The most pathological effects of Huntington’s disease (HD) are focused on the central nervous system but numerous reports had described abnormalities in peripheral tissues. Mutant huntingtin (Htt) has been implicated in disruptions of multiple cellular processes, including mitochondrial functions whose impairment contributes to the pathogenesis of HD.
The aim was to analyse mitochondrial bioenergetics in somatic and germ cells from HD patients and minipig boars transgenic (TgHD) for the N-terminal part of human mutated Htt.
Material Cultivated fibroblasts, sperm and buccal epithelial cells (BEC) were collected after informed consent from 8 HD symptomatic patients (22–74 years) with 43–58 CAG triplet repeats and from TgHD and WT minipigs of F0 - F2 generations (12–60 months).
Methods Respiratory chain complexes (RCC) activity and amount were analysed by spectrophotometric, imunoelectrophoretic and by dipstick immunocapture method (Mitosciences). Respiration was measured by polarography. Mitochondrial energy generating system (MEGS) capacity was characterised by oxidation rate of labelled substrates. Mitochondrial ultrastructure, network and reactive oxygen species (ROS) were visualised using fluorescent and electron microscopy.
Results Swollen mitochondria, fragmented network, increased ROS level, decreased respiration and selectively decreased level of RCC I and IV were detected in HD patient´s and TgHD minipig fibroblasts in comparison with controls. Impaired mitochondrial respiration, reduced MEGS and decreased RCC II activity was found in sperm of TgHD boars and in one HD patient. Amount of RCC I and IV in BEC was decreased in all HD patients and in two from three asymptomatic TgHD minipigs compared to controls.
Conclusion Tested cells could serve for noninvasive monitoring of mitochondrial impairment incurred in connexion with HD even in presymptomatic stages of disease.
Supported TA01011466, ExAM-CZ.1.05./2.1.00/03.0124, PRVOUK-P24/LF1/3, PRVOUK-P26/LF1/4.
- respiratory chain