Endovascular Denervation for the Improvement of Limb Ischemia in Patients with Peripheral Artery Disease: A Randomized Clinical Trial.

BACKGROUND: To evaluate the safety and efficacy of endovascular denervation (EDN) as an adjunct to percutaneous vascular intervention (PVI) for peripheral artery disease (PAD). METHODS: From August 2019 to April 2021, 38 eligible patients with PAD enrolled in this study were randomly and equally assigned into 2 groups: the PVI group and the PVI + EDN group treated with EDN at the iliac and femoral arteries before PVI. The primary endpoint was the improvement in the ankle brachial index at 6 months after the procedure. The secondary endpoints were transcutaneous oxygen pressure (TcPO2), Rutherford category, numerical rating scale score, and safety. RESULTS: The technical success rates of PVI and EDN were 100%, and no device-related or procedure-related major adverse events occurred in either group. Compared with PVI alone, PVI + EDN demonstrated a significant improvement in limb hemodynamics at 6 months (Δ ankle brachial index 0.44 ± 0.31 vs. 0.24 ± 0.15, P = 0.018). Microcirculatory perfusion of PAD was significantly better at 6 months in the PVI + EDN group (ΔTcPO2, 15.68 ± 16.72 vs. 4.95 ± 13.43, P = 0.036). The Rutherford category was significantly improved in the PVI + EDN group in comparison with the PVI group at the 3-month follow-up (100.00% vs. 68.42%, P = 0.02). The decrease in the numerical rating scale score in the PVI + EDN group was greater than that in the PVI group at 1 week following the procedure (3 [2-5] vs. 4 [4-6], P = 0.022). CONCLUSIONS: In this single-center pilot analysis of a heterogeneous cohort of patients with PAD, PVI with EDN demonstrated a significant improvement in limb ischemia at 6 months compared with PVI alone.

Bone marrow mesenchymal stem cellsderived exosomes stabilize atherosclerosis through inhibiting pyroptosis.

OBJECTIVES: This study aimed to determine the effects of bone marrow mesenchymal stem cells (BMSCs)-derived exosomes (BMSC-EXO) on atherosclerosis (AS), and its related underlying mechanisms. METHODS: Exosomes were isolated from mouse BMSCs, and identified by transmission electron microscopy (TEM), Nanosight (NTA), and western blot. A mouse AS model was established, and exosomes were injected into the tail vein. Total cholesterol (TC) and triglycerides (TG) were detected using their corresponding assay kits. The contents of IL-1ß and IL-18 in serum were detected by ELISA. The mRNA and protein expression levels of GSDMD, Caspase1, and NLRP3 were detected by qRT-PCR and Western blot. Finally, aortic tissues in the Model and BMSC-EXO groups were sent for sequencing. RESULTS: TEM, NTA, and western blot indicated successful isolation of exosomes. Compared with the control group, the TC, TG contents, IL-1ß and IL-18 concentrations of the mice in the Model group were significantly increased; nonetheless, were significantly lower after injected with BMSC-EXO than those in the Model group (p < 0.05). Compared with the control group, the expressions of NLRP3, caspase-1 and GSDMD were significantly up-regulated in the Model group (p < 0.05), while the expressions of NLRP3, caspase-1, and GSDMD were significantly down-regulated by BMSC-EXO. By sequencing, a total of 3852 DEGs were identified between the Model and BMSC-EXO group and were significantly enriched in various biological processes and pathways related to mitochondrial function, metabolism, inflammation, and immune response. CONCLUSION: AS can induce pyroptosis, and BMSC-EXO can reduce inflammation and alleviate the progression of AS by inhibiting NLRP3/Caspase-1/GSDMD in the pyroptosis pathway.

Placement of Bare Self-Expanding Metal Stent for Isolated Superior Mesenteric Artery Dissection.

BACKGROUND: To evaluate the safety and efficacy of placing bare self-expanding metal stent (SEMS) for treating isolated superior mesenteric artery dissection (ISMAD). METHOD: Patients with ISMAD who received bare SEMS from January 2014 to December 2021 at the authors' center were included. Baseline characteristics, clinical manifestation, radiological findings, and treatment outcomes, including symptom relief and SMA remodeling, were analyzed. RESULT: A total of 26 patients were included in this study. Among the patients, 25 were admitted due to persistent abdominal pain, and 1 was admitted based on computed tomography angiography (CTA) during physical examination. According to CTA scan, the percentage of stenosis was 91% (53.8-100%), and the length of dissection was 100.2 ± 8.4 mm. All patients received bare SEMS placement. The median time to symptom relief was 1 day (interquartile range, 1 3 days). The the median follow-up time of CTA was 6.8 months (range, 2-85 months), with an average of 16.2 months. Complete remodeling of the superior mesenteric artery (SMA) was recorded in 24 patients. The median time to remodeling was 3 months with an average of 4.7 months. Survival analysis indicated no significance difference in remodeling time between different ISMAD types based on Yun classification (P = 0.888) or between acute and nonacute disease (P = 0.423). Incomplete remodeling was noted in 2 patients. Distal stent occlusion without SMA-related symptoms was seen in 1 patient. Proximal stent stenosis occurred in 1 patient, and restenting was performed. The median follow-up time by telephone was 20.8 (4-91.5) months, and no intestinal ischemic symptoms were observed in any patient. CONCLUSIONS: Bare SEMS placement can effectively relieve SMA-related symptoms in a short time and promote dissection remodeling in ISMAD. Time from symptom onset and classification of ISMAD seem not to have effects on SMA remodeling after bare SEMS placement.

Risk Factors for Access-Related Adverse Events Related to the Preclose Technique in Thoracic Endovascular Aortic Repair.

PURPOSE: To analyze the risk factors for access-related adverse events (AEs) of the preclose technique in thoracic endovascular aortic repair (TEVAR). MATERIALS AND METHODS: Ninety-one patients with Stanford type B aortic dissection who underwent the preclose technique in TEVAR between January 2013 and December 2021 were included. According to the occurrence of access-related AEs, the patients were divided into 2 groups: those with AE and those without AE. Age, sex, combined diseases, body mass index, skin depth, femoral artery diameter, access calcification, iliofemoral artery tortuosity, and sheath size were recorded for risk factor analysis. The sheath-to-femoral artery ratio (SFAR), the ratio of the femoral artery inner diameter (in millimeters) to the sheath's outer diameter (in millimeters), was also included in the analysis. RESULTS: SFAR was identified as an independent risk factor for AEs using multivariable logistic analysis (odds ratio, 251.748; 95% CI, 7.004-9,048.534; P = .002). The cutoff value of SFAR was 0.85 and was related to a higher incidence of access-related AEs (5.2% vs 33.3%, P = .001), especially to a higher stenosis rate (0.0% vs 21.2%, P = .001). CONCLUSIONS: SFAR is an independent risk factor for access-related AEs of preclose in TEVAR with a cutoff value of 0.85. SFAR could be a new criterion for preoperative access evaluation in high-risk patients that may allow the detection and treatment of access-related AEs at the early stage.

Biodegradable PTX-PLGA-coated magnesium stent for benign esophageal stricture: An experimental study.

Biodegradable stents can degrade step by step and thereby avoid secondary removal by endoscopic procedures in contrast to metal stents. Herein, a biodegradable composite stent, a magnesium (Mg)-based braided stent with a surface coating of poly (lactic-co-glycolic acid) (PLGA) containing paclitaxel (PTX), was designed and tested. By adding this drug-loaded polymer coating, the radial force of the stent increased from 33 Newton (N) to 83 N. PTX was continuously released as the stent degraded, and the in vitro cumulative drug release in phosphate-buffered saline for 28 days was 115 ± 13.5 µg/mL at pH = 7.4 and 176 ± 12 µg/mL at pH = 4.0. There was no statistically significant difference in the viability of fibroblasts of stent extracts with different concentration gradients (P > 0.05), while the PTX-loaded stents effectively promoted fibroblast apoptosis. In the animal experiment, the stents were able to maintain esophageal patency during the 3-week follow-up and to reduce the infiltration of inflammatory cells and the amount of fibrous tissue. These results showed that the PTX-PLGA-coated Mg stent has the potential to be a safe and effective approach for benign esophageal stricture. STATEMENT OF SIGNIFICANCE: We designed a biodegradable composite stent, having poly (lactic-co-glycolic acid) (PLGA) containing paclitaxel (PTX) coated the surface of the magnesium (Mg)-based braided stent. We evaluated in vitro and in vivo characteristics of the Mg esophageal stent having a PLGA coating plus a variable concentration of PTX in comparison with the absence of PTX PLGA coating. The PTX PLGA stents exerted higher radial force than stents without coating, degraded more quickly in an acid medium, and effectively promoted fibroblast apoptosis in vitro experiments. In a rabbit model of caustic-induced esophageal stricture, there was an increased lumen and decreased inflammation of the esophageal wall in the animals stented with PTX-PLGA versus the sham group, indicating a potential approach for benign esophageal stricture.

Iron Together with Lipid Downregulates Protein Levels of Ceruloplasmin in Macrophages Associated with Rapid Foam Cell Formation.

AIM: Iron accumulation in foam cells was previously shown to be involved in atherogenesis. However, the mechanism for iron accumulation was not clarified. Ceruloplasmin (Cp) is an important factor in cellular iron efflux and was found to be downregulated in atherosclerotic plaques in our previous study. The current study is to investigate the role of Cp in atherosclerosis. METHODS: We used RAW264.7 cells, a well-accepted cell model of atherosclerosis, which were treated with lipopolysaccharides (LPS), ferric ammonium citrate (FAC) or deferoxamine, and oxidized low density lipoprotein (ox-LDL) to detect the regulation of Cp and its influence in iron efflux and lipid accumulation using biochemical and histological assays. RESULTS: Our results showed that the Cp protein level increased after 200-µM FAC treatment in LPS-activated RAW264.7 cells. Ox-LDL treatment (50 µg/ml) moderately reduced both mRNA and protein levels and ferroxidase activity of Cp (p＜0.05). No significant difference was observed in the expression of ferritin and ferroportin, two important iron-related proteins for iron storage and efflux, respectively, after ox-LDL treatment. However, co-treatment with ox-LDL and FAC drastically reduced the expression of Cp. Accordingly, the ferroxidase activities simultaneously decreased, whereas the protein levels of Ft and Fpn1 significantly increased, indicating further iron accumulation. Moreover, co-treatment with FAC and ox-LDL enhanced the accumulation of cholesterol compared with ox-LDL-only treatment to trigger apoptosis. CONCLUSION: Our findings suggest that physiological interaction of iron and lipid obstructs iron efflux and accelerates the lipid accumulation in macrophages during foam cell formation, which implicates the role of iron in the pathology of atherosclerosis.

[Testing the influence of lipid laden and iron-overloading on ceruloplasmin expression in RAW 264.7 cells].

OBJECTIVE: To investigate whether the treatment of oxidized low density lipoprotein (ox-LDL) could reduce ceruloplasmin (Cp) expression and then, influence iron efflux in macrophages. METHODS: RAW264.7 cells were treated by lipopolysaccharides (LPS), ferric ammonium citrate (FAC), deferoxamine (DFO) and ox-LDL. Biochemical analysis and histological assays were performed to detect the iron-related protein including ferritin (Ft), transferrin receptor (TfR), ferroportin 1 (FPN1) and Cp. And the cholesterol enzyme was used to evaluate cells' cholesterol content. RESULTS: Western blot showed that protein level of FPN1, Ft increased and protein level of TfR decreased after the treatment of FAC. The mRNA level (t=-5.995, P=0.019) and the oxidative activity (t=-9.875, P=0.001) of Cp increased significantly after the treatment of LPS+FAC compared to control group. The treatment of ox-LDL could reduce protein level of Cp compared to LPS treated cells and no different protein levels of Ft and Ferroportin was found after the treatment of ox-LDL as shown by Western blot. The protein level, ferroxidase activities (t=6.663, P=0.003) and mRNA levels (t=8.948, P=0.001) of Cp in LPS+ox-LDL+FAC group were reduced than LPS+FAC group. The protein levels of Ft and FPN1 in LPS+ox-LDL+FAC group was significant higher than LPS+FAC group as shown by Western blot. CONCLUSION: The findings suggest that the expression of Cp is reduced in foam cells and leads to obstructed iron efflux in iron overloaded foam cells.

Mitochondrion-Targeted Peptide SS-31 Inhibited Oxidized Low-Density Lipoproteins-Induced Foam Cell Formation through both ROS Scavenging and Inhibition of Cholesterol Influx in RAW264.7 Cells.

Foam cell formation as a result of imbalance of modified cholesterol influx and efflux by macrophages is a key to the occurrence and development of atherosclerosis. Oxidative stress is thought to be involved in the pathogenesis of atherosclerosis. SS-31 is a member of the Szeto-Schiller (SS) peptides shown to specifically target the inner mitochondrial membrane to scavenge reactive oxygen species. In this study, we investigated whether SS-31 may provide protective effect on macrophage from foam cell formation in RAW264.7 cells. The results showed that SS-31 inhibited oxidized low-density lipoproteins (ox-LDL)-induced foam cell formation and cholesterol accumulation, demonstrated by intracellular oil red O staining and measurement of cholesterol content. The mechanism was revealed that SS-31 did not only significantly attenuated ox-LDL-induced generation of reactive oxygen species (ROS) and increased the activities of superoxide dismutases, but also dose-dependently inhibited the expression of CD36 and LOX-1, two scavenger receptors of ox-LDL, while the expression of ATP-binding cassette A1 and G1, playing a pivotal role in cholesterol efflux, was not affected. As a result, SS-31 decreased pro-inflammatory cytokines such as interleukin 6 and tumor necrosis factor alpha, suggesting the prevention of inflammatory responses. In conclusion, our results demonstrate that SS-31 provides a beneficial effect on macrophages from foam cell formation, likely, through both ROS scavenging and inhibition of cholesterol influx. Therefore, SS-31 may potentially be of therapeutic relevance in prevention of human atherogenesis.

Low expression of ferroxidases is implicated in the iron retention in human atherosclerotic plaques.

The effect of iron on the progress of atherosclerosis is still controversial. To explore the relationship between atherosclerotic plaques and iron metabolism and how iron is accumulated in plaque macrophages, we performed Oil red O staining to detect the lipid of the atherosclerotic plaques, enzyme-linked immunosorbent assay to detect the intracellular lipids (total cholesterol, free cholesterol) and serum hepcidin, Western-blot to examine the iron-related proteins, immunohistochemical and immunofluorescence assays to localize ferroportin 1 in macrophages. The contents of serum iron and transferrin saturation were measured. The results confrimed that atherosclerotic plaques were all lipid-rich. Compared to normal vessel wall, atherosclerotic plaques had significantly higher levels of ferritin and ferroportin 1. Strikingly, we found the much lower levels of ferroxidases ceruloplasmin and hephaestin in plaque tissue than the normal vessel, while the content of serum hepcidin, iron and transferrin saturation were similar in these two groups. The novel finding suggests that the inability of ferrous iron to be oxidized into ferric iron might be a potential mechanism for iron retention in plaques.