Production of Cytokine and NO by RAW 264.7 Macrophages and PBMC In Vitro Incubation with Flavonoids

Inhibitory Effects of Naringenin on LPS-Induced Skin Inflammation by NF-κB Regulation in Human Dermal Fibroblasts

Flavonoids are important natural compounds characterized by their extensive biological activities. Citrus flavonoids represent a significant segment of the broader flavonoid category. Naringenin, an integral part of this series, is recognized for its powerful anti-inflammatory and antioxidant properties. In addition, considering the lack of existing research on naringenin's potential effectiveness and intracellular mechanisms of action in skin-related applications, especially as a cosmetic ingredient, this study aimed to explore naringenin's role in reducing the fundamental generation of reactive oxygen species. This was achieved by examining its inhibitory effects on the expression levels of NADPH oxidase and iNOS, ultimately leading to a reduction in NO production. This research examined the anti-inflammatory and antioxidant capacities of naringenin by employing a cellular senescence model of LPS-induced HDFs. The evaluation of naringenin's efficacy was validated through several investigative procedures, including the NF-κB luciferase assay, ELISA assay, and qRT-PCR. To verify the anti-inflammatory effectiveness of naringenin, we measured the responsive elements of NF-κB using a luciferase reporter assay. This assessment revealed that naringenin could decrease the concentration of genes activated by NF-κB. Moreover, we found that naringenin inhibited the transcriptional expression of known NF-κB-regulated inflammatory cytokines, including IL-1β, IL-6, and IL-8. In addition, results from the qRT-PCR analysis indicated that naringenin facilitated a reduction in iNOS expression. Based on the data gathered and analyzed in this study, it can be conclusively inferred that naringenin possesses promising potential as a cosmetic ingredient, offering both anti-inflammatory and antioxidant benefits.

Efficient biotransformation of naringenin to naringenin α-glucoside, a novel α-glucosidase inhibitor, by amylosucrase from Deinococcus wulumuquiensis

Amylosucrase (ASase) efficiently biosynthesizes α-glucoside using flavonoids as acceptor molecules and sucrose as a donor molecule. Here, ASase from Deinococcus wulumuqiensis (DwAS) biosynthesized more naringenin α-glucoside (NαG) with sucrose and naringenin as donor and acceptor molecules, respectively, than other ASases from Deinococcus sp. The biotransformation rate of DwAS to NαG was 21.3% compared to 7.1-16.2% for other ASases. Docking simulations showed that the active site of DwAS was more accessible to naringenin than those of others. The 217th valine in DwAS corresponded to the 221st isoleucine in Deinococcus geothermalis AS (DgAS), and the isoleucine possibly prevented naringenin from accessing the active site. The DwAS-V217I mutant had a significantly lower biosynthetic rate of NαG than DwAS. The kcat/Km value of DwAS with naringenin as the donor was significantly higher than that of DgAS and DwAS-V217I. In addition, NαG inhibited human intestinal α-glucosidase more efficiently than naringenin.

Fine-tuning of mononuclear phagocytes for improved inflammatory responses: role of soybean-derived immunomodulatory compounds

The concept of inflammation encompasses beneficial and detrimental aspects, which are referred to as infectious and sterile inflammations, respectively. Infectious inflammation plays a crucial role in host defense, whereas sterile inflammation encompasses allergic, autoimmune, and lifestyle-related diseases, leading to detrimental effects. Dendritic cells and macrophages, both of which are representative mononuclear phagocytes (MNPs), are essential for initiating immune responses, suggesting that the regulation of MNPs limits excessive inflammation. In this context, dietary components with immunomodulatory properties have been identified. Among them, soybean-derived compounds, including isoflavones, saponins, flavonoids, and bioactive peptides, act directly on MNPs to fine-tune immune responses. Notably, some soybean-derived compounds have demonstrated the ability to alleviate the symptom of allergy and autoimmunity in mouse models. In this review, we introduce and summarize the roles of soybean-derived compounds on MNP-mediated inflammatory responses. Understanding the mechanism by which soybean-derived molecules regulate MNPs could provide valuable insights for designing safe immunomodulators.

Enzyme-treated red rice (Oryza sativa L.) bran extracts mitigate inflammatory markers in RAW 264.7 macrophage cells and exhibit anti-inflammatory efficacy greater/comparable to ferulic acid, catechin, γ-tocopherol, and γ-oryzanol

ETHNOPHARMACOLOGICAL RELEVANCE

Rice (Oryza sativa L.), a staple food for a significant portion of the global population, has been recognized for its traditional medicinal properties for centuries. Rice bran, a by-product of rice milling, contains many bioactive compounds with potential pharmaceutical and therapeutic benefits. In recent years, research has highlighted the anti-inflammatory potential of rice bran, contributed by the bioactive components concentrated in their bran but, unfortunately, entrapped in the bran matrix, with limited bioavailability. Previous studies have reported that the enzymatic treatment of rice bran improves the bran's bioactive compound profile but did not investigate its impact on chronic conditions such as inflammation.

AIM OF THE STUDY

This study investigates the anti-inflammatory effects of endo-1,4-β-xylanase (ERB) and Viscozyme (VRB) treated red rice bran extracts against lipopolysaccharide-induced inflammation in RAW264.7 macrophages in comparison with non-enzyme-treated bran (CRB). Further established their efficacy with known anti-inflammatory compounds-ferulic acid (FA), catechin (CAT), γ-tocopherol (GTP), and γ-oryzanol (ORZ).

MATERIALS AND METHODS

The RAW 264.7 macrophage cells were pre-treated with non-toxic concentrations (10-200 μg/mL) of FA, CAT, GTP, ORZ, CRB, ERB, and VRB, followed by inflammatory stimulation with LPS for 24 h. Further, the cell supernatant and pellets were harvested to study the anti-inflammatory effects by evaluating and measuring their efficacy in inhibiting pro-inflammatory cytokines (TNF-α, IL-6, IL-10, IL-1β) and mediators (ROS, NO, PGE2, COX2, iNOS) through biochemical, ELISA, and mRNA expression studies.

RESULTS

The findings showed that both ERB and VRB effectively inhibited the production of pro-inflammatory markers (TNF-α, IL-6) and mediators (ROS, NO, PGE2) by downregulating mRNA expressions of inflammatory genes (TNF-α, IL-1β, IL-6, IL-10, COX2, iNOS) and demonstrated anti-inflammatory efficacy higher than CRB. On comparison, ERB demonstrated exceptional efficacy by causing a reduction of 48% in ROS, 20% in TNF-α, and 23% in PGE2 at 10 μg/mL, surpassing the anti-inflammatory capabilities of all the bioactive compounds, FA and ORZ, respectively. At the same time, VRB exhibited remarkable efficacy by reducing NO production by 52% at 200 μg/mL and IL-6 by 66% at 10 μg/mL, surpassing FA, CAT, ORZ, and GTP. Further, ERB downregulated the mRNA expression of IL-10 and iNOS, while VRB downregulated TNF-α, IL-1β, and COX2 expression. Both extracts equally downregulated IL-6 expression at 10 μg/mL, demonstrating the efficacy more remarkable/on par with established anti-inflammatory compounds.

CONCLUSIONS

Overall, enzyme-treated rice bran/extract, particularly ERB, possesses excellent anti-inflammatory properties, making them promising agents for alternatives to contemporary nutraceuticals/functional food against inflammatory diseases.

From nature to therapy: Luteolin's potential as an immune system modulator in inflammatory disorders

Inflammation is an essential immune response that helps fight infections and heal tissues. However, chronic inflammation has been linked to several diseases, including cancer, autoimmune disorders, cardiovascular diseases, and neurological disorders. This has increased interest in finding natural substances that can modulate the immune system inflammatory signaling pathways to prevent or treat these diseases. Luteolin is a flavonoid found in many fruits, vegetables, and herbs. It has been shown to have anti-inflammatory effects by altering signaling pathways in immune cells. This review article discusses the current research on luteolin's role as a natural immune system modulator of inflammatory signaling mechanisms, such as its effects on nuclear factor-kappa B, mitogen-activated protein kinases, Janus kinase/signal transducer and activator of transcription, and inflammasome signaling processes. The safety profile of luteolin and its potential therapeutic uses in conditions linked to inflammation are also discussed. Overall, the data point to Luteolin's intriguing potential as a natural regulator of immune system inflammatory signaling processes. More research is needed to fully understand its mechanisms of action and possible therapeutic applications.

Comparative study on the impacts of visnagin and its methoxy derivative khellin on human lymphocyte proliferation and Th1/Th2 balance

BACKGROUND

Visnagin is a phenolic and natural compound in turmeric and fenugreek, and its anti-inflammatory effect has been indicated. Therefore, this study aimed to investigate and compare the anti-inflammatory properties of visnagin and its methoxy derivative khellin on human lymphocytes.

METHODS

Human lymphocytes were treated with khellin, visnagin (10, 30, and 100 µM), and dexamethasone (0.1 mM) in the presence of phytohemagglutinin (PHA). The levels of cell proliferation, nitric oxide (NO), glutathione (GSH), malondialdehyde (MDA), and MDA/GSH ratio were measured using biochemistry methods. Furthermore, the mRNA levels of interferon-γ (IFN-γ), interleukin (IL)-4, and IL-10 were assessed using real-time PCR, while IFN-γ/IL-4(Th₁/Th₂), IFN-γ/IL-10(Th₁/T_reg), and IL-4/IL-10(Th₂/T_reg) ratios were made by dividing their exact values.

RESULTS

In the PHA-stimulated group, GSH and IFN-γ/IL-4 levels were markedly diminished, but other variables were significantly elevated compared to the control group. Khellin and visnagin significantly declined the levels of cell proliferation, MDA, MDA/GSH ratio, and NO production. Khellin and visnagin concentration-dependently diminished IFN-γ and IL-4 levels and increased IL-10 levels compared to the PHA-stimulated group. Two higher concentrations of khellin and visnagin (30 and 100 μM) considerably diminished the IFN-γ, IFN-γ/IL-10, and IL-4/IL-10 values compared to the PHA-stimulated group. However, 100 µM of khellin and visnagin significantly increased GSH level compared to the PHA-stimulated group.

CONCLUSIONS

In PHA-stimulated lymphocytes, representing Th₂ dominant allergic diseases, khellin and visnagin provides more specific anti-oxidant, anti-inflammatory, and immunomodulatory functions than dexamethasone. In addition, the effects of khellin were more prominent than visnagin.

Crocetin regulates Th1/Th2 and Th17/Treg balances, nitric oxide production, and nuclear localization of NF-κB in Th2-provoked and normal situations in human-isolated lymphocytes

Crocetin is a natural carotenoid dicarboxylic acid derived from Crocus sativus. It has been utilized as natural biomedicine with healing effects. The immunoregulatory and anti-inflammatory properties may cause the biological activities of crocetin. Nevertheless, it is not still clear how this compound acts and causes an immune-modulatory impact on human lymphocytes. The effects of three concentrations (5, 10, and 20 μM) of crocetin or dexamethasone (0.1 mM) were assessed on gene expression and secretion of cytokines, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) level, and nitric oxide (NO) production in phytohaemagglutinin (PHA)-stimulated and non-stimulated lymphocytes. By incubation with PHA, gene expression and cytokine concentration comprising interferon (IFN)-γ, interleukin (IL)-17A, IL-10, and IL-4 were increased, along with NF-κB concentration and NO production (all, p < 0.001). In comparison with the controls, an alteration occurred in the T-helper (Th)2/Th1 and Th17/Treg balance in the stimulated lymphocyte toward a Th2 and Th17 response. In stimulated cells, crocetin and dexamethasone decreased pro-inflammatory significantly and increased anti-inflammatory cytokines and related gene expression, respectively. Moreover, Th17/Treg and Th1/Th2 balance was changed toward Treg and Th1 significantly reducing NF-κB and NO levels (p < 0.05 to p < 0.001). Promoting effects were represented by crocetin on T-cell subsets to Treg and Th1. Hence, it can have therapeutic value for treating predominant diseases of Th2 or Th17 cells.

Understanding immune-modulatory efficacy in vitro

Boosting or suppressing our immune system represents an attractive adjunct in the treatment of infections including SARS-CoV-2, cancer, AIDS, malnutrition, age related problems and some inflammatory disorders. Thus, there has been a growing interest in exploring and developing novel drugs, natural or synthetic, that can manipulate our defence mechanism. Many of such studies, reported till date, have been designed to explore effect of the therapeutic on function of macrophages, being a key component in innate immune system. Indeed, RAW264.7, J774A.1, THP-1 and U937 cell lines act as ideal model systems for preliminary investigation and selection of dose for in vivo studies. Several bioassays have been standardized so far where many techniques require high throughput instruments, cost effective reagents and technical assistance that may hinder many scholars to perform a method demanding compilation of available protocols. In this review, we have taken an attempt for the first time to congregate commonly used in vitro immune-modulating techniques explaining their principles. The study detected that among about 40 different assays and more than 150 sets of primers, the methods of cell proliferation by MTT, phagocytosis by neutral red, NO detection by Griess reaction and estimation of expression of TLRs, COX-2, iNOS, TNF-α, IL-6 and IL-1β by PCR have been the most widely used to screen the therapeutics under investigation.

Characteristics of an In Vitro Mesenteric Lymph Node Cell Suspension Model and Its Possible Association with In Vivo Functional Evaluation

In a previous study, we uncovered three immune-responsive patterns of gut microbes using an in vitro mesenteric lymph node cell suspension model, abbreviated as the MLN model hereafter. We used Akkermansia muciniphila and Clostridium butyricum as the first group directly inducing an immune response, Bifidobacterium sp. and Bacteroides sp. as the second group evoking an immune response with the help of stimuli (anti-CD3 and anti-CD28 antibodies), and Lactobacillus sp. as the third group blunting the immune response with or without stimuli. Our group previously clarified the immune-activation characteristics of A. muciniphila and linked its in vivo immune induction effect in GF and SPF mice under homeostasis. In the present study, we supplemented the characteristics of C. butyricum and B. bifidum in the in vitro MLN model and addressed the specific elements of the model. Finally, we used an in vivo TNBS-challenge model to show the functional differences between these species with different response patterns in vitro. The results showed that C. butyricum and B. bifidum evoked an immune response in vitro in a dose-dependent and strain-unique manner. Although TLR2, rather than TLR4, is indispensable for immune activation in the present in vitro model, it may not involve interaction between TLR2 and bacterial ligands. Like the PBMC model, the present in vitro MLN model is highly dependent on cell resources and should be given more attention when used to conduct a quantitative comparison. Finally, a mixture of two strong immunogenic strains, A. muciniphila and C. butyricum, significantly increased the mortality of TNBS-challenged (2,4,6-trinitrobenzene sulfonic acid, TNBS) mice, indicating a possible link between the in vitro MLN model and in vivo functional evaluation. However, more evidence is needed to clarify the associations and underlying mechanisms.

Overview of the Antioxidant and Anti-Inflammatory Activities of Selected Plant Compounds and Their Metal Ions Complexes

Numerous plant compounds and their metal-ion complexes exert antioxidative, anti-inflammatory, anticancer, and other beneficial effects. This review highlights the different bioactivities of flavonoids, chromones, and coumarins and their metal-ions complexes due to different structural characteristics. In addition to insight into the most studied antioxidative properties of these compounds, the first part of the review provides a comprehensive overview of exogenous and endogenous sources of reactive oxygen and nitrogen species, oxidative stress-mediated damages of lipids and proteins, and on protective roles of antioxidant defense systems, including plant-derived antioxidants. Additionally, the review covers the anti-inflammatory and antimicrobial activities of flavonoids, chromones, coumarins and their metal-ion complexes which support its application in medicine, pharmacy, and cosmetology.

Fisetin Attenuates Lipopolysaccharide-Induced Inflammatory Responses in Macrophage

Several studies have reported the efficacy and safety of polyphenols in human health; however, the verification of their efficacy remains insufficient. The aim of this study was to examine whether fisetin, one of flavonoids prevalently present in fruits and vegetables, could suppress lipopolysaccharide- (LPS-) induced inflammatory responses in macrophages. LPS increased proinflammatory mRNA abundance (MCP 1, IL-1β, and iNOS) but were suppressed by fisetin. The increment of nitric oxide by LPS, an oxidative stress factor, was attenuated by fisetin. In addition, LPS-enhanced phosphorylation of mitogen-activated protein kinase (ERK and JNK) was reduced. Finally, fisetin attenuated the expression or activity of uPA, uPAR, MMP-2, and MMP-9, which are known as associated factors of macrophage recruitment or infiltration. In conclusion, fisetin is a promising therapeutic agent for macrophage-related inflammation diseases, like sepsis and atherosclerosis.

Fisetin inhibits inflammation and induces autophagy by mediating PI3K/AKT/mTOR signaling in LPS-induced RAW264.7 cells

Background

Fisetin, a natural potent flavonoid, has various beneficial, pharmacological activities. In this study, we investigated expression changes of the fisetin regulating genes in lipopolysaccharide (LPS)-treated RAW264.7 cells and explored the role of fisetin in inflammation and autophagy.

Methods and results

Microarray analysis identified 1,071 genes that were regulated by fisetin in LPS-treated RAW264.7 cells, and these genes were mainly related to the process of immune system response. Quantitative real-time polymerase chain reaction and Bio-Plex analysis indicated that fisetin decreased the expression and secretion of several inflammatory cytokines in cells administered with LPS. Western blot analysis and immunofluorescence assay showed that fisetin decreased microtubule-associated protein 1 light-chain 3B (LC3B) and lysosome-associated membrane protein 1 (LAMP1) expression in LPS-treated cells, while the autophagy inhibitor chloroquine (CQ) could partially reverse this effect. In addition, fisetin reduced the elevated expression of p-PI3K, p-AKT and p-mTOR induced by LPS in a concentration-dependent manner.

Conclusions

Fisetin diminished the expression and secretion of inflammatory cytokines and facilitated autophagosome-lysosome fusion and degradation in LPS-treated RAW264.7 cells via inhibition of the PI3K/AKT/mTOR signaling pathway. Overall, the results of this study provide new clues for the anti-inflammatory mechanism of fisetin and explain the crosstalk between autophagy and inflammation to some extent.

Efficacy of amiodarone and voriconazole combination therapy in cutaneous leishmaniasis in the mice experimentally infected with Leishmania major

INTRODUCTION

The aim of the present study was to evaluate in vitro and in vivo efficacy of combination therapy of amiodarone and voriconazole against Leishmania major and investigating immune and wound healing responses of cutaneous leishmaniasis to this combination therapy.

METHODS

For in vitro study, replication of L. major promastigotes and intracellular amastigotes were investigated in the presence and absence of amiodarone and voriconazole. Isobologram construction and calculation of the Fractional Inhibitory Concentration (FIC) were performed. After the appearance of ulcers on the base of tails of BALB/c mice, treatment was initiated by a combination of amiodarone at 40 mg/kg plus voriconazole at 30 mg/kg orally and glucantime at 60 mg/kg intraperitoneally for 28 consecutive days.

RESULTS

According to the concave isobologram and fractional inhibitory concentration <1, combination of amiodarone plus voriconazole had synergistic effects against L. major promastigotes and intracellular amastigotes. There were less inflammatory cells, more fibroblasts and more collagen deposition in tissue sections in the mice treated with combined drugs compared to the vehicle and untreated mice. Increased glutathione peroxidase activity and decreased malondialdehyde, Interleukin-6, and Tumor necrosis factor-α levels were detected in the combination therapy group in comparison to the vehicle and untreated groups.

CONCLUSIONS

It seems a combination of amiodarone plus voriconazole can be a rational and promising therapeutic approach in the treatment of cutaneous leishmaniasis.

Can Natural Polyphenols Help in Reducing Cytokine Storm in COVID-19 Patients?

SARS-CoV-2 first emerged in China during late 2019 and rapidly spread all over the world. Alterations in the inflammatory cytokines pathway represent a strong signature during SARS-COV-2 infection and correlate with poor prognosis and severity of the illness. The hyper-activation of the immune system results in an acute severe systemic inflammatory response named cytokine release syndrome (CRS). No effective prophylactic or post-exposure treatments are available, although some anti-inflammatory compounds are currently in clinical trials. Studies of plant extracts and natural compounds show that polyphenols can play a beneficial role in the prevention and the progress of chronic diseases related to inflammation. The aim of this manuscript is to review the published background on the possible effectiveness of polyphenols to fight SARS-COV-2 infection, contributing to the reduction of inflammation. Here, some of the anti-inflammatory therapies are discussed and although great progress has been made though this year, there is no proven cytokine blocking agents for COVID currently used in clinical practice. In this regard, bioactive phytochemicals such as polyphenols may become promising tools to be used as adjuvants in the treatment of SARS-CoV-2 infection. Such nutrients, with anti-inflammatory and antioxidant properties, associated to classical anti-inflammatory drugs, could help in reducing the inflammation in patients with COVID-19.

Investigating chemical changes during Snake fruit and Black tea Kombucha fermentation and the associated immunomodulatory activity in Salmonella typhi-infected mice

This study uncovered the chemical changes during kombucha's fermentation process and revealed the associated immunomodulatory activity in Salmonella typhi-infected mice. The snake fruit juice and black tea extract were processed into kombucha (a beverage known for its health benefits) by fermentation with SCOBY culture at room temperature for  14 days. Snake fruit kombucha showed high changes in fermentation parameters (total acidity, pH, and total sugar), as well as bioactive compounds and antioxidant activity. Salmonella typhi demonstrated a reduction in the population of CD8+TNFα+ and CD4+IFNγ+ of infected experimental animals. Both snake fruit kombucha and black tea kombucha have the potential to be utilized as an immunomodulator to circumvent unstable conditions of the immune system caused by Salmonella typhi. Black tea kombucha and snake fruit kombucha cancan raise the production of CD8+TNFα+ and CD4+IFNγ+ in mice infected with Salmonella typhi. In the group of normal mice, black tea and snake fruit kombucha were able to lower down the production of CD8+TNFα+, which is a potent mechanism to modulate the immune system. Further research is required to highlight the mechanism and role of black tea kombucha and snake fruit kombucha in the immune response that modulates and treats infection by Salmonella typhi.

Effect of Formulated Artocarpus champeden Extract on Parasite Growth and Immune Response of Plasmodium berghei-Infected Mice

Background

The ethanol extract of Artocarpus champeden stem bark (ACEE) has been proven to exhibit antimalarial activity. Despite the antimalarial effects observed, mechanisms of immune response to explain the antimalarial activity of ACEE remain poorly characterized. Here, we show the production of pro- and anti-inflammatory cytokines T helper 1 (Th1: IFN-γ, TNF-α) and T helper 2 (Th2: IL-10) from Plasmodium berghei-infected mice treated with formulated ACEE in order to better characterize the mechanism behind ACEE's antimalarial activity. In addition, we have also determined the effect of formulated ACEE on parasite growth and liver function.

Methods

Balb/c mice were infected with P. berghei strain ANKA and then administered daily doses of ACEE at a dose of 20, 50, and 100 mg/kg BW, and survival time was recorded. We determined the presence of P. berghei strain ANKA and then administered daily doses of ACEE at a dose of 20, 50, and 100 mg/kg BW, and survival time was recorded. We determined the presence of P. berghei strain ANKA and then administered daily doses of ACEE at a dose of 20, 50, and 100 mg/kg BW, and survival time was recorded. We determined the presence of γ, TNF-α) and T helper 2 (Th2: IL-10) from

Results

We found that formulated ACEE inhibited parasite growth and showed the highest antimalarial activity at 100 mg/kg BW. AST and ALT levels were found to be in the normal range, and there was no significant difference among control and treatment groups (P > 0.05). Infected mice treated with formulated ACEE showed a significant increase in the production of IFN-γ, TNF-α) and T helper 2 (Th2: IL-10) from

Conclusion

This study suggests that the administration of ACEE was effective in inhibiting P. berghei strain ANKA and then administered daily doses of ACEE at a dose of 20, 50, and 100 mg/kg BW, and survival time was recorded. We determined the presence of γ, TNF-α) and T helper 2 (Th2: IL-10) from

Astrocaryum aculeatum fruit improves inflammation and redox balance in phytohemagglutinin-stimulated macrophages

ETHNOPHARMACOLOGICAL RELEVANCE

The fruit of Astrocaryum aculeatum G.Mey. (tucumã) is highly consumed by riverside communities in the Amazonian region. These communities have recently been shown to have increased longevity and reduced prevalence of age-related morbidity. Tucumã, which is locally used in their diet and traditional medicine may contribute to these features.

AIM OF THE STUDY

To investigate the anti-inflammatory and antioxidant properties of A. aculeatum extract against phytohemagglutinin-induced inflammation in cell cultures.

MATERIALS AND METHODS

Cell viability and cytotoxicity assays, gene expression of interleukins IL-1β, IL-6, IL-10, levels of reactive oxygen species (ROS), nitric oxide (NO) and thiols were employed, as well as the activities of antioxidant enzymes in RAW 264.7 cells stimulated with phytohemagglutinin to mimic inflammation.

RESULTS

The extract of A. aculeatum fruit inhibited macrophage proliferation (P < 0.05), arrested the cell cycle in G0/G1 phase (P < 0.001), increased antioxidant defenses (P < 0.01), reduced oxidative stress (P < 0.01), and modulated genes related to the inflammatory response (P < 0.001).

CONCLUSION

Our results demonstrate that A. aculeatum fruit has anti-inflammatory and antioxidant capacities. These beneficial effects of tucumã on cells are also likely to be seen in vivo, thereby suggesting that its extract is a suitable therapeutic adjuvant in the prevention or treatment of inflammatory diseases.

Effectiveness of amiodarone in treatment of cutaneous leishmaniasis caused by Leishmania major

Development of new chemotherapeutic agents is an essential issue in the treatment and control of a disease. This study aimed to evaluate the anti-leishmanial activity of amiodarone, an antiarrhythmic class III drug, against Leishmania major, the most prevalent etiological agent of cutaneous leishmaniasis in the old world. The proliferation of promastigotes and intracellular amastigotes in the absence or presence of amiodarone was estimated, in an in vitro study. For in vivo study, five weeks after infection of BALB/c mice with L. major, when the lesions appeared at the injection site, the mice were divided into four groups (n = 6 each); treatment was conducted for 28 consecutive days with vehicle, amiodarone at 40 mg/kg orally and glucantime at 60 mg/kg intraperitoneally. Therapy with amiodarone reduced the size of lesions compared to the untreated group after 12 days. Amiodarone decreased the parasite load and inflammatory responses, particularly the macrophages containing amastigotes, and enhanced granulation tissue formation in the dermis and subcutaneous area. The Tumor necrosis factor-α and Interleukin-6 levels were significantly lower in the cell culture supernatants of the inguinal lymph node in the amiodarone treated group compared to the vehicle and untreated groups. Amiodarone significantly increased the activity of glutathione peroxidase in comparison to the vehicle and untreated groups but did not affect the plasma levels of superoxide dismutase, malondialdehyde, adiponectin, and ferric reducing ability of plasma. Therefore, the anti- L. major activity and immunomodulatory effects of amiodarone reduced the parasitic load and enhanced wound healing in cutaneous leishmaniasis in BALB/c mice. Amiodarone reduced the lesion surface area, but it did not cure it completely.

Human macrophages and osteoclasts resorb β-tricalcium phosphate in vitro but not mouse macrophages

β-TCP is a resorbable bony biomaterial but its biodegradation mechanisms in vivo remains unclear. Osteoclast can resorb β-TCP but a role for macrophages has also been suggested by in vivo studies. However no in vitro study has clearly evidenced the action of macrophages in the resorption process. We prepared flat β-TCP tablets with a smooth surface to investigate the in vitro capability of murine (RAW 264.7) and human macrophage cells (PBMCs) to resorb the biomaterial. In parallel, these cells were differentiated into multinucleated osteoclasts with M-CSF and RANK-L. The action of these cells was evaluated by scanning electron microscopy and Raman microspectroscopy after a 21 day culture on the tablets. Human macrophages and osteoclasts derived from PBMCs appeared able to resorb β-TCP by forming resorption pits at the surface of the flat tablets. RAW macrophages were unable to resorb β-TCP but they exhibited this possibility when they have been differentiated into osteoclasts. These cells can engulf β-TCP grains in their cytoplasm as evidenced by light and TEM microscopy with production of carbonic anhydrase (revealed by the immunogold technique in TEM). The resorbed areas were characterized by severe degradation of the grains showing speckled and stick-like aspects indicating a chemical corrosion. The effect was maximal at the grain boundaries which have a slightly different chemical composition. Changes in the Raman spectrum were observed between the resorbed and un-resorbed β-TCP suggesting crystal modifications. In contrast, un-differentiated murine macrophages were not able to chemically attack β-TCP and no resorption pit was observed. RAW cell is not a representative model of the macrophage-biomaterial interactions that occur in human. This in vitro study evidences that both human osteoclasts and macrophages represent active cell populations capable to resorb β-TCP.

Evaluation of the anti-oxidant and anti-inflammatory effects of the methanolic extract of Ferula szowitsiana root on PHA-induced inflammation in human lymphocytes

Inflammation is defined as a defensive response of the body against either the endogenous or exogenous triggers, while this process becomes chronic leading to various disorders such as asthma, cancers, and multiple sclerosis. Recently, pharmacological properties of different constituents of F. szowitsiana have been reported. In the present study, we aimed to evaluate the anti-oxidative and anti-inflammatory effects of the methanolic extract of F. szowitsiana root on human isolated lymphocytes. The effects of either F. szowitsiana (10, 40 and 160 μg/ml) or dexamethasone (0.1 mM) were evaluated on the levels of cell proliferation, reactive oxygen species (ROS), nitric oxide (NO) production, malondialdehyde (MDA), superoxide dismutase (SOD) and catalase (CAT) activities, and total glutathione content (GSH) as well as the secretion of inflammatory cytokines [interleukin 6 (IL-6) and tumor necrosis factor (TNF)-α] in the presence or absence of phytohemagglutinin (PHA) stimulation (n = 8 for each group). PHA stimulation notably elevated ROS, NO, MDA, IL-6, and TNF-α levels as well as diminished GSH, CAT and SOD levels. In PHA-stimulated, the results also revealed that F. szowitsiana (10-160 µg/ml) significantly decreased MDA, ROS, NO, IL-6 and TNF-α levels as well as increased CAT, SOD and GSH levels. Collectively, F. szowitsiana is able to attenuate the overproduction of inflammatory and oxidative stress markers in the presence of PHA-stimulated T lymphocytes, while to propagate the anti-oxidative defense. Contextually, the plant has promising healing effects in the different inflammatory disorders associated with the interference of the acquired immune system such as multiple sclerosis and asthma.

Nutritional Modulation of Immune Function: Analysis of Evidence, Mechanisms, and Clinical Relevance

It is well-established that the nutritional deficiency or inadequacy can impair immune functions. Growing evidence suggests that for certain nutrients increased intake above currently recommended levels may help optimize immune functions including improving defense function and thus resistance to infection, while maintaining tolerance. This review will examine the data representing the research on prominent intervention agents n-3 polyunsaturated fatty acids (PUFA), micronutrients (zinc, vitamins D and E), and functional foods including probiotics and tea components for their immunological effects, working mechanisms, and clinical relevance. Many of these nutritive and non-nutritive food components are related in their functions to maintain or improve immune function including inhibition of pro-inflammatory mediators, promotion of anti-inflammatory functions, modulation of cell-mediated immunity, alteration of antigen-presenting cell functions, and communication between the innate and adaptive immune systems. Both animal and human studies present promising findings suggesting a clinical benefit of vitamin D, n-3 PUFA, and green tea catechin EGCG in autoimmune and inflammatory disorders, and vitamin D, vitamin E, zinc, and probiotics in reduction of infection. However, many studies report divergent and discrepant results/conclusions due to various factors. Chief among them, and thus call for attention, includes more standardized trial designs, better characterized populations, greater consideration for the intervention doses used, and more meaningful outcome measurements chosen.

The Immunomodulatory and Anti-Inflammatory Role of Polyphenols

This review offers a systematic understanding about how polyphenols target multiple inflammatory components and lead to anti-inflammatory mechanisms. It provides a clear understanding of the molecular mechanisms of action of phenolic compounds. Polyphenols regulate immunity by interfering with immune cell regulation, proinflammatory cytokines' synthesis, and gene expression. They inactivate NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells) and modulate mitogen-activated protein Kinase (MAPk) and arachidonic acids pathways. Polyphenolic compounds inhibit phosphatidylinositide 3-kinases/protein kinase B (PI3K/AkT), inhibitor of kappa kinase/c-Jun amino-terminal kinases (IKK/JNK), mammalian target of rapamycin complex 1 (mTORC1) which is a protein complex that controls protein synthesis, and JAK/STAT. They can suppress toll-like receptor (TLR) and pro-inflammatory genes' expression. Their antioxidant activity and ability to inhibit enzymes involved in the production of eicosanoids contribute as well to their anti-inflammation properties. They inhibit certain enzymes involved in reactive oxygen species ROS production like xanthine oxidase and NADPH oxidase (NOX) while they upregulate other endogenous antioxidant enzymes like superoxide dismutase (SOD), catalase, and glutathione (GSH) peroxidase (Px). Furthermore, they inhibit phospholipase A2 (PLA2), cyclooxygenase (COX) and lipoxygenase (LOX) leading to a reduction in the production of prostaglandins (PGs) and leukotrienes (LTs) and inflammation antagonism. The effects of these biologically active compounds on the immune system are associated with extended health benefits for different chronic inflammatory diseases. Studies of plant extracts and compounds show that polyphenols can play a beneficial role in the prevention and the progress of chronic diseases related to inflammation such as diabetes, obesity, neurodegeneration, cancers, and cardiovascular diseases, among other conditions.

Auraptene regulates Th1/Th2/TReg balances, NF-κB nuclear localization and nitric oxide production in normal and Th2 provoked situations in human isolated lymphocytes

BACKGROUND

Auraptene as member of dietary coumarins, is found in citrus fruits. Former studies have demonstrated its anti-inflammatory and anti-cancer activity.

PURPOSE

The mechanism of action and immune-modulatory property of this compound on human lymphocytes are greatly unknown.

STUDY DESIGN/METHODS

The effect of three concentrations (10, 30 and 90 µM) of auraptene or dexamethasone (0.1 mM) were evaluated on percentage of cell proliferation and nitric oxide (NO) production as well as secretion and gene expression of cytokines, and NF-κB level in PHA-stimulated and non-stimulated lymphocytes.

RESULTS

In non-stimulated cells, all three concentrations of auraptene significantly increased the gene expression index of IL-10 (P < 0.05-0.001). The IFN-γ gene expression index, IFN-γ/IL-4 and IL-10/IL-4 gene expression ratio were significantly increased due to the high concentration (90 µM) of auraptene treatment compared to control group (P < 0.05-0.001). In PHA stimulation, all three concentrations of the extract significantly decreased proliferation, cytokines (IL-4, IL-10 and IFN-γ) and NF-κB level as well as NO production, but IFN-γ/IL-4 and IL-10/IL-4 ratio were significantly increased compared control group (P < 0.05-0.001). Gene expression of IL-10 and IL-4 was decreased but that of IFN-γ as well as FN-γ/IL-4 and IL-10/IL-4 ratio were significantly increased due to all three concentrations of auraptene.

CONCLUSION

The results showed promoting effects of auraptene on T cell subsets toward Th₁ (IFN-γ) and T_reg (IL-10), which suggest its therapeutic value for treatment of Th₂ cells predominant diseases including allergic disease such as asthma and atopic dermatitis as well as cancers.

The isoprenoid end product N6-isopentenyladenosine reduces inflammatory response through the inhibition of the NFκB and STAT3 pathways in cystic fibrosis cells

Objective

N6-isopentenyladenosine (iPA) is an intermediate of the mevalonate pathway that exhibits various anti-cancer effects. However, studies on its anti-inflammatory activity are scarce and underlying molecular mechanisms are unknown. Therefore, we aimed to investigate the ability of iPA to exert anti-inflammatory effects in the human cystic fibrosis (CF) cell model of exacerbated inflammation.

Materials and methods

TNFα-stimulated CF cells CuFi-1 and its normal counterpart NuLi-1 were pre-treated with increasing concentrations of iPA and cell viability and proliferation were assessed by MTT and BrdU assays. The effect of iPA on IL-8 and RANTES secretion was determined by ELISA, and the activation and expression of signaling molecules and selenoproteins were studied by Western blot. To assess the direct effect of iPA on NFκB activity, luciferase assay was performed on TNFα-stimulated HEK293/T cells transfected with a NFκB reporter plasmid.

Results

We demonstrated for the first time that iPA prevents IL-8 and RANTES release in TNFα-stimulated CF cells and this effect is mediated by increasing the expression of the direct NFκB inhibitor IκBα and decreasing the levels of STAT3. Consistent with this, we showed that iPA inhibited TNFα-mediated NFκB activation in HEK/293T cells. Finally, we also found that iPA improved the levels of glutathione peroxidase 1 and thioredoxin reductase 1 only in CF cells suggesting its ability to maintain sufficient expression of these anti-oxidant selenoproteins.

Conclusions

Our findings indicate that iPA can exert anti-inflammatory activity especially in the cases of excessive inflammatory response as in CF.

In vitro antiviral, anti-inflammatory, and antioxidant activities of the ethanol extract of Mentha piperita L

The objective of this study is to investigate the antiviral, anti-inflammatory, and antioxidant effects of the ethanol extract of Mentha piperita L. leaves (MPE). M. piperita L. leaves were extracted by reflux with ethanol. Total phenolic acid and total flavonoid content were determined. The antiviral activity of MPE against the respiratory syncytial virus (RSV) and the anti-inflammatory activity were evaluated in vitro. The levels of key pre-inflammatory mediators and cytokines including nitric oxide (NO), tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, and prostaglandin E2 (PGE2) were determined. The antioxidant activities were also evaluated using a colorimetry method. MPE contained high levels of phenolic acid and flavonoid, showed antiviral activity against RSV with a high selectivity index, and significantly decreased the production of NO, TNF-α, IL-6, and PGE2 in lipopolysaccharide-stimulated RAW 264.7 cells. Meanwhile, MPE showed potential free-radical scavenging activities. These results indicate that Mentha piperita L. might be a good source of medicinal plants.

Effects of total flavonoids of sea buckthorn ( Hippophae rhamnoides L.) on cytotoxicity of NK92-MI cells

Sea buckthorn (Hippophae rhamnoides L.) has multifarious medicinal properties including immunoregulatory effect. The total flavonoids of Hippophae rhamnoides L. (TFH) are the main active components isolated from berries of sea buckthorn. The aim of this study was to evaluate the effects of TFH on the cytotoxicity of NK92-MI cells and its possible mechanisms. NK92-MI cells were treated with TFH (2.5 or 5.0 mg/L) or phosphate-buffered saline (PBS) for 24 h, the cytotoxicity against K562 was detected by measuring the release of lactate dehydrogenase (LDH), expression levels of NCRs (NKp30, NKp44, NKp46) and NKG2D were detected by flow cytometry, and expression levels of perforin and granzyme B were detected by western blot. Cytokine Antibody Arrays with 80 cytokine proteins were used to profile the effect of TFH on cytokines. Western blot was adopted to detect the effects of TFH on STAT1, STAT4, and STAT5 signal pathway. Compared with the normal control group, TFH could significantly enhance NK92-MI cell cytotoxicity against K562 cells, upregulate expressions of NKp44, NKp46, perforin, and granzyme B. TFH could upregulate expressions of IL-1α, IL-2, IL-7, IL-15, CSF-2, CSF-3, MCP-1, MIG, IFN-γ, TNF-α, and TNF-β and downregulate expressions of IL-16, MIP-1β, CX3CL-1, and MIF. TFH could increase expressions of phospho-STAT1 and phospho-STAT5. The results suggest that TFH stimulated NK92-MI cells to activate and enhance cytotoxicity of NK92-MI cells.

Grain and sweet sorghum (Sorghum bicolor L. Moench) serves as a novel source of bioactive compounds for human health

Grain sorghum is an important staple food crop grown globally while sweet sorghum is increasingly considered as a promising biofuel feedstock. Biofuels are the major economic products from the processing of large quantities of biomass, which is currently being utilized to make value-added products in the biorefinery approach. To date, these value-added products are typically commodity chemicals and waste materials used in agriculture. However, there are opportunities to generate high-value bioactive compounds from sorghum grain and biomass. Chronic diseases, such as cancers, are the top causes for morbidity and mortality in developed nations and are promoted by inflammation and oxidative stress. Globally, colorectal cancer results in approximately one-half million deaths annually. It is estimated that as much as 80% of colorectal cancer cases can be attributed to environmental and dietary factors. The sorghum grain and ligno-cellulosic biomass generated for biofuel production has been reported to be high in bioactive compounds, including phenolic acids and flavonoids, with antioxidant and anti-inflammatory properties. This review focuses on the bioactive compounds of grain and sweet sorghum (Sorghum bicolor L. Moench), for their anti-inflammatory, antioxidant, anti-colon cancer, and immune modulator functions. The review summarizes previous efforts to identify and quantify bioactive compounds in sorghum and documents their anti-cancer biological activities. Finally, this review discusses bioactive compound extraction methodologies and technologies as well as considerations for incorporating these technologies into current biorefining practices.

The Hydroalcoholic Extract Obtained from Mentha piperita L. Leaves Attenuates Oxidative Stress and Improves Survival in Lipopolysaccharide-Treated Macrophages

Mentha piperita L. (peppermint) possesses antimicrobial properties, but little is known of its ability to modulate macrophages. Macrophages are essential in bacterial infection control due to their antimicrobial functions and ability to link the innate and adaptive immune responses. We evaluated the effects of the peppermint leaf hydroalcoholic extract (LHAE) on cultured murine peritoneal macrophages stimulated or not with lipopolysaccharide (LPS) in vitro. Vehicle-treated cells were used as controls. The constituents of the extract were also identified. Epicatechin was the major compound detected in the LHAE. LPS-induced macrophage death was reversed by incubation with LHAE (1-30 μg/ml). Higher concentrations of the extract (≥100 μg/ml) decreased macrophage viability (49-57%) in the absence of LPS. LHAE (1-300 μg/ml) attenuated H₂O₂ (34.6-53.4%) but not nitric oxide production by these cells. At similar concentrations, the extract increased the activity of superoxide dismutase (15.3-63.5-fold) and glutathione peroxidase (34.4-73.6-fold) in LPS-treated macrophages. Only LPS-unstimulated macrophages presented enhanced phagocytosis (3.6-6.6-fold increase) when incubated with LHAE (3-30 μg/ml). Overall, the LHAE obtained from peppermint modulates macrophage-mediated inflammatory responses, by stimulating the antioxidant pathway in these cells. These effects may be beneficial when the excessive activation of macrophages contributes to tissue damage during infectious disease.

The Inhibitory Effect of Tartary Buckwheat Extracts on Adipogenesis and Inflammatory Response

Tartary buckwheat (Fagopyrum tataricum) has been established globally as a nutritionally important food item, particularly owing to high levels of bioactive compounds such as rutin. This study investigated the effect of tartary buckwheat extracts (TBEs) on adipogenesis and inflammatory response in 3T3-L1 cells. TBEs inhibited lipid accumulation, triglyceride content, and glycerol-3-phosphate dehydrogenase (GPDH) activity during adipocyte differentiation of 3T3 L1 cells. The mRNA levels of genes involved in fatty acid synthesis, such as peroxisome proliferator-activated receptor-γ (PPAR-γ), CCAAT/enhancer binding protein-α (CEBP-α), adipocyte protein 2 (aP2), acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), and stearoylcoenzyme A desaturase-1 (SCD-1), were suppressed by TBEs. They also reduced the mRNA levels of inflammatory mediators such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), monocyte chemoattractant protein 1 (MCP-1), and inducible nitric oxide synthase (iNOS). In addition, TBEs were decreased nitric oxide (NO) production. These results suggest that TBEs may inhibit adipogenesis and inflammatory response; therefore, they seem to be beneficial as a food ingredient to prevent obesity-associated inflammation.

In vitro antileishmanial activity of fisetin flavonoid via inhibition of glutathione biosynthesis and arginase activity in Leishmania infantum

With the increasing emergence of drug resistant Leishmania sp. in recent years, combination therapy has been considered as a useful way to treat and control of Leishmaniasis. The present study was designed to evaluate the antileishmanial effects of the fisetin alone and combination of fisetin plus Meglumine antimoniate (Fi-MA) against Leishmania infantum. The IC50 values for fisetin were obtained 0.283 and 0.102 μM against promastigotes and amastigote forms, respectively. Meglumine antimoniate (MA, Glucantime) as control drug also revealed IC50 values of 0.247 and 0.105 μM for promastigotes and amastigotes of L. infantum, respectively. In order to determine the mode of action of fisetin and Meglumine antimoniate (MA, Glucantime), the activities of arginase (ARG), catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD) were measured. Moreover, intracellular glutathione (GSH) and nitric oxide (NO) levels in L. infantum-infected macrophages and L. infantum promastigotes which were treated with IC50 concentrations of fisetin, MA and Fi-MA were investigated. Our results showed that MA decreased CAT and SOD activity and increased NO levels in L. infantum-infected macrophages. In promastigotes, MA inhibited parasite SOD activity and reduced parasite NO production. The decreased levels of most of the antioxidant enzymes, accompanying by the raised level of NO in treated macrophages with MA, were observed to regain their normal profiles due to Fi-MA treatment. Furthermore, fisetin could prevent the growth of promastigotes by inhibition of ARG activity and reduction of GSH levels and NO production. In conclusion, these findings showed that fisetin improves MA side effects.

Biotransformed citrus extract as a source of anti-inflammatory polyphenols: Effects in macrophages and adipocytes

Chronic non-communicable diseases such as obesity are preceded by increased macrophage infiltration in adipose tissue and greater secretion of pro-inflammatory cytokines. We evaluated the anti-inflammatory potential of Biotransformed extract, and two control extracts: In Natura and Autoclaved. The assays were performed using a cellular model with RAW264.7, 3T3-L1 cells, and RAW264.7 and 3T3-L1 co-culture. The innovation of the study was the use of Biotransformed extract, a unique phenolic extract of a bioprocessed citrus residue. LPS stimulated RAW264.7 cells treated with the Biotransformed extract exhibited lower secretion of TNF-α and NO and lower protein expression of NFκB. In RAW264.7 and 3T3-L1 co-culture, treatment with 1.0mg/mL of the Biotransformed extract reduced secretion of TNF-α (30.7%) and IL-6 (43.4%). Still, the Biotransformed extract caused higher increase in adiponectin in relation to control extracts. When the co-culture received a LPS stimulus, the Autoclaved extract at 1.0mg/mL reduced IL-6 and TNF-α concentrations, and raised adiponectin. However, it was noteworthy that the Biotransformed extract was also able to significantly reduce IL-6 concentration while the Natural extract was not. The Biotransformed citrus extract evaluated in this study showed anti-inflammatory activity in macrophages and in co-culture, indicating that bioprocess of citrus residue can contribute to new product development with anti-inflammatory potential.

The influence of hydro-ethanolic extract of Portulaca oleracea L. on Th1/Th2 balance in isolated human lymphocytes

ETHNOPHARMACOLOGICAL RELEVANCE

The anti-inflammatory and anti-oxidants activity of Portulaca oleracea L. (P. oleracea) were mentioned in traditional texts. In previous studies, different anti-inflammatory and anti-oxidant effects of P. oleracea were demonstrated. However, the mechanism of action and immunomodulatory property of this plant are greatly unknown. In the present study, the effect of the extract of this plant on IL-4, IL10, IFN-γ and T helper (h)1/Th2 balance in non-stimulated and stimulated human lymphocytes was examined.

MATERIALS AND METHODS

The effect of three concentrations (160, 40 and 10µg/ml) of P. oleracea or dexamethasone were evaluated on percentage of cell proliferation and nitric oxide (NO) production as well as secretion of cytokines (IL-4, IL10 and IFN-γ) in PHA-stimulated and non-stimulated lymphocytes, and compared to control and dexamethasone as positive control (n=15 for each group).

RESULTS

In stimulated cells, dexamethasone significantly inhibited the percentage of cell proliferation, NO production, and secretion of cytokines in comparison to control group (P<0.001 for all cases). The percentage of cell proliferation, NO production, and secretion of cytokines were significantly decreased while Th1/Th2 (IFN-γ/IL-4) and Treg/Th2 (IL-10/IL-4) balances significantly enhanced in treated groups with all three concentrations of extract compared to control group (P<0.001 for all cases). The effect of all concentrations of the extract on cell proliferation, NO production and secretion of cytokines as well as Treg/Th2 balance were significantly lower than dexamethasone (P<0.001 for all cases), but Th1/Th2 ratio obtained in the presence of only low extract concentration was lower than dexamethasone (P<0.01).

CONCLUSION

Different concentrations of extract promoted Th1/Th2 and Treg/Th2 balances which may suggest the therapeutic value of the plant in inflammatory disease associated with decreased Th1/Th2 balance such as asthma or cancers.

Structure-activity relationship of the inhibitory effects of flavonoids on nitric oxide production in RAW264.7 cells

We isolated flavonoids from herbal specimens from the Tibetan region (Sophora yunnanensis and Rhodiola sacra) that suppress nitric oxide (NO) production in macrophages stimulated by lipopolysaccharide and interferon-γ. The isolated flavonoids carry symmetric substitutions in the B ring (R_3'=R_5'). We analyzed the quantitative structure-activity relationship of the inhibitory activity by comparative molecular field analysis (CoMFA) using this series of flavonoids. Use of flavonoids with symmetrical substitutions in the B ring made it simpler to align molecules because it was not necessary to consider a huge number of combinations due to the B-ring conformation. The CoMFA model, whose cross-validated q² value was 0.705, suggested the existence of a hydroxy group at the 5-position, the choice of the A/C-ring scaffold (chromane or chromene) and electrostatic field around the B ring are important for NO inhibitory activity. Flavonoids synthesized based on the CoMFA model exhibited significant inhibitory potential against NO production, validating the predictive capability of the CoMFA model.

Diet and Inflammation in Alzheimer's Disease and Related Chronic Diseases: A Review

Inflammation is one of the pathological features of the neurodegenerative disease, Alzheimer's disease (AD). A number of additional disorders are likewise associated with a state of chronic inflammation, including obesity, cardiovascular disease, and type-2 diabetes, which are themselves risk factors for AD. Dietary components have been shown to modify the inflammatory process at several steps of the inflammatory pathway. This review aims to evaluate the published literature on the effect of consumption of pro- or anti-inflammatory dietary constituents on the severity of both AD pathology and related chronic diseases, concentrating on the dietary constituents of flavonoids, spices, and fats. Diet-based anti-inflammatory components could lead to the development of potent novel anti-inflammatory compounds for a range of diseases. However, further work is required to fully characterize the therapeutic potential of such compounds, including gaining an understanding of dose-dependent relationships and limiting factors to effectiveness. Nutritional interventions utilizing anti-inflammatory foods may prove to be a valuable asset in not only delaying or preventing the development of age-related neurodegenerative diseases such as AD, but also treating pre-existing conditions including type-2 diabetes, cardiovascular disease, and obesity.

Green tea EGCG, T-cell function, and T-cell-mediated autoimmune encephalomyelitis

Autoimmune diseases are common, disabling immune disorders affecting millions of people. Recent studies indicate that dysregulated balance of different CD4⁺ T-cell subpopulations plays a key role in immune pathogenesis of several major autoimmune diseases. Green tea and its active ingredient, epigallocatechin-3-gallate (EGCG), have been shown to modulate immune cell functions and improve some autoimmune diseases in animal models. In a series of studies we determined EGCG's effect on T-cell functions and its application in autoimmune diseases. We first observed that EGCG inhibited CD4⁺ T-cell expansion induced by polyclonal (mitogens or anti-CD3/CD28) or antigen-specific stimulation. We then showed that EGCG suppressed expansion and cell cycle progression of naïve CD4⁺ T by modulating cell cycle-related proteins. EGCG also inhibited naive CD4⁺ T-cell differentiation into Th1 and Th17 effector subsets by impacting their respective signaling transducers and transcription factors. These results suggest that EGCG may improve T-cell-mediated autoimmune diseases. Using the experimental autoimmune encephalomyelitis (EAE) mice, an animal model for human multiple sclerosis, we found that dietary supplementation with EGCG attenuated the disease's symptoms and pathology. These EGCG-induced changes are associated with findings in the immune and inflammation profiles in lymphoid tissues and the central nervous system: a reduction in proliferation of autoreactive T cells, production of proinflammatory cytokines, and Th1 and Th17 subpopulations, and an increase in regulatory T-cell populations. These results suggest that green tea or its active components may have a preventive and therapeutic potential in dealing with T-cell-mediated autoimmune diseases. However, the translational value of these findings needs to be validated in future human studies.

Anti-inflammatory effects of proanthocyanidin-rich red rice extract via suppression of MAPK, AP-1 and NF-κB pathways in Raw 264.7 macrophages

BACKGROUND/OBJECTIVES

Several pharmacological properties of red rice extract have been reported including anti-oxidant, anti-tumor, and reduced cancer cell invasion. This study was conducted to evaluate the anti-inflammatory effects of red rice extract on the production of inflammatory mediators in lipopolysaccharide (LPS)-induced Raw 264.7 macrophages.

MATERIALS/METHODS

Pro-inflammatory cytokines including tumor necrosis factor-α and interleukin-6 were determined by ELISA and cyclooxygenase-2 and inducible nitric oxide synthase expression was evaluated using western blot analysis. In addition, the signaling pathway controlling the inflammatory cascade such as nuclear factor kappa B (NF-κB), activator proteins-1 (AP-1), and mitogen-activated protein kinase (MAPK) was determined.

RESULTS

Our results showed that red rice polar extract fraction (RR-P), but not non-polar extract fraction, inhibited interleukin-6, tumor necrosis factor-α, and nitric oxide production in LPS-induced Raw 264.7 cells. RR-P also reduced the expression of inflammatory enzymes, inducible nitric oxide synthase, and cyclooxygenase-2. In addition, activation of AP-1 and NF-κB transcription factor in the nucleus was abrogated by RR-P. RR-P inhibited the phosphorylation of extracellular signaling-regulated kinase 1/2, c-Jun NH2-terminal kinase, and p38 MAPK signaling responsible for the expression of inflammatory mediators in LPS-stimulated Raw 264.7 cells. Based on chemical analysis, high amounts of proanthocyanidin and catechins were detected in the RR-P fraction. However, only proanthocyanidin reduced NF-κB and AP-1 activation in LPS-activated Raw 264.7 cells.

CONCLUSION

These observations suggest that the anti-inflammatory properties of RR-P may stem from the inhibition of pro-inflammatory mediators via suppression of the AP-1, NF-κB, and MAPKs pathways.

Advances and perspectives of colorectal cancer stem cell vaccine

Colorectal cancer is essentially an environmental and genetic disease featured by uncontrolled cell growth and the capability to invade other parts of the body by forming metastases, which inconvertibly cause great damage to tissues and organs. It has become one of the leading causes of cancer-related mortality in the developed countries such as United States, and approximately 1.2 million new cases are yearly diagnosed worldwide, with the death rate of more than 600,000 annually and incidence rates are increasing in most developing countries. Apart from the generally accepted theory that pathogenesis of colorectal cancer consists of genetic mutation of a certain target cell and diversifications in tumor microenvironment, the colorectal cancer stem cells (CCSCs) theory makes a different explanation, stating that among millions of colon cancer cells there is a specific and scanty cellular population which possess the capability of self-renewal, differentiation and strong oncogenicity, and is tightly responsible for drug resistance and tumor metastasis. Based on these characteristics, CCSCs are becoming a novel target cells both in the clinical and the basic studies, especially the study of CCSCs vaccines due to induced efficient immune response against CCSCs. This review provides an overview of CCSCs and preparation technics and targeting factors related to CCSCs vaccines in detail.

Phloridzin derivatives inhibiting pro-inflammatory cytokine expression in human cystic fibrosis IB3-1 cells

Cystic Fibrosis (CF) is the most diffuse autosomal recessive genetic disease affecting Caucasians. A persistent recruitment of neutrophils in the bronchi of CF patients contributes to exacerbate the airway tissue damage, suggesting that modulation of chemokine expression may be an important target for the patient's well being thus the identification of innovative anti-inflammatory drugs is considered a longterm goal to prevent progressive tissue deterioration. Phloridzin, isolated from Malus domestica by a selective molecular imprinting extraction, and its structural analogues, Phloridzin heptapropionate (F1) and Phloridzin tetrapropionate (F2), were initially investigated because of their ability to reduce IL-6 and IL-8 expression in human CF bronchial epithelial cells (IB3-1) stimulated with TNF-α. Release of these cytokines by CF cells was shown to be controlled by the Transcription Factor (TF) NF-kB. The results of the present investigation show that of all the derivatives tested, Phloridzin tetrapropionate (F2) is the most interesting and has greatest potential as it demonstrates inhibitory effects on the expression and production of different cytokines involved in CF inflammation processes, including RANTES, VEGF, GM-CSF, IL-12, G-CSF, MIP-1b, IL-17, IL-10 and IP-10, without any correlated anti-proliferative and pro-apoptotic effects.

Prunus yedoensis bark inhibits lipopolysaccharide-induced inflammatory cytokine synthesis by IκBα degradation and MAPK activation in macrophages

The bark of Prunus yedoensis is used in antitussive medicines and in oral herbal formulations for inflammatory skin disorders. In the present study, we explored whether P. yedoensis bark extract (PYE) and its solvent partitioned fractions could modulate lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-α and interleukin (IL)-6 in vivo and in vitro. In addition, we examined the effect of PYE extract and its fractions on LPS-induced NF-κB and mitogen-activated protein kinase (MAPK) signaling in mouse peritoneal macrophages. Oral treatment of PYE decreased serum levels of TNF-α and IL-6 in LPS injected mice. PYE inhibited LPS-induced TNF-α and IL-6 in macrophages at the transcriptional level and also suppressed LPS-induced IκBα degradation and MAPK activation in vitro. Among the fractions, the chloroform fraction, which contains genistein, naringenin, sakuranetin, prunetin, and amygdalin, showed inhibitory effects at much lower concentrations than the water and ethyl acetate fractions. Taken together, our results indicate that PYE was able to inhibit LPS-induced expression of TNF-α and IL-6, the latter of which was more prominent. The effects of PYE on inflammatory cytokine synthesis may involve modulation of NF-κB and MAPK activation.

Antioxidant and anti-inflammatory activity of Ocimum labiatum extract and isolated labdane diterpenoid

Background

Plants from the genus Ocimum are used as folk medicine for treating various diseases including inflammatory and immune-related diseases. Numerous reports have suggested plant extracts and their constituents as possible anti-inflammatory agents. Here, in vitro evidence of Ocimum labiatum’s immune-enhancing and antioxidant properties is presented for the first time.

Methods

The anti-inflammatory effect of O. labiatum ethanolic extract and an isolated diterpenoid was determined using a cytometric bead array (CBA) technique. The effect on phytohemagglutinin (PHA)-induced nitric oxide (NO) production in peripheral blood mononuclear cells (PBMCs) was also assessed. A battery of antioxidant assays were used for detecting antioxidant activity while the anti-inflammatory mechanism was evaluated using an ELISA-based activator protein (AP-1) (c-Jun) assay. Cytotoxicity was determined on TZM-bl and PBMCs using a tetrazolium dye and confirmed by a novel label-free real-time assay.

Results

A 25 μg/mL non-cytotoxic concentration of O. labiatum extract significantly (p < 0.05) inhibited the production of pro-inflammatory cytokines; IL-2, IL-4, IL-6 and IL-17A. Except for the dual acting pro- or anti-inflammatory cytokine, IL-6, which was upregulated, a non-cytotoxic 50 μM concentration of the isolated labdane diterpenoid compound significantly (p < 0.05) decreased the production of all the pro-inflammatory cytokines. In the anti-inflammatory pathway studies, the compound also inhibited AP-1 significantly (p < 0.05) at 50 μM. The extract demonstrated strong, dose dependent antioxidant activity with IC₅₀ values ranging from 13 ± 0.8 to 54.86 ± 1.28 μg/mL while the terpene had no antioxidant property. The extract and diterpenoid decreased the production of the inflammatory mediator NO, at non-cytotoxic concentrations. The CC₅₀ of the extract in TZM-bl and PBMCs was 62.6 ± 0.6 and 30.1 ± 0.4 μg/mL while that of the compound was 112.6 ± 0.2 and 70 ± 0.4 μM respectively. The real time studies confirmed tetrazolium dye assessed viability and also detected a unique growth pattern for the plant materials compared to untreated cells.

Conclusions

O. labiatum extract demonstrated promising anti-inflammatory and antioxidant properties while the terpenoid showed anti-inflammatory but no antioxidant activity. The anti-inflammatory mechanism of the terpene was a result of inhibition of AP-1. These data represents promising first steps towards the development of naturally derived anti-inflammation drugs.