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Introduction: Galectin-3 is a pro-fibrotic β-galactoside binding lectin highly expressed in fibrotic liver and implicated in hepatic fibrosis. Selvigaltin (previously known as GB1211) is a novel orally active galectin-3 small molecule inhibitor that has high affinity for galectin-3 (human KD = 25 nM; rabbit KD = 12 nM) and high oral bioavailability in rabbits and man. In this study the efficacy of selvigaltin was investigated in a high fat diet (HFD) rabbit model of metabolic-associated steatohepatitis (MASH). Methods: Male New Zealand White rabbits were individually caged under standard conditions in a temperature and humidity-controlled room on a 12 h light/darkness cycle. After 1 week of regular diet (RD), rabbits were randomly assigned for 8 or 12 weeks to different groups: RD/vehicle, RD/selvigaltin, HFD (8 weeks), HFD/vehicle and HFD/selvigaltin (0.3, 1.0, 5.0 or 30 mg/kg selvigaltin with vehicle/selvigaltin p.o. dosed therapeutically q.d. 5 days per week from week 9 or 12). Liver inflammation, steatosis, ballooning, and fibrosis was measured via blood metabolic markers, histomorphological evaluation [Oil Red O, Giemsa, Masson's trichome, picrosirius red (PSR) and second harmonic generation (SHG)], and mRNA and protein expression. Results: Steatosis, inflammation, ballooning, and fibrosis were all increased from RD to HFD/vehicle groups. Selvigaltin demonstrated target engagement by significantly decreasing galectin-3 levels in the liver as measured via immunohistochemistry and mRNA analysis. Selvigaltin dose-dependently reduced biomarkers of liver function (AST, ALT, bilirubin), inflammation (cells foci), and fibrosis (PSR, SHG), as well as decreasing the mRNA and protein expression of several key inflammation and fibrosis biomarkers (e.g., IL6, TGFβ3, SNAI2, collagen). Doses of 1.0 or 5.0 mg/kg demonstrated consistent efficacy across most biological endpoints supporting the current clinical doses of selvigaltin being investigated in liver disease. Discussion: Selvigaltin significantly reduced hepatic inflammation and fibrosis in an HFD rabbit model of MASH following therapeutic dosing for 4 weeks in a dosedependent manner. These data support the human selvigaltin dose of 100 mg b.i.d. that has been shown to reduce key liver biomarkers during a clinical study in liver cirrhosis. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) is known to promote vascular endothelial growth factor (VEGF)-stimulated permeability and angiogenesis. However, effector molecules that operate downstream of NO in this pathway remain poorly characterized. Herein, we determined the effect of soluble guanylyl cyclase (sGC) inhibition on VEGF responses in vitro and in vivo. Treatment of endothelial cells (EC) with VEGF stimulated eNOS phosphorylation and cGMP accumulation; pretreatment with the sGC inhibitor 4H-8-bromo-1,2,4-oxadiazolo(3,4-d)benz(b)(l,4)oxazin-1-one (NS-2028) blunted cGMP levels without affecting VEGF-receptor phosphorylation. Incubation of cells with NS-2028 blocked the mitogenic effects of VEGF. In addition, cells in which sGC was inhibited exhibited no migration and sprouting in response to VEGF. To study the mechanisms through which NS-2028 inhibits EC migration, we determined the effects of alterations in cGMP levels on p38 MAPK. Initially, we observed that inhibition of sGC attenuated VEGF-stimulated activation of p38. In contrast, the addition of 8-Br-cGMP to EC stimulated p38 phosphorylation. The addition of cGMP elevating agents (BAY 41-2272, DETA NO and YC-1) enhanced EC migration. To test whether sGC also mediated the angiogenic effects of VEGF in vivo, we used the rabbit cornea assay. Animals receiving NS-2028 orally displayed a reduced angiogenic response to VEGF. As increased vascular permeability occurs prior to new blood vessel formation, we determined the effect of NS-2028 in vascular leakage. Using a modified Miles assay, we observed that NS-2028 attenuated VEGF-induced permeability. Overall, we provide evidence that sGC mediates the angiogenic and permeability-promoting activities of VEGF, indicating the significance of sGC as a downstream effector of VEGF-triggered responses. cGMP; vessels: sprouting; leakage; p38 doi:10.1152/ajpregu.00222.2009

Human bladder contraction mainly depends on [Ca.sup.2+] influx via L-type voltage-gated [Ca.sup.2+] channels and on RhoA/Rho kinase contractile signaling, which is upregulated in overactive bladder (OAB). Elocalcitol is a vitamin D receptor agonist inhibiting RhoA/Rho kinase signaling in rat and human bladder. Since in the normal bladder from Sprague-Dawley rats elocalcitol treatment delayed the carbachol-induced contraction without changing maximal responsiveness and increased sensitivity to the L-type [Ca.sup.2+] channel antagonist isradipine, we investigated whether elocalcitol upregulated L-type [Ca.sup.2+] channels in human bladder smooth muscle cells (hBCs). In hBCs, elocalcitol induced a rapid increase in intracellular [[Ca.sup.2+]], which was abrogated by the L-type [Ca.sup.2+] channel antagonist verapamil. Moreover, hBCs exhibited L-type voltage-activated [Ca.sup.2+] currents ([I.sub.Ca]), which were selectively blocked by isradipine and verapamil and enhanced by the selective L-type agonist BAY K 8644. Addition of elocalcitol ([10.sup.-7] M) increased L-type [I.sub.Ca] size and specific conductance by inducing faster activation and inactivation kinetics than control and BAY K 8644, while determining a significant negative shift of the activation and inactivation curves, comparable to BAY K 8644. These effects were strengthened in long-term treated hBCs with elocalcitol ([10.sup.-8] M, 48 h), which also showed increased mRNA and protein expression of pore-forming L-type [[alpha]sub.IC]-subunit. In the bladder from Sprague-Dawley rats, BAY K 8644 induced a dose-dependent increase in tension, which was significantly enhanced by elocalcitol treatment (30[micro]g*[kg.sup.-1]*[day.sup.-1], 2 wk). In conclusion, elocalcitol upregulated [Ca.sup.2+] entry through L-type [Ca.sup.2+] channels in hBCs, thus balancing its inhibitory effect on RhoA/Rho kinase signaling and suggesting its possible efficacy for the modulation of bladder contractile mechanisms. vitamin D analogue; human bladder smooth muscle cells; voltage-gated calcium channel; overactive bladder

Catecholamines have been shown to be involved in vascular remodeling through the stimulation of [[alpha].sub.1]-adrenoceptors ([[alpha].sub.1]-ARs). Recently, it has been demonstrated that catecholamines can stimulate angiogenesis in pathological conditions, even if the mechanisms and the AR subtypes involved still remain unclear. We investigated the influence of hypoxia (3% [O.sub.2]) on the ability of picomolar concentrations of phenylephrine (PHE), which are unable to induce any vascular contraction, to induce atrophic effect in human endothelial cells through stimulation of the [[alpha].sub.1D]-subtype ARs. PHE, at picomolar concentrations, significantly promoted pseudocapillary formation from fragments of human mature vessels in vitro. Exposure to hypoxia significantly potentiated this effect, which was inhibited by the selective [[alpha].sub.1D]-AR antagonist BMY-7378 and by the nitric oxide synthase inhibitor L-NAME, suggesting that [[alpha].sub.1D]-ARs were involved in this effect through activation of the nitric oxide pathway. Proliferation and migration of HUVEC were also affected by picomolar PHE concentrations. Again, these effects were significantly potentiated in cells exposed to hypoxia and were inhibited by BMY-7378 and by [N.sup.G]-nitro-L-arginine methyl ester. Conversely, the [[alpha].sub.1A]-AR-selective antagonist (S)-(+)-niguldipine hydrochloride and the [[alpha].sub.1B]-AR antagonist chloroethylclonidine dihydrochloride did not modify endothelial cell migration and proliferation in response to PHE. These results demonstrate that the stimulation of [[alpha].sub.1D]-ARs, triggered by picomolar PHE concentrations devoid of any contractile vascular effects, induces a proangiogenic phenotype in human endothelial cells that is enhanced in a hypoxic environment. The role of [[alpha].sub.1D]-ARs may become more prominent in the adaptive responses to hypoxic vasculature injury. vascular remodeling; low oxygen tension; endothelial cell growth and migration; catecholamines; nitric oxide

Vessel wall remodeling is a complex phenomenon in which the loss of differentiation of vascular smooth muscle cells (VSMCs) occurs. We investigated the role of rat macrophage chemoattractant protein (MCP)-1 on rat VSMC proliferation and migration to identify the mechanism(s) involved in this kind of activity. Exposure to very low concentrations (1-100 pg/ml) of rat MCP-1 induced a significant proliferation of cultured rat VSMCs assessed as cell duplication by the counting of total cells after exposure to test substances. MCP-1 stimulated VSMC proliferation and migration in a two-dimensional lateral sheet migration of adherent cells in culture. Endogenous vascular endothelial growth factor-A (VEGF-A) was responsible for the mitogenic activity of MCP-1, because neutralizing anti-VEGF-A antibody inhibited cell proliferation in response to MCP-1. On the contrary, neutralizing anti-fibroblast growth factor-2 and anti-platelet-derived growth factor-bb antibodies did not affect VSMC proliferation induced by MCP-1. RT-PCR and Western blot analyses showed an increased expression of either mRNA or VEGF-A protein after MCP-1 activation (10-100 pg/ml), whereas no fins-like tyrosine kinase (Flt)-1 receptor upregulation was observed. Because we have previously demonstrated that hypoxia (3% [O.sub.2]) can enhance VSMC proliferation induced by VEGF-A through Flt-1 receptor upregulation, the effects of hypoxia on the response of VSMCs to MCP-1 were investigated. Severe hypoxia (3% [O.sub.2]) potentiated the growth-promoting effect of MCP-1, which was able to significantly induce cell proliferation even at a concentration as low as 0.1 pg/ml. These findings demonstrate that low concentrations of rat MCP-1 can directly promote rat VSMC proliferation and migration through the autocrine production of VEGF-A. monocyte chemotactic protein-1; endogenous vascular endothelial growth factor-A; remodeling; autocrine proliferation; chemokine

The real epidemiology and the possible consequences of anabolic-androgenic steroids (AAS) use still represent a very tricky task due to the difficulties in the quantification and detection of these drugs. Chronic use of AAS, frequently combined with other illicit substances, can induce tremendous negative effects on the reproductive system, but it is also associated with an increased overall and cardiovascular mortality risk. In the present review we summarize and discuss the available evidence regarding the negative impact of AAS on the male reproductive system, providing practical suggestions to manage these problems. For this purpose a meta-analysis evaluating the effects of AAS abusers vs. controls on several hormonal, reproductive and metabolic parameters was performed. In addition, in order to overcome possible limitations related to the combined use of different AAS preparations, we also retrospectively re-analyzed data on animal models treated with supraphysiological dosage of testosterone (T), performed in our laboratory. Available data clearly indicated that AAS negatively affect endogenous T production. In addition, increased T and estradiol circulating levels were also observed according to the type of preparations used. The latter leads to an impairment of sperm production and to the development of side effects such as acne, hair loss and gynecomastia. Furthermore, a worse metabolic profile, characterized by reduced high density lipoprotein and increased low density lipoprotein cholesterol levels along with an increased risk of hypertension has been also detected. Finally sexual dysfunctions, often observed upon doping, represent one the most probable unfavorable effects of AAS abuse. [ABSTRACT FROM AUTHOR]

Androgen deprivation therapy (ADT) is the gold standard treatment in patients with locally advanced or metastatic prostate cancer (PC). Emerging evidence has documented a tight association between ADT and body composition, along with metabolic profile impairment. These alterations might underpin the observed ADT-related increase in cardiovascular (CV) and thromboembolic (venous thromboembolism, VTE) mortality and morbidity. However, the specific mechanisms underlying these associations have not yet been completely elucidated. In the present review we summarize and discussed the available evidence linking ADT to increased cardio-metabolic risk, using both preclinical and clinical data. When possible, metaanalytic studies were preferred. Preclinical evidence, using a rabbit model of gonadotrophin-releasing hormone analogueinduced hypogonadism, indicates that the induced condition is associated with a dramatic increase in visceral adiposity and with an impairment of acetylcholine induced vascular relaxation, along with an increased propensity towards fatty liver. This suggests a direct role of ADT in inducing a worsened metabolic profile. In contrast, available clinical data are not sufficient to clarify a direct pathogeniclink between reduced testosterone (T) and altered metabolism. In fact, although T deprivation is associated with an altered metabolism, it is possible that the association between ADT and CV or VTE risk could simply be the result of a selection bias, related to the poor health status of patients with advanced PC. Despite the aforementioned considerations, all patients who are candidatesfor ADT should be screened for CV risk factors at baseline and monitored during the therapy. Life-style modifications and physical exercise are strongly encouraged. [ABSTRACT FROM AUTHOR]

In this study, we investigated steroidogenic gene mRNA expression in human vaginas and verified the ability of human vagina smooth muscle cells (hvSMCs) to synthesize androgens from upstream precursor dehydroepiandrosterone (DHEA). As a readout for androgen receptor (AR) activation, we evaluated the mRNA expression of various androgen-dependent markers. hvSMCs were isolated from vagina tissues of women undergoing surgery for benign gynecological diseases. In these cells, we evaluated mRNA expression of several steroidogenic enzymes and sex steroid receptors using real time reverse transcription-polymerase chain reaction. Androgen production was quantified with liquid chromatography tandem-mass spectrometry (LC-MS/MS). In vaginal tissues, AR mRNA was significantly less expressed than estrogen receptor α, whereas in hvSMCs, its mRNA expression was higher than progestin and both estrogen receptors. In hvSMCs and in vaginal tissue, when compared to ovaries, the mRNA expression of proandrogenic steroidogenic enzymes (HSD3β1/β2, HSD17β3/β5), along with 5α-reductase isoforms and sulfotransferase, resulted as being more abundant. In addition, enzymes involved in androgen inactivation were less expressed than in the ovaries. The LC-MS/MS analysis revealed that, in hvSMCs, short-term DHEA supplementation increased Δ4-androstenedione levels in spent medium, while increasing testosterone and DHT secretion after longer incubation. Finally, androgenic signaling activation was evaluated through AR-dependent marker mRNA expression, after DHEA and T stimulation. This study confirmed that the human vagina is an androgen-target organ with the ability to synthesize androgens, thus providing support for the use of androgens for local symptoms of genitourinary syndrome in menopause. [ABSTRACT FROM AUTHOR]

Background: Testosterone (T) plays a pivotal role in coordinating a series of psychological, cognitive and physical events that might (or might not) culminate in male sexual activity. In fact, T deficiency is associated, in a statistically significant way, with several sexual dysfunctions including erectile dysfunction (ED), reduction of spontaneous erection and hypoactive sexual desire (HSD). Although these associations are statistically significant, there is debate if they are also clinically meaningful. In addition, sexual dysfunctions are present also in several metabolic conditions ‐ such as type 2 diabetes mellitus and obesity ‐ that often associate with low T. In particular, this is the case of ED, but not of HSD, that, therefore, should be considered a more genuine correlate of T deficiency in adulthood and aging (late‐onset hypogonadism, LOH). Objectives: The aim of this review is to scrutinize evidence from our and other studies on sexual effects of T replacement therapy (TRT) in LOH. Materials and methods: We will use preclinical and clinical data coming from our and other laboratories and meta‐analyses. Results: Intervention studies in clinical trials involving subjects with LOH, and their meta‐analyses, indicate that TRT is able to ameliorate HSD, spontaneous erection and ED. However, the relative improvement of ED by TRT is marginal [2‐3 points of International Index of Erectile Function‐erectile function domain (IIEF‐EFD)] and significantly smoothed in subjects with the aforementioned metabolic conditions. In LOH, positive effects of TRT on other domains of sexual activity, such as orgasm and sexual satisfaction, are also apparent in the different meta‐analyses. Discussion and conclusions: Hence, TRT is a reasonable treatment for restoring sexual drive in LOH, with some additional positive effects also on erection (spontaneous and sexual‐related) and on orgasm. In contrast, preclinical and clinical studies indicate that T administration to eugonadal subjects does not improve male sexual activity. [ABSTRACT FROM AUTHOR]

Lifestyle modifications, including physical exercise (PhyEx), are well-known treatments for metabolic syndrome (MetS), a cluster of metabolic and cardi ovascular risk factors often associated to hypogonadism. Given the trophic role of tes tosterone on skeletal muscle (SkM), this study was aimed at evaluating the effects of testosterone treatment on SkM metabolism and exercise performance in male rabbits with high-fat diet (HFD)- induced MetS. HFD rabbits, treated or not with testosterone (30 mg/kg/week) for 12 weeks, were compared to regular diet animals (RD). A subset of each group was exercise-trained for 12 weeks. HFD increased type-II (fast, gly colytic) and decreased type-I (slow, oxidative) muscle fibers compared to RD as evaluat ed by RT-PCR and histochemistry. Testosterone reverted these effects, also inducing the expression of mitochondrial respiration enzymes and normalizing HFD-induced mitochondrial cristae reduction. Moreover, testosterone significantly increased the expression of myogenic/differentiation markers and genes related to glucidic/lipid meta bolism. At the end of the PhyEx protocol, when compared to RD, HFD rabbits showed a s ignificant reduction of running distance and running time, while testosterone counte racted this effect, also decreasing lactate production. In the trained groups, musc le histology showed a significant reduction of oxidative fibers in HFD compared to RD and the positive effect of testosterone in maintaining oxidative metabolism, as a lso demonstrated by analyzing mitochondrial ultrastructure, succinate dehydrogenase activity and ATP production. Our results indicate that testosterone could be useful to promote oxidative muscle metabolism altered by MetS, thus improving exercise performance. Conversely, testosterone administration to otherwise eugonadal rabbits (RD) only increased muscle fiber diameter but not endurance performance. [ABSTRACT FROM AUTHOR]