MZF1 alleviates oxidative stress and apoptosis induced by rotenone in SH-SY5Y cells by promoting RBM3 transcription

Lactoferrin-modified organic-inorganic hybrid mesoporous silica for co-delivery of levodopa and curcumin in the synergistic treatment of Parkinson's disease

BACKGROUND

Parkinson's disease (PD) is a chronic neurodegenerative disorder primarily characterized by oxidative stress and dopaminergic neuron damage. While levodopa remains the cornerstone of PD treatment, its efficacy is limited by poor bioavailability and neuroprotective effects. Curcumin, a potent antioxidant derived from turmeric, demonstrates neuroprotective promise but also suffers from low bioavailability, hindering its therapeutic application. The combined therapeutic use of levodopa and curcumin offers a potential synergistic approach, though its neuroprotection potential through brain-targeted delivery remains underexplored.

PURPOSE

To develop a lactoferrin-modified organic-inorganic hybrid mesoporous silica nanoparticle system (Lf-lip@LC-MSNs) for co-delivering levodopa and curcumin, aiming to enhance neuroprotective efficacy and achieve brain-targeted delivery in PD.

METHODS

Lf-lip@LC-MSNs were engineered to encapsulate levodopa within a curcumin-loaded lipid bilayer, modified with lactoferrin for optimized brain-targeted delivery. In vitro studies were conducted on rotenone-damaged neuronal models to evaluate oxidative stress, mitochondrial dysfunction, α-synuclein aggregation, and neuronal survival. In vivo experiments on MPTP-induced PD mouse models evaluated biodistribution, therapeutic efficacy, and safety in healthy mice, focusing on motor function recovery.

RESULTS

The combination of levodopa and curcumin significantly reduced oxidative stress and α-synuclein accumulation, enhancing neuronal survival compared to monotherapies. Lf-lip@LC-MSNs further amplified these effects, achieving superior brain-targeted delivery and improved motor function restoration with minimal systemic toxicity.

CONCLUSIONS

The combination of curcumin and levodopa provided synergistic neuroprotection in PD models. By employing a targeted delivery system, the Lf-lip@LC-MSNs not only facilitated efficient brain targeting but also potentiated therapeutic outcomes, providing a compelling strategy for treating PD and paving the way for advancements in managing other neurodegenerative diseases.

RBM3 interacts with Raptor to regulate autophagy and protect cardiomyocytes from ischemia-reperfusion-induced injury

Acute myocardial infarction (AMI) is a common disease with high morbidity and mortality worldwide. However, postinfarction pathogenesis remains unclear, and it is particularly important to identify new therapeutic targets. The RNA-binding motif protein RBM3 (also known as cold-inducible protein) is known to promote translation and is associated with tumor proliferation and neuroprotection. However, little is known about the biological effects of RBM3 on myocardial infarction. In the present study, we found that RBM3 expression was significantly upregulated in ischemia-reperfusion (I/R) condition and downregulation of RBM3 inhibited autophagy and promoted apoptosis in cardiomyocytes. We confirmed that RBM3 interacts with Raptor to regulate the autophagy pathway. Taken together, these findings illustrate the protective effects of RBM3 against I/R-induced myocardial apoptosis through the autophagy pathway.

RNA binding motif protein 3 (RBM3) promotes protein kinase B (AKT) activation to enhance glucose metabolism and reduce apoptosis in skeletal muscle of mice under acute cold exposure

The main danger of cold stress to animals in cold regions is systemic metabolic changes and protein synthesis inhibition. RBM3, an exceptional cold shock protein, is rapidly upregulated in response to hypothermia to resist the adverse effects of cold stress. However, the mechanism of the protective effect and the rapid upregulation of RBM3 remains unclear. O-GlcNAcylation, an atypical O-glycosylation, is precisely regulated only by O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA) and participates in the signal transduction of multiple cellular stress responses as a "stress and nutrition receptor." Therefore, our study aimed to explore the mechanism of RBM3 regulating glucose metabolism and promoting survival in skeletal muscle under acute cold exposure. Meanwhile, our study verifies whether O-GlcNAcylation mediated by OGT rapidly upregulates RBM3. The blood and skeletal muscle of mice were collected at the end of cold exposure treatment for 0, 2, and 4 h. Changes in levels of RBM3, AKT, glycolysis apoptosis, and OGT were measured. The results show that acute cold exposure upregulated RBM3, OGT, and AKT phosphorylation and increased energy consumption, which enhanced glycolysis and prevent apoptosis. In the 32 °C mild hypothermia model in vitro, overexpression of RBM3 enhanced AKT phosphorylation. Meanwhile, inactivation of AKT by wortmannin resulted in increased apoptosis and decreased glucose metabolism in skeletal muscle under acute cold exposure. In addition, OGT-mediated O-GlcNAcylation of p65 was confirmed in mouse myoblast cell line (C2C12) cells at mild hypothermia. O-GlcNAcylation level affected p65 activity and nuclear translocation. Compared with wild type (WT) mice, RBM3 and p65 phosphorylation were decreased in specific skeletal muscle Ogt (KO) mice, whereas AKT phosphorylation, glycolysis, and apoptosis were increased. Taken together, O-GlcNAcylation of p65 upregulates RBM3 to promote AKT phosphorylation, enhance glucose metabolism, and reduce apoptosis in skeletal muscle of mice under acute cold exposure.

Mild hypothermia ameliorates hepatic ischemia reperfusion injury by inducing RBM3 expression

Liver ischemia reperfusion injury (IRI) is a serious complication of certain liver surgeries, and it is difficult to prevent. As a potential drug-free treatment, mild hypothermia has been shown to promote positive outcomes in patients with IRI. However, the protective mechanism remains unclear. We established in vivo and in vitro models of hepatic ischemia reperfusion (IR) and mild hypothermia pretreatment. Hepatocytes were transfected with RNA-binding motif protein 3 (RBM3) overexpression plasmids, and IR was performed. Cell, culture medium, blood and tissue samples were collected to assess hepatic injury, oxidative stress, apoptosis and changes in RBM3 expression in the liver. Upregulation of RBM3 expression by mild hypothermia reduced the aminotransferase release, liver tissue injury and mitochondrial injury induced by liver IR. Hepatic IR-induced p38 and c-Jun N-terminal kinase (JNK) signaling pathway activation, oxidative stress injury and apoptosis could be greatly reversed by mild hypothermia. Overexpression of RBM3 mimicked the hepatoprotective effect of mild hypothermia. Mild hypothermia protects the liver from ischemia reperfusion-induced p38 and JNK signaling pathway activation, oxidative stress injury and apoptosis through the upregulation of RBM3 expression.