SCFAs influence the individual stages of fracture healing and the different cell types involved. Histone modifications, mainly mediated by HDAC inhibition, and GPR-signalling are the main molecular mechanisms mediating the effects of SCFAs. Abbreviations: SCFAs = Short-chain fatty acids, HDAC = Histone deacetylase, GPR = G protein-coupled receptor, M2= macrophage-phenotype 2, TNFα = Tumour necrosis factor α, IL-10 = Interleukin 10, TGF-β = Transforming growth factor β, H3K9 = Histone 3 Lysine 9, t-PA = tissue plasminogen activator, VEGF = vascular endothelial growth factor, PECAM1 = platelet and endothelial cell adhesion molecule 1, PPARγ = Peroxisome proliferator-activated receptor γ, ApoE-KO = Apolipoprotein E knock-out, eNOS = endothelial nitric oxide synthase, HUVECs = human umbilical vein endothelial cells, mTORC1 = mammalian target of rapamycin complex 1, MMP = matrix metalloproteinase, Sox9 = sex determining region Y box 9, Runx2 = Runt-related transcription factor 2, COL2A1 = collagen type 2 alpha 1 chain, sPG = sulphated proteoglycan, MSC = mesenchymal stromal cell, ALP = alkaline phosphatase, OPG = osteoprotegerin, RANKL = receptor activator of NF-κB ligand. Figure created with
BioRender.com.