Homocastasterone is a ketosteroid and a member of the brassinosteroid family of plant hormones. Earlier studies with 28-homobrasslinolide, an aldosteroid, had indicated that rat blood and tissue biochemical parameters studied were affected by this compound, resulting in altered homeostasis and cellular phosphorylation status, rendering this plant oxysterol inappropriate for high energy related work activities. The use of the ketosteroid in this study presents evidence for renormalization of elevated plasma lipid content in diabetic rat, antiglycemic potency, increase in liver glycogen and glucose level and diminished ALT and AST enzyme activities. A role for this ketosteroid in rat liver gluconeogenesis and in lipid homeostasis is suggested while the aldo and keto forms regulated glucose homeostasis in the rat. The observed differences in the effects of homobrasslinolide and homocastasterone as exogenous oxysterols on normal and diabetic rat plasma lipid level suggests the possibility of differential influence by endogenous aldo and keto oxycholesterol forms on glucose and lipid homeostasis in mammalian physiology