Peptide immunomodulators versus infection; an analysis

Kaurenoic acid nanocarriers regulates cytokine production and inhibit breast cancer cell migration

Breast cancer is the type of cancer with the highest incidence in women around the world. Noteworthy, the triple-negative subtype affects 20% of the patients while presenting the highest death rate among subtypes. This is due to its aggressive phenotype and the capability of invading other tissues. In general, tumor-associated macrophages (TAM) and other immune cells, are responsible for maintaining a favorable tumor microenvironment for inflammation and metastasis by secreting several mediators such as pro-inflammatory cytokines IL-1β, IL-6, and TNF-α, chemokines like CCL2, and other proteins, as metalloproteinases of matrix (MMP). On the other hand, immunomodulatory agents can interfere in the immune response of TAM and change the disease prognosis. In this work, we prepared nanostructured lipid carriers containing kaurenoic acid (NLC-KA) to evaluate the effect on cytokine production in vitro of bone marrow-derived macrophages (BMDM) and the migratory process of 4 T1 breast cancer cells. NLC-KA prepared from a blend of natural lipids was shown to have approximately 90 nm in diameter with low polydispersity index. To test the effect on cytokine production in vitro in NLC-KA treated BMDM, ELISA assay was performed and pro-inflammatory cytokines IL-1β, IL-6, and TNF-α were quantified. The formulation reduced the secretion of IL-1β and TNF-α cytokines while presenting no hemolytic activity. Noteworthy, an anti-migratory effect in 4 T1 breast cancer cells treated with NLC-KA was observed in scratch assays. Further, MMP9 and CCL2 gene expressions in both BMDM and 4 T1 treated cells confirmed that the mechanism of inhibition of migration is related to the blockade of this pathway by KA. Finally, cell invasion assays confirmed that NLC-KA treatment resulted in less invasiveness of 4 T1 cells than control, and it is independent of CCL2 stimulus or BMDM direct stimulus. Ultimately, NLC-KA was able to regulate the cytokine production in vitro and reduce the migration of 4 T1 breast cancer cells by decreasing MMP9 gene expression.

Review of recently used techniques and materials to improve the efficiency of orally administered proteins/peptides

OBJECTIVES

The main objective of present review is to explore and evaluate the effectiveness of recently developed methods to improve the bioavailability of orally administered biopharmaceutical drugs.

METHODS

A systematic search of sciencedirect, tandfonline and Google Scholar databases based on various sets of keywords was performed. All results were evaluated based on their abstracts, and irrelevant studies were neglected during further evaluation.

RESULTS

At present, biopharmaceuticals are used as injectable therapies as they are not absorbed adequately from the different routes of drug administration, particularly the oral one. Their insufficient absorption is attributed to their high molecular weight, degradation by proteolytic enzymes, high hydrophilicity and rigidity of the absorptive tissues. From industrial aspect incorporation of enzyme inhibitors (EIs) and permeation enhancers (PEs) and mucoadhesive polymers into conventional dosage forms may be the easiest way of formulation of orally administered macromolecular drugs, but the effectiveness of protection and absorption enhancement here is the most questionable. Conjugation may be problematic from regulatory aspect. Encapsulation into lipid-based vesicles sufficiently protects the incorporated macromolecule and improves intestinal uptake but have considerable stability issues. In contrast, polymeric nanocarriers may provide good stability but provides lower internalization efficacy in comparison with the lipid-based carriers.

CONCLUSION

It can be concluded that the combination of the advantages of mucoadhesive polymeric and lid-based carriers in hybrid lipid/polymer nanoparticles may result in improved absorption and might represent a potential means for the oral administration of therapeutic proteins in the near future. Graphical abstract Delivery systems for oral protein daministration.

A strong CD8+ T cell-stimulating supramolecular hydrogel

The development of molecules with immune stimulatory properties is crucial for cancer immunotherapy. In this work, we combined two peptide-based molecules, tuftsin (TKPR) and Nap-GDFDFDY, to develop a novel self-assembling molecule Nap-GDFDFDYTKPR (Comp.3), which has strong CD8+ T cell stimulatory properties. Comp.3 could self-assemble into nanofibers and hydrogels, which significantly improved the stability of tuftsin against enzyme digestion. The nanofibers of Comp.3 enhanced the phagocytic activity of macrophages, promoted the maturation of DCs, and stimulated the expression of cytokines. In addition, it demonstrated an excellent anti-tumor efficacy in vivo by eliciting a strong CD8+ T immune response. Taken together, our observations revealed a powerful immune stimulating nanomaterial that is a promising compound for cancer immunotherapy.

Antioxidant enzymes, hematology and histology of spleen in Nile tilapia fed supplemented diet with natural extracts challenged with Aeromonas hydrophila

This study investigated the effects of dietary supplementation with the extrats of propolis and Aloe barbadensis (aloe) on the antioxydant enzime activity, hematology and histology of the spleen of Nile tilapia challenged with Aeromonas hydrophila. Seventy two juvenile Nile tilapia were divided in four treatments and three replicates and fed extract mixture for 15 days: fish fed supplemented diet with 1% of the mixture of extracts of propolis and aloe (1:1) injected with phosphate-buffered saline (PBS); fish fed suplemented diet with 1% of the mixture of extracts of propolis and aloe (1:1) injected with the A. hydrophila, fish fed supplemented diet with the mixture of propolis extracts and aloe, injected with PBS and injected with A. hydrophila. The influence of the supplementation of propolis and Aloe extracts on the immunomodulation in tilapias was observed by the evaluation of the survival of the animals after challenge with A. hydrophila. Non-supplemented fish had a 44.5% survival rate and those supplemented with 1% of the mixture of extracts showed 55.6% survival 7 days after challenge. The supplemented animals also showed a significant increase in the number of lymphocytes in the evaluation of the blood parameters and, consequently, in the histopathological evaluation, presented greater presence of centers of melanomacrophages. In addition, the activity of the antioxidant enzymes glutathione reductase (GR) in the spleen presented a significant difference in fish supplemented with 1% of the extracts mixture, being superior in the animals injected with PBS when compared to those challenged with A. hydrophila.

Honey: an immunomodulator in wound healing

Honey is a popular natural product that is used in the treatment of burns and a broad spectrum of injuries, in particular chronic wounds. The antibacterial potential of honey has been considered the exclusive criterion for its wound healing properties. The antibacterial activity of honey has recently been fully characterized in medical-grade honeys. Recently, the multifunctional immunomodulatory properties of honey have attracted much attention. The aim of this review is to provide closer insight into the potential immunomodulatory effects of honey in wound healing. Honey and its components are able to either stimulate or inhibit the release of certain cytokines (tumor necrosis factor-α, interleukin-1β, interleukin-6) from human monocytes and macrophages, depending on wound condition. Similarly, honey seems to either reduce or activate the production of reactive oxygen species from neutrophils, also depending on the wound microenvironment. The honey-induced activation of both types of immune cells could promote debridement of a wound and speed up the repair process. Similarly, human keratinocytes, fibroblasts, and endothelial cell responses (e.g., cell migration and proliferation, collagen matrix production, chemotaxis) are positively affected in the presence of honey; thus, honey may accelerate reepithelization and wound closure. The immunomodulatory activity of honey is highly complex because of the involvement of multiple quantitatively variable compounds among honeys of different origins. The identification of these individual compounds and their contributions to wound healing is crucial for a better understanding of the mechanisms behind honey-mediated healing of chronic wounds.

Scientific Validation of Gentiana kurroo Royle for Anti-Inflammatory and Immunomodulatory Potential

Gentiana kurroo Royle is a critically endangered medicinal plant species endemic to the northwestern Himalayas. This plant was studied for the immunomodulatory and anti-inflammatory potential. Carrageenan paw edema model was used to study the potential of the drug in inflammation in Wistar rats. SRBC specific haemagglutination titre and DTH assays were carried out in Balb/C mice for observing the effect of test drugs on immune system. The plant extracts were found to be active against inflammation. The methanolic fraction was observed to be the most effective in inhibition of paw edema with the inhibitory potential of 47.62%. In immunomodulation studies the plant extracts showed the immunosuppressant activity. Methanolic fraction was observed to have maximum potential for the suppression of both humoral (57.57% and 54.05%) and cell mediated immunity (65.27% and 75%). From these studies, it can be concluded that the extracts of plant are having anti-inflammatory and immunosuppressant activity. Since in chronic inflammation like arthritis there is the involvement of immune system, this plant may serve as an alternative for the treatment of autoimmune diseases like arthritis.

Evaluation of Artemisia amygdalina D. for Anti-Inflammatory and Immunomodulatory Potential

Artemisia amygdalina D. is a critically endangered endemic medicinal plant of Kashmir Himalayas. In the current study anti-inflammatory and immunomodulatory activity of the plant was carried out. Carrageenan paw edema model was used to study the potential of the drug in inflammation in Wistar rats. SRBC-specific haemagglutination titre and DTH assays were carried out in Balb/C mice for observing the effect of test drugs on immune system. The plant extracts used as test drugs showed to have anti-inflammatory potential. The methanolic fraction was observed to have the maximum effect on the inhibition of paw edema formation with the inhibitory potential of 42.26%, while in the immunomodulation studies the test drugs were found to have the immunosuppressant activity with methanolic fraction again showing the maximum potential for the suppression of both humoral (55.89% and 47.91%) and cell-mediated immunity (62.27% and 57.21%). The plant in total seems to have the anti-inflammatory potential. The suppression of immune system suggests some mechanistic way by which the inhibition of inflammation takes place. Since, in chronic inflammation like arthritis, there is the involvement of immune system, the plant in that way may serve as an alternative for the treatment of such autoimmune diseases.

Anti-inflammatory and immunomodulatory effects of Baccharis trimera aqueous extract on induced pleurisy in rats and lymphoproliferation in vitro

Baccharis trimera is a widespread South American plant known as "carqueja". Medicinal teas prepared from the aerial parts of this plant are used in folk medicine in cases of liver diseases and inflammatory processes. We evaluated the effects of aqueous extract of B. trimera in the experimental inflammatory model of carrageenan-induced pleurisy in rat. The injection of carrageenan into the pleural cavity induces an influx of cells and fluid accumulation with a large number of polymorphonuclear leukocytes and increase of protein levels. The inflammation parameters were attenuated when B. trimera (400 and 800 mg/kg, i.p.) was administrated 30 min before the carrageenan. The immunomodulatory effects were evaluated in vitro on human peripheral blood mononuclear cells. The extract in concentration of 25, 50 and 100 mg/mL presented inhibited the T-lymphocytes proliferation stimulated by phytohemagglutinin, but these extract concentrations also presented cytotoxic effect. These results showed that the aqueous extract of B. trimera has anti-inflammatory effect.

Evaluation of immunomodulatory effect of three herbal plants growing in Egypt

A group of medicinal plant including Silene (Silene nocturna), Black seed (Nigella sativa) and Chamomile (Matricaria chamomilla) growing in Egypt were examined for their immunomodulatory effect in Balb/c mice. Treatment (intraperitoneal injection) with five doses of methanolic extract for each plant was found to enhance the total white blood cells count (up to 1.2 × 10(4) cells/mm(3)). Bone marrow cellularity also increased significantly (P < 0.01) after the administration of the extract of each of three test plants. Furthermore, spleen weight of the treated groups was significantly increased (P < 0.01). Two groups of mice were immunosuppressed with cyclophosphamide, the one which pretreated with the plants extracts significantly (P < 0.01) restored their resistance against lethal infection with the predominately granulocyte-dependant Candida albicans. These results confirm the immunomodulatory activity of Silene, Black seed, and Chamomile extracts and may have therapeutical implications in prophylactic treatment of opportunistic infections and as supportive treatment in oncogenic cases.

A review of immunomodulators with reference to Canova

Immunomodulators are substances which modify the immunity of an individual to favour a particular immunological response. The immune response and the function of the immune response regulation process are described, with special reference to cancer and autoimmune disease. Homeopathy and its role in immune regulation are discussed with special reference to Canova. Canova is a homeopathic product produced, according to the Hahnemannian homeopathic method, in Brazil. Its role in cancer, bone marrow and haematopoiesis as well as macrophage and monocyte activation is reviewed. Canova seems to stabilize platelet morphology in human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS). The data suggest that the future of immunomodulators and homeopathic products which appear to have an effect on the immune response requires a better understanding of the relative need for immune activation versus immune modulation. Homeopathic products specifically need more attention.

Targeting tumors with peptides from natural sources

Peptide-based therapies offer the potential for non-genotoxic, genotype-specific alternatives, or adjuvants, to the current range of traditional cancer treatments. Such a patient-tailored cancer-cell-directed therapeutic approach should have fewer side effects and could well be more effective than the current drug- or combination-based regimens. Here, we review the potential of novel natural anticancer peptides such as necrotic peptides, apoptotic peptides, function-blocking peptides, antiangiogenic peptides and immunostimulatory peptides in the context of their ability to induce tumor regression. We focus on the therapeutic prospects of anticancer peptides and their possible application in tumor therapy.

The immunostimulatory effect of the recombinant apalbumin 1–major honeybee royal jelly protein–on TNFα release

Apalbumin1 (Apa1) is the major royal jelly (RJ) and honey glycoprotein having various biological properties. We have previously demonstrated that Apa1 is a regular component of honey and honeybee pollen and stimulates macrophages to release tumor necrosis factor alpha (TNFalpha). The recombinant Apa1 (rApa1) and its four recombinant protein fragments derived on the basis of partial tryptic products of Apa1 were prepared by heterologous expression in Escherichia coli BL21-CodonPlus(DE3)-RIL. L-arginine at 50 mM concentration was used for improving the recombinant protein solubility. We report that the proteinous moiety of glycoprotein is responsible for stimulation of TNFalpha production by murine peritoneal macrophages. Moreover, we have shown that immunostimulatory effect is significantly increased after partial tryptic digestion of Apa1. It has been determined that recombinant N-terminal fragment of Apa1 is the most active elicitor of TNFalpha release in comparison to other three protein fragments of Apa1, as well as to the native Apa1 and rApa1. Furthermore, it was found that native honey was able to stimulate TNFalpha secretion from murine macrophages, whereas the deproteinized honey had no effect on the release of TNFalpha. This result suggests that immunostimulatory effect of honey is based on its RJ-protein content, primarily on its dominant protein Apa1.

Immunostimulatory Role of Tryptic Digest ofAbrusAgglutinin

Many bioactive peptides are in therapeutic use as immunomodulators at present. The origin of these bioactive peptides is diverse. Such bioactive peptides are reported to be present in enzymatic digest of food and milk proteins. In our previous work we have reported that Abrus agglutinin retains its bioactivity even after heat denaturation but loses its haemagglutination properties. This leads to the supposition that immunostimulatory regions in the protein might be responsible for its in vivo and in vitro stimulatory properties. Thus the bioactivity of tryptic digest of Abrus agglutinin (TDA) was checked in vitro to ascertain the presence of some bioactive region in the protein, which will lead to the discovery of certain immunostimulatory peptides which might be of use in nonspecific immunotherapy. In this study it is observed that TDA stimulates macrophage increasing the phagocytic and bactericidal activity as well as hydrogen peroxide production. TDA also proliferates splenocytes leading to Th1 response and NK cell activation.