Paeonol ameliorates hyperlipidemia and autophagy in mice by regulating Nrf2 and AMPK/mTOR pathways.

BACKGROUND: Hyperlipidemia, inadequate diet, and excessive medication increase the risk of cardiovascular disease. Paeonl (Pae), a phenolic compound found in Peony and Angelica dahurica, can alleviate lipid metabolism disorders and lipotoxicity. However, the molecular mechanism of Pae alleviating hyperlipidemia remains unclear and needs to be further explored. PURPOSE: In this study, we explored whether Pae can prevent hyperlipidemia and investigated the molecular mechanisms. METHODS: The effects of Pae (30, 45, 60mg·kg-1) on hyperlipidemia in Tyloapol-induced WT mice and Nrf2 knockout mice (Pae: 60mg·kg-1) were detected by oil red O staining, HE staining, TG, TC and other indexes. The expression levels of proinflammatory mediators, key lipid proteins and autophagy signaling pathway proteins were analyzed by enzyme-linked immunosorbent assay, western blot and immunofluorescence. The molecular mechanism of Pae alleviating hyperlipidemia was explored through molecular docking technique and in vivo and in vitro experiments. RESULTS: Several studies indicated that Pae effectively improved tyloxapol (Ty)-induced lipid metabolism disorder, as evidenced by decreased triglyceride content, increased carnitine palmitoyltransferase 1 (CPT1), and Sirtuin 1 (Sirt1) protein expression. In addition, Pae ameliorated hyperlipidemia by activating the AMPK/ACC and PI3K/mTOR pathways. Interestingly, the therapeutic effect of Pae on hyperlipidemia was markedly reduced in Nrf2-/- mice. Molecular docking results indicated that Pae and Nrf2 exhibited good binding ability, suggesting that Nrf2 is a core target mediating the effects of Pae in the treatment of hyperlipidemia. Taken together, Pae alleviated hyperlipidemia in vivo and ameliorated lipid accumulation in vitro by activating AMPK/ACC and PI3K/mTOR signaling pathways via Nrf2 binding. CONCLUSION: Our data suggest that paeonol can ameliorate hyperlipidemia and autophagy in mice by regulating Nrf2 and AMPK/mTOR pathways, and it has potential therapeutic value in the occurrence and development of hyperlipidemia.

Paeonol and glycyrrhizic acid in combination ameliorate the recurrent nitroglycerin-induced migraine-like phenotype in rats by regulating the GABBR2/TRPM8/PRKACA/TRPV1 pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Paeonol (PAE) and glycyrrhizic acid (GLY) are predominate components of 14 blood-entering ones of Piantongtang No. 1, which is a traditional Chinese medicine prescription for chronic migraine with minimal side effects. Both paeonol and glycyrrhizic acid exhibit analgesic, neuroprotective and anti-inflammatory properties individually. Our previous research has highlighted their combined effect (PAE + GLY) in ameliorating migraine symptoms. However, there are not yet any studies exploring the mechanism of action of PAE + GLY in the treatment of migraine. AIM OF THE STUDY: This research aimed to determine the mechanism of PAE + GLY in ameliorating the recurrent nitroglycerin-induced migraine-like phenotype in rats. MATERIALS AND METHODS: Using a nitroglycerin-induced migraine model via subcutaneous injection in the neck, we evaluated the effect of PAE + GLY on migraine-like symptoms. Behavioural tests and biomarkers analysis were employed, alongside transcriptome sequencing (RNA-seq). Mechanistic insights were further verified utilising reverse transcription quantitative PCR (RT-qPCR), Western blot (WB), ELISA and immunofluorescence (IF) techniques. RESULTS: Following treatment with PAE + GLY, hyperalgesia threshold and 5-hydroxytryptamine (5-HT) levels increased, and migraine-like head scratching, histamine and calcitonin gene-related peptide (CGRP) levels were reduced. RNA-Seq experiments revealed that PAE + GLY upregulated the expression of Glutamate decarboxylase 2 (GAD2) and γ-aminobutyric acid type B receptor subunit 2 (GABBR2) genes. This upregulation activated the GABAergic synapse pathway, effectively inhibiting migraine attacks. Further validation demonstrated an increase in γ-aminobutyric acid (GABA) content in cerebrospinal fluid post PAE + GLY treatment, coupled with increased expression of dural GAD2, GABBR2 and transient receptor potential channel M8 (TRPM8). Consequently, this inhibited the expression of dural cAMP-dependent protein kinase catalytic subunit alpha (PRKACA) and transient receptor potential channel type 1 (TRPV1), subsequently downregulating p-ERK1/2, p-AKT1, IL-1ß and TNF-α. CONCLUSIONS: Our findings underscore that PAE + GLY ameliorates inflammatory hyperalgesia migraine by upregulating inhibitory neurotransmitters and modulating the GABBR2/TRPM8/PRKACA/TRPV1 pathway.

Hepatoprotective effects of paeonol by suppressing hepatic stellate cell activation via inhibition of SMAD2/3 and STAT3 pathways.

Hepatic stellate cell (HSC) activation is a key event in extracellular matrix accumulation, causing hepatic fibrosis. Therefore, identifying chemicals that inhibit HSC activation is an important therapeutic strategy for hepatic fibrosis. The aim of this study was to investigate the therapeutic effects of paeonol on HSC activation. In LX-2 cells, paeonol inhibited the expression of collagen and decreased the expression of HSC activation markers. In mice with thioacetamide-induced liver fibrosis, paeonol treatment decreased the serum levels of aspartate aminotransferase and alanine transaminase and mRNA expression of α-smooth muscle actin, platelet-derived growth factor-ß, and connective-tissue growth factor. Investigation of the underlying molecular mechanism of paeonol showed that paeonol inhibits the SMAD2/3 and STAT3 signaling pathways that are important for HSC activation. On the basis of these results, paeonol should be investigated and developed further for hepatic fibrosis treatment. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01440-9.

Protective effects of paeonol against cognitive impairment in lung diseases.

Pulmonary inflammation may lead to neuroinflammation resulting in neurological dysfunction, and it is associated with a variety of acute and chronic lung diseases. Paeonol is a herbal phenolic compound with anti-inflammatory and anti-oxidative properties. The aim of this study is to understand the beneficial effects of paeonol on cognitive impairment, pulmonary inflammation and its underlying mechanisms. Pulmonary inflammation-associated cognitive deficit was observed in TNFα-stimulated mice, and paeonol mitigated the cognitive impairment by reducing the expressions of interleukin (IL)-1ß, IL-6, and NOD-like receptor family pyrin domain-containing 3 (NLRP3) in hippocampus. Moreover, elevated plasma miR-34c-5p in lung-inflamed mice was also reduced by paeonol. Pulmonary inflammation induced by intratracheal instillation of TNFα in mice resulted in immune cells infiltration in bronchoalveolar lavage fluid, pulmonary edema, and acute fibrosis, and these inflammatory responses were alleviated by paeonol orally. In MH-S alveolar macrophages, tumor necrosis factor (TNF) α- and phorbol myristate acetate (PMA)-induced inflammasome activation was ameliorated by paeonol. In addition, the expressions of antioxidants were elevated by paeonol, and reactive oxygen species production was reduced. In this study, paeonol demonstrates protective effects against cognitive deficits and pulmonary inflammation by exerting anti-inflammatory and anti-oxidative properties, suggesting a powerful benefit as a potential therapeutic agent.

The efficacy and safety of a fixed-dose combination of apocynin and paeonol, APPA, in symptomatic knee OA: A double-blind, randomized, placebo-controlled, clinical trial.

OBJECTIVE: Apocynin (AP) and paeonol (PA) are low molecular weight phenolic compounds with a broad array of anti-inflammatory and immunoregulatory effects. This study assessed of a fixed-dose combination of APPA in people with symptomatic knee osteoarthritis (OA). METHODS: A multi-center, randomized, placebo-controlled, double-blind phase 2a trial enrolled participants with radiographic knee OA (Kellgren-Lawrence, KL, grades 2-3) and pain ≥40/100 on WOMAC pain subscale, and evaluated the efficacy and safety of oral APPA over a 28-day period. APPA 800 mg or matching placebo was administered twice daily in a 1:1 ratio. Post-hoc analyses explored the response to APPA in sub-groups with more severe pain and structural severity. RESULTS: The two groups were comparable at baseline; 152 subjects were enrolled and 148 completed the trial. There was no statistically significant difference between groups with respect to the primary outcome, WOMAC pain (mean difference between groups was -0.89, 95% CI: -5.62, 3.84, p = 0.71), nor WOMAC function or WOMAC total. However, predefined subgroup analyses of subjects with symptoms compatible with nociplastic/neuropathic pain features showed a statistically significant effect of APPA compared to placebo. Adverse events (mainly gastrointestinal) were mild to moderate. CONCLUSION: Treatment with APPA 800 mg twice daily for 28 days in subjects with symptomatic knee OA was not associated with significant symptom improvement compared to placebo. The treatment was well-tolerated and safe. While the study was not powered for such analysis, pre-planned subgroup analyses showed a significant effect of APPA in subjects with nociplastic pain/severe OA, indicating that further research in the effects of APPA in appropriate patients is warranted.

Paeonol attenuates nonalcoholic steatohepatitis by regulating intestinal flora and AhR/NLRP3/Caspase-1 metabolic pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Non-alcoholic steatohepatitis (NASH) is a common metabolic liver injury disease that is closely associated with obesity and metabolic disorders. Paeonol, an active ingredient found in Moutan Cortex, a traditional Chinese medicine which exhibits significant therapeutic effect on liver protection, has shown promising effects in treating liver diseases, particularly NASH. However, the specific intervention mechanism of paeonol on NASH is still unknown. AIM OF THE STUDY: Our objective is to elucidate the pharmacological mechanism of paeonol in intervening NASH at the in vivo level, focusing on the impact on intestinal flora, tryptophan-related targeted metabolome, and related Aryl hydrocarbon receptor (AhR) pathways. MATERIALS AND METHODS: Here, we explored the intervention effect of paeonol on NASH by utilizing the NASH mouse model. The Illumina highthroughput sequencing technology was preformed to determine the differences of gut microbiota of model and paeonol treatment group. The concentration of Indoleacetic acid is determined by ELISA. The intervention effect of NASH mouse and AhR/NLRP3/Caspase-1 metabolic pathway is analyzed by HE staining, oil red O staining, Immunohistochemistry, Immunofluorescence, Western blot and qRT-PCR assays. Fecal microbiota transplantation experiment also was performed to verify the intervention effect of paeonol on NASH by affecting gut microbiota. RESULTS: Firstly, we discovered that paeonol effectively reduced liver pathology and blood lipid levels in NASH mice, thereby intervening in the progression of NASH. Subsequently, through 16S meta-analysis, we identified that paeonol can effectively regulate the composition of intestinal flora in NASH mice, transforming it to resemble that of normal mice. Specifically, paeonol decreased the abundance of certain Gram-negative tryptophan-metabolizing bacteria. Moreover, we discovered that paeonol significantly increased the levels of metabolites Indoleacetic acid, subsequently enhancing the expression of AhR-related pathway proteins. This led to the inhibition of the NOD-like receptor protein 3 (NLRP3) inflammasome production and inflammation generation in NASH. Lastly, we verified the efficacy of paeonol in intervening NASH by conducting fecal microbiota transplantation experiments, which confirmed its role in promoting the AhR/NLRP3/cysteinyl aspartate specific proteinase (Caspase-1) pathway. CONCLUSIONS: Our findings suggest that paeonol can increase the production of Indoleacetic acid by regulating the gut flora, and promote the AhR/NLRP3/Caspase-1 metabolic pathway to intervene NASH.

Design, synthesis, and evaluation of the novel ozagrel-paeonol codrug with antiplatelet aggregation activities as a potent anti-stroke therapeutic agent.

Introduction: Ischemic stroke is the second most common chronic disease worldwide and is associated with high morbidity and mortality. Thromboembolism and platelet aggregation are the most characteristic features of stroke. Other than aspirin, no standard, accepted, or effective treatment for acute ischemic stroke has been established. Consequently, it is essential to identify novel therapeutic compounds for this condition. Methods: In this study, novel ozagrel/paeonol-containing codrugs were synthesized and characterized using 1H-NMR, 13C-NMR, and mass spectroscopy. Their antiplatelet aggregation activity was evaluated, with compound PNC3 found to exhibit the best effect. Subsequently, studies were conducted to assess its neuroprotective effect, pharmacokinetic properties and model its binding mode to P2Y12 and TXA2, two proteins critical for platelet aggregation. Results: The results indicated that PNC3 has good bioavailability and exerts protective effects against oxygen-glucose deprivation injury in PC12 cells. Molecular docking analysis further demonstrated that the compound interacts with residues located in the active binding sites of the target proteins. Conclusion: The codrugs synthesized in this study display promising pharmacological activities and have the potential for development as an oral formulation.

Paeonol can improve hypoxic-induced H9c2 cells injury and ion channel activity by up-regulating the expression of CKIP-1.

BACKGROUND: Paeonol is a representative active ingredient of the traditional Chinese medicinal herbs Cortex Moutan, which has a well-established cardioprotective effect on ischemic heart disease. However, there is little evidence of the protective effect of paeonol, and its pharmacological mechanism is also unclear. This study aims to explore the protective effect and mechanism of Paeonol on myocardial infarction rat and hypoxic H9c2 cells. METHODS: Myocardial ischemia/reperfusion (I/R) was induced by occlusion of the left anterior descending coronary artery for 1 h followed by 3 h of reperfusion, and then gavage with Paeonol for 7 days. H9c2 cells were applied for the in vitro experiments and hypoxia/reoxygenation (H/R) model was established. CKIP-1 expression was evaluated by qPCR and western blot. The expression of genes involved in apoptosis, inflammation and ion channel was measured by western blot. The currents levels of Nav1.5 and Kir2.1 were measured by whole-cell patch-clamp recording. RESULTS: CKIP-1 expression was decreased in H/R-induced H9c2 cells, which was inversely increased after Paeonol treatment. Paeonol treatment could increase the viability of H/R-induced H9c2 cells and diminish the apoptosis and inflammation of H/R-induced H9c2 cells, while si-CKIP-1 treatment inhibited the phenomena. Moreover, the currents levels of Nav1.5 and Kir2.1 were reduced in H/R-induced H9c2 cells, which were inhibited after Paeonol treatment. Intragastric Paeonol can reduce the ventricular arrhythmias in rats with myocardial infarction. CONCLUSIONS: The protective effects of Paeonol on myocardial infarction rats and hypoxic H9c2 cells were achieved by up-regulating CKIP-1.

Paeonol alleviates postmenopause-induced neuropsychiatric symptoms through the modulation of GPR30 in ovariectomized mice.

ETHNOPHARMACOLOGICAL RELEVANCE: The Moutan cortex (MC), the root bark of Paeonia suffruticosa Anderws (Paeoniaceae), has been historically employed in traditional herbal medicine for addressing women's ailments by replenishing kidney Yin. AIM OF THE STUDY: We aimed to explore if paeonol, an active constituent of MC, could ameliorate neuropsychiatric symptoms, such as anxiety, depression, and cognitive impairments, associated with post-menopausal syndrome (PMS) in an ovariectomized (OVX) mouse model. MATERIALS AND METHODS: The experimental design comprised 6 groups, including a sham group, OVX group, paeonol administration groups (3, 10 or 30 mg/kg, p.o.), and an estradiol (E2)-treated positive control group. Behavioral tests including the open field, novel object recognition, Y-maze, elevated plus-maze, splash, and forced swimming tests were conducted. In addition, we investigated the effets of paeonol on the phosphorylated levels of phosphatidylinositol 3-kinase (PI3K), Akt, and mammalian target of rapamycin (mTOR), as well as on the expression levels of G protein-coupled receptor (GPR30) and brain-derived neurotrophic factor (BDNF) in the prefrontal cortex and hippocampus. RESULTS: Paeonol treatment (10 and 30 mg/kg, p.o.) effectively reversed the cognitive decline in OVX mice, measured by the novel object recognition and Y-maze tests, similar to that in the positive control group. Additionally, it alleviated anxiety- and depressive-like behaviors, as evaluated by the elevated plus-maze test, splash test, and forced swimming test. Paeonol restored GPR30 expression levels in the prefrontal cortex and hippocampus, mirroring the effects of E2 administration. Furthermore, it reversed the reduced expression levels of the PI3K-Akt-mTOR signaling pathway in the prefrontal cortex and hippocampus and increased BDNF expression in the hippocampus of OVX mice. CONCLUSION: This research suggests that paeonol would be beneficial for alleviating PMS-associated cognitive impairment, anxiety and depression.

The anti-atherosclerotic effect of Paeonol against the lipid accumulation in macrophage-derived foam cells by inhibiting ferroptosis via the SIRT1/NRF2/GPX4 signaling pathway.

Atherosclerosis (AS) is the underlying cause of many severe vascular diseases and is primarily characterized by abnormal lipid metabolism. Paeonol (Pae), a bioactive compound derived from Paeonia Suffruticosa Andr., is recognized for its significant role in reducing lipid accumulation. Our research objective is to explore the link between lipid buildup in foam cells originating from macrophages and the process of ferroptosis, and explore the effect and mechanism of Pae on inhibiting AS by regulating ferroptosis. In our animal model, ApoE-deficient mice, which were provided with a high-fat regimen to provoke atherosclerosis, were administered Pae. The treatment was benchmarked against simvastatin and ferrostatin-1. The results showed that Pae significantly reduced aortic ferroptosis and lipid accumulation in the mice. In vitro experiments further demonstrated that Pae could decrease lipid accumulation in foam cells induced by oxidized low-density lipoprotein (LDL) and challenged with the ferroptosis inducer erastin. Crucially, the protective effect of Pae against lipid accumulation was dependent on the SIRT1/NRF2/GPX4 pathway, as SIRT1 knockdown abolished this effect. Our findings suggest that Pae may offer a novel therapeutic approach for AS by inhibiting lipid accumulation through the suppression of ferroptosis, mediated by the SIRT1/NRF2/GPX4 pathway. Such knowledge has the potential to inform the creation of novel therapeutic strategies aimed at regulating ferroptosis within the context of atherosclerosis.

Paeonol interferes with lupus nephritis by regulating M1/M2 polarization of macrophages.

Systemic lupus erythematosus (SLE) is a complex autoimmune disease of unknown etiology. It is marked by the production of pathogenic autoantibodies and the deposition of immune complexes. Lupus nephritis (LN) is a prevalent and challenging clinical complications of SLE. Cortex Moutan contains paeonol as its main effective component. In this study, using the animal model of SLE induced by R848, it was found that paeonol could alleviate the lupus-like symptoms of lupus mouse model induced by R848 activating TLR7, reduce the mortality and ameliorate the renal damage of mice. In order to explore the mechanism of paeonol on lupus nephritis, we studied the effect of paeonol on the polarization of Raw264.7 macrophages in vitro. The experimental results show that paeonol can inhibit the polarization of macrophages to M1 and promote their polarization to M2, which may be related to the inhibition of MAPK and NF-κB signaling pathways. Our research provides a new insight into paeonol in the treatment of lupus nephritis, which is of great importance for the treatment of systemic lupus erythematosus and its complications.

Paeonol promotes longevity and fitness in Caenorhabditis elegans through activating the DAF-16/FOXO and SKN-1/Nrf2 transcription factors.

Paeonol, as one of the most abundant plant-derived polyphenols, has multiple bioactivities including anti-inflammatory, anti-tumor, and anti-cardiovascular diseases. Nevertheless, the anti-aging effects and related mechanisms of paeonol are rarely reported. In this study, we found that paeonol significantly prolonged the mean lifespan of Caenorhabditis elegans (C. elegans) by 28.49% at a dose of 200 µM. Moreover, paeonol promoted the health of C. elegans by increasing the body bending and pharyngeal pumping rates and reducing the lipofuscin accumulation level. Meanwhile, paeonol induced the expression of stress-related genes or proteins by activating the transcription factors DAF-16/FOXO, SKN-1/Nrf2, and HSF-1, which in turn enhanced oxidative and thermal stress tolerance. The mechanism behind the anti-aging effect of paeonol occurred by down-regulating the insulin/IGF-1 signaling (IIS) pathway. Our findings shed new light on the application of paeonol for longevity promotion and human health.

MicroRNA let-7g links foam cell formation and adipogenic differentiation: A key regulator of Paeonol treating atherosclerosis-osteoporosis.

BACKGROUD: High comorbidity rates have been reported in patients with atherosclerosis and osteoporosis, posing a serious risk to the health and well-being of elderly patients. To improve and update clinical practice regarding the joint treatment of these two diseases, the common mechanisms of atherosclerosis and osteoporosis need to be clarified. MicroRNAs (miRNAs), are importance molecules in the pathogenesis of human diseases, including in cardiovascular and orthopedic fields. They have garnered interest as potential targets for novel therapeutic strategies. However, the key miRNAs involved in atherosclerosis and osteoporosis and their precise regulation mechanisms remain unknown. Paeonol (Pae), an active ingredient in Cortex Moutan, has shown promising results in improving both lipid and bone metabolic abnormalities. However, it is uncertain whether this agent can exert a cotherapeutic effect on atherosclerosis and osteoporosis. OBJECTIVE: This study aimed to screen important shared miRNAs in atherosclerotic and osteoporotic complications, and explore the mechanism of the protective effects of Pae against atherosclerosis and osteoporosis in high-fat diet (HFD)-fed ApoE-/- mice. METHODS: An experimental atherosclerosis and osteoporosis model was established in 40-week-old HFD ApoE-/- mice. Various techniques such as Oil Red O staining, HE staining and micro-CT were used to confirm the co-occurrence of these two diseases and efficacy of Pae in addition to the associated biochemical changes. Bioinformatics was used to screen key miRNAs in the atherosclerosis and osteoporosis model, and gene involvement was assessed through serum analyses, qRT-PCR, and western blot. To investigate the effect of Pae on the modulation of the miR let-7g/HMGA2/CEBPß pathway, Raw 264.7 cells were cocultured with bone marrow mesenchymal stem cells (BMSCs) and treated with an miR let-7g mimic/inhibitor. RESULTS: miR let-7g identified using bioinformatics was assessed to evaluate its participation in atherosclerosis-osteoporosis. Experimental analysis showed reduced miR let-7g levels in the atherosclerosis-osteoporosis mice model. Moreover, miR let-7g was required for BMSC - Raw 264.7 cell crosstalk, thereby promoting foam cell formation and adipocyte differentiation. Treatment with Pae significantly reduced plaque accumulation and foam cell number in the aorta while increasing bone density and improving trabecular bone microarchitecture in HFD ApoE-/- mice. Pae also increased the level of miR let-7g in the bloodstream of model mice. In vitro studies, Pae enhanced miR let-7g expression in BMSCs, thereby suppressing the HMGA2/CEBPß pathway to prevent the formation of foam cells and differentiation of adipocytes induced by oxidized low-density lipoprotein (ox-LDL). CONCLUSION: The study results suggested that miR let-7g participates in atherosclerosis -osteoporosis regulation and that Pae acts as a potential therapeutic agent for preventing atherosclerosis-osteoporosis through regulatory effects on the miR let-7g/HMGA2/CEBPß pathway to hinder foam cell formation and adipocyte differentiation.

Ultrasound-Assisted Extraction of Paeonol from Moutan Cortex: Purification and Component Identification of Extract.

Moutan Cortex (MC) is a traditional Chinese medicine that contains abundant medicinal components, such as paeonol, paeoniflorin, etc. Paeonol is the main active component of MC. In this study, paeonol was extracted from MC through an ultrasound-assisted extraction process, which is based on single-factor experiments and response surface methodology (RSM). Subsequently, eight macroporous resins of different properties were used to purify paeonol from MC. The main components of the purified extract were identified by ultra-performance liquid chromatography-quadrupole-time of flight-mass spectrometry (UPLC-Q-TOF-MS/MS). The results indicate the optimal parameters are as follows: liquid-to-material ratio 21:1 mL/g, ethanol concentration 62%, ultrasonic time 31 min, ultrasonic temperature 36 °C, ultrasonic power 420 W. Under these extraction conditions, the actual yield of paeonol was 14.01 mg/g. Among the eight tested macroporous resins, HPD-300 macroporous resin was verified to possess the highest adsorption and desorption qualities. The content of paeonol increased from 6.93% (crude extract) to 41.40% (purified extract) after the HPD-300 macroporous resin treatment. A total of five major phenolic compounds and two principal monoterpene glycosides were characterized by comparison with reference compounds. These findings will make a contribution to the isolation and utilization of the active components from MC.

Paeonol Attenuates Atherosclerosis by Inhibiting Vascular Smooth Muscle Cells Senescence via SIRT1/P53/TRF2 Signaling Pathway.

Atherosclerosis is a chronic inflammatory disease leading to various vascular diseases. Vascular smooth muscle cell (VSMC) senescence promotes atherosclerotic inflammation and the formation of plaque necrosis core, in part through telomere damage mediated by a high-fat diet. Our previous research found that paeonol, a potential anti-inflammatory agent extracted from Cortex Moutan, could significantly improve VSMCs dysfunction. However, the impact of paeonol on the senescence of VSMCs remains unexplored. This study presents the protective effects of paeonol on VSMCs senescence, and its potential activity in inhibiting the progression of atherosclerosis in vivo and in vitro. Sirtuin 1 (SIRT1) is a nuclear deacetylase involved in cell proliferation, senescence, telomere damage, and inflammation. Here, SIRT1 was identified as a potential target of paeonol having anti-senescence and anti-atherosclerosis activity. Mechanistic studies revealed that paeonol binds directly to SIRT1 and then activates the SIRT1/P53/TRF2 pathway to inhibit VSMCs senescence. Our results suggested that SIRT1-mediated VSMCs senescence is a promising druggable target for atherosclerosis, and that pharmacological modulation of the SIRT1/P53/TRF2 signaling pathway by paeonol is of potential benefit for patients with atherosclerosis.

Paeonol Derivative, 6'-Methyl Paeonol, Attenuates Aß-Induced Pathophysiology in Cortical Neurons and in an Alzheimer's Disease Mice Model.

Herbs themselves and various herbal medicines are great resources for discovering therapeutic drugs for various diseases, including Alzheimer's disease (AD), one of the common neurodegenerative diseases. Utilizing mouse primary cortical neurons and DiBAC4(3), a voltage-sensitive indicator, we have set up a drug screening system and identified an herbal extraction compound, paeonol, obtained from Paeonia lactiflora; this compound is able to ameliorate the abnormal depolarization induced by Aß42 oligomers. Our aim was to further find effective paeonol derivatives since paeonol has been previously studied. 6'-Methyl paeonol, one of the six paeonol derivatives surveyed, is able to inhibit the abnormal depolarization induced by Aß oligomers. Furthermore, 6'-methyl paeonol is able to alleviate the NMDA- and AMPA-induced depolarization. When a molecular mechanism was investigated, 6'-methyl paeonol was found to reverse the Aß-induced increase in ERK phosphorylation. At the animal level, mice injected with 6'-methyl paeonol showed little change in their basic physical parameters compared to the control mice. 6'-Methyl paeonol was able to ameliorate the impairment of memory and learning behavior in J20 mice, an AD mouse model, as measured by the Morris water maze. Thus, paeonol derivatives could provide a structural foundation for developing and designing an effective compound with promising clinical benefits.

Paeonol upregulates expression of tumor suppressors TNNC1 and SCARA5, exerting anti-tumor activity in non-small cell lung cancer cells.

Paeonol, a naturally bioactive phenolic ingredient predominantly isolated from Paeonia suffruticosa, has recently garnered significant interest as an anti-tumor agent against diverse carcinomas including non-small cell lung cancer (NSCLC). However, the anti-tumor mechanism of paeonol in NSCLC remains unclear. Cell viability, caspase-3 activity, and apoptosis were evaluated using CCK-8 assay, Caspase-3 Colorimetric Assay Kit, and flow cytometry analysis, respectively. GSE186218 was downloaded from NCBI Gene Expression Omnibus (GEO). The common genes were screened using GEO2R and Draw Venn Diagram software. Expression of troponin C type 1 (TNNC1), scavenger receptor class A member 5 (SCARA5), phosphorylated protein kinase B (AKT) (p-AKT) and AKT was examined using GEPIA database, qRT-PCR and western blot analysis. Paeonol treatment concentration-dependently inhibited cell viability and increased caspase-3 activity and apoptotic rate in NSCLC cells. Only 5 overlapping genes including TNNC1 and SCARA5 were obtained among 232 upregulated genes in GSE186218, 200 underexpressed genes in TCGA-LUAD, and 200 underexpressed genes in TCGA-LUSC according to the Venn diagram software. TNNC1 and SCARA5, two known tumor suppressors, were significantly downregulated in LUAD and LUSC tissues and NSCLC cells. Paeonol dose-dependently upregulated TNNC1 and SCARA5 expression in NSCLC cells. Paeonol suppressed the AKT pathway by upregulating TNNC1 and SCARA5 expression. AKT inhibitor attenuated the effects of TNNC1 or SCARA5 knockdown on the anti-tumor activity of paeonol. In conclusion, paeonol exhibited anti-cancer activity in NSCLC cells through inactivating the AKT pathway by upregulating TNNC1 or SCARA5.

Protective mechanism of Paeonol on central nervous system.

Cerebrovascular diseases involve neuronal damage, resulting in degenerative neuropathy and posing a serious threat to human health. The discovery of effective drug components from natural plants and the study of their mechanism are a research idea different from chemical synthetic medicines. Paeonol is the main active component of traditional Chinese medicine Paeonia lactiflora Pall. It widely exists in many medicinal plants and has pharmacological effects such as anti-atherosclerosis, antiplatelet aggregation, anti-oxidation, and anti-inflammatory, which keeps generally used in the treatment of cardiovascular and cerebrovascular diseases. Based on the therapeutic effects of Paeonol for cardiovascular and cerebrovascular diseases, this article reviewed the pharmacological effects of Paeonol in Alzheimer's disease, Parkinson's disease, stroke, epilepsy, diabetes encephalopathy, and other neurological diseases, providing a reference for the research of the mechanism of Paeonol in central nervous system diseases.

Paeonol ameliorates hippocampal neuronal damage by inhibiting GRM5/GABBR2/ß-arrestin2 and activating the cAMP-PKA signaling pathway in premenstrual irritability rats.

Premenstrual dysphoric disorder (PMDD) is a periodic psychiatric disorder with high prevalence in women of childbearing age, seriously affecting patients' work and life. Currently, the international first-line drugs for PMDD have low efficiency and increased side effects. Paeonol, a major component of the traditional Chinese medicine Cortex Moutan, has been applied in treating PMDD in China with satisfactory results, but the therapeutic mechanism is not fully understood. This study aims to evaluate the therapeutic effects and pharmacological mechanisms of paeonol on the main psychiatric symptoms and hippocampal damage in PMDD. We established a premenstrual irritability rat model by the resident-intruder paradigm and performed elevated plus maze and social interactions. And we employed the HE and Nissl staining techniques to observe the therapeutic effect of paeonol on hippocampal damage in PMDD rats. Subsequently, Elisa, qRT-PCR Array, Western Blotting, and cell models were utilized to elucidate the underlying molecular mechanisms through which paeonol intervenes in treating PMDD. In this study, we demonstrated the therapeutic effects of paeonol on irritability, anxiety, and social withdrawal behaviors in rats. In addition, we found that paeonol significantly reduced the serum corticosterone (CORT) level, improved hippocampal morphological structure and neuron number, and reduced hippocampal neuron apoptosis in PMDD rats. Paeonol reduced GRM5, GABBR2, ß-arrestin2, and GRK3 expression levels in hippocampal brain regions of PMDD rats and activated the cAMP/PKA signaling pathway. Inhibitor cell experiments showed that paeonol specifically ameliorated hippocampal injury by modulating the ß-arrestin2/PDE4-cAMP/PKA signaling pathway. The present study demonstrates, for the first time, that paeonol exerts a therapeutic effect on periodic psychotic symptoms and hippocampal injury in PMDD through inhibiting GRM5/GABBR2/ß-arrestin2 and activating cAMP-PKA signaling pathway. These findings enhance our understanding of the pharmacological mechanism underlying paeonol and provide a solid scientific foundation for its future clinical application.

Paeonol reduces microbial metabolite α-hydroxyisobutyric acid to alleviate the ROS/TXNIP/NLRP3 pathway-mediated endothelial inflammation in atherosclerosis mice.

Gut microbiota dysbiosis is an avenue for the promotion of atherosclerosis (AS) and this effect is mediated partly via the circulating microbial metabolites. More microbial metabolites related to AS vascular inflammation, and the mechanisms involved need to be clarified urgently. Paeonol (Pae) is an active compound isolated from Paeonia suffruticoas Andr. with anti-AS inflammation effect. However, considering the low oral bioavailability of Pae, it is worth exploring the mechanism by which Pae reduces the harmful metabolites of the gut microbiota to alleviate AS. In this study, ApoE-/- mice were fed a high-fat diet (HFD) to establish an AS model. AS mice were administrated with Pae (200 or 400 mg·kg-1) by oral gavage and fecal microbiota transplantation (FMT) was conducted. 16S rDNA sequencing was performed to investigate the composition of the gut microbiota, while metabolomics analysis was used to identify the metabolites in serum and cecal contents. The results indicated that Pae significantly improved AS by regulating gut microbiota composition and microbiota metabolic profile in AS mice. We also identified α-hydroxyisobutyric acid (HIBA) as a harmful microbial metabolite reduced by Pae. HIBA supplementation in drinking water promoted AS inflammation in AS mice. Furthermore, vascular endothelial cells (VECs) were cultured and stimulated by HIBA. We verified that HIBA stimulation increased intracellular ROS levels, thereby inducing VEC inflammation via the TXNIP/NLRP3 pathway. In sum, Pae reduces the production of the microbial metabolite HIBA, thus alleviating the ROS/TXNIP/NLRP3 pathway-mediated endothelial inflammation in AS. Our study innovatively confirms the mechanism by which Pae reduces the harmful metabolites of gut microbiota to alleviate AS and proposes HIBA as a potential biomarker for AS clinical judgment.