Effects of dietary vitamin C, vitamin E, and alpha-lipoic acid supplementation on the antioxidant defense system and immune-related gene expression in broilers exposed to oxidative stress by dexamethasone

Abstract

Vitamin C, vitamin E, and alpha-lipoic acid (ALA) are potent nutritional antioxidants, which are important for enhancing immunity. This study compared the effects of supplementation with vitamin C, vitamin E, or ALA on the antioxidant defense system and the expression of immune-related genes under oxidative stress induced by dexamethasone (DEX) in broilers. In total, 240 one-day-old female Recessive White Rock chickens were assigned randomly to either a basal diet (control group) or basal diet supplemented with vitamin C (200 mg/kg diet), vitamin E (100 mg/kg), or ALA (500 mg/kg) for 28 d starting from hatching. At 21 d of age, birds fed the ALA-supplemented diet had the highest plasma total antioxidant capacity (T-AOC) and superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-PX) enzyme activities, and the lowest plasma malondialdehyde (MDA) activity, as well as the lowest mRNA gene expression levels of interferon gamma (IFN-γ) and lipopolysaccharide-induced tumor necrosis factor-alpha factor (LITAF). At 23 d of age, the broilers in the 3 treatment groups were injected in the thigh muscle with DEX for 3 alternating days. In addition, the control group was divided into 2 equal groups, in which one was injected with saline and the other was injected with DEX. At 28 d of age, the DEX-ALA group (P < 0.05) had the highest activity levels for T-AOC, T-SOD, and GSH-PX in the plasma and liver (P < 0.05), and the greatest reduction in the MDA level. Dietary ALA significantly decreased the mRNA expression levels of the interleukin 1 β (IL-1β), IL-6, IFN-γ, and LITAF genes compared with the other groups during oxidative stress by DEX. In conclusion, this study suggests that in broilers, ALA is more effective for normalizing the oxidative stress induced by DEX than vitamin C or vitamin E.

Alpha lipoic acid inhibits oxidative stress‐induced apoptosis by modulating of Nrf2 signalling pathway after traumatic brain injury

“…More important is that ALA administered alleviated the mitochondrial apoptotic pathway following TBI and made the prognosis improve significantly . Therefore, it was reasonably believed that ALA can alleviate oxidative stress‐induced apoptosis following TBI . However, the mechanism of it on brain injury has not yet been undefined.…”

Oxidative Stress and Endoplasmic Reticulum Stress Are Involved in the Protective Effect of Alpha Lipoic Acid Against Heat Damage in Chicken Testes

“…In the past decade, there has been a growing number of investigations focusing on the effect of ALA supplementation on the antioxidant defense system in chickens. In female Recessive White Rock chickens (twenty-one-days-old), ALA (500 mg/kg diet) has been found to increase plasma SOD, GPx enzyme activities, and decrease plasma MDA activity [20]. Moreover, it has been demonstrated that dietary supplementation with 300 mg/kg ALA enhances the antioxidant capability and inhibits oxidative stress in liver and muscle in Ross male broiler chicks [48].…”

“…Since there was no technique available for separating the R form from the R/S mix, we did not consider the optical activity of ALA. The grower diet (22-42 days) ( Table 1) was formulated to meet National Research Council (NRC, 1994)-recommended requirements for all nutrients and according to the procedure described in our prior report [19], whereas the ALA diet was prepared by using a basal diet supplemented with ALA (500 mg/kg diet) based on a previous report [20]. The experimental treatment was performed based on our previous study but with minor modifications [19].…”

Evaluation of Ascorbic Acid or Curcumin Formulated in a Solid Dispersion on Salmonella Enteritidis Infection and Intestinal Integrity in Broiler Chickens

“…It has been reported that curcumin does not only down-regulate pro-inflammatory cytokines to reduce local inflammation in the intestine, but also reduces systemic inflammation triggered by the release of lipopolysaccharide (LPS) into circulation [44,51,52]. Similar to curcumin, AA is capable of decreasing the expression of proinflammatory cytokines such as IL-1, IL-6, IL-12, TNF-α and IFN-γ [53,54], which is indicative of better intestinal health.…”