Dihuang-Yinzi Alleviates Cognition Deficits via Targeting Energy-Related Metabolism in an Alzheimer Mouse Model as Demonstrated by Integration of Metabolomics and Network Pharmacology

Integrated network pharmacology and brain metabolomics to analyze the mechanism of Dihuang Yinzi intervention in Alzheimer's disease

Ethnopharmacological relevance

Alzheimer's disease (AD) is an incurable neurodegenerative disease that has become one of the most important diseases threatening global public health security. Dihuang Yinzi (DHYZ) is a traditional Chinese medicine that has been widely used for the treatment of AD and has significant therapeutic effects, but its specific mechanism of action is still unclear.The aim of the study is to investigate the specific mechanism of DHYZ in treating AD based on brain metabolomics and network pharmacology.

Materials and methods

In this study, the classic APPswe/PS1E9 (APP/PS1) mice were selected as the AD animal model, and the mechanism of DHYZ was studied. The learning and memory ability of mice was detected by Y-maze test, and the ultrastructure of neural cells in the brain of the mice was observed by transmission electron microscope (TEM). Then, the mechanism of DHYZ intervention in AD was analyzed by constructing network pharmacology, and combined with brain metabolomics based on ultra performance liquid chromatography-mass spectrometry (UPLC-MS) to detect differential metabolic markers and their metabolic pathways. In addition, a joint analysis of differential metabolites and potential targets for DHYZ treatment of AD is conducted to deeply explore the relationship between key targets, differential metabolites, and metabolic pathways.

Results

After 30 days of DHYZ treatment, the spatial work and reference memory ability of APP/PS1 mice were significantly improved, the structure of mitochondria and synapses in the neurons of the brain were basically normal. 202 potential targets for DHYZ treatment of AD were screened through network pharmacology, and after enrichment analysis, these targets showed correlation with redox reactions, mitochondrial and synaptic functional pathways. And 7 differential metabolites were identified in brain metabolomics are Nicotinic acid, N-Formyl-L-glutamic acid, 5-(2-Hydroxyethyl)-4-methylthiazole, D-Gulono-1,4-lactone, Norepinephrine, 3-Methylotrophicacid, Palmitic acid. These differential metabolites mainly involve nicotinite and nicotinamide metabolism, pertussis, cAMP signaling pathway, cysteine and methionine metabolism. Notablely, through matching analysis of targets and metabolites, a total of 20 genes were found to match Nicotinic acid, 51 genes were found to match norepinephrine, and 14 genes intersected with the two metabolites, enrichment analysis of the intersected genes showed that neuroactive light receptor interaction, serotonergic synapse, and cAMP signaling were significantly affected, which is consistent with previous network pharmacology results.

Conclusion

This study identified the main chemical ingredients of DHYZ intervention in AD may originated from Polygala tenuifolia Wild, Dendrobium nobile Line and Ophiogon japonicus (L.f) Ker-Gawl. Combined with Y Maze, TEM and brain metabolomics, revealed that DHYZ can improve the learning and memory abilities and brain pathological morphology of APP/PS1 mice by regulating nicotinic acid, 3-Methylthiopropionic acid, pertussis and their metabolic pathways, including nicotinate and nicotinamide metabolism, cAMP signaling pathway and cysteine and methionine metabolism. In short, this study provides a new research foundation and direction for the treatment of AD with traditional Chinese medicine.

Exploring the adverse effects of 1,3,6,8-tetrabromo-9H-carbazole in atherosclerotic model mice by metabolomic profiling integrated with mechanism studies in vitro

Given its wide distribution in the environment and latent toxic effects, 1,3,6,8-tetrabromo-9H-carbazole (1368-BCZ) is an emerging concern that has gained increasing attention globally. 1368-BCZ exposure is reported to have potential cardiovascular toxicity. Although atherosclerosis is a cardiovascular disease and remains a primary cause of mortality worldwide, no evidence has been found regarding the impact of 1368-BCZ on atherosclerosis. Therefore, we aimed to explore the deleterious effects of 1368-BCZ on atherosclerosis and the underlying mechanisms. Serum samples from 1368-BCZ-treated atherosclerotic model mice were subjected to metabolomic profiling to investigate the adverse influence of the pollutant. Subsequently, the molecular mechanism associated with the metabolic pathway of atherosclerotic mice that was identified following 1368-BCZ exposure was validated in vitro. Serum metabolomics analysis revealed that 1368-BCZ significantly altered the tricarboxylic acid cycle, causing a disturbance in energy metabolism. In vitro, we further validated general markers of energy metabolism based on metabolome data: 1368-BCZ dampened adenosine triphosphate (ATP) synthesis and increased reactive oxygen species (ROS) production. Furthermore, blocking the aryl hydrocarbon receptor (AhR) reversed the high production of ROS induced by 1368-BCZ. It is concluded that 1368-BCZ decreased the ATP synthesis by disturbing the energy metabolism, thereby stimulating the AhR-mediated ROS production and presumably causing aggravated atherosclerosis. This is the first comprehensive study on the cardiovascular toxicity and mechanism of 1368-BCZ based on rodent models of atherosclerosis and integrated with in vitro models.

Targeting NAD Metabolism for the Therapy of Age-Related Neurodegenerative Diseases

As the aging population continues to grow rapidly, age-related diseases are becoming an increasing burden on the healthcare system and a major concern for the well-being of elderly individuals. While aging is an inevitable process for all humans, it can be slowed down and age-related diseases can be treated or alleviated. Nicotinamide adenine dinucleotide (NAD) is a critical coenzyme or cofactor that plays a central role in metabolism and is involved in various cellular processes including the maintenance of metabolic homeostasis, post-translational protein modifications, DNA repair, and immune responses. As individuals age, their NAD levels decline, and this decrease has been suggested to be a contributing factor to the development of numerous age-related diseases, such as cancer, diabetes, cardiovascular diseases, and neurodegenerative diseases. In pursuit of healthy aging, researchers have investigated approaches to boost or maintain NAD levels. Here, we provide an overview of NAD metabolism and the role of NAD in age-related diseases and summarize recent progress in the development of strategies that target NAD metabolism for the treatment of age-related diseases, particularly neurodegenerative diseases.

Study on the underlying mechanism of Poria in intervention of arrhythmia zebrafish by integrating metabolomics and network pharmacology

BACKGROUND

Poria is an herb with both medicinal and dietary application. It has been used in various traditional Chinese patent medicines and medicinal decoctions for the treatment of arrhythmia. However, the specific mechanisms involved in the antiarrhythmic effects of Poria have, until now, remained unknown.

PURPOSE

This present study sought to explore the potential compounds and mechanisms by which Poria ameliorates BaCl2-induced arrhythmia.

METHOD

We initiated by using network pharmacology to predict probable components, targets, and associated signaling pathways before optimizing the extraction process of Poria. We then applied Poria extract to a zebrafish model of BaCl2-induced arrhythmia. We combined network pharmacology and untargeted metabolomic analysis to predict the likely signaling and metabolic pathways governed by Poria. Finally, we verified putative mRNA and metabolite targets of Poria involved in the intervention of arrhythmia by PCR, molecular docking, enzymatic inhibition and targeted metabolomics.

RESULTS

We found that triterpenoids may be the main components of Poria responsible for its effects on arrhythmia, and that the optimal extraction process for its water extract is 9 volumes of water with the 7.5 h first extraction period, and the second extraction period of 1.5 h. Through experimentation, we have found that the water extract of Poria can interfere with BaCl2 induced arrhythmia in zebrafish by significantly increasing the heart rate, reducing the SV-BA distance, and pericardial area, and the degree of cardiomyocyte apoptosis in zebrafish. In addition, PCR validation revealed that Poria can regulate the calcium signaling pathway by upregulating the gene expression levels of ADRB1, HTR7, CALMB1, and PPP3CA. Meanwhile, through molecular docking and enzyme activity inhibition, it was found that the compounds in Poria can bind to ADRB1, HTR7, CALMB1, and PPP3CA, respectively. Targeted metabolism confirmed that Poria can downregulate the synthesis of cAMP in the calcium signaling pathway, as well as the synthesis of valine and isoleucine in valine, leucine, and isoleucine biosynthesis.

CONCLUSION

Overall, our study indicates that Poria exerts its antiarrhythmic effect through regulating the calcium signaling pathway and valine, leucine, and isoleucine biosynthesis. Our findings not only establish a mechanistic framework for elucidating the antiarrhythmic effects of Chinese patent medicine containing Poria, but also provide a medicinal basis for the study of its dual use as medicine and food.

Effects of Xiaoyao San on exercise capacity and liver mitochondrial metabolomics in rat depression model

Objective

This study aimed to investigate the therapeutic effects of Xiaoyao San (XYS), a herbal medicine formula, on exercise capacity and liver mitochondrial metabolomics in a rat model of depression induced by chronic unpredictable mild stress (CUMS).

Methods

A total of 24 male SD rats were randomly divided into four groups: control group (C), CUMS control group (M), Venlafaxine positive treatment group (V), and XYS treatment group (X). Depressive behaviour and exercise capacity of rats were assessed by body weight, sugar-water preference test, open field test, pole test, and rotarod test. The liver mitochondria metabolomics were analyzed by using liquid chromatography-mass spectrometry (LC-MS) method. TCMSP database and GeneCards database were used to screen XYS for potential targets for depression, and GO and KEGG enrichment analyses were performed.

Results

Compared with C group, rats in M group showed significantly lower body weight, sugar water preference rate, number of crossing and rearing in the open field test, climbing down time in the pole test, and retention time on the rotarod test (P < 0.01). The above behaviors and exercise capacity indices were significantly modulated in rats in V and X groups compared with M group (P < 0.05, 0.01). Compared with C group, a total of 18 different metabolites were changed in the liver mitochondria of rats in M group. Nine different metabolites and six metabolic pathways were regulated in the liver mitochondria of rats in X group compared with M group. The results of network pharmacology showed that 88 intersecting targets for depression and XYS were obtained, among which 15 key targets such as IL-1β, IL-6, and TNF were predicted to be the main differential targets for the treatment of depression. Additionally, a total of 1 553 GO signaling pathways and 181 KEGG signaling pathways were identified, and the main biological pathways were AGE-RAGE signaling pathway, HIF-1 signaling pathway, and calcium signaling pathway.

Conclusion

XYS treatment could improve depressive symptoms, enhance exercise capacity, positively regulate the changes of mitochondrial metabolites and improve energy metabolism in the liver of depressed rats. These findings suggest that XYS exerts antidepressant effects through multi-target and multi-pathway.

Therapeutic application of natural products: NAD+ metabolism as potential target

BACKGROUND

Nicotinamide adenine dinucleotide (NAD⁺) metabolism is involved in the entire physiopathological process and is critical to human health. Long-term imbalance in NAD⁺ homeostasis is associated with various diseases, including non-alcoholic fatty liver disease, diabetes mellitus, cardiovascular diseases, neurodegenerative disorders, aging, and cancer, making it a potential target for effective therapeutic strategies. Currently, several natural products that target NAD⁺ metabolism have been widely reported to have significant therapeutic effects, but systematic summaries are lacking.

PURPOSE

To summarize the latest findings on the prevention and treatment of various diseases through the regulation of NAD⁺ metabolism by various natural products in vivo and in vitro models, and evaluate the toxicities of the natural products.

METHODS

PubMed, Web of Science, and ScienceDirect were searched using the keywords "natural products sources," "toxicology," "NAD⁺ clinical trials," and "NAD⁺," and/or paired with "natural products" and "diseases" for studies published within the last decade until January 2023.

RESULTS

We found that the natural products mainly include phenols (curcumin, cyclocurcumin, 4-hydroxybenzyl alcohol, salvianolic acid B, pterostilbene, EGCG), flavonoids (pinostrobin, apigenin, acacetin, tilianin, kaempferol, quercetin, isoliquiritigenin, luteolin, silybin, hydroxysafflor yellow A, scutellarin), glycosides (salidroside), quinones (emodin, embelin, β-LAPachone, shikonin), terpenoids (notoginsenoside R1, ginsenoside F2, ginsenoside Rd, ginsenoside Rb1, ginsenoside Rg3, thymoquinone, genipin), pyrazines (tetramethylpyrazine), alkaloids (evodiamine, berberine), and phenylpropanoids (ferulic acid). These natural products have antioxidant, energy-producing, anti-inflammatory, anti-apoptotic and anti-aging effects, which mainly influence the NAMPT/NAD⁺/SIRT, AMPK/SIRT1/PGC-1α, Nrf2/HO-1, PKCs/PARPs/NF-κB, and AMPK/Nrf2/mTOR signaling pathways, thereby regulating NAD⁺ metabolism to prevent and treat various diseases. These natural products have been shown to be safe, tolerable and have fewer adverse effects in various in vivo and in vitro studies and clinical trials.

CONCLUSION

We evaluated the toxic effects of natural products and summarized the available clinical trials on NAD⁺ metabolism, as well as the recent advances in the therapeutic application of natural products targeting NAD⁺ metabolism, with the aim to provide new insights into the treatment of multiple disorders.