Review: Vaspin (SERPINA12) Expression and Function in Endocrine Cells

Abstract

Proper functioning of the body depends on hormonal homeostasis. White adipose tissue is now known as an endocrine organ due to the secretion of multiple molecules called adipokines. These proteins exert direct effects on whole body functions, including lipid metabolism, angiogenesis, inflammation, and reproduction, whereas changes in their level are linked with pathological events, such as infertility, diabetes, and increased food intake. Vaspin-visceral adipose tissue-derived serine protease inhibitor, or SERPINA12 according to serpin nomenclature, is an adipokine discovered in 2005 that is connected to the development of insulin resistance, obesity, and inflammation. A significantly higher amount of vaspin was observed in obese patients. The objective of this review was to summarize the latest findings about vaspin expression and action in endocrine tissues, such as the hypothalamus, pituitary gland, adipose tissue, thyroid, ovary, placenta, and testis, as well as discuss the link between vaspin and pathologies connected with hormonal imbalance.

Keywords: adipose tissue; endocrine cells; hypothalamus; ovary; pancreas; pituitary; placenta; testis; thyroid; vaspin.

Figure 1

Summary of mechanism of vaspin action. Vaspin (10.2210/pdb4IF8/pdb) and GRP78 structures (10.2210/pdb3LDL/pdb) based on the Protein Data Bank. PRKAA1-AMP-activated kinase; MAP3/1-mitogen-activated kinase; AKT-protein kinase B; STAT3-Janus kinase; NFkB- nuclear factor kappa B; ↑—increase; ↓—decrease; ?—data limitation.

Figure 2

Vaspin endocrine cell expression and its regulation in rodents (A), and human and domestic animals (B). PCOS—polycystic ovarian syndrome; GH—growth hormone; IGF1—insulin-like growth factor type 1; FSH—follicle-stimulating hormone; LH—luteinizing hormone; P4—progesterone; E2—oestradiol; T—testosterone; PG—prostaglandin; ↑—increase; ↓—decrease.

Figure 3

Vaspin function in endocrine cells. NPY—neuropeptide Y; POMC—proopiomelanocortin; TNFα—tumor necrosis factor; GLUT4—glucose transporter-4; PPAR-γ—peroxisome proliferator-activated receptor γ; IRS-2—insulin receptor substrate 2; C/EBPA—CCAAT/enhancer-binding protein α (C/EBPα) and β (C/EBPβ); P4—progesterone; E2—oestradiol; STAR—steroidogenic acute regulatory protein; CYP11A1—cytochrome P450 family 11 subfamily A member 1; HSD3B—hydroxy-delta-5-steroid dehydrogenase; CYP19A1—cytochrome P450 family 19 subfamily A member 1; BAX—BCL2-associated X; PCNA—proliferating cell nuclear antigen; BCL2—B-cell lymphoma 2; PTGER—prostaglandin E receptor; PG—prostaglandin; VEGFA—vascular endothelial growth factor; ANGPT1—angiopoietin 1; FGF2—fibroblast growth factor 2; AKT—protein kinase B; NFkB—nuclear factor kappa B; GRP78—78 kDa glucose-regulated protein; PKA—protein kinase A; MAP3/1—mitogen activated kinase; STAT3—Janus kinase; PRKAA1—AMP-activated kinase; CL—corpus luteum; ↑—increase; ↓—decrease; ns—no study.