Chrysoeriol suppresses hyperproliferation of rheumatoid arthritis fibroblast-like synoviocytes and inhibits JAK2/STAT3 signaling

Apigenin ameliorates lupus nephritis by inhibiting SAT3 signaling in CD8+ T cells

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by widespread organ and tissue involvement, with lupus nephritis (LN) being one of its most severe complications. Dietary flavonoids, as for their anti-inflammatory and antioxidant properties, have shown therapeutic potential under various inflammatory conditions. Apigenin (AP) is one of the most studied phenolics and is found in many fruits, vegetables and herbs. This study aimed to investigate the therapeutic effects and underlying mechanisms of apigenin on LN. We evaluated the effects of apigenin on MRL/lpr mice, a well-established model for spontaneous LN. Apigenin treatment improved peripheral blood profiles, reduced serum inflammatory cytokines (IL-6, IFN-γ, IL-17, TGF-β), lowered levels of autoantibodies (ANA, anti-dsDNA) and alleviated renal damage caused by autoantibodies and inflammatory cell infiltration. The results of immunohistochemistry and transcriptome analysis showed that AP could inhibit the infiltration of CD8+ cells in renal tissues. Single-cell sequencing public data from LN patients identified cytotoxic T lymphocytes (CTLs) as the primary CD8+ T cell subtype in the kidneys, with their differentiation regulated by STAT3. In this study, cell experiments demonstrated that AP can induce apoptosis in CD8+ T cells and reduce their recruitment of macrophages by inhibiting the STAT3/IL-17 signaling pathway. These findings highlight that a diet rich in dietary flavonoids, particularly apigenin, can offer therapeutic benefits for patients with SLE.

The anti-rheumatoid arthritic activity of Artemisia ordosica Krasch. (traditional Chinese/Mongolian medicine) extract in collagen-induced arthritis in rats

OBJECTIVES

Rheumatoid arthritis (RA) seriously affects the daily life of people. The whole plant of Artemisia ordosica Krasch. (AOK) has been used in folk medicine. This study aimed to investigate the in vivo anti-RA effects of AOK extract (AOKE) on collagen-induced arthritis in rats.

METHODS

AOKE (400, 200, or 100 mg/kg) was administered orally to animals for 30 days. Body weight, paw swelling, arthritis index, thymus, and spleen indices, and pathological changes were assessed for effects of AOKE on RA. Furthermore, the inflammatory cytokines in rat serum were detected. In addition, the expressions of STAT3, Caspase-3, Galectin-3, and S100A9 in synovial tissue were researched using immunohistochemistry.

KEY FINDINGS

The AOKE significantly reduced the arthritis indices, paw swelling, spleen, and thymus indices. Meanwhile, AOKE (400 mg/kg) decreased the levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-17A, and increased the level of IL-10 in rat serum. Histopathological examination showed that AOKE reduced inflammatory cell infiltration and cartilage erosion. Then, AOKE decreased the expressions of STAT3, Galectin-3, S100A9, and increased the expression of Caspase-3.

CONCLUSION

AOKE had interesting anti-RA activity in rats, which deserved further research for the development and clinical use of this medicinal resource.

Abelmoschus manihot (L.) medik. seeds alleviate rheumatoid arthritis by modulating JAK2/STAT3 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Abelmoschus manihot (L.) Medik. Seeds (AMS, སོ་མ་ར་ཛ།), a Tibetan classical herbal in China, are rich in flavonoids and phenolic glycosides compounds, such as quercetin and its derivatives. Moreover, it has been found to possess anti-rheumatoid arthritis (RA) effects. Nonetheless, its anti-RA mechanism is yet unknown.

AIM OF THE STUDY

This research aimed to examine the active ingredients of AMS as well as potential pharmacological mechanisms in AMS on RA.

MATERIALS AND METHODS

The ultra-performance liquid chromatography-electrospray ionization-tandem multistage mass spectrometry (UPLC-ESI-IT-MSn) technique was used to determine the primary chemical components of AMS that were responsible for the therapeutic effects on RA. In addition, 36 male Wistar rats weighing between 200 and 220 g were classified at random into six groups [normal control group, collagen-induced arthritis (CIA) group, methotrexate group (positive control, 1.05 mg/kg), AMS group (157.5 mg/kg, 315 mg/kg, 630 mg/kg)]. CIA rats were given AMS extract by intragastric administration for 28 days, and their ankles were photographed to observe the degree of swelling. Further, the arthritis score, paws swelling, and body weight changes of CIA rats were determined to observe whether AMS has any effect on RA, and synovial and cartilage tissue injuries were identified by histopathology. Besides, the levels of IL-10, TNF-α, IL-1β, INF-γ, etc. in serum were estimated by ELISA. Western blot experiments were implemented to identify the expression levels of protein involved in the JAK2/STAT3 signaling pathway in the CIA rats' synovial tissues. Moreover, the mechanisms and targets of active ingredient therapy of AMS for RA were predicted using network pharmacology and then verified using molecular docking.

RESULT

In the present study, 12 compounds were detected by UPLC-ESI-IT-MSn, such as quercetin and its derivative which could be potential active ingredients that contribute to the anti-RA properties of AMS. Our in vivo studies on CIA rats revealed that an AMS-H dose of 630 mg/kg significantly improved joint damage while decreasing the arthritic index and paw swelling. Furthermore, AMS inhibited the INF-γ, IL-6, IL-17, IL-1β, and TNF-α, levels while upregulating the expression of anti-inflammatory cytokines IL-10 and IL-4 in serum. Besides, AMS inhibited the protein Bcl-2/Bax, STAT3, and JAK2 levels, and promoted the expression of Caspase3, SOCS1, and SOCS3 in the JAK2/STAT3 pathway. Additionally, the JAK/STAT signaling pathway was found to perform a remarkable function in the AMS therapy of RA as evidenced by enrichment in GO terms and KEGG pathways. Meanwhile, data from molecular docking experiments indicated that the core targets of PIK3CA, JAK2, and SRC bound stably to the active ingredients of mimuone, 4'-methoxy-bavachromanol, and quercetin.

CONCLUSION

According to these findings, the AMS could improve joint inflammation in CIA rats, and its underlying mechanism could be linked to the regulation of the JAK2/STAT3 pathway. Therefore, AMS might become a promising agent for alleviating inflammation in RA patients.

Pharmacological Activities of Lonicerae japonicae flos and Its Derivative-"Chrysoeriol" in Skin Diseases

Chrysoeriol is an active ingredient derived from the Chinese medicinal herb (CMH) "Lonicerae japonicae flos" in the dried flower bud or bloomed flower of Lonicera japonica Thunberg. Dermatoses are the most common diseases in humans, including eczema, acne, psoriasis, moles, and fungal infections, which are temporary or permanent and may be painless or painful. Topical corticosteroids are widely used in Western medicine, but there are some side effects when it is continuously and regularly utilized in a large dosage. Chrysoeriol is a natural active ingredient, nontoxic, and without any adverse reactions in the treatment of dermatological conditions.

METHODS

Nine electronic databases were searched, including WanFang Data, PubMed, Science Direct, Scopus, Web of Science, Springer Link, SciFinder, and China National Knowledge Infrastructure (CNKI), without regard to language constraints. The pharmacological activities of chrysoeriol from Lonicerae japonicae flos to fight against skin diseases were explained and evaluated through the literature review of either in vitro or in vivo studies.

RESULTS

Chrysoeriol decreased the mRNA levels of proinflammatory cytokines IL-6, IL-1β, and TNF-α. These were transcriptionally regulated by NF-κB and STAT3 to combat skin inflammation. It also showed promising actions in treating many skin ailments including wound healing, depigmentation, photoprotection, and antiaging.

CONCLUSION

The cutaneous route is the best delivery approach to chrysoeriol across the skin barrier. However, toxicity, dosage, and safety assessments of chrysoeriol in a formulation or nanochrysoeriol on the human epidermis for application in skin diseases must be further investigated.

Vetiver aerial parts and roots ameliorate rheumatoid arthritis in complete Freund's adjuvant rat model, a phytochemical profiling and mechanistic study

ETHNOPHARMACOLOGICAL RELEVANCE

Vetiver (Chrysopogon zizanioides) is indigenous to India where it is traditionally used to relief rheumatisms, lumbagos and sprains. Vetiver anti-inflammatory activity has not been previously investigated, and its specific interactions with body inflammation cascade remain largely unknown.

AIM OF THE STUDY

The present work was performed to validate the ethnobotanical use of the plant and compare the anti-inflammatory activities of the ethanolic extracts of the most traditionally used part (aerial part) to that of the root. Furthermore, we attempt to reveal the molecular mechanism of this anti-inflammatory activity in correlation to the chemical composition of C. zizanioides aerial (CA) and root parts (CR).

MATERIALS AND METHODS

Ultraperformance liquid chromatography coupled to high resolution mass spectrometry (UHPLC/HRMS) was used for comprehensive analysis of both CA and CR. The anti-inflammatory effect of both extracts was evaluated in complete Freund's adjuvant (CFA)-induced RA model in Wistar rats.

RESULTS

Phenolic metabolites were predominant in CA and 42 were identified for the first time, while only 13 were identified in CR. Meanwhile, triterpenes and sesquiterpenes were confined to the root extract. In CFA arthritis model, CA showed better anti-inflammatory activity than CR marked by an increase in serum level of IL-10 with simultaneous decrease in pro-inflammatory markers; IL-6, ACPA and TNF-α and was evident in histopathological examination. This anti-inflammatory effect was accompanied by down-regulation of JAK2/STAT3/SOCs3, ERK1/ERK2, TRAF6/c-FOS/NFATC1, TRAF6/NF-κB/NFATC1 and RANKL pathways which were all upregulated after CFA injection. These pathways were modulated to larger extent by CA, except for ERK1/ERK2 which was downregulated more effectively by CR. This differential effect between CA and CR can be explained by the variability in their phytoconstituents profile.

CONCLUSION

In agreement with the ethnobotanical preference, CA extract was more effective than CR extract in reducing the symptoms of RA probably due to its enrichment with flavonoids, lignans, and flavolignans. Both CA and CR reduced the production of inflammatory cytokines through modulating various biological signaling pathways. These findings support the traditional use of vetiver leaves as a remedy for RA and suggest that the use of the whole plant may offer advantage by synergistically affecting more inflammatory pathways.

Recent advances in anti-inflammatory active components and action mechanisms of natural medicines

Inflammation is a series of reactions caused by the body's resistance to external biological stimuli. Inflammation affects the occurrence and development of many diseases. Anti-inflammatory drugs have been used widely to treat inflammatory diseases, but long-term use can cause toxic side-effects and affect human functions. As immunomodulators with long-term conditioning effects and no drug residues, natural products are being investigated increasingly for the treatment of inflammatory diseases. In this review, we focus on the inflammatory process and cellular mechanisms in the development of diseases such as inflammatory bowel disease, atherosclerosis, and coronavirus disease-2019. Also, we focus on three signaling pathways (Nuclear factor-kappa B, p38 mitogen-activated protein kinase, Janus kinase/signal transducer and activator of transcription-3) to explain the anti-inflammatory effect of natural products. In addition, we also classified common natural products based on secondary metabolites and explained the association between current bidirectional prediction progress of natural product targets and inflammatory diseases.

Exploring CircRNA N6-methyladenosine in human rheumatoid arthritis: Hyper-methylated hsa_circ_0007259 as a potential biomarker and its involvement in the hsa_circ_0007259/hsa_miR-21-5p/STAT3 axis

BACKGROUND

N6-methyladenosine (m6A) is a highly enriched modification found in circular RNAs (CircRNAs); however, the ability and mechanism of CircRNAs to encode for m6A function in rheumatoid arthritis (RA) remain poorly understood.

METHODS

We utilized an epitranscriptomic microarray to measure levels and quantities of m6A methylated CircRNAs in synovial tissues of patients with RA and osteoarthritis (OA). We then utilized methylated RNA immunoprecipitation- and MazF-quantitative PCR to identify and validate differentially m6A-methylated RNAs between the groups, conducted a functional enrichment analysis, and selected protein-protein interaction hub genes. Lastly, we predicted and validated the CircRNA/miRNA/mRNA interaction networks.

RESULTS

We detected 4,845 CircRNAs containing m6A in our samples, with 53 CircRNAs upregulated, and 139 CircRNAs downregulated compared to human OA synovial tissue (|fold change| ≥ 1.2 and p ≤ 0.05). The differentially m6A-modified CircRNAs were associated with the interleukin-6-mediated signaling pathway, with an increase in relative m6A-methylated levels of hsa_circ_0007259 in human RA, a significant decrease in hsa_miR-21-5p, and an increase in signal transducer and activator of transcription 3（STAT3）. The Luciferase Reporter Gene assay verified the binding of hsa_circ_0007259 to hsa_miR-21-5p and the subsequent binding of hsa_miR-21-5p to STAT3.

CONCLUSION

We showed a notable increase in the relative m6A-methylated levels of hsa_circ_0007259 in human RA, indicating a potential role of hypermethylated hsa_circ_0007259 in RA pathogenesis. This may provide valuable insight into the mechanism of RA and the possibility of utilizing hsa_circ_0007259 as a valuable biomarker.

Prevention and treatment of inflammatory arthritis with traditional Chinese medicine: Underlying mechanisms based on cell and molecular targets

Inflammatory arthritis, primarily including rheumatoid arthritis, osteoarthritis and ankylosing spondylitis, is a group of chronic inflammatory diseases, whose general feature is joint dysfunction with chronic pain and eventually causes disability in older people. To date, both Western medicine and traditional Chinese medicine (TCM) have developed a variety of therapeutic methods for inflammatory arthritis and achieved excellent results. But there is still a long way to totally cure these diseases. TCM has been used to treat various joint diseases for thousands of years in Asia. In this review, we summarize clinical efficacies of TCM in inflammatory arthritis treatment after reviewing the results demonstrated in meta-analyses, systematic reviews, and clinical trials. We pioneered taking inflammatory arthritis-related cell targets of TCM as the entry point and further elaborated the molecular targets inside the cells of TCM, especially the signaling pathways. In addition, we also briefly discussed the relationship between gut microbiota and TCM and described the role of drug delivery systems for using TCM more accurately and safely. We provide updated and comprehensive insights into the clinical application of TCM for inflammatory arthritis treatment. We hope this review can guide and inspire researchers to further explore mechanisms of the anti-arthritis activity of TCM and make a great leap forward in comprehending the science of TCM.

Chrysanthemum morifolium and Its Bioactive Substance Enhanced the Sleep Quality in Rodent Models via Cl- Channel Activation

Dried Chrysanthemum morifolium (Chry) flowers have been used in Korea as a traditional insomnia treatment. In this study, the sleep-promoting activity and improving sleep quality of Chry extract (ext) and its active substance linarin were analyzed by pentobarbital-induced sleep experiment in mice and electroencephalography (EEG), electromyogram (EMG) analysis in rats. In a dose-dependent manner, Chry ext and linarin promoted longer sleep duration in the pentobarbital-induced sleep test compared to pentobarbital-only groups at both hypnotic and subhypnotic doses. Chry ext administration also significantly improved sleep quality, as seen in the relative power of low-frequency (delta) waves when compared with the control group. Linarin increased Cl- uptake in the SH-SY5Y human cell line and chloride influx was reduced by bicuculline. After administration of Chry ext, the hippocampus, frontal cortex, and hypothalamus from rodents were collected and blotted for glutamic acid decarboxylase (GAD)65/67 and gamma-aminobutyric acid (GABA)A receptors subunit expression levels. The expression of α1-subunits, β2-subunits, and GAD65/67 of the GABAA receptor was modulated in the rodent brain. In conclusion, Chry ext augments pentobarbital-induced sleep duration and enhances sleep quality in EEG waves. These effects might be due to the activation of the Cl- channel.

Chryseriol attenuates the progression of OVA-induced asthma in mice through NF-κB/HIF-1α and MAPK/STAT1 pathways

BACKGROUND

Asthma is a hackneyed chronic inflammatory disease of the airway. Chryseriol (CSR) is a kind of flavonoid, and has the effect of bronchiectasis, indicating its potential application for treating respiratory diseases. However, the functions of CSR in asthma have not been reported till now.

MATERIALS AND METHODS

The histopathologic changes of the lung tissues were assessed by hematoxylin and eosin staining. The cell apoptosis was identified through terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling assay. Total numbers of eosinophils, neutrophils, and macrophages were assessed under microscope. The levels of interleukin (IL)-1β, IL-4, IL-5, and IL-13 were detected by enzyme-linked-immunosorbent serologic assay. The airway hyper-responsiveness (AHR) was evaluated by the whole body plethysmography. The levels of methane dicarboxylic aldehyde, superoxide dismutase, glutathione S-transferase, and glutathione in lung homogenates were confirmed by using corresponding commercial kits. The protein expressions were examined by Western blot analysis.

RESULTS

The ovalbumin (OVA) was utilized to establish asthma mouse model. At first, it was revealed that CSR treatment reduced lung injury in OVA-stimulated mice. Moreover, cell apoptosis was enhanced after OVA stimulation but was attenuated by CSR treatment. In addition, CSR treatment decreased the infiltration of inflammatory cells and the production of inflammatory factors in OVA-treated mice. Further investigations demonstrated that CSR treatment relieved AHR in OVA-stimulated mice. The oxidative stress was strengthened in OVA-treated mice, but these effects were relieved by CSR treatment. Lastly, it was discovered that CSR treatment retarded nuclear factor kappa B (NF-κB)/hypoxia-inducible factor 1 alpha (HIF-1α) and p38 mitogen-activated protein kinase (MAPK)/signal transducer and activator of transcription 1 (STAT1) pathways in OVA-triggered asthma mice.

CONCLUSION

Our findings proved that CSR attenuated the progression of OVA-induced asthma in mice through inhibiting NF-κB/HIF-1α and MAPK/STAT1 pathways. This work might highlight the functions of CSR in the treatment of asthma.

Inhibition of STAT3 signaling contributes to the anti-melanoma effects of chrysoeriol

BACKGROUND

Melanoma is an aggressive malignancy with a high mortality rate. Signal transducer and activator of transcription 3 (STAT3), an oncoprotein, is considered as an effective target for treating melanoma. Chrysoeriol is a flavonoid compound, and possesses anti-tumor activity in lung cancer, breast cancer and multiple myeloma; while whether it has anti-melanoma effects is still not known. Chrysoeriol has been shown to restrain STAT3 signaling in an inflammation mouse model.

PURPOSE

In this study, the anti-melanoma effects of chrysoeriol and the involvement of STAT3 signaling in these effects were investigated.

STUDY DESIGN AND METHODS

CCK8 assays, 5-ethynyl-2'-deoxyuridine (EdU) staining, Annexin V-FITC/PI staining, Western blot analyses of cleaved caspase-9 and wound healing assays were used to study the anti-melanoma effects of chrysoeriol in cell models. A B16F10 melanoma bearing mouse model was used to evaluate the in vivo anti-melanoma effects of chrysoeriol. Indicators of cell proliferation, cell apoptosis and angiogeneis in melanoma tissues were detected by immunohistochemistry (IHC) staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. Immune cells in melanoma tissues were analyzed by flow cytometry. STAT3-overactivated cell models were used to investigate the involvement of STAT3 signaling in the anti-melanoma effects of chrysoeriol. Molecular dynamics (MD) simulations and surface plasmon resonance (SPR) assays were conducted to determine whether chrysoeriol binds to Src, an upstream kinase of STAT3.

RESULTS

The results of cell experiments showed that chrysoeriol dose-dependently inhibited viability, proliferation and migration of, and induced apoptosis in, A375 and B16F10 melanoma cells. Chrysoeriol inhibited the phosphorylation of STAT3, and downregulated the expression of STAT3-target genes involved in melanoma growth and metastasis. Mouse studies showed that chrysoeriol restrained melanoma growth and tumor-related angiogenesis, and altered compositions of immune cells in melanoma microenvironment. Chrysoeriol also inhibited STAT3 signaling in B16F10 allografts. Chrysoeriol's viability-inhibiting effects were attenuated by over-activating STAT3 in A375 cells. Furthermore, chrysoeriol bound to the protein kinase domain of Src, and suppressed Src phosphorylation in melanoma cells and tissues.

CONCLUSION

This study, for the first time, demonstrates that chrysoeriol has anti-melanoma effects, and these effects are partially due to inhibiting STAT3 signaling. Our findings indicate that chrysoeriol has the potential to be developed into an anti-melanoma agent.

Hesperidin inhibits tobacco smoke-induced pulmonary cell proliferation and EMT in mouse lung tissues via the p38 signaling pathway

Tobacco smoke (TS) is the major cause of lung cancer. The abnormal proliferation and epithelial-mesenchymal transition (EMT) of lung cells promote occurrence and development of lung cancer. The p38 pathway intervenes in this cancer development. Hesperidin also serves a role in human health and disease prevention. The roles of p38 in TS-mediated abnormal cell proliferation and EMT, and the hesperidin intervention thereof are not yet understood. In the present study, it was demonstrated that TS upregulated proliferating cell nuclear antigen, vimentin and N-cadherin expression, whereas it downregulated E-cadherin expression, as assessed using western blotting and reverse transcription-quantitative PCR. Furthermore, it was observed that inhibition of the p38 pathway inhibit TS-induced proliferation and EMT. Hesperidin treatment prevented the TS-induced activation of the p38 pathway, EMT and cell proliferation in mouse lungs. The findings of the present study may provide insights into the pathogenesis of TS-related lung cancer.