Hydrogen sulfide dysfunction in metabolic syndrome-associated vascular complications involves cGMP regulation through soluble guanylyl cyclase persulfidation

Here, by using in vitro and ex vivo approaches, we elucidate the impairment of the hydrogen sulfide (H2S) pathway in vascular complications associated with metabolic syndrome (MetS). In the in vitro model simulating hyperlipidemic/hyperglycemic conditions, we observe significant hallmarks of endothelial dysfunction, including eNOS/NO signaling impairment, ROS overproduction, and a reduction in CSE-derived H2S. Transitioning to an ex vivo model using db/db mice, a genetic MetS model, we identify a downregulation of CBS and CSE expression in aorta, coupled with a diminished L-cysteine-induced vasorelaxation. Molecular mechanisms of eNOS/NO signaling impairment, dissected using pharmacological and molecular approaches, indicate an altered eNOS/Cav-1 ratio, along with reduced Ach- and Iso-induced vasorelaxation and increased L-NIO-induced contraction. In vivo treatment with the H2S donor Erucin ameliorates vascular dysfunction observed in db/db mice without impacting eNOS, further highlighting a specific action on smooth muscle component rather than the endothelium. Analyzing the NO signaling pathway in db/db mice aortas, reduced cGMP levels were detected, implicating a defective sGC/cGMP signaling. In vivo Erucin administration restores cGMP content. This beneficial effect involves an increased sGC activity, due to enzyme persulfidation observed in sGC overexpressed cells, coupled with PDE5 inhibition. In conclusion, our study demonstrates a pivotal role of reduced cGMP levels in impaired vasorelaxation in a murine model of MetS involving an impairment of both H2S and NO signaling. Exogenous H2S supplementation through Erucin represents a promising alternative in MetS therapy, targeting smooth muscle cells and supporting the importance of lifestyle and nutrition in managing MetS.

Characterization of functional regions in the Schizosaccharomyces pombe mei3 developmental activator

The Schizosaccharomyces pombe mei3(+) gene is expressed only in diploid cells undergoing meiosis. Ectopic expression of mei3(+) in haploid cells causes meiotic catastrophe. Mei3 is an inhibitor of Ran1/Pat1 kinase and contains a nine-amino-acid motif, Mei3-RKDIII, that resembles two regions in the Ste11 substrate for Ran1/Pat1. Substitution of serine for Arg-81 within Mei3-RKDIII transforms the inhibitor into a substrate for Ran1/Pat1. Thus, it is likely that Mei3-RKDIII defines a pseudosubstrate sequence. In this study, we constructed a series of mei3 deletion mutations and assayed each for activity. This analysis indicates that the carboxy-terminal domain of Mei3 is sufficient for function in vivo. Alanine-scanning mutagenesis identifies critical residues within the inhibitory domain. Two mutations, SM1 and SM8, fail to cause meiotic catastrophe. The SM1 mutation contains alterations of amino acid residues in Mei3-RKDIII. Recombinant SM1 protein exhibits reduced ability to inhibit Ran1/Pat1 kinase in vitro and interacts inefficiently with the kinase in a two-hybrid assay. The SM8 protein binds to Ran1/Pat1 in a two-hybrid assay but fails to inhibit Ran1/Pat1 substrate phosphorylation in vitro. These findings provide evidence that Mei3-RKDIII defines a Ran1/Pat1-binding site that is necessary but not sufficient for inhibition of the kinase. Using fusions to green fluorescent protein, the cellular localization of Ran1 and Mei3 was examined in living cells. Ran1 is concentrated in the nucleus. Mei3 is also enriched in the nucleus and, consistent with the genetic and biochemical results, the inhibitory domain of Mei3 is sufficient for nuclear localization.

[Contribution of a combination of alpha and beta benzopyrones, flavonoids and natural terpenes in the treatment of lymphedema of the lower limbs at the 2d stage of the surgical classification]

HYPOTHESIS

To create a phlebolymphologic therapy in order: to activate venous system; to activate lymphatic system; to activate macrophagic system; to reduce the proteic lymphatic load.

EXPERIMENTAL

A study was performed on the use of an ideal phlebolymphological association (Tonka Beans, Gingko Biloba, Melilotus Officinalis) as a practical standpoint in the treatment of lymphedema of lower limbs in order to create an efficacious dose of Coumarin, Benzopyrones and Ginkolidi. CLINICAL: We investigated a population of 76 patients treated in an open-label study for six-eight months with a dosage of Coumarin 60 mg/daily + Gingko Biloba 40 mg/daily + Melilotus 40 mg/daily.

CONCLUSION

This trilogy induced a very significant improvement in lymphedema (centimeter-aspect) both in functional symptoms (pain heaviness in affected limbs) and physical signs (edema, episodes of infection). Tolerance of long term treatment was good and the improvement was observed from the third month of treatment.

Dose-dependent visible effect on mice Langerhans cell membrane markers

Ultraviolet B and psoralen plus UVA treatment induce antigenic and enzymatic changes in Langerhans cells (LC). The aim of this study was to investigate the visible (VIS) effect on mice LC surface markers. As visible source, a slide projector equipped with a 150-W tungsten lamp, emitting between 400 and 740 nm (maximum at 580 nm) was used. Mice (BALB/c and C3H) were divided into groups, each irradiated with visible single fixed doses (ranging from 10 to 1000 J/cm2). The mice backs were shaved before irradiation. Skin biopsies obtained immediately after irradiation were processed for immunofluorescence and electron microscopy. Immunofluorescent studies showed: 1) a complete depletion of LC membrane markers at a dose of 700 J/cm2; 2) no effect at visible doses ranging between 0 and 75 J/cm2; 3) a dose-dependent effect with doses between 100 and 700 J/cm2. Electron microscopy revealed no cellular damage of LC at the visible doses administered.