Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
Explore (NY) ; 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37926604

RESUMO

INTRODUCTION: A revision of several experimental results on cells shows that electromagnetic radiation, either produced by biofield therapy (BFT) or laser, induced an increase in intracellular free calcium concentration. An explanation of this phenomenon is proposed. METHODS: Quantum chemistry calculations were performed on Ca2+ with different degrees of hydration with the DFT/r2SCAN-3c method together with the implicit solvation model SMD. RESULTS: Ca2+ dehydration energy by quantum calculations, in an aqueous medium, coincides with the experimental results of the energy of the photon emitted in biofield therapies and lasers. This strongly suggests that the increased intracellular free calcium concentration is because of calcium ion dehydration upon the application of radiation. The Ca2+ dehydration increases the membrane potential due to an augment of the net charge on Ca2+ and it moves near the membrane by the attraction of its negative ions. The voltage-dependent channels are also activated by this membrane potential. CONCLUSION: The increased intracellular Ca2+ concentration occurs with biofield therapy (BFT) or laser. A novel explanation is given based on resonance-induced Ca2+ dehydration with applied radiation, supported by experimental data and theoretical calculations.

2.
Braz. J. Pharm. Sci. (Online) ; 58: e20101, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1403732

RESUMO

Abstract Ligustrazine is widely used for the treatment of cardiovascular diseases in traditional Chinese medication. It has been reported that Ligustrazine decreases the concentration of intracellular calcium ions (Ca2+); however, the underlying mechanism remains unknown. In the present study, the effect of Ligustrazine on adenosine diphosphate (ADP)-induced platelet aggregation was evaluated using a turbidimetric approach. The changes in concentration of intracellular Ca2+ stimulated by ADP was measured using fluo-4, a fluorescent Ca2+ indicator dye. The mRNA expression of stromal interaction molecule l (STIM1) and Orai1, calcium sensor, was determined using real-time PCR. In addition, the protein expression of STIM1, Orai1, and serum/glucocorticoid-regulated protein kinase 1 (SGK1) was determined using Western blot analysis. The data demonstrated that Ligustrazine significantly suppressed platelet aggregation in a dose-dependent manner and reduced the concentration of intracellular Ca2+ triggered by ADP. Our data showed that Ligustrazine treatment inhibited the expression of STIM1 and Orai1 induced by ADP at both mRNA and protein levels, and suppressed the protein expression of SGK1. Taken together, our data indicated that Ligustrazine suppressed platelet aggregation by partly inhibiting the activities of calcium sensors, thereby suggesting that Ligustrazine may be a promising candidate for the treatment of platelet aggregation.


Assuntos
Animais , Masculino , Ratos , Proteínas Quinases , Doenças Cardiovasculares/patologia , Agregação Plaquetária , Difosfato de Adenosina/farmacologia , Western Blotting/métodos , Cálcio/agonistas , Povo Asiático/classificação , Moléculas de Interação Estromal
3.
J Cell Biochem ; 121(4): 2877-2888, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31692037

RESUMO

Cells can communicate with other neighboring or distant cells through the secretion of extracellular vesicles (EV), composed of a lipid bilayer and bearing surface molecules that allow them to recognize target cells. In this way, EV induce signaling via different mechanisms, modulating the physiological state of the recipient cell. EV have been identified in both male and female reproductive fluids, however, the possible role of EV isolated from female reproductive fluids has become an emerging field only recently. It is known that ejaculated mammalian spermatozoa need to undergo physiological preparation in the female reproductive tract to fertilize the egg. EV secreted by different regions of the female tract constitute signals that may have a key role in regulating sperm functions. The aims of the present study were isolating EV from different regions of the bovine oviduct and analyzing their interaction and physiological effects on spermatozoa. Here, we report the characterization of bovine oviductal fluid EV from the isthmus and ampulla region and their effect on the induced acrosome reaction and signaling events associated with sperm capacitation. EV induced an increase in sperm protein tyrosine phosphorylation, while cell survival of cryopreserved bovine spermatozoa was maintained. We also show that EV uptake regulates the sperm calcium levels by inducing an immediate increase in the intracellular calcium concentration and sperm priming, after a pre-incubation period, of the progesterone-induced intracellular calcium rise. Our data contribute to understand the role of EV in the communication between the female reproductive tract and the sperm physiology, information that may be used to improve the efficiency of reproductive assisted technologies.


Assuntos
Reação Acrossômica , Oviductos/metabolismo , Espermatozoides/metabolismo , Animais , Cálcio/metabolismo , Bovinos , Sobrevivência Celular , Criopreservação , Ejaculação , Tubas Uterinas/metabolismo , Feminino , Luz , Masculino , Fosforilação , Espalhamento de Radiação , Transdução de Sinais , Capacitação Espermática/efeitos dos fármacos , Motilidade dos Espermatozoides , Tirosina/química
4.
Peptides ; 48: 124-33, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23933300

RESUMO

Bradykinin-potentiating peptides from Bothrops jararaca (Bj) discovered in the early 1960s, were the first natural inhibitors of the angiotensin-converting enzyme (ACE). These peptides belong to a large family of snake venom proline-rich oligopeptides (PROs). One of these peptides, Bj-PRO-9a, was essential for defining ACE as effective drug target and development of captopril, an active site-directed inhibitor of ACE used worldwide for the treatment of human arterial hypertension. Recent experimental evidences demonstrated that cardiovascular effects exerted by different Bj-PROs are due to distinct mechanisms besides of ACE inhibition. In the present work, we have investigated the cardiovascular actions of four Bj-PROs, namely Bj-PRO-9a, -11e, -12b and -13a. Bj-PRO-9a acts upon ACE and BK activities to promote blood pressure reduction. Although the others Bj-PROs are also able to inhibit the ACE activity and to potentiate the BK effects, our results indicate that antihypertensive effect evoked by them involve new mechanisms. Bj-PRO-11e and Bj-PRO-12b involves induction of [Ca(2+)]i transients by so far unknown receptor proteins. Moreover, we have suggested argininosuccinate synthetase and M3 muscarinic receptor as targets for cardiovascular effects elicited by Bj-PRO-13a. In summary, the herein reported results provide evidence that Bj-PRO-mediated effects are not restricted to ACE inhibition or potentiation of BK-induced effects and suggest different actions for each peptide for promoting arterial pressure reduction. The present study reveals the complexity of the effects exerted by Bj-PROs for cardiovascular control, opening avenues for the better understanding of blood pressure regulation and for the development of novel therapeutic approaches.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Anti-Hipertensivos/metabolismo , Hipertensão/patologia , Oligopeptídeos/administração & dosagem , Peptidil Dipeptidase A/metabolismo , Inibidores da Enzima Conversora de Angiotensina/metabolismo , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/química , Bothrops/metabolismo , Bradicinina/química , Bradicinina/uso terapêutico , Humanos , Hipertensão/tratamento farmacológico , Peptidil Dipeptidase A/química , Domínios Proteicos Ricos em Prolina , Venenos de Serpentes/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA