Auburn Research Day 2022

Joshua S. Godwin 1 , Bradley A. Ruple 1 , Casey L. Sexton 1 , Morgan A. Smith 1 , Andrew D. Frugé 2 , Kaelin C. Young 1,3 , Christopher B. Mobley 1 , Michael D. Roberts 1,3 1 School of Kinesiology, Auburn University; 2 Department of Nutrition, Dietetics and Hospitality Management, Auburn University; 3 Edward Via College of Osteopathic Medicine- Auburn Campus B i omed i ca l Resea rch | Gr adua te/Undergr adua te St udent Extracellular Matrix Content and Remodeling Does Not Differ Between Higher-Responders and Lower-Responders to Resistance Training 44

Objective: To determine if markers of skeletal muscle extracellular matrix (ECM) content and ECM remodeling are indicators of hypertrophy in previously untrained collage aged males. Hypotheses: Higher-responders (HR) to resistance training would demonstrate more malleable changes in assayed ECM markers than lower-responders (LR). Methods: Untrained, college-aged males (n=38, 21±3 years old) participated in 10 weeks of full-body progressive resistance training (2x weekly) which included the leg press, bench press, leg extension, deadlift, and lat pulldown exercises. Participants completed a pre- testing battery (DXA, ultrasound, pQCT and strength testing) and donated a vastus lateralis (VL) biopsy approximately one week prior to training. Participants completed post-testing 72 hours following their last training bout, and this mimicked pre-testing. Participants were then sorted into HR (n=10) and LR (n=10) based on changes in lean body mass, mid-thigh cross-sectional area (CSA), VL thickness, and deadlift strength changes. Muscle tissue from these 20 participants were processed for western blotting targeting MMP-2, MMP-9, MMP-14, TIMP-1, TIMP-2, collagen-1, and collagen-4 protein levels. Global MMP activity was also performed on whole tissue lysates, and fascial thickness was measured from ultrasound images. All dependent variables were analyzed in SPSS (v22.0) using two-way (group*time) repeated measures ANOVAs.

Results: No significant group*time interactions or main effects of time were detected for MMP-2, MMP-9, TIMP-1, TIMP-2, Collagen-1, or Collagen-4 protein levels (p > 0.05). MMP activity and VL fascial thickness also revealed no significant group*time interactions or main effects of time (p > 0.05). A significant main effect of time (p = 0.009) and group*time interaction (p = 0.007) was detected for MMP- 14. Further analysis revealed a significant difference between HR and LR prior to training (p = 0.026) along with a significant decrease from pre to post in HR (p = 0.002) Conclusions: Our data suggest that skeletal muscle ECM markers did not differentiate higher-responders versus lower- responders to resistance training. However, MMP-14 was responsive to resistance training and significantly different between response clusters prior to resistance training, and this warrants further investigation.

Cl i n i ca l Case Repor t | Med i ca l St udent Metastatic Leptomeningeal Carcinomatosis from Primary Breast Cancer Found in a Medical School Cadaveric Dissection

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Mary-Catherine Mitchell; James Pollock; Mary Beth Downs, PhD Edward Via College of Osteopathic Medicine-Auburn Campus

Leptomeningeal carcinomatosis is an increasingly common, but still rare, complication of metastatic cancer affecting the pia and arachnoid mater of the central nervous system. It has been postulated that recent improvements in cancer patient survival time have increased the frequency of leptomeningeal carcinomatosis and other relatively rare metastatic conditions that patients previously would not have lived long enough to experience. Leptomeningeal carcinomatosis carries a universally poor prognosis with a mean survival between 2 to 4 months if treated, however, the recent increase in incidence has allowed for further research into the condition, including case reports documenting clinical findings and potential treatments. Options for administering chemotherapy have been limited in the past by the presence of the blood-brain barrier and toxic adverse effects, but recent developments in surgical placement of chemotherapeutic ports have allowed for intrathecal delivery of drugs like methotrexate to the intraventricular system and superior sagittal sinus without system exposure. In fact, innovative delivery systems

are currently undergoing clinical trials to deliver these drugs in a metronomic fashion and limit leukoencephalopathy complications of methotrexate. Currently, primary breast cancer is the most common source of metastatic leptomeningeal lesions (via hematogenous or contiguous route), and such a lesion was observed by the authors in the cadaver of a 70-year-old Caucasian female with unspecified breast cancer in a medical school lab. The body was found to have a surgically positioned Burr hole superficial to a metastatic lesion in the underlying leptomeninges. Cause of death was listed as “complication of malignant neoplasm of unspecified site.” Over the course of two case reports, one focusing on the histopathological findings of this particular cadaveric dissection and the other on current and developing treatment options for leptomeningeal carcinomatosis, we seek to develop our own understanding of this rare metastatic phenomena and highlight the importance of student cadaveric dissection, as it exposes students to rare presentations such as these.

27 2022 Via Research Recognit ion Day