Adhesion Formation Research Articles

Mechanisms of polyglycolic acid sheet-induced abdominal wall adhesions in hamsters.

A hamster adhesion model was used to investigate the mechanism by which polyglycolic acid (PGA) sheets reinforce the surgical site through the acceleration of postoperative adhesion formation. After receiving electrocautery burns on the inside of the abdominal wall, the hamsters were divided into the PGA group (a PGA sheet was placed on the burned area) and a non-treated group (a PGA sheet was not placed). The degree of adhesion was evaluated at 3, 14, 28, and 56days after burn injury, and the mRNA levels of myeloperoxidase (MPO), tumor necrosis factor (TNF)-α, and transforming growth factor (TGF)-β1 at the surgical sites were measured. Adhesion formation was observed 3days after the burn injury in the non-treated group, but it decreased at 14, 28, and 56days. On the other hand, a significant increase in adhesion formation was observed at 3days in the PGA group relative to the non-treated group, with the increase continuing at 14 and 28days. Significant increases in MPO, TNF-α, and TGF-β1 mRNA levels at the adhesion site were observed 3days after the burn injury in both groups, with the increase continuing in the PGA group, but not in the non-treated group, at 14 and 28days. Acceleration of adhesion formation by PGA may be associated with upregulated MPO, TNF-α, and TGF-β1 mRNA levels.

Abstract 4134384: Sotagliflozin, a Dual Inhibitor of Sodium-Glucose Transporters 1 and 2, Elicits Cardioprotective Effects Through Attenuation of Platelet Activation and Thrombosis

Sodium-glucose cotransporter (SGLT) inhibitors are used in the treatment of type 2 diabetes mellitus (T2DM) and chronic kidney disease (CKD). In the SCORED trial, sotagliflozin (SOTA), a dual SGLT1/2 inhibitor, demonstrated significant reductions in both myocardial infarction (MI) and stroke in patients with T2DM and CKD. These results suggest a cardiovascular (CV) benefit of SOTA in patients with T2DM and CKD who are at increased risk of thromboembolic disease. To investigate the underlying mechanism of CV protection, we evaluated the effects of SOTA on platelet activation and thrombus formation, in both in vivo and ex vivo models, to understand its effects on MI and stroke. Washed human platelets treated with SOTA were stimulated with various agonists and platelet activation was assessed via lumi-aggregometry and flow cytometry. In whole blood, SOTA was evaluated for its potential to reduce platelet adhesion and thrombus formation in the perfusion flow chamber and Total Thrombus formation Analysis System (TTAS) assays. In vivo , mice dosed with SOTA were assessed for thrombus formation at the site of injury in real-time in the cremaster arteriole injury model. To determine the effect of SOTA on hemostasis, we assessed coagulation parameters ex vivo in human whole blood using thromboelastography. Finally, bleeding time was measured in vivo in mice dosed with SOTA using the tail bleeding assay. In washed platelets, SOTA inhibits platelet activation and aggregation in a dose-dependent manner. Similarly, a dose-dependent decrease in platelet adhesion and thrombus formation was observed in whole blood assays. In vivo , platelet accumulation and fibrin formation were decreased in mice dosed with SOTA, however no effect is observed in coagulation parameters or bleeding time. SOTA inhibits platelet activation and thrombus formation with no impact on coagulation parameters or bleeding potential. These findings highlight a potential mechanism through which SOTA reduces the risk of stroke and MI in patients with T2DM and CKD, underscoring the importance of further investigation into the role of SOTA in CV protection, particularly in patients suffering from both T2DM and CKD at high risk of thromboembolic events.

Repositioning of aripiprazole, an anti‑psychotic drug, to sensitize the chemotherapy of pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy with limited therapeutic options. Cisplatin is a primary chemotherapeutic agent utilized in combination with other drugs or radiotherapy for PDAC treatment. However, the severe side effects of cisplatin often necessitate discontinuation of therapy and drug resistance in tumor cells poses significant clinical challenges. Therefore, the development of effective therapeutic strategies is imperative. The present study investigated whether repositioning of the antipsychotic drug aripiprazole could sensitize the anticancer activity of cisplatin in pancreatic cancer at doses calculated by the combination index. The findings indicated that aripiprazole combined with cisplatin to suppress pancreatic cancer cell growth. Notably, the combination notably increased the expression of apoptosis markers, including cleaved caspase‑3, compared with cisplatin alone. Additionally, this combination effectively decreased XIAP and MCL‑1 expression via mitochondrial membrane potential change as revealed by JC‑1 assay, thereby inducing apoptosis. Furthermore, in fluid shear stress assay, the combination of aripiprazole and cisplatin notably inhibited cell adhesion and tumor spheroid formation. Mechanistically, phospho‑kinase array profiles showed that the enhanced anticancer efficacy of the combination treatment could be attributed to the inhibition of STAT3 signaling, which led to a significant reduction in tumor growth in a pancreatic cancer animal model. The results showed that the repositioning of aripiprazole inhibits cancer cell growth by blocking the STAT3 signaling pathway and effectively enhancing cisplatin‑induced apoptosis, thereby suggesting that the combination of aripiprazole and cisplatin may be a potent chemotherapeutic strategy for the treatment of pancreatic cancer.

Abstract 4137045: Sustained Anti-Thrombotic Efficacy of CS585, a Novel Prostacyclin Receptor Agonist, Demonstrates Therapeutic Potential

The formation of occlusive thrombi resulting in myocardial infarction or stroke present a significant challenge for the healthcare community. Activation of the prostacyclin (IP) receptor has been shown to decrease platelet reactivity, however current IP agonists lack a sustained effect in the blood. We have developed CS585, an IP receptor agonist with sustained anti-thrombotic effects in the blood, which could represent a novel prevention strategy in targeting thrombosis. We sought to assess the anti-thrombotic efficacy and pharmacodynamic stability of IP agonists CS585, iloprost and selexipag, in both ex vivo and in vivo models. We evaluated the timeframe of effect of CS585, iloprost, and selexipag in mice following a single IV dose. Inhibition of thrombus formation was measured ex vivo in whole blood under arterial shear rates. In vivo , CS585, iloprost, or selexipag, were administered prior to labeling of platelets and fibrin. Thrombus formation at the site of injury was measured using the cremaster arteriole injury thrombosis assay. CS585 administered to mice prior to blood draw decreases platelet adhesion and blood clot formation under arterial shear conditions. These effects are observed up to 24 hours post-administration; however, the effects of iloprost and selexipag return to pre-treatment levels by 24 hours. In vivo , mice administered iloprost or selexipag demonstrated a decrease in platelet accumulation and fibrin formation, however the effects were abrogated post-administration by 10 minutes and 4 hours, respectively. Administration of CS585, however, demonstrated sustained inhibition of thrombus formation at the site of injury, with inhibitory effects observed at 18 hours post-administration. We have used both in vivo and ex vivo models to demonstrate the anti-thrombotic efficacy of IP receptor agonists. Our results suggest that CS585, a novel IP receptor agonist, sustainably inhibits platelet activation and clot formation for extended periods, in contrast to existing alternatives. This demonstrates a significant improvement in the pharmacodynamic effects of IP receptor agonists in the blood, highlighting CS585 as a novel anti-platelet therapeutic with the potential to treat thrombotic diseases.

Assessment of Biofilm Formation and Anti-Inflammatory Response of a Probiotic Blend in a Cultured Canine Cell Model

Gut dysbiosis and an inflamed bowel are growing concerns in mammals, including dogs. Probiotic supplements have been used to restore the natural microbial community and improve gastrointestinal health. Biofilm formation, antimicrobial activities, and immunological responses of probiotics are crucial to improving gut health. Thus, we tested a commercial probiotic blend (LabMAX-3), a canine kibble additive comprising Lactobacillus acidophilus, Lacticaseibacillus casei, and Enterococcus faecium for their ability to inactivate common enteric pathogens; their ability to form biofilms; epithelial cell adhesion; and their anti-inflammatory response in the Madin-Darby Canine Kidney (MDCK) cell line. Probiotic LabMAX-3 blend or individual isolates showed a strong inhibitory effect against Salmonella enterica, Listeria monocytogenes, enterotoxigenic Escherichia coli, and Campylobacter jejuni. LabMAX-3 formed biofilms comparable to Staphylococcus aureus. LabMAX-3 adhesion to the MDCK cell line (with or without lipopolysaccharide (LPS) pretreatment) showed comparable adhesion and biofilm formation (p < 0.05) to L. casei ATCC 334 used as a control. LabMAX-3 had no cytotoxic effects on the MDCK cell line during 1 h exposure. The interleukin-10 (IL-10) and tumor necrosis factor alpha (TNFα) ratio of LabMAX-3, compared to the L. casei control, showed a significant increase (p < 0.05), indicating a more pronounced anti-inflammatory response. The data show that LabMAX-3, a canine kibble supplement, can improve gastrointestinal health.

Rapid, Controlled Branching Polymerization of Cyanoacrylate via Pathway-Enabled, Site-Specific Branching Initiation.

Controlled branched structures remain a key synthetic limitation for monomeric tissue adhesives because their on-site polymerization that enables adhesion formation requires rapid kinetics, high conversion, and straightforward setup. In this context, site-specific branching initiation by using evolmers is potentially effective for structural control; however, the efficiency and kinetics in current reaction setups persists to be a major challenge. In this paper, an evolmer induces a controlled branching polymerization of cyanoacrylate amid the high monomer reactivity useful in rapid adhesion. The contrasting reactivities between the vinyl and the initiating groups in the evolmer molecule generate a kinetic pathway that favors a control-enabling branching mechanism. Through density functional theory calculations, the reaction pathway toward branching is shown to kinetically favor site-specific initiation by six orders of magnitude than the route toward non-specificity. Reaction monitoring confirms the branching polymerization after the polymerization with the evolmer forms a more compact structure than the linear counterpart. Control of branching density is demonstrated in rapid polymerizations within minutes and in polymerizations completed in an instant. These results provide a template for achieving site-specific branching initiation during adhesion formation and, broadly, where conditions for kinetic control are necessary.

Polyamino Acid Based Zwitterionic Coating can Inhibit Coagulation and Inflammation Through Anti-Fouling and Restoring Microenvironment.

Protein adhesion and thrombosis formation caused by limited surface properties pose great challenges to biomedical implants. Although various hydrophilic coating or drug release coatings are reported, the single coating cannot cope with cases under the condition of complex physiological environment, which causes the coating effect is limited. In this study, a polyamino acid-derived zwitterionic coating is constructed to eliminate reactive oxygen species (ROS) in the microenvironment. It is demonstrated that the coating has excellent hydrophilicity, stability, and lubricity, and can obviously prevent protein adhesion. At the same time, the coating can eliminate hydrogen peroxide and maintain the stability of the microenvironment. The in vivo and in vitro experiments show that the coating has good biocompatibility, and inhibits thrombus. Amino acid zwitterion coating prevents protein deposition, alleviates the inflammatory process, inhibit of thrombosis, reduces the risk of implantable medical devices, and prolongs their service time. Hence, the work paves a new way to develop amino acid based zwitterionic polymer coating that can reduce the implant complications.

A peptide targeting outer membrane protein A of Acinetobacter baumannii exhibits antibacterial activity by reducing bacterial pathogenicity.

The World Health Organization has classified multidrug-resistant (MDR) Acinetobacter baumannii as a significant threat to human health, necessitating the urgent discovery of new antibacterial drugs to combat bacterial resistance. Outer membrane protein A of A. baumannii (AbOmpA) is an outer membrane-anchored β-barrel-shaped pore protein that plays a critical role in bacterial adhesion, invasion, and biofilm formation. Therefore, AbOmpA is considered a key virulence factor of A. baumannii. Herein, we screened three phage display peptide libraries targeting AbOmpA and identified several peptides. Among them, P92 (amino acid sequence: QMGFMTSPKHSV) exhibited the highest binding affinity with AbOmpA, with a KD value of 7.84 nM. In vitro studies demonstrated that although P92 did not directly inhibit bacterial growth, it significantly reduced the invasion and adhesion capabilities of multiple clinical isolates of MDR A. baumannii and concentration-dependently inhibited biofilm formation by acting on OmpA. Furthermore, the polymerase chain reaction results confirmed a significant positive correlation between the antibacterial effect of P92 and OmpA expression levels. Encouragingly, P92 also displayed remarkable therapeutic efficacy against A. baumannii infection in various models, including an in vitro cell infection model, a mouse skin infection model, and a mouse sepsis model. These results highlight P92 as a novel and highly effective antimicrobial molecule specifically targeting the virulence factor AbOmpA.

Intrathecal enalapril reduces adhesion formation in experimentally induced digital flexor tendon sheath injuries in horses.

The objectives of the study were to describe a standing percutaneous adhesion induction model in the digital flexor tendon sheath (DFTS) of horses and to evaluate the effect of intrathecal administration of the angiotensin-converting enzyme (ACE) inhibitor enalapril on tendon healing and adhesion formation. Randomized, blinded, controlled experimental study. Eight healthy horses. A collagenase-induced adhesion model was implemented in the deep digital flexor tendon (DDFT) of both forelimbs under standing ultrasonographic guidance. Daily intrathecal injections of 5 mg enalapril (the treatment condition) were administered to a randomly assigned forelimb for 5 days, with the contralateral limb receiving an equivalent volume of 0.9% NaCl (the control). Lameness and limb circumference were recorded weekly. Horses were euthanized after 8 weeks and evaluated for gross digital flexor tendon sheath (DFTS) adhesions. Tendons were collected for histopathologic scoring of DDFT healing. Paired data were analyzed using a one-sided alternative sign test and longitudinal regression. Multiple DFTS adhesions were formed in control limbs of all horses. The median number of gross DFTS adhesions in treated limbs was less than in control limbs (p = .0039). The average reduction in limb circumference and lameness scores over time occurred faster in treated versus control limbs (p < .025). There were no differences in DDFT histopathologic scores between groups. The standing percutaneous DFTS adhesion induction model demonstrated that intrathecal enalapril reduced DFTS adhesion formation, lameness scores, and limb circumference over time. Intrathecal enalapril administration may reduce morbidity in horses with naturally occurring tendon injuries.

Enhanced Biodegradation of Silk Fibroin Hydrogel for Preventing Postoperative Adhesion.

An absorbable adhesion barrier is a medical device that prevents postoperative adhesion and matches its biodegradation time with the regeneration period of its target tissues, which is important for antiadhesion effects. Physical hydrogels of Bombyx mori silk fibroin (SF) proteins are degradable in vivo. However, their biodegradation time is too long to exert antiadhesion effects. To shorten the biodegradation time of the SF hydrogels, we decreased the molecular weight (MW) of the SF proteins by alkaline treatment and prepared low-MW (LMW) SF hydrogels. The hydrogels contained less β-sheet crystalline and more amorphous structures than conventional, high-MW (HMW) SF hydrogels. Because of the potential loosened SF molecular structures in the hydrogel networks, the LMW SF hydrogels showed enhanced biodegradation (i.e., shorter in vitro enzymatic biodegradation time and faster in vivo biodegradation rate) as well as a lower affinity for plasma proteins and fibroblasts, which are involved in postoperative adhesion formation. An antiadhesion test using a rat abdominal adhesion model demonstrated that the LMW SF hydrogel applied to the abraded cecum was almost completely degraded within two weeks postimplantation, with a significantly lower adhesion severity score than that in the untreated model rat group. Conversely, the HMW SF hydrogel remained between the cecum and abdominal wall, with the same adhesion severity as that of the untreated model rat group. Therefore, we concluded that the antiadhesion effects of SF hydrogels were induced by enhanced biodegradation. The results of this study indicate the potential of LMW SF hydrogels as absorbable adhesion barriers.

Carbohydrate Research Mini-review Relationships between bacteria and the mucus layer

The mucus layer on epithelial cells is an essential barrier, as well as a nutrient-rich niche for bacteria, forming a dynamic, functional and symbiotic ecosystem and first line of defense against invading pathogens. Particularly bacteria in biofilms are very difficult to eradicate. The extensively O-glycosylated mucins are the main glycoproteins in mucus that interact with microbes. For example, mucins act as adhesion receptors and nutritional substrates for gut bacteria. Mucins also play important roles in immune responses, and they control the composition of the microbiome, primarily due to the abundance of complex O-glycans. In inflammation or infection, the structures of mucin O-glycans can change and thus affect mucin function, impact biofilm formation and the induction of virulence pathways in bacteria. In turn, bacteria can support host cell growth, mucin production and can stimulate changes in the host immune system and responses leading to healthy tissue function. The external polysaccharides of bacteria are critical for controlling adhesion and biofilm formation. It is therefore important to understand the relationships between the mucus layer and microbes, the mechanisms and regulation of the biosynthesis of mucins, of bacterial surface polysaccharides, and adhesins. This knowledge can provide biomarkers, vaccines and help to develop new approaches for improved therapies, including antibiotic treatments.

Severe Flexor Digitorum Profundus Muscular Adhesion by Pseudo-Volkmann's Contracture without Fracture: A Case Report and Literature Review

AbstractVolkmann's ischemic contracture is a condition characterized by permanent ischemic damage to muscles and nerves due to vascular insufficiency, resulting in flexion contractures of the affected limb. In contrast, pseudo-Volkmann's contracture presents with similar clinical features but lacks ischemic damage and has the potential for complete recovery. We report a case of a 39-year-old man who developed failure of extension in the middle and ring fingers of the left hand following blunt forearm trauma from a rolling machine. Despite no skin breakage or fracture, his symptoms progressively worsened over 2 months without treatment. Surgical exploration 2 years later revealed severe adhesions of the flexor digitorum profundus muscle at the myotendinous junction to the ulnar periosteum, with immediate recovery after release. This case highlights pseudo-Volkmann's contracture in an adult without fracture, likely due to blunt trauma causing delayed adhesion formation.

Effects of a Monophasic Cross-Linked Hyaluronic-Acid Gel in Prevention against Postoperative Adhesion Formation in Rats

Effects of a Monophasic Cross-Linked Hyaluronic-Acid Gel in Prevention against Postoperative Adhesion Formation in Rats

Rosmarinic Acid Exhibits Antifungal and Antibiofilm Activities Against Candida albicans: Insights into Gene Expression and Morphological Changes

Candida species, opportunistic pathogens that cause various infections, pose a significant threat due to their ability to form biofilms that resist antifungal treatments and immune responses. The increasing resistance of Candida spp. and the limited availability of effective treatments have prompted the research of natural compounds as alternative therapies. This study assessed the antifungal properties of RA against Candida species, focusing on its impact on C. albicans biofilms and the underlying mechanisms. The antifungal efficacy of RA was evaluated using the CLSI M27-A3 microdilution method on both fluconazole-susceptible and -resistant strains. Biofilm formation by C. albicans was assessed through a crystal violet assay, while its antibiofilm activity was analyzed using an MTT assay and field emission scanning electron microscopy (FESEM). Gene expression related to biofilm formation was studied using quantitative real-time PCR (qRT-PCR), and statistical analysis was performed with an ANOVA. Among the 28 Candida strains tested, RA exhibited minimum inhibitory concentration (MIC) values ranging from 160 to 1280 μg/mL. At a 640 μg/mL concentration, it significantly reduced the expression of genes associated with adhesion (ALS3, HWP1, and ECE1), hyphal development (UME6 and HGC1), and hyphal cAMP-dependent protein kinase regulators (CYR1, RAS1, and EFG1) in RAS1-cAMP-EFG1 pathway (p &lt; 0.05). FESEM analysis revealed a reduction in hyphal networks and disruptions on the cell surface. Our study is the first to demonstrate the effects of RA on C. albicans adhesion, hyphae development, and biofilm formation through gene expression analysis with findings supported by FESEM. This approach distinguishes our study from previous studies on the effect of RA on Candida. However, the high MIC values of RA limit its antifungal potential. Therefore, more extensive research using innovative methods is required to increase the antifungal effect of RA.

Enhancing Antibacterial Properties of Titanium Implants through Covalent Conjugation of Self-Assembling Fmoc-Phe-Phe Dipeptide on Titania Nanotubes.

Bacterial infections and biofilm formation are significant challenges for medical implants. While titanium nanotube engineering improves biocompatibility, it cannot prevent bacterial adhesion and biofilm formation. Optimizing the biomaterial's surface chemistry is vital for its desired functioning in the biological environment. This study demonstrates the covalent conjugating of the self-assembling dipeptide N-fluorenylmethyloxycarbonyl-diphenylalanine (Fmoc-FF) onto titanium nanotube surfaces (TiNTs) without altering the topography. Fmoc-FF peptides, in conjugation with TiNTs, can inhibit biofilm formation, eradicate pre-existing biofilms, and kill bacteria. This functionalization imparts antibacterial properties to the surface while retaining beneficial nanotube topography, synergistically enhancing bioactivity. Surface characterization by XPS, FT-IR, EDS, and SEM confirmed the successful functionalization. Bacterial adhesion experiments showed a significantly improved antibacterial activity of the functionalized TiNT surfaces. This study opens future possibilities for associating biomedical applications such as cell-cell interactions, tissue engineering, and controlled drug delivery of multifunctional self-assembling short peptides with implant materials through surface functionalization.

The multiple roles of macrophages in peritoneal adhesion

AbstractPeritoneal adhesion (PA) refers to the abnormal adhesion of the peritoneum either with the peritoneum itself or with tissues and organs that is caused by abdominopelvic surgery, abdominal infection or peritoneal inflammation. PA is associated with various clinical complications, such as abdominal pain and distension, intestinal obstruction, gastrointestinal disorders and female infertility, and adversely affects the quality of life of patients. Macrophages are essential for PA formation and can undergo polarization into classically activated macrophages (M1) and alternatively activated macrophages (M2), which are influenced by the peritoneal microenvironment. By releasing proinflammatory cytokines and reactive oxygen species, M1 macrophages promote peritoneal inflammatory reactions and the resultant formation of adhesion. In contrast, M2 macrophages secrete anti‐inflammatory cytokines and growth factors to inhibit PA formation and to promote repair and healing of peritoneal tissues, and thereby play a significant anti‐inflammatory role. This review comprehensively explores the function and mechanism of macrophages and their subtypes in PA formation to gain insight into the prevention and treatment of PA based on the modulation of macrophages.

High-resolution snapshots of the talin auto-inhibitory states suggest roles in cell adhesion and signaling

Talin regulates crucial cellular functions, including cell adhesion and motility, and affects human diseases. Triggered by mechanical forces, talin plays crucial roles in facilitating the formation of focal adhesions and recruiting essential focal adhesion regulatory elements such as vinculin. The structural flexibility allows talin to fine-tune its signaling responses. This study presents our 2.7 Å cryoEM structures of talin, which surprisingly uncovers several auto-inhibitory states. Contrary to previous suggestions, our structures reveal that (1) the first and last three domains are not involved in maintaining talin in its closed state and are mobile, (2) the talin F-actin and membrane binding domain are loosely attached and thus available for binding, and (3) the main force-sensing domain is oriented with its vinculin binding sites ready for release. These structural snapshots offer insights and advancements in understanding the dynamic talin activation mechanism, which is crucial for mediating cell adhesion.

CS585, a novel prostacyclin receptor agonist, demonstrates sustained efficacy in vivo in the prevention of thrombosis

Abstract Background Uncontrolled platelet activity resulting from cardiovascular disease can lead to occlusive thrombi, culminating in myocardial infarction or stroke. Despite major advances in anti-platelet therapeutics, many patients remain at risk. Although prostacyclin (IP) receptor agonists are currently used for the treatment of pulmonary arterial hypertension (PAH), activation of the IP receptor has been shown to decrease platelet reactivity. However, engaging the IP receptor as a therapeutic target was previously considered unviable due to the lack of a sustained effect of current IP agonists in the blood. The development of an IP agonist with sustained effects in the blood would represent a novel prevention strategy in targeting platelet hyperreactivity and thrombosis. Purpose Assess the stability profile of CS585, an IV and orally bioavailable IP agonist, compared to FDA-approved IP agonists iloprost and selexipag, with regards to sustained activity in vivo in the blood in limiting platelet activation and thrombosis. Methods Using ex vivo and in vivo mouse models, we assessed the timeframe of effect of CS585, iloprost and selexipag in blood. Blood was drawn from wild-type mice 24 hours following a single IV dose of CS585, iloprost or selexipag. Platelet adhesion and blood clotting were measured using perfusion flow chamber at arterial shear and total thrombus activation system (T-TAS), respectively. In vivo, platelets and fibrin were labelled 24 hours post IV or oral administration of CS585, iloprost or selexipag, and accumulation at the site of injury was measured using the cremaster arteriole injury thrombosis assay. Results Blood drawn from mice administered CS585 was observed to show a decrease in platelet adhesion and clot formation in the perfusion flow chamber and T-TAS assays. The effects of iloprost and selexipag are no longer observed at 24 hours post-administration. Administration of CS585 resulted in sustained inhibition of platelet accumulation and fibrin formation in the laser-induced cremaster arteriole thrombosis assay up to 18 hours post-administration. In mice administered iloprost, a decrease in thrombus formation was observed 10 minutes post-administration, but thrombus size returned to vehicle levels by 4 hours. Selexipag-dosed mice demonstrated inhibition of thrombus formation up to 4 hours, but effects were no longer observed at 18 hours. Conclusions CS585, a novel IP agonist, inhibits platelet activation and clot formation up to 24 hours post-administration. In both in vivo and ex vivo models, we demonstrate the sustained effects of CS585. In contrast, current FDA-approved IP agonists do not possess an effect profile sufficient to target the IP receptor in blood. By overcoming the sustainability challenge facing IP agonists, CS585 represents a novel approach to anti-platelet treatment of thrombotic diseases, which could include thrombosis, VTE, secondary prevention after MI and stroke, and PAH.

GJA4 gene inhibition may represent a potential target for novel antithrombotic therapies

Abstract The GJA4 gene encodes a protein called connexin 37, a component of gap junctions in vascular endothelial cells, crucial in regulating endothelial function and influencing inflammation, platelet adhesion and thrombus formation. This gene deletion in mice diminished thrombus formation in vitro in human blood. In these circumstances, connexin inhibition with pharmacological agents may represent potential avenues for developing novel antithrombotic agents. Aim To investigate whether the GJA4 rs618675 T&amp;gt;C variant is a risk factor for progressing atherosclerosis and cardiovascular (CV) events in an asymptomatic free of apparent CAD from a Portuguese population. Methods A prospective study was performed with 1421 individuals without apparent CV disease (73.6% male, aged 52.2±8.3 years) followed during an extended period of 7.2±5.1 years). GJA4 rs618675 T&amp;gt;C variant was genotyped by TaqMan real-time PCR technique (Applied Biosystems). Conventional, anthropometric, biochemical and clinical risk factors were studied. Bivariate analysis and multivariate Cox regression adjusted for age, gender, traditional risk factors, biochemical markers, and the genotypes under study was performed to determine which variables were, significantly and independently, associated with CV events. Kaplan-Meier's estimate assessed the prognosis. Results Bivariate analysis showed that 50.6% of wild genotype (TT) carriers had CV events vs. 66.2% without events. Of the risk genotype (CC) carriers, 10.1% had CV events, and 3.4% did not. After the Kaplan-Meier analysis, the TT carriers had 90% CV event-free survival time and the CC risk carriers had only 64% of event-free survival. Finally, after adjustment, CC genotype remained in the equation with an HR of 3.1 (p=0.003) and CT heterozygous with HR of 1.6 (p=0.043), together with Hypertension (HR 3.0; p&amp;lt;0.0001), Smoking habits (HR 2.3; p=0.001) and Diabetes (HR 1.9; p=0.015). Conclusion: The CC risk genotype of the GJA4 rs618675 represented an independent risk factor for progressing atherosclerosis and CV events in a Portuguese Population. Thrombus formation often begins with the adhesion of platelets to the endothelium, and connexin 37 may influence this process. The inhibition of connexin 37 emerges as a promising candidate for future cardiovascular prevention as well as for the development of new antithrombotic drugs.

Polyphenol-treatment without preceding glutaraldehyde fixation: a potential paradigm change for bioprosthetic heart valves

Abstract Background Glutaraldehyde (GA) is the common fixative agent for bioprosthetic heart valves (BHVs). However, its chemical instability can expose calcium binding sites and, at commercially used concentrations, GA does not ensure effective immunological tolerance, triggering an immune response correlated to degeneration. Recently, polyphenols (PPs) achieved an almost complete xenoantigens inactivation in GA-fixed BHVs ensuring chemical stability of the treated tissue while improving mechanical characteristics and adding anti-infective and anti-thrombotic properties [1-4]. Purpose A new PP-based treatment has been introduced as a potential GA substitute in BHV manufacturing. The unique chemical properties of PPs permit them to interact with the tissue through stable chemical bonds without depolymerization over time, achieving several improvements that promise to extend the long-term durability of BHVs (Fig.1). Methods The study compared the effects of two cross-linking methods on bovine pericardial tissue: (1) traditional fixation in GA, and (2) treatment with PPs without GA. The type of chemical interaction between PPs and tissue was evaluated through nuclear magnetic resonance. The xenoantigens inactivation was quantified in-vitro by ELISA test and in-vivo in a humanized mouse animal model. Biomechanical properties were assessed through uniaxial stress-strain tests and cross-link density through the shrinkage temperature test. The protective effect against bacterial adhesion was evaluated against a strain of S aureus, while the inhibition of thrombosis was evaluated in-vivo in a pig animal model and in-vitro in a blood-loop using bovine blood with radio-labeled platelets. Results PPs effectuated multiple chemical bonds with and within the pericardium including cross-links based on covalent and hydrogen bonds, stacking, and electrostatic interactions. The inactivation of over 90% of surface-xenoantigens of the treated tissue allowed for superior biocompatibility (compared to &amp;lt;50% by commercial GA concentrations). The increase in elongation exhibited by PP-treated tissue confirmed excellent biomechanical features (Fig.2) while a sufficient degree of cross-linking was demonstrated through an adequate shrinkage temperature. Furthermore, a significant degree of bacterial adhesion (86% inhibition evaluated with S. aureus) and thrombus formation (Fig.2, up to 90% inhibition) were observed. Conclusion There is a real clinical need for improved chemical stability, calcification resistance, and immunological tolerance of current BHVs (surgical and transcatheter). PP technology may substitute the use of GA extending their performance and durability, thereby opening trans-catheter heart valves to younger patients. Reducing the need for mechanical heart valves would also address the associated risks of lifelong anticoagulation therapy.Figure 1Figure 2