Qing-Shan Liu1, Hai-Lun Jiang2, Yu Wang2, Lin-Lin Wang2, Jun-Xia Zhang2, Cheng-Hui He3, Shuai Shao2, Tian-Tai Zhang2, Jian-Guo Xing4, Rui Liu5. 1. Key Laboratory of Ministry of Education, College of Pharmacy, Minzu University of China, Beijing, 100081, PR China. 2. Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, PR China. 3. Key Laboratory of Uighur Medicine of Xinjiang Uygur Autonomous Region, Xinjiang, Institute of Materia Medica, Urumqi 830004, PR China. 4. Key Laboratory of Uighur Medicine of Xinjiang Uygur Autonomous Region, Xinjiang, Institute of Materia Medica, Urumqi 830004, PR China. Electronic address: xjguodd@163.com. 5. Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, PR China; Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, PR China. Electronic address: neuropharmacol_zl@163.com.
Abstract
AIMS: Alzheimer's disease (AD) is an incurable neurodegenerative disorder characterized by global cognitive impairment that involves accumulation of amyloid-beta peptides (Aβ) in the brain. Herbal approaches can be used as alternative medicines to slow the progression of AD. This study aimed to determine the beneficial effects and potential underlying mechanisms of total flavonoid extract from Dracoephalum moldavica L. (TFDM) for attenuating Alzheimer-related deficits induced by Aβ. MAIN METHODS: We used amyloid precursor protein (APP) and presenilin 1 (PS1) double transgenic mice and copper-injured APP Swedish mutation overexpressing SH-SY5Y cells to evaluate the beneficial effects of TFDM. Further, identifying the mechanisms of action was conducted on anti-amyloidogenic and neurotrophic transductions. KEY FINDINGS: Our results indicated that TFDM treatment ameliorated cognitive impairments and neurodegeneration and improved the antioxidant defense system in APP/PS1 mice. TFDM also reduced Aβ burden by relieving Aβ deposition, decreasing insoluble Aβ levels, and inhibiting β-amyloidogenic processing pathway involving downregulation of β-secretase and β-C-terminal fragment in the brain. In the in vitro model of AD, TFDM treatment protected injured cells, and combined with the beneficial effects of decreasing APP levels, lowered Aβ1-42 and regulated the redox imbalance. Moreover, TFDM preserved the extracellular signal-regulated kinase/cAMP response element-binding protein/brain-derived neurotrophic factor pathway both in vitro and in vivo. SIGNIFICANCE: In conclusion, TFDM clearly demonstrated neuroprotective effects by restoring the anti-amyloidogenic and neurotrophic transductions in the context of AD-associated deficits. These findings indicate the potential use of herb-based substances as supplements or potential alternative supplements for attenuating the progression of AD.
AIMS: Alzheimer's disease (AD) is an incurable neurodegenerative disorder characterized by global cognitive impairment that involves accumulation of amyloid-beta peptides (Aβ) in the brain. Herbal approaches can be used as alternative medicines to slow the progression of AD. This study aimed to determine the beneficial effects and potential underlying mechanisms of total flavonoid extract from Dracoephalum moldavica L. (TFDM) for attenuating Alzheimer-related deficits induced by Aβ. MAIN METHODS: We used amyloid precursor protein (APP) and presenilin 1 (PS1) double transgenic mice and copper-injured APP Swedish mutation overexpressing SH-SY5Y cells to evaluate the beneficial effects of TFDM. Further, identifying the mechanisms of action was conducted on anti-amyloidogenic and neurotrophic transductions. KEY FINDINGS: Our results indicated that TFDM treatment ameliorated cognitive impairments and neurodegeneration and improved the antioxidant defense system in APP/PS1mice. TFDM also reduced Aβ burden by relieving Aβ deposition, decreasing insoluble Aβ levels, and inhibiting β-amyloidogenic processing pathway involving downregulation of β-secretase and β-C-terminal fragment in the brain. In the in vitro model of AD, TFDM treatment protected injured cells, and combined with the beneficial effects of decreasing APP levels, lowered Aβ1-42 and regulated the redox imbalance. Moreover, TFDM preserved the extracellular signal-regulated kinase/cAMP response element-binding protein/brain-derived neurotrophic factor pathway both in vitro and in vivo. SIGNIFICANCE: In conclusion, TFDM clearly demonstrated neuroprotective effects by restoring the anti-amyloidogenic and neurotrophic transductions in the context of AD-associated deficits. These findings indicate the potential use of herb-based substances as supplements or potential alternative supplements for attenuating the progression of AD.