Dietary Soluble Celluloses Prevent Obesity-Related Metabolic Diseases in Fat Fed Hamsters

Authors: Yokoyama, Wallace - Wally

Submitted to: UJNR Food & Agricultural Panel Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 9/1/2006
Publication Date: 10/21/2006
Citation: Yokoyama, W.H. 2006. Dietary Soluble Celluloses Prevent Obesity-Related Metabolic Diseases in Fat Fed Hamsters. UJNR Food & Agricultural Panel Proceedings. FF:15-19.

Interpretive Summary: No Interpretive Summary Required.

Technical Abstract: Soluble, and to some extent, natural, unmodified cellulose demonstrate physiological activities, including plasma cholesterol-lowering. Male Syrian hamsters, ten per dietary treatment, were fed diets containing 5% total dietary fiber, 8% butterfat, 10% corn oil, 2% menhaden oil, and 0.1% cholesterol for three weeks to induce hypercholesterolemia. The dietary fiber included either 100 um Teflon beads, microcrystalline cellulose or water-soluble cellulose food gums. Hamsters fed Teflon had the highest levels of very low density lipoprotein (VLDL), low density lipoprotein (LDL) and total cholesterol: 73.8, 210.6 and 388.5 mg/dL, respectively. Compared to Teflon, MCC had similar levels of VLDL and slightly lower levels (173.9 mg/dL, P=0.01) of LDL cholesterol. Water-soluble cellulose gums, Methocel (trademark of Dow Chemical Co.), in a wide range of viscosities and dosage, significantly reduced plasma levels of LDL cholesterol (89.7-128.6 mg/dL) and VLDL cholesterol (20.9-29.7 mg/dL). In another experiment Syrian hamsters fed a high fat (HF) diet similar in fat content to the American diet became insulin resistant (IR). Replacing cellulose in a HF diet with hydroxypropylmethylcellulose (HPMC) significantly decreases the incidence of IR. HPMC significantly reduced the glucose infusion rate, fasting plasma insulin, plasma lipids, overall fat distribution in non-adipose tissues, and the cell size of adipose tissues. The underlying mechanisms of these beneficial physiological effects are unknown. A cDNA microarray, constructed from Chinese hamster ovary cells, was used to analyze gene expression in liver tissues from hamsters fed the HF or the HF with HPMC diets. Genes related to fat metabolism, glucose metabolism, insulin metabolism, inflammation, and glucose transport, were differentially expressed between the two groups. These results were confirmed by quantitative PCR.