Protective efficacy of Nigella sativa seeds against diethyl phthalate induced growth retardation, oxidative stress and histo-biochemical damages in Labeo rohita

Abstract

The current study assessed the ameliorative potential of Nigella sativa seeds against diethyl phthalate (DEP) induced growth retardation, oxidative stress and histo-biochemical changes in Labeo rohita (rohu) fingerlings. N. sativa, a medicinal plant containing several pharmacological properties, was incorporated into three diets at 0%, 1%, and 2.5% levels, prepared by mixing N. sativa seeds with the basal diet. The median lethal concentration of DEP to rohu was 4.38 mg L−1 for 96th hour. Three hundred fingerlings (8.502 ± 0.009 g) were exposed to a sub-lethal concentration of 0.51 mg L−1 (1/10th of LC50) DEP, with or without N. sativa for 7, 14, 21, and 28 days. The results revealed that rohu exposed to DEP alone has significantly decreased growth rate, as opposed to rohu exposed to DEP in combination with N. sativa, which demonstrated markedly improved growth rates. A significant decrease in muscles protein contents of DEP-treated rohu was also noted. DEP exposure also inhibited the antioxidant enzymes (catalase, glutathione-S-transferase and glutathione peroxidase) activities in all of the studied tissues (liver, kidney, gills and brain). Moreover, DEP exposure significantly increased lipid peroxidation levels, whereas glutathione (GSH) levels decreased in all of the studied rohu tissues in a time-dependent manner. Where DEP exposure has been found to enhance alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, urea, and creatinine levels; a significant reversal in the levels of these enzymes was noted in N. sativa supplemented rohu. Histological studies of the liver, kidney, and gills indicated that N. sativa supplementation in rohu provides beneficial protective defenses against DEP-induced toxicity.