ABSTRACT
ObjectiveTo investigate the effect and mechanism of Dendrobium mixture （DMix）-containing serum on high glucose-induced podocyte injury in mice. MethodThe MPC5 mouse glomerular podocytes were cultured in vitro， and the optimal glucose concentration for modeling， modeling time， and concentration of DMix-containing serum for administration were determined. The cells were classified into normal （5.5 mmol·L-1 glucose+10% blank serum）， model （30 mmol·L-1 glucose+10% blank serum）， DMix-containing serum （30 mmol·L-1 glucose+10% DMix-containing serum）， ferroptosis inhibitor （Fer-1， 30 mmol·L-1 glucose+10% blank serum+1 μmol·L-1 Fer-1） groups. The corresponding kits were used to measure the levels of Fe2+ and lactate dehydrogenase （LDH） in cells. Enzyme-linked immunosorbent assay was employed to determine the content of glutathione （GSH） and lipid peroxide （LPO） in cells. Fluorescence probe was used to measure the reactive oxygen species （ROS） level. Real-time fluorescence quantitative polymerase chain reaction and Western blotting were employed to determine the mRNA and protein levels， respectively， of Wilms' tumor-1 （WT-1）， desmin， long chain acyl-CoA synthase 4 （ACSL4）， and glutathione peroxidase 4 （GPX4） in podocytes. ResultCompared with the blank group， the intervention with 30 mmol·L-1 glucose for 48 h reduced podocyte viability （P<0.01）， and the 10% DMix-containing serum showed the most significant improvement in podocyte viability （P<0.01）. Compared with the normal group， the model group presented elevated levels of Fe2+， LDH， LPO， and ROS， lowered GSH level， up-regulated mRNA and protein levels of desmin and ACSL4， and down-regulated mRNA and protein levels of WT-1 and GPX4 （P<0.01）. Compared with the model group， the DMix-containing serum lowered the Fe2+， LDH， LPO， and ROS levels， elevated the GSH level， down-regulated the mRNA and protein levels of desmin and ACSL4， and up-regulated the mRNA and protein levels of WT-1 and GPX4 in podocytes （P<0.05， P<0.01）. ConclusionDMix-containing serum exerts a protective effect on high glucose-induced podocyte injury by inhibiting ferroptosis.
ABSTRACT
OBJECTIVES: This study aimed to explore the efficacy of combination treatment with dendrobium mixture and metformin (Met) in diabetic cardiomyopathy (DCM) and its effects on NEAT1 and the Nrf2 signaling pathway. METHODS: H9c2 cells were maintained in medium supplemented with either low (5.5 mmol/L) or high (50 mmol/L) glucose. Male Sprague-Dawley rats were fed a high-glucose diet and administered a single, low dose of streptozotocin (35 mg/kg) via intraperitoneal injection to induce the development of DM. After induction of DM, the rats were treated with dendrobium mixture (10 g/kg) and Met (0.18 g/kg) daily for 4 weeks. Next, quantitative reverse transcription (qRT)-PCR and western blotting were performed to evaluate the expression levels of target genes and proteins. Flow cytometry was performed to assess apoptosis, and hematoxylin and eosin staining was performed to evaluate the morphological changes in rat cardiac tissue. RESULTS: In patients with diabetes mellitus (DM) and myocardial cells and heart tissues from rats with high glucose-induced DM, NEAT1 was downregulated, and the expression levels of Nrf2 were decreased (p<0.01, p<0.001). The combination of dendrobium mixture and Met upregulated the expression of NEAT1 which upregulated Nrf2 by targeting miR-23a-3p, resulting in reduced apoptosis and improved cardiac tissue morphology (p<0.01, p<0.001). CONCLUSION: Dendrobium mixture and Met upregulated the expression of NEAT1 in DCM, thereby inhibiting apoptosis of myocardial cells.