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J Ethnopharmacol ; : 113647, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33271242


ETHNOPHARMACOLOGICAL RELEVANCE: Scurrula ferruginea (Jack) Danser (locally known as 'Dedalu' or 'dian nan ji sheng' in Malaysia and China) is a hemi-parasitic shrub that is widely used as herbal medicine to treat inflammation, rheumatism, and stroke. However, the scientific basis of its anti-inflammatory function and mechanism remain to be proven. AIM OF THE STUDY: To evaluate the anti-inflammatory activity as well as the preliminary mechanism of S. ferruginea parasitizing on Tecoma stans. MATERIALS AND METHODS: The anti-inflammatory capability of freeze-dried stem aqueous extract was assessed via inhibition of inflammatory cytokines interleukin- (IL-) 1ß, IL-6, IL-10, and tumor necrosis factor-alpha (TNF-α) production in lipopolysaccharide (LPS) and interferon-γ (IFN-γ) stimulated RAW 264.7 macrophages. The underlying anti-inflammatory mechanism was deciphered through reverse transcriptase and real time quantitative polymerase chain reactions (RT-PCR and qPCR) for inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), IL-1ß, and TNF-α mRNA expression. RESULTS: The results exhibited that aqueous extract of freeze-dried S. ferruginea stem sample concentration-dependently inhibited IL-1ß protein production along with the down regulation of iNOS and IL-1ß mRNA expression. Moreover, it significantly suppressed the protein release of IL-6 and IL-10 in a concentration-dependent manner. However, it slightly reduced TNF-α at higher sample concentration (250 µg/mL) without affecting the mRNA expression levels of COX-2 and TNF-α. CONCLUSIONS: This study suggests that S. ferruginea parasitizing on Tecoma stans exerted anti-inflammatory capability attributed to inhibition of iNOS and IL-1ß mRNA expression, NO creation, IL-1ß, IL-6, IL-10, and TNF-α protein production, indicating this plant might be a useful plant-derived candidate against inflammation.

J Biotechnol ; 263: 21-29, 2017 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-29017848


Cotton leaf curl disease (CLCuD), a major factor resulting in the enormous yield losses in cotton crop, is caused by a distinct monopartite begomovirus in association with Cotton leaf curl Multan betasatellite (CLCuMB). Micro(mi)RNAs are known to regulate gene expression in eukaryotes, including antiviral defense in plants. In a previous study, we had computationally identified a set of cotton miRNAs, which were shown to have potential targets in the genomes of Cotton leaf curl Multan virus (CLCuMuV) and CLCuMB at multiple loci. In the current study, effect of Gossypium arboreum-encoded miRNAs on the genome of CLCuMuV and CLCuMB was investigated in planta. Two computationally predicted cotton-encoded miRNAs (miR398 and miR2950) that showed potential to bind multiple Open Reading Frames (ORFs; C1, C4, V1, and non- coding intergenic region) of CLCuMuV, and (ßC1) of CLCuMB were selected. Functional validation of miR398 and miR2950 was done by overexpression approach in G. hirsutum var. HS6. A total of ten in vitro cotton plants were generated from independent events and subjected to biological and molecular analyses. Presence of the respective Precursor (pre)-miRNA was confirmed through PCR and Southern blotting, and their expression level was assessed by semi quantitative RT-PCR, Real Time quantitative PCR and northern hybridization in the PCR-positive lines. Southern hybridization revealed 2-4 copy integration of T-DNA in the genome of the transformed lines. Remarkably, expression of pre-miRNAs was shown up to 5.8-fold higher in the transgenic (T0) lines as revealed by Real Time PCR. The virus resistance was monitored following inoculation of the transgenic cotton lines with viruliferous whitefly (Bemisia tabaci) insect vector. After inoculation, four of the transgenic lines remained apparently symptom free. While a very low titre of viral DNA could be detected by Rolling circle amplification, betasatellite responsible for symptom induction could not be detected in any of the healthy looking transgenic lines. In this study for the first time, efficacy of the host (G. arboreum)-encoded miRNAs against CLCuD symptoms was experimentally demonstrated through overexpression of miR398 and miR2950 in G. hirsutum var. HS6 plants. Computational prediction of miRNAs targeting virus genome and their subsequent implication in translational inhibition or cleavage based suppression of viral mRNA via overexpression could help in generating virus resistant plants.

Begomovirus/metabolismo , Gossypium , MicroRNAs/metabolismo , Doenças das Plantas , Plantas Geneticamente Modificadas , RNA de Plantas/metabolismo , DNA Viral/análise , Genoma Viral , Gossypium/genética , Gossypium/virologia , MicroRNAs/genética , Doenças das Plantas/genética , Doenças das Plantas/prevenção & controle , Doenças das Plantas/virologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/virologia , RNA de Plantas/genética
Recent Pat Biotechnol ; 8(1): 102-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-22642822


Artemisinin, a potent antimalarial natural products isolated from aerial parts of Artemisia annua L. Many patents have been reported that the demand for artemisinin is exponentially increasing year after year due to increased incidences of drug resistant malaria throughout the world. Leaf explants were used frequently as target tissue to generate transgenic of Artemisia. annua L. However, obtaining a large number of transgenic lines through out the year is a laborious and delicate process. To circumvent this, we have developed a highly efficient leaf explant based Agrobacterium mediated transformation of A. annua L. plant. The gus gene was used as screenable marker to assess and optimize the performance of T-DNA delivery. The age of explant, kind of bacterial inoculation, suspension duration, infection times and co-culture conditions were optimized. The co-culture was carried out with Agrobacterium tumefaciens strain EHA105 under desiccation condition in the dark at 25-28 0C for 2-4 days. Complete analysis of transgene insertion demonstrated that the optimized method of transformation from leaf explants of A. annua L. was efficient and highly reproducible.

Agrobacterium/metabolismo , Artemisia annua/metabolismo , Agrobacterium/genética , Artemisia annua/citologia , Técnicas de Cocultura , Glucuronidase/genética , Glucuronidase/metabolismo , Folhas de Planta/citologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Brotos de Planta/citologia , Plasmídeos/genética , Plasmídeos/metabolismo , Transformação Genética