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Showing papers on "Serum albumin published in 2018"


Journal ArticleDOI
TL;DR: Serum albumin, a natural ligand carrier that is highly concentrated and long-circulating in the blood, has shown remarkable promise as a carrier for anti-cancer agents.

255 citations


Journal ArticleDOI
TL;DR: The purpose of this review is to provide an overview of the physiological properties of serum albumin, as well as prevalence, causes, prognostic value and potential contribution to the disease emergence and progression of hypoalbuminemia, and the resulting clinical implications.

195 citations


Journal ArticleDOI
TL;DR: Having excluded potential confounding effect of exogenous albumin administration, low serum albumin levels are associated with an increased risk of death in patients with severe sepsis.
Abstract: Background:The prognostic significance of serum albumin levels in patients with sepsis has previously been reported; however, these studies have not excluded the potential confounding effect of exo...

100 citations


Journal ArticleDOI
TL;DR: The fluorescence, UV- absorption, three dimensional fluorescence and FT-IR data showed conformational changes occurred in BSA after interaction with neratinib, suggesting an instable complex formation at high temperature.
Abstract: Binding of therapeutic agents to plasma proteins, particularly to serum albumin, provides valuable information in the drug development. This study was designed to evaluate the binding interaction of neratinib with bovine serum albumin (BSA). Neratinib blocks HER2 signaling and is effective in trastuzumab-resistant breast cancer treatment. Spectrofluorometric, UV spectrophotometric, and fourier transform infrared (FT-IR) and molecular docking experiments were performed to study this interaction. The fluorescence of BSA is attributed to the presence of tryptophan (Trp) residues. The fluorescence of BSA in presence of neratinib was studied using the excitation wavelength of 280 nm and the emission was measured at 300-500 nm at three different temperatures. Neratinib quenched the BSA intrinsic fluorescence by static mechanism. A complex formation occurred due to the interaction leading to BSA absorption shift. The fluorescence, UV- absorption, three dimensional fluorescence and FT-IR data showed conformational changes occurred in BSA after interaction with neratinib. The binding constant values decreased as the temperature increased suggesting an instable complex formation at high temperature. Site I (sub-domain IIA) was observed as the principal binding site for neratinib. Hydrogen bonding and Van der Waals forces were suggested to be involved in the BSA-neratinib interaction due to the negative values of entropy and enthalpy changes.

83 citations


Journal ArticleDOI
TL;DR: The sensing aptitude of probe L to detect HSA in body fluid and an artificial-urine sample has been demonstrated and the specific binding of L with HSA led to the disassembly of the self-assembled nanoaggregates of L, which was corroborated by dynamic-light-scattering (DLS) and transmission-electron-microscopy (TEM) analysis.
Abstract: Two cyanine-based fluorescent probes, (E)-2-(4-(diethylamino)-2-hydroxystyryl)-3-ethyl-1,1-dimethyl-1H-benzo[e]indol-3-ium iodide (L) and (E)-3-ethyl-1,1-dimethyl-2-(4-nitrostyryl)-1H-benzo[e]indol-3-ium iodide (L1), have been designed and synthesized. Of these two probes, the twisted-intramolecular-charge-transfer (TICT)-based probe, L, can preferentially self-assemble to form nanoaggregates. L displayed a selective turn-on fluorescence response toward human and bovine serum albumin (HSA and BSA) in ∼100% aqueous PBS medium, which is noticeable with the naked eye, whereas L1 failed to sense these albumin proteins. The selective turn-on fluorescence response of L toward HSA and BSA can be attributed to the selective binding of probe L with HSA and BSA without its interfering with known drug-binding sites. The specific binding of L with HSA led to the disassembly of the self-assembled nanoaggregates of L, which was corroborated by dynamic-light-scattering (DLS) and transmission-electron-microscopy (TEM) an...

67 citations


Journal ArticleDOI
TL;DR: A styryl based fluorophore for serum albumin detection is reported, which displays an exceptional turn-on emission enhancement of ∼500 fold, the highest reported so far in the near-infrared region, and more importantly enables quantification of albumin in the complex serum matrix.

66 citations


Journal ArticleDOI
TL;DR: The coupling of a targeted peptide, a therapeutic radionuclide, and the EB‑based albumin binding provides for effective treatment of SSTR2-containing tumors.
Abstract: Purpose: Radionuclide therapy directed against tumors that express somatostatin receptors (SSTRs) has proven effective for the treatment of advanced, low- to intermediate-grade neuroendocrine tumors in the clinic. In clinical usage, somatostatin peptide-based analogs, labeled with therapeutic radionuclides, provide an overall response rate of about 30%, despite the high cumulative activity injected per patient. We set out to improve the effectiveness of somatostatin radiotherapy by preparing a chemical analog that would clear more slowly through the urinary tract and, concomitantly, have increased blood circulation half-life and higher targeted accumulation in the tumors. Experimental Design: We conjugated a common, clinically-used SST peptide derivative, DOTA-octreotate, to an Evans blue analog (EB), which reversibly binds to circulating serum albumin. The resulting molecule was used to chelate 86Y and 90Y, a diagnostic and a therapeutic radionuclide, respectively. The imaging capabilities and the radiotherapeutic efficacy of the resulting radioligand was evaluated in HCT116/SSTR2, HCT116, and AR42J cell lines that express differing levels of SST2 receptors. Results: The synthesized radiopharmaceutical retained affinity and specificity to SSTR2. The new molecule also retained the high internalization rate of DOTA-octreotate, and therefore, showed significantly higher accumulation in SSTR2-positive tumors. Labeling of our novel EB-octreotate derivative with the therapeutic, pure beta emitter, 90Y, resulted in improved tumor response and survival rates of mice bearing SSTR2 xenografts and had long term efficacy when compared to DOTA-octreotate itself. Conclusions: The coupling of a targeted peptide, a therapeutic radionuclide, and the EB‑based albumin binding provides for effective treatment of SSTR2-containing tumors.

64 citations


Journal ArticleDOI
TL;DR: Lower serum albumin levels are strongly and independently associated with kidney function decline in elders, independent of clinical risk factors, urine albumin and measured inflammatory markers.
Abstract: Background Previous studies in HIV-infected individuals have demonstrated serum albumin to be strongly associated with kidney function decline, independent of urine albumin and inflammatory markers. Lower serum albumin concentrations may be an under-appreciated risk factor for kidney function decline in elders. Methods We performed a cohort analysis in the Health Aging and Body Composition Study, a cohort of well-functioning, bi-racial, community-dwelling elders between the age of 70 and 79 years. We examined the associations of serum albumin concentration with longitudinal kidney function decline by estimated glomerular filtration rate (eGFR). Outcomes included linear eGFR decline, rapid kidney function decline defined as >30% decrease in eGFR, defined as a final eGFR 60 mL/min/1.73 m2 at baseline. Cystatin C-based eGFR was calculated at baseline, Year 3 and Year 10. Results Mean age was 74 years, and mean eGFR was 73 mL/min/1.73 m2 at baseline. The mean rate of eGFR change was 1.81 mL/min/1.73 m2 per year. After multivariate adjustment, lower serum albumin concentrations were strongly and independently associated with kidney function decline (-0.11 mL/min/1.73 m2 per year for each standard deviation decrease serum albumin; -0.01 to - 0.20) with no attenuation after adjustment for urine albumin and inflammatory markers (-0.12, -0.03 to - 0.22). When divided into quartiles, serum albumin levels ≤3.80 g/dL were associated with increased odds of rapid kidney function decline (odds ratio 1.59; 1.12-2.26) and increased risk of incident chronic kidney disease (incident rate ratio 1.29; 1.03-1.62) relative to levels >4.21g/dL. Urine albumin to creatinine ratio (ACR) was also significantly and independently associated with kidney function decline (-0.08 mL/min/1.73 m2 per year for urine ACR >30 mg/g; -0.82 to - 0.13). Conclusions Lower serum albumin levels are strongly and independently associated with kidney function decline in elders, independent of clinical risk factors, urine albumin and measured inflammatory markers.

60 citations


Journal ArticleDOI
TL;DR: The result that S-homocysteinylation mediated increased surface hydrophobicity and ligand binding activity of HSA offer new insights into structural and functional alternation of serum albumins via S-thiolation.
Abstract: Human serum albumin (HSA) is the most abundant serum protein, contributing to the maintenance of redox balance in the extracellular fluids. One single free cysteine residue at position 34 is believed to be a target of oxidation. However, the molecular details and functions of oxidized HSAs remain obscure. Here we analyzed serum samples from normal subjects and hyperlipidemia patients and observed an enhanced S-thiolation of HSA in the hyperlipidemia patients as compared to the control individuals. Both cysteine and homocysteine were identified as the low molecular weight thiols bound to the HSAs. Intriguingly, S-thiolations were observed not only at Cys34, but also at multiple cysteine residues in the disulfide bonds of HSA. When the serum albumins from genetically modified mice that exhibit high levels of total homocysteine in serum were analyzed, we observed an enhanced S-homocysteinylation at multiple cysteine residues. In addition, the cysteine residues in the disulfide bonds were also thiolated in recombinant HSA that had been treated with the disulfide molecules. These findings and the result that S-homocysteinylation mediated increased surface hydrophobicity and ligand binding activity of HSA offer new insights into structural and functional alternation of serum albumins via S-thiolation.

55 citations


Journal ArticleDOI
TL;DR: Perylenediimide-benzimidazolium based fluorescent ‘turn-on’ probe BIM-PDI for selective detection of human serum albumin (HSA) and bovine serumalbumin (BSA) proteins shows absorption maxima at 500 nm and weak fluorescence centered at 577 nm.
Abstract: We report perylenediimide-benzimidazolium based fluorescent ‘turn-on’ probe BIM-PDI for selective detection of human serum albumin (HSA) and bovine serum albumin (BSA) proteins. In HEPES buffer (0.1% DMSO), BIM-PDI self-assembles into aggregates and shows absorption maxima at 500 nm and weak fluorescence centered at 577 nm. The addition of HSA or BSA (1 × 10−9–5 × 10−8 M) to the solution of BIM-PDI results in decrease in the emission intensity at 577 nm. However, further increase in concentration of HSA/BSA results in appearance of new blue shifted emission band at 540 nm. The minimum detection limit for HSA/BSA is 3.01 × 10−10 M at 577 nm and 4.2 × 10−8 M at 540 nm. On addition of BSA to the solution of BIM-PDI, the size of the aggregates decreased from 100 to 250 nm to

53 citations


Journal ArticleDOI
03 Dec 2018-Analyst
TL;DR: The data suggest that both the direct binding as well as interaction with the citrate ligands determine the interaction, yet to varying extent in the two very similar serum proteins, having implications for their use in bio-functionalization, and for the application of gold nanostructures in bioanalytics and medicine.
Abstract: The interaction of bovine serum albumin (BSA) and human serum albumin (HSA), sharing a sequence similarity of 77.5%, with gold nanoparticles of a size of ∼30 nm was investigated by surface-enhanced Raman scattering (SERS). The spectra provide information on those residues of the proteins in proximity of the nanoparticles. The SERS signals indicate an electrostatic interaction of both proteins with the citrate ligands at the nanoparticle surface via lysine residues. HSA, different from BSA also binds directly to the gold surface by particularly flexible protein segments that were identified by comparison of the vibrational bands with the known amino acid sequence of the molecule. The data suggest that both the direct binding as well as interaction with the citrate ligands determine the interaction, yet to varying extent in the two very similar serum proteins. This has implications for their use in bio-functionalization, and for the application of gold nanostructures in bioanalytics and medicine.

Journal ArticleDOI
TL;DR: It has become possible to prepare gels that have the desired nanoscopic and macroscopic properties, which can, in future, be tested for, e.g., drug delivery applications.
Abstract: We report extended pH- and temperature-induced preparation procedures and explore the materials and molecular properties of different types of hydrogels made from human and bovine serum albumin, the major transport protein in the blood of mammals. We describe the diverse range of properties of these hydrogels at three levels: (1) their viscoelastic (macroscopic) behavior, (2) protein secondary structure changes during the gelation process (via ATR-FTIR spectroscopy), and (3) the hydrogel fatty acid (FA) binding capacity and derive from this the generalized tertiary structure through CW EPR spectroscopy. We describe the possibility of preparing hydrogels from serum albumin under mild conditions such as low temperatures (notably below albumin's denaturation temperature) and neutral pH value. As such, the proteins retain most of their native secondary structure. We find that all the combined data indicate a two-stage gelation process that is studied in detail. We summarize these findings and the explored dependences of the gels on pH, temperature, concentration, and incubation time by proposing phase diagrams for both HSA and BSA gel-states. As such, it has become possible to prepare gels that have the desired nanoscopic and macroscopic properties, which can, in future, be tested for, e.g., drug delivery applications.

Journal ArticleDOI
TL;DR: The clinical features of the CLP mouse model were similar to those of human patients with sepsis, and Phenotypes of multiple organ dysfunction were found, including increased liver alanine aminotransferase and aspartate transaminase and significantly reduced total protein, globulin, and serum albumin.
Abstract: Objective Clinical sepsis-associated biomarkers were utilized in a cecal ligation and puncture (CLP) septic mouse model to provide a reference for investigating pathophysiological mechanisms and evaluating novel therapeutic interventions for sepsis. Methods Sepsis in mice was induced by CLP, and clinical biomarkers were evaluated (survival rate, blood physiological and biochemical indices, cytokines, hepatorenal function parameters, and blood coagulation). Results The mortality rate was >70%. The body temperature, blood pressure, and heart rate decreased within 48 h. Low lactic acid was found at 8 h. The CLP mice showed typical inflammatory symptoms with decreased white blood cells and procalcitonin and increased levels of soluble triggering receptor expressed on myeloid cells-1, interleukin (IL)-6, IL-10, tumor necrosis factor-α, macrophage inflammatory protein (MIP)-1α, MIP-1β, and MIP-2. The platelet count and activated partial thromboplastin time significantly decreased, and the prothrombin time and prothrombin time-international normalized ratio markedly increased. Phenotypes of multiple organ dysfunction were found in the CLP model, including increased liver alanine aminotransferase and aspartate transaminase; significantly reduced total protein, globulin, and serum albumin; increased blood urea nitrogen and creatinine; and decreased blood glucose. Conclusion The clinical features of the CLP mouse model were similar to those of human patients with sepsis.

Journal ArticleDOI
TL;DR: A lipid-conjugated floxuridine homomeric oligonucleotide (LFU20) that "hitchhikes" with endogenous serum albumin for cancer chemotherapy is reported, which accumulates in the tumor by the enhanced permeability and retention (EPR) effect and internalizes into the lysosomes of cancer cells.
Abstract: Automated attachment of chemotherapeutic drugs to oligonucleotides through phosphoramidite chemistry and DNA synthesis has emerged as a powerful technology in constructing structure-defined and payload-tunable oligonucleotide-drug conjugates. In practice, however, in vivo delivery of these oligonucleotides remains a challenge. Inspired by the systemic transport of hydrophobic payloads by serum albumin in nature, we report the development of a lipid-conjugated floxuridine homomeric oligonucleotide (LFU20) that "hitchhikes" with endogenous serum albumin for cancer chemotherapy. Upon intravenous injection, LFU20 immediately inserts into the hydrophobic cave of albumin to form an LFU20/albumin complex, which accumulates in the tumor by the enhanced permeability and retention (EPR) effect and internalizes into the lysosomes of cancer cells. After degradation, cytotoxic floxuridine monophosphate is released to inhibit cell proliferation.

Journal ArticleDOI
TL;DR: The obtained results from spectroscopic and electrochemistry experiments along with the computational studies suggest that DZN binds to residues located in subdomains IIA of HSA with binding constant about 1410.9 M−1 at 300 K.
Abstract: In the present research, the binding properties of diazinon (DZN), as an organophosphorus herbicide, to human serum albumin (HSA) were investigated using combination of spectroscopic, electrochemis

Journal ArticleDOI
TL;DR: CSF kappa and lambda combined with cKFLC can overcome challenges associated with performance, interpretation, and cost of traditional OCBs, reducing costs and maintaining sensitivity and specificity supporting MS diagnosis.
Abstract: Background Cerebrospinal fluid (CSF) used in immunoglobulin gamma (IgG) index testing and oligoclonal bands (OCBs) are common laboratory tests used in the diagnosis of multiple sclerosis. The measurement of CSF free light chains (FLC) could pose as an alternative to the labor-intensive isoelectric-focusing (IEF) gels used for OCBs. Methods A total of 325 residual paired CSF and serum specimens were obtained after physician-ordered OCB IEF testing. CSF kappa (cKFLC) and lambda FLC (cLFLC), albumin and total IgG were measured. Calculations were performed based on combinations of analytes: CSF sum of kappa and lambda ([cKFLC+cLFLC]), kappa-index (K-index) ([cKFLC/sKFLC]/[CSF albumin/serum albumin]), kappa intrathecal fraction (KFLCIF) {([cKFLC/sKFLC]-[0.9358×CSF albumin/serum albumin]^[0.6687×sKFLC]/cKFLC)} and IgG-index ([CSF IgG/CSF albumin]/[serum IgG/serum albumin]). Results Patients were categorized as: demyelination (n=67), autoimmunity (n=53), non-inflammatory (n=50), inflammation (n=38), degeneration (n=28), peripheral neuropathy (n=24), infection (n=13), cancer (n=11), neuromyelitis optica (n=10) and others (n=31). cKFLC measurement used alone at a cutoff of 0.0611 mg/dL showed >90% agreement to OCBs, similar or better performance than all other calculations, reducing the number of analytes and variables. When cases of demyelinating disease were reviewed, cKFLC measurements showed 86% clinical sensitivity/77% specificity. Conclusions cKFLC alone demonstrates comparable performance to OCBs along with increased sensitivity for demyelinating diseases. Replacing OCB with cKFLC would alleviate the need for serum and CSF IgG and albumin and calculated conversions. cKFLC can overcome challenges associated with performance, interpretation, and cost of traditional OCBs, reducing costs and maintaining sensitivity and specificity supporting MS diagnosis.

Journal ArticleDOI
TL;DR: A generation of immunotoxins containing albumin-binding domains that dramatically increase their half-life in the circulation and antitumor activity in mice are designed and produced.
Abstract: Recombinant immunotoxins (RITs) are chimeric proteins consisting of a Fv that binds to a cancer cell and a portion of a protein toxin. One of these, Moxetumomab pasudotox, was shown to be effective in treating patients with some leukemias, where the cells are readily accessible to the RIT. However, their short half-life limits their efficacy in solid tumors, because penetration into the tumors is slow. Albumin and agents bound to albumin have a long half-life in the circulation. To increase the time tumor cells are exposed to RITs, we have produced and evaluated variants that contain either an albumin-binding domain (ABD) from Streptococcus or single-domain antibodies from Llama. We have inserted these ABDs into RITs targeting mesothelin, between the Fv and the furin cleavage site. We find that these proteins can be produced in large amounts, are very cytotoxic to mesothelin-expressing cancer cell lines, and have a high affinity for human or mouse serum albumin. In mice, the RIT containing an ABD from Streptococcus has a longer half-life and higher antitumor activity than the other two. Its half-life in the circulation of mice ranges from 113 to 194 min compared with 13 min for an RIT with no ABD. Cell uptake studies show the RIT enters the target cell bound to serum albumin. We conclude that RITs with improved half-lives and antitumor activity should be evaluated for the treatment of cancer in humans.

Journal ArticleDOI
TL;DR: Results confirm that APO by its anti-inflammatory, antiapoptotic, and antioxidant effects can ameliorate GNT-induced nephrotoxicity.
Abstract: Gentamicin (GNT) is an aminoglycoside antibiotic used for treatment of serious infections, and the nephrotoxic adverse effect is one of the main therapeutic limitations. This study aimed to investigate the possible protective effect of apocynin (APO) on nephrotoxicity induced by GNT in rats. Twenty-four rats were allocated into three groups: control, GNT (100 mg/kg, intraperitoneally (i.p.)), and GNT plus APO (10 mg/kg, i.p.). All rats were killed at the end of the experiment, and then the blood, urine, and kidneys samples were taken. GNT-induced nephrotoxicity was manifested by a significant ( p < 0.05) increase in the weight of kidney, 24-h urine volume, renal somatic index (RSI), protein in urine, serum lactate dehydrogenase (LDH), creatinine (Cr), blood urea nitrogen (BUN), renal Fas ligand (CD95), nitric oxide (NO), and malondialdehyde (MDA). Furthermore, a significant reduction in body weight, creatinine clearance (CCr), serum albumin, renal superoxide dismutase (SOD), and glutathione activities were detected when compared with the control rats. APO ameliorated the nephrotoxic effect and oxidative damage caused by GNT by improving tissue morphology and significantly decreasing 24-h urine volume, RSI, serum Cr, LDH and BUN, protein in urine, and renal content of MDA, CD95, and NO. Additionally, APO caused a significant elevation in renal SOD activity and CCr when compared with the GNT group. These results confirm that APO by its anti-inflammatory, antiapoptotic, and antioxidant effects can ameliorate GNT-induced nephrotoxicity.


Journal ArticleDOI
TL;DR: Evidence is provided for a specific HSA-dependent self-defense mechanism against C difficile toxins and an explanation for the clinical correlation between CDI severity and hypoalbuminemia is provided.
Abstract: Background The pathogenic effects of Clostridium difficile are primarily attributable to the production of the large protein toxins (C difficile toxins [Tcd]) A (TcdA) and B (TcdB). These toxins monoglucosylate Rho GTPases in the cytosol of host cells, causing destruction of the actin cytoskeleton with cytotoxic effects. Low human serum albumin (HSA) levels indicate a higher risk of acquiring and developing a severe C difficile infection (CDI) and are associated with recurrent and fatal disease. Methods We used a combined approach based on docking simulation and biochemical analyses that were performed in vitro on purified proteins and in human epithelial colorectal adenocarcinoma cells (Caco-2), and in vivo on stem cell-derived human intestinal organoids and zebrafish embryos. Results Our results show that HSA specifically binds via its domain II to TcdA and TcdB and thereby induces their autoproteolytic cleavage at physiological concentrations. This process impairs toxin internalization into the host cells and reduces the toxin-dependent glucosylation of Rho proteins. Conclusions Our data provide evidence for a specific HSA-dependent self-defense mechanism against C difficile toxins and provide an explanation for the clinical correlation between CDI severity and hypoalbuminemia.

Journal ArticleDOI
TL;DR: The antileishmanial efficacy and the reduced toxicity become BSA nanoparticles containing AmB a potential candidate for treating cutaneous leishmaniasis.

Journal ArticleDOI
TL;DR: The pro-oxidative role of the RES-α-dicarbonyl conjugates should be further investigated to clarify whether this action leads to positive or harmful clinical consequences and the biological relevance of human protein carbonylation as a redox signaling mechanism and/or as a reflection of oxidative damage and disease should also be studied.

Journal ArticleDOI
TL;DR: In this paper, it was shown that swapping of two loops in domain I or the whole domain with the corresponding sequence in mouse albumin results in reduced binding to human FcRn.
Abstract: Albumin has a serum half-life of three weeks in humans and is utilized to extend the serum persistence of drugs that are genetically fused or conjugated directly to albumin or albumin-binding molecules. Responsible for the long half-life is FcRn that protects albumin from intracellular degradation. An in-depth understanding of how FcRn binds albumin across species is of importance for design and evaluation of albumin-based therapeutics. Albumin consists of three homologous domains where domain I and domain III of human albumin are crucial for binding to human FcRn. Here, we show that swapping of two loops in domain I or the whole domain with the corresponding sequence in mouse albumin results in reduced binding to human FcRn. In contrast, humanizing domain I of mouse albumin improves binding. We reveal that domain I of mouse albumin plays a minor role in the interaction with the mouse and human receptors, as domain III on its own binds with similar affinity as full-length mouse albumin. Further, we show that P573 in domain III of mouse albumin is required for strong receptor binding. Our study highlights distinct differences in structural requirements for the interactions between mouse and human albumin with their respective receptor, which should be taken into consideration in design of albumin-based drugs and evaluation in mouse models.

Journal ArticleDOI
TL;DR: Fusing an albumin binding domain (ABD) variant that basically derives from the streptococcal protein G and possesses a long-acting characteristic in serum albumin to the N-terminus of the HFn indicated that fusion with ABD will be a promising strategy to extend the half life for protein-based nanoparticles.

Journal ArticleDOI
TL;DR: This study shows that this kind of investigative approach, formerly applied to the interactions of metal-based drugs with small model proteins of MW 10-15 kDa, may now be extended with success to far larger proteins such as serum albumin (MW 66 kDa).
Abstract: The reactions of auranofin and three pseudohalide derivatives with bovine serum albumin were explored by ESI-Q-TOF mass spectrometry; a detailed molecular description of the resulting adducts is achieved revealing even subtle differences in reactivity within this series of gold(I) complexes. Our study shows that this kind of investigative approach, formerly applied to the interactions of metal-based drugs with small model proteins of MW 10-15 kDa, e.g., cytochrome c and lysozyme, may now be extended with success to far larger proteins such as serum albumin (MW 66 kDa).

Journal ArticleDOI
TL;DR: The knowledge about this novel HSA site will be important for drug depot development and for understanding drug-protein interaction, which are important prerequisites for modulation of drug pharmacokinetics.
Abstract: A single high-affinity fatty acid binding site in the important human transport protein serum albumin (HSA) is identified and characterized using an NBD (7-nitrobenz-2-oxa-1,3-diazol-4-yl)-C12 fatty acid. This ligand exhibits a 1:1 binding stoichiometry in its HSA complex with high site-specificity. The complex dissociation constant is determined by titration experiments as well as radioactive equilibrium dialysis. Competition experiments with the known HSA-binding drugs warfarin and ibuprofen confirm the new binding site to be different from Sudlow-sites I and II. These binding studies are extended to other albumin binders and fatty acid derivatives. Furthermore an X-ray crystal structure allows locating the binding site in HSA subdomain IIA. The knowledge about this novel HSA site will be important for drug depot development and for understanding drug-protein interaction, which are important prerequisites for modulation of drug pharmacokinetics.

Journal ArticleDOI
21 Jun 2018-PLOS ONE
TL;DR: Admission serum albumin levels ≤2.4 and ≥4.5 mg/dL were associated with an increased risk of HAKI with odds ratios of 1.52 ( 95% CI 1.18–1.94) and 2.16 (95%CI 1.74–2.69) after adjusting for potential confounders.
Abstract: BACKGROUND While an association between hypoalbuminemia and increased risk of acute kidney injury (AKI) is well-established, the risk of AKI development and its severity among patients with elevated serum albumin is unclear. The aim of this study was to evaluate the risk of AKI in hospitalized patients stratified by various admission serum albumin levels. METHODS This single-center retrospective study was conducted at a tertiary referral hospital. All adult hospitalized patients who had admission albumin levels available between January 2009 and December 2013 were enrolled. Admission albumin was categorized based on its distribution into six groups (≤2.4, 2.5-2.9, 3.0-3.4, 3.5-3.9, 4.0-4.4, and ≥4.5 mg/dL). The primary outcome was the incidence of hospital-acquired AKI (HAKI). Logistic regression analysis was performed to obtain the odds ratio of AKI for various admission albumin strata using the albumin 3.5 to 3.9 mg/dL (lowest incidence of AKI) as the reference group. RESULTS Of the total 9,552 studied patients, HAKI occurred in 1,556 (16.3%) patients. The incidence of HAKI among patients with admission albumin ≤2.4, 2.5-2.9, 3.0-3.4, 3.5-3.9, 4.0-4.4, and ≥4.5 mg/dL was 18.3%, 14.3%, 15.5%, 14.2%, 16.7%, and 26.0%, respectively. After adjusting for potential confounders, admission serum albumin levels ≤2.4 and ≥4.5 mg/dL were associated with an increased risk of HAKI with odds ratios of 1.52 (95% CI 1.18-1.94) and 2.16 (95% CI 1.74-2.69), respectively. While stage 1 HAKI was significantly more frequent among patients with admission albumin ≥4.5 mg/dL (23.0% vs. 11.6%, P<0.001), incidence of stage 3 HAKI was higher in those with albumin ≤2.4 mg/dL (2.8% vs 0.3%, P<0.001). CONCLUSION Admission serum albumin levels ≤2.4 and ≥4.5 mg/dL were associated with an increased risk for HAKI. Patients with admission albumin ≥4.5 mg/dL had HAKI with a lower intensity when compared with those who had admission albumin levels ≤2.4 mg/dL.

Journal ArticleDOI
TL;DR: Neither serum albumin level nor serum prealbumin level trends correlate with calorie or protein deficits and should not be used to assess adequacy of nutrition delivery in the ICU.
Abstract: BACKGROUND Serum albumin and prealbumin levels, may be more strongly associated with inflammation than with nutrient delivery. Their predictive value has not been extensively described in surgical intensive care unit (ICU) patients. METHODS We analyzed a registry of adult surgical ICU patients receiving enteral nutrition. Subjects with at least 1 serum albumin, prealbumin, or C-reactive protein (CRP) level were included. Demographic, nutrition, and clinical outcome data were collected. RESULTS A total 252 subjects were included. A subset had serial measurements: albumin (n = 194), prealbumin (n = 13), CRP (n = 9), white blood cell (WBC) (n = 131), and neutrophil-lymphocyte ratio (NLR) (n = 86). Serum albumin level was inversely correlated with all 3 inflammatory biomarkers (CRP, ρ = -0.24, P <0.02; WBC, ρ = -0.15, P <0.001; and NLR, ρ = -0.26, P < 0.001). Change in serum albumin level was inversely correlated with change in NLR (ρ = -0.22, P = 0.044) but not with CRP or WBC. Admission serum albumin level was significantly higher in nourished vs. moderately and/or severely malnourished patients (3.2 [2.7-3.7] vs. 2.7 [2.3-3.0], P = 0.004). Admission serum prealbumin level was significantly higher in nourished vs. moderately and/or severely malnourished patients (9 [7-12] vs. 4 [3-5], P = 0.001). Serum albumin level was inversely correlated with Charlson Comorbidity Index (ρ = 0.20, P = 0.001). Calorie and/or protein delivery in the ICU was not correlated with changes in serum albumin or prealbumin levels. CONCLUSIONS In the ICU, initial serum albumin levels and serial trends are inversely correlated with inflammation. Although initial serum albumin levels are reflective of baseline nutrition status, neither serum albumin level nor serum prealbumin level trends correlate with calorie or protein deficits and should not be used to assess adequacy of nutrition delivery.

Journal ArticleDOI
TL;DR: It is shown that SAP-Mt-HSA NCs can induce dose-dependent cancer cell death with little or no toxicity toward healthy cells and is effective as an anticancer drug delivery agent.

Journal ArticleDOI
TL;DR: A novel "turn-on" fluorescent bioprobe, 1,2,3,4,5-penta(4-carboxyphenyl)pyrrole sodium salt (PPPNa), with aggregation-enhanced emission characteristics was synthesized and exhibited a high selectivity to Al3+ in both simulated serum and fetal calf serum with no interferences from other metal ions or serum components observed.
Abstract: A novel “turn-on” fluorescent bioprobe, 1,2,3,4,5-penta(4-carboxyphenyl)pyrrole sodium salt (PPPNa), with aggregation-enhanced emission characteristics was synthesized for the in situ quantitative detection of Al3+ in serum. It exhibited a high selectivity to Al3+ in both simulated serum and fetal calf serum with no interferences from other metal ions or serum components observed and no isolation required. A weak interaction between PPPNa and serum albumin was found, which caused no interference, but enhanced fluorescence response of PPPNa to Al3+ and improved detection sensitivity. The limit of detection was determined to be 1.50 μmol/L Al3+ in phosphate-buffered saline solution containing 33 μg/mL bovine serum albumin (BSA) and decreased to 0.98 μmol/L as BSA concentration increased to 100 μg/mL. The fluorescence “turn-on” mechanism of the PPPNa probe to detect Al3+ was proposed. A bidentate complex is formed between the carboxy group of PPPNa and Al3+, causing the photoluminescence (PL) emission enhanc...