Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800 Penang, Malaysia.
World Premier International Research Initiative‑Institute for Integrated Cell‑Material Sciences (WPI‑iCeMS), Kyoto University, Kyoto 606-8501, Japan.
Mol Med Rep. 2020 Nov;22(5):3645-3658. doi: 10.3892/mmr.2020.11485. Epub 2020 Sep 2.
Eurycoma (E.) longifolia Jack (Tongkat Ali) is a widely applied medicine that has been reported to boost serum testosterone and increase muscle mass. However, its actual biological targets and effects on an in vitro level remain poorly understood. Therefore, the present study aimed to investigate the effects of a standardised E. longifolia extract (F2) on the growth and its associated gene expression profile in mouse Leydig cells. F2, even at lower doses, was found to induce a high level of testosterone by ELISA. The level was as high as the levels induced by eurycomanone and formestane in Leydig cells. However, Leydig cells treated with F2 demonstrated reduced viability, which was likely due to the diminished cell population at the G0/G1 phase and increased cell population arrested at the S phase in the cell cycle, as assessed by MTT assay and flow cytometry, respectively. Cell viability was revived when the treatment time‑point was prolonged to 96 h. Genome‑wide gene analysis by reverse transcription‑quantitative PCR of F2‑treated Leydig cells at 72 h, when the cell growth was not revived, and 96 h, when the cell growth had started to revive, revealed cyclin‑dependent kinase‑like 2 (CDKL2) to be a potential target in regulating the viability of F2‑treated Leydig cells. Functional analysis, as analysed using GeneMANIA Cytoscape program v.3.6.0 (https://genemania.org/), further suggested that CDKL2 could act in concert with Casitas B‑lineage lymphoma and sphingosine kinase 1 interactor‑A‑kinase anchoring protein domain‑containing genes to regulate the viability of F2‑treated Leydig cells. The findings of the present study provide new insights regarding the potential molecular targets associated with the biological effect of E. longifolia extract on cell growth, particularly on the cell cycle, which could aid in enhancing the bioefficacy and reducing the toxicity of this natural product in the future.
育亨宾（E.）长叶杰克（Tongkat Ali）是一种广泛应用的药物，据报道可提高血清睾丸酮水平并增加肌肉质量。然而，其实际的生物学靶点及其在体外水平的作用仍知之甚少。因此，本研究旨在研究标准化育亨宾提取物（F2）对小鼠睾丸间质细胞生长及其相关基因表达谱的影响。通过 ELISA 检测，即使在较低剂量下，F2 也能诱导高水平的睾丸酮。其水平与育亨宾和福美斯坦在睾丸间质细胞中诱导的水平相当。然而，用 F2 处理的睾丸间质细胞显示出降低的活力，这可能是由于细胞周期中 G0/G1 期的细胞群体减少和 S 期的细胞群体增加所致，分别通过 MTT 测定和流式细胞术评估。当处理时间延长至 96 小时时，细胞活力得以恢复。用 F2 处理的睾丸间质细胞在 72 小时（细胞生长未恢复时）和 96 小时（细胞生长开始恢复时）进行全基因组基因分析，通过逆转录定量 PCR 揭示周期蛋白依赖性激酶样 2（CDKL2）可能是调节 F2 处理的睾丸间质细胞活力的潜在靶点。功能分析，如使用 GeneMANIA Cytoscape 程序 v.3.6.0（https://genemania.org/）进行分析，进一步表明 CDKL2 可以与 Casitas B 谱系淋巴瘤和鞘氨醇激酶 1 相互作用蛋白域包含基因协同作用，调节 F2 处理的睾丸间质细胞的活力。本研究的结果提供了有关育亨宾提取物对细胞生长的生物学效应相关潜在分子靶点的新见解，特别是对细胞周期的影响，这有助于在未来提高该天然产物的生物功效并降低其毒性。
