enzyme inactivation
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The human body gets exposed to a variety of toxins intentionally or unintentionally on a regular basis from sources such as air, water, food, and soil. Certain toxins can be synthetic, while some are biological. The toxins affect the various parts of the body by activating numerous pro-inflammatory markers, like oxidative stresses, that tend to disturb the normal function of the organs ultimately. Nowadays, people use different types of herbal treatments, viz., herbal drinks that contain different spices for detoxification of their bodies. One such example is turmeric, the most commonly available spice in the kitchen and used across all kinds of households. Turmeric contains curcumin, which is a natural polyphenol. Curcumin is a medicinal compound with different biological activities, such as antioxidant, antineoplastic, anti-inflammatory, and antibacterial. Hence, this review gives a comprehensive insight into the promising potential of curcumin in the detoxification of heavy metals, carbon tetrachloride, drugs, alcohol, acrylamide, mycotoxins, nicotine, and plastics. The review encompasses diverse animal-based studies portraying curcumin's role in nullifying the different toxic effects in various organs of the body (especially the liver, kidney, testicles, and brain) by enhancing defensive signaling pathways, improving antioxidant enzyme levels, inhibiting pro-inflammatory markers activities and so on. Furthermore, this review also argues over curcumin's safety assessment for its utilization as a detoxifying agent.
- MeSH
- akrylamid toxicita MeSH
- antioxidancia farmakologie MeSH
- Curcuma chemie MeSH
- kurkumin * farmakologie chemie MeSH
- lidé MeSH
- metabolická inaktivace MeSH
- mykotoxiny toxicita MeSH
- nikotin MeSH
- oxidační stres účinky léků MeSH
- těžké kovy toxicita MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Fabry disease is an X-linked lysosomal storage disorder that causes accumulation of glycosphingolipids in body tissues and fluids, leading to progressive organ damage and life-threatening complications. It can affect both males and females and can be classified into classic or later-onset phenotypes. The disease severity in females ranges from asymptomatic to the more severe, classic phenotype. Most females are hemizygous and the X-linked inheritance is associated with variable X-activation pattern and residual enzymatic activity. The heterogeneity of clinical presentation in females requires different approaches to diagnosis and management than males. A European group of 7 physicians, experienced in the management of Fabry disease, convened to discuss patient perspectives and published guidelines. The experts discussed the need to focus on psychological treatment in relation to individual coping styles when monitoring targets, and the lack of data supporting the use of plasma globotriaosylsphingosine over enzyme activity in the diagnosis of these patients. It was suggested that the high phenotypic variability in female patients may be related to the dynamic nature of the X-chromosome inactivation process and further understanding of this process could help predict the progression of Fabry disease in females and facilitate timely intervention. Due to the range of disease severity they exhibit, female patients with Fabry disease may require a more individualized treatment approach than males. Despite current recommendations, the experts agreed that early disease-specific treatment initiation in high-risk females could improve clinical outcome.
- MeSH
- Fabryho nemoc * terapie genetika diagnóza MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Succinate dehydrogenase (SDH), formed by four subunits SDHA, SDHB, SDHC, SDHD, and an assembly factor SDHAF2, functions as a key respiratory enzyme. Biallelic inactivation of genes encoding any of the components, almost always in the presence of a germline mutation, causes loss of function of the entire enzyme complex (so-called SDH deficiency) and subsequent development of SDH-deficient neoplasms which include pheochromocytoma/paraganglioma, gastrointestinal stromal tumor, and renal cell carcinoma (RCC). These tumors may occur in the same patient or kindred. SDH-deficient RCC shows distinctive morphological features with vacuolated eosinophilic cytoplasm due to distinctive cytoplasmatic inclusions containing flocculent material. The diagnosis is confirmed by loss of SDHB on immunohistochemistry with positive internal control. The majority of tumors occur in the setting of germline mutations in one of the SDH genes, most commonly SDHB. The prognosis is excellent for low-grade tumors but worse for high-grade tumors with high-grade nuclei, sarcomatoid change, or coagulative necrosis. Awareness of the morphological features and low-threshold for applying SDHB immunohistochemistry help identify patients with SDH-deficient RCC and hereditary SDH-deficient tumor syndromes. In this review we summarize recent development on the clinical and genetic features, diagnostic approach, and pitfalls of SDH-deficient syndrome, focusing on SDH-deficient renal cell carcinomas.
Exokrinní pankreatická nedostatečnost (EPI – exocrine pancreatic insufficiency) je charakterizována nedostatečnou sekrecí pankreatických trávicích enzymů. Dle mechanistické teorie není nedostatkem pankreatických enzymů v tenkém střevě zajištěno trávení potravy, což je spojeno především s nedostatkem esenciálních mastných kyselin a liposolubilních vitaminů a ve svém důsledku vede k neschopnosti zajistit nutriční a metabolické potřeby organizmu. V diagnostice je standardem stanovení fekální elastázy. Toto stanovení je jednoduché, limitací je malá senzitivita stanovit možné změny pankreatické funkce již v tzv. iniciálních stadiích nemoci. Alternativou vyšetření fekální elastázy je použití dechových testů s využitím mixu triglyceridů označených radioaktivně na uhlíku C13. Test je sice neinvazivní, ale časově náročný a obtížněji dostupný. Klinickými symptomy EPI jsou především takové příznaky, které souvisí s mikrobiálním trávením a následnou malabsorbcí/maldigescí mikro- i makronutrientů. Kromě subjektivního pocitu nadýmání, borborygmů nebo osmotického průjmu jsou častým nálezem nízké hladiny liposolubilních vitaminů a některých stopových prvků. Do obrazu EPI patří i osteoporóza nebo sarkopenie. V terapii EPI je zásadním přístupem dietoterapie a substituce pankreatickými enzymy. Zásadou je podání odpovídající dávky především pankreatické lipázy: 40 000–50 000 jednotek k hlavním jídlům, s aplikací během jídla. Menší jídla (svačiny) jsou substituovány poloviční dávkou. Optimální galenickou formou jsou kapsle s ochranným obalem proti inaktivaci enzymů žaludeční kyselinou solnou před jejich vstupem do duodena. Galenickou formou jsou kapsle s obsahem enzymů v mikročásticích o velikosti 1,0–2,0 mm, které se z kapsle uvolní při vstupu do duodena. Jedná se o tzv. řízenou synchronizaci liberalizace enzymů, které obsahuje kapsle. EPI je stavem v populaci poddiagnostikovaným a podléčeným. Kontrola pacientů tak musí zahrnout kromě zhodnocení celkového klinického stavu i sledování změn, které mohou manifestovat malabsorpci. Nutriční stav je doporučeno sledovat alespoň jednou ročně, a to v pravidelných intervalech.
Exocrine pancreatic insufficiency (EPI) is characterized by insufficient secretion of pancreatic digestive enzymes. According to the mechanistic theory, the lack of pancreatic enzymes in the small intestine does not ensure the digestion of food, which is mainly associated with the lack of essential fatty acids and liposoluble vitamins and, as a result, leads to the inability to ensure the nutritional and metabolic needs of the organism. In diagnostics, the standard is determination of fecal elastase. This determination is simple, the limitation is the low sensitivity to determine possible changes in pancreatic function already in the so-called initial stages of the dis ease. An alternative to fecal elastase testing is the use of breath tests using a mixture of triglycerides, radioactively labeled with carbon C13. Although the test is non-invasive, it is time-consuming and more difficult to access. The clinical symptoms of EPI are mainly those related to microbial digestion and subsequent malabsorption/maldigestion of micro- and macronutrients. In addition to the subjective feeling of bloating, borborygmy or osmotic diarrhea, low levels of liposoluble vitamins and some trace elements are frequent findings. Osteoporosis or sarcopenia belong to the picture of EPI. In EPI therapy, diet therapy and pancreatic enzyme replacement are essential approaches. The principle is to administer an adequate dose, especially of pancreatic lipase: 40,000–50,000 units with main meals, with application during meals. Smaller meals (snacks) are substituted with half the dose. The optimal galenic form is capsules with a protective cover, against the inactivation of enzymes by gastric acid, before they enter the duodenum. The galenic form is capsules containing enzymes in microparticles, 1.0–2.0 mm in size, which are released from the capsule upon entering the duodenum. This is the so-called controlled synchronization of the liberalization of the enzymes contained in the capsule. EPI is an underdiagnosed and undertreated condition in the population. The control of patients must therefore include, in addition to the evaluation of the overall clinical condition, the monitoring of changes that may manifest malabsorption. It is recommended to monitor the nutritional status at least once a year, at regular intervals.
Exokrinní pankreatická insuficience je podmíněna nedostatečnou sekrecí pankreatických enzymů ev. jejich předčasnou inaktivací anebo jejich inadekvátní aktivací ve střevě. Hlavní příčinou u dětí je chronická pankreatitida a cystická fibróza. Klinicky se pankreatická malabsorpce projeví neprospíváním, steatoreou s průjmem, azotoreou s poklesem sérového albuminu a proteinů. Cystická fibróza je nejčastějším autozomálně recesivně dědičným onemocněním kavkazské rasy. Onemocnění má charakter multiorgánového postižení. Prognóza velmi závisí na včasné diagnostice a multioborovém léčebném přístupu. Autoři poukazují na stále platný význam potního testu v diagnostice cystické fibrózy prezentací kazuistiky batolete s cystickou fibrózou s negativním novorozeneckým screeningem.
The cause of exocrine pancreatic insufficiency is inadequate secretion of pancreatic enzymes or premature inactivation or inadequate activation in the bowel. The main cause is chronic pancreatitis and cystitic fibrosis. Clinical manifestations of pancreatic malabsorption are weight loss, steatorrhea with diarrehea, azotorhhea, loss of serum albumin and proteins. Cystic fibrosis is the most common autosomal recessive disease of the Caucasian population characterised by chronic multi-organ impairment. Early diagnosis and multi-professional centre care is necessery for optimal management and improved quality of life and survival of patients. The authors point out the importance of the sweat test in diagnosis of cystic fibrosis presentation of a case study of toddler with cystic fibrosis who had a negative newborn screening.
- MeSH
- alergie na mléko diagnóza dietoterapie MeSH
- aminokyseliny terapeutické užití MeSH
- chloridy analýza MeSH
- cystická fibróza * diagnóza komplikace patologie terapie MeSH
- exokrinní pankreatická insuficience * diagnóza etiologie terapie MeSH
- feces enzymologie MeSH
- kojenec MeSH
- lidé MeSH
- novorozenecký screening metody MeSH
- pankreatická elastasa analýza MeSH
- pot chemie MeSH
- potrava pro kojence MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- Publikační typ
- kazuistiky MeSH
BACKGROUND: Xrn1 exoribonuclease is the major mRNA degradation enzyme in Saccharomyces cerevisiae. In exponentially growing cells, Xrn1 is localised in the yeast cells and directs the degradation of mRNA molecules. Xrn1 is gradually deposited and presumably inactivated in the processing bodies (P-bodies) as the yeast population ages. Xrn1 can also localise to the membrane compartment of the arginine permease Can1/eisosome compartment at the yeast plasma membrane. This localisation correlates with the metabolic (diauxic) shift from glucose fermentation to respiration, although the relevance of this Xrn1 localisation remains unknown. METHODS: We monitored the growth rates and morphology of Xrn1-green fluorescent protein (GFP) cells compared to wild-type and Δxrn1 cells and observed the Xrn1-GFP localisation pattern in different media types for up to 72 hours using fluorescence microscopy. RESULTS: We present the dynamic changes in the localisation of Xrn1 as a versatile tool for monitoring the growth of yeast populations at the single-cell level using fluorescence microscopy. CONCLUSIONS: The dynamic changes in the localisation of Xrn1 can be a versatile tool for monitoring the growth of yeast populations at the single-cell level. Simultaneously, Xrn1 localisation outside of P-bodies in post-diauxic cells supports its storage and cytoprotective function, yet the role of P-bodies in cell metabolism has still not yet been entirely elucidated.
The protozoan parasite Trichomonas vaginalis (Tv) causes trichomoniasis, the most common non-viral sexually transmitted infection in the world. Although Tv has been linked to significant health complications, only two closely related 5-nitroimidazole drugs are approved for its treatment. The emergence of resistance to these drugs and lack of alternative treatment options poses an increasing threat to public health, making development of novel anti-Trichomonas compounds an urgent need. The proteasome, a critical enzyme complex found in all eukaryotes has three catalytic subunits, β1, β2, and β5 and has been validated as a drug target to treat trichomoniasis. With the goal of developing tools to study the Tv proteasome, we isolated the enzyme complex and identified inhibitors that preferentially inactivate either one or two of the three catalytic subunits. Using a mass spectrometry-based peptide digestion assay, these inhibitors were used to define the substrate preferences of the β1, β2 and β5 subunits. Subsequently, three model fluorogenic substrates were designed, each specific for one of the catalytic subunits. This novel substrate profiling methodology will allow for individual subunit characterization of other proteasomes of interest. Using the new substrates, we screened a library of 284 peptide epoxyketone inhibitors against Tv and determined the subunits targeted by the most active compounds. The data show that inhibition of the Tv β5 subunit alone is toxic to the parasite. Taken together, the optimized proteasome subunit substrates will be instrumental for understanding the molecular determinants of proteasome specificity and for accelerating drug development against trichomoniasis.
- MeSH
- inhibitory proteasomu farmakologie chemie MeSH
- katalytická doména * MeSH
- proteasomový endopeptidasový komplex * metabolismus chemie MeSH
- protozoální proteiny chemie metabolismus antagonisté a inhibitory genetika MeSH
- substrátová specifita MeSH
- Trichomonas vaginalis * enzymologie MeSH
- Publikační typ
- časopisecké články MeSH
... imprinting: differential expression of maternally and paternally inherited alleles -- X-chromosome inactivation ... ... Phenotype differences arising from genetic variation in drug metabolism 313 -- Genetic variation in enzymes ...
2nd ed. 534 s. : il.
"Genetics and Genomics in Medicine is a new textbook written for undergraduate and graduate students, as well as medical researchers, which explains the science behind the uses of genetics and genomics in medicine today. It is not just about rare inherited and chromosomal disorders, but how genetics affects the whole spectrum of human health and disease. DNA technologies are explained, with emphasis on the modern techniques that have revolutionized the use of genetic information in medicine and are indicating the role of genetics in common complex diseases. The detailed, integrative coverage of genetic approaches to treatment and prevention includes pharmacogenomics and the prospects for personalized medicine. Cancers are essentially genetic diseases and are given a dedicated chapter that includes new insights from cancer genome sequencing. Clinical disorders are covered throughout and there are extensive end-of-chapter questions and problems"--Provided by publisher.
The resistance to carbapenems is usually mediated by enzymes hydrolyzing β-lactam ring. Recently, an alternative way of the modification of the antibiotic, a β-lactone formation by OXA-48-like enzymes, in some carbapenems was identified. We focused our study on a deep analysis of OXA-48-like-producing Enterobacterales, especially strains showing poor hydrolytic activity. In this study, well characterized 74 isolates of Enterobacterales resistant to carbapenems were used. Carbapenemase activity was determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), liquid chromatography/mass spectrometry (LC-MS), Carba-NP test and modified Carbapenem Inactivation Method (mCIM). As meropenem-derived β-lactone possesses the same molecular weight as native meropenem (MW 383.46 g/mol), β-lactonization cannot be directly detected by MALDI-TOF MS. In the spectra, however, the peaks of m/z = 340.5 and 362.5 representing decarboxylated β-lactone and its sodium adduct were detected in 25 out of 35 OXA-48-like producers. In the rest 10 isolates, decarboxylated hydrolytic product (m/z = 358.5) and its sodium adduct (m/z = 380.5) have been detected. The peak of m/z = 362.5 was detected in 3 strains co-producing OXA-48-like and NDM-1 carbapenemases. The respective signal was identified in no strain producing class A or class B carbapenemase alone showing its specificity for OXA-48-like carbapenemases. Using LC-MS, we were able to identify meropenem-derived β-lactone directly according to the different retention time. All strains with a predominant β-lactone production showed negative results of Carba NP test. In this study, we have demonstrated that the strains producing OXA-48-like carbapenemases showing false-negative results using Carba NP test and MALDI-TOF MS preferentially produced meropenem-derived β-lactone. We also identified β-lactone-specific peak in MALDI-TOF MS spectra and demonstrated the ability of LC-MS to detect meropenem-derived β-lactone.
- MeSH
- antibakteriální látky farmakologie MeSH
- bakteriální proteiny * analýza MeSH
- beta-laktamasy analýza MeSH
- Enterobacteriaceae * MeSH
- karbapenemy farmakologie MeSH
- meropenem farmakologie MeSH
- mikrobiální testy citlivosti MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice metody MeSH
- Publikační typ
- časopisecké články MeSH
Zanubrutinib (ZAN) is a Bruton's tyrosine kinase inhibitor recently approved for the treatment of some non-Hodgkin lymphomas. In clinical trials, ZAN is often combined with standard anthracycline (ANT) chemotherapy. Although ANTs are generally effective, drug resistance is a crucial obstacle that leads to treatment discontinuation. This study showed that ZAN counteracts ANT resistance by targeting aldo-keto reductase 1C3 (AKR1C3) and ATP-binding cassette (ABC) transporters. AKR1C3 catalyses the transformation of ANTs to less potent hydroxy-metabolites, whereas transporters decrease the ANT-effective concentrations by pumping them out of the cancer cells. In our experiments, ZAN inhibited the AKR1C3-mediated inactivation of daunorubicin (DAUN) at both the recombinant and cellular levels. In the drug combination experiments, ZAN synergistically sensitised AKR1C3-expressing HCT116 and A549 cells to DAUN treatment. Gene induction studies further confirmed that ZAN did not increase the intracellular level of AKR1C3 mRNA; thus, the drug combination effect is not abolished by enzyme induction. Finally, in accumulation assays, ZAN was found to interfere with the DAUN efflux mediated by the ABCB1, ABCG2, and ABCC1 transporters, which might further contribute to the reversal of ANT resistance. In summary, our data provide the rationale for ZAN inclusion in ANT-based therapy and suggest its potential for the treatment of tumours expressing AKR1C3 and/or the above-mentioned ABC transporters.
- Publikační typ
- časopisecké články MeSH
