Background: Many studies have focused on oxidative stress induced damage and hence, the protective effects conferred by antioxidants. An example is neurodegenerative diseases which is thought to occur due to neuronal loss associated with oxidative stress. However, some antioxidants such as vitamin E have been shown to also exert pro-oxidative effects at high concentration. Objective: In this study the cytotoxicity and neuroprotective potentials of Chlorella vulgaris (CV), Momordica charantia (MC) and Piper betle (PB) were investigated and correlated with the antioxidant potential. Tocotrienol Rich Fraction (TRF) served as positive control since it had been shown previously to have high antioxidant potential as well as to exert neuroprotective and neurocytotoxic effects. Method: Free radical scavenging activities of hot water extract of CV, aqueous extract of MC, aqueous extract of PB and TRF were determined by using DPPH (1, 1-diphenyl-2-picryl-hydrazyl) assay. Cytotoxicity and neuroprotective effects were measured by using 3 - (4, 5 -dimethylthiazol-2-yl) -5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium salt (MTS) against BSO-induced neuron cell death. Results: Results showed that TRF has the highest radical scavenging activity followed PB> MC>CV. The MTS results showed that TRF (1-50mg/ml) as positive control, PB (0.001-100mg/ml) and MC (1-500mg/ml) conferred significant protection against BSO-induced cell death. These plants were cytotoxic at high concentrations. However CV extract did not show significant neuroprotective effect against BSO-induced cell death nor cytotoxic effect. Conclusion: The present findings showed that plant extracts with the higher free radical scavenging activity showed neuroprotective effects at low concentrations but were cytotoxic at higher concentrations.

Introduction: Today, due to high rates of accidents and fractures leading to bone defects and due to the limited possibility of bone graft bonding, using the patient’s cell culture on appropriate scaffolds and transferring it to the defect area is suggested as one of the treatment plans.Materials and methods: Bone samples of 8 male subjects that were under craniotomy surgery in the hospital were collected. First, the samples were cut into smaller pieces and then, transferred to incubator culture dishes. Two weeks later, the osteoblast activity on the bone matrix began and on average, the cells covered the dishes within two weeks. The first generation of the cells was re-moved by Trypsin_EDTA method from the opaltes, then were divided into two parts, one was added to alginate gel and the other to monolayer culture. In order to prove the osteoblast activity on the bone matrix and investigate these activities, Van Kossa staining method was used, and also to investigate the cell viability, MTT method was employed.Results: There was a significant difference in the number of the cells created in alginate gel and those created in monolayer after two weeks (P<0.001). Moreover, the difference between mean cell counts in alginate gel and monolayer was statistically significant (P<0.001). The results of the MTT test in second week showed that the number of alive cells is significantly higher in alginate gel (P<0.001). Finally, the result of the Van Kossa method proved extracellular matrix in both experimental groups.Conclusion: Results showed that alginate gel better can support duplication and survival of osteoblasts compared to monolayer culture. This may be attributed to the biological properties of this gel; alginate gel porosity provides conditions under which cellular and metabolic activities are accelerated.