Baicalein reduces lipopolysaccharide-induced inflammation via suppressing JAK/STATs activation and ROS production

Palliative potential of genistein to counteract endosulfan instigated colon toxicity via regulating TLR4/MyD88, JAK1/STAT3 and NF-κB pathway: A biochemical and histological approach

Endosulfan (ESN) is an organophosphate insecticidal agent that is documented to induce various organ toxicities. Genistein (GEN) is a plant derived polyphenolic compound with excellent biological as well as pharmacological properties. This research was planned to assess the palliative potential of GEN to avert ENS prompted colonic toxicity. Albino rats (n = 36) were involved in this experiment that were divided into the control, ESN (5 mg/kg), ESN (5 mg/kg) + GEN (10 mg/kg), and GEN (10 mg/kg) alone treated group. We found that ENS intoxication upregulated the gene expression of STAT3, JAK1, TRAF6, MyD88, NF-κB, IL- IL-1β, TLR4, TNF-α, and IL-6 while reducing the gene expression of IκB. Moreover, ENS intoxication elevated the levelss of malondialdehyde (MDA) & reactive oxygen species (ROS) while decreasing the activties of glutathione reductase (GSR), catalase (CAT), heme-oxygenase-1 (HO-1), glutathione peroxidase (GPx), glutathione (GSH), superoxide dismutase (SOD), and glutathione S-transferase (GST). Furthermore, ESN administration notably escalated the concentrations of fecal calprotectin whereas reduced the concentrations of fecal elastase, lactase and sucrase. Besides, ESN intake upregulated the levels of Caspase-9, Bax and Caspase-3 while diminishing the levels of Bcl-2. Colonic histology was distorted after ESN provision. Nonetheless, GEN treatment remarkably protected the colonic tissues via regulating abovementioned irregularities owing to its marvelous anti-inflammatory, anti-apoptotic as well as antioxidant potential.

Investigating Xiaochaihu Decoction's fever-relieving mechanism via network pharmacology, molecular docking, dynamics simulation, and experiments

Xiaochaihu Decoction（XCHD）is a classic prescription for the treatment of fever, but the mechanism is not clear. In this study, We elucidated the mechanism of action through network pharmacology and molecular docking. A rat fever model was established to verify the prediction results of network pharmacology. The analysis revealed that 120 intersection targets existed between XCHD and fever. The TP53, STAT3, RELA, MAPK1, AKT1, TNF and MAPK14 as potential core targets of XCHD in fever treatment. GO and KEGG pathway enrichment analyses indicated that XCHD may act through pathways such as the AGE-RAGE signaling pathway in diabetic complications, TNF signaling pathway, IL-17 signaling pathway. Molecular docking results demonstrated that quercetin, kaempferol, β-sitosterol, stigmasterol and baicalein exhibited strong binding activity to key targets. Animal experiments showed that XCHD significantly reduced body temperature and levels of IL-1β, IL-6, TNF-α, NO, PGE2, and cAMP in rats with fever. Importantly, no significant difference was observed between the XCHD self-emulsifying nano phase plus suspension phase and XCHD group. XCHD exerts its therapeutic effects on fever through a multi-ingredient, multi-target, and multi-pathway approach.

Protective Effects of Baicalein on Lipopolysaccharide-Induced AR42J PACs through Attenuation of Both Inflammation and Pyroptosis via Downregulation of miR-224-5p/PARP1

Background

Baicalein has been used to treat inflammation-related diseases; nevertheless, its specific mechanism of action is unclear. Therefore, we examined the protective effects of baicalein on lipopolysaccharide-induced damage to AR42J pancreatic acinar cells (PACs) and determined its mechanism of action for protection.

Methods

An in vitro cell model of acute pancreatitis (AP) was established using lipopolysaccharide (LPS) (1 mg/L)-induced PACs (AR42J), and the relative survival rate was determined using the 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide (MTT) technique. Flow cytometry was applied to evaluate the apoptotic rates of AR42J PACs. The RNA and protein expression of miR-224-5p, poly ADP-ribose polymerase-1 (PARP1), nuclear transcription factor-κB65 (NF-κB65), phospho-kappa B alpha(p-IκB-α), interleukin(IL)-18R, NOD-like receptor thermal protein domain-associated protein 3 (NLRP3), gasdermin D (GSDMD), apoptosis-associated speck-like protein containing a CARD (ASC), and caspase-1 was detected based on the WB and RT-PCR assays. IL-1β, IL-6, IL-18, and TNF-α expression levels in AR42J cells were measured via ELISA method. The cell morphology was examined using the AO/EB method.

Results

The experiment confirmed a significant increase in the activity of AR42J cells treated with various doses of baicalein. Moreover, IL-1β, IL-6, TNF-α, and IL-18 expression levels in AR42J cells were dramatically reduced (P  < 0.05), while miR-224-5p level was obviously enhanced. The protein and gene expression of PARP1, NF-κB65, p-IκB-α, IL-18R, GSDMD, ASC, NLRP3, and caspase-1 was obviously decreased (P < 0.05). Apoptosis in AR42J cells was significantly reduced with significant improvement in cell morphology.

Conclusion

Baicalein may significantly alleviate LPS-induced AR42J PAC damage by inhibiting the inflammatory response and pyroptosis. Its mode of action might be linked to higher miR-224-5p expression, which inhibits the PARP1/NF-κB and NLPR3/ASC/caspase-1/GSDMD pathways.

Janus Kinase Inhibitor Brepocitinib Rescues Myelin Phagocytosis Under Inflammatory Conditions: In Vitro Evidence from Microglia and Macrophage Cell Lines

Central nervous system (CNS) injuries induce cell death and consequently the release of myelin and other cellular debris. Microglia as well as hematogenous macrophages actively collaborate to phagocyte them and undergo their degradation. However, myelin accumulation persists in the lesion site long after the injury with detrimental effects on axonal regeneration. This might be due to the presence of inhibitors of phagocytosis in the injury site. As we recently published that some proinflammatory stimuli, like interferon-γ (IFNγ) and lipopolysaccharide (LPS), inhibit myelin phagocytosis in macrophages, we have now studied the signaling pathways involved. A phagocytosis assay in Raw264.7 macrophages and N13 microglia cell lines with labeled myelin was developed with the pHrodo reagent that emits fluorescence in acidic cellular compartments (e.g.lysosomes). Pharmacological inhibition of Janus kinases (Jak) with Brepocitinib restored myelin phagocytosis and rescued the expression of genes related to phagocytosis, like triggering receptor expressed on myeloid cells 2 (TREM2), induced by IFNγ or LPS. In addition, while pharmacological inhibition of the signal transducer and activator of transcription 3 (STAT3) rescued myelin phagocytosis and the expression of phagocytosis related genes in the presence of LPS, it did not have any effect on IFNγ-treated cells. Our results show that Jak pathways participate in the inhibition of myelin phagocytosis by IFNγ and LPS. They also indicate that the resolution of inflammation is important for the clearance of cellular debris by macrophages and subsequent regenerative processes.

Verapamil and tangeretin enhances the M1 macrophages to M2 type in lipopolysaccharide-treated mice and inhibits the P-glycoprotein expression by downregulating STAT1/STAT3 and upregulating SOCS3

LPS induced sepsis is a complex process involving various immune cells and signaling molecules. Dysregulation of macrophage polarization and ROS production contributed to the pathogenesis of sepsis. PGP is a transmembrane transporter responsible for the efflux of a number of drugs and also expressed in murine macrophages. Natural products have been shown to decrease inflammation and expression of efflux transporters. However, no treatment is currently available to treat LPS induced sepsis. Verapamil and Tangeretin also reported to attenuate lipopolysaccharide-induced inflammation. However, the effects of verapamil or tangeretin on lipopolysaccharide (LPS)-induced sepsis and its detailed anti-inflammatory mechanism have not been reported. Here, we have determined that verapamil and tangeretin protects against LPS-induced sepsis by suppressing M1 macrophages populations and also through the inhibition of P-glycoprotein expression via downregulating STAT1/STAT3 and upregulating SOCS3 expression in macrophages. An hour before LPS (10 mg/kg) was administered; mice were given intraperitoneal injections of either verapamil (5 mg/kg) or tangeretin (5 mg/kg). The peritoneal macrophages from different experimental groups of mice were isolated. Hepatic, pulmonary and splenic morphometric analyses revealed that verapamil and tangeretin decreased the infiltration of neutrophils into the tissues. Verapamil and tangeritin also enhanced the activity of SOD, CAT, GRX and GSH level in all the tissues tested. verapamil or tangeretin pre-treated mice shifted M1 macrophages to M2 type possibly through the inhibition of P-glycoprotein expression via downregulating STAT1/STAT3 and upregulating SOCS3 expression. Hence, both these drugs have shown protective effects in sepsis via suppressing iNOS, COX-2, oxidative stress and NF-κB signaling in macrophages. Therefore, in our study we can summarize that mice were treated with either Vera or Tan before LPS administration cause an elevated IL-10 by the macrophages which enhances the SOCS3 expression, and thereby able to limits STAT1/STAT3 inter-conversion in the macrophages. As a result, NF-κB activity is also getting down regulated and ultimately mitigating the adverse effect of inflammation caused by LPS in resident macrophages. Whether verapamil or tangeretin offers such protection possibly through the inhibition of P-glycoprotein expression in macrophages needs clarification with the bio availability of these drugs under PGP inhibited conditions is a limitation of this study.

The mechanism of UNC-51-like kinase 1 and the applications of small molecule modulators in cancer treatment

Autophagy is a process of self-renewal in cells, which not only provides the necessary nutrients for cells, but also clears necrotic organelles. Autophagy disorders are closely related to diseases such as cancer. UNC-51-like kinase 1 (ULK1) is a serine/threonine protein kinase that plays a crucial role in receiving input from energy and nutrient sensors, activating autophagy to maintain cellular homeostasis under stressful conditions. In recent years, targeting ULK1 has become a highly promising strategy for cancer treatment. This review introduces the regulatory mechanism of ULK1 in autophagy through the AMPK/mTOR/ULK1 pathway and reviews the research progress of ULK1 activators and inhibitors and their applications in cancer treatment. In addition, we analyze the binding modes between ULK1 and modulators through virtual molecular docking, which will provide a reliable basis and theoretical guidance for the design and development of new therapeutic drugs targeting ULK1.

Baicalin and baicalein in modulating tumor microenvironment for cancer treatment: A comprehensive review with future perspectives

Cancer is a leading cause of death worldwide. The burden of cancer incidence and mortality is increasing rapidly. New approaches to cancer prevention and treatment are urgently needed. Natural products are reliable and powerful sources for anticancer drug discovery. Baicalin and baicalein, two major flavones isolated from Scutellaria baicalensis Georgi, a multi-purpose traditional medicinal plant in China, exhibit anticancer activities against multiple cancers. Of note, these phytochemicals exhibit extremely low toxicity to normal cells. Besides their cytotoxic and cytostatic activities toward diverse tumor cells, recent studies demonstrated that baicalin and baicalein modulate a variety of tumor stromal cells and extracellular matrix (ECM) in the tumor microenvironment (TME), which is essential for tumorigenesis, cancer progression and metastasis. In this review, we summarize the therapeutic potential and the mechanism of action of baicalin and baicalein in the regulation of tumor microenvironmental immune cells, endothelial cells, fibroblasts, and ECM that reshape the TME and cancer signaling, leading to inhibition of tumor angiogenesis, progression, and metastasis. In addition, we discuss the biotransformation pathways of baicalin and baicalein, related therapeutic challenges and the future research directions to improve their bioavailability and clinical anticancer applications. Recent advances of baicalin and baicalein warrant their continued study as important natural ways for cancer interception and therapy.

Androgen receptor and hyaluronan-mediated motility receptor as new molecular targets of baicalein: new molecular mechanisms for its anticancer properties

Natural compounds known as phytochemicals have served as valuable resources for the development of new anti-cancer drugs and treatment of malignancies. Among these phytochemicals, baicalein is an emerging anti-tumor flavonoid obtained from Scutellaria baicaleinsis (Lamiaceae), but its underlying mechanisms of action and molecular targets have not yet been completely elucidated. Here, we identified new mechanisms for the anti-tumor activities of baicalein, providing evidence that hyaluronan-mediated motility receptor (HMMR) and androgen receptor (AR) are new molecular targets of baicalein in human cancer cells. We observed that HMMR, known to be highly associated with poor prognosis in a wide range of human cancers, was substantially downregulated by baicalein at mRNA and protein levels. Reporter assays further revealed that the suppression of HMMR by baicalein might occur through a transcriptional regulatory mechanism with the participation of Egr-1, E2F3α, and serum response factor (SRF). We also found that baicalein significantly inhibits androgenic responses in hormone-responsive prostate cancer cells, indicating that this might be attributed to the downregulation of AR promoter activity by baicalein. Additionally, baicalein markedly induced the expression of tumor suppressive miR-30C, which might be partly involved in baicalein-mediated autophagy and anti-cancer effects. Overall, our study sheds light on new diverse mechanisms of the anti-cancer effects exhibited by baicalein, implying that baicalein could be a potential therapeutic agent against human cancers and function as an inhibitor of HMMR and AR.

Baicalein Resensitizes Multidrug-Resistant Gram-Negative Pathogens to Doxycycline

As multidrug-resistant pathogens emerge and spread rapidly, novel antibiotics urgently need to be discovered. With a dwindling antibiotic pipeline, antibiotic adjuvants might be used to revitalize existing antibiotics. In recent decades, traditional Chinese medicine has occupied an essential position in adjuvants of antibiotics. This study found that baicalein potentiates doxycycline against multidrug-resistant Gram-negative pathogens. Mechanism studies have shown that baicalein causes membrane disruption by attaching to phospholipids on the Gram-negative bacterial cytoplasmic membrane and lipopolysaccharides on the outer membrane. This process facilitates the entry of doxycycline into bacteria. Through collaborative strategies, baicalein can also increase the production of reactive oxygen species and inhibit the activities of multidrug efflux pumps and biofilm formation to potentiate antibiotic efficacy. Additionally, baicalein attenuates the lipopolysaccharide-induced inflammatory response in vitro. Finally, baicalein can significantly improve doxycycline efficacy in mouse lung infection models. The present study showed that baicalein might be considered a lead compound, and it should be further optimized and developed as an adjuvant that helps combat antibiotic resistance. IMPORTANCE Doxycycline is an important broad-spectrum tetracycline antibiotic used for treating multiple human infections, but its resistance rates are recently rising globally. Thus, new agents capable of boosting the effectiveness of doxycycline need to be discovered. In this study, it was found that baicalein potentiates doxycycline against multidrug-resistant Gram-negative pathogens in vitro and in vivo. Due to its low cytotoxicity and resistance, the combination of baicalein and doxycycline provides a valuable clinical reference for selecting more effective therapeutic strategies for treating infections caused by multidrug-resistant Gram-negative clinical isolates.

Baicalein Induces G2/M Cell Cycle Arrest Associated with ROS Generation and CHK2 Activation in Highly Invasive Human Ovarian Cancer Cells

Ovarian cancer is a lethal gynecological cancer because drug resistance often results in treatment failure. The CHK2, a tumor suppressor, is considered to be an important molecular target in ovarian cancer due to its role in DNA repair. Dysfunctional CHK2 impairs DNA damage-induced checkpoints, reduces apoptosis, and confers resistance to chemotherapeutic drugs and radiation therapy in ovarian cancer cells. This provides a basis for finding new effective agents targeting CHK2 upregulation or activation to treat or prevent the progression of advanced ovarian cancer. Here, the results show that baicalein (5,6,7-trihydroxyflavone) treatment inhibits the growth of highly invasive ovarian cancer cells, and that baicalein-induced growth inhibition is mediated by the cell cycle arrest in the G₂/M phase. Baicalein-induced G₂/M phase arrest is associated with an increased reactive oxygen species (ROS) production, DNA damage, and CHK2 upregulation and activation. Thus, baicalein modulates the expression of DNA damage response proteins and G₂/M phase regulatory molecules. Blockade of CHK2 activation by CHK2 inhibitors protects cells from baicalein-mediated G₂/M cell cycle arrest. All the results suggest that baicalein has another novel growth inhibitory effect on highly invasive ovarian cancer cells, which is partly related to G₂/M cell cycle arrest through the ROS-mediated DNA breakage damage and CHK2 activation. Collectively, our findings provide a molecular basis for the potential of baicalein as an adjuvant therapeutic agent in the treatment of metastatic ovarian cancer.

Therapeutic Potential of Bioactive Components from Scutellaria baicalensis Georgi in Inflammatory Bowel Disease and Colorectal Cancer: A Review

Scutellaria baicalensis Georgi (SBG), an herbal medicine with various biological activities, including anti-inflammatory, anticancer, antiviral, antibacterial, and antioxidant activities, is effective in treatment of colitis, hepatitis, pneumonia, respiratory infections, and allergic diseases. This herbal medicine consists of major active substances, such as baicalin, baicalein, wogonoside, and wogonin. Inflammatory bowel disease (IBD) comprises a group of inflammatory conditions of the colon and small intestine, with Crohn's disease and ulcerative colitis being the main types. IBD can lead to serious complications, such as increased risk of colorectal cancer (CRC), one of the most common cancers worldwide. Currently, there is no cure for IBD, and its incidence has been increasing over the past few decades. This review comprehensively summarizes the efficacy of SBG in IBD and CRC and may serve as a reference for future research and development of drugs for IBD and cancer treatment.

An Attention towards the Prophylactic and Therapeutic Options of Phytochemicals for SARS-CoV-2: A Molecular Insight

The novel pathogenic virus was discovered in Wuhan, China (December 2019), and quickly spread throughout the world. Further analysis revealed that the pathogenic strain of virus was corona but it was distinct from other coronavirus strains, and thus it was renamed 2019-nCoV or SARS-CoV-2. This coronavirus shares many characteristics with other coronaviruses, including SARS-CoV and MERS-CoV. The clinical manifestations raised in the form of a cytokine storm trigger a complicated spectrum of pathophysiological changes that include cardiovascular, kidney, and liver problems. The lack of an effective treatment strategy has imposed a health and socio-economic burden. Even though the mortality rate of patients with this disease is lower, since it is judged to be the most contagious, it is considered more lethal. Globally, the researchers are continuously engaged to develop and identify possible preventive and therapeutic regimens for the management of disease. Notably, to combat SARS-CoV-2, various vaccine types have been developed and are currently being tested in clinical trials; these have also been used as a health emergency during a pandemic. Despite this, many old antiviral and other drugs (such as chloroquine/hydroxychloroquine, corticosteroids, and so on) are still used in various countries as emergency medicine. Plant-based products have been reported to be safe as alternative options for several infectious and non-infectious diseases, as many of them showed chemopreventive and chemotherapeutic effects in the case of tuberculosis, cancer, malaria, diabetes, cardiac problems, and others. Therefore, plant-derived products may play crucial roles in improving health for a variety of ailments by providing a variety of effective cures. Due to current therapeutic repurposing efforts against this newly discovered virus, we attempted to outline many plant-based compounds in this review to aid in the fight against SARS-CoV-2.

The Small-Molecule compound baicalein alleviates experimental autoimmune encephalomyelitis by suppressing pathogenetic CXCR6+ CD4 cells

CXC chemokine receptor6 (CXCR6)-based immunotherapy plays a significant role in autoimmune diseases, however, little is known about possible small compounds that inhibit pathogenic CXCR6⁺ T cells for treating multiple sclerosis (MS). Baicalein, a flavonoid isolated from Scutellarin baicalensis (Huang Qin), was shown to exert therapeutic effects on MS, but the underlying mechanisms are largely unknown. In the current study, we found that baicalein inhibited Th1 and Th17 differentiation in vitro. Oral administration of baicalein (25 mg/kg) significantly reduced the disease severity and the infiltration process, decreased the extent of demyelination in EAE, and selectively blocked IL-17A production and specific antibodies (IgG and IgG₃) in MOG_35-55-induced specific immune responses. In addition, the expression of CD4 cell effectors (CD44^hiCD62L^low) and pathogenic Th17 cells was decreased by baicalein treatment. Furthermore, baicalein treatment largely decreased CXCR6⁺ CD4 and CD8 cells and prominently inhibited CXCR6⁺ Th17 cells in EAE. Taken together, the findings of this study suggest for the first time that baicalein may ameliorate EAE by suppressing pathogenetic CXCR6⁺ CD4 cells.

Xanthatin Alleviates LPS-Induced Inflammatory Response in RAW264.7 Macrophages by Inhibiting NF-κB, MAPK and STATs Activation

Xanthatin (XT) is a sesquiterpene lactone isolated from the Chinese herb Xanthium, which belongs to the Asteraceae family. In this study, we developed an inflammation model via stimulating macrophage cell line (RAW 264.7 cells) with lipopolysaccharide (LPS), which was applied to assess the anti-inflammatory effect and probable mechanisms of xanthatin. When compared with the only LPS-induced group, cells that were pretreated with xanthatin were found to decrease the amount of nitric oxide (NO), reactive oxygen species (ROS) and associated pro-inflammatory factors (TNF-α, IL-1β and IL-6), and downregulate the mRNA expression of iNOS, COX-2, TNF-α, IL-1β, and IL-6. Interestingly, phosphorylated levels of related proteins (STAT3, ERK1/2, SAPK/JNK, IκBα, p65) were notably increased only with the LPS-activated cells, while the expression of these could be reverted by pre-treatment with xanthatin in a dose-dependent way. Meanwhile, xanthatin was also found to block NF-κB p65 from translocating into the nucleus and activating inflammatory gene transcription. Collectively, these results demonstrated that xanthatin suppresses the inflammatory effects through downregulating the nuclear factor kappa-B (NF-κB), mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription (STATs) signaling pathways. Taken together, xanthatin possesses the potential to act as a good anti-inflammatory medication candidate.

Baicalein inhibits macrophage lipid accumulation and inflammatory response by activating the PPARγ/LXRα pathway

Lipid accumulation and inflammatory response are two major risk factors for atherosclerosis. Baicalein, a phenolic flavonoid widely used in East Asian countries, possesses a potential atheroprotective activity. However, the underlying mechanisms remain elusive. This study was performed to explore the impact of baicalein on lipid accumulation and inflammatory response in THP-1 macrophage-derived foam cells. Our results showed that baicalein up-regulated the expression of ATP binding cassette transporter A1 (ABCA1), ABCG1, liver X receptor α (LXRα), and peroxisome proliferator-activated receptor γ (PPARγ), promoted cholesterol efflux, and inhibited lipid accumulation. Administration of baicalein also reduced the expression and secretion of TNF-α, IL-1β, and IL-6. Knockdown of LXRα or PPARγ with siRNAs abrogated the effects of baicalein on ABCA1 and ABCG1 expression, cholesterol efflux, lipid accumulation as well as pro-inflammatory cytokine release. In summary, these findings suggest that baicalein exerts a beneficial effect on macrophage lipid accumulation and inflammatory response by activating the PPARγ/LXRα signaling pathway.

Mechanistic insights into the amelioration effects of lipopolysaccharide-induced acute lung injury by baicalein: An integrated systems pharmacology study and experimental validation

BACKGROUND

Acute lung injury is an acute progressive respiratory failure caused by several of non-cardiogenic factors which involves in excessive amplification or uncontrolled inflammatory response.

OBJECTIVES

In this study, we investigated the protective effect of baicalein against acute lung injury induced by LPS and explored the underlying mechanisms.

METHODS

Forty-eight SPF male C57BL/6 mice were randomly divided into normal group, model group, dexamethasone group and baicalein low-dose, medium-dose and high-dose groups. After 5 days of adaptive feeding, the mice were intraperitoneally injected with LPS and dissected after 12 h. Hematoxylin-eosin staining, ELISA assay, immunofluorescence assay and Western-Blot were applied to appraise microstructural changes and protein expressions of lung tissues. Systems pharmacology study was used to evaluate the protection of baicalein on acute lung injury.

FINDINGS

The results showed that baicalein administration could significantly inhibit LPS-induced lung morphological changes, inhibit inflammatory response and pyroptosis. A total of forty-three potential targets of baicalein and acute lung injury were obtained. And PI3K-Akt, TNF and NF-κB were mainly signaling pathways. It is worth mentioning that this experiment also confirmed that NLRP3, caspase-1 and other inflammasome are involved in pyroptosis.

CONCLUSION

Baicalein has protected against LPS-induced lung tissues injury via inhibiting inflammatory response and pyroptosis.

Antioxidative role of Traditional Chinese Medicine in Parkinson's disease

ETHNOPHARMACOLOGICAL RELEVANCE

Neuroprotective Traditional Chinese Medicine (TCM) has been practiced in alternative medicine from early days. TCM-derived neuroprotective compounds, such as Chrysin, Cannabidiol, Toonasinoids, and β-asaron, exert significant effectiveness's towards Parkinson's disease (PD). Further, these neuroprotective TCM showed antioxidative, anti-inflammatory, anti-tumor, anti-septic, analgesic properties. Recent research showed that the reduction in the reactive oxygen species (ROS) decreased the α-synuclein (α-syn) toxicity and enhanced the dopaminergic neuron regenerations, the main hallmarks of PD. Therefore, the neuroprotective effects of novel TCM due to its antiradical activities needed deep investigations.

AIMS OF THE STUDY

This review aims to enlighten the neuroprotective TCM and its components with their antioxidative properties to the scientific community for future research.

METHOD

The relevant information on the neuroprotective TCM was gathered from scientific databases (PubMed, Web of Science, Google Scholar, ScienceDirect, SciFinder, Wiley Online Library, ACS Publications, and CNKI). Information was also gained from MS and Ph.D. thesis, books, and online databases. The literature cited in this review dates from 2001 to June 2, 0201.

RESULTS

Novel therapies for PD are accessible, mostly rely on Rivastigmine and Donepezil, offers to slow down the progression of disease at an early stage but embraces lots of disadvantages. Researchers are trying to find a potential drug against PD, which is proficient at preventing or curing the disease progress, but still needed to be further identified. Oxidative insult and mitochondrial dysfunction are thought to be the main culprit of neurodegenerations. Reactive oxygen species (ROS) are the only causative agent in all interactions, leading to PD, from mitochondrial dysfunctions, α-syn aggregative toxicity, and DA neurons degenerations. It is evident from the redox balance, which seems an imperative therapeutic approach against PD and was necessary for the significant neuronal activities.

CONCLUSION

Our study is explaining the newly discovered TCM and their neuroprotective and antioxidative properties. But also bring up the possible treatment approaches against PD for future researchers.

Therapeutic benefits of flavonoids against neuroinflammation: a systematic review

Flavonoids are an important class of natural polyphenolic compounds reported to exert beneficial effects in cardiovascular and metabolic diseases, cancer, autoimmune and neurological disorders. Flavonoids possess potential antioxidant, anti-inflammatory, antiapoptotic and immuno-modulation properties. Intriguingly, the importance of flavonoids in different neurological disorders is gaining more attention due to the safety, better pharmacokinetic profile and blood-brain barrier penetration, cost-effectiveness and readiness for clinical uses/trials. Many in vitro and in vivo research studies have established the neuroprotective mechanism of flavonoids in the central nervous system (CNS) diseases. The present review summarizes the benefits of various classes of flavonoids (flavones, flavonols, flavanones, anthocyanidins, isoflavones, flavanols), chemical nature, classification, their occurrence and distribution, pharmacokinetics and bioavailability. The manuscript also presents available evidences relating to the role of flavonoids in regulating key signaling pathways such as nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway, mitogen-activated protein kinase (MAPK) pathway, Janus kinase and signal transducer and activator of transcription proteins (JAK/STAT) pathway, Toll-like receptors (TLR) pathway, nuclear factor erythroid 2-related factor 2 (Nrf2) pathway and cAMP response element-binding protein (CREB) pathway involved in neuroinflammation associated with major neurological disorders. Literature search was conducted using electronic databases like Google Scholar, Scopus, PubMed central, Springer search and Web of science. Chemical structures used in the present analysis were drawn using Chemdraw Professional 15.0 software. This collective information provides comprehensive knowledge on disease pathways and therapeutic benefits of flavonoids in neurological disorders, druggability and future scope for research.

Dual-Targeted Nanoplatform Regulating the Bone Immune Microenvironment Enhances Fracture Healing

The immune system and skeletal system are closely linked. Macrophages are one of the most important immune cells for bone remodeling, playing a prohealing role mainly through M2 phenotype polarization. Baicalein (5,6,7-trihydroxyflavone, BCL) has been well documented to have a noticeable promotion effect on M2 macrophage polarization. However, due to the limitations in targeted delivery to macrophages and the toxic effect on other organs, BCL has rarely been used in the treatment of bone fractures. In this study, we developed mesoporous silica and Fe₃O₄ composite-targeted nanoparticles loaded with BCL (BCL@MMSNPs-SS-CD-NW), which could be magnetically delivered to the fracture site. This induced macrophage recruitment in a targeted manner, polarizing them toward the M2 phenotype, which was demonstrated to induce mesenchymal stem cells (MSCs) toward osteoblastic differentiation. The mesoporous silicon nanoparticles (MSNs) were prepared with surface sulfhydrylation and amination modification, and the mesoporous channels were blocked with β-cyclodextrin. The outer layer of the mesoporous silicon was added with an amantane-modified NW-targeting peptide to obtain the targeted nanosystem. After entering macrophages, BCL could be released from nanoparticles since the disulfide linker could be cleaved by intracellular glutathione (GSH), resulting in the removal of cyclodextrin (CD) gatekeeper, which is a key element in the pro-bone-remodeling functions such as anti-inflammation and induction of M2 macrophage polarization to facilitate osteogenic differentiation. This nanosystem passively accumulated in the fracture site, promoting osteogenic differentiation activities, highlighting a potent therapeutic benefit with high biosafety.

Anti-Inflammatory Mechanisms of Fucoidans to Treat Inflammatory Diseases: A Review

Fucoidans are sulfated heteropolysaccharides found in the cell walls of brown seaweeds (Phaeophyceae) and in some marine invertebrates. Generally, fucoidans are composed of significant amounts of L-fucose and sulfate groups, and lesser amounts of arabinose, galactose, glucose, glucuronic acid, mannose, rhamnose, and xylose. In recent years, fucoidans isolated from brown seaweeds have gained considerable attention owing to their promising bioactive properties such as antioxidant, immunomodulatory, anti-inflammatory, antiobesity, antidiabetic, and anticancer properties. Inflammation is a complex immune response that protects the organs from infection and tissue injury. While controlled inflammatory responses are beneficial to the host, leading to the removal of immunostimulants from the host tissues and restoration of structural and physiological functions in the host tissues, chronic inflammatory responses are often associated with the pathogenesis of tumor development, arthritis, cardiovascular diseases, diabetes, obesity, and neurodegenerative diseases. In this review, the authors mainly discuss the studies since 2016 that have reported anti-inflammatory properties of fucoidans isolated from various brown seaweeds, and their potential as a novel functional material for the treatment of inflammatory diseases.

Baicalein ameliorates ischemic brain damage through suppressing proinflammatory microglia polarization via inhibiting the TLR4/NF-κB and STAT1 pathway

Microglial polarization mediated neuroinflammation plays an important role in the pathological process of stroke. The aim of this study is to determine whether baicalein indirectly ameliorates neuronal injury through modulating microglial polarization after stroke and if so, then by what mechanism. The effects of baicalein on microglial polarization were revealed through the middle cerebral artery occlusion mouse model (MCAO, n = 6), the lipopolysaccharide (LPS) + interferon-γ (IFN-γ) and oxygen-glucose deprivation (OGD) induced neuroinflammatory microglia model (BV2, n = 3), respectively. Mice were treated with baicalein (100 mg/kg, i.g.) after reperfusion, and followed by daily administrations for 3 days. Results showed that the infarct volumes at 3 d in vehicle and baicalein-treated MCAO mice were 91.18 ± 4.02% and 55.36 ± 4.10%. Baicalein improved sensorimotor functions (p < 0.01) after MCAO. Real-time PCR revealed that baicalein decreased proinflammatory markers expression (p < 0.05), while elevated the anti-inflammatory markers (p < 0.05) in vivo and in vitro. Both western blot and immunofluorescent staining further confirmed that baicalein reduced proinflammatory marker CD16 levels (p < 0.01) and enhanced anti-inflammatory marker CD206 or Arg-1 levels (p < 0.05). Notably, baicalein suppressed the release of proinflammatory cytokines (p < 0.05) and nitric oxide (NO, p < 0.001). Mechanistically, baicalein prevented increases in TLR4 protein levels (p < 0.001), the phosphorylation of IKBα and p65 (p < 0.01), and the nuclear translocation of NF-κB p65 (p < 0.05). The NF-κB inhibitor, BAY 11-7085, enhanced the inhibitory effect of baicalein on the proinflammatory microglial polarization. Baicalein also inhibited the phosphorylation of signal transducer and activator of transcription 1 (STAT1, p < 0.001). A microglia-neuron co-culture system revealed that baicalein driven neuroprotection against OGD induced neuronal damage through modulating microglial polarization (p < 0.05). Baicalein indirectly ameliorates neuronal injury after stroke by polarizing microglia toward the anti-inflammatory phenotype via inhibition of the TLR4/NF-κB pathway and down-regulation of phosphorylated STAT1, suggesting that baicalein might serve a potential therapy for stroke.

Anti-metastatic Effects of Baicalein by Targeting STAT3 Activity in Breast Cancer Cells

Signal transducer and activator of transcription 3 (STAT3) is considered a potential target for cancer treatment because of its relationship with cellular transformation and tumor initiation and progression. In this study, we aimed to identify a new anti-cancer drug candidate from natural products by targeting STAT3 activity. Using STAT3-luciferase reporter cell line, we screened the chemical library of natural products and found that baicalein, a flavone isolated from the roots of Scutelleria baicalensis, strongly suppressed STAT3 activity in breast cancer cells. Baicalein inhibited STAT3 transcriptional activity and its phosphorylation, and further exhibited anti-proliferative effects in breast cancer cells. Moreover, baicalein suppressed the production of interleukin (IL)-6 and the metastatic potential of breast cancer cells both in vitro and in vivo. Collectively, our study suggests baicalein as an attractive phytochemical compound for reducing metastatic potential of breast cancer cells by regulating STAT3 activity.

A short course of tofacitinib sustains the immunoregulatory effect of CTLA4-Ig in the presence of inflammatory cytokines and promotes long-term survival of murine cardiac allografts

Costimulation blockade-based regimens are a promising strategy for management of transplant recipients. However, maintenance immunosuppression via CTLA4-Ig monotherapy is characterized by high frequency of rejection episodes. Recent evidence suggests that inflammatory cytokines contribute to alloreactive T cell activation in a CD28-independent manner, a reasonable contributor to the limited efficacy of CTLA4-Ig. In this study, we investigated the possible synergism of a combined short-term inhibition of cytokine signaling and CD28 engagement on the modulation of rejection. Our results demonstrate that the JAK/STAT inhibitor tofacitinib restored the immunomodulatory effect of CTLA4-Ig on mouse alloreactive T cells in the presence of inflammatory cytokines. Tofacitinib exposure conferred dendritic cells with a tolerogenic phenotype reducing their cytokine secretion and costimulatory molecules expression. JAK inhibition also directly affected T cell activation. In vivo, the combination of CTLA4-Ig and tofacitinib induced long-term survival of heart allografts and, importantly, it was equally effective when using grafts subjected to prolonged ischemia. Transplant survival correlated with a reduction in effector T cells and intragraft accumulation of regulatory T cells. Collectively, our studies demonstrate a powerful synergism between CTLA4-Ig and tofacitinib and suggest their combined use is a promising strategy for improved management of transplanted patients.

Anti-Inflammation Activity of Flavones and Their Structure-Activity Relationship

Flavones are an important class of bioactive constituents in foods, and their structural diversity enables them to interact with different targets. In particular, flavones are known for their anti-inflammatory activity. Herein, we summarized commonly applied in vitro, in vivo, and clinical models in testing anti-inflammatory activity of flavones. The anti-inflammatory structure-activity relationship of flavones was systematically mapped and supported with cross comparisons of that with flavanones, flavanols, and isoflavones. Hydroxyl groups (-OH) are indispensable for the anti-inflammatory function of flavones, and -OH at the C-5 and C-4' positions enhance while -OH at the C-6, C-7, C-8, and C-3' positions attenuate their activity. Moreover, the C2-C3 single bond, -OH at the C-3 and B-ring positions undermine flavone aglycones' activity. Most of the flavone aglycones function through NF-κB, MAPK, and JNK-STAT pathways, and their possible cell binding targets are kinase, aryl hydrocarbon receptor (AhR), G-protein coupled receptors, and estrogen receptors. However, the structure and anti-inflammatory activity relationship of flavones were unclear, and further research shall be conducted to close the gap in order to guide development of evidence-based functional foods.

Gegen Qinlian decoction relieved DSS-induced ulcerative colitis in mice by modulating Th17/Treg cell homeostasis via suppressing IL-6/JAK2/STAT3 signaling

BACKGROUND

Gegen Qinlian decoction (GQ) is a traditional Chinese herbal prescription that has been widely used for the treatment of bacterial dysentery and enteric typhoid fever. Recently, GQ has been clinically reported to be a potential candidate for the treatment of ulcerative colitis (UC). However, the immunoregulatory function of GQ in the treatment of UC has not been fully elucidated.

PURPOSE

This study focused on the role of immune imbalance in the pathogenesis of UC and the immunomodulatory effect of GQ in the treatment of UC.

METHODS

The UC model was established by treating female mice with 3.0% dextran sulfate sodium (DSS) for 7 days, and GQ was orally administered at dosages of 1.5 and 7.5 g/kg/day. Inflammatory factors were detected by ELISA and qRT-PCR. Treg and Th17 cell dysregulation was analyzed by qRT-PCR, immunohistochemistry and flow cytometry. Proteins related to IL-6/JAK2/STAT3 signaling were detected by western blotting.

RESULTS

GQ significantly alleviated the symptoms of UC mice and suppressed the activity of myeloperoxidase (MPO). Furthermore, the production of proinflammatory factors, such as IL-1β, TNF-α and IL-6, was dramatically reduced after GQ administration. Furthermore, GQ improved the infiltration of Treg and Th17 cells into the colons and decreased the expression of inflammatory factors, such as TGF-β1 and IL-17. The frequencies of Treg and Th17 cells in the Peyer's patches and spleen were reduced by GQ administration; however, GQ had no significant regulatory effect on normal mice. The western blotting results showed that GQ markedly suppressed the phosphorylation of JAK2 and STAT3 and decreased the transcription function of phosphorylated STAT3.

CONCLUSIONS

Taken together, these results indicated that GQ alleviated DSS-induced UC by suppressing IL-6/JAK2/STAT3 signaling to restore Treg and Th17 cell homeostasis in colonic tissue.

The main bioactive compounds of Scutellaria baicalensis Georgi. for alleviation of inflammatory cytokines: A comprehensive review

Scutellaria baicalensis Georgi., a plant used in traditional Chinese medicine, has multiple biological activities, including anti-inflammatory, antiviral, antitumor, antioxidant, and antibacterial effects, and can be used to treat respiratory tract infections, pneumonia, colitis, hepatitis, and allergic diseases. The main active substances of S. baicalensis, baicalein, baicalin, wogonin, wogonoside, and oroxylin A, can act directly on immune cells such as lymphocytes, macrophages, mast cells, dendritic cells, monocytes, and neutrophils, and inhibit the production of the inflammatory cytokines IL-1β, IL-6, IL-8, and TNF-α, and other inflammatory mediators such as nitric oxide, prostaglandins, leukotrienes, and reactive oxygen species. The molecular mechanisms underlying the immunomodulatory and anti-inflammatory effects of the active compounds of S. baicalensis include downregulation of toll-like receptors, activation of the Nrf2 and PPAR signaling pathways, and inhibition of the nuclear thioredoxin system and inflammation-associated pathways such as those of MAPK, Akt, NFκB, and JAK-STAT. Given that in addition to the downregulation of cytokine production, the active constituents of S. baicalensis also have antiviral and antibacterial effects, they may be more promising candidate therapeutics for the prevention of infection-related cytokine storms than are drugs having only antimicrobial or anti-inflammatory activities.

Testosterone regulates the intracellular bacterial community formation of uropathogenic Escherichia coli in prostate cells via STAT3

BACKGROUND

UPEC can internalize clonally in prostate to form biofilm-like intracellular bacterial communities (IBCs) for recurrent or chronic infection. We previously indicated that the exposure of prostate cells to testosterone could suppress UPEC invasion and their persistent survival within cells by effectively inhibiting the JAK/STAT1 signaling pathway. However, the regulatory mechanism by which testosterone affects UPEC-induced prostatitis via STAT3, another latent transcription factor signaling pathway is still unclear. The present study aimed to clarify the role of STAT3 in the process of UPEC-induced inflammation and colonization in prostate epithelial cells.

METHODS

The effects of testosterone-mediated inhibition were compared between the prostatitis by different UPEC strains (CFT073 and J96) through the specific GFP-UPEC-infected prostate cell model. Fluorescence microscopy was used for UPEC IBCs detection and quantifying, and Flow cytometry, RT-PCR and western blotting were used for analyzing related gene and protein expressions. Pretreatment of JAK and STAT3 inhibitors were also applied to verify the regulation of transduction pathway in testosterone-mediated anti-UPEC infection.

RESULTS

This study revealed that testosterone effectively suppresses UPEC infection and IBC formation in prostate cells through the JAK/STAT3 pathway. The results show that CFT073 and J96 UPEC infection rates and colony numbers were dose-dependently reduced in RWPE-1 cells pretreated with 5 and 20 μg/mL testosterone at 0 and 24 h post-infection. Further, testosterone reduced the amounts of UPEC infecting and surviving within the prostate cells, as well as suppressed the size of IBCs formed. We demonstrated that pretreating testosterone effectively inhibited UPEC infection along with dose-dependent suppression of STAT3 and the phosphorylated-STAT3 expression in prostate cells, especially in 24 h J96 UPEC infected groups. The STAT inhibitor, SOCS3 also up-regulated at the same time. In addition, we pretreated the JAK1 or STAT3 inhibitor with testosterone to block the signaling transduction before CFT073 and J96 UPEC infection, and found the significant restoring in both the sizes of IBCs and bacterial numbers in RWPE-1 cells. Therefore, our results suggest that the suppression of STAT3 by testosterone treatment attenuate UPEC growing within IBCs and interfere with their infection to prostate cells.

CONCLUSIONS

Overall, our study demonstrates that testosterone suppresses the initial infection of prostate epithelial cells by UPEC and reduces the survival of UPEC within IBCs after infection. These results indicate a critical role for STAT3 in facilitating UPEC infection and persistence, and its participation in driving testosterone-suppressive responses in prostate epithelial cells. In conclusion, this study suggests that testosterone may be beneficial in treating clinically recurrent UPEC infections and, thus, the persistent recurrence of prostatic inflammation.

Intracellular ROS Scavenging and Anti-Inflammatory Activities of Oroxylum indicum Kurz (L.) Extract in LPS plus IFN-γ-Activated RAW264.7 Macrophages

Oroxylum indicum (L.) Kurz has been used as plant-based food and herbal medicine in many Asian countries. The aim of the present study was to examine the antioxidant and anti-inflammatory activities of O. indicum extract (O. indicum) in RAW264.7 cells activated by LPS plus IFN-γ. The phytochemical compounds in O. indicum were identified by GC-MS and LC-MS/MS. Five flavonoids (luteolin, apigenin, baicalein, oroxylin A, and quercetin) and 27 volatile compounds were found in O. indicum. O. indicum presented antioxidant activities, including reducing ability by FRAP assay and free radical scavenging activity by DPPH assay. Moreover, O. indicum also suppressed LPS plus IFN-γ-activated reactive oxygen species generation in RAW264.7 macrophages. It possessed the potent anti-inflammatory action through suppressing nitric oxide (NO) and IL-6 secretion, possibly due to its ability to scavenge intracellular ROS. The synchrotron radiation-based Fourier transform infrared (SR-FTIR) spectroscopy results showed the alteration of signal intensity and integrated areas relating to lipid and protein of the activated RAW264.7 macrophages compared to unactivated cells. This is the first report of an application of the SR-FTIR technique to evaluate biomolecular changes in activated RAW264.7 cells. Our results indicate that O. indicum may be used as a potential source of nutraceutical for the development of health food supplement or a novel anti-inflammatory herbal medicine.

Therapeutic aspects of AMPK in breast cancer: Progress, challenges, and future directions

Breast cancer is the most ubiquitous type of neoplasms among women worldwide. Molecular aberrations associated with breast development and progressions have been extensively investigated in recent years. An AMP-activated kinase (AMPK) initially identified as a cellular energy sensor that plays a crucial role in cellular energy homeostasis. Intensive research over the last decade about the molecular mechanisms of AMPK has demonstrated that AMPK mediated diverse biological functions are achieved through phosphorylation and regulation of multiple downstream signaling molecules in normal tissue. Downregulation of AMPK activity or decreased level involved in the promotion of breast tumorigenesis, and thus activation of AMPK found to oppose tumor progression. In this review, we epitomize the recent advances in exploring the tumor suppressor function of AMPK pathways. Besides, we discuss the developments in the area of AMPK activator and its molecular mechanisms for breast cancer treatment.

Corosolic acid attenuates cardiac fibrosis following myocardial infarction in mice

Corosolic acid (CRA) is a pentacyclic triterpenoid isolated from Lagerstroemia speciosa. The aim of the present study was to determine whether CRA reduces cardiac remodelling following myocardial infarction (MI) and to elucidate the underlying mechanisms. C57BL/6J mice were randomly divided into control (PBS-treated) or CRA-treated groups. After 14 days of pre-treatment, the mice were subjected to either sham surgery or permanent ligation of the left anterior descending artery. Following surgery, all animals were treated with PBS or CRA (10 or 20 mg/kg/day) for 4 weeks. After 4 weeks, echocardiographic, haemodynamic, gravimetric, histological and biochemical analyses were conducted. The results revealed that, upon MI, mice with CRA treatment exhibited decreased mortality rates, improved ventricular function and attenuated cardiac fibrosis compared with those in control mice. Furthermore, CRA treatment resulted in reduced oxidative stress, inflammation and apoptosis, as well as inhibited the transforming growth factor β1/Smad signalling pathway activation in cardiac tissue. In vitro studies further indicated that inhibition of AMP-activated protein kinase α (AMPKα) reversed the protective effect of CRA. In conclusion, the study revealed that CRA attenuated MI-induced cardiac fibrosis and dysfunction through modulation of inflammation and oxidative stress associated with AMPKα.

Baicalein Is a Phytohormone that Signals Through the Progesterone and Glucocorticoid Receptors

While flavonoids have been studied extensively for estrogen receptor activity, they have not been well studied for their ability to modify progesterone receptor (PR) and glucocorticoid receptor (GR) signaling. Three flavonoid compounds, tangeretin, wogonin, and baicalein, were selected for testing for PR and GR activity based on their structural similarity to known phytoprogesterone-like compounds. Each compound was docked in the binding pocket of PR and GR. Of these compounds, baicalein was predicted to be most likely to bind to both receptors. A fluorescence polarization competitive binding assay for PR and GR confirmed that baicalein binds to both the PR and GR with IC₅₀ values of 15.30 μM and 19.26 μM, respectively. In Ishikawa PR-B and T47D cells, baicalein acted as a PR antagonist in a hormone response element (HRE) luciferase (Luc) assay. In OVCAR5 cells, which only express GR, baicalein was a GR agonist via an HRE/Luc assay and induced GR target genes, FKBP5 and GILZ. RU486, a PR and GR antagonist, abrogated baicalein's activity in OVCAR5 cells, confirming baicalein's activity is mediated through the GR. In vivo, baicalein administered intraperitoneally to female mice twice a week for 4 weeks at a dose of 25 mg/kg induced the GR target gene GILZ in the reproductive tract, which was blocked by RU486. In summary, baicalein has PR antagonist and GR agonist activity in vitro and demonstrates GR agonist activity in the uterus in vivo.

Broussonin E suppresses LPS-induced inflammatory response in macrophages via inhibiting MAPK pathway and enhancing JAK2-STAT3 pathway

Macrophages play an important role in inflammation, and excessive and chronic activation of macrophages leads to systemic inflammatory diseases, such as atherosclerosis and rheumatoid arthritis. In this paper, we explored the anti-inflammatory effect of broussonin E, a novel phenolic compound isolated from the barks ofBroussonetia kanzinoki, and its underlying molecular mechanisms. We discovered that Broussonin E could suppress the LPS-induced pro-inflammatory production in RAW264.7 cells, involving TNF-α, IL-1β, IL-6, COX-2 and iNOS. And broussonin E enhanced the expressions of anti-inflammatory mediators such as IL-10, CD206 and arginase-1 (Arg-1) in LPS-stimulated RAW264.7 cells. Further, we demonstrated that broussonin E inhibited the LPS-stimulated phosphorylation of ERK and p38 MAPK. Moreover, we found that broussonin E could activate janus kinase (JAK) 2, signal transducer and activator of transcription (STAT) 3. Downregulated pro-inflammatory cytokines and upregulated anti-inflammatory factors by broussonin E were abolished by using the inhibitor of JAK2-STAT3 pathway, WP1066. Taken together, our results showed that broussonin E could suppress inflammation by modulating macrophages activation statevia inhibiting the ERK and p38 MAPK and enhancing JAK2-STAT3 signaling pathway, and can be further developed as a promising drug for the treatment of inflammation-related diseases such as atherosclerosis.

12-HETE is a regulator of PGE2 production via COX-2 expression induced by a snake venom group IIA phospholipase A2 in isolated peritoneal macrophages

The snake venom miotoxin (MT)-III is a group IIA secreted phospholipase A₂ (sPLA₂) with pro-inflammatory activities. Previous studies have demonstrated that MT-III has the ability to stimulate macrophages to release inflammatory lipid mediators derived from arachidonic acid metabolism. Among them, we highlight prostaglandin (PG)E₂ produced by the cyclooxygenase (COX)-2 pathway, through activation of nuclear factor (NF)-κB. However, the mechanisms coordinating this process are not fully understood. This study investigates the regulatory mechanisms exerted by other groups of bioactive eicosanoids derived from 12-lipoxygenase (12-LO), in particular 12-hydroxyeicosatetraenoic (12-HETE), on group IIA sPLA₂-induced (i) PGE₂ release, (ii) COX-2 expression, and (iii) activation of signaling pathways p38 mitogen-activated protein kinases(p38MAPK), protein C kinase (PKC), extracellular signal-regulated kinase 1/2 (ERK1/2), and NF-κB. Stimulation of macrophages with group IIA sPLA₂ resulted in release of 12-HETE without modification of 12-LO protein levels. Pre-treatment of these cells with baicalein, a 12-LO inhibitor, decreased the sPLA₂-induced PGE₂ production, significantly reduced COX-2 expression, and inhibited sPLA₂-induced ERK; however, it did not affect p38MAPK or PKC phosphorylation. In turn, sPLA₂-induced PGE₂ release and COX-2 expression, but not NF-κB activation, was attenuated by pre-treating macrophages with PD98059 an inhibitor of ERK1/2. These results suggest that, in macrophages, group IIA sPLA₂-induced PGE₂ release and COX-2 protein expression are distinctly mediated through 12-HETE followed by ERK1/2 pathway activation, independently of NF-κB activation. These findings highlight an as yet undescribed mechanism by which 12-HETE regulates one of the distinct signaling pathways for snake venom group IIA sPLA₂-induced PGE₂ release and COX-2 expression in macrophages.

Systems pharmacology-based study of Tanreqing injection in airway mucus hypersecretion

ETHNOPHARMACOLOGICAL RELEVANCE

Mucus hypersecretion (MH) is recognized as a key pathophysiological and clinical feature of many airway inflammatory diseases. MUC5AC is a major component of airway mucus. Tanreqing injection (TRQ) is a widely used herbal formula for the treatment of respiratory inflammations for years in China. However, a holistic network pharmacology approach to understanding its therapeutic mechanisms against MH has not been pursued.

AIM OF THE STUDY

This study aimed to explore the systems-level potential active compounds and therapeutic mechanisms of TRQ in the treatment of MH.

MATERIALS AND METHODS

We established systems pharmacology-based strategies comprising compound screenings, target predictions, and pathway identifications to speculate the potential active compounds and therapeutic targets of TRQ. We also applied compound-target and target-disease network analyses to evaluate the possible action mechanisms of TRQ. Then, lipopolysaccharide (LPS)-induced Sprague-Dawley (SD) rat model was constructed to assess the effect of TRQ in the treatment of MH and to validate the possible molecular mechanisms as predicted in systems pharmacology approach.

RESULTS

The comprehensive compound collection successfully generated 55 compound candidates from TRQ. Among them, 11 compounds with high relevance to the potential targets were defined as representative and potential active ingredients in TRQ formula. Target identification revealed 172 potential targets, including pro-inflammatory cytokines of tumor necrosis factor α (TNF-α), interleukin (IL)-6, and IL-8. Pathway analyses uncovered the possible action of TRQ in the regulation of IL-17 signaling pathway and its downstream protein MUC5AC. Then in vivo experiment indicated that TRQ could significantly inhibit LPS stimulated MUC5AC over-production as well as the expression of TNF-α, IL-6, IL-8, and IL-17A, in both protein and mRNA levels.

CONCLUSIONS

Based on the systems pharmacology method and in vivo experiment, our work provided a general knowledge on the potential active compounds and possible therapeutic targets of TRQ formula in its anti-MH process. This work might suggest directions for further research on TRQ and provide more insight into better understanding the chemical and pharmacological mechanisms of complex herbal prescriptions in a network perspective.

Baicalein and baicalin promote antitumor immunity by suppressing PD-L1 expression in hepatocellular carcinoma cells

Blocking the PD-L1/PD-1 pathway to prevent the immune evasion of tumor cells is a powerful approach for treating multiple cancers, including hepatocellular carcinoma (HCC). Previous studies have shown that baicalein and baicalin are directly cytotoxic to some tumors, here we demonstrate that in addition to direct cytotoxicity, these two flavonoids stimulate the T cell mediated immune response against tumors through reduction of PD-L1 expression in cancer cells. Interestingly, more significant tumor regression was observed in BALB/c mice than in BALB/c-nu/nu mice after baicalein and baicalin treatment. PD-L1 upregulation induced by interferon-γ (IFN-γ) was significantly inhibited by these two flavonoids in vitro. Both baicalein and baicalin enhanced the cytotoxicity of T cells to eliminate tumor cells, which was abrogated after HCC cells were transfected with a PD-L1 overexpression plasmid or after T cells were pretreated with an anti-PD-1 blocking antibody. Further mechanistic research indicated that the IFN-γ-induced expression and promoter activity of PD-L1 were suppressed by these two flavonoids, and these effects were mediated by STAT3 activity inhibition. Therefore, baicalein and baicalin decreased STAT3 activity, further downregulated IFN-γ-induced PD-L1 expression and subsequently restored T cell sensitivity to kill tumor cells. Our findings provide novel insight into the anticancer effects of baicalein and baicalin through which tumor growth is inhibited by PD-L1 expression downregulation and suggest that these flavonoids have great potential for clinical treatment.

[Calenduloside E inhibits lipopolysaccharide-induced inflammatory response by inhibiting activation of ROS-mediated JAK1-stat3 signaling pathway in RAW264.7 cells]

OBJECTIVE

To investigate the effect of calenduloside E on lipopolysaccharide (LPS)-induced inflammatory response in RAW264.7 cells and explore the underlying molecular mechanism.

METHODS

CCK-8 assay was used to examine the effect of different concentrations of calenduloside E (0-30 μg/mL) on the viability of RAW264.7 cells. The release of the pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in RAW264.7 cells in response to pretreatment with 6, 8, and 10 μg/mL calenduloside E for 2 h followed by stimulation with 100 ng/mL LPS was detected using enzyme-linked immunosorbent assay (ELISA). The expression levels of iNOS and COX-2 and the activation of JAK-stats, MAPKs and NF-кB signaling pathways in the treated cells were determined using Western blotting. A reactive oxygen species (ROS) detection kit was used to detect ROS production in the cells, and the nuclear translocation of the transcription factor stat3 was observed by laser confocal microscopy.

RESULTS

Calenduloside E below 20 μg/mL did not significantly affect the viability of RAW264.7 cells. Calenduloside E dose-dependently decreased the expression levels of iNOS and COX-2 induced by LPS, inhibited LPS-induced release of TNF-α and IL-1β, and suppressed LPS-induced JAK1-stat3 signaling pathway activation and stat3 nuclear translocation. Calenduloside E also significantly reduced ROS production induced by LPS in RAW264.7 cells.

CONCLUSIONS

Calenduloside E inhibits LPS-induced inflammatory response by blocking ROS-mediated activation of JAK1-stat3 signaling pathway in RAW264.7 cells.

Baicalein Inhibits Dextran Sulfate Sodium-induced Mouse Colitis

Background

Baicalein is a bioactive flavone that is originally extracted from the root of Scutellaria baicalensis Georgi. This plant has long served as Chinese herbal medicine in the management of multiple diseases including inflammatory bowel diseases. Although it has been revealed that baicalein inhibits experimental colitis in mice, the molecular mechanisms still remain largely unrecognized.

Methods

The experimental colitis was induced in mice by 3% dextran sulfate sodium (DSS) in drinking water. The mice were given baicalein (10 or 25 mg/kg) by gavage for 7 days before and after DSS administration. Expression of COX-2 and inducible nitric oxide synthase (iNOS) and molecules involved in NF-κB signaling, such as inhibitor of κBα (IκBα), pIκBα, p65, and phospho-p65 was examined by Western blot analysis in the tissue of the mouse colon. Activity of IκB kinase β (IKKβ) was assessed by measuring the relative amount of radioactive γ-phosphate of ATP transferred to the IκBα substrate protein. The expression and phosphorylation of STAT3 and its target gene cyclin D1 were also measured.

Results

Baicalein prominently mitigated the severity of DSS-induced colitis in mice. It inhibited the expression of COX-2 and iNOS. Moreover, baicalein attenuated activity and phosphorylation of IKKβ and subsequent degradation of IκBα. Baicalein suppressed the phosphorylation and nuclear translocation of p65, resulting in a reduced DNA binding activity of NF-κB. Baicalein also suppressed the phosphorylation of STAT3 and expression of cyclin D1. Baicalein exhibited the synergistic effect on inhibition of COX-2 induced by DSS with curcumin, an ingredient of turmeric.

Conclusions

Protective effects of baicalein on DSS-induced colitis are associated with suppression of NF-κB and STAT3 signaling pathways, which may contribute to its cancer preventive effects on colon carcinogenesis.

Identification of Chinese Herbal Compounds with Potential as JAK3 Inhibitors

The Janus kinases (JAKs) consist of four similar tyrosine kinases and function as key hubs in the signaling pathways that are implicated in both innate and adaptive immunity. Among the four members, JAK3 is probably the more attractive target for treatment of inflammatory diseases because its inhibition demonstrates the greatest immunosuppression and most profound effect in the treatment of such disorders. Although many JAK3 inhibitors are already available, certain shortcomings have been identified, mostly acquired drug resistance or unwanted side effects. To discover and identify new promising lead candidates, in this study, the structure of JAK3 (3LXK) was obtained from the Protein Data Bank and used for simulation modeling and protein-ligand interaction analysis. The ~36,000 Chinese herbal compounds obtained from TCM Database@Taiwan were virtually screened by AutoDock Vina docking program and filtered with Lipinski's Rules and ADME/T virtual predictions. Because of high occurrence of fake hits during docking, we selected 12 phytochemicals which have demonstrated modulating JAKs expressions among the top 50 chemicals from docking results. To validate whether these compounds are able to directly mediate JAK3 kinase, we have investigated the inhibitory activity using enzymatic activity assays, western blot, and HEK 293 cell STAT5 transactivity assays. The molecular analysis included docking and molecular dynamics (MD) simulations in order to investigate structural conformations and to explore the key amino acids in the interaction between JAK3 kinase and its putative ligands. The results demonstrated that Cryptotanshinone, Icaritin, and Indirubin exhibited substantial inhibitory activity against JAK3 kinase in vitro. The results also provide binding models of the protein-ligand interaction, detailing the interacting amino acid residues at the active ATP-binding domains of JAK3 kinase. In conclusion, our work discovered 3 potential natural inhibitors of JAK3 kinase and could provide new possibilities and stimulate new insights for the treatment of JAK3-targeted diseases.

Candida albicans cell wall mannoprotein synergizes with lipopolysaccharide to affect RAW264.7 proliferation, phagocytosis and apoptosis

With the widespread use of invasive surgery, immunosuppressive therapy and broad-spectrum antibiotics, there has resulted a corresponding increase in severe systemic infections as produced by Candida albicans (C.albicans), as it combines with bacterial infections. Such infections often result in high rates of mortality. In this report, we examined the effects of the C. albicans cell wall mannoprotein (MP) on macrophage immunity. The MTS assay was used to detect cell proliferation activity and neutral red staining to observe cell phagocytosis. The Griess method was used to detect NO secretion in culture supernatants and apoptosis of macrophages were determined with use of FITC-Annexin V and PI staining. mRNA and protein expressions of JAK2, STAT3, IL-1β, IL-6, TNF-α and iNOS in RAW264.7 cells were determined with use of RT-PCR and western blot. MP significantly promoted the proliferation of RAW264.7 cells, inhibited their phagocytic capacity, but exerted no significant effects on apoptosis of macrophages. In addition, MP not only up-regulated the expression of cytokines, but also the expressions of p-stat3 and p-jak2. Interestingly, when MP was combined with lipopolysaccharide (LPS) a markedly accentuated release of inflammatory cytokines was observed. MP promotes macrophage inflammation induced by LPS and participates in the inflammatory response. One of the potential mechanisms of this effect involves MP activation of the JAK2/STAT3 signaling pathway in RAW264.7 cells, which enables macrophages to transform from M0 to M1 and promote the occurrence of inflammation.

Hepatoprotective Effect of Baicalein Against Acetaminophen-Induced Acute Liver Injury in Mice

Baicalein (BAI), one of the main components of Scutellaria baicalensis Georgi, possesses numerous pharmacological properties, including anti-cancer, anti-oxidative, anti-virus and anti-bacterial activities. The purpose of this study was to evaluate the hepatoprotective effect of baicalein against acetaminophen (APAP)-exposed liver injury in mice, and elucidate the underlying hepatoprotective mechanism. Baicalein pretreatment significantly alleviated the elevation of IL-6, IL-1β and TNF-α in serum and hepatic in a dose-dependent manner. It also dose-dependently reduced the hepatic malondialdehyde (MDA) concentration, as well as the depletion of hepatic superoxide dismutase (SOD), hepatic glutathione (GSH) and hepatic catalase (CAT). Moreover, pretreatment with baicalein significantly ameliorated APAP-exposed liver damage and histological hepatocyte changes. Baicalein also relieved APAP-induced autophagy by regulating AKT/mTOR pathway, LC3B and P62 expression. Furthermore, the hepatoprotective effect of baicalein to APAP-induced liver injury involved in Jak2/Stat3 and MAPK signaling pathway. Taken together, our findings suggested that baicalein exhibits the ability to prevent liver from APAP-induced liver injury and provided an underlying molecular basis for potential applications of baicalein to cure liver injuries.

Redox-Sensitive Innate Immune Pathways During Macrophage Activation in Type 1 Diabetes

SIGNIFICANCE

Type 1 diabetes (T1D) is an autoimmune disease resulting in β-cell destruction mediated by islet-infiltrating leukocytes. The role of oxidative stress in human and murine models of T1D is highly significant as these noxious molecules contribute to diabetic complications and β-cell lysis, but their direct impact on dysregulated autoimmune responses is highly understudied. Pro-inflammatory macrophages play a vital role in the initiation and effector phases of T1D by producing free radicals and pro-inflammatory cytokines to facilitate β-cell destruction and to present antigen to autoreactive T cells. Recent Advances: Redox modulation of macrophage functions may play critical roles in autoimmunity. These include enhancing pro-inflammatory innate immune signaling pathways in response to environmental triggers, enforcing an M1 macrophage differentiation program, controlling antigen processing, and altering peptide recognition by oxidative post-translational modification. Therefore, an oxidative environment may act on multiple macrophage functions to orchestrate T1D pathogenesis.

CRITICAL ISSUES

Mechanisms involved in the initiation of T1D remain unclear, making preventive and early therapeutics difficult to develop. Although many of these advances in the redox regulation of macrophages are in their infancy, they provide insight into how oxidative stress aids in the precipitating event of autoimmune activation.

FUTURE DIRECTIONS

Future studies should be aimed at mechanistically determining which redox-regulated macrophage functions are pertinent in T1D pathogenesis, as well as at investigating potential targetable therapeutics to halt and/or dampen innate immune activation in T1D.

Aloin suppresses lipopolysaccharide‑induced inflammation by inhibiting JAK1‑STAT1/3 activation and ROS production in RAW264.7 cells

The anti-inflammatory effects of aloin, a bioactive ingredient extracted from Aloe vera, have been described previously. The present study aimed to assess these effects and explore the underlying molecular mechanisms. RAW264.7 cells were incubated with different doses of aloin (100, 150 and 200 µg/ml) and lipopolysaccharide (LPS; 100 ng/ml) for the indicated times. Then, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 expression levels were detected by western blot analysis and reverse transcription polymerase chain reaction (RT-PCR). The concentrations of inflammatory cytokines in the cell culture supernatant were determined by ELISA. Total nitric oxide (NO) assay and reactive oxygen species (ROS) kits were used to detect NO and ROS levels, respectively. Mitogen-activated protein kinase, nuclear factor κB and Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway activation were verified by western blot analysis. Confocal and nucleocytoplasmic separation experiments were used to detect STAT nuclear translocation. It was identified that aloin decreased the level of LPS-induced iNOS expression, inhibiting the release of interleukin (IL)-1β, IL-6, tumour necrosis factor-α and NO dose-dependently. Mechanistically, aloin suppressed LPS-induced JAK1-STAT1/3 activation and STAT1/3 nuclear translocation. Additionally, LPS-induced ROS production was inhibited by aloin. Collectively, these data suggest that aloin attenuated LPS-induced inflammation by inhibiting ROS-mediated activation of the JAK1-STAT1/3 signalling pathway, thereby inhibiting the nuclear translocation of STAT1/3 in RAW264.7 cells. The present study provides an experimental basis for the clinical application of aloin in inflammatory-associated diseases.

Semi-Mechanism-Based Pharmacodynamic Model for the Anti-Inflammatory Effect of Baicalein in LPS-Stimulated RAW264.7 Macrophages

Monitoring of the inhibition of TNF-α, IL-6, iNOS, and NO is used to effectively evaluate anti-inflammatory drugs. Baicalein was found to have good anti-inflammatory activities, but its detailed cellular pharmacodynamic events have not been expatiated by any other study. The inflammatory mediators, including TNF-α, IL-6, iNOS, and NO production in RAW264.7 macrophage induced by LPS, were measured. It was found that these data showed a sequential pattern on time and based on these points a cellular pharmacodynamic model was developed and tested. TNF-α and IL-6 were quantified by ELISA, NO was detected by Griess and iNOS expression was measured by Western blot. The pharmacodynamic model was developed using a NLME modeling program Monolix® 2016R1.¹The results showed that baicalein quickly suppressed release of TNF-α in a concentration-dependent manner, and consequently causing the diminution of IL-6 and iNOS/NO. The pharmacodynamic model simulation successfully described the experimental data, supporting the hypothesis that IL-6 and iNOS /NO release after LPS stimulation is mediated by TNF-α rather than LPS directly. The pharmacodynamic model allowed a well understanding of the cellular pharmacodynamic mechanism of baicalein in the treatment of inflammatory diseases.

Baicalein acts as a nephroprotectant that ameliorates colistin-induced nephrotoxicity by activating the antioxidant defence mechanism of the kidneys and down-regulating the inflammatory response

Background

Nephrotoxicity is the major adverse effect patients experience during colistin therapy. The development of effective nephroprotective agents that can be co-administered during polymyxin therapy remains a priority area in antimicrobial chemotherapy.

Objectives

To investigate the nephroprotective effect of baicalein, a component of the root of Scutellaria baicalensis, against colistin-induced nephrotoxicity using a mouse model.

Methods

C57BL/6 mice were randomly divided into the following groups: control, baicalein 100 mg/kg/day (administered orally), colistin (18 mg/kg/day administered intraperitoneally) and colistin (18 mg/kg/day) plus baicalein (25, 50 and 100 mg/kg/day). After 7 day treatments, histopathological damage, the markers of renal functions, oxidative stress and inflammation were examined. The expressions of Nrf2, HO-1 and NF-κB mRNAs were also further examined using quantitative RT-PCR examination.

Results

Baicalein co-administration markedly attenuated colistin-induced oxidative and nitrative stress, apoptosis, the infiltration of inflammatory cells, and caused decreases in IL-1β and TNF-α levels (all P < 0.05 or 0.01) in the kidney tissues. Baicalein co-administration up-regulated expression of Nrf2 and HO-1 mRNAs and down-regulated the expression of NF-κB mRNA, compared with those in the colistin alone group.

Conclusions

To the best of our knowledge, this is the first study demonstrating the protective effect of baicalein on colistin-induced nephrotoxicity and apoptosis by activating the antioxidant defence mechanism in kidneys and down-regulating the inflammatory response. Our study highlights that oral baicalein could potentially ameliorate nephrotoxicity in patients undergoing polymyxin therapy.

Inhibitory effect of baicalein combined with gemcitabine in human pancreatic cancer cell lines

Pancreatic cancer is an aggressive disease with a particularly poor prognosis contributing to a substantial percentage of cancer-associated mortality rates. In the present study, the combination treatment of baicalein (BAI) and gemcitabine (GEM) was investigated to examine whether it inhibited the growth of the human CFPAC-1 pancreatic cancer cell line in vitro and in vivo. The cytotoxic interactions between BAI and GEM in human pancreatic cancer cell lines were determined using MTT assays, and the effect of the two agents on apoptosis was detected using Hoechst 33258 staining and annexin V/7-AAD. The protein levels of Bcl-2-associated X protein (Bax), B-cell lymphoma 2 (Bcl-2), caspase-3, poly ADP ribose polymerase (PARP) and survivin were detected using western blot analysis. Furthermore, the expression levels of Bax, Bcl-2, caspase-3 and survivin in tumor tissues were detected using immunohistochemistry. The results demonstrated that following GEM treatment, the growth of CFPAC-1 cells and xenografts in nude mice were inhibited, and the expression levels of Bcl-2 and survivin were downregulated, whilst the expression levels of Bax, caspase-3 and PARP were upregulated. These effects were enhanced with the use of BAI in combination with GEM. The mechanism underlying the anti-tumor effect of BAI combined with GEM may be associated with the induction of cell apoptosis and the inhibition of proliferation. To the best of our knowledge, this is the first evidence of the efficacy of BAI against pancreatic cancer and may provide the potential clinical evidence for the use of this drug combination for the treatment of patients with pancreatic cancer.

Baicalein reduces angiogenesis in the inflammatory microenvironment via inhibiting the expression of AP-1

Increasing clinical and experimental studies have demonstrated that refractory chronic inflammation will result in malignant tumor and anti-angiogenic therapy may be an effective way to thwart the progression. Baicalein, one of the major active flavanoids found in Scutellaria baicalensis Georgi, has been exhibited potent anti-inflammation and anti-tumor effects by reducing angiogenesis. However, the exact mechanism of baicalein on endothelial cells in inflammatory microenvironment was not clear yet. Here, we investigated the anti-angiogenic effect of baicalein by incubating human umbilical vein endothelial cells (HUVECs) with THP-1 conditioned medium in vitro. The tube formation of HUVECs and microvessel outgrowth of rat aorta were attenuated, as well as the number of newly formed blood vessels in chicken chorioallantoic membrane (CAM) was reduced by baicalein. This anti-angiogenic effect was mainly on account of the inhibited motility, migration and invasion of HUVECs. In addition, mechanistic studies showed that baicalein could bind to AP-1 directly and the expression of c-Jun and c-Fos in HUVECs was reduced, accompanied by their increased proteasomal degradation. Besides, baicalein suppressed the nuclear translation, heterodimer formation and DNA binding affinity of c-Jun and c-Fos. What's more, the anti-angiogenic effect of baicalein was further confirmed by matrigel plug assay in vivo. Taken together, our study demonstrated that baicalein could exert its anti-angiogenic effect in the inflammation microenvironment via inhibiting the transcriptional activity of AP-1, which suggested that baicalein might be an alternative treatment against refractory chronic inflammation.

Falcarindiol inhibits LPS-induced inflammation via attenuating MAPK and JAK-STAT signaling pathways in murine macrophage RAW 264.7 cells

Falcarindiol (FAD) is a natural polyacetylene compound found rich in many plants of the Umbelliferae family. Previously, we isolated FAD from the rhizome of Cnidium officinale Makino, which belongs to the Umbelliferae family and found it to have a significant inhibitory effect on lipopolysaccharide (LPS)-induced production of nitric oxide, a pro-inflammatory molecule in murine macrophage RAW 264.7 cells. In this study, we investigated its effect on the expression of other major pro-inflammatory molecules as well as the mechanism underlying these effects. Pre-treatment of RAW 264.7 cells with FAD suppressed LPS-stimulated mRNA expression of inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNFα), interleukin-6 (IL-6), and interleukin-1 beta (IL-1β) and thereby reduced the respective protein levels. Mechanistic studies demonstrated that FAD attenuated the LPS-induced activation of JNK, ERK, STAT1, and STAT3 signaling molecules. Moreover, we found that FAD did not influence LPS-induced activation of p38 and NFκB signaling pathways. Collectively, this study provides evidence that FAD inhibits the production of major pro-inflammatory molecules in LPS-challenged murine macrophages via suppression of JNK, ERK, and STAT signaling pathways.