Gut: A key player in the pathogenesis of type 2 diabetes?

The gut regulates glucose and energy homeostasis; thus, the presence of ingested nutrients into the gut activates sensing mechanisms that affect both glucose homeostasis and regulate food intake. Increasing evidence suggest that gut may also play a key role in the pathogenesis of type 2 diabetes which may be related to both the intestinal microbiological profile and patterns of gut hormones secretion. Intestinal microbiota includes trillions of microorganisms but its composition and function may be adversely affected in type 2 diabetes. The intestinal microbiota may be responsible of the secretion of molecules that may impair insulin secretion/action. At the same time, intestinal milieu regulates the secretion of hormones such as GLP-1, GIP, ghrelin, gastrin, somatostatin, CCK, serotonin, peptide YY, GLP-2, all of which importantly influence metabolism in general and in particular glucose metabolism. Thus, the aim of this paper is to review the current evidence on the role of the gut in the pathogenesis of type 2 diabetes, taking into account both hormonal and microbiological aspects.

Adrenal disorders: Is there Any role for vitamin D?

An emerging branch of research is examining the linkage between Vitamin D and nonskeletal disorders, including endocrine diseases. In this regard, a still little studied aspect concerns the involvement of vitamin D in adrenal gland disorders. Adrenal gland disorders, which might be theoretically affected by vitamin D unbalance, include adrenal insufficiency, Cushing's syndrome, adrenocortical tumors and hyperaldosteronism. In this review, we provide an updated document, which tries to collect and discuss the limited evidence to be found in the literature about the relationship between vitamin D and adrenal disorders. We conclude that there is insufficient evidence proving a causal relationship between vitamin D levels and adrenal disorders. Evidence coming from cross-sectional clinical studies can hardly clarify what comes first between vitamin D unbalance and adrenal disease. On the other hand, longitudinal studies monitoring the levels of vitamin D in patients with adrenal disorders or, conversely, the possible development of adrenal pathologies in subjects affected by impaired vitamin D levels would be able to elucidate this still unclear issue.

Current evidence on vitamin D deficiency and kidney transplant: What's new?

Kidney transplant is the treatment of choice for end-stage chronic kidney disease. Kidneys generate 1,25-dihydroxyvitamin D (calcitriol) from 25-hydroxyvitamin D (calcidiol) for circulation in the blood to regulate calcium levels. Transplant patients with low calcidiol levels have an increased risk of metabolic and endocrine problems, cardiovascular disease, type 2 diabetes mellitus, poor graft survival, bone disorders, cancer, and mortality rate. The recommended calcidiol level after transplant is at least 30 ng/mL (75 nmol/L), which could require 1000-3000 IU/d vitamin D3 to achieve. Vitamin D3 supplementation studies have found improved endothelial function and acute rejection episodes. However, since kidney function may still be impaired, raising calcidiol levels may not lead to normal calcitriol levels. Thus, supplementation with calcitriol or an analog, alfacalcidiol, is often employed. Some beneficial effects found include possible improved bone health and reduced risk of chronic allograft nephropathy and cancer.

Does vitamin D play a role in autoimmune endocrine disorders? A proof of concept.

In the last few years, more attention has been given to the "non-calcemic" effect of vitamin D. Several observational studies and meta-analyses demonstrated an association between circulating levels of vitamin D and outcome of many common diseases, including endocrine diseases, chronic diseases, cancer progression, and autoimmune diseases. In particular, cells of the immune system (B cells, T cells, and antigen presenting cells), due to the expression of 1α-hydroxylase (CYP27B1), are able to synthesize the active metabolite of vitamin D, which shows immunomodulatory properties. Moreover, the expression of the vitamin D receptor (VDR) in these cells suggests a local action of vitamin D in the immune response. These findings are supported by the correlation between the polymorphisms of the VDR or the CYP27B1 gene and the pathogenesis of several autoimmune diseases. Currently, the optimal plasma 25-hydroxyvitamin D concentration that is necessary to prevent or treat autoimmune diseases is still under debate. However, experimental studies in humans have suggested beneficial effects of vitamin D supplementation in reducing the severity of disease activity. In this review, we summarize the evidence regarding the role of vitamin D in the pathogenesis of autoimmune endocrine diseases, including type 1 diabetes mellitus, Addison's disease, Hashimoto's thyroiditis, Graves' disease and autoimmune polyendocrine syndromes. Furthermore, we discuss the supplementation with vitamin D to prevent or treat autoimmune diseases.

Vitamin D and chronic diseases: the current state of the art.

The objective was to provide the current state of the art regarding the role of vitamin D in chronic diseases (osteoporosis, cancer, cardiovascular diseases, dementia, autism, type 1 and type 2 diabetes mellitus, male and female fertility). The document was drawn up by panelists that provided their contribution according to their own scientific expertise. Each scientific expert supplied a first draft manuscript on a specific aspect of the document's topic that was subjected to voting by all experts as "yes" (agreement with the content and/or wording) or "no" (disagreement). The adopted rule was that statements supported by ≥75 % of votes would be immediately accepted, while those with <25 % would be rejected outright. Others would be subjected to further discussion and subsequent voting, where ≥67 % support or, in an eventual third round, a majority of ≥50 % would be needed. This document finds that the current evidence support a role for vitamin D in bone health but not in other health conditions. However, subjects with vitamin D deficiency have been found to be at high risk of developing chronic diseases. Therefore, although at the present time there is not sufficient evidence to recommend vitamin D supplementation as treatment of chronic diseases, the treatment of vitamin D deficiency should be desiderable in order to reduce the risk of developing chronic diseases.

Adrenocortical tumors and insulin resistance: What is the first step?

The pathogenetic mechanisms underlying the onset of adrenocortical tumors (ACTs) are still largely unknown. Recently, more attention has been paid to the role of insulin and insulin-like growth factor (IGF) system on general tumor development and progression. Increased levels of insulin, IGF-1 and IGF-2 are associated with tumor cell growth and increased risk of cancer promotion and progression in patients with type 2 diabetes. Insulin resistance and compensatory hyperinsulinemia may play a role in adrenal tumor growth through the activation of insulin and IGF-1 receptors. Interestingly, apparently non-functioning ACTs are often associated with a high prevalence of insulin resistance and metabolic syndrome. However, it is unclear if ACT develops from a primary insulin resistance and compensatory hyperinsulinemia or if insulin resistance is only secondary to the slight cortisol hypersecretion by ACT. The aim of this review is to summarize the current evidence regarding the relationship between hyperinsulinemia and adrenocortical tumors.

DYSREGULATION OF THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS INCREASES CENTRAL BODY FAT ACCUMULATION IN MALES AFFECTED BY DIABETES MELLITUS AND LATE-ONSET HYPOGONADISM.

OBJECTIVE: Functional hypercortisolism (FH) is a condition which occurs in some clinical states, such as major depression, eating disorders, numerous psychiatric conditions, and diabetes mellitus (DM) and which exerts several negative systemic effects. No data exist on the potentially harmful role of FH on body composition. In this retrospective study, we evaluated the influence of hypothalamic-pituitary-adrenal (HPA) axis dysregulation on body composition in men affected by DM-associated late-onset hypogonadism (LOH). METHODS: Fourteen subjects affected by FH (FH-LOH) and 18 subjects not affected (N-LOH) were studied. Clinical, hormonal, and body composition measures were considered. RESULTS: The 2 groups had comparable age and weight. FH-LOH patients had lower levels of total (2 ± 0.27 ng/mL versus 2.31 ± 0.26 ng/mL; P = .003) and free (39.5 ± 6.44 pg/mL versus 46.8 ± 7.23 pg/mL; P = .005) (median, 38.7 [interquartile range, 36.1 to 41.3] pg/mL versus median, 46.1 [interquartile range, 40.4 to 52.7] pg/mL) testosterone compared to N-LOH patients. Abdominal fat amount was greater in FH-LOH than in N-LOH patients, even after adjustment for total testosterone. None of the bivariate correlations between body composition measures and hormonal variables were significant in N-LOH. Conversely, in FH-LOH, cortisol area under the curve (AUC) was found to be positively and significantly correlated with trunk (r = 0.933; P<.001) and abdominal fat (r = 0.852; P<.001) and negatively with lean leg (r = -0.607; P = .021). All of these associations were further confirmed upon linear regression analysis in FH-LOH (respectively, unstandardized ß = 10.988 [P<.001]; ß = 1.156 [P<.001]; ß = -7.675 [P = .021]). Multivariate regression analysis confirmed AUC cortisol as a predictor of trunk and abdominal fat in FH-LOH. CONCLUSION: Dysregulation of the HPA axis in LOH-associated DM seems to be involved in abdominal fat accumulation.

The role of psychological well-being in obese and overweight older adults.

Being obese or overweight is often associated with impaired quality of life and psychological well-being (PWB) in comparison with normal-weight people (Giuli et al., 2014), both in developed and developing countries. PWB is considered a very important correlate of subjective well-being in people with excess weight. The concept of PWB is based on Ryff's multidimensional model (Ryff, 2014), which considers well-being as eudaemonic concept, and includes six dimensions: autonomy, environmental mastery, personal growth, positive relations with others, purpose in life, and self-acceptance. Few studies have analyzed the role of specific correlates of perceived well-being in the obese and overweight Italian older population. The purpose of this study was to evaluate the role of perceived well-being in obese and overweight older adults. Our study included 124 overweight and obese older participants, aged 60 years or more, selected from patients attending the Division of Endocrinology, Department of Clinical and Molecular Sciences of Polytechnic University of Marche (Italy). As previously described (Giuli et al., 2014), the participants were recruited on the basis of specific inclusion/exclusion criteria, in a period of three years (January 2010-December 2012).

Influence of androgen receptor CAG polymorphism on sexual function recovery after testosterone therapy in late-onset hypogonadism.

INTRODUCTION: Androgen receptor (AR) CAG polymorphism has been found to influence sexual function. However, no study has evaluated its potential to condition sexual function recovery after testosterone replacement therapy (TRT) in a large cohort of hypogonadic subjects. AIM: To evaluate the role of this polymorphism in sexual function improvement after TRT in late-onset hypogonadism (LOH). METHODS: Seventy-three men affected by LOH were retrospectively considered. Evaluations were performed before TRT started (time 0) and before the sixth undecanoate testosterone injection. MAIN OUTCOME MEASURES: International Index of Erectile Function (IIEF) questionnaire (erectile function [EF], orgasmic function [OF], sexual desire [SD], intercourse satisfaction [IS], overall satisfaction [OS], and total IIEF-15 score); total and free testosterone and estradiol; AR gene CAG repeat number. RESULTS: TRT induced a significant increase in total and free testosterone and estradiol. All IIEF domains significantly improved after TRT. AR CAG repeats negatively and significantly correlated with all the variations (Δ-) of sexual function domains, except for Δ-OS. Conversely, Δ-total testosterone was found to be positively and significantly correlated with sexual function domain variations, except for Δ-IS and Δ-OS. Δ-estradiol did not correlate significantly with any of the variations of sexual function domains. After inclusion in generalized linear models, the number of AR gene CAG triplets was found to be independently and negatively associated with Δ-EF, Δ-SD, Δ-IS, and Δ-Total IIEF-15 score, whereas Δ-total testosterone was independently and positively associated with Δ-EF, Δ-OF, Δ-SD, and Δ-Total IIEF-15 score. However, after including time 0 total testosterone in the model, AR gene CAG triplets remained independently and negatively associated only with Δ-EF and Δ-Total IIEF-15 score, whereas Δ-total testosterone was independently and positively associated only with Δ-EF. CONCLUSIONS: Longer length of AR gene CAG repeat tract seems to lower TRT-induced improvement of sexual function in LOH.

Effects of in vitro supplementation with Syzygium cumini (L.) on platelets from subjects affected by diabetes mellitus.

The aim of this study was to assess the in vitro effects of Syzygium cumini (L.) (Sc) incubation on platelets from patients with diabetes, in order to test its efficacy as a potential adjuvant therapy. This study was performed on 77 patients with diabetes [29 in good (DMgc) and 48 in poor glycemic control (DMpc)] and 85 controls. In patients, platelets were analyzed at recruitment and after in vitro Sc incubation (final concentration of 200 µg/ml for 3 hours at 37 °C), whereas in controls only basal evaluation was performed. Lipoperoxide and nitric oxide (NO) levels, superoxide dismutase (SOD) and Na(+)/K(+) ATPase activities, total antioxidant capacity (TAC), and membrane fluidity tested by anisotropy of fluorescent probes 1-(4-trimethylaminophenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH) and 1-6-phenyl-1,3,5-hexatriene (DPH) were determined. Collagen-induced platelet aggregation was also evaluated. In vitro Sc activity counteracts oxidative damage, by improving platelet function through augmented membrane fluidity and Na(+)/K(+) ATPase activity; it also enhances antioxidant system functionality by increasing NO levels, SOD activity, and TAC and by decreasing lipoperoxide levels both in whole samples and in DMgc and DMpc. In addition, a slight tendency towards collagen-induced platelet aggregation decrease after Sc was observed. However, all these parameters, even after improvement, did not reach the levels of control subjects. Our results suggest that Sc may have a preventive and protective effect in oxidative damage progression associated with diabetes mellitus and its complications. If our data will be confirmed, Sc supplementation might become a further tool in the management of this disease, especially in view of its easy availability, safety, low cost, and absence of side effects.

Impact of adult growth hormone deficiency on metabolic profile and cardiovascular risk [Review].

Adult growth hormone deficiency (GHD) is a well defined clinical condition, which is characterized by abnormal body composition, impaired physical activity and decreased quality of life. In addition, in recent years, growing interest has been shown towards cardiovascular risks in adult patients affected by GHD. In this regard, GHD is widely known to be associated with increased mortality, likely due to the increase of risk factors, such as central obesity, impaired lipid and glucose profiles and other less-known risk factors, such as inflammatory cytokines, endothelial dysfunction and oxidative stress. However, very few papers have recently discussed this topic. In this review, the aim is to clarify this issue by discussing evidence regarding the effects of adult GHD on metabolic and cardiovascular profiles.

Androgen receptor gene CAG repeat polymorphism independently influences recovery of male sexual function after testosterone replacement therapy in postsurgical hypogonadotropic hypogonadism.

INTRODUCTION: Few and contradictory studies have evaluated the possible influence of androgen receptor (AR) gene CAG repeat polymorphism on male sexual function. AIM: In this study we evaluated the role of AR gene CAG repeat polymorphism in the recovery of sexual function after testosterone replacement therapy (TRT) in men affected by postsurgical hypogonadotropic hypogonadism, a condition which is often associated with hypopituitarism and in which the sexual benefits of TRT must be distinguished from those of pituitary-function replacement therapies. METHODS: Fifteen men affected by postsurgical hypogonadotropic hypogonadism were retrospectively assessed before and after TRT. MAIN OUTCOME MEASURES: Main outcome measures included sexual parameters as assessed by the International Index of Erectile Function questionnaire, levels of pituitary dependent hormones (total testosterone, free T3, free T4, cortisol, insulin-like growth factor-1 [IGF-1], prolactin), and results of genetic analysis (AR gene CAG repeat number). RESULTS: Plasma concentrations of free T3, free T4, cortisol, and prolactin did not vary significantly between the two phases, while testosterone and IGF-1 increased significantly after TRT. A significant improvement in all sexual parameters studied was found. The number of CAG triplets was negatively and significantly correlated with changes in all the sexual parameters, while opposite correlations were found between changes in sexual parameters and changes in testosterone levels; no correlation of change in IGF1 with change in sexual parameters was reported. On multiple linear regression analysis, after correction for changes in testosterone, nearly all the associations between the number of CAG triplets and changes in sexual parameters were confirmed. CONCLUSIONS: Shorter length AR gene CAG repeat number is associated with the recovery of sexual function after TRT in postsurgical male hypogonadotropic hypogonadism, independently of the effects of concomitant pituitary-replacement therapies.

Correlates of perceived health related quality of life in obese, overweight and normal weight older adults: an observational study.

BACKGROUND: Obesity is a complex multifactorial disease, which also has an impact on quality of life. The aim of this paper is to identify the correlates of perceived health related quality of life in obese, overweight and normal weight Italians older adults. METHODS: 205 subjects at the age ≥ 60 yrs. were recruited into the Division of Endocrinology of the Polytechnic University of Marche Region, Ancona (Italy). A protocol of questionnaires was constructed for data collection, and included domains such as physical activity, quality of life, socio-psychological aspects. The association of the latter variables with SF-36 Health Survey physical component (PCS-36) were evaluated in the whole sample. Multiple linear regression models were used to assess the effect of independent variables on PCS-36 and the physical subscales of SF-36. RESULTS: PCS-36 showed a lower score in the obese and overweight subjects than the normal weight group (post-hoc test, p < 0.001 and p < 0.05 respectively). Age, gender (male), Body Mass Index, years of education, Physical Activity Scale for the Elderly (PASE) total score, Hospital Anxiety and Depression Scale anxiety, Hospital Anxiety and Depression Scale depression, number of medications prescribed and number of diseases were included in the model. Negative and significant PCS-associated variables included depression (p = 0.009), BMI (p = 0.001), age in years (p = 0.007), whereas positive and significant PCS-associated independent variables were years of education (p = 0.022), physical activity (p = 0.026). BMI was negatively associated with all the physical subscales of SF-36 (p < 0.05). CONCLUSIONS: Research funding should be invested in the study of the benefits accruing from reducing obesity in the elderly.

Sexual dysfunctions in men affected by autoimmune Addison's disease before and after short-term gluco- and mineralocorticoid replacement therapy.

INTRODUCTION: There is evidence suggesting that autoimmune Addison's disease (AD) could be associated with sexual dysfunctions probably caused by gluco- and mineralocorticoid deficiency; however, no study has yet treated this subject in males. AIM: To evaluate male sexuality and psychological correlates in autoimmune AD before and after gluco- and mineralocorticoid replacement therapy. METHODS: Twelve subjects with a first diagnosis of autoimmune AD were studied before (baseline) and 2 months after (recovery phase) initiating hormone replacement therapy. MAIN OUTCOME MEASURES: Erectile function (EF), orgasmic function (OF), sexual desire (SD), intercourse satisfaction (IS), overall satisfaction (OS), depression, and anxiety were studied using a number of questionnaires (International Index of Erectile Function, Beck Depression Inventory, and Spielberger State-Trait Anxiety Inventory); clinical, biochemical, and hormone data were included in the analysis. RESULTS: At baseline, low values were found for EF, OF, SD, IS, and OS and high values for depression and anxiety; all of these parameters improved significantly in the recovery phase compared with baseline. EF variation between the two phases correlated significantly and positively with the variation of serum cortisol, urinary free cortisol, systolic blood pressure, and diastolic blood pressure and inversely with that of upright plasma renin activity. Multiple linear regression analysis using EF variation as dependent variable confirmed the relationship of the latter with variation of serum cortisol, urinary free cortisol, and upright plasma renin activity but not with variation of systolic and diastolic blood pressure. CONCLUSIONS: Our study showed that onset of autoimmune AD in males is associated with a number of sexual dysfunctions, all reversible after initiating replacement hormone therapy; cortisol and aldosterone deficiency seems to play an important role in the genesis of erectile dysfunction although the mechanism of their activity is not clear.

Corticotrophin-releasing hormone and desmopressin tests in the differential diagnosis between Cushing's disease and pseudo-Cushing state: a comparative study.

BACKGROUND: We recently proposed a new and effective way of interpreting human corticotrophin-releasing hormone (hCRH) and desmopressin (DDAVP) tests, for the differential diagnosis between Cushing's disease (CD) and pseudo-Cushing state (PC), based on the simultaneous analysis of ACTH and cortisol. OBJECTIVE: The study had the aims of comparing the diagnostic performance of the two tests and determining whether carrying out both tests was more beneficial than carrying out only one. PATIENTS AND MEASUREMENTS: We studied 30 CD, 18 PC and 12 control (CT) subjects: in these patients, hCRH test, DDAVP test, 24-h urinary free cortisol, serum cortisol after overnight 1-mg dexamethasone suppression test and serum cortisol circadian rhythm were performed. RESULTS: The hCRH test and the DDAVP test showed an identical and excellent diagnostic performance (sensitivity 96·6% and specificity 100% for both tests); moreover, the hCRH and DDAVP tests showed almost perfect diagnostic agreement (κ = 0·93; P < 0·05) with a significantly higher number of concordant diagnoses (58 cases of 60) than those resulting from all other possible combinations among the studied tests. Interestingly, there were no subjects in whom both hCRH and DDAVP tests gave a simultaneous misdiagnosis. CONCLUSIONS: Our study indicates that the hCRH and DDAVP tests have similar diagnostic performance and present excellent agreement, without giving simultaneous misdiagnosis in any subject. Because of these characteristics, the use of both tests offers the physician a valuable tool for those cases of hypercortisolism which are difficult to interpret.

Intrapituitary cytokines in Cushing's disease: do they play a role?

A large body of in vitro evidence shows that cytokines influence the hypothalamic-pituitary-adrenal axis both in physiological conditions and in Cushing's disease (CD). In order to study in vivo the role of intrapituitary cytokines in CD, we assayed two cytokines known for their action on the pituitary, i.e. interleukin-1 beta (IL-1ß) and interleukin-6 (IL-6), and also soluble interleukin-6 receptor (sIL-6R), important for the neural activities of IL-6, in a carefully selected sample of subjects affected by CD undergoing bilateral inferior petrosal sinus sampling. Similarly to ACTH, all cytokines basally showed a higher concentration in the ipsilateral sinus compared to the controlateral one and to that of peripheral blood; after CRH infusion, both ipsilaterally and controlaterally, IL-6 and sIL-6R values increased compared to basal ones, while IL-1ß increased significantly up to 5 min after CRH and then decreased significantly compared to basal values in subsequent measurements; peripherically no significant variations in the cytokines were observed after CRH. Again similarly to ACTH, the three cytokines presented a higher increase ipsilaterally than controlaterally; moreover all three interleukins in the ipsilateral sinuses showed positive and significant correlations between their basal value and that of basal ACTH. These findings allow us to hypothesize that the central production of IL-1ß and IL-6 could be involved in ACTH hypersecretion which occurs in CD: more specifically, we hypothesize that these cytokines are produced directly by the corticotroph adenoma and have the task of enhancing tumoral secretion of ACTH with an autocrine-paracrine mechanism.

Protective effect of leg fat against cardiovascular risk factors in obese premenopausal women.

BACKGROUND AND AIMS: While the relationship between abdominal fat and cardiovascular risk (CVR) factors is well established, the possible protective role of peripheral fat against these factors has received less attention, particularly in severely obese individuals. The principal aim of this study was to analyse the relationship, if any, among amount of leg fat, CVR factors and body mass index (BMI) in obese premenopausal women. METHODS AND RESULTS: Subjects were 80 obese premenopausal women. Body composition was measured by dual energy X-ray absorptiometry (DEXA); CVR factors (blood pressure, plasma lipids, glucose) were determined and anthropometric measurements (waist and hip circumferences) taken. In severely obese women (BMI>40 kg/m(2)) leg fat correlated negatively with CVR factors, whereas metabolic parameters were not significantly different from those of subjects with BMI<40 kg/m(2). CONCLUSIONS: Leg fat seems to play a protective role against CVR factors in severely obese premenopausal women.

Vitamin D and Male Sexual Function: A Transversal and Longitudinal Study.

BACKGROUND: The effects of vitamin D on sexual function are very unclear. Therefore, we aimed at evaluating the possible association between vitamin D and sexual function and at assessing the influence of vitamin D administration on sexual function. METHODS: We retrospectively studied 114 men by evaluating clinical, biochemical, and sexual parameters. A subsample (n = 41) was also studied longitudinally before and after vitamin D replacement therapy. RESULTS: In the whole sample, after performing logistic regression models, higher levels of 25(OH) vitamin D were significantly associated with high values of total testosterone and of all the International Index of Erectile Function (IIEF) questionnaire parameters. On the other hand, higher levels of total testosterone were positively and significantly associated with high levels of erectile function and IIEF total score. After vitamin D replacement therapy, total and free testosterone increased and erectile function improved, whereas other sexual parameters did not change significantly. At logistic regression analysis, higher levels of vitamin D increase (Δ-) were significantly associated with high values of Δ-erectile function after adjustment for Δ-testosterone. CONCLUSIONS: Vitamin D is important for the wellness of male sexual function, and vitamin D administration improves sexual function.

Vitamin D and cardiovascular disease: From atherosclerosis to myocardial infarction and stroke.

There continues to be interest in understanding the role of vitamin D in the pathogenesis, epidemiology and prevention of cardiovascular disease (CVD). In fact vitamin D deficiency has been associated to an increased risk of developing CVD given to the relationship between low vitamin D levels and obesity, diabetes mellitus, dyslipidaemia, endothelial dysfunction and hypertension. However, although vitamin D has been identified as a potentially important marker of CVD, the mechanisms through which vitamin D deficiency leads from endothelial dysfunction to myocardial infarction and stroke are not fully understood. Thus, the goal of this review is to provide an updated review of the literature on the basic science of how vitamin D may affect the cardiovascular system and in particular to analyze the role that vitamin D may have in the whole dynamic process from the initiation of endothelial dysfunction to the development of myocardial infarction and stroke.

Androgen receptor GGC repeat might be more involved than CAG repeat in the regulation of the metabolic profile in men.

The influence of androgen receptor (AR) GGC repeat polymorphism on the metabolic profile of men has been much less studied than the one of CAG tract polymorphism. Therefore, in this study, we looked for the association of GGC and CAG tract with cardiovascular risk factors in men. Ninety-eight men followed by our andrological unit were retrospectively reviewed. Clinical and biochemical parameters on cardiovascular risk were considered. AR CAG and GGC polymorphisms were studied. GGC triplets were found to be positively and significantly correlated with several cardiovascular risk factors. On the other hand, inverse and significant correlations of CAG triplets were found with insulin and HOMA. As expected, age was positively correlated with cardiovascular risk, whereas total testosterone was inversely correlated with metabolic profile. Estradiol was not found to be correlated with any of the metabolic parameters. In the total sample, multivariate linear regression analysis confirms the positive and independent association of GGC triplets with glycemia, glycated hemoglobin, total cholesterol, triglycerides and homeostasis model assessment of insulin resistance (HOMA), whereas CAG repeat length is negatively associated with insulin and HOMA. Such associations are also substantially confirmed in non-diabetic subjects, whereas in diabetic patients only the GGC tract seems to be involved in the metabolic profile regulation. Our work shows a relevant role for GGC repeat tract in conditioning male cardiovascular risk, thus rendering necessary a deeper analysis on the role of GGC polymorphism both from the molecular and the clinical point of view.