The binuclear form of dinitrosyl iron complexes with thiol-containing ligands in animal tissues.

It has been established that treatment of mice with sodium nitrite, S-nitrosoglutathione and the water-soluble nitroglycerine derivative isosorbide dinitrate (ISDN) as NO donors initiates in vivo synthesis of significant amounts of EPR-silent binuclear dinitrosyl iron complexes (B-DNIC) with thiol-containing ligands in the liver and other tissues of experimental mice. This effect is especially apparent if NO donors are administered to mice simultaneously with the Fe-citrate complex. Similar results were obtained in experiments on isolated liver and other mouse tissues treated with gaseous NО in vitro and during stimulation of endogenous NO synthesis in the presence of inducible NO synthase.

[Mono- and Binuclear Dinitrosyl Iron Complexes with Thiol-containing Ligands in Various Biosystems].

It has been shown that dinitrosyl iron complexes with thiol-containing ligands, bound with modified bovine serum albumin with high amount of thiol groups, appeared in baker yeast or in animal tissues in the presence of exogenous or endogenous nitric oxide, respectively, are represented predominantly by EPR-silent binuclear form. This form can be transformed into EPR-active mononuclear form of dinitrosyl iron complexes with an increase in pH to basic values, into EPR-active form of mononuclear iron nitrosyl complexes in case of bielectronic recovery of the binuclear form of dinitrosyl iron complexes or under the action of dithiocarbamate derivatives. The latter induced the transformation of dinitrosyl iron complexes into EPR-active mononitrosyl iron complexes with dithiocarbamates.

[Physico-chemistry of dinitrosyl iron complexes with thiol-containing ligands underlying their beneficial treatment of endometriosis].

Exogenous dinitrosyl iron complexes (DNIC) with thiol-containing ligands as NO and NO+ donors are capable of exerting both regulatory and cytotoxic effects on diverse biological processes similarly to those characteristic of endogenous nitric oxide. Regulatory activity of DNIC (vasodilation, hypotension, trombosis suppression, red blood cell elasticity increasing, skin wound healing acceleration, penile erection inducing, etc) is determined by their capacity of NO and NO+ transfer to biological targets of the latter (hemo- and thiol-containing proteins, respectively) due to higher affinity of the proteins for NO and NO+ than that of DNIC. Cytotoxic activity of DNIC is endowed with rapid DNIC decomposition under action of iron-chelating compounds resulting in appearance of NO and NO+ in cells and tissues in high amount.

The effect of dinitrosyl iron complexes with glutathione and S-nitrosoglutathione on the development of experimental endometriosis in rats: a comparative studies.

It has been established that intraperitoneal bolus administration of S-nitrosoglutathione (GS-NO) (12.5μmoles/kg; 10 injections in 10 days), beginning with day 4 after transplantation of two 2-mm autologous fragments of endometrial tissue onto the inner surface of the abdominal wall of rats with surgically induced (experimenta) endometriosis failed to prevent further growth of endometrioid (EMT) and additive tumors, while treatment of animals with dinitrosyl iron complexes (DNIC) with glutathione (12.5μmoles/kg, 10 injections in 10 days) suppressed tumor growth virtually completely.

Dinitrosyl iron complexes with glutathione suppress experimental endometriosis in rats.

Dinitrosyl iron complexes (DNIC) with glutathione exert a cytotoxic effect on endometrioid tumours in rats with surgically induced experimental endometriosis. Intraperitoneal treatment of rats (Group 1) with DNIC (12.5μmoles/kg, daily, for 12 days), beginning with day 4 after the surgical operation (implantation of two 2mm-thick uterine fragments onto the abdominal wall) followed by 14-day keeping of animals on a standard feeding schedule (without medication) resulted in complete inhibition of the growth of endometrioid implants (EMI) in the majority of experimental animals.