胆汁酸(BA)的合成和分泌是肝脏的关键生理功能。在门体分流术等病理条件下,肝功能不全,肝炎,或肝硬化BA代谢和分泌受到干扰。总血清BA的定量是评估一般肝功能并允许早期检测异常的既定诊断方法,肝病进展和治疗决策指导。迄今为止,关于狗的比较BA谱的数据是有限的。然而,BA谱可能是比总BA浓度更好的诊断参数。在这个背景下,本研究分析和比较了血清中的个别BA谱,等离子体,尿液,10只健康幼犬和40只成年健康犬的粪便使用超高效液相色谱耦合电喷雾电离质谱。样品制备通过固相萃取进行血清,等离子体,和尿液样本或用甲醇沉淀粪便样本的蛋白质。对于每一只狗,22个不同的BA,包括未缀合的BA及其甘氨酸和牛磺酸缀合物,进行了分析。总的来说,单个BA的浓度存在很大的个体差异,主要的例子是,胆酸(CA)是迄今为止一些狗(成人和幼犬)的血液和尿液样本中最突出的BA,而在别人,CA在检测极限以下。BA资料中没有显著的年龄相关差异,但是幼崽在血清中显示出一般较低的绝对BA浓度,等离子体,还有尿液.牛磺酸结合的BA在幼犬(68%)和成人(74-75%)的血清和血浆中占主导地位,而未结合的BA在幼犬的尿液和粪便中占主导地位(64%和95%,分别)和成年人(68%和99%,分别)。主要的BA鹅脱氧胆酸和牛磺胆酸以及次要的BA脱氧胆酸和石胆酸是用于潜在诊断目的的最可靠的分析物。总之,这项研究同时报道了狗血清中的BA谱,等离子体,尿液,和粪便,并为随后在患有不同类型肝脏疾病的狗中进行的临床研究提供有价值的诊断数据。
Synthesis and secretion of bile acids (BA) is a key physiological function of the liver. In pathological conditions like portosystemic shunt, hepatic insufficiency, hepatitis, or cirrhosis BA metabolism and secretion are disturbed. Quantification of total serum BA is an established diagnostic method to assess the general liver function and allows early detection of abnormalities, liver disease progression and guidance of treatment decisions. To date, data on comparative BA profiles in dogs are limited. However, BA profiles might be even better diagnostic parameters than total BA concentrations. On this background, the present study analyzed and compared individual BA profiles in serum,
plasma, urine, and feces of 10 healthy pups and 40 adult healthy dogs using ultra-high performance liquid chromatography coupled to electrospray ionization mass spectrometry. Sample preparation was performed by solid-phase extraction for serum,
plasma, and urine samples or by protein precipitation with methanol for the feces samples. For each dog, 22 different BA, including unconjugated BA and their glycine and taurine conjugates, were analyzed. In general, there was a great interindividual variation for the concentrations of single BA, mostly exemplified by the fact that cholic acid (CA) was by far the most prominent BA in blood and urine samples of some of the dogs (adults and pups), while in others, CA was under the detection limit. There were no significant age-related differences in the BA profiles, but pups showed generally lower absolute BA concentrations in serum,
plasma, and urine. Taurine-conjugated BA were predominant in the serum and
plasma of both pups (68%) and adults (74-75%), while unconjugated BA were predominant in the urine and feces of pups (64 and 95%, respectively) and adults (68 and 99%, respectively). The primary BA chenodeoxycholic acid and taurocholic acid and the secondary BA deoxycholic acid and lithocholic acid were the most robust analytes for potential diagnostic purpose. In conclusion, this study reports simultaneous BA profiling in dog serum,
plasma, urine, and feces and provides valuable diagnostic data for subsequent clinical studies in dogs with different kinds of liver diseases.