Liposome-encapsulated dextrazide modifies spleen extracellular matrix composition in mice with chronic BCG-induced inflammation

Abstract

Fibrosis of parenchymal organs is a common complication of tuberculosis. In a model of BCG-induced inflammation in mice, changes in the metabolism of the extracellular matrix (ECM) of the spleen were demonstrated with the introduction of a liposome-encapsulated dextrazide (LEDZ) containing isoniazid and oxidized dextran.The mice were divided into 4 groups: 1 – intact animals; 2 – infected mice after a single intravenous injection of BCG vaccine. 6 mo after infection, a solution of LEDZ was administered intraperitoneally to mice of group 3 for 3 mo, and inhaled to mice of group 4. Group 2 mice showed the signs of pronounced spleen fibrosis (increased content of hyaluronan, hydroxyproline fractions) with activation of hyaluronidases, matrix metalloproteinases (MMP), α2-macroglobulin and an increased content of tissue inhibitors of MMP (TIMP-1 and TIMP-2) with respect to group 1 data. In group 3, changesin the structure of proteoglycans were noted (an increase in the content of uronic acids and galactose), a decrease in the content of hyaluronan and free hydroxyproline, an increase in the activity of hyaluronidases. The MMP activity and the TIMP content corresponded to the data of group 2. In group 4, the content of uronic acids and galactose in proteoglycans also increased, but peptide-bound hydroxyproline decreased and the hyaluronan content more noticeably decreased. The activity of all enzymes regulating the ECM metabolism reduced with respect to the data of group 2.Thus, intraperitoneal administration of LEDZ to infected mice led to activating hyaluronidases, changing the structure of proteoglycans, and decreasing the free hydroxyproline content. Inhalation administration of LEDZ, along with changes in the structure of proteoglycans, reduced the activity of MMP, hyaluronidases, α2-macroglobulin, the content of TIMP-1 and TIMP-2, peptide-bound hydroxyproline. The antifibrotic effect of LEDZ with inhalation administration was manifested in a decrease in peptide-bound hydroxyproline and in a more significant decrease in hyaluronan compared with intraperitoneal administration.Thus, intraperitoneal administration of LEDZ to infected mice led to activating hyaluronidases, changing the structure of proteoglycans, and decreasing the free hydroxyproline content. Inhalation administration of LEDZ, along with changes in the structure of proteoglycans, reduced the activity of MMP, hyaluronidases, α2-macroglobulin, the content of TIMP-1 and TIMP-2, peptide-bound hydroxyproline. The antifibrotic effect of LEDZ with inhalation administration was manifested in a decrease in peptide-bound hydroxyproline and in a more significant decrease in hyaluronan compared with intraperitoneal administration.