Tat-NOL3 protects against hippocampal neuronal cell death induced by oxidative stress through the regulation of apoptotic pathways

The atypical antidepressant tianeptine confers neuroprotection against oxygen-glucose deprivation

Proregenerative and neuroprotective effects of antidepressants are an important topic of inquiry in neuropsychiatric research. Oxygen-glucose deprivation (OGD) mimics key aspects of ischemic injury in vitro. Here, we studied the effects of 24-h pretreatment with serotonin (5-HT), citalopram (CIT), fluoxetine (FLU), and tianeptine (TIA) on primary mouse cortical neurons subjected to transient OGD. 5-HT (50 μM) significantly enhanced neuron viability as measured by MTT assay and reduced cell death and LDH release. CIT (10 μM) and FLU (1 μM) did not increase the effects of 5-HT and neither antidepressant conferred neuroprotection in the absence of supplemental 5-HT in serum-free cell culture medium. By contrast, pre-treatment with TIA (10 μM) resulted in robust neuroprotection, even in the absence of 5-HT. Furthermore, TIA inhibited mRNA transcription of candidate genes related to cell death and hypoxia and attenuated lipid peroxidation, a hallmark of neuronal injury. Finally, deep RNA sequencing of primary neurons subjected to OGD demonstrated that OGD induces many pathways relating to cell survival, the inflammation-immune response, synaptic dysregulation and apoptosis, and that TIA pretreatment counteracted these effects of OGD. In conclusion, this study highlights the comparative strength of the 5-HT independent neuroprotective effects of TIA and identifies the molecular pathways involved.

Long-term administration of morphine specifically alters the level of protein expression in different brain regions and affects the redox state

We investigated the changes in redox state and protein expression in selected parts of the rat brain induced by a 4 week administration of morphine (10 mg/kg/day). We found a significant reduction in lipid peroxidation that mostly persisted for 1 week after morphine withdrawal. Morphine treatment led to a significant increase in complex II in the cerebral cortex (Crt), which was accompanied by increased protein carbonylation, in contrast to the other brain regions studied. Glutathione levels were altered differently in the different brain regions after morphine treatment. Using label-free quantitative proteomic analysis, we found some specific changes in protein expression profiles in the Crt, hippocampus, striatum, and cerebellum on the day after morphine withdrawal and 1 week later. A common feature was the upregulation of anti-apoptotic proteins and dysregulation of the extracellular matrix. Our results indicate that the tested protocol of morphine administration has no significant toxic effect on the rat brain. On the contrary, it led to a decrease in lipid peroxidation and activation of anti-apoptotic proteins. Furthermore, our data suggest that long-term treatment with morphine acts specifically on different brain regions and that a 1 week drug withdrawal is not sufficient to normalize cellular redox state and protein levels.

Potential of oligonucleotide- and protein/peptide-based therapeutics in the management of toxicant/stressor-induced diseases

Exposure to toxicants/stressors has been linked to the development of many human diseases. They could affect various cellular components, such as DNA, proteins, lipids, and non-coding RNAs (ncRNA), thereby triggering various cellular pathways, particularly oxidative stress, inflammatory responses, and apoptosis, which can contribute to pathophysiological states. Accordingly, modulation of these pathways has been the focus of numerous investigations for managing related diseases. The involvement of various ncRNAs, such as small interfering RNA (siRNA), microRNAs (miRNA), and long non-coding RNAs (lncRNA), as well as various proteins and peptides in mediating these pathways, provides many target sites for pharmaceutical intervention. In this regard, various oligonucleotide- and protein/peptide-based therapies have been developed to treat toxicity-induced diseases, which have shown promising results in vitro and in vivo. This comprehensive review provides information about various aspects of toxicity-related diseases including their causing factors, main underlying mechanisms and intermediates, and their roles in pathophysiological states. Particularly, it highlights the principles and mechanisms of oligonucleotide- and protein/peptide-based therapies in the treatment of toxicity-related diseases. Furthermore, various issues of oligonucleotides and proteins/peptides for clinical usage and potential solutions are discussed.

Molecular signature to predict quality of life and survival with glioblastoma using Multiview omics model

Glioblastoma multiforme (GBM) patients show a variety of signs and symptoms that affect their quality of life (QOL) and self-dependence. Since most existing studies have examined prognostic factors based only on clinical factors, there is a need to consider the value of integrating multi-omics data including gene expression and proteomics with clinical data in identifying significant biomarkers for GBM prognosis. Our research aimed to isolate significant features that differentiate between short-term (≤ 6 months) and long-term (≥ 2 years) GBM survival, and between high Karnofsky performance scores (KPS ≥ 80) and low (KPS ≤ 60), using the iterative random forest (iRF) algorithm. Using the Cancer Genomic Atlas (TCGA) database, we identified 35 molecular features composed of 19 genes and 16 proteins. Our findings propose molecular signatures for predicting GBM prognosis and will improve clinical decisions, GBM management, and drug development.

The Dysfunction of Carcinogenesis- and Apoptosis-Associated Genes that Develops in the Hypothalamus under Chronic Social Defeat Stress in Male Mice

Chronic social stress caused by daily agonistic interactions in male mice leads to a mixed anxiety/depression-like disorder that is accompanied by the development of psychogenic immunodeficiency and stimulation of oncogenic processes concurrently with many neurotranscriptomic changes in brain regions. The aim of the study was to identify carcinogenesis- and apoptosis-associated differentially expressed genes (DEGs) in the hypothalamus of male mice with depression-like symptoms and, for comparison, in aggressive male mice with positive social experience. To obtain two groups of animals with the opposite 20-day social experiences, a model of chronic social conflict was used. Analysis of RNA-Seq data revealed similar expression changes for many DEGs between the aggressive and depressed animals in comparison with the control group; however, the number of DEGs was significantly lower in the aggressive than in the depressed mice. It is likely that the observed unidirectional changes in the expression of carcinogenesis- and apoptosis-associated genes in the two experimental groups may be a result of prolonged social stress (of different severity) caused by the agonistic interactions. In addition, 26 DEGs were found that did not change expression in the aggressive animals and could be considered genes promoting carcinogenesis or inhibiting apoptosis. Akt1, Bag6, Foxp4, Mapk3, Mapk8, Nol3, Pdcd10, and Xiap were identified as genes whose expression most strongly correlated with the expression of other DEGs, suggesting that their protein products play a role in coordination of the neurotranscriptomic changes in the hypothalamus. Further research into functions of these genes may be useful for the development of pharmacotherapies for psychosomatic pathologies.

Cell-penetrating peptide-mediated delivery of therapeutic peptides/proteins to manage the diseases involving oxidative stress, inflammatory response and apoptosis

OBJECTIVES

Peptides and proteins represent great potential for modulating various cellular processes including oxidative stress, inflammatory response, apoptosis and consequently the treatment of related diseases. However, their therapeutic effects are limited by their inability to cross cellular barriers. Cell-penetrating peptides (CPPs), which can transport cargoes into the cell, could resolve this issue, as would be discussed in this review.

KEY FINDINGS

CPPs have been successfully exploited in vitro and in vivo for peptide/protein delivery to treat a wide range of diseases involving oxidative stress, inflammatory processes and apoptosis. Their in vivo applications are still limited due to some fundamental issues of CPPs, including nonspecificity, proteolytic instability, potential toxicity and immunogenicity.

SUMMARY

Totally, CPPs could potentially help to manage the diseases involving oxidative stress, inflammatory response and apoptosis by delivering peptides/proteins that could selectively reach proper intracellular targets. More studies to overcome related CPP limitations and confirm the efficacy and safety of this strategy are needed before their clinical usage.

Prognostic value and immune relevancy of a combined autophagy-, apoptosis- and necrosis-related gene signature in glioblastoma

Background

Glioblastoma (GBM) is considered the most malignant and devastating intracranial tumor without effective treatment. Autophagy, apoptosis, and necrosis, three classically known cell death pathways, can provide novel clinical and immunological insights, which may assist in designing personalized therapeutics. In this study, we developed and validated an effective signature based on autophagy-, apoptosis- and necrosis-related genes for prognostic implications in GBM patients.

Methods

Variations in the expression of genes involved in autophagy, apoptosis and necrosis were explored in 518 GBM patients from The Cancer Genome Atlas (TCGA) database. Univariate Cox analysis, least absolute shrinkage and selection operator (LASSO) analysis, and multivariate Cox analysis were performed to construct a combined prognostic signature. Kaplan–Meier survival, receiver-operating characteristic (ROC) curves and Cox regression analyses based on overall survival (OS) and progression-free survival (PFS) were conducted to estimate the independent prognostic performance of the gene signature. The Chinese Glioma Genome Atlas (CGGA) dataset was used for external validation. Finally, we investigated the differences in the immune microenvironment between different prognostic groups and predicted potential compounds targeting each group.

Results

A 16-gene cell death index (CDI) was established. Patients were clustered into either the high risk or the low risk groups according to the CDI score, and those in the low risk group presented significantly longer OS and PFS than the high CDI group. ROC curves demonstrated outstanding performance of the gene signature in both the training and validation groups. Furthermore, immune cell analysis identified higher infiltration of neutrophils, macrophages, Treg, T helper cells, and aDCs, and lower infiltration of B cells in the high CDI group. Interestingly, this group also showed lower expression levels of immune checkpoint molecules PDCD1 and CD200, and higher expression levels of PDCD1LG2, CD86, CD48 and IDO1.

Conclusion

Our study proposes that the CDI signature can be utilized as a prognostic predictor and may guide patients’ selection for preferential use of immunotherapy in GBM.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09328-3.

Prognostic Significance of Autophagy-Relevant Gene Markers in Colorectal Cancer

Background

Colorectal cancer (CRC) is a common malignant solid tumor with an extremely low survival rate after relapse. Previous investigations have shown that autophagy possesses a crucial function in tumors. However, there is no consensus on the value of autophagy-associated genes in predicting the prognosis of CRC patients. This work screens autophagy-related markers and signaling pathways that may participate in the development of CRC, and establishes a prognostic model of CRC based on autophagy-associated genes.

Methods

Gene transcripts from the TCGA database and autophagy-associated gene data from the GeneCards database were used to obtain expression levels of autophagy-associated genes, followed by Wilcox tests to screen for autophagy-related differentially expressed genes. Then, 11 key autophagy-associated genes were identified through univariate and multivariate Cox proportional hazard regression analysis and used to establish prognostic models. Additionally, immunohistochemical and CRC cell line data were used to evaluate the results of our three autophagy-associated genes EPHB2, NOL3, and SNAI1 in TCGA. Based on the multivariate Cox analysis, risk scores were calculated and used to classify samples into high-risk and low-risk groups. Kaplan-Meier survival analysis, risk profiling, and independent prognosis analysis were carried out. Receiver operating characteristic analysis was performed to estimate the specificity and sensitivity of the prognostic model. Finally, GSEA, GO, and KEGG analysis were performed to identify the relevant signaling pathways.

Results

A total of 301 autophagy-related genes were differentially expressed in CRC. The areas under the 1-year, 3-year, and 5-year receiver operating characteristic curves of the autophagy-based prognostic model for CRC were 0.764, 0.751, and 0.729, respectively. GSEA analysis of the model showed significant enrichment in several tumor-relevant pathways and cellular protective biological processes. The expression of EPHB2, IL-13, MAP2, RPN2, and TRAF5 was correlated with microsatellite instability (MSI), while the expression of IL-13, RPN2, and TRAF5 was related to tumor mutation burden (TMB). GO analysis showed that the 11 target autophagy genes were chiefly enriched in mRNA processing, RNA splicing, and regulation of the mRNA metabolic process. KEGG analysis showed enrichment mainly in spliceosomes. We constructed a prognostic risk assessment model based on 11 autophagy-related genes in CRC.

Conclusion

A prognostic risk assessment model based on 11 autophagy-associated genes was constructed in CRC. The new model suggests directions and ideas for evaluating prognosis and provides guidance to choose better treatment strategies for CRC.

The synergistic antitumour effect of multi-components from Pulsatilla chinensis saponins in NCI-H460 lung cancer cell line through induction of apoptosis

Context: Pulsatilla chinensis (Bunge) Regel (Ranunculaceae) possess antitumour effects; however, its antitumour potential has not been extensively investigated.Objective: To investigate the synergetic effect of multi-components from P. chinensis induced cell apoptosis and explore the mechanism.Materials and methods: The cytotoxicity was measured against NCI-H460, SMMC-7721, HCT-116 and U251 cell lines treated with eight monomers from P. chinensis. The synergetic effect of a combination of Pulsatilla saponin D (PSD), Raddeanoside R13 (R13), and Pulsatilla saponin A (PSA) was assessed using CalcuSyn3.0. Annexin V-FITC/PI and DAPI staining analyzed apoptosis of NCI-H460 cells treated with PSD, R13 and PSA alone or in combination. Proteins differential expression was analyzed using proteomic, DAVID Bioinformatics Resources, R software environment and KEGG database, and verified by western blotting.Results: PSD, R13, and PSA displayed greater antitumor activity with IC₅₀ values of 5.6, 5.1 and 10.5 µM against NCI-H460 cells compared with other monomers. The combination of PSD, R13, and PSA had a synergistic effect at CI = 0.27 and induced 17.53% cells apoptotic detected by flow cytometric. Bioinformatic analysis showed an overview of the differentially expressed proteins and some signalling pathways. Moreover, some candidate proteins (LDHA, PI3K, NOL3 and cleaved-caspase-3) were validated by western blotting.Discussion and Conclusion: These results show PSD, R13, and PSA are good candidates as natural products for use in the treatment of lung cancer. Potential signalling pathways and protein targets need to be further validated. The application of the drug combination approach also provides a therapeutic strategy for cancer.

Proteomic analysis of human periodontal ligament cells under hypoxia

Background

The periodontal ligament is essential for homeostasis of periodontal tissue. A hypoxic milieu of the periodontal tissue is generated under periodontitis or during orthodontic treatment, which affects the periodontal and bone remodelling process. Here, we provide a comprehensive proteomic characterization of periodontal ligament cells under hypoxic conditions, aiming to reveal previously unappreciated biological changes and to help advance hypoxia-based therapeutic strategies for periodontal diseases.

Methods

Human periodontal ligament cells (hPDLCs) were characterized using immunohistochemistry (IHC) and flow cytometry (FACS). Successful hypoxia treatment of hPDLCs with 1% O₂ was confirmed by qRT-PCR. Proliferation was evaluated using an MTT assay. The proteomic expression profile under hypoxia was studied with the isobaric tags for relative and absolute quantification (iTRAQ) approach followed by protein identification and bioinformatic analysis, and western blot verification was performed.

Results

The hPDLCs were positive for vimentin, CD73 and CD105 and negative for keratin, CD34 and CD45. After hypoxia treatment, the mRNA expression of hypoxia-inducible factor 1a (HIF1a) was upregulated. The proliferation rate was elevated during the first 6 h but decreased from 6 h to 72 h. A total of 220 differentially expressed proteins were quantified in hPDLCs under hypoxia (1% O₂, 24 h), including 153 upregulated and 67 downregulated proteins, five of which were verified by western blot analysis. The Gene Ontology enriched terms included the energy metabolic process, membrane-bound organelle and vesicle, and protein binding terms. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated several involved pathways, including glycolysis/gluconeogenesis, biosynthesis of amino acids, the HIF-1 signalling pathway, and focal adhesion. A protein–protein interaction (PPI) network demonstrated the dominant role of autophagy over apoptosis under hypoxia.

Conclusion

The proteomic profile of hPDLCs under hypoxia was mainly related to energy metabolism, autophagy, and responses to stimuli such as adhesion and inflammation. Previously unrecognized proteins including solute carrier family proteins, heat shock proteins, ubiquitination-related enzymes, collagen and S100 family proteins are involved in adaptive response to hypoxia in hPDLCs and are thus of great research interest in future work.

Electronic supplementary material

The online version of this article (10.1186/s12953-019-0151-2) contains supplementary material, which is available to authorized users.

Stability towards the gastrointestinal simulated digestion and bioactivity of PAYCS and its digestive product PAY with cognitive improving properties

Pro-AlaTyr-Cys-Ser (PAYCS) was susceptible to digestion and its memory improving activity was linked to the activation of Nrf2/ARE and BDNF/CREB signaling.

Protein disulfide-isomerase A3 significantly reduces ischemia-induced damage by reducing oxidative and endoplasmic reticulum stress

Ischemia causes oxidative stress in the endoplasmic reticulum (ER), accelerates the accumulation of unfolded and misfolded proteins, and may ultimately lead to neuronal cell apoptosis. In the present study, we investigated the effects of protein disulfide-isomerase A3 (PDIA3), an ER-resident chaperone that catalyzes disulfide-bond formation in a subset of glycoproteins, against oxidative damage in the hypoxic HT22 cell line and against ischemic damage in the gerbil hippocampus. We also confirmed the neuroprotective effects of PDIA3 by using PDIA3-knockout HAP1 cells. The HT22 and HAP1 cell lines showed effective (dose-dependent and time-dependent) penetration and stable expression of the Tat-PDIA3 fusion protein 24 h after Tat-PDIA3 treatment compared to that in the control-PDIA3-treated group. We observed that the fluorescence for both 2',7'-dichlorofluorescein diacetate (DCF-DA) and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL), which are markers for the formation of hydrogen peroxide (H₂O₂)-induced reactive oxygen species and apoptosis, respectively, was higher in HAP1 cells than in HT22 cells. The administration of Tat-PDIA3 significantly reduced the (1) DCF-DA and TUNEL fluorescence in HT22 and HAP1 cells, (2) ischemia-induced hyperactivity that was observed 1 day after ischemia/reperfusion, (3) ischemia-induced neuronal damage and glial (astrocytes and microglia) activation that was observed in the hippocampal CA1 region 4 days after ischemia/reperfusion, and (4) lipid peroxidation and nitric oxide generation in the hippocampal homogenates 3-12 h after ischemia/reperfusion. Transient forebrain ischemia significantly elevated the immunoglobulin-binding protein (BiP) and C/EBP-homologous protein (CHOP) mRNA levels in the hippocampus at 12 h and 4 days after ischemia, relative to those in the time-matched sham-operated group. Administration of Tat-PDIA3 ameliorated the ischemia-induced upregulation of BiP mRNA levels versus the Tat peptide- or control-PDIA3-treated groups, and significantly reduced the induction of CHOP mRNA levels, at 12 h or 4 days after ischemia. Collectively, these results suggest that Tat-PDIA3 acts as a neuroprotective agent against ischemia by attenuating oxidative damage and blocking the apoptotic pathway that is related to the unfolded protein response in the ER.

Pharmacological Basis for the Use of Evodiamine in Alzheimer's Disease: Antioxidation and Antiapoptosis

Evodiamine (Evo), a major alkaloid compound isolated from the dry unripened fruit of Evodia fructus, has a wide range of pharmacological activities. The present study sought to explore the neuroprotective effects of Evo in l-glutamate (l-Glu)-induced apoptosis of HT22 cells, and in a d-galactose and aluminum trichloride-developed Alzheimer’s disease (AD) mouse model. Evo significantly enhanced cell viability, inhibited the accumulation of reactive oxygen species, ameliorated mitochondrial function, increased the B-cell lymphoma-2 protein content, and inhibited the high expression levels of Bax, Bad, and cleaved-caspase-3 and -8 in l-Glu-induced HT22 cells. Evo also enhanced the phosphorylation activities of protein kinase B and the mammalian target of rapamycin in the l-Glu-induced HT22 cells. In the AD mouse model, Evo reduced the aimless and chaotic movements, reduced the time spent in the central area in the open field test, and decreased the escape latency time in the Morris water maze test. Evo reduced the deposition of amyloid beta 42 (Aβ42) in the brain, and increased the serum level of Aβ42, but showed no significant effects on Aβ40. In addition, six weeks of Evo administration significantly suppressed oxidative stress by modulating the related enzyme levels. In the central cholinergic system of AD mice, Evo significantly increased the serum levels of acetylcholine and choline acetyltransferase and decreased the level of acetylcholinesterase in the serum, hypothalamus, and brain. Our results provide experimental evidence that Evo can serve as a neuroprotective candidate for the prevention and/or treatment of neurodegenerative diseases.

Myosin IIA-related Actomyosin Contractility Mediates Oxidative Stress-induced Neuronal Apoptosis

Oxidative stress-induced neuronal apoptosis plays an important role in the progression of central nervous system (CNS) diseases. In our study, when neuronal cells were exposed to hydrogen peroxide (H₂O₂), an exogenous oxidant, cell apoptosis was observed with typical morphological changes including membrane blebbing, neurite retraction and cell contraction. The actomyosin system is considered to be responsible for the morphological changes, but how exactly it regulates oxidative stress-induced neuronal apoptosis and the distinctive functions of different myosin II isoforms remain unclear. We demonstrate that myosin IIA was required for neuronal contraction, while myosin IIB was required for neuronal outgrowth in normal conditions. During H₂O₂-induced neuronal apoptosis, myosin IIA, rather than IIB, interacted with actin filaments to generate contractile forces that lead to morphological changes. Moreover, myosin IIA knockout using clustered regularly interspaced short palindromic repeats/CRISPR-associated protein-9 nuclease (CRISPR/Cas9) reduced H₂O₂-induced neuronal apoptosis and the associated morphological changes. We further demonstrate that caspase-3/Rho-associated kinase 1 (ROCK1) dependent phosphorylation of myosin light chain (MLC) was required for the formation of the myosin IIA-actin complex. Meanwhile, either inhibition of myosin II ATPase with blebbistatin or knockdown of myosin IIA with siRNA reversely attenuated caspase-3 activation, suggesting a positive feedback loop during oxidative stress-induced apoptosis. Based on our observation, myosin IIA-actin complex contributes to actomyosin contractility and is associated with the positive feedback loop of caspase-3/ROCK1/MLC pathway. This study unravels the biochemical and mechanistic mechanisms during oxidative stress-induced neuronal apoptosis and may be applicable for the development of therapies for CNS diseases.

The clinical utility of circulating neuroendocrine gene transcript analysis in well-differentiated paragangliomas and pheochromocytomas

CONTEXT

Paragangliomas and pheochromocytomas (PPGLs) exhibit variable malignancy, which is difficult to determine by histopathology, amine measurements or tissue genetic analyses.

OBJECTIVE

To evaluate whether a 51-neuroendocrine gene blood analysis has clinical utility as a diagnostic and prognostic marker.

DESIGN

Prospective cohort study. Well-differentiated PPGLs (n = 32), metastatic (n = 4); SDHx mutation (n = 25); 12 biochemically active, Lanreotide treated (n = 4). Nine patients had multiple sampling. Age- and gender-matched controls and GEP-NETs (comparators).

METHODS

Circulating neuroendocrine tumor mRNA measured (qPCR) with multianalyte algorithmic analysis. Metabolic, epigenomic and proliferative genes as well as somatostatin receptor expression were assessed (averaged, normalized gene expression: mean ± s.e.m.). Amines were measured by HPLC and chromogranin A by ELISA. Analyses (2-tailed): Fisher's test, non-parametric (Mann-Whitney), receiver-operator curve (ROC) and multivariate analysis (MVA). All data are presented as mean ± s.e.m.

RESULTS

PPGL were NETest positive (100%). All exhibited higher scores than controls (55 ± 5% vs 8 ± 1%, P = 0.0001), similar to GEP-NETs (47 ± 5%). ROC analysis area under curve was 0.98 for differentiating PPGLs/controls (cut-off for normal: 26.7%). Mutation status was not directly linked to NETest. Genetic and molecular clustering was associated (P < 0.04) with NETest scores. Metastatic (80 ± 9%) and multicentric (64 ± 9%) disease had significantly (P < 0.04) higher scores than localized disease (43 ± 7%). Progressive disease (PD) had the highest scores (86 ± 2%) vs stable (SD, 41 ± 2%) (P < 0.0001). The area under the curve for PD from SD was 0.93 (cut-off for PD: 53%). Proliferation, epigenetic and somatostatin receptor gene expression was elevated (P < 0.03) in PD. Metabolic gene expression was decreased in SDHx mutations. Repeat NETest measurements defined clinical status in the 9 patients (6 SD and 3 PD). Amine measurement was non-informative. Multivariate analysis identified NETest >53% as an independent prognostic factor.

CONCLUSION

Circulating NET transcript analysis is positive (100% diagnostic) in well-differentiated PCC/PGL, scores were elevated in progressive disease irrespective of mutation or biochemical activity and elevated levels were prognostic.