scholarly journals Ginsenoside Rg1 Ameliorates Neuroinflammation via Suppression of Connexin43 Ubiquitination to Attenuate Depression

2021 ◽  
Vol 12 ◽  
Author(s):  
Huiqin Wang ◽  
Yantao Yang ◽  
Songwei Yang ◽  
Siyu Ren ◽  
Juling Feng ◽  
...  

Depression is an inflammation-associated disease that results in major depression as inflammation increases and progresses. Ginsenoside Rg1 (Rg1), the major bioactive ingredient derived from ginseng, possesses remarkable anti-depressant and anti-inflammatory effects. Our previous studies showed that the pathogenesis of depression was concomitant with the acceleration of connexin43 (Cx43) ubiquitin degradation, while Rg1 could upregulate Cx43 expression to attenuate depression. However, whether the ubiquitination of Cx43 is the specific correlation between depression and inflammation, and how Rg1 ameliorates neuroinflammation to attenuate depression, are still under investigation. In in vivo experiments, Rg1 treatment significantly ameliorated depression-like behaviors in rats subjected to chronic unpredictable stress (CUS). Moreover, these CUS rats treated with Rg1 exhibited attenuated neuroinflammation, together with the suppression of Cx43 ubiquitination. In in vitro experiments, Rg1 reduced the secretion of inflammatory cytokines and the ubiquitination of Cx43 in lipopolysaccharide-induced glial cells. Furthermore, treatment with ubiquitin-proteasome inhibitor MG132 suppressing the ubiquitination of Cx43 ameliorated lipopolysaccharide-induced neuroinflammation. The results suggest that Rg1 attenuates depression-like behavioral performances in CUS-exposed rats; and the main mechanism of the antidepressant-like effects of Rg1 appears to involve protection against neuroinflammation via suppression of Cx43 ubiquitination. In conclusion, Rg1 could ameliorate neuroinflammation via suppression of Cx43 ubiquitination to attenuate depression, which represents the perspective of an innovative therapy of Rg1 in the treatment of inflammation-associated depression.

Biomolecules ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 110
Author(s):  
Dina Aweida ◽  
Shenhav Cohen

Protein degradation maintains cellular integrity by regulating virtually all biological processes, whereas impaired proteolysis perturbs protein quality control, and often leads to human disease. Two major proteolytic systems are responsible for protein breakdown in all cells: autophagy, which facilitates the loss of organelles, protein aggregates, and cell surface proteins; and the ubiquitin-proteasome system (UPS), which promotes degradation of mainly soluble proteins. Recent findings indicate that more complex protein structures, such as filamentous assemblies, which are not accessible to the catalytic core of the proteasome in vitro, can be efficiently degraded by this proteolytic machinery in systemic catabolic states in vivo. Mechanisms that loosen the filamentous structure seem to be activated first, hence increasing the accessibility of protein constituents to the UPS. In this review, we will discuss the mechanisms underlying the disassembly and loss of the intricate insoluble filamentous myofibrils, which are responsible for muscle contraction, and whose degradation by the UPS causes weakness and disability in aging and disease. Several lines of evidence indicate that myofibril breakdown occurs in a strictly ordered and controlled manner, and the function of AAA-ATPases is crucial for their disassembly and loss.


2021 ◽  
Vol 12 (5) ◽  
Author(s):  
Xuxing Shen ◽  
Chao Wu ◽  
Meng Lei ◽  
Qing Yan ◽  
Haoyang Zhang ◽  
...  

AbstractCarfilzomib, a second-generation proteasome inhibitor, has significantly improved the survival rate of multiple myeloma (MM) patients, but its clinical application is still restricted by drug resistance and cardiotoxicity. Here, we identified a novel proteasome inhibitor, D395, and assessed its efficacy in treating MM as well as its cardiotoxicity at the preclinical level. The activities of purified and intracellular proteasomes were measured to determine the effect of D395 on the proteasome. CCK-8 and flow cytometry experiments were designed to evaluate the effects of D395 on cell growth and apoptosis. The effects of D395 and carfilzomib on serum enzyme activity, echocardiography features, cardiomyocyte morphology, and hERG channels were also compared. In our study, D395 was highly cytotoxic to MM cell lines and primary MM cells but not normal cells, and it was well tolerated in vivo. Similar to carfilzomib, D395 inhibited osteoclast differentiation in a dose-dependent manner. In particular, D395 exhibited lower cardiotoxicity than carfilzomib in all experiments. In conclusion, D395 is a novel irreversible proteasome inhibitor that has remarkable anti-MM activity and mild cardiotoxicity in vitro and in vivo.


2010 ◽  
Vol 16 (14) ◽  
pp. 3648-3658 ◽  
Author(s):  
Enrica Marchi ◽  
Luca Paoluzzi ◽  
Luigi Scotto ◽  
Venkatraman E. Seshan ◽  
Jasmine M. Zain ◽  
...  

2018 ◽  
Vol 98 ◽  
pp. 58-68 ◽  
Author(s):  
Chenqing Ning ◽  
Xiaoguang Gao ◽  
Changyuan Wang ◽  
Yulong Kong ◽  
Zhihao Liu ◽  
...  

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Guo Zu ◽  
Jing Guo ◽  
Ningwei Che ◽  
Tingting Zhou ◽  
Xiangwen Zhang

Abstract Ginsenoside Rg1 (Rg1) is one of the major bioactive ingredients in Panax ginseng, and it attenuates inflammation and apoptosis. The aims of our study were to explore the potential of Rg1 for the treatment of intestinal I/R injury and to determine whether the protective effects of Rg1 were exerted through the Wnt/β-catenin signaling pathway. In this study, Rg1 treatment ameliorated inflammatory factors, ROS and apoptosis that were induced by intestinal I/R injury. Cell viability was increased and cell apoptosis was decreased with Rg1 pretreatment following hypoxia/reoxygenation (H/R) in the in vitro study. Rg1 activated the Wnt/β-catenin signaling pathway in both the in vivo and in vitro models, and in the in vitro study, the activation was blocked by DKK1. Our study provides evidence that pretreatment with Rg1 significantly reduces ROS and apoptosis induced by intestinal I/R injury via activation of the Wnt/β-catenin pathway. Taken together, our results suggest that Rg1 could exert its therapeutic effects on intestinal I/R injury through the Wnt/β-catenin signaling pathway and provide a novel treatment modality for intestinal I/R injury.


2016 ◽  
Vol 12 (2) ◽  
pp. 564-565
Author(s):  
Junping Zhang ◽  
Zheng Wei ◽  
Aihua Zhang ◽  
Junming Fan

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Andrew Morin ◽  
Caroline Soane ◽  
Angela Pierce ◽  
Bridget Sanford ◽  
Kenneth L Jones ◽  
...  

Abstract Background Atypical teratoid/thabdoid tumor (AT/RT) remains a difficult-to-treat tumor with a 5-year overall survival rate of 15%–45%. Proteasome inhibition has recently been opened as an avenue for cancer treatment with the FDA approval of bortezomib (BTZ) in 2003 and carfilzomib (CFZ) in 2012. The aim of this study was to identify and characterize a pre-approved targeted therapy with potential for clinical trials in AT/RT. Methods We performed a drug screen using a panel of 134 FDA-approved drugs in 3 AT/RT cell lines. Follow-on in vitro studies used 6 cell lines and patient-derived short-term cultures to characterize selected drug interactions with AT/RT. In vivo efficacy was evaluated using patient derived xenografts in an intracranial murine model. Results BTZ and CFZ are highly effective in vitro, producing some of the strongest growth-inhibition responses of the evaluated 134-drug panel. Marizomib (MRZ), a proteasome inhibitor known to pass the blood–brain barrier (BBB), also strongly inhibits AT/RT proteasomes and generates rapid cell death at clinically achievable doses in established cell lines and freshly patient-derived tumor lines. MRZ also significantly extends survival in an intracranial mouse model of AT/RT. Conclusions MRZ is a newer proteasome inhibitor that has been shown to cross the BBB and is already in phase II clinical trials for adult high-grade glioma (NCT NCT02330562 and NCT02903069). MRZ strongly inhibits AT/RT cell growth both in vitro and in vivo via a moderately well-characterized mechanism and has direct translational potential for patients with AT/RT.


2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Tao Wang ◽  
Yanbin Gao ◽  
Rongchuan Yue ◽  
Xiaolei Wang ◽  
Yimin Shi ◽  
...  

Background. Podocyte injury plays an important role in diabetic nephropathy (DN). The aim of this study was to determine the potential therapeutic effects of the ginsenoside Rg1 on hyperlipidemia-stressed podocytes and elucidate the underlying mechanisms. Methods. In vitro and in vivo models of DN were established as previously described, and the expression levels of relevant markers were analyzed by Western blotting, real-time Polymerase Chain Reaction (PCR), immunofluorescence, and immunohistochemistry. Results. Ginsenoside Rg1 alleviated pyroptosis in podocytes cultured under hyperlipidemic conditions, as well as in the renal tissues of diabetic rats, and downregulated the mammalian target of rapamycin (mTOR)/NF-κB pathway. In addition, Rg1 also inhibited hyperlipidemia-induced NLRP3 inflammasome in the podocytes, which was abrogated by the mTOR activator L-leucine (LEU). The antipyroptotic effects of Rg1 manifested as improved renal function in the DN rats. Conclusion. Ginsenoside Rg1 protects podocytes from hyperlipidemia-induced damage by inhibiting pyroptosis through the mTOR/NF-κB/NLRP3 axis, indicating a potential therapeutic function in DN.


2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Hailong Yu ◽  
Xiang Cao ◽  
Wei Li ◽  
Pinyi Liu ◽  
Yuanyuan Zhao ◽  
...  

Abstract Background In the central nervous system (CNS), connexin 43 (Cx43) is mainly expressed in astrocytes and regulates astrocytic network homeostasis. Similar to Cx43 overexpression, abnormal excessive opening of Cx43 hemichannels (Cx43Hcs) on reactive astrocytes aggravates the inflammatory response and cell death in CNS pathologies. However, the role of excessive Cx43Hc opening in intracerebral hemorrhage (ICH) injury is not clear. Methods Hemin stimulation in primary cells and collagenase IV injection in C57BL/6J (B6) mice were used as ICH models in vitro and in vivo. After ICH injury, the Cx43 mimetic peptide Gap19 was used for treatment. Ethidium bromide (EtBr) uptake assays were used to measure the opening of Cx43Hcs. Western blotting and immunofluorescence were used to measure protein expression. qRT-PCR and ELISA were used to determine the levels of cytokines. Coimmunoprecipitation (Co-IP) and the Duolink in situ proximity ligation assay (PLA) were applied to measure the association between proteins. Results In this study, Cx43 expression upregulation and excessive Cx43Hc opening was observed in mice after ICH injury. Delayed treatment with Gap19 significantly alleviated hematoma volume and neurological deficits after ICH injury. In addition, Gap19 decreased inflammatory cytokine levels in the tissue surrounding the hematoma and decreased reactive astrogliosis after ICH injury in vitro and in vivo. Intriguingly, Cx43 transcriptional activity and expression in astrocytes were significantly increased after hemin stimulation in culture. However, Gap19 treatment downregulated astrocytic Cx43 expression through the ubiquitin-proteasome pathway without affecting Cx43 transcription. Additionally, our data showed that Gap19 increased Yes-associated protein (YAP) nuclear translocation. This subsequently upregulated SOCS1 and SOCS3 expression and then inhibited the TLR4-NFκB and JAK2-STAT3 pathways in hemin-stimulated astrocytes. Finally, the YAP inhibitor, verteporfin (VP), reversed the anti-inflammatory effect of Gap19 in vitro and almost completely blocked its protective effects in vivo after ICH injury. Conclusions This study provides new insight into potential treatment strategies for ICH injury involving astroglial Cx43 and Cx43Hcs. Suppression of abnormal astroglial Cx43 expression and Cx43Hc opening by Gap19 has anti-inflammatory and neuroprotective effects after ICH injury.


Sign in / Sign up

Export Citation Format

Share Document