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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]

Metabolic syndrome (MetS) clusters cardiovascular and metabolic risk factors along with hypogonadism and erectile dysfunction. Lifestyle modifications including physical exercise (PhyEx) are well-known treatments for this condition. In this study, we analyzed the effect of PhyEx on hypothalamic-pituitary-testis axis and erectile function by use of an animal MetS model, previously established in rabbits fed a high-fat diet (HFD). Rabbits fed a regular diet (RD) were used as controls. A subset of both groups was trained on a treadmill. HFD rabbits showed typical MetS features, including HG (reduced T and LH) and impairment of erectile function. PhyEx in HFD rabbits completely restored plasma T and LH and the penile alterations. At testicular and hypothalamic levels, an HFD-induced inflammatory status was accompanied by reduced T synthesis and gonadotropin-releasing hormone (GnRH) immunopositivity, respectively. In the testis, PhyEx normalized HFD-related macrophage infiltration and increased the expression of steroidogenic enzymes and T synthesis. In the hypothalamus, PhyEx normalized HFD-induced gene expression changes related to inflammation and glucose metabolism, restored GnRH expression, particularly doubling mRNA levels, and regulated expression of molecules related to GnRH release (kisspeptin, dynorphin). Concerning MetS components, PhyEx significantly reduced circulating cholesterol and visceral fat. In multivariate analyses, cholesterol levels resulted as the main factor associated with MetS-related alterations in penile, testicular, and hypothalamic districts. In conclusion, our results show that PhyEx may rescue erectile function, exert anti-inflammatory effects on hypothalamus and testis, and increase LH levels and T production, thus supporting a primary role for lifestyle modification to combat MetS-associated hypogonadism and erectile dysfunction. [ABSTRACT FROM AUTHOR]

Farnesoid X receptor (FXR) activation by obeticholic acid (OCA) has been demonstrated to inhibit inflammation and fibrosis development in liver, kidney and intestine in multiple disease models. FXR activation has also been demonstrated to suppress the inflammatory response and to promote lung repair after lung injury. This study investigated the protective effects of OCA treatment (3 or 10 mg/kg/day) on inflammation, tissue remodeling and fibrosis in the bleomycin-induced pulmonary fibrosis rat model. Effects of OCA treatment on morphological and molecular alterations of the lung, as well as remodeling of the alveoli and the right ventricle were also evaluated. Lung function was assessed by measuring airway resistance to inflation. In the acute phase (7 days), bleomycin promoted an initial thickening and fibrosis of the lung interstitium, with upregulation of genes related to epithelial proliferation, tissue remodeling and hypoxia. At 28 days, an evident increase in the deposition of collagen in the lungs was observed. This excessive deposition was accompanied by an upregulation of transcripts related to the extracellular matrix (TGFβ1, SNAI1 and SNAI2), indicating lung fibrosis. Administration of OCA protected against bleomycin-induced lung damage by suppressing molecular mechanisms related to epithelial-to-mesenchymal transition (EMT), inflammation and collagen deposition, with a dose-dependent reduction of proinflammatory cytokines such as IL-1β and IL-6, as well as TGF-β1 and SNAI1 expression. Pirfenidone, a recently approved treatment for idiopathic pulmonary fibrosis (IPF), significantly counteracted bleomycin-induced pro-fibrotic genes expression, but did not exert significant effects on IL-1β and IL-6. OCA treatment in bleomycin-challenged rats also improved pulmonary function, by effectively normalizing airway resistance to inflation and lung stiffness in vivo. Results with OCA were similar, or even superior, to those obtained with pirfenidone. In conclusion, our results suggest an important protective effect of OCA against bleomycin-induced lung fibrosis by blunting critical mediators in the pathogenesis of IPF. [ABSTRACT FROM AUTHOR]

Metabolic syndrome (MetS) and benign prostatic hyperplasia (BPH)/lower urinary tract symptoms (LUTS) are often associated. One of their common denominators is hypogonadism. However, testosterone supplementation is limited by concerns for potential prostatic side effects. The objective was to determine whether MetS-associated prostate alterations are prevented by testosterone supplementation. We used a previously described animal model of MetS, obtained by feeding male rabbits a high-fat diet (HFD) for 12 weeks. Subsets of HFD rabbits were treated with testosterone or with the farnesoid X receptor agonist INT-747. Rabbits fed a standard diet were used as controls. HFD-animals develop hypogonadism and all the MetS features: hyperglycemia, glucose intolerance, dyslipidemia, hypertension, and visceral obesity. In addition, HFD-animals show a prostate inflammation. Immunohistochemical analysis demonstrated that HFD-induced prostate fibrosis, hypoxia, and inflammation. The mRNA expression of several proinflammatory (IL8, IL6, IL1b, and TNFa), T lymphocyte (CD4, CD8, Tbet, Gata3, and ROR gt), macrophage (TLR2, TLR4, and STAMP2), neutrophil (lactoferrin), inflammation (COX2 and RAGE), and fibrosis/myofibroblast activation (TGFb, SM22a, aSMA, RhoA, and ROCK1/ROCK2) markers was significantly increased in HFD prostate. Testosterone, as well as INT-747, treatment prevented some MetS features, although only testosterone normalized all the HFD-induced prostate alterations. Interestingly, the ratio between testosterone and estradiol plasma level retains a significant, negative, association with all the fibrosis and the majority of inflammatory markers analyzed. These data highlight that testosterone protects rabbit prostate from MetS-induced prostatic hypoxia, fibrosis, and inflammation, which can play a role toward the development/progression of BPH/LUTS. [ABSTRACT FROM AUTHOR]

Metabolic syndrome (MetS) is known to be associated to inflammation and alteration in the hypothalamus, a brain region implicated in the control of several physiological functions, including energy homeostasis and reproduction. Previous studies demonstrated the beneficial effects of testosterone treatment (TTh) in counteracting some MetS symptoms in both animal models and clinical studies. This study investigated the effect of TTh (30 mg/kg/week for 12 weeks) on the hypothalamus in a high-fat diet (HFD)-induced animal model of MetS, utilizing quantitative RT-PCR and immunohistochemical analyses. The animal model recapitulates the human MetS features, including low testosterone/gonadotropin plasma levels. TTh significantly improved MetS-induced hypertension, visceral adipose tissue accumulation, and glucose homeostasis derangements. Within hypothalamus, TTh significantly counteracted HFD-induced inflammation, as detected in terms of expression of inflammatory markers and microglial activation. Moreover, TTh remarkably reverted the HFD-associated alterations in the expression of important regulators of energy status and reproduction, such as the melanocortin and the GnRH-controlling network. Our results suggest that TTh may exert neuroprotective effects on the HFD-related hypothalamic alterations, with positive outcomes on the circuits implicated in the control of energy metabolism and reproductive tasks, thus supporting a possible role of TTh in the clinical management of MetS. [ABSTRACT FROM AUTHOR]

Metabolic Syndrome (MetS) is a cluster of clinical conditions, associated to an increased cardiovascular (CV) and metabolic risk along with hypogonadism (HG). Lifestyle modifications (including physical exercise, PhyEx) are well-known treatments for this condition [1]. We previously established a rabbit model of MetS that recapitulates the human phenotype, including HG [2]. We now report studies on the effects of PhyEx on hypothalamus-pituitary-testis (HPT) axis. MetS was induced in adult male rabbits fed a high-fat diet (HFD). Rabbits fed a regular diet were used as controls (RD). RD and HFD rabbits were exercise-trained to run on a treadmill for 12 weeks (RD + PhyEx and HFD+ PhyEx). HFD rabbits showed typical metabolic and CV features of MetS along with hypogonadotropic HG (reduced testosterone and LH plasma levels). Within the hypothalamus (preoptic region) a significant reduction of GnRH- and KISS1R-positive neurons, along with the increase of genes related to inflammation (COX2, IL6, CD68), glucose metabolism (GLUT1, GLUT4, IRS-1) and estrogen action (ERb, GPR30) was detected in HFD rabbit, as compared to RD group. Immunohistochemistry analysis confirmed the HFD-induced hypothalamic inflammation. Interestingly, genes encoding for inhibitory factors for GnRH, such as NPY, were also increased in HFD hypothalamus. Within the testis, HFD down-regulated LH receptor and all the steroidogenic enzymes leading to T synthesis. PhyEx completely restored T and LH plasma levels and GnRH/KISS1R immunostaining. All the aforementioned HDF-induced increase of inflammatory markers were significantly reduced in HFD+ PhyEx, with the exception of IL6. Moreover, at hypothalamic level, PhyEx decreased orexigenic and GnRH-inhibiting factors (dinorphin and its receptors OPRD1 and OPRK1), whereas increased anorexigenic ones (POMC). Within the testis, genes related to T formation (17ßHSD3) and metabolism (5a-reductase 1) were increased by PhyEx. In conclusion, in this experimental model, endurance training (PhyEx) completely reverted MetS-induced hypogonadotropic hypogonadism, exerting beneficial effects on the HPT axis. Particularly, in the hypothalamus PhysEX reduced HFD-induced inflammation. Hence, aerobic exercise training can be regarded an interesting strategy to combat MetS-associated alterations of the HPT axis. [ABSTRACT FROM AUTHOR]

Chronic inflammation is involved in the genitourinary syndrome of menopause (GSM) and beneficial effects of androgens in the vagina have been descr ibed. We investigated the potential involvement of human vagina smooth muscle cells (hvSMCs) in the inflammatory response and the immunomodulatory effect of androgen receptor (AR) agonist dihydrotestosterone (DHT). HvSMCs isolated from menopausal women were evaluated for sex steroids receptors and toll-like receptors mRNA expression, and left untreated or treated in vitro with lipopolysaccharide (LPS) or IFNγ, in the presence or absence of DHT. We evaluated mRNA expression (by RT-PCR) and se cretion in cell culture supernatants (by a bead-based immunoassay) of pro-inflammatory markers. Nuclear translocation of NF-κB (by immunofluorescence) and cell surface HLA-DR expression (by flow cytometry) were also evaluated. Similar experiments were repeated in rat vSMCs (rvSMCs). In hvSMCs and rvSMCs, AR was highly expressed. DHT pr e-treatment inhibited LPS-induced mRNA expression of several pro-inflammatory mediators (i.e. COX2, IL-6, IL-12A and IFNγ), effect significantly blunted by AR antagonist bicalutamide. DHT significantly counteracted the secretion of IL-1RA, IL-2, IL-5, IL-15, FGF, VEGF and TNFa. LPS-induced NF-κB nuclear translocation was significantly inhibited by DHT, an effect counteracted by bicalutamide. DHT pre-treatment significantly decreased IFNγ-induced expression of HLA-DR, mRNA expression of iNOS, COX2 and MCP1, and secretion of IL-1, IL-2, IL-5, IL-6, MCP1 and GCSF. Similar effects were observed in rvSMCs. The activation of AR suppresses the inflammatory response in hvSMCs, reducing their potential to be involved in the initiation and maintaining of inflammation, thus representing a therapeutic strategy in conditions, such as the GSM. [ABSTRACT FROM AUTHOR]

Farnesoid X receptor (FXR) activation by obeticholic acid (OCA) has been demonstrated to inhibit inflammation and fibrosis development and even induce fibrosis regression in liver, kidney and intestine in multiple disease models. OCA also inhibits liver fibrosis in nonalcoholic steatohepatitis patients. FXR activation has also been demonstrated to suppress the inflammatory response and to promote lung repair after lung injury. This study investigated the effects of OCA treatment (3, 10 or 30 mg/kg, daily for 5 days a week, for 7 and/or 28 days) on inflammation, tissue remodeling and fibrosis in the monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH) rat model. Treatment with OCA attenuated MCT-induced increased pulmonary arterial wall thickness and right ventricular hypertrophy, by i) blunting pathogenic inflammatory mechanisms (downregulation of interleukin 6, IL-6, and monocyte chemoattractant protein-1, MCP-1) and ii) enhancing protective mechanisms counteracting fibrosis and endothelial/mesenchymal transition. MCT-injected rats also showed a marked decrease of pulmonary artery responsiveness to both endothelium-dependent and independent relaxant stimuli, such as acetylcholine and a nitric oxide donor, sodium nitroprusside. Administration of OCA (30 mg/kg) normalized this decreased responsiveness. Accordingly, OCA treatment induced profound beneficial effects on lung histology. In particular, both OCA doses markedly reduced the MCT-induced medial wall thickness increase in small pulmonary arteries. To evaluate the objective functional improvement by OCA treatment of MCT-induced PAH, we performed a treadmill test and measured duration of exercise. MCT significantly reduced, and OCA normalized treadmill endurance. Results with OCA were similar, or even superior, to those obtained with tadalafil, a well-established treatment of PAH. In conclusion, OCA treatment demonstrates cardiopulmonary protective effects, modulating lung vascular remodeling, reducing right ventricular hypertrophy and significantly improving exercise capacity. Thus, OCA can restore the balance between relaxant and contractile pathways in the lung, promoting cardiopulmonary protective actions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Feeding rabbits with HFD induces MetS and hypogonadotropic hypogonadism (HH). [•] MetS-related HH is associated with hypothalamic inflammation and reduced KISS1R. [•] Overexpression of IL-6 and GLUT4 negatively correlated to gonadotropin deficiency. [•] Correcting glucose intolerance improves hypothalamic inflammation and GnRH expression. [ABSTRACT FROM AUTHOR]