Effects of starvation on energy metabolism and crustacean hyperglycemic hormone (CHH) of the Atlantic ghost crab Ocypode quadrata (Fabricius, 1787)

Abstract

Ocypode quadrata, a crab species found in sandy beaches along the western Atlantic coast, spends the winter months underground without feeding. The main objective of this work was to determine whether O. quadrata is naturally adapted to food deprivation for a period of time. The effects of starvation on the energy metabolism and the expression levels of crustacean hyperglycemic hormone (CHH), known to have an adaptive role in response to many types of environmental stresses, were investigated. First, we isolated the full-length cDNA sequence of OcqCHH and localized the cells producing CHH neuropeptide in eyestalk ganglia by immunostaining. Second, the levels of OcqCHH transcripts were determined in the fed and starved (15 days) intermolt crabs using qRT-PCR assay. The concentration of carbohydrate and lipids in the hemolymph, muscle and hepatopancreas was measured. OcqCHH cDNA sequence has the typical structure of CHHs, and its expression did not change by starvation. Starvation decreased hemolymphatic glucose, muscular glycogen and hepatopancreatic lipids. This implies that hepatopancreas lipolysis followed by β-oxidation, hepatopancreas gluconeogenesis and muscular glycogenolysis may be responsible for the energy requirements of O. quadrata during nutritional stress. Taken together, these results suggest that O. quadrata may be adapted to nutritional deprivation for an extended period of time.