Tissue Distribution of Prednisone/Prednisolone is Affected by TCM Danmo Capsule in Rats

Abstract

Danmo Capsule (DMC) is a patent Chinese botanic drug, widely used in combinational therapy with prednisone in China to treat renal diseases. The combined therapy regimen can reduce the dosage of glucocorticoids and relieve symptoms of glucocorticoid related adverse drug effects. Previous study from our laboratory showed that co-administration of the DMC significantly increased the plasma Cmax and AUC of glucocorticoid in rats. However, the effect of DMC on prednisone/prednisolone tissue distribution remains unclear. Therefore, the purpose of the current research was to study the tissue distribution of prednisone/prednisolone in rats after DMC was co-administered. Rats were treated with control vehicle or DMC (0.432 g kg–1) for 14 days before prednisone acetate (42 mg kg–1) was orally given. Samples from the heart, liver, spleen, lung, kidney, brain, fat, muscle, testes, small intestine and thymus were collected at different time points. The concentrations of prednisone and prednisolone were determined by high-performance liquid chromatography. Compared with prednisone alone group, the prednisone concentrations in rat lung, kidney, heart, muscle, small intestine and fat were increased in DMC treated groups, while those in liver, spleen, brain and thymus were decreased. However, the prednisolone concentrations in liver, lung, small intestine and thymus were increased, while those in kidney, fat, muscle, testes and heart were decreased following DMC pre-treatment. These results indicated that the alteration of prednisone/prednisolone levels in important tissues, when DMC was co-administered, may contribute to the effect of DMC in reducing adverse drug reactions of glucocorticoid and lowering its dosage administered.