Xerostomia Therapy Due to Ionized Radiation Using Preconditioned Bone Marrow-Derived Mesenchymal Stem Cells.

OBJECTIVES: The aim of this study was to describe the process of regeneration of damaged salivary glands due to ionizing radiations by bone marrow mesenchymal stem cells (BM-MSCs) transplantation that have been given hypoxic preconditioning with 1% O2 concentration. MATERIALS AND METHODS: Stem cell culture was performed under normoxic (O2: 21%) and hypoxic conditions by incubating the cells for 48 hours in a low oxygen tension chamber consisting of 95% N2, 5% CO2, and 1% O2. Thirty male Wistar rats were divided into four groups: two groups of control and two groups of treatment. A single dose of 15 Gy radiation was provided to the ventral region of the neck in all treatment groups, damaging the salivary glands. BM-MSCs transplantation was performed in the treatment groups for normoxia and hypoxia 24-hour postradiation. STATISTICAL ANALYSIS: Statistical analysis was done using normality test, followed by MANOVA test (p < 0.05). RESULTS: There was a significant difference in the expression of binding SDF1-CXCR4, Bcl-2 (p < 0.05) and also the activity of the enzyme α-amylase in all groups of hypoxia. CONCLUSION: BM-MSCs transplantation with hypoxic precondition increases the expression of binding SDF1-CXCR4, Bcl-2 that contributes to cell migration, cell survival, and cell differentiation.

Hypoxic preconditioning effect on stromal cells derived factor-1 and C-X-C chemokine receptor type 4 expression in Wistar rat's (Rattus norvegicus) bone marrow mesenchymal stem cells (in vitro study).

AIM: To examine the effect of hypoxic preconditions on the ability of bone marrow stem cells culture mediated expression C-X-C chemokine receptor type 4 (CXCR4) and stromal cells derived factor-1 (SDF-1) in vitro. MATERIALS AND METHODS: Bone marrow mesenchymal stem cells (BMSCs) were derived from 12 femurs of 200 g Wistar male rats. The animals were euthanized before BMSCs isolation. BMSCs were divided into two groups, control group: Normoxic condition 21% O2 and treatment group: Hypoxic condition 1% O2. The characterization of BMSCs was analyzed using flow cytometry by cluster differentiation 34 and cluster differentiation 105. The expression of CXCR4 and SDF-1 measured using immunocytochemistry immunofluorescence label after 48-h incubation in a low-tension oxygen chamber with an internal atmosphere consisting of 95% N2, 5% CO2, and 1% O2. All data were subjected to a normality test and then analyzed using t-test statistic (p<0.05). RESULTS: The characterization of bone marrow stem cells showed positive cluster differentiation 34 and cluster differentiation 105. A hypoxic precondition (1% O2) in culture increases CXCR4 (p=0.000) and SDF-1 expression than normoxic conditions (p=0.000) (p<0.05). CONCLUSION: Hypoxic preconditioning with 1% O2 increase CXCR4 and SDF1 expression.