Oxidative Stress Response In Rats Research Articles

Proteomics reveals that Di Dang decoction can regulate the Jak2/Stat5 signaling pathway and inhibit apoptosis by reducing the oxidative stress response in rats with acute intracerebral hemorrhagic stroke

Ethnopharmacological relevanceDi Dang decoction (DDD) is a prescription used for the treatment of cerebral hemorrhage. Its use is derived from the theory of typhoid fever, it has an obvious clinical effect and it has been used in the clinic for a long time. The results of early quantitative proteomics and targeted proteomics studies showed that the administration of high-dose DDD 7 days may regulate the expression of the proteins S100A8, S100A9, Col1a1 and Col1a2. The first 3 days after bleeding begins is the critical period for intervention, what occurs within approximately 3 days after AICH is unclear. Aim of the studyTo explore the effects of Di Dang decoction (DDD) on the Jak2/Stat5 signaling pathway and apoptosis-related gene expression in rats with acute hemorrhagic stroke via the oxidative stress response by proteomics to reveal its neuroprotective mechanism. Materials and methodsNinety healthy Sprague–Dawley (SD) rats were randomly divided into the control, model, and low-, medium-, and high-dose DDD groups, with 18 rats in each group. An acute intracerebral hemorrhage (AICH) model was established by injecting autologous blood into the caudate nucleus. The low-, medium- and high-dose groups were intragastrically administered 0.15625 g/mL, 0.3125 g/mL and 0.625 g/mL DDD, respectively, for 1 or 3 days. The control and model groups were given the same amount of normal saline. Neurological deficits were evaluated by the modified neurological severity score (mNSS) test, brain water content was measured to assess brain tissue damage, and pathological changes in the lesion site were observed by hematoxylin and eosin (HE) staining. The cerebral cortex was selected for quantitative proteomics, and >1.2/1 and <1/1.2 were used as the thresholds for upregulated and downregulated proteins, respectively. KEGG pathway and Gene Ontology (GO) enrichment analyses of the differentially expressed proteins were conducted. The levels of the oxidative stress markers malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) were measured by enzyme-linked immunosorbent assay (ELISA). Western blotting was used to assess p-Jak2, Jak2, p-Stat5, Stat5, Bax, Bcl-2, and Caspase-3 protein expression. ResultsCompared with the model group, the group treated with high-dose DDD for 3 days exhibited significant improvements in neurological defects, brain histopathology, and brain edema; reduced the level of MDA and significantly increased the levels of CAT and SOD; significantly decreased p-Jak2 and p-Stat5 protein expression and expression of the pro-apoptotic genes Bax and c-Caspase-3; and significantly increased expression of the anti-apoptotic gene Bcl-2 (all p＜0.05). ConclusionsHigh-dose DDD administration for 3 days reduces the oxidative stress response, regulates the Jak2/Stat5 signaling pathway and inhibits apoptosis to exert a neuroprotective effect in rats with acute hemorrhagic stroke.

Diammonium glycyrrhizinate nanoliposomes impede tumor necrosis factor-α pathway to affect oxidative stress response in rats with ulcerative colitis

Ulcerative colitis (UC) is a inflammatory disease. Herein we explored the impact of diammonium glycyrrhizinate (DG)-nanoliposomes on inflammation and oxidative stress in rats. DG-nanoliposomes were prepared, and the rats with UC were grouped into nanoliposome group, DG group, DG-nanoliposome group and blank group. Then we quantified the levels of IL-8, IL-6, IL-1β, TNF-α and Lactoperoxidase (LPO) in rats from each group by tissue biochemistry staining, and the protein levels of NF-κB p65 were detected by Western Blot (WB). The drug-loading capacity and efficiency of DG-nanoliposomes were 27.0% and 52.0%, respectively. A significantly increased Zeta potential was recorded in the DG-nanoliposomes compared to the unloaded nanoliposomes (P &lt;0.05). The expression of IL-8, IL-6, IL-1β, TNF-α and LPO in rats receiving DG-nanoliposome s were remarkably lower than those receiving other treatments (P &lt;0.05). A significant reduction of NF-κB p65 was detected in the samples from the DG-nanoliposome group compared to those receiving other treatments (P &lt;0.05). In this study, DG-nanoliposomes were prepared and used for UC treatment in rats. The results proved that DG-nanoliposomes can regulate oxidative stress by inhibiting the TNF-α signaling pathway. Eventually, TNF-α, IL-8, IL-6, IL-1β, LPO and NF-κB p65 in UC rats were reduced, thereby improving the curative effect of DG-nanoliposomes on UC rats. However, some potential limitations still exist in this study, including the insufficient sample size and the limitation of the animal experiment. Despite limitations, DG-nanoliposomes are still a promising strategy in the field of UC therapy with great potential for clinical translation.

Effects of miR-145-5p on cardiomyocyte proliferation and apoptosis, GIGYF1 expression and oxidative stress response in rats with myocardial ischemia-reperfusion.

This study aimed to investigate the effects of miR-145-5p on cardiomyocyte proliferation and apoptosis, GIGYF1 expression, inflammation, and oxidative stress in rats with myocardial ischemia-reperfusion injury (IRI). For this purpose, SPF male SD rats were used for IRI modeling. Experimental animals were subjected to specimen sampling and myocardial HE staining. The relative expression of miR-145-5p was detected by qRT-PCR; the protein expressions of GIGYF1, p-AKT, p53, Bax, p38MAPK, and ERK1/2 were detected by Western blot. Mouse embryonic cardiomyocytes H9C2 were used for H/R modeling, which was then subjected to cell transfection according to different grouping protocols. The target of miR-145-5p was confirmed to be GIGYF1 by dual-luciferase reporter assay. Further experiments were performed to detect the survival rate of transfected cells, the apoptosis of transfected cells, SOD activity determination, as well as IL-1β and IL-6 concentrations. The results showed that the expression level of miR-145-5p was downregulated in H2C2 cells (P < 0.05). After 24h of transfection, there was a significant increase in the expression of miR-145-5p in the H/R+miR-145-5p mimic group (P < 0.05), but an evident decrease in the H/R+miR-145-5p inhibitor group (P > 0.05). Compared with the H/R+NC inhibitor group, the H/R+miR-145-5p mimic group had significantly increased cell proliferation, improved release of SOD, and upregulated expressions of ERK1/2 and p-AKT; but downregulated concentrations of IL-1β and IL-6, and decreased expressions of P38MAPK, p53, and Bax (all P < 0.05). Also, the IRI+miR-145-5p agomir group had significantly upregulated expression of miR-145-5p and improved injury degree of heart tissue improved; a significant increase in the protein expressions ERK1/2 and p-AKT, but downregulated protein expressions of P38MAPK, p53, and Bax (all P < 0.05). Dual-luciferase reporter assay identified that GIGYF1 was the target gene of miR-145-5p. Furthermore, through the stimulated overexpression of miR-145-5p, there were significantly increased cell proliferation, improved release of SOD, and upregulated expressions of ERK1/2 and p-AKT; but downregulated concentrations of IL-1β and IL-6, and decreased expressions of P38MAPK, p53, and Bax (all P < 0.05), while the above trends were reversed following the simultaneous upregulation of miR-145-5p and GIGYF1 (all P < 0.05). In general, our study confirmed a decreased expression of miR-145-5p and increased expression of GIGYF1 in the IRI or H/R model in vivo and in vitro. Overexpression of miR-145-5p can downregulate the expression of GIGYF1, further promote cell proliferation, inhibit cell apoptosis, alleviate inflammation and oxidative stress, and hence exert a protective role in myocardial infarction IRI.

Proteomics Reveals that Di Dang Decoction Can Regulate the Jak2/Stat5 Signaling Pathway and Inhibit Apoptosis by Reducing the Oxidative Stress Response in Rats with Acute Intracerebral Hemorrhagic Stroke

Proteomics Reveals that Di Dang Decoction Can Regulate the Jak2/Stat5 Signaling Pathway and Inhibit Apoptosis by Reducing the Oxidative Stress Response in Rats with Acute Intracerebral Hemorrhagic Stroke

The Effect of Noise in the Intensive Care Unit on the Oxidative Stress Response in Rats.

The objective of this study was to determine the effect of noise in the intensive care unit (ICU) on oxidative stress in a rat model. This study had both a descriptive and a randomized controlled experimental stage. In the descriptive stage, to create a laboratory model of noise in the ICU, the noise level was measured for 24 hr on a randomly selected day in a surgical ICU, and voice recording was performed using a sound recording device. In the experimental stage, 30 male Wistar albino rats were randomly divided into 5 groups: a control group and groups exposed to the recording of the noise from the ICU for 24, 48, 72, and 168 hr. The noise level in the ICU was higher than the levels recommended for hospitals. Plasma corticosterone levels of the rats in the group exposed to the ICU noise for 168 hr were significantly higher than those of the control group. Plasma total protein values were significantly reduced in the rats exposed to 48, 72, and 168 hr of ICU noise compared to those of the control group. Superoxide dismutase activity was significantly decreased and malondialdehyde levels significantly increased in serum, spleen, and brain tissues as the duration of noise exposure increased. Findings reveal that rats experienced increasing levels of stress and oxidative stress as time exposed to the ICU noise increased. These results suggest that interventions to reduce noise in the ICU may be warranted.

Role of PI3K/Akt signaling pathway in propofol-induced reduction of intestinal ischemia-reperfusion injury in rats

Objective To evaluate the role of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway in propofol-induced reduction of intestinal ischemia-reperfusion (I/R) injury in rats. Methods Thirty-two healthy male Sprague-Dawley rats, aged 2-3 months, weighing 225-275 g, were divided into 4 groups (n=8 each) using a random number table method: sham operation group (Sham group), intestinal I/R group (I/R group), propofol group (P group), and PI3K inhibitor wortmannin plus propofol group (W+ P group). Intestinal ischemia was induced by occluding the superior mesenteric artery for 45 min followed by 2 h of reperfusion to establish the model of intestinal I/R injury.Propofol was intravenously infused at a rate of 20 mg·kg-1·h-1 starting from the onset of reperfusion until the end of reperfusion in group P. Wortmannin 15 μg/kg was intravenously injected at 25 min before reperfusion, and propofol was intravenously infused at a rate of 20 mg·kg-1·h-1 starting from the onset of reperfusion until the end of reperfusion in group W+ P.Rats were sacrificed at 2 h of reperfusion, and small intestinal tissues were obtained for microscopic examination of pathologic changes of intestinal mucosa and for determination of wet/dry weight ratio (W/D ratio), malondialdehyde (MDA) content (by thiobarbituric acid colorimetric method), superoxide dismutase (SOD) activity (using xanthine oxidase method), myeloperoxidase (MPO) activity (by MPO assay), and phosphorylated Akt (p-Akt) expression (by Western blot). Intestinal damage was assessed and scored according to Chiu. Results Compared with group Sham, Chiu′s score, W/D ratio, MDA content and MPO activity were significantly increased, the SOD activity was decreased, and p-Akt expression was down-regulated in group I/R (P<0.05). Compared with group I/R, Chiu′s score, W/D ratio, MDA content and MPO activity were significantly decreased, the SOD activity was increased, and p-Akt expression was up-regulated in group P (P<0.05). Compared with group P, Chiu′s score, W/D ratio, MDA content and MPO activity were significantly increased, the SOD activity was decreased, and p-Akt expression was down-regulated in group W+ P (P<0.05). Conclusion The mechanism by which propofol reduces intestrnal I/R injury is related to activating PI3K/Akt signaling pathway and inhibiting inflammatory and oxidative stress responses in rats. Key words: Propofol; Reperfusion injury; Intestines; Phosphatidylinositol 3-kinase; Protein kinases

Neutrophil elastase inhibitor suppresses oxidative stress in obese asthmatic rats by activating Keap1/Nrf2 signaling pathway.

The aim of this study was to detect the oxidative stress response in the rat model of obesity, asthma and obese asthma. Meanwhile, we aimed to investigate the inhibitory effect of neutrophil elastase inhibitor (NEI) on cellular oxidative stress in the body and whether it exerted an effect on the oxidative stress response in obese asthma through the Kelch-like ECH-associated protein 1/nuclear factor E2-related factor 2 (Keap1/Nrf2) pathway. The obesity and asthma models were established using a total of 70 Sprague-Dawley (SD) rats. All rats were randomly divided into 7 groups. The rats with normal weight were divided into the control (CTR) group (n=10), asthma (ATM) group (n=10) and ATM+NEI group (n=10). Meanwhile, the obese rats were divided into the obesity (OBS) group (n=10), the OBS+NEI group (n=10), the OBS+ATM group (n=10) and the OBS+ATM+NEI group (n=10). After modeling, rats in NEI intervention groups were injected with Sivelestat (5 mg/kg) via the caudal vein twice a day for 1 week. The tests of cough sensitivity to capsaicin and bronchial responsiveness were performed 24 h after the last administration. Lung tissues of rats were collected for hematoxylin-eosin (HE) staining. Meanwhile, the levels of reactive oxygen species (ROS) in heart, lung and kidney tissues were detected via 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA). The activities of reduced glutathione (GSH), glutathione peroxidase (GSH-Px), H2O2 and total superoxide dismutase (T-SOD) in the heart, lung and kidney tissues were detected using the colorimetric method. The mRNA and protein expressions of Keap1 and Nrf2 messenger ribonucleic acid expressions in the heart, lung and kidney tissues were measured via Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and Western blotting, respectively. NEI significantly improved the symptoms and lung pathology in rats with asthma. The level of ROS in the heart, lung and kidney tissues of the OBS group, ATM group and OBS+ATM group was significantly increased. However, NEI markedly inhibited the level of ROS in rats with asthma. The activities of antioxidant stress-related enzymes (reduced GSH, GSH-Px, H2O2 and SOD) in the heart, lung and kidney tissues of the OBS group, ATM group and OBS+ATM group were significantly decreased. However, NEI markedly promoted the activities of the related antioxidant enzymes in oxidative stress response in asthma rats. Besides, the Keap1/Nrf2 signaling pathway in the heart, lung and kidney tissues of the OBS group, ATM group and OBS+ATM group was significantly inhibited, while NEI activated the Keap1/Nrf2 signaling pathway in rats with asthma. NEI promotes the release of a variety of antioxidant factors, enhances the activity of antioxidant enzymes and improves the symptoms of rats with obese asthma. The possible underlying mechanism may be the activation of the Keap1/Nrf2 signaling pathway.

Chronopharmacological effects of growth hormone on the executive function and oxidative stress response in rats.

Objective(s):To investigate the chronopharmacological effects of growth hormone on executive function and the oxidative stress response in rats.Materials and Methods:Fifty male Wistar rats (36-40 weeks old) had ad libitum access to water and food and were separated into four groups: diurnal control, nocturnal control, diurnal GH-treated, and nocturnal GH-treated animals. Levels of Cu, Zn superoxide dismutase (Cu, Zn-SOD), and superoxide release by spleen macrophages were evaluated. For memory testing, adaptation and walking in an open field platform was used. GH-treated animals demonstrated better performance in exploratory and spatial open-field tests.Results:The latency time in both GH-treated groups was significantly lower compared with the latency time of the control groups. The diurnal GH treatment did not stimulate superoxide release but increased the CuZn-SOD enzyme levels. The nocturnal GH treatment did not influence the superoxide release and CuZn-SOD concentration. GH treatment also resulted in heart atrophy and lung hypertrophy.Conclusion:Growth hormone treatment improved the performance of executive functions at the cost of oxidative stress triggering, and this effect was dependent on the circadian period of hormone administration. However, GH treatment caused damaging effects such as lung hypertrophy and heart atrophy.

Ochratoxin A induces karyomegaly and cell cycle aberrations in renal tubular cells without relation to induction of oxidative stress responses in rats

Ochratoxin A (OTA) is a renal carcinogen that induces karyomegaly in target renal tubular cells of the outer stripe of the outer medulla (OSOM). This study was performed to clarify the relationship between oxidative stress and the karyomegaly-inducing potential involving cell cycle aberration of OTA in the OSOM. Rats were treated with OTA for 28 days in combination with enzymatically modified isoquercitrin (EMIQ) or α-lipoic acid (ALA) as antioxidants. OTA increased the mRNA levels of the antioxidant enzyme-related genes Gpx1, Gpx2, Gstm1 and Nfe2l2, but did not increase the levels of Gsta5, Keap1, Nqo1, Hmox1, Aldh1a1, Por, Prdx1 and Txn1. OTA also did not change the levels of thiobarbituric acid-reactive substances, glutathione disulfide/reduced glutathione, and the immunoreactive tubular cell distribution of nuclear factor erythroid 2-related factor 2 in the OSOM. Co-treatment with EMIQ or ALA did not cause any changes in these parameters. As previously reported, OTA increased cell proliferation activity, apoptosis and immunohistochemical cellular distributions of molecules suggestive of induction of DNA damage and cell cycle aberrations involving spindle checkpoint disruption and cell cycle arrest. However, co-treatment with EMIQ or ALA did not suppress these changes, and ALA co-treatment increased the cell proliferation activity induced by OTA. These results suggest that OTA facilitates cell cycling involving cell cycle aberrations and apoptosis as a basis of the mechanism behind the development of karyomegaly and subsequent carcinogenicity targeting the OSOM, without relation to induction of oxidative stress. On the other hand, ALA may promote the OTA-induced proliferation of carcinogenic target cells.

Concomitant apoptosis and regeneration of liver cells as a mechanism of liver-tumor promotion by β-naphthoflavone involving TNFα-signaling due to oxidative cellular stress in rats

β-Naphthoflavone (BNF) is a strong inducer of cytochrome P450 1A enzymes, and exerts liver tumor-promoting activity through enhancement of oxidative stress responses in rats. This study investigated the role of the tissue environment surrounding hepatocellular preneoplastic lesions in the early tumor-promotion stage by BNF, using enzymatically modified isoquercitrin (EMIQ) as an anti-oxidative chemopreventive agent. Male F344 rats were fed a diet containing BNF (0.5%) for 6 weeks, with or without EMIQ (0.2%) in the drinking water, 2 weeks after initiation with N-diethylnitrosamine, and were subjected to two-thirds partial hepatectomy 1 week after starting BNF-promotion. BNF-treatment increased concentrations of liver thiobarbituric acid-reactive substances, single liver cells expressing glutathione S-transferase placental form or heme oxygenase (HO)-1, and concomitant apoptosis and proliferation of liver cells. Transcript upregulation of anti-oxidative enzymes ( Aldh1a1 and Nqo1), cell cycle-related molecules ( Cdc20 and Cdkn2b) and inflammation-related molecules including proinflammatory cytokines ( Ccl2, Col1a1, Il6, Nos2 and Serpine1) was also evident. Furthermore, BNF increased HO-1-expressing Kupffer cells and liver cells expressing tumor necrosis factor receptor 1 (TNFR1) and the TNFR1-associated death domain. Most of these BNF-induced fluctuations disappeared or were suppressed by EMIQ in conjunction with suppression of tumor-promotion. Tnf transcript levels with BNF were also suppressed by EMIQ. These results suggest that BNF-induced oxidative stress causes single liver cell toxicity, allowing subsequent concomitant apoptosis and regeneration involving inflammatory responses including TNFα-signaling, contributing to tumor promotion. Kupffer cells may act to protect against inflammatory stimuli induced as a result of oxidative cellular stress by BNF, causing proinflammatory cytokine level fluctuations.

Relationship between CYP1A induction by indole-3-carbinol or flutamide and liver tumor-promoting potential in rats

To investigate liver tumor-promoting potentials of indole-3-carbinol (I3C) and flutamide (FLU), changes in mRNA expression of Cyp1a and genes encoding antioxidant/detoxifying enzymes in the liver, 6-week-old male F344 rats were subjected to medium-term liver bioassay. β-Naphthoflavone (BNF), a strong CYP1A inducer, was also used for comparison. Two weeks after initiation with N-diethylnitrosamine (DEN), animals were fed a basal diet (untreated controls) or a diet containing 0.5% I3C, 0.1% FLU, or 0.5% BNF for 6weeks. Each animal was subjected to a two-third partial hepatectomy 1week after the start of promoter treatments. Histopathologically, I3C and BNF increased altered liver cell foci with the incidence (3.7- and 7.3-fold) and multiplicity (8.3- and 13.8-fold) compared with the DEN-alone group, respectively. Immunohistochemically, I3C significantly increased the number (3.1-fold; P<0.01) and area (2.4-fold; P<0.05) of foci positive for glutathione-S-transferase placental form (GST-P) compared with the DEN-alone group; FLU induced a slight but significant increase in the number of GST-P-positive foci (2.8-fold; P<0.05) whereas BNF showed marked induction of the number and area of GST-P-positive foci (20- and 14-fold, respectively; P<0.01). In parallel, I3C, FLU, and BNF markedly increased mRNA levels of Cyp1a1 (50-, 23-, 299-fold) and antioxidant/detoxifying enzymes such as Gpx2 and Nqo1 as shown by real-time reverse transcription-polymerase chain reaction analysis. These results suggest that I3C and FLU could promote hepatocellular tumors in parallel with that of CYP1A's potential to cause subsequent oxidative stress responses in rats.