RESUMEN
It was recently reported that the dexmedetomidine concentration within the extracorporeal circuit decreases with co-administration of midazolam. In this study, we investigated whether displacement of dexmedetomidine by midazolam from the binding site of major plasma proteins, human serum albumin (HSA) and α1-acid glycoprotein (AAG), would increase levels of free dexmedetomidine that could be adsorbed to the circuit. Equilibrium dialysis experiments indicated that dexmedetomidine binds to a single site on both HSA and AAG with four times greater affinity than midazolam. Midazolam-mediated inhibition of the binding of dexmedetomidine to HSA and AAG was also examined. The binding of dexmedetomidine to these proteins decreased in the presence of midazolam. Competitive binding experiments suggested that the inhibition of binding by midazolam was due to competitive displacement at site II of HSA and due to non-competitive displacement at the site of AAG. Thus, our present data indicate that free dexmedetomidine displaced by midazolam from site II of HSA or from AAG is adsorbed onto extracorporeal circuits, resulting in a change in the dexmedetomidine concentration within the circuit.
Asunto(s)
Dexmedetomidina , Midazolam , Humanos , Unión Proteica/fisiología , Dexmedetomidina/farmacología , Proteínas Sanguíneas/metabolismo , Orosomucoide/metabolismo , Albúmina Sérica Humana/metabolismoRESUMEN
Restoration of blood flow in skeletal muscle after a prolonged period of ischemia induces muscular ischemia-reperfusion injury, leading to local injury/dysfunction in muscles followed by systemic inflammatory responses. However, preventive/curative agents for skeletal muscle ischemia injury are unavailable in clinics to date. Increasing evidence has validated that carbon monoxide (CO) prevents the progression of ischemia-reperfusion injury in various organs owing to its versatile bioactivity. Previously, we developed a bioinspired CO donor, CO-bound red blood cells (CO-RBC), which mimics the dynamics of RBC-associated CO in the body. In the present study, we have tested the therapeutic potential of CO-RBC in muscular injury/dysfunction and secondary systemic inflammation induced by skeletal muscle ischemia-reperfusion. The results indicate that CO-RBC rather than RBC alone suppressed elevation of plasma creatine phosphokinase, a marker of muscular injury, in rats subjected to both hind limbs ischemia-reperfusion. In addition, the results of the treadmill walking test revealed a significantly decreased muscular motor function in RBC-treated rats subjected to both hind limbs ischemia-reperfusion than that in healthy rats, however, CO-RBC treatment facilitated sustained muscular motor functions after hind limbs ischemia-reperfusion. Furthermore, CO-RBC rather than RBC suppressed the production of tumour necrosis factor (TNF)-α and interleukin (IL)-6, which were upregulated by muscular ischemia-reperfusion. Interestingly, CO-RBC treatment induced higher levels of IL-10 compared to saline or RBC treatments. Based on these findings, we suggest that CO-RBC exhibits a suppressive effect against skeletal muscle injury/dysfunction and systemic inflammatory responses after skeletal muscle ischemia-reperfusion.
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Monóxido de Carbono , Inflamación , Músculo Esquelético , Ratas Sprague-Dawley , Daño por Reperfusión , Animales , Daño por Reperfusión/tratamiento farmacológico , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Masculino , Inflamación/tratamiento farmacológico , Eritrocitos/efectos de los fármacos , Eritrocitos/metabolismo , Ratas , Creatina Quinasa/sangre , Miembro Posterior/irrigación sanguínea , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/sangre , Interleucina-6/metabolismo , Interleucina-6/sangreRESUMEN
In the process of the drug development, studies on the cytochrome P450 (CYP) profiles after its administration provided fundamental information regarding drug interactions with concomitantly administered drugs. Here, we evaluated the influence of the administration of H12-(ADP)-liposomes, a platelet substitute, on the mRNA and protein expression, and metabolic activity of CYPs, with focus on the CYP1A2, CYP2C11 and CYP3A2, in rat liver.At 24 h after administering saline or H12-(ADP)-liposomes (10 mg of lipids/kg), a quantitative RT-PCR and western blot analysis revealed that the mRNA and proteins expression of all of the target hepatic CYP isoforms were not different between the saline and H12-(ADP)-liposome groups. Furthermore, an ex vivo CYP metabolic activity assay showed that hepatic CYP metabolic activities in the H12-(ADP)-liposome group were comparable to the corresponding saline group. On the other hand, the area under the blood concentration-time curve for substitutes for CYP1A2 and CYP2C11 was higher in H12-(ADP)-liposome group than in saline group, but the degree of elevations was negligible levels.At a minimum, based on these results, we conclude that H12-(ADP)-liposomes have no quantitative and qualitative effect on the hepatic CYP isoforms, indicating that the drug interactions of H12-(ADP)-liposomes with CYP-metabolizing drugs would be negligible.
RESUMEN
Pirarubicin (THP) shows more rapid intracellular uptake, more effective antitumor activity, and less cardiac toxicity, compared to doxorubicin. However, THP is distributed to both tumor and normal tissues indiscriminately. This study aimed to develop a nanosuspension to deliver THP to tumor tissues more efficiently. Fatty-acid-modified THPs (FA-THPs; octanoic acid, dodecanoic acid, palmitic acid-THPs) were synthesized to increase the hydrophobicity of THP. Nanosuspensions of these FA-THPs were then prepared using an antisolvent precipitation technique. Among the FA-THPs, the most efficiently drug-loaded nanosuspension was obtained from palmitic acid-THP (pal-THP) using an aqueous antisolvent containing bovine serum albumin as a stabilizer. The pal-THP nanoparticles in the nanosuspension were confirmed to be of optimal size (100-125 nm) for delivery to tumor tissues using dynamic light scattering and transmission electron microscopy. The pal-THP nanosuspension showed cytotoxicity in colon 26 cells. The nanosuspension was shown to disintegrate in the presence of surfactants such as lecithin, liberating pal-THP, which was converted to free THP in acidic media. It is therefore proposed that pal-THP nanoparticles that reach tumor cells after intravenous administration would exert antitumor effect by liberating pal-THP (i.e., disintegration of nanoparticles by the interaction with cell membrane), followed by the release of free THP in the acidic milieu of tumor cells. These findings indicate that FA-THP nanosuspensions, particularly pal-THP nanosuspension, hold promise as a candidate for cancer treatment. However, further in vivo studies are necessary.
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Ácidos Grasos , Nanopartículas , Ácido Palmítico , Doxorrubicina/farmacología , Albúmina Sérica Bovina , Suspensiones , Tamaño de la Partícula , SolubilidadRESUMEN
4-phenylbutyrate (PB) and structurally related compounds hold promise for treating many diseases, including cancers. However, pharmaceutical limitations, such as an unpleasant taste or poor aqueous solubility, impede their evaluation and clinical use. This study explores cyclodextrin (CD) complexation as a strategy to address these limitations. The structural chemistry of the CD complexes of these compounds was analyzed using phase solubility, nuclear magnetic resonance (NMR) spectroscopic techniques, and molecular modeling to inform the choice of CD for such application. The study revealed that PB and its shorter-chain derivative form 1:1 αCD complexes, while the longer-chain derivatives form 1:2 (guest:host) complexes. αCD includes the alkyl chain of the shorter-chain compounds, depositing the phenyl ring around its secondary rim, whereas two αCD molecules sandwich the phenyl ring in a secondary-to-secondary rim orientation for the longer-chain derivatives. ßCD includes each compound to form 1:1 complexes, with their alkyl chains bent to varying degrees within the CD cavity. γCD includes two molecules of each compound to form 2:1 complexes, with both parallel and antiparallel orientations plausible. The study found that αCD is more suitable for overcoming the pharmaceutical drawbacks of PB and its shorter-chain derivative, while ßCD is better for the longer-chain derivatives.
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Ciclodextrinas , Ciclodextrinas/química , Química Farmacéutica/métodos , Fenilbutiratos , Preparaciones Farmacéuticas , SolubilidadRESUMEN
Hydrogen sulfide (H2S) induces acute and lethal toxicity at high concentrations. However, no specific antidotes for H2S poisoning have been approved. Liposomal methemoglobin (metHb@Lipo) was developed as an antidote for cyanide poisoning. As the toxic mechanism of H2S poisoning is the same as that of cyanide poisoning, metHb@Lipo could potentially be used as an antidote for H2S poisoning. In this study, we evaluated the antidotal efficacy of metHb@Lipo against H2S poisoning. Stopped-flow rapid-scan spectrophotometry clearly showed that metHb@Lipo scavenged H2S rapidly. Additionally, metHb@Lipo showed cytoprotective effects against H2S exposure in H9c2 cells by maintaining mitochondrial function. MetHb@Lipo treatment also improved the survival rate after H2S exposure in vivo, with the maintenance of cytochrome c oxidase activity and suppression of metabolic acidosis. Moreover, metHb@Lipo therapy maintained significant antidotal efficacy even after 1-year-storage at 4-37 °C. In conclusion, metHb@Lipo is a candidate antidote for H2S poisoning.
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Sulfuro de Hidrógeno , Intoxicación , Antídotos/farmacología , Antídotos/uso terapéutico , Cianuros , Humanos , Sulfuro de Hidrógeno/metabolismo , Metahemoglobina/metabolismo , Metahemoglobina/farmacología , Intoxicación/tratamiento farmacológicoRESUMEN
Nateglinide (NAT) is used to treat diabetes, stimulating pancreatic islet ß-cells with residual insulin secretory capacity to increase insulin secretion. NAT has been reported to bind to human serum albumin (HSA), but the detail is still unclear. In the current study, we investigated the location and the affinity for the binding of NAT to HSA. Quantitative analysis data from the ultrafiltration experiment indicated that NAT binds strongly to a primary site on HSA with a high affinity. The presence of diazepam (DZP) or ibuprofen (IB), the specific site II ligands of HSA, decreased the binding constants of NAT respectively, without the significant changes in the number of binding sites. Whereas warfarin (WF), a site I specific ligand, did not affect the binding of NAT. Fluorescent replacement experiment showed that NAT replaced dansylsarcosine (DNSS), a site II probe of HSA, but not WF. An increasing level of myristate and uremic toxins, indoxyl sulphate (IS), indoxyl acetate (IA) and p-cresyl sulphate (PCS), during renal disease significantly increased the concentration of unbound NAT. These findings suggest that NAT specifically binds to site II of HSA and the binding capacity and pharmacokinetics of NAT change in renal diseases.
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Secretagogos , Albúmina Sérica Humana , Ácidos Grasos , Humanos , Insulina , Insulina Regular Humana , Ligandos , Nateglinida , Albúmina Sérica/metabolismo , Tóxinas Urémicas , WarfarinaRESUMEN
The aim of this study was to investigate the beneficial effects of sacran, a sulfated polysaccharide, on renal damage and intestinal microflora, in 5/6 nephrectomy rats as a model for chronic kidney disease (CKD). 5/6 Nephrectomy rats were divided into sacran treated and non-treated groups and examined for lethality after 4 weeks. The 5/6 nephrectomy rats were also divided into three groups: sacran treated, non-treated and AST-120 treated groups, and treated orally in a concentration-dependent manner for 4 weeks. Renal function was estimated by biochemical and histopathological analyses. Metagenomic analysis of feces from each group after 4 weeks was also performed and changes in intestinal microflora were compared. The administration of sacran to CKD rats at ≥19 mg/d increased their survival. In addition, the sacran-treated group improved CKD-related parameters in a concentration-dependent manner, and the inhibitory effect of 40 mg/d of sacran was comparable to that of AST-120. The changes in the intestinal microflora of the sacran treated group were positively correlated with an increase in the number of Lactobacillus species, which are known to be rich in beneficial bacteria, and the increment of this beneficial bacteria was negatively correlated with the concentration of indoxyl sulfate, a uremic toxin, in plasma. These results strongly suggest that the oral administration of sacran could contribute to the stabilization of intestinal microflora in CKD rats and to the reduction of oxidative stress as well as the inhibition of progression of CKD.
Asunto(s)
Microbioma Gastrointestinal , Insuficiencia Renal Crónica , Animales , Femenino , Humanos , Masculino , Polisacáridos/farmacología , Polisacáridos/uso terapéutico , Ratas , Insuficiencia Renal Crónica/tratamiento farmacológico , Sulfatos/uso terapéuticoRESUMEN
Albumin, the most abundant protein in human serum, is applied to various diseases as a drug delivery carrier because of its superior blood retention, high biocompatibility, and a wide variety of drug binding abilities. Albumin is known to distribute widely in the blood and various interstitial fluids and organs. Different albumin receptors skillfully regulate the distribution characteristics of albumin in the body. Albumin receptors are a group of diverse proteins, such as FcRn, gp60, gp18, megalin, cubilin, SPARC, and CD36. Their tissue distributions in vivo are unique, with different albumin's recognition sites. Therefore, the distribution of albumin in vivo is ingeniously controlled by these multiple albumin receptors. Reevaluation of these albumin receptors opens up new possibilities for applying albumin as a drug delivery carrier. If the tissue distributions of albumin receptors were known and the albumin recognition site of the receptor was identified, organ-specific active targeting would be possible. In this review, we would like to scrutinize what is currently known and share information to develop next-generation albumin carriers that focus on interactions with albumin receptors.
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Albúminas , Excipientes , Sistemas de Liberación de Medicamentos , Humanos , Receptores de Albúmina/metabolismo , Distribución TisularRESUMEN
BACKGROUND & AIMS: While certain nucleos(t)ide reverse transcriptase inhibitors (NRTIs) are efficacious in treating HBV infection, their effects are yet to be optimized and the emergence of NRTI-resistant HBV variants is an issue because of the requirement for lifelong treatment. The development of agents that more profoundly suppress wild-type and drug-resistant HBVs, and that have a long-acting effect, are crucial to improve patient outcomes. METHODS: Herein, we synthesized a novel long-acting 4'-modified NRTI termed E-CFCP. We tested its anti-HBV activity in vitro, before evaluating its anti-HBV activity in HBV-infected human-liver-chimeric mice (PXB-mice). E-CFCP's long-acting features and E-CFCP-triphosphate's interactions with the HBV reverse transcriptase (HBV-RT) were examined. RESULTS: E-CFCP potently blocked HBVWTD1 production (IC50qPCR_cell=1.8 nM) in HepG2.2.15 cells and HBVWTC2 (IC50SB_cell=0.7 nM), entecavir (ETV)-resistant HBVETV-RL180M/S202G/M204V (IC50SB_cell=77.5 nM), and adefovir-resistant HBVADV-RA181T/N236T production (IC50SB_cell=14.1 nM) in Huh7 cells. E-CFCP profoundly inhibited intracellular HBV DNA production to below the detection limit, but ETV and tenofovir alafenamide (TAF) failed to do so. E-CFCP also showed less toxicity than ETV and TAF. E-CFCP better penetrated hepatocytes and was better tri-phosphorylated; E-CFCP-triphosphate persisted intracellularly for longer than ETV-triphosphate. Once-daily peroral E-CFCP administration over 2 weeks (0.02~0.2 mg/kg/day) reduced HBVWTC2-viremia by 2-3 logs in PXB-mice without significant toxicities and the reduction persisted over 1-3 weeks following treatment cessation, suggesting once-weekly dosing capabilities. E-CFCP also reduced HBVETV-RL180M/S202G/M204V-viremia by 2 logs over 2 weeks, while ETV completely failed to reduce HBVETV-RL180M/S202G/M204V-viremia. E-CFCP's 4'-cyano and fluorine interact with both HBVWT-RT and HBVETV-RL180M/S202G-M204 -RT via Van der Waals and polar forces, being important for E-CFCP-triphosphate's interactions and anti-HBV potency. CONCLUSION: E-CFCP represents the first reported potential long-acting NRTI with potent activity against wild-type and treatment-resistant HBV. LAY SUMMARY: Although there are currently effective treatment options for HBV, treatment-resistant variants and the need for lifelong therapy pose a significant challenge. Therefore, the development of new treatment options is crucial to improve outcomes and quality of life. Herein, we report preclinical evidence showing that the anti-HBV agent, E-CFCP, has potent activity against wild-type and treatment-resistant variants. In addition, once-weekly oral dosing may be possible, which is preferrable to the current daily dosing regimens.
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Desarrollo de Medicamentos/métodos , Farmacorresistencia Viral/efectos de los fármacos , Virus de la Hepatitis B , Hepatitis B , Inhibidores de la Transcriptasa Inversa/farmacología , Animales , Preparaciones de Acción Retardada/farmacología , Modelos Animales de Enfermedad , Vías de Administración de Medicamentos , Esquema de Medicación , Hepatitis B/tratamiento farmacológico , Hepatitis B/virología , Virus de la Hepatitis B/efectos de los fármacos , Virus de la Hepatitis B/fisiología , Humanos , Ratones , ADN Polimerasa Dirigida por ARN/metabolismo , TiempoRESUMEN
Benzbromarone has been used for the treatment of gout for more than 30 years. Although it shows a high level of binding to plasma proteins (>99%), our knowledge of this binding is not sufficiently extensive to permit us to understand its pharmacokinetics and pharmacodynamics. To address this issue in more detail, we characterized the binding of benzbromarone to human serum albumin (HSA), the most abundant protein in plasma. Equilibrium dialysis and circular dichroism findings indicated that benzbromarone binds strongly to one primary as well as to multiple secondary sites on HSA and that the bromine atoms of benzbromarone play important roles in this high affinity binding. An X-ray crystallographic study revealed that benzbromarone molecules bind to hydrophobic pockets within subdomains IB, IIA, and IIIA. Inhibition experiments using site specific ligands (subdomain IB; fusidic acid, IIA; warfarin, IIIA; diazepam) indicated that the primary and secondary binding sites that benzbromarone binds to are within subdomains IIIA and IB/IIA, respectively. Lastly, a study of the effect of fatty acids on the benzbromarone-HSA interaction suggested that benzbromarone, when displaced from subdomain IIIA by sodium oleate, could transfer to subdomains IB or IIA. Thus, these data will permit more relevant assessments of the displacement interactions of benzbromarone especially in cases of co-administered drugs or endogenous compounds that also bind to subdomain IIIA. In addition, the findings presented herein will also be useful for designing drug combination therapy in which pharmacokinetic and pharmacodynamic performance need to be controlled.
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Benzbromarona/metabolismo , Sitios de Unión/fisiología , Dominios Proteicos/fisiología , Albúmina Sérica Humana/metabolismo , Dicroismo Circular/métodos , Cristalografía por Rayos X/métodos , Ácidos Grasos/metabolismo , Humanos , Ligandos , Unión Proteica/fisiologíaRESUMEN
Nafamostat mesilate (NFM) is used as an anticoagulant during hemodialysis in patients who have had complications due to hemorrhages. The formation of precipitates, which could lead to the interruption of hemodialysis has been reported when NFM is infused into blood during hemodialysis. We report herein on an examination of possible factors that could cause this. The effects of electrolytes such as phosphates, citrates or succinates on the formation of precipitates were examined by mixing NFM with aqueous solutions or plasma that contained these electrolytes. The formation of precipitates was observed in all electrolyte solutions when higher concentrations of NFM were mixed at around physiological pH. In the case of plasma, precipitates were observed when solutions containing higher concentrations of NFM were mixed with plasma that contained phosphate and citrate. In addition, the formation of precipitates under dynamic conditions where NFM was infused into flowing electrolyte solutions was also evaluated. The data suggested that such precipitates might be formed and disrupt the blood flow and/or an NFM infusion when NFM is infused into blood flowing in the hemodialysis circuit. The findings presented herein suggest the serum levels of anionic electrolytes (e.g., phosphate), the type of excipients present in pharmaceutical products (e.g., succinic acid or citric acid), the concentration of NFM used for the infusion or the rates of NFM infusion and blood flow are all factors that could affect precipitate formation during NFM infusions for hemodialysis.
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Anticoagulantes/administración & dosificación , Benzamidinas/administración & dosificación , Soluciones para Diálisis/química , Guanidinas/administración & dosificación , Diálisis Renal/efectos adversos , Aniones/sangre , Aniones/química , Anticoagulantes/química , Benzamidinas/química , Electrólitos/sangre , Electrólitos/química , Guanidinas/química , Hemorragia/tratamiento farmacológico , Hemorragia/etiología , Humanos , Plasma/química , SolubilidadRESUMEN
We recently reported that aripiprazole (ARP), an antipsychotic drug, binds strongly to human serum albumin (HSA), the major drug binding protein in serum. It is known that uremic toxins that accumulate during renal disease affect the interaction between HSA and drug binding. In this study, the issue of how uremic toxins (indoxyl sulfate, indole acetic acid and p-cresyl sulfate) affect the binding of ARP to HSA was investigated. Equilibrium dialysis experiments revealed that all uremic toxins inhibited the binding of ARP to HSA although the inhibitory effects differed, depending on the specific uremic toxin. The potency of inhibition can be partially explained by the affinities of uremic toxins to HSA. Fluorescence displacement experiments suggested that ARP as well as all uremic toxins bind to site II of HSA. The inhibitory effects of the toxins on the binding of ARP for the drugs binding to the diazepam subsite are significantly larger, comparing with those for binding to arylpropionic acids subsite. Interestingly, induced circular dichroism (CD) spectra indicated that the spatial orientation of p-cresyl sulfate in the binding pocket is different from that for indoxyl sulfate and indole acetic acid. The limited findings obtained herein are important data in considering the effects of uremic toxins on the pharmacokinetics of ARP and the drugs that bind to site II on HSA, particularly drugs binding to diazepam binding site in site II.
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Antipsicóticos/farmacología , Aripiprazol/farmacología , Cresoles/farmacología , Indicán/farmacología , Ácidos Indolacéticos/farmacología , Albúmina Sérica Humana/metabolismo , Ésteres del Ácido Sulfúrico/farmacología , Sitios de Unión , Humanos , Ácido Oléico/farmacología , Unión Proteica , UremiaRESUMEN
INTRODUCTION: The novel nucleoside analog, 4'-cyano-2'-deoxyguanosine (CdG), possesses inhibitory activity against both the wild-type and resistant hepatitis B virus. Since the dosage of the currently available nucleoside analog preparations needs to be adjusted, depending on renal function, we investigated the effect of renal dysfunction on the pharmacokinetics of CdG in a rat model of chronic kidney disease (CKD). METHODS: CKD model rats were either intravenously or orally administered CdG at a dose of 1 mg/kg. The concentration of CdG in plasma, organs (liver and kidney) and urine samples were determined by means of a UPLC system interfaced with a TOF-MS system. RESULTS: Following intravenous administration, the plasma retention of CdG was prolonged in CKD model rats compared to healthy rats. In addition, the clearance of CdG was well correlated with plasma creatinine levels in CKD model rats. Similar to the results for intravenous administration, the plasma concentration profiles of CdG after oral administration were also found to be much higher in CKD model rats than in healthy rats. However, the results for the organ distribution and urinary excretion of CdG, the profiles of which were similar to that of healthy rats, indicated that CdG did not accumulate to a significant extent in the body. CONCLUSION: The extent of renal dysfunction has a direct influence on the pharmacokinetics (plasma retention) of CdG without a significant accumulation, indicating that the dosage of CdG will be dependent on the extent of renal function. .
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Nucleósidos , Insuficiencia Renal Crónica , Animales , Desoxiguanosina/análogos & derivados , Virus de la Hepatitis B , Ratas , Insuficiencia Renal Crónica/tratamiento farmacológicoRESUMEN
Albumin is widely conserved from vertebrates to invertebrates, and nature of mammalian albumins permit them to bind various endogenous ligands and drugs in the blood. It is known that at least two major ligand binding sites are present on the albumin molecule, which are referred to as Site I and Site II. These binding sites are thought to be almost completely conserved among mammals, even though the degree of binding to these sites are different depending on the physical and chemical properties of drugs and differences in the microenvironment in the binding pockets. In addition, the binding sites for medium and long-chain fatty acids are also well conserved among mammals, and it is considered that there are at least seven binding sites, including Site I and Site II. These bindings properties of albumin in the blood are also widely known to be important for transporting drugs and fatty acids to various tissues. It can therefore be concluded that albumin is one of the most important serum proteins for various ligands, and information on human albumin can be very useful in predicting the ligand binding properties of the albumin of other vertebrates.
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Ácidos Grasos/metabolismo , Preparaciones Farmacéuticas/metabolismo , Albúmina Sérica/metabolismo , Animales , Sitios de Unión , Ácidos Grasos/química , Humanos , Preparaciones Farmacéuticas/química , Unión Proteica , Albúmina Sérica/químicaRESUMEN
Many victims, after being extricated from a collapsed building as the result of a disaster, suffer from disaster nephrology, a term that is referred to as the crush syndrome (CS). Recommended treatments, which include dialysis or the continuous administration of massive amounts of fluid are not usually easy in cases of such mass natural disasters. In the present study, we examined the therapeutic performance of a biomimetic carbon monoxide (CO) delivery system, CO-enriched red blood cells (CO-RBCs), on experimental animal models of an acute kidney injury (AKI) induced by traumatic and nontraumatic rhabdomyolysis, including CS and rhabdomyolysis with massive hemorrhage shock. A single CO-RBC treatment was found to effectively suppress the pathogenesis of AKI with the mortality in these model rats being improved. In addition, in further studies using glycerol-induced rhabdomyolysis model rats, the pathogenesis of which is similar to that for the CS, AKI and mortality were also reduced as the result of a CO-RBC treatment. Furthermore, CO-RBCs were found to have renoprotective effects via the suppression of subsequent heme protein-associated renal oxidative injury; the oxidation of myoglobin in the kidneys, the generation of reactive oxygen species by free heme produced from degraded-cytochrome P450 and hemoglobin-associated renal injury. Because CO-RBCs can be prepared and used at both hospitals and at a disaster site, these findings suggest that CO-RBCs have the potential for use as a novel cell therapy against both nontraumatic and traumatic rhabdomyolysis including CS-induced AKI. SIGNIFICANCE STATEMENT: After mass natural and man-made disasters, people who are trapped in collapsed buildings are in danger of acute kidney injury (AKI), including crush syndrome (CS)-related AKI. This paper reports that carbon monoxide-enriched red blood cells (CO-RBCs), which can be prepared at both hospitals and disaster sites, dramatically suppressed the pathogenesis of CS-related AKI, thus improving mortality via suppressing heme protein-associated renal injuries. CO-RBCs have the potential for serving as a practical therapeutic agent against disaster nephrology associated with the CS.
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Lesión Renal Aguda/tratamiento farmacológico , Monóxido de Carbono/uso terapéutico , Síndrome de Aplastamiento/complicaciones , Eritrocitos/química , Riñón/efectos de los fármacos , Rabdomiólisis/complicaciones , Lesión Renal Aguda/etiología , Animales , Apoptosis/efectos de los fármacos , Monóxido de Carbono/administración & dosificación , Modelos Animales de Enfermedad , Sistemas de Liberación de Medicamentos , Riñón/metabolismo , Riñón/patología , Células LLC-PK1 , Estrés Oxidativo/efectos de los fármacos , Ratas Sprague-Dawley , Análisis de Supervivencia , PorcinosRESUMEN
Deposition of amyloid protein, particularly Aß1-42 , is a major contributor to the onset of Alzheimer's disease (AD). However, almost no deposition of Aß in the peripheral tissues could be found. Human serum albumin (HSA), the most abundant protein in the blood, has been reported to inhibit amyloid formation through binding Aß, which is believed to play an important role in the peripheral clearance of Aß. We identified the Aß binding site on HSA and developed HSA mutants with high binding capacities for Aß using a phage display method. HSA fragment 187-385 (Domain II) was found to exhibit the highest binding capacity for Aß compared with the other two HSA fragments. To elucidate the sequence that forms the binding site for Aß on Domain II, a random screening of Domain II display phage biopanning was constructed. A number of mutants with higher Aß binding capacities than the wild type were identified. These mutants exhibited stronger scavenging abilities than the wild type, as revealed via in vitro equilibrium dialysis of Aß experiments. These findings provide useful basic data for developing a safer alternative therapy than Aß vaccines and for application in plasma exchange as well as extracorporeal dialysis.
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Péptidos beta-Amiloides/metabolismo , Biblioteca de Péptidos , Albúmina Sérica Humana/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Sitios de Unión , Bioprospección , Humanos , Mutación , Dominios Proteicos , Albúmina Sérica Humana/genéticaRESUMEN
A nucleoside analog, 4'-cyano-2'-deoxyguanosine (CdG), which was developed as an inhibitor of the chronic hepatitis B virus (HBV), exhibited a superior antiviral activity against both wild-type and drugs-resistant HBV to marketed nucleoside analogs. In addition to previous pharmacokinetic studies of CdG in healthy rats, this study reports on an evaluation of the pharmacokinetic characteristics of CdG in a rat model of viral liver injury (VLI) induced by treatment with concanavalin A. Following an intravenous administration of CdG at a dose of 1 mg/kg, the plasma concentration profile of CdG in VLI model rats was found to be similar to that of healthy rats with no significant difference in kinetic parameters. However, when CdG was orally administered at a dose of 1 mg/kg, the maximum blood concentration was much lower in VLI model rats than in healthy rats. Interestingly, the amount of residual food in the stomachs in VLI model rats was significantly larger than that in healthy rats, indicating that the adsorption of CdG in the gastrointestinal tract was inhibited in the presence of food as well as other marketed nucleoside analogs. As observed in healthy rats, CdG was largely distributed to the liver compared to the kidney in the VLI model. These results suggest that liver pathology has only a minor effect on the pharmacokinetic properties of CdG, but the influence of food on CdG absorption needs to be considered.
Asunto(s)
Antivirales/farmacocinética , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Desoxiguanosina/análogos & derivados , Hepatitis B Crónica/tratamiento farmacológico , Hígado/patología , Administración Intravenosa , Animales , Antivirales/administración & dosificación , Enfermedad Hepática Inducida por Sustancias y Drogas/sangre , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Concanavalina A/administración & dosificación , Concanavalina A/toxicidad , Desoxiguanosina/administración & dosificación , Desoxiguanosina/farmacocinética , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Interacciones Alimento-Droga , Absorción Gastrointestinal , Hepatitis B Crónica/patología , Humanos , Hígado/efectos de los fármacos , Hígado/virología , Masculino , RatasRESUMEN
Aripiprazole (ARP) is one of antipsychotics and binds to human serum albumin (HSA) with a high affinity. In this study, we investigated the binding characteristics of ARP to oxidized HSA as observed in chronic disease conditions. Oxidized HSAs were prepared using chloramine-T (CT-HSA) or metal-catalyzed oxidation system (MCO-HSA) in vitro, respectively. An increase in the carbonyl content was confirmed in oxidized HSAs. From the results of circular dichroism (CD) and tryptophan fluorescence spectra, no significant structural change of oxidized HSAs was observed. These results indicate that prepared HSAs are mildly oxidized and well reflects the status of HSA during chronic diseases. However, oxidized HSAs were observed to have a significant decrease in binding to ARP. The results of the induced CD spectrum suggested that ARP bound to oxidized HSAs with a similar orientation. These results suggest that oxidation of HSA during chronic disease state significantly affected the microenvironment of the binding site for ARP and binding capacity of HSA to ARP.
Asunto(s)
Antipsicóticos/química , Aripiprazol/química , Albúmina Sérica Humana/química , Cloraminas/química , Dicroismo Circular , Oxidación-Reducción , Carbonilación Proteica , Espectrometría de Fluorescencia , Compuestos de Tosilo/química , TriptófanoRESUMEN
Kupffer cells are a major producer of reactive oxygen species and have been implicated in the development of liver fibrosis during chronic hepatitis in non-alcoholic steatohepatitis (NASH) and alcoholic steatohepatitis (ASH). We recently reported on the development of a polythiolated and mannosylated human serum albumin (SH-Man-HSA) that functions as a Kupffer cell-targeting nanoantioxidant. In this material, the albumin is mannosylated, which permits it to be taken up by mannose receptor C type 1 expressed on Kupffer cells, and is also polythiolated to have antioxidant activity. To clarify the anti-fibrotic property of this nanoantioxidant, we repeatedly administered SH-Man-HSA to a liver fibrosis mouse model that was induced by the repeated treatment of the concanavalin-A, which mimics the liver fibrosis observed in NASH and ASH. SH-Man-HSA dramatically improved the survival rate and suppressed liver fibrosis in the experimental model. In addition, SH-Man-HSA suppressed hepatic oxidative stress levels, thereby decreasing the numbers of apoptotic cells. In contrast, N-acetylcysteine, which contains the same thiol content as the SH-Man-HSA, failed to show a substantial therapeutic effect in these mice. The expression levels of inflammatory genes including epidermal growth factor module-containing mucin-like receptor (Emr-1/F4/80), Toll-like receptor-4 (TLR-4), high mobility group box-1 (HMGB-1), CC chemokine ligand-5 (CCL-5), tumor necrosis factor-α (TNF-α), CCL-2, interleukin-6 (IL-6), and IL-1ß, as well as fibrotic (α-smooth muscle actin (α-SMA), transforming growth factor-ß (TGF-ß), and Snail) and extracellular matrix genes (collagen, type Iα2 (Col1α2), matrix metalloproteinase-9 (MMP-9), and tissue inhibitor of metalloproteinase 1 (TIMP-1)), showed some decreasing trends by the SH-Man-HSA administration. These findings suggest that the repeated administration of the Kupffer cell-targeting nanoantioxidant, SH-Man-HSA, ameliorates liver fibrosis in mice by suppressing the level of oxidative stress and a portion of the inflammation, and has a potential therapeutic effect against NASH and ASH.