University of Rome, Italy.
Islets. 2010 Mar-Apr;2(2):96-103. doi: 10.4161/isl.2.2.11170.
Ex vivo islet cell culture in the presence of stimulating factors prior to transplantation is considered a good strategy in contrast to the short conclusion of islets transplantation. Previously, we demonstrated how T3 can increase b-cell function via specific activation of Akt; therefore we hypothesized that thyroid hormone T3 can be considered a promising candidate for the in vitro expansion of islet cell mass. Rat pancreatic islets have been isolated by the collagenase digestion and cultured in the presence or not of the thyroid hormone T3 10⁻⁷ M. Islets viability has been evaluated by the use of two different dyes, one cell-permeable green fluorescent dye and propidium iodide, and by the analysis of core cell damage upcoming. Moreover, islets function has been evaluated by insulin secretion. The ability of b-cells to counteract apoptosis induced by streptozotocin has been analyzed by TUNEL assay. We demonstrated that treatment of primary cultures of rat pancreatic islets with T3 results in augmented β-cell vitality with an increase of their functional properties. In addition, a sensible reduction of the core cell damage has been observed in the T3 treated islets, suggesting the preservation of the β-cells integrity during the culture period. Nonetheless, the insulin secretion is sensibly augmented after T3 stimulation. The strong increment shown in Akt activation suggests the involvement of this pathway in the observed phenomena. In conclusion we indicate T3 as a good factor to improve ex vivo islets cell culture.
在移植前用刺激因子对胰岛细胞进行体外培养被认为是一种很好的策略，与胰岛移植的短期效果形成对比。此前，我们证明了 T3 如何通过特异性激活 Akt 来增加β细胞功能；因此，我们假设甲状腺激素 T3 可以被视为体外扩增胰岛细胞质量的有前途的候选物。大鼠胰岛通过胶原酶消化分离，并在存在或不存在甲状腺激素 T3 10⁻⁷ M 的情况下培养。使用两种不同的染料（一种细胞通透性的绿色荧光染料和碘化丙啶）评估胰岛的活力，并通过分析即将出现的核心细胞损伤。此外，通过胰岛素分泌评估胰岛的功能。通过 TUNEL 测定分析 b 细胞抵抗链脲佐菌素诱导的细胞凋亡的能力。我们证明，用 T3 处理大鼠胰岛原代培养物可增加β细胞活力，并增强其功能特性。此外，在 T3 处理的胰岛中观察到核心细胞损伤明显减少，表明在培养期间β细胞的完整性得到了保持。尽管如此，T3 刺激后胰岛素分泌明显增加。Akt 激活的强烈增加表明该途径参与了观察到的现象。总之，我们表明 T3 是改善胰岛细胞体外培养的一个很好的因素。
