Brito Vanessa, Marques Mariana, Esteves Marta, Serra-Almeida Catarina, Alves Gilberto, Almeida Paulo, Bernardino Liliana, Silvestre Samuel
CICS-UBI-Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal.
Centre for Neurosciences and Cell Biology (CNC), University of Coimbra, 3004-517 Coimbra, Portugal.
Biomedicines. 2023 Mar 7;11(3):812. doi: 10.3390/biomedicines11030812.
Steroids constitute an important class of pharmacologically active molecules, playing key roles in human physiology. Within this group, 16-arylideneandrostane derivatives have been reported as potent anti-cancer agents for the treatment of leukemia, breast and prostate cancers, and brain tumors. Additionally, 5α,6α-epoxycholesterol is an oxysterol with several biological activities, including regulation of cell proliferation and cholesterol homeostasis. Interestingly, pregnenolone derivatives combining these two modifications were described as potential neuroprotective agents. In this research, novel 16-arylidene-5α,6α-epoxyepiandrosterone derivatives were synthesized from dehydroepiandrosterone by aldol condensation with different aldehydes followed by a diastereoselective 5α,6α-epoxidation. Their cytotoxicity was evaluated on tumoral and non-tumoral cell lines by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Furthermore, the assessment of the neuroprotective activity of these derivatives was performed in a dopaminergic neuronal cell line (N27), at basal conditions, and in the presence of the neurotoxin 6-hydroxydopamine (6-OHDA). Interestingly, some of these steroids had selective cytotoxic effects in tumoral cell lines, with an IC of 3.47 µM for the 2,3-dichlorophenyl derivative in the breast cancer cell line (MCF-7). The effects of this functionalized epoxide on cell proliferation (Ki67 staining), cell necrosis (propidium iodide staining), as well as the analysis of the nuclear area and near neighbor distance in MCF-7 cells, were analyzed. From this set of biological studies, strong evidence of the activation of apoptosis was found. In contrast, no significant neuroprotection against 6-OHDA-induced neurotoxicity was observed for the less cytotoxic steroids in N27 cells. Lastly, molecular docking simulations were achieved to verify the potential affinity of these compounds against important targets of steroidal drugs (androgen receptor, estrogen receptor α, and 5α-reductase type 2, 17α-hydroxylase-17,20-lyase and aromatase enzymes). This in silico study predicted a strong affinity between most novel steroidal derivatives and 5α-reductase and 17α-hydroxylase-17,20-lyase enzymes.
类固醇是一类重要的具有药理活性的分子，在人体生理过程中发挥着关键作用。在这一类化合物中，16-亚芳基雄甾烷衍生物已被报道为治疗白血病、乳腺癌、前列腺癌和脑肿瘤的有效抗癌药物。此外，5α,6α-环氧胆固醇是一种具有多种生物活性的氧甾醇，包括调节细胞增殖和胆固醇稳态。有趣的是，结合这两种修饰的孕烯醇酮衍生物被描述为潜在的神经保护剂。在本研究中，以脱氢表雄酮为原料，通过与不同醛进行羟醛缩合，然后进行非对映选择性5α,6α-环氧化反应，合成了新型16-亚芳基-5α,6α-环氧表雄酮衍生物。通过3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐法在肿瘤细胞系和非肿瘤细胞系上评估了它们的细胞毒性。此外，在多巴胺能神经元细胞系（N27）中，在基础条件下以及在存在神经毒素6-羟基多巴胺（6-OHDA）的情况下，对这些衍生物的神经保护活性进行了评估。有趣的是，其中一些类固醇在肿瘤细胞系中具有选择性细胞毒性作用，2,3-二氯苯基衍生物在乳腺癌细胞系（MCF-7）中的IC50为3.47 μM。分析了这种功能化环氧化物对MCF-7细胞增殖（Ki67染色）、细胞坏死（碘化丙啶染色）以及细胞核面积和近邻距离的影响。从这一系列生物学研究中，发现了细胞凋亡激活的有力证据。相比之下，在N27细胞中，细胞毒性较小的类固醇对6-OHDA诱导的神经毒性没有明显的神经保护作用。最后，进行了分子对接模拟，以验证这些化合物对甾体药物重要靶点（雄激素受体、雌激素受体α以及2型5α-还原酶、17α-羟化酶-17,20-裂解酶和芳香化酶）的潜在亲和力。这项计算机模拟研究预测，大多数新型甾体衍生物与5α-还原酶和17α-羟化酶-17,20-裂解酶之间具有很强的亲和力。
