Life Sciences Commons^™

Peripheral Clock Disruption And Metabolic Disease: Moving Beyond The Anatomy To A Functional Approach, Gabriella M. Marino, Deanna M. Arble

Biological Sciences Faculty Research and Publications

Sleep and circadian disruption are associated with an increased risk of metabolic disease, including obesity and diabetes. Mounting evidence indicates that misaligned and/or non-functional clock proteins in peripheral tissues critically contribute to the presentation of metabolic disease. Many of the foundational studies which led to this conclusion have focused on specific tissues such as the adipose, pancreas, muscle, and liver. While these studies have greatly advanced the field, the use of anatomical markers to manipulate tissue-specific molecular clocks may not be representative of the circadian disruption that occurs within the clinical population. In this manuscript, we argue that investigators can …

Rates Of Performance Loss And Neuromuscular Activity In Men And Women During Cycling: Evidence For A Common Metabolic Basis Of Muscle Fatigue, Christopher W. Sundberg, Sandra K. Hunter, Matthew W. Bundle

Exercise Science Faculty Research and Publications

The durations that muscular force and power outputs can be sustained until failure fall predictably on an exponential decline between an individual’s 3-s burst maximum to the maximum performance they can sustain aerobically. The exponential time constants describing these rates of performance loss are similar across individuals, suggesting that a common metabolically based mechanism governs muscle fatigue; however, these conclusions come from studies mainly on men. To test whether the same physiological understanding can be applied to women, we compared the performance-duration relationships and neuromuscular activity between seven men [23.3 ± 1.9 (SD) yr] and seven women (21.7 ± 1.8 …

Impact Of Sleep And Circadian Disruption On Energy Balance And Diabetes: A Summary Of Workshop Discussions, Deanna M. Arble, Joseph Bass, Cecilia Diniz Behn, Matthew P. Butler, Etienne Challet, Charles Czeisler, Christopher M. Depner, Joel Elmquist, Paul Franken, Michael A. Grandner, Erin C. Hanlon, Alex C. Keene, Michael J. Joyner, Ilia Karatsoreos, Philip A. Kern, Samuel Klein, Christopher J. Morris, Allan I. Pack, Satchidananda Panda, Louis J. Ptacek, Naresh M. Punjabi, Paolo Sessone-Corsi, Frank A. Scheer, Richa Saxena, Elizabeth R. Seaquest, Matthew S. Thimgan, Eve Van Cauter, Kenneth P. Wright

Biological Sciences Faculty Research and Publications

A workshop was held at the National Institute for Diabetes and Digestive and Kidney Diseases with a focus on the impact of sleep and circadian disruption on energy balance and diabetes. The workshop identified a number of key principles for research in this area and a number of specific opportunities. Studies in this area would be facilitated by active collaboration between investigators in sleep/circadian research and investigators in metabolism/diabetes. There is a need to translate the elegant findings from basic research into improving the metabolic health of the American public. There is also a need for investigators studying the impact …

Metabolic Effects Of Bariatric Surgery In Mouse Models Of Circadian Disruption, Deanna M. Arble, Darleen A. Sandoval, Fred W. Turek, Stephen C. Woods, Randy J. Seeley

Biological Sciences Faculty Research and Publications

Background/Objectives:

Mounting evidence supports a link between circadian disruption and metabolic disease. Humans with circadian disruption (for example, night-shift workers) have an increased risk of obesity and cardiometabolic diseases compared with the non-disrupted population. However, it is unclear whether the obesity and obesity-related disorders associated with circadian disruption respond to therapeutic treatments as well as individuals with other types of obesity.

Subjects/Methods:

Here, we test the effectiveness of the commonly used bariatric surgical procedure, Vertical Sleeve Gastrectomy (VSG), in mouse models of genetic and environmental circadian disruption.

Results:

VSG led to a reduction in body weight and fat mass in …

Mechanisms Underlying Weight Loss And Metabolic Improvements In Rodent Models Of Bariatric Surgery, Deanna M. Arble, Darleen A. Sandoval, Randy J. Seeley

Biological Sciences Faculty Research and Publications

Obesity is a growing health risk with few successful treatment options and fewer still that target both obesity and obesity-associated comorbidities. Despite ongoing scientific efforts, the most effective treatment option to date was not developed from basic research but by surgeons observing outcomes in the clinic. Bariatric surgery is the most successful treatment for significant weight loss, resolution of type 2 diabetes and the prevention of future weight gain. Recent work with animal models has shed considerable light on the molecular underpinnings of the potent effects of these ‘metabolic’ surgical procedures. Here we review data from animal models and how …

Sex Differences In Human Fatigability: Mechanisms And Insight To Physiological Responses, Sandra K. Hunter

Exercise Science Faculty Research and Publications

Sex-related differences in physiology and anatomy are responsible for profound differences in neuromuscular performance and fatigability between men and women. Women are usually less fatigable than men for similar intensity isometric fatiguing contractions. This sex difference in fatigability, however, is task specific because different neuromuscular sites will be stressed when the requirements of the task are altered, and the stress on these sites can differ for men and women. Task variables that can alter the sex difference in fatigability include the type, intensity and speed of contraction, the muscle group assessed and the environmental conditions. Physiological mechanisms that are responsible …

Rna Unwinding By The Trf4/Air2/Mtr4 Polyadenylation (Tramp) Complex, Huijue Jia, Xuying Wang, James T. Anderson, Eckhard Jankowsky

Biological Sciences Faculty Research and Publications

Many RNA-processing events in the cell nucleus involve the Trf4/Air2/Mtr4 polyadenylation (TRAMP) complex, which contains the poly(A) polymerase Trf4p, the Zn-knuckle protein Air2p, and the RNA helicase Mtr4p. TRAMP polyadenylates RNAs designated for processing by the nuclear exosome. In addition, TRAMP functions as an exosome cofactor during RNA degradation, and it has been speculated that this role involves disruption of RNA secondary structure. However, it is unknown whether TRAMP displays RNA unwinding activity. It is also not clear how unwinding would be coordinated with polyadenylation and the function of the RNA helicase Mtr4p in modulating poly(A) addition. Here, we show …