Classic Famous Prescription Kai-Xin-San Ameliorates Alzheimer's Disease via the Wnt/β-Catenin Signaling Pathway

Acori Tatarinowii Rhizoma regulates OCT3/OATP2 and P-gp/MRP1 to "guide medicines upwards" in Kai-Xin-San to treat Alzheimer's disease

ETHNOPHARMACOLOGICAL RELEVANCE

Kai-Xin-San (KXS) has a significant effect therapeutic on Alzheimer's disease (AD) in clinical practice. According to the compatibility theory of traditional Chinese medicine, Acori Tatarinowii Rhizoma (ATR) serves as the guiding drug in the KXS formulation and is believed to enhance the bioavailability and brain tissue distribution of the other drugs. However, the mechanism underlying the "guiding medicine upwards" effect of ATR in KXS remains unexplored.

AIM OF THE STUDY

The aim of this study is to investigate the role of ATR in the efficacy of KXS on amyloid precursor protein/presenilin 1 (APP/PS1) mice, as well as its impact on the brain tissue distribution of other active ingredients in the KXS formula, and to elucidate the mechanism of ATR's "guiding medicine upwards" effect in KXS.

MATERIALS AND METHODS

The pharmacodynamic effects of ATR in KXS were assessed through behavioral tests, immunohistochemical staining, and Nissl staining. Additionally, the levels of inflammatory factors, as well as the activities of malondialdehyde, superoxide dismutase, and acetylcholinesterase, were measured using enzyme-linked immunosorbent assay kits. Subsequently, the effect of ATR on the ultrastructure of the blood-brain barrier (BBB) in APP/PS1 mice was observed using transmission electron microscopy (TEM), and the pharmacodynamic components of KXS in cerebrospinal fluid were quantified by ultra-high-performance liquid chromatography-triple quadrupole mass spectrometry (UPLC-MS/MS). Furthermore, Western blot (WB) analysis was used to quantitatively assess the expression of tight junction proteins (Claudin-5, Occludin, and ZO-1) and transporters (OCT3, OATP2, P-gp, and MRP1) in the BBB. Finally, bEND.3 cells and astrocyte cells were co-cultured to validate the effect of ATR on KXS. The expressions of OCT3/OATP2 and P-gp/MRP1 in BBB cell model were determined by WB and the content of pharmacodynamic components in the lower chamber of the transwell were also analyzed by UPLC-MS/MS.

RESULTS

Behavioral test results suggest that KXS significantly improved the learning and memory capacities of APP/PS1 mice compared to the ATR-free KXS group. Furthermore, KXS was more effective in reducing amyloid-β protein deposition in the brain and repairing damaged neurons in the CA1 and CA3 regions than ATR-free KXS. Notably, KXS significantly reversed the pathological biochemical indices compared to the ATR-free KXS group. These results indicate that ATR has a positive effect on the pharmacodynamics of KXS in treating AD. Most importantly, TEM results revealed that KXS repaired the damaged BBB in AD mice, and ATR contributed to the improvement of BBB integrity. Furthermore, KXS and ATR increased the expression levels of Claudin-5, Occludin, and ZO-1 proteins in AD mice. Meanwhile, the levels of ginsenoside Rg1, ginsenoside Rb1, and polygalaxanthone III in the cerebrospinal fluid of the KXS group were 1.47, 1.39, and 2.02 times higher than those in the ATR-free KXS group, respectively. WB results showed that ATR and KXS significantly upregulated the expression of OCT3/OATP2 uptake transporters and downregulated the expression of P-gp/MRP1 efflux transporters compared to ATR-free KXS. Concurrently, in vitro BBB cell experimental results suggest that ATR promoted the transport of ginsenoside Rg1, ginsenoside Rb1, and polygalaxanthone III across BBB cells in KXS, and the regulation of OCT3/OATP2 and P-gp/MRP1 expression was consistent with the in vivo trends observed in AD mice.

CONCLUSIONS

ATR plays a critical role in enhancing the efficacy of KXS in treating AD and facilitates the entry of other pharmacodynamic components into the brain. The mechanism underlying the "guiding medicine upwards" effect of ATR may involve the regulation of OCT3/OATP2 and P-gp/MRP1 transporters.

Unlocking Hope: Therapeutic Advances and Approaches in Modulating the Wnt Pathway for Neurodegenerative Diseases

Neurodegenerative diseases (NDs) are conditions characterized by sensory, motor, and cognitive impairments due to alterations in the structure and function of neurons in the central nervous system (CNS). Despite their widespread occurrence, the exact causes of NDs remain largely elusive, and existing treatments fall short in efficacy. The Wnt signaling pathway is an emerging molecular pathway that has been linked to the development and progression of various NDs. Wnt signaling governs numerous cellular processes, such as survival, polarity, proliferation, differentiation, migration, and fate specification, via a complex network of proteins. In the adult CNS, Wnt signaling regulates synaptic transmission, plasticity, memory formation, neurogenesis, neuroprotection, and neuroinflammation, all essential for maintaining neuronal function and integrity. Dysregulation of both canonical and non-canonical Wnt signaling pathways contributes to neurodegeneration through various mechanisms, such as amyloid-β accumulation, tau protein hyperphosphorylation, dopaminergic neuron degeneration, and synaptic dysfunction, prompting investigations into Wnt modulation as a therapeutic target to restore neuronal function and prevent or delay neurodegenerative processes. Modulating Wnt signaling has the potential to restore neuronal function and impede or postpone neurodegenerative processes, offering a therapeutic approach for targeting NDs. In this article, the current knowledge about how Wnt signaling works in Alzheimer's disease and Parkinson's disease is discussed. Our study aims to explore the molecular mechanisms, recent discoveries, and challenges involved in developing Wnt-based therapies.

Bioactive compounds from Chinese herbal plants for neurological health: mechanisms, pathways, and functional food applications

Neurological disorders pose significant global public health challenges, with a rising prevalence and complex pathophysiological mechanisms that impose substantial social and economic burdens. Traditional Chinese Medicine (TCM), with its holistic approach and multi-target effects, has gained increasing attention in the treatment of neurological diseases. This review explores bioactive compounds derived from Chinese herbal plants, focusing on their mechanisms of action, underlying pathways, and potential applications in functional food development. The review highlights the neuroprotective properties of flavonoids, alkaloids, polysaccharides, and polyphenols found in key TCM herbs such as Scutellaria baicalensis, Salvia miltiorrhiza, Ligusticum chuanxiong, and Gastrodia elata. These compounds have demonstrated significant anti-inflammatory, antioxidant, and neurogenic effects, making them promising candidates for the prevention and treatment of neurological conditions, including Alzheimer's disease (AD), Parkinson's disease (PD), and depression. Furthermore, the synergistic effects of TCM formulations targeting multiple signaling pathways offer advantages over single-target therapies, especially in combating neurodegenerative diseases. The review also discusses the challenges and future directions for integrating these bioactive compounds into functional foods and dietary supplements, aiming to improve neurological health and enhance clinical outcomes. Ultimately, this work aims to provide valuable insights into the potential of TCM-based interventions for promoting neurological well-being and addressing the global burden of neurological disorders.

Evaluation of the chronic oral toxicity of the classical ancient prescription Kai-Xin-San

ETHNOPHARMACOLOGICAL RELEVANCE

The Kai-Xin-San (KXS), as an ancient classic prescription, has been used for the treatment of amnesia for thousands of years. Modern clinical and non-clinical pharmacological studies have found that it has significant therapeutic effects on dementia and depression, but there are relatively few studies on its safety.

AIM OF THE STUDY

Subacute and chronic toxicity studies were conducted to investigate the symptoms, severity, target organs, development and recovery of toxic reactions, as well as the toxic dose. These studies provide technical data for ensuring the safety of KXS.

MATERIALS AND METHODS

In the sub-acute toxicity study, rats were orally administered KXS at doses of 0.80, 1.61, 3.22, and 6.43 g/kg body weight for a duration of 4 weeks. In the chronic toxicity study, rats were orally administered KXS at doses of 0.27, 0.81, and 2.43 g/kg body weight for a duration of 26 weeks, and a withdrawal study was conducted for a period of 4 weeks after the treatment.The rats were observed daily for clinical signs and mortality. Changes in body weight, food consumption, and water consumption were periodically monitored. Additionally, urinalysis results, hematological and biochemical parameters, relative organ weights, and pathology were monitored at specific observation time points.

RESULTS

In the sub-acute toxicity study, necropsy of dead and moribund rats revealed evident distension and swelling of the gastrointestinal tract, as well as thinning of the intestinal wall. The main adverse reactions observed included flatulence, piloerection, abnormal breathing sounds, and emaciation. Doses of 1.61 g/kg and below did not cause animal death. The gastrointestinal system is the main target organ of toxicity. In the chronic toxicity study, the no-observed-adverse-effect-level (NOAEL) of KXS was 0.27 g/kg, and its toxic effects were primarily concentrated in the gastrointestinal system. This led to secondary pathological changes in the immune system, hematopoietic system, and heart, suggesting that relevant indicators should be monitored when large doses are used clinically for an extended period of time.

CONCLUSIONS

During the rodent toxicity evaluation, severe gastrointestinal damage was observed when KXS, powdered with crude drugs, was administered. The NOAEL for rats was found to be 0.27 g/kg/day.

KaiXinSan improves learning and memory impairment by regulating cholesterol homeostasis in mice overloaded with 27-OHC

Cholesterol and its oxidative products-oxysterols homeostasis- play a crucial role in maintaining cognitive function. Chinese medicine KaiXinSan (KXS) has demonstrated effectiveness in treating mental illness and regulating cognitive dysfunction of Alzheimer's disease (AD). The purpose of this article is to explore whether the KXS can enhance cognitive function by regulating cholesterol homeostasis. Employing the 27-hydroxy cholesterol (27-OHC) induced mice model of cognitive dysfunction and coculture model of assessment neurocyte damage, we investigated learning and memory abilities while concurrently addressing the reduction of neuronal cell damage through the regulation of cholesterol metabolism. 21 days of KXS treatment improved the learning and memory ability in mice 27-OHC-overloading by alleviating the exacerbated deposition of amyloid-β (Aβ), reducing inflammatory reactions, and mitigating synaptic plasticity damage. Additionally, it repaired myelin sheath function. More importantly, KXS significantly affects the metabolism of central cholesterol by substantially inhibiting the expression of liver X receptor (LXR), ATP-binding cassette transporter (ABCA1, ABCG1), apolipoprotein E (ApoE) and upregulated cytochrome P450 46A1(CYP46A1). Furthermore, KXS may alleviate 27-OHC-induced neuronal inflammation and apoptosis by promoting the conversion of cholesterol to 24-hydroxycholesterol (24-OHC) via CYP46A1 and suppressing cholesterol release from astrocyte cells. Altogether, our results demonstrate that KXS can prevent learning and memory impairments induced by 27-OHC loading. This effect may be related to its multitarget capability in promoting the conversion of excessive cholesterol to 24-OHC and maintaining a balance in cholesterol homeostasis and metabolism between neurons and astrocyte cells.

Identification of vilazodone as a novel plasminogen activator inhibitor to overcome Alzheimer's disease through virtual screening, molecular dynamics simulation, and biological evaluation

Urokinase-type plasminogen activator (PLAU), a member of the S1 serine peptidase family in Clan PA, plays a crucial role in the conversion of plasminogen into active plasmin. However, the precise role of PLAU in the central nervous system remains incompletely elucidated, particularly, in relation to Alzheimer's disease (AD). In this study, we successfully identified that PLAU could promote cell senescence in neurons, indicating it as a potential target for AD treatment through a systematic approach, which included both bioinformatics analysis and experimental verification. Subsequently, a structure-based virtual screening approach was employed to identify a potential PLAU inhibitor from the Food and Drug Administration-approved drug database. After analyzing docking scores and thoroughly examining the receptor-ligand complex interaction modes, vilazodone emerges as a highly promising PLAU inhibitor. Additionally, molecular docking and molecular dynamics simulations were performed to generate a complex structure between the relatively stable inhibitor vilazodone and PLAU. Of note, vilazodone exhibited superior cytotoxicity against senescent cells, showing a senolytic activity through targeting PLAU and ultimately producing an anti-AD effect. These findings suggest that targeting PLAU could represent a promising therapeutic strategy for AD. Furthermore, investigating the inhibitory potential and structural modifications based on vilazodone may provide valuable insights for future drug development targeting PLAU in AD disorders.

Herbal medicines in Alzheimer's disease and the involvement of gut microbiota

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by memory loss and cognitive impairment. It severely affects the quality of life of victims. The prevalence of AD has been increasing in recent years. Therefore, it is of great importance to elucidate the pathogenic mechanism of AD and search for effective therapeutic approaches. Gut microbiota dysbiosis, an altered state of gut microbiota, has been well known for its involvement in the pathogenesis of AD. Much effort has been made in searching for approaches capable of modulating the composition of gut microbiota in recent years. Herbal medicines have attracted extensive attention in recent decades for the prevention and treatment of AD. Here, we gave an overview of the recent research progress on the modulatory effects of herbal medicines and herbal formulae on gut microbiota as well as the possible beneficial effects on AD, which may provide new insights into the discovery of anti-AD agents and their therapeutic potential for AD through modulating the composition of gut microbiota.

Constituents, pharmacological activities, pharmacokinetic studies, clinical applications, and safety profile on the classical prescription Kaixinsan

Kaixinsan (KXS) is a noteworthy classical prescription, which consists of four Chinese medicinal herbs, namely Polygalae Radix, Ginseng Radix et Rhizoma, Poria, and Acori Tatarinowii Rhizoma. KXS was initially documented in the Chinese ancient book Beiji Qianjin Yaofang written by Sun Simiao of the Tang Dynasty in 652 A.D. As a traditional Chinese medicine (TCM) prescription, it functions to nourish the heart and replenish Qi, calm the heart tranquilize the mind, and excrete dampness. Originally used to treat amnesia, it is now also effective in memory decline and applied to depression. Although there remains an abundance of literature investigating KXS from multiple aspects, few reviews summarize the features and research, which impedes better exploration and exploitation of KXS. This article intends to comprehensively analyze and summarize up-to-date information concerning the chemical constituents, pharmacology, pharmacokinetics, clinical applications, and safety of KXS based on the scientific literature, as well as to examine possible scientific gaps in current research and tackle issues in the next step. The chemical constituents of KXS primarily consist of saponins, xanthones, oligosaccharide esters, triterpenoids, volatile oils, and flavonoids. Of these, saponins are the predominant active ingredients, and increasing evidence has indicated that they exert therapeutic properties against mental disease. Pharmacokinetic research has illustrated that the crucial exposed substances in rat plasma after KXS administration are ginsenoside Re (GRe), ginsenoside Rb1 (GRb1), and polygalaxanthone III (POL). This article provides additional descriptions of the safety. In this review, current issues are highlighted to guide further comprehensive research of KXS and other classical prescriptions.