Institute of Metabolism and Endocrinology, the Second Xiang-Ya Hospital, Central South University, Changsha, China.
Acta Pharmacol Sin. 2010 Mar;31(3):289-96. doi: 10.1038/aps.2009.206. Epub 2010 Feb 15.
To investigate the synergistic action of L-carnitine (LC) and taurine (TAU) on the proliferation and osteoblastic differentiation of vascular smooth muscle cells (VSMCs).
DNA and protein synthesis of VSMCs were assessed using scintillation counting. Alkaline phosphatase (ALP) activity and calcium content were determined to investigate the effects of LC and TAU on the osteoblastic differentiation and mineralization of VSMCs. TAU uptake by VSMCs was assayed. RNA interference was used to down-regulate the expression of the TAU transporter (TAUT) in rat VSMCs.
LC and TAU synergistically inhibited the proliferation and beta-glycerophosphate (beta-GP)-induced osteoblastic differentiation of VSMCs as evidenced by the decreased [(3)H]thymidine incorporation, ALP activity and calcium deposition. Furthermore, LC stimulated the TAU uptake and TAUT expression in VSMCs. Suppression of TAUT with short hairpin RNA (shRNA) abolished the synergistic action of LC and TAU in VSMCs.
The synergistic inhibitory action of LC and TAU on the proliferation and osteoblastic differentiation of VSMCs is attributable to the up-regulation of TAUT expression and TAU uptake by LC.
研究左旋肉碱（LC）和牛磺酸（TAU）对血管平滑肌细胞（VSMCs）增殖和成骨分化的协同作用。
使用闪烁计数法评估 VSMCs 的 DNA 和蛋白质合成。测定碱性磷酸酶（ALP）活性和钙含量，以研究 LC 和 TAU 对 VSMCs 成骨分化和矿化的影响。测定 VSMCs 对 TAU 的摄取。采用 RNA 干扰技术下调大鼠 VSMCs 中 TAU 转运体（TAUT）的表达。
LC 和 TAU 协同抑制 VSMCs 的增殖和β-甘油磷酸（β-GP）诱导的成骨分化，表现为[(3)H]胸苷掺入、ALP 活性和钙沉积减少。此外，LC 刺激 VSMCs 摄取 TAU 和 TAUT 表达。短发夹 RNA（shRNA）抑制 TAUT 可消除 LC 和 TAU 在 VSMCs 中的协同作用。
LC 和 TAU 对 VSMCs 增殖和成骨分化的协同抑制作用归因于 LC 上调 TAUT 表达和 TAU 摄取。
