The Insula Modulates the Effects of Aerobic Training on Cardiovascular Function and Ambulation in Multiple Sclerosis
Matteo Albergoni1, Loredana Storelli1, Paolo Preziosa2, Maria Rocca2, Massimo Filippi3
1Neuroimaging Research Unit, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 2Neuroimaging Research Unit, Division of Neuroscience, and Neurology Unit, 3Neuroimaging Research Unit, Division of Neuroscience; Neurology Unit, Neurorehabilitation Unit, and Neurophysiology Service, IRCCS San Raffaele Scientific Institute; Vita-Salute San Raffaele University
Objective:
To understand the effects of aerobic training (AT), focusing on the role of insula (differentiating in right and left) in establishing cardiovascular fitness (CF) and AT responses in people with multiple sclerosis (pwMS).
Background:
Impairment in the autonomic control of cardiovascular function is very common in pwMS. Insula is a key region related to this function with differences between left and right hemisphere. Insula lesions and atrophy are frequent in pwMS and appear to be related to cardiovascular alterations. AT targets the cardiopulmonary system and is proposed as a neuroprotective strategy in several neurological conditions.
Design/Methods:
Sixty-one pwMS were randomized in two groups (MS-AT and MS-C) to perform 24 training sessions of 30-40 minutes for 2-3 times per week. MS-AT performed moderate AT, while MS-C underwent non-specific motor training. All patients had a baseline and follow-up evaluation after the training period, including assessment of maximal peak of oxygen consumption (VO2max), heart rate reserve (HRR), 6-minute walk test (6MWT) and a MRI scan to quantify lesion volumes (LV), global and regional brain atrophy. Two age- and sex-matched healthy control (HC) groups were enrolled for baseline comparison of CF and brain volumetry data.
Results:
At baseline, MS patients showed impaired values of VO2max, HRR and 6MWT (p<0.001) and a widespread pattern of atrophy compared to HC, including bilateral insula. In MS, higher left insula LV correlated to higher HRR (R=0.27, p<0.05). After training, MS-AT experienced an improvement in 6MWT compared to MS-C and this enhancement was greater in patients without insular lesions. At follow-up, MS-C showed a reduction of left anterior insula volume compared to baseline (p<0.001).
Conclusions:
In pwMS, AT improves CF and walking capacity. It showed a neuroprotective effect, especially for the left insula that has a stronger relationship with CF, compared to the contralateral region.