RESUMO
Resistance physical exercise has neuroprotective and anti-inflammatory effects on many known diseases and, therefore, it has been increasingly explored. The way in which this type of exercise exerts these actions is still under investigation. In this study, we aimed to analyze the enzymes and components of the purinergic system involved in the inflammatory process triggered by the P2X7R. Rats were divided into four groups: control, exercise (EX), lipopolysaccharide (LPS), and EX + LPS. The animals in the exercise groups were subjected to a 12-week ladder-climbing resistance physical exercise and received LPS after the last session for sepsis induction. Enzymes activities (NTPDase, 5'-nucleotidase, and adenosine deaminase), purinoceptors' density (P2X7R, A1, and A2A), and the levels of inflammatory indicators (pyrin domain-containing protein 3 (NLRP3), Caspase-1, interleukin (IL)- 6, IL-1B, and tumor necrosis factor (TNF) -α) were measured in the cortex and hippocampus of the animals. The results show that exercise prevented (in the both structures) the increase of: 1) nucleoside-triphosphatase (NTPDase) and 5'-nucleotidase activities; 2) P2X7R density; 3) NLRP3 and Caspase-1; and 4) IL-6, IL-1ß, and TNF-α It is suggested that the purinergic system and the inflammatory pathway of P2X7R are of fundamental importance and influence the effects of resistance physical exercise on LPS-induced inflammation. Thus, the modulation of the P2X7R by resistance physical exercise offers new avenues for the management of inflammatory-related illnesses.
Assuntos
Lipopolissacarídeos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Ratos , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Lipopolissacarídeos/toxicidade , 5'-Nucleotidase/metabolismo , Doenças Neuroinflamatórias , Hipocampo/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Exercício Físico , Caspases/metabolismo , Receptores Purinérgicos P2X7/metabolismoRESUMO
Pain caused by the tumor or aromatase inhibitors (AIs) is a disabling symptom in breast cancer survivors. Their mechanisms are unclear, but pro-algesic and inflammatory mediators seem to be involved. Kinins are endogenous algogenic mediators associated with various painful conditions via B1 and B2 receptor activation, including chemotherapy-induced pain and breast cancer proliferation. We investigate the involvement of the kinin B1 and B2 receptors in metastatic breast tumor (4T1 breast cancer cells)-caused pain and in aromatase inhibitors (anastrozole or letrozole) therapy-associated pain. A protocol associating the tumor and antineoplastic therapy was also performed. Kinin receptors' role was investigated via pharmacological antagonism, receptors protein expression, and kinin levels. Mechanical and cold allodynia and muscle strength were evaluated. AIs and breast tumor increased kinin receptors expression, and tumor also increased kinin levels. AIs caused mechanical allodynia and reduced the muscle strength of mice. Kinin B1 (DALBk) and B2 (Icatibant) receptor antagonists attenuated these effects and reduced breast tumor-induced mechanical and cold allodynia. AIs or paclitaxel enhanced breast tumor-induced mechanical hypersensitivity, while DALBk and Icatibant prevented this increase. Antagonists did not interfere with paclitaxel's cytotoxic action in vitro. Thus, kinin B1 or B2 receptors can be a potential target for treating the pain caused by metastatic breast tumor and their antineoplastic therapy.
Assuntos
Antineoplásicos , Dor do Câncer , Neoplasias , Camundongos , Animais , Inibidores da Aromatase/farmacologia , Inibidores da Aromatase/uso terapêutico , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Receptor B2 da Bradicinina/metabolismo , Receptor B1 da Bradicinina/metabolismo , Bradicinina/farmacologia , Dor , PaclitaxelRESUMO
Toxoplasma gondii is an obligate intracellular parasite that causes toxoplasmosis, and its congenital transmission is of paramount concern. During embryonic development, infection with the parasite causes irreversible damage to the still-forming fetus's central nervous system (CNS). In the pathogenesis of neurotoxoplasmosis, purinergic receptors prejudice neuroprotection, neuroinflammation, and activation of microbicide mechanisms against the parasitic vacuole. This study used curcumin as a treatment for neural precursor cells (NPCs) infected with T. gondii. The congenital toxoplasmosis induction consisted of maternal infection with the VEG strain, and NPCs were obtained from the telencephalon of mouse embryos. Curcumin at increasing concentrations was administered in vitro to analyze NPC metabolic activity, cell number, and size, as well as neurogliogenesis, proving to be effective in recovering the size of infected NPCs. Curcumin partially re-established impaired neurogenesis. Purinergic A1, A2A, and P2X7 receptors may be related to neuroprotection, neuroinflammatory control, and activation of mechanisms for inducing the parasite's death. ERK 1/2 was highly expressed in infected cells, while its expression rates decreased after the addition of the treatment, highlighting the possible anti-inflammatory action of curcumin. These findings suggest that curcumin treats neurological perturbations induced by toxoplasmosis.
Assuntos
Curcumina , Células-Tronco Neurais , Toxoplasma , Toxoplasmose Cerebral , Toxoplasmose Congênita , Feminino , Gravidez , Animais , Camundongos , Toxoplasma/fisiologia , Curcumina/farmacologia , Toxoplasmose Congênita/parasitologiaRESUMO
ATP and adenosine exert pivotal roles in the development, maintenance, and metastatic spreading of melanoma. The action of such key melanoma tumor microenvironment (TME) constituents might be complementary or opposed, and their effects are not exclusive to immune cells but also to other host cells and tumor cells. The effects of ATP are controlled by the axis CD39/73, resulting in adenosine, the main actor in the TME, and A2A is the crucial mediator of its effects. We evaluated ATP and adenosine signaling through A2A on B16F10 melanoma cells using istradefylline (IST) (antiparkinsonian A2A antagonist) and caffeine (CAF) treatments after exposure to ATP and adenosine. Adenosine increased melanoma cell viability and proliferation in a concentration-dependent manner. ATP increases viability only as a substrate by CD39 to produce adenosine. Both IST and CAF are toxic to B16F10 cells, but only IST potentialized paclitaxel-induced cytotoxic effects, even decreasing its IC50 value. IST positively modulated CD39 and CD73 expression. CD39 activity was increased, and E-ADA was reduced, indicating that the melanoma cells promoted compensatory feedback in the production and maintenance of adenosine levels. A2A antagonism by IST reduced the factors associated with malignancy, like migration, adhesion, colony formation, and the capacity to produce melanin. Moreover, IST significantly increases nitric oxide (NO) production, which correlates to a decline in melanoma cell viability by apoptotic events. Altogether, our results suggest that adenosine signaling through A2A is essential for B16F10 cells, and its inhibition by IST causes compensatory purinergic enzymatic modulations. Furthermore, IST is a promising therapy that provides new ways to improve current melanoma treatments.
RESUMO
BACKGROUND: Melanoma is the most lethal form of skin cancer, and its incidence has increased considerably in the last decades. Melanoma presents difficult treatment with strong resistance of tumor cells, due to its extremely invasive nature with high capacity to metastases. Berberine (BBR), an isoquinoline alkaloid, is a molecule found in several medicinal plants, and has been studied in several diseases, demonstrating antimicrobial, antidiabetic and anti-inflammatory properties and anti-tumorigenic effects. METHODS AND RESULTS: In SK-MEL-28 cells, 50 µM BBR treatment for 24 h decreased cell viability by 50 percent. This concentration generated cell death both by early apoptosis and necrosis, with an increase in the DNA damage index. BBR increased (*p < 0.05) the proportion of cells in G1/G0 phase and decreased (###p < 0.005) the percentage of cells in S phase. The alcaloid increased (****p < 0.001) ROS production compared to untreated controls with an increase in activated caspase 3 and phosphorylated p53 protein levels. In addition, BBR significantly enhanced ERK as well as both pro- and anti-inflammatory cytokine expression compared to untreated controls. CONCLUSIONS: BBR has important antiproliferative effects and may be alone or in adjunct therapy a promising candidate for melanoma treatment, a cancer with great incidence and high lethality.
Assuntos
Berberina , Melanoma , Apoptose , Berberina/farmacologia , Linhagem Celular Tumoral , Citocinas/metabolismo , Humanos , Melanoma/tratamento farmacológicoRESUMO
Aluminum (Al) is ubiquitously present in the environment and known to be a neurotoxin for humans. The trivalent free Al anion (Al3+) can cross the blood-brain barrier (BBB), accumulate in the brain, and elicit harmful effects to the central nervous system (CNS) cells. Thus, evidence has suggested that Al increases the risk of developing neurodegenerative diseases, particularly Alzheimer's disease (AD). Purinergic signaling has been shown to play a role in several neurological conditions as it can modulate the functioning of several cell types, such as microglial cells, the main resident immune cells of the CNS. However, Al effects on microglial cells and the role of the purinergic system remain elusive. Based on this background, this study is aimed at assessing the modulation of Al on purinergic system parameters of microglial cells. An in vitro study was performed using brain microglial cells exposed to Al chloride (AlCl3) and lipopolysaccharide (LPS) for 96 h. The uptake of Al, metabolism of nucleotides (ATP, ADP, and AMP) and nucleoside (adenosine), and the gene expression and protein density of purinoceptors were investigated. The results showed that both Al and LPS increased the breakdown of adenosine, whereas they decreased nucleotide hydrolysis. Furthermore, the findings revealed that both Al and LPS triggered an increase in gene expression and protein density of P2X7R and A2AR receptors, whereas reduced the A1R receptor expression and density. Taken together, the results showed that Al and LPS altered the setup of the purinergic system of microglial cells. Thus, this study provides new insights into the involvement of the purinergic system in the mechanisms underlying Al toxicity in microglial cells.
Assuntos
Alumínio/efeitos adversos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Receptores Purinérgicos/metabolismo , Animais , Biomarcadores , Encéfalo/efeitos dos fármacos , Encéfalo/imunologia , Encéfalo/metabolismo , Linhagem Celular , Células Cultivadas , Imunofluorescência , Expressão Gênica , Humanos , Lipopolissacarídeos/imunologia , Camundongos , Microglia/imunologia , Receptores Purinérgicos/genéticaRESUMO
Neuroinflammation is a predisposing factor for the development of cognitive impairment and dementia. Among the new molecules that are currently being studied, ellagic acid (EA) has stood out for its neuroprotective properties. The present study investigated the effects of ellagic acid in the object recognition test, oxidative stress, cholinergic neurotransmission, glial cell expression, and phosphorylated Tau protein expression. For this, 32 male Wistar rats received an intraperitoneal (IP) application of lipopolysaccharides (LPS) at a dose of 250 µg/kg or 0.9% saline solution (SAL) for 8 days. Two hours after the IP injections, the animals received 100 mg/kg of EA or SAL via intragastric gavage. Behavioral parameters (open field test and object recognition) were performed on days 5, 6, and 7 of the experimental periods. The results showed that the treatment with EA in the LPS group was able to inhibit cognitive impairment, modulate the immune system response by significantly reducing glial cell expression, attenuating phosphorylated Tau and oxidative damage with consequent improvement in the antioxidant system, as well as preventing the increase of acetylcholinesterase activity. Thus, the neuroprotective effects of EA and its therapeutic potential in cognitive disorders secondary to neuroinflammation were demonstrated.
Assuntos
Disfunção Cognitiva/tratamento farmacológico , Ácido Elágico/uso terapêutico , Inflamação/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Acetilcolinesterase/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Disfunção Cognitiva/induzido quimicamente , Hipocampo/efeitos dos fármacos , Inflamação/induzido quimicamente , Lipopolissacarídeos , Masculino , Teste de Campo Aberto/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ratos Wistar , Proteínas tau/química , Proteínas tau/metabolismoRESUMO
Glioblastoma multiforme (GM) is the most prevalent tumor among gliomas and presents the highest mortality rate among brain tumors. Berberine (BBR) is an alkaloid isoquinoline found in medicinal plants such as Coptis chinensis. Studies have been showed that BBR presents protective activity in mesenchymal cells and neurons, and antitumor properties in breast cancer and hepatocarcinoma. The aim of this study was to investigate the antitumor effects of BBR in GM U87MG cells, as well as to identify, whether such effects are mediated by oxidative stress and canonical apoptotic pathways. After treatment with several concentrations of BBR (10, 25, 100 and 250 µM) for 24, 48 and 72 h of exposure, BBR reduce cell viability of U87MG cells in a concentration- and time-dependent manner. Afterwards, it was observed that BBR, starting at a concentration of 25 µM of 24 h exposure, significantly suppressed proliferation and increased early apoptosis (53.5% ± 11.15 of annexin V+ propidium iodide- cells) compared to untreated cells (7.5% ± 4.6). BBR-induced apoptosis was independent from AMPK activity and did not change total caspase-3 and p-p53 levels. Moreover, BBR (25 µM/24 h) increased oxidative stress in U87MG cells, evidenced by high levels of reactive oxygen species, thiobarbituric acid reactive substance and protein carbonylation. Considering the antitumor effects of BBR in U87MG cells, this compound may be a potential candidate for adjuvant GM treatment.
Assuntos
Apoptose/efeitos dos fármacos , Berberina/farmacologia , Glioblastoma/metabolismo , Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Berberina/metabolismo , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Glioblastoma/fisiopatologia , Humanos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
The role of caffeinated beverages on efficiency of acute inflammatory responses is not yet fully understood. This study analyzed the effect of five hot water extracts, coffee (CO), black/green tea (BT/GT), yerba mate (YM), and guarana (GU) on inflammatory modulation of non-activated human peripheral blood mononuclear cells (PBMCs), yeast-activated human neutrophils, and granulocytic coelomocytes from Eisenia fetida earthworm. Based on preliminary tests, a concentration of 10⯵g/mL was chosen for subsequent assays, as at this concentration, the extracts exhibited antioxidant, genoprotective, and non-cytotoxic properties. Immunoassays using 24-h PBMC supernatant showed that all extracts decreased levels of pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α, and IFN-γ), and increased levels of the anti-inflammatory cytokine, IL-10. Further, these extracts induced overexpression of cytokine genes in 24-h cultures. These results suggest that an increase in the levels of mRNAs and/or inactive cytokines in the cytoplasm improves the "immune cytokine response. Analysis of the yeast encapsulation processes, and production of human neutrophils and coelomocyte extracellular DNA traps suggests that extracts also improve the immune response in humans and earthworms. However, for E. fetida, the intensity of these results varied from extract. Overall, our results suggest that caffeinated beverages may improve an organism's efficiency against acute inflammatory processes.
Assuntos
Bebidas , Cafeína/farmacologia , Inflamação/prevenção & controle , Leucócitos Mononucleares/efeitos dos fármacos , Animais , Citocinas/imunologia , Humanos , Mediadores da Inflamação/imunologia , Leucócitos Mononucleares/imunologia , OligoquetosRESUMO
Cutaneous melanoma (CM) is an extremely aggressive cancer presenting low survival and high mortality. The vast majority of patients affected by this disease does not respond or show resistance to the chemotherapeutic drugs, which makes the treatment ineffective. In this sense, the necessity for the development of new agents to assist in CM therapy is extremely important. One of the sources of great interest in this search are compounds of natural origin. Among these compounds, caffeic acid has demonstrated a broad spectrum of pharmacological activities as well as antitumor effects in some types of cancer. Therefore, the objective of this work was to investigate the possible antitumor effect of caffeic acid on the SK-Mel-28 cell line, human CM cells. Cells were cultured in flasks with culture medium containing fetal bovine serum, antibiotic, and antifungal, and maintained in ideal conditions. Cells were treated with 25 µM, 50 µM, 100 µM, 150 µM and 200 µM of caffeic acid and dacarbazine at 1 mg/mL. We verified the effect on cell viability and cell death, apoptosis, cell cycle, colony formation and gene expression of caspases. Results showed a decrease in cell viability, cell death induction by apoptosis, inhibition of colony formation, modulation of cell cycle and alterations in gene expression of caspases after caffeic acid treatment. These results suggest an antitumor effect of the compound on SK-Mel-28 cells. This study provides original information on mechanisms by which caffeic acid may play a key role in preventing tumor progression in human melanoma cells.