Bee venom modulates murine Th1/Th2 lineage development

Melittin-incorporated nanomedicines for enhanced cancer immunotherapy

Immunotherapy is a rapidly developing and effective strategy for cancer therapy. Among various immunotherapy approaches, peptides have garnered significant attention due to their potent immunomodulatory effects. In particular, melittin emerged as a promising candidate to enhance cancer immunotherapy by inducing immunogenic cell death, promoting the maturation of antigen-presenting cells, activating T cells, enhancing the infiltration and cytotoxicity of effector lymphocytes, and modulating macrophage phenotypes for relieving immunosuppression. However, the clinical application of melittin is limited by poor targeting and systemic toxicity. To overcome these challenges, melittin has been incorporated into biomaterials and related nanotechnologies, resulting in extended circulation time in vivo, improved targeting, reduced adverse effects, and enhanced anti-cancer immunological action. This review provides an in-depth analysis of the immunomodulatory effects of melittin-incorporated nanomedicines and examines their development and challenges for clinical cancer immunotherapy.

Bee Venom and Its Two Main Components-Melittin and Phospholipase A2-As Promising Antiviral Drug Candidates

Viruses are known to infect most types of organisms. In humans, they can cause several diseases that range from mild to severe. Although many antiviral therapies have been developed, viral infections continue to be a leading cause of morbidity and mortality worldwide. Therefore, the discovery of new and effective antiviral agents is desperately needed. Animal venoms are a rich source of bioactive molecules found in natural goods that have been used since ancient times in alternative medicine to treat a variety of human diseases. Recently, and with the onset of the COVID-19 pandemic, scientists have regained their interest in the possible use of natural products, such as bee venom (BV), as a potential antiviral agent to treat viral infections. BV is known to exert many therapeutic activities such as anti-proliferative, anti-bacterial, and anti-inflammatory effects. However, there is limited discussion of the antiviral activity of BV in the literature. Therefore, this review aims to highlight the antiviral properties of BV and its two primary constituents, melittin (MEL) and phospholipase A2 (PLA2), against a variety of enveloped and non-enveloped viruses. Finally, the innovative strategies used to reduce the toxicity of BV and its two compounds for the development of new antiviral treatments are also considered.

Bio-nano scale modifications of melittin for improving therapeutic efficacy

INTRODUCTION

Melittin (MLT), a natural membrane-active component, is the most prominent cytolytic peptide from bee venom. Remarkable biological properties of MLT, including anti-inflammatory, antimicrobial, anticancer, anti-protozoan, and antiarthritic activities, make it an up-and-coming therapeutic candidate for a wide variety of human diseases. Therapeutic applications of MLT may be hindered due to low stability, high toxicity, and weak tissue penetration. Different bio-nano scale modifications hold promise for improving its functionality and therapeutic efficacy.

AREAS COVERED

In the current review, we aimed to provide a comprehensive insight into strategies used for MLT conjugations and modifications, cellular delivery of modified forms, and their clinical perspectives by reviewing the published literature on PubMed, Scopus, and Google Scholar databases. We also emphasized the MLT structure modifications, mechanism of action, and cellular toxicity.

EXPERT OPINION

Developing new analogs and conjugates of MLT as a natural drug with improved functions and fewer side effects is crucial for the clinical translation of this approach worldwide, especially where the chemicals and synthetic drugs are more expensive or unavailable in the healthcare system. MLT-nanoconjugation may be one of the best-optimized strategies for improving peptide delivery, increasing its therapeutic efficacy, and providing minimal nonspecific cellular lytic activity. [Figure: see text].

Immunological Responses to Envenomation

Venoms are complex mixtures of toxic compounds delivered by bite or sting. In humans, the consequences of envenomation range from self-limiting to lethal. Critical host defence against envenomation comprises innate and adaptive immune strategies targeted towards venom detection, neutralisation, detoxification, and symptom resolution. In some instances, venoms mediate immune dysregulation that contributes to symptom severity. This review details the involvement of immune cell subtypes and mediators, particularly of the dermis, in host resistance and venom-induced immunopathology. We further discuss established venom-associated immunopathology, including allergy and systemic inflammation, and investigate Irukandji syndrome as a potential systemic inflammatory response. Finally, this review characterises venom-derived compounds as a source of immune modulating drugs for treatment of disease.

Delivery Strategies for Melittin-Based Cancer Therapy

Melittin (MLT) has been studied preclinically as an anticancer agent based on its broad lytic effects in multiple tumor types. However, unsatisfactory tissue distribution, hemolysis, rapid metabolism, and limited specificity are critical obstacles that limit the translation of MLT. Emerging drug delivery strategies hold promise for targeting, controlled drug release, reduced side effects, and ultimately improved treatment efficiency. In this review, we discuss recent advances in the use of diverse carriers to deliver MLT, with an emphasis on the design and mechanisms of action. We further outline the opportunities for MLT-based cancer immunotherapy.

Melittin-lipid nanoparticles target to lymph nodes and elicit a systemic anti-tumor immune response

Targeted delivery of a nanovaccine loaded with a tumor antigen and adjuvant to the lymph nodes (LNs) is an attractive approach for improving cancer immunotherapy outcomes. However, the application of this technique is restricted by the paucity of suitable tumor-associated antigens (TAAs) and the sophisticated technology required to identify tumor neoantigens. Here, we demonstrate that a self-assembling melittin-lipid nanoparticle (α-melittin-NP) that is not loaded with extra tumor antigens promotes whole tumor antigen release in situ and results in the activation of antigen-presenting cells (APCs) in LNs. Compared with free melittin, α-melittin-NPs markedly enhance LN accumulation and activation of APCs, leading to a 3.6-fold increase in antigen-specific CD8⁺ T cell responses. Furthermore, in a bilateral flank B16F10 tumor model, primary and distant tumor growth are significantly inhibited by α-melittin-NPs, with an inhibition rate of 95% and 92%, respectively. Thus, α-melittin-NPs induce a systemic anti-tumor response serving as an effective LN-targeted whole-cell nanovaccine.

Natural Vaccine Adjuvants and Immunopotentiators Derived From Plants, Fungi, Marine Organisms, and Insects

Immunopotentiators derived from different natural sources are under investigation with varying success. This chapter gives an overview of developments from plants, fungi, marine organisms, and insects. Plant-derived immune stimulators consist of a diverse range of small molecules or large polysaccharides. Notable examples that have been assessed in both preclinical and clinical trials include saponins, tomatine, and inulin. Similarly, fungi produce a range of potential candidate molecules, with β-glucans showing the most promise. Other complex molecules that have established adjuvant activity include α-galactosylceramide (originally obtained from a marine sponge), chitosan (commonly produced from chitin from shrimps), and peptides (found in bee venom). Some organisms, for example, endophytic fungi and bees, produce immunostimulants using compounds obtained from plants. The main challenges facing this type of research and tools being developed to overcome them are examined.

Therapeutic Effects of Bee Venom on Immunological and Neurological Diseases

Bee Venom (BV) has long been used in Korea to relieve pain symptoms and to treat inflammatory diseases, such as rheumatoid arthritis. The underlying mechanisms of the anti-inflammatory and analgesic actions of BV have been proved to some extent. Additionally, recent clinical and experimental studies have demonstrated that BV and BV-derived active components are applicable to a wide range of immunological and neurodegenerative diseases, including autoimmune diseases and Parkinson's disease. These effects of BV are known to be mediated by modulating immune cells in the periphery, and glial cells and neurons in the central nervous system. This review will introduce the scientific evidence of the therapeutic effects of BV and its components on several immunological and neurological diseases, and describe their detailed mechanisms involved in regulating various immune responses and pathological changes in glia and neurons.

Honeybee (Apis mellifera) Venom Reinforces Viral Clearance during the Early Stage of Infection with Porcine Reproductive and Respiratory Syndrome Virus through the Up-Regulation of Th1-Specific Immune Responses

Porcine reproductive and respiratory syndrome (PRRS) is a chronic and immunosuppressive viral disease that is responsible for substantial economic losses for the swine industry. Honeybee venom (HBV) is known to possess several beneficial biological properties, particularly, immunomodulatory effects. Therefore, this study aimed at evaluating the effects of HBV on the immune response and viral clearance during the early stage of infection with porcine reproductive and respiratory syndrome virus (PRRSV) in pigs. HBV was administered via three routes of nasal, neck, and rectal and then the pigs were inoculated with PRRSV intranasally. The CD4⁺/CD8⁺ cell ratio and levels of interferon (IFN)-γ and interleukin (IL)-12 were significantly increased in the HBV-administered healthy pigs via nasal and rectal administration. In experimentally PRRSV-challenged pigs with virus, the viral genome load in the serum, lung, bronchial lymph nodes and tonsil was significantly decreased, as was the severity of interstitial pneumonia, in the nasal and rectal administration group. Furthermore, the levels of Th1 cytokines (IFN-γ and IL-12) were significantly increased, along with up-regulation of pro-inflammatory cytokines (TNF-α and IL-1β) with HBV administration. Thus, HBV administration—especially via the nasal or rectal route—could be a suitable strategy for immune enhancement and prevention of PRRSV infection in pigs.

Immunoprophylactic effects of administering honeybee (Apis melifera) venom spray against Salmonella gallinarum in broiler chicks

Antibiotics continue to be used as growth promoters in the poultry industry. Honeybee (Apis melifera) venom (HBV) possesses a number of beneficial biological activities, particularly for regulating the immune system. The aim of the present study was to evaluate the immunoprophylactic effects of HBV against Salmonella Gallinarum in broiler chicks as an initial step towards developing eco-friendly alternatives to reduce antibiotic use. HBV was administered using a spray technique. HBV improved body weight gain, particularly in the presence of infection. Moreover, HBV enhanced antibody production activity against formalin-killed S. Gallinarum. The CD4⁺:CD8⁺ T lymphocyte ratio, relative mRNA expression levels of interleukin-18 and interferon-γ, and serum lysozyme activity also increased following HBV administration before the infection period as well as during infection. HBV reinforced bacterial clearance and increased survivability against S. Gallinarum. Corresponding pathological analyses demonstrated that the HBV-sprayed group displayed mild and less severe abnormal changes compared with those in the control group. It was presumed that the prophylactic effects of HBV against S. Gallinarum were associated with its non-specific immune response stimulating activity. Thus, HBV may provide an alternative to reduce antibiotic use in the poultry industry.

Bee venom ameliorates ovalbumin induced allergic asthma via modulating CD4+CD25+ regulatory T cells in mice

Asthma is a potentially life-threatening inflammatory disease of the lung characterized by the presence of large numbers of CD4+ T cells. These cells produce the Th2 and Th17 cytokines that are thought to orchestrate the inflammation associated with asthma. Bee venom (BV) has traditionally been used to relieve pain and to treat chronic inflammatory diseases. Recent reports have suggested that BV might be an effective treatment for allergic diseases. However, there are still unanswered questions related to the efficacy of BV therapy in treating asthma and its therapeutic mechanism. In this study, we evaluated whether BV could inhibit asthma and whether BV inhibition of asthma could be correlated with regulatory T cells (Treg) activity. We found that BV treatment increased Treg populations and suppressed the production of Th1, Th2 and Th17-related cytokines in an in vitro culture system, including IL2, IL4, and IL17. Interestingly, production of IL10, an anti-inflammatory cytokine secreted by Tregs, was significantly augmented by BV treatment. We next evaluated the effects of BV treatment on allergic asthma in an ovalbumin (OVA)-induced mouse model of allergic asthma. Cellular profiling of the bronchoalveolar lavage (BAL) and histopathologic analysis demonstrated that peribronchial and perivascular inflammatory cell infiltrates were significantly lowered following BV treatment. BV also ameliorated airway hyperresponsiveness, a hallmark symptom of asthma. In addition, IL4 and IL13 levels in the BAL fluid were decreased in the BV treated group. Surprisingly, the beneficial effects of BV treatment on asthma were eradicated following Treg depletion by anti-CD25 antibody injection, suggesting that the major therapeutic targets of BV were Tregs. These results indicate that BV efficiently diminishes bronchial inflammation in an OVA-induced allergic asthma murine model, and that this effect might correlate with Tregs, which play an important role in maintaining immune homeostasis and suppressing the function of other T cells to limit the immune response. These results also suggest that BV has potential therapeutic value for controlling allergic asthma responses.

Bee venom in cancer therapy

Bee venom (BV) (api-toxin) has been widely used in the treatment of some immune-related diseases, as well as in recent times in treatment of tumors. Several cancer cells, including renal, lung, liver, prostate, bladder, and mammary cancer cells as well as leukemia cells, can be targets of bee venom peptides such as melittin and phospholipase A2. The cell cytotoxic effects through the activation of PLA2 by melittin have been suggested to be the critical mechanism for the anti-cancer activity of BV. The induction of apoptotic cell death through several cancer cell death mechanisms, including the activation of caspase and matrix metalloproteinases, is important for the melittin-induced anti-cancer effects. The conjugation of cell lytic peptide (melittin) with hormone receptors and gene therapy carrying melittin can be useful as a novel targeted therapy for some types of cancer, such as prostate and breast cancer. This review summarizes the current knowledge regarding potential of bee venom and its compounds such as melittin to induce cytotoxic, antitumor, immunomodulatory, and apoptotic effects in different tumor cells in vivo or in vitro. The recent applications of melittin in various cancers and a molecular explanation for the antiproliferative properties of bee venom are discussed.

Bee venom protects hepatocytes from tumor necrosis factor-alpha and actinomycin D

Honeybee (Apis mellifera) venom (BV) has a broad array of therapeutic applications in traditional medicine to treat variety of diseases. It is also known that BV possesses anti-inflammatory and anticancer effect and that it can inhibit proliferation and induces apoptosis in cancer cells, but there is no evidence of information regarding anti-apoptosis of BV on hepatocytes. In the present study, we investigated the anti-apoptotic effect of BV on tumor necrosis factor (TNF)-alpha with actinomycin (Act) D induces apoptosis in hepatocytes. TNF-alpha/Act D-treated hepatocytes were exposed to different low concentration (1, 10 and 100 ng/mL) of BV. Our results showed statistically significant inhibition in DNA damage caused by BV treatment compared to corresponding TNF-alpha/Act D-treated hepatocytes. BV suppressed TNF-alpha/Act Dtreated activation of bcl-2 family and caspase family, which resulted in inhibition of cytochrome c release and PARP cleavage. These results demonstrate that low concentration BV possess a potent suppressive effect on anti-apoptotic responses of TNF-alpha/Act D-treated hepatocytes and suggest that these compounds may contribute substantial therapeutic potential for the treatment of liver diseases.

Effects of bee venom on cholecystokinin octapeptide-induced acute pancreatitis in rats

OBJECTIVES

Bee venom (BV) has frequently been used as a remedy for inflammatory diseases. The aim of this study was to investigate the effect of BV on cholecystokinin octapeptide (CCK-8)-induced acute pancreatitis (AP) in rats.

METHODS

The BV pretreatment group: 0.25 mg/kg BV was administered subcutaneously, followed by 75 mug/kg CCK-8 subcutaneously 3 times after 1, 3, and 5 hours. This whole procedure was repeated for 5 days.

CONTROL GROUP

CCK-8 subcutaneously 3 times after 1, 3, and 5 hours for 5 days. The BV posttreatment group: CCK-8 subcutaneously 3 times at an interval of 2 hours for 3 days, and then 0.25 mg/kg of BV was administered subcutaneously.

CONTROL GROUP

CCK-8 subcutaneously 3 times at an interval of 2 hours for 3 days.

RESULTS

The BV pretreatment and posttreatment ameliorated many of the examined laboratory parameters (the pancreatic weight [PW]/body weight [BW] ratio, the serum amylase and lipase activity) and reduced histological damages in pancreas. Furthermore, BV pretreatment reduced the production of tumor necrosis factor-alpha, interleukin 1, and interleukin 6 and also decreased pancreatic nuclearfactor-kappaB binding activity compared with saline-treated group in the AP model. The BV also increased heat shock protein 60 (HSP60) and heat shock protein 72 (HSP72) compared with the saline-treated group in the AP model.

CONCLUSIONS

These findings suggest that the anti-inflammatory effect of BV in CCK-8-induced AP seems to be mediated by inhibiting nuclear factor-kappaB binding activity, and that BV may have a protective effect against AP.

Melittin, a major bioactive component of bee venom toxin, inhibits PDGF receptor beta-tyrosine phosphorylation and downstream intracellular signal transduction in rat aortic vascular smooth muscle cells

Studies previously reported that melittin, a major bioactive component of bee venom, inhibits vascular smooth muscle cell (VSMC) proliferation through suppression of nuclear factor (NF)-kappaB and Akt activation and through enhancement of proapoptotic protein expression. In this study, the effects of melittin were investigated on the tyrosine phosphorylation of platelet-derived growth factor (PDGF) beta receptor (Rbeta) and its downstream intracellular signal transduction. When combined with PDGF-Rbeta inhibitor, melittin exhibited a synergic inhibitory effect on PDGF-BB-induced rat aortic VSMC proliferation. In addition, melittin inhibited PDGF-Rbeta phosphorylation in a concentration-dependent manner. Accordingly, the downstream signal transduction of PDGF-Rbeta, such as ERK1/2, Akt, and PLCgamma1 phosphorylation, was also inhibited by melittin in the same manner. These findings suggest that, in addition to suppressing NF-kappaB activation, the antiproliferative effect of melittin in VSMC may be mediated, at least in part, by the inhibition of PDGF-Rbeta tyrosine phosphorylation and its downstream intracellular signal transduction.

Melittin inhibits vascular smooth muscle cell proliferation through induction of apoptosis via suppression of nuclear factor-kappaB and Akt activation and enhancement of apoptotic protein expression

In the present study, we have investigated the bee venom (BV) and melittin (a major component of BV)-mediated antiproliferative effect and defined its mechanisms of action in cultured rat aortic vascular smooth muscle cell(s) (VSMC). BV and melittin ( approximately 0.4-0.8 microg/ml) effectively inhibited 5% fetal bovine serum-induced and 50 ng/ml platelet-derived growth factor BB (PDGF-BB)-induced VSMC proliferation. The regulation of apoptosis has attracted much attention as a possible means of eliminating excessively proliferating VSMC. In the present study, the treatment of BV and melittin strongly induced apoptosis of VSMC. To investigate the antiproliferative mechanism of BV and melittin, we examined the effect of melittin on nuclear factor kappaB (NF-kappaB) activation, the PDGF-BB-induced IkappaBalpha phosphorylation, and its degradation were potently inhibited by melittin and whether DNA binding activity and nuclear translocation of NF-kappaB p50 subunit in response to the action of PDGF-BB were potently attenuated by melittin. In further investigations, melittin markedly inhibited the PDGF-BB-induced phosphorylation of Akt and weakly inhibited phosphorylation of extracellular signal-regulated kinase 1/2, upstream signals of NF-kappaB. Treatment of melittin also potently induced proapoptotic protein p53, Bax, and caspase-3 expression but decreased antiapoptotic protein Bcl-2 expression. These results suggest the antiproliferative effects of BV and melittin in VSMC through induction of apoptosis via suppressions of NF-kappaB and Akt activation and enhancement of apoptotic signaling pathway.