Pineapple fruit improves vascular endothelial dysfunction, hepatic steatosis, and cholesterol metabolism in rats fed a high-cholesterol diet

Food Funct. 2022 Oct 3;13(19):9988-9998. doi: 10.1039/d2fo01199a.

Abstract

Hypercholesterolaemia is a significant risk factor for developing vascular disease and fatty liver. Pineapple (Ananas comosus), a tropical fruit widely cultivated in Asia, is reported to exhibit antioxidant and cholesterol-lowering activity; however, the potential hypolipidaemic mechanisms of pineapple fruit remain unknown. Therefore, we aimed to identify the anti-hypercholesterolaemic mechanism of pineapple fruit and to study the effect of pineapple fruit intake on hypercholesterolaemia-induced vascular dysfunction and liver steatosis in a high-cholesterol diet (HCD)-fed rats. Male Sprague Dawley rats were fed with standard diet or HCD, and the pineapple fruit was orally administered to HCD-fed rats for 8 weeks. At the end of treatment, vascular reactivity and morphology of aortas, as well as serum nitrate/nitrite (NOx), were determined. Liver tissues were also examined for histology, lipid content, 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) activity, and protein expression of cholesterol metabolism-related enzymes. Results showed that pineapple fruit reduced the levels of hepatic cholesterol and triglycerides, and improved histological characteristics of a fatty liver in HCD-fed rats. Pineapple fruit also increased serum NOx, restored endothelium-dependent vasorelaxation, and reduced structural alterations in aortas of rats fed the HCD. In addition, a reduction of HMGCR activity and the downregulation of hepatic expression of HMGCR and sterol-regulatory element-binding protein 2 (SREBP2), as well as the upregulation of hepatic expression of cholesterol 7α-hydroxylase (CYP7A1) and LDL receptor (LDLR) were found in pineapple fruit-treated hypercholesterolaemic rats. These results indicate that pineapple fruit consumption can restore fatty liver and protect vascular endothelium in diet-induced hypercholesterolaemia through an improvement of hepatic cholesterol metabolism.

MeSH terms

  • Ananas* / metabolism
  • Animals
  • Antioxidants / pharmacology
  • Cholesterol / metabolism
  • Cholesterol 7-alpha-Hydroxylase / metabolism
  • Diet
  • Fatty Liver* / metabolism
  • Fruit / metabolism
  • Hypercholesterolemia* / drug therapy
  • Hypercholesterolemia* / metabolism
  • Hyperlipidemias* / metabolism
  • Lipid Metabolism
  • Liver / metabolism
  • Male
  • Nitrates
  • Nitrites / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, LDL / metabolism
  • Sterol Regulatory Element Binding Protein 2 / metabolism
  • Triglycerides / metabolism
  • Vascular Diseases* / metabolism

Substances

  • Antioxidants
  • Nitrates
  • Nitrites
  • Receptors, LDL
  • Sterol Regulatory Element Binding Protein 2
  • Triglycerides
  • Cholesterol
  • Cholesterol 7-alpha-Hydroxylase