Earlier study from our group indicated that the peroxisome proliferator-activated receptor-alpha agonist fenofibrate prevents 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced dopaminergic cell loss in C57Bl/6 mice. Our objective was to determine whether or not fibratescan improve motor activity in two experimental models of Parkinson's disease: the MPTP C57Bl/6 mouse and the 6-hydroxydopamine (6-OHDA) Wistar rat. Six groups of mice were set up: sham, sham-fenofibrate, sham-bezafibrate, MPTP, MPTP-fenofibrate and MPTP-bezafibrate. Mice were fed a diet containing 0.2% fenofibrate, 0.2% bezafibrate or no hypolipidaemic agent for 2 weeks. Four groups of rats were set up: sham, sham-fenofibrate, 6-OHDA and 6-OHDA-fenofibrate. Rats were fed a diet containing 0.2% fenofibrate or no hypolipidaemic agent for 4 weeks. In mice, motor activity was quantified using actimetry. Nine parameters were recorded. The results were analyzed with a mixed linear model. In rats, behavioural sensitization was studied with repetitive injections of apomorphine. All the actimetry parameters indicated a decrease of locomotion the day after MPTP injections and eight parameters improved in MPTP mice treated with fenofibrate or bezafibrate. The apomorphine-induced rotation behaviour mildly decreased in 6-OHDA rats treated with fenofibrate, but behavioural sensitization was unchanged. The 6-OHDA and MPTP compounds have different toxicity mechanisms, which could explain why we did not observe the same effect in 6-OHDA rats as in MPTP mice. These data suggest that the protective effect of fibrates can be carried through inhibition of inflammation rather than oxidative stress.
7 July 2020 in Tremor and Other Hyperkinetic Movements
Tremor is an important phenotypic feature of dystonia. Using the new concept (Col-Cap) of classification we examined the frequency of tremor in cervical dystonia (CD) patients, their main subtypes and muscles injected. In this large study conducted at multiple movement disorder centres in Europe and India, between January and June 2019, we examined 293 patients with idiopathic CD who were all treated with botulinum toxin (BTX). The dystonic head tremor (DHT+) was present in 57.6 % of CD patients and they had a significantly longer duration of symptoms than patients without head tremor (DHT–). In DHT+ patients torticaput was the most common subtype and the majority (63.3%) had one or two subtypes only. There was no significant difference between the number of unilateral injections for any of the muscles in the DHT+ and DHT– groups, while the number of patients receiving bilateral injections in splenius capitis (78 vs 25; p = 0.00001), sternocleidomastoid (31 vs 6; p = 0.0005), trapezius (28 vs 9; p = 0.01), and obliquus capitis inferior (15 vs 2; p = 0.008) were significantly more in the DHT+ group. The mean doses of all three types of BTX/A were not significantly different between the two groups. The frequency of head tremor was 57.6% in our CD patients and torticaput was the most common dystonic subtype associated with tremor. Simple forms of CD seemed more likely associated with head tremor, than complex forms of CD. Most of the DHT+ patients received bilateral injections. The use of ‘Col-Cap’ classification was helpful in the identification of muscles likely to be involved in tremor in CD patients.
1 October 2016 in Journal of Speech, Language, and Hearing Research
Purpose To better define the clinical characteristics of idiopathic oromandibular dystonia, we studied voice, speech, and swallowing disorders and their impact on activities of daily living. Method Fourteen consecutive patients with idiopathic oromandibular dystonia and 14 matched, healthy control subjects were included in the study. Results Dysarthria was the most common disorder and its characteristics varied from one patient to another. However, we frequently observed a hyperkinetic, dysarthric profile characterized by imprecise consonants, a rough voice, changes in intensity, and hypernasality. Dysphagia appeared to be slightly less frequent and less disabling than dysarthria. Most patients had difficulty swallowing solids, and the oral phase was particularly problematic. Dysarthria and dysphagia affected activities of daily living in general and the psychological/emotional domain in particular. Conclusions The characteristics of dysarthria in oromandibular dystonia vary significantly from one patient to another due to differences in the set of affected muscles, so each patient should receive a personalized rehabilitation program. Dysarthria was the most prominent symptom, although spasmodic dysphonia was more frequent than expected. Further laboratory-based studies are needed to clarify the mechanisms and consequences of dysphagia in oromandibular dystonia.