Proteasome activity in experimental diabetes

2006 ◽  
Vol 1 (2) ◽  
pp. 289-298 ◽  
Author(s):  
Albena Alexandrova ◽  
Lubomir Petrov ◽  
Margarita Kirkova
Keyword(s):  
Oxidative Stress ◽  
Lipid Peroxidation ◽  
Protein Oxidation ◽  
Experimental Diabetes ◽  
Diabetic Rats ◽  
Ubiquitin Proteasome Pathway ◽  
Ubiquitin Proteasome ◽  
Proteasome Pathway ◽  
And Oxidative Stress

AbstractNumerous studies have indicated that oxidative stress contributes to the development and progression of diabetes and other related complications. Since the ubiquitin-proteasome pathway is involved in degradation of oxidized proteins, it is to be expected that alterations in proteasome-dependent proteolysis accompany diabetes. This paper focuses on the role of the proteasome in alloxan-induced experimental diabetes. The changes in proteasomal activity and oxidative stress indices (protein oxidation and lipid peroxidation) were evaluated. The obtained results revealed increased protein oxidation and lipid peroxidation, as well as alterations in proteasomal activities in diabetic rats. Our data indicates a significant decrease in chymotryptic-like activity; increased tryptic-like activity; and unchanged post-glutamyl peptide hydrolytic-like activity. These findings suggest the presence of oxidative stress in diabetes that appears to result in changes to the ubiquitin-proteasome pathway.

Protective role of Sterculia tragacantha aqueous extract on pancreatic gene expression and oxidative stress parameters in streptozotocin-induced diabetic rats

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Basiru Olaitan Ajiboye ◽  
Babatunji Emmanuel Oyinloye ◽  
Jennifer Chidera Awurum ◽  
Sunday Amos Onikanni ◽  
Adedotun Adefolalu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Body Weight ◽  
Protective Role ◽  
Diabetic Rats ◽  
Gene Expressions ◽  
Ki 67 ◽  
Oxidative Stress Parameters ◽  
And Oxidative Stress ◽  
Stress Parameters

Abstract Objectives The current study evaluates the protective role of aqueous extract of Sterculia tragacantha leaf (AESTL) on pancreatic gene expressions (insulin, PCNA, PDX-1, KI-67 and GLP-1R) and oxidative stress parameters in streptozotocin-induced diabetic rats. Methods Diabetes mellitus was induced into the experimental Wistar animals via intraperitoneal (IP) injection of streptozotocin (35 mg/kg body weight) and 5% glucose water was given to the rats for 24 h after induction. The animals were categorized into five groups of 10 rats each as follows normal control, diabetic control, diabetic rats administered AESTL (150 and 300 mg/kg body weight) and diabetic rats administered metformin (200 mg/kg) orally for two weeks. Thereafter, the animals were euthanized, blood sample collected, pancreas harvested and some pancreatic gene expressions (such as insulin, PCNA, PDX-1, KI-67, and GLP-1R)s as well as oxidative stress parameters were analyzed. Results The results revealed that AESTL significantly (p<0.05) reduced fasting blood glucose level, food and water intake, and lipid peroxidation in diabetic rats. Diabetic rats administered different doses of AESTL showed a substantial upsurge in body weight, antioxidant enzyme activities, and pancreatic gene expressions (insulin, PCNA, PDX-1, KI-67, and GLP-1R). Conclusions It can therefore be concluded that AESTL has the ability to protect the pancreas during diabetes mellitus conditions.

Abstract 44: TAK1 Regulates Caspase 8 Activation and Necroptotic Signaling via Multiple Cell Death Checkpoints

2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Xaioyun Guo ◽  
Haifeng Yin ◽  
Yi Chen ◽  
Lei Li ◽  
Jing Li ◽  
...  
Keyword(s):  
Cell Death ◽  
Adaptor Protein ◽  
Regulatory Mechanisms ◽  
Caspase 8 ◽  
Ubiquitin Proteasome Pathway ◽  
Pathological Conditions ◽  
Ubiquitin Proteasome ◽  
Multiple Cell ◽  
Proteasome Pathway

Necroptosis has emerged as a new form of programmed cell death implicated in a number of pathological conditions such as ischemic injury, neurodegenerative disease, and viral infection. Recent studies indicate that TGFβ-activated kinase 1 (TAK1) is nodal regulator of necroptotic cell death, but the underlying molecular regulatory mechanisms remain elusive. Here we reported that TAK1 regulates necroptotic signaling as well as caspase 8 activation through both NFκB-dependent and -independent mechanisms. Inhibition of TAK1 promoted TNFα-induced necroptosis through the induction of RIP1 phosphorylation/activation and necrosome formation, in the presence of ongoing caspase activation. Further, inhibition of TAK1 triggered two caspase 8 activation pathways through the induction of RIP1-FADD-caspase 8 complex as well as FLIP cleavage/degradation. Mechanistically, our data uncovered an essential role of the adaptor protein TRADD in caspase 8 activation and necrosome formation triggered by TAK1 inhibition. Moreover, ablation of the deubiqutinase CYLD prevented both apoptotic and necroptotic signaling induced by TAK1 inhibition, whereas deletion of the E3 ubiquitin ligase TRAF2 had the opposite effect. Finally, blocking the ubiquitin-proteasome pathway prevented the degradation of key necroptotic signaling proteins and necrosome formation. Thus we identified novel regulatory mechanisms underling the critical role of TAK1 in necroptotic signaling through regulation of multiple cell death checkpoints. Targeting key components of the necroptotic pathway (e.g., TRADD and CYLD) and the ubiquitin-proteasome pathway may represent novel therapeutic strategies for pathological conditions driven by necroptosis.

Participation of the ubiquitin-proteasome pathway in rat oocyte activation

Zygote ◽  
2005 ◽  
Vol 13 (1) ◽  
pp. 87-95 ◽  
Author(s):  
Xin Tan ◽  
An Peng ◽  
Yong-Chao Wang ◽  
Yue Wang ◽  
Qing-Yuan Sun
Keyword(s):  
Meiotic Division ◽  
Polar Body ◽  
Meiotic Spindle ◽  
Oocyte Activation ◽  
Parthenogenetic Activation ◽  
Ubiquitin Proteasome Pathway ◽  
Ubiquitin Proteasome ◽  
Proteasome Pathway ◽  
Second Polar Body

The role of the ubiquitin-proteasome pathway (UPP) in mitosis is well known. However, its role in meiotic division is still poorly documented, especially in the activation of mammalian oocytes. In this study, the role of proteasome in the spontaneous and parthenogenetic activation of rat oocytes was investigated. We found that ALLN, an inhibitor of proteasome, when applied to metaphase II oocytes, inhibited spontaneous activation, blocked extrusion of the second polar body (PB) and caused the withdrawal of the partially extruded second PB. ALLN also inhibited the parthenogenetic activation induced by cycloheximide, but had no effect on the formation of pronuclei in activated eggs. In metaphase and anaphase, ubiquitin and proteasome localized to the meiotic spindle, concentrating on both sides of the oocyte–second PB boundary during PB extrusion. This pattern of cellular distribution suggests that UPP may have a role in regulating nuclear division and cytokinesis. Ubiquitin was seen to form a ring around the pronucleus, whereas proteasome was evenly distributed in the pronuclear region. Taken together, our results indicate that (1) UPP is required for the transitions of oocytes from metaphase II to anaphase II and from anaphase II to the end of meiosis; and (2) the UPP plays a role in cytokinesis of the second meiotic division.

Role of the ubiquitin-proteasome pathway and some peptidases during seed germination and copper stress in bean cotyledons

2014 ◽  
Vol 76 ◽  
pp. 77-85 ◽  
Author(s):  
Inès Karmous ◽  
Abdelilah Chaoui ◽  
Khadija Jaouani ◽  
David Sheehan ◽  
Ezzedine El Ferjani ◽  
...  
Keyword(s):  
Seed Germination ◽  
Copper Stress ◽  
Ubiquitin Proteasome Pathway ◽  
Ubiquitin Proteasome ◽  
Proteasome Pathway
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