scholarly journals Role of Salt-Induced Kinase 1 in Androgen Neuroprotection against Cerebral Ischemia

2010 ◽  
Vol 31 (1) ◽  
pp. 339-350 ◽  
Author(s):  
Jian Cheng ◽  
Masayoshi Uchida ◽  
Wenri Zhang ◽  
Marjorie R Grafe ◽  
Paco S Herson ◽  
...  

Androgens within physiological ranges protect castrated male mice from cerebral ischemic injury. Yet, underlying mechanisms are unclear. Here, we report that, after middle cerebral artery occlusion (MCAO), salt-induced kinase 1 (SIK1) was induced by a potent androgen—dihydrotestosterone (DHT) at protective doses. To investigate whether SIK1 contributes to DHT neuroprotection after cerebral ischemia, we constructed lentivirus-expressing small interference RNA (siRNA) against SIK1. The SIK1 knockdown by siRNA exacerbated oxygen–glucose deprivation (OGD)-induced cell death in primary cortical neurons, suggesting that SIK1 is an endogenous neuroprotective gene against cerebral ischemia. Furthermore, lentivirus-mediated SIK1 knockdown increased both cortical and striatal infarct sizes in castrated mice treated with a protective dose of DHT. Earlier studies show that SIK1 inhibits histone deacetylase (HDAC) activities by acting as a class IIa HDAC kinase. We observed that SIK1 knockdown decreased histone H3 acetylation in primary neurons. The SIK1 siRNA also exacerbated OGD-induced neuronal death in the presence of trichostatin A (TSA), an HDAC inhibitor, and decreased histone H3 acetylation at 4 hours reoxygenation in TSA-treated neurons. Finally, we showed that DHT at protective doses prevented ischemia-induced histone deacetylation after MCAO. Our finding suggests that SIK1 contributes to neuroprotection by androgens within physiological ranges by inhibiting histone deacetylation.

2020 ◽  
Vol 61 (9) ◽  
pp. 1646-1660
Author(s):  
Haidao Zhang ◽  
Fu Guo ◽  
Peipei Qi ◽  
Yizi Huang ◽  
Yongyao Xie ◽  
...  

Abstract Histone deacetylases (HDACs) play important roles in the regulation of eukaryotic gene expression. The role of HDACs in specialized transcriptional regulation and biological processes is poorly understood. In this study, we evaluated the global expression patterns of genes related to epigenetic modifications during callus initiation in rice. We found that the repression of HDAC activity by trichostatin A (TSA) or by OsHDA710 mutation (hda710) results in impaired callus formation of rice mature embryo and increased global histone H3 acetylation levels. The HDAC inhibition decreased auxin response and cell proliferation in callus formation. Meanwhile, the transcriptional repressors OsARF18 and OsARF22 were upregulated in the callus of hda710. The chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) analysis demonstrated that the callus of hda710 exhibited enhanced histone H3 acetylation levels at the chromatin regions of OsARF18 and OsARF22. Furthermore, we found that OsARF18 and OsARF22 were regulated through OsHDA710 recruitment to their target loci. In addition, overexpression of OsARF18 decreased the transcription of downstream genes PLT1 and PLT2 and inhibited callus formation of the mature embryo. These results demonstrate that OsHDA710 regulates callus formation by suppressing repressive OsARFs via histone deacetylation during callus formation of rice mature embryo. This indicates that OsHDA710-mediated histone deacetylation is an epigenetic regulation pathway for maintaining auxin response during cell dedifferentiation.


2020 ◽  
Vol 14 (8) ◽  
pp. 1103-1118
Author(s):  
Chunxiao Li ◽  
Yi Chen ◽  
Huatuo Zhu ◽  
Xiuming Zhang ◽  
Lu Han ◽  
...  

Abstract Background Ulcerative colitis [UC] is a common chronic inflammatory bowel disease without curative treatment. Methods We conducted gene set enrichment analysis to explore potential therapeutic agents for UC. Human colon tissue samples were collected to test H3 acetylation in UC. Both in vivo and in vitro colitis models were constructed to verify the role and mechanism of H3 acetylation modification in UC. Intestine-specific vitamin D receptor [VDR]-/- mice and VD [vitamin D]-deficient diet-fed mice were used to explore downstream molecular mechanisms accordingly. Results According to the Connectivity Map database, MS-275 [class I histone deacetylase inhibitor] was the top-ranked agent, indicating the potential importance of histone acetylation in the pathogenesis of UC. We then found that histone H3 acetylation was significantly lower in the colon epithelium of UC patients and negatively associated with disease severity. MS-275 treatment inhibited histone H3 deacetylation, subsequently attenuating nuclear factor kappa B [NF-κB]-induced inflammation, reducing cellular apoptosis, maintaining epithelial barrier function, and thereby reducing colitis activity in a mouse model of colitis. We also identified VDR as be a downstream effector of MS-275. The curative effect of MS-275 on colitis was abolished in VDR-/- mice and in VD-deficient diet-fed mice and VDR directly targeted p65. In UC patients, histone H3 acetylation, VDR and zonulin-1 expression showed similar downregulation patterns and were negatively associated with disease severity. Conclusions We demonstrate that MS-275 inhibits histone deacetylation and alleviates colitis by ameliorating inflammation, reducing apoptosis, and maintaining intestinal epithelial barrier via VDR, providing new strategies for UC treatment.


Human Cell ◽  
2021 ◽  
Author(s):  
Jiaying Zhu ◽  
Zhu Zhu ◽  
Yipin Ren ◽  
Yukang Dong ◽  
Yaqi Li ◽  
...  

AbstractLINGO-1 may be involved in the pathogenesis of cerebral ischemia. However, its biological function and underlying molecular mechanism in cerebral ischemia remain to be further defined. In our study, middle cerebral artery occlusion/reperfusion (MACO/R) mice model and HT22 cell oxygen–glucose deprivation/reperfusion (OGD/R) were established to simulate the pathological process of cerebral ischemia in vivo and in vitro and to detect the relevant mechanism. We found that LINGO-1 mRNA and protein were upregulated in mice and cell models. Down-regulation LINGO-1 improved the neurological symptoms and reduced pathological changes and the infarct size of the mice after MACO/R. In addition, LINGO-1 interference alleviated apoptosis and promoted cell proliferation in HT22 of OGD/R. Moreover, down-regulation of LINGO-1 proved to inhibit nuclear translocation of p-NF-κB and reduce the expression level of p-JAK2 and p-STAT3. In conclusion, our data suggest that shLINGO-1 attenuated ischemic injury by negatively regulating NF-KB and JAK2/STAT3 pathways, highlighting a novel therapeutic target for ischemic stroke.


2021 ◽  
pp. 1-8
Author(s):  
Hong Liu ◽  
Qiaomei Dai ◽  
Jing Yang ◽  
Yuwei Zhang ◽  
Bo Zhang ◽  
...  

<b><i>Introduction:</i></b> Cerebral ischemia and reperfusion (CI/R) injury is a devasting cerebrovascular disease, accompanied with ischemia stroke, cerebral infarction. Zuogui Pill (ZGP), as a Chinese traditional medicine, is proved to be effective in many diseases and cancers. Our study aimed to detect the roles of ZGP in CI/R injury. <b><i>Methods:</i></b> Neural stem cells were isolated from rats and induced by oxygen and glucose deprivation and recovery. CCK-8 and flow cytometry were applied to assess the function of ZGP on cell viability and apoptosis. Rat CI/R injury models were established by the middle cerebral artery occlusion and reperfusion. The function of ZGP on CI/R injury was identified via evaluating modified neurological severity score, infarct area, and cognitive impairment. <b><i>Results:</i></b> Compared to the control, the cell viability was obviously decreased in the oxygen and glucose deprivation and recovery (OGD/R) group, while the adverse influence on cells was reversed by cultured plus 10% ZGP serum. Consistently, ZGP attenuated the influence of OGD/R on cell apoptosis. More importantly, ZGP could alleviate CI/R injury of rats by reducing neurological damage and infarct area and promoting cognitive function. <b><i>Conclusion:</i></b> This study provided protective roles of ZGP on cell viability and apoptosis induced by OGD/R. In addition, ZGP played protective roles on neuroinflammation and cognitive function in rats.


2018 ◽  
Vol 19 (12) ◽  
pp. 4071 ◽  
Author(s):  
Mei-Chi Chang ◽  
Yunn-Jy Chen ◽  
Yun-Chia Lian ◽  
Bei-En Chang ◽  
Chih-Chia Huang ◽  
...  

Butyric acid as a histone deacetylase (HDAC) inhibitor is produced by a number of periodontal and root canal microorganisms (such as Porphyromonas, Fusobacterium, etc.). Butyric acid may affect the biological activities of periodontal/periapical cells such as osteoblasts, periodontal ligament cells, etc., and thus affect periodontal/periapical tissue destruction and healing. The purposes of this study were to study the toxic effects of butyrate on the matrix and mineralization marker expression in MG-63 osteoblasts. Cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Cellular apoptosis and necrosis were analyzed by propidium iodide/annexin V flow cytometry. The protein and mRNA expression of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-B ligand (RANKL) were analyzed by Western blotting and reverse transcriptase-polymerase chain reaction (RT-PCR). OPG, soluble RANKL (sRANKL), 8-isoprostane, pro-collagen I, matrix metalloproteinase-2 (MMP-2), osteonectin (SPARC), osteocalcin and osteopontin (OPN) secretion into culture medium were measured by enzyme-linked immunosorbant assay. Alkaline phosphatase (ALP) activity was checked by ALP staining. Histone H3 acetylation levels were evaluated by immunofluorescent staining (IF) and Western blot. We found that butyrate activated the histone H3 acetylation of MG-63 cells. Exposure of MG-63 cells to butyrate partly decreased cell viability with no marked increase in apoptosis and necrosis. Twenty-four hours of exposure to butyrate stimulated RANKL protein expression, whereas it inhibited OPG protein expression. Butyrate also inhibited the secretion of OPG in MG-63 cells, whereas the sRANKL level was below the detection limit. However, 3 days of exposure to butyrate (1 to 8 mM) or other HDAC inhibitors such as phenylbutyrate, valproic acid and trichostatin stimulated OPG secretion. Butyrate stimulated 8-isoprostane, MMP-2 and OPN secretion, but not procollagen I, or osteocalcin in MG-63 cells. Exposure to butyrate (2–4 mM) for 3 days markedly stimulated osteonectin secretion and ALP activity. In conclusion, higher concentrations of butyric acid generated by periodontal and root canal microorganisms may potentially induce bone destruction and impair bone repair by the alteration of OPG/RANKL expression/secretion, 8-isoprostane, MMP-2 and OPN secretion, and affect cell viability. However, lower concentrations of butyrate (1–4 mM) may stimulate ALP, osteonectin and OPG. These effects are possibly related to increased histone acetylation. These events are important in the pathogenesis and repair of periodontal and periapical destruction.


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