Correction: Szymanska et al. The Effect of Visfatin on the Functioning of the Porcine Pituitary Gland: An In Vitro Study. 2023, 12, 2835.

In the original publication [...

The adipokine profile in the plasma and anterior pituitary of pigs during the estrous cycle.

Adipokines play crucial roles in both reproductive and energy metabolic processes. This study aimed to compare the hormonal plasma profile of adiponectin, apelin, vaspin, chemerin, resistin, visfatin, and adipolin, and the expression of their receptors in the anterior pituitary (AP) between normal-weight Large White (LW) and fat Meishan (MS) pigs during different phases of the estrous cycle. We measured adipokine levels in the plasma and assessed their gene expression in the AP.

In vitro effect of visfatin on endocrine functions of the porcine corpus luteum.

Previously, we demonstrated the expression of visfatin in porcine reproductive tissues and its effect on pituitary endocrinology. The objective of this study was to examine the visfatin effect on the secretion of steroid (P, E) and prostaglandin (PGE, PGF), the mRNA and protein abundance of steroidogenic markers (STAR, CYP11A1, HSD3B, CYP19A1), prostaglandin receptors (PTGER2, PTGFR), insulin receptor (INSR), and activity of kinases (MAPK/ERK1/2, AKT, AMPK) in the porcine corpus luteum. We noted that the visfatin effect strongly depends on the phase of the estrous cycle: on days 2-3 and 14-16 it reduced P, while on days 10-12 it stimulated P.

The Effect of Visfatin on the Functioning of the Porcine Pituitary Gland: An In Vitro Study.

Visfatin (VIS), also known as nicotinamide phosphoribosyltransferase (NAMPT), is the rate-limiting enzyme in the biosynthesis of nicotinamide adenine dinucleotide (NAD+). Recently, VIS has been also recognized as an adipokine. Our previous study revealed that VIS is produced in the anterior and posterior lobes of the porcine pituitary.

Expression and in vitro effect of phoenixin-14 on the porcine ovarian granulosa cells.

Phoenixin-14 (PNX-14) regulates energy metabolism via the G protein-coupled receptor 173 (GPR173); elevated plasma levels have been described in patients with polycystic ovary syndrome. The aims were to investigate the ovarian expression of PNX-14/GPR173 and the in vitro effect of PNX-14 on granulosa cells (Gc) function. Transcript and protein levels of PNX-14/GRP173 were analysed by real-time PCR, western blot and immunohistochemistry in the porcine ovarian follicles at days 2-3, 10-12 and 16-18 of the oestrous.

Plasma level of omentin-1, its expression, and its regulation by gonadotropin-releasing hormone and gonadotropins in porcine anterior pituitary cells.

Omentin-1 (OMNT1) is an adipokine involved in the regulation of energy metabolism, insulin sensitivity, and reproduction. The present study was the first to investigate the plasma levels and expression of OMNT1 in the anterior pituitary (AP) gland on days 2-3, 10-12, 14-16, and 17-19 of the estrous cycle of normal-weight Large White (LW) and fat Meishan (MS) pigs. Next, we determined the effect of GnRH, LH, and FSH on the OMNT1 levels in cultured AP cells.

Visfatin in the porcine pituitary gland: expression and regulation of secretion during the oestrous cycle and early pregnancy.

Visfatin is a multifunctional protein which, besides the control of energy homeostasis, seems to be also involved in the regulation of female fertility through the influence on the endocrine hypothalamus-pituitary-gonadal axis, including the pituitary. The aim of this study was to investigate the expression of visfatin mRNA and protein in the anterior (AP) and posterior pituitary lobes of the pig during the oestrous cycle and early pregnancy. In AP, we also examined colocalisation of visfatin with pituitary tropic hormones.

Phoenixin-14 as a novel direct regulator of porcine luteal cell functions†.

Phoenixin is a neuropeptide with a well-established role in the central regulation of reproductive processes; however, knowledge regarding its role in the ovary is limited. One of the main active phoenixin isoforms is phoenixin-14, which acts through G protein-coupled receptor 173. Our research hypothesis was that phoenixin-14 is expressed in porcine corpus luteum and exerts luteotropic action by affecting the endocrine function of luteal cells through G protein-coupled receptor 173 and protein kinase signaling.

Expression of visfatin in the ovarian follicles of prepubertal and mature gilts and in vitro effect of gonadotropins, insulin, steroids, and prostaglandins on visfatin levels.

Recent studies have demonstrated that visfatin participates in the regulation of female reproduction. Due to the lack of data concerning the level of visfatin in the ovarian follicles of pigs, one of the most economically important livestock species, the aim of this study was to investigate the expression and localisation of visfatin and the follicular fluid concentration in the ovarian follicles of prepubertal and mature gilts. We also aimed to examine the in vitro effects of gonadotropins (LH, FSH), insulin, progesterone (P), oestradiol (E), prostaglandin E (PGE) and F (PGF) on visfatin levels.

Resistin as a new player in the regulation of porcine corpus luteum luteolysis: in vitro effect on proliferation/viability, apoptosis and autophagy.

The formation and luteolysis of the corpus luteum (CL) is strictly controlled by many factors. Imbalance between proliferation and apoptosis processes leads to deficiency of the luteal phase and infertility. Our previous study showed resistin expression in porcine luteal cells and an inhibitory effect on progesterone synthesis.

Synergistic Action of MCL-1 Inhibitor with BCL-2/BCL-XL or MAPK Pathway Inhibitors Enhances Acute Myeloid Leukemia Cell Apoptosis and Differentiation.

Acute myeloid leukemia (AML) is a hematological malignancy characterized by excessive proliferation of abnormal myeloid precursors accompanied by a differentiation block and inhibition of apoptosis. Increased expression of an anti-apoptotic MCL-1 protein was shown to be critical for the sustained survival and expansion of AML cells. Therefore, herein, we examined the pro-apoptotic and pro-differentiating effects of S63845, a specific inhibitor of MCL-1, in a single-agent treatment and in combination with BCL-2/BCL-XL inhibitor, ABT-737, in two AML cell lines: HL-60 and ML-1.

Expression and regulation of visfatin/NAMPT in the porcine corpus luteum during the estrous cycle and early pregnancy.

Visfatin/NAMPT creates a hormonal link between energy metabolism and female reproduction. A recent study documented visfatin expression in the ovary and its action on follicular cells; however, the expression of visfatin in luteal cells is still unknown. The aim of this study, therefore, was to investigate the transcript and protein expression of visfatin as well as its immunolocalization in the corpus luteum (CL) and to examine the involvement of extracellular signal-regulated kinases (ERK1/2) in the regulation of visfatin level in response to LH, insulin, progesterone (P), prostaglandin E (PGE) and F (PGF).

Concentration of Polycyclic Aromatic Hydrocarbons (PAHs) in Human Serum and Adipose Tissues and Stimulatory Effect of Naphthalene in Adipogenesis in 3T3-L1 Cells.

Polycyclic aromatic hydrocarbons (PAHs) are one of the most prevalent classes of environmental pollutants. Some evidence shows that PAHs could be involved in human obesity. However, little is known about the distribution patterns of PAHs in human adipose tissue (AT) and the role of PAHs on adipogenesis/lipogenesis.

The Apelinergic System: Apelin, ELABELA, and APJ Action on Cell Apoptosis: Anti-Apoptotic or Pro-Apoptotic Effect?

The apelinergic system comprises two peptide ligands, apelin and ELABELA, and their cognate G-protein-coupled receptor, the apelin receptor APJ. Apelin is a peptide that was isolated from bovine stomach extracts; the distribution of the four main active forms, apelin-36, -17, -13, and pyr-apelin-13 differs between tissues. The mature form of ELABELA-32 can be transformed into forms called ELABELA-11 or -21.

Levels of spexin and its receptors GALR2 and GALR3 in the hypothalamus and ovary of letrozole-induced polycystic ovary syndrome in rats.

Spexin (SPX) is a newly identified neuropeptide, a natural ligand for the galanin receptors (GALR) 2/3, which is involved in maintaining physiological functions including female reproduction. One of the most common endocrine disorder in reproductive system is polycystic ovary syndrome (PCOS), however the role of SPX in PCOS is still unknown. The objective of this study was to determine the expression of mRNA and peptide levels of SPX and its receptors GALR2/3 in the hypothalamus and ovary (by real time PCR and Western blot) as well as plasma levels of SPX (ELISA) in letrozole - induced PCOS rats.

Endocrine disruptor chemicals, adipokines and reproductive functions.

The prevalence of adult obesity has risen markedly in recent decades. The endocrine system precisely regulates energy balance, fat abundance and fat deposition. Interestingly, white adipose tissue is an endocrine gland producing adipokines, which regulate whole-body physiology, including energy balance and reproduction.

New insights into cell apoptosis and proliferation: the potential role of vaspin.

Vaspin, also known as visceral adipose tissue-derived serine protease inhibitor; expression of this adipokine has been confirmed in many parts of the body like the hypothalamus, pancreas, thyroid gland, ovaries, placenta, and testes, where it may play a crucial role in osteogenesis, steroidogenesis, the formation of blood vessels, and food intake. In addition, there are many studies supporting an interaction between vaspin and cell proliferation and apoptosis, which are crucial processes for maintaining homeostasis of the body. Vaspin has an anti-apoptotic effect in ovarian cells, osteoblasts, macrophages, aortic endothelial cells, hepatocellular carcinoma cells, and cardiomyocytes.

New Aspects of Corpus Luteum Regulation in Physiological and Pathological Conditions: Involvement of Adipokines and Neuropeptides.

The corpus luteum is a small gland of great importance because its proper functioning determines not only the appropriate course of the estrous/menstrual cycle and embryo implantation, but also the subsequent maintenance of pregnancy. Among the well-known regulators of luteal tissue functions, increasing attention is focused on the role of neuropeptides and adipose tissue hormones-adipokines. Growing evidence points to the expression of these factors in the corpus luteum of women and different animal species, and their involvement in corpus luteum formation, endocrine function, angiogenesis, cells proliferation, apoptosis, and finally, regression.

Apelin, APJ, and ELABELA: Role in Placental Function, Pregnancy, and Foetal Development-An Overview.

The apelinergic system, which includes the apelin receptor (APJ) as well as its two specific ligands, namely apelin and ELABELA (ELA/APELA/Toddler), have been the subject of many recent studies due to their pleiotropic effects in humans and other animals. Expression of these factors has been investigated in numerous tissues and organs-for example, the lungs, heart, uterus, and ovary. Moreover, a number of studies have been devoted to understanding the role of apelin and the entire apelinergic system in the most important processes in the body, starting from early stages of human life with regulation of placental function and the proper course of pregnancy.

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

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.

Expression and role of resistin on steroid secretion in the porcine corpus luteum.

Resistin plays an important role in adipogenesis, obesity, insulin resistance, and reproduction. Previous studies showed resistin action on ovarian follicular cells; however, whether resistin regulates steroid secretion in luteal cells is still unknown. Our aim was first to determine the expression of resistin and its potential receptors (tyrosine kinase-like orphan receptor 1 (ROR1) and toll-like receptor 4 (TLR4)) in the porcine corpus luteum (CL), regulation of its expression, effect on kinases phosphorylation, and luteal steroidogenesis.

Plasma level and expression of visfatin in the porcine hypothalamus during the estrous cycle and early pregnancy.

Visfatin appears to be an energy sensor involved in the regulation of female fertility, which creates a hormonal link integrating the control of energy homeostasis and reproduction. This study evaluates the expression levels of visfatin gene and protein in selected areas of the porcine hypothalamus responsible for gonadotropin-releasing hormone synthesis: the mediobasal hypothalamus (MBH) and preoptic area (POA), and visfatin concentrations in the blood plasma. The tissue samples were harvested from gilts on days 2-3, 10-12, 14-16, and 17-19 of the estrous cycle, and on days 10-11, 12-13, 15-16, 27-28 of pregnancy.

Anti-Apoptotic Effect of Apelin in Human Placenta: Studies on BeWo Cells and Villous Explants from Third-Trimester Human Pregnancy.

Previously, we demonstrated the expression of apelin and G-protein-coupled receptor APJ in human placenta cell lines as well as its direct action on placenta cell proliferation and endocrinology. The objective of this study was to examine the effect of apelin on placenta apoptosis in BeWo cells and villous explants from the human third trimester of pregnancy. The BeWo cells and villous explants were incubated with apelin (2 and 20 ng/mL) alone or with staurosporine for 24 to 72 h.

Adipokines change the balance of proliferation/apoptosis in the ovarian cells of human and domestic animals: A comparative review.

Adipose tissue secretes multiple hormones termed adipokines, which are important regulators of many processes. There are four types of evidence supporting an association between adipokines and female fertility which are effects that occur: centrally at the pituitary; peripherally and locally at the ovary and reproductive tract; directly on the oocyte/embryo and during pregnancy. In this review, there was a focus on the description of adipokines (leptin, apelin, resistin, chemerin, adiponectin, vaspin and visfatin) on ovarian cell proliferation, cell cycle progression and apoptosis in comparison to effects on human and domestic animal ovaries including pigs, cattle and chickens.