scholarly journals Intracerebral Injection of Heme Induces Lipid Peroxidation, Neuroinflammation, and Sensorimotor Deficits

Stroke ◽  
2021 ◽  
Author(s):  
Luiz Ricardo C. Vasconcellos ◽  
Letícia Martimiano ◽  
Danillo Pereira Dantas ◽  
Filipe Mota Fonseca ◽  
Hilton Mata-Santos ◽  
...  

Background and Purpose: Heme is a red blood cell component released in the brain parenchyma following intracerebral hemorrhage. However, the study of the pathophysiological mechanisms triggered by heme in the brain is hampered by the lack of well-established in vivo models of intracerebral heme injection. This study aims to optimize and characterize a protocol of intrastriatal heme injection in mice, with a focus on the induction of lipid peroxidation, neuroinflammation and, ultimately, sensorimotor deficits. We also evaluated the involvement of NLRP3 (NOD-, LRR-, and pyrin domain-containing protein 3), an inflammasome sensor, in the behavior deficits induced by heme in this model. Methods: Mice were injected with heme in the striatum for the evaluation of neuroinflammation and brain damage through histological and biochemical techniques. Immunoblot was used to evaluate the expression of proteins involved in heme/iron metabolism and antioxidant responses and the activation of the MAPK (mitogen-activated protein kinase) signaling pathway. For the assessment of neurological function, we followed-up heme-injected mice for 2 weeks using the rotarod, elevated body swing, and cylinder tests. Mice injected with the vehicle (sham), or autologous blood were used as controls. Results: Heme induced lipid peroxidation and inflammation in the brain. Moreover, heme increased the expression of HO-1 (heme oxygenase-1), ferritin, p62, and superoxide dismutase 2, and activated the MAPK signaling pathway promoting pro-IL (interleukin)-1β production and its cleavage to the active form. Heme-injected mice exhibited signs of brain damage and reactive astrogliosis around the injection site. Behavior deficits were observed after heme or autologous blood injection in comparison to sham-operated controls. In addition, behavior deficits and IL-1β production were reduced in Nlrp3 knockout mice in comparison to wild-type mice. Conclusions: Our results show that intracerebral heme injection induces neuroinflammation, and neurological deficits, in an NLRP3-dependent manner, suggesting that this is a feasible model to evaluate the role of heme in neurological disorders.

Author(s):  
Mariko Nakata ◽  
Masayuki Shimoda ◽  
Shinya Yamamoto

Abstract Irradiation with ultraviolet (UV) light on the cortical surface can induce a focal brain lesion (UV lesion) in rodents. In the present study, we investigated the process of establishing a UV lesion. Rats underwent UV irradiation (365 nm wavelength, 2.0 mWh) over the dura, and time-dependent changes in the cortical tissue were analyzed histologically. We found that the majority of neurons in the lesion started to degenerate within 24 hours and the rest disappeared within 5 days after irradiation. UV-induced neuronal degeneration progressed in a layer-dependent manner. Moreover, UV-induced terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) positivity and heme oxygenase-1 (HO-1) immunoreactivity were also detected. These findings suggest that UV irradiation in the brain can induce gradual neural degeneration and oxidative stress. Importantly, UV vulnerability may vary among cortical layers. UV-induced cell death may be due to apoptosis; however, there remains a possibility that UV-irradiated cells were degenerated via processes other than apoptosis. The UV lesion technique will not only assist in investigating brain function at a targeted site but may also serve as a pathophysiological model of focal brain injury and/or neurodegenerative disorders.


Author(s):  
Ayano Tsuru ◽  
Yumi Hamazaki ◽  
Shuta Tomida ◽  
Mohammad Shaokat Ali ◽  
Eriko Kage-Nakadai

Abstract Cutibacterium acnes plays roles in both acne disease and healthy skin ecosystem. We observed that mutations in the tir-1/SARM1 and p38 MAPK cascade genes significantly shortened Caenorhabditis elegans lifespan upon Cutibacterium acnes SK137 infection. Antimicrobial molecules were induced by SK137 in a TIR-1-dependent manner. These results suggest that defense responses against SK137 involve the TIR-1-p38 MAPK pathway in Caenorhabditis elegans.


Processes ◽  
2020 ◽  
Vol 8 (7) ◽  
pp. 767
Author(s):  
Byoung Ha Kim ◽  
Won-Yung Lee ◽  
Tuy An Trinh ◽  
Jae Sung Pyo ◽  
Sooyeun Lee ◽  
...  

Janus kinase 3 (JAK3) inhibitors have been used effectively in the treatment of several cases of alopecia universalis and its variants. Our study aims to evaluate whether the emulsion extract of brevilin A from Centipeda minima (CMX) stimulates hair regrowth in a clinical trial, as a JAK3 inhibitor, combined with network pharmacology-based analysis. CMX showed potent inhibition of JAK3 in a concentration-dependent manner. Significant differences in total hair count, terminal hair count, and anagen hair count from the baseline to 24 weeks were observed between the placebo and CMX subjects. The gene set enrichment analysis showed that the targets of CMX are mainly associated with the JAK-STAT signaling pathway, cytokine–cytokine receptor interactions, and the MAPK signaling pathway. This study suggests that the medicinal herbal extract CMX is useful in the treatment of mild to moderate vertex balding that contribute to the visible improvements in hair growth observed in treated patients.


2015 ◽  
Vol 36 (4) ◽  
pp. 1539-1551 ◽  
Author(s):  
Qian Yu ◽  
Zhihong Lu ◽  
Lei Tao ◽  
Lu Yang ◽  
Yu Guo ◽  
...  

Background/Aims: Stroke is among the top causes of death worldwide. Neuroprotective agents are thus considered as potentially powerful treatment of stroke. Methods: Using both HT22 cells and male Sprague-Dawley rats as in vitro and in vivo models, we investigated the effect of NaHS, an exogenous donor of H2S, on the focal cerebral ischemia-reperfusion (I/R) induced brain injury. Results: Administration of NaHS significantly decreased the brain infarcted area as compared to the I/R group in a dose-dependent manner. Mechanistic studies demonstrated that NaHS-treated rats displayed significant reduction of malondialdehyde content, and strikingly increased activity of superoxide dismutases and glutathione peroxidase in the brain tissues compared with I/R group. The enhanced antioxidant capacity as well as restored mitochondrial function are NaHS-treatment correlated with decreased cellular reactive oxygen species level and compromised apoptosis in vitro or in vivo in the presence of NaHS compared with control. Further analysis revealed that the inhibition of PARP-1 cleavage and AIF translocation are involved in the neuroprotective effects of NaHS. Conclusion: Collectively, our results suggest that NaHS has potent protective effects against the brain injury induced by I/R. NaHS is possibly effective through inhibition of oxidative stress and apoptosis.


2018 ◽  
Vol 315 (3) ◽  
pp. F503-F511 ◽  
Author(s):  
Zhizhi Zhuang ◽  
Jia Xiao ◽  
Xinxin Chen ◽  
Xiaohan Hu ◽  
Ruidian Li ◽  
...  

G protein pathway suppressor 2 (GPS2) is a multifunctional protein and transcriptional regulation factor that is involved in the G protein MAPK signaling pathway. It has been shown that the MAPK signaling pathway plays an important role in the regulation of renal large-conductance Ca2+-activated potassium (BK) channels. In this study, we investigated the effects of GPS2 on BK channel activity and protein expression. In human embryonic kidney (HEK) BK stably expressing cells transfected with either GPS2 or its vector control, a single-cell recording showed that GPS2 significantly increased BK channel activity ( NPo), increasing BK open probability ( Po), and channel number ( N) compared with the control. In Cos-7 cells and HEK 293 T cells, GPS2 overexpression significantly enhanced the total protein expression of BK in a dose-dependent manner. Knockdown of GPS2 expression significantly decreased BK protein expression, while increasing ERK1/2 phosphorylation. Knockdown of ERK1/2 expression reversed the GPS2 siRNA-mediated inhibition of BK protein expression in Cos-7 cells. Pretreatments of Cos-7 cells with either the lysosomal inhibitor bafilomycin A1 or the proteasomal inhibitor MG132 partially reversed the inhibitory effects of GPS2 siRNA on BK protein expression. In addition, feeding a high-potassium diet significantly increased both GPS2 and BK protein abundance in mice. These data suggest that GPS2 enhances BK channel activity and its protein expression by reducing ERK1/2 signaling-mediated degradation of the channel.


2013 ◽  
Vol 81 (12) ◽  
pp. 4551-4560 ◽  
Author(s):  
Yoku Hayakawa ◽  
Yoshihiro Hirata ◽  
Hiroto Kinoshita ◽  
Kosuke Sakitani ◽  
Hayato Nakagawa ◽  
...  

ABSTRACTThe mitogen-activated protein kinase (MAPK) signaling pathway regulates various cellular functions, including those induced byHelicobacter pylori. TAK1 is an upstream MAPK kinase kinase (MAP3K) required forH. pylori-induced MAPK and NF-κB activation, but it remains unclear whether other MAP3Ks are involved inH. pylori-induced cellular responses. In this study, we focused on the MAP3K ASK1, which plays a critical role in gastric tumorigenesis. In gastric epithelial cells,H. pyloriactivates ASK1 in a reactive oxygen species (ROS)- andcagpathogenicity island-dependent manner, and ASK1 regulates sustained JNK activation and apoptosis induced byH. pylori. In contrast, TAK1 regulatesH. pylori-mediated early JNK activation and cytokine production. We also found reciprocal regulation between ASK1 and TAK1 inH. pylori-related responses, whereby inhibition of TAK1 or downstream p38 MAPK activates ASK1 through ROS production, and ASK1 suppresses TAK1 and downstream NF-κB activation. We identified ROS/ASK1/JNK as a new signaling pathway induced byH. pylori, which regulates apoptotic cell death. The balance of ASK1-induced apoptosis and TAK1-induced antiapoptotic or inflammatory responses may determine the fate of epithelial cells infected withH. pyloriand thus be involved in the pathogenesis of gastritis and gastric cancer.


2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Li-qian Zhang ◽  
Rong-wei Lv ◽  
Xiang-dong Qu ◽  
Xian-jun Chen ◽  
Hong-sheng Lu ◽  
...  

Aloesin is an active constituent of the herb aloe vera and plays a crucial role in anti-inflammatory activity, ultraviolet protection, and antibacterium. We investigated the role and possible mechanisms of aloesin in the cell growth and metastasis of ovarian cancer. It was found that aloesin inhibited cell viability and cell clonality in a dose-dependent manner. It arrests the cell cycle at the S-phase and induced apoptosis in SKOV3 cells. In an in vivo experiment, it was observed that aloesin inhibited tumor growth. Moreover, it inhibited migration and invasion of cancer in SKOV3 cells. Interestingly, members from the mitogen-activated protein kinase (MAPK) signaling family became less phosphorylated as the aloesin dose increased. This suggests that aloesin exerts its anticancer effect through the MAPK signaling pathway. Our data also highlights the possibility of using aloesin as a novel therapeutic drug for ovarian cancer treatment.


Function ◽  
2021 ◽  
Author(s):  
Zhong Peng ◽  
Stephan Kellenberger

Abstract Hydrogen sulfide (H2S) emerged recently as a new gasotransmitter and was shown to exert cellular effects by interacting with proteins, among them many ion channels. Acid-sensing ion channels (ASICs) are neuronal voltage-insensitive Na+ channels activated by extracellular protons. ASICs are involved in many physiological and pathological processes, such as fear conditioning, pain sensation and seizures. We characterize here the regulation of ASICs by H2S. In transfected mammalian cells, the H2S donor NaHS increased the acid-induced ASIC1a peak currents in a time- and concentration-dependent manner. Similarly, NaHS potentiated also the acid-induced currents of ASIC1b, ASIC2a and ASIC3. An upregulation induced by the H2S donors NaHS and GYY4137 was also observed with the endogenous ASIC currents of cultured hypothalamus neurons. In parallel with the effect on function, the total and plasma membrane expression of ASIC1a was increased by GYY4137, as determined in cultured cortical neurons. H2S also enhanced the phosphorylation of extracellular signal-regulated kinase, which belongs to the family of mitogen-activated protein kinases (MAPKs). Pharmacological blockade of the MAPK signaling pathway prevented the GYY4137-induced increase of ASIC function and expression, indicating that this pathway is required for ASIC regulation by H2S. Our study demonstrates that H2S regulates ASIC expression and function, and identifies the involved signaling mechanism. Since H2S shares several roles with ASICs, as e.g. facilitation of learning and memory, protection during seizure activity and modulation of nociception, it may be possible that H2S exerts some of these effects via a regulation of ASIC function.


BMC Medicine ◽  
2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Xiaoyu Xie ◽  
Huanran Lv ◽  
Chenxi Liu ◽  
Xiaonan Su ◽  
Zhen Yu ◽  
...  

Abstract Background We and others have confirmed activation of macrophages plays a critical role in liver injury and fibrogenesis during HBV infection. And we have also proved HBeAg can obviously induce the production of macrophage inflammatory cytokines compared with HBsAg and HBcAg. However, the receptor and functional domain of HBeAg in macrophage activation and its effects and mechanisms on hepatic fibrosis remain elusive. Methods The potentially direct binding receptors of HBeAg were screened and verified by Co-IP assay. Meanwhile, the function domain and accessible peptides of HBeAg for macrophage activation were analyzed by prediction of surface accessible peptide, construction, and synthesis of truncated fragments. Furthermore, effects and mechanisms of the activation of hepatic stellate cells induced by HBeAg-treated macrophages were investigated by Transwell, CCK-8, Gel contraction assay, Phospho Explorer antibody microarray, and Luminex assay. Finally, the effect of HBeAg in hepatic inflammation and fibrosis was evaluated in both human and murine tissues by immunohistochemistry, immunofluorescence, ELISA, and detection of liver enzymes. Results Herein, we verified TLR-2 was the direct binding receptor of HBeAg. Meanwhile, C-terminal peptide (122-143 aa.) of core domain in HBeAg was critical for macrophage activation. But arginine-rich domain of HBcAg hided this function, although HBcAg and HBeAg shared the same core domain. Furthermore, HBeAg promoted the proliferation, motility, and contraction of hepatic stellate cells (HSCs) in a macrophage-dependent manner, but not alone. PI3K-AKT-mTOR and p38 MAPK signaling pathway were responsible for motility phenotype of HSCs, while the Smad-dependent TGF-β signaling pathway for proliferation and contraction of them. Additionally, multiple chemokines and cytokines, such as CCL2, CCL5, CXCL10, and TNF-α, might be key mediators of HSC activation. Consistently, HBeAg induced transient inflammation response and promoted early fibrogenesis via TLR-2 in mice. Finally, clinical investigations suggested that the level of HBeAg is associated with inflammation and fibrosis degrees in patients infected with HBV. Conclusions HBeAg activated macrophages via the TLR-2/NF-κB signal pathway and further exacerbated hepatic fibrosis by facilitating motility, proliferation, and contraction of HSCs with the help of macrophages.


2019 ◽  
Vol 5 (suppl) ◽  
pp. 41-41
Author(s):  
ChunXia Su ◽  
Juan Zhou ◽  
Xiangling Chu ◽  
Jing Zhao

41 Background: Lung cancer is the most common cause of mortality in both men and women, accounting for one-quarter of all cancer deaths. Most lung cancer-associated deaths result from metastasis, especially brain metastasis. Metastasis associated mutations are important biomarkers for metastasis prediction and outcome improvement. The current study aimed to reveal the molecular mechanisms and the genetic alterations involved in metastasis from lung tumors to the brain. Methods: We carried out whole exome sequencing (WES) of the primary tumors and the corresponding brain metastases from 15 patients with metastatic non-small-cell lung carcinoma. Results: We identified novel lung cancer metastases associated genes (CHEK2P2, BAGE2, AHNAK2) and epigenetic factors (miR-4436A, miR-6077). Lung-brain metastasis samples have more similar Ti/Tv(transition/transversion) profile with brain cancer. Focal adhesion, PI3K-Akt signaling pathway, MAPK signaling pathway are some of the most important tumor onset and metastasis pathways. Alternative splicing, Methylation and EGF-like domain are important metabolic abnormal for the lung-metastasis cancers. Conclusions: We conducted a pairwise lung-brain metastasis based WES and identified some novel metastasis related mutations which provided potential biomarkers for prognosis and targeted therapeutics.


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