The immunosuppressive, growth-hindering, hepatotoxic, and oxidative stress and immune related-gene expressions-altering effects of gibberellic acid in Oreochromis niloticus: A mitigation trial using alpha-lipoic acid

Journal Article

2023

Published in: www.elsevier.com/locate/pest

Plant growth regulators Lipoic acid Immunosuppression Apoptosis Heat shock protein 70 mRNA profiling

This study aimed to examine the effects of gibberellic acid (GBA) on growth, hemato-biochemical parameters
related to liver functions, digestive enzymes, and immunological response in Oreochromis niloticus. Besides, the
probable underlying mechanisms were explored by assessing antioxidant, apoptotic, and immune-related gene
expression. Furthermore, the likelihood of restoration following alpha-lipoic acid (LIP) dietary supplementation
was explored. The fish (average initial weight 30.75 ± 0.46) were equally classified into four groups: the control
group, the LIP group (fed on a basal diet plus 600 mg/kg of LIP), the GBA group (exposed to 150 mg GBA/L), and
the GBA + LIP group (exposed to 150 mg GBA/L and fed a diet containing LIP and GBA) for 60 days. The study
findings showed that LIP supplementation significantly reduced GBA's harmful effects on survival rate, growth,
feed intake, digestive enzymes, and antioxidant balance. Moreover, the GBA exposure significantly increased
liver enzymes, stress markers, cholesterol, and triglyceride levels, all of which were effectively mitigated by the
supplementation of LIP. Additionally, LIP addition to fish diets significantly minimized the histopathological
alterations in the livers of GBA-treated fish, including fatty change, sharply clear cytoplasm with nuclear
displacement to the cell periphery, single-cell necrosis, vascular congestion, and intralobular hemorrhages. The
GBA-induced reduction in lysozyme activity, complement C3, and nitric oxide levels, together with the downregulation
of antioxidant genes (cat and sod), was significantly restored by dietary LIP. Meanwhile, adding LIP to
the GBA-exposed fish diets significantly corrected the aberrant expression of hsp70, caspase- 3, P53, pcna, tnf-a,
and il-1β in O. niloticus liver. Conclusively, dietary LIP supplementation could mitigate the harmful effects of GBA
exposure on fish growth and performance, physiological conditions, innate immunity, antioxidant capability,
inflammatory response, and cell apoptosis.

• Publication Work Type: original article
• Publisher Name: Elsevier
• Publishing City: Riyadh
• Volume Number: 198
• Issue Number: 105725
• Magazine \ Newspaper: Pesticide Biochemistry and Physiology
• Pages: 1-11