Nicotinamide ameliorates mitochondria-related neuronal apoptosis and cognitive impairment via the NAD+/SIRT3 pathway.

Emerging evidence suggests that mitochondria play a central role in mental health disorders including schizophrenia. Here we investigated whether nicotinamide (NAM) normalized cognitive impairment via a mechanism involving the mitochondrial Sirtuin 3 (SIRT3) pathway. The 24 h maternal separation (MS) rat model was used to mimic schizophrenia-associate phenotypes. Schizophrenia-like behaviors and memory impairments were detected using the pre-pulse inhibition test, novel object recognition test, and Barnes maze test, and neuronal apoptosis was characterized using multiple assays. SIRT3 activity was inhibited pharmacologically or by knockdown in HT22 cells, and BV2 microglia and SIRT3-knockdown HT22 cells were co-cultured in vitro. Mitochondrial molecules were measured by western blotting, and mitochondrial damage was measured with reactive oxygen species and mitochondrial membrane potential assays. Proinflammatory cytokines were assayed by ELISA and microglial activation was detected by immunofluorescence. MS animals showed behavioral and cognitive impairment and increased neuronal apoptosis. Supplementation with NAM or administration of honokiol, a SIRT3 activator, reversed all of the changes in behavioral and neuronal phenotypes. Administration of the SIRT3 inhibitor 3-TYP in control and NAM-treated MS rats caused behavioral and neuronal phenotypes similar to MS. In vitro, inhibition of SIRT3 activity with 3-TYP or by knockdown in HT22 cells increased ROS accumulation and caused neuronal apoptosis in a single-culture system. In co-culture systems, SIRT3 knockdown in HT22 cells activated BV2 microglia and increased levels of TNF-α, IL-6, and IL-1ß. The administration of NAM blocked these alterations. Taken together, these data suggest that NAM can rescue neuronal apoptosis and microglial over-activation through the nicotinamide adenine dinucleotide (NAD+)-SIRT3-SOD2 signaling pathway, furthering our understanding of the pathogenesis of schizophrenia and providing avenues for novel treatments.

Ursolic acid nanoparticles for glioblastoma therapy.

BACKGROUND: Glioblastoma multiforme (GBM) is the most common and fatal primary tumor in the central nervous system (CNS). The effect of chemotherapy of GBM is limited due to the existence of blood-brain barrier (BBB). The aim of this study is to develop self-assembled nanoparticles (NPs) of ursolic acid (UA) for GBM treatment. METHODS: UA NPs were synthesized by solvent volatilization method. Western blot analysis fluorescent staining and flow cytometry were launched to explore the anti-glioblastoma mechanism of UA NPs. The antitumor effects of UA NPs were further confirmed in vivo using intracranial xenograft models. RESULTS: UA were successfully prepared. In vitro, UA NPs could significantly increase the protein levels of cleaved-caspase 3 and LC3-II to strongly eliminate glioblastoma cells through autophagy and apoptosis. In the intracranial xenograft models, UA NPs could further effectively enter the BBB, and greatly improve the survival time of the mice. CONCLUSIONS: We successfully synthesized UA NPs which could effectively enter the BBB and show strong anti-tumor effect which may have great potential in the treatment of human glioblastoma.

BZW1 as an oncogene is associated with patient prognosis and the immune microenvironment in glioma.

BACKGROUND: Glioma is the most common primary tumor in the human central nervous system. This study was designed to explore the expression of BZW1 in glioma and its relevance to the clinicopathological features and outcome of glioma patients. METHODS: Glioma transcription profiling data were obtained from The Cancer Genome Atlas (TCGA). TIMER2, GEPIA2, GeneMANIA, and Metascape were searched in the present study. Cell and animal experiments were conducted to verify the effect of BZW1 on glioma cell migration in vitro and in vivo. Transwell assays, western blotting and immunofluorescence assays were performed. RESULTS: We found that BZW1 was highly expressed in gliomas and correlated with poor prognosis. BZW1 could promote glioma proliferation. GO/KEGG analysis revealed that BZW1 was involved in collagen-containing extracellular matrix and was correlated with ECM-receptor interactions, transcriptional misregulation in cancer and the IL-17 signaling pathway. In addition, BZW1 was also associated with the glioma tumor immune microenvironment. CONCLUSION: BZW1 can promote glioma proliferation and progression, and its high expression is correlated with a poor prognosis. BZW1 is also associated with the tumor immune microenvironment of glioma. This study may facilitate further understanding of the critical role of BZW1 in human tumors, including gliomas.

The RNA-binding protein CSTF2 regulates BAD to inhibit apoptosis in glioblastoma.

RNA-binding proteins (RBP) regulate several aspects of co- and post-transcriptional gene expression in cancer cells. CSTF2 is involved in the expression of many cellular mRNAs and involved in the 3'-end cleavage and polyadenylation of pre-mRNAs to terminate transcription. However, the role of CSTF2 in human glioblastoma (GBM) and the underlying mechanisms remain unclear. In the present study, CSTF2 was found to be upregulated in GBM, and its high expression predicted poor prognosis. Knockdown CSTF2 induced GBM cell apoptosis both in vitro and in vivo. Specific mechanism studies showed that CSTF2 unstabilized the mRNA of the BAD protein by shortening its 3' UTR. Additionally, an increase in the expression level of CSTF2 decreased the expression level of BAD. In conclusion, CSTF2 binds to the mRNA of the BAD protein to shorten its 3'UTR, which negatively affects the BAD mediated apoptosis and promotes GBM cell survival.

Esterase-responsive and size-optimized prodrug nanoparticles for effective intracranial drug delivery and glioblastoma treatment.

Glioblastoma multiforme (GBM) is the intracranial malignancy with the highest rates of morbidity and mortality. Chemotherapy is often ineffective against GBM due to the presence of the blood-brain barrier (BBB); however, the application of nanotechnology is expected to overcome this limitation. Poly(lactic-co-glycolic acid) (PLGA) is a degradable and nontoxic functional polymer with good biocompatibility that is widely used in the pharmaceutical industry. Previous studies have shown that the ability of PLGA nanoparticles (NPs) to penetrate the BBB is largely determined by their size; however, determination of the optimal PLGA NP size requires further research. Here, we report a tandutinib-based prodrug (proTan), which responds to the GBM microenvironment, that was combined with NPs to overcome the BBB. AMD3100-PLGA NPs loaded with proTan inhibited tumor growth and effectively prolonged the survival of tumor-bearing mice.

TMBIM1 promotes proliferation and attenuates apoptosis in glioblastoma cells by targeting the p38 MAPK signalling pathway.

Glioblastoma multiforme (GBM) is the most common and most fatal primary malignant brain tumour in adults. The average survival time of patients after diagnosis is only 12-15 months. And its characteristics of excessive proliferation and apoptosis evasion play a crucial role in the poor prognosis of patients. Therefore, it is worth investigating the molecular mechanism of GBM to find an effective therapeutic target to overcome the dilemma. In the current study, Transmembrane BAX inhibitor motif containing 1 (TMBIM1) was highly expressed in GBM tissues and high TMBIM1 expression in GBM cell lines (U87 and U251) could promote cell proliferation and inhibit cell cycle arrest. In addition, TMBIM1 could significantly attenuate GBM cell apoptosis and decrease the sensitivity of GBM cells to temozolomide (TMZ). In terms of the molecular mechanism, we revealed that TMBIM1 interferes with the p38/MAPK pathway by inhibiting p38 phosphorylation to promote cell proliferation and attenuate cell apoptosis. In vivo experiments showed that the survival time of mice in TMBIM1 knockdown group was significantly prolonged. Our discovery provided an important basis for future intensive molecular mechanism research in GBM and presented a potential target for the treatment of GBM.

Betulinic acid self-assembled nanoparticles for effective treatment of glioblastoma.

BACKGROUND: Glioblastoma (GBM) is the most common and fatal primary tumor in the central nervous system (CNS). Due to the existence of blood-brain barrier (BBB), most therapeutics cannot efficiently reach tumors in the brain, and as a result, they are unable to be used for effective GBM treatment. Accumulating evidence shows that delivery of therapeutics in form of nanoparticles (NPs) may allow crossing the BBB for effective GBM treatment. METHODS: Betulinic acid NPs (BA NPs) were synthesized by the standard emulsion approach and characterized by electron microscopy and dynamic light scattering analysis. The resulting NPs were characterized for their anti-tumor effects by cell viability assay, EdU-DNA synthesis assay, cell cycle assay, mitochondrial membrane potential, and PI-FITC apoptosis assay. Further mechanistic studies were carried out through Western Blot and immunostaining analyses. Finally, we evaluated BA NPs in vivo for their pharmacokinetics and antitumor effects in intracranial xenograft GBM mouse models. RESULTS: BA NPs were successfully prepared and formed into rod shape. BA NPs could significantly suppress glioma cell proliferation, induce apoptosis, and arrest the cell cycle in the G0/G1 phase in vitro. Furthermore, BA NPs downregulated the Akt/NFκB-p65 signaling pathway in a concentration dependent manner. We found that the observed anti-tumor effect of BA NPs was dependent on the function of CB1/CB2 receptors. Moreover, in the intracranial GBM xenograft mouse models, BA NPs could effectively cross the BBB and greatly prolong the survival time of the mice. CONCLUSIONS: We successfully synthesized BA NPs, which could cross the BBB and demonstrated a strong anti-tumor effect. Therefore, BA NPs may potentially be used for effective treatment of GBM.

Enriched Environment Attenuates Pyroptosis to Improve Functional Recovery After Cerebral Ischemia/Reperfusion Injury.

Enriched environment (EE) is a complex containing social, cognitive, and motor stimuli. Exposure to EE can promote functional recovery after ischemia/reperfusion (I/R) injury. However, the underlying mechanisms remained unclear. Pyroptosis has recently been identified and demonstrated a significant role in ischemic stroke. The purpose of this study was to explore the effect of EE on neuronal pyroptosis after cerebral I/R injury. In the current study, middle cerebral artery occlusion/reperfusion (MCAO/R) was applied to establish the cerebral I/R injury model. Behavior tests including the modified Neurological Severity Scores (mNSS) and the Morris Water Maze (MWM) were performed. The infarct volume was evaluated by Nissl staining. To evaluate the levels of pyroptosis-related proteins, the levels of GSDMD-N and nod-like receptor protein 1/3 (NLRP1/3) inflammasome-related proteins were examined. The mRNA levels of IL-1ß and IL-18 were detected by Quantitative Real-Time PCR (qPCR). The secretion levels of IL-1ß and IL-18 were analyzed by ELISA. Also, the expression of p65 and p-p65 were detected. The results showed that EE treatment improved functional recovery, reduced infarct volume, attenuated neuronal pyroptosis after cerebral I/R injury. EE treatment also suppressed the activities of NLRP1/NLRP3 inflammasomes. These may be affected by inhabiting the NF-κB p65 signaling pathway. Our findings suggested that neuronal pyroptosis was probably the neuroprotective mechanism that EE treatment rescued neurological deficits after I/R injury.

WAC, a novel GBM tumor suppressor, induces GBM cell apoptosis and promotes autophagy.

WAC is closely related to the occurrence and development of tumors. However, its role in human glioblastoma (GBM) and its potential regulatory mechanisms have not been investigated. This study demonstrated that WAC is downregulated in GBM, and its low expression predicts a poor prognosis. We investigated the effect of WAC on the proliferation of glioma cells through a CCK-8 assay, EdU incorporation, and cell formation. The effects of WAC on apoptosis and autophagy in glioma were determined by flow cytometry, TUNEL detection, immunofluorescence, q-PCR, WB, and scanning electron microscopy. We found that overexpression of WAC inhibited the proliferation of glioma cells, promoted apoptosis, and induced autophagy. Therefore, WAC is likely to play a role as a new regulatory molecule in glioma.

The New PI3K/mTOR Inhibitor GNE-477 Inhibits the Malignant Behavior of Human Glioblastoma Cells.

The most common primary central nervous system tumor in adults is glioblastoma multiforme (GBM). The high invasiveness of GBM cells is an important factor leading to inevitable tumor recurrence and a poor prognosis of patients. GNE-477, a novel PI3K/mTOR inhibitor, has been reported to exert antiproliferative effects on other cancer cells. However, researchers have not clearly determined whether GNE-477 produces antitumor effects on GBM. In the present study, GNE-477 significantly inhibited the proliferation, migration and invasion of U87 and U251 cells. In addition, GNE-477 also induced apoptosis of GBM cells, arresting the cell cycle in G0/G1 phase. More importantly, GNE-477 also reduced the levels of AKT and mTOR phosphorylation in the AKT/mTOR signaling pathway in a concentration-dependent manner. An increase in AKT activity induced by SC79 rescued the GNE-477-mediated inhibition of GBM cell proliferation and apoptosis. The antitumor effects of GNE-477 and the regulatory effects on related molecules were further confirmed in vivo using a nude mouse intracranial xenograft model. In conclusion, our study indicated that GNE-477 exerted significant antitumor effects on GBM cells in vitro and in vivo by downregulating the AKT/mTOR pathway.

BIRB796, an Inhibitor of p38 Mitogen-Activated Protein Kinase, Inhibits Proliferation and Invasion in Glioblastoma Cells.

Glioblastoma (GBM) is the most common malignant tumor, and it is characterized by high cellular proliferation and invasion in the central nervous system of adults. Due to its high degree of heterogeneity and mortality, there is no effective therapy for GBM. In our study, we investigated the effect of the p38-MAPK signaling pathway inhibitor BIRB796 on GBM cells. Cell Counting Kit-8 (CCK-8) assay, 5-ethynyl-2'-deoxyuridine (EDU) staining, and cell cycle distribution analysis were performed, and the results showed that BIRB796 decreased proliferation in U87 and U251 cells. Moreover, wound healing and invasion assays were performed, which showed that BIRB796 inhibited the migration and invasion of human GBM cells. We found that BIRB796 treatment significantly decreased the formation of the cytoskeleton and thus downregulated the movement ability of the cells, as shown by phalloidin staining and vimentin immunofluorescence staining. Real-time polymerase chain reaction showed that the mRNA levels of MMP-2, Vimentin, CyclinD1, and Snail-1 were downregulated. Consistently, the expressions of MMP-2, Vimentin, CyclinD1, and p-p38 were also decreased after BIRB796 treatment. Taken together, all our results demonstrated that BIRB796 could play an antitumor role by inhibiting the proliferation and invasion in GBM cells. Thus, BIRB796 may be used as an adjuvant therapy to improve the therapeutic efficacy of GBM treatment.