Digestive enzyme Dotaz Zobrazit nápovědu
Probiotika jsou nepatogenní mikroorganizmy většinou lidského původu, které aplikovány v přiměřeném množství příznivě ovlivňují zdravotní stav hostitele a umožňují předejít nebo zlepšit některé choroby.Probiotika mohou být dočasnou součástí střevní mikroflóry, ale jejich množství není dostatečné pro terapeutické účely. Činnost střevní mikroflóry (včetně probiotických kmenů) vyžaduje přítomnost nutričních substrátů (prebiotik), tj. různých druhů vlákniny a oligosacharidů. Prebiotika jsou štěpena mikrobiálními enzymy za vzniku látek nezbytných pro metabolizmus a funkce střevní sliznice. Probiotika vykazují řadu příznivých účinků, které opravňují jejich terapeutické použití. Za tím účelem musí probiotika splnit řadu požadavků dokládajících jejich účinnost a bezpečnost. Použití probiotik u chorob trávicího ústrojí se zakládá na experimentálních a klinických studiích u idiopatických střevních zánětů, infekčních a postantibiotických enterokolitid, syndromu dráždivého střeva, jaterních chorob a některých dalších afekcí. Probiotická terapie má fyziologický charakter a její bezpečnost je vysoká. Tato koncepce přináší nové terapeutické možnosti u řady chorob trávicího ústrojí a její význam se bude zvyšovat s přibývajícími poznatky a zkušenostmi.
Probiotics are nonpathogenic microorganisms mostly of human origin which, when administered in adequate amounts confer a health benefit on the host and enable to prevent or improve some diseases. Probiotics may constitute a temporary component of intestinal microflora, but their concentration is not sufficient for therapeutic purposes. The viability of intestinal microflora (including probiotic strains) requires the availability of nutritional substrates (prebiotics), i.e. various types of fiber and oligosaccharides. Prebiotics are cleaved by microbial enzymes to various substances indispensable for metabolic and functional activities of the intestinal mucosa. Probiotics display favourable effects which qualify them for therapeutic use. For this purpose probiotics have to fulfil a series of requirements verifying their efficacy and safety. The administration of probiotics in digestive diseases is substantiated by experimental and clinical studies in inflammatory bowel diseases, infective and postantibiotic colitides, irritable bowel syndrome, liver diseases and some other conditions. Probiotic therapy has a physiologic character and its safety is high. This therapeutic concept opens new possibilities in a couple of digestive diseases and its importance will increase with growing knowledge and experience.
- MeSH
- finanční podpora výzkumu jako téma MeSH
- idiopatické střevní záněty diagnóza etiologie terapie MeSH
- lidé MeSH
- nemoci trávicího systému diagnóza etiologie terapie MeSH
- oligosacharidy aplikace a dávkování farmakologie chemie MeSH
- potravní vláknina aplikace a dávkování farmakologie terapeutické užití MeSH
- přehledová literatura jako téma MeSH
- probiotika aplikace a dávkování farmakologie terapeutické užití MeSH
- Check Tag
- lidé MeSH
Vzácnou příčinou krvácení do trávicí trubice v průběhu pankreatitidy je natrávení stěny střevní pankreatickými enzymy. Autoři probírají patogenezi, diagnostiku i terapii této komplikace na příkladu nemocného s tryptickou lézí levého tračníku. Současně bylo prokázáno krvácení do pseudocysty kaudy pankreatu a do perirenálního prostoru.
A rare cause of haemorrhage into the digestive tract in pancreatitis is partial digestion of the intestinal wall by pancreatic enzymes. The authors discuss the pathogenesis, diagnosis and therapy of this complication on the example of a patient with a tryptic lesion of the colon. At the same time they detected haemorrhage into pseudocyst of the pancreatic cauda and into the prerenal space.
This study examined the effect of two natural toxins (a venom from the parasitic wasp Habrobracon hebetor and destruxin A from the entomopathogenic fungus Metarhizium anisopliae), and one pathogen (the entomopathogenic fungus Isaria fumosorosea) on the activity of basic digestive enzymes in the midgut of the cockroach Periplaneta americana. Simultaneously, the role of adipokinetic hormones (AKH) in the digestive processes was evaluated. The results showed that all tested toxins/pathogens elicited stress responses when applied into the cockroach body, as documented by an increase of AKH level in the central nervous system. The venom from H. hebetor showed no effect on digestive enzyme activities in the ceca and midgut in vitro. In addition, infection by I. fumosorosea caused a decrease in activity of all enzymes in the midgut and a variable decrease in activity in the ceca; application of AKHs did not reverse the inhibition. Destruxin A inhibited the activity of all enzymes in the midgut but none in the ceca in vitro; application of AKHs did reverse this inhibition, and no differences between both cockroach AKHs were found. Overall, the results demonstrated the variable effect of the tested toxins/pathogens on the digestive processes of cockroaches as well as the variable ability of AKH to counteract these effects.
- MeSH
- aktivace enzymů MeSH
- depsipeptidy toxicita MeSH
- gastrointestinální trakt enzymologie MeSH
- hmyzí hormony farmakologie MeSH
- kyselina pyrrolidonkarboxylová analogy a deriváty farmakologie MeSH
- oligopeptidy farmakologie MeSH
- Periplaneta účinky léků enzymologie MeSH
- vosí jedy toxicita MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Klíčová slova
- KREON (SOLVAY PHARMA GMBH),
- MeSH
- dospělí MeSH
- enzymoterapie MeSH
- enzymy aplikace a dávkování MeSH
- exokrinní pankreatická insuficience terapie MeSH
- lidé středního věku MeSH
- lidé MeSH
- metabolismus sacharidů MeSH
- proteiny metabolismus MeSH
- sacharidy MeSH
- trávení MeSH
- tuky metabolismus MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
The Colorado potato beetle (CPB), Leptinotarsa decemlineata, is a major pest of potato plants, and its digestive system is a promising target for development of pest control strategies. This work focuses on functional proteomic analysis of the digestive proteolytic enzymes expressed in the CPB gut. We identified a set of peptidases using imaging with specific activity-based probes and activity profiling with selective substrates and inhibitors. The secreted luminal peptidases were classified as: (i) endopeptidases of cathepsin D, cathepsin L, and trypsin types and (ii) exopeptidases with aminopeptidase (cathepsin H), carboxypeptidase (serine carboxypeptidase, prolyl carboxypeptidase), and carboxydipeptidase (cathepsin B) activities. The proteolytic arsenal also includes non-luminal peptidases with prolyl oligopeptidase and metalloaminopeptidase activities. Our results indicate that the CPB gut employs a multienzyme network of peptidases with complementary specificities to efficiently degrade ingested proteins. This proteolytic system functions in both CPB larvae and adults and is controlled mainly by cysteine and aspartic peptidases and supported by serine and metallopeptidases. The component enzymes identified here are potential targets for inhibitors with tailored specificities that could be engineered into potato plants to confer resistance to CPB.
- MeSH
- brouci enzymologie genetika růst a vývoj metabolismus MeSH
- fyziologie výživy zvířat MeSH
- gastrointestinální trakt enzymologie MeSH
- hmyzí proteiny genetika metabolismus MeSH
- larva genetika růst a vývoj metabolismus MeSH
- proteasy genetika metabolismus MeSH
- proteolýza MeSH
- proteomika MeSH
- rostlinné proteiny metabolismus MeSH
- trávení MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Temperature and food quality are the most important environmental factors determining the performance of herbivorous insects. The objective of our study was to evaluate the responses of the spongy moth (formerly known as the gypsy moth) [Lymantria dispar L. (Lepidoptera: Erebidae)] to simultaneous variation in these two factors. From hatching to the fourth instar, larvae were exposed to three temperatures (19 °C, 23 °C, and 28 °C) and fed four artificial diets that differed in protein (P) and carbohydrate (C) content. Within each temperature regime, the effects of the nutrient content (P+C) and ratio (P:C) on development duration, larval mass, growth rate, and activities of digestive proteases, carbohydrases, and lipase were examined. It was found that temperature and food quality had a significant effect on the fitness-related traits and digestive physiology of the larvae. The greatest mass and highest growth rate were obtained at 28 °C on a high-protein low-carbohydrate diet. A homeostatic increase in activity was observed for total protease, trypsin, and amylase in response to low substrate levels in the diet. A significant modulation of overall enzyme activities in response to 28 °C was detected only with a low diet quality. A decrease in the nutrient content and P:C ratio only affected the coordination of enzyme activities at 28 °C, as indicated by the significantly altered correlation matrices. Multiple linear regression analysis showed that variation in fitness traits in response to different rearing conditions could be explained by variation in digestion. Our results contribute to the understanding of the role of digestive enzymes in post-ingestive nutrient balancing.
Škrob je biopolymer, obsažený v rostlinách a řasách. V zelených rostlinách se tvoří při fotosyntéze v chloroplastech jako tzv. tranzitní škrob, který je v průběhu temné fáze transportován v podobě rozpustných sacharidů do zásobních orgánů rostlin, kde je opět převe‐ den do podoby škrobových zrn. Tato opětná syntéza se liší pro jednoděložné a dvouděložné rostliny. Průmyslově izolovaný škrob má řadu využití, hlavní roli hraje enzymová hydrolýza na sirupy, které pak mohou být výchozí látkou pro celou řadu dalších biochemických transformací. Článek se věnuje rovněž nutričním aspektům škrobu, především jeho stravitelností. Je popsán základní princip enzymo‐ vých metod ke stanovení obsahu celkového škrobu, obsahu amylosy, rychle a pomalu stravitelného škrobu a škrobu rezistentního.
Starch is a biopolymer found in plants and algae. In green plants, it is formed during photosynthesis in the chloroplasts as so ‐called transitory starch, which is transported during the dark phase in the form of soluble carbohydrates to the storage organs of plants, where it is again converted into the form of starch granules. This repeated synthesis is different for monocots and dicots. Industria‐ lly isolated starch has a number of uses, the main role is played by enzyme hydrolysis into syrups, which can then be the starting material for a whole range of subsequent biochemical transformations. The article also deals with the nutritional aspects of starch, especially its digestibility. The basic principle of enzyme methods to determine the content of total starch, amylose content, rapidly and slowly digestible starch and resistant starch is described.
Millipedes represent a model for the study of organic matter transformation, animal-microbial interactions, and compartmentalisation of digestion. The activity of saccharidases (amylase, laminarinase, cellulase, xylanase, chitinase, maltase, cellobiase, and trehalase) and protease were measured in the midgut and hindgut contents and walls of the millipedes Archispirostreptus gigas and Epibolus pulchripes. Assays done at pH 4 and 7 confirmed activities of all enzymes except xylanase. Hydrolysing of starch and laminarin prevailed. The hindgut of E. pulchripes was shorter, less differentiated. Micro-apocrine secretion was observed only in the midgut of A. gigas. Merocrine secretion was present in midgut and hindgut of E. pulchripes, and in the pyloric valve and anterior hindgut of A. gigas. Alpha-polysaccharidases were mostly active in the midgut content and walls, with higher activity at pH 4. The low activity of amylase (A. gigas) and laminarinase (E. pulchripes) in midgut tissue may indicate their synthesis in salivary glands. Cellulases were found in midgut. Chitinases, found in midgut content and tissue (E. pulchripes) or concentrated in the midgut wall (A. gigas), were more active at an acidic pH. Polysaccharidases were low in hindguts. Protease shows midgut origin and alkaline activity extending to the hindgut in E. pulchripes, whereas in A. gigas it is of salivary gland origin and acid activity restricted to the midgut. Some disaccharidases, with more alkaline activity, showed less apparent midgut-hindgut differences. It may indicate an axial separating of the primary and secondary digestion along the intestinal pH gradient or the presence of enzymes of hindgut parasites.
- MeSH
- celulasa metabolismus MeSH
- chitinasy metabolismus fyziologie MeSH
- členovci klasifikace enzymologie MeSH
- gastrointestinální trakt enzymologie MeSH
- koncentrace vodíkových iontů MeSH
- polysacharidy metabolismus MeSH
- proteasy metabolismus MeSH
- substrátová specifita MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
