Inflammation is an underlying problem for many disease states and has been implicated in iron deficiency (ID). This study aimed to determine whether iron status is improved by epigallocatechin-3-gallate (EGCG) through reducing inflammation. Thirty-two male Sprague–Dawley rats were fed an iron-deficient diet for 2 weeks and then randomly divided into four groups (n 8 each): positive controls, negative controls, lipopolysaccharide (LPS, 0⋅5 mg/kg body weight), and LPS + EGCG (LPS plus 600 mg EGCG/kg diet) for 3 additional weeks. The study involved testing two control groups, both treated with saline. One group (positive control) was fed a regular diet containing standard iron, while the negative control was fed an iron-deficient diet. Additionally, two treatment groups were tested. The first group was given LPS, while the second group was administered LPS and fed an EGCG diet. Iron status, hepcidin, C-reactive protein (CRP), serum amyloid A (SAA), and interleukin-6 (IL-6) were measured. There were no differences in treatment groups compared with control in CRP, hepcidin, and liver iron concentrations. Serum iron concentrations were significantly lower in the LPS (P = 0⋅02) and the LPS + EGCG (P = 0⋅01) than in the positive control group. Compared to the positive control group, spleen iron concentrations were significantly lower in the negative control (P < 0⋅001) but not with both LPS groups. SAA concentrations were significantly lower in the LPS + EGCG group compared to LPS alone group. EGCG reduced SAA concentrations but did not affect hepcidin or improve serum iron concentration or other iron markers.

High ambient temperature is associated with decreasing growth rate, egg production, feed efficiency, nutrient utilisation, egg quality and is a major problem resulting in extensive economic losses in poultry. Poultry reared under heat stress may exhibit various metabolic disorders caused by a chronic state of oxidative stress and inflammation. Recently, nuclear factor-erythroid 2-related factor 2 (Nrf2) has emerged as an agent that plays a significant role in cellular protection against oxidative stress and inflammation. The nuclear factor kappa-B (NF-κB) signalling pathway has been associated with enhanced inflammatory response and its activation has been significantly correlated with heat stress. These transcription factors when activated can regulate antioxidant and anti-inflammatory cellular responses leading to the expression of detoxifying enzymes. Studies have shown that NF-κB and Nrf2 expression can be modulated by several factors, such as bioactive compounds. Green tea contains many polyphenolic antioxidants including the catechin, epigallocatechin-3-gallate (EGCG). As bioactive compounds, supplementing EGCG in poultry diets may improve antioxidant status in poultry. EGCG modulates signalling pathways including the NF-κB and Nrf2 that regulate antioxidant and anti-inflammatory responses. This review aims to discuss the evidence to justify a recommendation of EGCG in heat stressed poultry as a non-pharmacological option to activate the NF-κB and Nrf2 pathways.