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Authors = Sok Cheon Pak

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Open AccessArticle Emulsion-Based Intradermal Delivery of Melittin in Rats
Molecules 2017, 22(5), 836; doi:10.3390/molecules22050836
Received: 14 March 2017 / Revised: 16 May 2017 / Accepted: 16 May 2017 / Published: 19 May 2017
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Abstract
Bee venom (BV) has long been used as a traditional medicine. The aim of the present study was to formulate a BV emulsion with good rheological properties for dermal application and investigate the effect of formulation on the permeation of melittin through dermatomed
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Bee venom (BV) has long been used as a traditional medicine. The aim of the present study was to formulate a BV emulsion with good rheological properties for dermal application and investigate the effect of formulation on the permeation of melittin through dermatomed rat skin. A formulated emulsion containing 1% (w/v) BV was prepared. The emulsion was compared with distilled water (DW) and 25% (w/v) N-methyl-2-pyrrolidone (NMP) in DW. Permeation of melittin from aqueous solution through the dermatomed murine skin was evaluated using the Franz diffusion cells. Samples of receptor cells withdrawn at pre-determined time intervals were measured for melittin amount. After the permeation study, the same skin was used for melittin extraction. In addition, a known amount of melittin (5 μg/mL) was added to stratum corneum, epidermis, and dermis of the rat skin, and the amount of melittin was measured at pre-determined time points. The measurement of melittin from all samples was done with HPLC-MS/MS. No melittin was detected in the receptor phase at all time points in emulsion, DW, or NMP groups. When the amount of melittin was further analyzed in stratum corneum, epidermis, and dermis from the permeation study, melittin was still not detected. In an additional experiment, the amount of melittin added to all skin matrices was corrected against the amount of melittin recovered. While the total amount of melittin was retained in the stratum corneum, less than 10% of melittin remained in epidermis and dermis within 15 and 30 min, respectively. Skin microporation with BV emulsion facilitates the penetration of melittin across the stratum corneum into epidermis and dermis, where emulsified melittin could have been metabolized by locally-occurring enzymes. Full article
(This article belongs to the Special Issue Bioactive Natural Peptides As A Pipeline For Therapeutics)
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Open AccessReview The Pathogenetic Effect of Natural and Bacterial Toxins on Atopic Dermatitis
Toxins 2017, 9(1), 3; doi:10.3390/toxins9010003
Received: 22 August 2016 / Revised: 15 December 2016 / Accepted: 19 December 2016 / Published: 23 December 2016
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Abstract
Atopic dermatitis (AD) is a common allergic skin disease that is associated with chronic, recurrent eczematous and pruritic lesions at the flexural folds caused by interacting factors related to environmental and immune system changes. AD results in dry skin, and immunoglobulin E-mediated allergic
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Atopic dermatitis (AD) is a common allergic skin disease that is associated with chronic, recurrent eczematous and pruritic lesions at the flexural folds caused by interacting factors related to environmental and immune system changes. AD results in dry skin, and immunoglobulin E-mediated allergic reactions to foods and environmental allergens. While steroids and anti-histamines temporarily relieve the symptoms of AD, the possibility of side effects from pharmacological interventions remains. Despite intensive research, the underlying mechanisms for AD have not been clarified. A study of Staphylococcus aureus (S. aureus) established the role of its toxins in the pathogenesis of AD. Approximately 90% of patients with AD experience S. aureus colonization and up to 50%–60% of the colonizing S. aureus is toxin-producing. Any damage to the protective skin barrier allows for the entry of invading allergens and pathogens that further drive the pathogenesis of AD. Some natural toxins (or their components) that have therapeutic effects on AD have been studied. In addition, recent studies on inflammasomes as one component of the innate immune system have been carried out. Additionally, studies on the close relationship between the activation of inflammasomes and toxins in AD have been reported. This review highlights the literature that discusses the pathogenesis of AD, the role of toxins in AD, and the positive and negative effects of toxins on AD. Lastly, suggestions are made regarding the role of inflammasomes in AD. Full article
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Open AccessEditorial An Introduction to the Toxins Special Issue on “Bee and Wasp Venoms: Biological Characteristics and Therapeutic Application”
Toxins 2016, 8(11), 315; doi:10.3390/toxins8110315
Received: 14 October 2016 / Accepted: 19 October 2016 / Published: 28 October 2016
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Open AccessArticle Antibacterial Activity and Antibiotic-Enhancing Effects of Honeybee Venom against Methicillin-Resistant Staphylococcus aureus
Molecules 2016, 21(1), 79; doi:10.3390/molecules21010079
Received: 7 November 2015 / Revised: 4 January 2016 / Accepted: 8 January 2016 / Published: 12 January 2016
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Abstract
Methicillin-resistant Staphylococcus aureus (MRSA), along with other antibiotic resistant bacteria, has become a significant social and clinical problem. There is thus an urgent need to develop naturally bioactive compounds as alternatives to the few antibiotics that remain effective. Here we assessed the in
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Methicillin-resistant Staphylococcus aureus (MRSA), along with other antibiotic resistant bacteria, has become a significant social and clinical problem. There is thus an urgent need to develop naturally bioactive compounds as alternatives to the few antibiotics that remain effective. Here we assessed the in vitro activities of bee venom (BV), alone or in combination with ampicillin, penicillin, gentamicin or vancomycin, on growth of MRSA strains. The antimicrobial activity of BV against MRSA strains was investigated using minimum inhibitory concentrations (MIC), minimum bactericidal concentrations (MBC) and a time-kill assay. Expression of atl which encodes murein hydrolase, a peptidoglycan-degrading enzyme involved in cell separation, was measured by reverse transcription-polymerase chain reaction. The MICs of BV were 0.085 µg/mL and 0.11 µg/mL against MRSA CCARM 3366 and MRSA CCARM 3708, respectively. The MBC of BV against MRSA 3366 was 0.106 µg/mL and that against MRSA 3708 was 0.14 µg/mL. The bactericidal activity of BV corresponded to a decrease of at least 3 log CFU/g cells. The combination of BV with ampicillin or penicillin yielded an inhibitory concentration index ranging from 0.631 to 1.002, indicating a partial and indifferent synergistic effect. Compared to ampicillin or penicillin, both MRSA strains were more susceptible to the combination of BV with gentamicin or vancomycin. The expression of atl gene was increased in MRSA 3366 treated with BV. These results suggest that BV exhibited antibacterial activity and antibiotic-enhancing effects against MRSA strains. The atl gene was increased in MRSA exposed to BV, suggesting that cell division was interrupted. BV warrants further investigation as a natural antimicrobial agent and synergist of antibiotic activity. Full article
(This article belongs to the Special Issue Natural Toxins)
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Open AccessReview The Protective Effect of Bee Venom on Fibrosis Causing Inflammatory Diseases
Toxins 2015, 7(11), 4758-4772; doi:10.3390/toxins7114758
Received: 14 August 2015 / Revised: 24 October 2015 / Accepted: 5 November 2015 / Published: 16 November 2015
Cited by 3 | Viewed by 1205 | PDF Full-text (416 KB) | HTML Full-text | XML Full-text
Abstract
Bee venom therapy is a treatment modality that may be thousands of years old and involves the application of live bee stings to the patient’s skin or, in more recent years, the injection of bee venom into the skin with a hypodermic needle.
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Bee venom therapy is a treatment modality that may be thousands of years old and involves the application of live bee stings to the patient’s skin or, in more recent years, the injection of bee venom into the skin with a hypodermic needle. Studies have proven the effectiveness of bee venom in treating pathological conditions such as arthritis, pain and cancerous tumors. However, there has not been sufficient review to fully elucidate the cellular mechanisms of the anti-inflammatory effects of bee venom and its components. In this respect, the present study reviews current understanding of the mechanisms of the anti-inflammatory properties of bee venom and its components in the treatment of liver fibrosis, atherosclerosis and skin disease. Full article
Open AccessArticle Effects of Melittin Treatment in Cholangitis and Biliary Fibrosis in a Model of Xenobiotic-Induced Cholestasis in Mice
Toxins 2015, 7(9), 3372-3387; doi:10.3390/toxins7093372
Received: 23 June 2015 / Revised: 13 August 2015 / Accepted: 20 August 2015 / Published: 25 August 2015
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Abstract
Cholangiopathy is a chronic immune-mediated disease of the liver, which is characterized by cholangitis, ductular reaction and biliary-type hepatic fibrosis. There is no proven medical therapy that changes the course of the disease. In previous studies, melittin was known for attenuation of hepatic
[...] Read more.
Cholangiopathy is a chronic immune-mediated disease of the liver, which is characterized by cholangitis, ductular reaction and biliary-type hepatic fibrosis. There is no proven medical therapy that changes the course of the disease. In previous studies, melittin was known for attenuation of hepatic injury, inflammation and hepatic fibrosis. This study investigated whether melittin provides inhibition on cholangitis and biliary fibrosis in vivo. Feeding 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) to mice is a well-established animal model to study cholangitis and biliary fibrosis. To investigate the effects of melittin on cholangiopathy, mice were fed with a 0.1% DDC-containing diet with or without melittin treatment for four weeks. Liver morphology, serum markers of liver injury, cholestasis markers for inflammation of liver, the degree of ductular reaction and the degree of liver fibrosis were compared between with or without melittin treatment DDC-fed mice. DDC feeding led to increased serum markers of hepatic injury, ductular reaction, induction of pro-inflammatory cytokines and biliary fibrosis. Interestingly, melittin treatment attenuated hepatic function markers, ductular reaction, the reactive phenotype of cholangiocytes and cholangitis and biliary fibrosis. Our data suggest that melittin treatment can be protective against chronic cholestatic disease in DDC-fed mice. Further studies on the anti-inflammatory capacity of melittin are warranted for targeted therapy in cholangiopathy. Full article
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Open AccessArticle Anti-Fibrotic Effect of Natural Toxin Bee Venom on Animal Model of Unilateral Ureteral Obstruction
Toxins 2015, 7(6), 1917-1928; doi:10.3390/toxins7061917
Received: 22 December 2014 / Revised: 27 April 2015 / Accepted: 1 May 2015 / Published: 29 May 2015
Cited by 2 | Viewed by 1422 | PDF Full-text (4328 KB) | HTML Full-text | XML Full-text
Abstract
Progressive renal fibrosis is the final common pathway for all kidney diseases leading to chronic renal failure. Bee venom (BV) has been widely used as a traditional medicine for various diseases. However, the precise mechanism of BV in ameliorating the renal fibrosis is
[...] Read more.
Progressive renal fibrosis is the final common pathway for all kidney diseases leading to chronic renal failure. Bee venom (BV) has been widely used as a traditional medicine for various diseases. However, the precise mechanism of BV in ameliorating the renal fibrosis is not fully understood. To investigate the therapeutic effects of BV against unilateral ureteral obstruction (UUO)-induced renal fibrosis, BV was given intraperitoneally after ureteral ligation. At seven days after UUO surgery, the kidney tissues were collected for protein analysis and histologic examination. Histological observation revealed that UUO induced a considerable increase in the number of infiltrated inflammatory cells. However, BV treatment markedly reduced these reactions compared with untreated UUO mice. The expression levels of TNF-α and IL-1β were significantly reduced in BV treated mice compared with UUO mice. In addition, treatment with BV significantly inhibited TGF-β1 and fibronectin expression in UUO mice. Moreover, the expression of α-SMA was markedly withdrawn after treatment with BV. These findings suggest that BV attenuates renal fibrosis and reduces inflammatory responses by suppression of multiple growth factor-mediated pro-fibrotic genes. In conclusion, BV may be a useful therapeutic agent for the prevention of fibrosis that characterizes progression of chronic kidney disease. Full article

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