Caffeine prevents LPS-induced inflammatory responses in RAW264.7 cells and zebrafish

Smilax guianensis Vitman Extract Prevents LPS-Induced Inflammation by Inhibiting the NF-κB Pathway in RAW 264.7 Cells

Nutraceutical treatments can reduce inflammation and prevent the development of inflammatory diseases. In this study, the anti-inflammatory effects of Smilax guianensis Vitman extract (SGE) were examined. SGE suppressed lipopolysaccharide (LPS)-mediated nitrite production in RAW 264.7 cells. SGE also prevented the LPS-induced expression of inducible nitric oxide synthase (iNOS) but not cyclooxygenase (COX)-2. Western blot analysis showed that SGE attenuated LPS-induced phosphorylation of IκB kinase (IKK), inhibitor of kappa B (IκB), and p65. Additionally, SGE inhibited LPS-induced IκB degradation in RAW 264.7 cells. Western blot analysis of the cytosolic and nuclear fractions, as well as immunofluorescence assay results, revealed that SGE suppressed LPS-induced p65 nuclear translocation in RAW 264.7 cells. Moreover, SGE reduced LPS-induced interleukin (IL)- 1β, IL-6, and tumor necrosis factor-α (TNF-α) mRNA expression and IL-1β and IL-6 protein expression in RAW 264.7 cells. Collectively, these results indicate that SGE suppresses the NF-κB signaling pathway and thereby inhibits the production of NO, IL-1β, and IL-6.

Phyllolobium chinense Fisch Flavonoids (PCFF) Suppresses the M1 Polarization of LPS-Stimulated RAW264.7 Macrophages by Inhibiting NF-κB/iNOS Signaling Pathway

Background

M1 macrophage plays an important role in inflammatory reaction. In this study, potential anti-inflammatory effect of Phyllolobium chinense Fisch flavonoids (PCFF) was assessed via Zebrafish acute inflammation model in vivo and LPS-induced pro-inflammatory M1 macrophage model in vitro.

Methods

The quality control of P. chinense Fisch flavonoids (PCFF) was analyzed by HPLC. Anti-inflammatory effect of PCFF on the acute injured zebrafish was evaluated by the migration of fluorescence labeled macrophages and neutrophils, and the gene expression of inflammatory factors. In addition, the anti-inflammatory mechanism of PCFF was investigated by the related gene expression and related signaling pathway regulation of pro-inflammatory mediators in LPS-induced pro-inflammatory M1 RAW264.7 macrophage.

Results

P. chinense Fisch flavonoids (PCFF) markedly suppressed macrophage and neutrophil migration and iNOS gene expression in acute injured zebrafish with tail-cutting. PCFF significantly inhibited NO overproduction and iNOS gene overexpression in LPS-sitimulated pro-inflammatory M1 RAW264.7 macrophages. What's more, PCFF could evidently decrease p65 protein production, but had no effect on the production of P38, JNK and ERK1/2 proteins.

Conclusion

P. chinense Fisch flavonoids (PCFF) have a remarkable inhibitory effect on the inflammatory response in acute injured zebrafish and LPS-stimulated M1 RAW264.7 macrophage. The pharmacological mechanism may be related to the regulation of NO overproduction and the inhibition of NF-κB/iNOS signaling pathway.

Ameliorative effects of Magnolia sieboldii buds hexane extract on experimental reflux esophagitis

Gastroesophageal reflux disease (GERD) is a disease that stomach contents continually refluxing into esophagus causes symptoms and/or complications. The study was working to find natural plant extracts with good effects and small side effects to treat reflux esophagitis (RE). The anti-inflammatory effects of hexane extract of Magnolia sieboldii (MsHE) were conducted on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. The ameliorative effects of MsHE on esophageal damage in rats induced by gastric acid reflux was explored in vivo. The results showed that MsHE decreased the production of nitric oxide (NO) and expression levels of iNOS, COX-2 and TNF-α on LPS-stimulated RAW 264.7 cells and MsHE treatment ameliorated the rats' esophageal tissue damage induced by gastric acid and inhibited the increase of inflammatory mediators and pro-inflammatory cytokines by regulating NF-κB signaling pathway. In addition, MsHE protected the function of barrier of epithelial cells against inflammatory conditions through increasing the expression of tight junctions. Furthermore, liquid chromatography-mass spectrometry analysis was used for determine the active ingredients contained in MsHE. The results show that MsHE can alleviate experimental rat RE by regulating NF-κB signaling pathway. In summary, MsHE may be used as a source material of drug candidate for the treatment of RE.

Cortisol inhibits the Escherichia coli-induced endometrial inflammatory response through NF-κB and MAPK pathways in postpartum goats

Glucocorticoids have been widely used as anti-inflammatory therapies. The mechanisms of cortisol action in goat does with endometritis, however, have not been reported. The aim of this study was to investigate the mechanism of cortisol in modulation of effects of E. coli-induced endometritis in the does. Does (n = 24) were assigned to four groups (n = 6): control, E. coli, cortisol, and E. coli + cortisol groups. Does in the cortisol and E. coli + cortisol group were treated with cortisol from 3 days before E. coli inoculations occurred to 36 days post-partum. Does in the E. coli and inoculation groups were administered via intrauterine infusion E. coli O₅₅ (10⁹ CFU/mL) at 0 h. Physical indicators, macroscopic and microscopic changes in the endometrium, uterine secretion cytology and bacteriology were evaluated before (0 h) and at 6, 12, 24, 48, and 72 h after E. coli inoculation. The TLR4 and pro-inflammatory cytokine mRNA transcripts were detected using qPCR. The activations of NF-κB and MAPK signaling pathways were detected using Western blot procedures. As a result, cortisol inhibited the inflammatory response of does by reducing the clinical symptoms, morphological endometrial damage, % PMN in uterine secretions, relative abundance of inflammatory gene mRNA transcripts in the endometrium of does. Cortisol inhibited NF-κB activity by reducing MyD88 and IκB phosphorylation. Treatment with cortisol suppressed the phosphorylation of ERK1/2, p38MAPK, and JNK. These results indicate the anti-inflammatory effect of cortisol in the endometrium of does may be regulated by NF-κB and MAPK pathways.

Paeoniflorin alleviates lipopolysaccharide-induced disseminated intravascular coagulation by inhibiting inflammation and coagulation activation

Lipopolysaccharide (LPS) is a toxic component of the outer membrane of gram-negative bacteria that can activate the blood coagulation system, leading to disseminated intravascular coagulation (DIC). DIC is a syndrome characterized by thromboembolism and multiple organ failure. Herein, the beneficial effect of paeoniflorin (PF) on the alleviation of LPS-induced DIC was investigated with an experimental DIC mouse model. Briefly, mice were randomly divided into the following six groups: (1) control; (2) LPS; (3) heparin; (4) low-PF treatment; (5) medium-PF treatment; and (6) high-PF treatment. The histological morphology of the liver and kidney was observed, and the coagulation indicators (such as prothrombin time), function indicators (such as alanine transferase), and inflammatory factors (such as TNF-α) were detected. Additionally, an in vitro cell inflammation model using RAW 264.7 murine macrophages was established. Activation of the nuclear factor kappa B (NF-κB) signaling pathway and tumor necrosis factor-α (TNF-α) were determined by western blotting. Based on our findings, PF could significantly improve the histological morphology of the liver and kidney, indicating that PF protects the liver and kidney against damage induced by LPS. Additionally, PF improved the function and coagulation indicators and reduced the production of inflammatory factors. In vitro, PF inhibited the expression of TNF-α by suppressing NF-κB signaling pathway activation. Collectively, our findings support the hypothesis that PF has anti-inflammatory and anticoagulation effects for the alleviation of LPS-induced DIC. PF is thus a potential co-treatment option for DIC.

Silicone elastomer gel impregnated with 20(S)-protopanaxadiol-loaded nanostructured lipid carriers for ordered diabetic ulcer recovery

Inefficient diabetic ulcer healing and scar formation remain a challenge worldwide, owing to a series of disordered and dynamic biological events that occur during the process of healing. A functional wound dressing that is capable of promoting ordered diabetic wound recovery is eagerly anticipated. In this study, we designed a silicone elastomer with embedded 20(S)-protopanaxadiol-loaded nanostructured lipid carriers (PPD-NS) to achieve ordered recovery in scarless diabetic ulcer healing. The nanostructured lipid carriers were prepared through an emulsion evaporation-solidification method and then incorporated into a network of silicone elastomer to form a unique nanostructured lipid carrier-enriched gel formulation. Interestingly, the PPD-NS showed excellent in vitro anti-inflammatory and proangiogenic activity. Moreover, in diabetic mice with full-thickness skin excision wound, treatment with PPD-NS significantly promoted in vivo scarless wound healing through suppressing inflammatory infiltration in the inflammatory phase, promoting angiogenesis during the proliferation phase, and regulating collagen deposition in the remodeling phase. Hence, this study demonstrates that the developed PPD-NS could facilitate ordered diabetic wound recovery via multifunctional improvement during different wound-healing phases. This novel approach could be promising for scarless diabetic wound healing.

Deacetyl Ganoderic Acid F Inhibits LPS-Induced Neural Inflammation via NF-κB Pathway Both In Vitro and In Vivo

Microglia mediated neuronal inflammation has been widely reported to be responsible for neurodegenerative disease. Deacetyl ganoderic acid F (DeGA F) is a triterpenoid isolated from Ganoderma lucidum, which is a famous edible and medicinal mushroom used for treatment of dizziness and insomnia in traditional medicine for a long time. In this study the inhibitory effects and mechanisms of DeGA F against lipopolysaccharide (LPS)-induced inflammation both in vitro and in vivo were investigated. On murine microglial cell line BV-2 cells, DeGA F treatment inhibited LPS-triggered NO production and iNOS expression and affected the secretion and mRNA levels of relative inflammatory cytokines. DeGA F inhibited LPS-induced activation of the NF-κB pathway, as evidenced by decreased phosphorylation of IKK and IκB and the nuclear translocation of P65. In vivo, DeGA F treatment effectively inhibited NO production in zebrafish embryos. Moreover, DeGA F suppressed the serum levels of pro-inflammatory cytokines, including TNF-α and IL-6 in LPS-stimulated mice model. DeGA F reduced inflammatory response by suppressing microglia and astrocytes activation and also suppressed LPS-induced NF-κB activation in mice brains. Taken together, DeGA F exhibited remarkable anti-inflammatory effects and promising therapeutic potential for neural inflammation associated diseases.

The protection of indolealkylamines from LPS-induced inflammation in zebrafish

ETHNOPHARMACOLOGICAL RELEVANCE

Toad skin came from Bufo bufo gargarizans Cantor and Bufo melanostictus Schneider. As the traditional Chinese medicine, it had the effect of clearing away heat and detoxification. In traditional applications, toad skin was often used for the treatment of cancer and inflammation. Total indolealkylamines (IAAs) from this medicine were proved the main compounds exert anti-inflammatory activity in our previous research.

AIM OF THE STUDY

In the present study, we aimed to investigate the potential mechanism of anti-inflammatory activity of IAAs on LPS induced zebrafish.

MATERIALS AND METHODS

LPS induced zebrafish was applicated as an in vivo inflammation model to clarify the structure-activity relationship of 4 major IAAs (N-methyl serotonin, bufotenine, dehydrobufotenine and bufothionine) from toad skin. Quantitative RT-PCR was applied to detect key cytokines and members of the MyD88-dependent signaling pathway. In addition, the targeted lipidomics was conducted to find out the potential biomarkers in the inflammatory zebrafish. Network pharmacology was used to unveil the main enzymes closely related to the target lipids.

RESULTS

Our results showed that the anti-inflammatory activity of free IAAs (N-methyl serotonin, bufotenine and dehydrobufotenine) was more potent than that of combined IAAs (bufothionine). RT-PCR demonstrated that 4 IAAs exerted antiendotoxin inflammatory effect via suppressing the TLR4/MyD88/NF-κB and TLR4/MyD88/MAPKs signaling pathway. A total of 33 possible inflammatory biomarkers, including 14 SM, 6 Cer, 11 PC and 2 GlcCer, triggered by LPS were screened out. The levels of most of candidates could be regulated toward a normal level by IAAs, especially in N-methyl serotonin and dehydrobufotenine groups. Enzymes especially LBP, PLA₂, CERK, SMPD and SGMS were found closely associated with the regulation of most lipid markers.

CONCLUSIONS

Overall, the mechanism underlying the anti-inflammatory activity of IAAs probably attributed to their capability to suppress NF-κB and MAPKs inflammatory pathway. Meanwhile, IAAs could also interfere the metabolism of SM, Cer and PC probably by regulating LBP, PLA₂, CERK, SMPD and SGMS.

Anti-inflammatory and Regulatory Effects of Huanglian Jiedu Decoction on Lipid Homeostasis and the TLR4/MyD88 Signaling Pathway in LPS-Induced Zebrafish

Huanglian Jiedu decoction (HLJDD) has been used in the clinical treatment of inflammatory conditions. To clarify the mechanism of its comprehensive anti-inflammatory activities, the correlation between lipid homeostasis and the TLR4/MyD88 signaling pathway in zebrafish was established in the present study. In the lipopolysaccharide (LPS)-induced inflammation in zebrafish model, RT-PCR assays of five inflammatory cytokines and six targeted proteins were measured. Lipidomics analysis was conducted to identify potential lipid markers. HLJDD displayed strong efficacies, with a 61% anti-inflammatory rate at a concentration of 50 μg/mL. The activation of TLR4/MyD88 played an essential role in the inflammatory process. All protein indexes in the HLJDD group exhibited a tendency to reverse back to normal levels. Moreover, 79 potential pathological lipid biomarkers were identified. Compared with the model group, 61 therapeutic lipid biomarkers were detected in HLJDD group. Most perturbations of lipids were ameliorated by HLJDD, mainly through the glycerophospholipid metabolic pathway. In the visual network study, the corresponding lipoproteins such as PLA2, SGMS, and SMDP were observed as important intermediates between lipid homeostasis and the TLR4/MyD88 signaling pathway.

Relationship of the Phytochemicals from Coffee and Cocoa By-Products with their Potential to Modulate Biomarkers of Metabolic Syndrome In Vitro

This study aimed to compare the phytochemicals from coffee and cocoa by-products and their relationship with the potential for reducing markers of inflammation, oxidative stress, adipogenesis, and insulin resistance in vitro. We characterized the phytochemical profile of extracts from coffee husk, coffee silverskin, and cocoa shell and evaluated their in vitro biological activity in RAW264.7 macrophages and 3T3-L1 adipocytes. Pearson correlations and principal component regressions were performed to find the contribution of phytochemicals and underlying mechanisms of action. Coffee husk and silverskin extracts were mainly composed of caffeine and chlorogenic acid. Major components in cocoa shell included theobromine and protocatechuic acid. Both coffee and cocoa by-product extracts effectively reduced inflammatory markers in macrophages and adipocytes (NO, PGE2, TNF-α, MCP-1, and IL-6) and the production of reactive oxygen species (21.5-66.4%). Protocatechuic and chlorogenic acids, together with caffeine, were suggested as main contributors against inflammation and oxidative stress. Furthermore, extracts reduced lipid accumulation (4.1-49.1%) in adipocytes by regulating lipolysis and inducing adipocyte browning. Gallic and chlorogenic acids were associated with reduced adipogenesis, and caffeine with adipocyte browning. Extracts from coffee and cocoa by-products also modulated the phosphorylation of insulin receptor signaling pathway and stimulated GLUT-4 translocation (52.4-72.9%), increasing glucose uptake. The insulin-sensitizing potential of the extracts was mainly associated with protocatechuic acid. For the first time, we identified the phytochemicals from coffee and cocoa by-products and offered new insights into their associations with biomarkers of inflammation, oxidative stress, adipogenesis, and insulin resistance in vitro.

ERK1/2 mediates the lipopolysaccharide-induced upregulation of FGF-2, uPA, MMP-2, MMP-9 and cellular migration in cardiac fibroblasts

Myocardial fibrosis is a critical event during septic shock. Upregulation in the fibrosis signaling cascade proteins such as fibroblast growth factor (FGF), urokinase plasminogen activator (uPA), tissue plasminogen activator (tPA) and activation of matrix metalloproteinases (MMPs) are widely associated with the development of myocardial infarction, dilated cardiomyopathy, cardiac fibrosis and heart failure. However, evidences suggest that the common upstream mediators of fibrosis cascade play little role in cardiac fibrosis induced by LPS; further, it is unknown if LPS directly triggers the expressions and/or activity of FGF-2, uPA, tPA, MMP-2 and MMP-9 in cardiac fibroblasts. In the present study, we treated primary cultures of cardiac fibroblasts with LPS to explore whether LPS upregulates FGF-2, uPA, tPA, MMP-2, MMP-9 and enhance cellular migration. Further the precise molecular and cellular mechanisms behind these LPS induced responses were identified. Inhibition assays on MAPKs using U0126 (ERK1/2 inhibitor), SB203580 (p38 MAPK inhibitor), SP600125 (JNK1/2 inhibitor), CsA (calcineurin inhibitor) and QNZ (NFκB inhibitor) show that LPS-induced upregulation of FGF-2, uPA, MMP-2 and MMP-9 in cardiac fibroblasts was mediated through ERK1/2 signaling. Collectively, our results provide a link between LPS-induced cardiac dysfunction and ERK1/2 signaling pathway and thereby implies ERK1/2 as a possible target to regulate LPS induced upregulation of FGF-2, uPA, MMP-2, MMP-9 and cellular migration in cardiac fibroblasts.

Esculentoside B inhibits inflammatory response through JNK and downstream NF-κB signaling pathway in LPS-triggered murine macrophage RAW 264.7 cells

Natural compound esculentoside B (EsB), (2S,4aR,6aR,6aS,6bR,8aR,9R,10R,11S,12aR,14bS)-11-hydroxy-9-(hydroxymethyl)-2 methoxycarbonyl-2,6a,6b,9,12a-pentamethyl-10-[(2S,3R,4S,5R)-3,4,5-trihydroxyoxan-2-yl]oxy-1,3,4,5,6,6a,7,8,8a,10,11,12,13,14b-tetradecahydropicene-4a-carboxylic acid with molecular weight of 664.833, isolated from roots of Phytolacca acinosa Roxb has been widely used as a constituent of traditional Chinese medicine (TCM). However, the anti-inflammatory capacity of EsB has not been reported yet. Therefore, the objective of this study was to investigate anti-inflammatory activities of EsB in LPS-treated macrophage RAW 264.7 cells. EsB could inhibit nitric oxide (NO) production. EsB also suppressed gene and protein expression levels of inducible isoform of NO synthase (NOS) and cyclooxygenase-2 in a dose-dependent manner. In addition, EsB decreased gene expression and protein secretion levels of pro-inflammatory cytokines such as IL-1β, TNF-α, and IL-6. EsB remarkably suppressed nuclear translocation of nuclear factor kappa-B (NF-κB) from cytosolic space. Phosphorylation of IκB was also inhibited by EsB. Moreover, EsB specifically down-regulated phospho-c-Jun N-terminal kinase (p-JNK), but not p-p38 or phospho-extracellular signal-regulated kinase 1/2 (p-ERK1/2). Taken together, these results suggest that EsB has inhibitory effect on inflammatory response by inactivating NF-κB and p-JNK. It could be used as a new modulatory drug for effective treatment of inflammation-related diseases.

Comparative Analysis of Hydrophilic Ingredients in Toad Skin and Toad Venom Using the UHPLC-HR-MS/MS and UPLC-QqQ-MS/MS Methods Together with the Anti-Inflammatory Evaluation of Indolealkylamines

Toad skin and toad venom, as two kinds of Chinese medicine, are prepared from Bufo bufo gargarizans Cantor and Bufo melanostictus Schneider. However, they display distinct properties in traditional application, and the hydrophilic ingredients are the possible distinguishing chemicals between them. In this work, 36 and 22 hydrophilic components were characterized from toad skin and venom, respectively, by UHPLC-HR-MS/MS, including amino acids, nucleosides, polypeptides, and indolealkylamines (IAAs). Among them, 15 compounds were unambiguously confirmed by comparison with standards. The CID-MS/MS fragmentation behaviors of seven indolealkylamine references were investigated to ascertain three types of structures. Subsequently, 11 high abundance contents of hydrophilic ingredients were determined from 11 batches of toad skin and 4 batches of toad venom by UPLC-QqQ-MS/MS. The quantitative results showed that the content of main IAAs in toad venom was much higher than in skin. In addition, the N-methyl serotonin (free IAA), bufothionine (combined IAA), and total IAAs sample were selected for anti-inflammatory evaluation in lipopolysaccharide (LPS) stimulated zebrafish embryo models. The obvious anti-inflammatory activities of IAAs were observed, especially for the free IAAs. This study illustrated IAAs were the main distinct hydrophilic components that probably lead to the difference between toad skin and toad venom in traditional applications.

Anti-Inflammatory Effects of Aurantio-Obtusin from Seed of Cassia obtusifolia L. through Modulation of the NF-κB Pathway

Aurantio-obtusin, an anthraquinone compound, isolated from dried seeds of Cassia obtusifolia L. (syn. Senna obtusifolia; Fabaceae) and Cassia tora L. (syn. Senna tora). Although the biological activities of Semen Cassiae have been reported, the anti-inflammatory mechanism of aurantio-obtusin, its main compound, on RAW264.7 cells, remained unknown. We investigated the anti-inflammatory effect of aurantio-obtusin on lipopolysaccharide- (LPS)-induced RAW264.7 cells in vitro and elucidated the possible underlying molecular mechanisms. Nitric oxide production (NO) and prostaglandin E₂ (PGE₂) were measured by the Griess colorimetric method and enzyme-linked immunosorbent assay (ELISA), respectively. Protein expression levels of cyclooxygenase 2 (COX-2) were monitored by cell-based ELISA. Interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF-α) synthesis were analyzed using ELISA. The mRNA expression of nitric oxide synthase (iNOS), COX-2, and the critical pro-inflammatory cytokines (IL-6 and TNF-α) were detected by quantitative real-time PCR. Aurantio-obtusin significantly decreased the production of NO, PGE₂, and inhibited the protein expression of COX-2, TNF-α and IL-6, which were similar to those gene expression of iNOS, COX-2, TNF-α and IL-6 (p < 0.01). Consistent with the pro-inflammatory gene expression, the Aurantio-obtusin efficiently reduced the LPS-induced activation of nuclear factor-κB in RAW264.7 cells. These results suggested that aurantio-obtusin may function as a therapeutic agent and can be considered in the further development of treatments for a variety of inflammatory diseases. Further studies may provide scientific evidence for the use of aurantio-obstusin as a new therapeutic agent for inflammation-related diseases.

An Ethanolic Extract of Allium hookeri Root Alleviates Reflux Esophagitis and Modulates NF-κB Signaling

Reflux esophagitis (RE) is a kind of gastroesophageal reflux disease, of which an esophageal inflammatory lesion is caused by the contents of the stomach and duodenum flowing back into the esophagus. Allium hookeri is a plant possessing both nutritional and medicinal properties. In our study, we investigated the inhibition effect of inflammation of A. hookeri root extract (AHE) on inflammatory RAW264.7 macrophage cells induced by lipopolysaccharide and rat models of RE. The results showed that AHE significantly reduced the production of nitric oxide (NO) and the protein expression levels of various mediators related to inflammation including inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and inflammatory cytokines such as interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α). Furthermore, AHE also inhibited the nuclear translocation of nuclear factor kappa B (NF-κB) by inhibiting the phosphorylation IκBα. In addition, AHE administration significantly ameliorated esophageal mucosal damage upon histological evaluation of RE in rats. AHE was also found to downregulate the expression levels of proteins such as COX-2, TNF-α, and IL-1β in the rat esophagus. AHE markedly attenuated activation of NF-κB and phosphorylation of IκBα at the same time. These results indicated that AHE suppressed LPS-induced inflammatory responses in RAW264.7 cells and may help reduce the development of esophagitis through the modulation of inflammation by regulating NF-κB activation.

Caffeine: Well-known as psychotropic substance, but little as immunomodulator

To date, numerable reviews are found in the literature prominent to the effect of caffeine on the immune system, with the latest review published in 2006. Database screening reveals around three thousand articles that have been published during the last decade. Interestingly, less than hundred articles involved humans and rodents as tested models, out of which 20% is of interest to this paper excluding studies done on the nervous and cardiac systems, and in pregnant and cancer cases. In this review, information pertaining to the experimental setup of various studies, namely, the tested model, the study type (in vivo or in vitro), and caffeine dose is covered to discern the behaviour of major cellular and molecular immune components in light of caffeine exposure. Although it is hard to extrapolate results done in rodents to humans and to relay conclusions from in vitro to in vivo studies, most of the collected data favor the suppressive effects of caffeine on the proliferation of stimulated lymphocytes. Macrophages and natural killer cells also exhibited a reduced activity in the presence of high caffeine doses compared to increased activity at low doses. Immunosuppression is also supported by reduced levels of major anti-inflammatory cytokines, IL-2, IL-6, TNF-α. Moreover, certain innate and adaptive immune receptors, such as TLR1, TLR2, TLR4, and MHC class I-related chain B (MICB) molecules, exhibited decreased expression levels. Thus, we support the use of caffeine to alleviate various inflammatory conditions and autoimmune diseases.

Protective effect of polysaccharides from Celluclast-assisted extract of Hizikia fusiforme against hydrogen peroxide-induced oxidative stress in vitro in Vero cells and in vivo in zebrafish

Polysaccharides were extracted by Celluclast-assisted hydrolysis and ethanol precipitation from Hizikia fusiforme (HFPS), and their in vitro antioxidant effects were evaluated in Vero cells. HFPS contains 63.56±0.32% sulfate polysaccharides, which comprise fucose (53.53%), galactose (23.15%), glucose (5.95%), and xylose (17.37%). HFPS scavenged DPPH, alkyl, and hydroxyl radicals at IC50 values of 0.81±0.02, 0.25±0.02, and 0.21±0.03mg/mL, respectively. HFPS significantly reduced H2O2-induced cytotoxicity in Vero cells. Furthermore, HFPS reduced intracellular ROS levels, and H2O2-induced apoptosis. HFPS has a strong protective effect against H2O2-stimulated oxidative stress in vivo in zebrafish, and showed improved survival rate, decreased heart rate, and reduced ROS generation and cell death. These results suggest that HFPS may be useful as an antioxidant in medical and cosmetic industries.

Psychoneuroimmunology and immunopsychiatry of zebrafish

Despite the high prevalence of neural and immune disorders, their etiology and molecular mechanisms remain poorly understood. As the zebrafish (Danio rerio) is increasingly utilized as a powerful model organism in biomedical research, mounting evidence suggests these fish as a useful tool to study neural and immune mechanisms and their interplay. Here, we discuss zebrafish neuro-immune mechanisms and their pharmacological and genetic modulation, the effect of stress on cytokines, as well as relevant models of microbiota-brain interplay. As many human brain diseases are based on complex interplay between the neural and the immune system, here we discuss zebrafish models, as well as recent successes and challenges, in this rapidly expanding field. We particularly emphasize the growing utility of zebrafish models in translational immunopsychiatry research, as they improve our understanding of pathogenetic neuro-immune interactions, thereby fostering future discovery of potential therapeutic agents.

Effects of Coffee Extracts with Different Roasting Degrees on Antioxidant and Anti-Inflammatory Systems in Mice

Coffee roasting affects the taste, color, and aroma of coffee. The Maillard reaction, a major reaction during the roasting process, produces melanoidin, which affects the overall antioxidant capacity and anti-inflammatory effects of coffee. In this experiment, coffee roasting was divided into four degrees: Light, Medium, City, and French. To examine the in vivo antioxidant and anti-inflammatory effects of coffee extracts with different roasting degrees, we used 10-week-old male C57BL/6 mice. Mice were pre-treated with coffee extracts for 10 days by oral gavage (300 mg/Kg.B.W). After the last pre-treatment, lipopolysaccharide (LPS, 15 mg/Kg.B.W) was injected intraperitoneally for immune stimulation. Histopathological analysis showed that hepatic portal vein invasion and liver necrosis were severe in the LPS-treated group. However, these phenomena were greatly ameliorated when mice were pre-treated with Light- or Medium-roasted coffee extracts. Hepatic glutathione level was increased in the French group but decreased in the LPS-stimulated group. When mice were treated with LPS, mRNA expression level of tumor necrosis factor-alpha (TNF-α) was increased, whereas TNF-α expression was significantly reduced in the Light and Medium groups. Treatment with coffee extracts decreased the mRNA expression levels of interleukin 6 (IL-6) in mice stimulated by LPS, regardless of coffee roasting degrees. These effects decreased with the increasing coffee roasting degree. Results of luciferase reporter assay revealed that these effects of coffee extracts were transcriptionally regulated by the NF-κB pathway. Taken together, these results suggest that the roasting degree affects the antioxidant and anti-inflammatory effects of coffee extracts.

Oral administration of Lentinus edodes β-glucans ameliorates DSS-induced ulcerative colitis in mice via MAPK-Elk-1 and MAPK-PPARγ pathways

To evaluate the anti-inflammatory effect of β-glucans from Lentinus edodes, and its molecular mechanism, the dextran sulfate sodium salt (DSS) induced colitis model of mice and the LPS-stimulated RAW264.7 cell inflammation model were used in this study. 40 ICR male mice were randomly divided into 4 groups: Control, DSS (DSS treated only), DSS + low-βGs (500 mg kg^-1 d^-1) and DSS + high-βGs (1000 mg kg^-1 d^-1). The body weight of the mice with Lentinus edodes β-glucan supplementation increased significantly compared to the DSS group and the disease activity index (DAI) was improved in both βG-treated groups. Compared with the DSS group, histopathological analysis showed that the infiltration of inflammatory cells of both βG-treated groups decreased significantly in colonic tissues. Furthermore, oral administration of β-glucans decreases the concentration of malondialdehyde (MDA) and myeloperoxidase (MPO) and inhibits the expression of iNOS and several inflammatory factors: TNF-α, IL-1β and IL-6 as well as nitric oxide (NO) of the colonic tissues. The mitogen-activated protein kinase (MAPK) pathway is closely related to the expression of pro-inflammatory factors. In the DSS-induced colitis model and the LPS-stimulated RAW264.7 cell model, βGs inhibited the expression of pro-inflammatory factors and blocked the phosphorylation of JNK/ERK1/2 and p38; βGs also suppress the phosphorylation of Elk-1 at Ser84 and the phosphorylation of PPARγ at Ser112. Altogether, these results suggest that Lentinus edodes βGs could inhibit the DSS-induced ulcerative colitis and decrease inflammatory factor expressions. The molecular mechanism may be involved in suppressing MAPK signaling and inactivation of Elk-1 and activation of PPARγ.

Enzymatic extract from Ecklonia cava: Acute and subchronic oral toxicity and genotoxicity studies

Ecklonia cava (EC) is known to have antioxidant, anti-inflammatory, antidiabetic, and anticancer properties. Despite its wide use and beneficial properties, comprehensive toxicological information regarding EC extract is currently limited. Therefore, the purpose of this study was to investigate acute toxicity, subchronic toxicity, and genotoxicity of enzymatic EC extract according to test guidelines published by Organization for Economic Cooperation and Development. The acute oral LD50 values of this EC extract administered to rats and dogs were estimated to be more than 3000 mg/kg BW. In an oral 13-week toxicity study, changes in body weights of rats exposed to the EC extract up to 3000 mg/kg BW were found to be normal. In addition, repeated doses of EC extract failed to influence any systematic parameters of treatment-related toxic symptoms such as food/water consumption, mortality, urinalysis, hematology, serum biochemistry, organ weight, or histopathology. These results indicated that the no-observed-adverse-effect level for the EC extract was 3000 mg/kg/day for male and female rats. Data obtained from Ames test, chromosome aberration assay, and micronucleus assay indicated that EC extract was not mutagenic or clastogenic. Taken together, these results support the safety of enzymatic EC extract as a potential therapeutic for human consumption against various diseases.

Cortisol modulates inflammatory responses in LPS-stimulated RAW264.7 cells via the NF-κB and MAPK pathways

Background

The uteruses of most dairy cattle are easily infected by bacteria, especially gram-negative bacteria, following parturition. Macrophages are important cells of the immune system and play a critical role in the inflammatory response. In addition, cortisol levels become significantly increased due to the stress of parturition in dairy cattle, and cortisol is among the most widely used and effective therapies for many inflammatory diseases. In this study, we assessed the anti-inflammatory effects and potential molecular mechanisms of cortisol using a Lipopolysaccharide (LPS)-induced RAW264.7 macrophage cell line.

Results

Cortisol significantly suppressed the production of prostaglandin E₂ (PGE₂) and decreased the gene and protein expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) in a dose-dependent manner. Moreover, cortisol inhibited the mRNA expression of pro-inflammatory cytokines including tumor necrosis factor alpha (TNFα), interleukin-1β (IL-1β), and interleukin-6 (IL-6) and decreased IL-1β secretion in an LPS-treated RAW264.7 macrophage cell line. Moreover, we found that cortisol suppressed nuclear factor-kappa B (NF-κB) signaling in RAW264.7 macrophages stimulated with LPS. This suppression was mediated by the inhibition of IκBα degradation and NF-κB p65 phosphorylation. In addition, cortisol also suppressed the phosphorylation of mitogen-activated protein kinases (MAPK) such as extracellular signal-regulated kinase (ERK1/2), p38 MAPK, and c-Jun N-terminal kinase/stress-activated protein kinase (JNK).

Conclusions

These results suggest that high cortisol levels can attenuate LPS-induced inflammatory responses in the RAW264.7 macrophage cell line by regulating the NF-κB and MAPK signaling pathways.

Cortisol inhibits NF-κB and MAPK pathways in LPS activated bovine endometrial epithelial cells

The bovine uterus is subject to infection after calving, which may lead to endometritis. Elevated cortisol levels have been observed in postpartum cattle. However, the role of cortisol in the inflammatory response of the uterus has not been reported. The aim of this study was to investigate the anti-inflammatory effects of cortisol on lipopolysaccharide (LPS)-induced primary bovine endometrial epithelial cells (BEECs). BEECs were treated with various concentrations of cortisol (5, 15 and 30 ng/mL) in the presence of LPS. The mRNA expression of TLR4 and proinflammatory cytokines was measured with qPCR. The activation of NF-κB and MAPK signalling pathways was detected with Western blotting and immunofluorescence. Cortisol induced the down-regulation of the mRNA expression of toll-like receptor 4 (TLR4) and proinflammatory cytokines, including interleukin (IL)-1β, IL-6, IL-8, tumour necrosis factor-α (TNF-α), cyclooxygenase-2 (COX-2) and inducible NO synthase (iNOS). Cortisol inhibited the activity of nuclear factor-κB (NF-κB) via blocking the phosphorylation and degradation of IκB. Cortisol suppressed the phosphorylation of mitogen-activated protein kinase (MAPK), including extracellular signal-regulated kinase (ERK1/2), p38MAPK and c-Jun N-terminal kinase/stress-activated protein kinase (JNK). These results demonstrated that cortisol may exert its anti-inflammatory actions by regulating NF-κB activation and MAPK phosphorylation.

Phytochemicals, Anti-Inflammatory, Antiproliferative, and Methylglyoxal Trapping Properties of Zijuan Tea

Zijuan tea (Camellia sinensis var. assamica) is a unique anthocyanin-rich tea cultivar in China. Although chemical component analysis of Zijuan tea and extraction technology of anthocyanins was widely documented, its functional properties have not been extensively explored. In this study, the anti-inflammatory, antiproliferative, and methylglyoxal (MGO) trapping activities of water extract (ZWE) and ethyl acetate extract (ZEE) of Zijuan tea were investigated for the 1st time. Results showed that ZWE and ZEE exhibited inhibitory effects on nitric oxide (NO), tumor necrosis factor (TNF)-α, and interleukin (IL)-6 production as well as inducible nitric oxide synthase protein (iNOS) expression in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Moreover, Zijuan tea extracts exerted stronger antiproliferative activity against HCT-116 cells compared with HepG2 and MDA-MB-231 cells, and thus could induce apoptosis in HCT-116 cells in a dose-dependent manner. Furthermore, Zijuan tea extracts were effective in trapping MGO under simulated physiological conditions, and the T_1/2 (the time for 50% MGO remaining) values of ZWE and ZEE were 3.69 and 6.20 min, respectively. Additionally, the contents of total phenolics and catechins in ZEE were 685.43 ± 16.00 and 454.96 ± 4.21 mg/g extract, respectively, and in ZWE were 422.59 ± 12.09 and 307.29 ± 0.85 mg/g extract, respectively. Therefore, ZEE exhibited better anti-inflammatory, antiproliferative, and MGO trapping properties than ZWE may be mainly attributed to its higher (P < 0.05) content of total phenolics, expecially catechins. These results suggest that Zijuan tea could be a potential natural resource for the development of functional tea beverage.

PRACTICAL APPLICATION

This study revealed that Zijuan tea extracts possessed anti-inflammatory, antiproliferative, and methylglyoxal trapping potentials in vitro. With high anthocyanins and polyphenols, Zijuan tea can be developed into a healthy tea beverage or used as a natural component to reduce the level of methylglyoxal in Maillard reaction.

SAXS characterization of the interactions among digested food compounds and the anti-oxidant and anti-inflammatory activities of the formed nanocomplexes

Small angle X-ray scattering (SAXS) is applied to investigate the interaction between caseinophosphopeptides (CPP) and chitosan (CS) under simulated gastrointestinal (GI) pH conditions.

Crude Ecklonia cava Flake Extracts Attenuate Inflammation through the Regulation of TLR4 Signaling Pathway in LPS-Induced RAW264.7 Cells

We investigated the beneficial effects of the crude Ecklonia cava flake (CEF), which is a residual product after polyphenol extraction from Ecklonia cava, on inflammation in LPS-stimulated RAW264.7 cells. A group of five different CEF extracts was obtained by a preparation process using water, hydrochloric acid or temperature. We observed that large-size (>19 kDa) CEF extract, which was extracted with water at 95 °C (CEF-W, 95 °C), suppressed the production of inflammatory cytokines by inhibiting its mRNA expression in LPS-induced RAW264.7 cells. TLR4 signaling involvements were negatively regulated by CEF-W, 95 °C. CEF-W, 95 °C repressed the translocation of NF-κB from cytoplasm into nucleus in LPS-induced RAW264.7 cells. CEF-W, 95 °C attenuated the phosphorylation of TBK1 and IRF3 by inhibiting the phosphorylation of ERK. Taken together, we demonstrated that large-size CEF-W, 95 °C may act as a negative regulator of inflammation through the suppression of TLR4 signaling constituents in LPS-induced RAW264.7 cells.

Effect of Coffee in Lipopolysaccharide-Induced Indoleamine 2,3-Dioxygenase Activation and Depressive-like Behavior in Mice

Research has identified a potential inverse correlation between coffee consumption and the risk of depression. The aim of this study was to investigate the effects of caffeinated coffee on lipopolysaccharide-induced depressive-like behaviors and inflammatory biomarkers in an in vivo model of depression in a C57BL/6J mouse model. The behavioral studies showed that caffeinated coffee decreased immobility time in both the tail suspension test (caffeinated coffee 56.60 ± 9.17; p < 0.0001) and the forced swimming test (caffeinated coffee 28.80 ± 5.93; p < 0.0001), suggesting antidepressant-like activity. The effects of caffeinated coffee on the inflammatory biomarkers associated with depression supported the results observed in the behavioral studies. Statistically significant decreases in indoleamine 2,3-dioxygenase activity (p < 0.001) and the neopterin/biopterin ratio (p < 0.001) were observed in animals pretreated with caffeinated coffee 24 h post-lipopolysaccharide exposure in comparison to the lipopolysaccharide control group. In conclusion, this study has provided evidence to suggest that caffeinated coffee has antidepressant-like activities; however, further studies are required to fully investigate these effects.