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This study was aimed to investigate the potential ameliorative effects of omega-3 (ω3) fatty acids against acrylamide (ACR)-induced neurotoxicity. Thirty-two adult male Sprague Dawley rats were randomly assigned into four groups (n = 8) as follows: control, ω3 fatty acids (1000 mg/kg bwt/day orally), ACR-treated (50 mg/kg bwt/day IP) and ACR plus ω3 fatty acids group. Treatments were performed every other day for 21 consecutive days. ACR induced abnormal gait and elevated serum levels of proinflammatory cytokines (IL-6 and TNF-α), brain and spinal cord MDA levels and decreased brain and spinal cord GSH levels. Moreover, it reduced neurotransmitters (acetylcholine, GABA, serotonin and noradrenaline levels) and increased AChE activity in brain tissues. Histopathologically, ACR caused various degenerative changes, necrosis and glial cell activation in the cerebrum, cerebellum, hippocampus, spinal cord and sciatic nerve. Likewise, the histomorphometric analysis was constant with ACR-induced neurotoxicity. The ACR induced axonal atrophy and myelin disruption and decreased g-ratio of the sciatic nerve. Immunohistochemically, strong positive expressions of apoptotic marker caspase-3 and astroglial GFAP in the examined tissues were detected. Contrariwise, concurrent administration of ω3 fatty acids partially attenuated ACR impacts, as it improved the gait performance, reduced oxidative stress and pro-inflammatory cytokines, and modulate the levels of the neurotransmitters. It also ameliorated the intensity of ACR-induced histopathological and histomorphometric alterations within the examined nervous tissues. It could be concluded that ω3 fatty acids have antioxidant, anti-inflammatory and anti-apoptotic potentials against ACR neurotoxicity via suppression of oxidative stress, lipid peroxidation and pro-inflammatory cytokines, and inhibition of AChE activity and downregulation of caspase-3 and GFAP expressions in the nervous tissues. 相似文献
24.
The effects of heat treatment on the antigenicity and potential allergenicity of α-Lactalbumin (α-LA), β-Lactoglobulin (β-LG), α-casein (α-CN), and β-casein (β-CN) in milk protein concentrates (MPCs) were investigated at temperatures in the range of 65–100°C for times from 10 to 30?min. The antigenicity and potential allergenicity of α-LA decreased significantly. The antigenicity of β-LG was sharply increased throughout the heat treatment, while the potential allergenicity decreased significantly only at 85°C and 100°C for 25?min. The antigenicity of α-CN and β-CN showed fluctuated changes, but were all lower than untreated sample. The α-CN potential allergenicity decreased when heated at 65°C and 70°C for 25?min. Compared with untreated sample, the potential allergenicity of β-CN increased sharply after heat treatment. The results showed that different proteins in the MPCs showed different sensitivities under heat treatment. 相似文献
25.
《International immunopharmacology》2015,25(2):166-168
Components of the plasma proteome, particularly serum albumin, have been shown to compromise the accuracy of protein microarray technologies through non-specific binding interactions. Optimisation of array conditions is imperative to help address these problems. Here we demonstrate how modifications to array printing conditions and processing methodology can influence the reliability of data output. In particular, we demonstrate that whilst some glycerol is necessary to maintain specific binding signals, it also increases non-specific binding of albumin. Concentrations of 20% glycerol in the printing buffers are therefore recommended. The findings presented here provide opportunities for increased accuracy in plasma protein detection for possible future diagnostic applications. 相似文献
26.
3-monochoropropane-1, 2-diol (3-MCPD) esters from edible oils are considered to be a possible risk factor for adverse effects in human. In the present study, the exposure assessment of 3-MCPD esters to Chinese population was performed. A total of 143 edible oil and fat samples collected from Chinese markets were determined for the concentrations of 3-MCPD esters. The concentration data together with the data of fats consumed were analyzed by the point evaluation and probabilistic assessment for the exposure assessment. The point evaluation showed that the mean daily intake (DI) of 3-MCPD esters were lower than the value of provisional maximum tolerable daily intake (PMTDI) of 3-MCPD (2 µg/kg BW/d). The mean DI values in different age groups obtained from probabilistic assessment were similar to the results of the point evaluation. However, in high percentiles (95th, 97.5th, 99th), the DI values in all age groups were undesirably higher than the value of PMTDI. Overall, the children and adolescents exposed more to 3-MCPD esters than the adults. Uncertainty was also analyzed for the exposure assessment. Decreasing the level of 3-MCPD esters in edible oils and consuming less oil were top priority to minimize the risk of 3-MCPD esters. 相似文献
27.
Laurence P. Diggs Benjamin Ruf Chi Ma Bernd Heinrich Linda Cui Qianfei Zhang John C. McVey Simon Wabitsch Sophia Heinrich Umberto Rosato Walter Lai Varun Subramanyam Thomas Longerich Sven H. Loosen Tom Luedde Ulf Peter Neumann Sabina Desar David Kleiner Tim F. Greten 《Journal of hepatology》2021,74(5):1145-1154
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28.
Wenfeng Li Nianwu He Lingmin Tian Xiaolong Shi Xingbin Yang 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2016,24(3):527
A polyphenol-enriched extract from selenium-enriched Ziyang green tea (ZTP) was selected to evaluate its antitumor effects against human breast cancer MCF-7 cells. In ZTP, (−)-epigallocatechin gallate (28.2%) was identified as the major catechin, followed by (−)-epigallocatechin (5.7%) and (−)-epicatechin gallate (12.6%). ZTP was shown to inhibit MCF-7 cell proliferation (half maximal inhibitory concentration, IC50 = 172.2 μg/mL) by blocking cell-cycle progression at the G0/G1 phase and inducing apoptotic death. Western blotting assay indicated that ZTP induced cell-cycle arrest by upregulation of p53 and reduced the expression of CDK2 in MCF-7 cells. ZTP-caused cell apoptosis was associated with an increase in Bax/Bcl-2 ratio, and activation of caspase-3 and -9. MCF-7 cells treated with ZTP also showed an overproduction of reactive oxygen species, suggesting that reactive oxygen species played an important role in the induction of apoptosis in MCF-7 cells. This is the first report showing that ZTP is a potential novel dietary agent for cancer chemoprevention or chemotherapy. 相似文献
29.
Impacts of the Maillard reaction conditions (maltose/parvalbumin weight ratio, reaction temperature and reaction time) on the antigenicity of parvalbumin (PV) were explored using response surface methodology. The model to predict the antigenicity of PVand an optimal reaction condition were obtained. In addition, the antigenicity, immunoglobulin E (IgE) binding ability and amino acid composition of PV-maltose were analysed. The reaction temperature showed a significant effect on the antigenicity of PV. The optimal reaction condition was: maltose/PV weight ratio was 2.04, reaction temperature was 67.15°C and reaction time was 74.25 h. The predicted antigenicity was 0.276 µg mL?1 under these conditions, and the test antigenicity was 0.388 µg mL?1. The IgE binding ability of PV-maltose was significantly suppressed after Maillard reaction. Therefore, Maillard reaction was an effective way to control the main allergen of grass carp. 相似文献
30.
Jian-Xin Huang Jun Zhang Xiao-Rui Zhang Kun Zhang Xiao Zhang Xiao-Rui He 《Pharmaceutical biology》2014,52(10):1237-1243
Context: Podophyllotoxin, a pharmaceutically important bioactive compound of Podophyllum sps. (Berberidaceae), is in great demand worldwide as an anticancer and antivirus drug precursor. However, the source of podophyllotoxin is very limited due to the endangered status of the Podophyllum plant.Objective: The aim of this study was to isolate podophyllotoxin-producing endophytic fungi from Sinopodophyllum hexandrum (Royle) Ying (1979) (Berberidaceae) plants of the Taibai Mountains of China in order to obtain bioactive compounds.Materials and methods: The strains producing kaempferol and podophyllotoxin were screened by thin-layer chromatography (TLC) analysis. The presence of kaempferol and podophyllotoxin in extracts of these strains was further confirmed by high-performance liquid chromatography (HPLC) and nuclear magnetic resonance (NMR) analyses.Results: Among six endophytic fungi isolated from the rhizomes of S. hexandrum, one strain was able to produce kaempferol. Another strain, named TW5, was able to produce both kaempferol and podophyllotoxin simultaneously according to the TLC, HPLC, and NMR results. The podophyllotoxin yield of TW5 was calculated to be 49.3?μg/g of mycelial dry weight after 7-d fermentation. Strain TW5 was identified morphologically and phylogenetically to be Mucor fragilis Fresen. (Mucoraceae). These results suggest that the podophyllotoxin-synthesizing ability is obtained by uptaking genes involved in the podophyllotoxin synthesis from the host plant into endophytic fungal genomes.Conclusion: Our results showed, for the first time, that the endophytic fungus M. fragilis is able to produce simultaneously the same two bioactive metabolites, podophyllotoxin and kaempferol, as its host plant. Furthermore, the relatively high podophyllotoxin yield obtained may improve the industrial production of podophyllotoxin, which may help protect this endangered plant. 相似文献