Effect of Ecdysterone on the Hepatic Transcriptome and Lipid Metabolism in Lean and Obese Zucker Rats.

Magdalena J M Marschall,Holger Zorn,Erika Most,Garima Maheshwari,Gaiping Wen,Sarah M Grundmann,Klaus Eder,Denise K Gessner,Robert Ringseis

doi:10.3390/ijms22105241

Abstract

Conflicting reports exist with regard to the effect of ecdysterone, the predominating representative of steroid hormones in insects and plants, on hepatic and plasma lipid concentrations in different rodent models of obesity, fatty liver, and diabetes, indicating that the effect is dependent on the rodent model used. Here, the hypothesis was tested for the first time that ecdysterone causes lipid-lowering effects in genetically obese Zucker rats. To test this hypothesis, two groups of male obese Zucker rats (n = 8) were fed a nutrient-adequate diet supplemented without or with 0.5 g ecdysterone per kg diet. To study further if ecdysterone is capable of alleviating the strong lipid-synthetic activity in the liver of obese Zucker rats, the study included also two groups of male lean Zucker rats (n = 8) which also received either the ecdysterone-supplemented or the non-supplemented diet. While hepatic and plasma concentrations of triglycerides and cholesterol were markedly higher in the obese compared to the lean rats (p < 0.05), hepatic and plasma triglyceride and cholesterol concentrations did not differ between rats of the same genotype fed the diets without or with ecdysterone. In conclusion, the present study clearly shows that ecdysterone supplementation does not exhibit lipid-lowering actions in the liver and plasma of lean and obese Zucker rats.

Highlights

IntroductionEcdysteroids are a class of steroid hormones occurring in insects, where they are referred to as zooecdysteroids, and in plants, where they are termed as phytoecdysteroids
The present study clearly shows that ecdysterone does not exhibit lipid-lowering actions in the liver and plasma of obese Zucker rats as demonstrated by unaltered triglyceride and cholesterol concentrations between obese rats fed with or without ecdysterone
No lipid-modulating effects of ecdysterone were found in lean Zucker rats

Summary

Introduction

Ecdysteroids are a class of steroid hormones occurring in insects, where they are referred to as zooecdysteroids, and in plants, where they are termed as phytoecdysteroids. Owing to the role of ecdysteroids in insects’ development and their importance as moulting hormones, the haemolymph concentration of ecdysterone is largely dependent on the insects developmental stage, with ecdysteroid levels being low through the intermoult but showing a major peak during each moult in the cuticle induction phase [3,4]. Evidence has been gained that all species have the capacity to produce at least low levels of phytoecdysteroids [5], but their concentration varies according to species, ecotype, developmental stage, plant part, and presence/absence of stress conditions. Very high levels of ecdysterone have been documented for roots and stems, respectively, of medicinal plants, such as Cyanotis arachnoidea [6] and Diploclisia glaucescens [7], and food plants, such as spinach (Spinacia oleracea) and quinoa (Chenopodium quinoa), were reported to contain noticeable levels of phytoecdysteroids [8], whose levels are strongly inducible by mechanical or insect damage of the root [9,10]

Methods

Results

Conclusion