What Mothers Eat Matters

1. 100 80 60 Mother fed a balanced diet 40 Mother fed a high-fat diet during pregnancy 20 0 27 29 31 33 35 37 39 Age (days) What Mothers Eat Matters Percentage of offspring who have reached puberty Jane Cunningham, Avondale College Teacher Fellow 2008, hosted by the Liggins Institute, University of Auckland Mothers fed high- fat diet from birth Evidence suggests our health is influenced by conditions we experienced in our mother’s womb How did we measure potential fertility? Back in the classroom... Females are born with a limited number of eggs; all waiting halfway through meiosis. Each month some will go through four developmental stages and be ready for fertilisation. We counted the number of eggs developing in each treatment group to determine whether diet influenced egg development. This research provides an interesting context for many skills and concepts: Research already suggests that if our mother ate a high-fat diet when pregnant it increases our risk of obesity, diabetes and heart disease later in life - even if we eat a healthy diet! Mother ate balanced diet Mother ate high-fat diet • Examples in Junior Science: • Nature of science: experimental design, using animal models and ethical issues • Food and digestion: importance of a healthy diet • Reproduction : early puberty and the problems this can cause for our teenagers. Mother ate high-fat diet only during pregnancy Do maternal diets also influence reproduction? Studying this relationship using a rat model • Examples in Year 13 Biology: • How the environment affects our phenotype by changing gene expression • Hormones and the control of gene expression in eukaryotes • How biotechnologies are being used in current research • Epigenetics and how it is changing our understanding of inheritance and evolution. A mature antral egg follicle ready to be released for fertilisation An egg at the primordial stage The primary stage The secondary stage We use rats as a model for how humans work because we can control their diet and they quickly have many offspring. Rats are also very similar to humans physiologically. Results Mothers always ate high- fat diet Mothers ate a balanced diet Mothers ate high- fat diet when pregnant Results suggest pregnant rats fed a high-fat diet programmed their daughters to go through puberty early and also use up their eggs more quickly. For more information or resources, please email me: cng@avcol.school.nz Daughters fed a balanced diet Daughters fed a high fat diet Daughters fed a balanced diet Daughters fed a high-fat diet Daughters fed a balanced diet Daughters fed a high- fat diet With many women making choices about nutrition during pregnancy, high-fat diets may be contributing to difficulties getting pregnant and also harm their babies long term health. We also investigated low-fat diets Some of the rats weighed up to 1.5kg! Analysing changes in gene expression could explain these differences in egg development Jane Cunningham teaches science, biology and chemistry at Avondale College. Age at puberty Acknowledgements This graph demonstrates that if pregnant rats are fed a high-fat diet during pregnancy and lactation their pups will go into puberty earlier. This may be the case in human studies. So, is the fertility of these children affected?  Thanks very much to the government-funded NZ Mathematics and Sciences Teacher fellowship scheme, administered by the Royal Society of NZ, that has allowed me to contribute to this research. I have had fantastic support from the scientists at the Liggins Institute, my host Dr Deborah Sloboda in particular; without her enthusiasm and encouragement I could not have done any of this! Also, a huge thank you to Jacquie Bay and Helen Mora for opportunities to participate in their amazing LENS programme. Crush up the ovaries and extract all the RNA. Use gel electrophoresis to check that cDNA is not contaminated Copy the RNA into cDNA which is more stable Use quantitative PCR to calculate differences in gene expression across the rat groups Use PCR to make multiple copies of the cDNA