Optimization of ultrasound-assisted extraction of Imperata cylindrica polysaccharides and evaluation of its anti-oxidant and amelioration of uric acid stimulated cell apoptosis.

An efficient, cost-effective and environmentally friendly ultrasound-assisted hot water method for Imperata cylindrica polysaccharide (ICPs) extraction was developed. According to the response surface results, the optimal ultrasonic time was 85 min, ultrasonic power was 192.75 W, temperature was 90.74 °C, liquid-solid ratio was 26.1, and polysaccharide yield was 28.50 %. The polysaccharide mainly consisted of arabinose (Ara), galactose (Gal), and glucose (Glc), with a molecular weight of 62.3 kDa. Ultrasound-assisted extraction of Imperata cylindrica polysaccharide (UICP) exhibited stronger anti-oxidant activity and ability to ameliorate cellular damage due to uric acid stimulation compared with traditional hot water extraction of Imperata cylindrica polysaccharide (ICPC-b). It also exhibited higher thermal stability, indicating its potential value for applications in the food industry.

Structural analysis and attenuates hyperuricemic nephropathy of dextran from the Imperata cylindrica Beauv. var. major (Nees) C. E. Hubb.

ICPC-a was from the Imperata cylindrica with a molecular weight of 45 kDa, which was composed of α-D-1,3-Glcp and α-D-1,6-Glcp. The ICPC-a showed thermal stability, maintaining its structural integrity up to 220°C. X-ray diffraction analysis confirmed its amorphous nature, while scanning electron microscopy revealed a layered morphology. ICPC-a significantly ameliorated uric acid stimulation-induced HK-2 cell injury and apoptosis and reduced uric acid levels in mice with hyperuricemic nephropathy. ICPC-a protected against renal injury by inhibiting lipid peroxidation levels, increasing antioxidant damage and defense levels, inhibiting secretion of pro-inflammatory factors, regulating purine metabolism, PI3K-Akt signaling pathway, NF-κB signaling pathway, inflammatory bowel disease, mTOR signaling pathway, and MAPK signaling pathway. These findings indicate that ICPC-a is a promising natural substance with multiple targets, multiple pathways of action, and without toxicity, making it a valuable subject for further research and development.

The Memory of Rice Response to Spaceflight Stress: From the Perspective of Metabolomics and Proteomics.

The stress response of plants to spaceflight has been confirmed in contemporary plants, and plants retained the memory of spaceflight through methylation reaction. However, how the progeny plants adapt to this cross-generational stress memory was rarely reported. Here, we used the ShiJian-10 retractable satellite carrying Dongnong416 rice seeds for a 12.5-day on-orbit flight and planted the F2 generation after returning to the ground. We evaluated the agronomic traits of the F2 generation plants and found that the F2 generation plants had no significant differences in plant height and number of tillers. Next, the redox state in F2 plants was evaluated, and it was found that the spaceflight broke the redox state of the F2 generation rice. In order to further illustrate the stress response caused by this redox state imbalance, we conducted proteomics and metabolomics analysis. Proteomics results showed that the redox process in F2 rice interacts with signal transduction, stress response, and other pathways, causing genome instability in the plant, leading to transcription, post-transcriptional modification, protein synthesis, protein modification, and degradation processes were suppressed. The metabolomics results showed that the metabolism of the F2 generation plants was reshaped. These metabolic pathways mainly included amino acid metabolism, sugar metabolism, cofactor and vitamin metabolism, purine metabolism, phenylpropane biosynthesis, and flavonoid metabolism. These metabolic pathways constituted a new metabolic network. This study confirmed that spaceflight affected the metabolic changes in offspring rice, which would help better understand the adaptation mechanism of plants to the space environment.

Effects of simulated digestion on black chokeberry (Aronia melanocarpa (Michx.) Elliot) anthocyanins and intestinal flora.

In this study, the changes of anthocyanin content, total phenols, antioxidant capacity, microbiota composition before and after digestion and intestine fermentation in stomach and intestine were studied. The results indicated that after simulated gastrointestinal digestion, compared with the original sample, the total phenol content and anthocyanin content of intestinal digestion group for 2 h (ID 2 group) decreased by 53.64% and 70.45%, respectively, DPPH inhibition rate was 32.75% and T-AOC values of the extracts decreased to 62.89U/mg. The anthocyanins were identified to be composed of cyanidin-3-arabinoside, cyanidin-3-galactoside, cyanidin-3-xyloside, and cyanidin-3-glucoside. Black Chokeberry (Aronia melanocarpa (Michx.) Elliot) anthocyanins significantly increased the relative richness of Bacteroides, promoted the growth of Bifidobacterium, Blautia, Faecalibacterium, and inhibited the growth of Prevotella, Megamonas, Escherichia/Shigella, etc. Anthocyanins have a positive regulatory effect on intestinal flora. These studies also provide essential information for the development of anthocyanin related health care products and drug products.

Anthocyanins from Aronia melanocarpa Induce Apoptosis in Caco-2 Cells through Wnt/ß-Catenin Signaling Pathway.

Colorectal cancer (CRC) is one of the most common malignant tumors in the world. In this study, the Caco-2 in vitro cell model was used to study the effect and mechanism of Aronia melanocarpa (Michx.) Elliott anthocyanins (AMA) on colon cancer. The experimental results showed that the binding energy of anthocyanins on ß-catenin was in the range of -5.92 to 4.95 kcal/mol, with good low energy parameters and binding positions. AMA can inhibit cell proliferation and cause cell cycle arrest. RT-PCR and Western blot results showed that AMA can reduce cytoplasmic ß-catenin and inhibit the expression of related proteins in Wnt/ß-catenin signaling pathway. This study revealed the AMA inhibitory effect and mechanism of malignant biological behavior of Caco-2 cells, in order to provide theoretical basis for the prevention and treatment of colon cancer by Aronia melanocarpa (Michx.) Elliott.

Regulation of aureofuscin production by the PAS-LuxR family regulator AurJ3M.

aurJ3M(GenBank:EU697915.1), a 579 bp gene, whose deduced product (192 amino acid) was found to have amino acid sequence homology with some bacterial regulatory proteins. Computer-assisted analysis showed that AurJ3M is PAS-LuxR family regulatory protein, it combines a PAS domain with a helix-turn-helix (HTH) motif of the LuxR type. Gene deletion of aurJ3M from the S.aureofuscus SYAU0709 through gene replacement with the apramycin resistance gene aac (3) IV and the DNA fragment of the replication initiation site sequence OriT resulted in complete loss of aureofuscin production, indicating that AurJ3M is a positive regulator during the aureofuscin biosynthesis. Gene expression analyses in S.aureofuscus SYAU0709 and S.aureofuscus ΔaurJ3M by reverse transcriptase PCR (RT-PCR) indicated there no transcripts for the genes B、C、G、F、S0、S1、D in S.aureofuscus ΔaurJ3M, maintains some transcription of these genes although the levels is low. Transcription was also significantly reduced for gene A, and no difference in the transcription pattern was observed for the genes R、E and H, a similar transcription pattern was also observed for AurJ3M, A and B showed a different transcription pattern, while transcription of gene A in S.aureofuscus ΔaurJ3M when compared to the parental strain, no transcripts could be detected for gene B in the mutant; This result indicates that the deletion of aurJ3M gene doesn't have a polar effect on the transcription of genes located downstream from aurJ3M. In the ΔaurJ3M knockout mutant, except for the transcription of E、H、M and R, the transcription of other genes in the cluster was down-regulated, HPLC shows there no secondary metabolites was produced,aurJ3M has a pathway-specific regulation effect on the biosynthesis of aureofuscin. Aureofuscin had broad application prospects in food preservation, and enriched the resource pool of anti-fungal antibiotics of tetraphenyl macrolide in China.

Fibroblasts weaken the anti-tumor effect of gefitinib on co-cultured non-small cell lung cancer cells.

BACKGROUND: Non-small cell lung cancer (NSCLC) is the most common lung malignancy worldwide. The metastatic potential of NSCLC cells has been shown to be associated with the tumor microenvironment, which consists of tumor cells, stroma, blood vessels, immune infiltrates and the extracellular matrix. Fibroblasts can produce numerous extracellular matrix molecules and growth factors. Gefitinib has been evaluated as a first-line treatment in selected patients, and it has shown favorable efficacy especially in NSCLC, but it is not effective for everyone. METHODS: In this study, we examined the antitumor activity of gefitinib on lung fibroblasts co-cultured of lung cancer cells. A series of co-culture experiments that employed cell counting kit-8 (CCK8), transwells, real-time polymerase chain reaction (RT-PCR) and Western blotting with HFL-1 fibroblasts and A549 human lung carcinoma cells were performed to learn more about tumor cell proliferation, migration and invasion; and to determine any change of epithelial mesenchymal transition (EMT)-associated tumor markers vimentin, matrix metallopro-teinase 2 (MMP2) and chemotaxis cytokines receptor 4 (CXCR4) mRNA levels. RESULTS: A549 cell proliferation in the presence of HFL-1 cells was not significantly increased compared with A549 cells alone, but A549 cell spheroid body formation was increased after co-culture, and treatment with gefitinib increased further. Our study also revealed that fibroblasts attenuated the lung cancer cell inhibition ratio of migration and invasion after gefitinib treatment in vitro. To further study this mechanism, RT-PCR analysis showed that vimentin, MMP2 and CXCR4 mRNA levels were more highly expressed in the lung cancer cells after co-culture, but did not obviously decrease compared with the control cells following gefitinib treatment. This suggests the mechanism by which fibroblasts attenuate gefitinib-induced expression of EMT-associated tumor markers. Finally, our results demonstrated that co-culture with A549 lung cancer cells does not alter the cell cycle distribution of HFL-1 fibroblasts. Furthermore, HFL-1 fibroblasts had no effect on the cell cycle distribution of HFL-1 cells treated with gefitinib. CONCLUSION: Gefitinib has lower anti-tumor activity on A549 lung cancer cells when co-cultured with HFL-1 fibroblasts.