Disassociated relation between plasma tumor necrosis factor-α, interleukin-6 and increased body weight in Amerindian women: A long-term prospective study of natural body weight variation and impaired glucose tolerance

<p>Abstract</p> <p>Background</p> <p>Inflammatory cytokines are linked to obesity-related insulin resistance and may predict type 2 diabetes independently of obesity. We previously reported that a majority of a cohort of 73 non-diabetic women with normal plasma (p-)glucose with Amerindian heritage in Lima, Peru, during a 5-year period increased both body weight and p-glucose levels, yet p-insulin was unaltered. A high proportion of palmitoleic acid (16:1n-7) in serum (s) and systolic blood pressure (SBP) were independent predictors of high p-glucose. Whether cytokines also contributed is, however, not known.</p> <p>Methods</p> <p>During 5 years we prospectively investigated the relation between changed concentrations of p-tumor necrosis factor (TNF)-α, p-interleukin (IL)-6 and circulating insulin and glucose in relation to the natural variation of body weight. Study variables included anthropometric measurements, p-insulin, TNF-α, IL-6, SBP and the proportion of 16:1n-7 in s-fatty acid composition.</p> <p>Results</p> <p>Weight and waist differences correlated negatively to the difference in p-TNF-α but positively to differences in p-IL-6 and p-insulin, whereas the increase of p-glucose from baseline to follow-up did not correlate with changes in levels of the two cytokines. In multiple regression analysis changes of TNF-α and insulin contributed independently to the variance in weight. P-insulin at baseline and weight change were determinants of fasting p-insulin at follow-up. Multiple regression analysis revealed that weight change (t-value = - 2.42; P = 0.018) and waist change (t-value = 2.41; P = 0.019) together with S-16:1n-7 (p < 0.0001) and SBP (p = 0.0005) at baseline were significant predictors of p-glucose at follow-up.</p> <p>Conclusion</p> <p>Our prospective study of Amerindian women revealed disassociations between changes in p-TNF-α and p-IL-6 in relation to variation in body weight. A high proportion of s-16:1n-7, SBP at baseline together with weight and waist changes were independent predictors of p-glucose at follow-up. The exact role of the opposite effects and clinical impact of p-TNF-α and p-IL-6 on loss and gain of body weight and indirectly on the development of glucose intolerance is not known.</p

Improved metabolic risk markers following two 6-month physical activity programs among socioeconomic marginalized women of native American ancestry in Lima, Peru

It is known that ethnicity is a risk factor for diabetes. Thus, individuals of African, Latin American, and Asian descent are particularly susceptible (1). As an example, a health survey in six urban areas in Peru found a diabetes prevalence of 17% among women (2,3). It was also found that low socioeconomic status was associated with a high burden of noncommunicable diseases and appeared as an independent risk factor for diabetes. In several populations, it is known that increased physical activity reduces the risk for diabetes (4,5). Whether this applies for all populations is, however, not known. The aim of the present study was to explore if supervised endurance training is feasible among socioeconomically marginalized women of a poor urban area in Lima, Peru

Positive correlation between tumor necrosis factor (TNF)-alpha and cardiorespiratory fitness after six-months of regular aerobic exercise in Peruvian Amerindian women

Background: Adipose tissue is a source of inflammatory cytokines which may influence insulin action. Aim: To evaluate exercise effects on plasma (p)-levels of tumor necrosis factor (TNF)-alpha, and interleukin (IL)-6 in Peruvian Amerindian women. Material and Methods: After five years of observation during which p-glucose deteriorated and weight increased, 44 Peruvian Amerindian women aged 20-59 years took part in a 6-month exercise program. Plasma TNF-alpha and IL-6 had been measured 5 years earlier, and were reassessed before and after exercise, using ELISA kits. Cardiorespiratory fitness was derived from the results of the twelve minutes' walk and expressed as maximum oxygen uptake (VO2max). Results: After the training program, estimated VO2max increased from 18.55 +/- 3.79 to 20.91 +/- 4.61 mL kg(-1) min(-1) (p < 0.01) and p-TNF-alpha increased from 3.2 +/- 3.4 to 4.3 +/- 6.6 pg/mL (p = 0.03). There were reductions in p-glucose from 5.19 +/- 1.59 to 4.32 +/- 1.62 mmol/L (p <0.01) and in waist circumference (p=0.01). Weight, p-insulin, and IL-6 did not change. Levels of p-glucose and p-TNF-alpha observed after the training period were identical to values 5 years earlier. P-TNF-alpha was positively associated with estimated VO2max, prior to (r = .414, p < 0.01) as well as after (r = .362, p < 0.05) exercise, independently of adiposity P-IL-6 was associated with waist circumference but not with estimated VO2max. Conclusions: P-TNF-alpha correlated with estimated VO2max independently of adiposity. Beneficial effects of exercise on p-glucose were observed in spite of an increase in p-TNF-alpha. (Rev Med Chile 2011; 139: 998-1005)

Decreasing levels of tumour necrosis factor alpha and interleukin 6 during lowering of body mass index with orlistat or placebo in obese subjects with cardiovascular risk factors.

Aim: Obesity is associated with increased levels of inflammatory mediators. The objective of this study was to evaluate changes in the leucocyte derived inflammatory mediators tumour necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6) and the isoprostane 8-epi-prostaglandin (PG) F2alpha during BMI lowering with orlistat (Xenical®, Roche) or placebo. Methods: TNF-alpha, IL-6, and 8-epi PGF2alpha evaluated in 376 subjects aged 18-75 years with BMI 28-38 kg/m2 before and after 1 year of double-blind, randomized treatment with orlistat 120 mg or placebo three times daily. Results: Weight reduction was associated with decreasing (p < 0.001) levels of TNF-alpha and IL-6 in both orlistat and placebo groups. After 12 months, TNF-alpha was lower (p < 0.05) in the orlistat compared with the placebo group. In the orlistat group, the change in TNF-alpha correlated with change in s-glucose (r = 0.22; p = 0.01), and the change in 8-epi-PGF2alpha correlated with changes in s-cholesterol (r = 0.27; p < 0.001) and s-LDL-cholesterol (r = 0.28; p < 0.001). Conclusion: Weight reduction was associated with decreasing levels of both TNF-alpha and IL-6. After 12 months of treatment, TNF-alpha levels were lower in orlistat than in placebo-treated subjects. Whether these results translate into reduced incidence of cardiovascular disease remains to be elucidated

Predictors of carotid endarterectomy in middle-aged individuals

The objective was to investigate which screening variables in a population study predicted carotid endarterectomy. Among 793 carotid endarterectomies performed at Malmo University Hospital between 1991 and 1998, 85 patients (14 females) were identified that had participated in a population screening between 1974 and 1991. Median time from screening to operation was 16 years (range 6-26 years). Screening variables were compared with corresponding values from the background screening population (n = 33261). As operated patients were older than the background population at screening (49 [37-60] vs. 46 [26-61] years; p < 0.0001), comparisons were age-adjusted. Operated patients had higher systolic blood pressure (SBP; 130 [126-133] vs. 125 [125-125] mmHg; p < 0.01), serum total cholesterol (6.1 [5.9-6.3] vs. 5.7 [5.7-5.7] mmol/l; p < 0.0001), serum triglyceride (1.4 [1.3-1.6] vs. 1.1 [1.1-1.1] mmol/l; p < 0.0001), serum glutamic acid transferase (0.46 [0.40-0.53] vs. 0.40 [0.40-0.41] microkat/l; p < 0.05), and plasma fibrinogen (3.77 [3.42-4.16] vs. 3.35 [3.30-3.41] mmol/l; p < 0.05) levels, a lower 120-min insulin/glucose ratio at an oral glucose tolerance test (OGTT; 0.48 [0.38-0.58] vs. 0.60 [0.59-0.61]; p < 0.05) and forced vital lung capacity (3.7 [3.6-3.9] vs. 3.9 [3.9-4.0] l/min; p < 0.05), and a higher prevalence of smoking at screening (68% vs. 45%; p < 0.0001). Smoking, SBP, serum total cholesterol, and the 120-min insulin/glucose ratio remained independent predictors for carotid surgery in multivariate analysis. No differences existed among patients operated on because of symptomatic and asymptomatic stenosis. In conclusion, increased SBP and total cholesterol, lower 2-h insulin/glucose ratio at an OGTT, and smoking predict carotid surgery at long-term follow-up

Fatality of acute coronary events in relation to hypertension and low-grade inflammation: a population-based cohort study.

Hypertension has been associated with increased case-fatality rates among individuals who subsequently suffer from acute coronary events. It is unknown whether inflammation modifies this relationship. This population-based study explored the effects of inflammation and hypertension on incidence of coronary event, and on the fatality of the future events. Blood pressure (BP) and five inflammation-sensitive plasma proteins (ISPs, fibrinogen, orosomucoid, alpha 1-antitrypsin, haptoglobin and ceruloplasmin) were determined in 6071 healthy men. During the mean follow-up of 19 years, 679 men had a first coronary event (non-fatal myocardial infarction or death from coronary heart disease). Of them, 197 (29%) were fatal cases (death during the first day). As expected, hypertension was associated with increased incidence of coronary events and increased proportion of fatal cases. At all levels of BP, high ISPs (>= 2 ISPs in top quartile) significantly added to the incidence of events. Men with high ISPs had the highest case-fatality rates. The difference in case-fatality rate between men with and without high ISPs was, however, significant only in men with normal BP (= 160/100 mm Hg) (40 vs 35%, P=0.32). High ISPs add to the incidence of coronary events at all levels of BP. Hypertension and inflammation are both independently associated with increased case-fatality in subjects who later have an acute coronary event. The influence of ISPs on the case-fatality rate seems to be most important in men with normal BP