The Effects of the Mediterranean Diet on Health and Gut Microbiota.

The Mediterranean Diet (MD) is plant-based and consists of multiple daily portions of vegetables, fruit, cereals, and olive oil. Although there are challenges with isolating the MD from the typical Mediterranean lifestyle and culture (including prolonged 'social' meals and siestas), much evidence supports the health benefits of the MD that include improved longevity, reduced metabolic risk of Diabetes Mellitus, obesity, and Metabolic Syndrome, reduced risk of malignancy and cardiovascular disease, and improved cognitive function. The MD is also associated with characteristic modifications to gut microbiota, mediated through its constituent parts (primarily dietary fibres, extra virgin olive oil, and polyunsaturated fatty acids [including ω-3]). These include enhanced growth of species that produce short-chain fatty acids (butyrate), such as Clostridium leptum and Eubacterium rectale, enhanced growth of Bifidobacteria, Bacteroides, and Faecalibacterium prausnitzii species, and reduced growth of Firmicutes and Blautia species. Such changes in gut microbiota are known to be associated favourably with inflammatory and oxidative status, propensity for malignancy and overall metabolic health. A key challenge for the future is to explore the extent to which the health benefits of the MD are mediated by such changes to gut microbiota. The MD confers both health and environmental benefits. Adoption of the MD should perhaps be encouraged and facilitated more generally and not just restricted to populations from Mediterranean regions. However, there are key challenges to this approach that include limited perennial availability of the constituent parts of the MD in some non-Mediterranean regions, intolerability of a high-fibre diet for some people, and potential cultural disconnects that juxtapose some traditional (including Western) diets with the MD.

More than skin-deep: visceral fat is strongly associated with disease activity, function and metabolic indices in psoriatic disease.

OBJECTIVE: To compare body composition between patients with psoriatic disease (PsD), including cutaneous psoriasis (PsO) and psoriatic arthritis (PsA), and controls, and to explore associations between disease activity and measures of function and metabolic derangement. METHODS: Body composition was assessed by air displacement plethysmography (ADP) and MRI-derived fat segmentation using an automated pipeline (FatSegNet). Function was assessed by Health Assessment Questionnaire (HAQ) and metabolic status by fasting lipid profile, insulin and adiponectin. Active and inactive PsO and PsA were defined by body surface area (BSA) and Psoriasis Area Severity Index (PASI) and minimal disease activity (MDA), respectively. RESULTS: Thirty patients (median disease duration 15 years; median age 52 years) and 30 BMI-matched controls were enrolled. Compared with controls, all MRI-derived body composition parameters-whole-body volume, subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), abdominal adipose tissue (AAT), VAT/AAT and VAT/SAT-were higher in the PsD group, specifically, those with active disease. Body mass, body fat, whole-body volume and whole-body VAT were correlated with higher triglycerides, cholesterol:HDL (high-density lipoprotein), insulin resistance and lower adiponectin as well as higher HAQ and lower MDA. CONCLUSIONS: In this pilot study, patients with PsD revealed excessive total adipose tissue and a greater volume of metabolically unfavourable ectopic fat, including VAT, compared with BMI-matched controls, which also correlated with HAQ, disease activity and overall dysmetabolism. We also provide the first evidence in patients with PsD for the clinical application of FatSegNet: a novel, automated and rapid deep learning pipeline for providing accurate MRI-based measurement of fat segmentation. Our findings suggest the need for a more integrated approach to the management of PsD, which considers both the metabolic and inflammatory burden of disease. More specifically, visceral fat is a surrogate marker of uncontrolled PsD and may be an important future target for both pharmacological and lifestyle interventions.

Acute iv CRH administration significantly increases serum active ghrelin in postmenopausal PCOS women compared to postmenopausal controls.

PURPOSE: In women with Polycystic Ovarian Syndrome (PCOS), an increased risk of disordered eating has been described. There is growing interest regarding a possible interconnection between psychological states and increased appetite in women with PCOS. Acute stress is characterized by increased Corticotropin Releasing Hormone (CRH) secretion. The aim was to estimate the ghrelin concentrations during CRH test. METHODS: Twenty postmenopausal women with PCOS and twenty age- and BMI- matched postmenopausal control women were recruited at Aretaieion University Hospital. In the morning (9 am) all subjects had anthropometric measurements (weight, height, waist circumference) and a fasting sample for hormonal measurements. An intravenous (iv) CRH stimulation test conducted over 1 min. Serum active ghrelin levels were measured at 0, 15, 30, 60, 90, 120 min after iv CRH administration. RESULTS: The postmenopausal PCOS group had a higher waist circumference compared to postmenopausal controls. Active ghrelin concentrations increased significantly from 0 to 15 min, to 30 min, to 60 min, to 90 min and then decreased to 120 min. However, within the postmenopausal control group there were no significant changes in serum active ghrelin levels. Serum active ghrelin concentrations were significantly greater in the postmenopausal control group at 0, 15 and 120 min compared to the postmenopausal PCOS group. At 90 min active ghrelin concentrations were significantly greater in the postmenopausal PCOS group. Delta Area Under the Curve of active ghrelin (ΔAUCghr) was significantly greater in the postmenopausal PCOS group compared to controls. CONCLUSIONS: In postmenopausal PCOS, but not in postmenopausal controls, iv CRH administration induces increased serum active ghrelin secretion, suggesting a possible anti-stress adaptive mechanism. An increase in serum active ghrelin may induce hunger as a side-effect of this presumed adaptive mechanism.

Designer GLP1 poly-agonist peptides in the management of diabesity.

INTRODUCTION: To date, the 21st Century has witnessed key developments in the management of diabesity (a conflation of obesity and Type 2 Diabetes Mellitus [T2D]), including Glucagon Like Peptide 1 (GLP1) receptor agonist therapies, and recently the 'designer' GLP1 Poly-agonist Peptides (GLP1PPs). AREAS COVERED: A PubMed search of published data on the GLP1PP class of therapies was conducted. The gut-brain axis forms complex multi-directional interlinks that include autonomic nervous signaling, components of the gut microbiota (including metabolic by-products and gram-negative cell wall components [e.g. endotoxinaemia]), and incretin hormones that are secreted from the gut in response to the ingestion of nutrients. The development of dual-incretin agonist therapies includes combinations of the GLP1 peptide with Glucose-dependent Insulinotropic Polypeptide (GIP), Glucagon (Gcg), Cholecystokinin (CCK), Peptide YY (PYY), and Glucagon-Like Peptide 2 (GLP2). Triple incretin agonist therapies are also under development. EXPERT OPINION: At the dawn of a new era in the therapeutic management of diabesity, the designer GLP1PP class holds great promise, with each novel combination building on a preexisting palimpsest of clinical data and insights. Future innovations of the GLP1PP class will likely enable medically induced weight loss and glycemic control in diabesity to rival or even out-perform those resulting from bariatric surgery.

Childhood, adolescent, and adulthood adiposity are associated with risk of PCOS: a Mendelian randomization study with meta-analysis.

STUDY QUESTION: What is the influence of body composition during childhood, adolescence, and adulthood, as well as metabolic parameters, on incident polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: Excess body fat, even during childhood/adolescence, and metabolic parameters, suggestive of hyperinsulinaemia/insulin resistance, significantly impact the risk of PCOS in a linear fashion. WHAT IS KNOWN ALREADY: Observational and Mendelian randomization (MR) data have demonstrated an association between adulthood overweight/obesity and development of PCOS. However, the contribution of body composition in childhood/adolescence to incident PCOS is unclear, as is the influence of childhood overweight/obesity. STUDY DESIGN, SIZE, DURATION: We conducted a systematic review and meta-analysis and integrated our results with a previously published systematic review. Two blinded investigators screened abstracts published between November 2010 and May 2021. Furthermore, we incorporated summary statistics from genome-wide association study (GWAS) data in subjects of European ancestry. Adult overweight was defined as BMI ≥ 25 kg/m2 and obesity as BMI ≥ 30 kg/m2; in Asian subjects, overweight was defined as BMI ≥ 23 kg/m2 and obesity as BMI ≥ 25 kg/m2. PARTICIPANTS/MATERIALS, SETTING, METHODS: We utilized meta-analysis and MR together to allow synthesis of genetic and observational data. For the systematic review, the search revealed 71 studies, of which 63 were included in meta-analysis by calculating odds ratios (ORs) using the random-effects model. Furthermore, we conducted a two-sample MR study of GWAS data to determine the impact of childhood and adult body size (defined categorically by BMI and childhood body size proportions), abnormal body composition and metabolic parameters (higher fasting serum insulin or lower sex hormone-binding globulin (SHBG) concentration) on the odds of incident PCOS via the inverse-variance weighted method. MAIN RESULTS AND THE ROLE OF CHANCE: Significant associations were shown between body composition and PCOS incidence. From the systematic review/meta-analysis, women with overweight (OR 3.80, 2.87-5.03), obesity (OR 4.99, 3.74-6.67), and central obesity (OR 2.93, 2.08-4.12) had increased odds of PCOS. For adolescents with overweight and/or obesity, the PCOS odds were greater than for adults. From MR, for every standard deviation increase in BMI (4.8 kg/m2), the odds of PCOS increased by 2.76 (2.27-3.35). Childhood body size had an independent effect on PCOS odds after adjusting for adult body size (OR: 2.56, 1.57-4.20). Genetically determined body fat percentage (OR 3.05, 2.24-4.15), whole body fat mass (OR 2.53, 2.04-3.14), fasting serum insulin (OR 6.98, 2.02-24.13), and SHBG concentration (OR 0.74, 0.64-0.87) were all significantly associated with PCOS in a linear relation. LIMITATIONS, REASONS FOR CAUTION: The meta-analysis included studies which were cross-sectional and retrospective, limiting our ability to determine causality. MR was limited by interrogating subjects only of European ancestry and including cases classified by either self-diagnosis or diagnostic criteria. WIDER IMPLICATIONS OF THE FINDINGS: Our study demonstrates for the first time a critical role of the impact of excess childhood/adolescent adiposity on the pathophysiology of adult PCOS. Our results, driven by genetically determined childhood/adolescent body composition, higher BMI, hyperinsulinaemia, and lower SHBG, clearly favour obesity driving the metabolic, but not reproductive, PCOS phenotype. Overall, effective weight maintenance, even from the early years, is likely to reduce the risk of this reproductive endocrine disorder. STUDY FUNDING/COMPETING INTEREST(S): S.S.Z. was funded by a National Institute for Health and Care Research (NIHR) Academic Clinical Lectureship. U.A. is chair of the NIHR Steering Committee Trial-CASSANDRA-DN. No other authors declare any sources of funding or relevant conflicts of interest. The authors declare that the research was conducted in the absence of any commercial or financial relations that could be construed as a potential conflict of interest. TRIAL REGISTRATION NUMBER: N/A.

Implications of Resveratrol in Obesity and Insulin Resistance: A State-of-the-Art Review.

Background: Resveratrol is a polyphenol chemical that naturally occurs in many plant-based dietary products, most notably, red wine. Discovered in 1939, widespread interest in the potential health benefits of resveratrol emerged in the 1970s in response to epidemiological data on the cardioprotective effects of wine. Objective: To explore the background of resveratrol (including its origins, stability, and metabolism), the metabolic effects of resveratrol and its mechanisms of action, and a potential future role of dietary resveratrol in the lifestyle management of obesity. Data sources: We performed a narrative review, based on relevant articles written in English from a Pubmed search, using the following search terms: "resveratrol", "obesity", "Diabetes Mellitus", and "insulin sensitivity". Results: Following its ingestion, resveratrol undergoes extensive metabolism. This includes conjugation (with sulfate and glucuronate) within enterocytes, hydrolyzation and reduction within the gut through the action of the microbiota (with the formation of metabolites such as dihydroresveratrol), and enterohepatic circulation via the bile. Ex vivo studies on adipose tissue reveal that resveratrol inhibits adipogenesis and prevents the accumulation of triglycerides through effects on the expression of Peroxisome Proliferator-activated Receptor γ (PPARγ) and sirtuin 1, respectively. Furthermore, resveratrol induces anti-inflammatory effects, supported by data from animal-based studies. Limited data from human-based studies reveal that resveratrol improves insulin sensitivity and fasting glucose levels in patients with Type 2 Diabetes Mellitus and may improve inflammatory status in human obesity. Although numerous mechanisms may underlie the metabolic benefits of resveratrol, evidence supports a role in its interaction with the gut microbiota and modulation of protein targets, including sirtuins and proteins related to nitric oxide, insulin, and nuclear hormone receptors (such as PPARγ). Conclusions: Despite much interest, there remain important unanswered questions regarding its optimal dosage (and how this may differ between and within individuals), and possible benefits within the general population, including the potential for weight-loss and improved metabolic function. Future studies should properly address these important questions before we can advocate the widespread adoption of dietary resveratrol supplementation.

Vitamin D Levels as an Important Predictor for Type 2 Diabetes Mellitus and Weight Regain Post-Sleeve Gastrectomy.

Weight Loss Surgery (WLS), including sleeve-gastrectomy (SG), results in significant weight loss and improved metabolic health in severe obesity (BMI ≥ 35 kg/m2). Previous studies suggest post-operative health benefits are impacted by nutrient deficiencies, such as Vitamin D (25(OH)D) deficiency, while it is currently unknown whether nutrient levels may actually predict post-surgery outcomes. As such, this study investigated whether 25(OH)D levels could predict metabolic improvements in patients who underwent SG. Patients with severe obesity (n = 309; 75% female) undergoing SG participated in this ethics-approved, non-randomized retrospective cohort study. Anthropometry, clinical data, 25(OH)D levels and serum markers were collected at baseline, 6-, 12- and 18-months post-surgery. SG surgery resulted in significant improvements in metabolic health at 6- and 12-months post-surgery compared with baseline, as expected. Patients with higher baseline 25(OH)D had significantly lower HbA1c levels post-surgery (p < 0.01) and better post-surgical T2DM outcomes, including reduced weight regain (p < 0.05). Further analysis revealed that baseline 25(OH)D could predict HbA1c levels, weight regain and T2DM remission one-year post-surgery, accounting for 7.5% of HbA1c divergence (p < 0.01). These data highlight that higher circulating 25(OH)D levels are associated with significant metabolic health improvements post-surgery, notably, that such baseline levels are able to predict those who attain T2DM remission. This highlights the importance of 25(OH)D as a predictive biomarker of post-surgery benefits.

Mechanisms of Central Hypogonadism.

Reproductive function depends upon an operational hypothalamo-pituitary-gonadal (HPG) axis. Due to its role in determining survival versus reproductive strategies, the HPG axis is vulnerable to a diverse plethora of signals that ultimately manifest with Central Hypogonadism (CH) in all its many guises. Acquired CH can result from any pituitary or hypothalamic lesion, including its treatment (such as surgical resection and/or radiotherapy). The HPG axis is particularly sensitive to the suppressive effects of hyperprolactinaemia that can occur for many reasons, including prolactinomas, and as a side effect of certain drug therapies. Physiologically, prolactin (combined with the suppressive effects of autonomic neural signals from suckling) plays a key role in suppressing the gonadal axis and establishing temporary CH during lactation. Leptin is a further key endocrine regulator of the HPG axis. During starvation, hypoleptinaemia (from diminished fat stores) results in activation of hypothalamic agouti-related peptide neurons that have a dual purpose to enhance appetite (important for survival) and concomitantly suppresses GnRH neurons via effects on neural kisspeptin release. Obesity is associated with hyperleptinaemia and leptin resistance that may also suppress the HPG axis. The suppressibility of the HPG axis also leaves it vulnerable to the effects of external signals that include morphine, anabolic-androgenic steroids, physical trauma and stress, all of which are relatively common causes of CH. Finally, the HPG axis is susceptible to congenital malformations, with reports of mutations within >50 genes that manifest with congenital CH, including Kallmann Syndrome associated with hyposmia or anosmia (reduction or loss of the sense of smell due to the closely associated migration of GnRH with olfactory neurons during embryogenesis). Analogous to the HPG axis itself, patients with CH are often vulnerable, and their clinical management requires both sensitivity and empathy.

Exogenous ketosis in patients with type 2 diabetes: Safety, tolerability and effect on glycaemic control.

INTRODUCTION: Ketogenic diets have shown to improve glycaemic control in patients with type 2 diabetes. This study investigated the safety, tolerability, and effects on glycaemic control in patients with type 2 diabetes of an exogenous ketone monoester (KE) capable of inducing fasting-like elevations in serum ß-hydroxybutyrate (ßHB) without the need for caloric or carbohydrate restriction. METHODS: Twenty one participants (14 men and 7 women, aged 45 ± 11 years) with insulin-independent type 2 diabetes, and unchanged hypoglycaemic medication for the previous 6 months, were recruited for this non-randomised interventional study. Participants wore intermittent scanning glucose monitors (IS-GM) for a total of 6 weeks and were given 25 ml of KE 3 times daily for 4 weeks. Serum electrolytes, acid-base status, and ßHB concentrations were measured weekly and cardiovascular risk markers were measured before and after the intervention. The primary endpoints were safety and tolerability, with the secondary endpoint being glycaemic control. RESULTS: The 21 participants consumed a total of 1,588 drinks (39.7 litres) of KE over the course of the intervention. Adverse reactions were mild and infrequent, including mild nausea, headache, and gastric discomfort following fewer than 0.5% of the drinks. Serum electrolyte concentrations, acid-base status, and renal function remained normal throughout the study. Compared to baseline, exogenous ketosis induced a significant decrease in all glycaemic control markers, including fructosamine (335 ± 60 µmol/L to 290 ± 49 µmol/L, p < .01), HbA1c (61 ± 10 mmol/mol to 55 ± 9 mmol/mol [7.7 ± 0.9% to 7.2 ± 0.9%], p < .01), mean daily glucose (7.8 ± 1.4 mM to 7.4 ± 1.3 mM [140 ± 23 mg/dl to 133 ± 25 mg/dl], p < .01) and time in range (67 ± 11% to 69 ± 10%, p < .01). CONCLUSIONS: Constant ketone monoester consumption over 1 month was safe, well tolerated, and improved glycaemic control in patients with type 2 diabetes.

Early Predictors of Gestational Diabetes Mellitus in IVF-Conceived Pregnancies.

OBJECTIVE: Gestational diabetes mellitus (GDM) is associated with adverse maternal and fetal outcomes. This study aimed to identify early and reliable GDM predictors that would enable implementation of preventive and management measures. METHODS: The participants were a 28-week prospective cohort of in vitro fertilization (IVF)-conceived pregnant women (≤39 years, body mass index [BMI] 18.5-38 kg/m2) without a known history of diabetes mellitus. Fasting blood samples were analyzed at baseline (pre-IVF) and 12 weeks' gestation for reproductive hormones, glucose, serum insulin, lipids, thyroid function, adiponectin, and lipopolysaccharide-binding protein. At 28 weeks, a 75-g oral glucose tolerance test was used to screen for GDM. RESULTS: For the overall group at baseline, 22% had BMI ≥30 kg/m2, 45% had polycystic ovary syndrome, 16% had hemoglobin A1C of 5.7% to 6.1%, and 14% had a past history of GDM. At 28 weeks of gestation (n = 158), 34 women had developed GDM and 124 had not. Significant baseline predictors of GDM onset included greater BMI (29.0 vs 25.8 kg/m2), older age (34 vs 32 years), higher levels of follicle-stimulating hormone/luteinizing hormone ratio (1.2 vs 1.0), hemoglobin A1C (5.5 vs 5.2%), insulin (10.6 vs 7.1 µIU/mL), homeostatic model assessment of insulin resistance (2.2 vs 1.7), total cholesterol (199 vs 171 mg/dL), and low-density lipoprotein cholesterol (123 vs 105 mg/dL), and lower triglyceride levels (74 vs 76 mg/dL). Significant 12-week GDM predictors included greater maternal weight gain (delta: 3.4 vs 1.5 kg) and higher levels of insulin (11.3 vs 7.6 µIU/mL), triglycerides (178 vs 120 mg/dL), and homeostatic model assessment of insulin resistance (2.3 vs 1.5). Twelve-week BMI is a predictor of GDM following adjustment for polycystic ovary syndrome status and maternal age. CONCLUSION: While preconception maternal BMI, age, and follicle-stimulating hormone/luteinizing hormone ratio are predictors of subsequent development of GDM, early IVF-conceived gestational weight gain is the best predictor of GDM onset.

Asprosin, a novel pleiotropic adipokine implicated in fasting and obesity-related cardio-metabolic disease: Comprehensive review of preclinical and clinical evidence.

White adipose tissue is a dynamic endocrine organ that releases an array of adipokines, which play a key role in regulating metabolic homeostasis and multiple other physiological processes. An altered adipokine secretion profile from adipose tissue depots frequently characterizes obesity and related cardio-metabolic diseases. Asprosin is a recently discovered adipokine that is released in response to fasting. Following secretion, asprosin acts - via an olfactory G-protein coupled receptor and potentially via other unknown receptor(s) - on hepatocytes and agouti-related peptide-expressing neurons in the central nervous system to stimulate glucose secretion and promote appetite, respectively. A growing body of both in vitro and in vivo studies have shown asprosin to exert a number of effects on different metabolic tissues. Indeed, asprosin can attenuate insulin signalling and promote insulin resistance in skeletal muscle by increasing inflammation and endoplasmic reticulum stress. Interestingly, asprosin may also play a protective role in cardiomyocytes that are exposed to hypoxic conditions. Moreover, clinical studies have reported elevated circulating asprosin levels in obesity, type 2 diabetes and other obesity-related cardio-metabolic diseases, with significant associations to clinically relevant parameters. Understanding the spectrum of the effects of this novel adipokine is essential in order to determine its physiologic role and its significance as a potential therapeutic target and/or a biomarker of cardio-metabolic disease. The present review offers a comprehensive overview of the published literature on asprosin, including both clinical and preclinical studies, focusing on its role in metabolism and cardio-metabolic disease.

Sodium in the dermis colocates to glycosaminoglycan scaffold, with diminishment in type 2 diabetes mellitus.

BACKGROUND: Dietary sodium intake mismatches urinary sodium excretion over prolonged periods. Our aims were to localize and quantify electrostatically bound sodium within human skin using triple-quantum-filtered (TQF) protocols for MRI and magnetic resonance spectroscopy (MRS) and to explore dermal sodium in type 2 diabetes mellitus (T2D). METHODS: We recruited adult participants with T2D (n = 9) and euglycemic participants with no history of diabetes mellitus (n = 8). All had undergone lower limb amputations or abdominal skin reduction surgery for clinical purposes. We used 20 µm in-plane resolution 1H MRI to visualize anatomical skin regions ex vivo from skin biopsies taken intraoperatively, 23Na TQF MRI/MRS to explore distribution and quantification of freely dissolved and bound sodium, and inductively coupled plasma mass spectrometry to quantify sodium in selected skin samples. RESULTS: Human dermis has a preponderance (>90%) of bound sodium that colocalizes with the glycosaminoglycan (GAG) scaffold. Bound and free sodium have similar anatomical locations. T2D associates with a severely reduced dermal bound sodium capacity. CONCLUSION: We provide the first evidence to our knowledge for high levels of bound sodium within human dermis, colocating to the GAG scaffold, consistent with a dermal "third space repository" for sodium. T2D associates with diminished dermal electrostatic binding capacity for sodium.

Relationship Between Maternal Bone Biomarkers and Fetal Adiposity Through Normal Pregnancy.

PURPOSE: To examine the association of maternal bone markers [sclerostin, soluble receptor activator of nuclear factor-κB ligand (sRANKL), osteocalcin, 25-hydroxyvitamin D3] with fetal intra-abdominal and subcutaneous adipose tissue deposition and birthweight during normal pregnancy. METHODS: One hundred pregnant women (aged 30.4 ±â€…5.6 years, mean ±â€…SD) with prepregnancy body mass index = 24.1 ±â€…4.6 kg/m2 were seen prospectively during each trimester. At each visit they were submitted to anthropometric measurements, a fasting blood sampling, a 75-g oral glucose tolerance test, and a fetal ultrasonogram. At birth, neonates had birth weight measurement. RESULTS: In the second trimester, maternal sclerostin concentrations correlated positively with fetal abdominal circumference and birth weight; maternal sRANKL concentrations correlated positively with fetal abdominal subcutaneous fat thickness, sagittal abdominal diameter, and abdominal circumference. Fetuses born to mothers with greater (>254 ng/mL), compared to fetuses born to mothers with lower (≤254ng/mL), sRANKL concentrations had greater abdominal circumference, sagittal diameter, and abdominal subcutaneous fat thickness. Maternal serum sclerostin concentrations were the best positive predictors of birth weight. In the third trimester maternal sclerostin concentrations correlated positively with fetal sagittal abdominal diameter; maternal sRANKL concentrations positively correlated with fetal abdominal circumference and fetal abdominal sagittal diameter. CONCLUSIONS: Maternal bone markers sclerostin and sRANKL may relate to fetal intra-abdominal adipose tissue deposition through as yet unknown direct or indirect mechanisms, thus contributing to birthweight.

Mechanisms of Insulin Resistance at the Crossroad of Obesity with Associated Metabolic Abnormalities and Cognitive Dysfunction.

Obesity mediates most of its direct medical sequelae through the development of insulin resistance (IR). The cellular effects of insulin occur through two main postreceptor pathways that are the phosphatidylinositol 3-kinase (PI3-K) and the mitogen-activated protein kinase (MAP-K) pathways. Obesity-related IR implicates the PI3-K pathway that confers the metabolic effects of insulin. Numerous and complex pathogenic pathways link obesity with the development of IR, including chronic inflammation, mitochondrial dysfunction (with the associated production of reactive oxygen species and endoplasmic reticulum stress), gut microbiota dysbiosis and adipose extracellular matrix remodelling. IR itself plays a key role in the development of metabolic dysfunction, including hypertension, dyslipidaemia and dysglycaemia. Furthermore, IR promotes weight gain related to secondary hyperinsulinaemia, with a resulting vicious cycle of worsening IR and its metabolic sequelae. Ultimately, IR underlies obesity-related conditions such as type 2 diabetes mellitus (T2D) and polycystic ovary syndrome (PCOS). IR also underlies many obesity-related malignancies, through the effects of compensatory hyperinsulinaemia on the relatively intact MAP-K insulin pathway, which controls cellular growth processes and mitoses. Furthermore, the emergent data over recent decades support an important role of obesity- and T2D-related central IR in the development of cognitive dysfunction, including effects on hippocampal synaptic plasticity. Importantly, IR is largely reversible through the optimisation of lifestyle factors that include regular engagement in physical activity with the avoidance of sedentariness, improved diet including increased fibre intake and sleep sufficiency. IR lies at the key crossroad between obesity and both metabolic and cognitive dysfunction. Given the importance of IR in the pathogenesis of many 21st century chronic diseases and its eminent reversibility, it is important that we all embrace and facilitate optimised lifestyles to improve the future health and wellbeing of the populace.

Obesity and polycystic ovary syndrome.

The increased global prevalence of obesity over the last 40-years has driven a rise in prevalence of obesity-related co-morbidities, including polycystic ovary syndrome (PCOS). On a background of genetic susceptibility, PCOS often becomes clinically manifest following weight gain, commonly during adolescence. A common endocrinopathy affecting between 6%-10% of reproductive-age women, PCOS presents with the cardinal features of hyperandrogenism, reproductive and metabolic dysfunction. PCOS associates with insulin resistance, independently of (but amplified by) obesity. Insulin resistance in PCOS is characterized by abnormal post-receptor signalling within the phosphatidylinositol-kinase (PI3-K) pathway. Multiple factors (including most notably, weight gain) contribute towards the severity of insulin resistance in PCOS. Compensatory hyperinsulinaemia ensues, resulting in over-stimulation of the (intact) post-receptor mitogen-activated protein kinase (MAP-K) insulin pathway, with consequent implications for steroidogenesis and ovarian function. In this concise review, we explore the effects of weight gain and obesity on the pathogenesis of PCOS from the perspective of its three cardinal features of hyperandrogenism, reproductive and metabolic dysfunction, with a focus on the central mediating role of the insulin pathway. We also consider key lifestyle strategies for the effective management of obese and overweight women with PCOS.

Impact of the COVID-19 pandemic on neuroendocrine tumour services in England.

PURPOSE: During the COVID-19 pandemic, there have been particular concerns regarding the related impact on specialist tumour services. Neuroendocrine tumour (NET) services are delivered in a highly specialised setting, typically delivered in a small number of centres that fulfil specific criteria as defined by the European Neuroendocrine Tumour Society (ENETS). We aimed to address the COVID-19-related impact on specialist NET tumour services in England and other countries. METHODS: Electronic survey addressing patient access and delivery of care distributed to all ENETS Centres of Excellence (CoE) in England and matching number of ENETS CoE elsewhere. Semi-quantitative and qualitative analyses of survey responses were performed. RESULTS: Survey response of ENETS CoE in England was 55% (6/11). Responses from six non-UK ENETS CoE elsewhere were received and analysed in a similar manner. Relevant disruption of various NET services was noted across all responding Centres, which included delayed patient appointments and investigations, reduced availability of treatment modalities including delayed surgical treatment and a major negative impact on research activities. The comparison between English and non-UK ENETS CoE suggested that the former had significantly greater concerns related to future research funding (p = 0.014), whilst having less disruption to multidisciplinary meetings (p = 0.01). A trend was also noted towards virtual patient appointments in ENETS CoE in England vs. elsewhere (p = 0.092). CONCLUSIONS: Restoration of highly specialised NET services following COVID-19 and planning for future service delivery and research funding must take account of the severe challenges encountered during the pandemic.

The Health Benefits of Dietary Fibre.

BACKGROUND: Dietary fibre consists of non-digestible forms of carbohydrate, usually as polysaccharides that originate from plant-based foods. Over recent decades, our diet within Westernised societies has changed radically from that of our hominid ancestors, with implications for our co-evolved gut microbiota. This includes increased ingestion of ultra-processed foods that are typically impoverished of dietary fibre, and associated reduction in the intake of fibre-replete plant-based foods. Over recent decades, there has been a transformation in our understanding of the health benefits of dietary fibre. OBJECTIVE: To explore the current medical literature on the health benefits of dietary fibre, with a focus on overall metabolic health. DATA SOURCES: We performed a narrative review, based on relevant articles written in English from a PubMed search, using the terms 'dietary fibre and metabolic health'. RESULTS: In the Western world, our diets are impoverished of fibre. Dietary fibre intake associates with overall metabolic health (through key pathways that include insulin sensitivity) and a variety of other pathologies that include cardiovascular disease, colonic health, gut motility and risk for colorectal carcinoma. Dietary fibre intake also correlates with mortality. The gut microflora functions as an important mediator of the beneficial effects of dietary fibre, including the regulation of appetite, metabolic processes and chronic inflammatory pathways. CONCLUSIONS: Multiple factors contribute to our fibre-impoverished modern diet. Given the plethora of scientific evidence that corroborate the multiple and varied health benefits of dietary fibre, and the risks associated with a diet that lacks fibre, the optimization of fibre within our diets represents an important public health strategy to improve both metabolic and overall health. If implemented successfully, this strategy would likely result in substantial future health benefits for the population.

Modification of fecal microbiota as a mediator of effective weight loss and metabolic benefits following bariatric surgery.

INTRODUCTION: Bariatric surgery (primarily Laparoscopic Sleeve Gastrectomy [LSG] and Roux-en-Y Gastric Bypass [RYGB]) is an efficacious and durable therapeutic option for weight loss in obesity. The mechanisms that mediate weight loss following bariatric surgery remain incompletely understood. AREAS COVERED: Pubmed search of published data on fecal microbiota, metabolic health, LSG, and RYGB. The fecal microbiome plays a key role in the establishment and maintenance of metabolic wellbeing, and may also contribute (through fecal dysbiosis) to metabolic dysfunction. LSG and RYGB both result in characteristic, procedure-specific changes to the fecal microbiota that may mediate at least some of the resultant weight-loss and metabolically beneficial effects, when applied to the management of obesity. EXPERT OPINION: The human fecal microbiome, containing around 100 trillion microbes, evolved over millions of years and interacts symbiotically with its human host. Rodent-based studies have provided insights into the complexities of the gut-microbiome-brain axis. This includes the important role of the gut microbiome in the mediation of normal immunological development, inflammatory pathways, metabolic functioning, hypothalamic appetite regulation, and the absorption of essential nutrients as by-products of bacterial metabolism. Fecal transformation is likely to provide an important therapeutic target for future prevention and management of obesity and metabolic dysfunction.

Psoriatic disease and body composition: A systematic review and narrative synthesis.

BACKGROUND: Obesity is a leading comorbidity in psoriatic disease, including both psoriasis (PsO) and psoriatic arthritis (PsA), and is associated with adverse metabolic and cardiovascular (CV) outcomes. Anthropometric parameters, such as weight, body mass index (BMI) and waist-to-hip ratio, have been extensively reported in psoriatic disease. However, the associations of body composition and fat distribution with psoriasis have not yet been fully defined. OBJECTIVES: To identify whether patients with psoriatic disease, including psoriatic arthritis, have altered body composition compared with the general population, and to review existing modalities for the assessment of body composition. METHODS: Electronic searches of the literature were conducted in PubMed, Medline (Ovid®), Embase (Ovid®), Cochrane Central Register of Controlled Trials (CENTRAL) and Google Scholar. Titles and abstracts were reviewed by two authors independently against a set of prespecified inclusion/exclusion criteria. The research question was answered with a systematic literature review and results were summarized narratively. RESULTS: Twenty-five full text articles met the inclusion criteria and were included in the final narrative analysis. The studies were of heterogeneous design and used a range of objective measures to assess body composition, including simple anthropometric measures, bioimpedance analysis (BIA), dual energy X-ray absorptiometry (DXA) and computed tomography (CT). Few studies met all the quality assessment criteria. Clinical heterogeneity prevented meta-analysis. CONCLUSIONS: Patients with psoriatic disease reveal defined body composition changes that are independent of obesity and the customary metabolic syndrome, including higher overall body fat, visceral fat and sarcopenia. These findings emphasize that patients with psoriatic disease should be screened for abnormal adipose effects beyond their weight and body mass index (BMI). Our findings show that the last decade has seen an exciting expansion of research interest in the development and validation of new modalities for the assessment of body composition. There is no consensus on the optimal assessment method of body composition for this diverse group; hence there is a need for validation of existing modalities and standardization of assessment tools.