Objective : To explore the effect of Wilms′ tumor 1-associated protein(WTAP) on tissue collagen deposition in pulmonary fibrosis caused by bleomycin. Methods : 60 mice were randomly divided into four groups: control group(Control group), Bleomycin-induced pulmonary fibrosis group(BLM group), pulmonary fibrosis lentivirus empty vector control group(BLM+LV-NC group), pulmonary fibrosis WTAP lentivirus group virus group(BLM+LV-WTAP group). Experimental pulmonary fibrosis mouse model was established by subcutaneous injection of bleomycin(35 mg/kg) into the abdomen, twice a week for a total of 8 times. After modeling, Western Blot was used to detect the protein expression of fibrosis-related markers α-smooth muscle actin(α-SMA), type I collagen(Collagen Ⅰ), fibronectin(Fibronectin), and WTAP protein. Masson staining and Sirius Red staining were used to detect collagen deposition. RT-qPCR was used to detect WTAP mRNA expression, WTAP lentivirus infection effect, and Collagen Ⅰ mRNA expression. Results: Compared with the Control group, the expression of pulmonary fibrosis markers α-SMA(P<0.001), Collagen Ⅰ(P<0.001), and Fibronectin(P<0.01) protein in the BLM group all increased. Masson staining(P<0.001) and Sirius Red staining(P<0.001) confirmed that significant collagen deposition occurred in the lung tissue of the BLM group. In addition, the expression of WTAP protein in the lung tissue of the BLM group increased(P<0.01). Compared with the Control group, the expression of WTAP mRNA in the BLM group increased(P<0.001). Compared with the BLM+LV-NC group, the expression of WTAP mRNA in the tissues of the BLM+LV-WTAP group decreased(P<0.001), proving that virus infection is effective. After infection with WTAP lentivirus, collagen fiber deposition decreased(P<0.001), Collagen Ⅰ mRNA(P<0.001) level decreased, and protein(P<0.001) expression decreased in the BLM+LV-WTAP group. Conclusion Knocking down of WTAP can reduce collagen deposition in bleomycin-induced pulmonary fibrosis tissue in mice and improve experimental pulmonary fibrosis.

Objective: To investigate the effect of sirtuin 2(SIRT2) on the proliferation and migration of cardiac fibroblasts(CFs)in C57BL/6 mice under angiotensin II(Ang Ⅱ) stimulation. Methods : The hearts were taken from 1 to 2 days C57BL/6 milk mice. After cutting and digesting, CFs were extracted by different adhesion centrifugation. After CFs attachment, the cells were cultured under control medium and Ang Ⅱ(100 nmol/L) medium and treated using OE-SIRT2 plasmid to overexpression the SIRT2 gene. RT-qPCR was used to detect mRNA expression of SIRT2 proliferating cell nuclear antigen(PCNA), periostin(POSTN)and type Ⅰ collagen procollagen A1(Col1A1), Western blot assay was used to measure the protein expression levels of SIRT2, PCNA, POSTN and Col1A1, CCK-8 assay and EdU assay were used to evaluate CFs proliferation rate, Transwell experiment was used to assess CFs migration activity. Results: Compared with control group, Ang Ⅱ stimulation led to down-regulation of SIRT2 expression in CFs, increased collagen expression, and promoted CFs proliferation and migration. The expression of SIRT2 was up regulated in CFs treated with OE-SIRT2 plasmid under Ang Ⅱ stimulation, Col1A1, POSTN and PCNA expression was down regulated, and CFs proliferation and migration ability decreased. Conclusion Overexpression of SIRT2 can inhibit the proliferation and migration of CFs under Ang Ⅱ stimulation, indicating that SIRT2 may be a key regulatory point in the onset and progression of cardiac fibrosis.

Objective:To explore the predictive value of mitochondrial oxidative stress biomarkers 8-hydroxy-2′-deoxyguanosine (8-OHdG) and mitochondrial DNA (mtDNA) copy number in asymptomatic type 2 diabetes mellitus (T2DM) patient with left ventricular diastolic dysfunction.Methods:This was a cross-sectional study. T2DM patients without cardiovascular symptoms who were admitted to the Department of Endocrinology, the Third Affiliated Hospital of Soochow University between April 2018 and May 2022 were enrolled. According to the HFA-PEFF score, the enrolled patients were divided into three groups: the T2DM group (HFA-PEFF score ≤1), the left ventricular diastolic dysfunction suspected positive group (HFA-PEFF score 2-4), and the left ventricular diastolic dysfunction positive group (HFA-PEFF score ≥5). Multivariate logistic regression was performed to evaluate the association of plasma 8-OHdG level and mtDNA copy number with left ventricular diastolic dysfunction in patients with T2DM. Receiver operating characteristic curves were constructed to evaluate the predictive ability of plasma 8-OHdG level and its combination with baseline clinical data for left ventricular diastolic dysfunction in T2DM patients, and stratified analysis was performed by sex, age, diabetes duration and hemoglobin A1c levels.Results:A total of 163 T2DM patients without cardiovascular symptoms, aged (54.0±8.7) years, including 93 males (57.1%), were enrolled. Compared with T2DM group, patients in left ventricular diastolic dysfunction suspected positive and positive groups (44.59 (27.72, 55.58) μg/L vs. 93.23 (59.58, 129.80) μg/L vs. 101.91 (71.39, 137.39) μg/L, P<0.05) had significantly higher plasma 8-OHdG levels, while mtDNA copy number showed no statistically significant differences among the three groups (both P>0.05). Multivariate logistic regression analysis showed that after adjusting for confounder factors, elevated plasma 8-OHdG level were independently associated with both suspected positive left ventricular diastolic dysfunction ( OR=1.036, 95% CI 1.019-1.053, P<0.001) and positive left ventricular diastolic dysfunction ( OR=1.035, 95% CI 1.018-1.053, P<0.001). mtDNA copy number showed no significant association with T2DM accompanied by left ventricular diastolic dysfunction ( P>0.05). Stratified analysis indicated that elevated plasma 8-OHdG level was significantly associated with left ventricular diastolic dysfunction in different age, sex, diabetes course and hemoglobin A1c levels subgroups (all P<0.05). The receiver operating characteristic curves indicated that the combination of baseline clinical data with 8-OhdG level ( AUC=0.871, 95% CI 0.814-0.928, P<0.001) is more effective in predicting asymptomatic left ventricular diastolic dysfunction in T2DM patients than 8-OHdG ( AUC=0.783, 95% CI 0.704-0.861, P<0.001) or baseline clinical data ( AUC=0.736, 95% CI 0.647-0.826, P=0.001) alone. Conclusion:The mitochondrial oxidative stress biomarker 8-OHdG combined with baseline clinical data has good predictive value for asymptomatic left ventricular diastolic dysfunction in T2DM patients, and is expected to be a biomarker to identify diabetes mellitus with asymptomatic diastolic dysfunction.

Objective:To explore the predictive value of mitochondrial oxidative stress biomarkers 8-hydroxy-2′-deoxyguanosine (8-OHdG) and mitochondrial DNA (mtDNA) copy number in asymptomatic type 2 diabetes mellitus (T2DM) patient with left ventricular diastolic dysfunction.Methods:This was a cross-sectional study. T2DM patients without cardiovascular symptoms who were admitted to the Department of Endocrinology, the Third Affiliated Hospital of Soochow University between April 2018 and May 2022 were enrolled. According to the HFA-PEFF score, the enrolled patients were divided into three groups: the T2DM group (HFA-PEFF score ≤1), the left ventricular diastolic dysfunction suspected positive group (HFA-PEFF score 2-4), and the left ventricular diastolic dysfunction positive group (HFA-PEFF score ≥5). Multivariate logistic regression was performed to evaluate the association of plasma 8-OHdG level and mtDNA copy number with left ventricular diastolic dysfunction in patients with T2DM. Receiver operating characteristic curves were constructed to evaluate the predictive ability of plasma 8-OHdG level and its combination with baseline clinical data for left ventricular diastolic dysfunction in T2DM patients, and stratified analysis was performed by sex, age, diabetes duration and hemoglobin A1c levels.Results:A total of 163 T2DM patients without cardiovascular symptoms, aged (54.0±8.7) years, including 93 males (57.1%), were enrolled. Compared with T2DM group, patients in left ventricular diastolic dysfunction suspected positive and positive groups (44.59 (27.72, 55.58) μg/L vs. 93.23 (59.58, 129.80) μg/L vs. 101.91 (71.39, 137.39) μg/L, P<0.05) had significantly higher plasma 8-OHdG levels, while mtDNA copy number showed no statistically significant differences among the three groups (both P>0.05). Multivariate logistic regression analysis showed that after adjusting for confounder factors, elevated plasma 8-OHdG level were independently associated with both suspected positive left ventricular diastolic dysfunction ( OR=1.036, 95% CI 1.019-1.053, P<0.001) and positive left ventricular diastolic dysfunction ( OR=1.035, 95% CI 1.018-1.053, P<0.001). mtDNA copy number showed no significant association with T2DM accompanied by left ventricular diastolic dysfunction ( P>0.05). Stratified analysis indicated that elevated plasma 8-OHdG level was significantly associated with left ventricular diastolic dysfunction in different age, sex, diabetes course and hemoglobin A1c levels subgroups (all P<0.05). The receiver operating characteristic curves indicated that the combination of baseline clinical data with 8-OhdG level ( AUC=0.871, 95% CI 0.814-0.928, P<0.001) is more effective in predicting asymptomatic left ventricular diastolic dysfunction in T2DM patients than 8-OHdG ( AUC=0.783, 95% CI 0.704-0.861, P<0.001) or baseline clinical data ( AUC=0.736, 95% CI 0.647-0.826, P=0.001) alone. Conclusion:The mitochondrial oxidative stress biomarker 8-OHdG combined with baseline clinical data has good predictive value for asymptomatic left ventricular diastolic dysfunction in T2DM patients, and is expected to be a biomarker to identify diabetes mellitus with asymptomatic diastolic dysfunction.