Sun Linlin, Xiao Yujiao, San Wenqing, Chen Yun, Meng Guoliang
Department of Pharmacy, Affiliated Maternity & Child Health Care Hospital of Nantong University, Nantong, China.
Department of Nantong Institute of Genetics and Reproductive Medicine, Affiliated Maternity & Child Health Care Hospital of Nantong University, Nantong, China.
Heliyon. 2024 Mar 29;10(7):e28921. doi: 10.1016/j.heliyon.2024.e28921. eCollection 2024 Apr 15.
Diabetic cardiomyopathy is one common cardiovascular complication without effective treatments. Dihydromyricetin (DHY), a natural dihydroflavonol compound extracted from , possesses versatile pharmacologically important effects. In our current research, we planned to evaluate the impact and probable DHY mechanisms in high glucose (HG)-induced cardiomyocytes.
Primary cardiomyocytes were pretreated with different concentrations of DHY (0, 20, 40, 80, 160, and 320 μM) for various time (0, 1, 2, 4, 12, and 24 h). They were then stimulated for 48 h with 5.5 mmol/L normal glucose (NG) and 33.3 mmol/L high glucose (HG). Cell viability, adenosine-triphosphate (ATP) levels, and lactate dehydrogenase (LDH) release of cardiomyocytes were detected. JC-1 staining was employed to measure the mitochondrial membrane potential. MitoSOX staining and dihydroethidium (DHE) staining were applied to evaluate the oxidative stress levels. TDT mediated dUTP nick end labeling (TUNEL) was used to measure apoptotic levels. Expressions of calcium/calmodulin-dependent protein kinase II (CaMKII), phospholamban (PLB), optic atrophy 1 (OPA1), dynamin-related protein 1 (DRP1), caspase 3, mixed kinase lineage domain like protein (MLKL), receptor interacting protein kinase 3 (RIPK3), and receptor interacting protein kinase 1 (RIPK1) were detected by immunofluorescence and/or Western blot.
DHY improved cell viability, enhanced ATP level, and decreased LDH content in HG-stimulated cardiomyocytes, suggesting DHY attenuating cell injury. DHY reduced number of TUNEL positive cells, inhibited RIPK3 and cleaved-caspase 3 expression, implying DHY alleviated necroptosis in HG-stimulated cardiomyocytes. DHY diminished JC-1 monomers, DHE and MitoSOX fluorescence intensity as well as DRP1 expression but increased JC-1 aggregates intensity and OPA1 expression, indicating that DHY attenuated oxidative stress in HG-stimulated cardiomyocytes. DHY also attenuated CaMKII activity by suppressed PLB phosphorylation and inhibited CaMKII oxidation in HG-stimulated cardiomyocytes.
HG-induced cardiomyocytes injury was alleviated wherein DHY attenuated necroptosis, repressed ROS production, and inhibited CaMKII oxidation, suggesting that DHY may serve as potential agent to prevent and treat diabetic cardiomyopathy.
糖尿病性心肌病是一种常见的心血管并发症，尚无有效治疗方法。二氢杨梅素（DHY）是从[具体来源未给出]中提取的一种天然二氢黄酮醇化合物，具有多种重要的药理作用。在我们当前的研究中，我们计划评估二氢杨梅素在高糖（HG）诱导的心肌细胞中的作用及可能机制。
原代心肌细胞用不同浓度的二氢杨梅素（0、20、40、80、160和320 μM）预处理不同时间（0、1、2、4、12和24小时）。然后用5.5 mmol/L正常葡萄糖（NG）和33.3 mmol/L高糖（HG）刺激48小时。检测心肌细胞的活力、三磷酸腺苷（ATP）水平和乳酸脱氢酶（LDH）释放。采用JC-1染色测量线粒体膜电位。应用MitoSOX染色和二氢乙锭（DHE）染色评估氧化应激水平。采用末端脱氧核苷酸转移酶介导的dUTP缺口末端标记（TUNEL）法测量凋亡水平。通过免疫荧光和/或蛋白质印迹法检测钙/钙调蛋白依赖性蛋白激酶II（CaMKII）、受磷蛋白（PLB）、视神经萎缩蛋白1（OPA1）、动力相关蛋白1（DRP1）、半胱天冬酶3、混合激酶结构域样蛋白（MLKL）、受体相互作用蛋白激酶3（RIPK3）和受体相互作用蛋白激酶1（RIPK1）的表达。
二氢杨梅素改善了高糖刺激的心肌细胞的活力，提高了ATP水平，降低了LDH含量，表明二氢杨梅素减轻了细胞损伤。二氢杨梅素减少了TUNEL阳性细胞数量，抑制了RIPK3和裂解的半胱天冬酶3的表达，这意味着二氢杨梅素减轻了高糖刺激的心肌细胞中的坏死性凋亡。二氢杨梅素减少了JC-1单体、DHE和MitoSOX荧光强度以及DRP1表达，但增加了JC-1聚集体强度和OPA1表达，表明二氢杨梅素减轻了高糖刺激的心肌细胞中的氧化应激。二氢杨梅素还通过抑制PLB磷酸化减轻了CaMKII活性，并抑制了高糖刺激的心肌细胞中的CaMKII氧化。
高糖诱导的心肌细胞损伤得到减轻，其中二氢杨梅素减轻了坏死性凋亡，抑制了活性氧生成，并抑制了CaMKII氧化，这表明二氢杨梅素可能作为预防和治疗糖尿病性心肌病的潜在药物。
