RESUMO
INTRODUCTION: Methamphetamine (MA) acts as a powerful oxidant agent, while Rosmarinic Acid (RA) is an effective herbal antioxidant. Oxidative stress-mediated by MA results in apoptosis, and caspase-3 is one of the critical enzymes in the apoptosis process. MA can epigenetically alter gene regulation. In this paper, to investigate the effects of RA on MA-mediated oxidative stress, changes in the level of casp3a mRNA were demonstrated in zebrafish. METHODS: The animals were grouped in 3 treatment conditions for the behavioral test: control, MA, MA pretreated by RA, and 6 treatment conditions for the molecular test: control, RA, MA, MA co-treated with RA, MA co-treated with RA/ZnO/chitosan nanoparticle, and ZnO/chitosan nanoparticle. Then molecular and behavioral investigations were carried out, and critical comparisons were made between the groups.MA solution was prepared with a concentration of 25 mg/L, and RA solution was prepared by DPPH test with the antioxidant power of about 97%. Each solution was administered by immersing 20 zebrafish for 20 minutes, once per day for 7 days. The level of casp3a mRNA was quantified by using qRT-PCR. One-sided trapezoidal tank diving test was applied to study behavioral alterations. RESULTS: The qPCR analysis demonstrated the high potential of RA/ZnO/chitosan in counteracting the MA-mediated elevation in casp3a mRNA level. Based on the diving test results of MA-treated fish, MA was found to be anxiolytic compared to the control. While the resulted diving pattern of the MA-treated animals pretreated by RA was novel and different from both the control and MA-treated groups. CONCLUSION: The potential of RA combined with a suitable nanoparticle against MA-induced oxidative stress was supported. The high efficiency of ZnO/chitosan in increasing RA penetration to the brain cells was evident. MA at a dose of 25 mg/L is anxiolytic for zebrafish. However, the molecular mechanisms involved in these processes should be studied.
RESUMO
It is reported that dihydroxy chalcones have analgesic and anti-inflammatory effects. Study of the structure activity relationship (SAR) shows that benzofuran-3-one derivatives may be more effective in this respect. In this study, a new (Z)-2-(3,4-dihydroxybenzylidene)-5-methoxybenzofuran-3(2H)-one (compound 5) was synthesized and its analgesic and anti-inflammatory effects were evaluated by formalin, carrageenan and hot-Plate methods in mice. The results showed that, compound 5 induced significant antinociceptive and anti-inflammatory effect (P<0.01). Maximum analgesia (42.6%) was obtained at dose of 25 mg/kg in the first phase of formalin test. The effect of compound 5 was higher (87.7%) in chronic phase of inflammation induced by formalin (P<0.01). Administration of 25 mg/kg of compound 5 inhibited the inflammation induced by carrageenan, 32.8% and 41.7%, 1 and 3 hour after carrageenan injection, respectively. In addition, this dose of compound 5, induces significant analgesia (20.2%) in hot plate test 45 minutes after injection (P<0.01). Therefore it seems that compound 5 has potential for discovery of a compound with potent anti-inflammatory and analgesic effects and its scaffold could be use for further structural modifications.
