FcεRI/PLC axis promotes anandamide synthesis and the formation of CB2-GPR55 heteromers, modulating cytokine production in mast cells.

Mast cells (MC) are crucial effectors in immediate allergic reactions. Monomeric IgE sensitizes MC and triggers various signaling responses. FcεRI/IgE/antigen crosslinking induces the release of several mediators, including bioactive lipids, but little is known about endocannabinoids (eCBs) secretion.

Potential Transcript-Based Biomarkers Predicting Clinical Outcomes of HPV-Positive Head and Neck Squamous Cell Carcinoma Patients.

Human papillomavirus (HPV)-positive Head and Neck Squamous Cell Carcinomas (HNSCC) comprise a particular cancer entity traditionally associated with better clinical outcomes. Around 25% of HNSCC are HPV positive, HPV16 being the most prevalent type. Nevertheless, close to 30% of the HPV-positive patients have an unfavorable prognosis, revealing that this type of tumor exhibits great heterogeneity leading to different clinical behaviors.

Drugs and natural products for the treatment of COVID-19 during 2020, the first year of the pandemic.

This work aimed to show which treatments showed efficacy against coronavirus disease 2019 (COVID-19); therefore, the results of 37 clinical trials started in 2020 and completed in 2021 are reviewed and discussed here. These were selected from databases, excluding vaccines, computational studies, in silico, in vitro, and those with hyperimmune sera from recovered patients. We found 34 drugs, one vitamin, and one herbal remedy with pharmacological activity against symptomatic COVID-19.

Methadone Requires the Co-Activation of μ-Opioid and Toll-Like-4 Receptors to Produce Extracellular DNA Traps in Bone-Marrow-Derived Mast Cells.

Methadone is an effective and long-lasting analgesic drug that is also used in medication-assisted treatment for people with opioid use disorders. Although there is evidence that methadone activates μ-opioid and Toll-like-4 receptors (TLR-4s), its effects on distinct immune cells, including mast cells (MCs), are not well characterized. MCs express μ-opioid and Toll-like receptors (TLRs) and constitute an important cell lineage involved in allergy and effective innate immunity responses.

Alcohol: Immunomodulatory Effects and Cancer.

Alcohol consumption has been linked to numerous pathologic conditions, including infectious diseases and several types of cancer. Alcohol exerts its modulatory effects on the immune system (IS) in a dose- and time-dependent manner. Numerous studies indicate that these alterations affect responses such as peripheral inflammation or decreased antibody production and promote chronic inflammation, leading to cell death.

Endocannabinoid modulation of allergic responses: Focus on the control of FcεRI-mediated mast cell activation.

Allergic reactions are highly prevalent pathologies initiated by the production of IgE antibodies against harmless antigens (allergens) and the activation of the high-affinity IgE receptor (FcεRI) expressed in the surface of basophils and mast cells (MCs). Research on the mechanisms of negative control of those exacerbated inflammatory reactions has been intense in recent years. Endocannabinoids (eCBs) show important regulatory effects on MC-mediated immune responses, mainly inhibiting the production of pro-inflammatory mediators.

Lysophosphatidylinositol Promotes Chemotaxis and Cytokine Synthesis in Mast Cells with Differential Participation of GPR55 and CB2 Receptors.

Mast cells (MCs) are the main participants in the control of immune reactions associated with inflammation, allergies, defense against pathogens, and tumor growth. Bioactive lipids are lipophilic compounds able to modulate MC activation. Here, we explored some of the effects of the bioactive lipid lysophosphatidylinositol (LPI) on MCs.

Toll-Like Receptor 4 Plays a Significant Role in the Biochemical and Neurological Alterations Observed in Two Distinct Mice Models of Huntington's Disease.

Toll-like receptors (TLRs) are central players in innate immunity responses. They are expressed in glial cells and neurons, and their overactivation leads to the production of proinflammatory molecules, neuroinflammation, and neural damage associated with many neurodegenerative pathologies, such as Huntington's disease (HD). HD is an inherited disorder caused by a mutation in the gene coding for the protein Huntingtin (Htt).

RIPOR2 Expression Decreased by HPV-16 E6 and E7 Oncoproteins: An Opportunity in the Search for Prognostic Biomarkers in Cervical Cancer.

High-risk human papillomavirus (HPV) infection is the main risk factor for cervical cancer (CC) development, where the continuous expression of E6 and E7 oncoproteins maintain the malignant phenotype. In Mexico, around 70% of CC cases are diagnosed in advanced stages, impacting the survival of patients. The aim of this work was to identify biomarkers affected by HPV-16 E6 and E7 oncoproteins that impact the prognosis of CC patients.

Valproic acid restricts mast cell activation by Listeria monocytogenes.

Mast cells (MC) play a central role in the early containment of bacterial infections, such as that caused by Listeria monocytogenes (L.m). The mechanisms of MC activation induced by L.

Jacareubin inhibits TLR4-induced lung inflammatory response caused by the RBD domain of SARS-CoV-2 Spike protein.

Background: COVID-19, the disease caused by SARS-CoV-2 virus infection, has been a major public health problem worldwide in the last 2 years. SARS-CoV-2-dependent activation of innate immune receptors contributes to the strong local and systemic inflammatory reaction associated with rapid disease evolution. The receptor-binding domain (RBD) of Spike (S) viral protein (S-RBD) is essential for virus infection and its interacting molecules in target cells are still under identification.

Cyclic Hypoxia Induces Transcriptomic Changes in Mast Cells Leading to a Hyperresponsive Phenotype after FcεRI Cross-Linking.

Mast cells (MCs) play important roles in tumor development, executing pro- or antitumoral functions depending on tumor type and tumor microenvironment (TME) conditions. Cyclic hypoxia (cyH) is a common feature of TME since tumor blood vessels fail to provide a continuous supply of oxygen to the tumor mass. Here, we hypothesized that the localization of MCs in cyH regions within solid tumors could modify their transcriptional profile and activation parameters.

Mast Cell-Tumor Interactions: Molecular Mechanisms of Recruitment, Intratumoral Communication and Potential Therapeutic Targets for Tumor Growth.

Mast cells (MCs) are tissue-resident immune cells that are important players in diseases associated with chronic inflammation such as cancer. Since MCs can infiltrate solid tumors and promote or limit tumor growth, a possible polarization of MCs to pro-tumoral or anti-tumoral phenotypes has been proposed and remains as a challenging research field. Here, we review the recent evidence regarding the complex relationship between MCs and tumor cells.

Mast cells and histamine are involved in the neuronal damage observed in a quinolinic acid-induced model of Huntington's disease.

Huntington´s disease (HD) is a pathological condition that can be studied in mice by the administration of quinolinic acid (QUIN), an agonist of the N-methyl-d-aspartate receptor (NMDAR) that induces NMDAR-mediated cytotoxicity and neuroinflammation. Mast cells (MCs) participate in numerous inflammatory processes through the release of important amounts of histamine (HA). In this study, we aimed to characterize the participation of MCs and HA in the establishment of neural and oxidative damage in the QUIN-induced model of HD.

Responses of Mast Cells to Pathogens: Beneficial and Detrimental Roles.

Mast cells (MCs) are strategically located in tissues close to the external environment, being one of the first immune cells to interact with invading pathogens. They are long living effector cells equipped with different receptors that allow microbial recognition. Once activated, MCs release numerous biologically active mediators in the site of pathogen contact, which induce vascular endothelium modification, inflammation development and extracellular matrix remodeling.

Signal Transduction Pathways Activated by Innate Immunity in Mast Cells: Translating Sensing of Changes into Specific Responses.

Mast cells (MCs) constitute an essential cell lineage that participates in innate and adaptive immune responses and whose phenotype and function are influenced by tissue-specific conditions. Their mechanisms of activation in type I hypersensitivity reactions have been the subject of multiple studies, but the signaling pathways behind their activation by innate immunity stimuli are not so well described. Here, we review the recent evidence regarding the main molecular elements and signaling pathways connecting the innate immune receptors and hypoxic microenvironment to cytokine synthesis and the secretion of soluble or exosome-contained mediators in this cell type.

Morphine and Fentanyl Repeated Administration Induces Different Levels of NLRP3-Dependent Pyroptosis in the Dorsal Raphe Nucleus of Male Rats via Cell-Specific Activation of TLR4 and Opioid Receptors.

Morphine promotes neuroinflammation after NOD-like receptor protein 3 (NLRP3) oligomerization in glial cells, but the capacity of other opioids to induce neuroinflammation and its relationship to the development of analgesic tolerance is unknown. We studied the effects of morphine and fentanyl on NLRP3 inflammasome activation in glial and neuronal cells in the dorsal raphe nucleus (DRN), a region involved in pain regulation. Male Wistar rats received i.

Mutant Huntingtin affects toll-like receptor 4 intracellular trafficking and cytokine production in mast cells.

Background: Huntington's disease (HD) is caused by the expression of a mutated variant of Huntingtin (mHtt), which results in the complex pathology characterized by a defective function of the nervous system and altered inflammatory responses. While the neuronal effects of mHtt expression have been extensively studied, its effects on the physiology of immune cells have not been fully described. Mast cells (MCs) are unique tissue-resident immune cells whose activation has been linked to protective responses against parasites and bacteria, but also to deleterious inflammatory allergic reactions and, recently, to neurodegenerative diseases.

Mast Cells Localize in Hypoxic Zones of Tumors and Secrete CCL-2 under Hypoxia through Activation of L-Type Calcium Channels.

Hypoxia is a condition that together with low pH, high amounts of reactive oxygen species (ROS), and increased adenosine levels characterize tumor microenvironment. Mast cells (MCs) are part of tumor microenvironment, but the effect of hypoxia on the production of MC-derived cytokines has not been fully described. Using the hypoxia marker pimonidazole in vivo, we found that MCs were largely located in the low-oxygen areas within B16-F1 mice melanoma tumors.

TLR4 Receptor Induces 2-AG-Dependent Tolerance to Lipopolysaccharide and Trafficking of CB2 Receptor in Mast Cells.

Mast cells (MCs) contribute to the control of local inflammatory reactions and become hyporesponsive after prolonged TLR4 activation by bacterial LPS. The molecular mechanisms involved in endotoxin tolerance (ET) induction in MCs are not fully understood. In this study, we demonstrate that the endocannabinoid 2-arachidonoylglycerol (2-AG) and its receptor, cannabinoid receptor 2 (CB2), play a role in the establishment of ET in bone marrow-derived MCs from C57BL/6J mice.

Chemoinformatic Analysis of Selected Cacalolides from (A. Gray) H. Rob. & Brettell and (Kunth) Cass. and Their Effects on FcεRI-Dependent Degranulation in Mast Cells.

Cacalolides are a kind of sesquiterpenoids natural compounds synthesized by (A. Gray) H. Rob.

HPV-18 E6 Oncoprotein and Its Spliced Isoform E6*I Regulate the Wnt/β-Catenin Cell Signaling Pathway through the TCF-4 Transcriptional Factor.

The Wnt/β-catenin signaling pathway regulates cell proliferation and differentiation and its aberrant activation in cervical cancer has been described. Persistent infection with high risk human papillomavirus (HR-HPV) is the most important factor for the development of this neoplasia, since E6 and E7 viral oncoproteins alter cellular processes, promoting cervical cancer development. A role of HPV-16 E6 in Wnt/β-catenin signaling has been proposed, although the participation of HPV-18 E6 has not been previously studied.

Anandamide inhibits FcεRI-dependent degranulation and cytokine synthesis in mast cells through CB and GPR55 receptor activation. Possible involvement of CB-GPR55 heteromers.

Activation of high affinity receptor for IgE (FcεRI) by IgE/antigen complexes in mast cells (MCs) leads to the release of preformed pro-inflammatory mediators stored in granules by a Ca-dependent process known as anaphylactic degranulation. Degranulation inhibition has been proposed as a strategy to control allergies and chronic inflammation conditions. Cannabinoids are important inhibitors of inflammatory reactions but their effects on IgE/Ag-mediated MCs responses are not well described.

Tomosyn functions as a PKCδ-regulated fusion clamp in mast cell degranulation.

Soluble -ethylmaleimide-sensitive factor attachment protein receptor (SNARE) family proteins mediate membrane fusion critical for vesicular transport and cellular secretion. Mast cells rely on SNARE-mediated membrane fusion for degranulation stimulated by crosslinking of immunoglobulin E (IgE) bound to the Fcε receptor (FcεRI). We investigated the mechanisms downstream of receptor activation that control degranulation.

Fyn kinase mediates cortical actin ring depolymerization required for mast cell migration in response to TGF-β in mice.

Transforming growth factor-β (TGF-β) is a potent mast cell (MC) chemoattractant able to modulate local inflammatory reactions. The molecular mechanism leading to TGF-β-directed MC migration is not fully described. Here we analyzed the role of the Src family protein kinase Fyn on the main TGF-β-induced cytoskeletal changes leading to MC migration.