The crustacean hyperglycemic hormones (CHH) are pleiotropic neuropeptides controlling diverse processes in the life cycle of crustaceans. In the Pacific white shrimp Litopenaeus vannamei, CHH‐B1 and CHH‐B2 are generated by alternative splicing of the same gene, and the recombinant versions of these peptides have shown differential effects on glucose metabolism and osmoregulation in this species. In this work, we explored the role of both recombinant variants, expressed in yeast Pichia pastoris, on lipid metabolism. The results showed that rCHH‐B1 and rCHH‐B2 injections into eyestalk‐ablated shrimp significantly increased the phospholipid and triglyceride levels in haemolymph and restored free fatty acid levels, suggesting that these CHH variants mobilize lipid reserves in shrimp. The effects on lipids were concomitant to its hyperglycemic activity, suggesting that both variants, in addition to their hyperglycemic activity, have hyperlipidemic functions.

Osmoregulation in crustaceans is under neuroendocrine control by the crustacean hyperglycemic hormones (CHHs), which modify water and ion concentrations in diverse species. Previous studies done by our group suggested that CHH variant B1 (CHH-B1) has effects on the osmoregulatory responses of the Pacific white shrimp Litopenaeus vannamei. For a better understanding of the molecular action mechanisms of CHH-B1 in osmoregulation, in this work, we established the dose-dependent effect of recombinant CHH-B1 on the gene expression of Na+/K+-ATPase (NKA) in gills, in contrast to changes in the osmoregulatory capacity (OC) of bilaterally eyestalk-ablated shrimp under hyper-osmotic conditions. The results indicate that CHH-B1 regulates the OC of shrimp during hypo-regulation by modulating Na+/K+-ATPase at a transcriptional level. Our results suggest that CHH has a direct participation in the control of osmo-ionic regulation mechanisms, not only in L. vannamei but in crustaceans in general.