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1.
Toxins (Basel) ; 16(2)2024 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-38393162

RESUMO

Limited evidence suggests that stimulating adipose-derived stem cells (ASCs) indirectly promotes hair growth. We examined whether bee venom (BV) activated ASCs and whether BV-induced hair growth was facilitated by enhanced growth factor release by ASCs. The induction of the telogen-to-anagen phase was studied in mice. The underlying mechanism was investigated using organ cultures of mouse vibrissa hair follicles. When BV-treated ASCs were injected subcutaneously into mice, the telogen-to-anagen transition was accelerated and, by day 14, the hair weight increased. Quantitative polymerase chain reaction (qPCR) revealed that BV influenced the expression of several molecules, including growth factors, chemokines, channels, transcription factors, and enzymes. Western blot analysis was employed to verify the protein expression levels of extracellular-signal-regulated kinase (ERK) and phospho-ERK. Both the Boyden chamber experiment and scratch assay confirmed the upregulation of cell migration by BV. Additionally, ASCs secreted higher levels of growth factors after exposure to BV. Following BV therapy, the gene expression levels of alkaline phosphatase (ALP), fibroblast growth factor (FGF)-1 and 6, endothelial cell growth factor, and platelet-derived growth factor (PDGF)-C were upregulated. The findings of this study suggest that bee venom can potentially be utilized as an ASC-preconditioning agent for hair regeneration.


Assuntos
Venenos de Abelha , Animais , Camundongos , Venenos de Abelha/farmacologia , Venenos de Abelha/metabolismo , Proliferação de Células , Cabelo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Células-Tronco/metabolismo , Células Cultivadas
2.
Mol Biol Rep ; 51(1): 2, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057592

RESUMO

BACKGROUND: Lung cancer, one of the most common oncological diseases worldwide, continues to be the leading cause of cancer-related deaths. The development of new approaches for lung cancer, which still has a low survival rate despite medical advances, is of great importance. METHODS AND RESULTS: In this study, bee venom (BV), conditioned medium of MSCs isolated from dental follicles (MSC-CM) and cisplatin were applied at different doses and their effects on A549 cell line were evaluated. Dental follicles were used as a source of MSCs source and differentiation kits, and characterization studies (flow cytometry) were performed. Cell viability was measured by the MTT method and apoptosis was measured by an Annexin V-FITC/PI kit on flow cytometer. IC50 dose values were determined according to the 24th hour and were determined as 15.8 µg/mL for BV, 10.78% for MSC-CM and 5.77 µg/mL for cisplatin. IC50 values found for BV and MSC-CM were also given in combination and the effects were observed. It was found that the applied substances caused BV to decrease in cell viability and induced apoptosis in cells. In addition to the induction of apoptosis in BV, MSC-CM, and combined use, all three applications led to an increase in Bax protein expression and a decrease in Bcl-2 protein expression. The molecular mechanism of anticancer activity through inhibition of Bax and Bcl-2 proteins and the NF-κB signaling pathway may be suggested. CONCLUSION: Isolated MSCs in our study showed anticancer activity and BV and MSC-CM showed synergistic antiproliferative and apoptotic effects.


Assuntos
Venenos de Abelha , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Células-Tronco Mesenquimais , Humanos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Cisplatino/farmacologia , Cisplatino/metabolismo , Neoplasias Pulmonares/metabolismo , Venenos de Abelha/farmacologia , Venenos de Abelha/metabolismo , Apoptose , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Células-Tronco Mesenquimais/metabolismo
3.
Physiol Res ; 72(4): 455-463, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37795888

RESUMO

Accidents with venomous bees are a serious worldwide health concern. Since the kidney has been reported as the main venom-target organ, the present study was undertaken to investigate the in vivo nephrotoxic effect of Algerian bee venom (ABV) (Apis mellifera intermissa) collected in the middle east of Algeria. A preliminary study was performed on ABV to identify the ABV using SDS-PAGE analysis and to determine the in vivo intraperitoneal median lethal dose (LD50) using the Probit analysis test. In vivo nephrotoxic effect was assessed through the determination of physiological and kidney biochemical markers in mice intraperitoneally injected with ABV at doses of 0.76 (D1); 1.14 (D2) and 2.29 mg/kg body weight (bwt) (D3), corresponding respectively to LD50/15, LD50/10, and LD50/5 (i.p. LD50=11.48 mg/kg bwt) for seven consecutive days. Results revealed a marked decrease in body weight gain and food intake, and an increase in absolute and relative kidney weights in ABV D2 and D3 treated mice compared with controls. Furthermore, ABV D2 and D3 resulted in a significant increase in serum creatinine, urea, and uric acid. ABV-induced oxidative stress was evidenced by a significant increase in kidney MDA level, and a significant depletion in kidney GSH level, and catalase activity. Meanwhile, no marked changes in the above-mentioned parameters were noticed in ABV D1. Accordingly, the adverse nephrotoxic effect of ABV was proved by the dose-dependent kidney histological changes. In summary, the results of the present study evidence that ABV at doses of 1.14 (D2) and 2.28 mg/kg body weight (bwt) can cause marked changes in kidney biochemical and major antioxidant markers, and histological architecture.


Assuntos
Venenos de Abelha , Camundongos , Animais , Venenos de Abelha/toxicidade , Venenos de Abelha/metabolismo , Rim , Estresse Oxidativo , Antioxidantes/farmacologia , Peso Corporal
4.
Artigo em Inglês | MEDLINE | ID: mdl-37196854

RESUMO

In this study, the biochemical and physiological features of the firebug Pyrrhocoris apterus were investigated to understand the impact of the honeybee Apis mellifera venom on them using physiological methods (mortality, total level of metabolism), biochemical methods (ELISA, mass spectrometry, polyacrylamide gel electrophoresis, spectrophotometry) and molecular methods (real-time PCR). Together, the obtained findings suggest that venom injection increased the level of adipokinetic hormone (AKH) in the CNS of P. apterus, indicating that this hormone plays a key role in activating defence responses. Furthermore, histamine levels in the gut increased significantly after envenomation and did not seem to be modulated by AKH. In contrast, histamine levels in the haemolymph increased after treatment with AKH and AKH + venom. In addition, we found that vitellogenin levels in haemolymph decreased in both males and females after venom application. Lipids, which are the main energy metabolites used by Pyrrhocoris, were significantly exhausted from the haemolymph after the administration of venom and the co-application with AKH reversed this effect. However, we did not find much influence on the effect of digestive enzymes after the injection of venom. Our research has highlighted the noticeable effect of bee venom on P. apterus' body and provided new insights into the role of AKH in controlling defensive responses. However, it is also likely that there will be alternative defence mechanisms.


Assuntos
Venenos de Abelha , Heterópteros , Hormônios de Inseto , Feminino , Masculino , Animais , Venenos de Abelha/metabolismo , Histamina/farmacologia , Heterópteros/metabolismo , Hormônios de Inseto/farmacologia , Ácido Pirrolidonocarboxílico/metabolismo
5.
Dev Comp Immunol ; 135: 104478, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35716829

RESUMO

In bee venoms, low-molecular-weight peptides, including serine protease inhibitors (SPIs), exhibit multifunctional activities. Although SPIs in bee venoms are relatively well known, those that function in both the body and secreted venom of bees are not well-characterized. In this study, we identified a bumblebee (Bombus ignitus) SPI (BiSPI) that displays microbicidal and anti-fibrinolytic activities. BiSPI was found to consist of a trypsin inhibitor-like domain containing a P1 site and ten cysteine residues. We observed that the BiSPI gene was ubiquitously transcribed in the body, including the venom glands. In correlation, the BiSPI protein was detected both in the body and secreted venom by using an antibody against a recombinant BiSPI peptide produced in baculovirus-infected insect cells. Recombinant BiSPI exhibited inhibitory activity against trypsin but not chymotrypsin and inhibited microbial serine proteases and plasmin but not elastase or thrombin. Moreover, recombinant BiSPI recognized carbohydrates and bound to fungi and gram-negative and gram-positive bacteria. Consistent with these properties, recombinant BiSPI exhibited microbicidal activities against bacteria and fungi through induction of structural damage by binding to the microbial surfaces. Additionally, recombinant BiSPI inhibited the plasmin-mediated degradation of human fibrin and was thus concluded to exhibit anti-fibrinolytic activity. Moreover, the peptide showed no effect on hemolysis. These findings demonstrate the dual function of BiSPI, which acts as a microbicidal peptide and anti-fibrinolytic venom toxin.


Assuntos
Anti-Infecciosos , Venenos de Abelha , Serpinas , Animais , Anti-Infecciosos/metabolismo , Antivenenos/genética , Venenos de Abelha/metabolismo , Abelhas/genética , Clonagem Molecular , Fibrinolisina , Fungos , Humanos , Elastase Pancreática , Peptídeos/genética , Proteínas Recombinantes/genética , Inibidores de Serina Proteinase/genética , Serpinas/genética
6.
Artigo em Inglês | MEDLINE | ID: mdl-34775045

RESUMO

Worker honey bees are subject to biochemical and physiological changes throughout the year. This study aimed to provide the reasons behind these fluctuations. The markers analysed included lipid, carbohydrate, and protein levels in the haemolymph; the activity of digestive enzymes in the midgut; the levels of adipokinetic hormone (AKH) in the bee central nervous system; the levels of vitellogenins in the bee venom and haemolymph; and the levels of melittin in the venom. The levels of all the main nutrients in the haemolymph peaked mostly within the period of maximal bee activity, whereas the activity of digestive enzymes mostly showed a two-peak course. Furthermore, the levels of AKHs fluctuated throughout the year, with modest but significant variations. These data suggest that the role of AKHs in bee energy metabolism is somewhat limited, and that bees rely more on available food and less on body deposits. Interestingly, the non-metabolic characteristics also fluctuated over the year. The vitellogenin peak reached its maximum in the haemolymph in winter, which is probably associated with the immunoprotection of long-lived winter bees. The analysis of bee venom showed the maximal levels of vitellogenin in autumn; however, it is not entirely clear why this is the case. Finally, melittin levels showed strong fluctuations, suggesting that seasonal control was unlikely.


Assuntos
Abelhas/fisiologia , Estações do Ano , Animais , Venenos de Abelha/metabolismo , Biomarcadores/metabolismo , Sistema Nervoso Central/metabolismo , Sistema Digestório/enzimologia , Hemolinfa/metabolismo , Hormônios de Inseto/metabolismo , Meliteno/metabolismo , Oligopeptídeos/metabolismo , Ácido Pirrolidonocarboxílico/análogos & derivados , Ácido Pirrolidonocarboxílico/metabolismo , Vitelogeninas/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-34826612

RESUMO

To explore and compare the expression patterns of venom components depending on post-capture periods, venom gland-specific transcriptome and proteome analyses were conducted for five model hymenopteran species at a series of time points after capture. Venom gland-specific genes with signal sequences were considered as putative venom component genes. Expression patterns of venom gland-specific genes in all the social wasps and bees examined varied considerably depending on the post-capture period. Higher numbers of venom genes exhibited a decreasing expression pattern than an increasing pattern as the capture period increased. For example, genes encoding most of the allergens (dipeptidyl peptidase 4, endocuticle structural glycoprotein, odorant-binding protein, phospholipase A1, A2, B1, serine protease, serine protease inhibitor and venom allergen 5), pain-producing factor (mast cell degranulating peptide), and paralyzing factor (neprilysin) commonly exhibited decreasing expression patterns in all of the hymenopteran species tested, except for some of the major venom genes in Apis mellifera and Bombus ignitus, which showed an increasing pattern. These findings indicate species- or group-specific variations in the expression patterns of major venom genes. Taken together, flash freezing in liquid nitrogen immediately after capture was determined to be the best way to obtain the most natural expression profiles of venom components in social wasp species, thus, enabling a better understanding of the toxic potential of venom in wasp sting accidents. This study provides guidance for establishing optimal protocols for venom gland isolation and venom extraction from wasps and bees that can ensure the most naturally represented venom composition.


Assuntos
Venenos de Abelha/genética , Abelhas , Proteínas de Insetos/genética , Venenos de Vespas/genética , Vespas , Animais , Venenos de Abelha/metabolismo , Abelhas/genética , Abelhas/fisiologia , Glândulas Exócrinas/fisiologia , Feminino , Regulação da Expressão Gênica , Proteínas de Insetos/metabolismo , Comportamento Social , Estresse Fisiológico , Fatores de Tempo , Venenos de Vespas/metabolismo , Vespas/genética , Vespas/fisiologia
8.
Int J Mol Sci ; 22(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34445319

RESUMO

Anticancer peptides (ACPs) could potentially offer many advantages over other cancer therapies. ACPs often target cell membranes, where their surface mechanism is coupled to a conformational change into helical structures. However, details on their binding are still unclear, which would be crucial to reach progress in connecting structural aspects to ACP action and to therapeutic developments. Here we investigated natural helical ACPs, Lasioglossin LL-III, Macropin 1, Temporin-La, FK-16, and LL-37, on model liposomes, and also on extracellular vesicles (EVs), with an outer leaflet composition similar to cancer cells. The combined simulations and experiments identified three distinct binding modes to the membranes. Firstly, a highly helical structure, lying mainly on the membrane surface; secondly, a similar, yet only partially helical structure with disordered regions; and thirdly, a helical monomeric form with a non-inserted perpendicular orientation relative to the membrane surface. The latter allows large swings of the helix while the N-terminal is anchored to the headgroup region. These results indicate that subtle differences in sequence and charge can result in altered binding modes. The first two modes could be part of the well-known carpet model mechanism, whereas the newly identified third mode could be an intermediate state, existing prior to membrane insertion.


Assuntos
Peptídeos Catiônicos Antimicrobianos/química , Antineoplásicos/química , Venenos de Abelha/química , Membrana Celular/metabolismo , Motivos de Aminoácidos , Peptídeos Catiônicos Antimicrobianos/metabolismo , Antineoplásicos/metabolismo , Venenos de Abelha/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , Ligação Proteica , Domínios Proteicos , Catelicidinas
9.
J Anim Physiol Anim Nutr (Berl) ; 105(5): 975-983, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33856075

RESUMO

The aim of the present study was to investigate the long-term effect of using bee venom (BV) on the reproductive performance, immune, and health status of rabbit does and its effect on their litters. Sixty mature does, from Spanish V-line rabbit stock, were randomly assigned to four homogeneous groups with 15 does each. The 1st , 2nd and 3rd groups were injected twice weekly under the neck skin with 0.1 ml solution contains 0.1, 0.2 and 0.3 mg BV/rabbit respectively. The 4th group served as a control group. From the results, litter size at birth, litter weight and survival rate at weaning age as well as milk yield were significantly (p ≤ 0.05) increased in BV groups than in the control group. Serum estradiol 17-ß (E2) was significantly (p ≤ 0.05) higher (15%) in the rabbit does treated with BV compared to the control group. The treated does with BV at any study doses showed a gradual and significant (p ≤ 0.05) decrease (12%) in serum progesterone levels (P4) compared to the control. They also showed a significant (p≤0.05) increase in conception (17%) and fertility rates (10%) compared to the control does. Treatment of rabbit does with BV caused a gradual and significant (p ≤ 0.05) reduction in both aspartate aminotransferase (AST) (16%) and alanine aminotransferase (ALT) (37%) liver enzyme activities. Additionally, results have shown that BV resulted in a gradual and significant (p ≤ 0.05) increase in total antioxidant capacity (TAC), antioxidative enzymes such as glutathione S-transferase (GST) and glutathione peroxidase (GPx), serum IgG, IgM and IgA levels with significant (p ≤ 0.05) decrease in malondialdehyde (MDA) and thiobarbituric acid reactive substances (TBARS) in BV groups compared to the control group. Results suggest that BV can be used in rabbit farming as an effective and safe alternative to artificial chemical drugs (sexual-stimulants) to improve certain reproductive traits, immune response and health.


Assuntos
Venenos de Abelha , Animais , Antioxidantes/metabolismo , Venenos de Abelha/metabolismo , Feminino , Nível de Saúde , Peroxidação de Lipídeos , Fígado/metabolismo , Estresse Oxidativo , Coelhos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
10.
Mol Immunol ; 135: 183-190, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33930713

RESUMO

Bee venom is a complex mixture of molecules, among which melittin and phospholipase A2 (PLA2) are the toxic components involved in envenoming accidents with multiple honeybee stings. Traditionally, the treatment of envenomings has been based on the administration of specific antibodies to neutralize the deleterious effects of toxins. An alternative to mammalian polyclonal antibodies is the use of egg yolk immunoglobulins (IgY) due to their advantages regarding animal welfare and lower costs of production as compared to the conventional production methods. In this work, a novel composition containing specific IgY antibodies was developed. After four immunizations, IgY extracted from the egg yolks was able to recognize several components of the bee venom, including melittin and PLA2. The performance of IgY to neutralize the lethal activity was evaluated in a mouse model by using one median lethal dose (LD50) of the bee venom. The effective dose of the IgY extract was determined as 30.66 µg/mg. These results demonstrate the feasibility to produce IgY-based antivenoms to treat envenomings by multiple bee stings.


Assuntos
Anticorpos Neutralizantes/imunologia , Venenos de Abelha/antagonistas & inibidores , Venenos de Abelha/imunologia , Imunoglobulinas/imunologia , Imunoglobulinas/farmacologia , Mordeduras e Picadas de Insetos/terapia , Animais , Venenos de Abelha/metabolismo , Abelhas/patogenicidade , Embrião de Galinha , Galinhas , Gema de Ovo/imunologia , Feminino , Masculino , Meliteno/imunologia , Camundongos , Fosfolipases A2/imunologia
11.
Sci Rep ; 10(1): 21645, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33303913

RESUMO

Honeybee (Apis mellifera) venom (HBV) has been a subject of extensive proteomics research; however, scarce information on its metabolite composition can be found in the literature. The aim of the study was to identify and quantify the metabolites present in HBV. To gain the highest metabolite coverage, three different mass spectrometry (MS)-based methodologies were applied. In the first step, untargeted metabolomics was used, which employed high-resolution, accurate-mass Orbitrap MS. It allowed obtaining a broad overview of HBV metabolic components. Then, two targeted metabolomics approaches, which employed triple quadrupole MS, were applied to quantify metabolites in HBV samples. The untargeted metabolomics not only confirmed the presence of amines, amino acids, carbohydrates, and organic acids in HBV, but also provided information on venom components from other metabolite classes (e.g., nucleosides, alcohols, purine and pyrimidine derivatives). The combination of three MS-based metabolomics platforms facilitated the identification of 214 metabolites in HBV samples, among which 138 were quantified. The obtaining of the wide free amino acid profiles of HBV is one of the project's achievements. Our study contributed significantly to broadening the knowledge about HBV composition and should be continued to obtain the most comprehensive metabolite profile of HBV.


Assuntos
Venenos de Abelha/química , Abelhas/metabolismo , Metabolômica , Aminoácidos/análise , Animais , Venenos de Abelha/análise , Venenos de Abelha/metabolismo , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Espectrometria de Massas , Peso Molecular
12.
Toxins (Basel) ; 12(7)2020 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-32664544

RESUMO

Bee venom (BV) is a rich source of secondary metabolites from honeybees (Apis mellifera L.). It contains a variety of bioactive ingredients including peptides, proteins, enzymes, and volatile metabolites. The compounds contribute to the venom's observed biological functions as per its anti-inflammatory and anticancer effects. The antimicrobial action of BV has been shown in vitro and in vivo experiments against bacteria, viruses, and fungi. The synergistic therapeutic interactions of BV with antibiotics has been reported. The synergistic effect contributes to a decrease in the loading and maintenance dosage, a decrease in the side effects of chemotherapy, and a decrease in drug resistance. To our knowledge, there have been no reviews on the impact of BV and its antimicrobial constituents thus far. The purpose of this review is to address the antimicrobial properties of BV and its compounds.


Assuntos
Anti-Infecciosos/uso terapêutico , Venenos de Abelha/uso terapêutico , Abelhas/metabolismo , Animais , Antibacterianos/uso terapêutico , Antifúngicos/uso terapêutico , Antivirais/uso terapêutico , Venenos de Abelha/metabolismo , Humanos , Metabolismo Secundário
14.
BMB Rep ; 53(8): 419-424, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32317085

RESUMO

Bee venom (BV), secreted from the venom gland of the honey bee, contains several biological active compounds. BV has been widely used as a traditional medicine for treating human disease, including cancer. In this study, we have shown the molecular mechanism underlying the therapeutic effect of BV on cancer. Treatment with BV reduced the proliferation of cervical-cancer cells in a dose- and time-dependent manner. Interestingly, the killing effect of BV was specific to HPVpositive cervical-cancer cell lines, such as Caski and HeLa cells, and not to HPV-negative cervical-cancer cells (C33A). BV reduced the expression of HPV E6 and E7 at RNA and protein levels, leading to an increase in the expression of p53 and Rb in Caski and HeLa cells. Further, BV decreased the levels of cell-cycle proteins, such as cyclin A and B, and increased the levels of cell-cycle inhibitors, such as p21 and p27. BV significantly induced apoptosis and inhibited wound healing and migration of cervical-cancer cells. It also upregulated the expression of pro-apoptotic BAX and downregulated the expression of anti-apoptotic Bcl-2 and Bcl-XL. Cleavage of caspase-3, caspase-9, and PARP were also induced by BV treatment, whereas the phosphorylation of mitogenic signalingrelated proteins, such as AKT, JNK, p38, and ERK, were downregulated. Our results indicate that BV has a therapeutic selectivity for HPV-positive malignant cells, so further clinical studies are needed to assess its clinical application. [BMB Reports 2020; 53(8): 419-424].


Assuntos
Venenos de Abelha/farmacologia , Neoplasias do Colo do Útero/tratamento farmacológico , Apoptose/efeitos dos fármacos , Venenos de Abelha/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Células HeLa , Humanos , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/tratamento farmacológico , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Transdução de Sinais/efeitos dos fármacos , Neoplasias do Colo do Útero/metabolismo
15.
Biochemistry ; 59(7): 836-850, 2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-31990535

RESUMO

Tertiapin (TPN) is a 21 amino acid venom peptide from Apis mellifera that inhibits certain members of the inward rectifier potassium (Kir) channel family at a nanomolar affinity with limited specificity. Structure-based computational simulations predict that TPN behaves as a pore blocker; however, the molecular determinants mediating block of neuronal Kir3 channels have been inconclusive and unvalidated. Here, using molecular docking and molecular dynamics (MD) simulations with 'potential of mean force' (PMF) calculations, we investigated the energetically most favored interaction of TPN with several Kir3.x channel structures. The resulting binding model for Kir3.2-TPN complexes was then tested by targeted mutagenesis of the predicted contact sites, and their impact on the functional channel block was measured electrophysiologically. Together, our findings indicate that a high-affinity TPN block of Kir3.2 channels involves a pore-inserting lysine side chain requiring (1) hydrophobic interactions at a phenylalanine ring surrounding the channel pore and (2) electrostatic interactions with two adjacent Kir3.2 turret regions. Together, these interactions collectively stabilize high-affinity toxin binding to the Kir3.2 outer vestibule, which orients the ε-amino group of TPN-K21 to occupy the outermost K+ binding site of the selectivity filter. The structural determinants for the TPN block described here also revealed a favored subunit arrangement for assembled Kir3.x heteromeric channels, in addition to a multimodal binding capacity of TPN variants consistent with the functional dyad model for polybasic peptide pore blockers. These novel findings will aid efforts in re-engineering the TPN pharmacophore to develop peptide variants having unique and distinct Kir channel blocking properties.


Assuntos
Venenos de Abelha/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/metabolismo , Sequência de Aminoácidos , Animais , Venenos de Abelha/química , Abelhas/química , Sítios de Ligação , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/química , Humanos , Camundongos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Xenopus laevis
16.
Biochim Biophys Acta Gen Subj ; 1863(11): 129409, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31398379

RESUMO

BACKGROUND: Previous glycophylogenetic comparisons of dipteran and lepidopteran species revealed variations in the anionic and zwitterionic modifications of their N-glycans; therefore, we wished to explore whether species- and order-specific glycomic variations would extend to the hymenoptera, which include the honeybee Apis mellifera, an agriculturally- and allergologically-significant social species. METHODS: In this study, we employed an off-line liquid chromatography/mass spectrometry approach, in combination with enzymatic and chemical treatments, to analyse the N-glycans of male honeybee larvae and honeybee venom in order to facilitate definition of isomeric structures. RESULTS: The neutral larval N-glycome was dominated by oligomannosidic and paucimannosidic structures, while the neutral venom N-glycome displayed more processed hybrid and complex forms with antennal N-acetylgalactosamine, galactose and fucose residues including Lewis-like epitopes; the anionic pools from both larvae and venom contained a wide variety of glucuronylated, sulphated and phosphoethanolamine-modified N-glycans with up to three antennae. In comparison to honeybee royal jelly, there were more fucosylated and fewer Man4/5-based hybrid glycans in the larvae and venom samples as well as contrasting antennal lengths. CONCLUSIONS: Combining the current data on venom and larvae with that we previously published on royal jelly, a total honeybee N-glycomic repertoire of some 150 compositions can be proposed in addition to the 20 previously identified on specific venom glycoproteins. SIGNIFICANCE: Our data are indicative of tissue-specific modification of the core and antennal regions of N-glycans in Apis mellifera and reinforce the concept that insects are capable of extensive processing to result in rather complex anionic oligosaccharide structures.


Assuntos
Venenos de Abelha/metabolismo , Abelhas/metabolismo , Proteínas de Insetos/metabolismo , Animais , Glicosilação , Masculino , Especificidade de Órgãos
17.
Nat Commun ; 10(1): 1352, 2019 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-30902995

RESUMO

G-protein-gated inward rectifying potassium channels (GIRKs) require Gßγ subunits and phosphorylated phosphatidylinositides (PIPs) for gating. Although studies have provided insight into these interactions, the mechanism of how these events are modulated by Gßγ and the binding affinity between PIPs and GIRKs remains poorly understood. Here, native ion mobility mass spectrometry is employed to directly monitor small molecule binding events to mouse GIRK2. GIRK2 binds the toxin tertiapin Q and PIPs selectively and with significantly higher affinity than other phospholipids. A mutation in GIRK2 that causes a rotation in the cytoplasmic domain, similarly to Gßγ-binding to the wild-type channel, revealed differences in the selectivity towards PIPs. More specifically, PIP isoforms known to weakly activate GIRKs have decreased binding affinity. Taken together, our results reveal selective small molecule binding and uncover a mechanism by which rotation of the cytoplasmic domain can modulate GIRK•PIP interactions.


Assuntos
Venenos de Abelha/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/metabolismo , Mamíferos/metabolismo , Fosfatidilinositóis/metabolismo , Animais , Espectrometria de Massas , Camundongos , Mutação/genética , Fosforilação , Ligação Proteica
18.
Toxins (Basel) ; 12(1)2019 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-31905643

RESUMO

Organic acids are important active small molecules present in venoms and toxins, which have not been fully explored yet. The aim of the study was the determination of organic acids in honeybee venom (HBV) samples by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Two protocols for sample preparation were employed. A solid-phase extraction was used for the determination of malonic acid, fumaric acid, glutaric acid, and kynurenic acid. A dilute-and-shoot method was optimal for: citric acid, malic acid, and succinic acid. Chromatographic separation was performed using a Synergi Hydro-RP column. Detection was performed on a triple-quadrupole mass spectrometer operating in multiple reaction monitoring mode. Among the analytes, glutaric acid and kynurenic acid were present in HBV samples in the lowest concentrations, whereas citric acid was the most abundant acid in each sample, and accounted for an average of 86 mg/g (8.6%) of the venom dry weight. Organic acids were discussed in terms of function. This is the first study in the available literature that provides specific data on the content of organic acids in HBV using a validated quantitative method.


Assuntos
Venenos de Abelha/química , Venenos de Abelha/metabolismo , Abelhas , Ácidos/análise , Animais , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Metabolômica , Extração em Fase Sólida , Espectrometria de Massas em Tandem
19.
J Insect Sci ; 18(4)2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30060211

RESUMO

Honey bees (Apis mellifera) (Hymenoptera: Apidae) are social insects that have evolved a coordinated defensive response to ensure colony survival. Their nests may contain valuable resources such as pollen and nectar that are attractive to a range of insect and mammalian intruders and need protecting. With sufficient provocation, honey bees will mobilize and sting intruders, who are likely to incur additional stings. To inspect and manage their colonies, beekeepers apply smoke to decrease the likelihood of being stung. The use of smoke is a ubiquitous beekeeping practice, but the reasons behind its efficacy remain unknown. In this study, we examined the effects of smoke on honey bee defensive behavior by assessing individual sting extension responses under smoke conditions. We applied a brief voltage to the bee, ranging from a mild to a strong perturbation, and assessed four components of the sting extension reflex using two types of smoke. We found that smoke did not influence the probability of sting extension, but it did affect whether a venom droplet was released with the stinger. The venom droplet was more likely to be released at higher voltage levels, but this effect was significantly reduced under smoke conditions. Based on these results, we propose that the venom droplet coincides with greater agitation in individual bees; and smoke reduces the probability of its release. We speculate that the venom droplet serves to amplify the sting alarm pheromone, and smoke, in its ability to reduce droplet formation, may indicate that less alarm pheromone is released.


Assuntos
Venenos de Abelha/metabolismo , Abelhas/fisiologia , Fumaça/efeitos adversos , Animais , Criação de Abelhas , Abelhas/efeitos dos fármacos , Comportamento Animal , Mecanismos de Defesa , Feromônios/metabolismo
20.
J Immunol Res ; 2018: 5038172, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29854840

RESUMO

This work is aimed at investigating the effect of melittin on identified key genes in bladder cancer (BC) and further providing a theoretical basis for BC treatment. GSE35014 downloaded from the Gene Expression Omnibus (GEO) database was used to screen differentially expressed genes (DEGs) in BC cells and control. Results showed that a total of 389 upregulated and 169 downregulated genes were identified. Subsequently, GO analysis, KEGG pathway enrichment analysis, and PPI network analysis were employed to disclose the crucial genes and signaling pathways involved in BC. Fifteen module-related DEGs and their associated signaling pathways were obtained according to the PPI network and modular analyses. Based on the analysis of articles retrieved in the PubMed database, we found that melittin could induce apoptosis and constrain the progression of tumor cells as a result of regulating critical cancer-related signaling pathways, such as PI3K-Akt and TNF signaling pathways. Furthermore, PI3K-Akt and TNF signaling pathways were also found to be associated with module-related DEGs according to biological analyses. At last, qRT-PCR analysis demonstrated that melittin could constrain the expression of module-related DEGs (LPAR1, COL5A1, COL6A2, CXCL1, CXCL2, and CXCL3) associated with PI3K-Akt and TNF signaling pathways in BC cells. Functional assays revealed that melittin could constrain the proliferative and migrated abilities of BC cells. Conjointly, these findings provide a theoretical basis for these six genes as drug-sensitive markers of melittin in BC treatment.


Assuntos
Medicina Tradicional Chinesa , Meliteno/uso terapêutico , Neoplasias da Bexiga Urinária/genética , Venenos de Abelha/metabolismo , Quimiocina CXCL1/genética , Quimiocina CXCL1/metabolismo , Quimiocina CXCL2/genética , Quimiocina CXCL2/metabolismo , Quimiocinas CXC/genética , Quimiocinas CXC/metabolismo , Colágeno Tipo V/genética , Colágeno Tipo V/metabolismo , Colágeno Tipo VI/genética , Colágeno Tipo VI/metabolismo , Bases de Dados de Ácidos Nucleicos , Conjuntos de Dados como Assunto , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Redes Reguladoras de Genes/genética , Humanos , Meliteno/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Mapas de Interação de Proteínas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Ácidos Lisofosfatídicos/genética , Receptores de Ácidos Lisofosfatídicos/metabolismo , Transdução de Sinais , Fatores de Necrose Tumoral/metabolismo , Neoplasias da Bexiga Urinária/tratamento farmacológico
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