Studies in humans and mice support a role for Makorin RING finger protein 3 (MKRN3) as an inhibitor of gonadotropin-releasing hormone (GnRH) secretion prepubertally, and its loss of function is the most common genetic cause of central precocious puberty in humans. Studies have shown that the gonads can synthesize neuropeptides and express MKRN3/Mkrn3 mRNA. Therefore, we aimed to investigate the spatiotemporal expression pattern of Mkrn3 in gonads during sexual development, and its potential regulation in the functional testicular compartments by gonadotropins.
View Article and Find Full Text PDFAlthough some studies have shown that a high-fat diet (HFD) adversely affects muscle extracellular matrix remodeling, the mechanisms involved in muscle trophism, inflammation, and adipogenesis have not been fully investigated. Thus, we investigated the effects of 8 weeks of paternal resistance training (RT) on gene and protein expression/activity of critical factors involved in muscle inflammation and remodeling of fathers and offspring (offspring exposed to standard chow or HFD). Animals were randomly distributed to constitute sedentary fathers (SF; = 7; did not perform RT) or trained fathers (TF = 7; performed RT), with offspring from mating with sedentary females.
View Article and Find Full Text PDFControlling the inflammatory response to restore tissue homeostasis is a crucial step to maintain tooth vitality after pathogen removal from caries-affected dental tissues. The nuclear peroxisome proliferator-activated receptor beta/delta (PPAR/) is a ligand-activated transcription factor with emerging anti-inflammatory roles in many cells and tissues. However, its expression and functions are poorly understood in human dental pulp cells (hDPCs).
View Article and Find Full Text PDFAims: We investigate the effects of RT on the mechanical function, gene, and protein expression of key factors involved in bone remodeling during aging.
Main Methods: Male rats of 3 and 21 months of age were randomly allocated into four groups (8 per group): young sedentary (YS), young trained (YT), old sedentary (OS), and old trained (OT). RT was performed three times per week (12 weeks).
Background: Beige adipocytes comprise a unique thermogenic cell type in the white adipose tissue (WAT) of rodents and humans, and play a critical role in energy homeostasis. In this scenario, recruitment of beige cells has been an important focus of interest for the development of novel therapeutic strategies to treat obesity. PPARγ activation by full agonists (thiazolidinediones, TZDs) drives the appearance of beige cells, a process so-called browning of WAT.
View Article and Find Full Text PDFIntroduction: Rosiglitazone (RSG) is a synthetic full agonist of transcription factor peroxisome proliferator activated receptor gamma. Previous studies have suggested an anti-inflammatory effect of RSG on lipopolysaccharide-induced pulp inflammation. However, its role in other cellular events related to pulp repair has not been investigated.
View Article and Find Full Text PDFThe Wnt/β-catenin signaling pathway controls several biological processes throughout development and adult life. Dysregulation of Wnt/β-catenin signaling underlies a wide range of pathologies in animals and humans, including cancer in different tissues. In this review, we provide an update of the Wnt/β-catenin signaling pathway and the possible roles of the Wnt/β-catenin signaling in the biology of testis, epididymis and prostate.
View Article and Find Full Text PDFRegulation of Sertoli cell number is a key event to determine normal spermatogenesis. We have previously shown that relaxin and its G-protein coupled receptor RXFP1 are expressed in rat Sertoli cells, and that relaxin stimulates Sertoli cell proliferation. This study examined the mechanisms underlying the mitogenic effect of relaxin in a primary culture of Sertoli cells removed from testes of immature rats.
View Article and Find Full Text PDFThe aim of the present study was to investigate the intracellular signaling events downstream of the classical estrogen receptors (ESRs) and G protein-coupled estrogen receptor 1 (GPER) involved in regulation of proliferation and apoptosis of rat Sertoli cells, in which we have previously described ESR1, ESR2, and GPER. ESRs play a role in Sertoli cell proliferation, and GPER, but not ESRs, plays a role modulating gene expression involved with apoptosis. The present study shows that 17beta-estradiol (E2) and the GPER-selective agonist G-1 rapidly activate phosphatidylinositol 3-kinase (PIK3)/serine threonine protein kinase (AKT) and cyclic AMP response element-binding (CREB) phosphorylation.
View Article and Find Full Text PDFThe aim of the present study was to investigate the activation of rapid signaling events by 17β-estradiol in the rat uterus. 17β-Estradiol induced a rapid increase of total [3H]-inositol phosphate accumulation in the whole uterus and endometrium, but not in the myometrium. The effect of 17β-estradiol in the endometrium was blocked by phospholipase C (PLC) inhibitor (U73122), estrogen receptors antagonist (ICI 182,780), exportin CRM1 inhibitor (leptomycin B) and selective inhibitor of the SRC family of protein tyrosine kinases (PP2).
View Article and Find Full Text PDFThe aim of the present study was to investigate the expression and signaling of the G protein-coupled estrogen receptor 1 (GPER) in cultured immature rat Sertoli cells--in which we have previously described the classical estrogen receptors (ESR1 and ESR2). Expression of GPER in cultured Sertoli cells from 15-day-old rats was detected by RT-PCR and immunoassays. Gper transcripts also were present in testes from 5-, 15-, and 120-day-old rats.
View Article and Find Full Text PDFAlthough the biological effects of thyroid hormones are mediated by nuclear receptors (genomic mechanisms), interactions with receptors associated with the plasma membrane (non-genomic mechanisms) of target cells are not clear. In this study we investigated the rapid stimulatory effect of thyroxine (T(4)) on (45)Ca(2+) uptake as well as ionic currents and intracellular messengers involved in the stimulatory action of T(4) in amino acid accumulation in immature rat testes. Results indicated that 10(-9)M or 10(-6)M T(4) was able to increase immediately (45)Ca(2+) uptake after 60s of hormone exposure.
View Article and Find Full Text PDFA substantial advance in our understanding on the estrogen signaling occurred in the last decade. Estrogens interact with two receptors, ESR1 and ESR2, also known as ERalpha and ERbeta, respectively. ESR1 and ESR2 belong to the nuclear receptor family of transcription factors.
View Article and Find Full Text PDFWe have previously shown that the rat testis and vas deferens contain high levels of the relaxin receptor, RXFP1. The present study was undertaken to determine the expression of relaxin in these tissues, and the effect of exogenous relaxin on Sertoli cell proliferation and on the mRNA levels of some proteins that may contribute to epithelial secretion and tissue reorganization in the vas deferens. Relaxin mRNA levels in testis and vas deferens were much lower than in the prostate.
View Article and Find Full Text PDF1,25D3 is critical for the maintenance of normal reproduction since reduced fertility is observed in male rats on a vitamin D-deficient diet. Vitamin D-deficient male rats have incomplete spermatogenesis and degenerative testicular changes. In the present study we have examined the ionic involvement and intracellular messengers of the stimulatory effect of 1,25D3 on amino acid accumulation in immature rat testis.
View Article and Find Full Text PDFThyroid hormones (TH) play important roles in brain development. Although most of the nongenomic actions of TH are known to be calcium-dependent, the effects of 3,5,3'-triiodo-L-thyronine (T(3)) or thyroxine (T(4)) on calcium influx in cerebral cortex of rats are not clear. In this study we investigate some mechanisms involved in the effect of T(3) and T(4) on Ca(2+) uptake in slices of cerebral cortex from 10-day-old male rats.
View Article and Find Full Text PDFIn this study we describe a low-cost and reliable method for inducing fever in young male rats (28-30 days of age, 75-90 g), which seems suitable for the screening of new antipyretics. The effects of temperature measuring procedure-induced stress on the basal rectal temperature and on Baker yeast-induced hyperthermia was assessed. Rectal temperature (T) was recorded every hour for 12 h (07:00-19:00 h) with a lubricated thermistor probe.
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