International Journal of Molecular and Cellular Medicine
Volume:4 Issue: 13, Winter 2015

Membrane/ protein trafficking in the secretory/ biosynthetic and endocytic pathways is mediated by vesicles. Vesicle trafficking in eukaryotes is regulated by a class of small monomeric GTPases; the Rab protein family. Rab proteins represent the largest branch of the Ras superfamily GTPases, and have been concerned in a variety of intracellular vesicle trafficking and different intracellular signalling pathways. Rab11 (a subfamily of the Ypt/ Rab gene family), an evolutionarily conserved ubiquitously expressed subfamily of Rab GTPases, has been implicated in regulating vesicular trafficking through the recycling of endosomes. Rabs have been grouped into different subfamilies based on the distinct unambiguous sequence motifs. Three members: Rab11a, Rab11b and Rab25 make up the Rab11 GTPase subfamily. In this review article, we describe an overview over Rab11 subfamily with a brief structural aspect and its roles in implicating different disease progression.

The importance of mesenchymal stem cells (MSCs), as adult stem cells (ASCs) able to divide into a variety of different cells is of utmost importance for stem cell researches. In this study, the ability of cartilage extract to induce differentiation of rat derived omentum tissue MSCs (rOT-MSCs) into chondrocyte cells (CCs) was investigated. After isolation of rOT-MSCs, they were co-cultured with different concentrations of hyaline cartilage extract and chondrocyte differentiation was monitored. Expression of MSCs markers was analyzed via Flow cytometry. Moreover, expression of octamer- binding transcription factor-4 (Oct-4), Wilm''s tumor suppressor gene-1 (WT-1), aggreacan (AG), collagen type-II (CT-II) and collagen type-X (CT-X) was analyzed using RT-PCR on 16, 18 and 21 days. Furthermore, immunocytochemistry and western blot were performed for CT-II production. Finally, Proteoglycans (PGs) were examined using toluidine blue and alcian blue staining. The phenotypic characterization revealed the positive expression of CD90, CD44 and negative expression of CD45 inrOT-MSCs. These cells also expressed mRNA of Oct-4 and WT-1 as markers of omentum tissue. Differentiated rOT-MSCs in the presence of 20 µg/ ml cartilage extract expressed AG, CT-II, CT-X, and PGs as specific markers of CCs. These observations suggest that cartilage extract is potentially able to induce differentiation of MSCs into chondrocyte lineage and may be considered as an available source for imposing tissue healing on the damaged cartilage. More investigations are needed to prove in vivo cartilage repair via cartilage extract or its effective factors.

Neural stem cells (NSCs) as a heterogeneous multipotent and self- renewal population are found in different areas in the developing mammalian nervous system, as well as the sub-ventricular zone (SVZ) and the hippocampus of the adult brain. NSCs can give rise to neurons, astrocytes and oligodendrocytes. The aim of this study was to differentiate neural stem cells into noradrenergic–like cells in vitro. Neural stem cells were harvested from SVZ of newborn rat brains. The cells were cultured in DMEM12, B-27 supplemented with 20 ng/ ml (hFGF) and 20 ng/ ml (EGF) for 2 weeks. Neurospheres were differentiated in neurobasal medium, B-27 supplemented with BDNF (50 ng/ ml) and GDNF (30 ng/ ml) for 3 and 5 days. Cell culture techniques and immunocytochemistry were applied to examine neurospheres and tyrosine hydroxylase positive cells. The number of neurites was counted 3 and 5 days after the induction of differentiation. Nestin and Sox2 were expressed in NSCs and neurospheres. NSCs were differentiated into noradrenergic- like cells (NACs). Tyrosine hydroxylase was detected in these cells. The results of NSCs differentiation for 5 days culture had a significant decrease (P≤0.05) in the number of TH positive cells with one or two neurite per cell, and a significant increase (P≤0.05) in the number of TH positive cells with three, four or more neurites per cell, compared with 3 days culture. Based on these results, NSCs have the ability to differentiate into noradrenergic cells in the presence of BDNF and GDNF growth factors.

Bladder cancer (BC) ranks the second most common genitourinary tract malignant tumor with high mortality and 70% recurrence rate worldwide. MiRNAs expression has noticeable role in bladder tumorigenesis. The purpose of this study was to assess miR-200c, miR-30b and miR-141 in tissue samples of patients with BC and healthy adjacent tissue samples and their association with muscle invasion, grade and the size of the tumor. Transurethral resection tissue samples were collected from thirty- five newly diagnosed untreated patients with BC from 2013 to 2014. The control group consisted of adjacent normal urothelium. All samples, observed by two pathologists, were diagnosed transitional cell carcinomas (TCC) with the proportion of tumor cells greater than 80%. Total RNA including miRNAs was extracted from about 50 mg tissue samples by applying TRIzol reagent. 2(-ΔΔ CT) method was used to calculate relative quantification of miRNA expression. Two of 35 patients were females and the other 33 were males. Invasion to bladder muscle was observed in 23 (67%) cases. MiR-141, miR-200-c and miR30-b were up-regulated in 91%, 79% and 64% of malignant tissues, respectively. Down-regulation of miR-141 had a strong association with muscle invasion (P= 0.017). Significant inverse correlation between grading and miRNA-141 level was observed (P= 0.043).

Single-nucleotide polymorphisms (SNPs) in miRNAsmay alter its expression levels or processing and contribute to susceptibility to a wide range of diseases. Our study aimed to evaluate the possible association between miRNA-146a rs2910164 and miRNA-499 rs3746444 polymorphisms and susceptibility to pulmonary tuberculosis (PTB) in a sample of Iranian population. This case- control study was performed on 202 PTB patients and 204 healthy individuals. Genotyping was performed using tetra amplification refractory mutation system-polymerase chain reaction (T-ARMS-PCR). The results indicated that neither miRNA-499 rs3746444 nor miRNA-146a rs2910164 are associated with the risk of PTB in a sample of Iranian population. Larger studies with different ethnicities are required to validate our findings.

The emergence of multidrug resistance (MDR) and extensively drug resistance (XDR) in Acinetobacter baumannii has made an important challenge in the treatment of infections caused by this organism. The ability of carbapenemase production is one of the main mechanisms for the emergence of MDR and/or XDR in A. baumannii. The aim of this study was to detect carbapenemase producer A. baumannii. In this study, 65 imipenem resistant A. baumannii were collected from burned patients. Biochemical identification, antibiotic susceptibility test and multiplex polymerase chain reactions for the detection of carbapenemases genes were performed. The results showed that all strains carried blaOXA-51. 83%, 12.5% and 9.23% strains harbored blaOXA-23, blaVIM and blaKPC genes, respectively. None of the isolates carried blaIMP, blaOXA-48, blaNDM-1 and blaSPM-1 genes. The results of this study indicate the emergence of Klebsiella pneumoniae Carbapenemase (KPC) in A. baumannii causing nosocomial infections in burned patients which can be important for hospital infection prevention systems in Iran.

The reliability of gene expression profiling based technologies and methods to find transcriptional differences representative for the original samples is influenced by the quality of the extracted RNA. Hence, RNA extraction is the first step to investigate the gene expression and its function. Consequently, the quality of extracted RNA is really significant. Correspondingly, this research was accomplished in order to optimize the RNA extraction methods and compare the tissue amounts or tissues quality. Relatively, the cancerous tissues of human''s stomach in fresh and frozen conditions and also the mouse''s fresh tissue were studied. Some factors like the amount of samples, efficacy differences of diverse extraction''s buffers (TriPure, Trizol) and also the efficacy of b-mercaptoethanol were compared and investigated. The results indicated that the less amount (1-2 mg) compared to other amounts (2-5 mg, 5-15 mg) yielded the best quality and the RNA''s bands (5S, 18S, 28S) were observed perfectly. Relatively, comparing and measuring some kinds of buffers (Trizol, TriPure) indicated no difference in RNA extraction quality. The last investigated factor was the effect of b- mercaptoethanol which was used along with TriPure in order to remove the RNAse. Conclusively, no effective impression was observed.

Osteonectin is a bone- associated protein involved in vascular calcification. Adiponectin may protect against cardiovascular disease but possible effects on vascular calcification have been poorly studied. The aim of this study was to investigate the modulatory effect of adiponectin on oxidized low density lipoprotein (oxLDL)- induced expression of osteonectin in human aorta vascular smooth muscle cells (HA/VSMCs). HA/VSMCs were cultured in F12K media and then treated with oxLDL (100 µg/mL) in the presence or absence of adoponectin (5 µg/mL) for 24 and 48 hours. mRNA expression and protein level of osteonectin were determined by quantitative real-time PCR and western blot analysis, respectively. After exposure to oxLDL, osteonectin expression increased 1.62 ± 0.23- and 6.62 ± 0.48-fold after 24 and 48 hours respectively compared to the control. Adiponectin increased oxLDL- induced osteonectin expression in a time-dependent manner after 24 and 48 hours (3.24 ± 0.39- and 24.93 ± 2.15-fold, respectively). Western blotting confirmed that osteonectin protein was upregulated by adiponectin.Our data suggest that OxLDL might cause the increase of osteonectin expression both at mRNA and protein level. This upregulation is intensified by adiponectin.