Celecoxib exerts protective effects in the vascular endothelium via COX-2-independent activation of AMPK-CREB-Nrf2 signalling

Cyclooxygenase-2 inhibitors alleviated depressive and anxious-like behaviors in mice exposed to lipopolysaccharide: Involvement of oxidative stress and neuroinflammation

Depression and anxiety disorders have their pathophysiologies linked to inflammation and oxidative stress. In this context, celecoxib (CLX) and etoricoxib (ETR) inhibit cyclooxygenase 2 (COX-2), an enzyme expressed by cells involved in the inflammatory process and found in the brain. Studies have been using CLX as a possible drug in the treatment of depression, although its mechanisms at the central nervous system level are not fully elucidated. In this study, the effects of CLX and ETR on behavioral, oxidative, and inflammatory changes induced by systemic exposure to Escherichia coli lipopolysaccharide (LPS) were evaluated in adult male swiss mice. For ten days, the animals received intraperitoneal injections of LPS at 0.5 mg/kg. From the sixth to the tenth day, one hour after LPS exposure, they were treated orally with CLX (15 mg/kg), ETR (10 mg/kg), or fluoxetine (FLU) (20 mg/kg). Twenty-four hours after the last oral administration, the animals underwent evaluation of locomotor activity (open field test), predictive tests for depressive-like behavior (forced swim and tail suspension tests), and anxiolytic-like effect (elevated plus maze and hole board tests). Subsequently, the hippocampus, prefrontal cortex and striatum were dissected for the measurement of oxidative and nitrosative parameters (malondialdehyde, nitrite, and glutathione) and quantification of pro-inflammatory cytokines (IL-1β and IL-6). LPS induced depressive and anxious-like behavior, and treatment with CLX or ETR was able to reverse most of the behavioral changes. It was evidenced that nitrosative stress and the degree of lipid peroxidation induced by LPS were reduced in different brain areas after treatment with the drugs, as well as the endogenous defense system against free radicals was strengthened. CLX and ETR also significantly reduced LPS-induced cytokine levels. These data are expected to expand information on the role of inflammation in depression and anxiety and provide insights into possible mechanisms of COX-2 inhibitors in psychiatric disorders with a neurobiological basis in inflammation and oxidative stress.

Reprimo (RPRM) mediates neuronal ferroptosis via CREB-Nrf2/SCD1 pathways in radiation-induced brain injury

Neuronal ferroptosis has been found to contribute to degenerative brain disorders and traumatic and hemorrhagic brain injury, but whether radiation-induced brain injury (RIBI), a critical deleterious effect of cranial radiation therapy for primary and metastatic brain tumors, involves neuronal ferroptosis remains unclear. We have recently discovered that deletion of reprimo (RPRM), a tumor suppressor gene, ameliorates RIBI, in which its protective effect on neurons is one of the underlying mechanisms. In this study, we found that whole brain irradiation (WBI) induced ferroptosis in mouse brain, manifesting as alterations in mitochondrial morphology, iron accumulation, lipid peroxidation and a dramatic reduction in glutathione peroxidase 4 (GPX4) level. Moreover, the hippocampal ferroptosis induced by ionizing irradiation (IR) mainly happened in neurons. Intriguingly, RPRM deletion protected the brain and primary neurons against IR-induced ferroptosis. Mechanistically, RPRM deletion prevented iron accumulation by reversing the significant increase in the expression of iron storage protein ferritin heavy chain (Fth), ferritin light chain (Ftl) and iron importer transferrin receptor 1 (Tfr1), as well as enhancing the expression of iron exporter ferroportin (Fpn) after IR. RPRM deletion also inhibited lipid peroxidation by abolishing the reduction of GPX4 and stearoyl coenzyme A desaturase-1 (SCD1) induced by IR. Importantly, RPRM deletion restored or even increased the expression of nuclear factor, erythroid 2 like 2 (Nrf2) in irradiated neurons. On top of that, compromised cyclic AMP response element (CRE)-binding protein (CREB) signaling was found to be responsible for the down-regulation of Nrf2 and SCD1 after irradiation, specifically, RPRM bound to CREB and promoted its degradation after IR, leading to a reduction of CREB protein level, which in turn down-regulated Nrf2 and SCD1. Thus, RPRM deletion recovered Nrf2 and SCD1 through its impact on CREB. Taken together, neuronal ferroptosis is involved in RIBI, RPRM deletion prevents IR-induced neuronal ferroptosis through restoring CREB-Nrf2/SCD1 pathways.

Disruption of cholangiocyte-B cell crosstalk by blocking the CXCL12-CXCR4 axis alleviates liver fibrosis

B cells can promote liver fibrosis, but the mechanism of B cell infiltration and therapy against culprit B cells are lacking. We postulated that the disruption of cholangiocyte-B-cell crosstalk could attenuate liver fibrosis by blocking the CXCL12-CXCR4 axis via a cyclooxygenase-2-independent effect of celecoxib. In wild-type mice subjected to thioacetamide, celecoxib ameliorated lymphocytic infiltration and liver fibrosis. By single-cell RNA sequencing and flow cytometry, CXCR4 was established as a marker for profibrotic and liver-homing phenotype of B cells. Celecoxib reduced liver-homing B cells without suppressing CXCR4. Cholangiocytes expressed CXCL12, attracting B cells to fibrotic areas in human and mouse. The proliferation and CXCL12 expression of cholangiocytes were suppressed by celecoxib. In CXCL12-deficient mice, liver fibrosis was also attenuated with less B-cell infiltration. In the intrahepatic biliary epithelial cell line HIBEpiC, bulk RNA sequencing indicated that both celecoxib and 2,5-dimethyl-celecoxib (an analog of celecoxib that does not show a COX-2-dependent effect) regulated the TGF-β signaling pathway and cell cycle. Moreover, celecoxib and 2,5-dimethyl-celecoxib decreased the proliferation, and expression of collagen I and CXCL12 in HIBEpiC cells stimulated by TGF-β or EGF. Taken together, liver fibrosis can be ameliorated by disrupting cholangiocyte-B cell crosstalk by blocking the CXCL12-CXCR4 axis with a COX-2-independent effect of celecoxib.

Short-term dietary intervention improves endothelial dysfunction induced by high-fat feeding in mice through upregulation of the AMPK-CREB signaling pathway

AIM

In addition to functioning as an energy sensor switch, AMPK plays a key role in the maintenance of cardiovascular homeostasis. However, obesity disrupts AMPK signaling, contributing to endothelial dysfunction and cardiovascular disease. This study aimed to elucidate if a short-term dietary intervention consisting in replacing the high-fat diet with a standard diet for 2 weeks could reverse obesity-induced endothelial dysfunction via AMPK-CREB activation.

METHODS

For this, 5-week-old male C57BL6J mice were fed a standard (Chow) or a high-fat (HF) diet for 8 weeks. The HF diet was replaced by the chow diet for the last 2 weeks in half of HF mice, generating 3 groups: Chow, HF and HF-Chow. Vascular reactivity and western-blot assays were performed in the thoracic aorta.

RESULTS

Returning to a chow diet significantly reduced body weight and glucose intolerance. Relaxant responses to acetylcholine and the AMPK activator (AICAR) were significantly impaired in HF mice but improved in HF-Chow mice. The protein levels of AMPKα, p-CREB and antioxidant systems (heme oxygenase-1 (HO-1) and catalase) were significantly reduced in HF but normalized in HF-Chow mice.

CONCLUSION

Improving dietary intake by replacing a HF diet with a standard diet improves AMPK-mediated responses due to the upregulation of the AMPK/CREB/HO-1 signaling pathway.

Celecoxib abrogates concanavalin A-induced hepatitis in mice: Possible involvement of Nrf2/HO-1, JNK signaling pathways and COX-2 expression

Concanavalin A (ConA) is an established model for inducing autoimmune hepatitis (AIH) in mice, mimicking clinical features in human. The aimof the current study is to explore the possible protective effect of celecoxib, a cyclooxygenase-2 inhibitor,on immunological responses elicited in the ConA model of acute hepatitis. ConA (20 mg/kg) was administered intravenously to adult male mice for 6 h. Prior to ConA intoxication, mice in the treatedgroups received daily doses of celecoxib (30 and 60 mg/kg in CMC) for 7 days. Results revealed that administration of celecoxib 60 mg/kg for 7 days significantly protected the liver from ConA-induced liver damage revealed by significant decrease in ALT and AST serum levels. Celecoxib 30 and 60 mg/kg pretreatment enhanced oxidant/antioxidant hemostasis by significantreduction of MDA and NO content and increase hepatic GSH contents and SOD activity. In addition, celecoxib 30 and 60 mg/kg caused significant increase in hepatic nuclear factor erythroid 2-related factor 2 (Nrf2) and the stress protein heme oxygenase-1 (HO-1) levels. Moreover, celecoxib 30 and 60 mg/kg inhibited the release of proinflammatory markers including IL-1β and TNF-α along with significant decrease in p-JNK, AKT phosphorylation ratio and caspase-3 expression. Besides, Con A was correlated to high expression of cyclooxygenase COX-2 and this increasing was improved by administration of celecoxib. These changes were in good agreement with improvement in histological deterioration. The protective effect of celecoxib was also associated with significant reduction of autophagy biomarkers (Beclin-1 and LC3II). In conclusion, celecoxib showed antioxidant, anti-inflammatory, anti-apoptotic and anti-autophagy activity against Con A-induced immune-mediated hepatitis. These effects could be produced by modulation of Nrf2/HO-1, IL-1B /p-JNK/p-AKT, JNK/caspase-3, and Beclin-1/LC3II signaling pathways.

Regulation of inflammation in cancer by dietary eicosanoids

BACKGROUND

Cancer is a major burden of disease worldwide and increasing evidence shows that inflammation contributes to cancer development and progression. Eicosanoids are derived from dietary polyunsaturated fatty acids, such as arachidonic acid (AA), and are mainly produced by a series of enzymatic pathways that include cyclooxygenase (COX), lipoxygenase (LOX), and cytochrome P-450 epoxygenase (CYP). Eicosanoids consist of at least several hundred individual molecules and play important roles in the inflammatory response and inflammation-related cancers.

SCOPE AND APPROACH

Dietary sources of AA and biosynthesis of eicosanoids from AA through different metabolic pathways are summarized. The bioactivities of eicosanoids and their potential molecular mechanisms on inflammation and cancer are revealed. Additionally, current challenges and limitations in eicosanoid research on inflammation-related cancer are discussed.

KEY FINDINGS AND CONCLUSIONS

Dietary AA generates a large variety of eicosanoids, including prostaglandins, thromboxane A2, leukotrienes, cysteinyl leukotrienes, lipoxins, hydroxyeicosatetraenoic acids (HETEs), and epoxyeicosatrienoic acids (EETs). Eicosanoids exert different bioactivities and mechanisms involved in the inflammation and related cancer developments. A deeper understanding of eicosanoid biology may be advantageous in cancer treatment and help to define cellular targets for further therapeutic development.

Metformin antagonizes nickel-refining fumes-induced cell pyroptosis via Nrf2/GOLPH3 pathway in vitro and in vivo

Nickel compounds, an international carcinogen in the industrial environment, increased the risk of lung inflammation even lung cancer in Ni refinery workers. Metformin has displayed the intense anti-inflammation and anti-cancer properties through regulating pyroptosis. This study was designed to explore whether Nickel-refining fumes (NiRF) can induce cell pyroptosis and how AMPK/CREB/Nrf2 mediated the protection afforded by metformin against Ni particles-induced lung impairment. Our results represented that Ni fumes exposure evoked pyroptosis via GOLPH3 and induced oxidative stress, while, metformin treatment alleviated Ni particles-mediated above changes. Moreover, nuclear factor erythroid 2-related factor 2 (Nrf2) involved in the protection of metformin, and the deficiency of Nrf2 attenuated the beneficial protection. We also determined that Nrf2 was a downstream molecule of AMPK/CREB pathway. Furthermore, male C57BL/6 mice were administered with Ni at a dose of 2 mg/kg by non-exposed endotracheal instillation and metformin (100, 200 and 300 mg/kg) via oral gavage for 4 weeks. The results indicated that NiRF promoted GOLPH3 and pyroptosis by stimulating NLRP3, caspase-1, N-GSDMD, IL-18 and IL-1β expression. However, various doses of metformin reduced GOLPH3 and the above protein levels of pyroptosis, also improved AMPK/CREB/Nrf2 expression. In summary, we found that metformin suppressed NiRF-connected GOLPH3-prompted pyroptosis via AMPK/CREB/Nrf2 signaling pathway to confer pulmonary protection.

Flurbiprofen axetil alleviates the effect of formalin-induced inflammatory pain on the cognitive function of rats with mild cognitive impairment through the AMPKα/NF-κB signaling pathway

Background

Mild cognitive impairment (MCI) as a prestage of dementia shares the most risk factors with dementia. In the present study, we explored the effect of flurbiprofen axetil on reducing the response of the central nervous system to inflammatory factors and anti-inhibiting apoptosis with the aim of developing a formalin-induced inflammatory pain model using MCI rats.

Methods

Rats were subjected to sham operation (Sham group) or formalin-induced inflammatory pain, with or without flurbiprofen axetil (10 mg/kg). MCI rats were administered D-galactose (1,000 mg/kg) for 7 days subcutaneously. Thereafter, formalin was injected subcutaneously into the hind paws of rats, while sham group was injected with only normal saline. In the formalin/flurbiprofen group (F/F group), flurbiprofen axetil was injected into the tail vein 15 min before formalin was given, and the formalin/saline group (F/S group) used normal saline instead of the drug for injection. The pain score was recorded, and the time-score curve was drawn. The escape latency time and the number of times crossing the platform were recorded. The expression of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), AMP-activated protein kinase-α (AMPKα), and nuclear factor-κB p65 (NF-κB p65) in hippocampal tissue was determined. Varying degrees of pathological changes in the hippocampal CA1 region were observed.

Results

The II phase pain score of rats in the F/F group was lower than that of the F/S group rats (P<0.05). The evasion incubation period and the number of platform crossings increased in both the F/F group and the F/S group (P<0.05), and were more significant in the F/S group. The relative content of AMPKα increased sequentially in the 3 groups, and the difference between the two comparisons of each group was statistically significant (P<0.05). The relative content of IL-6, TNF-α and NF-κB in the F/S group was greater than that of the F/F group, and the difference was statistically significant (P<0.001). Pathological morphological observations can be seen that the phenomena of nuclear consolidation, deep staining, and neuronal apoptosis occur, and the F/S group is more obvious.

Conclusions

Flurbiprofen axetil can reduce the inflammatory response and cognitive function of an inflammatory pain model using MCI rats through the AMPKα/NF-κB signaling pathway.

Pros and cons of NRF2 activation as adjunctive therapy in rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disease with an important inflammatory component accompanied by deregulated redox-dependent signaling pathways that are feeding back into inflammation. In this context, we bring into focus the transcription factor NRF2, a master redox regulator that exerts exquisite antioxidant and anti-inflammatory effects. The review does not intend to be exhaustive, but to point out arguments sustaining the rationale for applying an NRF2-directed co-treatment in RA as well as its potential limitations. The involvement of NRF2 in RA is emphasized through an analysis of publicly available transcriptomic data on NRF2 target genes and the findings from NRF2-knockout mice. The impact of NRF2 on concurrent pathologic mechanisms in RA is explained by its crosstalk with major redox-sensitive inflammatory and cell death-related pathways, in the context of the increased survival of pathologic cells in RA. The proposed adjunctive therapy targeted to NRF2 is further sustained by the existence of promising NRF2 activators that are in various stages of drug development. The interference of NRF2 with conventional anti-rheumatic therapies is discussed, including the cytoprotective effects of NRF2 for alleviating drug toxicity. From another perspective, the review presents how NRF2 activation would be decreasing the efficacy of synthetic anti-rheumatic drugs by increasing drug efflux. Future perspectives regarding pharmacologic NRF2 activation in RA are finally proposed.

AMPK and NRF2: Interactive players in the same team for cellular homeostasis?

NRF2 (Nuclear factor E2 p45-related factor 2) is a stress responsive transcription factor lending cells resilience against oxidative, xenobiotic, and also nutrient or proteotoxic insults. AMPK (AMP-activated kinase), considered as prime regulator of cellular energy homeostasis, not only tunes metabolism to provide the cell at any time with sufficient ATP or building blocks, but also controls redox balance and inflammation. Due to observed overlapping cellular responses upon AMPK or NRF2 activation and common stressors impinging on both AMPK and NRF2 signaling, it is plausible to assume that AMPK and NRF2 signaling may interdepend and cooperate to readjust cellular homeostasis. After a short introduction of the two players this narrative review paints the current picture on how AMPK and NRF2 signaling might interact on the molecular level, and highlights their possible crosstalk in selected examples of pathophysiology or bioactivity of drugs and phytochemicals.

Inhibiting AKT signaling pathway with cilostazol and meloxicam synergism for suppressing K562 cells in vitro

Despite advances in cancer treatment, chronic myeloid leukemia (CML) is still one of the leading causes of death in the world. Due to the role of inflammation in cancer promotion and progression, thus use of anti-inflammatory agents may suppress cancer cell growth. In this study, we used two anti-inflammatory drugs, cilostazol and meloxicam, for the treatment of CML. Cell viability was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the synergism occurrence was calculated by compusyn software. Annexin V/PI test and Hoechst staining were used to determine the apoptosis rate. To determine the pathway of apoptosis induction, the expression of BCL2 Associated X (Bax) and B-cell lymphoma-2 (Bcl-2) apoptotic genes and caspases activity were evaluated. The cell cycle was analyzed by propidium iodide (PI) staining and flow cytometry. Western blot analysis and immunofluorescence were performed to estimate alterations in Ak strain transforming-1 (AKT-1), phosphprylated AKT-1 (p-AKT-1), adenosine mono-phosphate-kinase (AMPK), and phosphorylated AMPK (p-AMPK) proteins and BCR/ABL and c-Myc distribution, respectively. Results showed that cilostazol, meloxicam, and their combination drug reduced cell viability (p < 0.05). Compared with control, expression of Bax and Bcl-2 decreased in treated cells, respectively (p < 0.05). The caspase-9 activity increased in treated cells compared to control cells (p < 0.001). The applied drugs decreased the protein level of p-AKT-1 while increasing the p-AMPK protein level (p < 0.05). BCR/ABL and c-Myc Protein distribution significantly decreased in treated cells. In conclusion, the combination drug had more cytotoxic effects than cilostazol and meloxicam alone and induced apoptosis by inhibiting AKT-1 activation and c-Myc reduction. Therefore using combination drugs effectively can treat cancers of CML origin.

Celecoxib has Preventive and Therapeutic Benefits against Nephrotoxicity Caused by Gentamicin in Mice

It's crucial to comprehend the impact of oxidative stress and pro-inflammatory cytokines in the gentamicin-induced kidney injury mechanism. Celecoxib was administered orally either before or after intraperitoneal therapy with gentamicin in mice. The serum levels of creatinine (SCr), blood urea nitrogen (BUN), IL-6, and TNF-α were measured by ELISA test, as well as the levels of the kidney tissue malondialdehyde (MDA), and glutathione (GSH) were also estimated spectrophotometrically. The renal expression of nuclear factor-κB (NF-κB), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and cyclooxygenase 2 (COX-2) mRNAs were evaluated by qPCR. Histopathological evaluation and Immunohistochemical examination of kidney NF-κB, IL-6, and COX-2 were also, performed. Celecoxib successfully prevented gentamicin-induced kidney damage as indicated by reducing blood BUN, SCr, and tissue MDA levels and increasing renal tissue GSH levels as well as lowering the blood IL-6 and TNF-α in comparison to mice received gentamicin. Furthermore, celecoxib has inhibited COX-2, NF-κB, IL-6, and TNF-α expression in the renal tissue. It is noteworthy that celecoxib therapy after gentamicin administration brought about substantially the same results as celecoxib treatment before gentamicin injection in mice. Our results showed the role of celecoxib as a therapeutic tool for gentamicin-induced nephrotoxicity as well as raised its beneficial prophylactic role in this medical challenge by attenuating oxidative stress and inflammation.

A Novel Pyrazolo[3,4-d]pyrimidine Induces Heme Oxygenase-1 and Exerts Anti-Inflammatory and Neuroprotective Effects

The anti-oxidant enzyme heme oxygenase-1 (HO-1) is known to exert anti-inflammatory effects. From a library of pyrazolo[3,4-d]pyrimidines, we identified a novel compound KKC080096 that upregulated HO-1 at the mRNA and protein levels in microglial BV-2 cells. KKC080096 exhibited anti-inflammatory effects via suppressing nitric oxide, interleukin-1β (IL-1β), and iNOS production in lipopolysaccharide (LPS)-challenged cells. It inhibited the phosphorylation of IKK and MAP kinases (p38, JNK, ERK), which trigger inflammatory signaling, and whose activities are inhibited by HO-1. Further, KKC080096 upregulated anti-inflammatory marker (Arg1, YM1, CD206, IL-10, transforming growth factor-β [TGF-β]) expression. In 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated mice, KKC080096 lowered microglial activation, protected the nigral dopaminergic neurons, and nigral damage-associated motor deficits. Next, we elucidated the mechanisms by which KKC080096 upregulated HO-1. KKC080096 induced the phosphorylation of AMPK and its known upstream kinases LKB1 and CaMKKbeta, and pharmacological inhibition of AMPK activity reduced the effects of KKC080096 on HO-1 expression and LPS-induced NO generation, suggesting that KKC080096-induced HO-1 upregulation involves LKB1/AMPK and CaMKKbeta/AMPK pathway activation. Further, KKC080096 caused an increase in cellular Nrf2 level, bound to Keap1 (Nrf2 inhibitor protein) with high affinity, and blocked Keap1-Nrf2 interaction. This Nrf2 activation resulted in concurrent induction of HO-1 and other Nrf2-targeted antioxidant enzymes in BV-2 and in dopaminergic CATH.a cells. These results indicate that KKC080096 is a potential therapeutic for oxidative stress- and inflammation-related neurodegenerative disorders such as Parkinson's disease.

2,5-dimethyl celecoxib induces apoptosis and autophagy via activation of ROS/JNK axis in nasopharyngeal carcinoma cells

2,5-dimethyl celecoxib (DMC), a close derivative of celecoxib, has also been reported to have anticancer effects. However, the effects and underlying molecular mechanisms of DMC with respect to nasopharyngeal carcinoma are still largely unknown. In this study, we present that DMC has displayed anticancer potency in nasopharyngeal carcinoma in vitro and in vivo. Mechanistically, we found DMC induced apoptosis and autophagy for anticancer therapy against nasopharyngeal carcinoma. Furthermore, DMC-induced autophagy could remarkably attenuate after the treatment of reactive oxygen species (ROS) scavenger N-acetyl cysteine (NAC) and c-Jun N-terminal kinase (JNK) inhibitor SP600125 (SP). Taken together, these results suggested DMC induced apoptosis and autophagic death via activation of ROS/JNK axis in NPC cells, which providing us new insights into developing potential therapeutic agents for nasopharyngeal carcinoma patients.

Topical nanocarriers for management of Rheumatoid Arthritis: A review

Rheumatoid arthritis (RA) is a systemic autoimmune disease manifested by chronic joint inflammation leading to severe disability and premature mortality. With a global prevalence of about 0.3%-1% RA is 3-5 times more prevalent in women than in men. There is no known cure for RA; the ultimate goal for treatment of RA is to provide symptomatic relief. The treatment regimen for RA involves frequent drug administration and high doses of NSAIDs such as indomethacin, diclofenac, ibuprofen, celecoxib, etorcoxib. These potent drugs often have off target effects which drastically decreases patient compliance. Moreover, conventional non-steroidal anti-inflammatory have many formulation challenges like low solubility and permeability, poor bioavailability, degradation by gastrointestinal enzymes, food interactions and toxicity. To overcome these barriers, researchers have turned to topical route of drug administration, which has superior patience compliance and they also bypass the first past effect experienced with conventional oral administration. Furthermore, to enhance the permeation of drug through the layers of the skin and reach the site of inflammation, nanosized carriers have been designed such as liposomes, nanoemulsions, niosomes, ethosomes, solid lipid nanoparticles and transferosomes. These drug delivery systems are non-toxic and have high drug encapsulation efficiency and they also provide sustained release of drug. This review discusses the effect of formulation composition on the physiochemical properties of these nanocarriers in terms of particle size, surface charge, drug entrapment and also drug release profile thus providing a landscape of topically used nanoformulations for symptomatic treatment of RA.

The Nrf2 pathway in psychiatric disorders: pathophysiological role and potential targeting

Introduction: All psychiatric disorders exhibit excitotoxicity, mitochondrial dysfunction, inflammation, oxidative stress, and neural damage as their common characteristic. The endogenous nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway is implicated in the defense mechanism against oxidative stress and has a significant role in psychiatric disorders.Areas covered: We explore the role of Nrf2 pathway and its modulators in psychiatric disorders. The literature was searched utilizing various databases such as Embase, Medline, Web of Science, Pub-Med, and Google Scholar from 2010 to 2020. The search included research articles, clinical reports, systematic reviews, and meta-analyses.Expert opinion: Environmental factors and genetic predisposition can be a trigger for the development of psychiatric disorders. Nrf2 downregulates certain inflammatory pathways and upregulates various antioxidant enzymes to maintain a balance. However, its intricate balance with NF-Kβ (Nuclear factor kappa light chain enhancer of activated B cells) and its crosstalk with the transcription factor Nrf2 is critical in severe oxidative stress. Several Nrf2 modulators are now in clinical trials and can help reduce oxidative stress and neuroinflammation. There are immense potential opportunities for these modulators to become a novel therapeutic option.

Celecoxib alleviates pathological cardiac hypertrophy and fibrosis via M1-like macrophage infiltration in neonatal mice

Cardiac hypertrophy is an adaptive response to all forms of heart disease, including hypertension, myocardial infarction, and cardiomyopathy. Cyclooxygenase-2 (COX-2) overexpression results in inflammatory response, cardiac cell apoptosis, and hypertrophy in adult heart after injury. However, immune response-mediated cardiac hypertrophy and fibrosis have not been well documented in injured neonatal heart. This study showed that cardiac hypertrophy and fibrosis are significantly attenuated in celecoxib (a selective COX-2 inhibitor)-treated P8 ICR mice after cryoinjury. Molecular and cellular profiling of immune response shows that celecoxib inhibits the production of cytokines and the expression of adhesion molecular genes, increases the recruitment of M1-like macrophage at wound site, and alleviates cardiac hypertrophy and fibrosis. Furthermore, celecoxib administration improves cardiac function at 4 weeks after injury. These results demonstrate that COX-2 inhibition promotes the recruitment of M1-like macrophages during early wound healing, which may contribute to the suppression of cardiac hypertrophy and fibrosis after injury.

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Cryoinjury successfully induces cardiac hypertrophy and fibrosis in P8 ICR mice

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COX-2 inhibition alleviates cardiac hypertrophy and fibrosis after cryoinjury

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MCP-1 significantly increases in COX-2 inhibition

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COX-2 inhibition improves cardiac repair in P8 ICR mice by recruiting M1-like macrophages

Endothelial NADPH oxidase 4 protects against angiotensin II-induced cardiac fibrosis and inflammation

Aims

Endothelial activation and inflammatory cell infiltration have important roles in the development of cardiac fibrosis induced by renin–angiotensin system activation. NADPH oxidases (Nox proteins) are expressed in endothelial cells (ECs) and alter their function. Previous studies indicated that Nox2 in ECs contributes to angiotensin II (AngII)‐induced cardiac fibrosis. However, the effects of EC Nox4 on cardiac fibrosis are unknown.

Methods and results

Transgenic (TG) mice overexpressing endothelial‐restricted Nox4 were studied alongside wild‐type (WT) littermates as controls. At baseline, Nox4 TG mice had significantly enlarged hearts compared with WT, with elongated cardiomyocytes (increased by 18.5%, P < 0.01) and eccentric hypertrophy but well‐preserved cardiac function by echocardiography and in vivo pressure–volume analysis. Animals were subjected to a chronic AngII infusion (AngII, 1.1 mg/kg/day) for 14 days. Whereas WT/AngII developed a 2.1‐fold increase in interstitial cardiac fibrosis as compared with WT/saline controls (P < 0.01), TG/AngII mice developed significant less fibrosis (1.4‐fold increase, P > 0.05), but there were no differences in cardiac hypertrophy or contractile function between the two groups. TG hearts displayed significantly decreased inflammatory cell infiltration with reduced levels of vascular cell adhesion molecule 1 in both the vasculature and myocardium compared with WT after AngII treatment. TG microvascular ECs stimulated with AngII in vitro supported significantly less leukocyte adhesion than WT ECs.

Conclusions

A chronic increase in endothelial Nox4 stimulates physiological cardiac hypertrophy and protects against AngII‐induced cardiac fibrosis by inhibiting EC activation and the recruitment of inflammatory cells.

Mice with endothelium‐specific overexpression of Nox4 (EndoNox4 TG) exhibit eccentric hypertrophy with well‐preserved cardiac function at baseline.

EndoNox4 TG mice develop significantly less interstitial cardiac fibrosis in response to chronic pressure AngII stimulation, independent of cardiac hypertrophy.

Overexpression of Nox4 in endothelial cells reduces AngII‐induced endothelial activation.

An increase in endothelial Nox4 inhibits AngII‐induced recruitment of inflammatory cells in the heart.

Observational study of people infected with SARS-Cov-2, treated with amantadine

BACKGROUND

We conducted an observational study of 15 patients from a Southeastern area of Mexico with symptoms compatible with SARS-Cov-2, which were treated with the antiviral amantadine.

METHODOLOGY

In this study, data were collected from 15 individuals with clinical symptoms of COVID-19 infection, which were treated on an ambulatory basis with 100 mg of amantadine for a period of 14 days.

RESULTS

This drug demonstrated its effectiveness, as patients recovered successfully with this treatment without the necessity of attending a hospital to use mechanical ventilation. All patients developed IgG antibodies to SARS-Cov-2.

CONCLUSION

Amantadine can be used as a viable and cost-effective alternative for treating people with severe acute respiratory syndrome (SARS-Cov-2) on an ambulatory basis, while the vaccine is not available.

An Overview of Nrf2 Signaling Pathway and Its Role in Inflammation

Inflammation is a key driver in many pathological conditions such as allergy, cancer, Alzheimer’s disease, and many others, and the current state of available drugs prompted researchers to explore new therapeutic targets. In this context, accumulating evidence indicates that the transcription factor Nrf2 plays a pivotal role controlling the expression of antioxidant genes that ultimately exert anti-inflammatory functions. Nrf2 and its principal negative regulator, the E3 ligase adaptor Kelch-like ECH- associated protein 1 (Keap1), play a central role in the maintenance of intracellular redox homeostasis and regulation of inflammation. Interestingly, Nrf2 is proved to contribute to the regulation of the heme oxygenase-1 (HO-1) axis, which is a potent anti-inflammatory target. Recent studies showed a connection between the Nrf2/antioxidant response element (ARE) system and the expression of inflammatory mediators, NF-κB pathway and macrophage metabolism. This suggests a new strategy for designing chemical agents as modulators of Nrf2 dependent pathways to target the immune response. Therefore, the present review will examine the relationship between Nrf2 signaling and the inflammation as well as possible approaches for the therapeutic modulation of this pathway.

Ethyl acetate extract from Cistus x incanus L. leaves enriched in myricetin and quercetin derivatives, inhibits inflammatory mediators and activates Nrf2/HO-1 pathway in LPS-stimulated RAW 264.7 macrophages

Cistus x incanus L. is a Mediterranean evergreen shrub used in folk medicine for the treatment of inflammatory disorders but the underlying mechanisms are not fully understood. We therefore investigated the anti-inflammatory effects of an ethyl acetate fraction (EAF) from C. x incanus L. leaves on lipopolysaccharide (LPS) activated RAW 264.7 macrophages. HPLC analysis revealed myricetin and quercetin derivatives to be the major compounds in EAF; EAF up to 1 µM of total phenolic content, was not cytotoxic and inhibited the mRNA expression of interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2) (p < 0.05) and the production of prostaglandins E₂ (PGE₂) (p < 0.05). Meanwhile, EAF triggered the mRNA expression of interleukin-10 (IL-10) and elicited the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2), as well as the expression of its main target gene, heme oxygenase-1 (HO-1) (p < 0.05). These data indicate that EAF attenuates experimental inflammation via the inhibition of proinflammatory mediators and at least in part, by the activation of Nrf2/HO-1 pathway. These effects are likely due to myricetin and quercetin derivatives but the role of other, less abundant components cannot be excluded. Further studies to confirm the relevance of our findings in animal models and to highlight the relative contribution of each component to the anti-inflammatory activity of EAF should be conducted.

Celecoxib Exerts Neuroprotective Effects in β-Amyloid-Treated SH-SY5Y Cells Through the Regulation of Heme Oxygenase-1: Novel Insights for an Old Drug

The formation and aggregation of amyloid-β-peptide (Aβ) into soluble and insoluble species represent the pathological hallmarks of Alzheimer’s disease (AD). Over the last few years, however, soluble Aβ (sAβ) prevailed over fibrillar Aβ (fAβ) as determinant of neurotoxicity. One of the main therapeutic strategies for challenging neurodegeneration is to fight against neuroinflammation and prevent free radical-induced damage: in this light, the heme oxygenase/biliverdin reductase (HO/BVR) system is considered a promising drug target. The aim of this work was to investigate whether or not celecoxib (CXB), a selective inhibitor of the pro-inflammatory cyclooxygenase-2, modulates the HO/BVR system and prevents lipid peroxidation in SH-SY5Y neuroblastoma cells. Both sAβ (6.25–50 nM) and fAβ (1.25–50 nM) dose-dependently over-expressed inducible HO (HO-1) after 24 h of incubation, reaching statistical significance at 25 and 6.25 nM, respectively. Interestingly, CXB (1–10 μM, for 1 h) further enhanced Aβ-induced HO-1 expression through the nuclear translocation of the transcriptional factor Nrf2. Furthermore, 10 μM CXB counteracted the Aβ-induced ROS production with a mechanism fully dependent on HO-1 up-regulation; nevertheless, 10 μM CXB significantly counteracted only 25 nM sAβ-induced lipid peroxidation damage in SH-SY5Y neurons by modulating HO-1. Both carbon monoxide (CORM-2, 50 nM) and bilirubin (50 nM) significantly prevented ROS production in Aβ-treated neurons and favored both the slowdown of the growth rate of Aβ oligomers and the decrease in oligomer/fibril final size. In conclusion, these results suggest a novel mechanism through which CXB is neuroprotective in subjects with early AD or mild cognitive impairment.

lncRNA Eif4g2 improves palmitate-induced dysfunction of mouse β-cells via modulation of Nrf2 activation

Chronic oxidative stress resulting from hyperlipidemia is thought to be a key pathogenic driver of pancreatic β-cell dysfunction in leading to the onset of type 2 diabetes mellitus (T2DM). Long non-coding RNAs (lncRNAs) have been increasingly recognized to regulate dysfunction within pancreatic β-cells in the context of T2DM. In the present study, we sought to comprehensively analyze the roles of lncRNAs in dysfunctional β-cells and mouse islets. Analyses of INS-1E cells were performed by RNA-seq and qRT-PCR after treating with or without 0.5 mM palmitate for 4 days, leading us to identify the novel lncRNA Eif4g2 (lncEif4g2) as a functional regulator within these cells. When we overexpressed lncEif4g2 in INS-1E β-cells and mouse islets, this was sufficient for the reversal of palmitate-mediated reductions in cell viability, insulin production, ATP production by mitochondria, and creation of intracellular reactive oxygen species (ROS) and the dysfunction of mouse islets, with nuclear factor erythroid 2 related factor 2 (Nrf2) activation also being observed. In contrast, when lncEif4g2 was knocked down this led INS-1E cells and mouse islets to become more sensitive to palmitate-induced dysfunction, with reduced Nrf2 nuclear translocation also being detected. When antioxidants were used to treat INS-1E cells and mouse islets, however, these negative effects were reversed. Additional functional analyses revealed lncEif4g2 to be capable of directly binding to miR-3074-5p in β-cells, with the expression of lncEif4g2 and miR-3074-5p being negatively correlated with one another. We further found that cAMP-responsive element binding-protein (CREB) was a miR-3074-5p target gene in these cells, thus at least in part serving as a functional mediator of the lncEif4g2/miR-3074-5p axis within dysfunctional β-cells. In summary, our results thus reveal that lncEif4g2 is able to indirectly regulate the expression of CREB via targeting miR-3074-5p in INS-1E cells and mouse islets, thereby leading to enhanced Nrf2 activation.

Network Pharmacology-Based Approach to Investigate the Mechanisms of Mahai Capsules in the Treatment of Cardiovascular Diseases

Background

Mahai capsules (MHC) have been deemed to be an effective herb combination for treatment of cardiovascular diseases (CVD) development and improvement of the life quality of CVD patients. To systematically explore the mechanisms of MHC in CVD, a network pharmacology approach mainly comprising target prediction, network construction, biological process and pathway analysis, and related diseases was adopted in this study.

Methods

We collected the bioactive compounds and potential targets of MHC through the TCMSP servers. Candidate targets related to CVD were collected from Therapeutic Targets Database and PharmGkb database and analyzed using ClueGO plugin in Cytoscape. KEGG pathway was enriched and analyzed through the EnrichR platform, and protein-protein interaction networks were calculated by STRING platform. The compound-target, target-disease, and compound-target-disease networks were constructed using Cytoscape.

Results

A total of 303 targets of the 57 active ingredients in MHC were obtained. The network analysis showed that PTGS2, PTGS1, HSP90, Scn1a, estrogen receptor, calmodulin, and thrombin were identified as key targets of MHC in the treatment of CVD. The functional enrichment analysis indicated that MHC probably produced the therapeutic effects against CVD by synergistically regulating many biological pathways, such as PI3K-Akt, TNF, HIF-1, FoxO, apoptosis, calcium, T-cell receptor, VEGF, and NF-kappa B signaling pathway.

Conclusions

In summary, the analysis of the complete profile of the pharmacological properties, as well as the elucidation of targets, networks, and pathways, can further illuminate that the underlying mechanisms of MHC in CVD might be strongly associated with its synergic regulation of inflammation, apoptosis, and immune function, and provide new clues for its future development of therapeutic strategies and basic research.

Nutraceuticals for prevention of atherosclerosis: Targeting monocyte infiltration to the vascular endothelium

Cardiovascular disease (CVD) is the leading cause of death, globally, and is a serious problem in developing countries. Preventing atherosclerosis is key to reducing the risk of developing CVD. Similar to carcinogenesis, atherogenesis can be divided into four stages: initiation, promotion, progression, and acute events. The current study focuses on the promotion stage, which is characterized by circular monocyte penetration into vascular endothelial cells, monocyte differentiation into macrophages, and the formation of foam cells. This early stage of atherogenesis is a major target for nutraceuticals. We discuss nutraceuticals that can potentially inhibit monocyte adhesion to the vascular endothelium, thereby preventing the promotional stage of atherosclerosis. The mechanisms through which these nutraceuticals prevent monocyte adhesion are classified according to the following targets: NF-κB, ROS, MAPKs, and AP-1. Additionally, we discuss promising targets for nutraceuticals that can regulate monocyte adhesion to the endothelium. PRACTICAL APPLICATIONS: Introduction of atherogenesis with initiation, promotion, progression, and acute events provide specific information and factors for each step in the development of atherosclerosis. Functional food or pharmaceutical researchers can set target stages and use them to develop materials that control atherosclerosis. In particular, because it focuses on vascular inflammation via interaction between monocytes and vascular endothelial cells, it provides specific information to researchers developing functional foods that regulate this process. Therefore, this manuscript, unlike previous papers, will provide material information and potential mechanisms of action to researchers who want to develop functional foods that control vascular inflammation rather than vascular lipids.

COX-2 as a potential biomarker and therapeutic target in melanoma

With a constantly increasing incidence, cutaneous melanoma has raised the need for a better understanding of its complex microenvironment that may further guide therapeutic options. Melanoma is a model tumor in immuno-oncology. Inflammation represents an important hallmark of cancer capable of inducing and sustaining tumor development. The inflammatory process also orchestrates the adaptative immunosuppression of tumor cells that helps them to evade immune destruction. Besides its role in proliferation, angiogenesis, and apoptosis, cyclooxygenase-2 (COX-2) is a well-known promoter of immune suppression in melanoma. COX-2 inhibitors are closely involved in this condition. This review attempts to answer two controversial questions: is COX-2 a valuable prognostic factor? Among all COX-2 inhibitors, is celecoxib a suitable adjuvant in melanoma therapy?

A journey of celecoxib from pain to cancer

The most enthralling and versatile class of drugs called the Non-steroidal anti-inflammatory (NSAIDs) showed its therapeutic utility in inflammation, beginning from the era of classic drug 'Aspirin'. NSAIDs and their well-established action based on inhibiting the COX-1 and COX-2 enzyme leads to blockage of prostaglandin pathway. They further categorized into first generation (non-selective inhibitor) and second generation (selective COX-2 inhibitors). Selective COX-2 inhibitors has advantage over non-selective in terms of their improved safety profile of gastro-intestinal tract. Rejuvenating and recent avenues for COXIBS (selective COX-2 inhibitors) explains its integrated role in identification of biochemical pain signaling as well as its pivotal key role in cancer chemotherapy. A key role player in this class is the Celecoxib (only FDA approved COXIB) a member of Biopharmaceutical classification system (BCS) II. Low solubility and bioavailability issues related with celecoxib lead to the development and advancement in the discovery and research of some possible formulation administered either orally, topically or via transdermal route. This review article intent to draw the bead on Celecoxib and it clearly explain extensive knowledge of its disposition profile, its dynamic role in cancer at cellular level and cardiovascular risk assessment. Some of the possible formulations approaches with celecoxib and its improvement aspects are also briefly discussed.

Neuroprotective effects of melatonin and celecoxib against ethanol-induced neurodegeneration: a computational and pharmacological approach

PURPOSE

Melatonin and celecoxib are antioxidants and anti-inflammatory agents that exert protective effects in different experimental models. In this study, the neuroprotective effects of melatonin and celecoxib were demonstrated against ethanol-induced neuronal injury by in silico, morphological, and biochemical approaches.

METHODS

For the in silico study, 3-D structures were constructed and docking analysis performed. For in vivo studies, rats were treated with ethanol, melatonin, and celecoxib. Brain samples were collected for biochemical and morphological analysis.

RESULTS

Homology modeling was performed to build 3-D structures for IL1β), TNFα, TLR4, and inducible nitric oxide synthase. Structural refinement was achieved via molecular dynamic simulation and processed for docking and postdocking analysis. Further in vivo experiments showed that ethanol induced marked neuronal injury characterized by downregulated glutathione, glutathione S-transferase, and upregulated inducible nitric oxide synthase. Additionally, ethanol increased the expression of TNFα and IL1β. Finally, neuronal apoptosis was demonstrated in ethanol-intoxicated animals using caspase 3 and activated JNK staining. On the other hand, melatonin and celecoxib treatment ameliorated the biochemical and immunohistochemical alterations induced by ethanol.

CONCLUSION

These results demonstrated that ethanol induced neurodegeneration by activating inflammatory and apoptotic proteins in rat brain, while melatonin and celecoxib may protect rat brain by downregulating inflammatory and apoptotic markers.

Inflammation and cardiovascular disease

Cardiovascular disease (CVD) has been associated with the so-called traditional risk factors, such as hypertension, hypercholesterolemia and cigarette smoking. Chronic inflammation, exemplified by elevated high sensitivity C-reactive protein, has been added to these risk factors for CVD as non-traditional risk factor. There are two aspects in this association. The first is whether inflammation plays a pathogenic role in traditional risk factors-mediated CVD or it is just an epiphenomenon. The second is whether chronic inflammation caused by an inflammatory disease has any impact on CVD. Accumulated data have shown that inflammation has a central and inciting role in the development of atherosclerosis leading to increased CVD risk. How inflammation contributes to CVD is a topic of continuous research where mechanisms involving both innate and adaptive immune pathways are involved. Endothelial dysfunction, oxidative stress in vascular endothelial cells, macrophage accumulation, formation of inflammasome, production of tumor necrosis factor (TNF)-a, IL-1 and IL-6 characterize the inflammatory process leading to atherogenesis. Recently clonal hematopoiesis of indeterminate potential represents a surprising and novel mechanism underlying atherogenesis. Data from chronic rheumatic inflammatory diseases exemplify the complexity of mechanisms leading to increased CVD, while they also provide evidence that anti-inflammatory biologic drugs, such as anti-TNF and anti-IL6 agents, could control atherogenesis and ameliorate CVD risk. Recent groundbreaking work using biologic anti-IL-1b therapy to treat men and women who have had a prior heart attack provides the best proof of the pathogenic contribution of inflammation in the development of CVD.

Contribution of Nrf2 Modulation to the Mechanism of Action of Analgesic and Anti-inflammatory Drugs in Pre-clinical and Clinical Stages

Despite the progress that has occurred in recent years in the development of therapies to treat painful and inflammatory diseases, there is still a need for effective and potent analgesics and anti-inflammatory drugs. It has long been known that several types of antioxidants also possess analgesic and anti-inflammatory properties, indicating a strong relationship between inflammation and oxidative stress. Understanding the underlying mechanisms of action of anti-inflammatory and analgesic drugs, as well as essential targets in disease physiopathology, is essential to the development of novel therapeutic strategies. The Nuclear factor-2 erythroid related factor-2 (Nrf2) is a transcription factor that regulates cellular redox status through endogenous antioxidant systems with simultaneous anti-inflammatory activity. This review summarizes the molecular mechanisms and pharmacological actions screened that link analgesic, anti-inflammatory, natural products, and other therapies to Nrf2 as a regulatory system based on emerging evidences from experimental disease models and new clinical trial data.

Novel nano therapeutic materials for the effective treatment of rheumatoid arthritis-recent insights

Rheumatoid arthritis (RA) is the most common complex multifactorial joint related autoimmune inflammatory disease with unknown etiology accomplished with increased cardiovascular risks. RA is characterized by the clinical findings of synovial inflammation, autoantibody production, and cartilage/bone destruction, cardiovascular, pulmonary and skeletal disorders. Pro-inflammatory cytokines such as IL-1, IL-6, IL-8, and IL-10 were responsible for the induction of inflammation in RA patients. Drawbacks such as poor efficacy, higher doses, frequent administration, low responsiveness, and higher cost and serious side effects were associated with the conventional dosage forms for RA treatment. Nanomedicines were recently gaining more interest towards the treatment of RA, and researchers were also focusing towards the development of various anti-inflammatory drug loaded nanoformulations with an aid to both actively/passively targeting the inflamed site to afford an effective treatment regimen for RA. Alterations in the surface area and nanoscale size of the nanoformulations elicit beneficial physical and chemical properties for better pharmacological activities. These drug loaded nanoformulations may enhances the solubility of poorly water soluble drugs, improves the bioavailability, affords targetability and may improve the therapeutic activity. In this regimen, the present review focus towards the novel nanoparticulate formulations (nanoparticles, nanoemulsions, solid lipid nanoparticles, nanomicelles, and nanocapsules) utilized for the treatment of RA. The recent advancements such as siRNA, peptide and targeted based nanoparticulate systems for RA treatment were also discussed. Special emphasis was provided regarding the pathophysiology, prevalence and symptoms towards the development of RA.

Cordycepin inhibits lipopolysaccharide-induced cell migration and invasion in human colorectal carcinoma HCT-116 cells through down-regulation of prostaglandin E2 receptor EP4

Prostaglandin E₂ (PGE₂), a major product of cyclooxygenase-2 (COX-2), plays an important role in the carcinogenesis of many solid tumors, including colorectal cancer. Because PGE₂ functions by signaling through PGE₂ receptors (EPs), which regulate tumor cell growth, invasion, and migration, there has been a growing amount of interest in the therapeutic potential of targeting EPs. In the present study, we investigated the role of EP4 on the effectiveness of cordycepin in inhibiting the migration and invasion of HCT116 human colorectal carcinoma cells. Our data indicate that cordycepin suppressed lipopolysaccharide (LPS)-enhanced cell migration and invasion through the inactivation of matrix metalloproteinase (MMP)-9 as well as the down-regulation of COX-2 expression and PGE₂ production. These events were shown to be associated with the inactivation of EP4 and activation of AMP-activated protein kinase (AMPK). Moreover, the EP4 antagonist AH23848 prevented LPS-induced MMP-9 expression and cell invasion in HCT116 cells. However, the AMPK inhibitor, compound C, as well as AMPK knockdown via siRNA, attenuated the cordycepin-induced inhibition of EP4 expression. Cordycepin treatment also reduced the activation of CREB. These findings indicate that cordycepin suppresses the migration and invasion of HCT116 cells through modulating EP4 expression and the AMPK-CREB signaling pathway. Therefore, cordycepin has the potential to serve as a potent anti-cancer agent in therapeutic strategies against colorectal cancer metastasis.