Insect Meal as Alternative Protein Source Exerts Pronounced Lipid-Lowering Effects in Hyperlipidemic Obese Zucker Rats. Issue 4 (6th February 2019)

• Record Type: Journal Article
• Authors: Gessner, Denise K; Schwarz, Anne; Meyer, Sandra; Wen, Gaiping; Most, Erika; Zorn, Holger; Ringseis, Robert; Eder, Klaus
• Is Part Of: Journal of nutrition. Volume 149:Issue 4(2019)
• Page Start: 566
• Page End: 577
• Publication Date: 2019-02-06
• Subjects: insect protein -- obese rat -- hypolipidemic effect -- antisteatotic effect -- liver; Nutrition -- Periodicals; Diet -- Periodicals; 613.205
• DOI: 10.1093/jn/nxy256
• Languages: English
• ISSNs: 0022-3166

Abstract

ABSTRACT: Background: Specific dietary proteins exert strong health-related effects compared with casein. Objective: Herein, the hypothesis was tested using screening and conventional biochemical and molecular biological techniques that protein-rich insect meal compared with casein influences metabolic health in hyperlipidemic rats. Methods: A 4-wk feeding trial with male, 8-wk-old homozygous obese Zucker rats ( n = 36) and male, 8-wk-old heterozygous lean Zucker rats ( n = 12) was performed. Obese rats were randomly divided into 3 obese groups (OC, OI50, and OI100) of 12 rats each and lean rats served as a lean control group (LC). LC and OC were fed a control diet with 20% casein as protein source, whereas in OI50 and OI100 50% and 100% of the casein, respectively, was replaced isonitrogenously by insect meal from Tenebrio molitor L. All data were analyzed by 1-factor ANOVA, except transcriptomic data which were analyzed by groupwise comparisons with the OC group. Results: Transcript profiling revealed a coordinated inhibition by −17% to −521% and −37% to −859% of genes involved in fatty acid, triacylglycerol (TG), and cholesterol biosynthesis in the livers of OI100 and OI50, respectively, compared with OC ( P < 0.05). Enzyme activities of fatty acid synthase, glucose-6 phosphate dehydrogenase, and 3-hydroxy-3-methylglutaryl-coenzyme-A reductase in the liver were 100–150% greater in OC compared with LC, but reduced by 50–60% in OI100 compared with OC ( P < 0.05), to the same level as in LC. Liver and plasma concentrations of TG and cholesterol were 250–1000%, 30–800%, and 40–600% higher in OC, OI50, and OI100, respectively, than in LC ( P < 0.05), but 40–60% and 20–60% lower in OI100 and OI50, respectively, than in group OC ( P < 0.05). Plasma and liver concentrations of homocysteine were 20–30% lower in group OI100 than in group OC ( P < 0.05). Conclusion: Insect meal exerts pronounced lipid-lowering effects in hyperlipidemic rats and, thus, might be useful for hyperlipidemic individuals.