Lab Anim Res.  2022 Sep;38(3):159-168. 10.1186/s42826-022-00134-3.

Humulus japonicus attenuates LPS-and scopolamine-induced cognitive impairment in mice

• Go J
• Park HY
• Lee DW
• Maeng SY
• Lee IB
• Seo YJ
• An JP
• Oh WK
• Lee CH
• Kim KS

• KMID: 2534143
• DOI: http://doi.org/10.1186/s42826-022-00134-3

Abstract

Background
Neuroinflammation plays an important role in cognitive decline and memory impairment in neurodegenerative disorders. Previously, we demonstrated that Humulus japonicus (HJ) has anti-inflammatory effects in rodent models of Alzheimer’s disease and Parkinson’s disease. The present study aimed to examine the protective potential of HJ extracts against lipopolysaccharide (LPS)-induced cognitive impairment and scopolamine-induced amnesia in mouse models. Cognitive improvement of mice was investigated by novel object recognition test. For analyzing effects on neuroinflammation, immunohistochemistry and quantitative real-time polymerase chain reaction (qRTPCR) assays were performed.
Results
We found that the oral administration of HJ significantly improved cognitive dysfunction induced by LPS in a novel object recognition test. The LPS-induced activation of microglia was notably decreased by HJ treatment in the cortex and hippocampus. HJ administration with LPS also significantly increased the mRNA expression of interleukin (IL)-10 and decreased the mRNA expression of IL-12 in the parietal cortex of mice. The increased expression of LPS-induced complement C1q B chain (C1bq) and triggering receptor expressed on myeloid cells 2 (Trem2) genes was significantly suppressed by HJ treatment. In addition, HJ administration significantly improved novel object recognition in a scopolamine-induced amnesia mouse model.
Conclusions
These findings revealed that HJ has a beneficial effect on cognitive impairment and neuroinflammation induced by systemic inflammation and on amnesia induced by scopolamine in mice.

Keyword

Humulus japonicus; Cognitive function; Neuroinflammation; Mouse model