Mitochondrial Stress Links Environmental Triggers with Pro-Inflammatory Signaling in Crohn's Disease.

Inflammatory Bowel Diseases (IBD) are a group of chronic, inflammatory disorders of the gut. The incidence and activity of IBD are determined by both genetic and environmental factors. Among these factors, polymorphisms in genes related to autophagy and the consumption of non-steroidal anti-inflammatory drugs (NSAIDs) have been consistently associated with IBD. We show that NSAIDs induce mitochondrial stress and mitophagy in intestinal epithelial cells. In an altered mitophagy context simulating that observed in IBD patients, NSAID-induced mitochondrial stress leads to the release of mitochondrial components, which act as Danger Associated Molecular Patterns with pro-inflammatory potential. Furthermore, colonic organoids from Crohn's disease patients and healthy donors show activation of the mitochondrial Unfolded Protein Response (UPRmt) upon treatment with ibuprofen. Finally, colon biopsies from Crohn's disease patients in remission or with low-to-moderate activity also show expression of genes involved in UPRmt, while patients with severe activity show no increase compared to healthy donors. Our results suggest the involvement of mitochondria in the mechanisms triggering inflammation in IBD after NSAID use. Moreover, our results highlight the clinical relevance of mitochondrial stress and activation of the UPRmt pathway in the pathophysiology of Crohn's disease.

Membrane Vesicles of Toxigenic Clostridioides difficile Affect the Metabolism of Liver HepG2 Cells.

Clostridioides difficile infection (CDI) appears to be associated with different liver diseases. C. difficile secretes membrane vesicles (MVs), which may be involved in the development of nonalcoholic fatty liver disease (NALFD) and drug-induced liver injury (DILI). In this study, we investigated the presence of C. difficile-derived MVs in patients with and without CDI, and analyzed their effects on pathways related to NAFLD and DILI in HepG2 cells. Fecal extracellular vesicles from CDI patients showed an increase of Clostridioides MVs. C. difficile-derived MVs that were internalized by HepG2 cells. Toxigenic C. difficile-derived MVs decreased mitochondrial membrane potential and increased intracellular ROS compared to non-toxigenic C. difficile-derived MVs. In addition, toxigenic C. difficile-derived MVs upregulated the expression of genes related to mitochondrial fission (FIS1 and DRP1), antioxidant status (GPX1), apoptosis (CASP3), glycolysis (HK2, PDK1, LDHA and PKM2) and ß-oxidation (CPT1A), as well as anti- and pro-inflammatory genes (IL-6 and IL-10). However, non-toxigenic C. difficile-derived MVs did not produce changes in the expression of these genes, except for CPT1A, which was also increased. In conclusion, the metabolic and mitochondrial changes produced by MVs obtained from toxigenic C. difficile present in CDI feces are common pathophysiological features observed in the NAFLD spectrum and DILI.

The Metagenomic Composition and Effects of Fecal-Microbe-Derived Extracellular Vesicles on Intestinal Permeability Depend on the Patient's Disease.

The composition and impact of fecal-microbe-derived extracellular vesicles (EVs) present in different diseases has not been analyzed. We determined the metagenomic profiling of feces and fecal-microbe-derived EVs from healthy subjects and patients with different diseases (diarrhea, morbid obesity and Crohn's disease (CD)) and the effect of these fecal EVs on the cellular permeability of Caco-2 cells. The control group presented higher proportions of Pseudomonas and Rikenellaceae_RC9_gut_group and lower proportions of Phascolarctobacterium, Veillonella and Veillonellaceae_ge in EVs when compared with the feces from which these EVs were isolated. In contrast, there were significant differences in 20 genera between the feces and EV compositions in the disease groups. Bacteroidales and Pseudomonas were increased, and Faecalibacterium, Ruminococcus, Clostridium and Subdoligranum were decreased in EVs from control patients compared with the other three groups of patients. Tyzzerella, Verrucomicrobiaceae, Candidatus_Paracaedibacter and Akkermansia were increased in EVs from the CD group compared with the morbid obesity and diarrhea groups. Fecal EVs from the morbid obesity, CD and, mainly, diarrhea induced a significant increase in the permeability of Caco-2 cells. In conclusion, the metagenomic composition of fecal-microbe-derived EVs changes depending on the disease of the patients. The modification of the permeability of Caco-2 cells produced by fecal EVs depends on the disease of the patients.

Oleic acid regulates the circadian rhythm of adipose tissue in obesity.

The effect of oleic acid (OA) on the regulation of the circadian rhythm present in human visceral (VAT) and subcutaneous (SAT) adipose tissue from patients with morbid obesity has not been analyzed yet. VAT and SAT explants from patients with morbid obesity were incubated with OA to analyze the circadian regulation of clock and other genes related to lipid metabolism (SREBP-1c, FAS, LPL and CPT1), and their association with baseline variables and the improvement of these patients after bariatric surgery. There were significant differences in amplitude and acrophase in VAT with respect to SAT. In VAT, body weight negatively correlated with BMAL1 and CRY1 amplitude, and REVERBα acrophase; body mass index (BMI) negatively correlated with REVERBα acrophase; and waist circumference negatively correlated with PER3 acrophase. In SAT, BMI negatively correlated with CLOCK amplitude, and CLOCK, REVERBα and CRY2 MESOR; and waist circumference negatively correlated with PER3 amplitude and acrophase. A greater short-term improvement of body weight, BMI and waist circumference in patients with morbid obesity after bariatric surgery was associated with a lower CRY1 and CRY2 amplitude and an earlier PER1 and PER3 acrophase in SAT. OA produced a more relevant circadian rhythm and increased the amplitude of most clock genes and lipid metabolism-related genes. OA regulated the acrophase of most clock genes in VAT and SAT, placing CLOCK/BMAL1 in antiphase with regard to the other genes. OA increased the circadian rhythmicity, although with slight differences between adipose tissues. These differences could determine its different behavior in obesity.

Morbid Obesity in Women Is Associated with an Altered Intestinal Expression of Genes Related to Cancer Risk and Immune, Defensive, and Antimicrobial Response.

BACKGROUND: Little is known about the relation between morbid obesity and duodenal transcriptomic changes. We aimed to identify intestinal genes that may be associated with the development of obesity regardless of the degree of insulin resistance (IR) of patients. MATERIAL AND METHODS: Duodenal samples were assessed by microarray in three groups of women: non-obese women and women with morbid obesity with low and high IR. RESULTS: We identified differentially expressed genes (DEGs) associated with morbid obesity, regardless of IR degree, related to digestion and lipid metabolism, defense response and inflammatory processes, maintenance of the gastrointestinal epithelium, wound healing and homeostasis, and the development of gastrointestinal cancer. However, other DEGs depended on the IR degree. We mainly found an upregulation of genes involved in the response to external organisms, hypoxia, and wound healing functions in women with morbid obesity and low IR. CONCLUSIONS: Regardless of the degree of IR, morbid obesity is associated with an altered expression of genes related to intestinal defenses, antimicrobial and immune responses, and gastrointestinal cancer. Our data also suggest a deficient duodenal immune and antimicrobial response in women with high IR.

EVOO Promotes a Less Atherogenic Profile Than Sunflower Oil in Smooth Muscle Cells Through the Extracellular Vesicles Secreted by Endothelial Cells.

Background: Little is known about the effect of extra virgin olive (EVOO) and sunflower oil (SO) on the composition of extracellular vesicles (EVs) secreted by endothelial cells and the effects of these EVs on smooth muscle cells (SMCs). These cells play an important role in the development of atherosclerosis. Methods: We evaluated the effects of endothelial cells-derived EVs incubated with triglyceride-rich lipoproteins obtained after a high-fat meal with EVOO (EVOO-EVs) and SO (SO-EVs), on the transcriptomic profile of SMCs. Results: We found 41 upregulated and 19 downregulated differentially expressed (DE)-miRNAs in EVOO-EVs. Afterwards, SMCs were incubated with EVOO-EVs and SO-EVs. SMCs incubated with SO-EVs showed a greater number of DE-mRNA involved in pathways related to cancer, focal adhesion, regulation of actin cytoskeleton, and MAPK, toll-like receptor, chemokine and Wnt signaling pathways than in SMCs incubated with EVOO-EVs. These DE-mRNAs were involved in biological processes related to the response to endogenous stimulus, cell motility, regulation of intracellular signal transduction and cell population proliferation. Conclusion: EVOO and SO can differently modify the miRNA composition of HUVEC-derived EVs. These EVs can regulate the SMCs transcriptomic profile, with SO-EVs promoting a profile more closely linked to the development of atherosclerosis than EVOO-EVs.

Influence of Factors Altering Gastric Microbiota on Bariatric Surgery Metabolic Outcomes.

Little is known about the influence of gastric microbiota on host metabolism, even though the stomach plays an important role in the production of hormones involved in body weight regulation and glucose homeostasis. Proton pump inhibitors (PPIs) and Helicobacter pylori alter gut microbiota, but their impact on gastric microbiota in patients with obesity and the influence of these factors on the metabolic response to bariatric surgery is not fully understood. Forty-one subjects with morbid obesity who underwent sleeve gastrectomy were included in this study. The H. pylori group was established by the detection of H. pylori using a sequencing-based method (n = 16). Individuals in whom H. pylori was not detected were classified according to PPI treatment. Gastric biopsy specimens were obtained during surgery and were analyzed by a high-throughput-sequencing method. Patients were evaluated at baseline and 3, 6, and 12 months after surgery. ß-Diversity measures were able to cluster patients according to their gastric mucosa-associated microbiota composition. H. pylori and PPI treatment are presented as two important factors for gastric mucosa-associated microbiota. H. pylori reduced diversity, while PPIs altered ß-diversity. Both factors induced changes in the gastric mucosa-associated microbiota composition and its predicted functions. PPI users showed lower percentages of change in the body mass index (BMI) in the short term after surgery, while the H. pylori group showed higher glucose levels and lower percentages of reduction in body weight/BMI 1 year after surgery. PPIs and H. pylori colonization could modify the gastric mucosa-associated microbiota, altering its diversity, composition, and predicted functionality. These factors may have a role in the metabolic evolution of patients undergoing bariatric surgery. IMPORTANCE The gut microbiota has been shown to have an impact on host metabolism. In the stomach, factors like proton pump inhibitor treatment and Helicobacter pylori haven been suggested to alter gut microbiota; however, the influence of these factors on the metabolic response to bariatric surgery has not been fully studied. In this study, we highlight the impact of these factors on the gastric microbiota composition. Moreover, proton pump inhibitor treatment and the presence of Helicobacter pylori could have an influence on bariatric surgery outcomes, mainly on body weight loss and glucose homeostasis. Deciphering the relationship between gastric hormones and gastric microbiota and their contributions to bariatric surgery outcomes paves the way to develop gut manipulation strategies to improve the metabolic success of bariatric surgery.

An Isolated Dose of Extra-Virgin Olive Oil Produces a Better Postprandial Gut Hormone Response, Lipidic, and Anti-Inflammatory Profile that Sunflower Oil: Effect of Morbid Obesity.

INTRODUCTION: This study evaluates the effects of 25 mL of three types of oils [extra-virgin olive oil (EVOO), olive oil (OO), and sunflower oil (SO)] on postprandial (3 h) satiety markers and variables related to metabolic status and inflammation in non-obese patients (n = 6) and in those with morbid obesity (n = 6), before and 1 year after Roux-en-Y gastric by-pass (RYGB). METHODS AND RESULTS: After EVOO intake, serum acylated ghrelin decreases and GLP1 increases more than with OO and SO. EVOO causes a higher increase of insulin and lower postprandial hypertriglyceridemia and free fatty acid levels than with OO and SO. EVOO decreases TNFα and IL6 expression in peripheral blood mononuclear cells, with OO inducing intermediate effects and SO inducing an increase of these proinflammatory markers. These results are observed in non-obese patients and in those with morbid obesity after RYGB. However, patients with morbid obesity before RYGB show a profound alteration of this response. CONCLUSION: EVOO produces more beneficial effects than OO, which has lower amounts of minor components, and SO, which has PUFA as its main component. RYGB produces an improvement in the metabolic response to all three types of oils in patients with morbid obesity.

Oleic acid restores the rhythmicity of the disrupted circadian rhythm found in gastrointestinal explants from patients with morbid obesity.

BACKGROUND & AIMS: We investigated whether oleic acid (OA), one of the main components of the Mediterranean diet, participates in the regulation of the intestinal circadian rhythm in patients with morbid obesity. METHODS: Stomach and jejunum explants from patients with morbid obesity were incubated with oleic acid to analyze the regulation of clock genes. RESULTS: Stomach explants showed an altered circadian rhythm in CLOCK, BMAL1, REVERBα, CRY1, and CRY2, and an absence in PER1, PER2, PER3 and ghrelin (p > 0.05). OA led to the emergence of rhythmicity in PER1, PER2, PER3 and ghrelin (p < 0.05). Jejunum explants showed an altered circadian rhythm in CLOCK, BMAL1, PER1 and PER3, and an absence in PER2, REVERBα, CRY1, CRY2 and GLP1 (p > 0.05). OA led to the emergence of rhythmicity in PER2, REVERBα, CRY1 and GLP1 (p < 0.05), but not in CRY2 (p > 0.05). OA restored the rhythmicity of acrophase and increased the amplitude for most of the genes studied in stomach and jejunum explants. OA placed PER1, PER2, PER3, REVERBα, CRY1 and CRY2 in antiphase with regard to CLOCK and BMAL1. CONCLUSIONS: There is an alteration in circadian rhythm in stomach and jejunum explants in morbid obesity. OA restored the rhythmicity of the genes related with circadian rhythm, ghrelin and GLP1, although with slight differences between tissues, which could determine a different behaviour of the explants from jejunum and stomach in obesity.

Oleic Acid Protects Against Insulin Resistance by Regulating the Genes Related to the PI3K Signaling Pathway.

BACKGROUND: The effects of different types of fatty acids on the gene expression of key players in the IRS1/PI3K signaling pathway have been poorly studied. MATERIAL AND METHODS: We analyzed IRS1, p85α, and p110ß mRNA expression and the fatty acid composition of phospholipids in visceral adipose tissue from patients with morbid obesity and from non-obese patients. Moreover, we analyzed the expression of those genes in visceral adipocytes incubated with oleic, linoleic, palmitic and dosahexaenoic acids. RESULTS: We found a reduced IRS1 expression in patients with morbid obesity, independent of insulin resistance, and a reduced p110ß expression in those with lower insulin resistance. A positive correlation was found between p85α and stearic acid, and between IRS1 and p110ß with palmitic and dosahexaenoic acid. In contrast, a negative correlation was found between p85α and oleic acid, and between IRS1 and p110ß with linoleic, arachidonic and adrenic acid. Incubation with palmitic acid decreased IRS1 expression. p85α was down-regulated after incubation with oleic and dosahexaenoic acid and up-regulated with palmitic acid. p110ß expression was increased and decreased after incubation with oleic and palmitic acid, respectively. The ratio p85α/p110ß was decreased by oleic and dosahexaenoic acid and increased by palmitic acid. CONCLUSIONS: Our in vitro results suggest a detrimental role of palmitic acid on the expression of gene related to insulin signaling pathway, with oleic acid being the one with the higher and more beneficial effects. DHA had a slight beneficial effect. Fatty acid-induced regulation of genes related to the IRS1/PI3K pathway may be a novel mechanism by which fatty acids regulate insulin sensitivity in visceral adipocytes.

Different Expression of Duodenal Genes Related to Insulin Resistance Between Nonobese Women and Those with Severe Obesity.

OBJECTIVE: The study aim was to identify changes in duodenal gene expression associated with the development of insulin resistance according to the BMI of women. METHODS: Duodenal samples were assessed by microarray in four groups of women, nonobese women and women with severe obesity, with both low and high insulin resistance. RESULTS: There was a group of shared downregulated differentially expressed genes (DEGs) related to tissue homeostasis and antimicrobial humoral response in women with higher insulin resistance both with severe obesity and without obesity. In the exclusive DEGs found in severe obesity, downregulated DEGs related to the regulation of the defense response to bacterium and cell adhesion, involving pathways related to the immune system, inflammation, and xenobiotic metabolism, were observed. In the exclusive DEGs from nonobese women with higher insulin resistance, upregulated DEGs mainly related to the regulation of lipoprotein lipase activity, very low-density lipoprotein particle remodeling, lipid metabolic process, antigen processing, and the presentation of peptide antigen were found. CONCLUSIONS: Independent of BMI, higher insulin resistance was associated with a downregulation of duodenal DEGs mainly related to the immune system, inflammation, and xenobiotic metabolism. Also, intestinal lipoprotein metabolism may have a certain relevance in the regulation of insulin resistance in nonobese women.

Mucosa-associated microbiota in the jejunum of patients with morbid obesity: alterations in states of insulin resistance and metformin treatment.

BACKGROUND: Stool samples have been widely used to evaluate gut microbiota; however, little is known about the composition of human small intestinal microbiota and the alterations provoked by insulin resistance. OBJECTIVE: To describe the composition of jejunal microbiota in morbidly obese patients, as well as its link with insulin resistance and metformin treatment. SETTING: Virgen de la Victoria University Hospital and Regional University Hospital, Málaga, Spain. METHODS: Jejunal biopsies from 46 morbidly obese patients were analyzed by next-generation sequencing method. Patients were classified in the following 3 groups: low homeostasis model assessment of insulin resistance index (HOMA-IR) value, high HOMA-IR value, and metformin-treated type 2 diabetes patients (T2D-metf). RESULTS: Richness (q = .011) together with Proteobacteria (W = 2), Fusobacteria (W = 2), and Bacteroidetes (W = 1) phyla were significantly higher in high HOMA-IR compared with low HOMA-IR group. At family level, several differences were found between low HOMA-IR and T2D-metf group, being the most important the higher abundance of Halomonadacea in T2D-metf group (W = 22). PICRUSt analysis showed that predicted genes involved in trimethylamine-N-oxide biosynthesis pathway could be increased in jejunal microbiota of T2D-metf group compared with the low HOMA-IR group, while indole biosynthesis pathway could be increased in the low HOMA-IR group compared with the high HOMA-IR group. CONCLUSION: An increase in richness and an enrichment in Proteobacteria, Fusobacteria, and Bacteroidetes was observed in jejunal from morbidly obese patients with high insulin resistance. Halomonadaceae family was significantly increased in metformin-treated patients. Functional analysis of predicted metagenome suggests that trimethylamine-N-oxide biosynthesis pathway could be increased in the jejunal microbiota of T2D-meft group, while indole biosynthesis pathway could be increased in low HOMA-IR group. These results contribute to the increase in the scarce knowledge about the mucosal microbiota of the hardly accessible small intestine.

Jejunal Insulin Signalling Is Increased in Morbidly Obese Subjects with High Insulin Resistance and Is Regulated by Insulin and Leptin.

Little is known about the jejunal insulin signalling pathways in insulin resistance/diabetes states and their possible regulation by insulin/leptin. We study in jejunum the relation between insulin signalling and insulin resistance in morbidly obese subjects with low (MO-low-IR) or with high insulin resistance (MO-high-IR), and with type 2 diabetes treated with metformin (MO-metf-T2DM)), and the effect of insulin/leptin on intestinal epithelial cells (IEC). Insulin receptor substrate-1 (IRS1) and the catalytic p110ß subunit (p110ß) of phosphatidylinositol 3-kinase (PI3K) were higher in MO-high-IR than in MO-low-IR. The regulatory p85α subunit of PI3K (p85α)/p110ß ratio was lower in MO-high-IR and MO-metf-T2DM than in MO-low-IR. Akt-phosphorylation in Ser473 was reduced in MO-high-IR compared with MO-low-IR. IRS1 and p110-ß were associated with insulin and leptin levels. The improvement of body mass index (BMI) and HOMA-IR (homeostasis model assessment of insulin resistance index) after bariatric surgery was associated with a higher IRS1 and a lower p85α/p110ß ratio. IEC (intestinal epithelial cells) incubation with a high glucose + insulin dose produced an increase of p85α and p110ß. High dose of leptin produced an increase of IRS1, p85α and p110ß. In conclusion, despite the existence of insulin resistance, the jejunal expression of genes involved in insulin signalling was increased in MO-high-IR. Their expressions were regulated mainly by leptin. IRS1 and p85α/p110ß ratio was associated with the evolution of insulin resistance after bariatric surgery.

A lower duodenal immune response is associated with an increase of insulin resistance in patients with morbid obesity.

OBJECTIVE: The intestinal immune response could play an important role in obesity-related comorbidities. We aim to study the profile of duodenal cytokines and chemokines in patients with morbid obesity (MO), its relation with insulin resistance (IR) and the intake of metformin, and with the evolution of MO after sleeve gastrectomy (SG). RESEARCH DESIGN AND METHODS: Duodenal levels of 24 cytokines and 9 chemokines were analyzed in 14 nonobese and in 54 MO who underwent SG: with lower IR (MO-lower-IR), with higher IR (MO-higher-IR), and with type 2 diabetes treated with metformin (MO-metf-T2DM). RESULTS: MO-lower-IR had higher levels of cytokines related to Th1, Th2, Th9, Th17, Th22, M1 macrophages, and chemokines involved in the recruitment of macrophages and T-lymphocytes (p < 0.05), and total (CD68 expression) and M1 macrophages (ITGAX expression) (p < 0.05) when compared with nonobese patients, but with a decrease in M2 macrophages (MRC1 expression) (p < 0.05). In MO-higher-IR, these chemokines and cytokines decreased and were similar to those found in nonobese patients. In MO-metf-T2DM, only IL-4 (Th2) and IL-22 (Th22) increased their levels with regard to MO-higher-IR (p < 0.05). In MO-higher-IR and MO-metf-T2DM, there was a decrease of CD68 expression (p < 0.05) while ITGAX and MRC1 were similar with regard to MO-lower-IR. We found an association between CXCL8, TNFß and IL-2 with the evolution of body mass index (BMI) after SG (p < 0.05). CONCLUSIONS: There is an association between a higher IR and a lower duodenal immune response in MO, with a slight increase in those patients with metformin treatment. Intestinal immune response could be involved in the evolution of BMI after SG.

Increased PON lactonase activity in morbidly obese patients is associated with impaired lipid profile.

AIMS: The paraoxonase-1 (PON1) enzyme could play an important role in the anti-oxidant capacity of high-density lipoprotein. However, there are no studies which analyse the evolution of the three activities of PON1 (PON arylesterase, PON paraoxonase and PON lactonase) after Roux-en-Y Gastric Bypass (RYGB) in morbidly obese subjects. We analysed the association of PON concentration and activities with the evolution of morbidly obese subjects who underwent RYGB, and its relationship with biochemical variables and different atherogenic indices. METHODS: Twenty-seven non-obese and 82 morbidly obese subjects were studied before and 6 months after RYGB. RESULTS: Before RYGB, morbidly obese subjects had a lower PON1 concentration (P < 0.05) and higher PON lactonase activity (P < 0.001) than non-obese subjects, with no differences in PON arylesterase and PON paraoxonase activities. After RYGB, PON1 concentration (P < 0.05) and PON lactonase activity (P < 0.001) decreased with regard to the presurgery state. PON lactonase activity correlated with the atherogenic index of plasma before (r = 0.19, P = 0.047) and after RYGB (r = 0.27, P = 0.035). In different multiple lineal regression analysis models, presurgery PON lactonase activity was associated with total cholesterol (ß = 0.909, P < 0.001), LDL (ß = 0.632, P = 0.006) and DBP (ß = 0.230, P = 0.030) (R2  = 0.295), postsurgery PON lactonase activity was associated with esterified cholesterol (ß = 0.362, P = 0.011) (R2  = 0.131), and the change (Δ) in PON lactonase activity after RYGB was associated with Δesterified cholesterol (ß = 0.304, P = 0.030) (R2  = 0.093). CONCLUSIONS: PON lactonase activity is associated with the presence of morbid obesity and with an impaired lipid profile. All associations found could indicate the relationship between PON lactonase activity and the development of atherosclerosis.

The changes in the transcriptomic profiling of subcutaneous adipose tissue after bariatric surgery depend on the insulin resistance state.

BACKGROUND: The changes that are produced in the gene expression of subcutaneous adipose tissue after Roux-en-Y gastric bypass are not yet fully known. OBJECTIVE: To identify the changes in the subcutaneous adipose tissue gene expression of morbidly obese women with low insulin resistance (MO-low-IR) and high insulin resistance (MO-high-IR) to find a relationship with measured obesity-related co-morbidities. SETTING: A university hospital. METHODS: Subcutaneous adipose tissue samples were assessed by microarray analysis before and 2 years after Roux-en-Y gastric bypass in MO-low-IR and MO-high-IR patients. RESULTS: There is a group of shared differentially expressed genes (DEG) in both MO-low-IR and MO-high-IR, also there is a group of exclusive DEG in MO-low-IR and another group in MO-high-IR. In MO-high-IR, the downexpressed DEG are related to the regulation of transcription and are involved in the pathways related to cytokine-cytokine receptor interaction, cancer, phosphatidylinositol 3-kinase-protein kinase B signaling, human T-lymphotropic virus I infection, chemokine signaling, and Janus kinase/signal transducers and activators of transcription signaling. In MO-low-IR, the overexpressed DEG are related to carbohydrate metabolic processes, the downexpressed DEG to the glycosaminoglycan metabolic process and regulation of translation, and the pathways are related to phosphatidylinositol 3-kinase-protein kinase B signaling and metabolic pathways. The fold change of DEG mainly correlates with the percentage of change (Δ) of waist, Δhip, Δglucose, and Δtriglycerides. These DEG were mainly related to cancer, inflammation/immune regulation, metabolic pathways, ribonucleic acid/deoxyribonucleic acid regulation, virus infection, and regulation of cellular proliferation. CONCLUSIONS: This study suggests a potential association between high insulin resistance and the expression of genes related to cancer and chronic immune activation/inflammation.

Tissue-Specific Phenotype and Activation of iNKT Cells in Morbidly Obese Subjects: Interaction with Adipocytes and Effect of Bariatric Surgery.

BACKGROUND: The immune response of visceral adipose tissue (VAT) in obesity, in particular the role of invariant natural killer T (iNKT) cells, has not yet been fully elucidated. OBJECTIVE: To characterize iNKT cells and its activation status in VAT and peripheral blood mononuclear cells (PBMC) in morbidly obese subjects (MO), and to analyze their association with metabolic parameters. SUBJECTS AND METHODS: Twenty non-obese and 20 MO subjects underwent Roux-en-Y gastric bypass (RYGB) and were studied before and 6 months after RYGB. VAT and PBMC were obtained. RESULTS: A decrease in VAT iNKT cells from MO was found, however, not in PBMC. Visceral adipocytes from MO presented increased CD1d expression (p = 0.032). MO presented an increase in early activated CD69+ iNKT cells in PBMC before RYGB (p < 0.001), but not after RYGB nor in VAT, and an increase in later activated CD25+ iNKT in VAT (p = 0.046), without differences in PBMC. The co-expression of early and later markers (CD69+CD25+) in iNKT cells was increased in MO in VAT (p = 0.050) and PBMC (p = 0.006), decreasing after RYGB (p = 0.050). CD69+ iNKT and CD69+CD25+ iNKT cells in PBMC after RYGB correlated negatively with glucose, insulin, and insulin resistance levels. CONCLUSIONS: There is a tissue-specific phenotype and activation of iNKT cells in VAT in morbid obesity, which could be involved in VAT immunometabolism dysregulation. Also, the increase in CD1d expression could be to offset the lack of VAT iNKT cells.

The pro-/anti-inflammatory effects of different fatty acids on visceral adipocytes are partially mediated by GPR120.

PURPOSE: This study examines whether G-protein coupled receptor 120 (GPR120) is involved in the pro-/anti-inflammatory effects of different types of fatty acids (FAs) in human visceral adipocytes, and whether these effects may be altered in obesity, a state with a chronic inflammation. METHODS: Pro-/anti-inflammatory effects of palmitic, oleic, linoleic and docosahexaenoic acids on human visceral adipocytes were tested in mature adipocytes from non-obese and morbidly obese (MO) subjects. Also, the effects of these FAs were tested when the GPR120 gene was silenced. RESULTS: In adipocytes from non-obese subjects, palmitic and linoleic acids increased TNF-α and IL-6 mRNA expression (p < 0.05), and decreased IL-10 and adiponectin expression (p < 0.05). However, oleic and docosahexaenoic acids (DHA) produced the opposite effect (p < 0.05). In adipocytes from MO subjects, all FAs used increased TNF-α and IL-6 expression (p < 0.05). Palmitic and linoleic acids decreased IL-10 and adiponectin expression (p < 0.05), but oleic acid and DHA did not have significant effects. Only oleic acid increased adiponectin expression (p < 0.05). The effects of FAs on TNF-α, IL-6, IL-10 and adiponectin expression in non-obese and MO subjects were significantly annulled when the GPR120 gene was silenced in visceral adipocytes differentiated from human mesenchymal stem cells. CONCLUSIONS: FAs are capable of directly acting on visceral adipocytes to modulate differently TNF-α, IL-6, IL-10 and adiponectin expression, with a different and greater effect in MO subjects. These effects are largely annulled when GPR120 expression was silenced, which suggests that they could be mediated by GPR120.

Increased levels of tumour necrosis factor alpha (TNFα) but not transforming growth factor-beta 1 (TGFß1) are associated with the severity of congenital hydrocephalus in the hyh mouse.

AIMS: Here, we tested the hypothesis that glial responses via the production of cytokines such as transforming growth factor-beta 1 (TGFß1) and tumour necrosis factor alpha (TNFα), which play important roles in neurodegenerative diseases, are correlated with the severity of congenital hydrocephalus in the hyh mouse model. We also searched for evidence of this association in human cases of primary hydrocephalus. METHODS: Hyh mice, which exhibit either severe or compensated long-lasting forms of hydrocephalus, were examined and compared with wild-type mice. TGFß1, TNFα and TNFαR1 mRNA levels were quantified using real-time PCR. TNFα and TNFαR1 were immunolocalized in the brain tissues of hyh mice and four hydrocephalic human foetuses relative to astroglial and microglial reactions. RESULTS: The TGFß1 mRNA levels were not significantly different between hyh mice exhibiting severe or compensated hydrocephalus and normal mice. In contrast, severely hydrocephalic mice exhibited four- and two-fold increases in the mean levels of TNFα and TNFαR1, respectively, compared with normal mice. In the hyh mouse, TNFα and TNFαR1 immunoreactivity was preferentially detected in astrocytes that form a particular periventricular reaction characteristic of hydrocephalus. However, these proteins were rarely detected in microglia, which did not appear to be activated. TNFα immunoreactivity was also detected in the glial reaction in the small group of human foetuses exhibiting hydrocephalus that were examined. CONCLUSIONS: In the hyh mouse model of congenital hydrocephalus, TNFα and TNFαR1 appear to be associated with the severity of the disease, probably mediating the astrocyte reaction, neurodegenerative processes and ischaemia.

Astrocytes acquire morphological and functional characteristics of ependymal cells following disruption of ependyma in hydrocephalus.

Hydrocephalic hyh mutant mice undergo a programmed loss of the neuroepithelium/ependyma followed by a reaction of periventricular astrocytes, which form a new cell layer covering the denuded ventricular surface. We present a comparative morphological and functional study of the newly formed layer of astrocytes and the multiciliated ependyma of hyh mice. Transmission electron microscopy, immunocytochemistry for junction proteins (N-cadherin, connexin 43) and proteins involved in permeability (aquaporin 4) and endocytosis (caveolin-1, EEA1) were used. Horseradish peroxidase (HRP) and lanthanum nitrate were used to trace the intracellular and paracellular transport routes. The astrocyte layer shares several cytological features with the normal multiciliated ependyma, such as numerous microvilli projected into the ventricle, extensive cell-cell interdigitations and connexin 43-based gap junctions, suggesting that these astrocytes are coupled to play an unknown function as a cell layer. The ependyma and the astrocyte layers also share transport properties: (1) high expression of aquaporin 4, caveolin-1 and the endosome marker EEA1; (2) internalization into endocytic vesicles and early endosomes of HRP injected into the ventricle; (3) and a similar paracellular route of molecules moving between CSF, the subependymal neuropile and the pericapillary space, as shown by lanthanum nitrate and HRP. A parallel analysis performed in human hydrocephalic foetuses indicated that a similar phenomenon would occur in humans. We suggest that in foetal-onset hydrocephalus, the astrocyte assembly at the denuded ventricular walls functions as a CSF-brain barrier involved in water and solute transport, thus contributing to re-establish lost functions at the brain parenchyma-CSF interphase.