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Background/Aims: The physiological phenotype of individuals can influence and shape reallife phenomena in that it can contribute to the development of specific characteristics that can affect the immune response to specific stimuli. In this study we aimed to understand whether the sphingosine/sphingosine-1-phoshate (S1P) axis can modulate the immunotype of circulating cells. Methods: To pursue this goal, we performed bioinformatic analyses of public datasets. Results: The transcriptomic profile of healthy subjects of GSE192829 dataset identified two clusters with different transcriptional repertoire. Cluster 1 expressed higher levels of enzymes for S1P formation than cluster 0 which was characterized by enzymes that lead to ceramide formation, which represent the opposite metabolic direction. Inference analysis showed that cluster 1 was higher populated by monocytes, CD4+ T and B cells than cluster 0. Of particular interest was the phenotype of the monocytes in cluster 1 which showed an immunosuppressive nature compared to those in cluster 0. The role of S1P signature in healthy PBMCs was confirmed with other dataset analyses, supporting that circulating monocytes positive to the ceramidase, unlike the negative ones, had an immunosuppressive phenotype characterized by hub immunosuppressive markers (i.e. TYROBP, FCER1G, SYK, SIRPA, CSF1R, AIF1, FCGR2A, CLEC7A, LYN, PLCG2, LILRs, HCK, GAB2). This hub genes well discriminated the immunotype of healthy subjects. Conclusion: In conclusion this study highlights that S1P-associated hub markers can be useful to discriminate subjects with pronounced immunosuppression. [ABSTRACT FROM AUTHOR]

Many herbal agents and medicinal plants have provided clinical interest due to their therapeutic properties, availability and lower side effects. The aim of this study was to understand the anti-bacterial activity of the combination of Pelargonium sidoides (PEL), Justicia adhatoda (ADH) and N-Acetyl-L-Cysteine (NAC) (NAXX). We found that NAXX had strong and long-term bacteriostatic activity, which was related to its anti-oxidant activity. Our data demonstrate that NAXX is an innovative medicinal plant-derived strategy to manage of oxidative stress- and microbial-based diseases. [ABSTRACT FROM AUTHOR]

Background/Aims: The pleiotropic lipid mediator sphingosine-1-phosphate (S1P) exerts a multitude of effects on respiratory cell physiology and pathology through five S1P receptors (S1PR1-5). Epidemiological studies proved high levels of circulating S1P in non-small cell lung cancer (NSCLC) patients. Studies in literature suggest that high levels of S1P support carcinogenesis but the exact mechanism is still elusive. The aim of this study was to understand the mechanism/s underlying S1P-mediated lung tumor cell proliferation. Methods: We used human samples of NSCLC, a mouse model of first-hand smoking and of Benzo(a)pyrene (BaP)- induced tumor-bearing mice and A549 lung adenocarcinoma cells. Results: We found that the expression of S1PR3 was also into the nucleus of lung cells in vitro, data that were confirmed in lung tissues of NSCLC patients, smoking and tumor bearing BaP-exposed mice. The intranuclear, but not the membrane, localization of S1PR3 was associated to S1P-mediated proliferation of lung adenocarcinoma cells. Indeed, the inhibition of the membrane S1PR3 did not alter tumor cell proliferation after Toll Like Receptor (TLR) 9 activation. Instead, according to the nuclear localization of sphingosine kinase (SPHK) II, the inhibition of the kinase completely blocked the endogenous S1P-induced tumor cell proliferation. Conclusion: These results prove that the nuclear S1PR3/SPHK II axis is involved in lung tumor cell proliferation, highlighting a novel molecular mechanism which could provide differential therapeutic approaches especially in non-responsive lung cancer patients. [ABSTRACT FROM AUTHOR]

Background/Aims: Sphingosine-1-phosphate (S1P) is a membrane-derived bioactive phospholipid involved in many lung physiological and pathological processes. Higher levels of S1P have been registered in a broad range of respiratory diseases, including inflammatory disorders and cancer. The aim of our study was to understand the role of S1P in healthy versus tumor cells after Toll-Like Receptors (TLRs) activation, well-known modulators of sphingolipid metabolism. Methods: Lung adenocarcinoma cells and non-pathological human fibroblasts were stimulated with unmethylated Cytosine phosphate Guanosine (CpG), the TLR9 ligand, and S1P-dependent TNF-a release was evaluated by means of ELISA. Immunofluorescence and LC-MS/MS analysis were performed to evaluate/quantify S1P generation following TLR9 activation. Results: We found that S1P was involved in TLR9-induced TNF-a release in that the inhibition of both ceramidase and sphingosine kinase I/II (SPHK I/II) significantly reduced the levels of TNF-a after TLR9 triggering in lung adenocarcinoma cells. These results were not observed in healthy fibroblasts, implying that this pathway was mainly involved in pathological conditions. Moreover, the activation of TLR4 by means of LPS did not have similar effects as in the case of CpG-stimulated TLR9. Importantly, the activation of TLR9 induced S1P generation and allowed it to interact on the outside membrane receptor S1P1 and S1P3 via the efflux through its membrane transporter SPNS2. Indeed, both the blockade of S1P3 and the transporter SPNS2 significantly reduced the activity of S1P on TNF-a release from lung adenocarcinoma cells. Conclusion: Our study identifies a novel inflammatory pathway in that TLR9 increases the pro-inflammatory cytokine release, such as TNF-a, via the induction of a ceramide/S1P imbalance in favor of S1P, adding a novel puzzle piece in TLR9-orchestrated inflammatory pathway and shedding more light on the role of the higher levels of S1P during inflammatory conditions. [ABSTRACT FROM AUTHOR]