An experimental examination on ohe effects of supplementations with palm tocotrienol-rich-fraction (TRF) and annatto Δ-tocotrienol on body weight and pre-implantation embryonic development in nicotine-treated mice

Abstract

Supplementation of vitamin E to pre-pregnant mice reduces the hazardous impact of nicotine on pregnancy outcome. There are emerging evidences on vitamin E, particularly tocotrienol (TCT), exerting some roles in pre-pregnancy body weight management and pre-implantation embryonic development. This study investigated the effects of supplementations with palm tocotrienol-rich fraction (palm-TRF) and annatto δ-TCT (> 98% purity) on the pre-partum body weight and embryonic development following nicotine treatment in mice. Thirty-six (4-6 weeks old) female mice (Mus musculus) were divided into 6 groups (G1-G6). All groups were subjected to treatments either with 3 mg/kg bw/day nicotine, 60 mg/kg bw/day palm-TRF, 60 mg/kg bw/day annatto δ-TCT or; combination of nicotine concurrently with palm-TRF or annatto δ-TCT for 7 consecutive days. Body weights were recorded daily throughout the treatment period. Superovulation was conducted on Day 7 and 9, followed with cohabitation with fertile males. Animals were euthanized 48 hours post-coitum and embryos were retrieved through uterine flushing. Selected embryos were incubated in M16 medium and observed daily. Results showed that nicotine (G2) decreased the pre-partum body weight (22.2 ± 1.1g vs 29.8 ± 0.6g) (p<0.05) and the number of cleaving embryos at all stages in G2 were significantly decreased (p<0.05) compared to control. Intervention with annatto δ-TCT attenuated the embryonic development, unlike the intervention with palm-TRF. Supplementations with palm-TRF and annatto δ-TCT alone resulted in unchanged body weight and increased in the number of retrieved hatched blastocysts. Present results suggest that future efforts in determining the regulating signaling pathways are important, and the mechanisms of actions by both nicotine and TCT could be elucidated further.