Effects of Thermally-Oxidized Frying Oils (Corn Oil and Lard) on Gut Microbiota in Hamsters

Abstract

Repeated reuse of frying oil raises health concerns due to the accumulation of oxidative products after each frying cycle. Gut microbiota is integral in lipid metabolism and immune regulation. The present study was designed to investigate the effects of thermally-oxidized corn oil and lard on gut microbiota in relation to atherosclerosis, inflammatory cytokines, and plasma lipids. Male Golden Syrian hamsters were randomly divided into four groups and fed one of four diets containing fresh corn oil (CF), oxidized corn oil (CO), fresh lard (LF), and oxidized lard (LO), for six weeks. CO and LO were prepared by deep-frying potatoes in corn oil or lard for seven days. Results indicated that oxidized oil and lard caused the loss of species diversity and richness of gut microbiota. Feeding CO and LO also reduced the body and adipose tissue weights, associated with genus Acetatifactor and Allobaculum. Plasma triacylglycerols significantly increased by 51% in the CO and 35% in the LO group compared with that in their CF and LF counterparts, respectively. CO could also affect the abundance of specific bacteria genera: Bacteroides, Barnesiella, Acetatifactor, Allobaculum, Clostridium_IV, Clostridium_XIVa, Coprococcus, Lactococcus, Paraprevotella, Parasutterella, and Oscillibacter. In addition, CO and LO could adversely remodel gut composition and affect intestinal production of short-chain fatty acids, pro-inflammatory biomarkers (LPS and IL-6), anti-inflammatory biomarker IL-10, and atherosclerotic progression. It was concluded that frying oil could adversely modulate the gut microbiota and exacerbate the atherosclerosis at least in a hypercholesterolemia hamster model.

Fried Soybean Oil Causes Systemic Low-Grade Inflammation by Disrupting the Balance of Gut Microbiota in Mice

“…The Shannon index analysis showed that the richness and diversity of gut microbiota in the MD and HD groups were significantly reduced at 6d, which is consistent with the results of a previous study in mice fed fried corn oil and lard for six weeks [14].…”

Long-term intake of thermo-induced oxidized oil results in anxiety-like and depression-like behaviors: involvement of microglia and astrocytes

“…47 In recent years, it has been reported that that frying oil adversely regulated the gut microbiota and exacerbated atherosclerosis in hypercholesterolemic hamster models. 48 Additionally, our laboratory has conducted studies showing that polar compounds generated during the high-temperature oxidation of oil can result in liver damage and disruption of the intestinal barrier. 16,18 These findings indicate that thermo-induced oxidized oil is a serious health hazard.…”

Hematobiochemical, antioxidant, and lipid alterations in mice feed with thermally oxidized coconut oil

“…Increase in blood urea nitrogen, serum CR, URE, UA, and glucose levels with reduced levels of total protein, albumin, and globulin along with changes in serum electrolyte concentrations, such Na, K, Mg, and Ca, show tissue toxicity and damage to visceral organs. Similarly (Kwek et al, 2022) reported that regular intake of deep-fried corn oil and lard could affect gut health (Aziz et al, 2024, Aziz et al, 2023a. A previous research conducted by (Baig et al, 2022) also demonstrated similar results.…”