Herbal formula SC-E1 suppresses lipopolysaccharide-stimulated inflammatory responses through activation of Nrf2/HO-1 signaling pathway in RAW 264.7 macrophages

Licorice extract inhibits porcine epidemic diarrhea virus in vitro and in vivo

Porcine epidemic diarrhea virus (PEDV) causes severe diarrhea and even death in piglets, resulting in significant economic losses to the pig industry. Because of the ongoing mutation of PEDV, there might be variations between the vaccine strain and the prevailing strain, causing the vaccine to not offer full protection against different PEDV variant strains. Therefore, it is necessary to develop anti-PEDV drugs to compensate for vaccines. This study confirmed the anti-PEDV effect of licorice extract (Le) in vitro and in vivo. Le inhibited PEDV replication in a dose-dependent manner in vitro. By exploring the effect of Le on the life cycle of PEDV, we found that Le inhibited the attachment, internalization, and replication stages of the virus. In vivo, all five piglets in the PEDV-infected group died within 72 h. In comparison, the Le-treated group had a survival rate of 80 % at the same time, with significant relief of clinical symptoms, pathological damage, and viral loads in the jejunum and ileum. Our results suggested that Le can exert anti-PEDV effects in vitro and in vivo. Le is effective and inexpensive; therefore it has the potential to be developed as a new anti-PEDV drug.

Recent advances in Platycodon grandiflorum polysaccharides: Preparation techniques, structural features, and bioactivities

Platycodon grandiflorum, a globally recognized medicinal and edible plant, possesses significant nutritional value and pharmacological value. In traditional Chinese medicine, it has the effects of tonifying the spleen and replenishing the Qi, moistening the lung and relieving the cough, clearing the heat and detoxifying, and relieving the pain. Accumulating evidence has revealed that the polysaccharides from P. grandiflorum (PGPs) are one of the major and representative biologically active macromolecules and have diverse biological activities, such as immunomodulatory activity, anti-inflammatory activity, anti-tumor activity, regulation of the gut microbiota, anti-oxidant activity, anti-apoptosis activity, anti-angiogenesis activity, hypoglycemic activity, anti-microbial activity, and so on. Although the polysaccharides extracted from P. grandiflorum have been extensively studied for the extraction and purification methods, structural characteristics, and pharmacological activities, the knowledge of their structures and bioactivity relationship, toxicologic effects, and pharmacokinetic profile is limited. The main purpose of the present review is to provide comprehensively and systematically reorganized information on extraction and purification, structure characterizations, and biological functions as well as toxicities of PGPs to support their therapeutic potentials and sanitarian functions. New valuable insights for future research regarding PGPs were also proposed in the fields of therapeutic agents and functional foods.

Heme Oxygenase 1-Mediated Anti-Inflammatory Effect of Extract from the Aerial Part of Heracleum moellendorffii Hance

In this study, the anti-inflammatory effects of a methanolic extract from the aerial part of Heracleum moellendorffii Hance (HmAPE) and its underlying mechanisms were investigated. HmAPE demonstrated a significant reduction in nitric oxide production in lipopolysaccharide (LPS)-treated murine macrophage RAW264.7 cells, and HmAPE decreased the protein and mRNA expression of inducible nitric oxide synthase. Further mechanistic studies on inflammatory signaling pathways revealed that HmAPE-mediated downregulation of inflammatory gene expressions was not associated with mitogen-activated protein kinases or nuclear factor-κB signaling pathways. However, HmAPE treatment activated nuclear factor E2-related factor 2 (Nrf2) and upregulated heme oxygenase-1 (HO-1) expression, which is known to suppress pro-inflammatory cytokine production. Additionally, treatment with a selective HO-1 inhibitor, tin protoporphyrin IX, partially reversed the effects of HmAPE in LPS-treated RAW264.7 cells, indicating that HmAPE inhibited LPS-induced NO production, at least in part, through induction of Nrf2-mediated HO-1 expression. These findings suggest that HmAPE could serve as a potential edible source with anti-inflammatory properties, and further studies are required to ascertain its anti-inflammatory efficacy in vivo.

Bullatine A exerts anti-inflammatory effects by inhibiting the ROS/JNK/NF-κB pathway and attenuating systemic inflammatory responses in mice

CONTEXT

Aconiti brachypodi Radix (Xue-shang-yi-zhi-hao) is a traditional Chinese herbal medicine that is capable of anti-analgesic and anti-inflammatory effects. Bullatine A (BA) is one of the major active ingredients of this plant, and most of the previous studies reported that it has anti-analgesic effects. However, the mechanism of BA anti-inflammatory remains unclear.

OBJECTIVE

This study investigates the anti-inflammatory activities of BA, both in vitro and in vivo, and elucidates its mechanism.

MATERIALS AND METHODS

In vitro, BA (10, 20, 40 and 80 μM) was added to 1 µg/mL of lipopolysaccharide (LPS)-activated microglia BV2 cells and immortalized murine bone marrow-derived macrophages, respectively. After 6 h, the mRNA and protein levels of inflammatory factors were determined by real-time quantitative PCR and western blotting. In vivo, C57BL/6 mice were randomly divided into control, model (5 mg/kg dose of LPS) and treated groups (LPS with 5, 10 or 20 mg/kg dose of BA) to evaluate the anti-inflammatory efficacy of BA.

RESULTS

BA significantly inhibited LPS-induced expression of inflammatory factors, such as IL-1β, IL-6, TNF-α, inducible nitric oxide synthase (iNOS) and COX-2. Further investigations showed that BA reduced the translocation of NF-κB p65 (38.5%, p < 0.01). BA also reduced the phosphorylation of c-Jun N-terminal kinase (JNK) (11.2%, p < 0.05) and reactive oxygen species (ROS) generation (24.2%, p < 0.01). Furthermore, BA treatment attenuated the LPS-primed inflammatory response and liver and lung damage in vivo.

CONCLUSIONS

BA can inhibit the inflammatory response in part through the ROS/JNK/NF-κB signalling pathway, providing a theoretical basis for the clinical application of BA in the treatment of periphery inflammatory diseases.

Effects of Plant-Derived Glycerol Monolaurate (GML) Additive on the Antioxidant Capacity, Anti-Inflammatory Ability, Muscle Nutritional Value, and Intestinal Flora of Hybrid Grouper (Epinephelus fuscoguttatus♀ × Epinephelus lanceolatus♂)

In a context where the search for plant-derived additives is a hot topic, glycerol monolaurate (GML) was chosen as our subject to study its effect on grouper (Epinephelus fuscoguttatus♀ × Epinephelus lanceolatus♂). Seven gradient levels of GML (0, 600, 1200, 1800, 2400, 3000, and 3600 mg/kg) were used for the experiment. Based on our experiments, 1800 mg/kg GML significantly increased the final body weight (FBW) and weight gain rate (WGR). GML increased the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and decreased malondialdehyde (MDA). Adding 1800 mg/kg GML also significantly increased the levels of lauric acid (C12:0) (LA), n-3 polyunsaturated fatty acids (PFA), and the n-6 PFA-to-n-3/n-6 ratio, while significantly decreasing the levels of saturated fatty acids (SFA). Dietary supplementation with GML significantly inhibited the expression of pro-inflammatory factors and reduced the occurrence of inflammation. GML improved intestinal flora and the abundance of beneficial bacteria (Bacillus, Psychrobacter, Acinetobacter, Acinetobacter, Stenotrophomonas, and Glutamicibacter). It provides a theoretical basis for the application of GML in aquafeed and greatly enhances the possibility of using GML in aquafeed. Based on the above experimental results, the optimum level of GML in grouper feed is 1800 mg/kg.

An in vivo and in vitro assessment of the anti-breast cancer activity of crude extract and fractions from Prunella vulgaris L

Prunella vulgaris L.(P. vulgaris) is a perennial herb belonging to the Labiate family and widely distributed in China, Japan, Korea and Europe. Medical monographs and previous studies have shown that P. vulgaris has significant anti-breast cancer activity, and its use in breast treatment has a long history. However, systematically reports about the material basis and mechanism of P. vulgaris on anti-breast cancer activity are limited. In the present study, we first screened the best active fraction from the crude extract (PVE) and ethanol eluted fractions of P. vulgaris by using MDA-MB-231, MCF-7, 4T1 cell models in vitro and a 4T1-BALB/c transplanted tumour mouse breast cancer model in vivo. Furthermore, the anti-breast cancer mechanism of the best active fraction was investigated. The results demonstrated that PVE and ethanol fractions exhibited anti-breast cancer activity, especially with the 50% ethanol eluted fraction (PV50), which effectively regulated the 4T1 cell cycle, inhibited tumour cell proliferation, and promoted cancer cell apoptosis. In case of in vivo assays, PV50 inhibited tumour growth and lung metastasis, as well as inducing cell apoptosis by promoting damage of nuclear DNA and increasing expression of cleaved caspase-3. In addition, the chemical compositions of PV50 were analyzed by HPLC and UPLC-MS/MS, which were identified as flavonoids, moderately polar triterpenes, and a small amount of phenolic acid. The PV50 could be applied as natural sources against breast cancer in the pharmaceutical industry. These findings provide a basis for understanding the mechanism of the anti-breast cancer activity of P. vulgaris.

β-Glucan from Saccharomyces cerevisiae alleviates oxidative stress in LPS-stimulated RAW264.7 cells via Dectin-1/Nrf2/HO-1 signaling pathway

β-Glucan from Saccharomyces cerevisiae has been described to be effective antioxidants, but the specific antioxidation mechanism of β-glucan is unclear. The objectives of this research were to determine whether the β-glucan from Saccharomyces cerevisiae could regulate oxidative stress through the Dectin-1/Nrf2/HO-1 signaling pathway in lipopolysaccharides (LPS)-stimulated RAW264.7 cells. In this study, we examined the effects of β-glucan on the enzyme activity or production of oxidative stress indicators in LPS-stimulated RAW264.7 cells by biochemical analysis and the protein expression of key factors of Dectin-1/Nrf2/HO-1 signaling pathway by immunofluorescence and western blot. The biochemical analysis results showed that β-glucan increased the LPS-induced downregulation of enzyme activity of intracellular heme oxygenase (HO), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) while decreasing the production of reactive oxygen species (ROS) and malondialdehyde (MDA). Furthermore, immunofluorescence results showed that β-glucan can activate the nuclear factor erythroid 2-related factor 2 (Nrf2). The antioxidant mechanism study indicated that β-glucan activated dendritic-cell-associated C-type lectin 1 (Dectin-1) receptors mediated Nrf2/HO-1 signaling pathway, thereby downregulating the production of ROS and thus produced the antioxidant effects in LPS-stimulated RAW 264.7 cells. In conclusion, these results indicate that β-glucan potently alleviated oxidative stress via Dectin-1/Nrf2/HO-1 in LPS-stimulated RAW 264.7 cells.

Anti‑inflammatory effect of Chrysanthemum zawadskii, peppermint, Glycyrrhiza glabra herbal mixture in lipopolysaccharide‑stimulated RAW264.7 macrophages

The normal inflammatory reaction protects the body from harmful external factors, whereas abnormal chronic inflammation can cause various diseases, including cancer. The purpose of the present study was to investigate the anti‑inflammatory activity of a mixture of Chrysanthemum zawadskii, peppermint and Glycyrrhiza glabra (CPG) by analyzing the expression levels of inflammatory mediators, cytokines and transcription factors in lipopolysaccharide (LPS)‑stimulated Raw264.7 cells. A nitric oxide assay, ELISA, western blotting and immunofluorescence staining were performed to investigate the anti‑inflammatory activity of the CPG mixture. Pretreatment of Raw264.7 cells with CPG inhibited the increase of inflammatory mediators (inducible nitric oxide synthase, cyclooxygenase‑2 and IFN‑β) induced by LPS. Additionally, it inhibited the production of pro‑inflammatory cytokines (TNF‑α, IL‑6 and IL‑1β). CPG suppressed LPS‑induced phosphorylation of STAT1, AKT, Iκb and NF‑κB. Furthermore, CPG inhibited the translocation of NF‑κB into the nucleus. In summary, CPG could inhibit LPS‑induced inflammation, which occurs primarily through the AKT/Iκb/NF‑κB signaling pathway in RAW264.7 cells.

Polyherbal formula SC-E3 inhibits rheumatoid arthritis activity in a mouse model of type-II collagen-induced arthritis

OBJECTIVE

SC-E3 is a polyherbal formula that contains five medicinal herbs used frequently in traditional herbal medicine. In our previous study, we demonstrated the antioxidant and anti-inflammatory effects of SC-E3. The present study examined the effects of SC-E3 in a mouse model of type-II collagen-induced arthritis (CIA).

METHODS

In vivo, male DBA/1J mice were immunized by intradermal injection of bovine type-II collagen and complete or incomplete Freund's adjuvant, to induce arthritis. SC-E3 was orally administered daily for 23 days. In vitro, bone marrow-derived macrophages (BMMs) were treated with macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor-κB ligand (RANKL) in the absence or presence of SC-E3.

RESULTS

Administrations of SC-E3 were found to have anti-arthritic effects in the joints of CIA mice, as evidenced by reduced paw swelling, bone erosion and deformation, inflammatory cell infiltration, and inflammation in synovial membrane. SC-E3 also reduced serum levels of tumor necrosis factor-α, interleukin-1β, aspartate aminotransferase and alanine aminotransferase. Furthermore, tartrate-resistant acid phosphatase-positive osteoclast numbers in the joints were significantly lower in SC-E3-treated CIA mice than in CIA mice. In addition, the differentiations of BMMs to multinucleated osteoclasts induced by M-CSF and RANKL stimulation were dose-dependently reduced by SC-E3.

CONCLUSION

These results suggest that SC-E3 possesses substantial anti-arthritic activity because it inhibits pro-inflammatory cytokines and osteoclastogenesis, and that SC-E3 has potential therapeutic use for the treatment of rheumatoid arthritis.

Administration of a herbal formulation enhanced blastocyst implantation via IκB activation in mouse endometrium

Background

BaelanChagsangBang (BCB), a herbal formulation consisting of eleven herbs, may be prescribed as a reproductive functional supplement to improve ovulation and implantation during the treatment of infertility and recurrent abortion in Korean Medicine. This study aimed to investigate the effects and action mechanisms of water-extracted BCB on endometrial receptivity and blastocyst implantation under normal conditions and in a mifepristone (RU486)-induced implantation failure murine model.

Methods

In vitro, the antioxidant potentials of BCB were evaluated using DPPH and superoxide anion radical scavenging assays and a DCFH-DA assay, and the cytotoxic and cytoprotective effects of BCB were confirmed using an MTT assay. In vivo, C57BL/6 female mice (n = 6 per group) orally received BCB (300 mg/kg/day), a dose similar to that used clinically, from 7 days before pregnancy until the end of the experiment. On day 4 of pregnancy, RU486 (4 mg/kg) was injected subcutaneously to induce implantation failure. The effect of BCB on embryo implantation was evaluated by implantation rate analysis, histological examination, and western blotting of uterus tissues.

Results

BCB water extract showed strong anti-oxidative and cytoprotective effects in vitro. In vivo administration of BCB water extract increased the number of newborn pups in BCB-treated mice versus sham-treated mice under normal conditions and improved the number of implantation sites in pregnant mice despite RU486 injection. BCB increased the protein levels of cyclooxygenase-2 and inducible nitric oxide synthase through IκB activation. Moreover, the expression levels of matrix metalloproteinases at uterus implantation sites were up-regulated in the BCB-treated group as compared with those in the RU486-treated group.

Conclusion

These results show BCB improved embryo implantation through IκB activation in our mouse model and suggest that BCB has therapeutic potential in the context of poor endometrial receptivity.

Croton hirtus L'Hér Extract Prevents Inflammation in RAW264.7 Macrophages Via Inhibition of NF-κB Signaling Pathway

Consumption of anti-inflammatory nutraceuticals may help treat or prevent inflammation-related illnesses such as diabetes, cardiovascular disease, and cancer. This study evaluated the effect of Croton hirtus L'Hér extract (CHE) on lipopolysaccharide (LPS)-induced nitric oxide (NO) production and nuclear factor kappa-B (NF-κB) signaling cascades. CHE significantly suppressed LPS-induced NO production and inducible nitric oxide synthase (iNOS) expression in RAW264.7 macrophages, although cyclooxygenase (COX)-2 expression was not affected. CHE also suppressed LPS-induced IκB kinase (IKK), IκB, and p65 phosphorylation in RAW264.7 cells. Western blot and immunofluorescence assays of cytosol and nuclear p65 and the catalytic subunit of NF-κB showed that CHE suppressed LPS-induced p65 translocation from the cytosol to the nucleus. CHE also suppressed LPS-induced Interleukin (IL)-6 and tumor necrosis factor (TNF)-α production in RAW264.7 cells. These results suggest that CHE prevents NO-mediated inflammation by suppressing NF-κB and inflammatory cytokines.

Sesamin Enhances Nrf2-Mediated Protective Defense against Oxidative Stress and Inflammation in Colitis via AKT and ERK Activation

Ulcerative colitis (UC) is a major form of inflammatory bowel disease (IBD) with high incidence and prevalence in many countries. Patients with UC usually suffer from a lifetime of debilitating physical symptoms. Therefore, developing effective therapeutic strategy that can manage this disease better and improve patients' life quality is in urgent need. Sesamin (SSM) is a lignan derived from sesame seeds. In this study, the protective effect of SSM against UC and the underlying mechanism were investigated in vitro and in vivo. Our data showed that SSM protected Caco-2 cells from H₂O₂-induced oxidative stress injury via GSH-mediated scavenging of reactive oxygen species (ROS). Dual luciferase reporter assay showed that the transcriptional activity of nuclear factor erythroid-related factor 2 (Nrf2) was significantly increased by SSM, and the ability of SSM to activate Nrf2-targeted genes was further confirmed in Caco-2 cells using western blot and quantitative real-time PCR (qRT-PCR). In contrast, Nrf2 knockdown abolished the protective effect of SSM. Additionally, we found that SSM also activated advanced protein kinase B (AKT) and extracellular signal-regulated kinase (ERK) in Caco-2 cells, while either AKT or ERK inhibition can prevent SSM-mediated nuclear translocation of Nrf2. Furthermore, SSM displayed a better protective effect against dextran sulfate sodium- (DSS-) induced UC compared with 5-aminosalicylic acid (5-ASA) in C57BL/6 mice. The enhanced Nrf2 signaling and activated AKT/ERK were also observed in the colon of mice after SSM administration. These results first demonstrate the protective effect of SSM against UC and indicate that the effect is associated with AKT/ERK activation and subsequent Nrf2 signaling enhancement. This study provides a new insight into the medicinal value of SSM and proposes it as a new natural nutrition for better managing the symptoms of UC.

Aqueous extract of Dipsacus asperoides suppresses lipopolysaccharide-stimulated inflammatory responses by inhibiting the ERK1/2 signaling pathway in RAW 264.7 macrophages

ETHNOPHARMACOLOGICAL RELEVANCE

Dipsaci Radix, which is the dried root of Dipsacus asperoides C. Y. Cheng and T. M. Ai (Dipsacaceae), is used to treat back pain and blood stasis syndrome in Korean traditional medicine.

AIM OF THE STUDY

To understand the mechanisms responsible for the pharmacological activities of D. asperoides, we investigated the inhibitory effect of D. asperoides on lipopolysaccharide (LPS)-induced inflammation in mouse macrophages RAW 264.7 cells.

MATERIALS AND METHODS

Aqueous extract of D. asperoides (AEDA) was prepared by boiling D. asperoides in water and then administered to LPS treated RAW 264.7 cells. Cell viabilities were measured using an MTT assay, and protein levels were determined by western blotting. The ROS scavenging activity of AEDA was measured using a DCFH-DA assay and levels of nitric oxide (NO) were determined using a NO assay. The nuclear translocations of NF-κB and Nrf2 were investigated immunocytochemically, and pro-inflammatory cytokines in supernatant were evaluated by ELISA.

RESULTS

Treatment with AEDA suppressed the expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in LPS-stimulated RAW 264.7 macrophages. AEDA also reduced ROS, pro-inflammatory cytokine (IL-6 and IL-1β) levels, and iNOS-derived NO and COX-2-derived prostaglandin E2 release to medium, and suppressed the phosphorylation and degradation of IκB and the activation of NF-κB in macrophages. Furthermore, treatment with AEDA inhibited the ERK1/2 pathway but not the JNK or p38 MAPK pathways. In addition, AEDA significantly promoted Nrf2 translocation from cytoplasm to nucleus and up-regulated the expression of HO-1.

CONCLUSION

These results suggest that AEDA has anti-inflammatory and anti-oxidative effects through the inhibition of NF-κB and ERK1/2 and the activation of Nrf2/HO-1 in macrophages.

Enzymatic Extraction, Purification, and Characterization of Polysaccharides from Penthorum chinense Pursh: Natural Antioxidant and Anti-Inflammatory

Penthorum chinense Pursh (PCP) is a kind of functional food or medicine for liver protection. In the present work, Plackett-Burman design, steepest ascent method, and response surface methodology (RSM) were employed to obtain maximum total sugar yield. The experimental yield of 6.91% indicated a close agreement with the predicted yield of 7.00% of the model under optimized conditions. The major polysaccharide fraction (PCPP-1a) from PCPP was purified and identified as acidic polysaccharides with a high content of uronic acid (FT-IR, UV, HPGPC). PCPP had similar monosaccharide profile with PCPP-1a but was rich in galacturonic acid (HPLC). Both of PCPP and PCPP-1a possessed strong hydroxyl radical scavenging, DPPH radical scavenging, and Fe²⁺ chelating activities. Moreover, they were revealed to show strong anti-inflammatory activities by inhibiting NO, TNF-α, and IL-1β release compared to LPS treatment in RAW264.7 cells. These data suggest that the polysaccharides from PCP could be potential natural products for treating ROS and inflammatory-related diseases.