Cardiovascular, antihyperlipidemic and antioxidant effects of oleanolic and ursolic acids in experimental...

Area of Science:

• Pharmacology and Toxicology
• Cardiovascular Research
• Natural Product Chemistry

Background:

• Genetic hypertension models, like Dahl salt-sensitive (DSS) rats, are crucial for studying cardiovascular diseases.
• Insulin resistance is a common comorbidity in genetic hypertension, complicating treatment strategies.
• Triterpenoids, such as oleanolic acid (OA) and ursolic acid (UA), are natural compounds with potential therapeutic benefits.

Purpose of the Study:

• To investigate the cardiovascular, antihyperlipidemic, antioxidant, diuretic/saluretic, and hypoglycemic activities of oleanolic acid (OA) and ursolic acid (UA).
• To evaluate the efficacy of OA and UA in preventing the development of severe hypertension in a rat model.

Main Methods:

• Assessed the toxicity of OA and UA using LC50 measurements.
• Administered daily doses of OA and UA (60 mg/kg b.w., i.p.) to Dahl salt-sensitive (DSS) rats for 6 weeks.
• Monitored cardiovascular parameters (blood pressure, heart rate), lipid profiles, antioxidant enzyme activity (GPx, SOD), and blood glucose levels.

Main Results:

• OA and UA demonstrated low toxicity (LC50 0.10 and 0.95 mg/ml).
• Both compounds prevented severe hypertension development, attributed to diuretic, natriuretic, and saluretic effects.
• Observed significant reductions in heart rate, LDL, triglycerides, and blood glucose, alongside increased antioxidant enzyme activity (GPx, SOD).

Conclusions:

• Oleanolic acid and ursolic acid exhibit multifaceted pharmacological effects beneficial for managing hypertension.
• The antihypertensive effects are linked to diuretic, cardiac, lipid-lowering, antioxidant, and hypoglycemic actions.
• These findings represent novel in vivo antihypertensive effects of OA and UA, warranting further mechanistic investigation.