Experimental Study Of Chinese Nutgall Water Extract Inhibiting The Toxic Effect Of Lipopolysacchride On Human Dental Cells

Pulpitis is an infectious disease which is caused mainly by gram-neotology bacterium. It's also a common disease for stomatology outpatient service. LPS locking on the outer film of gram-neogative bacteria is a main toxic factor, and it can cause pulpal inflammation and poison HDPCs. HDPCs are dominating cells in dental pulpal tissue. HDPCs can not only synthesize dental pulp organic ingredient, but also differentiate into odontoblast and protect dental pulp. LPS can affect HDPCs by two ways. Direct effects: LPS can inhibit proliferation and differentiation of HDPCs, damage the ultrastucture of HDPCs, stimulate HDPCs to sectete cell factors. Indirect effects:LPS can stimulate immunity cells to secrete cell factors, which affect HDPCs conversely. Therefore, it is important to inhibit the toxic effect of LPS to HDPCs. Chinese nutgall has some special characters, such as anti-bactera, anti-virus, anti-oxidation and constringency. It can break down LPS and block its biological functions.To evaluate the influence of Chinese nutgall water extract on the toxic effect of LPS to HDPCs, MTT method was used to examine the influence of Chinese nutgall extract on the inhibitory effect of LPS to HDPCs'proliferation, TEM was used to examine the effect of Chinese nutgall extract on the damage of HDPCs'ultrastructure by LPS, a modified enzyme dynamical method was used to examine the influence of Chinese nutgall extract on the inhibitory effect of LPS to HDPCs'ALP activity, radioimmunoussary(RIA) was used to examine the effect of Chinese nutgall extract on the production of IL-6 from HDPCs stimulated by LPS. Experiment 1. Chinese nutgall water extract's influence on the inhibitory effect of LPS to HDPCs'proliferation.The MTT method was applied to analyze cells'proliferation. The results indicated that HDPCs'proliferation was inhibited significantly when they were cultured in DMEM with 50,100μg/mlLPS. Low-dose of Chinese nutgall water extracts( 1.25,2.5,5μg/ml) resisted the inhibitory effect of LPS to HDPCs'proliferation significantly .From the third day , the proliferation activity of HDPCs incubated with 2.5μg/ml Chinese nutgall water extract and LPS increased signicificantly in a time-dependent manner. So we concluded that low-dose Chinese nutgall water extract resisted the inhibitory effect of LPS to HDPCs'proliferation .Experiment 2. Chinese nutgall water extract's influence on the damage effect of LPS to HDPCs'ultrastructure.The transmission electron microscope(TEM)method was applied to observe cells'ultrastructure. The results indicated that 100μg/ml LPS had significant damage on the ultrastructure of HDPCs . After 5μg/ml Chinese nutgall water extract were added , the damage of HDPCs'ultrastructure was decreased significantly. So we concluded that Low-dose Chinese nutgall extract resisted the damage effect of LPS to HDPCs'ultrastructure. Experiment 3. Chinese nutgall water extract's influence on the inhibitory effect of LPS to ALP activity of HDPCs.The modified enzyme dynamical method was used to analyze cells'ALP activity. The results indicated that low-dose of Chinese nutgall water extract(2.5,5,10μg/ml)resisted the inhibitory effect of LPS to HDPCs'ALP activity significantly . From the second day , the ALP activity of HDPCs incubated with 5μg/ml Chinese nutgall water extract and LPS increased signicificantly in a time-dependent manner. So we concluded that low-dose Chinese nutgall water extract resisted the inhibitory effect of LPS to ALP activity of HDPCs.Experiment 4. Chinese nutgall water extract's influence on the production of IL-6 from HDPCs stimulated by LPS.The radioimmunoussary method was applied to analyze the activity of IL-6 from HDPCs. The results indicated that the amount of IL-6 from HDPCs stimulated by 100μg/ml LPS significantly decreased by 2.5,5,10,20μg/ml Chinese nutgall water extract in a dose-depent manner. So we concluded that Chinese nutgall water extract inhibited the production of IL-6 from HDPCs stimulated by LPS.