Author
YANG, JIAN - Baylor College Of Medicine | |
FARMER, LISA - Rice University | |
MCALEXANDER, MELISSA - Johns Hopkins University | |
WITWER, KEN - Johns Hopkins University | |
HIRSCHI, KENDAL - Children'S Nutrition Research Center (CNRC) |
Submitted to: Plant Biology Annual Meeting
Publication Type: Abstract Only Publication Acceptance Date: 6/1/2014 Publication Date: 7/12/2014 Citation: Yang, J., Farmer, L., Mcalexander, M., Witwer, K., Hirschi, K.D. 2014. Delivery and detection of dietary plant-based miRNAs in animal tissues [abstract]. 2014 Plant Biology Annual Meeting, July 12-16, 2014, Portland, Oregon. RNA Biology, P34001-A, p. 437. Interpretive Summary: Technical Abstract: It has been proposed that genetic material, namely microRNAs (miRNAs), consumed in plant-based diets can affect animal gene expression. Though deep sequencing reveals the low-level presence of plant miRNAs in animal tissues, many groups have been thus far unable to replicate the finding that a rice miRNA (miR168) can transverse the gut, survive digestion, circulate through the bloodstream, and localize to a target organ to influence mammalian gene expression. Though we have also failed to reproduce these results, we have identified dietary and chemical means that allow plant-based miRNAs to be detected at appreciably higher levels in sera of consuming animals than previously reported. We subjected about 8-week-old mice to a feeding regimen based on chow containing a Chinese herbal remedy, honeysuckle (Lonicera japonica), for multiple days and subsequently gavage fed them a concentrated extract of honeysuckle tea. Using RT-qPCR, we quantified the levels of circulating small RNAs endogenous to the herbal tea and exogenously supplemented miR168 to demonstrate their presence in sera, urine, and exudates in responding animals only hours after gavaging. We consistently detected sera miRNA fold-changes in the thousands in approximately 15-20% of the animals. Blood chemistries revealed that miRNA absorption consistently coincided with kidney damage in the responding animals, which we replicated using a chemotherapeutic compound known to cause acute renal failure. Digital drop PCR was used to confirm the specificity of our detection. To demonstrate delivery and function of plant-based miRNAs in mammalian tissues, we have constructed transgenic plants expressing siRNAs that target transcripts encoding blood-clotting factors (Complement 3 and Clotting Factor VII), the effect of which can be rapidly monitored by ELISA with minimal affect on the animal. Our studies may produce a mechanism by which plant-based diets can be modified to create novel therapeutic approaches. |