Apolipoprotein A1 distribution pattern in the human Achilles tendon

We examined the distribution of Apo‐A1 protein in biopsies from normal and tendinopathy‐affected human Achilles tendons, and APOA1 mRNA production from cultured human hamstring tenocytes. Specific immunoreactions for Apo‐A1 were detected. The tenocytes showed specific Apo‐A1 immunoreactions. These reactions were usually distinct in the tendinopathy specimens. While the tendinopathy specimens often showed granular/small deposit reactions, the slender tenocytes of control specimens did not show this pattern. The magnitude of Apo‐A1 immunoreactivity was especially marked in the tendinopathy specimens, as there is a high number of tenocytes. Reactions were also seen in the walls of blood vessels located within the tendon tissue proper of both the normal and tendinopathy tendons and within the peritendinous/fatty tissue of the tendinopathy tendons. The reactions were predominantly in the form of deposit reactions within the smooth muscle layer of the vessel walls. Cultured hamstring tenocytes produced APOA1 mRNA. We demonstrated the presence of Apo‐A1 in human tendon tissue. This suggests there may be a link between Achilles tendinopathy and cholesterol metabolism. We hypothesize that Apo‐A1 may be important for tenocyte and blood vessel function within tendons.
Source: Scandinavian Journal of Medicine and Science in Sports - Category: Sports Medicine Authors: Tags: ORIGINAL ARTICLE Source Type: research