Use of Vagus Nerve Stimulation and Vagal Maneuvers as Adjuvant Therapy for COVID-19 Patients

At present there is no effective specific antiviral drug to treat the ongoing COVID-19 pandemic that has already infected millions of individual and caused hundreds of thousand deaths worldwide. There is strong indication that a cytokine storm is responsible for the severity of COVID-19 patients. Pilot studies using IL-6 receptor inhibitors such as Tolicizumab have shown promising results. However, since the cytokine storm is a complex systemic inflammatory response involving multiple cytokines it can be hypothesized that a “paninhibition” of cytokines and/or cytokine receptors will be more effective. However, at the same time this strategy may cause more adverse effects. In this article, we propose the application of Vagus Nerve Stimulation (NVS) and/or some forms of vagal maneuvers as adjuvant therapies to prevent and/or mitigate the cytokine response in COVID-19 patients. This proposal is based on the ability of NVS and to decrease the production of IL-6 and other cytokines. The potential application of the diving response (one form of vagal maneuver), that has been shown to confer intrinsic resistance to inflammation in the blood of diving mammals, is also discussed as adjuvant therapy for COVID-19 patients.   Doi: 10.28991/SciMedJ-2021-03-SI-2 Full Text: PD

Particulate matter cytotoxicity in cultured SH-SY5Y cells is modulated by simvastatin: Toxicological assessment for oxidative damage

Epidemiological studies have shown a positive correlation between environmental particulate matter and adverse health effects. In particular, residual oil fly ash (ROFA) induces inflammation and reactive oxygen species (ROS), exerting not only local, but also systemic adverse effects. Previously, in an experimental animal model, we found that simvastatin (Sv) pretreatment was effective in preventing ROFA induced lung inflammation. Herein, using the human neuroblastoma SH-SY5Y cell line as a neurotoxicity in vitro model, we studied the potential Sv protective effect on ROFA cytotoxicity. We evaluated cell viability by the MTT assay, superoxide anion generation by NBT test, Nrf2 activation by immunofluorescence, apoptosis by cleaved-PARP and active-caspase 3 expressions, and senescence by b-galactosidase activity. SH-SY5Y cells exposed to ROFA (10 and 50mg/ml) for 24 h showed decreased cell viability, increased superoxide anion generation, apoptosis and senescence. Pretreatment with Sv (1mM) for 6 days, restored cell viability to basal levels, reduced ROFA-induced O2 generation as well as the number of apoptotic and senescent cells. Sv pretreatment stimulated the basal and ROFA-induced levels of Nrf2 nuclear translocation suggesting that activation of the cellular antioxidant defense system prevented particle-induced oxidative stress. In parallel, rescue experiments with mevalonate did not modify the effects of SV pretreatment in any of the parameters evaluated in this study. We conclude that simvastatin may provide neuroprotection against air particulate matter-induced neurotoxicity independently of its ability to inhibit cholesterol synthesis.Fil: Ferraro, Sebastián Ariel. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología. Centro de Estudios en Salud y Medio Ambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Astort, Francisco. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología. Centro de Estudios en Salud y Medio Ambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Yakisich, Juan Sebastian. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología. Centro de Estudios en Salud y Medio Ambiente; ArgentinaFil: Tasat, Deborah Ruth. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología. Centro de Estudios en Salud y Medio Ambiente; Argentina. Universidad de Buenos Aires. Facultad de Odontología. Cátedra de Histología y Embriología; Argentin

Direct and indirect air particle cytotoxicity in human alveolar epithelial cells

Air particulate matter has been associated with adverse impact on the respiratory system leading to cytotoxic and proinflammatory effects. The biological mechanisms behind these associations may be initiated by inhaled small size particles, particle components (soluble fraction) and/or mediators released by particle-exposed cells (conditioned media). The effect of Urban Air Particles from Buenos Aires (UAP-BA) and Residual Oil Fly Ash (ROFA) a surrogate of ambient air pollution, their soluble fractions (SF) and conditioned media (CM) on A549 lung epithelial cells was examined. After 24h exposure to TP (10 and 100 μg/ml), SF or CM, several biological parameters were assayed on cultured A549 cells. We tested cell viability by MTT, superoxide anion (O2-) generation by NBT and proinflammatory cytokine (TNF α, IL-6 and IL-8) production by ELISA. UAP-BA particles or its SF (direct effect) did not modify cell viability and generation of O2- for any of the doses tested. On the contrary, UAP-BA CM (indirect effect) reduced cell viability and increased both generation of O2- and IL-8 production. Exposure to ROFA particles, SF or ROFA CM reduced proliferation and O2- but, stimulated IL-8. It is worth to note that UAP-BA and ROFA depicted distinct effects on particle-exposed A549 cells implicating morphochemical dependence. These in vitro findings support the hypothesis that particle-induced lung inflammation and disease may involve lung-derived mediators.Fil: Orona, Nadia Soledad. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Astort, Francisco. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Maglione, Guillermo Alberto. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Saldiva, P. H. N.. Iira, National Research Council, Brazil; . Institute of Integrated Risk Analysis; BrasilFil: Yakisich, J. S.. Karolinska Huddinge Hospital. Karolinska Institutet; SueciaFil: Tasat, Deborah Ruth. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Universidad de Buenos Aires. Facultad de Odontología; Argentin

Chemoresistance of Lung Cancer Cells: 2D and 3D In Vitro Models for Anticancer Drug Screening

Chemoresistance of lung cancer cells is a key factor that limits the treatment of lung cancer patients. Patients may initially respond to standard chemotherapy, but this is often followed by rapid development of drug resistance and disease progression. Tumor heterogeneity and the presence of putative cancer stem-like cells (CS-LCs) provide a viable explanation for the chemoresistance of several types of tumors. In this book chapter, we will first describe the current knowledge of the role of both tumor heterogeneity and CS-LCs in lung cancer chemoresistance, tumor progression and metastasis. Next, we will discuss ongoing strategies at the in vitro level to screen for more effective anticancer drugs. We will specifically focus in three-dimensional (3D) culture systems (Spheroids and tumorspheres) and their application in anticancer drug discovery for lung cancer

The Biguanides Metformin and Buformin in Combination with 2-Deoxy-glucose or WZB-117 Inhibit the Viability of Highly Resistant Human Lung Cancer Cells

The biguanides metformin (MET) and to a lesser extent buformin (BUF) have recently been shown to exert anticancer effects. In particular, MET targets cancer stem cells (CSCs) in a variety of cancer types but these compounds have not been extensively tested for combination therapy. In this study, we investigated in vitro the anticancer activity of MET and BUF alone or in combination with 2-deoxy-D-glucose (2-DG) and WZB-117 (WZB), which are a glycolysis and a GLUT-1 inhibitor, respectively, in H460 human lung cancer cells growing under three different culture conditions with varying degrees of stemness: (1) routine culture conditions (RCCs), (2) floating lung tumorspheres (LTSs) that are enriched for stem-like cancer cells, and (3) adherent cells under prolonged periods (8-12 days) of serum starvation (PPSS). These cells are highly resistant to conventional anticancer drugs such as paclitaxel, hydroxyurea, and colchicine and display an increased level of stemness markers. As single agents, MET, BUF, 2-DG, and WZB-117 potently inhibited the viability of cells growing under RCCs. Both MET and BUF showed a strong synergistic effect when used in combination with 2-DG. A weak potentiation was observed when used with WZB-117. Under RCCs, H460 cells were more sensitive to MET and BUF and WZB-117 compared to nontumorigenic Beas-2B cells. While LTSs were less sensitive to each single drug, both MET and BUF in combination with 2-DG showed a strong synergistic effect and reduced cell viability to similar levels compared to the parental H460 cells. Adherent cells growing under PPSS were also less sensitive to each single drug, and MET and BUF showed a strong synergistic effect on cell viability in combination with 2-DG. Overall, our data demonstrates that the combination of BGs with either 2-DG or WZB-117 has “broad-spectrum” anticancer activities targeting cells growing under a variety of cell culture conditions with varying degrees of stemness. These properties may be useful to overcome the chemoresistance due to intratumoral heterogeneity found in lung cancer

Selective and Irreversible Induction of Necroptotic Cell Death in Lung Tumorspheres by Short-Term Exposure to Verapamil in Combination with Sorafenib

The presence of highly resistant cancer cells and the toxicity to normal cells are key factors that limit chemotherapy. Here, we used two models of highly resistant lung cancer cells: (1) adherent cells growing under prolonged periods of serum starvation (PPSS) and (2) cells growing as floating tumorspheres (FTs) to evaluate the effect of Verapamil (VP) in combination with Sorafenib (SF). Compared to cells growing under routine culture conditions (RCCs), PPPS cells or FTs were highly sensitive to short-term exposure (24 h) to VP 100 μM + SF 5 μM (VP100 + SF5). Recovery experiments exposing cells to VP100 + SF5 for 24 h followed by incubation in drug-free media for 48 h demonstrated that while PPSS as well as FT cells were unable to recover, cancer cells and the noncancerous cell line Beas-2B growing under RCCs were less sensitive and were also able to recover significantly. VP100 + SF5 induced significant changes in the expression of protein associated with apoptosis, autophagy, and to a lesser extent necroptosis. Coincubation experiments with z-VAD-FMK, necrostatin 1, or chloroquine showed evidence that necroptosis played a central role. Our data demonstrates that highly resistant cancer cells can be selectively eliminated by VP + SF and that necroptosis plays a central role

Ionophores: Potential Use as Anticancer Drugs and Chemosensitizers

Ion homeostasis is extremely important for the survival of both normal as well as neoplastic cells. The altered ion homeostasis found in cancer cells prompted the investigation of several ionophores as potential anticancer agents. Few ionophores, such as Salinomycin, Nigericin and Obatoclax, have demonstrated potent anticancer activities against cancer stem-like cells that are considered highly resistant to chemotherapy and responsible for tumor relapse. The preclinical success of these compounds in in vitro and in vivo models have not been translated into clinical trials. At present, phase I/II clinical trials demonstrated limited benefit of Obatoclax alone or in combination with other anticancer drugs. However, future development in targeted drug delivery may be useful to improve the efficacy of these compounds. Alternatively, these compounds may be used as leading molecules for the development of less toxic derivatives

Direct and indirect effect of air particles exposure induce Nrf2-dependent cardiomyocyte cellular Response In Vitro

Air particulate matter has been associated with adverse effects in the cardiorespiratory system leading to cytotoxic and pro-inflammatory effects. Particulate matter-associated cardiac effects may be direct or indirect. While direct interactions may occur when inhaled ultrafine particles and/or particle components cross the air?blood barrier reaching the cardiac tissue, indirect interactions may occur as the result of pulmonary inflammation and consequently the release of inflammatory and oxidative mediators into the blood circulation. The aim of the study is to investigate the direct or indirectly the effect of Urban Air particles from downtown Buenos Aires (UAP-BA) and residual oil fly ash (ROFA), a surrogate of ambient air pollution, on cardiomyocytes (HL-1 cells). HL-1 cultured cells were directly exposed to particulate matter [UAP-BA (10?200 µg/ml), ROFA (1?100 µg/ml)] or indirectly exposed to conditioned media (CM) from particle-exposed alveolar macrophages (AM). Metabolic activity, reactive oxygen species (ROS), and Nrf2 expression were assessed by MTT, DHR 123, and immunocytochemistry techniques, respectively. We found that direct exposure of cardiomyocytes to UAP-BA or ROFA increased ROS generation but the oxidative damage did not alter metabolic activity likely by a concomitant increase in the cytoplasmic and nuclear Nrf2 expression. However, indirect exposure through CM caused a marked reduction on cardiac metabolic activity probably due to the rise in ROS generation without Nrf2 translocation into the cell nuclei. In this in vitro model, our results indicate both direct and indirect PM effects on cardiomyocytes cells in culture. Our findings employing lung and cardiomyocytes cells provide support to the hypothesis that particle-induced cardiac alteration may possibly involve lung-derived mediators.Fil: Orona, Nadia Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología. Centro de Estudios en Salud y Medio Ambiente; ArgentinaFil: Astort, Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología. Centro de Estudios en Salud y Medio Ambiente; ArgentinaFil: Maglione, Guillermo Alberto. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología. Centro de Estudios en Salud y Medio Ambiente; Argentina. Universidad de Buenos Aires. Facultad de Odontología. Cátedra de Histología y Embriología; ArgentinaFil: Yakisich, Juan Sebastian. Hampton University; Estados UnidosFil: Tasat, Deborah Ruth. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología. Centro de Estudios en Salud y Medio Ambiente; Argentina. Universidad de Buenos Aires. Facultad de Odontología. Cátedra de Histología y Embriología; Argentin