Royal jelly ameliorates insulin resistance in fructose-drinking rats

Biol Pharm Bull. 2008 Nov;31(11):2103-7. doi: 10.1248/bpb.31.2103.

Abstract

Royal jelly (RJ) is known to contain excellent nutrition and a variety of biological activities. The present study was designed to investigate the effects of RJ on insulin resistance (hyperinsulinemia) in fructose-drinking rats (FDR; insulin resistance animal model). Male Wistar rats (6 weeks old) received 15% fructose solution in drinking water for 8 weeks. FDR showed significant increases in plasma levels of insulin and triglyceride, Homeostasis Model Assessment ratio (HOMA-R, an index of insulin resistance), and systolic blood pressure, but not blood glucose levels, when compared with control rats. RJ (100, 300 mg/kg, p.o.) treatment for 8 weeks significantly decreased the plasma levels of insulin and triglyceride, HOMA-R, without affecting blood glucose or total cholesterol levels and tended to lower systolic blood pressure. In isolated and perfused mesenteric vascular beds of FDR, RJ treatment resulted in a significant reduction in sympathetic nerve-mediated vasoconstrictor response to periarterial nerve stimulation (PNS) and tended to increase the calcitonin gene-related peptide (CGRP) nerve-mediated vasodilator response to PNS, compared with those in untreated FDR. However, RJ treatment did not significantly affect norepinephrine-induced vasoconstriction or CGRP-induced vasodilation. These results suggest that RJ could be an effective functional food to prevent insulin resistance associated with the development of hypertension.

MeSH terms

  • Administration, Oral
  • Animals
  • Blood Glucose / analysis
  • Blood Pressure / drug effects
  • Body Weight / drug effects
  • Cholesterol / blood
  • Drinking
  • Electric Stimulation
  • Fatty Acids / pharmacology*
  • Fructose / administration & dosage
  • Fructose / adverse effects*
  • Hypertension / metabolism
  • Hypertension / physiopathology
  • Hypertension / prevention & control
  • Insulin / blood
  • Insulin Resistance*
  • Male
  • Mesenteric Arteries / drug effects
  • Mesenteric Arteries / innervation
  • Mesenteric Arteries / physiology
  • Perfusion
  • Peripheral Nervous System / physiology
  • Rats
  • Rats, Wistar
  • Triglycerides / blood
  • Vasoconstriction / drug effects
  • Vasoconstrictor Agents / pharmacology
  • Vasodilation / drug effects

Substances

  • Blood Glucose
  • Fatty Acids
  • Insulin
  • Triglycerides
  • Vasoconstrictor Agents
  • Fructose
  • Cholesterol
  • royal jelly