Chemokine Receptors Expression in MSCs: Comparative Analysis in Different Sources and Passages

MSC-based therapy is providing a cure for degenerative diseases with unmet medical need and usually iliac crest bone marrow (ICBM) are being applied in clinics. Alternative sources, including adipose tissue and reamer/irrigator/ aspirator hold great potential for isolating MCSs. Here, we compared original MSCs features of adipose tissue (Ad-MSCs) and bone marrow of long-bone (RIA-MSCs) or iliac crest, and the expression of chemokine receptors (including CXCR4, CX3CR1, CXCR6, CXCR2, CCR1 and CCR7) in these three sources, which are important in the context of homing. We further investigated the role of SDF-1/CXCR4 axis as a key player in motility of different population of MSCs using Transwell migration assay. All cells exhibited typical MSCs characteristics. However, different MSCs sources expressed different levels of chemokine receptors. Generally, the expression of these chemokine receptors was decreased with increasing passage (P) number from 2 to 3. Interestingly, it was observed that the CXCR4 expression and migration capacity in Ad-MSCs is significantly higher than ICBM and RIA-MSCs in P2. Although our data showed that CXCR4 had highest expression in P2 Ad-MSCs, but it dramatically declined following sub-culturing in the P3. Hence, to improve homing of MSCs by means of chemokine/their receptors axis, the source of isolation and passage number should be considered for clinical applications.

Three-dimensional scaffold from decellularized human gingiva for cell cultures: glycoconjugates and cell behavior

We studied both the presence of some carbohydrate compounds in a three-dimensional [3D] matrix harvested from human gingiva and the cell behavior in this matrix. In this experimental research, in order to prepare 3D scaffolds, human palatal gingival biopsies were harvested and physically decellularized by freeze-thawing and sodium dodecyl sulfate [SDS]. The scaffolds were placed within the rings of blastema tissues obtained from a pinna rabbit, in vitro. We evaluated the presence of glycoconjugates and cellular behavior according to histological, histochemical and spectrophotometry techniques at one, two and three weeks after culture. One-way analysis of variance [ANOVA] compared the groups. Extracellular matrix [ECM] remained after decellularization of tissue with 1% SDS. Glycoconjugate contents decreased meaningfully at a higher SDS concentration [p<0.0001]. After culture of the ECM scaffold with blastema, we observed increased staining of alcian blue, periodic acid-Schiff [PAS] and toluidine blue in the scaffold and a number of other migrant cells which was caused by cell penetration into the scaffold. Spectrophotometry results showed an increase in glycosaminoglycans [GAGs] of the decellularized scaffolds at three weeks after culture. The present study has shown that a scaffold generated from palatal gingival tissue ECM is a suitable substrate for blastema cell migration and activity. This scaffold may potentially be useful as a biological scaffold in tissue engineering applications

Effect of curcumin on doxorubicin-induced cytotoxicity in H9c2 cardiomyoblast cells

Doxorubicin [DOX], a widely used chemotherapeutic agent can give rise to serve cardiotoxicity by inducing apoptosis. Curcumin, the active compound of the rhizome of Curcuma longa L. has anti-inflammatory, antioxidant and anti-proliferative activities. Curcumin has been identified to increase cytotoxicity in several cancer cell lines in combination with DOX, but there is no study about its effect and DOX on normal cardiac cells. Therefore, in the present study, we evaluated the effect of curcumin on apoptosis induced by DOX in H9c2 rat heart-derived cells. Cell viability was determined by MTT assay. Also, activation of caspase-3 was evaluated by spectrophotometry. Quantitative real time RT-PCR was used to evaluate the expression of c-IAP1. Detection of intracellular DOX accumulation was performed by flow cytometry. No toxicity observed when the cells exposed for 1 hr to different concentrations of curcumin, but pretreatment of cells with curcumin increased cytotoxicity of DOX in a dose dependent manner. Analysis of caspase-3 activation showed that curcumin pretreatment increased caspase-3 activation. RT-PCR analysis clearly showed that curcumin significantly decreased mRNA gene expression of c-IAP1 compared to cells treated with DOX alone. Pretreatment of H9c2 cells with DOX and curcumin had no effect on the intracellular accumulation of DOX. Our observations indicated that subtoxic concentrations of curcumin sensitize H9c2 cells to DOX-induce apoptosis. These results suggest that the use of curcumin in combination with DOX in malignancy must be reevaluated

Overexpression of BMI1, a polycomb group repressor protein, in bladder tumors: a preliminary report

A polycomb group repressor protein named BMI1 represses the genes that induce cellular senescence and cell death, and it can contribute to cancer when improperly expressed. We aimed to evaluate expression of BMI1 gene in bladder tumors. Tissue specimens containing bladder tumor were evaluated and compared with intact tissues from tumor margins and normal bladder. These were 40 tumor specimens of patients with transitional cell carcinoma of the bladder, 20 tumor-free tissues taken from the margin of the tumors, and 8 specimens from patients without tumor. Specific primers for BMI1 and B2M [as an internal control] were used for reverse transcript polymerase chain reaction technique. The production and distribution of BMI1 protein was also examined by western blotting and immunohistochemistry techniques. Polymerase chain reaction generated a 683-bp product, corresponding to the expect size of BMI1 amplified region. The identity of the amplified fragment was then confirmed by direct DNA sequencing. The mean of expression of BMI1 detected in tumor tissues was significantly higher than that in intact tissues, and there was also a significant association between the mean of gene expression and the stage of malignancy [P<0.001]. The expression of BMI1 at protein level was further confirmed by western blotting and immunohistochemistry. BMI1 is a potent repressor of retinoblastoma and p53 pathways, and hence, elucidating its role in tumorigenesis is very important. We reported for the first time the expression of BMI1 and its correlation with incidence and progress of bladder tumors