Visfatin/extracellular-nicotinamide-phosphoribosyltranferase-(eNampt) is a multifaceted adipokine enhanced in type-2-diabetes and obesity. Visfatin/eNampt cause in vitro endothelial dysfunction and vascular inflammation, although whether the same effects are achieved in vivo is unknown. Toll-like receptor-4 (TLR4), a main surface pattern recognition receptor of innate immune system is a potential target for visfatin/eNampt. We studied its capacity to generate vascular dysfunction in vivo, focusing on TLR4 role and downstream activation of nod-like-receptor-protein-3 (NLRP3)-inflammasome. 4 month-old C57BL/6 mice were exposed to 7 days infusion of visfatin/eNampt, alone or together with FK 866 (Nampt enzymatic inhibitor), CLI 095 (TLR4 blocker), MCC 950 (NLRP3-inflammasome inhibitor), or anakinra (interleukin(IL)-1-receptor antagonist). Endothelial dysfunction was tested in isolated microvessels. In human umbilical endothelial cells (HUVEC), proteins related to the NLRP3-inflammasome phosphorylated p-65, NLRP3, caspase-1, pro-IL-1β, and mature IL-1β were determined by Western blot, while the inflammasome related apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC-specks) was studied by immunofluorescence. Impaired endothelium-dependent relaxations were observed in isolated mesenteric microvessels from visfatin/eNampt-infused mice. This effect was attenuated by co-treatment with FK 866 or CLI 095, supporting a role for Nampt enzymatic activity and TLR4 activation. Moreover, cultured HUVEC exposed to visfatin/eNampt showed higher expression and activation of NLRP3-inflammasome. Again, this effect relied on Nampt enzymatic activity and TLR4 activation, and it was abrogated by the inflammasome assembly blockade with MCC 950. The endothelial dysfunction evoked by visfatin/eNampt infusion in vivo was also sensitive to both MCC 950 and anakinra treatments, suggesting that the NLRP3-inflammasome-driven tissular release of IL-1β is the final mediator of endothelial damage. We conclude that Visfatin/eNampt produces in vivo vascular dysfunction in mice by a Nampt-dependent TLR4-mediated pathway, involving NLRP3-inflammasome and paracrine IL-1β. Thus, those targets may become therapeutic strategies for attenuating the adipokine-mediated vascular dysfunction associated to obesity and/or type-2-diabetes.

Colorectal cancer remains a main cause of deaths worldwide, and novel agents are being searched to treat this disease. Polyphenols have emerged as promising therapeutic tools in cancer. Resveratrol (3,5,4′-trihydoxy-trans-stilbene) induces cell death in different tumor cell lines, and it also stimulates the proliferation of specific breast and prostate cancer cell lines. Here, we studied the impact of resveratrol over a 100-fold concentration range on cell death and proliferation of HT-29 colorectal adenocarcinoma cells. After 96 h of treatment, a biphasic pattern was observed. At lower concentrations (1 and 10 μmol/l), resveratrol increased the cell number, as did the polyphenol quercetin. At 50 or 100 μmol/l, resveratrol reduced the cell number and increased the percentage of apoptotic or necrotic cells, thus indicating cytotoxicity. On HCT116 colon cancer cells, however, no proliferative properties of resveratrol were observed. Resveratrol-induced cytotoxicity on HT-29 cells was associated with NADPH oxidase activation and increased levels of histone γH2AX, a marker of DNA damage, paralleled by enhanced sirtuin 6 levels, likely as a repair mechanism. Overall, resveratrol may be an effective tool in anti-tumor chemotherapy. However, since under some conditions it may favor tumor cell growth, appropriate local concentrations must be achieved to minimize unwanted effects of resveratrol.

Background and aims: Targeting inflammation is nowadays considered as a challenging pharmacological strategy to prevent or delay the development of vascular diseases. Angiotensin-(1-7) is a member of the renin-angiotensin system (RAS) that binds Mas receptors and has gained growing attention in the last years as a regulator of vascular homeostasis. Here, we explored the capacity of Ang-(1-7) to counteract human aortic smooth muscle cell (HASMC) inflammation triggered by RAS-dependent and –independent stimuli, such as Ang II or interleukin (IL)-1. Methods and Results: In cultured HASMC, the expression of iNOS and the release of nitric oxide were stimulated by both Ang II and IL-1, as determined by Western blot and indirect immunofluorescence or the Griess method, respectively. iNOS induction was inhibited by Ang-(1-7) in a concentration-dependent manner. This effect was equally blocked by two different Mas receptor antagonists, A779 and D-Pro7-Ang-(1-7), suggesting the participation of a unique Mas receptor subtype. Using pharmacological inhibitors, the induction of iNOS was proven to rely on the consecutive upstream activation of NADPH oxidase and NF-B. Indeed, Ang-(1-7) markedly inhibited the activation of the NADPH oxidase and subsequently of NF-B, as determined by lucigenin-derived chemiluminiscence and electromobility shift assay, respectively. Conclusion: Ang-(1-7) can act as a counter-regulator of the inflammation of vascular smooth muscle cells triggered by Ang II, but also by other stimuli beyond the RAS. Activating or mimicking the Ang-(1-7)/Mas axis may represent a pharmacological opportunity to attenuate the pro-inflammatory environment that promotes and sustains the development of vascular diseases.

Cardiovascular diseases (CVDs), including atherosclerosis, are globally the leading cause of death. Key factors contributing to onset and progression of atherosclerosis include the pro-inflammatory cytokines Interferon (IFN)α and IFNγ and the Pattern Recognition Receptor (PRR) Toll-like receptor 4 (TLR4). Together, they trigger activation of Signal Transducer and Activator of Transcription (STAT)s. Searches for compounds targeting the pTyr-SH2 interaction area of STAT3, yielded many small molecules, including STATTIC and STX-0119. However, many of these inhibitors do not seem STAT3-specific. We hypothesized that multi-STAT-inhibitors that simultaneously block STAT1, STAT2, and STAT3 activity and pro-inflammatory target gene expression may be a promising strategy to treat CVDs. Using comparative in silico docking of multiple STAT-SH2 models on multi-million compound libraries, we identified the novel multi-STAT inhibitor, C01L_F03. This compound targets the SH2 domain of STAT1, STAT2, and STAT3 with the same affinity and simultaneously blocks their activity and expression of multiple STAT-target genes in HMECs in response to IFNα. The same in silico and in vitro multi-STAT inhibiting capacity was shown for STATTIC and STX-0119. Moreover, C01L_F03, STATTIC and STX-0119 were also able to affect genome-wide interactions between IFNγ and TLR4 by commonly inhibiting pro-inflammatory and pro-atherogenic gene expression directed by cooperative involvement of STATs with IRFs and/or NF-κB. Moreover, we observed that multi-STAT inhibitors could be used to inhibit IFNγ+LPS-induced HMECs migration, leukocyte adhesion to ECs as well as impairment of mesenteric artery contractility. Together, this implicates that application of a multi-STAT inhibitory strategy could provide great promise for the treatment of CVDs.

Pyrethroids are neurotoxicants for animals, showing a pattern of toxic action on the nervous system. Flumethrin, a synthetic pyrethroid, is used against ectoparasites in domestic animals, plants, and for public health. This compound has been shown to be highly toxic to bees, while its effects on other animals have been less investigated. However, in vitro studies to evaluate cytotoxicity are scarce, and the mechanisms associated with this effect at the molecular level are still unknown. This study aimed to investigate the oxidative stress and cell death induction in SH-SY5Y neuroblastoma cells in response to flumethrin exposure (1–1000 µM). Flumethrin induced a significant cytotoxic effect, as evaluated by MTT and LDH leakage assays, and produced an increase in the biomarkers of oxidative stress as reactive oxygen species and nitric oxide (ROS and NO) generation, malondialdehyde (MDA) concentration, and caspase-3 activity. In addition, flumethrin significantly increased apoptosis-related gene expressions (Bax, Casp-3, BNIP3, APAF1, and AKT1) and oxidative stress and antioxidative (NFκB and SOD2) mediators. The results demonstrated, by biochemical and gene expression assays, that flumethrin induces oxidative stress and apoptosis, which could cause DNA damage. Detailed knowledge obtained about these molecular changes could provide the basis for elucidating the molecular mechanisms of flumethrin-induced neurotoxicity.

Hypoxia at altitudes above 3000 m poses a significant threat to organ health and physiological homeostasis, particularly in metabolically active tissues such as the brain. Many of the cellular alterations induced by hypoxia are associated with the excessive generation of reactive oxygen species (ROS) and the resulting oxidative stress. In this study, we investigated the effects of exposure duration and altitude levels on oxidative homeostasis in the rat hypothalamus, cortex, hippocampus, and striatum. We assessed ROS production, malondialdehyde (MDA) levels, the antioxidant activities of superoxide dismutase (SOD), and catalase, as well as molecular biomarkers of oxidative stress, cell death, and inflammation. Our findings demonstrated that ROS, MDA and SOD levels increased across all brain regions, particularly in response to higher altitude exposure. Conversely, catalase activity decreased under the same conditions. At the molecular level, we observed overexpression of key biomarkers related to oxidative stress, cell death, and inflammation, especially at extreme altitudes. Furthermore, these effects were most pronounced in the hippocampus, cortex, and striatum. In conclusion, our data indicate that hypoxic exposure at higher altitudes significantly contributes to the oxidative disruption of brain homeostasis in rats.