Low-selenium diet, bone, and articular cartilage in rats.

The pathophysiology of secondary osteoarthritis remains largely obscure. Our attention has been drawn to Kashin-Beck disease (KBD), which has been attributed to Se deficiency. To obtain information regarding the prevention, prediction of progression, and treatment of this condition, we performed histological and biochemical studies on bone and articular cartilage specimens obtained from rats fed a low-Se diet. A low-Se diet was prepared and fed to Wistar rats for 3-11 mo, after which the rats were killed under general anesthesia, and their articular cartilages were studied microscopically and electron microscopically. The bone mineral density (BMD) of the femur was determined by the microdensitometry method and ash weight. In addition, serum Se, Ca, P, Alk Phos, T3, T4, and urinary Se were measured. In the low-Se group, impaired weight gain was observed from the 5th mo, and head alopecia was found in 60% of the animals. Microscopically, no clear changes in the articular chondrocytes were apparent, whereas with the electron microscope, chondrocytes in the deep layer showed degeneration of nuclei and endoplasmic reticular ballooning. From the 5th mo, a decrease in BMD (ash weight) was noted. Serum Se concentrations, alkaline phosphatase activity, and urine Se concentrations were decreased in the Se-deficient rats, whereas serum Ca, P, T3, and T4 values did not differ from those of a control group. Also, a decrease in sulfotransferase activity, which is involved in transfer in the process of synthesis of glycosaminoglycan, which is a proteoglycan carbohydrate chain, was found.(ABSTRACT TRUNCATED AT 250 WORDS)