CONCLUSIONS Poison oak changes the immune-related miRNAs profile of milk exosomes: Poison oak affect milk composition Yes Few miRNAs affected metabolism Yes Pasteurization amount and affect proportion of miRNAs from milk exosomes. all RNA Proportion specific miRNA affected cancer and metabolism why?? Emily Sahagun 1 , Jimmy Bell 2 , Jennifer Belveal 1 , Sarah Akers 1 , Randi Wilson 1 , Chelsey Naito 1 , Claudia Ingham 1 , Lisbeth Goddik 3 , David Hendrix 2 , Duo Jiang 4 , and Massimo Bionaz 1 INTRODUCTION Urushiol, the allergen present in Toxicodendron diversilobum (western poison oak), is responsible for contact dermatitis. More than 70% of adults have a reaction to urushiol, making this an important problem in the Northwest of the US. There is a popular belief that consumption of milk from goats fed with poison oak provides resistance to allergic contact dermatitis. MicroRNAs (miRNAs) are small 18-25nt RNAs functioning in post-transcriptional regulation. miRNAs are horizontally transferred between cells in the same organism; it is also possible they could be transferred between organisms. Milk has a large number of exosomes containing miRNAs that are highly enriched for immune-related function. Therefore, it is possible that the putative beneficial effect of milk from goats fed poison oak is due to changes in miRNAs content of exosomes in goat’s milk. PILOT STUDY Goal: to assess the fate of urushiol in lactating dairy goats fed with poison oak. Two lactating Saanen goats weighing 70±2 kg were housed with their triplets at the OSU Sheep Center. Their pens were divided into a feeding area and social area. Milk yield of the does was 3.3± 0.7 kg per day. Poison oak was presented to the adult females at 8 am and 6 pm daily, separate from the kids, in raised feeders. The goats were fed up to 2 kg of poison oak at each feeding. They were offered 2.8 kg of orchard grass, 2.5 kg Alfalfa, and 1.3 kg whole corn plus minerals at 11 am and 8 pm each day. RESULTS No urushoil was found in blood, milk, or plasma of the goats fed poison oak. MATERIALS AND METHODS LITERATURE CITED Gartner, B. L., C. Wasser, E. Rodriguez, and W. L. Epstein. 1993. Seasonal Variation of Urushiol Content in Poison Oak Leaves. Dermatitis 4:33-36. Kouakou, B., D. Rampersad, E. Rodriguez, and D. L. Brown. 1992. Dairy goats used to clear poison oak do not transfer toxicant to milk. California Agriculture 46(3):4-6 ACKNOWLEDGMENTS The research was supported by the Agricultural Research Foundation (OR). Grant#8283A Luigi and Caroline Meneghelli of Inavale farm 8 AM and 6 PM goats were isolated from the kids for 3 hours and up to 2 kg of Poison oak was provided . Daily dry matter intake of poison oak was recorded Animals were fed twice a day ( 11 AM and 8 PM) with 2 . 8 kg Orchard grass, 2 . 5 kg Alfalfa, and 1 . 3 kg whole corn plus minerals RESULTS AND DISCUSSION 1 Department of Animal and Rangeland Sciences, Oregon State University, OR, 97331, USA 3 Department of Food Science & Technology, Oregon State University, OR, 97331, USA 2 Department of Biochemistry and Biophysics, Oregon State University, OR, 97331, USA 4 Statistics Department, Oregon State University, OR, 97331, USA Main findings: Poison oak affect piRNAs Pasteurization proportion of piRNAs Poison oak was freshly collected from Inavale Farm (Philomath, OR) each 2 - 3 days OBJECTIVE To assess the effect of feeding poison oak on 1) milk yield and composition, and 2) abundance of various miRNA in milk exosomes. Furthermore, an additional objective was to assess the effect of pasteurization on abundance of various miRNA in milk exosomes. The poison oak did not affect milk yield, total solid in the milk, the energy content of the milk, overall feed intake of the goats or the kids, and the body weight of the kids; however, several parameters of the milk were affected by poison oak. Feeding poison oak also negatively affected body weight (76.1 vs. 74.1 in control vs. poison oak fed goats, p<0.01). Feeding poison oak affected did not affect the expression of miRNA, but piwi associated RNA (piRNA) expression was affected. Pasteurization decreased significantly the levels of piRNA Heptadecylcatechol Heptadecenylcatechol Heptadecadienylcatechol Heptadecatrienylcatechol URUSHOIL COMPOSITION Out of 431 annotated goat miRNA we identified 98 present in all samples ng RNA/mL milk (log 2 ) Control Poison Oak 4.0 4.5 5.0 5.5 6.0 6.5 7.0 Pasteurized Raw a a b b Total reads (log 2 ) 20 21 22 23 24 25 a a b miRNA hit (log 2 ) 10 12 14 16 18 20 Pasteurization No No Yes Poison Oak Yes No No No No Yes Yes No No Pasteurization significantly decreased total RNA isolated from milk exosomes Pasteurization significantly decreased total sequence reads of RNA isolated from milk exosomes, but did not affect the total amount of annotated miRNA