Duodenal biopsies are considered a suitable source of enterocytes for studies of dietary iron absorption. However, the expression level of molecules involved in iron absorption may vary along the length of duodenum. We aimed to determine whether the expression of molecules involved in the absorption of heme and non-heme iron differs depending on the location in the duodenum. Analysis was performed with samples of duodenal biopsies from 10 individuals with normal iron metabolism. Samples were collected at the following locations: (a) immediately post-bulbar, (b) 1-2 cm below the papilla of Vater and (c) in the distal duodenum. The gene expression was analyzed at the mRNA and protein level using real-time PCR and Western blot analysis. At the mRNA level, significantly different expression of HCP1, DMT1, ferroportin and Zip8 was found at individual positions of duodenum. Position-dependent expression of other molecules, especially of FLVCR1, HMOX1 and HMOX2 was also detected but with no statistical significances. At the protein level, we observed statistically significantly decreasing expression of transporters HCP1, FLVCR1, DMT1, ferroportin, Zip14 and Zip8 with advancing positions of duodenum. Our results are consistent with a gradient of diminishing iron absorption along the duodenum for both heme and non-heme iron.
- MeSH
- duodenum * metabolismus MeSH
- hem metabolismus MeSH
- iontový transport MeSH
- lidé MeSH
- messenger RNA genetika metabolismus MeSH
- železo * metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Matrix-Liposomes (MLs) are a very promising solid oral drug delivery system; however, data on their interaction with biological membranes are not available. Here, we describe the quality of MLs manufactured by dual centrifugation. MLs were prepared with a Z-average range of 139 to 160 nm and a PDI of 0.18 to 0.25. To investigate the effect of MLs on intestinal tissue (with and without mucolytic treatment), we then established an ex vivo rat intestine model. The integrity of the epithelial membranes of rat intestine was not affected by the incubation with MLs without or with pre-mucolytic treatment. Tissue samples were also analysed for changes in P-glycoprotein (P-gp) expression and function. The net secretion of the P-gp substrate Rh123 across the rat duodenum was increased in the presence of MLs. To summarize, MLs do not affect intestinal epithelial integrity, although they impact Rh123 secretion. In future, these novel MLs have to be further evaluated for proficient intestinal drug delivery.
- MeSH
- biologické přípravky chemie MeSH
- biologický transport fyziologie MeSH
- duodenum metabolismus MeSH
- intestinální absorpce fyziologie MeSH
- krysa rodu rattus MeSH
- liposomy chemie MeSH
- P-glykoprotein metabolismus MeSH
- střevní sliznice metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
In mammals, leptin and tumor-necrosis factor (TNF) are prominent interacting adipokines mediating appetite control and insulin sensitivity. While TNF pleiotropically functions in immune defense and cell survival, leptin is largely confined to signaling energy stores in adipocytes. Knowledge about the function of avian leptin and TNF is limited and they are absent or lowly expressed in adipose, respectively. Employing radiation-hybrid mapping and FISH-TSA, we mapped TNF and its syntenic genes to chicken chromosome 16 within the major histocompatibility complex (MHC) region. This mapping position suggests that avian TNF has a role in regulating immune response. To test its possible interaction with leptin within the immune system and beyond, we compared the transcription patterns of TNF, leptin and their cognate receptors obtained by meta-analysis of GenBank RNA-seq data. While expression of leptin and its receptor (LEPR) were detected in the brain and digestive tract, TNF and its receptor mRNAs were primarily found in viral-infected and LPS-treated leukocytes. We confirmed leptin expression in the duodenum by immunohistochemistry staining. Altogether, we suggest that whereas leptin and TNF interact as adipokines in mammals, in birds, they have distinct roles. Thus, the interaction between leptin and TNF may be unique to mammals.
- MeSH
- buněčné linie MeSH
- duodenum metabolismus MeSH
- kur domácí genetika metabolismus MeSH
- leptin genetika metabolismus MeSH
- leptinové receptory metabolismus MeSH
- mapování chromozomů * MeSH
- mapování pomocí radiačních hybridů MeSH
- messenger RNA genetika metabolismus MeSH
- metafáze genetika MeSH
- receptory TNF genetika metabolismus MeSH
- regulace genové exprese * MeSH
- savci genetika MeSH
- signální transdukce * MeSH
- syntenie genetika MeSH
- TNF-alfa genetika metabolismus MeSH
- trávení * MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Patients with alcoholic liver disease (ALD) often display disturbed iron indices. Hepcidin, a key regulator of iron metabolism, has been shown to be down-regulated by alcohol in cell lines and animal models. This down-regulation led to increased duodenal iron transport and absorption in animals. In this study, we investigated gene expression of duodenal iron transport molecules and hepcidin in three groups of patients with ALD (with anaemia, with iron overload and without iron overload) and controls. Expression of DMT1, FPN1, DCYTB, HEPH, HFE and TFR1 was measured in duodenal biopsies by using real-time PCR and Western blot. Serum hepcidin levels were measured by using ELISA. Serum hepcidin was decreased in patients with ALD. At the mRNA level, expressions of DMT1, FPN1 and TFR1 genes were significantly increased in ALD. This pattern was even more pronounced in the subgroups of patients without iron overload and with anaemia. Protein expression of FPN1 paralleled the increase at the mRNA level in the group of patients with ALD. Serum ferritin was negatively correlated with DMT1 mRNA. The down-regulation of hepcidin expression leading to up-regulation of iron transporters expression in the duodenum seems to explain iron metabolism disturbances in ALD. Alcohol consumption very probably causes suppression of hepcidin expression in patients with ALD.
- MeSH
- alkoholické nemoci jater metabolismus MeSH
- cytochromy typu b genetika metabolismus MeSH
- dospělí MeSH
- duodenum metabolismus MeSH
- exprese genu MeSH
- hepcidiny fyziologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- membránové proteiny genetika metabolismus MeSH
- oxidoreduktasy genetika metabolismus MeSH
- proteiny přenášející kationty genetika metabolismus MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- studie případů a kontrol MeSH
- železo krev MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Exokrinní pankreatická nedostatečnost se vyvíjí plynule, avšak iniciální snížení sekrece není prakticky diagnostikovatelné, pokročilejší stadia, většinou kopírující změny morfologické, lze stanovit testy, posuzujícími exokrinní pankreatickou kapacitu. Při významné devastaci pankreatu a náhradě funkčního parenchymu vazivem je přítomna steatorea a tento nález odpovídá snížení exokrinní pankreatické sekrece pod 10 % fyziologické sekrece. Testy exokrinní pankreatické sekrece nejsou stále dostatečně citlivé pro diagnostiku časných stadií postižení pankreatu, a proto se k diagnostice nehodí, navíc nález snížené exokrinní sekrece nic neříká o etiologii onemocnění, např. zánět/nádor. Nejpřesnějším testem je ekonomicky nákladný test se stimulací žlázy enterohormony, ale pro posuzování efektu terapie exokrinní nedostatečnosti jsou doporučovány testy dechové. Terapie exokrinní pankreatické nedostatečnosti spočívá v podávání léků s obsahem pankreatinu (amyláza, lipáza, peptidáza), a to nejen u osob se steatoreou anebo manifestní pankreatickou nedostatečností. Jako standard jsou doporučeny preparáty ve formě kapslí, které obsahují mikročástice 1,0–2,0 mm velké, s ochranným obalem proti inaktivaci v mikročásticích obsažených enzymů žaludeční kyselinou chlorovodíkovou. Lék má být podáván při každém jídle, tj. několikrát denně. Nejčastější chybou v léčbě pankreatickými enzymy je jejich poddávkování. Platí, že při trávicí nedostatečnosti, při tzv. hlavních jídlech, má být podáno 40 000–50 000 j lipázy, při dopoledních anebo odpoledních svačinách 25 000 j lipázy. Nejlépe je podat lék během jídla. Nedostatečná léčba a dávkování je spojena s nedostatečným trávením a vstřebáváním řady látek a s obrazem pankreatické malabsorpce.
Exocrine pancreatic insufficiency develops steadily; however, the initial reduction in secretion is practically not diagnosable. More advanced stages, which usually replicate morphological changes, can be determined with tests which asses the exocrine pancreatic capacity. Substantial damage of the pancreas and replacement of viable parenchyma with connective tissue is accompanied by the occurrence of steatorrhoea. This corresponds to a reduction in exocrine pancreatic secretion below 10% of physiological secretion. Exocrine pancreatic secretion tests are still not sufficiently sensitive for diagnosing early stages of pancreas defects and thus are not suitable for diagnostics. Furthermore, detecting reduced exocrine secretion does not provide any information about the aetiology of the disease, e.g. inflammation/tumor. The most precise test is a costly examination, including a stimulation of the gland with enterohormones; however, breath tests are usually recommended for the assessment of exocrine insufficiency therapy. Exocrine pancreatic insufficiency therapy consists of administering drugs containing pancreatin (amylase, lipase, and peptidase) to patients diagnosed with steatorrhoea, manifest pancreatic insufficiency. As standard, capsules containing microparticles of 1–2mm are recommended. They have a protective coating that prevents inactivation in the microparticles of the contained enzymes by gastric hydrochloric acid. The drug should be administered during each meal, i.e. several times a day. The most common mistake during pancreatic enzyme therapy is underdosage. The following rule applies to patients with digestive insufficiency: 40,000–50,000 UNT of lipase are to be administered during “main meals” and 25,000 UNT of lipase during morning or afternoon snacks. The drug should be taken during the meal; insufficient treatment and dosage are associated with insufficient digestion and absorption of a number of substances and also with pancreatic malabsorption.
- Klíčová slova
- pankreatická sekrece, testy pankreatické sekrece, pankreatické enzymy,
- MeSH
- cholecystokinin analýza sekrece MeSH
- duodenum enzymologie metabolismus MeSH
- enzymová substituční terapie metody MeSH
- exokrinní pankreatická insuficience * diagnóza farmakoterapie patofyziologie MeSH
- funkční testy pankreatu * metody MeSH
- lidé MeSH
- lipasa aplikace a dávkování metabolismus terapeutické užití MeSH
- pankreas enzymologie patofyziologie sekrece MeSH
- pankreatin analýza sekrece MeSH
- sekretin analýza sekrece MeSH
- steatorea etiologie metabolismus MeSH
- střevní sekrety enzymologie účinky léků MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
Disturbances of iron metabolism are observed in chronic liver diseases. In the present study, we examined gene expression of duodenal iron transport molecules and hepcidin in patients with hereditary hemochromatosis (HHC) (treated and untreated), involving various genotypes (genotypes which represent risk for HHC were examined), and in patients with iron deficiency anaemia (IDA). Gene expressions of DMT1, ferroportin, Dcytb, hephaestin, HFE and TFR1 were measured in duodenal biopsies using real-time PCR and Western blot. Serum hepcidin levels were measured using ELISA. DMT1, ferroportin and TFR1 mRNA levels were significantly increased in post-phlebotomized hemochromatics relative to controls. mRNAs of all tested molecules were significantly increased in patients with IDA compared to controls. The protein expression of ferroportin was increased in both groups of patients but not significantly. Spearman rank correlations showed that DMT1 versus ferroportin, Dcytb versus hephaestin and DMT1 versus TFR1 mRNAs were positively correlated regardless of the underlying cause, similarly to protein levels of ferroportin versus Dcytb and ferroportin versus hephaestin. Serum ferritin was negatively correlated with DMT1 mRNA in investigated groups of patients, except for HHC group. A decrease of serum hepcidin was observed in IDA patients, but this was not statistically significant. Our data showed that although untreated HHC patients do not have increased mRNA levels of iron transport molecules when compared to normal subjects, the expression is relatively increased in relation to body iron stores. On the other hand, post-phlebotomized HHC patients had increased DMT1 and ferroportin mRNA levels possibly due to stimulated erythropoiesis after phlebotomy.
- MeSH
- biologický transport MeSH
- deficit železa MeSH
- dospělí MeSH
- duodenum metabolismus MeSH
- fenotyp MeSH
- hemochromatóza krev genetika metabolismus MeSH
- kationické antimikrobiální peptidy krev metabolismus MeSH
- lidé středního věku MeSH
- lidé MeSH
- messenger RNA genetika metabolismus MeSH
- proteiny přenášející kationty genetika metabolismus MeSH
- regulace genové exprese MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- studie případů a kontrol MeSH
- železo metabolismus MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND/AIMS: Measurement of the permeability of gut mucosa may offer a method for objective assessment of mucosal dysfunction during cancer therapy. METHODOLOGY: Gastroduodenal, intestinal and colonic permeability was studied by using capillary gas chromatography and measuring urinary sucralose, sucrose, lactulose, xylose and mannitol levels. A total of 41 patients with metastatic colorectal carcinoma or epithelial ovarian carcinoma were studied before and during chemotherapy with the combinations of cetuximab, irinotecan, 5-fluorouracil and leucovorin; bevacizumab, oxaliplatin, 5-fluorouracil and leucovorin; or paclitaxel/ platinum. RESULTS: Compared to pretreatment values, a significant increase was observed during the first cycle of therapy in the percentage of sucrose, sucrose/mannitol ratio, lactulose and lactulose/ mannitol ratio in patients treated with the combination of bevacizumab, oxaliplatin, 5-fluorouracil and leucovorin. No changes were observed in patients treated with cetuximab, irinotecan, 5-fluorouracil and leucovorin, but these patients had significantly higher baseline percentage of lactulose excretion and sucrose/mannitol and lactulose/ mannitol ratios. CONCLUSIONS: An increase in gastroduodenal and intestinal permeability was observed in patients treated with bevacizumab, oxaliplatin, 5-fluorouracil and leucovorin, but not in patients treated with cetuximab, irinotecan, 5-fluorouracil and leucovorin. No significant increase in colonic permeability was observed, but the present method was insufficient to detect colonic permeability in a significant proportion of patients.
- MeSH
- dospělí MeSH
- duodenum metabolismus MeSH
- kolon metabolismus MeSH
- lidé středního věku MeSH
- lidé MeSH
- permeabilita MeSH
- protinádorové látky farmakokinetika MeSH
- sacharosa analogy a deriváty farmakokinetika MeSH
- senioři MeSH
- střevní sliznice metabolismus MeSH
- žaludeční sliznice metabolismus MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
In last few years, numerous groups of proteins participating in the regulation of cell proliferation, differentiation and death during ontogenesis have been described. In this study we compared the occurrence of Bcl-2, p53 and myc protein families with the level of proliferative activity and apoptosis during development of duodenal epithelium. Paraffin embedded tissues of eight human embryos and foetuses aged from the 6th-18th week of IUD were used. For the detection of apoptotic cells the TUNEL method was performed, the proliferative marker PCNA and all the proteins studied were detected by means of indirect three-step immunohistochemical method. In the 6th and 8th week of intrauterine development we observed isolated TUNEL positive epithelial cells only and this was accompanied by the disperse presence of PCNA as well as by all the studied proteins: Bcl-2, Bax, Bcl-XL, c-myc, N-myc, p53, p63 and p73. In the early foetal period of duodenal development we registered changes in PCNA and TUNEL positivity in accordance with the constitution of the stem cell pool on base of villi, where more numerous Bcl-2 positive cells were also found. The separation of primitive crypts and villi was not accompanied by any differences in distribution of Bax, Bcl-XL, c-myc, N-myc, p63 and p73 proteins between those compartments: all the studied proteins showed dispersed character. P53 rapidly decreased in this period. In the 18th week of intrauterine development the balance between proliferation in crypts and apoptosis of villi epithelium was well established and no p53 positive cells were found. In the presence of Bcl-2, Bax, Bcl-XL, p63 and p73 we did not find any dramatic changes. The myc proteins were restricted within the epithelium of the Lieberkuhn crypts only.
- MeSH
- apoptóza MeSH
- duodenum cytologie embryologie metabolismus MeSH
- embryo savčí metabolismus MeSH
- epitel embryologie metabolismus MeSH
- imunohistochemie MeSH
- lidé MeSH
- nádorový supresorový protein p53 analýza MeSH
- proliferace buněk MeSH
- protoonkogenní proteiny c-bcl-2 analýza MeSH
- protoonkogenní proteiny c-myc analýza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- MeSH
- duodenum metabolismus účinky léků MeSH
- fluorescenční mikroskopie MeSH
- křečci praví MeSH
- pankreas metabolismus účinky léků MeSH
- radiosenzibilizující látky farmakokinetika farmakologie MeSH
- tkáňová distribuce MeSH
- žaludek metabolismus účinky léků MeSH
- žlučové cesty metabolismus účinky léků MeSH
- zvířata MeSH
- Check Tag
- křečci praví MeSH
- zvířata MeSH
