Th1/Th2 cytokine production by clove-treated mice

Egg Yolk Protein Water Extracts Modulate the Immune Response in BALB/c Mice with Immune Dysfunction Caused by Forced Swimming

The objective of this study was to determine the immunomodulatory effects of egg yolk protein–water extract (EYW) on splenocyte proliferation, cytokine secretion, immunoglobulin production, and NK cell cytotoxic activity in BALB/c mice. The forced swimming test (FST) was used to provide a model for suppressing immune regulation. The proliferation of B cells in the EYW supplementation group was significantly increased from the level to which it was reduced by the FST (from 40.9% to 81.8%, p < 0.05). EYW supplementation affected cytokine secretion of splenocytes. Levels of interleukin (IL)-2 and IL-10—as Th1 and Th2 cytokines, respectively—were decreased after the FST. However, EYW supplementation showed that secretion levels of these cytokines were significantly increased to pre-FST levels (p < 0.05). The production of immunoglobulins (IgA and IgG) was increased abnormally after the FST, whereas EYW supplementation significantly decreased it to pre-FST levels (p < 0.05). EYW supplementation also improved NK cell cytotoxic activity against YAC-1 tumor cells compared to the PC group (p < 0.05). These data suggest that EYW has potential as an immunomodulatory agent in the food and/or pharmaceutical industries.

Plant-Derived Nutraceuticals and Immune System Modulation: An Evidence-Based Overview

Immunomodulators are agents able to affect the immune system, by boosting the immune defences to improve the body reaction against infectious or exogenous injuries, or suppressing the abnormal immune response occurring in immune disorders. Moreover, immunoadjuvants can support immune system acting on nonimmune targets, thus improving the immune response. The modulation of inflammatory pathways and microbiome can also contribute to control the immune function. Some plant-based nutraceuticals have been studied as possible immunomodulating agents due to their multiple and pleiotropic effects. Being usually more tolerable than pharmacological treatments, their adjuvant contribution is approached as a desirable nutraceutical strategy. In the present review, the up to date knowledge about the immunomodulating properties of polysaccharides, fatty acids and labdane diterpenes have been analyzed, in order to give scientific basic and clinical evidence to support their practical use. Since promising evidence in preclinical studies, limited and sometimes confusing results have been highlighted in clinical trials, likely due to low methodological quality and lacking standardization. More investigations of high quality and specificity are required to describe in depth the usefulness of these plant-derived nutraceuticals in the immune system modulation, for health promoting and disease preventing purposes.

Anti-inflammatory effect of dietary pork extract on proliferation and cytokine secretion using mouse primary splenocytes

The anti-inflammatory effects of boiled pork meat (BPM) and hot water extracts of pork meat (WPM) on splenocyte proliferation and T cell cytokine regulation in BALB/c mice were evaluated. The proliferation of splenocytes in high concentration WPM groups was significantly higher than the control stimulated by LPS and Con A. In the white blood cells, WPM groups had significantly higher counts of lymphocytes and lower counts of neutrophils than the control (p<0.05). The Th1 (IFN-γ, TNF-α, IL-2) and Th2 (IL-4, IL-5, IL-10) cytokine levels in high-concentration WPM groups were higher than those in the control. In addition, TNF-α/IL-10 and IL-2/IL-4 secretions of splenocytes in the high concentration WPM group with LPS or Con A treatment was significantly lower than the control (p<0.05). Therefore, this study suggested that high concentration of WPM had anti-inflammatory effects on the primary splenocyte, which indicating that water extracts of pork meat can enhance the immune system of mice.

Clove (Syzygium aromaticum) ingredients affect lymphocyte subtypes expansion and cytokine profile responses: An in vitro evaluation

Clove (Syzygium aromaticum) has been used in folk medicine in many disorders. The present work aimed to investigate effects of clove essential oil as eugenol and water soluble ingredients on mouse splenocytes. Clove extracts were harvested and in different concentrations (0.001–1000 μg/mL) were affected to splenocytes and also phytohemagglutinin (PHA = 5 μg/mL) and lipopolysaccharide (LPS = 10 μg/mL) activated splenocytes; then splenocytes proliferation assayed using the MTT ([3-(4, 5-dimethylthiazole-2-yl)-2, 5-diphenyl tetrazolium bromide]) method were done. On the culture supernatant interferon (IFN)-γ, interleukin (IL)-4, IL-10, and transforming growth factor (TGF)-β cytokines were measured. Clove ingredients (100 μg/mL and 1000 μg/mL) reduced PHA stimulated splenocytes proliferation and enhanced LPS stimulated cells expansion. Treated splenocytes showed suppression of IFN-γ release and induction of IL-4, IL-10, and TGF-β secretion (in the range of 0.1–1000 μg/mL). The results of this study suggest clove extracts could suppress the T cell cellular immunity and enhance humoral immune responses. In clove affection cytokine pattern shifted toward modulatory and Th2 responses and accelerator of humoral immunity cytokines.

Clove and eugenol in noncytotoxic concentrations exert immunomodulatory/anti-inflammatory action on cytokine production by murine macrophages

OBJECTIVES

The extract and essential oil of clove (Syzygium aromaticum) are widely used because of their medicinal properties. Eugenol is the most important component of clove, showing several biological properties. Herein we have analysed the immunomodulatory/anti-inflammatory effect of clove and eugenol on cytokine production (interleukin (IL)-1β, IL-6 and IL-10) in vitro.

METHODS

Macrophages were incubated with clove or eugenol (5, 10, 25, 50 or 100µg/well) for 24h. Concentrations that inhibited the production of cytokines were used before or after incubation with lipopolysaccharide (LPS), to verify a preventive or therapeutic effect. Culture supernatants were harvested for measurement of cytokines by enzyme-linked immunosorbent assay.

KEY FINDINGS

Clove (100µg/well) inhibited IL-1β, IL-6 and IL-10 production and exerted an efficient action either before or after LPS challenge for all cytokines. Eugenol did not affect IL-1β production but inhibited IL-6 and IL-10 production. The action of eugenol (50 or 100µg/well) on IL-6 production prevented efficiently effects of LPS either before or after its addition, whereas on IL-10 production it counteracted significantly LPS action when added after LPS incubation.

CONCLUSIONS

Clove exerted immunomodulatory/anti-inflammatory effects by inhibiting LPS action. A possible mechanism of action probably involved the suppression of the nuclear factor-κB pathway by eugenol, since it was the major compound found in clove extract.