Nuclear Magnetic Resonance Studies of Experimentally Induced Delayed Fracture Union

Newman, Raymond J.; Francis, M. J. O.; Duthie, Robert B.

doi:10.1097/00003086-198703000-00039

Cited by 28 publications

(24 citation statements)

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“…The acid tide of wound healing, i.e., the pH within wounds and fractures, change from acidic to neutral and alkaline pH as the healing process progress (18)(19)(20)(21)(22)(23)(24). The local environment is acidic during the initial stage of healing.…”

Section: Discussionmentioning

confidence: 99%

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Variation of pH in lysed platelet concentrates influence proliferation and alkaline phosphatase activity in human osteoblast-like cells

et al. 2007

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Interestingly, we also found BMP-2 in platelet lysate. However BMP-2 was only present in LPB pH 4.0. We suggest, based on these experimental findings, that acidic milieu influence platelets to release growth factors more potent to stimulate osteoblast proliferation than neutral and alkaline platelet preparations. Lysed platelet concentrates prepared at an alkaline pH might release additional components with stimulating effects pH of platelet concentrate and growth stimulation 4 resulting in other features than cell proliferation. This is the first report, to our knowledge, about the presence of BMP-2 in platelet lysate and about a pH dependent stimulatory effect of lysed platelet concentrates on human osteoblast-like cell proliferation. Lysed platelet concentrates, preincubated in acidic or alkaline buffers, may benefit fracture healing, implant fixation and might also be advantageous in the treatment of wounds with platelet constituents; however, this has to be investigated in extended experimental and clinical settings.pH of platelet concentrate and growth stimulation 5

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Section: Discussionmentioning

confidence: 99%

“…Previously, it has also been described that mineralization and bone repair is pH dependent. The early acidity within fracture hematomas is later followed by a change in pH towards alkalinity (19)(20)(21)(22)(23)(24). A low pH has also been reported during the early phase of wound healing, hence designated the acid tide (25).…”

Section: Introductionmentioning

confidence: 99%

Variation of pH in lysed platelet concentrates influence proliferation and alkaline phosphatase activity in human osteoblast-like cells

et al. 2007

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“…Hence in bone trauma, it is conceivable that intracellular and interstitial fluid pHs in the immediate area of blood supply disruption could have pHs down to 6.4-6.5. Local pH in bone fractures in a rat crush fracture model was determined in vitro to be approximately 7.2 from fluid aspirated from fracture sites 2 days post-fracture [Newman et al, 1987]. However, it is possible that the pH at the fracture site may be even lower a few hours just post-fracture and the collection of fracture site fluid could have resulted in loss of CO 2 thus falsely elevating pH determined by this process.…”

Section: Discussionmentioning

confidence: 99%

“…This results in hypoxic conditions with a shift in cellular metabolism to an anaerobic pathway resulting in the accumulation of lactic acid. Thus, a local acidosis with a low tissue pH can develop at the fracture site [Newman et al, 1985[Newman et al, , 1987]. An early inflammatory response also occurs as the first step in tissue repair after hemostasis has been established.…”

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confidence: 99%

Acidic pH stimulates the production of the angiogenic CXC chemokine, CXCL8 (interleukin‐8), in human adult mesenchymal stem cells via the extracellular signal‐regulated kinase, p38 mitogen‐activated protein kinase, and NF‐κB pathways

Bischoff

Zhu

Makhijani

et al. 2008

J of Cellular Biochemistry

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Blood vessel injury results in limited oxygen tension and diffusion leading to hypoxia, increased anaerobic metabolism, and elevated production of acidic metabolites that cannot be easily removed due to the reduced blood flow. Therefore, an acidic extracellular pH occurs in the local microenvironment of disrupted bone. The potential role of acidic pH and glu-leu-arg (ELR(+)) CXC chemokines in early events in bone repair was studied in human mesenchymal stem cells (hMSCs) treated with medium of decreasing pH (7.4, 7.0, 6.7, and 6.4). The cells showed a reciprocal increase in CXCL8 (interleukin-8, IL-8) mRNA levels as extracellular pH decreased. At pH 6.4, CXCL8 mRNA was induced >60x in comparison to levels at pH 7.4. hMSCs treated with osteogenic medium (OGM) also showed an increase in CXCL8 mRNA with decreasing pH; although, at a lower level than that seen in cells grown in non-OGM. CXCL8 protein was secreted into the medium at all pHs with maximal induction at pH 6.7. Inhibition of the G-protein-coupled receptor alpha, G(alphai), suppressed CXCL8 levels in response to acidic pH; whereas phospholipase C inhibition had no effect on CXCL8. The use of specific mitogen-activated protein kinase (MAPK) signal transduction inhibitors indicated that the pH-dependent increase in CXCL8 mRNA is due to activation of ERK and p38 pathways. The JNK pathway was not involved. NF-kappaB inhibition resulted in a decrease in CXCL8 levels in hMSCs grown in non-OGM. However, OGM-differentiated hMSCs showed an increase in CXCL8 levels when treated with the NF-kappaB inhibitor PDTC, a pyrrolidine derivative of dithiocarbamate.

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“…Some works used 3'P resonance in solution to observe the mechanisms of precipitation of calcium salts either in v i m ( 9 ) or in fracture site ( 10). Compared to the biomedical applications of solution NMR spectroscopy, applications of solid NMR spectroscopy are rather limited.…”

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confidence: 99%

Solid‐State ³¹P NMR Spectroscopy of Bone and Bone Substitutes

Marchandise¹,

Belgrand²,

Legrand³

1992

Magnetic Resonance in Med

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Using magic angle sample spinning 31P NMR spectroscopy, we studied NMR parameters of hydroxyapatite, calcium-deficient hydroxyapatite, and beta-tricalcium phosphate. These data were compared to rabbit bone parameters. Rabbit bone spectrum is similar to deficient hydroxyapatite spectrum but high-power proton decoupling did not modify its linewidth. Moreover, both bone T1 and deficient hydroxyapatite T1 were much longer than pure hydroxyapatite T1 and beta-tricalcium phosphate T1. We used these results to develop quantitative analysis of newly deposited bone inside beta-tricalcium phosphate implants in rabbit. This method made it possible to demonstrate the effect of porosity on osteoinduction of biomaterials.

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Nuclear Magnetic Resonance Studies of Experimentally Induced Delayed Fracture Union

Cited by 28 publications

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Variation of pH in lysed platelet concentrates influence proliferation and alkaline phosphatase activity in human osteoblast-like cells

Variation of pH in lysed platelet concentrates influence proliferation and alkaline phosphatase activity in human osteoblast-like cells

Acidic pH stimulates the production of the angiogenic CXC chemokine, CXCL8 (interleukin‐8), in human adult mesenchymal stem cells via the extracellular signal‐regulated kinase, p38 mitogen‐activated protein kinase, and NF‐κB pathways

Solid‐State ³¹P NMR Spectroscopy of Bone and Bone Substitutes

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Nuclear Magnetic Resonance Studies of Experimentally Induced Delayed Fracture Union

Cited by 28 publications

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Variation of pH in lysed platelet concentrates influence proliferation and alkaline phosphatase activity in human osteoblast-like cells

Variation of pH in lysed platelet concentrates influence proliferation and alkaline phosphatase activity in human osteoblast-like cells

Acidic pH stimulates the production of the angiogenic CXC chemokine, CXCL8 (interleukin‐8), in human adult mesenchymal stem cells via the extracellular signal‐regulated kinase, p38 mitogen‐activated protein kinase, and NF‐κB pathways

Solid‐State 31P NMR Spectroscopy of Bone and Bone Substitutes

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Solid‐State ³¹P NMR Spectroscopy of Bone and Bone Substitutes