RESUMO
Infection by SARS-CoV-2 is associated with uncontrolled inflammatory response during COVID-19 severe disease, in which monocytes are one of the main sources of pro-inflammatory mediators leading to acute respiratory distress syndrome. Extracellular vesicles (EVs) from different cells play important roles during SARS-CoV-2 infection, but investigations describing the involvement of EVs from primary human monocyte-derived macrophages (MDM) on the regulation of this infection are not available. Here, we describe the effects of EVs released by MDM stimulated with the neuropeptides VIP and PACAP on SARS-CoV-2-infected monocytes. MDM-derived EVs were isolated by differential centrifugation of medium collected from cells cultured for 24 h in serum-reduced conditions. Based on morphological properties, we distinguished two subpopulations of MDM-EVs, namely large (LEV) and small EVs (SEV). We found that MDM-derived EVs stimulated with the neuropeptides inhibited SARS-CoV-2 RNA synthesis/replication in monocytes, protected these cells from virus-induced cytopathic effects and reduced the production of pro-inflammatory mediators. In addition, EVs derived from VIP- and PACAP-treated MDM prevented the SARS-CoV-2-induced NF-κB activation. Overall, our findings suggest that MDM-EVs are endowed with immunoregulatory properties that might contribute to the antiviral and anti-inflammatory responses in SARS-CoV-2-infected monocytes and expand our knowledge of EV effects during COVID-19 pathogenesis.
RESUMO
The nano-sized membrane enclosed extracellular vesicles (EVs) released by virtually all cell types play an essential role in intercellular communication via delivering bio-molecules, such as nucleic acids, proteins, lipids, and other molecules to recipient cells. By mediating an active and steady-state cell-to-cell communication, EVs contribute to regulating and preserving cellular homeostasis. On the other hand, EVs can also spread pathogen-derived molecules during infections, subverting the host immune responses during infections and thus worsening pathophysiological processes. In recent years, the biological functioning of EVs has become a widespread research field in basic and clinical branches of medical sciences due to their potential role in therapeutic applications for several diseases. This review aims to summarize the main recent findings regarding the implication of EVs shed by human macrophages (MΦ-EVs) and how they can modulate the host immune response to control or increase the damage caused by infectious agents. We will also present the methods used to describe MΦ-EVs, as well as the potential of these EVs as disease diagnostic tools for some human pathogens. We believe that an in-depth understanding of the host-pathogen interactions mediated by MΦ-EVs may trigger the development of innovative therapeutic strategies against infectious diseases.
Assuntos
Vesículas Extracelulares/fisiologia , Interações Hospedeiro-Patógeno/fisiologia , Macrófagos/fisiologia , Comunicação Celular/fisiologia , Doenças Transmissíveis/patologia , Doenças Transmissíveis/fisiopatologia , HumanosRESUMO
Extracellular vesicles (EVs) are small membrane-limited structures derived from outward budding of the plasma membrane or endosomal system that participate in cellular communication processes through the transport of bioactive molecules to recipient cells. To date, there are no published methodological works showing step-by-step the isolation, characterization and internalization of small EVs secreted by human primary macrophages derived from circulating monocytes (MDM-derived sEVs). Thus, here we aimed to provide an alternative protocol based on differential ultracentrifugation (dUC) to describe small EVs (sEVs) from these cells. Monocyte-derived macrophages were cultured in EV-free medium during 24, 48 or 72 h and, then, EVs were isolated from culture supernatants by (dUC). Macrophages secreted a large amount of sEVs in the first 24 h, with size ranging from 40-150 nm, peaking at 105 nm, as evaluated by nanoparticle tracking analysis and scanning electron microscopy. The markers Alix, CD63 and CD81 were detected by immunoblotting in EV samples, and the co-localization of CD63 and CD81 after sucrose density gradient ultracentrifugation (S-DGUC) indicated the presence of sEVs from late endosomal origin. Confocal fluorescence revealed that the sEVs were internalized by primary macrophages after three hours of co-culture. The methodology here applied aims to contribute for enhancing reproducibility between the limited number of available protocols for the isolation and characterization of MDM-derived sEVs, thus providing basic knowledge in the area of EV methods that can be useful for those investigators working with sEVs released by human primary macrophages derived from circulating monocytes.
Assuntos
Comunicação Celular , Vesículas Extracelulares/metabolismo , Macrófagos/metabolismo , Buffy Coat/citologia , Diferenciação Celular , Fracionamento Celular/métodos , Centrifugação com Gradiente de Concentração/métodos , Técnicas de Cocultura , Voluntários Saudáveis , Humanos , Microscopia Intravital , Macrófagos/citologia , Macrófagos/ultraestrutura , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Monócitos/fisiologia , Cultura Primária de CélulasRESUMO
In this work, the degradation of sulfamethazine (SMT), sulfadiazine (SMD), and sulfamethoxazole (SMX) by using UV light, UV/H2O2, and UV/S2O8-2 was analyzed. Direct photolysis was studied by varying the lamp power and the solution pH. DFT calculations were carried out to corroborate the efficiency of the degradation as a function of the solution pH. The variation of the apparent rate constant, kap, was determined in the indirect photolysis by employing an experimental Box-Behnken-type response surface design. The results evidenced that SMX can be efficiently degraded by applying UV radiation independent of the operating conditions. Nevertheless, the quantum yields for SMT and SMD were close to zero, indicating a low energy efficiency for their photochemical transformation. The effect of the solution pH showed that the photodegradation of sulfonamides depends both on the amount of radiation absorbed as the electronic density. Calculations based on density functional theory and supported by the quantum theory of atoms in molecules allowed to describe fragmentation patterns in the systems under study, proving the lability of S14-C2, N17-C18, and N22-O22 bonds, for SMT, SMD, and SMX, respectively. From response surface methodology, four statistically reliable equations were obtained to determine the kap value as a function of the system operating conditions. Finally, SO4â¢- radicals proved to have a higher reactivity to degrade SMT and SMD compared with HO⢠radicals regardless of the operating conditions of the system.
Assuntos
Sulfametoxazol , Poluentes Químicos da Água , Teoria da Densidade Funcional , Peróxido de Hidrogênio , Cinética , Oxirredução , Fotólise , Sulfadiazina , Sulfametazina , Raios UltravioletaRESUMO
Hemangiomas are benign vascular tumors, whose origin comes from the embryonic mesodermal tissue remains. The liver is the most common location. Its location in the teres ligament is extremely rare. This is a 59 years old male admitted because of episodes of epigastric pain for six months. A CT scan and MRI demostrated a 2 cm diameter lesion located near the Teres ligament. Laparoscopic resection was performed. Hemangiomas are the most common benign solid tumors located in the liver. They represents 73% of all benign liver tumors. MRI is the imaging of greater certainty for diagnosis. The Teres ligament (ligamentum teres hepatis) is a fibrous cord resulting in obliteration of the umbilical vein. The location of hemangiomas in this region is extremely rare but should be considered and should make the differential diagnosis with a pedicled hepatic hemangioma or gastointestinal stromal tumors.
Assuntos
Hemangioma/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Ligamento Redondo do Fígado/diagnóstico por imagem , Hemangioma/cirurgia , Humanos , Neoplasias Hepáticas/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Ligamento Redondo do Fígado/cirurgia , Tomografia Computadorizada por Raios XRESUMO
INTRODUCTION: Obesity today is a major health problem worldwide and the leading health problem in Western countries because it is associated with multiple comorbidities that increase the mortality of these patients. MATERIAL AND METHODS: A review of the literature was done in PubMed (Medline) and Cochrane Library of randomized controlled trials comparing gastric bypass with sleeve gastrectomy in the treatment of obesity and type 2 diabetes mellitus (T2DM). Eighteen papers were found, of which eleven met the initial inclusion criteria. DISCUSSION: The variables analyzed to determine the superiority of one technique over the other were: the percentage ofexcess BMI lost (% EIMCP), the percentage of excess weight loss (% EPP), BMI at the end of the study, lost Kg and the percentage of weight lost. Regarding the control of T2DM fasting glycemia, the glycosylated hemoglobin (HbAlc), whether or not oral agents or insulin were considered. CONCLUSION: No highlighting differences in results that can be obtained with RYGB and MG to control obesity and T2DM. Either method achieves excellent results, even surpassing those obtained with dietary, pharmacological and behavioral treatment.