Recently, we have identified a recessive mutation, an abnormal coat appearance in the BXH6 strain, a member of the HXB/BXH set of recombinant inbred (RI) strains. The RI strains were derived from the spontaneously hypertensive rat (SHR) and Brown Norway rat (BN-Lx) progenitors. Whole genome sequencing of the mutant rats identified the 195875980 G/A mutation in the tuftelin 1 (Tuft1) gene on chromosome 2, which resulted in a premature stop codon. Compared with wild-type BXH6 rats, BXH6-Tuft1 mutant rats exhibited lower body weight due to reduced visceral fat and ectopic fat accumulation in the liver and heart. Reduced adiposity was associated with decreased serum glucose and insulin and increased insulin-stimulated glycogenesis in skeletal muscle. In addition, mutant rats had lower serum monocyte chemoattractant protein-1 and leptin levels, indicative of reduced inflammation. Analysis of the liver proteome identified differentially expressed proteins from fatty acid metabolism and β-oxidation, peroxisomes, carbohydrate metabolism, inflammation, and proteasome pathways. These results provide evidence for the important role of the Tuft1 gene in the regulation of lipid and glucose metabolism and suggest underlying molecular mechanisms.NEW & NOTEWORTHY A new spontaneous mutation, abnormal hair appearance in the rat, has been identified as a nonfunctional tuftelin 1 (Tuft1) gene. The pleiotropic effects of this mutation regulate glucose and lipid metabolism. Analysis of the liver proteome revealed possible molecular mechanisms for the metabolic effects of the Tuft1 gene.
- MeSH
- glukosa * metabolismus MeSH
- inzulin metabolismus MeSH
- krysa rodu rattus MeSH
- metabolismus lipidů genetika MeSH
- nesmyslný kodon * genetika MeSH
- potkani inbrední BN MeSH
- potkani inbrední SHR MeSH
- proteom metabolismus MeSH
- zánět MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Mucocele of the appendix and pseudomyxoma peritonei are rare diseases. The clinical findings are nonspecific in the early stages of the disease. The sequelae of appendiceal mucocele, its perforation, and extensive peritoneal involvement via pseudomyxoma peritonei (jelly belly) are repeatedly described in the literature. We present the typical findings in the natural history of the disease.
- Publikační typ
- časopisecké články MeSH
Maximal athletic performance can be limited by various factors, including restricted respiratory function. These limitations can be mitigated through targeted respiratory muscle training, as supported by numerous studies. However, the full potential of respiratory training in competitive finswimming has not been fully investigated. This case study aims to evaluate the effects of eight-week respiratory muscle training (RMT) on performance variability during the underwater phases of a 200 m bi-fins race simulation in an elite finswimmer (current world record holder and multiple world championship medalist). Performance variability was assessed based on pre-test, inter-test, and post-test data. Each measurement included pulmonary function and swim performance evaluations. In this study, underwater performance parameters, such as distance, time, velocity, and number of kicks, were assessed using video analysis synchronized with race timing and evaluated using the Dartfish software. The swimmer followed a 28-day training program with an Airofit PROTM respiratory trainer between tests, with daily sessions targeting both inspiratory and expiratory muscles. The training involved 6-10 min of targeted exercises per day. Significant improvements were observed in Wilcoxon's paired-sample test between the pre-test and post-test results in terms of underwater distance (p = 0.012; d = 1.26), underwater time (p = 0.012; d = 1.26), and number of underwater kicks (p = 0.043; d = 1.01), resulting in a 14.23% longer underwater distance, 14.08% longer underwater time, and 14.94% increase in underwater kicks. Despite the increased distance and time, underwater velocity remained stable, indicating improved underwater performance efficiency. Despite some improvements, it is not possible to conclude that respiratory muscle training (RMT) can contribute to improved finswimming performance during the underwater phases of a 200 m bi-fins race simulation in this particular athlete's case. Further research with a larger sample size is necessary to fully understand the impact of RMT on finswimming performance.
- Publikační typ
- časopisecké články MeSH
Recent research has highlighted the pivotal role of lipoxygenases in modulating ferroptosis and immune responses by catalyzing the generation of lipid peroxides. However, the limitations associated with protein enzymes, such as poor stability, low bioavailability, and high production costs, have motivated researchers to explore biomimetic materials with lipoxygenase-like activity. Here, we report the discovery of lipoxygenase-like two-dimensional (2D) MoS2nanosheets capable of catalyzing lipid peroxidation and inducing ferroptosis. The resulting catalytic products were successfully identified using mass spectrometry and a luminescent substrate. Unlike native lipoxygenases, MoS2 nanosheets exhibited exceptional catalytic activity at extreme pH, high temperature, high ionic strength, and organic solvent conditions. Structure-activity relationship analysis indicates that sulfur atomic vacancy sites on MoS2 nanosheets are responsible for their catalytic activity. Furthermore, the lipoxygenase-like activity of MoS2 nanosheets was demonstrated within mammalian cells and animal tissues, inducing distinctive ferroptotic cell death. In summary, this research introduces an alternative to lipoxygenase to regulate lipid peroxidation in cells, offering a promising avenue for ferroptosis induction.
- MeSH
- biomimetické materiály chemie farmakologie metabolismus MeSH
- disulfidy * chemie metabolismus MeSH
- ferroptóza * účinky léků MeSH
- katalýza MeSH
- lidé MeSH
- lipoxygenasa * metabolismus chemie MeSH
- molybden chemie metabolismus MeSH
- myši MeSH
- nanostruktury chemie MeSH
- peroxidace lipidů MeSH
- vztahy mezi strukturou a aktivitou MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
MICAL proteins play a crucial role in cellular dynamics by binding and disassembling actin filaments, impacting processes like axon guidance, cytokinesis, and cell morphology. Their cellular activity is tightly controlled, as dysregulation can lead to detrimental effects on cellular morphology. Although previous studies have suggested that MICALs are autoinhibited, and require Rab proteins to become active, the detailed molecular mechanisms remained unclear. Here, we report the cryo-EM structure of human MICAL1 at a nominal resolution of 3.1 Å. Structural analyses, alongside biochemical and functional studies, show that MICAL1 autoinhibition is mediated by an intramolecular interaction between its N-terminal catalytic and C-terminal coiled-coil domains, blocking F-actin interaction. Moreover, we demonstrate that allosteric changes in the coiled-coil domain and the binding of the tripartite assembly of CH-L2α1-LIM domains to the coiled-coil domain are crucial for MICAL activation and autoinhibition. These mechanisms appear to be evolutionarily conserved, suggesting a potential universality across the MICAL family.
- MeSH
- aktiny metabolismus chemie MeSH
- alosterická regulace MeSH
- calponiny MeSH
- elektronová kryomikroskopie * MeSH
- lidé MeSH
- mikrofilamenta metabolismus ultrastruktura MeSH
- mikrofilamentové proteiny metabolismus chemie ultrastruktura MeSH
- molekulární modely MeSH
- oxygenasy se smíšenou funkcí MeSH
- proteinové domény MeSH
- proteiny s doménou LIM metabolismus chemie genetika MeSH
- vazba proteinů * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Osteoporóza (OP) je systémové metabolické onemocnění charakterizované sníženým obsahem kostní hmoty a narušením mikroarchitektury kosti, což je příčinou zvýšené fragility kosti, a tím zvýšeného rizika zlomenin již při minimálním traumatu. Cílem léčby osteoporózy je restituce prořídlé kostní tkáně. Konečným a hlavním cílem je prevence zlomenin. Podle toho je možno také posuzovat účinnost léčby. Časnějším, nepřímým ukazatelem úspěšnosti léčby je zvýšení kostní denzity, nebo alespoň zpomalení jejího úbytku na fyziologickou hranici. Sklerostin je protein, který je u lidí kódován genem SOST. Sklerostin je produkován především osteocyty, má antianabolické účinky na novotvorbu kostí. Romosozumab je humanizovaná monoklonální protilátka IgG2 proti sklerostinu. Vývoj protilátky proti sklerostinu se jevil ideálním k ovlivnění novotvorby kosti právě pro téměř výhradní expresi genu SOST v kosti. Romosozumab se ukázal jako mimořádně účinný při zvyšování denzity kostního minerálu (BMD), modulaci markerů kostního obratu a redukci rizika fraktur. Při léčbě romosozumabem dochází k rychlému a účinnému snížení rizika zlomenin u postmenopauzálních žen s osteoporózou. Dvojí mechanizmus účinku činí z romosozumabu jedinečnou a účinnou možnost léčby osteoporózy, zejména v případech, v nichž je žádoucí rychlé navýšení denzity kostí. Významné snížení rizika zlomenin představuje podstatný klinický přínos.
Osteoporosis (OP) is a systemic metabolic disease characterized by reduced bone mass and disturbed bone microarchitecture, which causes increased bone fragility and thus increased risk of fractures even with minimal trauma. The goal of osteoporosis treatment is restitution of thinned bone tissue. The ultimate and main goal is fracture prevention. The effectiveness of treatment can also be judged accordingly. An early, indirect indicator of the success of treatment is an increase in bone density, or at least a slowing of bone loss to the physiological limit. Sclerostin is a protein that in humans is encoded by the SOST gene. Sclerostin is produced mainly by osteocytes and has antianabolic effects on bone formation. Romosozumab is a humanized IgG2 monoclonal antibody against sclerostin. The development of an antibody against sclerostin seemed ideal to affect bone formation precisely because of the almost exclusive expression of the SOST gene in bone. Romosozumab has proven to be extremely effective in increasing bone mineral density (BMD), modulating markers of bone turnover and reducing fracture risk. Treatment with romosozumab results in a rapid and effective reduction in fracture risk in postmenopausal women with osteoporosis. The dual mechanism of action makes romosozumab a unique and effective treatment option for osteoporosis, particularly in cases where rapid increases in bone density are desired. The significant reduction in fracture risk represents a substantial clinical benefit.
- Klíčová slova
- romosozumab,
- MeSH
- inhibitory kostní resorpce terapeutické užití MeSH
- klinické zkoušky jako téma MeSH
- kortikální kost účinky léků ultrastruktura MeSH
- kostní denzita účinky léků MeSH
- lidé MeSH
- monoklonální protilátky * terapeutické užití MeSH
- nežádoucí účinky léčiv MeSH
- osteoporotické fraktury prevence a kontrola MeSH
- osteoporóza * diagnóza farmakoterapie prevence a kontrola MeSH
- remodelace kosti účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- grafy a diagramy MeSH
- přehledy MeSH
- Klíčová slova
- romosozumab,
- MeSH
- kardiovaskulární nemoci epidemiologie patofyziologie MeSH
- klinické zkoušky jako téma MeSH
- lidé MeSH
- monoklonální protilátky * škodlivé účinky terapeutické užití MeSH
- osteoporóza farmakoterapie komplikace patofyziologie MeSH
- rizikové faktory kardiovaskulárních chorob * MeSH
- Check Tag
- lidé MeSH
Signální dráha receptoru pro epidermální růstový faktor (EGFR) se podílí na regulaci buněčných funkcí osteoklastů i osteoblastů. Útlum signalizace v této dráze aplikací inhibitorů tyrozinkinázy (EGFR-TKI) je využíván jako varianta protinádorové terapie u pacientů s nemalobuněčným karcinomem plic (NSCLC) s aktivačními mutacemi genu EGFR. Popisujeme případ pacientky s NSCLC léčené afacitinibem, u níž jsme pozorovali významnou supresi kostní remodelace doprovázenou vzestupem BMD, která byla dále potencována navazující aplikací denosumabu. Vliv inhibice EGFR-TKI na kostní metabolizmus není dostatečně prostudován. In vitro data ukazují, že inhibice EGFR vede k útlumu aktivity osteoblastů i osteoklastů. Další výzkum je žádoucí i s ohledem na významné přesahy do klinické praxe – kostní metastázy, nádorová postižení skeletu (SRE), osteonekróza čelisti (ONJ).
The EGFR signaling pathway is involved in the regulation of cellular functions of osteoclasts and osteoblasts. Suppression of signaling in this pathway by administration of EGFR-TKIs has been used as an option for anticancer therapy in NSCLC patients with activating mutations of the EGFR gene. We describe the case of an NSCLC patient treated with afacitinib in whom we observed a significant suppression of bone remodeling accompanied by an increase in BMD, which was further potentiated by downstream administration of denosumab. The effect of EGFR-TKI inhibition on bone metabolism has not been sufficiently studied. In vitro data show that EGFR inhibition leads to attenuation of osteoblast and osteoclast activity. Further research is also desirable in view of important overlaps into clinical practice (bone metastases, Skeletal-Related Events, OsteoNecrosis of the Jaw).
- MeSH
- afatinib * aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- denosumab aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- fatální výsledek MeSH
- geny erbB-1 účinky léků MeSH
- inhibitory kostní resorpce aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- inhibitory tyrosinkinasy aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- kostní denzita účinky léků MeSH
- lidé MeSH
- nemalobuněčný karcinom plic * komplikace terapie MeSH
- remodelace kosti * účinky léků MeSH
- senioři MeSH
- Check Tag
- lidé MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
