Neutrophils as drivers of vascular injury in sickle cell disease.

While neutrophils are the main effectors of protective innate immune responses, they are also key players in inflammatory pathologies. Sickle cell disease (SCD) is a genetic blood disorder in which red blood cells (RBCs) are constantly destroyed in the circulation which generates a highly inflammatory environment that culminates in vascular occlusions. Vaso-occlusion is the hallmark of SCD and a predictor of disease severity. Neutrophils initiate and propagate SCD-related vaso-occlusion through adhesive interactions with the activated and dysfunctional endothelium, sickle RBCs, and platelets, leading to acute and chronic complications that progress to irreversible organ damage and ultimately death. The use of SCD humanized mouse models, in combination with in vivo imaging techniques, has emerged as a fundamental tool to understand the dynamics of neutrophils under complex inflammatory contexts and their contribution to vascular injury in SCD. In this review, we discuss the various mechanisms by which circulating neutrophils sense and respond to the wide range of stimuli present in the blood of SCD patients and mice. We argue that the central role of neutrophils in SCD can be rationalized to develop targets for the management of clinical complications in SCD patients.

DNase aggravates intestinal microvascular injury in IBD patients by releasing NET-related proteins.

Neutrophils accumulate in the inflammatory mucosa of patients with inflammatory bowel disease (IBD), and excessive release of NETs (neutrophil extracellular traps may be one of the important factors that cause IBD progression. However, the specific mechanism underlying vascular injury caused by NETs remains unclear. Immunofluorescence, ELISA, and flow cytometry were used in this study to detect the expression of NETs and DNase in the tissue and peripheral blood samples of patients with IBD. DSS mouse model was used to detect colon injury and vascular permeability. We found that NETs and DNase levels increased in the colon of patients with IBD. We found an increase in the activity of NET-related MPO released by DNase. DNase released NET-related proteins and damaged vascular endothelial cells in vitro. In DSS mouse model, the synchronous increase of DNase and NETs in the colon leads to an increase in vascular injury markers (CD44, sTM). DNase aggravated colon injury and increased vascular permeability in vivo, which was inhibited by gentamicin sulfate (GS). GS does not reduce the expression of DNase, but rather reduces the release of NET-related proteins to protect vascular endothelium by inhibiting DNase activity. MPO and histones synergistically damaged the vascular endothelium, and vascular injury can be improved by their active inhibitors. We further found that H2 O2 is an important substrate for MPO induced vascular damage. In conclusion, in IBD, DNase, and NET levels increased synchronously in the lesion area and released NET-related proteins to damage the vascular endothelium. Therefore, targeting DNase may be beneficial for the treatment of IBD.

Perivascular CLICK-gelatin delivery of thrombospondin-2 small interfering RNA decreases development of intimal hyperplasia after arterial injury.

Bypass graft failure occurs in 20%-50% of coronary and lower extremity bypasses within the first-year due to intimal hyperplasia (IH). TSP-2 is a key regulatory protein that has been implicated in the development of IH following vessel injury. In this study, we developed a biodegradable CLICK-chemistry gelatin-based hydrogel to achieve sustained perivascular delivery of TSP-2 siRNA to rat carotid arteries following endothelial denudation injury. At 21 days, perivascular application of TSP-2 siRNA embedded hydrogels significantly downregulated TSP-2 gene expression, cellular proliferation, as well as other associated mediators of IH including MMP-9 and VEGF-R2, ultimately resulting in a significant decrease in IH. Our data illustrates the ability of perivascular CLICK-gelatin delivery of TSP-2 siRNA to mitigate IH following arterial injury.

Vascular injury activates the ELK1/SND1/SRF pathway to promote vascular smooth muscle cell proliferative phenotype and neointimal hyperplasia.

BACKGROUND: Vascular smooth muscle cell (VSMC) proliferation is the leading cause of vascular stenosis or restenosis. Therefore, investigating the molecular mechanisms and pivotal regulators of the proliferative VSMC phenotype is imperative for precisely preventing neointimal hyperplasia in vascular disease. METHODS: Wire-induced vascular injury and aortic culture models were used to detect the expression of staphylococcal nuclease domain-containing protein 1 (SND1). SMC-specific Snd1 knockout mice were used to assess the potential roles of SND1 after vascular injury. Primary VSMCs were cultured to evaluate SND1 function on VSMC phenotype switching, as well as to investigate the mechanism by which SND1 regulates the VSMC proliferative phenotype. RESULTS: Phenotype-switched proliferative VSMCs exhibited higher SND1 protein expression compared to the differentiated VSMCs. This result was replicated in primary VSMCs treated with platelet-derived growth factor (PDGF). In the injury model, specific knockout of Snd1 in mouse VSMCs reduced neointimal hyperplasia. We then revealed that ETS transcription factor ELK1 (ELK1) exhibited upregulation and activation in proliferative VSMCs, and acted as a novel transcription factor to induce the gene transcriptional activation of Snd1. Subsequently, the upregulated SND1 is associated with serum response factor (SRF) by competing with myocardin (MYOCD). As a co-activator of SRF, SND1 recruited the lysine acetyltransferase 2B (KAT2B) to the promoter regions leading to the histone acetylation, consequently promoted SRF to recognize the specific CArG motif, and enhanced the proliferation- and migration-related gene transcriptional activation. CONCLUSIONS: The present study identifies ELK1/SND1/SRF as a novel pathway in promoting the proliferative VSMC phenotype and neointimal hyperplasia in vascular injury, predisposing the vessels to pathological remodeling. This provides a potential therapeutic target for vascular stenosis.

ZFP36L1 controls KLF16 mRNA stability in vascular smooth muscle cells during restenosis after vascular injury.

The RNA-binding zinc finger protein 36 (ZFP36) family participates in numerous physiological processes including transition and differentiation through post-transcriptional regulation. ZFP36L1 is a member of the ZFP36 family. This study aimed to evaluate the role of ZFP36L1 in restenosis. We found that the expression of ZFP36L1 was inhibited in VSMC-phenotypic transformation induced by TGF-ß, PDGF-BB, and FBS and also in the rat carotid injury model. In addition, we found that the overexpression of ZFP36L1 inhibited the proliferation and migration of VSMCs and promoted the expression of VSMC contractile genes; whereas ZFP36L1 interference promoted the proliferation and migration of VSMCs and suppressed the expression of contractile genes. Furthermore, the RNA binding protein immunoprecipitation and double luciferase reporter gene experiments shows that ZFP36L1 regulates the phenotypic transformation of VSMCs through the posttranscriptional regulation of KLF16. Finally, our research results in the rat carotid balloon injury animal model further confirmed that ZFP36L1 regulates the phenotypic transformation of VSMCs through the posttranscriptional regulation of KLF16 and further plays a role in vascular injury and restenosis in vivo.

Blockade of CD47 function attenuates restenosis by promoting smooth muscle cell efferocytosis and inhibiting their migration and proliferation.

Cluster of differentiation 47 (CD47) plays an important role in the pathophysiology of various diseases including atherosclerosis but its role in neointimal hyperplasia which contributes to restenosis has not been studied. Using molecular approaches in combination with a mouse vascular endothelial denudation model, we studied the role of CD47 in injury-induced neointimal hyperplasia. We determined that thrombin-induced CD47 expression both in human aortic smooth muscle cells (HASMCs) and mouse aortic smooth muscle cells. In exploring the mechanisms, we found that the protease-activated receptor 1-Gα protein q/11 (Gαq/11)-phospholipase Cß3-nuclear factor of activated T cells c1 signaling axis regulates thrombin-induced CD47 expression in HASMCs. Depletion of CD47 levels using its siRNA or interference of its function by its blocking antibody (bAb) blunted thrombin-induced migration and proliferation of HASMCs and mouse aortic smooth muscle cells. In addition, we found that thrombin-induced HASMC migration requires CD47 interaction with integrin ß3. On the other hand, thrombin-induced HASMC proliferation was dependent on CD47's role in nuclear export and degradation of cyclin-dependent kinase-interacting protein 1. In addition, suppression of CD47 function by its bAb rescued HASMC efferocytosis from inhibition by thrombin. We also found that vascular injury induces CD47 expression in intimal SMCs and that inhibition of CD47 function by its bAb, while alleviating injury-induced inhibition of SMC efferocytosis, attenuated SMC migration, and proliferation resulting in reduced neointima formation. Thus, these findings reveal a pathological role for CD47 in neointimal hyperplasia.

Bone Morphogenetic Protein-4 Promotes Phenotypic Modulation via SMAD-4/MCT-4 Axis in Vascular Smooth Muscle Cells.

INTRODUCTION: This study aimed to determine whether bone morphogenetic protein-4 (BMP-4), which increases in response to intimal hyperplasia, promotes phenotype transition in vascular smooth muscle cells (VSMCs). METHODS: Balloon injury was used to induce intimal hyperplasia in rats. Hematoxylin-eosin staining was used to detect the alteration of vascular structure. Serum levels of BMP-4 and lactate were detected by ELISA. Human aortic smooth muscle cells (HA-SMCs) were cultured. Protein and mRNA expression levels were detected through Western blot and real-time PCR. Cell migration was measured by transwell assay. RESULTS: Our data showed that serum concentration of BMP-4 was upregulated after balloon injury. Treatment with BMP-4 inhibitor DMH1 (4-(6-(4-isopropoxyphenyl)pyrazolo(1,5-a)pyrimidin-3-yl)quinoline) suppressed the abnormal expression of BMP-4 and inhibited the intimal hyperplasia induced by balloon injury. Compared to BMP-4-negative medium, BMP-4-positive medium was associated with higher synthetic VSMC marker expression levels and lower in contractile gene markers in cultured HA-SMCs. Transfection of monocarboxylic acid transporters-4 (MCT-4) siRNA inhibited the excretion of lactate induced by BMP-4. CONCLUSION: Our analyses provided evidence that BMP-4 and its regulator Smad-4 are key regulators in MCT-4-mediated lactate excretion. This indicates that BMP-4 stimulates the phenotypic transition of VSMCs via SMAD-4/MCT-4 signaling pathway.

Long-term functional outcomes of upper extremity civilian vascular trauma.

OBJECTIVE: Civilian analyses of long-term outcomes of upper extremity vascular trauma (UEVT) are limited. Our goal was to evaluate the management of UEVT in the civilian trauma population and explore the long-term functional consequences. METHODS: A retrospective review and analysis was performed of patients with UEVT at an urban Level 1 trauma center (2001-2022). Management and long-term functional outcomes were analyzed. RESULTS: There were 150 patients with UEVT. Mean age was 34 years, and 85% were male. There were 42% Black and 27% White patients. Mechanism was penetrating in 79%, blunt in 20%, and multifactorial in 1%. Within penetrating trauma, mechanism was from firearms in 30% of cases. Of blunt injuries, 27% were secondary to falls, 13% motorcycle collisions, 13% motor vehicle collisions, and 3% crush injuries. Injuries were isolated arterial in 62%, isolated venous in 13%, and combined in 25% of cases. Isolated arterial injuries included brachial (34%), radial (27%), ulnar (27%), axillary (8%), and subclavian (4%). The majority of arterial injuries (92%) underwent open repair with autologous vein bypass (34%), followed by primary repair (32%), vein patch (6.6%), and prosthetic graft (3.3%). There were 23% that underwent fasciotomies, 68% of which were prophylactic. Two patients were managed with endovascular interventions; one underwent covered stent placement and the other embolization. Perioperative reintervention occurred in 12% of patients. Concomitant injuries included nerves (35%), bones (17%), and ligaments (16%). Intensive care unit admission was required in 45%, with mean intensive care unit length of stay 1.6 days. Mean hospital length of stay was 6.7 days. Major amputation and in-hospital mortality rates were 1.3% and 4.6% respectively. The majority (72%) had >6-month follow-up, with a median follow-up period of 197 days. Trauma readmissions occurred in 19%. Many patients experienced chronic pain (56%), as well as motor (54%) and sensory (61%) deficits. Additionally, 41% had difficulty with activities of daily living. Of previously employed patients (57%), 39% experienced a >6-month delay in returning to work. Most patients (82%) were discharged with opioids; of these, 16% were using opioids at 6 months. CONCLUSIONS: UEVT is associated with long-term functional impairments and opioid use. It is imperative to counsel patients prior to discharge and ensure appropriate follow-up and therapy.

Incidence and characteristics of vascular trauma at a level 2 trauma center.

OBJECTIVE: Despite the significant number of trauma patients treated at level 2 trauma centers (L2TCs) in the United States, most of the literature describing vascular trauma is from level 1 trauma centers (L1TCs). Currently, trauma center designation criteria do not require vascular surgery as a necessary component service. METHODS: A retrospective chart review was performed for all trauma patients with a vascular surgery consultation seen at our L2TC between 2013 and 2018. Patient demographics, injury characteristics, and outcomes were collected and analyzed with descriptive statistics. RESULTS: Of the 3062 trauma patients evaluated at our L2TC, 110 (3.6%) had a vascular surgery consultation. Operative intervention was performed in 35.2% of consults, and 1.0% of all trauma patients had a vascular intervention. Average age was 57 years, and the majority were male (n = 75; 68.2%). Mean Injury Severity Score was 12.0 ± 9.6, and blunt injury (n = 77; 87.5%) was more common than penetrating (n = 11; 12.5%). The most common location of injury was the lower extremity (n = 23; 74.2%), followed by upper extremity (n = 3; 9.7%), chest (n = 2; 6.5%), neck (n = 2; 6.5%), and pelvis (n = 1; 3.2%). Endovascular interventions were performed by the vascular surgery service in 67.7% (n = 21) of all injuries. There was one amputation (3.2%) and one postoperative mortality (3.2%). CONCLUSIONS: At our L2TC, postoperative morbidity and mortality rates at 30 days were substantially lower compared with previously reported data. However, mean injury severity score and the incidence of penetrating and polytrauma were also lower at our institution. Most patients were managed nonoperatively, but when they did require an operation, endovascular therapies were more commonly implemented. Vascular surgery should be considered an integral service in trauma level designation, and there is a need for further investigation of these outcomes in L2TCs.

Vascular complications secondary to resuscitative endovascular balloon occlusion of the aorta placement at a Level 1 Trauma Center.

OBJECTIVE: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is designed to manage severe hemorrhagic shock. Popularized in medical care during military conflicts, the concept has emerged as a lifesaving technique that is utilized around the United States. Literature on risks of REBOA placement, especially vascular injuries, are not well-reported. Our goal was to assess the incidence of vascular injury from REBOA placement and the risk factors associated with injury and death among these patients at our institution. METHODS: We performed a retrospective cohort study of all patients who underwent REBOA placement between September 2017 and June 2022 at our Level 1 Trauma Center. The primary outcome variable was the presence of an injury related to REBOA insertion or use. Secondary outcomes studied were limb loss, the need for dialysis, and mortality. Data were analyzed using descriptive statistics, χ2, and t-tests as appropriate for the variable type. RESULTS: We identified 99 patients who underwent REBOA placement during the study period. The mean age of patients was 43.1 ± 17.2 years, and 67.7% (67/99) were males. The majority of injuries were from blunt trauma (79.8%; 79/99). Twelve of the patients (12.1%; 12/99) had a vascular injury related to REBOA placement. All but one required intervention. The complications included local vessel injury (58.3%; 7/12), distal embolization (16.7%; 2/12), excessive bleeding requiring vascular consult (8.3%; 1/12), pseudoaneurysm requiring intervention (8.3%; 1/12), and one incident of inability to remove the REBOA device (8.3%; 1/12). The repairs were performed by vascular surgery (75%; 9/12), interventional radiology (16.7%; 2/12), and trauma surgery (8.3%; 1/12). There was no association of age, gender, race, and blunt vs penetrating injury to REBOA-related complications. Mortality in this patient population was high (40.4%), but there was no association with REBOA-related complications. Ipsilateral limb loss occurred in two patients with REBOA-related injuries, but both were due to their injuries and not to REBOA-related ischemia. CONCLUSIONS: Although vascular complications are not unusual in REBOA placement, there does not appear to be an association with limb loss, dialysis, or mortality if they are addressed promptly. Close coordination between vascular surgeons and trauma surgeons is essential in patients undergoing REBOA placement.

Long-term outcomes of autologous vein bypass for repair of upper and lower extremity major arterial trauma.

OBJECTIVE: Autologous vein is the preferred bypass conduit for extremity arterial injuries owing to superior patency and low infection risk; however, long-term data on outcomes in civilians are limited. Our goal was to assess short- and long-term outcomes of autologous vein bypass for upper and lower extremity arterial trauma. METHODS: A retrospective review was performed of patients with major extremity arterial injuries (2001-2019) at a level I trauma center. Demographics, injury and intervention details, and outcomes were recorded. Primary outcomes were primary patency at 1 year and 3 years. Secondary outcomes were limb function at 6 months, major amputation, and mortality. Multivariable analysis determined risk factors for functional impairment. RESULTS: There were 107 extremity arterial injuries (31.8% upper and 68.2% lower) treated with autologous vein bypass. Mechanism was penetrating in 77% of cases, of which 79.3% were due to firearms. The most frequently injured vessels were the common and superficial femoral (38%), popliteal (30%), and brachial arteries (29%). For upper extremity trauma, concomitant nerve and orthopedic injuries were found in 15 (44.1%) and 11 (32.4%) cases, respectively. For lower extremities, concomitant nerve injuries were found in 10 (13.7%) cases, and orthopedic injuries in 31 (42.5%). Great saphenous vein was the conduit in 96% of cases. Immediate intraoperative bypass revision occurred in 9.3% of patients, most commonly for graft thrombosis. The in-hospital return to operating room rate was 15.9%, with graft thrombosis (47.1%) and wound infections (23.5%) being the most common reasons. The median follow-up was 3.6 years. Kaplan-Meier analysis showed 92% primary patency at 1 year and 90% at 3 years. At 6 months, 36.1% of patients had functional impairment. Of patients with functional impairment at 6 months, 62.9% had concomitant nerve and 60% concomitant orthopedic injuries. Of those with nerve injury, 91.7% had functional impairment, compared with 17.8% without nerve injury (P < .001). Of patients with orthopedic injuries, 51.2% had functional impairment, vs 25% of those without orthopedic injuries (P = .01). On multivariable analysis, concomitant nerve injury (odds ratio, 127.4; 95% confidence interval, 17-957; P <. 001) and immediate intraoperative revision (odds ratio, 11.03; 95% confidence interval, 1.27-95.55; P = .029) were associated with functional impairment. CONCLUSIONS: Autologous vein bypass for major extremity arterial trauma is durable; however, many patients have long-term limb dysfunction associated with concomitant nerve injury and immediate intraoperative bypass revision. These factors may allow clinicians to identify patients at higher risk for functional impairment, to outline patient expectations and direct rehabilitation efforts toward improving functional outcomes.

The impact of urgency of repair on outcomes following thoracic endovascular aortic repair for blunt thoracic aortic injury.

OBJECTIVE: Current societal recommendations regarding the timing of thoracic endovascular aortic repair (TEVAR) for blunt thoracic aortic injury (BTAI) vary. Prior studies have shown that elective repair was associated with lower mortality after TEVAR for BTAI. However, these studies lacked data such as Society for Vascular Surgery (SVS) aortic injury grades and TEVAR-related postoperative outcomes. Therefore, we used the Vascular Quality Initiative registry, which includes relevant anatomic and outcome data, to examine the outcomes following urgent/emergent (≤ 24 hours) vs elective TEVAR for BTAI. METHODS: Patients undergoing TEVAR for BTAI between 2013 and 2022 were included, excluding those with SVS grade 4 aortic injuries. We included covariates such as age, sex, race, transfer status, body mass index, preoperative hemoglobin, comorbidities, medication use, SVS aortic injury grade, coexisting injuries, Glasgow Coma Scale, and prior aortic surgery in a regression model to compute propensity scores for assignment to urgent/emergent or elective TEVAR. Perioperative outcomes and 5-year mortality were evaluated using inverse probability-weighted logistic regression and Cox regression, also adjusting for left subclavian artery revascularization/occlusion and annual center and physician volumes. RESULTS: Of 1016 patients, 102 (10%) underwent elective TEVAR. Patients who underwent elective repair were more likely to undergo revascularization of the left subclavian artery (31% vs 7.5%; P < .001) and receive intraoperative heparin (94% vs 82%; P = .002). After inverse probability weighting, there was no association between TEVAR timing and perioperative mortality (elective vs urgent/emergent: 3.9% vs 6.6%; odds ratio [OR], 1.1; 95% confidence interval [CI], 0.27-4.7; P = .90) and 5-year mortality (5.8% vs 12%; hazard ratio [HR], 0.95; 95% CI, 0.21-4.3; P > .9).Compared with urgent/emergent TEVAR, elective repair was associated with lower postoperative stroke (1.0% vs 2.1%; adjusted OR [aOR], 0.12; 95% CI, 0.02-0.94; P = .044), even after adjusting for intraoperative heparin use (aOR, 0.12; 95% CI, 0.02-0.92; P = .042). Elective TEVAR was also associated with lower odds of failure of extubation immediately after surgery (39% vs 65%; aOR, 0.18; 95% CI, 0.09-0.35; P < .001) and postoperative pneumonia (4.9% vs 11%; aOR, 0.34; 95% CI, 0.13-0.91; P = .031), but comparable odds of any postoperative complication as a composite outcome and reintervention during index admission. CONCLUSIONS: Patients with BTAI who underwent elective TEVAR were more likely to receive intraoperative heparin. Perioperative mortality and 5-year mortality rates were similar between the elective and emergent/urgent TEVAR groups. Postoperatively, elective TEVAR was associated with lower ischemic stroke, pulmonary complications, and prolonged hospitalization. Future modifications in society guidelines should incorporate the current evidence supporting the use of elective TEVAR for BTAI. The optimal timing of TEVAR in patients with BTAI and the factors determining it should be the subject of future study to facilitate personalized decision-making.

Surgeon volume and outcomes following thoracic endovascular aortic repair for blunt thoracic aortic injury.

OBJECTIVE: Thoracic endovascular aortic repair (TEVAR) for blunt thoracic aortic injury (BTAI) at high-volume hospitals has previously been associated with lower perioperative mortality, but the impact of annual surgeon volume on outcomes following TEVAR for BTAI remains unknown. METHODS: We analyzed Vascular Quality Initiative (VQI) data from patients with BTAI that underwent TEVAR between 2013 and 2023. Annual surgeon volumes were computed as the number of TEVARs (for any pathology) performed over a 1-year period preceding each procedure and were further categorized into quintiles. Surgeons in the first volume quintile were categorized as low volume (LV), the highest quintile as high volume (HV), and the middle three quintiles as medium volume (MV). TEVAR procedures performed by surgeons with less than 1-year enrollment in the VQI were excluded. Using multilevel logistic regression models, we evaluated associations between surgeon volume and perioperative outcomes, accounting for annual center volumes and adjusting for potential confounders, including aortic injury grade and severity of coexisting injuries. Multilevel models accounted for the nested clustering of patients and surgeons within the same center. Sensitivity analysis excluding patients with grade IV BTAI was performed. RESULTS: We studied 1321 patients who underwent TEVAR for BTAI (28% by LV surgeons [0-1 procedures per year], 52% by MV surgeons [2-8 procedures per year], 20% by HV surgeons [≥9 procedures per year]). With higher surgeon volume, TEVAR was delayed more (in <4 hours: LV: 68%, MV: 54%, HV: 46%; P < .001; elective (>24 hours): LV: 5.1%; MV: 8.9%: HV: 14%), heparin administered more (LV: 80%, MV: 81%, HV: 87%; P = .007), perioperative mortality appears lower (LV: 11%, MV: 7.3%, HV: 6.5%; P = .095), and ischemic/hemorrhagic stroke was lower (LV: 6.5%, MV: 3.6%, HV: 1.5%; P = .006). After adjustment, compared with LV surgeons, higher volume surgeons had lower odds of perioperative mortality (MV: 0.49; 95% confidence interval [CI], 0.25-0.97; P = .039; HV: 0.45; 95% CI, 0.16-1.22; P = .12; MV/HV: 0.50; 95% CI, 0.26-0.96; P = .038) and ischemic/hemorrhagic stroke (MV: 0.38; 95% CI, 0.18-0.81; P = .011; HV: 0.16; 95% CI, 0.04-0.61; P = .008). Sensitivity analysis found lower adjusted odds for perioperative mortality (although not significant) and ischemic/hemorrhagic stroke for higher volume surgeons. CONCLUSIONS: In patients undergoing TEVAR for BTAI, higher surgeon volume is independently associated with lower perioperative mortality and postoperative stroke, regardless of hospital volume. Future studies could elucidate if TEVAR for non-ruptured BTAI might be delayed and allow stabilization, heparinization, and involvement of a higher TEVAR volume surgeon.

Role of CaMKII in diabetes induced vascular injury and its interaction with anti-diabetes therapy.

Diabetes mellitus is a metabolic disorder denoted by chronic hyperglycemia that drives maladaptive structural changes and functional damage to the vasculature. Attenuation of this pathological remodeling of blood vessels remains an unmet target owing to paucity of information on the metabolic signatures of this process. Ca2+/calmodulin-dependent kinase II (CaMKII) is expressed in the vasculature and is implicated in the control of blood vessels homeostasis. Recently, CaMKII has attracted a special attention in view of its chronic upregulated activity in diabetic tissues, yet its role in the diabetic vasculature remains under investigation.This review highlights the physiological and pathological actions of CaMKII in the diabetic vasculature, with focus on the control of the dialogue between endothelial (EC) and vascular smooth muscle cells (VSMC). Activation of CaMKII enhances EC and VSMC proliferation and migration, and increases the production of extracellular matrix which leads to maladaptive remodeling of vessels. This is manifested by activation of genes/proteins implicated in the control of the cell cycle, cytoskeleton organization, proliferation, migration, and inflammation. Endothelial dysfunction is paralleled by impaired nitric oxide signaling, which is also influenced by CaMKII signaling (activation/oxidation). The efficiency of CaMKII inhibitors is currently being tested in animal models, with a focus on the genetic pathways involved in the regulation of CaMKII expression (microRNAs and single nucleotide polymorphisms). Interestingly, studies highlight an interaction between the anti-diabetic drugs and CaMKII expression/activity which requires further investigation. Together, the studies reviewed herein may guide pharmacological approaches to improve health-related outcomes in patients with diabetes.

Mast cell activation and degranulation in acute artery injury: A target for post-operative therapy.

The increasing incidence of cardiovascular disease (CVD) has led to a significant ongoing need to address this surgically through coronary artery bypass grafting (CABG) and percutaneous coronary interventions (PCI). From this, there continues to be a substantial burden of mortality and morbidity due to complications arising from endothelial damage, resulting in restenosis. Whilst mast cells (MC) have been shown to have a causative role in atherosclerosis and other vascular diseases, including restenosis due to vein engraftment; here, we demonstrate their rapid response to arterial wire injury, recapitulating the endothelial damage seen in PCI procedures. Using wild-type mice, we demonstrate accumulation of MC in the femoral artery post-acute wire injury, with rapid activation and degranulation, resulting in neointimal hyperplasia, which was not observed in MC-deficient KitW-sh/W-sh mice. Furthermore, neutrophils, macrophages, and T cells were abundant in the wild-type mice area of injury but reduced in the KitW-sh/W-sh mice. Following bone-marrow-derived MC (BMMC) transplantation into KitW-sh/W-sh mice, not only was the neointimal hyperplasia induced, but the neutrophil, macrophage, and T-cell populations were also present in these transplanted mice. To demonstrate the utility of MC as a target for therapy, we administered the MC stabilizing drug, disodium cromoglycate (DSCG) immediately following arterial injury and were able to show a reduction in neointimal hyperplasia in wild-type mice. These studies suggest a critical role for MC in inducing the conditions and coordinating the detrimental inflammatory response seen post-endothelial injury in arteries undergoing revascularization procedures, and by targeting the rapid MC degranulation immediately post-surgery with DSCG, this restenosis may become a preventable clinical complication.

A rare vascular injury in a blood donor after whole blood donation.

BACKGROUND: Blood donation is a safe process though reactions may still occur. We describe a rare vascular complication in a frequent donor, with improvements in the collection process aimed at avoiding future events. METHODS: A 63-year-old woman presented with local pain and an apparent collection in the left arm 8 days after donation. Duplex ultrasound identified a superficial liquid collection and signs of arteriovenous fistula (AVF) between the cubital vein and an arterial branch. A computed tomography (CT)-angio performed 1 day after ultrasound did not identify signs of AVF, followed by a new duplex which confirmed CT-angio findings. It was assumed that a traumatic AVF evolved with spontaneous thrombosis. In the early follow-up (18 days), a progressive regression of hematoma was observed without any sequelae. RESULTS: Investigation showed a faster whole blood bag collection time (3 min; normal: 5-9 min), and the processed packed red blood cell had a brighter red color than usual. The donor reported local bleeding after needle withdrawal, not observed in previous donations and a bruise forming on the same day. No arterial puncture (AP) was noticed by the collection staff during the procedure. The staff was retrained and actions were taken focusing on more active surveillance of late reactions, highlighting the importance of post-donation information by the donors, regardless of any adverse reaction observed, to detect late complications. CONCLUSION: We described an uncommon AP in a donor that was not identified, leading to an AVF that spontaneously thrombosed.

Liquid plasma promotes angiogenesis through upregulation of endothelial nitric oxide synthase-induced extracellular matrix metabolism: potential applications of liquid plasma for vascular injuries.

BACKGROUND: Applications of nonthermal plasma have expanded beyond the biomedical field to include antibacterial, anti-inflammatory, wound healing, and tissue regeneration. Plasma enhances epithelial cell repair; however, the potential damage to deep tissues and vascular structures remains under investigation. RESULT: This study assessed whether liquid plasma (LP) increased nitric oxide (NO) production in human umbilical vein endothelial cells by modulating endothelial NO synthase (eNOS) phosphorylation and potential signaling pathways. First, we developed a liquid plasma product and confirmed the angiogenic effect of LP using the Matrigel plug assay. We found that the NO content increased in plasma-treated water. NO in plasma-treated water promoted cell migration and angiogenesis in scratch and tube formation assays via vascular endothelial growth factor mRNA expression. In addition to endothelial cell proliferation and migration, LP influenced extracellular matrix metabolism and matrix metalloproteinase activity. These effects were abolished by treatment with NG-L-monomethyl arginine, a specific inhibitor of NO synthase. Furthermore, we investigated the signaling pathways mediating the phosphorylation and activation of eNOS in LP-treated cells and the role of LKB1-adenosine monophosphate-activated protein kinase in signaling. Downregulation of adenosine monophosphate-activated protein kinase by siRNA partially inhibited LP-induced eNOS phosphorylation, angiogenesis, and migration. CONCLUSION: The present study suggests that LP treatment may be a novel strategy for promoting angiogenesis in vascular damage. Video Abstract.

Understanding large vessel perforation requiring treatment with covered stent implantation: A case series.

Large vessel perforation during coronary intervention is a rare but potentially fatal complication, often requiring implantation of a covered stent for resolution. While technology is improving, the long-term patency of covered stents is less than drug-eluting stents, and implantation of covered stents should be used sparingly. Large vessel perforations are complex and often the perforation inflow is not located at the site of extravasation seen on angiography. This can lead to geographic miss when implanting covered stents and necessitate the implantation of additional covered stents which increases the risk for short- and long-term complications. We present a case series to further investigate the anatomy and mechanism of large vessel perforations and guidance on effective covered stent implantation.

Dihydroartemisinin inhibits restenosis after balloon angioplasty via circHSPA4/miR-19a-5p axis.

Dihydroartemisinin (DHA) inhibits restenosis following balloon angioplasty. However, data on the mechanisms of DHA activity in restenosis remains scant. Here, we investigated the role of circRNAs in mediating the inhibitory activity of DHA in neointimal formation. We used total RNA sequencing data to profile the expression of mRNA, circRNA and small RNA in sham, vascular balloon injury (VBI) and DHA-treated groups. CCK8 and EdU assays were employed to analyze cell proliferation, while qRT-PCR and Western blot were used to analyze the RNA or protein expression. In addition, we used RNA immunoprecipitation and luciferase reporter assay to assess the binding of circHSPA4 with miR-19a-5p. RNA sequencing demonstrated that circHSPA4 was upregulated in VBI. Treatment with DHA effectively suppressed the upregulation of the circHSPA4. In addition, analysis of platelet-derived growth family factor bb (PDGFbb)-induced HA-VSMCs showed upregulation of circHSPA4, which was associated with cell proliferation and differentiation. CircHSPA4 was shown to induce dedifferentiation and proliferation of smooth muscle cells. PDGFBB-induced overexpression of CircHSPA4 in HA-VSMCs led to suppression of miR-19a-5p, a phenomenon that was reversed by DHA, in concentration-dependent fashion. In addition, miR-19a-5p reduced the dedifferentiation and proliferation of the smooth muscle cells. Our data demonstrated that CircHSPA4 regulates proliferation and differentiation of smooth muscle cells. DHA and miR-19a-5p modulates CircHSPA4 and can be used as coated drugs on balloon catheter to improve the success rate of vascular remodeling.

Extracellular Matrix Remodeling in Vascular Disease: Defining Its Regulators and Pathological Influence.

Because of structural and cellular differences (ie, degrees of matrix abundance and cross-linking, mural cell density, and adventitia), large and medium-sized vessels, in comparison to capillaries, react in a unique manner to stimuli that induce vascular disease. A stereotypical vascular injury response is ECM (extracellular matrix) remodeling that occurs particularly in larger vessels in response to injurious stimuli, such as elevated angiotensin II, hyperlipidemia, hyperglycemia, genetic deficiencies, inflammatory cell infiltration, or exposure to proinflammatory mediators. Even with substantial and prolonged vascular damage, large- and medium-sized arteries, persist, but become modified by (1) changes in vascular wall cellularity; (2) modifications in the differentiation status of endothelial cells, vascular smooth muscle cells, or adventitial stem cells (each can become activated); (3) infiltration of the vascular wall by various leukocyte types; (4) increased exposure to critical growth factors and proinflammatory mediators; and (5) marked changes in the vascular ECM, that remodels from a homeostatic, prodifferentiation ECM environment to matrices that instead promote tissue reparative responses. This latter ECM presents previously hidden matricryptic sites that bind integrins to signal vascular cells and infiltrating leukocytes (in coordination with other mediators) to proliferate, invade, secrete ECM-degrading proteinases, and deposit injury-induced matrices (predisposing to vessel wall fibrosis). In contrast, in response to similar stimuli, capillaries can undergo regression responses (rarefaction). In summary, we have described the molecular events controlling ECM remodeling in major vascular diseases as well as the differential responses of arteries versus capillaries to key mediators inducing vascular injury.