Neuroprotective effects of ferulic acid and thymoquinone against deltamethrin-induced neurotoxicity in Drosophila melanogaster

Background: Recent research indicates a link between exposure to pyrethroid pesticides and negative neurodevelopmental outcomes such as neurodegenerative disorders, low intelligence quotient (IQ), and attention disorders. Thus this study aims (1) to investigate the effect of exposing Drosophila melanogaster adult male flies to 0.59 µM deltamethrin (DLM) for 24 h on their survival, climbing behavior, and acetylcholinesterase (AChE) activity, as well as the gene expression levels of ple, ddc, dat, aanat1, dop1r1, dop2r, and dopecr genes, and (2) to assess the protective effect of 250 µM Ferulic acid (FA), 25 µM Thymoquinone (TQ), and their combinations on the survival, climbing behavior, and AChE activity of D. melanogaster adult male flies exposed to 0.59 µM DLM for 72 h.Methods: In the first experiment, adult male wild-type flies were exposed to DLM incorporated into a 10% sucrose solution for 24 h, whereas, in the second experiment, they were exposed to DLM and the individual neuroprotective agents, or their mixture for 72 h.Results: Flies exposed to DLM exhibited higher mortality rates and shorter climbing distances in the negative geotaxis assay compared to control flies. Additionally, exposure to DLM upregulated the genes ddc, dat, dop1r1, dop2r, and dopecr significantly. Moreover, exposure to DLM for 72 h resulted in higher mortality rates and severe locomotor defects. However, the neuroprotective agents were effective in mitigating these toxic effects. While DLM inhibited AChE activity, concurrent exposure to FA ameliorated the inhibition.Conclusion: This study demonstrates the efficacy of natural compounds in reducing DLM-induced toxicity in D. melanogaster and highlights the potential use of this model in studying and developing therapeutic strategies for movement disorders.Keywords: Drosophila melanogaster; Neurotoxicity; Ferulic acid; Thymoquinone; Deltamethrin; Negative geotaxis    

First Record of a Spotted Fever Group \u3ci\u3eRickettsia\u3c/i\u3e sp. and \u3ci\u3eTheileria annulata\u3c/i\u3e in \u3ci\u3eHyalomma dromedarii\u3c/i\u3e (Acari: Ixodidae) Ticks in the United Arab Emirates

Rickettsiosis and theileriosis can cause mortalities in camel populations. This study was conducted to achieve 2 objectives: (1) to detect the presence of SFG Rickettsia sp. and Theileria sp. in Hyalomma dromedarii Koch, 1844 (Acari: Ixodidae) ticks and (2) to determine their prevalence in the tick population on the sampled camel farms in Al-Ain, United Arab Emirates (UAE). Camel ticks (H. dromedarii) were collected from a total of 625 one-humped camels (Camelus dromedarius) in 22 sampling locations in Al-Ain, UAE. Tick samples were analyzed by Polymerase Chain Reaction (PCR). An SFG Rickettsia sp., which was 99% similar to Candidatus \u27Rickettsia andeanae\u27 and Rickettsia endosymbionts, was detected only in 2011 and its prevalence in the sampled ticks was 1.12%, while Theileria annulata was detected in both years with a prevalence of 2.3% and 1.60%, respectively. Additionally, T. annulata was present in all of the sampling zones (east, west, north, and south) of the study area, whereas SFG Rickettsia sp. was limited to 2 zones only (east and south). The geographic distributions of SFG Rickettsia sp. and T. annulata showed no overlap throughout the entire study area except in one location in which both of the disease agents were present. This study is the first published record on the presence of SFG Rickettsia sp. and T. annulata in camel ticks in the UAE. In addition, the current study should serve as a foundation for more studies leading to a better understanding of the reservoir potential of camels and the risk posed by these 2 disease agents to camels and other livestock

Prevalence, distribution on host's body, and chemical control of camel ticks Hyalomma dromedarii in the United Arab Emirates

Background and Aim: Camel farming remains a part of the culture of the Arabian Peninsula although modern methods have greatly increased camel densities in the entire region. In the United Arab Emirates (UAE), camel production is threatened by tick parasitism. However, no study has considered assessing the magnitude of the problem in the UAE. We conducted a study evaluating tick richness, abundance, and spatial distribution of ticks on camels in farms near Al Ain, UAE. In addition, we conducted a survey of farm owners to determine the control methods used to eliminate camel ticks. Materials and Methods: Tick counts were made on 502 camels (Camelus dromedarius). For each examined animal, visual counts of ticks were made on the entire body segregating the counts by head, neck, forelegs, hump, abdomen, back legs, and tail area. In addition, a total of 70 camel owners from the study area were randomly selected and surveyed about the tick control methods. Results: Hyalomma dromedarii was the only species found during the study. The prevalence of ticks was 98% among the sampled animals. The mean intensity (tick load) was 25.8±2.4 ticks/host and the maximum number of ticks per animal was 102. Ticks were found in five vicinities that are on the border with Oman. The highest number of ticks on the body of the camel occurred on the tail area followed by the abdomen. Cypermethrin was the most commonly used acaricide (46.9%). Conclusion: The high abundance of ticks reported in this study calls for the establishment of a good management strategy. In addition, finding ticks in vicinities in the UAE that are on the border with Oman suggests a cross-border movement between the two countries. Therefore, studying this movement is important to understand its role in the global circulation of some H. dromedarii tick-borne diseases and the movement of acaricide resistance alleles among tick populations

Population Dynamics of Hyalomma dromedarii on Camels in the United Arab Emirates

Hyalomma dromedarii is the most important tick species infesting camels in the Middle East. So far, there are no studies on the population dynamics of H. dromedarii ticks on camels in the United Arab Emirates (UAE). Thus, the current study was performed: (1) to assess H. dromedarii population dynamics under common camel breeding and management practices in the study area, (2) to evaluate H. dromedarii life stage changes and sex ratio over time, and (3) to measure parasitological indicators of H. dromedarii infestation. We conducted monthly on-site tick visual counts and collection from camels in Al Ain, UAE, over 12 months. Our results show that the infestation prevalence was very high during the whole study period, with a mean of 94.33%. The maximum infestation intensity occurred in June, while the minimum occurred in January. Overall, H. dromedarii ticks were found on camels during the entire year in spite of monthly applications of an acaricide. This study reveals that H. dromedarii has a very high prevalence and continuous presence on camels in the UAE regardless of the weather fluctuations and acaricide applications and showed the need for an effective control strategy

Dynastid beetle pests

Two main species of dynastid or rhinoceros beetle (Coleoptera: Scarabaeoidea: Scarabaeidae: Dynastinae: Tribe Oryctini) Oryctes elegans, and subspecies of Oryctes agamemnon, attack date palms causing significant and documented damage. Adults of O. elegans bore into the stalks of inflorescences and fruit bunches to feed, and oviposit in leaf axils where the larvae develop and may invade the trunk. Oryctes agamemnon larvae bore into frond bases, the trunk, and respiratory roots where their tunnelling may cause the palm to fall. It is difficult to distinguish the larvae of the two species in regions where both coexist. For control, annual servicing of palms includes cutting off old fronds at their bases using the correct technique which enables removal of larvae and their breeding places, and this may be integrated with light trapping for catching adults. Quarantine measures may hinder the spread of these pests to uninfested areas. In India, adults of a third species, O. rhinoceros, have been noted boring into the soft tissue of the growing point, and this species has also been reported from Yemen. Pheromone trapping is available for O. elegans but for effectiveness it requires the addition of fresh date palm tissue to the traps as a synergist. The entomopathogenic fungus Metarhizium anisopliae and the nematode Rhabditis sp. may have potential in integrated pest management but their possible natural occurrence in an area should be determined, prior to propagation and release. The pathogenic Oryctes Nudivirus, was successful against Oryctes rhinoceros in lowering its populations and damage to coconut palms when introduced into areas where this virus did not previously exist, and should be tested against date palm dynastids. Oryctes agamemnon and O. elegans adults attacking date palms do not appear to bore into the heart or meristem causing V-cuts to unfurling fronds or the death of the palm, in contrast to attacks by O. rhinoceros on coconut and young oil palms. Also O. rhinoceros larvae are found only in dead decomposing wood or other organic material, whereas larvae of date palm pests O. elegans and O. agamemnon may tunnel in living tissues.36 page(s

kdr mutations and deltamethrin resistance in house flies in Abu Dhabi, UAE

Abstract Background The house fly, Musca domestica, is a significant carrier of diseases that can impact public health. Repeated use of pyrethroid insecticides may act as a selection pressure for mutations and amino acid substitutions in the house fly voltage-sensitive sodium channel (VSSC), which ultimately confers resistance. The objectives of this study were to determine the presence of knockdown resistance (kdr) mutations using molecular tools and to set up a CDC bottle bioassay specific for house flies in the United Arab Emirates (UAE) to screen for deltamethrin resistance. Methods Adult flies were collected from 19 locations in Abu Dhabi, UAE, and DNA was extracted, followed by PCR amplification of specific alleles (PASA) and conventional PCR using several primers to amplify regions of the VSSC gene. Sanger sequencing was performed on PCR products. We also designed primers that detect four kdr mutations using complementary DNA (cDNA) in reverse transcriptase (RT)-PCR followed by Sanger sequencing. Additionally, a CDC bottle bioassay was set up for detecting deltamethrin resistance in adult house flies. Results In PASA, the primers successfully amplified the target bands (480, 280 and 200 bp). The kdr allele was found in flies collected from 18 of the 19 locations, at the highest and lowest prevalence of 46.9% and 9.4%, respectively. Resistant homozygous (RR) insects constituted 5.0% of the tested populations, and heterozygous (RS) insects accounted for 36.5%. The RR genotype was prevalent in house flies collected at 10 of 19 sampling locations. House fly populations were mostly in Hardy–Weinberg equilibrium, except in three locations. In addition to verifying the presence of the previously identified kdr mutation L1014F, in this study we detected two kdr mutations, L1014H and T929I, that have not previously been reported in the UAE. Also, for the first time in the UAE, a CDC bottle bioassay for deltamethrin resistance was used, which found that 60 min and 4.5 µg/ml were the diagnostic time and dose, respectively. Using this assay, we detected deltamethrin resistance in house flies from two of 16 locations, with a resistance level of 12.5%. Conclusions Using DNA sequencing, we confirmed the presence of a known kdr mutation and uncovered two new kdr mutations in house flies from Abu Dhabi. Additionally, we detected deltamethrin resistance in these flies using a CDC bottle bioassay. Further research is recommended to comprehensively identify more kdr mutations in UAE house fly populations and assess their impacts on control strategies. Graphical Abstrac