University of Kentucky
Bmal1-/- Mice as a Model for Temporal Mandibular Joint and Muscle Disorder
Institution
University of Kentucky
Faculty Advisor/ Mentor
Karyn Esser
Abstract
Temporal Mandibular Joint and Muscle Disorder (TMJMD) affects a significant portion of the population, being especially prevalent amongst women. It is a complex set of chronic diseases related to the temporal mandibular joint and surrounding tissues. These diseases can have comorbidities that include facial pain, irritable bowel syndrome, sleep disorders, migraines and many others. Currently, molecular understanding of the disease is not fully understood. The ultimate goal is to obtain a comprehensive understanding for the onset and prevention of the disease. Bmal1 (Brain muscle ARNT like 1) is a core circadian rhythm gene that is necessary for maintenance of the molecular clock in all cell types. Previous studies have shown limb muscle in Bmal knockout mice is phenotypically altered. They have decreased force capacity and large decreases in mitochondrial volume. The hypothesis for this study is that the masseter muscle in Bmal1 knockout mice will also have decreased function leading to TMJMD. The masseter is the largest muscle of the masticatory system and is directly involved in articulation of the TMJ. This hypothesis would link the disease to circadian factors and begin to reveal the molecular mechanisms of the etiology and muscle pathology. Specifically, this study will compare function of single fibers from the masseter of Bmal1 knockout mice and wild type mice. Histological aspects of the study will assess mitochondria volume and sarcomere structure and biochemical studies will determine quantities and isoforms of important structural proteins in muscle.
Bmal1-/- Mice as a Model for Temporal Mandibular Joint and Muscle Disorder
Temporal Mandibular Joint and Muscle Disorder (TMJMD) affects a significant portion of the population, being especially prevalent amongst women. It is a complex set of chronic diseases related to the temporal mandibular joint and surrounding tissues. These diseases can have comorbidities that include facial pain, irritable bowel syndrome, sleep disorders, migraines and many others. Currently, molecular understanding of the disease is not fully understood. The ultimate goal is to obtain a comprehensive understanding for the onset and prevention of the disease. Bmal1 (Brain muscle ARNT like 1) is a core circadian rhythm gene that is necessary for maintenance of the molecular clock in all cell types. Previous studies have shown limb muscle in Bmal knockout mice is phenotypically altered. They have decreased force capacity and large decreases in mitochondrial volume. The hypothesis for this study is that the masseter muscle in Bmal1 knockout mice will also have decreased function leading to TMJMD. The masseter is the largest muscle of the masticatory system and is directly involved in articulation of the TMJ. This hypothesis would link the disease to circadian factors and begin to reveal the molecular mechanisms of the etiology and muscle pathology. Specifically, this study will compare function of single fibers from the masseter of Bmal1 knockout mice and wild type mice. Histological aspects of the study will assess mitochondria volume and sarcomere structure and biochemical studies will determine quantities and isoforms of important structural proteins in muscle.