The effects of sustained delivery of growth promoting hormones on the proliferation of MG63 cells in culture.
Bone matrix proteins are being identified in mineralized foci in several different pathological states. Irrespective of how these proteins become localized it is of great interest to further define what endocrine factors are necessary for triggering the release of bone matrix proteins. MG63 cells (Osteosarcoma cell line) were seeded at a density of 1 x 10(5) cells/ml onto two 24 well tissue culture plates. The wells were divided into 8 groups of 6 wells/group. Cells in group 1 were provided with media alone and served as a control. Cells in group II, IV, and VI were supplemented with Insulin Like Growth factor-1 (IGF-1), Testosterone (T), or Growth Hormone (GH), respectively. Cells in groups III, V and VII were supplemented with TCPL capsules containing IGF-1, Test or GH, respectively. Cells in group VIII were incubated with sham TCPL and served as vehicle control. Cells were incubated in the presence or absence of hormones for 24, 48 and 72 hours. At the end of each phase, cell damage, cell morphology, cell number and cellular protein concentrations were determined. The results showed a significant increase in MDA initially in all groups, followed by a drop in MDA levels by the 48-hour phase, and thereafter remaining lower than the control. Results also demonstrated a decrease in total cellular protein following administration of hormones by conventional means. Sustained delivery of the hormones by TCPL resulted in only a slight increase in protein levels. Cell count data showed an initial decrease in all groups, followed by a significant increase in cell number at the end of 48 hours and, finally, reaching control levels at the 72 hour period. Morphological evaluation revealed major structural changes associated with sustained delivery as compared to conventional delivery of hormones. For example, sustained delivery of IGF-1 and T resulted in an increase in mitotic figures, swelling, and aggregate formation. Cluster cellular formation were observed on cells exposed to IGF-1 and T by conventional routes.
Tavassoli
J
J
University of Mississippi Medical Center, Jackson, MS 39206, USA.
Benghuzzi
H
H
Tucci
M
M
D002130:Calcium Phosphates; D002452:Cell Count; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D002516:Ceramics; D016503:Drug Delivery Systems; D013006:Growth Hormone / Q000494:pharmacology*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D008239:Lysine; D008315:Malondialdehyde / Q000032:analysis; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D053495:Osteopontin; D010710:Phosphates; D011506:Proteins / Q000032:analysis; D012795:Sialoglycoproteins / Q000032:analysis; D013739:Testosterone / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D002130:Calcium Phosphates; D010710:Phosphates; D011506:Proteins; C506895:SPP1 protein, human; D012795:Sialoglycoproteins; C112656:tricalcium phosphate lysine; D053495:Osteopontin; D013739:Testosterone; D008315:Malondialdehyde; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone; D008239:Lysine