Inducible Cyclooxygenase-2 Research Articles

Aspirin and celecoxib revealed anticancer and immunomodulatory effects on colon cancer cells

Colorectal cancer is one of the most common malignancies in the world. Clinical evidence suggests that non-steroidal anti-inflammatory drugs (NSAIDs ) were found to reduce the risk of colonic adenoma and colorectal cancer occurrence or recurrence and are more beneficial in acute inflammatory disorders than in chronic inflammatory diseases, implying that NSAIDs target the early stages of the inflammatory response. Celecoxib inhibits tumor initiation and tumor cell proliferation. Aspirin inhibits the constitutive isoform of the platelet enzyme cyclooxygenase- 1 (COX-1) and the inducible isoform cyclooxygenase-2 (COX-2) which is expressed by cytokines, and some growth factors. In this study, different concentrations of both Celecoxib and Aspirin in various sets were applied to investigate their effects on colon cancer cells (SW480) proliferation and cytokines production. Our result reported a significant decrease in cells viability after the treatment with aspirin and celecoxib alone or in combination. Celecoxib significantly decreased IL-6 levels, while Aspirin treatment showed no significant change in IL-6, IL-12, and TNF- α levels. In conclusion, non-steroidal anti-inflammatory drugs (NSAIDs) have pronounced anti-proliferative effects on colorectal cancer cell lines.

Green tea catechins inhibit Porphyromonas gulae LPS-induced inflammatory responses in human gingival epithelial cells

ObjectivesTo determine the anti-inflammatory effects of green tea catechins in immortalized human gingival epithelial cells (Ca9-22) stimulated with Porphyromonas gulae lipopolysaccharide (LPS). MethodsCa9-22 cells were incubated with P. gulae LPS (10 μg/ml) with or without green tea catechins, epigallocatechin-3-gallate (EGCg), epigallocatechin (EGC), epicatechin-3-gallate (ECG), and epicatechin (EC) (each at 50 μM), for 6 or 24 h. Real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay were used to determine the induction of cyclooxygenase 2 (COX2), tumor necrosis factor alpha (TNF-ɑ), interleukin 6 (IL-6), and IL-8. Furthermore, the expression of toll-like receptors (TLRs) 2 and 4 was examined using real-time PCR and western blotting analysis, and phosphorylation of the p38 and ERK1/2 was examined using western blotting analysis. ResultsAt the mRNA and protein levels, EGCg, EGC, ECG, and EC were found to significantly inhibit COX2, TNF-ɑ, IL-6, and IL-8. Furthermore, the levels of ERK1/2 and p38 phosphorylation induced by P. gulae LPS were decreased following the addition of each of the catechins, as well as TLR2 and 4 mRNA and protein. ConclusionsThese findings indicate that green tea catechins are potent inhibitors of inflammatory responses induced by P. gulae LPS, and may also be useful for prevention and/or attenuation of periodontitis.

THROMBOXANE-DEPENDENT CORONARY VASOCONSTRICTION IN OBESE MICE: ROLE OF PEROXYNITRITE

Objective: Obesity leads to chronic oxidative stress promoting the development of cardiovascular diseases including endothelial dysfunction, which might occur through the cyclooxygenase (COX) pathway. This study aimed to investigate the role of peroxynitrite in the generation of COX-derived products and its role in coronary vascular responses. Design and method: We evaluated arachidonic acid (AA)-dependent coronary vascular responses in isolated hearts from control and obese C57BL/6 mice and explored COX metabolism using the COX-2 inhibitor indomethacin and 1-benzylimidazole, inhibitor of thromboxane synthase (TXS). COX, TXS, and TXA2 receptor (TP) protein expression was assessed in heart homogenates. The release of TXA2 in the coronary circulation was also evaluated. In addition, the possible involvement of peroxynitrite on increased coronary response was explored by detecting peroxynitrite by coumarin boronic acid (CBA) and 3-nitrotyrosine protein expression. Alterations in TXS, and TP receptor protein expression were also evaluated in heart homogenates from obese mice treated with the peroxynitrite scavenger FeTMPyP. Results: Arachidonic acid (AA) dependent coronary vasoconstriction in isolated hearts, increased from 31.06 ± 2.67 mmHg in control mice to 88.99 ± 6.09 mmHg in obese mice. Both, indomethacin and 1-benzylimidazole reduced the vasoconstriction response in control and obese mice. TXA2 released during AA-induced vasoconstriction phase was increased in heart perfusates from 76.1 ± 18.42 pg/mL in control mice to 203.6 ± 29.8 pg/mL in obese mice. COX- 2, TXS and TP receptor protein expression was increased in hearts from obese mice (1.96 ± 0.25, 0.70 ± 0.07, 1.22 ± 0.19 arbitrary units, respectively) compared with control mice (0.17 ± 0.02; 0.06 ± 0.02; and 0.29 ± 0.06 arbitrary units, respectively). Moreover, nitrotyrosine and peroxynitrite levels were higher in obese mice, compared with control mice. Increase in coronary vasoconstriction, TXA2 release as well as protein expression was prevented with FeTMPyP treatment in obese mice. Conclusions: Peroxynitrite-dependent induction of COX-2 and TXS protein expression in heart tissue from obese mice may lead to increased TXA2 coronary circulation, thereby increasing coronary vasoconstriction.

Blood Clots versus PRF: Activating TGF-β Signaling and Inhibiting Inflammation In Vitro.

The preparation of platelet-rich fibrin (PRF) requires blood centrifugation to separate the yellow plasma from the red erythrocyte fraction. PRF membranes prepared from coagulated yellow plasma are then transferred to the defect sites to support tissue regeneration. During natural wound healing, however, it is the unfractionated blood clot (UBC) that fills the defect site. It is unclear whether centrifugation is necessary to prepare a blood-derived matrix that supports tissue regeneration. The aim of the present study was to compare lysates prepared from PRF and UBC based on bioassays and degradation of the respective membranes. We report here that lysates prepared from PRF and UBC membranes similarly activate TGF-β signaling, as indicated by the expression of interleukin 11 (IL-11), NADPH oxidase 4 (NOX-4) and proteoglycan 4 (PRG4) in gingival fibroblasts. Consistently, PRF and UBC lysates stimulated the phosphorylation and nuclear translocation of Smad3 in gingival fibroblasts. We further observed that PRF and UBC lysates have comparable anti-inflammatory activity, as shown by the reduction in lipopolysaccharide (LPS)-induced IL-6, inducible nitric oxidase synthase (iNOS) and cyclooxygenase 2 (COX-2) expression in RAW264.7 cells. Moreover, inflammation induced by Poly (1:C) HMW and FSL-1, which are agonists of Toll-like receptor (TLR) 3 and 2/6, respectively, was reduced by both PRF and UBC. PRF and UBC lysates reduced the nuclear translocation of p65 in LPS-induced RAW264.7 cells. In contrast to the similar activity observed in the bioassays, UBC membranes lack the structural integrity of PRF membranes, as indicated by the rapid and spontaneous disintegration of UBC membranes. We show here that the lysates prepared from PRF and UBC possess robust TGF-β and anti-inflammatory activity. However, visual inspection of the PRF and UBC membranes confirmed the negative impact of erythrocytes on the structural integrity of membranes prepared from whole blood. The data from the present study suggest that although both UBC and PRF have potent TGF-β and anti-inflammatory activity, UBC does not have the strength properties required to be used clinically to prepare applicable membranes. Thus, centrifugation is necessary to generate durable and clinically applicable blood-derived membranes.

Anti-Inflammatory Lignans from the Roots of Asarum heterotropoides var. mandshuricum and Their Mechanism of Action.

Bioassay-guided fractionation of Asarum heterotropoides var. mandshuricum F. Maekawa (Aristolochiaceae) root extract led to the isolation and characterization of one new ferulic acid glucose ester (1) and nine known lignans (2-10). Their structures were elucidated using extensive spectroscopic methods, including 1D and 2D NMR, and MS spectra. The anti-inflammatory effects of the isolated compounds were investigated via their inhibition against nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 mouse macrophage cells. Among them, compound 7 ((1R,2S,5R,6R)-5'-O-methylpluviatilol) showed the most effective inhibitory activity against NO production and expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein in an exceedingly dose-dependent manner. In addition, further study revealed that the mechanism of anti-inflammatory activity of the most active lignan (7) might be associated with the inhibition of extracellular-signal-regulated kinase (ERK) and nuclear factor kappa B (NF-κB) phosphorylation.

Anti-Inflammatory Mechanism of An Alkaloid Rutaecarpine in LTA-Stimulated RAW 264.7 Cells: Pivotal Role on NF-κB and ERK/p38 Signaling Molecules.

Lipoteichoic acid (LTA) is a key cell wall component and virulence factor of Gram-positive bacteria. LTA contributes a major role in infection and it mediates inflammatory responses in the host. Rutaecarpine, an indolopyridoquinazolinone alkaloid isolated from Evodia rutaecarpa, has shown a variety of fascinating biological properties such as anti-thrombotic, anticancer, anti-obesity and thermoregulatory, vasorelaxing activity. It has also potent effects on the cardiovascular and endocrine systems. Herein, we investigated rutaecarpine’s (Rut) anti-inflammatory effects in LTA-stimulated RAW macrophage cells. The Western blot and spectrophotometric results revealed that Rut inhibited the production of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and interleukin (IL)-1β in the LTA-induced macrophage cells. Successively, our mechanistic studies publicized that Rut inhibited LTA-induced phosphorylation of mitogen-activated protein kinase (MAPK) including the extracellular signal-regulated kinase (ERK), and p38, but not c-Jun NH2-terminal kinase (JNK). In addition, the respective Western blot and confocal image analyses exhibited that Rut reserved nuclear transcription factor kappa-B (NF-κB) by hindering inhibitor of nuclear factor κB-α (IκBα) and NF-κB p65 phosphorylation and p65 nuclear translocation. These results indicate that Rut exhibits its anti-inflammatory effects mainly through attenuating NF-κB and ERK/p38 signaling pathways. Overall, this result suggests that Rut could be a potential therapeutic agent for the treatment of Gram-positive bacteria induced inflammatory diseases.

Amelioration of TPA-induced skin inflammation by the leaf extract of Vernonia amygdalina involves ERK/STAT3 (Ser727) signaling inhibition

BackgroundUncontrolled inflammation causes health problems. Extracellular signal-regulated kinase (ERK) phosphorylates signal transducer and activator of transcription 3 (STAT3) at Ser727, resulting in inflammation. The leaf of Vernonia amygdalina (VA) is a medicinal herb for managing inflammation-associated diseases. Oral administration or topical application of VA leaf extract exerts anti-inflammatory effects in rat models. However, the anti-inflammatory mechanisms of the herb are not fully understood. PurposeIn this study, we aimed to investigate the involvement of ERK/STAT3 (Ser727) signaling in the anti-inflammatory effects of an ethanolic extract of VA leaves. Study design and methodsExtracts of VA leaves were prepared with different concentrations of ethanol. A LPS-stimulated RAW264.7 cell model was used for in vitro assays, and a TPA (12-O-tetradecanoylphorbol-13-acetate)-induced ear edema mouse model was employed for in vivo assays. The 95% ethanol extract of VA leaves (VAE) exerted the strongest inhibitory effect on nitric oxide (NO) production in LPS-stimulated macrophages; thus it was selected for use in this study. Hematoxylin and eosin (H&E) staining was used to examine pathological conditions of mouse ear tissues. Griess reagent was employed to examine NO generation in cell cultures. Immunoblotting and ELISA were used to examine protein levels, and RT-qPCR was employed to examine mRNA levels. ResultsTopical application of VAE ameliorated mouse ear edema induced by TPA. VAE suppressed the phosphorylation of ERK (Thr202/Tyr204) and STAT3 (Ser727); and decreased protein levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin (IL)-6, IL-1β and tumor necrosis factor-α (TNF-α) in the mouse ear tissues and in LPS-stimulated RAW 264.7 cells. VAE also inhibited NO production, and lowered mRNA levels of IL-6, IL-1β and TNF-α in the macrophages. ConclusionsVAE ameliorates TPA-induced mouse ear edema. Suppression of ERK/STAT3 (Ser727) signaling is involved in VAE's anti-inflammatory effects. These novel data provide further pharmacological justifications for the medicinal use of VA in treating inflammation-associated diseases, and lay the groundwork for developing VAE into a new anti-inflammatory agent.

Anti-Inflammatory Effects of Psoralen Derivatives on RAW264.7 Cells via Regulation of the NF-κB and MAPK Signaling Pathways.

Using repositioning to find new indications for existing functional substances has become a global target of research. The objective of this study is to investigate the anti-inflammatory potential of psoralen derivatives (5-hydroxypsoralen, 5-methoxypsoralen, 8-hydroxypsoralen, and 8-methoxypsoralen) in macrophages cells. The results indicated that most psoralen derivatives exhibited significantly inhibited prostaglandin E2 (PGE2) production, particularly for 8-hydroxypsoralen (xanthotoxol) in lipopolysaccharide (LPS)-stimulated macrophage RAW 264.7 cells. In addition, xanthotoxol treatment decreased the PGE2, IL-6, and IL-1β production caused by LPS stimulation in a concentration-dependent manner. Moreover, Western blot results showed that the protein levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), which activated with LPS treatment, were decreased by xanthotoxol treatment. Mechanistic studies revealed that xanthotoxol also suppressed LPS-stimulated phosphorylation of the inhibitor of κBα (IκBα), p38 mitogen-activated protein kinase (MAPK), and c-Jun N-terminal kinase (JNK) in RAW 264.7 cells. The Western blot assay results show that xanthotoxol suppresses LPS-induced p65 translocation from cytosol to the nucleus in RAW 264.7 cells. Moreover, we tested the potential application of xanthotoxol as a cosmetic material by performing human skin patch tests. In these tests, xanthotoxol did not induce any adverse reactions at a 100 μΜ concentration. These results demonstrate that xanthotoxol is a potential therapeutic agent for topical application that inhibits inflammation via the MAPK and NF-κB pathways.

The licorice flavonoid isoliquiritigenin attenuates Mycobacterium tuberculosis-induced inflammation through Notch1/NF-κB and MAPK signaling pathways

Ethnopharmacological relevanceThe genus Glycyrrhiza is a small perennial herb that has been traditionally used to treat many diseases across the world. Licorice (Gancao in Chinese) is the dried root and rhizome of G. glabra, G. uralensis or G. inflata. Licorice plays an important role in traditional Chinese medicine (TCM), and is the most frequently used in Chinese herbal formulas. Isoliquiritigenin (ISL) is a flavonoid extracted from licorice, and has been evaluated for its various biological activities, including anti-inflammatory, anti-tumor and anti-oxidant activities. Excessive and persistent inflammation in the Mycobacterium tuberculosis (Mtb) infection is not conducive to the elimination of Mtb, but contributes to serious pulmonary dysfunction. Aim of the studyThis study aimed to examine the anti-inflammatory effects of ISL in the Mtb infection. MethodsIn vitro models of Mtb-infected macrophages were established. Murine macrophage Raw 264.7 cells and primary peritoneal macrophages were used in this study. Cell viability was determined by the cell counting kit-8 (CCK-8) assay. The effects of ISL on the secretion levels of interleukin -1β (IL-1β), tumor necrosis factor -α (TNF-α), and interleukin −6 (IL-6) were detected by the enzyme-linked immunosorbent assay (ELISA). The expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2) were measured by the real time quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blot. Western blot was used to assess the effects of ISL on the activation of NLRP3 inflammasome and Notch1/NF-κB and MAPK signaling pathways. Immunofluorescence assays was used to detected the translocation of phosphorylation of p65 subunit of NF-κB. ResultsIt was revealed that ISL inhibited the secretion of IL-1β and the activation of pore-forming protein (gasdermin D, GSDMD) by suppressing the activation of NLPR3 inflammasome induced by Mtb infection. ISL was also shown to have promising inhibitory effects on inflammatory factors, such as TNF-α, IL-6, iNOS and COX2. Regarding the anti-inflammatory mechanism of ISL, it was found that ISL exerted its anti-inflammatory effects by inhibiting the activation of Notch1/NF-κB and MAPK signaling pathways. ConclusionISL reduced Mtb-induced inflammation through the Notch1/NF-κB and MAPK signaling pathways. ISL might be used as a potential adjuvant drug to treat tuberculosis by adjusting host immune responses.

Levilactobacillus brevis KU15151 Inhibits Staphylococcus aureus Lipoteichoic Acid-Induced Inflammation in RAW 264.7 Macrophages.

Inflammation is a host defense response to harmful agents, such as pathogenic invasion, and is necessary for health. Excessive inflammation may result in the development of inflammatory disorders. Levilactobacillusbrevis KU15151 has been reported to exhibit probiotic characteristics and antioxidant activities, but the effect of this strain on inflammatory responses has not been determined. The present study aimed to investigate the anti-inflammatory potential of L. brevis KU15151 in Staphylococcus aureus lipoteichoic acid (aLTA)-induced RAW264.7 macrophages. Treatment with L. brevis KU15151 reduced the production of nitric oxide and prostaglandin E2 by suppressing the expression of inducible nitric oxide synthase and cyclooxygenase-2. Additionally, the production of proinflammatory cytokines including tumor necrosis factor-α, interleukin (IL)-6, and IL-1β, decreased after treatment with L. brevis KU15151 in aLTA-stimulated RAW 264.7 cells. Furthermore, this strain alleviated the activation of nuclear factor-κB and mitogen-activated protein kinase signaling pathways. Moreover, the generation of reactive oxygen species was downregulated by treatment with L. brevis KU15151. These results demonstrate that L. brevis KU15151 possesses an inhibitory effect against aLTA-mediated inflammation and may be employed as a functional probiotic for preventing inflammatory disorders.

Antitumor Activity of Zinc Nanoparticles Synthesized with Berberine on Human Epithelial Colorectal Adenocarcinoma (Caco-2) Cells through Acting on Cox-2/NF-kB and p53 Pathways.

Drawbacks and side effects of currently available therapies to colorectal cancer (CRC) have compelled researchers to search for new therapeutic strategies. This study was designed to investigate the effects of zinc nanoparticles biosynthesized with berberine (ZnNPs-BER) on Caco-2 cells compared to 5-Fluorouracil (5-FU) and explore the possible underlying pathways. Caco-2 and Vero cells were treated with 5-FU, BER, or ZnNPs-BER for 24 h. Cell viability was measured by MTT assay. Oxidative stress and apoptotic markers and cell cycle were determined. Additionally, Cox-2 and NF-kB levels were also measured. The IC50 values of 5-FU, BER, and ZnNPs-BER on Caco-2 cells were found to be 34.65 μM, 19.86 μg/ml and 10.49 μg/ml, respectively by MTT assay. The IC50 value for 5-FU in Vero cells was 21.7 μg/ml, however, BER and BER-ZnNPs treatment showed non-toxic effects on the Vero cells. Further, ZnNPs-BER exerted significant induction of ROS besides exhaustion of the antioxidant capacity of tumor cells indicated by a decline in GSH and elevated NO and MDA contents. Marked increments in levels of Bax and caspase-3 were detected together with declines in Bcl- 2 levels in Caco-2 cells subjected to BER-ZnNPs therapy. On the molecular basis, upregulation in mRNA levels of pro-apoptotic genes (Bax, caspase-3, and tumor suppressor gene p53) along with downregulation in the anti-apoptotic gene (Bcl-2) were observed in ZnNPs-BER treated Caco-2 cells. Furthermore, ZnNPs-BER showed more pronounced effects on apoptosis increased cell percentage in the S and subG1 phases. In addition, green synthesis of ZnNPs with BER showed notable induction of Cox2 and NF-kB in Caco-2 cells. Therefore, the antitumor potential of ZnNPs-BER in colon cancer cells may be endorsed for induction of oxidative stress, inflammation, and apoptotic changes in tumor cells. Our study documents the therapeutic potential of Zn nanoparticles conjugated with BER, which may be a new option for combined chemotherapy.

MO614: Modified Lipid Metabolism and Cytosolic Phospholipase A2 Activation in Mesangial Cells Under Pro-Inflammatory Conditions

Abstract BACKGROUND AND AIMS Diabetic kidney disease (DKD) is thought to be a consequence of hyperglycemia and driven by early glomerular hemodynamic changes and progressive expansion of the mesangium. The molecular mechanism behind the pathophysiological alterations of the mesangium is yet to be elucidated. This study aimed at investigating whether lipid signaling might be the missing link. METHOD Human mesangial cells (HMCs) were stimulated with high glucose, IL-1β or PDGF-BB. Production of IL-1β and PDGF-BB, COX-2 induction and cPLA2 activation and prostaglandin secretion were investigated using a combination of ELISA, western blot, lipidomics, qPCR and activity assays. Inhibition of cPLA2 was evaluated using ELISA, migration and proliferation assays. Validation of data was performed in silico using the Nephroseq database [1] and a recently published glomerular transcriptomic DKD database. [2] RESULTS Stimulation of HMCs with high glucose primed IL-1β secretion through inflammasome NLRP3 signaling. In turn, IL-1β was able to stimulate PDGF-BB release. PDGF-BB increased IL-1β secretion synergistically. Both IL-1β and PDGF-BB stimuli caused lipid metabolism variations and in particular triggered the formation of phosphorylated sphingoid bases (PSBs) and the activation of the enzymes cPLA2 and COX-2. This led to the formation of prostanoids from arachidonic acid produced by cPLA2. As a result, prostaglandins were secreted. Another product of cPLA2 activation was lysophosphatidic acid (LPA), a proliferation effector. Blocking cPLA2-mediated release of arachidonic acid could in fact reduce HMCs’ proliferation and secretion of prostaglandins. CONCLUSION Hyperglycemia primes glomerular inflammatory and proliferative stimuli triggering lipid metabolism modifications in HMCs. The upregulation of cPLA2 was found to be critical in this setting. cPLA2 inhibition with AACOCF3 reduced mesangial secretion of prostaglandins and proliferation, making it a potential target for DKD therapy.

Flavonoids as Potential Anti-Inflammatory Molecules: A Review.

Hydroxylated polyphenols, also called flavonoids, are richly present in vegetables, fruits, cereals, nuts, herbs, seeds, stems, and flowers of numerous plants. They possess numerous medicinal properties such as antioxidant, anti-cancer, anti-microbial, neuroprotective, and anti-inflammation. Studies show that flavonoids activate antioxidant pathways that render an anti-inflammatory effect. They inhibit the secretions of enzymes such as lysozymes and β-glucuronidase and inhibit the secretion of arachidonic acid, which reduces inflammatory reactions. Flavonoids such as quercetin, genistein, apigenin, kaempferol, and epigallocatechin 3-gallate modulate the expression and activation of a cytokine such as interleukin-1beta (IL-1β), Tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-8 (IL-8); regulate the gene expression of many pro-inflammatory molecules such s nuclear factor kappa-light chain enhancer of activated B cells (NF-κB), activator protein-1 (AP-1), intercellular adhesion molecule-1 (ICAM), vascular cell adhesion molecule-1 (VCAM), and E-selectins; and also inhibits inducible nitric oxide (NO) synthase, cyclooxygenase-2, and lipoxygenase, which are pro-inflammatory enzymes. Understanding the anti-inflammatory action of flavonoids provides better treatment options, including coronavirus disease 2019 (COVID-19)-induced inflammation, inflammatory bowel disease, obstructive pulmonary disorder, arthritis, Alzheimer’s disease, cardiovascular disease, atherosclerosis, and cancer. This review highlights the sources, biochemical activities, and role of flavonoids in enhancing human health.

Revolutionizing non-conventional wound healing using honey by simultaneously targeting multiple molecular mechanisms.

Hospital-acquired infections and treatment-related wound complications constitute a tremendous burden for the health care system, particularly given the serious increase in multidrug resistant pathogens. Imagine that a large part of nosocomial infections can be prevented using a simple treatment. In this respect, honey is used mainly in topical cutaneous wound care because of its potent broad-spectrum antibacterial and wound healing activities. However, therapeutic use outside this scope has been limited. The current review provides an in-depth view of studies using honey outside the conventional wound care indications. Non-conventional routes of honey application include subcutaneous, intra-socket, abdominal, and oral administration in novel indications, such as post colon surgery, mucositis, and tooth extraction. Honey consistently demonstrates beneficial therapeutic activities in these novel applications, orchestrating antimicrobial and prophylactic activity, reducing inflammation and wound dehiscence, and inducing healing, epithelialization, and analgesic activity. Several molecular mechanisms are responsible for these beneficial clinical effects of honey during the course of wound healing. Pro-inflammatory effects of honey, such as induction of iNOS, IL-1β, and COX-2, are mediated by TLR4 signaling. In contrast, honey's anti-inflammatory actions and flavonoids induce anti-inflammatory and antioxidant pathways by inducing NRF2 target genes, including HO-1 and PRDX1. The molecular and biochemical pathways activated by honey during the different phases of wound healing are also discussed in more detail in this review. Variation between different honey origins exists, and therefore standardized medical-grade honey may offer an optimized and safe treatment. Honey is a valuable alternative to conventional antimicrobial and anti-inflammatory therapies that can strongly reduce nosocomial infections.

The neuroprotective effect of a novel 1,4‐Dihydroquinazolin‐3(2H)‐yl benzamide derivative against chronic constriction injury‐induced neuropathic pain in rats

BackgroundNeuropathic pain (NP) is a severe, chronic inflammatory condition affecting both the central and peripheral nervous systems and is resistant to standard treatment. Nonsteroidal anti‐inflammatory drugs (NSAIDs) are commonly used to treat NP, but they are not the best option due to their limited penetration of the blood‐brain barrier and the gastrointestinal side effects associated with long‐term use. We recently reported a new series of benzamide derivatives that inhibit cyclooxygenase 2 (COX2) with comparable selectivity to celecoxib and tolerable side effects. Among these derivatives, 4‐chloro‐N‐(2‐(4‐chlorophenyl)‐1‐methyl‐4‐oxo‐1,4‐dihydroquinazolin‐3(2H)‐yl)benzamide (4b) demonstrated potent anti‐inflammatory and analgesic properties, as well as 32‐fold greater CNS accessibility than celecoxib. We aim to investigate the anti‐inflammatory and anti‐nociceptive effects of 4b against NP utilizing chronic constriction injury (CCI) model of neuropathy, elucidating the molecular mechanisms involved in its effect on both the peripheral (sciatic nerve) and central (brainstem) levels.MethodsThe CCI was performed unilaterally in male Wistar rats (275–300 g, n=5/group) given 4b (5 and 10 mg/kg, p.o), the standard drug for NP pregabalin (30 mg/kg, p.o), or vehicle for 14 days. Pain‐related behaviors, including mechanical and thermal hyperalgesia, were performed prior to and on days 7 and 14 post‐surgery. Sciatic nerve and brainstem oxidative stress [NADPH oxidase2 (NOX2) and catalase] and inflammatory [inducible nitric oxide synthase (iNOS), prostaglandin E2 (PGE2), COX2, and 5‐lipoxygenase] markers were detected by ELISA. Myelin sheath integrity was assessed in paraformaldehyde‐fixed sciatic nerve sections (4μm) stained with osmic acid, and the ratios of myelinated to total nerve area were calculated using ImageJ software.Immunohistochemistry was used to detect the expression of the microglial marker CD68 and the astrocyte marker GFAP as indicators of glial cell activation in the brainstem.ResultsCCI rats had increased mechanical and thermal hypersensitivity, which peaked 14 days post‐surgery. Compared to sham‐operated controls, CCI‐rats had significantly higher levels of sciatic nerve and brainstem inflammatory (3‐8‐fold, p<0.05) and oxidative stress (7‐10‐fold higher NOX2) markers, but lower catalase levels (sciatic nerve: 26.60 ± 4.15 vs. 203.08 ± 16.4 mU/mg protein, and brainstem: 25.90 ± 2.56 vs. 216.40 ± 7.50 mU/mg protein). 4b mitigated pain behaviors, indicating a strong central analgesic effect. Furthermore, all biochemical measurements were dose‐dependently attenuated in the 4b‐treated groups. CCI‐induced increases in microglial cell infiltration (CD68 expression) and astrocyte activation (GFAP expression) were attenuated in 4b‐treated CCI‐rats. Osmic acid stain of the sciatic nerve revealed that 4b administration restored the normal nerve architecture and integrity that had been lost due to CCI. Excitingly, 4b (10 mg/kg) was superior to pregabalin in terms of behavioral, biochemical, and structural effects.Conclusion and significanceOur data show that the novel compound tested has potent peripheral and central analgesic and anti‐inflammatory properties, highlighting the potential of its use as a promising therapeutic approach for treating NP.

PPARα agonist WY-14,643 induces the PLA2/COX-2/ACOX1 pathway to enhance peroxisomal lipid metabolism and ameliorate alcoholic fatty liver in mice

Peroxisome proliferator-activated receptor α (PPARα) regulates fatty acid oxidation (FAO). Usually, very-long chain fatty acids are first activated by acyl-CoA synthetase (ACS) to generate acyl-CoA for oxidation by acyl-CoA oxidase (ACOX) in peroxisomes, and the resultant shorter chain fatty acids will be further oxidized in mitochondria. ACS long-chain family member 4 (ACSL4) preferentially uses arachidonic acid (AA) as substrates to synthesize arachidonoyl-CoA. Arachidonoyl-CoA is usually esterified into phospholipids. When AA is released by phospholipase A2 (PLA2) from phospholipids, it will be used for prostaglandin synthesis by cyclooxygenases (COX). In this study, when PPARα agonist WY-14,643 was mixed in liquid Lieber-DeCarli ethanol or control diets and fed to mice, liver PLA2, COX-2, and ACOX1 were induced but ACSL4 was inhibited, suggesting that AA released by PLA2 from phospholipid will be metabolized to prostaglandin via COX-2 instead of being synthesized into acyl-CoA by ACSL4. However, liver prostaglandin E2 (PGE2), a major component of prostaglandin, was not increased with the induced COX-2 but decreased by WY-14,643. ACOX1 specific inhibitor mixed in the liquid diets restored both the WY-14,643-suppressed liver TG and PGE2, but COX-2 specific inhibitor celecoxib mixed in the liquid diets reversed the WY-14,643-suppressed liver TG but not liver PGE2 contents. These results suggest that induction of PLA2, COX-2 and ACOX1 orchestrates to increase oxidation of AA/PGE2, which constitutes one new mechanism by which PPARα induces peroxisomal FAO and inhibits ethanol-induced liver fat accumulation.

Mulberry vinegar attenuates lipopolysaccharide and interferon gamma-induced inflammatory responses in C6 glial cells.

The present study evaluated the effect of mulberry vinegar (MV) on the regulation of the inflammatory responses using C6 glial cells. Treatment with lipopolysaccharide (LPS) and interferon-γ (IFN-γ) induced the nitric oxide and reactive oxygen species generation, while pre-incubation with MV inhibited these formations in a concentration-dependent manner. MV treatment also decreased the production of pro-inflammatory cytokines, such as interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α in C6 glial cells stimulated by LPS/IFN-γ. Compared to the LPS/IFN-γ-treated control group, the MV-treated group exerts downregulation in the protein expressions of inducible nitric oxide synthase and cyclooxygenase-2, through inhibition of nuclear factor-κB activation. Protein expressions of glial fibrillary acidic protein and ionized calcium-binding adapter molecule 1 were also decreased in the MV-treated group. These findings suggest that MV prevents neuroinflammation by regulating the NF-κB signaling pathway and glial activation. PRACTICAL APPLICATION: Mulberry fruits (Morus alba L.) have been commonly consumed as juice or jam. It is a rich source of anthocyanins that might be associated with beneficial effects on human health, including the anti-oxidant, anti-inflammatory, anti-obesity, and anti-diabetic effects. Mulberry vinegar was produced by alcohol and acetic fermentation of mulberry juice, and they possessed a protective effect against LPS/IFN-γ-stimulated inflammatory responses in glial cells via regulation of glial activation and NF-κB signaling pathway (i.e., downregulation of iNOS, COX-2, TLR4, p-IκB, and NF-κB p65 protein expressions). Although further research especially animal and clinical trials are still necessary, the present study will be helpful to scale-up the production of functional vinegar with neuroprotective and anti-inflammatory properties using mulberry.

Mosloflavone-Resveratrol Hybrid TMS-HDMF-5z Exhibits Potent In Vitro and In Vivo Anti-Inflammatory Effects Through NF-κB, AP-1, and JAK/STAT Inactivation.

TMS-HDMF-5z is a hybrid of the natural products mosloflavone and resveratrol. It was discovered to show potent inhibitory effects against lipopolysaccharide (LPS)-induced production of inflammatory mediators in RAW 264.7 macrophages. However, its mechanism of action is unknown. Hence this study aimed to demonstrate and explore in vitro and in vivo anti-inflammatory effects of TMS-HDMF-5z and its mechanism of action employing RAW 264.7 macrophages and carrageenan-induced hind paw edema. This work revealed that TMS-HDMF-5z suppressed the LPS-induced inducible nitric-oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the protein, mRNA, and promoter binding levels and tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6, and interferon-β (IFN-β) at the mRNA expression in RAW 264.7 macrophages. The results showed that TMS-HDMF-5z reduced the transcription and DNA binding activities of nuclear factor-κB (NF-κB) through inhibiting nuclear translocation of p65 and phosphorylation of κB inhibitor α (IκBα), IκB kinase (IKK), and TGF-β activated kinase 1 (TAK1). Additionally, TMS-HDMF-5z attenuated the LPS-induced transcriptional and DNA binding activities of activator protein-1 (AP-1) by suppressing nuclear translocation of phosphorylated c-Fos, c-Jun, and activating transcription factor 2 (ATF2). TMS-HDMF-5z also reduced the LPS-induced phosphorylation of Janus kinase 1/2 (JAK1/2), signal transducers and activators of transcription 1/3 (STAT1/3), p38 mitogen-activated protein kinase (MAPK), and MAPK-activated protein kinase 2 (MK2). In rats, TMS-HDMF-5z alleviated carrageenan-induced hind paw edema through the suppressing iNOS and COX-2 via NF-κB, AP-1, and STAT1/3 inactivation. Collectively, the TMS-HDMF-5z-mediated inhibition of NF-κB, AP-1, and STAT1/3 offer an opportunity for the development of a potential treatment for inflammatory diseases.

Thrombin Induces COX-2 and PGE2 Expression via PAR1/PKCalpha/MAPK-Dependent NF-kappaB Activation in Human Tracheal Smooth Muscle Cells.

The inflammation of the airway and lung could be triggered by upregulation cyclooxygenase (COX)-2 and prostaglandin E2 (PGE2) induced by various proinflammatory factors. COX-2 induction by thrombin has been shown to play a vital role in various inflammatory diseases. However, in human tracheal smooth muscle cells (HTSMCs), how thrombin enhanced the levels of COX-2/PGE2 is not completely characterized. Thus, in this study, the levels of COX-2 expression and PGE2 synthesis induced by thrombin were determined by Western blot, promoter-reporter assay, real-time PCR, and ELISA kit. The various signaling components involved in the thrombin-mediated responses were differentiated by transfection with siRNAs and selective pharmacological inhibitors. The role of NF-κB was assessed by a chromatin immunoprecipitation (ChIP) assay, immunofluorescent staining, as well as Western blot. Our results verified that thrombin markedly triggered PGE2 secretion via COX-2 upregulation which were diminished by the inhibitor of thrombin (PPACK), PAR1 (SCH79797), Gi/o protein (GPA2), Gq protein (GPA2A), PKCα (Gö6976), p38 MAPK (SB202190), JNK1/2 (SP600125), MEK1/2 (U0126), or NF-κB (helenalin) and transfection with siRNA of PAR1, Gqα, Giα, PKCα, JNK2, p38, p42, or p65. Moreover, thrombin induced PAR1-dependent PKCα phosphorylation in HTSMCs. We also observed that thrombin induced p38 MAPK, JNK1/2, and p42/p44 MAPK activation through a PAR1/PKCα pathway. Thrombin promoted phosphorylation of NF-κB p65, leading to nuclear translocation and binding to the COX-2 promoter element to enhance promoter activity, which was reduced by Gö6976, SP600125, SB202190, or U0126. These findings supported that COX-2/PGE2 expression triggered by thrombin was engaged in PAR1/Gq or Gi/o/PKCα/MAPK-dependent NF-κB activation in HTSMCs.

Inhibition of the Akt/NF-κB pathway is involved in the anti-gastritis effects of an ethanolic extract of the rhizome of Atractylodes macrocephala

Ethnopharmacological relevanceGastritis can lead to ulcers and the development of gastric cancer. The rhizome of Atractylodes macrocephala Koidz. (Asteraceae), a traditional Chinese medicinal herb, is prescribed for the treatment of gastric disorders, hepatitis and rheumatism. Its bio-active compounds are considered to be particularly effective in this regard. However, the molecular processes of the herb's anti-inflammatory activity remain obscure. This study elucidates a mechanism upon which an ethanolic extract of this herb (Am-EE) exerts anti-inflammation effects in RAW264.7 macrophage cells (RAW cells) stimulated by lipopolysaccharide (LPS) treatment and HCl Ethanol-stimulated gastritis rats. Aim of the studyTo investigate the anti-gastritis activities of Am-EE and explore the mode of action. Materials and methodsEthanol (95%) was used to prepare Am-EE. The quality of the extract was monitored by HPLC analysis. The in vivo effects of this extract were examined in an HCl Ethanol-stimulated gastritis rat model, while LPS-stimulated RAW cells were used for in vitro assays. Cell viability and nitric oxide (NO) production were observed by MTT and Griess assays. Real-time PCR was used to examine mRNA expression. The PGE2 ELISA kit was employed to detect prostaglandin E2 (PGE2). Enzyme activities and protein contents were examined by immunoblotting. Luciferase reporter gene assays (LRA) were employed to observe nuclear transcription factor (NF)-κB activity. The SPSS (SPSS Inc., Chicago, Illinois, United States) application was used for statistical examination. ResultsHPLC analysis indicates that Am-EE contains atractylenolide-1 (AT-1, 1.33%, w/w) and atractylenolide-2 (AT-2, 1.25%, w/w) (Additional Figure. A1). Gastric tissue damage (induced by HCl Ethanol) was significantly decreased in SD rats following intra-gastric application of 35 mg/kg Am-EE. Indistinguishable to the anti-inflammation effects of 35 mg/kg ranitidine (gastric medication). Am-EE treatment also reduced LPS-mediated nitric oxide (NO) and prostaglandin E2 (PGE2) production. The mRNA and protein synthesis of inducible cyclooxygenase (COX)-2 and NO synthase (iNOS) was down-regulated following treatment in RAW cells. Am-EE decreased NF-κB (p50) nuclear protein levels and inhibited NF-κB-stimulated LRA activity in RAW cells. Lastly, Am-EE decreased the up-regulated levels of phosphorylated IκBα and Akt proteins in rat stomach lysates and in LPS challenged RAW cell samples. ConclusionOur study illustrates that Am-EE suppresses the Akt/IκBα/NF-κB pathway and exerts an anti-inflammatory effect. These novel conclusions provide a pharmacological basis for the clinical use of the A. macrocephala rhizome in the treatment and prevention of gastritis and gastric cancer.