Lipotropes promote immunobiochemical plasticity and protect fish against low-dose pesticide-induced oxidative stress

Abstract

An experiment was conducted to evaluate the role of different lipotropes in modulating immunity and biochemical plasticity under conditions of sublethal low-dose pesticide-induced stress in fish. Labeo rohita fish fingerlings were divided in two sets with one set of fish continuously exposed to low-dose endosulfan (1/10th of 96-h LC 50 ) for 21 days, the other was unexposed, and both sets of fish were fed with practical diets supplemented with either 2 % lecithin, 0.5 % betaine, or 0.1 % choline and compared against unsupplemented diet. Low-dose endosulfan exposure had adverse effects (P<0.05/P<0.01) on hematological profile (erythrocyte count, hemoglobin, and hematocrit), serum protein (total protein, albumin, and globulin) and lipid profile (cholesterol and triglyceride), anti-oxidative status (ascorbic acid content of muscle, liver, brain, and kidney and activity of anti-oxidative enzymes: catalase and superoxide dismutase), neurotransmission (acetylcholinesterase activity in muscle and brain), immunological attributes (WBC count, albumin to globulin ratio, phagocytic activity, and serum cortisol), and metabolic plasticity as revealed from enzyme activities (muscle lactate dehydrogenase, liver and kidney glucose-6-phosphatase dehydrogenase-G6PDH activity). Dietary lipotropes prevented these effects completely or partially and the effects were lipotrope dependent. Kinetics (maximum velocity value V max , catalytic efficiency and Michaelis constant K m ) of G6PDH enzyme from crude extracts of liver and kidney indicated inhibition due to endosulfan but lipotropes could protect enzyme and showed a stabilizing effect. The supplements also helped maintain integrity of histoarchitecture of the hepatocytes in endosulfan-exposed fish to a great extent. Feeding lipotropes to fish reared in endosulfan-free water also improved hematological and serum protein and lipid profiles and were immunostimulatory. In conclusion, dietary lipotropes, especially betaine and lecithin at the levels used, improve erythropoiesis, serum protein and lipid profile, anti-oxidant status, immunocompetence, neurotransmission, and protect the livers of L. rohita fingerlings even when continuously exposed to low-dose endosulfan.

Dietary Pyridoxine Protects against Stress and Maintains Immunohaematological Status in Chanos chanos Exposed to Endosulfan

“…The neurotransmitter, acetylcholine hydrolysing into choline and acetic acid and responsibility of this phenomenon fully depend on acetylcholine esterase. It is one of the most important indices in toxicity studies because it catalyses hydrolysis of acetylcholine at the synaptic junctions, thereby facilitating the nerve impulse transmission from one cholinergic neuron to the others [49]. In the present study, the brain AChE activity in C. chanos exposed to endosulfan was inhibited, suggesting similar disrupting cholinergic neurotransmission through inhibition of AChE [35].…”

Dietary zinc potentiates thermal tolerance and cellular stress protection ofPangasius hypophthalmusreared under lead and thermal stress

“…hypophthalmus have been significantly improved with Zn supplementation might be due to stimulates cholinergic activity in certain brain regions which may play a role in the therapeutic effect of Zn micronutrient to improved AChE activities. Similar results were found in case of lecithin (Kumar, Jadhao, Chandan, Akhlak & Rana, ; Kumar, Jadhao, Chandan & Rana, ; Muthappa et al., ) and pyridoxine (Kumar, Ambasankar, Krishnani, Bhushan, et al., ) fed to Labeo rohita and Chanos chanos respectively. In our earlier study, lecithin and pyridoxine were responsible for enhancement of thermal tolerance in C. chanos and also take important role in improvement of acetyl cholinesterase activities during end of the LTmin and LTmax (Kumar, Ambasankar, Krishnani, Kumar, et al., ; Kumar et al., ; Kumar, Minhas, et al., ).…”

Dietary lecithin potentiates thermal tolerance and cellular stress protection of milk fish (Chanos Chanos) reared under low dose endosulfan-induced stress

“…Our previous study (Kumar et al, 2011b) found reduction in brain AChE activity in Oreochromis mossambicus when exposed to endosulfan for 96 h and also Kumar et al, 2012 reported that supplementation of lecithin in the diet of L. rohita resulted in higher AChE activity. To corroborate our finding Muthappa et al (2013) reported that exposure to endosulfan resulted in a significant reduction in AChE activity in L. rohita and supplementation of lecithin resulted in significantly higher AChE activity. Gupta et al (2014) reported that levan supplementation in the diet improved AChE activities in common carp exposed to fipronil.…”