Sridevi Krishnan

Growth and Morbidity of Gambian Infants are Influenced by Maternal Milk Oligosaccharides and Infant Gut Microbiota

Human milk oligosaccharides (HMOs) play an important role in the health of an infant as substrate for beneficial gut bacteria. Little is known about the effects of HMO composition and its changes on the morbidity and growth outcomes of infants living in areas with high infection rates. Mother’s HMO composition and infant gut microbiota from 33 Gambian mother/infant pairs at 4, 16, and 20 weeks postpartum were analyzed for relationships between HMOs, microbiota, and infant morbidity and growth. The data indicate that lacto-N-fucopentaose I was associated with decreased infant morbidity, and 3′-sialyllactose was found to be a good indicator of infant weight-for-age. Because HMOs, gut microbiota, and infant health are interrelated, the relationship between infant health and their microbiome were analyzed. While bifidobacteria were the dominant genus in the infant gut overall, Dialister and Prevotella were negatively correlated with morbidity, and Bacteroides was increased in infants with abnormal calprotectin. Mothers nursing in the wet season (July to October) produced significantly less oligosaccharides compared to those nursing in the dry season (November to June). These results suggest that specific types and structures of HMOs are sensitive to environmental conditions, protective of morbidity, predictive of growth, and correlated with specific microbiota.

Zumba® dance improves health in overweight/obese or type 2 diabetic women.

OBJECTIVE To evaluate the feasibility and health improvements from a Zumba® intervention in overweight/obese women. METHODS Twenty-eight (14 type 2 diabetic and 14 non-diabetic) over-weight/obese women (BMI: 37.3±1.5 kg/m(2)) 50.8±1.8 y of age, completed a 16-week intervention attending Zumba® dance classes 3 days/week, 60 minutes/class. We measured aerobic fitness, body weight, body fat %, and motivation to exercise before and after the study. RESULTS Intrinsic motivation to exercise (p < .05) and aerobic fitness (1.01 ± 0.40 mL/kg/min, p < .05) improved, and the participants lost body weight (-1.05 ± 0.55kg, p < .05) and body fat% (-1.2 ± 0.6%, p < .01). CONCLUSION The Zumba® intervention improved health and physical fitness in women.

Association between circulating endogenous androgens and insulin sensitivity changes with exercise training in midlife women.

ObjectiveAging induces a shift in circulating hormones in women, accompanied by weight gain during the late reproductive, menopausal transition, and postmenopausal years. Exercise has been shown to counter weight gain; however, it might increase circulating androgens. A 6-month aerobic and resistance training exercise regimen was implemented to examine interrelationships between circulating sex hormones, body composition, aerobic capacity, insulin sensitivity, and insulin resistance. MethodsTwenty-eight women, aged 42 to 52 years, completed the 6-month intervention study. They were randomly assigned to either a control (CON; n = 10) group—and maintained their sedentary lifestyle—or an exercise intervention (EXE; n = 18) group. The exercise intervention consisted of combined aerobic and resistance workouts scheduled 6 days/week for 60 minutes/day. Body weight, composition, VO2 peak, plasma insulin, glucose, lipid profile, estradiol, testosterone, progesterone, dehydroepiandrosterone, and dehydroepiandrosterone sulfate (DHEAS) were measured at baseline and on month 6. Insulin sensitivity was estimated using the insulin sensitivity index and the quantitative insulin sensitivity check index, whereas insulin resistance was estimated using the homeostatic model for insulin resistance. ResultsThere was a trend toward increased DHEAS in both groups (P < 0.1), but not as a function of the intervention. Insulin sensitivity index increased in the EXE group compared with the CON group (P < 0.01). Multiple linear regression indicated that, at 6 months, DHEAS was a negative contributor to insulin sensitivity in the EXE group, but not in the CON group. ConclusionsIn midlife women, an increase in circulating DHEAS, such as that previously reported during the menopausal transition, is associated with higher insulin resistance, but exercise can mitigate this risk by improving insulin sensitivity, thereby countering the effects of DHEAS.

Estradiol, SHBG and leptin interplay with food craving and intake across the menstrual cycle ☆

OBJECTIVE To understand the association between ovarian hormones, non-acute satiety hormones and craving calorie dense foods in the luteal phase. METHODS 17 premenopausal women, mean age 23.2 y, mean BMI 22.4kg/m(2) with regular menstrual cycles were studied during late follicular (FP) and luteal phases (LP). Estradiol, progesterone, DHEAS, SHBG, insulin and leptin, were measured in fasting samples. The validated Food Craving Inventory was used to record the types of foods volunteers habitually ate - rich in fat, carbohydrate or sweet taste, as well as craved during the LP of their menstrual cycle. RESULTS Estradiol was inversely associated with leptin in FP (r=-0.62, p=0.01). Leptin was inversely associated with habitual intake of sweet foods, in both phases (FP: r=-0.64, p=0.01; LP: r=-0.63, p=0.01). SHBG in LP was positively associated with craving sweet and carbohydrate rich foods. Hierarchical cluster analysis revealed two groups of women, one with high estradiol, high estradiol/leptin ratio, high sweet and carbohydrate cravings (p<0.05); the other group had lower estradiol, lower estradiol/leptin ratio, and reported less craving. CONCLUSIONS The estradiol-leptin axis may be a determinant of luteal phase craving and habitual food intake in menstruating women. CLINICAL TRIAL REGISTRATION NUMBER NCT01407692.

Variation in metabolic responses to meal challenges differing in glycemic index in healthy women: Is it meaningful?

BackgroundEstablished clinical tests are commonly used in disease diagnosis, but tools that enhance identification of metabolic dysfunctions are needed. This study was conducted to identify typical and atypical metabolite temporal patterns in response to paired meal challenge tests.DesignMetabolic responses to high and low glycemic index (GI) meals were tested in 24 healthy pre-menopausal women, aged 20-50 y, with BMI of 25-30 kg/m2 using a cross-over design. On test days, blood glucose, insulin, leptin and non-esterified fatty acids were measured after an overnight fasting, and for 8 h following test meal consumption. The data were range scaled, and multivariate statistics were used to assess the presence of distinct response groups to the meal challenge tests.ResultsAs expected, participants showed higher circulating glucose and insulin in response to the high GI compared to the low GI meal challenge. However, using range-scaling and Principal Component Analysis, three distinct groups were identified based on differential responses to the paired challenges. Members of the most populated group (n = 18) displayed little deviation from the expected response to the two meal challenges. Two minor groups (n = 3/group) with distinct responses were observed, one suggestive of sub-clinical insulin resistance, and the other suggestive of hyperleptinemia.ConclusionsThe differential responses of glucose, insulin and leptin to low and high glycemic test meals revealed three response groups. Dietary intervention studies traditionally evaluate group responses, and aim to identify the overall effect in the population studied. In contrast, our study analyzed the variance in the meal challenge responses, using an integrated physiological approach, rather than a reductionist approach. This phenotyping approach may be useful for detecting subclinical metabolic dysfunctions, and it could contribute to improved personalized nutrition management. This study is registered in ClinicalTrials.gov, record #200210295

HDL Glycoprotein Composition and Site-Specific Glycosylation Differentiates Between Clinical Groups and Affects IL-6 Secretion in Lipopolysaccharide -Stimulated Monocytes

The goal of this pilot study was to determine whether HDL glycoprotein composition affects HDL’s immunomodulatory function. HDL were purified from healthy controls (n = 13), subjects with metabolic syndrome (MetS) (n = 13), and diabetic hemodialysis (HD) patients (n = 24). Concentrations of HDL-bound serum amyloid A (SAA), lipopolysaccharide binding protein (LBP), apolipoprotein A-I (ApoA-I), apolipoprotein C-III (ApoC-III), α-1-antitrypsin (A1AT), and α-2-HS-glycoprotein (A2HSG); and the site-specific glycovariations of ApoC-III, A1AT, and A2HSG were measured. Secretion of interleukin 6 (IL-6) in lipopolysaccharide-stimulated monocytes was used as a prototypical assay of HDL’s immunomodulatory capacity. HDL from HD patients were enriched in SAA, LBP, ApoC-III, di-sialylated ApoC-III (ApoC-III2) and desialylated A2HSG. HDL that increased IL-6 secretion were enriched in ApoC-III, di-sialylated glycans at multiple A1AT glycosylation sites and desialylated A2HSG, and depleted in mono-sialylated ApoC-III (ApoC-III1). Subgroup analysis on HD patients who experienced an infectious hospitalization event within 60 days (HD+) (n = 12), vs. those with no event (HD−) (n = 12) showed that HDL from HD+ patients were enriched in SAA but had lower levels of sialylation across glycoproteins. Our results demonstrate that HDL glycoprotein composition, including the site-specific glycosylation, differentiate between clinical groups, correlate with HDL’s immunomodulatory capacity, and may be predictive of HDL’s ability to protect from infection.

Running Performance with Nutritive and Non-Nutritive Sweetened Mouth Rinses.

Using mouth rinse (MR) with carbohydrate during exercise has been shown to act as an ergogenic aid. PURPOSE To investigate if nutritive or nonnutritive sweetened MR affects exercise performance and to assess the influence of sweetness intensity on endurance performance during a time trial (TT). METHODS This randomized, single-blinded study had 4 treatment conditions. Sixteen subjects (9 men, 7 women) completed a 12.8-km TT 4 different times. During each TT, subjects mouth-rinsed and expectorated a different solution at time 0 and every 12.5% of the TT. The 4 MR solutions were sucrose (S) (sweet taste and provides energy of 4 kcal/g), a lower-intensity sucralose (S1:1) (artificial sweetener that provides no energy but tastes sweet), a higher-intensity sucralose (S100:1), and water as control (C). Completion times for each TT, heart rate (HR), and ratings of perceived exertion (RPE) were also recorded. RESULTS Completion time for S was faster than for C (1:03:47 ± 00:02:17 vs 1:06:56 ± 00:02:18, respectively; P < .001) and showed a trend to be faster vs S100:1 (1:03:47 ± 00:02:17 vs 1:05:38 ± 00:02:12, respectively; P = .07). No other TT differences were found. Average HR showed a trend to be higher for S vs C (P = .08). The only difference in average or maximum RPE was for higher maximum RPE in C vs S1:1 (P = .02). CONCLUSION A sweet-tasting MR did improve endurance performance compared with water in a significant manner (mean 4.5% improvement; 3+ min.); however, the presence of energy in the sweet MR appeared necessary since the artificial sweeteners did not improve performance more than water alone.

Echinacea-Based Dietary Supplement Does Not Increase Maximal Aerobic Capacity in Endurance-Trained Men and Women.

ABSTRACT Purpose: To determine if an echinacea-based dietary supplement (EBS) provided at two different doses (a regular dose (RD), 8,000 mg/day, vs. a double dose (DD), 16,000 mg/day) would increase erythropoietin (EPO) and other blood markers involved in improving aerobic capacity and maximal oxygen consumption (VO2max) in endurance-trained men. Secondly, to determine if any sex differences exist between male and female endurance-trained athletes. Methods: Forty-five endurance athletes completed three visits during a 35-day intervention. Participants were randomized into placebo (PLA; n = 8 men, n = 7 women), RD of EBS (n = 7 men, n = 8 women), or DD of EBS (n = 15 men) for the 35-day intervention period. At baseline, weight, body composition, and VO2max were measured. Blood was drawn to measure EPO, ferritin, red blood cells, white blood cells, hemoglobin, and hematocrit. At the mid-intervention visit, blood was collected. At the post-intervention visit, all measurements from the baseline visit were obtained once again. Results: There was a significant increase in VO2max for endurance-trained men in PLA (increase of 2.8 ± 1.5 ml kg−1 min−1, p = .01) and RD of EBS (increase of 2.6 ± 1.8 ml kg−1 min−1, p = .04), but not in DD of EBS (p = .96). Importantly, there was no difference in the change in VO2max between PLA and RD of EBS. For endurance-trained women, VO2max did not change in either treatment (PLA: −0.7 ± 1.7 ml kg−1 min−1, p = .31; RD of EBS: −0.2 ± 2.4 ml kg−1 min−1, p = .80). There were no significant changes in any blood parameter across visits for any treatment group. Conclusions: This EBS should not be recommended as a means to improve performance in endurance athletes.

Structural equation modeling of food craving across the menstrual cycle using behavioral, neuroendocrine, and metabolic factors

OBJECTIVE To identify associations between circulating endocannabinoids and craving during the luteal phase of the menstrual cycle. This report is a secondary analysis of a trial registered in clinicaltrials.gov as NCT01407692. METHODS Seventeen premenopausal women were studied during the follicular and luteal phases of their menstrual cycle. Previously we had reported fasting plasma estradiol, progesterone, leptin associations with luteal phase cravings for carbohydrate, fat, sweet-rich foods, and eating behavior. Here, we measured fasting plasma endocannabinoids (ECs) endocannabinoid-like substances (ECLs), and postprandial metabolic responses to a mixed meal challenge. Structural equation modeling was used to evaluate relationships between measured variables and cravings. RESULTS Oleoylethanolamide (OEA) and postprandial lipids were inversely associated with craving sweet-rich foods, while progesterone was positively associated (RMSEA = 0.041, χ2 p: 0.416 i.e. hypothetical and physiological models not different). OEA, progesterone and disinhibition were positively associated with craving carbohydrates (RMSEA: <0.001, χ2 p: 0.919). ECs and ECLs combined were stronger predictors of craving than clinical metabolic parameters, ECs only, satiety hormones or gonadocorticoids. CONCLUSIONS Our theoretical model suggests that ECs and ECLs influence craving. Since these metabolites can be modulated via dietary fat intake, they could be potential targets to alter menstrual cycle cravings. CLINICAL TRIAL REGISTRATION NUMBER NCT01407692.

Impact of dietary fat composition on prediabetes: a 12-year follow-up study.

OBJECTIVE Dietary fatty acid composition likely affects prediabetic conditions such as isolated impaired fasting glucose (IFG) or impaired glucose tolerance (IGT); however, this risk has not been evaluated in a large population nor has it been followed prospectively. DESIGN Diet, physical activity, anthropometric, socio-economic and blood glucose data from the Atherosclerosis Risk in Communities (ARIC) study were obtained from BioLINCC. Cox proportional hazards regression models were used to evaluate associations of dietary SFA, MUFA, PUFA, n-3 fatty acid (FA) and n-6 FA intakes with incidence of one (isolated IFG) or two (IFG with IGT) prediabetic conditions at the end of 12-year follow-up. SETTING Study volunteers were from counties in North Carolina, Mississippi, Minnesota and Maryland, USA. SUBJECTS Data from 5288 volunteers who participated in the ARIC study were used for all analyses reported herein. RESULTS The study population was 62% male and 84 % white, mean age 53·5 (sd 5·7) years and mean BMI 26·2 (sd 4·6) kg/m2. A moderately high intake of dietary MUFA (10-15 % of total daily energy) was associated with a 10 % reduced risk of isolated IFG incidence, while a high intake of n-3 FA (>0·15 % of total daily energy) was associated with a 10 % increase in risk. Curiously, moderately high intake of n-6 PUFA (4-5 % of total daily energy) was associated with a 12 % reduction in IFG and IGT incidence. CONCLUSIONS MUFA, n-3 and n-6 FA contribute differently to the development of isolated IFG v. IFG with IGT; and their mechanism may be more complex than originally proposed.