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
- Astrocytes * metabolism pathology MeSH
- Clusterin * metabolism genetics MeSH
- Humans MeSH
- Membrane Potential, Mitochondrial * physiology MeSH
- Mitochondria * metabolism MeSH
- Cell Line, Tumor MeSH
- Oxidative Stress physiology MeSH
- Oxidative Phosphorylation MeSH
- DNA Damage MeSH
- Cell Proliferation * MeSH
- Reactive Oxygen Species metabolism MeSH
- Cellular Senescence * physiology MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Heavy metals are naturally occurring components of the Earth's crust and persistent environmental pollutants. Human exposure to heavy metals occurs via various pathways, including inhalation of air/dust particles, ingesting contaminated water or soil, or through the food chain. Their bioaccumulation may lead to diverse toxic effects affecting different body tissues and organ systems. The toxicity of heavy metals depends on the properties of the given metal, dose, route, duration of exposure (acute or chronic), and extent of bioaccumulation. The detrimental impacts of heavy metals on human health are largely linked to their capacity to interfere with antioxidant defense mechanisms, primarily through their interaction with intracellular glutathione (GSH) or sulfhydryl groups (R-SH) of antioxidant enzymes such as superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), glutathione reductase (GR), and other enzyme systems. Although arsenic (As) is believed to bind directly to critical thiols, alternative hydrogen peroxide production processes have also been postulated. Heavy metals are known to interfere with signaling pathways and affect a variety of cellular processes, including cell growth, proliferation, survival, metabolism, and apoptosis. For example, cadmium can affect the BLC-2 family of proteins involved in mitochondrial death via the overexpression of antiapoptotic Bcl-2 and the suppression of proapoptotic (BAX, BAK) mechanisms, thus increasing the resistance of various cells to undergo malignant transformation. Nuclear factor erythroid 2-related factor 2 (Nrf2) is an important regulator of antioxidant enzymes, the level of oxidative stress, and cellular resistance to oxidants and has been shown to act as a double-edged sword in response to arsenic-induced oxidative stress. Another mechanism of significant health threats and heavy metal (e.g., Pb) toxicity involves the substitution of essential metals (e.g., calcium (Ca), copper (Cu), and iron (Fe)) with structurally similar heavy metals (e.g., cadmium (Cd) and lead (Pb)) in the metal-binding sites of proteins. Displaced essential redox metals (copper, iron, manganese) from their natural metal-binding sites can catalyze the decomposition of hydrogen peroxide via the Fenton reaction and generate damaging ROS such as hydroxyl radicals, causing damage to lipids, proteins, and DNA. Conversely, some heavy metals, such as cadmium, can suppress the synthesis of nitric oxide radical (NO·), manifested by altered vasorelaxation and, consequently, blood pressure regulation. Pb-induced oxidative stress has been shown to be indirectly responsible for the depletion of nitric oxide due to its interaction with superoxide radical (O2·-), resulting in the formation of a potent biological oxidant, peroxynitrite (ONOO-). This review comprehensively discusses the mechanisms of heavy metal toxicity and their health effects. Aluminum (Al), cadmium (Cd), arsenic (As), mercury (Hg), lead (Pb), and chromium (Cr) and their roles in the development of gastrointestinal, pulmonary, kidney, reproductive, neurodegenerative (Alzheimer's and Parkinson's diseases), cardiovascular, and cancer (e.g. renal, lung, skin, stomach) diseases are discussed. A short account is devoted to the detoxification of heavy metals by chelation via the use of ethylenediaminetetraacetic acid (EDTA), dimercaprol (BAL), 2,3-dimercaptosuccinic acid (DMSA), 2,3-dimercapto-1-propane sulfonic acid (DMPS), and penicillamine chelators.
- MeSH
- Antioxidants metabolism MeSH
- Bioaccumulation MeSH
- Environmental Pollutants toxicity MeSH
- Humans MeSH
- Oxidative Stress * drug effects MeSH
- Metals, Heavy * toxicity MeSH
- Environmental Exposure adverse effects MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
Cyanobacteria are prokaryotic organisms characterised by their complex structures and a wide range of pigments. With their ability to fix CO2, cyanobacteria are interesting for white biotechnology as cell factories to produce various high-value metabolites such as polyhydroxyalkanoates, pigments, or proteins. White biotechnology is the industrial production and processing of chemicals, materials, and energy using microorganisms. It is known that exposing cyanobacteria to low levels of stressors can induce the production of secondary metabolites. Understanding of this phenomenon, known as hormesis, can involve the strategic application of controlled stressors to enhance the production of specific metabolites. Consequently, precise measurement of cyanobacterial viability becomes crucial for process control. However, there is no established reliable and quick viability assay protocol for cyanobacteria since the task is challenging due to strong interferences of autofluorescence signals of intercellular pigments and fluorescent viability probes when flow cytometry is used. We performed the screening of selected fluorescent viability probes used frequently in bacteria viability assays. The results of our investigation demonstrated the efficacy and reliability of three widely utilised types of viability probes for the assessment of the viability of Synechocystis strains. The developed technique can be possibly utilised for the evaluation of the importance of polyhydroxyalkanoates for cyanobacterial cultures with respect to selected stressor-repeated freezing and thawing. The results indicated that the presence of polyhydroxyalkanoate granules in cyanobacterial cells could hypothetically contribute to the survival of repeated freezing and thawing.
Apple replant disease (ARD) is a significant factor restricting the healthy development of the apple industry. Biological control is an important and sustainable method for mitigating ARD. In this study, a strain of Paenibacillus polymyxa GRY-11 was isolated and screened from the rhizosphere soil of healthy apple trees in old apple orchards in Shandong Province, China, and the effects of strain GRY-11 on soil microbial community and ARD were studied. The result showed that P. polymyxa GRY-11 could effectively inhibit the growth of the main pathogenic fungi that caused ARD, and the inhibition rates of the strain against Fusarium moniliforme, Fusarium proliferatum, Fusarium solani, and Fusarium oxysporum were 80.00%, 71.60%, 75.00%, and 70.00%, respectively. In addition, the fermentation supernatant played an active role in suppressing the growth of pathogenic fungi. The results of the pot experiment showed that the bacterial fertilizer of the GRY-11 promoted the growth of Malus hupehensis seedlings, improved the activity of protective enzymes in plant roots, enhanced the soil enzyme content, and optimized the soil microbial environment. In general, the GRY-11 can be used as an effective microbial preparation to alleviate ARD. Our study offers novel perspectives for the prevention of ARD.
- MeSH
- Antibiosis MeSH
- Pest Control, Biological * MeSH
- Biological Control Agents * MeSH
- Fusarium growth & development MeSH
- Fungi growth & development MeSH
- Plant Roots microbiology MeSH
- Malus * microbiology growth & development MeSH
- Plant Diseases * microbiology prevention & control MeSH
- Paenibacillus polymyxa * isolation & purification physiology genetics classification MeSH
- Soil Microbiology MeSH
- Rhizosphere MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- China MeSH
In advanced prostate cancer (PC), in particular after acquisition of resistance to androgen receptor (AR) signaling inhibitors (ARSI), upregulation of AR splice variants compromises endocrine therapy efficiency. Androgen receptor splice variant-7 (ARV7) is clinically the most relevant and has a distinct 3' untranslated region (3'UTR) compared to the AR full-length variant, suggesting a unique post-transcriptional regulation. Here, we set out to evaluate the applicability of the ARV7 3'UTR as a therapy target. A common single nucleotide polymorphism, rs5918762, was found to affect the splicing rate and thus the expression of ARV7 in cellular models and patient specimens. Serine/arginine-rich splicing factor 9 (SRSF9) was found to bind to and increase the inclusion of the cryptic exon 3 of ARV7 during the splicing process in the alternative C allele of rs5918762. The dual specificity protein kinase CLK2 interferes with the activity of SRSF9 by regulating its expression. Inhibition of the Cdc2-like kinase (CLK) family by the small molecules cirtuvivint or lorecivivint results in the decreased expression of ARV7. Both inhibitors show potent anti-proliferative effects in enzalutamide-treated or -naive PC models. Thus, targeting aberrant alternative splicing at the 3'UTR of ARV7 by disturbing the CLK2/SRSF9 axis might be a valuable therapeutic approach in late stage, ARSI-resistant PC.
- MeSH
- 3' Untranslated Regions genetics MeSH
- Alternative Splicing genetics drug effects MeSH
- Receptors, Androgen * metabolism genetics MeSH
- Polymorphism, Single Nucleotide genetics MeSH
- Humans MeSH
- Cell Line, Tumor MeSH
- Prostatic Neoplasms * genetics metabolism pathology drug therapy MeSH
- Protein Isoforms genetics metabolism MeSH
- Protein Serine-Threonine Kinases genetics metabolism antagonists & inhibitors MeSH
- Gene Expression Regulation, Neoplastic * drug effects MeSH
- Serine-Arginine Splicing Factors * metabolism genetics MeSH
- RNA Splicing genetics MeSH
- Protein-Tyrosine Kinases * genetics metabolism MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Publication type
- Journal Article MeSH
Hereditární angioedém je vrozené onemocnění charakterizované opakujícími se atakami bolestivých, nesvědivých otoků v dermis a v submukóze, významně snižující kvalitu života. Onemocnění nejčastěji vzniká v důsledku nedostatku C1 inhibitoru či jeho funkčního defektu. Léčbu lze rozdělit na léčbu akutních atak a na profylaxi: krátkodobou (před invazivním výkonem) či dlouhodobou (s cílem dosažení plné kontroly onemocnění a normalizace kvality života nemocných). V posledním desetiletí došlo k významnému rozšíření spektra terapeutických možností, zejména dlouhodobé profylaxe. Prakticky rovnocenně lze v klinické praxi použít Lanadelumab, koncentrát C1 inhibitoru určený s podkožnímu podání, či perorální malou molekulu berotralstat, a tím předcházet vzniku akutních atak. V letošním roce byla dále registrována monoklonální protilátka proti faktoru XII. Ve fázi preklinických a klinických zkoušení se nacházejí další slibné možnosti: cílené malé molekuly (podání profylaktické i on demand), monoklonální protilátky, Léčba na bázi RNA interference, genová terapie a editace.
Hereditary angioedema is an inherited disease characterized by recurrent attacks of painful, non-itchy swelling in the dermis and submucosa, significantly reducing the quality of life. The disease is predominantly caused by a deficiency of C1 inhibitor or its functional defect. Treatment can be divided into treatment of acute attacks and prophylaxis: short-term (before invasive procedures) or long-term (with the aim of achieving full control of the disease and normalizing patients’ quality of life). In the last decade, the spectrum of therapeutic options has significantly expanded, especially long-term prophylaxis. Lanadelumab, a concentrate of serum C1 inhibitor for subcutaneous administration, or orally used the small molecule berotralstat can be used almost equally in clinical practice preventing acute attacks. This year, a monoclonal antibody against factor XII was also registered. Other promising approaches have been in the preclinical and clinical testing phase: targeted small molecules (prophylactic and on demand), monoclonal antibodies, RNA-based therapeutics, gene therapy and editing.
Temporal interference (TI) is a method of non-invasive brain stimulation using transcutaneous electrodes which allows the targeting and modulation of deeper brain structures, not normally associated with non-invasive simulation, while avoiding unwanted stimulation of shallower cortical structures. The properties of TI have been previously demonstrated, however, the problem of decoupling stimulation focality from stimulation intensity has not yet been well addressed. In this paper, we provide a possible novel solution, multipolar TI (mTI), which allows increased independent control over both the size of the stimulated region and the stimulation intensity. The mTI method uses multiple carrier frequencies to create multiple overlapping amplitude-modulated envelopes, rather than using one envelope as in standard TI. The study presents an explanation of the concept of mTI along with experimental data gathered from Rhesus macaques and mice. We improved the focality at depth in anesthetized mice and monkeys, and using the new focality in awake monkeys, evoked targeted activity at depth in the superior colliculus. The mTI method could be an interesting and potentially useful new tool alongside other forms of non-invasive brain stimulation. Teaser Multipolar Temporal Interference Stimulation can produce a more focal brain stimulation at depth compared to Temporal Interference.
- Publication type
- Journal Article MeSH
Defekty pánevního dna u žen jsou velmi rozšířeným problémem. Odhaduje se, že až 11 % žen potřebuje řešit nějakou formu prolapsu pánevních orgánů (POP, Pelvic Organ Prolapse). Jen stěží lze předpokládat, že se bude tento statistický údaj výrazněji měnit. Operační postupy stále procházejí zákonitým vývojem. V minulosti prováděné samostatné kolporafie v dnešní době již nejsou aktuální a kolpokleiza je indikována výjimečně. Významný počet neuspokojivých výsledků po klasických operacích byl příčinou hledání nových chirurgických technologií v této oblasti. Prevalence reoperací v zemích, kde probíhají relevantní klinické studie, je vysoká. Olsen a kol. ve své studii uvádí 29,2% výskyt recidiv, Whiteside v prospektivní studii prezentuje dokonce 58 % recidiv po vaginálních operacích pro POP (1, 2). Zavedení síťkových implantátů do operativy pánevních prolapsů znamenalo zásadní zvrat v této problematice. Síťkové implantáty začaly být užívány při operacích pánevních prolapsů po dobrých zkušenostech se síťkami při řešení břišních kýl a také po přelomových zkušenostech při řešení stresové inkontinence (SI) implantacemi tahuprostých suburetrálních pásek. Přinesly do operativy POP jeden zásadní prvek - schopnost přemostit i velké plošné defekty pojivové tkáně vzniklé porodním traumatem nebo pánevní operací. Jejich použití při operaci POP je však daleko náročnější než při operacích břišních kýl, protože POP je specifickou kýlou v dynamicky náročném prostoru. Při těchto operacích zasahujeme do velmi citlivých funkcí, jakými jsou močení, defekace a sexuální funkce. Jejich zavedení do chirurgické praxe lze jednoznačně považovat za pokrok, přesto že klinické výsledky při jejich používání byly někdy rozpačité. Především se objevily zcela nové typy komplikací, s jejichž řešením nebyly žádné zkušenosti. Přes řadu komplikací při zavádění pánevních implantátů vývoj dosáhl takové úrovně, kdy lze dosahovat prakticky anatomických rekonstrukcí pánevního dna s vynikajícími funkčními výsledky. Pánevní implantáty lze zavádět transvaginálně nebo transabdominálně. U transabdominálního přístupu je aktuální miniinvazivní laparoskopická nebo roboticky asistovaná technologie implantace. Kvalitní rekonstrukci pánevního dna bez použití síťkových implantátů v současné době není možné provést.
Pelvic floor disorders in women are a very common issue. It is estimated that up to 11% of women are experiencing some form of pelvic organ prolapse (POP). It can hardly be assumed that this statistic will change significantly. Operating technologies are still evolving. Separate colporrhaphys performed in the past are no longer relevant and colpocleisis are indicated rarely. A high rate of unsatisfactory outcomes following conventional surgeries has driven the search for new surgical technologies in this area. Reoperation rates are notably high in countries where relevant clinical trials are ongoing. Olsen et al. report a 29.2% incidence of recurrences, while Whiteside et al. present even 58% of recurrences after vaginal surgery for POP in a prospective study (1, 2). The introduction of mesh implants into pelvic prolapse surgery meant a significant turning point in the treatment of this condition. Mesh implants began to be used in pelvic prolapse surgeries following successful experience with meshes in the treatment of abdominal hernias and also after groundbreaking experience in dealing with stress incontinence (SI) through tension-free suburethral tape implantation. They brought one essential element to POP operations - the ability to bridge even large surface defects of connective tissue caused by childbirth trauma or previous pelvic surgeries. However, their use in POP surgery is far more demanding than in abdominal hernia surgery, because POP is a specific type of hernia in a dynamically demanding space. These operations interfere with very sensitive functions such as urination, defecation and sexual function. While their introduction into surgical practice can clearly be considered a progress, the clinical results of their use have sometimes been less satisfactory. New types of complications emerged, and there was initially no experience in managing them. Despite these challenges, the development of pelvic implant technology has progressed to the point where it is possible to achieve practically anatomical reconstructions of the pelvic floor with excellent functional results. Pelvic implants can be inserted transvaginally or transabdominally. In the transabdominal approach, minimally invasive laparoscopic or robot-assisted implantation technology is currently available. A high-quality pelvic floor reconstruction is not possible without the use of mesh implants.
The inherent carbohydrate-binding specificities of human galectins can serve as recognition elements in both biotechnological and biomedical applications. The combination of the carbohydrate-recognition domain (CRD) of galectins fused to peptides or proteins for purification, immobilization, and imaging enables multifunctional utilization within a single protein. We present here a library of color-coded galectin fusion proteins that incorporate a His6-tag, a fluorescent protein, and a SpyCatcher or SpyTag unit to enable immobilization procedures. These galectin fusion proteins exhibit similar binding properties to the non-fused galectins with micromolar apparent binding affinities. N- and C-terminal fusion partners do not interfere with the SpyCatcher/SpyTag immobilization. By applying SpyCatcher/SpyTag-mediated SC-ST-Gal-3 conjugates, we show the stepwise formation of a three-layer ECM-like structure in vitro. Additionally, we demonstrate the SpyCatcher/SpyTag-mediated immobilization of galectins in microgels, which can serve as a transport platform for localized targeting applications. The proof of concept is provided by the galectin-mediated binding of microgels to colorectal cancer cells.
- MeSH
- Color MeSH
- Biocompatible Materials chemistry MeSH
- Galectins * chemistry metabolism MeSH
- Gels chemistry MeSH
- Humans MeSH
- Recombinant Fusion Proteins * chemistry metabolism genetics MeSH
- Protein Binding MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
The hedgehog signaling pathway plays an important role in vertebrate embryonic development, tissue homeostasis, and tumorigenesis. Constitutive activation of Hh signaling in various human tumors leads to GLI-mediated transcription and tumor progression. Based on the preliminary screening of a large library of known triterpenes that exhibited interesting Hh inhibitory activity, we designed and synthesized a new series of triterpenoid analogues containing aromatic heterocyclic substituents at position C-2 to enhance their interference with Hh signaling. In this study, we evaluated the effect of 15 synthesized triterpenoids on cell proliferation and Hh pathway activity in relevant cancer cell lines. Among these compounds, two derivatives, 11a and 11b, both featuring a furan ring at position C-2, demonstrated potent inhibitory effects on proliferation and induced cell death in nonsmall cell lung cancer (NSCLC) and prostate cancer cell lines exhibiting hyper-activated Hh signaling. Moreover, these compounds significantly reduced GLI-mediated transcription in cell-based reporter assays. Detailed immunoblot analyses revealed that compounds 11a and 11b decreased the expression of endogenous GLI1 protein and its target genes associated with tumor progression and proliferation, such as Cyclin D1, N-Myc, and Bcl-2, in A549 and DU-145 cancer cells. These findings suggest that the antiproliferative effects of 11a and 11b are mediated through inhibition of the Hh signaling pathway and are promising candidates for the development of new anticancer therapies targeting Hh-dependent tumors.
- Publication type
- Journal Article MeSH
