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Pharmaceuticals (Basel, Switzerland) Jun 2024Parkinson's disease (PD) is a prevalent neurodegenerative disorder among the elderly population. The pathogenesis of PD encompasses genetic alterations, environmental... (Review)
Review
Parkinson's disease (PD) is a prevalent neurodegenerative disorder among the elderly population. The pathogenesis of PD encompasses genetic alterations, environmental factors, and age-related neurodegenerative processes. Numerous studies have demonstrated that aberrant functioning of the ubiquitin-proteasome system (UPS) plays a crucial role in the initiation and progression of PD. Notably, E3 ubiquitin ligases serve as pivotal components determining substrate specificity within UPS and are intimately associated with the regulation of various proteins implicated in PD pathology. This review comprehensively summarizes the mechanisms by which E3 ubiquitin ligases and deubiquitinating enzymes modulate PD-associated proteins and signaling pathways, while exploring the intricate relationship between UPS dysfunctions and PD etiology. Furthermore, this article discusses recent research advancements regarding inhibitors targeting PD-related E3 ubiquitin ligases.
PubMed: 38931449
DOI: 10.3390/ph17060782 -
Plants (Basel, Switzerland) Jun 2024Plants utilize the ubiquitin proteasome system (UPS) to orchestrate numerous essential cellular processes, including the rapid responses required to cope with abiotic...
Plants utilize the ubiquitin proteasome system (UPS) to orchestrate numerous essential cellular processes, including the rapid responses required to cope with abiotic and biotic stresses. The 26S proteasome serves as the central catalytic component of the UPS that allows for the proteolytic degradation of ubiquitin-conjugated proteins in a highly specific manner. Despite the increasing number of studies employing cell-free degradation assays to dissect the pathways and target substrates of the UPS, the precise extraction methods of highly potent tissues remain unexplored. Here, we utilize a fluorogenic reporting assay using two extraction methods to survey proteasomal activity in different tissues. This study provides new insights into the enrichment of activity and varied presence of proteasomes in specific plant tissues.
PubMed: 38931128
DOI: 10.3390/plants13121696 -
Antioxidants (Basel, Switzerland) May 2024Carfilzomib is an irreversible proteasome inhibitor used for multiple myeloma patients. However, carfilzomib treatment is associated with cardiovascular complications....
Carfilzomib is an irreversible proteasome inhibitor used for multiple myeloma patients. However, carfilzomib treatment is associated with cardiovascular complications. Empagliflozin, an Sodium Glucose Co-transporter 2 inhibitor (SGLT-2) inhibitor, is an oral antidiabetic drug with proven antioxidant and anti-inflammatory properties. The aim of the present study was to determine the cardioprotective effects of empagliflozin against carfilzomib-induced cardiotoxicity. C57BL/6 mice were randomly divided into four groups: control, empagliflozin, carfilzomib, and carfilzomib + empagliflozin. Empagliflozin prevented carfilzomib-induced cardiotoxicity by ameliorating histological alterations, CK-MB, and troponin-I. Moreover, it inhibited carfilzomib-induced oxidative damage and inflammation via its action on catalase activity, reduced glutathione levels and superoxide dismutase activity, and reduced nuclear factor-κB (p65) and cytokine levels. Mechanistically, empagliflozin abrogated endoplasmic reticulum stress induced by carfilzomib, as evidenced by the effect on the Glucose Regulated Protein-78 (GRP-78)/Activating Transcription Factor 6 (ATF6)/C/EBP homologous protein (CHOP) axis. Intriguingly, carfilzomib significantly induced autophagy, an effect that was further enhanced by empagliflozin, evidenced by increased LC3B and beclin-1 mRNA expression and reduced p62 expression. The effect of empagliflozin on apoptosis was confirmed by reduced expression of active caspase-3. Importantly, empagliflozin did not alter the cytotoxic effect of carfilzomib on human U266B1 multiple myeloma cells. our findings suggest that empagliflozin may provide a new therapeutic strategy to mitigate carfilzomib-induced cardiotoxicity in multiple myeloma patients.
PubMed: 38929110
DOI: 10.3390/antiox13060671 -
International Journal of Molecular... Jun 2024The SPRY domain-containing SOCS box proteins SPSB1, SPSB2, and SPSB4 utilize their SPRY/B30.2 domain to interact with a short region in the N-terminus of inducible...
The SPRY domain-containing SOCS box proteins SPSB1, SPSB2, and SPSB4 utilize their SPRY/B30.2 domain to interact with a short region in the N-terminus of inducible nitric oxide synthase (iNOS), and recruit an E3 ubiquitin ligase complex to polyubiquitinate iNOS, resulting in the proteasomal degradation of iNOS. Inhibitors that can disrupt the endogenous SPSB-iNOS interactions could be used to augment cellular NO production, and may have antimicrobial and anticancer activities. We previously reported the rational design of a cyclic peptide inhibitor, cR8, cyclo(RGDINNNV), which bound to SPSB2 with moderate affinity. We, therefore, sought to develop SPSB inhibitors with higher affinity. Here, we show that cyclic peptides cR7, cyclo(RGDINNN), and cR9, cyclo(RGDINNNVE), have ~6.5-fold and ~2-fold, respectively, higher SPSB2-bindng affinities than cR8. We determined high-resolution crystal structures of the SPSB2-cR7 and SPSB2-cR9 complexes, which enabled a good understanding of the structure-activity relationships for these cyclic peptide inhibitors. Moreover, we show that these cyclic peptides displace full-length iNOS from SPSB2, SPSB1, and SPSB4, and that their inhibitory potencies correlate well with their SPSB2-binding affinities. The strongest inhibition was observed for cR7 against all three iNOS-binding SPSB proteins.
Topics: Peptides, Cyclic; Humans; Suppressor of Cytokine Signaling Proteins; Nitric Oxide Synthase Type II; Oligopeptides; Protein Binding; Structure-Activity Relationship
PubMed: 38928469
DOI: 10.3390/ijms25126764 -
International Journal of Molecular... Jun 2024Glucocerebrosidase (GCase) is a lysosomal enzyme that catalyzes the breakdown of glucosylceramide in the presence of its activator saposin C (SapC). SapC arises from the...
Glucocerebrosidase (GCase) is a lysosomal enzyme that catalyzes the breakdown of glucosylceramide in the presence of its activator saposin C (SapC). SapC arises from the proteolytical cleavage of prosaposin (encoded by gene), which gives rise to four saposins. GCase is targeted to the lysosomes by LIMP-2, encoded by gene. GCase deficiency causes Gaucher Disease (GD), which is mainly due to biallelic pathogenetic variants in the GCase-encoding gene, . However, impairment of GCase activity can be rarely caused by SapC or LIMP-2 deficiencies. We report a new case of LIMP-2 deficiency and a new case of SapC deficiency (missing all four saposins, PSAP deficiency), and measured common biomarkers of GD and GCase activity. Glucosylsphingosine and chitotriosidase activity in plasma were increased in GCase deficiencies caused by and mutations, whereas -linked deficiency showed only Glucosylsphingosine elevation. GCase activity was reduced in fibroblasts and leukocytes: the decrease was sharper in - and -mutant fibroblasts than -mutant ones; LIMP-2-deficient leukocytes displayed higher residual GCase activity than -mutant ones. Finally, we demonstrated that GCase mainly undergoes proteasomal degradation in LIMP-2-deficient fibroblasts and lysosomal degradation in PSAP-deficient fibroblasts. Thus, we analyzed the differential biochemical profile of GCase deficiencies due to the ultra-rare and biallelic pathogenic variants in comparison with the profile observed in -linked GCase deficiency.
Topics: Glucosylceramidase; Humans; Gaucher Disease; Saposins; Lysosomal Membrane Proteins; Receptors, Scavenger; Fibroblasts; Mutation; Lysosomes; Hexosaminidases; Male; Female
PubMed: 38928321
DOI: 10.3390/ijms25126615 -
International Journal of Molecular... Jun 2024Hepatitis B virus (HBV) infects approximately 300 million people worldwide, causing chronic infections. The HBV X protein (HBx) is crucial for viral replication and...
Hepatitis B virus (HBV) infects approximately 300 million people worldwide, causing chronic infections. The HBV X protein (HBx) is crucial for viral replication and induces reactive oxygen species (ROS), leading to cellular damage. This study explores the relationship between HBx-induced ROS, p53 activation, and HBV replication. Using HepG2 and Hep3B cell lines that express the HBV receptor NTCP, we compared ROS generation and HBV replication relative to p53 status. Results indicated that HBV infection significantly increased ROS levels in p53-positive HepG2-NTCP cells compared to p53-deficient Hep3B-NTCP cells. Knockdown of p53 reduced ROS levels and enhanced HBV replication in HepG2-NTCP cells, whereas p53 overexpression increased ROS and inhibited HBV replication in Hep3B-NTCP cells. The ROS scavenger N-acetyl-L-cysteine (NAC) reversed these effects. The study also found that ROS-induced degradation of the HBx is mediated by the E3 ligase Siah-1, which is activated by p53. Mutations in p53 or inhibition of its transcriptional activity prevented ROS-mediated HBx degradation and HBV inhibition. These findings reveal a p53-dependent negative feedback loop where HBx-induced ROS increases p53 levels, leading to Siah-1-mediated HBx degradation and HBV replication inhibition. This study offers insights into the molecular mechanisms of HBV replication and identifies potential therapeutic targets involving ROS and p53 pathways.
Topics: Humans; Tumor Suppressor Protein p53; Hepatitis B virus; Reactive Oxygen Species; Virus Replication; Trans-Activators; Viral Regulatory and Accessory Proteins; Hep G2 Cells; Liver Neoplasms; Carcinoma, Hepatocellular; Ubiquitin-Protein Ligases; Nuclear Proteins; Cell Line, Tumor
PubMed: 38928309
DOI: 10.3390/ijms25126606 -
International Journal of Molecular... Jun 2024Chronic obstructive pulmonary disease (COPD) is commonly caused from smoking cigarettes that induce biological stress responses. Previously we found disorganized...
Chronic obstructive pulmonary disease (COPD) is commonly caused from smoking cigarettes that induce biological stress responses. Previously we found disorganized endoplasmic reticulum (ER) in fibroblasts from COPD with different responses to chemical stressors compared to healthy subjects. Here, we aimed to investigate differences in stress-related gene expressions within lung cells from COPD and healthy subjects. Bronchoalveolar lavage (BAL) cells were collected from seven COPD and 35 healthy subjects. Lung fibroblasts were derived from 19 COPD and 24 healthy subjects and exposed to cigarette smoke extract (CSE). Gene and protein expression and cell proliferation were investigated. Compared to healthy subjects, we found lower gene expression of CHOP in lung fibroblasts from COPD subjects. Exposure to CSE caused inhibition of lung fibroblast proliferation in both groups, though the changes in ER stress-related gene expressions (ATF6, IRE1, PERK, ATF4, CHOP, BCL2L1) and genes relating to proteasomal subunits mostly occurred in healthy lung fibroblasts. No differences were found in BAL cells. In this study, we have found that lung fibroblasts from COPD subjects have an atypical ER stress gene response to CSE, particularly in genes related to apoptosis. This difference in response to CSE may be a contributing factor to COPD progression.
Topics: Humans; Pulmonary Disease, Chronic Obstructive; Fibroblasts; Endoplasmic Reticulum Stress; Male; Female; Middle Aged; Lung; Bronchoalveolar Lavage Fluid; Aged; Cell Proliferation; Gene Expression Regulation; Cells, Cultured; Apoptosis; Case-Control Studies
PubMed: 38928305
DOI: 10.3390/ijms25126600 -
International Journal of Molecular... Jun 2024The peripheral nervous system can encounter alterations due to exposure to some of the most commonly used anticancer drugs (platinum drugs, taxanes, vinca alkaloids,... (Review)
Review
The peripheral nervous system can encounter alterations due to exposure to some of the most commonly used anticancer drugs (platinum drugs, taxanes, vinca alkaloids, proteasome inhibitors, thalidomide), the so-called chemotherapy-induced peripheral neurotoxicity (CIPN). CIPN can be long-lasting or even permanent, and it is detrimental for the quality of life of cancer survivors, being associated with persistent disturbances such as sensory loss and neuropathic pain at limb extremities due to a mostly sensory axonal polyneuropathy/neuronopathy. In the state of the art, there is no efficacious preventive/curative treatment for this condition. Among the reasons for this unmet clinical and scientific need, there is an uncomplete knowledge of the pathogenetic mechanisms. Ion channels and transporters are pivotal elements in both the central and peripheral nervous system, and there is a growing body of literature suggesting that they might play a role in CIPN development. In this review, we first describe the biophysical properties of these targets and then report existing data for the involvement of ion channels and transporters in CIPN, thus paving the way for new approaches/druggable targets to cure and/or prevent CIPN.
Topics: Humans; Antineoplastic Agents; Peripheral Nervous System Diseases; Ion Channels; Animals; Neurotoxicity Syndromes; Membrane Transport Proteins; Neoplasms
PubMed: 38928257
DOI: 10.3390/ijms25126552 -
International Journal of Molecular... Jun 2024Proteasome 26S Subunit, Non-ATPase 9 () plays an important role in the balance of protamine and the stability of the nucleolar structure during spermatogenesis. In this...
Proteasome 26S Subunit, Non-ATPase 9 () plays an important role in the balance of protamine and the stability of the nucleolar structure during spermatogenesis. In this study, we cloned the of and analyzed its expression pattern. was identified on the Z chromosome of , which is considered an interesting candidate gene for spermatogenesis. qRT-PCR and FISH experiments showed that the gene was significantly highly expressed in the testes. It is worth noting that the expression level of in male fish testes is significantly higher than that in pseudomales. In order to further explore the role of in spermatogenesis, a male testicular cell line was used as the experimental material. The results of the -RNAi and overexpression experiments showed that had a synergistic effect with spermatogenesis-related genes , , and , but had an antagonistic effect with . Our findings offer a scientific foundation for comprehending the role of in the spermatogenesis regulatory network of .
Topics: Animals; Spermatogenesis; Male; Testis; Sex Chromosomes; Fish Proteins; Proteasome Endopeptidase Complex; Cloning, Molecular
PubMed: 38928079
DOI: 10.3390/ijms25126372 -
Genes Jun 2024We conducted transcriptome sequencing on salt-tolerant mutants X5 and X3, and a control (Ctr) strain of after treatment with artificial seawater at varying salinities...
We conducted transcriptome sequencing on salt-tolerant mutants X5 and X3, and a control (Ctr) strain of after treatment with artificial seawater at varying salinities (30‱, 45‱, and 60‱) for 3 weeks. Differentially expressed genes were identified and a weighted co-expression network analysis was conducted. The blue, red, and tan modules were most closely associated with salinity, while the black, cyan, light cyan, and yellow modules showed a close correlation with strain attributes. KEGG enrichment of genes from the aforementioned modules revealed that the key enrichment pathways for salinity attributes included the proteasome and carbon fixation in photosynthesis, whereas the key pathways for strain attributes consisted of lipid metabolism, oxidative phosphorylation, soluble N-ethylmaleimide-sensitive factor-activating protein receptor (SNARE) interactions in vesicular transport, and porphyrin and chlorophyll metabolism. Gene expression for the proteasome and carbon fixation in photosynthesis was higher in all strains at 60‱. In addition, gene expression in the proteasome pathway was higher in the X5-60 than Ctr-60 and X3-60. Based on the above data and relevant literature, we speculated that mutant X5 likely copes with high salt stress by upregulating genes related to lysosome and carbon fixation in photosynthesis. The proteasome may be reset to adjust the organism's proteome composition to adapt to high-salt environments, while carbon fixation may aid in maintaining material and energy metabolism for normal life activities by enhancing carbon dioxide uptake via photosynthesis. The differences between the X5-30 and Ctr-30 expression of genes involved in the synthesis of secondary metabolites, oxidative phosphorylation, and SNARE interactions in vesicular transport suggested that the X5-30 may differ from Ctr-30 in lipid metabolism, energy metabolism, and vesicular transport. Finally, among the key pathways with good correlation with salinity and strain traits, the key genes with significant correlation with salinity and strain traits were identified by correlation analysis.
Topics: Salt Tolerance; Transcriptome; Gene Regulatory Networks; Salinity; Photosynthesis; Osmotic Pressure; Proteasome Endopeptidase Complex; Gene Expression Profiling; Lipid Metabolism
PubMed: 38927717
DOI: 10.3390/genes15060781