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1.
Clin Gastroenterol Hepatol ; 22(4): 810-820.e7, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37806372

RESUMO

BACKGROUND & AIMS: The aim of this study was to evaluate the efficacy of LT-02, a novel modified-release phosphatidylcholine (PC) formulation, for induction and maintenance of remission in patients with mild to moderate ulcerative colitis (UC) and inadequate response to mesalamine. METHODS: LT-02 was evaluated in a multicenter double-blind, randomized, placebo-controlled study comprising a 12-week induction trial (PCG-2), followed by a 48-week maintenance trial (PCG-4). In PCG-2, patients were randomized 1:1:1 to treatment with 0.8 g LT-02 4 times daily (QID), 1.6 g LT-02 twice daily (BID), or placebo, respectively. All patients continued to take a standard dose of oral mesalamine (≥2.4 g/day). The primary end point in PCG-2 was deep remission. Patients achieving remission at week 12 were randomly assigned 2:1:1 to 1.6 g LT-02 BID, placebo, or 500 mg mesalamine (3 times daily), respectively, in PCG-4; the primary end point was remission at 48 weeks. RESULTS: PCG-2 was terminated early for futility after a prespecified interim analysis; 466 patients (of 762 planned) were randomized. There was no statistically significant difference in deep remission at week 12 (placebo, 13.5%; LT-02 BID, 14.2%; LT-02 QID, 9.7%). In PCG-4, 150 patients (of approximately 400 planned) were randomized. There was no statistically significant difference in remission rates at week 48 (LT-02 BID, 49.3%; mesalamine, 50.0%; placebo, 43.2%). LT-02 was safe. CONCLUSIONS: Despite prior evidence of beneficial effects of PC in phase 2 trials, our induction study with LT-02 in patients with mild to moderate UC was terminated prematurely for futility. Signals of efficacy in maintenance therapy require confirmation in an adequately powered maintenance trial. LT-02 was safe and well-tolerated. CLINICALTRIALS: gov: NCT02280629, NCT02142725.


Assuntos
Colite Ulcerativa , Humanos , Colite Ulcerativa/tratamento farmacológico , Mesalamina/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Fosfatidilcolinas/uso terapêutico , Indução de Remissão , Método Duplo-Cego , Resultado do Tratamento
2.
Biomedicines ; 11(2)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36830958

RESUMO

Wilson disease (WD) is a rare, inherited metabolic disorder manifested with varying clinical presentations including hepatic, neurological, psychiatric, and ophthalmological features, often in combination. Causative mutations in the ATP7B gene result in copper accumulation in hepatocytes and/or neurons, but clinical diagnosis remains challenging. Diagnosis is complicated by mild, non-specific presentations, mutations exerting no clear effect on protein function, and inconclusive laboratory tests, particularly regarding serum ceruloplasmin levels. As early diagnosis and effective treatment are crucial to prevent progressive damage, we report here on the establishment of a global collaboration of researchers, clinicians, and patient advocacy groups to identify and address the outstanding challenges posed by WD.

3.
MMW Fortschr Med ; 164(Suppl 7): 3-11, 2022 07.
Artigo em Alemão | MEDLINE | ID: mdl-35831742

RESUMO

BACKGROUND: Phosphatidylcholine is an essential component of the intestinal mucus and serves as a protective shield against the ingress of bacteria from the stool. In the intestinal mucus of patients with ulcerative colitis, phosphatidylcholine is reduced by 70%, which makes the intestine susceptible to bacterial inflammation. Local application by administering enteric phosphatidylcholine could compensate for this deficiency. METHOD: A summary analysis of three clinical studies published until now with 160 included patients with ulcerative colitis was performed. RESULTS AND CONCLUSION: The meta-analysis showed that lecithin enriched with phosphatidylcholine and microencapsulated with Eudragit S-100 significantly improved the remission rate as well as the clinical and endoscopic picture. There was also an improvement in histology and quality of life. All parameters were significantly superior to placebo. The remission achieved was maintained significantly longer with enteric lecithin than with placebo. The side effect profile was identical to the placebo group, which is particularly important for the patients. In complementary medicine, phosphatidylcholine can be seen as protection for the intestines.


Assuntos
Colite Ulcerativa , Colite Ulcerativa/tratamento farmacológico , Humanos , Lecitinas/uso terapêutico , Qualidade de Vida , Indução de Remissão
4.
Biosci Rep ; 42(6)2022 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-35583196

RESUMO

Fatty acid (FA) metabolism is a series of processes that provide structural substances, signalling molecules and energy. Ample evidence has shown that FA uptake is mediated by plasma membrane transporters including FA transport proteins (FATPs), caveolin-1, fatty-acid translocase (FAT)/CD36, and fatty-acid binding proteins. Unlike other FA transporters, the functions of FATPs have been controversial because they contain both motifs of FA transport and fatty acyl-CoA synthetase (ACS). The widely distributed FATP4 is not a direct FA transporter but plays a predominant function as an ACS. FATP4 deficiency causes ichthyosis premature syndrome in mice and humans associated with suppression of polar lipids but an increase in neutral lipids including triglycerides (TGs). Such a shift has been extensively characterized in enterocyte-, hepatocyte-, and adipocyte-specific Fatp4-deficient mice. The mutants under obese and non-obese fatty livers induced by different diets persistently show an increase in blood non-esterified free fatty acids and glycerol indicating the lipolysis of TGs. This review also focuses on FATP4 role on regulatory networks and factors that modulate FATP4 expression in metabolic tissues including intestine, liver, muscle, and adipose tissues. Metabolic disorders especially regarding blood lipids by FATP4 deficiency in different cell types are herein discussed. Our results may be applicable to not only patients with FATP4 mutations but also represent a model of dysregulated lipid homeostasis, thus providing mechanistic insights into obesity and development of fatty liver disease.


Assuntos
Ácidos Graxos , Hepatopatias , Animais , Antígenos CD36/metabolismo , Proteínas de Transporte de Ácido Graxo/genética , Proteínas de Transporte de Ácido Graxo/metabolismo , Proteínas de Ligação a Ácido Graxo/metabolismo , Ácidos Graxos/metabolismo , Humanos , Lipídeos , Proteínas de Membrana Transportadoras , Camundongos , Obesidade/genética , Triglicerídeos
6.
Dig Dis ; 40(2): 232-238, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33839722

RESUMO

BACKGROUND: The pathophysiology of hepatic encephalopathy (HE) is incompletely understood. It remains elusive how the contributing factors of neuronal ammonia accumulation, cell swelling, and inflammation interact. OBJECTIVE: The objective of this study was to find the correlation between neuronal autoantibody levels and the degree of HE as first indication of immune-mediated pathogenesis. METHODS: We investigated serum autoantibody levels of representative brain proteins in patients with HE as well as in an experimental rat model with cirrhosis and HE after carbon tetrachloride exposure. They were examined in relation to presence of HE and the degree of neurological impairment evaluated by quantitative scores. RESULTS: In HE, an increase in all of the examined antibodies was observed in serum. The grade of antibody elevation correlated to the degree of encephalopathy registered by quantitative evaluation of brain dysfunction. CONCLUSION: The degree of HE parallels neuronal autoantibody elevation. In case a causal relationship could finally be established, it adds to the understanding of HE and may open a new perspective for treatment of this handicapping condition by immunosuppressive strategies.


Assuntos
Encefalopatia Hepática , Amônia , Animais , Autoanticorpos , Encefalopatia Hepática/etiologia , Humanos , Cirrose Hepática/complicações , Ratos , Fatores de Virulência
7.
Biomedicines ; 9(12)2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34944677

RESUMO

Bis-choline-tetrathiomolybdate, introduced as WTX101 (now known as ALXN1840), is a first-in-class copper-protein-binding agent for oral therapy of Wilson's disease. In contrast to other decoppering agents such as trientine or D-penicillamine it acts by forming a tripartite complex with copper and albumin, thereby detoxifying excess liver and blood copper through biliary excretion. Preclinical animal experimentation with this drug was typically done with the alternative ammonium salt of tetrathiomolybdate, which is expected to have identical properties in terms of copper binding. Here, we comparatively analyzed the therapeutic efficacy of ALXN1840, D-penicillamine and trientine in lowering hepatic copper content in Atp7b-/- mouse. Liver specimens were subjected to laser ablation inductively conductively plasma mass spectrometry and electron microscopic analysis. We found that ALXN1840 caused a massive increase of hepatic copper and molybdenum during early stages of therapy. Prolonged treatment with ALXN1840 reduced hepatic copper to an extent that was similar to that observed after administration of D-penicillamine and trientine. Electron microscopic analysis showed a significant increase of lysosomal electron-dense particles in the liver confirming the proposed excretory pathway of ALXN1840. Ultrastructural analysis of mice treated with dosages comparable to the bis-choline-tetrathiomolybdate dosage used in an ongoing phase III trial in Wilson's disease patients, as well as D-penicillamine and trientine, did not show relevant mitochondrial damage. In contrast, a high dose of ALXN1840 applied for four weeks triggered dramatic structural changes in mitochondria, which were notably characterized by the formation of holes with variable sizes. Although these experimental results may not be applicable to patients with Wilson's disease, the data suggests that ALXN1840 should be administered at low concentrations to prevent mitochondrial dysfunction and overload of hepatic excretory pathways.

8.
Environ Monit Assess ; 193(12): 778, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34748093

RESUMO

Spread of the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) is a demanding challenge. This is of particular importance in schools and public areas of unavoidable access. New viral mutations may increase infectivity and require even better methods to identify areas of potential hazards. High-throughput SARS-CoV-2 testing and legal restrictions are not effective in order to get the current outbreak under control. The occurrence of new SARS-CoV-2 variants with a higher transmissibility requires efficient strategies for early detection and surveillance. Until today, testing focuses on nasal or pharyngeal mucosa swabs, neglecting the origin of aerosolic transmission, thus failing to detect the spread by carriers of the virus. Therefore, in this study, SARS-CoV-2 RNA levels were determined by quantitative real time PCR in aerosols collected by non-powered cold traps. SARS-CoV-2 spreading kinetics were recorded in indoor hotspots within a high-endemic area. These hotspots included a SARS-CoV-2 isolation unit, an outpatient endoscopy facility, a concert hall, and a shopping mall. For determination of viral presence aerosols were collected by cold traps positioned at different locations in the area of interest over a period of 4-6 h. Indoor SARS-CoV-2 hotspots were found in non-ventilated areas and in zones that are predisposed to a buoyancy (chimney) effect. SARS-CoV-2 RNA in those aerosols reached concentrations of 105 copies/mL, while extensive outdoor air ventilation reliably eliminated SARS-CoV-2 aerosol contamination. The method presented herein is effective for the identification of SARS-CoV-2 indoor hotspots and may help to characterize the spreading kinetics of SARS-CoV-2. Moreover, it can be used for the surveillance of emerging SARS-CoV-2 variants. Due to low costs and easy handling, the procedure might enable efficient algorithms for COVID-19 screening and prevention.


Assuntos
COVID-19 , SARS-CoV-2 , Aerossóis , Teste para COVID-19 , Monitoramento Ambiental , Humanos , RNA Viral
10.
Biomolecules ; 11(6)2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200323

RESUMO

Multiple biologically active components of human milk support infant growth, health and development. Milk provides a wide spectrum of mammary epithelial cell-derived extracellular vesicles (MEVs) for the infant. Although the whole spectrum of MEVs appears to be of functional importance for the growing infant, the majority of recent studies report on the MEV subfraction of milk exosomes (MEX) and their miRNA cargo, which are in the focus of this review. MEX and the dominant miRNA-148a play a key role in intestinal maturation, barrier function and suppression of nuclear factor-κB (NF-κB) signaling and may thus be helpful for the prevention and treatment of necrotizing enterocolitis. MEX and their miRNAs reach the systemic circulation and may impact epigenetic programming of various organs including the liver, thymus, brain, pancreatic islets, beige, brown and white adipose tissue as well as bones. Translational evidence indicates that MEX and their miRNAs control the expression of global cellular regulators such as DNA methyltransferase 1-which is important for the up-regulation of developmental genes including insulin, insulin-like growth factor-1, α-synuclein and forkhead box P3-and receptor-interacting protein 140, which is important for the regulation of multiple nuclear receptors. MEX-derived miRNA-148a and miRNA-30b may stimulate the expression of uncoupling protein 1, the key inducer of thermogenesis converting white into beige/brown adipose tissue. MEX have to be considered as signalosomes derived from the maternal lactation genome emitted to promote growth, maturation, immunological and metabolic programming of the offspring. Deeper insights into milk's molecular biology allow the conclusion that infants are both "breast-fed" and "breast-programmed". In this regard, MEX miRNA-deficient artificial formula is not an adequate substitute for breastfeeding, the birthright of all mammals.


Assuntos
Desenvolvimento Infantil/fisiologia , Exossomos/metabolismo , Microbioma Gastrointestinal/fisiologia , Saúde do Lactente , MicroRNAs/metabolismo , Leite Humano/metabolismo , Exossomos/genética , Humanos , Lactente , Recém-Nascido , Mucosa Intestinal/metabolismo , MicroRNAs/genética
11.
Ann Transl Med ; 9(8): 725, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33987423
12.
Ann Transl Med ; 9(8): 732, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33987430

RESUMO

Wilson disease is a copper overload disease treatable with the chelators D-penicillamine and trientine to enhance urinary excretion or with zinc which predominantly inhibits absorption. By lifelong treatment a normal life expectancy and significant improvement of hepatic injury as well as neurologic manifestation is achievable. Here we evaluate the mode of action for effective therapy of Wilson disease. We postulate that there is no quantitative removal of copper from the liver possible. The therapeutic goal is the removal of toxic free copper (non-ceruloplasmin, but albumin bound copper). This is achievable by the induction of metallothionein which is accomplished by chelators and in particular by zinc. For control of therapy the option of a direct measurement of free copper would be preferable over the less reliable calculation of this fraction. A therapeutic challenge is still the full restoration of neurological deficits which can hardly be reached by the available chelators. Whether bis-choline-tetrathiomolybdate as intracellular copper chelator is an option has to be awaited. It is concluded that the goal of actual drug therapy in Wilson disease is the normalization of free copper in serum.

13.
Ann Transl Med ; 9(8): 738, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33987436

RESUMO

Primary sclerosing cholangitis (PSC) is a rare progressive cholangitis resulting in cirrhosis and cholangiocellular carcinoma. The pathogenesis is unclear and an effective medical therapy is not available. It is highly associated to ulcerative colitis for which recently a disturbance of the tight junction (TJ) barrier has been claimed as etiologic feature. Genetic mouse models with intestinal TJ disruption showed a defective transport of phosphatidylcholine (PC) to intestinal mucus. Consequently, an ulcerative colitis phenotype developed. In the present study we evaluate whether there is also a paracellular transport of PC through TJ to the apical side of cholangiocytes. As in ulcerative colitis, a TJ defect could lead to deficient PC in biliary mucus. It would impair the protective barrier against aggressive bile acids in bile. Indeed with polarized biliary tumor cells a vectorial transport of PC from basal to luminal side was demonstrated using a transwell culture system. PC was not taken up by the cells but moved paracellularly via TJ to the apical side driven by luminal HCO3- generated by the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) and the anion exchange protein 2 (AE2). If such a TJ-mediated PC translocation to the apical surface of cholangiocytes could be disrupted in a genetic mouse model, a PSC phenotype would be expected. With such an experimental model functional operative therapies can be evaluated. We propose that disruption of TJ mediated paracellular transport of PC to the apical side of cholangiocytes could lead to biliary mucus PC depletion. This may be a pathogenetic factor for development of PSC.

14.
World J Clin Cases ; 9(6): 1386-1393, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33644206

RESUMO

BACKGROUND: In Wilson disease lack of biliary copper excretion causes hepatocellular injury by accumulation of free toxic copper. Its overspill to serum accounts for neuronal damage as second common manifestation. Therapy with copper chelators or zinc targets the removal of this free copper. However, in some patients liver disease persists for unknown reason despite normalized free copper. The discovery of a hyperimmunity as a contributing pathogenetic factor was discovered in this case report with implication also for other liver diseases. CASE SUMMARY: A 9-year-old girl was diagnosed in August 2009 by family screening of having asymptomatic Wilson disease with elevated transaminases. Already at time of diagnosis antinuclear antibodies (ANA) were elevated without hyperimmunoglobulinemia (immunoglobulin G, IgG). After one year of therapy with D-penicillamine transaminases normalized together with free serum copper. Under continuous therapy with copper chelators free copper remained normal until today, whereas transaminases raised to alanine aminotransferase values of 571 U/L in December 2019. For hyperimmunity a tentative steroid course on top of D-penicillamine improved transaminases. Thus, hyperimmunity may have impact on liver inflammation after control of the metabolic disturbance. A retrospective cohort study confirmed the common association of elevated transaminases with ANA, but no IgG elevation. CONCLUSION: This hyperimmune-triggered condition may represent a new entity which per se or on top of other liver diseases induces liver inflammation responsive to steroids.

15.
Dig Dis ; 39(5): 508-515, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33440385

RESUMO

BACKGROUND: Phosphatidylcholine (PC) is intrinsically missing in intestinal mucus of patients with ulcerative colitis. Topical supplementation with delayed intestinal release PC formulations is assumed to compensate this lack. Three monocenter randomized controlled trials (RCTs) with a 30% PC-containing lecithin were successful, whereas 1 trial with >94% PC-containing lecithin failed. OBJECTIVES: Evaluation of 30% PC-containing lecithin provided in a delayed intestinal release formulation for treatment efficacy of ulcerative colitis was evaluated by meta-analysis of 3 RCTs. METHODS: Meta-analysis of 3 studies was performed using RevMan 5.3 software. Odds ratio (OR) and 95% Cl were calculated for remission, clinical and endoscopic improvement, histology, and life quality. p values <0.05 were accepted as significant. RESULTS: The meta-analysis of 3 RTCs with 160 included patients with ulcerative colitis verified that PC improved the rate of remission (OR = 9.68), as well as clinical (OR = 30.58) and endoscopic outcomes (OR = 36.73). Within the available patient population, also histology and quality of life became better. All effects were significant over placebo. Achieved remission was maintained in a higher percentage of patients under intestinal-release PC formulation than placebo. The profile of adverse events was identical to the placebo population. CONCLUSIONS: A 30% PC-containing lecithin in delayed intestinal release formulation improves clinical and endoscopic outcomes, histologic activity, and quality of life in patients with ulcerative colitis. For the patients, lack of adverse events is an important consideration.


Assuntos
Colite Ulcerativa , Administração Oral , Colite Ulcerativa/tratamento farmacológico , Humanos , Quimioterapia de Indução , Lecitinas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Indução de Remissão , Resultado do Tratamento
16.
Inflamm Intest Dis ; 5(3): 117-123, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32999884

RESUMO

BACKGROUND: Milk is rich in nutrients and anabolic mediators rendering it essential for postnatal growth and metabolic programming. However, in adults, excessive consumption of milk is controversial as civilization disorders such as diabetes or prostate cancer may be promoted. A cytoprotective effect of milk could be utilized in inflammatory conditions, that is, chronic colitis. OBJECTIVE: To evaluate the effect of bovine milk exosomes on intestinal inflammation in a genetic mouse model of ulcerative colitis. METHODS: Intestinal-specific kindlin 2 knockout (KO) mice were exposed for 4 days to tamoxifen for induction of an ulcerative colitis phenotype. At the same time 4 other kindlin 2 KO mice were exposed to 33 µg/g cow milk derived exosomes in PBS by oral gavage. Both groups were compared to untreated wild-type controls. RESULTS: Milk exosomes prevented the appearance of a severe ulcerative phenotype. The macroscopic colitis score dropped from a mean of 3.33 in untreated mice to 0.75 index points (p < 0.01) in exosome-treated mice, which included significant improvement of the subscores of stool improvement and colon weight and length. Treated mice featured a noninflamed appearance of the intestinal mucosa. KEY MESSAGE: Milk exosomes have cytoprotective/anti-inflammatory activity in a genetic mouse model of ulcerative colitis. The mechanisms behind this need to be elucidated. This pilot study needs verification before a therapeutic strategy is developed.

17.
Mol Nutr Food Res ; 64(22): e2000361, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32991778

RESUMO

SCOPE: Inadequate intake of choline commonly leads to liver diseases. Methionine- and choline-deficient diets (MCDD) induce fatty liver in mice which is partly mediated by triglyceride (TG) lipolysis in white adipose tissues (WATs). Because Fatp4 knockdown has been shown to increase adipocyte lipolysis in vitro, here, the effects of MCDD on WAT lipolysis in aP2-Cre Fatp4-knockout (Fatp4A-/- ) mice are determined. METHODS AND RESULTS: Isolated WATs of Fatp4A-/- mice exposed to MCD medium show an increase in lipolysis, and the strongest effect is noted on glycerol release from subcutaneous fat. Fatp4A-/- mice fed with MCDD for 4 weeks show an increase in serum glycerol, TG, and leptin levels associated with the activation of hormone-sensitive lipase in subcutaneous fat. Chow-fed Fatp4A-/- mice also show an increase in serum leptin and very-low-density lipoproteins as well as liver phosphatidylcholine and sphingomyelin levels. Both chow- and MCDD-fed Fatp4A-/- mice show a decrease in serum ketone and WAT sphingomyelin levels which supports a metabolic shift to TG for subsequent WAT lipolysis CONCLUSIONS: Adipose Fatp4 deficiency leads to TG lipolysis and leptin release, which are exaggerated by MCDD. The data imply hyperlipidemia risk by a low dietary choline intake and gene mutations that increase adipose TG levels.


Assuntos
Tecido Adiposo/metabolismo , Colina/farmacologia , Leptina/metabolismo , Lipólise/fisiologia , Metionina/farmacologia , Tecido Adiposo/efeitos dos fármacos , Animais , Dieta , Proteínas de Transporte de Ácido Graxo/genética , Feminino , Glicerol/sangue , Cetonas/sangue , Leptina/sangue , Lipólise/efeitos dos fármacos , Fígado/patologia , Masculino , Metionina/deficiência , Camundongos Knockout , Camundongos Transgênicos , Triglicerídeos/sangue
18.
Biomedicines ; 8(9)2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32948070

RESUMO

Wilson disease is a rare inherited autosomal recessive disorder. As a consequence of genetic alterations in the ATP7B gene, copper begins to accumulate in the body, particularly in the liver and brain. Affected persons are prone to develop liver cancer and severe psychiatric and neurological symptoms. Clinically, the development of corneal Kayser-Fleischer rings and low ceruloplasmin concentrations (<20 mg/dL) are indicative of Wilson disease. However, the detection of elevated hepatic copper content (>250 µg/g dry weight) alone is still considered as the best but not exclusive diagnostic test for Wilson disease. Presently, specific copper stains (e.g., rhodanine) or indirect staining for copper-associated proteins (e.g., orcein) are widely used to histochemically visualize hepatic copper deposits. However, these procedures only detect lysosomal copper, while cytosolic copper is not detectable. Similarly, elemental analysis in scanning electron microscope with energy dispersive X-ray analysis (EDX) often leads to false negative results and inconsistencies. Here, we tested the diagnostic potential of laser ablation inductively-coupled mass spectrometry (LA-ICP-MS) that allows quantitative analysis of multiple elements. Comparative studies were performed in wild type and the Atp7b null mouse model. We propose LA-ICP-MS as a versatile and powerful method for the accurate determination of hepatic copper in people with Wilson disease with high spatial resolution.

19.
BMC Gastroenterol ; 20(1): 230, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32680469

RESUMO

BACKGROUND: Hereditary hemochromatosis (HH) is an autosomal recessive genetic disorder with increased intestinal iron absorption and therefore iron Overload. iron overload leads to increased levels of toxic non-transferrin bound iron which results in oxidative stress and lipid peroxidation. The impact of iron on lipid metabolism is so far not fully understood. The aim of this study was to investigate lipid metabolism including lipoproteins (HDL, LDL), neutral (triglycerides, cholesterol) and polar lipids (sphingo- and phospholipids), and PNPLA3 polymorphism (rs738409/I148M) in HH. METHODS: We conducted a cohort study of 54 subjects with HH and 20 healthy subjects. Patients were analyzed for their iron status including iron, ferritin, transferrin and transferrin saturation and serum lipid profile on a routine follow-up examination. RESULTS: HH group showed significantly lower serum phosphatidylcholine (PC) and significantly higher phosphatidylethanolamine (PE) compared to healthy control group. The ratio of PC/PE was clearly lower in HH group indicating a shift from PC to PE. Triglycerides were significantly higher in HH group. No differences were seen for HDL, LDL and cholesterol. Hepatic steatosis was significantly more frequent in HH. PNPLA3 polymorphism (CC vs. CG/GG) did not reveal any significant correlation with iron and lipid parameters including neutral and polar lipids, grade of steatosis and fibrosis. CONCLUSION: Our study strengthens the hypothesis of altered lipid metabolism in HH and susceptibility to nonalcoholic fatty liver disease. Disturbed phospholipid metabolism may represent an important factor in pathogenesis of hepatic steatosis in HH.


Assuntos
Hemocromatose , Sobrecarga de Ferro , Lipase , Proteínas de Membrana , Estudos de Coortes , Hemocromatose/complicações , Hemocromatose/genética , Humanos , Lipidômica , Fígado , Proteínas de Membrana/genética
20.
Int J Mol Sci ; 20(22)2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31717968

RESUMO

The bile acid-phospholipid conjugate ursodeoxycholyl-lysophosphatidylethanolamide (UDCA-LPE) was shown to have anti-inflammatory, antisteatotic, and antifibrotic properties, rendering it as a drug targeting non-alcoholic steatohepatitis (NASH). On a molecular level, it disrupted the heterotetrameric fatty acid uptake complex localized in detergent-resistant membrane domains of the plasma membrane (DRM-PM). However, its mode of action was unclear. Methodologically, UDCA-LPE was incubated with the liver tumor cell line HepG2 as well as their isolated DRM-PM and all other cellular membranes (non-DRM). The membrane cholesterol and phospholipids were quantified as well as the DRM-PM protein composition by Western blotting. The results show a loss of DRM-PM by UDCA-LPE (50 µM) with a 63.13 ± 7.14% reduction of phospholipids and an 81.94 ± 8.30% reduction of cholesterol in relation to mg total protein. The ratio of phospholipids to cholesterol changed from 2:1 to 4:1, resembling those of non-DRM fractions. Among the members of the fatty acid uptake complex, the calcium-independent membrane phospholipase A2 (iPLA2ß) abandoned DRM-PM most rapidly. As a consequence, the other members of this transport system disappeared as well as the DRM-PM anchored fibrosis regulating proteins integrin ß-1 and lysophospholipid receptor 1 (LPAR-1). It is concluded that UDCA-LPE executes its action by iPLA2ß removal from DRM-PM and consequent dissolution of the raft lipid platform.


Assuntos
Colesterol/metabolismo , Lisofosfolipídeos/farmacologia , Microdomínios da Membrana/efeitos dos fármacos , Fosfolipases A2/metabolismo , Ácido Ursodesoxicólico/análogos & derivados , Células Hep G2 , Humanos , Integrina beta1/metabolismo , Microdomínios da Membrana/metabolismo , Receptores de Ácidos Lisofosfatídicos/metabolismo , Ácido Ursodesoxicólico/farmacologia
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