Alzheimer is a progressive neurological disease that results in irreversible loss of neurons and includes about two thirds of all cases of dementia. Toxoplasma gondii may be an important infectious agent involved in neurodegenerative diseases. The aim of this study was to investigate the correlation between Toxoplasma as an etiologic agent in the progress of Alzheimer's disease. This case control study was conducted on 75 Alzheimer's patients and 75 healthy volunteers. Blood samples were obtained and anti-Toxoplasma IgG and IgM tests were done by using ELISA technique. DNA was extracted from buffy coat and then GRA6 gene and SAG2 loci were amplified by PCR and nested PCR, respectively. Chi-square, Fisher's test, and binary logistic regression were used for data analysis. A percentage of 61.3 % of Alzheimer's patients and 62.6 % of healthy volunteers were positive for anti-Toxoplasma IgG but all participants were negative for anti-Toxoplasma IgM. There were no significant differences between Alzheimer's patients with their controls in terms of anti-Toxoplasma IgG antibody (P = 0.5). Due to lack of positive IgM sample, results of the molecular methods were negative by GRA6 and SAG2 fragments amplification. This result shows that, infection with T. gondii cannot be considered as a risk factor for etiology and developing Alzheimer's disease.

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Background: We aimed to investigate the effect of miR-15a mimic and inhibitor of miR-155 expression on apoptosis induction in macrophages infected with Iranian strain of Leishmania major in-vitro and in-vivo. Methods: RAW 264.7 cells were infected with L. major promastigotes (MRHO/IR/75/ER), and then were treated with miRNAs. For in-vivo experiment, BALB/c mice were inoculated with L. major promastigotes, and then they were treated with miRNAs. For evaluation of miRNA therapeutic effect, in-vitro and in-vivo studies were performed using quantitative Real-time PCR, Flow cytometry, lesion size measurement, and Limiting Dilution Assay (LDA). This study was performed in Shahid Beheshti University of Medical Sciences in 2019. Results: In-vitro results of flow cytometry showed that using miR-15a mimic, miR-155 inhibitor or both of them increased apoptosis of macrophages. In in-vivo, size of lesion increased during experiment in control groups (P<0.05) while application of both miR-155 inhibitor and miR-15a mimic inhibited the increase in the size of lesions within 6 wk of experiment (P=0.85). LDA results showed that microRNA therapy could significantly decrease parasite load in mimic or inhibitor receiving groups compared to the control group (P<0.05). Conclusion: miR-155 inhibitor and miR-15a mimic in L. major infected macrophages can induce apoptosis and reduce parasite burden. Therefore, miRNA-based therapy can be proposed as new treatment for cutaneous leishmaniasis.

Toxoplasma gondii is an obligate intracellular parasite that infects all nucleate cells of vertebrates. Human infected by vertical transmission and also using raw or undercooked meat or food and water that contaminated with mature oocysts. Parkinson's disease as neurodegenerative disease affects people above 60 years. Due to high prevalence of toxoplasmosis in Iran and evidence about effects of T. gondii on neurodegenerative diseases, this study has been conducted to investigate possible correlation between Toxoplasma and Parkinson's disease in Iran. Seventy five Parkinson's patients and equal healthy volunteers were enrolled. After obtaining informed consent and sociodemographic features, 5 ml blood sample were collected and then anti-Toxoplasma IgG and IgM levels were examined by ELISA method. Data was analyzed with Chi-squre and Fisher's test by usig stata 11 software. Binary logistic regression was used for multivariate analysis in assessing the correlation between toxoplasmosis and Parkinson. Eighty five percent of Parkinson's group and 90.3 % of control group were positive for anti-Toxoplasma IgG antibody. In this investigation no statically differences were observed between groups and age, gender, residency and using raw or undercooked meat. There is no significant association between IgG positive titer and Parkinson's disease. However, statistically significant association was found between Parkinson and keeping cat (P = 0.03) as well as the using of undercooked egg (P = 0.004). Although there is high level of anti-Toxoplasma IgG antibody in Parkinson's patients which reflects chronic Toxoplasma infection; we couldn't detect any statistical association between T. gondii infection and Parkinson's disease.

Background: Cutaneous Leishmaniasis (CL) is an emerging uncontrollable and neglected infectious disease worldwide including Iran. The aim of this study was to investigate the expression profile of apoptosis- related miRNA and its target gene in macrophages. Methods: This study was carried out in the Department of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran from January 2016 to November 2018. Applying literature reviews, bioinformatics software, and microarray expression analysis, we selected miRNA-24-3p interfering in apoptosis pathway. The expression profile of this miRNA and target gene were investigated in Leishmania major (MRHO/IR/75/ER)-infected primary and RAW 264.7 macrophages (IBRC-C10072) compared with non-infected macrophages (control group) using quantitative Real-time PCR. Results: Results of bioinformatics analysis showed that miR-24-3p as anti-apoptotic miRNA inhibits pro-apoptotic genes (Caspases 3 and 7). Microarray expression data presented in Gene Expression Omnibus (GEO) revealed a significant difference in the expression level of selected miRNA and its target gene between two groups. QRT-PCR results showed that the expression of miR-24-3p was upregulated in L. major infectioned macrophages that approved the results of bioinformatics and microarray analysis. Conclusion: Parasite can alter miRNAs expression pattern in the host cells to establish infection and its survival. Alteration in miRNAs levels likely plays an important role in regulating macrophage functions following L. major infection. These results could highlight current understanding and new insights concerning the gene expression in macrophages during leishmaniasis and will help to development of novel strategies for control and treatment of CL.