Background: Diabetic cardiomyopathy (DCM) is a severe and progressive cardiac complication of diabetes characterized by inflammation, apoptosis, and myocardial fibrosis. DCM significantly contributes to heart failure and mortality in diabetic patients. Currently, available treatments target symptomatic relief and glycemic control but fail to address the molecular underpinnings of DCM. This study investigates the cardioprotective effects of Nymphaea lotus, a medicinal plant used to manage diabetes and its complications, in diabetic rats.
Materials and Methods: Male Wistar rats were divided into control and high-fat diet (HFD)/streptozotocin (STZ)-induced diabetic groups. Diabetic rats were further subdivided and administered varying doses (50, 100, and 400 mg/kg) of N. lotus leaf extract or Metformin (the standard drug) at the end of the fourth week. Heart tissue samples were collected for the extraction and quantification of total RNA. Quantitative reverse transcriptase PCR (qRT-PCR) was conducted to assess the gene expression of apoptotic (BAX, BCL-2, caspase 3), inflammatory (IL-1β, TNF-α), and antioxidative (NRF2) genes.
Results: Treatment with N. lotus resulted in a significant decrease in the expression of pro-apoptotic genes (BAX, caspase 3) and pro-inflammatory genes (IL-1β, TNF-α), while upregulating the anti-apoptotic gene BCL-2 and the antioxidative regulator. BAX was markedly elevated in 50 mg, Metformin, and Untreated groups compared to HFD/STZ, but suppressed in HFD/STZ vs. 100 mg. CASPASE3 showed a dose-dependent pattern, decreasing at 50 mg but significantly enhanced by Metformin relative to both HFD/STZ and 50 mg. IL1α and TNFα were consistently suppressed in HFD/STZ but restored by Metformin and Untreated groups. BCL2 exhibited strong upregulation in the 50 mg group, indicating anti-apoptotic activity, while NRF2 was moderately reduced under HFD/STZ.
Conclusion: The present findings demonstrate that HFD/STZ induction significantly disrupted apoptotic, inflammatory, and oxidative stress genes, while treatments produced distinct restorative responses.
