Search bioRxiv⌕ Search

Biology subjects

Vetter, P. E.

Publications and source records attributed to Vetter, P. E..

2 recordsLinked to original sources

American ginseng (Panax quinquefolius L.) extracts (G1899) reverse stress-induced behavioral abnormalities in mice

Stress affects brain functions, which leads to the development of mental disorders like anxiety, depression, cognitive decline, and social dysfunction. There is increasing focus on the role of nutritional, herbal and nutraceutical compounds on mental and cognitive functioning. Interestingly, studies suggest that American ginseng (Panax quinquefolius L.) extracts (G1899) improve cognition. We thus examined whether G1899 showed protective effects on stress-induced behavioral changes in animals. 200 mg/kg G1899 was orally administered daily for 4 weeks to 2-3-month-old female and male mice before inducing stress. To induce acute stress in animals, we intraperitoneally injected a low dose of lipopolysaccharides (LPS) (10 g/kg), and saline was used as a control. We also used chronic restraint stress (CRS) as a chronic stress model in mice. After LPS injection or CRS, multiple behavioral assays were carried out - a sucrose preference test, an open filed test, reciprocal social interaction, contextual fear conditioning, and a tail suspension test - to determine whether acute or chronic stress affected animals behaviors and whether G1899 had protective effects against stress-induced behavioral dysfunction. We found that both LPS injection and CRS induced stress-related behavioral dysfunction, including depression-like behavior, anhedonia, social dysfunction, and fear memory impairments in both females and males. However, G1899 treatment was sufficient to reverse stress-induced behavioral abnormalities in animals. Our data further suggested that G1899 reduced the activity of hippocampal neurons by suppressing glutamatergic activity. Our study suggests that G1899 supplements can be protective against both acute and chronic stress in mice by suppressing neuronal and synaptic activity. HighlightsO_LIAmerican ginseng (Panax quinquefolius L.) extract (G1899) treatment reverses acute stress-induced behavioral dysfunction in mice. C_LIO_LIG1899 treatment reverses chronic stress-induced behavioral dysfunction in mice. C_LIO_LIG1899 treatment reduces serum corticosterone levels in chronically stressed mice. C_LIO_LIG1899 treatment suppresses glutamatergic activity in hippocampal neurons. C_LI

neuroscience↗

Ketamine reverses chronic stress-induced behavioral changes via the expression of Ca2+-permeable AMPA receptors in mice

Background and Purpose: Chronic stress affects brain functions leading to the development of mental disorders like anxiety and depression, as well as cognitive decline and social dysfunction. Among many biological changes in chronically stressed brains, disruptions in AMPA Receptor (AMPAR)-mediated synaptic transmission in the hippocampus are associated with stress responses. We have revealed that low-dose ketamine rapidly induces the expression of GluA1-containing, GluA2-lacking Ca2+-Permeable AMPARs (CP-AMPARs), which enhances glutamatergic synaptic strength in hippocampal neurons. Additionally, subanesthetic low-dose ketamine decreases anxiety- and depression-like behaviors in naive animals. In addition to reducing depression, some research indicates that ketamine may have protective effects against chronic stress in both humans and animals. However, the role of CP-AMPARs in the actions of ketamine's antistress effects is largely unknown. Experimental Approach: We use whole-cell patch-clamp recordings from CA1 pyramidal neurons in female and male hippocampal slices and multiple behavioral assays including reciprocal social interaction, contextual fear conditioning, and tail suspension test. Key Results: We demonstrate that low-dose ketamine treatment reverses chronic restraint stress (CRS)-induced social dysfunction, hippocampus-dependent fear memory loss, and depression-like behavior in both female and male mice. Furthermore, we show that the ketamine-induced antistress effects on these behaviors are dependent on CP-AMPARs. Conclusion and Implications: Our findings suggest that subanesthetic low-dose ketamine rapidly triggers synaptic insertion of CP-AMPARs in the hippocampus, which induces antidepressant and antistress effects.

neuroscience↗