Elevated biomarkers of inflammation are commonly observed in individuals who have depression (Dinan, 2009). Chronic activation of the body's inflammatory response system promotes the development of depressive symptoms and induces changes in brain and neuroendocrine function, suggesting that strategies that induce anti-inflammatory pathways may reduce symptoms of depression. Preclinical studies have found that exogenous administration of the anti-inflammatory cytokine IL-10 can improve depressive symptoms (Roque et al., 2009; Worthen et al., 2020).
Sauna use has been shown to reduce symptoms of depression. In a randomized controlled trial involving 28 individuals diagnosed with mild depression, participants who received 4 weeks of sauna sessions experienced reduced symptoms of depression, such as improved appetite and reduced somatic complaints and anxiety, compared to the control group, which received bedrest instead of sauna therapy (Masuda et al., 2005). In a randomized, double-blind study of 30 healthy adults diagnosed with depression, participants who were exposed to a single session of whole-body hyperthermia in which core body temperature was elevated to 38.5 °C (101.3 °F) experienced an acute antidepressant effect that was apparent within 1 week of treatment and persisted for 6 weeks after treatment (Janssen et al., 2016). Some of these benefits on mood may be due to the effects of heat stress on acutely increasing plasma levels of pro-inflammatory IL-6 and anti-inflammatory IL-10, similar to effects observed following exercise (Miller and Raison, 2016; Windsor et al., 2018; Zychowska et al., 2018). Interestingly, a small study in which individuals diagnosed with major depressive disorder received whole-body hyperthermia demonstrated that the participants' antidepressant response correlated with reductions in core body temperature in the 5 days post treatment (Hanusch et al., 2013).
Beta-endorphins are endogenous opioids that are produced and stored primarily in the anterior pituitary gland of the brain. They play important roles in pain management and reward circuitry. Evidence suggests that beta-endorphins are responsible in part for the euphoric or pleasant sensations that commonly occur in response to exercise (Basso and Suzuki, 2017). The binding of beta-endorphins to mu-opioid receptors on nerve cells suppresses the release of pain-promoting substances in the brain. Sauna use promotes robust increases in beta-endorphins (Jezova et al., 1985; Kukkonen-Harjula and Kauppinen, 1988; Vescovi et al., 1992).
Dynorphin is an opioid that is generally responsible for the sensation of dysphoria, a profound sense of unease or dissatisfaction. Dynorphin may also help mediate the body's response to heat, helping the body to cool (Xin et al., 1997). Heat activates neurons in the dorsal lateral parabrachial nucleus that express dynorphin (Tan and Knight, 2018). The activation of this thermosensory pathway elicits heat-defense responses in which the binding of dynorphin to kappa-opioid receptors triggers cellular events that promote pain and distress (Nakamura and Morrison, 2010). The heat stress caused by sauna use may promote dynorphin release, which may be responsible for the general sense of discomfort experienced during heat exposure. Interestingly, in a biological feedback response that occurs after dynorphin binds to the kappa-opioid receptor, mu-opioid receptors become more sensitized to beta-endorphins (Narita et al., 2003). Thus, repeated sauna use may sensitize mu-opioid receptors to endorphins.
Club Recharge - 14490 Pearl Road - Strongsville - OH 44136.
Hours: Monday-Friday 10AM-7PM - Saturday 10AM-3PM
(Phone: 440-567-1146)
コメント