The flavonoid morin restores blood pressure and lipid metabolism in DOCA-salt hypertensive rats

Abstract

Objective: This study was undertaken to investigate the antihypertensive and antihyperlipedimic potential of morin against deoxycorticosterone acetate (DOCA)-salt hypertensive rats.

Methods: Hypertension was induced in uninephrectomized rats (UNX) by weekly twice subcutaneous injection of DOCA (25 mg/kg) and 1% NaCl in the drinking water for six consecutive weeks. Morin (50 mg/kg) was administered to DOCA-salt rats orally using an intragastric tube daily for a period of 6 weeks.

Results: The DOCA-salt hypertensive rats showed significant elevation in mean arterial pressure (MAP), heart rate (HR) and reduction in body weight. A significant increase in the concentrations of plasma and tissue (liver, kidney, heart, and aorta) lipids such as total cholesterol, triglycerides, free fatty acids, phospholipids, plasma low-density and very low-density lipoproteins cholesterol, and a decrease in the concentration of high-density lipoprotein cholesterol were noticed in DOCA-salt hypertensive rats. Also, the levels of urinary protein and the activity of 3-hydroxy 3-methylglutaryl coenzyme A reductase in the plasma and tissues were increased, and lecithin cholesterol acyl transferase activity in the plasma was decreased in DOCA-salt rats. Morin supplementation (50 mg/kg) throughout the experimental period restored all the above parameters significantly.

Conclusion: Morin has a potential role in attenuating severe hypertension and hyperlipedimia.

Figure 1.

Effect of morin on MAP (A), heart rate (B), and body weight (C) in UNX and DOCA-salt hypertensive rats. Values are expressed as means ± standard deviation (SD) for six rats in each group. Values not sharing a common superscript differ significantly at P < 0.05 (DMRT).

Figure 2.

Effect of morin on LDL-C, VLDL-C, and HDL-C in plasma of UNX and DOCA-salt hypertensive rats. Values are expressed as means ± SD for six rats in each group. Values not sharing a common superscript differ significantly at P < 0.05 (DMRT).

Figure 3.

Effect of morin on the activity of HMG-CoA reductase in plasma and tissues of UNX and DOCA-salt hypertensive rats. Values are expressed as means ± SD for six rats in each group. Values not sharing a common superscript differ significantly at P < 0.05 (DMRT). *Lower ratio indicates higher enzyme activity.

Figure 4.

Effect of morin on the activity of LCAT in plasma of UNX and DOCA-salt hypertensive rats. Values are expressed as means ± SD for six rats in each group. Values not sharing a common superscript differ significantly at P < 0.05 (DMRT).

Figure 5.

Effect of morin on the levels of urinary protein in UNX and DOCA-salt hypertensive rats. Values are expressed as means ± SD for six rats in each group. Values not sharing a common superscript differ significantly at P < 0.05 (DMRT).

Figure 6.

Photomicrograph of liver section staining with H & E (A–F; 10×) and MT (G–L; 10×). UNX-control (A and G), UNX-control treated with morin alone (50 mg/kg) (B and H), DOCA-salt hypertensive rats (C–E and I–K) and DOCA-salt rats treated with morin (50 mg/kg) (F and L). Scale bar: 5 µm.