The role of lipoic acid in the protection against of metallic pollutant effects in the shrimp Litopenaeus vannamei (Crustacea, Decapoda)

Abstract

The effects of cadmium (Cd) and arsenic (As), dosed alone or in combination have been poorly investigated in crustaceans. Besides, it is not known if dietary supplementation of exogenous antioxidants, like lipoic acid (LA), might prevent or even reverse toxic effects of Cd and As. The objective of the present study was to evaluate the role of lipoic acid in modulating biochemical responses after Cd and As exposures in Litopenaeus vannamei. Muscle from shrimp exposed to Cd alone or Cd+As showed a decrease in glutathione (GSH) levels, while the pre-treatment with LA reversed this situation. In this tissue, the pre-treatment with LA also induced an increase in glutathione-S-transferase (GST) activity in all groups. In hepatopancreas it was observed a marked accumulation of Cd and As, a decrease in the reactive oxygen species (ROS) concentration in response to Cd exposure alone (-LA); concomitant in the same group it was observed an increment of metallothionein-like content. As exposure induced an increase in GSH levels but LA reversed this increase. Also, LA showed to increase the GST activity in all groups treated. Besides, in this organ LA showed to augment total antioxidant competence. Obtained results indicate that LA can be used as a chemo-protectant against oxidative insults in shrimp.

Antioxidant and oxidative damage responses in different organs of Pacific white shrimpLitopenaeus vannamei(Boone, 1931) reared in a biofloc technology system

“…In L. vannamei shrimp, Lobato et al (2013) found higher TBARS levels in the hepatopancreas compared to the muscle. In the present study, some differences were observed between the gills, hepatopancreas and muscle of L. vannamei.…”

The effect of diet enriched with lipoic acid in the accumulation and metabolization of metals in different organs of Litopenaeus vannamei

“…Arsenic exposure also affected reproduction in zebrafish (Boyle et al, ) and osmoregulation capacity in tilapia (Hwang & Tsai, ) as well as oxidative stress (Sarkar, Mukherjee, Chattopadhyay, & Bhattacharya, ). Although information about the combined effect of Cd and As in aquatic organisms was limited in muscle and hepatopancreas of L. vannamei, a mixture of these metals did not alter the accumulation capacity of these tissues when compared with groups exposed singly to one kind of metal (Lobato et al, ). Also, Doganlar, Doganlar, Muranli, and Guner () observed in zebrafish that the exposure to a high concentration mixture of Cd and As (50 and 100 ppb, respectively) caused a carcinogenic effect.…”

“…The final concentration used in this study was of 1 mg/L of each metal (alone or in combination) during 48 hr. The concentration of each metal was based on Lobato et al () study. Each treatment was performed in duplicate.…”

“…In fact, part of Lagoon Patos, located nearby of Rio Grande city (southern Brazil) has been shown to be contaminated with cadmium and arsenic, due mostly to anthropogenic activities (Mirlean & Roisenberg, ). Lobato et al () showed that L. vannamei exposed to cadmium (Cd) and/or arsenic (As), incorporated and accumulated these metals in the hepatopancreas, inducing a pro‐oxidant situation. Once aquatic organisms have incorporated and accumulated metals in their tissues, the final consumer can be put at risk when ingesting these animals because the food is a significant route of exposure to contaminants (Abdel‐Tawwab, El‐Sayed, & Monier, ; Abdel‐Tawwab, El‐Sayed, & Shady, ).…”

“…Cd exposure induces oxidative stress, histological changes and molecular damages in aquatic organisms, including L. vannamei (Chuang et al, ; Yu et al, ). Other studies evaluating the effect of Cd in L. vannamei, showed that this metal increases glutathione‐ S ‐transferase (GST) activity and metallothionein‐like protein levels, indicating a pro‐oxidant condition (Lobato et al, ). In humans, Cd exposure is associated with damages in respiratory, neurological and renal systems, as well as with the development of prostate and breast cancers.…”