TNF and major depressive disorder: Recently, it has been shown how mindfulness-based cognitive therapy can reduce symptoms of depression, anxiety and sleep disturbances, linking these improvements to a decrease in inflammatory markers such as IL-1β, IL-6, IL-8, TNF-α and increased BDNF.85 These results suggest a link between psychotherapeutic interventions and biological changes, opening prospects for reverse treatments, such as anti-inflammatory ones, to improve symptoms.