Coenzyme Q10 (CoQ10) is a fat-soluble antioxidant that has long been studied in human patients with cardiovascular disease. A few studies have been performed in dogs, but none assessed the effect of CoQ10 supplementation on oxidative stress markers, inflammatory markers and lymphocyte populations in dogs of different breeds with different stages of spontaneous myxomatous mitral valve degeneration (MMVD). In addition, information on lymphocyte subpopulations in dogs in different stages of MMVD is lacking. Furthermore, there are no official recommendations on the dosage of CoQ10, and no dose-ranging studies have been done in dogs with heart disease. To investigate this, we performed a prospective cross-sectional flow cytometry study, a double-blind randomized placebo-controlled CoQ10 dose-ranging study, and a double-blind randomized placebo-controlled 3-month CoQ10 supplementation study. The results of our research showed that dogs with stable and unstable congestive heart failure (CHF) had a lower percentage of CD4+ T lymphocytes and CD4+/CD8+ ratio and a higher percentage of CD8+ T lymphocytes, and additionally, dogs in unstable CHF had higher CD8+ T lymphocyte concentration, which suggests immune system involvement in the pathogenesis and progression of CHF. A 200 mg daily dose of water-soluble CoQ10 was sufficient to achieve at least a 3-fold increase in plasma CoQ10 concentration, which enables the biological effects of CoQ10, and can be used in future CoQ10 supplementation studies in dogs with MMVD. After a 3-month supplementation with water-soluble CoQ10, a decrease in neutrophil percentage and an increase in lymphocyte count and percentage were noted in dogs with CHF due to MMVD, while there was no effect on other measured biomarkers, lymphocyte subpopulations or echocardiographic and clinical parameters in dogs with or without CHF. The results of our study suggest that CoQ10 as a dietary supplement can potentially reduce inflammation in dogs with CHF due to MMVD.
|
