Therapeutic efficiency of dimephosphone and xydiphone in experimental pulse therapy with prednisolone.

Experiments on rats showed that pulse therapy with prednisolone (100 mg/kg intraperitoneally for 3 days) stimulated urinary excretion of hydroxyproline, increased the content of inorganic phosphorus, promoted the increase in the content of dienic conjugates and catalase activity, and decreased serum levels of MDA and ceruloplasmin. Ten-day treatment with dimephosphone (208 mg/kg) or xydiphone (45 mg/kg) after pulse therapy with prednisolone normalized urinary excretion of hydroxyproline and reduced the levels of dienic conjugates. Dimephosphone did not change, while xydiphone normalized the level of MDA decreased by prednisolone.

[Effect of dimephosphon and xydiphone on mineral metabolism and lipid peroxidation in rats subjected to "pulse-therapy" with prednisolone]. / Vliianie dimefosfona i ksidifona na mineral'nyi obmen i perekisnoe okislenie lipidov krys na modeli "pul's-terapii" prednizolonom.

The parameters of mineral metabolism, a lipid peroxidation (LPO) process, and the efficacy of antioxidant enzyme preparations were studied in rats with an osteoporosis model induced by the administration of prednisolone in a daily dose of 100 mg/kg (i.p.) over 3 days, which is analogous to a pulsed therapy schedule in clinics. The treatment with glucocorticosteroid enhanced the excretion of hydroxyproline and inorganic phosphates with urine, increased the LPO rate and antioxidant activity of the blood serum, and decreases the level of ceruloplasmin and the catalase activity in the blood. A prophylactic treatment with dimephosphon (208 mg/kg, p.o.) and xydiphone (45 mg/kg, p.o.) prevents from the prednisolone-induced LPO activation. Dimephosphon, in contrast to xydiphone, also prevents from a prednisolone-induced increase in the excretion of hydroxyproline and inorganic phosphates with urine.

[Effect of dimephosphon and xidifon on parameters of lipid peroxidation and the antioxidant system in rats subjected to the long-term administration of prednisolone]. / Vliianie dimefosfona i ksidifona na pokazateli perekisnogo okisleniia lipidov i antioksidantnoi sistemy krys, dlitel'no poluchavshikh prednizolon.

Experiments in rats with an osteoporosis model induced by the chronic administration of prednisolone (50 mg/kg, p.o., over 14 days) showed that the drug differently affects the lipid peroxidation (LPO) rate and the antioxidant system activity. Xydiphone (45 mg/kg, p.o.) administered over 14 days exhibited a perooxidant action. Dimephosphon (208 mg/kg, p.o.) administered over the same period of time produced an antioxidant effect as manifested by a growth in the catalase activity, an increase in the content of ceruloplasmin and glutathione, and a decrease in the content of LPO products in the blood serum and liver tissues. The results of combined administration of prednisolone and phosphonates indicate good prospects of the dimephosphon treatment as a means of normalization of the LPO and antioxidant system functioning disturbed by prolonged use of glucocorticoids.

[Comparative study of the effect of dimephosphon monophosphonate and xydiphone biphosphonate on the histomorphometric indices of rat vertebra in a model of glucocorticosteroid osteoporosis]. / Sravnitel'noe izuchenie vliianiia monofosfonata dimefosfona i bifosfonata ksidifona na gistomorfometricheskie pokazateli stroeniia pozvonkov krys pri modelirovanii gliukokortikosteroidnogo osteoporoza.

The efficacy of monophosphonate dimephosphon and diphosphonate xydiphon was compared by experiments in rats with an osteoporosis model induced by the chronic administration of prednisolone. The glucocorticosteroid decreased the total density of trabecules (in both bone and cartilage tissues) in histological micropreparations of lumbar vertebrae and reduced the total bone cell count and the calcium content in the bone tissue. Dimephosphon, administered on the prednisolone background over the same period of time, normalized the total relative density of trabecules (by increasing the cartilage content), the total bone cell count, and the calcium content. Under the same conditions, xydiphone normalized the total relative density of trabecules (by increasing the bone content), but did not influence the prednisolone-decreased content of cartilage, total cell count, and calcium content in the vertebrae. Thus, the test results reveal a significant advantage of dimephosphon over xydiphone.