Housing In An Enriched Environment Enhances The Neuroprotective Effect Of Celastrus Paniculatus And Tribulus Terrestris In An Animal Model Of Chronic Stress

Abstract

Introduction: Prolonged exposure to stress can contribute to depressive episodes. Preclinical studies have shown that stimuli like environmental enrichment (EE) can produce beneficial effects against stress by positively modulating neuroplasticity, neurochemistry, and behaviour. Hence, we explored whether exposure to EE can augment the neuroprotective activities of Celastrus paniculatus (CP) and Tribulus terrestris (TT) in stressed conditions. Materials and Methods: Rats were placed in immobilisation bags and stressed for two hours a day for ten days. After that, these stressed rats were treated by CP or TT, alone or in combination with enriched housing. Behavioural analysis in elevated plus maze, open field, forced swim and sucrose preference tests. The novel object recognition test and the rewarded alteration test on the T-maze were used to assess working memory. The brain-derived neurotrophic factor, interleukin-6, and tumour necrotic factor-alpha were measured in the hippocampus and prefrontal cortical tissues following stress and herbal treatment combined with an enriched environment. Results: We found that Celastrus paniculatus and Tribulus terrestris, combined with an enriched environment, produced a synergistic neuroprotective effect. CP + EE and TT + EE improved working memory and recognition memory in CIS animals, but they also reduced anxiety and depressive-like behaviours. TNF-α and IL-6 levels were decreased while brain-derived neurotrophic factor levels were raised in the frontal cortex and hippocampus regions, respectively. Conclusion: Our results show that living in an enriched environment can improve CP and TT neuromodulatory activities, highlighting the potential of combining sensory-motor interventions with herbal remedies for psychiatric disorders.