RESUMO
Chronic constriction injury (CCI) of infraorbital nerve (IoN) results in whisker pad mechanical allodynia in rats and activation glial cells contributing to the development of orofacial pain. Whisker pad mechanical allodynia (von Frey stimuli) was tested pre and postoperatively and conducted during the treatment time. Photobiomodulation (PBM) and vitamins B complex (VBC) has been demonstrated therapeutic efficacy in ameliorate neuropathic pain. The aim of this study was to evaluate the antinociceptive effect of PBM, VBC or the combined treatment VBC â+ âPBM on orofacial pain due to CCI-IoN. Behavioral and molecular approaches were used to analyses nociception, cellular and neurochemical alterations. CCI-IoN caused mechanical allodynia and cellular alterations including increased expression of glial fibrillary acid protein (GFAP) and ionized calcium binding adaptor molecule 1 (Iba-1), administration of VBC (B1/B6/B12 at 180/180/1.8 âmg/kg, s.c., 5 times all long 10 sessions) and PBM therapy (904 ânm, power of 75Wpico, average power of 0.0434 âW, pulse frequency of 9500 âHz, area of the beam 0.13 âcm2, 18 âs duration, energy density 6 âJ/cm2, with an energy per point of 0.78 âJ for 10 sessions) or their combination presented improvement of the nociceptive behavior and decreased expression of GFAP and Iba-1. Additionally, CCI-IoN rats exhibited an upregulation of IL1ß, IL6 and TNF-α expression and all treatments prevented this upregulation and also increased IL10 expression. Overall, the present results highlight the pain reliever effect of VBC or PBM alone or in combination, through the modulation of glial cells and cytokines expression in the spinal trigeminal nucleus of rats.
RESUMO
Este estudo demonstra como a Beta-galactosidase pode ser desativada e reativada usando EDTA e íons metálicos divalentes. A enzima foi desativada após 20 minutos na presença de EDTA. Desativação máxima para a menor concentração de EDTA (10-3 mol.L-1) ocorreu na presença do tampão Tris-HCl. A enzima recuperou 50% de sua atividade inicial após 10 minutos na presença de Mg2+ em concentrações superiores a 0,1mmol.L-1.Concentrações de 10-4 e 10-3 mol.L-1 de Mn2+ e Co2+ foram suficientes para reativar a enzima em 300% comparado ao controle de íons Mn2+ e aproximadamente 100% para íons Co2+. A enzima perdeu gradualmente a sua atividade quando a concentração foi de 10-2 mol.L-1. Ni2+ e Zn2+ foram incapazes de restabelecer a atividade catalítica. Km app e Vmax app foram 1,95 ± 0,05 mmol.L-1 e 5,40 ± 0,86 x 10-2 mmol.min-1.mg-1. A temperatura e pH ótimos foram 34ºC e 7,5. A meia vida da holoenzima foi de 17,5 min a 30ºC e para a apoenzima foi de 11,0 min a 30ºC. Quanto à variação de pH, a apoenzima provou ser mais sensível que a holoenzima.
In this study, it was demonstrated that Beta-galactosidase can be deactivated and reactivated with EDTA and divalent metal ions. The enzyme was deactivated after 20 minutes in EDTA solution. Maximal deactivation at the lowest EDTA concentration (10-3 mol.L-1) occurred in the presence of Tris-HCl buffer (pH 7.0). The enzyme recovered 50% of its initial activity after 10 minutes at Mg2+concentrations higher than 0.1 mmol.L-1. Experimental concentrations of 0.1 mmol.L-1 Mn2+ and 1.0 mmol.L-1 Co2+ were sufficient to reactivate the enzyme to around 300% of the control activity for the Mn2+ ion and nearly 100% for the Co2+ ion. The enzyme gradually lost its activity when the Co2+ concentration was 10-2 mol.L-1. Ni2+ and Zn2+ were unable to restore the catalytic activity. Km app and Vmax app were 1.95 ± 0.05 mmol.L-1 and 5.40 ± 0.86x10-2 mmol.min-1.mg-1, with o-NPG as substrate. Optimal temperature and pH were 34oC and 7.5. The half-life (t1/2) at 30ºC was 17.5 min for the holoenzyme and 11.0 min for the apoenzyme. With respect to pH variation, the apoenzyme proved to be more sensitive than the holoenzyme.
