Endocrine Abstracts

Ghrelin is a circulating growth hormone-releasing and appetite-inducing brain–gut peptide. It needs to be acylated on its serine-3 with octanoate for its endocrine actions. The acyl-transferase that catalyses ghrelin octanoylation has been recently identified and named GOAT (ghrelin O-acyltransferase), which is coded by the MBOAT4 gene. This study aimed to investigate GOAT expression in human. The distribution of GOAT mRNA expression was studied in various human tissues using classical and real time reverse transcription and polymerase chain reaction. GOAT expression was found in all tissues studied (stomach, adrenal, breast, right and left colon, duodenum, jejunum, ileum, fat, fallopian tube, gallbladder, lymph node, lymphocyte cell line, kidney, liver, lung, muscle, myocardium, pituitary, oesophagus, pancreas, ovary, placenta, prostate, testis, spleen, and thyroid). The widespread expression of GOAT corresponds to the widespread distribution of ghrelin expression. GOAT expression was higher compared to other tissues (except in the spleen and lung) in stomach and gut, the major ghrelin-secreting tissues, and in the pituitary, in which ghrelin is known to have autocrine and paracrine effects. Identification of GOAT expression and distribution in human will further facilitate the search for inhibitors that can be an effective therapy for diet-induced obesity and type 2 diabetes.