Microbiota alterations associated with vascular diseases: postbiotics as a next-generation magic bullet for gut-vascular axis.

The intestinal microbiota represents a key element in maintaining the homeostasis and health conditions of the host. Vascular pathologies and other risk factors such as aging have been recently associated with dysbiosis. The qualitative and quantitative alteration of the intestinal microbiota hinders correct metabolic homeostasis, causing structural and functional changes of the intestinal wall itself. Impairment of the intestinal microbiota, combined with the reduction of the barrier function, worsen the pathological scenarios of peripheral tissues over time, including the vascular one. Several experimental evidence, collected in this review, describes in detail the changes of the intestinal microbiota in dysbiosis associated with vascular alterations, such as atherosclerosis, hypertension, and endothelial dysfunction, the resulting metabolic disorders and how these can impact on vascular health. In this context, the gut-vascular axis is considered, for the first time, as a merged unit involved in the development and progression of vascular pathologies and as a promising target. Current approaches for the management of dysbiosis such as probiotics, prebiotics and dietary modifications act mainly on the intestinal district. Postbiotics, described as preparation of inanimate microorganisms and/or their components that confers health benefits on the host, represent an innovative strategy for a dual management of intestinal dysbiosis and vascular pathologies. In this context, this review has the further purpose of defining the positive effects of the supplementation of bacterial strains metabolites (short­chain fatty acids, exopolysaccharides, lipoteichoic acids, gallic acid, and protocatechuic acid) restoring intestinal homeostasis and acting directly on the vascular district through the gut-vascular axis.

Natural H2S-donors: A new pharmacological opportunity for the management of overweight and obesity.

The prevalence of overweight and obesity has progressively increased in the last few years, becoming a real threat to healthcare systems. To date, the clinical management of body weight gain is an unmet medical need, as there are few approved anti-obesity drugs and most require an extensive monitoring and vigilance due to risk of adverse effects and poor patient adherence/persistence. Growing evidence has shown that the gasotransmitter hydrogen sulfide (H2S) and, therefore, H2S-donors could have a central role in the prevention and treatment of overweight/obesity. The main natural sources of H2S-donors are plants from the Alliaceae (garlic and onion), Brassicaceae (e.g., broccoli, cabbage, and wasabi), and Moringaceae botanical families. In particular, polysulfides and isothiocyanates, which slowly release H2S, derive from the hydrolysis of alliin from Alliaceae and glucosinolates from Brassicaceae/Moringaceae, respectively. In this review, we describe the emerging role of endogenous H2S in regulating adipose tissue function and the potential efficacy of natural H2S-donors in animal models of overweight/obesity, with a final focus on the preliminary results from clinical trials. We conclude that organosulfur-containing plants and their extracts could be used before or in combination with conventional anti-obesity agents to improve treatment efficacy and reduce inflammation in obesogenic conditions. However, further high-quality studies are needed to firmly establish their clinical efficacy.

Erucin, a natural isothiocyanate, exerts pro-angiogenic properties in cultured endothelial cells and reverts angiogenic impairment induced by high glucose.

Insufficient vessel maintenance adversely impacts patients in terms of tissue reperfusion following stroke or myocardial infarction, as well as during wound healing. Angiogenesis impairment is a feature typical of metabolic disorders acting at the cardiovascular level, such as diabetes. Therapeutic angiogenesis regulation offers promising clinical implications, and natural compounds as pro-angiogenic nutraceuticals hold valuable applications in regenerative medicine. By using cultured endothelial cells from human umbilical veins (HUVEC) we studied functional and molecular responses following exposure to erucin, a natural isothiocyanate derived from Brassicaceae plants and extracted from the seeds of rocket. Erucin (at nanomolar concentrations) promotes cell migration and tube formation, similar to vascular endothelial growth factor (VEGF), through mobilizing paxillin at endothelial edges. At the molecular level, erucin induces signaling pathways typical of angiogenesis activation, namely Ras, PI3K/AKT, and ERK1/2, leading to VEGF expression and triggering its autocrine production, as pharmacological inhibition of soluble VEGF and VEGFR2 dampens endothelial functions. Furthermore, erucin, alone and together with VEGF, preserves endothelial angiogenic functions under pathological conditions, such as those induced in HUVEC by high glucose (HG) exposure. Erucin emerges as a compelling candidate for therapeutic revascularization applications, showcasing promising prospects for natural compounds in regenerative medicine, particularly in addressing angiogenesis-related disorders.

Influence of Polyphenols on Adipose Tissue: Sirtuins as Pivotal Players in the Browning Process.

Adipose tissue (AT) can be classified into two different types: (i) white adipose tissue (WAT), which represents the largest amount of total AT, and has the main function of storing fatty acids for energy needs and (ii) brown adipose tissue (BAT), rich in mitochondria and specialized in thermogenesis. Many exogenous stimuli, e.g., cold, exercise or pharmacological/nutraceutical tools, promote the phenotypic change of WAT to a beige phenotype (BeAT), with intermediate characteristics between BAT and WAT; this process is called "browning". The modulation of AT differentiation towards WAT or BAT, and the phenotypic switch to BeAT, seem to be crucial steps to limit weight gain. Polyphenols are emerging as compounds able to induce browning and thermogenesis processes, potentially via activation of sirtuins. SIRT1 (the most investigated sirtuin) activates a factor involved in mitochondrial biogenesis, peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), which, through peroxisome proliferator-activated receptor γ (PPAR-γ) modulation, induces typical genes of BAT and inhibits genes of WAT during the transdifferentiation process in white adipocytes. This review article aims to summarize the current evidence, from pre-clinical studies to clinical trials, on the ability of polyphenols to promote the browning process, with a specific focus on the potential role of sirtuins in the pharmacological/nutraceutical effects of natural compounds.

Anti-Proliferative Properties of the Novel Hybrid Drug Met-ITC, Composed of the Native Drug Metformin with the Addition of an Isothiocyanate H2S Donor Moiety, in Different Cancer Cell Lines.

Metformin (Met) is the first-line therapy in type 2 diabetes mellitus but, in last few years, it has also been evaluated as anti-cancer agent. Several pathways, such as AMPK or PI3K/Akt/mTOR, are likely to be involved in the anti-cancer Met activity. In addition, hydrogen sulfide (H2S) and H2S donors have been described as anti-cancer agents affecting cell-cycle and inducing apoptosis. Among H2S donors, isothiocyanates are endowed with a further anti-cancer mechanism: the inhibition of the histone deacetylase enzymes. On this basis, a hybrid molecule (Met-ITC) obtained through the addition of an isothiocyanate moiety to the Met molecule was designed and its ability to release Met has been demonstrated. Met-ITC exhibited more efficacy and potency than Met in inhibiting cancer cells (AsPC-1, MIA PaCa-2, MCF-7) viability and it was less effective on non-tumorigenic cells (MCF 10-A). The ability of Met-ITC to release H2S has been recorded both in cell-free and in cancer cells assays. Finally, its ability to affect the cell cycle and to induce both early and late apoptosis has been demonstrated on the most sensitive cell line (MCF-7). These results confirmed that Met-ITC is a new hybrid molecule endowed with potential anti-cancer properties derived both from Met and H2S.

Potential effects of Alliaceae and Brassicaceae edible plants on blood glucose levels in patients with type 2 diabetes: A systematic review and meta-analysis of clinical trials.

Type 2 diabetes (T2D) is one of the main leading causes of mortality worldwide, and its global prevalence will increase within the next years. Many pre-clinical studies demonstrated the potential effects of edible plants from Alliaceae and Brassicaceae on the regulation of blood glucose levels. Of note, secondary metabolites from Alliaceae and Brassicaceae share the ability to slowly release hydrogen sulfide (H2S), which is emerging as a crucial modulator of the "glucose-insulin system". However, the results of clinical studies evaluating the effects of such edible plants on glycaemic control in patients with T2D are quite conflicting. We performed a systematic review and meta-analysis of controlled clinical trials, both parallel and cross-over, searching four databases (Pubmed, Embase, Scopus and the Cochrane library). Only English-written papers evaluating the effects of Alliaceae and Brassicaceae on glycaemic parameters in diabetic patients have been included. 16 studies met the inclusion criteria, and 12 were included in the random-effects meta-analysis. Consumption of Alliaceae or Brassicaceae significantly reduced fasting blood glucose (FBG) levels compared with the placebo group (mean reduction: -12.67 mg/dl [95% confidence interval (CI) - 19.66; - 5.68]). Moreover, Alliaceae and Brassicaceae significantly improved the effects of standard antidiabetic therapy (mean reduction in FBG levels in patients receiving combination therapy compared with patients only receiving standard antidiabetic therapy: -6.75 mg/dl [-12.62; -0.88]). Overall, the regular consumption of these edible plants was safe and well-tolerated. We suggest that edible plants containing organosulfur compounds are endowed with promising nutraceutical potential in the treatment of T2D.

Cardiovascular benefits of Eruca sativa mill. Defatted seed meal extract: Potential role of hydrogen sulfide.

Eruca sativa Mill. is an edible plant belonging to the Brassicaceae botanical family with a long story as a medicinal material, mainly linked to the presence of glucoerucin. One of the main products of this glucosinolate is erucin, a biologicallly active isothiocyanate recently recognized as a hydrogen sulfide (H2 S) donor. In this work, an Eruca sativa extract has been obtained from a defatted seed meal (DSM), achieving a powder rich in thiofunctionalized glucosinolates, glucoerucin, and glucoraphanin, accounting for 95% and 5% of the total glucosinolate content (17% on a dry weight basis), associated with 13 identified phenolic acids and flavonoids accounting for 2.5%. In a cell-free model, Eruca sativa DSM extract slowly released H2 S. Moreover, this extract promoted significant hypotensive effects in hypertensive rats, and evoked dose-dependent cardioprotection in in vivo model of acute myocardial infarct, obtained through a reversible coronary occlusion. This latter effect was sensitive to blockers of mitochondrial KATP and Kv7.4 potassium channels, suggesting a potential role of these mitochondrial channels in the protective effects of Eruca sativa DSM extract. Accordingly, Eruca sativa DSM extract reduced calcium uptake and apoptotic cell death in isolated cardiac mitochondria. Taken together, these results demonstrate that Eruca sativa DSM extract is endowed with an interesting nutraceutical profile on the cardiovascular system due to, at least in part, its H2 S releasing properties. These results pave the way for future investigations on active metabolites.

Resveratrol-like Compounds as SIRT1 Activators.

The sirtuin 1 (SIRT1) activator resveratrol has emerged as a promising candidate for the prevention of vascular oxidative stress, which is a trigger for endothelial dysfunction. However, its clinical use is limited by low oral bioavailability. In this work, we have applied a previously developed computational protocol to identify the most promising derivatives from our in-house chemical library of resveratrol derivatives. The most promising compounds in terms of SIRT1 activation and oral bioavailability, predicted in silico, were evaluated for their ability to activate the isolated SIRT1 enzyme. Then, we assessed the antioxidant effects of the most effective derivative, compound 3d, in human umbilical vein endothelial cells (HUVECs) injured with H2O2 100 µM. The SIRT1 activator 3d significantly preserved cell viability and prevented an intracellular reactive oxygen species increase in HUVECs exposed to the oxidative stimulus. Such effects were partially reduced in the presence of a sirtuin inhibitor, sirtinol, confirming the potential role of sirtuins in the activity of resveratrol and its derivatives. Although 3d appeared less effective than resveratrol in activating the isolated enzyme, the effects exhibited by both compounds in HUVECs were almost superimposable, suggesting a higher ability of 3d to cross cell membranes and activate the intracellular target SIRT1.

Design, Synthesis and Evaluation of Novel Molecular Hybrids between Antiglaucoma Drugs and H2S Donors.

Glaucoma is a group of eye diseases consisting of optic nerve damage with corresponding loss of field vision and blindness. Hydrogen sulfide (H2S) is a gaseous neurotransmitter implicated in various pathophysiological processes. It is involved in the pathological mechanism of glaucomatous neuropathy and exerts promising effects in the treatment of this disease. In this work, we designed and synthetized new molecular hybrids between antiglaucoma drugs and H2S donors to combine the pharmacological effect of both moieties, providing a heightened therapy. Brinzolamide, betaxolol and brimonidine were linked to different H2S donors. The H2S-releasing properties of the new compounds were evaluated in a phosphate buffer solution by the amperometric approach, and evaluated in human primary corneal epithelial cells (HCEs) by spectrofluorometric measurements. Experimental data showed that compounds 1c, 1d and 3d were the hybrids with the best properties, characterized by a significant and long-lasting production of the gasotransmitter both in the aqueous solution (in the presence of L-cysteine) and in the intracellular environment. Because, to date, the donation of H2S by antiglaucoma H2S donor hybrids using non-immortalized corneal cells has never been reported, these results pave the way to further investigation of the potential efficacy of the newly synthesized compounds.

Anti-Inflammatory Effect of the Natural H2S-Donor Erucin in Vascular Endothelium.

Vascular inflammation (VI) represents a pathological condition that progressively affects the integrity and functionality of the vascular wall, thus leading to endothelial dysfunction and the onset of several cardiovascular diseases. Therefore, the research of novel compounds able to prevent VI represents a compelling need. In this study, we tested erucin, the natural isothiocyanate H2S-donor derived from Eruca sativa Mill. (Brassicaceae), in an in vivo mouse model of lipopolysaccharide (LPS)-induced peritonitis, where it significantly reduced the amount of emigrated CD11b positive neutrophils. We then evaluated the anti-inflammatory effects of erucin in LPS-challenged human umbilical vein endothelial cells (HUVECs). The pre-incubation of erucin, before LPS treatment (1, 6, 24 h), significantly preserved cell viability and prevented the increase of reactive oxygen species (ROS) and tumor necrosis factor alpha (TNF-α) levels. Moreover, erucin downregulated endothelial hyperpermeability and reduced the loss of vascular endothelial (VE)-Cadherin levels. In addition, erucin decreased vascular cell adhesion molecule 1 (VCAM-1), cyclooxygenase-2 (COX-2) and microsomal prostaglandin E-synthase 1 (mPGES-1) expression. Of note, erucin induced eNOS phosphorylation and counteracted LPS-mediated NF-κB nuclear translocation, an effect that was partially abolished in the presence of the eNOS inhibitor L-NAME. Therefore, erucin can control endothelial function through biochemical and genomic positive effects against VI.

Sirtuin 1-Activating Compounds: Discovery of a Class of Thiazole-Based Derivatives.

Sirtuin 1 (SIRT1) is a NAD+-dependent deacetylase implicated in various biological and pathological processes, including cancer, diabetes, and cardiovascular diseases. In recent years, SIRT1-activating compounds have been demonstrated to exert cardioprotective effects. Therefore, this enzyme has become a feasible target to treat cardiovascular diseases, and many SIRT1 activators, of a natural or synthetic origin, have been identified. In the present work, we developed thiazole-based SIRT1 activators, which showed remarkably higher SIRT1 activation potencies compared with those of the reference compound resveratrol when tested in enzymatic assays. Thiazole 8, a representative compound of this series, was also subjected to further pharmacological investigations, where it was proven to reduce myocardial damage induced by an in vivo occlusion/reperfusion event, thus confirming its cardioprotective properties. In addition, the cardioprotective effect of compound 8 was significantly higher than that of resveratrol. Molecular modeling studies suggest the binding mode of these derivatives within SIRT1 in the presence of the p53-AMC peptide. These promising results could pave the way to further expand and optimize this chemical class of new and potent SIRT1 activators as potential cardioprotective agents.

NLRP3 inflammasome in cardiovascular diseases: Pathophysiological and pharmacological implications.

Growing evidence points out the importance of nucleotide-binding oligomerization domain leucine-rich repeat and pyrin domain-containing protein 3 (NLRP3) inflammasome in the pathogenesis of cardiovascular diseases (CVDs), including hypertension, myocardial infarct (MI), ischemia, cardiomyopathies (CMs), heart failure (HF), and atherosclerosis. In this regard, intensive research efforts both in humans and in animal models of CVDs are being focused on the characterization of the pathophysiological role of NLRP3 inflammasome signaling in CVDs. In addition, clinical and preclinical evidence is coming to light that the pharmacological blockade of NLRP3 pathways with drugs, including novel chemical entities as well as drugs currently employed in the clinical practice, biologics and phytochemicals, could represent a suitable therapeutic approach for prevention and management of CVDs. On these bases, the present review article provides a comprehensive overview of clinical and preclinical studies about the role of NLRP3 inflammasome in the pathophysiology of CVDs, including hypertension, MI, ischemic injury, CMs, HF and atherosclerosis. In addition, particular attention has been focused on current evidence on the effects of drugs, biologics, and phytochemicals, targeting different steps of inflammasome signaling, in CVDs.

Synthesis and pharmacological characterization of mitochondrial KATP channel openers with enhanced mitochondriotropic effects.

Mitochondria play a key role for deciding fate of cells and thus are considered an attractive target for pharmacological interventions focused on containment of myocardial ischemia/reperfusion (I/R) injury. Notably, the activation of mitochondrial potassium (mitoK) channels produces a mild depolarization of mitochondrial membrane, that contributes to reduce the driving force to calcium uptake and prevents the formation of mitochondrial transition membrane pore (MPTP); these events underlie anti-ischemic cardioprotection. However, an ideal mitoK channel opener should possess the fundamental requirement to be delivered at mitochondrial level; therefore, to improve the mitochondrial delivery of a previously characterized spirocyclic benzopyrane F81, new compounds have been developed. The three original triphenylphosphonium (TPP+)-derivatives of F81 (1-3), were evaluated for their cardioprotective activity on both isolated cardiac mitochondria and cardiac H9c2 cell line. Compound 1 was further investigated in an in vivo infarct model. This work confirms that the TPP+ strategy applied to mitoKATP openers could foster mitochondrial delivery and enhance the cardioprotective effects of mitochondrial activators of potassium channels.

Advances in Technologies for Highly Active Omega-3 Fatty Acids from Krill Oil: Clinical Applications.

Euphausia superba, commonly known as krill, is a small marine crustacean from the Antarctic Ocean that plays an important role in the marine ecosystem, serving as feed for most fish. It is a known source of highly bioavailable omega-3 polyunsaturated fatty acids (eicosapentaenoic acid and docosahexaenoic acid). In preclinical studies, krill oil showed metabolic, anti-inflammatory, neuroprotective and chemo preventive effects, while in clinical trials it showed significant metabolic, vascular and ergogenic actions. Solvent extraction is the most conventional method to obtain krill oil. However, different solvents must be used to extract all lipids from krill because of the diversity of the polarities of the lipid compounds in the biomass. This review aims to provide an overview of the chemical composition, bioavailability and bioaccessibility of krill oil, as well as the mechanisms of action, classic and non-conventional extraction techniques, health benefits and current applications of this marine crustacean.

Eruca sativa Mill. seed extract promotes anti-obesity and hypoglycemic effects in mice fed with a high-fat diet.

Obesity is currently considered a major source of morbidity, with dramatic complications on health status and life expectancy. Several studies demonstrated the positive effects of Brassicaceae vegetables on obesity and related diseases, partially attributing these beneficial properties to glucosinolates and their derivatives isothiocyanates. Recently, isothiocyanates have been described as a hydrogen sulfide (H2 S)-releasing moiety, suggesting that H2 S may be at least in part responsible for the beneficial effects of Brassicaceae. In this work, the metabolic effects of an extract obtained from Eruca sativa Mill. seeds (E.S., Brassicaceae), containing high levels of glucoerucin, were evaluated in an experimental model of obesity. Male balb/c mice were fed for 10 weeks with standard (Std) diet or high fat (HF) diet supplemented with E.S. E.S. significantly contained the body weight gain in this obesity model, improving also glucose homeostasis. Interestingly, lower values of white adipose tissue mass and a significant reduction of adipocytes size were also observed. Moreover, E.S. enhanced the adipocytes metabolism, improving the citrate synthase activity and reduced triglyceride levels in mice fed with HF diet. Taken together, these results suggest that E.S. is endowed with an interesting translational and nutraceutical value in the prevention of metabolic disorders, suggesting that H2 S could be a key player.

Role of hydrogen sulfide in cardiovascular ageing.

Cardiovascular diseases are the main cause of morbidity and mortality in the Western society and ageing is a relevant non-modifiable risk factor. Morphological and functional alterations at endothelial level represent first events of ageing, inevitably followed by vascular dysfunction and consequent atherosclerosis that deeply influences cardiovascular health. Indeed, myocardial hypertrophy and fibrosis typically occur and contribute to compromise overall cardiac output. As regards the intracellular molecular mechanisms involved in the cardiovascular ageing, an intricate network is emerging, revealing a role for many mediators, including SIRT1/AMPK/PCG1α pathway, anti-oxidants factors (i.e. Nrf-2 and FOXOs) and pro-inflammatory cytokines. Thus, the search for pharmacological and non-pharmacological strategies that can promote a "healthy ageing", in order to slow down age-related machinery, are currently an exciting challenge for the biomedical research. Interestingly, hydrogen sulfide (H2S) has been recently recognized as a new player capable to influence intracellular machinery involved in ageing and then it is view as a potential target for preventing cardiovascular diseases. Therefore, this review is focused on the role of H2S in cardiovascular ageing, and on the evidence of the relationship between progressive decline in endogenous H2S levels and the onset of various cardiovascular age-related diseases.

Searching for novel hydrogen sulfide donors: The vascular effects of two thiourea derivatives.

The gasotransmitter hydrogen sulfide (H2S) is involved in the regulation of the vascular tone and an impairment of its endogenous production may play a role in hypertension. Thus, the administration of exogenous H2S may be a possible novel and effective strategy to control blood pressure. Some natural and synthetic sulfur compounds are suitable H2S-donors, exhibiting long-lasting H2S release; however, novel H2S-releasing agents are needed to improve the pharmacological armamentarium for the treatment of cardiovascular diseases. For this purpose, N-phenylthiourea (PTU) and N,N'-diphenylthiourea (DPTU) compounds have been investigated as potential H2S-donors. The thioureas showed long-lasting H2S donation in cell free environment and in human aortic smooth muscle cells (HASMCs). In HASMCs, DPTU caused membrane hyperpolarization, mediated by activation of KATP and Kv7 potassium channels. The thiourea derivatives promoted vasodilation in rat aortic rings, which was abolished by KATP and Kv7 blockers. The vasorelaxing effects were also observed in angiotensin II-constricted coronary vessels. In conclusion, thiourea represents an original H2S-donor functional group, which releases H2S with slow and long lasting kinetic, and promotes typical H2S-mediated vascular effects. Such a moiety will be extremely useful for developing original cardiovascular drugs and new chemical tools for investigating the pharmacological roles of H2S.

5α-dihydrotestosterone abrogates sex bias in asthma like features in the mouse.

Androgen levels inversely correlate with the incidence, susceptibility and severity of asthma. However, whether male sex hormones such as 5α-dihydrotestosterone (DHT) have beneficial effects on asthma symptoms and/or could affect asthma susceptibility have not been investigated. DHT administration to female mice, during the sensitization phase, abrogates the sex bias in bronchial hyperreactivity. This effect correlates with inhibition of leukotriene biosynthesis in the lung. DHT significantly inhibits also other asthma-like features such as airway hyperplasia and mucus production in sensitized female mice. Conversely, DHT does not affect plasma IgE levels as well as CD3+CD4+ IL-4+ cell and IgE+c-Kit+ cell infiltration within the lung but prevents pulmonary mast cell activation. The in vitro study on RBL-2H3 cells confirms that DHT inhibits mast cell degranulation. In conclusion, our data demonstrate that immunomodulatory effects of DHT on mast cell activation prevent the translation of allergen sensitization into clinical manifestation of asthma.

Tumor Suppressor Role of hsa-miR-193a-3p and -5p in Cutaneous Melanoma.

BACKGROUND: Remarkable deregulation of several microRNAs (miRNAs) is demonstrated in cutaneous melanoma. hsa-miR-193a-3p is reported to be under-expressed in tissues and in plasma of melanoma patients, but the role of both miR-193a arms in melanoma is not known yet. METHODS: After observing the reduced levels of miR-193a arms in plasma exosomes of melanoma patients, the effects of hsa-miR-193a-3p and -5p transfection in cutaneous melanoma cell lines are investigated. RESULTS: In melanoma cell lines A375, 501Mel, and MeWo, the ectopic over-expression of miR-193a arms significantly reduced cell viability as well as the expression of genes involved in proliferation (ERBB2, KRAS, PIK3R3, and MTOR) and apoptosis (MCL1 and NUSAP1). These functional features were accompanied by a significant downregulation of Akt and Erk pathways and a strong increase in the apoptotic process. Since in silico databases revealed TROY, an orphan member of the tumor necrosis receptor family, as a potential direct target of miR-193a-5p, this possibility was investigated using the luciferase assay and excluded by our results. CONCLUSIONS: Our results underline a relevant role of miR-193a, both -3p and -5p, as tumor suppressors clarifying the intracellular mechanisms involved and suggesting that their ectopic over-expression could represent a novel treatment for cutaneous melanoma patients.

Prodromal Intestinal Events in Alzheimer's Disease (AD): Colonic Dysmotility and Inflammation Are Associated with Enteric AD-Related Protein Deposition.

Increasing evidence suggests that intestinal dysfunctions may represent early events in Alzheimer's disease and contribute to brain pathology. This study examined the relationship between onset of cognitive impairment and colonic dysfunctions in a spontaneous AD model before the full development of brain pathology. SAMP8 mice underwent Morris water maze and assessment of faecal output at four, six and eight months of age. In vitro colonic motility was examined. Faecal and colonic Aß, tau proteins, α-synuclein and IL-1ß were assessed by ELISA. Colonic citrate synthase activity was assessed by spectrophotometry. Colonic NLRP3, caspase-1 and ASC expression were evaluated by Western blotting. Colonic eosinophil density and claudin-1 expression were evaluated by immunohistochemistry. The effect of Aß on NLRP3 signalling and mitochondrial function was tested in cultured cells. Cognitive impairment and decreased faecal output occurred in SAMP8 mice from six months. When compared with SAMR1, SAMP8 animals displayed: (1) impaired in vitro colonic contractions; (2) increased enteric AD-related proteins, IL-1ß, active-caspase-1 expression and eosinophil density; and (3) decreased citrate synthase activity and claudin-1 expression. In THP-1 cells, Aß promoted IL-1ß release, which was abrogated upon incubation with caspase-1 inhibitor or in ASC-/- cells. Aß decreased mitochondrial function in THP-1 cells. In SAMP8, enteric AD-related proteins deposition, inflammation and impaired colonic excitatory neurotransmission, occurring before the full brain pathology development, could contribute to bowel dysmotility and represent prodromal events in AD.