Anti-inflammatory effect of procyanidin B1 on LPS-treated THP1 cells via interaction with the TLR4-MD-2 heterodimer and p38 MAPK and NF-κB signaling

Assessment on malvidin-3-glucoside interaction with TLR4 via multi-spectroscopic analysis and molecular docking

As one innate immune pattern recognition receptor, Toll-like receptor 4 (TLR4) recently has been considered as a critical player in glucolipid metabolism. Blueberries contain high level of anthocyanins, especially malvidin-3-glucoside (Mv-3-glc), which contribute the anti-inflammatory, hypoglycemic, and hypolipidemic effects. It is speculated that Mv-3-glc is able to possess these functions by binding to TLR4. Here, the noncovalent interactions of Mv-3-glc and TLR4 was explored through multi-techniques including fluorescence and ultraviolet-visible (UV-Vis) absorption spectroscopy, as well as molecular docking. The results demonstrated that Mv-3-glc was able to quench TLR4 intrinsic fluorescence effectively. A stable complex was formed spontaneously and the reaction was exothermic. The degree of binding of Mv-3-glc to TLR4 showed a strong dependence on the chemical concentration, temperature, and pH values. The negative signs for enthalpy (ΔH = -69.1 ± 10.8 kJ/mol) and entropy (ΔS = -105.0 ± 12.3 J/mol/K) from the interaction of the Mv-3-glc and TLR4 shows that the major driving forces are the hydrogen bonding and van der Waals' force, which is consistent with the molecular docking results. In addition, molecular docking predicted that the active center with specific amino acid residues, Phe126, Ser127, Leu54, Ile153, and Tyr131 was responsible for the site of Mv-3-glc binding to TLR4/myeloid differentiation protein-2 (MD-2). These findings confirmed that Mv-3-glc could bind to TLR4, which would be beneficial to understand the target therapeutic effects of blueberry anthocyanins on TLR4 in regulating glucolipid metabolism.

Exploring the potential of Ziziphus nummularia and luteolin-7-O-glucoside as tubulin inhibitors in cancer therapy and survival

Cancer is responsible for approximately 10 million deaths worldwide, with 70% of the deaths occurring in low- and middle-income countries; as such safer and more effective anti-cancer drugs are required. Therefore, the potential benefits of Ziziphus nummularia and Ziziphus spina-christi as sources of anti-cancer agents were investigated. Z. nummularia and Z. spina-christi extracts were prepared using chloroform, ethanol, ethyl acetate, and water. The extracts' anti-cancer properties were determined using the MTT Cell Viability Assay in four cancer cell lines: breast (KAIMRC2 and MDA-MB-231), colorectal (HCT8), and liver (HepG2). The ApoTox-Glo Triplex Assay and high-content imaging (HCI)-Apoptosis Assay were used to assess KAIMRC2 and HCT8 cells further. In addition, KAIMRC2 cells were tested for microtubule staining, and AKT/mTOR protein expression was determined by western blot analysis. Liquid chromatography-mass spectrometry (LC-MS) was performed to identify the secondary metabolites in the ethanol and ethyl acetate extracts, followed by in silico techniques to predict molecular targets and interactions, safety, and pharmacokinetic profile for identified metabolites. Out of the eight extracts, the ethanolic extract of Z. nummularia, exhibited the most potent activity against KAIMRC2 cells with an IC50 value of 29.2 μg/ml. Cancer cell treatment with the ethanolic extract of Z. nummularia resulted in a dose-dependent decrease in cell viability with increased apoptosis and cytotoxic effects. Microtubule staining showed a disrupted microtubular network. The ethanolic extract treatment of KAIMRC2 cells led to upregulated expression of pAKT and pmTOR. In silico studies predicted luteolin-7-O-glucoside to be a ligand for tubulin with the highest docking score (- 7.686) and similar binding interactions relative to the native ligand. Further computational analysis of the metabolites showed acceptable pharmacokinetic and safety profiles, although ethanolic extract metabolites were predicted to have cardiotoxic effects. Ethanolic extraction is optimal for solubilizing active anticancer metabolites from Z. nummularia, which may act by causing M-phase arrest via inhibition of tubulin polymerization. Luteolin-7-O-glucoside is the lead candidate for further research and development as an anti-cancer agent. In addition, this study suggests that herbal treatment could switch on mechanisms of adaptation and survival in cancer cells.

Tetrastigma hemsleyanum suppresses neuroinflammation in febrile seizures rats via regulating PKC-δ/caspase-1 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Tetrastigma hemsleyanum Diels et Gilg (T. hemsleyanum, Sanyeqing) has been used in the prevention and treatment of repetitive Febrile seizures (FS) over the centuries in China.

AIM OF THE STUDY

T. hemsleyanum exerts wide pharmacological action, which has been widely used for treating various diseases, including infantile febrile seizure. However, the systematic study on this herb's material basis and the functional mechanism is lacking. This study intended to systematically elucidate the mechanism of T. hemsleyanum against febrile seizures.

MATERIALS AND METHODS

The efficacy of T. hemsleyanum was estimated by using a hot bath as a model of FS, the onset and duration of seizure, morphological structure changes of hippocampal neurons as well as magnetoencephalography were applied to evaluate the effects. Meanwhile, the bioactive components of T. hemsleyanum responsible for the therapeutic effect of T. hemsleyanum on FS were identified by UPLC-MS/MS. Then we systematically elucidated the mechanism of T. hemsleyanum based on metabonomics, transcriptomics, network pharmacological and experimental validation.

RESULTS

In a hyperthermia-induced FS model of rats, T. hemsleyanum significantly increased the seizure latency and decreased seizure duration, alleviating the abnormal delta and gamma band activity during epileptic discharge. Furthermore, ten chemical components of ethanol extracts from T. hemsleyanum were identified by UPLC-MS/MS, including quercetin, kaempferol, and procyanidin B1 and so on, which was consistent with the network pharmacology prediction. The serum metabolomics indicated that T. hemsleyanum mainly acts on inflammation regulation and neuroprotection by the glycerophospholipid metabolism pathway. Ninety-two potential targets of T. hemsleyanum on FS were identified by network pharmacology, and TNF, IL-6, and IL-1β were considered the pivotal targets. In the hippocampus transcriptomics, 17 KEGG pathways were identified after T. hemsleyanum treatment compared with the FS model group, among which 15 pathways overlapped with those identified by network pharmacology, and the PKC-δ/caspase-1 signaling pathway was a critical node. Finally, in vivo experiments also verified T. hemsleyanum inhibited the activation of microglia and resulted in a significant reduction in the level of PKCδ, NLRC4, caspase-1, IL-1β, IL-6 and TNF-α in hippocampus of FS rats.

CONCLUSIONS

Our study suggested that the therapeutic effect of T. hemsleyanum on FS might be regulated by inhibiting the neuroinflammation, thus exerting an anticonvulsant effect in vivo, and the mechanism might be related to regulating the PKC-δ/caspase-1 signaling pathway.

Comparative analysis of flavonoid metabolites from different parts of Hemerocallis citrina

BACKGROUND

Hemerocallis citrina Baroni is a traditional medical and edible plant. It is rich in flavonoid compounds, which are a kind of important bioactive components with various health benefits and pharmaceutical value. However, the flavonoid metabolomics profile and the comparison of flavonoid compounds from different parts of H. citrina is scarce.

RESULTS

In this study, flavonoid metabolites were investigated from roots, stems, leaves and flowers of H. citrina. A total of 364 flavonoid metabolites were identified by UPLC-MS/MS based widely targeted metabolomics, and the four plant parts showed huge differences at flavonoid metabolic level. Compared to roots, 185, 234, and 119 metabolites accounted for upregulated differential flavonoid metabolites (DFMs) in stems, leaves, and flowers, respectively. Compared to stems, 168 and 29 flavonoid metabolites accounted for upregulated DFMs in leaves and flowers, respectively. Compared to leaves, only 29 flavonoid metabolites accounted for upregulated DFMs in flowers. A number of 35 common flavonoid metabolites were observed among six comparison groups, and each comparison group had its unique differential metabolites. The most abundant flavonoid metabolites in the four parts are flavonols and flavones, followed by flavanones, chalcones, flavanols, flavanonols, anthocyanidins, tannin, and proanthocyanidins. 6,7,8-Tetrahydroxy-5-methoxyflavone, 7,8,3',4'-tetrahydroxyflavone, 1-Hydroxy-2,3,8-trimethoxyxanthone, Farrerol-7-O-glucoside, 3',7-dihydroxy-4'-methoxyflavone, 3,3'-O-Dimethylellagic Acid, 5-Hydroxy-6,7-dimethoxyflavone, Nepetin (5,7,3',4'-Tetrahydroxy-6-methoxyflavone), (2s)-4,8,10-trihydroxy-2-methoxy-1 h,2 h-furo[3,2-a]xanthen-11-one are dominant in roots. Isorhamnetin-3-O-(6''-malonyl)glucoside-7-O-rhamnoside, 7-Benzyloxy-5-hydroxy-3',4'-methylenedioxyflavonoid, 3-Hydroxyphloretin-4'-O-glucoside are dominant in stems. Chrysoeriol-7-O-glucoside, Epicatechin glucoside, Kaempferol-3-O-rhamnoside (Afzelin)(Kaempferin)*, Azaleatin (5-O-Methylquercetin), Chrysoeriol-5-O-glucoside, Nepetin-7-O-glucoside(Nepitrin), 3,5,7,2'-Tetrahydroxyflavone; Datiscetin, Procyanidin B2*, Procyanidin B3*, Procyanidin B1, Isorhamnetin-3-O-(6''-acetylglucoside) are dominant in leaves. kaempferol-3-p-coumaroyldiglucoside, Delphinidin-3-O-sophoroside-5-O-glucoside, Limocitrin-3-O-sophoroside, Kaempferol-3-O-rutinoside(Nicotiflorin), Luteolin-7-O-(6''-malonyl)glucoside-5-O-rhamnoside are dominant in flowers.

CONCLUSION

There was significant difference in flavonoid metabolites among different parts of H. citrina. Leaves had relative higher metabolites contents than other parts. This study provided biological and chemical evidence for the different uses of various plant parts of H. citrina, and these informations are important theoretical basis for the food industry, and medical treatment.

The perception and influencing factors of astringency, and health-promoting effects associated with phytochemicals: A comprehensive review

Astringency as the complex sensory of drying or shrinking can be perceived from natural foods, including abundant phenolic compounds. Up to now, there have been two possible astringency perception mechanisms of phenolic compounds. The first possible mechanism involved chemosensors and mechanosensors and took salivary binding proteins as the premise. Although piecemeal reports about chemosensors, friction mechanosensor's perception mechanisms were absent. There might be another perception way because a part of astringent phenolic compounds also triggered astringency although they could not bind with salivary proteins, however, the specific mechanism was unclear. Structures caused the differences in astringency perception mechanisms and intensities. Except for structures, other influencing factors also changed astringency perception intensity and aimed to decrease it, which probably ignored the health-promoting effects of phenolic compounds. Therefore, we roundly summarized the chemosensor's perception processes of the first mechanism. Meanwhile, we speculated that friction mechanosensor's probably activated Piezo2 ion channel on cell membranes. Phenolic compounds directly binds with oral epithelial cells, activating Piezo2 ion channel probably the another astringency perception mechanism. Except for structure, the increase of pH values, ethanol concentrations, and viscosity not only lowered astringency perception but were beneficial to improve the bioaccessibility and bioavailability of astringent phenolic compounds, which contributed to stronger antioxidant, anti-inflammatory, antiaging and anticancer effects.

Proanthocyanins and anthocyanins in chestnut (Castanea mollissima) shell extracts: biotransformation in the simulated gastrointestinal model and interaction with gut microbiota in vitro

BACKGROUND

Chestnut (Castanea mollissima) shell is rich in flavonoids and our previous studies showed that proanthocyanins and anthocyanins were the two markedly varied flavonoids in chestnut shell extracts (CSE) during digestion. Here, the biotransformation of proanthocyanins and anthocyanins in a simulated gastrointestinal model, and the interactions between non-absorption CSE (NACSE) and gut microbiota in vitro, were investigated by ultra-high-performance liquid chromatography combined with triple-quadrupole mass spectrometry and 16S rRNA sequencing.

RESULTS

Chestnut shell was richer in proanthocyanins and anthocyanins, while the loss of proanthocyanins was greater after digestion. Additionally, the content of anthocyanin decreased after gastric digestion but increased after intestinal digestion and remained stable after fermentation. After fermentation, delphinidin-3-O-sambubioside and pelargonidin-3-O-galactoside were newly formed. Furthermore, microbiome profiling indicated that NACSE promoted the proliferation of beneficial bacteria, while inhibiting pathogenic bacteria.

CONCLUSION

All these data suggest that CSE may be a promising candidate to protect gut health. © 2023 Society of Chemical Industry.

Gut microbial metabolite hyodeoxycholic acid targets the TLR4/MD2 complex to attenuate inflammation and protect against sepsis

Sepsis, a critical condition resulting from the systemic inflammatory response to a severe microbial infection, represents a global public health challenge. However, effective treatment or intervention to prevent and combat sepsis is still lacking. Here, we report that hyodeoxycholic acid (HDCA) has excellent anti-inflammatory properties in sepsis. We discovered that the plasma concentration of HDCA was remarkably lower in patients with sepsis and negatively correlated with the severity of the disease. Similar changes in HDCA levels in plasma and cecal content samples were observed in a mouse model of sepsis, and these changes were associated with a reduced abundance of HDCA-producing strains. Interestingly, HDCA administration significantly decreased systemic inflammatory responses, prevented organ injury, and prolonged the survival of septic mice. We demonstrated that HDCA suppressed excessive activation of inflammatory macrophages by competitively blocking lipopolysaccharide binding to the Toll-like receptor 4 (TLR4) and myeloid differentiation factor 2 receptor complex, a unique mechanism that characterizes HDCA as an endogenous inhibitor of inflammatory signaling. Additionally, we verified these findings in TLR4 knockout mice. Our study highlights the potential value of HDCA as a therapeutic molecule for sepsis.

Proanthocyanidins: Impact on Gut Microbiota and Intestinal Action Mechanisms in the Prevention and Treatment of Metabolic Syndrome

The metabolic syndrome (MS) is a cluster of risk factors, such as central obesity, hyperglycemia, dyslipidemia, and arterial hypertension, which increase the probability of causing premature mortality. The consumption of high-fat diets (HFD) is a major driver of the rising incidence of MS. In fact, the altered interplay between HFD, microbiome, and the intestinal barrier is being considered as a possible origin of MS. Consumption of proanthocyanidins (PAs) has a beneficial effect against the metabolic disturbances in MS. However, there are no conclusive results in the literature about the efficacy of PAs in improving MS. This review allows a comprehensive validation of the diverse effects of the PAs on the intestinal dysfunction in HFD-induced MS, differentiating between preventive and therapeutic actions. Special emphasis is placed on the impact of PAs on the gut microbiota, providing a system to facilitate comparison between the studies. PAs can modulate the microbiome toward a healthy profile and strength barrier integrity. Nevertheless, to date, published clinical trials to verify preclinical findings are scarce. Finally, the preventive consumption of PAs in MS-associated dysbiosis and intestinal dysfunction induced by HFD seems more successful than the treatment strategy.

3',4'-Dihydroxyflavone mitigates inflammatory responses by inhibiting LPS and TLR4/MD2 interaction

BACKGROUND

We previously reported the potential inhibitory activity of 3',4'-dihydroxyflavone (DHF) on nitric oxide (NO) and prostaglandin E₂ (PGE₂) production in lipopolysaccharide (LPS)-stimulated macrophages.

PURPOSE

We investigated the underlying molecular mechanisms of DHF in LPS-activated macrophages and evaluated its effect on LPS-induced septic shock in mice.

METHODS

To explore the anti-inflammatory effect of DHF, nitrite, PGE₂, and cytokines were measured in vitro and in vivo experiments. In addition, to verify the molecular signaling pathway, quantitative real time-PCR, luciferase assay, nuclear extraction, electrophoretic mobility shift assay, immunocytochemistry, immunoprecipitation, molecular docking analysis, and myeloid differentiation 2 (MD2)-LPS binding assay were conducted.

RESULTS

DHF suppressed the LPS-induced expression of proinflammatory mediators through nuclear factor-κB (NF-κB), activator protein-1 (AP-1), and interferon regulatory factor 3 (IRF3) inactivation pathways in RAW 264.7 macrophages. Importantly, molecular docking analysis and in vitro binding assays showed that DHF interacts with the hydrophobic pocket of MD2 and then interferes with the interaction between LPS and toll-like receptor 4 (TLR4). DHF inhibited LPS-induced oxidative stress by upregulating nuclear factor erythroid 2-related factor 2 (Nrf2). Treatment of LPS-induced endotoxemia mice with DHF reduced the expression levels of pro-inflammatory mediators via the inactivation of NF-κB, AP-1, and signal transducer and activator of transcription 1 (STAT1) in the lung tissue, thus increasing the survival rate.

CONCLUSION

Taken together, our data first time revealed the underlying mechanism of the DHF-dependent anti-inflammatory effect by preventing LPS from binding to the TLR4/MD2 complex. Therefore, DHF may be a possible anti-inflammatory agent for the treatment of LPS-mediated inflammatory diseases.

Autophagy and apoptosis cascade: which is more prominent in neuronal death?

Autophagy and apoptosis are two crucial self-destructive processes that maintain cellular homeostasis, which are characterized by their morphology and regulated through signal transduction mechanisms. These pathways determine the fate of cellular organelle and protein involved in human health and disease such as neurodegeneration, cancer, and cardiovascular disease. Cell death pathways share common molecular mechanisms, such as mitochondrial dysfunction, oxidative stress, calcium ion concentration, reactive oxygen species, and endoplasmic reticulum stress. Some key signaling molecules such as p53 and VEGF mediated angiogenic pathway exhibit cellular and molecular responses resulting in the triggering of apoptotic and autophagic pathways. Herein, based on previous studies, we describe the intricate relation between cell death pathways through their common genes and the role of various stress-causing agents. Further, extensive research on autophagy and apoptotic machinery excavates the implementation of selective biomarkers, for instance, mTOR, Bcl-2, BH3 family members, caspases, AMPK, PI3K/Akt/GSK3β, and p38/JNK/MAPK, in the pathogenesis and progression of neurodegenerative diseases. This molecular phenomenon will lead to the discovery of possible therapeutic biomolecules as a pharmacological intervention that are involved in the modulation of apoptosis and autophagy pathways. Moreover, we describe the potential role of micro-RNAs, long non-coding RNAs, and biomolecules as therapeutic agents that regulate cell death machinery to treat neurodegenerative diseases. Mounting evidence demonstrated that under stress conditions, such as calcium efflux, endoplasmic reticulum stress, the ubiquitin-proteasome system, and oxidative stress intermediate molecules, namely p53 and VEGF, activate and cause cell death. Further, activation of p53 and VEGF cause alteration in gene expression and dysregulated signaling pathways through the involvement of signaling molecules, namely mTOR, Bcl-2, BH3, AMPK, MAPK, JNK, and PI3K/Akt, and caspases. Alteration in gene expression and signaling cascades cause neurotoxicity and misfolded protein aggregates, which are characteristics features of neurodegenerative diseases. Excessive neurotoxicity and misfolded protein aggregates lead to neuronal cell death by activating death pathways like autophagy and apoptosis. However, autophagy has a dual role in the apoptosis pathways, i.e., activation and inhibition of the apoptosis signaling. Further, micro-RNAs and LncRNAs act as pharmacological regulators of autophagy and apoptosis cascade, whereas, natural compounds and chemical compounds act as pharmacological inhibitors that rescue neuronal cell death through inhibition of apoptosis and autophagic cell death.

Antioxidant Activity and Anti-Apoptotic Effect of the Small Molecule Procyanidin B1 in Early Mouse Embryonic Development Produced by Somatic Cell Nuclear Transfer

As an antioxidant, procyanidin B1(PB1) can improve the development of somatic cell nuclear transfer (SCNT) embryos; PB1 reduces the level of oxidative stress (OS) during the in vitro development of SCNT embryos by decreasing the level of reactive oxygen species (ROS) and increasing the level of glutathione (GSH) and mitochondrial membrane potential (MMP). Metabolite hydrogen peroxide (H₂O₂) produces OS. Catalase (CAT) can degrade hydrogen peroxide so that it produces less toxic water (H₂O) and oxygen (O₂) in order to reduce the harm caused by H₂O₂. Therefore, we tested the CAT level in the in vitro development of SCNT embryos; it was found that PB1 can increase the expression of CAT, indicating that PB1 can offset the harm caused by oxidative stress by increasing the level of CAT. Moreover, if H₂O₂ accumulates excessively, it produces radical-(HO-) through Fe^2+/3+ and damage to DNA. The damage caused to the DNA is mainly repaired by the protein encoded by the DNA damage repair gene. Therefore, we tested the expression of the DNA damage repair gene, OGG1. It was found that PB1 can increase the expression of OGG1 and increase the expression of protein. Through the above test, we proved that PB1 can improve the repairability of DNA damage. DNA damage can lead to cell apoptosis; therefore, we also tested the level of apoptosis of blastocysts, and we found that PB1 reduced the level of apoptosis. In summary, our results show that PB1 reduces the accumulation of H₂O₂ by decreasing the level of OS during the in vitro development of SCNT embryos and improves the repairability of DNA damage to reduce cell apoptosis. Our results have important significance for the improvement of the development of SCNT embryos in vitro and provide important reference significance for diseases that can be treated using SCNT technology.

Dry heated sorghum BRS 305 hybrid flour as a source of resistant starch and tannins improves inflammation and oxidative stress in Wistar rats fed with a high-fat high-fructose diet

This study aimed to evaluate the effect of dry heated sorghum BRS 305 hybrid flour, as a rich source of resistant starch and tannins, on inflammation and oxidative stress in animals fed with a high-fat high-fructose diet. Phase 1 (8 weeks): male Wistar rats were divided into a group fed with an AIN-93 M diet (n = 10) and a group fed with a high-fat (35%) high-fructose (20%) (HFHF) diet (n = 20). Phase 2 (intervention 10 weeks): the control group was continued with the AIN-93 M diet (n = 10) and the HFHF group was divided into HFHF (n = 10) and sorghum flour (n = 10) groups. Sorghum flour decreased the NO, Akt, p65-NFκB, TLR4, and lipid peroxidation in the liver. Furthermore, sorghum flour improved SOD and CAT activities and the total antioxidant capacity of plasma. The phenolic compounds found in sorghum flour interacted in silico with AKT and p65-NFκB, mainly quercetin-3-rutinoside that showed the highest interaction with AKT (EFE -8.0) and procyanidins B1 and B2 that showed the highest interaction with p65-NFκB (EFE -8.9). The consumption of BRS 305 sorghum with a high tannin and resistant starch content improved inflammation and oxidative stress by inhibition of p65-NFκB activation in rats fed a high-fat high-fructose diet.

Procyanidin B2 induces porcine skeletal slow-twitch myofiber gene expression by AMP-activated protein kinase signaling pathway

In this study, our aim is to investigate the effect of dimer procyanidin B2 [epicatechin-(4β-8)-epicatechin] (PB2) on porcine skeletal myofiber gene expression in vitro. Our data showed PB2 promoted the protein expression of slow myosin heavy chain (MyHC) in porcine myotubes, concomitant with the increases in mRNA levels of MyHC I, MyHC IIa and Tnni1. We also found PB2 activated AMPK signaling in porcine myotubes. NRF1 and CaMKKβ that are two important upstream factors of AMPK, and Sirt1 and PGC-1α that are two major downstream factors of AMPK, were also up-regulated by PB2. The mechanism study showed the effect of PB2 on slow-twitch myofiber gene expression was abolished by AMPK inhibitor compound C or by AMPKα1 siRNA. Together, we found PB2 induced porcine skeletal slow-twitch myofiber gene expression by AMPK signaling pathway.

A phytochemical-based medication search for the SARS-CoV-2 infection by molecular docking models towards spike glycoproteins and main proteases

Identifying best bioactive phytochemicals from different medicinal plants using molecular docking techniques demonstrates a potential pre-clinical compound discovery against SARS-CoV-2 viral infection. The in silico screening of bioactive phytochemicals with the two druggable targets of SARS-CoV-2 by simple precision/extra precision molecular docking methods was used to compute binding affinity at its active sites. phyllaemblicin and cinnamtannin class of phytocompounds showed a better binding affinity range (-9.0 to -8.0 kcal mol-1) towards both these SARS-CoV-2 targets; the corresponding active site residues in the spike protein were predicted as: Y453, Q496, Q498, N501, Y449, Q493, G496, T500, Y505, L455, Q493, and K417; and Mpro: Q189, H164, H163, P168, H41, L167, Q192, M165, C145, Y54, M49, and Q189. Molecular dynamics simulation further established the structural and energetic stability of protein-phytocompound complexes and their interactions with their key residues supporting the molecular docking analysis. Protein-protein docking using ZDOCK and Prodigy server predicted the binding pose and affinity (-13.8 kcal mol-1) of the spike glycoprotein towards the human ACE2 enzyme and also showed significant structural variations in the ACE2 recognition site upon the binding of phyllaemblicin C compound at their binding interface. The phyllaemblicin and cinnamtannin class of phytochemicals can be potential inhibitors of both the spike and Mpro proteins of SARS-CoV-2; furthermore, its pharmacology and clinical optimization would lead towards novel COVID-19 small-molecule therapy.

Down-regulation of LncRNA 2900052N01Rik inhibits LPS-induced B cell function in vitro

B cells play a crucial role in immune responses. The main functions include B cell protective antibody production, inflammation reduction, activation and proliferation. Long non-coding RNAs (lncRNAs) have been reported to act as important regulators of many pathological processes. However, few lncRNAs have been reported to affect B cell function. In this study, we explored the expression and role of lncRNA 2900052N01Rik (lnc-290) in lipopolysaccharide (LPS)-induced B cells purified from mouse spleens in vitro. Here, we confirmed that lnc-290 was highly expressed in B cells stimulated by LPS. Knockdown of lnc-290 inhibited the expression of CD69/CD86 and the growth of B cells. Moreover, down-regulated lnc-290 reduced B cell differentiation and immunoglobulin production in vitro. In addition, we found that lnc-290 regulated LPS-induced B cell activation via the NF-κB/ERK pathways. Interestingly, abnormal lnc-290 expression did not alter the B cell activation or proliferation induced by IL-4 or CD40/CD40L. Accordingly, these results indicated, for the first time, that lnc-290 down-regulation inhibits LPS-induced B cell proliferation, activation and differentiation by blocking the LPS/TLR4 signaling pathway. Together, the in vitro data demonstrate that lnc-290 participated in the inflammation and tissue damage mediated by LPS-activated B cells.

Procyanidin B1 promotes in vitro maturation of pig oocytes by reducing oxidative stress

Oxidative stress negatively affects the in vitro maturation (IVM) of oocytes. Procyanidin B1 (PB1) is a natural polyphenolic compound that has antioxidant properties. In this study, we investigated the effect of PB1 supplementation during IVM of porcine oocytes. Treatment with 100 μM PB1 significantly increased the MII oocytes rate (p <0.05), the parthenogenetic (PA) blastocyst rate (p <0.01) and the total cell number in the PA blastocyst (p < 0.01) which were cultured in regular in vitro culture (IVC) medium. The PA blastocyst rate of regular MII oocytes activated and cultured in IVC medium supplemented with 100 and 150 μM PB1 significantly increased compared with control (p < 0.01 and p < 0.05). We also evaluated the reactive oxygen species (ROS) levels, mitochondrial membrane potential (Δψm) levels, glutathione (GSH) levels, and apoptotic levels in MII oocytes and cumulus cells following 100 μM PB1 treatment. The results showed that the PB1 supplementation decreased ROS production and apoptotic levels. In addition, PB1 was found to increase Δψm levels and GSH levels. In conclusion, PB1 inhibited apoptosis of oocytes and cumulus cells by reducing oxidative stress. Moreover, PB1 improved the quality of oocytes and promoted PA embryo development. Taken together, our results suggest that PB1 is a promising antioxidant additive for IVM of oocytes.

GABA-mediated activated microglia induce neuroinflammation in the hippocampus of mice following cold exposure through the NLRP3 inflammasome and NF-κB signaling pathways

Chronic cold stress has long-term dramatic effects on the animal immune and neuroendocrine systems. As one of the important regions of the brain, the hippocampus is the main region involved in response to stressors. Nevertheless, the impact to the hippocampus following cold exposure and the underlying mechanism involved are not clear. To evaluate the response of the hippocampus during chronic cold stress, male C57BL/6 mice were exposed to 4 °C, 3 h per day for 1 week, after which neuroinflammation and the molecular and signaling pathways in the hippocampus response to cold stress were investigated. To confirm the potential mechanism, BV2 cells were treated with γ-aminobutyric acid (GABA) and BAY 11-7082 and MCC950, then the activation of microglia and key proteins involved in the regulation of inflammation were measured. We demonstrated that chronic cold stress induced the activation of microglia, the emergence of neuroinflammation, and the impairment of neurons in the hippocampus, which might be the result of GABA-mediated activation of nod-like receptor protein 3 (NLRP3) inflammasome and the nuclear factor kappa B (NF-κB) signaling pathway.

The anti-inflammatory and antioxidant effects of acute consumption of pigmented rice in humans

The pathogenesis of lifestyle diseases has been significantly correlated to high levels of oxidative stress and pro-inflammation. The antioxidant and anti-inflammatory properties of polyphenols in coloured rice varieties could have potential to neutralize oxidative stress and modulate inflammatory responses. A cross-over design, randomised, dietary intervention human clinical trial was conducted on a pre-screened healthy population (n = 24) investigating the antioxidant and anti-inflammatory potential of pigmented rice (purple, red and brown) varieties. Post baseline blood samples collection volunteers consumed a serve of cooked pigmented rice. Blood samples were collected at 30-minutes, 1, 2 and 4-hours post rice consumption. A one-week wash-out period between each supplementation bout (rice variety) was conducted. Blood and biochemical parameters were analysed on baseline blood samples. Antioxidant activity, malondialdehyde (MDA) and a pro-inflammatory cytokine panel were analysed on the blood samples collected. Post purple rice consumption, antioxidant activity increased (p < 0.0001) by 70.5% and maintained elevated for all time points. The red rice variety Yunlu29, significantly (p < 0.005) reduced MDA levels by 9.2% at the 30-minute time point. Purple rice demonstrated a significant (p < 0.05) decrease by 4.0% at the 30-minute time point only. Purple rice significantly decreased TNF-α levels at the 1-hour (p < 0.05) and 4-hour (p < 0.005) time points by 21.9% and 25.4% respectively. IL-6 concentrations were significantly reduced at 1 and 2-hour post Purple (p < 0.05; 11.7%) and Yunlu29 (red) (p < 0.01; 14.1%) consumption respectively. The brown rice variety did not affect any parameters tested. The outcomes of this study, highlight that polyphenols found in pigmented rice may play a key role in targeting specific oxidative stress and inflammatory therapeutic pathways. Pigmented rice varieties may serve as a potential functional food in reducing risk factors associated with lifestyle diseases.

Anti-Inflammatory Constituents From Chaenomeles speciosa

Phytochemical investigation of fruits of Chaenomeles speciosa Lindley (Rosaceae) led to the isolation of 20 compounds including 5 flavonoids (1-5), 5 phenylpropanoids (6-10), 3 benzoic acid derivatives (11-13), 2 phloroglucinols (14 and 15), 2 purines (16 and 17), and 3 terpenoids (18–20). Their structures were elucidated by nuclear magnetic resonance analyses and from mass spectrometry data. These compounds were confirmed as catechin (1), epicatechin (2), catechin-5- O-β-d-glucoside (3), procyanidin B1 (4), quercetin-3- O-β-d-glucoside (5), p-coumaric acid (6), ferulic acid (7), caffeic alcohol (8), 1- O-p-coumaroyl-β-d-glucose (9), 1- O-cinnamoyl-β-d-glucose (10), p-hydroxybenzonic acid (11), protocatechuic acid (12), benzoic acid-β-d-gentiobioside (13), phloracetophenone 4′-glucoside (14), 3,5-dihydroxyphenyl β-d-glucopyranoside (15), adenine (16), adenosine (17), betulalbuside A (18), vomifoliol (19), and roseoside (20). Compounds 3-5, 8, 10, and 13-18 were isolated from the genus Chaenomeles and C. speciosa for the first time. Out of all these, compound 17 showed the best anti-inflammatory properties, comparable with those of the already known minocycline.

Health-Promoting Properties of Proanthocyanidins for Intestinal Dysfunction

The intestinal barrier is constantly exposed to potentially harmful environmental factors, including food components and bacterial endotoxins. When intestinal barrier function and immune homeostasis are compromised (intestinal dysfunction), inflammatory conditions may develop and impact overall health. Evidence from experimental animal and cell culture studies suggests that exposure of intestinal mucosa to proanthocyanidin (PAC)-rich plant products, such as grape seeds, may contribute to maintaining the barrier function and to ameliorating the pathological inflammation present in diet-induced obesity and inflammatory bowel disease. In this review, we aim to update the current knowledge on the bioactivity of PACs in experimental models of intestinal dysfunction and in humans, and to provide insights into the underlying biochemical and molecular mechanisms.

Proanthocyanidins of Natural Origin: Molecular Mechanisms and Implications for Lipid Disorder and Aging-Associated Diseases

Proanthocyanidins are phytonutrients formed by oligomerization or polymerization of subunits catechin, epicatechin, and their gallic acid esters. Proanthocyanidins are a component of many plants and thus form an integral part of the human diet. Oligomeric proanthocyanidins are currently marketed as medicinal products that target vascular disorders and chronic pathological conditions, many of which are age-associated. Proanthocyanidins are also characterized by their effects on energy homeostasis. Not dissimilar to their chemically synthesized counterparts, naturally extracted proanthocyanidins act via inhibition of lipases, stimulation of energy expenditure, or suppression of appetite. Here we review the current knowledge-base and highlight challenges and future impacts regarding involvement of proanthocyanidins in global lipid metabolism, with a focus on the molecular mechanisms and pathological conditions that progress with aging.

Licochalcone A Protects the Blood-Milk Barrier Integrity and Relieves the Inflammatory Response in LPS-Induced Mastitis

Background/Aims: Mastitis is an acute clinical inflammatory response. The occurrence and development of mastitis seriously disturb women's physical and mental health. Licochalcone A, a phenolic compound in Glycyrrhiza uralensis, has anti-inflammatory properties. Here, we examined the effect of licochalcone A on blood-milk barrier and inflammatory response in LPS-induced mice mastitis.

Methods:In vivo, we firstly established mice models of mastitis by canal injection of LPS to mammary gland, and then detected the effect of licochalcone A on pathological indexes, inflammatory responses and blood-milk barrier in this model. In vivo, Mouse mammary epithelial cells (mMECs) were treated with licochalcone A prior to the incubation of LPS, and then the inflammatory responses, tight junction which is the basic structure of blood-milk barrier were analyzed. Last, we elucidated the anti-inflammatory mechanism by examining the activation of mitogen-activated protein kinase (MAPK) and AKT/NF-κB signaling pathways in vivo and in vitro.

Result: The in vivo results showed that licochalcone A significantly decreased the histopathological impairment and the inflammatory responses, and improved integrity of blood-milk barrier. The in vitro results demonstrated that licochalcone A inhibited LPS-induced inflammatory responses and increase the protein levels of ZO-1, occludin, and claudin3 in mMECs. The in vivo and in vitro mechanistic study found that the anti-inflammatory effect of licochalcone A in LPS-induced mice mastitis was mediated by MAPK and AKT/NF-κB signaling pathways.

Conclusions and Implications: Our experiments collectively indicate that licochalcone A protected against LPS-induced mice mastitis via improving the blood–milk barrier integrity and inhibits the inflammatory response by MAPK and AKT/NF-κB signaling pathways.

Lotus seed skin proanthocyanidin extract exhibits potent antioxidant property via activation of the Nrf2-ARE pathway

Lotus seed is well known as traditional food and medicine, but its skin is usually discarded. Recent studies have shown that lotus seed skin contains a high concentration of proanthocyanidins that have multi-functions, such as antioxidation, anti-inflammation, and anti-cancer effects. In the present study, we aimed to isolate and purify the proanthocyanidins from lotus seed skin by acetone extraction and rotary evaporation, identify their chemical structures by HPLC-MS-MS and NMR, and further investigate the antioxidant properties of the extract purified by macroporous resin (PMR) from lotus seed skin both in vitro and in vivo. The results showed that PMR mainly contained oligomeric proanthocyanidins, especially dimeric procyanidin B1 (PB1), procyanidin B2 and procyanidin B4. Although it had limited ability to directly scavenge radicals in vitro, PMR could significantly enhance the expressions of antioxidant proteins via activation of nuclear factor-E2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway in HepG2 cells. Molecular data revealed that PB1, a major component in PMR, stabilized Nrf2 by inhibiting the ubiquitination of Nrf2, which led to subsequent activation of the Nrf2-ARE pathway, including the enhancements of Nrf2 nuclear translocation, Nrf2-ARE binding and ARE transcriptional activity. Moreover, the in vivo results in high fat diet-induced mice further verified the powerful antioxidant property of PMR. These results revealed that lotus seed skin is a promising resource for functional food development.

Epimedium sagittatum inhibits TLR4/MD-2 mediated NF-κB signaling pathway with anti-inflammatory activity

BACKGROUND

Epimedium sagittatum (Sieb.et Zucc.) Maxim., Ying-Yang-Huo in Chinese has been used as a traditional Chinese medicine and is deemed to "reinforce the kidney Yang". Previous studies showed that E. sagittatum could modulate the immune system and treat some chronic disease such as rheumatic arthritis, cardiovascular diseases and osteoporosis. The aim of this study is to evaluate the anti-inflammatory effects of ethyl acetate extracts (YYHs) of E. sagittatum and its mechanisms of action.

METHODS

In order to explore the composition of YYHs, YYHs was analyzed using high performance liquid chromatography-mass spectrometry-mass spectrometry (HPLC-MS/MS) and in comparison with reference standards. Anti-inflammatory model was established in LPS-induced RAW264.7 cells. The levels of nitric oxide (NO) were measured with the Griess reagent. Production of tumor necrosis factor-alpha (TNF-α) and interleukin-2 (IL-2) were measured by enzyme-linked immunosorbent assays (ELISA). In addition, expression of p-p65 protein and TLR4/MD-2 complex was detected by western blots and flow cytometric, respectively. Nuclear factor kappa B (NF-κB) nuclear translocation was observed by fluorescence microscope.

RESULTS

A total of eight compounds were identified, of which icariside II was the most abundant compound. YYHs (12.5-50 μg/mL) had no obvious cytotoxic effect on cells, and remarkably inhibited LPS-induced production of NO, TNF-α and IL-2 with a dose-dependent manner. Additionally, YYHs up-regulated expression of p-p65 and TLR4/MD-2 complex. Further research showed that YYHs significantly suppressed NF-κB p65 nuclear translocation.

CONCLUSION

In brief, YYHs contributed to the inhibition of LPS-induced inflammatory response through the TLR4/MD-2-mediated NF-κB pathway and may be a potential choice to combat inflammation diseases. It includes a schema of pathways at the end of the paper.

Computational Molecular Docking and X-ray Crystallographic Studies of Catechins in New Drug Design Strategies

Epidemiological and laboratory studies have shown that green tea and green tea catechins exert beneficial effects on a variety of diseases, including cancer, metabolic syndrome, infectious diseases, and neurodegenerative diseases. In most cases, (-)-epigallocatechin gallate (EGCG) has been shown to play a central role in these effects by green tea. Catechins from other plant sources have also shown health benefits. Many studies have revealed that the binding of EGCG and other catechins to proteins is involved in its action mechanism. Computational docking analysis (CMDA) and X-ray crystallographic analysis (XCA) have provided detailed information on catechin-protein interactions. Several of these studies have revealed that the galloyl moiety anchors it to the cleft of proteins through interactions with its hydroxyl groups, explaining the higher activity of galloylated catechins such as EGCG and epicatechin gallate than non-galloylated catechins. In this paper, we review the results of CMDA and XCA of EGCG and other plant catechins to understand catechin-protein interactions with the expectation of developing new drugs with health-promoting properties.

Discovery and preliminary SAR of 14-aryloxy-andrographolide derivatives as antibacterial agents with immunosuppressant activity

Antibacterials (which restore gut flora balance) and immunosuppressants (which correct immune defects) are two important and effective therapeutic agents for the treatment of inflammatory bowel disease (IBD) in clinical use today. Since the structural skeleton of andrographolide, isolated from Andrographis paniculata, has become known as a natural antibiotic with anti-inflammation and heat-clearing and detoxifying properties, 14-aryloxy andrographolide derivatives have been designed, synthesized, and tested for their antibacterial effects on E. coli, S. aureus, and E. faecalis, which are related to IBD. It has been discovered in this study that the andrographolide skeleton is more selective against E. faecalis, the 14-aryloxy group with basicity is important for antibacterial functions, and the 14-(8'-quinolinyloxy) group is a good pharmacophore with antibacterial activity. In addition, we found that 7b1 and 8b1 are good and selective inhibitors of E. faecalis; two 14β-(8'-quinolinyloxy) andrographolide derivatives, 6b17 and 9b, exhibit good activity against E. coli, S. aureus, and E. faecalis. Likewise and importantly, further exploration of immunosuppressant activity for IBD shows that compound 7b1 is a selective inhibitor of the TNF-α/NF-κB signaling pathway, whereas 8b1 is selectively active against the TLR4/NF-κB signaling pathway; moreover, the compounds 6b17 and 9b are active in inhibiting the IL-6/STAT3, TLR4/NF-κB, and TNF-α/NF-κB signaling pathways. Based on these results, we have further focused on the development of dual function inhibitors of IBD as antibacterial and immunosuppressant agents by structural modification of andrographolide.

Attenuation of Innate Immunity by Andrographolide Derivatives Through NF-κB Signaling Pathway

Andrographolide derivatives or analogs exhibit potent anti-inflammatory effects in several disease models through NF-κB activity. In this study, we synthesized different andrographolide derivatives and investigated their effects on the toll-like receptor (TLR)-induced production of pro-inflammatory cytokines. Among these compounds, 3b, 5a, and 5b inhibited both TNF-α/NF-κB and TLR4/NF-κB signaling pathways. Treatment with compounds 3b, 5a, and 5b and their structural analogs, 3a and 6b, suppressed the expression of pro-inflammatory cytokines upon the activation of TLR3 and TLR4 ligands. Compounds 3b and 5a, but not 3a, 5b, or 6b, inhibited the nuclear translocation of the NF-κB p65 subunit. Treatment with compounds 3b, 5a, 3a, 5b, and 6b attenuated the phosphorylation of p65 and IκBα. Compounds 6b suppressed the expression of the NF-κB p65 subunit. However, these compounds, except for 5b, did not affect the TLR9-induced NF-κB-independent production of the pro-inflammatory cytokines, TNF-α, and IFN-β. Compound 3b potentially protected mice from LPS-induced acute pulmonary inflammation through the inhibition of p65 phosphorylation and the decrease of serum pro-inflammatory cytokines and chemokine. Our study revealed a functional structure–activity relationship between andrographolide derivatives and innate immunity. We identified compound 3b as a potent immune suppressive agent with the potential to protect acute pulmonary infection.

Procyanidins Mitigate Osteoarthritis Pathogenesis by, at Least in Part, Suppressing Vascular Endothelial Growth Factor Signaling

Procyanidins are a family of plant metabolites that have been suggested to mitigate osteoarthritis pathogenesis in mice. However, the underlying mechanism is largely unknown. This study aimed to determine whether procyanidins mitigate traumatic injury-induced osteoarthritis (OA) disease progression, and whether procyanidins exert a chondroprotective effect by, at least in part, suppressing vascular endothelial growth factor signaling. Procyanidins (extracts from pine bark), orally administered to mice subjected to surgery for destabilization of the medial meniscus, significantly slowed OA disease progression. Real-time polymerase chain reaction revealed that procyanidin treatment reduced expression of vascular endothelial growth factor and effectors in OA pathogenesis that are regulated by vascular endothelial growth factor. Procyanidin-suppressed vascular endothelial growth factor expression was correlated with reduced phosphorylation of vascular endothelial growth factor receptor 2 in human OA primary chondrocytes. Moreover, components of procyanidins, procyanidin B2 and procyanidin B3 exerted effects similar to those of total procyanidins in mitigating the OA-related gene expression profile in the primary culture of human OA chondrocytes in the presence of vascular endothelial growth factor. Together, these findings suggest procyanidins mitigate OA pathogenesis, which is mediated, at least in part, by suppressing vascular endothelial growth factor signaling.

Anti-Inflammatory Effects of Chloranthalactone B in LPS-Stimulated RAW264.7 Cells

Chloranthalactone B (CTB), a lindenane-type sesquiterpenoid, was obtained from the Chinese medicinal herb Sarcandra glabra, which is frequently used as a remedy for inflammatory diseases. However, the anti-inflammatory mechanisms of CTB have not been fully elucidated. In this study, we investigated the molecular mechanisms underlying these effects in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. CTB strongly inhibited the production of nitric oxide and pro-inflammatory mediators such as prostaglandin E₂, tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and IL-6 in RAW264.7 cells stimulated with LPS. A reverse-transcription polymerase chain reaction assay and Western blot further confirmed that CTB inhibited the expression of inducible nitric oxide synthase, cyclooxygenase-2, TNF-α, and IL-1β at the transcriptional level, and decreased the luciferase activities of activator protein (AP)-1 reporter promoters. These data suggest that inhibition occurred at the transcriptional level. In addition, CTB blocked the activation of p38 mitogen-activated protein kinase (MAPK) but not c-Jun N-terminal kinase or extracellular signal-regulated kinase 1/2. Furthermore, CTB suppressed the phosphorylation of MKK3/6 by targeting the binding sites via formation of hydrogen bonds. Our findings clearly show that CTB inhibits the production of inflammatory mediators by inhibiting the AP-1 and p38 MAPK pathways. Therefore, CTB could potentially be used as an anti-inflammatory agent.

Computational Approaches to Toll-Like Receptor 4 Modulation

Toll-like receptor 4 (TLR4), along with its accessory protein myeloid differentiation factor 2 (MD-2), builds a heterodimeric complex that specifically recognizes lipopolysaccharides (LPS), which are present on the cell wall of Gram-negative bacteria, activating the innate immune response. Some TLR4 modulators are undergoing preclinical and clinical evaluation for the treatment of sepsis, inflammatory diseases, cancer and rheumatoid arthritis. Since the relatively recent elucidation of the X-ray crystallographic structure of the extracellular domain of TLR4, research around this fascinating receptor has risen to a new level, and thus, new perspectives have been opened. In particular, diverse computational techniques have been applied to decipher some of the basis at the atomic level regarding the mechanism of functioning and the ligand recognition processes involving the TLR4/MD-2 system at the atomic level. This review summarizes the reported molecular modeling and computational studies that have recently provided insights into the mechanism regulating the activation/inactivation of the TLR4/MD-2 system receptor and the key interactions modulating the molecular recognition process by agonist and antagonist ligands. These studies have contributed to the design and the discovery of novel small molecules with promising activity as TLR4 modulators.

Strawberry tannins inhibit IL-8 secretion in a cell model of gastric inflammation

In the present study we chemically profiled tannin-enriched extracts from strawberries and tested their biological properties in a cell model of gastric inflammation. The chemical and biological features of strawberry tannins after in vitro simulated gastric digestion were investigated as well. The anti-inflammatory activities of pure strawberry tannins were assayed to get mechanistic insights. Tannin-enriched extracts from strawberries inhibit IL-8 secretion in TNFα-treated human gastric epithelial cells by dampening the NF-κB signaling. In vitro simulated gastric digestion slightly affected the chemical composition and the biological properties of strawberry tannins. By using pure compounds, we found that casuarictin may act as a pure NF-κB inhibitor while agrimoniin inhibits IL-8 secretion also acting on other biological targets; in our system procyanidin B1 prevents the TNFα-induced effects without interfering with the NF-κB pathway. We conclude that strawberry tannins, even after in vitro simulated gastric digestion, exert anti-inflammatory activities at nutritionally relevant concentrations.

Anti-inflammatory effects and molecular mechanisms of 8-prenyl quercetin

SCOPE

8-prenyl quercetin (PQ) is a typical prenylflavonoid distributed in plant foods. It shows higher potential bioactivity than its parent quercetin (Q) although the mechanisms are not fully understood. This study aims to clarify the anti-inflammatory effects and molecular mechanisms of PQ in cell and animal models, compared to Q.

METHODS AND RESULTS

RAW264.7 cells were treated with PQ or Q to investigate the influence on the production of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and protein kinases by Western blotting. Nitric oxide (NO) and prostaglandin E2 (PGE2 ) were measured by the Griess method and ELISA, respectively. Cytokines were assayed by the multiplex technology. Mouse paw edema was induced by LPS. The results revealed that PQ had stronger inhibition on the production of iNOS, COX-2, NO, PGE2 , and 12 kinds of cytokines, than Q. PQ also showed in vivo anti-inflammatory effect by attenuating mouse paw edema. Molecular data revealed that PQ had no competitive binding to Toll-like receptor 4 with LPS, but directly targeted SEK1-JNK1/2 (where SEK is stress-activated protein kinase and JNK1/2 is Jun-N-terminal kinase 1/2) and MEK1-ERK1/2 (where ERK is extracellular signal regulated kinase).

CONCLUSION

PQ as a potential inhibitor revealed anti-inflammatory effect in both cell and animal models at least by targeting SEK1-JNK1/2 and MEK1-ERK1/2.