BACKGROUND: Hyaluronan is a major component of the extracellular matrix of periodontal ligament (PDL) contributing to the structural and functional integrity. Hyaluronans contribute to the buffering effect of the PDL during chewing, and they are also important in inflammation and wound healing. Hyaluronan is known to be synthesized and turned over by the resident PDL cells, although the mechanisms of hyaluronan metabolism still remain unclear. Hyaluronidase (HAase), an endoglycosidase, degrades hyaluronan into small fragments. Currently, 3 human HAases, HYAL1, HYAL2, and PH-20, have been identified and well characterized. METHODS: This study was conducted to investigate the expression and activity of these HAases in cultured human PDL fibroblasts and to elucidate the mechanisms involved in hyaluronan metabolism under normal and inflammatory conditions. Human PDL fibroblasts derived from the periodontium of 3 premolars were cultured with or without interleukin (IL)-1beta (0.1 to 10 ng/ml) and tumor necrosis factor (TNF)-alpha (1 to 100 ng/ml) for 0 to 48 hours. The expression of HAase mRNA was assessed by reverse transcription-polymerase chain reaction (RT-PCR) and quantitative real-time PCR, and the enzymatic activity was examined using hyaluronan zymography. RESULTS: PDL fibroblasts expressed HYAL1 and HYAL2 mRNAs, but not PH-20 mRNA. The expression of HYAL1 mRNA was enhanced by about 3.5- and 3.7-fold at maximum after 1-hour stimulation with 1 ng/ml IL-1beta and after 3-hour stimulation with 10 ng/ml TNF-alpha, respectively. The expression of HYAL2 and PH-20 mRNAs was not affected by stimulation with cytokines. HAase activity was detected in conditioned medium from PDL fibroblast cultures, and the activity was enhanced by treatment with 10 ng/ml TNF-alpha. CONCLUSION: These results suggest that PDL fibroblasts express HAases and generate HAase activity essential for extracellular hyaluronan metabolism under physiological and inflammatory conditions.
BACKGROUND:Hyaluronan is a major component of the extracellular matrix of periodontal ligament (PDL) contributing to the structural and functional integrity. Hyaluronans contribute to the buffering effect of the PDL during chewing, and they are also important in inflammation and wound healing. Hyaluronan is known to be synthesized and turned over by the resident PDL cells, although the mechanisms of hyaluronan metabolism still remain unclear. Hyaluronidase (HAase), an endoglycosidase, degrades hyaluronan into small fragments. Currently, 3 humanHAases, HYAL1, HYAL2, and PH-20, have been identified and well characterized. METHODS: This study was conducted to investigate the expression and activity of these HAases in cultured human PDL fibroblasts and to elucidate the mechanisms involved in hyaluronan metabolism under normal and inflammatory conditions. Human PDL fibroblasts derived from the periodontium of 3 premolars were cultured with or without interleukin (IL)-1beta (0.1 to 10 ng/ml) and tumor necrosis factor (TNF)-alpha (1 to 100 ng/ml) for 0 to 48 hours. The expression of HAase mRNA was assessed by reverse transcription-polymerase chain reaction (RT-PCR) and quantitative real-time PCR, and the enzymatic activity was examined using hyaluronan zymography. RESULTS: PDL fibroblasts expressed HYAL1 and HYAL2 mRNAs, but not PH-20 mRNA. The expression of HYAL1 mRNA was enhanced by about 3.5- and 3.7-fold at maximum after 1-hour stimulation with 1 ng/ml IL-1beta and after 3-hour stimulation with 10 ng/ml TNF-alpha, respectively. The expression of HYAL2 and PH-20 mRNAs was not affected by stimulation with cytokines. HAase activity was detected in conditioned medium from PDL fibroblast cultures, and the activity was enhanced by treatment with 10 ng/ml TNF-alpha. CONCLUSION: These results suggest that PDL fibroblasts express HAases and generate HAase activity essential for extracellular hyaluronan metabolism under physiological and inflammatory conditions.
Authors: Andrea Mueller; Masako Fujioka-Kobayashi; Heinz-Dieter Mueller; Adrian Lussi; Anton Sculean; Patrick R Schmidlin; Richard J Miron Journal: Clin Oral Investig Date: 2016-05-19 Impact factor: 3.573
Authors: Vinata B Lokeshwar; Pablo Gomez; Mario Kramer; Judith Knapp; Melissa A McCornack; Luis E Lopez; Nevis Fregien; Neetika Dhir; Steve Scherer; David J Klumpp; Murugesan Manoharan; Mark S Soloway; Bal L Lokeshwar Journal: J Biol Chem Date: 2008-08-21 Impact factor: 5.157