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Abstract
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Obesity is associated with increased blood concentrations of the anorexigenic hormone leptin; however, obese individuals are resistant to its anorexigenic effects. Obesity also promotes matrix metalloproteinases activation in the hypothalamus, which cleaves the leptin receptor’s extracellular domain and impaired leptin-mediated signaling. However, very little is known whether aerobic exercise training has an anti-blood brain barrier (BBB) destructive effect induced by high fat diet in adolescents’ brain, or not. Therefore, we focused on the effect of aerobic training on cerebral expression of BBB-destructing matrix-metalloproteinase 9 (MMP9) and obesity-related leptin receptor (OB-R) in adolescent rats exposed to a high-fat diet.
28 male Wistar rats (age: 35 days) were randomly divided into four groups: (a) chow diet (CD), (b) CD with exercise training (ExT), high-fat diet (HD), and (c) HD with ExT. The high-fat diet was consumed between the 35th and 100th days of life. The training was included on four weeks of treadmill running, three sessions/week, 40 min/session, at 55-65% of the VO2max. initiated from the 70th day of life. Homogenous brain tissue MMP9 and OB-R levels were measured by Western blot method.
HD significantly increased MMP9 and decreased OB-R in HD animals compared, and these changes were attenuated in HD-ExT group (P<0.05)
Aerobic exercise training protects the adolescent’s’ brain against destructive effects induced by a high-fat diet, which is thought to be partially mediated by the downregulation of MMP9 and upregulation of the leptin receptor. However, more research remains to be done in this area because of the lack of similar evidence and also some of the limitations in this study.
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