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1.
ACS Biomater Sci Eng ; 10(3): 1494-1506, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38414275

RESUMO

The use of hemoperfusion adsorbents for the removal of bilirubin in patients with liver failure has become a critical treatment. However, the insufficient clearance of bilirubin and the possibility of bacterial infection during hemoperfusion limit the application. In this work, we designed a novel antibacterial bilirubin adsorbent (PSVT) through the suspension polymerization reaction between double-bond functionalized TiO2 nanoparticles and styrene. PSVT showed an excellent bilirubin adsorption ability and antibacterial performance, ensuring efficient clearance of bilirubin in liver failure patients during hemoperfusion and preventing bacterial infection. The experimental results indicated that TiO2 was uniformly dispersed in the microspheres, which improved the mesoporous structure and increased the specific surface area. Composite adsorbent PSVT showed an exceptional bilirubin adsorption capacity, with the maximum adsorption capacity reaching 24.3 mg/g. In addition, the introduction of TiO2 endowed PSVT with excellent antibacterial ability; the ultimate antibacterial rates against Escherichia coli and Staphylococcus aureus reached 97.31 and 96.47%, respectively. In summary, PSVT served as a novel antibacterial bilirubin adsorbent with excellent bilirubin clearance capacity and antibacterial performance, providing excellent application prospects for treating liver failure patients.


Assuntos
Infecções Bacterianas , Hemoperfusão , Falência Hepática , Nanocompostos , Humanos , Bilirrubina/química , Poliestirenos/química , Hemoperfusão/métodos , Nanocompostos/uso terapêutico
2.
J Biophotonics ; 16(7): e202200316, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36995028

RESUMO

The onset of intracerebral hemorrhage and its progression toward acute brain injury have been correlated with the concentration of unconjugated bilirubin (BR). In addition, BR has been considered a novel predictor of outcome from intracranial hemorrhage. Since the existing invasive approach for determining localized BR and biliverdin (BV) concentration within the hemorrhagic brain lesion is not feasible, the predictive capability of BR in terms of determining the onset of hemorrhage and understanding the consequences of its progression (age) is unknown. In this study, we have demonstrated a photoacoustic (PA) approach to the noninvasive measurement of BR-BV ratio that can be utilized longitudinally to approximate the onset of the hemorrhage. The PA imaging-based measurements of BV and BR in tissues and fluids can potentially be used to determine hemorrhage "age," quantitatively evaluate the hemorrhage resorption or detect a rebleeding, and assess responses to therapy and prognosis.


Assuntos
Bilirrubina , Biliverdina , Humanos , Biliverdina/química , Bilirrubina/química , Análise Espectral , Hemorragia/diagnóstico por imagem
3.
Int J Biol Macromol ; 235: 123868, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36870639

RESUMO

Metal-organic frameworks (MOFs) have a potential application in blood purification, but their microcrystalline nature has hampered their industrial application. Here, novel MOFs-polymer beads based on UiO, sodium alginate, polyacrylic acid, and poly (ethylene imine) were prepared and applied as a whole blood hemoadsorbent for the first time. The amidation among polymers immobilized UiO66-NH2 into the network of the optimal product (SAP-3), and the NH2 of UiO66-NH2 significantly increased the removal rate (70 % within 5 min) of SAP-3 on bilirubin. The adsorption of SAP-3 on bilirubin mainly obeyed the pseudo-second-order kinetic, Langmuir isotherm and Thomas models with a maximum adsorption capacity (qm) of 63.97 mg·g-1. Experimental and density functional theory simulation results show that bilirubin was mainly adsorbed by UiO66-NH2via electrostatic force, hydrogen bonding, and π-π interactions. Notably, the adsorption in vivo show that the total bilirubin removal rate in the whole blood of the rabbit model was up to 42 % after 1 h of adsorption. Given its excellent stability, cytotoxicity, and hemocompatibility, SAP-3 has a great potential in hemoperfusion therapy. This study proposes an effective strategy for settling the powder property of MOFs and could provide experimental and theoretical references for application of MOFs in blood purification.


Assuntos
Estruturas Metalorgânicas , Poluentes Químicos da Água , Animais , Coelhos , Bilirrubina/química , Heparina , Polímeros/química , Adsorção , Etilenos , Poluentes Químicos da Água/química
4.
Anticancer Res ; 43(3): 1317-1323, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36854508

RESUMO

BACKGROUND/AIM: Lenvatinib is a multiple-tyrosine kinase inhibitor used to treat hepatocellular carcinoma (HCC), and its systematic concentration varies according to liver function. The albumin-bilirubin (ALBI) grade is a novel indicator for predicting liver function in patients with hepatic disease. This study aimed to investigate the relationship between ALBI grade and HCC patients' lenvatinib treatment duration. PATIENTS AND METHODS: This is a retrospective cohort study of patients with HCC and Child-Pugh A treated with lenvatinib between April 2018 and December 2019. The baseline liver function was determined using the ALBI grade. The primary outcome was discontinuation owing to adverse events. The risk factors for discontinuation owing to adverse effects were analyzed using logistic regression. RESULTS: This investigation included 48 HCC patients. Patients with ALBI grade 2 had a significantly shorter time of discontinuation due to adverse events than those with grade 1 (p=0.036). However, the time of treatment failure did not differ between the groups. Multiple logistic regression analysis showed that ALBI grade 2 and non-use of antihypertensive drugs were independent factors for discontinuation due to adverse events [odds ratio (OR)=14.1, 95% confidence interval (CI)=1.46-135, p=0.022 and OR=5.48, 95% CI=1.13-23.9, p=0.024, respectively]. CONCLUSION: The ALBI grades may be useful in predicting adverse events caused by lenvatinib in patients with HCC and Child-Pugh A.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Albuminas/química , Bilirrubina/química , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Estudos Retrospectivos , Compostos de Fenilureia/efeitos adversos , Quinolinas/efeitos adversos
5.
J Org Chem ; 87(5): 3089-3103, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-35130431

RESUMO

Bilirubin (BR) is an essential metabolite formed by the catabolism of heme. Phototherapy with blue-green light can be applied to reduce high concentrations of BR in blood and is used especially in the neonatal period. In this work, we studied the photochemistry of (Z)-isovinylneoxanthobilirubic acid methyl ester, a dipyrrinone subunit of BR, by steady-state absorption, femtosecond transient absorption, and stimulated Raman spectroscopies. Both the (Z)- and (E)-configurational isomers of isovinylneoxanthobilirubic acid undergo wavelength-dependent and reversible photoisomerization. The isomerization from the excited singlet state is ultrafast (the lifetimes of (Z)- and (E)-isomers were found to be ∼0.9 and 0.1 ps, respectively), and its efficiencies increase with increased photon energy. In addition, we studied sensitized photooxidation of the dipyrrinone subunit by singlet oxygen that leads to the formation of propentdyopents. Biological activities of these compounds, namely, effects on the superoxide production, lipoperoxidation, and tricarboxylic acid cycle metabolism, were also studied. Finally, different photochemical and biological properties of this BR subunit and its structural analogue, (Z)-vinylneoxanthobilirubic acid methyl ester, studied before, are discussed.


Assuntos
Bilirrubina , Ésteres , Bilirrubina/química , Humanos , Recém-Nascido , Fotoquímica , Fototerapia/métodos , Análise Espectral Raman
6.
J Enzyme Inhib Med Chem ; 37(1): 487-501, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34986721

RESUMO

Bilirubin (BR) is the final product of haem catabolism. Disruptions along BR metabolic/transport pathways resulting from inherited disorders can increase plasma BR concentration (hyperbilirubinaemia). Unconjugated hyperbilirubinemia may induce BR accumulation in brain, potentially causing irreversible neurological damage, a condition known as BR encephalopathy or kernicterus, to which newborns are especially vulnerable. Numerous pharmaceutical strategies, mostly based on hemoperfusion, have been proposed over the last decades to identify new valid, low-risk alternatives for BR removal from plasma. On the other hand, accumulating evidence indicates that BR produces health benefits due to its potent antioxidant, anti-inflammatory and immunomodulatory action with a significant potential for the treatment of a multitude of diseases. The present manuscript reviews both such aspects of BR pharmacology, gathering literature data on applied pharmaceutical strategies adopted to: (i) reduce the plasma BR concentration for preventing neurotoxicity; (ii) produce a therapeutic effect based on BR efficacy in the treatment of many disorders.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Bilirrubina/farmacologia , Doenças Neuroinflamatórias/tratamento farmacológico , Anti-Inflamatórios/sangue , Anti-Inflamatórios/química , Antioxidantes/química , Bilirrubina/sangue , Bilirrubina/química , Humanos
7.
Prep Biochem Biotechnol ; 52(4): 365-374, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34319856

RESUMO

The UnaG protein is a ligand (unconjugated bilirubin) dependent fluorescence protein isolated from Unagi freshwater eel larvae and expressed as fusion in heterologous expression systems. Bilirubin is a tetrapyrrole molecule mainly produced from heme catabolism by the destruction of erythrocytes in the body. Bilirubin can cause kernicterus, a serious condition associated with permanent neurological damage in neonates with the passage of brain tissue. Different methods have been developed for plasma bilirubin analysis and quantification. The use of UnaG fluorescence protein triggered by bilirubin has become a new approach in bilirubin studies. In this study, we aimed to investigate the biophysical characterization of ligand interactions with the proteins obtained as a result of mutations (UnaGY99F_Y134W, UnaGN57E, UnaGL41F, and UnaGF17M) on the amino acid sequence of TolAIII-UnaG protein. After the purity levels of the expressed proteins have been analyzed by SDS-PAGE, secondary structures and thermal melting temperatures of the proteins have been examined by circular dichroism spectroscopy. Then determination of excitation and emission points by fluorescence spectroscopy, titration studies have been performed with bilirubin, and dissociation constant was calculated. According to the biophysical characterization studies, UnaGL41F has the highest affinity and stability among the mutants.


Assuntos
Bilirrubina , Sequência de Aminoácidos , Bilirrubina/análise , Bilirrubina/química , Bilirrubina/metabolismo , Humanos , Recém-Nascido , Ligantes , Mutação , Espectrometria de Fluorescência
8.
Bioorg Med Chem Lett ; 51: 128361, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34543755

RESUMO

As a unique ligand gated ion channel in the P2-receptor family, P2X7R is highly expressed in various tumors. The activated P2X7R facilitates tumor growth and metastasis. Hypoxia, inflammation and necrosis in the tumor microenvironment (TME) cause a large amount of adenosine triphosphate (ATP) accumulated in the TME. High concentration of ATP can abnormally activate P2X7R, which induces pore formation and further facilitates the Ca2+ ion influx and non-specific substance intake. Therefore, inhibition of P2X7R activation can be applied as a potential anti-tumor therapy strategy. However, there is currently no FDA approved drugs for this target for anti-tumor treatment. In this study, we identified bilirubin as novel P2X7R antagonist by using structure based virtual screening combined with cell based assays. Molecular docking studies indicated that bilirubin probably interacted with P2X7R by forming hydrogen-π interactions with residues V173, E174 and K311. The compound bilirubin inhibited the P2X7R gated EB intake by cancer cells. Meanwhile, bilirubin was capable to inhibit the cell proliferation and migration of P2X7R expressed HT29 cells. The phosphorylation of mTOR, STAT3 and GSK3ß were significantly decreased when bilirubin was present. Finally, in vivo experiment exhibited the anti-tumor effect of bilirubin in the MC38 bearing mice model, but did not show tissue damage in different organs. In conclusion, bilirubin was identified as a novel P2X7R antagonist and it may have potential for anti-cancer treatment, although various functions of the molecule should be considered.


Assuntos
Antineoplásicos/farmacologia , Bilirrubina/farmacologia , Descoberta de Drogas , Antagonistas do Receptor Purinérgico P2X/farmacologia , Receptores Purinérgicos P2X7/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Bilirrubina/síntese química , Bilirrubina/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Antagonistas do Receptor Purinérgico P2X/síntese química , Antagonistas do Receptor Purinérgico P2X/química , Relação Estrutura-Atividade
9.
Pharm Biol ; 59(1): 1139-1149, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34425063

RESUMO

CONTEXT: Chronic non-healing diabetic wound therapy is an important clinical challenge. Manipulating the release of bioactive factors from an adhesive hydrogel is an effective approach to repair chronic wounds. As an endogenous antioxidant, bilirubin (BR) has been shown to promote wound healing. Nonetheless, its application is limited by its low water solubility and oxidative degradation. OBJECTIVE: This study developed a bilirubin-based formulation for diabetic wound healing. MATERIALS AND METHODS: Bilirubin was incorporated into ß-CD-based inclusion complex (BR/ß-CD) which was then loaded into a bioadhesive hydrogel matrix (BR/ß-CD/SGP). Scratch wound assays were performed to examine the in vitro pro-healing activity of BR/ß-CD/SGP (25 µg/mL of BR). Wounds of diabetic or non-diabetic rats were covered with BR or BR/ß-CD/SGP hydrogels (1 mg/mL of BR) and changed every day for a period of 7 or 21 days. Histological assays were conducted to evaluate the in vivo effect of BR/ß-CD/SGP. RESULTS: Compared to untreated (18.7%) and BR (55.2%) groups, wound closure was more pronounced (65.0%) in BR/ß-CD/SGP group. In diabetic rats, the wound length in BR/ß-CD/SGP group was smaller throughout the experimental period than untreated groups. Moreover, BR/ß-CD/SGP decreased TNF-α levels to 7.7% on day 3, and elevated collagen deposition and VEGF expression to 11.9- and 8.2-fold on day 14. The therapeutic effects of BR/ß-CD/SGP were much better than those of the BR group. Similar observations were made in the non-diabetic model. DISCUSSION AND CONCLUSION: BR/ß-CD/SGP promotes wound healing and tissue remodelling in both diabetic and non-diabetic rats, indicating an ideal wound-dressing agent.


Assuntos
Bilirrubina/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Cicatrização/efeitos dos fármacos , beta-Ciclodextrinas/química , Adesivos , Animais , Antioxidantes/administração & dosagem , Antioxidantes/química , Antioxidantes/farmacologia , Bilirrubina/administração & dosagem , Bilirrubina/química , Colágeno/metabolismo , Diabetes Mellitus Experimental/complicações , Células Endoteliais da Veia Umbilical Humana , Humanos , Hidrogéis , Ratos , Solubilidade , Fatores de Tempo , Ferimentos e Lesões/tratamento farmacológico , Ferimentos e Lesões/etiologia
10.
J Mater Chem B ; 9(28): 5628-5635, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34109969

RESUMO

Hemoperfusion has become the third-generation treatment strategy for patients suffering from hyperbilirubinemia, but adsorbents used for bilirubin removal mostly face intractable problems, such as unsatisfactory adsorption performance and poor hemocompatibility. Metal-organic frameworks (MOFs) are promising adsorbents for hemoperfusion due to their high specific surface areas and easily modified organic ligands. However, their microporous properties and separation have hampered their application. Here, a novel hierarchical core-shell nanoplatform (named Double-PEG) with tailored binding sites and pore sizes based on Fe3O4@C and Uio66-NH2 was constructed. Notably, Double-PEG showed excellent bilirubin uptake of up to 1738.30 mg g-1 and maintained excellent bilirubin removal efficiency in simulated biological solutions. A study on the adsorption mechanism showed that the adsorption of Double-PEG towards bilirubin tended to be chemical adsorption and in accordance with the Langmuir model. Besides, the good separability, recyclability, cytotoxicity and hemocompatibility of Double-PEG show great potential in hemoperfusion therapy. The finding of this study may provide a novel insight into the application of MOF materials in the field of hemoperfusion.


Assuntos
Bilirrubina/isolamento & purificação , Materiais Biocompatíveis/química , Carbono/química , Óxido Ferroso-Férrico/química , Estruturas Metalorgânicas/química , Nanopartículas/química , Adsorção , Bilirrubina/química , Materiais Biocompatíveis/síntese química , Linhagem Celular , Humanos , Cinética , Estruturas Metalorgânicas/síntese química , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície , Purificação da Água
11.
Chem Asian J ; 16(14): 1949-1955, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34041869

RESUMO

We discovered that the 2D Ti3 C2 Tx MXene sheet displays an ultra-high removal capability for bilirubin (BR). In particular, MXene shows 47.6 times higher removal efficiency over traditional activated carbon absorbents. The effect of MXene on the removal rate of BR in BR solution containing different concentrations of bovine serum albumin (BSA) was studied. The adsorption capacity of BSA for BR at high concentration of 5 g L-1 was about 85% of the best adsorption capacity. The MXene before and after adsorption was characterized by SEM, FT-IR and XPS. Furthermore, MXene beads were prepared, and the hemoperfusion simulation experiment was carried out. The results show that the adsorption capacity of MXene for bilirubin can reach 1192.9 mg g-1 . This study suggests that MXene may be promising in the treatment of hyperbilirubinemia.


Assuntos
Bilirrubina/química , Cerâmica/química , Adsorção , Animais , Carbono/química , Bovinos , Soroalbumina Bovina/química , Titânio/química
12.
Sci Rep ; 11(1): 10190, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33986443

RESUMO

There are different methods of artificial liver support for patients with acute liver dysfunction (ALD). However, CytoSorb (CS) might be a new approved option for those patients. Question of interest is whether the elimination performance of CS was comparable to that of advanced organ support (ADVOS). Patients, treated with CS (integrated into high-flux dialysis) or ADVOS and a total bilirubin > 10 mg/dl were included. Laboratory parameters were evaluated before starting therapy (d0) and 12-24 h thereafter (d1). The Wilcoxon-test with associated samples was used for statistical analysis. Thirty-nine patients (33 CS, 6 ADVOS) were included. The median bilirubin at d0 was 16.9 and 17.7 mg/dl and at d1 was 13.2 and 15.9 mg/dl, in the CS and ADVOS group, respectively. There was a significant bilirubin reduction as well in the CS group (p < 0.001, median relative reduction: 22.5%) as in the ADVOS group (p = 0.028, median relative reduction: 22.8%). There was no significant difference in the relative bilirubin reduction between CS and ADVOS therapies. The use of CytoSorb and ADVOS in patients with ALD led to a significant and comparable decrease in total bilirubin. The easy use of CS might be an advantage compared to other procedures.


Assuntos
Bilirrubina/isolamento & purificação , Hepatopatias/terapia , Diálise Renal/métodos , Adsorção , Adulto , Idoso , Idoso de 80 Anos ou mais , Albuminas/metabolismo , Bilirrubina/química , Estado Terminal , Citocinas/sangue , Citocinas/metabolismo , Feminino , Alemanha , Humanos , Hepatopatias/metabolismo , Hepatopatias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Retrospectivos , Albumina Sérica/metabolismo
13.
Mol Pharm ; 18(5): 2053-2065, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33886324

RESUMO

We fabricated bilirubin-bovine serum albumin (BR-BSA) nanocomplexes as candidates for the delivery of 5-fluoro-2-deoxyuridine (5FUdr) against experimental murine lymphoma. BR was attached to 5FUdr via acid-labile ester bonds mimicking small-molecule drug conjugates. The construct was self-assembled with BSA through strong noncovalent interactions with high drug occupancy in the core and labeled with folic acid (FA) to target cancer cells. The BR-5FUdr-BSA-FA nanoconstruct exhibits excellent biocompatibility, prevents nephrotoxicity, and is tolerated by red blood cells and mononuclear cells. The construct also showed increased accumulation in lymph nodes and tumor cells. BR-5FUdr-BSA-FA caused prolonged growth inhibition and apoptosis, enhanced mitochondrial reactive oxygen species generation, and minimized the viability of parental and doxorubicin-resistant Dalton's lymphoma cells. Treatment of tumor-bearing mice with BR-5FUdr-BSA-FA significantly increased the life span of the animals, improved their histopathological parameters, and downregulated PD-1 expression, suggesting the potential of the construct for 5FUdr delivery to treat lymphoma.


Assuntos
Desoxiuridina/análogos & derivados , Portadores de Fármacos/química , Linfoma/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Bilirrubina/química , Materiais Biomiméticos/química , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Desoxiuridina/administração & dosagem , Desoxiuridina/farmacocinética , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Linfoma/patologia , Camundongos , Receptor de Morte Celular Programada 1/metabolismo , Soroalbumina Bovina/química
14.
Ann Clin Biochem ; 58(4): 311-317, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33588585

RESUMO

BACKGROUND: Direct-reacting bilirubin concentrations measured using vanadate chemical oxidation method do not exactly match the conjugated bilirubin concentration. One of the causes is the effect of bilirubin photoisomers. However, the quantitative evaluation of the effects of these photoisomers has not been sufficiently conducted. In particular, the influence of bilirubin configurational isomers on direct bilirubin is the most critical factor. METHODS: Sixteen residual serum samples were used. For quantitative analysis based on the change in direct bilirubin and bilirubin configurational isomer, samples were irradiated via blue light-emitting diodes to suppress the production of bilirubin structural isomers. Total bilirubin and direct bilirubin concentrations were measured using the vanadate chemical oxidation method. Concentrations of 4Z,15Z-bilirubin IXα and its photoisomers were measured using high-performance liquid chromatography. The sum of 4Z,15E-bilirubin IXα and 4E,15Z-bilirubin IXα was notated as bilirubin configurational isomer, and the differences between the measured values of the irradiated and non-irradiated samples were calculated and notated as ΔDB and ΔBCI. RESULTS: In non-irradiated and irradiated samples, total bilirubin and direct bilirubin concentrations were 10.73 mg/dL with significant a decrease to 10.60 mg/dL and 0.69 mg/dL with a significant increase to 0.78 mg/dL, while bilirubin configurational isomer values were 1.00 mg/dL and 1.52 mg/dL, respectively. The linear regression equation revealed a significant positive correlation of Y = 0.187X-0.006 between ΔDB (Y) and ΔBCI (X). CONCLUSION: Applying the vanadate chemical oxidation method affected approximately 19% of the bilirubin configurational isomer concentration for direct bilirubin. Extreme caution is necessary when interpreting the measured values of samples indicative of unconjugated hyperbilirubinaemia.


Assuntos
Bilirrubina/análise , Bilirrubina/química , Fotoquímica/métodos , Técnicas de Química Analítica , Humanos , Hiperbilirrubinemia/sangue , Recém-Nascido , Modelos Lineares , Triagem Neonatal , Oxigênio/química , Estereoisomerismo , Vanadatos/análise
15.
J Photochem Photobiol B ; 215: 112121, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33422899

RESUMO

The bichromophore nature of bilirubin explains the presence of at least two partially overlaying bands in both absorption and fluorescence emission spectra, and accounts for interchromophore exciton transfer events responsible for the emission sensitivity to the molecular environment and excitation wavelength. These concepts were likely responsible for the previously reported good yield of the unexpected remarkable bilirubin fluorescence emission under excitation at 366 nm, at which bilirubin absorption is very low. In this connection, aim of this work is to further investigate bilirubin spectral excitation properties and their diagnostic potential, until now poorly considered. Fluorescence excitation spectra of pure bilirubin in solution with solubilizing agents observed at 520 and 570 nm showed a wide region in the 430-510 nm range, similar to the absorption profile. In addition, an excitation band centered at about 400 nm was detected. Comparable excitation features were detected in rat serum. The 430-510 nm excitation region was well separated from a main band at shorter wavelength, ascribable to other endogenous fluorophores, with a shoulder at about 400 nm which was also easily discriminated by spectral fitting analysis. The bands ascribable to bilirubin showed changes of their relative contribution to the overall spectral region after liver ischemia/reperfusion, comparable to bilirubin biochemical data. Excitation spectra proved to discriminate the fluorescence of serum bilirubin at levels much lower than emission spectra, opening promising perspectives to improve the real time fluorescence analysis of crude serum in the absence of any exogenous labelling agent, and advance the diagnostic application of optical-biopsy in experimental hepatology and biomedicine.


Assuntos
Bilirrubina/sangue , Bilirrubina/química , Fluorescência , Animais , Ratos , Soluções , Espectrometria de Fluorescência
16.
Int J Biol Macromol ; 166: 179-189, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33172613

RESUMO

In this study, bacterial cellulose (BC)/soy protein isolate (SPI) composite membranes were prepared by in situ cross-linked polymerization, and used as efficient blood compatible adsorbents to remove bilirubin. The obtained composite membranes were successively characterized by FTIR, SEM, AFM, contact angle test and hemolysis assay, which exhibited unique protein coated 3D fibrous network structures, hydrophobic surfaces and outstanding blood compatibility due to the incorporation of SPI. The BC/SPI membranes with high SPI content showed high adsorption efficiency, short adsorption equilibrium time (2 h) and multiple adsorption effects on bilirubin. The adsorption rate for free bilirubin of BC/SPI5 membrane could reach 78.8% when the bilirubin concentration was 100 mg L-1, while it increased to over 96.5% when the initial bilirubin concentration exceeded 400 mg L-1. More importantly, the BC/SPI5 membrane still exhibited high adsorption rate (over 70%) in presence of albumin. Furthermore, the composite membrane could also maintain high dynamic adsorption efficiency in self-made hemoperfusion devices. This novel naturally-derived membrane is an economical and efficient absorbent for the remove of bilirubin, and will provide new ideas for therapy of hemoperfusion without plasma separation process.


Assuntos
Bilirrubina/química , Celulose/análogos & derivados , Membranas Artificiais , Proteínas de Soja/química , Adsorção , Bilirrubina/sangue , Hemólise , Hemoperfusão/métodos , Humanos
17.
Pediatr Res ; 89(3): 510-517, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32357361

RESUMO

BACKGROUND: Unconjugated hyperbilirubinemia, a feature of neonatal jaundice or Crigler-Najjar syndrome, can lead to neurotoxicity and even death. We previously demonstrated that unconjugated bilirubin (UCB) can be eliminated via transintestinal excretion in Gunn rats, a model of unconjugated hyperbilirubinemia, and that this is stimulated by enhancing fecal fatty acid excretion. Since transintestinal excretion also occurs for cholesterol (TICE), we hypothesized that increasing fecal cholesterol excretion and/or TICE could also enhance fecal UCB disposal and subsequently lower plasma UCB concentrations. METHODS: To determine whether increasing fecal cholesterol excretion could ameliorate unconjugated hyperbilirubinemia, we treated hyperbilirubinemic Gunn rats with ezetimibe (EZE), an intestinal cholesterol absorption inhibitor, and/or a liver X receptor (LXR) and farnesoid X receptor (FXR) agonist (T0901317 (T09) and obeticholic acid (OCA), respectively), known to stimulate TICE. RESULTS: We found that EZE treatment alone or in combination with T09 or OCA increased fecal cholesterol disposal but did not lower plasma UCB levels. CONCLUSIONS: These findings do not support a link between the regulation of transintestinal excretion of cholesterol and bilirubin. Furthermore, induction of fecal cholesterol excretion is not a potential therapy for unconjugated hyperbilirubinemia. IMPACT: Increasing fecal cholesterol excretion is not effective to treat unconjugated hyperbilirubinemia. This is the first time a potential relation between transintestinal excretion of cholesterol and unconjugated bilirubin is investigated. Transintestinal excretion of cholesterol and unconjugated bilirubin do not seem to be quantitatively linked. Unlike intestinal fatty acids, cholesterol cannot "capture" unconjugated bilirubin to increase its excretion. These results add to our understanding of ways to improve and factors regulating unconjugated bilirubin disposal in hyperbilirubinemic conditions.


Assuntos
Ácido Quenodesoxicólico/análogos & derivados , Colesterol/metabolismo , Síndrome de Crigler-Najjar/terapia , Ezetimiba/uso terapêutico , Fezes/química , Hidrocarbonetos Fluorados/uso terapêutico , Hiperbilirrubinemia/terapia , Sulfonamidas/uso terapêutico , Animais , Bile/química , Ácidos e Sais Biliares/metabolismo , Bilirrubina/química , Ácido Quenodesoxicólico/farmacologia , Ácido Quenodesoxicólico/uso terapêutico , Síndrome de Crigler-Najjar/metabolismo , Gorduras na Dieta/farmacocinética , Ezetimiba/farmacologia , Haptoglobinas/análise , Hidrocarbonetos Fluorados/farmacologia , Intestinos/efeitos dos fármacos , Intestinos/metabolismo , Lipídeos/sangue , Receptores X do Fígado/metabolismo , Masculino , PPAR delta/metabolismo , Distribuição Aleatória , Ratos , Ratos Gunn , Receptores Citoplasmáticos e Nucleares/metabolismo , Sulfonamidas/farmacologia
18.
J Phys Chem A ; 124(50): 10457-10471, 2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33283519

RESUMO

The photochemistry of bilirubin has been extensively studied due to its importance in the phototherapy of hyperbilirubinemia. In the present work, we investigated the ultrafast photodynamics of a bilirubin dipyrrinone subunit, vinylneoxanthobilirubic acid methyl ester. The photoisomerization and photocyclization reactions of its (E) and (Z) isomers were studied using femtosecond transient absorption spectroscopy and by multireference electronic structure theory, where the nonadiabatic dynamics was modeled with a Landau-Zener surface hopping technique. The following picture has emerged from the combined theoretical and experimental approach. Upon excitation, dipyrrinone undergoes a very fast vibrational relaxation, followed by an internal conversion on a picosecond time scale. The internal conversion leads either to photoisomerization or regeneration of the starting material. Further relaxation dynamics on the order of tens of picoseconds was observed in the ground state. The nonadiabatic simulations revealed a strong conformational control of the photodynamics. The ultrafast formation of a cyclic photochemical product from a less-populated conformer of the studied subunit was predicted by our calculations. We discuss the relevance of the present finding for the photochemistry of native bilirubin. The work has also pointed to the limits of semiclassical nonadiabatic simulations for simulating longer photochemical processes, probably due to the zero-point leakage issue.


Assuntos
Bilirrubina/química , Processos Fotoquímicos , Análise Espectral/métodos , Termodinâmica , Modelos Moleculares , Conformação Molecular , Teoria Quântica
19.
Pak J Biol Sci ; 23(9): 1162-1175, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32981247

RESUMO

BACKGROUND AND OBJECTIVE: There is a widespread use of medicinal herbs with beneficial uses against different diseased conditions. This study was carried out to identify and study the biological effect of Acacia gerrardii leaf extract on lowering blood sugar in rats suffering from diabetic nephropathy. MATERIALS AND METHODS: It studied the effects of leaf extract at concentrations ranging from 100-500 mg kg-1 b.wt. per day for 4 weeks. Serum glucose levels, total lipids profile and kidney functions were estimated. Plasma levels of sodium and potassium as well as total bilirubin levels were assessed and kidneys from different groups were histopathologically examined. RESULTS: The results showed that leaves were rich in the major compounds of phenolic acids, including salicylic acid and flavonoids with reduction of total lipids, triglycerides and total cholesterol in diabetic rats with renal failure together with reduction in uric acid, creatinine and urea with reduced vacuolar degeneration of tubules and basement membrane thickening. Additionally, the phylogenetic analysis using ISSR primers detected a genetic divergence among different samples. The results showed that the rich antioxidant content of Acacia gerrardii improved lipid, serum antioxidant and kidney function profiles in diabetic rats. CONCLUSION: Acacia gerrardii could be used as a safe source of antioxidants. Moreover, the ISSR assay proved its usefulness in detecting genetic variations among different Acacia gerrardii samples.


Assuntos
Acacia/efeitos dos fármacos , Impressões Digitais de DNA , Nefropatias Diabéticas/genética , Metanol/química , Animais , Antioxidantes/metabolismo , Bilirrubina/química , Glicemia/análise , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Variação Genética , Hidroxibenzoatos/química , Hipoglicemiantes/farmacologia , Rim/metabolismo , Lipídeos/química , Masculino , Folhas de Planta/metabolismo , Ratos , Salicilatos/química , Triglicerídeos/química
20.
Sci Rep ; 10(1): 11264, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32647200

RESUMO

To date, only two pigments have been identified in avian eggshells: rusty-brown protoporphyrin IX and blue-green biliverdin IXα. Most avian eggshell colours can be produced by a mixture of these two tetrapyrrolic pigments. However, tinamou (Tinamidae) eggshells display colours not easily rationalised by combination of these two pigments alone, suggesting the presence of other pigments. Here, through extraction, derivatization, spectroscopy, chromatography, and mass spectrometry, we identify two novel eggshell pigments: yellow-brown tetrapyrrolic bilirubin from the guacamole-green eggshells of Eudromia elegans, and red-orange tripyrrolic uroerythrin from the purplish-brown eggshells of Nothura maculosa. Both pigments are known porphyrin catabolites and are found in the eggshells in conjunction with biliverdin IXα. A colour mixing model using the new pigments and biliverdin reproduces the respective eggshell colours. These discoveries expand our understanding of how eggshell colour diversity is achieved. We suggest that the ability of these pigments to photo-degrade may have an adaptive value for the tinamous.


Assuntos
Bilirrubina/química , Biliverdina/química , Casca de Ovo/química , Pigmentação , Pigmentos Biológicos/química , Porfirinas/química , Pirróis/química , Animais , Aves , Cromatografia Líquida de Alta Pressão , Cor , Espectrofotometria Ultravioleta , Espectrometria de Massas em Tandem
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