Ongoing transmission of onchocerciasis in the Pru District of Ghana after two decades of mass drug administration with ivermectin and comparative identification of members of the Simulium damnosum complex using cytological and morphological techniques.

BACKGROUND: Human onchocerciasis remains a public health problem in Ghana. Mass drug administration (MDA) with ivermectin (IVM) has reduced disease morbidity and prevalence, but the transmission of onchocerciasis remains ongoing in several endemic foci. We investigated parasite transmission in some endemic communities in Ghana that had received > 18 rounds of annual MDA with IVM and determined the species composition of black fly (Simulium damnosum) vectors in these areas. METHODS: Adult female black flies were collected using human landing catches and identified as either forest or savanna species using morpho-taxonomic keys. The adult flies underwent dissection to determine their parity and detect any O. volvulus larvae, followed by the calculation of entomological indices. Simulium damnosum s.l. larvae were collected and preserved in freshly prepared Carnoy's fixative and were later used for cytotaxonomic studies. RESULTS: A total of 9,983 adult flies were caught: 6,569 and 3,414 in the rainy and dry seasons respectively. Black fly biting activities over the study period showed bimodal or trimodal patterns. The highest monthly biting rate (MBR) of 10,578.75 bites/person/month was recorded in July in Beposo, while the highest monthly transmission potential of 100.69 infective bites/person/month was recorded in Asubende in August. Morphological analysis of 2,032 flies showed that 99.8% (2,028) of the flies were savanna species, with only 4 (0.2%) adult flies being of the forest species. Cytogenetic studies on 114 black fly larvae revealed three cytospecies (Simulium damnosum s.s., S. sirbanum and S. sanctipauli) in the study area. CONCLUSIONS: The present studies confirmed an ongoing transmission of onchocerciasis in the study communities except Abua-1. It also provides further information on biting behaviors and onchocerciasis transmission indices in the study communities. Further, our data confirmed the savanna species (S. damnosum s.s. and S. sirbanum) of the S. damnosum s.l. to be the major vectors of onchocerciasis in the study areas, with only an occasional influx of forest cytotypes.

Effect of nine pesticides against the date palm mite, Oligonychus afrasiaticus (Acari: Tetranychidae) and the predatory mite, Amblyseius swirskii (Acari: Phytoseiidae) under laboratory and field conditions.

Date palm trees, their cultivation and harvesting have become challenging due to infestations caused by some specific mites including Oligonychus afrasiaticus (McGregor) (Tetranychidae). Current research has been carried out to investigate the efficiency of nine pesticides against eggs and date palm mite, Oligonychus afrasiaticus against nine pesticides. Side effects of the nine pesticides were also examined on predatory mite, Amblyseius swirskii Athias-Henriot (Phytoseiidae). Mites and their eggs were treated with the recommended dosage of nine pesticides namely, Bifenazate 24%, Bifenthrin 10%, Matrine 0.6%, Imidacloprid 37% + Abamectin 3%, Sulphur 99.5%, Micronized Sulphur 80%, Mineral oil 95%, Pyrethrin 1.5% and Hexythiazox 10%, while they were present in their natural environment on the date palm trees in the experimental fields. Highest mortality of 91.16% was observed when O. afrasiaticus was treated with Bifenazate (24%) followed by 87.31%, 85.20%, 72.06%, 71.34%, 65.35%, 64.14%, 61.06% and 24.25% in case of Bifenthrin 10%, Matrine 0.6%, Imidacloprid 37% + Abamectin 3%, Sulphur 99.5%, Micronized Sulphur 80%, Mineral oil 95%, Pyrethrin 1.5%, and Hexythiazox 10%, respectively. A minimum hatching of 25.74% was observed when eggs of O. afrasiaticus were treated with Hexythiazox 10% and the highest success of hatching (99.07%) was seen when treatment was given with Imidacloprid 37% + Abamectin 3%. When same trials with same nine pesticides were performed on predatory mite; Amblyseius swirskii, the highest mortality in terms of percentage reduction (75.63%) was observed with Bifenthrin and the lowest (14.69%) with Matrine. Nine pesticides used in this study have distinct toxicity against targeted mite, their eggs and the predatory mite. A two steps control strategy is recommended for this treatment. First spray Hexythiazox at the egg laying stage and then at the moving stage of mites by using Matrine which is toxic to mites but negligibly toxic to predatory mites. Further studies are recommended to evaluate varied actions of the pesticide against eggs, phytophagous mites, and predatory mites.

Avermectin B1 mediates antitumor activity and induces autophagy in osteosarcoma through the AMPK/ULK1 signaling pathway.

BACKGROUND: Osteosarcoma is the most common malignant bone tumor in children and adolescents. Conventional chemotherapy remains unsatisfactory due to drug toxicity and resistance issues. Therefore, there is an urgent need to develop more effective treatments for advanced osteosarcoma. In the current study, we focused on evaluating the anticancer efficacy of avermectin B1, a novel avermectin analog, against osteosarcoma cells. METHODS: The half-inhibitory concentration of avermectin B1 was calculated in three osteosarcoma cell lines. Then, functional experiments were conducted to evaluate the effects of avermectin B1 on cell proliferation, the cell cycle, apoptosis and autophagy. Moreover, the AMPK/ULK1 signaling pathway was detected by Western blot assay. Finally, the in vivo effect of avermectin B1 on tumor growth and metastasis was investigated using the xenograft mouse model. To examine the role of the AMPK/ULK1 pathway, an AMPK-specific inhibitor (dorsomorphin) was used in combination with avermectin B1. RESULTS: Avermectin B1 inhibited the proliferation of osteosarcoma cells in a dose-dependent manner based on CCK8 and colony formation assays. Then, it was found to inhibit migration and invasion by wound healing assay and cell migration and invasion assay. In addition, avermectin B1 induced osteosarcoma cell apoptosis and autophagy. In vivo, avermectin B1 effectively inhibited osteosarcoma cell growth and pulmonary metastasis. Mechanistically, avermectin B1 activated the AMPK/ULK1 pathway to exert antitumor activity in vitro and in vivo. Dorsomorphin significantly attenuated the Avermectin B1-induced antitumor activities. CONCLUSION: Our study suggests that avermectin B1 is a potential agent to treat osteosarcoma cells through the AMPK/ULK1 signaling pathway.

Cationic Amphiphilic Comb-Shaped Polymer Emulsifier for Fabricating Avermectin Nanoemulsion with Exceptional Leaf Behaviors and Multidimensional Controlled Release.

The development of intelligent multifunctional nanopesticides featuring enhanced foliage affinity and hierarchical target release is increasingly pivotal in modern agriculture. In this study, a novel cationic amphiphilic comb-shaped polymer, termed PEI-TA, was prepared via a one-step Michael addition between low-molecular-weight biodegradable polyethylenimine (PEI) and tetradecyl acrylate (TA), followed by neutralization with acetic acid. Using the emulsifier PEI-TA, a positively charged avermectin (AVM) nanoemulsion was prepared via a phase inversion emulsification process. Under optimal formulation, the obtained AVM nanoemulsion (defined as AVM@PEI-TA) demonstrated exceptional properties, including small size (as low as 67.6 nm), high encapsulation efficiency (up to 87.96%), and high stability toward shearing, storage, dilution, and UV irradiation. The emulsifier endowed AVM@PEI-TA with a pronounced thixotropy, so that the droplets exhibited no splash and bounce when they were sprayed on the cabbage leaf. Owing to the electrostatic attraction between the emulsifier and the leaf, AVM@PEI-TA showed improved leaf adhesion, better deposition, and higher washing resistance in contrast to both its negatively charged counterpart and AVM emulsifiable concentrate (AVM-EC). Compared to the large-sized particles, the small-sized particles of the AVM nanoemulsion more effectively traveled long distances through the vascular system of veins after entering the leaf apoplast. Moreover, the nanoparticles lost stability when exposed to multidimensional stimuli, including pH, temperature, esterase, and ursolic acid individually or simultaneously, thereby promoting the release of AVM. The release mechanisms were discussed for understanding the important role of the emulsifier in nanopesticides.

Streptomyces avermitilis MICNEMA2022: a new biorational strain for producing abamectin as an integrated nematode management agent.

BACKGROUND: Abamectin (ABA) is considered a powerful insecticidal and anthelmintic agent. It is an intracellular product of Streptomyces avermitilis; is synthesized through complicated pathways and can then be extracted from mycelial by methanol extraction. ABA serves as a biological control substance against the root-knot nematode Meloidogyne incognita. This investigation is intended to reach a new strain of S. avermitilis capable of producing ABA effectively. RESULTS: Among the sixty actinobacterial isolates, Streptomyces St.53 isolate was chosen for its superior nematicidal effectiveness. The mycelial-methanol extract of isolate St.53 exhibited a maximum in vitro mortality of 100% in one day. In the greenhouse experiment, the mycelial-methanol extract demonstrated, for the second-stage juveniles (J2s), 75.69% nematode reduction and 0.84 reproduction rate (Rr) while for the second-stage juveniles (J2s), the culture suspension demonstrated 75.38% nematode reduction and 0.80 reproduction rate (Rr). Molecular identification for St.53 was performed using 16 S rRNA gene analysis and recorded in NCBI Genbank as S. avermitilis MICNEMA2022 with accession number (OP108264.1). LC-MS was utilized to detect and identify abamectin in extracts while HPLC analysis was carried out for quantitative determination. Both abamectin B1a and abamectin B1b were produced and detected at retention times of 4.572 and 3.890 min respectively. CONCLUSION: Streptomyces avermitilis MICNEMA2022 proved to be an effective source for producing abamectin as a biorational agent for integrated nematode management.

Sublethal effect of emamectin benzoate on age-stage, two-sex life table and population projection of red palm weevil, Rhynchophorus ferrugineus.

The red palm weevil (RPW), Rhynchophorus ferrugineus Olivier, is a devastating insect-pest of 29 plants including date palm. It feeds inside the tree bark thus it is difficult to manage using insecticides. Only a few insecticides have been found effective against RPW. Among these insecticide, emamectin benzoate (EMB) is widely used. This insecticide can pose threat human and environmental health as it is used in the form of tree injection. Thus, keeping in view its possible, its sublethal effect on RPW was studied using Age-stage, two sex life table. Life table parameters of the progeny of exposed larvae to LC10, LC25, and LC50 of EMB were computed. Statistically higher fecundity (161.12 per female) was observed in control treatment, while less fecundity was observed in LC50 treatment. Significantly higher values for intrinsic rate of increase (r), finite rate of increase (λ), and net reproductive rate (Ro) (0.0376, 1.0383, and 67.13 per day, respectively) were recorded for the control treatment. Contrarily, lower values for r, Ro, and λ i.e. 0.0318, 23.82, and 1.0324 per day, respectively were recorded in the LC50 treatment. Decreased population parameters suggest that EMB can be successfully used in for the management of RPW.

Long-lasting, UV shielding, and cellulose-based avermectin nano/micro spheres with dual smart stimuli-microenvironment responsiveness for Plutella xylostella control.

The requirement to improve the efficiency of pesticide utilization has led to the development of sustainable and smart stimuli-responsive pesticide delivery systems. Herein, a novel avermectin nano/micro spheres (AVM@HPMC-Oxalate) with sensitive stimuli-response function target to the Lepidoptera pests midgut microenvironment (pH 8.0-9.5) was constructed using hydroxypropyl methylcellulose (HPMC) as the cost-effective and biodegradable material. The avermectin (AVM) loaded nano/micro sphere was achieved with high AVM loading capacity (up to 66.8 %). The simulated release experiment proved the rapid stimuli-responsive and pesticides release function in weak alkaline (pH 9) or cellulase environment, and the release kinetics were explained through release models and SEM characterization. Besides, the nano/micro sphere size made AVM@HPMC-Oxalate has higher foliar retention rate (1.6-2.1-fold higher than commercial formulation) which is beneficial for improving the utilization of pesticides. The in vivo bioassay proved that AVM@HPMC-Oxalate could achieve the long-term control of Plutella xylostella by extending UV shielding performance (9 fold higher than commercial formulation). After 3 h of irradiation, the mortality rate of P. xylostella treated by AVM@HPMC-Oxalate still up to 56.7 % ± 5.8 %. Moreover, AVM@HPMC-Oxalate was less toxic to non-target organisms, and the acute toxicity to zebrafish was reduced by 2-fold compared with AVM technical.

Comparative effect of ivermectin and amitraz on cellular architecture of ovaries, synganglion and Gené's organ of Rhipicephalus microplus (Acari: Ixodidae).

The present study investigated the effect of ivermectin and amitraz on the cellular architecture of vital organs of Rhipicephalus microplus. Adult female ticks were treated with lethal concentrations (LC95) of ivermectin and amitraz, and the ovaries, synganglion, and Gené's organ were processed 48 h post treatment. In both the treatment groups, the ultra-thin sections of ovary exhibited deformed oocytes, irregular plasmic membrane and chorion layer, extensive vacuolation in the cytoplasm mainly at periphery of the cell and oocyte-pedicel junction. Marked vacuolations in the cortex and neuropile region with significant structural disorganization of the neural fibers were common alterations observed in the synganglion of ticks exposed to ivermectin and amitraz. The tissue sections of Gené's organ revealed deformed tubular glands with severe loss of cellular limit of secretory epithelium and cytoplasmic vacuolations in the ivermectin treated ticks whereas, the alterations were comparatively less severe in amitraz exposed ticks. The cellular deformities in these vital organs probably impaired reproductive function, nerve signal transmission and metabolic activities and thus affected fecundity and survivability of the treated ticks. The findings suggested that the action of ivermectin and amitraz are not restricted to the nervous system of ticks, but also on other vital organs, ovary and Gené's organ affecting the oviposition. The study provided insights into the development of targeted interventions for tick control strategies.

Evaluation of muscular apoptotic changes and myogenin gene expression in experimental trichinosis after stem cells and atorvastatin added to ivermectin treatment.

Trichinosis is a common parasitic disease that affects the striated skeletal muscles, causing apoptotic and degenerative changes associated with myogenin expression in the affected myocytes. Hence, this study aimed to assess the ameliorative effects of stem cells and atorvastatin added to ivermectin on the infected myocytes during the muscular phase of murine trichinosis. 120 laboratory Swiss albino male mice were divided into 10 groups, and each group was subdivided into intestinal and muscular phases (each n = 6); uninfected control; untreated infected control; infected received ivermectin monotherapy; infected received atorvastatin monotherapy; infected received stem cells monotherapy; infected received ivermectin and atorvastatin dual therapy; infected received ivermectin and stem cells dual therapy; infected received atorvastatin and stem cells dual therapy; infected received ivermectin 0.2, atorvastatin 40, and stem cells triple therapy; and infected received ivermectin 0.1, atorvastatin 20, and stem cells triple therapy. Intestinal phase mice were sacrificed on the 5th day post-infection, while those of the muscular phase were sacrificed on the 35th day post-infection. Parasitological, histopathological, ultrastructural, histochemical, biochemical, and myogenin gene expression assessments were performed. The results revealed that mice that received ivermectin, atorvastatin, and stem cell triple therapies showed the maximum reduction in the adult worm and larvae burden, marked improvement in the underlying muscular degenerative changes (as was noticed by histopathological, ultrastructural, and histochemical Feulgen stain assessment), lower biochemical levels of serum NK-κB and tissue NO, and lower myogenin expression. Accordingly, the combination of stem cells, atorvastatin, and ivermectin affords a potential synergistic activity against trichinosis with considerable healing of the underlying degenerative sequel.

Ovicidal activity of diaryl dichalcogenides and ivermectin on Fasciola hepatica: A novel candidate for a blending-based therapeutic strategy.

Fasciolosis is a food and waterborne disease caused by Fasciola spp., representing a global health burden to various hosts, including humans and other animals. This study investigates the in vitro activity of tellurium- and selenium-containing diaryl dichalcogenides: diacetal ditelluride (LQ07), diacetal diselenide (LQ62), and diacetyl diselenide (LQ68) alone and in combination with ivermectin (IVM) against eggs of Fasciola hepatica. The eggs were exposed for 12 h with each organochalcogen (OC) (0.1 - 2 mmol l-1) and IVM (0.01 - 2 mmol l-1) following an incubation of 15 days, allowing embryonation. The inhibitory concentration of 50 % (IC50) of each OC or IVM was tested with the IC10, IC30, and IC50 of IVM or each OC, respectively. LQ07, LQ62, and LQ68, as well as IVM, demonstrated a concentration-dependent ovicidal activity. The peak ovicidal activity of 99.74 % was achieved when IVM was tested at 2.0 mmol l-1. LQ62 and LQ68 demonstrated greater ovicidal activity, having an IC50 < 0.32 mmol l-1 being 6.25-fold more toxic than IVM alone. The percentage of dead eggs was significantly higher in the IVM group (early mortality), as Se-containing OCs led to the (miracidia) embryonation of the eggs with no hatching (late mortality). Blending Se-containing OCs and IVM showed an additive effect of up to 27 % against F. hepatica eggs. The present data contribute to the potential use of blending-based therapeutic strategies to combat F. hepatica infections in eradication programs worldwide. The combinations may also act against multidrug-resistant strains, reinstating drug-based parasite control.

Impact of blood meals taken on ivermectin-treated livestock on survival and egg production of the malaria vector Anopheles coluzzii under laboratory conditions.

Treatment of livestock with endectocides such as ivermectin is viewed as a complementary vector control approach to address residual transmission of malaria. However, efficacy of this treatment may vary between animal species. Hence, our purpose was to investigate the effects of ivermectin treatments of common livestock species on life history traits of the opportunistic malaria vector Anopheles coluzzii. Sheep, goats and pigs were treated using injectable veterinary ivermectin formulation at the species-specific doses (recommended dose for all species and high dose in pig). Mosquito batches were exposed to treated and control (not injected) animals at different days after treatment. Daily mosquito mortality was recorded and fecundity assessed through the count of gravid females and the number of eggs they developed. The recommended dose of ivermectin induced a significant decrease in mosquito survival for up to 7 days after injection (DAI), with a decrease of 89.7%, 66.7%, and 48.4% in treated pigs, goats and sheep, respectively, compared to control animals. In treated pigs, the triple therapeutic dose decreased mosquito survival of 68.97% relatively to controls up to 14 DAI. The average number in gravid females Anopheles that survived after feeding on treated animals were reduced when blood-meals were taken on sheep (2.57% and 42.03% at 2 and 7 DAI), or on goats (decrease of the 28.28% and 73.64% respectively at 2 and 7 DAI). This study shows that ivermectin treatments to animals negatively impacts An. coluzzii life history traits and could reduce vector densities in areas where livestock live near humans. However, due to short-term efficacy of single dose treatments, repeated treatments and potentially increased dosages would be required to span the transmission season. The use of long-acting ivermectin formulations is discussed as a mean for extending efficacy while remaining cost effective.

Fitness costs, realized heritability, and mechanism of resistance to tenvermectin B in Plutella xylostella.

Tenvermectin B (TVM-B) and five TVM-B analogs were produced by fermentation of a genetically engineered strain Streptomyces avermitilis HU02, and TVM-B is being developed as a new insecticide. Through 11 generations of resistance selection against TVM-B in the diamondback moth, Plutella xylostella, the median lethal concentration (LC50) was increased from 14.84 to 1213.73 mg L-1. The resistance to TVM-B in P. xylostella developed fast and its realized heritability was high (h2 = 0.2901 (F7), h2 = 0.4070 (F11)). However, the relative fitness was 0.6916 suggesting a fitness cost in the resistant strains. The fitness cost was partially explained by the upregulation of the detoxification enzyme activity by 2.15 folds in carboxylate esterase (CarE) and the gene expressions of ATP-binding cassette transporter gene (ABCC2) and the alpha subunit of the glutamate-gated chloride channel (GluCl) by 1.70- and 2.32 folds, respectively. The resistance was also explained by two points of mutations at the alpha subunit of the glutamate-gated chloride channel in the P. xylostella (PxGluClα) subunit in F11. However, there was little change in the binding affinity. These results provided helpful information for the mechanism study of TVM-B resistance and will be conducive to designing rational resistance management strategies in P. xylostella.

Strain-level variations of Dirofilaria immitis microfilariae in two biochemical assays.

BACKGROUND: The increase in reports of resistance to macrocyclic lactones in the canine heartworm, Dirofilaria immitis is alarming. While DNA based tests have been well-validated, they can be expensive. In a previous study, we showed that two biochemical tests adapted to a 96- well plate format and read in a spectrophotometer could detect differences among lab validated D. immitis isolates. The two tests- Resazurin reduction and Hoechst 33342 efflux-detect metabolism and P-glycoprotein activity respectively in microfilariae isolated from infected dog blood. METHODS: Our objective was to optimize the two assays further by testing various assay parameters in D. immitis isolates not tested previously. We tested microfilarial seeding density, incubation time and the effect of in vitro treatment with ivermectin and doxycycline in five other D. immitis isolates-JYD-34, Big Head, Berkeley, Georgia III and LOL. All assays were performed in 3 technical replicates and 2-4 biological replicates. To understand the molecular basis of the assays, we also performed qPCR for selected drug metabolism and elimination associated genes of the ABC transporter and cytochrome P450 gene families. RESULTS: Metabolism and ABC transporter activity as detected by these assays varied between strains. Anthelmintic status (resistant or susceptible) did not correlate with metabolism or P-gp efflux. Basal transcriptional variations were found between strains in ABC transporter and cytochrome P450 genes. CONCLUSIONS: These assays provide a greater understanding of the biochemical variation among isolates of D. immitis, which can be exploited in the future to develop in vitro diagnostic tests capable of differentiating susceptible and resistant isolates.

The effect of anthelmintic treatment and efficacy on the faecal microbiota of healthy adult horses.

Changes to the faecal microbiota of horses associated with administration of anthelmintic drugs is poorly defined. This study included horses with cyathostomin infection where susceptibility and resistance to oxfendazole and abamectin was known. This study assessed the changes to the faecal microbiota associated with administration of two different anthelmintics in this population. Twenty-four adult horses were included. Faecal egg counts were performed on all horses prior to random allocation into abamectin (n=8), oxfendazole (n=8) or Control groups (n=8) and at Day 14 post treatment. Faecal samples were collected for microbiota analysis prior to anthelmintic administration and on Day 3 and Day 14. From each faecal sample, DNA was extracted prior to PCR amplification, next generation sequencing and analysis using QIIME2. Anthelmintic treatment was associated with changes in alpha diversity (p <0.05), with increased evenness and diversity at Day 14 and increased richness at Day 3 within the abamectin group. Differences in relative abundance of bacteria at the phyla, family and genus taxonomic levels occurred after treatment; indicating that the microbiota was altered with anthelmintic administration. The results support that anthelmintic administration and removal of cyathostomins from the large intestine of horses is associated with changes in the faecal microbiota. The results suggest that removal of cyathostomins is associated with greater differences in microbiota, compared to anthelmintic drug administration that is ineffective in reducing cyathostomin infection. Cyathostomin removal was supported by adequate reduction of faecal egg counts, determined by faecal egg count reduction testing.

The cytochrome P450 gene CYP4g1 driven by high temperature confers abamectin tolerance on Liriomyza trifolii through promoting cuticular hydrocarbons biosynthesis.

Liriomyza trifolii, an invasive pest, poses a substantial threat to horticultural and vegetable plants. It spreads rapidly, especially in hot weather, leading to large-scale outbreaks with strong thermotolerance and insecticide resistance. In this study, mortality and LtCYP4g1 expression in L. trifolii were evaluated after thermal and insecticides exposure. Furthermore, functional verification of LtCYP4g1 was conducted through RNA interference and bacterial survival assays in Escherichia coli containing recombinant LtCYP4g1 protein. Results indicated that a short time exposure to high temperature incresed insecticide tolerance of L. trifolii, attributed to decreased mortality and induced LtCYP4g1 expression; LtCYP4g1 was involved in stimulating synthesis of cuticular hydrocarbons (CHCs) and elevating epicuticle lipid content and thickness, and E. coli cells overexpressing LtCYP4g1 exhibited significant tolerance to thermal and insecticide stress. In general, P450-mediated tolerance of L. trifolii was enhanced by high temperature, with LtCYP4g1 playing a role in promoting biosynthesis of CHCs for thickening epidermal lipid barrier and reducing cuticular penetration. This study provides a framework for delving into the function of CYP450s in insecticide detoxification and illustrates the role of global warming in driving the evolution of L. trifolii.

Doramectin attenuates inflammation, obesity and insulin resistance in food-borne obese mice.

The avermectin derivative doramectin is widely used clinically as an antiparasitic drug and, in addition, doramectin may have a modulatory role in obesity. Adipose tissue macrophage recruitment and polarization play an important role in obesity-induced inflammation and insulin resistance. The aim of this study was to investigate the effects of doramectin on high-fat diet-induced inflammation and macrophage polarization in white adipose tissue of epididymis of obese mice. We found that compared with high-fat diet-fed obese mice, doramectin treatment resulted in a significant decrease in body weight and lipid levels, improved insulin resistance, an increase in the proportion of M2-type macrophages and a decrease in the proportion of M1-type macrophages in the epididymal white adipose tissues, as well as a decrease in the infiltration of inflammatory cells in the adipose tissues. Thus, doramectin can ameliorate high-fat diet-induced obesity and adipose inflammation by affecting macrophage polarization in white adipose tissue.

Overcoming flumatinib resistance in chronic myeloid leukaemia: Insights into cellular mechanisms and ivermectin's therapeutic potential.

Chronic myeloid leukaemia (CML) is a haematological malignancy characterized by the constitutive tyrosine kinase activity of the BCR-ABL1 fusion protein. Flumatinib, a second-generation tyrosine kinase inhibitor, has exhibited superior clinical efficacy compared to its precursor, imatinib. However, with increased clinical use, resistance to flumatinib has emerged as a significant challenge. To investigate the mechanisms of flumatinib resistance in CML, we induced the human CML cell line K562 using a flumatinib concentration gradient method in vitro, successfully establishing a flumatinib-resistant K562/FLM cell line. This cell line exhibited cross-resistance to imatinib and doxorubicin, but remained sensitive to the antiparasitic agent ivermectin, which possesses antitumoural effects. Through cellular experimentation, we explored the resistance mechanisms, which indicated that K562/FLM cells evade flumatinib cytotoxicity by enhancing autophagy, increasing the expression of membrane transport proteins, particularly P-glycoprotein, ABCC1 and ABCC4, as well as enhancing phosphorylation of p-EGFR, p-ERK and p-STAT3 proteins. Moreover, it was found that ivermectin effectively suppressed the expression of autophagy and transport proteins in K562/FLM cells, reduced the activity of the aforementioned phosphoproteins, and promoted apoptotic cell death. Collectively, the increased autophagy, higher expression of drug-efflux proteins and hyperactivation of the EGFR/ERK/STAT3 signalling pathway were identified as pivotal elements promoting resistance to flumatinib. The significant effects of ivermectin might offer a novel therapeutic strategy to overcome flumatinib resistance and optimize the treatment outcomes of CML.

Evaluation of ivermectin and vitamin E based combination with antiseizure rufinamide drug for mitigation of pentylenetetrazole-induced kindling, behavioral challenges and histopathological aberrations.

Pentylenetetrazole- (PTZ)-induced kindling is a broadly used experimental model to evaluate the impact of antiseizure drugs and their novel combination on seizure progression. The current study aimed to evaluate the anti-kindling effects of ivermectin (IVM) and rufinamide (RUFI) alone and their combination with vitamin E. The mice were administered 11 injections of PTZ (40 mg/kg) followed by assessment for anxiety-like behavior and cognitive abilities in a series of behavior tests with subsequent brain isolation for biochemical and histopathological evaluation. The outcomes showed a marked protection by IVM + RUFI (P<0.001) from kindling progression, anxiety-like behavior and cognitive deficit. However, additional supplementation with vitamin E worked superior to duo therapy as these mice were noted to be most fearless to visiting open, illuminated and elevated zones of open field, light/dark and elevated-plus maze (P<0.0001). Further, they showed marked remembrance of the familiar milieu in y-maze (P<0.01) and novel objection recognition (P<0.05) tests. Additionally, their recollection of aversive stimuli in passive avoidance and spatial memory in Morris water maze were evident (P<0.0001), in comparison to kindled mice. The IVM + RUFI duo therapy and its co-administration with vitamin E prevented kindling-triggered oxidative stress in brains and neuronal damage in hippocampus. We conclude that the benefits of the co-administration of vitamin E might be the results of antioxidant and anti-inflammatory effects of vitamin E which might be potentiating the antiseizure effects of RUFI and GABA-A modulating potential by ivermectin.

Drivers and evolution of acaricide resistance and multi-resistance in two Ecuador's subtropical livestock farming areas.

The management of cattle ticks, particularly Rhipicephalus microplus, poses a global challenge in subtropical regions like Ecuador due to its impact on meat and milk productivity, leading to economic losses. Misuse of acaricides has resulted in resistance and multi-resistance, diminishing their effectiveness. This study evaluated resistance to amitraz, alpha-cypermethrin, and ivermectin using the Larval Packet test, laboratory-reared tick larvae collected from cattle were tested. Data on farm management and tick control practices were gathered via a questionnaire in Northwest Pichincha and Quijos River Valley over two years. Resistance rates in the first year (2020-2021) were 67.21% for amitraz, 57.38% for ivermectin, and 67.21% for alpha-cypermethrin. One year later (2021-2022), resistance levels were 59.57% for amitraz, 57.45% for ivermectin, and 68.09% for alpha-cypermethrin, with multi-resistance rates at 67.21% and 65.96% respectively. No significant differences were found between years or locations. Analysis of larval survival data determined lethal doses for tested acaricides. The study emphasizes the association between the lack of acaricide rotation, the incorrect dosage, and the absence of non-chemical measures in tick management could be associated with the development of resistances in ticks. Likewise, this study promotes the need for collaborative efforts to improve control practices and maintain acaricide efficacy.

In Silico Comparative Analysis of Ivermectin and Nirmatrelvir Inhibitors Interacting with the SARS-CoV-2 Main Protease.

Exploring therapeutic options is crucial in the ongoing COVID-19 pandemic caused by SARS-CoV-2. Nirmatrelvir, which is a potent inhibitor that targets the SARS-CoV-2 Mpro, shows promise as an antiviral treatment. Additionally, Ivermectin, which is a broad-spectrum antiparasitic drug, has demonstrated effectiveness against the virus in laboratory settings. However, its clinical implications are still debated. Using computational methods, such as molecular docking and 100 ns molecular dynamics simulations, we investigated how Nirmatrelvir and Ivermectin interacted with SARS-CoV-2 Mpro(A). Calculations using density functional theory were instrumental in elucidating the behavior of isolated molecules, primarily by analyzing the frontier molecular orbitals. Our analysis revealed distinct binding patterns: Nirmatrelvir formed strong interactions with amino acids, like MET49, MET165, HIS41, HIS163, HIS164, PHE140, CYS145, GLU166, and ASN142, showing stable binding, with a root-mean-square deviation (RMSD) of around 2.0 Å. On the other hand, Ivermectin interacted with THR237, THR239, LEU271, LEU272, and LEU287, displaying an RMSD of 1.87 Å, indicating enduring interactions. Both ligands stabilized Mpro(A), with Ivermectin showing stability and persistent interactions despite forming fewer hydrogen bonds. These findings offer detailed insights into how Nirmatrelvir and Ivermectin bind to the SARS-CoV-2 main protease, providing valuable information for potential therapeutic strategies against COVID-19.