Alpha Lipoic Acid as a Potential Treatment for COVID-19 - A Hypothesis

2020 ◽  
Vol 19 (2) ◽  
pp. 172-175
Author(s):  
Serkan Sayıner ◽  
Ahmet Özer Şehirli ◽  
Nedime Serakıncı

SARS-CoV-2 infection has led to COVID-19 outbreak worldwide. To date, a specific antiviral drug does not exist to treat the disease and control the virus. In this paper, we have explored the potential utility of alpha lipoic acid, an anti-inflammatory and antioxidant molecule, for treatment. Alpha lipoic acid exhibits strong antioxidant properties and modulates the immune system by regulating T cell activation making it a useful therapeutic candidate for cytokine storm triggering SARS-CoV-2 infection. In the present communication, we focused on the therapeutic potential of ALA with respect to its potential role on reducing the severity of symptoms and the adverse effects of other antiviral drugs used. We consider different mechanisms by which modulating ACE2 levels after virus replication and preventing cytokine storm and also focus on a new therapeutic venue that utilizes ALA.

2019 ◽  
Vol 16 (32) ◽  
pp. 214-227
Author(s):  
Rebeca CAPARICA ◽  
Erica Aparecida ROZISCA ◽  
Julio César MACENA ◽  
Laís de Almeida CAMPOS ◽  
Diana Fortkamp GRIGOLETTO

Melatonin was discovered by Lerner and Coworkers in 1958, and is the main product secreted by the pineal gland. It is a phylogenetically highly conserved molecule and one of the oldest biological signaling mechanisms. It presents several biological functions, among them the most studied is the regulation of the sleep cycle and wakefulness. In addition, melatonin acts as an immunomodulatory, antioxidant molecule and has anticarcinogenic potential. It also participates in the regulation of mood and control of seasonal reproduction. Melatonin is a potent free radical scavenger and several of its metabolites have the ability to remove singlet oxygen, superoxide radicals, hydroperoxides, hydroxyl radicals and radical lipid peroxides. It easily penetrates cell membranes by being soluble in aqueous and organic media, playing a key role in cell biology. Although their activities are interesting for therapy, their low availability, short half-life, and rapid metabolism restrict their use. In this sense, nanotechnology is a tool that has been studied for the elaboration of systems that improve the pharmacokinetic and pharmacodynamic characteristics of melatonin, in order to potentiate its application in biological models. This review summarizes several studies published in recent years that have shown the most numerous biological activities of melatonin and the improvement of their therapeutic potential through nanotechnology.


2014 ◽  
Vol 34 (suppl_1) ◽  
Author(s):  
Xuedong Tong ◽  
Regis Moreau ◽  
Qiaozhu Su

Activation of the sterol regulatory element-binding proteins (SREBPs), a step regulated by a cluster of ER-resident proteins, Insig-1, Insig-2 and SCAP, is rate limiting in hepatic de novo lipogenesis. We previously reported that feeding R-alpha-lipoic acid (LA) to ZDF (fa/fa) rats improves severe hypertriglyceridemia and lowers abdominal fat mass by inhibiting expression of genes involved in hepatic long-chain fatty acids and triacylglycerol syntheses. In this study, we characterized a novel mechanism of action of LA that explains its triacylglycerol lowering properties. Dietary LA activates liver specific transcription factor cAMP responsive element binding protein H (CREBH), which in turn enhances transcription and translation of Insig-1 and Insig-2. Chromatin immunoprecipitation (ChIP) assay demonstrated interaction between CREBH and the promoter of Insig-2 but not Insig-1. The increased abundance of Insig-1 and Insig-2 proteins contributes to sequester SREBP-1c and SREBP-2 in the ER and prevents their translocation to the Golgi apparatus where they would become activated. As a consequence, mRNA expression of genes involved in fatty acid and cholesterol synthesis, including FASN, ACC, SCD-1, HMGCR and LDL receptor, were significantly decreased in LA-fed animals versus pair-fed controls. Concomitantly, the assembly and secretion of very-low-density lipoproteins (VLDL) by primary hepatocytes were suppressed in the LA-fed ZDF rats as indicated by the decrease in VLDL-associated apolipoprotein B and apolipoprotein E. In vitro, treating a rat McA-RH7777 hepatoma cells with LA (200 micromole) activated CREBH, induced expression of Insig-1 and Insig-2, and hindered the palmitic acid-induced synthesis of triacylglycerol. This study provides new mechanistic insight into the triacylglycerol lowering properties of LA and supports the therapeutic potential of LA against hypertriglyceridemia.


2020 ◽  
Vol 8 (2) ◽  
pp. e001521
Author(s):  
Javier Arranz-Nicolás ◽  
Miguel Martin-Salgado ◽  
Cristina Rodríguez-Rodríguez ◽  
Rosa Liébana ◽  
Maria C Moreno-Ortiz ◽  
...  

BackgroundThe inhibitory functions triggered by the programmed cell death-1 (PD-1) receptor following binding to its ligand (PD-L1) protect healthy organs from cytotoxic T cells, and neutralize antitumor T cell attack. Antibody-based therapies to block PD-1/PD-L1 interaction have yielded notable results, but most patients eventually develop resistance. This failure is attributed to CD8+ T cells achieving hyporesponsive states from which recovery is hardly feasible. Dysfunctional T cell phenotypes are favored by a sustained imbalance in the diacylglycerol (DAG)- and Ca2+-regulated transcriptional programs. In mice, DAG kinase ζ (DGKζ) facilitates DAG consumption, limiting T cell activation and cytotoxic T cell responses. DGKζ deficiency facilitates tumor rejection in mice without apparent adverse autoimmune effects. Despite its therapeutic potential, little is known about DGKζ function in human T cells, and no known inhibitors target this isoform.MethodsWe used a human triple parameter reporter cell line to examine the consequences of DGKζ depletion on the transcriptional restriction imposed by PD-1 ligation. We studied the effect of DGKζ deficiency on PD-1 expression dynamics, as well as the impact of DGKζ absence on the in vivo growth of MC38 adenocarcinoma cells.ResultsWe demonstrate that DGKζ depletion enhances DAG-regulated transcriptional programs, promoting interleukin-2 production and partially counteracting PD-1 inhibitory functions. DGKζ loss results in limited PD-1 expression and enhanced expansion of cytotoxic CD8+ T cell populations. This is observed even in immunosuppressive milieus, and correlates with the reduced ability of MC38 adenocarcinoma cells to form tumors in DGKζ-deficient mice.ConclusionsOur results, which define a role for DGKζ in the control of PD-1 expression, confirm DGKζ potential as a therapeutic target as well as a biomarker of CD8+ T cell dysfunctional states.


2018 ◽  
Vol 215 (4) ◽  
pp. 1101-1113 ◽  
Author(s):  
Marc-Werner Dobenecker ◽  
Joon Seok Park ◽  
Jonas Marcello ◽  
Michael T. McCabe ◽  
Richard Gregory ◽  
...  

Differentiation and activation of T cells require the activity of numerous histone lysine methyltransferases (HMT) that control the transcriptional T cell output. One of the most potent regulators of T cell differentiation is the HMT Ezh2. Ezh2 is a key enzymatic component of polycomb repressive complex 2 (PRC2), which silences gene expression by histone H3 di/tri-methylation at lysine 27. Surprisingly, in many cell types, including T cells, Ezh2 is localized in both the nucleus and the cytosol. Here we show the presence of a nuclear-like PRC2 complex in T cell cytosol and demonstrate a role of cytosolic PRC2 in T cell antigen receptor (TCR)–mediated signaling. We show that short-term suppression of PRC2 precludes TCR-driven T cell activation in vitro. We also demonstrate that pharmacological inhibition of PRC2 in vivo greatly attenuates the severe T cell–driven autoimmunity caused by regulatory T cell depletion. Our data reveal cytoplasmic PRC2 is one of the most potent regulators of T cell activation and point toward the therapeutic potential of PRC2 inhibitors for the treatment of T cell–driven autoimmune diseases.


2017 ◽  
Vol 313 (2) ◽  
pp. L406-L415 ◽  
Author(s):  
Gene T. Yocum ◽  
Damian L. Turner ◽  
Jennifer Danielsson ◽  
Matthew B. Barajas ◽  
Yi Zhang ◽  
...  

Emerging evidence indicates that hypnotic anesthetics affect immune function. Many anesthetics potentiate γ-aminobutyric acid A receptor (GABAAR) activation, and these receptors are expressed on multiple subtypes of immune cells, providing a potential mechanistic link. Like immune cells, airway smooth muscle (ASM) cells also express GABAARs, particularly isoforms containing α4-subunits, and activation of these receptors leads to ASM relaxation. We sought to determine if GABAAR signaling modulates the ASM contractile and inflammatory phenotype of a murine allergic asthma model utilizing GABAAR α4-subunit global knockout (KO; Gabra40/0) mice. Wild-type (WT) and Gabra4 KO mice were sensitized with house dust mite (HDM) antigen or exposed to PBS intranasally 5 days/wk for 3 wk. Ex vivo tracheal rings from HDM-sensitized WT and Gabra4 KO mice exhibited similar magnitudes of acetylcholine-induced contractile force and isoproterenol-induced relaxation ( P = not significant; n = 4). In contrast, in vivo airway resistance (flexiVent) was significantly increased in Gabra4 KO mice ( P < 0.05, n = 8). Moreover, the Gabra4 KO mice demonstrated increased eosinophilic lung infiltration ( P < 0.05; n = 4) and increased markers of lung T-cell activation/memory (CD62L low, CD44 high; P < 0.01, n = 4). In vitro, Gabra4 KO CD4+ cells produced increased cytokines and exhibited increased proliferation after stimulation of the T-cell receptor as compared with WT CD4+ cells. These data suggest that the GABAAR α4-subunit plays a role in immune cell function during allergic lung sensitization. Thus GABAAR α4-subunit-specific agonists have the therapeutic potential to treat asthma via two mechanisms: direct ASM relaxation and inhibition of airway inflammation.


2009 ◽  
Vol 54 (5) ◽  
pp. 391-398 ◽  
Author(s):  
Stéliana Ghibu ◽  
Carole Richard ◽  
Catherine Vergely ◽  
Marianne Zeller ◽  
Yves Cottin ◽  
...  

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 4975-4975
Author(s):  
Wouter Korver ◽  
Xiaoxian Zhao ◽  
Shweta Singh ◽  
Cecile Pardoux ◽  
Ishita Barman ◽  
...  

Abstract NTB-A is a CD2-related cell surface protein expressed on lymphoid cells including B-lymphocytes from Chronic Lymphocytic Leukemia (CLL) and lymphoma patients. We have generated a series of mAbs against NTB-A and assessed their therapeutic potential in preclinical models. Selected mAbs to NTB-A were further tested in functional Complement Dependent Cytotoxicity (CDC) and Antibody Dependent Cellular Cytotoxicty (ADCC) assays in cell lines and B lymphocytes freshly isolated from CLL and lymphoma patients. Potent cytotoxic activity was demonstrated against B cells isolated from CLL patients and B lymphoma cell lines. Chimeric anti-NTB-A mAbs demonstrated anti-tumor activity equal to rituximab against CA46 human lymphoma xenografts in nude mice at a low dose. In a chimpanzee safety study, a single dose of lead anti-NTB-A mAb 994.1 resulted in near-complete depletion of peripheral lymphocytes while having a minimal effect on T cell activation. Taken together, these results demonstrate NTB-A as a promising target with an acceptable safety profile for immunotherapy of leukemia and lymphomas.


2021 ◽  
Author(s):  
Dominik Burri ◽  
Mihaela Zavolan

During pre-mRNA maturation 3' end processing can occur at different polyadenylation sites in the 3' untranslated region (3' UTR) to give rise to transcript isoforms that differ in the length of their 3' UTRs. Longer 3' UTRs contain additional cis-regulatory elements that impact the fate of the transcript and/or of the resulting protein. Extensive alternative polyadenylation (APA) has been observed in cancers, but the mechanisms and roles remain elusive. In particular, it is unclear whether the APA occurs in the malignant cells or in other cell types that infiltrate the tumor. To resolve this, we developed a computational method, called SCUREL, that quantifies changes in 3' UTR length between groups of cells, including cells of the same type originating from tumor and control tissue. We used this method to study APA in human lung adenocarcinoma (LUAD). SCUREL relies solely on annotated 3' UTRs and on control systems, such as T cell activation and spermatogenesis gives qualitatively similar results at much greater sensitivity compared to the previously published scAPA method. In the LUAD samples, we find a general trend towards 3' UTR shortening not only in cancer cells compared to the cell type of origin, but also when comparing other cell types from the tumor vs. the control tissue environment. However, we also find high variability in the individual targets between patients. The findings help to understand the extent and impact of APA in LUAD, which may support improvements in diagnosis and treatment.


2021 ◽  
Vol 6 (62) ◽  
pp. eabg4925
Author(s):  
Rahel Frick ◽  
Lene S. Høydahl ◽  
Jan Petersen ◽  
M. Fleur du Pré ◽  
Shraddha Kumari ◽  
...  

Antibodies specific for peptides bound to human leukocyte antigen (HLA) molecules are valuable tools for studies of antigen presentation and may have therapeutic potential. Here, we generated human T cell receptor (TCR)–like antibodies toward the immunodominant signature gluten epitope DQ2.5-glia-α2 in celiac disease (CeD). Phage display selection combined with secondary targeted engineering was used to obtain highly specific antibodies with picomolar affinity. The crystal structure of a Fab fragment of the lead antibody 3.C11 in complex with HLA-DQ2.5:DQ2.5-glia-α2 revealed a binding geometry and interaction mode highly similar to prototypic TCRs specific for the same complex. Assessment of CeD biopsy material confirmed disease specificity and reinforced the notion that abundant plasma cells present antigen in the inflamed CeD gut. Furthermore, 3.C11 specifically inhibited activation and proliferation of gluten-specific CD4+ T cells in vitro and in HLA-DQ2.5 humanized mice, suggesting a potential for targeted intervention without compromising systemic immunity.


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