Stimulation of bone collagen and non-collagenous protein synthesis by products of 5- and 12-lipoxygenase: determination by use of a simple quantitative assay.
The influence of 5- and 12-lipoxygenase products on the rate of collagen and non-collagenous protein (NCP) synthesis by murine calvarial explants has been investigated using a new assay based on the resistance of native collagen to degradation by pepsin. The reproducibility and simplicity of this assay allows the quantitative estimation of the rate of bone formation in large numbers of cultures. Hydroxyeicosatetraenoic acids (HETEs) stimulated both the rate of collagen and NCP synthesis with maximal stimulation occurring at 10-100 pM. All leukotrienes stimulated collagen synthesis. LTB4, C4 and D4 showed similar dose-responses with maximal activity occurring at 100 pM. LTE4 was less potent only showing activity at 1-10 nM. Only LTD4 demonstrated the capacity to stimulate NCP synthesis with significant stimulation being seen at 10 nM. The extreme sensitivity of bone collagen and NCP synthesis to lipoxygenase products suggests that these mediators may play a physiological role in bone remodelling.
Meghji
S
S
Maxillofacial Surgery and Oral Medicine Research Unit, University of London, Eastman Dental Hospital, UK.
Sandy
J R
JR
Harvey
W
W
Henderson
B
B
Ali
N
N
D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; D000818:Animals; D001842:Bone and Bones / Q000187:drug effects / Q000378:metabolism*; D003094:Collagen / Q000096:biosynthesis* / Q000378:metabolism; D046508:Culture Techniques; D006893:Hydroxyeicosatetraenoic Acids / Q000494:pharmacology*; D007975:Leukotriene B4 / Q000494:pharmacology; D015289:Leukotrienes / Q000494:pharmacology*; D051379:Mice; D008807:Mice, Inbred BALB C; D010281:Parathyroid Hormone / Q000494:pharmacology; D010434:Pepsin A / Q000378:metabolism; D014176:Protein Biosynthesis; D015203:Reproducibility of Results; D013189:SRS-A / Q000494:pharmacology
D006893:Hydroxyeicosatetraenoic Acids; D015289:Leukotrienes; D010281:Parathyroid Hormone; D013189:SRS-A; D007975:Leukotriene B4; C022022:5-hydroxy-6,8,11,14-eicosatetraenoic acid; D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; D003094:Collagen; D010434:Pepsin A