Congestive heart failure (CHF) has been associated with depleted myocardial coenzyme Q10 (Q10) concentrations in human patients. The aim of this study was to investigate associations between myocardial Q10 concentrations and myxomatous mitral valve disease (MMVD) severity in dogs. Furthermore, citrate synthase (CS) activity was analysed to determine if a reduction in myocardial Q10 was associated with mitochondrial depletion in the myocardium. Thirty Cavalier King Charles spaniels (CKCS) in MMVD stages B1 (n = 11), B2 (n = 5) and C (n = 14) according to the American College of Veterinary Internal Medicine (ACVIM) guidelines and 10 control (CON) dogs of other breeds were included. Myocardial Q10 concentration was analysed in left ventricular tissue samples using HPLC-ECD. CKCS with congestive heart failure (CHF; group C) had significantly reduced Q10 concentrations (median, 1.54 µg/mg; IQR, 1.36–1.94), compared to B1 (2.76 µg/mg; 2.10–4.81, p < 0.0018), B2 (3.85 µg/mg; 3.13–4.46, p < 0.0054) and CON dogs (2.8 µg/mg; 1.64–4.88, p < 0.0089). CS activity was comparable between disease groups. In conclusion, dogs with CHF due to MMVD had reduced myocardial Q10 concentrations. Studies evaluating antioxidant defense mechanisms as a therapeutic target for treatment of CHF in dogs are warranted.

中文翻译：

---

骑士国王查尔斯猎犬身上的心肌辅酶Q10耗尽，患有粘液瘤性二尖瓣疾病引起的充血性心力衰竭

充血性心力衰竭（CHF）与人类患者贫血的心肌辅酶Q10（Q10）浓度有关。这项研究的目的是调查犬中心肌Q10浓度与粘液性二尖瓣疾病（MMVD）严重程度之间的关联。此外，分析了柠檬酸合酶（CS）活性，以确定心肌Q10的降低是否与心肌线粒体的耗竭有关。MMVD阶段B1（n = 11），B2（n = 5）和C（n的30个骑士国王查尔斯猎犬（CKCS）= 14）根据美国兽医内科学院（ACVIM）指南，其中包括10个其他品种的对照（CON）狗。使用HPLC-ECD分析左心室组织样品中的心肌Q10浓度。与B1（2.76 µg / mg; 2.10–4.81，p <0.0018）相比，B2伴充血性心力衰竭的CKCS（CHF; C组）的Q10浓度显着降低（中位数，1.54 µg / mg; IQR，1.36–1.94）。（3.85 µg / mg； 3.14-4.46，p <0.0054）和CON狗（2.8 µg / mg； 1.64-4.88，p < 0.0089 ）。疾病组之间的CS活性相当。总之，由于MMVD而患有CHF的狗的心肌Q10浓度降低。评估抗氧化剂防御机制作为治疗犬CHF的治疗靶点的研究是必要的。