Beneficial Effect of H2S-Releasing Molecules in an In Vitro Model of Sarcopenia: Relevance of Glucoraphanin.

Sarcopenia is a gradual and generalized skeletal muscle (SKM) syndrome, characterized by the impairment of muscle components and functionality. Hydrogen sulfide (H2S), endogenously formed within the body from the activity of cystathionine-γ-lyase (CSE), cystathionine- ß-synthase (CBS), and mercaptopyruvate sulfurtransferase, is involved in SKM function. Here, in an in vitro model of sarcopenia based on damage induced by dexamethasone (DEX, 1 µM, 48 h treatment) in C2C12-derived myotubes, we investigated the protective potential of exogenous and endogenous sources of H2S, i.e., glucoraphanin (30 µM), L-cysteine (150 µM), and 3-mercaptopyruvate (150 µM). DEX impaired the H2S signalling in terms of a reduction in CBS and CSE expression and H2S biosynthesis. Glucoraphanin and 3-mercaptopyruvate but not L-cysteine prevented the apoptotic process induced by DEX. In parallel, the H2S-releasing molecules reduced the oxidative unbalance evoked by DEX, reducing catalase activity, O2- levels, and protein carbonylation. Glucoraphanin, 3-mercaptopyruvate, and L-cysteine avoided the changes in myotubes morphology and morphometrics after DEX treatment. In conclusion, in an in vitro model of sarcopenia, an impairment in CBS/CSE/H2S signalling occurs, whereas glucoraphanin, a natural H2S-releasing molecule, appears more effective for preventing the SKM damage. Therefore, glucoraphanin supplementation could be an innovative therapeutic approach in the management of sarcopenia.

Intra-tracheal administration increases gallium availability in lung: implications for antibacterial chemotherapy.

The emergence of pan-resistant strains in nosocomial settings underscores the urgent need of novel therapies targeting vital bacterial functions. Bacterial iron metabolism is a fascinating target for new antimicrobials. Iron mimetic metal Ga(III) has been repurposed as an antimicrobial drug, in pre-clinical studies and recent clinical studies have raised the possibility of using Ga(III) for the treatment of P. aeruginosa pulmonary infection. Ga(III) has been approved by FDA for the treatment of cancer, autoimmune and bone resorption disorders. However, some critical issues affect the therapeutic schedule of Ga(III), principally the intra-venous (i.v.) administration, and the nephrotoxicity caused by prolonged administration. Ga(III) aerosolization could represent a viable alternative for treatment of lung infections, since delivery of antimicrobial agents to the airways maximizes drug concentration at the site of infection, improves the therapeutic efficacy, and alleviates systemic toxic effects. We demonstrate the advantage of inhaled vs i.v. administered Ga(III), in terms of bio-distribution and lung acute toxicity, by using a rat model. In vivo results support the use of Ga(III) for inhalation since intra-tracheal Ga(III) delivery improved its persistence in the lung, while the i.v. administration caused rapid clearance and did not allow to attain a significant Ga(III) concentration in this organ. Moreover, local and systemic acute toxicity following intra-tracheal administration was not observed, since no significant signs of inflammation were found. At this stage of evidence, the direct administration of Ga(III) to the lung appears feasible and safe, boosting the development of Ga(III)-based drugs for inhalation therapy.

The Role of Perivascular Adipose Tissue-Derived Hydrogen Sulfide in the Control of Vascular Homeostasis.

Significance: Emerging evidence suggests that perivascular adipose tissue (PVAT) has a relevant role in the control of vascular tone in physiology and pathology. Healthy PVAT has anticontractile, anti-inflammatory, and antioxidative actions. Accumulating data from both human and experimental animal models indicate that PVAT dysfunction is conceivably coupled to cardiovascular diseases, and it is associated with vascular inflammation, oxidative stress, and arterial remodeling. Therefore, "healthy" PVAT may constitute a novel therapeutic target for the prevention and treatment of cardiovascular diseases. Recent Advances: Hydrogen sulfide (H2S) has been recognized as a vascular anti-contractile factor released from PVAT. The enzymes deputed to H2S biosynthesis are variously expressed in PVAT and strictly dependent on the vascular bed and species. Metabolic and cardiovascular diseases can alter the morphological and secretory characteristics of PVAT, influencing also the H2S signaling. Here, we discuss the role of PVAT-derived H2S in healthy conditions and its relevance in alterations occurring in vascular disorders. Critical Issues: We discuss how a better understanding may help in the prevention of vascular dysfunction related to alteration in PVAT-released H2S as well as the importance of the interplay between PVAT and H2S. Future Directions: We propose future directions to evaluate the contribution of each enzyme involved in H2S biosynthesis and their alteration/switch occurring in vascular disorders and the remaining challenges in investigating the role of H2S. Antioxid. Redox Signal. 37, 84-97.

A new original nutraceutical formulation ameliorates the effect of Tadalafil on clinical score and cGMP accumulation.

OBJECTIVE: To assess the efficacy of the combination of Tadalafil 5 mg and nutritional supplements composed by Panax ginseng, Moringa Oleifera and Rutin on erectile function in men with mild and moderate vasculogenic ED. METHODS: we prospectively enrolled 86 patients divided into two groups A (45), B (33) in this multicenter randomized, doubleblind, placebo-controlled trial . Drop out was 8 patients (3 patients in group A and 5 in Group B). At screening visit patients underwent clinical examination, blood test (hormonal and metabolic profile) and filled out the IIEF-5 questionnaire and the SEP-2, SEP-3. Patients were randomized by a computergenerated list to receive either Tadalafil 5 mg once daily plus nutritional supplement once daily (group A) or Tadalafil 5 mg plus placebo with the same administration schedule (group B) for 3 months. Blood samples, IIEF-5, SEP-2 and SEP-3 have been collected again after 3 months. cGMP was measured in platelets of 38 patients at baseline and after one months. RESULTS: Mean age was 59.98 ± 6.90 (range 38-69), mean IIEF-5 score at baseline was 13.59 ± 3.90. After three months of treatment, IIEF-5 score significantly improved in both groups compared to baseline (13.18 ± 3.75 vs 20.48 ± 2.24, p < 0.0001; 14.15 ± 4.09 vs 19.06 ± 4.36, p < 0.0001, in group A and group B respectively). Patients treated with Tadalafil plus nutritional supplement showed a significantly higher increase in IIEF-5 score compared to those who received placebo (7.27 ± 2.20 and 4.9 ± 2.79, respectively; p < 0.0001;). No hormonal differences and metabolic effects were found. According cGMP result, nutritional supplements ameliorates and extends the activity of the chronic treatment. CONCLUSIONS: IIEF-5 significant increase in group B, can be ascribed to the nutritional supplement properties and antioxidant effects of moringa oleifera, ginseng and rutin and this can enhance the endothelial NO and cGMP production.

Involvement of 3',5'-cyclic inosine monophosphate in cystathionine γ-lyase-dependent regulation of the vascular tone.

BACKGROUND AND PURPOSE: l-cysteine or hydrogen sulfide (H2 S) donors induce a biphasic effect on precontracted isolated vessels. The contractile effect occurs within a concentration range of 10 nM to 3 µM followed by vasodilatation at 30-100 µM. Here, we have investigated the signalling involved in the H2 S-induced contraction. EXPERIMENTAL APPROACH: Vascular response to NaHS or l-cysteine is evaluated on isolated precontracted with phenylephrine vessel rings harvested from wild type, cystathionine γ-lyase (CSE-/- ), soluble guanylyl cyclase (sGCα1-/- ) and endothelial nitric oxide synthase (eNOS-/- ) knock-out mice. The cAMP, cGMP and inosine 3',5'-cyclic monophosphate (cIMP) levels are simultaneously quantified using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis. The involvement of sGC, phosphodiesterase (PDE) 4A and PDE5 are also evaluated. KEY RESULTS: CSE-derived H2 S-induced contraction requires an intact eNOS/NO/sGC pathway and involves cIMP as a second messenger. H2 S contractile effect involves a transient increase of cGMP and cAMP metabolism caused by PDE5 and PDE4A, thus unmasking cIMP contracting action. The stable cell-permeable analogue of cIMP elicits concentration-dependent contraction on a stable background tone induced by phenylephrine. The lack of cIMP, coupled to the hypocontractility displayed by vessels harvested from CSE-/- mice, confirms that H2 S-induced contraction involves cIMP. CONCLUSION AND IMPLICATIONS: The endothelium dynamically regulates vessel homeostasis by modulating contractile tone. This also involves CSE-derived H2 S that is mediated by cIMP.

Uterine Dysfunction in Diabetic Mice: The Role of Hydrogen Sulfide.

It is well-known that the physiological uterine peristalsis, related to several phases of reproductive functions, plays a pivotal role in fertility and female reproductive health. Here, we have addressed the role of hydrogen sulfide (H2S) signaling in changes of uterine contractions driven by diabetes in non-obese diabetic (NOD) mice, a murine model of type-1 diabetes mellitus. The isolated uterus of NOD mice showed a significant reduction in spontaneous motility coupled to a generalized hypo-contractility to uterotonic agents. The levels of cyclic nucleotides, cAMP and cGMP, notoriously involved in the regulation of uterus homeostasis, were significantly elevated in NOD mouse uteri. This increase was well-correlated with the higher levels of H2S, a non-specific endogenous inhibitor of phosphodiesterases. The exposure of isolated uterus to L-cysteine (L-Cys), but not to sodium hydrogen sulfide, the exogenous source of H2S, showed a weak tocolytic effect in the uterus of NOD mice. Western blot analysis revealed a reorganization of the enzymatic expression with an upregulation of 3-mercaptopyruvate-sulfurtransferase (3-MST) coupled to a reduction in both cystathionine-ß-synthase (CBS) and cystathionine-γ-lyase (CSE) expression. In conclusion, the increased levels of cyclic nucleotides dysregulate the uterus peristalsis and contractility in diabetic mice through an increase in basal H2S synthesis suggesting a role of 3-MST.