils， and the percentage of eosinophils in bronchoalveolar lavage fluid in asthma/eosinophil deletion group was significantly reduced （P<0.05）.（3） The airway hyperresponsiveness in asthma/eosinophil deletion group was significantly decreased as compared with asthma control group（P<0.05）.（4） The levels of sPLA2-X in the serum and BALF was significantly reduced in asthma/eosinophil deletion group as compared with asthma control group（P<0.05）.（5）Compared with asthma control group，the levels of IL-4， IL-5， and IL-13 in the BALF of the mice in asthma/eosinophil deletion group were significantly reduced， and the serum level of IgE was also decreased （P<0.05）. CONCLUSION Eosinophils in bronchial asthma are importantly associated with sPLA2-X.     

Relationships between lncRNA HOTAIR/H19 SNPs and genetic susceptibility to gastric carcinoma/EBV-related gastric carcinoma

AIM To investigate the potential associations between the single nucleotide polymorphisms （SNPs） of long noncoding RNA （lncRNA） H19/HOTAIR and the susceptibility to gastric carcinoma， especially to Epstein-Barr virus （EBV）-associated gastric carcinoma （EBVaGC）. METHODS Peripheral blood samples from 65 cases of EBV-negative gastric carcinoma （EBVnGC）， 50 cases of EBVaGC and 115 cases of healthy people were collected. A total of 4 TagSNPs， H19 rs3024270 and rs3741219， as well as HOTAIR rs4759314 and rs874945， were selected. The Taq-Man MGB allele typing kit was used to detect the genotype of each SNP locus， and the experimental results were statistically analyzed. RESULTS （1） There were significant differences of both genotypic and allelic frequencies at H19 rs3024270 locus between gastric carcinoma group and control group （P<0.05）. Individuals carrying the G allele at H19 rs3024270 locus had significantly low risk of gastric carcinoma （P<0.01）， indicating that the G allele was protective. （2） People with the GG genotype at HOTAIR rs4759314 locus had significantly high risk of gastric carcinoma （P<0.05）. Carrying the G allele increased the risk of gastric carcinoma， which indicated that the risk gene for gastric carcinoma might be the G allele. （3） No significant difference of the genotypic and allelic frequencies at H19 rs3741219 and HOTAIR rs874945 loci between gastric carcinoma group and control group was observed （P>0.05）.（4） The G allele frequency at HOTAIR rs4759314 locus in EBVaGC group was significantly higher than that in EBVnGC group. However， no difference of the other 3 SNPs was found between EBVaGC group and EBVnGC group （P>0.05）. CONCLUSION The SNPs at H19 rs3024270 and HOTAIR rs4759314 loci are related to the risk of gastric carcinoma， but not significantly related to the risk of EBVaGC.     

Cyanidin attenuates pressure overload-induced cardiac remodeling in mice via mitochondrial fusion enhancement

AIM To investigate the effect of cyanidin （Cyn） on pressure overload-induced cardiac remodeling and the underlying mechanism. METHODS Six-week-old male C57BL/6 mice （n=120） were divided into 4 groups： sham group （n=20）, sham+Cyn group （n=20）, transverse aortic constriction （TAC） group （n=40） and TAC+Cyn group （n=40）. The model of cardiac chronic pressure overload was induced by TAC, and the first day of TAC was defined as day 0. The animals in sham+Cyn group and TAC+Cyn group were treated with Cyn dissolved in DMSO and normal saline （5 mg·kg^-1·d^-1） for 5 d before TAC, while the animals in sham group and TAC group were treated with the same amount of DMSO and normal saline. Four weeks after TAC, the survival rate of the animals in each group was analyzed, the heart function of the mice was measured by ultrasound echocardiography, and the heart weight/body weight and lung weight/body weight were calculated. The cross-sectional area of the cardiomyocytes was measured by wheat germ agglutinin staining and hematoxylin-eosin staining. The degree of cardiac oxidative stress was evaluated by dihydroethidium staining and measurement of superoxide dismutase （SOD） and malondialdehyde （MDA） levels. The cardiomyocyte apoptosis was detected by TUNEL method. The mRNA expression levels of atrial natriuretic peptide （ANP）, brain natriuretic peptide （BNP） and β-myosin heavy chain （β-MHC） were detected by RT-qPCR, and the protein expression levels of Bax, Bcl-2, optic atrophy protein 1 （OPA1） and dynamin-related protein 1 （Drp1） were determined by Western blot. The mitochondrial morphological changes were observed by transmission electron microscopy. RESULTS Compared with TAC group, the survival rate of the mice in TAC+Cyn group was significantly increased （P<0.05）, the myocardial apoptosis, the cross-sectional area of myocardial cells, the heart weight/body weight, the lung weight/body weight, the level of reactive oxygen species and the MDA content were decreased （P<0.05）, and the SOD was activated （P<0.05）. M-mode ultrasound tests showed that Cyn treatment significantly increased left ventricular ejection fraction and left ventricular fractional shortening in the mice after TAC （P<0.05）, while left ventricular end-diastolic diameter and left ventricular posterior wall thickness in diastole were reduced （P<0.05）. Transmission electron microscopic observation showed that the number of myocardial mitochondria was increased and the mitochondrial area was decreased after TAC （P<0.05）, while treatment with Cyn increased the area of myocardial mitochondria and decreased the mitochondrial number （P<0.05）. Compared with sham group, the protein level of OPA1 in TAC group was significantly reduced （P<0.05）, while treatment with Cyn significantly increased the protein level of OPA1. CONCLUSION Cyanidin significantly increases the survival rate, improves the cardiac function and attenuates the cardiac remodeling of the mice after TAC. The mechanism may be related to the inhibition of myocardial mitochondrial OPA1 cleavage and the promotion of mitochondrial fusion.     

Effect of abnormal expression of PDK4 on glycolysis and proliferation in prostate cancer cells

AIM To investigate the expression of pyruvate dehydrogenase kinase 4 （PDK4） in prostate cancer tissue and its effect on glycolysis and growth of prostate cancer cells. METHODS Immunohistochemistry was used to compare the expression differences of PDK4 protein in benign prostatic hyperplasia （BPH） and prostate cancer tissues. The expression levels of PDK4 in normal prostatic epithelial cells （RWPE-1） and different prostate cancer cell lines （PC3， LNCaP， DU145 and C4-2） were detected by RT-qPCR and Western blot. Recombinant plasmid carrying PDK4-shRNA was constructed， and the expression of PDK4 in prostate cancer PC3 cells was down-regulated by transfection with PDK4-shRNA. The changes in glycolysis level of PC3 cells before and after transfection were determined by cell glycolysis kit， and the effects of PDK4 on the viability and cell cycle distribution of PC3 cells were detected by CCK-8 assay and flow cytometry. RESULTS In prostate cancer tissues， the expression level of PDK4 protein was significantly higher than that in BPH tissues （P<0.05）， and the analysis of immunohistochemical score showed that prostate cancer tissues with high Gleason score displayed significantly higher PDK4 expression than those with low Gleason score （P<0.05）. Compared with normal prostatic epithelial cells， RT-qPCR and Western blot results indicated that the expression level of PDK4 was also significantly increased in prostate cancer cell lines （P<0.05）. In addition， CCK-8 assay results showed that the viability of prostate cancer PC3 cells was significantly decreased after knockdown of PDK4 expression （P<0.05）. The results of flow cytometry demonstrated that knockdown of PDK4 expression in PC3 cells resulted in a notable increase in G₀/G₁ phase arrest （P<0.05）. CONCLUSION PDK4 is highly expressed in prostate cancer tissues and cell lines， and significantly increases in prostate cancer with high Gleason score. In addition， down-regulation of PDK4 expression significantly inhibits glycolysis and growth of prostate cancer cells， resulting in cell cycle arrest at G₀/G₁ phase.     

Scutellarin affects LPS-induced oxidative stress and apoptosis of glomerular epithelial cells by up-regulating miR-7-5p

AIM To investigate the effect of scutellarin （SCU） on oxidative stress and apoptosis induced by lipopolysaccharide （LPS） in human glomerular epithelial cells and its mechanism. METHODS Human glomerular epithelial cells were cultured in vitro， and were treated with LPS （1.0 mg/L） to establish a cell injury model. The cells were divided into normal control （NC） group， LPS group， NC+SCU group， LPS+SCU group， LPS+miR-NC group， LPS+microRNA-7-5p （miR-7-5p） group， LPS+SCU+anti-miR-NC group and LPS+SCU+anti-miR-7-5p group. Cell viability was detected by CCK-8 assay. Apoptosis was detected by flow cytometry. The intracellular malondialdehyde （MDA） content and superoxide dismutase （SOD） activity， and lactate dehydrogenase （LDH） activity in the cell culture supernatant were determined by kit. RT-qPCR was used to detect the expression level of miR-7-5p. RESULTS Compared with NC group， the cell viability， miR-7-5p expression and SOD activity in LPS group were significantly reduced， and the apoptotic rate， MDA content and LDH activity were significantly increased （P<0.05）. Compared with LPS group， the cell viability， miR-7-5p expression and SOD activity in LPS+SCU group were significantly increased， and the apoptotic rate， MDA content and LDH activity were significantly reduced （P<0.05）. Compared with LPS+miR-NC group， the cell viability and SOD activity in LPS+miR-7-5p group were significantly increased， and the apoptotic rate， MDA content and LDH activity were significantly reduced （P<0.05）. Compared with LPS+SCU+anti-miR-NC group， the cell viability and SOD activity in LPS+SCU+anti-miR-7-5p group were significantly reduced， and the apoptotic rate， MDA content and LDH activity were significantly increased （P<0.05）. CONCLUSION Scutellarin inhibits LPS-induced oxidative stress damage and apoptosis in glomerular epithelial cells via up-regulating miR-7-5p expression.     

Activity of NLRP3 inflammasome in MRSA pneumonia secondary to influenza A virus infection in mice

AIM To evaluate the activity of NLRP3 inflammasome in methicillin-resistant Staphylococcus aureus （MRSA） pneumonia secondary to influenza A virus （IAV） HIN1 in mice. METHODS Pneumonia model caused by intranasal inoculation with only MRSA for 24 h （MRSA group） and with MRSA for 24 h secondary to IAV H1N1 infection for 6 d in advance （H1N1+MRSA group）in C57BL/6 mice were established.The mRNA expression of NLRP3， caspase-1 and interleukin-1β （IL-1β） in lung tissues was detected by RT-qPCR. The protein levels of NLRP3 and caspase-1 in the lung tissues were determined by Western blot. The serum concentration of IL-1β was measured by ELISA. The pathological changes of the lung tissues were examined. The correlation between rate of weight loss during infection and serum concentration of IL-1β was investigated. RESULTS In MRSA group， the mRNA levels and relative protein expression levels of NLRP3 and caspase-1 showed no difference compared with control group （P>0.05）， while the mRNA expression of IL-1β and the serum concentration of IL-1β were significantly higher than those in control group （P<0.01）. In H1N1+MRSA group， the mRNA levels and relative protein expression levels of NLRP3 and caspase-1 were significantly higher than those in control group， as well as higher than those in MRSA group （P<0.01）， the mRNA level and serum concentration of IL-1β were significantly higher than those in control group but lower than those in MRSA group （P<0.01）. The pathological observation of the lung in MRSA group showed inflammatory responses， and severer pneumonia in H1N1+MRSA group was found. The rate of weight loss in the mice of MRSA group and H1N1+MRSA group was negatively correlated with the serum concentration of IL-1β. CONCLUSION IL-1β expression induced by MRSA infection is in a NLRP3 inflammasome independent manner. It also suggests that IAV H1N1 infection in advance down regulates the expression of IL-1β in secondary infection with MRSA， which may contribute to the mechanism of MRSA pneumonia secondary to IAV infection.     

Effect of 27nt-miRNA on apoptosis of human umbilical vein endothelial cells induced by oxidized low-density lipoprotein

AIM To investigate the effect of 27nt-miRNA （27nt-miR） on apoptosis of human umbilical vein endothelial cells （HUVECs） induced by oxidized low-density lipoprotein （Ox-LDL） and its underlying mechanism. METHODS HUVECs were cultured in vitro and grouped as below： normal control group， Ox-LDL group， 27nt-miR+Ox-LDL group， anti-27nt-miR+Ox-LDL group and negative control+Ox-LDL group. The cells in Ox-LDL group were treated with Ox-LDL at 40 mg/L for 48 h， while those in normal control group were untreated but cultured normally. The cells in 27nt-miR+Ox-LDL group， anti-27nt-miR+Ox-LDL group and negative control+Ox-LDL group were transfected with their corresponding lentiviral vectors under the same procedure， followed by treatment with Ox-LDL at 40 mg/L for 48 h to induce apoptosis. The cell viability was measured by CCK-8 assay. The migration capacity was detected by scratch assay. The caspase-3 activity was measured by caspase-3 activity assay kit. The apoptotic rate was analyzed by Hoechst 33258 and flow cytometry. The mRNA and protein expression levels of Bcl-2， Bax and caspase-3 were determined by RT-qPCR and Western blot. RESUITS： Compared with negative control+Ox-LDL group， the cell viability and migration ability were significantly decreased by over-expression of 27nt-miR in the HUVECs （P<0.05）， while the activity of caspase-3 and apoptosis induced by Ox-LDL were significantly increased （P<0.05）. Furthermore， the mRNA and protein expression levels of Bax and caspase-3 were significantly up-regulated （P<0.05）， and the mRNA and protein expression level of Bcl-2 was down-regulated in 27nt-miR+Ox-LDL group （P<0.05）. Meanwhile， all the above indexes showed an opposite tendency in anti-27nt-miR+Ox-LDL group. CONCLUSION 27nt-miR promotes Ox-LDL-induced apoptosis and inhibits the viability and migration of HUVECs in vitro， possibly through regulating the expression of apoptotic/anti-apoptotic proteins such as Bax，caspase-3 and Bcl-2.     

Effect of continuous renal replacement therapy on mRNA expression of autophagy-related molecules and prognosis in patients with acute kidney injury

AIM To explore the effect of continuous renal replacement therapy （CRRT） on mRNA expression of autophagy-related molecules and the prognosis in the patients with acute kidney injury （AKI）. METHODS A total of 174 patients from our hospital who were diagnosed to have AKI and underwent CRRT between February 2015 and March 2018 were involved in this study. The plasma levels of interleukin-1β （IL-1β） and interleukin-6 （IL-6）， the serum creatinine （SCr） level， and the mRNA expression levels of autophagy-related molecules， including microtubule-associated protein 1 light chain 3-II （LC3-II）， autophagy-related protein 5 （Atg5） and beclin-1， in the monocytes from peripheral blood were compared before and after CRRT. According to the survival of AKI patients after 4 weeks of CRRT， the enrolled patients were divided into death group （n=43） and survival group （n=131）， and the mRNA expression levels of the above molecules were compared between the 2 groups. RESULTS After CRRT treatment， the plasma levels of IL-1β and IL-6， the level of SCr， and the mRNA expression levels of LC3-II， Atg5 and beclin-1 in the monocytes were significantly lower than those before CRRT treatment （P<0.05）. The mRNA expression levels of LC3-II， Atg5 and beclin-1 in death group were significantly higher than those in survival group （P<0.05）. The positive correlation between SCr and IL-1β， IL-6， LC3-II or beclin-1 was observed （P<0.05）， and no correlation between SCr and Atg5 was found （P>0.05）. CONCLUSION CRRT decreases the mRNA expression levels of autophagy-related molecules in the patients with AKI and reduces the autophagy activity， which is protective for the patients. These autophagy-related molecules may be applied as a potential markers to predict the prognosis of CRRT.     

草莓白化相关病毒中国分离物全基因组分析

草莓白化相关病毒(strawberrypallidosis-associatedvirus,SPa V)属于长线形病毒科(Closteroviridae)毛形病毒属(Crinivirus),可引起草莓病害,2017年在中国首次报道。采用高通量测序、RACE和RT-PCR技术获得了SPa V中国分离物(FJ)的基因组全长。该病毒含有两条正单链基因组RNA1和RNA2。RNA1全长8 048 nt,5′和3′非编码区序列分别为264和197 nt,含有3个开放阅读框(ORF),分别编码ORF 1a/1b融合蛋白和p9蛋白。RNA2全长7 977 nt,5′和3′非编码区序列分别为248和186 nt,含有8个开放阅读框(ORF),分别编码HSP70h、CPh、CP、CPm、p7、p6、p9和p28等8个蛋白。RNA1和RNA2与美国M1分离物分别具有98.5%和99.0%的核苷酸一致性;系统发育分析结果表明,SPa V中国分离物(FJ)单独处在一个分支。对SPa V来源的小RNA的分析表明,来源于SPa V的小RAN长度以21和22 nt为主。     

Differential expression of nesfatin-1 in intestinal tissues of premature infants with necrotizing enterocolitis and and its mechanism

AIM To analyze the expression of nesfatin-1 in intestinal tissues of premature infants with necrotizing enterocolitis （NEC）， and to explore the effect of nesfatin-1 on lipopolysacharide （LPS）-induced enterocytes and its mechanism. METHODS The intestinal tissues were obtained from infants who underwent intestinal surgery for NEC in our hospital from 2017 to 2019. The mRNA expression of nesfatin-1 in the tissue samples of NEC were evaluated by RT-qPCR. Human fetal normal colon epithelial HCoEpiC cells and human colon cancer Caco-2 cells were used as research objects. The effect of nesfatin-1 on the secretion of cytokines was measured by ELISA. Western blot was used to analyze the protein expression of nesfatin-1 and Toll-like receptor 4 （TLR4）， NLRP3， AIM2， caspase-1 and ASC， and co-immunoprecipitation assay were conducted to explore the relation between nesfatin-1 and TLR4. RESULTS The expression of nesfatin-1 in NEC preterm infants was significantly lower than that in the healthy group （P<0.01）. Compared with control group， the expression of nesfatin-1 in HCo Epic cells and HT-29 cells induced by LPS was decreased （P<0.01）， while the transfection of nesfatin-1 reversed the stimulation of LPS， and the over-expression of nesfatin-1 decreased the levels of tumor necrosis factor-α （TNF-α） and interleukin-6 （IL-6）， and increased the level of IL-10 （P<0.05）. In addition， nesfatin-1 over-expression inhibited the expression of NLRP3， AIM2， caspase-1 and ASC. The expression of TLR4 in NEC tissue samples was significantly higher than that in healthy infants （P<0.05）. Pearson correlation analysis showed that there was a significant negative correlation between nesfatin-1 and TLR4 （r=-0.816， P<0.01）. TLR4 was found to co-precipitate with nesfatin-1. CONCLUSION Nesfatin-1 protects intestinal cells from LPS induced inflammation by targeting TLR4， which may be a potential target of anti-NEC therapy.