Bone Abstracts

Surgical removal of the stomach (gastrectomy, Gx) leads to osteopenia in animals and in humans. In the rat, Gx causes loss of calvaria and trabecular bone, which can be reduced by 2-oxoglutaric acid (2-Ox), a precursor of hydroxyproline the most abundant amino acid in bone collagen. The purpose of this study was to investigate the effects (if any) of Gx on articular cartilage and if dietary 2-Ox can protects against eventual adverse effects of Gx. Twenty female Sprague–Dawley rats were subjected to Gx and divided between two groups: Gx_2-Ox in the drinking water and Gx_Vehicle (i.e. drinking water without 2-Ox). Another 20 rats were shamoperated and divided between two groups: Sham_2-Ox and Sham_Vehicle. The daily dose of 2-Ox was 0.43 g/100 g rat. All the rats were killed 8 weeks later and the femora and tibiae were collected. The histology and histomorphometry analyses of articular cartilage from knee joints were done. Gx caused significant decrease of total thickness and superficial, intermediate and deep zone thickness of articular cartilage. The effect of Gx was evident in tibia and less pronounced in femur. Gx also affected the structure, decreased density and changed the spatial distribution of thick and thin collagen fibers especially in tibia deep articular layer. 2-Oxoglutaric acid prevented the reduction in the total thickness and superficial as well as intermediate zones thickness of tibia, showing also slight increasing effect in femur articular cartilage which was not significantly affected by Gx. 2-Ox also abolished spatial changes of collagen distribution and structure caused by Gx. Gastrectomy affects articular cartilage quantitatively and qualitatively on the structural level acting selectively on particular bone, however, there are functional foods, namely 2-oxoglutaric acid, that can abolish these effects, most probably, by accelerating of collagen synthesis.