scholarly journals Transdermal neuromodulation of noradrenergic activity suppresses psychophysiological and biochemical stress responses in humans

2015 ◽  
Author(s):  
William J. Tyler ◽  
Alyssa M. Boasso ◽  
Hailey M. Mortimore ◽  
Rhonda S. Silva ◽  
Jonathan D. Charlesworth ◽  
...  

We engineered a transdermal neuromodulation approach that targets peripheral (cranial and spinal) nerves and utilizes their afferent pathways as signaling conduits to influence brain function. We investigated the effects of this transdermal electrical neurosignaling (TEN) method on sympathetic physiology in human volunteers under different experimental conditions. In all cases, the TEN involved delivering high-frequency pulsed electrical currents to ophthalmic and maxillary divisions of the right trigeminal nerve (V1/V2) and cervical spinal nerve afferents (C2/C3). Under resting conditions when subjects were not challenged or presented with environmental stimuli, TEN significantly suppressed basal sympathetic tone compared to sham as indicated by functional infrared thermography of facial temperatures. In a different experiment conducted under similar resting conditions, subjects treated with TEN reported significantly lower levels of tension and anxiety on the Profile of Mood States scale compared to sham. In a third experiment when subjects were experimentally stressed by a classical fear conditioning paradigm and a series of time-constrained cognitive tasks, TEN produced a significant suppression of heart rate variability, galvanic skin conductance, and salivary α-amylase levels compared to sham. Collectively these observations demonstrate TEN can dampen basal sympathetic tone and attenuate sympathetic activity in response to acute stress induction. Our physiological and biochemical observations are consistent with the hypothesis that TEN modulates noradrenergic signaling to suppress sympathetic activity. We conclude that dampening sympathetic activity in such a manner represents a promising approach to managing daily stress.

Author(s):  
Carol A. Shively ◽  
Susan E. Appt ◽  
Haiying Chen ◽  
Stephen M. Day ◽  
Brett M. Frye ◽  
...  

AbstractPersistent psychological stress increases the risk of many chronic diseases of aging. Little progress has been made to effectively reduce stress responses or mitigate stress effects suggesting a need for better understanding of factors that influence stress responses. Limited evidence suggests that diet may be a factor in modifying the effects of stress. However, long-term studies of diet effects on stress reactive systems are not available, and controlled randomized clinical trials are difficult and costly. Here we report the outcomes of a controlled, randomized preclinical trial of the effects of long-term consumption (31 months, ∼ equivalent to 9 human years) of Western versus Mediterranean - like diets on behavioral and physiological responses to acute (brief social separation) and chronic (social subordination) psychosocial stress in 38 adult, socially-housed, female cynomolgus macaques. Compared to animals fed a Western diet, those fed the Mediterranean diet exhibited enhanced stress resilience as indicated by lower sympathetic activity, brisker and more overt heart rate responses to acute stress, more rapid recovery, and lower cortisol responses to acute psychological stress and adrenocorticotropin (ACTH) challenge. Furthermore, age-related increases in sympathetic activity and cortisol responses to stress were delayed by the Mediterranean diet. Population level diet modification in humans has been shown to be feasible. Our findings suggest that population-wide adoption of a Mediterranean-like diet pattern may provide a cost-effective intervention on psychological stress and promote healthy aging with the potential for widespread efficacy.HighlightsThere is no population level treatment to reduce stress and associated disease.Mediterranean diet reduced sympathetic activity.Mediterranean diet reduced cortisol response to acute stress and to ACTH challenge.Mediterranean diet delayed age-related increases in sympathetic activity and cortisol responses to stress.These results suggest a dietary strategy to increase stress resilience.


1960 ◽  
Vol XXXIV (I) ◽  
pp. 8-18 ◽  
Author(s):  
E. Kivalo ◽  
U. K. Rinne

ABSTRACT Acute stress, chronic stress plus hydration, cortisone treatment, cortisone treatment plus dehydration were used as methods of investigation and the relation between the neurosecretory activity of the hypothalamic supraoptic nucleus and paraventricular nucleus and the neurosecretory material around the hypophysial portal vessels of the median eminence on the one hand and the corticotrophin release on the other hand, has been studied in the rat. Whereas stress stimulates both the activity of the above mentioned cells of the hypothalamus and the ACTH release, stress plus hydration causes a depression of these hypothalamic cells but nevertheless causes a marked ACTH release. Cortisone inhibits the activity of the cells in the supraoptic nucleus and the paraventricular nucleus as well as the ACTH release whereas cortisone plus dehydration causes stimulation but inhibits the ACTH release. In some stress and cortisone treatment groups the variations of the neurosecretory material around the hypophysial portal vessels and of the ACTH release were found to show a correlation. It is concluded that the activity of the cells of the supraoptic nucleus and the paraventricular nucleus and the ACTH release do not seem to have any definite connection, whereas some observations indicate that the neurosecretory material in the region of the median eminence around the hypophysial portal vessels may have some significance in ACTH release.


2021 ◽  
Vol 14 (1) ◽  
pp. e238690
Author(s):  
Takuro Endo ◽  
Taku Sugawara ◽  
Naoki Higashiyama

A 67-year-old man presented with a 2-month history of pain in his right buttock and lower limb. MRI depicted right L5/S1 lateral recess stenosis requiring surgical treatment; however, preoperative CT showed an approximately 7 cm long, thin, rod-shaped structure in the rectum, which was ultimately determined to be an accidentally ingested toothpick. It was removed surgically 6 days after diagnosis, because right leg pain worsened rapidly. The pain disappeared thereafter, and the symptoms have not recurred since. The pain might have been localised to the right buttock and posterior thigh in the early stages because the fine tip of the toothpick was positioned to the right of the anterior ramus of the S2 spinal nerve. Although sacral plexus disorder caused by a rectal foreign body is extremely rare, physicians should be mindful to avoid misdiagnosis.


Author(s):  
Elizabeth Schechter

This chapter defends the 2-agents claim, according to which the two hemispheres of a split-brain subject are associated with distinct intentional agents. The empirical basis of this claim is that, while both hemispheres are the source or site of intentions, the capacity to integrate them in practical reasoning no longer operates interhemispherically after split-brain surgery. As a result, the right hemisphere-associated agent, R, and the left hemisphere-associated agent, L, enjoy intentional autonomy from each other. Although the positive case for the 2-agents claim is grounded mainly in experimental findings, the claim is not contradicted by what we know of split-brain subjects’ ordinary behavior, that is, the way they act outside of experimental conditions.


Author(s):  
Amelie Kanovsky ◽  
Ernst J. Mueller

AbstractThe incidence of an acute compartment syndrome (ACS) of the thigh is less than 1%. It is most common in the setting of muscle overuse or muscle injury, as well as secondary to trauma, such as a femoral fracture. We present a case of an ACS in a young, healthy, and semiprofessional athlete with normal coagulation who sustained an acute stress fracture of the distal femur. After the initial fracture osteosynthesis, the patient suffered from a compartment syndrome in the right anterior aspect of the distal thigh. Following rapid surgical fasciotomy, the case was uneventful, and he returned to his preinjury sport level without any neurological consequences. This case confirms that ACS in the thigh is rare, but mainly occurs in young males with a large muscle mass due to participation in various athletic programs. We hypothesize that constant muscle over-usage primes for a larger amount of contused and protruding muscle mass in the small femoral compartment. Hence, the fatigued muscle subjects the bone to an increased mechanical force resulting in an overloading process. This ensues the accumulation of femoral microfractures and primes for the occurrence of an increased rate of stress fractures and an ACS in the thigh.


Author(s):  
Marietta Zita Poles ◽  
László Juhász ◽  
Mihály Boros

AbstractMammalian methanogenesis is regarded as an indicator of carbohydrate fermentation by anaerobic gastrointestinal flora. Once generated by microbes or released by a non-bacterial process, methane is generally considered to be biologically inactive. However, recent studies have provided evidence for methane bioactivity in various in vivo settings. The administration of methane either in gas form or solutions has been shown to have anti-inflammatory and neuroprotective effects in an array of experimental conditions, such as ischemia/reperfusion, endotoxemia and sepsis. It has also been demonstrated that exogenous methane influences the key regulatory mechanisms and cellular signalling pathways involved in oxidative and nitrosative stress responses. This review offers an insight into the latest findings on the multi-faceted organ protective activity of exogenous methane treatments with special emphasis on its versatile effects demonstrated in sepsis models.


2009 ◽  
Vol 101 (4) ◽  
pp. 1749-1754 ◽  
Author(s):  
Christopher M. Laine ◽  
Kevin M. Spitler ◽  
Clayton P. Mosher ◽  
Katalin M. Gothard

The amygdala plays a crucial role in evaluating the emotional significance of stimuli and in transforming the results of this evaluation into appropriate autonomic responses. Lesion and stimulation studies suggest involvement of the amygdala in the generation of the skin conductance response (SCR), which is an indirect measure of autonomic activity that has been associated with both emotion and attention. It is unclear if this involvement marks an emotional reaction to an external stimulus or sympathetic arousal regardless of its origin. We recorded skin conductance in parallel with single-unit activity from the right amygdala of two rhesus monkeys during a rewarded image viewing task and while the monkeys sat alone in a dimly lit room, drifting in and out of sleep. In both experimental conditions, we found similar SCR-related modulation of activity at the single-unit and neural population level. This suggests that the amygdala contributes to the production or modulation of SCRs regardless of the source of sympathetic arousal.


2021 ◽  
Vol 11 (4) ◽  
pp. 508
Author(s):  
Michael Schaefer ◽  
Julian Hellmann-Regen ◽  
Sören Enge

Stress belongs to the most frequent negative feelings people are confronted with in daily life. Strategies against acute stress include, e.g., relaxation techniques or medications, but it is also known that placebos can successfully reduce negative emotional stress. While it is widely held that placebos require deception to provoke a response, recent studies demonstrate intriguing evidence that placebos may work even without concealment (e.g., against anxiety or pain). Most of these studies are based on self-report questionnaires and do not include physiological measures. Here we report results of a study examining whether placebos without deception reduce acute stress. A total of 53 healthy individuals received either placebos without deception or no pills before participating in a laboratory stress test (Maastricht Acute Stress Test, MAST). We recorded self-report stress measures and cortisol responses before and after the MAST. Results showed no significant differences between the placebo and the control group, but when comparing participants with high relative to low beliefs in the power of placebos we found significant lower anxiety and cortisol responses for the placebo believers. These results show that non-deceptive placebos may successfully reduce acute anxiety and stress, but only in participants who had a strong belief in placebos. We discuss the results by suggesting that open-label placebos might be a possible treatment to reduce stress at least for some individuals.


1987 ◽  
Vol 177 ◽  
pp. 381-394 ◽  
Author(s):  
Dominique P. Renouard ◽  
Gabriel Chabert D'Hières ◽  
Xuizhang Zhang

The influence of rotation upon internal solitary waves is studied in a (10 m × 2 m × 0.6 m) channel located on the large rotating platform at Grenoble University. We observe an intumescence which moves along the right-hand side of the channel with respect to its direction of propagation. Along the side, once the intumescence reaches its equilibrium shape, the height variation of the interface with time is correctly described by the sech2 function, and the characteristic KdV scaling law linking the maximum amplitude and the wavelength along the side is fulfilled. The intumescence is a stable phenomenon which moves as a whole without deformation apart from the viscous damping. For identical experimental conditions, the amplitude of the intumescence along the side increases with increasing Coriolis parameter, and at a given period of rotation of the platform, the celerity along the side increases with increasing amplitude. But for identical conditions, we found that the celerity along the side is equal to the celerity that the wave would have for such conditions without rotation. The amplitude of the intumescence in a plane perpendicular to the wall decreases exponentially with increasing distance from the side, but the crest of the wave is curved backward.


2008 ◽  
Vol 68 (4) ◽  
pp. 572-578 ◽  
Author(s):  
R H Straub ◽  
G Pongratz ◽  
H Hirvonen ◽  
T Pohjolainen ◽  
M Mikkelsson ◽  
...  

Objective:Acute stress in patients with rheumatoid arthritis (RA) should stimulate a strong stress response. After cryotherapy, we expected to observe an increase of hormones of the adrenal gland and the sympathetic nervous system.Methods:A total of 55 patients with RA were recruited for whole-body cryotherapy at −110°C and −60°C, and local cold therapy between −20°C and −30°C for 7 days. We measured plasma levels of steroid hormones, neuropeptide Y (sympathetic marker), and interleukin (IL)6 daily before and after cryotherapy.Results:In both therapy groups with/without glucocorticoids (GC), hormone and IL6 levels at baseline and 5 h after cold stress did not change over 7 days of cryotherapy. In patients without GC, plasma levels of cortisol and androstenedione were highest after −110°C cold stress followed by −60°C or local cold stress. The opposite was found in patients under GC therapy, in whom, unexpectedly, −110°C cold stress elicited the smallest responses. In patients without GC, adrenal cortisol production increased relative to other adrenal steroids, and again the opposite was seen under GC therapy with a loss of cortisol and an increase of dehydroepiandrosterone. Importantly, there was no sympathetic stress response in both groups. Patients without GC and −110°C cold stress demonstrated higher plasma IL6 compared to the other treatment groups (not observed under GC), but they showed the best clinical response.Conclusions:We detected an inadequate stress response in patients with GC. It is further shown that the sympathetic stress response was inadequate in patients with/without GC. Paradoxically, plasma levels of IL6 increased under strong cold stress in patients without GC. These findings confirm dysfunctional stress axes in RA.


Sign in / Sign up

Export Citation Format

Share Document