Essential oils (EOs) are extracted from plants and contain active components with therapeutic effects. Evidence shows that various types of EOs have a wide range of health benefits. In our previous studies, the potential of lavender EO for prevention and even treatment of depression and anxiety symptoms was demonstrated. The favourable outcomes may be due to multiple mechanisms, including the regulation of monoamine level, the induction of neurotrophic factor expression, the regulation of the endocrine system and the promotion of neurogenesis. The molecules of EOs may reach the brain and exert an effect through two distinctive pathways, namely, the olfactory system and the respiratory system. After inhalation, the molecules of the EOs would either act directly on the olfactory mucosa or pass into the respiratory tract. These two delivery pathways suggest different underlying mechanisms of action. Different sets of responses would be triggered, such as increased neurogenesis, regulation of hormonal levels, activation of different brain regions, and alteration in blood biochemistry, which would ultimately affect both mood and emotion. In this review, we will discuss the clinical effects of EOs on mood regulation and emotional disturbances as well as the cellular and molecular mechanisms of action. Emphasis will be put on the interaction between the respiratory and central nervous system and the involved potential mechanisms. Further evidence is needed to support the use of EOs in the clinical treatment of mood disturbances. Exploration of the underlying mechanisms may provide insight into the future therapeutic use of EO components treatment of psychiatric and physical symptoms.
4 January 2017 in Evidence-Based Complementary and Alternative Medicine
Background. Depression is one of the greatest health concerns affecting 350 million people globally. Aromatherapy is a popular CAM intervention chosen by people with depression. Due to the growing popularity of aromatherapy for alleviating depressive symptoms, in‐depth evaluation of the evidence‐based clinical efficacy of aromatherapy is urgently needed. Purpose. This systematic review aims to provide an analysis of the clinical evidence on the efficacy of aromatherapy for depressive symptoms on any type of patients. Methods. A systematic database search was carried out using predefined search terms in 5 databases: AMED, CINHAL, CCRCT, MEDLINE, and PsycINFO. Outcome measures included scales measuring depressive symptoms levels. Results. Twelve randomized controlled trials were included and two administration methods for the aromatherapy intervention including inhaled aromatherapy (5 studies) and massage aromatherapy (7 studies) were identified. Seven studies showed improvement in depressive symptoms. Limitations. The quality of half of the studies included is low, and the administration protocols among the studies varied considerably. Different assessment tools were also employed among the studies. Conclusions. Aromatherapy showed potential to be used as an effective therapeutic option for the relief of depressive symptoms in a wide variety of subjects. Particularly, aromatherapy massage showed to have more beneficial effects than inhalation aromatherapy.
7 June 2016 in Cochrane Database of Systematic Reviews
Purpose: This study translated and validated the Kujala scale, a well-documented questionnaire for patients with patellofemoral pain, into Chinese version. Method: Chinese Kujala scale was translated from the original English version following the recommendations of the International Society for Pharmacoeconomics and Outcomes Research. Sixty four Chinese reading patients who are diagnosed of patellofemoral pain were recruited from multiple hospitals and physiotherapy clinics. Psychometric property was evaluated in terms of test-retest reliability and internal consistency. Convergent validity was examined by Spearman rank correlation coefficient tests by comparing its score with the validated Chinese version of WOMAC Osteoarthritis Index and SF-36. Results: Chinese Kujala scale demonstrated excellent reliability (ICC = 0.968, p < 0.001). Cronbach’s α of individual questions and its overall value were above 0.7. Strong correlation was found between the Chinese Kujala scale and the WOMAC Osteoarthritis Index (rho = −0.708, p < 0.001). Fairly weak correlations were also found between Chinese Kujala scale with the “physical” (rho = 0.413–0.498, p < 0.001) and “energy vitality” (rho = 0.290, p = 0.02) domains of SF-36. However, the relationship between the “bodily pain” was not significant (rho = 0.136, p = 0.284). Conclusion: The Chinese translated version of Kujala scale is a reliable and valid instrument for assessing the patellofemoral pain associated functional disturbances among the patient cohort.
Neurogenesis is the process by which functional new neurons are generated from the neural stem cells (NSCs) or neural progenitor cells (NPCs). Increasing lines of evidence show that neurogenesis impairment is involved in different neurological illnesses, including mood disorders, neurogenerative diseases, and central nervous system (CNS) injuries. Since reversing neurogenesis impairment was found to improve neurological outcomes in the pathological conditions, it is speculated that modulating neurogenesis is a potential therapeutic strategy for neurological diseases. Among different modulators of neurogenesis, melatonin is a particularly interesting one. In traditional understanding, melatonin controls the circadian rhythm and sleep–wake cycle, although it is not directly involved in the proliferation and survival of neurons. In the last decade, it was reported that melatonin plays an important role in the regulation of neurogenesis, and thus it may be a potential treatment for neurogenesis-related disorders. The present review aims to summarize and discuss the recent findings regarding the protective effects of melatonin on the neurogenesis impairment in different neurological conditions. We also address the molecular mechanisms involved in the actions of melatonin in neurogenesis modulation.