January 28, 2022 - Texas Tech University launched a pre/post pilot study, participated by multiple departments within the institution, to investigate neurobiological mechanisms and plasma metabolites in an 8-week Tai Chi group intervention in postmenopausal women with knee osteoarthritis.
Twelve postmenopausal women underwent Tai Chi group exercise for 8 weeks (60 min/session, three times/week). Outcomes were measured before and after Tai Chi intervention including pain intensity (VAS), Brief Pain Inventory (BPI), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), plasma metabolites, as well as resting-state functional magnetic resonance imaging (rs-fMRI, 10 min, eyes open), diffusion tensor imaging (DTI, 12 min), and structural MRI (4.5 min) in a subgroup.
Significant pre/post changes were observed with reduced knee pain and stiffness, that likely contributed to improved physical function with Tai Chi. Moderate to large effect sizes pre/post increase in rs-fMRI connectivity were observed between bilateral mPFC and the amygdala seed regions. Increased DTI connectivity was observed between bilateral mPFC and left amygdala. Significantly higher levels of lysophosphatidylcholines were observed after Tai Chi but lower levels of some essential amino acids. Amino acid levels were lower after 8 weeks of Tai Chi and many of the lipid metabolites were higher after Tai Chi. Further, plasma non-HDL cholesterol levels were lower after Tai Chi.
This pilot study showed moderate to large effect sizes, suggesting an important role that cortico-amygdala interactions related to Tai Chi have on pain and physical function in subjects with knee osteoarthritis pain. Metabolite analyses revealed a metabolic shift of higher lyso-lipids and lower amino acids that might suggest greater fatty acid catabolism, protein turnover and changes in lipid redistribution in response to Tai Chi exercise. The results also support therapeutic strategies aimed at strengthening functional and structural connectivity between the mPFC and the amygdala. Controlled clinical trials are warranted to confirm these observed preliminary effects.