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1.
Pest Manag Sci ; 78(1): 134-142, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34453868

RESUMO

BACKGROUND: Itol A, extracted from Itoa orientalis Hemsl. (Flacourtiaceae), possesses bioactivity on Spodoptera litura (Lepidoptera: Noctuidae) and Nilaparvata lugens (Stål) (Hemiptera: Delphacidae). Our previous study showed that the effects on Spodoptera frugiperda, a destructive pest found worldwide, were similar to those of fenoxycarb (FC), a juvenile hormone analog. Thus, we speculate that itol A could have growth-regulating effects. The current work explored juvenile hormone (JH) levels and mRNA levels of crucial JH signaling pathway enzyme genes in S. frugiperda larvae treated with itol A and FC. RESULTS: Itol A caused severe growth obstacles in S. frugiperda, extended the larval duration and reduced the mean worm weight and body length rates. Three and 7 days after exposure to a sublethal concentration of itol A (500 mg L-1 ), the JH level of the larvae significantly decreased by 36.59% and 22.70%, respectively. qPCR inferred that the mRNA expression levels of crucial JH metabolism enzymes (SfJHE and SfJHEH) significantly increased by 6.58-fold and 2.12-fold, respectively, relative to the control group 3 days after treatment. CONCLUSIONS: Itol A adversely affects the development of S. frugiperda. We propose that this effect was caused by decreasing JH levels and disrupting the JH signaling pathway via mediating its synthetic and metabolic crucial enzymes. © 2021 Society of Chemical Industry.


Assuntos
Hemípteros , Mariposas , Animais , Hormônios Juvenis/farmacologia , Larva , Spodoptera/genética
2.
P R Health Sci J ; 21(4): 323-8, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12572240

RESUMO

BACKGROUND: Plant materials represent promising sources of anti-cancer agents. We developed and tested a novel extract from the ubiquitous plant Convolvulus arvensis. MATERIALS AND METHODS: Convolvulus arvensis components were extracted in boiling water, and small molecules were removed by high-pressure filtration. The extract's biological activity was assessed by measuring its effects on S-180 fibrosarcoma growth in Kun Ming mice and on heparin-induced angiogenesis in chick embryos. We also examined the extract's effects on lymphocytes ex vivo and tumor cell growth in vitro. RESULTS: The extract (primarily proteins and polysaccharides) inhibited tumor growth in a dose-dependent fashion when administered orally. At the highest dose tested, 200 mg/kg/day, tumor growth was inhibited by roughly seventy percent. Subcutaneous or intraperitoneal administration at 50 mg/kg/day also inhibited tumor growth by over seventy percent. The extract's acute LD50 in Kun Ming mice was 500 mg/kg/day when injected, indicating that tumor growth inhibition occurred at non-toxic doses. It inhibited angiogenesis in chick embryos, improved lymphocyte survival ex vivo, and enhanced yeast phagocytosis, but did not kill tumor cells in culture. CONCLUSION: High molecular mass extract deserves further study as an anti-cancer agent.


Assuntos
Convolvulus , Neoplasias/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Fitoterapia , Preparações de Plantas/uso terapêutico , Animais , Células Cultivadas , Humanos , Linfócitos/efeitos dos fármacos , Camundongos , Peso Molecular , Neoplasias/patologia
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