RESUMO
Although SARS-CoV-2 induces mucin hypersecretion in the respiratory tract, hyposalivation/xerostomia has been reported by COVID-19 patients. We evaluate the submandibular gland (SMGs) pathogenesis in SARS-CoV-2-infected K18-hACE2 mice, focusing on the impact of infection on the mucin production and structural integrity of acini, ductal system, myoepithelial cells (MECs) and telocytes. The spike protein, the nucleocapsid protein, hACE2, actin, EGF, TNF-α and IL-1ß were detected by immunofluorescence, and the Egfr and Muc5b expression was evaluated. In the infected animals, significant acinar hypertrophy was observed in contrast to ductal atrophy. Nucleocapsid proteins and/or viral particles were detected in the SMG cells, mainly in the nuclear membrane-derived vesicles, confirming the nuclear role in the viral formation. The acinar cells showed intense TNF-α and IL-1ß immunoexpression, and the EGF-EGFR signaling increased, together with Muc5b upregulation. This finding explains mucin hypersecretion and acinar hypertrophy, which compress the ducts. Dying MECs and actin reduction were also observed, indicating failure of contraction and acinar support, favoring acinar hypertrophy. Viral assembly was found in the dying telocytes, pointing to these intercommunicating cells as viral transmitters in SMGs. Therefore, EGF-EGFR-induced mucin hypersecretion was triggered by SARS-CoV-2 in acinar cells, likely mediated by cytokines. The damage to telocytes and MECs may have favored the acinar hypertrophy, leading to ductal obstruction, explaining xerostomia in COVID-19 patients. Thus, acinar cells, telocytes and MECs may be viral targets, which favor replication and cell-to-cell viral transmission in the SMG, corroborating the high viral load in saliva of infected individuals.
Assuntos
COVID-19 , Receptores ErbB , SARS-CoV-2 , Glândula Submandibular , Xerostomia , COVID-19/patologia , COVID-19/virologia , COVID-19/metabolismo , Animais , Glândula Submandibular/virologia , Glândula Submandibular/patologia , Glândula Submandibular/metabolismo , SARS-CoV-2/fisiologia , Camundongos , Xerostomia/etiologia , Xerostomia/patologia , Xerostomia/virologia , Xerostomia/metabolismo , Receptores ErbB/metabolismo , Humanos , Enzima de Conversão de Angiotensina 2/metabolismo , Mucina-5B/metabolismo , Células Acinares/patologia , Células Acinares/metabolismo , Células Acinares/virologia , Interleucina-1beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Modelos Animais de DoençasRESUMO
AIMS: To investigate the SARS-CoV-2 Spike protein (Spk)-induced inflammatory response and its downmodulation by diminazene aceturate (DIZE). MATERIALS AND METHODS: Through inducing Spk inflammation in murine models, leukocyte migration to the peritoneum, levels of myeloperoxidase (MPO), malondialdehyde (MDA), rolling and adhesion of mesenteric leukocytes, and vascular permeability were investigated. Extracellular DNA traps (DETs) induced by Spk and the production of IL-6 and TNF-α were analyzed using human neutrophils, monocytes, and macrophages. In silico assays assessed the molecular interaction between DIZE and molecules related to leukocyte migration and DETs induction. KEY FINDINGS: Spk triggered acute inflammation, demonstrated by increasing leukocyte migration. Oxidative stress was evidenced by elevated levels of MPO and MDA in the peritoneal liquid. DIZE attenuated cell migration, rolling, and leukocyte adhesion, improved vascular barrier function, mitigated DETs, and reduced the production of Spk-induced pro-inflammatory cytokines. Computational studies supported our findings, showing the molecular interaction of DIZE with targets such as ß2 integrin, PI3K, and PAD2 due to its intermolecular coupling. SIGNIFICANCE: Our results outline a novel role of DIZE as a potential therapeutic agent for mitigating Spk-induced inflammation.
Assuntos
COVID-19 , Movimento Celular , Diminazena , Armadilhas Extracelulares , Inflamação , Leucócitos , SARS-CoV-2 , Diminazena/farmacologia , Diminazena/análogos & derivados , Animais , Camundongos , Humanos , Movimento Celular/efeitos dos fármacos , Armadilhas Extracelulares/metabolismo , Armadilhas Extracelulares/efeitos dos fármacos , Leucócitos/metabolismo , Leucócitos/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , Inflamação/metabolismo , Inflamação/tratamento farmacológico , COVID-19/metabolismo , Masculino , Tratamento Farmacológico da COVID-19 , Adesão Celular/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Glicoproteína da Espícula de CoronavírusRESUMO
In this study, we investigated whether severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) spike protein may modify angiotensin-converting enzyme 2 (ACE2) activity in the plasma, heart, kidney, liver, lung, and six brain regions (amygdala, brain stem, cortex, hippocampus, hypothalamus, and striatum) of diabetic and hypertensive rats. We determine ACE2 activity in the plasma and lysates of heart, kidney, liver, lung, and six brain regions. MLN-4760 inhibits ACE2 activity in the plasma and all organs. On the other hand, soluble ACE2 (sACE2) activity increased in the plasma of diabetic rats, and there was no change in the plasma of hypertensive rats. ACE2 activity was augmented in the liver, brain stem, and striatum, while it decreased in the kidney, amygdala, cortex, and hippocampus of diabetic rats. ACE2 activity increased in the kidney, liver, and lung, while it decreased in the heart, amygdala, cortex, and hypothalamus of hypertensive rats. We measured the ACE2 content via enzyme-linked immunosorbent assay and found that ACE2 protein levels increased in the heart, while it decreased in the plasma, kidney, brain stem, cortex, hippocampus, hypothalamus, and striatum of diabetic rats. ACE2 protein levels decreased in the brain stem, cortex, hippocampus, and hypothalamus of hypertensive rats. Our data showed that the spike protein enhanced ACE2 activity in the liver and lungs of diabetic rats, as well as in the heart and three of the brain regions (cortex, hypothalamus, and striatum) of hypertensive rats.
Assuntos
Enzima de Conversão de Angiotensina 2 , Hipertensão , Glicoproteína da Espícula de Coronavírus , Animais , Enzima de Conversão de Angiotensina 2/metabolismo , Ratos , Glicoproteína da Espícula de Coronavírus/metabolismo , Masculino , Hipertensão/metabolismo , SARS-CoV-2 , Diabetes Mellitus Experimental/metabolismo , Encéfalo/metabolismo , Encéfalo/enzimologia , COVID-19/metabolismo , COVID-19/virologia , Carboxipeptidases/metabolismo , Rim/metabolismo , Rim/enzimologia , Humanos , Imidazóis , Leucina/análogos & derivadosRESUMO
Calcium is a secondary messenger that interacts with several cellular proteins, regulates various physiological processes, and plays a role in diseases such as viral infections. Next-generation probiotics and live biotherapeutic products are linked to the regulation of intracellular calcium levels. Some viruses can manipulate calcium channels, pumps, and membrane receptors to alter calcium influx and promote virion production and release. In this study, we examined the use of bacteria for the prevention and treatment of viral diseases, such as coronavirus of 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Vaccination programs have helped reduce disease severity; however, there is still a lack of well-recognized drug regimens for the clinical management of COVID-19. SARS-CoV-2 interacts with the host cell calcium (Ca2+), manipulates proteins, and disrupts Ca2+ homeostasis. This article explores how viruses exploit, create, or exacerbate calcium imbalances, and the potential role of probiotics in mitigating viral infections by modulating calcium signaling. Pharmacological strategies have been developed to prevent viral replication and block the calcium channels that serve as viral receptors. Alternatively, probiotics may interact with cellular calcium influx, such as Lactobacillus spp. The interaction between Akkermansia muciniphila and cellular calcium homeostasis is evident. A scientific basis for using probiotics to manipulate calcium channel activity needs to be established for the treatment and prevention of viral diseases while maintaining calcium homeostasis. In this review article, we discuss how intracellular calcium signaling can affect viral replication and explore the potential therapeutic benefits of probiotics.
Assuntos
COVID-19 , Cálcio , Probióticos , SARS-CoV-2 , Probióticos/uso terapêutico , Probióticos/farmacologia , Humanos , COVID-19/metabolismo , COVID-19/virologia , Cálcio/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Tratamento Farmacológico da COVID-19RESUMO
COVID-19, caused by SARS-CoV-2, affects neuronal cells, causing several symptoms such as memory loss, anosmia and brain inflammation. Curcuminoids (Me08 e Me23) and curcumin (CUR) are derived from Curcuma Longa extract (EXT). Many therapeutic actions have been linked to these compounds, including antiviral action. Given the severe implications of COVID-19, especially within the central nervous system, our study aims to shed light on the therapeutic potential of curcuminoids against SARS-CoV-2 infection, particularly in neuronal cells. Here, we investigated the effects of CUR, EXT, Me08 and Me23 in human neuroblastoma SH-SY5Y. We observed that Me23 significantly decreased the expression of plasma membrane-associated transmembrane protease serine 2 (TMPRSS2) and TMPRSS11D, consequently mitigating the elevated ROS levels induced by SARS-CoV-2. Furthermore, Me23 exhibited antioxidative properties by increasing NRF2 gene expression and restoring NQO1 activity following SARS-CoV-2 infection. Both Me08 and Me23 effectively reduced SARS-CoV-2 replication in SH-SY5Y cells overexpressing ACE2 (SH-ACE2). Additionally, all of these compounds demonstrated the ability to decrease proinflammatory cytokines such as IL-6, TNF-α, and IL-17, while Me08 specifically reduced INF-γ levels. Our findings suggest that curcuminoid Me23 could serve as a potential agent for mitigating the impact of COVID-19, particularly within the context of central nervous system involvement.
Assuntos
Anti-Inflamatórios , Antioxidantes , Antivirais , Tratamento Farmacológico da COVID-19 , Curcumina , SARS-CoV-2 , Humanos , Curcumina/farmacologia , Curcumina/análogos & derivados , Antioxidantes/farmacologia , Antivirais/farmacologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/fisiologia , Anti-Inflamatórios/farmacologia , Linhagem Celular Tumoral , Curcuma/química , Serina Endopeptidases/metabolismo , COVID-19/virologia , COVID-19/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Extratos Vegetais/farmacologia , Citocinas/metabolismo , NAD(P)H Desidrogenase (Quinona)/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/virologiaRESUMO
Tubular proteinuria is a common feature in COVID-19 patients, even in the absence of established acute kidney injury. SARS-CoV-2 spike protein (S protein) was shown to inhibit megalin-mediated albumin endocytosis in proximal tubule epithelial cells (PTECs). Angiotensin-converting enzyme type 2 (ACE2) was not directly involved. Since Toll-like receptor 4 (TLR4) mediates S protein effects in various cell types, we hypothesized that TLR4 could be participating in the inhibition of PTECs albumin endocytosis elicited by S protein. Two different models of PTECs were used: porcine proximal tubule cells (LLC-PK1) and human embryonic kidney cells (HEK-293). S protein reduced Akt activity by specifically inhibiting of threonine 308 (Thr308) phosphorylation, a process mediated by phosphoinositide-dependent kinase 1 (PDK1). GSK2334470, a PDK1 inhibitor, decreased albumin endocytosis and megalin expression mimicking S protein effect. S protein did not change total TLR4 expression but decreased its surface expression. LPS-RS, a TLR4 antagonist, also counteracted the effects of the S protein on Akt phosphorylation at Thr308, albumin endocytosis, and megalin expression. Conversely, these effects of the S protein were replicated by LPS, an agonist of TLR4. Incubation of PTECs with a pseudovirus containing S protein inhibited albumin endocytosis. Null or VSV-G pseudovirus, used as control, had no effect. LPS-RS prevented the inhibitory impact of pseudovirus containing the S protein on albumin endocytosis but had no influence on virus internalization. Our findings demonstrate that the inhibitory effect of the S protein on albumin endocytosis in PTECs is mediated through TLR4, resulting from a reduction in megalin expression.
Assuntos
Endocitose , Túbulos Renais Proximais , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Receptor 4 Toll-Like , Receptor 4 Toll-Like/metabolismo , Endocitose/efeitos dos fármacos , Humanos , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/virologia , Animais , Glicoproteína da Espícula de Coronavírus/metabolismo , SARS-CoV-2/metabolismo , Células HEK293 , Suínos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosforilação , COVID-19/metabolismo , COVID-19/virologia , COVID-19/patologia , Albuminas/metabolismo , Células LLC-PK1 , Células Epiteliais/metabolismo , Células Epiteliais/virologiaRESUMO
Severe cases of COVID-19 are characterized by development of acute respiratory distress syndrome (ARDS). Water accumulation in the lungs is thought to occur as consequence of an exaggerated inflammatory response. A possible mechanism could involve decreased activity of the epithelial Na+ channel, ENaC, expressed in type II pneumocytes. Reduced transepithelial Na+ reabsorption could contribute to lung edema due to reduced alveolar fluid clearance. This hypothesis is based on the observation of the presence of a novel furin cleavage site in the S protein of SARS-CoV-2 that is identical to the furin cleavage site present in the alpha subunit of ENaC. Proteolytic processing of αENaC by furin-like proteases is essential for channel activity. Thus, competition between S protein and αENaC for furin-mediated cleavage in SARS-CoV-2-infected cells may negatively affect channel activity. Here we present experimental evidence showing that coexpression of the S protein with ENaC in a cellular model reduces channel activity. In addition, we show that bidirectional competition for cleavage by furin-like proteases occurs between ãENaC and S protein. In transgenic mice sensitive to lethal SARS-CoV-2, however, a significant decrease in gamma ENaC expression was not observed by immunostaining of lungs infected as shown by SARS-CoV2 nucleoprotein staining.
Assuntos
COVID-19 , Canais Epiteliais de Sódio , Furina , Camundongos Transgênicos , Proteólise , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Canais Epiteliais de Sódio/metabolismo , Animais , Humanos , Camundongos , Furina/metabolismo , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/metabolismo , COVID-19/metabolismo , COVID-19/virologia , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/virologia , Pulmão/metabolismo , Pulmão/virologia , Pulmão/patologia , Células HEK293RESUMO
We investigated the effects of obesity on metabolic, inflammatory, and oxidative stress parameters in the adipose tissue of patients with fatal COVID-19. Postmortem biopsies of subcutaneous adipose tissue were obtained from 25 unvaccinated inpatients who passed from COVID-19, stratified as nonobese (N-OB; body mass index [BMI], 26.5 ± 2.3 kg m-2) or obese (OB BMI 34.2 ± 5.1 kg m-2). Univariate and multivariate analyses revealed that body composition was responsible for most of the variations detected in the metabolome, with greater dispersion observed in the OB group. Fifteen metabolites were major segregation factors. Results from the OB group showed higher levels of creatinine, myo-inositol, O-acetylcholine, and succinate, and lower levels of sarcosine. The N-OB group showed lower levels of glutathione peroxidase activity, as well as higher content of IL-6 and adiponectin. We revealed significant changes in the metabolomic profile of the adipose tissue in fatal COVID-19 cases, with high adiposity playing a key role in these observed variations. These findings highlight the potential involvement of metabolic and inflammatory pathways, possibly dependent on hypoxia, shedding light on the impact of obesity on disease pathogenesis and suggesting avenues for further research and possible therapeutic targets.
Assuntos
Autopsia , COVID-19 , Metaboloma , Obesidade , Humanos , COVID-19/metabolismo , COVID-19/mortalidade , COVID-19/patologia , COVID-19/virologia , Obesidade/metabolismo , Obesidade/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , SARS-CoV-2/metabolismo , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Metabolômica/métodos , Índice de Massa Corporal , Adulto , Estresse Oxidativo , Interleucina-6/metabolismoRESUMO
Type II pneumocytes are the target of the SARS-CoV-2 virus, which alters their redox homeostasis to increase reactive oxygen species (ROS). Melatonin (MT) has antioxidant proprieties and protects mitochondrial function. In this study, we evaluated whether treatment with MT compensated for the redox homeostasis alteration in serum from COVID-19 patients. We determined oxidative stress (OS) markers such as carbonyls, glutathione (GSH), total antioxidant capacity (TAC), thiols, nitrites (NO2-), lipid peroxidation (LPO), and thiol groups in serum. We also studied the enzymatic activities of glutathione peroxidase (GPx), glutathione-S-transferase (GST), reductase (GR), thioredoxin reductase (TrxR), extracellular superoxide dismutase (ecSOD) and peroxidases. There were significant increases in LPO and carbonyl quantities (p ≤ 0.03) and decreases in TAC and the quantities of NO2-, thiols, and GSH (p < 0.001) in COVID-19 patients. The activities of the antioxidant enzymes such as ecSOD, TrxR, GPx, GST, GR, and peroxidases were decreased (p ≤ 0.04) after the MT treatment. The treatment with MT favored the activity of the antioxidant enzymes that contributed to an increase in TAC and restored the lost redox homeostasis. MT also modulated glucose homeostasis, functioning as a glycolytic agent, and inhibited the Warburg effect. Thus, MT restores the redox homeostasis that is altered in COVID-19 patients and can be used as adjuvant therapy in SARS-CoV-2 infection.
Assuntos
Antioxidantes , Tratamento Farmacológico da COVID-19 , COVID-19 , Homeostase , Melatonina , Oxirredução , Estresse Oxidativo , SARS-CoV-2 , Melatonina/uso terapêutico , Melatonina/farmacologia , Humanos , Oxirredução/efeitos dos fármacos , COVID-19/metabolismo , COVID-19/virologia , COVID-19/sangue , Homeostase/efeitos dos fármacos , Antioxidantes/metabolismo , Antioxidantes/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Masculino , Feminino , Pessoa de Meia-Idade , SARS-CoV-2/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Idoso , Adulto , Espécies Reativas de Oxigênio/metabolismo , Glutationa/metabolismo , Glutationa/sangueRESUMO
The Coronavirus Disease 2019 (COVID-19) pandemic has resulted in the loss of millions of lives, although a majority of those infected have managed to survive. Consequently, a set of outcomes, identified as long COVID, is now emerging. While the primary target of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the respiratory system, the impact of COVID-19 extends to various body parts, including the bone. This study aims to investigate the effects of acute SARS-CoV-2 infection on osteoclastogenesis, utilizing both ancestral and Omicron viral strains. Monocyte-derived macrophages, which serve as precursors to osteoclasts, were exposed to both viral variants. However, the infection proved abortive, even though ACE2 receptor expression increased postinfection, with no significant impact on cellular viability and redox balance. Both SARS-CoV-2 strains heightened osteoclast formation in a dose-dependent manner, as well as CD51/61 expression and bone resorptive ability. Notably, SARS-CoV-2 induced early pro-inflammatory M1 macrophage polarization, shifting toward an M2-like profile. Osteoclastogenesis-related genes (RANK, NFATc1, DC-STAMP, MMP9) were upregulated, and surprisingly, SARS-CoV-2 variants promoted RANKL-independent osteoclast formation. This thorough investigation illuminates the intricate interplay between SARS-CoV-2 and osteoclast precursors, suggesting potential implications for bone homeostasis and opening new avenues for therapeutic exploration in COVID-19.