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1.
Int J Mol Sci ; 25(10)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38791600

RESUMO

Lead (Pb) is a common pollutant that is not biodegradable and gravely endangers the environment and human health. Annona squamosa fruit has a wide range of medicinal uses owing to its phytochemical constituents. This study evaluated the effect of treatment with A. squamosa fruit extract (ASFE) on testicular toxicity induced in male rats by lead acetate. The metal-chelating capacity and phytochemical composition of ASFE were determined. The LD50 of ASFE was evaluated by probit analysis. Molecular docking simulations were performed using Auto Dock Vina. Forty male Sprague Dawley rats were equally divided into the following groups: Gp1, a negative control group; Gp2, given ASFE (350 mg/kg body weight (b. wt.)) (1/10 of LD50); Gp3, given lead acetate (PbAc) solution (100 mg/kg b. wt.); and Gp4, given PbAc as in Gp3 and ASFE as in Gp2. All treatments were given by oro-gastric intubation daily for 30 days. Body weight changes, spermatological parameters, reproductive hormone levels, oxidative stress parameters, and inflammatory biomarkers were evaluated, and molecular and histopathological investigations were performed. The results showed that ASFE had promising metal-chelating activity and phytochemical composition. The LD50 of ASFE was 3500 mg/kg b. wt. The docking analysis showed that quercetin demonstrated a high binding affinity for JAK-1 and STAT-3 proteins, and this could make it a more promising candidate for targeting the JAK-1/STAT-3 pathway than others. The rats given lead acetate had defective testicular tissues, with altered molecular, biochemical, and histological features, as well as impaired spermatological characteristics. Treatment with ASFE led to a significant mitigation of these dysfunctions and modulated the JAK-1/STAT-3/SOCS-1 axis in the rats.


Assuntos
Annona , Frutas , Janus Quinase 1 , Simulação de Acoplamento Molecular , Compostos Organometálicos , Extratos Vegetais , Ratos Sprague-Dawley , Fator de Transcrição STAT3 , Transdução de Sinais , Testículo , Animais , Masculino , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Fator de Transcrição STAT3/metabolismo , Ratos , Annona/química , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testículo/patologia , Frutas/química , Transdução de Sinais/efeitos dos fármacos , Janus Quinase 1/metabolismo , Estresse Oxidativo/efeitos dos fármacos
2.
Biochem Biophys Res Commun ; 669: 54-60, 2023 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-37267860

RESUMO

Polymorphisms in Plasmodium falciparum chloroquine resistance transporter (or PfCRT) were shown to be causative of decreased sensitivity to diverse quinoline-based antimalarials. In this report we describe the identification of a post-translational variant of PfCRT using highly characterized antibodies raised against its N- and C-terminal cytoplasmic domains (e.g., 58 and 26 amino acids, respectively). Western blot analyses of P. falciparum protein extracts with anti N-PfCRT antiserum revealed two polypeptides with apparent molecular masses of 52 kDa and 42 kDa, relative to the calculated molecular mass of PfCRT of 48.7 kDa. The 52 kDa polypeptide was detectable with anti C-PfCRT antiserum, only after alkaline phosphatase treatment of P. falciparum extracts. Detailed epitope mapping of anti N- and C-PfCRT antisera revealed epitopes covering two previously identified phosphorylation sites, Ser411 and Thr416, whereby substitution of these residues with Asp amino acid, to mimic phosphorylated residues, dramatically inhibited anti C-PfCRT binding. Consistently, alkaline phosphatase treatment of P. falciparum extract unmasked the binding of anti C-PfCRT to the 52 kDa polypeptide, suggesting that the 52 kDa but not 42 kDa polypeptide is phosphorylated at its C-terminal Ser411 and Thr416. Interestingly, Pfcrt expressed in HEK-293F human kidney cells showed the same reactive polypeptides with anti N- and C-PfCRT antisera, consistent with PfCRT origin of the two polypeptides (e.g., 42 kDa and 52 kDa), but lacking PfCRT phosphorylation at its C-terminal. Immunohistochemical staining of late trophozoite-infected erythrocytes with anti N-or C-PfCRT antisera showed both polypeptides are localized to the parasite's digestive vacuole. Moreover, both polypeptides are detected in chloroquine-susceptible and -resistant strains of P. falciparum. This is the first report describing a post-translationally modified variant of PfCRT. The physiologic role of the 52 kDa phosphorylated PfCRT in P. falciparum remains to be determined.


Assuntos
Antimaláricos , Malária Falciparum , Humanos , Epitopos/metabolismo , Fosfatase Alcalina/metabolismo , Plasmodium falciparum/metabolismo , Antimaláricos/farmacologia , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Anticorpos/metabolismo , Soros Imunes , Resistência a Medicamentos
3.
Malar J ; 22(1): 53, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36782234

RESUMO

BACKGROUND: Livelihood activities and human movements participate in the epidemiology of vector-borne diseases and influence malaria risk in elimination settings. In Saudi Arabia, where malaria transmission intensity varies geographically, it is vital to understand the components driving transmission within specific areas. In addition, shared social, behavioural, and occupational characteristics within communities may provoke the risk of malaria infection. This study aims to understand the relationship between human mobility, livelihood activities, and the risk of malaria infection in the border region of Jazan to facilitate further strategic malaria interventions. In addition, the study will complement and reinforce the existing efforts to eliminate malaria on the Saudi and Yemen border by providing a deeper understanding of human movement and livelihood activities. METHODS: An unmatched case-control study was conducted. A total of 261 participants were recruited for the study, including 81 cases of confirmed malaria through rapid diagnostic tests (RDTs) and microscopy and 180 controls in the Baish Governorate in Jazan Provinces, Saudi Arabia. Individuals who received malaria tests were interviewed regarding their livelihood activities and recent movement (travel history). A questionnaire was administered, and the data was captured electronically. STATA software version 16 was used to analyse the data. Bivariate and multivariate analyses were conducted to determine if engaging in agricultural activities such as farming and animal husbandry, recent travel history outside of the home village within the last 30 days and participating in spiritual gatherings were related to malaria infection status. RESULTS: A logistical regression model was used to investigate components associated with malaria infection. After adjusting several confounding factors, individuals who reported travelling away from their home village in the last 30 days OR 11.5 (95% CI 4.43-29.9), and those who attended a seasonal night spiritual gathering OR 3.04 (95% CI 1.10-8.42), involved in animal husbandry OR 2.52 (95% CI 1.10-5.82), and identified as male OR 4.57 (95% CI 1.43-14.7), were more likely to test positive for malaria infection. CONCLUSION: Human movement and livelihood activities, especially at nighttime, should be considered malaria risk factors in malaria elimination settings, mainly when the targeted area is limited to a confined borderland area.


Assuntos
Malária , Animais , Humanos , Masculino , Estudos de Casos e Controles , Malária/prevenção & controle , Fatores de Risco , Viagem , Criação de Animais Domésticos
4.
Biochem Biophys Res Commun ; 557: 261-266, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33894412

RESUMO

The Plasmodium falciparum chloroquine resistance transporter (PfCRT) is a phospho-protein with three identified phosphorylation sites (Ser33, Ser411 and Thr416) at its cytosolic N- and C-termini. In this study, we report on the characterization of PfCRT anti-serum and show the presence of three epitope-specific immunoglobulin (IgG) pools (i.e., IgG-P1, P2, and P3), each recognizing a different epitope in PfCRT cytoplasmic C-terminal. IgG-P2 bound the heptapeptide sequence (408NEDSEGE414), including Ser411. The effect of Ser411 phosphorylation on the binding specificity of IgG-P2 was confirmed using heptapeptides and full-length PfCRT with substitutions of Ser411 with aspartic acid (phospho-serine mimic) and alanine residues. Moreover, using purified IgG-P2, we show the presence of PfCRT homodimer that has un-phosphorylated Ser411 and migrates with an apparent molecular mass of 90 kDa on SDS-PAGE. In addition, parasite lysates showed PfCRT to be more phosphorylated at Ser411 in CQ-sensitive (3D7) than CQ-resistant (Dd2-H) strains of P. falciparum. Taken together, the findings of this study suggest a role for Ser411 phosphorylation in PfCRT structure-function.


Assuntos
Imunoglobulina G/metabolismo , Malária Falciparum/parasitologia , Proteínas de Membrana Transportadoras/metabolismo , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo , Antimaláricos/farmacologia , Cloroquina/farmacologia , Dimerização , Epitopos/metabolismo , Células HEK293 , Humanos , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Mutação , Fosforilação , Ligação Proteica , Proteínas Recombinantes
5.
Anal Chem ; 91(3): 2216-2223, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30601655

RESUMO

Despite global efforts aimed at its elimination, malaria is still a significant health concern in many countries across the world. The disease is caused by blood-borne parasites, Plasmodium species, and is transmitted by female Anopheles mosquitoes and presents with generic febrile symptoms that are challenging to diagnose clinically. To adequately tackle this issue, an effective detection method is required for screening potential malaria patients for infection. To this day, the gold standard for malaria detection remains basic light microscopy of Giemsa-stained patient blood smears to first enable detection and manual counting to determine the parasite density by a microscopist. While effective at detecting parasites, this method requires both significant time and skilled personnel. As an alternate approach, we propose a new malaria detection method that we call third-harmonic generation image scanning cytometry (THGISC) based on the combination of third-harmonic generation imaging, high-speed motorized scanning, and automated software processing. Third-harmonic generation (THG) is a nonlinear optical process in which the frequency of incident photons is tripled within the sample material. We have previously demonstrated that hemozoin, a metabolic byproduct of the malaria parasite, presents a significant THG signal. We now present a practical approach that uses the selectivity of this contrast mechanism to perform label-free image scanning cytometry of patient blood smears for automated malaria detection. In this work, we applied this technique to lab-cultured parasites and parasites in whole blood obtained from malaria patients. We also compared its effectiveness to parasite counts obtained by classical methods. The ability to easily and rapidly determine parasitemia by THG offers potential not only for the easy confirmation of malaria diagnoses following symptoms, but also the tracking of treatment progress in existing patients, potentially allowing physicians to adjust medication and dosage for each individual.


Assuntos
Citometria por Imagem/métodos , Malária Falciparum/diagnóstico , Plasmodium falciparum/isolamento & purificação , Eritrócitos/química , Hemeproteínas/química , Hemoglobinas/química , Humanos , Processamento de Imagem Assistida por Computador , Estudo de Prova de Conceito , Esquizontes/isolamento & purificação , Software , Trofozoítos/isolamento & purificação
6.
Acta Parasitol ; 69(2): 1267-1274, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38753102

RESUMO

PURPOSE: This study aimed to develop and evaluate a lateral flow card for the detection of active Schistosoma haematobium infection. METHODS: In order to prepare the immunochromatography lateral flow strip (ICLFS), antibodies purified from schistosomiasis were conjugated passively with gold nanoparticles using a potassium carbonate buffer. RESULTS: The novel ICLFS was able to correctly identify 64 out of 67 samples of schistosomiasis, 6 out of 90 samples of other parasites, and 0 out of 27 control samples. Sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) were 95.5%, 93.3%, 90%, and 91.4% respectively. Comparatively, the sensitivity, specificity, NPV, and PPV of sandwich enzyme-linked immunosorbent assays (ELISA) conjugated with gold nanoparticles (AuNPs) were 91.1%, 88.8%, 85.9%, and 84.4% respectively. The increased sensitivity and specificity of ICLFS produced superior results to those of sandwich ELISA. CONCLUSION: In conclusion, ICLFS is more beneficial and precise than sandwich ELISA for detection of S. haematobium infection at early stage.


Assuntos
Antígenos de Helmintos , Cromatografia de Afinidade , Ouro , Nanopartículas Metálicas , Schistosoma haematobium , Esquistossomose Urinária , Sensibilidade e Especificidade , Ouro/química , Humanos , Schistosoma haematobium/imunologia , Nanopartículas Metálicas/química , Animais , Esquistossomose Urinária/diagnóstico , Cromatografia de Afinidade/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Anticorpos Anti-Helmínticos/sangue , Fitas Reagentes
7.
Pathogens ; 11(7)2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35890042

RESUMO

Background:Toxoplasma gondii (T. gondii) is an opportunistic parasite that causes serious diseases in humans, particularly immunocompromised individuals and pregnant women. To date, there are limited numbers of therapeutics for chronic toxoplasmosis which necessitate the discovery of effective and safe therapeutics. In the present study, we aimed to evaluate the antitoxoplasmosis potential of ginger extract in mice with experimentally induced chronic toxoplasmosis. Results: Treatment with ginger extract significantly reduced cysts count in the brains of T. gondii-infected mice with a marked alleviation of edema and inflammation, and a reversal of neuronal injury. Moreover, ginger extract treatment reduced inflammation in liver and lungs and protected hepatocytes from infection-induced degeneration. Consistently, apoptosis was significantly mitigated in the brains of ginger extract-treated mice compared to infected untreated animals or spiramycin-treated animals. Methods: Four groups of Swiss albino mice (10 mice each) were used. The first group was not infected, whereas 3 groups were infected with Me49 T. gondii strains. One infected group remained untreated (infected untreated), whereas the other two infected groups were treated with either ginger extract (250 mg/kg) or spiramycin (positive control; 100 mg/kg), respectively. The therapeutic potential of ginger extract was evaluated by calculation of the parasite burden in infected animals, and examination of the infected tissues for reduced pathologic changes. Conclusions: Our results showed for the first time that ginger extract exhibited marked therapeutic effects in mice with chronic T. gondii infection which indicates that it can be used as a safe and effective treatment for chronic toxoplasmosis.

8.
Pathogens ; 11(12)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36558781

RESUMO

Mango hopper (Amritodus atkinsoni Lethierry) causes devastations in the early vegetative stage of the mango crop. The classical management of mango hopper is with systemic insecticides but their overuse has caused environmental pollution. Here, we have evaluated the entomopathogenic role of Clonostachys rosea through bioassay and optimized media for its large-scale culturing. The current study reveals the potentiality of C. rosea as entomopathogenic on A. atkinsoni. Initially, morphological and molecular characterization was used to validate local isolates' identity as C. rosea. Further, we have evaluated the entomopathogenic role of C. rosea through a bioassay, where the highest mean mortality in A. atkinsoni was observed at a treatment concentration of 3 × 108 conidia/mL, with 96.67% mortality after 168 h of infection. This work also provides insight into the laboratory-based media standardization for C. rosea, resulting in oatmeal agar media and broth as the most suitable artificial media, and 20 °C temperature for its mass culture. Thus, C. rosea is a novo-entomopathogenic fungus on A. atkinsoni and has a high potency to be included in the management of mango hopper pests.

9.
J Inorg Biochem ; 194: 214-222, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30877896

RESUMO

The malaria parasite, Plasmodium spp., produces hemozoin (Hz) crystals as a by-product of hemoglobin digestion. Purification methods used to remove host or parasite products adsorbed on Hz surface lead to variable and undetermined residues. This compositional variation likely accounts for the assortment of contradictory results in studies of Hz's biomineralization, immunomodulating properties, and the mechanism of action of some antimalarials. In this work, we study the surface of Hz cleaned with two methods, both reported in the literature, one stricter than the other. We find that biomolecules are adsorbed on Hz treated with either method, they bind through carboxylate groups, and may be present within Hz structure. Their composition and amount depend on the washing protocol, which also introduces contaminants. This finding led us to question the concept of "pure" Hz, and to propose x-ray photoelectron spectroscopy (XPS) and matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) as characterization tools to assess surface contamination prior to further work on Hz crystals.


Assuntos
Hemeproteínas/química , Adsorção , Aminoácidos/química , Cristalização , Membrana Eritrocítica/química , Hemeproteínas/isolamento & purificação , Espectroscopia Fotoeletrônica , Plasmodium falciparum , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Propriedades de Superfície
10.
J Inorg Biochem ; 200: 110808, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31487576

RESUMO

In malaria, Plasmodium parasites produce hemozoin (Hz) as a route to detoxify free heme released from the catabolism of hemoglobin. Hz isolated from the parasites is encapsulated in an organic layer constituted by parasite and host components. This organic coating may play a role in Hz formation and in the immunomodulatory properties attributed to Hz, and they may influence the mode of action of antimalarials that block Hz formation. In this work, we analyze the organic layer adhered to Hz, and find Na, Cl, Si, Ca and P present, in addition to organic material. Our results suggest that Na, Cl, and P adsorb during Hz release from the red blood cells, while Si and Ca derive from components present during Hz biomineralization within the digestive vacuole of the parasite. Overall, we show that inorganic elements associated with Hz surface provide insights into the biological functions of Plasmodium parasites.


Assuntos
Eritrócitos , Hemeproteínas/metabolismo , Plasmodium chabaudi/metabolismo , Plasmodium falciparum/metabolismo , Animais , Eritrócitos/metabolismo , Eritrócitos/parasitologia , Humanos , Íons/farmacologia , Camundongos
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