Involvement of lipoic acid in plasma metabolites, hepatic oxygen consumption, and metabolic response to a β-agonist in broiler chickens

Abstract

The present study was conducted to determine the role of α-lipoic acid (LA) in plasma metabolites, hepatic O2 consumption, and β-adrenergic response in broilers. In Expt 1, 12-d-old female broiler chicks were divided into three dietary groups and fed on diets with or without LA (5 or 50 mg/kg) until 4 or 6 weeks of age, as a 2 × 3 factorial arrangement. The dietary LA had no effect on growth rates (body weight, abdominal fat, breast muscle, and liver). The higher level of LA increased plasma non-esterified fatty acid and decreased plasma triacylglycerol concentrations only at 6 weeks of age. A 42 % increase in hepatic respiration was observed in the 4-week-old chickens given 50 mg LA/kg diet. In Expt 2, 3-d-old female broiler chicks were treated with or without dietary LA at 50 mg/kg. At 30 and 31 d old, isoproterenol (2 mg/kg body weight per h) was continuously infused into a wing vein for 2 h, and changes in plasma glucose, triacylglycerol, and non-esterified fatty acid concentrations were analysed. Isoproterenol increased plasma glucose over basal levels maximally at 60 min. Furthermore, the glucose increase in the LA-treated chickens was 35% greater than that of the controls at this time. Plasma non-esterified fatty acid and triacylglycerol concentrations were decreased by the isoproterenol infusion, regardless of LA administration. Therefore, the present study suggests that dietary LA has repartitioning effects on energy metabolism in chickens (although this depends on age-related metabolic state) and is a possible facilitator in the β-adrenergic response of plasma glucose to a β-agonist.

Selective deposition of dietary α-Lipoic acid in mitochondrial fraction and its synergistic effect with α-Tocoperhol acetate on broiler meat oxidative stability

“…The results obtained in the present study were consistent with previously reported results [25]. Similar findings were reported that ALA supplementation to a control diet decrease in body weight gain [26]. …”

Dietary Alpha Lipoic Acid Improves Body Composition, Meat Quality and Decreases Collagen Content in Muscle of Broiler Chickens

“…These differences could also be explained by the much lower ALA doses used in our study. In fact, similar observations had been reported by others (Hamano et al, 1999; Hamano et al, 2002) which showed that 0 to 100 mg/kg of ALA did not inhibit muscle growth, but reduced body fat deposition.…”

Effects of dietary lipoic acid on plasma lipid,in vivoinsulin sensitivity, metabolic response to corticosterone andin vitrolipolysis in broiler chickens

“…Furthermore, in chickens, the influence of ALA administration on hormonal actions remains unclear. Hence, the present author initially found that ALA facilitated hyperglycaemic and lipolytic responses to an intravenous infusion of isoproterenol, a b-adrenergic agonist (Hamano et al 1999(Hamano et al , 2000.…”

“…In domestic animals, however, there are few observations on the effects on glucose and lipid metabolisms. In broiler chickens, the author has found that the metabolic response of lipids to dietary ALA administration depends on the agerelated metabolic state (Hamano et al 1999) and that simultaneous increments in both plasma NEFA and triacylglycerol, an interesting response, occurred when the level of administration rose (Hamano, 2002). Khamaisi et al (1999) also observed an increased plasma NEFA level from ALA administration in rats and suggested that this resulted from reduced hepatic fatty acid oxidation.…”