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91.
92.
Yin‐Hui Zhao Cai‐Fu Shen Guang‐Jun Wang Yan Kang Yun‐Hong Song Jiang‐Wei Liu 《Journal of biochemical and molecular toxicology》2021,35(1)
Curcumin exhibits anti‐inflammatory and antioxidant activities. We investigated the protective effects of curcumin in a renal injury rat model under dry‐heat conditions. We divided Sprague‐Dawley rats into four groups: dry‐heat 0‐ (normal temperature control group), 50‐, 100‐, and 150‐minute groups. Each group was divided into five subgroups (n = 10): normal saline (NS), sodium carboxymethylcellulose (CMCNa), and curcumin pretreated low, medium, and high‐dose (50, 100, and 200 mg/kg, respectively) groups. Compared to the normal temperature group, serum creatinine, blood urea nitrogen, urinary kidney injury molecule‐1, and neutrophil gelatinase‐associated load changes in lipoprotein (NGAL) levels were significantly increased in the dry‐heat environment group (P < .05); inducible nitric oxide synthase (iNOS) and cyclooxygenase‐2 (COX‐2) expression and malondialdehyde (MDA) and related inflammatory factor levels were increased in the kidney tissue. Superoxide dismutase (SOD) and catalase (CAT) levels were decreased. However, following all curcumin pretreatment, the serum levels of kidney injury indicators and NGAL were decreased in the urine compared to those in the NS and CMCNa groups (P < .05), whereas renal SOD and CAT activities were increased and MDA was decreased (P < .05). Renal tissues of the 150‐minute group showed obvious pathological changes. Compared to the NS group, pathological changes in the renal tissues of the 100‐ and 200‐mg/kg curcumin groups were significantly reduced. Furthermore, iNOS and COX‐2 expression and inflammatory factor levels were decreased after curcumin treatment. Curcumin exerted renoprotective effects that were likely mediated by its antioxidant and anti‐inflammatory effects in a dry‐heat environment rat model. 相似文献
93.
94.
Abigail R. Green Mark S. Nissen G.N. Mohan Kumar N. Richard Knowles ChulHee Kang 《The Plant cell》2013,25(12):5043-5052
Potato (Solanum tuberosum) multicystatin (PMC) is a unique cystatin composed of eight repeating units, each capable of inhibiting cysteine proteases. PMC is a composite of several cystatins linked by trypsin-sensitive (serine protease) domains and undergoes transitions between soluble and crystalline forms. However, the significance and the regulatory mechanism or mechanisms governing these transitions are not clearly established. Here, we report the 2.2-Å crystal structure of the trypsin-resistant PMC core consisting of the fifth, sixth, and seventh domains. The observed interdomain interaction explains PMC’s resistance to trypsin and pH-dependent solubility/aggregation. Under acidic pH, weakening of the interdomain interactions exposes individual domains, resulting in not only depolymerization of the crystalline form but also exposure of cystatin domains for inhibition of cysteine proteases. This in turn allows serine protease–mediated fragmentation of PMC, producing ∼10-kD domains with intact inhibitory capacity and faster diffusion, thus enhancing PMC’s inhibitory ability toward cysteine proteases. The crystal structure, light-scattering experiments, isothermal titration calorimetry, and site-directed mutagenesis confirmed the critical role of pH and N-terminal residues in these dynamic transitions between monomer/polymer of PMC. Our data support a notion that the pH-dependent structural regulation of PMC has defense-related implications in tuber physiology via its ability to regulate protein catabolism. 相似文献
95.
Hee Kyoung Kang Jung Han Suh Jung Jin Lee Sun Hee Yoon Jin Won Hyun Seong Won Choi 《Free radical research》2013,47(7):773-779
The present study was undertaken to examine the effect of l-ascorbic acid (LAA) on the growth of HL-60 promyelocytic leukemia cells, besides induction of apoptosis. LAA (≥10-4?M) was found to markedly inhibit the proliferation of HL-60 in liquid culture and clonogenicity in semisolid culture. Moreover, LAA-treated HL-60 showed activity to produce chemiluminescence and expressed CD 66b cell surface antigens, indicating that LAA induces the differentiation of HL-60 mainly into granulocytes. The results are supported by morphological changes of LAA-treated HL-60 into segmented neutrophils. Therefore, the inhibitory effect of LAA on the growth of HL-60 cells seems to arise from the induction of differentiation. To assess the potential role of LAA, cells were exposed to oxygen radical scavengers in the absence or presence of LAA. Catalase abolished and superoxide dismutase promoted LAA-induced differentiation of HL-60. Thus, H2O2 produced as a result of LAA treatment seems to play a major role in induction of HL-60 differentiation. 相似文献
96.
Jin Sil Chung Seung Baek Lee Seon Ho Park Sung Tae Kang Ah Ram Na Tong-Shin Chang 《Free radical research》2013,47(8):729-737
Reactive oxygen species (ROS) steady-state levels are required for entry into the S phase of the cell cycle in normal cells, as well as in tumour cells. However, the contribution of mitochondrial ROS to normal cell proliferation has not been well investigated thus far. A previous report showed that Romo1 was responsible for the high ROS levels in tumour cells. Here, we show that endogenous ROS generated by Romo1 are indispensable for cell cycle transition from G1 to S phase in normal WI-38 human lung fibroblasts. The ROS level in these cells was down-regulated by Romo1 knockdown, resulting in cell cycle arrest in the G1 phase. This arrest was associated with an increase in the level of p27Kip1. These results demonstrate that mitochondrial ROS generated by Romo1 expression is required for normal cell proliferation and it is suggested that Romo1 plays an important role in redox signalling during normal cell proliferation. 相似文献
97.
Heat shock may increase oxidative stress due to increased production of reactive oxygen species and/or the promotion of cellular oxidation events. Mitochondrial NADP+-dependent isocitrate dehydrogenase (IDPm) produces NADPH, an essential reducing equivalent for the antioxidant system. The protective role of IDPm against heat shock in HEK293 cells, an embryonic kidney cell line, was investigated in control and cells transfected with the cDNA for IDPm, where IDPm activity was 6–7 fold higher than that in the control cells carrying the vector alone. Upon exposure to heat shock, the viability was lower and the protein oxidation, lipid peroxidation and oxidative DNA damage were higher in control cells as compared to HEK293 cells in which IDPm was over-expressed. We also observed the significant difference in the cellular redox status reflected by the endogenous production of reactive oxygen species, NADPH pool and GSH recycling between two cells. The results suggest that IDPm plays an important role as an antioxidant defense enzyme in cellular defense against heat shock through the removal of reactive oxygen species. 相似文献
98.
Yochan Joung Haneul Kim Beom-Il Lee Heeyoung Kang Tae Yong Jang O-Seob Kwon Kiseong Joh 《Journal of microbiology (Seoul, Korea)》2013,51(4):531-535
A Gram-staining-negative, rod-shaped and red-pigmented bacterial strain, HMD3125T, was isolated from a solar saltern in Jeungdo, Republic of Korea. A phylogenetic tree based on 16S rRNA gene sequences showed that strain HMD3125T formed a lineage within the genus Pontibacter and was similar to Pontibacter salisaro (96.1%) and P. korlensis (95.3%). The major fatty acids of strain HMD3125T were summed feature 4 (comprising iso-C17:1 I and/or anteiso-C17:1 B; 30.4%), iso-C15:0 (20.4%) and iso-C17:0 3OH (17.2%). The polar lipid profile of HMD3125T consisted of the phosphatidylethanolamine, four unidentified polar lipids, unidentified phospholipid, unidentified aminolipid and unidentified aminophospholipid. Strain HMD3125T contained MK-7 as the predominant menaquinone and sym-homospermidine as the major polyamine. The DNA G+C content of strain HMD3125T was 45.6 mol%. Strain HMD3125T assigned as a novel species in the genus Pontibacter, for which the name Pontibacter jeungdoensis sp. nov. is proposed. The type strain is HMD3125T (=KCTC 23156T =CECT 7710T). 相似文献
99.
The physiological ecology of Prasiola stipitata was examined in situ from two supralittoral sites in the Bay of Fundy (Nova Scotian, Canada) during November 2011, when the population was undergoing major expansion. Photosynthetic parameters (effective quantum yield, ΦPSII, maximum quantum yield, Fv/Fm, and relative electron transport rate, rETR) were evaluated using chlorophyll fluorescence of PSII. A largely shaded and continuously moist population showed no change in ΦPSII from one hour after sunrise to sunset in which natural irradiance varied between 3 and 300 μmol photons m?2 s?1. High irradiance (up to 1800 μmol photons m?2 s?1) had no apparent negative impacts on either quantum yield or rETR, but high desiccation in the field reduced quantum yield to almost zero. When thalli were brought into the laboratory, no change in Fv/Fm was observed up to 60% dehydration; however, there was a steep decline in Fv/Fm between 60% and 85% dehydration. Thalli showed complete recovery of Fv/Fm within one hour of reimmersion in seawater after 2 days of desiccation. After 15 days of desiccation full recovery required 24 h and after 30 days of desiccation thalli showed only partial recovery. These observations confirm the adaptation to photosynthesis in high irradiances and the rapid recovery following extreme desiccation observed in other Prasiola species. 相似文献
100.
Lei Li Den-bang Chen Chao Lin Kang Cao Yang Wan Xin-yu Zhao Chun-lai Nie Zhu Yuan Yu-quan Wei 《Apoptosis : an international journal on programmed cell death》2013,18(4):467-479
PNAS-4, a novel pro-apoptotic gene, was activated during the early response to DNA damage. Previous studies have shown that hPNAS-4 can inhibit tumor growth when over-expressed in ovarian cancer cells. However, the underlying action mechanism remains elusive. In this work, we found that hPNAS-4 expression was significantly increased in SKOV3 cells when exposed to cisplatin, methyl methanesulfonate or mitomycin C, and that its overexpression could induce proliferation inhibition, S phase arrest and apoptosis in A2780s and SKOV3 ovarian cancer cells. The S phase arrest caused by hPNAS-4 was associated with up-regulation of p21. p21 is p53-dispensable and correlates with activation of ERK, and activation of the Cdc25A-Cdk2-Cyclin E/Cyclin A pathway, while the pro-apoptotic effects of hPNAS-4 were mediated by activation of caspase-9 and -3 other than caspase-8, and accompanied by release of AIF, Smac and cytochrome c into the cytosol. Taken together, these data suggest a new mechanism by which hPNAS-4 inhibits proliferation of ovarian cancer cells by inducing S phase arrest and apoptosis via activation of Cdc25A-Cdk2-Cyclin E/Cyclin A axis and mitochondrial dysfunction-mediated caspase-dependent and -independent apoptotic pathways. To our knowledge, we provide the first molecular evidence for the potential application of hPNAS-4 as a novel target in ovarian cancer gene therapy. 相似文献