Juarez-Flores 2018 J Transl Med
|Juárez-Flores DL, González-Casacuberta I, Ezquerra M, Bañó M, Carmona-Pontaque F, Catalán-García M, Guitart-Mampel M, Rivero JJ, Tobias E, Milisenda JC, Tolosa E, Marti MJ, Fernández-Santiago R, Cardellach F, Morén C, Garrabou G (2018) Exhaustion of mitochondrial and autophagic reserve may contribute to the development of LRRK2G2019S -Parkinson's disease. J Transl Med 16:160.|
Juarez-Flores DL, Gonzalez-Casacuberta I, Ezquerra M, Bano M, Carmona-Pontaque F, Catalan-Garcia M, Guitart-Mampel M, Rivero JJ, Tobias E, Milisenda JC, Tolosa E, Marti MJ, Fernandez-Santiago R, Cardellach F, Moren C, Garrabou G (2018) J Transl Med
Abstract: Mutations in leucine rich repeat kinase 2 (LRRK2) are the most common cause of familial Parkinson's disease (PD). Mitochondrial and autophagic dysfunction has been described as etiologic factors in different experimental models of PD. We aimed to study the role of mitochondria and autophagy in LRRK2G2019S -mutation, and its relationship with the presence of PD-symptoms.
Fibroblasts from six non-manifesting LRRK2G2019S -carriers (NM-LRRK2G2019S) and seven patients with LRRK2G2019S -associated PD (PD-LRRK2G2019S) were compared to eight healthy controls (C). An exhaustive assessment of mitochondrial performance and autophagy was performed after 24-h exposure to standard (glucose) or mitochondrial-challenging environment (galactose), where mitochondrial and autophagy impairment may be heightened.
A similar mitochondrial phenotype of NM-LRRK2G2019S and controls, except for an early mitochondrial depolarization (54.14% increased, p = 0.04), was shown in glucose. In response to galactose, mitochondrial dynamics of NM-LRRK2G2019S improved (- 17.54% circularity, p = 0.002 and + 42.53% form factor, p = 0.051), probably to maintain ATP levels over controls. A compromised bioenergetic function was suggested in PD-LRRK2G2019S when compared to controls in glucose media. An inefficient response to galactose and worsened mitochondrial dynamics (- 37.7% mitochondrial elongation, p = 0.053) was shown, leading to increased oxidative stress. Autophagy initiation (SQTSM/P62) was upregulated in NM-LRRK2G2019S when compared to controls (glucose + 118.4%, p = 0.014; galactose + 114.44%, p = 0.009,) and autophagosome formation increased in glucose media. Despite of elevated SQSTM1/P62 levels of PD-NMG2019S when compared to controls (glucose + 226.14%, p = 0.04; galactose + 78.5%, p = 0.02), autophagosome formation was deficient in PD-LRRK2G2019S when compared to NM-LRRK2G2019S (- 71.26%, p = 0.022).
Enhanced mitochondrial performance of NM-LRRK2G2019S in mitochondrial-challenging conditions and upregulation of autophagy suggests that an exhaustion of mitochondrial bioenergetic and autophagic reserve, may contribute to the development of PD in LRRK2G2019S mutation carriers.
• Keywords: Autophagy, Fibroblasts, G2019S, Galactose, Glucose, LRRK2, Mitochondrial dynamics, Mitochondrial dysfunction, Non-manifesting carriers, Parkinson’s disease • Bioblast editor: Kandolf G • O2k-Network Lab: ES Barcelona Moren C
Labels: MiParea: Respiration, mtDNA;mt-genetics, nDNA;cell genetics Pathology: Parkinson's
Organism: Human Tissue;cell: Fibroblast Preparation: Permeabilized cells Enzyme: Complex I, Complex IV;cytochrome c oxidase
Pathway: N HRR: Oxygraph-2k