Co-administration of zinc for treating and preventing arsenism in common carp Cyprinus carpio: An alternative to avoid physiological and cellular damages

Abstract

Arsenic (As) contamination in water bodies has adverse effects on aquatic organisms. Zinc (Zn), as an important enzyme cofactor and efficient reactive oxygen species scavenger, plays an indispensable role in cellular homeostasis and biological functions. However, there has been less investigation on AsZn interaction in common carp (Cyprinus carpio). We hypothesize that Zn is a candidate for the treatment and prevention of arsenism. In general, feed efficiency, growth performance and organ indices did not significantly differ between the As or/and Zn group and the control groups (p > 0.05). However, arsenite significantly altered the intestinal morphological features and suppressed intestinal tight junction proteins (claudins, occluding, and zonula occludens) as indicated by mRNA and protein levels. Moreover, oxidative stress (malondialdehyde and organic 8-hydroxy-2-deoxyguanosine), inflammatory (nuclear factor kappa-B and pro-inflammatory cytokines) and detoxification parameters (metallothionein) in intestine and liver increased following arsenite exposure (p < 0.05), concomitant with innate immunity suppression (C4 and IgM; p < 0.01). These anomalies led to abnormal lipid metabolism (SREBP-1c pathway; p < 0.01) and endoplasmic reticulum stress (PERK-eIF2α, IRE1α and ATF6; p < 0.01). Overall, As impaired general physiological and cellular functions, and compromised the immune system of carp. Zn2+ restored these alterations, as evidenced by the reduction in inflammation and endoplasmic reticulum stress via the activation of the antioxidant system. Thus, Zn supplementation can be used to treat and prevent arsenism; it is a useful alternative to prevent physiological and cellular damage in the inland culture of carp.