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1.
Sci Rep ; 8(1): 11276, 2018 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-30050041

RESUMO

The infusion of hypertonic saline solution (HSS) is known to be beneficial to the treatment of hypovolemic hemorrhage (HH). The central mechanism of HSS-induced cardiovascular and autonomic recovery of animals subjected to HH remains unclear. Hence, the present study evaluated the involvement of median preoptic nucleus (MnPO) and medullary noradrenergic neurons (A1 and A2) in HSS-induced cardiovascular and sympathetic responses in hemorrhagic rats. The wistar rats were subjected to specific lesion of noradrenergic neurons through the nanoinjections of anti-DßH-saporin into caudal ventrolateral medulla (A1 neurons) and nucleus of the solitary tract (A2 neurons). After recovery, mean arterial pressure (MAP) and renal sympathetic nervous activity were recorded. The HH was performed through blood withdrawal until a MAP of 60 mmHg was attained. In sham rats, HSS infusion (3M NaCl) reestablished MAP without change in HH-induced sympathoinhibition. The muscimol (agonist of GABAA receptor) was nanoinjected in MnPO during HH and MnPO inhibition abolished the recovery of MAP and HSS-induced sympathoinhibition. Simultaneous lesions of A1 and A2 abolished MAP restoration and sympathoinhibition after HSS infusion. These results suggest that the recovery of MAP and HSS-induced sympathoinhibition in hemorrhaged rats depend on intact neural projections from A1 and A2 to MnPO.


Assuntos
Adaptação Fisiológica , Neurônios Adrenérgicos/fisiologia , Fenômenos Fisiológicos Cardiovasculares , Hemorragia/fisiopatologia , Área Pré-Óptica/fisiologia , Sistema Nervoso Simpático/fisiologia , Animais , Pressão Arterial , Ratos Wistar
2.
Int J Med Mushrooms ; 19(3): 257-265, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28605341

RESUMO

Piptoporus betulinus has been used in folk medicine for millennia. However, no data currently exist regarding its potential cardiovascular activity. In this work, the crude ethanolic extract and fractions (hexane, ethyl acetate, and water) with increased polarity from the partitioning process, as well as stigmasterol (the major metabolite isolated from P. betulinus), were administered orally at different doses to normotensive male Wistar rats an hour before recording mean arterial pressure, heart rate, renal blood flow, renal vascular conductance, arterial blood flow, and arterial vascular conductance. The acute oral administration of crude ethanolic extract and all fractions did not alter mean arterial pressure when compared with the control group, which received a vehicle. In addition, subchronic (14 days) oral administration of crude ethanolic extract, fractions, and stigmasterol did not alter cardiovascular parameters. In conclusion, our findings demonstrate that oral administration of organic extracts of P. betulinus did not induce cardiovascular alterations.


Assuntos
Sistema Cardiovascular/efeitos dos fármacos , Misturas Complexas/administração & dosagem , Polyporales/química , Estigmasterol/administração & dosagem , Administração Oral , Animais , Misturas Complexas/isolamento & purificação , Masculino , Ratos Wistar , Estigmasterol/isolamento & purificação
3.
Cytokine ; 88: 184-192, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27649507

RESUMO

While the role of Toll-like receptors (TLRs) has been investigated in murine models of tegumentary leishmaniasis caused by Leishmania (Viannia) braziliensis, the interaction between TLRs and Leishmania sp. has not been investigated in human cells. The aim of this study was to evaluate the involvement of TLR4 in cytokine production of human peripheral blood mononuclear cells (PBMCs) induced by L. braziliensis, and whether the parasite alters the expression of TLR4 on monocytes/macrophages. Amastigote forms were obtained from mice lesions and PBMCs were isolated from healthy donors. PBMCs were cultured in absence or presence of IFNγ, TLR4 neutralizing antibodies, natural antagonist of TLR4 (Bartonella LPS), TLR4 agonist (E. coli LPS), and amastigote forms. The concentrations of tumor necrosis factor (TNFα) and interleukin 10 (IL-10) were assayed by ELISA and TLR4 expression by flow cytometry. Amastigotes forms of L. braziliensis induced TNFα and IL-10 production only in IFNγ-primed PBMCs. The TNFα and IL-10 production was inhibited by TLR4 neutralization, both with anti-TLR4 antibodies and Bartonella LPS. Interestingly, addition of E. coli LPS further increased TNFα but not IL-10 production induced by L. braziliensis amastigotes. Amastigotes of L. braziliensis strongly reduced membrane TLR4 expression on monocytes/macrophages, apparently by internalization after the infection. The present study reveals that TLR4 drives the production of TNFα and IL-10 induced by L. braziliensis amastigotes and that the parasites decrease TLR4 expression on monocyte surface.


Assuntos
Interleucina-10/imunologia , Leishmania braziliensis/imunologia , Macrófagos/imunologia , Monócitos/imunologia , Receptor 4 Toll-Like/imunologia , Fator de Necrose Tumoral alfa/imunologia , Adolescente , Adulto , Animais , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade
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