Evaluation of systemic immune-inflammation index for predicting severity of lower extremity arterial disease

OBJECTIVE

Predictive value of systemic immune-inflammation index (SII) has been shown in clinical outcomes and complexity of coronary artery disease, acute coronary syndrome, and heart failure. We sight to evaluate value of SII in patients with lower extremity arterial disease (LEAD).

METHODS

A total of 271 patients diagnosed with LEAD were included to our study. Blood samples of the patients were collected and analyzed for biochemical variables and complete blood count parameters. SII value of each patient was calculated. The complexity of atherosclerotic disease was classified according to Trans-Atlantic Inter-Society Consensus (TASC II) classification.

RESULTS

Patients with TASC C-D were older than patients in TASC A-B group (63.06 ± 9.24 years and 60.85 ± 8.75 years, respectively). Other co-morbidities were comparable in both groups. Hemoglobin level and lymphocyte count were significantly lower, neutrophil, platelet counts, and SII values were significantly higher in patients with TASC C-D disease compared to that of patients with TASC A-B disease. SII showed significant correlation with the severity of LEAD (r = 0.363, p < .001). SII value of 664.24 predicted TASC C-D disease with a sensitivity and specificity of 60.8% and 73.3%, respectively. Results of multivariate logistic regression analysis showed that SII had higher odds ratio compared to platelet, neutrophil, and lymphocyte counts.

CONCLUSION

Higher SII may indicate probability of more complex LEAD. This relationship seems plausible in terms of similar pathophysiology of coronary artery disease and peripheral artery disease.

An evaluation of inflammatory and endothelial dysfunction markers as determinants of peripheral arterial disease in those with diabetes mellitus

The most serious long-term effects of diabetes is peripheral artery disease (PAD) which increases the chance of developing diabetic foot ulcers, gangrene and even lower limb amputation. The clinical manifestations of PAD which are typically not revealed until symptoms like intermittent claudication, rest pain and ischemic gangrene develop, are not present in majority of diabetes mellitus patients with PAD due to diabetic peripheral neuropathy. Therefore, current study is aimed to evaluate the inflammatory and endothelial dysfunction markers with their correlation to biomarkers that can help for in-time diagnosis and efficient prognosis of developing diabetes-associated PAD. Enzyme-linked immunosorbent assay was used to evaluate the interlukin-6, interlukin-8, intercellular adhesion molecule (ICAM) and vascular cell adhesion molecule (VCAM) in PAD with diabetes group, diabetic group and healthy individual group while biomarkers were measured by kit method. It was observed that serum IL-6, IL-8, ICAM and VCAM levels in type II diabetes mellitus (T2DM) with PAD patients were increased significantly (85.93, 597.08, 94.80 and 80.66) as compared to T2DM patients (59.52, 231.34, 56.88 and 50.19) and healthy individuals (4.81, 16.93, 5.55 and 5.16). The overall means for the parameters, IL-6, IL-8, ICAM, VCAM, urea, S/creatinine, CK-MB, AST, ALT, cholesterol, triglyceride, HDL, LDL, PT, aPTT, INR, HbA1C, and CRP within all groups were significantly (P < 0.05) different from each other. Therefore, it was concluded that the change in IL-6, IL-8, ICAM and VCAM can serve as an accurate diagnostic indicator and successful treatment.

Alginate-Encapsulated Mesenchymal Stromal Cells Improve Hind Limb Ischemia in a Translational Swine Model

BACKGROUND

Cellular therapies have been investigated to improve blood flow and prevent amputation in peripheral artery disease with limited efficacy in clinical trials. Alginate-encapsulated mesenchymal stromal cells (eMSCs) demonstrated improved retention and survival and promoted vascular generation in murine hind limb ischemia through their secretome, but large animal evaluation is necessary for human applicability. We sought to determine the efficacy of eMSCs for peripheral artery disease-induced limb ischemia through assessment in our durable swine hind limb ischemia model.

METHODS AND RESULTS

Autologous bone marrow eMSCs or empty alginate capsules were intramuscularly injected 2 weeks post-hind limb ischemia establishment (N=4/group). Improvements were quantified for 4 weeks through walkway gait analysis, contrast angiography, blood pressures, fluorescent microsphere perfusion, and muscle morphology and histology. Capsules remained intact with mesenchymal stromal cells retained for 4 weeks. Adenosine-induced perfusion deficits and muscle atrophy in ischemic limbs were significantly improved by eMSCs versus empty capsules (mean±SD, 1.07±0.19 versus 0.41±0.16, P=0.002 for perfusion ratios and 2.79±0.12 versus 1.90±0.62 g/kg, P=0.029 for ischemic muscle mass). Force- and temporal-associated walkway parameters normalized (ratio, 0.63±0.35 at week 3 versus 1.02±0.19 preligation; P=0.17), and compensatory footfall patterning was diminished in eMSC-administered swine (12.58±8.46% versus 34.85±15.26%; P=0.043). Delivery of eMSCs was associated with trending benefits in collateralization, local neovascularization, and muscle fibrosis. Hypoxia-cultured porcine mesenchymal stromal cells secreted vascular endothelial growth factor and tissue inhibitor of metalloproteinase 2.

CONCLUSIONS

This study demonstrates the promise of the mesenchymal stromal cell secretome at improving peripheral artery disease outcomes and the potential for this novel swine model to serve as a component of the preclinical pipeline for advanced therapies.

The Inflammatory Pattern of Chronic Limb-Threatening Ischemia in Muscles: The TNF-α Hypothesis

Background: Vascular inflammation plays a crucial role in peripheral arterial disease (PAD), although the role of the mediators involved has not yet been properly defined. The aim of this work is to investigate gene expression and plasma biomarkers in chronic limb-threating ischemia (CLTI). Methods: Using patients from the GHAS trial, both blood and ischemic muscle samples were obtained to analyze plasma markers and mRNA expression, respectively. Statistical analysis was performed by using univariate (Spearman, t-Student, and X²) and multivariate (multiple logistic regression) tests. Results: A total of 35 patients were available at baseline (29 for mRNA expression). Baseline characteristics (mean): Age: 71.4 ± 12.4 years (79.4% male); TNF-α: 10.7 ± 4.9 pg/mL; hsCRP:1.6 ± 2.2 mg/dL; and neutrophil-to-lymphocyte ratio (NLR): 3.5 ± 2.8. Plasma TNF-α was found elevated (≥8.1) in 68.6% of patients, while high hsCRP (≥0.5) was found in 60.5%. Diabetic patients with a high level of inflammation showed significantly higher levels of NOX4 expression at baseline (p = 0.0346). Plasma TNF-α had a negative correlation with NOS3 (eNOS) expression (−0.5, p = 0.015) and plasma hsCRP with VEGFA (−0.63, p = 0.005). The expression of NOX4 was parallel to that of plasma TNF-α (0.305, p = 0.037), especially in DM. Cumulative mortality at 12 months was related to NLR ≥ 3 (p = 0.019) and TNF-α ≥ 8.1 (p = 0.048). The best cutoff point for NLR to predict mortality was 3.4. Conclusions: NOX4 and TNF-α are crucial for the development and complications of lower limb ischemia, especially in DM. hsCRP could have a negative influence on angiogenesis too. NLR and TNF-α represent suitable markers of mortality in CLTI. These results are novel because they connect muscle gene expression and plasma information in patients with advanced PAD, deepening the search for new and accurate targets for this condition.