The Role of Mitochondria-Linked Fatty-Acid Uptake-Driven Adipogenesis in Graves Orbitopathy.

CONTEXT: Depot-specific expansion of orbital adipose tissue (OAT) in Graves orbitopathy (GO; an autoimmune condition producing proptosis, visual impairment and reduced quality of life) is associated with fatty acid (FA)-uptake-driven adipogenesis in preadipocytes/fibroblasts (PFs). OBJECTIVE: This work sought a role for mitochondria in OAT adipogenesis in GO. METHODS: Confluent PFs from healthy OAT (OAT-H), OAT from GO (OAT-GO) and white adipose tissue in culture medium compared with culture medium containing a mixed hormonal cocktail as adipogenic medium (ADM), or culture-medium containing FA-supplementation, oleate:palmitate:linoleate (45:30:25%) with/without different concentration of mitochondrial biosubstrate adenosine 5'-diphosphate/guanosine 5'-diphosphate (ADP/GDP), AICAR (adenosine analogue), or inhibitor oligomycin-A for 17 days. Main outcome measures included oil-red-O staining and foci count of differentiated adipocytes for in vitro adipogenesis, flow cytometry, relative quantitative polymerase chain reaction, MTS-assay/106 cells, total cellular-ATP detection kit, and Seahorse-XFe96-Analyzer for mitochondria and oxidative-phosphorylation (OXPHOS)/glycolysis-ATP production analysis. RESULTS: During early adipogenesis before adipocyte formation (days 0, 4, and7), we observed OAT-specific cellular ATP production via mitochondrial OXPHOS in PFs both from OAT-H and OAT-GO, and substantially disrupted OXPHOS-ATP/glycolysis-ATP production in PFs from OAT-GO, for example, a 40% reduction in OXPHOS-ATP and trend-increased glycolysis-ATP production on days 4 and 7 compared with day 0, which contrasted with the stable levels in OAT-H. FA supplementation in culture-medium triggered adipogenesis in PFs both from OAT-H and OAT-GO, which was substantially enhanced by 1-mM GDP reaching 7% to 18% of ADM adipogenesis. The FA-uptake-driven adipogenesis was diminished by oligomycin-A but unaffected by treatment with ADP or AICAR. Furthermore, we observed a significant positive correlation between FA-uptake-driven adipogenesis by GDP and the ratios of OXPHOS-ATP/glycolysis-ATP through adipogenesis of PFs from OAT-GO. CONCLUSION: Our study confirmed that FA uptake can drive OAT adipogenesis and revealed a fundamental role for mitochondria-OXPHOS in GO development, which provides potential for therapeutic interventions.

CATS II Long-term Anthropometric and Metabolic Effects of Maternal Sub-optimal Thyroid Function in Offspring and Mothers.

CONTEXT AND OBJECTIVES: The Controlled Antenatal Thyroid Screening Study I (CATS-I) was a randomized controlled trial investigating the effects of levothyroxine therapy for suboptimal gestational thyroid function (SGTF), comparing outcomes in children of treated (SGTF-T) with untreated (SGTF-U) women during pregnancy. This follow-up study, CATS-II, reports the long-term effects on anthropometric, bone, and cardiometabolic outcomes in mothers and offspring and includes a group with normal gestational thyroid function (NGTF). DESIGN & PARTICIPANTS: 332 mothers (197 NGTF, 56 SGTF-U, 79 SGTF-T) aged 41.2±5.3 years (mean±SD) and 326 paired children assessed 9.3±1.0 years after birth for (i) body mass index (BMI); (ii) lean, fat, and bone mass by dual-energy X-ray absorptiometry; (iii) blood pressure, augmentation index, and aortic pulse-wave-velocity; and (iv) thyroid function, lipids, insulin, and adiponectin. The difference between group means was compared using linear regression. RESULTS: Offspring's measurements were similar between groups. Although maternal BMI was similar between groups at CATS-I, after 9 years (at CATS-II) SGTF-U mothers showed higher BMI (median [interquartile ratio] 28.3 [24.6-32.6] kg/m2) compared with NGTF (25.8 [22.9-30.0] kg/m2; P = 0.029), driven by fat mass increase. At CATS-II SGTF-U mothers also had higher thyroid-stimulating hormone (TSH) values (2.45 [1.43-3.50] mU/L) than NGTF (1.54 [1.12-2.07] mU/L; P = 0.015), since 64% had never received levothyroxine. At CATS-II, SGTF-T mothers had BMI (25.8 [23.1-29.8] kg/m2, P = 0.672) and TSH (1.68 [0.89-2.96] mU/L; P = 0.474) values similar to NGTF mothers. CONCLUSIONS: Levothyroxine supplementation of women with SGTF did not affect long-term offspring anthropometric, bone, and cardiometabolic measurements. However, absence of treatment was associated with sustained long-term increase in BMI and fat mass in women with SGTF.

Controlled Antenatal Thyroid Screening II: Effect of Treating Maternal Suboptimal Thyroid Function on Child Behavior.

CONTEXT & OBJECTIVES: The Controlled Antenatal Thyroid Screening (CATS) study was the first randomized controlled trial to investigate effects of treating suboptimal gestational thyroid function (SGTF) on child cognition. Since observational studies indicated that SGTF may also increase symptoms of autism and attention-deficit/hyperactivity disorder (ADHD), the CATS cohort was used to investigate whether treatment of mothers affected their children's behavior. DESIGN & PARTICIPANTS: Mothers (N = 475) completed 3 questionnaires: the Strengths and Difficulties Questionnaire (SDQ), the Child ADHD Questionnaire, and the Social Communication Questionnaire (SCQ, used as a screen for autism spectrum disorder [ASD]), about their children (mean age 9.5 years). Group comparisons of total scores, numbers of children above clinical thresholds, and association between high maternal free thyroxine (FT4) (> 97.5th percentile of the UK cohort, "overtreated") and child neurodevelopment were reported. RESULTS: There were no differences in total scores between normal gestational thyroid function (GTF) (n = 246), treated (n = 125), and untreated (n = 104) SGTF groups. More children of treated mothers scored above clinical thresholds, particularly the overtreated. Scores were above thresholds in SDQ conduct (22% vs 7%), SCQ total scores (7% vs 1%), and ADHD hyperactivity (17% vs 5%) when comparing overtreated (n = 40) and untreated (N = 100), respectively. We identified significantly higher mean scores for SDQ conduct (adjusted mean difference [AMD] 0.74; 95% confidence interval [CI], 0.021-1.431; P = 0.040, effect size 0.018) and ADHD hyperactivity (AMD 1.60, 95% CI, 0.361-2.633; P = 0.003, effect size 0.028) comparing overtreated with normal-GTF children. CONCLUSIONS: There was no overall association between SGTF and offspring ADHD, ASD, or behavior questionnaire scores. However, children of "overtreated" mothers displayed significantly more ADHD symptoms and behavioral difficulties than those of normal-GTF mothers. Thyroxine supplementation during pregnancy requires monitoring to avoid overtreatment.

Dietary Nitrate Supplementation Reduces Circulating Platelet-Derived Extracellular Vesicles in Coronary Artery Disease Patients on Clopidogrel Therapy: A Randomised, Double-Blind, Placebo-Controlled Study.

Extracellular vesicles (EVs) are implicated in the pathogenesis of cardiovascular disease (CVD). Specifically, platelet-derived EVs are highly pro-coagulant, promoting thrombin generation and fibrin clot formation. Nitrate supplementation exerts beneficial effects in CVD, via an increase in nitric oxide (NO) bioavailability. Clopidogrel is capable of producing NO-donating compounds, such as S-nitrosothiols (RSNO) in the presence of nitrite and low pH. The aim of this study was to assess the effect of nitrate supplementation with versus without clopidogrel therapy on circulating EVs in coronary artery disease (CAD) patients. In this randomized, double-blind, placebo-controlled study, CAD patients with (n = 10) or without (n = 10) clopidogrel therapy received a dietary nitrate supplement (SiS nitrate gel) or identical placebo. NO metabolites and platelet activation were measured using ozone-based chemiluminescence and multiple electrode aggregometry. EV concentration and origin were determined using nanoparticle tracking analysis and time-resolved fluorescence. Following nitrate supplementation, plasma RSNO was elevated (4.7 ± 0.8 vs 0.2 ± 0.5 nM) and thrombin-receptor mediated platelet aggregation was reduced (-19.9 ± 6.0 vs 4.0 ± 6.4 U) only in the clopidogrel group compared with placebo. Circulating EVs were significantly reduced in this group (-1.183e11 ± 3.15e10 vs -9.93e9 ± 1.84e10 EVs/mL), specifically the proportion of CD41+ EVs (-2,120 ± 728 vs 235 ± 436 RFU [relative fluorescence unit]) compared with placebo. In vitro experiments demonstrated clopidogrel-SNO can reduce platelet-EV directly (6.209e10 ± 4.074e9 vs 3.94e11 ± 1.91e10 EVs/mL). In conclusion, nitrate supplementation reduces platelet-derived EVs in CAD patients on clopidogrel therapy, increasing patient responsiveness to clopidogrel. Nitrate supplementation may represent a novel approach to moderating the risk of thrombus formation in CAD patients.

How to help the aging male? Current approaches to hypogonadism in primary care.

Hypogonadism is a common condition which occurs more frequently in older men. It is characterized by low testosterone (T) and is associated with symptoms which are often nonspecific. A key symptom is low libido, but it can also be associated with erectile dysfunction, reduced muscle mass and strength, increased body fat, reduced bone mineral density and osteoporosis, reduced vitality, and depressed mood. Hypogonadism is linked with a variety of comorbid conditions including erectile dysfunction, metabolic syndrome, diabetes, obesity, and osteoporosis. However, the condition is often underdiagnosed. T supplementation in hypogonadism is associated with a range of benefits including improved sexual function, increased lean body mass and/or reduced fat mass, and improved bone mineral density. A variety of T supplementation formulations are available. Although there is no evidence of increased risk of initiating prostate cancer with T supplementation, it is contraindicated in men with prostate cancer. It is important that primary care physicians are aware of both the signs and symptoms of hypogonadism, the monitoring and testing that is required and the merits and advantages of the various T preparations to ensure optimal management of the condition with a treatment approach that best suits patients' needs.

The sympathetic nervous system in polycystic ovary syndrome: a novel therapeutic target?

Polycystic ovary syndrome (PCOS) is a common endocrine condition associated with long-term health risks, including type 2 diabetes and vascular dysfunction in addition to reproductive sequelae. Many of the common features of PCOS, such as central obesity, hyperinsulinaemia and obstructive sleep apnoea (OSA), are associated with chronic sympathetic overactivity, suggesting that sympathoexcitation may be involved in the pathogenesis of this condition. Rodent models of polycystic ovaries have shown that ovarian sympathetic outflow may be increased, accompanied by elevated intra-ovarian synthesis of nerve growth factor (NGF) which may be involved in initiation of ovarian pathology. Patients with PCOS have evidence of increased muscle sympathetic nerve activity (MSNA), altered heart rate variability and attenuated heart rate recovery postexercise, compared with age- and BMI-matched controls, suggesting a generalized increase in sympathetic nerve activity. Active weight loss can reduce MSNA and whole body noradrenaline spillover, whereas low-frequency electroacupuncture decreased MSNA in overweight women with PCOS. Treatment of OSA with continuous positive airways pressure may reduce plasma noradrenaline levels and diastolic blood pressure and improve cardiac sympathovagal balance. Renal sympathetic denervation also reduced MSNA, noradrenaline spillover and blood pressure in two PCOS subjects with hypertension, accompanied by improved insulin sensitivity. The sympathetic nervous system may thus offer a new therapeutic target in PCOS but larger and longer-term studies are needed before these treatments can be considered in clinical practice.

Effects of dehydroepiandrosterone replacement on vascular function in primary and secondary adrenal insufficiency: a randomized crossover trial.

CONTEXT: Patients with Addison's disease and hypopituitarism have increased mortality, chiefly related to vascular disease. Both diseases are characterized by dehydroepiandrosterone (DHEA) deficiency, yet this is not usually corrected. It is unclear whether treatment of these conditions with DHEA improves cardiovascular risk. OBJECTIVE: The aim of the study was to evaluate the effects of DHEA on arterial stiffness and endothelial function in subjects with Addison's disease and hypopituitarism. DESIGN AND INTERVENTION: Forty subjects (20 with Addison's disease, 20 with panhypopituitarism) were assigned to consecutive 12-wk treatment periods of DHEA 50 mg or placebo in a randomized, double-blind, crossover design separated by an 8-wk washout. MAIN OUTCOME MEASURES: Primary outcome parameters were measures of arterial stiffness [augmentation index, central blood pressure, brachial and aortic pulse wave velocity (PWV)] and endothelial function. Serum androgens, anthropometry, and metabolic biochemistry (lipids, homeostasis model of assessment for insulin resistance, high sensitivity C-reactive protein, adiponectin, plasminogen activator inhibitor-1) were also assessed. RESULTS: Despite normalization of DHEA sulfate, androstenedione, and testosterone (females), DHEA replacement did not affect augmentation index, aortic PWV, brachial PWV, central blood pressure, or endothelial function. DHEA did not affect any anthropometric or metabolic measures, apart from a small reduction in high-density lipoprotein cholesterol (-0.08 mmol/liter; P = 0.007; 95% confidence interval for the difference, -0.13 to -0.02 mmol/liter). CONCLUSIONS: Short-term DHEA supplementation does not significantly affect measures of arterial stiffness or endothelial function in patients with adrenal insufficiency.