Electrochemical γ-Selective Deuteration of Pyridines.

Herein, we first report a γ-selective deuteration reaction of pyridines via H/D exchange without the need for preinstalled directing groups and transformable functional groups. The electrochemical process offers an attractive approach to producing γ-deuterated pyridines under gentle conditions. The broad substrate scope, excellent deuterium incorporation, and remarkable selectivity of the electrochemical method make it applicable for the late-stage modification of pharmaceutical molecules.

The dual role of 20(S)-protopanaxadiol in alleviating pulmonary fibrosis through the gut-lung axis.

BACKGROUND: Pulmonary Fibrosis (PF) is a progressive lung disease characterized by the diffuse interstitial tissue, leading to severe breathing difficulties. The existing treatment methods are primarily aimed at slowing the progression of the disease, underscoring the urgent need to discover new drug interventions targeting novel sites. The "gut-lung axis" represents a complex bidirectional communication system where the gut microbiota not only influences lung immunity but also responds to lung-derived signals. Recent advances have uncovered that alterations in gut microbiota composition can significantly impact respiratory diseases, offering new insights into their pathogenesis and potential therapeutic approaches. METHODS: This study is based on the fundamental concepts of the lung-gut axis and our previous research, further exploring the potential mechanisms of 20(S)-Protopanaxadiol (PPD) in ginseng against PF. We utilized a bleomycin-induced mouse model of PF and employed metabolomics and 16S rRNA sequencing to investigate the pathways through which PPD regulates the pulmonary fibrosis process via the gut-lung axis. Finally, we employed strategies such as antibiotic-induced microbiota disruption and fecal microbiota transplantation (FMT) to provide a comprehensive perspective on how PPD regulates pulmonary fibrosis through gut microbiota. RESULTS: The results of the bleomycin (BLM) mouse model of PF proved that PPD can directly act on the glycolysis- related metabolic reprogramming process in lung and the AMPK/STING pathway to improve PF. Combined the analysis of gut microbiota and related metabolites, we found that PPD can regulate the process of PF through the gut-lung axis target points G6PD and SPHK1. FMT and antibiotic-induced microbiota disruption further confirmed intermediate effect of gut microbiota in PF process and the treatment of PPD. Our study suggests that PPD can alleviate the process of pulmonary fibrosis either by directly acting on the lungs or by regulating the gut microbiota. CONCLUSION: This study positions PPD as a vanguard in the therapeutic landscape for pulmonary fibrosis, offering a dual mechanism of action that encompasses both modulation of gut microbiota and direct intervention at molecular targets. These insights highlight the immense therapeutic potential of harnessing the gut-lung axis.

Structure and functional properties of taro starch modified by dry heat treatment.

Taro starch (TS) was modified by dry heat treatment (DHT) for different periods (1, 3, 5, and 7 h at 130 °C) and temperatures (90, 110, 130, and 150 °C for 5 h) to expand its applications in food and other industries. The structure and functional properties of DHT-modified TS were characterized. It was found that TS granules became agglomerated after DHT, and the particle size, amylose content, solubility, and retrogradation enthalpy change of TS increased with increasing dry heating time and temperature, whereas the relative crystallinity, molecular weight, swelling power, gelatinization temperature, and enthalpy change decreased. The absorbance ratio of 1047 cm-1/1022 cm-1 for DHT-modified TS (except at 7 h) was higher than that of native TS. DHT increased the contact angle of TS in a time- and temperature-dependent manner. At a moderate strength, DHT increased the pasting viscosity, relative setback value, and storage modulus but decreased the relative breakdown value. Moreover, DHT (except at 150 °C) caused a decrease in the rapid digestive starch content and estimated glycemic index of TS. These results suggested that DHT-modified TS could be used in foods with high viscosity requirements, gel foods, and low-glycemic index starch-based foods.

Structural characterization of different starch-fatty acid complexes and their effects on human intestinal microflora.

Resistant starch type 5 (RS5), a starch-lipid complex, exhibited potential health benefits in blood glucose and insulin control due to the low digestibility. The effects of the crystalline structure of starch and chain length of fatty acid on the structure, in vitro digestibility, and fermentation ability in RS5 were investigated by compounding (maize, rice, wheat, potato, cassava, lotus, and ginkgo) of different debranched starches with 12-18C fatty acid (lauric, myristic, palmitic, and stearic acids), respectively. The complex showed a V-type structure, formed by lotus and ginkgo debranched starches, and fatty acid exhibited a higher short-range order and crystallinity, and lower in vitro digestibility than others due to the neat interior structure of more linear glucan chains. Furthermore, a fatty acid with 12C (lauric acid)-debranched starches complexes had the highest complex index among all complexes, which might be attributed to the activation energy required for complex formation increased with the lengthening of the lipid carbon chain. Therefore, the lotus starch-lauric acid complex (LS12) exhibited remarkable ability in intestinal flora fermentation to produce short-chain fatty acid (SCFAs), reducing intestinal pH, and creating a favorable environment for beneficial bacteria.

Mechanism of synergistic stabilization of emulsions by amorphous taro starch and protein and emulsion stability.

Amorphous taro starch (TS)/whey protein isolate (WPI) mixtures were prepared using pasting treatment. The TS/WPI mixtures and their stabilized emulsions were characterized to determine the emulsion stability and the mechanism of synergistic stabilization of emulsions. As WPI content increased from 0% to 13%, the paste final viscosity and retrogradation ratio of the TS/WPI mixture gradually decreased from 3683 cP to 2532 cP and from 80.65% to 30.51%, respectively. As the WPI content increased from 0% to 10%, the emulsion droplet size decreased gradually from 96.81 µm to 10.32 µm, and the storage modulus G' and stabilities of freeze-thaw, centrifugal, and storage increased gradually. Confocal laser scanning microscopy revealed that WPI and TS were mainly distributed at the oil-water interface and droplet interstice, respectively. Thermal treatment, pH, and ionic strength had little influence on the appearance but had different influences on the droplet size and G', and the rates of droplet size and G' increase under storage varied with different environmental factors.

Erratum: MicroRNA-423 enhances the invasiveness of hepatocellular carcinoma via regulation of BRMS1.

[This corrects the article on p. 5576 in vol. 9, PMID: 29312509.].

Loadings of lycopene in emulsion and sodium alginate-K-carrageenan composite systems: Preparation, characterization, bioaccessibility, and kinetics.

This research aims to prepare capsules emulsion using gallic acid (GA), dextran (DEX), bovine serum albumin (BSA), sodium alginate, and K-carrageenan (K-Car) as the biological delivery system of lycopene. The stability and bioaccessibility of lycopene were further improved through encapsulation of covalent complex of sodium alginate and K-Car. The molecular weight distribution and secondary structure of the conjugates were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared spectroscopy (FTIR). The storage stability of the emulsion stabilized by conjugates was measured with Turbiscan stability index (TSI) and fluctuation of the particle size. The TSI value of ternary conjugates was 18.7 (37℃) with particle sizes ranging from 208 to 319 nm. Then, the changes of three-dimensional reticulate structures and physical properties of sodium alginate-K were analyzed by scanning electron microscopy (SEM) and TPA. The thermal stability of the sodium alginate-K-Car composite systems was increased compared with sodium alginate. The bioaccessibility of lycopene was significantly improved under the dual embedding of BSA-DEX-GA conjugate emulsion and sodium alginate-K-Car composite systems.

Stability and bioaccessibility improvement of capsorubin using bovine serum albumin-dextran-gallic acid and sodium alginate.

This study attempted to prepare ternary conjugate emulsion from bovine serum albumin (BSA), dextran (DEX) and gallic acid (GA) to improve the stability of conjugate emulsion and the bioaccessibility of capsorubin. The release of capsorubin was further delayed by sodium alginate capsules in the intestinal phase. First, protein formed new functional groups and covalent bonds was analyzed by Fourier transform infrared (FTIR) and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Next, the stability of the ternary conjugate showed distinct pH correlation and the higher stability near the isoelectric point. Finally, the bioaccessibility of capsorubin embedded in sodium alginate emulsion was higher than that of ternary conjugate emulsion (65% and 34%).

Effects of celery powder on wheat dough properties and textural, antioxidant and starch digestibility properties of bread.

In order to investigate the effects of celery powder (CP) on bread quality, wheat flour was replaced by CP which was produced from two celery varieties ('Jinnan Shiqin' and 'Ventura') at different levels (1, 2, 3 and 5/100 g flour). For both kinds of CPs, Mixolab analysis showed that the water absorption of dough increased with the increase of CP, while the protein network weakening (C2), peak viscosity (C3) and crystallinity of starch (C5-C4) decreased. The specific volume of bread decreased at higher CP level, whereas its crumb hardness and chewiness showed a reverse trend. The addition of CP significantly increased the total phenolics content of bread, and thus caused a significant improvement in antioxidant activities. The addition of CP significantly reduced the content of rapidly digestible starch in bread, while the contents of slowly digestible starch and resistant starch were increased. Additionally, bread prepared with a higher CP content showed a lower predicted glycaemic index. Based on the results of sensory analysis, bread incorporated with 2 g/100 g flour for 'Jinnan Shiqin' or 1 g/100 g flour for 'Ventura' didn't show significant effect on its overall acceptability. The present study indicated that addition of CP could be an effective way to produce a bread with higher antioxidant activity and lower starch digestibility.

Protective effect of apple phlorizin on hydrogen peroxide-induced cell damage in HepG2 cells.

Apple phlorizin has many biological activities, such as antioxidant and liver protection. The present study aimed to evaluate the roles of apple phlorizin against hydrogen peroxide (H2 O2 )-induced oxidative damage in HepG2 cells. In this study, treatment with apple phlorizin (100 and 150 µg/ml) decreased the production of reactive oxygen species and alleviated apoptosis as well as DNA damage in H2 O2 -induced HepG2 cells. These effects were associated with the increased activity of antioxidant enzymes, enhanced the ARE-driven phase II antioxidant gene expression and its upstream Nrf2 protein expression, and decreased apoptosis-related gene expression. However, the phase II antioxidant gene expression and Nrf2 protein expression upregulated by phlorizin were reversed by Nrf2 shRNA transfection. These results showed that phlorizin relieves oxidative stress, DNA damage, and apoptosis in H2 O2 -induced HepG2 cells, at least partially, by regulating the expression of Nrf2 protein and apoptosis-related genes. PRACTICAL APPLICATIONS: Apple phlorizin is a polyphenol compound extracted from apple or apple juice. This report highlighted a protective effect of phlorizin on antioxidant stress, DNA damage, and apoptosis in H2 O2 -induced HepG2 cells. These results suggested that phlorizin may be developed for functional foods.

The Zea mays mutants opaque2 and opaque16 disclose lysine change in waxy maize as revealed by RNA-Seq.

In maize, opaque2 (o2) and opaque16 (o16) alleles can increase lysine content, while the waxy (wx) gene can enhance the amylopectin content of grains. In our study, o2 and o16 alleles were backcrossed into waxy maize line (wxwx). The o2o2o16o16wxwx lines had amylopectin contents similar to those of waxy line. Their nutritional value was better than waxy line, but the mechanism by which the o2 and o16 alleles increased the lysine content of waxy maize remained unclear. The o2o2o16o16wxwx lines and their parents on kernels (18th day after pollination) were subjected to RNA sequencing (RNA-Seq). The RNA-Seq analysis revealed 272 differentially expressed genes (DEGs). Functional analyses revealed that these DEGs were mainly related to biomass metabolism. Among them, in o2o2o16o16wxwx lines, 15 genes encoding α-zein were down-regulated, which resulted in the reduction of α-zein synthesis and increased lysine content; lkr/sdh1 and Zm00001d020984.1 genes involved in the lysine degradation pathway were down-regulated, thereby inhibited lysine degradation; sh2, bt2 and ae1 genes involved in starch metabolism were upregulated, leaded to wrinkling kernel and farinaceous endosperm. Our transcriptional-level identification of key genes responsible for increased grain lysine content and farinaceous endosperm formation following introgression of o2 and o16 alleles should promote molecular breeding for maize quality.

Transcriptome Dynamics of Double Recessive Mutant, o2o2o16o16, Reveals the Transcriptional Mechanisms in the Increase of Its Lysine and Tryptophan Content in Maize.

In maize, pyramiding of o2 and o16 alleles can greatly improve the nutritional quality of grains. To dissect its molecular mechanism, we created a double recessive mutant line, o2o2o16o16, by introgression of the o2 and o16 alleles into the wild-type maize inbred line, by molecular marker-assisted backcross selection. The kernels (18 day after pollination (DAP), 28 DAP, and 38 DAP) of the o2o2o16o16 mutant and its parent lines were subject to RNA sequencing (RNA-Seq). The RNA-Seq analysis revealed that 59 differentially expressed genes (DEGs) were involved in lysine metabolism and 43 DEGs were involved in tryptophan metabolism. Among them, the genes encoding AK, ASADH, and Dap-F in the lysine synthesis pathway were upregulated at different stages of endosperm development, promoting the synthesis of lysine. Meanwhile, the genes encoding LKR/SDH and L-PO in the lysine degradation pathway were downregulated, inhibiting the degradation of lysine. Moreover, the genes encoding TAA and YUC in the tryptophan metabolic pathway were downregulated, restraining the degradation of tryptophan. Thus, pyramiding o2 and o16 alleles could increase the lysine and tryptophan content in maize. These above results would help to uncover the molecular mechanisms involved in the increase in lysine and the tryptophan content, through the introgression of o2 and o16 alleles into the wild-type maize.

Inhibition of NET-1 suppresses proliferation and promotes apoptosis of hepatocellular carcinoma cells by activating the PI3K/AKT signaling pathway.

The present study aimed to elucidate the underlying mechanism of neuroepithelial cell transforming 1 (NET-1), a member of the Ras homolog gene family, in hepatocellular carcinoma (HCC). To determine the association between the expression of NET-1 and the proliferation and migration of MHCC97-H cells, the cells were transfected with NET-1 small interfering (si)RNA and si negative control. Following transfection with NET-1 siRNA, the proliferation rate of MHCC97-H cells decreased significantly and the percentage of apoptotic cells increased. The HCC cell line MHCC97-H was used in the present study as it exhibited an increased expression level of NET-1 compared with the MHCC97-L cell line. Expression levels of apoptosis-associated proteins including apoptosis regulator Bax (Bax), cyclinD1, apoptosis regulator Bcl-2 (Bcl-2) and caspase-3 were determined. Expression levels of phosphoinositide 3-kinase (PI3K) and protein kinase B (AKT) and their phosphorylated forms were also measured by western blotting. Following NET-1 knockdown, the expression of Bax and cyclinD1 decreased, the expression of Bcl-2 and caspase-3 increased, and the PI3K/AKT signaling pathway was inhibited. The results of the present study suggest that inhibition of NET-1 can suppress the progression of HCC by targeting the PI3K/AKT signaling pathway. NET-1 expression level in HCC cells increased compared with normal liver cells.

Molecular Mechanisms Underlying Increase in Lysine Content of Waxy Maize through the Introgression of the opaque2 Allele.

The opaque2 (o2) mutation in maize is associated with high lysine content in endosperm and good nutritional value. To improve the nutritional quality of waxy maize, the o2 allele was introgressed into the wxwx line using marker-assisted backcrossing selection technology. The lysine content of o2o2wxwx lines was higher than that of the wxwx line. To reveal the mechanism of increasing lysine content through introgression of the o2 in waxy maize, the transcriptome on kernels (18th day after pollination) of the o2o2wxwx and parent lines was analyzed using RNA-sequencing (RNA-Seq). The RNA-Seq analysis revealed 49 differentially expressed genes (DEGs). Functional analysis showed that these DEGs were mostly related to the catalytic activity and metabolic processes. The O2 gene regulated multiple metabolic pathways related to biological processes (BP) and molecular function (MP) during waxy maize endosperm development. In particular, in the o2o2wxwx lines, the two genes that encode the EF-1α and LHT1 were up-regulated, but the gene that encodes sulfur-rich proteins was down-regulated, raising the grain lysine content. These findings are of great importance for understanding the molecular mechanism underlying the lysine content increase due to o2 allele introgression into waxy maize.

NET-1 promotes invasion, adhesion and growth of hepatocellular carcinoma by regulating the expression of BAX, caspase 3, caspase 8 and BCL2.

Dysregulation of neuroepithelial transforming gene-1 (NET-1) has been shown in hepatocellular carcinoma (HCC) patients. We aimed to evaluate the influence of NET-1 on HCC invasion, adhesion and growth. In vitro cellular functional assays including invasion and adhesion were performed to evaluate the effects of knockdown and overexpression of NET-1. HCC cells were transplanted into nude mice, and tumor growth was assessed. BAX, caspase 3, caspase 8 and BCL2 protein levels were detected by western blot. After transfection with NET-1 siRNA, NET-1 positive ratio in HCC cells significantly decreased. Cell invasion and adhesion assay showed that knockdown of NET-1 reduced the invasion and adhesion ability of HCC cells, whereas overexpression of NET-1 increased the ability. The evaluation of tumor growth revealed that NET-1 knockdown significantly decreased tumor volume and weight, while NET-1 overexpression promoted tumor growth in nude mice. Western blot showed that NET-1 knockdown increased BAX, caspase 3 and caspase 8 expression but decreased BCL2 expression, whereas NET-1 overexpression significantly down-regulated BAX, caspase 3 and caspase 8 expression but increased BCL2 expression. Our data suggest that NET-1 promotes HCC invasion, adhesion and growth by regulating BAX, caspase 3, caspase 8 and BCL2 expression.

An integrated analysis of genome-wide DNA methylation and gene expression data in hepatocellular carcinoma.

Despite progress in the treatment of hepatocellular carcinoma (HCC), 5-year survival rates remain low. Thus, a more comprehensive approach to explore the mechanism of HCC is needed to provide new leads for targeted therapy. We performed an integrated analysis to discover the relationship between DNA methylation and gene expression in hepatocellular carcinoma (HCC). DNA methylation and gene expression data for HCC were downloaded from The Cancer Genome Atlas (TCGA) database, and differential analysis was performed. Correlation analysis between DNA methylation and gene expression data was then performed in R language. Finally, we selected several crucial genes and evaluated their potential use as diagnostic biomarkers for HCC. In total, 1135 differentially DNA-methylated CpG sites (DMCs), 377 differentially methylated regions (DMRs), and 1194 differentially expressed genes (DEGs) were identified in HCC. Among the DEGs, 14 genes (ALX3, B4GALNT1,CTHRC1,DLX5,EMX1,IRX3,OTX1,SIX2,TLX1,VASH2,ZIC2,ZIC4,ZIC5, and ZNF695) exhibited changes in DNA methylation in terms of CpG sites or CpG island (CGI) level, of which TLX1 and ZIC4 had the most DMCs (12 and 13, respectively). Further analysis of CTHRC1,ZIC4,SIX2,VASH2,IL17D,TLX1,OTX1, and LART, examining alterations in both DNA methylation and gene expression level in HCC, showed their potential diagnostic value for HCC was better at the gene expression level than that the DNA methylation level. The DNA methylation status of CTHRC1,VASH2, and IL7D was significantly associated with HCC overall survival (P-value <0.05). This systemic analysis identified a group of novel gene signatures (CTHRC1,ZIC4, and OTX1) that may be regulated by DNA hypermethylation, which may be closely associated with HCC.

Purification, characterization and immunomodulatory activity of polysaccharides from stem lettuce.

Stem lettuce has a long history of cultivation in China and possesses high nutritional and medicinal value. In our previous studies, extraction optimization, characterization, and bioactivities of stem lettuce polysaccharides (SLP) were investigated. In this study, SLP were further separated into two purified polysaccharides, SLP-1 and SLP-2, by anion exchange chromatography followed by size exclusion chromatography. SLP-1, with a molecular weight of 90 KDa, was mainly composed of galacturonic acid, galactose and arabinose in a molar ratio of 17.6:41.7:33.9. SLP-2, with a molecular weight of 44 KDa, was mainly composed of mannose, galacturonic acid, galactose and arabinose in a molar ratio of 11.5:69.5:9.3:8.2. In addition, both purified polysaccharides contain sulphate radicals, have triple helical structures and can promote macrophage proliferation without cytotoxicity. SLP-2 was better able to stimulate phagocytic and nitric oxide production than SLP-1. The results suggest that polysaccharides from stem lettuce could be explored as immunomodulatory agents in the field of pharmaceuticals and functional foods.

Purification, characterization and immunomodulatory activity of water extractable polysaccharides from the swollen culms of Zizania latifolia.

The swollen culms of Zizania latifolia is a popular vegetable and traditional herbal medicine mainly consumed in some Asian countries. In our previous study, water extractable polysaccharide (ZLPs-W) and alkali extractable polysaccharide (ZLPs-A) was sequentially prepared from the swollen culms of Zizania latifolia. In vitro cell assay revealed that ZLPs-W without cytotoxicity had higher immunomodulatory activity than ZLPs-A. Therefore, in this study, ZLPs-W was further separated to three purified polysaccharides of ZLPs-W1, ZLPs-W2, and ZLPs-W3 by anion exchange chromatography and size exclusive chromatography in sequence. They were found to be homogeneous polysaccharides in ß-type glycosidic linkage. ZLPs-W1 and ZLPs-W2 without triple helix conformation mainly contained Glc in molar percentage of 96.47% and 85.1%, respectively. ZLPs-W3 with triple helix conformation mainly consisted of Man, Rha, GalA, Glc, Gal and Ara in the molar ratio of 10.23:14.14:37.44:17.14:16.54:4.51. In addition, all the three purified polysaccharides could effectively enhanced the proliferation, phagocytosis, and nitric oxide production of murine macrophage RAW 264.7, suggesting that they possessed a potent immunostimulatory activity and could be developed as immunomodulator in medicine or functional food areas.

Optimization of water-soluble polysaccharides from stem lettuce by response surface methodology and study on its characterization and bioactivities.

Stem lettuce is widely consumed as a vegetable in China. It is also used as a traditional Chinese medicine for a long time. Up to now, no information is available for stem lettuce polysaccharide (SLP). In this study, extraction optimization, characterization, and antioxidant activity of SLP was investigated.The maximum SLP yield of 20.89% was obtained under the optimal extraction conditions as follows: extraction temperature 95°C, extraction time 3.3h and ratio of water to material 25mL/g. The sulfate content of SLP was 5.82% and the main monosaccharides were GalA, Gal, and Ara with a mole ratio of 49.2: 23.3: 22.9. FT-IR spectrum and HPGPC result further indicated that SLP is a sulfated polydisperse heterpolysaccharide. Congo-red test and AFM scan indicated that SLP might be branching and intertwining structure with triple helix conformation. Moreover, SLP exhibited potent antioxidant activity and α-amylase inhibitory activity, hence it could be used as a potential natural antioxidant and hypoglycemic agent in medicine or functional food fields.

MicroRNA-423 enhances the invasiveness of hepatocellular carcinoma via regulation of BRMS1.

Tumor metastasis portrayed the most serious challenges of cancer as it is the major cause of mortality in patients with solid tumors, including hepatocellular carcinoma (HCC). In this regard, anti-metastatic genes have a great potential for metastasis inhibition. Recent evidence pointed to a role of Breast cancer metastasis suppressor 1 (BRMS1) in suppression of metastasis of several types of cancers, whereas the regulation of BRMS1 in HCC remains unknown. Here, we used bioinformatics analyses to predict BRMS1-targeting microRNAs (miRNAs), and evaluated the functional binding of miRNAs to BRMS1 mRNA using a dual luciferase reporter assay. Among all BRMS1-targeting miRNAs, we only detected significant expression of miR-626, miR-1289 and miR-423 in HCC specimens. Specifically, we found that only miR-423 significantly inhibited protein translation of BRMS1 via specific binding to 3'-UTR of the BRMS1 mRNA. Moreover, we detected significantly lower levels of BRMS1 and significantly higher levels of miR-423 in the HCC specimens, relative to paired adjacent non-tumor liver tissue. Furthermore, BRMS1 and miR-423 levels were correlated inversely. Overexpression of miR-423 significantly decreased BRMS1 levels and promoted HCC cell invasion, while depletion of miR-423 significantly increased BRMS1 levels and inhibited HCC cell invasion. This study sheds light on miR-423 as a crucial factor that enhances HCC cell invasiveness, and suggests miR-423 as a promising therapeutic target for HCC treatment.