التفاصيل البيبلوغرافية
العنوان: |
Albumin is an important factor in the control of serum free fatty acid flux in both male and female mice. |
المؤلفون: |
Tomoo, Keigo, Szramowski, Mirandia, Pinal, Rodolfo, Meyer, Juliauna M., Zhang, Yi, Murray-Kolb, Laura E., Henderson, Gregory C. |
المصدر: |
Journal of Applied Physiology; May2024, Vol. 136 Issue 5, p1065-1075, 11p |
مصطلحات موضوعية: |
FREE fatty acids, LIPOLYTIC enzymes, MICE, KNOCKOUT mice, ALBUMINS, ADIPOSE tissues |
مستخلص: |
Albumin knockout (Alb−/−) mice exhibit a low plasma free fatty acid (FFA) concentration, but it was not known if the suppressed concentration reflects a lower rate of appearance (Ra) of FFA in the circulation (i.e., lower FFA flux) or if the absence of albumin alters the relationship between FFA flux and concentration. For understanding the role of albumin in FFA transport through the bloodstream, it is not sufficient to rely on FFA concentration data alone. Therefore, we developed a method to study FFA kinetics in Alb−/− mice. Using an albumin-free formulation of [U-13C]palmitate tracer, serum FFA kinetics were tested in Alb−/− and wild-type (WT) mice. Results indicate that the flux of FFA in serum of Alb−/− mice was significantly lower than in WT mice (P < 0.05), while albumin deficiency did not alter the relationship between FFA flux and concentration. Next, to test if suppressed lipolysis might have also been involved in the suppressed FFA kinetics, gene expression of a lipolytic enzyme (adipose triglyceride lipase, Atgl) and a marker of lipolysis (phosphorylation of hormone-sensitive lipase, p-HSL) were measured in adipose tissue. In contrast to the low FFA flux in Alb−/−, both Atgl gene expression and p-HSL protein were significantly higher in adipose tissue of Alb−/− than in WT mice (P < 0.05). Thus, the low FFA flux in Alb−/− appeared to be driven by the absence of albumin's FFA binding functions rather than through regulation of lipolysis, indicating that albumin is an important factor in determining the flux of FFA in circulation. NEW & NOTEWORTHY: To improve understanding of the albumin protein's function in vivo, we tested plasma free fatty acid kinetics in albumin knockout mice compared with wild-type mice. Using a new tracer formulation strategy, it was discovered that the appearance rate of free fatty acids in serum is lower in albumin knockout mice than in wild-type mice. The results indicate that albumin is a major controller of free fatty acid kinetics. [ABSTRACT FROM AUTHOR] |
|
Copyright of Journal of Applied Physiology is the property of American Physiological Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) |
قاعدة البيانات: |
Complementary Index |