Quantitative immunodetection of key elements of polyphosphoinositide signal transduction in osteoblasts from arthritic patients shows a direct correlation with cell proliferation.
Phosphoinositides play an essential role in diverse cellular functions such as cell proliferation, cytoskeletal regulation, intracellular vesicle trafficking, motility, cell metabolism and death. Alteration of these pathways is common to many diseases. In this study, we show that osteoblasts from patients affected by osteoarthritis (OA) and by rheumatoid arthritis (RA) present a decreased cell proliferation and a reduced expression of the key elements of polyphosphoinositide signal transduction such as phosphatidylinositol-3-kinase (PI 3K), phospholipase C gamma1 (PLCgamma1), and protein kinase C zeta (PKCzeta) compared to the post-traumatic (PT) patients. Our results suggest that a correlation may exist between the reduced osteoblast proliferation observed in OA and RA patients and the lowered expression of PI 3K, PLCgamma1, and PKCzeta enzymes. The reduced proliferation rate of osteoblasts in response to these signal transduction effectors could counteract the evolution of arthritic disease.
Zini
Nicoletta
N
ITOI--CNR, Sezione di Bologna c/o IOR, via di Barbiano 1/10, 40136 Bologna, Italy. n_zini@area.bo.cnr.it
Lisignoli
Gina
G
Solimando
Liliana
L
Bavelloni
Alberto
A
Valmori
Aurelio
A
Cristino
Sandra
S
Martelli
Alberto Maria
AM
Facchini
Andrea
A
Maraldi
Nadir Mario
NM
D000368:Aged; D001172:Arthritis, Rheumatoid / Q000201:enzymology* / Q000473:pathology; D015415:Biomarkers / Q000378:metabolism; D049109:Cell Proliferation; D002478:Cells, Cultured; D005260:Female; D005270:Femur Head / Q000166:cytology; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000201:enzymology* / Q000473:pathology; D010006:Osteoblasts / Q000378:metabolism* / Q000473:pathology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D018129:Phosphatidylinositol Phosphates / Q000378:metabolism*; D051966:Phospholipase C gamma; D011493:Protein Kinase C / Q000378:metabolism; D015398:Signal Transduction; D010738:Type C Phospholipases / Q000378:metabolism; D014947:Wounds and Injuries / Q000378:metabolism / Q000473:pathology; D000099221:Protein Kinase C zeta
D015415:Biomarkers; D019869:Phosphatidylinositol 3-Kinases; D018129:Phosphatidylinositol Phosphates; D051966:Phospholipase C gamma; D011493:Protein Kinase C; D010738:Type C Phospholipases; D000099221:Protein Kinase C zeta