Roflupram protects against rotenone-induced neurotoxicity and facilitates α-synuclein degradation in Parkinson’s disease models

• Published in: Acta pharmacologica Sinica 2021-12, Vol.42 (12), p.1991-2003
• Main Authors: Dong, Wen-li, Zhong, Jia-hong, Chen, Yun-qing, Xie, Jin-feng, Qin, Yun-yun, Xu, Jiang-ping, Cai, Ning-bo, Li, Meng-fan, Liu, Lu, Wang, Hai-tao
• Format: Article
• Language: English
• Subjects: alpha-Synuclein - metabolism; Animals; Apoptosis; Apoptosis - drug effects; Behavior, Animal - drug effects; Benzene Derivatives - pharmacology; Benzene Derivatives - therapeutic use; Biomedical and Life Sciences; Biomedicine; Cathepsin D; Cathepsin D - metabolism; Cell Line, Tumor; Cell Survival - drug effects; Degradation; Furans - pharmacology; Furans - therapeutic use; Humans; Hydroxylase; Immunology; Internal Medicine; LAMP-1 protein; Lysosomes - drug effects; Male; Medical Microbiology; Membrane proteins; Mice; Mice, Inbred C57BL; Movement - drug effects; Movement disorders; MPP; NAD; NADH; Neurodegenerative diseases; Neuroprotection; Neuroprotective Agents - pharmacology; Neuroprotective Agents - therapeutic use; Neurotoxicity; Parkinson Disease - drug therapy; Parkinson's disease; Pharmacology/Toxicology; Phosphodiesterase 4 Inhibitors - pharmacology; Phosphodiesterase 4 Inhibitors - therapeutic use; Rot; Rotenone; Rotenone - toxicity; SIRT1 protein; Sirtuin 1 - metabolism; Substantia nigra; Synuclein; Tyrosine 3-monooxygenase; Vaccine
• ISSN: 1671-4083; 1745-7254
• DOI: 10.1038/s41401-021-00768-4

We have previously shown that roflupram (ROF) protects against MPP + -induced neuronal damage in models of Parkinson’s disease (PD). Since impaired degradation of α-synuclein (α-syn) is one of the key factors that lead to PD, here we investigated whether and how ROF affects the degradation of α-syn in rotenone (ROT)-induced PD models in vivo and in vitro. We showed that pretreatment with ROF (10 μM) significantly attenuated cell apoptosis and reduced the level of α-syn in ROT-treated SH-SY5Y cells. Furthermore, ROF significantly enhanced the lysosomal function, as evidenced by the increased levels of mature cathepsin D (CTSD) and lysosomal-associated membrane protein 1 (LAMP1) through increasing NAD + /NADH and the expression of sirtuin 1 (SIRT1). Pretreatment with an SIRT1 inhibitor selisistat (SELI, 10 μM) attenuated the neuroprotection of ROF, ROF-reduced expression of α-syn, and ROF-increased expression levels of LAMP1 and mature CTSD. Moreover, inhibition of CTSD by pepstatin A (20 μM) attenuated ROF-reduced expression of α-syn. In vivo study was conducted in mice exposed to ROT (10 mg·kg −1 ·d −1 , i.g.) for 6 weeks; then, ROT-treated mice received ROF (0.5, 1, or 2 mg·kg −1 ·d −1 ; i.g.) for four weeks. ROF significantly ameliorated motor deficits, which was accompanied by increased expression levels of tyrosine hydroxylase, SIRT1, mature CTSD, and LAMP1, and a reduced level of α-syn in the substantia nigra pars compacta. Taken together, these results demonstrate that ROF exerts a neuroprotective action and reduces the α-syn level in PD models. The mechanisms underlying ROF neuroprotective effects appear to be associated with NAD + /SIRT1-dependent activation of lysosomal function.