Gregory E Demas

Summary

Affiliation: Indiana University
Country: USA

Publications

  1. doi request reprint Beyond phytohaemagglutinin: assessing vertebrate immune function across ecological contexts
    Gregory E Demas
    Department of Biology, Center for the Integrative Study of Animal Behavior, Indiana University, 1001 E 3rd St, Bloomington, IN 47405, USA
    J Anim Ecol 80:710-30. 2011
  2. doi request reprint In vivo but not in vitro leptin enhances lymphocyte proliferation in Siberian hamsters (Phodopus sungorus)
    Gregory E Demas
    Department of Biology, Program in Neuroscience and the Center for the Integrative Study of Animal Behavior, Indiana University, 1001 E 3rd Street, Bloomington, IN 47405, USA
    Gen Comp Endocrinol 166:314-9. 2010
  3. ncbi request reprint Metabolic stress suppresses humoral immune function in long-day, but not short-day, Siberian hamsters (Phodopus sungorus)
    Devin A Zysling
    Department of Biology, Center for the Integrative Study of Animal Behavior and Program in Neuroscience, Indiana University, Bloomington, IN 47405, USA
    J Comp Physiol B 177:339-47. 2007
  4. pmc Exogenous insulin enhances humoural immune responses in short-day, but not long-day, Siberian hamsters (Phodopus sungorus)
    Nicholas W Garcia
    Department of Biology, Program in Neuroscience and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN 47405, USA
    Proc Biol Sci 277:2211-8. 2010
  5. pmc Leptin increases maternal investment
    Susannah S French
    Department of Biology, Utah State University, 5305 Old Main Hill, Logan, UT 84322, USA
    Proc Biol Sci 276:4003-11. 2009
  6. pmc The glutamate agonist NMDA blocks gonadal regression and enhances antibody response to an immune challenge in Siberian hamsters (Phodopus sungorus)
    Timothy J Greives
    Department of Biology, Center for the Integrative Study of Animal Behavior and Program in Neuroscience, Indiana University, 1001 E 3rd St, Bloomington, IN 47405 3700, USA
    J Comp Physiol B 180:267-77. 2010
  7. doi request reprint Social defeat differentially affects immune responses in Siberian hamsters (Phodopus sungorus)
    Emily M Chester
    Indiana University, Department of Biology, Center for the Integrative Study of Animal Behavior and Program in Neuroscience, Bloomington, IN 47405, USA
    Physiol Behav 101:53-8. 2010
  8. ncbi request reprint Photoperiod modulates the effects of norepinephrine on lymphocyte proliferation in Siberian hamsters
    Gregory E Demas
    Department of Biology, Indiana University, Bloomington, IN 47405, USA
    Am J Physiol Regul Integr Comp Physiol 285:R873-9. 2003
  9. pmc Exogenous kisspeptin does not alter photoperiod-induced gonadal regression in Siberian hamsters (Phodopus sungorus)
    Timothy J Greives
    Indiana University, Department of Biology, Center for the Integrative Study of Animal Behavior and Program in Neuroscience, 1001 East 3rd Street, Bloomington, IN 47405, USA
    Gen Comp Endocrinol 156:552-8. 2008
  10. pmc Leptin regulates energetic tradeoffs between body fat and humoural immunity
    Gregory E Demas
    Program in Neural Science and Center for the Integrative Study of Animal Behavior and Department of Biology, Indiana University, Bloomington, IN 47405 USA
    Proc Biol Sci 272:1845-50. 2005

Detail Information

Publications31

  1. doi request reprint Beyond phytohaemagglutinin: assessing vertebrate immune function across ecological contexts
    Gregory E Demas
    Department of Biology, Center for the Integrative Study of Animal Behavior, Indiana University, 1001 E 3rd St, Bloomington, IN 47405, USA
    J Anim Ecol 80:710-30. 2011
    ..6. By incorporating assessments of immune function into their specific research questions, animal ecologists will gain a more comprehensive understanding of organism-environment interactions...
  2. doi request reprint In vivo but not in vitro leptin enhances lymphocyte proliferation in Siberian hamsters (Phodopus sungorus)
    Gregory E Demas
    Department of Biology, Program in Neuroscience and the Center for the Integrative Study of Animal Behavior, Indiana University, 1001 E 3rd Street, Bloomington, IN 47405, USA
    Gen Comp Endocrinol 166:314-9. 2010
    ..Importantly, these findings confirm previous studies that leptin serves as an important endocrine link between energy balance and immunity...
  3. ncbi request reprint Metabolic stress suppresses humoral immune function in long-day, but not short-day, Siberian hamsters (Phodopus sungorus)
    Devin A Zysling
    Department of Biology, Center for the Integrative Study of Animal Behavior and Program in Neuroscience, Indiana University, Bloomington, IN 47405, USA
    J Comp Physiol B 177:339-47. 2007
    ..In contrast, no difference was observed between treatment groups in short days. These data suggest that reductions in energy availability suppress immunity and short days buffer organisms against glucoprivation-induced immunosuppression...
  4. pmc Exogenous insulin enhances humoural immune responses in short-day, but not long-day, Siberian hamsters (Phodopus sungorus)
    Nicholas W Garcia
    Department of Biology, Program in Neuroscience and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN 47405, USA
    Proc Biol Sci 277:2211-8. 2010
    ..Collectively, these data support the hypothesis that insulin acts as an endocrine signal integrating seasonal energetic changes and immune responses in seasonally breeding rodents...
  5. pmc Leptin increases maternal investment
    Susannah S French
    Department of Biology, Utah State University, 5305 Old Main Hill, Logan, UT 84322, USA
    Proc Biol Sci 276:4003-11. 2009
    ..Collectively, these findings suggest that leptin plays a critical role in allowing mothers to determine how much energy to invest in the production and care of young versus self-maintenance...
  6. pmc The glutamate agonist NMDA blocks gonadal regression and enhances antibody response to an immune challenge in Siberian hamsters (Phodopus sungorus)
    Timothy J Greives
    Department of Biology, Center for the Integrative Study of Animal Behavior and Program in Neuroscience, Indiana University, 1001 E 3rd St, Bloomington, IN 47405 3700, USA
    J Comp Physiol B 180:267-77. 2010
    ..In addition, these findings demonstrate a general immunoenhancing effect of NMDA that appears independent of changes in reproductive or energetic state of the animal...
  7. doi request reprint Social defeat differentially affects immune responses in Siberian hamsters (Phodopus sungorus)
    Emily M Chester
    Indiana University, Department of Biology, Center for the Integrative Study of Animal Behavior and Program in Neuroscience, Bloomington, IN 47405, USA
    Physiol Behav 101:53-8. 2010
    ..Collectively, these results contribute to our understanding of complex social behaviors and their differential effects on endocrine and immune responses in vertebrates...
  8. ncbi request reprint Photoperiod modulates the effects of norepinephrine on lymphocyte proliferation in Siberian hamsters
    Gregory E Demas
    Department of Biology, Indiana University, Bloomington, IN 47405, USA
    Am J Physiol Regul Integr Comp Physiol 285:R873-9. 2003
    ..Collectively, these results provide further support that photoperiodic changes in immunity are influenced by changes in SNS activity...
  9. pmc Exogenous kisspeptin does not alter photoperiod-induced gonadal regression in Siberian hamsters (Phodopus sungorus)
    Timothy J Greives
    Indiana University, Department of Biology, Center for the Integrative Study of Animal Behavior and Program in Neuroscience, 1001 East 3rd Street, Bloomington, IN 47405, USA
    Gen Comp Endocrinol 156:552-8. 2008
    ..Collectively, these results provide evidence that mechanisms in addition to those that converge on the kisspeptin system are likely critical for seasonal changes in the reproductive axis...
  10. pmc Leptin regulates energetic tradeoffs between body fat and humoural immunity
    Gregory E Demas
    Program in Neural Science and Center for the Integrative Study of Animal Behavior and Department of Biology, Indiana University, Bloomington, IN 47405 USA
    Proc Biol Sci 272:1845-50. 2005
    ..These results suggest that reductions in energy availability lead to impairments in humoural immunity and that leptin can serve as a neuroendocrine signal between body fat and immunity regulating humoural immune responses...
  11. doi request reprint Experimentally induced sickness decreases food intake, but not hoarding, in Siberian hamsters (Phodopus sungorus)
    Alfredo Durazzo
    Department of Biology, Center for the Integrative Study of Animal Behavior and Program in Neuroscience, Indiana University, Bloomington, IN 47405, USA
    Behav Processes 79:195-8. 2008
    ..These results support previous findings suggesting that food hoarding and food intake appear to be differentially regulated at the physiological level...
  12. ncbi request reprint Short-day increases in aggression are independent of circulating gonadal steroids in female Siberian hamsters (Phodopus sungorus)
    Melissa Ann L Scotti
    Department of Biology, Center for Integrative Study of Animal Behavior and Program in Neuroscience, Indiana University, Bloomington, IN 47405, USA
    Horm Behav 52:183-90. 2007
    ..These results also suggest that the endocrine regulation of seasonal aggression may be similar between the sexes...
  13. ncbi request reprint Aggressive encounters differentially affect serum dehydroepiandrosterone and testosterone concentrations in male Siberian hamsters (Phodopus sungorus)
    Melissa Ann L Scotti
    Department of Biology, Program in Neuroscience and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN 47405, USA
    Horm Behav 56:376-81. 2009
    ..These data suggest that nocturnal aggressive encounters rapidly increase conversion of DHEA to T and that melatonin may play a permissive role in this process...
  14. doi request reprint Leptin as a physiological mediator of energetic trade-offs in ecoimmunology: implications for disease
    Susannah S French
    Department of Biology, Utah State University, Logan, UT 84322 5305, USA
    Integr Comp Biol 51:505-13. 2011
    ..Overall, the combined results suggest that leptin serves as a proximate endocrine signal of available energy to the immune system, and therefore likely to affect susceptibility to diseases...
  15. pmc Food supplementation and testosterone interact to influence reproductive behavior and immune function in Sceloporus graciosus
    Mayté Ruiz
    Department of Biology and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN 47405, USA
    Horm Behav 57:134-9. 2010
    ..Collectively, this study shows that the energetic state of the animal plays a critical role in modulating the interactions among T, behavior and immunity in sagebrush lizards and likely other species...
  16. doi request reprint The role of androgens in the mediation of seasonal territorial aggression in male Siberian hamsters (Phodopus sungorus)
    Melissa Ann L Scotti
    Department of Biology, Center for the Integrative Study of Animal Behavior and Program in Neuroscience, Indiana University, Bloomington, IN 47405, USA
    Physiol Behav 95:633-40. 2008
    ..Further, seasonal changes in territorial aggression appear independent of circulating levels of DHEA in Siberian hamsters...
  17. pmc Recent advances in reproductive neuroendocrinology: a role for RFamide peptides in seasonal reproduction?
    Timothy J Greives
    Department of Biology, Center for the Integrative Study of Animal Behavior and Program in Neuroscience, Indiana University, Bloomington, IN 47405, USA
    Proc Biol Sci 275:1943-51. 2008
    ..Understanding the mechanisms regulating appropriate changes in reproductive status will serve to advance a wide range of life science disciplines...
  18. ncbi request reprint Splenic denervation blocks leptin-induced enhancement of humoral immunity in Siberian hamsters (Phodopus sungorus)
    Gregory E Demas
    Department of Biology, Program in Neural Science, and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, Ind 47405, USA
    Neuroendocrinology 76:178-84. 2002
    ....
  19. ncbi request reprint Social interactions differentially affect reproductive and immune responses of Siberian hamsters
    Gregory E Demas
    Department of Biology, Center for the Integrative Study of Animal Behavior, and Program in Neural Science, Indiana University, 1001 E 3rd Street, Bloomington, IN 47405, USA
    Physiol Behav 83:73-9. 2004
    ..These data support the notion of social-stress-induced suppression of immune humoral and cell-mediated immune responses...
  20. pmc Response to exogenous kisspeptin varies according to sex and reproductive condition in Siberian hamsters (Phodopus sungorus)
    Timothy J Greives
    Department of Biology, Indiana University, Bloomington, IN 47405, USA
    Gen Comp Endocrinol 170:172-9. 2011
    ..Collectively, these data provide further insight into the basic actions of kisspeptin in the regulation of reproduction and provide a potential mechanism for the regulation of differential reproductive responses between the sexes...
  21. ncbi request reprint The energetics of immunity: a neuroendocrine link between energy balance and immune function
    Gregory E Demas
    Department of Biology, Indiana University, Bloomington, IN 47405, USA
    Horm Behav 45:173-80. 2004
  22. ncbi request reprint Adrenal hormones mediate melatonin-induced increases in aggression in male Siberian hamsters (Phodopus sungorus)
    Gregory E Demas
    Department of Biology, Program in Neural Science, and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN 47405, USA
    Horm Behav 46:582-91. 2004
    ....
  23. ncbi request reprint Environmental control of kisspeptin: implications for seasonal reproduction
    Timothy J Greives
    Department of Biology, Center for the Inregrative Study of Animal Behavior, Indiana University, 1001 East 3rd Street, Bloomington, IN 47405, USA
    Endocrinology 148:1158-66. 2007
    ....
  24. doi request reprint Leptin, a neuroendocrine mediator of immune responses, inflammation, and sickness behaviors
    Elizabeth D Carlton
    Department of Biology, Program in Neuroscience and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN 47405, USA
    Horm Behav 62:272-9. 2012
    ....
  25. pmc Human disturbance alters endocrine and immune responses in the Galapagos marine iguana (Amblyrhynchus cristatus)
    Susannah S French
    Department of Biology, Utah State University, Logan, UT 84322, USA
    Horm Behav 58:792-9. 2010
    ..The study also broadens the foundation of knowledge needed to understand the global significance of various levels of human disturbance...
  26. pmc Reductions in total body fat decrease humoral immunity
    Gregory E Demas
    Department of Biology, Program in Neural Science, and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN 47405, USA
    Proc Biol Sci 270:905-11. 2003
    ..There was no significant increase in EWAT in IWATx hamsters compared with sham animals and IgG remained significantly reduced in IWATx hamsters. These results suggest that reductions in energy availability can impair humoral immunity...
  27. ncbi request reprint Behavioral and physiological responses to experimentally elevated testosterone in female dark-eyed juncos (Junco hyemalis carolinensis)
    Devin A Zysling
    Department of Biology, Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN 47405, USA
    Horm Behav 50:200-7. 2006
    ..We discuss these results in the context of potential endocrine-immune interactions and the evolution of sexual dimorphism...
  28. ncbi request reprint Photoperiodic regulation of gene expression in brown and white adipose tissue of Siberian hamsters (Phodopus sungorus)
    Gregory E Demas
    Center for Behavioral Neuroscience, Department of Biology, Georgia State University, Atlanta, Georgia 30303 3083, USA
    Am J Physiol Regul Integr Comp Physiol 282:R114-21. 2002
    ..Thus the SD-induced decreased adiposity of Siberian hamsters may be due to a coordinated suite of WAT and BAT gene transcription changes ultimately increasing lipid mobilization and utilization...
  29. pmc Examining sources of variation in HPG axis function among individuals and populations of the dark-eyed junco
    Christine M Bergeon Burns
    Department of Biology and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN 47405, USA Electronic address
    Horm Behav 65:179-87. 2014
    ..Testis mass, but not LH receptor transcript abundance, predicted individual variation in T responses. These data implicate the gonad, but not the pituitary, as an important source of individual variation in T production. ..
  30. doi request reprint Ecological immunology: The organism in context
    Susannah S French
    Department of Biology, Utah State University, Logan UT, 84322 School of Life Sciences, Arizona State University, Tempe AZ 85287 Department of Biology, Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington IN 47405, USA
    Integr Comp Biol 49:246-53. 2009
    ..Akin to Dobzhansky's famous line, like other aspects of biology, nothing in ecoimmunology seems to make sense except in the context of an organism's environment...
  31. ncbi request reprint Vasopressin cell groups exhibit strongly divergent responses to copulation and male-male interactions in mice
    Jacqueline M Ho
    Department of Biology, Indiana University, Bloomington, IN 47405, USA
    Horm Behav 58:368-77. 2010
    ..These findings greatly expand what is known of the contributions of specific brain AVP cell groups to social behavior...