Chirathanaphirom Suphakan, Chuammitri Phongsakorn, Pongkan Wanpitak, Manachai Nawin, Chantawong Pinkarn, Boonsri Burin, Boonyapakorn Chavalit
Cardiopulmonary Clinic, Small Animal Hospital, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50200, Thailand.
Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand.
Animals (Basel). 2023 Dec 14;13(24):3850. doi: 10.3390/ani13243850.
Myxomatous mitral valve disease (MMVD) is the most common heart disease in small-breed dogs, often leading to heart failure. Oxidative stress in MMVD can harm mitochondria, decreasing their DNA content. This study assesses dogs' oxidative stress and mitochondrial DNA at different MMVD stages. Fifty-five small-breed dogs were categorized into four groups, including: A-healthy ( = 15); B-subclinical ( = 15); C-heart failure ( = 15); and D-end-stage MMVD ( = 10). Serum malondialdehyde (MDA) and mitochondrial DNA in peripheral blood were analyzed. Quantitative real-time PCR measured mitochondrial DNA, and PCR data were analyzed via the fold-change Ct method. Serum MDA levels were assessed using competitive high-performance liquid chromatography (HPLC). Mitochondrial DNA was significantly lower in group B (-0.89 ± 2.82) than in group A (1.50 ± 2.01), but significantly higher in groups C (2.02 ± 1.44) and D (2.77 ± 1.76) than B. MDA levels were notably elevated in groups B (19.07 ± 11.87 µg/mL), C (23.41 ± 12.87 μg/mL), and D (19.72 ± 16.81 μg/mL) in comparison to group A (9.37 ± 4.67 μg/mL). Nevertheless, this observed difference did not reach statistical significance. It is noteworthy that mitochondrial DNA content experiences a decline during the subclinical stage but undergoes an increase in cases of heart failure. Concurrently, oxidative stress exhibits an upward trend in dogs with MMVD. These findings collectively suggest a potential association between mitochondrial DNA, oxidative stress, and the progression of MMVD in small-breed dogs.
黏液瘤样二尖瓣疾病（MMVD）是小型犬中最常见的心脏病，常导致心力衰竭。MMVD中的氧化应激会损害线粒体，降低其DNA含量。本研究评估了不同MMVD阶段犬的氧化应激和线粒体DNA。55只小型犬被分为四组，包括：A组-健康犬（n = 15）；B组-亚临床期（n = 15）；C组-心力衰竭（n = 15）；D组-终末期MMVD（n = 10）。分析了外周血中的血清丙二醛（MDA）和线粒体DNA。采用定量实时PCR检测线粒体DNA，并通过Ct值变化倍数法分析PCR数据。使用竞争性高效液相色谱法（HPLC）评估血清MDA水平。B组（-0.89±2.82）的线粒体DNA显著低于A组（1.50±2.01），但C组（2.02±1.44）和D组（2.77±1.76）的线粒体DNA显著高于B组。与A组（9.37±4.67μg/mL）相比，B组（19.07±11.87μg/mL）、C组（23.41±12.87μg/mL）和D组（19.72±16.81μg/mL）的MDA水平显著升高。然而，观察到的这种差异未达到统计学意义。值得注意的是，线粒体DNA含量在亚临床阶段下降，但在心力衰竭病例中增加。同时，MMVD犬的氧化应激呈上升趋势。这些发现共同表明线粒体DNA、氧化应激与小型犬MMVD进展之间可能存在关联。
