Physiological responses and HSP70 mRNA expression of GIFT strain of Nile tilapia (Oreochromis niloticus) under cold stress

Abstract

An investigation on the physiological responses and HSP70 expression under cold stress was conducted on Genetically Improved Farmed Tilapia (GIFT) strain of Nile tilapia (Oreochromis niloticus). Tilapia were acclimated at 28°C as control and then the water temperature was reduced from 28°C to 15°C at a rate of 1°C h À1 , and serum biochemical indices, antioxidant enzymes and expression of HSP70 mRNA were analysed on days 0, 0.5, 1, 2, 3 and 5 after exposure to 15°C. The concentration of serum K, Na, Cl and Ca concentration showed instability during cold stress. Glucose rapidly increased on day 0 followed by a declining trend. Triglyceride, cholesterol, low density lipoprotein-cholesterol significantly decreased and high density lipoproteincholesterol showed instability during cold stress. Aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase activities were prominently elevated under cold stress. Superoxide dismutase and catalase activities showed a remarkable rise on day 0.5 under cold stress, and gradually decreased thereafter. HSP70 mRNA level significantly increased both in liver and muscle under cold stress, especially on days 0.5 and 1. These results suggest that cold influences several physiological responses of tilapia, and the cold resistance and cold tolerance of tilapia will benefit from the enhancement of antioxidant enzymes activities and upregulated HSP70 mRNA expression.

Improving low‐temperature stress tolerance of tilapia, Oreochromis niloticus: A functional analysis of Astragalus membranaceus

“…In the present study, SOD activity in the liver first decreased and then increased slightly with decreasing water temperature, whereas MDA content increased. The results of the current study were similar to previous studies on tilapia (Shi et al, ), swimming crab, Portunus trituberculatus (Meng, Liu, Li, Gao, & Chen, ), and puffer fish (Cheng et al, ). To date, many studies have confirmed that A. membranaceus and its extracts have significant antioxidant activities (Jia et al, ; X. L. Jiang et al, ; M. Li et al, ).…”

Cold effect analysis and screening of SNPs associated with cold‐tolerance in the olive flounder Paralichthys olivaceus

“…The HSP70/hsp70 expression in O. niloticus significantly increased at first under cold stress (Hassan, 2017;Shi et al, 2015) similar to the upregulation of flounder hsp70 expression in this study. Previous studies also demonstrated that HSP70 synthesis in fish was enhanced under low temperature (Shi et al, 2015;Weber & Bosworth, 2005).…”

“…Under cold stress, physiological and histological responses of fish are the first to be considered, but the latter is rarely reported. In several fishes, such as Oreochromis niloticus and Albula vulpes , cold elevated prominently superoxide dismutase and catalase activities, and lactate concentration (Shi et al, ; Szekeres et al, ). These physiological responses need energy supplying.…”

“…In several fishes, such as Oreochromis niloticus and Albula vulpes, cold elevated prominently superoxide dismutase and catalase activities, and lactate concentration (Shi et al, 2015;Szekeres et al, 2014).…”

“…Heat shock protein 70 (HSP70) was found to be important in fish thermal stress (Dalvi, Pal, Tiwari, & Baruah, 2012) and cold shock. Shi et al (2015) and Weber and Bosworth (2005) demonstrated that HSP70 synthesis in fish was enhanced by low temperature. MRNA-stabilizing proteins like Ybox binding protein 1 (YB-1, YBX1), a member of cold shock domain containing proteins, is indispensable for cold adaptation in microbes and plants (Eliseeva, Kim, Guryanov, Ovchinnikov, & Lyabin, 2011;Sasaki & Imai, 2011).…”