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1.
Molecules ; 29(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38611746

RESUMO

Spodoptera frugiperda, the fall armyworm (FAW), is a highly invasive polyphagous insect pest that is considered a source of severe economic losses to agricultural production. Currently, the majority of chemical insecticides pose tremendous threats to humans and animals besides insect resistance. Thus, there is an urgent need to develop new pest management strategies with more specificity, efficiency, and sustainability. Chitin-degrading enzymes, including chitinases, are promising agents which may contribute to FAW control. Chitinase-producing microorganisms are reported normally in bacteria and fungi. In the present study, Serratia marcescens was successfully isolated and identified from the larvae of Spodoptera frugiperda. The bacterial strain NRC408 displayed the highest chitinase enzyme activity of 250 units per milligram of protein. Subsequently, the chitinase gene was cloned and heterologously expressed in E. coli BL21 (DE3). Recombinant chitinase B was overproduced to 2.5-fold, driven by the T7 expression system. Recombinant chitinase B was evaluated for its efficacy as an insecticidal bioagent against S. frugiperda larvae, which induced significant alteration in subsequent developmental stages and conspicuous malformations. Additionally, our study highlights that in silico analyses of the anticipated protein encoded by the chitinase gene (ChiB) offered improved predictions for enzyme binding and catalytic activity. The effectiveness of (ChiB) against S. frugiperda was evaluated in laboratory and controlled field conditions. The results indicated significant mortality, disturbed development, different induced malformations, and a reduction in larval populations. Thus, the current study consequently recommends chitinase B for the first time to control FAW.


Assuntos
Quitinases , Inseticidas , Animais , Humanos , Quitinases/genética , Quitinases/farmacologia , Larva , Serratia marcescens/genética , Zea mays , Spodoptera , Escherichia coli , Clonagem Molecular , Produtos Agrícolas , Inseticidas/farmacologia
2.
Molecules ; 27(5)2022 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-35268671

RESUMO

Over recent decades, much attention has been given to imply the natural products in cancer therapy alone or in combination with other established procedures. Insects have a rich history in traditional medicine across the globe, which holds promise for the future of natural product drug discovery. Cecropins, peptides produced by insects, are components of a defense system against infections and are well known to exert antimicrobial and antitumor capabilities. The present study aimed to investigate, for the first time, the role of curcumin in enhancing the anticancer effect of Musca domestica larval hemolymph. Third larval instars of M. domestica were injected with curcumin and the hemolymph was picked at 4, 8, and 24 h post-curcumin injection. M. domestica cecropin A (MdCecA) was evaluated in control and injected larval hemolymphs. The cytotoxicity on breast cancer cell lines (MCF-7) and normal Vero cells was assessed to be comparable to control larval hemolymph. Curcumin-injected larval hemolymphs exhibited significant cytotoxicity with respect to the uninjected ones against MCF-7; however, Vero cells showed no cytotoxicity. The IC50 was 106 ± 2.9 and 388 ± 9.2 µg/mL for the hemolymphs of injected larvae at 4 and 8 h, respectively, while the control larval hemolymph revealed the IC50 of >500 µg/mL. For mechanistic anticancer evaluation, concentrations of 30, 60, and 100 µg/mL of curcumin-injected larval hemolymphs were examined. A significant G2/M cell cycle arrest was observed, confirming the anti-proliferative properties of hemolymphs over the tested concentrations. The MdCecA transcripts were significantly (p < 0.05) upregulated at 4 and 8 h post-injection, while a significant downregulation was observed after 24 h. Cecropin quantification by LC−MS revealed that MdCecA peptides have the highest expression in the hemolymph of the treated larvae at 8 h relative to the control group. The upregulation of cecropin expression at mRNA and protein levels may be attributed to the curcumin stimulation and linked to the increased cytotoxicity toward the cancer cell line. In conclusion, the results suggest that the apoptotic and anti-proliferative effects of M. domestica hemolymph on MCF-7 cells following the curcumin injection can be used as a natural candidate in future pharmaceutical industries.


Assuntos
Chlorocebus aethiops , Animais
3.
Molecules ; 27(19)2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36235123

RESUMO

Cardiotonic steroids (CTS) were first documented by ancient Egyptians more than 3000 years ago. Cardiotonic steroids are a group of steroid hormones that circulate in the blood of amphibians and toads and can also be extracted from natural products such as plants, herbs, and marines. It is well known that cardiotonic steroids reveal effects against congestive heart failure and atrial fibrillation; therefore, the term "cardiotonic" has been coined. Cardiotonic steroids are divided into two distinct groups: cardenolides (plant-derived) and bufadienolides (mainly of animal origin). Cardenolides have an unsaturated five-membered lactone ring attached to the steroid nucleus at position 17; bufadienolides have a doubly unsaturated six-membered lactone ring. Cancer is a leading cause of mortality in humans all over the world. In 2040, the global cancer load is expected to be 28.4 million cases, which would be a 47% increase from 2020. Moreover, viruses and inflammations also have a very nebative impact on human health and lead to mortality. In the current review, we focus on the chemistry, antiviral and anti-cancer activities of cardiotonic steroids from the naturally derived (toads) venom to combat these chronic devastating health problems. The databases of different research engines (Google Scholar, PubMed, Science Direct, and Sci-Finder) were screened using different combinations of the following terms: "cardiotonic steroids", "anti-inflammatory", "antiviral", "anticancer", "toad venom", "bufadienolides", and "poison chemical composition". Various cardiotonic steroids were isolated from diverse toad species and exhibited superior anti-inflammatory, anticancer, and antiviral activities in in vivo and in vitro models such as marinobufagenin, gammabufotalin, resibufogenin, and bufalin. These steroids are especially difficult to identify. However, several compounds and their bioactivities were identified by using different molecular and biotechnological techniques. Biotechnology is a new tool to fully or partially generate upscaled quantities of natural products, which are otherwise only available at trace amounts in organisms.


Assuntos
Produtos Biológicos , Bufanolídeos , Glicosídeos Cardíacos , Venenos , Animais , Antivirais , Bufanolídeos/química , Bufonidae , Cardenolídeos/química , Glicosídeos Cardíacos/farmacologia , Hormônios , Humanos , Lactonas
4.
J Appl Biomed ; 18(2-3): 80-86, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34907729

RESUMO

BACKGROUND: The liver is the main metabolic organ involved in disposal and detoxification of various molecules. Plantago psyllium L. seed has been reported to exert positive effects in some pathological conditions. The current study aims to assess the hepatoprotective effect of Plantago psyllium L. seed extract against carbon tetrachloride-induced hepatotoxicity. METHODS: Male albino Wistar rats were randomly divided into five groups of 10 rats each. Hepatotoxicity was induced by orally administered carbon tetrachloride (CCl4) for nine weeks with or without the different treatments which were utilized daily for the whole nine weeks. Serum and tissue samples were then withdrawn and different liver biomarkers were investigated. RESULTS: Treatment of rats with Psyllium seed ethanolic extract significantly alleviated the toxic effects of CCl4. This was evidenced by its ability to restore liver biomarkers levels. Moreover, treatment with Psyllium seed extract normalized levels of oxidative biomarkers such as lipid peroxidation, hepatic content of reduced glutathione and catalase activity, as well as the expression level of the inflammatory marker TNF-α. Histopathological examination reflected the protective effect of the extract on liver architecture and confirmed the observed biochemical data. CONCLUSIONS: The presented data demonstrates a potential hepatoprotective effect of Psyllium seed extract compared to the standard hepatoprotective drug silymarin. This effect can be attributed to the antioxidant and anti-inflammatory effects of Psyllium extract.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Plantaginaceae , Plantago , Psyllium , Animais , Antioxidantes/farmacologia , Tetracloreto de Carbono/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Masculino , Extratos Vegetais/farmacologia , Psyllium/farmacologia , Ratos , Ratos Wistar , Sementes
5.
Med Princ Pract ; 22(5): 458-63, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23635908

RESUMO

OBJECTIVES: To estimate the prevalence of illicit use of substances and identify the factors associated with illicit drug use among male students in the state-run Kuwait University and private universities in Kuwait. SUBJECTS AND METHODS: The study was a cross-sectional survey with a sample of 1,587 male students from both private universities (n = 869) and the public (n = 718) Kuwait University in Kuwait. A self-administered questionnaire was used to collect data. Overall lifetime prevalence of substance use was computed with 95% confidence interval. Logistic regression was used to identify the factors influencing substance use, which was adjusted for potential confounders. RESULTS: The total lifetime prevalence of illicit drug use was 14.4% and the most frequently used illicit substance was marijuana (11%). The substance use in general varied significantly (p ≤ 0.001) between private (18%) and public (10%) universities. Multivariate logistic regression model revealed that drug use was positively associated with age, poor academic performance, high family income, being an only child, divorced parents, and graduation from a private high school. CONCLUSION: Drug use among male university students in Kuwait was high and requires attention and appropriate intervention. The factors identified with drug use in this study could be utilized to develop appropriate public health policies and preventive measures that may improve the health status of the student population.


Assuntos
Drogas Ilícitas , Estudantes/estatística & dados numéricos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Universidades/estatística & dados numéricos , Adolescente , Adulto , Estudos Transversais , Humanos , Kuweit/epidemiologia , Masculino , Prevalência , Fatores Socioeconômicos , Adulto Jovem
6.
Pharmaceutics ; 12(11)2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33227988

RESUMO

The usage of insects as a sustainable and functional natural products resource is a new promise in complementary and alternative medicine. The present study aimed to investigate the ability of Musca domestica (housefly) larval hemolymph (insect blood) to display the enhanced in vitro antioxidant and cytotoxic effects. The oxidative stress (OS) was elicited by inducing lipopolysaccharides (LPS) treatment as an exogenous stressor. Determination of superoxide dismutase 1 (SOD1), glutathione (GSH), malondialdehyde (MDA) and total antioxidant capacity (TAC), and mRNA and protein expressions of SOD1, was investigated as confirmatory markers of oxidative stress induction. Cytotoxicity on cancerous MCF-7 and normal Vero cells were also evaluated using an MTT assay at 24 h post-injection. The injection of LPS induced a significant (p < 0.05) increase in SOD, GSH and TAC, whereas, the MDA was diminished. Hemolymph was collected from normal and treated larvae after 6, 12 and 24 h. The M. domestica superoxide dismutase (MdSOD1) transcripts were significantly (p < 0.05) upregulated 6 and 12 h post-treatment, while a significant downregulation was observed after 24 h. Western blot analysis showed that MdSOD1 was expressed in the hemolymph of the treated larvae with an increase of 1.2 folds at 6 and 12 h and 1.6 folds at 24 h relative to the control group. LPS-treated larval hemolymphs exhibited significant cytotoxicity with respect to the untreated ones against MCF-7 while Vero cells showed no cytotoxicity for both hemolymphs. The DPPH free radical scavenging activity was examined and a significant antioxidant potential potency was observed at 6 h (50% maximal inhibitory concentration (IC50): 63.3 ± 3.51 µg/mL) when compared to the control M. domestica larval hemolymph (IC50: 611.7 ± 10.41 µg/mL). Taken together, M. domestica larval hemolymph exhibited enhanced antioxidant and consequently increased cytotoxic capacities under stressed conditions.

7.
J Med Entomol ; 57(6): 1686-1693, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-32785585

RESUMO

Forensic entomologists rely on laboratory growth data to estimate the time of colonization on human remains thus extrapolating a minimum postmortem interval (PMI) if assumptions are satisfied. The flesh fly Blaesoxipha plinthopyga (Wiedemann) is one species that occurs in casework in Idaho, Texas, and central California. Because of the few laboratory studies on the development of this fly, the following study was conducted to determine if different substrates impact immature development of the species. In this study, flies were reared on different substrates that are likely to be encountered at indoor and outdoor scenes (Wet Sand, Dry Sand, Clothes [Polyester fibers], and Carpet [Polypropylene fibers]) to determine the influence of substrate on larval, intrapuparial, and total immature development times at 25°C, 50% RH, and 14:10 (L:D) h cycle. The results revealed that substrate significantly affected minimum immature development times without affecting the sexes differently; though a female bias in sex ratio was observed consistently. Average minimum larval developmental times were 160-179 h with a significantly faster development in Carpet than in Clothes. Similarly, average minimum intrapuparial developmental times were 331-352 h; fastest on Carpet and the slowest in Dry Sand. For this species, it may be important to consider the substrates encountered at a death scene as they may affect the development of B. plinthopyga (Wiedemann) in casework by up to 29 h at 25°C and 50% humidity. These effects will also be important to consider when planning future development studies with the species.


Assuntos
Entomologia Forense , Sarcofagídeos/crescimento & desenvolvimento , Animais , Vestuário , Dieta , Pisos e Cobertura de Pisos , Larva/crescimento & desenvolvimento , Areia
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