Auburn Research Day 2021

Carlton D. Fox 1 ; Hailey A. Parry 1 ; Christopher G. Vann 1 ; Bradley A. Ruple 1 ; Shelby C. Osburn 1 ; Casey L. Sexton 1 ; Johnathon H. Moore 1 ; Morgan A. Smith 1 ; Brian K. Ferguson 1 ; Paulo Henrique Caldeira Mesquita 1 ; Darren T. Beck 1,2 ; Kaelin C. Young 1,2 ; Andreas N. Kavazis 1,2 ; Stuart M. Phillips 3; Michael D. Roberts 1,2 1 School of Kinesiology, Auburn University, Auburn, AL, USA; 2 Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine - Auburn Campus, Auburn, AL, USA; 3 Department of Kinesiology, McMaster University, Hamilton ON, CAN B i omed i ca l Resea rch | Gr adua te / Undergr adua te St udent Skeletal Muscle Metabolic Biomarker Adaptations to High Load Versus High Volume Unilateral Resistance Training 036

Purpose: Little is known regarding how differences in resistance training volume affects biomarkers in skeletal muscle related to bioenergetics and mitochondrial physiology. Therefore, the purpose of this study was to investigate how six weeks of high-volume (HV) versus high-load (HL) resistance training affected skeletal muscle biomarkers related to the ATP-PCr and glycolysis pathways, nutrient transport and mitochondrial physiology. Methods: Previously-trained college-age males (n=15; age: 23±3 years old; training experience: 7±3 years) performed unilateral lower body training (leg press and leg extension exercises), with one leg randomly assigned to HV and the other to HL training for six weeks (three d/week). The HV training condition performed five sets of 10 repetitions at 60% of estimated one-repetition maximum (1RM) per exercise at week one – increasing sets weekly – concluding at 10 sets of 10 repetitions at 60% of 1RM per exercise at week six. The HL condition performed three sets of five repetitions at ~82% 1RM per exercise at week one – increasing intensity weekly – concluding with three sets of five repetitions at 95% 1RM per exercise at week six. Vastus lateralis (VL) muscle biopsies were taken before training (PRE), 72 hours following the last training bout (POST) and following ten days of passive recovery (PR). Western blots were performed to measure markers reflective of the ATP-PCr and glycolytic pathways (PYGM, CKM, PFK, and LDHA protein levels), nutrient transporters (LAT1 and GLUT4 protein levels), mitochondrial biogenesis markers

(citrate synthase activity levels as well as PGC-1 α , TFAM and NRF1 protein levels), and mitochondrial dynamics markers (DRP1, MFN2, PARKIN and PINK protein levels). Results: Significant condition x time interactions were observed for NRF1 (p=0.016) and DRP1 (p=0.039) where relative protein expression for both markers increased from PRE to PR (p=0.019) in the HV condition. Furthermore, a significant condition x time interaction was observed for MFN2 (p=0.014) where relative protein expression was higher in the HV condition at PR. There were no condition x time interactions or main effects of time or condition observed for CKM, PFK, LDHA, PGC-1 α , LAT1, GLUT4, TFAM, PARKIN, PINK or citrate synthase activity. Conclusion: Few differences between conditions occurred over the training period, and we speculate the lack of differences was due to either the high training status of subjects and/or a lack of appreciable difference in training volume. However, HV training did elicit more changes in markers related to mitochondrial physiology, which warrants further investigation.

Cl i n i ca l Resea rch | Gr adua te / Undergr adua te St udent The Role of FMO3 Induced Nonalcoholic Hepatic Steatosis

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Victoria Jimenez; Ian Steinke; Christopher Purvis; Nila Ghanei; Rania Mohamedelhassan; Rajesh Amin. Dept. of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn AL.

Introduction: Type 2 diabetic patients display abnormally high levels of metabolic products associated with gut dysbiosis. One such metabolite, Trimethylamine N-Oxide (TMAO), is related to increased incidence of cardiovascular diseases (CVD) in human patients. Trimethylamine (TMA), a gut metabolite, comes from the metabolic degenerative product that is produced from gut microbial metabolism. Oxidation of TMA to TMAO is observed in elevated levels of diabetics and obese patients and has a direct correlation with increased risk for major adverse cardiovascular events. Mechanistically, the liver enzyme flavine-containing monooxygenase 3 (FMO3) is significantly involved in development of TMAO and hepatic gluconeogenesis. Hypothesis: We predict that in diabetes, TMAO is significantly involved in hepatic steatosis, hepatic insulin resistance and induces significant brain neuronal dysfunction. Further, we predict that elevated levels of FMO3 maybe the central player in this process.

Results: We have observed in leptin deficient (db/db) diabetic mice an increase (>3 fold) of FMO3 when compared to wild type age (four months) matched mice. Further, in human liver cell lines (HEPG2), cells over expressing FMO3 (3-fold) resulted in significant lipid accumulation and reduced glucose uptake. These observations were compared to HEPG2 cells over-expressing FMO1 and FMO5, which showed relatively no change in steatosis or changes in glucose uptake when compared to vehicle treated HEPG2 cells. We have also observed a significant increase in TMAO in FMO3 over- expressing cells after treating with TMA. Finally, we observed an increase in steatosis in HEPG2 cells treated with TMAO. Conclusion: Our data is preliminary and further evaluation will determine the significance of FMO3 and TMAO on development of NAFLD. We are currently developing novel FMO3 inhibitors for potentially mitigating development of NASH.

27 2021 Via Research Recognit ion Day