Context: Atherosclerosis predisposes individuals to adverse cardiovascular events. Clinacanthus nutans L. (Acanthaceae) is a traditional remedy used for diabetes and inflammatory conditions.
Objectives: To investigate the anti-atherosclerotic activity of a C. nutans leaf methanol extract (CNME) in a type 2 diabetic (T2D) rat model induced by a high-fat diet (HFD) and low-dose streptozotocin.
Materials and methods: Sixty male Sprague-Dawley rats were divided into five groups: non-diabetic fed a standard diet (C), C + CNME (500 mg/kg, orally), diabetic fed an HFD (DM), DM + CNME (500 mg/kg), and DM + Metformin (DM + Met; 300 mg/kg). Treatment with oral CNME and metformin was administered for 4 weeks. Fasting blood glucose (FBG), serum lipid profile, atherogenic index (AI), aortic tissue superoxide dismutase levels (SOD), malondialdehyde (MDA), and tumour necrosis factor-alpha (TNF-α) were measured. The rats' aortas were stained for histological analysis and intima-media thickness (IMT), a marker of subclinical atherosclerosis.
Results: The CNME-treated diabetic rats had reduced serum total cholesterol (43.74%; p = 0.0031), triglycerides (80.91%; p = 0.0003), low-density lipoprotein cholesterol (56.64%; p = 0.0008), AI (51.32%; p < 0.0001), MDA (60.74%; p = 0.0026), TNF-α (61.78%; p = 0.0002), and IMT (39.35%; p < 0.0001) compared to untreated diabetic rats. SOD level, however, increased (53.36%; p = 0.0326). These CNME effects were comparable to those in the metformin-treated diabetic rats.
Conclusions: C. nutans possesses anti-atherosclerotic properties, which may be due to reductions in vascular tissue oxidative stress, inflammation, and serum AI. Continued studies on atherosclerotic animal models are suggested.
Keywords: MDA; SOD; TNF-α; anti-atherosclerosis; atherogenic index; intima-media thickness.