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OBJECTIVES:Dietary omega-3 fatty acids have been efficacious in decreasing serum cholesterol levels and reducing the risk of cardiovascular disease. However, the metabolic and molecular changes induced by the omega-3 fatty acid α-linolenic acid (ALA), which is found in linseed oil, are not fully understood. In this study, we showed a correlation between ALA and insulin resistance, inflammation and endoplasmic reticulum stress (ERS).METHODS:We studied 40 male mice (C57/BL6) divided into 4 groups: a control (C) group, a control + omega-3/ALA (CA) group, a high-fat diet (HFD) (H) group and a high-fat diet + omega-3/ALA (HA) group. For 8 weeks, the animals in the H and HA groups were fed a high-fat (60%) diet, while the animals in the C and CA groups received regular chow. The diets of the CA and HA groups were supplemented with 10% lyophilized ALA.RESULTS:ALA supplementation improved glucose tolerance and reduced insulin resistance, as measured by intraperitoneal glucose tolerance tests and the homeostasis model assessment for insulin resistance, respectively. In addition, ALA reduced hepatic steatosis and modified the standard fat concentration in the liver of animals fed an HFD. Dietary ALA supplementation reduced the serum levels of interleukin 6 (IL-6), interleukin 1 beta (IL-1β) and monocyte chemoattractant protein-1 (MCP-1), increased the expression of important chaperones such as binding immunoglobulin protein (BIP) and heat shock protein 70 (HSP70) and reduced the expression of C/EBP-homologous protein (CHOP) and X-box binding protein 1 (XBP1) in hepatic tissues, suggesting an ERS adaptation in response to ALA supplementation.CONCLUSIONS:Dietary ALA supplementation is effective in preventing hepatic steatosis; is associated with a reduction in insulin resistance, inflammation and ERS; and represents an alternative for improving liver function and obtaining metabolic benefits.

Dietary restriction (DR) reduces adiposity and improves metabolism in patients with one or more symptoms of metabolic syndrome. Nonetheless, it remains elusive whether the benefits of DR in humans are mediated by calorie or nutrient restriction. This study was conducted to determine whether isocaloric dietary protein restriction is sufficient to confer the beneficial effects of dietary restriction in patients with metabolic syndrome. We performed a prospective, randomized controlled dietary intervention under constant nutritional and medical supervision. Twenty-one individuals diagnosed with metabolic syndrome were randomly assigned for caloric restriction (CR; n = 11, diet of 5941 ± 686 KJ per day) or isocaloric dietary protein restriction (PR; n = 10, diet of 8409 ± 2360 KJ per day) and followed for 27 days. Like CR, PR promoted weight loss due to a reduction in adiposity, which was associated with reductions in blood glucose, lipid levels, and blood pressure. More strikingly, both CR and PR improved insulin sensitivity by 62.3% and 93.2%, respectively, after treatment. Fecal microbiome diversity was not affected by the interventions. Adipose tissue bulk RNA-Seq data revealed minor changes elicited by the interventions. After PR, terms related to leukocyte proliferation were enriched among the upregulated genes. Protein restriction is sufficient to confer almost the same clinical outcomes as calorie restriction without the need for a reduction in calorie intake. The isocaloric characteristic of the PR intervention makes this approach a more attractive and less drastic dietary strategy in clinical settings and has more significant potential to be used as adjuvant therapy for people with metabolic syndrome.

Background Bariatric surgery, especially Roux-en-Y gastric bypass (RYGB), is the most effective and durable treatment option for severe obesity. The mechanisms involving adipose tissue may be important to explain the effects of surgery. Methods We aimed to identify the genetic signatures of adipose tissue in patients undergoing RYGB. We evaluated 13 obese, non-diabetic patients (mean age 37 years, 100% women, Body mass index (BMI) 42.2 kg/m2) one day before surgery, 3 and 6 months (M) after RYGB. Results Analysis of gene expression in adipose tissue collected at surgery compared with samples collected at 3 M and 6 M Post-RYGB showed that interleukins [Interleukin 6, Tumor necrosis factor-α (TNF-α), and Monocyte chemoattractant protein-1(MCP1)] and endoplasmic reticulum stress (ERS) genes [Eukaryotic translation initiation factor 2 alpha kinase 3 (EIF2AK3) and Calreticulin (CALR)] decreased during the follow-up (P ≤ 0.01 for all). Otherwise, genes involved in energy homeostasis [Adiponectin and AMP-activated protein kinase (AMPK)], cellular response to oxidative stress [Sirtuin 1, Sirtuin 3, and Nuclear factor erythroid 2-related factor 2 (NRF2)], mitochondrial biogenesis [Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α)] and amino acids metabolism [General control nonderepressible 2 (GCN2)] increased from baseline to all other time points evaluated (P ≤ 0.01 for all). Also, expression of Peroxisome proliferator-activated receptor gamma (PPARϒ) (adipogenesis regulation) was significantly decreased after RYGB (P < 0.05). Additionally, we observed that PGC1α, SIRT1 and AMPK strongly correlated to BMI at 3 M (P ≤ 0.01 for all), as well as ADIPOQ and SIRT1 to BMI at 6 M (P ≤ 0.01 for all). Conclusions Our findings demonstrate that weight loss is associated with amelioration of inflammation and ERS and increased protection against oxidative stress in adipose tissue. These observations are strongly correlated with a decrease in BMI and essential genes that control cellular energy homeostasis, suggesting an adaptive process on a gene expression level during the caloric restriction and weight loss period after RYGB. Trial registration CAAE: 73,585,317.0.0000.5440

Night work has become necessary in our modern society. However, sleep deprivation induces a circadian misalignment that effectively contributes to the development of diseases associated with metabolic syndrome, such as obesity and diabetes. Here, we evaluated the pattern of circadian clock genes and endoplasmic reticulum stress (ERS) genes in addition to metabolic and anthropometric measures in subjects that work during a nocturnal period compared with day workers. We study 20 night workers (NW) and 20 day workers (DW) submitted to a work schedule of 12 h of work for 36 h of rest for at least 5 years in a hospital. The present report shows that NW have increased fasting blood glucose, glycated hemoglobin (HbA1c), triglycerides, and low-density lipoprotein (LDL)-cholesterol levels, and lower high-density lipoprotein (HDL)-cholesterol levels compared to DW. In addition, we observed that waist circumference (WC), waist–hip ratio (WHR), and systemic blood pressure are also increased in NW. Interestingly, gene expression analysis showed changes in CLOCK gene expression in peripheral blood mononuclear cells (PBMC) samples of NW compared to the DW, evidencing a peripheral circadian misalignment. This metabolic adaptation was accompanied by the up-regulation of many genes of ERS in NW. These findings support the hypothesis that night shift work results in disturbed glycemic and lipid control and affects the circadian cycle through the deregulation of peripheral CLOCK genes, which is possibly due to the activation of ERS. Thus, night work induces important metabolic changes that increase the risk of developing metabolic syndrome.

Several single nucleotide polymorphisms (SNPs) could indirectly, as well directly, influence metabolic parameters related to health effects in response to selenium (Se) supplementation. This study aimed to investigate whether the selenoprotein SNPs were associated with the response of Se status biomarkers to the Brazil nut consumption in patients using statins and if the variation in Se homoeostasis could affect antioxidant protection, lipid profile, muscle homoeostasis and selenoproteins mRNA. The study was performed in the Ribeirão Preto Medical School University Hospital. Thirty-two patients using statins received one unit of Brazil nut daily for 3 months. Body composition, blood Se concentrations, erythrocyte glutathione peroxidase (GPX) activity, total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triacylglycerol (TAG), creatine kinase (CK) activity and gene expression of GPX1 and selenoprotein P (SELENOP) were evaluated before and after Brazil nut consumption. The volunteers were genotyped for SNP in GPX1 (rs1050450) and SELENOP (rs3877899 and rs7579). SNPs in selenoproteins were not associated with plasma and erythrocyte Se, but SNPs in SELENOP influenced the response of erythrocyte GPX activity and CK activity, TAG and LDL after Brazil nut consumption. Also, Brazil nut consumption increased GPX1 mRNA expression only in subjects with rs1050450 CC genotype. SELENOP mRNA expression was significantly lower in subjects with rs7579 GG genotype before and after the intervention. Thus, SNP in SELENOP could be associated with interindividual differences in Se homeostasis after Brazil nut consumption, emphasising the involvement of genetic variability in response to Se consumption towards health maintenance and disease prevention.

Background Bariatric surgery, especially Roux-en-Y gastric bypass (RYGB) is the most effective and durable treatment option for population with severe obesity. The mechanisms involving adipose tissue may be important to explain the effects of surgery. Methods We aimed to identify the genetic signatures of adipose tissue in patients undergoing RYGB. We evaluated 13 obese, non-diabetic patients (mean age 37 years, 100% women, Body mass index (BMI) 42.2 kg/m2) one day before surgery, 3 and 6 months (M) after RYGB. Results Analysis of gene expression in adipose tissue collected at surgery compared with samples collected at 3M and 6M Post-RYGB showed that interleukins (Interleukin 6, Tumor necrosis factor-α (TNF-α), and Monocyte chemoattractant protein-1(MCP1)) and endoplasmic reticulum stress (ERS) genes (Eukaryotic translation initiation factor 2 alpha kinase 3 (EIF2AK3) and Calreticulin (CALR)) decreased during the follow-up (P ≤ 0.01 for all). Otherwise, genes involved in energy homeostasis (Adiponectin and AMP-activated protein kinase (AMPK)), cellular response to oxidative stress (Sirtuin 1, Sirtuin 3, and Nuclear factor erythroid 2-related factor 2 (NRF2)), mitochondrial biogenesis (Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α)) and amino acids metabolism (General control nonderepressible 2 (GCN2)) increased from baseline to all other time points evaluated (P ≤ 0.01 for all). Also, expression of Peroxisome proliferator activated receptor gamma (PPARϒ) (adipogenesis regulation) was significantly decreased after RYGB (P < 0.05) We also observed a strong positive correlation between PGC1α, SIRT1 and AMPK with BMI at 3M (P ≤ 0.01 for all) and ADIPOQ and SIRT1 with BMI at 6M (P ≤ 0.01 for all). Conclusions Our findings demonstrate that weight loss is associated with amelioration of inflammation and ERS and increased protection against oxidative stress in adipose tissue. These observations are strongly correlated with a decrease in BMI and essential genes that control cellular energy homeostasis, suggesting an adaptive process on a gene expression level during the caloric restriction and weight loss period after RYGB.

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