Tumor Necrosis Factor Alpha Induces Neural Stem Cell Apoptosis Through Activating p38 MAPK Pathway. Neurochem Res. 2016;41:3052-3062. [PMID: 27528245 DOI: 10.1007/s11064-016-2024-8]

Zearalenone (ZEN) impairs motor function and induces neurotoxicity via inflammatory pathways: Evidence from zebrafish models and molecular docking studies

ZEN is a low-molecular-weight food contaminant that is frequently detected in various crops and regions due to its high thermal stability and persistence. It poses a significant threat to the biological nervous system. However, the molecular mechanisms underlying ZEN-induced neurotoxicity remain incompletely understood. To further explore this issue, this study focused on the effects of ZEN on the nervous system, particularly its key targets and related molecular mechanisms. The study combined network toxicology and molecular docking methods and performed behavioral analysis of zebrafish larvae exposed to ZEN. Firstly, motor capacity tests revealed that ZEN exposure significantly reduced the overall movement speed of zebrafish larvae during both photoperiod and dark cycles. We then identified 141 potential targets associated with ZEN-induced neurotoxicity from the GeneCards, OMIM, and DrugBank databases. Further screening using STRING and Cytoscape software extracted 25 key nodes, including TP53, AKT1, CASP3, MAPK3, and NFKB1. Analysis of GO and KEGG pathways suggested 20 of the most relevant signaling pathways and indicated that the core targets of ZEN-induced neurotoxicity were primarily involved in inflammatory pathways. Molecular docking using AutoDock further confirmed the strong binding affinity between ZEN and the targets. All six core target proteins exhibited strong binding affinity with ZEN, with binding energies of less than -7. In summary, the results of this study suggest that ZEN may impact cognitive dysfunction and neuropathy by activating neuroinflammatory signaling pathways, ultimately leading to neuronal death. This study provides important insights into the molecular mechanisms of ZEN-induced neurotoxicity and highlights the potential for prevention and treatment of diseases associated with exposure to ZEN and similar food contaminants.

Acute COVID-19 and LongCOVID syndrome - molecular implications for therapeutic strategies - review

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has been recognized not only for its acute effects but also for its ability to cause LongCOVID Syndrome (LCS), a condition characterized by persistent symptoms affecting multiple organ systems. This review examines the molecular and immunological mechanisms underlying LCS, with a particular focus on autophagy inhibition, chronic inflammation, oxidative, nitrosative and calcium stress, viral persistence and autoimmunology. Potential pathophysiological mechanisms involved in LCS include (1) autoimmune activation, (2) latent viral persistence, where SARS-CoV-2 continues to influence host metabolism, (3) reactivation of latent pathogens such as Epstein-Barr virus (EBV) or cytomegalovirus (CMV), exacerbating immune and metabolic dysregulation, and (4) possible persistent metabolic and inflammatory dysregulation, where the body fails to restore post-infection homeostasis. The manipulation of cellular pathways by SARS-CoV-2 proteins is a critical aspect of the virus' ability to evade immune clearance and establish long-term dysfunction. Viral proteins such as NSP13, ORF3a and ORF8 have been shown to disrupt autophagy, thereby impairing viral clearance and promoting immune evasion. In addition, mitochondrial dysfunction, dysregulated calcium signaling, oxidative stress, chronic HIF-1α activation and Nrf2 inhibition create a self-sustaining inflammatory feedback loop that contributes to tissue damage and persistent symptoms. Therefore understanding the molecular basis of LCS is critical for the development of effective therapeutic strategies. Targeting autophagy and Nrf2 activation, glycolysis inhibition, and restoration calcium homeostasis may provide novel strategies to mitigate the long-term consequences of SARS-CoV-2 infection. Future research should focus on personalized therapeutic interventions based on the dominant molecular perturbations in individual patients.

Understanding chronic inflammation: couplings between cytokines, ROS, NO, Cai 2+, HIF-1α, Nrf2 and autophagy

Chronic inflammation is an important component of many diseases, including autoimmune diseases, intracellular infections, dysbiosis and degenerative diseases. An important element of this state is the mainly positive feedback between inflammatory cytokines, reactive oxygen species (ROS), nitric oxide (NO), increased intracellular calcium, hypoxia-inducible factor 1-alpha (HIF-1α) stabilisation and mitochondrial oxidative stress, which, under normal conditions, enhance the response against pathogens. Autophagy and the nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated antioxidant response are mainly negatively coupled with the above-mentioned elements to maintain the defence response at a level appropriate to the severity of the infection. The current review is the first attempt to build a multidimensional model of cellular self-regulation of chronic inflammation. It describes the feedbacks involved in the inflammatory response and explains the possible pathways by which inflammation becomes chronic. The multiplicity of positive feedbacks suggests that symptomatic treatment of chronic inflammation should focus on inhibiting multiple positive feedbacks to effectively suppress all dysregulated elements including inflammation, oxidative stress, calcium stress, mito-stress and other metabolic disturbances.

Parthenolide alleviates indomethacin-induced gastric ulcer in rats via antioxidant, anti-inflammatory, and antiapoptotic activities

Parthenolide (PTL) is a sesquiterpene lactone that occurs naturally. It demonstrates a variety of beneficial effects, such as antioxidant, anti-inflammatory, and antiapoptotic properties. The study investigated the potential protective impact of PTL on indomethacin (INDO) induced stomach ulcers in rats. The rats were classified into 5 distinct categories. Group 1 served as the "control" group. Rats in the second group received a single oral dosage of INDO (50 mg kg-1). Rats in Groups three and four received 20 and 40 mg kg-1 oral PTL 1 h before INDO. Omeprazole (30 mg kg-1) was given orally to Group 5 rats 1 h before INDO. Pretreatment with PTL increased stomach pH and decreased gastric volume as well as reduced the morphological and histological changes induced by INDO. Analysis of probable pathways showed that pre-treatment with PTL successfully reduced oxidative, inflammatory, and apoptotic consequences caused by INDO. The ingestion of PTL leads to a notable increase in the levels of glutathione reduced (GSH) and the activities of superoxide dismutase (SOD) and catalase (CAT). Furthermore, PTL decreased the concentration of malondialdehyde (MDA). In contrast, it was shown that PTL increased both cyclooxygenase-1 (COX-1) and prostaglandin E2 (PGE2). PTL shows a significant decrease in the expression of interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), inducible nitric oxide synthase (iNOS), and nuclear factor kappa B (NF-κB). PTL therapy resulted in a decrease in Bcl-2-associated X protein (Bax) levels and an increase in B-cell lymphoma 2 (Bcl2) levels. In conclusion, PTL offers gastroprotection by its antioxidant, anti-inflammatory, and anti-apoptotic qualities.

Cognitive Impairment Induced by Gestational Diabetes: The Role of Oxidative Stress

BACKGROUND

Cognitive impairment is defined as a neurological condition that alters multiple cerebral functions such as reasoning, memory, concentration, and association, among others. It has found to be widely correlated with several factors such as oxidative stress. The latter could be induced by numerous pathological conditions characterized by increased levels of free radicals and decreased levels of antioxidants. Pregnancy is a period when women undergo a physiological state of oxidative stress due to hormonal changes and increased oxygen requirements to maintain pregnancy. However, when oxidative stress exceeds antioxidant capacity, this leads to cellular damage that promotes a diabetogenic state. Recent studies suggest a possible association between gestational diabetes and cognitive impairment, but the underlying mechanisms remain unclear.

AIMS

We aim to explore the pathophysiological relationship between cognitive impairment and oxidative stress, focusing on the possible involvement of oxidative stress as the inducing mechanism.

METHODS

We performed a comprehensive literature review through PubMed and Google Scholar. Our keywords were "neuroinflammation", "cognitive impairment", "gestational diabetes", "oxidative stress", "antioxidants", and "free radicals".

RESULTS

From the initial 400 records identified, a total of 78 studies were analyzed and included in our study.

CONCLUSION

Oxidative stress plays a fundamental role in the development of cognitive impairment. Understanding this correlation is essential to the development of targeted medical interventions and, ultimately, promote research and prevention that will benefit the mother-child binomial in the short and long term.

Compensatory upregulation of MT2A alleviates neurogenic intermittent claudication through inhibiting activated p38 MAPK-mediated neuronal apoptosis

Neurogenic intermittent claudication (NIC), a classic symptom of lumbar spinal stenosis (LSS), is associated with neuronal apoptosis. To explore the novel therapeutic target of NIC treatment, we constructed the rat model of NIC by cauda equina compression (CEC) method and collected dorsal root ganglion (DRG) tissues, a region responsible for sensory and motor function, for mRNA sequencing. Bioinformatic analysis of mRNA sequencing indicated that upregulated metallothionein 2A (MT2A), an apoptosis-regulating gene belonging to the metallothionein family, might participate in NIC progression. Activated p38 MAPK mediated motor dysfunction following LSS and it was also found in DRG tissues of rats with NIC. Therefore, we supposed that MT2A might affect NIC progression by regulating p38 MAPK pathway. Then the rat model of NIC was used to explore the exact role of MT2A. Rats at day 7 post-CEC exhibited poorer motor function and had two-fold MT2A expression in DRG tissues compared with rats with sham operation. Co-localization analysis showed that MT2A was highly expressed in neurons, but not in microglia or astrocytes. Subsequently, neurons isolated from DRG tissues of rats were exposed to hypoxia condition (3% O2, 92% N2, 5% CO2) to induce cell damage. Gain of MT2A function in neurons was performed by lentivirus-mediated overexpression. MT2A overexpression inhibited apoptosis by inactivating p38 MAPK in hypoxia-exposed neurons. Our findings indicated that high MT2A expression was related to NIC progression, and MT2A overexpression protected against NIC through inhibiting activated p38 MAPK-mediated neuronal apoptosis in DRG tissues.

Function and Mechanism of Abscisic Acid on Microglia-Induced Neuroinflammation in Parkinson's Disease

Parkinson's disease (PD), as a neurologically implemented disease with complex etiological factors, has a complex and variable pathogenesis. Accompanying further research, neuroinflammation has been found to be one of the possible factors in its pathogenesis. Microglia, as intrinsic immune cells in the brain, play an important role in maintaining microenvironmental homeostasis in the brain. However, over-activation of neurotoxic microglia in PD promotes neuroinflammation, which further increases dopaminergic (DA) neuronal damage and exacerbates the disease process. Therefore, targeting and regulating the functional state of microglia is expected to be a potential avenue for PD treatment. In addition, plant extracts have shown great potential in the treatment of neurodegenerative disorders due to their abundant resources, mild effects, and the presence of multiple active ingredients. However, it is worth noting that some natural products have certain toxic side effects, so it is necessary to pay attention to distinguish medicinal ingredients and usage and dosage when using to avoid aggravating the progression of diseases. In this review, the roles of microglia with different functional states in PD and the related pathways inducing microglia to transform into neuroprotective states are described. At the same time, it is discussed that abscisic acid (ABA) may regulate the polarization of microglia by targeting them, promote their transformation into neuroprotective state, reduce the neuroinflammatory response in PD, and provide a new idea for the treatment of PD and the selection of drugs.

Dual-specificity phosphatase 1 inhibits Singapore grouper iridovirus replication via regulating apoptosis in Epinephelus coioides

The dual-specificity phosphatase (DUSP) family plays key roles in the maintenance of cellular homeostasis and apoptosis etc. In this study, the DUSP member DUSP1 of Epinephelus coioides was characterized: the length was 2371 bp including 281 bp 5' UTR, 911 bp 3' UTR, and a 1125 bp open reading frame encoding 374 amino acids. E. coioides DUSP1 has two conserved domains, a ROHD and DSPc along with a p38 MAPK phosphorylation site, localized at Ser308. E. coioides DUSP1 mRNA can be detected in all of the tissues examined, and the subcellular localization showed that DUSP1 was mainly distributed in the nucleus. Singapore grouper iridovirus (SGIV) infection could induce the differential expression of E. coioides DUSP1. Overexpression of DUSP1 could inhibit SGIV-induced cytopathic effect (CPE), the expressions of SGIV key genes, and the viral titers. Overexpression of DUSP1 could also regulate SGIV-induced apoptosis, and the expression of apoptosis-related factor caspase 3. The results would be helpful to further study the role of DUSP1 in viral infection.

Transplanting neurofibromatosis-1 gene knockout neural stem cells improve functional recovery in rats with spinal cord injury by enhancing the mTORC2 pathway

The poor survival and low efficiency of neuronal differentiation limits the therapeutic effects of transplanted neural stem cells in the treatment of spinal cord injury. Neurofibromatosis-1 (NF-1) is a tumor suppressor gene that restricts the rapid and abnormal growth and differentiation of neural cells. In the present study, lentiviral vectors were used to knock out NF-1, Ricotr (the core member of mTORC2) or NF-1+Ricotr in neural stem cells in vitro, and the NF-1, Ricotr or NF-1+Ricotr knockout neural stem cells were transplanted at the lesion site in a rat model of spinal cord injury (SCI). We first demonstrated that targeted knockout of NF-1 had an antiapoptotic effect and improved neuronal differentiation by enhancing the mTORC2/Rictor pathway of neural stem cells in vitro. Subsequently, transplanting NF-1 knockout neural stem cells into the injured site sufficiently promoted the tissue repair and functional recovery of rats with spinal cord injury by enhancing the survival and neuronal differentiation of grafted neural stem cells. Collectively, these findings reveal a prominent role of NF-1 in neural stem cell biology, which is an invaluable step forward in enhancing the benefit of neural stem cell-mediated regenerative cell therapy for spinal cord injury and identifies the transplantation of NF-1 knockout neural stem cells as a promising strategy for spinal cord injury.

Protective Effect of Anwulignan on Gastric Injury Induced by Indomethacin in Mice

Anwulignan (AN) is a monomer lignan from Schisandra sphenanthera Rehd. et Wits (Schisandra sphenanthera fructus, Schisandra sphenanthera). The protective effect of AN against the indomethacin (IND)-induced gastric injury to mice and the related mechanism of action was investigated in this study. The effect of AN was mainly assessed by observing the gastric tissue morphology, gastric ulcer index (GUI), ulcer inhibition rate (UIR), gastric juice volume (GJV) and pH value. Chemical colorimetry, immunofluorescence, ELISA, and Western blot were used to detect related factors in the gastric tissue. The results showed that AN reduced the GUI, increased the UIR, inhibited the GJV, and increased the gastric pH value. AN significantly increased cyclooxygenase-1, cyclooxygenase-2, and prostaglandin E2 expression levels in the gastric tissue, activated nuclear factor (erythroid-derived 2)-like 2 (Nrf2), increased heme oxygenase-1 expression, enhanced the activity of superoxide dismutase and glutathione peroxidase, and decreased the malondialdehyde content. AN reduced the phosphorylation of nuclear factor-κ gene binding (NF-κB) p65 and its nuclear translocation, the key protein of NF-κB signaling pathway in the gastric tissue, and the content of the pathway downstream signaling molecules, including interleukin-6, interleukin-1β, and tumor necrosis factor-α, to play an anti-inflammatory role. AN inhibited the downstream signals B-cell lymphoma 2-associated x protein and cleaved caspase-3 in gastric tissue, and activated B-cell lymphoma 2, to play an antiapoptotic role, which were further verified by Hoechst staining. Therefore, AN has a significant protection against the gastric injury induced by IND in mice, and the mechanism may be concerned in its activation of Nrf2, inhibition of NF-κB signaling pathway, and anti-apoptotic effect. SIGNIFICANCE STATEMENT: Anwulignan (AN) significantly reduced the indomethacin-induced gastric injury in mice, and its antioxidation, anti-inflammation, and antiapoptosis were considered to be involve in the effect, suggesting that AN should be a potential drug or food supplement for gastric injury induced by indomethacin.

Acute cytotoxicity test of PM2.5, NNK and BPDE in human normal bronchial epithelial cells: A comparison of a co-culture model containing macrophages and a mono-culture model

BACKGROUND

Based on extensive research on cytotoxicity of exogenous compounds in vitro, it is essential to develop a cell model that better mimics environment in vivo to explore cytotoxic mechanisms of exogenous compounds.

METHODS

A co-culture system was established using a transwell system with Beas-2B and U937 cells. Cells were treated with fine particulate matter (PM2.5; 25, 50 and 100 μg/mL), nicotine-derived nitrosamine ketone (NNK; 50, 100 and 200 μg/mL) and benzo(a)pyrene diol epoxide (BPDE; 0.5, 2 and 8 μM) for 24 h. Cell proliferation, apoptosis and cell cycle, DNA damage were detected by CCK-8 and EdU, flow cytometry, and comet assay, respectively. Differentially expressed transcript and cytokine concentrations were determined by transcriptome sequencing and Cytokine Array, respectively.

RESULTS

Compared with mono-culture, cell proliferation increased, apoptosis decreased, and DNA damage decreased in a dose-response relationship in co-culture. Gene expression profile was significantly different in co-culture, with significantly increased expression levels of 48 cytokines in co-culture.

CONCLUSION

Cytotoxic damage to Beas-2B cells induced by exogenous carcinogens, including PM2.5, NNK and BPDE, was significantly reduced in a co-culture system compared with a mono-culture system. The mechanism may be related to changes in expression of cytokines, such as LIF, and activation of related pathways, such as TNF signaling pathway. Cytotoxic damage to Beas-2B induced by PM2.5, NNK and BPDE, was significantly reduced in co-culture. The mechanism may be related to changes in expression of cytokines and activation of related pathways. These findings provide new insights into cytotoxicity and experimental basis for safety evaluations of exogenous carcinogens.

Targeting Programmed Cell Death to Improve Stem Cell Therapy: Implications for Treating Diabetes and Diabetes-Related Diseases

Stem cell therapies have shown promising therapeutic effects in restoring damaged tissue and promoting functional repair in a wide range of human diseases. Generations of insulin-producing cells and pancreatic progenitors from stem cells are potential therapeutic methods for treating diabetes and diabetes-related diseases. However, accumulated evidence has demonstrated that multiple types of programmed cell death (PCD) existed in stem cells post-transplantation and compromise their therapeutic efficiency, including apoptosis, autophagy, necroptosis, pyroptosis, and ferroptosis. Understanding the molecular mechanisms in PCD during stem cell transplantation and targeting cell death signaling pathways are vital to successful stem cell therapies. In this review, we highlight the research advances in PCD mechanisms that guide the development of multiple strategies to prevent the loss of stem cells and discuss promising implications for improving stem cell therapy in diabetes and diabetes-related diseases.

Web-based transcriptome analysis determines a sixteen-gene signature and associated drugs on hearing loss patients: A bioinformatics approach

Background

Hearing loss is becoming more and more general. It may occur at all age and affect the language learning ability of children and trigger serious social problems.

Methods

The hearing loss differentially expressed genes (HL‐DEGs) were recognized through a comparison with healthy subjects. The Gene Ontology (GO) analysis was executed by DAVID. The reactome analysis of HL‐DEGs was performed by Clue‐GO. Next, we used STRING, an online website, to identify crucial protein‐protein interactions among HL‐DEGs. Cytoscape software was employed to construct a protein‐protein interaction network. MCODE, a plug‐in of the Cytoscape software, was used for module analysis. Finally, we used DGIdb database to ascertain the targeted drugs for MCODE genes.

Results

Four hundred four HL‐DEGs were identified, among which the most up‐regulated 10 genes were AL008707.1, SDR42E1P5, BX005040.1, AL671883.2, MT1XP1, AC016957.1, U2AF1L5, XIST, DAAM2, and ADAMTS2, and the most down‐regulated 10 genes were ALOX15, PRSS33, IL5RA, SMPD3, IGHV1‐2, IGLV3‐9, RHOXF1P1, CACNG6, MYOM2, and RSAD2. Through STRING database and MCODE analysis, we finally got 16 MCODE genes. These genes can be regarded as hearing loss related genes. Through biological analysis, it is found that these genes are enriched in pathways related to apoptosis such as tumor necrosis factor. Among them, MMP8, LTF, ORM2, FOLR3, and TCN1 have corresponding targeted drugs. Foremost, MCODE genes should be investigated for its usefulness as a new biomarker for diagnosis and treatment.

Conclusion

In summary, our study produced a sixteen‐gene signature and associated drugs that could be diagnosis and treatment of hearing loss patients.

Blocking tumor necrosis factor-α delays progression of chronic obstructive pulmonary disease in rats through inhibiting MAPK signaling pathway and activating SOCS3/TRAF1

The present study was conducted in order to study the detailed molecular mechanism of tumor necrosis factor (TNF)-α in chronic obstructive pulmonary disease (COPD). The rats were treated with cigarette smoke (CS) and lipopolysaccharide (LPS) to establish the COPD model. Next, the changes in lung injury in COPD rats with TNF-α knockdown was tested. Meanwhile, the regulation of TNF-α on MAPK pathway and its downstream molecules (SOCS3/TRAF1) was determined by western blotting. On this basis, the activation of MAPK and inhibition of SOCS3/TRAF1 was also examined. Subsequently, the lung function was tested with the plethysmograph, the cells of bronchoalveolar lavage fluid was counted and classified. Furthermore, lung tissue sections were stained with hematoxylin and eosin to verify whether the treatment of MAPK pathway and downstream molecules affected the effect of TNF-α knockdown on COPD. The present study showed that TNF-α knockdown could alleviate the decrease in the function and inflammatory injury of the lungs of rats with COPD. Western blot analysis verified that TNF-α knockdown could inhibit the activation of MAPK pathway and increase the expression of SOCS3/TRAF1. The following experimental results showed that the relief of lung injury caused by TNF-α knockdown could be deteriorated by activating MAPK pathway. It was also found that the symptom of COPD was decreased following transfection with sh-TNF-α but worsened by SOCS3/TRAF1 knockdown. Overall, TNF-α knockdown inhibited the activation of MAPK pathway and increased the expression of SOCS3/TRAF1, thus delaying the process of COPD.

High Level of Inflammatory Cytokines in the Tears: A Bridge of Patients with Concomitant Exotropia and Dry Eye

Concomitant exotropia have obvious symptoms of eye discomfort in adults, and the presence of ocular surface inflammation in patients may be important mediators between concomitant exotropia and dry eye. Oculus Keratograph eye comprehensive analyzer was performed to detect noninvasive tear break time, noninvasive tear height, and eye red index, while the ocular surface disease index and schirmer I testing were made. The levels of IL-6, IL-10, IL-17A, IL-12P70, INF-γ, and TNF-α were detected in tears in patients with concomitant exotropia and healthy controls matched by age and gender through the Simoa technology. IL-6 was significantly higher in patients with concomitant exotropia (4.683 ± 1.329) pg/mL than that in normal group (1.455 ± 0.391) pg/mL, p = 0.0304. TNF-α was also significantly higher in patients (0.2095 ± 0.0703) pg/mL than normal group (0.0513 ± 0.0149) pg/mL, p = 0.0397. The levels of inflammatory factors in strabismic patients vs. normal controls were as follows: IL-17A (0.1551 pg/mL︰0.0793 pg/mL), IL-10 (0.3358 pg/mL︰0.0513 pg/mL), IL-12p70 (0.0253 pg/mL︰0.0099 pg/mL), and INF-γ (0.0284 pg/mL︰0.009 pg/mL) were detected, and the median of them in concomitant strabismus was 1.96-6.55-fold as much as the control group. High levels of inflammatory cytokines in tears of patients with concomitant exotropia, which may be a potentially factor promoted the occurrence of dry eye in the patients with concomitant exotropia.

Promising Intervention Approaches to Potentially Resolve Neuroinflammation And Steroid Hormones Alterations in Alzheimer's Disease and Its Neuropsychiatric Symptoms

Neuroinflammation is a biological process by which the central nervous system responds to stimuli/injuries affecting its homeostasis. So far as this reactive response becomes exacerbated and uncontrolled, it can lead to neurodegeneration, compromising the cognitive and neuropsychiatric domains. Parallelly, modifications in the hypothalamic signaling of neuroprotective hormones linked also to the inflammatory responses of microglia and astrocytes can exacerbate these processes. To complicate the picture, modulations in the gut microbiota (GM) can induce changes in neuroinflammation, altering cognitive and neuropsychiatric functioning. We conducted a web-based search on PubMed. We described studies regarding the cross-talk among microglia and astrocytes in the neuroinflammation processes, along with the role played by the steroid hormones, and how this can reflect on cognitive decline/neurodegeneration, in particular on Alzheimer's Disease (AD) and its neuropsychiatric manifestations. We propose and support the huge literature showing the potentiality of complementary/alternative therapeutic approaches (nutraceuticals) targeting the sustained inflammatory response, the dysregulation of hypothalamic system and the GM composition. NF-κB and Keap1/Nrf2 are the main molecular targets on which a list of nutraceuticals can modulate the altered processes. Since there are some limitations, we propose a new intervention natural treatment in terms of Oxygen-ozone (O2-O3) therapy that could be potentially used for AD pathology. Through a meta-analytic approach, we found a significant modulation of O3 on inflammation-NF-κB/NLRP3 inflammasome/Toll-Like Receptor 4 (TLR4)/Interleukin IL-17α signalling, reducing mRNA (p<0.00001 Odd Ratio (OR)=-5.25 95% CI:-7.04/-3.46) and protein (p<0.00001 OR=-4.85 95%CI:-6.89/-2.81) levels, as well as on Keap1/Nrf2 pathway. Through anti-inflammatory, immune, and steroid hormones modulation and anti-microbial activities, O3 at mild therapeutic concentrations potentiated with nutraceuticals and GM regulators could determine combinatorial effects impacting on cognitive and neurodegenerative domains, neuroinflammation and neuroendocrine signalling, directly or indirectly through the mediation of GM.

Programmed cell death in stem cell-based therapy: Mechanisms and clinical applications

Stem cell-based therapy raises hopes for a better approach to promoting tissue repair and functional recovery. However, transplanted stem cells show a high death percentage, creating challenges to successful transplantation and prognosis. Thus, it is necessary to investigate the mechanisms underlying stem cell death, such as apoptotic cascade activation, excessive autophagy, inflammatory response, reactive oxygen species, excitotoxicity, and ischemia/hypoxia. Targeting the molecular pathways involved may be an efficient strategy to enhance stem cell viability and maximize transplantation success. Notably, a more complex network of cell death receives more attention than one crucial pathway in determining stem cell fate, highlighting the challenges in exploring mechanisms and therapeutic targets. In this review, we focus on programmed cell death in transplanted stem cells. We also discuss some promising strategies and challenges in promoting survival for further study.

Neuroinflammatory processes are augmented in mice overexpressing human heat-shock protein B1 following ethanol-induced brain injury

Background

Heat-shock protein B1 (HSPB1) is among the most well-known and versatile member of the evolutionarily conserved family of small heat-shock proteins. It has been implicated to serve a neuroprotective role against various neurological disorders via its modulatory activity on inflammation, yet its exact role in neuroinflammation is poorly understood. In order to shed light on the exact mechanism of inflammation modulation by HSPB1, we investigated the effect of HSPB1 on neuroinflammatory processes in an in vivo and in vitro model of acute brain injury.

Methods

In this study, we used a transgenic mouse strain overexpressing the human HSPB1 protein. In the in vivo experiments, 7-day-old transgenic and wild-type mice were treated with ethanol. Apoptotic cells were detected using TUNEL assay. The mRNA and protein levels of cytokines and glial cell markers were examined using RT-PCR and immunohistochemistry in the brain. We also established primary neuronal, astrocyte, and microglial cultures which were subjected to cytokine and ethanol treatments. TNFα and hHSPB1 levels were measured from the supernates by ELISA, and intracellular hHSPB1 expression was analyzed using fluorescent immunohistochemistry.

Results

Following ethanol treatment, the brains of hHSPB1-overexpressing mice showed a significantly higher mRNA level of pro-inflammatory cytokines (Tnf, Il1b), microglia (Cd68, Arg1), and astrocyte (Gfap) markers compared to wild-type brains. Microglial activation, and 1 week later, reactive astrogliosis was higher in certain brain areas of ethanol-treated transgenic mice compared to those of wild-types. Despite the remarkably high expression of pro-apoptotic Tnf, hHSPB1-overexpressing mice did not exhibit higher level of apoptosis. Our data suggest that intracellular hHSPB1, showing the highest level in primary astrocytes, was responsible for the inflammation-regulating effects. Microglia cells were the main source of TNFα in our model. Microglia isolated from hHSPB1-overexpressing mice showed a significantly higher release of TNFα compared to wild-type cells under inflammatory conditions.

Conclusions

Our work provides novel in vivo evidence that hHSPB1 overexpression has a regulating effect on acute neuroinflammation by intensifying the expression of pro-inflammatory cytokines and enhancing glial cell activation, but not increasing neuronal apoptosis. These results suggest that hHSPB1 may play a complex role in the modulation of the ethanol-induced neuroinflammatory response.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-020-02070-2.

CD13: A Key Player in Multidrug Resistance in Cancer Chemotherapy

Cancer is one of the most serious diseases that are harmful to human health. Systemic chemotherapy is an optimal therapeutic strategy for the treatment of cancer, but great difficulty has been encountered in its administration in the form of multidrug resistance (MDR). As an enzyme on the outer cell surface, CD13 is documented to be involved in the MDR development of tumor cells. In this review, we will focus on the role of CD13 in MDR generation based on the current evidence.

New insights into the effects of caffeine on adult hippocampal neurogenesis in stressed mice: Inhibition of CORT-induced microglia activation

Chronic stress-evoked depression has been implied to associate with the decline of adult hippocampal neurogenesis. Caffeine has been known to combat stress-evoked depression. Herein, we aim to investigate whether the protective effect of caffeine on depression is related with improving adult hippocampus neurogenesis and explore the mechanisms. Mouse chronic water immersion restraint stress (CWIRS) model, corticosterone (CORT)-established cell stress model, a coculture system containing CORT-treated BV-2 cells and hippocampal neural stem cells (NSCs) were utilized. Results showed that CWIRS caused obvious depressive-like disorders, abnormal 5-HT signaling, and elevated-plasma CORT levels. Notably, microglia activation-evoked brain inflammation and inhibited neurogenesis were also observed in the hippocampus of stressed mice. In comparison, intragastric administration of caffeine (10 and 20 mg/kg, 28 days) significantly reverted CWIRS-induced depressive behaviors, neurogenesis recession and microglia activation in the hippocampus. Further evidences from both in vivo and in vitro mechanistic experiments demonstrated that caffeine treatment significantly suppressed microglia activation via the A2AR/MEK/ERK/NF-κB signaling pathway. The results suggested that CORT-induced microglia activation contributes to stress-mediated neurogenesis recession. The antidepression effect of caffeine was associated with unlocking microglia activation-induced neurogenesis inhibition.

Treatment with Minocycline Suppresses Microglia Activation and Reverses Neural Stem Cells Loss after Simulated Microgravity

The present study aimed to investigate the effect of microglia on simulated microgravity-induced hippocampal neurogenesis reduction and the possible mechanism underlying. Adult rats were treated with tail suspension for different times and the changes of neural stem cells (NSCs) were examined by immunohistochemistry. Then, minocycline was used to inhibit the activation of microglia, and the numbers of microglia and NSCs were detected after microgravity. Additionally, liquid protein chip analysis was applied to detect proinflammatory factors in hippocampus in order to find out the cytokines responsible for microglia activation after microgravity. The results revealed that microgravity increased the numbers of Iba1⁺ cells and decreased the numbers of BrdU⁺ and DCX⁺ cells in hippocampus but did not affect the ratio of NeuN⁺/BrdU⁺ cells to the total number of BrdU⁺ cells. After treated with minocycline, activated microglia were suppressed and the reduction of NSCs induced by microgravity recovered. Besides, compared with the control, higher concentrations of INF-γ and TNF-α were detected in the rats treated with microgravity. Our study provides the first evidence that microglia-mediated inflammation plays an important part in microgravity-induced neurogenesis reduction in hippocampus, and INF-γ and TNF-α secreted by microglia might be the key factors in this process.

Specific gene expression in type 1 diabetic patients with and without cardiac autonomic neuropathy

We hypothesized that some molecular pathways might interact to initiate the process of nervous tissue destruction, promoting cardiac autonomic neuropathy (CAN) in the course of diabetes type 1 (T1D). The study group consisted of 60 T1D patients (58.33% women/41.67% men), on standard therapy. The control group consisted of twenty healthy volunteers recruited in accordance with age, gender and body weight. The presence of CAN was documented by the Ewing test method (ProSciCard apparatus). A microarray data analysis was performed using Gene Spring version 13. The microarray results for selected genes were confirmed by real-time PCR (qRT-PCR), using specific TaqMan Gene Expression Assays. Plasma IL-6 content was measured by an enzyme-linked immunosorbent assay (ELISA). The p < 0.05 value was considered as statistically significant. The microarray analysis, confirmed by qRTPCR, showed significant up-regulation of autophagy, quantity of mitochondria, quality regulatory genes (mTOR, GABARAPL2) apoptosis, ER-stress and inflammation (NFKB1, IL1b, IL1R1, SOD1), in T1D when compared to the control group. A significantly higher IL-6 protein level was observed in T1D patients, in comparison to the control group. We concluded that the observed changes in gene expression and activation of intracellular pathways give a coherent picture of the important role of oxidative stress in inflammation and the activation of apoptosis in the pathomechanism of DM. The significance of the inflammatory process, confirmed by the increased level of the inflammation biomarker IL-6 in the pathomechanisms of CAN was shown even in patients with properly treated T1D.

Effects of Inhibition of miR-155-5p in Neural Stem Cell Subarachnoid Transplant on Rats with Cerebral Infarction

Cerebral infarction is a leading cause of death, which calls for effective prevention and treatment. Transplant of neural stem cells (NSCs) is a potential therapeutic treatment to cerebral infarction although its efficacy still needs to be improved. Overexpression of hypoxia-inducible factor 1α (HIF-1α) has been shown to enhance the protective effects of stem cell transplant on cerebral infarction. The expression of HIF-1α is predicted to be regulated by miR-155-5p. Therefore, we regulated the expression of miR-155-5p in NSCs and evaluated the effects of miR-155-5p-regulated NSC transplant on cerebral infarction. We inhibited miR-155-5p expression in NSCs by overexpressing miR-155-5p inhibitor. HIF-1α expression, cell viability, and the expression of apoptosis markers were examined. We established the middle cerebral artery occlusion (MCAO) rat model, and the infarct volume, neurobehavioral outcomes, inflammation, and oxidative stress were evaluated after NSC transplant. miR-155-5p directly targeted HIF-1α and negatively regulated its expression. Inhibition of miR-155-5p enhanced cell viability and prevented cell apoptosis. Transplant of miR-155-5p-inhibited NSCs significantly decreased infarct volume and improved neurobehavioral outcomes of MCAO rats. Transplant of miR-155-5p-inhibited NSCs significantly inhibited inflammation and oxidative stress. Inhibition of miR-155-5p in NSCs resulted in enhanced protection against cerebral infarction after NSC transplant.

Inhibition of livin overcomes radioresistance in nasopharyngeal carcinoma cells

BACKGROUND AND AIMS

Radiotherapy is one of the major remedies for the treatment of cancer, including nasopharyngeal carcinoma (NPC). Radioresistance occurs very often in target cells that is a large drawback in cancer treated with radiotherapy. Livin involves the over-growth of cancer cells. This study aims to investigate the role of livin in the radioresistance formation in NPC cells.

METHODS

NPC cell lines were exposed to small doses of irradiation to establish a cell model of radioresistance, in which the role of livin in the development of radioresistance was evaluated.

RESULTS

The expression of livin was observed in NPC cells, which was significantly increased after exposing to small doses of irradiation. A negative correlation was detected between livin and Fas expression in NPC cells. Livin formed a complex with heat shock factor-1 (HSF1, the transcription factor of Fas) in NPC cells after irradiation, which sped up ubiquitination of HSF1. Livin was involved in suppressing Fas expression in NPC cells with radioresistance. Exposure to livin inhibitors prevented radioresistance development and overcame the established radioresistance in NPC cells.

CONCLUSIONS

Livin expression in NPC cells plays a critical role in the development of radioresistance. Depletion of livin increases the sensitiveness of NPC cells to irradiation. Target therapy against livin may have the translational potential for the treatment of NPC.

Neurosteroids as regulators of neuroinflammation

Neuroinflammation is a physiological protective response in the context of infection and injury. However, neuroinflammation, especially if chronic, may also drive neurodegeneration. Neurodegenerative diseases, such as multiple sclerosis (MS), Alzheimer's disease (AD), Parkinson's disease (PD) and traumatic brain injury (TBI), display inflammatory activation of microglia and astrocytes. Intriguingly, the central nervous system (CNS) is a highly steroidogenic environment synthesizing steroids de novo, as well as metabolizing steroids deriving from the circulation. Neurosteroid synthesis can be substantially affected by neuroinflammation, while, in turn, several steroids, such as 17β-estradiol, dehydroepiandrosterone (DHEA) and allopregnanolone, can regulate neuroinflammatory responses. Here, we review the role of neurosteroids in neuroinflammation in the context of MS, AD, PD and TBI and describe underlying molecular mechanisms. Moreover, we introduce the concept that synthetic neurosteroid analogues could be potentially utilized for the treatment of neurodegenerative diseases in the future.

Hepatoprotective activity of raspberry ketone is mediated via inhibition of the NF-κB/TNF-α/caspase axis and mitochondrial apoptosis in chemically induced acute liver injury

Raspberry Ketone (RK) is a natural phenolic compound which is marketed nowadays as a popular weight-reducing remedy, with reported antioxidant and anti-inflammatory activities. However, its biological activity is not fully elucidated. Hepatotoxicity is the leading cause of acute liver failure in Europe and North America, and its management is still challenging. Therefore, this study aimed to assess the therapeutic detoxification activity of RK against liver injury in vivo and to explore the underlying mechanisms using carbon tetrachloride (CCl4)-induced hepatotoxicity as a model. First, a dose-response study using 4 different doses, 25, 50, 100, and 200 mg kg-1 day-1, of RK was conducted. RK was administered for 5 days as a pretreatment, followed by a single dose of CCl4 (1 ml kg-1, 1 : 1 v/v CCl4 : olive oil). The RK dose of 200 mg kg-1 showed the greatest protective effect and was selected for further investigations. CCl4 hepatotoxicity was confirmed by elevation of liver enzymes, and histopathological examination. CCl4-induced oxidative stress was evident from increased lipid peroxidation measured as thiobarbituric acid reactive substances (TBARS) along with depleted superoxide dismutase (SOD), reduced glutathione (GSH), and total antioxidant capacity (TAC). Increased oxidative stress was associated with increased cytochrome c expression with subsequent activation of caspase-9 and caspase-3, in addition to DNA fragmentation reflecting apoptosis. CCl4 also induced the expression of inflammatory cytokines (NF-κB and TNF-α). Interestingly, RK hepatoprotective activity was evident from the reduction of liver enzymes, and maintenance of hepatocyte integrity and microstructures as evaluated by histopathological examination using H and E, and transmission electron microscopy. The antioxidant activity of RK was demonstrated by the increase of TAC, SOD, and GSH, with a concomitant decrease of the TBARS level. Moreover, RK pretreatment inhibited CCl4-induced upregulation of inflammatory mediators. RK antiapoptotic activity was indicated by the reduction of the expression of cytoplasmic cytochrome-C, a decrease of caspases, and inhibition of DNA fragmentation. In conclusion, this study demonstrates that RK is a promising hepatoprotective agent. The underlying mechanisms include antioxidant, anti-inflammatory, and anti-apoptotic activities. This is the first study reporting RK hepatoprotective activity in acute hepatic injury and approves its antiapoptotic effect in the liver.

The implication of the crosstalk of Nrf2 with NOXs, and HMGB1 in ethanol-induced gastric ulcer: Potential protective effect is afforded by Raspberry Ketone

Ethanol consumption is one of the common causative agents implicated in gastric ulcer development. Oxidative stress plays a major role in the induction and development of gastric ulceration. NADPH oxidases (NOXs) and Nuclear factor erythroid 2-related factor 2 (Nrf2) are key players in ethanol-induced ulcers. High-mobility group box 1 (HMGB1), a ubiquitous nuclear protein, mediates various inflammation functions. However, the role of HMGB1 in ethanol-induced gastric ulcer is not yet elucidated. Raspberry Ketone (RK) is a natural phenolic compound with antioxidant and anti-inflammatory properties. In the present study, absolute ethanol (7.5 ml/kg) was used to induce gastric ulceration in rats. Raspberry Ketone (RK) (50 mg/kg) was given orally one hour before the administration of absolute ethanol. Interestingly, ethanol-induced gastric ulcer was associated with Nrf2 downregulation, which was correlated with NOX-1, 2 NOX-4, and HMGB1 upregulation, and was significantly reversed by RK pre-treatment. RK pre-treatment provided 80% gastroprotection. Gastroprotective properties of RK were mediated via antioxidant, anti-inflammatory (suppression of NF-kB and tumor necrosis factor-α), and antiapoptotic activities (reduction of Bax/Bcl2 ratio). Gastroprotective properties of RK were confirmed by histopathological examination. In conclusion, this study is the first to provide evidence to the role of HMGB1 in ethanol-induced gastric ulcer, and the crosstalk of Nrf2, NOXs and HMGB1. It also demonstrates that RK represents a promising gastroprotective activity comparable to omeprazole.

Cytotoxicity analysis of ambient fine particle in BEAS-2B cells on an air-liquid interface (ALI) microfluidics system

Ambient fine particle is a crucial indicator of air pollution brought into the air by sundry natural and public events. However, a comprehensive understanding of the PM_2.5-induced cytotoxicity especially the contribution of bioaerosol part is still undiscovered. Herein, an ALI microfluidics system integrated multi-omics (iTRAQ & RNA-seq) was successfully utilized to recognize the molecular mechanisms induced by microorganisms carried bioaerosol in human lung epithelial cells. The cells viability was above 98% within 21 days on this system. Moreover, the results showed that eight microorganisms-related pathways (e.g., Salmonella, amoebiasis, HTLV-1) were activated after exposure to PM_2.5 for 24 h, which played a certain proportion in contributing to inflammation reaction. In addition, multi-omics demonstrated that three inflammation-related signal transduction cascades including MAPK signaling pathway, TNF signaling pathway, and TGF signaling pathway were triggered by fine particles, ultimately leading to apoptosis-related process disorder by associated cytokines like TNF, IL6, and TGF-β. Furthermore, flow cytometry analysis showed that the cell apoptosis rate increased from 3.8% to 66.7% between the cells exposed to PM_2.5 (10 μg/cm²) for 24 h and untreated control cells, which indicated that the fine particles had the ability to activate apoptosis-related signal cascades and result in apoptosis. ELISA assay and western blot indicated that HO-1, JNK, IL6, TNF, NF-κB, and FGF14 were significantly increased after exposure to PM_2.5 while Casp3 and FGFR were decreased, which were consistent with the multi-omics. Moreover, PM_2.5 components (OC, EC, 16PAHs, As, Cu, Mn, Cl^-, and NO₃^-) were significantly correlated to the inflammation related proteins and cytokines, which played a vital role in the inflammation and apoptosis related signaling pathways. These findings pointed to strong links among microorganisms infection, inflammation, and apoptosis in cell response to PM_2.5 carried microorganisms. It also provided a new approach for understanding PM_2.5-induced cytotoxicity and health risks.

Understanding the Role of Antiviral Cytokines and Chemokines on Neural Stem/Progenitor Cell Activity and Survival

Viral infections of the central nervous system are accompanied by the expression of cytokines and chemokines that can be critical for the control of viral replication in the brain. The outcomes of cytokine/chemokine signaling in neural cells vary widely, with cell-specific effects on cellular activity, proliferation, and survival. Neural stem/progenitor cells (NSPCs) are often altered during viral infections, through direct infection by the virus or by the influence of immune cell activity or cytokine/chemokine signaling. However, it has been challenging to dissect the contribution of the virus and specific inflammatory mediators during an infection. In addition to initiating an antiviral program in infected NSPCs, cytokines/chemokines can induce multiple changes in NSPC behavior that can perturb NSPC numbers, differentiation into other neural cells, and migration to sites of injury, and ultimately brain development and repair. The focus of this review was to dissect the effects of common antiviral cytokines and chemokines on NSPC activity, and to consider the subsequent pathological consequences for the host from changes in NSPC function.

Investigation of candidate long noncoding RNAs and messenger RNAs in the immediate phase of spinal cord injury based on gene expression profiles

Spinal cord injury (SCI) is a serious devastating condition and it has a high mortality rate and morbidity rate. The early pathological changes in the immediate phase of SCI may play a major part in the development of secondary injury. Alterations in the expression of many long noncoding RNAs (lncRNAs) have been shown to play fundamental roles in the diseases of the central nervous system. However, the roles of lncRNAs and messenger RNAs (mRNAs) in the immediate phase of SCI are not clear. We examined the expression of mRNAs and lncRNAs in a rat model at 2 h after SCI and identified the differentially expressed lncRNAs (DE lncRNAs) and differentially expressed mRNAs (DE mRNAs) using microarray analysis. 772 DE lncRNAs and 992 DE mRNAs were identified in spinal cord samples in the immediate phase following SCI compared with control samples. Moreover, Gene Ontology (GO) term annotation results showed that CXCR chemokine receptor binding, neutrophil apoptotic process, neutrophil migration, neutrophil extravasation, macrophage differentiation, monocyte chemotaxis and cellular response to interleukin-1 (IL-1) were the main significantly enriched GO terms. The results of Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that the DEGs were enriched in toll-like receptor signaling pathway, p53 signaling pathway, MAPK signaling pathway and Jak-STAT signaling pathway. IL6, MBOAT4, FOS, TNF, JUN, STAT3, CSF2, MYC, CCL2 and FGF2 were the top 10 high-degree hub nodes and may be important targets in the immediate phase of SCI. The current study on provides novel insights into how lncRNAs and mRNAs regulate the pathogenesis of the immediate phase after SCI.

Electroacupuncture Restores Locomotor Functions After Mouse Spinal Cord Injury in Correlation With Reduction of PTEN and p53 Expression

Background: We previously showed that electroacupuncture (EA) at Jiaji points promotes expression of adhesion molecule L1 in spinal cord tissue after mouse spinal cord injury (SCI) and contributes to recovery of neural functions. Objective: We investigated the effects of EA on downstream signaling molecules of L1 and molecules relevant to apoptosis with the aim to understand the underlying molecular mechanisms. Methods: Female C57BL/6 mice were divided into a sham group, injury group, injury+acupuncture (AP) group and injury+EA group. We investigated the changes in cognate L1-triggered signaling molecules after SCI by immunofluorescence staining and immunoblot analysis. Results: Protein levels of phosphatase and tensin homolog (PTEN) and p53 were decreased by EA at different time points after injury, whereas the levels of phosphorylated mammalian target of rapamycin (pmTOR), p-Akt and phosphorylated extracellular signal-regulatedkinase (p-Erk) were increased. Also, levels of myelin basic protein (MBP) were increased by EA. AP alone showed less pronounced changes in expression of the investigated molecules, when compared to EA. Conclusion: We propose that EA contributes to neuroprotection by inhibiting PTEN and p53 expression and by increasing the levels of pmTOR/Akt/Erk and of MBP after SCI. These observations allow novel insights into the beneficial effects of EA via L1-triggered signaling molecules after injury.

Role of tumor necrosis factor-α in epithelial-to-mesenchymal transition in transplanted kidney cells in recipients with chronic allograft dysfunction

BACKGROUND

Chronic allograft dysfunction (CAD) is characterized by allograft kidney interstitial fibrosis, the underlying mechanism of which is unclear. Our aim was to elucidate the role and mechanism of TNF-α-induced epithelial-to-mesenchymal transition (EMT) in transplant kidney tubular interstitial fibrosis.

METHODS

Human kidney tissues from normal volunteers and CAD patients were assessed using periodic acid-Schiff, Masson trichrome and immunohistochemical staining. mRNA and protein expression of E-cadherin, α-smooth muscle actin (SMA) and fibronectin(FN) in renal proximal tubule epithelial (HK-2) cells after treatment with TNF-α under different conditions were assessed using western blot and qRT-PCR analysis. Cell motility and migration were assessed using wound healing and transwell assays. Expression of Smurf2 and TNF-α-signaling pathway-related proteins in HK-2 cells treated with TNF-α was detected by western blotting. E-cadherin and α-SMA expression was also assessed in Smurf2 plasmid-transfected or Smurf2 siRNA-treated HK-2 cells.

RESULTS

The expression of TNF-α, Smurf2, α-SMA, and fibronectin was significantly upregulated, while the expression of E-cad was downregulated in the CAD group compared with the normal group. The in vitro results showed that TNF-α remarkably upregulated the expression of Smurf2, α-SMA and fibronectin and downregulated the expression of E-cadherin in HK-2 cells and enhanced motility and migration in HK-2 cells. Overexpression of Smurf2 could promote the expression of α-SMA and inhibit the expression of E-cad, whereas knockdown of Smurf2 expression reversed TNF-α-induced upregulation of α-SMA and prohibited the reduction of E-cad expression. Furthermore, TNF-α-induced Smurf2 expression promoted EMT through the Akt signaling pathway.

CONCLUSIONS

TNF-α induced EMT via the TNF-α/Akt/Smurf2 signaling pathways, and it may play a role in aggravating allograft kidney interstitial fibrosis in CAD patients.

p38 Mitogen-Activated Protein Kinase is Involved in the Pathogenesis of Endometriosis by Modulating Inflammation, but not Cell Survival

BACKGROUND

Local pro-inflammatory environment and enhanced cell survival contribute to the endometriosis development. A serine/threonine kinase p38 mitogen-activated protein kinase (MAPK) mediates intracellular signaling of cytokine production, cell proliferation, and apoptosis in different cell types. The current study compares p38 MAPK activity in normal endometrium and endometriosis, and assesses role(s) of p38 MAPK on cytokine production and cell survival in endometriosis.

METHODS

Immunohistochemical levels of total and phosphorylated (active) p38 MAPK as well as its correlation with interleukin 8 (IL-8) expression, and cell proliferation and apoptosis were compared in normal human endometrium and endometriosis. The action of p38 MAPK on pro-inflammatory cytokine-induced IL-8 and monocyte chemotactic protein (MCP)-1 expression in endometriotic cells were assessed by enzyme-linked immunosorbent assay. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide cell survival, 5-bromo-2'-deoxyuridine incorporation, and Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling assays were used to determine the function of p38 MAPK in cultured human endometriotic stromal cell proliferation and apoptosis.

RESULTS

p38 MAPK activity was significantly higher in both eutopic and ectopic endometria compared to normal endometria during late proliferative and early secretory phases ( P < .05). Increased p38 MAPK activity in endometriotic cells correlated with IL-8 expression (Pearson correlation coefficient r = 0.83, P < .01), but not with apoptosis in vivo. The pro-inflammatory cytokines IL-1β and tumor necrosis factor (TNF)-α induced activation of p38 MAPK. Inhibition of p38 MAPK activity blocked IL-1β and TNF-α-induced IL-8 and MCP-1 secretion in cultured endometriotic stromal cells ( P < .05), but did not impact on endometriotic cell survival.

CONCLUSIONS

These results suggest that rather than modulating cell survival, increased p38 MAPK activity in endometriotic cells contributes to the pathogenesis of endometriosis by promoting the local inflammatory milieu.

Vitamin C mitigates oxidative/nitrosative stress and inflammation in doxorubicin-induced cardiomyopathy

Increase in oxidative/nitrosative stress is one of the mechanisms associated with the development of cardiotoxicity due to doxorubicin (Dox), a potent chemotherapy drug. Previously, we reported mitigation of Dox-induced oxidative/nitrosative stress and apoptosis by vitamin C (Vit C) in isolated cardiomyocytes. In the present in vivo study in rats, we investigated the effect of prophylactic treatment with Vit C on Dox-induced apoptosis, inflammation, oxidative/nitrosative stress, cardiac dysfunction, and Vit C transporter proteins. Dox (cumulative dose: 15 mg/kg) in rats reduced systolic and diastolic cardiac function and caused structural damage. These changes were associated with a myocardial increase in reactive oxygen species, reduction in antioxidant enzyme activities, increased expression of apoptotic proteins, and inflammation. Dox also caused an increase in the expression of proapoptotic proteins Bax, Bnip-3, Bak, and caspase-3. An increase in oxidative/nitrosative stress attributable to Dox was indicated by an increase in superoxide, protein carbonyl formation, lipid peroxidation, nitric oxide (NO), NO synthase (NOS) activity, protein nitrosylation, and inducible NOS protein expression. Dox increased the levels of cardiac proinflammatory cytokines TNF-α, IL-1β, and IL-6, whereas the expression of Vit C transporter proteins (sodium-ascorbate cotransporter 2 and glucose transporter 4) was reduced. Prophylactic and concurrent treatment with Vit C prevented all these changes and improved survival in the Vit C + Dox group. Vit C also improved Dox-mediated systolic and diastolic dysfunctions and structural damage. These results suggest a cardioprotective role of Vit C in Dox-induced cardiomyopathy by reducing oxidative/nitrosative stress, inflammation, and apoptosis, as well as improving Vit C transporter proteins.NEW & NOTEWORTHY This in vivo study provides novel data that vitamin C improves cardiac structure and function in doxorubicin-induced cardiomyopathy by reducing oxidative/nitrosative stress, apoptosis, and inflammation along with upregulation of cardiac vitamin C transporter proteins. The latter may have a crucial role in improving antioxidant status in this cardiomyopathy.

TGF-β1 protects intestinal integrity and influences Smads and MAPK signal pathways in IPEC-J2 after TNF-α challenge

The aim of this study was to investigate the protective effects of TGF-β1 on intestinal epithelial barrier, as well as canonical Smad and MAPK signal pathways involved in these protection processes by a IPEC-J2 model stimulated with TNF-α. IPEC-J2 monolayers were treated without or with TNF-α in the absence or presence of TGF-β1. The results showed that TGF-β1 pretreatment ameliorated TNF-α-induced intestinal epithelial barrier disturbances as indicated by decrease of transepithelial electrical resistance (TER) and increase of paracellular permeability. TGF-β1 also dramatically alleviated TNF-α-induced alteration of TJ proteins ZO-1 and occludin. Moreover, TGF-β1 pretreatment increased TβRII protein expression in IPEC-J2 monolayers challenged with TNF-α. In addition, a significant increase of Smad4 and Smad7 mRNA was also observed in the TGF-β1 pretreatment after TNF-α challenge compared with the control group. Furthermore, TGF-β1 pretreatment enhanced smad2 protein activation. These results indicated that the canonical Smad signaling pathway was activated by TGF-β1 pretreatment. Finally, TGF-β1 pretreatment decreased the ratios of the phosphorylated to total JNK and p38 (p-JNK/JNK and p-p38/p38) and increased the ratio of ERK (p-ERK/ERK). Anti-TGF-β1 Abs reduced these TGF-β1 effects. These results indicated that TGF-β1 protects intestinal integrity and influences Smad and MAPK signal pathways in IPEC-J2 after TNF-α challenge.