The expression of cytochrome P4502J2 gene and 14, 15 epoxyeicosatrienoic acid level influence the amount of insulin secreted from human mesenchymal stem cell-derived insulin-producing cells

Abstract Background Insulin-producing cells differentiated from human mesenchymal stem cells demonstrate limited glucose-stimulated insulin secretion. Cytochrome P450 2J2 and its product epoxyeicosatrienoic acids regulate β-cell function in the human pancreas. The aim of this study is to explore the expression pattern of cytochrome P450 2J2 gene and 14, 15 epoxyeicosatrienoic level along the differentiation of human bone marrow-derived mesenchymal stem cells into insulin-producing cells. Results The differentiated insulin-producing cells express high levels of pancreatic duodenal homeobox-1 and insulin gene mRNA. It secretes increasing amounts of C-peptide in response to increasing glucose concentrations than undifferentiated cells. The differentiated insulin-producing cells were found to express reduced amounts of cytochrome P450 2J2 gene mRNA and significant low level of 14, 15 epoxyeicosatrienoic acid than the undifferentiated cells. A strong positive correlation between 14, 15 epoxyeicosatrienoic concentrations and C-peptide released from the differentiated insulin-producing cells was noticed. Conclusions Cytochrome P4502J2 and its product 14, 15 epoxyeicosatrienoic might affect insulin secretion from differentiated insulin-producing cells

Impact of Helicobacter pylori infection on liver fibrosis in Egyptian patients with chronic hepatitis C

Both Helicobacter pylori (HP) and hepatitis C virus (HCV) infections are endemic in Egypt. This work aimed to investigate the presence of HP in the liver of patients with chronic hepatitis C (CHC) and explore the relation between HP infection, liver histopathology and HCV viral load. The study included 60 patients with CHC. Virological, biochemical, liver biopsy and testing for anti-Hp and anti-schistosomal antibodies in serum were done. Liver tissues were examined for histopathological and presence of Hp by detection of HP 16S rRNA gene by PCR and sequence analysis. Anti-schistosomal and anti HP antibody was found in 45% and 61.7%, respectively. Low stages of fibrosis (F0–F3) were found in 73.3% and advanced fibrosis (F4–F6) in 26.7%. HP DNA was found in 10% of the liver specimens. Although the frequency HP antibodies was equally high in patients with advanced and low fibrosis (68.8% and 59.1%, P > 0.05), the HP DNA in liver tissue was significantly more frequent in patients with advanced fibrosis (31.25% vs. 2.7%, P = 0.004). Meanwhile, the median viral load of HCV was higher in patients with HP DNA in liver tissue compared to patients with no HP DNA in liver tissue (337.000 vs. 165.000, P = 0.3491). HCV RNA titer, fibrosis score and history of blood transfusion, are independent factors associated with HP DNA in liver tissue. In conclusion, the presence of HP in liver tissue of patients with advanced fibrosis suggests a potential relation between HP infection and progression of liver fibrosis due to HCV

Non-additive effect of the DNA methylation inhibitor, 5-Aza-dC, and glass as a culture surface on osteogenic differentiation

The clinical need for bone regenerative solutions is expanding with increasing life expectancy and escalating incidence of accidents. Several strategies are being investigated to enhance the osteogenic differentiation of stem cells. We previously reported two different approaches for this purpose, in monolayer and three-dimensional cell culture. The first approach was based on pretreating cells with 5-Aza-dC, a DNA methylation inhibitor, before the applying the differentiation media. The second approach was based on culturing cells on a glass surface during differentiation. In this study, we investigated the potential effect of combining both methods. Our results sug-gested that both approaches were associated with decreasing global DNA methylation levels. Cells cultured as a monolayer on glass surface showed enhancement in alkaline phosphatase activity at day 10, while 5-Aza-dC pretreatment enhanced the activity at day 5, irrespective of the culture surface. In three-dimensional pellet cul-ture, 5-Aza-dC pretreatment enhanced osteogenesis through Runx-2 and TGF-beta 1 upregulation while the glass surface induced Osterix.Furthermore, pellets cultured on glass showed upregulation of a group of miRNAs, including pro-osteogenesis miR-20a and miR-148b and anti-osteogenesis miR-125b, miR-31, miR-138, and miR-133a. Interestingly, 5-Aza-dC was not associated with a change of miRNAs in cells cultured on tissue culture plastic but reverted the upregulated miRNAs on the glass to the basal level. This study confirms the two approaches for enhancing osteogenic differentiation and contradicts their combination.Funding Agencies|University of Sharjah; [180-1090-127P]</p