Effect of hyperhomocysteinemia on proteolytic activity in the spleen

Abstract

The aim of the study was to investigate the effect of hyperhomocysteinemia (HC) on proteolytic activity in the spleen of rats. Methods: Albino nonlinear male rats of different ages (young, adults, and old) were involved in the study. HC was induced by intragastric administration of DL-homocysteine thiolactone. The total proteolytic activity was evaluated using casein as a substrate. The activity of metal-dependent and serine proteases was determined using proteases inhibitors ethylenediaminetetraacetic acid and phenylmethylsulfonyl. The levels of matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), and cytokines were measured by enzyme-linked immunosorbent assay. The fraction of serine proteases was isolated by affinity chromatography. Results: HC causes an increase in the total proteolytic activity, which is due to an increase in the activity of proteases of various catalytic types (serine, cysteine, aspartic proteases, and metal-dependent enzymes). The levels of MMP-2, MMP-3, MMP-8, and MMP-10 were significantly reduced in the spleen of adult and old rats and were at the control level in young rats. A disorder of the balance between MMP-1 and TIMP-1 in the spleen of rats with HC in favor of the active form of MMP-1 was revealed. At the same time, the level of serine proteases was increased in the spleen of rats of all groups. A decrease in the level of some pro-inflammatory cytokines was also revealed. Conclusions: HC causes disturbances in the proteolytic balance, manifested by an increase in proteolytic activity. The pathogenesis of this disease is not associated with the development of inflammation in the spleen.