Paeonol attenuates Substance P-induced urticaria by inhibiting Src kinase phosphorylation in mast cells

BACKGROUND

Treatment of chronic urticaria is challenging, the discovery of effective therapeutic drugs is urgently in demand.

PURPOSE

To study the effect and mechanism of Paeonol targeting mast cells and its therapeutic effect on chronic urticaria.

STUDY DESIGN

We developed a chronic urticaria model in vivo and mast cell model in vitro examined the effect of Paeonol in the treatment of chronic urticaria and its mechanism of action in mast cells.

METHOD

The anti-anaphylactoid effect of Paeonol was evaluated in PCA and systemic anaphylaxis models. The treatment role of Paeonol was studied in urticaria model. The release of cytokines and chemokines was measured using enzyme immunoassay kits. Western blot analysis was conducted to investigate phosphorylation of Src, PI3K, and PLC. In vitro kinase assays were conducted to investigate the kinase activity of Lyn, PLC, PI3K and Src.

RESULTS

In our study, Paeonol was able to attenuate evans blue leakage, serum histamine and chemokine release in a passive skin allergic reaction model. Simultaneously, Paeonol inhibited vasodilation and mast cell degranulation in C57BL/6 mice. Further research found that Paeonol alleviated symptoms such as erythema and rash in the Substance P-induced urticaria model, this is accompanied by inhibiting the release of related inflammatory factors. Validation experiments on mast cells in vitro found that Paeonol inhibited the activation of Src-PI3K/Lyn-PLC-NF-κB signaling pathway by crosslinking with Src kinase. Moreover, calcium influx, mast cell degranulation, cytokines generation and chemotaxis were reduced in LAD2 cells. Molecular docking experiments revealed that Paeonol is a specific antagonist targeting Src kinase in the treatment of skin diseases such as urticaria.

CONCLUSION

Paeonol, a herb-derived phenolic compound, can provide drug candidate for developing new drug in treatment of skin disease such as urticaria.

SIGNIFICANCE STATEMENT

In this study, we primarily examined the effect of Paeonol in the treatment of chronic urticaria and its mechanism of action in mast cells. Interestingly, Paeonol was found to regulate Src kinase activity downstream of MRGPRX2 triggered signaling cascade in mast cells. Therefore, this plant-derived phenolic compound may provide a therapeutic option for the treatment of chronic urticaria.

Paeonol, the active component of Cynanchum paniculatum, ameliorated schizophrenia-like behaviors by regulating the PI3K-Akt-GSK3β-NF-κB signalling pathway in MK-801-treated mice

ETHNOPHARMACOLOGICAL RELEVANCE

Cynanchum paniculatum (Bunge) Kitag. ex H. Hara (Asclepiadaceae) have been traditionally used in East Asia as analgesic or antiviral agents. Interestingly, some Chinese and Korean traditional medicinal books reported that the use of C. paniculatum in the treatment of psychotic symptoms, such as hallucinations and delusions.

AIM OF THE STUDY

In this study, we aimed to investigate whether C. paniculatum could improve sensorimotor gating disruption in mice with MK-801-induced schizophrenia-like behaviors. We also aimed to identify the active component of C. paniculatum that could potentially serve as a treatment for schizophrenia and found that paeonol, the major constituent compound of C. paniculatum, showed potential as a treatment for schizophrenia.

MATERIALS AND METHODS

To assess the effect of paeonol on mice with MK-801-induced schizophrenia-like behaviors, we carried out a series of behavioral tests related with symptoms of schizophrenia. In addition, we utilized Western blotting and ELISA techniques to investigate the antipsychotic actions of paeonol.

RESULT

C. paniculatum extract (100 or 300 mg/kg) and paenol (10 or 30 mg/kg) significantly reversed MK-801-induced prepulse deficits in acoustic startle response test. In addition, paeonol (10 or 30 mg/kg) attenuated social novelty preference and novel object recognition memory on MK-801-induced schizophrenia-like behaviour in mice. Furthermore, the phosphorylation levels of PI3K, Akt, GSK3β and NF-κB, as well as related pro-inflammatory cytokine, such as IL-1β and TNF-α, were significantly reversed by the administration of paeonol (10 or 30 mg/kg) in the prefrontal cortex of MK-801-treated mice.

CONCLUSIONS

Collectively, these data show that paeonol can potentially be used as an agent for treating sensorimotor gating deficits, negative symptoms, and cognitive deficits, such as those observed in schizophrenia with few adverse effects.

Paeonol alleviates neuropathic pain by modulating microglial M1 and M2 polarization via the RhoA/p38MAPK signaling pathway

BACKGROUND

This study aimed to investigate the potential mechanism of paeonol in the treatment of neuropathic pain.

METHODS

Relevant mechanisms were explored through microglial pseudotime analysis and the use of specific inhibitors in cell experiments. In animal experiments, 32 SD rats were randomly divided into the sham operation group, the chronic constrictive injury (CCI) group, the ibuprofen group, and the paeonol group. We performed behavioral testing, ELISA, PCR, Western blotting, immunohistochemistry, and immunofluorescence analysis.

RESULTS

The pseudotime analysis of microglia found that RhoA, Rock1, and p38MAPK were highly expressed in activated microglia, and the expression patterns of these genes were consistent with the expression trends of the M1 markers CD32 and CD86. Paeonol decreased the levels of M1 markers (IL1β, iNOS, CD32, IL6) and increased the levels of M2 markers (IL10, CD206, ARG-1) in LPS-induced microglia. The expression of iNOS, IL1β, RhoA, and Rock1 was significantly increased in LPS-treated microglia, while paeonol decreased the expression of these proteins. Thermal hyperalgesia occurred after CCI surgery, and paeonol provided relief. In addition, paeonol decreased the levels of IL1β and IL8 and increased the levels of IL4 and TGF-β in the serum of CCI rats. Paeonol decreased expression levels of M1 markers and increased expression levels of M2 markers in the spinal cord. Paeonol decreased IBA-1, IL1β, RhoA, RhoA-GTP, COX2, Rock1, and p-p38MAPK levels in the spinal dorsal horn.

CONCLUSION

Paeonol relieves neuropathic pain by modulating microglial M1 and M2 phenotypes through the RhoA/p38 MAPK pathway.

Paeonol inhibits melanoma growth by targeting PD1 through upregulation of miR-139-5p

The abnormal immune response mediated by malignant melanoma is related to PD1. Paeonol has pharmacological antitumor activity. Previous studies have indicated that paeonol induces tumor cell apoptosis, but its underlying mechanism in tumor immunity remains unknown. In this study, malignant melanoma was established in normal and thymectomized mice to determine the important role of the thymus in the antitumor effects of paeonol. Paeonol-treated thymocytes were cocultured with melanoma cell spheres to further evaluate the regulatory role of thymocytes in tumor immune dysfunction. Studies have shown that PD1 may be targeted by miR-139-5p. Our results revealed that tumor-induced thymic atrophy was significantly accompanied by high PD1 expression and low miR-139-5p expression. Interestingly, paeonol significantly reversed thymic atrophy and largely protected thymocytes against low PD1 expression and high miR-139-5p expression. Dual-luciferase assays indicated that miR-139-5p interacted with the 3' untranslated region (3'-UTR) of PD1. These results showed that paeonol alleviates PD1-mediated antitumor immunity by reducing miR-139-5p expression and demonstrated a novel mechanism for melanoma immunotherapy.

Paeonol Attenuates the Endothelial-to-Mesenchymal Transition Induced by TGF-β1 in Human Umbilical Vein Endothelial Cells through ALK5-Smad2/3 Signaling Pathway

Background： Paeonol (Pae)， the main active compound of the root of Paeonia albiflora, is efficacious in treating atherosclerosis (AS). Endothelial dysfunction is throughout the pathological progression of AS. It is expected that inhibition of Endothelial-to-mesenchymal transition (EndMT) will be a key target for AS treatment. Objective： In this study, we investigated the molecular mechanism of the regulatory effect of Pae on EndMT in human umbilical vein endothelial cells (HUVECs). Methods： Cell cytotoxicity, proliferation, and migration were detected by CCK-8, the wound healing assay, and EdU staining, respectively. The protein expressions were measured by Western blot or immunofluorescence staining. Immunofluorescence staining was performed to indicate endothelial cells undergoing EndMT in ApoE-/- mice. In vitro TGF-β1-induced EndMT assays were performed in HUVECs and the effect of Pae was explored. Results：We demonstrated that Pae could improve induced TGF-β1-EndMT in vivo and in vitro. Mechanism study revealed that Pae directly bonds to the activin-like kinase 5 (ALK5, also known as TGFβ type I receptor), inhibited downstream Smad2/3 phosphorylation, and thus alleviated EndMT. Notably, overexpression of ALK5 significantly reversed the inhibitory effect of Pae on EndMT in HUVECs. Conclusion：Our results indicate that ALK5 is a promising druggable target for AS, and pharmacological regulation of ALK5-Smad2/3 signaling pathway with small-molecule holds great potential to benefit AS patients.

Paeonol ameliorates endometrial hyperplasia in mice via inhibiting PI3K/AKT pathway-related ferroptosis

BACKGROUND

Paeonol (Pae) is one of the active ingredients from components of Guizhi Fuling Capsule, a traditional Chinese medicine widely used for the treatment of women's diseases, which exhibits various biological and pharmacological activities.

PURPOSE

The objective of this study was to investigate the molecular mechanism underlying the role of Pae in protecting against endometrial hyperplasia (EH).

METHODS

CCK-8 assay was performed to detect the effect of Pae on cell proliferation. Hematoxylin and eosin (H&E) staining was performed to evaluate uterine tissue structure. A network pharmacology study was performed to search the disease targets. Single-cell transcriptome analysis was performed with uterine tissues from 3 healthy donors and 3 EH patients on 10X Genomics platform. Changes in lipid peroxidation were detected by the MDA reaction. IHC assay, Western blot, immunofluorescence and RT-qPCR were used to study the effects of estradiol and Pae on the expression levels of GPX4, PI3K, AKT, p-PI3K, p-AKT in mice.

RESULTS

Pae treatment resulted in a decrease in cell viability of endometrial epithelial cells. Loss of uterus weight and morphology changes were observed in mice. In addition, Fe iron concentration and MDA levels increased, while the expression of GPX4, p-PI3K and p-AKT diminished.

CONCLUSIONS

Pae exhibited obvious alleviative activity in estradiol-induced mice via PI3K/AKT signaling pathway-regulated ferroptosis.

Paeonol attenuates heart failure induced by transverse aortic constriction via ERK1/2 signalling

CONTEXT

Paeonol (PAE) is the main phytochemical from Cortex Moutan. Its main pharmacological effects are anti-inflammatory and antioxidant, but its cardioprotective effect is unclear.

OBJECTIVE

The study investigates the effects and underlying mechanisms of PAE on transverse aortic constriction (TAC)-induced heart failure (HF) in mice.

MATERIALS AND METHODS

C57BL/6 mice were randomly divided into five groups: sham, TAC, PAE10 (TAC + PAE 10 mg/kg), PAE20 (TAC + PAE 20 mg/kg) and PAE 50 (TAC + PAE 50 mg/kg). Paeonol was intragastrically administered to mice for 4 weeks. Mice were anaesthetized with pentobarbital sodium and underwent cardiac echocardiography using echocardiography system. Serum levels of atrial natriuretic peptide (ANP), tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were measured by enzyme-linked immunosorbent assay (ELISA). Myocardial apoptosis was detected with terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) staining. Haematoxylin-eosin (H&E) and Masson's staining were used for histopathological evaluation. Western and quantitative real-time PCR (qRT-PCR) were performed to detect levels of apoptosis and fibrosis-related proteins.

RESULTS

Echocardiography showed PAE improved cardiac function (LVEF: TAC, 52.3±6.8%; PAE20, 65.8±3.6%; PAE50, 71.4±2.5%) and H&E staining showed PAE alleviated myocardial injury (TAC: 1170.3 ± 134.6 μm²; PAE50: 576.0 ± 53.5 μm²). Western and qRT-PCR results showed that PAE down-regulated the levels of ANP, BNP and α-MHC. In addition, TUNEL and western results showed PAE significantly inhibited apoptosis. Masson and western results showed PAE inhibited cardiac hypertrophy. Western results showed the ERK1/2/JNK pathway could be inhibited by PAE.

DISCUSSION AND CONCLUSIONS

Paeonol regulates ERK1/2/JNK to improve cardiac function, which provides theoretical support for the extensive clinical treatment of HF.

Paeonol protects against doxorubicin-induced cardiotoxicity by promoting Mfn2-mediated mitochondrial fusion through activating the PKCε-Stat3 pathway

INTRODUCTION

The anti-cancer medication doxorubicin (Dox) is largely restricted in clinical usage due to its significant cardiotoxicity. The only medication approved by the FDA for Dox-induced cardiotoxicity is dexrazoxane, while it may reduce the sensitivity of cancer cells to chemotherapy and is restricted for use. There is an urgent need for the development of safe and effective medicines to alleviate Dox-induced cardiotoxicity.

OBJECTIVES

The objective of this study was to determine whether Paeonol (Pae) has the ability to protect against Dox-induced cardiotoxicity and if so, what are the underlying mechanisms involved.

METHODS

Sprague-Dawley rats and primary cardiomyocytes were used to create Dox-induced cardiotoxicity models. Pae's effects on myocardial damage, mitochondrial function, mitochondrial dynamics and signaling pathways were studied using a range of experimental methods.

RESULTS

Pae enhanced Mfn2-mediated mitochondrial fusion, restored mitochondrial function and cardiac performance both in vivo and in vitro under the Dox conditions. The protective properties of Pae were blunted when Mfn2 was knocked down or knocked out in Dox-induced cardiomyocytes and hearts respectively. Mechanistically, Pae promoted Mfn2-mediated mitochondria fusion by activating the transcription factor Stat3, which bound to the Mfn2 promoter in a direct manner and up-regulated its transcriptional expression. Furthermore, molecular docking, surface plasmon resonance and co-immunoprecipitation studies showed that Pae's direct target was PKCε, which interacted with Stat3 and enabled its phosphorylation and activation. Pae-induced Stat3 phosphorylation and Mfn2-mediated mitochondrial fusion were inhibited when PKCε was knocked down. Furthermore, Pae did not interfere with Dox's antitumor efficacy in several tumor cells.

CONCLUSION

Pae protects the heart against Dox-induced damage by stimulating mitochondrial fusion via the PKCε-Stat3-Mfn2 pathway, indicating that Pae might be a promising therapeutic therapy for Dox-induced cardiotoxicity while maintaining Dox's anticancer activity.

Protective effects of paeonol against lipopolysaccharide-induced liver oxidative stress and inflammation in gibel carp (Carassius auratus gibelio)

Paeonol (2'-hydroxy-4'-methoxyacetophenone) is a phenol that exhibits antioxidant and anti-inflammatory capabilities. In this study, the underlying mechanism of paeonol against LPS-induced oxidative stress and inflammatory responses in gibel carp was investigated. Three hundred healthy gibel carp were divided into five groups (n = 9), intraperitoneally injected with LPS and thereafter treated with paeonol (16 mg/kg and 64 mg/kg). Fish were anesthetized with MS-222 (100 mg/L), and samples were collected at 72 h to investigate plasma biochemical indexes, liver histopathology, antioxidant enzymatic activity, and TLR receptor-related gene expression. Fish injected with LPS (20 mg/kg) exhibited significantly increased plasma aminotransferase (ALT), aminotransferase (AST), lactate dehydrogenase (LDH), glucose (GLU), diamine oxidase (DAO), and alkaline phosphatase (ALP) levels (P < 0.05). In addition, LPS challenge significantly enhanced myeloperoxidase (MPO) and malondialdehyde (MDA) contents, whereas those of catalase (CAT) and glutathione peroxidase (GSH-Px) decreased (P < 0.05). However, treatment with paeonol attenuated these LPS-induced changes (P < 0.05). The mRNA expression of TLR4, TIRAP, MyD88, TRAF6, NF-κB, TNF-α, IL-1β, and IL-8, which were activated by LPS challenge (P < 0.05), were downregulated by paeonol. Additionally, histopathological examination demonstrated that paeonol alleviates LPS-induced hepatic tissue lesions in fish. Taken together, the results suggest that paeonol mitigates LPS-induced liver oxidative stress and inflammation in gibel carp.

Paeonol triggers apoptosis in HeLa cervical cancer cells: the role of mitochondria-related caspase pathway

Paeonol is a biologically active component purified from the root bark of Cortex Moutan that exerts pharmacological effects on the cervical cancer. In this study, we aim to evaluate the anti-cervical cancer capacity of paeonol and to investigate the mechanism driving its anti-cervical cancer effect. Paeonol administration markedly restrained the proliferation and caused apoptosis in HeLa cells. Furthermore, paeonol treatment resulted in a mitochondrial dysfunction in HeLa cells, including the inducing of mitochondrial membrane potential (MMP), reactive oxygen species (ROS) production, and the release of cytochrome c. Moreover, the Bcl-2/Bax proportion was obviously downregulated and cleaved caspase-3 expression was evaluated through paeonol treatment. Additionally, the expression of p-PI3K and p-Akt was noticeably reduced in response to paeonol treatment in HeLa cells. Our findings indicated that paeonol exerts an anticancer potential in HeLa cells, at least in a manner, via triggering the mitochondrial pathway of cellular apoptosis by inhibiting PI3K/Akt signaling. Thus, paeonol has great potential as a promising therapeutic compound to resist human cervical cancer.

Paeonol exerts neuroprotective and anticonvulsant effects in intrahippocampal kainate model of temporal lobe epilepsy

Temporal lobe epilepsy (TLE) is presented the most common form of focal epilepsy with involvement of oxidative stress and neuroinflammation as important factors in its development. About one third of epileptic patients are intractable to currently available medications. Paeonol isolated from some herbs with traditional and medicinal uses has shown anti-oxidative and anti-inflammatory effects in different models of neurological disorders. In this research, we tried to evaluate the possible protective effect of paeonol in intrahippocampal kainate murine model of TLE. To induce TLE, kainate was microinjected into CA3 area of the hippocampus and paeonol was administered at two doses of 30 or 50mg/kg. The results of this study showed that paeonol at the higher dose significantly reduces incidence of status epilepticus, hippocampal aberrant mossy fiber sprouting and also preserves neuronal density. Beneficial protective effect of paeonol was in parallel with partial reversal of some hippocampal oxidative stress markers (reactive oxygen species and malondialdehyde), caspase 1, glial fibrillary acidic protein, heme oxygenase 1, DNA fragmentation, and inflammation-associated factors (nuclear factor-kappa B, toll-like receptor 4, and tumor necrosis factor α). Our obtained data indicated anticonvulsant and neuroprotective effects of paeonol which is somewhat attributed to its anti-oxidative and anti-inflammation properties besides its attenuation of apoptosis, pyroptosis, and astrocyte activity.

Hyaluronic acid-cyclodextrin encapsulating paeonol for treatment of atopic dermatitis

The cyclodextrin (CD) was grafted onto hyaluronic acid (HA) to form a topical delivery carrier (HACD) in which Paeonol was loaded in its CD cavity and self-assemble into the polymeric micelles (HACD-PAE) for the treatment of atopic dermatitis. Fluorescence microscope observed that HACD could fast penetrate into the skin and remain stable within 12 h. In vitro penetration test (IVPT) results showed the PAE retentions of HACD-PAE group in the stratum corneum and dermis were 3.35 and 1.78 times improvement than that of PAE group. ATR-FTIR and H&E staining assays indicated HACD could increase the gap of keratinocytes by interacting with corneum lipids and loosening the keratin. Furthermore, HACD-PAE showed the best therapeutic effect on atopic dermatitis mice. Thus HACD could be a promising skin-specific delivery carrier, not only promoting the drug penetrating but increasing its remaining in the skin and play the skin disease therapy and skin-care role.

Paeonol increases the antioxidant and anti-inflammatory capacity of gibel carp (Carassius auratus gibelio) challenged with Aeromonas hydrophila

Paeonol, a naturally occurring polyphenol isolated from medical plant, has been known to exhibit anti-oxidative and anti-inflammatory effects. In order to evaluate the effect of paeonol on Carassius auratus gibelio infected by pathogenic bacteria Aeromonas hydriphila. 750 fish were randomly divided into 5 groups, which separately treated with 0.85% sterile saline (blank), A. hydriphila (negative control), A. hydriphila with paeonol (4 mg/kg, 64 mg/kg), and A. hydriphila with enrofloxacin (12 mg/kg, positive control). Fish were anaesthetized with MS-222 (100 mg/L), and samples were collected at 6 and 72 h after A. hydriphila challenge. The results showed that compared with the negative group, the survival in paeonol groups marked increased by 14.75% and 18.94%. The plasma immunoglobulin M (IgM) was notably increased, and low density lipoprotein (LDL) was significantly decreased in paeonol groups at 6 h (P < 0.05). The antioxidative enzymes catalase (CAT), total antioxidant capacity (T-AOC) and glutathione peroxidase (GSH-Px) were significantly increased in paeonol groups at 6 h, while malondialdehyde (MDA) and myeloperoxidase (MPO) contents were lower (P < 0.05). The inflammatory related genes MyD88 and TLR-5 were significantly downregulated, and the TLR-3 was significantly increased in paeonol groups at 72 h (P < 0.05). In addition, histopathological analyses showed that the lesion in liver, spleen and caudal kidney were considerably attenuated in paeonol groups. In conclusion, paeonol could increase the survival rate, mitigate oxidative damage, inflammation, tissue lesions, and improve the immunity of gibel carp challenged with A. hydrophila.

Paeonol regulates NLRP3 inflammasomes and pyroptosis to alleviate spinal cord injury of rat

Background

Spinal cord injury (SCI) is a life-threatening traumatic disorder. Paeonol has been confirmed to be involved in a variety of diseases. The purpose of this study is to investigate the role of paeonol on SCI progression.

Methods

Sprague Dawley (SD) rat was used for the establishment of SCI model to explore the anti-inflammation, anti-oxidation, and neuroprotective effects of paeonol (60 mg/kg) on SCI in vivo. For in vitro study, mouse primary microglial cells (BV-2) were induced by lipopolysaccharide (LPS)/adenosine triphosphate (ATP) treatment. The effect of paeonol on the polarization of LPS/ATP-induced BV-2 cells was determined by detection the expression inducible nitric oxide synthase (iNOS), tumour necrosis factor alpha (TNF-α), arginase-1 (Arg-1), and interleukin (IL)-10 using qRT-PCR. ELISA was used to assess the levels of IL-1β, IL-18, TNF-α, malondialdehyde (MDA), and glutathione (GSH). Western blotting was conducted to determine the levels of NLRP3 inflammasomes and TLR4/MyD88/NF-κB (p65) pathway proteins.

Results

Paeonol promoted the recovery of locomotion function and spinal cord structure, and decreased spinal cord water content in rats following SCI. Meanwhile, paeonol reduced the levels of apoptosis-associated speck-like protein (ASC), NLRP3, active caspase 1 and N-gasdermin D (N-GSDMD), repressed the contents of IL-1β, IL-18, TNF-α and MDA, and elevated GSH level. In vitro, paeonol exerted similarly inhibiting effects on pyroptosis and inflammation. Meanwhile, paeonol promoted BV-2 cells M2 polarization. In addition, paeonol also inactivated the expression of TLR4/MyD88/NF-κB (p65) pathway.

Conclusion

Paeonol may regulate NLRP3 inflammasomes and pyroptosis to alleviate SCI, pointing out the potential for treating SCI in clinic.

Investigation on the antitumor effects of paeonol against renal cell carcinoma based on network pharmacology and experimental validation

ETHNOPHARMACOLOGICAL RELEVANCE

Renal cell carcinoma (RCC) is the most common cancer of the urinary system, the current treatments for RCC are unsatisfactory. Paeonol is the main pharmacologically active ingredient of the traditional Chinese medicine (TCM) moutan cortex (Paeonia suffruticosa Andrews) and Paeonia albiflora Pall, and has been used in TCM to treat various diseases including cancer. However, the underlying therapeutic mechanisms of paeonol in RCC have not been investigated yet.

AIM OF THE STUDY

This study aimed to explore the potential antitumor effects and mechanisms of paeonol on RCC based on network pharmacology and experimental validation.

MATERIALS AND METHODS

Network pharmacological analysis was performed to predict the potential targets and mechanism of paeonol against RCC. The antitumor effects and the priority targets of paeonol against RCC were further assessed by in vitro experiments.

RESULTS

104 intersection targets shared by paeonol and RCC were collected, 15 hub genes were obtained, among these genes, VEGFA expression was higher in RCC, and the higher expression of IL-6 or lower expression of AKT1, JUN, MAPK1, and MAPK8 were correlated to the shorter overall survival (OS) in RCC patients. GO and KEGG analyses suggested that the genes were mainly enriched in the positive regulation of cell death and apoptosis pathway. In vitro experiments showed that paeonol inhibited 786-O cell proliferation, migration, invasion, and promoted apoptosis. When 786-O cells were treated with paeonol, the expression of Bax increased while Bcl-2 and VEGFA decreased.

CONCLUSION

The present study demonstrated that paeonol might play an essential role in RCC by regulating cell proliferation, apoptosis, metastasis, and invasion through the Bcl-2/Bax signaling pathway and VEGFA, providing a theoretical and experimental scientific basis for future investigations of the antitumor effects of paeonol against RCC.

Paeonol protects against acute pancreatitis by inhibiting M1 macrophage polarization via the NLRP3 inflammasomes pathway

The excessive inflammatory response mediated by macrophage is one of the key factors for the progress of acute pancreatitis (AP). Paeonol (Pae) was demonstrated to exert multiple anti-inflammatory effects. However, the role of Pae on AP is not clear. In the present study, we aimed to investigate the protective effect and mechanism of Pae on AP in vivo and vitro. In the caerulein-induced mild acute pancreatitis (MAP) model, we found that Pae administration reduced serum levels of amylase, lipase, IL-1β and IL-6 and alleviated the histopathological manifestations of pancreatic tissue in a dose-dependent manner. And Pae decrease the ROS generated, restore mitochondrial membrane potential (ΔΨm), inhibit M1 macrophage polarization and NLRP3 inflammasome in bone marrow-derived macrophages (BMDMs) in vitro. In addition, specific NLRP3 inhibitor MCC950 eliminated the protective effect of Pae on AP induced by caerulein in mice. Correspondingly, the inhibitory effect of Pae on ROS generated and M1 polarization was not observed in BMDMs with MCC950 in vitro. Taken together, our datas for the first time confirmed the protective effects of Pae on AP via the NLRP3 inflammasomes Pathway.

Paeonol inhibits the malignancy of Apatinib-resistant gastric cancer cells via LINC00665/miR-665/MAPK1 axis

BACKGROUND

Paeonol is the extractive of Paeonia suffruticosa Andr and is reported to reverse the chemotherapy resistance of cancer cells. The present study explores the role of paeonol in inhibiting the malignant biological behaviors of Apatinib-resistant gastric cancer (GC) cells.

METHODS

The Traditional Chinese Medicine Systems Pharmacology (TCMSP) database was adopted to screen the target genes of paeonol, and the STRING database was employed to construct a protein-protein interaction (PPI) network. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of the target genes was performed employing DAVID online database. The expressions of these target genes in GC tissues and para-cancerous tissues were analyzed with GEPIA database, and GEO datasets (GSE109476 and GSE93415) were utilized to analyze differentially expressed lncRNAs and miRNAs in GC tissues and para-cancerous tissues. The expressions of LINC00665, miR-665 and MAPK1 mRNA in Apatinib-resistant GC cells were detected through quantitative real-time polymerase chain reaction (qRT-PCR). Cell counting kit-8 (CCK-8) assay was conducted to detect cell proliferation; Transwell assays were employed to detect cell migration and invasion, and TdT-mediated dUTP nick end labeling (TUNEL) assay was utilized to detect cell apoptosis. Dual-luciferase reporter gene assay was performed to detect the binding relationships between miR-665 and LINC00665, as well as between miR-665 and MAPK1 mRNA. The expressions of MAPK1 protein and glycolysis-associated proteins (GLUT1, LDHB and HK2) were detected by Western blot. Additionally, a tumor xenograft mice model was constructed to evaluate the effects of paeonol on lung metastasis.

RESULTS

Paeonol could inhibit the proliferation, migration, invasion and glycolysis, and promote the apoptosis of Apatinib-resistant GC cells. TCMSP database suggested that Paeonol had 17 target genes, and 17 target genes were mainly enriched in signaling pathways related to apoptosis, glucose and lipid metabolism, etc.; GEPIA database suggests that MAPK1, among the 17 target genes, was markedly elevated in GC tissues. Paeonol could decrease LINC00665 and MAPK1 expressions in GC cells but increase the expression of miR-665. LINC00665 overexpression, MAPK1 overexpression or inhibition of miR-665 could abolish the inhibitive effects of paeonol on the malignant phenotypes of Apatinib-resistant GC cells. miR-665 is verified as an upstream regulator of MAPK1 and a target of LINC00665. Additionally, paeonol could significantly inhibit the lung metastasis in the tumor xenograft mice model.

CONCLUSIONS

Paeonol can inhibit the malignancy of Apatinib-resistant GC cells through LINC00665/miR-665/MAPK1 axis. For the first time, our study imply that paeonol may be a potential drug to reverse Apatinib-resistant of GC cells.

Effect of paeonol against bacterial growth, biofilm formation and dispersal of Staphylococcus aureus and Listeria monocytogenes in vitro

Previous studies have demonstrated the antibacterial activity of paeonol against bacterial pathogens, but its anti-biofilm activities against Staphylococcus aureus and Listeria monocytogenes remain largely unexplored. Here, the antibacterial and anti-biofilm activities of paeonol against S. aureus and L. monocytogenes were examined using the crystal violet staining assay (CVSA), field emission scanning electron microscopy (FESEM), and confocal laser scanning microscopy (CLSM) analysis. Paeonol effectively inhibited the growth of S. aureus and L. monocytogenes with a minimum inhibitory concentration (MIC) of 500 and 125 μg ml^-1, respectively, and disrupted the integrity of cell membranes. Moreover, sub-MIC paeonol exhibited an inhibitory effect on the attachment of S. aureus and L. monocytogenes to the abiotic surface and biofilm formation. Further, paeonol effectively destroyed cell membranes within biofilms, and dispersed mature biofilms of both strains. The results indicate that paeonol might be a promising antibacterial and anti-biofilm agent for combating infections caused by S. aureus and L. monocytogenes.

Paeonol Ameliorates Cuprizone-Induced Hippocampal Demyelination and Cognitive Deficits through Inhibition of Oxidative and Inflammatory Events

Multiple sclerosis (MS) is a chronic and inflammatory disorder of the central nervous system with autoimmune nature that is typified by varying degrees of demyelination and axonal damage. Paeonol is an active ingredient in some medicinal plants with anti-inflammatory and neuroprotective property. This study was conducted to reveal whether paeonol can alleviate hippocampal demyelination and cognitive deficits in cuprizone-induced murine model of demyelination as a model of MS. C57BL/6 mice received oral cuprizone (400 mg/kg) for 6 weeks, and paeonol was administered p.o. at two doses of 25 or 100 mg/kg, starting from the second week post-cuprizone for 5 weeks. After assessment of learning and memory in different tasks, oxidative stress and inflammation were evaluated besides immunohistochemical assessment of hippocampal myelin basic protein (MBP). Paeonol (100 mg/kg) properly ameliorated cognitive deficits in Y maze, novel object discrimination (NOD) test, and Barnes maze with no significant improvement of performance in passive avoidance task. In addition, paeonol treatment at the higher dose was also associated with partial restoration of hippocampal level of oxidative stress and inflammatory markers including MDA, ROS, GSH, SOD, catalase, NF-kB, and TNF. Besides, paeonol improved MMP as an index of mitochondrial integrity and health and reduced MPO as a factor of neutrophil infiltration. Furthermore, paeonol treatment prevented hippocampal MBP immunoreactivity, indicating its prevention of demyelination. In conclusion, the current study showed the preventive effect of paeonol against cuprizone-induced demyelination and cognitive deficits through reversing most oxidative stress- and inflammation-related parameters in addition to its improvement of mitochondrial health.

Synthesis of novel 3/5(3,5)-(di)nitropaeonol hydrazone derivatives as nematicidal agents

Eighteen novel 3/5(3,5)-(di)nitropaeonol hydrazone derivatives were prepared, and their structures well characterized by ¹H NMR, HRMS, and mp. Due to the steric hindrance, the substituents on the C = N double bond of all hydrazine compounds (except E/Z = 4/1 for IV-1g, IV-1l, IV-2b, and E/Z = 3/2 for IV-1n, IV-3a) adopted E configuration. Among all compounds, four compounds 2, 4, IV-1j, and IV-1n exhibited potent nematicidal activity than their precursor paeonol, especially 5-nitropaeonol (2) and 3,5-dinitropaeonol (4) displayed the most potent nematicidal activity Heterodera glycines in vivo with LC₅₀ values of 32.3307 and 36.7074 mg/L, respectively.

Paeonol administration alleviates cognitive deficits and attenuates neural pathological changes in APP/PS1 mice

Alzheimer's disease typically presents with impaired cognition and pathological morphologic changes, including the accumulation of amyloid-β plaques. Disease-modifying drugs are in urgent need as neuroprotective therapies. Exploration of novel therapeutics for alleviating symptoms of Alzheimer's disease has found promise in plant extracts of functional phenols. Paeonol is a water-soluble phenolic substance that has been shown to confer diverse biological effects, including neuroprotection. An Alzheimer's disease model of APP/PS1 double transgenic mice was used in this study, and the therapeutic effects of paeonol were assessed after three weeks' administration. It was found that paeonol treatment significantly increased behavioral performance in the Morris water maze test and increased discrimination rate in the novel object recognition test compared to vehicle-treated APP/PS1 mice. Histologically, paeonol treatment significantly alleviated the Aβ plaque burden, reduced neural loss, inhibited microglia activation, and decreased neuroinflammation in the brain of APP/PS1 mice. In addition, a number of Alzheimer's disease-related synaptic plasticity deficits were ameliorated. The present results indicate that paeonol significantly relieved amyloid-β deposition and amyloid-β -mediated neuropathology in the brain of APP/PS1 mice, suggesting the potential of paeonol as a preventive and therapeutic agent for Alzheimer's disease.

Paeonol Ameliorates Cognitive Deficits in Streptozotocin Murine Model of Sporadic Alzheimer's Disease via Attenuation of Oxidative Stress, Inflammation, and Mitochondrial Dysfunction

Intracerebroventricular (ICV) microinjection of diabetogenic drug streptozotocin (STZ) in rodents consistently produces a model of sporadic Alzheimer's disease (sAD) which is characterized by tau pathology and concomitant cognitive decline, insulin resistance, neuroinflammation, oxidative stress, and mitochondrial malfunction. Paeonol is an active phenolic component in some medicinal plants like Cortex Moutan with neuroprotective efficacy via exerting anti-inflammatory and anti-oxidative effects. This study was conducted to assess beneficial effect of paeonol in amelioration of cognitive deficits in ICV STZ rat model of sAD. STZ (3 mg/kg) was microinjected into the lateral ventricles on days 0 and 2, and paeonol was given p.o. at two doses of 25 (low) or 100 (high) mg/kg from day 0 (post-surgery) till day 24 post-STZ. Cognitive performance was evaluated in different tasks, and oxidative stress- and inflammation-related parameters were measured in addition to immunohistochemical assessment of glial fibrillary acidic protein (GFAP) as a marker of astrocytes. Paeonol at the higher dose ameliorated cognitive deficits in Barnes maze, novel object recognition (NOR) task, Y maze, and passive avoidance test. In addition, paeonol partially reversed hippocampal malondialdehyde (MDA), reactive oxygen species (ROS), total antioxidant capacity (TAC), superoxide dismutase (SOD), catalase, glutathione reductase, tumor necrosis factor α (TNFα), interleukin 6 (IL-6), mitochondrial membrane potential (MMP), myeloperoxidase (MPO), and acetylcholinesterase (AChE) activity. Paeonol treatment was also associated with lower hippocampal immunoreactivity for GFAP. This study showed that paeonol can alleviate cognitive disturbances in ICV STZ rat model of sAD via ameliorating neuroinflammation, oxidative stress, mitochondrial dysfunction, and also through its attenuation of astrogliosis.

Paeonol inhibits profibrotic signaling and HOTAIR expression in fibrotic buccal mucosal fibroblasts

BACKGROUND/PURPOSE

Betel nut chewing is the major risk factor of oral submucous fibrosis (OSF). Various studies have sought to discover alternative strategies to alleviate oral fibrogenesis. In the present study, we aimed to evaluate the anti-fibrosis effect of paeonol, a phenolic component derived from Paeonia Suffruticosa.

METHODS

The cytotoxicity of paeonol was tested using normal and fibrotic buccal mucosal fibroblasts (fBMFs) derived from OSF tissues. Collagen gel contraction, Transwell migration, invasion, and wound healing capacities were examined. Besides, the activation of TGF-β/Smad2 signaling and expression levels of type I collagen, α-SMA, and long non-coding RNA HOTAIR were measured as well.

RESULTS

Paeonol exerted a higher cytotoxic effect on fBMFs compared to normal BMFs. The arecoline-induced myofibroblast activities, including collagen gel contractility, cell motility, and wound healing ability were all suppressed by paeonol treatment. In addition, the activation of the TGF-β/Smad2 pathway was inhibited along with a lower expression of α-SMA and type I collagen in paeonol-treated cells. Also, the administration of paeonol decreased the mRNA expression of HOTAIR in fBMFs.

CONCLUSION

Our results indicate that paeonol may be a promising compound to attenuate the progression of oral fibrogenesis in OSF patients.

Paeonol inhibits human lung cancer cell viability and metastasis in vitro via miR-126-5p/ZEB2 axis

Paeonol exerted an effect in lung cancer, but the underlying mechanism remained vague. In this research, we assessed the effects of Paeonol and microRNA (miR)-126-5p on the viability, migration, invasion, and epithelial-mesenchymal transition (EMT) of lung cancer cells. Lung cancer cells and BEAS-2B cells were treated with Paeonol, and viability was detected by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di- phenytetrazoliumromide (MTT) assay. The migration and invasion of lung cancer cells after treatment with Paeonol at 40 μg/mL or 80 μg/mL were detected by wound healing assay and Transwell assay, respectively. The effects of Paeonol on transforming growth factor-β1 (TGF-β1)-induced EMT and relative expressions of EMT-related proteins were determined using Western blot. The target gene of miR-126-5p and the binding sites between them were predicted by TargetScan, and confirmed using dual-luciferase reporter assay. Relative expressions of miR-126-5p, its target gene and EMT-related proteins were determined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. Rescue assay was performed to analyze the relation between Paeonol and miR-126-5p. Paeonol down-regulated cell viability and inhibited migration, invasion and TGF-β1-induced EMT while up-regulating miR-126-5p expression in lung cancer cells as the dose increased. However, miR-126-5p inhibitor could reverse the effect of Paeonol. ZEB2 was the target gene of miR-126-5p, and silencing ZEB2 expression reversed the effects of miR-126-5p downregulation. Paeonol also regulated the expression of ZEB2 in lung cancer cells, and this regulation depends on the regulation of miR-126-5p. Paeonol inhibits human lung cancer cell viability and metastasis via the miR-126-5p/ZEB2 axis, and could be adopted as a potential agent for lung cancer treatment.

Paeonol promotes Opa1-mediated mitochondrial fusion via activating the CK2α-Stat3 pathway in diabetic cardiomyopathy

Diabetes disrupts mitochondrial function and often results in diabetic cardiomyopathy (DCM). Paeonol is a bioactive compound that has been reported to have pharmacological potential for cardiac and mitochondrial protection. This study aims to explore the effects of paeonol on mitochondrial disorderes in DCM and the underlying mechanisms. We showed that paeonol promoted Opa1-mediated mitochondrial fusion, inhibited mitochondrial oxidative stress, and preserved mitochondrial respiratory capacity and cardiac performance in DCM in vivo and in vitro. Knockdown of Opa1 blunted the above protective effects of paeonol in both diabetic hearts and high glucose-treated cardiomyocytes. Mechanistically, inhibitor screening, siRNA knockdown and chromatin immunoprecipitation experiments showed that paeonol-promoted Opa1-mediated mitochondrial fusion required the activation of Stat3, which directly bound to the promoter of Opa1 to upregulate its transcriptional expression. Moreover, pharmmapper screening and molecular docking studies revealed that CK2α served as a direct target of paeonol that interacted with Jak2 and induced the phosphorylation and activation of Jak2-Stat3. Knockdown of CK2α blunted the promoting effect of paeonol on Jak2-Stat3 phosphorylation and Opa1-mediated mitochondrial fusion. Collectively, we have demonstrated for the first time that paeonol is a novel mitochondrial fusion promoter in protecting against hyperglycemia-induced mitochondrial oxidative injury and DCM at least partially via an Opa1-mediated mechanism, a process in which paeonol interacts with CK2α and restores its kinase activity that subsequently increasing Jak2-Stat3 phosphorylation and enhancing the transcriptional level of Opa1. These findings suggest that paeonol or the promotion of mitochondrial fusion might be a promising strategy for the treatment of DCM.