Effects of vitamin C and folic acid supplementation on serum paraoxonase activity and metabolites induced by heat stress in vivo

This study investigated the effects of vitamin C (L-ascorbic acid) and folic acid supplementation n the levels of enzymes activities such as paraoxonase (PON1) and arylesterase and metabolites in he plasma of heat-stressed Japanese quails (Coturnix coturnix japonica) kept at 34°C. A total of 150 apanese quails (10 days old) were randomly assigned to five treatment groups, with three replicates f 10 birds each. The birds, which were kept at 34°C (09.00 to 17.00; for 8 hours) were fed either a asal diet (high-temperature basal diet, HS group) or the basal diet supplemented with either 250 mg f L-ascorbic acid/kg of diet (Vit C group), 1 mg of folic acid/kg of diet (FA group), or 250 mg of -ascorbic acid plus 1 mg of folic acid/kg of diet (Vit C FA group), whereas birds kept at 22°C were ed a basal diet (thermo-neutral-basal diet, TN group). Supplemental vitamin C and folic acid ignificantly increased paraoxonase, arylesterase, creatine kinase, lactic dehydrogenase, and alkaline hosphatase activities compared with the HS group. Serum activities of aspartate aminotransferase nd alanine aminotransferase were not influenced by dietary vitamin C or folic acid (P 0.05). Serum holesterol, triglyceride, high density lipoprotein (HDL)–cholesterol, and glucose concentrations ecreased, whereas total protein and albumin concentrations increased with dietary vitamin C and olic acid supplementation (P 0.05) compared with the HS group. However, the combination of itamin C and folic acid provided the greatest results. Serum values were also greatest for PON1 and rylesterase and lowest for cholesterol, trygliceride, HDL-cholesterol and glucose (P 0.05) for the N group. The results of the study show that, separately or in combination, vitamin C and folic acid upplementation improved increased PON1 and arylesterase; the results also suggest that vitamin C nd folic acid, especially in combination, may offer a potential protective management practice in