Acidic preparations of lysed platelets upregulate proliferative pathways in osteoblast-like cells as demonstrated by genome-wide microarray analysis

Abstract

latelets contain numerous growth factors essential for wound and fracture healing. We investigated the gene expression in human osteoblast-like cells stimulated with lysed platelets prepared in acidic, neutral, or alkaline buffers. Lysed platelets prepared in buffers at pH 5.4, 7.4, and 7.9, were added after neutralization to hFOB 1.19 cells. Genome-wide microarray analysis was performed using the Affymetrix GeneChip 7G Scanner. Biometric, cluster, and pathway analyses were performed with GeneSpring GX. Biometric analyses demonstrated that 53 genes were differentially regulated (p andlt;= 0.005, andgt;= 2-fold increase). Pathway analysis revealed 10 significant pathways of which eight are common ones regulating bone formation and cancer growth. Eleven genes were selected for quantitative real-time polymerase chain reaction (PCR) based on the microarray analysis of the lysed platelets prepared in the pH 5.4 experiments. In conclusion, acidic preparations of lysed platelet concentrates release factors essential for cell proliferation and particularly cell metabolism under hypoxic conditions. The genetic response from these factors was dominated by genes associated with the same pathways observed in bone formation and cancer growth. Activation of TGF-beta in the acidic preparation could be a stimulatory key factor of cell proliferation. These results support the hypothesis that acidification of platelets modifies the stimulatory response of mesenchymal cells in vitro, which is analogous with the observed milieu of a low pH present in wound and fracture sites, as well as in growing tumors.<p>Original Publication: Ola Wahlström, Cecilia Linder, Anna Ansell, Anders Kalén, Mats Söderström and Per Magnusson, Acidic preparations of lysed platelets upregulate proliferative pathways in osteoblast-like cells as demonstrated by genome-wide microarray analysis, 2011, Platelets, (22), 6, 452-460. http://dx.doi.org/10.3109/09537104.2011.565432 Copyright: Informa Healthcare http://informahealthcare.com/</p

Searching for the Molecular Pathways Regulating Bone Mineral Density in the Proteome and RNA Interference Era

“…Furthermore, it provides a panoramic analysis of gene alterations underlying the complex process of bone formation [66]. Therefore, several groups have used microarray to unravel the molecular pathways that regulate osteoblast differentiation and bone formation using a number of cellular models [19,[67][68][69][70][71][72][73][74][75][76][77][78][79][80][81][82][83]. However, it has been reported that the correlation between mRNA and protein abundance in the cell is extremely poor [12,84,85], which is due to transcriptional and translational controls, posttranslational modifications and protein decay.…”