scholarly journals Establishment of a New Arrhythmia Model in SD Rats Induced by the Isoproterenol "6+1" Mode and Its Mechanisms

Author(s):  
ZiJing Guo ◽  
ZhiChao Wang ◽  
KeXin Ma ◽  
Baozhu Ding ◽  
GuoPing Ma ◽  
...  

Abstract BackgroundThe main purpose is to establish an ideal arrhythmia model with isoproterenol and explore its mechanism.MethodsFifty healthy male SD rats were randomly divided into the control (CON) group, subcutaneous injection (SC) group(ISO 5 mg/kg for 2 consecutive days), intraperitoneal injection (IP) group (ISO 5 mg/kg for 2 consecutive days), 2+1 group (ISO 5mg/kg by SC for 2 consecutive days, then ISO 3mg /kg by IP for 1 day), 6+1 group ( ISO 5mg/kg by SC for 6 consecutive days, then ISO 3mg /kg by IP for 1 day).The ECG were recorded by BL-420F system. The pathological changes in myocardial tissue were observed by HE and Masson staining. The serum cTnI, TNF-α, IL-6, and IL-1β levels were detected by ELISA. Serum CK, LDH and oxidative stress-related indicators were detected by an automatic biochemical analyser. ResultsThe cardiomyocytes in the CON group rats were normal, while those in the other groups showed signs of disorder, unclear borders, and lysis and necrosis, especially in the 6+1 group. The incidence of arrhythmia, arrhythmia score, and the levels of serum myocardial enzymes, troponin, and some inflammatory factors in the 2+1 group and 6+1 group were higher than those in the single injection way (P<0.01 or P<0.05). The indicators in the 6+1 group were mostly higher than those in the 2+1 group (P<0.01), and the SOD level in the 6+1 group was lower than that in the CON group; the MDA and NO higher(P<0.01 or P<0.05). ConclusionThe combined mode of ISO injection (SC with IP) is more likely to induce arrhythmia than single ISO injection. The "6+1" method of ISO injection can establish a more stable arrhythmia model. Cardiomyocyte damage induced by oxidative stress and inflammation is an important mechanism.

2019 ◽  
Vol 35 (1) ◽  
Author(s):  
Ju-Bin Kang ◽  
Dong-Ju Park ◽  
Murad-Ali Shah ◽  
Myeong-Ok Kim ◽  
Phil-Ok Koh

Abstract Lipopolysaccharide (LPS) acts as an endotoxin, releases inflammatory cytokines, and promotes an inflammatory response in various tissues. This study investigated whether LPS modulates neuroglia activation and nuclear factor kappa B (NF-κB)-mediated inflammatory factors in the cerebral cortex. Adult male mice were divided into control animals and LPS-treated animals. The mice received LPS (250 μg/kg) or vehicle via an intraperitoneal injection for 5 days. We confirmed a reduction of body weight in LPS-treated animals and observed severe histopathological changes in the cerebral cortex. Moreover, we elucidated increases of reactive oxygen species and oxidative stress levels in LPS-treated animals. LPS administration led to increases of ionized calcium-binding adaptor molecule-1 (Iba-1) and glial fibrillary acidic protein (GFAP) expression. Iba-1 and GFAP are well accepted as markers of activated microglia and astrocytes, respectively. Moreover, LPS exposure induced increases of NF-κB and pro-inflammatory factors, such as interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α). Increases of these inflammatory mediators by LPS exposure indicate that LPS leads to inflammatory responses and tissue damage. These results demonstrated that LPS activates neuroglial cells and increases NF-κB-mediated inflammatory factors in the cerebral cortex. Thus, these findings suggest that LPS induces neurotoxicity by increasing oxidative stress and activating neuroglia and inflammatory factors in the cerebral cortex.


Author(s):  
Min Dai ◽  
◽  
Cheng Peng ◽  

Methicillin-Resistant Staphylococcus Aureus (MRSA) is one of the most serious health concerns bacterial owing to its incidence and the severity of the associated infections. It is necessary to find new chemical compounds with anti-MRSA activity. A model of MRSA infection was prepared by intraperitoneal injection of MRSA. A. tasao-ko essential oil was used for pretreatment and treatment of MRSA-infected animals and the 50% effective dose (ED50) was calculated according to improved Karber’s method respectively. The levels of serum interleukin (IL)-1β, IL-6, Tumor Necrosis Factor alpha (TNF-α), Malondialdehyde (MDA), Glutathione Peroxidase (GSH-Px) and Hydroxyl Radical (·OH) were measured using dedicated assay kits. The statistical analysis of inflammatory factors and oxidative stress factors was tested using one-way ANOVA computed by SPSS software. The ED50 values for the prevention and treatment of MRSA infection in A. tasao-ko essential oil were 0.15 g/kg and 0.18 g/kg, respectively. A. tasao-ko essential oil significantly reduced the inflammatory factors (IL-1β, IL-6, TNF-α), oxidative stress factors (MDA, ·OH) and increased the GSH-Px content in mice infected with MRSA. In the high-dose group, 7 days after treatment, the cytokine contents have no difference with control group (P > 0.05). A. tasao-ko essential oil exhibited anti-MRSA effect in vivo and can also ameliorate the abnormal changes in inflammatory factors and oxidative stress that arise from MRSA.


2022 ◽  
Vol 12 ◽  
Author(s):  
Lei Mu ◽  
Limin Jiang ◽  
Juan Chen ◽  
Mei Xiao ◽  
Wei Wang ◽  
...  

Objective: To study the correlation between serum inflammatory factors, oxidative stress factors and frailty, and cognitive frailty in patients with cerebral small vessel disease (CSVD).Methods: A total of 281 patients with CSVD were selected from Tianjin Huanhu Hospital and Inner Mongolia People's Hospital from March 2019 to March 2021. CSVD was diagnosed by MRI. The FRAIL scale was used to evaluate the frailty of patients. Patients with CSVD with frailty and MMSE score <27 were considered to have cognitive frailty. Patients with non-cognitive frailty were included in the control group. The Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE) were used to evaluate the cognitive function of patients with CSVD. The serum interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-α), matrix metalloproteinase 3 (MMP-3), superoxide dismutase (SOD), and malondialdehyde (MDA) of patients with CSVD were detected. The correlation between blood inflammatory factors and oxidative stress factors with the frailty and cognitive frailty patients of CSVD were analyzed. Univariate and multivariate logistic regression were used to analyze the correlation between cognitive frailty and CSVD.Results: Among the patients with CSVD selected in this study, female patients and older patients had a higher proportion of frailty (p < 0.001). In the Frail group, MoCA score and MMSE score were significantly lower than in the Pre-Frail and Robust groups, Hamilton Depression Scale (HAMD) and Hamilton Anxiety Scale (HAMA) scores were significantly higher than the Pre-Frail and Robust groups, and the differences were statistically significant (p < 0.05). Serum CRP, IL-6, TNF-α, MMP-3, and MDA levels in the Frail group were higher, but SOD levels were lower. The levels of serum CRP, IL-6, TNF-α, MMP-3, and MDA in patients with CSVD in the Cognitive Frailty group were significantly higher than those of the Control group, while the levels of SOD were significantly lower than those of the Control group, and the differences were significant (p < 0.001). The results of univariate and multivariate logistic regression analysis showed that CRP, TNF-α, MMP-3, and MDA levels were associated with cognitive frailty in patients with CSVD (p < 0.05).Conclusion: The increase of serum CRP, TNF-α, MMP-3, and MDA levels are significantly related to the increased risk of frailty and cognitive frailty in patients with CSVD.


2020 ◽  
Vol 25 (40) ◽  
pp. 4310-4317 ◽  
Author(s):  
Lichao Sun ◽  
Shouqin Ji ◽  
Jihong Xing

Background/Aims: Central pro-inflammatory cytokine (PIC) signal is involved in neurological deficits after transient global ischemia induced by cardiac arrest (CA). The present study was to examine the role of microRNA- 155 (miR-155) in regulating IL-1β, IL-6 and TNF-α in the hippocampus of rats with induction of CA. We further examined the levels of products of oxidative stress 8-isoprostaglandin F2α (8-iso PGF2α, indication of oxidative stress); and 8-hydroxy-2’-deoxyguanosine (8-OHdG, indication of protein oxidation) after cerebral inhibition of miR-155. Methods: CA was induced by asphyxia and followed by cardiopulmonary resuscitation in rats. ELISA and western blot analysis were used to determine the levels of PICs and products of oxidative stress; and the protein expression of NADPH oxidase (NOXs) in the hippocampus. In addition, neurological severity score and brain edema were examined to assess neurological functions. Results: We observed amplification of IL-1β, IL-6 and TNF-α along with 8-iso PGF2α and 8-OHdG in the hippocampus of CA rats. Cerebral administration of miR-155 inhibitor diminished upregulation of PICs in the hippocampus. This also attenuated products of oxidative stress and upregulation of NOX4. Notably, inhibition of miR-155 improved neurological severity score and brain edema and this was linked to signal pathways of PIC and oxidative stress. Conclusion: We showed the significant role of blocking miR-155 signal in improving the neurological function in CA rats likely via inhibition of signal pathways of neuroinflammation and oxidative stress, suggesting that miR-155 may be a target in preventing and/or alleviating development of the impaired neurological functions during CA-evoked global cerebral ischemia.


Author(s):  
Hong Wang ◽  
Wenjuan Zhang ◽  
Jinren Liu ◽  
Junhong Gao ◽  
Le Fang ◽  
...  

Abstract Blast lung injury (BLI) is the major cause of death in explosion-derived shock waves; however, the mechanisms of BLI are not well understood. To identify the time-dependent manner of BLI, a model of lung injury of rats induced by shock waves was established by a fuel air explosive. The model was evaluated by hematoxylin and eosin staining and pathological score. The inflammation and oxidative stress of lung injury were also investigated. The pathological scores of rats’ lung injury at 2 h, 24 h, 3 days, and 7 days post-blast were 9.75±2.96, 13.00±1.85, 8.50±1.51, and 4.00±1.41, respectively, which were significantly increased compared with those in the control group (1.13±0.64; P<0.05). The respiratory frequency and pause were increased significantly, while minute expiratory volume, inspiratory time, and inspiratory peak flow rate were decreased in a time-dependent manner at 2 and 24 h post-blast compared with those in the control group. In addition, the expressions of inflammatory factors such as interleukin (IL)-6, IL-8, FosB, and NF-κB were increased significantly at 2 h and peaked at 24 h, which gradually decreased after 3 days and returned to normal in 2 weeks. The levels of total antioxidant capacity, total superoxide dismutase, and glutathione peroxidase were significantly decreased 24 h after the shock wave blast. Conversely, the malondialdehyde level reached the peak at 24 h. These results indicated that inflammatory and oxidative stress induced by shock waves changed significantly in a time-dependent manner, which may be the important factors and novel therapeutic targets for the treatment of BLI.


Pharmacology ◽  
2021 ◽  
pp. 1-11
Author(s):  
Naseratun Nessa ◽  
Miyuki Kobara ◽  
Hiroe Toba ◽  
Tetsuya Adachi ◽  
Toshiro Yamamoto ◽  
...  

Introduction: Periodontitis is a lifestyle-related disease that is characterized by chronic inflammation in gingival tissue. Febuxostat, a xanthine oxidase inhibitor, exerts anti-inflammatory and antioxidant effects. Objective: The present study investigated the effects of febuxostat on periodontitis in a rat model. Methods: Male Wistar rats were divided into 3 groups: control, periodontitis, and febuxostat-treated periodontitis groups. Periodontitis was induced by placing a ligature wire around the 2nd maxillary molar and the administration of febuxostat (5 mg/kg/day) was then initiated. After 4 weeks, alveolar bone loss was assessed by micro-computed tomography and methylene blue staining. The expression of osteoprotegerin (OPG), a bone resorption inhibitor, was detected by quantitative RT-PCR and immunological staining, and the number of osteoclasts in gingival tissue was assessed by tartrate-resistant acid phosphatase staining. The mRNA and protein expression levels of the proinflammatory cytokines, tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1β), in gingival tissue were measured using quantitative RT-PCR and immunological staining. Oxidative stress in gingival tissue was evaluated by the expression of 4-hydroxy-2-nonenal (4-HNE), and 8-hydroxy-2-deoxyguanosine (8-OHdG). To clarify the systemic effects of periodontitis, blood pressure and glucose tolerance were examined. Results: In rats with periodontitis, alveolar bone resorption was associated with reductions in OPG and increases in osteoclast numbers. The gingival expression of TNF-α, IL-1β, 4-HNE, and 8-OHdG was up-regulated in rats with periodontitis. Febuxostat significantly reduced alveolar bone loss, proinflammatory cytokine levels, and oxidative stress. It also attenuated periodontitis-induced glucose intolerance and blood pressure elevations. Conclusion: Febuxostat prevented the progression of periodontitis and associated systemic effects by inhibiting proinflammatory mediators and oxidative stress.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Noha H. Habashy ◽  
Ahmad S. Kodous ◽  
Marwa M. Abu-Serie

AbstractCarbon tetrachloride (CCl4) is an abundant environmental pollutant that can generate free radicals and induce oxidative stress in different human and animal organs like the kidney, lung, brain, and spleen, causing toxicity. The present study evaluated the alleviative mechanism of the isolated polyphenolic fraction from seedless (pulp and skin) black Vitis vinifera (VVPF) on systemic oxidative and necroinflammatory stress in CCl4-intoxicated rats. Here, we found that the administration of VVPF to CCl4-intoxicated rats for ten days was obviously ameliorated the CCl4-induced systemic elevation in ROS, NO and TBARS levels, as well as MPO activity. Also, it upregulated the cellular activities of the enzymatic (SOD, and GPx) and non-enzymatic (TAC and GSH) antioxidants. Furthermore, the gene expression of the ROS-related necroinflammatory mediators (NF-κB, iNOS, COX-2, and TNF-α) in the kidney, brain, and spleen, as well as IL-1β, and IL-8 in the lung were greatly restored. The histopathological studies confirmed these biochemical results and showed a noticeable enhancing effect in the architecture of the studied organs after VVPF intake. Thus, this study indicated that VVPF had an alleviative effect on CCl4-induced necroinflammation and oxidative stress in rat kidney, lung, brain, and spleen via controlling the ROS/NF-κB pathway.


2021 ◽  
Vol 12 ◽  
Author(s):  
Wenkai Yang ◽  
Hanjian Tu ◽  
Kai Tang ◽  
Haozhong Huang ◽  
Shi Ou ◽  
...  

This study investigated the effects of reynoutrin on the improvement of ischemic heart failure (IHF) and its possible mechanism in rats. The rat heart failure model was established by permanently ligating the left anterior descending coronary artery (LAD) and administering different doses of reynoutrin. Cardiac function, inflammatory factors releasing, oxidative stress, cardiomyocytes apoptosis, and myocardial fibrosis were evaluated. Western blotting was used to determine protein expression levels of S100 calcium-binding protein A1 (S100A1), matrix metallopeptidase 2(MMP2), MMP9, phosphorylated (p-) p65, and transforming growth factor -β1 (TGF-β1) in myocardial tissue of the left ventricle. Results showed that reynoutrin significantly improved cardiac function, suppressed the release of inflammatory factors, reduced oxidative stress, inhibited cardiomyocytes apoptosis, and attenuated myocardial fibrosis in rats with IHF. In rat myocardial tissue, permanent LAD-ligation resulted in a significant down-regulation in S100A1 expression, whereas reynoutrin significantly up-regulated S100A1 protein expression while down-regulating MMP2, MMP9, p-p65, and TGF-β1 expressions. However, when S100A1 was knocked down in myocardial tissue, the above-mentioned positive effects of reynoutrin were significantly reversed. Reynoutrin is a potential natural drug for the treatment of IHF, and its mechanism of action involves the up-regulation of S100A1 expression, thereby inhibiting expressions of MMPs and the transcriptional activity of nuclear factor kappa-B.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Jinfang Deng ◽  
Zhenpeng He ◽  
Xiuru Li ◽  
Wei Chen ◽  
Ziwen Yu ◽  
...  

Background. Huangkui capsule (HKC) comprises the total flavonoid extract of flowers of Abelmoschus manihot (L.) Medicus. This study aimed to explore the effects of HKC on lipopolysaccharide- (LPS-) induced acute lung injury (ALI) in mice and LPS-stimulated RAW 264.7 cells. Methods. Enzyme-linked immunosorbent assay, histopathology, spectrophotometry, and quantitative real-time polymerase chain reaction were used for the assessments. Statistical analysis was performed using a one-way analysis of variance. Results. LPS significantly increased lung inflammation, neutrophil infiltration, and oxidative stress and downregulated lung miR-451 expression. Treatment with HKC dramatically attenuated the lung wet/dry weight ratio, reduced the total cell count in the bronchoalveolar lavage fluid (BALF), and inhibited myeloperoxidase activity in the lung tissues 24 h after LPS challenge. Histopathological analysis demonstrated that HKC attenuated LPS-induced tissue oedema and neutrophil infiltration in the lung tissues. Additionally, the concentrations of tumour necrosis factor- (TNF-) α and interleukin- (IL-) 6 in BALF and IL-6 in the plasma reduced after HKC administration. Moreover, HKC could enhance glutathione peroxidase and catalase activities and upregulate the expression of miR-451 in the lung tissues. In vitro experiments revealed that HKC inhibited the production of nitric oxide, TNF-α, and IL-6 in LPS-induced RAW 264.7 cells and mouse primary peritoneal macrophages. Additionally, HKC downregulated LPS-induced transcription of TNF-α and IL-6 in RAW 264.7 cells. Conclusions. These findings suggest that HKC has anti-inflammatory and antioxidative effects that may protect mice against LPS-induced ALI and macrophage activation.


2016 ◽  
Vol 38 (6) ◽  
pp. 2163-2172 ◽  
Author(s):  
Xiaorong Hu ◽  
Ruisong Ma ◽  
Jiajia Lu ◽  
Kai Zhang ◽  
Weipan Xu ◽  
...  

Background/Aims: Inflammation and oxidative stress play an important role in myocardial ischemia and reperfusion (I/R) injury. We hypothesized that IL-23, a pro-inflammatory cytokine, could promote myocardial I/R injury by increasing the inflammatory response and oxidative stress. Methods: Male Sprague-Dawley rats were randomly assigned into sham operated control (SO) group, ischemia and reperfusion (I/R) group, (IL-23 + I/R) group and (anti-IL-23 + I/R) group. At 4 h after reperfusion, the serum concentration of lactate dehydrogenase (LDH), creatine kinase (CK) and the tissue MDA concentration and SOD activity were measured. The infarcte size was measured by TTC staining. Apoptosis in heart sections were measured by TUNEL staining. The expression of HMGB1 and IL-17A were detected by Western Blotting and the expression of TNF-α and IL-6 were detected by Elisa. Results: After 4 h reperfusion, compared with the I/R group, IL-23 significantly increased the infarct size, the apoptosis of cardiomyocytes and the levels of LDH and CK (all P < 0.05). Meanwhile, IL-23 significantly increased the expression of eIL-17A, TNF-α and IL-6 and enhanced both the increase of the MDA level and the decrease of the SOD level induced by I/R (all P<0.05). IL-23 had no effect on the expression of HMGB1 (p > 0.05). All these effects were abolished by anti-IL-23 administration. Conclusion: The present study suggested that IL-23 may promote myocardial I/R injury by increasing the inflammatory responses and oxidative stress reaction.


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