Effect of umbelliferone on adjuvant-induced arthritis in rats by MAPK/NF-κB pathway

Nitazoxanide alleviates CFA-induced rheumatoid arthritis in Wistar rats by modulating the STAT-3 and NF-κB pathways

Background and Objective

Rheumatoid arthritis (RA) is a chronic autoimmune condition characterized by joint pain and inflammation. RA involves elevated expression of nuclear factor kappa B (NF-κB), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α), which drive synovial inflammation and joint destruction primarily through the STAT-3 signalling pathway. Nitazoxanide (NTZ) has been shown in previous studies to inhibit the signalling of STAT-3.

Methods

This study evaluated the anti-arthritic effects of NTZ in a rat model of complete Freund's adjuvant (CFA) induced arthritis. NTZ was administered orally at doses of 400, 200, and 100 mg/kg over 28 days. Various parameters, including changes in paw swelling, body weight, arthritic index, haematological measurements, levels of inflammatory cytokines, and histopathological analysis, were monitored.

Results

NTZ treatment significantly improved body weight and reduced paw swelling, edema, and the arthritic index in CFA-induced arthritic rats. The treatment also decreased white blood cell counts while increasing red blood cell and haemoglobin levels. NTZ effectively modulated inflammatory cytokine levels and showed improvement in the histopathology of the ankle joints.

Conclusion

NTZ exhibited significant anti-arthritic activity through the inhibition of the STAT-3 and NF-κB pathways, emphasizing its potential as a therapeutic option for rheumatoid arthritis.

Umbelliferone reduces inflammation and ligature-induced osteoclastic alveolar bone resorption in mice

AIMS

This study aimed to investigate the effects of Umbelliferone (UMB) on the inflammation underlying alveolar bone resorption in mouse periodontitis.

METHODS

Male Swiss mice subjected to a ligature of molars were grouped as non-treated (NT), received UMB (15, 45, or 135 mg/kg) or saline daily for 7 days, respectively, and were compared with naïve mice as control. Gingival tissues were evaluated by myeloperoxidase (MPO) activity and interleukin-1β level by ELISA. The bone resorption was directly assessed on the region between the cement-enamel junction and the alveolar bone crest. Microscopically, histomorphometry of the furcation region, immunofluorescence for nuclear factor-kappa B (NF-ĸB), and immunohistochemistry for tartrate-resistant acid phosphatase (TRAP), and cathepsin K (CTSK) were performed. Systemically, body mass variation and leukogram were analyzed.

RESULTS

Periodontitis significantly increased MPO activity, interleukin-1β level, and NF-ĸB+ immunofluorescence, and induced severe alveolar bone and furcation resorptions, besides increased TRAP+ and CTSK+ cells compared with naïve. UMB significantly prevented the inflammation by reducing MPO activity, interleukin-1β level, and NF-ĸB+ intensity, besides reduction of resorption of alveolar bone and furcation area, and TRAP+ and CTSK+ cells compared with the NT group. Periodontitis or UMB treatment did not affect the animals systemically.

CONCLUSION

UMB improved periodontitis by reducing inflammation and bone markers.

Umbelliferon: a review of its pharmacology, toxicity and pharmacokinetics

Coumarin, a plant secondary metabolite, has various pharmacological activities, including antioxidant stress and anti-inflammatory effects. Umbelliferone, a common coumarin compound found in almost all higher plants, has been extensively studied for its pharmacological effects in different disease models and doses with complex action mechanisms. This review aims to summarize these studies and provide useful information to relevant scholars. The pharmacological studies demonstrate that umbelliferone has diverse effects such as anti-diabetes, anti-cancer, anti-infection, anti-rheumatoid arthritis, neuroprotection, and improvement of liver, kidney, and myocardial tissue damage. The action mechanisms of umbelliferone include inhibition of oxidative stress, inflammation, and apoptosis, improvement of insulin resistance, myocardial hypertrophy, and tissue fibrosis, in addition to regulation of blood glucose and lipid metabolism. Among the action mechanisms, the inhibition of oxidative stress and inflammation is the most critical. In short, these pharmacological studies disclose that umbelliferone is expected to treat many diseases, and more research should be conducted.

Cassia absus-mediated upregulation of IL-4, IL-10 and downregulation of IL-1β, IL-6, TNF- α, NF-κB, IFN-γ in CFA-induced arthritis model

Traditional use of Cassia absus as an anti-inflammatory in conjunctivitis and bronchitis is well reported. Owing to its anti-inflammatory potential, the current study appraised in vivo anti-arthritic activity of n-hexane and aqueous extracts of Cassia absus seeds (200 mg/kg) using Complete Freund's Adjuvant (CFA) rat model of arthritis. Changes in paw size (mm), joint diameter (mm), and pain response (sec) were recorded at the baseline and then after CFA induction at the interval of 4 days till the 28th day. Blood samples of anesthetized rats were collected for the estimation of hematological, oxidative, and inflammatory biomarkers. Results showed percent inhibition in paw edema (45.09% and 60.79%) with both n-hexane and aqueous extracts, respectively. Significant reduction in paw size and ankle joint diameter (P < 0.01) was seen in extracts treated rats. Erythrocyte Sedimentation rate, C-Reactive Protein, White Blood Cell levels significantly lowered, and Hemoglobin, Platelets and Red Blood Cell count significantly increased post-treatments. Superoxide Dismutase, Catalase, and Glutathione were significantly improved (P < 0.0001) in treated groups as compared to CFA induced arthritic control. Real-time polymerase chain reaction investigation showed significant downregulation (P < 0.05) of Interleukin-1β, Tumor Necrosis Factor-α, Interleukin-6, Cycloxygenase-2, Nuclear Factor-κB, Prostaglandin E Synthase 2, Interferon Gamma and upregulation of Interleukin-4, Interleukin-10 in both n-hexane and aqueous extract-treated groups. It is thereby concluded that Cassia absus can significantly attenuate CFA-induced arthritis by modulation of oxidative and inflammatory biomarkers.

Ovotransferrin alleviated acute gastric mucosal injury in BALB/c mice caused by ethanol

Acute gastric mucosal injury is a common gastrointestinal disorder, which influences patients' life quality. It was found that ovotransferrin (OVT) reduces the abundance of Helicobacter pylori associated with gastric disease in the intestine of immunosuppressed mice. To clarify its gastric protective function, the present study investigated the effect of OVT on BALB/c mice with ethanol-induced gastric mucosal injury. Results showed that OVT attenuated the ethanol-induced gastric mucosal injury. Furthermore, OVT effectively downregulated the expression of inflammatory markers (tumor necrosis factor-α, interleukin (IL)-1β and IL-6) but enhanced the secretion of IL-4, IL-10 and prostaglandin E2. And OVT pretreatment significantly inhibited the activation of the MAPK/NF-κB pathway. Additionally, OVT improved gastric antioxidant ability by increasing superoxide dismutase and glutathione levels and decreasing malondialdehyde and myeloperoxidase content. Pretreatment with OVT modulated the equilibrium between B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X. The above results indicated that OVT alleviated inflammatory responses, oxidative stress and apoptosis in gastric mucosal injury mice caused by ethanol.

Cassia alata, Coriandrum sativum, Curcuma longa and Azadirachta indica: Food Ingredients as Complementary and Alternative Therapies for Atopic Dermatitis-A Comprehensive Review

Traditional medicine is critical in disease treatment and management. Herbs are gaining popularity for disease management and treatment. Therefore, they can be utilised as complementary and alternative treatment (CAT) ingredients. Atopic dermatitis (AD) is one of the common non-communicable diseases. It is characterised by chronic inflammatory skin disease with intense pruritus and eczematous lesions. AD is associated with oxidative stress, microbial infection, and upregulation of inflammatory cytokines. Both children and adults could be affected by this skin disorder. The prevalence of AD is increasing along with the country’s level of development. This review revisited the literature on four medicinal herbs widely used as complementary medicine to manage AD. These therapeutic herbs are commonly eaten as food and used as spices in Asian cuisine. The four food herbs reviewed are Cassia alata, Coriandrum sativum, Curcuma longa Linn, and Azadirachta indica. Their traditional uses and phytochemical content will be covered. Four relevant pharmacological and biological activities of the plants crucial in AD management have been reviewed and discussed, including anti-inflammatory, anti-microbial, antioxidant, and wound recovery.

Umbelliferone Inhibits Migration, Invasion and Inflammation of Rheumatoid Arthritis Fibroblast-Like Synoviocytes and Relieves Adjuvant-Induced Arthritis in Rats by Blockade of Wnt/β-Catenin Signaling Pathway

Umbelliferone (UMB), a natural coumarin compound, has been reported to possess anti-rheumatic effects on rheumatoid arthritis (RA) experimental models, but its potential role of UMB in regulating migration, invasion and inflammation of RA fibroblast-like synoviocytes (FLS) remain unclear. Herein, MTT assay was performed to confirm the non-cytotoxic concentrations (10, 20, and 40[Formula: see text][Formula: see text]M) and the treatment time (24[Formula: see text]h) of UMB on TNF-[Formula: see text]-stimulated RA FLS (MH7A cells) in vitro. Results of wound-healing, transwell and phalloidin staining assays revealed that UMB inhibited TNF-[Formula: see text]-induced migration, invasion and F-actin cytoskeletal reorganization in MH7A. Results of ELISA, western blot and gelatin zymography indicated that UMB decreased the productions of pro-inflammatory factors, including IL-1[Formula: see text], IL-6, IL-8, MMP-2 and MMP-9, and inhibited MMP-2 activity in TNF-[Formula: see text]-stimulated MH7A cells. In vivo, UMB (25[Formula: see text]mg/kg and 50[Formula: see text]mg/kg) relieved the joint damage and synovial inflammation in rats with adjuvant-induced arthritis (AIA). Mechanistically, UMB could suppress Wnt/[Formula: see text]-catenin signaling both in TNF-[Formula: see text]-induced MH7A cells and in AIA rat synovium, evidenced by decreasing Wnt1 protein level, activating GSK-3[Formula: see text] kinase by blocking GSK-3[Formula: see text] (Ser9) phosphorylation, and reducing the protein level and nuclear translocation of [Formula: see text]-catenin. Importantly, combined use of lithium chloride (a Wnt/[Formula: see text]-catenin signaling agonist) eliminated the inhibitory effects of UMB on migration, invasion and inflammation in vitro and the anti-arthritic effects of UMB in vivo. We concluded that UMB inhibited TNF-[Formula: see text]-induced migration, invasion and inflammation of RA FLS and attenuated the severity of rat AIA through its ability to block Wnt/[Formula: see text]-catenin signaling pathway.

Umbelliferone and scopoletin target tyrosine kinases on fibroblast-like synoviocytes to block NF-κB signaling to combat rheumatoid arthritis

Rheumatoid arthritis (RA) is a complex autoimmune condition primarily affecting synovial joints, which targeted synthetic drugs have damaging safety issues. Saussurea laniceps, a reputed anti-rheumatic medicinal herb, is an excellent place to start looking for natural products as safe, effective, targeted therapeutics for RA. Via biomimetic ultrafiltration, umbelliferone and scopoletin were screened as two anti-rheumatic candidates with the highest specific affinities towards the membrane proteomes of rheumatic fibroblast-like synoviocytes (FLS), the pivotal effector cells in RA. In vitro assays confirmed that the two compounds, to varying extents, inhibited RA-FLS proliferation, migration, invasion, and NF-κB signaling. Network pharmacology analysis and molecular docking analysis jointly revealed that umbelliferone and scopoletin act on multiple targets, mostly tyrosine kinases, in combating RA. Taken together, our present study identified umbelliferone and scopoletin as two major anti-rheumatic components from SL that may bind and inhibit tyrosine kinases and subsequently inactivate NF-κB in RA-FLSs. Our integrated drug discovery strategy could be valuable in finding other multi-target bioactive compounds from complex matrices for treating multifactorial diseases.

Systematic review of preclinical studies about effects of Coriandrum sativum L. on inflammatory mediators

This study is designed to systematically review the accessible researches regarding influence of Coriandrum sativum L. on inflammatory mediators including interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). Databases Scopus, PubMed, WOS, ProQuest, and a Google Scholar were searched until February 2022 and search alerts were turned on to find papers published following the primary search. There was not any restriction in language and/or date. No human study was gained; thus, animal and in vitro researches were considered. The references of related papers were reviewed to access plausible researches. Twenty-four papers were entered in review. Inflammatory factors IL-1β, IL-6, and TNF-α considerably had a descending direction following C. sativum consumption. In other words, the pooled direction of influences was consistently lower for inflammatory mediators in 7 of 9 in vitro and 10 of 16 animal investigations. These results demonstrated the potential of C. sativum in reducing IL-1β, IL-6, and TNF-α. C. sativum is hopeful but not yet a confirmed natural ingredient to reduce systemic inflammation in subjects with inflammation-prone disorders. Additional investigations are required to concentrate on assessing the impact of C. sativum on inflammatory factors that are not exceedingly fluctuating and the clinical consequences of inflammation-linked diseases.

Investigation of the active ingredients and pharmacological mechanisms of Porana sinensis Hemsl. Against rheumatoid arthritis using network pharmacology and experimental validation

Background

Porana sinensis Hemsl. has been widely used as a substitute for Erycibes Caulis to treat rheumatoid arthritis (RA) in traditional Chinese medicine (TCM). However, little is known about the active ingredients and pharmacological mechanisms that mediate the action of P. sinensis against RA.

Methods

The compounds contained in P. sinensis were analyzed by Q Exactive Focus mass spectrometer. The active constituents and pharmacological mechanism of P. sinensis against RA were clarified using a network pharmacology-based investigation. LPS-induced RAW 264.7 cells was used to verify anti-inflammatory effects of the active compounds screened by network pharmacology. Collagen-induced arthritis model was used to further investigate the mechanism of P. sinensis against RA.

Results

The potential components and targets of P. sinensis against RA were analyzed using network pharmacology, and five compounds, twenty-five targets, and eight pathways were identified. Experimental validation suggested that P. sinensis extract and five compounds (esculetin, umbelliferone, trans-N-feruloyltyramine, caffeic acid and scopolin) could inhibit the release of inflammatory mediators (NO, TNF-α, IL-1β and IL-6) in LPS-induced RAW 264.7 cell. P. sinensis extract attenuated the severity, pathological changes, and release of cytokines (IL-6 and HIF-1α) during RA progression by regulating the PI3K/AKT and HIF-1 pathways.

Conclusion

The study provides a basis for the application of P. sinensis against RA. Our findings may provide suggestions for developing P. sinensis into a substitute for Erycibes Caulis.

7-Hydroxycoumarin mitigates the severity of collagen-induced arthritis in rats by inhibiting proliferation and inducing apoptosis of fibroblast-like synoviocytes via suppression of Wnt/β-catenin signaling pathway

BACKGROUND

7-Hydroxycoumarin (7-HC) as a coumarin compound is widely found in Chinese herbs and exhibits diverse biological activities. Promoting cell apoptosis of fibroblast-like synoviocytes (FLS) is a meaningful strategy for rheumatoid arthritis (RA). Though the protective effect of 7-HC on RA experimental models has been reported, the specific mechanisms, especially the possible relationships of this effect to regulating FLS proliferation and apoptosis, still need clarification.

PURPOSE

This study clarified the therapeutic effects of 7-HC on collagen-induced arthritis (CIA) in rats and explored the underlying mechanisms.

METHODS

In vivo, 7-HC (15, 30 or 60 mg/kg) was intraperitoneally given to CIA rats, and its therapeutic effect and anti-inflammatory activity were evaluated. Ki67 immunohistochemistry, TUNEL assay and synovial proteins detection were conducted. In vitro, after treating with 7-HC (20, 40 or 80 μM) in TNF-α-stimulated RA FLS (MH7A cell line), cell proliferation and apoptosis were examined. The involvement of Wnt/β-catenin pathway was checked in vivo and in vitro.

RESULTS

7-HC attenuated the severity of rat CIA, evidenced by the reduction of paw swelling, arthritis index, joint damage, collagen type II antibody serum level, and IL-1β, IL-6, TNF-α production in serum and synovium. Particularly, 7-HC in vivo had anti-proliferative and pro-apoptotic effects on CIA rat synovial cells, indicated by reduced synovial Ki67 expression, raised synovial apoptosis index, decreased Bcl-2 protein level and increased level of Bax and cleaved caspase 3 protein. Further, 7-HC in vitro suppressed proliferation and promoted apoptosis of TNF-α-stimulated MH7A cells by regulating the mitochondrial pathway. Mechanistically, 7-HC treatment inhibited Wnt/β-catenin pathway, suggested by the reduction of pathway-related proteins (e.g. Wnt1, LRP6, p-GSK-3β (Ser9), β-catenin, cyclin D1 and c-Myc), the recovery of GSK-3β activity and the inhibition of β-catenin nuclear translocation. As expected, combined use of lithium chloride, an activator of Wnt/β-catenin signaling, reversed the anti-proliferative and pro-apoptotic effects of 7-HC in vitro.

CONCLUSION

7-HC relieved the severity of rat CIA by inhibiting cell proliferation and inducing apoptosis of rheumatoid FLS via inhibition of Wnt/β-catenin pathway.

Anti-allergic activities of Umbelliferone against histamine- and Picryl chloride-induced ear edema by targeting Nrf2/iNOS signaling in mice

BACKGROUND

The current study was aimed to investigate the anti-allergic activities of the Umbelliferone (UMB) against the acute Histamine and chronic Picryl chloride (PiCl)-induced allergy in mice. UMB is a coumarin derivative (isolated from Angelica decursiva) found in various parts of the plants such as flowers, roots and, stems isolated from the plants of Umbelliferae family.

METHODS

The UMB (1, 10, 50 mg/kg) was administered intraperitoneally (i.p) half an h before or 2 h after the induction of allergic ear edema. The acute ear edema was induced by histamine (intradermally, i.d), while the chronic ear edema was induced by painting the PiCl (sensitized with the toluene) on the ear. The antioxidants and oxidative stress markers were assessed. The histological changes were assessed using Hematoxylin and eosin (H and E) and giemsa staining. The immunohistochemistry studies were performed to assess the expression of the nuclear factor erythroid 2-related factor 2 (Nrf2) and inducible nitric oxide synthase (iNOS). The data was analyzed using one-way ANOVA tests followed by Tukey's test with p < 0.05 was chosen as criteria for statistical significance.

RESULTS

UMB treatment markedly reduced the allergic ear edema and ear weight compared to the negative control. Furthermore, the UMB attenuated the oxidative stress markers, while induced the antioxidants enzymes. Similarly, the UMB treatment significantly attenuated the serum immunoglobulin E (IgE) level. The UMB treatment markedly improved the histological parameters using H and E staining and Giemsa staining. The UMB administration induced the Nrf2 expression, while attenuated the iNOS expression. Furthermore, the computational analysis was performed to assess the interaction of the UMB with the various protein targets and to determine the mechanism of interaction with the target proteins.

CONCLUSION

In conclusion, the UMB treatment significantly alleviated the allergic symptoms, attenuating the oxidative stress, improved the histological features using in vivo and computational approaches.

Design, synthesis, and SAR study of novel 4,5-dihydropyrazole-Thiazole derivatives with anti-inflammatory activities for the treatment of sepsis

Systemic inflammatory response syndrome is a major feature of sepsis which is one of the major causes of death worldwide. It has been reported that 3,5-diaryl-4,5-dihydropyrazole and thiazole derivatives have many biological functions, especially in the aspect of anti-inflammation. According to the strategy of pharmacophore combination, we introduced thiazole moiety into dihydropyrazole skeleton to design and synthesize a novel series of 2-(3,5-diphenyl-4,5-dihydro-1H-pyrazol-1-yl)-4-methylthiazole derivatives, and evaluated their anti-inflammatory activities for sepsis treatment. Preliminary structure-activity relationship (SAR) analysis was conducted by their inhibitory activities against nitric oxide (NO) release in LPS-induced RAW264.7 cells, and the optimal compound E26 exhibited more potent anti-inflammatory activity than the positive control treatment indomethacin and dexamethasone. In further mechanism study, our results showed that compound E26 significantly suppressed the production of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), NO and inhibited the expressions of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) through blocking MAPKs signaling pathway. In addition, in vivo administration of compound E26 resulted in a significant improvement of LPS-induced sepsis in C57BL/6J mice, with reducing toxicity in multiple organs. Taken together, this study demonstrated the compound E26 could be a promising agent for the treatment of sepsis.

Potency of Bone Marrow-Derived Mesenchymal Stem Cells and Indomethacin in Complete Freund's Adjuvant-Induced Arthritic Rats: Roles of TNF-α, IL-10, iNOS, MMP-9, and TGF-β1

Rheumatoid arthritis (RA) is an autoimmune syndrome affecting joint spaces, leading to the disabled state. Currently, there is no optimal therapy for RA except for systemic immunosuppressants that have variable undesirable effects after long-term use. Hence, the need for other treatment modalities has emerged in an attempt to develop a treating agent that is effective but without bad effects. Bone marrow-derived mesenchymal stem cells (BM-MSCs) may be an alternative medicine since they may differentiate into a variety of mesenchymal tissues including bone and cartilage. Indomethacin (IMC) could be suggested as an analgesic, anti-inflammatory, and antirheumatic potential agent against the course of RA since it possesses significant palliative effects and antipyretic properties. Therefore, our target of this study was to explore and compare the effect of BM-MSCs (1 × 106 cells/rat at the 1st, 6th, 12th, and 18th days) and IMC (2 mg/kg b.w./day for 3 weeks) either alone or in combination on arthritic rats. The model of rheumatoid arthritis in rats was induced by subcutaneous injection of 0.1 mL/rat CFA into the footpad of the right hind paw. The BM-MSC intravenous injection and IMC oral administration significantly reduced the elevated right hind leg paw diameter and circumference, serum anti-CCP, and ankle joint articular tissue expressions of TNF-α, iNOS, MMP-9, and TGF-β1 while they significantly increased the lowered articular IL-10 expression in CFA-induced arthritic rats. The combinatory effect of the two treatments was the most potent. In conclusion, the treatment of RA with BM-MSCs and IMC together is more effective than the treatment with either BM-MSCs or IMC. The Th1 cytokine (TNF-α), Th2 cytokine (IL-10), iNOS, MMP-9, and TGF-β1 are important targets for mediating the antiarthritic effects of BM-MSCs and IMC in CFA-induced arthritis in rats.

Asphodelus tenuifolius extracts arrested inflammation and arthritis through modulation of TNF-α, NF-κB, ILs, and COX-2 activities in in vivo models

Asphodelus tenuifolius is traditionally used in the management of rheumatic pain and inflamed body parts. The current study validated its traditional use as an anti-arthritic and anti-inflammatory agent using a series of in vivo models. Carrageenan and histamine-induced acute oedema models were employed to study the effects of n-hexane (n-HeAT) and ethanolic (EeAT) extracts on acute inflammatory mediators and were found to inhibit oedema formation in a dose-dependent manner. Formalin and complete Freund's adjuvant (CFA) were injected into the hind paw of rats for the induction of arthritis. In the formalin model both n-HeAT and EeAT showed significantly better (p < 0.05) anti-oedema effects from day 6 onward. In CFA model rats were treated on 8th day of induction with extracts at the doses of 250, 500, and 750 mg/kg respectively. Piroxicam (10 mg/kg) and normal saline (10 mL/kg) were used as positive and negative controls respectively. Both n-HeAT and EeAT significantly (p < 0.05) decreased arthritis development in a time-dependent manner and at 28th day extent of inflammation was even less than that observed at day 8. The arthritic score was measured at day 12, 16, 20, 24, and 28 and was observed to be significantly less (p < 0.05) in animals treated with 750 mg/kg of n-HeAT and EeAT, respectively. Joint inflammation (p < 0.01), bone erosion (p < 0.001) and, pannus formation (p < 0.01) were significantly declined in A. tenuifolius treatment groups. Radiographic evaluations (X-ray) were conducted to check bone integrity and extent of inflammation and were observed to be diminished at day 28 in A. tenuifolius extracts treated groups. HPLC was performed to screen the phytochemical profile of n-HeAT and EeAT and were found to contain flavonoids and phenolic compounds. Quantitative real-time polymerase chain reaction (qPCR) was performed to detect effects of n-HeAT and EeAT treatments on inflammatory markers i.e., IL-4, IL-6, IL-10, COX-2, NF-κB, and I-κB using blood samples. ELISA assays were performed for the detection of levels of C-reactive proteins, respectively. Significant downregulation of TNF-α, IL-4, IL-6, IL-1β, COX-2, NF-κB with simultaneous upregulation of IL-10 and I-κB was observed in n-HeAT and EeAT treatment groups. ELISA assays also showed significant (p < 0.05) down-modulation in the serum levels of CRP and TNF-α. Both extracts showed relatively weak antioxidant activities as compared with ascorbic acid in in vitro assay. Based on findings of the current study it is concluded that A. tenuifolius has anti-inflammatory and anti-arthritic effects and thus has potential to be used as an adjunct to standard NSAIDs therapy.Graphic abstract.

Umbelliferone attenuates gentamicin-induced renal toxicity by suppression of TLR-4/NF-κB-p65/NLRP-3 and JAK1/STAT-3 signaling pathways

Nephrotoxicity is the most common adverse effect of gentamicin (GNT). This study aimed to investigate the possible nephroprotective effect of umbelliferone (UMB), against GNT-induced nephrotoxicity. Rats were allocated into the control group; UMB group (50 mg/kg/day, P.O. for 15 days); GNT group (100 mg/kg/day, i.p., for 8 days); and GNT + UMB group. By the end of the experimental period, serum creatinine, urea, and uric acid as well as urine KIM-1 and urine albumin/creatinine ratio were evaluated to estimate kidney function. Moreover, tissue samples were collected for assessment of ERK1/2, p-ERK1/2, TLR-4, p38 MAPK, NF-κB-p65, NLRP-3, IkBα, TNF-α, IL-1β, JAK1, STAT-3, p-STAT, and cleaved caspase-3. In support, the histopathological examination of renal tissues was performed. UMB improves kidney function through regulation of renal serum biomarkers, with alleviations of histological abrasions induced by GNT. Besides, UMB downregulates renal protein expressions of ERK1/ERK2, TLR-4, and p38MAPK, with subsequent suppression of NF-κB-p65/NLRP-3 inflammasome and JAK1/STAT-3 pathways as well as cleaved caspase-3. In parallel, UMB induced IkBα upregulation. Collectively, UMB markedly amended all GNT-induced renal changes. These nephroprotective outcomes could be attributed to its ability to impede TLR-4/NF-κB-p65/NLRP-3 inflammasome and JAK1/STAT-3 pathways activation, as well as to its anti-inflammatory property.

7-Hydroxycoumarin Attenuates Colistin-Induced Kidney Injury in Mice Through the Decreased Level of Histone Deacetylase 1 and the Activation of Nrf2 Signaling Pathway

Colistin has been considered as the last line of defense against Gram-negative bacterial infections, however, the potential nephrotoxicity limited its clinical use. 7-Hydroxycoumarin (7-HC) possesses many beneficial pharmacological activities. This study aimed to investigate the nephroprotective effects of 7-HC against colistin-induced kidney injury. In vivo experiments showed that 7-HC alleviated kidney injury induced by colistin, as indicated by lower levels of serum neutrophil gelatinase-associated lipocalin, blood urea nitrogen and creatinine levels. Both in vivo and in vitro results demonstrated that 7-HC alleviated oxidative stress and apoptosis induced by colistin, as shown by decreased malondialdehyde levels, decreased caspase-3 and caspase-9 activities, and increased superoxide dismutase and catalase activities. We also found that colistin significantly induced histone deacetylase (HDAC) 1 expression that deacetylated histone 3 at Lys27 acetylation (H3K27AC) of Nrf2 promoter region and hence inhibiting Nrf2 signaling. 7-HC treatment restored histone acetylation at the Nrf2 promoter region and hence promoted Nrf2 expression. These results suggested that 7-HC alleviates colistin-induced renal injury and this effect was achieved by enhancement of renal antioxidant capacity with the decreased level of HDAC1 and the activation of Nrf2 signaling pathway.

Comprehensive Characterization of Secondary Metabolites from Colebrookea oppositifolia (Smith) Leaves from Nepal and Assessment of Cytotoxic Effect and Anti-Nf-κB and AP-1 Activities In Vitro

Here we report the comprehensive characterization of the secondary metabolites from the leaves of Colebrookea oppositifolia Smith, a species used as medicinal plant in the traditional medicine of Nepal. Phytochemical screening of bioactives was performed using an integrated LC-MSⁿ and high resolution MS (Mass Spectrometry) approach. Forty-three compounds were tentatively identified, mainly aglyconic and glycosilated flavonoids and phenolic acids, as well as other bioactives such as coumarins and terpenes were detected. Furthermore, the NF-κB and AP-1 inhibitory activity of C. oppositifolia extract were evaluated, as well as its cytotoxicity against THP-1 cells, in order to assess the potential use of this herb as a source of anti-inflammatory and cytotoxic compounds. The results so far obtained indicate that C. oppositifolia leaves extract could significantly reduce the viability of THP-1 cells (IC₅₀ = 6.2 ± 1.2 µg/mL), as well as the activation of both NF-κB and AP-1 at the concentration of 2 μg/mL. Our results indicate that Nepalese C. oppositifolia is a valuable source of anti-inflammatory and cytotoxic compounds. The phytochemical composition reported here can partially justify the traditional uses of C. oppositifolia in Nepal, especially in the treatment of inflammatory diseases, although further research will be needed to assess the full potential of this species.

7-Acetoxycoumarin Inhibits LPS-Induced Inflammatory Cytokine Synthesis by IκBα Degradation and MAPK Activation in Macrophage Cells

Acetylation involves the chemical introduction of an acetyl group in place of an active hydrogen group into a compound. In this study, we synthesized 7-acetoxycoumarin (7AC) from acetylation of umbelliferone (UMB). We examined the anti-inflammatory properties of 7AC in lipopolysaccharide (LPS)-treated RAW 264.7 macrophage cells. The anti-inflammatory activity of 7AC on viability of treated cells was assessed by measuring the level of expression of NO, PGE₂ and pro-inflammatory cytokines, namely interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in 7AC-treated RAW 264.7 macrophages. The 7AC was nontoxic to cells and inhibited the production of cytokines in a concentration-dependent manner. In addition, its treatment suppressed the production of pro-inflammatory cytokines in a dose-dependent manner and concomitantly decreased the protein and mRNA expressions of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2). Moreover, the levels of the phosphorylation of mitogen-activated protein kinase (MAPK) family proteins such as extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38 and nuclear factor kappa B (NF-κB) were reduced by 7AC. In conclusion, we generated an anti-inflammatory compound through acetylation and demonstrated its efficacy in cell-based in vitro assays.

Antioxidant Activity of Encapsulated Extracts and Bioactives from Natural Sources

The low water solubility and low bioavailability of natural bioactive substances such as polyphenols and flavonoids, either in pure form or extracts, are a major concern in the pharmaceutical field and even on the food development sector. Although encapsulation has demonstrated success in addressing these drawbacks, it is important to evaluate the antioxidant activity of the encapsulated compounds. This article reviews the encapsulation of bioactive compounds from natural sources focusing their antioxidant activity after encapsulation. Attention is given to the methods and wall materials used, and the antioxidant activity methodologies (classical in vitro techniques such as DPPH, ORAC, FRAP and others, as well as in vivo/ex vivo tests to evaluate endogenous antioxidant enzymes or oxidative stress) applied to assess the antioxidant capacity are also comprehensively summarized.

Coumarins as Modulators of the Keap1/Nrf2/ARE Signaling Pathway

The Keap1/Nrf2/ARE system is a central defensive mechanism against oxidative stress which plays a key role in the pathogenesis and progression of many diseases. Nrf2 is a redox-sensitive transcription factor controlling a variety of downstream antioxidant and cytodefensive genes. Nrf2 has a powerful anti-inflammatory activity mediated via modulating NF-κB. Therefore, pharmacological activation of Nrf2 is a promising therapeutic strategy for the treatment/prevention of several diseases that are underlined by both oxidative stress and inflammation. Coumarins are natural products with promising pharmacological activities, including antioxidant, anticancer, antimicrobial, and anti-inflammatory efficacies. Coumarins are found in many plants, fungi, and bacteria and have been widely used as complementary and alternative medicines. Some coumarins have shown an ability to activate Nrf2 signaling in different cells and animal models. The present review compiles the research findings of seventeen coumarin derivatives of plant origin (imperatorin, visnagin, urolithin B, urolithin A, scopoletin, esculin, esculetin, umbelliferone, fraxetin, fraxin, daphnetin, anomalin, wedelolactone, glycycoumarin, osthole, hydrangenol, and isoimperatorin) as antioxidant and anti-inflammatory agents, emphasizing the role of Nrf2 activation in their pharmacological activities. Additionally, molecular docking simulations were utilized to investigate the potential binding mode of these coumarins with Keap1 as a strategy to disrupt Keap1/Nrf2 protein-protein interaction and activate Nrf2 signaling.

Synthesis and in vitro and in vivo anti-inflammatory activity of novel 4-ferrocenylchroman-2-one derivatives

A series of novel 4-ferrocenylchroman-2-one derivatives were designed and synthesised to discover potent anti-inflammatory agents for treatment of arthritis. All the target compounds had been screened for their anti-inflammatory activity by evaluating the inhibition effect of LPS-induced NO production in RAW 264.7 macrophages. Among them, 4-ferrocenyl-3,4-dihydro-2H-benzo[g]chromen-2-one (3h) was found to be the most potent compound in inhibiting the productions of NO with low toxicity. This compound also exhibited significant inhibition of the productions of IL-6 and TNF-α in RAW 264.7 macrophages. Preliminary mechanism studies indicated that compound 3h could inhibit the activation of LPS-induced NF-κB and MAPKs signalling pathways. The in vivo anti-inflammatory effect of this compound was determined in the rat adjuvant-induced arthritis model.