Female Flies Research Articles

SOME BIOLOGICAL AND ECOLOGICAL FEATURES OF HYPODERMA LATREILLE, 1818 IN TAVUSH REGION OF ARMENIA

Background. Cattle hypodermosis is a chronic parasitic disease (entomosis) that occurs as a result of parasitizing the larvae of warble flies in the body of animals. Disease is common in more than 55 countries of the world, causing great economic damage. It is considered as a parasitic disease with a certain zoonotic potential. Purpose. To conduct research on biological and ecological features of the warble flies that determines certain epidemiological traits of the caused pathology in Tavush Region of Armenia. Materials and methods. The observations were carried out in Tavush Region, and the experiments were carried out at the Research Center for Veterinary Medicine and Veterinary Sanitary Expertise at the Armenian National Agrarian University. The warble flies marked with stain, were released at a distance of 0.5 to 1.5 km from livestock farms with subsequent search and trapping of insects, located on pastures and on the skin of animals. Generally, 275 warble flies were released. Warble fly activity was evaluated visually counting the comparative number of flying insects at the fixed point per minute at different times of the day, as well as animal anxiety state caused by warble flies was identified. Statistical processing of experimental data was performed by means of “Vassart.net” online calculator. Results. Female warble flies Hypoderma bovis flew up to 12.1 km, while female warble flies H. lineatum did it up to 8.6 km. Females of H. bovis and H. lineatum demonstrated various spatial and circadian flying activity that depends on season, and altitude above the sea level. Spring generation of warble flies is more resistant to low air temperatures compared to the summer generation. Mild and humid summers, as well as an increase in the number of animals, contribute to an increase in the population of warble flies, while high temperature and high soil moisture contribute to the mass death of warble fly pupae developing in the ground. Conclusion. The research data cited in the article, detect the presence of a wide range of biocenotic factors that determine the epidemiology of cattle hypodermosis in the Tavush region of the Republic of Armenia. Cattle hypodermosis control plan was designed based on the results of the research, as well as natural and climatic conditions of Tavush region. Pasture prevention activities and periodic treatment of the cattle with insecticides were emphasized.

Synergistic Enhancement of Motor Function by Curcumin and Piperine in Alpha-Synuclein Expressing Drosophila Models

Parkinson’s disease (PD) is a neurodegenerative disease characterized by Lewy body formation mainly phosphorylated and aggregated α-synuclein, with subsequent neurotoxicity and death of dopaminergic neurons in the basal ganglia. The neuroprotective action of curcumin and piperine has been reported. We used the GAL4/UAS bipartite system for targeted expression of α-synuclein pan-neuronal and dopamine neurons to create genetically induced PD. Hence, in this study we assessed the ameliorative effect of curcumin and piperine on α-synuclein-induced dopaminergic neuron degeneration and photoreceptor degeneration in the Drosophila melanogaster model of PD. Male Drosophila melanogaster (upstream activating sequence (UAS) linked to synuclein (SNCA) flies were crossed with virgin wild-type Can-ton-S, DDC-GAL4 or GMR-GAL4 female flies) cultured on either medium containing graded concentrations of curcumin and/or piperine (5, 10, and 50 μM) or vehicle. The parameters measured included fecundity, larval motility, negative geotaxis, and lifespan. Vehicle, curcumin, or piperine supplementation in SNCA>Cs, SNCA>DDC, or SNCA>GMR flies did not affect fecundity or larval motility, but piperine (5 μM and 10 μM but not 50 μM) supplementation reduced fecundity. SNCA>DDC flies significantly reduced climbing performance and lifespan, peaked in week 4, ameliorated by the curcumin and piperine combination. Moreover, the increased aggregation of synuclein, as evidenced in ommatidial degeneration in SNCA>GMR flies’ eyes, was attenuated by the curcumin and piperine combination. Findings from the present study further reinforced the potential benefit of curcumin and piperine in the management of PD.

Detection of Biofilm Producing Bacteria causing Co-infections with Leishmania Ulcers and their Relation with Matrix metalloproteinase-13 Enzyme

Background: Protozoan parasite causes Cutaneous Leishmaniosis (CL), dermatological disorder. Infected female phlebotomus sand flies spread these parasites. Secondary bacterial infection can worsen tissue damage and scarring. Objectives: In order to accurately ascertain the incidence of secondary bacterial infection caused biofilm formation in cutaneous leishmaniosis, it is imperative to investigate the significant immunological alterations by quantifying the levels of human Matrix metalloproteinase -13 (MMP-13). Materials and Methods: This study included 90 samples (20 controls and 70 CL sufferers). Study participants ranged in age from 3 months to 65 years, including both genders. Human Matrix metalloproteinase -13 measured by ELISA technique. Ulcer exudates were collected with sterile swabs after non-ulcerated lesions scraped. The specimens were cultured on Blood Agar, MacConkey Agar, Mannitol Salt Agar,and Hi Chrom Acinito. Laboratory methods were identified biofilm producing microorganisms. Results: Biofilms- forming secondary bacterial infections were found in 30 (42.8%) of 70 cutaneous Leishmaniosis patients. Bacterial from lesions Acinetobacter baumanni (8) cases (26.6 %), Acinetobacter lwoffi, Crobactor, Klebsiella, Proteus mirabilis, Proteus vulgaris, Pseudomonas Luteola, Raoultella, Serratia, Sphingo, (1) cases (3.3 %) for each spp. Pantoea (2) cases (6.6 %), Pseudomonas fluorescence (3) cases (10 %), and the study found no differences in MMP-13 levels in CL patients (5.7 + 0.2) compared to the control group. Conclusions: This study observed no differences in the average concentration in level of MMP-13 patient with CL compared with control groups.

Are phlebotomine sand flies (Diptera: Psychodidae) really attracted to UV-light sources?

Phlebotomine sand flies are the sole confirmed vector of leishmaniosis, a group of endemic and re-emerging diseases in southern European countries such as Spain. Light traps are the major surveillance method currently being employed. Nevertheless, color light attraction by sand flies remains mostly unknown. Following prior research, the effect of UV-LED light sources, and its synergic effect with different color lights has been evaluated employing a modified Flebocollect (FC) light trap model. Results suggest that female Phlebotomus perniciosus sand flies are more attracted to a FC trap lured with the combination of blue and UV LED light sources than commercial CDC (Center for Disease Control and prevention) traps (Bonferroni post-hoc test; p < 0.08; blue/UV mean = 0.50; CDC mean = 0.13), while the combination of red and UV modified-traps excel in capturing Sergentomyia minuta sand flies (Bonferroni post-hoc test; p < 0.04; blue/UV mean = 1.19; CDC mean = 0.66). However, based on our prior studies, incorporating UV light sources into sand fly traps does not seem to enhance their attractiveness, as it has not resulted in higher capture rates. These findings contribute to understanding how sand flies’ vision and light color detection is. Further research is recommended to standardize trap construction procedures and explore variations in different endemic regions according to different sand fly species.

Molecular Detection of Leishmania spp. and Blood Source of Female Sand Flies in the Parque Estadual do Rio Doce and Municipality of Timóteo, Minas Gerais, Brazil.

Leishmaniasis is a group of diseases caused by protozoa of the genus Leishmania and is transmitted by the bite female sand fly. The present work is characterized as a descriptive study in two areas: a forest area located in the Parque Estadual do Rio Doce, and another urban area located in the municipality of Timóteo-MG, with the objective of identifying the presence of Leishmania spp. and the blood source of the collected female sand flies. Part of the females were obtained from the Parque Estadual do Rio Doce, and part was collected using 19 ligth traps distributed in residences of Timóteo. For molecular studies of Leishmania spp. DNA, the ITS1 gene was used, and in the search for blood source, the CytB gene was used and positive samples were sequenced. The study demonstrated that there are at least three species of Leishmania circulating in the study areas: Leishmania (Viannia) braziliensis, Leishmania (Leishmania) amazonensis, and Leishmania (V.) guyanensis. Nyssomyia whitmani was the predominant sand fly species in the urban area of Timóteo with a positive diagnosis for the presence of Leishmania braziliensis DNA. We found the presence of blood from Gallus gallus (Chicken) and Sus scrofa (Pig) in sand flies. The present study demonstrates that Leishmania braziliensis is the main agent of cutaneous leishmaniasis in the study area, with the effective participation of Nyssomyia whitmani as the vector and both Gallus gallus and Sus scrofa acting as a food source for female sand flies, and helping maintaining the sand fly life.

Molecular Survey of Leishmania Infection of Sand Flies in Karun County, Southwestern Iran.

Zoonotic cutaneous leishmaniasis (ZCL) is widely distributed in Iran and around the world. Also, Khuzestan Province is an endemic focus of ZCL. This study aims to investigate the natural infection of sand flies with the Leishmania parasite in Karun County. Sand flies were collected from Jangiyeh, Qaleh Chanan, Kut-e-Navaser, and Ghazavieh in the spring and summer in the year of 2019, by installing 60 sticky paper traps each time (30 traps outdoors and 30 traps indoors). Two hundred female sand flies with different abdominal conditions (empty, blood-fed, semi-gravid, and gravid) were examined for infection rate using the Nested-PCR method. In this study, seven species of sand flies including Phlebotomus papatasi, Ph. alexandri, Ph. sergenti, Ph. caucasicus, Sergentomyia tiberiadis, Se. sintoni, and Se. antennata were reported from Karun County, with a frequency of 79.64%, 16.96%, 1.07%, 0.18%, 0.36%, 1.61%, and 0.18%, respectively. Only eleven specimens of Ph. papatasi were found to be positive for Leishmania major, with an overall infection rate of 7.8%. The infection of Ph. papatasi was specifically reported in blood-fed, gravid, and semi-gravid specimens, with infection rates of 17.02%, 4.35%, and 14.29%, respectively. In this study, the infection of L. major from Ph. papatasi was reported. The results can be used in planning the control of ZCL in the study area.

Wolbachia endosymbionts in Drosophila regulate the resistance to Zika virus infection in a sex dependent manner.

Drosophila melanogaster has been used extensively for dissecting the genetic and functional bases of host innate antiviral immunity and virus-induced pathology. Previous studies have shown that the presence of Wolbachia endosymbionts in D. melanogaster confers resistance to infection by certain viral pathogens. Zika virus is an important vector-borne pathogen that has recently expanded its range due to the wide geographical distribution of the mosquito vector. Here, we describe the effect of Wolbachia on the immune response of D. melanogaster adult flies following Zika virus infection. First, we show that the presence of Wolbachia endosymbionts promotes the longevity of uninfected D. melanogaster wild type adults and increases the survival response of flies following Zika virus injection. We find that the latter effect is more pronounced in females rather than in males. Then, we show that the presence of Wolbachia regulates Zika virus replication during Zika virus infection of female flies. In addition, we demonstrate that the antimicrobial peptide-encoding gene Drosocin and the sole Jun N-terminal kinase-specific MAPK phosphatase Puckered are upregulated in female adult flies, whereas the immune and stress response gene TotM is upregulated in male individuals. Finally, we find that the activity of RNA interference and Toll signaling remain unaffected in Zika virus-infected female and male adults containing Wolbachia compared to flies lacking the endosymbionts. Our results reveal that Wolbachia endosymbionts in D. melanogaster affect innate immune signaling activity in a sex-specific manner, which in turn influences host resistance to Zika virus infection. This information contributes to a better understanding of the complex interrelationship between insects, their endosymbiotic bacteria, and viral infection. Interpreting these processes will help us design more effective approaches for controlling insect vectors of infectious disease.

A social learning primacy trend in mate-copying: an experiment in Drosophila melanogaster.

Social learning is learning from the observation of how others interact with the environment. However, in nature, individuals often need to process serial social information and may favour either the most recent information (recency bias), constantly updating knowledge to match the environment, or the information that appeared first in the series (primacy bias), which may slow down adjustment to environmental change. Mate-copying is a widespread form of social learning in a mate choice context related to conformity in mate choice, and where a naive individual develops a preference for a given mate (or mate phenotype) seen being chosen by conspecifics. Mate-copying is documented in most vertebrate taxa and in the fruit fly Drosophila melanogaster. Here, we tested experimentally whether female fruit flies show a primacy or a recency bias by presenting pictures of a female copulating with one of two contrastingly coloured male phenotypes. We found that after two sequential contradictory demonstrations, females show a tendency to prefer males of the phenotype preferred in the first demonstration, suggesting that mate-copying in D. melanogaster is not based on the most recently observed mating and may be influenced by a form of primacy bias.

Sea cucumber (Acaudina leucoprocta) peptides exhibit anti-aging effect in Drosophila melanogaster via regulation of microbiota dysbiosis and metabolic disorder

As the population ages, the pursuit of extended lifespan and improved healthspan has gained significance. This study assessed the anti-aging properties of sea cucumber peptides derived from Acaudina leucoprocta (SCP) through microbiome and metabolome analyses in Drosophila melanogaster. Supplementation with 0.2%, 0.4%, 0.6%, and 0.8% of SCP significantly boosted the survival rate and extended the mean and median lifespans in both male and female flies. Among them, 0.6% SCP treatment extended the mean and median lifespans of male flies by 21.01% and 25.48 %, which showed the most prominent lifespan-prolonging effect. Moreover, SCP enhanced the healthspan of male flies by improving their climbing ability, intestinal barrier function, and memory performance. Additionally, SCP boosted the survival rate of flies subjected to oxidative, starvation, and heat stress, with no significant effect observed under cold stress conditions. The lifespan-extension effect of SCP remained unaffected by dietary restriction, but was partially inhibited when provided with antibiotic-supplemented food. SCP modulated microbiota with increased the abundance of Lactobacillus, Rhodococcus, and Propioniciclava and decreased Acetobacter, Achromobacter, Pedobacter, and norank_f_Saprospiraceae, which closely related with lifespan-extension effect. Furthermore, SCP induced a metabolic profile in 30-day-old flies more akin to that of 3-day-old flies, impacted 13 significantly regulated metabolites associated with amino acid, nucleotide, and carbohydrate metabolisms. These findings highlight SCP intervention as a promising anti-aging strategy.

Carbon Dioxide, Methane, and Synthetic Cattle Breath Volatiles Attract Host-Seeking Stable Flies, Stomoxys calcitrans.

Stable flies, Stomoxys calcitrans (L.), are blood-feeding ectoparasites of cattle. Host-seeking stable flies respond to various cattle host cues, but a potential role of cattle breath gases [carbon dioxide (CO2), methane (CH4)] and cattle breath volatiles (acetone, isoprene, 2-butanone, 2-propanol, propionic acid, 3-methyl butyric acid, phenol), alone or in combination, on host-seeking behavior of stable flies has not yet been comprehensively investigated. In laboratory and greenhouse experiments, we tested the hypotheses that (1) CO2 and CH4 interactively attract stable flies, (2) CO2 'gates' attraction of stable flies to CH4, and (3) breath volatiles on their own, or in combination with both CO2 and CH4, attract stable flies. In Y-tube olfactometer experiments, the blend of CH4 (0.5%) and CO2 (1%) in breathing air ('b-air') attracted significantly more female flies than CH4, or CO2, in b-air. The flies' responses to CH4 were contingent upon their prior or concurrent exposure to CO2. In two-choice experiments in a large greenhouse compartment, significantly more flies landed on the host-look-alike barrel that disseminated a blend of CO2 and CH4 in b-air (CO2/CH4/b-air) than on the barrel disseminating either b-air or CO2. Moreover, significantly more flies landed on the barrel that disseminated synthetic breath volatiles (SBVs) than on the barrel disseminating b-air. The blend of CO2/CH4/b-air and SBVs elicited more fly landings on barrels than CO2/CH4/b-air but not than SBVs. SBVs, possibly combined with both CH4 and CO2, could be developed as a lure to enhance trap captures of stable flies in livestock production facilities.

Locomotor Activity of Adult Olive Fruit Flies Recorded under Conditions of Food or Water Deprivation

The olive fruit fly, known as Bactrocera oleae (Rossi) (Diptera: Tephritidae), is causing substantial economic losses in olive crops worldwide. Studying the activity patterns of the insect may expand our knowledge to eventually adopt more sustainable and effective pest control approaches. In the present study, we investigated the impact of food and water deprivation on the mobility of olive fruit flies using a modified version of the LAM25 system (locomotor activity monitor)—Trikinetics, an automated locomotor activity electronic device. Both male and female flies at four different age groups, reared on olives in the laboratory, were individually placed in glass tubes. Their locomotor activity was recorded every minute by three monitors within the digital device over a three-day period. Our observations revealed that adults exhibited significantly reduced movement during nighttime compared to daytime. The greatest mobility was observed during the period of 15:00 to 20:59. Additionally, younger flies demonstrated higher levels of mobility compared to older ones. Flies subjected to both food and water deprivation exhibited higher mobility compared to the control group. These insights offer valuable insights for enhancing pest management strategies aimed at controlling olive fruit flies adopting a more sustainable approach.

Effect of allyl-isothiocyanate on survival and antimicrobial peptide expression following oral bacterial infections in Drosophila melanogaster.

Since infections with antibiotic-resistant bacteria cause increasing problems worldwide, the identification of alternative therapies is of great importance. Plant-derived bioactives, including allyl-isothiocyanate (AITC), have received attention for their antimicrobial properties. The present study therefore investigates the impact of AITC on survival and antimicrobial peptide (AMP) levels in Drosophila melanogaster challenged with the fly pathogenic bacteria Pectobacterium carotovorum subsp. carotovorum and Leuconostoc pseudomesenteroides. AITC, a sulfur-containing compound derived from glucosinolates, exhibits antimicrobial properties and has been suggested to modulate AMP expression. By using D. melanogaster, we demonstrate that AITC treatment resulted in a concentration-dependent decrease of survival rates among female flies, particularly in the presence of the Gram-negative bacterium Pectobacterium carotovorum subsp. carotovorum, whereas AITC did not affect survival in male flies. Despite the ability of isothiocyanates to induce AMP expression in cell culture, we did not detect significant changes in AMP mRNA levels in infected flies exposed to AITC. Our findings suggest sex-specific differences in response to AITC treatment and bacterial infections, underlining the complexity of host-pathogen interactions and potential limitations of AITC as a preventive or therapeutic compound at least in D. melanogaster models of bacterial infections.

Onchocerciasis in the Cameroon–Chad border area after more than 20 years of annual mass ivermectin distribution

BackgroundThe main vectors of onchocerciasis in Africa are Simulium damnosum sensu lato, which transmit the causative agent Onchocerca volvulus. The force of transmission is driven by the vector density, hence influencing the disease prevalence and intensity. Onchocerciasis is currently targeted for elimination using mass drug administration (MDA) of ivermectin, a potent microfilaricide. MDA in Cameroon began in 1987 in the Vina Valley, an endemic cross-border area with Chad, known for high vector densities and precontrol endemicity. Evaluations in 2008–2010 in this area showed ongoing transmission, while border areas in Chad were close to interrupting transmission. This study aimed to evaluate transmission in this area after several rounds of MDA since the last evaluation surveys.MethodsBlack flies were collected by human landing catches at seven border sites in Cameroon, twice a week, from August 2021 to March 2022. A fraction of the flies was dissected for parity assessment and identification of Onchocerca larval stages. The transmission indices were estimated. Black fly larvae were also collected from the breeding sites at the fly catching sites and identified to species level by cytotaxonomy.ResultsA total of 14,303 female flies were collected, and 6918 were dissected. Of these, 4421 (64.0%) were parous. The total biting rates were high, reaching up to 16,407 bites/person/study period, and transmission potential (third-stage larvae (L3) from head/all L3) were 367/702, 146/506, 51/55, 20/32, 0/3, 0/0, and 0/0 infective larvae/person, respectively, for Mbere-Tchad, Babidan, Hajam/V5, Gor, Djeing, Touboro, and Koinderi. Infectivity rates (L3 from head) were 16.00, 12.75, 5.15, and 4.07 infective females (L3H)/1000 parous flies for Haijam, Mbere-Tchad, Babidan, and Gor, respectively. These values exceed the World Health Organization (WHO) thresholds of ≤ 20 annual transmission potential (ATP) or < 1 infective female/1000 parous females. The major vectors identified were Simulium damnosum sensu stricto, S. squamosum, and for the first time in the area, S. yahense.ConclusionsMore than 20 years of MDA has not eliminated onchocerciasis in the study area; hence, this area is a potential source of reintroduction of onchocerciasis in Chad and would require alternative treatment strategies. Many factors such as MDA efficiency, effectiveness of ivermectin, and cytospecies composition may be contributing to transmission persistence.Graphical

Effects of relative humidity on egg hatching success of blow flies (Diptera: Calliphoridae)

Humidity can influence oviposition decisions by females and the development and survival of offspring. We measured the impact of relative humidity on egg eclosion of three forensically relevant blow fly species: Lucilia sericata (Meigen), Phormia regina (Meigen) and Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae). Egg masses were placed into glass jars lined with filter paper and placed into growth chambers at 25°C with 12:12 L:D, across six levels of relative humidity (30, 40, 50, 60, 70, and 80%). Eggs were observed every six hours for eclosing larvae to measure the effect of humidity on time to egg eclosion. As relative humidity increased, time to eclosion decreased for all three species. Calliphora vicina hatching success was the least affected by humidity, maintaining greater than 60% hatching success even at 30% relative humidity. In contrast, L. sericata required at least 50% relative humidity to have hatching success above 60%. Phormia regina was the most affected by humidity, requiring relative humidity to be above 70% to reach hatching success above 60%. Given the differential effect of relative humidity on egg hatching, these results may have implications for oviposition decisions made by female blow flies.

Biology of Melon Fruit Fly &lt;i&gt;Bactrocera Cucurbitae&lt;/i&gt; (Coquillett) on Cucumber

The laboratory studies on the biology of melon fruit fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae) on cucumber revealed that eggs were shiny white, nearly flat on the ventral surface and their length and breadth were 1.29± 0.05 and 0.27± 0.02 mm, respectively while, the incubation period was 1.50± 0.51 days with 81.41± 3.61% hatching. The apodous maggot was creamy-whitish and measured 8.45± 0.40 and 1.62± 0.15 mm in length and breadth, respectively while, the total maggot period was 6.70± 0.66 days. The puparium measured 5.70± 0.47 and 2.39± 0.22 mm in length and breadth, respectively. The length and breadth with expanded wings of the male were 6.42± 0.55 and 13.50± 0.66 mm, respectively whereas, in the case of the female these were 7.89± 0.58 and 14.32± 0.65 mm, respectively. Moreover, the total life period of the female fly was recorded as 38.23± 2.80 days, while for the male it was 34.78± 1.56 days.

Bacterial peptidoglycan serves as a critical modulator of the gut-immune-brain axis in Drosophila

Metabolites and compounds derived from gut-associated bacteria can modulate numerous physiological processes in the host, including immunity and behavior. Using a model of oral bacterial infection, we previously demonstrated that gut-derived peptidoglycan (PGN), an essential constituent of the bacterial cell envelope, influences female fruit fly egg-laying behavior by activating the NF-κB cascade in a subset of brain neurons. These findings underscore PGN as a potential mediator of communication between gut bacteria and the brain in Drosophila, prompting further investigation into its impact on all brain cells. Through high-resolution mass spectrometry, we now show that PGN fragments produced by gut bacteria can rapidly reach the central nervous system. In Addition, by employing a combination of whole-genome transcriptome analyses, comprehensive genetic assays, and reporter gene systems, we reveal that gut bacterial infection triggers a PGN dose-dependent NF-κB immune response in perineurial glia, forming the continuous outer cell layer of the blood–brain barrier. Furthermore, we demonstrate that persistent PGN-dependent NF-κB activation in perineurial glial cells correlates with a reduction in lifespan and early neurological decline. Overall, our findings establish gut-derived PGN as a critical mediator of the gut-immune-brain axis in Drosophila.

Attractiveness of Golden Hamster infected with Leishmania amazonensis (Kinetoplastida: Trypanosomatidae) to laboratory-reared Lutzomyia longipalpis (Diptera: Psychodidae)

Lutzomyia longipalpis is the primary vector of Leishmania infantum in the Americas and a permissive vector for Leishmania amazonensis. Previous studies showed that Leishmania infantum-infected hosts can release different volatile organic compounds (VOCs) compared with uninfected hosts, presenting a higher attractiveness to vectors. In this study, we aimed to evaluate a possible effect of L. amazonensis infection of golden hamsters in three parameters: attractiveness to Lu. longipalpis females; blood volume ingested by sand fly females; and VOCs released by the animals.. Attractiveness was measured indirectly by the number of Lu. longipalpis females that blood fed in each L. amazonensis-infected and uninfected animal. For VOCs extraction, solid phase micro extraction fibers were used, which were analyzed by gas chromatography-mass spectrometry. Behavioral trials did not show any effect of L. amazonensis infection on the attraction of sand flies nor difference on blood meal rates of Lu. longipalpis fed in both goups of hamsters. Additionally, there was no difference between the VOCs profiles of L. amazonensis-infected or uninfected hamsters.

Insecticidal effect of new synthesized chalcone derivatives on Caribbean fruit fly, Anastrepha suspensa.

In this present study, new chalcone derivatives were synthesized from 4-aminoacetophenone, which were confirmed by spectroscopic methods. The toxic risks of chalcones to humans and the environment were investigated by a web-based platform called ADMETlab. With this program, the possible toxic effects of the compounds on liver, respiratory system, and eyes were evaluated. For the topical insecticidal activity, adult female Caribbean fruit fly, Anastrepha suspensa, was targeted. Results of the toxicity tests showed that chalcone derivatives are effective against female A.suspensa. Among the synthesized chalcones, 1-(4-cinnamoylphenyl)-3-(p-tolyl)urea (2) exhibited the greatest insecticidal activity, resulting in 73 % mortality at 100 µg/fly after 24 h, whereas other derivatives showed less than 30 % mortality. Our results demonstrate that insecticidal activity may be modulated by the presence of a certain phenyl ring in the structure of derivative 2 and, therefore, has potential for design of efficient chemicals for tephritid fruit fly management.

Alpha-ketoglutarate supplementation in long-lived Drosophila melanogaster: Impact on lifespan and metabolic responses.

Studies on antiaging remedies in insect models sometimes show discrepancies in results. These discrepancies could be explained by different responses of short- and long-lived strains on the antiaging remedies. The purpose of the study was to test whether life-prolonging effects of alpha-ketoglutarate (AKG), observed in nematodes and fruit flies, would be reproduced in long-lived Drosophila melanogaster flies. Lifespan was assayed in flies kept in demographic cages. Fecundity, proportion of flies capable of negative geotaxis, starvation resistance, time of heat coma onset, levels of triacyglycerols, body glucose, glycogen, activities of glutamate dehydrogenase, catalase, glutathione-S-transferase, hexokinase, phosphofructokinase, pyruvate kinase, lactate, and glutamate dehydrogenases were assessed. Dietary AKG did not affect fly lifespan on the diet with 5% yeast and 5% sucrose (5Y:5S) and on the diet with 9% yeast and 1% sucrose (9Y:1S), but increased lifespan on the low-protein diet (1Y:9S). Twenty-five-day-old female flies fed a 5Y:5S diet with 10 mM AKG for 3 weeks, did not differ from the control group (without AKG) in climbing activity, resistance to heat stress, and starvation. The levels of glucose and glycogen were unaffected but the levels of triacylglycerols were lower in AKG-fed female flies. No differences in activities of glycolytic enzymes, NADPH-producing enzymes, glutamate dehydrogenase, oxygen consumption, and levels of oxidative stress markers were observed between the control and AKG-fed flies. However, AKG-fed flies had lower activities of catalase and glutathione-S-transferase. These results suggest that potential antiaging remedies, such as AKG, may not extend lifespan in long-living organisms despite influencing several metabolic parameters.

ALPHA-KETOGLUTARATE INDUCES NUCLEAR RECEPTORS RATHER THAN NRF2 IN THE FRUIT FLY Drosophila melanogaster

Aim. To test whether expression of Nrf2 targets in the fruit fly Drosophila melanogaster are activated by diet supplemented with alpha-ketoglutarate (AKG). Methods. The Canton-S strain of D. melanogaster was used in the study. Female flies were reared in demographic cages (150 flies per group) on the medium containing 5% sucrose, 5% yeast, 1.2% agar, 0.18% nipagin. Experimental diet was supplemented with 10 mM disodium salt of AKG. The flies were reared during 21 days and after that were anesthetized with carbon dioxide and snap-frozen in liquid nitrogen for further biochemical studies. Expression of genes Ugt37A2, GstD2, and Cyp6a2, coding for a uridine diphosphate glycosyltransferase family 37 member A2, glutathione S-transferase D2, and cytochrome P450 6a2, respectively, respectively, was analyzed using semi-quantitative reverse transcription polymerase chain reaction followed by visualization of the products in agarose gel. The gene Tbp (TATA-box binding protein) was used as a reference gene. Results. Flies fed AKG-supplemented diet during 21 days had 2.8-fold higher level of the Cyp6a2 expression than control flies. At the same time, AKG-supplemented food did not affect expression of Ugt37A2 and GstD2 genes. Conclusions. Continuous consumption of AKG-supplemented food results in the increase in the levels of messenger ribonucleic acid of Cyp6a2 gene, a target of transcriptional factors Nrf2 and DHR96, but not Ugt37A2 and GstD2 genes. Since expression of the latter two genes was unaffected by AKG-supplemented diet, it indicates that AKG may influence other transcriptional regulators, such as nuclear receptors that have common targets with Nrf2.