title: In situ fatty acid profile of femoral cancellous subchondral bone in osteoarthritic and fragility fracture females: implications for bone remodelling.
abstract: We report here differences in the fatty acid profile of cancellous bone matrix, including n-3, n-6, mono- and poly-unsaturated, as well as saturated fats, between femoral heads from female OA (n=8, aged 68-88years), fractured neck of femur (#NOF) (n=19, 67-88years) and autopsy controls (CTRL) (n=4, 85-97years). Femoral heads were collected from individuals undergoing orthopaedic surgery for OA or #NOF; the fatty acid profile of sub-samples from the superior principal compressive and superior principal tensile regions were determined by gas chromatography. A total of 42 individual fatty acids were detected at varying concentrations with significant differences between subchondral bone from OA subjects, subchondral bone from #NOF subjects and subchondral bone from CTRL subjects, as well as between the superior principal compressive and superior principal tensile regions (for saturated fats only). Subchondral bone from OA subjects had higher total n-6 (OA=10.89±3.17, #NOF=11.11±1.83, CTRL=8.32±2.05, p=0.008) and total n-3 (OA=1.34±0.38, #NOF=1.19±0.18, CTRL=1.15±0.48, p=0.011) percentages than subchondral bone from #NOF subjects and subchondral bone from CTRL subjects, and there was no difference in the n-6:n-3 ratio, nor within the percentage of n-9 fatty acids. Arachidonic acid (OA=0.42±0.16, #NOF=0.26±0.06, CTRL=0.28±0.06, p=0.01), and γ-linolenic acid (OA=0.11±0.03, #NOF=0.05±0.02, CTRL=0.04±0.02, p<0.001) were higher in subchondral bone from OA subjects than subchondral bone from #NOF subjects and subchondral bone from CTRL subjects. In conclusion, there is a wide diversity of fatty acids in cancellous bone matrix from the femoral heads of OA and #NOF, suggesting they may have regulatory effects on inflammatory processes, and their metabolites. This article is part of a Special Issue entitled "Osteoarthritis".
authors.affiliation: Bone and Joint Research Laboratory, Directorate of Surgical Pathology, SA Pathology (IMVS) and Hanson Institute, PO Box 14 Rundle Mall, Adelaide, SA, 5000, Australia. julia.humphries@health.sa.gov.au
authors.forename: J M
authors.initials: JM
authors.lastname: Humphries
authors.forename: J S
authors.initials: JS
authors.lastname: Kuliwaba
authors.forename: R J
authors.initials: RJ
authors.lastname: Gibson
authors.forename: N L
authors.initials: NL
authors.lastname: Fazzalari
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016723:Bone Remodeling / Q000502:physiology*; D016022:Case-Control Studies; D019245:Compressive Strength; D005227:Fatty Acids / Q000378:metabolism*; D005260:Female; D005265:Femoral Neck Fractures / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology*; D005269:Femur / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology* / Q000503:physiopathology; D005270:Femur Head / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008875:Middle Aged; D010003:Osteoarthritis / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology*; D011859:Radiography; D013718:Tensile Strength
chemical_list: D005227:Fatty Acids