Alisma orientalis Beverage Treats Atherosclerosis by Regulating Gut Microbiota in ApoE-/- Mice

Zexieyin formula alleviates Alzheimer's disease via post-synaptic CaMKII modulating AMPA receptor: Involved in promoting neurogenesis to strengthen synaptic plasticity in mice hippocampus

BACKGROUND

Alzheimer's disease (AD) is a serious neurodegenerative disease and brings a serious burden to society and families. Due to lack of effective drugs for the treatment of AD, it's urgent to develop new and effective drug for the treatment of AD.

PURPOSE

The study aimed to investigate the potential of Zexieyin formula (ZXYF), a Chinese medicine formula, for the treatment of AD and its potential mechanism of action.

METHODS

We used chronic scopolamine (SCOP) induction mice model and APP/PS1 mice to reveal and confirm ZXYF for the treatment of AD with donepezil (DON) as a positive reference. The learning and memory function were detected by morris water maze test (MWM) and y-maze test. Moreover, western blot and immunofluorescence were used to detect the molecular mechanism of ZXYF for the alleviation of AD in hippocampus. Lastly, pharmacological technology was applied to evaluate AMPA receptor involved in the role of ZXYF in the treatment of AD.

RESULTS

The results showed that ZXYF could improve memory and learning deficits both in two AD models including scopolamine (SCOP)-induced mice model and APP/PS1mice. Moreover, ZXYF or not DON increased expressions of BrdU/DCX and Ki67 positive cells in dentate gyrus (DG), up-regulated the levels of AMPA subunit type (GluA1) and PKA in hippocampus in SCOP-induced mice model, although ZXYF and DON activated CaMKII, CaMKII-phosphorylation, CREB, CREB-phosphorylation and PSD95 in hippocampus in SCOP-induced mice model. ZXYF also activated CaMKII, CaMKII-phosphorylation and GluA1 in HT22 cells. Furthermore, transient inhibiting AMPA receptor was capable of blocking the effects of ZXYF to treat AD in MWM and suppressing the number of BrdU/DCX positive cells increased by ZXYF in DG in SCOP-induced mice model, but had no effect on the alteration of Ki67 positive cells.

CONCLUSION

ZXYF had the therapeutic effects on AD-treatment, which activated CaMKII to promote AMPA receptor (GluA1) and subsequently up-regulated PKA/CREB signaling to facilitate neurogenesis to achieve enhanced postsynaptic protein.

From ancient wisdom to modern science: Gut microbiota sheds light on property theory of traditional Chinese medicine

The property theory of traditional Chinese medicine (TCM) has been practiced for thousands of years, playing a pivotal role in the clinical application of TCM. While advancements in energy metabolism, chemical composition analysis, machine learning, ion current modeling, and supercritical fluid technology have provided valuable insight into how aspects of TCM property theory may be measured, these studies only capture specific aspects of TCM property theory in isolation, overlooking the holistic perspective inherent in TCM. To systematically investigate the modern interpretation of the TCM property theory from multidimensional perspectives, we consulted the Chinese Pharmacopoeia (2020 edition) to compile a list of Chinese materia medica (CMM). Then, using the Latin names of each CMM and gut microbiota as keywords, we searched the PubMed database for relevant research on gut microbiota and CMM. The regulatory patterns of different herbs on gut microbiota were then summarized from the perspectives of the four natures, the five flavors and the meridian tropism. In terms of the four natures, we found that warm-natured medicines promoted the colonization of specific beneficial bacteria, while cold-natured medicines boosted populations of some beneficial bacteria while suppressing pathogenic bacteria. Analysis of the five flavors revealed that sweet-flavored and bitter-flavored CMMs positively influenced beneficial bacteria while inhibiting harmful bacteria. CMMs with different meridian tropism exhibited complex modulative patterns on gut microbiota, with Jueyin (Liver) and Taiyin (Lung) meridian CMMs generally exerting a stronger effect. The gut microbiota may be a biological indicator for characterizing the TCM property theory, which not only enhances our understanding of classic TCM theory but also contributes to its scientific advancement and application in healthcare. Please cite this article as: Yang YN, Zhan JG, Cao Y, Wu CM. From ancient wisdom to modern science: Gut microbiota sheds light on property theory of traditional Chinese medicine. J Integr Med 2024; 22(4): 413-445.

Lactobacillus delbrueckii Ameliorated Blood Lipids via Intestinal Microbiota Modulation and Fecal Bile Acid Excretion in a Ningxiang Pig Model

Lactobacillus delbrueckii intervention can regulate body lipid metabolism, but the underlying mechanism remains unclear. Our study investigated the effects of L. delbrueckii on serum lipid levels, tissular fat metabolism and deposition, bile acid metabolism, and gut microbiota in Ningxiang pigs. Ninety-six pigs were divided into two groups and fed basal diets containing either 0 (CON) or 0.1% L. delbrueckii (LD) for 60 days. Dietary L. delbrueckii promoted fecal total bile acid (TBA) excretion and increased hepatic enzyme activities related to cholesterol and bile synthesis but decreased hepatic and serum lipid concentrations. L. delbrueckii downregulated gene expression associated with fatty acid synthesis but upregulated gene expression related to lipolysis and β-fatty acid oxidation in liver and subcutaneous fat. L. delbrueckii elevated gut Lactobacillus abundance and colonic short-chain fatty acid (SCFA)-producing bacteria but declined the abundance of some pathogenic bacteria. These findings demonstrated that L. delbrueckii modulated intestinal microbiota composition and facilitated fecal TBA excretion to regulate hepatic fat metabolism, which resulted in less lipid deposition in the liver and reduced levels of serum lipids.

ZeXieYin formula alleviates atherosclerosis by inhibiting the MAPK/NF-κB signaling pathway in APOE-/- mice to attenuate vascular inflammation and increase plaque stability

ETHNOPHARMACOLOGICAL RELEVANCE

Zexieyin formula (ZXYF), a traditional Chinese herbal formula recorded in the Huangdi Neijing to have efficacy in relieving spleen dampness and heat accumulation syndrome, which is also the key pathogenesis of atherosclerosis (AS). The efficacy has demonstrated by our previous studies. However, the intrinsic mechanism of ZXYF for treating vascular inflammation and the effect of inflammatory response on plaque are not known. Currently, plaque stabilization is crucial for the prognosis of AS.

AIM OF THE STUDY

Our study mainly focused on the therapeutic effects of ZXYF on high-fat diet (HFD)-induced vascular inflammation and vulnerable plaques (VP) in mice and explored its underlying mechanism.

METHODS AND MATERIALS

Male apolipoprotein E knockout (APOE-/-) mice were fed HFD for 8 weeks to establish a VP model. During this period, the mice were also administered ZXYF, while atorvastatin (ATO) was used as a positive control. Aortic plaque area and morphology were detected by oil red staining and HE staining. Aortic plaque collagen content was detected by Masson staining. M1/M2 type macrophages were detected using immunofluorescence (IF). The study analyzed the levels of inflammation-related cytokines (IL-1β, IL-10, IL-6), MAPK/NF-κB pathway proteins, and NLRP3 inflammasomes (NLRP3, Caspase-1) using Western blot. Additionally, the levels of matrix metalloproteinase (MMP)-2 and MMP-9 and α-smooth muscle actin (α-SMA) in the aorta were analyzed using immunohistochemistry (IHC). The plaque instability index was calculated for each group using the vulnerable plaque formula.

RESULTS

In this study, APOE-/- mice were fed high-fat diet for 8 weeks. The results of oil-red and HE staining indicated a significant increase in the aortic plaque area of the mice, which exhibited a typical VP phenotype. ZXYF and ATO significantly improved AS plaques and prevented plaque rupture. HFD exacerbated vascular inflammation, stimulated macrophage conversion to M1-type through the MAPK/NF-κB signaling pathway, and released pro-inflammatory factors such as interleukin (IL)-1β, IL-1α, and IL-6. These factors activated NLRP3 inflammasome, leading to cellular death. However, ZXYF could reverse this trend and promote the conversion of macrophages to the anti-inflammatory M2 type. The anti-inflammatory effect of ATO was not significant. Moreover, HFD promoted the release of MMP-2 and MMP-9 from macrophages, which degraded plaque collagen, and induced a decrease in plaque SMC content, resulting in a thinning of the plaque fibrous cap. In contrast, ZXYF inhibited the decomposition of plaque collagen and increased the content of plaque smooth muscle cells (SMC) by reducing macrophage secretion of MMPs, thereby stabilizing plaques. Although ATO could reverse the decrease in plaque collagen and SMC content, its effect on MMPs was not significant. Finally, we calculated the vulnerability index to assess the overall risk of the plaque vulnerability phenotype. In line with these findings, ZXYF and ATO were able to effectively reverse the increase in the vulnerability index caused by HFD and lower the risk of adverse cardiovascular events.

CONCLUSION

Our results suggested that ZXYF could reduce inflammation and increase plaque stability by inhibiting the MAPK/NF-κB signaling pathway, which provided a theoretical basis for clinical application and subsequent research.

Zexieyin formula alleviates atherosclerosis with cognitive impairment: A novel role in the treatment of comorbidities and its underlying mechanisms

ETHNOPHARMACOLOGICAL RELEVANCY

Zexieyin formula (ZXYF) has been identified to have therapeutic actions of atherosclerosis (AS). It's unknown that whether ZXYF has therapeutic potential of atherosclerosis (AS) with cognitive impairment (CI) and its underlying mechanisms.

AIM OF THE STUDY

To elucidate therapeutic effect of ZXYF for AS with CI as well as its underlying mechanisms in AS with CI mice model.

METHODS AND MATERIALS

To establish AS with CI model, we fed ApoE-/- mice with high-fat diet (HFD) for 8 weeks. Oil red O staining (ORO) and Hematoxylin-eosin staining (HE) were used to detect aortic plaque area. Morris water maze (MWM) and Y-maze were used to measure cognitive function and cognitive improvement after administration of ZXYF and atorvastatin (ATO). Network pharmacology was used to screen for potential mechanisms for improving cognitive function. Western blot was used to detect expressions of MAPK, Aβ and synaptic proteins in hippocampus.

RESULTS

HFD caused and accelerated the AS in ApoE-/- mice, while it was easier able to produce CI than normal mice. Administration of ZXYF or ATO for 8 weeks significantly reduced aortic plaque area in ORO and HE tests, and improved cognitive abilities in MWM and Y-maze tests. Network pharmacology results showed that MAPK or synaptic proteins were highly associated with CI. HFD contributed to abnormal expressions of MAPK (pERK, pP38, pJNK), NF-kB, synaptic proteins (PSD95, synapsin1) and β-amyloid (Aβ) in hippocampus, which were all reversed by ZXYF. However, ERK and PSD95 expressions were not reversed by ATO in hippocampus.

CONCLUSIONS

ZXYF mitigated AS, further alleviating CI by modulating MAPK signaling, relating to synaptic proteins enhancing and Aβ protein decreasing in the hippocampus. This study firstly lit up the new clinical application of ZXYF, which might promote the use of ZXYF in AS and CI patients.

PI3K/AKT/SERBP-1 pathway regulates Alisma orientalis beverage treatment of atherosclerosis in APOE-/- high-fat diet mice

CONTEXT

Previously, we found Alisma orientalis beverage (AOB), a classic traditional Chinese medicine (TCM) formulation, had the potential effect of treating atherosclerosis (AS). The underlying mechanism was still unclear.

OBJECTIVE

As an extention of our previous work, to investigate the underlying mechanism of action of AOB in the treatment for AS.

MATERIALS AND METHODS

Network pharmacology was conducted using SwissTargetPrediction, GeneCards, DrugBank, Metascape, etc., to construct component-target-pathway networks. In vivo, AS models were induced by a high-fat diet (HFD) for 8 consecutive weeks in APOE^-/- mice. After the administration of AOB (3.8 g/kg, i.g.) for 8 weeks, we assessed the aortic plaque, four indicators of blood lipids, and expression of the PI3K/AKT/SREBP-1 pathway in liver.

RESULTS

Network pharmacology showed that PI3K/AKT/SREBP-1 played a role in AOB's treatment for AS (PI3K: degree = 18; AKT: degree = 17). Moreover, we found that the arterial plaque area and four indicators of blood lipids were all significantly reversed by AOB treatment in APOE^-/- mice fed with HFD (plaque area reduced by about 37.75%). In addition, phosphorylated expression of PI3K/AKT and expression of SREBP-1 were obviously increased in APOE^-/- mice fed with HFD, which were all improved by AOB (PI3K: 51.6%; AKT: 23.6%; SREBP-1: 40.0%).

CONCLUSIONS

AOB had therapeutic effects for AS by improving blood lipids and inhibition of the PI3K/AKT/SERBP-1 pathway in the liver. This study provides new ideas for the treatment of AS, as well as new evidence for the clinical application of AOB.

Gut microbiota and microbiota-derived metabolites in cardiovascular diseases

ABSTRACT

Cardiovascular diseases, including heart failure, coronary artery disease, atherosclerosis, aneurysm, thrombosis, and hypertension, are a great economic burden and threat to human health and are the major cause of death worldwide. Recently, researchers have begun to appreciate the role of microbial ecosystems within the human body in contributing to metabolic and cardiovascular disorders. Accumulating evidence has demonstrated that the gut microbiota is closely associated with the occurrence and development of cardiovascular diseases. The gut microbiota functions as an endocrine organ that secretes bioactive metabolites that participate in the maintenance of cardiovascular homeostasis, and their dysfunction can directly influence the progression of cardiovascular disease. This review summarizes the current literature demonstrating the role of the gut microbiota in the development of cardiovascular diseases. We also highlight the mechanism by which well-documented gut microbiota-derived metabolites, especially trimethylamine N-oxide, short-chain fatty acids, and phenylacetylglutamine, promote or inhibit the pathogenesis of cardiovascular diseases. We also discuss the therapeutic potential of altering the gut microbiota and microbiota-derived metabolites to improve or prevent cardiovascular diseases.

Gut Microbiota and Acylcarnitine Metabolites Connect the Beneficial Association between Estrogen and Lipid Metabolism Disorders in Ovariectomized Mice

Decreased estrogen level is one of the main causes of lipid metabolism disorders and coronary heart disease in women after menopause. Exogenous estradiol benzoate is effective to some extent in alleviating lipid metabolism disorders caused by estrogen deficiency. However, the role of gut microbes in the regulation process is not yet appreciated. The objective of this study was to investigate the effects of estradiol benzoate supplementation on lipid metabolism, gut microbiota, and metabolites in ovariectomized (OVX) mice and to reveal the importance of gut microbes and metabolites in the regulation of lipid metabolism disorders. This study found that high doses of estradiol benzoate supplementation effectively attenuated fat accumulation in OVX mice. There was a significant increase in the expression of genes enriched in hepatic cholesterol metabolism and a concomitant decrease in the expression of genes enriched in unsaturated fatty acid metabolism pathways. Further screening of the gut for characteristic metabolites associated with improved lipid metabolism revealed that estradiol benzoate supplementation influenced major subsets of acylcarnitine metabolites. Ovariectomy significantly increased the abundance of characteristic microbes that are significantly negatively associated with acylcarnitine synthesis, such as Lactobacillus and Eubacterium ruminantium group bacteria, while estradiol benzoate supplementation significantly increased the abundance of characteristic microbes that are significantly positively associated with acylcarnitine synthesis, such as Ileibacterium and Bifidobacterium spp. The use of pseudosterile mice with gut microbial deficiency greatly facilitated the synthesis of acylcarnitine due to estradiol benzoate supplementation and also alleviated lipid metabolism disorders to a greater extent in OVX mice. IMPORTANCE Our findings establish a role for gut microbes in the progression of estrogen deficiency-induced lipid metabolism disorders and reveal key target bacteria that may have the potential to regulate acylcarnitine synthesis. These findings suggest a possible route for the use of microbes or acylcarnitine to regulate disorders of lipid metabolism induced by estrogen deficiency.

ZeXieYin Formula alleviates TMAO-induced cognitive impairment by restoring synaptic plasticity damage

ETHNOPHARMACOLOGICAL RELEVANCE

Treating cognitive impairment is a challenging and necessary research topic. ZeXieYin Formula (ZXYF), is a traditional herbal formula documented in the book of HuangDiNeiJing. Our previous studies demonstrated the ameliorative effects of ZXYF on atherosclerosis by reducing the plasma trimethylamine oxide (TMAO) level. TMAO is a metabolite of gut microorganisms, our recent research found that the increasing level of TMAO may have adverse effects on cognitive functions.

AIM OF THE STUDY

Our study mainly focused on the therapeutic effects of ZXYF on TMAO-induced cognitive impairment in mice and explored its underlying mechanism.

MATERIALS AND METHODS

After the TMAO-induced cognitive impairment mice models were established, we applied behavioral tests to estimate the learning and memory ability of the ZXYF intervention mice. Liquid chromatography-mass spectrometry (LC-MS) was used to quantify the TMAO levels in plasma and the brain. The effects of ZXYF on the hippocampal synaptic structure and the neurons were observed by transmission electron microscopy (TEM) and Nissl staining. In addition, western-blotting (WB) and immunohistochemical (IHC) staining were used to detect the level of related proteins in the synaptic structure and further verify the changes in synaptic plasticity and the mTOR pathway after ZXYF administration.

RESULTS

Behavioral tests showed that the learning and memory ability of mice impaired after a period of TMAO intervention and ZXYF could alleviate these changes. A series of results showed that ZXYF partly restored the damage of hippocampal synapse and neurons in TMAO-induced mice, at the same time, the expression of synapse-related proteins and mTOR pathway-related proteins were significantly regulated compared with the damage caused by TMAO.

CONCLUSION

ZXYF could alleviate TMAO-induced cognitive impairment by improving synaptic function, reducing neuronal damage, regulating synapse-associated proteins, and regulating the mTOR signaling pathway.

The linkage of gut microbiota and the property theory of traditional Chinese medicine (TCM): Cold-natured and sweet-flavored TCMs as an example

ETHNOPHARMACOLOGICAL RELEVANCE

The property theory of traditional Chinese medicine (TCM) is a unique medical theory based on an extensive clinical practice for thousands of years, which guides TCM doctors choosing proper medicines to treat specific diseases. The nature and flavor of TCM are a high generalization of drug's characteristics according to the property theory. Despite intensive investigations, the modern interpretation of TCM property theory still confronts several challenges, which greatly hampers the elucidation of TCM's mechanisms as well as its application. Compelling evidence has proved that gut microbiota may be a potential indicator for TCM's efficacy and mechanism. Nevertheless, at present, the relationship between the gut microbiota and the nature and flavor of TCM has not been fully elucidated.

AIM OF THE STUDY

To fill the gap in this field, we developed a comprehensive study to investigate the relationship between gut microbial community and TCM's property.

MATERIALS AND METHODS

We searched "PubMed" and "China National Knowledge Infrastructure (CNKI)" with the key word "gut microbiota", and screened the published articles related to TCM. In this review, we mainly applied cold-natured and sweet-flavored TCMs as an example to explore the modulation of cold-natured and sweet-flavored TCMs on gut microbiota, and identify the potential relationship between the alterations of gut microbiota and TCM's efficacy.

RESULTS

We found cold-natured and sweet-flavored TCMs possess several pharmacological activities and generally enrich beneficial bacteria like Akkermansia, Bacteroides, Lactobacillus and Bifidobacterium, which is in good accordance with their pharmacological effects. Simultaneously, these TCMs reduce the relative abundance of some harmful bacteria belonging to Firmicutes (Streptpcoccus, Enterococcus, Turicibacter, Anaerostipes and Oscillibacter) and Proteobacteria (Helicobacter, Enterobacter, Sutterella, Klebsiella, Desulfovibrio, Escherichia coli and Campylobacter jejuni). These results indicate that there are some intrinsic correlations between gut microbiota and the property of TCM, and gut microbiota may serve as a potential indicator to reflect the property of TCM.

CONCLUSIONS

This pilot but comprehensive review provides an interesting proposal that the ancient theory of TCM property may be interpreted by the modern biological findings in gut microbiome.

Role of herbal medicine and gut microbiota in the prevention and treatment of obesity

ETHNOPHARMACOLOGICAL RELEVANCE

Obesity is a common metabolic dysfunction disease, which is highly correlated with the homeostasis of gut microbiota (GM). The dysregulation of GM on energy metabolism, immune response, insulin resistance and endogenous metabolites (e.g., short chain fatty acids and secondary bile acids) can affect the occurrence and development of obesity. Herbal medicine (HM) has particular advantages and definite therapeutic effects in the prevention and treatment of obesity, but its underlying mechanism is not fully clear.

AIM OF THE STUDY

In this review, the representative basic and clinical anti-obesity studies associated with the homeostasis of GM regulated by HM including active components, single herb and herbal formulae were summarized and discussed. We aim to provide a state of art reference for the mechanism research of HM in treating obesity and the further development of new anti-obesity drugs.

MATERIALS AND METHODS

The relevant information was collected by searching keywords (obesity, herbal medicine, prescriptions, mechanism, GM, short chain fatty acids, etc.) from scientific databases (CNKI, PubMed, SpringerLink, Web of Science, SciFinder, etc.).

RESULTS

GM dysbiosis did occur in obese patients and mice, whiles the intervention of GM could ameliorate the condition of obesity. HM (e.g., berberine, Ephedra sinica, Rehjnannia glutinosa, and Buzhong Yiqi prescription) has been proved to possess a certain regulation on GM and an explicit effect on obesity, but the exact mechanism of HM in improving obesity by regulating GM remains superficial.

CONCLUSION

GM is involved in HM against obesity, and GM can be a novel therapeutic target for treating obesity.

Dietary choline metabolite TMAO impairs cognitive function and induces hippocampal synaptic plasticity declining through the mTOR/P70S6K/4EBP1 pathway

Mild cognitive impairment (MCI) is an intermediate state between "healthy" and "dementia", which affects memory and cognitive function. Timely intervention and treatment of MCI can effectively prevent it from developing into an incurable neurodegenerative disease. Lifestyle factors, such as dietary habits, were highlighted as risk factors for MCI. The effect of a high-choline diet on cognitive function is contentious. In this study, we focus our attention on the choline metabolite trimethylamine-oxide (TMAO), an acknowledged pathogenic molecule of cardiovascular disease (CVD). With recent studies indicating that TMAO also plays a potential role in the central nervous system (CNS), we aim to explore the effect of TMAO on synaptic plasticity in the hippocampus, the basic structure of studying and memory. Using various hippocampal-dependent spatial references or working memory-related behavioral texts, we found that TMAO treatment caused both long-term memory (LTM) and short-term memory (STM) deficits in vivo. Simultaneously, the plasm and whole brain levels of choline and TMAO were measured by employing liquid phase mass spectrometry (LC/MS). Furthermore, the effects of TMAO on the hippocampus were further explored by applying Nissl staining and transmission electron microscopy (TEM). Moreover, the expression of synaptic plasticity-related proteins, including synaptophysin (SYN), postsynaptic density protein95 (PSD95), and N-methyl-aspartate receptor (NMDAR), was examined by western blotting and immunohistochemical (IHC). The results showed that TMAO treatment contributes to neuron loss, synapse ultrastructure alteration, and synaptic plasticity impairments. In mechanism, the mammalian target of rapamycin (mTOR) regulates synaptic function, and the activation of the mTOR signaling pathway was observed in TMAO groups. In conclusion, this study confirmed that the choline metabolite TMAO can induce hippocampal-dependent learning and memory ability impairment with synaptic plasticity deficits by activating the mTOR signaling pathway. The effects of choline metabolites on cognitive function may provide a theoretical basis for establishing the daily reference intakes (DRIs) of choline.

Dietary Methionine Restriction Alleviates Choline-Induced Tri-Methylamine-N-Oxide (TMAO) Elevation by Manipulating Gut Microbiota in Mice

Dietary methionine restriction (MR) has been shown to decrease plasma trimethylamine-N-oxide (TMAO) levels in high-fat diet mice; however, the specific mechanism used is unknown. We speculated that the underlying mechanism is related with the gut microbiota, and this study aimed to confirm the hypothesis. In this study, we initially carried out an in vitro fermentation experiment and found that MR could reduce the ability of gut microbiota found in the contents of healthy mice and the feces of healthy humans to produce trimethylamine (TMA). Subsequently, mice were fed a normal diet (CON, 0.20% choline + 0.86% methionine), high-choline diet (H-CHO, 1.20% choline + 0.86% methionine), or high-choline + methionine-restricted diet (H-CHO+MR, 1.20% choline + 0.17% methionine) for 3 months. Our results revealed that MR decreased plasma TMA and TMAO levels in H-CHO-diet-fed mice without changing hepatic FMO3 gene expression and enzyme activity, significantly decreased TMA levels and expression of choline TMA-lyase (CutC) and its activator CutD, and decreased CutC activity in the intestine. Moreover, MR significantly decreased the abundance of TMA-producing bacteria, including Escherichia-Shigella (Proteobacteria phylum) and Anaerococcus (Firmicutes phylum), and significantly increased the abundance of short-chain fatty acid (SCFA)-producing bacteria and SCFA levels. Furthermore, both MR and sodium butyrate supplementation significantly inhibited bacterial growth, down-regulated CutC gene expression levels in TMA-producing bacteria, including Escherichia fergusonii ATCC 35469 and Anaerococcus hydrogenalis DSM 7454 and decreased TMA production from bacterial growth under in vitro anaerobic fermentation conditions. In conclusion, dietary MR alleviates choline-induced TMAO elevation by manipulating gut microbiota in mice and may be a promising approach to reducing circulating TMAO levels and TMAO-induced atherosclerosis.

The role of the gut microbiota in health and cardiovascular diseases

The gut microbiota is critical to human health, such as digesting nutrients, forming the intestinal epithelial barrier, regulating immune function, producing vitamins and hormones, and producing metabolites to interact with the host. Meanwhile, increasing evidence indicates that the gut microbiota has a strong correlation with the occurrence, progression and treatment of cardiovascular diseases (CVDs). In patients with CVDs and corresponding risk factors, the composition and ratio of gut microbiota have significant differences compared with their healthy counterparts. Therefore, gut microbiota dysbiosis, gut microbiota-generated metabolites, and the related signaling pathway may serve as explanations for some of the mechanisms about the occurrence and development of CVDs. Several studies have also demonstrated that many traditional and latest therapeutic treatments of CVDs are associated with the gut microbiota and its generated metabolites and related signaling pathways. Given that information, we summarized the latest advances in the current research regarding the effect of gut microbiota on health, the main cardiovascular risk factors, and CVDs, highlighted the roles and mechanisms of several metabolites, and introduced corresponding promising treatments for CVDs regarding the gut microbiota. Therefore, this review mainly focuses on exploring the role of gut microbiota related metabolites and their therapeutic potential in CVDs, which may eventually provide better solutions in the development of therapeutic treatment as well as the prevention of CVDs.

High fat diet-induced hyperlipidemia and tissue steatosis in rabbits through modulating ileal microbiota

High-fat diet (HFD) and overnutrition are important starting factors that may alter intestinal microbiota, lipid metabolism, and systemic inflammation. However, there were few studies on how intestinal microbiota contributes to tissue steatosis and hyperlipidemia. Here, we investigated the effect of lipid metabolism disorder-induced inflammation via toll-like receptor 2 (TLR-2), toll-like receptor 4 (TLR-4), and nuclear factor-κB (NF-κB) pathways at the intestinal level in response to HFD. Twenty 80-day-old male New Zealand White rabbits were randomly divided into the normal diet group (NDG) and the high-fat diet group (HDG) for 80 days. Growth performance, blood biochemical parameters, lipid metabolism, inflammation, degree of tissue steatosis, and intestinal microbial composition were measured. HFD increased the relative abundance of Christensenellaceae_R_7_group, Marvinbryantia, Akkermansia etc., with a reduced relative abundance of Enterorhabdus and Lactobacillus. Moreover, HFD caused steatosis in the liver and abdominal fat and abnormal expression of some genes related to lipid metabolism and tight junction proteins. The TLR-2, TLR-4, NF-κB, TNF-α, and IL-6 were confirmed by overexpression with downregulation of IL-10. Serum biochemical indices (TG, TCHO, LDL-C, and HDL-C) were also increased, indicating evidence for the development of the hyperlipidemia model. Correlation analysis showed that this microbial dysbiosis was correlated with lipid metabolism and inflammation, which were associated with the intestinal tract's barrier function and hyperlipidemia. These results provide an insight into the relationship between HFD, the intestinal microbiota, intestinal barrier, tissue inflammation, lipid metabolism, and hyperlipidemia. KEY POINTS: • High-fat diet leads to ileal microbiota disorders • Ileal microbiota mediates local and systemic lipid metabolism disorders and inflammation • There is a specific link between ileal microbiota, histopathology, and hyperlipidemia.

Therapeutic potential of traditional Chinese medicine against atherosclerosis: Targeting trimethylamine N-oxide

BACKGROUND

Recent studies have shown that plasma trimethylamine-N-oxide (TMAO) level is highly correlated with the risk of atherosclerosis (AS), and the elevated level is significantly positively correlated with the incidence of AS.

PURPOSE

The purpose of this article is to offer a useful summary of the correlation between TMAO and AS, and the effect of herbal monomers, herbal extracts, and formulas on anti-atherosclerosis mediated by TMAO.

METHOD

The data contained in this article comes from PubMed, Web of Science, and China National Knowledge Infrastructure.

RESULTS

This review discusses the main mechanism of AS induced by TMAO, including endothelial dysfunction, macrophage foaming, platelet reactivity, and cholesterol metabolism, and summarizes 6 herb monomers, 5 herb extracts, and 2 formulas that have been tested for their anti-TMAO activity.

CONCLUSION

The current understanding of possible ways to reduce TMAO generation is discussed, with the effect and potential of herb monomers, herb extracts, and formulas highlighted.

Pharmacological Properties and Molecular Targets of Alisol Triterpenoids from Alismatis Rhizoma

More than 100 protostane triterpenoids have been isolated from the dried rhizomes of Alisma species, designated Alismatis rhizoma (AR), commonly used in Asian traditional medicine to treat inflammatory and vascular diseases. The main products are the alisols, with the lead compounds alisol-A/-B and their acetate derivatives being the most abundant products in the plant and the best-known bioactive products. The pharmacological effects of Ali-A, Ali-A 24-acetate, Ali-B, Ali-B 23-acetate, and derivatives have been analyzed to provide an overview of the medicinal properties, signaling pathways, and molecular targets at the origin of those activities. Diverse protein targets have been proposed for these natural products, including the farnesoid X receptor, soluble epoxide hydrolase, and other enzymes (AMPK, HCE-2) and functional proteins (YAP, LXR) at the origin of the anti-atherosclerosis, anti-inflammatory, antioxidant, anti-fibrotic, and anti-proliferative activities. Activities were classified in two groups. The lipid-lowering and anti-atherosclerosis effects benefit from robust in vitro and in vivo data (group 1). The anticancer effects of alisols have been largely reported, but, essentially, studies using tumor cell lines and solid in vivo data are lacking (group 2). The survey shed light on the pharmacological properties of alisol triterpenoids frequently found in traditional phytomedicines.

Targeting Trimethylamine N-Oxide: A New Therapeutic Strategy for Alleviating Atherosclerosis

Atherosclerosis (AS) is one of the most common cardiovascular diseases (CVDs), and there is currently no effective drug to reverse its pathogenesis. Trimethylamine N-oxide (TMAO) is a metabolite of the gut flora with the potential to act as a new risk factor for CVD. Many studies have shown that TMAO is involved in the occurrence and development of atherosclerotic diseases through various mechanisms; however, the targeted therapy for TMAO remains controversial. This article summarizes the vital progress made in relation to evaluations on TMAO and AS in recent years and highlights novel probable approaches for the prevention and treatment of AS.

Platelets inhibit development of atherosclerosis in atherosclerotic mice

Platelets can protect from lipopolysaccharide-induced septic shock by inhibiting inflammation, but it is unknown whether platelets have an anti-atherosclerotic effect. The aim of this study was to investigate the effect of platelet transfusion on atherosclerosis (AS) in a mouse model of AS. Apolipoprotein E deficiency (ApoE^-/-) mice were fed with a high-fat diet (HFD) for 8 weeks to establish a mouse model of AS. Mice weekly underwent bi-weekly injection with or without platelets during AS induction (HFD+platelet). Hematoxylin-eosin (H&E), Oil Red O, and Sudan IV stainings were used to assess pathological and morphological changes in the aortic tissue. Lipid levels, and liver and kidney function were examined using an automatic biochemical analyzer. Immune histochemical assays were used to detect the infiltration and distribution of inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β), IL-6, and monocyte chemotactic protein-1 (MCP-1) in the aortic arch. Western blot and enzyme-linked immunosorbent assay (ELISA) were used to examine the expression levels of TNF-α, IL-1β, IL-6, and MCP-1 in the aorta or the peripheral blood, respectively. Compared with the HFD group, AS pathological lesions from the aortic arch in the HFD+platelet group were significantly smaller and alterations in the lipid metabolism were also less pronounced. Furthermore, TNF-α, IL-1β, IL-6, and MCP-1 levels were all significantly reduced in mice that received platelet injection. Platelets transfusion can effectively ameliorate lipid metabolism, suppress the inflammatory response in the vascular wall, and inhibit the development of AS in mice.

Gut Metabolite Trimethylamine-N-Oxide in Atherosclerosis: From Mechanism to Therapy

Atherosclerosis is associated with various pathological manifestations, such as ischemic heart disease, ischemic stroke, and peripheral arterial disease, and remains a leading cause of public health concern. Atherosclerosis is an inflammatory disease characterized by endothelial dysfunction; vascular inflammation; and the deposition of lipids, cholesterol, calcium, and cellular debris within the vessel wall intima. In-depth studies of gut flora in recent years have shown that bacterial translocation and the existence of bacterial active products in blood circulation can affect the inflammatory state of the whole blood vessel. The gut flora is considered to be a large “secretory organ,” which produces trimethylamine-N-oxide (TMAO), short-chain fatty acids and secondary bile acids by breaking down the ingested food. Studies have shown that TMAO is an independent risk factor for the occurrence of malignant adverse cardiovascular events, but whether it is harmful or beneficial to patients with cardiovascular diseases with mild or no clinical manifestations remains controversial. We review the relationship between TMAO and its precursor (L-carnitine) and coronary atherosclerosis and summarize the potential molecular mechanism and therapeutic measures of TMAO on coronary atherosclerosis.

Paeonol Attenuated Vascular Fibrosis Through Regulating Treg/Th17 Balance in a Gut Microbiota-Dependent Manner

Background: Paeonol (Pae) is a natural phenolic compound isolated from Cortex Moutan, which exhibits anti-atherosclerosis (AS) effects. Our previous work demonstrated that gut microbiota plays an important role during AS treatment as it affects the efficacy of Pae. However, the mechanism of Pae in protecting against vascular fibrosis as related to gut microbiota has yet to be elucidated. Objective: To investigate the antifibrosis effect of Pae on AS mice and demonstrate the underlying gut microbiota-dependent mechanism. Methods: ApoE^-/- mice were fed with high-fat diet (HFD) to replicate the AS model. H&E and Masson staining were used to observe the plaque formation and collagen deposition. Short-chain fatty acid (SCFA) production was analyzed through LC-MS/MS. The frequency of immune cells in spleen was phenotyped by flow cytometry. The mRNA expression of aortic inflammatory cytokines was detected by qRT-PCR. The protein expression of LOX and fibrosis-related indicators were examined by western blot. Results: Pae restricted the development of AS and collagen deposition. Notably, the antifibrosis effect of Pae was achieved by regulating the gut microbiota. LC-MS/MS data indicated that the level of SCFAs was increased in caecum contents. Additionally, Pae administration selectively upregulated the frequency of regulatory T (Treg) cells as well as downregulated the ratio of T helper type 17 (Th17) cells in the spleen of AS mice, improving the Treg/Th17 balance. In addition, as expected, Pae intervention can significantly downregulate the levels of proinflammatory cytokines IL-1β, IL-6, TNF-α, and IL-17 in the aorta, and upregulate the levels of anti-inflammatory factor IL-10, a marker of Treg cells. Finally, Pae's intervention in the gut microbiota resulted in the restoration of the balance of Treg/Th17, which indirectly downregulated the protein expression level of LOX and fibrosis-related indicators (MMP-2/9 and collagen I/III). Conclusion: Pae attenuated vascular fibrosis in a gut microbiota-dependent manner. The underlying protective mechanism was associated with the improved Treg/Th17 balance in spleen mediated through the increased microbiota-derived SCFA production. Collectively, our results demonstrated the role of Pae as a potential gut microbiota modulator to prevent and treat AS.

Trimethylamine-N-Oxide Pathway: A Potential Target for the Treatment of MAFLD

Trimethylamine-N-oxide (TMAO) is a molecular metabolite derived from the gut flora, which has recently emerged as a candidate risk factor for metabolic dysfunction-associated fatty liver disease (MAFLD). TMAO is mainly derived from gut, where the gut microbiota converts TMA precursors into TMA, which is absorbed into the bloodstream through the intestinal mucosa, and then transformed into TMAO by hepatic flavin monooxygenases (FMOs) in the liver. High-nutrient diets rich in TMA precursors, such as red meat, eggs, and fish, are the main sources of TMAO. Excessively consuming such diets not only directly affects energy metabolism in liver, but also increases the concentration of TMAO in plasma, which promotes the development of MAFLD by affecting bile acid metabolism, unfolded protein response, and oxidative stress. In this review, we focused on the relationship between TMAO and MAFLD and summarized intervention strategies for reducing circulating TMAO concentration, aiming at providing new targets for the prevention and treatment of MAFLD.

NEIL3-deficiency increases gut permeability and contributes to a pro-atherogenic metabolic phenotype

Atherosclerosis and its consequences cause considerable morbidity and mortality world-wide. We have previously shown that expression of the DNA glycosylase NEIL3 is regulated in human atherosclerotic plaques, and that NEIL3-deficiency enhances atherogenesis in Apoe-/- mice. Herein, we identified a time point prior to quantifiable differences in atherosclerosis between Apoe-/-Neil3-/- mice and Apoe-/- mice. Mice at this age were selected to explore the metabolic and pathophysiological processes preceding extensive atherogenesis in NEIL3-deficient mice. Untargeted metabolomic analysis of young Apoe-/-Neil3-/- mice revealed significant metabolic disturbances as compared to mice expressing NEIL3, particularly in metabolites dependent on the gut microbiota. 16S rRNA gene sequencing of fecal bacterial DNA indeed confirmed that the NEIL3-deficient mice had altered gut microbiota, as well as increased circulating levels of the bacterially derived molecule LPS. The mice were challenged with a FITC-conjugated dextran to explore gut permeability, which was significantly increased in the NEIL3-deficient mice. Further, immunohistochemistry showed increased levels of the proliferation marker Ki67 in the colonic epithelium of NEIL3-deficient mice, suggesting increased proliferation of intestinal cells and gut leakage. We suggest that these metabolic alterations serve as drivers of atherosclerosis in NEIL3-deficient mice.

Mechanisms of traditional Chinese medicine in modulating gut microbiota metabolites-mediated lipid metabolism

ETHNOPHARMACOLOGICAL RELEVANCE

The gut microbiome plays an important role in advancing the process of host lipid metabolism directly or indirectly. Traditional Chinese medicine (TCM) can improve the intestinal environment by intervening with gut microbiota metabolites to potentially regulate lipid levels. However, the underlying mechanisms remain unclear. Therefore, we examined the current databases to search for studies related to influence of TCM on the gut microbiota metabolites-mediated lipid metabolism.

AIM OF THE STUDY

This paper aims to review the TCM that could regulate lipid metabolism mediated by microbial metabolites and their pharmacological targets and provides perspectives for future investigation.

METHODS

Electronic databases including PubMed, Web of Science, EMBASE, the Cochrane Library, Chinese Biological Medicine Database, and China National Knowledge Infrastructure were searched up to April 2021 to identify eligible studies.

RESULTS

A total of 30 active compounds, five Chinese herbal formulae, and three proprietary Chinese medicines were included in this review. We found that TCM can effectively improve lipid metabolism by increasing short chain fatty acids (SCFA) levels, regulating bile acid (BA) metabolism, reducing the production of trimethylamine N-oxide (TMAO), alleviating the release of inflammatory factors, and altering branched-chain amino acids (BCAA) biosynthesis. This process is accompanied by changes in the structure of the gut microbiota, blood lipids, and expression of lipid metabolism genes.

CONCLUSION

In summary, studies on the regulation of lipid metabolism by microbial metabolites in TCM will provide a new approach for better management of dyslipidemia, which may facilitate future clinical treatments.

Lifelong dietary omega-3 fatty acid suppresses thrombotic potential through gut microbiota alteration in aged mice

Aging is a major risk factor for cardiovascular diseases, including thrombotic events. The gut microbiota has been implicated in the development of thrombotic risk. Plant-derived omega-3 fatty acid ɑ-linolenic acid (ALA) confers beneficial anti-platelet and anti-inflammatory effects. Hence, antithrombotic activity elicited by ALA may be partly dependent on its interaction with gut microbiota during aging. Here, we demonstrate that lifelong dietary ALA decreases platelet hyperresponsiveness and thrombus formation in aged mice. These phenotypic changes can be partly attributed to alteration of microbial composition and reduction of its metabolite trimethylamine N-oxide and inflammatory mediators including TNF-α, as well as the upregulated production of short-chain fatty acid acetate. ALA-rich diet also dampens secretion of increased procoagulant factors, tissue factor and plasminogen activator inhibitor-1, in aged mice. Our results suggest long-term ALA supplementation as an attractive, accessible, and well-tolerated nutritional strategy against age-associated platelet hyperreactivity and thrombotic potential.

Jianpi Jieyu Decoction, An Empirical Herbal Formula, Exerts Psychotropic Effects in Association With Modulation of Gut Microbial Diversity and GABA Activity

Background: Recent studies suggest that gut microbiota was associated with the bidirectional gut-brain axis which could modulate neuropsychological functions of the central nervous system. Gut microbiota could produce gamma aminobutyric acid (GABA) that could modulate the gut-brain axis response. Jianpi Jieyu (JPJY) decoction, a traditional Chinese formula, is mainly composed of Astragalus membranaxeus and Radix Pseudostellariae. Although the JPJY decoction has been used to treat the depression in China, the potential action of its antidepressant has not been well understood. Thus this study was aim to investigate the role of JPJY improve gut microbiota homeostasis in the chronic stress induced depressive mice. Methods: The antidepressant effect of JPJY on chronic unpredictable mild stress (CUMS) mice was evaluated by using sucrose preference test, tail suspension test and forced swim test. Fatigue-like behaviors were evaluated using degree of redness, grip strength test, and exhaustive swimming test. The new object recognition test was used to evaluate cognition performance. Fecal samples were collected and taxonomical analysis of intestinal microbial distribution was conducted with 16S rDNA. Serum level of GABA was measured using high performance liquid chromatography (HPLC). The expression of GluR1 and p-Tau protein in the hippocampus was determined using Western blotting. Results: The dose of 9.2 g/kg JPJY produced antidepressant-like effects. JPJY and its major components also modulated gut microbiota diversity in the CUMS mice. Serum level of GABA and the expressions of hippocampal GluR1 and p-Tau were reversed after the administration of JPJY in CUMS mice. Conclusion: JPJY regulates gut microbiota to produce antidepressant-like effect and improve cognition deficit in depressive mice while its molecular mechanism possibly be enhanced NR1 and Tau expression in hippocampus and increased GABA in serum.

Regulatory effect of traditional Chinese medicine on gut microbiota in patients with atherosclerosis: A protocol for systematic review and meta-analysis

BACKGROUND

Atherosclerosis is the pathological basis of many cardiovascular and cerebrovascular diseases, and its pathogenesis is complex. Recent studies revealed a significant role of gut microbiota in the onset and development of atherosclerosis. Traditional Chinese medicine has rich clinical experience and unique advantages in the treatment of atherosclerosis. A large number of studies have proved that traditional Chinese medicine has the functions of reducing blood lipid, regulating gut microbiota, and resisting inflammation. The aim of this systematic review is to observe the randomized controlled trial of traditional Chinese medicine in treating gut microbiota, so as to evaluate the effectiveness and safety of traditional Chinese medicine in treating atherosclerosis patients.

METHODS

The English database (PubMed, Web of Science, Embase, the Cochrane Library) and Chinese database (China National Knowledge Infrastructure, the Chongqing VIP Chinese Science, and Technology Periodic Database, Wanfang Database, and China Biomedical Literature Database) will be searched up to October 2020. We will also manually search the Chinese clinical trial register, conference papers, and unpublished studies or references. Randomized control trials of traditional Chinese medicine treatment of atherosclerosis were collected comprehensively, and 2 researchers will independently screen literature, data extraction, and evaluation the quality of literature methodology. The primary outcomes are lipid metabolism and gut microbiota and their metabolites. The secondary outcomes are the change of inflammatory markers. Meta-analysis was performed by RevMan 5.3.5 software. The Grades of Recommendation, Assessment, Development, and Evaluation will be used to evaluate the outcome quality of evidence.

RESULTS

This study will comprehensively review the existing evidence of traditional Chinese medicine in treating atherosclerosis from the perspective of gut microbiota.

CONCLUSION

This study will provide information on the effectiveness and safety of traditional Chinese medicine in treating atherosclerosis from the perspective of gut microbiota.

UNIQUE INPLASY NUMBER

INPLASY2020110056.