Leukocyte Function in COPD: Clinical Relevance and Potential for Drug Therapy

Anti-inflammatory effect of Anadenanthera colubrina var. cebil (Griseb.) Altschul in experimental elastase-induced pulmonary emphysema in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Medicinal plants have shown promise in the search for new treatments of pulmonary emphysema. Anadenanthera colubrina, a species native to the Caatinga biome in northeastern Brazil, is widely recognized and traditionally employed in the treatment of pulmonary diseases. Many studies corroborate popular knowledge about the medicinal applications of A. colubrina, which has demonstrated a remarkable variety of pharmacological properties, however, its anti-inflammatory and antioxidant properties are highlighted.

AIM OF THE STUDY

The objective of this study was to investigate the anti-inflammatory potential of the crude hydroethanolic extract of A. colubrina var. cebil (Griseb.) Altschul on pulmonary emphysema in rats as well as to determine its potential genotoxic and cytotoxic effects using the micronucleus assay.

MATERIALS AND METHODS

The stem bark of the plant was collected in Pimenteiras-PI and sample was extracted by maceration using 70% ethanol. A portion of the extract underwent phytochemical analyses using TLC and HPLC. In this study, 8-week-old, male Wistar rats weighing approximately ±200 g was utilized following approval by local ethics committee for animal experimentation (No. 718/2022). Pulmonary emphysema was induced through orotracheal instillation of elastase, and treatment with A. colubrina extract or dexamethasone (positive control) concomitantly during induction. Twenty-eight days after the initiation of the protocol, plasma was used for cytokine measurement. Bronchoalveolar lavage (BAL) was used for leukocyte count. After euthanasia, lung samples were processed for histological analysis and quantification of oxidative stress markers. The micronucleus test was performed by evaluating the number of polychromatic erythrocytes (PCE) with micronuclei (MNPCE) to verify potential genotoxic effects of A. colubrina. A differential count of PCE and normochromatic erythrocytes (NCE) was performed to verify the potential cytotoxicity of the extract. Parametric data were subjected to normality analysis and subsequently to analysis of variance and Tukey or Dunnett post-test, non-parametric data were treated using the Kruskal-Wallis test with Dunn's post-test for unpaired samples. P value < 0.05 were considered significant.

RESULTS

The A. colubrina extract did not show a significant increase in the number of MNPCE (p > 0.05), demonstrating low genotoxicity. No changes were observed in the PCE/NCE ratio of treated animals, compared with the vehicle, suggesting low cytotoxic potential of the extract. A significant reduction (p < 0.05) in neutrophilic inflammation was observed in the lungs of rats treated with the extract, evidenced by presence of these cells in both the tissue and BAL. The extract also demonstrated pulmonary antioxidant activity, with a significant decrease (p < 0.05) in myeloperoxidase, malondialdehyde, and nitrite levels. TNFα, IL-1β, and IL-6 levels, as well as alveolar damage, were significantly reduced in animals treated with A. colubrina extract. Phytochemical analyses identified the presence of phenolic compounds and hydrolysable tannins in the A. colubrina extract.

CONCLUSIONS

The findings of this study highlights the safety of the hydroethanolic extract of Anadenanthera colubrina, and demonstrates its potential as a therapeutic approach in the treatment of emphysema. The observed properties of this medicinal plant provide an optimistic outlook in the development of therapies for the treatment of pulmonary emphysema.

Metabolic pathways in immune senescence and inflammaging: Novel therapeutic strategy for chronic inflammatory lung diseases. An EAACI position paper from the Task Force for Immunopharmacology

The accumulation of senescent cells drives inflammaging and increases morbidity of chronic inflammatory lung diseases. Immune responses are built upon dynamic changes in cell metabolism that supply energy and substrates for cell proliferation, differentiation, and activation. Metabolic changes imposed by environmental stress and inflammation on immune cells and tissue microenvironment are thus chiefly involved in the pathophysiology of allergic and other immune-driven diseases. Altered cell metabolism is also a hallmark of cell senescence, a condition characterized by loss of proliferative activity in cells that remain metabolically active. Accelerated senescence can be triggered by acute or chronic stress and inflammatory responses. In contrast, replicative senescence occurs as part of the physiological aging process and has protective roles in cancer surveillance and wound healing. Importantly, cell senescence can also change or hamper response to diverse therapeutic treatments. Understanding the metabolic pathways of senescence in immune and structural cells is therefore critical to detect, prevent, or revert detrimental aspects of senescence-related immunopathology, by developing specific diagnostics and targeted therapies. In this paper, we review the main changes and metabolic alterations occurring in senescent immune cells (macrophages, B cells, T cells). Subsequently, we present the metabolic footprints described in translational studies in patients with chronic asthma and chronic obstructive pulmonary disease (COPD), and review the ongoing preclinical studies and clinical trials of therapeutic approaches aiming at targeting metabolic pathways to antagonize pathological senescence. Because this is a recently emerging field in allergy and clinical immunology, a better understanding of the metabolic profile of the complex landscape of cell senescence is needed. The progress achieved so far is already providing opportunities for new therapies, as well as for strategies aimed at disease prevention and supporting healthy aging.

Meta-analysis of peripheral blood eosinophils in clinical testing of chronic obstructive pulmonary disease patients

Introduction

Meta-analysis was used to investigate the relationship between peripheral blood eosinophil (EOS) levels, clinical characteristics, and prognosis in chronic obstructive pulmonary disease (COPD)patients in previous literature.

Aim

To analyse the correlation between peripheral blood EOS levels and clinical characteristics and prognosis of patients with COPD using meta-analysis.

Material and methods

In databases such as PubMed, Embase, Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wan Fang Data, literature related to the clinical characteristics or prognosis of COPD patients with high-level EOS published before July 2023 was searched for meta-analysis.

Results

Through computer search and screening, 29 articles were ultimately included. The meta-analysis results showed that compared to conventional EOS levels, COPD patients with high EOS levels had a lower proportion of GOLD III-IV grade patients (OR = 00.78, 95% CI (0.68, 0.88), p < 0.001), lower CAT scores (OR = -1.01, 95% CI (-1.75, -0.28), p = 0.007), shorter hospital stay (OR = -1.33, 95% CI (-1.52, -1.14), p < 0.001), and lower mortality rate (OR = 0.53, 95% CI (0.42, 0.66), p < 0.001). The readmission rate was low (OR = 0.40, 95% CI (0.33, 0.48), p < 0.001), and there was no statistically significant difference in FEV1%pred (OR = -0.55, 95% CI (-1.33, 0.23), p = 0.17), higher FEV1/FVC values (OR = -0.45, 95% CI (-1.08, 0.18), p = 0.160), and mechanical ventilation usage rate (OR = 0.89, 95% CI (0.65, 1.21), p = 0.450) among COPD patients with different EOS levels.

Conclusions

The levels of peripheral blood EOS in COPD patients are related to lung function, respiratory symptoms, etc.; Moreover, COPD patients with high-level EOS have shorter hospital stays, lower mortality and readmission rates. Therefore, ESO can be used as an auxiliary indicator for clinical symptom diagnosis of COPD patients and as an auxiliary indicator for predicting prognosis.

Serum YKL-40 Levels, Leukocyte Profiles, and Acute Exacerbations of Advanced COPD

Little information exists on YKL-40-a key protein in tissue remodeling-and complete blood count (CBC) parameters during acute exacerbations of advanced chronic obstructive pulmonary disease (COPD). This pilot exploratory study (August 2020-January 2021) investigated the connection between serum YKL-40 levels and CBC profile in sex- and age-matched individuals with severe COPD (GOLD stage III, n = 23, median age = 66 years, 65.21% males) and very severe COPD (GOLD stage IV, n = 24, median age = 66.5 years, 74.81% males). The measured parameters were serum YKL-40, absolute leukocyte count (ALLC), absolute neutrophil count (ANC), neutrophil percentage, absolute lymphocyte count (ALC), lymphocyte percentage, neutrophil-to-lymphocyte ratio (NLR), absolute eosinophil count (AEC), eosinophil percentage, absolute monocyte count (AMC), monocyte percentage, absolute basophil count (ABC), basophil percentage, hemoglobin levels, and hematocrit concentrations. No significant inter-group differences were observed. However, high YKL-40 subjects (n = 23)-as stratified via median YKL-40 (3934.5 pg/mL)-showed significantly increased neutrophil percentage and NLR but significantly lower lymphocyte-, eosinophil-, and basophil-related parameters compared to low YKL-40 patients (n = 24). These results reveal multidimensional, YKL-40-associated changes in leukocyte profile of patients with advanced COPD during acute exacerbations, with potential implications for personalized treatment.

Prognostic value of lymphocyte count for in-hospital mortality in patients with severe AECOPD

Background

Patients with severe acute exacerbations of chronic obstructive pulmonary disease often have a poor prognosis. Biomarkers can help clinicians personalize the assessment of different patients and mitigate mortality. The present study sought to determine if the lymphocyte count could act as a risk factor for mortality in individuals with severe AECOPD.

Methods

A retrospective study was carried out with 458 cases who had severe AECOPD. For analysis, patients were divided into two groups on the basis of lymphocyte count: < 0.8 × 10⁹/L and ≥ 0.8 × 10⁹/L.

Results

Patients who fulfilled the criteria for inclusion were enrolled, namely 458 with a mean age of 78.2 ± 8.2 years. Of these patients, 175 had a low lymphocyte count. Compared to patients with normal lymphocyte counts, those with low counts were older (79.2 ± 7.4 vs. 77.5 ± 8.6 years, p = 0.036), had lower activities of daily living scores on admission (35.9 ± 27.6 vs. 47.5 ± 17.1, p < 0.001), and had a greater need for home oxygen therapy (84.6 vs. 72.1%, p = 0.002). Patients with low lymphocytes had higher mortality rates during hospitalization (17.1 vs. 7.1%, p = 0.001), longer hospital stay (median [IQR] 16 days [12–26] vs. 14 days [10–20], p = 0.002) and longer time on mechanical ventilation (median [IQR] 11.6 days [5.8–18.7] vs. 10.9 days [3.8–11.6], p < 0.001). The logistic regression analysis showed lymphocyte count < 0.8 × 10⁹/L was an independent risk factor associated with in-hospital mortality (OR 2.74, 95%CI 1.33–5.66, p = 0.006).

Conclusion

Lymphocyte count could act as a predictor of mortality in patients with severe AECOPD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-02137-1.

Effect of erythromycin on the ultrastructure of human macrophages exposed to cigarette smoke extract in vitro

Macrophages serve an active role in the pathophysiology of chronic obstructive pulmonary disease (COPD). Erythromycin (EM) has been verified as an effective treatment for COPD. However, there are few studies on the effect of EM on the ultrastructure of macrophages exposed to cigarette smoke extract (CSE). In the present study, human macrophages were randomly divided into three groups: The control, CSE and the CSE+EM group, using electron microscopy, the effect of EM was evaluated by comparing the ultrastructural changes between these groups. The macrophages were additionally divided into a further four groups: The control, CSE, CSE+EM 24 h and CSE+EM 48 h groups. The generation of reactive oxygen species (ROS) in each group was evaluated by detecting fluorescence intensity. It was observed that the cellular ultrastructure of the CSE group exhibited abnormal changes, though this effect was reversed back to the level of the control in the CSE+EM group. Compared with the control group, the ROS expression level was significantly increased in the CSE group (P < .05); however, compared with the CSE group, the ROS concentration was decreased in the CSE+EM 24 h (P < .05) and CSE+EM 48 h groups (P < .05), though this was more apparent in the EM 48 h group. It was concluded that EM protects human macrophages against CSE. Moreover, it was hypothesized that EM may reduce the symptoms of patients with COPD by protecting the macrophage ultrastructure from the effects of CSE, resulting in the decreased generation of ROS, inhibiting autophagy and reducing endoplasmic reticulum stress.

An Overview of the Safety and Efficacy of Monoclonal Antibodies for the Chronic Obstructive Pulmonary Disease

Several mAbs have been tested or are currently under clinical evaluation for the treatment of COPD. They can be subdivided into those that aim to block specific pro-inflammatory and pro-neutrophilic cytokines and chemokines, such as TNF-α, IL-1β, CXCL8 and IL-1β, and those that act on T2-mediated inflammation, respectively, by blocking IL-5 and/or its receptor, preventing IL-4 and IL-13 signaling, affecting IL-33 pathway and blocking TSLP. None of these approaches has proved to be effective, probably because in COPD there is no dominant cytokine or chemokine and, therefore, a single mAb cannot be effective on all pathways. With a more in-depth understanding of the numerous pheno/endotypic pathways that play a role in COPD, it may eventually be possible to identify those specific patients in whom some of these cytokines or chemokines might predominate. In this case, it will be possible to implement a personalized treatment, but the use of each mAb will only be reserved for a very limited number of subjects.