Anti-hypertensive and renoprotective effects of berberine in spontaneously hypertensive rats

OBJECTIVES: We aimed to investigate the effects of berberine on renin-angiotensin system (RAS) and pro-inflammatory cytokines, as well as its effects on blood pressure and renal damage in spontaneously hypertensive rats. METHODS: Berberine was administrated to spontaneously hypertensive rats (SHR rats) between 3 and 20 weeks of age. Blood pressure was monitored in 3-, 6-, 9-, 12-, 16- and 20-week-old SHR rats and age-matched Wistar Kyoto rats (WKY rats). Besides, we measured levels of angiotensin II, aldosterone and pre-inflammatory cytokines (IL-6, IL-17, IL-23) in serum and kidney, as well as levels of collagen III and collagen IV in kidney and urinary markers of renal injury (osteopontin, kidney-injury-molecule (KIM-1) and albumin) in 3-, 6-, 9-, 12-, 16- and 20-week-old SHR rats and WKY rats. Glomerulosclerosis was also assessed with hematoxylin and eosin staining. RESULTS: SHR rats developed hypertension at the age of 6 weeks and had increased levels of angiotensin II, aldosterone, IL-6, IL-17, IL-23, collagen III, collagen IV, osteopontin, KIM-1 and albumin, as well as more severe glomerulosclerosis, compared to the aged-matched WKY rats. Berberine delayed the onset and attenuated the severity of hypertension, as well as partially inhibited the increases of the above substances in SHR rats. CONCLUSION: Berberine could delay the onset and attenuate the severity of hypertension, as well as ameliorate hypertension-induced renal damage in SHR rats. Furthermore, berberine could inhibit the activities of RAS and pre-inflammatory cytokines IL-6, IL-17 and IL-23, which are involved in the pathophysiology of hypertension.