Background: Progesterone is a female steroid hormone that has a potent anticonvulsant effect on human and animal. The aim of this study was to investigate the involvement of opioid receptors in the anticonvulsant effect of progesterone on ovariectomized mice.

Materials and Methods: In this experimental study, all animals were ovariectomized. After two weeks, they received an intraperitoneal (i.p.) injection of drugs (progesterone and naloxone) or saline. The animals also received a subcutaneous injection of strychnine for induction of convulsive seizures, 30 minutes after administration of drugs or saline. For evaluation of convulsion in the animals, convulsion onset time, convulsion duration, the number of seizures, and death time were recorded.

Results: Progesterone (25 and 50 mg/kg, i.p.) decreased the strychnine-induced convulsion. The anticonvulsant effect of 50 mg/kg of progesterone was abolished by naloxone (5 mg/kg, i.p.) injection, whereas administration of the same doses of naloxone alone did not affect strychnine-induced convulsion.

Conclusion: These results suggest that opioid receptors may play an important role in the anticonvulsant effect of progesterone.

Background: All-trans retinoic acid(RA), an active metabolite of vitamin A, is widely used to induce cell differentiation. It has significant effects on growth and proliferation of epithelial cells. It also causes cell cycle arrest in G0/G1 phase and induces the apoptosis. cisplatin, a chemotherapy compound that cross-linking to DNA, and leads to apoptosis, it is commonly used for treatment of ovarian, head and neck, esophageal, gastric cancers and melanoma. Recent studies showed that RA enhances cytotoxic effects of cisplatin on melanoma and ovarian cancer. Our literature review showed that there is no previous study on the effect of RA in combination with cisplatin on esophageal cancer, hence current study conducted to investigate such combination treatment on esophageal derived cell, KYSE-30.

Materials and Methods: KYSE30 cell line was cultured in presence of different concentration of RA alone and in combination with cisplatin. Then, cell death was investigated by colonogenic assay and acridine orange/ ethedium bromide staining.

Results: The results showed that RA concentrations &ge15µM cause differentiation of KYSE30 to squamous cell morphology, while lower concentrations decreases the colony formation (p&le0.05). These effects were also observed in combination with cisplatin and RA. The best effects on cell death were observed in 10 µM of RA of combination with 5 and 10 µg/ml of cisplatin.

Conclusion: The results suggest that low concentration of RA in combination with cisplatin are more effective than cisplatin alone in terms of apoptosis and necrosis of esophageal cancer, KYSE-30.

Background: Melanoma is a malignant tumor of melanocytes, early-stage melanomas can be treated effectively with surgery alone, but more advanced cancers often incurable. The incidence of melanoma malignancy in most countries has risen faster than any other cancer types. It was the first time which we evaluated the cytotoxic effects of zno and Ag/zno nano-composites (NP) on melanoma cell line, A375, viability.

Materials and Methods: In this experimental study, A375 cell line was grown in RPMI-1640 supplemented with 10% FBS, penicillin/streptomycin (100 U/ml, 100 µg/ml) at 37◦C in 5% CO2, then the effects of different concentrations of zno and Ag/zno nano-composites on melanoma cell were evaluated by MTT, clonogenic survival assays, and acridine orange/ ethidium bromide staining.

Results: Herein, we demonstrated that Zno and Ag/zno nano-composites showed similar effects on cytotoxicity of melanoma cancer cells. In a dose dependent manner, a significant cytotoxicity was observed with increasing of zno and Ag/zno. The inhibitory concentration 50% (IC50) values of the nano-composites for A375 cell line after 24 hrs were 7.24±1.55 and 15.93±1.73 µg/ml for zno and Ag/zno, respectively.

Conclusion: The results showed that zno and Ag/zno has ability to induce cytotoxicity in the human melanoma cancer cell line in lower micromolar concentrations. In conclusion, these findings may introduce a new view on the mode of action and possible application of new nano-composites in the cancer chemotherapy.

Background: Renal injury following ischemia - reperfusion (I/R) is still an unavoidable problem in many remedial and medical situations. Portulaca oleracea (PO) has been known for its anti-oxidative effects. Then, the present study aimed to investigate the effect of ethanolic extract of PO (EEPO) on the renal function and antioxidant status after induction of I/R injury in the rat kidney.

Materials and Methods: A total of 30 rats (Wistar) were divided into five groups (n = 6 each). Sham group: underwent laparotomy without I/R, EEPO group: EEPO administered 300 mg/kg then was operated like sham, I/R group: was underwent renal ischemia/reperfusion only, EEPO150+ I/R and AEPO300+ I/R groups: were administered PO 150 and 300 mg/kg then underwent I/R operation. PO extract was administered for 5 days in the relevant groups by gavage. Serum urea and creatinine (Scr), the level of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH) and total antioxidant activity (TAA) were determined. Data were analyzed by ANOVA and post hoc LSD test. P values of 0.05 or less were considered statistically significant.

Results: Induction of I/R and pretreatment with PO extract, increased the level of superoxide dismutase (SOD) in comparison with sham group (p<0.05, p<0.001). There were no significant differences in the levels of MDA, GSH and TAA among different groups. On the other hand, the Scr and serum urea of the I/R and treated groups were elevated compared to the sham group (p<0.001).

Conclusion: Ethanolic extract of PO did not strongly affect the renal antioxidant status and could not prevent the renal injury following I/R.