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1.
J Toxicol Environ Health B Crit Rev ; 27(2): 73-90, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38247328

RESUMO

Africanized bees have spread across the Americas since 1956 and consequently resulted in human and animal deaths attributed to massive attacks related to exposure from Argentina to the USA. In Brazil, more than 100,000 accidents were registered in the last 5 years with a total of 303 deaths. To treat such massive attacks, Brazilian researchers developed the first specific antivenom against Africanized honey bee sting exposure. This unique product, the first of its kind in the world, has been safely tested in 20 patients during a Phase 2 clinical trial. To develop the antivenom, a standardized process was undertaken to extract primary venom antigens from the Africanized bees for immunization of serum-producing horses. This process involved extracting, purifying, fractionating, characterizing, and identifying the venom (apitoxin) employing mass spectrometry to generate standardized antigen for hyperimmunization of horses using the major toxins (melittin and its isoforms and phospholipase A2). The current guide describes standardization of the entire production chain of venom antigens in compliance with good manufacturing practices (GMP) required by regulatory agencies. Emphasis is placed upon the welfare of bees and horses during this process, as well as the development of a new biopharmaceutical to ultimately save lives.


Assuntos
Venenos de Abelha , Mordeduras e Picadas de Insetos , Abelhas , Humanos , Animais , Antivenenos/uso terapêutico , Mordeduras e Picadas de Insetos/tratamento farmacológico , Venenos de Abelha/análise , Venenos de Abelha/química , Meliteno/análise , Meliteno/química , Fosfolipases A2 , Antígenos
2.
Biol Trace Elem Res ; 199(11): 4308-4318, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33398653

RESUMO

This study aimed to evaluate the quality of royal jelly produced by honeybees Apis mellifera supplemented with different concentrations of inorganic zinc (zinc sulfate monohydrate-0, 25, 50, and 75 ppm). Two-dimensional electrophoresis for the fractionation of royal jelly proteins was performed, and the zinc level was quantified by the flame atomic absorption spectrometry (FAAS) technique. Proteins were identified by electrospray ionization mass spectrometry (ESI MS MS). Analysis of variance followed by the Tukey test (P < 0.05) was used. Supplementation with the mineral zinc positively affected the quantification of proteins for treatments 50 and 75 ppm. However, all treatments independent of zinc concentrations showed fewer protein spots when compared to the control. All zinc-containing proteins were classified as major royal jelly proteins (MRJPs). The exposure of nursing bees to the mineral zinc in its inorganic form reduced the expression of six different MRJPs involved in larval and glands development of nursing bees (MRJP1, MRJP2, MRJP3, MRJP5, and MRJP7), however promoted an increase in the expression of royal jelly proteins involved in defense systems (MRJP8 and MRJP9). The results demonstrate that vital proteins and metabolic processes are impaired in nursing bees exposed to the mineral zinc in its inorganic form in all doses used affecting nutrition and maintenance of colonies.


Assuntos
Proteínas de Insetos , Zinco , Animais , Abelhas , Suplementos Nutricionais , Ácidos Graxos , Zinco/farmacologia
3.
Microb Pathog ; 141: 104011, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32004624

RESUMO

The antibacterial activities of apitoxin, a venom produced by Apis mellifera bee, and melittin, an antimicrobial peptide from apitoxin, were tested against planktonic and biofilm states of Staphylococcus aureus methicillin-resistant (MRSA), including clinical, and enterotoxin-producing isolates. Also, the synergism of apitoxin and melittin in combination with oxacillin were evaluated as well. The induced morphological changes on S. aureus cells of both products were detected by transmission electronic microscopy (TEM). The minimum inhibitory concentration (MIC) values were 7.2 µg/mL, and 6.7 µg/mL, for apitoxin and melittin, respectively. The minimum bactericidal concentration (MBC) values were 28.7 µg/mL, and 26 µg/mL for apitoxin and melittin, respectively. The time-kill curve assays of apitoxin or melittin with oxacillin exhibited bactericidal synergism against MRSA isolates. TEM images showed cell distortion, cell disintegration with leakage of cytoplasmic content and loss of cytoplasm content. However, apitoxin and melittin did not interfere with staphylococcal enterotoxin production or release. Thus, apitoxin and melittin are potential agents against MRSA that can serve as possible models for new antibacterial drugs.


Assuntos
Venenos de Abelha/farmacologia , Meliteno/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Abelhas/metabolismo , Biofilmes/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Testes de Sensibilidade Microbiana , Oxacilina/farmacologia , Infecções Estafilocócicas/tratamento farmacológico
4.
Biol Trace Elem Res ; 195(2): 648-657, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31473899

RESUMO

This study aimed to evaluate the quality of the royal jelly produced by Apis mellifera bees in the presence of different iron concentrations (ferrous sulfate heptahydrate-0, 25, 50, and 100 mg L-1). Two-dimensional electrophoresis was used for the fractionation of royal jelly proteins, and iron level was quantified using flame atomic absorption spectrometry technique. The proteins were identified using electrospray ionisation mass spectrometry. Analysis of variance followed by the Tukey test (P < 0.05) was utilised. Dietary supplementation with mineral Fe affected the protein content and number of proteins in the experimental period. Further, the diet containing the highest iron concentration showed a greater number of spots containing iron, as well as in the abdomen of the bees. The most protein containing Fe were classified as major royal jelly proteins. These results showed that Fe influenced the quality of royal jelly and can improve its nutritional value.


Assuntos
Ácidos Graxos/química , Compostos Ferrosos/análise , Proteínas de Insetos/análise , Animais , Abelhas , Suplementos Nutricionais , Ácidos Graxos/biossíntese , Compostos Ferrosos/administração & dosagem , Compostos Ferrosos/metabolismo , Proteínas de Insetos/metabolismo
5.
Food Chem ; 203: 252-257, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26948612

RESUMO

In this study, samples of coffee honey produced in Espírito Santo State, Brazil, were characterized based on their melissopalynology, physicochemical and nutritional properties, and mineral and caffeine contents. The caffeine content in the nectar from coffee flowers was measured by high performance liquid chromatography (HPLC). Blends of honey were obtained from three Coffea arabica crops, each with 10 colonies of Africanized Apis mellifera. All honey samples contained monofloral (75-78%) pollen belonging to C. arabica. Physicochemical parameters (total acidity, pH, moisture, dry matter, ash, and qualitative hydroxymethylfurfural) were within the approved limits established by EU legislation. Coffee honey contains high levels of ascorbic acid (294.68 mg kg(-1)) and low amounts of total flavonoids (3.51 ± 0.18 mg QE kg(-1)). The most abundant minerals were potassium and calcium (962.59 ± 154.3 and 343.75 ± 25.56 mg kg(-1), respectively). The caffeine content in coffee nectar (1.64 mg kg(-1)) was approximately 8-fold lower than that in honey (12.02 ± 0.81 mg kg(-1)).


Assuntos
Ácido Ascórbico/análise , Abelhas , Cafeína/análise , Coffea/química , Mel/análise , Animais , Abelhas/metabolismo , Brasil , Coffea/crescimento & desenvolvimento , Flavonoides/análise , Flores/química , Furaldeído/análogos & derivados , Furaldeído/análise , Pólen/química
6.
Environ Toxicol Chem ; 34(5): 1062-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25703042

RESUMO

Bees play a crucial role in pollination and generate honey and other hive products; therefore, their worldwide decline is cause for concern. New broad-spectrum systemic insecticides such as fipronil can harm bees and their use has been discussed as a potential threat to bees' survival. In the present study, the authors evaluate the in vitro toxicity of fipronil and note behavioral and motor activity changes in Africanized adult Apis mellifera that ingest or come into contact with lethal or sublethal doses of fipronil. The effects of sublethal doses on brood viability, population growth, behavior, and the expression of the defensin 1 gene in adult bees were studied in colonies fed with contaminated sugar syrup (8 µg fipronil L(-1) ). Fipronil is highly toxic to bees triggering agitation, seizures, tremors, and paralysis. Bees that are exposed to a lethal or sublethal doses showed reduced motor activity. The number of eggs that hatched, the area occupied by worker eggs, and the number of larvae and pupae that developed were reduced, adult bees showed lethargy, and colonies were abandoned when they were exposed to sublethal doses of fipronil. No change was seen in the bees' expression of defensin 1. The authors conclude that fipronil is highly toxic to honey bees and even sublethal doses may negatively affect the development and maintenance of colonies.


Assuntos
Abelhas/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Inseticidas/toxicidade , Atividade Motora/efeitos dos fármacos , Pirazóis/toxicidade , Animais , Abelhas/crescimento & desenvolvimento , Abelhas/metabolismo , Defensinas/genética , Defensinas/metabolismo , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/metabolismo , Óvulo/crescimento & desenvolvimento , Óvulo/metabolismo , Pupa/efeitos dos fármacos , Pupa/crescimento & desenvolvimento , Pupa/metabolismo
7.
J Toxicol Environ Health A ; 73(13-14): 926-33, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20563926

RESUMO

Equine antivenom is considered the only treatment for animal-generated envenomations, but it is costly. The study aimed to produce Apis mellifera (Africanized honeybee) and Crotalus durissus terrificus (C.d.t.) antivenoms using nanostructured silica (SBA-15) as adjuvant and cobalt-60 ((60)Co)-detoxified venoms utilizing young sheep. Natural and (60)Co-irradiated venoms were employed in four different hyperimmunization protocols. Thus, 8 groups of 60- to 90-d-old sheep were hyperimmunized, enzyme-linked immunosorbent assay (ELISA) serum titers collected every 14 d were assessed clinically daily, and individual weight were measured, until d 84. Incomplete Freund's (IFA) and nanostructured silica (SBA15) adjuvants were compared. The lethal dose (LD(50)) for both venoms was determined following intraperitoneal (ip) administration to mice. High-performance liquid chromatography on reversed phase (HPLC-RP) was used also to measure the (60)Co irradiation effects on Apis venom. At the end of the study, sheep were killed in a slaughterhouse. Kidneys were histologically analyzed. LD(50) was 5.97 mg/kg Apis and 0.07 mg/kg C.d.t. for native compared to 13.44 mg/kg Apis and 0.35 mg/kg C.d.t. for irradiated venoms. HPLC revealed significant differences in chromatographic profiles between native and irradiated Apis venoms. Native venom plus IFA compared with SBA-15 showed significantly higher antibody titers for both venoms. Apis-irradiated venom plus IFA or SBA-15 displayed similar antibody titers but were significantly lower when compared with native venom plus IFA. Weight gain did not differ significantly among all groups. (60)Co irradiation decreased toxicity and maintained venom immunogenic capacity, while IFA produced higher antibody titers. SBA-15 was able to act as an adjuvant without producing adverse effects. Hyperimmunization did not affect sheep weight gain, which would considerably reduce the cost of antiserum production, as these sheep were still approved for human consumption even after being subjected to hyperimmunization.


Assuntos
Adjuvantes Imunológicos/química , Antivenenos/imunologia , Venenos de Abelha/imunologia , Venenos de Crotalídeos/imunologia , Ovinos/imunologia , Dióxido de Silício/imunologia , Animais , Venenos de Abelha/efeitos da radiação , Abelhas , Radioisótopos de Cobalto , Venenos de Crotalídeos/efeitos da radiação , Crotalus , Feminino , Imunomodulação , Masculino , Camundongos
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