Kurarinone Attenuates Collagen-Induced Arthritis in Mice by Inhibiting Th1/Th17 Cell Responses and Oxidative Stress

Prenylated Flavonoids in Sophora flavescens: A Systematic Review of Their Phytochemistry and Pharmacology

Sophora flavescens has been widely used in traditional Chinese medicine for over 1700 years. This plant is known for its heat-clearing, damp-drying, insecticidal, and diuretic properties. Phytochemical research has identified prenylated flavonoids as a unique class of bioactive compounds in S. flavescens. Recent pharmacological studies reveal that the prenylated flavonoids from S. flavescens (PFS) exhibit potent antitumor, anti-inflammatory, and glycolipid metabolism-regulating activities, offering significant therapeutic benefits for various diseases. However, the pharmacokinetics and toxicological profiles of PFS have not been systematically studied. Despite the diverse biological effects of prenylated flavonoid compounds against similar diseases, their structure-activity relationship is not yet fully understood. This review aims to summarize the latest findings regarding the chemical composition, drug metabolism, pharmacological properties, toxicity, and structure-activity relationship of prenylated flavonoids from S. flavescens. It seeks to highlight their potential for clinical use and suggest directions for future related studies.

C-reactive protein lowers the serum level of IL-17, but not TNF-α, and decreases the incidence of collagen-induced arthritis in mice

The biosynthesis of C-reactive protein (CRP) in the liver is increased in inflammatory diseases including rheumatoid arthritis. Previously published data suggest a protective function of CRP in arthritis; however, the mechanism of action of CRP remains undefined. The aim of this study was to evaluate the effects of human CRP on the development of collagen-induced arthritis (CIA) in mice which is an animal model of autoimmune inflammatory arthritis. Two CRP species were employed: wild-type CRP which binds to aggregated IgG at acidic pH and a CRP mutant which binds to aggregated IgG at physiological pH. Ten CRP injections were given on alternate days during the development of CIA. Both wild-type and mutant CRP reduced the incidence of CIA, that is, reduced the number of mice developing CIA; however, CRP did not affect the severity of the disease in arthritic mice. The serum levels of IL-17, IL-6, TNF-α, IL-10, IL-2 and IL-1β were measured: both wild-type and mutant CRP decreased the level of IL-17 and IL-6 but not of TNF-α, IL-10, IL-2 and IL-1β. These data suggest that CRP recognizes and binds to immune complexes, although it was not clear whether CRP functioned in its native pentameric or in its structurally altered pentameric form in the CIA model. Consequently, ligand-complexed CRP, through an as-yet undefined mechanism, directly or indirectly, inhibits the production of IL-17 and eventually protects against the initiation of the development of arthritis. The data also suggest that IL-17, not TNF-α, is critical for the development of autoimmune inflammatory arthritis.

Kurarinone regulates Th17/Treg balance and ameliorates autoimmune uveitis via Rac1 inhibition

INTRODUCTION

Autoimmune uveitis (AU) is a severe intraocular autoimmune disorder with a chronic disease course and a high rate of blindness. Kurarinone (KU), a major component of the traditional Chinese medicine Sophorae Flavescentis Radix, possesses a wide spectrum of activities and has been used to treat several inflammation-related diseases.

OBJECTIVE

We aimed to investigate the effects of KU on AU and its modulatory mechanisms.

METHODS

We used an experimental autoimmune uveitis (EAU) animal model and characterized the comprehensive immune landscape of KU-treated EAU mice using single-cell RNA sequencing (scRNA-seq). The retina and lymph nodes were analyzed. The siRNAs and selective inhibitors were used to study the signaling pathway. The effect of KU on peripheral blood mononuclear cells (PBMCs) from uveitis patients was also examined.

RESULTS

We found that KU relieved chorioretinal lesions and immune cell infiltration in EAU model mice. Subsequent single-cell analysis revealed that KU downregulated the EAU-upregulated expression of inflammatory and autoimmune-related genes and suppressed pathways associated with immune cell differentiation, activation, and migration in a cell-specific manner. KU was implicated in restoring T helper 17 (Th17)/regulatory T (Treg) cell balance by alleviating inflammatory injury and elevating the expression of modulatory mediators in Tregs, while simultaneously ameliorating excessive inflammation by Th17 cells. Furthermore, Rac1 and the Id2/Pim1 axis potentiated the pathogenicity of Th17 cells during EAU, which was inhibited by KU treatment, contributing to the amelioration of EAU-induced inflammation and treatment of AU. In addition, KU suppressed inflammatory cytokine production in activated human PBMCs by inhibiting Rac1. Integration of the glucocorticoid-treated transcriptome suggests that KU has immunomodulatory effects on lymphocytes.

CONCLUSION

Our study constructed a high-resolution atlas of the immunoregulatory effects of KU treatment on EAU and identified its potential therapeutic mechanisms, which hold great promise in treating autoimmune disorders.

Dietary oleacein, a secoiridoid from extra virgin olive oil, prevents collagen-induced arthritis in mice

Olacein (OLA), one of the main secoiridoids derived from extra virgin olive oil (EVOO), has been shown to modulate oxidative and inflammatory responses in various pathological conditions; however, its potential benefit in joint disorders such as rheumatoid arthritis (RA) is unknown. Therefore, this study was designed to evaluate the preventive role of the effects of an OLA-supplemented diet in the murine model of collagen-induced arthritis (CIA), delving into the possible mechanisms and signaling pathways involved. Animals were fed an OLA-enriched preventive diet for 6 weeks prior to CIA induction and until the end of the experimental time course. On day 43 after the first immunization, mice were sacrificed: blood was collected, and paws were histologically and biochemically processed. Dietary OLA prevented collagen-induced rheumatic bone, joint and cartilage conditions. Circulating matrix metalloproteinase (MMP)-3 and proinflammatory cytokine (IL-6, IL-1β, TNF-α, IL-17) levels were significantly decreased in the joint, as well as MMP-9 and cathepsin-K (CatK) expression in secoiridoid-fed animals. In addition, dietary OLA was able to decrease COX-2, mPGES-1 and iNOS protein expressions and, also, PGE2 levels. The mechanisms possibly involved in these protective effects could be related to the activation of the Nrf-2/HO-1 axis and the inhibition of proinflammatory signaling pathways, including JAK-STAT, MAPKs and NF-κB, involved in the production of inflammatory and oxidative mediators. These results support the interest of OLA, as a nutraceutical intervention, in the management of RA.

Chlorophytum borivilianum aqueous root extract prevents deterioration of testicular function in mice and preserves human sperm function in hydrogen peroxide (H2O2)-induced oxidative stress

ETHNOPHARMACOLOGICAL RELEVANCE

Chlorophytum borivilianum (C. borivilianum) (CB) has traditionally been used to treat male sexual dysfunctions and has been claimed to possess aphrodisiac properties.

AIM OF THE STUDY

To investigate the ability of CB to ameliorate H2O2-induced oxidative stress in testes and sperm in mice and prevent H2O2-induced oxidative in human sperm.

MATERIALS AND METHODS

Oxidative stress was induced in male mice by pre-exposure to 2% H2O2 orally for seven consecutive days, followed by 100 and 200 mg/kg b. w. administration. CB for another seven days. At the end of treatment, mice were sacrificed and testes and epididymal sperm were harvested. Serum FSH, LH and testosterone levels were measured and sperm parameters were obtained. Meanwhile, oxidative stress levels in mice testes and sperm, steroidogenesis and spermatogenesis markers in mice testes were assessed by molecular biological techniques. In another experiment, sperm from thirty-two healthy fertile men were incubated with 200 μM H2O2 and CB (100 and 200 μg/ml) simultaneously and were then evaluated for sperm parameter changes.

RESULTS

In mice, CB administration ameliorates persistent increases in oxidative stress and decreases in anti-oxidative enzyme levels in testes and sperm following H2O2 pre-exposure. Additionally, CB also helps to ameliorate deterioration in sperm parameters and testicular steroidogenesis and spermatogenesis and restores the serum FSH, LH and testosterone levels near normal in mice. In humans, CB helps to prevent deterioration in sperm parameters following H2O2 exposure.

CONCLUSION

CB is potentially useful to preserve the male reproductive capability and subsequently male fertility in high oxidative stress conditions.

Therapeutic potential of Coptis chinensis for arthritis with underlying mechanisms

Arthritis is a common degenerative disease of joints, which has become a public health problem affecting human health, but its pathogenesis is complex and cannot be eradicated. Coptis chinensis (CC) has a variety of active ingredients, is a natural antibacterial and anti-inflammatory drug. In which, berberine is its main effective ingredient, and has good therapeutic effects on rheumatoid arthritis (RA), osteoarthritis (OA), gouty arthritis (GA). RA, OA and GA are the three most common types of arthritis, but the relevant pathogenesis is not clear. Therefore, molecular mechanism and prevention and treatment of arthritis are the key issues to be paid attention to in clinical practice. In general, berberine, palmatine, coptisine, jatrorrhizine, magnoflorine and jatrorrhizine hydrochloride in CC play the role in treating arthritis by regulating Wnt1/β-catenin and PI3K/AKT/mTOR signaling pathways. In this review, active ingredients, targets and mechanism of CC in the treatment of arthritis were expounded, and we have further explained the potential role of AHR, CAV1, CRP, CXCL2, IRF1, SPP1, and IL-17 signaling pathway in the treatment of arthritis, and to provide a new idea for the clinical treatment of arthritis by CC.

Morin, the PPARγ agonist, inhibits Th17 differentiation by limiting fatty acid synthesis in collagen-induced arthritis

T helper (Th) 17 cells highly contribute to the immunopathology of rheumatoid arthritis. Morin, a natural flavonoid, owns well anti-arthritic action but unclear effect on Th17 differentiation. This study tried to solve this issue and explore the mechanisms in view of cellular metabolism. Naïve CD4+ T cells were treated with anti-CD3/CD28 along with Th17-inducing cytokines. Morin was shown to block Th17 differentiation without affecting cell viability even when Foxp3 was dampened. The mechanisms were ascribed to the limited fatty acid synthesis by restricting FASN transcription, as indicated by metabolomics analysis, nile red staining, detection of triglycerides, FASN overexpression, and addition of palmitic acid. Moreover, morin had slight effect on cell apoptosis and protein palmitoylation during Th17 differentiation, but blocked the binding of RORγt to promoter and CNS2 region of Il17a gene. Oleic acid rescued the inhibition of morin on RORγt function, and Th17-inducing cytokines could not induce RORγt function in SCD1-defficient cells, suggesting that oleic acid but not palmitic acid was the direct effector in the action of morin. Then, PPARγ was identified as the target of morin, and GW9662 or PPARγ CRISPR/Cas9 KO plasmid weakened its above-mentioned effects. The transrepression of FASN by morin was owing to physical interaction between PPARγ and Sp1, and the importance of Sp1 in Th17 differentiation was confirmed by siSp1. Finally, the effects and mechanisms for morin-dampened Th17 responses were confirmed in collagen-induced arthritis (CIA) mice. Collectively, morin inhibited Th17 differentiation and alleviated CIA by limiting fatty acid synthesis subsequent to PPARγ activation.

Research of Pathogenesis and Novel Therapeutics in Arthritis 3.0

Arthritis has a high prevalence globally and includes over 100 types, the most common of which are rheumatoid arthritis (RA), osteoarthritis (OA), psoriatic arthritis (PsA), and inflammatory arthritis [...].

CXCR3 antagonist NBI-74330 mitigates joint inflammation in Collagen-Induced arthritis model in DBA/1J mice

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by uncontrolled synovial proliferation, pannus formation, cartilage injury, and bone destruction. We used the CXCR3-specific antagonist NBI-74330 to block T-cell-mediated signaling in a DBA/1J mouse model of collagen-induced arthritis (CIA). After CIA induction, DBA/1J mice were treated with NBI-74330 (100 mg/kg) daily from day 21 until day 34 and evaluated for arthritic score and histopathological changes. Furthermore, using flow cytometry, we investigated the effects of NBI-74330 on Th1 (IFN-γ, TNF-α, T-bet, STAT4, Notch-3, and RANKL), Th17 (IL-21, IL-17A, STAT3, and RORγt), and Th22 (IL-22) cells in splenic CD4⁺ and CXCR3⁺T-cells. We also used RT-PCR to assess the effect of mRNA levels of IFN-γ, TNF-α, T-bet, RANKL, IL-17A, RORγt, and IL-22 in knee tissues. The IFN-γ, TNF-α, and IL-17A serum protein levels were measured using ELISA. Compared to vehicle-treated CIA mice, the severity of arthritic scores and histological severity of inflammation decreased significantly in NBI-74330-treated CIA mice. Moreover, compared to vehicle-treated CIA mice, the percentages of CD4⁺IFN-γ⁺, CD4⁺TNF-α⁺, CD4⁺T-bet⁺, CD4⁺STAT4⁺, CD4⁺Notch-3⁺, CXCR3⁺IFN-γ⁺, CXCR3⁺TNF-α⁺, CXCR3⁺T-bet⁺, CXCR3⁺STAT4⁺, CXCR3⁺Notch-3⁺, CD4⁺RANKL⁺, CD4⁺IL-21⁺, CD4⁺IL-17A⁺, CD4⁺STAT3⁺, CD4⁺RORγt⁺, and CD4⁺IL-22⁺ cells decreased in NBI-74330-treated CIA mice. Furthermore, NBI-74330-treatment downregulated IFN-γ, TNF-α, T-bet, RANKL, STAT3, IL-17A, RORγt, and IL-22 mRNA levels. Serum IFN-γ, TNF-α, and IL-17A levels were significantly lower in NBI-74330-treated CIA mice than in vehicle-treated CIA mice. This study demonstrates the antiarthritic effects of NBI-74330 in CIA mice. Therefore, these data suggest that NBI-74330 could be considered a potential RA treatment.

Expression of Nrf2 protein in serum of patients with rheumatoid arthritis: A novel indicator for disease activity and disease prognosis

OBJECTIVE

This study aimed to detect the expression level of nuclear factor erythroid 2-related factor 2 (Nrf2) in the serum of patients with rheumatoid arthritis (RA) to clarify the correlation between Nrf2 levels and medical parameters, such as disease activity, pro-inflammatory factor, clinical characteristics, as well as changes after treatment.

METHODS

Serum samples were collected from 100 patients with RA and 42 normal controls (NCs). Serum levels of Nrf2 protein, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-17A, and malondialdehyde (MDA) were analyzed. The receiver operating characteristic (ROC) curve was adopted to assess the potential of Nrf2 to predict different levels of disease activity in patients with RA. The relationship between clinical variables and parameters were evaluated.

RESULTS

For the first time, it was reported that Nrf2 levels were significantly elevated in the serum of patients with RA compared to those of NCs, as were the MDA levels. The levels of Nrf2 were positively correlated with the disease activity and pro-inflammatory factor levels. The significant cut-off points for Nrf2 to determine RA disease activity were 0.69 ng/mL, 0.69 ng/mL and 1.18 ng/mL. Levels of Nrf2 were higher in RA patients with wrist joint involvement and interstitial lung disease. Moreover, Nrf2 levels decreased after treatment.

CONCLUSIONS

Serum Nrf2 protein level is potentially a novel indicator to monitor disease activity and prognosis in patients with RA.

Role of reactive oxygen species and mitochondrial damage in rheumatoid arthritis and targeted drugs

Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial inflammation, pannus formation, and bone and cartilage damage. It has a high disability rate. The hypoxic microenvironment of RA joints can cause reactive oxygen species (ROS) accumulation and mitochondrial damage, which not only affect the metabolic processes of immune cells and pathological changes in fibroblastic synovial cells but also upregulate the expression of several inflammatory pathways, ultimately promoting inflammation. Additionally, ROS and mitochondrial damage are involved in angiogenesis and bone destruction, thereby accelerating RA progression. In this review, we highlighted the effects of ROS accumulation and mitochondrial damage on inflammatory response, angiogenesis, bone and cartilage damage in RA. Additionally, we summarized therapies that target ROS or mitochondria to relieve RA symptoms and discuss the gaps in research and existing controversies, hoping to provide new ideas for research in this area and insights for targeted drug development in RA.

Kurarinone attenuates hydrogen peroxide-induced oxidative stress and apoptosis through activating the PI3K/Akt signaling by upregulating IGF1 expression in human ovarian granulosa cells

Dysregulated follicular development may lead to follicular atresia, and this is associated with oxidative stress in granulosa cells. Kurarinone is a natural compound possessing multiple activities, including antioxidative ability. However, the role of kurarinone in granulosa cell damage during follicular atresia remains unknown. Human ovarian granulosa KGN cells were treated with hydrogen peroxide (H₂ O₂ ) to induce cellular damage. Cytotoxicity was investigated by lactate dehydrogenase (LDH) release assay. Oxidative stress was evaluated by detection of reactive oxygen species (ROS) generation and oxidative biomarker levels. Cell apoptosis was evaluated by flow cytometry, a Cell Death Detection ELISA Kit, and a Caspase-3 Assay Kit. The downstream target and related signaling pathway were analyzed by western blotting. Kurarinone attenuated H₂ O₂ -induced LDH release in KGN cells. Kurarinone relieved H₂ O₂ -induced increase in ROS generation and malondialdehyde level as well as decrease in superoxide dismutase-1 activity and heme oxygenase 1 and NAD(P)H quinone dehydrogenase 1 mRNA levels. Kurarinone inhibited H₂ O₂ -induced apoptosis in KGN cells. Kurarinone targeted insulin-like growth factor 1 (IGF1) and upregulated IGF1 expression to activate the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling. IGF1 silencing attenuated the suppressive effects of kurarinone on H₂ O₂ -induced oxidative stress and apoptosis in KGN cells. In conclusion, kurarinone attenuates H₂ O₂ -induced oxidative stress and apoptosis in KGN cells through activating the PI3K/Akt signaling by upregulating IGF1 expression, indicating the therapeutic potential of kurarinone in follicular atresia.

Kurarinone alleviates hemin-induced neuroinflammation and microglia-mediated neurotoxicity by shifting microglial M1/M2 polarization via regulating the IGF1/PI3K/Akt signaling

Cerebral hemorrhage is a fatal disease that causes severe damage to local nerve function. The purpose of this research is to analyze the effect of kurarinone on hemin-induced neuroinflammation and neurotoxicity. In our study, according to the results of bioinformatics analysis, we hypothesized that kurarinone might modulate cerebral hemorrhage advancement via the insulin-like growth factor 1/phosphoinositide 3-kinase/protein kinase B (IGF1/PI3K/Akt) signaling. Kurarinone promoted M2 microglia polarization, and curbed M1 polarization and inflammation in human microglial cells (HMC3) cells with hemin treatment. Besides, kurarinone upregulated IGF1 expression and activated the PI3K/Akt signaling pathway in hemin-treated HMC3 cells. In addition, downregulation of IGF1 or inhibition of the PI3K/Akt signaling weakened the effects of kurarinone on microglia polarization and inflammation in HMC3 cells with hemin treatment. Kurarinone alleviated apoptosis and oxidative damage of SH-SY5Y cells co-cultured with hemin-treated HMC3 cells. In conclusion, kurarinone lessened hemin-induced neuroinflammation and microglia-mediated neurotoxicity by regulating microglial polarization through modulating the IGF1/PI3K/Akt signaling. These results delivered a new prospective therapeutic drug for the treatment of cerebral hemorrhage.

Microbiota-assisted therapy for systemic inflammatory arthritis: advances and mechanistic insights

Research on the influence of gut microbiota on systemic inflammatory arthritis has exploded in the past decade. Gut microbiota changes may be a crucial regulatory component in systemic inflammatory arthritis. As a result of advancements in the field, microbiota-assisted therapy has evolved, but this discipline is still in its infancy. Consequently, we review the limitations of current systemic inflammatory arthritis treatment, analyze the connection between the microbiota and arthritis, and summarize the research progress of microbiota regulating systemic inflammatory arthritis and the further development aspects of microbiota-assisted therapy. Finally, the partial mechanisms of microbiota-assisted therapy of systemic inflammatory arthritis are being discussed. In general, this review summarizes the current progress, challenges, and prospects of microbiota-assisted therapy for systemic inflammatory arthritis and points out the direction for the development of microbiota-assisted therapy in the future.

Network Pharmacology Analysis and Experimental Validation to Investigate the Mechanism of Total Flavonoids of Rhizoma Drynariae in Treating Rheumatoid Arthritis

Objective

The study aimed to explore the mechanism of total flavonoids of Rhizoma Drynariae (TFRD) in the treatment of rheumatoid arthritis (RA) based on network pharmacology and experimental validation.

Methods

The active components of TFRD were identified from TCMSP and TCMID databases. Relevant targets of the active compounds of TFRD and RA-related targets were predicted by public databases online. A component-target (C-T) regulatory network was constructed by Cytoscape. The genes of TFRD regulating RA were imported into STRING database to construct a protein-protein interaction (PPI) network in order to predict the key targets. KEGG enrichment analysis was performed to predict the crucial mechanism of TFRD against RA. The active components of TFRD underwent molecular docking with the key proteins. Collagen-induced arthritis (CIA) model of rats and inflammatory factors-stimulated fibroblast-like synoviocytes were used in vivo and in vitro to validate the efficacy and predicted critical mechanisms of TFRD.

Results

Network Pharmacology analysis revealed that TFRD had 14 active compounds, corresponding to 213 targets, and RA related to 2814 genes. There were 137 intersection genes between TFRD and RA. KEGG indicated that therapeutic effects of TFRD on RA involves T cell receptor signaling pathway, Th17 cell differentiation, IL-17 signaling pathway, TNF signaling pathway, MAPK signaling pathway and PI3K/AKT signaling pathway. In vivo experiments suggested TFRD can alleviate the inflammatory response, joint swelling and synovial abnormality of CIA rats. TFRD contributed to the decrease of Th17 cells and the down-regulated secretion of IL-17A and TNF-α of activated lymphocyte in CIA model. In vitro experiments confirmed TFRD can effectively inhibit the inflammatory response of fibroblast-like synoviocytes and suppress the abnormal activation of MAPK, PI3K/AKT and NFκB signaling pathways.

Conclusion

The treatment of RA with TFRD is closely related to inhibiting Th17 differentiation and inflammatory response of synoviocytes.

Sophoraflavanone G from Sophora flavescens Ameliorates Allergic Airway Inflammation by Suppressing Th2 Response and Oxidative Stress in a Murine Asthma Model

Sophoraflavanone G (SG), isolated from Sophora flavescens, has anti-inflammatory and anti-tumor bioactive properties. We previously showed that SG promotes apoptosis in human breast cancer cells and leukemia cells and reduces the inflammatory response in lipopolysaccharide-stimulated macrophages. We investigated whether SG attenuates airway hyper-responsiveness (AHR) and airway inflammation in asthmatic mice. We also assessed its effects on the anti-inflammatory response in human tracheal epithelial cells. Female BALB/c mice were sensitized with ovalbumin, and asthmatic mice were treated with SG by intraperitoneal injection. We also exposed human bronchial epithelial BEAS-2B cells to different concentrations of SG to evaluate its effects on inflammatory cytokine levels. SG treatment significantly reduced AHR, eosinophil infiltration, goblet cell hyperplasia, and airway inflammation in the lungs of asthmatic mice. In the lungs of ovalbumin-sensitized mice, SG significantly promoted superoxide dismutase and glutathione expression and attenuated malondialdehyde levels. SG also suppressed levels of Th2 cytokines and chemokines in lung and bronchoalveolar lavage samples. In addition, we confirmed that SG decreased pro-inflammatory cytokine, chemokine, and eotaxin expression in inflammatory BEAS-2B cells. Taken together, our data demonstrate that SG shows potential as an immunomodulator that can improve asthma symptoms by decreasing airway-inflammation-related oxidative stress.

Toxic Effects of Endocrine Disruptor Exposure on Collagen-Induced Arthritis

Endocrine disruptors (EDs) are chemical substances capable of affecting endocrine system functioning and interfering with organ morphogenesis and physiological functions. The development and regeneration of bone tissues have a complex hormonal regulation, and therefore, bone tissue cells can be considered potential targets for endocrine disruptors. In that regard, the aim of this research was to investigate the impact of ED exposure on the inflammatory response and oxidative stress in an experimental model of collagen-induced arthritis (CIA). Arthritis was induced by an emulsion of type II collagen (CII) and complete Freund’s adjuvant, which was administered intradermally on days 0 and 21. Mice from day 21 to day 35 received the following EDs by oral gavage: cypermethrin (CP), diethyl phthalate (DEP), vinclozolin (VCZ), 17α-ethinylestradiol (EE), perfluorooctanesulfonic acid (PFOS) and atrazine (ATR). ED exposure caused worsening of clinical signs (erythema and edema in the hind paws), histological and radiographic changes, as well as behavioral deficits, induced by CII injections. Furthermore, ED exposure significantly increased the degree of inflammation and oxidative damage induced by arthritis; this upregulation was more evident after exposure to ATR than to other EDs. The results from our study suggest that exposure to EDs may play a deleterious role in the progression of RA; therefore, exposure to EDs should be limited.

Recent Advances in Understanding Nrf2 Agonism and Its Potential Clinical Application to Metabolic and Inflammatory Diseases

Oxidative stress is a major component of cell damage and cell fat, and as such, it occupies a central position in the pathogenesis of metabolic disease. Nuclear factor-erythroid-derived 2-related factor 2 (Nrf2), a key transcription factor that coordinates expression of genes encoding antioxidant and detoxifying enzymes, is regulated primarily by Kelch-like ECH-associated protein 1 (Keap1). However, involvement of the Keap1–Nrf2 pathway in tissue and organism homeostasis goes far beyond protection from cellular stress. In this review, we focus on evidence for Nrf2 pathway dysfunction during development of several metabolic/inflammatory disorders, including diabetes and diabetic complications, obesity, inflammatory bowel disease, and autoimmune diseases. We also review the beneficial role of current molecular Nrf2 agonists and summarize their use in ongoing clinical trials. We conclude that Nrf2 is a promising target for regulation of numerous diseases associated with oxidative stress and inflammation. However, more studies are needed to explore the role of Nrf2 in the pathogenesis of metabolic/inflammatory diseases and to review safety implications before therapeutic use in clinical practice.

Extracts of Waste from Poplar Wood Processing Alleviate Experimental Dextran Sulfate-Induced Colitis by Ameliorating Oxidative Stress, Inhibiting the Th1/Th17 Response and Inducing Apoptosis in Inflammatory Lymphocytes

As a fast-growing tree, poplar is widely planted and typically used for wood processing in China. During poplar wood processing, a large amount of poplar sawdust (PS) and poplar leaves (PL) are produced and abandoned. To make full use of poplar resources and clarify the use of poplar as a feed additive, the active ingredients in PS and PL were extracted and isolated, and the anti-inflammatory effects of the extracts on mice with dextran sulfate sodium (DSS)-induced colitis were investigated. In vitro anti-inflammatory experiments showed that the ethyl acetate extract of PS and PL (PSE and PLE, respectively) could significantly inhibit the proliferation of concanavalin A (Con A)-activated lymphocytes. Salicortin, tremulacin and salireposide were identified in both PSE and PLE. Oral administration of PSE and PLE rescued DSS-induced colonic shortening, repaired tissue damage, and decreased the disease activity index (DAI). The antioxidant capacity, including the increased activities of glutathione peroxidase (GSH-Px), total superoxide dismutase (T-SOD and catalase (CAT) and decreased activity of myeloperoxidase (MPO), in the colons of mice with colitis was enhanced through the activation of ERK after treatment with PSE and PLE. The ratio of Th1 to Th17 cells, which can lead to inflammation in the spleen, was significantly decreased by the administration of PSE and PLE, while the phosphorylation of related transcription factors (p65, STAT1, and STAT3) was inhibited. Furthermore, PSE and PLE could induce apoptosis in Con A-activated lymphocytes, which may be associated with the increase in p-TBK1, as the molecular docking results also indicated that salireposide in PSE and PLE could interact with the TBK1 protein. Overall, our study provides a promising feed additive for improving intestinal inflammation in animals and a method for the full utilization of poplar resources.

Five-Decade Update on Chemopreventive and Other Pharmacological Potential of Kurarinone: a Natural Flavanone

In the present article we present an update on the role of chemoprevention and other pharmacological activities reported on kurarinone, a natural flavanone (from 1970 to 2021). To the best of our knowledge this is the first and exhaustive review of kurarinone. The literature was obtained from different search engine platforms including PubMed. Kurarinone possesses anticancer potential against cervical, lung (non-small and small), hepatic, esophageal, breast, gastric, cervical, and prostate cancer cells. In vivo anticancer potential of kurarinone has been extensively studied in lungs (non-small and small) using experimental xenograft models. In in vitro anticancer studies, kurarinone showed IC₅₀ in the range of 2–62 µM while in vivo efficacy was studied in the range of 20–500 mg/kg body weight of the experimental organism. The phytochemical showed higher selectivity toward cancer cells in comparison to respective normal cells. kurarinone inhibits cell cycle progression in G2/M and Sub-G1 phase in a cancer-specific context. It induces apoptosis in cancer cells by modulating molecular players involved in apoptosis/anti-apoptotic processes such as NF-κB, caspase 3/8/9/12, Bcl2, Bcl-XL, etc. The phytochemical inhibits metastasis in cancer cells by modulating the protein expression of Vimentin, N-cadherin, E-cadherin, MMP2, MMP3, and MMP9. It produces a cytostatic effect by modulating p21, p27, Cyclin D1, and Cyclin A proteins in cancer cells. Kurarinone possesses stress-mediated anticancer activity and modulates STAT3 and Akt pathways. Besides, the literature showed that kurarinone possesses anti-inflammatory, anti-drug resistance, anti-microbial (fungal, yeast, bacteria, and Coronavirus), channel and transporter modulation, neuroprotection, and estrogenic activities as well as tyrosinase/diacylglycerol acyltransferase/glucosidase/aldose reductase/human carboxylesterases 2 inhibitory potential. Kurarinone also showed therapeutic potential in the clinical study. Further, we also discussed the isolation, bioavailability, metabolism, and toxicity of Kurarinone in experimental models.