Zosuquidar (LY335979) is a widely used experimental P-glycoprotein (P-gp) inhibitor, which is commended as very potent but also as very specific for P-gp. In this in vitro and in silico study, we demonstrated for the first time that zosuquidar also inhibits organic cation transporters (OCT) 1-3, albeit less potently than P-gp. This still has to be kept in mind when zosuquidar is used to inhibit cellular efflux of P-gp substrates that are concurrently transported into the cells by OCTs. To avoid interference in these assays, zosuquidar concentrations should be kept below 1 μM.
- MeSH
- Quinolines * pharmacology MeSH
- Dibenzocycloheptenes MeSH
- HEK293 Cells MeSH
- Humans MeSH
- ATP Binding Cassette Transporter, Subfamily B, Member 1 * antagonists & inhibitors MeSH
- Organic Cation Transport Proteins * antagonists & inhibitors metabolism MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
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.
Bacillus is well known for producing a wide range of compounds that inhibit microbial phytopathogens. From this perspective, we were interested in evaluating the biocontrol potential of 5 plant growth-promoting rhizobacteria Bacillus species (PGPR-Bacillus) on 21 microbial pectinolytic plant pathogens isolated from previous studies. Phytopathogenicity and in vivo biocontrol potential of PGPR curative and preventive treatments were investigated from this angle. Overall, the pathogenicity test on healthy tomato, zucchini, and mandarin showed low rot to no symptoms for all PGPR strain culture treatments. Conversely, zucchini pre-treated with PGPR strains B. circulans and B. cereus for 72 h showed no signs of soft rot and remained healthy when in vitro contaminated with phytopathogens (Neisseria cinerea and Pichia anomala). Additionally, the PGPR-Bacillus strains were shown to be effective in mitigating the symptoms of soft rot in tomatoes, zucchini, and oranges using in vivo curative treatment. It is true that the majority of pectinolytic phytopathogenic strains exhibited antibiotic resistance. In vivo tests revealed that PGPR-Bacillus cell culture was effective against plant pathogens. Thus, PGPR-Bacillus can be considered a potential biocontrol agent for pectinolytic plant pathogens.
- MeSH
- Antibiosis * MeSH
- Bacillus * physiology MeSH
- Pest Control, Biological * methods MeSH
- Biological Control Agents * MeSH
- Citrus microbiology growth & development MeSH
- Plant Diseases * microbiology prevention & control MeSH
- Pectins metabolism MeSH
- Soil Microbiology MeSH
- Solanum lycopersicum microbiology growth & development MeSH
- Plant Development MeSH
- Publication type
- Journal Article MeSH
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
Kratom (Mitragyna speciosa) obsahuje více než 40 různých alkaloidů, hlavními psychoaktivními látkami jsou mitragynin a 7-hydroxymitragynin. Mitragynin a 7-hydroxymitragynin interagují s opioidními receptory, stejně jako adrenergními, serotoninergními a dopaminergními systémy. Kratom je užíván při substituční terapii drogových závislostí, terapii chronických bolestí i jako stimulační látka. Pozitivní účinek bývá popisován i při zvládání úzkostných poruch. Kratom vyvolává toleranci i závislost, jeho užívání není prosté nežádoucích účinků, včetně hepatotoxicity, kardiovaskulárních nežádoucích účinků, vyvolání epileptických záchvatů, popsána jsou úmrtí v důsledku užívání kratomu. Rozvoj nežádoucích účinků a fatálních následků je obvykle spjat s užíváním více účinných látek, např. kombinace s alkoholem nebo dalšími drogami. Kratom zasahuje do metabolismu současně užívané medikace, i zde jsou popsány fatální následky.
Kratom (Mitragyna speciosa) contains more than 40 different alkaloids, the main psychoactive substances being mitragynine and 7-hydroxymitragynine. Mitragynine and 7-hydroxymitragynine interact with opioid receptors as well as adrenergic, serotonergic, and dopaminergic systems. Kratom is used in drug addiction replacement therapy, chronic pain therapy, and as a stimulant. Positive effects have also been described in the management of anxiety disorders. Kratom induces tolerance and dependence, and its use is not without adverse effects, including hepatotoxicity, cardiovascular side effects, the triggering of epileptic seizures, and deaths associated with kratom use have been reported. The development of adverse effects and fatal consequences is usually associated with the use of multiple active substances, e.g., in combination with alcohol or other drugs. Kratom interferes with the metabolism of concurrently used medications, and fatal consequences have also been reported.
Cognitive flexibility (CF) is the ability to adapt cognitive strategies according to the changing environment. The deficit in CF has often been linked to various neurological and psychiatric disorders including schizophrenia. However, the operationalization and assessment of CF have not been unified and the current research suggests that the available instruments measure different aspects of CF. The main objective of the present study was to compare three frequently used neuropsychological measures of CF-Wisconsin Card Sorting Test (WCST), Trail Making Test (TMT) and Stroop Color and Word Test (SCWT) in a population of patients (N = 220) with first-episode schizophrenia spectrum disorders in order to evaluate their convergent validity. The hypothesis of an underlying latent construct was tested via a confirmatory factor analysis. We used a one-factor CF model with scores from WCST, SCWT and TMT as observed variables. The established model showed a good fit to the data (χ2 = 1.67, p = 0.43, SRMR = 0.02, RMSEA = 0.0, CFI = 1.00). The highest factor loading was found in WCST as CF explained most of the variance in this neuropsychological measure compared to the other instruments. On the other hand, a TMT ratio index and a SCWT interference demonstrated lowest loadings in the model. The findings suggest that not all the frequently used measures share an underlying factor of CF or may capture different aspects of this construct.
- MeSH
- Adult MeSH
- Executive Function * physiology MeSH
- Factor Analysis, Statistical MeSH
- Cognitive Dysfunction * etiology diagnosis physiopathology MeSH
- Cognitive Flexibility MeSH
- Middle Aged MeSH
- Humans MeSH
- Adolescent MeSH
- Young Adult MeSH
- Neuropsychological Tests * standards MeSH
- Psychometrics MeSH
- Schizophrenic Psychology * MeSH
- Schizophrenia * complications physiopathology MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Adolescent MeSH
- Young Adult MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
Current antibiotics and chemotherapeutics are becoming ineffective because pathogenic bacteria and tumor cells have developed multiple drug resistance. Therefore, it is necessary to find new substances that can be used in treatment, either alone or as sensitizing molecules in combination with existing drugs. Peptaibols are bioactive, membrane-active peptides of non-ribosomal origin, mainly produced by filamentous fungi such as Trichoderma spp. This study focused on producing peptaibol-rich extracts from Trichoderma atroviride O1, cultivated on malt extract agar (MA) under circadian and constant darkness conditions for 13 days. Peptaibol production was detected by MALDI-TOF mass spectrometry after six days of cultivation. The extracts demonstrated antibacterial activity against Staphylococcus aureus strains, particularly the methicillin-resistant variant, but not against the Gram-negative Pseudomonas aeruginosa. Quorum sensing interference revealed that a peptaibol-rich extract suppressed Vibrio campbellii BAA-1119's AI-2 signaling system to a degree comparable with gentamycin. Beyond antibacterial properties, the extracts exhibited notable antiproliferative activity against human ovarian cancer cells and their adriamycin-resistant subline in both 2D and 3D models. Specifically, MA-derived extracts reduced ovarian cancer cell viability by 70% at 50 μg/mL, especially under light/dark regime of cultivation. Compared to previously published results for PDA-based extracts, MA cultivation shifted the biological effects of peptaibol-containing extracts toward anticancer potential. These findings support the idea that modifying fungal cultivation parameters, the bioactivity of secondary metabolite mixtures can be tailored for specific therapeutic applications.
- MeSH
- Agar * chemistry MeSH
- Anti-Bacterial Agents * pharmacology metabolism MeSH
- Hypocreales MeSH
- Culture Media chemistry MeSH
- Humans MeSH
- Microbial Sensitivity Tests MeSH
- Cell Line, Tumor MeSH
- Peptaibols * pharmacology metabolism biosynthesis chemistry MeSH
- Cell Proliferation drug effects MeSH
- Antineoplastic Agents * pharmacology metabolism MeSH
- Pseudomonas aeruginosa drug effects MeSH
- Staphylococcus aureus drug effects MeSH
- Trichoderma * metabolism growth & development chemistry MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
