Plasma adiponectin concentration and tumor necrosis factor-alpha system activity in lean non-diabetic offspring of type 2 diabetic subjects

Association between parental history of diabetes and the incidence of type 2 diabetes mellitus differs according to the sex of the parent and offspring's body weight: A finding from a Japanese worksite-based cohort study

OBJECTIVE

To investigate differences in the association of parental history of diabetes with the risk of type 2 diabetes mellitus (T2DM) in the offspring according to the sex of the parent and the offspring's body weight.

METHODS

A prospective cohort study of 4446 middle-aged non-diabetic Japanese men and women were followed in Aichi Prefecture, central Japan, from 2002 to 2011. Subjects were categorized by their self-reported parental history of diabetes ("no parental history," "father only," "mother only," and "both"). The association of parental history of diabetes and incidence in the offspring was examined according to overweight status adjusted for age, sex, birth weight, smoking, alcohol consumption, physical activity, total energy intake, body mass index, and number of metabolic syndrome components.

RESULTS

During follow-up (median 8.9 years), 277 subjects developed T2DM. Parental history of diabetes was positively associated with T2DM incidence. However, stratified analysis by overweight status revealed that only maternal history was associated with increased T2DM incidence in non-overweight subjects (hazard ratio=2.35, 95% confidence interval: 1.41-3.91). While in overweight subjects, paternal history was significantly associated with higher T2DM incidence (hazard ratio=1.98, 95% confidence interval: 1.19-3.28).

CONCLUSIONS

Our results suggest that parental history of diabetes mellitus is associated with the incidence of T2DM in offspring differently according to the sex of the affected parent and the offspring's body weight.

The normoglycemic first-degree relatives of patients with type 2 diabetes mellitus have low circulating omentin-1 and adiponectin levels

OBJECTIVE

It has been suggested that adipose-derived cytokines act as insulin sensitizers/insulin-mimetics and some others may induce insulin resistance. In order to elucidate the potential role of novel adipocytokines in the pre-diabetes states, circulating levels of novel adipocytokines were evaluated in first-degree relatives of subjects with type 2 diabetes mellitus (FDRs).

METHOD

Serum omentin-1, adiponectin and retinol-binding protein 4 (RBP4) levels were measured in 179 subjects (90 glucose tolerant FDRs and 89 age- and sex-matched healthy controls) using enzyme-linked immunosorbent assay (ELISA) methods.

RESULTS

There was no significant difference between the two groups regarding serum RBP4 concentrations. However, serum omentin-1 (median [interquartile range], 6.18 [4.06-11.52]ng/ml versus 10.50 [4.30-20.60]ng/ml, p=0.004) and adiponectin (mean±SD, 10.07±4.0 μg/ml versus 20.66±8.12 μg/ml, p<0.0001) levels were significantly lower in FDRs when compared with the controls. In multiple logistic regression analysis, FDRs showed a significant association with lower circulating omentin-1 and adiponectin levels, even after adjustments were made for age, sex, body mass index, blood pressure measures, and biochemical parameters including glucose status, lipid profile, insulin levels and HOMA-IR (OR=0.49, CI [0.30-0.79]; p=0.004 and OR=0.74, CI [0.67-0.82]; p<0.0001, respectively). However, FDRs did not show a significant association with serum RBP4 levels in different models of regression analyses.

CONCLUSIONS

The FDRs showed significant associations with lower omentin-1 and adiponectin levels. A potential role for these adipokines in the FDRs' increased risk of diabetes needs to be further elucidated.

Acute effects of dietary fat on inflammatory markers and gene expression in first-degree relatives of type 2 diabetes patients

BACKGROUND

Subjects with type 2 diabetes (T2D) and their relatives (REL) carry an increased risk of cardiovascular disease (CVD). Low-grade inflammation, an independent risk factor for CVD, is modifiable by diet. Subjects with T2D show elevated postprandial inflammatory responses to fat-rich meals, while information on postprandial inflammation in REL is sparse.

AIM

To clarify whether medium-chain saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) have differential acute effects on low-grade inflammation in REL compared to controls (CON).

METHODS

In randomized order, 17 REL and 17 CON ingested two fat-rich meals, with 72 energy percent from MUFA and 79 energy percent from mainly medium-chain SFA, respectively. Plasma high sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), adiponectin, and leptin were measured at baseline, 15 min, 60 min, and 240 min postprandially. Muscle and adipose tissue biopsies were taken at baseline and 210 min after the test meal, and expression of selected genes was analyzed.

RESULTS

Plasma IL-6 increased (p < 0.001) without difference between REL and CON and between the meals, whereas plasma adiponectin and plasma hs-CRP were unchanged during the 240 min observation period. Plasma leptin decreased slightly in response to medium-chain SFA in both groups, and to MUFA in REL. Several genes were differentially regulated in muscle and adipose tissue of REL and CON.

CONCLUSIONS

MUFA and medium-chain SFA elicit similar postprandial circulating inflammatory responses in REL and CON. Medium-chain SFA seems more proinflammatory than MUFA, judged by the gene expression in muscle and adipose tissue of REL and CON.

Relationships between serum adiponectin and soluble TNF-α receptors and glucose and lipid oxidation in lean and obese subjects

Insulin resistance might be associated with an impaired ability of insulin to stimulate glucose oxidation and inhibit lipid oxidation. Insulin action is also inversely associated with TNF-α system and positively related to adiponectin. The aim of the present study was to analyze the associations between serum adiponectin, soluble TNF-α receptors concentrations and the whole-body insulin sensitivity, lipid and glucose oxidation, non-oxidative glucose metabolism (NOGM) and metabolic flexibility in lean and obese subjects. We examined 53 subjects: 25 lean (BMI < 25 kg × m(-2)) and 28 with overweight or obesity (BMI > 25 kg × m(-2)) with normal glucose tolerance. Hyperinsulinemic euglycemic clamp and indirect calorimetry were performed. An increase in respiratory exchange ratio in response to insulin was used as a measure of metabolic flexibility. Obese subjects had lower insulin sensitivity, adiponectin and higher sTNFR1 (all P < 0.001) and sTNFR2 (P = 0.001). Insulin sensitivity was positively related to adiponectin (r = 0.49, P < 0.001) and negatively related to sTNFR1 (r = -0.40, P = 0.004) and sTNFR2 (r = -0.52, P < 0.001). Adiponectin was related to the rate of glucose (r = 0.47, P < 0.001) and lipid (r = -0.40, P = 0.003) oxidation during the clamp, NOGM (r = 0.41, P = 0.002) and metabolic flexibility (r = 0.36, P = 0.007). Serum sTNFR1 and sTNFR2 were associated with the rate of glucose (r = -0.45, P = 0.001; r = -0.51, P < 0.001, respectively) and lipid (r = 0.52, P < 0.001; r = 0.46, P = 0.001, respectively) oxidation during hyperinsulinemia, NOGM (r = -0.31, P = 0.02; r = -0.43, P = 0.002, respectively) and metabolic flexibility (r = -0.47 and r = -0.51, respectively, both P < 0.001) in an opposite manner than adiponectin. Our data suggest that soluble TNF-α receptors and adiponectin have multiple effects on glucose and lipid metabolism in obesity.

Hyperinsulinemia acutely increases serum macrophage inhibitory cytokine-1 concentration in anorexia nervosa and obesity

CONTEXT

Macrophage inhibitory cytokine-1 (MIC-1) plays a role in the regulation of cellular responses to stress signals and inflammation. MIC-1 has also been implicated in mediation of tumour-induced anorexia and weight loss. Increased serum concentrations of MIC-1 were found in patients with anorexia nervosa (AN), obesity and type 2 diabetes.

OBJECTIVE

To estimate serum MIC-1 concentration in women with AN and obese women, its regulation by hyperinsulinemia and relationship with insulin sensitivity.

PATIENTS

We examined 20 women with AN, 28 healthy normal-weight female controls and 28 obese women.

MEASUREMENTS

Serum MIC-1 concentration was measured in the fasting state and after 2-h euglycemic hyperinsulinemic clamp.

RESULTS

At baseline, serum MIC-1 was higher in AN in comparison with other groups (normal-weight, P = 0·018; obese, P = 0·01). Hyperinsulinemia resulted in a significant increase in serum MIC-1 concentration in the entire study population (P < 0·001) and in AN (P < 0·001), normal-weight (P = 0·002) and obese (P < 0·001) groups analysed separately. Postclamp serum MIC-1 was still higher in AN women in comparison with other groups (normal-weight, P = 0·012; obese, P = 0·023). When normal-weight and obese women were analysed together, with the exclusion of AN group, an inverse correlation between insulin sensitivity and the change in serum MIC-1 during the clamp was observed (r = -0·27, P = 0·042).

CONCLUSIONS

Hyperinsulinemia resulted in a significant increase in serum MIC-1 in different states of adiposity. Increased serum MIC-1 in AN women might be an additional factor responsible for weight loss in this group.

Adipocytokines, gut hormones and growth factors in anorexia nervosa

Anorexia nervosa is a complex eating disorder of unknown etiology which affects adolescent girls and young women and leads to chronic malnutrition. Clinical manifestations of prolonged semistarvation include a variety of physical features and psychiatric disorders. The study of different biological factors involved in the pathophysiology of anorexia nervosa is an area of active interest. In this review we have described the role of adipocytokines, neurotrophins, peptides of the gastrointestinal system and growth factors in appetite regulation, energy balance and insulin sensitivity in anorexia nervosa patients.

Effects of diabetes family history and exercise training on the expression of adiponectin and leptin and their receptors

Daughters of diabetes patients have lower insulin sensitivity than women with no diabetes family history, but increase insulin sensitivity to a greater extent with exercise training. This study aimed to determine whether differences in circulating concentrations of adiponectin and leptin, and adipose tissue expression of their genes and receptors played a role. Women offspring of patients with type 2 diabetes mellitus (n = 34; age, 35.6 ± 7.0 years; body mass index, 28.1 ± 5.1 kg/m²) and matched controls with no diabetes family history (n = 36; age, 33.6 ± 6.1 years; body mass index, 27.3 ± 4.7 kg/m²) participated. Blood and abdominal subcutaneous adipose tissue samples were obtained at baseline and after a controlled 7-week endurance-type exercise intervention (sessions were performed at 65%-80% of maximum heart rate). At baseline, no significant differences were observed between groups in circulating leptin or adiponectin concentrations, or expression of their genes or receptors. In response to exercise, plasma leptin decreased more in offspring than controls (-32.2% vs -7.3%, P = .005 for interaction); and the long isoform of the leptin receptor messenger RNA (mRNA) increased significantly only in the offspring (+39.4%, P = .026 vs +7.7%, P = .892). Leptin mRNA decreased similarly in both groups (-24.7% vs -25.0%, P < .05 for both). Furthermore, changes in plasma leptin (r = -0.432, P < .001) and leptin mRNA (r = -0.298, P = .019) correlated significantly with changes in insulin sensitivity. Plasma adiponectin decreased similarly in both groups (-12.1% vs -15.2%, P < .01 for both), but no significant changes were observed in adiponectin-related gene expression. This work shows that exercise training has differing effects on leptin-related variables between women with and without a diabetes family history and suggests that these molecular differences may contribute to the differential effects of exercise training on insulin sensitivity between these 2 groups.

Insulin sensitivity, metabolic flexibility, and serum adiponectin concentration in women with anorexia nervosa

Anorexia nervosa (AN) is an eating disorder resulting in sustained low weight and marked decrease in fat mass. The lack of adipose tissue observed in lipodystrophies is accompanied by insulin resistance. It remains unclear if the same phenomenon would be present in AN. The objective of the study was to estimate insulin sensitivity, oxidative and nonoxidative glucose metabolism in insulin-stimulated conditions, metabolic flexibility, and serum adiponectin concentration in women with AN. We examined 21 women with AN and 24 healthy normal-weight female controls. Euglycemic hyperinsulinemic clamp, indirect calorimetry, and the measurement of serum adiponectin concentration were performed in all the subjects. We did not observe differences in insulin sensitivity, oxidative and nonoxidative glucose metabolism in insulin-stimulated conditions, and metabolic flexibility between AN and control subjects. Serum adiponectin was higher in AN women in comparison with control group (P = .002). Women with AN have normal insulin sensitivity because of the preserved response of glucose oxidation, nonoxidative glucose metabolism in response to insulin, and normal metabolic flexibility. High adiponectin concentration and normal insulin sensitivity in anorectic women suggest that in AN the adipocytes are still capable of functioning at the level that is sufficient to prevent the metabolic consequences.

Serum adiponectin is associated with family history of diabetes independently of obesity and insulin resistance in healthy Korean men and women

BACKGROUND

Adiponectin has been reported as a new risk factor for the development of diabetes. However, it is not clear whether adiponectin levels are associated with family history of diabetes (FHD).

OBJECTIVE

The objective of this study was to measure the independent association of serum adiponectin with FHD in relation to insulin resistance and obesity.

METHODS

In 2006, a cross-sectional study was conducted in which waist circumference (WC), body mass index (BMI), and serum adiponectin were measured in 5919 healthy Korean men and women. Multiple linear regression models were used to assess the association of serum adiponectin levels with FHD. The population was classified into two groups according to median values for each of the following variables: WC, BMI, and homeostasis model assessment of insulin resistance (HOMA-IR).

RESULTS

The positive FHD group had higher HOMA-IR and lower adiponectin levels in both men and women than those without FHD. Adiponectin levels were significantly associated with FHD in men and women respectively, after adjusting for age, BMI, and alcohol consumption (P=0.0123 and 0.0004). The relationship between adiponectin and FHD was similar between the high and low insulin resistance, BMI, and WC groups in male non-smokers and in all Korean women.

CONCLUSION

These results confirm that adiponectin levels are associated with FHD. These data also suggest that the association of serum adiponectin with FHD may be independent of obesity and insulin resistance.

Adiponectin and its response to thiazolidinediones are associated with insulin-mediated glucose metabolism in type 2 diabetic patients and their first-degree relatives

Patients with type 2 diabetes (T2D) and their first-degree relatives (FDRs) are characterized by hypoadiponectinaema and insulin resistance. In T2D patients, plasma adiponectin and insulin sensitivity (SI) increase in response to thiazolidinediones (TZDs). These findings suggest a role for adiponectin in the regulation of SI. We studied the relationship between plasma adiponectin and glucose and lipid metabolism and the effect of troglitazone (200 mg/day) for 12 weeks in 19 normoglycaemic, obese FDR and 20 obese T2D patients, using euglycaemic-hyperinsulinaemic clamps, glycolytic flux calculations and indirect calorimetry. Plasma adiponectin was similar in both groups, despite higher glucose disposal (Rd), glucose oxidation and glycolytic flux and lower lipid oxidation during insulin stimulation in FDR compared with T2D patients. Plasma adiponectin correlated with insulin-stimulated Rd, non-oxidative glucose disposal (NOGD), glucose storage and SI in both groups after adjustment for sex and body fat. The troglitazone-mediated upregulation of plasma adiponectin was associated with increased insulin-stimulated Rd, NOGD and glucose storage in both groups. No effect on endogenous glucose production was observed. In FDR, plasma adiponectin correlated with insulin-stimulated glycogen synthase activity and the troglitazone-induced increase in plasma adiponectin correlated with the improvement in insulin-stimulated Rd and SI after adjustment for sex and body fat. In conclusion, plasma adiponectin in weight-matched FDR and T2D patients is comparably low and correlates with insulin-mediated glucose uptake and storage. Moreover, these data provide evidence for an adiponectin-dependent insulin-sensitizing effect of TZDs at an early stage before development of T2D and that this effect is exerted mainly on insulin-mediated glucose metabolism.

Combined association of maternal and paternal family history of diabetes with plasma leptin and adiponectin in overweight Hispanic children

AIMS

To investigate the importance of a maternal and paternal family history of Type 2 diabetes and their combined association with plasma leptin and adiponectin levels in overweight Latino children with a family history of Type 2 diabetes (T2DM).

METHODS

This cross-sectional study investigated the combined association of a maternal and paternal family history of T2DM with leptin and adiponectin in 175 overweight Latino children (age 11.1 +/- 1.7 years). All subjects had a family history of T2DM. Plasma adiponectin and leptin levels, body fat measured by dual-energy X-ray absorptiometry, Tanner stage, age and insulin sensitivity were assessed.

RESULTS

After adjustment for age, gestational diabetes, insulin sensitivity and body fat, a combined maternal and paternal family history of T2DM was associated with higher leptin concentrations (P = 0.004) compared with a maternal or paternal family history alone. This association was most pronounced at Tanner stage 1 (P for interaction family history x tanner stage = 0.022). The presence of a combined maternal and paternal family history of T2DM accounted for 4% (P = 0.003) of the variation in leptin concentrations. No such combined association was observed for adiponectin levels.

CONCLUSIONS

Maternal and paternal family history of T2DM may have an additive impact on leptin, but not on adiponectin levels independent of adiposity and insulin sensitivity in overweight Latino children. This may contribute to a further clinically relevant deterioration of metabolic health in this population.

Plasma levels of soluble tumor necrosis factor-alpha receptors are related to total and LDL-cholesterol in lean, but not in obese subjects

Background

Tumor necrosis factor-α (TNFα) is a mediator of insulin resistance. Plasma levels of soluble TNFα receptors (sTNFR1 and sTNFR2) probably reflect paracrine action of the cytokine. TNFα is also a regulator of lipid metabolism, however, data about impact of obesity on the relationships between TNFα and plasma lipids remain controversial.

Aim

The purpose of the present study was to examine the associations of TNFα system with plasma lipids in lean and obese subjects with normal glucose metabolism.

Methods

We examined 63 subjects, 33 lean (BMI<25 kg × m^-2) and 30 with marked overweight or obesity (BMI>27.8 kg × m^-2). Anthropometric and biochemical parameters were measured. Oral glucose tolerance test and euglycemic hyperinsulinemic clamp were also performed.

Results

Obese subjects were markedly more insulin resistant and had higher levels of both TNFα receptors. Total (TC) and LDL-cholesterol (LDL-C), triglycerides (TG) and non-esterified fatty acids (NEFA) were also higher in the obese group. In obese subjects, both receptors were significantly related to TG and HDL-cholesterol (HDL-C), while sTNFR2 was also associated with NEFA. All those correlations disappeared after controlling for insulin sensitivity. In lean subjects, both receptors were related to TC, HDL-C and LDL-C. In that group, sTNFR1 predicted values of all those parameters independently of BMI, plasma glucose and insulin, and insulin sensitivity.

Conclusion

We conclude that TNFα receptors are associated with plasma lipids in different way in lean and in obese subjects. TNFα system is probably important in determining cholesterol levels in lean subjects, while in obese this effect might be masked by other metabolic abnormalities.

Increased serum interleukin-18 concentration is associated with hypoadiponectinemia in obesity, independently of insulin resistance

OBJECTIVE

Interleukin-18 (IL-18) is a cytokine with proinflammatory and proatherogenic properties, which might be associated with the development of insulin resistance. In contrast, adiponectin, a protein secreted by adipose tissue, might exert insulin-sensitizing and antiatherogenic effects. The aim of the present study was to analyze the association between serum IL-18 and adiponectin in lean and obese subjects, in relation to insulin resistance.

DESIGN

Cross-sectional study.

SUBJECTS

One hundred and thirty individuals, 62 lean (body mass index (BMI)<25 kg/m(2), 30 men and 32 women) and 68 with overweight or obesity (BMI>25 kg/m(2), 24 men and 44 women), with normal glucose tolerance and without concomitant diseases.

MEASUREMENTS

Oral glucose tolerance test, euglycemic hyperinsulinemic clamp, serum concentrations of IL-18, IL-6, soluble tumor necrosis factor-alpha receptors and adiponectin.

RESULTS

Obese subjects had lower insulin sensitivity (M value, P=0.00029) and serum adiponectin (P=0.01) and higher levels of serum IL-18 (P=0.00055). Circulating IL-18 was negatively related to adiponectin (r=-0.31, P=0.00027) and insulin sensitivity (r=-0.33, P=0.00012). Subgroup analysis revealed that these associations were present in the obese (adiponectin, r=-0.38, P=0.0014; M, r=-0.29, P=0.016), but not in lean individuals (r=-0.17, P=0.18 and r=-0.20, P=0.12, respectively). Association of IL-18 with adiponectin remained significant after adjustment for other estimated parameters, including insulin sensitivity. Also, relationship between IL-18 and insulin sensitivity was independent of other estimated parameters.

CONCLUSION

Serum IL-18 is inversely related to serum adiponectin, independently of insulin resistance. The relationships of IL-18 with adiponectin and insulin sensitivity are influenced by the presence of overweight/obesity.