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1.
PLoS One ; 19(7): e0303786, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38950046

RESUMO

A prevailing animal model currently used to study severe human diseases like obstructive cholestasis, primary biliary or sclerosing cholangitis, biliary atresia, and acute liver injury is the common bile duct ligation (cBDL). Modifications of this model include ligation of the left hepatic bile duct (pBDL) or ligation of the left bile duct with the corresponding left hepatic artery (pBDL+pAL). Both modifications induce cholestasis only in the left liver lobe. After induction of total or partial cholestasis in mice, the well-being of these animals was evaluated by assessing burrowing behavior, body weight, and a distress score. To compare the pathological features of these animal models, plasma levels of liver enzymes, bile acids, bilirubin, and within the liver tissue, necrosis, fibrosis, inflammation, as well as expression of genes involved in the synthesis or transport of bile acids were assessed. The survival rate of the animals and their well-being was comparable between pBDL+pAL and pBDL. However, surgical intervention by pBDL+pAL caused confluent necrosis and collagen depositions at the edge of necrotic tissue, whereas pBDL caused focal necrosis and fibrosis in between portal areas. Interestingly, pBDL animals had a higher survival rate and their well-being was significantly improved compared to cBDL animals. On day 14 after cBDL liver aspartate, as well as alanine aminotransferase, alkaline phosphatase, glutamate dehydrogenase, bile acids, and bilirubin were significantly elevated, but only glutamate dehydrogenase activity was increased after pBDL. Thus, pBDL may be primarily used to evaluate local features such as inflammation and fibrosis or regulation of genes involved in bile acid synthesis or transport but does not allow to study all systemic features of cholestasis. The pBDL model also has the advantage that fewer mice are needed, because of its high survival rate, and that the well-being of the animals is improved compared to the cBDL animal model.


Assuntos
Colestase , Modelos Animais de Doenças , Fígado , Animais , Ligadura , Camundongos , Colestase/metabolismo , Colestase/patologia , Fígado/metabolismo , Fígado/patologia , Ductos Biliares/cirurgia , Ductos Biliares/patologia , Ductos Biliares/metabolismo , Ácidos e Sais Biliares/metabolismo , Masculino , Bilirrubina/sangue , Bilirrubina/metabolismo , Camundongos Endogâmicos C57BL , Ducto Colédoco/cirurgia
2.
Biomed Pharmacother ; 175: 116644, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38692057

RESUMO

Transmembrane drug transporters can be important determinants of the pharmacokinetics, efficacy, and safety profiles of drugs. To investigate the potential cooperative and/or counteracting interplay of OATP1A/1B/2B1 uptake transporters and ABCB1 and ABCG2 efflux transporters in physiology and pharmacology, we generated a new mouse model (Bab12), deficient for Slco1a/1b, Slco2b1, Abcb1a/1b and Abcg2. Bab12 mice were viable and fertile. We compared wild-type, Slco1a/1b/2b1-/-, Abcb1a/1b;Abcg2-/- and Bab12 strains. Endogenous plasma conjugated bilirubin levels ranked as follows: wild-type = Abcb1a/1b;Abcg2-/- << Slco1a/1b/2b1-/- < Bab12 mice. Plasma levels of rosuvastatin and fexofenadine were elevated in Slco1a/1b/2b1-/- and Abcb1a/1b;Abcg2-/- mice compared to wild-type, and dramatically increased in Bab12 mice. Although systemic exposure of larotrectinib and repotrectinib was substantially increased in the separate multidrug transporter knockout strains, no additive effects were observed in the combination Bab12 mice. Significantly higher plasma exposure of fluvastatin and pravastatin was only found in Slco1a/1b/2b1-deficient mice. However, noticeable transport by Slco1a/1b/2b1 and Abcb1a/1b and Abcg2 across the BBB was observed for fluvastatin and pravastatin, respectively, by comparing Bab12 mice with Abcb1a/1b;Abcg2-/- or Slco1a/1b/2b1-/- mice. Quite varying behavior in plasma exposure of erlotinib and its metabolites was observed among these strains. Bab12 mice revealed that Abcb1a/1b and/or Abcg2 can contribute to conjugated bilirubin elimination when Slco1a/1b/2b1 are absent. Our results suggest that the interplay of Slco1a/1b/2b1, Abcb1a/1b, and Abcg2 could markedly affect the pharmacokinetics of some, but not all drugs and metabolites. The Bab12 mouse model will represent a useful tool for optimizing drug development and clinical application, including efficacy and safety.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Bilirrubina , Camundongos Knockout , Transportadores de Ânions Orgânicos , Animais , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Bilirrubina/sangue , Bilirrubina/metabolismo , Camundongos , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Transportadores de Ânions Orgânicos/genética , Transportador 1 de Ânion Orgânico Específico do Fígado/metabolismo , Transportador 1 de Ânion Orgânico Específico do Fígado/genética , Terfenadina/farmacocinética , Terfenadina/análogos & derivados , Masculino , Transporte Biológico , Rosuvastatina Cálcica/farmacocinética , Rosuvastatina Cálcica/farmacologia , Camundongos Endogâmicos C57BL
3.
J Biol Chem ; 300(6): 107340, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705390

RESUMO

Triclosan (TCS) is an antimicrobial toxicant found in a myriad of consumer products and has been detected in human tissues, including breastmilk. We have evaluated the impact of lactational TCS on UDP-glucuronosyltransferase 1A1 (UGT1A1) expression and bilirubin metabolism in humanized UGT1 (hUGT1) neonatal mice. In hUGT1 mice, expression of the hepatic UGT1A1 gene is developmentally delayed resulting in elevated total serum bilirubin (TSB) levels. We found that newborn hUGT1 mice breastfed or orally treated with TCS presented lower TSB levels along with induction of hepatic UGT1A1. Lactational and oral treatment by gavage with TCS leads to the activation of hepatic nuclear receptors constitutive androstane receptor (CAR), peroxisome proliferator-activated receptor alpha (PPARα), and stress sensor, activating transcription factor 4 (ATF4). When CAR-deficient hUGT1 mice (hUGT1/Car-/-) were treated with TCS, TSB levels were reduced with a robust induction of hepatic UGT1A1, leaving us to conclude that CAR is not tied to UGT1A1 induction. Alternatively, when PPARα-deficient hUGT1 mice (hUGT1/Pparα-/-) were treated with TCS, hepatic UGT1A1 was not induced. Additionally, we had previously demonstrated that TCS is a potent inducer of ATF4, a transcriptional factor linked to the integrated stress response. When ATF4 was deleted in liver of hUGT1 mice (hUGT1/Atf4ΔHep) and these mice treated with TCS, we observed superinduction of hepatic UGT1A1. Oxidative stress genes in livers of hUGT1/Atf4ΔHep treated with TCS were increased, suggesting that ATF4 protects liver from excessive oxidative stress. The increase oxidative stress may be associated with superinduction of UGT1A1. The expression of ATF4 in neonatal hUGT1 hepatic tissue may play a role in the developmental repression of UGT1A1.


Assuntos
Fator 4 Ativador da Transcrição , Animais Recém-Nascidos , Bilirrubina , Glucuronosiltransferase , Fígado , PPAR alfa , Triclosan , Animais , Glucuronosiltransferase/metabolismo , Glucuronosiltransferase/genética , PPAR alfa/metabolismo , PPAR alfa/genética , Camundongos , Fator 4 Ativador da Transcrição/metabolismo , Fator 4 Ativador da Transcrição/genética , Triclosan/farmacologia , Humanos , Bilirrubina/farmacologia , Bilirrubina/metabolismo , Fígado/metabolismo , Fígado/efeitos dos fármacos , Camundongos Knockout , Feminino , Receptor Constitutivo de Androstano , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores Citoplasmáticos e Nucleares/genética
4.
Int J Mol Sci ; 25(10)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38791361

RESUMO

Newborn infants face a rapid surge of oxygen and a more protracted rise of unconjugated bilirubin after birth. Bilirubin has a strong antioxidant capacity by scavenging free radicals, but it also exerts direct toxicity. This study investigates whether cultured rat alveolar epithelial cells type II (AEC II) react differently to bilirubin under different oxygen concentrations. The toxic threshold concentration of bilirubin was narrowed down by means of a cell viability test. Subsequent analyses of bilirubin effects under 5% oxygen and 80% oxygen compared to 21% oxygen, as well as pretreatment with bilirubin after 4 h and 24 h of incubation, were performed to determine the induction of apoptosis and the gene expression of associated transcripts of cell death, proliferation, and redox-sensitive transcription factors. Oxidative stress led to an increased rate of cell death and induced transcripts of redox-sensitive signaling pathways. At a non-cytotoxic concentration of 400 nm, bilirubin attenuated oxidative stress-induced responses and possibly mediated cellular antioxidant defense by influencing Nrf2/Hif1α- and NFκB-mediated signaling pathways. In conclusion, the study demonstrates that rat AEC II cells are protected from oxidative stress-induced impairment by low-dose bilirubin.


Assuntos
Células Epiteliais Alveolares , Bilirrubina , Estresse Oxidativo , Estresse Oxidativo/efeitos dos fármacos , Animais , Bilirrubina/farmacologia , Bilirrubina/metabolismo , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/efeitos dos fármacos , Ratos , Sobrevivência Celular/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Antioxidantes/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Células Cultivadas , NF-kappa B/metabolismo
5.
Commun Biol ; 7(1): 621, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783088

RESUMO

Nuclear factor erythroid 2-related factor-2 (Nrf2) antioxidant signaling is involved in liver protection, but this generalization overlooks conflicting studies indicating that Nrf2 effects are not necessarily hepatoprotective. The role of Nrf2/heme oxygenase-1 (HO-1) in cholestatic liver injury (CLI) remains poorly defined. Here, we report that Nrf2/HO-1 activation exacerbates liver injury rather than exerting a protective effect in CLI. Inhibiting HO-1 or ameliorating bilirubin transport alleviates liver injury in CLI models. Nrf2 knockout confers hepatoprotection in CLI mice, whereas in non-CLI mice, Nrf2 knockout aggravates liver damage. In the CLI setting, oxidative stress activates Nrf2/HO-1, leads to bilirubin accumulation, and impairs mitochondrial function. High levels of bilirubin reciprocally upregulate the activation of Nrf2 and HO-1, while antioxidant and mitochondrial-targeted SOD2 overexpression attenuate bilirubin toxicity. The expression of Nrf2 and HO-1 is elevated in serum of patients with CLI. These results reveal an unrecognized function of Nrf2 signaling in exacerbating liver injury in cholestatic disease.


Assuntos
Bilirrubina , Colestase , Heme Oxigenase-1 , Camundongos Knockout , Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Transdução de Sinais , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Animais , Camundongos , Heme Oxigenase-1/metabolismo , Heme Oxigenase-1/genética , Colestase/metabolismo , Colestase/patologia , Colestase/genética , Humanos , Masculino , Bilirrubina/metabolismo , Bilirrubina/sangue , Camundongos Endogâmicos C57BL , Fígado/metabolismo , Fígado/lesões , Fígado/patologia , Modelos Animais de Doenças , Proteínas de Membrana
6.
Adv Sci (Weinh) ; 11(22): e2400713, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38593402

RESUMO

Osteoarthritis (OA) is a chronic inflammatory disease characterized by cartilage destruction, synovitis, and osteophyte formation. Disease-modifying treatments for OA are currently lacking. Because inflammation mediated by an imbalance of M1/M2 macrophages in the synovial cavities contributes to OA progression, regulating the M1 to M2 polarization of macrophages can be a potential therapeutic strategy. Basing on the inherent immune mechanism and pathological environment of OA, an immunoglobulin G-conjugated bilirubin/JPH203 self-assembled nanoparticle (IgG/BRJ) is developed, and its therapeutic potential for OA is evaluated. After intra-articular administration, IgG conjugation facilitates the recognition and engulfment of nanoparticles by the M1 macrophages. The internalized nanoparticles disassemble in response to the increased oxidative stress, and the released bilirubin (BR) and JPH203 scavenge reactive oxygen species (ROS), inhibit the nuclear factor kappa-B pathway, and suppress the activated mammalian target of rapamycin pathway, result in the repolarization of macrophages and enhance M2/M1 ratios. Suppression of the inflammatory environment by IgG/BRJ promotes cartilage protection and repair in an OA rat model, thereby improving therapeutic outcomes. This strategy of opsonization involving M1 macrophages to engulf carrier-free BR/JPH203 nanoparticles to suppress inflammation for OA therapy holds great potential for OA intervention and treatment.


Assuntos
Bilirrubina , Modelos Animais de Doenças , Inflamação , Macrófagos , Nanopartículas , Osteoartrite , Animais , Osteoartrite/imunologia , Osteoartrite/tratamento farmacológico , Macrófagos/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Ratos , Inflamação/imunologia , Bilirrubina/farmacologia , Bilirrubina/metabolismo , Masculino , Ratos Sprague-Dawley
7.
Artigo em Chinês | MEDLINE | ID: mdl-38604682

RESUMO

OBJECTIVE: To investigate the expression of neutrophil extracellular traps (NETs) and phagocytic function in the peripheral blood of patients with hepatic alveolar echinococcosis (HAE), and to examine their correlations with clinical inflamma tory indicators and liver functions. METHODS: A total of 50 patients with HAE admitted to Department of Hepatobiliary and Pancreatic Surgery, The Affiliated Hospital of Qinghai University from August 2022 to June 2023 were enrolled, while 50 age- and gender-matched healthy individuals from the Centre for Healthy Examinations of the hospital during the same period served as controls. The levels of NETs markers neutrophil myeloperoxidase (MPO) and neutrophil elastase (NE) were measured using enzyme-linked immunosorbent assay (ELISA). Peripheral blood neutrophils were isolated using density gradient centrifugation, stimulated in vitro using phorbol 12-myristate 13 acetate (PMA), and the levels of MPO and citrullination histone H3 (CitH3) released by neutrophils were quantified using flow cytometry. The phagocytic functions of neutrophils were examined using flow cytometry. In addition, the correlations of MPO and NE levels with clinical inflammatory indicators and liver biochemical indicators were examined using Spearman correlation analysis among HAE patients. RESULTS: The peripheral blood plasma MPOï¼»(417.15 ± 76.08) ng/mL vs. (255.70 ± 80.84) ng/mL; t = 10.28, P < 0.05ï¼½, NEï¼»(23.16 ± 6.75) ng/mL vs. (11.92 ± 3.17) ng/mL; t = 10.65, P < 0.05ï¼½and CitH3 levelsï¼»(33.93 ± 18.93) ng/mL vs. (19.52 ± 13.89) ng/mL; t = 4.34, P < 0.05ï¼½were all significantly higher among HAE patients than among healthy controls, and a lower phagocytosis rate of neutrophils was detected among HAE patients than among healthy controlsï¼»(70.85 ± 7.32)% vs. (94.04 ± 3.90)%; t = 20.18, P < 0.05ï¼½, and the ability to produce NETs by neutrophils was higher among HAE patients than among healthy controls following in vitro PMA stimulation. Pearson correlation analysis showed that the phagocytosis rate of neutrophils correlated negatively with platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), interleukin-6 (IL-6) level and C-reactive protein (CRP) level (rs = -0.515 to -0.392, all P values < 0.05), and the MPO and NE levels positively correlated with inflammatory markers NLR, PLR, CRP and IL-6 (rs = 0.333 to 0.445, all P values < 0.05) and clinical liver biochemical indicators aspartic transaminase, alanine aminotransferase, direct bilirubin and total bilirubin among HAE patients (rs = 0.290 to 0.628, all P values < 0.001). CONCLUSIONS: Excessive formation of NETs is found among HAE patients, which affects the phagocytic ability of neutrophils and results in elevated levels of inflammatory indicators. NETs markers may be promising novel biomarkers for early diagnosis, monitoring, and severity assessment of liver disease.


Assuntos
Equinococose Hepática , Armadilhas Extracelulares , Humanos , Armadilhas Extracelulares/metabolismo , Interleucina-6/metabolismo , Neutrófilos , Acetato de Tetradecanoilforbol/metabolismo , Bilirrubina/metabolismo
8.
Plant Cell Physiol ; 65(5): 762-769, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38466577

RESUMO

In heterotrophs, heme degradation produces bilirubin, a tetrapyrrole compound that has antioxidant activity. In plants, heme is degraded in plastids and is believed to be converted to phytochromobilin rather than bilirubin. Recently, we used the bilirubin-inducible fluorescent protein UnaG to reveal that plants produce bilirubin via a non-enzymatic reaction with NADPH. In the present study, we used an UnaG-based live imaging system to visualize bilirubin accumulation in Arabidopsis thaliana and Nicotiana benthamiana at the organelle and tissue levels. In chloroplasts, bilirubin preferentially accumulated in the stroma, and the stromal bilirubin level increased upon dark treatment. Investigation of intracellular bilirubin distribution in leaves and roots showed that it accumulated mostly in plastids, with low levels detected in the cytosol and other organelles, such as peroxisomes, mitochondria and the endoplasmic reticulum. A treatment that increased bilirubin production in chloroplasts decreased the bilirubin level in peroxisomes, implying that a bilirubin precursor is transported between the two organelles. At the cell and tissue levels, bilirubin showed substantial accumulation in the root elongation region but little or none in the root cap and guard cells. Intermediate bilirubin accumulation was observed in other shoot and root tissues, with lower levels in shoot tissues. Our data revealed the distribution of bilirubin in plants, which has implications for the transport and physiological function of tetrapyrroles.


Assuntos
Arabidopsis , Bilirrubina , Nicotiana , Raízes de Plantas , Arabidopsis/metabolismo , Nicotiana/metabolismo , Bilirrubina/metabolismo , Raízes de Plantas/metabolismo , Folhas de Planta/metabolismo , Cloroplastos/metabolismo , Peroxissomos/metabolismo
10.
Biomolecules ; 14(2)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38397392

RESUMO

Biliverdin reductase-A (BVRA) is a multi-functional enzyme with a multitude of important roles in physiologic redox homeostasis. Classically, BVRA is well known for converting the heme metabolite biliverdin to bilirubin, which is a potent antioxidant in both the periphery and the brain. However, BVRA additionally participates in many neuroprotective signaling cascades in the brain that preserve cognition. Here, we review the neuroprotective roles of BVRA and bilirubin in the brain, which together constitute a BVRA/bilirubin axis that influences healthy aging and cognitive function.


Assuntos
Bilirrubina , Biliverdina , Encéfalo , Neuroproteção , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Bilirrubina/metabolismo , Biliverdina/metabolismo , Encéfalo/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Animais , Camundongos
11.
Toxicology ; 502: 153719, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38181850

RESUMO

Per- and polyfluoroalkyl substances (PFASs), a group of synthetic chemicals that were once widely used for industrial purposes and in consumer products, are widely found in the environment and in human blood due to their extraordinary resistance to degradation. Once inside the body, PFASs can activate nuclear receptors such as PPARα and CAR. The present study aimed to investigate the impact of perfluorooctanoic acid (PFOA) and perfluorodecanoic acid (PFDA) on liver structure and functions, as well as bile acid homeostasis in mice. A single administration of 0.1 mmole/kg of PFDA, not PFOA, elevated serum ALT and bilirubin levels and caused cholestasis in WT mice. PFDA increased total and various bile acid species in serum but decreased them in the liver. Furthermore, in mouse livers, PFDA, not PFOA, down-regulated mRNA expression of uptake transporters (Ntcp, Oatp1a1, 1a4, 1b2, and 2b1) but induced efflux transporters (Bcrp, Mdr2, and Mrp2-4). In addition, PFDA, not PFOA, decreased Cyp7a1, 7b1, 8b1, and 27a1 mRNA expression in mouse livers with concomitant hepatic accumulation of cholesterol. In contrast, in PPARα-null mice, PFDA did not increase serum ALT, bilirubin, or total bile acids, but produced prominent hepatosteatosis; and the observed PFDA-induced expression changes of transporters and Cyps in WT mice were largely attenuated or abolished. In CAR-null mice, the observed PFDA-induced bile acid alterations in WT mice were mostly sustained. These results indicate that, at the dose employed, PFDA has more negative effects than PFOA on liver function. PPARα appears to play a major role in mediating most of PFDA-induced effects, which were absent or attenuated in PPARα-null mice. Lack of PPARα, however, exacerbated hepatic steatosis. Our findings indicate separated roles of PPARα in mediating the adaptive responses to PFDA: protective against hepatosteatosis but exacerbating cholestasis.


Assuntos
Caprilatos , Colestase , Ácidos Decanoicos , Fluorocarbonos , Humanos , Camundongos , Animais , Ácidos e Sais Biliares/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Neoplasias , Fígado , Fluorocarbonos/metabolismo , Camundongos Knockout , Bilirrubina/toxicidade , Bilirrubina/metabolismo , RNA Mensageiro/metabolismo
12.
Int J Biol Macromol ; 261(Pt 1): 129704, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272431

RESUMO

Chronic diabetic wounds pose a serious threat to human health and safety because of their refractory nature and high recurrence rates. The formation of refractory wounds is associated with wound microenvironmental factors such as increased expression of proinflammatory factors and oxidative stress. Bilirubin is a potent endogenous antioxidant, and morin is a naturally active substance that possesses anti-inflammatory and antioxidant effects. Both hold the potential for diabetic wound treatment by intervening in pathological processes. In this study, we developed bilirubin/morin-based carrier-free nanoparticles (BMn) to treat chronic diabetic wounds. In vitro studies showed that BMn could effectively scavenge overproduced reactive oxygen species and suppress elevated inflammation, thereby exerting a protective effect. BMn was then loaded into a collagen/polyvinyl alcohol gel (BMn@G) for an in vivo study to maintain a moist environment for the skin and convenient biomedical applications. BMn@G exhibits excellent mechanical properties, water retention capabilities, and in vivo safety. In type I diabetic mice, BMn@G elevated the expression of the anti-inflammatory factor IL-10 and concurrently diminished the expression of the proinflammatory factor TNF-α in the tissues surrounding the wounds. Furthermore, BMn@G efficiently mediated macrophage polarization from the M1-type to the M2-type, thereby fostering anti-inflammatory effects. Additionally, BMn@G facilitated the conversion of type III collagen fiber bundles to type I collagen fiber bundles, resulting in a more mature collagen fiber structure. This study provides a promising therapeutic alternative for diabetic wound healing.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus , Flavonas , Nanopartículas , Camundongos , Humanos , Animais , Álcool de Polivinil/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/complicações , Bilirrubina/metabolismo , Cicatrização , Colágeno/química , Inflamação/patologia , Anti-Inflamatórios/uso terapêutico , Flavonoides/uso terapêutico , Estresse Oxidativo , Hidrogéis/uso terapêutico , Diabetes Mellitus/tratamento farmacológico
13.
J Am Chem Soc ; 146(2): 1603-1611, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38165253

RESUMO

Bilirubin is the principal product of heme catabolism. High concentrations of the pigment are neurotoxic, yet slightly elevated levels are beneficial. Being a potent antioxidant, oxidative transformations of bilirubin occur in vivo and lead to various oxidized fragments. The mechanisms of their formation, intrinsic biological activities, and potential roles in human pathophysiology are poorly understood. Degradation methods have been used to obtain samples of bilirubin oxidation products for research. Here, we report a complementary, fully synthetic method of preparation. Our strategy leverages repeating substitution patterns in the parent tetracyclic pigment. Functionalized ready-to-couple γ-lactone, γ-lactam, and pyrrole monocyclic building blocks were designed and efficiently synthesized. Subsequent modular combinations, supported by metal-catalyzed borylation and cross-coupling chemistries, translated into the concise assembly of the structurally diverse bilirubin oxidation products (BOXes, propentdyopents, and biopyrrins). The discovery of a new photoisomer of biopyrrin A named lumipyrrin is reported. Synthetic bilirubin oxidation products made available in sufficient purity and quantity will support future in vitro and in vivo investigations.


Assuntos
Bilirrubina , Pirróis , Humanos , Bilirrubina/metabolismo , Oxirredução , Estresse Oxidativo
14.
In Vitro Cell Dev Biol Anim ; 60(2): 161-171, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38216855

RESUMO

Neonatal jaundice is one of the most common disorders in the first 2 wk after birth. Unconjugated bilirubin (UCB) is neurotoxic and can cause neurological dysfunction; however, the underlying mechanisms remain unclear. Neurogenesis, neuronal growth, and synaptogenesis are exuberant in the early postnatal stage. In this study, the impact of UCB on neuritogenesis and synaptogenesis in the early postnatal stage was evaluated both in vitro and in vivo. Primary culture neuronal stem and progenitor cells (NSPCs) were treated with UCB during differentiation, and then the neurite length and synapse puncta were measured. In the bilirubin encephalopathy (BE) animal model, DCX+-marked developing neurons were used to detect apical length and dendritic arborization. According to the data, UCB significantly reduced neurite length and synapse density, as well as decreased the apical dendrite length and dendritic arborization. Furthermore, the NMDAR subunit NR2B was downregulated in NSPCs, while pCREB expression in the hippocampus progressively decreased during disease progression in the BE model. Next, we tested the expression of NR2B, pCREB, mBDNF, and p-mTOR in NSPCs in vitro, and found that UCB treatment reduced the expression of these proteins. In summary, this suggests that UCB causes chronic neurological impairment and is related to the inhibition of NMDAR-CREB-BDNF signaling in NSPCs, which is associated with reduced neuritogenesis and synaptogenesis. This finding may inspire the development of novel pharmaceuticals and treatments.


Assuntos
Bilirrubina , Drogas Veterinárias , Animais , Bilirrubina/farmacologia , Bilirrubina/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Células Cultivadas , Drogas Veterinárias/metabolismo , Neurônios/metabolismo , Neurogênese , Células-Tronco/metabolismo
15.
Nat Microbiol ; 9(1): 173-184, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38172624

RESUMO

Metabolism of haem by-products such as bilirubin by humans and their gut microbiota is essential to human health, as excess serum bilirubin can cause jaundice and even neurological damage. The bacterial enzymes that reduce bilirubin to urobilinogen, a key step in this pathway, have remained unidentified. Here we used biochemical analyses and comparative genomics to identify BilR as a gut-microbiota-derived bilirubin reductase that reduces bilirubin to urobilinogen. We delineated the BilR sequences from similar reductases through the identification of key residues critical for bilirubin reduction and found that BilR is predominantly encoded by Firmicutes species. Analysis of human gut metagenomes revealed that BilR is nearly ubiquitous in healthy adults, but prevalence is decreased in neonates and individuals with inflammatory bowel disease. This discovery sheds light on the role of the gut microbiome in bilirubin metabolism and highlights the significance of the gut-liver axis in maintaining bilirubin homeostasis.


Assuntos
Bilirrubina , Microbioma Gastrointestinal , Recém-Nascido , Adulto , Humanos , Bilirrubina/metabolismo , Urobilinogênio/metabolismo , Fígado/metabolismo , Bactérias/genética , Bactérias/metabolismo
16.
Bioorg Chem ; 143: 106979, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37995646

RESUMO

FXR agonistic activity screening was conducted based on natural product resources containing 38 structurally diverse sesquiterpenoids isolated from Xylopia vielana. Among them, 34 undescribed sesquiterpenoids with 5 different skeleton types were first characterized by HRESIMS, NMR data, ECD calculations and X-ray crystallographic analysis. High-content screening for FXR agonistic activity of these compounds demonstrated that 13 compounds could activate FXR. Then molecular docking results suggested that hydrogen bonding and hydrophobic interactions might contribute to the main interaction of active compounds with FXR. The preliminary structure-activity relationships (SARs) of those isolates were also discussed. The most potent compound 27 significantly elevated the transcriptional activity of the FXR target gene BSEP promoter (EC50 = 14.26 µM) by a dual-luciferase reporter assay. Western blotting indicated that compound 27 activated the FXR-associated pathway, thereby upregulating SHP and BSEP expression, and downregulating CYP7A1 and NTCP expression. We further revealed that FXR was the target protein of compound 27 through diverse target validation methods, including CETSA, SIP, and DARTS under the intervention of temperature, organic reagents and protease. Pharmacological in vivo experiments showed that compound 27 effectively ameliorated α-naphthyl isothiocyanate (ANIT)-induced cholestasis in mice, as evidenced by the ameliorative histopathology of the liver and the decrease in biochemical markers: alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin (TBIL), direct bilirubin (DBIL), and total bile acid (TBA). This work showed a practical strategy for the discovery of new FXR agonists from natural products and provided potential insights for sesquiterpenoids as FXR agonist lead compounds.


Assuntos
Colestase , Sesquiterpenos , Camundongos , Animais , Simulação de Acoplamento Molecular , Fígado/metabolismo , Colestase/genética , Colestase/metabolismo , Colestase/prevenção & controle , Ácidos e Sais Biliares/metabolismo , Bilirrubina/metabolismo , Sesquiterpenos/farmacologia
17.
J Biochem Mol Toxicol ; 38(1): e23566, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37888945

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is an abnormal lipid accumulation disease in hepatocytes. The existing drugs for NAFLD have some side effects, so new therapeutic agents are required to be explored. In this study, the effect and mechanism of icariin (ICA) on high-fat diet-induced NAFLD were investigated. Firstly, a high-fat diet was used to construct a NAFLD rat model and HepG2 cells were treated with 1 mM free fatty acid (FFA). After ICA treatment, the serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBil), triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) were measured; liver injury and lipid deposition were observed by H&E and Oil Red O staining; interleukin-1ß (IL-1ß), IL-12, and IL-6 were measured by enzyme-linked immunosorbent assay. Additionally, qRT-PCR and western blot were performed to detect miR-206 expression and NF-κB/MAPK pathway-related protein expression in liver tissues and cells. After a variety of trials, we discovered that compared with the NAFLD group, ICA significantly reduced ALT, AST, TBil, TG, TC, and LDL-C levels and increased HDL-C levels, and improved liver tissue injury and lipid deposition. Moreover, ICA reduced IL-1ß, IL-12, and IL-6 levels in liver tissues and cells as well as inhibited MAPK and NF-κB-related protein expression in the liver tissues. Notably, ICA could significantly increase miR-206 expression in liver tissues and cells. Further experiments confirmed that inhibition of miR-206 was able to reverse the effect of ICA on NAFLD. In conclusion, ICA can alleviate NAFLD by upregulating miR-206 to mediate NF-κB and MAPK pathways.


Assuntos
Flavonoides , MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Ratos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/etiologia , NF-kappa B/metabolismo , LDL-Colesterol/metabolismo , LDL-Colesterol/farmacologia , LDL-Colesterol/uso terapêutico , Dieta Hiperlipídica/efeitos adversos , Interleucina-6/metabolismo , Fígado/metabolismo , Triglicerídeos , Bilirrubina/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Interleucina-12/metabolismo , Interleucina-12/farmacologia , Interleucina-12/uso terapêutico
18.
Pediatr Res ; 95(4): 1035-1040, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38040987

RESUMO

BACKGROUND: Spur-cell anemia sometimes accompanies cholestasis. We postulated that even in the absence of spur-cells, cholestasis might alter red blood cell (RBC) osmotic fragility and deformability. Therefore, we assessed these RBC measures by ektacytometry in pediatric patients. METHODS: We conducted a single center, prospective, cross-sectional investigation of RBC membrane characteristics by ektacytometry in pediatric patients with intra- and extrahepatic cholestasis followed at Cincinnati Children's Hospital Medical Center. We measured red cell membrane fragility and deformability in 17 patients with cholestasis and 17 age-matched controls without cholestasis. RESULTS: Patients with cholestasis had decreased RBC osmotic fragility compared to controls, with a significant left shift in Omin, indicating increased RBC surface-to-volume ratio. One showed spur cell morphology. However, the other 16 had no spurring, indicating that ektacytometry is a sensitive method to detect RBC membrane abnormalities. Left shift of Omin positively correlated with serum conjugated bilirubin levels and even more negatively with serum vitamin E concentration. CONCLUSIONS: This study suggests that subclinical red blood cell membrane abnormalities exist in most pediatric patients with cholestasis, increasing risk for hemolysis when subjected to oxidative stress. Hence minimizing pro-oxidants exposure and maximizing antioxidant exposure is advisable for this group. GOV IDENTIFIER: NCT05582447 https://clinicaltrials.gov/ct2/show/NCT05582447?cond=Cholestasis&cntry=US&state=US%3AOH&city=Cincinnati&draw=2&rank=2 . IMPACT: Spur cell anemia due to decreased red cell osmotic fragility and decreased deformability has been reported among patients with cholestasis. Ektacytometry is a reliable, reproducible method to measure red cell osmotic fragility and deformability. Few data describe red cell osmotic fragility or deformability in patients with cholestasis who may or may not have spur cell anemia. Ektacytometry shows that red cell osmotic fragility and deformability are decreased in many children with cholestasis even when spur cell anemia has not yet occurred. Factors associated with decreased osmotic fragility include elevated serum bilirubin, elevated serum bile acids, and decreased serum vitamin E.


Assuntos
Anemia , Colestase , Humanos , Criança , Estudos Prospectivos , Estudos Transversais , Eritrócitos , Colestase/diagnóstico , Colestase/metabolismo , Bilirrubina/metabolismo , Vitamina E/metabolismo
19.
Biol Pharm Bull ; 46(12): 1810-1819, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38044100

RESUMO

Yinzhihuang (YZH), a traditional Chinese medicine prescription, was widely used to treat cholestasis. Cholestatic liver injury limited the use of the immunosuppressive drug cyclosporine A (CsA) in preventing organ rejection after solid organ transplantation. Clinical evidences suggested that YZH could enhance bile acids and bilirubin clearance, providing a potential therapeutic strategy against CsA-induced cholestasis. Nevertheless, it remains unclear whether YZH can effectively alleviate CsA-induced cholestatic liver injury, as well as the molecular mechanisms responsible for its hepatoprotective effects. The purpose of the present study was to investigate the hepatoprotective effects of YZH on CsA-induced cholestatic liver injury and explore its molecular mechanisms in vivo and vitro. The results demonstrated that YZH significantly improved the CsA-induced cholestatic liver injury and reduced the level of liver function markers in serum of Sprague-Dawley (SD) rats. Targeted protein and gene analysis indicated that YZH increased bile acids and bilirubin efflux into bile through the regulation of multidrug resistance-associated protein 2 (Mrp2), bile salt export pump (Bsep), sodium taurocholate cotransporting polypeptide (Ntcp) and organic anion transporting polypeptide 2 (Oatp2) transport systems, as well as upstream nuclear receptors farnesoid X receptor (Fxr). Moreover, YZH modulated enzymes involved in bile acids synthesis and bilirubin metabolism including Cyp family 7 subfamily A member 1 (Cyp7a1) and uridine 5'-diphosphate (UDP) glucuronosyltransferase family 1 member A1 (Ugt1a1). Furthermore, the active components geniposidic acid, baicalin and chlorogenic acid exerted regulated metabolic enzymes and transporters in LO2 cells. In conclusion, YZH may prevent CsA-induced cholestasis by regulating the transport systems, metabolic enzymes, and upstream nuclear receptors Fxr to restore bile acid and bilirubin homeostasis. These findings highlight the potential of YZH as a therapeutic intervention for CsA-induced cholestasis and open avenues for further research into its clinical applications.


Assuntos
Colestase , Ciclosporina , Ratos , Animais , Ciclosporina/efeitos adversos , Ratos Sprague-Dawley , Fígado/metabolismo , Colestase/induzido quimicamente , Colestase/tratamento farmacológico , Colestase/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Ácidos e Sais Biliares/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Bilirrubina/metabolismo
20.
BMC Microbiol ; 23(1): 357, 2023 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-37980506

RESUMO

BACKGROUND: Infantile cholestasis (IC) is the most common hepatobiliary disease in infants, resulting in elevated direct bilirubin levels. Indeed, hepatointestinal circulation impacts bile acid and bilirubin metabolism. This study evaluates changes in the gut microbiota composition in children with IC and identifies abnormal metabolite profiles associated with microbial alterations. RESULTS: The gut microbiota in the IC group exhibits the higher abundance of Veillonella, Streptococcus and Clostridium spp. (P < 0.05), compared to healthy infants (CON) group. Moreover, the abundance of Ruminococcus, Vibrio butyricum, Eubacterium coprostanogenes group, Intestinibacter, and Faecalibacterium were lower (P < 0.05). In terms of microbiota-derived metabolites, the levels of fatty acids (palmitoleic, α-linolenic, arachidonic, and linoleic) (P < 0.05) increased and the levels of amino acids decreased in IC group. Furthermore, the abundances of Ruminococcus, Eubacterium coprostanoligenes group, Intestinibacter and Butyrivibrio are positively correlated with proline, asparagine and aspartic acid, but negatively correlated with the α-linolenic acid, linoleic acid, palmitoleic acid and arachidonic acid. For analysis of the relationship between the microbiota and clinical index, it was found that the abundance of Veillonella and Streptococcus was positively correlated with serum bile acid content (P < 0.05), while APTT, PT and INR were negatively correlated with Faecalibalum and Ruminococcus (P < 0.05). CONCLUSION: Microbiota dysbiosis happened in IC children, which also can lead to the abnormal metabolism, thus obstructing the absorption of enteral nutrition and aggravating liver cell damage. Veillonella, Ruminococcus and Butyrivibrio may be important microbiome related with IC and need further research.


Assuntos
Colestase , Microbioma Gastrointestinal , Lactente , Criança , Humanos , Colestase/metabolismo , Fígado/metabolismo , Streptococcus , Bilirrubina/metabolismo , Ácidos e Sais Biliares/metabolismo
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