Chronic obstructive pulmonary disease: an update of treatment related to frequently associated comorbidities

Promising role of peroxisome proliferator-activated receptors in respiratory disorders, a review

Several studies indicate various pharmacological and therapeutic effects of peroxisome proliferator-activated receptors (PPARs) in different disorders. The current review describes the influences of PPARs on respiratory, allergic, and immunologic diseases. Various databases, including PubMed, Science Direct, and Scopus, were searched regarding the effect of PPARs on respiratory and allergic disorders from 1990 to 2024. The effects of PPARs stimulation on experimental animal models of respiratory diseases such as asthma, chronic obstructive pulmonary diseases (COPD), pulmonary fibrosis (PF), and lung infections were shown. Therapeutic potential mediated through PPARs has also been demonstrated in lung cancer, lung infections, and allergic and immunologic disorders. However, few clinical studies showed PPARs mediated therapeutic effects on asthma and COPD. The PPARs-mediated effects on various respiratory disorders were shown through antioxidant, immunomodulatory, anti-inflammatory, and other mechanisms. Therefore, this review indicated possible remedy effects mediated by these receptors in treating respiratory, allergic, and immunologic diseases. Moreover, this mechanistic review paves the way for researchers to consider further experimental and clinical studies.

Pulmonary Rehabilitation in Management of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is an obstructive and progressive airway disorder that is linked with a significant loss in daily physical activity as well as psychological issues that contribute to the patient's impairment and poor health-related quality of life. Over the last two decades, however, the research and application of nonpharmacologic therapies such as lung rehabilitation have been expedited with increasing evidence of systemic events in COPD patient groups and their nugatory impact on their functioning pulmonary rehabilitation (PR). It is a key part of integrated treatment for COPD and other chronic breathing disorders and is helpful in supporting the recovery of patients following COPD hospitalization. In this paper, we summarize current evidence regarding the effectiveness of PR in the management of chronic COPD. A systematic review was carried out during June 2021, searching databases PubMed, Google Scholar, and EBSCO. The authors extracted qualitative data, and then the author's names, year, study type, methodology, and the result were reported. The search of the aforementioned databases returned a total of 127 studies that were included for title, abstract, and full-text screening, and nine studies were enrolled for final data extraction. PR alleviates tiredness and dyspnea, improves emotional function, and increases the ability to do daily activities. These benefits are relatively extensive and substantial clinically. Rehabilitation acts as an important component of COPD management and helps to improve the quality of life and training linked to health.

In vitro study of the role of FOXO transcription factors in regulating cigarette smoke extract-induced autophagy

Cigarette smoking is the chief etiological factor for chronic obstructive pulmonary disease (COPD). Oxidative stress induced by cigarette smoke (CS) causes protein degradation, DNA damage, and cell death, thereby resulting in acute lung injury (ALI). In this regard, autophagy plays a critical role in regulating inflammatory responses by maintaining protein and organelle homeostasis and cellular viability. Expression of autophagy-related proteins (ARPs) is regulated by the fork head box class O (FOXO) transcription factors. In the current study, we examined the role of FOXO family proteins-FOXO1 and FOXO3a-in regulating CS extract (CSE)-induced autophagy. Using human lung adenocarcinoma cells with type II alveolar epithelial characteristics (A549), we observed CSE-mediated downregulation of FOXO3a. In contrast, there was a pronounced increase in the expression of FOXO1 at both the transcriptional and translational levels in the CSE-challenged cells compared with controls. Interestingly, knockdown of FOXO3a heightened the CSE-mediated increase in expression of cytokines/chemokines (IL-6, IL-8, and MCP-1), ARPs, and the FOXO1 transcription factor. Moreover, FOXO1 knockdown rescued CSE-mediated upregulation of ARPs in A549 cells. In addition, using the ROS inhibitor N-acetyl-L-cysteine (NAC), we observed abrogated mRNA expression of several ARPs and production of inflammatory cytokines/chemokines (IL-6, IL-8, MCP-1, and CCL-5) in the CSE-challenged cells suggesting an important role of ROS in regulating CSE-induced autophagy. Chromatin immunoprecipitation of FOXO1 and FOXO3a demonstrated increased binding of the former to promoter regions of autophagy genes- BECLIN1, ATG5, ATG12, ATG16, and LC3 in CSE challenged cells. These findings suggest the role of FOXO1 in regulating the expression of these genes during CSE exposure. Overall, our findings provide evidence for FOXO3a-dependent FOXO1-mediated regulation of autophagy in the CSE-challenged cells. Graphical abstract.

Fortified whey beverage for improving muscle mass in chronic obstructive pulmonary disease: a single-blind, randomized clinical trial

Background

The development of effective nutritional supports for patients with chronic obstructive pulmonary diseases (COPD) is still challenging. This study was conducted to investigate the efficacy of daily consumption of fortified whey on inflammation, muscle mass, functionality, and quality of life in patients with moderate-to-severe COPD.

Methods

A single-blind, randomized trial study was performed on patients with COPD (n = 46). Participants in the intervention group (n = 23) daily received 250 ml of whey beverage fortified with magnesium and vitamin C for 8 weeks. Any changes in inflammatory cytokines (including interleukin- 6 (IL-6) and tumor necrosis factor (TNFα)) were the primary outcomes and the secondary outcomes were fat-free mass, handgrip strength, malnutrition, glutathione and malondialdehyde serum concentrations, and health-related quality of life (HRQoL). Body composition and muscle strength were measured by Bioelectrical Impedance Analysis (BIA) and hydraulic hand dynamometer, respectively. Fat-free mass index (FFMI) was also calculated.

Results

At the end of the study, 44 patients were analyzed. There were significant decreases in IL-6 concentrations in the intervention group compared to the control group. Also, FFMI, body protein, and handgrip strength increased significantly in the intervention group with significant changes between two groups. Moreover, improvement in health-related quality of life was observed in the intervention group compared to the control group. There were no significant changes in other study variables.

Conclusions

This novel nutritional intervention decreased inflammatory cytokines levels, improved indices of skeletal muscle mass and muscle strength, and ultimately, increased HRQoL in patients with moderate-to-severe COPD. Thus, it is suggested to do further studies to assess the effects of nutrition intervention on COPD progression.

Trial registration

IR.SUMS.REC.1396.85 (https://www.irct.ir/).

Association between blood pressure, inflammation and spirometry parameters in chronic obstructive pulmonary disease

BACKGROUND/AIMS

Many systems including the cardiovascular system (ischemic heart diseases, heart failure, and hypertension) may act as comorbidities that can be seen during the course of chronic obstructive pulmonary disease (COPD). Comorbidities affect the severity and prognosis of COPD negatively. Nearly 25% of patients with COPD die due to cardiovascular diseases. In this study, we aimed to evaluate the relationship between the blood pressure, inflammation, hypoxia, hypercapnia, and the severity of airway obstruction.

METHODS

We included 75 COPD patients in the study with 45 control cases. We evaluated age, sex, body mass index, smoking history, C-reactive protein levels, 24-hour ambulatory blood pressure Holter monitoring, arterial blood gas, and respiratory function tests of the patient and the control groups.

RESULTS

In COPD patients, the night time systolic, diastolic blood pressures and pulse per minute and the mean blood pressures readings were significantly elevated compared to the control group (p < 0.05). In the correlation analysis, night time systolic pressure was associated with all the parameters except forced expiratory volume in 1 second (FEV1%). Diastolic blood pressure was associated with pH and HCO3 levels. The mean night time, day time pulse pressures and 24- hour pulse per minute values were also associated with all the parameters except FEV1%.

CONCLUSION

In this study we found that parameters of systolic and diastolic blood pressures and pulse pressures were significantly elevated in COPD patients compared to the control groups. Blood pressure was associated blood gas parameters and inflammation parameters in COPD patients. This, in turn, may cause understanding of the pathophysiology of COPD and its complications.

Relationship between pulmonary function and elevated glycated hemoglobin levels in health checkups: A cross-sectional observational study in Japanese participants

Background

Insulin resistance has been associated with cytokines, including interleukin-6 and tumor necrosis factor alpha soluble receptor, both of which are elevated in chronic obstructive pulmonary disease (COPD). Few studies have investigated the relationship between pulmonary function tests using spirometry (PFT) and fasting plasma glucose (FPG) or glycated hemoglobin (HbA_1c) levels in Japanese participants. The purpose of this study was to clarify the relationship between PFT in Japanese people who had health checkups and their FPG or HbA_1c levels. In the context of preventative medicine, we intend to connect early detection of COPD to an index of blood sugar.

Methods

From August 2013 through March 2014, 1019 participants underwent health checkups. PFT, FPG, and HbA_1c measurements were conducted. HbA_1c levels were measured according to National Glycohemoglobin Standardization Program guidelines.

Results

Participants with FPG ≥100 mg/dL and HbA_1c ≥5.6% showed a significantly lower forced expiratory volume in 1 s:forced vital capacity ratio (FEV₁/FVC) compared to participants with lower FPG and Hb1Ac levels. Prevalence of FEV₁/FVC values <70% in PFT differed significantly depending on sex, age, body mass index, FPG, HbA_1c, and smoking habits. Age (≥60 years), HbA_1c (≥5.6%), and current or former smoking were associated with FEV₁/FVC values <70%.

Conclusion

In Japan, HbA_1c levels were higher in participants with FEV₁/FVC values <70% in PFT than in those with FEV₁/FVC ≥70%. In preventive medicine, PFT by spirometry should be performed in elderly participants with elevated HbA_1c levels who are current or former smokers.

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Participants with FEV₁/FVC values <70% had significantly elevated HbA_1c levels.

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Age, HbA1c, and current or former smoking were associated with FEV₁/FVC values <70%.

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Elderly ever smokers with elevated HbA_1c should undergo screened for COPD.

Association between all-cause and cause-specific mortality and the GOLD stages 1-4: A 30-year follow-up among Finnish adults

BACKGROUND

Mortality correlates with the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria of airway obstruction. Yet, little data exist concerning the long-term survival of patients presenting with different levels of obstruction.

METHODS

We studied the association between all-cause and cause-specific mortality and GOLD stages 1-4 in a 30-year follow-up among 6636 Finnish men and women aged 30 or older participating in the Mini-Finland Health Study between 1978 and 1980.

RESULTS

After adjusting for age, sex, and smoking history, the GOLD stage of the subject showed a strong direct relationship with all-cause mortality, mortality from cardiovascular and respiratory diseases, and cancer. The adjusted hazard ratios of death were 1.27 (95% confidence interval (CI) 1.06-1.51), 1.40 (1.21-1.63), 1.55 (1.21-1.97) and 2.85 (1.65-4.94) for GOLD stages 1-4, respectively, with FEV1/FVC ≥70% as the reference. The association between GOLD stages 2-4 and mortality was strongest among subjects under 50 years of age at the baseline measurement. Cardiovascular mortality increased consistently for all GOLD stages.

CONCLUSIONS

Airway obstruction indicates an increased risk for all-cause mortality according to the severity of the GOLD stage. We found that even stage 1 carries a risk for cardiovascular death independently of smoking history and other known risk factors.

Improving communication between the physician and the COPD patient: an evaluation of the utility of the COPD Assessment Test in primary care

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide. It is now considered a systemic inflammatory syndrome and is associated with important comorbidities. In addition to spirometry for evaluating the severity of airflow obstruction, an instrument is required for comprehensive assessment of the disease. The COPD Assessment Test (CAT) is a simple and valid tool for evaluating patient symptoms. The CAT can improve patient–physician communication during routine clinical visits and is useful for assessing functional status and response to treatment. The CAT has a strong correlation with other health status questionnaires, such as the St George’s Respiratory Questionnaire. The main advantages of the CAT are its thorough coverage of the important clinical aspects of disease burden and the shorter time involved in completing it. The aim of this paper is to review the role of the CAT, to compare it with other health-related quality of life questionnaires in the assessment and management of COPD patients, and to emphasize the importance of patient–physician communication in the management of patients with the disease.

Cigarette smoke activates the proto-oncogene c-src to promote airway inflammation and lung tissue destruction

The diagnosis of chronic obstructive pulmonary disease (COPD) confers a 2-fold increased lung cancer risk even after adjusting for cigarette smoking, suggesting that common pathways are operative in both diseases. Although the role of the tyrosine kinase c-Src is established in lung cancer, less is known about its impact in other lung diseases, such as COPD. This study examined whether c-Src activation by cigarette smoke contributes to the pathogenesis of COPD. Cigarette smoke increased c-Src activity in human small airway epithelial (SAE) cells from healthy donors and in the lungs of exposed mice. Similarly, higher c-Src activation was measured in SAE cells from patients with COPD compared with healthy control subjects. In SAE cells, c-Src silencing or chemical inhibition prevented epidermal growth factor (EGF) receptor signaling in response to cigarette smoke but not EGF stimulation. Further studies showed that cigarette smoke acted through protein kinase C α to trigger c-Src to phosphorylate EGF receptor and thereby to induce mitogen-activated protein kinase responses in these cells. To further investigate the role of c-Src, A/J mice were orally administered the specific Src inhibitor AZD-0530 while they were exposed to cigarette smoke for 2 months. AZD-0530 treatment blocked c-Src activation, decreased macrophage influx, and prevented airspace enlargement in the lungs of cigarette smoke-exposed mice. Moreover, inhibiting Src deterred the cigarette smoke-mediated induction of matrix metalloproteinase-9 and -12 in alveolar macrophages and lung expression of cathepsin K, IL-17, TNF-α, MCP-1, and KC, all key factors in the pathogenesis of COPD. These results indicate that activation of the proto-oncogene c-Src by cigarette smoke promotes processes linked to the development of COPD.

Brd4 is essential for IL-1β-induced inflammation in human airway epithelial cells

BACKGROUND

Chronic inflammation and oxidative stress are key features of chronic obstructive pulmonary disease (COPD). Oxidative stress enhances COPD inflammation under the control of the pro-inflammatory redox-sensitive transcription factor nuclear factor-kappaB (NF-κB). Histone acetylation plays a critical role in chronic inflammation and bromodomain and extra terminal (BET) proteins act as "readers" of acetylated histones. Therefore, we examined the role of BET proteins in particular Brd2 and Brd4 and their inhibitors (JQ1 and PFI-1) in oxidative stress- enhanced inflammation in human bronchial epithelial cells.

METHODS

Human primary epithelial (NHBE) cells and BEAS-2B cell lines were stimulated with IL-1β (inflammatory stimulus) in the presence or absence of H2O2 (oxidative stress) and the effect of pre-treatment with bromodomain inhibitors (JQ1 and PFI-1) was investigated. Pro-inflammatory mediators (CXCL8 and IL-6) were measured by ELISA and transcripts by RT-PCR. H3 and H4 acetylation and recruitment of p65 and Brd4 to the native IL-8 and IL-6 promoters was investigated using chromatin immunoprecipitation (ChIP). The impact of Brd2 and Brd4 siRNA knockdown on inflammatory mediators was also investigated.

RESULT

H2O2 enhanced IL1β-induced IL-6 and CXCL8 expression in NHBE and BEAS-2B cells whereas H2O2 alone did not have any affect. H3 acetylation at the IL-6 and IL-8 promoters was associated with recruitment of p65 and Brd4 proteins. Although p65 acetylation was increased this was not directly targeted by Brd4. The BET inhibitors JQ1 and PFI-1 significantly reduced IL-6 and CXCL8 expression whereas no effect was seen with the inactive enantiomer JQ1(-). Brd4, but not Brd2, knockdown markedly reduced IL-6 and CXCL8 release. JQ1 also inhibited p65 and Brd4 recruitment to the IL-6 and IL-8 promoters.

CONCLUSION

Oxidative stress enhanced IL1β-induced IL-6 and CXCL8 expression was significantly reduced by Brd4 inhibition. Brd4 plays an important role in the regulation of inflammatory genes and provides a potential novel anti-inflammatory target.