ABSTRACT
Sucralose is a noncaloric artificial sweetener that is widely consumed worldwide and has been associated with alteration in glucose and insulin homeostasis. Unbalance in monocyte subpopulations expressing CD11c and CD206 hallmarks metabolic dysfunction but has not yet been studied in response to sucralose. Our goal was to examine the effect of a single sucralose sip on serum insulin and blood glucose and the percentages of classical, intermediate, and nonclassical monocytes in healthy young adults subjected to an oral glucose tolerance test (OGTT). This study was a randomized, placebo-controlled clinical trial. Volunteers randomly received 60 mL water as placebo (n = 20) or 48 mg sucralose dissolved in 60 mL water (n = 25), fifteen minutes prior to an OGTT. Blood samples were individually drawn every 15 minutes for 180 minutes for quantifying glucose and insulin concentrations. Monocyte subsets expressing CD11c and CD206 were measured at -15 and 180 minutes by flow cytometry. As compared to controls, volunteers receiving sucralose exhibited significant increases in serum insulin at 30, 45, and 180 minutes, whereas blood glucose values showed no significant differences. Sucralose consumption caused a significant 7% increase in classical monocytes and 63% decrease in nonclassical monocytes with respect to placebo controls. Pearson's correlation models revealed a strong association of insulin with sucralose-induced monocyte subpopulation unbalance whereas glucose values did not show significant correlations. Sucralose ingestion decreased CD11c expression in all monocyte subsets and reduced CD206 expression in nonclassical monocytes suggesting that sucralose does not only unbalance monocyte subpopulations but also alter their expression pattern of cell surface molecules. This work demonstrates for the first time that a 48 mg sucralose sip increases serum insulin and unbalances monocyte subpopulations expressing CD11c and CD206 in noninsulin-resistant healthy young adults subjected to an OGTT. The apparently innocuous consumption of sucralose should be reexamined in light of these results.
Subject(s)
Diabetes Mellitus, Type 2/metabolism , Monocytes/physiology , Sucrose/analogs & derivatives , Adult , Blood Glucose , CD11c Antigen/metabolism , Eating , Female , Glucose Tolerance Test , Healthy Volunteers , Humans , Insulin/metabolism , Lectins, C-Type/metabolism , Male , Mannose Receptor , Mannose-Binding Lectins/metabolism , Receptors, Cell Surface/metabolism , Sucrose/administration & dosage , Young AdultABSTRACT
BACKGROUND: In high-fat diet-fed mice, interleukin-1 beta (IL-1 beta) has been shown to play a key role in hepatic steatosis. However, it remains unknown whether IL-1 beta could be associated with different grades of steatosis in obese humans. MATERIALS AND METHODS: Morbidly obese patients (n = 124) aged 18-65 years were divided into four groups: no steatosis (controls), mild steatosis, moderate steatosis, and severe steatosis using abdominal ultrasound. IL-1 beta serum levels and liver function tests were measured and significant differences were estimated by one-way ANOVA followed by Tukey test. RESULTS: IL-1 beta serum levels significantly increased in morbidly obese patients with mild (11.38 ± 2.40 pg/ml), moderate (16.72 ± 2.47 pg/ml), and severe steatosis (23.29 ± 5.2 pg/ml) as compared to controls (7.78 ± 2.26 pg/ml). Liver function tests did not significantly change among different grades of steatosis. CONCLUSION: IL-1 beta serum levels associate better with steatosis degree than liver function tests in morbidly obese population.
ABSTRACT
Experimental evidence in mice suggests a role for interleukin- (IL-) 13 in insulin resistance and low-grade systemic inflammation. However, IL-13 serum levels have not been assessed in subjects with insulin resistance, and associations of IL-13 with parameters of low-grade systemic inflammation are still unknown. Our main goal was to examine the systemic levels of IL-13 in patients with insulin resistance, while also studying the relationship of IL-13 with anthropometric, metabolic, and low-grade systemic inflammatory markers. Ninety-two participants were included in the study and divided into insulin-resistant patients and noninsulin-resistant controls. Blood levels of IL-13, glucose, insulin, triglycerides, cholesterol, tumor necrosis factor-alpha (TNF-α), IL-10, proinflammatory (Mon-CD11c+CD206-), and anti-inflammatory (Mon-CD11c-CD206+) monocytes, as well as anthropometric parameters, were measured in all volunteers. Insulin-resistant patients showed 2.5-fold higher serum levels of IL-13 than controls (P < 0.0001) and significantly increased values of TNF-α and Mon-CD11c+CD206-, with concomitant reductions in IL-10 and Mon-CD11c-CD206+. Increased IL-13 was extraordinarily well associated with hyperglycemia (r = 0.7362) and hypertriglyceridemia (r = 0.7632) but unexpectedly exhibited no significant correlations with TNF-α (r = 0.2907), IL-10 (r = -0.3882), Mon-CD11c+CD206- (r = 0.2745) or Mon-CD11c-CD206+ (r = -0.3237). This study demonstrates that IL-13 serum levels are elevated in patients with insulin resistance without showing correlation with parameters of low-grade systemic inflammation.