Bee venom inhibits tumor angiogenesis and metastasis by inhibiting tyrosine phosphorylation of VEGFR-2 in LLC-tumor-bearing mice

Enhancing Selective Antimicrobial and Antibiofilm Activities of Melittin through 6-Aminohexanoic Acid Substitution

Leucine residues are commonly found in the hydrophobic face of antimicrobial peptides (AMPs) and are crucial for membrane permeabilization, leading to the cell death of invading pathogens. Melittin, which contains four leucine residues, demonstrates broad-spectrum antimicrobial properties but also significant cytotoxicity against mammalian cells. To enhance the cell selectivity of melittin, this study synthesized five analogs by replacing leucine with its structural isomer, 6-aminohexanoic acid. Among these analogs, Mel-LX3 exhibited potent antibacterial activity against both Gram-positive and Gram-negative bacteria. Importantly, Mel-LX3 displayed significantly reduced hemolytic and cytotoxic effects compared to melittin. Mechanistic studies, including membrane depolarization, SYTOX green uptake, FACScan analysis, and inner/outer membrane permeation assays, demonstrated that Mel-LX3 effectively permeabilized bacterial membranes similar to melittin. Notably, Mel-LX3 showed robust antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant Pseudomonas aeruginosa (MDRPA). Furthermore, Mel-LX3 effectively inhibited biofilm formation and eradicated existing biofilms of MDRPA. With its improved selective antimicrobial and antibiofilm activities, Mel-LX3 emerges as a promising candidate for the development of novel antimicrobial agents. We propose that the substitution of leucine with 6-aminohexanoic acid in AMPs represents a significant strategy for combating resistant bacteria.

Impact of apitherapy on canine, equine, and chicken lymphocytes, in vitro

Apitherapy is a form of alternative medicine that utilizes products from the western honeybee (Apis mellifera), including honey, propolis, and honeybee venom, to improve the health status of human patients by altering host immunity. An added benefit of these products is that they are nutraceuticals and relatively inexpensive to aquire. Currently, little is known about the use of honeybee products in veterinary species, as well as their impact on host immunity. In the present in vitro study, honey, propolis, and honeybee venom were co-cultured with enriched canine, equine, and chicken peripheral blood lymphocytes (PBLs) with cell proliferation, cell viability/apoptosis, and cellular morphology evaluated. Concanavalin A (Con A) and dexamethasone were used as stimulatory and suppressive controls, respectively. Honeybee products' effects on the three veterinary species varied by product and the species. Honey stimulated the PBLs proliferation in all three species but also displayed some increased cytotoxicity. Propolis stimulated proliferation in canine and equine PBLs, however, it suppressed proliferation in the chicken PBLs. Honeybee venom was the strongest PBL stimulant for all three species and in the equine, surpassed the stimulant response of Con A and yet, enhanced PBL cell viability post culture. In summary, the results of this preliminary in vitro study show that these three honeybee products do impact lymphocyte proliferation and viability in dogs, horses, and chickens, and that more research both in vitro and in vivo will be necessary to draw conclusions regarding their future use as immune stimulants or inhibitors.

Synergistic effects of bee venom, hesperidin, and piperine with tamoxifen on apoptotic and angiogenesis biomarker molecules against xerographic MCF-7 injected rats

Breast cancer ranks as the second leading most significant of mortality for women. Studies have demonstrated the potential benefits of natural compounds in cancer treatment and prevention, either in isolation or in conjunction with chemotherapy. In order to improve Tamoxifen's therapeutic efficacy in in-vivo studies, our research sought to determine the effects of hesperidin, piperine, and bee venom as natural compounds, as well as their combination effect with or without Tamoxifen. First, 132 female albino rats were equally divided into six groups and five subgroups, and breast cancer was induced in the selected groups by xenografting of MCF7 cells. Second, the effect of single and best ratio combinations treatment from previous in vitro studies were selected. Next, tumorous mammary glands were collected for apoptotic and antiapoptotic biomarkers and cell cycle analysis. Single or combined natural products with or without Tamoxifen revealed a significant up-regulation in apoptotic genes Bax and Casp3 and a downregulation of antiapoptotic and angiogenesis genes Bcl-2 and VEGF genes. We found that cell cycle arrest in the G0/G1 phase was exclusively caused by Tamoxifen and/ or hesperidin. However, the cell cycle arrest in the G2/M phase is a result of the combination of piperine and bee venom, with or without Tamoxifen by using the flow cytometric technique. Our research concludes that bee venom, hesperidin, and piperine can synergistically enhance to increase Tamoxifen's efficiency in the management of breast cancer.

Tea polyphenols, astaxanthin, and melittin can significantly enhance the immune response of juvenile spotted knifejaw (Oplegnathus punctatus)

The frequent occurrence of diseases seriously hampers the sustainable development of the spotted knifejaw (Oplegnathus punctatus) breeding industry. Our previous genome-wide scan and cross-species comparative genomic analysis revealed that the immune gene family (Toll-like receptors, TLR) members of O. punctatus underwent a significant contraction event (tlr1, tlr2, tlr14, tlr5, and tlr23). To address immune genetic contraction may result in reduced immunity, we investigated whether adding different doses (0, 200, 400, 600, and 800 mg/kg) of immune enhancers (tea polyphenols, astaxanthin, and melittin) to the bait after 30 days of continuous feeding could stimulate the immune response of O. punctatus. We found that the expression of tlr1, tlr14, tlr23 genes in immune organs (spleen and head kidney) was stimulated when tea polyphenols were added at 600 mg/kg. The tlr2 (400 mg/kg), tlr14 (200 mg/kg), tlr5 (200 mg/kg), and tlr23 (200 mg/kg) genes expression of intestine were elevated in the tea polyphenol group. When the addition of astaxanthin is 600 mg/kg, it can effectively stimulate the expression of tlr14 gene in immune organs (liver, spleen and head kidney). In the astaxanthin group, the expression of the genes tlr1 (400 mg/kg), tlr14 (600 mg/kg), tlr5 (400 mg/kg) and tlr23 (400 mg/kg) reached their highest expression in the intestine. Besides, the addition of 400 mg/kg of melittin can effectively induce the expression of tlr genes in the liver, spleen and head kidney, except the tlr5 gene. The tlr-related genes expression in the intestine was not significantly elevated in the melittin group. We hypothesize that the immune enhancers could enhance the immunity of O. punctatus by increasing the expression of tlr genes, and thereby leading to increased resistance to diseases. Meanwhile, our findings further demonstrated that significant increases in weight gain rate (WGR), visceral index (VSI), and feed conversion rate (FCR) were observed at 400 mg/kg, 200 mg/kg and 200 mg/kg of tea polyphenols, astaxanthin and melittin in the diet, respectively. Overall, our study provided valuable insights for future immunity enhancement and viral infection prevention in O. punctatus, as well as offered guidance for the healthy development of the O. punctatus breeding industry.

Therapeutic Use of Bee Venom and Potential Applications in Veterinary Medicine

Apitherapy is a branch of alternative medicine that consists of the treatment of diseases through products collected, processed, and secreted by bees, specifically pollen, propolis, honey, royal jelly, and bee venom. In traditional medicine, the virtues of honey and propolis have been well-known for centuries. The same, however, cannot be said for venom. The use of bee venom is particularly relevant for many therapeutic aspects. In recent decades, scientific studies have confirmed and enabled us to understand its properties. Bee venom has anti-inflammatory, antioxidant, central nervous system inhibiting, radioprotective, antibacterial, antiviral, and antifungal properties, among others. Numerous studies have often been summarised in reviews of the scientific literature that have focused on the results obtained with mouse models and their subsequent transposition to the human patient. In contrast, few reviews of scientific work on the use of bee venom in veterinary medicine exist. This review aims to take stock of the research achievements in this particular discipline, with a view to a recapitulation and stabilisation in the different research fields.

Pharmacological properties and therapeutic potential of honey bee venom

Honey bee venom (BV) is a valuable product, and has a wide range of biological effects, and its use is rapidly increasing in apitherapy. Therefore, the current study, we reviewed the existing knowledge about BV composition and its numerous pharmacological properties for future research and use. Honey bee venom or apitoxin is produced in the venom gland in the honey bee abdomen. Adult bees use it as a primary colony defense mechanism. It is composed of many biologically active substances including peptides, enzymes, amines, amino acids, phospholipids, minerals, carbohydrates as well as some volatile components. Melittin and phospholipase A₂ are the most important components of BV, having anti-cancer, antimicrobial, anti-inflammatory, anti-arthritis, anti-nociceptive and other curative potentials. Therefore, in medicine, BV has been used for centuries against different diseases like arthritis, rheumatism, back pain, and various inflammatory infections. Nowadays, BV or its components separately, are used for the treatment of various diseases in different countries as a natural medicine with limited side effects. Consequently, scientists as well as several pharmaceutical companies are trying to get a new understanding about BV, its substances and its activity for more effective use of this natural remedy in modern medicine.

Evodiamine suppresses the progression of non-small cell lung carcinoma via endoplasmic reticulum stress-mediated apoptosis pathway in vivo and in vitro

BACKGROUND

Evodiamine (EVO) is one of the major components isolated from Evodia rutaecarpa (Juss.). Recent studies have shown that EVO has an anti-cancer effect. However, the pharmacological mechanism by which EVO impacts cancer is still poorly understood.

OBJECTIVES

This study focused on asking the anti-cancer effect of EVO in human non-small cell lung carcinoma (NSCLC), and in particular to investigate whether EVO acts via modulating the endoplasmic reticulum stress (ERS)-mediated apoptosis pathway.

MATERIALS AND METHODS

A Lewis lung carcinoma (LLC) tumor-bearing mouse model was treated with low-dose EVO (5 mg/kg) and high-dose EVO (10 mg/kg) intraperitoneally for 14 d. The effects of EVO on tumor growth, apoptosis, and ERS were assessed. In addition, NSCLC A549 and LLC cells were treated with EVO in vitro. The effects of EVO on cell proliferation, apoptosis, and ERS were investigated. Finally, 4-phenylbutyric acid (4-PBA), an ERS inhibitor, was used to validate whether EVO induced apoptosis of NSCLC cells by modulating ERS.

RESULTS

EVO treatment significantly inhibited tumor growth in LLC tumor-bearing mice. H&E staining indicated that EVO treatment reduced the number of tumor cells and the nucleo-plasmic ratio. Immunostaining showed that EVO treatment significantly decreased the expression of Ki-67. TUNEL staining revealed that EVO induced apoptosis in the tumor. Likewise, EVO treatment up-regulated the expression of apoptosis-related genes and proteins and increased activation of the ERS pathway in the tumor. Additionally, EVO inhibited cell proliferation and increased cell apoptotic rates in A549 and LLC cells. EVO also increased the expression levels of genes and proteins associated with ERS-mediated apoptosis pathway in vitro. The effects of EVO on apoptosis were abolished by 4-PBA treatment.

CONCLUSIONS

Our study demonstrated that EVO suppresses the progression of NSCLC by modulating the ERS-mediated apoptosis pathway.

Bee venom-loaded EGFR-targeting peptide-coupled chitosan nanoparticles for effective therapy of hepatocellular carcinoma by inhibiting EGFR-mediated MEK/ERK pathway

Hepatocellular carcinoma (HCC) is one of the world's most risky diseases due to the lack of clear and cost-effective therapeutic targets. Currently, the toxicity of conventional chemotherapeutic medications and the development of multidrug resistance is driving research into targeted therapies. The nano-biomedical field's potential for developing an effective therapeutic nano-sized drug delivery system is viewed as a significant pharmaceutical trend for the encapsulation and release of numerous anticancer therapies. In this regard, current research is centered on the creation of biodegradable chitosan nanoparticles (CSNPs) for the selective and sustained release of bee venom into liver cancer cells. Furthermore, surface modification with polyethylene glycol (PEG) and GE11 peptide-conjugated bee venom-CSNPs allows for the targeting of EGFR-overexpressed liver cancer cells. A series of in vitro and in vivo cellular analyses were used to investigate the antitumor effects and mechanisms of targeted bee venom-CSNPs. Targeted bee venom-CSNPs, in particular, were found to have higher cytotoxicity against HepG2 cells than SMMC-7721 cells, as well as stronger cellular uptake and a substantial reduction in cell migration, leading to improved cancer suppression. It also promotes cancer cell death in EGFR overexpressed HepG2 cells by boosting reactive oxygen species, activating mitochondria-dependent pathways, inhibiting EGFR-stimulated MEK/ERK pathway, and elevating p38-MAPK in comparison to native bee venom. In hepatocellular carcinoma (HCC)-induced mice, it has anti-cancer properties against tumor tissue. It also improved liver function and architecture without causing any noticeable toxic side effects, as well as inhibiting tumor growth by activating the apoptotic pathway. The design of this cancer-targeted nanoparticle establishes GE11-bee venom-CSNPs as a potential chemotherapeutic treatment for EGFR over-expressed malignancies. Finally, our work elucidates the molecular mechanism underlying the anticancer selectivity of targeted bee venom-CSNPs and outlines therapeutic strategies to target liver cancer.

Characteristics of Adverse Events in Bee Venom Therapy Reported in South Korea: A Survey Study

This study was aimed at investigating Korean patients’ experience with bee venom therapy (BVT) and providing evidence to enhance BVT safety. Thus, an anonymous online survey was conducted between August 22 and 28, 2018. Five hundred respondents who underwent pharmacopuncture (PA) within one year were surveyed (sample error: 95 ± 4.38%). Of these, 32 respondents were excluded and 468 were evaluated. Of the 468, 61 reported experiencing adverse events after PA. The adverse event rate was higher in the BV-PA(Bee venom-Pharmacopuncture) group than in the non-A group; however, intergroup differences were insignificant. There were no significant differences in mild symptom intensity between the BV-PA and non-BV-PA groups (p = 0.572). However, there was a significant intergroup difference in severe symptom intensity (p < 0.001). Additionally, the BV-PA and non-BV-PA groups did not significantly differ in their level of satisfaction either overall or in terms of effectiveness and safety (p = 0.414, p = 0.339, and p = 0.675, respectively). Furthermore, the BV-PA and non-BV-PA groups did not differ regarding intent to re-treat (p = 0.722). Severe adverse events such as anaphylactic shock were not reported; however, BVT practitioners should be cautious when applying it.

Role of Bee Venom and Melittin on Restraining Angiogenesis and Metastasis in γ-Irradiated Solid Ehrlich Carcinoma-Bearing Mice

Pathological angiogenesis and apoptosis evasion are common hallmarks of cancer. The present work was an endeavor to evaluate the influence of bee venom (BV) or its major constituent melittin (MEL) as antiapoptotic and angiogenic regulator modifier on the tumor growth and the cell sensitivity to ionizing radiation targeting the improvement of cancer therapeutic protocols. BV (0.56 mg/kg/day) and MEL (500 µg/kg body weight/day) were injected intraperitoneally to mice bearing 1 cm³ solid tumor of Ehrlich ascites carcinoma (EAC) for 21 consecutive days. Mice were whole-body exposed to 1 Gray (Gy) of γ-radiation (2 fractionated doses). Treatment with BV or MEL markedly suppresses the proliferation of tumor in EAC mice. The concentrations of m-RNA for angiogenic factors (TNF-α, VEGF) as well as MMPs 2 and 9 activities and NO concentration were significantly decreased, combined with improvements in apoptotic regulators (caspase-3 activity) and normal cells redox tone (catalase and free radicals content) compared with EAC mice. Moreover, the histopathological investigation confirms the improvement exerted by BV or MEL in the EAC mice group or EAC + R group. Exposure to γ-radiation sustained the modulatory effect of BV on tumor when compared with EAC + BV mice. Convincingly, the role of BV or MEL as a natural antiangiogenic in the biological sequelae after radiation exposure is verified. Hence, BV and its major constituent MEL might represent a potential therapeutic strategy for increasing the radiation response of solid tumors.

Apoptotic Effects of Melittin on 4T1 Breast Cancer Cell Line is associated with Up Regulation of Mfn1 and Drp1 mRNA Expression

BACKGROUND AND PURPOSE

Melittin, as the main ingredient of honeybee venom, that has shown anticancer properties. The present study aimed at investigating the cytotoxic impacts of melittin on 4T1 breast cancer cells.

METHODS

Hemolytic activity of different concentrations (0.125, 0.25, 0.5, 1, 2, 4, 8μg/ml) of melittin was assayed and then cytotoxicity of selected concentrations of melittin (2, 4, 8, 16, 32, and 64μg/ml), 2 and 4μg/ml of cisplatin and 0.513, 0.295 and 0.123μg/ml of doxorubicin was evaluated on 4T1 cells using MTT assay. We used Morphological evaluation and flow cytometric analysis was used. Real time PCR was also used to determine mRNA expression of Mfn1 and Drp1 genes.

RESULTS

All compounds showed anti-proliferative effects on the tumor cell line with different potencies. Melittin had higher cytotoxicity against 4T1 breast cancer cells (IC50= 32μg/ml-72h) and higher hemolytic activity (HD50= 1μg/ml), as compared to cisplatin and doxorubicin. Mellitin at 16 and 32μg/ml showed apoptotic effects on 4T1 cells according to the flow cytometric analysis. The Real time PCR analysis of Drp1 and Mfn1 expression in cells treated with 16μg/ml of melittin revealed an up-regulation in Drp1 and Mfn1 genes mRNA expression in comparison with control group. Treatment with 32μg/ml of melittin was also associated with a rise in mRNA expression of Drp1 and Mfn1 as compared to the control group.

CONCLUSION

The results of this study showed that melittin has anticancer effects on 4T1 cell lines in a dose and time dependent manner and can be a good candidate for further research on breast cancer treatment.

Animal Venom for Medical Usage in Pharmacopuncture in Korean Medicine: Current Status and Clinical Implication

Animal venoms, widespread throughout the world, are complex mixtures, the composition of which depends on the venom-producing species. The objective of this study was to contribute to the development of animal venom-based medicines by investigating the use of animal venom pharmacopuncture in Korean medicine (KM) institutions. We surveyed 256 public health centers from 1 through 31 October 2019 as guided by the Ministry of Health and Welfare (MoHW). A questionnaire developed by an expert group was distributed and collected for statistical analysis. The survey identified three types of animal venom-based pharmacopuncture: bee, snake, and toad venoms. The medications are based on a single animal venom ingredient and produced in 11 external herbal dispensaries (EHDs). Each animal venom is processed, refined, and freeze-dried in a cleanroom to produce a powder formulation that is later measured, diluted, filtered, filled, sealed, sterilized, and packaged as pharmacopuncture injections used in KM institutions. Bee venom therapy is effective in treating musculoskeletal pain, snake venom therapy is effective in controlling bleeding during surgery, and toad venom therapy is effective in cancer treatment. The study suggests that bee, snake, and toad venoms could be used in medical institutions and have the potential for drug development.

Bee venom attenuates neurodegeneration and motor impairment and modulates the response to L-dopa or rasagiline in a mice model of Parkinson's disease

Objectives

This study aimed to investigate the effect of bee venom, a form of alternative therapy, on rotenone-induced Parkinson's disease (PD) in mice. Moreover, the possible modulation by bee venom of the effect of L-dopa/carbidopa or rasagiline was examined.

Materials and Methods

Rotenone (1.5 mg/kg, subcutaneously; SC) was administered every other day for two weeks and at the same time mice received the vehicle (DMSO, SC), bee venom (0.065, 0.13, and 0.26 mg/kg; intradermal; ID), L-dopa/carbidopa (25 mg/kg, intraperitoneal; IP), L-dopa/carbidopa+bee venom (0.13 mg/kg, ID), rasagiline (1 mg/kg, IP) or rasagiline+bee venom (0.13 mg/kg, ID). Then, wire hanging and staircase tests were performed and mice were euthanized and brains' striata separated. Oxidative stress biomarkers namely, malondialdehyde (MDA), nitric oxide (NO), reduced glutathione (GSH), paraoxonase-1 (PON-1), and total antioxidant capacity (TAC) were measured. Additionally, butyrylcholinesterase (BuChE), monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-α), and dopamine (DA) were evaluated. Brain histopathological changes and caspase-3- expression were done.

Results

Bee venom significantly enhanced motor performance and inhibited rotenone-induced oxidative/nitrosative stress, observed as a reduction in both MDA and NO along with increasing GSH, PON-1, and TAC. Besides, bee venom decreased MCP-1, TNF-α, and caspase-3 expression together with an increase in BuChE activity and DA content.

Conclusion

Bee venom alone or in combination with L-dopa/carbidopa or rasagiline alleviated neuronal degeneration compared with L-dopa/carbidopa or rasagiline treatment only. Bee venom via its antioxidant and cytokine reducing potentials might be of value either alone or as adjunctive therapy in the management of PD.

Clinical Applications of Bee Venom Acupoint Injection

Bee venom is a complex natural mixture with various pharmaceutical properties. Among these properties, its peptides and enzymes have potential medical therapy for pain relief and inflammation. In clinical settings, this therapy has been used widely to treat diseases by injecting into acupoints. In this article, we have conducted various research from PubMed, Cochrane Library, and Clinical Key from inception of July 2020. The results revealed that bee venom therapy has been reported effective in anti-inflammatory, antiapoptosis, and analgesic effects. Moreover, bee venom acupuncture has been commonly used for clinical disorders such as Parkinson disease, neuropathic pain, Alzheimer disease, intervertebral disc disease, spinal cord injury, musculoskeletal pain, arthritis, multiple sclerosis, skin disease and cancer.

Bee Venom Melittin Protects against Cisplatin-Induced Acute Kidney Injury in Mice via the Regulation of M2 Macrophage Activation

Inflammation is an essential biological response that eliminates pathogenic bacteria and repairs tissue after injury. Acute kidney injury (AKI) is associated with systemic and intrarenal inflammation as the inflammatory process decreases renal function and promotes progression to advanced chronic kidney disease. Macrophages are key mediators of the inflammatory response; their activation influences the immune system and may have various effects. Classically activated type I macrophages (M1) produce a variety of pro-inflammatory cytokines at the lesion site. However, anti-inflammatory type II macrophages (M2) are alternatively activated upon exposure to anti-inflammatory cytokines and are associated with wound healing and tissue repair following AKI. Here, we used melittin from bee venom to enhance the polarization of M2 macrophages and promote renal recovery after AKI. Melittin was administered to mice intraperitoneally for 5 days at various concentrations (10, 50, and 100 µg/kg); serum creatinine and blood urea nitrogen (BUN) levels were analyzed 72 h after cisplatin administration to confirm renal dysfunction. Melittin inhibited the cisplatin-induced increase in creatinine and BUN, an indicator of renal dysfunction. The expression of M1 markers (CD16/32) decreased significantly, whereas that of M2 markers (CD206, Arg1nase I) increased after melittin administration. Consistently, tubular necrosis was substantially reduced in melittin-treated mice. Thus, melittin alleviates cisplatin-induced AKI by regulating M2 macrophage expression.

Melittin Exerts Beneficial Effects on Paraquat-Induced Lung Injuries In Mice by Modifying Oxidative Stress and Apoptosis

Melittin (MEL) is a 26-amino acid peptide with numerous biological activities. Paraquat (PQ) is one of the most widely used herbicides, although it is extremely toxic to humans. To date, PQ poisoning has no effective treatment, and therefore the current study aimed to assess for the first time the possible effects of MEL on PQ-induced lung injuries in mice. Mice received a single intraperitoneal (IP) injection of PQ (30 mg/kg), followed by IP treatment with MEL (0.1 and 0.5 mg/kg) twice per week for four consecutive weeks. Histological alterations, oxidative stress, and apoptosis in the lungs were studied. Hematoxylin and eosin (H&E) staining indicated that MEL markedly reduced lung injuries induced by PQ. Furthermore, treatment with MEL increased superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activity, and decreased malonaldehyde (MDA) and nitric oxide (NO) levels in lung tissue homogenates. Moreover, immunohistochemical staining showed that B-cell lymphoma-2 (Bcl-2) and survivin expressions were upregulated after MEL treatment, while Ki-67 expression was downregulated. The high dose of MEL was more effective than the low dose in all experiments. In summary, MEL efficiently reduced PQ-induced lung injuries in mice. Specific pharmacological examinations are required to determine the effectiveness of MEL in cases of human PQ poisoning.

Anti-cancer effect of bee venom on human MDA-MB-231 breast cancer cells using Raman spectroscopy

We demonstrated the apoptotic effect of bee venom (BV) on human MDA-MB-231 breast cancer cells using Raman spectroscopy and principal component analysis (PCA). Biochemical changes in cancer cells were monitored following BV treatment; the results for different concentrations and treatment durations differed markedly. Significantly decreased Raman vibrations for DNA and proteins were observed for cells treated with 3.0 µg/mL BV for 48 h compared with those of control cells. These results suggest denaturation and degradation of proteins and DNA fragmentation (all cell death-related processes). The Raman spectroscopy results agreed with those of atomic force microscopy and conventional biological tests such as viability, TUNEL, and western blot assays. Therefore, Raman spectroscopy, with PCA, provides a noninvasive, label-free tool for assessment of cellular changes on the anti-cancer effect of BV.

Late-Onset Post-radiation Lymphedema Provoked by Bee Venom Therapy: A Case Report

Lymphedema is a common complication associated with cancer itself or with cancer treatment. Lymphedema infrequently occurs after drug therapy. Bee venom is one of the materials used in acupuncture, and it has been used in the treatment of a variety of inflammatory diseases including arthritis. We report a 74-year-old male patient with late-onset post-radiation lymphedema provoked by bee venom therapy. He was free of lymphedema for 5 years after the complete remission of prostate cancer which had been treated with transurethral resection and radiation therapy. The patient developed left leg swelling after undergoing bee venom therapy for left hip pain. Computed tomography and lymphoscintigraphy showed lymphedema without tumor recurrence or infection. The lymphatic system was suspected to be injured by bee venom therapy and lymphedema was provoked. Bee venom therapy should be used cautiously in patients prone to lymphedema.

Anticancer Activity of Toxins from Bee and Snake Venom-An Overview on Ovarian Cancer

Cancer represents the disease of the millennium, a major problem in public health. The proliferation of tumor cells, angiogenesis, and the relationship between the cancer cells and the components of the extracellular matrix are important in the events of carcinogenesis, and these pathways are being used as targets for new anticancer treatments. Various venoms and their toxins have shown possible anticancer effects on human cancer cell lines, providing new perspectives in drug development. In this review, we observed the effects of natural toxins from bee and snake venom and the mechanisms through which they can inhibit the growth and proliferation of cancer cells. We also researched how several types of natural molecules from venom can sensitize ovarian cancer cells to conventional chemotherapy, with many toxins being helpful for developing new anticancer drugs. This approach could improve the efficiency of standard therapies and could allow the administration of decreased doses of chemotherapy. Natural toxins from bee and snake venom could become potential candidates for the future treatment of different types of cancer. It is important to continue these studies concerning therapeutic drugs from natural resource and, more importantly, to investigate their mechanism of action on cancer cells.

Inhibitory effects of bee venom on mast cell-mediated allergic inflammatory responses

Although bee venom (BV) is a toxin that causes bee stings to be painful, it has been widely used clinically for the treatment of certain immune‑associated diseases. BV has been used traditionally for the treatment of chronic inflammatory diseases. In this regard, the present study analyzed the effect of BV on the regulation of inflammatory mediator production by mast cells and their allergic inflammatory responses in an animal model. HMC‑1 cells were treated with BV prior to stimulation with phorbol‑12‑myristate 13‑acetate plus calcium ionophore A23187 (PMACI). The production of allergy‑associated pro‑inflammatory mediators was examined, and the underlying mechanisms were investigated. Furthermore, to investigate whether BV exhibits anti‑inflammatory effects associated with anti‑allergic effects in vivo, a compound 48/80‑induced anaphylaxis model was used. BV inhibited histamine release, mRNA expression and production of cytokines in the PMACI‑stimulated HMC‑1 cells. Furthermore, the inhibitory effects of BV on mitogen‑activated protein kinase (MAPK), MAPK kinase, signal transducer and activator of transcription 3 (STAT3) and Akt were demonstrated. The present study also investigated the ability of BV to inhibit compound 48/80‑induced systemic anaphylaxis in vivo. BV protected the mice against compound 48/80‑induced anaphylactic‑associated mortality. Furthermore, BV suppressed the mRNA expression levels of pro‑inflammatory cytokines, and suppressed the activation of MAPK and STAT3 in this model. These results provide novel insights into the possible role of BV as a modulator for mast cell‑mediated allergic inflammatory disorders.

The Effects of Melittin and Apamin on Airborne Fungi-Induced Chemical Mediator and Extracellular Matrix Production from Nasal Polyp Fibroblasts

Melittin and apamin are the main components of bee venom and they have been known to have anti-inflammatory and anti-fibrotic properties. The aim of this study was to evaluate the effect of melittin and apamin on airborne fungi-induced chemical mediator and extracellular matrix (ECM) production in nasal fibroblasts. Primary nasal fibroblasts were isolated from nasal polyps, which were collected during endoscopic sinus surgery. Nasal fibroblasts were treated with Alternaria and Aspergillus. The effects of melittin and apamin on the production of interleukin (IL)-6 and IL-8 were determined with enzyme linked immunosorbent assay. ECM mRNA and protein expressions were determined with the use of quantitative RT-PCR and Western blot. Alternaria-induced IL-6 and IL-8 production was significantly inhibited by apamin. However, melittin did not influence the production of IL-6 and IL-8 from nasal fibroblasts. Melittin or apamin significantly inhibited collagen type I, TIMP-1, and MMP-9 mRNA expression and protein production from nasal fibroblasts. Melittin and apamin inhibited Alternaria-induced phosphorylation of Smad 2/3 and p38 MAPK. Melittin and apamin can inhibit the fungi-induced production of chemical mediators and ECM from nasal fibroblasts. These results suggest the possible role of melittin and apamin in the treatment of fungi induced airway inflammatory diseases.

Bee venom for the treatment of Parkinson's disease: How far is it possible?

Parkinson's disease (PD) is the second most common neurodegenerative disease, characterized by progressive loss of dopaminergic neurons in the substantia nigra pars compacta leading to depletion of striatal dopamine and motor symptoms as bradykinesia, resting tremors, rigidity, and postural instability. Current therapeutic strategies for PD are mainly symptomatic and may cause motor complications, such as motor fluctuations and dyskinesia. Therefore, alternative medicine may offer an effective adjuvant treatment for PD. Bee venom therapy (BVT) has long been used as a traditional therapy for several conditions, such as rheumatoid arthritis, asthma, and skin diseases. Experimental and clinical studies showed that BVT could be an effective adjuvant treatment for PD. Several mechanisms were suggested for these findings including the ability of BVT to attenuate neuroinflammation, inhibit apoptosis of dopaminergic neurons, protect against glutamate-induced neurotoxicity, and restore normal dopamine levels in the nigrostriatal pathway. In this article, we reviewed and summarized the literature regarding the potential of BVT for the treatment of PD.

Melittin inhibits tumor growth and decreases resistance to gemcitabine by downregulating cholesterol pathway gene CLU in pancreatic ductal adenocarcinoma

Melittin is a Chinese traditional medicine for treating chronic inflammation, immunological diseases and cancers, however, the efficacy of melittin and its mechanism for treating pancreatic ductal adenocarcinoma (PDAC) are still unknown. Here we investigated the anti-cancer activity of melittin and its regulated mechanism(s) in the PDAC models. Melittin was found to suppress tumor growth by promoting cell apoptosis and cell-cycle arrest. Interestingly, the microarray analyses demonstrated that melittin significantly regulated cholesterol biosynthesis pathway during treatment. For instance, the cholesterol pathway gene clusterin (CLU) was highly downregulated by melittin which also enhanced gemcitabine sensitivity in PDAC cells by inhibiting CLU expression. In contrast, overexpression of CLU significantly diminished melittin mediated tumor suppression and gemcitabine sensitization, suggesting that CLU is the target of melittin. Furthermore, in the xenograft mouse model, the combination therapy of melittin and gemcitabine is more efficacious for inhibiting PDAC tumor growth than either single regimen. Taken together, our study has indicated that melittin is capable of suppressing tumor growth and promoting gemcitabine sensitivity in PDAC by downregulating cholesterol pathway.

Effect of bee venom or proplis on molecular and parasitological aspects of Schistosoma mansoni infected mice

The present study was performed to elucidate the efficacy of Apis mellifera L bee venom (BV) or proplis (200 mg/kg orally for three consecutive days) on Schistosoma mansoni infected mice. The results recorded reduction in the total worm burden, numbers of immature eggs and the ova count in hepatic tissue in BV (sting or injection) or proplis treated groups as compared to the infected group. Histological examination illustrated a significant increase (P ≤ 0.05) in the diameter of hepatic granuloma in BV treated groups (272.78 and 266.9, respectively) and a significant decrease in proplis treated mice (229.35) compared with the infected group (260.67). Electrophoretic pattern of RNA showed a decrease in mean of maximal optical density in liver and intestine of S. mansoni infected mice treated with bee venom (sting or injection) as compared with infected group. Flow cytometry analyses of RNA or apoptotic percentage of worms recovered from BV sting (19 and 49 % respectively); BV injected (20.5 and 51.17 %, respectively) and proplis (35 and 23.93 %, respectively) groups were compared with S. mansoni infected group (37.87 and 39.21 %, respectively). It can be concluded that administration of bee venom or proplis are effective in case of S. mansoni infection. Although bee venom cause increase of granuloma diameter and this might be due to venom concentration and further studies are required to avoid such harmful effect.

Anti-Inflammatory Applications of Melittin, a Major Component of Bee Venom: Detailed Mechanism of Action and Adverse Effects

Inflammation is a pervasive phenomenon triggered by the innate and adaptive immune systems to maintain homeostasis. The phenomenon normally leads to recovery from infection and healing, but when not properly phased, inflammation may cause immune disorders. Bee venom is a toxin that bees use for their protection from enemies. However, for centuries it has been used in the Orient as an anti-inflammatory medicine for the treatment of chronic inflammatory diseases. Bee venom and its major component, melittin, are potential means of reducing excessive immune responses and provide new alternatives for the control of inflammatory diseases. Recent experimental studies show that the biological functions of melittin could be applied for therapeutic use in vitro and in vivo. Reports verifying the therapeutic effects of melittin are accumulating in the literature, but the cellular mechanism(s) of the anti-inflammatory effects of melittin are not fully elucidated. In the present study, we review the current knowledge on the therapeutic effects of melittin and its detailed mechanisms of action against several inflammatory diseases including skin inflammation, neuroinflammation, atherosclerosis, arthritis and liver inflammation, its adverse effects as well as future prospects regarding the use of melittin.

Melittin inhibits tumor angiogenesis modulated by endothelial progenitor cells associated with the SDF-1α/CXCR4 signaling pathway in a UMR-106 osteosarcoma xenograft mouse model

Endothelial progenitor cells (EPCs) are important in tumor angiogenesis. Stromal cell-derived factor-1α (SDF-1α) and its receptor C-X-C chemokine receptor type 4 (CXCR4) are key in stem cell homing. Melittin, a component of bee venom, exerts antitumor activity, however, the underlying mechanisms remain to be elucidated. The present study aimed to assess the effects of melittin on EPCs and angiogenesis in a mouse model of osteosarcoma. UMR-106 cells and EPCs were treated with various concentrations of melittin and cell viability was determined using the MTT assay. EPC adherence, migration and tube forming ability were assessed. Furthermore, SDF-1α, AKT and extracellular signal-regulated kinase (ERK)1/2 expression levels were detected by western blotting. Nude mice were inoculated with UMR-106 cells to establish an osteosarcoma mouse model. The tumors were injected with melittin, and its effects were assessed by immunohistochemistry and immunofluorescence. Melittin decreased the viability of UMR-106 cells and EPCs. In addition, it decreased EPC adhesion, migration and tube formation when compared with control and SDF-1α-treated cells. Melittin decreased the expression of phosphorylated (p)-AKT, p-ERK1/2, SDF-1α and CXCR4 in UMR-106 cells and EPCs when compared with the control. The proportions of cluster of differentiation (CD)34/CD133 double-positive cells were 16.4±10.4% in the control, and 7.0±4.4, 2.9±1.2 and 1.3±0.3% in tumors treated with 160, 320 and 640 µg/kg melittin per day, respectively (P<0.05). At 11 days, melittin reduced the tumor size when compared with that of the control (control, 4.8±1.3 cm³; melittin, 3.2±0.6, 2.6±0.5, and 2.0±0.2 cm³ for 160, 320 and 640 µg/kg, respectively; all P<0.05). Melittin decreased the microvessel density, and SDF-1α and CXCR4 protein expression levels in the tumors. Melittin may decrease the effect of osteosarcoma on EPC-mediated angiogenesis, possibly via inhibition of the SDF-1α/CXCR4 signaling pathway.

Bee Venom Phospholipase A2: Yesterday's Enemy Becomes Today's Friend

Bee venom therapy has been used to treat immune-related diseases such as arthritis for a long time. Recently, it has revealed that group III secretory phospholipase A₂ from bee venom (bee venom group III sPLA₂) has in vitro and in vivo immunomodulatory effects. A growing number of reports have demonstrated the therapeutic effects of bee venom group III sPLA₂. Notably, new experimental data have shown protective immune responses of bee venom group III sPLA₂ against a wide range of diseases including asthma, Parkinson’s disease, and drug-induced organ inflammation. It is critical to evaluate the beneficial and adverse effects of bee venom group III sPLA₂ because this enzyme is known to be the major allergen of bee venom that can cause anaphylactic shock. For many decades, efforts have been made to avoid its adverse effects. At high concentrations, exposure to bee venom group III sPLA₂ can result in damage to cellular membranes and necrotic cell death. In this review, we summarized the current knowledge about the therapeutic effects of bee venom group III sPLA₂ on several immunological diseases and described the detailed mechanisms of bee venom group III sPLA₂ in regulating various immune responses and physiopathological changes.

Melittin suppresses cathepsin S-induced invasion and angiogenesis via blocking of the VEGF-A/VEGFR-2/MEK1/ERK1/2 pathway in human hepatocellular carcinoma

Melittin, a significant constituent of Apis mellifera (honeybee) venom, is a water-soluble toxic peptide that has traditionally been used as an antitumor agent. However, the underlying mechanisms by which it inhibits tumor cell growth and angiogenesis remain to be elucidated. In the present study, screening for increased cathepsin S (Cat S) expression levels was performed in MHCC97-H cells and various other hepatocellular carcinoma cell lines by reverse transcription-polymerase chain reaction and western blot analysis. A pcDNA3.1-small hairpin RNA (shRNA)-Cat S vector was stably transfected into MHCC97-H cells (shRNA/MHCC97-H) in order to knockdown the expression of Cat S. The effects resulting from the inhibition of Cat S-induced proliferation, invasion and angiogenesis by melittin were examined using cell proliferation, cell viability, flat plate colony formation, migration, wound healing, Transwell migration and ELISA assays. In order to substantiate the evidence for melittin-mediated inhibition of Cat S-induced angiogenesis, Cat S RNA was transfected into primary human umbilical vein endothelial cells (Cat S-HUVECs) to induce overexpression of the Cat S gene. The effects of melittin on HUVECs were examined using Transwell migration and tube formation assays. The findings demonstrated that melittin was able to significantly suppress MHCC97-H cell (Mock/MHCC97-H) proliferation, invasion and angiogenesis, as well as capillary tube formation of Cat S-HUVECs, in a dose-dependent manner. However, proliferation, invasion and angiogenesis in shRNA/MHCC97-H and in native HUVECs (Mock-HUVECs) were unaffected. In addition, melittin specifically decreased the expression of phosphorylated (activated) Cat S, and components of the vascular endothelial growth factor (VEGF)-A/VEGF receptor 2 (VEGFR-2)/mitogen-activated protein kinase kinase 1 (MEK1)/extracellular signal-regulated kinase (ERK)1/2 signaling pathway in Mock/MHCC97-H cells. In conclusion, the inhibition of tumor cell growth and anti-angiogenic activity exerted by melittin may be associated with anti-Cat S actions, via the inhibition of VEGF-A/VEGFR-2/MEK1/ERK1/2 signaling.

Interleukin-17 promotes angiogenesis by stimulating VEGF production of cancer cells via the STAT3/GIV signaling pathway in non-small-cell lung cancer

The presence of IL-17-positive cells is observed in a variety of inflammatory associated cancers and IL-17 has been found to be involved in angiogenesis. However, it remains unclear how IL-17 might contribute to tumor angiogenesis. In our study, IL-17 enhanced the formation of vessel-like tubes in HUVECs both directly (when HUVECs were incubated with IL-17) and indirectly (when HUVECs were incubated in conditioned cell media (CCM) from IL-17-treated cancer cells). Our results from experiments using siRNA-mediated knockdowns of STAT3 and GIV suggest that the effects of IL-17 were mediated by activating STAT3/GIV signaling in NSCLC cells and subsequently up-regulating its downstream target VEGF. Consistent with these findings, immunostaining experiments on human NSCLC tissues indicated that IL-17 and GIV expression were significantly and positively associated with increased tumor vascularity. The clinical significance of IL-17 was authenticated by our finding that the combination of intratumoral IL-17 + cells and GIV expression served as a better prognosticator for survival than either marker alone. Therefore, our finding highlights a novel aspect of STAT3/GIV pathway in the IL-17 promotes tumor angiogenesis of NSCLC.

Integrated analysis of the ecotoxicological and genotoxic effects of the antimicrobial peptide melittin on Daphnia magna and Pseudokirchneriella subcapitata

Melittin is a major constituent of the bee venom of Apis mellifera with a broad spectrum of activities. Melittin therapeutical potential is subject to its toxicity and the assessment of ecotoxicity and genotoxicity is of particular interest for therapeutic use. Here we analyzed the biological effects of melittin on two aquatic species, which are representative of two different levels of the aquatic trophic chain: the invertebrate Daphnia magna and the unicellular microalgae Pseudokirchneriella subcapitata. The attention was focused on the determination of: i) ecotoxicity; ii) genotoxicity; iii) antigenotoxicity. Our main finding is that melittin is detrimental to D. magna reproduction and its sub-lethal concentrations create an accumulation dependent on exposition times and a negative effect on DNA. We also observed that melittin significantly delayed time to first eggs. Moreover, results showed that melittin exerted its toxic and genotoxic effects in both species, being a bit more aggressive towards P. subcapitata.

Biotoxins for cancer therapy

In recent times, a number of studies have provided evidence that biotoxins present great potential as antitumor agents, such as snake venom, bee venom, some bacteria toxins and plant toxins, and thus could be used as chemotherapeutic agents against tumors. The biodiversity of venoms and toxins make them a unique source from which novel anticancer agent may be developed. Biotoxins, also known as natural toxins, include toxic substances produced by plants, animals and microorganisms. Here, we systematically list representative biological toxins that have antitumor properties, involving animal toxins, plant toxins, mycotoxins as well as bacterial toxins. In this review, we summarize the current knowledge involving biotoxins and the active compounds that have anti-cancer activity to induce cytotoxic, antitumor, immunomodulatory, and apoptotic effects in different tumor cells in vivo or in vitro. We also show insights into the molecular and functional evolution of biotoxins.

Recombinant human kallistatin inhibits angiogenesis by blocking VEGF signaling pathway

Kallistatin has been recognized as an endogenous angiogenic inhibitor. However, the underlying molecular mechanism remains poorly understood. Taking it into account that vascular endothelial growth factor (VEGF) has been implicated in all aspects of normal and pathological vasculogenesis and angiogenesis. In this study, we investigated whether VEGF signaling pathway was impacted by the anti-angiogenic effect of recombinant human kallistatin (rhKal). We found that the rhKal inhibited proliferation as well as induced apoptosis of cultured human umbilical vein endothelial cells (HUVECs) in both concentration- and time-dependent manners. The rhKal also suppressed the VEGF-induced migration and tube formation of HUVECs. Furthermore, our data revealed that the rhKal suppressed the VEGF165-stimulated tyrosine phosphorylation of VEGFR-2 as well as its downstream signal molecular activation. The inhibition of receptor phosphorylation was correlated with a decrease in VEGF-triggered phosphorylation of angiogenesis signal molecules AKT and ERK, but not stress-related JNK. Taken together, these findings added the knowledge for us to understand the anti-angiogenic mechanism of kallistatin, which suggested that the rhKal could be worth as a candidate compound for further development for the purpose of anti-angiogenic therapies.

A novel compound T7 (N-{4'-[(1E)-N-hydroxyethanimidoyl]-3',5,6-trimethoxybiphenyl-3-yl}-N'-[4-(3-morpholin-4-ylpropoxy)phenyl]urea) screened by tissue angiogenesis model and its activity evaluation on anti-angiogenesis

A tissue model for angiogenesis that imitated new blood vessels formation in vivo had been established in the previous study. Here, it was used to screen and evaluate a series of synthesized compounds and the results indicated that compound T7 (N-{4'-[(1E)-N-hydroxyethanimidoyl]-3',5,6-trimethoxybiphenyl-3-yl}-N'-[4-(3-morpholin-4-ylpropoxy)phenyl]urea) could effectively inhibit the blood vessels formation. Then the anti-angiogenic potential of T7 and its related molecular mechanisms against lung carcinoma in vitro and in vivo were investigated. Treatment with T7 significantly inhibited human umbilical vein endothelial cells and A549 cells proliferation and migration. T7 reduced human umbilical vein endothelial cells tube formation as well. Western blotting analysis of cell signaling molecules indicated that T7 reduced phosphorylation of KDR and its downstream signaling players AKT and ERK1/2 activation in endothelial cells and A549 cells. Moreover, T7 inhibited tumor growth in A549 xenografted model of athymic mice and reduced CD34 expression levels in tumor-bearing mice by immunohistochemistry. In sum, our findings showed that T7 was a candidate of tumor angiogenesis inhibitors, and it functioned by interrupting the autophosphorylation of KDR, AKT and ERK1/2.

Anti-tumor effects of melittin

Melittin is a major active component of bee venom, and it exhibits strong biological activity. Recent reports have demonstrated that melittin has anti-tumor effects on many kinds of tumor cells through direct interaction with cell transduction mediators and influencing cellular signaling pathways, induction of apoptotic or necrotic cell death, and inhibition of growth and proliferationin vivo or in vitro. Nanotechnology and genetic engineering provide technical support to the safe and targeted delivery of melittin to the body. This review summarizes recent findings on the anti-tumor potential of melittin in tumors of different types.

Cancer cell growth inhibitory effect of bee venom via increase of death receptor 3 expression and inactivation of NF-kappa B in NSCLC cells

Our previous findings have demonstrated that bee venom (BV) has anti-cancer activity in several cancer cells. However, the effects of BV on lung cancer cell growth have not been reported. Cell viability was determined with trypan blue uptake, soft agar formation as well as DAPI and TUNEL assay. Cell death related protein expression was determined with Western blotting. An EMSA was used for nuclear factor kappaB (NF-κB) activity assay. BV (1–5 μg/mL) inhibited growth of lung cancer cells by induction of apoptosis in a dose dependent manner in lung cancer cell lines A549 and NCI-H460. Consistent with apoptotic cell death, expression of DR3 and DR6 was significantly increased. However, deletion of DRs by small interfering RNA significantly reversed BV induced cell growth inhibitory effects. Expression of pro-apoptotic proteins (caspase-3 and Bax) was concomitantly increased, but the NF-κB activity and expression of Bcl-2 were inhibited. A combination treatment of tumor necrosis factor (TNF)-like weak inducer of apoptosis, TNF-related apoptosis-inducing ligand, docetaxel and cisplatin, with BV synergistically inhibited both A549 and NCI-H460 lung cancer cell growth with further down regulation of NF-κB activity. These results show that BV induces apoptotic cell death in lung cancer cells through the enhancement of DR3 expression and inhibition of NF-κB pathway.

Anti-genotoxicity and anti-mutagenicity of Apis mellifera venom

The search for substances able to inhibit and/or diminish the effects of genotoxic and mutagenic substances has been the target of several investigations performed in recent times. Hymenoptera venoms constitute a considerable source of substances with pharmacological potential. The present study aimed to evaluate the cytotoxic, genotoxic and anti-genotoxic, mutagenic and anti-mutagenic potentials of Apis mellifera venom in HepG2 cells. In this evaluation, the MTT test was applied to determine the most appropriate concentrations for the genotoxicity and mutagenicity tests. It was verified that the concentrations of 0.1, 0.05 and 0.01μg/mL were not cytotoxic, hence these concentrations were used in the experiments. For the evaluation of the genotoxic and mutagenic potential of the bee venom the comet assay and the micronucleus test were applied, respectively. The concentrations mentioned above presented both genotoxic and mutagenic potential for HepG2 cells and it was necessary to test lower concentrations of the venom (10pg/mL, 1pg/mL and 0.1pg/mL) for the anti-genotoxicity and anti-mutagenicity tests, which were performed subjecting the cells to the action of MMS (methyl methanesulfonate) in order to verify the ability of the venom to inhibit or diminish the action of this compound, which has a recognized action on the genetic material. Pre-, post-treatment and simultaneous treatment with and without incubation with the venom were performed. It was observed that the lowest three concentrations tested did not present any anti-genotoxic and anti-mutagenic activity on the cells. The use of bee venom for pharmacological purposes in treatments such as cancer must be done with extreme caution, since it was observed that even at very low concentrations the venom can induce genotoxicity and mutagenicity in human cells, as was verified for the HepG2 cells.

Effect of bee venom on IL-6, COX-2 and VEGF levels in polycystic ovarian syndrome induced in Wistar rats by estradiol valerate

BACKGROUND

Polycystic ovarian syndrome (PCOS) is a low-grade inflammatory disease characterized by hyperandrogenemia, hirsutism, chronic anovulation and vascular disorder. Interleukin-6 (IL-6), cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) are triggered by inflammatory stimuli and lead to angiogenesis and pathogenesis of the ovary. Honeybee venom (HBV) contains an array of biologically active components possessing various pharmaceutical properties. This study was designed to assess the possibility of HBV application as an anti-inflammatory therapeutic agent to suppress levels of the main inflammatory mediators IL-6, COX-2 and VEGF.To induce PCOS, 1 mg of estradiol valerate (EV) per 100 g of body weight was subcutaneously (SC) injected into eight-week-old rats. After 60 days, 0.5 mg/kg of HBV was administered Intraperitoneal (IP) for 14 consecutive days, and the results of PCOS treatment were investigated. Rats were then anesthetized with CO2, and the ovaries were surgically removed. Serum IL-6 was detected by the ELISA kit. Immunoexpression of COX-2 and VEGF were examined in three groups: EV-induced PCOS, HBV-treated PCOS and control animals.

RESULTS

Thickness of theca layer, number and diameter of cysts and levels of IL-6 significantly decreased in HBV group relative to PCOS group. The immunohistochemical analysis showed an increase in COX-2 and VEGF expression in PCOS group whereas HBV-treated rats presented weak and irregular immunostaining.

CONCLUSIONS

Our results suggest that the beneficial effect of HBV may be mediated through its inhibitory effect on serum IL-6 level and ovarian COX-2 and VEGF expression.

Conus vexillum venom induces oxidative stress in Ehrlich's ascites carcinoma cells: an insight into the mechanism of induction

BACKGROUND

It is estimated that venoms of marine cone snails (genus Conus) contain more than 100,000 different small peptides with a wide range of pharmacological and biological actions. Some of these peptides were developed into potential therapeutic agents and as molecular tools to understand biological functions of nervous and cardiovascular systems. In this study we examined the cytotoxic and anticancer properties of the marine vermivorous cone snail Conus vexillum (collected from Hurgada and Sharm El-Shaikh, Red Sea, Egypt) and suggest the possible mechanisms involved. The in vitro cytotoxic effects of Conus venom were assessed against Ehrlich's ascites carcinoma (EAC) cells.

RESULTS

Conus venom treatment resulted in concentration-dependent cytotoxicity as indicated by a lactate dehydrogenase leakage assay. Apoptotic effects were measured in vivo by measuring levels of reactive oxygen species and oxidative defense agents in albino mice injected with EAC cells. Conus venom (1.25 mg/kg) induced a significant increase (p < 0.05) in several oxidative stress biomarkers (lipid peroxidation, protein carbonyl content and reactive nitrogen intermediates) of EAC cells after 3, 6, 9 and 12 hours of venom injection. Conus venom significantly reduced (p < 0.05) the activities of oxidative defense enzymes (catalase and superoxide dismutase) as well as the total antioxidant capacity of EAC cells, as evidenced by lowered levels of reduced glutathione.

CONCLUSIONS

These results demonstrate the cytotoxic potential of C. vexillum venom by inducing oxidative stress mediated mechanisms in tumor cells and suggest that the venom contains novel molecules with potential anticancer activity.

Melittin peptide kills Trypanosoma cruzi parasites by inducing different cell death pathways

Antimicrobial peptides (AMPs) are components of the innate immune response that represent desirable alternatives to conventional pharmaceuticals, as they have a fast mode of action, a low likelihood of resistance development and can act in conjunction with existing drug regimens. AMPs exhibit strong inhibitory activity against both Gram-positive and Gram-negative bacteria, fungi, viruses, metazoans and other parasites, such as the protozoan Leishmania. Melittin is a naturally occurring AMP, which comprises 40-50% of the dry weight of Apis mellifera venom. Our group has recently shown that crude A. mellifera venom is lethal to Trypanosoma cruzi, the Chagas disease etiologic agent, and generates a variety of cell death phenotypes among treated parasites. Here, we demonstrate that the melittin affected all of T. cruzi developmental forms, including the intracellular amastigotes. The ultrastructural changes induced by melittin suggested the occurrence of different programmed cell death pathways, as was observed in A. mellifera-treated parasites. Autophagic cell death appeared to be the main death mechanism in epimastigotes. In contrast, melittin-treated trypomastigotes appeared to be dying via an apoptotic mechanism. Our findings confirm the great potential of AMPs, including melittin, as a potential source of new drugs for the treatment of neglected diseases, such as Chagas disease.

Apis mellifera venom induces different cell death pathways in Trypanosoma cruzi

Chagas disease chemotherapy is based on drugs that exhibit toxic effects and have limited efficacy, such as Benznidazole. Therefore, research into new chemotherapeutic agents from natural sources needs to be exploited. Apis mellifera venom consists of many biologically active molecules and has been reported to exhibit remarkable anti-cancer effects, often promoting an apoptosis-like death phenotype. This study demonstrates that A. mellifera venom can affect the growth, viability and ultrastructure of all Trypanosoma cruzi developmental forms, including intracellular amastigotes, at concentrations 15- to 100-fold lower than those required to cause toxic effects in mammalian cells. The ultrastructural changes induced by the venom in the different developmental forms led us to hypothesize the occurrence of different programmed cell death pathways. Autophagic cell death, characterized by the presence of autophagosomes-like organelles and a strong monodansyl cadaverine labelling, appears to be the main death mechanism in epimastigotes. In contrast, increased TUNEL staining, abnormal nuclear chromatin condensation and kDNA disorganization was observed in venom-treated trypomastigotes, suggesting cell death by an apoptotic mechanism. On the other hand, intracellular amastigotes presented a heterogeneous cell death phenotype profile, where apoptosis-like death seemed to be predominant. Our findings confirm the great potential of A. mellifera venom as a source for the development of new drugs for the treatment of neglected diseases such as Chagas disease.

Melittin suppresses VEGF-A-induced tumor growth by blocking VEGFR-2 and the COX-2-mediated MAPK signaling pathway

Melittin (1) is a major polypeptide in honey bee venom that has been used traditionally against chronic inflammation and cancer. However, its molecular mechanism has not been determined. In this study, the antitumor effect of 1 was compared with that of NS398, a cyclooxygenase-2 (COX-2) inhibitor, in vivo and in vitro. Subcutaneous injection of 1 at 0.5 and 5 mg/kg suppressed significantly vascular endothelial growth factor (VEGF)-A-transfected highly metastatic Lewis lung cancer (VEGF-A-hm LLC) tumor growth by 25% and 57%, respectively. Also, 1 inhibited significantly the number of vessels around VEGF-A-hm LLC cells. The results were superior to those obtained in the mice treated with NS398. Compound 1 dose-dependently inhibited proliferation and tube formation in human umbilical vein endothelial cells (VEGF-A-HUVECs), without affecting cell viability in native HUVECs. In addition, 1 decreased the expression of VEGF receptor-2 (VEGFR-2), COX-2, and prostaglandin E2 (PGE2) in VEGF-A-transfected HUVECs. These effects were accompanied by a reduction of the phosphorylation of extracellular signal-regulated kinase 1/2 and c-jun N-terminal kinase, whereas it increased the phosphorylation of p38 mitogen-activated protein kinase (MAPK). SB203580 abolished the downregulation of COX-2 and VEGFR-2 and the inhibition of cell proliferation by 1. The antitumor activity of 1 may be associated with antiangiogenic actions via inhibiting VEGFR-2 and inflammatory mediators involved in the MAPK signaling pathway.

A novel angiogenesis inhibitor impairs lovo cell survival via targeting against human VEGFR and its signaling pathway of phosphorylation

Colorectal cancer represents the fourth commonest malignancy, and constitutes a major cause of significant morbidity and mortality among other diseases. However, the chemical therapy is still under development. Angiogenesis plays an important role in colon cancer development. We developed HMQ18–22 (a novel analog of taspine) with the aim to target angiogenesis. We found that HMQ18–22 significantly reduced angiogenesis of chicken chorioallantoic membrane (CAM) and mouse colon tissue, and inhibited cell migration and tube formation as well. Then, we verified the interaction between HMQ18–22 and VEGFR2 by AlphaScreen P-VEGFR assay, screened the targets on angiogenesis by VEGF Phospho Antibody Array, validated the target by western blot and RNAi in lovo cells. We found HMQ18–22 could decrease phosphorylation of VEGFR2(Tyr¹²¹⁴), VEGFR1(Tyr¹³³³), Akt(Tyr³²⁶), protein kinase Cα (PKCα) (Tyr⁶⁵⁷) and phospholipase-Cγ-1 (PLCγ-1) (Tyr⁷⁷¹). Most importantly, HMQ18–22 inhibited proliferation of lovo cell and tumor growth in a human colon tumor xenografted model of athymic mice. Compared with normal lovo cells proliferation, the inhibition on proliferation of knockdown cells (VEGFR2, VEGFR1, Akt, PKCα and PLCγ-1) by HMQ18–22 decreased. These results suggested that HMQ18–22 is a novel angiogenesis inhibitor and can be a useful therapeutic candidate for colon cancer intervention.