Anti-stress action of an orally-given combination of resveratrol, ß-glucan, and vitamin C.

Stress has repeatedly been found to reduce the abilities of the immune system to fight against individual attacks. The current dissatisfaction with classical medications has led to more attention being focused on natural molecules. As recent studies have suggested that some bioactive molecules can have synergistic effects in stimulation of immune system and reduction of stress, we have evaluated the stress-reducing effects of the resveratrol-ß-glucan-vitamin C combination. We found that compared to its individual components, this combination was the strongest reducer of stress-related symptoms, including corticosterone levels and IL-6, IL-12 and IFN-γ production.

Anti-infectious and Anti-tumor Activities of ß-glucans.

BACKGROUND/AIM: The aim of this study was to directly compare the anti-infectious and anti-cancer effects of five commercially available glucans. MATERIALS AND METHODS: We used five different glucans isolated from algae, yeast, bacteria, oat, and mushroom. We compared their effects on the stimulation of phagocytosis of blood cells, on the secretion of IL-2, and on the inhibition of melanoma and breast and lung cancers. In addition, we evaluated the effects of glucan supplementation on two experimental models of infection. RESULTS: Most of the tested glucans stimulated phagocytosis and IL-2 secretion, reduced cancer growth, and ameliorated some effects of experimental infections. CONCLUSION: Glucans can produce significant pleiotropic effects, but the activity varies among individual samples.

Enhancing effects of new biological response modifier beta-1,3 glucan sulfate PS3 on immune reactions.

Glucans have a long history as non-specific biological modulators; however, but the search for optimal chemical configuration is still on. The objective of this study was to evaluate intraperitoneal application of PS3, a sulfated derivative of a (1-->3)-beta-D-glucan isolated from sporophytes of Laminaria digitata. PS3 showed significant stimulation of phagocytic activity as well as potentiation of synthesis and release of IL-2 by splenocytes. In addition, PS3 increased NK cell-mediated killing of tumor cells both in vitro and in vivo. When combined, our observations suggest that PS3 is similarly effective as native non-sulfated (1-->3)-beta-D-glucan and is generally more active than lentinan.

Glucans and Cancer: Comparison of Commercially Available ß-glucans - Part IV.

BACKGROUND/AIM: ß-Glucans are well-established immunomodulators with strong effects across all immune reactions. Due to the extensive amount of studies, glucans are steadily progressing from a non-specific immunomodulator to a licensed drug. However, direct comparisons of higher numbers of different glucans are rare. MATERIALS AND METHODS: In this study, we used 16 different glucans isolated from yeasts, mushroom, algae, and oat and compared their effects on phagocytosis, IL-2 production, antibody secretion, and inhibition of three experimental cancer models. RESULTS: Our results showed significant differences among tested glucans, showing that despite the fact that glucans in general have strong stimulating effects on most aspects of the immune system, it is necessary to choose the right glucan. CONCLUSION: Based on our studies, we can conclude that highly purified and active glucans have significant pleiotropic effects.

Combination Therapy with Glucan and Coenzyme Q10 in Murine Experimental Autoimmune Disease and Cancer.

BACKGROUND/AIM: Coenzyme Q10 is a well-accepted anti-oxidant agent known to play a protective role in various physiological and disease processes. Recently, Coenzyme Q10 is gaining attention as a substance with significant anti-inflammatory properties. ß-Glucan is the most studied immunomodulator with significant synergetic effects with numerous bioactive molecules. We aimed to evaluate the possible synergistic effects of simultaneous use of coenzyme Q10 with the well-established immune modulator, ß-glucan, on immune reactions and cancer development. MATERIALS AND METHODS: Coenzyme Q10 and ß-glucan were used, both in vivo and in vitro, and their effects were evaluated using phagocytosis and cytokine secretion. RESULTS: Our study confirmed the strong anti-inflammatory effects of coenzyme Q10 and showed that these effects were further potentiated with the addition of ß-glucan. The anticancer effects of coenzyme Q10 were less pronounced, but stronger, with the addition of ß-glucan. CONCLUSION: There is significant synergy between coenzyme Q10 and ß-glucan.

Procathepsin D secreted by HaCaT keratinocyte cells - A novel regulator of keratinocyte growth.

Procathepsin D (pCD), the precursor form of lysosomal aspartic protease, is overexpressed and secreted by various carcinomas. The fact that secreted pCD plays an essential role in progression of cancer has been established. In this study, we describe substantial secretion of pCD by the human keratinocyte cell line HaCaT, under serum-free conditions. Moreover, exogenous addition of purified pCD enhanced the proliferation of HaCaT cells. The proliferative effect of pCD was inhibited by a monoclonal antibody against the activation peptide (AP) of pCD. Treatment of HaCaT cells with pCD or AP led to the secretion of a set of cytokines that might promote the growth of cells in a paracrine manner. The role of secreted pCD and its mechanism of action were studied in a scratch wound model and the presence of pCD and AP enhanced regeneration, while this effect was reversed by the addition of anti-AP antibody. Expression and secretion of pCD was upregulated in HaCaT cells exposed to various stress conditions. Taken together, our results strongly suggest that the secretion of pCD is not only linked to cancer cells but also plays a role in normal physiological conditions like wound healing and tissue remodeling.

Secretion of cytokines in breast cancer cells: the molecular mechanism of procathepsin D proliferative effects.

Procathepsin D (pCD) is a major secreted protein in estrogen receptor-positive (ER+) breast cancer cell lines. Several independent studies have documented pronounced mitogenic effect of secreted pCD on cancer tissue-derived cell lines, including those from breast, lung, and prostate cancer. It has also been shown that the proliferative effect of pCD involves both autocrine and paracrine modes of action. Recent studies have suggested that pCD could act as a key paracrine communicator between cancer and stromal cells. We have shown earlier that the proliferative activity of pCD depends on the activation peptide sequence of pCD. The present study casts light on the mechanism by which pCD influences the proliferation of cancer cells expressing the ER. Results described in the current paper clearly show that pCD initiates secretion of cytokines interleukin-4 (IL-4), IL-8, IL-10, IL-13, macrophage inflammatory protein-1beta and (MIP-1beta) from such tumor cells. Secreted cytokines take part in the proliferation of the cancer cells, as proven by selective inhibition using antibodies. In addition, expression of cytokine receptors on tested cell lines corresponded to the effects of individual cytokines. An analogous pattern was also observed for fibroblasts, which, under physiologic conditions, are the cells in closest contact with the tumor tissue and play a role in tumor growth and invasion. Our observations were further supported by coculture experiments that are in agreement. Although very similar in response to addition of pCD, the invasive ER- cells do not secrete cytokines. Together with previous in vivo results, these data point to pCD as one of key molecules for therapeutic attack in breast cancer.

Procathepsin D expression correlates with invasive and metastatic phenotype of MDA-MB-231 derived cell lines.

Procathepsin D (pCD) is a glycoprotein secreted abundantly by cancerous cells with a documented role in tumor development. The levels of pCD in primary tumors are highly correlated with an increased incidence of metastasis. Our earlier studies have shown that pCD exerts its effect on cancer cells through its activation peptide (AP) and involves both autocrine and paracrine modes of action. In this study, we analyzed the expression and role of pCD in MDA-MB-231 and its derived cell lines 1833 and 4175 possessing discrete metastatic abilities. Our results demonstrated a direct relationship between expression and secretion of pCD to the differential invasive potential of these cells. Also, the cell lines responded to AP treatment by enhancing their invasive potential, proliferation and induction of secretion of various cytokines, suggesting that pCD plays a role in metastasis through its AP region.

Orally administered marine (1-->3)-beta-D-glucan Phycarine stimulates both humoral and cellular immunity.

(1-->3)-beta-D-Glucans represent highly conserved structural components of cell walls in yeast, fungi, or seaweed. However, it is still unknown how they mediate their effects. The aim of this study was to evaluate both intraperitoneal and oral application of seaweed-derived (1-->3)-beta-D-glucan Phycarine. Phycarine showed significant stimulation of phagocytosis by peripheral blood cells. In addition, the efficiency of chemotherapy of Lewis lung carcinoma with cyclophosphamide was potentiated by Phycarine administration. Phycarine also strongly shortened the recovery of leucopenia caused either by chemotherapy or irradiation. Besides the role in stimulation of cellular immunity, we also found a significant increase of antibody formation. Using a suckling rat model for evaluation of the absorption and tissues distribution of enterally administered (125)I-Phycarine, we found that the majority of Phycarine was detected in the stomach and duodenum 5 min after the administration. This amount sharply decreased during first 30 min. A significant amount of Phycarine entered proximal intestine in a shortly after the gavage. Its transit through proximal intestine was decreasing with time and simultaneously increasing in the ileum. Systemic blood levels were very low (less than 0.5%). Taken together, these observations suggest that Phycarine is similarly effective both after i.p. and oral application, has very strong stimulating effects on three types of experimentally induced leucopenia and stimulates both humoral and cellular branch of immune reactions. The majority of Phycarine can be detected throughout the gastrointestinal tract, supporting the feasibility of enteral administration of Phycarine in the treatment of gastrointestinal diseases.

Glucan and resveratrol complex--possible synergistic effects on immune system.

BACKGROUND: Recent data showing that glucan elicited defense responses in grapevine and induced protection via induction of resveratrol production led us to evaluate the possible synergetic effects of glucan and resveratrol complex on immune reactions. METHODS: We measured phagocytosis using HEMA particles, expression of cell surface markers via fl ow cytometry, expression of cytokines using ELISA, recovery after fluorouracil-induced leucopenia and effects on gene expression via RT-PCR. RESULTS: Our results showed that both glucan and resveratrol complex stimulated phagocytosis of blood leukocytes, caused increase in surface expression of CD(+) splenocytes and showed higher restoration of spleen recovery after experimentally induced leucopenia. In all these cases, strong synergetic effects were observed. When we measured the effects of these substances on expression level of NF-kappaB2, Cdc42 and Bcl-2 in breast cancer cells, upregulation of Cdc42 expression was evident only using both immunomodulators in combination. CONCLUSIONS: In conclusion, our data suggest significant synergy in stimulation of immune reactions and support further studies of these natural immunomodulators.

Fucoidans Stimulate Immune Reaction and Suppress Cancer Growth.

BACKGROUND/AIM: Fucoidans are gaining popularity as natural immunomodulators. The aim of this study was to compare the immunological activities or both purified samples and commercially available mixtures containing fucoidan. MATERIALS AND METHODS: We evaluated the effects of various samples on phagocytosis, mitogenic response, natural killer (NK) activity, antibody formation and inhibition of breast cancer growth. RESULTS: We found significant immunostimulating activity, but the strength of these effects was different among individual samples. CONCLUSION: Fucoidans have strong immunostimulating potential, including inhibition of cancer, with isolated samples offering better activity than commercial mixtures.

Essential Oils from Thyme (Thymus vulgaris): Chemical Composition and Biological Effects in Mouse Model.

Thymus species are popular spices and contain volatile oils as main chemical constituents. Recently, plant-derived essential oils are gaining significant attention due to their significant biological activities. Seven different thymus-derived essential oils were compared in our study. First, we focused on their chemical composition, which was followed up by testing their effects on phagocytosis, cytokine production, chemotaxis, edema inhibition, and liver protection. We found limited biological activities among tested oils, with no correlation between composition and biological effects. Similarly, no oils were effective in every reaction. Based on our data, the tested biological use of these essential oils is questionable.

Addition of Selenium Improves Immunomodulative Effects of Glucan.

BACKGROUND: Selenium (Se) is an established essential nutrient that plays a role in various biological processes including cancer development. Similarly, stimulation of immune reactions by ß-glucans is well-documented. AIMS: In the current study, we focused on the stimulation of phagocytosis and interleukin (IL)-2 production and on potentiation of anticancer immunity by a combination of glucan with two types of Se. MATERIALS AND METHODS: Phagocytosis was evaluated using synthetic microspheres; cancer development was measured either using breast cancer cells or using lung cancer cells. RESULTS: Using two different murine models of cancer, we showed that the Se/glucan combination strongly suppressed the growth of cancer, mostly probably via stimulation of immunity. CONCLUSIONS: A combination of glucan with Se offers superior stimulation of immunity and inhibition of cancer growth.

Effects of curcumin on Helicobacter pylori infection.

BACKGROUND: Curcumin is a well-established natural molecule with significant biological and pharmaceutical effects. Its effects on Helicobacter pylori (H. pylori) infection have been repeatedly confirmed both in animal and human models. This study directly compared five different samples to evaluate if the effects are general or if they differ among samples. METHODS: Using a mouse model, we studied the effects of curcumin on lipid peroxide (LPO) level, myeloperoxidase (MPO) and urease activity, number of colonized bacteria, levels of anti-H. pylori antibodies, biofilm formation, IFN-γ, IL-4, gastrin and somatostatin levels in serum, and minimum inhibitory concentration. In addition, we evaluated the effects on biofilm production and antibacterial antibody response. RESULTS: In all tests, one sample (Sabinsa) was consistently the most active. CONCLUSIONS: All curcumin samples showed some anti-H. pylori effects, but only some of the tested samples had significant activity.

Glucan Supplementation Has Strong Anti-melanoma Effects: Role of NK Cells.

ß-Glucan is a natural immunomodulator consisting of glucose molecules. It is a well-established modifier with significant beneficial properties in infectious diseases and cancer therapy. Glucan effects on melanoma are relatively less studied, despite the increasing incidence of this type of cancer. In the current study, we focused on possible effects of insoluble yeast-derived ß-glucan on the growth of melanoma cells. We found that glucan supplementation had a strong-positive effect in both reducing tumor weight, lung colonies and overall survival rate of tested animals. In addition, glucan inhibited the damage to blood cells and potentiated the effects of regular chemotherapy. By using depletion of natural killer (NK) cells, we showed that these effects are, at least partly, mediated by direct action of glucan on NK cells.

Glucan supplementation enhances the immune response against an influenza challenge in mice.

BACKGROUND: The strong immunostimulating potential of ß-glucans has been well established in numerous diseases. However, the effects on viral infection were less studied. METHODS: In our study, we focused on possible effects of a special combined glucan formulation on immunosuppression caused by influenza infection. RESULTS: We found that a 2-week oral feeding with glucan mixture significantly reduced the effects of influenza infection in total mortality. Our study was focused on phagocytosis, cytokine levels, antibody response and cytotoxicity assay. CONCLUSIONS: Based on our data, we concluded that these effects are caused by stimulation of both cellular and humoral immune reaction resulting in lower viral load.

Role of enzymatically inactive procathepsin D in lung cancer.

Procathepsin D is over-secreted by some human cancer cells. This enzymatically inactive precursor has been established as playing an important role in the development of several types of cancer. In the present investigation, we used both the isolated human procathepsin D and a synthetic 44 amino acid peptide corresponding to the activation peptide of procathepsin D to test their effects on the proliferation of lung cancer cells. We showed that both the procathepsin D and the activation peptide act as growth factors. In parallel, we also measured the secretion of procathepsin D by lung cancer cells and compared the secretion with invasiveness through Matrigel membrane. Our findings represent the first experimental data showing the direct effects of procathepsin D and its activation peptide on growth and invasiveness of lung cancer cells.

Cytokines affect procathepsin D-stimulated proliferation of breast cancer cells.

Procathepsin D is over secreted by certain human cancer cells. This enzymatically inactive precursor has been established as playing an important role in the development of several types of cancer. Due to their pleiotropical effects, numerous cytokines have also been recognized as important immunotherapeutic agents. In this study, we focused on the role of IL-4, IL-10 and IL-13 on procathepsin D-stimulated proliferation of breast cancer cells. Our results clearly showed that only ER+ breast cancer cells responded to the presence of cytokines by proliferation; ER- cells were resistant to the addition of cytokines. Since addition of anti-procathepsin D antibodies blocked the growth potentiation, we concluded that addition of these cytokines resulted in stimulation of synthesis and/or release of procathepsin D. This conclusion was further supported by findings of procathepsin D in culture supematants of cells incubated with cytokines.

Immune-enhancing effects of Maitake (Grifola frondosa) and Shiitake (Lentinula edodes) extracts.

BACKGROUND: The role of glucan in stimulation of immune reactions has been studied for several decades. In this report, we focused on the effects of orally administered glucan Maitake and Shiitake on immune reactions. MATERIALS AND METHODS: We measured phagocytosis, NK cell activity, and secretion of IL-6, IL-12, IFN-γ as well as C-reactive protein (CRP) after 14 days of oral application of tested glucans. For comparison, active hexose correlated compound (AHCC) was used in all reactions. RESULTS: We found significant stimulation of defense reaction. In all cases, the most active was the Maitake-Shiitake combination, with Maitake alone being the second strongest, followed by Shiitake on its own and AHCC. CONCLUSIONS: Short-term oral application of natural immunomodulating glucans from Maitake and Shiitake mushrooms strongly stimulated both the cellular and humoral branch of immune reactions. These activities were significantly higher than those of AHCC.

Natural immunomodulators and their stimulation of immune reaction: true or false?

Natural immunomodulators are getting more and more popular. The popularity, however, often brings over-optimistic claims and mediocre effects. The purpose of the present study was to directly compare eleven most commonly used immunomodulators. Through testing both cellular and humoral branches of immune reactions, we found that most of the immunomodulators tested have limited, if any, effects, with glucan being consistently the most active molecule strongly stimulating every reaction evaluated. These data were also confirmed using a Lewis lung cancer model, where only glucan and resveratrol lowered the number of metastases.