Metabolic Syndrome in South Korean Patients with Chronic Obstructive Pulmonary Disease: A Focus on Gender Differences

The Relationship between Serum Uric Acid Levels and Early Mortality in Chronic Obstructive Pulmonary Disease Cases during Exacerbation

AIM

In this study, it was aimed to compare the levels of serum uric acid and uric acid/creatinine ratios in patients with COPD during an attack or in stable COPD, and to show whether serum uric acid and uric acid/creatinine ratios are associated with early mortality in COPD patients during an acute attack.

MATERIALS AND METHODS

In this study, COPD acute attack (n=155) and stable COPD (n=30) patients were evaluated. The data of these patients were obtained from patient files and computer records. COPD diagnosis and severity assessment were made according to the GOLD 2006 guideline. Participants' age, gender, body mass index, pulmonary function test, arterial blood gas, uric acid, creatinine values and comorbidity information were recorded in the previously prepared Case Data Form. In 2012, when we conducted this study, gold 2006 was taken as the guideline for spirometry measurement, but spirometric measurements determined with reference values determined according to age, height and gender, and FEV1/FVC measurement <70% as diagnostic criteria in acute attack after bronchodilator were the guidelines used later, gold 2017. It is also compatible with gold2020 and gold2021 spirometry criteria.

RESULTS

It was determined that the uric acid (p<0.001) and uric acid/creatinine (p<0.001) levels of the patients in the acute attack group were significantly higher than the levels of the patients in the stable group. The attack group was divided into two subgroups according to certain cut-off points for uric acid (>6 mg/dl for women and >7 mg/dl for men) and uric acid/creatinine ratio (median value 7.10). Since the upper limit of the uric acid value measured in the blood is 6 mg/dl in women and 7-8 mg/dl in men, the cut-off points for uric acid (>6 mg/dl for women and >7 mg/dl for men) were determined in our study. According to this categorization, it was determined that there was no statistically significant relationship between uric acid level (odds ratio 2.985 [95% confidence interval 0.61814,151]) and early mortality risk.

CONCLUSION

The results of this study showed that the uric acid and uric acid/creatinine levels in the attack group were higher than the levels in the stable group, but these parameters were not associated with early mortality.

Dynamic Metabolic Risk Profiling of World Trade Center Lung Disease: A Longitudinal Cohort Study

Rationale: Metabolic syndrome (MetSyn) increases the risk of World Trade Center (WTC) lung injury (LI). However, the temporal relationship of MetSyn, exposure intensity, and lung dysfunction is not well understood. Objective: To model the association of longitudinal MetSyn characteristics with WTC lung disease to define modifiable risk. Methods: Firefighters, for whom consent was obtained (N = 5,738), were active duty on September 11, 2001 (9/11). WTC-LI (n = 1,475; FEV₁% predicted <lower limit of normal [LLN]) and non-WTC-LI (n = 4,263; FEV₁% predicted ⩾LLN at all exams) was the primary outcome, and FVC% predicted <LLN and FEV₁/FVC <0.70 were secondary outcomes. We assessed 1) the effect of concurrent MetSyn on longitudinal lung function by linear mixed models, 2) the temporal effect of MetSyn and exposure by Weibull proportional hazards, 3) the effects of MetSyn's rate of change by two-stage models, and 4) the nonlinear joint effect of longitudinal MetSyn components by a partially linear single-index model (PLSI). Measurements and Main Results: WTC-LI cases were more often ever-smokers, arrived in the morning (9/11), and had MetSyn. Body mass index ⩾30 kg/m² and high-density lipoprotein <40 mg/dl were most contributory to concurrent loss of FEV₁% predicted and FVC% predicted while conserving FEV₁/FVC. Body mass index ⩾30 kg/m² and dyslipidemia significantly predicted WTC-LI, FVC% predicted <LLN in a Weibull proportional hazards model. Dynamic risk assessment of WTC-LI on the basis of MetSyn and exposure showed how reduction of MetSyn factors further reduces WTC-LI likelihood in susceptible populations. PLSI demonstrates that MetSyn has a nonlinear relationship with WTC lung disease, and increases in cumulative MetSyn risk factors exponentially increase WTC-LI risk. An interactive metabolic-risk modeling application was developed to simplify PLSI interpretation. Conclusions: MetSyn and WTC exposure contribute to the development of lung disease. Dynamic risk assessment may be used to encourage treatment of MetSyn in susceptible populations. Future studies will focus on dietary intervention as a disease modifier.

Genetic correlation and causal relationships between cardio-metabolic traits and lung function impairment

BACKGROUND

Associations of low lung function with features of poor cardio-metabolic health have been reported. It is, however, unclear whether these co-morbidities reflect causal associations, shared genetic heritability or are confounded by environmental factors.

METHODS

We performed three analyses: (1) cardio-metabolic health to lung function association tests in Northern Finland Birth cohort 1966, (2) cross-trait linkage disequilibrium score regression (LDSC) to compare genetic backgrounds and (3) Mendelian randomisation (MR) analysis to assess the causal effect of cardio-metabolic traits and disease on lung function, and vice versa (bidirectional MR). Genetic associations were obtained from the UK Biobank data or published large-scale genome-wide association studies (N > 82,000).

RESULTS

We observed a negative genetic correlation between lung function and cardio-metabolic traits and diseases. In Mendelian Randomisation analysis (MR), we found associations between type 2 diabetes (T2D) instruments and forced vital capacity (FVC) as well as FEV1/FVC. Body mass index (BMI) instruments were associated to all lung function traits and C-reactive protein (CRP) instruments to FVC. These genetic associations provide evidence for a causal effect of cardio-metabolic traits on lung function. Multivariable MR suggested independence of these causal effects from other tested cardio-metabolic traits and diseases. Analysis of lung function specific SNPs revealed a potential causal effect of FEV1/FVC on blood pressure.

CONCLUSIONS

The present study overcomes many limitations of observational studies by using Mendelian Randomisation. We provide evidence for an independent causal effect of T2D, CRP and BMI on lung function with some of the T2D effect on lung function being attributed to inflammatory mechanisms. Furthermore, this analysis suggests a potential causal effect of FEV1/FVC on blood pressure. Our detailed analysis of the interplay between cardio-metabolic traits and impaired lung function provides the opportunity to improve the quality of existing intervention strategies.

The Effect of Metabolic Syndrome Status on Lung Function and Patient-reported Outcomes in Patients with COPD Receiving Nebulized Glycopyrrolate

Background

Concurrent chronic obstructive pulmonary disease (COPD) and metabolic syndrome (MetS) represent an important clinical phenotype with overlapping symptomology. The effect of MetS in COPD patients was assessed following treatment with nebulized glycopyrrolate (GLY; administered via eFlow® Closed System Nebulizer).

Methods

Posthoc analyses were performed on pooled lung function, patient-reported outcome (PRO) and safety data by MetS status from patients treated with placebo, GLY 25 and 50 mcg twice daily in two 12-week studies (GOLDEN 3 and 4; N=1293). Patients with MetS were characterized as having ≥ 3 of hypertension, hyperlipidemia, diabetes, body mass index (BMI) > 30 kg/m² risk factors. The results are presented for the Food and Drug Administration-approved GLY 25 mcg dose.

Results

A total of25% of patients met MetS criteria.At baseline, the MetS subgroup had higher BMIs, more ex-smokers, greater incidences of cardiovascular risk factors, and MetS-specific risk factors were 2-14 times higher than non-MetS. At 12 weeks, GLY produced significant, clinically important improvements (MetS: 0.121 L; non-MetS: 0.083 L) in trough forced expiratory volume in 1 second. In the non-MetS group, significant improvements occurred in the St George's Respiratory Questionnaire (MetS: -2.28, p=0.157; non-MetS: -3.71) and Evaluating Respiratory Symptoms in COPD tool (MetS: 0.42, p=0.574; non-MetS: -1.61) total scores. Incidence of adverse events was similar with GLY versus placebo regardless of MetS status.

Conclusion

GLY was well-tolerated and significantly improved lung function regardless of MetS status, while significant PRO improvements occurred in non-MetS patients. These results highlight the importance of comorbidities on bronchodilator responses and patient symptoms in COPD patients.

Gender Differences in the Pharmacological Actions of Pegylated Glucagon-Like Peptide-1 on Endothelial Progenitor Cells and Angiogenic Precursor Cells in a Combination of Metabolic Disorders and Lung Emphysema

In clinical practice, the metabolic syndrome (MetS) is often associated with chronic obstructive pulmonary disease (COPD). Although gender differences in MetS are well documented, little is known about sex-specific differences in the pathogenesis of COPD, especially when combined with MetS. Consequently, it is not clear whether the same treatment regime has comparable efficacy in men and women diagnosed with MetS and COPD. In the present study, using sodium glutamate, lipopolysaccharide, and cigarette smoke extract, we simulated lipid metabolism disorders, obesity, hyperglycemia, and pulmonary emphysema (comorbidity) in male and female C57BL/6 mice. We assessed the gender-specific impact of lipid metabolism disorders and pulmonary emphysema on angiogenic precursor cells (endothelial progenitor cells (EPC), pericytes, vascular smooth muscle cells, cells of the lumen of the nascent vessel), as well as the biological effects of pegylated glucagon-like peptide 1 (pegGLP-1) in this experimental paradigm. Simulation of MetS/COPD comorbidity caused an accumulation of EPC (CD45⁻CD31⁺CD34⁺), pericytes, and vascular smooth muscle cells in the lungs of female mice. In contrast, the number of cells involved in the angiogenesis decreased in the lungs of male animals. PegGLP-1 had a positive effect on lipids and area under the curve (AUC), obesity, and prevented the development of pulmonary emphysema. The severity of these effects was stronger in males than in females. Furthermore, PegGLP-1 stimulated regeneration of pulmonary endothelium. At the same time, PegGLP-1 administration caused a mobilization of EPC (CD45⁻CD31⁺CD34⁺) into the bloodstream in females and migration of precursors of angiogenesis and vascular smooth muscle cells to the lungs in male animals. Gender differences in stimulatory action of pegGLP-1 on CD31⁺ endothelial lung cells in vitro were not observed. Based on these findings, we postulated that the cellular mechanism of in vivo regeneration of lung epithelium was at least partly gender-specific. Thus, we concluded that a pegGLP-1-based treatment regime for metabolic disorder and COPD should be further developed primarily for male patients.

Dihydromyricetin Attenuates Metabolic Syndrome And Improves Insulin Sensitivity By Upregulating Insulin Receptor Substrate-1 (Y612) Tyrosine Phosphorylation In db/db Mice

PURPOSE

Dihydromyricetin (DHM), the main bioactive flavonoid in vine tea, exerts multiple health beneficial effects. This work aimed to identify whether a naturally derived flavonoid product, DHM, can significantly attenuate metabolic syndrome and improve insulin sensitivity.

METHODS

10-week-old db/db mice were randomly assigned to receive the antidiabetic agent metformin (Met, 50 mg/kg BW), DHM (1.0 g and 0.5 g/kg BW) or placebo and were simultaneously fed a high-fat diet for 8 weeks. The general status of the animals was observed and recorded daily, body weight and blood glucose levels were measured weekly, during the experimental period. On day 55, the oral glucose tolerance test (OGTT) was performed. After OGTT, all animals were anesthetized and sacrificed by cervical decapitation. Blood samples were collected in tubes to detect plasma insulin and the biochemical parameters of lipid metabolism. Pancreas histological changes and islet fibrosis were demonstrated by H&E staining and Masson staining, respectively. Moreover, the expression of insulin receptor substrate-1 and phosphorylated insulin receptor substrate-1 in the insulin signaling pathway was detected by Western blot assay.

RESULTS

The oral administration of DHM (1.0 g and 0.5 g/kg BW) reduced the fasting blood glucose, serum insulin, and glycated hemoglobin levels and the insulin resistance (HOMA-IR) index. Furthermore, DHM intervention decreased body weight and the serum lipid profile. In addition, DHM treatment also markedly decreased the relative abdominal fat weight. Western blot analysis indicated that DHM upregulated the IRS-1 (Y612) tyrosine phosphorylation, improving insulin resistance. Treatment with dihydromyricetin attenuated the progression of insulin resistance and pancreatic fibrosis in fatty db/db mice.

CONCLUSION

In summary, we determined the antimetabolic syndrome effect of DHM in db/db obese mice. DHM upregulates the IRS-1 (Y612) tyrosine phosphorylation, improving insulin resistance. Therefore, DHM is a promising therapeutic candidate for the control of metabolic syndrome.