ABSTRACT
AIMS: To investigate the effect of tumor necrosis factor (TNF) on the growth of human periodontal ligament (PDL) cells, their osteogenic differentiation and modulation of their matrix secretion in vitro. METHODS: The influence of 10â¯ng/ml TNF on proliferation and metabolic activity of PDL cells was analyzed by cell counting (DAPI [4',6-diamidino-2-phenylindole] staining) and the MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay. In addition, cells were cultured under control conditions and osteogenic conditions (media containing 10â¯mM ß-glycerophosphate). Quantitative expression analysis of genes encoding the osteogenic markers alkaline phosphatase (ALP), collagen type I alpha 1 chain (COL1A1), osteoprotegerin (OPG), and osteopontin (OPN) was performed after 7 and 14 days of cultivation. Calcium deposits were stained with alizarin red. RESULTS: Our studies showed that 10â¯ng/ml TNF did not affect the survival and metabolic activity of PDL cells. Quantitative expression analysis revealed that long-term cultures with TNF impaired osteogenic cell fate at early and late developmental stages. Furthermore, TNF significantly reduced matrix secretion in PDL cells. CONCLUSION: The present data confirm TNF as a regulatory factor of proinflammatory remodeling that influences the differentiation behavior but not the metabolism and cell proliferation of the periodontium. Therefore, TNF represents an interesting target for the regulation of orthodontic remodeling processes in the periodontium.
ABSTRACT
Biohybrid tissue-engineered vascular grafts (TEVGs) promise long-term durability due to their ability to adapt to hosts' needs. However, the latter calls for sensitive non-invasive imaging approaches to longitudinally monitor their functionality, integrity, and positioning. Here, we present an imaging approach comprising the labeling of non-degradable and degradable TEVGs' components for their in vitro and in vivo monitoring by hybrid 1H/19F MRI. TEVGs (inner diameter 1.5 mm) consisted of biodegradable poly(lactic-co-glycolic acid) (PLGA) fibers passively incorporating superparamagnetic iron oxide nanoparticles (SPIONs), non-degradable polyvinylidene fluoride scaffolds labeled with highly fluorinated thermoplastic polyurethane (19F-TPU) fibers, a smooth muscle cells containing fibrin blend, and endothelial cells. 1H/19F MRI of TEVGs in bioreactors, and after subcutaneous and infrarenal implantation in rats, revealed that PLGA degradation could be faithfully monitored by the decreasing SPIONs signal. The 19F signal of 19F-TPU remained constant over weeks. PLGA degradation was compensated by cells' collagen and α-smooth-muscle-actin deposition. Interestingly, only TEVGs implanted on the abdominal aorta contained elastin. XTT and histology proved that our imaging markers did not influence extracellular matrix deposition and host immune reaction. This concept of non-invasive longitudinal assessment of cardiovascular implants using 1H/19F MRI might be applicable to various biohybrid tissue-engineered implants, facilitating their clinical translation.
Subject(s)
Blood Vessel Prosthesis , Magnetic Resonance Imaging , Polylactic Acid-Polyglycolic Acid Copolymer , Tissue Engineering , Tissue Scaffolds , Animals , Tissue Scaffolds/chemistry , Tissue Engineering/methods , Magnetic Resonance Imaging/methods , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Rats , Humans , Male , Polyglycolic Acid/chemistry , Lactic Acid/chemistry , Polyurethanes/chemistry , Myocytes, Smooth Muscle/cytology , Biocompatible Materials/chemistry , Rats, Sprague-Dawley , Magnetic Iron Oxide Nanoparticles/chemistryABSTRACT
Active targeting can enhance precision and efficacy of drug delivery systems (DDS) against cancers. Riboflavin (RF) is a promising ligand for active targeting due to its biocompatibility and high riboflavin-receptor expression in cancers. In this study, RF-targeted 4-arm polyethylene glycol (PEG) stars conjugated with Paclitaxel (PTX), named PEG PTX RF, were evaluated as a targeted DDS. In vitro, PEG PTX RF exhibited higher toxicity against tumor cells compared to the non-targeted counterpart (PEG PTX), while free PTX displayed the highest acute toxicity. In vivo, all treatments were similarly effective, but PEG PTX RF-treated tumors showed fewer proliferating cells, pointing to sustained therapy effects. Moreover, PTX-treated animals' body and liver weights were significantly reduced, whereas both remained stable in PEG PTX and PEG PTX RF-treated animals. Overall, our targeted and non-targeted DDS reduced PTX's adverse effects, with RF targeting promoted drug uptake in cancer cells for sustained therapeutic effect.
Subject(s)
Drug Delivery Systems , Paclitaxel , Polyethylene Glycols , Riboflavin , Paclitaxel/pharmacology , Paclitaxel/chemistry , Riboflavin/pharmacology , Riboflavin/chemistry , Animals , Humans , Mice , Polyethylene Glycols/chemistry , Cell Line, Tumor , Mice, Inbred BALB C , Polymers/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Antineoplastic Agents, Phytogenic/chemistry , Mice, Nude , Neoplasms/drug therapy , Neoplasms/pathology , Xenograft Model Antitumor Assays , FemaleABSTRACT
Millions of people worldwide currently suffer from chronic kidney disease (CKD), requiring kidney replacement therapy at the end stage. Endeavors to better understand CKD pathophysiology from an omics perspective have revealed major molecular players in several sample sources. Focusing on non-invasive sources, gut microbial communities appear to be disturbed in CKD, while numerous human urinary peptides are also dysregulated. Nevertheless, studies often focus on isolated omics techniques, thus potentially missing the complementary pathophysiological information that multidisciplinary approaches could provide. To this end, human urinary peptidome was analyzed and integrated with clinical and fecal microbiome (16S sequencing) data collected from 110 Non-CKD or CKD individuals (Early, Moderate, or Advanced CKD stage) that were not undergoing dialysis. Participants were visualized in a three-dimensional space using different combinations of clinical and molecular data. The most impactful clinical variables to discriminate patient groups in the reduced dataspace were, among others, serum urea, haemoglobin, total blood protein, urinary albumin, urinary erythrocytes, blood pressure, cholesterol measures, body mass index, Bristol stool score, and smoking; relevant variables were also microbial taxa, including Roseburia, Butyricicoccus, Flavonifractor, Burkholderiales, Holdemania, Synergistaceae, Enterorhabdus, and Senegalimassilia; urinary peptidome fragments were predominantly derived from proteins of collagen origin; among the non-collagen parental proteins were FXYD2, MGP, FGA, APOA1, and CD99. The urinary peptidome appeared to capture substantial variation in the CKD context. Integrating clinical and molecular data contributed to an improved cohort separation compared to clinical data alone, indicating, once again, the added value of this combined information in clinical practice.
ABSTRACT
Patients with chronic kidney disease (CKD) are at an increased cardiovascular risk compared with the general population, which is driven, at least in part, by mechanisms that are uniquely associated with kidney disease. In CKD, increased levels of oxidative stress and uraemic retention solutes, including urea and advanced glycation end products, enhance non-enzymatic post-translational modification events, such as protein oxidation, glycation, carbamylation and guanidinylation. Alterations in enzymatic post-translational modifications such as glycosylation, ubiquitination, acetylation and methylation are also detected in CKD. Post-translational modifications can alter the structure and function of proteins and lipoprotein particles, thereby affecting cellular processes. In CKD, evidence suggests that post-translationally modified proteins can contribute to inflammation, oxidative stress and fibrosis, and induce vascular damage or prothrombotic effects, which might contribute to CKD progression and/or increase cardiovascular risk in patients with CKD. Consequently, post-translational protein modifications prevalent in CKD might be useful as diagnostic biomarkers and indicators of disease activity that could be used to guide and evaluate therapeutic interventions, in addition to providing potential novel therapeutic targets.
Subject(s)
Cardiovascular Diseases , Protein Processing, Post-Translational , Renal Insufficiency, Chronic , Humans , Cardiovascular Diseases/metabolism , Cardiovascular Diseases/etiology , Renal Insufficiency, Chronic/metabolism , Renal Insufficiency, Chronic/complications , Heart Disease Risk Factors , Oxidative Stress , Biomarkers/metabolism , GlycosylationABSTRACT
Chronic kidney disease (CKD) significantly increases cardiovascular risk and mortality, and the accumulation of uremic toxins in the circulation upon kidney failure contributes to this increased risk. We thus performed a screening for potential novel mediators of reduced cardiovascular health starting from dialysate obtained after hemodialysis of patients with CKD. The dialysate was gradually fractionated to increased purity using orthogonal chromatography steps, with each fraction screened for a potential negative impact on the metabolic activity of cardiomyocytes using a high-throughput MTT-assay, until ultimately a highly purified fraction with strong effects on cardiomyocyte health was retained. Mass spectrometry and nuclear magnetic resonance identified the metabolite mycophenolic acid-ß-glucuronide (MPA-G) as a responsible substance. MPA-G is the main metabolite from the immunosuppressive agent MPA that is supplied in the form of mycophenolate mofetil (MMF) to patients in preparation for and after transplantation or for treatment of autoimmune and non-transplant kidney diseases. The adverse effect of MPA-G on cardiomyocytes was confirmed in vitro, reducing the overall metabolic activity and cellular respiration while increasing mitochondrial reactive oxygen species production in cardiomyocytes at concentrations detected in MMF-treated patients with failing kidney function. This study draws attention to the potential adverse effects of long-term high MMF dosing, specifically in patients with severely reduced kidney function already displaying a highly increased cardiovascular risk.
ABSTRACT
The crosstalk of the heart with distant organs such as the lung, liver, gut, and kidney has been intensively approached lately. The kidney is involved in (1) the production of systemic relevant products, such as renin, as part of the most essential vasoregulatory system of the human body, and (2) in the clearance of metabolites with systemic and organ effects. Metabolic residue accumulation during kidney dysfunction is known to determine cardiovascular pathologies such as endothelial activation/dysfunction, atherosclerosis, cardiomyocyte apoptosis, cardiac fibrosis, and vascular and valvular calcification, leading to hypertension, arrhythmias, myocardial infarction, and cardiomyopathies. However, this review offers an overview of the uremic metabolites and details their signaling pathways involved in cardiorenal syndrome and the development of heart failure. A holistic view of the metabolites, but more importantly, an exhaustive crosstalk of their known signaling pathways, is important for depicting new therapeutic strategies in the cardiovascular field.
Subject(s)
Cardio-Renal Syndrome , Vascular Diseases , Humans , Heart , Kidney/metabolism , Signal Transduction , Lung/metabolismABSTRACT
BACKGROUND AND HYPOTHESIS: The risk of Diabetic Kidney Disease (DKD) progression is significant despite renin-angiotensin system (RAS) blocking agents treatment. Current clinical tools cannot predict whether or not patients will respond to the treatment with RAS-inhibitors (RASi). We aimed to investigate if proteome analysis could identify urinary peptides as biomarkers that could predict the response to angiotensin-converting enzyme inhibitor (ACEi) and angiotensin receptor blockers (ARBs) treatment to avoid DKD progression. Furthermore, we investigated the comparability of the estimated glomerular filtration rate (eGFR), calculated using four different GFR-equations, for DKD progression. METHODS: We evaluated urine samples from a discovery cohort of 199 diabetic patients treated with RASi. DKD progression was defined based on eGFR percentage slope results between visits (â¼1 year) and for the entire period (â¼3 year) based on the eGFR values of each GFR-equation. Urine samples were analysed using capillary electrophoresis coupled mass spectrometry. Statistical analysis was performed between the uncontrolled (patients who did not respond to RASi treatment) and controlled kidney function groups (patients who responded to the RASi treatment). Peptides were combined in a support vector machine-based model. The area under the receiver operating characteristic curve (AUC) was used to evaluate the risk prediction models in two independent validation cohorts treated with RASi. RESULTS: The classification of patients into uncontrolled and controlled kidney function varies depending on the GFR-equation used, despite the same sample set. We identified 227 peptides showing nominal significant difference and consistent fold changes between uncontrolled and controlled patients in at least three methods of eGFR calculation. These included fragments of collagens, alpha-1-antitrypsin, antithrombin-III, CD99 antigen, and uromodulin. A model based on 189 of 227 peptides (DKDp189) showed a significant prediction of non-response to the treatment/DKD progression in two independent cohorts. CONCLUSIONS: The DKDp189 model demonstrates potential as a predictive tool for guiding treatment with RASi in diabetic patients.
ABSTRACT
Background: In the 'Die Deutsche Diabetes Dialyse Studie' (4D Study), treatment of patients with type 2 diabetes mellitus (T2DM) on haemodialysis (HD) with atorvastatin compared with placebo had no significant effect on the first composite primary major adverse cardiovascular event (MACE) endpoint of death from cardiac causes, fatal stroke, non-fatal myocardial infarction or non-fatal stroke. In this study we analysed first and recurrent events in 1255 patients from the 4D Study. Methods: We conducted an event history analysis to investigate the effects of previous clinical events on the risk of different endpoints in the total patient group and after stratification by randomization group. Results: During a median follow-up of 4 years, a total of 548 MACEs occurred, with 469 first and 79 recurrent events. The most frequent event was sudden cardiac death, followed by death due to infection/sepsis. Of the 548 total MACEs, 260 occurred in the atorvastatin group and 288 in the placebo group [hazard ratio 0.91 (95% confidence interval 0.76-1.07), P = .266]. Interestingly, analyses of the baseline hazard functions for first and recurrent events as a function of time after randomization demonstrated that the risks of the composite primary endpoint continually increased in the placebo group with increasing time in the study, whereas the risk in the atorvastatin group remained constant after ≈1.5 years. Conclusion: This recurrent and total event analysis from the 4D Study underscores the high risk of sudden cardiac death and death due to infection/sepsis in patients with T2DM receiving HD and raises the hypothesis that atorvastatin may stabilize cardiovascular risk only after 1-2 years in this high-risk population.
ABSTRACT
(1) Background: Kidney and cardiovascular diseases are responsible for a large fraction of population morbidity and mortality. Early, targeted, personalized intervention represents the ideal approach to cope with this challenge. Proteomic/peptidomic changes are largely responsible for the onset and progression of these diseases and should hold information about the optimal means of treatment and prevention. (2) Methods: We investigated the prediction of renal or cardiovascular events using previously defined urinary peptidomic classifiers CKD273, HF2, and CAD160 in a cohort of 5585 subjects, in a retrospective study. (3) Results: We have demonstrated a highly significant prediction of events, with an HR of 2.59, 1.71, and 4.12 for HF, CAD, and CKD, respectively. We applied in silico treatment, implementing on each patient's urinary profile changes to the classifiers corresponding to exactly defined peptide abundance changes, following commonly used interventions (MRA, SGLT2i, DPP4i, ARB, GLP1RA, olive oil, and exercise), as defined in previous studies. Applying the proteomic classifiers after the in silico treatment indicated the individual benefits of specific interventions on a personalized level. (4) Conclusions: The in silico evaluation may provide information on the future impact of specific drugs and interventions on endpoints, opening the door to a precision-based medicine approach. An investigation into the extent of the benefit of this approach in a prospective clinical trial is warranted.
ABSTRACT
Chronic kidney disease (CKD) patients undergoing dialysis are at high risk of bone fractures. CKD-induced mineral and bone disorder is extended to periodontal disease due to changes in the ionic composition of saliva in CKD patients, dysregulating mineralization, hindering regeneration and thereby promoting the progression of dental complications. Despite the importance of cementum for overall oral health, the mechanisms that regulate its development and regeneration are not well comprehended, and a lack of sufficient in vitro experimental models has hindered research progress. In this study, the impact of experimental conditions on the calcification of cementoblasts was systematically investigated, aimed at establishing a standardized and validated model for the calcification of cementoblasts. The effects of phosphate, calcium, ascorbic acid, ß-glycerolphosphate, dexamethasone, and fetal calf serum on the calcification process of cementoblasts were analyzed over a wide range of concentrations and time points by investigating calcium content, cell viability, gene expression and kinase activity. Cementoblasts calcified in a concentration- and time-dependent manner with higher concentrations of supplements cause a higher degree of calcification but decreased cell viability. Phosphate and calcium have a significantly stronger effect on cementoblast calcification processes compared to osteogenic supplements: ascorbic acid, ß-glycerolphosphate, and dexamethasone induce calcification over a wide range of osteogenic signalling pathways, with osteopontin being a central target of gene regulation. Conversely, treatment with ascorbic acid, ß-glycerolphosphate, and dexamethasone leads to activating only selected pathways, especially promoting bone sialoprotein expression. The developed and validated cementoblast calcification protocol, incubating up to 60% confluent cementoblasts with 1.9 mmol L-1 of phosphate supplementation for a reasonable, multi-pathway calcification induction and 10 mmol L-1 ß-glycerolphosphate, 75 µmol L-1 ascorbic acid and 10 nmol L-1 dexamethasone for a reasonable osteogenic differentiation-based calcification induction, provides standard in vitro experimental models for better understanding cementoblast function and regeneration.
Subject(s)
Calcinosis , Dental Cementum , Humans , Calcium , Glycerophosphates , Osteogenesis , Renal Dialysis , Periodontium , Calcium, Dietary , Ascorbic Acid/pharmacology , Dexamethasone/pharmacologyABSTRACT
One of the major components in cementum extracellular matrix is bone sialoprotein (BSP). BSP knockout (Ibsp) mice were reported to have a nonfunctional hypo-mineralized cementum, as well as detachment and disorganization of the periodontal ligament tissue. However, studies investigating the influence of Ibsp in cementoblasts are missing yet. This study investigates the influences of Bsp in three cementoblasts cell lines (OCCM.30-WT,IbspΔNterm, and IbspKAE). The mRNA expression of cementoblast and osteoclast markers (Col1a1, Alpl, Ocn, Runx2, Ctsk, Rankl and Opg) and the cell morphology were compared. Additionally, a functional monocyte adhesion assay was performed. To understand the influence of external stimuli, the effect of Ibsp was investigated under static compressive force, mimicking the compression side of orthodontic tooth movement. Cementoblasts with genotype IbspΔNterm and IbspKAE showed slight differences in cell morphology compared to OCCM.30-WT, as well as different gene expression. Under compressive force, the Ibsp cell lines presented expression pattern markers similar to the OCCM.30-WT cell line. However, Cathepsin K was strongly upregulated in IbspΔNterm cementoblasts under compressive force. This study provides insight into the role of BSP in cementoblasts and explores the influence of BSP on periodontal ligament tissues. BSP markers in cementoblasts seem to be involved in the regulation of cementum organization as an important factor for a functional periodontium. In summary, our findings provide a basis for investigations regarding molecular biology interactions of BSP in cementoblasts, and a supporting input for understanding the periodontal and cellular cementum remodeling.
Subject(s)
Dental Cementum , Mice , Animals , Integrin-Binding Sialoprotein/genetics , Integrin-Binding Sialoprotein/metabolism , Dental Cementum/metabolism , Mice, Knockout , Cell Line , Gene ExpressionSubject(s)
Cardiovascular Diseases , Heart Diseases , Renal Insufficiency, Chronic , Humans , Renal Insufficiency, Chronic/complications , Renal Insufficiency, Chronic/diagnosis , Renal Insufficiency, Chronic/epidemiology , Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/epidemiology , Comorbidity , Risk FactorsABSTRACT
The identification of mediators for physiologic processes, correlation of molecular processes, or even pathophysiological processes within a single organ such as the kidney or heart has been extensively studied to answer specific research questions using organ-centered approaches in the past 50 years. However, it has become evident that these approaches do not adequately complement each other and display a distorted single-disease progression, lacking holistic multilevel/multidimensional correlations. Holistic approaches have become increasingly significant in understanding and uncovering high dimensional interactions and molecular overlaps between different organ systems in the pathophysiology of multimorbid and systemic diseases like cardiorenal syndrome because of pathological heart-kidney crosstalk. Holistic approaches to unraveling multimorbid diseases are based on the integration, merging, and correlation of extensive, heterogeneous, and multidimensional data from different data sources, both -omics and nonomics databases. These approaches aimed at generating viable and translatable disease models using mathematical, statistical, and computational tools, thereby creating first computational ecosystems. As part of these computational ecosystems, systems medicine solutions focus on the analysis of -omics data in single-organ diseases. However, the data-scientific requirements to address the complexity of multimodality and multimorbidity reach far beyond what is currently available and require multiphased and cross-sectional approaches. These approaches break down complexity into small and comprehensible challenges. Such holistic computational ecosystems encompass data, methods, processes, and interdisciplinary knowledge to manage the complexity of multiorgan crosstalk. Therefore, this review summarizes the current knowledge of kidney-heart crosstalk, along with methods and opportunities that arise from the novel application of computational ecosystems providing a holistic analysis on the example of kidney-heart crosstalk.
Subject(s)
Cardio-Renal Syndrome , Ecosystem , Humans , Cross-Sectional Studies , Kidney , HeartABSTRACT
Fos-like antigen 1 (Fosl1) is a protein that belongs to the Fos family of transcription factors. Fosl1 has an impact on (i) carcinogenesis, (ii) acute kidney injury, and (iii) fibroblast growth factor expression. Recently, the nephroprotective effect of Fosl1 by the preservation of Klotho expression was recently identified. The identification of a link between Fosl1 and Klotho expression provides an entirely new field of nephroprotection.
ABSTRACT
Chronic kidney disease (CKD) affects a huge portion of the world's population and frequently leads to cardiovascular diseases (CVDs). It might be because of common risk factors between chronic kidney disease and cardiovascular diseases. Renal dysfunction caused by chronic kidney disease creates oxidative stress which in turn leads to cardiovascular diseases. Oxidative stress causes endothelial dysfunction and inflammation in heart which results in atherosclerosis. It ends in clogging of veins and arteries that causes cardiac stroke and myocardial infarction. To develop an innovative therapeutic approach and new drugs to treat these diseases, it is important to understand the pathophysiological mechanism behind the CKD and CVDs and their interrelationship. Natural phytoconstituents of plants such as polyphenolic compounds are well known for their medicinal value. Polyphenols are plant secondary metabolites with immense antioxidant properties, which can protect from free radical damage. Nowadays, polyphenols are generating a lot of buzz in the scientific community because of their potential health benefits especially in the case of heart and kidney diseases. This review provides a detailed account of the pathophysiological link between CKD and CVDs and the pharmacological potential of polyphenols and their nanoformulations in promoting cardiovascular and renal health.
Subject(s)
Cardiovascular Diseases , Glomerulonephritis , Renal Insufficiency, Chronic , Humans , Cardiovascular Diseases/drug therapy , Cardiovascular Diseases/etiology , Chronic Disease , Kidney , Risk Factors , Renal Insufficiency, Chronic/drug therapy , Renal Insufficiency, Chronic/complicationsABSTRACT
BACKGROUND & AIMS: Growing evidence supports a role of gut-derived metabolites in nonalcoholic fatty liver disease (NAFLD), but the relation of endotoxin levels with gut permeability and NAFLD stage remains unclear. This systematic review with meta-analysis aims to provide further insights. METHODS: PubMed, Embase, and Cochrane Library were searched for studies published until January 2022 assessing blood endotoxins in patients with NAFLD. Meta-analyses and univariate/multivariate meta-regression, as well as correlation analyses, were performed for endotoxin values and potential relationships to disease stage, age, sex, parameters of systemic inflammation, and metabolic syndrome, as well as liver function and histology. RESULTS: Forty-three studies were included, of which 34 were used for meta-analyses. Blood endotoxin levels were higher in patients with simple steatosis vs liver-healthy controls (standardized mean difference, 0.86; 95% confidence interval, 0.62-1.11) as well as in patients with nonalcoholic steatohepatitis vs patients with nonalcoholic fatty liver/non-nonalcoholic steatohepatitis (standardized mean difference, 0.81; 95% confidence interval, 0.27-1.35; P = .0078). Consistently, higher endotoxin levels were observed in patients with more advanced histopathological gradings of liver steatosis and fibrosis. An increase of blood endotoxin levels was partially attributed to a body mass index rise in patients with NAFLD compared with controls. Nevertheless, significant increases of blood endotoxin levels in NAFLD retained after compensation for differences in body mass index, metabolic condition, or liver enzymes. Increases in blood endotoxin levels were associated with increases in C-reactive protein concentrations, and in most cases, paralleled a rise in markers for intestinal permeability. CONCLUSION: Our results support blood endotoxin levels as relevant diagnostic biomarker for NAFLD, both for disease detection as well as staging during disease progression, and might serve as surrogate marker of enhanced intestinal permeability in NAFLD. Registration number in Prospero: CRD42022311166.
Subject(s)
Non-alcoholic Fatty Liver Disease , Humans , Non-alcoholic Fatty Liver Disease/pathology , Endotoxins/metabolism , Liver/pathology , Inflammation/pathology , Biomarkers/metabolismABSTRACT
Hemodialysis fails to remove protein-bound uremic toxins that are attributed with high cardiovascular risk. Application of adsorption materials is a viable strategy, but suitable biocompatible adsorbents are still not available. Here, we demonstrate that adsorbents based on the bottom-up assembly of the intrinsically biocompatible protein cage ferritin are applicable for toxin adsorption. Due to the size-exclusion effect of its pores, only small molecules such as uremic toxins can enter the protein cage. Protein redesign techniques that target selectively the inner surface were used to introduce anchor sites for chemical modification. Porous crystalline adsorbents were fabricated by bottom-up assembly of the protein cage. Linkage of up to 96 phenylic or aliphatic molecules per container was verified by ESI-MS. Materials based on unmodified ferritin cages can already adsorb the uremic toxins. The adsorption capacity could be increased by about 50% through functionalization with hydrophobic molecules reaching 458 µg g-1 for indoxyl sulfate. The biohybrid materials show no contamination with endotoxins and do not activate blood platelets. These findings demonstrate the great potential of protein-based adsorbents for the clearance of uremic toxins: modifications enhance toxin adsorption without diminishing the biocompatibility of the final protein-based material.