Effects and Mechanism of Huannao Yicong Decoction Extract on the Ethology of Transgenic APP/PS1 Mice

Rhizoma Coptidis for Alzheimer's Disease and Vascular Dementia: A Literature Review

BACKGROUND

Alzheimer's disease (AD) and vascular dementia (VaD) are major types of dementia, both of which cause heavy economic burdens for families and society. However, no currently available medicines can control dementia progression. Rhizoma coptidis, a Chinese herbal medicine, has been used for >2000 years and is now gaining attention as a potential treatment for AD and VaD.

METHODS

We reviewed the mechanisms of the active ingredients of Rhizoma coptidis and Rhizoma coptidis-containing Chinese herbal compounds in the treatment of AD and VaD. We focused on studies on ameliorating the risk factors and the pathological changes of these diseases.

RESULTS

The Rhizoma coptidis active ingredients include berberine, palmatine, coptisine, epiberberine, jatrorrhizine and protopine. The most widely studied ingredient is berberine, which has extensive therapeutic effects on the risk factors and pathogenesis of dementia. It can control blood glucose and lipid levels, regulate blood pressure, ameliorate atherosclerosis, inhibit cholinesterase activity, Aβ generation, and tau hyperphosphorylation, decrease neuroinflammation and oxidative stress and alleviate cognitive impairment. Other ingredients (such as jatrorrhizine, coptisine, epiberberine and palmatine) also regulate blood lipids and blood pressure; however, there are relatively few studies on them. Rhizoma coptidis-containing Chinese herbal compounds like Huanglian-Jie-Du-Tang, Huanglian Wendan Decoction, Banxia Xiexin Decoction and Huannao Yicong Formula have anti-inflammatory and antioxidant stress activities, regulate insulin signaling, inhibit γ-secretase activity, neuronal apoptosis, tau hyperphosphorylation, and Aβ deposition, and promote neural stem cell differentiation, thereby improving cognitive function.

CONCLUSION

The "One-Molecule, One-Target" paradigm has suffered heavy setbacks, but a "multitarget- directed ligands" strategy may be viable. Rhizoma coptidis active ingredients and Rhizoma coptidiscontaining Chinese herbal compounds have multi-aspect therapeutic effects on AD and VaD.

Roflumilast ameliorates cognitive impairment in APP/PS1 mice via cAMP/CREB/BDNF signaling and anti-neuroinflammatory effects

Phosphodiesterase type 4 (PDE4) inhibitors can prevent the breakdown of the second messenger cyclic adenosine monophosphate (cAMP) and improve cognitive performances in several animal models of cognition. However, the clinical development of PDE4 inhibitors has been seriously hampered by severe side effects, such as vomiting and nausea. In this study, we investigated the effect and mechanism of roflumilast, an FDA-approved PDE4 inhibitor for treatment of chronic obstructive pulmonary disease (COPD), on learning and memory abilities in the APP/PS1 mouse model of Alzheimer's disease (AD). APP/PS1 transgenic mice received 3 intragastric doses of roflumilast (0.1, 0.2 and 0.4 mg/kg) daily for 3 weeks followed by behavioral tests. Chronic administration of roflumilast significantly improved the learning and memory abilities of APP/PS1 transgenic mice in the novel object recognition task, Morris water maze, and the step-down passive avoidance task. In addition, roflumilast increased the cAMP, phosphorylated cAMP response-element binding protein (p-CREB) and brain-derived neurotrophic factor (BDNF) levels, and reduced the nuclear translocation of nuclear factor-kappa B (NF-κB) p65, and proinflammatory cytokine (IL-6, TNF-a and IL-1β) levels in the hippocampus of APP/PS1 transgenic mice. In conclusion, these findings suggest that roflumilast can enhance cognitive function in APP/PS1 transgenic mice, which may be related to its stimulation of the cAMP/CREB/BDNF pathway and anti-neuroinflammatory effects.

Effect and Safety of Huannao Yicong Formula () in Patients with Mild-to-Moderate Alzheimer's Disease: A Randomized, Double-Blinded, Donepezil-Controlled Trial

OBJECTIVE

To assess the effect and safety of Huannao Yicong Formula (, HYF) in the treatment of patients with mild-to-moderate Alzheimer's disease (AD).

METHODS

Sixty patients with mild-tomoderate AD were evenly randomized into HYF group and donepezil group with the random number method. Patients in the HYF group took 5 g of HYF granules twice daily and 5 mg placebo of donepezil once daily. Patients in the donepezil group took 5 mg donepezil once daily and 5 g placebo of HYF granules twice daily. The intervention lasted for 6 months. Clinical researchers, participants and statisticians were blinded to the treatment assignment throughout the study. The primary outcomes were scores of Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog) and Chinese Medicine Symptom Scale (CM-SS). The secondary outcomes were scores of Montreal Cognitive Assessment (MoCA) test and Mini-Mental State Exam (MMSE). The serum levels of acetylcholinesterase (AchE) and amyloid-β protein 42 (Aβ₄₂) were detected with enzymelinked immunosorbent assay kits. The scale assessments were conducted at baseline, the 3rd and 6th months of treatment, respectively. Biochemistry tests were conducted at baseline and the 6th month of treatment.

RESULTS

A total of 52 patients completed the trial, 28 in HYF group and 24 in donepezil group. Compared with the baseline, HYF and donepezil signifificantly decreased the total scores of ADAS-Cog and CM-SS, and signifificantly increased the scores of MoCA and MMSE after 6-month treatment (all P<0.01). Both treatments remarkably reduced the serum levels of AchE and Aβ₄₂ (both P<0.05). The CM-SS total effective rate of HYF was signifificantly higher than donepezil [75.00% (21/28) vs. 54.17% (13/24), P<0.05]. No severe adverse events were observed in both groups.

CONCLUSION

HYF is effective and safe for improving the cognitive function in mildto-moderate AD patients. [Trial registration: Chinese Clinical Trial Registry (Reg No. ChiCTR-IOR-17011746)].

The Chinese herbal formula Fuzheng Quxie Decoction attenuates cognitive impairment and protects cerebrovascular function in SAMP8 mice

PURPOSE

This study was designed to explore the underlying mechanism of action for a Fuzheng Quxie Decoction (FQD) in Alzheimer's disease (AD), to validate its neuroprotective effects, and to provide experimental support for its predicted mechanism of action.

METHODS

An integrative approach to network pharmacology was performed to predict the mechanism of action for treatment of AD with FQD. The predicted mechanism was validated in SAMP8 mice.

RESULTS

With predicted putative FQD targets and a collection of AD-related genes, 245 possible regulatory targets of FQD were identified for the treatment of AD. Pathway-enrichment analysis for the possible regulatory targets indicated that vascular endothelial growth factor (VEGF) and VEGF-receptor signaling were pivotal in the treatment of AD with FQD. In vivo experiments confirmed the neuroprotective effect and the predicted mechanism of action for treatment of AD with FQD.

CONCLUSION

This study contributes to an understanding of the neuroprotective effect of FQD and its potential mechanism of action for the treatment of AD.