Jia-Wei-Kai-Xin-San, an Herbal Medicine Formula, Ameliorates Cognitive Deficits via Modulating Metabolism of Beta Amyloid Protein and Neurotrophic Factors in Hippocampus of Aβ1-42 Induced Cognitive Deficit Mice

Jia-Wei-Kai-Xin-San Treatment Alleviated Mild Cognitive Impairment through Anti-Inflammatory and Antiapoptotic Mechanisms in SAMP8 Mice

Background

Alleviating mild cognitive impairment (MCI) is crucial to delay the progression of Alzheimer's disease (AD). Jia-Wei-Kai-Xin-San (JWKXS) is applied for treating AD with MCI. However, the mechanism of JWKXS in the treatment of MCI is unclear. Thus, this study aimed to investigate the effect and mechanism of JWKXS in SAMP8 mice models of MCI.

Methods

MCI models were established to examine learning and memory ability and explore the pathomechanisms in brain of SAMP8 mice at 4, 6, and 8 months. The mice were treated for 8 weeks and the effects of JWKXS on MCI were characterized through Morris water maze and HE/Nissl's/immunohistochemical staining. Its mechanism was predicted by the combination of UPLC-Q-TOF/MS and system pharmacology analysis, further verified with SAMP8 mice, BV2 microglial cells, and PC12 cells.

Results

It was found that 4-month-old SAMP8 mice exhibited MCI. Two months of JWKXS treatment improved the learning and memory ability, alleviated the hippocampal tissue and neuron damage. Through network pharmacology, four key signaling pathways were found to be involved in treatment of MCI by JWKXS, including TLR4/NF-κB pathway, NLRP3 inflammasome activation, and intrinsic and extrinsic apoptosis. In vitro and in vivo experiments demonstrated that JWKXS attenuated neuroinflammation by inhibiting microglia activation, suppressing TLR4/NF-κB and NLRP3 inflammasome pathways, and blocking the extrinsic and intrinsic apoptotic pathways leading to neuronal apoptosis suppression in the hippocampus.

Conclusion

JWKXS treatment improved the learning and memory ability and conferred neuroprotective effects against MCI by inducing anti-inflammation and antiapoptosis. Limitations. The small sample size and short duration of the intervention limit in-depth investigation of the mechanisms. Future Prospects. This provides a direction for further clarification of the anti-AD mechanism, and provides certain data support for the formulation to move toward clinical practice.

Neurovascular glial unit: A target of phytotherapy for cognitive impairments

BACKGROUND

Neurovascular glial unit (NVGU) dysfunction has been reported to be an early and critical event in the pathophysiology of Alzheimer's disease (AD) and vascular dementia (VD). Although herbal medicines, with their favorable safety profiles and low adverse effects, have been suggested to be useful for the treatment of cognitive impairment, the potential role of the NVGU as the target of the effects of herbal medicines is still unclear.

PURPOSE

This review aimed to retrieve evidence from experimental studies of phytopharmaceuticals targeting the NVGU for the treatment of cognitive impairment in AD and VD, and discussed the potential of phytopharmaceuticals to improve cognitive impairment from the perspective of the NVGU.

STUDY DESIGN AND METHODS

We systematically searched PubMed, Google Scholar, Web of Science, and CNKI. The keywords used for searching information on the NVGU in the treatment of cognitive impairments included "Alzheimer's disease," "Vascular dementia," "Herbal medicines," "Natural products," "Neurovascular," "Adverse reaction," and "Toxicity, etc." We selected studies on the basis of predefined eligibility criteria.

RESULTS

NVGU mainly consists of endothelial cells, pericytes, astrocytes, microglia, oligodendrocytes, and neurons, and damage to these cells can induce cognitive impairment by impairing the blood-brain barrier (BBB) and cerebral blood flow (CBF) as well as neuronal function. The active components of herbal medicines, including Ginkgo biloba L., Ginseng Radix et Rhizoma, Epimedium Folium, Chuanxiong Rhizoma, Carthami flos, and Acorus tatarinowii Schott, as well as traditional Chinese medicine prescriptions have shown the potential to improve BBB function and increase CBF to prevent cognitive impairment by inhibiting astrocyte and microglia activation, protecting oligodendrocyte myelin function, reducing neuronal apoptosis, and promoting angiogenesis.

CONCLUSIONS

Herbal medicines demonstrate great potential to prevent cognitive impairment. Multiple components from herbal medicines may function through different signaling pathways to target the NVGU. Future studies using novel drug-carrier or delivery systems targeting the NVGU will certainly facilitate the development of phytopharmaceuticals for AD and VD.

Jian-Yan-Ling capsules ameliorate cognitive impairment in mice with D-galactose-induced senescence and inhibit the oxidation-induced apoptosis of HT22 hippocampal cells by regulating the Nrf2-HO1 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

The Jian-Yan-Ling (JYL) capsule is a famous anti-aging Chinese patent medicine. It is applied mainly to delay senescence to improve cognition in aging individuals. However, the action mechanisms of JYL for improving cognition have not been determined.

AIM OF THE STUDY

We will evaluate the effect of the JYL capsule at improving the cognition of aging mice by improving oxidative stress in the hippocampus and exploring its action mechanism.

MATERIALS AND METHODS

A senescence mouse model was developed via intraperitoneal injection of D-galactose. The effect of the JYL capsule at improving the learning and memory abilities of mice was evaluated using the Morris water maze and novel object recognition tests. The apotosis of model mice hippocampus' were determined by TUNEL analysis. The antioxidant capacity of the JYL capsule was evaluated by determining the activities of antioxidant enzymes and expressions of oxidative products. The regulation of the Nrf2/HO-1 signaling pathway of the JYL capsule was evaluated by determining the expressions of related proteins via western blotting analysis. In vitro, H₂O₂-treated mouse hippocampal HT22 cells were used to evaluate the antioxidant capacity of JYL-containing rat serum by determining the cell viability, apoptotic level and expressions of related proteins.

RESULTS

JYL capsules enhanced the learning and memory abilities of model mice according to behavioral tests. The results of TUNEL analysis showed that the JYL capsule ameliorated hippocampal apoptosis in model mice. JYL capsules also exerted significant antioxidant capacity by increasing the activities of antioxidant enzymes while decreasing the levels of oxidative products both in the hippocampus and serum. The regulation of Nrf2/HO-1 pathway might contribute to the antioxidant function. In vitro, JYL-containing rat serum protected HT22 cells from H₂O₂ induced oxidative stress. The apoptosis of HT22 cells was also attenuated by regulating the caspase and Nrf2/HO-1 signaling pathways.

CONCLUSIONS

The amelioration of neuronal oxidative stress of hippocampus might contribute to the D-galactose-induced cognition impairment of senescence mice. These findings provide evidence for the application of JYL capsules to enhance cognition in aging individuals.

Chinese Medicine, Succinum, Ameliorates Cognitive Impairment of Carotid Artery Ligation Rats and Inhibits Apoptosis of HT22 Hippocampal Cells via Regulation of the GSK3β/β-Catenin Pathway

Succinum is an organic mineral formed from the resin of ancient coniferous and leguminous plants, which is applied for tranquilizing mood, promoting blood circulation, and removing blood stasis in Chinese medicine. For quite a long time, the modern research of succinum mainly focuses on the study of physical and chemical properties and authenticity identification while few reports on its medicinal mechanism. In current study, we evaluated different solvent extracts of succinum on carotid artery ligation rats mimicking vascular dementia. It was found that ethyl acetate extracts of succinum significantly improved the learning and memory abilities of model rats and inhibited neuronal apoptosis in the hippocampus. On a mice hippocampal neuronal cell line (HT22), ethyl acetate extracts of succinum also exerted better action trend in inhibiting cell apoptosis induced by oxygen glucose deprivation (OGD). By using XAV-939 on both in vivo and in vitro studies, it was found that ethyl acetate extracts of succinum might exert these functions by regulating the GSK3β/β-catenin pathway. These studies revealed the neuronal function of succinum, which explained the traditional effects of succinum and provided more modern scientific basis for its clinical application.

Relationships Between Traditional Chinese Medicine Constitution and Age-Related Cognitive Decline in Chinese Centenarians

Background

Age-related cognitive decline (ARCD) is a common condition among older adults, affecting 100 million people worldwide. Traditional Chinese Medicine’s (TCM) constitution is closely related to the occurrence and development of diseases in the elderly population. However, little is known about the relationships between TCM constitution and ARCD in the super-aged population. The present study aimed to investigate the relationships between the TCM constitution and ARCD in Chinese centenarians and to explore the application of the constitution to prevent ARCD in the elderly population.

Methods

Each participant underwent a standardized epidemiological investigation and physical examination, based on the China Hainan Centenarian Cohort Study. Data on the demographic characteristics and TCM constitution were collected using structured questionnaires.

Results

The present study included 636 centenarians aged 100–116 years. The prevalence of ARCD was 87.7% (n = 558 centenarians). In multiple linear regression analysis, an inverse relationship between Qi depression and Mini-Mental State Examination scales was significant after controlling for a wide range of other factors (P < 0.05). In multiple logistic regression analysis, Qi depression was positively associated with ARCD after full adjustment (P < 0.05).

Conclusion

As the first study in the world, the present study provides strong epidemiological evidence that Qi depression has a significant relationship with ARCD in Chinese centenarians, and regulating Qi depression may be a valuable method to prevent and treat ARCD in the elderly population.

Senegenin Inhibits Aβ1-42-Induced PC12 Cells Apoptosis and Oxidative Stress via Activation of the PI3K/Akt Signaling Pathway

BACKGROUND/AIM

Apoptosis and oxidative stress have been considered as key events in the pathogenesis of Alzheimer's disease (AD). Senegenin (Sen), the major and most effective ingredient of Radix Polygalae, which has anti-apoptotic and anti-oxidative effects. The aim of this study was to investigate the anti-apoptotic and anti-oxidant effects of Sen on Aβ_1-42-induced PC12 cells apoptosis and oxidative stress as well as its possible signaling pathway.

METHODS

Rat pheochromocytoma (PC12) cells were treated by 20 μM Aβ_1-42 and then divided into 5 different treatment groups (Control; Aβ_1-42 20 μM; Aβ_1-42 20 μM + Sen 10 μM; Aβ_1-42 20 μM + Sen 30 μM; Aβ_1-42 20μM + Sen 60 μM). PC12 cells activity was detected by MTT assay. Colony formation assay was performed to assess the clonogenic ability of cells. The cell apoptosis was detected by Annexin-V/PI staining. The pro-apoptotic protein (Bax), anti-apoptotic protein (Bcl-2), anti-oxidative stress factor (HO-1, Nuclear Nrf2, Total Nrf2) and pathway-related protein (Akt, P-Akt, PI3K, P-PI3K) were tested by Western blot. The reactive oxygen species (ROS) level was assessed with a DCFH-DA probe.

RESULTS

The results indicated that Sen dose-dependently increased cell viability and reduced the number of apoptotic cells. The ratio of P-PI3K/PI3K and P-Akt/Akt increased in a dose-dependent manner under the treatment of Sen, suggesting that Sen might activate the PI3K/Akt signaling pathway. Moreover, Sen upregulates the ratio of Bcl-2/Bax. Further study revealed that Sen can play an antioxidant role in enhancing HO-1, promoting Nrf2 nuclear translocation and reducing ROS accumulation to reduce oxidative stress.

CONCLUSION

Sen is effective in inhibiting apoptosis and oxidative stress in Aβ_1-42-induced PC12 cells, which likely contribute to the development of novel therapies for AD.

β-Asarone Ameliorates β-Amyloid-Induced Neurotoxicity in PC12 Cells by Activating P13K/Akt/Nrf2 Signaling Pathway

Accumulation of β-amyloid (Aβ) causes oxidative stress, which is the major pathological mechanism in Alzheimer's disease (AD). β-asarone could reduce Aβ-induced oxidative stress and neuronal damage, but the molecular mechanism remains elusive. In this study, we used an Aβ-stimulated PC12 cell model to explore the neuroprotective effects and potential mechanisms of β-asarone. The results showed that β-asarone could improve cell viability and weaken cell damage and apoptosis. β-asarone could also decrease the level of ROS and MDA; increase the level of SOD, CAT, and GSH-PX; and ameliorate the mitochondrial membrane potential. Furthermore, β-asarone could promote the expression of Nrf2 and HO-1 by upregulating the level of PI3K/Akt phosphorylation. In conclusion, β-asarone could exert neuroprotective effects by modulating the P13K/Akt/Nrf2 signaling pathway. β-asarone might be a promising therapy for AD.

Quercetin-3-O-Glucuronide Alleviates Cognitive Deficit and Toxicity in Aβ1-42 -Induced AD-Like Mice and SH-SY5Y Cells

SCOPE

Alzheimer's disease (AD) is characterized by amyloid-β (Aβ) related imbalance, Tau-hyperphosphorylation, and neuroinflammation, in which Aβ and neuroinflammation can induce brain insulin resistance (IR). Gut microbiome disorder is correlated with inflammation in AD. As of yet, there are no effective treatments clinically. Thus, it is focused on the potential benefit of quercetin-3-O-glucuronide (Q3G), a pharmacologically active flavonol glucuronide, on AD treatment by regulating brain IR and the gut microbiome.

METHODS AND RESULTS

AD mice model built through intracerebroventricular injection of Aβ1-42 and AD cell model developed through the SH-SY5Y cell line and Aβ1-42 are used to explore the protective effects of Q3G on AD. Neurobehavioral test, brain insulin signaling pathway, and high-throughput pyrosequencing of 16S rRNA are assessed. Data show that Q3G attenuates neuroinflammation and brain IR in Aβ1-42 -injected mice and relieves apoptosis in Aβ1-42 -treated SH-SY5Y cells by interrupting the downstream insulin signaling. Q3G ameliorates Aβ accumulation and Tau phosphorylation, restores CREB and BDNF levels in the hippocampus , and reverses Aβ1-42 -induced cognitive impairment. Besides, Q3G restores Aβ1-42 -induced reduction of short-chain fatty acids (SCFAs) and gut microbiota dysbiosis.

CONCLUSION

Q3G can alleviate brain IR through directly acting on the brain or modulating the gut-brain axis, ultimately to relieve Aβ1-42 -induced cognitive dysfunction.