背景:绝大多数线粒体疾病将临床治疗局限于姑息治疗。雷帕霉素已成为线粒体疾病的潜在治疗药物,因为它已在一些线粒体疾病的小鼠模型中显示出治疗益处。然而,潜在的治疗机制尚不清楚,需要确定最小有效剂量,目前尚不清楚这种疗法是否可以普遍使用.
方法:我们已经评估了低剂量和高剂量的雷帕霉素给药是否可以在CoQ缺乏导致的线粒体脑病的小鼠模型(Coq9R239X)中产生治疗效果。评估涉及表型,分子,图像(组织病理学和MRI),代谢组学,转录组学和生物能量学分析。
结果:低剂量雷帕霉素诱导肝脏代谢变化和中脑转录组学修饰。由于mTORC1的普遍抑制,高剂量的雷帕霉素在中脑中诱导转录组学谱的进一步改变。然而,无论是低剂量还是高剂量的雷帕霉素都无法改善线粒体生物能学,Coq9R239X小鼠的脑损伤和表型特征,导致缺乏提高生存率的功效。
结论:这些结果可能是由于缺乏小胶质细胞增生源性神经炎症,诱导自噬的局限性,或者需要功能性的CoQ结。因此,将雷帕霉素疗法转化为线粒体疾病患者的临床需要,至少,考虑每种线粒体疾病的特殊性。FUND:Supportedbythegrantsfrom\"FundaciónIsabelGemio-FederaciónEspañoladeEnfermedadesNeuromusculares-FederaciónFEDER\"(TSR-1),NIH(P01HD080642)和ERC(Stg-337327)。
BACKGROUND: The vast majority of mitochondrial disorders have limited the clinical management to palliative care. Rapamycin has emerged as a potential therapeutic drug for mitochondrial diseases since it has shown therapeutic benefits in a few mouse models of mitochondrial disorders. However, the underlying therapeutic mechanism is unclear, the minimal effective dose needs to be defined and whether this therapy can be generally used is unknown.
METHODS: We have evaluated whether low and high doses of rapamycin administration may result in therapeutic effects in a mouse model (Coq9R239X) of mitochondrial encephalopathy due to CoQ deficiency. The evaluation involved phenotypic, molecular, image (histopathology and MRI), metabolomics, transcriptomics and bioenergetics analyses.
RESULTS: Low dose of rapamycin induces metabolic changes in liver and transcriptomics modifications in midbrain. The high dose of rapamycin induces further changes in the transcriptomics profile in midbrain due to the general inhibition of mTORC1. However, neither low nor high dose of rapamycin were able to improve the mitochondrial bioenergetics, the brain injuries and the phenotypic characteristics of Coq9R239X mice, resulting in the lack of efficacy for increasing the survival.
CONCLUSIONS: These results may be due to the lack of microgliosis-derived neuroinflammation, the limitation to induce autophagy, or the need of a functional CoQ-junction. Therefore, the translation of rapamycin therapy into the clinic for patients with mitochondrial disorders requires, at least, the consideration of the particularities of each mitochondrial disease. FUND: Supported by the grants from \"Fundación Isabel Gemio - Federación Española de Enfermedades Neuromusculares - Federación FEDER\" (TSR-1), the NIH (P01HD080642) and the ERC (Stg-337327).