Adiponectin is an adipocyte hormone involved in glucose and lipid metabolism. Recently, two receptors of this protein, called adiponectin receptor 1 (Adipo-R1) and Adipo-R2, have been cloned. The aim of this study was to examine whether adiponectin and its receptors are expressed in human and rat placentas and to evaluate the regulation of these factors by gestational age and nutritional status. Our results demonstrate that adiponectin and Adipo-R2 are localized in both human and rat placentas. Human adiponectin and Adipo-R2 are presented in cytotrophoblast and syncytiotrophoblast cells. However, rat adiponectin and Adipo-R2 change their specific cell type immunostaining during gestation. Furthermore, placental adiponectin mRNA expression is increased during pregnancy in the rat, whereas Adipo-R2 has the contrary pattern. We also assessed the effect of food restriction (30%) during gestation, and we observed that adiponectin mRNA levels decrease after 16 d of undernutrition. In contrast, placental Adipo-R2 mRNA is unchanged by undernutrition. Finally, treatment with adiponectin during gestation decreases Adipo-R2, glucose transporter 3, lipoprotein lipase, and TGF-beta mRNA expression. Taken together, our results suggest that, at least in rodents, adiponectin may be involved in the regulation of several placental functions.
Pre-slaughter stress has adverse effects on meat quality that can lead to the occurrence of Dark Firm Dry (DFD) meat in cattle. This study explores the previously uncharacterized proteome changes linked to pre-slaughter stress in the longissimus thoracis (LT) bovine muscle. Differential proteome profiles of DFD and normal (non-DFD) LT meat samples from male calves of the Rubia Gallega breed were assessed by 2-DE coupled to MS analysis (LC-MS/MS and MALDI TOF/TOF MS). A total of seven structural-contractile proteins (three different myosin light chain isoforms, two fast skeletal myosin light chain 2 isoforms, troponin C type 2 and cofilin-2) and three metabolism enzymes (triosephosphate isomerase, ATP synthase and beta-galactoside alpha-2,6-sialyltransferase) were found to have statistically significant differential abundance in sample groups. In addition, 2-DE in combination with the phosphoprotein-specific fluorescent dye Pro-Q DPS revealed that highly phosphorylated fast skeletal myosin regulatory light chain 2 isoforms underwent the most intense relative change in muscle conversion to DFD meat. Therefore, they appear to be the most sensitive biomarkers of stress just prior to slaughter in Rubia Gallega. Overall, these findings will facilitate a more integrative understanding of the biochemical processes associated with stress in cattle muscle and their effects in meat quality. Pre-slaughter stress is a crucial factor in meat production. Animals destined for slaughter are stressed by a variety of endogenous and exogenous factors that negatively affect the complex post-mortem biochemical events underlying the conversion of muscle into meat. The study of the muscle proteome has a great relevance for understanding the molecular mechanisms associated with stress. However, there is no information available on the molecular changes linked to pre-slaughter stress in cattle on the proteome scale. Our study led to the identification of a number of candidate proteins associated with the response to pre-slaughter stress in the LT bovine muscle of the Rubia Gallega breed. The functions of those significantly changed proteins have a clear biological relationship with stress response. These findings contribute to a deeper insight into the molecular pathways that respond to stress in cattle.
19 July 2012 in Journal of Molecular Endocrinology
Embryonic, adult, artificially reprogrammed, and cancer…– there are various types of cells associated with stemness. Do they have something fundamental in common? Are we applying a common name to very different entities? In this review, we will revisit the characteristics that define ‘pluripotency’, the main property of stem cells (SCs). For each main type of physiological (embryonic and adult) or synthetic (induced pluripotent) SCs, markers and functional behavior in vitro and in vivo will be described. We will review the pioneering work that has led to obtaining human SC lines, together with the problems that have arisen, both in a biological context (DNA alterations, heterogeneity, tumors, and immunogenicity) and with regard to ethical concerns. Such problems have led to proposals for new operative procedures for growing human SCs of sufficiently high quality for use as models of disease and in human therapy. Finally, we will review the data from the first clinical trials to use various types of SCs.
The Global Burden of Oral Diseases affects 3.5 billion people worldwide, representing the number of people affected by the burden of untreated dental caries, severe periodontal disease, and edentulism. Thus, much more efforts in terms of diagnostics and treatments must be provided in the fight of these outcomes. In this sense, recently, the study of saliva as biological matrix has been identified as a new landmark initiative in the search of novel and useful biomarkers to prevent and diagnose these conditions. Specifically, saliva is a rich reservoir of different proteins and peptides and accessible due to recent advances in molecular biology and specially in targeted and unbiased proteomics technologies. Nonetheless, emerging barriers are an obstacle to the study of the salivary proteome in an effective way. This review aims at giving an overall perspective of salivary biomarkers identified in several oral diseases by means of molecular biology approaches.
Diabetes is associated with a dramatic mortality rate due to its vascular complications. Chronic hyperglycemia in diabetes leads to enhanced glycation of erythrocytes and oxidative stress. Even though erythrocytes play a determining role in vascular complications, very little is known about how erythrocyte structure and functionality can be affected by glycation. Our objective was to decipher the impact of glycation on erythrocyte structure, oxidative stress parameters and capacity to interact with cultured human endothelial cells. In vitro glycated erythrocytes were prepared following incubation in the presence of different concentrations of glucose. To get insight into the in vivo relevance of our results, we compared these data to those obtained using red blood cells purified from diabetics or non-diabetics. We measured erythrocyte deformability, susceptibility to hemolysis, reactive oxygen species production and oxidative damage accumulation. Altered structures, redox status and oxidative modifications were increased in glycated erythrocytes. These modifications were associated with reduced antioxidant defence mediated by enzymatic activity. Enhanced erythrocyte phagocytosis by endothelial cells was observed when cultured with glycated erythrocytes, which was associated with increased levels of phosphatidylserine—likely as a result of an eryptosis phenomenon triggered by the hyperglycemic treatment. Most types of oxidative damage identified in in vitro glycated erythrocytes were also observed in red blood cells isolated from diabetics. These results bring new insights into the impact of glycation on erythrocyte structure, oxidative damage and their capacity to interact with endothelial cells, with a possible relevance to diabetes.