Abstract Summary/Description
Increased intestinal permeability (IP) is associated with high blood pressure (BP). Blackberries (BL), blueberries (BB), raspberries (RB), and strawberries (SB) are widely studied for their anti-inflammatory and antioxidant effects and shown to preserve intestinal barrier function. Thus, the objective of this study was to evaluate the effects of a berry-rich diet on BP and IP in angiotensin (Ang) II-treated rats. Eight-week-old male Sprague-Dawley rats were fed an AIN-93M diet (control, Ang II, and Losartan (LOS; 20 mg/kg/BW)) or AIN-93M diet supplemented with 10% w/w freeze-dried berries (equal parts BL, BB, RB, and SB; Berry) for 8 weeks. Rats were implanted with subcutaneous osmotic minipumps delivering 0.9% saline (CON) or Ang II (270 ng/kg/BW/min; Ang II, LOS, and Berry) at week 4. BP was measured weekly. IP was measured by FITC-dextran 4K assay. Protein expression of inflammation, and oxidative stress in the proximal colon were assessed using Western Blot. Berry supplementation attenuated increases in BP after 8 weeks. IP was reduced in Berry group compared to Ang II, albeit not significantly. Protein expression of MYD88, an adaptor protein whose dysregulation may cause chronic inflammation, increased significantly in all groups. While the antioxidant enzyme, catalase, decreased in all groups, Berry preserved GPx1 expression. We demonstrate that a berry-rich diet protects against increases in BP and IP in Ang II-treated rats which may be through preservation of antioxidant enzymes. Future analyses will investigate tight junction gene expression and colon fibrosis.
