No abstract

Heat-shock protein concentrations in the blood increase after exposure to a variety of stressors, including trauma and psychological stress. Although the physiological function of extracellular heat shock protein remains controversial, there is evidence that extracellular heat shock protein 72 (Hsp72) can facilitate immunologic responses. The signal(s) that mediate(s) the in vivo elevation of extracellular Hsp72 in the blood after stressor exposure remain(s) unknown. Here we report that Hsp72 increases in the circulation via an alpha1-adrenergic receptor-mediated signaling pathway. Activation of alpha1-adrenoceptors results in a rapid increase in circulating Hsp72, and blockade of alpha1-adrenoceptors prevents the stress-induced rise in circulating Hsp72. Furthermore, our studies exclude a role for beta-adrenoceptors, glucocorticoids, and ACTH in mediating stress-induced elevations in circulating extracellular Hsp72. Understanding the signals involved in elevating extracellular Hsp72 could facilitate the use of extracellular Hsp72 to bolster immunity and perhaps prevent exacerbation of inflammatory diseases during stress.

Acute relapses continue to be a significant aspect of multiple sclerosis (MS) on both the epidemiologic level and the individual patient level. Past work demonstrates residual disability from relapses as well as high patient-reported rates of ineffective relapse treatment. To better characterize the impact of MS relapses on the patient, a relapse-specific survey was administered through the North American Research Committee on Multiple Sclerosis (NARCOMS) Registry to 1000 registry participants who had reported at least one relapse in the past 12 months. Thirty percent of respondents confirmed lack of relapse treatment efficacy at one month and at three months. Relapses also impacted socioeconomic measures; for individuals still going to school or working, more than half missed days and their average loss of school or work was 12.7 days. An impact on household tasks was reported by 68% of respondents. A healthcare facility such as a hospital, emergency room or urgent care center was utilized by 20.4% of respondents. The most common relapse symptoms were fatigue, weakness of the lower extremity, sensory symptoms, problems walking, and weakness of the upper extremity. Of the respondents who reported receiving corticosteroid treatment (53.3%), over half reported an adverse event. However, this was not a significant factor in dictating whether or not respondents would seek a different treatment on their next relapse, although 31% would choose a different treatment for their next relapse. Relapses continue to be an impactful experience that requires continued clinical attention. Improved follow-up from relapses and relapse treatment might be beneficial.

It is difficult to predict when patients will respond favorably to CSs, both in terms of therapeutic response and tolerability profile. There are specific cellular, systemic, and clinical characteristics that might merit further consideration when utilizing CSs in clinical practice, and these should be explored in a translational setting.

The majority of previous work examining stress responses has been done in males. Recently, it has become clear that the impact of stressor exposure is modulated by sex. One stress response that may be affected by sex is the induction of intracellular heat shock protein (HSP) 72, which is a stress- responsive molecular chaperone that refolds denatured proteins and promotes cellular survival. The following study compared HSP72 in males and females and also examined whether the estrous cycle altered HSP72 induction in females. We hypothesized that females compared with males would have a constrained HSP72 response after an acute stressor and that the stress-induced HSP72 response in females would fluctuate with the estrous cycle. Male and female F344 rats were either left in their home cage or exposed to acute tail-shock stress (8-10/group). Immediately following stressor, trunk blood was collected and tissues were flash frozen. Vaginal smear and estrogen enzyme immunoassay were used to categorize the phase of estrous. Results show that female rats had a greater corticosterone response than males, that both males and females exhibit a stress-induced release of progesterone, and that males and females had equal levels of stress-induced circulating norepinephrine. Sexual dimorphism of the HSP72 (ELISA) response existed in pituitary gland, mesenteric lymph nodes, and liver such that female rats had an attenuated HSP72 response compared with males after stress. The adrenal glands, spleen, and heart did not exhibit sexual dimorphism of the HSP72 response. The estrous cycle did not have a significant effect on basal or stress-induced HSP72 in females.