membrane function
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Phosphofurin acidic cluster sorting protein 2 (PACS2) plays a vital role in maintaining cellular homeostasis by regulating protein trafficking between cellular membranes. This function impacts crucial processes like apoptosis, mitochondria-endoplasmic reticulum interaction, and subsequently Ca2+ flux, lipid biosynthesis, and autophagy. Missense mutations, particularly E209K and E211K, are linked to developmental and epileptic encephalopathy-66 (DEE66), known as PACS2 syndrome. Individuals with this syndrome exhibit neurodevelopmental delay, seizures, facial dysmorphism, hypotonia, and delayed motor skills.Understanding the impact of these missense mutations on molecular processes is crucial. Studies suggest that E209K mutation decreases phosphorylation, increases the survival time of protein, and modifies protein-protein interaction, consequently leading to disruption of calcium flux and lower resistance to apoptosis induction. Unfortunately, to date, only a limited number of research groups have investigated the effects of mutations in the PACS2 gene. Current research on PACS2 syndrome is hampered by the lack of suitable models. While in vitro models using transfected cell lines offer insights, they cannot fully capture the disease's complexity.To address this, utilizing cells from individuals with PACS2 syndrome, specifically induced pluripotent stem cells (iPSCs), holds promise for understanding phenotypic diversity and developing personalized therapies. However, iPSC models may not fully capture tissue-specific effects of the E209K/E211K mutation. In vivo studies using animal models, particularly mice, could overcome these limitations.This review summarizes current knowledge about PACS2 structure and functions, explores the cellular consequences of E209K and E211K mutations, and highlights the potential of iPSC and mouse models in advancing our understanding of PACS2 syndrome.
The glycoprotein clusterin (CLU) is involved in cell proliferation and DNA damage repair and is highly expressed in tumor cells. Here, we aimed to investigate the effects of CLU dysregulation on two human astrocytic cell lines: CCF-STTG1 astrocytoma cells and SV-40 immortalized normal human astrocytes. We observed that suppression of CLU expression by RNA interference inhibited cell proliferation, triggered the DNA damage response, and resulted in cellular senescence in both cell types tested. To further investigate the underlying mechanism behind these changes, we measured reactive oxygen species, assessed mitochondrial function, and determined selected markers of the senescence-associated secretory phenotype. Our results suggest that CLU deficiency triggers oxidative stress-mediated cellular senescence associated with pronounced alterations in mitochondrial membrane potential, mitochondrial mass, and expression levels of OXPHOS complex I, II, III and IV, indicating mitochondrial dysfunction. This report shows the important role of CLU in cell cycle maintenance in astrocytes. Based on these data, targeting CLU may serve as a potential therapeutic approach valuable for treating gliomas.
- MeSH
- astrocyty * metabolismus patologie MeSH
- klusterin * metabolismus genetika MeSH
- lidé MeSH
- membránový potenciál mitochondrií * fyziologie MeSH
- mitochondrie * metabolismus MeSH
- nádorové buněčné linie MeSH
- oxidační stres fyziologie MeSH
- oxidativní fosforylace MeSH
- poškození DNA MeSH
- proliferace buněk * MeSH
- reaktivní formy kyslíku metabolismus MeSH
- stárnutí buněk * fyziologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
The alveolar-capillary interface is the key functional element of gas exchange in the human lung, and disruptions to this interface can lead to significant medical complications. However, it is currently challenging to adequately model this interface in vitro, as it requires not only the co-culture of human alveolar epithelial and endothelial cells but mainly the preparation of a biocompatible scaffold that mimics the basement membrane. This scaffold should support cell seeding from both sides, and maintain optimal cell adhesion, growth, and differentiation conditions. Our study investigates the use of polycaprolactone (PCL) nanofibers as a versatile substrate for such cell cultures, aiming to model the alveolar-capillary interface more accurately. We optimized nanofiber production parameters, utilized polyamide mesh UHELON as a mechanical support for scaffold handling, and created 3D-printed inserts for specialized co-cultures. Our findings confirm that PCL nanofibrous scaffolds are manageable and support the co-culture of diverse cell types, effectively enabling cell attachment, proliferation, and differentiation. Our research establishes a proof-of-concept model for the alveolar-capillary interface, offering significant potential for enhancing cell-based testing and advancing tissue-engineering applications that require specific nanofibrous matrices.
BACKGROUND: A number of recent studies have shown that the intestinal microbiome, part of the brain-gut axis, is implicated in the pathophysiology of multiple sclerosis. An essential part of this axis, is the intestinal barrier and gastrointestinal disorders with intestinal barrier dysregulation appear to be linked to CNS demyelination, and hence involved in the etiopathogenesis of multiple sclerosis (MS). OBJECTIVE: The aim of this study was to evaluate the integrity of the intestinal barrier in patients with clinically definite multiple sclerosis (CDMS) and clinically isolated syndrome (CIS) using two serum biomarkers, claudin-3 (CLDN3), a component of tight epithelial junctions, and intestinal fatty acid binding protein (I-FABP), a cytosolic protein in enterocytes. METHODS: Serum levels of CLDN3 in 37 MS patients and 22 controls, and serum levels of I-FABP in 46 MS patients and 51 controls were measured using commercial ELISA kits. Complete laboratory tests excluded the presence of gluten-related disorders in all subjects. Thirty MS patients received either disease-modifying drugs (DMD), immunosuppression (IS) or corticosteroid treatment. RESULTS: CLDN3 levels were only significantly higher in the MS patients treated with DMD or IS compared to the control group (P=0.006). There were no differences in I-FABP serum levels between the groups. Serum CLDN3 levels did not correlate with serum I-FABP levels in CDMS, in CIS patients or controls. CONCLUSIONS: In multiple sclerosis patients, the intestinal epithelium may be impaired with increased permeability, but without significant enterocyte damage characterized by intracellular protein leakage. Based on our data, CLDN3 serum levels appear to assess intestinal dysfunction in MS patients but mainly in treated ones.
- MeSH
- biologické markery * krev MeSH
- claudin-3 * metabolismus MeSH
- dospělí MeSH
- funkce střevní bariéry MeSH
- lidé středního věku MeSH
- lidé MeSH
- permeabilita * MeSH
- proteiny vázající mastné kyseliny * krev MeSH
- roztroušená skleróza * patofyziologie metabolismus krev MeSH
- střevní sliznice metabolismus MeSH
- studie případů a kontrol MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Cílem práce je na ojedinělém případu pacienta po nadstandardní operaci šedého zákalu s preventivní primární zadní cirkulární kasulorexi (PCCC, z angl. posterior continuous curvilinear capsulorhexis) prezentovat možný vznik proliferativní sekundární katarakty. Vzhledem k negativnímu vlivu na zrakové funkce bylo rozhodnuto o ošetření Nd:YAG laserem, které bylo úspěšné s použitím minimální energie ale s porušením přední hyaloidní membrány. Kazuistika 65letý muž podstoupil na našem pracovišti v roce 2020 nekomplikovanou operaci šedého zákalu obou očí, oboustranně s primární PCCC s implantací tenzního kroužku a umělé nitrooční čočky do pouzdra. V únoru 2023 byl na doporučení spádového očního lékaře vyšetřen na naší ambulanci pro snížení zrakové ostrosti vpravo. Dominantní bylo rozmazané vidění. Diagnóza proliferativní formy sekundární katarakty byla potvrzena a zdokumentována pomocí fotografie předního segmentu v retroiluminaci a předněsegmentového OCT (Optovue, Avanti RTVue XR). Pacient byl indikován k Nd:YAG laserové disrupci proliferací v prostoru PCCC na pravém oku. Návrat zrakové ostrosti k původnímu stavu byl potvrzením správné diagnózy. V literárním přehledu a v diskuzi je shrnuta aktuální problematika sekundární katarakty a použití primární PCCC. Závěr: Sekundární katarakta je hlavní dlouhodobou komplikací moderní chirurgie katarakty. Jednou z možných řešení je preventivní provedení jednoduché PCCC, která může být provázená ojedinělým selháním.
The aim of the study is to present the possible development of proliferative secondary cataracts in the unique case of a patient having undergone premium cataract surgery with preventive primary posterior continuous curvilinear capsulorhexis (PCCC). Due to the negative effect on visual functions, it was decided to treat the patient with an Nd:YAG laser, which was successful with minimal energy but resulted in damage to the anterior hyaloid membrane. Case report In 2020, a 65-year-old man underwent uncomplicated cataract surgery in both eyes at our clinic bilaterally with primary PCCC with implantation of a tension ring and an artificial intraocular lens into the capsule. In February 2023, on the recommendation of the area ophthalmologist, he was examined at our outpatient clinic due to a decrease of visual acuity in the right eye. Blurred vision predominated. A diagnosis of proliferative form of secondary cataract was confirmed and documented using a photo of the anterior segment in retroillumination and anterior segment OCT (Optovue, Avanti RTVue XR). The patient was indicated for Nd:YAG laser disruption by proliferation in the PCCC space in the right eye. The return of visual acuity to its original state confirmed the correct diagnosis. The literature review and discussion summarize the current issue of secondary cataracts and the use of primary PCCC. Conclusion: Secondary cataract is the main long-term complication of modern cataract surgery. One of the possible solutions is the preventive implementation of a simple PCCC, which may be accompanied by isolated failure.
- MeSH
- capsulorhexis * metody škodlivé účinky MeSH
- extrakce katarakty metody škodlivé účinky MeSH
- implantace nitrooční čočky MeSH
- katarakta etiologie MeSH
- lasery pevnolátkové terapeutické užití MeSH
- lidé MeSH
- senioři MeSH
- zkalení zadního pouzdra čočky diagnóza etiologie MeSH
- zraková ostrost MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- Publikační typ
- kazuistiky MeSH
Účel studie: Radiosynoviortéza (RSO), dříve též nazývána slovem radiosynovektomie (RS), je metoda zaměřená na léčbu bolesti a otoku kloubů způsobených synovitidou u artritid a dekompenzovaných artróz prostřednictvím lokální aplikace beta zářičů. Zářením vyvolaná povrchová nekróza části buněk v synoviální membráně ve svém výsledku může zmírnit bolest, snížit otoky a zlepšit funkci kloubů. Materiál a metoda: V období 2013–2024 bylo RSO léčeno celkem 436 pacientů, z toho 291 pro otok kolenního kloubu vzniklý v důsledku dekompenzované artrózy a 172 kvůli artritidě. Kolenní kloub byl RSO ošetřen 268krát a malé a střední klouby 50krát. Používalo se yttrium u kolenních kloubů, rhenium u středních nebo erbium u malých kloubů. Samotný zákrok spočíval v punkci kloubu a odsátí případného kloubního výpotku, následné aplikaci radiofarmaka a imobilizaci kloubu po dobu 2–3 dnů. Výsledky: K hodnocení klinického efektu RSO jsme vybrali aplikace v letech 2022 a 2023. V roce 2022 bylo provedeno 45 ošetření a v roce 2023 dalších 26. Po jednom roce bylo 61 % pacientů s léčbou kolenních kloubů zcela spokojeno, přičemž uváděli zmenšení otoku a zlepšení rozsahu pohybu. U pacientů léčených s malými a středně velkými klouby se celkové zlepšení objevilo u 57 % z nich. Někteří zaznamenali recidivující výpotek menšího objemu nebo jen částečné zlepšení. Závěr: Radiosynoviortéza je účinná léčba otoků a bolesti kloubů způsobených synovitidou s pozitivními výsledky jak u kolenních, tak i menších kloubů, což je doloženo jak objektivními, tak subjektivními zlepšeními.
Purpose of the study: Radiosynoviorthesis (RSO), previously also called radiosynovectomy (RS), is a method focused on the treatment of joint pain and swelling caused by synovitis in arthritis and decompensated osteoarthrosis using beta emitters. Radiation-induced surface necrosis of part of the cells in the synovial membrane can, as a result, relieve pain, reduce swelling, and improve joint function. Material and method: Between 2013-2024, 436 patients were treated with RSO, primarily for knee joint swelling due to decompensated osteoarthrosis (291 patients) and arthritis (172 patients). RSO was performed on the knee (268 cases) and on small/medium joints (50 cases), using yttrium for knee joints, rhenium for medium joins or erbium for small joints. The procedure involved puncture of the joint and suction of any joint effusion, injecting the radioactive isotope, and subsequently immobilizing the joint for 2–3 days. Results: We selected treatments in 2022 and 2023 to evaluate the clinical effect of RSO. In 2022, 45 treatments were performed, and in 2023 another 26. One year post-treatment, 61 % of patients with knee joint involvement were fully satisfied, reporting reduced swelling and improved range of motion. Among patients treated for small and medium-sized joints, 57 % experienced overall improvement. Some patients observed recurring effusions of smaller volume or only partial improvement. Conclusion: Radiosynoviorthesis is an effective treatment for joint swelling and pain caused by synovitis, with positive outcomes seen in knee as well as smaller joints. Both objective and subjective assessments confirmed significant benefits.
- Klíčová slova
- radiosynoviortéza,
- MeSH
- artritida diagnostické zobrazování radioterapie MeSH
- erbium aplikace a dávkování terapeutické užití MeSH
- injekce intraartikulární MeSH
- klinické zkoušky jako téma MeSH
- osteoartróza diagnostické zobrazování radioterapie MeSH
- radiofarmaka * aplikace a dávkování terapeutické užití MeSH
- radioizotopy ytria aplikace a dávkování terapeutické užití MeSH
- rhenium aplikace a dávkování terapeutické užití MeSH
- synovitida * diagnostické zobrazování radioterapie MeSH
Background: Activation of cannabinoid receptor 1 (CB1R) in the nervous system modulates the processing of acute and chronic pain. CB1R activity is regulated by desensitization and internalization. SH3-containing GRB2-like protein 3-interacting protein 1 (SGIP1) inhibits the internalization of CB1R. This causes increased and prolonged association of the desensitized receptor with G protein-coupled receptor kinase 3 (GRK3) and beta-arrestin on the cell membrane and results in decreased activation of extracellular signal-regulated kinase 1/2 (ERK1/2) pathway. Genetic deletion of SGIP1 in mice leads to altered CB1R-related functions, such as decreased anxiety-like behaviors, modified cannabinoid tetrad behaviors, reduced acute nociception, and increased sensitivity to analgesics. In this work, we asked if deletion of SGIP1 affects chronic nociception and analgesic effect of Δ9-tetrahydrocannabinol (THC) and WIN 55,212-2 (WIN) in mice. Methods: We measured tactile responses of hind paws to increasing pressure in wild-type and SGIP1 knock-out mice. Inflammation in the paw was induced by local injection of carrageenan. To determine the mechanical sensitivity, the paw withdrawal threshold (PWT) was measured using an electronic von Frey instrument with the progression of the applied force. Results: The responses to mechanical stimuli varied depending on the sex, genotype, and treatment. SGIP1 knock-out male mice exhibited lower PWT than wild-type males. On the contrary, the female mice exhibited comparable PWT. Following THC or WIN treatment in male mice, SGIP1 knock-out males exhibited PWT lower than wild-type males. THC treatment in SGIP1 knock-out females resulted in PWT higher than after THC treatment of wild-type females. However, SGIP1 knock-out and wild-type female mice exhibited similar PWT after WIN treatment. Conclusions: We provide evidence that SGIP1, possibly by interacting with CB1R, is involved in processing the responses to chronic pain. The absence of SGIP1 results in enhanced sensitivity to mechanical stimuli in males, but not females. The antinociceptive effect of THC is superior to that of WIN in SGIP1 knock-out mice in the carrageenan-induced model of chronic pain.
- MeSH
- benzoxaziny * farmakologie MeSH
- hyperalgezie * genetika MeSH
- morfoliny farmakologie MeSH
- myši inbrední C57BL MeSH
- myši knockoutované * MeSH
- myši MeSH
- naftaleny MeSH
- nocicepce účinky léků MeSH
- receptor kanabinoidní CB1 * genetika metabolismus MeSH
- tetrahydrokanabinol * farmakologie MeSH
- zánět * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Posterior fossa syndrome (PFS) is a serious postoperative complication that primarily affects children following resection of posterior fossa tumors. Although its complex pathophysiology, involving disruption of cerebellar structures and the dentato-thalamo-cortical pathway, is increasingly being elucidated, effective treatments remain limited. This perspective explores acetyl-DL-leucine (ADLL) and its active L-enantiomer, N-acetyl-L-leucine (NALL), as promising therapeutic candidates for PFS. Emerging mechanistic, preclinical, and clinical evidence suggests that both compounds might alleviate PFS symptoms through neuroprotective and neurorestorative mechanisms, including neuronal membrane stabilization, metabolic enhancement, antioxidant and anti-inflammatory effects, and dopaminergic modulation. NALL, which has greater neurotherapeutic potential than ADLL, might particularly support recovery through its multimodal effects on neuronal function, thereby enhancing perioperative resilience. Further translational research into these acetylated leucine analogues is warranted.
- MeSH
- infratentoriální nádory * chirurgie MeSH
- leucin * analogy a deriváty terapeutické užití farmakologie MeSH
- lidé MeSH
- neuroprotektivní látky * farmakologie terapeutické užití MeSH
- pooperační komplikace * farmakoterapie MeSH
- syndrom MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Nedd4-2 E3 ligase regulates Na+ homeostasis by ubiquitinating various channels and membrane transporters, including the epithelial sodium channel ENaC. In turn, Nedd4-2 dysregulation leads to various conditions, including electrolytic imbalance, respiratory distress, hypertension, and kidney diseases. However, Nedd4-2 regulation remains mostly unclear. The present study aims at elucidating Nedd4-2 regulation by structurally characterizing Nedd4-2 and its complexes using several biophysical techniques. Our cryo-EM reconstruction shows that the C2 domain blocks the E2-binding surface of the HECT domain. This blockage, ubiquitin-binding exosite masking by the WW1 domain, catalytic C922 blockage and HECT domain stabilization provide the structural basis for Nedd4-2 autoinhibition. Furthermore, Ca2+-dependent C2 membrane binding disrupts C2/HECT interactions, but not Ca2+ alone, whereas 14-3-3 protein binds to a flexible region of Nedd4-2 containing the WW2 and WW3 domains, thereby inhibiting its catalytic activity and membrane binding. Overall, our data provide key mechanistic insights into Nedd4-2 regulation toward fostering the development of strategies targeting Nedd4-2 function.
- MeSH
- elektronová kryomikroskopie MeSH
- HEK293 buňky MeSH
- lidé MeSH
- molekulární modely MeSH
- proteinové domény MeSH
- proteiny 14-3-3 * metabolismus chemie MeSH
- ubikvitinace MeSH
- ubikvitinligasy Nedd4 * metabolismus chemie genetika ultrastruktura MeSH
- vápník * metabolismus MeSH
- vazba proteinů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Mitochondria are central to cellular energy metabolism, contributing to synaptic transmission and plasticity. The mitochondrial membranes present the cannabinoid type-1 receptor (mito-CB1R), which has been functionally linked to neuronal energy supply and cognitive processing. Prenatal exposure to Δ9-tetrahydrocannabinol (pTHC) has been associated with cognitive impairments associated with molecular cellular and functional abnormalities in several brain regions, including the hippocampus. This study aims at assessing whether, besides the memory impairment, pTHC exposure may result in mitochondrial molecular and functional alterations in the hippocampus of the offspring. Moreover, the assessment of CB1R expression is also carried out as a proxy of CB1 signalling in pTHC-exposed offspring. THC (2 mg/Kg), or vehicle, was administered to the dams from gestational day (GD) 5 to GD20, and the offspring were tested for declarative memory using the Novel Object Recognition test in the L-maze. We also assessed: mitochondrial respiration by high-resolution respirometry; mitochondrial respiratory complex-I subunit NDUFS1 protein levels, and mito-CB1R expression by ELISA. Our results revealed: significant memory impairment in pTHC-exposed offspring; attenuated mitochondrial respiration in the hippocampus alongside a marked reduction in complex-I-subunit NDUFS1; a significant increase in mito-CB1R expression. This is the first evidence of pTHC exposure-induced impairment in memory processing in the offspring that suggests a functional link between an attenuation in mitochondrial bioenergetics and abnormal CB1R signalling in the hippocampus.
- MeSH
- bludiště - učení účinky léků MeSH
- buněčné dýchání účinky léků MeSH
- hipokampus * metabolismus účinky léků MeSH
- krysa rodu rattus MeSH
- mitochondrie * metabolismus účinky léků MeSH
- paměť účinky léků MeSH
- poruchy paměti * metabolismus chemicky indukované MeSH
- potkani Wistar MeSH
- receptor kanabinoidní CB1 * metabolismus MeSH
- těhotenství MeSH
- tetrahydrokanabinol * toxicita MeSH
- zpožděný efekt prenatální expozice * metabolismus chemicky indukované MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH