作者: Angelin, Alessia ; Keith, Kelsey ; Widjaja, Gabrielle A ; Murdock, Deborah G ; Albrecht, Yentli E Soto ; Guarnieri, Joseph W ; Jurado, Kellie A ; Potluri, Prasanth ; Taylor, Deanne ; Zhu, Yi ; Kilbaugh, Todd J ; McManus, Meagan J ; Hewin, Peter ; Lie, Timothy ; Wallace, Douglas C

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection inhibits mitochondrial oxidative phosphorylation (OXPHOS) and elevates mitochondrial reactive oxygen species (ROS, mROS) which activates hypoxia-inducible factor-1alpha (HIF-1α), shifting metabolism toward glycolysis to drive viral biogenesis but also causing the release of mitochondrial DNA (mtDNA) and activation of innate immunity. To determine whether mitochondrially targeted antioxidants could mitigate these viral effects, we challenged mice expressing human angiotensin-converting enzyme 2 (ACE2) with SARS-CoV-2 and intervened using transgenic and pharmacological mitochondrially targeted catalytic antioxidants. Transgenic expression of mitochondrially targeted catalase (mCAT) or systemic treatment with EUK8 decreased weight loss, clinical severity, and circulating levels of mtDNA; as well as reduced lung levels of HIF-1α, viral proteins, and inflammatory cytokines. RNA-sequencing of infected lungs revealed that mCAT and Eukarion 8 (EUK8) up-regulated OXPHOS gene expression and down-regulated HIF-1α and its target genes as well as innate immune gene expression. These data demonstrate that SARS-CoV-2 pathology can be mitigated by catalytically reducing mROS, potentially providing a unique host-directed pharmacological therapy for COVID-19 which is not subject to viral mutational resistance.

2024-06-01·Journal of Pharmacological Sciences

Proteasome inhibitors induce apoptosis by superoxide anion generation via NADPH oxidase 5 in human neuroblastoma SH-SY5Y cells

Article

作者: Yoshioka, Yasuhiro ; Iyama, Takumi ; Ishimaru, Yuki ; Yamamuro-Tanabe, Akiko ; Oshima, Yu

The ubiquitin-proteasome system (UPS) is a major proteolytic system that plays an important role in the regulation of various cell processes, such as cell cycle, stress response, and transcriptional regulation, especially in neurons, and dysfunction of UPS is considered to be a cause of neuronal cell death in neurodegenerative diseases. However, the mechanism of neuronal cell death caused by UPS dysfunction has not yet been fully elucidated. In this study, we investigated the mechanism of neuronal cell death induced by proteasome inhibitors using human neuroblastoma SH-SY5Y cells. Z-Leu-D-Leu-Leu-al (MG132), a proteasome inhibitor, induced apoptosis in SH-SY5Y cells in a concentration- and time-dependent manner. Antioxidants N-acetylcysteine and EUK-8 attenuated MG132-induced apoptosis. Apocynin and diphenyleneiodonium, inhibitors of NADPH oxidase (NOX), an enzyme that produces superoxide anions, also attenuated MG132-induced apoptosis. It was also found that MG132 treatment increased the expression of NOX5, a NOX family member, and that siRNA-mediated silencing of NOX5 and BAPTA-AM, which inhibits NOX5 by chelating calcium, suppressed MG132-induced apoptosis and production of reactive oxygen species in SH-SY5Y cells. These results suggest that MG132 induces apoptosis in SH-SY5Y cells through the production of superoxide anion by NOX5.

2023-02-01·Journal of Cellular Biochemistry

Inhibition of sPLA₂ enzyme activity by cell‐permeable antioxidant EUK‐8 and downregulation of p38, Akt, and p65 signals induced by sPLA₂ in inflammatory mouse paw edema model

Article

作者: Manjuprasanna, Vaddarahally N. ; Rudresha, Gotravalli V. ; Vishwanath, Bannikuppe S. ; Gowda, M. D. Milan ; Nandana, Manuganahally Basavarajappa ; Bharatha, Madeva ; Urs, Amog P. ; Jayachandra, Krishnegowda ; Jameel, Noor Mohamed

AbstractThe arachidonic acid (AA) metabolic pathway, plays a vital role in the production of eicosanoids by the action of pro‐inflammatory secretory phospholipase A2 (PLA2). Release of eicosanoids is known to be involved in many inflammatory diseases. Identification of the inhibitory molecules of this AA pathway enzyme along with the regulation of intracellular signaling cascades may be a finer choice to develop as a powerful anti‐inflammatory drug. In this regard, we have screened few cell‐permeable antioxidant molecules Tempo, Mito‐TEMPO, N,N'‐Bis(salicylideneamino)ethane‐manganese(II) (EUK)‐134, and EUK‐8 against pro‐inflammatory sPLA2s. Among these, we found EUK‐8 is a potent inhibitor with its IC50 value ranges 0.7–2.0 µM for sPLA2s isolated from different sources. Furthermore, docking studies confirm the strong binding of EUK‐8 towards sPLA2. In vivo effect of EUK‐8 was studied in HSF‐sPLA2‐induced edema in mouse paw model. In addition to neutralizing the edema, EUK‐8 significantly reduces the phosphorylation level of inflammatory proteins such as p38 member of MAPK pathway, Akt, and p65 along with the suppression of pro‐inflammatory cytokine (interleukin‐6) and chemokine (CXCL1) in edematous tissue. This shows that EUK‐8 not only inhibits the sPLA2 activity, it also plays an important role in the regulation of sPLA2‐induced cell signaling cascades. Apart from the sPLA2 inhibition, we also examine the regulatory actions of EUK‐8 with other downstream enzymes of AA pathway such as 5‐LOX assay in human polymorphonuclear leukocytes (PMNs) and COX‐2 expression in carrageenan‐λ induced paw edema. Here EUK‐8 significantly inhibits 5‐LOX enzyme activity and downregulates COX‐2 expression. These data indicate that EUK‐8 found to be a promising multitargeted inhibitory molecule toward inflammatory pathway. In conclusion, mitochondrial targeted antioxidant EUK‐8 is not only the powerful antioxidant, also a potent anti‐inflammatory molecule and may be a choice of molecule for pharmacological applications.

100 项与 EUK-8 相关的药物交易

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