Submitted to: American Society for Bone and Mineral Research
Publication Type: Abstract Only
Publication Acceptance Date: 8/10/2009
Publication Date: 9/5/2009
Citation: Shen, C., Yeh, J., Cao, J.J., Stoecker, B.J., Samathanam, C., Graham, S., Tatum, O., Dagda, R., Tubb, C., Wang, J. 2009. Green Tea Polyphenols and Vitamin D3 Protect Bone Microarchitecture in Female Rats with Chronic Inflammation. American Society for Bone and Mineral Research. 24S1:227. Interpretive Summary:
Technical Abstract: Our recent study showed that green tea polyphenols (GTP) in conjunction with 1-a-OH¬vit-D3 (vitD3) treatment mitigates lipopolysaccharide (LPS)-induced bone mineral density loss in female rats. This study was undertaken to further explore the mechanism and bone microarchitecture of GTP plus vitD3 in rats with chronic inflammation. Forty 3-month-old female rats with LPS implementation (33.3 µg/day) were randomly assigned to a 2 (no GTP vs. 0.5% GTP in drinking water) × 2 (no vitD3 vs. vitD3 at 0.05 µg/kg BW, 5 times per week) factorial design for 12 weeks. Efficacy was evaluated in tibia and femur microarchitecture by histomorphometry and micro-CT, respectively. The strength of bone in femur was assessed by 3-point bending test. Gene expression was determined by real-time RT-PCR. Status of fibrosis in heart vessels was evaluated by trichrome staining. The results of two-way ANOVA show that both GTP and vitD3 treatments independently resulted in a higher values for trabecular bone volume fraction and number in both proximal tibia and femur, but lower values for bone formation rate in cancellous proximal tibia, trabecular separation in proximal tibia and femur, and eroded surface and osteoclast number in endocortical tibial shafts. There is an interaction between GTP and vitD3 in trabecular separation in proximal tibia, trabecular number in femur, and osteoclast number in endocortical tibial shafts. Supplementation GTP in drinking water, not vitD3 treatment, significantly improved the strength of femur, as shown on higher level of yield point force by 3-point bending test. There is a trend of synergistic effect of GTP supplement in conjunction with vitD3 on bone strength (P=0.06). GTP supplementation, not vitD3 treatment, resulted in a lower degree of gene expression of tumor necrosis factor-a in spleen. Neither LPS implementation nor GTP supplementation affected the degree of fibrosis in heart vessels. This study demonstrates that GTP administrated in drinking water plus vitD3 treatment for 12 weeks protect bone microarchitecture from damage due to chronic inflammation. Such a protective role of GTP may, in part, be attributed to a decrease in expression of tumor necrosis factor-alpha. This study may suggest green tea plus vitD3 have a prophylactic role in bone health of women with chronic inflammation.