CADASIL is a generalized angiopathy caused by mutations in NOTCH 3 gene leading to degeneration and loss of vascular smooth muscle cells (VSMC) in small arteries and arterioles. Since the receptor protein encoded by NOTCH 3 gene is expressed not only on VSMC but also on pericytes, pericytes and capillary vessels can be damaged by CADASIL. To check this hypothesis we examined microvessels in autopsy brains and skin-muscle biopsies of CADASIL patients. We found degeneration and loss of pericytes in capillary vessels. Pericytes were shrunken and their cytoplasm contained numerous vacuoles, big vesicular structures and complexes of enlarged pathological mitochondria. Degenerative changes were also observed within endothelial-pericytic connections, especially within peg-and-socket junctions. Nearby pericyte cell membranes or inside infoldings, deposits of granular osmiophilic material (GOM) were usually seen. In the affected capillaries endothelial cells revealed features of degeneration, selective death or swelling, leading to narrowing or occlusion of the capillary lumen. Our findings indicate that in CADASIL not only VSMC but also pericytes are severely damaged. Pericyte involvement in CADASIL can result in increased permeability of capillary vessels and disturbances in cerebral microcirculation, leading to white matter injury. Since in capillaries pericytes regulate vessel contractility, their degeneration can also cause defective vasomotor reactivity, the phenomenon observed very early in CADASIL, before development of histopathological changes in vessel walls.

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Background: Amyotrophic lateral sclerosis is a fatal motor neuron degenerative disease. Most cases are sporadic (SALS), and approximately 10% are familial (FALS) among which over 20% are linked to the SOD1 mutation. Both SALS and FALS have been associated with retrograde axonal transport defects. Kinesins (KIFs) are motor proteins involved mainly in anterograde transport; however, some also participate in retrograde transport. Objective: The purpose of the study was to investigate and compare the expression of kinesins involved in anterograde (KIF5A, 5C) and retrograde (KIFC3/C2) axonal transport in SALS in humans and FALS in mice with the hSOD1G93A mutation. Methods: The studies were conducted on various parts of the CNS from autopsy specimens of SALS patients, and transgenic mice at presymptomatic and symptomatic stages using real-time quantitative PCR and reverse-transcription PCR. Results: All KIF expression in the motor cortex of individual SALS subjects was higher than in the adjacent sensory cortex, in contrast to the expression in control brains. It was also significantly higher in the frontal cortex of symptomatic but not presymptomatic mice compared to wild-type controls. However, the mean KIF expression in the SALS motor and sensory cortexes was lower than in control cortexes. To a lesser extent the decrease in KIF mean expression also occurred in human but not in mouse ALS spinal cords and in both human and mouse cerebella. Conclusion: Disturbances in kinesin expression in the CNS may dysregulate both anterograde and retrograde axonal transports leading to motor neuron degeneration.

Dynactin is a complex motor protein involved in the retrograde axonal transport disturbances of which may lead to amyotrophic lateral sclerosis (ALS). Mice with hSOD1G93A mutation develop ALS-like symptoms and are used as a model for the disease studies. Similar symptoms demonstrate Cra1 mice, with Dync1h1 mutation. Dynactin heavy (DCTN1) and light (DCTN3) subunits were studied in the CNS of humans with sporadic ALS (SALS), mice with hSOD1G93A (SOD1/+), Dync1h1 (Cra1/+), and double (Cra1/SOD1) mutation at presymptomatic and symptomatic stages. In SALS subjects, in contrast to control cases, expression of DCTN1-mRNA but not DCTN3-mRNA in the motor cortex was higher than in the sensory cortex. However, the mean levels of DCTN1-mRNA and protein were lower in both SALS cortexes and in the spinal cord than in control structures. DCTN3 was unchanged in brain cortexes but decreased in the spinal cord on both mRNA and protein levels. In all SALS tissues immunohistochemical analyses revealed degeneration and loss of neuronal cells, and poor expression of dynactin subunits. In SOD1/+ mice both subunits expression was significantly lower in the frontal cortex, spinal cord and hippocampus than in wild-type controls, especially at presymptomatic stage. Fewer changes occurred in Cra1/SOD1 and Cra1/+ mice.It can be concluded that in sporadic and SOD1-related ALS the impairment of axonal retrograde transport may be due to dynactin subunits deficiency and subsequent disturbances of the whole dynein/dynactin complex structure and function. The Dync1h1 mutation itself has slight negative effect on dynactin expression and it alleviates the changes caused by SOD1G93A mutation.

Background: Studies show that dysphagia is a common problem in patients with demyelinating diseases. However, there are no published studies on dysphagia in this group of patients, which would include the individual phases or the safety and effectiveness of the swallowing process. Objective: The main objective of this study was to assess the prevalence of swallowing disorders and to characterize them based on subjective assessment by the study subjects with multiple sclerosis and Devic's syndrome. Method: The study included 72 patients (47 F, 25 M). Patients at risk of dysphagia were identified using the DYMUS, EAT-10 and SDQ questionnaires. To assess the type of oral-and pharyngeal-stage dysphagia, questions in the questionnaires were classified into groups according to symptoms typical of each stage. Results: The risk of dysphagia and the need for instrumental examination were identified in 37.5% of the study subjects. Pharyngeal-stage dysphagia (repeated swallowing, increased effort of swallowing, cough, a feeling of food sticking in the throat) was reported to occur at a significantly higher frequency. However, no differences were found between difficulty in swallowing liquids and difficulty in swallowing solid food. Conclusion:There is a need for further research, which should include a detailed dysphagia-oriented diagnosis, with a view to gaining a detailed insight into the pathophysiology of deglutition in this group of patients.

The expression of glutathione S-transferase pi (GST pi), an enzyme responsible for inactivation of a large variety of toxic compounds was studied in spinal cord, motor and sensory brain cortex obtained from patients who died in the course of amyotrophic lateral sclerosis (ALS). The studies were performed on formalin-fixed, paraffin-embedded (FFPE) and freshly frozen tissues. The method of RNA isolation from FFPE was modified. A significant decrease of GST pi-mRNA expression was found in cervical spinal cord and motor brain cortex of ALS subjects comparing to analogue control tissues (P<0.01), as well as in motor cortex of ALS subjects comparing to their sensory cortex (P<0.05). In spinal cords the decrease in GST pi-mRNA expression was accompanied by a decrease of GST pi protein level. Results indicated lowered GST pi expression on both mRNA and protein levels in the regions of nervous system affected by ALS. The non-properly inactivated by GST toxic electrophiles and organic peroxides may thus contribute to motor neurons damage.

We morphologically examined human brains several years after a territorial ischemic stroke to assess the development of progressing white matter damage and its pathomechanisms. Our investigations focused on the role of TGF-beta, one of the factors whose expression increases after tissue damage, and its receptor endoglin in the propagation of postischemic injury. Examination of the white matter adjacent to the postapoplectic cavity revealed structural changes in the capillary vessels, disturbed microcirculation, and deep endothelial cell damage with DNA fragmentation in the TUNEL reaction. Many oligodendrocytes also revealed DNA damage and an increased expression of caspase-3. In the rarefied white matter, the microvessel immune reaction to TGF-beta was diminished while the expression of endoglin was heterogeneous: absent in some capillaries but increased in others in comparison to the vessels located more peripherally from the cavity and in the control material. We conclude that endoglin and TGF-beta can be involved in the development of the microangiopathy responsible for the propagation of postischemic white matter injury in humans. We suggest that disturbances in endoglin expression can influence TGF-beta signaling and, consequently, vessel structure and function. Pronounced endoglin expression can lead to decreased vessel wall integrity while a lack of the constitutively expressed protein is probably a mirror of deep vessel damage.

A b s t r a c t (Sub)chronic local drug application is clearly superior to systemic administration, but may be associated with substantial obstacles, particularly regarding the applications to highly sensitive central nervous system (CNS) structures