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1.
Sci Total Environ ; 947: 174540, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38977089

RESUMO

OBJECTIVE: The cardiovascular system effects of environmental low-dose radiation exposure on radiation practitioners remain uncertain and require further investigation. The aim of this study was to initially investigate and explore the mechanisms by which low-dose radiation may contribute to atherosclerosis through a multi-omics joint comprehensive basic experiment. METHODS: We used WGCNA and differential analyses to identify shared genes and potential pathways between radiation injury and atherosclerosis sequencing datasets, as well as tissue transcriptome immune infiltration level extrapolation and single-cell transcriptome data correction using the CIBERSORT deconvolution algorithm. Animal models were constructed by combining a high-fat diet with 5 Gy γ-ray whole-body low-dose ionizing radiation. The detection of NETs release was validated by enzyme-linked immunosorbent assay. RESULTS: Analysis reveals shared genes in both datasets of post-irradiation and atherosclerosis, suggesting that immune system neutrophils may be a key node connecting radiation to atherosclerosis. NETs released by neutrophil death can influence the development of atherosclerosis. Animal experiments showed that the number of neutrophils decreased (P < 0.05) and the concentration of NETs reduced after low-dose radiation compared with the control group, and the concentration of NETs significantly increased (P < 0.05) in the HF group. Endothelial plaques were significantly increased in the high-fat feed group and significantly decreased in the low-dose radiation group compared with the control group. CONCLUSIONS: Long-term low-dose ionizing radiation exposure stimulates neutrophils and inhibits their production of NETs, resulting in inhibition of atherosclerosis.


Assuntos
Aterosclerose , Aterosclerose/prevenção & controle , Animais , Camundongos , Armadilhas Extracelulares , Exposição à Radiação , Neutrófilos
2.
J Agric Food Chem ; 71(44): 16604-16617, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37876151

RESUMO

The potential biological function of tea and its active components on colitis has attracted wide attention. In this study, different tea active ingredients including tea polyphenols (TPPs), tea polysaccharides (TPSs), theabrownin (TB), and theanine (TA) have been compared in the intervention of dextran sulfate sodium (DSS)-induced colitis in mice. Specifically, TPP showed the greatest effect on colitis since it reduced 60.87% of disease activity index (DAI) compared to that of the DSS-induced colitis group, followed by the reduction of 39.13% of TPS and 28.26% of TB on DAI, whereas there was no obvious alleviative effect of TA on colitis. TPP, TPS, and TB could regulate the composition and abundance of gut microbiota to increase the content of short-chain fatty acids (SCFAs) and enhance intestinal barrier function. Further evidence was observed that TPP and TPS regulated the activation of Nrf2/ARE and the TLR4/MyD88/NF-κB P65 pathway to alleviate the colitis. Results of cell experiments demonstrated that TPP showed the greatest antiapoptosis and mitochondrial function protective capability among the tea ingredients via inhibiting the Cytc/Cleaved-caspase-3 signaling pathway. In summary, the superior anticolitis activity of TPP compared to TPS and TB is primarily attributed to its unique upregulation of the abundance of Akkermansia and its ability to regulate the mitochondrial function.


Assuntos
Colite , Microbioma Gastrointestinal , Animais , Camundongos , Proteínas Adaptadoras de Transdução de Sinal , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/genética , Defecação , Chá
3.
Anal Methods ; 15(43): 5823-5836, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37870766

RESUMO

Heavy metal pollution has become a growing concern in industrial, agricultural, and manufacturing processes, posing a significant threat to human health. Among these heavy metals, arsenic (As) is highly toxic and shares similar chemical properties and environmental behavior with other heavy metals. As(III) is particularly toxic compared to other forms of arsenic. Therefore, it is essential to develop a real-time, rapid, and sensitive method for the determination of As(III). In this study, we employed a unique bifunctional chelator, 1-(4-isothiocyanobenzyl)-ethylenediamine N,N,N',N'-tetraacetic acid (ITCBE), to prepare a complete antigen. Through a series of tests including balb/c mouse immunization, cell fusion (mouse L2041 spleen cells with mouse myeloma cells SP2/0), and subcloning, we generated four monoclonal cell lines (1C1, 2C2, 3A9, and 4A11). These cell lines demonstrated high purity, high affinity, and IC50 values of less than 50 µg mL-1. Monoclonal antibody 4A11, which exhibited a strong Raman signal, was selected as the probe, and Au@Ag 200 was utilized as the surface-enhanced Raman scattering (SERS) substrate for the preliminary establishment of SERS immunochromatographic test strips. The sensitivity of the SERS immunochromatographic test strips, measured through Raman signal detection, showed a significant improvement compared to the SERS immunochromatographic test strips analyzed by colorimetry (LOD = 49.43 µg mL-1 and LDR = 5.32-81.31 µg mL-1). The SERS immunochromatographic test strips achieved a LOD of 7.62 µg mL-1 and an LDR of 12.66-71.84 µg mL-1. This study presents innovative methodologies for the rapid detection of As(III) using SERS immunochromatographic test strips.


Assuntos
Arsênio , Nanotubos , Animais , Camundongos , Anticorpos Monoclonais , Ouro/química , Imunoensaio/métodos , Prata/química
4.
ACS Appl Mater Interfaces ; 15(37): 44109-44118, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37676637

RESUMO

Organophosphorus pesticides (OPPs) are extensively used in agricultural production, and the contamination caused by their residues has raised significant concerns regarding potential threats to human health. Herein, a novel fluorescence nanoprobe based on an enzyme-mediated silver nanoparticle-modified metal organic framework (AgNPs@PCN-224) was successfully prepared for the rapid detection of OPPs. Initially, AgNPs@PCN-224 were synthesized by reducing silver nitrate (AgNO3) using sodium borohydride (NaBH4) embedded into luminescent PCN-224. This triggered the inner filter effect, leading to fluorescence quenching. Meanwhile, under the catalysis of acetylcholinesterase (AChE) and choline oxidase (CHO), acetylcholine (ATCh) was decomposed to hydrogen peroxide (H2O2), which could destroy AgNPs to form Ag+ released from PCN-224 for fluorescence recovery. Instead, fenitrothion, an OPP, inhibited AChE activity, allowing the quenched fluorescence to be reactivated. Under the current optimum conditions, the fluorescence intensity had a good correlation (Y = -728.5370X + 2178.4248, R2 = 0.9869) over a dynamic range of fenitrothion concentrations from 0.1 to 500 ng/mL, with an LOD of 0.037 ng/mL. In addition, the anti-interference ability and robustness of the proposed sensor was verified for the monitoring of fenitrothion in tea with recoveries of 87.67-103.72% and the relative standard deviations (RSD) < 5.43%, indicating that the system has excellent prospects for OPP determination in practical applications. Furthermore, this work provides a universal platform for screening other enzyme inhibitors to detect OPPs.


Assuntos
Nanopartículas Metálicas , Praguicidas , Humanos , Fluorescência , Acetilcolinesterase , Fenitrotion , Peróxido de Hidrogênio , Compostos Organofosforados , Prata
5.
Foods ; 12(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36900607

RESUMO

Fenvalerate has the advantages of a broad insecticidal spectrum, high efficiency, low toxicity and low cost, and it is widely used in agriculture, especially in tea, resulting in the accumulation of fenvalerate residues in tea and the environment, posing a serious threat to human health. Therefore, the timely monitoring of fenvalerate residue dynamics is vital for ensuring the health of humans and the ecological environment, and it is necessary for establishing a fast, reliable, accurate and on-site method for detecting fenvalerate residues. Based on the methods of immunology, biochemistry and molecular biology, mammalian spleen cells, myeloma cells and mice were used as experimental materials to establish a rapid detection method of an enzyme-linked immunosorbent assay to detect the residues of fenvalerate in dark tea. Three cell lines-1B6, 2A11 and 5G2-that can stably secrete fenvalerate antibodies were obtained by McAb technology, and their sensitivities (IC50) were 36.6 ng/mL, 24.3 ng/mL and 21.7 ng/mL, respectively. The cross-reaction rates of the pyrethroid structural analogs were all below 0.6%. Six dark teas were used to detect the practical application of fenvalerate monoclonal antibodies. The sensitivity IC50 of the anti-fenvalerate McAb in PBS with 30% methanol is 29.12 ng/mL. Furthermore, a latex microsphere immunochromatographic test strip with an LOD of 10.0 ng/mL and an LDR of 18.9-357 ng/mL was preliminarily developed. A specific and sensitive monoclonal antibody for fenvalerate was successfully prepared and applied to detect fenvalerate in dark teas (Pu'er tea, Liupao tea, Fu Brick tea, Qingzhuan tea, Enshi dark tea and selenium-enriched Enshi dark tea). A latex microsphere immunochromatographic test strip was developed for the preparation of rapid detection test strips of fenvalerate.

6.
Cancers (Basel) ; 15(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36831670

RESUMO

Breast cancer is the most diagnosed cancer in women in the world. Mebendazole (MBZ) has been demonstrated to have preclinical efficacy across multiple cancers, including glioblastoma multiforme, medulloblastoma, colon, breast, pancreatic, and thyroid cancers. MBZ was also well tolerated in a recent phase I clinical trial of adults diagnosed with glioma. The mechanisms of action reported so far for MBZ include tubulin disruption, inhibiting angiogenesis, promoting apoptosis, and maintaining stemness. To elucidate additional mechanisms of action for mebendazole (MBZ), we performed RNA sequencing of three different breast cancer cell lines treated with either MBZ or vehicle control. We compared the top genes downregulated upon MBZ treatment with expression profiles of cells treated with over 15,000 perturbagens using the clue.io online analysis tool. In addition to tubulin inhibitors, the gene expression profile that correlated most with MBZ treatment matched the profile of cells treated with known hypoxia-inducible factor (HIF-1α and -2α) inhibitors. The HIF pathway is the main driver of the cellular response to hypoxia, which occurs in solid tumors. Preclinical data support using HIF inhibitors in combination with standard of care to treat solid tumors. Therefore, we tested the hypothesis that MBZ could inhibit the hypoxia response. Using RNA sequencing and HIF-reporter assays, we demonstrate that MBZ inhibits the transcriptional activity of HIFs in breast cancer cell lines and in mouse models of breast cancer by preventing the induction of HIF-1α, HIF-2α, and HIF-1ß protein under hypoxia. Taken together, our results suggest that MBZ treatment has additional therapeutic efficacy in the setting of hypoxia and warrants further consideration as a cancer therapy.

7.
Crit Rev Food Sci Nutr ; 63(25): 7598-7626, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35266837

RESUMO

Sleep disorders have received widespread attention nowadays, which have been promoted by the accelerated pace of life, unhealthy diets and lack of exercise in modern society. The chemical medications to improve sleep has shown serious side effects and risks with high costs. Therefore, it is urgent to develop efficient nutraceuticals from natural sources to ensure sleep quality as a sustainable strategy. As the second most consumed beverage worldwide, the health-promoting effects of tea have long been widely recognized. However, the modulatory effect of teas on sleep disorders has received much less attention. Tea contains various natural sleep-modulating active ingredients such as L-theanine (LTA), caffeine, tea polyphenols (TPP), tea pigments, tea polysaccharides (TPS) and γ-aminobutyric acid (GABA). This review focuses on the potential influence and main regulating mechanisms of different tea active ingredients on sleep, including being absorbed by the small intestine and then cross the blood-brain barrier to act on neurons in the brain as neurotransmitters, manipulating the immune system and further affect sleep-wake cycle by regulating the levels of cytokines, and controlling the gut microbes to maintain the homeostasis of circadian rhythm. Current research progress and limitations are summarized and several future development directions are also proposed. This review hopes to provide new insights into the future elucidation of the sleep-regulating mechanisms of different teas and their natural active ingredients and the development of tea-based functional foods for alleviating sleep disorders. HighlightsNatural sleep-modulating active ingredients in tea have been summarized.Influences of drinking tea or tea active ingredients on sleep are reviewed.Three main regulating mechanisms of tea active ingredients on sleep are explained.The associations among nervous system, immune system and intestinal microbiota are investigated.The potential of developing delivery carriers for tea active ingredients is proposed.


Assuntos
Microbioma Gastrointestinal , Transtornos do Sono-Vigília , Humanos , Chá , Sono , Polifenóis/farmacologia , Sistema Imunitário
8.
Front Endocrinol (Lausanne) ; 13: 1074516, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36465626

RESUMO

Background: Acupuncture is a widely practiced, convenient, and safe treatment modality within complementary and integrative medicine. Increasing studies have revealed the efficacy of acupuncture for the treatment of osteoporosis in both human and non-human subjects. The aim of the present study was to assess the improvement of osteoporosis after overall adjustment acupuncture (OA) as well as its endocrine-modulating effect in an ovariectomized rat model. Methods: In total, 32 female Sprague-Dawley (SD) rats were randomly divided into the sham, model, ovariectomy+estrogen (OVX+E), and OVX+OA (OVX+A) groups with eight rats in each group. The postmenopausal osteoporosis (PMOP) rat model was induced by bilateral ovariectomy. At 12 weeks after surgery, rats in the OVX+E group received estradiol (0.2 mg/kg/i.g./qod) for 12 weeks, and rats in the OVX+A group were treated with acupuncture at Zusanli (ST36), Shenshu (BL23), and Dazhu (BL11) points (qod) for 12 weeks. At the end of the treatment, all rats were sacrificed, and the body weight, uterus index, bone mineral density (BMD), bone mineral content (BMC), bone trabeculae structural parameters, femoral biomechanical properties, femoral histomorphology, and several hormone levels were examined. Results: In OVX rats, OA abrogated the body weight gain and improved osteoporosis in terms of BMD, BMC, bone trabeculae structural parameters, bone strength, and bone tissue histomorphology. Moreover, OA modulated the serum levels of estradiol, corticotropin releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and corticosterone (CORT). Conclusions: OA improves osteoporosis and exerts an endocrine-modulating effect in ovariectomized rats.


Assuntos
Terapia por Acupuntura , Osteoporose , Feminino , Ratos , Animais , Humanos , Ratos Sprague-Dawley , Osteoporose/terapia , Estradiol , Estrogênios , Peso Corporal
9.
Front Nutr ; 9: 837168, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35369078

RESUMO

Selenium-enriched mung bean (Se-MB) is a combination of mung bean (MB) and selenium (Se), which have a variety of potential biological activities. However, little is known about the skincare activity of Se-MB. The chemical composition of Se-MB fermentation broth (Se-MBFB) was analyzed to investigate the whitening, moisturizing, and anti-aging activities of Se-MBFB. The tyrosinase inhibition, anti-melanogenic in melanocytes (B16F10 cells), and moisturizing effect in human dermal fibroblasts (HDFs) were analyzed. Besides, the free radical scavenging activity of Se-MBFB was assessed in vitro. To verify the in vivo effects and the potential of practical applications of Se-MBFB, a clinical trial was conducted on the participants: 31 Chinese women aged 25-60 years, with no pigmentation disorder, no illness, no history of hypersensitivity reaction, and no use of skincare product on the face. The participants used an Se-MBFB masque for 15-20 min after cleaning the face. The measurement points were Week 0, 2, and 4 (W0, W2, and W4) after using the masque, and target sites were cheek and canthus. The following parameters were recorded on the target sites at each visit: melanin index, skin color, cuticle moisture content, transepidermal water loss, and crow's feet. The results demonstrated that Se-MBFB was rich in polyphenols, peptides, and γ-aminobutyric acid (GABA), displayed significant free radical scavenging and tyrosinase inhibiting activities, decreased the synthesis of melanin, and upregulated the aquaporin-3 (AQP3) expression. The test of the Se-MBFB mask showed that after 4 weeks of using the Se-MBFB facemask, the faces of the participants became whiter with reduced wrinkles and increased moisture content. Se-MB possessed the excellent whitening, moisturizing, and antioxidant efficacy, which could lay a scientific foundation for utilization and development of skincare products of Se-MB and its related industrial cosmetics products.

10.
Biomater Biosyst ; 5: 100038, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36825110

RESUMO

Protease has been widely used in biological and industrial fields. Developing efficient artificial enzyme mimics remains a major technical challenge due to the high stability of peptide bonds. Nanoenzymes with high stability, high activity and low cost, provided new opportunities to break through natural enzyme inherent limitations. However, compared with many nanomaterials with inherent peroxidase activity, the intrinsic mimic proteases properties of magnetic nanomaterials were seldom explored, let alone the interaction between magnetic nanomaterials and cellular proteins. Herein, we reported for the first time that magnetic CuFe2O4 possesses inherent protease activity to hydrolyze bovine serum albumin (BSA) and casein under physiological conditions, and the CuFe2O4 is more resistant to high temperature than the natural trypsin. It also exhibited significantly higher catalytic efficiency than other copper nanomaterials and can be recycled for many times. Protease participated in pathophysiological processes and all stages of tumor progression. Interesting, CuFe2O4 exhibited anti-proliferative effect on A549, SKOV3, HT-29, BABL-3T3 and HUVEC cells, as well as it was particularly sensitive against SKOV3 cells. CuFe2O4 was about 30 times more effective than conventional chemotherapy drugs oxaliplatin and artesunate against SKOV3 cells. In addition, CuFe2O4 also mediated the expression of intracellular proteins, such as MMP-2, MMP-9, F-actin, and NF-kB, which may be associated with global protein hydrolysis by CuFe2O4, leading to inhibition of cell migration. The merits of the high magnetic properties, good protease-mimic and antitumor activities make CuFe2O4 nanoparticles very prospective candidates for many applications such as proteomics and biotechnology.

11.
Food Res Int ; 148: 110594, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34507739

RESUMO

Diabetes and its related metabolic disorders are worldwide public health issues. Many studies have shown that changes in the structure and composition of the intestinal flora are closely related to the host's physiological and pathological processes. In this study, we aim to explore the effect of Liubao tea (LBT) extract on hyperglycemic mice with metabolic disorders and intestinal flora dysbiosis and to further study its regulatory effect on insulin resistance and its potential regulatory mechanism. Our results show that LBT had a good hypoglycemic effect and could significantly alleviate the metabolic disorder evoked by hyperglycemia. The gut microbial sequencing showed that LBT treatment increased the diversity of intestinal flora, increased the abundance of beneficial bacteria, and reduced the abundance of harmful or conditional pathogenic bacteria, as well as significantly altered 39 of the top 50 OTUs with abundance. Besides, LBT could activate the PI3K-Akt-PPARs-GLUT2 cascade signaling pathway to improve metabolic disorders, thereby alleviating insulin resistance. These results suggest that LBT has excellent potential to become a natural functional food for the prevention of hyperglycemia and insulin resistance.


Assuntos
Microbioma Gastrointestinal , Resistência à Insulina , Doenças Metabólicas , Animais , Glicemia , Doenças Metabólicas/tratamento farmacológico , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Chá
12.
J Sci Food Agric ; 101(15): 6563-6577, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34018615

RESUMO

BACKGROUND: Dark tea, comprising one of the six major teas, has many biological activities, which originate from their active substrates, such as polyphenols, polysaccharides, and so on. The hypoglycemic effect is one of its most prominent activities, although less is known about their evaluation and potential role in the hypoglycemic mechanism. RESULTS: In the present study, we separately analyzed the phytochemical composition, glycosidase inhibition and free radical scavenging activities, and hypoglycemic activity in type 2 diabetes mellitus mice, as well as the alleviation of insulin resistance in HepG2 cells of four dark tea aqueous extracts. The results showed that the phytochemical composition of dark tea aqueous extracts was significantly different, and they all had good glycosidase inhibition and free radical scavenging activities, in vivo hypoglycemic activity and alleviation of insulin resistance, and could also activate the phosphatidylinositol 3-kinase-Akt-perixisome proliferation-activated receptor cascade signaling pathway to regulate glucose and lipid metabolism, change the key enzyme activities related to glucose metabolism and antioxidant activity, and reduce oxidative stress and inflammatory factor levels. Among them, Liubao brick tea (LBT) and Pu-erh tea (PET) possessed better glycosidase inhibitory activity, in vivo hypoglycemic activity and improved insulin resistance activity, whereas Qingzhuan brick tea and Fuzhuan brick tea had better free radical scavenging activity, which may be explained by their distinct phytochemical compositions, such as tea proteins, polysaccharides, polyphenols, catechins, and tea pigments and some elements. CONCLUSION: Dark tea is a highly attractive candidate for developing antidiabetic food, LBT and PET may be good natural sources of agricultural products with anti-diabetic effects. © 2021 Society of Chemical Industry.


Assuntos
Glicemia/metabolismo , Camellia sinensis/metabolismo , Diabetes Mellitus Tipo 2/dietoterapia , Hipoglicemiantes/metabolismo , Resistência à Insulina , Fígado/metabolismo , Compostos Fitoquímicos/metabolismo , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Camellia sinensis/química , China , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Células Hep G2 , Humanos , Hipoglicemiantes/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo , Receptores Ativados por Proliferador de Peroxissomo/genética , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Compostos Fitoquímicos/química , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Chá
13.
Foods ; 11(1)2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-35010203

RESUMO

Recently, concerns about heavy metal cadmium ion (Cd2+) residue in asparagus have been frequently reported, and there is an urgent need to develop an effective, sensitive, and rapid detection method for Cd2+. In this study, we innovatively combined molecular microbiology to carry out the comparative screening of Cd2+ chelators in a green, efficient, and specific way. The knock-out putative copper-transporter gene (pca1Δ) yeast strain with high sensitivity to Cd2+ was first used to screen the Cd2+ chelator, and the optimum chelator 1-(4-Isothiocyanatobenzyl)ethylenediamine-N,N,N,N'-tetraacetic acid (ITCBE) was obtained. Additionally, a rapid latex microsphere immunochromatographic assay (LMIA) was developed, based on the obtained monoclonal antibody (mAb) with high specificity and high affinity (affinity constant Ka = 1.83 × 1010 L/mol), to detect Cd2+ in asparagus. The 50% inhibitive concentration (IC50) of test strip was measured to be 0.2 ng/mL, and the limit of detection (IC10) for qualitative (LOD, for visual observation) and quantitative detection (LOQ, for data simulation) of the test strip was 2 ng/mL and 0.054 ng/mL, respectively. In all, the developed mAb-based LMIA shows a great potential for monitoring Cd2+ in asparagus, even in vegetable samples.

14.
Environ Pollut ; 267: 115410, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32866867

RESUMO

It has been reported that heavy metal contamination can affect litter decomposition and soil properties through its impact on microbial communities. However, it is still unclear whether the expected changes in earthworm activities in responses to heavy metal contamination could affect these properties. Therefore, we quantified earthworm (Eisenia fetida) responses in survival rate to lethal cadmium (Cd) concentrations (0, 50, 100, 150, 200, 250, and 300 mg L-1), and in burrowing ability, physiological characteristics, and feeding rate (on poplar leaf litter) to sub-lethal Cd concentrations (0, 15, 30, and 45 mg kg-1). Finally, sub-lethal influences of Cd on the decomposition rate of poplar leaf litter and on soil properties were investigated in the present of E. fetida. The 12-, 24-, 36-, and 48-h LC50 of Cd for E. fetida were 276.0, 208.6, 192.6, 179.8 mg L-1, respectively. With increasing Cd concentration, malondialdehyde was stimulated, superoxide dismutase first increased and then decreased, while feeding rate, total borrowing length, and maximum burrowing depth consistently decreased. Consequently, leaf-litter decomposition rate and soil nutrient concentrations generally decreased with increasing Cd concentration. Our results indicate that, by affecting earthworm activities, Cd inhibited leaf-litter decomposition and led to the degradation of soil fertility. This study highlights the importance of earthworms in mediating soil functions under heavy metal stress.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Cádmio/análise , Cádmio/toxicidade , Folhas de Planta/química , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
15.
J Agric Food Chem ; 68(17): 4955-4965, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32286813

RESUMO

Qingzhuan tea (QZT) is a unique type of dark tea exclusively produced in Hubei Province of China. In the current study, liquid chromatography-mass spectrometry (LC-MS) coupled with multivariate analysis was applied to characterize the chemical composition of QZT and investigate the effect of QZT processing on its metabolic profile and sensory quality. The contents of polyphenols and flavonoids decreased significantly while the polysaccharides content remained stable, while the theabrownin content inversely increased during QZT processing. LC-MS-based metabolomics analyses revealed that the tea sample after microbial fermentation (MFT) was dramatically different from the sample before microbial fermentation (UFT), while MFT was very similar to QZT. A total of 102 compounds were identified as critical metabolites responsible for metabolic changes caused by QZT processing, with the contents of catechins and flavonoids significantly decreased, and some novel phenolic acids and catechin derivatives were formed. The sensory quality of QZT was mainly formed during microbial fermentation, which greatly reduced the astringency and bitterness of raw tea leaves and produced its characteristic woody and stale aroma as well as mellow taste. These results suggested that microbial fermentation is the critical process in changing the metabolic profile of raw tea leaves and forming the sensory quality of QZT.


Assuntos
Camellia sinensis/química , Folhas de Planta/química , Paladar , Adulto , Camellia sinensis/metabolismo , China , Cromatografia Líquida de Alta Pressão , Feminino , Fermentação , Flavonoides/química , Flavonoides/metabolismo , Humanos , Hidroxibenzoatos/química , Hidroxibenzoatos/metabolismo , Masculino , Metabolômica , Folhas de Planta/metabolismo , Polifenóis/química , Polifenóis/metabolismo , Espectrometria de Massas em Tandem , Chá/química
16.
Foods ; 9(3)2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32121649

RESUMO

Tea is a popular beverage and shows very strong in vitro antioxidant activity. However, the relationship among in vitro and in vivo antioxidant activities in teas is seldom reported. In this study, in vivo antioxidant and hepatoprotective activities of 32 selected Chinese teas were evaluated on a mouse model with acute alcohol-induced liver injury. The results showed that most teas significantly reduced the levels of alanine transaminase, aspartate transaminase, alkaline phosphatase, triacylglycerol, and total bilirubin in the sera of mice at a dose of 400 mg/kg. In addition, most teas greatly decreased the malondialdehyde level and increased the levels of superoxide dismutase, glutathione peroxidase, and glutathione in the liver of mice, indicating the antioxidant and hepatoprotective activities of teas. Furthermore, the in vivo antioxidant activity of dark tea was stronger than that of green tea, opposite to the results of the in vitro study. Among these 32 teas, Black Fu Brick Tea, Pu-erh Tea, and Qing Brick Tea showed the strongest antioxidant and hepatoprotective activities. Moreover, total phenolic content as well as the contents of epicatechin, gallocatechin gallate, and chlorogenic acid were found to contribute, at least partially, to the antioxidant and hepatoprotective actions of these teas. Overall, teas are good dietary components with antioxidant and hepatoprotective actions.

17.
Antioxidants (Basel) ; 8(6)2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31185622

RESUMO

Diabetes mellitus has become a serious and growing public health concern. It has high morbidity and mortality because of its complications, such as diabetic nephropathy, diabetic cardiovascular complication, diabetic neuropathy, diabetic retinopathy, and diabetic hepatopathy. Epidemiological studies revealed that the consumption of tea was inversely associated with the risk of diabetes mellitus and its complications. Experimental studies demonstrated that tea had protective effects against diabetes mellitus and its complications via several possible mechanisms, including enhancing insulin action, ameliorating insulin resistance, activating insulin signaling pathway, protecting islet ß-cells, scavenging free radicals, and decreasing inflammation. Moreover, clinical trials also confirmed that tea intervention is effective in patients with diabetes mellitus and its complications. Therefore, in order to highlight the importance of tea in the prevention and management of diabetes mellitus and its complications, this article summarizes and discusses the effects of tea against diabetes mellitus and its complications based on the findings from epidemiological, experimental, and clinical studies, with the special attention paid to the mechanisms of action.

18.
Int J Biol Macromol ; 120(Pt A): 853-858, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30171952

RESUMO

Selenium (Se)-containing polysaccharide, a Se-conjugate macromolecule, generally exhibited higher antitumor activity than its regular polysaccharide. Previously, we extracted Se-containing tea polysaccharides (Se-TPS) from Se-enriched tea, and explored its structure and antioxidant activity. In this study, we investigated antitumor activity of Se-TPS on sarcoma 180 (S-180), and compared with its regular polysaccharides TPS and dietary supplement Se-yeast. In vitro antitumor activity of Se-TPS was evaluated by MTT and LDH assays, and the results indicated that Se-TPS can significantly inhibit the proliferation of S-180 in dose-dependent manner (R2=0.97, p<0.0001). In S-180 cancer xenograft model in Kunming mice, Se-TPS oral administration at three doses of 50, 100 and 200mg/kg body weight daily for 13days resulted in significant tumor regression. At the same dose, Se-TPS exhibited significantly higher antitumor activity than TPS and Se-yeast. Importantly, Se-TPS can significantly increase the spleen and thymus indices of tumor-bearing mice, suggesting the safety and immunomodulatory activity of Se-TPS. Therefore, Se-TPS may be a desirable antitumor agent for therapeutic and immunomodulatory applications.


Assuntos
Polissacarídeos/administração & dosagem , Sarcoma 180/tratamento farmacológico , Selênio/química , Chá/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Imunomodulação/efeitos dos fármacos , Camundongos , Polissacarídeos/química , Sarcoma 180/patologia , Selênio/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Int J Biol Macromol ; 120(Pt A): 82-92, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30114426

RESUMO

Se-containing polysaccharide is known to Se-conjugated macromolecule, with potent bioactivities due to the synergistic effects of Se and native polysaccharide. It is not only explored as a novel Se source in dietary supplement, but also as the superb bioactive component owning various functions, including antioxidant, antitumor, immune-enhancement, hepatoprotective, antidiabetic, anti-inflammatory and neuroprotective activities. Se-containing polysaccharide can exert the efficacy of Se and polysaccharide, and its activities are much higher than those of Se or polysaccharide. In the last decades, numerous reports on Se-containing polysaccharide (including natural Se-containing polysaccharide and selenylated polysaccharide) appeared in literature. For the first time, this article systematically introduces recent advances on preparation, structural characterization and bioactivities of Se-containing polysaccharide in details, and discusses its future prospects and the weaknesses in the current study.


Assuntos
Adjuvantes Imunológicos , Antineoplásicos , Antioxidantes , Fármacos Neuroprotetores , Polissacarídeos , Selênio , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/isolamento & purificação , Adjuvantes Imunológicos/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Humanos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/farmacologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Selênio/química , Selênio/isolamento & purificação , Selênio/farmacologia
20.
ACS Appl Mater Interfaces ; 8(38): 25612-20, 2016 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-27588341

RESUMO

It is challenging to explore a unified solution for the treatment of oily wastewater from complex sources. Thus, membrane materials with flexible separation schemes are highly desired. Herein, we fabricated a smart membrane by electrospinning TiO2 doped polyvinylidene fluoride (PVDF) nanofibers. The as-formed beads-on-string structure and hierarchical roughness of the nanofibers contribute to its superwetting/resisting property to liquids, which is desirable in oil/water separation. Switched simply by UV (or sunlight) irradiation and heating treatment, the smart membrane can realize reversible separation of oil/water mixtures by selectively allowing water or oil to pass through alone. Most importantly, the as-prepared nanofiber membrane possesses outstanding antifouling and self-cleaning performance resulting from the photocatalytic property of TiO2, which has practical significance in saving solvents and recycling materials. This work provides a route for fabricating cost-effective, easily scaled up, and recyclable membranes for on-demand oil/water separation in versatile situations, which can be of great usage in the new green separation technology.

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