Transferrin-mediated iron sequestration suggests a novel therapeutic strategy for controlling Nosema disease in the honey bee, Apis mellifera

Nosemosis C, a Nosema disease caused by microsporidia parasite Nosema ceranae, is a significant disease burden of the European honey bee Apis mellifera which is one of the most economically important insect pollinators. Nevertheless, there is no effective treatment currently available for Nosema disease and the disease mechanisms underlying the pathological effects of N. ceranae infection in honey bees are poorly understood. Iron is an essential nutrient for growth and survival of hosts and pathogens alike. The iron tug-of-war between host and pathogen is a central battlefield at the host-pathogen interface which determines the outcome of an infection, however, has not been explored in honey bees. To fill the gap, we conducted a study to investigate the impact of N. ceranae infection on iron homeostasis in honey bees. The expression of transferrin, an iron binding and transporting protein that is one of the key players of iron homeostasis, in response to N. ceranae infection was analysed. Furthermore, the functional roles of transferrin in iron homeostasis and honey bee host immunity were characterized using an RNA interference (RNAi)-based method. The results showed that N. ceranae infection causes iron deficiency and upregulation of the A. mellifera transferrin (AmTsf) mRNA in honey bees, implying that higher expression of AmTsf allows N. ceranae to scavenge more iron from the host for its proliferation and survival. The suppressed expression levels of AmTsf via RNAi could lead to reduced N. ceranae transcription activity, alleviated iron loss, enhanced immunity, and improved survival of the infected bees. The intriguing multifunctionality of transferrin illustrated in this study is a significant contribution to the existing body of literature concerning iron homeostasis in insects. The uncovered functional role of transferrin on iron homeostasis, pathogen growth and honey bee’s ability to mount immune responses may hold the key for the development of novel strategies to treat or prevent diseases in honey bees.

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Toxicity Evaluation of Selected Plant Water Extracts on a Honey Bee (Apis mellifera L.) Larvae Model

Animals ◽

10.3390/ani12020178 ◽

2022 ◽

Vol 12 (2) ◽

pp. 178

Author(s):

Roksana Kruszakin ◽

Paweł Migdal

Keyword(s):

Apis Mellifera ◽

Honey Bee ◽

Honey Bees ◽

Larval Rearing ◽

Distilled Water ◽

Chelidonium Majus ◽

Freeze Dried ◽

Study Laboratory ◽

The Impact

So far, larval rearing in vitro has been an important method in the assessment of bee toxicology, particularly in pesticide risk assessment. However, natural products are increasingly used to control honey bee pathogens or to enhance bee immunity, but their effects on honey bee larvae are mostly unknown. In this study, laboratory studies were conducted to determine the effects of including selected aqueous plant infusions in the diet of honey bee (Apis mellifera L.) larvae in vitro. The toxicity of infusions from three different plant species considered to be medicinal plants was evaluated: tansy (Tanacetum vulgare L.), greater celandine (Chelidonium majus L.), and coriander (Coriandrum sativum L.). The impact of each on the survival of the larvae of honey bees was also evaluated. One-day-old larvae were fed a basal diet consisting of distilled water, sugars (glucose and fructose), yeast extract, and freeze-dried royal jelly or test diets in which distilled water was replaced by plant infusions. The proportion of the diet components was adjusted to the age of the larvae. The larvae were fed twice a day. The experiment lasted seven days. Significant statistical differences in survival rates were found between groups of larvae (exposed or not to the infusions of tansy, greater celandine, and coriander). A significant decrease (p < 0.05) in the survival rate was observed in the group with the addition of a coriander herb infusion compared to the control. These results indicate that plant extracts intended to be used in beekeeping should be tested on all development stages of honey bees.

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Prevalence and distribution of Nosema ceranae in Croatian honeybee colonies

Veterinární Medicína ◽

10.17221/2983-vetmed ◽

2010 ◽

Vol 55 (No. 9) ◽

pp. 457-462 ◽

Cited By ~ 13

Author(s):

I. Tlak Gajger ◽

O. Vugrek ◽

D. Grilec ◽

Z. Petrinec

Keyword(s):

Apis Mellifera ◽

Honey Bee ◽

Microscopic Examination ◽

Honey Bees ◽

Nosema Ceranae ◽

Negative Effects ◽

Microsporidian Parasite ◽

Nosema Species ◽

Nosema Disease ◽

Bee Colonies

Nosema disease of European honey bees afflicts bees worldwide. Nosema ceranae is a recently described microsporidian parasite of the honey bee (Apis mellifera) and its geographical distribution is not well known. The disease may have many negative effects on bee colonies and cause high losses for apiculture and consequently in agriculture. With this in mind, a total of 204 samples of dead bees from different localities in Croatia were selected and investigated for distribution, prevalence and diversity of N. ceranae infection, using light microscopic examination and multiplex PCR. Our results show that N. ceranae is the only nosema species found to infect honeybees in our geographically varied collection. The nucleotide sequences of amplicons from Nosema-infested honeybee samples were 100% identical with the N. ceranae sequence deposited in the GenBank database. N. ceranae infected bees were found in samples collected from each of 21 districts, and in all three climatic areas, i.e., mediterranean, mountain, and continental parts regions of Croatia.

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RNA Interference-Mediated Knockdown of Genes Encoding Spore Wall Proteins Confers Protection against Nosema ceranae Infection in the European Honey Bee, Apis mellifera

Microorganisms ◽

10.3390/microorganisms9030505 ◽

2021 ◽

Vol 9 (3) ◽

pp. 505

Author(s):

Nan He ◽

Yi Zhang ◽

Xin Le Duan ◽

Jiang Hong Li ◽

Wei-Fone Huang ◽

...

Keyword(s):

Apis Mellifera ◽

Rna Interference ◽

Honey Bee ◽

Honey Bees ◽

Therapeutic Potential ◽

Spore Wall ◽

Nosema Ceranae ◽

Host Responses ◽

Colony Losses ◽

Nosema Disease

Nosema ceranae (Opisthosporidia: Microsporidia) is an emergent intracellular parasite of the European honey bee (Apis mellifera) and causes serious Nosema disease which has been associated with worldwide honey bee colony losses. The only registered treatment for Nosema disease is fumagillin-b, and this has raised concerns about resistance and off-target effects. Fumagillin-B is banned from use in honey bee colonies in many countries, particularly in Europe. As a result, there is an urgent need for new and effective therapeutic options to treat Nosema disease in honey bees. An RNA interference (RNAi)-based approach can be a potent strategy for controlling diseases in honey bees. We explored the therapeutic potential of silencing the sequences of two N. ceranae encoded spore wall protein (SWP) genes by means of the RNAi-based methodology. Our study revealed that the oral ingestion of dsRNAs corresponding to SWP8 and SWP12 used separately or in combination could lead to a significant reduction in spore load, improve immunity, and extend the lifespan of N. ceranae-infected bees. The results from the work completed here enhance our understanding of honey bee host responses to microsporidia infection and highlight that RNAi-based therapeutics are a promising treatment for honey bee diseases.

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Nosema ceranae (Microspora: Nosematidae): A Sweet Surprise? Investigating the Viability and Infectivity of N. ceranae Spores Maintained in Honey and on Beeswax

Journal of Economic Entomology ◽

10.1093/jee/toaa170 ◽

2020 ◽

Vol 113 (5) ◽

pp. 2069-2078

Author(s):

Courtney I MacInnis ◽

B Andrew Keddie ◽

Stephen F Pernal

Keyword(s):

Apis Mellifera ◽

Honey Bee ◽

Honey Bees ◽

Nosema Apis ◽

Current Management ◽

Modes Of Transmission ◽

Management Recommendations ◽

Nosema Disease ◽

Bee Colonies ◽

Over Time

Abstract Nosema disease is a prominent malady among adult honey bees [Apis mellifera L. (Hymenoptera: Apidae)], caused by the microsporidian parasites, Nosema apis Zander (Microspora: Nosematidae) and N. ceranae Fries et al. 1996. The biology of N. apis is well understood, as this parasite was first described over a century ago. As N. ceranae is an emerging parasite of the honey bee, we do not yet understand how long spores of this parasite survive in honey bee colonies, or all the potential modes of transmission among bees. We investigated the viability and infectivity of N. ceranae spores in honey and on beeswax over time after exposure to 33, 20, −12, and −20°C. Spores in honey maintained viability at freezing temperatures for up to 1 yr and remained viable considerably longer than those on beeswax. Based on this evidence, honey may act as an important reservoir for infective spores to initiate or perpetuate N. ceranae infections in honey bee colonies. This work provides information that may help enhance current management recommendations for apiculturalists.

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Impact of entomopathogenic nematodes on Africanized honey bees Apis mellifera L. (Hymenoptera: Apidae) workers

Semina Ciências Agrárias ◽

10.5433/1679-0359.2020v41n6supl2p3441 ◽

2020 ◽

Vol 41 (6supl2) ◽

pp. 3441-3448

Author(s):

Gabriela Libardoni ◽

◽

Raiza Abati ◽

Amanda Roberta Sampaio ◽

Fernanda Caroline Colombo ◽

...

Keyword(s):

Apis Mellifera ◽

Honey Bee ◽

Honey Bees ◽

Entomopathogenic Nematodes ◽

Steinernema Feltiae ◽

Biological Control Agents ◽

Africanized Honey Bees ◽

Africanized Honey Bee ◽

Pollinating Insects ◽

The Impact

Africanized honey bee populations (Apis mellifera L.) have been decreasing mainly due to the intense use of synthetic insecticides associated with pollution and climate change. To minimize these impacts on the environment and bee populations, the use of biological control agents has been intensified. These products are generally safer for non-target insects, such as bees, which are important pollinating insects. Thus, the objective of this study was to evaluate the impact of entomopathogenic nematodes on the longevity of the Africanized honey bee A. mellifera workers. Seven treatments were used: Heterorhabditis amazonensis, Heterorhabditis bacteriophora, Heterorhabditis indica, Steinernema carpocapsae, Steinernema feltiae, and Steinernema rarum, at a concentration of 40 infective juveniles per cm2 (IJs/cm²), and a control in which autoclaved distilled water was used. Two bioassays were performed: 1) spraying nematodes on the workers and 2) spraying nematodes on glass plates, in which the bees remained for two hours. Each treatment consisted of five replicates with 20 bees each. Bees were kept in cages of PVC (20 × 10 cm) covered with a voile fabric and provided pieces of cotton soaked in water and Candy paste. The cages were kept in a climatized room (27 ± 2 °C temperature, 60 ± 10% relative humidity, and 12 h photophase) and the mortality was evaluated from 12 to 240 hours. In bioassay 1, the three treatments with nematodes of the genus Steinernema reduced the longevity of the workers (103.9, 96.3, and 99.6 h) when compared to treatments with Heterorhabditis (149.7, 126.8, and 134.7 h), of which, only H. amazonensis (149.7 h) did not differ from the control (166.0 h). In bioassay 2, all treatments reduced the longevity of honey bees (155.4 to 93.9 h) in relation to the control (176.1 h). Entomopathogenic nematodes, especially Heterorhabditis, need to be tested using other methodologies and for different durations of exposure and application because in the laboratory, they were less selective to A. mellifera.

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Review on Sublethal Effects of Environmental Contaminants in Honey Bees (Apis mellifera), Knowledge Gaps and Future Perspectives

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18041863 ◽

2021 ◽

Vol 18 (4) ◽

pp. 1863 ◽

Cited By ~ 2

Author(s):

Agata Di Noi ◽

Silvia Casini ◽

Tommaso Campani ◽

Giampiero Cai ◽

Ilaria Caliani

Keyword(s):

Apis Mellifera ◽

Honey Bees ◽

Sublethal Effects ◽

Integrated Approach ◽

Anthropogenic Contamination ◽

Knowledge Gaps ◽

Pollination Services ◽

General Decline ◽

Polycyclic Aromatic ◽

The Impact

Honey bees and the pollination services they provide are fundamental for agriculture and biodiversity. Agrochemical products and other classes of contaminants, such as trace elements and polycyclic aromatic hydrocarbons, contribute to the general decline of bees’ populations. For this reason, effects, and particularly sublethal effects of contaminants need to be investigated. We conducted a review of the existing literature regarding the type of effects evaluated in Apis mellifera, collecting information about regions, methodological approaches, the type of contaminants, and honey bees’ life stages. Europe and North America are the regions in which A. mellifera biological responses were mostly studied and the most investigated compounds are insecticides. A. mellifera was studied more in the laboratory than in field conditions. Through the observation of the different responses examined, we found that there were several knowledge gaps that should be addressed, particularly within enzymatic and molecular responses, such as those regarding the immune system and genotoxicity. The importance of developing an integrated approach that combines responses at different levels, from molecular to organism and population, needs to be highlighted in order to evaluate the impact of anthropogenic contamination on this pollinator species.

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Survey of feral honey bee (Apis mellifera) colonies for Nosema apis in Western Australia

Australian Journal of Experimental Agriculture ◽

10.1071/ea04222 ◽

2007 ◽

Vol 47 (7) ◽

pp. 883 ◽

Cited By ~ 7

Author(s):

Rob Manning ◽

Kate Lancaster ◽

April Rutkay ◽

Linda Eaton

Keyword(s):

Apis Mellifera ◽

Honey Bee ◽

Western Australia ◽

Honey Bees ◽

Nosema Apis ◽

The South ◽

South West ◽

Feral Populations ◽

Significant Difference

The parasite, Nosema apis, was found to be widespread among feral populations of honey bees (Apis mellifera) in the south-west of Western Australia. The location, month of collection and whether the feral colony was enclosed in an object or exposed to the environment, all affected the presence and severity of infection. There was no significant difference in the probability of infection between managed and feral bees. However, when infected by N. apis, managed bees appeared to have a greater severity of the infection.

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Exploring Two Honey Bee Traits for Improving Resistance Against Varroa destructor: Development and Genetic Evaluation

Insects ◽

10.3390/insects12030216 ◽

2021 ◽

Vol 12 (3) ◽

pp. 216

Author(s):

Matthieu Guichard ◽

Benoît Droz ◽

Evert W. Brascamp ◽

Adrien von Virag ◽

Markus Neuditschko ◽

...

Keyword(s):

Apis Mellifera ◽

Honey Bee ◽

Honey Bees ◽

Varroa Destructor ◽

Field Trial ◽

Genetic Evaluation ◽

Phenotypic Correlation ◽

Apis Mellifera Mellifera ◽

Novel Traits ◽

Resistance Traits

For the development of novel selection traits in honey bees, applicability under field conditions is crucial. We thus evaluated two novel traits intended to provide resistance against the ectoparasitic mite Varroa destructor and to allow for their straightforward implementation in honey bee selection. These traits are new field estimates of already-described colony traits: brood recapping rate (‘Recapping’) and solidness (‘Solidness’). ‘Recapping’ refers to a specific worker characteristic wherein they reseal a capped and partly opened cell containing a pupa, whilst ‘Solidness’ assesses the percentage of capped brood in a predefined area. According to the literature and beekeepers’ experiences, a higher recapping rate and higher solidness could be related to resistance to V. destructor. During a four-year field trial in Switzerland, the two resistance traits were assessed in a total of 121 colonies of Apis mellifera mellifera. We estimated the repeatability and the heritability of the two traits and determined their phenotypic correlations with commonly applied selection traits, including other putative resistance traits. Both traits showed low repeatability between different measurements within each year. ‘Recapping’ had a low heritability (h2 = 0.04 to 0.05, depending on the selected model) and a negative phenotypic correlation to non-removal of pin-killed brood (r = −0.23). The heritability of ‘Solidness’ was moderate (h2 = 0.24 to 0.25) and did not significantly correlate with resistance traits. The two traits did not show an association with V. destructor infestation levels. Further research is needed to confirm the results, as only a small number of colonies was evaluated.

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Impact of Nosema Disease and American Foulbrood on Gut Bacterial Communities of Honeybees Apis mellifera

Insects ◽

10.3390/insects12060525 ◽

2021 ◽

Vol 12 (6) ◽

pp. 525

Author(s):

Poonnawat Panjad ◽

Rujipas Yongsawas ◽

Chainarong Sinpoo ◽

Chonthicha Pakwan ◽

Phakamas Subta ◽

...

Keyword(s):

Apis Mellifera ◽

Bacterial Communities ◽

454 Pyrosequencing ◽

Gut Bacteria ◽

Nosema Ceranae ◽

Paenibacillus Larvae ◽

American Foulbrood ◽

Nosema Disease ◽

The Impact ◽

Pathogenic Infection

Honeybees, Apis mellifera, are important pollinators of many economically important crops. However, one of the reasons for their decline is pathogenic infection. Nosema disease and American foulbrood (AFB) disease are the most common bee pathogens that propagate in the gut of honeybees. This study investigated the impact of gut-propagating pathogens, including Nosema ceranae and Paenibacillus larvae, on bacterial communities in the gut of A. mellifera using 454-pyrosequencing. Pyrosequencing results showed that N. ceranae was implicated in the elimination of Serratia and the dramatic increase in Snodgrassella and Bartonella in adult bees’ guts, while bacterial communities of P. larvae-infected larvae were not affected by the infection. The results indicated that only N. ceranae had an impact on some core bacteria in the gut of A. mellifera through increasing core gut bacteria, therefore leading to the induction of dysbiosis in the bees’ gut.

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Varroa jacobsoni infestation of adult Africanized and Italian honey bees (Apis mellifera) in mixed colonies in Brazil

Genetics and Molecular Biology ◽

10.1590/s1415-47571999000300006 ◽

1999 ◽

Vol 22 (3) ◽

pp. 321-323 ◽

Cited By ~ 12

Author(s):

Geraldo Moretto ◽

Leonidas João de Mello Jr.

Keyword(s):

Apis Mellifera ◽

Honey Bee ◽

Honey Bees ◽

Mite Infestation ◽

Varroa Jacobsoni ◽

Africanized Honey Bees ◽

African Honey Bees ◽

Africanized Bees ◽

Bee Colonies ◽

Different Levels

Different levels of infestation with the mite Varroa jacobsoni have been observed in the various Apis mellifera races. In general, bees of European races are more susceptible to the mite than African honey bees and their hybrids. In Brazil honey bee colonies are not treated against the mite, though apparently both climate and bee race influence the mite infestation. Six mixed colonies were made with Italian and Africanized honey bees. The percentage infestation by this parasite was found to be significantly lower in adult Africanized (1.69 ± 0.44) than Italian bees (2.79 ± 0.65). This ratio was similar to that found in Mexico, even though the Africanized bees tested there had not been in contact with varroa, compared to more than 20 years of the coexistence in Brazil. However, mean mite infestation in Brazil on both kinds of bees was only about a third of that found in Mexico.

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