The Alleviative Effect of Naringin Against Cardiovascular Dysfunction and Remodeling in Hypertensive Rats by Suppressing the Angiotensin II Pathway

FIGURE 1. Structure of naringin (Chen et al. 2016).

FIGURE 2. Effects of naringin or telmisartan on systolic blood pressure in the HG rats. Data are expressed as mean ± SD (n = 8). *p < 0.05 vs. CG, # p < 0.05 vs. HG, † p < 0.05 vs. HG + NR20. A p < 0.05 vs. week 0, B p < 0.05 vs. week 1, C p < 0.05 vs. week 2, D p < 0.05 vs. week 4. Data were analyzed using a two‐way ANOVA, followed by Tukey's post hoc test. CG, control group; HG, hypertensive group; NR20, naringin (20 mg/kg BW/day); NR40, naringin (40 mg/kg BW/day); TEL, telmisartan (5 mg/kg BW/day).

FIGURE 3. Effects of naringin or telmisartan on (A) % LVEF and (B) % LVFS in the HG. Data are expressed as mean ± SD (n = 6–7). *p < 0.05 vs. CG, # p < 0.05 vs. HG. Differences among groups were analyzed using one‐way analysis of variance, followed by Tukey's post hoc test. CG, control group; HG, hypertensive group; LVEF, left ventricular ejection fraction; LVFS, left ventricular fractional shortening; NR20, naringin (20 mg/kg BW/day); NR40, naringin (40 mg/kg BW/day); TEL, telmisartan (5 mg/kg BW/day).

FIGURE 4. Effects of naringin or telmisartan on the vascular response to (A) acetylcholine and (B) sodium nitroprusside in aortic rings. Data are expressed as mean ± SD (n = 8). *p < 0.05 vs. CG, # p < 0.05 vs. HG, † p < 0.05 vs. HG + NR20. Differences among groups were analyzed using one‐way analysis of variance, followed by the Tukey's post hoc test. CG, control group; HG, hypertensive group; NR20, naringin (20 mg/kg BW/day); NR40, naringin (40 mg/kg BW/day); TEL, telmisartan (5 mg/kg BW/day).

FIGURE 5. (A) Representative image of myocardial fibrosis under light and polarized light microscopes, scale bar: 50 μm. (B) Effects of naringin or telmisartan on the left ventricular fibrotic area in hypertensive rats. Data are expressed as mean ± SD (n = 8). *p < 0.05 vs. CG, # p < 0.05 vs. HG, † p < 0.05 vs. HG + NR20. Differences among groups were analyzed using one‐way analysis of variance, followed by the Tukey's post hoc test. CG, control group; HG, hypertensive group; NR20, naringin (20 mg/kg BW/day); NR40, naringin (40 mg/kg BW/day); TEL, telmisartan (5 mg/kg BW/day).

FIGURE 6. (A) Representative image of aortic fibrosis under light and polarized light microscopes in all experimental groups, scale bar: 100 μm. Effect of naringin or telmisartan on (B) aortic‐fibrotic area, (C) wall thickness, (D) cross‐sectional area, (E) luminal area, and (F) wall/lm ratio in all groups. Data are expressed as mean ± SD (n = 8). *p < 0.05 vs. CG, # p < 0.05 vs. HG. Differences among groups were analyzed using one‐way analysis of variance, followed by the Tukey's post hoc test. CG, control group; HG, hypertensive group; NR20, naringin (20 mg/kg BW/day); NR40, naringin (40 mg/kg BW/day); TEL, telmisartan (5 mg/kg BW/day).

FIGURE 7. Effects of naringin or telmisartan on (A) serum ACE activity and (B) plasma Ang II levels in hypertensive rats. Data are expressed as mean ± SD (n = 6–8). *p < 0.05 vs. CG, # p < 0.05 vs. HG, † p < 0.05 vs. HG + NR20. The differences among groups were analyzed using one‐way analysis of variance, followed by the Tukey's post hoc test. ACE, angiotensin‐converting enzyme; Ang II, angiotensin II; CG, control group; HG, hypertensive group; NR20, naringin (20 mg/kg BW/day); NR40, naringin (40 mg/kg BW/day); TEL, telmisartan (5 mg/kg BW/day).

FIGURE 8. Effects of naringin or telmisartan on the expression of (A) angiotensin II type 1 receptor (AT1R), (B) protein kinase C‐alpha (PKC‐α), (C) gp91phox (or NOX2), (D) Raf‐1, and (E) extracellular signal‐related kinases 1/2 (ERK1/2) proteins in the heart tissue. Data are expressed as mean ± SD (n = 4). *p < 0.05 vs. CG, # p < 0.05 vs. HG, † p < 0.05 vs. HG + NR20. Differences among groups were analyzed using a one‐way analysis of variance, followed by Tukey's post hoc test. CG, control group; HG, hypertensive group; NR20, naringin (20 mg/kg BW/day); NR40, naringin (40 mg/kg BW/day); TEL, telmisartan (5 mg/kg BW/day).