Krueger Gabriel Francisco, de Oliveira Milene Castilhos, Gassen Humberto Thomazi, Sganzerla Juliana Tomaz, Simon Daniel, Grivicich Ivana, Hernández Pedro Antonio González, Miguens-Jr Sergio Augusto Quevedo
Department of Oral Medicine, Graduate Program in Dentistry, Universidade Luterana do Brasil, Canoas, RS, Brazil.
Graduate Program in Cellular and Molecular Biology Applied to Health, Universidade Luterana do Brasil, Canoas, RS, Brazil.
J Lasers Med Sci. 2020 Summer;11(3):262-267. doi: 10.34172/jlms.2020.44. Epub 2020 Jun 21.
This experimental study investigated the mRNA expression of aquaporins (AQPs) 1 and 5 in the parotid glands of rats irradiated with volumetric modulated arc therapy (VMAT) and subjected to low-level laser therapy (LLLT) at different time points. The sample consisted of 30 Wistar rats (Rattus norvegicus) divided into the following groups: control, LLLT alone (LG), radiotherapy alone (RG), and experimental groups that received LLLT at 24 hours (early experimental group [EEG], n=12) and 120 hours (late experimental group [LEG], n=12) after radiotherapy. VMAT was delivered at a single dose (12 Gy) and LLLT was performed with an aluminium-gallium-arsenide diode laser (660 nm, 100 mW), spot area of 0.0028 cm2, energy of 2 J/cm applied to 3 spots in the region corresponding to the right parotid gland, for 10 consecutive days. The right parotid gland was resected and prepared for RNA extraction. The gene expression of AQPs was evaluated by quantitative polymerase chain reaction (qPCR) using specific TaqMan probes, with the HPRT gene as an internal control. The lowest AQP1 gene expression was 0.83 (0.27) with the use of LLLT 24 hours after radiotherapy (EEG), and the highest was 1.56 (0.80) with the use of LLLT alone (LG). Likewise, the lowest AQP5 gene expression was found in the EEG (mean = 0.88; SD = 0.49) and the highest in the LG (mean = 1.29; SD = 0.33). The use of LLLT after radiotherapy may contribute to the maintenance and an increase of these proteins, even when used at a later time point after radiotherapy.
本实验研究调查了接受容积调强弧形放疗（VMAT）并在不同时间点接受低强度激光治疗（LLLT）的大鼠腮腺中 aquaporins（AQPs）1 和 5 的 mRNA 表达。样本由 30 只 Wistar 大鼠（褐家鼠）组成，分为以下几组：对照组、单纯 LLLT 组（LG）、单纯放疗组（RG），以及放疗后 24 小时接受 LLLT 的实验组（早期实验组[EEG]，n = 12）和放疗后 120 小时接受 LLLT 的实验组（晚期实验组[LEG]，n = 12）。VMAT 以单次剂量（12 Gy）进行，LLLT 使用铝镓砷二极管激光器（660 nm，100 mW），光斑面积为 0.0028 cm²，能量为 2 J/cm，应用于右侧腮腺对应的区域的 3 个光斑，连续照射 10 天。切除右侧腮腺并准备进行 RNA 提取。使用特异性 TaqMan 探针通过定量聚合酶链反应（qPCR）评估 AQPs 的基因表达，以 HPRT 基因作为内对照。放疗后 24 小时使用 LLLT 时，AQP1 基因表达最低为 0.83（0.27），单纯使用 LLLT 时最高为 1.56（0.80）。同样，EEG 组中 AQP5 基因表达最低（平均值 = 0.88；标准差 = 0.49），LG 组中最高（平均值 = 1.29；标准差 = 0.33）。放疗后使用 LLLT 可能有助于这些蛋白质的维持和增加，即使在放疗后的较晚时间点使用也是如此。
