Efficient Hydroxyapatite Extraction from Salmon Bone Waste: An Improved Lab-Scaled Physico-Chemico-Biological Process.

The demand for novel tissue grafting and regenerative wound care biomaterials is growing as traditional options often fall short in biocompatibility, functional integration with human tissue, associated cost(s), and sustainability. Salmon aquaculture generates significant volumes of waste, offering a sustainable opportunity for biomaterial production, particularly in osteo-conduction/-induction, and de novo clinical/surgical bone regeneration. Henceforth, this study explores re-purposing salmon waste through a standardized pre-treatment process that minimizes the biological waste content, followed by a treatment stage to remove proteins, lipids, and other compounds, resulting in a mineral-rich substrate. Herein, we examined various methods-alkaline hydrolysis, calcination, and NaOH hydrolysis-to better identify and determine the most efficient and effective process for producing bio-functional nano-sized hydroxyapatite. Through comprehensive chemical, physical, and biological assessments, including Raman spectroscopy and X-ray diffraction, we also optimized the extraction process. Our modified and innovative alkaline hydrolysis-calcination method yielded salmon-derived hydroxyapatite with a highly crystalline structure, an optimal Ca/P ratio, and excellent biocompatibility. The attractive nano-scale cellular/tissular properties and favorable molecular characteristics, particularly well-suited for bone repair, are comparable to or even surpass those of synthetic, human, bovine, and porcine hydroxyapatite, positioning it as a promising candidate for use in tissue engineering, wound healing, and regenerative medicine indications.

Unravelling the Antifibrinolytic Mechanism of Action of the 1,2,3-Triazole Derivatives.

A new family of antifibrinolytic drugs has been recently discovered, combining a triazole moiety, an oxadiazolone, and a terminal amine. Two of the molecules of this family have shown activity that is greater than or similar to that of tranexamic acid (TXA), the current antifibrinolytic gold standard, which has been associated with several side effects and whose use is limited in patients with renal impairment. The aim of this work was to thoroughly examine the mechanism of action of the two ideal candidates of the 1,2,3-triazole family and compare them with TXA, to identify an antifibrinolytic alternative active at lower dosages. Specifically, the antifibrinolytic activity of the two compounds (1 and 5) and TXA was assessed in fibrinolytic isolated systems and in whole blood. Results revealed that despite having an activity pathway comparable to that of TXA, both compounds showed greater activity in blood. These differences could be attributed to a more stable ligand-target binding to the pocket of plasminogen for compounds 1 and 5, as suggested by molecular dynamic simulations. This work presents further evidence of the antifibrinolytic activity of the two best candidates of the 1,2,3-triazole family and paves the way for incorporating these molecules as new antifibrinolytic therapies.

In Vivo Efficacy of an Adhesive Bioresorbable Patch to Treat Aortic Dissections.

Endovascular repair of aortic dissection still presents significant limitations. Preserving the mechanical and biological properties set by the aortic microstructure is critical to the success of implantable grafts. In this paper, we present the performance of an adhesive bioresorbable patch designed to cover the entry tear of aortic dissections. We demonstrate the power of using a biomimetic scaffold in a vascular environment.

A Tunable Soft Silicone Bioadhesive for Secure Anchoring of Diverse Medical Devices to Wet Biological Tissue.

Silicone is utilized widely in medical devices for its compatibility with tissues and bodily fluids, making it a versatile material for implants and wearables. To effectively bond silicone devices to biological tissues, a reliable adhesive is required to create a long-lasting interface. BioAdheSil, a silicone-based bioadhesive designed to provide robust adhesion on both sides of the interface is introduced here, facilitating bonding between dissimilar substrates, namely silicone devices and tissues. The adhesive's design focuses on two key aspects: wet tissue adhesion capability and tissue-infiltration-based long-term integration. BioAdheSil is formulated by mixing soft silicone oligomers with siloxane coupling agents and absorbents for bonding the hydrophobic silicone device to hydrophilic tissues. Incorporation of biodegradable absorbents eliminates surface water and controls porosity, while silane crosslinkers provide interfacial strength. Over time, BioAdheSil transitions from nonpermeable to permeable through enzyme degradation, creating a porous structure that facilitates cell migration and tissue integration, potentially enabling long-lasting adhesion. Experimental results demonstrate that BioAdheSil outperforms commercial adhesives and elicits no adverse response in rats. BioAdheSil offers practical utility for adhering silicone devices to wet tissues, including long-term implants and transcutaneous devices. Here, its functionality is demonstrated through applications such as tracheal stents and left ventricular assist device lines.

Single-Cell RNA Sequencing Reveals That Adaptation of Human Aortic Endothelial Cells to Antiproliferative Therapies Is Modulated by Flow-Induced Shear Stress.

BACKGROUND: Endothelial cells (ECs) are capable of quickly responding in a coordinated manner to a wide array of stresses to maintain vascular homeostasis. Loss of EC cellular adaptation may be a potential marker for cardiovascular disease and a predictor of poor response to endovascular pharmacological interventions such as drug-eluting stents. Here, we report single-cell transcriptional profiling of ECs exposed to multiple stimulus classes to evaluate EC adaptation. METHODS: Human aortic ECs were costimulated with both pathophysiological flows mimicking shear stress levels found in the human aorta (laminar and turbulent, ranging from 2.5 to 30 dynes/cm2) and clinically relevant antiproliferative drugs, namely paclitaxel and rapamycin. EC state in response to these stimuli was defined using single-cell RNA sequencing. RESULTS: We identified differentially expressed genes and inferred the TF (transcription factor) landscape modulated by flow shear stress using single-cell RNA sequencing. These flow-sensitive markers differentiated previously identified spatially distinct subpopulations of ECs in the murine aorta. Moreover, distinct transcriptional modules defined flow- and drug-responsive EC adaptation singly and in combination. Flow shear stress was the dominant driver of EC state, altering their response to pharmacological therapies. CONCLUSIONS: We showed that flow shear stress modulates the cellular capacity of ECs to respond to paclitaxel and rapamycin administration, suggesting that while responding to different flow patterns, ECs experience an impairment in their transcriptional adaptation to other stimuli.

Optimization of 3D autologous chondrocyte-seeded polyglycolic acid scaffolds to mimic human ear cartilage.

Auricular reconstruction in children with microtia is one of the more complex procedures in plastic surgery. Obtaining sufficient native material to build an ear requires harvesting large fragments of rib cartilage in children. Herein, we investigated how to optimize autologous chondrocyte isolation, expansion and re-implantation using polyglycolic acid (PGA) scaffolds for generating enough cartilage to recapitulate a whole ear starting from a small ear biopsy. Ear chondrocytes isolated from human microtia subjects grew slower than microtia rib or healthy ear chondrocytes and displayed a phenotypic shift due to the passage number. Rabbit ear chondrocytes co-cultured with mesenchymal stem cells (MSC) at a 50 : 50 ratio recapitulated the cartilage biological properties in vitro. However, PGA scaffolds with different proportions of rabbit chondrocytes and MSC did not grow substantially in two months when subcutaneously implanted in immunosuppressed mice. In contrast, rabbit chondrocyte-seeded PGA scaffolds implanted in immunocompetent rabbits formed a cartilage 10 times larger than the original PGA scaffold. This cartilage mimicked the biofunctional and mechanical properties of an ear cartilage. These results indicate that autologous chondrocyte-seeded PGA scaffolds fabricated following our optimized procedure have immense potential as a solution for obtaining enough cartilage for auricular reconstruction and opens new avenues to redefine autologous cartilage replacement.

A data-driven approach to manage type 2 diabetes mellitus through digital health: The Klivo Intervention Program protocol (KIPDM).

BACKGROUND: Digital therapeutics, an emerging type of medical approach, is defined as evidence-based therapeutic interventions through qualified software programs that help prevent, manage, or treat chronic diseases such as type 2 diabetes mellitus (T2DM), which has high social and economic burden. Klivo, a startup certified by the Brazilian Society of Diabetes, developed the first digital therapeutic product for managing T2DM in Brazil, reaching 21 of 24 states. Klivo has continuously been improving its model of behavior change on the basis of an intensive lifestyle intervention method that addresses individuals' needs-the Klivo Intervention Program for T2DM (KIPDM). To test the most recent version of the KIPDM, we will evaluate the ongoing management of daily life habits in patients with T2DM by measuring clinically significant outcomes. To improve the transparency of further results, here we will present the study protocol and detail the plan for the research project, including the study design and the analysis strategies. METHODS: The KIPDM will be sponsored by health plans and healthcare provider organizations and will be free for patients (adults aged ≥ 18 years and <65 years; and glycated hemoglobin ≥ 7%). The program will be based on a 6-month management process that will supervise patients remotely. The program will include educational classes via the Klivo app, text messages, or e-mails. Evaluation will include objectively assessing clinical, laboratory, and behavioral outcomes such as health-related quality of life, mental health, medication adherence, and healthcare utilization. For this, validated electronic questionnaires will be available through the Klivo app. The primary outcome will be glycated hemoglobin (HbA1c) values. The secondary outcome will be time in target blood glucose range (TIR) estimated by capillary glycemia. Other outcomes of interest will be evaluated at baseline and stipulated time points (3 and 6 months after the start of the program). EXPECTED OUTCOMES: KIPDM patients should present improved HbA1c and TIR along the intervention as compared to baseline values. Findings from this study will provide insights into the health improvement of T2DM and other cardiometabolic conditions such as hypertension, dyslipidemia, and obesity by using a digital therapeutic strategy. By analyzing the patient's health over time, this study will also contribute to understanding comorbidities associated with this chronic condition in the Brazilian population.

1,2,3-Triazole Derivatives as Novel Antifibrinolytic Drugs.

Fibrinolysis is a natural process that ensures blood fluidity through the removal of fibrin deposits. However, excessive fibrinolytic activity can lead to complications in different circumstances, such as general surgery or severe trauma. The current antifibrinolytic drugs in the market, aminocaproic acid (EACA) and tranexamic acid (TXA), require high doses repetitively to maintain their therapeutic effect. These high doses are related to a number of side effects such as headaches, nasal symptoms, or gastrointestinal discomfort and severely limit their use in patients with renal impairment. Therefore, the discovery of novel antifibrinolytics with a higher specificity and lower dosage could vastly improve the applicability of these drugs. Herein, we synthesized a total of ten compounds consisting of a combination of three key moieties: an oxadiazolone, a triazole, and a terminal amine. The IC50 of each compound was calculated in our clot lysis assays, and the best candidate (1) provided approximately a 2.5-fold improvement over the current gold standard, TXA. Molecular docking and molecular dynamics were used to perform a structure-activity relationship (SAR) analysis with the lysine binding site in the Kringle 1 domain of plasminogen. This analysis revealed that 1,2,3-triazole was crucial for the activity, enhancing the binding affinity through pi-pi stacking and polar interactions with Tyr72. The results presented in this work open the door to further investigate this new family as potential antifibrinolytic drugs.

Comparing different metabolic indexes to predict type 2 diabetes mellitus in a five years follow-up cohort: The Baependi Heart Study.

This study evaluates the association of anthropometric indexes and the incidence of type 2 diabetes mellitus (T2DM) after a 5-year follow-up. This analysis included 1091 middle-aged participants (57% women, mean age 47 ± 15 years) who were free of T2DM at baseline and attended two health examinations cycles [cycle 1 (2005-2006) and cycle 2 (2010-2013)]. As expected, the participants who developed T2DM after five years (3.8%) had the worst metabolic profile with higher hypertension, dyslipidemia, and obesity rates. Besides, using mixed-effects logistic regression and adjustment for sex, age, and glucose, we found that one unit increase in body adiposity index (BAI) was associated with an 8% increase in their risk of developing T2DM (odds ratio [OR] = 1.08 [95% CI, 1.02-1.14]) and visceral adiposity index (VAI) was associated with a risk increase of 11% (OR = 1.11 [95% CI, 1.00-1.22]). Moreover, a one-unit increase in the triglycerides-glucose index (TyG) was associated with more than four times the risk of developing T2DM (OR = 4.27 [95% CI, 1.01-17.97]). The interquartile range odds ratio for the continuous predictors showed that TyG had the best discriminating performance. However, when any of them were additionally adjusted for waist circumference (WC) or even body mass index (BMI), all adiposity indexes lost the effect in predicting T2DM. In conclusion, TyG had the most substantial predictive power among all three indexes. However, neither BAI, VAI, nor TyG were superior to WC or BMI for predicting the risk of developing T2DM in a middle-aged normoglycemic sample in this rural Brazilian population.

A Dynamic, In Vitro BBB Model to Study the Effects of Varying Levels of Shear Stress.

The blood-brain barrier (BBB) consists of a tight network of blood capillaries in the brain that separate the circulatory system from the central nervous system. Its particular properties are based on the dynamic interaction between cerebral endothelial cells and other surrounding cells, especially astrocytes. We have designed and synthesized a three-dimensional scaffold that recapitulates the main hallmarks of the BBB extracellular matrix and serves as a platform to co-culture human brain microvascular endothelial cells and human cortical astrocytes. The scaffold can be exposed to flow, thereby allowing the study of flow-mediated pathways at the BBB.

The disruptive innovation and the pre-texts methodology / A inovação disruptiva e a metodologia pré-textos

Abstract: Introduction: The experience report describes the protocol used in one of the activities carried out during the initiative aimed at the search for health impact solutions through disruptive innovation - "IDEA2 Global, Guidance and transforming connections for innovators in medical technology", in May 2019, at the Institute of Medical Engineering and Science, Massachusetts Institute of Technology (IMES MIT). Experience report: The Pre-Texts methodology was chosen to stimulate creativity and instill the curiosity inherent in the search for solutions to complex problems, through the reading of a challenging text and related activities in a workshop format. Bringing together professionals from various segments and nationalities, the two-hour and forty-five-minute period was the time spent on the workshop inspired by practices from some Latin American countries. Discussion: Through observation, it was observed that participants were engaged and fascinated by hands-on activities, amid the active reading of a text on neural connections in creative processes. The feedback from the evaluation on the workshop confirmed the facilitators' impression. Conclusion: The Pre-Texts methodology is a strategy that can be applied in heterogeneous groups and can include skills such as creativity and collaboration. Thus, the use of this methodology should be encouraged in other similar situations.

Resumo: Introdução: O relato de experiência descreve o protocolo utilizado em uma das atividades realizadas durante a iniciativa destinada à busca por soluções de impacto em saúde através da inovação disruptiva - "IDEA2 Global, Orientação e conexões transformadoras para inovadores em tecnologia médica", em maio de 2019, no Instituto de Engenharia Médica e Ciência, Massachusetts Institute of Technology (IMES MIT). Relato de Experiência: A metodologia Pré-Textos foi escolhida para estimular a criatividade e instigar a curiosidade inerentes à busca por soluções de problemas complexos, através da leitura de um texto desafiador e atividades relacionadas, em formato de workshop. Reunindo profissionais de vários segmentos e nacionalidades, o período de duas horas e quarenta e cinco minutos foi o tempo dispensado ao workshop inspirado em práticas oriundas de alguns países da América Latina. Discussão: Por meio da observação participante, constatou-se que os partícipes se mostraram entusiasmos e engajados por atividades "mão na massa", em meio a leitura ativa de um texto sobre conexões neurais em processos criativos. A devolutiva da avaliação sobre o workshop confirmou a impressão dos facilitadores. Conclusão: A metodologia Pré-Textos é uma estratégia passível de aplicação em grupos heterogêneos, podendo contemplar habilidades como a criatividade e a colaboração. Assim, estimula-se a utilização desta metodologia em outras situações semelhantes.

Triglyceride glucose index as a tool to motivate early lifestyle modification in young adults at diabetes risk: The Baependi Heart Study.

Considering that the incidence of type 2 diabetes mellitus (T2DM) has been increasing especially in developing countries and becoming a global public health problem, this study aims to evaluate the association between triglyceride glucose index (TyG) - which is a mathematical product of the fasting blood glucose and triglyceride levels - and incident T2DM in an adult sample in the Baependi Heart Study (BHS). The data were from the BHS cohort consisting of two periods: cycle 1 (2005-2006; n = 1712; 119 families) and cycle 2 (2010-2013; n = 3017; 127 families). A total of 1121 individuals (both sexes, 18-100 years) were selected if they were assessed in both cycles and not diagnosed with T2DM at baseline (cycle 1). Our findings showed that a participant's risk of developing T2DM increased almost 10 times for a one-unit increase in the TyG (odds ratio OR = 10.17, 95% CI, 7.51-13.93). The association when stratified by age was OR = 28.13 [95% CI, 14.03-56.41] for young adults, meaning that the risk of developing T2DM increased more than 28 times for a one-unit increase in the TyG. For the other groups, young middle-aged adults, old middle-aged adults, and seniors, we found OR = 4.84 [95% CI, 2.91-8.06], OR = 28.73 [95% CI, 10.63-77.65, and OR = 9.88 [95% CI, 3.16-30.90], respectively. A higher TyG implies a significant increase in the risk of developing T2DM, which could be an important screening tool to target early lifestyle intervention in Brazil.

Relationship between marital status and incidence of type 2 diabetes mellitus in a Brazilian rural population: The Baependi Heart Study.

Many factors influence the incidence of type 2 diabetes mellitus (T2DM). Here, we investigated the associations between socio-demographic characteristics and familial history with the 5-year incidence of T2DM in a family-based study conducted in Brazil. T2DM was defined as baseline fasting blood glucose ≥ 126 mg/dL or the use of any hypoglycaemic drug. We excluded individuals with T2DM at baseline or if they did not attend two examination cycles. After exclusions, we evaluated a sample of 1,125 participants, part of the Baependi Heart Study (BHS). Mixed-effects logistic regression models were used to assess T2DM incident given different characteristics. At the 5-year follow-up, the incidence of T2DM was 6.7% (7.2% men and 6.3% women). After adjusting for age, sex, and education status, the model that combined marital and occupation status, skin color, and familial history of T2DM provided the best prediction for T2DM incidence. Only marital status was independently associated with T2DM incidence. Individuals that remained married, despite having significantly increased their weight, were significantly less likely to develop diabetes than their divorced counterparts.

Shear stress modulates inner blood retinal barrier phenotype.

The vascular endothelium responds to the shear stress generated by blood flow and changes function to maintain tissue homeostasis and adapt to injury in pathological conditions. Shear stress in the retinal circulation is altered in patients with retinal vascular diseases, such as diabetic retinopathy. Therefore, we aimed to study the effect of laminar shear stress on barrier properties and on the release of proinflammatory cytokines in human retinal microvascular endothelial cells (HRMEC). HRMEC were cultured in Ibidi flow chambers and exposed to laminar shear stress (0-50 dyn/cm2) for 24-48 h. Tight junction distribution (ZO-1 and claudin-5) and cytokine production were determined by immunofluorescence and ELISA, respectively. The chemotactic effect of conditioned media exposed to shear stress was determined by measuring lymphocyte transmigration in Transwells. We found that cells exposed to moderately low shear stress (1.5 and 5 dyn/cm2) showed enhanced distribution of membrane ZO-1 and claudin-5 and decreased production of the proinflammatory cytokines IL-8, CCL2, and IL-6 compared to static conditions and high shear stress values. Moreover, conditioned media from cells exposed to low shear stress, had the lowest chemotactic effect to recruit lymphocytes compared to conditioned media from cells exposed to static and high shear stress conditions. In conclusion, high shear stress and static flow, associated to impaired retinal circulation, may compromise the inner blood retinal barrier phenotype and barrier function in HRMEC.

Assessment of the Angiogenic Potential of 2-Deoxy-D-Ribose Using a Novel in vitro 3D Dynamic Model in Comparison With Established in vitro Assays.

Angiogenesis is a highly ordered physiological process regulated by the interaction of endothelial cells with an extensive variety of growth factors, extracellular matrix components and mechanical stimuli. One of the most important challenges in tissue engineering is the rapid neovascularization of constructs to ensure their survival after transplantation. To achieve this, the use of pro-angiogenic agents is a widely accepted approach. The study of angiogenesis has gained momentum over the last two decades. Although there are various in vitro, ex vivo, and in vivo angiogenesis models that enable testing of newly discovered pro-angiogenic agents, the problem with researching angiogenesis is the choice of the most appropriate assay. In vivo assays are the most representative and reliable models, but they are expensive, time-consuming and can cause ethical concerns whereas in vitro assays are relatively inexpensive, practical, and reproducible, but they are usually lack of enabling the study of more than one aspect of angiogenesis, and they do not fully represent the complexity of physiological angiogenesis. Therefore, there is a need for the development of an angiogenesis model that allows the study of angiogenesis under physiologically more relevant, dynamic conditions without causing ethical concerns. Accordingly, in this study, we developed 3D in vitro dynamic angiogenesis model, and we tested the angiogenic potential of 2-deoxy-D-ribose (2dDR) in comparison with vascular endothelial growth factor (VEGF) using newly developed in vitro 3D dynamic model and well-established in vitro models. Our results obtained using conventional in vitro assays demonstrated that 2dDR promoted proliferation, migration and tube formation of human aortic endothelial cells (HAECs) in a dose-dependent manner. Then, the angiogenic activity of 2dDR was further assessed using the newly developed 3D in vitro model, which enabled the monitoring of cell proliferation and infiltration simultaneously under dynamic conditions. Our results showed that the administration of 2dDR and VEGF significantly enhanced the outgrowth of HAECs and the cellular density under either static or dynamic conditions.

Subendothelial matrix components influence endothelial cell apoptosis in vitro.

The programmed form of cell death (apoptosis) is essential for normal development of multicellular organisms. Dysregulation of apoptosis has been linked with embryonal death and is involved in the pathophysiology of various diseases. Specifically, endothelial apoptosis plays pivotal roles in atherosclerosis whereas prevention of endothelial apoptosis is a prerequisite for neovascularization in tumors and metastasis. Endothelial biology is intertwined with the composition of subendothelial basement membrane proteins. Apoptosis was induced by addition of tumor necrosis factor-α to cycloheximide-sensitized endothelial cells. Cells were either grown on polystyrene culture plates or on plates precoated with healthy basement membrane proteins (collagen IV, fibronectin, or laminin) or collagen I. Our results reveal that proteins of healthy basement membrane alleviate cytokine-induced apoptosis whereas precoating with collagen type I had no significant effect on apoptosis by addition of tumor necrosis factor-α to cycloheximide-sensitized endothelial cells compared with cells cultured on uncoated plates. Yet, treatment with transforming growth factor-ß1 significantly reduced the rate of apoptosis endothelial cells grown on collagen I. Detailed analysis reveals differences in intracellular signaling pathways for each of the basement membrane proteins studied. We provide additional insights into the importance of basement membrane proteins and the respective cytokine milieu on endothelial biology. Exploring outside-in signaling by basement membrane proteins may constitute an interesting target to restore vascular function and prevent complications in the atherosclerotic cascade.

Cerebral Small Vessel Disease: A Review Focusing on Pathophysiology, Biomarkers, and Machine Learning Strategies.

Cerebral small vessel disease (cSVD) has a crucial role in lacunar stroke and brain hemorrhages and is a leading cause of cognitive decline and functional loss in elderly patients. Based on underlying pathophysiology, cSVD can be subdivided into amyloidal and non-amyloidal subtypes. Genetic factors of cSVD play a pivotal role in terms of unraveling molecular mechanism. An important pathophysiological mechanism of cSVD is blood-brain barrier leakage and endothelium dysfunction which gives a clue in identification of the disease through circulating biological markers. Detection of cSVD is routinely carried out by key neuroimaging markers including white matter hyperintensities, lacunes, small subcortical infarcts, perivascular spaces, cerebral microbleeds, and brain atrophy. Application of neural networking, machine learning and deep learning in image processing have increased significantly for correct severity of cSVD. A linkage between cSVD and other neurological disorder, such as Alzheimer's and Parkinson's disease and non-cerebral disease, has also been investigated recently. This review draws a broad picture of cSVD, aiming to inculcate new insights into its pathogenesis and biomarkers. It also focuses on the role of deep machine strategies and other dimensions of cSVD by linking it with several cerebral and non-cerebral diseases as well as recent advances in the field to achieve sensitive detection, effective prevention and disease management.

Chondroitin Sulphate Attenuates Atherosclerosis in ApoE Knockout Mice Involving Cellular Regulation of the Inflammatory Response.

Chondroitin sulphate (CS) has long been used to treat osteoarthritis. Some investigations have also shown that the treatment with CS could reduce coronary events in patients with heart disease but no studies have identified the mechanistic role of these therapeutic effects. We aimed to investigate how the treatment with CS can interfere with the progress of atherosclerosis. The aortic arch, thoracic aorta and serum were obtained from apolipoprotein E (ApoE) knockout mice fed for 10 weeks with high-fat diet and then treated with CS (300 mg/kg, n = 15) or vehicle (n = 15) for 4 weeks. Atheromatous plaques were highlighted in aortas with Oil Red staining and analysed by microscopy. ApoE knockout mice treated with CS exhibited attenuated atheroma lesion size by 68% as compared with animals receiving vehicle. Serum lipids, glucose and C-reactive protein were not affected by treatment with CS. To investigate whether CS locally affects the inflamed endothelium or the formation of foam cells in plaques, human endothelial cells and monocytes were stimulated with tumour necrosis factor α or phorbol myristate acetate in the presence or absence of CS. CS reduced the expression of vascular cell adhesion molecule 1, intercellular adhesion molecule 1 and ephrin-B2 and improved the migration of inflamed endothelial cells. CS inhibited foam cell formation in vivo and concomitantly CD36 and CD146 expression and oxidized low-density lipoprotein uptake and accumulation in cultured activated human monocytes and macrophages. Reported cardioprotective effects of CS may arise from modulation of pro-inflammatory activation of endothelium and monocytes and foam cell formation.

Optimizing Glutaraldehyde-Fixed Tissue Heart Valves with Chondroitin Sulfate Hydrogel for Endothelialization and Shielding against Deterioration.

Porcine glutaraldehyde-fixed pericardium is widely used to replace human heart valves. Despite the stabilizing effects of glutaraldehyde fixation, the lack of endothelialization and the occurrence of immune reactions contribute to calcification and structural valve deterioration, which is particularly significant in young patients, in whom valve longevity is crucial. This report shows an optimization system with which to enhance endothelialization of fixed pericardium to mimic the biological function of a native heart valve. The glutaraldehyde detoxification, together with the application of a biodegradable methacrylated chondroitin sulfate hydrogel, reduces aldehydes cytotoxicity, increases the migration and proliferation of endothelial cells and the recruitment of endothelial cell progenitors, and confers thromboresistance in fixed pericardium. The combination of glutaraldehyde detoxification and a coating with chondroitin sulfate hydrogel promotes in situ mechanisms of endothelialization in fixed pericardium. We offer a new solution for improving the long life of bioprosthetic valves and exploring the means of making valves suitable to endothelialization.

Targeting STUB1-tissue factor axis normalizes hyperthrombotic uremic phenotype without increasing bleeding risk.

Chronic kidney disease (CKD/uremia) remains vexing because it increases the risk of atherothrombosis and is also associated with bleeding complications on standard antithrombotic/antiplatelet therapies. Although the associations of indolic uremic solutes and vascular wall proteins [such as tissue factor (TF) and aryl hydrocarbon receptor (AHR)] are being defined, the specific mechanisms that drive the thrombotic and bleeding risks are not fully understood. We now present an indolic solute-specific animal model, which focuses on solute-protein interactions and shows that indolic solutes mediate the hyperthrombotic phenotype across all CKD stages in an AHR- and TF-dependent manner. We further demonstrate that AHR regulates TF through STIP1 homology and U-box-containing protein 1 (STUB1). As a ubiquitin ligase, STUB1 dynamically interacts with and degrades TF through ubiquitination in the uremic milieu. TF regulation by STUB1 is supported in humans by an inverse relationship of STUB1 and TF expression and reduced STUB1-TF interaction in uremic vessels. Genetic or pharmacological manipulation of STUB1 in vascular smooth muscle cells inhibited thrombosis in flow loops. STUB1 perturbations reverted the uremic hyperthrombotic phenotype without prolonging the bleeding time, in contrast to heparin, the standard-of-care antithrombotic in CKD patients. Our work refines the thrombosis axis (STUB1 is a mediator of indolic solute-AHR-TF axis) and expands the understanding of the interconnected relationships driving the fragile thrombotic state in CKD. It also establishes a means of minimizing the uremic hyperthrombotic phenotype without altering the hemostatic balance, a long-sought-after combination in CKD patients.