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In polycystic ovary syndrome (PCOS), oxidative stress is implicated in the development of β-cell dysfunction. However, the role of mononuclear cell (MNC)-derived inflammation in this process is unclear. We determined the relationship between β-cell function and MNC-derived nuclear factor-κB (NF-κB) activation and tumor necrosis factor-α (TNF-α) secretion in response to a 2-h 75-g oral glucose tolerance test (OGTT) in normoglycemic women with PCOS (15 lean, 15 obese) and controls (16 lean, 14 obese). First- and second-phase β-cell function was calculated as glucose-stimulated insulin secretion (insulin/glucose area under the curve for 0–30 and 60–120 min, respectively) × insulin sensitivity (Matsuda Index derived from the OGTT). Glucose-stimulated NF-κB activation and TNF-α secretion from MNC, and fasting plasma thiobarbituric acid-reactive substances (TBARS) and high-sensitivity C-reactive protein (hs-CRP) were also assessed. In obese women with PCOS, first- and second-phase β-cell function was lower compared with lean and obese controls. Compared with lean controls, women with PCOS had greater change from baseline in NF-κB activation and TNF-α secretion, and higher plasma TBARS. β-Cell function was inversely related to NF-κB activation (1st and 2nd) and TNF-α secretion (1st), and plasma TBARS and hs-CRP (1st and 2nd). First- and second-phase β-cell function also remained independently linked to NF-κB activation after adjustment for body fat percentage and TBARS. In conclusion, β-cell dysfunction in PCOS is linked to hyperglycemia-induced NF-κB activation from MNC and systemic inflammation. These data suggest that in PCOS, inflammation may play a role in impairing insulin secretion before the development of overt hyperglycemia.

Context:Excess adipose tissue is a source of inflammation. Polycystic ovary syndrome (PCOS) is a proinflammatory state and is often associated with excess abdominal adiposity (AA) alone and/or frank obesity.Objective:To determine the effect of glucose ingestion on cytokine release from mononuclear cells (MNC) in women with PCOS with and without excess AA and/or obesity.Design:A cross-sectional study.Setting:Academic medical center.Patients:Twenty-three women with PCOS (seven normal weight with normal AA, eight normal weight with excess AA, eight obese) and 24 ovulatory controls (eight normal weight with normal AA, eight normal weight with excess AA, eight obese).Intervention:Three-hour 75-g oral glucose tolerance test (OGTT).Main Outcome Measures:Body composition was measured by dual energy x-ray absorptiometry. Insulin sensitivity was derived from the OGTT (ISOGTT). TNFα, IL-6, and IL-1β release was measured in supernatants of cultured MNC isolated from blood samples drawn while fasting and 2 hours after glucose ingestion.Results:Insulin sensitivity was lower in obese subjects regardless of PCOS status and in normal-weight women with PCOS compared with normal-weight controls regardless of body composition status. In response to glucose ingestion, MNC-derived TNFα, IL-6, and IL-1β release decreased in both normal-weight control groups but failed to suppress in either normal-weight PCOS group and in obese women regardless of PCOS status. For the combined groups, the cytokine responses were negatively correlated with insulin sensitivity and positively correlated with abdominal fat and androgens.Conclusions:Women with PCOS fail to suppress MNC-derived cytokine release in response to glucose ingestion, and this response is independent of excess adiposity. Nevertheless, a similar response is also a feature of obesity per se. Circulating MNC and excess adipose tissue are separate and distinct sources of inflammation in this population.

Objective: Hydrocortisone, at a low dose (100 mg), induces an anti-inflammatory response including inducing IkBα and suppressing intranuclear NFκB and AP-1 binding and the expression of pro-inflammatory mediators like MMPs. We have now investigated the effect of a high dose of hydrocortisone (300mg=60 mg prednisolone) on NFκB binding and the expression of TLRs, the mediators of TLR signal transduction, MyD88 and TRIF and HMG-B1. Design and Subjects: A 300mg of hydrocortisone or saline was injected intravenously in ten normal subjects during 2 separate visits, in a randomized crossover study. Blood samples were obtained at 0, 1, 4, 6 and 24h after the injection and mononuclear cells (MNC) were prepared. Results: There was a significant increase in glucose (from 92±4 to 116±6 mg/dl), insulin (from 4.5±0.7 to 5.3±0.8 mU/ml) and FFA concentrations (from 0.38±0.1 to 0.80±0.15mM) following the administration of hydrocortisone compared to placebo treatment. While NFκB binding and the mRNA expression of MyD88, TRIF, chemokines and chemokine receptors were suppressed significantly in MNC, there was a paradoxical increase in the mRNA expression of TLR 2, 5 and 9 and HMG-B1 was increased by 103±24%, 107±19%, 56±13% and 58±12% above the baseline, respectively in the MNC. Plasma concentrations of HMG-B1 and MMP-9 increased by 37±12% and 125±22%, respectively, while TNF-α concentrations fell by 27±9%. Conclusion: While this high dose of hydrocortisone exerts a powerful anti-inflammatory effect, it also exerts certain proinflammatory effects mainly on TLRs expression. The known pro-inflammatory effects of glucose and FFAs may have contributed to these effects. These paradoxical pro-inflammatory effects may account for the inability of these drugs to show benefit in clinical trials of septicemia and other severe pro-inflammatory states and might contribute to some of the side effects of corticosteroids use.

We determined the effect of chronic androgen suppression on inflammation in women with polycystic ovary syndrome (PCOS) compared to weight-matched controls. We performed a pilot project using samples from previous prospective, controlled studies. Nine women with PCOS (5 obese, 4 lean) and 9 ovulatory controls (5 obese, 4 lean) participated in the study. Androgens, C-reactive protein (CRP), interleukin-6 (IL-6), free fatty acids (FFA) and body weight were measured before and after 3 and 6 months of gonadotropin-releasing hormone (GnRH) agonist administration. GnRH agonist treatment decreased estradiol, testosterone and androstenedione to similar levels in all subjects. CRP and IL-6 increased in obese women with PCOS, was unaltered in lean women with PCOS and obese controls, and decreased in lean controls after 6 months of treatment. FFA decreased and body weight increased in obese women with PCOS, but did not change significantly in lean women with PCOS and in either control group after 6 months of treatment. The testosterone reduction was related to increases in weight and IL-6. The fall in FFA was related to the rise in CRP. The increases in weight and IL-6 were related to the rise in CRP. We propose that hyperandrogenism in PCOS may exert an anti-inflammatory effect when obesity is present, but may not promote inflammation in the disorder; and that circulating androgens have a pleiotropic effect on inflammation depending on the combination of PCOS and weight status in a given individual.

Our objective was to determine whether peripheral blood mononuclear cells express amyloid precursor protein (APP) and other mediators involved in the pathogenesis of Alzheimer's disease and whether their expression is suppressed by insulin.Ten obese type 2 diabetic patients were infused with insulin (2 U/h with 100 ml 5% dextrose/h) for 4 h. Patients were also infused with 5% dextrose/h or normal physiological saline for 4 h, respectively, on two other days as controls. Blood samples were obtained at 0, 2, 4, and 6 h.Insulin infusion significantly suppressed the expression of APP, presenilin-1, presenilin-2, and glycogen synthase kinase-3β in peripheral blood mononuclear cells. Dextrose and saline infusions did not alter these indices. Insulin infusion also caused significant parallel reductions in nuclear factor-κB binding activity and plasma concentrations of serum amyloid A and intercellular adhesion molecule-1.A low dose infusion of insulin suppresses APP, presenilin-1, presenilin-2, and glycogen synthase kinase-3β, key proteins involved in the pathogenesis of Alzheimer's disease, in parallel with exerting its other antiinflammatory effects.

Background: High-fat, high-carbohydrate (HFHC) meals are known to induce oxidative and inflammatory stress, an increase in plasma endotoxin concentrations, and an increase in the expression of suppressor of cytokine signaling-3 (SOCS-3). Hypothesis: The intake of a nutritional supplement containing resveratrol and muscadine grape polyphenols reduces HFHC meal-induced oxidative and inflammatory stress and stimulates the activity of the antioxidant transcription factor, Nrf-2, and its downstream targets. Methods: Ten normal, healthy subjects were given a 930-kcal HFHC meal either with placebo or with the supplement. Indices of oxidative stress, inflammation, Nrf-2 binding activity, the concentrations of endotoxin (lipopolysaccharide) and lipoprotein binding protein (LBP), and the expression of TLR-4, CD14, IL-1β, TNFα, SOCS-3, Keap-1, NQO-1, and GST-P1 were measured. Results: The intake of the supplement suppressed the meal-induced elevations of plasma endotoxin and LBP concentrations, the expression of p47phox, TLR-4, CD14, SOCS-3, IL-1β, and Keap-1, while enhancing Nrf-2 binding activity and the expression of NQO-1 and GST-P1 genes. Conclusion: A supplement containing resveratrol and muscadine polyphenols reduces the magnitude of oxidative stress, increase in lipopolysaccharide and LBP and TLR-4, CD14, IL-1β and SOCS-3 expression after an HFHC meal. It also stimulates specific Nrf-2 activity and induces the expression of the related antioxidant genes, NQO-1 and GST-P1. These results demonstrate the acute antioxidant and antiinflammatory effects of resveratrol and polyphenolic compounds in humans in the postprandial state.

OBJECTIVEIn view of the previously described anti-inflammatory effects of insulin, we investigated the potential suppressive effect of insulin on plasma concentrations and expression of the chemokines, monocyte chemoattractant protein-1 (MCP-1) and regulated on activation normal T-cell expressed and secreted (RANTES) and their receptors, chemokine receptor (CCR)-2 and CCR-5, in mononuclear cells (MNCs). We also investigated the effect of insulin on other chemokines.RESEARCH DESIGN AND METHODSTen obese type 2 diabetic patients were infused with insulin (2 units/h with 100 ml of 5% dextrose/h) for 4 h. Another 8 and 6 type 2 diabetic patients were infused with 100 ml of 5% dextrose/h or saline for 4 h, respectively, and served as control subjects. Blood samples were obtained at 0, 2, 4, and 6 h.RESULTSInsulin infusion significantly suppressed the plasma concentrations of MCP-1, eotaxin, and RANTES and the expression of RANTES, macrophage inflammatory protein (MIP)-1β, CCR-2, and CCR-5 in MNCs at 2 and 4 h. Dextrose and saline infusions did not alter these indexes.CONCLUSIONSA low-dose infusion of insulin suppresses the plasma concentration of key chemokines, MCP-1, and RANTES, and the expression of their respective receptors, CCR-2 and CCR-5, in MNCs. Insulin also suppresses the expression of RANTES and MIP-1β in MNCs. These actions probably contribute to the comprehensive anti-inflammatory effect of insulin.

OBJECTIVE We have recently shown that a high-fat high-carbohydrate (HFHC) meal induces an increase in plasma concentrations of endotoxin (lipopolysaccharide [LPS]) and the expression of Toll-like receptor-4 (TLR-4) and suppresser of cytokine signaling-3 (SOCS3) in mononuclear cells (MNCs) in addition to oxidative stress and cellular inflammation. Saturated fat and carbohydrates, components of the HFHC meal, known to induce oxidative stress and inflammation, also induce an increase in LPS, TLR-4, and SOCS3. RESEARCH DESIGN AND METHODS Fasting normal subjects were given 300-calorie drinks of either glucose, saturated fat as cream, orange juice, or only water to ingest. Blood samples were obtained at 0, 1, 3, and 5 h for analysis. RESULTS Indexes of inflammation including nuclear factor-κB (NF-κB) binding, and the expression of SOCS3, tumor necrosis factor-α (TNF-α), and interleukin (IL)-1β in MNCs, increased significantly after glucose and cream intake, but TLR-4 expression and plasma LPS concentrations increased only after cream intake. The intake of orange juice or water did not induce any change in any of the indexes measured. CONCLUSIONS Although both glucose and cream induce NF-κB binding and an increase in the expression of SOCS3, TNF-α, and IL-1β in MNCs, only cream caused an increase in LPS concentration and TLR-4 expression. Equicaloric amounts of orange juice or water did not induce a change in any of these indexes. These changes are relevant to the pathogenesis of atherosclerosis and insulin resistance.

Background: Because obesity is associated with chronic oxidative and inflammatory stress, and high-fat, high-carbohydrate meals induce significant oxidative and inflammatory stress in normal subjects, we have now hypothesized that the intake of a high-fat, high-carbohydrate meal would result in a greater and more prolonged oxidative and inflammatory stress in the obese than in normal subjects. Methods: Ten normal-weight and eight obese subjects were given a high-fat, high-carbohydrate meal after an overnight fast. Blood samples were collected at baseline and hourly following the meal for 3 h. Results: Reactive oxygen species generation by mononuclear cells increased significantly by 2 h in both groups but continued to increase significantly at 3 h in the obese subjects, whereas in normal subjects it returned to baseline. Levels of p47phox increased significantly (by 81 ± 26%) at 3 h in obese individuals (P < 0.05), whereas there was no significant change in p47phox in normal subjects. Nuclear factor-κB DNA binding in mononuclear cells increased significantly (by 48 ± 58%, P < 0.036) at 2 h but not at 3 h in normal subjects, whereas in the obese, nuclear factor-κB increased significantly at both 2 and 3 h (by 36 ± 57 and 42 ± 63%, respectively, P < 0.004). Matrix metalloproteinase-9 concentrations were significantly higher in the obese at baseline (580 ± 103.9 vs. 373 ± 30.03 ng/ml, P < 0.05) and increased to significantly greater concentrations after the meal than in the lean subjects. Conclusions: High-fat, high-carbohydrate meals induced a significantly more prolonged and greater oxidative and inflammatory stress in the obese. This may contribute to the increased atherogenic risk in obesity.

OBJECTIVE—We have previously shown that 300 kcal from glucose intake induces a significant increase in reactive oxygen species (ROS) generation and nuclear factor-κB (NF-κB) binding in the circulating mononuclear cells in healthy normal subjects. We hypothesized that the intake of 300 calories as orange juice or fructose, the other major carbohydrate in orange juice, would induce a significantly smaller response than that of glucose. RESEARCH DESIGN AND METHODS— Four groups (eight subjects each) of normal-weight subjects were given a 300-cal drink of glucose (75 g), fructose (75 g), or orange juice or water sweetened with saccharin (control group) to drink, and then blood samples were collected. RESULTS—There was a significant increase in ROS generation by mononuclear cells (by 130 ± 18%, P < 0.001), polymorph nuclear cells (by 95 ± 22%, P < 0.01), and in NF-κB binding in mononuclear cells by 82 ± 16% (P < 0.01) over the baseline after 2 h of glucose intake. These changes were absent following fructose, orange juice, or water intake. There was significantly lower ROS generation and NF-κB binding following orange juice, fructose, and water compared with glucose (P < 0.001 for all). Furthermore, incubation of mononuclear cells in vitro with 50 mmol/l of the flavonoids hesperetin or naringenin reduced ROS generation by 52 ± 7% and 77 ± 8% (P < 0.01), respectively, while fructose or ascorbic acid did not cause any change. CONCLUSIONS—Caloric intake in the form of orange juice or fructose does not induce either oxidative or inflammatory stress, possibly due to its flavonoids content and might, therefore, represent a potentially safe energy source.

Hyperandrogenism and inflammation are related in polycystic ovary syndrome (PCOS). Hyperandrogenemia can induce inflammation in reproductive-age women, but the mechanism for this phenomenon is unclear.We examined the in vivo and in vitro effects of hyperandrogenism on mononuclear cell (MNC)-derived androgen receptor (AR) status and TNFα release.This study combined a randomized, controlled, double-blind protocol with laboratory-based cell culture experiments.This work was performed in an academic medical center.Lean, healthy, reproductive-age women were treated with 130 mg of dehydroepiandrosterone (DHEA) or placebo (n = 8 subjects each) for 5 days and also provided untreated fasting blood samples (n = 12 subjects) for cell culture experiments.AR mRNA content and TNFα release were measured before and after DHEA administration in the fasting state and 2 hours after glucose ingestion. TNFα release in the fasting state was also measured in cultured MNCs exposed to androgens with or without flutamide preincubation.At baseline, subjects receiving DHEA or placebo exhibited no significant difference in androgens and TNFα release from MNCs before and after glucose ingestion. Compared with placebo, DHEA administration raised levels of T, androstenedione, and DHEA sulfate, and increased MNC-derived AR mRNA content and TNFα release in the fasting state and in response to glucose ingestion. Compared with MNC exposure to baseline concentrations of DHEA (175 ng/dL) or T (50 ng/dL), the absolute change in TNFα release increased after exposure to T concentrations of 125 and 250 ng/dL and a DHEA concentration of 1750 ng/dL. Preincubation with flutamide reduced the TNFα response by ≥ 60% across all T concentrations.Androgen excess in vivo and in vitro comparable to what is present in PCOS increases TNFα release from MNCs of lean healthy reproductive-age women in a receptor-dependent fashion. Hyperandrogenemia activates and sensitizes MNCs to glucose in this population.

Oxidative stress induced by reactive oxygen species (ROS) is involved in the development of pancreatic β-cell dysfunction.We determined the relationship between mononuclear cell (MNC)-derived ROS generation and p47phox protein content in response to glucose ingestion and β-cell function in women with polycystic ovary syndrome (PCOS).This was a cross-sectional study.This study was conducted at an academic medical center.Twenty-nine normoglycemic women with PCOS (13 lean, 16 obese) and 25 ovulatory controls (16 lean, 9 obese) underwent a 3-h 75-g oral glucose tolerance test (OGTT).Pancreatic β-cell function was calculated as glucose-stimulated insulin secretion (insulin/glucose area under the curve0-30 min; GSIS)×Matsuda index-derived insulin sensitivity (ISOGTT). ROS generation was measured by chemiluminescence, and p47phox protein was quantified by Western blotting in MNC isolated from blood samples obtained at 0 and 2 hours of the OGTT.Compared with controls, women with PCOS exhibited a higher percent change from baseline in ROS generation and p47phox protein in conjunction with greater GSIS and a tendency toward lower β-cell function. Lean women with PCOS exhibited a greater percent change from baseline in ROS generation and p47phox protein yet had similar GSIS responses compared with lean controls despite having lower ISOGTT. For the combined groups, β-cell function was inversely related to ROS generation and p47phox protein. GSIS was directly related to body mass index, central obesity, and circulating androgens.In normoglycemic women, obesity plays a role in exaggerating GSIS. However, MNC-derived oxidative stress is independent of obesity and may contribute to the decline in β-cell function in women with PCOS.

The purpose of this study was to determine whether an insulin infusion exerts an anti-inflammatory effect and whether the infusion of small amounts of glucose results in oxidative and inflammatory stress in patients with type 1 diabetes. Ten patients with type 1 diabetes were infused with either 2 U/h of insulin with 100 ml 5% dextrose/h to or just dextrose (100 ml/h) or physiological saline (100 ml/h) for 4 h after an overnight fast on three separate days. Blood samples were collected at 0, 2, 4, and 6 h. Insulin with glucose infusion led to the maintenance of euglycemia and a significant suppression of reactive oxygen species (ROS) generation, p47phox expression, Toll-like receptor (TLR)-4, TLR-2, TLR-1, CD14, high-mobility group-B1 (HMGB1), p38 mitogen-activated protein (MAP) kinase, c-Jun NH2-terminal kinase (JNK)-1, and platelet/endothelial cell adhesion molecule expression and a fall in serum concentrations of C-reactive protein, HMGB1, and rapid upon activation T cell expressed and secreted. Glucose infusion led to an increase in plasma glucose concentration from 115 (fasting) to 215 (at 4 and 6 h) mg/dl and to an increase in ROS generation, the expression of TLR-4, TLR-2, TLR-1, HMGB1, p38 MAP kinase, and JNK-1, and plasma concentrations of HMGB1. While insulin reduces indexes of oxidative and inflammatory stress in patients with type 1 diabetes, even small amounts of glucose (20 g over 4 h) induce oxidative and inflammatory stress. These effects are reflected in TLR, p38 MAP kinase, and HMGB1 expression. The induction of significant oxidative and inflammatory stress by small amounts of glucose in patients with type 1 diabetes may have important pathophysiological and therapeutic implications.

Study question What is the effect of glucose ingestion on leukocytic reactive oxygen species (ROS) generation in normal-weight women with polycystic ovary syndrome (PCOS) with and without excess abdominal adiposity (AA)? Summary answer Normal-weight women with PCOS exhibit an increase in leukocytic ROS generation in response to glucose ingestion, and this increase is independent of excess AA. What is known already Excess adipose tissue is a source of oxidative stress. Normal-weight women with PCOS exhibit oxidative stress and can have excess AA. Study design and size This is a cross-sectional study involving 30 reproductive-age women. Participants/materials, setting and methods Fourteen normal-weight women with PCOS (6 normal AA, 8 excess AA) and 16 body composition-matched controls (8 normal AA, 8 excess AA) underwent body composition assessment by dual-energy absorptiometry and an oral glucose tolerance test (OGTT) at a university medical center. Insulin sensitivity was derived from the OGTT (IS(OGTT)). Blood was drawn while fasting and 2 h after glucose ingestion to measure leukocytic ROS generation and p47(phox) protein content and plasma thiobarbituric acid-reactive substances (TBARS) and C-reactive protein (CRP). Main results and the role of chance Compared with controls, both PCOS groups exhibited lower IS(OGTT) (43-54%) and greater percentage change (% change) in ROS generation (96-140%), p47(phox) protein (18-28%) and TBARS (17-48%). Compared with women with PCOS with excess AA, those with normal AA exhibited higher testosterone levels (29%) and lower CRP levels (70%). For the combined groups, IS(OGTT) was negatively correlated with the % change in ROS generation and p47(phox) protein. CRP was positively correlated with abdominal fat. The % change in p47(phox) protein was positively correlated with CRP and androgens. Limitations, reasons for caution Although this study is adequately powered to assess differences in ROS generation between the women with PCOS and control participants, the modest sample size merits caution when interpreting the corroborative results of the additional measures of oxidative stress and inflammation. Wider implications of the findings This study highlights the unique pro-oxidant contribution of circulating leukocytes in the development of insulin resistance and hyperandrogenism in PCOS. Study funding/competing interest(s) Supported by NIH grant HD-048535 to F.G. The authors have nothing to disclose.

Inflammation and excess abdominal adiposity (AA) are often present in normal-weight women with polycystic ovary syndrome (PCOS).We determined the effects of hyperglycemia on nuclear factor-κB (NFκB) activation in mononuclear cells (MNC) of normal-weight women with PCOS with and without excess AA.This was a prospective controlled study.The study was conducted at an academic medical center.Fifteen normal-weight, reproductive-age women with PCOS (seven normal AA, eight excess AA) and 16 body composition-matched controls (eight normal AA, eight excess AA) participated in the study.Body composition was measured by dual-energy absorptiometry. Insulin sensitivity was derived from an oral glucose tolerance test (IS(OGTT)). Activated NFκB and the protein content of p65 and inhibitory-κB were quantified from MNC, and TNFα and C-reactive protein (CRP) were measured in plasma obtained from blood drawn while fasting and 2 h after glucose ingestion.Compared with controls, both PCOS groups exhibited lower IS(OGTT), increases in activated NFκB and p65 protein, and decreases in inhibitory-κB protein. Compared with women with PCOS with excess AA, those with normal AA exhibited higher testosterone levels and lower TNFα and CRP levels. For the combined groups, the percent change in NFκB activation was negatively correlated with IS(OGTT) and positively correlated with androgens. TNFα and CRP were positively correlated with abdominal fat.In normal-weight women with PCOS, the inflammatory response to glucose ingestion is independent of excess AA. Circulating MNC and excess AA are separate and unique sources of inflammation in this population.

Obesity and type 2 diabetes are associated with an increase in the incidence and prevalence of Alzheimer's disease (AD) and an impaired cognitive function. Because peripheral blood mononuclear cells (MNC) express amyloid precursor protein (APP), the precursor of β-amyloid, which forms the pathognomonic plaques in the brain, we hypothesized that APP expression diminishes after the marked caloric restriction and weight loss associated with Roux-en-Y gastric bypass (RYGB) surgery.Fifteen type 2 diabetic patients with morbid obesity (body mass index, 52.1 ± 13 kg/m(2)) underwent RYGB, and the expression of inflammatory and AD-related genes was examined before and after 6 months in plasma and in MNC.Body mass index fell to 40.4 ± 11.1 kg/m(2) at 6 months after RYGB. There was a significant fall in plasma concentrations of glucose and insulin and in homeostasis model of assessment for insulin resistance. The expression of APP mRNA fell by 31 ± 9%, and that of protein fell by 36 ± 14%. In addition, there was a reduction in the expression of other AD-related genes including presinilin-2, ADAM-9, GSK-3β, PICALM, SORL-1, and clusterin (P0.05 for all). Additionally, the expression of c-Fos, a subunit of the proinflammatory transcription factor AP-1, was also suppressed after RYGB. These changes occurred in parallel with reductions in other proinflammatory mediators including C-reactive protein and monocyte chemoattractant protein-1.Thus, the reversal of the proinflammatory state of obesity is associated with a concomitant reduction in the expression of APP and other AD-related genes in MNC. We conclude that obesity and caloric intake modulate the expression of APP in MNC. If indeed, this effect also occurs in the brain, this may have implications for the pathogenesis and the treatment of AD. It is relevant that cognitive function has been shown to improve with weight loss following bariatric surgery.

Our objective was to determine whether exenatide exerts an antiinflammatory effect.Twenty-four patients were prospectively randomized to be injected sc with either exenatide 10 μg twice daily [n = 12; mean age = 56 ± 3 yr; mean body mass index = 39.8 ± 2 kg/m(2); mean glycosylated hemoglobin (HbA1c) = 8.6 ± 0.4%] or placebo twice daily (n = 12; mean age = 54 ± 4 yr; mean body mass index = 39.1 ± 1.6 kg/m(2); mean HbA1c = 8.5 ± 0.3%) for 12 wk. Fasting blood samples were obtained at 0, 3, 6, and 12 wk. Blood samples were also collected for up to 6 h after a single dose of exenatide (5 μg) or placebo.Fasting blood glucose fell from 139 ± 17 to 110 ± 9 mg/dl, HbA1c from 8.6 ± 0.4 to 7.4 ± 0.5% (P0.05), and free fatty acids by 21 ± 5% from baseline (P0.05) with exenatide. There was no weight loss. There was a significant reduction in reactive oxygen species generation and nuclear factor-κB binding by 22 ± 9 and 26 ± 7%, respectively, and the mRNA expression of TNFα, IL-1β, JNK-1, TLR-2, TLR-4, and SOCS-3 in mononuclear cells by 31 ± 12, 22 ± 10, 20 ± 11, 22 ± 9, 16 ± 7, and 31 ± 10%, respectively (P0.05 for all) after 12 wk of exenatide. After a single injection of exenatide, there was a reduction by 20 ± 7% in free fatty acids, 19 ± 7% in reactive oxygen species generation, 39 ± 11% in nuclear factor-κB binding, 18 ± 9% in TNFα expression, 26 ± 7% in IL-1β expression, 18 ± 7% in JNK-1 expression, 24 ± 12% in TLR-4 expression, and 23 ± 11% in SOCS-3 expression (P0.05 for all). The plasma concentrations of monocyte chemoattractant protein-1, matrix metalloproteinase-9, serum amyloid A, and IL-6 were suppressed after 12 wk exenatide treatment by 15 ± 7, 20 ± 11, 16 ± 7, and 22 ± 12%, respectively (P0.05 for all).Exenatide exerts a rapid antiinflammatory effect at the cellular and molecular level. This may contribute to a potentially beneficial antiatherogenic effect. This effect was independent of weight loss.

Background Roux-en-Y gastric bypass (RYGB) results in profound weight loss and resolution of type 2 diabetes mellitus (T2DM). The mechanism of this remarkable transition remains poorly defined. It has been proposed that endotoxin (lipopolysaccharide [LPS]) sets inflammatory tone, triggers weight gain, and initiates T2DM. Because RYGB may diminish LPS from endogenous and exogenous sources, we hypothesized that LPS and the associated cascade of oxidative and inflammatory stress would diminish after RYGB. Methods Fifteen adults with morbid obesity and T2DM undergoing RYGB were studied. After an overnight fast, a baseline blood sample was collected the morning of surgery and at 180 days to assess changes in glycemia, insulin resistance, LPS, mononuclear cell nuclear factor (NF)-κB binding and mRNA expression of CD14, TLR-2, TLR-4, and markers of inflammatory stress. Results At 180 days after RYGB, subjects had a significant decrease in body mass index (52.1 ± 13.0 to 40.4 ± 11.1), plasma glucose (148 ± 8 to 101 ± 4 mg/dL), insulin (18.5 ± 2.2 mμU/mL to 8.6 ± 1.0 mμU/mL) and HOMA-IR (7.1 ± 1.1 to 2.1 ± 0.3). Plasma LPS significantly reduced by 20 ± 5% (0.567 ± 0.033 U/mL to 0.443 ± 0.022E U/mL). NF-κB DNA binding decreased significantly by 21 ± 8%, whereas TLR-4, TLR-2, and CD-14 expression decreased significantly by 25 ± 9%, 42 ± 8%, and 27 ± 10%, respectively. Inflammatory mediators CRP, MMP-9, and MCP-1 decreased significantly by 47 ± 7% (10.7 ± 1.6 mg/L to 5.8 ± 1.0 mg/L), 15 ± 6% (492 ± 42 ng/mL to 356 ± 26 ng/mL) and 11 ± 4% (522 ± 35 ng/mL to 466 ± 35 ng/mL), respectively. Conclusion LPS, NF-κB DNA binding, TLR-4, TLR-2, and CD14 expression, CRP, MMP-9, and MCP-1 decreased significantly after RYGB. The mechanism underlying resolution of insulin resistance and T2DM after RYGB may be attributable, at least in part, to the reduction of endotoxemia and associated proinflammatory mediators.

OBJECTIVE To investigate whether insulin reduces the magnitude of oxidative, nitrosative, and inflammatory stress and tissue damage responses induced by endotoxin (lipopolysaccharide [LPS]). RESEARCH DESIGN AND METHODS Nine normal subjects were injected intravenously with 2 ng/kg LPS prepared from Escherichia coli. Ten others were infused with insulin (2 units/h) for 6 h in addition to the LPS injection along with 100 ml/h of 5% dextrose to maintain normoglycemia. RESULTS LPS injection induced a rapid increase in plasma concentrations of nitric oxide metabolites, nitrite and nitrate (NOM), and thiobarbituric acid–reacting substances (TBARS), an increase in reactive oxygen species (ROS) generation by polymorphonuclear leukocytes (PMNLs), and marked increases in plasma free fatty acids, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), macrophage migration inhibition factor (MIF), C-reactive protein, resistin, visfatin, lipopolysaccharide binding protein (LBP), high mobility group-B1 (HMG-B1), and myoglobin concentrations. The coinfusion of insulin led to a total elimination of the increase in NOM, free fatty acids, and TBARS and a significant reduction in ROS generation by PMNLs and plasma MIF, visfatin, and myoglobin concentrations. Insulin did not affect TNF-α, MCP-1, IL-6, LBP, resistin, and HMG-B1 increases induced by the LPS. CONCLUSIONS Insulin reduces significantly several key mediators of oxidative, nitrosative, and inflammatory stress and tissue damage induced by LPS. These effects of insulin require further investigation for its potential use as anti-inflammatory therapy for endotoxemia.

Background: The intake of glucose or a high-fat, high-carbohydrate (HFHC) meal, but not orange juice, induces an increase in inflammation and oxidative stress in circulating mononuclear cells (MNCs) of normal-weight subjects. Objective: We investigated the effect of orange juice on HFHC meal‐induced inflammation and oxidative stress and the expression of plasma endotoxin and Toll-like receptors (TLRs). Design: Three groups (10 subjects in each group) of normal, healthy subjects were asked to drink water or 300 kcal glucose or orange juice in combination with a 900-kcal HFHC meal. Blood samples were obtained before and 1, 3, and 5 h after the drinks and meal combinations were consumed. Results: Protein expression of the NADPH oxidase subunit p47 phox , phosphorylated and total p38 mitogen-activated protein kinase, and suppressor of cytokine signaling-3; TLR2 and TLR4 messenger RNA (mRNA) and protein expression; mRNA expression of matrix metalloproteinase (MMP)-9 in MNCs; and plasma concentrations of endotoxin and MMP-9 increased significantly after glucose or water were consumed with the meal but not when orange juice was consumed with the meal. The generation of reactive oxygen species by polymorphonuclear cells was significantly lower when orange juice was added to the meal than when water or glucose was added to the meal. Conclusions: The combination of glucose or water and the HFHC meal induced oxidative and inflammatory stress and an increase in TLR expression and plasma endotoxin concentrations. In contrast, orange juice intake with the HFHC meal prevented meal-induced oxidative and inflammatory stress, including the increase in endotoxin and TLR expression. These observations may help explain the mechanisms underlying postprandial oxidative stress and inflammation, pathogenesis of insulin resistance, and atherosclerosis. Am J Clin Nutr 2010;91:940‐9.