Roberto Refinetti - US grants

Refinetti 9507452 Physiological variables such as body temperature are normally buffered against changes by homeostatic regulatory responses. However, there is a normal daily fluctuation in body temperature that is driven by a circadian biological clock. It is presently unclear how the clock mechanism interacts with the systems that normally keep body temperature constant in order to produce the daily temperature fluctuations. With this CAREER award, Dr. Refinetti will lead a research team of undergraduates to investigate the interactions between the brain's circadian clock and the thermoregulatory system. He will also devote time to the development of an integrated teaching program in biological psychology. ***

[unreadable] DESCRIPTION (provided by applicant): As an Academic Research Enhancement Award project, this project aims at enhancing biomedical and behavioral research conducted at an institution of higher education that has not been a major recipient of NIH support in the past. Research funds will support the principal investigator's continuing research activities, will strengthen the institution's research environment, and will provide undergraduate students with the benefit from exposure to and participation in research. The research project will investigate a sensory mechanism ("dark adaptation") of great importance for the understanding of the process by which circadian rhythms are synchronized by the daily cycle of light and darkness ("entrainment"). The specific aims are to investigate whether several mammalian species exhibit the process of circadian dark adaptation recently demonstrated in golden hamsters and mice, to evaluate whether circadian dark adaptation is a sensory process similar to that well established in the visual system, and to determine whether circadian dark adaptation occurs peripherally or centrally. The knowledge that will be gained through this project will advance the current understanding of the mechanism of entrainment. Entrainment is a process of utmost importance for animals and humans living under natural conditions, where the timing of behavioral and physiological processes must be coordinated with the daily alternation of day and night. A better understanding of entrainment has potential applications in the prevention of jet lag and the malaise associated with shift work, the treatment of sleep disorders and depression, the scheduling of optimal times for administration of medicines, and the planning of astronaut schedules for space exploration.

Living beings require energy to survive and thrive. According to the traditional homeostatic view, animals and humans spend metabolic energy at a constant rate, just like a light bulb spends electrical energy, so that energy expenditure can be expressed in units of watts. For the last 50 years, much research has been conducted on variations in physiological processes that take place during the course of a day. This body of research suggests that the traditional homeostatic view may be incorrect. Because the natural alternation of day and night imposes on most animals a daily cycle of food availability, mating opportunities, and so on, it seems that energy expenditure may be regulated on a daily (circadian) basis rather than on a constant-rate (homeostatic) basis. According to this hypothesis, which diverges from a long tradition in physiology, metabolic rate would be properly expressed not in units of joules per second (i.e., in watts) but in units of joules per circadian cycle. The present project will evaluate this hypothesis experimentally through studies on laboratory animals. Knowledge to be gained from this project is particularly relevant to the design of special workplaces, such as submarines and underground facilities, and to the understanding of metabolic adjustments associated with the yearly seasons in livestock as well as in humans. In more general terms, knowledge on the circadian modulation of energy expenditure has potential applications in the prevention of jet lag and the malaise associated with shift work, the treatment of sleep disorders and depression, and the timing for effective administration of medicines. The project will also enhance the research environment at the grantee institution. An enhanced institutional environment that improves faculty and student research opportunity will lead to direct student experience and training in research as well as to increased involvement of the PI in research in his discipline, which in turn will lead to improved student preparation. The composition of the affected student population will be approximately 60% female and 45% ethnic minority. The results of the project will be disseminated to the scientific community by publication of articles in peer-reviewed professional journals and to the population at large by summaries published in research reports issued by the university and by synopses posted on the web site of the principal investigator's laboratory, which receives over 5,000 visitors each year.

The one-day Workshop on Chronobiology in Sao Paulo, Brazil, brings together junior and senior scientists from countries throughout the Americas, and offers an opportune environment for the exchange and discussion of the latest topics in chronobiology, the study of biological rhythms such as sleep-wake adaptations to solar cycles. The workshop also serves to identify relevant research topics and approaches that are addressed particularly well in the context of international collaborative work. The award provides support to US-based principal investigators to participate in this workshop. The intellectual merit of the workshop derives from its small size, which promotes interactions between participants, the assembly of many top scientists in chronobiology, the international make-up of the participants, and its temporal and spatial contiguity with the 13th biannual Latin American Symposium on Chronobiology. With the Latin American foreign partnership as well as a strong representation of women among session chairs and speakers, the workshop provides opportunity for outreach to populations underrepresented in science. The close, intensive interactions with senior members in the field afforded by this highly interactive workshop offer learning and networking opportunity for the many trainees and junior faculty participating in this event.

The workshop includes 4 roundtable sessions, each consisting of 4 brief presentations followed by a thorough discussion, and one keynote presentation. The roundtable topics include molecular as well as network, and circadian as well as sleep-focused themes. The collection of presentations spans a complementary range of topics and experimental systems with considerable promise for impactful activities. In addition to engendering a fertile ground for the development of new collaborations between US and Latin American laboratories, the format of the workshop and the composition of speakers and roundtable chairs foster broadening participation in STEM disciplines as well as exchange of ideas across professional levels and ethnic diversity. These aspects, combined with the workshop's central goal of exchanging and advancing exciting new ideas in chronobiology, constitute long-term benefits for the larger Chronobiology community.