Effects of dietary fiber on the antioxidant capacity, immune status, and antioxidant-relative signaling molecular gene expression in rat organs

Abstract

This study was conducted to evaluate the effects of different fibers, such as dietary pea, sweet potato, and wheat bran fibers, on the antioxidant capacity, immune status, and antioxidant-related signaling molecules of rat organs. In a 30 day experiment, a total of 44 rats were randomly divided into four dietary groups. These rats were fed either with a control diet or three basal diets supplemented with 15% pea fiber, 15% sweet potato fiber, and 15% wheat bran fiber. Results are as follows: (1) different fibers, such as dietary pea, sweet potato, and wheat bran fibers, can effectively promote antioxidant defense by decreasing free radicals and increasing non-enzymatic and enzymatic antioxidant capacities in relevant organs (P < 0.05).(2) Pea, sweet potato, and wheat bran fiber significantly increase the mRNA levels of enzymatic antioxidant substances in relevant organs. Moreover, supplementation of these fibers remarkably increased the NF-E2-related nuclear factor 2, Kelch-like ECH-associated protein 1, and mammalian target of rapamycin in the spleen (P < 0.05). (3) These fibers also significantly upregulated the antiinflammatory mRNA level but downregulated the pro-inflammatory cytokine mRNA level in the jejunum, liver, and spleen. The mRNA level of transforming growth factor beta 1 also increased in rats with wheat bran fiber in different tissues (P < 0.05). In summary, pea fiber, sweet potato fiber, and wheat bran fiber supplements can improve the antioxidant capacity of plasma and relevant organs and regulate antioxidant-related signaling molecular expression in the jejunum, liver, and spleen of rats. Various fibers exerted different effects on immunity function in the jejunum, liver, and spleen by mediating the gene expression levels of anti-inflammatory and pro-inflammatory cytokines, TGF-b, and caspase 3.

Roles of dietary supplementation with arginine or N-carbamylglutamate in modulating the inflammation, antioxidant property, and mRNA expression of antioxidant-relative signaling molecules in the spleen of rats under oxidative stress

“…The quality of the total RNA was evaluated through agarose gel electrophoresis (1%). The total RNA purity of the spleen samples was assessed through spectrophotometric analysis at 260 and 280 nm according to a previous method ( Fang et al., 2017 ). The absorption ratios (260/280 nm) were between 1.8 and 2.0.…”

“…Amplification was completed with a total volume of 8 μL, which included cDNA (0.8 μL), primer pairs (1.6 μL), SYBR Premix Ex Taq_II (4 μL) (Takara, Dalian, China), and ddH 2 O (1.6 μL). The PCR procedure was in accordance with a previous study ( Fang et al., 2017 ). The expression results were assayed by using the method described by Livak and Schmittgen (2001) .…”

Effects of saccharicterpenin on antioxidant status and urinary metabolic profile of rats

“…Catalase and T-SOD are the 2 primary enzymes of the enzymatic components that exhibit catalytic activity with oxygen radicals. Catalase is an important endogenous antioxidant enzyme that can eliminate organic OH − and decompose H 2 O 2 into O 2 and H 2 O ( Fang et al., 2017 ). Superoxide dismutase can collaboratively convert superoxide anions into H 2 O and O 2 ( Cao et al., 2015 ).…”

Wheat bran as a natural remedy for COVID-19

“…A previous study [42] has shown that wheat bran phenolic compounds, such as feruloylated oligosaccharides, guard human erythrocytes against oxidative damage induced by the free radicals. Another study [43] investigated the impact of supplemental wheat bran fibers on the antioxidant capacity and the antioxidantassociated signaling molecules of rat organs. They analyzed the free radical-scavenging competence against O 2 − and OH − radicals and activities of enzymatic and non-enzymatic (glutathione (GSH)) antioxidant capacities.…”