Selenium-dependent metabolic reprogramming during inflammation and resolution.

Trace element selenium (Se) is incorporated as the 21st amino acid, selenocysteine, into selenoproteins through tRNA[Ser]Sec. Selenoproteins act as gatekeepers of redox homeostasis and modulate immune function to effect anti-inflammation and resolution. However, mechanistic underpinnings involving metabolic reprogramming during inflammation and resolution remain poorly understood. Bacterial endotoxin lipopolysaccharide (LPS) activation of murine bone marrow-derived macrophages cultured in the presence or absence of Se (as selenite) was used to examine temporal changes in the proteome and metabolome by multiplexed tandem mass tag-quantitative proteomics, metabolomics, and machine-learning approaches. Kinetic deltagram and clustering analysis indicated that addition of Se led to extensive reprogramming of cellular metabolism upon stimulation with LPS enhancing the pentose phosphate pathway, tricarboxylic acid cycle, and oxidative phosphorylation, to aid in the phenotypic transition toward alternatively activated macrophages, synonymous with resolution of inflammation. Remodeling of metabolic pathways and consequent metabolic adaptation toward proresolving phenotypes began with Se treatment at 0 h and became most prominent around 8 h after LPS stimulation that included succinate dehydrogenase complex, pyruvate kinase, and sedoheptulokinase. Se-dependent modulation of these pathways predisposed bone marrow-derived macrophages to preferentially increase oxidative phosphorylation to efficiently regulate inflammation and its timely resolution. The use of macrophages lacking selenoproteins indicated that all three metabolic nodes were sensitive to selenoproteome expression. Furthermore, inhibition of succinate dehydrogenase complex with dimethylmalonate affected the proresolving effects of Se by increasing the resolution interval in a murine peritonitis model. In summary, our studies provide novel insights into the role of cellular Se via metabolic reprograming to facilitate anti-inflammation and proresolution.

Oligosaccharides from Polygonatum Cyrtonema Hua: Structural characterization and treatment of LPS-induced peritonitis in mice.

Fructooligosaccharide was isolated from Polygonatum Cyrtonema Hua (PFOS) for the first time. Structure characterized using FT-IR, MALDI-TOF-MS, NMR, AFM, and TEM, indicated that PFOS was graminan-type fructan with a degree of polymerization ranging from 5 to 10. A murine model of lipopolysaccharide (LPS)-induced peritonitis was used to evaluate the in vivo anti-inflammatory and lung protective efficacy of PFOS. The result shown that pretreatment with PFOS (1.0 mg/mL) in peritonitis-induced mice could significantly inhibit the level of pro-inflammatory cytokines (TNF-α, IL-1ß) in serum (P < 0.001), increase mice survival rate from 12.5 % to 54 % (P < 0.05), and alleviated lung injury through ameliorating the damage of the pulmonary cellular architecture and reducing inflammatory monocyte accumulation in lung tissue. This effect of oligosaccharides could explain the traditional usage of P. cyrtonema as a tonic medicine for respiratory problems and it could be used as a potential natural ingredient with anti-inflammatory activity.

Acupuncture reduces peripheral and brainstem cytokines in rats subjected to lipopolysaccharide-induced inflammation.

BACKGROUND: Lipopolysaccharide (LPS) endotoxins are activators of innate immunity inducing infection and inflammatory responses. Anti-inflammatory drugs can have undesirable side effects. Acupuncture may be an alternative for the treatment of inflammatory processes. OBJECTIVE: We investigated the potential anti-inflammatory effect of manual acupuncture (MA) at SP6 upon LPS-induced peritonitis in rats. METHODS: Peritonitis was induced in rats with an intraperitoneal injection of LPS (0.002, 0.02, 0.2 or 2 µg/kg) in four experimental groups (n = 6 each). A fifth group was injected with sterile saline solution (saline group, n = 6). Four hours after the procedure, peritoneal fluid was collected to determine total cell counts for inflammatory cells, differential leukocyte counts and peritoneal capillary permeability. The LPS dose of 0.02 µg/kg was used in the subsequent experiments as it most successfully induced peritoneal inflammation. Subsequently, five experimental groups (n = 12 rats each) were used: (1) saline, (2) control (untreated LPS group), (3) indomethacin (LPS group treated with indomethacin), (4) NA (LPS group treated with MA at a location not corresponding to any traditional acupuncture point), and (5) SP6 (LPS group treated with verum MA at SP6). Ten minutes after MA or 30 min after indomethacin treatment, the rats received an intraperitoneal injection of LPS. After 4 h, total leukocyte and differential cell counts, myeloperoxidase (MPO) activity, vascular permeability and cytokine levels were evaluated in the peritoneal fluid. Cytokine levels were additionally evaluated in the brainstem. RESULTS: SP6 MA and indomethacin treatments reduced inflammatory cell infiltration, vascular permeability and MPO activity in the LPS-exposed rats. Pre-treatment with indomethacin and SP6 MA decreased tumor necrosis factor (TNF)-α levels and preserved interleukin (IL)-10 in the peritoneal fluid. Indomethacin also reduced IL-6 in the peritoneal fluid. In the brainstem, indomethacin reduced IL-1ß, IL-6, TNFα and IL-10, whereas SP6 MA reduced only TNFα and IL-6 levels. CONCLUSIONS: This study clearly demonstrates the anti-inflammatory effect of acupuncture, which we believe may involve the activation of anti-inflammatory neural reflexes in the regulation of peritonitis.

Anti-Inflammatory and Proresolving Effects of the Omega-6 Polyunsaturated Fatty Acid Adrenic Acid.

Polyunsaturated fatty acids (PUFAs) and their metabolites are potent regulators of inflammation. Generally, omega (n)-3 PUFAs are considered proresolving whereas n-6 PUFAs are classified as proinflammatory. In this study, we characterized the inflammatory response in murine peritonitis and unexpectedly found the accumulation of adrenic acid (AdA), a poorly studied n-6 PUFA. Functional studies revealed that AdA potently inhibited the formation of the chemoattractant leukotriene B4 (LTB4), specifically in human neutrophils, and this correlated with a reduction of its precursor arachidonic acid (AA) in free form. AdA exposure in human monocyte-derived macrophages enhanced efferocytosis of apoptotic human neutrophils. In vivo, AdA treatment significantly alleviated arthritis in an LTB4-dependent murine arthritis model. Our findings are, to our knowledge, the first to indicate that the n-6 fatty acid AdA effectively blocks production of LTB4 by neutrophils and could play a role in resolution of inflammation in vivo.

Intraperitoneal Phototherapy Suppresses Inflammatory Reactions in a Surgical Model of Peritonitis.

BACKGROUND: Standard treatment for diffuse peritonitis due to colorectal perforation may be insufficient to suppress inflammatory reaction in sepsis. Thus, developing new treatments is important. This study aimed to examine whether intraperitoneal irradiation by artificial sunlight suppresses inflammatory reaction in a lipopolysaccharide (LPS)-induced peritonitis model after surgical treatments. MATERIALS AND METHODS: Mice were divided into naive, nontreatment (NT), and phototherapy (PT) groups. In the latter two groups, LPS was intraperitoneally administered to induce peritonitis and removed by intraperitoneal lavage after laparotomy. The PT group was irradiated with artificial sunlight intraperitoneally. We evaluated the local and systemic inflammatory reactions. Murine macrophages were irradiated with artificial sunlight after stimulation by LPS, and cell viability and expression of tumor necrotizing factor-α (TNF-α) were evaluated. RESULTS: As a local inflammatory reaction, the whole cell count, the expression of interleukin-6 and TNF-α in the intra-abdominal fluid, and the peritoneal thickness were significantly lower in the PT group than in the NT group. As a systematic inflammatory reaction, the expression of serum TNF-α, granulocyte macrophage colony-stimulating factor, monocyte chemotactic protein-1, macrophage inflammatory protein (MIP)-1α, and MIP-1ß were significantly lower in the PT group than in the NT group. Irradiation by artificial sunlight suppressed the expression of TNF-α in murine macrophages without affecting cell viability. CONCLUSIONS: Intraperitoneal irradiation by artificial sunlight could suppress local and systemic inflammatory reactions in the LPS-induced peritonitis murine model. These effects may be associated with macrophage immune responses.

Ginsenoside metabolite 20(S)-protopanaxatriol from Panax ginseng attenuates inflammation-mediated NLRP3 inflammasome activation.

ETHNOPHARMACOLOGICAL RELEVANCE: Panax ginseng C.A. Meyer (Araliaceae), has been used in traditional medicine for preventive and therapeutic purposes in Asian countries. One of the active ginsenoside metabolites, 20(S)-Protopanaxatriol (PPT), has been associated with diverse pharmacological effects, including anti-inflammatory properties. AIM OF THE STUDY: Although the capacity of PPT as an anti-inflammatory agent has been studied, this study aimed to explore the intrinsic mechanism of PPT in regulating inflammasome activation-mediated inflammatory responses in experimental models. MATERIALS AND METHODS: Lipopolysaccharide (LPS)-primed peritoneal macrophages in vitro was used to study the role of PPT on inflammasome activation. LPS-induced septic shock and monosodium urate (MSU)-induced murine peritonitis models were employed for in vivo evaluations. RESULTS: PPT attenuated NLRP3 inflammasome activation and also reduced ASC oligomerization, leading to attenuation of interleukin (IL)-1ß secretion. Further, PPT inhibited IL-1ß secretion in both LPS-induced septic shock and MSU-induced mouse peritonitis models. CONCLUSIONS: This study revealed that ginsenoside metabolite PPT, inhibits inflammation-mediated inflammasome activation and supported the traditional use of ginseng in treating various inflammatory disorders.

Anti-inflammatory activity of ß-caryophyllene combined with docosahexaenoic acid in a model of sepsis induced by Staphylococcus aureus in mice.

BACKGROUND: Sepsis is a set of serious organic manifestations caused by an infection, whose progression culminates in exacerbated inflammation and oxidative stress, poor prognosis, and high hospital costs. Antioxidants used against sepsis have been evaluated, including essential oils such as ß-caryophyllene (BCP), and polyunsaturated fatty acids, such as docosahexaenoic acid (DHA). The aim of this study was to evaluate the anti-inflammatory activity of the association of these two compounds. RESULTS: Treatment with BCP-DHA, at a dose of 200 µL/animal, significantly inhibited the migration of neutrophils in a Cg-induced peritonitis model. After Staphylococcus aureus infection, in the groups treated with BCP-DHA there was a significant decrease in the total and differential count of leukocytes, increased expression of cytokines TNF-α and IFN-γ in treated groups, an increase of IL-4 and IL-5 in B/D and B/D + SA groups, and an augmentation of IL-6 and IL-12 groups in B/D + SA groups. Histological and bacterial analysis revealed lower neutrophil migration and lower bacterial load in the infected and treated groups. CONCLUSION: In general, the BCP-DHA association presented anti-inflammatory activity against two different models of acute inflammation and infection, showing promising potential as a therapeutic adjuvant in sepsis. © 2019 Society of Chemical Industry.

Tanshinone IIA attenuates sepsis-induced immunosuppression and improves survival rate in a mice peritonitis model.

BACKGROUND: The importance of sepsis-induced immunosuppression and its contribution to mortality has recently emerged. In this study we examined the effects of Tanshinone II-A (TSN), a widely used traditional Chinese medicine, on immunosuppression in experimental peritonitis induced septic mice. MATERIALS AND METHODS: Sepsis was achieved by means of cecal ligation and puncture (CLP). TSN at different doses (5, 15 and 45 mg/kg, i.p.) were used at different time-points (0, 3, 6 and 12 h) after CLP to evaluate its effect on the survival of septic mice. In parallel experiments, mice given TSN at optimal dose and time-point were euthanized to collect peritoneal macrophages, blood and tissue samples at 24 h after the CLP. RESULTS: TSN improved the survival of septic mice in a dose- and time-dependent manner. TSN reduced CLP-induced serum biochemical parameters and protected organs from histopathological injuries. CLP-induced apoptosis and decreased percentages of splenic CD4+ and CD8+ T cells were reversed in TSN-treated mice. Moreover, CLP-induced formation of regulatory T cells (Treg) in the spleen was abolished in TSN-treated mice. CLP greatly decreased the levels of interferon-γ and interleukin (IL)-2 in the spleen, while the levels of IL-4 and IL-10 increased after CLP. TSN completely reversed these alterations and elicited a more-balanced Th1/Th2 response. Moreover, TSN promoted macrophage phagocytotic activity and improved bacterial clearance of septic mice. Lastly, TSN abolished CLP-triggered increase in serum HMBG1 level. And HMGB1 neutralization could increase the percentages of splenic CD3+CD4+/CD3+CD8+ lymphocytes and decreased the Treg population. CONCLUSIONS: Overall, our data suggest that TSN exerts immune modulatory effect and might be a useful strategy to ameliorate immunosuppression in polymicrobial sepsis.

Sphenodesme involucrata var. paniculata (C.B. Clarke) Munir.: Chemical characterization, anti-nociceptive and anti-inflammatory activities of methanol extract of leaves.

ETHNOPHARMACOLOGICAL RELEVANCE: Sphenodesme involucrata var. paniculata (C. B. Clarke) Munir is native as well as endemic to South India. Its leaves are used in folklore medicine to treat pain and rheumatism. OBJECTIVE: This study was aimed to investigate the chemical characterization, anti-nociceptive and mode of action underlying the anti-inflammatory effects of methanol extract of S. involucrata leaves (MESi). METHODS: Phytoconstituents of MESi was analyzed using colorimetric and liquid chromatography-mass spectrometry (LC-MS) methods, and the oral acute toxicity was evaluated in mice up to 2000 mg/kg. The anti-nociceptive effect was evaluated in hot plate and writhing tests; whereas the anti-inflammatory effect was investigated using carrageenan, cotton pellet and lipopolysaccharide (LPS)-induced peritonitis models at doses of 100, 200 and 400 mg/kg. Additionally nitric oxide (NO) and inflammatory cytokines levels were also evaluated. RESULTS: MESi exhibited the high content of phenolics and flavonoids as well as compounds like austricine, benzylglucosinolate, gossypin, justicidin B and cirsimarin were detected in LC-MS. In the acute toxicity study, oral administration of MESi did not cause any toxic effect and mortality up to 2000 mg/kg body weight in mice. In the anti-nociceptive tests, MESi augmented the latency period at higher dose (400 mg/kg), on the other hand attenuated writhings at the dose of 400 mg/kg by 87.87% (p < 0.001). In the carrageenan induced paw oedema MESi significantly inhibited the oedema formation at dose 400 mg/kg by 32.1%; besides, anti-inflammatory effect was registered in the cotton pellets-induced inflammation model at doses 200 and 400 mg/kg by 27.09% (p < 0.001) and 35.47% (p < 0.001) respectively. On the other hand, MESi appreciably reduced leukocyte, neutrophils infiltration, nitric oxide, TNF-α and IL-1ß levels and increased the IL-10 level in the (LPS)-induced peritonitis model. CONCLUSION: The results conclude that MESi has no acute toxic effect and it demonstrated potent anti-nociceptive and anti-inflammatory activities. Its anti-nociceptive activities are probably mediated through peripheral and central mechanisms. The anti-inflammatory effect of MESi involved the inhibition of neutrophils migration and the modulation of Th1 and Th2 cytokines, besides the attenuation of production of PGE2 and NO. LC-MS analysis revealed the predominant presence of the austricine, benzylglucosinolate, gossypin, justicidin B and cirsimarin compounds, which are possibly involved in the anti-nociceptive and anti-inflammatory effects of MESi. The current study provided supportive evidence for the folklore use of S. involucrata in the treatment of pain and inflammatory conditions.

Oridonin is a covalent NLRP3 inhibitor with strong anti-inflammasome activity.

Oridonin (Ori) is the major active ingredient of the traditional Chinese medicinal herb Rabdosia rubescens and has anti-inflammatory activity, but the target of Ori remains unknown. NLRP3 is a central component of NLRP3 inflammasome and has been involved in a wide variety of chronic inflammation-driven human diseases. Here, we show that Ori is a specific and covalent inhibitor for NLRP3 inflammasome. Ori forms a covalent bond with the cysteine 279 of NLRP3 in NACHT domain to block the interaction between NLRP3 and NEK7, thereby inhibiting NLRP3 inflammasome assembly and activation. Importantly, Ori has both preventive or therapeutic effects on mouse models of peritonitis, gouty arthritis and type 2 diabetes, via inhibition of NLRP3 activation. Our results thus identify NLRP3 as the direct target of Ori for mediating Ori's anti-inflammatory activity. Ori could serve as a lead for developing new therapeutics against NLRP3-driven diseases.

Anti-Inflammatory Activity of Epimedium brevicornu Maxim Ethanol Extract.

Epimedium brevicornu Maxim has been used as a traditional herbal drug in China. In this study, the anti-inflammatory effects of E. brevicornu Maxim ethanol extract (EBME) were investigated in RAW264.7 macrophages and mice challenged with lipopolysaccharide (LPS). Results showed that EBME attenuated inflammation by decreasing the production of several proinflammatory mediators, such as nitric oxide (NO), prostaglandin (PG) E2, inducible nitric oxide synthase, and cyclooxygenase-2, in LPS-stimulated RAW264.7 macrophages. EBME increased the expression of heme oxygenase-1 (HO-1) and promoted the nuclear translocation of nuclear factor erythroid 2-related factor 2. The inhibitory effects of EBME on LPS-stimulated NO and PGE2 expression were partially reversed by HO-1 inhibitor. EBME also elicited an anti-inflammatory effect by inhibiting the production of tumor necrosis factor-α, interleukin (IL)-1ß, and IL-6 in LPS-induced peritonitis. Therefore, EBME exhibited anti-inflammatory effects in vitro and in vivo.

Crude extract and fractions from Eugenia uniflora Linn leaves showed anti-inflammatory, antioxidant, and antibacterial activities.

BACKGROUND: This study showed phytochemical composition and evaluates the anti-inflammatory, and analgesic activities of crude extract (CE) and fractions from E. uniflora Linn leaves. METHODS: Polyphenols present in crude extract (CE), in aqueous fraction (AqF), and ethyl acetate (EAF) treated fractions from E. uniflora Linn leaves were shown by chromatographic analysis in order to conduct a phytochemical characterization. Antibacterial activity was evaluated based on minimum inhibitory concentrations (MICs) determined using the agar dilution method. Doses of 50, 100, and 200 mg/kg of the CE and fractions were applied for conducting in vivo models (male Swiss mice, 8-10 weeks old). The peritonitis experimental model was induced by carrageenan following of Myeloperoxidase activity (MPO), Total glutathione and malondialdehyde (MDA), IL-1ß and TNF-α levels by spectroscopic UV/VIS analysis. Antinociceptive activity was evaluated based on an abdominal writhing model and hot plate test. The results were statistically evaluated using one-way analysis of variance (ANOVA), followed by Bonferroni's post-hoc test. The level of statistical significance was p < 0.05. RESULTS: High-performance liquid chromatography with photodiode array detection (HPLC-DAD) detected varying concentrations of gallic acid, ellagic acid, and myricitrin in the CE and fractions obtained from E. uniflora Linn leaves (0.05-0.87%w/w, 0.20-0.32%w/w, and 1.71-6.56%w/w, respectively). In general, the CE had lower MIC values than the fractions, including the lowest MIC against the MRSA strain. The CE and AqF also significantly reduced leukocyte migration and MPO activity (p < 0.05). In addition, AqF significantly reduced IL-1ß and TNF-α levels (p < 0.05). Furthermore, the CE and fractions exhibited an antioxidant effect (p < 0.05) and peripheral analgesic activity (p < 0.05). CONCLUSIONS: The CE and fractions from the studied E. uniflora Linn leaves exhibited antibacterial, anti-inflammatory, antioxidant, and analgesic activity in the performed assays.

Activated Protein C Attenuates Severe Inflammation by Targeting VLA-3high Neutrophil Subpopulation in Mice.

The host injury involved in multiorgan system failure during severe inflammation is mediated, in part, by massive infiltration and sequestration of hyperactive neutrophils in the visceral organ. A recombinant form of human activated protein C (rhAPC) has shown cytoprotective and anti-inflammatory functions in some clinical and animal studies, but the direct mechanism is not fully understood. Recently, we reported that, during endotoxemia and severe polymicrobial peritonitis, integrin VLA-3 (CD49c/CD29) is specifically upregulated on hyperinflammatory neutrophils and that targeting the VLA-3high neutrophil subpopulation improved survival in mice. In this article, we report that rhAPC binds to human neutrophils via integrin VLA-3 (CD49c/CD29) with a higher affinity compared with other Arg-Gly-Asp binding integrins. Similarly, there is preferential binding of activated protein C (PC) to Gr1highCD11bhighVLA-3high cells isolated from the bone marrow of septic mice. Furthermore, specific binding of rhAPC to human neutrophils via VLA-3 was inhibited by an antagonistic peptide (LXY2). In addition, genetically modified mutant activated PC, with a high affinity for VLA-3, shows significantly improved binding to neutrophils compared with wild-type activated PC and significantly reduced neutrophil infiltration into the lungs of septic mice. These data indicate that variants of activated PC have a stronger affinity for integrin VLA-3, which reveals novel therapeutic possibilities.

Lycopene rich extract from red guava (Psidium guajava L.) displays anti-inflammatory and antioxidant profile by reducing suggestive hallmarks of acute inflammatory response in mice.

This study investigated the anti-inflammatory activity of the extract (LEG) and purified (LPG) lycopene from guava (Psidium guajava L.), as well as some mechanisms possibly involved in this effect. The anti-inflammatory activity was initially assessed using paw edema induced by Carrageenan, Dextran, Compound 48/80, Histamine and Prostaglandin E2 in Swiss mice. A peritonitis model was used to evaluate neutrophil migration, the activity of myeloperoxidase (MPO) and reduced glutathione (GSH) concentration; while the effect on the expression of iNOS, COX-2 and NF-κB, was assessed by immunohistochemistry analysis. Results showed that oral and intraperitoneal administration of LEG and LPG inhibited inflammation caused by carrageenan. LPG (12.5mg/kg p.o.) significantly inhibited the edema formation induced by different phlogistic agents and immunostaining for iNOS, COX-2 and NF-κB. Leukocytes migration in paw tissue and peritoneal cavity was reduced, as well as MPO concentration, whereas GSH levels increased. Thus, lycopene-rich extract from red guava has beneficial effect on acute inflammation, offering protection against the consequences of oxidative stress by downregulating inflammatory mediators and inhibiting gene expression involved in inflammation.

PG2, a botanically derived drug extracted from Astragalus membranaceus, promotes proliferation and immunosuppression of umbilical cord-derived mesenchymal stem cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Astragalus membranaceus is used to manage the deficiency of vital energy in traditional Chinese medicine and confirmed to have many biological functions. Mesenchymal stem cells (MSCs) possess immunosuppressive effects, and are widely used for regenerative medicine and immune disorders. AIMS OF STUDY: This study investigated the effects of Astragalus polysaccharides (APS) on umbilical cord-derived MSCs (UCMSCs), including morphology, surface marker expression, proliferation, differentiation, and in-vitro and in-vivo immunosuppressive capacities. MATERIALS AND METHODS: MSCs isolated from umbilical cords were used. PG2 injection, a botanically derived drug containing a mixture of APS, was added into the culture medium to prepare PG2-treated UCMSCs. The morphology, surface marker expression, proliferation, and differentiation of UCMSCs were determined. The in-vitro immunosuppressive effects of UCMSCs were examined by peripheral blood mononuclear cell (PBMC) proliferation assay. The in-vivo effects were evaluated by circulatory inflammation-associated cytokine levels in mice with septic peritonitis induced by cecal ligation and puncture (CLP) operation. RESULTS: Compared with control UCMSCs, UCMSCs had higher population doublings when exposed to PG2-containing medium (P = 0.003). The reduction rates of PBMC proliferation after phytohemagglutinin stimulation increased significantly when UCMSCs were treated with PG2 (P = 0.004). The serum levels of inflammation-associated cytokines, including TNF-α, IL-6, MCP-1, IFN-γ, and IL-1ß, were significantly lower at 6h after CLP in the mice receiving PG2-treated UCMSCs. CONCLUSIONS: Our results demonstrated that PG2 can enhance UCMSC proliferation and their in-vitro and in-vivo immunosuppressive effects. Consequently, UCMSCs can be obtained in earlier passages to avoid senescence, and sufficient cells can be acquired faster for clinical use. With stronger immunosuppressive effects, UCMSCs may treat immune disorders more effectively. Further studies are warranted.

Oral omega-3 fatty acids promote resolution in chemical peritonitis.

BACKGROUND: Recent studies suggest that purified omega-3 fatty acids may attenuate acute inflammation and hasten the transition to healing. In this study, we tested the hypothesis that pretreatment with omega-3-rich fish oil (FO) would promote resolution of peritoneal inflammation through production of specific lipid mediators. METHODS: C57/BL6 mice were given a daily 200-µL oral gavage of saline (CTL) or FO (1.0-1.5 g/kg/d docosahexaenoic acid and 1.3-2.0 g/kg/d eicosapentaenoic acid) for 7 d before chemical peritonitis was induced with thioglycollate. Peritoneal lavage fluid was collected before induction and at days 2 and 4 after peritonitis onset. Prostaglandin E2 (PGE2), Leukotriene B4 (LTB4), Resolvin D1 (RvD1), and the composition of immune cell populations were examined in peritoneal lavage exudates. Cells harvested from the peritoneum were assessed for macrophage differentiation markers, phagocytosis, and lipopolysaccharide-induced cytokine secretion profiles (interleukin [IL]-6, IL-10, IL-1ß, TNFα). RESULTS: The ratio of RvD1 to pro-inflammatory PGE2 and LTB4 was increased in the peritoneal cavity of FO-supplemented animals. FO induced a decrease in the number of monocytes in the lavage fluid, with no change in the number of macrophages, neutrophils, or lymphocytes. Macrophage phagocytosis and M1/M2 messenger RNA markers were unchanged by FO with the exception of decreased PPARγ expression. FO increased ex vivo TNFα secretion after stimulation with lipopolysaccharide. CONCLUSIONS: Our findings provide evidence that nutraceutically relevant doses of FO supplements given before and during chemical peritonitis shift the balance of lipid mediators towards a proresolution, anti-inflammatory state without drastically altering the number or phenotype of local innate immune cell populations.

Unconventional Human T Cells Accumulate at the Site of Infection in Response to Microbial Ligands and Induce Local Tissue Remodeling.

The antimicrobial responsiveness and function of unconventional human T cells are poorly understood, with only limited access to relevant specimens from sites of infection. Peritonitis is a common and serious complication in individuals with end-stage kidney disease receiving peritoneal dialysis. By analyzing local and systemic immune responses in peritoneal dialysis patients presenting with acute bacterial peritonitis and monitoring individuals before and during defined infectious episodes, our data show that Vγ9/Vδ2(+) γδ T cells and mucosal-associated invariant T cells accumulate at the site of infection with organisms producing (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate and vitamin B2, respectively. Such unconventional human T cells are major producers of IFN-γ and TNF-α in response to these ligands that are shared by many microbial pathogens and affect the cells lining the peritoneal cavity by triggering local inflammation and inducing tissue remodeling with consequences for peritoneal membrane integrity. Our data uncover a crucial role for Vγ9/Vδ2 T cells and mucosal-associated invariant T cells in bacterial infection and suggest that they represent a useful predictive marker for important clinical outcomes, which may inform future stratification and patient management. These findings are likely to be applicable to other acute infections where local activation of unconventional T cells contributes to the antimicrobial inflammatory response.

Cerbera manghas methanol extract exerts anti-inflammatory activity by targeting c-Jun N-terminal kinase in the AP-1 pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Cerbera manghas L. (Apocynaceae) is a medicinal plant traditionally used to ameliorate the clinical signs of inflammatory diseases and hypertension. AIM OF STUDY: Although C. manghas L. has long been used as a traditional remedy for various diseases, the underlying molecular and cellular mechanisms are poorly understood. A detailed investigation of these mechanisms is necessary to demonstrate the ethnopharmaceutical utility of this plant. MATERIALS AND METHODS: The effects of C. manghas methanol extract (Cm-ME) on the production of inflammatory mediators and the expression of proinflammatory cytokines and identification of molecular targets were investigated using lipopolysaccharide (LPS)-treated macrophages in vitro. In addition, the inhibitory effects of Cm-ME orally administered were tested by LPS/D-galactosamine (D-GalN)-induced hepatitis and LPS-induced peritonitis mouse models in vivo. RESULTS: Cm-ME downregulated the production of prostaglandin (PG)E2 and the mRNA expression of cyclooxygenase (COX)-2, tumor necrosis factor (TNF)-α, and interleukin (IL)-1ß in LPS-stimulated RAW264.7 cells under non-toxic concentration of Cm-ME. This extract inhibited the nuclear translocation of c-Jun and p-ATF2, the phosphorylation of JNK and p38, and AP-1 activity. Western blot analysis and in vitro kinase assay confirmed that JNK is a direct pharmacological target of Cm-ME action. In addition, Cm-ME significantly ameliorated the clinical signs of LPS/D-GalN-induced hepatitis and lowered the production of nitric oxide (NO) and the phosphorylation of JNK in LPS-induced peritonitis conditions. CONCLUSION: Cm-ME exerts anti-inflammatory actions on LPS-stimulated macrophages and in mouse models of acute inflammatory disease. These actions are predominantly mediated by targeting JNK in the AP-1 signaling pathway.

Evidence of anti-inflammatory and antinociceptive activities of Plinia edulis leaf infusion.

ETHNOPHARMACOLOGICAL RELEVANCE: Plinia edulis (Vell.) Sobral (Myrtaceae) is native and endemic to the Brazilian Atlantic Rainforest. Popularly known as "cambucá", it has been used in folk medicine for the treatment of stomach disorders, diabetes, bronchitis, inflammation and as tonic. Although there are numerous records concerning its popular use as analgesic and anti-inflammatory, scientific information regarding these pharmacological activities is limited. Therefore, the aim of this study was to characterize the anti-inflammatory and antinociceptive activity of P. edulis leaf infusion (AEPe) in mice. MATERIALS AND METHODS: The acetic acid-induced writhing response and mechanical nociceptive paw tests were used to evaluate the antinociceptive activity. Carrageenan-induced paw edema and lipopolysaccharide-induced peritonitis were used to investigate the anti-inflammatory activity. The substances in AEPe were identified by HPLC-MS analysis. RESULTS: At the test doses 30-300mg/kg p.o., AEPe has clearly exhibited anti-inflammatory effects, reducing carrageenan-induced paw edema and inhibiting leukocyte recruitment into the peritoneal cavity. The infusion has shown significant antinociceptive activity in both models of nociception. Gallic acid, myricitrin, guaijaverin, quercitrin, quercetin, corosolic acid, maslinic acid, oleanolic acid and ursolic acid were identified in AEPe. CONCLUSION: P. edulis infusion presented antinociceptive and anti-inflammatory activities in all experiments realized in this study, which could be related to the presence of triterpenoids and flavonoids. These results provide scientific support for the traditional use of this species in the management of pain and inflammation.

Juniperus rigida Sieb. extract inhibits inflammatory responses via attenuation of TRIF-dependent signaling and inflammasome activation.

ETHNOPHARMACOLOGICAL RELEVANCE: Juniperus rigida Sieb. (J. rigida) is used for medicinal purposes in Asian countries to treat inflammation-related disorders, such as neuralgia, dropsy, and gout. AIM OF THE STUDY: The anti-inflammatory effects of J. rigida extract (JR) and its underlying mechanisms were explored both in in vitro cell lines and in vivo metabolic disease models. MATERIAL AND METHODS: Lipopolysaccharide (LPS)-stimulated RAW264.7 murine macrophages were used to study the changes in inflammatory responses in vitro. Bone marrow-derived macrophages (BMDMs) were used to study the regulatory effect of JR on inflammasome activation. The murine model for monosodium urate (MSU)-induced peritonitis and high-fat diet (HFD)-induced type 2 diabetes were employed to study the effect of JR on in vivo efficacy. RESULTS: JR suppressed the MSU-induced in vivo inflammatory response by attenuation of proinflammatory cytokines, including interleukin (IL)-1ß, IL-6, and tumor necrosis factor-alpha (TNF-α). In the in vitro study, JR suppressed IL-1ß secretion via regulation of apoptosis-associated speck-like protein containing a CARD (ASC) oligomerization, leading to the inhibition of inflammasome activation. JR also inhibited the LPS-stimulated release of proinflammatory mediators, such as nitric oxide (NO), TNF-α, and IL-6 in RAW264.7 cells. The inhibitory effects of JR were mediated through the regulation of the TRIF-dependent signaling pathway from JAK1/STAT1 phosphorylation. Furthermore, JR showed inhibitory effects on HFD-induced type 2 diabetes in a mouse model through the regulation of blood glucose and serum IL-1ß. CONCLUSIONS: Our results indicate that JR attenuates both LPS-stimulated and danger-signal-induced inflammatory responses in macrophages via regulation of the key inflammatory mechanisms, providing scientific support for its traditional use in the treatment of various inflammation-related metabolic disorders.