title: Acidic pH conditions mimicking degenerative intervertebral discs impair the survival and biological behavior of human adipose-derived mesenchymal stem cells.
abstract: This study was designed to examine the survival and biological behavior of adipose-derived mesenchymal stem cells (ADMSCs) under an intervertebral disc (IVD)-like acidic environment. Human ADMSCs isolated from two age groups were cultured under four different pH levels (pH 7.4, 7.1, 6.8 and 6.5) which mimicked the standard condition and the normal, mildly degenerated and severely degenerated IVD. Cell viability was measured by fluorescein isothiocyanate-Annexin-V/propidium iodide staining, and cell proliferation was measured by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay. The expression of aggrecan, collagen-I, collagen-II, matrix metalloproteinase-2 (MMP-2), tissue inhibitor of metalloproteinase-3 (TIMP-3), p53 and caspase-3 at the mRNA level was examined by realtime quantitative polymerase chain reaction, and the expression of aggrecan, collagen-I, collagen-II, MMP-2 and TIMP-3 at the protein level was measured by enzyme-linked immunosorbent assay. Acidic pH inhibited the viability and proliferation, and the expression of aggrecan, collagen-I and collagen-II of ADMSCs from both age groups. ADMSCs harvested from young and mature donors exhibited similar responses to the acidic pH, although cells from young donors appeared less sensitive to the low pH levels. The results demonstrated that acidic pH in IVD may be an important deleterious factor for ADMSC-based IVD regeneration. ADMSCs harvested from young donors may be more suitable to be utilized for the implantation into degenerated IVD, and the implantations may be more effective at an early stage of IVD degeneration when the pH of matrix acidity is higher than 6.8.
authors: Department of Orthopedics, 2nd Affiliated Hospital, School of Medicine, Zhejiang University, No. 88 Jie fang Road, Hangzhou 310009,  China.
authors: Hao
authors: H
authors: Li
authors: Chengzhen
authors: C
authors: Liang
authors: Yiqing
authors: Y
authors: Tao
authors: Xiaopeng
authors: X
authors: Zhou
authors: Fangcai
authors: F
authors: Li
authors: Gang
authors: G
authors: Chen
authors: Qi-xin
authors: QX
authors: Chen
mesh_terms: D000143:Acids / Q000378:metabolism; D000273:Adipose Tissue / Q000166:cytology* / Q000201:enzymology / Q000378:metabolism; D001483:Base Sequence; D002470:Cell Survival; D017931:DNA Primers; D004797:Enzyme-Linked Immunosorbent Assay; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D055959:Intervertebral Disc Degeneration / Q000378:metabolism / Q000473:pathology*; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000201:enzymology / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D000143:Acids; D017931:DNA Primers; D016326:Extracellular Matrix Proteins