METHODS: Diabetes was induced using streptozotocin (60 mg/kg, i.v.) followed by nicotinamide (210 mg/kg, intraperitoneal (i.p.)). MAD (50 mg/kg) was administered orally for 4 weeks, commencing 15 days after induction of diabetes; resveratrol (10 mg/kg) was used as a positive control. Fasting blood glucose, plasma insulin, HbA1c, liver and lipid parameters were measured, along with antioxidant enzymes and malondialdehyde as an index of lipid peroxidation; histological and immunohistochemical studies were also undertaken.
KEY FINDINGS: MAD normalized the elevated fasting blood glucose levels. This was associated with increased plasma insulin concentrations. MAD alleviated oxidative stress by improving enzymatic antioxidants and reducing lipid peroxidation. Histopathological examination showed significant recovery of islet structural degeneration and an increased area of islets. Immunohistochemical staining showed increased insulin content in islets of MAD-treated rats.
CONCLUSIONS: The results demonstrate an antidiabetic effect of MAD associated with preservation of β-cell structure and function.
RESULTS: Further investigation into CL bioactive fraction (II-F7) revealed significant dose-dependent growth inhibitory effects on MCF-7 cells, which were attributed to the induction of apoptosis, as evidenced by the presence of apoptotic bodies, fragmented DNA, and disruption of mitochondrial membrane potential. Additionally, treatment with CL bioactive fraction (II-F7) upregulated the expression of pro-apoptotic genes (DDIT3, GADD45G and HRK) and significantly increased the activities of caspase-8 and caspase-9.
CONCLUSION: Overall, this study suggests that bioactive fraction (II-F7) from CL extract has significant and selective cytotoxicity against MCF-7 cells through inducing apoptosis and has potential as a therapeutic agent for breast cancer treatment.