**Minsang Kim 1, Minah Song 2, Hee-Jin Oh 2, Jin Hui 3, Woori Bae 2, Jihwan Shin 2, Sang-Dock Ji 4, Young Ho Koh 5,6, Joo Won Suh 3, Hyunwoo Park 7,\* and Sungho Maeng 2,\***


Received: 14 October 2019; Accepted: 8 November 2019; Published: 30 December 2019

**Abstract:** (1) Background: By 2050, it is estimated that 130 million people will be diagnosed with dementia, and currently approved medicines only slow the progression. So preventive intervention is important to treat dementia. Mild cognitive impairment is a condition characterized by some deterioration in cognitive function and increased risk of progressing to dementia. Therefore, the treatment of mild cognitive impairment (MCI) is a possible way to prevent dementia. *Angelica gigas* reduces neuroinflammation, improves circulation, and inhibits cholinesterase, which can be effective in the prevention of Alzheimer's disease and vascular dementia and the progression of mild cognitive impairment. (2) Methods: *Angelica gigas* (AG) extract 1 mg/kg was administered to mildly cognitive impaired mice, models based on mild traumatic brain injury and chronic mild stress. Then, spatial, working, and object recognition and fear memory were measured. (3) Result: *Angelica gigas* improved spatial learning, working memory, and suppressed fear memory in the mild traumatic brain injury model. It also improved spatial learning and suppressed cued fear memory in the chronic mild stress model animals. (4) Conclusions: *Angelica gigas* can improve cognitive symptoms in mild cognitive impairment model mice.

**Keywords:** *Angelica gigas*; mild cognitive impairment; traumatic brain injury; chronic mild stress
