Differences in metabolic biomarkers in the blood and gene expression profiles of peripheral blood mononuclear cells among normal weight, mildly obese and moderately obese subjects

CPEB2-activated Prdm16 translation promotes brown adipocyte function and prevents obesity

OBJECTIVE

Brown adipose tissue (BAT) plays an important role in mammalian thermogenesis through the expression of uncoupling protein 1 (UCP1). Our previous study identified cytoplasmic polyadenylation element binding protein 2 (CPEB2) as a key regulator that activates the translation of Ucp1 with a long 3'-untranslated region (Ucp1L) in response to adrenergic signaling. Mice lacking CPEB2 or Ucp1L exhibited reduced UCP1 expression and impaired thermogenesis; however, only CPEB2-null mice displayed obesogenic phenotypes. Hence, this study aims to investigate how CPEB2-controlled translation impacts body weight.

METHODS

Body weight measurements were conducted on mice with global knockout (KO) of CPEB2, UCP1 or Ucp1L, as well as those with conditional knockout of CPEB2 in neurons or adipose tissues. RNA sequencing coupled with bioinformatics analysis was used to identify dysregulated gene expression in CPEB2-deficient BAT. The role of CPEB2 in regulating PRD1-BF1-RIZ1 homologous-domain containing 16 (PRDM16) expression was subsequently confirmed by RT-qPCR, Western blotting, polysomal profiling and luciferase reporter assays. Adeno-associated viruses (AAV) expressing CPEB2 or PRDM16 were delivered into BAT to assess their efficacy in mitigating weight gain in CPEB2-KO mice.

RESULTS

We validated that defective BAT function contributed to the increased weight gain in CPEB2-KO mice. Transcriptomic profiling revealed upregulated expression of genes associated with muscle development in CPEB2-KO BAT. Given that both brown adipocytes and myocytes stem from myogenic factor 5-expressing precursors, with their cell-fate differentiation regulated by PRDM16, we identified that Prdm16 was translationally upregulated by CPEB2. Ectopic expression of PRDM16 in CPEB2-deprived BAT restored gene expression profiles and decreased weight gain in CPEB2-KO mice.

CONCLUSIONS

In addition to Ucp1L, activation of Prdm16 translation by CPEB2 is critical for sustaining brown adipocyte function. These findings unveil a new layer of post-transcriptional regulation governed by CPEB2, fine-tuning thermogenic and metabolic activities of brown adipocytes to control body weight.

SIRT1 and FOXO1 role on MASLD risk: effects of DHA-rich n-3 PUFA supplementation and exercise in aged obese female mice and in post-menopausal overweight/obese women

Sirtuins 1 (SIRT1) and Forkhead box protein O1 (FOXO1) expression have been associated with obesity and metabolic dysfunction-associated steatotic liver disease (MASLD). Exercise and/or docosahexaenoic acid (DHA) supplementation have shown beneficial effects on MASLD. The current study aims to assess the relationships between Sirt1, Foxo1 mRNA levels and several MASLD biomarkers, as well as the effects of DHA-rich n-3 PUFA supplementation and/or exercise in the steatotic liver of aged obese female mice, and in peripheral blood mononuclear cells (PBMCs) of postmenopausal women with overweight/obesity. In the liver of 18-month-old mice, Sirt1 levels positively correlated with the expression of genes related to fatty acid oxidation, and negatively correlated with lipogenic and proinflammatory genes. Exercise (long-term treadmill training), especially when combined with DHA, upregulated hepatic Sirt1 mRNA levels. Liver Foxo1 mRNA levels positively associated with hepatic triglycerides (TG) content and the expression of lipogenic and pro-inflammatory genes, while negatively correlated with the lipolytic gene Hsl. In PBMCs of postmenopausal women with overweight/obesity, FOXO1 mRNA expression negatively correlated with the hepatic steatosis index (HSI) and the Zhejiang University index (ZJU). After 16-weeks of DHA-rich PUFA supplementation and/or progressive resistance training (RT), most groups exhibited reduced MASLD biomarkers and risk indexes accompanying with body fat mass reduction, but no significant changes were found between the intervention groups. However, in PBMCs n-3 supplementation upregulated FOXO1 expression, and the RT groups exhibited higher SIRT1 expression. In summary, SIRT1 and FOXO1 could be involved in the beneficial mechanisms of exercise and n-3 PUFA supplementation related to MASLD manifestation.

The Expression of Genes Related to Reverse Cholesterol Transport and Leptin Receptor Pathways in Peripheral Blood Mononuclear Cells Are Decreased in Morbid Obesity and Related to Liver Function

Obesity is frequently accompanied by non-alcoholic fatty liver disease (NAFLD). These two diseases are associated with altered lipid metabolism, in which reverse cholesterol transport (LXRα/ABCA1/ABCG1) and leptin response (leptin receptor (Ob-Rb)/Sam68) are involved. The two pathways were evaluated in peripheral blood mononuclear cells (PBMCs) from 86 patients with morbid obesity (MO) before and six months after Roux-en-Y gastric bypass (RYGB) and 38 non-obese subjects. In the LXRα pathway, LXRα, ABCA1, and ABCG1 mRNA expressions were decreased in MO compared to non-obese subjects (p < 0.001, respectively). Ob-Rb was decreased (p < 0.001), whereas Sam68 was increased (p < 0.001) in MO. RYGB did not change mRNA gene expressions. In the MO group, the LXRα pathway (LXRα/ABCA1/ABCG1) negatively correlated with obesity-related variables (weight, body mass index, and hip), inflammation (C-reactive protein), and liver function (alanine-aminotransferase, alkaline phosphatase, and fatty liver index), and positively with serum albumin. In the Ob-R pathway, Ob-Rb and Sam68 negatively correlated with alanine-aminotransferase and positively with albumin. The alteration of LXRα and Ob-R pathways may play an important role in NAFLD development in MO. It is possible that MO patients may require more than 6 months following RYBGB to normalize gene expression related to reverse cholesterol transport or leptin responsiveness.

An integrative pan-cancer analysis of the molecular characteristics of dietary restriction in tumour microenvironment

BACKGROUND

Dietary restriction (DR), a general term for dieting, has been demonstrated as an effective intervention in reducing the occurrence of cancers. Molecular activities associated with DR are crucial in mediating its anti-cancer effects, yet a comprehensive exploration of the landscape of these activities at the pan-cancer level is still lacking.

METHODS

We proposed a computational approach for quantifying DR-related molecular activities and delineating the landscape of these activities across 33 cancer types and 30 normal tissues within 27,320 samples. We thoroughly examined the associations between DR-related molecular activities and various factors, including the tumour microenvironment, immunological phenotypes, genomic features, and clinical prognosis. Meanwhile, we identified two DR genes that show potential as prognostic predictors in hepatocellular carcinoma and verified them by immunohistochemical assays in 90 patients.

FINDINGS

We found that DR-related molecular activities showed a close association with tumour immunity and hold potential for predicting immunotherapy responses in various cancers. Importantly, a higher level of DR-related molecular activities is associated with improved overall survival and cancer-specific survival. FZD1 and G6PD are two DR genes that serve as biomarkers for predicting the prognosis of patients with hepatocellular carcinoma.

INTERPRETATION

This study presents a robust link between DR-related molecular activities and tumour immunity across multiple cancer types. Our research could open the path for further investigation of DR-related molecular processes in cancer treatment.

FUNDING

National Natural Science Foundation of China (Grant No. 82000628) and the Guangdong-Hong Kong-Macao University Joint Laboratory of Interventional Medicine Foundation of Guangdong Province (Grant No. 2023LSYS001).

Leptin receptor expression in blood mononuclear cells of lactating women is associated with infant body weight: Potential role as a molecular biomarker

BACKGROUND

Molecular biomarkers of maternal leptin resistance associated with infant weight are needed.

OBJECTIVES

To evaluate gene expression of leptin receptor (LEPR), suppressor of cytokine signalling 3 (SOCS3) and insulin receptor in peripheral blood mononuclear cells (PBMCs) of lactating women and their relationship with infant body weight and adiposity.

METHODS

At day 10 postpartum, maternal gene expression in PBMCs as well as leptin and insulin concentrations in plasma and milk were assessed (n = 68). Infant weight and BMI z-scores, skinfolds and arm circumference were obtained at 10 days and/or at 3 months old.

RESULTS

In mothers with pre-pregnancy overweight or obesity (OW/OB), LEPR expression was reduced (p = 0.013) whereas plasma and milk leptin and milk insulin concentrations were elevated. LEPR expression was positively related with infant weight z-score (Beta (95% CI): 0.40 (0.17, 0.63), p = 0.001) but not with leptin concentrations. SOCS3 expression was positively related with infant weight z-score (Beta (95% CI): 0.28 (0.04, 0.51), p = 0.024) and arm circumference (Beta (95% CI): 0.57 (0.32, 0.82), p < 0.001). Relationships remained significant after adjusting for maternal and infant confounders.

CONCLUSIONS

LEPR and SOCS3 gene expression in PBMCs are novel maternal molecular biomarkers that reflect leptin resistance and are associated with infant body weight and adiposity.

Associations of gene expression in blood with BMI and weight changes among women in the Norwegian Women and Cancer postgenome cohort

OBJECTIVE

This study aimed to evaluate associations between blood gene expression profiles and (1) current BMI and (2) past weight changes (WCs) among women who had never been diagnosed with cancer in the Norwegian Women and Cancer (NOWAC) postgenome cohort.

METHODS

This cross-sectional study (N = 1694) used gene expression profiles and information from three questionnaires: Q1 (baseline), Q2 (follow-up), and Q3 (blood collection). The authors performed gene-wise linear regression models to identify differentially expressed genes (DEGs) and functional enrichment analyses to identify their biological functions.

RESULTS

When assessing BMIQ3 , the study observed 2394, 769, and 768 DEGs for the obesity-versus-normal weight, obesity-versus-overweight, and overweight-versus-normal weight comparisons, respectively. Up to 169 DEGs were observed when investigating WCQ3-Q1 (mean = 7 years, range = 5.5-14 years) and WCQ3-Q2 (mean = 1 year, range = <1 month-9 years) in interaction models with BMI categories, of which 1 to 169 genes were associated with WCs and 0 to 9 were associated with interaction effects of BMI and WCs. Biological functions of BMI-associated DEGs were linked to metabolism, erythrocytes, oxidative stress, and immune processes, whereas WC-associated DEGs were linked to signal transduction.

CONCLUSIONS

Many BMI-associated but few WC-associated DEGs were identified in the blood of women in Norway. The biological functions of BMI-associated DEGs likely reflect systemic impacts of obesity, especially blood reticulocyte-erythrocyte ratio shifts.

Mitochondrial reprogramming in peripheral blood mononuclear cells of patients with glycogen storage disease type Ia

BACKGROUND

Glycogen storage disease type Ia (GSDIa) is an inborn metabolic disorder caused by the deficiency of glucose-6-phospatase-α (G6Pase-α) leading to mitochondrial dysfunction. It remains unclear whether mitochondrial dysfunction is present in patients' peripheral blood mononuclear cells (PBMC) and whether dietary treatment can play a role. The aim of this study was to investigate mitochondrial function in PBMC of GSDIa patients.

METHODS

Ten GSDIa patients and 10 age-, sex- and fasting-time matched controls were enrolled. Expression of genes involved in mitochondrial function and activity of key fatty acid oxidation (FAO) and Krebs cycle proteins were assessed in PBMC. Targeted metabolomics and assessment of metabolic control markers were also performed.

RESULTS

Adult GSDIa patients showed increased CPT1A, SDHB, TFAM, mTOR expression (p < 0.05) and increased VLCAD, CPT2 and citrate synthase activity in PBMC (p < 0.05). VLCAD activity directly correlated with WC (p < 0.01), BMI (p < 0.05), serum malonycarnitine levels (p < 0.05). CPT2 activity directly correlated with BMI (p < 0.05).

CONCLUSION

Mitochondrial reprogramming is detectable in PBMC of GSDIa patients. This feature may develop as an adaptation to the liver enzyme defect and may be triggered by dietary (over)treatment in the frame of G6Pase-α deficiency. PBMC can represent an adequate mean to assess (diet-induced) metabolic disturbances in GSDIa.

Enhanced mitochondrial oxidative metabolism in peripheral blood mononuclear cells is associated with fatty liver in obese young adults

Systemic inflammation underlies the association between obesity and nonalcoholic fatty liver disease (NAFLD). Here, we investigated functional changes in leukocytes' mitochondria in obese individuals and their associations with NAFLD. We analyzed 14 obese male Japanese university students whose body mass index was > 30 kg/m2 and 15 healthy age- and sex-matched lean university students as controls. We observed that the mitochondrial oxidative phosphorylation (OXPHOS) capacity with complex I + II-linked substrates in peripheral blood mononuclear cells (PBMCs), which was measured using a high-resolution respirometry, was significantly higher in the obese group versus the controls. The PBMCs' mitochondrial complex IV capacity was also higher in the obese subjects. All of the obese subjects had hepatic steatosis defined by a fatty liver index (FLI) score ≥ 60, and there was a positive correlation between their FLI scores and their PBMCs' mitochondrial OXPHOS capacity. The increased PBMCs' mitochondrial OXPHOS capacity was associated with insulin resistance, systemic inflammation, and higher serum levels of interleukin-6 in the entire series of subjects. Our results suggest that the mitochondrial respiratory capacity is increased in the PBMCs at the early stage of obesity, and the enhanced PBMCs' mitochondrial oxidative metabolism is associated with hepatic steatosis in obese young adults.

Whole-Genome Transcriptomics of PBMC to Identify Biomarkers of Early Metabolic Risk in Apparently Healthy People with Overweight-Obesity and in Normal-Weight Subjects

SCOPE

Peripheral blood mononuclear cells (PBMC) provide a useful and minimally invasive source of biomarkers. Here to identify PBMC transcriptomic biomarkers predictive of metabolic impairment related to increased adiposity is aimed.

METHODS AND RESULTS

The study analyzed the global PBMC transcriptome in metabolically healthy (normoglycemic) volunteers with overweight-obesity (OW-OB, n = 12), and in subjects with metabolically obese normal-weight (MONW, n = 5) phenotype, in comparison to normal-weight (NW, n = 12) controls. The study identifies 1072 differentially expressed genes (DEGs) in OW-OB versus NW and 992 in MONW versus NW. Hierarchical clustering of the top 100 DEGs clearly distinguishes OW-OB and MONW from NW. Remarkably, the OW-OB and MONW phenotypes share 257 DEGs regulated in the same direction. The top up-regulated gene CXCL8, coding for interleukin 8, with a role in obesity-related pathologies, is of special interest as a potential marker for predicting increased metabolic risk. CXCL8 expression is increased mainly in the MONW group and correlated directly with C-reactive protein levels.

CONCLUSIONS

PBMC gene expression analysis of CXCL8 or a pool of DEGs may be used to identify early metabolic risk in an apparently healthy population regardless of their BMI, i.e., subjects with OW-OB or MONW phenotype and to apply adequate and personalized nutritional preventive strategies.

Assessing causality between different risk factors and pulmonary embolism: A Mendelian randomization study

Objectives

Mendelian randomization (MR) was used to estimate the causal relationship between body mass index (BMI), ever smoked, heart failure, alcohol intake frequency, inflammatory bowel disease (IBD), and pulmonary embolism (PE). This study aimed to investigate whether there is a causal relationship between BMI, the presence of smoking, heart failure, frequency of alcohol intake, IBD, and PE.

Methods

Pooled data on PE from a published GWAS meta-analysis involving approximately 461,164 participants of European ancestry were selected. A publicly available pooled dataset of BMI (461,460), ever smokers (461,066), heart failure (977,323), IBD (75,000), and frequency of alcohol intake (462,346) was used from another independent GWAS. MR was performed using established analysis methods, including Wald ratios, inverse variance weighted (IVW), weighted median (WM), and MR-Egger. Also, the final expansion was validated with multivariate MR.

Results

In the IVW model, genetically elevated BMI was causally associated with PE [OR = 1.002, 95% CI (1.001, 1004), P = 0.039]. Cochran's Q test was used to detect heterogeneity in the MR-Egger analysis (P = 0.576). Therefore, the effect of gene-level heterogeneity was not considered. In the MR analysis of other risk factors, we observed genes for ever smoking [IVW OR = 1.004, 95% CI (0.997, 1.012)], heart failure [IVW OR = 0.999, 95% CI (0.996, 1.001)], IBD [IVW OR = 1.000, 95% CI (0.999, 1.001)], and frequency of alcohol intake [IVW OR = 1.002, 95% CI (1.000, 1.004)] were not causally associated with PE. Analysis using multivariate MR expansion showed no causal effect of BMI on PE considering the effect of height as well as weight (P = 0.926).

Conclusion

In European populations, a causal relationship exists between BMI and PE: increased BMI leads to PE. In contrast, ever smoking, heart failure, frequency of alcohol intake, and IBD are not directly associated with PE. There was no causal effect of BMI with PE in multivariate Mendelian randomized analysis.

Upregulated NLRP3 inflammasome activation is attenuated by anthocyanins in patients with nonalcoholic fatty liver disease: A case-control and an intervention study

OBJECTIVES

Despite the recent attention focused on the roles of the NLRP3 inflammasome in the pathogenesis of metabolic and inflammatory diseases, little is known about the activation status of NLRP3 inflammasome in patients with nonalcoholic fatty liver disease (NAFLD). The present study aimed to investigate whether inflammasomes activation is upregulated in patients with NAFLD and the upregulation can be attenuated by anthocyanins, which are polyphenols with known anti-inflammatory activities.

METHODS

This study included a case-control study and a randomized controlled intervention trial. In the first part, NAFLD patients and healthy controls were recruited from a cohort of railroad workers. In the second part, NAFLD patients were randomly assigned to receive either capsules of anthocyanins (320 mg daily) or placebo for 12 weeks. A series of genes and factors associated with activation of NLRP3 inflammasome in subjects' plasma and peripheral blood mononuclear cells (PBMCs) were analyzed.

RESULTS

Compared with healthy controls, the mRNA levels of NLRP3 inflammasome components (NLRP3, caspase-1, interleukin (IL)-1β, and IL-18) were significantly upregulated in the PBMCs of NAFLD patients. Consistently, plasma levels of mature IL-1β and IL-18 in NAFLD patients were significantly higher than in controls. After anthocyanin administration, both mRNA expression of NLRP3 inflammasome components (caspase-1, IL-1β, and IL-18) in PBMCs and plasma levels of IL-1β and IL-18 decreased dramatically in NAFLD patients compared with controls.

CONCLUSIONS

This study has demonstrated that the activation of NLRP3 inflammasome is highly increased in NAFLD patients, but it can be markedly suppressed by anthocyanins, which provides a rationale for the development of anti-inflammatory therapies in NAFLD.

A targeted proteomics investigation of the obesity paradox in venous thromboembolism

The obesity paradox, the controversial finding that obesity promotes disease development but protects against sequelae in patients, has been observed in venous thromboembolism (VTE). The aim of this investigation was to identify a body mass-related proteomic signature in VTE patients and to evaluate whether this signature mediates the obesity paradox in VTE patients. Data from the Genotyping and Molecular Phenotyping in Venous ThromboEmbolism Project, a prospective cohort study of 693 VTE patients, were analyzed. A combined end point of recurrent VTE or all-cause death was used. Relative quantification of 444 proteins was performed using high-throughput targeted proteomics technology. Measurements were performed in samples collected during the acute VTE event and at 12-month follow-up. An 11-protein signature (CLEC4C, FABP4, FLT3LG, IL-17C, LEP, LYVE1, MASP1, ST2, THBS2, THBS4, TSLP) for body mass in VTE patients was identified. The signature did not significantly mediate the obesity paradox (change in hazard ratio [HR]: 0.04; likelihood ratio test of nested models = 7.7; P = .74), but its main constituent protein, leptin, was inversely associated with recurrent VTE or death (adjusted HR [95% confidence interval] per standard deviation increase: 0.66 [0.46-0.94]). This relationship was significantly (P = .007) modified by markers of leptin resistance (ie, high body mass index and high circulating matrix metalloproteinase-2 levels). Although the signature did not substantially explain the obesity paradox, leptin appears to be protective against disease recurrence and death in VTE patients. This protective effect was abrogated under conditions of leptin resistance and hence was unrelated to the obesity paradox.

Gene expression profile of peripheral blood mononuclear cells in mild to moderate obesity in dogs

Background

Molecular mechanisms and early diagnosis on the development of mild to moderate of canine obesity are not understood although recent dog obesity is a widespread problem. To understand the differences between normal weight and mild to moderate obesity, the purpose of this study is to investigate the gene expression profiles of peripheral blood mononuclear cells (PBMC) in dogs.

Methods

This study comprised a sample of 12 privately-owned Miniature Dachshund, which were divided into two groups (obese and control) based on body condition scores (BCS). Serum biochemical parameters and PBMC gene expression profiles were compared between groups.

Results

A statistically significant between group differences was recorded for body weight (BW), BCS, serum Insulin and triglyceride (TG) levels (p < 0.05). RNA-seq revealed the upregulated 154 genes and the downregulated 198 genes in obese dogs at more than 3.5-fold change compared with control animals. Hemoglobin subunits alpha- and beta-like were detected in the downregulated genes. RT-PCR analysis showed downregulation of FOLH1, ALAS2 and LOC100855540 genes, and upregulation of BCL2L15 gene, suggesting that the metabolic difference between normal and mild to moderate obesity was involved in the hemoglobin metabolism.

Conclusions

This study revealed significant differences in the gene expression of BCL2L15, FOLH1, ALAS2, and hemoglobin subunits such as LOC100855540 between normal weight and mild to moderate obese dogs, which indicate that these genes may prevent the obesity in dogs and be potentially useful for diagnosis of mild to moderate obesity.

Peripheral Blood Mononuclear Cells Oxidative Stress and Plasma Inflammatory Biomarkers in Adults with Normal Weight, Overweight and Obesity

Background: Obesity is an important pathology in public health worldwide. Obese patients are characterized by higher cardiovascular risk and a pro-inflammatory profile. Objective: To assess the oxidative stress in peripheral blood mononuclear cells (PBMCs) and inflammatory biomarkers in plasma in adults with normal weight, overweight and obesity. Methods: One hundred and fifty adults (55-80-years-old; 60% women) from the Balearic Islands, Spain, were recruited and classified according to body mass index (BMI). Anthropometric measurements were carried out, fasting blood samples were collected and plasma and PBMCs were obtained. Biochemical parameters, hemogram, antioxidant enzyme activities and protein levels, reactive oxygen species production (ROS), malondialdehyde (MDA), and cytokine (tumour necrosis factor, TNFα, and interleukin 6, IL-6) levels were measured. Results: Glycaemia, triglyceridemia, abdominal obesity, and waist-to-height ratio (WHtR) were higher, and HDL-cholesterol was lower in obese patients. MDA and TNFα plasma levels were higher in the obese compared to normal-weight group, while the levels of IL-6 were higher in both obese and overweight subjects with respect to normal-weight peers. The activities of all antioxidant enzymes in PBMCs as well as the production ROS progressively increased with BMI. The protein levels of catalase in PBMCs were higher in obese and glutathione reductase in obese and overweight subjects compared to normal-weight peers. No other differences were observed. Conclusion: The current results show that overweight and obesity are related to an increase in pro-oxidant and proinflammatory status in plasma and PBMCs. The studied biomarkers may be useful for monitoring the progression/reversal of obesity.

Predicting the allergenicity of legume proteins using a PBMC gene expression assay

BACKGROUND

Food proteins differ in their allergenic potential. Currently, there is no predictive and validated bio-assay to evaluate the allergenicity of novel food proteins. The objective of this study was to investigate the potential of a human peripheral blood mononuclear cell (PBMC) gene expression assay to identify biomarkers to predict the allergenicity of legume proteins.

RESULTS

PBMCs from healthy donors were exposed to weakly and strongly allergenic legume proteins (2S albumins, and 7S and 11S globulins from white bean, soybean, peanut, pea and lupine) in three experiments. Possible biomarkers for allergenicity were investigated by exposing PBMCs to a protein pair of weakly (white bean) and strongly allergenic (soybean) 7S globulins in a pilot experiment. Gene expression was measured by RNA-sequencing and differentially expressed genes were selected as biomarkers. 153 genes were identified as having significantly different expression levels to the 7S globulin of white bean compared to soybean. Inclusion of multiple protein pairs from 2S albumins (lupine and peanut) and 7S globulins (white bean and soybean) in a larger study, led to the selection of CCL2, CCL7, and RASD2 as biomarkers to distinguish weakly from strongly allergenic proteins. The relevance of these three biomarkers was confirmed by qPCR when PBMCs were exposed to a larger panel of weakly and strongly allergenic legume proteins (2S albumins, and 7S and 11S globulins from white bean, soybean, peanut, pea and lupine).

CONCLUSIONS

The PBMC gene expression assay can potentially distinguish weakly from strongly allergenic legume proteins within a protein family, though it will be challenging to develop a generic method for all protein families from plant and animal sources. Graded responses within a protein family might be of more value in allergenicity prediction instead of a yes or no classification.

Cancer Signaling Transcriptome Is Upregulated in Type 2 Diabetes Mellitus

We aimed to explore the differences in the whole transcriptome of peripheral blood mononuclear cells between elderly individuals with and without type 2 diabetes (T2D). We conducted a microarray-based transcriptome analysis of 19 individuals with T2D and 15 without. Differentially expressed genes according to linear models were submitted to the Ingenuity Pathway Analysis system to conduct a functional enrichment analysis. We established that diseases, biological functions, and canonical signaling pathways were significantly associated with T2D patients when their logarithms of Benjamini–Hochberg-adjusted p-value were >1.30 and their absolute z-scores were >2.0 (≥2.0 meant “upregulation” and ≤ −2.0 “downregulation”). Cancer signaling pathways were the most upregulated ones in T2D (z-score = 2.63, −log(p-value) = 32.3; 88.5% (n = 906) of the total differentially expressed genes located in these pathways). In particular, integrin (z-score = 2.52, −log(p-value) = 2.03) and paxillin (z-score = 2.33, −log(p-value) = 1.46) signaling pathways were predicted to be upregulated, whereas the Rho guanosine diphosphate (Rho-GDP) dissociation inhibitor signaling pathway was predicted to be downregulated in T2D individuals (z-score = −2.14, −log(p-value) = 2.41). Our results suggest that, at transcriptional expression level, elderly individuals with T2D present an increased activation of signaling pathways related to neoplastic processes, T-cell activation and migration, and inflammation.

Local DNA methylation helps to regulate muscle sirtuin 1 gene expression across seasons and advancing age in gilthead sea bream (Sparus aurata)

Background

Sirtuins (SIRTs) are master regulators of metabolism, and their expression patterns in gilthead sea bream (GSB) reveal different tissue metabolic capabilities and changes in energy status. Since little is known about their transcriptional regulation, the aim of this work was to study for the first time in fish the effect of age and season on sirt gene expression, correlating expression patterns with local changes in DNA methylation in liver and white skeletal muscle (WSM).

Methods

Gene organization of the seven sirts was analyzed by BLAT searches in the IATS-CSIC genomic database (www.nutrigroup-iats.org/seabreamdb/). The presence of CpG islands (CGIs) was mapped by means of MethPrimer software. DNA methylation analyses were performed by bisulfite pyrosequencing. A PCR array was designed for the simultaneous gene expression profiling of sirts and related markers (cs, cpt1a, pgc1α, ucp1, and ucp3) in the liver and WSM of one- and three-year-old fish during winter and summer.

Results

The occurrence of CGIs was evidenced in the sirt1 and sirt3 promoters. This latter CGI remained hypomethylated regardless of tissue, age and season. Conversely, DNA methylation of sirt1 at certain CpG positions within the promoter varied with age and season in the WSM. Among them, changes at several SP1 binding sites were negatively correlated with the decrease in sirt1 expression in summer and in younger fish. Changes in sirt1 regulation match well with variations in feed intake and energy metabolism, as judged by the concurrent changes in the analyzed markers. This was supported by discriminant analyses, which identified sirt1 as a highly responsive element to age- and season-mediated changes in energy metabolism in WSM.

Conclusions

The gene organization of SIRTs is highly conserved in vertebrates. GSB sirt family members have CGI- and non-CGI promoters, and the presence of CGIs at the sirt1 promoter agrees with its ubiquitous expression. Gene expression analyses support that sirts, especially sirt1, are reliable markers of age- and season-dependent changes in energy metabolism. Correlation analyses suggest the involvement of DNA methylation in the regulation of sirt1 expression, but the low methylation levels suggest the contribution of other putative mechanisms in the transcriptional regulation of sirt1.

The Exercise Training Modulatory Effects on the Obesity-Induced Immunometabolic Dysfunctions

Reduced physical activity rate in people's lifestyle is a global concern associated with the prevalence of health disorders such as obesity and metabolic disturbance. Ample evidence has indicated a critical role of the immune system in the aggravation of obesity. The type, duration, and production of adipose tissue-released mediators may change subsequent inactive lifestyle-induced obesity, leading to the chronic systematic inflammation and monocyte/macrophage (MON/MФ) phenotype polarization. Preliminary adipose tissue expansion can be inhibited by changing the lifestyle. In this context, exercise training is widely recommended due to a definite improvement of energy balance and the potential impacts on the inflammatory signaling cascades. How exercise training affects the immune system has not yet been fully elucidated, because its anti-inflammatory, pro-inflammatory, or even immunosuppressive impacts have been indicated in the literature. A thorough understanding of the mechanisms triggered by exercise can suggest a new approach to combat meta-inflammation-induced metabolic diseases. In this review, we summarized the obesity-induced inflammatory pathways, the roles of MON/MФ polarization in adipose tissue and systemic inflammation, and the underlying inflammatory mechanisms triggered by exercise during obesity.

Combined All-Extremity High-Intensity Interval Training Regulates Immunometabolic Responses through Toll-Like Receptor 4 Adaptors and A20 Downregulation in Obese Young Females

Metainflammation and malfunctions of toll-like receptor 4 (TLR4) are related to obesity-induced immunometabolic morbidities. There are almost no studies relating exercise training to the TLR4 pathway and its adaptors and negative regulators. Thirty young women with obesity (exercise group and control group) were included in a 10-week all-extremity combined high-intensity interval training program. The immunomodulatory impacts of exercise on TLR4, its related adaptors (TIR domain-containing adaptor-inducing IFN-β[TRIF], myeloid differentiation factor 88 [MyD88],and tumor receptor-associated factor 6 [TRAF6]), transcriptional factors (nuclear factor [NF]-κB and interferon regulatory factor 3 [IRF3]), and negative regulator (A20) mRNA levels were assessed by real-time PCR. Also, the serum concentration of TLR4 final products (tumor necrosis factor α [TNFα] and interferon γ [IFNγ]) was measured by ELISA. Cardiorespiratory and body composition parameters were tested, as well. There was a significant improvement in body composition and cardiorespiratory fitness. This intervention downregulated TLR4 (from 2.25 ± 1.07 to 0.84 ± 1.01), MyD88 (from 4.53 ± 5.15 to 1.27 ± 0.88), NF-κB (from 1.61 ± 2.03 to 0.23 ± 0.39), IRF3 (from 1.22 ± 0.77 to 0.25 ± 0.36), and A20 (from 0.88 ± 0.59 to 0.22 ± 0.33) levels and reduced the TNFα concentrations (from 22.39 ± 11.43 to 6.26 ± 5.31) significantly in the exercise group, while no statistically significant change was found in TRIF and TRAF6 expression and IFNγ circulating levels. It is concluded that long-term exercise modifies the inflammatory pathways and modulates the immune function at the early stages of inflammation initiation in circulating immune cells. Accordingly, we suggest time-efficient exercise protocols as a possible therapy approach for the prevention of M1 polarization.

Comparative Whole-Transcriptome Profiling of Liver Tissue from Wistar Rats Fed with Diets Containing Different Amounts of Fat, Fructose, and Cholesterol

Differential expression of 30,003 genes was studied in the liver of female Wistar rats fed with isocaloric diets with the excess of fat, fructose, or cholesterol, or their combinations for 62 days using the method of whole-transcriptome profiling on a microchip. Relative mRNA expression levels of the Asah2, Crot, Crtc2, Fmo3, GSTA2, LOC1009122026, LOC102551184, NpY, NqO1, Prom1, Retsat, RGD1305464, Tmem104, and Whsc1 genes were also determined by RT-qPCR. All the tested diets affected differently the key metabolic pathways (KEGGs). Significant changes in the expression of steroid metabolism gene were observed in the liver of animals fed with the tested diets (except the high-fat high fructose diet). Both high-fat and high-fructose diets caused a significant decrease in the expression of squalene synthase (FDFT1 gene) responsible for the initial stage of cholesterol synthesis. On the contrary, in animals fed with the high-cholesterol diet (0.5% cholesterol), expression of the FDFT1 gene did not differ from the control group; however, these animals were characterized by changes in the expression of glucose and glycogen synthesis genes, which could lead to the suppression of glycogen synthesis and gluconeogenesis. At the same time, this group demonstrated different liver tissue morphology in comparison with the animals fed with the high-fructose high-fat diet, manifested as the presence of lipid vacuoles of a smaller size in hepatocytes. The high-fructose and high-fructose high-fat diets affected the metabolic pathways associated with intracellular protein catabolism (endocytosis, phagocytosis, proteasomal degradation, protein processing in the endoplasmic reticulum), tight junctions and intercellular contacts, adhesion molecules, and intracellular RNA transport. Rats fed with the high-fructose high-fat or high-cholesterol diets demonstrated consistent changes in the expression of the Crot, Prom1, and RGD1305464 genes, which reflected a coordinated shift in the regulation of lipid and carbohydrate metabolisms.

Adipocyte browning and resistance to obesity in mice is induced by expression of ATF3

Billions of people have obesity-related metabolic syndromes such as diabetes and hyperlipidemia. Promoting the browning of white adipose tissue has been suggested as a potential strategy, but a drug still needs to be identified. Here, genetic deletion of activating transcription factor 3 (ATF3-/- ) in mice under a high-fat diet (HFD) resulted in obesity and insulin resistance, which was abrogated by virus-mediated ATF3 restoration. ST32da, a synthetic ATF3 inducer isolated from Salvia miltiorrhiza, promoted ATF3 expression to downregulate adipokine genes and induce adipocyte browning by suppressing the carbohydrate-responsive element-binding protein-stearoyl-CoA desaturase-1 axis. Furthermore, ST32da increased white adipose tissue browning and reduced lipogenesis in HFD-induced obese mice. The anti-obesity efficacy of oral ST32da administration was similar to that of the clinical drug orlistat. Our study identified the ATF3 inducer ST32da as a promising therapeutic drug for treating diet-induced obesity and related metabolic disorders.

MicroRNA Profile of HCV Spontaneous Clarified Individuals, Denotes Previous HCV Infection

Factors involved in the spontaneous cleareance of a hepatitis C (HCV) infection are related to both HCV and the interaction with the host immune system, but little is known about the consequences after a spontaneous resolution. The main HCV extrahepatic reservoir is the peripheral blood mononuclear cells (PBMCs), and their transcriptional profile provides us information of innate and adaptive immune responses against an HCV infection. MicroRNAs regulate the innate and adaptive immune responses, and they are actively involved in the HCV cycle. High Throughput sequencing was used to analyze the miRNA profiles from PBMCs of HCV chronic naïve patients (CHC), individuals that spontaneously clarified HCV (SC), and healthy controls (HC). We did not find any differentially expressed miRNAs between SC and CHC. However, both groups showed similar expression differences (21 miRNAs) with respect to HC. This miRNA signature correctly classifies HCV-exposed (CHC and SC) vs. HC, with the has-miR-21-3p showing the best performance. The potentially targeted molecular pathways by these 21 miRNAs mainly belong to fatty acids pathways, although hippo signaling, extracellular matrix (ECM) interaction, proteoglycans-related, and steroid biosynthesis pathways were also altered. These miRNAs target host genes involved in an HCV infection. Thus, an HCV infection promotes molecular alterations in PBMCs that can be detected after an HCV spontaneous resolution, and the 21-miRNA signature is able to identify HCV-exposed patients (either CHC or SC).

Timing of eating in adults across the weight spectrum: Metabolic factors and potential circadian mechanisms

Timing of eating is recognized as a significant contributor to body weight regulation. Disruption of sleep-wake cycles from a predominantly diurnal (daytime) to a delayed (evening) lifestyle leads to altered circadian rhythms and metabolic dysfunction. This article reviews current evidence for timed and delayed eating in individuals of normal weight and those with overweight or obesity: although some findings indicate a benefit of eating earlier in the daytime on weight and/or metabolic outcomes, results have not been uniformly consistent, and more rigorous and longer-duration studies are needed. We also review potential circadian mechanisms underlying the metabolic- and weight-related changes resulting from timed and delayed eating. Further identification of such mechanisms using deep phenotyping is required to determine targets for medical interventions for obesity and for prevention of metabolic syndrome and diabetes, and to inform clinical guidelines regarding eating schedules for management of weight and metabolic disease.

Exploring relationships between body condition score, body fat, activity level and inflammatory biomarkers

Obesity is associated with inflammatory disorders in humans, including degenerative joint disease. While obesity is endemic in horses, its relationship to equine degenerative joint disease has not been explored. The current study sought to describe relationships between: body weight (BW), body condition score (BCS), lameness grade (AAEP), total body fat mass (kg; FM) and fat per cent (FP) [multifrequency bioelectrical impedance analysis (mfBIA)], age, gender, activity level (AL), synovial fluid (SF) and plasma (PL) PGE₂ and glycosaminoglycan (GAG) in horses. During this field investigation, the BCS (of nine) of 54 horses at multiple farms in southern Ontario, Canada, was determined. Horses were categorized as thin (BCS=3/9; n = 6), moderate (BCS=4 or 5/9; n = 18), overweight (BCS=6 or 7/9; n = 19) or obese (BCS=8 or 9/9; n = 11). Total fat mass (kg) and body fat% was measured using mfBIA, lameness was assessed (AAEP lameness scale) and synovial fluid was collected via aseptic arthrocentesis from the left intercarpal joint for assessment of inflammatory biomarkers (PGE₂ , GAG). Means were compared with a one-way ANOVA; correlation coefficients were calculated using a Spearman Rank Order Correlation to reveal correlations between variables. BCS was positively correlated with BW, FM, FP, AL and PL-PGE₂ . BW was also significantly positively correlated with PL-PGE₂ . It is concluded that BCS is significantly correlated with PL-PGE₂ , due in part to the combined effect of AL and body condition. Net inflammatory effects of body fat on risk for joint disease require further study.

Multi-tissue transcriptomic study reveals the main role of liver in the chicken adaptive response to a switch in dietary energy source through the transcriptional regulation of lipogenesis

Background

Because the cost of cereals is unstable and represents a large part of production charges for meat-type chicken, there is an urge to formulate alternative diets from more cost-effective feedstuff. We have recently shown that meat-type chicken source is prone to adapt to dietary starch substitution with fat and fiber. The aim of this study was to better understand the molecular mechanisms of this adaptation to changes in dietary energy sources through the fine characterization of transcriptomic changes occurring in three major metabolic tissues – liver, adipose tissue and muscle – as well as in circulating blood cells.

Results

We revealed the fine-tuned regulation of many hepatic genes encoding key enzymes driving glycogenesis and de novo fatty acid synthesis pathways and of some genes participating in oxidation. Among the genes expressed upon consumption of a high-fat, high-fiber diet, we highlighted CPT1A, which encodes a key enzyme in the regulation of fatty acid oxidation. Conversely, the repression of lipogenic genes by the high-fat diet was clearly associated with the down-regulation of SREBF1 transcripts but was not associated with the transcript regulation of MLXIPL and NR1H3, which are both transcription factors. This result suggests a pivotal role for SREBF1 in lipogenesis regulation in response to a decrease in dietary starch and an increase in dietary PUFA. Other prospective regulators of de novo hepatic lipogenesis were suggested, such as PPARD, JUN, TADA2A and KAT2B, the last two genes belonging to the lysine acetyl transferase (KAT) complex family regulating histone and non-histone protein acetylation. Hepatic glycogenic genes were also down-regulated in chickens fed a high-fat, high-fiber diet compared to those in chickens fed a starch-based diet. No significant dietary-associated variations in gene expression profiles was observed in the other studied tissues, suggesting that the liver mainly contributed to the adaptation of birds to changes in energy source and nutrients in their diets, at least at the transcriptional level. Moreover, we showed that PUFA deposition observed in the different tissues may not rely on transcriptional changes.

Conclusion

We showed the major role of the liver, at the gene expression level, in the adaptive response of chicken to dietary starch substitution with fat and fiber.

Electronic supplementary material

The online version of this article (10.1186/s12864-018-4520-5) contains supplementary material, which is available to authorized users.

Serum and gene expression levels of CT-1, IL-6, and TNF-α after a lifestyle intervention in obese children

BACKGROUND

Inflammation related molecules such as tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), and cardiotrophin-1 (CT-1) are highly expressed in obese individuals and could partly explain some comorbidities associated to obesity. In obese children, lifestyle interventions are able to lower inflammation and reduce cardiovascular risk factors associated with obesity. The aim of the present work was to study changes in inflammation-related molecules serum and peripheral blood mononuclear cells (PBMC) transcript levels after a 10-week lifestyle intervention in obese children and asses their potential association with glucose metabolism.

METHODS

Twenty-three obese children (mean age 11.5 years; 48% males) underwent a 10-week lifestyle not controlled intervention trial. Anthropometric and biochemical measurements were analyzed. Transcript analysis for CT-1, IL-6, and TNF-α in PBMC were performed by RT-PCR. Serum cytokine levels were also measured at baseline and after 10-weeks.

RESULTS

Participants achieved a significant reduction in body adiposity (0.34 decrease in body mass index-standard deviation), total cholesterol, and glucose levels after 10-weeks. A Significant decrease in serum TNF-α and C reactive protein (CRP) were observed. CT-1 transcript levels were significantly reduced (P = .005) after lifestyle intervention, and these changes were significantly correlated with changes in serum CT-1 levels (r = 0.451; P = .031). In multiple regression analysis baseline CT-1 transcript levels were positively associated with final insulin (R² = 0.506; P = .035) and HOMA-IR values (R² = 0.473; P = .034).

CONCLUSIONS

We reported that serum CRP, TNF-α, as well as PBMC CT-1 transcript levels were reduced after lifestyle intervention in obese children. More studies are needed to clarify the role of inflammation-related molecules in glucose metabolism.

Current and future therapies for addressing the effects of inflammation on HDL cholesterol metabolism

Cardiovascular disease (CVD) is a major cause of morbidity and mortality worldwide. Inflammatory processes arising from metabolic abnormalities are known to precipitate the development of CVD. Several metabolic and inflammatory markers have been proposed for predicting the progression of CVD, including high density lipoprotein cholesterol (HDL-C). For ~50 years, HDL-C has been considered as the atheroprotective 'good' cholesterol because of its strong inverse association with the progression of CVD. Thus, interventions to increase the concentration of HDL-C have been successfully tested in animals; however, clinical trials were unable to confirm the cardiovascular benefits of pharmaceutical interventions aimed at increasing HDL-C levels. Based on these data, the significance of HDL-C in the prevention of CVD has been called into question. Fundamental in vitro and animal studies suggest that HDL-C functionality, rather than HDL-C concentration, is important for the CVD-preventive qualities of HDL-C. Our current review of the literature positively demonstrates the negative impact of systemic and tissue (i.e. adipose tissue) inflammation in the healthy metabolism and function of HDL-C. Our survey indicates that HDL-C may be a good marker of adipose tissue health, independently of its atheroprotective associations. We summarize the current findings on the use of anti-inflammatory drugs to either prevent HDL-C clearance or improve the function and production of HDL-C particles. It is evident that the therapeutic agents currently available may not provide the optimal strategy for altering HDL-C metabolism and function, and thus, further research is required to supplement this mechanistic approach for preventing the progression of CVD.

LINKED ARTICLES

This article is part of a themed section on Targeting Inflammation to Reduce Cardiovascular Disease Risk. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.22/issuetoc and http://onlinelibrary.wiley.com/doi/10.1111/bcp.v82.4/issuetoc.

Severe hypertriglyceridemia in Norway: prevalence, clinical and genetic characteristics

BACKGROUND

There is a lack of comprehensive patient-datasets regarding prevalence of severe hypertriglyceridemia (sHTG; triglycerides ≥10 mmol/L), frequency of co-morbidities, gene mutations, and gene characterization in sHTG. Using large surveys combined with detailed analysis of sub-cohorts of sHTG patients, we here sought to address these issues.

METHODS

We used data from several large Norwegian surveys that included 681,990 subjects, to estimate the prevalence. Sixty-five sHTG patients were investigated to obtain clinical profiles and candidate disease genes. We obtained peripheral blood mononuclear cells (PBMC) from six male patients and nine healthy controls and examined expression of mRNAs involved in lipid metabolism.

RESULTS

The prevalence of sHTG was 0.13 (95% CI 0.12-0.14)%, and highest in men aged 40-49 years and in women 60-69 years. Among the 65 sHTG patients, a possible genetic cause was found in four and 11 had experienced acute pancreatitis. The mRNA expression levels of carnitine palmitoyltransferase (CPT)-1A, CPT2, and hormone-sensitive lipase, were significantly higher in patients compared to controls, whereas those of ATP-binding cassette, sub-family G, member 1 were significantly lower.

CONCLUSIONS

In Norway, sHTG is present in 0.1%, carries considerable co-morbidity and is associated with an imbalance of genes involved in lipid metabolism, all potentially contributing to increased cardiovascular morbidity in sHTG.

CXCL-16, IL-17, and bone morphogenetic protein 2 (BMP-2) are associated with overweight and obesity conditions in middle-aged and elderly women

BACKGROUND

The current concept of overweight/obesity is most likely related to a combination of increased caloric intake and decreased energy expenditure. Widespread inflammation, associated with both conditions, appears to contribute to the development of some obesity-related comorbidities. Interventions that directly or indirectly target individuals at high risk of developing obesity have been largely proposed because of the increasing number of overweight/obese cases worldwide. The aim of the present study was to assess CXCL16, IL-17, and BMP-2 plasma factors in middle-aged and elderly women and relate them to an overweight or obese status. In total, 117 women were selected and grouped as eutrophic, overweight, and obese, according to anthropometric parameters. Analyses of anthropometric and circulating biochemical parameters were followed by plasma immunoassays for CXCL-16, IL-17, and BMP-2.

RESULTS

Plasma mediators increased in all overweight and obese individuals, with the exception of BMP-2 in the elderly group, whereas CXCL16 levels were shown to differentiate overweight and obese individuals. Overweight and/or obese middle-aged and elderly individuals presented with high LDL, triglycerides, and glycemia levels. Anthropometric parameters indicating increased-cardiovascular risk were positively correlated with CXCL-16, BMP-2, and IL-17 levels in overweight and obese middle-aged and elderly individuals.

CONCLUSION

This study provides evidence that CXCL-16, IL-17, and BMP-2 are potential plasma indicators of inflammatory status in middle-aged and elderly women; therefore, further investigation of obesity-related comorbidities is recommended. CXCL16, in particular, could be a potential marker for middle-aged and elderly individuals transitioning from eutrophic to overweight body types, which represents an asymptomatic and dangerous condition.

Stability of pro- and anti-inflammatory immune biomarkers for human cohort studies

BACKGROUND

Although discovery research has identified the importance of dozens of pro- and anti-inflammatory immune mediators in the pathogenesis, maintenance, exacerbation and resolution of inflammatory diseases, most human cohort studies have incorporated few or no immunological intermediate phenotypes in their analyses. Significant hindrances have been (1) the limited panel of biomarkers known to be readily detected in healthy human populations and (2) the stability, hence utility, of such biomarkers to repeated analysis.

METHODS

The frequency and stability of 14 plasma biomarkers linked to in vivo immune regulation of allergic and autoimmune inflammatory disorders was determined in 140 healthy pediatric and adult participants. The impact of initial and multiple subsequent freeze/thaw cycles on pro-inflammatory (CCL2, CXCL10, IL-18, TNFα, IL-6), anti-inflammatory (IL-10, sTNF-RII, IL-1Ra), acute phase proteins (CRP, PTX3) and other biomarkers (sST2, IL-1RAcP) was subsequently quantified.

RESULTS

Multiple biomarkers capable of providing an innate immune signature of inflammation were readily detected directly ex vivo in healthy individuals. These biomarker levels were unaffected when comparing paired data sets from freshly obtained, never frozen plasma or serum and matched aliquots despite extensive freeze/thaw cycles. Neither age nor sex affected stability. Similarly, no quantitative differences were found following repetitive analysis of inflammatory biomarkers in culture samples obtained following in vitro stimulation with TLR and RLR ligands.

CONCLUSIONS

A broad panel of in vivo and ex vivo cytokine, chemokine and acute phase protein biomarkers that have been linked to human chronic inflammatory disorders are readily detected in vivo and remain stable for analysis despite multiple freeze thaw cycles. These data provide the foundation and confidence for large scale analyses of panels of inflammatory biomarkers to provide better understanding of immunological mechanisms underlying health versus disease.

Prepregnancy maternal diabetes combined with obesity impairs placental mitochondrial function involving Nrf2/ARE pathway and detrimentally alters metabolism of offspring

Metabolic disorders usually increase the level of reactive oxygen species (ROS) and damage mitochondrial function. The placenta supplies nutrients and hormonal signals to the fetus for regulating fetal metabolism, and is also prone to injury by oxidants. The aim of this study was to determine the effect of pre-existing maternal type 2 diabetes mellitus (DM) combined with obesity on placental mitochondrial function and metabolism disorders of offspring. The study included 96 pregnant women. The women were put into the following groups: healthy women (control, n=24), women with DM (DM, n=24), women with obesity (OB, n=24) and women with both DM and obesity (DM+OB, n=24). The ROS level, mitochondrial content, and the mitochondrial respiratory complex activities of the placenta were measured in the four groups. The expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) was detected by immunofluorescence staining and western blotting. In addition, serum levels of insulin, glucose, leptin, nonesterified fatty acid (NEFA), adiponectin and triglycerides of their offspring were also measured. Maternal DM combined with obesity markedly increased ROS level, reduced mitochondrial DNA (mtDNA) content and mitochondrial respiratory complex I, II-III activities in placenta compared to the placenta from the control group and the DM group. Maternal DM combined with obesity significantly decreased Nrf2 and HO-1 expression. Furthermore, maternal DM combined with obesity influenced the glucose and lipid metabolism in their offspring. In conclusion, women with both DM and obesity detrimentally alter placenta function in oxidative stress regulation, and the Nrf2/ARE (antioxidant responsive element) pathway is involved. This may increase metabolic disturbance susceptibility in their offspring.