Abstract
AimsObesity is known to be associated with an altered thermoregulation as well as a dysregulation of sympathetic nervous system (SNS). Considering the ability of deep transcranial magnetic stimulation (dTMS) to modulate the SNS, we hypothesized a potential role of dTMS in affecting thermoregulation in obesity. Aims of the study were to monitor the effect of a single session of dTMS on body temperature in subjects with obesity, and to correlate the dTMS-induced changes in body temperature with activation of the SNS (epinephrine and norepinephrine release).MethodsTwenty-nine subjects with obesity [5 M, 24 F; age 50 (IQR: 58, 38) yrs; BMI 36.1 (IQR: 33.9, 38.7) kg/m2] were randomized into 2 groups receiving a single session of high frequency stimulation (HF) or sham stimulation. Under neutral thermal conditions, infrared thermography was utilized to assess bilateral fingernail-beds and abdominal temperature.ResultsDuring a single session HF, the average temperature of both fingernail-beds decreased. Right-hand temperature difference was statistically greater in HF vs Sham: median = – 1.45 (IQR: – 2.0, – 1.0) °C for HF, p = 0.009. While temperature variation in the fingernail-bed of left hand was not statistically significant in HF compared to Sham: median = – 1.26 (IQR: – 1.6, –0.5) °C, p = 0.064. Concurrently, when estimating the effect of norepinephrine variation on temperature change of fingernail-bed of left hand, a borderline significant positive association was estimated (beta = 1.09, p = 0.067) in HF.ConclusionsDeep TMS revealed to be effective in modulating temperature in subjects with obesity, partially reversing obesity-induced alterations in heat production and dissipation with a potential SNS-mediated mechanism.
Highlights
Obesity is known to be associated with an altered thermoregulation [1, 2]
No significant differences in gender, age, body weight and body mass index (BMI) were found between the two arms (Table 2)
We examined the effects on body temperature of a single treatment session with deep transcranial magnetic stimulation (dTMS) over the prefrontal cortex (PFC) and the insula, bilaterally, using either high frequency stimulation (HF) or sham stimulation in individuals with obesity
Summary
Obesity is known to be associated with an altered thermoregulation [1, 2]. An increased resting metabolic caloric production [3, 4], combined with reduced heat dissipation due to the subcutaneous adipose tissue that acts as an insulating layer, has been shown in individuals with obesity [5]. Heat retention in areas of the body with greater adiposity is counteracted by an augmented heat release from the extremities, as the fingernail-beds of both hands to maintain euthermia in subject with obesity [5, 6]. The hypothalamus, the preoptic anterior hypothalamus, represents the coordinating or central integration center for the thermoregulation [7]. It receives inputs from peripheral as well as from central thermoreceptors, which could be cold or warmth-responding [8]. Two branches of the sympathetic nervous system (SNS) are mainly effectors of skin blood flow [10]: sympathetic vasoconstrictor nerves, which release norepinephrine (NE) and co-transmitters and are responsible for minor variations in skin blood flow occurring during most daily activities, and the sympathetic active vasodilator system that works via cholinergic nerve co-transmission, but in this case, the underlying mechanisms are incompletely understood [11]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
