Modulation of atherosclerosis-related signaling pathways by Chinese herbal extracts: Recent evidence and perspectives

Atherosclerotic cardiovascular disease remains a preeminent cause of morbidity and mortality globally. The onset of atherosclerosis underpins the emergence of ischemic cardiovascular diseases, including coronary heart disease (CHD). Its pathogenesis entails multiple factors such as inflammation, oxidative stress, apoptosis, vascular endothelial damage, foam cell formation, and platelet activation. Furthermore, it triggers the activation of diverse signaling pathways including Phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt), NF-E2-related factor 2/antioxidant response element (Nrf2/ARE), the Notch signaling pathway, peroxisome proliferator-activated receptor (PPAR), nucleotide oligo-structural domain-like receptor thermoprotein structural domain-associated protein 3 (NLRP3), silencing information regulator 2-associated enzyme 1 (Sirt1), nuclear transcription factor-κB (NF-κB), Circular RNA (Circ RNA), MicroRNA (mi RNA), Transforming growth factor-β (TGF-β), and Janus kinase-signal transducer and activator of transcription (JAK/STAT). Over recent decades, therapeutic approaches for atherosclerosis have been dominated by the utilization of high-intensity statins to reduce lipid levels, despite significant adverse effects. Consequently, there is a growing interest in the development of safer and more efficacious drugs and therapeutic modalities. Traditional Chinese medicine (TCM) offers a vital strategy for the prevention and treatment of cardiovascular diseases. Numerous studies have detailed the mechanisms through which TCM active ingredients modulate signaling molecules and influence the atherosclerotic process. This article reviews the signaling pathways implicated in the pathogenesis of atherosclerosis and the advancements in research on TCM extracts for prevention and treatment, drawing on original articles from various databases including Google Scholar, Medline, CNKI, Scopus, and Pubmed. The objective is to furnish a reference for the clinical management of cardiovascular diseases.

In vitro immune-depression and anti-inflammatory activities of cantharidin on gilthead seabream (Sparus aurata) leucocytes activated by λ-carrageenan

Cantharidin is a natural compound with known therapeutic applications in humans. The aim of this study was to investigate the in vitro effects of cantharidin on gilthead seabream (Sparus aurata) head kidney leucocytes (HKL) stimulated with λ-carrageenan. HKLs were incubated for 24 h with cantharidin (0, 2.5 and 5 μg mL-1) and λ-carrageenan (0 and 1000 μg mL-1). The results showed that HKL viability only decreased by 15.2% after incubated with 5 μg mL-1 of cantharidin and λ-carrageenan. Cantharidin increased the peroxidase activity of HKLs only when incubated in combination with λ-carrageenan. Besides this, cantharidin inhibited the respiratory burst and phagocytic activities. Furthermore, cantharidin induced morphological changes in HKLs (apoptotic and vacuolization signs) that were enhanced when incubated with λ-carrageenan. Considering the analysis of the selected gene expression studied in HKLs [NF-κB subunits (rela, relb, crel, nfkb1, nfkb2), proinflammatory cytokines (il1b, tnfa), anti-inflammatory cytokines (il10, tgfb) and caspases (casp1, casp3, casp8, casp9)], although λ-carrageenan up-regulated the expression of the proinflammatory gene il1b, λ-carrageenan and cantharidin down-regulated its expression in HKLs. In addition, cantharidin up-regulated casp3 and casp9 expression. The casp3 and casp9 gene expression was down-regulated while casp1 gene expression was up-regulated in HKLs incubated with both cantharidin and λ-carrageenan. All the effects of cantharidin are related to its inhibitory effect on protein phosphatases, which induce apoptosis at long exposure times, and minimize the effects of λ-carrageenan. The present results provide detailed insight into the immune-depressive and anti-inflammatory properties of cantharidin on immune cells, which could be of interest to the aquaculture sector.

Cantharidin analogue alleviates dextran sulfate sodium-induced colitis in mice by inhibiting the activation of NF-κB signaling

Ulcerative colitis is a chronic inflammatory disease with a remitting-relapsing clinical course, it has evolved into a global burden given its high incidence worldwide. Cantharidin (CTD) derivatives are a class of compounds whose structures characterized with a 7-oxabicyclo [2.2.1]heptane core. Though potent cytotoxicity CTD and its derivatives showed, their clinical usage as anti-cancer drugs was limited by the toxicity in organs. In order to find new CTD analogues with good activity and lower toxicity, 21 CTD analogues with or without alkynyl substitution at C5 position of 7-oxabicyclo [2.2.1]heptane core were synthesized, some compounds showed better in vitro anti-inflammatory activity compared to CTD and norcantharidin (NCTD). Based on the structure-activity relationship results of in vitro experiment, analogue 3i was chosen for further study. Results from the acute toxicity in mice showed that 3i was hypotoxic with the single-dose MTD (maximum tolerated dose) for oral administration is over 1852 mg/kg, at least 35-fold lower than that of NCTD. Mechanism study indicated that 3i could potently inhibit TNF-α induced activation of NF-κB signaling by down-regulation the expression levels of phosphor- IKK, IκBα, and NF-κB p65, and alleviated dextran sulfate sodium-induced colitis in mice. This study indicated that CTD analogues with alkynyl substitution at C5 position of 7-oxabicyclo [2.2.1]heptane core is a kind of new compounds with good anti-inflammatory activity and lower toxicity in vivo, and might be used as therapeutic agents for inflammatory diseases.

The innate immune sensor STING accelerates neointima formation via NF-κB signaling pathway

Vascular smooth muscle cells (VSMCs) proliferation, migration, and phenotypic switching are considered crucial events in the progression of neointima formation. Stimulator of interferon genes (STING), an innate immune sensor of cyclic dinucleotides against pathogens, in neointima formation remains obscure. Here, we observed a significant increase in STING expression on the neointima of injured vessels and mouse aortic VSMCs induced by PDGF-BB. In vivo, global knockout of STING (Sting-/-) attenuated neointima formation after vascular injury. In vitro data showed that STING deficiency significantly alleviated PDGF-BB-induced proliferation and migration in VSMCs. Furthermore, these contractile marker genes were upregulated in Sting-/- VSMCs. Overexpression of STING promoted proliferation, migration, and phenotypic switching in VSMCs. Mechanistically, STING-NF-κB signaling was involved in this process. The pharmacological inhibition of STING induced by C-176 partially prevented neointima formation due to suppression of VSMCs proliferation. Taken together, STING-NF-κB axis significantly promoted proliferation, migration, and phenotypic switching of VSMCs, which may be a novel therapeutic approach to combat vascular proliferative diseases.

Tribulus terrestris L. extract ameliorates atherosclerosis by inhibition of vascular smooth muscle cell proliferation in ApoE-/- mice and A7r5 cells via suppression of Akt/MEK/ERK signaling

ETHNOPHARMACOLOGICAL RELEVANCE

Atherosclerosis (AS) is one of major threatens of death worldwide, and vascular smooth muscle cell (VSMC) proliferation is an important characteristic in the progression of AS. Tribulus terrestris L. is a well-known Chinese Materia Medica for treating skin pruritus, vertigo and cardiovascular diseases in traditional Chinese medicine. However, its anti-AS activity and inhibition effect on VSMC proliferation are not fully elucidated.

AIMS

We hypothesize that the furostanol saponins enriched extract (FSEE) of T. terrestris L. presents anti-AS effect by inhibition of VSMC proliferation. The molecular action mechanism underlying the anti-VSMC proliferation effect of FSEE is also investigated.

MATERIALS AND METHODS

Apolipoprotein-E deficient (ApoE^-/-) mice and rat thoracic smooth muscle cell A7r5 were employed as the in vivo and in vitro models respectively to evaluate the anti- AS and VSMC proliferation effects of FSEE. In ApoE^-/- mice, the amounts of total cholesterol, triglyceride, low density lipoprotein and high density lipoprotein in serum were measured by commercially available kits. The size of atherosclerotic plaque was observed by hematoxylin & eosin staining. The protein expressions of α-smooth muscle actin (α-SMA) and osteopontin (OPN) in the plaque were examined by immunohistochemistry. In A7r5 cells, the cell viability and proliferation were tested by MTT and Real Time Cell Analysis assays. The cell migration was evaluated by wound healing assay. Propidium iodide staining followed by flow cytometry was used to analyze the cell cycle progression. The expression of intracellular total and phosphorylated proteins including protein kinase B (Akt) and mitogen-activated protein kinases (MAPKs), such as mitogen-activated extracellular signal-regulated kinase (MEK), extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK), were detected by western blotting analysis.

RESULTS

FSEE significantly reduced the area of atherosclerotic plaque in high-fat diet-fed ApoE^-/- mice. And FSEE increased the protein expression level of α-SMA and decreased the level of OPN in atherosclerotic plaque, which revealed the inhibition of VSMC phenotype switching and proliferation. In A7r5 cells, FSEE suppressed fetal bovine serum (FBS) or oxidized low density lipoprotein (oxLDL)-triggered VSMC proliferation and migration in a concentration dependent manner. FSEE protected against the elevation of cell numbers in S phase induced by FBS or oxLDL and the reduction of cell numbers in G₀/G₁ phase induced by oxLDL. Moreover, the phosphorylation of Akt and MAPKs including MEK, ERK and JNK could be facilitated by FBS or oxLDL, while co-treatment of FSEE attenuated the phosphorylation of Akt induced by oxLDL as well as the phosphorylation of MEK and ERK induced by FBS. In addition, (25R)-terrestrinin B (JL-6), which was the main ingredient of FSEE, and its potential active pharmaceutical ingredients tigogenin (Tigo) and hecogenin (Heco) also significantly attenuated FBS or oxLDL-induced VSMC proliferation in A7r5 cells.

CONCLUSION

FSEE presents potent anti- AS and VSMC proliferation activities and the underlying mechanism is likely to the suppression of Akt/MEK/ERK signaling. The active components of FSEE are JL-6 and its potential active pharmaceutical ingredients Tigo and Heco. So, FSEE and its active compounds may be potential therapeutic drug candidates for AS.

Downregulation of P300/CBP-Associated Factor Protects from Vascular Aging via Nrf2 Signal Pathway Activation

Increasing evidence has shown that vascular aging has a key role in the pathogenesis of vascular diseases. P300/CBP-associated factor (PCAF) is involved in many vascular pathological processes, but the role of PCAF in vascular aging is unknown. This study aims to explore the role and underlying mechanism of PCAF in vascular aging. The results demonstrated that the expression of PCAF was associated with age and aging, and remarkably increased expression of PCAF was present in human atherosclerotic coronary artery. Downregulation of PCAF could reduce angiotensin II (AngII)-induced senescence of rat aortic endothelial cells (ECs) in vitro. In addition, inhibition of PCAF with garcinol alleviated AngII-induced vascular senescence phenotype in mice. Downregulation of PCAF could alleviate AngII-induced oxidative stress injury in ECs and vascular tissue. Moreover, PCAF and nuclear factor erythroid-2-related factor 2 (Nrf2) could interact directly, and downregulation of PCAF alleviated vascular aging by promoting the activation of Nrf2 and enhancing the expression of its downstream anti-aging factors. The silencing of Nrf2 with small interfering RNA attenuated the protective effect of PCAF downregulation from vascular aging. These findings indicate that downregulation of PCAF alleviates oxidative stress by activating the Nrf2 signaling pathway and ultimately inhibits vascular aging. Thus, PCAF may be a promising target for aging-related cardiovascular disease.

In vitro effects of cantharidin on gilthead seabream (Sparus aurata) head-kidney leucocytes

Cantharidin is a toxic vesicant terpene used in folk and traditional medicine due to its various therapeutic effects. Since there are no previous data on the effect of cantharidin in fish, this study aimed to investigate the in vitro related-inflammatory effects of cantharidin in gilthead seabream (Sparus aurata L.) head-kidney leucocytes (HKLs). In the first experiment, the HKLs were incubated with 0, 5 and 10 μg mL^-1 of cantharidin for 24 h to delimit its possible toxic effects. In a second experiment, leucocytes were incubated with ranging concentrations from 0 to 10 μg mL^-1 for 3, 6, or 12 h. Cell viability was higher in acidophilic granulocytes than in monocytes/macrophages and lymphocytes. Cantharidin caused apoptosis as was evidenced by transmission electron microscopy. In addition, cantharidin produced a time- and dose-dependent decrease of respiratory burst and phagocytic activities in HKLs, while their peroxidase activity was increased at 24 h of incubation with 5 and 10 μg mL^-1 of cantharidin. Different changes in the gene expression were observed after incubation with cantharidin. While the gene expression of tnfa, il1b and crel was up-regulated in HKLs, the nfkb1 and igmh genes were down-regulated in comparison to the expression found in control HKLs. Present results offer a first view of the possible effects and action mechanisms of cantharidin in HKLs, as well as its implication in the inflammatory process, which could be of interest not only for basic research but also in the aquaculture sector.

Value of M2BP in predicting in‐stent restenosis in patients after coronary drug‐eluting stent implantation

Objective

We evaluated the association between plasma levels of mac‐2 binding protein (M2BP) with the risk of in‐stent restenosis (ISR) after percutaneous coronary intervention (PCI).

Methods

Plasma M2BP levels were compared between 258 patients who experienced ISR at 12‐months post‐PCI and 258 patients, matched for age and sex, without angiographic evidence of ISR.

Results

The plasma M2BP level was significantly higher in the ISR than in the non‐ISR group. On multivariate analysis, adjusted for potential clinical, biochemical, and angiography characteristics, M2BP remained as an independent significant predictor of ISR.

Conclusions

M2BP may be an important predictive biomarker of ISR and may be useful in identifying at‐risk patients.

In‐stent restenosis (ISR) remains a major problem after percutaneous coronary intervention (PCI) and the underlying mechanisms have not yet been fully elucidated.

Plasma Mac‐2 binding protein (M2BP) levels were evaluated in 258 patients who experience ISR and 258 patients without angiographic evidence of ISR at approximately 12 months after PCI.

Notably, plasma M2BP levels were significantly higher patients with (12.91 ± 5.17 μg/ml) than without (10.07 ± 4.86 μg/ml) ISR (p = .001).

Compared with patients with the lowest tertile of M2BP, patients in the mid and highest tertiles of plasma M2BP had a more than 1.3‐fold and 1.8‐fold increased risk of ISR, respectively (both p < .001).

Multivariate logistic regression analysis revealed that, after adjustment for potential clinical factors, elevated plasma M2BP remained an independent predictor of ISR, either as a continuous or as a categorical variable (both p < .001).

M2BP is an important predictive biomarker of ISR and a mediator of growth and migration in vascular smooth muscle cells.

Plasma M2BP assessment may be useful in identifying patients who are at high risk of ISR.

Physalin B inhibits PDGF-BB-induced VSMC proliferation, migration and phenotypic transformation by activating the Nrf2 pathway

Vascular intimal hyperplasia is a hallmark event in vascular restenosis. The excessive proliferation, migration and phenotypic transformation of vascular smooth muscle cells (VSMCs) play important roles in the pathological mechanism of vascular intimal hyperplasia. Physalin B is an alcoholate isolated from Physalis (Solanaceae) that has a wide range of biological activities. However, the effect of physalin B on VSMCs is currently unclear. In this study, we demonstrated that physalin B significantly inhibited the proliferation, migration and phenotypic transformation of VSMCs induced by PDGF-BB. Physalin B also reduced inflammation and oxidative stress in VSMCs induced by PDGF-BB. Mechanistic studies showed that physalin B plays a role mainly by activating Nrf2. After Nrf2 activation, physalin B mitigates oxidative stress by enhancing the expression of the antioxidant gene HO-1; on the other hand, physalin B inhibits the NF-κB pathway to alleviate the inflammatory response. These two effects ultimately reduce the proliferation, migration and phenotypic transformation of VSMCs induced by PDGF-BB. In addition, in the mouse carotid artery ligation model, physalin B prevented intimal hyperplasia and inhibited the proliferation, migration and phenotypic transformation of cells in the hyperplastic intima. In conclusion, we provided significant evidence that physalin B abrogates PDGF-BB-induced VSMC proliferation, migration, phenotypic transformation and intimal hyperplasia by activating Nrf2-mediated signal transduction. Therefore, physalin B may be a potential therapeutic agent for preventing or treating restenosis.

Downregulation of p300/CBP-associated factor inhibits cardiomyocyte apoptosis via suppression of NF-κB pathway in ischaemia/reperfusion injury rats

Cardiomyocyte apoptosis is the main reason of cardiac injury after myocardial ischaemia-reperfusion (I/R) injury (MIRI), but the role of p300/CBP-associated factor (PCAF) on myocardial apoptosis in MIRI is unknown. The aim of this study was to investigate the main mechanism of PCAF modulating cardiomyocyte apoptosis in MIRI. The MIRI model was constructed by ligation of the rat left anterior descending coronary vessel for 30 min and reperfusion for 24 h in vivo. H9c2 cells were harvested after induced by hypoxia for 6 h and then reoxygenation for 24 h (H/R) in vitro. The RNA interference PCAF expression adenovirus was transfected into rat myocardium and H9c2 cells. The area of myocardial infarction, cardiac function, myocardial injury marker levels, apoptosis, inflammation and oxidative stress were detected respectively. Both I/R and H/R remarkably upregulated the expression of PCAF, and downregulation of PCAF significantly attenuated myocardial apoptosis, inflammation and oxidative stress caused by I/R and H/R. In addition, downregulation of PCAF inhibited the activation of NF-κB signalling pathway in cardiomyocytes undergoing H/R. Pretreatment of lipopolysaccharide, a NF-κB pathway activator, could blunt these protective effects of PCAF downregulation on myocardial apoptosis in MIRI. These results highlight that downregulation of PCAF could reduce cardiomyocyte apoptosis by inhibiting the NF-κB pathway, thereby providing protection for MIRI. Therefore, PCAF might be a promising target for protecting against cardiac dysfunction induced by MIRI.

Protective mechanism of Astragalus Polysaccharides against Cantharidin-induced liver injury determined in vivo by liquid chromatography/mass spectrometry metabolomics

Cantharidin (CTD) is a promising anticancer drug; however, its dosage is limited by hepatotoxicity. We previously showed that Astragalus polysaccharides (APS) effectively improved chemical liver injury. In this study, we established a CTD-induced subacute liver injury mouse model and examined the effects of APS on weight, liver indexes, histopathology, serum biochemical indexes and liver metabolism. Compared with the control group, mice in the CTD model group had obvious liver damage, which was partially prevented by APS. Metabolomics demonstrated that CTD caused liver damage mainly by regulating glycerophospholipid metabolism, ABC transporter pathways and choline metabolism in cancer in vivo. APS regulated primary bile acid biosynthesis and glycerophospholipid metabolism, thus decreasing the liver damage caused by CTD. This study revealed the protective mechanism of APS against CTD-induced liver injury from the perspective of metabolomics. The results provide an important basis for analysing the mechanism of CTD-induced liver toxicity and for assessing clinical treatment options to reduce CTD liver toxicity.

Anti-Inflammatory Activity of Sanjie Zhentong Capsule Assessed By Network Pharmacology Analysis of Adenomyosis Treatment

Background

Sanjie Zhentong capsule (SZC) offers excellent effect in treating adenomyosis (AM), which is a common and difficult gynecological disease in the clinic. However, the systematic analysis of its mechanism has not been carried out yet and further studies are needed to reveal the role of SZC.

Methods

A systematic network pharmacology analysis was conducted by integrating construction of SZC compound database and AM target database, prediction of potential active compounds and targets by molecular docking combined with compound-target prediction graph (CTPG), protein-protein interaction (PPI) analysis, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Then, the anti-inflammation experiments in vitro were performed by investigating SZC and the representative compounds regulating nitric oxide (NO), interleukin-6 (IL-6), and interleukin-10 (IL-10).

Results

Our findings show that SZC mainly treated AM by stimulating 28 core targets through 30 key potential active compounds, and affecting 4 crucial pathways. The treatment was associated with inflammation reaction, hormone regulation, cell adhesion, proliferation, and angiogenesis. Additionally, SZC achieved the anti-inflammatory activity by the cooperation of the compounds through inhibiting NO and IL-6, both promoting and inhibiting IL-10.

Conclusion

This study investigated the anti-inflammatory activity of SZC based on a systematic analysis of SZC remedying AM, which was revealed to be one of the essential mechanisms. These findings will provide valuable guidance for further research of the SZC treatment of AM, and help improve the comprehension of SZC pharmacological basis as well as AM pathogenesis.

Downregulation of P300/CBP-Associated Factor Attenuates Myocardial Ischemia-Reperfusion Injury Via Inhibiting Autophagy

Cardiomyocyte autophagy plays an important role in myocardial ischemia-reperfusion injury (MIRI). P300/CBP-associated factor (PCAF) was involved in the regulation of autophagy. However, the role of PCAF in MIRI is currently unknown. This study was to investigate whether downregulation of PCAF attenuate MIRI. The results showed that the expression of PCAF was significantly increased in MIRI in vivo and in vitro. Downregulation of PCAF not only inhibited autophagy and damage of H9c2 cells induced by hypoxia-reoxygenation, but also reduced autophagy and myocardial infarct size during myocardial ischemia-reperfusion in rats. In addition, downregulation of PCAF promoted activation of PI3K/Akt/mTOR signaling pathway in cardiomyocytes during hypoxia-reoxygenation. Wortmannin, a PI3K/Akt inhibitor, could abrogate the effects of downregulation of PCAF on cardiomyocytes autophagy. These results demonstrated that downregulation of PCAF alleviated MIRI by inhibiting cardiomyocyte autophagy through PI3K/Akt/mTOR signaling pathway. Thus, PCAF may be a potential target for prevention and treatment of MIRI.

Tanshinone IIA Can Inhibit Angiotensin II-Induced Proliferation and Autophagy of Vascular Smooth Muscle Cells via Regulating the MAPK Signaling Pathway

To examine the effect of tanshinone IIA on Angiotensin II (Ang II)-induced proliferation and autophagy in vascular smooth muscle cells (VSMCs) and the related mechanism. VSMCs were treated with Ang II with or without tanshinone IIA (1, 5 and 10 µg/mL), and the proliferation, apoptosis in cells with different treatment were examined by methylthiazolyl tetrazolium (MTT) and flow cytometry methods. Moreover, the expression of autophagy related proteins and mitogen-activated protein kinase (MAPK) signaling molecules were examined by RT-quantitative (q)PCR and Western blot methods. Ang II induced significantly increase in the proliferation and autophagy of VSMCs, and the MAPK signaling was activated. Tanshinone IIA can attenuate Ang II-induced effects via down-regulating the MAPK signaling pathway. Tanshinone IIA can inhibit Ang II-induced proliferation and autophagy of VSMCs via regulating the MAPK signaling pathway.

Downregulation of the transcriptional co-activator PCAF inhibits the proliferation and migration of vascular smooth muscle cells and attenuates NF-κB-mediated inflammatory responses

P300/CBP-associated factor (PCAF) regulates vascular inflammation. This study was to explore the effect of PCAF on the proliferation and migrationof vascular smooth muscle cells (VSMCs) and neointimal hyperplasia in balloon-injured rat carotid artery. Downregulation of PCAF remarkably suppressed VSMCs proliferation and migration induced by lipopolysaccharide, and also significantly inhibit the nuclear translocation of nuclear factor-kappaB p65. Meanwhile, downregulation of PCAF inhibited the mRNA expression of tumor necrosis factor-α and interleukin-6, and also the levels in culture supernatants. Moreover, downregulation of PCAF profoundly reduced the intima area and the ratio of intima area to media area in balloon-injured rat carotid artery. In addition, the expression of PCNA and NF-κB p65 in intima were decreased by downregulation of PCAF. These results highlight that PCAF may be a potential target for prevention and treatment of neointimal hyperplasia and restenosis after angioplasty.