scholarly journals Protective Effect of Low Molecular Weight Seleno-Aminopolysaccharide on the Intestinal Mucosal Oxidative Damage

Marine Drugs ◽  
2019 ◽  
Vol 17 (1) ◽  
pp. 64 ◽  
Author(s):  
Zheng-Shun Wen ◽  
Zhen Tang ◽  
Li Ma ◽  
Tian-Long Zhu ◽  
You-Ming Wang ◽  
...  

Low molecular weight seleno-aminopolysaccharide (LSA) is an organic selenium compound comprising selenium and low molecular weight aminopolysaccharide (LA), a low molecular weight natural linear polysaccharide derived from chitosan. LSA has been found to exert strong pharmacological activity. In this study, we aimed to investigate the protective effect of LSA on intestinal mucosal oxidative stress in a weaning piglet model by detecting the growth performance, intestinal mucosal structure, antioxidant indices, and expression level of intracellular transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) and its related factors. Our results indicated that LSA significantly increased the average daily gain and feed/gain (p < 0.05), suggesting that LSA can effectively promote the growth of weaning piglets. The results of scanning electron microscope (SEM) microscopy showed that LSA effectively reduced intestinal damage, indicating that LSA improved the intestinal stress response and protected the intestinal structure integrity. In addition, diamine oxidase (DAO) and d-lactic acid (d-LA) levels remarkably decreased in LSA group compared with control group (p < 0.05), suggesting that LSA alleviated the damage and permeability of weaning piglets. LSA significantly increased superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and total antioxidant capacity (T-AOC) levels, but decreased malondialdehyde (MDA) level, indicating that LSA significantly enhanced the antioxidant capacity and reduced oxidative stress in weaning piglets. RT-PCR results showed that LSA significantly increased GSH-Px1, GSH-Px2, SOD-1, SOD-2, CAT, Nrf2, HO-1, and NQO1 gene expression (p < 0.05). Western blot analysis revealed that LSA activated the Nrf2 signaling pathway by downregulating the expression of Keap1 and upregulating the expression of Nrf2 to protect intestinal mucosa against oxidative stress. Collectively, LSA reduced intestinal mucosal damage induced by oxidative stress via Nrf2-Keap1 pathway in weaning stress of infants.

2021 ◽  
Vol 18 ◽  
Author(s):  
Yuan Li ◽  
Lan Chu ◽  
Chunfeng Liu ◽  
Zongyi Zha ◽  
Yuanlu Shu

Aim: This study investigated the protective effect of dimethyl fumarate (DMF) in rats by mediating GSK3-β/Nrf2 using the middle cerebral artery embolization reperfusion (MCAO/R) rat model. Background: After an acute ischemic stroke (AIS), oxidative stress occurs. Dimethyl fumarate (DMF), a nuclear factor-E2-related factor 2 (Nrf2) activator, approved by the US Food and Drug Administration (FDA), was observed to regulate the Nrf2 pathway by acting as an anti-oxidative stress agent; however, whether this agent is involved in inhibiting GSK-3β remains to be established. Methods: DMF model was used to explore the effects of GSK-3β on Nrf2 expression level, Nrf2-ARE binding activity and Nrf2/ARE downstream expression level of anti-oxidant stress protein in Cerebral ischemia-reperfusion injury (CIRI). 60 rats were randomly divided into Sham group, MCAO/R group, solvent control group (DMSO group) and DMF treatment group, with 15 rats in each group. The MCAO/R, DMSO and DMF groups were considered in the MCAO/R model using the modified thread embolization method. In contrast, the Sham group was only anaesthetized and disinfected, and tissue muscle was dissected without inserting suture emboli. DMF group was gavaged with 45mg/kg per day of DMF, DMSO control group was gavaged with DMSO of equal volume, while MCAO/R group was only modeled without any intragastric treatment. The rats were treated seven days after the operation, and a neurological function Longa score was estimated. The rats were sacrificed seven days later, and the infarct volume was assessed by TTC staining. Hematoxylin-eosin (HE) staining was used to observe the pathological changes in rat brain tissue. Nissl staining was used to observe the expression of neurons in the infarcted cortex. Western blotting (WB) was used to observe the protein expression levels of glycogen synthase kinase 3β(GSK-3β), nuclear factor E2-related factor 2 (Nrf2), downstream heme oxygenase 1 (HO1) and NADPH quinone oxidoreductase 1 (NQO1) in four groups. The expression levels of GSK-3β and Nrf2 in the four groups were observed by immunohistochemistry and immunofluorescence. Results: (1) The Longa score of the MCAO/R, DMSO and DMF groups was found to be higher compared to the Sham group, indicating successful operation. The Longa score of the DMF group was lower than that of the other three groups 4-7 days after surgery (P<0.05). (2) HE and Nissl staining showed that the DMF group had lower neuron necrosis and higher gliosis compared to the control groups. (3) TTC staining results showed that the infarct volume of the DMF group was significantly smaller than the MCAO/R and DMSO groups. (4) Protein results showed that the GSK-3β expression in the DMF group was lower than that in all groups, while the expression of Nrf2, HO1 and NQO1 was higher compared to other groups. Conclusion: DMF can reduce neurological deficits and infarct size in the MCAO/R model. The protective effect may be related to decreased GSK-3β expression and increased Nrf2 expression, which may play a role in anti-oxidative stress.


Medicina ◽  
2019 ◽  
Vol 55 (6) ◽  
pp. 308 ◽  
Author(s):  
Ahmed Eleojo Musa ◽  
Dheyauldeen Shabeeb ◽  
Haider Saadoon Qasim Alhilfi

Background and Objectives: Radiation enteritis is a common side effect after radiotherapy for abdominal and pelvic malignancies. The aim of the present study was to investigate the protective effect of melatonin, known for its free radical scavenging ability, against radiotherapy-induced small intestinal oxidative damage. Materials and Methods: Thirty male Wistar rats were randomly assigned to six groups (5 rats in each) as follows: Group I (control group) rats received neither radiation nor melatonin; group II rats received only 8 Gy single dose of gamma radiation to their abdomen and pelvis regions; group III (administered with only 50 mg/kg melatonin); group IV (administered with only 100 mg/kg melatonin); group V (50 mg/kg melatonin + 8 Gy radiation), group VI (100 mg/kg melatonin + 8 Gy radiation). All rats were sacrificed after 5 days for biochemical assessments of their intestinal tissues. Results: Treatment with melatonin post irradiation significantly reduced malondialdehyde (MDA) levels as well as increased both superoxide dismutase (SOD) and catalase (CAT) activities of the irradiated intestinal tissues. In addition, melatonin administration with different doses pre irradiation led to protection of the tissues. Moreover, the 100 mg/kg dose was more effective compared to 50 mg/kg. Conclusions: The results of our study suggest that melatonin has a potent protective effect against radiotherapy-induced intestinal damage, by decreasing oxidative stress and increasing antioxidant enzymes. We recommend future clinical trials for more insights.


Biomolecules ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 380 ◽  
Author(s):  
Huang ◽  
Chang ◽  
Chau ◽  
Chiu

Hispidin, a polyphenol compound isolated from Phellinus linteus, has been reported to possess antioxidant activities. In this study, we aimed to investigate the mechanisms underlying the protective effect of hispidin against hydrogen peroxide (H2O2)-induced oxidative stress on Adult Retinal Pigment Epithelial cell line-19 (ARPE-19) cells. Hispidin was not cytotoxic to ARPE-19 cells at concentrations of less than 50 μM. The levels of intracellular reactive oxygen species (ROS) were analyzed by dichlorofluorescin diacetate (DCFDA) staining. Hispidin significantly restored H2O2-induced cell death and reduced the levels of intracellular ROS. The expression levels of antioxidant enzymes, such as NAD(P)H:Quinine oxidoreductase-1 (NQO-1), heme oxygenase-1 (HO-1), glutamate-cysteine ligase catalytic subunit (GCLC), and glutamate-cysteine ligase modifier subunit (GCLM) were examined using real-time PCR and Western blotting. Our results showed that hispidin markedly enhanced the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), HO-1, NQO-1, GCLM, and GCLC in a dose-dependent manner. Furthermore, knockdown experiments revealed that transfection with Nrf2 siRNA successfully suppresses the hispidin activated Nrf2 signaling in ARPE-19 cells. Moreover, activation of the c-Jun N-terminal kinase (JNK) pathway is involved in mediating the protective effects of hispidin on the ARPE-19 cells. Thus, the present study demonstrated that hispidin provides protection against H2O2-induced damage in ARPE-19 cells via activation of Nrf2 signaling and up-regulation of its downstream targets, including Phase II enzymes, which might be associated with the activation of the JNK pathway.


2019 ◽  
Vol 20 (22) ◽  
pp. 5727 ◽  
Author(s):  
Zheng-Shun Wen ◽  
Ming Du ◽  
Zhen Tang ◽  
Tian-Yi Zhou ◽  
Zhong-Shan Zhang ◽  
...  

Low molecular seleno-aminopolysaccharide (LSA) was synthesized with sodium selenite and low molecular aminopolysaccharide (LA), which is an organic selenium compound. This study is aimed to investigate the protective effect of LSA on the intestinal mucosal barrier in weaning stress rats by detecting the intestinal tissue morphology and function, mucosal thickness and permeability, the structure of MUC2, antioxidant index, the expression level of intracellular transcription factor NF-E2-related factor 2 (Nrf2), and its related factors. The results showed that LSA significantly increased the height of intestinal villi (p < 0.05) and increased the thickness of intestinal mucosa and the number of goblet cells, which indicated that LSA has a protective effect on the intestinal mucosal barrier that is damaged by weaning. Moreover, LSA significantly reduced the level of DAO, D-LA, and LPS compared with the weaning group (p < 0.05), which indicated that LSA reduced the intestinal damage and permeability of weaning rats. In addition, LSA could increase the number and length of glycans chains and the abundance of acid glycans structures in the MUC2 structure, which indicated that LSA alleviated the changes of intestinal mucus protein structure. LSA significantly increased the levels of GSH-Px, SOD, LDH, and CAT, while it decreased the level of MDA in serum and intestinal tissue, which suggested that LSA significantly enhanced the antioxidant capacity and reduced oxidative stress of weaning rats. RT-PCR results showed that LSA significantly increased the expression level of antioxidant genes (GSH-Px, SOD, Nrf2, HO-1), glycosyltransferase genes (GalNT1, GalNT3, GalNT7) and mucin gene (MUC2) in intestinal mucosa (p < 0.05). The results of western blot showed that the LSA activated the Nrf2 signaling pathway by down-regulating the expression of Keap1and up-regulating the expression of Nrf2, and protected the intestinal mucosa from oxidative stress. Overall, LSA could play a protective role in intestinal mucosal barrier of weaning rats by activating the Nrf2 pathway and alleviating the alnormal change of mucin MUC2.


2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Xinfeng Yu ◽  
Quanbin Zhang ◽  
Wentong Cui ◽  
Zheng Zeng ◽  
Wenzhe Yang ◽  
...  

Diabetic cardiomyopathy (DCM) is characterized by cardiac dysfunction and cardiomyocyte apoptosis. Oxidative stress is suggested to be the major contributor to the development of DCM. This study was intended to evaluate the protective effect of low molecular weight fucoidan (LMWF) against cardiac dysfunction in diabetic rats. Type 2 diabetic goto-kakizaki rats were untreated or treated with LMWF (50 and 100 mg/kg/day) for three months. The establishment of DCM model and the effects of LMWF on cardiac function were evaluated by echocardiography and isolated heart perfusion. Ventricle staining with H-E or Sirius Red was performed to investigate the structural changes in myocardium. Functional evaluation demonstrated that LMWF has a beneficial effect on DCM by enhancing myocardial contractility and mitigating cardiac fibrosis. Additionally, LMWF exerted significant inhibitory effects on the reactive oxygen species production and myocyte apoptosis in diabetic hearts. The depressed activity of superoxide dismutase in diabetic heart was also improved by intervention with LMWF. Moreover, LMWF robustly inhibited the enhanced expression of protein kinase Cβ, an important contributor to oxidative stress, in diabetic heart and high glucose-treated cardiomyocytes. In conclusion, LMWF possesses a protective effect against DCM through ameliorations of PKCβ-mediated oxidative stress and subsequent cardiomyocyte apoptosis in diabetes.


2003 ◽  
Vol 22 (5) ◽  
pp. 229-235 ◽  
Author(s):  
P R Deepa ◽  
P Varalakshmi

The present study is aimed to demonstrate the protective effect of a heparin derivative, low molecular weight heparin (LMWH) against erythrocyte membrane injury. Two models serve to induce membrane lipid peroxidative damage, namely a potent cytotoxic agent, adriamycin and a hypercholesterolemic atherogenic diet. Two groups of male Wistar rats (1409-10 g) received a single intravenous injection of adriamycin (ADR, 7.5 mg/kg), while two other groups were fed an atherogenic diet comprising a supplementation of 4% cholesterol, 1% cholic acid and 0.5% thiouracil (CCT diet) for 2 weeks. For each of the above two groups, LMWH (Troparin; 300 mg/day per rat subcutaneously) treatment commenced on day 8 and continued for a week. One group was maintained as the normal control group, and another group that received only LMWH treatment was designated as the LMWH drug control group. Erythrocyte membrane was isolated and assayed for its cholesterol levels, lipid peroxidation and ATPases activity. The activities of antioxidant enzymes were assessed in the haemolysate. The findings of the study were that both adriamycin and the atherogenic diet produced elevated membrane cholesterol levels and lipid peroxidation. The membrane ATPases suffered loss in activity. Accentuated oxidative stress was marked by rise in the activities of antioxidant enzymes (SOD, catalase and GPx). LMWH intervention reverted these changes thereby normalizing the membrane composition and function. The membrane protective effect of LMWH is illuminated by this work.


Antioxidants ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 340 ◽  
Author(s):  
Ilekuttige Priyan Shanura Fernando ◽  
Mawalle Kankanamge Hasitha Madhawa Dias ◽  
Disanayaka Mudiyanselage Dinesh Madusanka ◽  
Eui Jeong Han ◽  
Min Ju Kim ◽  
...  

Ultraviolet B (UVB) radiation-induced oxidative skin cell damage is a major cause of photoaging. In the present study, a low molecular weight fucoidan fraction (SHC4) was obtained from Sargassum horneri by Celluclast-assisted extraction, followed by step gradient ethanol precipitation. The protective effect of SHC4 was investigated in human keratinocytes against UVB-induced oxidative stress. The purified fucoidan was characterized by Fourier-transform infrared spectroscopy (FTIR), 1H nuclear magnetic resonance (NMR), agarose gel-based molecular weight analysis and monosaccharide composition analysis. SHC4 had a mean molecular weight of 60 kDa, with 37.43% fucose and 28.01 ± 0.50% sulfate content. The structure was mainly composed of α-L-Fucp-(1→4) linked fucose units. SHC4 treatment dose-dependently reduced intracellular reactive oxygen species (ROS) levels and increased the cell viability of UVB exposed HaCaT keratinocytes. Moreover, SHC4 dose-dependently inhibited UVB-induced apoptotic body formation, sub-G1 accumulation of cells and DNA damage. Inhibition of apoptosis was mediated via the mitochondria-mediated pathway, re-establishing the loss of mitochondrial membrane potential. The UVB protective effect of SHC4 was facilitated by enhancing intracellular antioxidant defense via nuclear factor erythroid 2–related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling. Further studies may promote the use of SHC4 as an active ingredient in cosmetics and nutricosmetics.


1997 ◽  
Vol 77 (01) ◽  
pp. 057-061 ◽  
Author(s):  
Dennis W T Nilsen ◽  
Lasse Gøransson ◽  
Alf-Inge Larsen ◽  
Øyvind Hetland ◽  
Peter Kierulf

SummaryOne hundred patients were included in a randomized open trial to assess the systemic factor Xa (FXa) and thrombin inhibitory effect as well as the safety profile of low molecular weight heparin (LMWH) given subcutaneously in conjunction with streptokinase (SK) in patients with acute myocardial infarction (MI). The treatment was initiated prior to SK, followed by repeated injections every 12 h for 7 days, using a dose of 150 anti-Xa units per kg body weight. The control group received unfractionated heparin (UFH) 12,500 IU subcutaneously every 12 h for 7 days, initiated 4 h after start of SK infusion. All patients received acetylsalicylic acid (ASA) initiated prior to SK.Serial blood samples were collected prior to and during the first 24 h after initiation of SK infusion for determination of prothrombin fragment 1+2 (Fl+2), thrombin-antithrombin III (TAT) complexes, fibrinopeptide A (FPA) and cardiac enzymes. Bleeding complications and adverse events were carefully accounted for.Infarct characteristics, as judged by creatine kinase MB isoenzyme (CK-MB) and cardiac troponin T (cTnT), were similar in both groups of patients.A comparable transient increase in Fl+2, TAT and FPA was noted irrespective of heparin regimen. Increased anti-Xa activity in patients given LMWH prior to thrombolytic treatment had no impact on indices of systemic thrombin activation.The incidence of major bleedings was significantly higher in patients receiving LMWH as compared to patients receiving UFH. However, the occurrence of bleedings was modified after reduction of the initial LMWH dose to 100 anti-Xa units per kg body weight.In conclusion, systemic FXa- and thrombin activity following SK-infusion in patients with acute MI was uninfluenced by conjunctive LMWH treatment.


2020 ◽  
Vol 18 (3) ◽  
pp. 260-265
Author(s):  
Xu Lin ◽  
Zheng Xiaojun ◽  
Lv Heng ◽  
Mo Yipeng ◽  
Tong Hong

The purpose of this study was to evaluate the protective effect of swertiamarin on heart failure. To this end, a rat model of heart failure was established via left coronary artery ligation. Infarct size of heart tissues was determined using triphenyl tetrazolium chloride staining. Echocardiography was performed to evaluate cardiac function by the determination of ejection fraction, left ventricular internal dimension in diastole and left ventricular internal dimension in systole. The effect of swertiamarin on oxidative stress was evaluated via enzyme-linked immunosorbent assay. The mechanism was evaluated using western blot. Administration of swertiamarin reduced the infarct size of heart tissues in rat models with heart failure. Moreover, swertiamarin treatment ameliorated the cardiac function, increased ejection fraction and fractional shortening, decreased left ventricular internal dimension in diastole and left ventricular internal dimension in systole. Swertiamarin improved oxidative stress with reduced malondialdehyde, while increased superoxide dismutase, glutathione, and GSH peroxidase. Furthermore, nuclear-factor erythroid 2-related factor 2, heme oxygenase and NAD(P)H dehydrogenase (quinone 1) were elevated by swertiamarin treatment in heart tissues of rat model with heart failure. Swertiamarin alleviated heart failure through suppression of oxidative stress response via nuclear-factor erythroid 2-related factor 2/heme oxygenase-1 pathway providing a novel therapeutic strategy for heart failure.


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