(-)-Epigallocatechin Gallate Reduces Platelet-Derived Growth Factor-BB-Stimulated Interleukin-6 Synthesis in Osteoblasts: Suppression of SAPK/JNK
Figure 1
Effect of EGCG on the PDGF-BB-stimulated
IL-6 synthesis and expression levels of IL-6 mRNA in osteoblasts. (a)
Osteoblast-like MC3T3-E1 cells were pretreated with various doses of EGCG for
60 minutes, and then stimulated by 50 ng/mL PDGF-BB or vehicle for 24 hours.
Each value represents the meanSEM of triplicate determinations.
Similar results were obtained with two additional and different cell
preparations. : compared to the value of
control. : compared to the value of
PDGF-BB alone. (b) Primary cultures of osteoblast were pretreated with or
without 30 μM of EGCG for 60 minutes, and then stimulated
by 50 ng/mL PDGF-BB or vehicle for 24 hours. Each value represents the meanSEM of triplicate determinations. Similar results were obtained with two
additional and different cell preparations. : compared to value of the
PDGF-BB alone. (c) Osteoblast-like MC3T3-E1 cells were
pretreated with 30 μM EGCG or vehicle for 60 minutes, and then
stimulated by 50
ng/mL PDGF-BB for 60 minutes. Total RNA was isolated and
transcribed into complementary DNA. The expressions of IL-6 mRNA and GAPDH mRNA
were quantified by real-time RT-PCR. IL-6 mRNA levels were normalized with
those of GAPDH mRNA. Results were standardized for the value of control
(without EGCG and PDGF-BB). Each value represents the meanSEM of triplicate
determinations. Similar results were
obtained with two additional and different cell preparations. : compared to the value of
control. : compared to the value of
PDGF-BB alone.
