Resistance training and Urtica dioica increase neurotrophin levels and improve cognitive function by increasing age in the hippocampus of rats

Introduction: Inflammation and oxidative stress are two major factors in accelerating brain aging. Consumption of some traditional herbs with antioxidant and anti-inflammatory properties such as Urtica dioica extract (Ud) and resistance training (RT) may be effective in controlling premature aging and memory impairment. Therefore, we hypothesized that the combined effect of RT and Ud might play an essential role in preventing memory disorders and hippocampal tissue changes caused by increasing age in rats. Methods: 28 male Wistar rats (24-week) were divided into 4-groups (n = 7): control (C), Ud, RT, and Ud+RT. RT groups were trained for five weeks, and Ud extract in the 0.0166 w/v concentration (50 mg/kg, oral/daily) was administered. We also examined the effects of RT and Ud on the behavioral (memory and learning), histological (the morphological changes in the dentate gyrus), and transcript aspects of hippocampal tissue. Results: Aging led to karyopyknosis in the hippocampal tissue, which was alleviated by RT and Ud supplemen-tation. RT and Ud were accompanied by increased GPx, GSH, GAP-43, and decreased CAP-1 levels in the hip-pocampus. Moreover, RT and Ud led to increased NGF, BDNF, and GAP-43 levels, decreased MDA, and protection of hippocampal tissue from karyopyknosis, which was associated with cognitive improvement. However, these interventions had no significant effect on the hippocampal levels of IL-1 beta, SOD, and CAT. Conclusions: These findings suggest that increasing age decreases hippocampal NGF, BDNF, and GAP-43 levels and impairs cognition, which may be reversed by regular RT and Ud extract.

Automated summary

In this study, the combined effect of resistance training (RT) and Urtica dioica extract (Ud) was investigated in preventing memory disorders and hippocampal tissue changes caused by aging in rats. The results showed that RT and Ud supplementation alleviated karyopyknosis in hippocampal tissue and improved cognitive function. These interventions also increased the levels of antioxidant enzymes and neurotrophic factors in the hippocampus, while protecting against oxidative stress and hippocampal damage.