Circulating IL-8 levels are increased in patients with type 2 diabetes and associated with worse inflammatory and cardiometabolic profile

AIMS

Interleukin-8 (IL-8) is a chemokine involved in systemic immunity, macrophages infiltration and activation in adipose tissue and may play a significant role in the pathogenesis of type 2 diabetes (T2D) and atherosclerosis. Aims of this study were to evaluate circulating IL-8 levels in adult patients with T2D in comparison with non-diabetic subjects and to describe clinical and biochemical correlates of IL-8 concentration.

METHODS

For this cross-sectional study, we enrolled 79 consecutive T2D individuals referring to our diabetes outpatient clinics at Sapienza University of Rome, and 37 sex, age and BMI comparable non-diabetic subjects as a control group. Clinical parameters and medical history were recorded; fasting blood sampling was performed for biochemistry and for measuring serum IL-8, IL-6, TNF-α, CRP, adiponectin and 25(OH)vitamin D [25(OH)D] levels.

RESULTS

Patients with T2D exhibited significantly higher serum IL-8 levels than non-diabetic subjects (69.27 ± 112.83 vs. 16.03 ± 24.27 pg/mL, p < 0.001). In diabetic patients, increased IL-8 concentration correlated with higher IL-6 (p < 0.001), TNF-α (p = 0.02), FBG (p = 0.035), HbA1c (p = 0.04) and LDL-C (p = 0.04) and with lower adiponectin (p = 0.02) and 25(OH)D (p = 0.003) concentrations.

CONCLUSIONS

Patients with T2D display a marked elevation of circulating IL-8 levels which identify subjects with worse inflammatory, glycometabolic and lipid profile and lower vitamin D levels. Further studies are warranted for evaluating a possible role of IL-8 as a novel marker for risk stratification in T2D patients.

Testosterone insulin-like effects: an in vitro study on the short-term metabolic effects of testosterone in human skeletal muscle cells

PURPOSE

Testosterone by promoting different metabolic pathways contributes to short-term homeostasis of skeletal muscle, the largest insulin-sensitive tissue and the primary site for insulin-stimulated glucose utilization. Despite evidences indicate a close relationship between testosterone and glucose metabolism, the molecular mechanisms responsible for a possible testosterone-mediated insulin-like effects on skeletal muscle are still unknown.

METHODS

Here we used undifferentiated proliferating or differentiated human fetal skeletal muscle cells (Hfsmc) to investigate the short-term effects of testosterone on the insulin-mediated biomolecular metabolic machinery. GLUT4 cell expression, localization and the phosphorylation/activation of AKT, ERK, mTOR and GSK3β insulin-related pathways at different time points after treatment with testosterone were analyzed.

RESULTS

Independently from cells differentiation status, testosterone, with an insulin-like effect, induced Glut4-mRNA expression, GLUT4 protein translocation to the cytoplasmic membrane, while no effect was observed on GLUT4 protein expression levels. Furthermore, testosterone treatment modulated the insulin-dependent signal transduction pathways inducing a rapid and persistent activation of AKT, ERK and mTOR, and a transient inhibition of GSK3β. T-related effects were shown to be androgen receptor dependent.

CONCLUSION

All together our data indicate that testosterone through the activation of non-genomic pathways, participates in skeletal muscle glucose metabolism by inducing insulin-related effects.

"Metabolic and cardiovascular response to exercise in patients with type 1 diabetes"

PURPOSE

Physical activity is an effective therapeutic tool for cardiovascular risk prevention. However, exercise aerobic capacity of patients with type 1 diabetes (T1DM) has not been thoroughly investigated. Aim of the present study is to evaluate exercise aerobic capacity in patients with T1DM compared to a normal control population.

METHODS

This observational study included 17 T1DM patients and 17 matched healthy volunteers. Cardiopulmonary exercise test (CPET) was conducted on an electronically-braked cycle ergometer. Blood samples were collected for evaluation of glycemia and lactate levels.

RESULTS

Mean oxygen uptake at peak exercise (V'O_2,peak) was significantly lower in T1DM subjects (V'O_2,peak T1DM 2200 ± 132ml/min vs V'O_2,peak Healthy subjects of 2659 ± 120 ml/min p = 0.035). Cardiovascular response analysis did not show statistically significant differences. Respiratory exchange ratio (RER) was significantly higher in healthy subjects at peak exercise and at the first minute of recovery (p = 0.022, p = 0.024). Peak exercise lactate levels were significantly higher in healthy subjects. There was no statistical correlation between CPET results and diabetes-related parameters.

CONCLUSIONS

Patients affected by T1DM have a worse exercise tolerance than normal subjects. The two groups differed by RER which can be greatly influenced by the substrate type utilized to produce energy. Because of the impaired carbohydrate utilization, T1DM subjects may use a larger amount of lipid substrates, such hypothesis could be strengthened by the lower lactate levels found in T1DM group at peak exercise. The lack of correlation between exercise tolerance and disease-related variables suggests that the alterations found could be independent from the glycemic levels.

Influence of vitamin D levels on the cardiovascular profile of hypogonadal men

PURPOSE

A large body of evidence suggests a role for vitamin D in conditioning cardiovascular risk. Therefore, it can be hypothesized that vitamin D might also play a role in influencing the metabolic profile of hypogonadal men. In this work, we aimed at evaluating if any relationship exists between vitamin D levels and cardiovascular parameters in male hypogonadism.

METHODS

Hypogonadal patients attending our andrology unit were retrospectively reviewed. Clinical and biochemical parameters were evaluated.

RESULTS

103 patients were studied (51 non-diabetic and 52 diabetic subjects). Mean age of the whole sample was 65 years (standard error of the mean: 0.62). Significant correlations of age, total testosterone, parathyroid hormone (PTH), calcemia, and 25-OH vitamin D with the metabolic profile were found. In logistic regression models including age, total testosterone, PTH, calcemia and 25-OH vitamin D as independent variables, lower levels of 25-OH vitamin D were associated with high values of body mass index (BMI) [odds ratio (OR) 0.910, p 0.019], insulin (OR 0.918, p 0.034), homeostatic model assessment (HOMA) index (OR 0.918, p 0.030), total cholesterol (OR 0.819, p < 0.001), triglycerides (OR 0.820, p < 0.001), and low-density lipoprotein cholesterol (OR 0.923, p 0.034). In non-diabetic subjects, lower levels of 25-OH vitamin D were associated with high values of BMI, insulin, HOMA, triglycerides, systolic, and diastolic blood pressure. On the other hand, in diabetic subjects, lower levels of 25-OH vitamin D were associated with high values of total cholesterol and triglycerides.

CONCLUSIONS

Our work shows the influence of vitamin D on cardiovascular profile in male hypogonadism. This effect seems to be more relevant in non-diabetic subjects. If these data were to be confirmed, vitamin D assessment might become mandatory in the clinical evaluation of cardiovascular profile in male hypogonadism.

Erectile function recovery in men treated with phosphodiesterase type 5 inhibitor administration after bilateral nerve-sparing radical prostatectomy: a systematic review of placebo-controlled randomized trials with trial sequential analysis

The impact of phosphodiesterase type 5 inhibitor (PDE5I) treatment modality (on-demand vs. daily), PDE5I half-life and time from surgery to PDE5I prescription on the achievement of drug-assisted erectile function (EF) recovery is uncertain. We systematically reviewed published randomized clinical trials (RCTs). We performed meta-analyses of data on 2317 men treated with PDE5Is after nerve-sparing radical prostatectomy (NSRP). A PubMed and SCOPUS search was performed for trials published from 1 January 1969 to 30 June 2016. PDE5Is are effective in achieving drug-assisted recovery of erectile function (EF). From a statistical standpoint, these studies were subjected to Trial Sequential Analysis to determine whether the pooled data were adequately powered to verify the study outcomes. On-demand treatment with PDE5Is was significantly better than daily treatment in recovering drug-assisted EF. This effect was maintained even when the drugs were stratified according with half-life. Although not based on head-to-head trials, Avanafil used on-demand was the most effective PDE5I in recovering drug-assisted EF. Whereas tadalafil was equally effective when used both on-demand and daily, vardenafil significantly improved drug-assisted EF recovery only when used on-demand. The start of PDE5I treatment six months or more after surgery compared to treatment started earlier did not negatively affect the rate of drug-assisted EF recovery or the possibility to have successful intercourse based on the Sexual Encounter Profile question-3 (SEP-3). Current trials do not support the hypothesis that PDE5I use recovers drug-unassisted EF, although chronic low-dose tadalafil administration may help to preserve erectile tissue integrity. Potential shortcomings in the trials design may partially explain these disappointing results and several questions concerning the recovery of drug-unassisted EF remain unanswered. Thus, there is a need for well-designed new RCTs requiring changes in the timing of PDE5I administration as well as in the dose and the treatment duration.

Effects of daily tadalafil on lower urinary tract symptoms in young men with multiple sclerosis and erectile dysfunction: a pilot study

PURPOSE

Men affected by multiple sclerosis often experience neurogenic overactive bladder (OAB), lower urinary tract symptoms and erectile dysfunction (ED). The aim of the study was to investigate modifications of urinary and sexual functions after administration of daily tadalafil (TAD) 5 mg.

METHODS

Twenty men were enrolled in a single-blind, 4-week prospective study while 10 men without treatment served as controls. Primary outcomes were changes from baseline of International Prostate Symptom (IPSS), OAB questionnaire (OAB-q-short form) and International Index of Erectile Function (IIEF-5) scores. To evaluate the influence of bladder filling on somatic reflexes, we studied variations of the H-reflex evoked by electrical stimuli applied to the tibial nerve at the popliteal fossa and recorded from the soleus muscle. Also testosterone/estradiol (T/E) ratio was measured before and after treatment.

RESULTS

In TAD group, an improvement in IPSS (p < 0.001), OAB-q (p < 0.001) and IIEF-5 (p < 0.001) scores was found. Also, an increase in Q _max (p < 0.01) and T/E ratio (p < 0.01) was found with a concomitant reduction in post-void residual volume (p < 0.001) without any changes in the H-reflex.

CONCLUSIONS

The study demonstrates for the first time that daily TAD in patients with multiple sclerosis improves storage symptoms, post-void residual volume, steroid hormone pattern and ED without urodynamic changes.

Cross-cultural and socio-demographic correlates of homophobic attitude among university students in three European countries

PURPOSE

The aim of this study was to investigate homophobic attitudes in three European countries: Italy, Albania, and Ukraine. One thousand and forty-eight students were recruited in Italian (n = 766), Albanian (n = 180), and Ukrainian (n = 102) university centers.

METHODS

A socio-demographic questionnaire and Homophobia Scale (HS) were administered by our staff.

RESULTS

Cross-cultural and significant differences among Italian, Albanian, and Ukrainian students were found on the Homophobia Scale (HS; Italy: mean = 22.26 ± 16.73; Albania: mean = 38.15 ± 17.28; Ukraine: mean = 59.18 ± 16.23). The analysis of socio-demographic characteristics revealed that the male gender emerged as main predictor of homophobic attitude in all the three countries, although also a conservative political orientation and the religious belief predict higher homophobia levels in Italy and Albania, particularly.

CONCLUSIONS

This study revealed that in these European countries assessed, attitudes toward homosexuality are different. Ukrainians display higher levels of homophobia than Albanians and Italians, confirming the central role of cultural differences in homophobic attitudes. Nevertheless, some socio-demographic aspects such as identification as male have a similar influence on homophobic attitudes in all assessed populations.

Supra-physiological rhGH administration induces gender-related differences in the hypothalamus-pituitary-thyroid (HPT) axis in healthy individuals

PURPOSE

The use of recombinant human growth hormone (rhGH) is a common habit among athletes. While the effects of rhGH administration have been described with contrasting results in males, no data exist in females to date. The aim of the present study was to evaluate the effects of rhGH administration on TSH, FT₄ and FT₃ levels and the time requested to return to baseline values after treatment withdrawal.

METHODS

Twenty-one healthy trained male and female athletes were treated with 0.03 mg rhGH/kg body mass 6 days/week for 3 weeks. We collected blood samples immediately before the first daily rhGH administration, at 3, 4, 8, 15 and 21 days of treatment and at 3 and 9 days after rhGH withdrawal.

RESULTS

In males, rhGH administration induced a significant (p < 0.01) early and stable TSH decrease and IGF-I increase, and a delayed FT₄ reduction without FT₃ modification, suggesting a central regulatory mechanism. In females, rhGH administration induced a significant (p < 0.01) early and transient TSH decrease and IGF-I increase, and a transient reduction in FT₄ without any changes in FT₃ concentrations. rhGH withdrawal was associated with a prompt normalization of TSH and FT₄ levels in males, while in females the effects of rhGH treatment had already disappeared during the last period of treatment.

CONCLUSION

We suggest that rhGH inhibits TSH at central level both in males and females. The pattern of normalization was different in the two genders probably due to gonadal steroids modulation on GH-IGF-I axis.

Recommendations for treatment of hypothyroidism with levothyroxine and levotriiodothyronine: a 2016 position statement of the Italian Society of Endocrinology and the Italian Thyroid Association

Levothyroxine (L-T4) is recommended as lifelong replacement therapy for hypothyroidism. Recent clinical and experimental data support the addition of levotriiodothyronine (L-T3) treatment in some selected hypothyroid patients when their symptoms persist and their quality of life remains impaired despite adequate L-T4 monotherapy. An increase in L-T3 prescriptions has been recently observed in Italy due to availability of different L-T3 formulations, making it possible to clinicians to prescribe L-T3 alone or in combination with L-T4. The aim of the present position statement was to define the correct clinical indications, schedule, duration of treatment and contraindications of combined treatment with L-T4 and L-T3 in hypothyroid patients in an attempt to guide clinicians and to avoid potential adverse effects of overtreatment.

Circulating SIRT1 inversely correlates with epicardial fat thickness in patients with obesity

BACKGROUND AND AIM

Obesity is increasing worldwide and is related to undesirable cardiovascular outcomes. Epicardial fat (EF), the heart visceral fat depot, increases with obesity and correlates with cardiovascular risk. SIRT1, an enzyme regulating metabolic circuits linked with obesity, has a cardioprotective effect and is a predictor of cardiovascular events. We aimed to assess the relationship of EF thickness (EFT) with circulating SIRT1 in patients with obesity.

METHODS AND RESULTS

Sixty-two patients affected by obesity and 23 lean controls were studied. Plasma SIRT1 concentration was determined by enzyme-linked immunosorbent assay (ELISA). EFT was measured by echocardiography. Body mass index (BMI), waist circumference, heart rate (HR), blood pressure, and laboratory findings (fasting glucose, insulin, HbA1c, cholesterol, and triglycerides) were assessed. SIRT1 was significantly lower (P = 0.002) and EFT was higher (P < 0.0001) in patients with obesity compared with lean controls. SIRT1 showed a negative correlation with EFT and HR in the obesity group (ρ = -0.350, P = 0.005; ρ = -0.303, P = 0.008, respectively). After adjustment for obesity-correlated variables, multiple linear regression analysis showed that EFT remained the best correlate of SIRT1 (β = -0.352, P = 0.016).

CONCLUSIONS

Circulating SIRT1 correlates with the visceral fat content of the heart. Serum SIRT1 levels might provide additional information for risk assessment of coronary artery disease in patients with obesity.

Consumption of extra-virgin olive oil rich in phenolic compounds improves metabolic control in patients with type 2 diabetes mellitus: a possible involvement of reduced levels of circulating visfatin

AIM

Phenolic compounds naturally contained in extra-virgin olive oil (EVOO) have demonstrated anti-inflammatory and antioxidant properties. The present study aimed at evaluating the effects of a polyphenol-rich extra-virgin olive oil (EVOO) (high-polyphenol EVOO, HP-EVOO) on the metabolic control and the production of specific pro-/anti-inflammatory adipokines in overweight patients with type 2 diabetes mellitus (T2D).

METHODS

Eleven overweight T2D patients not in treatment with insulin were invited to follow their habitual diet for a total of 8 weeks. During the first 4 weeks (wash-out period), they were asked to consume refined olive oil (ROO, polyphenols not detectable) and then to replace ROO with HP-EVOO (25 mL/day, 577 mg of phenolic compounds/kg) for the remaining 4 weeks. Anthropometric parameters, fasting glycaemia, glycated haemoglobin (HbA1c), high-sensitive C-reactive protein, plasma lipid profile, liver function and serum levels of TNF-α, IL-6, adiponectin, visfatin and apelin were assessed at the end of each 4-week period.

RESULTS

HP-EVOO consumption significantly reduced fasting plasma glucose (P = 0.023) and HbA1c (P = 0.039) levels as well as BMI (P = 0.012) and body weight (P = 0.012). HP-EVOO ingestion determined a reduction in serum level of aspartate aminotransferase (AST, P = 0.0056) and alanine aminotransferase (ALT, P = 0.024). Serum visfatin levels strongly decreased after HP-EVOO ingestion (P = 0.0021).

CONCLUSIONS

Daily consumption of polyphenol-rich EVOO might improve metabolic control and circulating inflammatory adipokines profile in overweight T2D patients.

Diagnostic value of qualitative and strain ratio elastography in the differential diagnosis of non-palpable testicular lesions

The purpose of this study was to evaluate prospectively the accuracy of qualitative and strain ratio elastography (SE) in the differential diagnosis of non‐palpable testicular lesions. The local review board approved the protocol and all patients gave their consent. One hundred and six patients with non‐palpable testicular lesions were consecutively enrolled. Baseline ultrasonography (US) and SE were correlated with clinical and histological features and ROC curves developed for diagnostic accuracy. The non‐palpable lesions were all ≤1.5 cm; 37/106 (34.9%) were malignant, 38 (35.9%) were benign, and 31 (29.2%) were non‐neoplastic. Independent risk factors for malignancy were as follows: size (OR 17.788; p = 0.002), microlithiasis (OR 17.673, p < 0.001), intralesional vascularization (OR 9.207, p = 0.006), and hypoechogenicity (OR, 11.509, p = 0.036). Baseline US had 89.2% sensitivity (95% CI 74.6–97.0) and 85.5% specificity (95% CI 75.0–92.8) in identifying malignancies, and 94.6% sensitivity (95% CI 86.9–98.5) and 87.1% specificity (95% CI 70.2–96.4) in discriminating neoplasms from non‐neoplastic lesions. An elasticity score (ES) of 3 out of 3 (ES3, maximum hardness) was recorded in 30/37 (81.1%) malignant lesions (p < 0.001). An intermediate score of 2 (ES2) was recorded in 19/38 (36.8%) benign neoplastic lesions and in 22/31 (71%) non‐neoplastic lesions (p = 0.005 and p = 0.001 vs. malignancies). None of the non‐neoplastic lesions scored ES3. Logistic regression analysis revealed a significant association between ES3 and malignancy (χ² = 42.212, p < 0.001). ES1 and ES2 were predictors of benignity (p < 0.01). Overall, SE was 81.8% sensitive (95% CI 64.8–92.0) and 79.1% specific (95% CI 68.3–88.4) in identifying malignancies, and 58.6% sensitive (95% CI 46.7–69.9) and 100% specific (95% CI 88.8–100) in discriminating non‐neoplastic lesions. Strain ratio measurement did not improve the accuracy of qualitative elastography. Strain ratio measurement offers no improvement over elastographic qualitative assessment of testicular lesions; testicular SE may support conventional US in identifying non‐neoplastic lesions when findings are controversial, but its added value in clinical practice remains to be proven.

Activated c-Kit receptor in the heart promotes cardiac repair and regeneration after injury

The role of endogenous c-Kit receptor activation on cardiac cell homeostasis and repair remains largely unexplored. Transgenic mice carrying an activating point mutation (TgD814Y) in the kinase domain of the c-Kit gene were generated. c-Kit^TgD814Y receptor was expressed in the heart during embryonic development and postnatal life, in a similar timing and expression pattern to that of the endogenous gene, but not in the hematopoietic compartment allowing the study of a cardiac-specific phenotype. c-Kit^TgD814Y mutation produced a constitutive active c-Kit receptor in cardiac tissue and cells from transgenic mice as demonstrated by the increased phosphorylation of ERK1/2 and AKT, which are the main downstream molecular effectors of c-Kit receptor signaling. In adult transgenic hearts, cardiac morphology, size and total c-Kit⁺ cardiac cell number was not different compared with wt mice. However, when c-Kit^TgD814Y mice were subjected to transmural necrotic heart damage by cryoinjury (CI), all transgenic survived, compared with half of wt mice. In the sub-acute phase after CI, transgenic and wt mice showed similar heart damage. However, 9 days after CI, transgenic mice exhibited an increased number of c-Kit⁺CD31⁺ endothelial progenitor cells surrounding the necrotic area. At later follow-up, a consistent reduction of fibrotic area, increased capillary density and increased cardiomyocyte replenishment rate (as established by BrdU incorporation) were observed in transgenic compared with wt mice. Consistently, CD45⁻c-Kit⁺ cardiac stem cells isolated from transgenic c-Kit^TgD814Y mice showed an enhanced endothelial and cardiomyocyte differentiation potential compared with cells isolated from the wt. Constitutive activation of c-Kit receptor in mice is associated with an increased cardiac myogenic and vasculogenic reparative potential after injury, with a significant improvement of survival.

The vitamin D receptor (VDR) gene rs11568820 variant is associated with type 2 diabetes and impaired insulin secretion in Italian adult subjects, and associates with increased cardio-metabolic risk in children

BACKGROUND AND AIMS

1α,25-dihydroxyvitamin-D3, the biologically active vitamin D, plays a central role in several metabolic pathways through the binding to the vitamin D receptor (VDR). VDR has been shown to be involved in cardiovascular diseases, cancer, autoimmunity and type 2 diabetes mellitus (T2DM). Several polymorphisms in the VDR gene have been described. Among these, the rs11568820 G-to-A nucleotide substitution was found to be functional, modulating the transcription of the VDR gene. Objective of this study was to perform an association study between rs11568820 polymorphism and T2DM in a cohort of Italian adults with T2DM and in non-diabetic controls. To add further insight into the role of VDR gene we explored whether this association begins early in life in overweight/obese children, or becomes manifest only in adulthood.

METHODS AND RESULTS

As many as 1788 adults and 878 children were genotyped for the rs11568820 polymorphism. All participants underwent oral glucose tolerance tests (OGTT), with measurement of glucose and insulin levels. Indices of insulin-resistance and secretion were also calculated. The AA genotype was significantly more frequent in adults with T2DM compared to controls (7.5% vs. 4.6%, P = 0.037), and conferred a higher risk of T2DM (ORHom = 1.69C.I. = [1.13-2.53], P = 0.011). In the adult cohort, rs11568820 was also associated with reduced indices of β-cell insulin secretion. In children, the AA genotype was associated with 2 h high-normal glucose, a marker of cardio-metabolic risk.

CONCLUSIONS

Our study demonstrates for the first time that VDR gene AA carriers have higher risk of T2DM and impaired insulin secretion. In children, the association between AA homozygous and high-normal 2h glucose suggests that mild alterations associated with this genotype may appear early in life.

Vitamin D protects endothelial cells from irradiation-induced senescence and apoptosis by modulating MAPK/SirT1 axis

PURPOSE

Radiotherapy toxicity is related to oxidative stress-mediated endothelial dysfunction. Here, we investigated on radioprotective properties of Vitamin D (Vit.D) on human endothelial cells (HUVEC).

METHODS

HUVEC, pre-treated with Vit.D, were exposed to ionizing radiation (IR): ROS production, cellular viability, apoptosis, senescence and western blot for protein detection were performed. The role of MAPKs pathway was investigated by using U0126 (10 μM) MEKs/ERKs-, SB203580 (2.5 μM) p38-inhibitor or by over/expressing MKK6 p38-upstream activator.

RESULTS

Vit.D reduced IR-induced ROS production protecting proliferating and quiescent HUVEC from cellular apoptosis or senescence, respectively, by regulating MAPKs pathways. In proliferating HUVEC, Vit.D prevented IR-induced apoptosis by activating ERKs while in quiescent HUVEC counteracted IR-induced senescence by inhibiting the p38-IR-induced activation. MEKs&ERKs inhibition in proliferating or MKK6/mediated p38 activation in quiescent HUVEC, respectively, reverted anti-apoptotic or anti-senescent Vit.D properties. SirT1 protein expression levels were up-regulated by Vit.D. ERKs inhibition blocked Vit.D-induced SirT1 protein up-regulation in proliferating cells. In quiescent HUVEC cells, p38 inhibition counteracted the IR-induced SirT1 protein down-regulation, while MKK6 transfection abrogated the Vit.D positive effects on SirT1 protein levels after irradiation. SirT1 inhibition by sirtinol blocked the Vit.D radioprotective effects.

CONCLUSION

Vit.D protects HUVEC from IR induced/oxidative stress by positively regulating the MAPKs/SirT1 axis.

Acute endothelial response to testosterone gel administration in men with severe hypogonadism and its relationship to androgen receptor polymorphism: a pilot study

PURPOSE

Testosterone (T) exerts different effects on the cardiovascular system. Despite this knowledge, the acute vascular effect of androgen remains still poorly understood.

METHODS

We investigated the acute effects of T on vascular function in ten men (18-40 years age) with hypogonadism and severe hypotestosteronemia [serum total testosterone (TT) = 0.6 ± 0.3 ng/mL]. In a 4-day double-blind, randomized, placebo-controlled crossover study, we administered 80 mg daily dose of transdermal-T gel (TG) and evaluated endothelial variations with Endopat2000 (reactive hyperemia index, RHI and the augmentation index, AI); also, CAG repeat polymorphism in exon 1 of the androgen receptor gene was investigated.

RESULTS

After TG administration, RHI significantly improved at 4 h (p < 0.05), while AI improvement was recorded at 4 and 96 h, also when adjusted for heart rate (AI@75; p < 0.01 and p < 0.001, respectively). Direct relationships between ΔT, ΔDHT and ΔRHI variations (r = 0.37, p < 0.01; r = 0.17, p < 0.05, respectively) as well as between "CAG repeats" length and ΔLnRHI at 96 h (p < 0.03, r (2) = 0.47) were found. An inverse relationship between ΔT and ΔAI (p < 0.01, r = -0.35) and ΔAI@75 (p < 0.01, r = -0.38) were found.

CONCLUSION

Administration of TG causes an acute vasodilation and improves arterial stiffness probably due to non-genomic actions of T. Endothelial vasodilatory response was more pronounced depending on higher plasma TT and DHT levels attained. Clinical implications in elderly frail populations are discussed.

Tadalafil modulates aromatase activity and androgen receptor expression in a human osteoblastic cell in vitro model

PURPOSE

Phosphodiesterase type-5 inhibitor (PDE5i) tadalafil administration in men with erectile dysfunction is associated with increased testosterone/estradiol ratio, leading to hypothesize a potential increased effect of androgen action on target tissues. We aimed to characterize, in a cellular model system in vitro, the potential modulation of aromatase and sex steroid hormone receptors upon exposure to tadalafil (TAD).

METHODS

Human osteoblast-like cells SAOS-2 were chosen as an in vitro model system since osteoblasts are target of steroid hormones. Cells were tested for viability upon TAD exposure, which increased cell proliferation. Then, cells were treated with/without TAD for several times to evaluate potential modulation in PDE5, aromatase (ARO), androgen (AR) and estrogen (ER) receptor expression.

RESULTS

Osteoblasts express significant levels of both PDE5 mRNA and protein. Exposure of cells to increasing concentrations of TAD (10(-8)-10(-7) M) decreased PDE5 mRNA and protein expression. Also, TAD inhibited ARO mRNA and protein expression leading to an increase in testosterone levels in the supernatants. Interestingly, TAD increased total AR mRNA and protein expression and decreased ERα, with an increased ratio of AR/ER, suggesting preferential androgenic vs estrogenic pathway activation.

CONCLUSIONS

Our results demonstrate for the first time that TAD decreases ARO expression and increases AR protein expression in human SAOS-2, strongly suggesting a new control of steroid hormones pathway by PDE5i. These findings might represent the first evidence of translational actions of PDE5i on AR, which leads to hypothesize a growing relevance of this molecule in men with prostate cancer long-term treated with TAD for sexual rehabilitation.

Phosphodiesterase type 5 inhibitors: back and forward from cardiac indications

PDE5 inhibitors (PDE5i) are widely known as treatment for erectile dysfunction (ED). This favorable action has emerged as a "side effect" from pioneering studies when PDE5i have been originally proposed as treatment for coronary artery disease (CAD). PDE5i showed marginal benefits for CAD treatment; although disappointing for that indication, they improved systemic and pulmonary vasodilation and ameliorated general endothelial function. Therefore, PDE5i have been approved and licensed also for pulmonary artery hypertension (PAH), besides ED. Nowadays, fine-tuned biomolecular mechanisms of PDE5i are well recognized to be beneficial onto myocardial contractility and geometry, to reduce tissue fibrosis, hypertrophy and apoptosis. PDE5i consistently exert benefits on heart failure, infarct, cardiomyopathy. The concept that PDE5i likely blunt Th1-driven inflammatory processes, which shift the homeostatic balance from health to disease, has emerged; PDE5i seem to decrease the release of active biomolecules from cells to tissues interested by inflammation. In this view, following clinical and basic research progresses, PDE5i can be undoubtedly "re-allocated" for cardiac indications and, hopefully, they could be approved as therapeutic tools to treat and prevent heart disease. This review aims to summarize PDE5i different clinical applications, from past to present and future, focusing on their potential power as treatment for cardiac diseases.

The SNP rs9677 of VPAC1 gene is associated with glycolipid control and heart function in female patients with type 2 diabetes: A follow-up study

BACKGROUND AND AIMS

In a previous study, the single-nucleotide polymorphism (SNP) rs9677, mapped in the 3'-UTR of vasoactive intestinal peptide receptor 1 (VPAC1) gene, was found to be associated with type 2 diabetes (T2D) in Caucasian women. Moreover, the CC genotype correlated with a worse glycolipid profile. The objectives of this study were to confirm this correlation and assess the prevalence of coronary artery disease (CAD) in the previously investigated diabetic women after a follow-up of 4.6 years.

METHODS AND RESULTS

A total of 143 women with T2D, with 53 carrying the CC genotype (age: 71.7 ± 7.4 years, diabetes duration: 17.2 ± 9.9 years) and 90 carrying the CT + TT genotypes (age: 69.4 ± 8.8 years, diabetes duration: 14.3 ± 8.2 years), were followed up for 4.6 ± 1.8 years. At follow-up, the clinical and haematochemical parameters were analysed. Twelve-lead electrocardiography, Doppler echocardiography and the percentage of patients with acute myocardial infarction (AMI) or of those subjected to coronary angioplasty and coronary artery bypass surgery were evaluated. At follow-up, there was no significant difference in terms of the clinical and haematochemical parameters between the two groups. However, despite a significantly increased use of statin therapy, no significant improvement in the LDL cholesterol levels was observed in CC female patients unlike those with CT + TT (P = 0.02). Moreover, the CC female patients presented a significantly higher percentage of echocardiographic abnormalities (P = 0.035), especially left ventricular (LV) diastolic dysfunction (P = 0.04).

CONCLUSIONS

The rs9677 CC genotype could be correlated with a reduced response to statin therapy and seems to be involved in diabetes cardiomyopathy in female patients with T2D.

Diabetes Mellitus-Associated Functional Hypercortisolism Impairs Sexual Function in Male Late-Onset Hypogonadism

Functional hypercortisolism is generated by conditions able to chronically activate hypothalamic-pituitary-adrenal axis and has been proven to have a negative role in several complications. However, no study has evaluated the possible influence of diabetes mellitus-associated functional hypercortisolism on male hypogonadism and sexual function. We aimed to identify any association of hypothalamic-pituitary-adrenal axis dysregulation measures with testosterone and sexual function in men simultaneously affected by diabetes mellitus and late-onset hypogonadism. Fifteen diabetes mellitus and late-onset hypogonadism subjects suffering from functional hypercortisolism and fifteen diabetes mellitus and late-onset hypogonadism subjects who were free of functional hypercortisolism were retrospectively reviewed. Clinical, hormonal, and sexual parameters were considered. Hypercortisolemic subjects showed higher values of body mass index, waist, and glycated hemoglobin and lower ones of testosterone compared to normocortisolemic ones. All sexual parameters, except for orgasmic function, were significantly worse in hypercortisolemic than in normocortisolemic subjects. Hypercortisolemic patients showed higher values of cortisol after dexamethasone and urinary free cortisol as well as a lesser ACTH response after corticotropin releasing hormone test (ACTH area under curve) compared to normocortisolemic ones. No significant association was found at Poisson regression analysis between hormonal and sexual variables in normocortisolemic patients. In hypercortisolemic subjects, negative and significant associations of cortisol response after corticotropin releasing hormone (cortisol area under curve) with erectile function (β: -0.0008; p: 0.015) and total international index of erectile function score (β: -0.0006; p: 0.001) were evident. This study suggests for the first time the impairing influence of the dysregulated hypothalamic-pituitary-adrenal axis on sexual function in diabetes mellitus-associated late-onset hypogonadism.