Effects of carnosine and histidine-containing dipeptides on biomarkers of inflammation and oxidative stress: a systematic review and meta-analysis.

CONTEXT: Carnosine and histidine-containing dipeptides (HCDs) are suggested to have anti-inflammatory and antioxidative benefits, but their effects on circulating adipokines and inflammatory and oxidative stress biomarkers remain unclear. OBJECTIVES: The aim of the present systematic review and meta-analysis was to determine the impact of HCD supplementation on inflammatory and oxidative stress biomarkers. DATA SOURCES: A systematic search was performed on Medline via Ovid, Scopus, Embase, ISI Web of Science, and the Cochrane Library databases from inception to 25 January 2023. DATA EXTRACTION: Using relevant key words, trials investigating the effects of carnosine/HCD supplementation on markers of inflammation and oxidative stress, including C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), adiponectin, malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), total antioxidant capacity (TAC), and catalase (CAT) were identified. Meta-analyses were conducted using random-effects models to calculate the weighted mean differences (WMDs) and 95% confidence intervals (CIs). DATA ANALYSIS: A total of 9 trials comprising 350 participants were included in the present meta-analysis. Carnosine/HCD supplementation led to a significant reduction in CRP (WMD: -0.97 mg/L; 95% CI: -1.59, -0.36), TNF-α (WMD: -3.60 pg/mL; 95% CI: -7.03, -0.18), and MDA (WMD: -0.34 µmol/L; 95% CI: -0.56, -0.12) and an elevation in CAT (WMD: 4.48 U/mL; 95% CI: 2.43, 6.53) compared with placebo. In contrast, carnosine/HCD supplementation had no effect on IL-6, adiponectin, GSH, SOD, and TAC levels. CONCLUSION: Carnosine/HCD supplementation may reduce inflammatory and oxidative stress biomarkers, and potentially modulate the cardiometabolic risks associated with chronic low-grade inflammation and lipid peroxidation. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42017075354.

Disrupting future discounting: a commentary on an underutilised psychological approach for improving adherence to diet and physical activity interventions.

Non-communicable diseases (NCD) such as CVD and type 2 diabetes mellitus are major contributors to the burden of disease. NCD are largely driven by modifiable lifestyle factors including poor diet and insufficient physical activity, and consequently, prevention is a public health priority. Although diet and physical activity levels can be improved via lifestyle interventions, long-term adherence to such interventions remains low, which limits their effectiveness. Thus, it is critical to identify the underlying mechanisms that challenge uptake and adherence to such interventions. The current commentary discusses an important, but underexplored, psychological driver of poor adherence to lifestyle interventions, namely, future discounting, which describes the tendency to prefer smaller, short-term rewards over larger, long-term rewards. For example, in the nutrition domain, future discounting refers to valuing the immediate reward of excessive intake of energy-dense, nutrient-poor, discretionary foods high in salt, sugar, and saturated fat, and insufficient intake of low-energy, nutrient-dense, whole foods such as vegetables. Prominent theoretical models propose that excessive future discounting is a major contributor to the development of unhealthy lifestyle behaviours. Furthermore, a vast body of evidence suggests that future discounting plays a key role in risk of NCD. Thus, the evidence to date supports the idea that future discounting is an important multi-behaviour target for supporting lifestyle behaviour change; however, this approach has been largely neglected in preventive health efforts. Furthermore, this commentary discusses promising techniques (e.g. Episodic Future Thinking) for disrupting future discounting to promote improved adherence to lifestyle interventions aimed at reducing NCD risk.

The effects of probiotic and synbiotic supplementation on inflammation, oxidative stress, and circulating adiponectin and leptin concentration in subjects with prediabetes and type 2 diabetes mellitus: a GRADE-assessed systematic review, meta-analysis, and meta-regression of randomized clinical trials.

PURPOSE: Probiotics or synbiotics consumption have been suggested to reduce the risk of cardiovascular disease (CVD) through a decline in inflammation and oxidative stress, however, the results from studies are conflicting. This study filled this knowledge gap by evaluating randomized controlled trials (RCTs) investigating probiotics or synbiotics intake on adipokines, inflammation, and oxidative stress in patients with prediabetes and type-2 diabetes mellitus (T2DM). METHODS: We systematically did search up to March 2022 in PubMed/Medline, Scopus, ISI Web of Science, and Cochrane library. A random-effect model was applied to estimate the weighted mean difference (WMD) and 95% confidence interval (95% CI) for each outcome. RESULTS: A total of 32 RCTs were included in the meta-analysis. This intervention led to a significant decrease in levels of C-reactive protein (CRP) (WMD - 0.62 mg/l; 95% CI - 0.80, - 0.44; p < 0.001), tumor necrosis factor-α (TNF-α) (WMD - 0.27 pg/ml; 95% CI - 0.44, - 0.10; p = 0.002) and malondialdehyde (MDA) (WMD - 0.51 µmol/l; 95% CI - 0.73, - 0.30; p < 0.001), and also a significant increase in levels of glutathione (GSH) (WMD 69.80 µmol/l; 95% CI 33.65, 105.95; p < 0.001), total antioxidant capacity (TAC) (WMD 73.59 mmol/l; 95% CI 33.24, 113.95; p < 0.001) and nitric oxide (NO) (WMD 7.49 µmol/l; 95% CI 3.12, 11.86; p = 0.001), without significant alterations in interleukin-6 (IL-6) and adipokines levels. CONCLUSION: A consumption of probiotics or synbiotics could be a useful intervention to improve cardiometabolic outcomes through a reduced inflammation and oxidative stress in patients with prediabetes and T2DM.

Dietary Total Antioxidant Capacity and Odds of Breast Cancer: A Case-Control Study.

Breast cancer (BC) is the most frequently diagnosed female cancer worldwide. It has been shown that oxidative stress can contribute to cancer development. Therefore, we investigated the association between dietary total antioxidant capacity (TAC) and breast cancer risk in a case-control study. This study was conducted on 136 newly diagnosed breast cancer patients and 272 hospitalized controls in Tehran, Iran. Participant habitual diet was obtained using a 168-item validated food frequency questionnaire. Dietary TAC scores were computed using two different methods: the dietary ferric reducing antioxidant potential (FRAP) method and oxygen radical scavenging capacity (ORAC). The association between dietary TAC and breast cancer risk was estimated by logistic regression. The score of DTAC calculated by ORAC method was associated with lower odds of BC, especially among premenopausal women. However, this association was not significant after controlling potential confounders (ORAC: OR Q4-Q1 = 1.01, 95% CI = 0.42-2.44, p-trend = 0.96). Estimation of DTAC by FRAP method was not associated with the risk of BC (FRAP: OR Q4-Q1 = 1.04, 95% CI = 0.53-2.05, p-trend = 0.8). There were no association detected based on menopausal status. In this study, dietary TAC was not significantly related to the odds of breast cancer.

Associations between hyper-polypharmacy and potentially inappropriate prescribing with clinical and functional outcomes in older adults.

BACKGROUND: Hyper-polypharmacy and potentially inappropriate prescribing (PIP) are common among older inpatients. This study investigated associations between hyper-polypharmacy and PIP with clinical and functional outcomes in older adults at 3-months after hospital discharge. RESEARCH DESIGN AND METHOD: At discharge, prescribed medications were collected and PIPs, comprising potentially inappropriate medications (PIM) and potential prescribing omissions (PPO), were retrospectively identified using STOPP/START version 2. Outcomes were collected prospectively via telephone follow-up and audit. RESULTS: Data for 232 patients (mean age 80 years) were analyzed. PIP prevalence at discharge was 73.7% (PIMs 62.5%, PPOs 36.6%). Exposure to at least 1 PIM was associated with an increased occurrence of unplanned hospital readmission (adjusted odds ratio (AOR) 5.09; 95% CI 2.38─10.85), emergency department presentation (AOR 4.69; 95% CI 1.55─14.21) and the composite outcome (AOR 6.83; 95% CI 3.20─14.57). The number rather than the presence of PIMs was significantly associated with increased dependency in at least 1 activity of daily living (ADL) (AOR 2.31; 95% CI 1.08─4.20). Increased PIP use was associated with mortality (AOR 1.45; 95% CI 1.05─1.99). CONCLUSION: PIPs overall, and PIMs specifically, were frequent in older adults at hospital discharge, and were associated with increased re-hospitalizations and dependence in ADLs at 3-months post-discharge.

Novel Lipidomic Signature Associated With Metabolic Risk in Women With and Without Polycystic Ovary Syndrome.

CONTEXT: Dyslipidemia is a feature of polycystic ovary syndrome (PCOS) and may augment metabolic dysfunction in this population. OBJECTIVE: Using comprehensive lipidomic profiling and gold-standard metabolic measures, we examined whether distinct lipid biomarkers were associated with metabolic risk in women with and without PCOS. METHODS: Using preexisting data and biobanked samples from 76 women (n = 42 with PCOS), we profiled > 700 lipid species by mass spectrometry. Lipids were compared between women with and without PCOS and correlated with direct measures of adiposity (dual x-ray absorptiometry and computed tomography) and insulin sensitivity (hyperinsulinemic-euglycemic clamp), as well as fasting insulin, HbA1c, and hormonal parameters (luteinizing and follicle-stimulating hormones; total and free testosterone; sex hormone-binding globulin [SHBG]; and free androgen index [FAI]). Multivariable linear regression was used with correction for multiple testing. RESULTS: Despite finding no differences by PCOS status, lysophosphatidylinositol (LPI) species esterified with an 18:0 fatty acid were the strongest lipid species associated with all the metabolic risk factors measured in women with and without PCOS. Across the cohort, higher concentrations of LPI(18:0) and lower concentrations of lipids containing docosahexaenoic acid (DHA, 22:6) n-3 polyunsaturated fatty acids were associated with higher adiposity, insulin resistance, fasting insulin, HbA1c and FAI, and lower SHBG. CONCLUSION: Our data indicate that a distinct lipidomic signature comprising high LPI(18:0) and low DHA-containing lipids are associated with key metabolic risk factors that cluster in PCOS, independent of PCOS status. Prospective studies are needed to corroborate these findings in larger cohorts of women with varying PCOS phenotypes.

Association between Diet Quality Indices and Incidence of Type 2 Diabetes in the Melbourne Collaborative Cohort Study.

Type 2 diabetes mellitus is a common condition whose incidence is increasing worldwide, and for which obesity and diet are important risk factors. The aim of this study was to assess the association of three diet quality scores with diabetes risk and how much of the association was mediated through body size. The Melbourne Collaborative Cohort Study recruited 41,513 men and women aged 40-69 years during 1990-1994. At baseline, data were collected on lifestyle and diet, anthropometric measures were performed. Incident diabetes was assessed by self-report at follow-up surveys in 1994-1998 and 2003-2007. The associations between the dietary inflammatory index (DII®), Mediterranean Diet Score (MDS) and the Alternative Healthy Eating Index-2010 and incident diabetes were assessed using Poisson regression, adjusting for age, sex, physical activity, smoking, alcohol consumption, socio-economic status (area based) and family history of diabetes. Data from 39,185 participants were included in the analysis and 1989 cases of diabetes were identified. Both DII and AHEI-2010 were associated with diabetes incidence, but MDS was not. In the top quintile of DII (most pro-inflammatory) vs. the least inflammatory quintile IRR was 1.49 95% CI (1.30, 1.72), p trend across quintiles <0.001. For AHEI-2010 the IRR was 0.67 (0.58, 0.78), p trend <0.001 for the healthiest vs. the least healthy quintile. Mediation analysis indicated that body size (body mass index/waist to hip ratio) mediated 35-48% of the association with incident diabetes for the AHEI and DII. Healthier diets may reduce risk of diabetes both by reducing weight gain and other mechanisms such as reducing inflammation.

Use of carnosine in the prevention of cardiometabolic risk factors in overweight and obese individuals: study protocol for a randomised, double-blind placebo-controlled trial.

INTRODUCTION: Carnosine, an over the counter food supplement, has been shown to improve glucose metabolism as well as cardiovascular risk factors in animal and human studies through its anti-inflammatory, antioxidative, antiglycating and chelating properties. The aim of this study is to establish if carnosine supplementation improves obesity, insulin sensitivity, insulin secretion, cardiovascular risk factors including arterial stiffness and endothelial function, and other risk factors related to diabetes and cardiovascular disease in the overweight and obese population. METHODS AND ANALYSIS: Fifty participants will be recruited to be enrolled in a double-blind randomised controlled trial. Eligible participants with a body mass index (BMI) between 25 and 40 kg/m2 will be randomly assigned to the intervention or placebo group. Following a medical review and oral glucose tolerance test to check eligibility, participants will then undergo testing. At baseline, participants will have anthropometric measurements (BMI, dual X-ray absorptiometry and peripheral quantitative CT scan), measurements of glucose metabolism (oral glucose tolerance test, intravenous glucose tolerance test and euglycaemic hyperinsulinaemic clamp), cardiovascular measurements (central blood pressure, endothelial function and arterial stiffness), a muscle and fat biopsy, physical activity measurement, liver fibroscan, cognitive function and questionnaires to assess dietary habits, sleep quality, depression, and quality of life. Following baseline assessments, participants will be randomised to either 2 g carnosine or placebo for 15 weeks. In the 15th week, all assessments will be repeated. The preplanned outcome metric is the change between baseline and follow-up measures. ETHICS AND DISSEMINATION: This study is approved by the Human Research Ethics Committee of Monash Health and Monash University, Australia. TRIAL REGISTRATION NUMBER: NCT02686996.

Anti-Cancer Effects of Carnosine-A Dipeptide Molecule.

BACKGROUND: Carnosine is a dipeptide molecule (ß-alanyl-l-histidine) with anti-inflammatory, antioxidant, anti-glycation, and chelating properties. It is used in exercise physiology as a food supplement to increase performance; however, in vitro evidence suggests that carnosine may exhibit anti-cancer properties. METHODS: In this study, we investigated the effect of carnosine on breast, ovarian, colon, and leukemic cancer cell proliferation. We further examined U937 promonocytic, human myeloid leukemia cell phenotype, gene expression, and cytokine secretion to determine if these are linked to carnosine's anti-proliferative properties. RESULTS: Carnosine (1) inhibits breast, ovarian, colon, and leukemic cancer cell proliferation; (2) upregulates expression of pro-inflammatory molecules; (3) modulates cytokine secretion; and (4) alters U937 differentiation and phenotype. CONCLUSION: These effects may have implications for a role for carnosine in anti-cancer therapy.

Diet scores and prediction of general and abdominal obesity in the Melbourne collaborative cohort study.

OBJECTIVE: To ascertain which of the Alternative Healthy Eating Index (AHEI) 2010, Dietary Inflammatory Index (DII®) and Mediterranean Diet Score (MDS) best predicted BMI and waist-to-hip circumference ratio (WHR). DESIGN: Body size was measured at baseline (1990-1994) and in 2003-2007. Diet was assessed at baseline using a FFQ, along with age, sex, socio-economic status, smoking, alcohol drinking, physical activity and country of birth. Regression coefficients and 95 % CI for the association of baseline dietary scores with follow-up BMI and WHR were generated using multivariable linear regression, adjusting for baseline body size, confounders and energy intake. SETTING: Population-based cohort in Melbourne, Australia. PARTICIPANTS: Included were data from 11 030 men and 16 774 women aged 40-69 years at baseline. RESULTS: Median (IQR) follow-up was 11·6 (10·7-12·8) years. BMI and WHR at follow-up were associated with baseline DII® (Q5 v. Q1 (BMI 0·41, 95 % CI 0·21, 0·61) and WHR 0·009, 95 % CI 0·006, 0·013)) and AHEI (Q5 v. Q1 (BMI -0·51, 95 % CI -0·68, -0·35) and WHR -0·011, 95 % CI -0·013, -0·008)). WHR, but not BMI, at follow-up was associated with baseline MDS (Group 3 most Mediterranean v. G1 (BMI -0·05, 95 % CI -0·23, 0·13) and WHR -0·004, 95 % CI -0·007, -0·001)). Based on Akaike's Information Criterion and Bayesian Information Criterion statistics, AHEI was a stronger predictor of body size than the other diet scores. CONCLUSIONS: Poor quality or pro-inflammatory diets predicted overall and central obesity. The AHEI may provide the best way to assess the obesogenic potential of diet.

The Relationship between Vitamin D Metabolites and Androgens in Women with Polycystic Ovary Syndrome.

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among women of reproductive age, with hyperandrogenism present in up to 90% of affected women. Some evidence suggests a link between vitamin D deficiency and PCOS features via insulin resistance and inflammation. Our aim was to explore the relationship between biochemical markers of vitamin D status and androgens in women with PCOS. This cross-sectional study used bio-banked samples from 46 pre-menopausal women with PCOS (mean ± SD: age 30 ± 6 years; BMI 29 ± 6 kg/m2). We measured 25-hydroxyvitamin D (25[OH]D), vitamin D-binding protein (DBP), total testosterone, sex hormone-binding globulin (SHBG), and calculated the free androgen index (FAI) and bioavailable and free 25(OH)D. Fasting glucose and insulin were used to calculate the homeostatic model assessment of insulin resistance (HOMA-IR) and body fat percentage was determined via dual energy x-ray absorptiometry. High-sensitivity C-reactive protein (hs-CRP) was measured as a marker of inflammation. DBP was positively associated with total 25(OH)D and expectedly, negatively associated with free 25(OH)D. There were no associations between vitamin D metabolites and total testosterone, SHBG or FAI, even after adjusting for age, body fat percentage, HOMA-IR and hs-CRP. We found no associations between vitamin D metabolites and androgens in women with PCOS. Studies that have identified a vitamin D-androgen link have largely relied on methodology with numerous pitfalls; future studies should exclusively use gold-standard measures to confirm these findings in this population.

Are Lifestyle Interventions to Reduce Excessive Gestational Weight Gain Cost Effective? A Systematic Review.

PURPOSE OF REVIEW: Lifestyle interventions (such as diet and physical activity) successfully limit excessive gestational weight gain and can reduce some adverse maternal events; however, benefit is variable and cost-effectiveness remains unclear. We aimed to review published cost-effectiveness analyses of lifestyle interventions compared with usual care on clinically relevant outcome measures. Five international and six grey-literature databases were searched from 2007 to 2018. Articles were assessed for quality of reporting. Data were extracted from healthcare and societal perspectives. Costs were adapted to the common currencies of Australia and the United Kingdom by adjusting for resource utilization, healthcare purchase price and changes in costs over time. Included studies were economic analyses of lifestyle interventions aiming to limit weight-gain during pregnancy and/or reduce risk of gestational diabetes, for women with a BMI of 25 or greater in pre- or early-pregnancy. RECENT FINDINGS: Of the 538 articles identified, six were retained for review: one modelling study and five studies in which an economic analysis was performed alongside a randomized-controlled trial. Outcome measures included infant birth-weight, fasting glucose, insulin resistance, gestational weight-gain, infant respiratory distress syndrome, perceived health, cost per case of adverse outcome avoided and quality-adjusted life years (QALYs). Interventions were cost-effective in only one study. Although many studies have investigated the efficacy of lifestyle interventions in pregnancy, few have included cost-effectiveness analyses. Where cost-effectiveness studies were undertaken, results were inconsistent. Secondary meta-analysis, taxonomy and framework research is now required to determine the effective components of lifestyle interventions and to guide future cost-effectiveness analyses.

Plasma Phospholipids with Long-Chain Polyunsaturated Fatty Acids and Dihydroceramides at the Crossroads of Iron Stores and Insulin Resistance.

SCOPE: Iron plays an important role in the pathogenesis of insulin resistance (IR) and type 2 diabetes. Recent studies suggest a role of specific lipids in the induction of IR, but the potential relationships between iron and lipid metabolites in relation to IR have not been explored. Therefore, the aim of the study is to evaluate the association among iron, IR, and the lipidome. METHODS AND RESULTS: The plasma lipidome, IR, parameters of iron metabolism, and several cytokines and adipokines in 65 overweight/obese participants are measured. Measurements of IR correlate positively with ferritin, a measure of iron storage (r = 0.35, p = 0.005), and negatively with adiponectin (r = -0.30, p = 0.02). The serum ferritin/adiponectin ratio has a stronger association with IR (r = 0.41, p < 0.001). From multivariate analyses adjusted for age, sex, and BMI, several phospholipids containing long chain polyunsaturated fatty acids (PUFA) with 20-22 carbons (phosphatidylcholines, phosphatidylethanolamines, phosphatidylinositols, and a phosphatidylserine), are positively associated with ferritin and the ferritin/adiponectin ratio. Two dihydroceramides (Cer(18:0/22:0), Cer(18:0/24:0)) and several diglycerides and triglycerides, mainly comprised of C14:0, C16:0, C18:0, C18:1, and C18:2, also have positive correlations with ferritin and the ferritin/adiponectin ratio. CONCLUSIONS: The positive associations between these lipid species and ferritin or the ferritin/adiponectin ratio suggest a potential crosstalk between iron and lipid metabolism in obesity and IR.

Systematic Review of the Effects of Ultraviolet Radiation on Markers of Metabolic Dysfunction.

Emerging findings suggest that exposure to ultraviolet wavelengths of sunlight modulates metabolic function. Here we review the metabolic effects of exposure to ultraviolet radiation (UVR), focusing on the effects of phototherapies (that administer UVR), and advice to increase sun exposure in individuals enrolled in clinical trials and intervention studies. We identified 25 studies in which the effects of UVR on metabolic outcomes were examined, including: narrowband ultraviolet B phototherapy (nbUVB, n = 12); psoralen ultraviolet A phototherapy (n = 4); other types of UVR phototherapy (n = 5); and sun exposure advice (n = 5). Most studies recruited a small number of participants (≤100), who were middle-aged individuals undergoing treatment for psoriasis flare, with phototherapy or sun exposure advice administered for ≤12 weeks. Data obtained at baseline were usually compared with an endpoint following treatment with UVR, for a limited number of outcomes. There were few studies in which markers of glucose metabolism were assessed, with some beneficial effects of sun exposure (but not phototherapy) reported. LDL-cholesterol levels were lower in individuals receiving sun exposure advice, while treatment with nbUVB reduced blood concentrations of inflammatory markers (C-reactive protein and interleukin-6). Future studies should focus on determining whether the effects of these interventions change with time, and if they are dependent on the source of UVR (i.e. phototherapy or sun exposure) and wavelength(s) of light administered. Furthermore, studies need to measure a variety of (clinical) markers of glucose metabolism, adiposity and inflammation, control for factors such as skin type and sex, and stratify participants for metabolic disease diagnosis.

Increased Inflammation and Cardiometabolic Risk in Individuals with Low AMY1 Copy Numbers.

Lower copy number variations (CNVs) in the salivary amylase gene (AMY1) have been associated with obesity and insulin resistance; however, the relationship between AMY1 and cardiometabolic risk has not been fully elucidated. Using gold-standard measures, we aimed to examine whether AMY1 CNVs are associated with cardiometabolic risk factors in an overweight or obese, otherwise healthy population. Fifty-seven adults (58% male) aged 31.17 ± 8.44 years with a body mass index (BMI) ≥25 kg/m² were included in the study. We measured AMY1 CNVs (qPCR); anthropometry (BMI; body composition by dual-energy X-ray absorptiometry); cardiovascular parameters (blood pressure, serum lipids by ELISA); insulin sensitivity (hyperinsulinaemic⁻euglycaemic clamp), insulin secretion (intravenous glucose tolerance test), and serum inflammation markers (multiplex assays). Based on previous studies and median values, participants were divided into low (≤4) and high (>4) AMY1 CNV groups. Low AMY1 carriers (n = 29) had a higher fat mass (40.76 ± 12.11 versus 33.33 ± 8.50 kg, p = 0.009) and LDL-cholesterol (3.27 ± 0.80 versus 2.87 ± 0.69 mmol/L, p = 0.038), and higher serum levels of interleukin [IL]-6, IL-1ß, tumour necrosis factor-alpha and monocyte chemoattractant protein-1 (MCP-1) (all p < 0.05) compared with high AMY1 carriers (n = 28), but there were no differences in glycaemic measures, including insulin sensitivity or secretion (all p > 0.1). Except for MCP-1, the results remained significant in multivariable models adjusted for age, sex, and fat mass (all p < 0.05). Our findings suggest that low AMY1 CNVs are associated with increased cardiovascular disease risk and inflammation, but not glucose metabolism, in overweight or obese adults.

Role of serum biomarkers to optimise a validated clinical risk prediction tool for gestational diabetes.

BACKGROUND: Clinical risk prediction tools for gestational diabetes (GDM) may be enhanced by measuring biomarkers in early pregnancy. AIM: To evaluate a two-step GDM risk prediction tool incorporating fasting glucose (FG) and serum biomarkers in early pregnancy. MATERIALS AND METHODS: High molecular weight (HMW) adiponectin, omentin-1 and interleukin-6 (IL-6) were measured at 12-15 weeks gestation in women with high risk of GDM from a randomised trial using a clinical risk prediction tool. GDM diagnosis (24-28 weeks) was evaluated using 1998 Australian Diabetes in Pregnancy (ADIPS) criteria and newer International Association of the Diabetes and Pregnancy Study Groups (IADPSG) criteria. Associations between biomarkers and development of GDM were examined using multivariable regression analysis. Area under the receiver-operator curve (AUC), sensitivity and specificity were calculated to determine classification ability of each model compared to FG and maternal characteristics. RESULTS: HMW adiponectin improved prediction of ADIPS GDM (AUC 0.85, sensitivity 50%, specificity 96.2%, P = 0.04), compared to FG and maternal factors (0.78, 35% and, 98.1%, respectively). HMW adiponectin <1.53 µg/mL further improved the model (AUC 0.87, sensitivity 75%, specificity 88.2%, P = 0.01). HMW adiponectin did not improve prediction of IADPSG GDM (AUC 0.84, sensitivity 64%, specificity 97.9%, P = 0.22) compared to FG and maternal factors (0.79, 56%, 93.8%). Omentin-1 and IL-6 did not significantly improve classification ability for GDM. CONCLUSIONS: A two-step approach combining FG and HMW adiponectin to a validated clinical risk prediction tool improved sensitivity and predictive ability for ADIPS GDM. Further research is required to enhance GDM prediction using IADPSG criteria for application in clinical practice.

Brown adipose tissue thermogenesis in polycystic ovary syndrome.

OBJECTIVE: Polycystic ovary syndrome (PCOS) is associated with increased obesity with a greater propensity to weight gain and a lack of sustainable lifestyle interventions. Altered brown adipose tissue (BAT) thermogenesis is a potential contributor to obesity in PCOS. BAT activity and modulation have not been studied in PCOS. This observational study explored BAT thermogenesis and its associations in women with and without PCOS. PARTICIPANTS AND METHODS: Cutaneous temperature was recorded from supraclavicular (indicator of BAT activity) and upper arm regions using dataloggers (SubCue, Calgary, Canada) in a cross-sectional substudy, nested within a randomized control trial, of community-recruited premenopausal women with (n = 47, Rotterdam diagnostic criteria) and without (n = 11) PCOS. RESULTS: Complete temperature data were available in 44 PCOS (mean age: 30.0 ± 6.2, mean BMI: 29.3 ± 5.5) and 11 non-PCOS (mean age: 33.0 ± 7.0, mean BMI: 25 ± 3) women. Women with PCOS had lower supraclavicular skin temperature compared to controls overall (33.9 ± 0.7 vs 34.5 ± 1, P < 0.05) and during sleep (34.5 ± 0.6 vs 35.2 ± 0.9, P < 0.001). In the PCOS group, supraclavicular skin temperature overall and over sleep and waking hours correlated inversely with testosterone (r = -0.41 P < 0.05, r = -0.485 P < 0.01 and r = -0.450 P < 0.01 respectively). Testosterone levels explained approximately 15%, 30% and 20% of the variability in supraclavicular skin temperature overall and over sleep and waking hours in women with PCOS, respectively. CONCLUSION: Women with PCOS have lower BAT activity compared to controls. BAT thermogenesis is negatively associated with androgen levels in PCOS.

Carnosine Supplementation Improves Serum Resistin Concentrations in Overweight or Obese Otherwise Healthy Adults: A Pilot Randomized Trial.

Adipokines play an important role in the regulation of glucose metabolism. We have previously shown that carnosine supplementation in overweight or obese non-diabetic individuals improves glucose metabolism but does not change adiponectin concentrations. However, its effect on other adipokines has not been investigated. Herein we further determined the effect of carnosine supplementation on serum adipsin, resistin and leptin. Twenty-two overweight or obese otherwise healthy adults were randomly assigned to receive either 2 g of carnosine (n = 13) or identically looking placebo (n = 9) for 12 weeks. Serum adipsin, leptin and resistin were analyzed using a bead-based multiplex assay. Carnosine supplementation decreased serum resistin concentrations compared to placebo (mean change from baseline: -35 ± 83 carnosine vs. 35 ± 55 ng/mL placebo, p = 0.04). There was a trend for a reduction in serum leptin concentrations after carnosine supplementation (-76 ± 165 ng/mL carnosine vs. 20 ± 28 ng/mL placebo, p = 0.06). The changes in leptin and resistin concentrations were inversely related to the change in concentration for urinary carnosine (r = -0.72, p = 0.0002; r = -0.67, p = 0.0009, respectively), carnosine-propanal (r = -0.56, p = 0.005; r = -0.63, p = 0.001, respectively) and carnosine-propanol (r = -0.61, p = 0.002; r = -0.60, p = 0.002, respectively). There were no differences between groups in change in adipsin concentrations. Our findings show carnosine supplementation may normalize some, but not all, of the serum adipokine concentrations involved in glucose metabolism, in overweight and obese individuals. Further clinical trials with larger samples are needed to confirm these results.

Inter-related effects of insulin resistance, hyperandrogenism, sympathetic dysfunction and chronic inflammation in PCOS.

OBJECTIVE: Insulin resistance, hyperandrogenism, sympathetic dysfunction and chronic low-grade inflammation may act together in a vicious cycle in the pathophysiology of PCOS. However, the inter-relationships of these components are not fully understood. We aimed to study these mechanisms in the pathophysiology of PCOS. PARTICIPANTS AND METHODS: Premenopausal women with PCOS (Rotterdam diagnostic criteria) and without PCOS were recruited from a community setting into a cross-sectional substudy within a randomized control trial. Insulin resistance (fasting insulin and glucose), hyperandrogenism (testosterone, sex hormone-binding globulin [SHBG] and Free Androgen Index [FAI]), muscle sympathetic nerve activity (MSNA) and markers of chronic low-grade inflammation (high sensitivity C-reactive protein [hs-CRP] and high molecular weight adiponectin [HMW-adiponectin]) were measured. RESULTS: Forty-nine women with PCOS (mean age 30 ± 6 mean BMI 29 ± 5) and 23 controls (mean age 29 ± 8 mean BMI 33 ± 7) with included in this analysis. MSNA and testosterone level were most significantly associated with PCOS status, after adjustment for age and BMI. In women with PCOS, markers of sympathetic activity correlated inversely with HMW-adiponectin and HMW-adiponectin correlated inversely with FAI. Testosterone and FAI both correlated positively with insulin resistance in women PCOS. CONCLUSION: Sympathetic dysfunction and hyperandrogenism are significantly associated with PCOS. Chronic low-grade inflammation potentially mediates the effect of sympathetic dysfunction on hyperandrogenism and insulin resistance.