1211-P: In Utero Diabetes Exposure to Diabetes Alters MicroRNA Abundance in Mesenchymal Stem Cells

Adverse intrauterine environments increase susceptibility of offspring to develop metabolic diseases later in life through epigenetic mechanisms. Studies suggest the multipotent mesenchymal stem cells (MSC) from umbilical cord Wharton’s Jelly are programmed by exposure to maternal diabetes and obesity toward adipogenesis. MicroRNAs (miRNA) are a key mechanism through which epigenetic modifications occur. We hypothesized MSCs exposed to diabetes in utero would have altered miRNA abundance, resulting in downstream effects within the adipogenesis pathway. We harvested human MSCs from control (N=11) and diabetic mellitus (DM, N=13) groups. Control group is defined as mother with normal glucose level and DM with either type 2 diabetes or gestational diabetes during pregnancy. MSCs were isolated within 24 hours of delivery and confirmed via flow cytometry by the presence of CD105 and 90 and absence of CD34 and 45. MSCs were differentiated into adipocytes. Total RNA was extracted using miRNeasy isolation kit (Qiagen, USA) and complementary DNAs (cDNA) from the RNAs were synthesized by using Advance cDNA Synthesis kits (ThermoFisher, USA). Real time PCR (RT PCR) was used to investigate differences in miRNA abundance between those groups. Data from RT PCR were analyzed by delta-delta CT (2^−ΔΔCT) method, and RNU48 was used as a reference gene. We discovered that for undifferentiated MSCs, miR-155 was 2-fold higher (p=0.02) and miR-423 was 1.3-fold higher (p=0.04) in the DM comparing to the control group. None of the miRNA in the differentiated adipocytes was different between the groups. Higher levels of miR-155 inhibits browning of fat, and miR-423 is associated with morbid obesity.

In conclusion, DM during pregnancy alters miRNA abundance in stem cells and this phenomenon may impact downstream targets and pathways leading to increased risk of metabolic disease in the offspring.