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1.
J Biomed Opt ; 28(10): 107001, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37915398

RESUMO

Significance: Evaluation of biological chromophore levels is useful for detection of various skin diseases, including cancer, monitoring of health status and tissue metabolism, and assessment of clinical and physiological vascular functions. Clinically, it is useful to assess multiple different chromophores in vivo with a single technique or instrument. Aim: To investigate the possibility of estimating the concentration of four chromophores, bilirubin, oxygenated hemoglobin, deoxygenated hemoglobin, and melanin from diffuse reflectance spectra in the visible region. Approach: A new diffuse reflectance spectroscopic method based on the multiple regression analysis aided by Monte Carlo simulations for light transport was developed to quantify bilirubin, oxygenated hemoglobin, deoxygenated hemoglobin, and melanin. Three different experimental animal models were used to induce hyperbilirubinemia, hypoxemia, and melanogenesis in rats. Results: The estimated bilirubin concentration increased after ligation of the bile duct and reached around 18 mg/dl at 50 h after the onset of ligation, which corresponds to the reference value of bilirubin measured by a commercially available transcutaneous bilirubin meter. The concentration of oxygenated hemoglobin and that of deoxygenated hemoglobin decreased and increased, respectively, as the fraction of inspired oxygen decreased. Consequently, the tissue oxygen saturation dramatically decreased. The time course of melanin concentration after depilation of skin on the back of rats was indicative of the supply of melanosomes produced by melanocytes of hair follicles to the growing hair shaft. Conclusions: The results of our study showed that the proposed method is capable of the in vivo evaluation of percutaneous bilirubin level, skin hemodynamics, and melanogenesis in rats, and that it has potential as a tool for the diagnosis and management of hyperbilirubinemia, hypoxemia, and pigmented skin lesions.


Assuntos
Bilirrubina , Melaninas , Ratos , Animais , Melaninas/análise , Bilirrubina/análise , Bilirrubina/metabolismo , Análise Espectral/métodos , Pele/química , Hipóxia/diagnóstico por imagem , Hemoglobinas/análise , Oxiemoglobinas/análise , Hiperbilirrubinemia/diagnóstico por imagem , Hiperbilirrubinemia/metabolismo
2.
Environ Toxicol Pharmacol ; 104: 104321, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37984676

RESUMO

This study aimed to investigate the induction of mild unconjugated hyperbilirubinemia in hepatic UGT1A1 inhibition by Morpholinos antisense in CsA-treated BLC57 mice in comparison with the efficacy of chitosan (CH) as an anti-hypolipidemic natural product. Antisense morpholino oligonucleotides were injected intravenously into CsA-treated mice for 14 days thrice a week. Serum biochemical parameters, antioxidant status, and gene expression analysis of eNOS, PPAR-α, NF-kB, cFn, AT1-R, and ETA-R were determined in cardiac tissues with confirmation by histopathology. Inhibition of UGT1A1 significantly elevated serum unconjugated bilirubin within a physiological range. Furthermore, induced mild hyperbilirubinemia reduces hyperlipidemia, improves antioxidant status, and significantly increases the expression of the cardiac PPAR-α gene while decreasing, ETA-R, iNOS, NF-kB, cFn and AT1-R gene expression in CsA-treated mice. Importantly, mild unconjugated hyperbilirubinemia within physiological ranges may be used as a novel therapeutic strategy to lower hyperlipidemia, atherosclerosis, hypertension, and the CVD outcomes in CsA- treated transplant recipients.


Assuntos
Hiperlipidemias , Hipertensão , Camundongos , Animais , Morfolinos , Ciclosporina , NF-kappa B/genética , NF-kappa B/metabolismo , Oligonucleotídeos Antissenso/uso terapêutico , Bilirrubina , Antioxidantes , Receptores Ativados por Proliferador de Peroxissomo , Hiperbilirrubinemia/induzido quimicamente , Hiperbilirrubinemia/genética , Hiperbilirrubinemia/metabolismo , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/genética , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo
3.
Stem Cell Reports ; 18(11): 2071-2083, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37832542

RESUMO

UGT1A1 (UDP glucuronosyltransferase family 1 member A1) is the primary enzyme required for bilirubin conjugation, which is essential for preventing hyperbilirubinemia. Animal models lack key human organic anion transporting polypeptides with distinct epigenetic control over bilirubin metabolism, necessitating a human model to interrogate the regulatory mechanism behind UGT1A1 function. Here, we use induced pluripotent stem cells to develop human liver organoids that can emulate conjugation failure phenotype. Bilirubin conjugation assays, chromatin immunoprecipitation, and transcriptome analysis elucidated the role of glucocorticoid antagonism in UGT1A1 activation. This antagonism prevents the binding of transcriptional repressor MECP2 at the expense of NRF2 with associated off-target effects. Therefore, we introduced functional GULO (L-gulonolactone oxidase) in human organoids to augment intracellular ascorbate for NRF2 reactivation. This engineered organoid conjugated more bilirubin and protected against hyperbilirubinemia when transplanted in immunosuppressed Crigler-Najjar syndrome rat model. Collectively, we demonstrate that our organoid system serves as a manipulatable model for interrogating hyperbilirubinemia and potential therapeutic development.


Assuntos
Síndrome de Crigler-Najjar , Células-Tronco Pluripotentes , Humanos , Animais , Ratos , Bilirrubina/farmacologia , Bilirrubina/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fígado/metabolismo , Síndrome de Crigler-Najjar/genética , Síndrome de Crigler-Najjar/terapia , Hiperbilirrubinemia/genética , Hiperbilirrubinemia/metabolismo , Hiperbilirrubinemia/terapia , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Células-Tronco Pluripotentes/metabolismo
4.
J Hepatol ; 79(4): 1049-1055, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37390966

RESUMO

Gilbert's syndrome, also known as benign hyperbilirubinaemia, was described more than 100 years ago. It has usually been considered a physiological abnormality characterised by a mild elevation of the systemic level of unconjugated bilirubin, in the absence of any underlying liver or overt haemolytic disease. However, since the re-discovery of the potent antioxidant effects of bilirubin in the late 1980s, as well as multiple intracellular signalling pathways affected by bilirubin, an ever-increasing body of evidence suggests that individuals with Gilbert's syndrome may benefit from the mild hyperbilirubinaemia and are actually protected from the development of a wide variety of "diseases of civilisation" such as cardiovascular diseases, certain cancers, and autoimmune or neurodegenerative diseases. This review analyses the current state of medical knowledge given recent discoveries in this rapidly developing field, as well as their possible clinical significance, and provides a new perspective on this condition.


Assuntos
Doença de Gilbert , Humanos , Doença de Gilbert/metabolismo , Hiperbilirrubinemia/metabolismo , Fígado/metabolismo , Bilirrubina/metabolismo , Antioxidantes
5.
Br J Pharmacol ; 180(13): 1690-1709, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36692417

RESUMO

BACKGROUND AND PURPOSE: Liver failure is associated with psychiatric alterations, partly resulting from the increased brain dopamine levels. We investigated the relationship between increased dopamine levels and mental abnormalities using bile duct ligation (BDL) rats and the mechanism by which liver failure increased dopamine levels in SH-SY5Y cells. Behavioural tests were carried out on day 13 and 27 following BDL, along with measurements of dopamine and metabolites, expressions of enzymes and transporters related to dopamine metabolism, and its transport into the cortex and the hippocampus. SH-SY5Y cells were used to investigate whether NH4 Cl, bile acids and bilirubin affected expression of tyrosine hydroxylase or not. Tyrosine hydroxylase (TH) expression in SH-SY5Y cells co-incubated with bilirubin and signal pathway inhibitors was measured. KEY RESULTS: Open-field test results demonstrated BDL rats showed anxiety-like behaviour, accompanied by increased dopamine levels and expression of TH protein in the cortex. Membrane bound long form (MB)-COMT, slightly but significantly decreased. SH-SY5Y cells indicated that increased bilirubin levels was a factor in inducing TH expression. Both inhibitor of NF-κB pathway BAY 11-7082 and silencing NF-κB p65 reversed bilirubin-induced upregulation of TH protein. NF-κB activator TNF-α increased expression of TH protein. Roles of bilirubin in increases of TH protein expressions and dopamine levels were measured using hyperbilirubinemia rats. Anxiety-like behaviour, was associated with increased dopamine levels and TH protein expressions in hyperbilirubinemia rats. CONCLUSION AND IMPLICATIONS: BDL significantly increased dopamine levels in rat cortex partly due to bilirubin-mediated TH induction. Increased bilirubin induced TH expression via activating NF-κB signalling pathway.


Assuntos
Falência Hepática , Neuroblastoma , Ratos , Humanos , Animais , Tirosina 3-Mono-Oxigenase/metabolismo , Dopamina/metabolismo , NF-kappa B/metabolismo , Neuroblastoma/metabolismo , Ductos Biliares/cirurgia , Falência Hepática/metabolismo , Hiperbilirrubinemia/metabolismo , Bilirrubina/metabolismo , Bilirrubina/farmacologia , Ligadura , Córtex Cerebral/metabolismo , Fígado/metabolismo
6.
Gut ; 72(3): 549-559, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35444014

RESUMO

OBJECTIVE: Multidrug resistance protein 2 (MRP2) is a bottleneck in bilirubin excretion. Its loss is sufficient to induce hyperbilirubinaemia, a prevailing characteristic of acute liver failure (ALF) that is closely associated with clinical outcome. This study scrutinises the transcriptional regulation of MRP2 under different pathophysiological conditions. DESIGN: Hepatic MRP2, farnesoid X receptor (FXR) and Forkhead box A2 (FOXA2) expression and clinicopathologic associations were examined by immunohistochemistry in 14 patients with cirrhosis and 22 patients with ALF. MRP2 regulatory mechanisms were investigated in primary hepatocytes, Fxr -/- mice and lipopolysaccharide (LPS)-treated mice. RESULTS: Physiologically, homeostatic MRP2 transcription is mediated by the nuclear receptor FXR/retinoid X receptor complex. Fxr-/- mice lack apical MRP2 expression and rapidly progress into hyperbilirubinaemia. In patients with ALF, hepatic FXR expression is undetectable, however, patients without infection maintain apical MRP2 expression and do not suffer from hyperbilirubinaemia. These patients express FOXA2 in hepatocytes. FOXA2 upregulates MRP2 transcription through binding to its promoter. Physiologically, nuclear FOXA2 translocation is inhibited by insulin. In ALF, high levels of glucagon and tumour necrosis factor α induce FOXA2 expression and nuclear translocation in hepatocytes. Impressively, ALF patients with sepsis express low levels of FOXA2, lose MRP2 expression and develop severe hyperbilirubinaemia. In this case, LPS inhibits FXR expression, induces FOXA2 nuclear exclusion and thus abrogates the compensatory MRP2 upregulation. In both Fxr -/- and LPS-treated mice, ectopic FOXA2 expression restored apical MRP2 expression and normalised serum bilirubin levels. CONCLUSION: FOXA2 replaces FXR to maintain MRP2 expression in ALF without sepsis. Ectopic FOXA2 expression to maintain MRP2 represents a potential strategy to prevent hyperbilirubinaemia in septic ALF.


Assuntos
Fator 3-beta Nuclear de Hepatócito , Falência Hepática Aguda , Proteína 2 Associada à Farmacorresistência Múltipla , Animais , Camundongos , Bilirrubina , Fator 3-beta Nuclear de Hepatócito/metabolismo , Hepatócitos/metabolismo , Hiperbilirrubinemia/metabolismo , Hiperbilirrubinemia/patologia , Lipopolissacarídeos/metabolismo , Fígado/metabolismo , Falência Hepática Aguda/metabolismo , Proteína 2 Associada à Farmacorresistência Múltipla/metabolismo
7.
Fluids Barriers CNS ; 19(1): 47, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672829

RESUMO

BACKGROUND: Severe neonatal jaundice resulting from elevated levels of unconjugated bilirubin in the blood induces dramatic neurological impairment. Central oxidative stress and an inflammatory response have been associated with the pathophysiological mechanism. Cells forming the blood-brain barrier and the choroidal blood-CSF barrier are the first CNS cells exposed to increased plasma levels of unconjugated bilirubin. These barriers are key regulators of brain homeostasis and require active oxidative metabolism to fulfill their protective functions. The choroid plexus-CSF system is involved in neuroinflammatory processes. In this paper, we address the impact of neonatal hyperbilirubinemia on some aspects of brain barriers. We describe physiological changes in the neurovascular network, blood-brain/CSF barriers integrities, and CSF cytokine levels during the postnatal period in normobilirubinemic animals, and analyze these parameters in parallel in Gunn rats that are deficient in bilirubin catabolism and develop postnatal hyperbilirubinemia. METHODS: Gunn rats bearing a mutation in UGT1a genes were used. The neurovascular network was analyzed by immunofluorescence stereomicroscopy. The integrity of the barriers was evaluated by [14C]-sucrose permeability measurement. CSF cytokine levels were measured by multiplex immunoassay. The choroid plexus-CSF system response to an inflammatory challenge was assessed by enumerating CSF leukocytes. RESULTS: In normobilirubinemic animals, the neurovascular network expands postnatally and displays stage-specific regional variations in its complexity. Network expansion is not affected by hyperbilirubinemia. Permeability of the blood-brain and blood-CSF barriers to sucrose decreases between one- and 9-day-old animals, and does not differ between normobilirubinemic and hyperbilirubinemic rats. Cytokine profiles differ between CSF and plasma in all 1-, 9-, and 18-day-old animals. The CSF cytokine profile in 1-day-old animals is markedly different from that established in older animals. Hyperbilirubinemia perturbs these cytokine profiles only to a very limited extent, and reduces CSF immune cell infiltration triggered by systemic exposure to a bacterial lipopeptide. CONCLUSION: The data highlight developmental specificities of the blood-brain barrier organization and of CSF cytokine content. They also indicate that a direct effect of bilirubin on the vascular system organization, brain barriers morphological integrity, and inflammatory response of the choroid plexus-CSF system is not involved in the alteration of brain functions induced by severe neonatal jaundice.


Assuntos
Barreira Hematoencefálica , Icterícia Neonatal , Animais , Bilirrubina/metabolismo , Barreira Hematoencefálica/metabolismo , Líquido Cefalorraquidiano/metabolismo , Plexo Corióideo/metabolismo , Citocinas/metabolismo , Humanos , Hiperbilirrubinemia/metabolismo , Recém-Nascido , Icterícia Neonatal/metabolismo , Ratos , Ratos Gunn , Sacarose
8.
Acta Histochem ; 124(6): 151918, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35724482

RESUMO

BACKGROUND AND PURPOSE: Hyperbilirubinemia is a common condition in neonates that is associated with poor neurodevelopmental outcomes. Although studies have proposed that calycosin has a neuroprotective effect, the exact molecular mechanism underlying calycosin treatment of hyperbilirubinemia remains elusive. To fill this gap, we analyzed the mechanism of calycosin treatment in hyperbilirubinemia model mice. METHOD: Thirty neonatal mice were randomly divided into wide type (WT), Ugt1-/- and calycosin treatment group. Neuronal damage was observed with Nissl staining. Immunofluorescence staining were carried out to determine DNA damage repair and neurodegeneration. Oxidative stress was investigated by immunostaining with 4-hydroxynonenal (4-HNE). Western blot (WB) and Qpcr were used to detect relative protein and mRNA expression levels. Mitochondrial CI/CII activity of mitochondria was analyzed with a spectrophotometer. RESULT: The total bilirubin concentration was significantly higher in Ugt1-/- group compared with WT, but calycosin treatment reduced concentration of bilirubin. The total bilirubin and bilirubin/albumin ratio were significantly higher at postnatal day 4 compared with day 2. Calycosin treatment reduced serum bilirubin concentration and bilirubin/albumin ratio. After calycosin treatment, Nissl body count increased, apoptosis-related protein was downregulated and 4-HNE level decreased. Compared with Ugt-/- group, calycosin treatment increased neurons (NeuN+) and calbindin positive cells and decreased fluorojade C(FJC)positive neurons in WT group. In mitochondria, calycosin alleviated mitochondrial electron transport chain dysfunction in Ugt1-/- mice. CONCLUSION: We demonstrated that the mechanism of calycosin treatment on hyperbilirubinemia-induced Ugt1-/- was associated mainly with antioxidant effects, antiapoptosis and inhibition of normal mitochondrial function.


Assuntos
Glucuronosiltransferase , Hiperbilirrubinemia , Albuminas/metabolismo , Albuminas/farmacologia , Animais , Apoptose , Bilirrubina/metabolismo , Bilirrubina/farmacologia , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Glucuronosiltransferase/farmacologia , Hiperbilirrubinemia/complicações , Hiperbilirrubinemia/metabolismo , Isoflavonas , Camundongos , Mitocôndrias/metabolismo , Estresse Oxidativo
9.
J Physiol ; 600(8): 1889-1911, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35156712

RESUMO

Circulating bilirubin is associated with reduced serum cholesterol concentrations in humans and in hyperbilirubinaemic Gunn rats. However, mechanisms contributing to hypocholesterolaemia remain unknown. Therefore, this study aimed to investigate cholesterol synthesis, transport and excretion in mutant Gunn rats. Adult Gunn and control rats were assessed for daily faecal sterol excretion using metabolic cages, and water was supplemented with [1-13 C]-acetate to determine cholesterol synthesis. Bile was collected to measure biliary lipid secretion. Serum and liver were collected for biochemical analysis and for gene/protein expression using RT-qPCR and western blot, respectively. Additionally, serum was collected and analysed from juvenile rats. A significant interaction of sex, age and phenotype on circulating lipids was found with adult female Gunn rats reporting significantly lower cholesterol and phospholipids. Female Gunn rats also demonstrated elevated cholesterol synthesis, greater biliary lipid secretion and increased total faecal cholesterol and bile acid excretion. Furthermore, they possessed increased hepatic low-density lipoprotein (LDL) receptor and SREBP2 expression. In contrast, there were no changes to sterol metabolism in adult male Gunn rats. This is the first study to demonstrate elevated faecal sterol excretion in female hyperbilirubinaemic Gunn rats. Increased sterol excretion creates a negative intestinal sterol balance that is compensated for by increased cholesterol synthesis and LDL receptor expression. Therefore, reduced circulating cholesterol is potentially caused by increased hepatic uptake via the LDL receptor. Future studies are required to further evaluate the sexual dimorphism of this response and whether similar findings occur in females with benign unconjugated hyperbilirubinaemia (Gilbert's syndrome). KEY POINTS: Female adult hyperbilirubinaemic (Gunn) rats demonstrated lower circulating cholesterol, corroborating human studies that report a negative association between bilirubin and cholesterol concentrations. Furthermore, female Gunn rats had elevated sterol excretion creating a negative intestinal sterol balance that was compensated for by elevated cholesterol synthesis and increased hepatic low-density lipoprotein (LDL) receptor expression. Therefore, elevated LDL receptor expression potentially leads to reduced circulating cholesterol levels in female Gunn rats providing an explanation for the hypocholesterolaemia observed in humans with elevated bilirubin levels. This study also reports a novel interaction of sex with the hyperbilirubinaemic phenotype on sterol metabolism because changes were only reported in females and not in male Gunn rats. Future studies are required to further evaluate the sexual dimorphism of this response and whether similar findings occur in females with benign unconjugated hyperbilirubinaemia (Gilbert's syndrome).


Assuntos
Doença de Gilbert , Hipercolesterolemia , Animais , Bilirrubina/metabolismo , Colesterol/metabolismo , Feminino , Doença de Gilbert/metabolismo , Hiperbilirrubinemia/metabolismo , Hipercolesterolemia/metabolismo , Lipoproteínas LDL/metabolismo , Fígado/metabolismo , Masculino , Ratos , Ratos Gunn , Receptores de LDL/genética , Receptores de LDL/metabolismo , Caracteres Sexuais , Esteróis/metabolismo
10.
Indian J Med Microbiol ; 39(3): 320-322, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33617927

RESUMO

A 52 year old previously healthy woman from Mumbai presented with fever and jaundice of 10 days duration. At admission, she was jaundiced with tachycardia, tachypnea, hypoxia, hypotension, conjunctival congestion and mild erythematous flush over the skin. She had very high WBC counts and CRP's with direct hyperbilirubinemia and azotemia. Investigations for infectious causes of fever were negative. RT-PCR for SARS-CoV-2 in the nasopharynx was negative. However her SARS-CoV-2 antibodies were reactive. She also had echocardiographic and biochemical evidence of cardiac dysfunction. The diagnosis of Multisystem inflammatory syndrome-Adult (MIS-A) was thus established. She rapidly improved with intravenous immunoglobulin (2 gm/kg) and high dose steroids.


Assuntos
Febre/etiologia , Icterícia/etiologia , Azotemia/tratamento farmacológico , Azotemia/metabolismo , Azotemia/microbiologia , COVID-19/microbiologia , Ecocardiografia , Febre/tratamento farmacológico , Febre/metabolismo , Humanos , Hiperbilirrubinemia/tratamento farmacológico , Hiperbilirrubinemia/metabolismo , Hiperbilirrubinemia/microbiologia , Imunoglobulinas/uso terapêutico , Icterícia/tratamento farmacológico , Icterícia/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/patogenicidade , Esteroides/metabolismo
11.
Am J Physiol Endocrinol Metab ; 320(2): E191-E207, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33284088

RESUMO

Recent research on bilirubin, a historically well-known waste product of heme catabolism, suggests an entirely new function as a metabolic hormone that drives gene transcription by nuclear receptors. Studies are now revealing that low plasma bilirubin levels, defined as "hypobilirubinemia," are a possible new pathology analogous to the other end of the spectrum of extreme hyperbilirubinemia seen in patients with jaundice and liver dysfunction. Hypobilirubinemia is most commonly seen in patients with metabolic dysfunction, which may lead to cardiovascular complications and possibly stroke. We address the clinical significance of low bilirubin levels. A better understanding of bilirubin's hormonal function may explain why hypobilirubinemia might be deleterious. We present mechanisms by which bilirubin may be protective at mildly elevated levels and research directions that could generate treatment possibilities for patients with hypobilirubinemia, such as targeting of pathways that regulate its production or turnover or the newly designed bilirubin nanoparticles. Our review here calls for a shift in the perspective of an old molecule that could benefit millions of patients with hypobilirubinemia.


Assuntos
Bilirrubina/sangue , Bilirrubina/fisiologia , Metabolismo Energético , Hormônios/fisiologia , Animais , Bilirrubina/deficiência , Metabolismo Energético/genética , Regulação da Expressão Gênica , Doença de Gilbert/sangue , Doença de Gilbert/genética , Doença de Gilbert/metabolismo , Heme/metabolismo , Humanos , Hiperbilirrubinemia/complicações , Hiperbilirrubinemia/genética , Hiperbilirrubinemia/metabolismo , Redes e Vias Metabólicas/genética , PPAR alfa/metabolismo , PPAR alfa/fisiologia
12.
Exp Biol Med (Maywood) ; 245(12): 1049-1057, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32264693

RESUMO

IMPACT STATEMENT: Short bowel syndrome is associated with significant comorbidities and mortality. This study is important as unlike current systems, it provides a validated piglet model which mirrors anatomical, histological, and serological characteristics observed in human SBS. This model can be used to advance knowledge into mechanistic pathways and therapeutic modalities to improve outcomes for SBS patients. This study is novel in that in addition to significant reduction in the remnant bowel and noted liver disease, we also developed a method to emulate ileocecal valve resection and described gut adaptive responses which has important clinical implications in humans.


Assuntos
Colo/patologia , Colo/cirurgia , Íleo/patologia , Íleo/cirurgia , Síndrome do Intestino Curto/patologia , Síndrome do Intestino Curto/cirurgia , Anastomose Cirúrgica/métodos , Animais , Animais Recém-Nascidos , Colo/metabolismo , Modelos Animais de Doenças , Hiperbilirrubinemia/metabolismo , Hiperbilirrubinemia/patologia , Íleo/metabolismo , Fígado/metabolismo , Fígado/patologia , Nutrientes/metabolismo , Síndrome do Intestino Curto/metabolismo , Suínos
13.
Fetal Pediatr Pathol ; 39(2): 124-131, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31322449

RESUMO

Aims: We investigated the relationship between total serum bilirubin (TSB) and carboxyhemoglobin (COHb) in term neonates with detected and treated hemolysis within a particular time frame with the aim of augmenting the case for early diagnosis and prevention of morbidity in hemolysis. Materials and Methods: The study group comprised term newborns who were above the 95th percentile for TSB, underwent intravenous immunoglobulin (IVIG) or applied total exchange transfusion due to hemolysis. Newborns without hemolysis who were above the 95th TSB percentile and required phototherapy comprised the control group. Results: At a cutoff COHb value of 2.2%, 80.8% sensitivity, 95.5% specificity, 18.1 likelihood ratio, positive predictive value of 94.7%, and negative predictive value of 83.2% were identified. Conclusion: We found that COHb is a sensitive and specific method for detecting hemolysis, and it can be used in the early diagnosis of hemolytic diseases causing early and severe hyperbilirubinemia.


Assuntos
Carboxihemoglobina/metabolismo , Hemólise/fisiologia , Hiperbilirrubinemia/diagnóstico , Sensibilidade e Especificidade , Sistema ABO de Grupos Sanguíneos/metabolismo , Feminino , Humanos , Hiperbilirrubinemia/metabolismo , Recém-Nascido , Icterícia Neonatal/diagnóstico , Icterícia Neonatal/metabolismo , Masculino
14.
Pediatr Res ; 87(2): 327-331, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31600770

RESUMO

Despite the availability of successful prevention strategies to prevent excessive hyperbilirubinemia, the neurological sequelae of bilirubin neurotoxicity (BNTx) still occur throughout the world. Kernicterus, encephalopathy due to BNTx, is now understood to be a spectrum of severity and phenotypes known as kernicterus spectrum disorder (KSD). A better understanding of the selective neuropathology and molecular biology of BNTx and using consistent clinical definitions of KSDs as outcome measure can lead to more accurately predicting the risk and causes of BNTx and KSDs. In Part I of our two-part review, we will summarize current and recent advances in the understanding of the selective neuropathology and molecular biology of the disease. Herein we emphasize the role of unbound, free unconjugated bilirubin as well as genetic contributions to the susceptibility BNTx and the development of KSDs. In Part II, we focus on current and possible novel methods to prevent BNTx and ABE and treat ABE and KSDs.


Assuntos
Bilirrubina/metabolismo , Hiperbilirrubinemia/complicações , Kernicterus/etiologia , Neurônios/metabolismo , Síndromes Neurotóxicas/etiologia , Animais , Bilirrubina/sangue , Criança , Desenvolvimento Infantil , Pré-Escolar , Predisposição Genética para Doença , Humanos , Hiperbilirrubinemia/sangue , Hiperbilirrubinemia/genética , Hiperbilirrubinemia/metabolismo , Lactente , Recém-Nascido , Kernicterus/genética , Kernicterus/metabolismo , Kernicterus/fisiopatologia , Degeneração Neural , Neurogênese , Neurônios/patologia , Síndromes Neurotóxicas/genética , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/fisiopatologia , Fenótipo , Fatores de Risco
15.
Am J Physiol Gastrointest Liver Physiol ; 318(1): G41-G52, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31604032

RESUMO

Infants receiving long-term parenteral nutrition (PN) develop PN-associated liver disease (PNALD). We previously (Ng K et al. JPEN J Parenter Enteral Nutr 40: 656-671, 2016. doi:10.1177/0148607114567900.) showed that PN containing soy-based lipid supplemented with vitamin E (α-tocopherol) prevents the development of PNALD. We hypothesize that this occurs via vitamin E activation of pregnane X receptor (PXR)-mediated pathways involved in bile acid metabolism. Neonatal piglets received PN for 14 days containing Intralipid (IL; soy-based lipid emulsion), IL supplemented with 12.6 mg·kg-1·day-1 vitamin E (VITE), or IL with 10 mg·kg-1·day-1 Rifadin IV (RIF), a PXR agonist. Pigs treated with IL and VITE, but not RIF, developed cholestasis and hyperbilirubinemia, markers of liver disease. The hepatic PXR target genes CYP3A29 and UGT1A6 increased during RIF treatment. RIF also modestly increased metabolism of chenodeoxycholic acid to the more hydrophilic bile acid hyocholic acid. Serum fibroblast growth factor (FGF)-19, a key regulator in suppressing hepatic bile acid synthesis, significantly increased in the RIF group. We conclude rifampicin modified markers of PNALD development by increased metabolism of bile acids and potentially suppressed bile acid synthesis. Vitamin E was ineffective at high lipid doses in preventing PNALD.NEW & NOTEWORTHY Intravenous vitamin E and rifampicin were administered to neonatal piglets receiving parenteral nutrition to determine their efficacy in reducing the progression of parenteral nutrition-associated liver disease (PNALD). Rifampicin increased serum FGF-19 concentrations and synthesis of the bile acid hyocholic acid which led to a reduction of PNALD parameters at 2 wk of administration. This result has potential clinical implications for the use of rifampicin as a safe and inexpensive treatment for short-term development of PNALD.


Assuntos
Ácidos e Sais Biliares/metabolismo , Emulsões Gordurosas Intravenosas , Hepatopatias/prevenção & controle , Fígado/efeitos dos fármacos , Nutrição Parenteral , Fosfolipídeos , Receptor de Pregnano X/agonistas , Rifampina/farmacologia , Óleo de Soja , Vitamina E/farmacologia , Animais , Animais Recém-Nascidos , Ácidos e Sais Biliares/biossíntese , Colestase/etiologia , Colestase/metabolismo , Colestase/prevenção & controle , Citocromo P-450 CYP3A/metabolismo , Modelos Animais de Doenças , Emulsões , Glucuronosiltransferase/metabolismo , Hiperbilirrubinemia/etiologia , Hiperbilirrubinemia/metabolismo , Hiperbilirrubinemia/prevenção & controle , Fígado/metabolismo , Fígado/patologia , Hepatopatias/etiologia , Hepatopatias/metabolismo , Hepatopatias/patologia , Receptor de Pregnano X/metabolismo , Transdução de Sinais , Sus scrofa
16.
Pediatr Res ; 87(2): 332-337, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31581172

RESUMO

Previously in Part I of this two-part review, we discussed the current and recent advances in the understanding of the molecular biology and neuropathology of bilirubin neurotoxicity (BNTx). Here in Part II, we summarize current treatment options available to treat the severely jaundiced infants to prevent significant brain damage and improve clinical outcomes. In addition, we review potential novel therapies that are in various stages of research and development. We will emphasize treatments for both prevention and treatment of both acute bilirubin encephalopathy (ABE) and kernicterus spectrum disorders (KSDs), highlighting the treatment of the most disabling neurological sequelae of children with mild-to-severe KSDs whose "rare disease" status often means they are overlooked by the clinical research community at large. As with other secondary dystonias, treatment of the dystonic motor symptoms in kernicterus is the greatest clinical challenge.


Assuntos
Bilirrubina/metabolismo , Hiperbilirrubinemia/terapia , Kernicterus/prevenção & controle , Neurônios/metabolismo , Síndromes Neurotóxicas/prevenção & controle , Animais , Bilirrubina/sangue , Criança , Desenvolvimento Infantil , Pré-Escolar , Humanos , Hiperbilirrubinemia/sangue , Hiperbilirrubinemia/complicações , Hiperbilirrubinemia/metabolismo , Lactente , Recém-Nascido , Kernicterus/etiologia , Kernicterus/metabolismo , Kernicterus/fisiopatologia , Degeneração Neural , Neurogênese , Neurônios/patologia , Síndromes Neurotóxicas/etiologia , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/fisiopatologia , Resultado do Tratamento
17.
Pediatr Res ; 87(1): 17-25, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31493769

RESUMO

The molecular and cellular events leading to bilirubin-induced neurotoxicity, the mechanisms regulating liver and intestine expression in neonates, and alternative pathways of bilirubin catabolism remain incompletely defined. To answer these questions, researchers have developed a number of model systems to closely recapitulate the main characteristics of the disease, ranging from tissue cultures to engineered mouse models. In the present review we describe in vitro, ex vivo, and in vivo models developed to study bilirubin metabolism and neurotoxicity, with a special focus on the use of engineered animal models. In addition, we discussed the most recent studies related to potential therapeutic approaches to treat neonatal hyperbilirubinemia, ranging from anti-inflammatory drugs, activation of nuclear receptor pathways, blockade of bilirubin catabolism, and stimulation of alternative bilirubin-disposal pathways.


Assuntos
Bilirrubina/metabolismo , Hiperbilirrubinemia/sangue , Hiperbilirrubinemia/complicações , Neurônios/metabolismo , Síndromes Neurotóxicas/etiologia , Animais , Bilirrubina/sangue , Células Cultivadas , Modelos Animais de Doenças , Humanos , Hiperbilirrubinemia/genética , Hiperbilirrubinemia/metabolismo , Camundongos Transgênicos , Neurônios/patologia , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia , Transdução de Sinais
18.
Xenobiotica ; 50(1): 64-76, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31092094

RESUMO

The role that the phase-II reaction, glucuronidation, plays in the biotransformation of endo and xenobiotics is discussed with particular emphasis given to the UGT1A1 isoenzyme. This individual isoenzyme is responsible for both the mono and di-glucuronidation of bilirubin together with the glucuronidation of a number of xenobiotics of clinical interest (irinotecan, belinostat, atazanavir, pegvisomant).The review then discusses the roles that the various allelic variants of the UGT1A1 gene play in bilirubin metabolism and in particular how these allelic variants are involved in the clinical manifestation of the diseases of GS, CN1 and CN2.The review concludes with the roles that the UGT1A1*28 and UGT1A1*6 alleles play in adverse drug reactions (decreased glucuronidation of irinotecan, belinostat, atazanavir, pegvisomant) leading to increased exposure, reduced clearance and neutropenia (irinotecan, belinostat), increased risk for jaundice and hyperbilirubinaemia (atazanavir) and liver toxicity (pegvisomant) before discussing the future role of UGT1A1 in personalised medicine.


Assuntos
Glucuronosiltransferase/genética , Alelos , Bilirrubina , Genótipo , Glucuronosiltransferase/metabolismo , Humanos , Ácidos Hidroxâmicos/metabolismo , Hiperbilirrubinemia/metabolismo , Irinotecano/metabolismo , Sulfonamidas/metabolismo
19.
Biol Trace Elem Res ; 195(1): 1-8, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31317471

RESUMO

This study was performed to evaluate the effects of selenium supplementation on gene expression related to insulin and lipid metabolism, and pregnancy outcomes in patients with gestational diabetes mellitus (GDM). The current randomized, double-blind, placebo-controlled clinical trial was conducted in 36 patients with GDM. Participants were randomly divided into two groups to intake either 200 µg/day selenium supplements as selenium yeast or placebo (n = 18 each group) for 6 weeks. Selenium supplementation upregulated peroxisome proliferator-activated receptor gamma (P = 0.03) and glucose transporter 1 (GLUT-1) (P = 0.01) in lymphocytes of subjects with GDM compared with the placebo. Selenium supplementation did not affect gene expression of low-density lipoprotein receptor (LDLR) and lipoprotein(a) [Lp(a)]. Supplementation with selenium had a significant decrease in incidence of newborns' hyperbilirubinemia (5.6% vs. 33.3%, P = 0.03) and newborns' hospitalization (5.6% vs. 33.3%, P = 0.03) compared with the placebo. Overall, we found that selenium supplementation for 6 weeks among patients with GDM significantly increased PPAR-γ and GLUT-1 expression, but did not affect gene expression of LDLR and LP(a). It also reduced incidence of newborns' hyperbilirubinemia and newborns' hospitalization. Clinical trial registration number: http://www.irct.ir: IRCT20170513033941N35.


Assuntos
Diabetes Gestacional/tratamento farmacológico , Insulina/genética , Metabolismo dos Lipídeos/genética , Resultado da Gravidez/genética , Selênio/farmacologia , Diabetes Gestacional/genética , Diabetes Gestacional/metabolismo , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Expressão Gênica/efeitos dos fármacos , Hospitalização , Humanos , Hiperbilirrubinemia/tratamento farmacológico , Hiperbilirrubinemia/genética , Hiperbilirrubinemia/metabolismo , Recém-Nascido , Insulina/metabolismo , Gravidez , Selênio/administração & dosagem
20.
Pediatr Blood Cancer ; 67(2): e28063, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31736183

RESUMO

Conjugated hyperbilirubinemia (CHB) and liver transaminase elevation are known complications of acute lymphoblastic leukemia (ALL) therapy, but host risk factors are poorly understood. Among 373 children diagnosed with ALL between 2011 and 2016, clinically significant CHB and transaminase elevation were observed in 15 (4.0%) and 12 (3.2%) children, respectively, during induction and consolidation. Body mass index ≥95th percentile (odds ratio 9.20, 95% confidence interval 2.56-32.96) was the only host factor independently associated with CHB, and no host factors were associated with transaminase elevation. Obese patients warrant closer monitoring of hepatic function to facilitate early intervention prior to the development of severe, adverse hepatic events.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores Tumorais/análise , Hiperbilirrubinemia/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Hiperbilirrubinemia/induzido quimicamente , Hiperbilirrubinemia/metabolismo , Hiperbilirrubinemia/patologia , Incidência , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Prognóstico , Fatores de Risco , Texas/epidemiologia , Adulto Jovem
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