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1.
《Saudi Pharmaceutical Journal》2022,30(11):1665-1671
5-fluorouracil (5FU) is widely used to treat colorectal cancer (CC) and its main mechanisms of anticancer action are through generation of ROS which often result in inflammation. Here, we test the effect of Lycopene against 5FU in Caco2 cell line. Caco2 cells were exposed to 3 µg/ml of 5FU alone or with 60, 90, 120 µg/ml of lycopene. This was followed by assessment of cytotoxicity, oxidative stress, and gene expression of inflammatory genes. Our findings showed that Lycopene and 5FU co-exposure induced dose-dependent cytotoxic effect without compromising the membrane integrity based on the LDH assay. Lycopene also significantly enhanced 5FU-induced SOD activity and GSH level compared to control for all mixture concentrations (p < 0.01). Lycopene alone and combination with 5FU-induced expression of IL-1β, TNF-α, and IL-6. Furthermore, IFN-γ expression was significantly enhanced by only mixture of lycopene (90 µg/ml) and 5FU (p < 0.05). In conclusion, Lycopene supplementation with 5FU therapy resulted in improvement in antioxidant parameters such as catalase and GSH levels giving the cell capacity to cope with 5FU-mediated oxidative stress. Lycopene also enhanced IFN-γ expression in the presence of 5FU, which may activate antitumor effects further enhancing the cancer killing effect of 5FU. 相似文献
2.
谷氨酰胺在危重病患者中的应用 总被引:3,自引:0,他引:3
目的探讨危重病患者中早期经静脉应用谷氨酰胺(glutamine,Gl)的临床价值。方法42例患者随机分成两组(对照组和Gln组),Gln组进行Gln治疗(100mL/d,共7d)。治疗前后检测患者体质量、白蛋白、谷胱甘肽(GSH)、握力的变化和肠功能不全的发生率。结果体质量两组治疗前后比较差异无显著性(P〉0.05)。白蛋白、握力和GSH Gl治疗后非常显著高于治疗前(P〈0.01);白蛋白对照组治疗后较治疗前显著增高(P〈0.05),但握力和GSH治疗前后均无显著变化(P〉0.05);肠功能不全的发生率Gln组为4.8%,显著低于对照组(28.6%,P〈0.05)。结论在危重病患者疾病早期通过静脉途径外源性地补充Gln,有效改善了患者的营养状况;使患者血浆中的GSH水平增高,加强了机体的抗氧化能力;减少了患者肠功能不全的发生率。 相似文献
3.
Measurements were made of glutathione (GSH) levels, catalase activity and the oxidant sensitivity of the erythrocytes from
the koala (Phascolarctos cinereus) and the common brushtail possum (Trichosurus vulpecula). The oxidant sensitivity was tested by treating the haemolysates with either 0.55 him H2O2 or 1.4mm NaNO2. The erythrocytes of the koala had greater levels of GSH and catalase and yet were found to be more susceptible to oxidation
induced by both these oxidants. 相似文献
4.
目的:为了解谷胱甘肽S-转移酶及其同工酶在原发性肝癌患者中的表达情况。方法:采用免疫组化方法对不同分化程度肝癌组织32例和肝硬化组织11例行GSTs和GST-π表达的研究,并以γ-GT作为对照;同时对128例不同肝病患者血清中GSTs活性作检测。结果:GSTs、GST-π及γ-GT的表达与肿瘤的分化程度有关,分化越差,阳性率越低,反之亦然;GST-π在分化良好组阳性表达率明显高于肝为后肝硬化组(P<0.05);血清GSTs活性检测肝癌组与正常对照组相比没有显著性差异(P>0.05)。结论:GST-π是优于γ-GT的肝癌标志酶,尤其在分化程度良好的肝癌,对临床区分肝癌的分化程度有一定的意义。 相似文献
5.
目的 研究异型增生程度不同的口腔白斑和不同分级的鳞癌中谷胱苷肽S转移酶π(GST π)的表达 ,探讨GST π在口腔鳞癌发生发展中的作用。 方法 采用免疫S -P法 ,对 5 4例轻、中、重度异型增生 ,4 7例高、中、低分化的口腔鳞癌 ,7例口腔粘膜上皮单纯增生患者组织进行GST π检测。 结果 口腔粘膜上皮单纯增生组织中未见GST π的表达 ,轻、中、重度异型增生病例中的GST π阳性率分别为4 7.8%、5 2 .9%和 6 4 .2 % ,高于单纯增生组 (P <0 .0 1) ;高分化鳞癌GST π阳性率为 6 4 .7% ,中、低分化鳞癌组分别为 2 8.5 %及 2 2 .2 % ,中、低分化鳞癌组表达均低于高分化鳞癌组及异型增生组 (P <0 .0 5 )。 结论 GST π表达的变化与口腔鳞癌早期的发生发展密切相关 相似文献
6.
Eri Ogawa Yuichiro Otsubo Norihiro Taira Nihal S. Agar 《Comparative clinical pathology》2005,13(3):137-141
Uptake of dehydroascorbic acid (DHA) was studied in two types of dog erythrocytes with high GSH and normal GSH levels. Compared with ascorbic acid uptake, DHA produced a much greater ascorbic acid accumulation in dog erythrocytes. Both dog erythrocytes showed a concentration dependence of DHA uptake, and cellular ascorbic acid concentrations were significantly higher in high-GSH cells than in normal-GSH cells. Glucose and cytochalasin B inhibited DHA uptake. This suggests that DHA enters dog erythrocytes predominantly by the facilitated glucose transporter, particularly by the Glut 1 glucose transporter. The rate of glucose uptake was quite similar in the two types of cells. Compared with normal-GSH cells, high-GSH cells were more resistant to oxidative stress induced by high concentration of DHA. As a rapid entry of DHA inflicts on cells a heavy demand for GSH for its reduction to ascorbic acid, high-GSH cells containing a larger reserve of GSH have an advantage over normal-GSH cells in both ascorbic acid accumulation and resisting oxidative stress produced by DHA. 相似文献
7.
8.
The cellular and regional distribution of glutathione (GSH) and GSH-related enzyme systems involved in cellular defense against reactive oxygen species and electrophilic xenobiotics in the nervous system has been extensively studied. However, little is known about the subcellular distribution of GSH systems in brain tissue and cultured neural cells. The present study investigates the distribution of mitochondrial and cytosolic GSH and GSH-related enzymes in cultured cerebellar astrocytes and granule cells, and compares them with levels in the adult rat cerebellum. Cytosolic GSH levels and cytosolic activities of glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) in astrocytes were 57, 153, 245, and 92% higher than those found in granule cells, respectively. In contrast, granule cells contained significantly higher mitochondrial GSH levels than astrocytes. Granule cells also demonstrated comparable mitochondria/cytosolic concentrations of GSH and GR, GPX and GST activities to those observed in the cerebellar tissue, whereas ratios in astrocytes were markedly lower. Although in vitro treatments with 100 μM ethacrynic acid depleted both cytosolic and mitochondrial GSH in cultured astrocytes and granule cells in a time-dependent fashion, cellular GSH in granule cells was more resistant to the GSH-depleting agent than astrocytes. These results suggest that although GSH and GSH-related enzymes are abundant in cytosolic compartments of astrocytes, mitochondrial pools are relatively small. Since brain mitochondria are sites of significant hydrogen peroxide generation, the mitochondrial localization of GSH and its associated enzymes in neural cells provide important defenses against toxic oxygen species in the nervous system. Differences in subcellular distribution of GSH systems in individual neural cell types may provide a basis for selective cellular and/or subcellular expression of neurotoxicity. 相似文献
9.
目的 探讨不同生长阶段长爪沙鼠血清中氧化与抗氧作用机制。方法 选择 1月龄、3月龄、2 4月龄的长爪沙鼠各 16只 (雌雄各半 ) ,测定长爪沙鼠血清中超氧化物歧化酶 (SOD)、丙二醛 (MDA)、谷胱甘肽过氧化物酶 (GsH -Px)。结果 丙二醛 (MDA)在 3月龄最低 ,谷胱甘肽过氧化物酶 (GsH -Px)在 3月龄最高 ;超氧化物歧化酶 (SOD)随着长爪沙鼠的月龄增长而升高。结论 在长爪沙鼠生长过程中谷胱甘肽过氧化物酶 (GsH -Px)的含量变化与丙二醛 (MDA)含量变化有直接关系 ,而超氧化物歧化酶 (SOD)含量变化与MDA含量变化没有直接关系。 相似文献
10.
以小麦(Triticum aestivum L.)品种石4185为材料,研究了45 ℃处理0~120 min对小麦未成熟籽粒谷甘胱肽转移酶(GST)、谷胱甘肽还原酶(GR)、过氧化氢酶(CAT)和过氧化物酶(POD)活性, 超微弱发光,种子萌发和愈伤组织诱导的影响.结果表明,热休克处理使未成熟籽粒萌发率、愈伤组织诱导率和GST活性明显增加,且其作用随处理时间的延长而增大;在处理过程中, CAT活性先减少后增加,热休克对GR活性无明显影响.GST的活性与蛋白质质量分数呈显著正相关. 相似文献