Optical Biosensors for the Detection of Rheumatoid Arthritis (RA) Biomarkers: A Comprehensive Review.

A comprehensive review of optical biosensors for the detection of biomarkers associated with rheumatoid arthritis (RA) is presented here, including microRNAs (miRNAs), C-reactive protein (CRP), rheumatoid factor (RF), anti-citrullinated protein antibodies (ACPA), interleukin-6 (IL-6) and histidine, which are biomarkers that enable RA detection and/or monitoring. An overview of the different optical biosensors (based on fluorescence, plasmon resonances, interferometry, surface-enhanced Raman spectroscopy (SERS) among other optical techniques) used to detect these biomarkers is given, describing their performance and main characteristics (limit of detection (LOD) and dynamic range), as well as the connection between the respective biomarker and rheumatoid arthritis. It has been observed that the relationship between the corresponding biomarker and rheumatoid arthritis tends to be obviated most of the time when explaining the mechanism of the optical biosensor, which forces the researcher to look for further information about the biomarker. This review work attempts to establish a clear association between optical sensors and rheumatoid arthritis biomarkers as well as to be an easy-to-use tool for the researchers working in this field.

Obesity and ischemic stroke modulate the methylation levels of KCNQ1 in white blood cells.

Obesity and stroke are multifactorial diseases in which genetic, epigenetic and lifestyle factors are involved. The research aims were, first, the description of genes with differential epigenetic regulation obtained by an 'omics' approach in patients with ischemic stroke and, second, to determine the importance of some regions of these selected genes in biological processes depending on the body mass index. A case-control study using two populations was designed. The first population consisted of 24 volunteers according to stroke/non-stroke and normal weight/obesity conditions. The second population included 60 stroke patients and 55 controls classified by adiposity. DNA from the first population was analyzed with a methylation microarray, showing 80 cytosine-guanine dinucleotides (CpG) sites differentially methylated in stroke and 96 CpGs in obesity, whereas 59 CpGs showed interaction. After validating these data by MassArray Epityper, the promoter region of peptidase M20 domain containing 1 (PM20D1) gene was significantly hypermethylated in stroke patients. One CpG site at Caldesmon 1 (CALD1) gene showed an interaction between stroke and obesity. Two CpGs located in the genes Wilms' tumor 1 (WT1) and potassium voltage-gated channel, KQT-like subfamily, member 1 (KCNQ1) were significantly hypermethylated in obese patients. In the second population, KCNQ1 was also hypermethylated in the obese subjects. Two CpGs of this gene were subsequently validated by methylation-sensitive high-resolution melting. Moreover, KCNQ1 methylation levels were associated with plasma KCNQ1 protein concentrations. In conclusion, obesity induced changes in the KCNQ1 methylation pattern which were also dependent on stroke. Furthermore, the epigenetic marks differentially methylated in the stroke patients were dependent on the previous obese state. These DNA methylation patterns could be used as future potential stroke biomarkers.

Novel splice-affecting variants in CYP27A1 gene in two Chilean patients with Cerebrotendinous Xanthomatosis.

Cerebrotendinous Xanthomatosis (CTX), a rare lipid storage disorder, is caused by recessive loss-of-function mutations of the 27-sterol hydroxylase (CYP27A1), producing an alteration of the synthesis of bile acids, with an accumulation of cholestanol. Clinical characteristics include juvenile cataracts, diarrhea, tendon xanthomas, cognitive impairment and other neurological manifestations. Early diagnosis is critical, because treatment with chenodeoxycholic acid may prevent neurological damage. We studied the CYP27A1 gene in two Chilean CTX patients by sequencing its nine exons, exon-intron boundaries, and cDNA from peripheral blood mononuclear cells. Patient 1 is a compound heterozygote for the novel substitution c.256-1G > T that causes exon 2 skipping, leading to a premature stop codon in exon 3, and for the previously-known pathogenic mutation c.1183C > T (p.Arg395Cys). Patient 2 is homozygous for the novel mutation c.1185-1G > A that causes exon 7 skipping and the generation of a premature stop codon in exon 8, leading to the loss of the crucial adrenoxin binding domain of CYP27A1.

Differential DNA methylation patterns between high and low responders to a weight loss intervention in overweight or obese adolescents: the EVASYON study.

In recent years, epigenetic markers emerged as a new tool to understand the influence of lifestyle factors on obesity phenotypes. Adolescence is considered an important epigenetic window over a human's lifetime. The objective of this work was to explore baseline changes in DNA methylation that could be associated with a better weight loss response after a multidisciplinary intervention program in Spanish obese or overweight adolescents. Overweight or obese adolescents (n=107) undergoing 10 wk of a multidisciplinary intervention for weight loss were assigned as high or low responders to the treatment. A methylation microarray was performed to search for baseline epigenetic differences between the 2 groups (12 subjects/group), and MALDI-TOF mass spectrometry was used to validate (n=107) relevant CpG sites and surrounding regions. After validation, 5 regions located in or near AQP9, DUSP22, HIPK3, TNNT1, and TNNI3 genes showed differential methylation levels between high and low responders to the multidisciplinary weight loss intervention. Moreover, a calculated methylation score was significantly associated with changes in weight, BMI-SDS, and body fat mass loss after the treatment. In summary, we have identified 5 DNA regions that are differentially methylated depending on weight loss response. These methylation changes may help to better understand the weight loss response in obese adolescents.

Transcriptomic and epigenetic changes in early liver steatosis associated to obesity: effect of dietary methyl donor supplementation.

Non-alcoholic fatty liver disease is a primary hepatic manifestation of obesity and an important adverse metabolic syndrome trait. Animal models of diet-induced obesity promote liver fat accumulation putatively associated with alterations in epigenetic profile. Dietary methyl donor-supplementation may protect against this disturbance during early developmental stages affecting the molecular basis of gene regulation. The aim of this study was to investigate the transcriptomic and epigenetic mechanisms implicated in liver fat accumulation as a result of an obesogenic diet and the putative preventive role of dietary methyl donors. Forty-eight male Wistar rats were assigned into four dietary groups for 8 weeks; control, control methyl-donor-supplemented with a dietary cocktail containing betaine, choline, vitamin B12 and folic acid, high-fat-sucrose and high-fat-sucrose methyl-donor-supplemented. Liver fat accumulation induced by a HFS diet was prevented by methyl donor supplementation in HFS-fed animals. A liver mRNA microarray, subsequently validated by real time-qPCR, showed modifications in some biologically relevant genes involved in obesity development and lipid metabolism (Lepr, Srebf2, Agpat3 and Esr1). Liver global DNA methylation was decreased by methyl donor supplementation in control-fed animals. Methylation levels of specific CpG sites from Srebf2, Agpat3 and Esr1 promoter regions showed changes due to the obesogenic diet and the supplementation with methyl donors. Interestingly, Srebf2 CpG23_24 methylation levels (-167 bp and -156 bp with respect to the transcriptional start site) correlated with HDLc plasma levels, whereas Esr1 CpG14 (-2623 bp) methylation levels were associated with body and liver weights and fat content. Furthermore HFS diet-induced liver fat accumulation was prevented by methyl donor supplementation. In conclusion, both obesogenic diet and methyl donor supplementation modified the mRNA hepatic profile as well as the methylation of specific gene promoters and total DNA.

Maternal methyl donors supplementation during lactation prevents the hyperhomocysteinemia induced by a high-fat-sucrose intake by dams.

Maternal perinatal nutrition may program offspring metabolic features. Epigenetic regulation is one of the candidate mechanisms that may be affected by maternal dietary methyl donors intake as potential controllers of plasma homocysteine levels. Thirty-two Wistar pregnant rats were randomly assigned into four dietary groups during lactation: control, control supplemented with methyl donors, high-fat-sucrose and high-fat-sucrose supplemented with methyl donors. Physiological outcomes in the offspring were measured, including hepatic mRNA expression and global DNA methylation after weaning. The newborns whose mothers were fed the obesogenic diet were heavier longer and with a higher adiposity and intrahepatic fat content. Interestingly, increased levels of plasma homocysteine induced by the maternal high-fat-sucrose dietary intake were prevented in both sexes by maternal methyl donors supplementation. Total hepatic DNA methylation decreased in females due to maternal methyl donors administration, while Dnmt3a hepatic mRNA levels decreased accompanying the high-fat-sucrose consumption. Furthermore, a negative association between Dnmt3a liver mRNA levels and plasma homocysteine concentrations was found. Maternal high-fat-sucrose diet during lactation could program offspring obesity features, while methyl donors supplementation prevented the onset of high hyperhomocysteinemia. Maternal dietary intake also affected hepatic DNA methylation metabolism, which could be linked with the regulation of the methionine-homocysteine cycle.

Screening of polyphenolic plant extracts for anti-obesity properties in Wistar rats.

BACKGROUND: Polyphenols have been reported to prevent chronic diseases such as cardiovascular diseases, cancers, diabetes and neurodegenerative diseases. The objective of the study was to conduct a screening for potential anti-obesity polyphenolic plant extracts using a diet-induced animal model. Rats were fed a high-fat-sucrose (HFS) diet with or without supplementation of different polyphenolic plant extracts (almond, apple, cinnamon, orange blossom, hamamelis, lime blossom, grape vine, and birch) for 56-64 days. RESULTS: Body weight gain was lower in rats supplemented with apple, cinnamon, hamamelis and birch extracts as compared to HFS non-supplemented group. Moreover, apple and cinnamon extracts prevented the increase in fat mass promoted by the HFS diet. Insulin resistance, estimated by the homostatic model assessment-insulin resistance (HOMA-IR) index, was reduced in rats fed apple, cinnamon, hamamelis and birch extracts. Apple extract also prevented the HFS-induced hyperglycaemia and hyperleptinaemia. CONCLUSION: Only apple and cinnamon extracts were finally considered as potentially important anti-obesogenic extracts, due to their body fat-lowering effects, while the improvement of obesity-related metabolic complications by apple polyphenols highlights this extract as a promising functional food ingredient for the management of obesity and its metabolic complications.

Adiposoft: automated software for the analysis of white adipose tissue cellularity in histological sections.

The accurate estimation of the number and size of cells provides relevant information on the kinetics of growth and the physiological status of a given tissue or organ. Here, we present Adiposoft, a fully automated open-source software for the analysis of white adipose tissue cellularity in histological sections. First, we describe the sequence of image analysis routines implemented by the program. Then, we evaluate our software by comparing it with other adipose tissue quantification methods, namely, with the manual analysis of cells in histological sections (used as gold standard) and with the automated analysis of cells in suspension, the most commonly used method. Our results show significant concordance between Adiposoft and the other two methods. We also demonstrate the ability of the proposed method to distinguish the cellular composition of three different rat fat depots. Moreover, we found high correlation and low disagreement between Adiposoft and the manual delineation of cells. We conclude that Adiposoft provides accurate results while considerably reducing the amount of time and effort required for the analysis.

A dual epigenomic approach for the search of obesity biomarkers: DNA methylation in relation to diet-induced weight loss.

Epigenetics could help to explain individual differences in weight loss after an energy-restriction intervention. Here, we identify novel potential epigenetic biomarkers of weight loss, comparing DNA methylation patterns of high and low responders to a hypocaloric diet. Twenty-five overweight or obese men participated in an 8-wk caloric restriction intervention. DNA was isolated from peripheral blood mononuclear cells and treated with bisulfite. The basal and endpoint epigenetic differences between high and low responders were analyzed by methylation microarray, which was also useful in comparing epigenetic changes due to the nutrition intervention. Subsequently, MALDI-TOF mass spectrometry was used to validate several relevant CpGs and the surrounding regions. DNA methylation levels in several CpGs located in the ATP10A and CD44 genes showed statistical baseline differences depending on the weight-loss outcome. At the treatment endpoint, DNA methylation levels of several CpGs on the WT1 promoter were statistically more methylated in the high than in the low responders. Finally, different CpG sites from WT1 and ATP10A were significantly modified as a result of the intervention. In summary, hypocaloric-diet-induced weight loss in humans could alter DNA methylation status of specific genes. Moreover, baseline DNA methylation patterns may be used as epigenetic markers that could help to predict weight loss.

The rs7204609 polymorphism in the fat mass and obesity-associated gene is positively associated with central obesity and microalbuminuria in patients with type 2 diabetes from Southern Brazil.

OBJECTIVE: Single nucleotide polymorphisms (SNPs) in the fat mass and obesity-associated (FTO) gene, especially the common rs9939609 (A/T) SNP, are associated with body mass index (BMI), diabetes, and metabolic syndrome (MetS). MetS is highly prevalent in patients with type 2 diabetes and has been associated with chronic diabetic complications. Therefore, the aim of this study was to evaluate possible associations of the scarcely investigated rs7204609 (C/T) polymorphism, as well as the rs9939609 (A/T) polymorphism, with MetS and chronic diabetic complications in type 2 diabetic patients from Southern Brazil. DESIGN: This was a cross-sectional study. PATIENTS AND METHODS: A total of 236 patients with type 2 diabetes (age: 60.0 ± 10.3 years; diabetes duration: 12.7 ± 8.2 years; 53.4% women) were genotyped for the FTO rs7204609 and rs9939609 polymorphisms (ABI PRISM 7000 Real-Time PCR System). Patients underwent clinical, laboratory, and nutritional evaluation. MetS was defined according to the 2009-Joint Interim Statement. RESULTS: Carriers of C allele of the rs7204609 polymorphism (CT/CC genotypes, n = 35) were at increased risk for the presence of MetS (odds ratio [OR] = 4.56; 95% CI: 1.04 to 19.9), elevated waist circumference (OR = 8.66; 95% CI: 1.12 to 66.7), BMI: ≥ 30 kg/m(2) (OR = 3.71; 95% CI: 1.71 to 8.02), and microalbuminuria (OR = 2.30; 95% CI: 1.08 to 4.88), adjusted for gender and diabetes duration (P < .05 for all models). The rs9939609 polymorphism was not associated with MetS, elevated waist circumference or BMI, or diabetic complications. Daily energy and nutrient intakes did not differ according to the presence of the polymorphisms. CONCLUSIONS: The C allele of the rs7204609 polymorphism in the FTO gene increased the chance for the presence of MetS, especially central obesity, and microalbuminuria, independently of energy and nutrient intakes in this sample of type 2 diabetic patients from Southern Brazil.

Selenoprotein-P is down-regulated in prostate cancer, which results in lack of protection against oxidative damage.

BACKGROUND: Oxidative stress plays a role in prostate cancer (PrCa) initiation and development. Selenoprotein-P (SepP; a protein involved in antioxidant defence) mRNA levels are down-regulated in PrCa. The main goal of our study was to assess whether SepP protects prostate cells from reactive oxygen species (ROS) in prostate carcinogenesis. METHODS: Modification of SepP levels and ROS conditions in C3(1)/Tag-derived cell lines representing prostate epithelial neoplasia (PIN) lesions (Pr-111, with high SepP expression); and invasive tumors (Pr-14, with very low SepP expression). RESULTS: Both Pr-111 and Pr-14 cells express ApoER2 (SepP receptor), which suggests that they may uptake SepP. Pr-14 cells had much higher ROS levels than Pr-111 cells and were highly sensitive to H(2)O(2)-mediated cytotoxicity. When SepP mRNA levels were knocked down with siRNAs in Pr-111 cells, a significant increase in ROS and cell growth inhibition upon H(2)O(2) exposure was found. Subsequent administration of purified SepP in the culture medium of these cells was able to rescue the original phenotype. Similarly, administration of SepP to Pr-14 cells was able to reduce ROS concentrations. Administration of flutamide decreased SepP mRNA levels whereas dihydrotestosterone or synthetic androgens induced SepP expression, indicating the importance of androgens for SepP expression. Immunohistochemical analysis using a PrCa tissue microarray further revealed that SepP protein was reduced in 60.8% prostate tumors compared to benign prostates. CONCLUSIONS: Levels of SepP in prostate cells determine basal ROS levels and sensitivity to H(2)O(2)-induced cytotoxicity. Deregulation of SepP during prostate carcinogenesis may increase free radicals, thus promoting tumor development and de-differentiation.

High-fat diet feeding alters metabolic response to fasting/non fasting conditions. Effect on caveolin expression and insulin signalling.

BACKGROUND: The effect of food intake on caveolin expression in relation to insulin signalling was studied in skeletal muscle and adipocytes from retroperitoneal (RP) and subcutaneous (SC) adipose tissue, comparing fasted (F) to not fasted (NF) rats that had been fed a control or high-fat (HF) diet for 72 days. METHODS: Serum glucose was analysed enzymatically and insulin and leptin by ELISA. Caveolins and insulin signalling intermediaries (IR, IRS-1 and 2 and GLUT4) were determined by RT-PCR and western blotting. Caveolin and IR phosphorylation was measured by immunoprecipitation. Data were analysed with Mann-Whitney U test. RESULTS: High-fat fed animals showed metabolic alterations and developed obesity and insulin resistance. In skeletal muscle, food intake (NF) induced activation of IR and increased expression of IRS-2 in control animals with normal metabolic response. HF animals became overweight, hyperglycaemic, hyperinsulinemic, hyperleptinemic and showed insulin resistance. In skeletal muscle of these animals, food intake (NF) also induced IRS-2 expression together with IR, although this was not active. Caveolin 3 expression in this tissue was increased by food intake (NF) in animals fed either diet. In RP adipocytes of control animals, food intake (NF) decreased IR and IRS-2 expression but increased that of GLUT4. A similar but less intense response was found in SC adipocytes. Food intake (NF) did not change caveolin expression in RP adipocytes with either diet, but in SC adipocytes of HF animals a reduction was observed. Food intake (NF) decreased caveolin-1 phosphorylation in RP but increased it in SC adipocytes of control animals, whereas it increased caveolin-2 phosphorylation in both types of adipocytes independently of the diet. CONCLUSIONS: Animals fed a control-diet show a normal response to food intake (NF), with activation of the insulin signalling pathway but without appreciable changes in caveolin expression, except a small increase of caveolin-3 in muscle. Animals fed a high-fat diet develop metabolic changes that result in insulin signalling impairment. In these animals, caveolin expression in muscle and adipocytes seems to be regulated independently of insulin signalling.

Natural inhibitors of pancreatic lipase as new players in obesity treatment.

Obesity is a multifactorial disease characterized by an excessive weight for height due to an enlarged fat deposition such as adipose tissue, which is attributed to a higher calorie intake than the energy expenditure. The key strategy to combat obesity is to prevent chronic positive impairments in the energy equation. However, it is often difficult to maintain energy balance, because many available foods are high-energy yielding, which is usually accompanied by low levels of physical activity. The pharmaceutical industry has invested many efforts in producing antiobesity drugs; but only a lipid digestion inhibitor obtained from an actinobacterium is currently approved and authorized in Europe for obesity treatment. This compound inhibits the activity of pancreatic lipase, which is one of the enzymes involved in fat digestion. In a similar way, hundreds of extracts are currently being isolated from plants, fungi, algae, or bacteria and screened for their potential inhibition of pancreatic lipase activity. Among them, extracts isolated from common foodstuffs such as tea, soybean, ginseng, yerba mate, peanut, apple, or grapevine have been reported. Some of them are polyphenols and saponins with an inhibitory effect on pancreatic lipase activity, which could be applied in the management of the obesity epidemic.

Caveolin expression and activation in retroperitoneal and subcutaneous adipocytes: influence of a high-fat diet.

The effect of a high-fat diet on the expression of the three main isoforms of caveolins in adipocytes isolated from rat retroperitoneal and subcutaneous white adipose tissue was investigated. Two distinct phases can be distinguished on a time-dependent response in adipocytes from both locations. The early stage affects only to retroperitoneal adipocytes and implies caveolin-1 activation and caveolin-2 inactivation, together with increased expression of insulin signaling intermediaries. This initial response would be aimed to counterbalance the energy overload. Continued exposure to the high-fat diet produces an increase in circulating glucose and insulin levels, inducing a late stage in which adipocytes from both locations are affected. This late stage is characterized by general increased caveolin-1 and caveolin-2 expression; while on the other hand, the insulin signaling intermediaries are downregulated, with the noticeable exception of GLUT-4, whose expression remains high. Therefore, it seems that at this stage caveolins and GLUT-4 are regulated independently of the insulin pathway, through a mechanism that could be mediated by inflammation and oxidative stress associated with obesity. Although this GLUT-4 upregulation suggests a response against the raise in circulating glucose, this might not be the case, since the developing insulin resistance at this stage indicates a prediabetic state. We have also found that the high-fat diet is able to induce the expression of muscle-specific caveolin-3 in retroperitoneal adipocytes since the initial phase. This observation is similar to what we reported previously in skeletal muscle (Gómez-Ruiz et al., 2009, FEBS Lett 583:3259-3264), suggesting a similar regulatory mechanism for this isoform.

Weight gain induced by an isocaloric pair-fed high fat diet: a nutriepigenetic study on FASN and NDUFB6 gene promoters.

Experimental studies have demonstrated that dietary macronutrient distribution plays an important role in insulin regulation, a risk factor associated to obesity, diabetes and other metabolic disorders. To assess whether the macronutrient composition of the diet could be related to obesity onset by affecting the epigenetic regulation of gene expression, we investigated in rats the metabolic effects of two pair-fed isocaloric diets: control (rich in carbohydrates) and high fat diet (rich in fat; HFD). Compared to controls, HFD induced higher weight gain and adiposity and impaired glucose tolerance, which was accompanied by a slight increase in adiponectin levels and liver steatosis. Epididymal adipose tissue expression of the fatty acid synthase (FASN) gene and NADH dehydrogenase (ubiquinone) 1ß-subcomplex 6 (NDUFB6) were significantly reduced in HFD group. These variations in mRNA levels were accompanied by changes in the methylation patterns of several CpG islands located in the promoter region of these genes. However, no correlations were found between gene expression and the methylation status. These results suggest that high fat intake produces overweighted rats independently of total energy intake. These diets could also induce some epigenetic changes in the promoters of key genes that could influence gene expression and may be behind metabolic alterations.

Obesity induced by a pair-fed high fat sucrose diet: methylation and expression pattern of genes related to energy homeostasis.

BACKGROUND: The expression of some genes controlling energy homeostasis could be regulated by epigenetic mechanisms that may play a role in body weight regulation. Thus, it is known that various nutritional factors affect DNA methylation. In order to assess whether the macronutrient composition of the diet could be related to the epigenetic regulation of gene expression and with obesity development, we investigated the effects on methylation and expression patterns of two pair-fed isocaloric diets in rats: control (rich in starch) and HFS (rich in fat and sucrose). RESULTS: The pair-fed HFS diet induced higher weight gain and adiposity as compared to the controls as well as liver triglyceride accumulation and oxidative stress. Feeding the HFS diet impaired glucose tolerance and serum triglycerides and cholesterol. Liver glucokinase expression, a key glycolytic gene, remained unaltered, as well as the mRNA values of fatty acid synthase and NADH dehydrogenase (ubiquinone) 1 beta subcomplex, 6 (NDUFB6) in liver and visceral adipocytes, which regulate lipogenesis and mitochondrial oxidative metabolism, respectively. Liver expression of hydroxyacyl-coenzyme A dehydrogenase (HADHB), a key gene of beta-oxidation pathway, was higher in the HFS-fed animals. However, the methylation status of CpG islands in HADHB and glucokinase genes remained unchanged after feeding the HFS diet. CONCLUSIONS: These results confirm that the distribution and type of macronutrients (starch vs. sucrose, and percent of fat) influence obesity onset and the associated metabolic complications. HFS diets produce obesity independently of total energy intake, although apparently no epigenetic (DNA methylation) changes accompanied the modifications observed in gene expression.

Some cyclin-dependent kinase inhibitors-related genes are regulated by vitamin C in a model of diet-induced obesity.

The aim of this research was to investigate differential gene expression of cyclin-dependent kinase inhibitors (CKIs) in white adipose tissue (WAT) and liver from high-fat fed male Wistar rats with or without vitamin C (VC) supplementation (750 mg/kg of body weight). After 56 d of experimentation, animals fed on a cafeteria diet increased significantly body weights and total body fat. Reverse transcription-polymerase chain reaction (RT-PCR) studies showed that cafeteria diet decreased p21 and p57 mRNA expression in subcutaneous WAT and increased p21 mRNA in liver. Overall, these data provide new information about the role of high fat intake on mRNA levels of several CKIs with implications in adipogenesis, cell metabolism and weight homeostasis. Interestingly, VC supplementation partially prevented diet-induced adiposity and increased p27 mRNA in liver without any changes in the other tissues and genes analyzed. Thus, hepatic mRNA changes induced by ascorbic acid indicate a possible role of these genes in diet-induced oxidative stress processes.

11-Beta hydroxysteroid dehydrogenase type 2 expression in white adipose tissue is strongly correlated with adiposity.

Glucocorticoid action within the cells is regulated by the levels of glucocorticoid receptor (GR) expression and two enzymes, 11-beta hydroxysteroid dehydrogenase type 1 (11betaHSD1), which converts inactive to active glucocorticoids, and 11-beta hydroxysteroid dehydrogenase type 2 (11betaHSD2), which regulates the access of active glucocorticoids to the receptor by converting cortisol/corticosterone to the glucocorticoid-inactive form cortisone/dehydrocorticosterone. Male Wistar rats developed obesity by being fed a high-fat diet for 56 days, and GR, 11betaHSD1 and 11betaHSD2 gene expression were compared with control-diet fed animals. Gene expression analysis of 11betaHSD1, 11betaHSD2 and GR were performed by RT-PCR in subcutaneous and retroperitoneal adipose tissue. High-fat fed animals overexpressed 11betaHSD2 in subcutaneous but not in retroperitoneal fat. Interestingly, mRNA levels strongly correlated in both tissues with different parameters related to obesity, such as body weight, adiposity and insulin resistance, suggesting that this gene is a reliable marker of adiposity in this rat model of obesity. Thus, 11betaHSD2 is expressed in adipose tissue by both adipocytes and stromal-vascular cells, which suggests that this enzyme may play an important role in preventing fat accumulation in adipose tissue.

Effects of perinatal diet and prenatal stress on the behavioural profile of aged male and female rats.

The present work studies whether chronic prenatal stress (PS) influences the long-term sex-dependent neuropsychological status of offspring and the effects of an early dietary intervention in the dam. In addition, dams were fed with either a high-fat sugar diet (HFSD) or methyl donor supplemented diet (MDSD). PS procedure did not affect body weight of the offspring. MDSD induced decreases in body weight both in male and female offspring (1 month) that were still present in aged rats. HFSD induced an increase in body weight both in male and female offspring that did not persist in aged rats. In the Porsolt forced swimming test, only young males showed increases in immobility time that were reversed by MDSD. In old female rats (20 months), PS-induced cognitive impairment in both the novel object recognition test (NORT) and in the Morris water maze that was reversed by MDSD, whereas in old males, cognitive impairments and reversion by MDSD was evident only in the Morris water maze. HFSD induced cognitive impairment in both control and PS old rats, but there was no additive effect of PS and HFSD. It is proposed here that the diversity of symptoms following PS could arise from programming effects in early brain development and that these effects could be modified by dietary intake of the dam.