LHRH (GNRH) was first isolated in the mammalian hypothalamus and shown to be the primary regulator of the reproductive neuroendocrine axis comprising of the hypothalamus, pituitary and gonads. LHRH acts centrally through its initiation of pituitary gonadotrophin release. Since its discovery, this form of LHRH (LHRH-I) has been shown to be one of over 20 structural variants with a variety of roles in both the brain and peripheral tissues. LHRH-I is processed by a zinc metalloendopeptidase EC 3.4.24.15 (EP24.15) that cleaves the hormone at the fifth and sixth bond of the decapeptide (Tyr5-Gly6) to form LHRH-(1–5). We have previously reported that the auto-regulation of LHRH-I (GNRH1) gene expression and secretion can also be mediated by itself and its processed peptide, LHRH-(1–5), centrally and in peripheral tissues. In this review, we present the evidence that EP24.15 is the main enzyme of LHRH metabolism. Following this, we look at the metabolism of other neuropeptides where an active peptide fragments is formed during degradation and use this as a platform to postulate that EP24.15 may also produce an active peptide fragment in the process of breaking down LHRH. We close this review by the role EP24.15 may have in regulation of the complex LHRH system.
Anti-N-methyl-D-aspartate receptor encephalitis is an autoimmune disorder that can occur as a paraneoplastic phenomenon related to ovarian teratomas. It is a serious but reversible condition with improved outcomes following prompt tumor removal. We report two cases from our recent experience. In the first case a small poorly described lesion, confirmed as a teratoma only at histology, was managed by laparoscopic oopohorectomy. In the second case a large teratoma was managed by laparoscopic cystectomy. Postoperatively both women made a good recovery. Gynecologists may be called upon to perform ovarian surgery outside of normal surgical indications, in young women who will often lack capacity to consent. Fertility-sparing ovarian cystectomy is possible in some cases, but will be challenging for small deeply buried tumors. Blind bilateral oophorectomy has been performed successfully in extreme cases. Information of the benefit of ovarian surgery will be essential to the surgeon during preoperative counseling.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.