Assessment of Cholesterol, Glycemia Control and Short- and Long-Term Antihypertensive Effects of Smooth Hound Viscera Peptides in High-Salt and Fructose Diet-Fed Wistar Rats

Abstract

In this study, the antihypertensive activity of Purafect^®-smooth hound viscera protein hydrolysate (VPH) and its peptide fraction with molecular weight (MW) below 1 kDa (VPH-I) was investigated. In addition, the lipase inhibitory activity, as well the anticoagulant potential, in vitro, were assessed. The antihypertensive effects of VPH and VPH-I were studied during 24 h (short-term effect) and 30 days (long-term effect) using high-salt (18% NaCl) and -fructose (10%) diet (HSFD)-induced hypertension. Data showed that, 4 h post-administration of VPH and VPH-I (200 mg/kg BW), the systolic blood pressure of rats was reduced by about 6 and 9 mmHg, respectively. These effects were similar to that obtained with Captopril (~9 mmHg at t = 4 h). On the other hand, exposing the rats to daily to HSFD, coupled to the administration of viscera peptides, was found to attenuate hypertension. In addition, the proteins' treatments were able to correct lipid and glycemic disorders, by reducing the total cholesterol and triglyceride contents and resorting to the plasma glucose level, compared to the HSFD group. Overall, the present findings demonstrated the preventive effect of VPH-peptides from hypertension complications, as a result of their biological properties.

Keywords: anticoagulant activity; high salt and fructose diet; hypertension; lipase inhibitory activity; smooth hound peptide.

Figure 1

Pancreatic lipase inhibitory activity in vitro of UVP, VPH and VPH-I at different concentrations. Different letters in the same concentration within different samples indicate significant differences at p ≤ 0.05.

Figure 2

Effect of UVP, VPH and VPH-I on blood clotting time through (a) the activated partial thromboplastin time (aPTT), (b) the prothrombin ratio (PR) and (c) the thrombin time (TT). Different letters in the same concentration within different samples indicate significant differences at p ≤ 0.05.

Figure 3

(a) Body weight gain, (b) food and (c) water intake of the different groups of rats through and after the experimental period. Symbols (*, # and ¥) indicate significant differences compared to the normal diet (ND), HFSD and HFSD-Capto groups, respectively (p ≤ 0.05).

Figure 4

Changes in systolic blood pressure (SBP) of the different treatments following their (a) short- and (b) long-term administration. Different letters in Figure 4a indicate significant differences between groups at p ≤ 0.05 (n = 4). Symbols (*, # and ¥) in Figure 4b indicate significant differences compared to the ND, HFSD and HFSD-Capt groups, respectively, at p ≤ 0.05(n = 4).

Figure 4

Changes in systolic blood pressure (SBP) of the different treatments following their (a) short- and (b) long-term administration. Different letters in Figure 4a indicate significant differences between groups at p ≤ 0.05 (n = 4). Symbols (*, # and ¥) in Figure 4b indicate significant differences compared to the ND, HFSD and HFSD-Capt groups, respectively, at p ≤ 0.05(n = 4).

Figure 5

Plasma lipase activity of the different groups of rats at the end of the experimental period. Symbols (* and ¥) indicate significant differences compared to the ND, HFSD and HFSD-Capt groups, respectively (p ≤ 0.05).

Figure 6

Plasma glucose level of the different groups of rats at the end of the experimental period. Symbols (*, # and ¥) indicate significant differences compared to the ND, HFSD and HFSD-Capt groups, respectively (p ≤ 0.05).