Inhibition of NLRP3 inflammasome ameliorates LPS-induced neuroinflammatory injury in mice via PINK1/Parkin pathway.

Parkinson's disease (PD) is characterized by the severe loss of dopaminergic neurons in the substantia nigra pars compacta, leading to motor dysfunction. The onset of PD is often accompanied by neuroinflammation and α-Synuclein aggregation, and extensive research has focused on the activation of microglial NLRP3 inflammasomes in PD, which promotes the death of dopaminergic neurons. In this study, a model of cerebral inflammatory response was constructed in wild-type and Parkin＋/－ mice through bilateral intraventricular injection of LPS. LPS-induced activation of the NLRP3 inflammasome in wild-type mice promotes the progression of PD. The use of MCC950 in wild mice injected with LPS induces activation of Parkin/PINK and improves autophagy, which in turn improves mitochondrial turnover. It also inhibits LPS-induced inflammatory responses, improves motor function, protects dopaminergic neurons, and inhibits microglia activation. Furthermore, Parkin＋/－ mice exhibited motor dysfunction, loss of dopaminergic neurons, activation of the NLRP3 inflammasome, and α-Synuclein aggregation beginning at an early age. Parkin ± mice exhibited more pronounced microglia activation, greater NLRP3 inflammasome activation, more severe autophagy dysfunction, and more pronounced motor dysfunction after LPS injection compared to wild-type mice. Notably, the use of MCC950 in Parkin ± mice did not ameliorate NLRP3 inflammasome activation, autophagy dysfunction, or α-synuclein aggregation. Thus, MCC950 can only exert its effects in the presence of Parkin/PINK1, and targeting Parkin-mediated NLRP3 inflammasome activation is expected to be a potential therapeutic strategy for Parkinson's disease.

Ubiquitin ligase RFWD2 promotes dendritic spine and synapse formation by activating the ERK/PEA3/c-Jun pathway in rat cerebral cortical neurons.

The regulation of protein degradation through the ubiquitin-proteasome system is essential for normal brain development, axon growth, synaptic growth and plasticity. The E3 ubiquitin ligase RFWD2 plays a key role in the onset and development of neurological diseases, including the pathogenesis of Alzheimer's disease (AD), but the mechanisms controlling the homeostasis of neuronal synaptic proteins are still poorly understood. Here, we showed that the expression level of RFWD2 gradually decreased with the age of the rats and was negatively correlated with the development of cerebral cortical neurons and dendrites in vivo. RFWD2 was shown to localize to presynaptic terminals and some postsynaptic sides of both excitatory synapses and inhibitory synapses via colocalization with neuronal synaptic proteins (SYN, PSD95, Vglut1 and GAD67). Overexpression of RFWD2 promoted dendrite development and dendritic spine formation and markedly decreased the expression of synaptophysin and PSD95 by reducing the expression of ETV1, ETV4, ETV5 and c-JUN in vitro. Furthermore, the whole-cell membrane slice clamp results showed that RFWD2 overexpression resulted in greater membrane capacitance in neuronal cells, inadequate cell repolarization, and a longer time course for neurons to emit action potentials with decreased excitability. RFWD2 regulates dendritic development and plasticity, dendritic spine formation and synaptic function in rat cerebral cortex neurons by activating the ERK/PEA3/c-Jun pathway via a posttranslational regulatory mechanism and can be used as an efficient treatment target for neurological diseases.

The Combination of Age, International Standardized Ratio, Albumin and γ-Glutamyl Transpeptidase (AIAG), Tumor Size and Alpha Fetoprotein (AFP) Stage as the Prognostic Model for Hepatitis B-Related Hepatocellular Carcinoma.

BACKGROUND: Advanced liver fibrosis can lead to cirrhosis, portal hypertension and liver failure. Besides, advanced liver fibrosis and cirrhosis are the major risk factors for hepatocellular carcinoma (HCC). Almost all patients with HCC also have liver cirrhosis. This study aims to predict the survival rate of hepatitis B-related hepatocellular carcinoma (HCC) by age, international standardized ratio, albumin and γ-glutamyl transpeptidase (AIAG), an indicator measuring the degree of cirrhosis. METHODS: A total of 501 hepatitis B-related HCC patients experiencing radical surgery were analyzed, retrospectively. General data about demographics and labs were collected at the date of diagnosis to calculate AIAG [age, international standardized ratio (INR), albumin and gamma-glutamyl transferase (GGT)]. The Kaplan-Meier curves and Cox analysis were used to evaluate overall survival (OS) and recurrence-free survival (RFS). The C-index was calculated in R software (version 4.0.3) to evaluate the accuracy of the prognostic model. RESULTS: During a median follow-up period of 30 months, 31.1% (156/501) of the patients died, and 34.3% (172/501) experienced the recurrence of HCC. Compared with patients with lower AIAG score, patients with higher AIAG score had higher Child-Pugh grade and were at higher Barcelona Clinic Liver Cancer (BCLC) stage (both P<0.05). Multivariate analysis suggested that GGT, alpha fetoprotein (AFP), tumor size, BCLC stage and AIAG grade were independent predictors of OS and RFS. Furthermore, the combined use of tumor size, AFP and AIAG stage could predict survival significantly better (C-index=0.710, 95% CI: 0.669-0.751) than BCLC stage. CONCLUSION: AIAG is significantly associated with survival of HCC patients, and provides additional prognostic information for patients with HCC. Our findings suggest that the combination of AIAG, tumor size and AFP stage has a better predictive value for the prognosis of patients with hepatitis B-related hepatocellular carcinoma. However, it is necessary for more external evidences to determine clinical utility.