The Ethyl Acetate Fraction of Torbangun (Coleus amboinicus L.) Leaves Increasing Milk Production with Up-Regulated Genes Expression of Prolactin Receptor

Abstract

This study is aimed towards determining the lactagogue effect of torbangun leaves on lactogenic hormone plasma levels and on the expression of their receptors in mammary glands of lactating rats. Lactagogue activity was evaluated by volume of milk was produced by the rats treated with commercial milk booster containing ‘katuk' leaves extract (AF), ethyl acetate fraction of torbangun leaves (EA), water extraction of torbangun leaves (AQ) and kaempferol (KP). Lactating rats (n=5) of Sprague dawley with six pups were fed with AF, EA, AQ, and KP in the amount of 50 mg/kg, 30 mg/kg, 80 mg/kg and 60 mg/kg body weight, respectively. The volume of milk was estimated by the increment in pup weight after breastfed. The levels of serum lactogenic hormones were determined by ELISA methods. To access the expression level of lactogenic hormone’s receptors in the mammary gland real time – polymerase chain reaction method was employed. The results showed that ethyl acetate fraction of torbangun leaves (EA) (a) was not significantly stim-ulating the synthesis of serum prolactin and estradiol at day 14 and day 28 lactation period, (b) down-regulated the gene expression of estradiol receptor (ERα) at day 28, and (c) up-regulated the gene expression of prolactin receptor (PRLR) in mammary gland at day 14 and day 28. This study suggests that ethyl acetate fraction of torbangun leaves was induced milk production, by up-regulating the gene expression of prolactin receptor (PRLR) in the mammary gland of lactating rats.