Johnson Philip J
Veterinary Medical Teaching Hospital at Clydesdale Hall, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA.
Vet Clin North Am Equine Pract. 2002 Aug;18(2):271-93. doi: 10.1016/s0749-0739(02)00006-8.
Certain management practices tend to promote the development of obesity (metabolic syndrome) in mature horses as they enter their teenage years. These management practices include the provision of starch-rich (high glycemic index) and fat-supplemented rations to healthy horses that are relatively inactive. Some horse breeds and ponies appear to be genetically predisposed to metabolic syndrome. The accretion of intra-abdominal adiposity by equids is associated with the development of insulin insensitivity (hyperinsulinemia), glucose intolerance, dyslipidemia, hypertension, and insidious-onset laminitis. Omental adipocytes are metabolically active, secreting free fatty acids and hormonally active mediators including cortisol, leptin, and resistin that might contribute to persistence and worsening of insulin refractoriness and the obese phenotype. We have hypothesized that obesity-associated laminitis arises as a consequence of vascular changes and a hypercoagulable state, similar to the development of atherosclerosis in human type 2 diabetes. Several molecular mechanisms that might serve to explain the development of insulin insensitivity as a result of excessive adiposity have been incriminated. Little investigation into the relationship between obesity, insulin insensitivity, and laminitis in horses has been reported to date. Insulin sensitivity and glucose tolerance can be improved by dietary restriction and exercise aimed at reversing omental obesity. Management practices that promote the development of obesity are likely initiated during the first 10 years of the horse's life. Veterinarians and horse owners must recognize that mature-onset obesity in adult horses is associated with a risk for development of laminitis. Obesity and insulin insensitivity might be prevented if horse owners can be educated to feed rations with a relatively lower glycemic index to inactive horses. Investigative research pertaining to the development of antiobesity drugs for human patients is continuing. Greater than 30 new pharmaceuticals are in various stages of research. However, it will likely take many years before any of these drugs are shown to be useful and safe in horses. Lifestyle changes in the form of diet and exercise patterns are still the crux of therapy for both human and equine patients.
某些管理方式往往会促使成年马在步入青少年时期后患上肥胖症（代谢综合征）。这些管理方式包括向相对不活跃的健康马匹提供富含淀粉（高血糖指数）和添加脂肪的日粮。一些马种和小型马似乎具有代谢综合征的遗传易感性。马属动物腹内脂肪的堆积与胰岛素不敏感（高胰岛素血症）、葡萄糖耐量异常、血脂异常、高血压以及隐匿性发作的蹄叶炎的发生有关。网膜脂肪细胞具有代谢活性，会分泌游离脂肪酸以及包括皮质醇、瘦素和抵抗素在内的激素活性介质，这些物质可能会导致胰岛素抵抗的持续存在和恶化以及肥胖表型。我们推测，与肥胖相关的蹄叶炎是血管变化和高凝状态的结果，类似于人类2型糖尿病中动脉粥样硬化的发展。已经有几种可能解释肥胖导致胰岛素不敏感的分子机制被牵连出来。迄今为止，关于马的肥胖、胰岛素不敏感和蹄叶炎之间关系的研究很少。通过饮食限制和旨在逆转网膜肥胖的运动，可以改善胰岛素敏感性和葡萄糖耐量。促进肥胖发展的管理方式可能在马生命的头10年就开始了。兽医和马主必须认识到成年马成年后发生的肥胖与蹄叶炎的发生风险有关。如果能够教育马主给不活跃的马匹喂食血糖指数相对较低的日粮，肥胖和胰岛素不敏感可能是可以预防的。针对人类患者的抗肥胖药物的研发研究仍在继续。超过30种新药物正处于不同的研究阶段。然而，在这些药物被证明对马有用且安全之前，可能还需要很多年。饮食和运动模式形式的生活方式改变仍然是人类和马类患者治疗的关键。
