Dietary supplementation with peanut skin polyphenolic extracts (PSPE) reduces hepatic lipid and glycogen stores in mice fed an atherogenic diet

Authors: Toomer, Ondulla; Vu, Thien; PEREIRA, MARION - Us Food & Drug Administration (FDA); WILLIAMS, KRISTINA - Us Food & Drug Administration (FDA)

Submitted to: Journal of Functional Foods
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/23/2019
Publication Date: 3/13/2019
Citation: Toomer, O.T., Vu, T.C., Pereira, M., Williams, K. 2019. Dietary supplementation with peanut skin polyphenolic extracts (PSPE) reduces hepatic lipid and glycogen stores in mice fed an atherogenic diet. Journal of Functional Foods. 55:362–370. https://doi.org/10.1016/j.jff.2019.02.041.
DOI: https://doi.org/10.1016/j.jff.2019.02.041

Interpretive Summary: Peanut skins, a considerable waste product generated in the peanut industry (˜40 to 70 million pounds annually) accounts for approximately 2.0 to 3.5% of the total processed shelled edible-grade peanuts produced annually in the U.S., which is predominately discarded and of no current economic value. Studies to date have shown very little uses for peanut skins as a feed ingredient for livestock. Thus, one of the objectives of the Market Quality and Handling (MQH) Unit is the extraction and isolation of compounds from peanut skins to develop value-added applications for a low value agricultural waste product. In this study, we aimed to determine the biological effects of feeding peanut skin phenolic extracts (PSPE) to mice fed a high fat, high-cholesterol diet (atherogenic) in comparison to mice fed an atherogenic or control diet for 16 weeks. Tissue and blood samples were collected for analysis. This study determined that mice fed the PSPE high fat, high-cholesterol diet had improved blood glucose levels, reduced hepatic glycogen and lipid stores, and enhanced immunity in comparison to the other treatment groups. This study collectively implies that phenolic compounds extracted from peanut skins may be a value added food ingredient and an affordable plant source of antioxidants of health benefit to consumer and serve as a functional food ingredient useful in the management of human-health related conditions pertaining to energy metabolism.

Technical Abstract: The phenolic compounds found in red wine, grapes and peanut skins have been identified as bioactive compounds responsible for reduced mortality rates associated with cardiovascular disease. Resveratrol supplementation reduced liver lipids and inflammation in a mouse model. We aimed to assess the effects of feeding a peanut skin phenolic extract supplemented atherogenic (PSPE), atherogenic or control diet in 30 adult mice. Bodyweights were collected weekly and plasma glucose levels were determined bi-weekly. At termination, lymphocyte populations, hepatic cholesterol and glycogen quantitated. Mice fed the PSPE-diet had significantly improved bodyweights, hepatic glycogen and blood plasma glucose levels in comparison to the other treatment groups. Moreover, hepatic cholesterol and lipid storage was reduced in mice fed the PSPE diet. Thus, this study demonstrates that phenolic extracts from peanut skins could serve as a functional food ingredient and have potential uses in the management of human-health related conditions pertaining to energy metabolism.