Stress-dependent Glucocorticoids and Proinflammatory Cytokines Impair Wound Healing

1. Stress-dependent Glucocorticoids and Proinflammatory Cytokines Impair Wound Healing Carla Cueva Biol 520 March 11th, 2009

2. Outline • Introduction • Hypothesis • Experimental findings • Summary • Conclusions • Take home message • Future experiments • References

3. What is Stress? http://www.kf6nvr.net/blog/archives/images/computing_stress.jpg

4. Stress • Stress is defined as the process through which environmental demands exceed an individual’s perceived ability to cope, thereby resulting in affective, behavioral, and physiological changes. • Stress has long been suspected to play a role in the etiology of many diseases, and numerous studies have confirmed that stress-induced disruption of neuroendocrine immune equilibrium is consequential to health. • Stress and accompanying negative emotions of anxiety and depression can provoke increases in proinflammatory cytokines that are associated with a variety of diseases. Vileikyte, 2007

5. Stess • Environmental demands or stressors are assumed to impact on health through 2 interacting routes: • (a) directly, by activating the hypothalamic-pituitary adrenal and the sympathetic-adrenal medullary axes, thereby resulting in downstream hormonal and immunologic changes, and • (b) indirectly, by inducing negative emotions, which in turn impact on physiologic processes and/or behavioral patterns that influence health. Vileikyte, 2007

6. Mechanisms by which Stress Influences Health • Physiology of stress response • Psychologic response to stress • Behavioral response to stress Vileikyte, 2007

7. Physiology of Stress Response

8. The Wound Healing Process Vileikyte, 2007

9. Connections between the nervous and immune systems Marques-Deak , 2005

10. Effects of glucocorticoids on immune-cell populations Sternberg, 2006

11. Hypothesis Glucocorticoids effects proinflammatory cytokines is the essential pathways by which stress affects wound healing

12. Experimental Findings

14. Married coupleswere admitted to a hospital research clinic Couples were subjected to both supportive and conflicting interactions Couple’s blister wounds and cytokine production (IL-6, TNFα, and IL-β) were measured Findings: Low hostile group showed ~ same (65%-70%) increase in IL-6 levels over 24 hours High hostile group showed an increase from 45% to 113% on Ill-6 levels High hostile group had higher TNF-α values before and after conflict task Hostile Marital Interactions, ProinflammatoryCytokine Production, and Wound Healing Kiecolt-Glaser et al., 2005

16. Restraint Stress Slows Cutaneous Wound Healing in Mice • Female SKH-1 mice were subjected to restraint stress (RST) on conical tube for 15 hours • Control mice were not restraint • - RST SKH-1 animals were injected subcutaneously with 25mg/kg glucocorticoid receptor antagonist RU40555 prior to RST Padgett et al., 1998

18. Androstenediol reduces the anti-inflammatory effectsof restraint stress during wound healing • CD1 male mice were subjected to RST prior to placement of cutaneous wounds. • - Both FWD and RST mice were injected with 40mg/mL AED prior to wounding. • The rate of wound closure was assessed daily by photoplanimetry. • Findings: • RST slowed wound closure • AED treatment ameliorated suppressive effects of stress FWD = food/water deprived RST = restraint stress VEH = vehicle (DMSO:EtOH) AED = androstenediol Head et al., 2006

19. Androstenediol reduces the anti-inflammatory effectsof restraint stress during wound healing • At 3, 6, 12 and 24 hours post wounding, IL-1β and PDGF RNAs were quantified by RT-PCR for inflammatory gene expression. • Findings: • Significant effect of RST treatment post injury • AED treatment ameliorated RST effect. FWD = food/water deprived RST = restraint stress VEH = vehicle (DMSO:EtOH) AED = androstenediol Head et al., 2006

21. Restraint stress impairs early wound healing in mice via α-adrenergic but not β-adrenergic receptors • - Dermal wounds by punch biopsy were placed on RST SKH-1 female mice • Prior to RST, mice were injected with either phentolamine or nadolo • Pictures were taken daily to measure wound closure/contraction • Findings: • RST induced impairments in wound size/contraction were reduced in phentolamine treated animals FWD = food/water deprived RST = restraint stress Phentolamine = non-specific α-adrenergic receptor Nadolol = non-specific β-adrenergic receptor Eijkelkamp et al., 2007

22. Restraint stress impairs early wound healing in mice via α-adrenergic but not β-adrenergic receptors • FWD and RST groups were injected intravenously with 5mg/ml Evans blue prior to wounding to measure edema formation • Findings: • Phentoalamine prevented the reduction in edema that was observed in saline treated RST mice Eijkelkamp et al., 2007

24. Experimental Models of Stress and Wound Healing • RST and social disruption (SDR) were used as stressors. • SDR: male C57BL/6 mice were introduced to aggressive intruder. • - Cutaneous punch biopsy wound was placed on control or stressed (RST or SDR) C57BL/6 animals and the kinetics of wound healing were studied over 10 days. Sheridan et al., 2004

26. Hyperbaric oxygen therapy ameliorates stress-impaired dermal wound healing • Female SKH-1 mice were subjected to RST and hyperbaric oxygen therapy (HBO) twice a day for two hours during early wound healing • 3.5mm cutaneous wound placed by punch biopsy behind shoulder and photographed • Wound inducible nitric oxide synthase (iNOS) was studied for gene expression by RT-PCR from RNA isolated from tissue Gajendrareddy et al., 2005

27. Summary

28. Conclusions • Glucocorticoid and proinflammatory cytokines are important pathways in stress-derived wound healing • However, other pathways such as SNS-dervied catecholamines (ex alpha-adrenergic receptors) are also involved in wound healing delay

29. Future Experiments • RST and SDR treatment and vice versa to measure desensitizing to GC • SDR and alpha-adrenergic receptors • Alpha-adrenergic antogonist that can cross brain-blood barrier, use different antagonist

30. Take Home Message Marques-Deak , 2005

31. References Christian, L. M., Graham, J. E., Padgett, D. A., Glaser, R., Kiecolt-Glaser, J. K. (2006). Stress and wound healing. Neuroimmunomodulation, 13, 337-346 Eijkelkamp, N., Engeland, C. G., Gajendrareddy, P. K., Marucha, P. T. (2007). Restraint stress impairs early wound healing in mice via alpha-adrenergic but not beta-adrenergic receptors. Brain, Behavior, and Immunity, 21, 409-412 Gajendrareddy, P. K., Sen, C. K., Horan, M. P., Marucha, P. T. (2005). Hyperbaric oxygen therapy ameliorates stress-impaired dermal wound healing. Brain, Behavior, and Immunity, 19, 217-222 Head, C. C., Farrow, M. J., Sheridan, J. F., Padgett, D. A. (2006). Androstenediol reduces the anti-inflammatory effects of restraint stress during wound healing. Brain, Behavior, and Immunity, 20, 590-596 Kiecolt-Glaser, J. K., Loving, T. J., Stowell, J. R., Malarkey, W. B., Lemeshow, S., Dickinson, S. L., Glaser, R. (2005). Hostile Marital Interactions, Proinflammatory Cytokine Production, and Wound Healing. Arch Gen Psychiatry, 62, 1377-1384 Padgett, D. A., Marucha, P. T., Sheridan, J. F. (1998). Restraint stress slows cutaneous wound healing in mice. Brain, Behavior, and Immunity, 12, 64-73  Rojas, I., Padgett, D. A., Sheridan, J. F., Marucha, P. T. (2002). Stress-induced susceptibility to bacterial infection during cutaneous wound healing. Brain, Behavior, and Immunity, 16, 74-84 Sheridan, J. F., Padgett, D. A., Avitsur, R., Marucha, P. T. (2004). Experimental models of stress and wound healing. World Journal of Surgery, 28, 327-330 Sternberg, E. M. (2006). Neural regulation of innate immunity: a coordinated nonspecific host response to pathogens. Nature reviews. Immunology, 6, 318–328   Vileikyte, L. (2007). Stress and wound healing. Clinics in Dermatology, 25, 49-55