The Prevalence of the Genetic Polymorphism of GSTM1, GSTT1 and GSTP1 and Its Relationship with Clinical Criteria of Multiple Sclerosis (MS) Patients in Tehran

BACKGROUND AND OBJECTIVE: Multiple Sclerosis is the chronic inflammation of central nervous system with demyelinated lesions in the brain and spinal cord. The genetic polymorphisms associated with glutathione S-transferase enzymes involved in antioxidant defense in Iranian patients have not been investigated. Therefore, in the present study, the prevalence of the genetic polymorphism of glutathione S-transferase M1, P1 and T1 and its relationship with clinical criteria of MS patients with has been examined. METHODS: In this case-control study, 69 patients who referred to Sina Hospital in Tehran and had no panic attack within the last three months and 74 healthy subjects were interviewed. After examination by neurologist and blood sampling, DNA extraction was performed using Roche kit. Then, the genotypic variations of the samples were evaluated using RFLP-PCR and its prevalence was analyzed in relation with age, birth weight, malignancy (EDSS) and gender using GraphPad Prism software. FINDINGS: Most malignancies were observed in men (3.1±5.9) and the highest incidence rate was observed in those born in May (30%). Although the results of genotyping between the studied groups and their gender did not show any significant difference (OR: 2-4, p>0.05), patients with GSTM1 deficiency developed the disease at a lower age (32.8±2.6 years) compared with other patients (29.5±8.9 years) (CI-95%: 20.3–26.4, p=0.009). In addition, people with a rare GSTM1 allele who smoked cigarette had higher EDSS (CI-95%: 2.1–3.7, p=0.03). CONCLUSION: Based on the results of this study, the effect of GSTM1 on malignancy is indicative of its role in detoxification of tobacco products and can be used as an agent for early diagnosis of disease in people who are susceptible to this disease

Cytotoxic effect of a dentin bonding agent: AdheSE

Background and Aim: An important requirement for a dentin bonding agent is biological compatibility. Since dentin bonding agents are placed in cavity preparations with subgingival extensions, with direct contact to gingival and mucosal tissues, tissue response to these materials must be investigated. The aim of this study was to examine the cytotoxicity of AdheSE, a self etching adhesive, on human gingival fibroblasts."nMaterials and Methods: In this experimental in vitro study, primary human gingival fibroblasts were exposed to different dilutions of primer & bond of AdheSE (Vivadent, Liechtenstein). The toxicity of the primer was tested in 30 seconds, 300 seconds and 24 hours. The cytotoxicity of the bond was analyzed in uncured mode after 20 seconds, 5 minutes and 24 hours. In cured mode, tested materials were analyzed after 24 and 48 hours. Cytotoxic effects were evaluated using MTT, cell counting and DNA condensation assays. Data were analyzed by two way repeated measure ANOVA with p<0.05 as the level of significance."nResults: MTT Assay revealed that uncured AdheSE Bond was toxic only in 10-1 dilution and the difference with control group was significant (P<0.05). By increasing the time to 300sec. and 24h, dilutions of 10-2 and 10-4 were the most cytotoxic respectively. Cytotoxicity of uncured primer after 30 sec. and 300 sec. began from 10-2 and after 24h began from 10-2 and reached to 10-1. AdheSE in cured mode showed significant difference with control group in 1:2 (P<0.001),1:4 & 1:6 (P<0.01) dilutions. In cell counting assay only the 1:2 dilution was significantly more toxic than control group. Apoptosis (a morphological and biochemical distinct form of cell death that regulates cell turnover) comprised in less than 5% of total death in both cured and uncured adhesives."nConclusions: Based on the results of this study, by increasing the exposure time, smaller amounts of bonding could be cytotoxic. Cytotoxicity was related to material, dilution, time of exposure and curing. It would be necessary to identify the toxic ingredients of this adhesive and replace them by more biocompatible components

The Neuroprotective Effect of Lithium in cannabinoid Dependence is Mediated through Modulation of Cyclic AMP, ERK1/2 and GSK-3β Phosphorylation in Cerebellar Granular Neurons of Rat

Lithium (Li), a glycogen synthase kinase-3β (GSK-3β) inhibitor, has used to attenuate the cannabinoid-induced dependence/withdrawal signs, but molecular mechanisms related to this are unclear. Recent studies indicate the involvement of upstream extracellular signal kinase1/2 (ERK1/2) and downstream GSK-3β pathways in the development of cannabinoid-induced dependence. This is mediated through cannabinoid receptor 1 (CB1) enriched in cerebellar granular neurons (CGNs). Accordingly, the present study aimed to investigate the mechanism of modulatory/neuroprotective effects of Li on a cannabinoid agonist (WIN 55,212-2 (WIN))-induced dependence, through quantitative analysis of some involved proteins such as ERK1/2, GSK-3β and related signaling pathways including their phosphorylated forms; and cAMP level as the other molecular mechanisms leading to dependence, in CGNs model. The CGNs were prepared from 7-day-old Wistar rat pup in a 12-well plate, pretreated with Li (1mM) and an ERK1/2 inhibitor SL327 (SL, 10 µM). The WIN (1 µM) was added 30 minutes prior to treatment and AM251 (AM, 1 µM), as a cannabinoid antagonist was co-treated with WIN. The cAMP level, as an indicator of cannabinoid-induced dependence, was measured by ELISA following forskolin (FSK) stimulation. Western blot analyses determined the phosphorylated forms of ERK1/2 (p-ERK1/2), GSK-3β (p-GSK-3β) as well as their total expressions in various treatment times and doses in CGNs. WIN alone could down regulate the cAMP/p-ERK1/2 cascade compared to AM treatment. However, P-GSK-3β was up-regulated with Li and WIN or with SL and Li pretreatment to AM-induced cellular response, which was the highest 60 minutes after CGNs exposure. Results further suggested the potential role of Li pretreatment to diminish the development of cannabinoid-induced dependence/neuronal injury through possible mechanisms of modulating the cAMP/p-ERK1/2 cascade independent of p-GSK-3β signaling pathway in-vitro