Koşar Pınar Aslan, Nazıroğlu Mustafa, Övey İshak Suat, Çiğ Bilal
Department of Medical Biology, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey.
Department of Biophysics, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey.
J Membr Biol. 2016 Apr;249(1-2):129-40. doi: 10.1007/s00232-015-9855-0. Epub 2015 Nov 2.
Transient receptor transient receptor potential vanilloid 1 (TRPV1) is a Ca(2+)-permeable channel gated by oxidative stress and capsaicin (CAP) and modulated by melatonin (MEL) and capsazepine (CPZ). A combination of doxorubicin (DOX) and MEL may offer a potential therapy for breast cancer by exerting antitumor and anti-apoptotic effects and modulating Ca(2+) influx and TRPV1 activity. We aimed to investigate the effects of MEL and DOX on the oxidative toxicity of MCF-7 human breast cancer cells, in addition to the activity of the TRPV1 channel and apoptosis. The MCF-7 cells were divided into the following six treatment groups: control, incubated with MEL (0.3 mM), incubated with 0.5 μM DOX, incubated with 1 μM DOX, incubated with MEL + 0.5 μM DOX, or incubated with MEL + 1 μM DOX. The intracellular free Ca(2+) concentration was higher in the DOX groups than in the control, and the concentration was decreased by MEL. The intracellular free Ca(2+) concentration was further increased by treatment with the TRPV1 channel activator CAP (0.01 mM), and it was decreased by the CPZ (0.1 mM). The intracellular production of reactive oxygen species, mitochondrial membrane depolarization, apoptosis level, procaspase 9 and PARP activities, and caspase 3 and caspase 9 activities were higher in the DOX and MEL groups than in the control. Apoptosis and the activity of caspase 9 were further increased in the DOX plus MEL groups. Taken together, the findings indicate that MEL supported the effects of DOX by activation of TRPV1 and apoptosis, as well as by inducing MCF-7 cell death. As the apoptosis and caspase activity of cancer cells increase because of their elevated metabolism, MEL may be useful in supporting their apoptotic capacity.
瞬时受体电位香草酸受体1（TRPV1）是一种Ca（2+）通透性通道，受氧化应激和辣椒素（CAP）门控，并受褪黑素（MEL）和辣椒素拮抗剂（CPZ）调节。阿霉素（DOX）与MEL联合使用可能通过发挥抗肿瘤和抗凋亡作用以及调节Ca（2+）内流和TRPV1活性，为乳腺癌提供一种潜在的治疗方法。我们旨在研究MEL和DOX对MCF-7人乳腺癌细胞氧化毒性的影响，以及TRPV1通道活性和细胞凋亡情况。MCF-7细胞分为以下六个处理组：对照组、用MEL（0.3 mM）孵育、用0.5 μM DOX孵育、用1 μM DOX孵育、用MEL + 0.5 μM DOX孵育或用MEL + 1 μM DOX孵育。DOX组细胞内游离Ca（2+）浓度高于对照组，而MEL可使其降低。用TRPV1通道激活剂CAP（0.01 mM）处理可进一步增加细胞内游离Ca（2+）浓度，而用CPZ（0.1 mM）处理则使其降低。DOX组和MEL组细胞内活性氧生成、线粒体膜去极化、凋亡水平、procaspase 9和PARP活性以及caspase 3和caspase 9活性均高于对照组。DOX加MEL组细胞凋亡和caspase 9活性进一步增加。综上所述，研究结果表明，MEL通过激活TRPV1和诱导细胞凋亡以及诱导MCF-7细胞死亡，增强了DOX的作用。由于癌细胞代谢增强导致其凋亡和caspase活性增加，MEL可能有助于增强其凋亡能力。
