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1.
Sci Rep ; 14(1): 15232, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956281

RESUMO

Intravenous immunoglobulin (IVIG) resistance in Kawasaki disease (KD) was associated with coronary artery lesions. Neutrophil percentage-to-albumin ratio (NPAR) is an index of mortality in several inflammatory diseases. This study focused on the association of NPAR with IVIG- resistance in KD. Clinical and laboratory data of 438 children with KD before IVIG treatment were retrospectively analyzed. Notably, high NPAR was associated with older age, high WBC, NP, ALT, total bilirubin and CRP, as well as with high the incidence of IVIG-resistance, and with low hemoglobin (Hb), PLT, ALB and sodium levels. NPAR (OR: 2.366, 95% CI: 1.46-3.897, p = 0.001) and Hb (OR: 0.967, 95% CI: 0.944-0.989, p = 0.004) were independent risk factors for IVIG-resistance. NPAR showed linear relation with IVIG-resistance (p for nonlinear = 0.711) and the nonlinear correlation was found between IVIG-resistance and Hb (p for nonlinear = 0.002). The predictive performance of NPAR was superior to Beijing model (z = 2.193, p = 0.028), and not inferior to Chongqing model (z = 0.983, p = 0.326) and the combination of NPAR and Hb (z = 1.912, p = 0.056). These findings revealed that NPAR is a reliable predictor of IVIG-resistance.


Assuntos
Biomarcadores , Resistência a Medicamentos , Imunoglobulinas Intravenosas , Síndrome de Linfonodos Mucocutâneos , Neutrófilos , Humanos , Síndrome de Linfonodos Mucocutâneos/sangue , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Imunoglobulinas Intravenosas/uso terapêutico , Masculino , Feminino , Pré-Escolar , Lactente , Biomarcadores/sangue , Estudos Retrospectivos , Criança , Albuminas/metabolismo
2.
Cell Rep Med ; 5(7): 101619, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38897206

RESUMO

Liver-directed adeno-associated viral (AAV) vector-mediated homology-independent targeted integration (AAV-HITI) by CRISPR-Cas9 at the highly transcribed albumin locus is under investigation to provide sustained transgene expression following neonatal treatment. We show that targeting the 3' end of the albumin locus results in productive integration in about 15% of mouse hepatocytes achieving therapeutic levels of systemic proteins in two mouse models of inherited diseases. We demonstrate that full-length HITI donor DNA is preferentially integrated upon nuclease cleavage and that, despite partial AAV genome integrations in the target locus, no gross chromosomal rearrangements or insertions/deletions at off-target sites are found. In line with this, no evidence of hepatocellular carcinoma is observed within the 1-year follow-up. Finally, AAV-HITI is effective at vector doses considered safe if directly translated to humans providing therapeutic efficacy in the adult liver in addition to newborn. Overall, our data support the development of this liver-directed AAV-based knockin strategy.


Assuntos
Dependovirus , Modelos Animais de Doenças , Vetores Genéticos , Fígado , Animais , Dependovirus/genética , Fígado/metabolismo , Fígado/patologia , Camundongos , Vetores Genéticos/genética , Hepatócitos/metabolismo , Humanos , Integração Viral/genética , Sistemas CRISPR-Cas/genética , Transgenes , Doenças Genéticas Inatas/genética , Doenças Genéticas Inatas/terapia , Terapia Genética/métodos , Camundongos Endogâmicos C57BL , Albuminas/genética , Albuminas/metabolismo
3.
Biol Pharm Bull ; 47(7): 1241-1247, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38945897

RESUMO

Primary hepatocytes are valuable for studying liver diseases, drug-induced liver injury, and drug metabolism. However, when cultured in a two-dimensional (2D) environment, primary hepatocytes undergo rapid dedifferentiation via an epithelial-mesenchymal transition (EMT) and lose their liver-specific functions. On the other hand, a three-dimensional (3D) culture of primary hepatocyte organoids presents challenges for analyzing cellular functions and molecular behaviors due to strong cell-cell adhesion among heterogeneous cells. In this study, we developed a novel dispersion culture method of hepatocytes within a dome-shaped collagen matrix, overcoming conventional limitations. The expression levels of EMT-related genes were lower in rat primary hepatocytes cultured using this method for 4 d than in cells cultured using the 2D method. Furthermore, albumin production, a marker of liver function, declined sharply in rat primary hepatocytes cultured in two dimensions from 6.40 µg/mL/48 h on day 4 to 1.35 µg/mL/48 h on day 8, and declined gradually from 4.92 µg/mL/48 h on day 8 to 3.89 µg/mL/48 h on day 14 in rat primary hepatocytes cultured using our new method. These findings indicate that the newly developed culture method can suppress EMT and maintain liver functions for 14 d in rat primary hepatocytes, potentially expanding the utility of primary hepatocyte cultured by using conventional 3D methods.


Assuntos
Colágeno , Transição Epitelial-Mesenquimal , Hepatócitos , Fígado , Animais , Hepatócitos/metabolismo , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/fisiologia , Células Cultivadas , Colágeno/metabolismo , Masculino , Fígado/metabolismo , Fígado/citologia , Ratos , Técnicas de Cultura de Células/métodos , Ratos Sprague-Dawley , Albuminas/metabolismo
4.
J Physiol ; 602(14): 3575-3592, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38857419

RESUMO

In early diabetic nephropathy (DN), recent studies have shown that albuminuria stems mostly from alterations in tubular function rather than from glomerular damage. Several factors in DN, including hyperfiltration, hypertrophy and reduced abundance of the albumin receptors megalin and cubilin, affect albumin endocytosis in the proximal tubule (PT). To assess their respective contribution, we developed a model of albumin handling in the rat PT that couples the transport of albumin to that of water and solutes. Our simulations suggest that, under basal conditions, ∼75% of albumin is retrieved in the S1 segment. The model predicts negligible uptake in S3, as observed experimentally. It also accurately predicts the impact of acute hyperglycaemia on urinary albumin excretion. Simulations reproduce observed increases in albumin excretion in early DN by considering the combined effects of increased glomerular filtration rate (GFR), osmotic diuresis, hypertrophy, and megalin and cubilin downregulation, without stipulating changes in glomerular permselectivity. The results indicate that in isolation, glucose-elicited osmotic diuresis and glucose transporter upregulation raise albumin excretion only slightly. Enlargement of PT diameter not only augments uptake via surface area expansion, but also reduces fluid velocity and thus shear stress-induced stimulation of endocytosis. Overall, our model predicts that downregulation of megalin and cubilin and hyperfiltration both contribute significantly to increasing albumin excretion in rats with early-stage diabetes. The results also suggest that acute sodium-glucose cotransporter 2 inhibition lowers albumin excretion only if GFR decreases sufficiently, and that angiotensin II receptor blockers mitigate urinary albumin loss in early DN in large part by upregulating albumin receptor abundance. KEY POINTS: The urinary excretion of albumin is increased in early diabetic nephropathy (DN). It is difficult to experimentally disentangle the multiple factors that affect the renal handling of albumin in DN. We developed a mathematical model of albumin transport in the rat proximal tubule (PT) to examine the impact of elevated plasma glucose, hyperfiltration, PT hypertrophy and reduced abundance of albumin receptors on albumin uptake and excretion in DN. Our model predicts that glucose-elicited osmotic diuresis per se raises albumin excretion only slightly. Conversely, increases in PT diameter and length favour reduced albumin excretion. Our results suggest that downregulation of the receptors megalin and cubilin in PT cells and hyperfiltration both contribute significantly to increasing albumin excretion in DN. The model helps to better understand the mechanisms underlying urinary loss of albumin in early-stage diabetes, and the impact of specific treatments thereupon.


Assuntos
Nefropatias Diabéticas , Túbulos Renais Proximais , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Animais , Ratos , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/fisiopatologia , Túbulos Renais Proximais/metabolismo , Albuminas/metabolismo , Taxa de Filtração Glomerular , Receptores de Superfície Celular/metabolismo , Albuminúria/metabolismo , Modelos Biológicos , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Endocitose/fisiologia
5.
Mycotoxin Res ; 40(3): 433-445, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38743341

RESUMO

Ochratoxin A (OTA) is known to be strongly bound to serum albumin, but it remains unknown how albumin affects its metabolism and kinetics. To close this gap, we used a mouse model, where heterozygous albumin deletion reduces serum albumin to concentrations similar to hypoalbuminemic patients and completely eliminates albumin by a homozygous knockout. OTA and its potential metabolites (OTα, 4-OH-OTA, 7'-OH-OTA, OTHQ, OP-OTA, OTB-GSH, OTB-NAC, OTB) were time-dependently analyzed in plasma, bile, and urine by LC-MS/MS and were compared to previously published hepatotoxicity and nephrotoxicity data. Homozygous albumin deletion strongly accelerated plasma clearance as well as biliary and urinary excretion of the parent compound and its hydroxylation products. Decreasing albumin in mice by the heterozygous and even more by the homozygous knockout leads to an increase in the parent compound in urine which corresponded to increased nephrotoxicity. The role of albumin in OTA-induced hepatotoxicity is more complex, since heterozygous but not homozygous nor wild-type mice showed a strong biliary increase in the toxic open lactone OP-OTA. Correspondingly, OTA-induced hepatotoxicity was higher in heterozygous than in wild-type and homozygous animals. We present evidence that albumin-mediated retention of OTA in hepatocytes is required for formation of the toxic OP-OTA, while complete albumin elimination leads to rapid biliary clearance of OTA from hepatocytes with less formation of OP-OTA. In conclusion, albumin has a strong influence on metabolism and toxicity of OTA. In hypoalbuminemia, the parent OTA is associated with increased nephrotoxicity and the open lactone with increased hepatotoxicity.


Assuntos
Camundongos Knockout , Ocratoxinas , Ocratoxinas/metabolismo , Ocratoxinas/urina , Ocratoxinas/toxicidade , Animais , Camundongos , Espectrometria de Massas em Tandem , Albumina Sérica/metabolismo , Cromatografia Líquida , Albuminas/metabolismo , Masculino , Bile/metabolismo , Fígado/metabolismo , Fígado/efeitos dos fármacos , Camundongos Endogâmicos C57BL
6.
Theranostics ; 14(7): 2675-2686, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38773981

RESUMO

Cyanine dyes are widely used organic probes for in vivo imaging due to their tunable fluorescence. They can form complexes with endogenous albumin, resulting in enhanced brightness and photostability. However, this binding is uncontrollable and irreversible, leading to considerable nonspecific background signals and unregulated circulation time. Methods: Here, we connect varying numbers of 4-(4-iodophenyl) butanoic acid (IP) as albumin-binding moieties (ABM) to the cyanine dye, enabling dynamic and controllable binding with albumin. Meanwhile, we provide a blocking method to completely release the dye from covalent capture with albumin, resulting in specific targeting fluorescence. Furthermore, we evaluate the pharmacokinetics and tumor targeting of the developed dyes. Results: The engineered dyes can dynamically and selectively bind with multiple albumins to change the in situ size of assemblies and circulation time, providing programmable regulation over the imaging time window. The nucleophilic substitution of meso-Cl with water-soluble amino acids or targeting peptides for IP-engineered dye further addresses the nonspecific signals caused by albumin, allowing for adjustable angiography time and efficient tumor targeting. Conclusion: This study rationalizes the binding modes of dyes and proteins, applicable to a wide range of near-infrared (NIR) dyes for improving their in vivo molecular imaging.


Assuntos
Albuminas , Corantes Fluorescentes , Imagem Óptica , Animais , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacocinética , Albuminas/química , Albuminas/metabolismo , Imagem Óptica/métodos , Neoplasias/diagnóstico por imagem , Camundongos , Humanos , Carbocianinas/química , Camundongos Nus , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C
7.
Artigo em Inglês | MEDLINE | ID: mdl-38735125

RESUMO

Protein adducts are vital targets for exploring organophosphorus nerve agents (OPNAs) exposure and identification, that can be used to characterize the chemical burden and initiate chemical safety measures. However, the use of protein adducts as biomarkers of OPNA exposure has developed slowly. To further promote the development of biomarkers in chemical forensics, it is crucial to expand the range of modified peptides and active sites, and describe the characteristics of OPNA adducts at specific reaction sites. This study utilized multi-species and multi-source albumins as the protein targets. We identified 56 peptides in albumins from various species (including human, horse, rat and pig), that were modified by at least two OPNAs. Diverse modification characteristics were observed in response to certain agents: including (1) multiple sites on the same peptide modified by one or more agents, (2) different reactivities at the same site in homologous albumins, and (3) different preferences at the same active sites associated with differences in the biological matrix during exposure. Our studies provided an empirical reference with rationalized underpinnings supported by estimated conformation energetics through molecular modeling. We employed different peptide markers for detection of protein adducts, as (one would do) in forensic screening for identification and quantification of chemical damage. Three characteristic peptides were screened and analyzed in human albumin, including Y287ICENQDSISSK, K438VPQVS443TPTLVEVSR, and Y162LY164EIAR. Stable fragment ions with neutral loss were found from their tandem MS/MS spectra, which were used as characteristic ions for identification and extraction of modified peptides in enzymatic digestion mixtures. Coupling these observations with computer simulations, we found that the structural stability of albumin and albumin-adduct complexes (as well as the effective force that promotes stability of different adducts) changes in the interval before and after adduct formation. In pig albumin, five active peptides existed stably in vivo and in vitro. Most of them can be detected within 30 min after OPNA exposure, and the detection window can persist about half a month. These early findings provided the foundation and rationale for utilizing pig albumin as a sampling target for rapid analysis in future forensic work.


Assuntos
Agentes Neurotóxicos , Compostos Organofosforados , Animais , Humanos , Ratos , Compostos Organofosforados/química , Suínos , Agentes Neurotóxicos/química , Agentes Neurotóxicos/análise , Cavalos , Espectrometria de Massas em Tandem/métodos , Peptídeos/química , Peptídeos/análise , Albuminas/química , Albuminas/metabolismo , Biomarcadores/análise , Biomarcadores/química
8.
J Transl Med ; 22(1): 454, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741158

RESUMO

BACKGROUND: Glycosylation is an enzyme-catalyzed post-translational modification that is distinct from glycation and is present on a majority of plasma proteins. N-glycosylation occurs on asparagine residues predominantly within canonical N-glycosylation motifs (Asn-X-Ser/Thr) although non-canonical N-glycosylation motifs Asn-X-Cys/Val have also been reported. Albumin is the most abundant protein in plasma whose glycation is well-studied in diabetes mellitus. However, albumin has long been considered a non-glycosylated protein due to absence of canonical motifs. Albumin contains two non-canonical N-glycosylation motifs, of which one was recently reported to be glycosylated. METHODS: We enriched abundant serum proteins to investigate their N-linked glycosylation followed by trypsin digestion and glycopeptide enrichment by size-exclusion or mixed-mode anion-exchange chromatography. Glycosylation at canonical as well as non-canonical sites was evaluated by liquid chromatography-tandem mass spectrometry (LC-MS/MS) of enriched glycopeptides. Deglycosylation analysis was performed to confirm N-linked glycosylation at non-canonical sites. Albumin-derived glycopeptides were fragmented by MS3 to confirm attached glycans. Parallel reaction monitoring was carried out on twenty additional samples to validate these findings. Bovine and rabbit albumin-derived glycopeptides were similarly analyzed by LC-MS/MS. RESULTS: Human albumin is N-glycosylated at two non-canonical sites, Asn68 and Asn123. N-glycopeptides were detected at both sites bearing four complex sialylated glycans and validated by MS3-based fragmentation and deglycosylation studies. Targeted mass spectrometry confirmed glycosylation in twenty additional donor samples. Finally, the highly conserved Asn123 in bovine and rabbit serum albumin was also found to be glycosylated. CONCLUSIONS: Albumin is a glycoprotein with conserved N-linked glycosylation sites that could have potential clinical applications.


Assuntos
Albuminas , Glicoproteínas , Glicosilação , Animais , Bovinos , Humanos , Albuminas/metabolismo , Sequência de Aminoácidos , Cromatografia Líquida , Glicopeptídeos/metabolismo , Glicopeptídeos/química , Glicoproteínas/metabolismo , Glicoproteínas/química , Dados de Sequência Molecular , Espectrometria de Massas em Tandem
9.
Poult Sci ; 103(7): 103784, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38713992

RESUMO

Hatchability could be quite different among individuals of indigenous chicken breed which might be affected by the egg quality. In this study, hatchability was individually recorded among 800 forty-wk-old Huainan partridge chickens. The chickens were then divided into high and low hatchability groups (HH and LH group) with 50 birds in each group. Egg quality was further determined in the 2 groups. Eight birds from each group were selected for slaughtering and tissue, responsible for egg formation, collection for structure observation by staining and candidate gene expression by transcriptome analysis. The hatchability in HH was 100% and 61.18% in LH. The eggshell thickness and shell strength were significantly lower, while the albumen height and Haugh unit were significantly higher in HH group than those in LH group (P < 0.05). The magnum weight and index, and the expression of polypeptide N-acetylgalactosaminyltransferase 9 (GALNT9), which responsible for thick albumen synthesis, in HH group were also significantly higher than that of LH group (P < 0.05). Compared with the LH group, there were 702 differentially expressed genes (DEGs) in HH group, of which 402 were up-regulated and 300 were down-regulated. Candidate genes of calbindin 1 (CALB1) and solute carrier family 26 member 9 (SLC26A9), which regulate calcium signaling pathway so as to affect Ca2+ transportation, exhibited significant high and low expression, respectively, in HH group compared to those in LH group (P < 0.05). Therefore, indigenous chicken with high expression of GALNT9 in magnum to form thick albumen to provide more protein for embryo, while high CALB1 and low expression of SLC26A9 to decrease Ca2+ transportation so as to form a thinner eggshell and provide better gas exchange during embryo development.


Assuntos
Galinhas , Casca de Ovo , N-Acetilgalactosaminiltransferases , Animais , Casca de Ovo/fisiologia , Galinhas/genética , Galinhas/fisiologia , N-Acetilgalactosaminiltransferases/genética , N-Acetilgalactosaminiltransferases/metabolismo , Cálcio/metabolismo , Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Albuminas/metabolismo , Albuminas/genética , Óvulo/fisiologia , Expressão Gênica , Perfilação da Expressão Gênica/veterinária
10.
Curr Med Sci ; 44(3): 648-656, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38748371

RESUMO

OBJECTIVE: Sepsis is considered a major cause of health loss in children and had high mortality and morbidity. Currently, there is no reliable model for predicting the prognosis of pediatric patients with sepsis. This study aimed to analyze the clinical characteristics of sepsis in children and assess the risk factors associated with poor prognosis in pediatric sepsis patients to identify timely interventions and improve their outcomes. METHODS: This study analyzed the clinical indicators and laboratory results of septic patients hospitalized in the Pediatric Intensive Care Unit of Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, China, from January 1, 2019, to December 31, 2021. Risk factors for sepsis were identified by logistic regression analyses. RESULTS: A total of 355 children with sepsis were enrolled, with 333 children (93.8%) in the good prognosis group, and 22 children (6.2%) in the poor prognosis group. Among them, there were 255 patients (71.8%) in the sepsis group, and 100 patients (28.2%) in the severe sepsis group. The length of hospital stay in the poor prognosis group was longer than that in the good prognosis group (P<0.01). The levels of interleukin 1ß (IL-1ß) in the poor prognosis group were higher than those in the good prognosis group (P>0.05), and the platelet (PLT), albumin (ALB), and hemoglobin (Hb) levels were lower in the poor prognosis group (P<0.01). The IL-8 levels in the severe sepsis group were higher than those in the sepsis group (P<0.05). Multiple logistic regression analysis suggested that lower Hb levels, ALB levels, peak PLT counts, and higher IL-1ß levels were independent risk factors for poor prognosis in children with sepsis. CONCLUSION: Lower Hb, ALB, and PLT counts and elevated IL-1ß are independent risk factors for poor prognosis in children with sepsis.


Assuntos
Unidades de Terapia Intensiva Pediátrica , Sepse , Humanos , Masculino , Recém-Nascido , Pré-Escolar , Sepse/sangue , Sepse/mortalidade , Tempo de Internação , Prognóstico , China/epidemiologia , Fatores de Risco , Interleucina-1beta/sangue , Interleucina-8/sangue , Hemoglobinas/metabolismo , Contagem de Plaquetas , Albuminas/metabolismo
11.
Sci Total Environ ; 926: 172087, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38561129

RESUMO

The main components of particulate matter (PM) had been reported to change DNA methylation levels. However, the mixed effect of PM and its constituents on DNA methylation and the underlying mechanism in children has not been well characterized. To investigate the association between single or mixture exposures and global DNA methylation or DNA methyltransferases (DNMTs), 273 children were recruited (110 in low-exposed area and 163 in high-exposed area) in China. Serum benzo[a]pyridin-7,8-dihydroglycol-9, 10-epoxide (BPDE)-albumin adduct and urinary metals were determined as exposure markers. The global DNA methylation (% 5mC) and the mRNA expression of DNMT1, and DNMT3A were measured. The linear regression, quantile-based g-computation (QGC), and mediation analyses were performed to investigate the effects of individual and mixture exposure. We found that significantly lower levels of % 5mC (P < 0.001) and the mRNA expression of DNMT3A in high-PM exposed group (P = 0.031). After adjustment for age, gender, BMI z-score, detecting status of urinary cotinine, serum folate, and white blood cells, urinary arsenic (As) was negatively correlated with the % 5mC. One IQR increase in urinary As (19.97 µmol/mol creatinine) was associated with a 11.06 % decrease in % 5mC (P = 0.026). Serum BPDE-albumin adduct and urinary cadmium (Cd) were negatively correlated with the levels of DNMT1 and DNMT3A (P < 0.05). Mixture exposure was negatively associated with expression of DNMT3A in QGC analysis (ß: -0.19, P < 0.001). Mixture exposure was significantly associated with decreased % 5mC in the children with non-detected cotinine or normal serum folate (P < 0.05), which the most contributors were PAHs and As. The mediated effect of hypomethylation through DNMT1 or DNMT3A pathway was not observed. Our findings indicated that individual and mixture exposure PAHs and metal components had negative associations with global DNA methylation and decreased DNMT3A expression significantly in school-age individuals.


Assuntos
Metilação de DNA , Hidrocarbonetos Policíclicos Aromáticos , Criança , Humanos , 7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido , Cotinina , Material Particulado , Poeira , DNA , Albuminas/metabolismo , Estudantes , Ácido Fólico , RNA Mensageiro/metabolismo
12.
Mol Pharm ; 21(5): 2473-2483, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38579335

RESUMO

In recent years, the drainage of fluids, immune cells, antigens, fluorescent tracers, and other solutes from the brain has been demonstrated to occur along lymphatic outflow pathways to the deep cervical lymph nodes in the neck. To the best of our knowledge, no studies have evaluated the lymphatic transport of therapeutics from the brain. The objective of this study was to determine the lymphatic transport of model therapeutics of different molecular weights and lipophilicity from the brain using cervical lymph cannulation and ligation models in rats. To do this, anesthetized Sprague-Dawley rats were cannulated at the carotid artery and cannulated, ligated, or left intact at the cervical lymph duct. Rats were administered 14C-ibuprofen (206.29 g/mol, logP 3.84), 3H-halofantrine HCl (536.89 g/mol, logP 8.06), or 3H-albumin (∼65,000 g/mol) via direct injection into the brain striatum at a rate of 0.5 µL/min over 16 min. Plasma or cervical lymph samples were collected for up to 6-8 h following dosing, and brain and lymph nodes were collected at 6 or 8 h. Samples were subsequently analyzed for radioactivity levels via scintillation counting. For 14C-ibuprofen, plasma concentrations over time (plasma AUC0-6h) were >2 fold higher in lymph-ligated rats than in lymph-intact rats, suggesting that ibuprofen is cleared from the brain primarily via nonlymphatic routes (e.g., across the blood-brain barrier) but that this clearance is influenced by changes in lymphatic flow. For 3H-halofantrine, >73% of the dose was retained at the brain dosing site in lymph-intact and lymph-ligated groups, and plasma AUC0-8h values were low in both groups (<0.3% dose.h/mL), consistent with the high retention in the brain. It was therefore not possible to determine whether halofantrine undergoes lymphatic transport from the brain within the duration of the study. For 3H-albumin, plasma AUC0-8h values were not significantly different between lymph-intact, lymph-ligated, and lymph-cannulated rats. However, >4% of the dose was recovered in cervical lymph over 8 h. Lymph/plasma concentration ratios of 3H-albumin were also very high (up to 53:1). Together, these results indicate that 3H-albumin is transported from the brain not only via lymphatic routes but also via the blood. Similar to other tissues, the lymphatics may thus play a significant role in the transport of macromolecules, including therapeutic proteins, from the brain but are unlikely to be a major transport pathway from the brain for small molecule drugs that are not lipophilic. Our rat cervical lymph cannulation model can be used to quantify the lymphatic drainage of different molecules and factors from the brain.


Assuntos
Encéfalo , Ibuprofeno , Linfonodos , Ratos Sprague-Dawley , Animais , Ratos , Encéfalo/metabolismo , Masculino , Linfonodos/metabolismo , Ibuprofeno/farmacocinética , Ibuprofeno/administração & dosagem , Ibuprofeno/química , Fenantrenos/farmacocinética , Fenantrenos/química , Fenantrenos/administração & dosagem , Transporte Biológico/fisiologia , Albuminas/farmacocinética , Albuminas/metabolismo
13.
Theranostics ; 14(6): 2605-2621, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646639

RESUMO

Rationale: Nab-paclitaxel (Abx) is widely employed in malignant tumor therapy. In tumor cells and pro-tumoral M2-type macrophages, the IL4 receptor (IL4R) is upregulated. This study aimed to elucidate the selective delivery of Abx to M2-type macrophages by targeting IL4R and reprogramming them into an anti-tumoral M1-type. Methods: Abx was conjugated with the IL4R-binding IL4RPep-1 peptide using click chemistry (IL4R-Abx). Cellular internalization, macrophage reprogramming and signal pathways, and tumor growth and metastasis by IL4R-Abx were examined. Results: IL4R-Abx was internalized into M2 macrophages more efficiently compared to the unmodified Abx and control peptide-conjugated Abx (Ctrl-Abx), which was primarily inhibited using an anti-IL4R antibody and a receptor-mediated endocytosis inhibitor compared with a macropinocytosis inhibitor. IL4R-Abx reprogrammed the M2-type macrophages into M1-like phenotype and increased reactive oxygen species (ROS) levels and extracellular release of high mobility group box 1 (HMGB1) in M2 macrophages at higher levels than Abx and Ctrl-Abx. The conditioned medium of IL4R-Abx-treated M2 macrophages skewed M2 macrophages into the M1-like phenotype, in which an anti-HMGB1 antibody and a toll-like receptor 4 (TLR4) inhibitor induced a blockade. IL4R-Abx accumulated at tumors, heightened immune-stimulatory cells while reducing immune-suppressing cells, and hampered tumor growth and metastasis in mice more efficiently than Abx and Ctrl-Abx. Conclusions: These results indicate that IL4R-targeting allows enhancement of M2-macrophage shaping into M1-like phenotype by Abx through the ROS-HMGB1-TLR4 axis, improvement of antitumor immunity, and thereby inhibition of tumor growth and metastasis, presenting a new approach to cancer immunotherapy.


Assuntos
Albuminas , Proteína HMGB1 , Macrófagos , Paclitaxel , Espécies Reativas de Oxigênio , Receptor 4 Toll-Like , Animais , Receptor 4 Toll-Like/metabolismo , Proteína HMGB1/metabolismo , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Paclitaxel/farmacologia , Albuminas/metabolismo , Receptores de Interleucina-4/metabolismo , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacos , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neoplasias/metabolismo , Camundongos Endogâmicos C57BL , Fenótipo , Camundongos Endogâmicos BALB C , Metástase Neoplásica , Feminino
14.
Drug Metab Dispos ; 52(6): 548-554, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38604729

RESUMO

Extrapolating in vivo hepatic clearance from in vitro uptake data is a known challenge, especially for organic anion-transporting polypeptide transporter (OATP) substrates, and the well-stirred model (WSM) commonly yields systematic underpredictions for those anionic drugs, hypothetically due to "albumin-mediated hepatic drug uptake". In the present study, we demonstrate that the WSM incorporating the dynamic free fraction (f D), a measure of drug protein binding affinity, performs reasonably well in predicting hepatic clearance of OATP substrates. For a selection of anionic drugs, including atorvastatin, fluvastatin, pravastatin, rosuvastatin, pitavastatin, cerivastatin, and repaglinide, this dynamic well-stirred model (dWSM) correctly predicts hepatic plasma clearance within 2-fold error for six out of seven OATP substrates examined. The geometric mean of clearance ratios between the predicted and the observed values falls in the range of 1.21-1.38. As expected, the WSM with unbound fraction (f u) systematically underpredicts hepatic clearance with greater than 2-fold error for five out of seven drugs, and the geometric mean of clearance ratios between the predicted and the observed values is in the range of 0.20-0.29. The results suggest that, despite its simplicity, the dWSM operates well for transporter-mediated uptake clearance, and that clearance under-prediction of OATP substrates may not necessarily be associated with the chemical class of the anionic drugs, nor is it a result of albumin-mediated hepatic drug uptake as currently hypothesized. Instead, the superior prediction power of the dWSM confirms the utility of the dynamic free fraction in clearance prediction and the importance of drug plasma binding kinetics in hepatic uptake clearance. SIGNIFICANCE STATEMENT: The traditional well-stirred model (WSM) consistently underpredicts organin anion-transporting polypeptide transporter (OATP)-mediated hepatic uptake clearance, hypothetically due to the albumin-mediated hepatic drug uptake. In this manuscript, we apply the dynamic WSM to extrapolate hepatic clearance of the OATP substrates, and our results show significant improvements in clearance prediction without assuming albumin-mediated hepatic drug uptake.


Assuntos
Fígado , Modelos Biológicos , Transportadores de Ânions Orgânicos , Transportadores de Ânions Orgânicos/metabolismo , Fígado/metabolismo , Humanos , Albuminas/metabolismo , Transporte Biológico/fisiologia , Taxa de Depuração Metabólica , Ligação Proteica , Preparações Farmacêuticas/metabolismo , Animais
15.
Biochim Biophys Acta Mol Basis Dis ; 1870(5): 167155, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38579939

RESUMO

Tubular proteinuria is a common feature in COVID-19 patients, even in the absence of established acute kidney injury. SARS-CoV-2 spike protein (S protein) was shown to inhibit megalin-mediated albumin endocytosis in proximal tubule epithelial cells (PTECs). Angiotensin-converting enzyme type 2 (ACE2) was not directly involved. Since Toll-like receptor 4 (TLR4) mediates S protein effects in various cell types, we hypothesized that TLR4 could be participating in the inhibition of PTECs albumin endocytosis elicited by S protein. Two different models of PTECs were used: porcine proximal tubule cells (LLC-PK1) and human embryonic kidney cells (HEK-293). S protein reduced Akt activity by specifically inhibiting of threonine 308 (Thr308) phosphorylation, a process mediated by phosphoinositide-dependent kinase 1 (PDK1). GSK2334470, a PDK1 inhibitor, decreased albumin endocytosis and megalin expression mimicking S protein effect. S protein did not change total TLR4 expression but decreased its surface expression. LPS-RS, a TLR4 antagonist, also counteracted the effects of the S protein on Akt phosphorylation at Thr308, albumin endocytosis, and megalin expression. Conversely, these effects of the S protein were replicated by LPS, an agonist of TLR4. Incubation of PTECs with a pseudovirus containing S protein inhibited albumin endocytosis. Null or VSV-G pseudovirus, used as control, had no effect. LPS-RS prevented the inhibitory impact of pseudovirus containing the S protein on albumin endocytosis but had no influence on virus internalization. Our findings demonstrate that the inhibitory effect of the S protein on albumin endocytosis in PTECs is mediated through TLR4, resulting from a reduction in megalin expression.


Assuntos
Endocitose , Túbulos Renais Proximais , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Receptor 4 Toll-Like , Receptor 4 Toll-Like/metabolismo , Endocitose/efeitos dos fármacos , Humanos , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/virologia , Animais , Glicoproteína da Espícula de Coronavírus/metabolismo , SARS-CoV-2/metabolismo , Células HEK293 , Suínos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosforilação , COVID-19/metabolismo , COVID-19/virologia , COVID-19/patologia , Albuminas/metabolismo , Células LLC-PK1 , Células Epiteliais/metabolismo , Células Epiteliais/virologia
16.
Cells ; 13(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38607033

RESUMO

Research into the neonatal Fc receptor (FcRn) has increased dramatically ever since Simister and Mostov first purified a rat version of the receptor. Over the years, FcRn has been shown to function not only as a receptor that transfers immunity from mother to fetus but also performs an array of different functions that include transport and recycling of immunoglobulins and albumin in the adult. Due to its important cellular roles, several clinical trials have been designed to either inhibit/enhance FcRn function or develop of non-invasive therapeutic delivery system such as fusion of drugs to IgG Fc or albumin to enhance delivery inside the cells. Here, we report the accidental identification of several FcRn alternatively spliced variants in both mouse and human cells. The four new mouse splice variants are capable of binding immunoglobulins' Fc and Fab portions. In addition, we have identified FcRn-specific vesicles in which immunoglobulins and albumin can be stored and that are involved in the endosomal-lysosomal system. The complexity of FcRn functions offers significant potential to design and develop novel and targeted therapeutics.


Assuntos
Receptores Fc , Animais , Humanos , Camundongos , Ratos , Albuminas/metabolismo , Endossomos/metabolismo , Imunoglobulina G/metabolismo , Receptores Fc/genética , Receptores Fc/metabolismo , Isoformas de Proteínas
17.
Ann Nucl Med ; 38(7): 574-583, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38676906

RESUMO

OBJECTIVE: The marked success of prostate-specific membrane antigen (PSMA)-targeting radioligands with albumin binder (ALB) is attributed to the improvement of blood retention and tumor accumulation. [111In]In-PNT-DA1, our PSMA-targeting radioligand with ALB, also achieved improved tumor accumulation due to its prolonged blood retention. Although the advantage of ALBs is related to their reversible binding to albumin, the relationship between albumin-binding and tumor accumulation of PSMA-targeting radioligands remains unclear because of the lack of information about radioligands with stronger albumin-binding than ALBs. In this study, we designed and synthesized [111In]In-PNT-DM-HSA, a new radioligand that consists of a PSMA-targeting radioligand covalently bound to albumin. The pharmacokinetics of [111In]In-PNT-DM-HSA was compared with those of [111In]In-PNT-DA1 and [111In]In-PSMA-617, a non-ALB-conjugated radioligand, to evaluate the relationship between albumin-binding and tumor accumulation. METHOD: The [111In]In-PNT-DM-HSA was prepared by incubation of [111In]In-PNT-DM, a PSMA-targeting radioligand including a maleimide group, and human serum albumin (HSA). The ability of [111In]In-PNT-DM-HSA was evaluated by in vitro assays. A biodistribution study using LNCaP tumor-bearing mice was conducted to compare the pharmacokinetics of [111In]In-PNT-DM-HSA, [111In]In-PNT-DA1, and [111In]In-PSMA-617. RESULTS: The [111In]In-PNT-DM-HSA was obtained at a favorable radiochemical yield and high radiochemical purity. In vitro assays revealed that [111In]In-PNT-DM-HSA had fundamental characteristics as a PSMA-targeting radioligand interacting with albumin covalently. In a biodistribution study, [111In]In-PNT-DM-HSA and [111In]In-PNT-DA1 showed higher blood retention than [111In]In-PSMA-617. On the other hand, the tumor accumulation of [111In]In-PNT-DA1 was much higher than [111In]In-PNT-DM-HSA and [111In]In-PSMA-617. CONCLUSIONS: These results indicate that the moderate reversible binding of ALB with albumin, not covalent binding, may play a critical role in enhancing the tumor accumulation of PSMA-targeting radioligands.


Assuntos
Antígenos de Superfície , Glutamato Carboxipeptidase II , Animais , Camundongos , Glutamato Carboxipeptidase II/metabolismo , Antígenos de Superfície/metabolismo , Humanos , Masculino , Ligantes , Linhagem Celular Tumoral , Distribuição Tecidual , Ligação Proteica , Albuminas/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/diagnóstico por imagem , Albumina Sérica/metabolismo , Albumina Sérica/química , Dipeptídeos/farmacocinética , Dipeptídeos/química , Dipeptídeos/metabolismo , Radioisótopos de Índio
18.
J Mater Chem B ; 12(18): 4441-4450, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38639071

RESUMO

In this study, we report a small molecule optical marker BI-CyG derived from the structural engineering of a cyanine scaffold. The developed probe offers suitable advantages over existing cyanine-based albumin specific probes in terms of its excitation and emission wavelengths, which are 760 and 830-832 nm, respectively. Structural tuning of the cyanine architecture leading to extended π-conjugation and resulting in a suitable bathochromic shift in the emission wavelength of the probe is represented in this study. The probe besides emitting in the NIR region, also possesses the desirable characteristics of being a potential target selective optical marker, as established from various biophysical studies. Molecular modelling and simulation studies provided critical insights into the binding of the probe in the protein microenvironment, which was further supported by experimental studies. The probe displayed intracellular albumin selectivity and was utilized for demonstrating alteration in albumin levels in pathological states such as hyperglycemia in hepatic cells. The present study also sheds some light on using BI-CyG as an imaging probe and on the role of metformin as a suitable drug for balancing hyperglycemia-induced reduced intra-hepatic albumin levels. The study, thus, attempts to highlight the structural derivatization of cyanine to afford a potential probe for serum albumin and its deployment to image altering albumin levels in an induced pathological condition, hyperglycemia.


Assuntos
Albuminas , Carbocianinas , Hiperglicemia , Animais , Humanos , Albuminas/química , Albuminas/metabolismo , Carbocianinas/química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Hiperglicemia/metabolismo , Sondas Moleculares/química , Estrutura Molecular , Imagem Óptica
19.
Am J Physiol Renal Physiol ; 326(6): F1041-F1053, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38660713

RESUMO

Beyond glycemic control, SGLT2 inhibitors (SGLT2is) have protective effects on cardiorenal function. Renoprotection has been suggested to involve inhibition of NHE3 leading to reduced ATP-dependent tubular workload and mitochondrial oxygen consumption. NHE3 activity is also important for regulation of endosomal pH, but the effects of SGLT2i on endocytosis are unknown. We used a highly differentiated cell culture model of proximal tubule (PT) cells to determine the direct effects of SGLT2i on Na+-dependent fluid transport and endocytic uptake in this nephron segment. Strikingly, canagliflozin but not empagliflozin reduced fluid transport across cell monolayers and dramatically inhibited endocytic uptake of albumin. These effects were independent of glucose and occurred at clinically relevant concentrations of drug. Canagliflozin acutely inhibited surface NHE3 activity, consistent with a direct effect, but did not affect endosomal pH or NHE3 phosphorylation. In addition, canagliflozin rapidly and selectively inhibited mitochondrial complex I activity. Inhibition of mitochondrial complex I by metformin recapitulated the effects of canagliflozin on endocytosis and fluid transport, whereas modulation of downstream effectors AMPK and mTOR did not. Mice given a single dose of canagliflozin excreted twice as much urine over 24 h compared with empagliflozin-treated mice despite similar water intake. We conclude that canagliflozin selectively suppresses Na+-dependent fluid transport and albumin uptake in PT cells via direct inhibition of NHE3 and of mitochondrial function upstream of the AMPK/mTOR axis. These additional targets of canagliflozin contribute significantly to reduced PT Na+-dependent fluid transport in vivo.NEW & NOTEWORTHY Reduced NHE3-mediated Na+ transport has been suggested to underlie the cardiorenal protection provided by SGLT2 inhibitors. We found that canagliflozin, but not empagliflozin, reduced NHE3-dependent fluid transport and endocytic uptake in cultured proximal tubule cells. These effects were independent of SGLT2 activity and resulted from inhibition of mitochondrial complex I and NHE3. Studies in mice are consistent with greater effects of canagliflozin versus empagliflozin on fluid transport. Our data suggest that these selective effects of canagliflozin contribute to reduced Na+-dependent transport in proximal tubule cells.


Assuntos
Canagliflozina , Túbulos Renais Proximais , Inibidores do Transportador 2 de Sódio-Glicose , Trocador 3 de Sódio-Hidrogênio , Animais , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/enzimologia , Trocador 3 de Sódio-Hidrogênio/metabolismo , Canagliflozina/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Camundongos , Masculino , Transportador 2 de Glucose-Sódio/metabolismo , Endocitose/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Albuminas/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Compostos Benzidrílicos , Glucosídeos
20.
Biomater Sci ; 12(11): 2978-2992, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38683548

RESUMO

Inhalable nanomedicines are increasingly being developed to optimise the pharmaceutical treatment of respiratory diseases. Large lipid-based nanosystems at the forefront of the inhalable nanomedicines development pipeline, though, have a number of limitations. The objective of this study was, therefore, to investigate the utility of novel small lipidated sulfoxide polymers based on poly(2-(methylsulfinyl)ethyl acrylate) (PMSEA) as inhalable drug delivery platforms with tuneable membrane permeability imparted by differential albumin binding kinetics. Linear PMSEA (5 kDa) was used as a hydrophilic polymer backbone with excellent anti-fouling and stealth properties compared to poly(ethylene glycol). Terminal lipids comprising single (1C2, 1C12) or double (2C12) chain diglycerides were installed to provide differing affinities for albumin and, by extension, albumin trafficking pathways in the lungs. Albumin binding kinetics, cytotoxicity, lung mucus penetration and cellular uptake and permeability through key cellular barriers in the lungs were examined in vitro. The polymers showed good mucus penetration and no cytotoxicity over 24 h at up to 1 mg ml-1. While 1C2-showed no interaction with albumin, 1C12-PMSEA and 2C12-PMSEA bound albumin with KD values of approximately 76 and 10 µM, respectively. Despite binding to albumin, 2C12-PMSEA showed reduced cell uptake and membrane permeability compared to the smaller polymers and the presence of albumin had little effect on cell uptake and membrane permeability. While PMSEA strongly shielded these lipids from albumin, the data suggest that there is scope to tune the lipid component of these systems to control membrane permeability and cellular interactions in the lungs to tailor drug disposition in the lungs.


Assuntos
Lipídeos , Humanos , Animais , Lipídeos/química , Polímeros/química , Administração por Inalação , Sistemas de Liberação de Medicamentos , Albuminas/química , Albuminas/metabolismo , Pulmão/metabolismo , Ligação Proteica , Portadores de Fármacos/química
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