Associations between serum mitokine levels and outcomes in stable COPD: an observational prospective study

Mitokines (Humanin (HN), GDF15 and FGF21) are produced as a result of mitochondrial dysfunction and may have major roles in chronic inflammation, malnutrition and exercise capacity in people with COPD. Except for GDF15, studies on this subject are lacking. A total of 165 patients with stable COPD and 49 smokers without COPD were enrolled. We assessed their serum mitokine levels and clinical characteristics at baseline. We recorded moderate and severe exacerbation for the next 12 months. Baseline serum HN (p = 0.037) and GDF-15 (p = 0.013) levels were higher in the COPD group. High HN levels were independently associated with a high risk of exacerbation (HRE) (OR 2.798, 95% CI 1.266-6.187, p = 0.011), malnutrition (OR 6.645, 95% CI 1.859-23.749, p = 0.004), and 6MWD (OR 0.995, 95% CI 0.991-0.999, p = 0.008), and future moderate (HR 1.826, 95% CI 1.181-2.822, p = 0.007) and severe exacerbations (HR 3.445, 95% CI 1.357-8.740, p = 0.009). High GDF15 levels were associated with HRE (OR 3.028, 95% CI 1.134-8.083, p = 0.027), 6MWD (OR 0.995, 95% CI 0.990-0.999, p = 0.017) and predicted desaturation in 6MWT (OR 3.999, 95% CI 1.487-10.757, p = 0.006). High FGF21 levels were associated with HRE (OR 2.144, 95% CI 1.000-4.600, p = 0.05), and predicted future severe exacerbation (HR 4.217, 95% CI 1.459-12.193, p = 0.008). The mitokine levels were higher in patients with COPD than smokers without COPD, and were associated with important clinical outcomes such as exercise capacity and COPD exacerbation. Among the mitokines, HN showed the strongest association with COPD and may serve as a future risk biomarker in this disease.Trial registation NCT04449419.Funding: This study was funded by Instituto de investigación sanitaria of Cantabria (IDIVAL): NextVAL grant: NVAL19/01 and GSK (NCT04449419)

Effect of hemodialysis session on acute changes in inflammatory and cardiovascular risk biomarkers

Background: Inflammation is associated with enhanced cardiovascular risk profile and increased cardiovascular mortality in end-stage kidney disease patients undergoing hemodialysis. Mechanisms of activated acute phase reaction in patients on chronic hemodialysis remain to be identified. As successful treatment of the inflammatory condition in these patients may improve long-term survival, we studied potential changes in different inflammatory biomarkers of cardiovascular risk in end-stage kidney disease patients after a mid-week hemodialysis session. Methods: Inflammatory biomarkers of cardiovascular risk (cystatin-C, homocysteine, C-reactive protein, procalcitonin, pentraxin-3, serum amyloid-A) and atherogenic plasma lipoproteins (Lipoprotein(a), cholesterol low and high density lipoproteins) were studied in 21 end-stage kidney disease patients previously and after a mid-week hemodialysis session. Results: We found a significant reduction in serum levels of low molecular weight molecules: cystatin-C (5.56 to 1.85 mg/L, 66.73%, p < 0.001), homocysteine (22.85 to 13.25 µmol/L, 42.01%, p < 0.001) and procalcitonin (0.788 to 0.457 ng/mL, 42.01%, p < 0.001). Large molecules as C-reactive protein (9.70 to 9.90 mg/L, 2.06%, p = 0.022) and pentraxin-3 (1.67 to 4.28 ng/mL, 156%, p < 0.001) increased, but serum amyloid-A decreased (15.90 to 12.70 mg/L, 20.13%, p < 0.05). There was no change in Lipoprotein (a) levels. Conclusion: Pentraxin-3 was a more specific inflammatory vascular marker than C-reactive protein, and the best inflammatory marker associated with hemodialysis. Homocysteine, procalcitonin and the other small proteins could be released and removed during hemodialysis session. Further studies are needed to understand the behavior and significance of these markers after successive hemodialysis

Circulating levels of mitochondrial oxidative stress-related peptides MOTS-c and Romo1 in stable COPD: a cross-sectional study

Background: MOTS-c and Romo1 are mitochondrial peptides that are modulated by oxidative stress. No previous studies have explored circulating levels of MOTS-c in patients with chronic obstructive pulmonary disease (COPD). Methods: We enrolled 142 patients with stable COPD and 47 smokers with normal lung function in an observational cross-sectional study. We assessed serum levels of both MOTS-c and Romo1 and associated these findings with clinical characteristics of COPD. Results: Compared with smokers with normal lung function, patients with COPD had lower levels of MOTS-c (p = 0.02) and higher levels of Romo1 (p = 0.01). A multivariate logistic regression analysis revealed that above-median MOTS-c levels were positively associated with Romo1 levels (OR 1.075, 95% CI 1.005–1.150, p = 0.036), but no association was found with other COPD characteristics. Below-median levels of circulating MOTS-c were associated with oxygen desaturation (OR 3.25 95% CI 1.456–8.522, p = 0.005) and walking <350 meters (OR 3.246 95% CI 1.229–8.577, p = 0.018) in six-minute walk test. Above-median levels of Romo1 were positively associated with current smoking (OR 2.756, 95% CI 1.133–6.704, p = 0.025) and negatively associated with baseline oxygen saturation (OR 0.776 95% CI 0.641–0.939, p = 0.009). Conclusions: Reduced levels of circulating MOTS-c and increased levels of Romo1 were detected in patients diagnosed with COPD. Low levels of MOTS-c were associated with oxygen desaturation and poorer exercise capacity using 6 min walk test. Romo1 was associated with current smoking and baseline oxygen saturationFunding: This study was funded by Instituto de Investigación Sanitaria of Cantabria (IDIVAL): NextVAL grant: NVAL19/01. This study received funding from GSK (NCT04449419). The funder was not involved in the study design, collection, analysis, interpretation of data, the writing of this article or the decisión to submit it for publication. GSK was provided the opportunity to review a preliminary version of this manuscript for factual accuracy, but the authors are solely responsible for final content and interpretation. Acknowledgments: We want to particularly acknowledge the patients and the Biobank Valdecilla (PT17/0015/0019) integrated in the Spanish Biobank Network for its collaboration