Offspring subcutaneous adipose markers are sensitive to the timing of maternal gestational weight gain.

BACKGROUND: Excessive maternal weight gain during pregnancy impacts on offspring health. This study focused on the timing of maternal gestational weight gain, using a porcine model with mothers of normal pre-pregnancy weight. METHODS: Trial design ensured the trajectory of maternal gestational weight gain differed across treatments in early, mid and late gestation. Diet composition did not differ. On day 25 gestation, sows were assigned to one of five treatments: Control sows received a standard gestation diet of 2.3 kg/day (30 MJ DE/day) from early to late gestation (day 25-110 gestation). E sows received 4.6 kg food/day in early gestation (day 25-50 gestation). M sows doubled their food intake in mid gestation (day 50-80 gestation). EM sows doubled their food intake during both early and mid gestation (day 25-80 gestation). L sows consumed 3.5 kg food/day in late gestation (day 80-110 gestation). Offspring body weight and food intake levels were measured from birth to adolescence. Markers of lipid metabolism, hypertrophy and inflammation were investigated in subcutaneous adipose tissue of adolescent offspring. RESULTS: The trajectory of gestational weight gain differed across treatments. However total gestational weight gain did not differ except for EM sows who were the heaviest and fattest mothers at parturition. Offspring birth weight did not differ across treatments. Subcutaneous adipose tissue from EM offspring differed significantly from controls, with elevated mRNA levels of lipogenic (CD36, ACACB and LPL), nutrient transporters (FABP4 and GLUT4), lipolysis (HSL and ATGL), adipocyte size (MEST) and inflammation (PAI-1) indicators. The subcutaneous adipose depot from L offspring exhibited elevated levels of CD36, ACACB, LPL, GLUT4 and FABP4 mRNA transcripts compared to control offspring. CONCLUSIONS: Increasing gestational weight gain in early gestation had the greatest impact on offspring postnatal growth rate. Increasing maternal food allowance in late gestation appeared to shift the offspring adipocyte focus towards accumulation of fat. Mothers who gained the most weight during gestation (EM mothers) gave birth to offspring whose subcutaneous adipose tissue, at adolescence, appeared hyperactive compared to controls. This study concluded that mothers, who gained more than the recommended weight gain in mid and late gestation, put their offspring adipose tissue at risk of dysfunction.

Effect of Lactobacillus rhamnosus CGMCC1.3724 supplementation on weight loss and maintenance in obese men and women.

The present study investigated the impact of a Lactobacillus rhamnosus CGMCC1.3724 (LPR) supplementation on weight loss and maintenance in obese men and women over 24 weeks. In a double-blind, placebo-controlled, randomised trial, each subject consumed two capsules per d of either a placebo or a LPR formulation (1.6 × 10(8) colony-forming units of LPR/capsule with oligofructose and inulin). Each group was submitted to moderate energy restriction for the first 12 weeks followed by 12 weeks of weight maintenance. Body weight and composition were measured at baseline, at week 12 and at week 24. The intention-to-treat analysis showed that after the first 12 weeks and after 24 weeks, mean weight loss was not significantly different between the LPR and placebo groups when all the subjects were considered. However, a significant treatment × sex interaction was observed. The mean weight loss in women in the LPR group was significantly higher than that in women in the placebo group (P = 0.02) after the first 12 weeks, whereas it was similar in men in the two groups (P= 0.53). Women in the LPR group continued to lose body weight and fat mass during the weight-maintenance period, whereas opposite changes were observed in the placebo group. Changes in body weight and fat mass during the weight-maintenance period were similar in men in both the groups. LPR-induced weight loss in women was associated not only with significant reductions in fat mass and circulating leptin concentrations but also with the relative abundance of bacteria of the Lachnospiraceae family in faeces. The present study shows that the Lactobacillus rhamnosus CGMCC1.3724 formulation helps obese women to achieve sustainable weight loss.

Quinine controls body weight gain without affecting food intake in male C57BL6 mice.

BACKGROUND: Quinine is a natural molecule commonly used as a flavouring agent in tonic water. Diet supplementation with quinine leads to decreased body weight and food intake in rats. Quinine is an in vitro inhibitor of Trpm5, a cation channel expressed in taste bud cells, the gastrointestinal tract and pancreas. The objective of this work is to determine the effect of diet supplementation with quinine on body weight and body composition in male mice, to investigate its mechanism of action, and whether the effect is mediated through Trpm5. RESULTS: Compared with mice consuming AIN, a regular balanced diet, mice consuming AIN diet supplemented with 0.1% quinine gained less weight (2.89 ± 0.30 g vs 5.39 ± 0.50 g) and less fat mass (2.22 ± 0.26 g vs 4.33 ± 0.43 g) after 13 weeks of diet, and had lower blood glucose and plasma triglycerides. There was no difference in food intake between the mice consuming quinine supplemented diet and those consuming control diet. Trpm5 knockout mice gained less fat mass than wild-type mice. There was a trend for a diet-genotype interaction for body weight and body weight gain, with the effect of quinine less pronounced in the Trpm5 KO than in the WT background. Faecal weight, energy and lipid contents were higher in quinine fed mice compared to regular AIN fed mice and in Trpm5 KO mice compared to wild type mice. CONCLUSION: Quinine contributes to weight control in male C57BL6 mice without affecting food intake. A partial contribution of Trpm5 to quinine dependent body weight control is suggested.

Defining a Continuous Glucose Baseline to assess the impact of nutritional interventions.

Accurate and robust estimation of individuals' basal glucose level is a crucial measure in nutrition research but is typically estimated from one or more morning fasting samples. The use of Continuous Glucose Monitoring (CGM) devices presents an opportunity to define more robust basal glucose levels, which estimates can be generalized to any time of the day. However, to date, no standardized method has been delineated. The current paper seeks to define a reliable algorithm to characterize the individual's basal glucose level over 24 h from CGM measurements. Data drawn from four nutritional intervention studies performed on adults free from chronic diseases were used to define that basal glucose levels were optimally estimated using the 40th percentile of the previous 24 h CGM data. This simple algorithm provides a Continuous Glucose Baseline over 24 h (24 h-CGB) that is an unbiased and highly correlated estimator (r = 0.86, p-value < 0.01) of standard fasting glucose. We conclude that 24-CGB can provide reliable basal glucose estimates across the day while being more robust to interference than standard fasting glucose, adaptable to evolving daily routines and providing useful reference values for free-living nutritional intervention research in non-diabetic individuals.

The interrelationship between sleep, diet, and glucose metabolism.

Obesity and type 2 diabetes (T2D) are increasingly common worldwide. While these disorders have increased in prevalence over the past several decades, there has been a concomitant reduction in sleep duration. Short sleep duration has been associated with higher rates of obesity and T2D, and the causality of these associations and their directionality, continue to necessitate evaluation. In this review we consider the evidence that sleep is an intrinsic factor in the development of obesity and chronic metabolic disorders, such as insulin resistance and T2D, while evaluating a potential bi-directional association. We consider the evidence that diet and meal composition, which are known to impact glycemic control, may have both chronic and acute impact upon sleep. Moreover, we consider that postprandial nocturnal metabolism and peripheral glycemia may affect sleep quality. We propose putative mechanisms whereby acute effects of nighttime glucose excursions may lead to increased sleep fragmentation. We conclude that dietary manipulations, particularly with respect to carbohydrate quality, may confer sleep benefits. Future research may seek to evaluate the effectiveness of synergistic nutrient strategies to promote sleep quality, with particular attention to carbohydrate quality, quantity, and availability as well as carbohydrate to protein ratio.

Glucose variability in 6-12-month-old healthy infants.

Background: Metabolic programming of glucose homeostasis in the first 1,000 days of life may impact lifelong metabolic and cardiovascular health. Continuous glucose monitoring (CGM) devices may help measure the impact of dietary intake on glucose rhythms and metabolism in infants during the complementary feeding period. Objectives: Demonstrate the feasibility of CGM to measure and quantify glucose variability in response to infant feeding and to evaluate associations between macronutrient meal composition and glucose variability. Methods: The "FreeStyle Libre Pro®" device interstitial glucose meter was applied to the anterior thigh of 10 healthy 6-12-month-old infants. Parents recorded food intake, time of feeding, and used daily dairies to record sleep time and duration. Descriptive statistics were employed for food intake, sleep and key glycemic parameters over three full days. Mixed linear models were used to assess glycemic changes. Results: Mid-day, afternoon, and evening feeds contained >30 g carbohydrate and induced higher 2-h iAUC (3.42, 3.41, and 3.50 mmol/L*h respectively) compared to early and mid-morning feedings with ≤25 g carbohydrates (iAUC 2.72 and 2.81 mmol/L*h, p < 0.05). Early morning and evening milk feedings contained approximately 9 g of fat and induced a longer time to reach maximal glucose value (Tmax; 75 and 68 min, respectively) compared to lower fat feedings (2.9-5.9 g; Tmax range: 34-60 min; p < 0.05). Incremental glucose value at time of food intake (C0) increased significantly from 0.24 ± 0.39 mM in early morning to 1.07 ± 0.57 mM in the evening (p < 0.05). Over the day, 70% of glucose values remained within the normal range (3.5-5.5 mmol/L), 10% were between 5.5-10 mmol/L, and 20% were < 3.5 mmol/L. Conclusion: Our data support the feasibility of using CGM to measure glucose in 6-12-month-old infants. The observation of possible diurnal glucose variability and typical glucose values may have implications for future studies investigating metabolic adaptation to nutritional intake in early life.

Effects of Dietary Carbohydrate Profile on Nocturnal Metabolism, Sleep, and Wellbeing: A Review.

Sleep is a crucial biological function and a well-established driver of health and wellbeing across the lifespan. In this review, we describe how sleep in humans is associated with specific circadian metabolic and physiological changes, and how the organization of sleep-wake states is related to regulation of nocturnal metabolism during fasting. Among the modifiable factors that can contribute to sleep-related benefits, emerging evidence suggests that diet and nocturnal changes in glucose regulation are strong determinants of sleep quality. Here, we review studies that have explored the importance of quantity and quality of dietary carbohydrates and proteins in modulation of sleep and sleep-related health benefits. Future research may guide the creation of nutritional solutions to improve sleep, which could lead to positive changes in health, wellbeing, and overall quality of life.

Effect of Different Nutritional Supplements on Glucose Response of Complete Meals in Two Crossover Studies.

Postprandial hyperglycemia is an important risk factor in the development and progression of type-2 diabetes and cardiometabolic diseases. Therefore, maintaining a low postprandial glucose response is key in preventing these diseases. Carbohydrate-rich meals are the main drivers of excessive glycemic excursions during the day. The consumption of whey protein premeals or mulberry leaf extract was reported to reduce postprandial glycemia through different mechanisms of action. The efficacy of these interventions was shown to be affected by the timing of the consumption or product characteristics. Two randomised crossover studies were performed, aiming to identify the optimal conditions to improve the efficacy of these nutritional supplements in reducing a glycemic response. The acute postprandial glycemic response was monitored with a continuous glucose monitoring device. The first study revealed that a preparation featuring 10 g of whey protein microgel reduced the postprandial glucose response by up to 30% (p = 0.001) and was more efficient than the whey protein isolates, independently of whether the preparation was ingested 30 or 10 min before a complete 320 kcal breakfast. The second study revealed that a preparation featuring 250 mg mulberry leaf extract was more efficient if it was taken together with a complete 510 kcal meal (−34%, p < 0.001) rather than ingested 5 min before (−26%, p = 0.002). These findings demonstrate that the efficacy of whey proteins premeal and mulberry leaf extracts can be optimised to provide potential nutritional solutions to lower the risk of type-2 diabetes or its complications.

Rosemary (Rosmarinus officinalis L.) leaf extract limits weight gain and liver steatosis in mice fed a high-fat diet.

The objective of this study was to investigate the effects of rosemary (Rosmarinus officinalis L.) leaf extract (RE) on the prevention of weight gain and associated metabolic disorders in mice fed a high-fat diet. For this purpose, RE was administered for 50 days at 20 or 200 mg/kg body weight (BW) to mice fed a high-fat diet. Body weight was monitored during the study and body composition was measured before and at the end of the intervention. Glucose tolerance, assessed by an intraperitoneal glucose tolerance test (IPGTT), and hepatic and faecal lipid contents were determined at the end of the study. Treatment with 200 mg/kg BW of RE induced a significant reduction of weight and fat mass gain (-64% and -57%, respectively) associated with an increase of faecal lipid excretion. This effect appears to be related to the inhibition of pancreatic lipase activity induced by RE, as demonstrated IN VITRO. While glucose tolerance and fasting glycaemia were not affected by RE treatment, hepatic triglyceride levels were decreased by 39% in RE-treated mice. Administration of the lower dose of RE (20 mg/kg BW) was ineffective on all the parameters measured. In conclusion, our results demonstrate that consumption of 200 mg/kg BW of RE can limit weight gain induced by a high-fat diet and protect against obesity-related liver steatosis.

High or low glycemic index (GI) meals at dinner results in greater postprandial glycemia compared with breakfast: a randomized controlled trial.

INTRODUCTION: While circadian control of glucose metabolism is well known, how glycemic index (GI) of carbohydrate-rich meals interacts with time of consumption (breakfast or dinner) to influence postprandial (PP) glucose homeostasis is less well established. The objective of the study was to assess markers of PP glucose homeostasis following high or low GI test meals (TM) consumed either at breakfast or at dinner and following consumption of the subsequent standardized meals (SSM). RESEARCH DESIGN AND METHODS: Randomized crossover trial in 34 healthy, Chinese, elderly volunteers (mean±SEM age, 56.8±0.83 years), who completed 4 separate study sessions per-protocol, consisting of a high-GI breakfast, low-GI breakfast, high-GI dinner and low-GI dinner TM, followed by a SSM at the subsequent eating occasion. Blood samples were taken for 3 hours after each TM and SSM for glucose, insulin, glucagon, free fatty acids (FFA) and triglycerides (TG) measurements. RESULTS: Consuming TM at dinner produced greater PP glycemia than breakfast both after TM and SSM (both p<0.0001), irrespective of GI. High-GI TM also produced greater PP glycemia than low-GI TM, both after TM and SSM (both p<0.01), irrespective of time of consumption. No interaction between GI and time were found on PP glycemia, indicating parallel, but independent effects. Combined total areas under the curve of TM+SSM for PP glucose (p<0.0001), PP TG (p<0.0001) and PP FFA (p<0.0001) were all greater when TM taken during dinner compared with breakfast. CONCLUSIONS: Carbohydrate-rich meals consumed at dinner leads to significantly worse PP glucose homeostasis than when consumed at breakfast, on top of the independent GI effect of the meal. This may have implications to future type 2 diabetes risk. Moreover, future studies investigating GI/glycemic load (GL) and disease risk associations should factor in timing of GL consumption as an additional variable. TRIAL REGISTRATION NUMBER: NCT02927600.

The effect of coffee consumption on insulin sensitivity and other biological risk factors for type 2 diabetes: a randomized placebo-controlled trial.

BACKGROUND: In observational studies, coffee consumption has been consistently associated with a lower risk of type 2 diabetes mellitus. Trials examining the effect of coffee consumption on glucose metabolism have been limited by the use of surrogate insulin sensitivity indices, small sample sizes, lack of blinding, and short follow-up duration. OBJECTIVES: We aimed to overcome limitations of previously conducted coffee trials in a randomized placebo-controlled trial of the effect of coffee consumption on insulin sensitivity. METHODS: We conducted a 24-wk randomized placebo-controlled trial in 126 overweight, non-insulin sensitive (HOMA-IR ≥1.30), Chinese, Malay, and Asian-Indian males and females aged 35-69 y. Participants were randomly assigned to receive 4 cups of instant regular coffee (n = 62) or 4 cups of a coffee-like placebo beverage (n = 64) per day. The primary outcome was the amount of glucose metabolized per kilogram of body weight per minute (Mbw) assessed during steady-state conditions with a hyperinsulinemic euglycemic clamp. Secondary outcomes included other clamp-based insulin sensitivity measures, biological mediators of insulin sensitivity, and measures of fasting glucose metabolism. RESULTS: Coffee consumption did not significantly change insulin sensitivity compared with placebo (percentage mean difference in Mbw = 4.0%; 95% CI: -8.3, 18.0%; P = 0.53). Furthermore, no significant differences in fasting plasma glucose (2.9%; 95% CI: -0.4, 6.3%; P = 0.09) or biological mediators of insulin resistance, such as plasma adiponectin (2.3%; 95% CI: -1.4, 6.2%; P = 0.22), were observed between coffee and placebo groups over 24 wk of intervention. Participants in the coffee arm experienced a loss of fat mass (FM) (-3.7%; 95% CI: -6.3, -1.1%; P = 0.006) and reduction in urinary creatinine concentrations (-21.2%; 95% CI: -31.4, -9.5%; P = 0.001) compared with participants in the placebo arm over 24 wk of intervention. CONCLUSIONS: Consuming 4 cups/d of caffeinated coffee for 24 wk had no significant effect on insulin sensitivity or biological mediators of insulin resistance but was associated with a modest loss of FM and reduction in urinary creatinine concentrations.This trial was registered at clinicaltrials.gov as NCT01738399. Registered on November 28, 2012. Trial sponsor: Nestlé Research, Lausanne, Switzerland. Trial site: National University of Singapore.

Salivary α-amylase copy number is not associated with weight trajectories and glycemic improvements following clinical weight loss: results from a 2-phase dietary intervention study.

BACKGROUND: Several studies recently reported contradicting results regarding the link between amylase 1 (AMY1) copy numbers (CNs), obesity, and type 2 diabetes. OBJECTIVE: The aim of this study was to assess the impact of AMY1 CN on anthropometrics and glycemic outcomes in obese individuals following a 2-phase dietary weight loss intervention. METHODS: Using the paralog ratio test, AMY1 CNs were accurately measured in 761 obese individuals from the DiOGenes study. Subjects first underwent an 8-wk low-calorie diet (LCD, at 800 kcal/d) and then were randomly assigned to a 6-mo weight maintenance dietary (WMD) intervention with arms having different glycemic loads. RESULTS: At baseline, a modest association between AMY1 CN and BMI (P = 0.04) was observed. AMY1 CN was not associated with baseline glycemic variables. In addition, AMY1 CN was not associated with anthropometric or glycemic outcomes following either LCD or WMD. Interaction analyses between AMY1 CN and nutrient intake did not reveal any significant association with clinical parameters (at baseline and following LCD or WMD) or when testing gene × WMD interactions during the WMD phase. CONCLUSION: In the absence of association with weight trajectories or glycemic improvements, the AMY1 CN cannot be considered as an important biomarker for response to a clinical weight loss and weight maintenance programs in overweight/obese subjects. This trial was registered at www.clinicaltrials.gov as NCT00390637.

Chronotype: Implications for Epidemiologic Studies on Chrono-Nutrition and Cardiometabolic Health.

Chrono-nutrition is an emerging research field in nutritional epidemiology that encompasses 3 dimensions of eating behavior: timing, frequency, and regularity. To date, few studies have investigated how an individual's circadian typology, i.e., one's chronotype, affects the association between chrono-nutrition and cardiometabolic health. This review sets the directions for future research by providing a narrative overview of recent epidemiologic research on chronotype, its determinants, and its association with dietary intake and cardiometabolic health. Limited research was found on the association between chronotype and dietary intake in infants, children, and older adults. Moreover, most of the evidence in adolescents and adults was restricted to cross-sectional surveys with few longitudinal cohorts simultaneously collecting data on chronotype and dietary intake. There was a gap in the research concerning the association between chronotype and the 3 dimensions of chrono-nutrition. Whether chronotype modifies the association between diet and cardiometabolic health outcomes remains to be elucidated. In conclusion, further research is required to understand the interplay between chronotype, chrono-nutrition, and cardiometabolic health outcomes.

Effects of a Diet-Based Weight-Reducing Program with Probiotic Supplementation on Satiety Efficiency, Eating Behaviour Traits, and Psychosocial Behaviours in Obese Individuals.

This study evaluated the impact of probiotic supplementation (Lactobacillus rhamnosus CGMCC1.3724 (LPR)) on appetite sensations and eating behaviors in the context of a weight-reducing program. Obese men (n = 45) and women (n = 60) participated in a double-blind, randomized, placebo-controlled trial that included a 12-week weight loss period (Phase 1) based on moderate energy restriction, followed by 12 weeks of weight maintenance (Phase 2). During the two phases of the program, each subject consumed two capsules per day of either a placebo or a LPR formulation (10 mg of LPR equivalent to 1.6 108 CFU/capsule, 210 mg of oligofructose, and 90 mg of inulin). The LPR supplementation increased weight loss in women that was associated with a greater increase in the fasting desire to eat (p = 0.03). On the other hand, satiety efficiency (satiety quotient for desire to eat) at lunch increased (p = 0.02), whereas disinhibition (p = 0.05) and hunger (p = 0.02) scores decreased more in the LPR-treated women, when compared with the female control group. Additionally, the LPR female group displayed a more pronounced decrease in food craving (p = 0.05), and a decrease in the Beck Depression Inventory score (p = 0.05) that was significantly different from the change noted in the placebo group (p = 0.02), as well as a higher score in the Body Esteem Scale questionnaire (p = 0.06). In men, significant benefits of LPR on fasting fullness and cognitive restraint were also observed. Taken together, these observations lend support to the hypothesis that the gut-brain axis may impact appetite control and related behaviors in obesity management.

C/EBPalpha regulates human adiponectin gene transcription through an intronic enhancer.

Adiponectin is an adipose-derived hormone that enhances insulin sensitivity and plays an important role in regulating energy homeostasis. Here, we demonstrate that the DNA encoding the first intron of the human adiponectin gene contains an intronic enhancer that regulates adiponectin gene expression in an adipose tissue-specific manner. Insertion of the DNA encoding the first intron into reporter constructs containing the proximal adiponectin promoter (Pro-Int1-Luc) resulted in a 20-fold increase in activity relative to the promoter alone in 3T3-L1 adipocytes. Coexpression of CCAAT/enhancer-binding protein (C/EBP)alpha increased luciferase activity of the Pro-Int1-Luc construct approximately 75-fold but had no effect on the constructs containing the proximal adiponectin promoter alone. At least eight potential C/EBPalpha response elements are located between +3000 to +10000 nucleotides within the DNA encoding the first intron, including a 34-bp core sequence for the intronic enhancer that contains three tandem C/EBPalpha response elements. However, the intronic enhancer is not conserved between human and mouse. Overexpression or siRNA-mediated knockdown of endogenous C/EBPalpha significantly increased or decreased, respectively, adiponectin mRNA levels in differentiated human Chub-S7 adipocytes, while neither C/EBPbeta nor C/EBPdelta significantly affected adiponectin expression in mature adipocytes. Thus, C/EBPalpha is a key transcription factor for full activation of human adiponectin gene transcription in mature adipocytes through interaction with response elements in the intronic enhancer.

Liver X receptor preferentially activates de novo lipogenesis in human preadipocytes.

The liver X receptor (LXR) was demonstrated to play a key role in cholesterol metabolism in liver, intestine and macrophage. However, its function on the regulation of preadipocyte differentiation remains unclear since contradictory results were reported. The objective of the present study was to unravel the functionality of LXR in human preadipocytes. We show that the LXR agonist T0901317 strongly stimulated the expression of SREBP-1c and the lipogenic enzymes ACC-1, FAS and SCD-1 in both the human preadipose cell line Chub-S7 as well as human primary stromal vascular fraction (SVF) cells. The effects on gene expression were associated with the stimulation of de novo lipogenesis in both cell models, resulting in the induction of lipid accumulation. In contrast with a PPARgamma agonist (BRL49653), T0901317 enhanced only slightly the expression of PPARgamma dependent genes (PPARgamma, aP2 and adiponectin) in Chub-S7 cells and failed to change their expression in human SVF cells. These results show that LXR stimulated preferentially triglyceride accumulation in human preadipocytes via the induction of de novo lipogenesis, rather than activating the differentiation process through PPARgamma activation.

A randomized placebo-controlled trial of the effect of coffee consumption on insulin sensitivity: Design and baseline characteristics of the Coffee for METabolic Health (COMETH) study.

BACKGROUND: Coffee consumption has been consistently associated with a lower risk of type 2 diabetes mellitus in cohort studies. In addition, coffee components increased insulin sensitivity in animal models. However, data from intervention studies on the effect of coffee consumption on glucose metabolism have been limited by small sample sizes, lack of blinding, short follow-up duration and the use of surrogate indices of insulin sensitivity. We designed the Coffee for Metabolic Health (COMETH) study to evaluate the effect of coffee consumption on insulin sensitivity. METHODOLOGY: The COMETH study is a double-blind randomized placebo-controlled 24-week trial. Participants were overweight, male and female habitual coffee consumers who were of Chinese, Malay and Asian-Indian ethnicity. We excluded smokers, persons with diabetes, and persons with low insulin resistance (HOMA-IR < 1.30). Participants were randomly assigned to receive daily 4 cups of instant regular coffee or 4 cups of a coffee-like placebo beverage. The hyperinsulinemic euglycemic clamp was performed at baseline and at the end of 24 weeks to determine changes in the bodyweight standardized M-value. Secondary outcomes included changes in fasting glucose and insulin sensitivity mediators such as adiponectin, markers of inflammation, liver function, and oxidative stress.We enrolled 128 participants, 126 (57.1% males; aged 35-67 years) of whom completed baseline assessments. DISCUSSION: If improvement in insulin sensitivity in the coffee group is significantly greater than that of the placebo group, this would support the hypothesis that coffee consumption reduced risk of type 2 diabetes through biological pathways involving insulin sensitivity. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01738399. Registered on 28 November 2012. Trial Sponsor: Nestlé Research Center, Lausanne, Switzerland. Trial Site: National University of Singapore.

Immortalization of human preadipocytes.

Primary human preadipocytes in culture are characterized by a low proliferative capacity associated with a rapid decline of differentiation ability during subculturing; thereby limiting their use as cellular model. Cellular immortalization constitutes an interesting approach for establishing cell lines presenting an unlimited life span and a maintained differentiation capacity. Different procedures for developing immortalized human preadipocytes are discussed in this review. Transformation of human preadipocytes with the simian virus 40 large T-antigen (SV40 T-Ag) permitted the development of immortalized cells; however these cells could not maintain their capacity to differentiate into adipocytes. This limitation may be explained by the ability of SV40 T-Ag to inhibit transcriptional factors involved in the differentiation of preadipocyte. Reconstitution of the telomerase activity by stable expression of the hTERT (human telomerase catalytic subunit) gene was able to partially extend the lifespan of primary preadipocytes but not to promote cellular immortalization. However, a combined expression of hTERT and the E7 oncoprotein of human papillomavirus type 16, generated human preadipocytes with both an unlimited life span and a preserved adipogenic potential. This approach appears to be an effective method for establishing human preadipose cell lines for studying adipocyte differentiation and metabolism.

Coffee consumption attenuates short-term fructose-induced liver insulin resistance in healthy men.

BACKGROUND: Epidemiologic and experimental data have suggested that chlorogenic acid, which is a polyphenol contained in green coffee beans, prevents diet-induced hepatic steatosis and insulin resistance. OBJECTIVE: We assessed whether the consumption of chlorogenic acid-rich coffee attenuates the effects of short-term fructose overfeeding, dietary conditions known to increase intrahepatocellular lipids (IHCLs), and blood triglyceride concentrations and to decrease hepatic insulin sensitivity in healthy humans. DESIGN: Effects of 3 different coffees were assessed in 10 healthy volunteers in a randomized, controlled, crossover trial. IHCLs, hepatic glucose production (HGP) (by 6,6-d2 glucose dilution), and fasting lipid oxidation were measured after 14 d of consumption of caffeinated coffee high in chlorogenic acid (C-HCA), decaffeinated coffee high in chlorogenic acid, or decaffeinated coffee with regular amounts of chlorogenic acid (D-RCA); during the last 6 d of the study, the weight-maintenance diet of subjects was supplemented with 4 g fructose · kg(-1) · d(-1) (total energy intake ± SD: 143 ± 1% of weight-maintenance requirements). All participants were also studied without coffee supplementation, either with 4 g fructose · kg(-1) · d(-1) (high fructose only) or without high fructose (control). RESULTS: Compared with the control diet, the high-fructose diet significantly increased IHCLs by 102 ± 36% and HGP by 16 ± 3% and decreased fasting lipid oxidation by 100 ± 29% (all P < 0.05). All 3 coffees significantly decreased HGP. Fasting lipid oxidation increased with C-HCA and D-RCA (P < 0.05). None of the 3 coffees significantly altered IHCLs. CONCLUSIONS: Coffee consumption attenuates hepatic insulin resistance but not the increase of IHCLs induced by fructose overfeeding. This effect does not appear to be mediated by differences in the caffeine or chlorogenic acid content. This trial was registered at clinicaltrials.gov as NCT00827450.