ABSTRACT
OBJECTIVES This study aims to compare the differential gene expression resulting from tocotrienol-rich fraction and α-tocopherol supplementation in healthy older adults. METHODS A total of 71 eligible subjects aged 50 to 55 years from Gombak and Kuala Lumpur, Malaysia, were divided into three groups and supplemented with placebo (n=23), α-tocopherol (n=24) or tocotrienol-rich fraction (n=24). Blood samples were collected at baseline and at 3 and 6 months of supplementation for microarray analysis. RESULTS The number of genes altered by α-tocopherol was higher after 6 months (1,410) than after 3 months (273) of supplementation. α-Tocopherol altered the expression of more genes in males (952) than in females (731). Similarly, tocotrienol-rich fraction modulated the expression of more genes after 6 months (1,084) than after 3 months (596) and affected more genes in males (899) than in females (781). α-Tocopherol supplementation modulated pathways involving the response to stress and stimuli, the immune response, the response to hypoxia and bacteria, the metabolism of toxins and xenobiotics, mitosis, and synaptic transmission as well as activated the mitogen-activated protein kinase and complement pathways after 6 months. However, tocotrienol-rich fraction supplementation affected pathways such as the signal transduction, apoptosis, nuclear factor kappa B kinase, cascade extracellular signal-regulated kinase-1 and extracellular signal-regulated kinase-2, immune response, response to drug, cell adhesion, multicellular organismal development and G protein signaling pathways. CONCLUSION Supplementation with either α-tocopherol or tocotrienol-rich fraction affected the immune and drug response and the cell adhesion and signal transduction pathways but modulated other pathways differently after 6 months of supplementation, with sex-specific responses.
Subject(s)
Humans , Male , Female , Middle Aged , Gene Expression/drug effects , Dietary Supplements , alpha-Tocopherol/pharmacology , Tocotrienols/pharmacology , Antioxidants/pharmacology , Protein Kinases/drug effects , Time Factors , Signal Transduction/drug effects , Cell Adhesion/drug effects , Single-Blind Method , Sex Factors , Gene Expression Regulation/drug effects , Oxidative Stress/drug effects , Immune System/drug effectsABSTRACT
Objective: Problem-based learning [PBL] is a student-centred learning system that involves multidisciplinary fields focused on problem solving. Facilitators of PBL are not necessarily content experts but little is known on how this concept has affected the outcomes of PBL sessions in learning Medical Biochemistry. We aimed to evaluate the impact of having the content expert as a facilitator in conducting PBL
Methods: A total of 150 first and second year medical students from the University Kebangsaan Malaysia were interviewed with a validated set of questions to acquire their views on the roles of facilitators in PBL in learning Medical Biochemistry. Their achievement were evaluated through their essay marks derived from various PBL packages
Results: All respondents agreed that PBL sessions associated with Medical Biochemistry are best appreciated when conducted by a content-expert facilitator. Their exam marks reflected well on their perception
Conclusion: PBL sessions related to Medical Biochemistry is best facilitated by Biochemistry lecturers as the content experts