Jornal de Toxicologia Clínica
Acesso livre

Abstrato

Alcohol-induced Bone Loss and Quality during Adolescence is Improved by Green Tea Polyphenols

Chwan-Li Shen, Peter J Syapin, Jennifer L Graef, Brenda J Smith, Gordon Brackee, Anna Kate Fowler, Ismael Segura-Ulate, Jia-Sheng Wang and Susan E Bergeson

Our previous studies have shown significant osteo-protective effects of green tea polyphenols (GTP, green tea extract) in various bone loss models. To test the hypothesis that green tea supplementation would protect against binge alcohol-induced deterioration of bone quality in adolescent drinkers, we used a similar approach with green tea supplementation in drinking water. Using a six week, 2 × 3 factorial design of treatment × dose in male Sprague Dawley (SD) adolescent rats, bone parameters [femoral and lumbar vertebrae-4 (LV-4) area (BMA), bone mineral content (BMC), bone mineral density (BMD)], bone turnover biomarkers [serum osteocalcein (OC) and tartrateresistant acid phosphatase-5b (TRAP-5b)] and blood chemistry were measured. The blood chemistry results showed that alcohol administration significantly decreased albumin, glucose, alkaline phosphatase, and amylase levels; increased globulin, phosphorus, creatine kinase, cholesterol, and potassium levels; and had no effect on protein, calcium, blood urea nitrogen, creatinine, aspartate aminotransferase, alanine aminotransferase, sodium, and chloride. GTP supplementation significantly suppressed alkaline phosphatase levels and had no impact on other blood chemistry parameters. Alcohol administration lowered BMA, BMC, and BMD of the femur and LV-4, as well as serum TRAP-5b, but had no impact on serum OC. Supplementation of GTP into the drinking water increased BMD for the femur and BMC for the LV-4. GTP had no effect on scanned BMA or serum OC concentration. There was an interaction between the alcohol administration and GTP dosage in serum TRAP-5b and several parameters of bone strength, which reduced the negative effect on alcohol-induced bone modeling. In summary, our results show that a 6-week binge alcohol administration lowered bone mineral content, density, and strength in femura, reduced proximal tibial trabecular bone volume and lumbar vertebrae, and decreased cortical thickness at the tibial middiaphysis. Supplementation of GTP into the drinking water increased femoral bone mineral density and tibial cortical thickness at the mid-diaphysis. Importantly, GTP supplementation into drinking water improved overall bone quality in young binge-alcohol treated male rats through suppressing bone turnover rate.