Design, synthesis, and anti-cancer evaluation of C-14 arylcarbamate derivatives of andrographolide.

In this study, we explored a concise and mild synthetic route to produce novel C-14 arylcarbamate derivatives of andrographolide, a known anti-inflammatory and anticancer natural product. Upon assessing their anti-cancer efficacy against pancreatic ductal adenocarcinoma (PDAC) cells, some derivatives showed stronger cytotoxicity against PANC-1 cells than andrographolide. In addition, we demonstrated one derivative, compound 3m, effectively reduced the expression of oncogenic p53 mutant proteins (p53R273H and p53R248W), proliferation, and migration in PDAC lines, PANC-1 and MIA PaCa-2. Accordingly, the novel derivative holds promise as an anti-cancer agent against pancreatic cancer. In summary, our study broadens the derivative library of andrographolide and develops an arylcarbamate derivative of andrographolide with promising anticancer activity against PDAC.

Galgravin Isolated from Piper kadsura Ameliorates Lipopolysaccharide (LPS)-Induced Endotoxemia in Mice.

Sepsis results from uncontrolled inflammation, characterized by cytokine storm and immunoparalysis. To assess whether galgravin, a natural lignan isolated from Piper kadsura, can be used to treat sepsis, models of bacterial lipopolysaccharide (LPS)-activated macrophages and LPS-induced endotoxemia mice were used. Galgravin suppressed NF-κB activation in LPS-activated RAW 264.7 macrophages without causing significant cytotoxicity, in which proinflammatory molecules like TNF-α, IL-6, iNOS, and COX-2 were downregulated. In addition, the expression of TNF-α and IL-6 was also suppressed by galgravin in LPS-activated murine bone marrow-derived macrophages. Moreover, galgravin significantly downregulated the mRNA expression of TNF-α, IL-6, and iNOS in the lungs and decreased TNF-α and IL-6 in the serum and IL-6 in the bronchoalveolar lavage fluid of LPS-challenged mice. The COX-2 expression in tissues, including the lung, liver, and kidney, as well as the lung alveolar hemorrhage, was also reduced by galgravin. The present study reveals the anti-inflammatory effects of galgravin in mouse models and implies its potential application in inflammation diseases.

Anti-Cancer and Anti-Inflammatory Activities of Three New Chromone Derivatives from the Marine-Derived Penicillium citrinum.

Three new and uncommon chromone analogs, epiremisporine F (1), epiremisporine G (2), and epiremisporine H (3), were isolated from marine-origin Penicillium citrinum. Among the isolated compounds, compounds 2-3 remarkably suppressed fMLP-induced superoxide anion generation by human neutrophils, with IC50 values of 31.68 ± 2.53, and 33.52 ± 0.42 µM, respectively. Compound 3 exhibited cytotoxic activities against human colon carcinoma (HT-29) and non-small lung cancer cell (A549) with IC50 values of 21.17 ± 4.89 and 31.43 ± 3.01 µM, respectively, and Western blot assay confirmed that compound 3 obviously induced apoptosis of HT-29 cells, via Bcl-2, Bax, and caspase 3 signaling cascades.

Rare Chromone Derivatives from the Marine-Derived Penicillium citrinum with Anti-Cancer and Anti-Inflammatory Activities.

Three new and rare chromone derivatives, epiremisporine C (1), epiremisporine D (2), and epiremisporine E (3), were isolated from marine-derived Penicillium citrinum, together with four known compounds, epiremisporine B (4), penicitrinone A (5), 8-hydroxy-1-methoxycarbonyl-6-methylxanthone (6), and isoconiochaetone C (7). Among the isolated compounds, compounds 2-5 significantly decreased fMLP-induced superoxide anion generation by human neutrophils, with IC50 values of 6.39 ± 0.40, 8.28 ± 0.29, 3.62 ± 0.61, and 2.67 ± 0.10 µM, respectively. Compounds 3 and 4 exhibited cytotoxic activities with IC50 values of 43.82 ± 6.33 and 32.29 ± 4.83 µM, respectively, against non-small lung cancer cell (A549), and Western blot assay confirmed that compounds 3 and 4 markedly induced apoptosis of A549 cells, through Bcl-2, Bax, and caspase 3 signaling cascades.

Arginine Methylation of hnRNPK Inhibits the DDX3-hnRNPK Interaction to Play an Anti-Apoptosis Role in Osteosarcoma Cells.

Heterogeneous nuclear ribonucleoprotein K (hnRNPK) is an RNA/DNA binding protein involved in diverse cell processes; it is also a p53 coregulator that initiates apoptosis under DNA damage conditions. However, the upregulation of hnRNPK is correlated with cancer transformation, progression, and migration, whereas the regulatory role of hnRNPK in cancer malignancy remains unclear. We previously showed that arginine methylation of hnRNPK attenuated the apoptosis of U2OS osteosarcoma cells under DNA damage conditions, whereas the replacement of endogenous hnRNPK with a methylation-defective mutant inversely enhanced apoptosis. The present study further revealed that an RNA helicase, DDX3, whose C-terminus preferentially binds to the unmethylated hnRNPK and could promote such apoptotic enhancement. Moreover, C-terminus-truncated DDX3 induced significantly less apoptosis than full-length DDX3. Notably, we also identified a small molecule that docks at the ATP-binding site of DDX3, promotes the DDX3-hnRNPK interaction, and induces further apoptosis. Overall, we have shown that the arginine methylation of hnRNPK suppresses the apoptosis of U2OS cells via interfering with DDX3-hnRNPK interaction. On the other hand, DDX3-hnRNPK interaction with a proapoptotic role may serve as a target for promoting apoptosis in osteosarcoma cells.

Perturbation of p38α MAPK as a Novel Strategy to Effectively Sensitize Chronic Myeloid Leukemia Cells to Therapeutic BCR-ABL Inhibitors.

Chronic myeloid leukemia (CML) is a hematopoietic malignancy characterized by the presence of the BCR-ABL oncogene. Therapeutic regimens with tyrosine kinase inhibitors (TKIs) specifically targeting BCR-ABL have greatly improved overall survival of CML. However, drug intolerance and related toxicity remain. Combined therapy is effective in reducing drug magnitude while increasing therapeutic efficacy and, thus, lowers undesired adverse side effects. The p38 MAPK activity is critically linked to the pathogenesis of a number of diseases including hematopoietic diseases; however, the role of each isozyme in CML and TKI-mediated effects is still elusive. In this study, we used specific gene knockdown to clearly demonstrate that the deficiency of p38α greatly enhanced the therapeutic efficacy in growth suppression and cytotoxicity of TKIs, first-generation imatinib, and second generation dasatinib by approximately 2.5-3.0-fold in BCR-ABL-positive CML-derived leukemia K562 and KMB5 cells. Knockdown of p38ß, which displays the most sequence similarity to p38α, exerted distinct and opposite effects on the TKI-mediated therapeutic efficacy. These results show the importance of isotype-specific intervention in enhancing the therapeutic efficacy of TKI. A highly specific p38α inhibitor, TAK715, also significantly enhanced the imatinib- and dasatinib-mediated therapeutic efficacy, supporting the feasibility of p38α deficiency in future clinic application. Taken together, our results demonstrated that p38α is a promising target for combined therapy with BCR-ABL-targeting tyrosine kinase inhibitors for future application to increase therapeutic efficacy.

Diterpenoid Compounds Isolated from Chloranthus oldhamii Solms Exert Anti-Inflammatory Effects by Inhibiting the IKK/NF-κB Pathway.

Chloranthus oldhamii Solms (CO) is a folk medicine for treating infection and arthritis pain but its pharmacological activity and bioactive compounds remain mostly uncharacterized. In this study, the anti-inflammatory compounds of C. oldhamii were identified using an LPS-stimulated, NF-κB-responsive RAW 264.7 macrophage reporter line. Three diterpenoid compounds, 3α-hydroxy-ent-abieta-8,11,13-triene (CO-9), 3α, 7ß-dihydroxy-ent-abieta-8,11,13-triene (CO-10), and decandrin B (CO-15) were found to inhibit NF-κB activity at nontoxic concentrations. Moreover, CO-9 and CO-10 suppressed the expression of IL-6 and TNF-α in LPS-stimulated RAW 264.7 cells. The inhibitory effect of CO-9 on TNF-α and IL-6 expression was further demonstrated using LPS-treated bone marrow-derived macrophages. Furthermore, CO-9, CO-10, and CO-15 suppressed LPS-triggered COX-2 expression and downstream PGE2 production in RAW 264.7 cells. CO-9 and CO-10 also reduced LPS-triggered iNOS expression and nitrogen oxide production in RAW 264.7 cells. The anti-inflammatory mechanism of the most effective compound, CO-9, was further investigated. CO-9 attenuated LPS-induced NF-κB activation by reducing the phosphorylation of IKKα/ß (Ser176/180), IκBα (Ser32), and p65 (Ser534). Conversely, CO-9 did not affect the LPS-induced activation of MAPK signaling pathways. In summary, this study revealed new anti-inflammatory diterpenoid compounds from C. oldhamii and demonstrated that the IKK-mediated NK-κB pathway is the major target of these compounds.

Andrographolide and its fluorescent derivative inhibit the main proteases of 2019-nCoV and SARS-CoV through covalent linkage.

The coronavirus disease 2019 (COVID-19) pandemic caused by 2019 novel coronavirus (2019-nCoV) has been a crisis of global health, whereas the effective vaccines against 2019-nCoV are still under development. Alternatively, utilization of old drugs or available medicine that can suppress the viral activity or replication may provide an urgent solution to suppress the rapid spread of 2019-nCoV. Andrographolide is a highly abundant natural product of the medicinal plant, Andrographis paniculata, which has been clinically used for inflammatory diseases and anti-viral therapy. We herein demonstrate that both andrographolide and its fluorescent derivative, the nitrobenzoxadiazole-conjugated andrographolide (Andro- NBD), suppressed the main protease (Mpro) activities of 2019-nCoV and severe acute respiratory syndrome coronavirus (SARS-CoV). Moreover, Andro-NBD was shown to covalently link its fluorescence to these proteases. Further mass spectrometry (MS) analysis suggests that andrographolide formed a covalent bond with the active site Cys145 of either 2019-nCoV Mpro or SARS-CoV Mpro. Consistently, molecular modeling analysis supported the docking of andrographolide within the catalytic pockets of both viral Mpros. Considering that andrographolide is used in clinical practice with acceptable safety and its diverse pharmacological activities that could be beneficial for attenuating COVID-19 symptoms, extensive investigation of andrographolide on the suppression of 2019-nCoV as well as its application in COVID-19 therapy is suggested.

Evaluation of Antioxidant and Anti-α-glucosidase Activities of Various Solvent Extracts and Major Bioactive Components from the Seeds of Myristica fragrans.

Myristica fragrans is a well-known species for flavoring many food products and for formulation of perfume and medicated balm. It is also used to treat indigestion, stomach ulcers, liver disorders, and, as emmenagogue, diaphoretic, diuretic, nervine, and aphrodisiac. We examined antioxidant properties and bioactive compounds in various solvent extracts from the seeds of M. fragrans. Methanol, ethanol, and acetone extracts exhibited relatively strong antioxidant activities by 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), superoxide radical, and hydroxyl radical scavenging tests. Furthermore, methanol extracts also displayed significant anti-α-glucosidase activity. Examined and compared to the various solvent extracts for their chemical compositions using HPLC analysis, we isolated the ten higher content compounds and analyzed antioxidant and anti-α-glucosidase activities. Among the isolates, dehydrodiisoeugenol, malabaricone B and malabaricone C were main antioxidant components in seeds of M. fragrans. Malabaricone C exhibited stronger antioxidant capacities than others based on lower half inhibitory concentration (IC50) values in DPPH and ABTS radical scavenging assays, and it also showed significant inhibition of α-glucosidase. These results shown that methanol was found to be the most efficient solvent for extracting the active components from the seeds of M. fragrans, and this material is a potential good source of natural antioxidant and α-glucosidase inhibitor.

2-(2-Phenylethyl)-4H-chromen-4-one Derivatives from the Resinous Wood of Aquilaria sinensis with Anti-Inflammatory Effects in LPS-Induced Macrophages.

The resinous wood of Aquilaria sinensis, known as agarwood (Chen Xiang in Chinese), is traditionally used for the treatment of abdominal pain, vomiting, circulatory disorders, and dyspnea. Four new 2-(2-phenylethyl)-4H-chromen-4-one derivatives, namely 7-methoxy-2-[2-(4'-hydroxy-phenyl)ethyl]chromone (1), 7-hydroxy-2-[2-(4'-methoxyphenyl)ethyl]chromone (2), 5,6-dihydroxy- 2-[2-(3'-hydroxy-4'-methoxyphenyl)ethyl]chromone (3), and 6-hydroxy-5-methoxy-2-(2-phenyl-ethyl)chromone (4), have been isolated from the resinous wood of A. sinensis, together with nine known compounds. The structures of these compounds were determined through spectroscopic and MS analyses. Among the isolated compounds, neopetasan, 7-methoxy-2-(2-phenylethyl)-chromone, 6,7-dimethoxy-2-(2-phenylethyl)chromone, and 6,7-dimethoxy-2-[2-(4'-methoxy-phenyl)ethyl]chromone inhibited NF-κB activation in LPS-stimulated RAW 264.7 macrophages with relative luciferase activity values of 0.55 ± 0.09, 0.54 ± 0.03, 0.31 ± 0.05, and 0.38 ± 0.14, respectively, versus that of vehicle control (1.03 ± 0.02). In addition, 5,6-dihydroxy-2-[2-(3'-hydroxy-4'-methoxyphenyl)ethyl]chromone, 7-methoxy-2-(2-phenylethyl)chromone, 7-dimethoxy-2-(2-phenylethyl)chromone, and 6,7-dimethoxy-2-[2-(4'-methoxyphenyl)ethyl]chromone could suppress LPS-induced NO production in RAW 264.7 cells and did not induce cytotoxicity against RAW 264.7 cells after 24-h treatment.

Pilloin, A Flavonoid Isolated from Aquilaria sinensis, Exhibits Anti-Inflammatory Activity In Vitro and In Vivo.

Flavonoids, widely present in medicinal plants and fruits, are known to exhibit multiple pharmacological activities. In this study, we isolated a flavonoid compound, pilloin, from Aquilaria sinensis and investigated its anti-inflammatory activity in bacterial lipopolysaccharide-induced RAW 264.7 macrophages and septic mice. Pilloin inhibited NF-κB activation and reduced the phosphorylation of IκB in LPS-stimulated macrophages. Moreover, pilloin significantly suppressed the production of pro-inflammatory molecules, such as TNF-α, IL-6, COX-2 and iNOS, in LPS-treated RAW 264.7 macrophages. Additionally, pilloin suppressed LPS-induced morphological alterations, phagocytic activity and ROS elevation in RAW 264.7 macrophages. The mitogen-activated protein kinase-mediated signalling pathways (including JNK, ERK, p38) were also inhibited by pilloin. Furthermore, pilloin reduced serum levels of TNF-α (from 123.3 ± 7 to 46.6 ± 5.4 ng/mL) and IL-6 levels (from 1.4 ± 0.1 to 0.7 ± 0.1 ng/mL) in multiple organs of LPS-induced septic mice (liver: from 71.8 ± 3.2 to 36.7 ± 4.3; lung: from 118.6 ± 10.6 to 75.8 ± 11.9; spleen: from 185.9 ± 23.4 to 109.6 ± 18.4; kidney: from 160.3 ± 11.8 to 75 ± 10.8 pg/mL). In summary, our results demonstrate the anti-inflammatory potential of pilloin and reveal its underlying molecular mechanism of action.

Acylphloroglucinol Derivatives from Garcinia multiflora with Anti-Inflammatory Effect in LPS-Induced RAW264.7 Macrophages.

Two new acylphloroglucinol derivatives, 13,14-didehydroxygarcicowin C (1) and 13,14-didehydroxyisoxanthochymol (2), have been isolated from the stems of Garcinia multiflora, together with seven known compounds (3⁻9). The structures of new compounds 1 and 2 were elucidated by MS and extensive 1D/2D NMR spectroscopic analyses. Among the isolates, 13,14-didehydroxy-isoxanthochymol (2) and sampsonione B (3) exhibited inhibition against lipopolysaccharide (LPS)-induced NF-κB activation in macrophages at 30 µM with relative luciferase activity values (inhibitory %) of 0.75 ± 0.03 (24 ± 4%) and 0.12 ± 0.03 (88 ± 4%), respectively. Additionally, sampsonione B (3) reduced LPS-induced nitric oxide (NO) production in murine RAW264.7 macrophages and did not induce cytotoxicity against RAW 264.7 cells after 24 h treatment. Compound 3 is worth further investigation and may be expectantly developed as an anti-inflammatory drug candidate.

Arginine methylation of hnRNPK negatively modulates apoptosis upon DNA damage through local regulation of phosphorylation.

Heterogeneous nuclear ribonucleoprotein K (hnRNPK) is an RNA/DNA-binding protein involved in chromatin remodeling, RNA processing and the DNA damage response. In addition, increased hnRNPK expression has been associated with tumor development and progression. A variety of post-translational modifications of hnRNPK have been identified and shown to regulate hnRNPK function, including phosphorylation, ubiquitination, sumoylation and methylation. However, the functional significance of hnRNPK arginine methylation remains unclear. In the present study, we demonstrated that the methylation of two essential arginines, Arg296 and Arg299, on hnRNPK inhibited a nearby Ser302 phosphorylation that was mediated through the pro-apoptotic kinase PKCδ. Notably, the engineered U2OS cells carrying an Arg296/Arg299 methylation-defective hnRNPK mutant exhibited increased apoptosis upon DNA damage. While such elevated apoptosis can be diminished through addition with wild-type hnRNPK, we further demonstrated that this increased apoptosis occurred through both intrinsic and extrinsic pathways and was p53 independent, at least in part. Here, we provide the first evidence that the arginine methylation of hnRNPK negatively regulates cell apoptosis through PKCδ-mediated signaling during DNA damage, which is essential for the anti-apoptotic role of hnRNPK in apoptosis and the evasion of apoptosis in cancer cells.

Osthole ameliorates hepatic fibrosis and inhibits hepatic stellate cell activation.

BACKGROUND: Hepatic fibrosis is a dynamic process which ultimately leads to cirrhosis in almost patients with chronic hepatic injury. However, progressive fibrosis is a reversible scarring response. Activation of hepatic stellate cells (HSCs) is the prevailing process during hepatic fibrosis. Osthole is an active component majorly contained in the fruit of Cnidium monnieri (L.) Cusson. This present study investigated the therapeutic effects of osthole on rat liver fibrosis and HSC activation. RESULTS: We established the thioacetamide (TAA)-model of Sprague-Dawley (SD) rats to induce hepatic fibrosis. Rats were divided into three groups: control, TAA, and TAA + osthole (10 mg/kg). In vivo, osthole significantly reduced liver injury by diminishing levels of plasma AST and ALT, improving histological architecture, decreasing collagen and α-SMA accumulation, and improving hepatic fibrosis scores. Additionally, osthole reduced the expression of fibrosis-related genes significantly. Osthole also suppressed the production of fibrosis-related cytokines and chemokines. Moreover, nuclear translocation of p65 was significantly suppressed in osthole-treated liver. Osthole also ameliorated TAA-induced injury through reducing cellular oxidation. Osthole showed inhibitory effects in inflammation-related genes and chemokines production as well. In vitro, we assessed osthole effects in activated HSCs (HSC-T6 and LX-2). Osthole attenuated TGF-ß1-induced migration and invasion in HSCs. Furthermore, osthole decreased TNF-α-triggered NF-κB activities significantly. Besides, osthole alleviated TGF-ß1- or ET-1-induced HSCs contractility. CONCLUSIONS: Our study demonstrated that osthole improved TAA-caused liver injury, fibrogenesis and inflammation in rats. In addition, osthole suppressed HSCs activation in vitro significantly.

A novel TLR2-triggered signalling crosstalk synergistically intensifies TNF-mediated IL-6 induction.

Toll-like receptors (TLR) recognize pathogens and trigger the production of vigorous pro-inflammatory cytokines [such as tumour necrosis factor (TNF)] that induce systemic damages associated with sepsis and chronic inflammation. Cooperation between signals of TLR and TNF receptor has been demonstrated through the participation of TNF receptor 1 (TNFR) adaptors in endotoxin tolerance. Here, we identify a TLR2-mediated synergy, through a MyD88-independent crosstalk, which enhances subsequent TNF-mediated nuclear factor-kappa B activation and interleukin-6 induction. Membrane-associated adaptor MAL conduces the link between TNF receptor-associated factor 6 (TRAF6) and TNFR-associated death domain, leading to a distinctive K63-ubiquitinylated TRAF6 recruitment into TNFR complex. In summary, our results reveal a novel route of TLR signal that synergistically amplifies TNF-mediated responses, indicating an innovative target for inflammation manipulation.

A novel Aurora-A-mediated phosphorylation of p53 inhibits its interaction with MDM2.

PURPOSE: Crosstalk between Aurora-A kinase and p53 has been proposed. While the genetic amplification of Aurora-A has been observed in many human cancers, how p53 is regulated by Aurora-A remains ambiguous. In this study, Aurora-A-mediated phosphorylation of p53 was analyzed by mass spectrometry in order to identify a new phosphorylation site. Subsequently, the functional consequences of such phosphorylation were examined. EXPERIMENTAL DESIGN: In vitro phosphorylation of p53 by Aurora-A was performed and the phosphorylated protein was then digested with trypsin and enriched for phosphopeptides by immobilized metal affinity chromatography. Subsequently, a combination of ß-elimination and Michael addition was applied to the phosphopeptides in order to facilitate the identification of phosphorylation sites by MS. The functional consequences of the novel phosphorylation of p53 on the protein-protein interactions, protein stability and transactivation activity were then examined using co-immunoprecipitation, Western blotting and reporter assays. RESULTS: Ser-106 of p53 was identified as a novel site phosphorylated by Aurora-A. A serine-to-alanine mutation at this site was found to attenuate Aurora-A-mediated phosphorylation in vitro. In addition, phosphate-sensitive Phos-tag SDS-PAGE was used to confirm that the Ser-106 of p53 is in vivo phosphorylated by Aurora-A. Finally, co-immunoprecipitation studies suggested that Ser-106 phosphorylation of p53 decreases its interaction with MDM2 and prolongs the half-life of p53. CONCLUSIONS: The inhibition of the interaction between p53 and MDM2 by a novel Aurora-A-mediated p53 phosphorylation was identified in this study and this provides important information for further investigations into the interaction between p53 and Aurora-A in terms of cancer biology.

Effects of Kuan-Sin-Yin decoction on immunomodulation and tumorigenesis in mouse tumor models.

BACKGROUND: Complementary therapies are widely used among cancer patients. Kuan-Sin-Yin (KSY) decoction, a popular qi-promoting herbal medicine, was constituted with several herbs known to exhibit immunomodulating or anticancer activity. After combining these herbs as a compound formula, it is necessary to reassess the immunomodulation effects, the effects on tumor growth, and possible toxicity of KSY. METHODS: The anti-cancer effects of KSY in vivo were determined by measuring the tumor volumes, anticancer-associated cytokines (IFN-gamma, TNF-alpha, IL-2, and IL-12), accumulation of tumor infiltrating leukocytes (TILs), proliferation and apoptosis-related molecular markers (Ki-67, p53, p21, activated caspase 3, and cleaved PARP), and an in situ TUNEL assay. The body weight and serum chemistry of treated mice were also assessed. In vitro, the effects of KSY were evaluated using MTT assay, BrdU incorporation assay and cell growth curve. RESULTS: In vivo, KSY suppressed bladder or lung cancer growth but did not promote the production of cytokines nor increase the accumulation of TILs. The expression of p53 and p21 in KSY-treated mice were increased. The numbers of apoptotic tumor cells and the expression of apoptosis marker proteins (Caspase 3 and cleaved PARP) were not significantly elevated after KSY treatment. In vitro, the viability and proliferation of tumor cells, but not normal cells, were suppressed by KSY treatment. No significant toxicity was found in KSY-treated mice. CONCLUSIONS: KSY suppressed the tumor growth in vivo and in vitro, which resulted from its cytostatic effects on cancer cells, rather than the induction of anti-cancer immunity. Under these experimental conditions, no apparent toxicity was observed.

Hypericum sampsonii exhibits anti-inflammatory activity in a lipopolysaccharide-induced sepsis mouse model.

Background and aim: Sepsis causes an uncontrolled systemic response characterized by excessive inflammation and immune suppression, leading to multiple organ failure and death. An effective therapeutic strategy for sepsis-related syndromes is urgently needed. Hypericum sampsonii Hance (HS) is a folk herbal plant used to treat arthritis and dermatitis, but the anti-inflammatory properties of HS and its related compounds have rarely been investigated. In this study, we aimed to explore the anti-inflammatory effects of HS. Experimental procedure: Models of bacterial lipopolysaccharide (LPS)-induced activated macrophages and endotoxemia mice were used, in which the TLR4/NF-κB signaling pathway is upregulated to trigger inflammatory responses. The HS extract (HSE) was delivered into LPS-induced endotoxemia mice via oral administration. Three compounds were purified using column chromatography and preparative thin layer chromatography and were validated by physical and spectroscopic data. Results: HSE suppressed NF-κB activation and proinflammatory molecules (TNF-α, IL-6, iNOS) in LPS-activated RAW 264.7 macrophages. Furthermore, oral administration of HSE (200 mg/kg) to LPS-treated mice improved the survival rate, restored body temperature, decreased TNF-α and IL-6 in serum, and reduced IL-6 expression in bronchoalveolar lavage fluid (BALF). In lung tissues, HSE reduced LPS-induced leukocyte infiltration and the expression of proinflammatory molecules (TNF-α, IL-6, iNOS, CCL4 and CCL5). Three pure compounds isolated from HSE, including 2,4,6-trihydroxybenzophenone-4-O-geranyl ether, 1-hydroxy-7 methoxyxanthone and euxanthone, were demonstrated to exhibit anti-inflammatory activities in LPS-stimulated RAW 264.7 macrophages. Conclusion: The present study demonstrated the anti-inflammatory effects of HS in vitro and in vivo. Further clinical studies of HS in human sepsis are warranted.

Corrigendum: The traditional Chinese medicine formula Jing Guan Fang for preventing SARS-CoV-2 infection: from clinical observation to basic research.

[This corrects the article DOI: 10.3389/fphar.2022.744439.].

In vitro and in vivo anticancer activity of a synthetic glycolipid as Toll-like receptor 4 (TLR4) activator.

Activation of Toll-like receptor 4 (TLR4) triggers the innate immune response and leads to the induction of adaptive immunity. TLR4 agonists are known to function as immunostimulants and exhibit promising therapeutic potential for cancer immunotherapy. We have previously developed a synthetic serine-based glycolipid (designated as CCL-34) that can activate TLR4-dependent signaling pathways. In this study, the anticancer immunity of CCL-34 was further demonstrated. CCL-34-activated macrophages induced cancer cell death via the apoptotic pathway, and this cytotoxicity was significantly inhibited by NG-monomethyl-L-arginine (an inducible NOS inhibitor). Notably, conditioned medium collected from CCL-34-treated splenocytes also induced cytotoxicity toward cancer cells. Furthermore, CCL-34 treatment suppressed tumor growth and increased the survival rate in TLR4-functional C3H/HeN mice but not in TLR4-defective C3H/HeJ mice. Increased apoptosis, the induction of cytokines (IFN-γ and IL-12) and chemokines (CXCL9 and CXCL10), and the elevation of leukocyte markers (CD11b, CD11c, CD4, and CD8) were detected at tumor sites in C3H/HeN mice but not in C3H/HeJ mice. Structure-and-activity relationship analysis of CCL-34 and its structural analogs revealed that a sugar moiety is essential for its activity. However, the substitution of the galactose in CCL-34 with glucose or fucose did not reduce its activity. Altogether, this study reveals the anticancer activity of a new synthetic TLR4 agonist and broadens the molecular basis of TLR4-activating glycolipids.