Endocrine Abstracts

Background: The prolactin/vasoinhibin axis constitutes a novel endocrine axis in which the generation, secretion, and actions of the pituitary hormones prolactin and vasoinhibins are under control of the hypothalamus, the pituitary gland, and of regulators in the target tissue microenvironment. Vasoinhibins are generated in the pituitary gland and in multiple target tissues through proteolytic cleavage of prolactin; it is not known wether they are also produced in the circulat...

Background: Full-length human prolactin (protein data bank identification P01236), the precursor of vasoinhibins, is structurally classified as a class-I helical cytokine with a four-helix bundle core and only a minimal degree of dark regions. Experimental data on the solution structure of vasoinhibins are not available.Methods: A recombinant, human vasoinhibin with a molecular mass of 16.7 kDa, comprising amino acids 29-176 of prolactin, was expressed i...

With preterm regression of the hyaloid vascular system, the human vitreous becomes devoid of blood vessels and maintains an avascular, transparent state throughout life. However, diseases of the developing and mature retina, such as retinopathy of prematurity or proliferative diabetic retinopathy (PDR), often result in the invasion of blood vessels into the vitreous, with a risk of causing vitreous hemorrhage, retinal detachment and, consequently, loss of vision or blindness. ...

Circulating levels of the antiangiogenic protein vasoinhibin (16 kDa PRL), a fragment of prolactin, are of interest in vasoproliferative retinopathies, preeclampsia, and peripartum cardiomyopathy, but are unknown due to the lack of a quantitative assay. Here, human serum samples were investigated for the concentration and bioactivity of vasoinhibin using a novel enzyme-linked immunosorbent assay (ELISA) for human vasoinhibin employing an anti-vasoinhibin monoclonal antibody, a...

Vasoinhibin, historically also known as 16K PRL, is a peptide hormone with antiangiogenic, antivasodilatatory, and antivasopermeability effects generated by proteolytic cleavage of prolactin (PRL). The discovery of its role in diabetic retinopathy and peripartum cardiomyopathy led to the development of new pharmacological treatments and their evaluation in clinical interventional trials (ClinicalTrials.gov Identifier: NCT03161652 and NCT00998556). Recent insights into the func...