It has been hypothesized that soluble forms of amyloid beta (Aß) and tau proteins in Alzheimer’s Disease (AD) interfere with neuronal activity causing memory deficits. Brain-derived neurotrophic factor (BDNF) is a protein regulating neuronal activity and is synthesized as a precursor pro-BDNF. BDNF regulates activity-dependent forms of synaptic plasticity such as long-term potentiation. Pro-BDNF downregulates synaptic activity and enhances long-term depression. Maturation of BDNF is regulated by tissue-type plasminogen activator (tPA) and by plasminogen activator inhibitor-1 (PAI-1). Thus, tPA/PAI-1 axis arbitrates the extracellular pro-BDNF/BDNF ratio. Plasma levels of PAI-1 are increased in AD patients. However, whether the process of BDNF maturation is altered in AD is not known. To verify this hypothesis, we will measure pro-BDNF/BDNF and tPA/PAI-1 ratios in serum and cerebrospinal fluid from AD patients and explore whether these changes correlate to those of neuropsychological and neuroimaging data. The outcome will be that of adding new biomarkers related to neuronal activity.

Předpokládá se, že rozpustné formy Amyloidu beta (Aß) a tau proteinu narušují neuronální aktivitu u Alzheimerovy nemoci (AN) a způsobují poruchy paměti. Brain-derived neurotrophic factor (BDNF) je protein regulující neuronální aktivitu a je syntetizován z prekurzoru pro-BDNF. BDNF posiluje synaptickou aktivitu mezi neurony a tím zvyšuje dlouhodobou potenciaci. Pro-BDNF naopak synaptickou aktivitu snižuje a zvyšuje tak dlouhodobou depresi mezi neurony. Maturace BDNF je regulována tkáňovým aktivátorem plazminogenu (tPA) a inhibitorem aktivátoru plazminogenu (tPA). Z toho vyplývá, že osa tPA/PAI-1 rozhoduje o extracelulárním poměru pro-BDNF/BDNF. U pacientů a AN byly pozorovány zvýšené hladiny PAI-1 v plasmě. Nicméně není známo, zda u pacientů s AN dochází k narušení procesu zrání BDNF. Tuto hypotézy budeme testovat pomocí měření poměru hladin pro-BDNF/BDNF a tPA/PAI-1 v krevním séru a mozkomíšním moku u pacientů s AN a budeme zjišťovat, zda tyto hladiny korelují s výsledky neuropsychologických testů a neurozobrazovacích metod. Výstupem projektu bude zavedení nových biomarkerů neuronové aktivity.

• Klíčová slova
• alzheimerova choroba, Alzheimer's disease, mírná kognitivní porucha, mild cognitive impairment, BDNF, Pro-BDNF, BDNF, pro-BDNF, PAI-1, tPA, PAI-1, tPA,

• NLK Publikační typ
• závěrečné zprávy o řešení grantu AZV MZ ČR

Plasminogen activator inhibitor-1 (PAI-1) impedes brain plasmin synthesis. Reduced plasmin activity facilitates cumulation of amyloid beta (Aβ) in Alzheimer's disease (AD). Since plasmin also regulates the synaptic activity, it is possible that altered PAI-1 is present in other neurodegenerative disorders. We investigated whether PAI-1 and its counter-regulatory tissue plasminogen activator (tPA) are altered in serum of patients with dementia due to frontotemporal lobar degeneration (FTLD). Thirty five FTLD patients (21 in mild cognitive impairment stage (MCI) and 14 in dementia stage) and 10 cognitively healthy controls were recruited. Serum tPA and PAI-1 protein levels were measured by anova. Correlation between biochemical and demographic data were explored by measuring Pearson correlation coefficient. Serum PAI-1 levels were elevated in the FTLD dementia group as compared to FTLD MCI and controls. tPA serum levels and PAI-1/tPA ratio did not significantly differ among groups. There was a negative correlation between PAI-1 serum levels and disease severity measured by MMSE score. No correlations of tPA serum levels and PAI-1/tPA ratio with MMSE were found. Increased PAI-1 serum levels may serve as a marker of dementia in FTLD, suggesting that, besides Aβ pathway, the plasmin system may affect cognition through synaptic activity.

• MeSH
• biologické markery krev   MeSH
• frontotemporální lobární degenerace * krev   MeSH
• inhibitor aktivátoru plazminogenu 1 * krev   MeSH
• kognitivní dysfunkce krev   MeSH
• lidé středního věku MeSH
• lidé MeSH
• senioři MeSH
• studie případů a kontrol MeSH
• tkáňový aktivátor plazminogenu krev   metabolismus   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Alzheimer's disease (AD) is a central nervous system (CNS) disease characterized by loss of memory, cognitive functions, and neurodegeneration. Plasmin is an enzyme degrading many plasma proteins. In the CNS, plasmin may reduce the accumulation of beta amyloid (Aβ) and have other actions relevant to AD pathophysiology. Brain plasmin synthesis is regulated by two enzymes: one activating, the tissue plasminogen activator (tPA), and the other inhibiting, the plasminogen activator inhibitor-1 (PAI-1). We investigated the levels of tPA and PAI-1 in serum from 40 AD and 40 amnestic mild cognitively impaired (aMCI) patients compared to 10 cognitively healthy controls. Moreover, we also examined the PAI-1/tPA ratio in these patient groups. Venous blood was collected and the PAI-1 and tPA serum concentrations were quantified using sandwich ELISAs. The results showed that PAI-1 levels increased in AD and aMCI patients. This increase negatively correlated with cognitive performance measured using the Mini-Mental Status Exam (MMSE). Similarly, the ratio between tPA and PAI-1 gradually increases in aMCI and AD patients. This study demonstrates that AD and aMCI patients have altered PAI-1 serum levels and PAI-1/tPA ratio. Since these enzymes are CNS regulators of plasmin, PAI-1 serum levels could be a marker reflecting cognitive decline in AD.

• Publikační typ
• časopisecké články MeSH

Epilepsy as a chronic neurological disorder is characterized by recurrent, unprovoked epileptic seizures. In about half of the people who suffer from epilepsy, the root cause of the disorder is unknown. In the other cases, different factors can cause the onset of epilepsy. In recent years, the role of gut microbiota has been recognized in many neurological disorders, including epilepsy. These data are based on studies of the gut microbiota-brain axis, a relationship starting by a dysbiosis followed by an alteration of brain functions. Interestingly, epileptic patients may show signs of dysbiosis, therefore the normalization of the gut microbiota may lead to improvement of epilepsy and to greater efficacy of anticonvulsant drugs. In this descriptive review, we analyze the evidences for the role of gut microbiota in epilepsy and hypothesize a mechanism of action of these microorganisms in the pathogenesis and treatment of the disease. Human studies revealed an increased prevalence of Firmicutes in patients with refractory epilepsy. Exposure to various compounds can change microbiota composition, decreasing or exacerbating epileptic seizures. These include antibiotics, epileptic drugs, probiotics and ketogenic diet. Finally, we hypothesize that physical activity may play a role in epilepsy through the modulation of the gut microbiota.

• MeSH
• dysbióza * MeSH
• epilepsie * metabolismus   mikrobiologie   patofyziologie   MeSH
• Firmicutes * klasifikace   metabolismus   MeSH
• lidé MeSH
• mozek patofyziologie   MeSH
• střevní mikroflóra * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH