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The mortality of heart failure after acute myocardial infarction (AMI) remains high. The aim of the present study was to analyze hub genes and immune infiltration in patients with AMI and heart failure (HF). The study utilized five publicly available gene expression datasets from peripheral blood in patients with AMI who either developed or did not develop HF. The unbiased patterns of 24 immune cell were estimated by xCell algorithm. Single-cell RNA sequencing data were used to examine the immune cell infiltration in heart failure patients. Hub genes were validated by quantitative reverse transcription-PCR (RT-qPCR). In comparison with the coronary heart disease (CHD) group, immune infiltration analysis of AMI patients showed that macrophages M1, macrophages, monocytes, natural killer (NK) cells, and NKT cells were the five most highly activated cell types. Five common immune-related genes (S100A12, AQP9, CSF3R, S100A9, and CD14) were identified as hub genes associated with AMI. Using RT-qPCR, we confirmed FOS, DUSP1, CXCL8, and NFKBIA as the potential biomarkers to identify AMI patients at risk of HF. The study identified several transcripts that differentiate between AMI and CHD, and between HF and non-HF patients. These findings could improve our understanding of the immune response in AMI and HF, and allow for early identification of AMI patients at risk of HF. [ABSTRACT FROM AUTHOR]

Nitrogen (N) is an important contributor in regulating plant growth and development as well as secondary metabolites synthesis, so as to promote the formation of tea quality and flavor. Theanine, polyphenols, and caffeine are important secondary metabolites in tea plant. In this study, the responses of Camellia sinensis roots to N deprivation and resupply were investigated by metabolome and RNA-seq analysis. N deficiency induced content increase for most amino acids (AAs) and reduction for the remaining AAs, polyphenols, and caffeine. After N recovery, the decreased AAs and polyphenols showed a varying degree of recovery in content, but caffeine did not. Meanwhile, theanine increased in content, but its related synthetic genes were down-regulated, probably due to coordination of the whole N starvation regulatory network. Flavonoids-related pathways were relatively active following N stress according to KEGG enrichment analysis. Gene co-expression analysis revealed TCS2, AMT1;1, TAT2, TS, and GOGAT as key genes, and TFs like MYB, bHLH, and NAC were also actively involved in N stress responses in C. sinensis roots. These findings facilitate the understanding of the molecular mechanism of N regulation in tea roots and provide genetic reference for improving N use efficiency in tea plant. [ABSTRACT FROM AUTHOR]

This study aimed to clarify the bioavailability mechanism of theaflavins by using the Caco-2 monolayer in vitro model. Prior to the transport of theaflavin (TF), theaflavin-3-gallate (TF3G), theaflavin-3'-gallate (TF3'G), and theaflavin-3, 3'-digallate (TFDG), we found the cytotoxicity of theaflavins was in the order of TF3'G>TFDG>TF3G>TF, suggesting the galloyl moiety enhances the cytotoxicity of theaflavins. Meantime, the galloyl moiety made theaflavins unstable, with the stability in the order of TF>TFDG>TF3G/TF3'G. Four theaflavins showed poor bioavailability with the Papp values ranging from 0.44X10-7 to 3.64X10-7 cm/s in the absorptive transport. All the theaflavins showed an efflux ratio of over 1.24. And it is further confirmed that P-glycoprotein (P-gp), multidrug resistance associated proteins (MRPs) and breast cancer resistance protein (BCRP) were all shown to contribute to the efflux transport of four theaflavins, with P-gp playing the most important role, followed by MRPs and BCRP. Moreover, theaflavins increased the expression of P-gp, MRP1, MPR3, and BCRP while decreased the expression of MRP2 at the transcription and translation levels. Additionally, the gallated theaflavins were degraded into simple theaflavins and gallic acids when transported through Caco-2 monolayers. Overall, the structural instability, efflux transporters, and cell metabolism were all responsible for the low bioavailability of four theaflavins in Caco-2 monolayers. [ABSTRACT FROM AUTHOR]

This paper aimed to clarify the absorption and transport of fluorine from different fermented teas in a Caco-2 cell model. Chemical composition analysis showed that tea polyphenols and catechins were the highest in green tea water extract (GE) and the lowest in dark tea water extract (DE), while the fluorine content was the lowest in GE and the highest in DE. The water extracts of green tea, black tea (BE), and dark tea were shown to vary significantly in their effects on the proliferation of Caco-2 cells, with IC50 values of 624.6 µg/mL, 710.5 µg/mL, and 1258.8 µg/mL for them, respectively, which were significantly higher than that of sodium fluoride (NaF, IC50 67.2 µg/mL) and suggest that DE has the lowest inhibitory activity and least toxicity to Caco-2 cells. Meanwhile, DE was significantly lower than GE or NaF and exhibited no difference from BE in the fluorine positive transport amount and apparent permeability coefficient (Papp) in the Caco-2 cell model, indicating the least fluorine bioavailability for DE. The fluorine Pratio (Papp(BL-AP)/Papp(AP-BL)) for the three tea extracts showed an upward trend with increasing treatment time and concentration and approached 1.5, indicating mainly passive diffusion as the fluorine transport form at low concentration and active transport at high concentration. The three tea extracts also varied significantly in fluorine bioavailability, with a lower fluorine toxicity and bioavailability for postfermented dark tea than green tea or black tea. The morphology of fluorine and the synergetic effect of polyphenol-oxidized polymers may be important influencing factors for fluorine bioavailability. This study has shed light on the absorption and transport of fluorine from different teas and facilitates the understanding of the related transport mechanism. [ABSTRACT FROM AUTHOR]

The tea plant is a hyper-accumulator of fluorine, especially in its mature leaves, which may negatively affect human health. In this study, the forms of fluorine in tea leaves and its bioaccessibility were analyzed. The results showed that tea polysaccharides accumulated about 68% fluorine of tea leaf. The bioaccessibility of fluorine in polysaccharides and tea water extract were lower than that of fluorine in sodium fluoride. The addition to polysaccharides by thearubigins and theabrownins, at a ratio of 1:2, reduced fluorine bioaccessibility. The addition of milk, more than 40 mL to 1 g polysaccharides, could also significantly reduce fluorine bioaccessibility, which may be attributed mainly to proteins and calcium compounds in milk. The present study suggests that the bioaccessibility of fluorine in tea is affected by the fluorine form and adding milk when drinking tea, which can effectively reduce side effects of fluorine in tea. [ABSTRACT FROM AUTHOR]

Tea tree (Camellia sinensis L.) is an hyper-accumulator of fluorine (F), especially in leaves. Here, the accumulation of different fluorine forms and their subcellular distribution in leaves and cell walls were analyzed in three tea cultivars (Fsensitive Wuniuzao, F-resistant Fudingdabai, and Fuyun No.6). Results indicated that the F content varied significantly in the three cultivars and increased with the maturity of leaves, with most F accumulated in cell walls. Specifically, the greatest amount of F was found in the water-soluble form, about 61.90-87.52% of the total fluorine, followed by the residual-fluorine, about 5.41-27.25%, the organic matter-bound fluorine, about 1.92-8.32%, and, with the lowest proportion, the iron-manganese-bound and exchangeable fluorine. Fluorine in the cell walls was mainly present in the water-soluble form, followed by residual-fluorine. There was a distinct difference between the three different cultivars in F concentration, subcellular distribution, and chemical forms. When compared with the two F-resistant cultivars, the F-sensitive Wuniuzao had higher water soluble F and less residual F in leaves and cell walls. These results suggest that mature leaves are the main F enrichment site, and the retention of F in the cell wall in a bound form might be an important way for tea plants to reduce F toxicity. [ABSTRACT FROM AUTHOR]

Background: Natural products have being used as potential inhibitors against carbohydrate-hydrolyzing enzymes to treat diabetes mellitus. Chinese dark tea has various interesting bioactivities. In this study, the active compounds from Qingzhuan dark tea were separated and their anti-diabetic activity was examined using an in vitro enzymatic model. Methods: The chloroform, ethyl acetate, n-butanol, sediment and residual aqua fractions of a Chinese dark tea (Qingzhuan tea) were prepared by successively isolating the water extract with different solvents and their in vitro inhibitory activities against α-glucosidase were assessed. The fraction with the highest inhibitory activity was further characterized to obtain the main active components of Qingzhuan tea. Results: The ethyl acetate fraction had the greatest inhibitory effect on α-glucosidase, followed by n-butanol, sediment and residual aqua fractions (with the IC50 values of 0.26 mg/mL, 2.94 mg/mL, 3.02 mg/mL, and 5. 24 mg/mL, respectively), mainly due to the high content of polyphenols. Among the eight subfractions (QEF1-8) isolated from the ethyl acetate fraction, QEF8 fraction showed the highest α-glucosidase inhibitory potential in a competitive inhibitory manner (the Ki value of 77.10 µg/mL). HPLC-MS analysis revealed that (-)-epigallocatechin gallate (EGCG) and (-)-epicatechin gallate (ECG) were the predominant active components in QEF8. Conclusion: These results indicated that Qingzhuan tea extracts exerted potent inhibitory effects against α-glucosidase, EGCG and ECG were likely responsible for the inhibitory activity in Qingzhuan tea. Qingzhuan tea may be recommended as an oral antidiabetic diet. [ABSTRACT FROM AUTHOR]