RESUMEN

Bee venom phospholipase A2 (bvPLA2) has been reported to have therapeutic effects such as neuroprotection, anti-inflammation, anti-nociception, anti-cancer properties, caused by increasing regulatory T cells (Tregs). The mechanism of Tregs modulation by bvPLA2 has been demonstrated by binding with the mannose receptor, CD206 in experimental models of several diseases. However, it remains unknown whether this mechanism can also be applied in human blood. In this study, we collected peripheral blood samples from healthy donors and analyzed the percentages of monocyte-derived dendritic cells with CD206 (CD206+ DCs) before expansion, the proportion of Tregs, and the subpopulations after expansion treated with bvPLA2 or PBS using flow cytometry and the correlations among them. The percentage of Tregs tended to be higher in the bvPLA2 group than in the control group. There were significant positive correlations between the CD206 population in hPBMC and the proportions of Tregs treated with bvPLA2, especially in the Treg fold change comparing the increase ratio of Tregs in bvPLA2 and in PBS. These findings indicate that bvPLA2 increased the proportion of Tregs in healthy human peripheral blood and the number of CD206+ DCs could be a predictor of the bvPLA2 response of different individuals.

Asunto(s)

Venenos de Abeja/enzimología , Fosfolipasas A2/farmacología , Linfocitos T Reguladores/efectos de los fármacos , Adulto , Anciano , Venenos de Abeja/farmacología , Femenino , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Masculino , Receptor de Manosa/metabolismo , Persona de Mediana Edad , Receptores de Superficie Celular/metabolismo

RESUMEN

Bee venom phospholipase A2 is a lipolytic enzyme in bee venom that catalyzes hydrolysis of the sn-2 ester bond of membrane phospholipids to produce free fatty acid and lysophospholipids. Current evidence suggests that bee venom phospholipase A2 (bvPLA2) induces regulatory T cell expansion and attenuates several immune system-related diseases, including Alzheimer's disease. The induction of Treg cells is directly mediated by binding to mannose receptors on dendritic cells. This interaction induces the PGE2-EP2 signaling pathway, which promotes Treg induction in CD4+ T cells. In this study, we investigated the effects of bvPLA2 treatment on the apoptotic signaling pathway in Treg populations. Flow cytometry was performed to identify early apoptotic cells. As a result, early apoptotic cells were dramatically decreased in bvPLA2-treated splenocytes, whereas rapamycin-treated cells showed levels of apoptotic cells similar to those of PBS-treated cells. Furthermore, bvPLA2 treatment increased expression of anti-apoptotic molecules including CTLA-4 and PD-1. The survival rate increased in bvPLA2-treated Tregs. Our findings indicate that bvPLA2-mediated modulation of apoptotic signaling is strongly associated with the Treg induction, which exhibits protective effects against various immune-related diseases. To our knowledge, this study is the first to demonstrate that bvPLA2 is the major bee venom (BV) compound capable of inducing Treg expansion through altering apoptotic signal.

Asunto(s)

Apoptosis/efectos de los fármacos , Venenos de Abeja/enzimología , Fosfolipasas A2/farmacología , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Animales , Apoptosis/inmunología , Venenos de Abeja/farmacología , Antígenos CD4/inmunología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/inmunología , Células Cultivadas , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Factor Nuclear 3-gamma del Hepatocito/genética , Factor Nuclear 3-gamma del Hepatocito/inmunología , Subunidad alfa del Receptor de Interleucina-2/inmunología , Lectinas Tipo C/inmunología , Lectinas Tipo C/metabolismo , Masculino , Receptor de Manosa , Lectinas de Unión a Manosa/inmunología , Lectinas de Unión a Manosa/metabolismo , Ratones , Ratones Transgénicos , Receptores de Superficie Celular/inmunología , Receptores de Superficie Celular/metabolismo , Bazo/citología , Bazo/efectos de los fármacos , Bazo/inmunología , Linfocitos T Reguladores/patología

RESUMEN

Parkinson's disease (PD) is the second most common neurodegenerative disorder worldwide. Progressive loss of dopaminergic neurons in the substantia nigra (SN) and their synaptic terminal connections in the striatum are main characterizations of PD. Although many efforts have been made to develop therapeutics, no treatment has been proven effective. We previously demonstrated that bvPLA2 can protect dopaminergic neurons by modulating neuroinflammatory responses in an MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine)-induced mouse model of PD. The cellular basis for the neuroprotective response of bvPLA2 was the induction of CD4+CD25+ regulatory T cells (Tregs), a population known to suppress immune activation and maintain homeostasis and tolerance to self-antigen. The aim of the present study was to investigate the effects of different routes of bvPLA2 administration in a PD mouse model. Neurobehavioral assessment revealed progressive deterioration in locomotor functions of the MPTP group compared with the control group. However, such functions were improved following subcutaneous (s.c.) bvPLA2 administration. The results showed that the s.c. route of bvPLA2 administration contributed to the induction of Treg cells and the reduction of Th1 and Th17 populations, demonstrating that the neuroprotective effects were associated with reduced tyrosine hydroxylase (TH)-positive dopaminergic neurons and microglia. These results suggested that the s.c. bvPLA2 injection could be beneficial for treating aspects of PD.

RESUMEN

Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by highly pruritic, erythematous, and eczematous skin plaques. We previously reported that phospholipase A2 (PLA2) derived from bee venom alleviates AD-like skin lesions induced by 2,4-dinitrochlorobenzene (DNCB) and house dust mite extract (Dermatophagoides farinae extract, DFE) in a murine model. However, the underlying mechanisms of PLA2 action in actopic dermatitis remain unclear. In this study, we showed that PLA2 treatment inhibited epidermal thickness, serum immunoglobulin E (IgE) and cytokine levels, macrophage and mast cell infiltration in the ear of an AD model induced by DFE and DNCB. In contrast, these effects were abrogated in CD206 mannose receptor-deficient mice exposed to DFE and DNCB in the ear. These data suggest that bvPLA2 alleviates atopic skin inflammation via interaction with CD206.

Asunto(s)

Antiinflamatorios/uso terapéutico , Venenos de Abeja/enzimología , Dermatitis Atópica/tratamiento farmacológico , Lectinas Tipo C/metabolismo , Lectinas de Unión a Manosa/metabolismo , Fosfolipasas A2/uso terapéutico , Receptores de Superficie Celular/metabolismo , Animales , Antiinflamatorios/farmacología , Citocinas/sangre , Dermatitis Atópica/metabolismo , Dinitroclorobenceno , Inmunoglobulina E/sangre , Lectinas Tipo C/genética , Masculino , Receptor de Manosa , Lectinas de Unión a Manosa/genética , Ratones Endogámicos C57BL , Ratones Noqueados , Fosfolipasas A2/farmacología , Pyroglyphidae , Receptores de Superficie Celular/genética

RESUMEN

Atopic dermatitis (AD) is a biphasic inflammatory skin disease that is provoked by epidermal barrier defects, immune dysregulation, and increased skin infections. Previously, we have demonstrated that bvPLA2 evoked immune tolerance by inducing regulatory T cells (Treg), and thus alleviated Th2 dominant allergic asthma in mice. Here, we would like to determine whether treatment with bvPLA2 exacerbates the AD-like allergic inflammations induced by house dust mite extract (DFE) in a murine model. Epidermal thickness, immune cell infiltration, serum immunoglobulin, and cytokines were measured. Ear swelling, skin lesions, and the levels of total serum IgE and Th1/Th2 cytokines were elevated in DFE/DNCB-induced AD mice. Topical application of bvPLA2 elicited significant suppression of the increased AD symptoms, including ear thickness, serum IgE concentration, inflammatory cytokines, and histological changes. Furthermore, bvPLA2 treatment inhibited mast cell infiltration into the ear. On the other hand, Treg cell depletion abolished the anti-atopic effects of bvPLA2, suggesting that the effects of bvPLA2 depend on the existence of Tregs. Taken together, the results revealed that topical exposure to bvPLA2 aggravated atopic skin inflammation, suggesting that bvPLA2 might be a candidate for the treatment of AD.

Asunto(s)

Antialérgicos/farmacología , Venenos de Abeja/enzimología , Dermatitis Atópica/tratamiento farmacológico , Dermatophagoides farinae/inmunología , Proteínas de Insectos/farmacología , Fosfolipasas A2/farmacología , Animales , Antialérgicos/aislamiento & purificación , Quimiotaxis de Leucocito/efectos de los fármacos , Citocinas/inmunología , Citocinas/metabolismo , Dermatitis Atópica/sangre , Dermatitis Atópica/inmunología , Dermatitis Atópica/patología , Dinitroclorobenceno , Modelos Animales de Enfermedad , Inmunoglobulina E/sangre , Proteínas de Insectos/aislamiento & purificación , Mastocitos/efectos de los fármacos , Mastocitos/inmunología , Mastocitos/metabolismo , Ratones , Ratones Endogámicos BALB C , Fosfolipasas A2/aislamiento & purificación , Piel/efectos de los fármacos , Piel/inmunología , Piel/metabolismo , Piel/patología , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Células TH1/efectos de los fármacos , Células TH1/inmunología , Células TH1/metabolismo , Células Th2/efectos de los fármacos , Células Th2/inmunología , Células Th2/metabolismo , Factores de Tiempo

RESUMEN

Asthma is a common chronic disease characterized by bronchial inflammation, reversible airway obstruction, and airway hyperresponsiveness (AHR). Current therapeutic options for the management of asthma include inhaled corticosteroids and ß2 agonists, which elicit harmful side effects. In the present study, we examined the capacity of phospholipase A2 (PLA2), one of the major components of bee venom (BV), to reduce airway inflammation and improve lung function in an experimental model of asthma. Allergic asthma was induced in female BALB/c mice by intraperitoneal administration of ovalbumin (OVA) on days 0 and 14, followed by intratracheal challenge with 1% OVA six times between days 22 and 30. The infiltration of immune cells, such as Th2 cytokines in the lungs, and the lung histology, were assessed in the OVA-challenged mice in the presence and absence of an intratracheal administration of bvPLA2. We showed that the intratracheal administration of bvPLA2 markedly suppressed the OVA-induced allergic airway inflammation by reducing AHR, overall area of inflammation, and goblet cell hyperplasia. Furthermore, the suppression was associated with a significant decrease in the production of Th2 cytokines, such as IL-4, IL-5, and IL-13, and a reduction in the number of total cells, including eosinophils, macrophages, and neutrophils in the airway.

Asunto(s)

Antiasmáticos/uso terapéutico , Asma/tratamiento farmacológico , Venenos de Abeja/enzimología , Fosfolipasas A2/uso terapéutico , Alérgenos , Animales , Antiasmáticos/administración & dosificación , Antiasmáticos/farmacología , Asma/inmunología , Asma/patología , Asma/fisiopatología , Líquido del Lavado Bronquioalveolar/citología , Recuento de Células , Citocinas/inmunología , Femenino , Inmunoglobulina E/sangre , Leucotrieno B4/inmunología , Pulmón/efectos de los fármacos , Pulmón/inmunología , Pulmón/patología , Ratones , Ratones Endogámicos BALB C , Ovalbúmina , Fosfolipasas A2/administración & dosificación , Fosfolipasas A2/farmacología

RESUMEN

Bee venom (BV) is one of the alternative medicines that have been widely used in the treatment of chronic inflammatory diseases. We previously demonstrated that BV induces immune tolerance by increasing the population of regulatory T cells (Tregs) in immune disorders. However, the major component and how it regulates the immune response have not been elucidated. We investigated whether bee venom phospholipase A2 (bvPLA2) exerts protective effects that are mediated via Tregs in OVA-induced asthma model. bvPLA2 was administered by intraperitoneal injection into control and OVA-challenged mice. The Treg population, total and differential bronchoalveolar lavage fluid (BALF) cell count, Th2 cytokines, and lung histological features were assessed. Treg depletion was used to determine the involvement of Treg migration and the reduction of asthmatic symptoms. The CD206-dependence of bvPLA2-treated suppression of airway inflammation was evaluated in OVA-challenged CD206(-/-) mice. The bvPLA2 treatment induced the Tregs and reduced the infiltration of inflammatory cells into the lung in the OVA-challenged mice. Th2 cytokines in the bronchoalveolar lavage fluid (BALF) were reduced in bvPLA2-treated mice. Although bvPLA2 suppressed the number of inflammatory cells after OVA challenge, these effects were not observed in Treg-depleted mice. In addition, we investigated the involvement of CD206 in bvPLA2-mediated immune tolerance in OVA-induced asthma model. We observed a significant reduction in the levels of Th2 cytokines and inflammatory cells in the BALF of bvPLA2-treated OVA-induced mice but not in bvPLA2-treated OVA-induced CD206(-/-) mice. These results demonstrated that bvPLA2 can mitigate airway inflammation by the induction of Tregs in an OVA-induced asthma model.