Reactive oxygen species are downstream products of TRAF-mediated signal transduction

Fig Meal Replacement Powder Ameliorates Obesity, Oxidative Stress and Intestinal Microbiota in Mice Fed With High-Fat Diet

Figs, known for their high-antioxidant capacity, have shown potential in regulating obesity. However, research on fig-based products and the mechanisms behind their effects remains limited. This study aims to systematically evaluate the potential of fig meal replacement powder (FMRP) in regulating obesity and mitigating obesity-induced oxidative stress through both in vitro and in vivo experiments, while also elucidating its underlying mechanisms. The results demonstrated that FMRP exhibited superior nutritional value and antioxidant activity compared to commercially available alternatives. Furthermore, FMRP significantly reduced weight gain, improved lipid metabolism, alleviated liver damage and oxidative stress, and positively modulated the gut microbiota in high-fat diet (HFD)-fed mice. Gut microbiota analysis showed that FMRP could restore the gut microbiota of hfd mice. For instance, it reduced the Firmicutes/Bacteroidetes (F/B) ratio. The correlation analysis has revealed the key bacterial genera related to obesity and oxidative stress. The key bacterial genera related to obesity include Desulfovibrio, Lachnoclostridium, etc., while the key bacterial genera related to oxidative stress include Bifidobacterium, Lactobacillus, and Turicibacter, etc. In conclusion, FMRP effectively alleviates oxidative stress, improves lipid metabolism, and modulates the gut microbiota, highlighting its potential as a functional food for obesity management.

Genetic interaction between oxidative stress and body mass index in a Spanish population

Oxidative stress may act as a contributing factor in the development of an elevated body mass index (BMI). Oxidative stress has the potential to modulate genetic activity at various levels, including gene transcription and protein function regulation. Nevertheless, the interplay between genetic variants and oxidative stress in relation to BMI remains to be elucidated. Based on this premise, we studied the potential association between 723 single-nucleotide polymorphisms (SNPs) located within a set of 212 genes and both BMI and oxidative stress parameters in 1502 adults from the general Spanish population (Hortega Study). Oxidative stress parameters measured included malondialdehyde (MDA) levels, 8-oxo-2'-deoxyguanosine (8-oxo-dG) levels and oxidised/reduced glutathione ratio (GSSG/GSH). We also examined the potential impact of the interaction between these SNPs and oxidative stress levels on BMI. The genes selected regulate several key biological processes, including obesity, blood pressure, inflammation, lipid metabolism and redox homeostasis. Our findings indicate a robust association between specific genes and both BMI and oxidative stress parameters. Significant BMI-related interactions between genes and oxidative stress parameters were identified, which have a multifactorial impact on oxidative stress modulation and on BMI. SNPs identified in genes such as NPPA, CPT1A, DDIT3, NOX and IL6ST were significantly associated with all oxidative stress parameters analysed, indicating a substantial influence on BMI modulation. The results provide compelling evidence of a significant relationship between oxidative stress levels and genetic background. Our data provide new insights into BMI modulation by oxidative stress levels, highlighting a role for TNF as a key player in the interrelation of oxidative stress and BMI.

Molecular mechanisms behind the inhibitory effects of ginsenoside Rg3 on hepatic fibrosis: a review

Hepatitis is a chronic inflammatory liver disease and an important cause of liver fibrosis, which can progress to cirrhosis and even hepatocellular carcinoma if left untreated. However, liver fibrosis is a reversible disease, so finding new intervention targets and molecular markers is the key to preventing and treating liver fibrosis. Ginseng, the roots of Panax ginseng C. A. Meyer, is a precious Traditional Chinese Medicines with high medicinal value and is known as the "king of all herbs", and its active ingredient, ginsenoside Rg3 is a rare saponin and a new class of drug, one of the most thoroughly and extensively studied in a large number of studies. Ginsenoside Rg3 is an active ingredient extracted from ginseng that possesses a variety of biological activities, including anti-inflammatory, antioxidant, and anti-fibrotic effects. Several studies have suggested that ginsenoside Rg3 may help reduce hepatic inflammation and oxidative stress, thereby slowing the progression of liver fibrosis. Ginsenoside Rg3 may have some therapeutic effects on liver fibrosis, and the underlying molecular mechanisms behind these effects are attributed to cellular autophagy, apoptosis, and anti-inflammation, as well as the modulation of antioxidant activity and multiple signaling pathways. The molecular mechanisms behind the inhibitory effect of ginsenoside Rg3 on hepatic fibrosis are reviewed, with a view to providing reference for related studies.

Building a Bridge Between the Mechanism of EBV Reactivation and the Treatment of EBV-Associated Cancers

Epstein-Barr virus (EBV) infection is closely associated with the development of various tumors such as lymphomas and epithelial cancers. EBV has a discrete life cycle with latency and lytic phases. In recent years, significant progress has been made in the understanding of the mechanism underlying the transition of EBV from latency to lytic replication. Multiple new lytic activation factors have been emerged and promoted our understanding of this field. In addition, we have comprehensively presented the existing therapeutic strategies and their relationship to the mechanism underlying the transition of EBV from latency to lytic replication in this review, such as lytic induction therapy and drugs to prevent EBV from entering the lytic phase fully utilize the EBV reactivation mechanisms. This year marks the 60th anniversary of the discovery of EBV, and building a bridge between the mechanism of EBV reactivation and the treatment may help us to design new approaches for treating EBV-associated diseases.

Impairment of Renal and Hematopoietic Stem/Progenitor Cell Compartments in Frailty Syndrome: Link With Oxidative Stress, Plasma Cytokine Profiles, and Nuclear DNA Damage

Frailty is an age-related syndrome that drives multiple physiological system impairments in some older adults, and its pathophysiological mechanisms remain unclear. We evaluated whether frailty-related biological processes could impair stem cell compartments, specifically the renal stem compartment, given that kidney dysfunctions are frequent in frailty. A well-characterized in vitro nephrosphere model of human adult renal stem/progenitor cells has been instrumental to and was appropriate for verifying this hypothesis in our current research. Evaluating the effects of plasma from older individuals with frailty (frail plasma) on allogeneic renal stem/progenitor cells, we showed significant functional impairment and nuclear DNA damage in the treated cells of the renal stem compartment. The analysis of the frail plasma revealed mitochondrial functional impairment associated with the activation of oxidative stress and a unique inflammatory mediator profile in frail individuals. In addition, the plasma of frail subjects also contained the highest percentage of DNA-damaged autologous circulating hematopoietic progenitor/stem cells. The integration of both molecular and functional data obtained allowed us to discern patterns associated with frailty status, irrespective of the comorbidities present in the frail individuals. The data obtained converged toward biological conditions that in frailty caused renal and hematopoietic impairment of stem cells, highlighting the possibility of concomitant exhaustion of several stem compartments.

Reactive oxygen species in endothelial signaling in COVID-19: Protective role of the novel peptide PIP-2

INTRODUCTION

Recent research suggests that endothelial activation plays a role in coronavirus disease 2019 (COVID-19) pathogenesis by promoting a pro-inflammatory state. However, the mechanism by which the endothelium is activated in COVID-19 remains unclear.

OBJECTIVE

To investigate the mechanism by which COVID-19 activates the pulmonary endothelium and drives pro-inflammatory phenotypes.

HYPOTHESIS

The "inflammatory load or burden" (cytokine storm) of the systemic circulation activates endothelial NADPH oxidase 2 (NOX2) which leads to the production of reactive oxygen species (ROS) by the pulmonary endothelium. Endothelial ROS subsequently activates pro-inflammatory pathways.

METHODS

The inflammatory burden of COVID-19 on the endothelial network, was recreated in vitro, by exposing human pulmonary microvascular endothelial cells (HPMVEC) to media supplemented with serum from COVID-19 affected individuals (sera were acquired from patients with COVID-19 infection that eventually died. Sera was isolated from blood collected at admission to the Intensive Care Unit of the Hospital of the University of Pennsylvania). Endothelial activation, inflammation and cell death were assessed in HPMVEC treated with serum either from patients with COVID-19 or from healthy individuals. Activation was monitored by measuring NOX2 activation (Rac1 translocation) and ROS production; inflammation (or appearance of a pro-inflammatory phenotype) was monitored by measuring the induction of moieties such as intercellular adhesion molecule (ICAM-1), P-selectin and the NLRP3 inflammasome; cell death was measured via SYTOX™ Green assays.

RESULTS

Endothelial activation (i.e., NOX2 activation and subsequent ROS production) and cell death were significantly higher in the COVID-19 model than in healthy samples. When HPMVEC were pre-treated with the novel peptide PIP-2, which blocks NOX2 activation (via inhibition of Ca2+-independent phospholipase A2, aiPLA2), significant abrogation of ROS was observed. Endothelial inflammation and cell death were also significantly blunted.

CONCLUSIONS

The endothelium is activated during COVID-19 via cytokine storm-driven NOX2-ROS activation, which causes a pro-inflammatory phenotype. The concept of endothelial NOX2-ROS production as a unifying pathophysiological axis in COVID-19 raises the possibility of using PIP-2 to maintain vascular health.

TRAF2 inhibits senescence in hepatocellular carcinoma cells via regulating the ROMO1/ NAD+/SIRT3/SOD2 axis

The suppression of tumor proliferation via cellular senescence has emerged as a promising approach for anti-tumor therapy. Tumor necrosis factor receptor-associated factor 2 (TRAF2), an adaptor protein involved in the NF-κB signaling pathway and reactive oxygen species (ROS) production, has been implicated in hepatocellular carcinoma (HCC) proliferation. However, little is currently known about whether TRAF2 promotes HCC development by inhibiting cellular senescence. Replicative senescence model and IR-induced mouse model demonstrated that TRAF2 expression was decrease in senescence cells or liver tissues. Depletion of TRAF2 could inhibit proliferation and arrest the cell cycle via activating p53/p21WAF1 and p16INK4a/pRb signaling pathways in HCC cells and eventually lead to cellular senescence. Mechanistically, TRAF2 deficiency increased the expression of mitochondrial protein reactive oxygen species modulator 1 (ROMO1) and subsequently activated the NAD+/SIRT3/SOD2 pathway to promote the production of ROS and cause mitochondrial dysfunction, which eventually contributed to DNA damage response (DDR). Our findings demonstrate that TRAF2 deficiency inhibits the proliferation of HCC by promoting senescence. Therefore, targeting TRAF2 through various approaches holds therapeutic potential for treating HCC.

Mitochondrial Regulation of Macrophages in Innate Immunity and Diverse Roles of Macrophages During Cochlear Inflammation

Macrophages are essential components of the innate immune system and constitute a non-specific first line of host defense against pathogens and inflammation. Mitochondria regulate macrophage activation and innate immune responses in various inflammatory diseases, including cochlear inflammation. The distribution, number, and morphological characteristics of cochlear macrophages change significantly across different inner ear regions under various pathological conditions, including noise exposure, ototoxicity, and age-related degeneration. However, the exact mechanism underlying the role of mitochondria in macrophages in auditory function remains unclear. Here, we summarize the major factors and mitochondrial signaling pathways (e.g., metabolism, mitochondrial reactive oxygen species, mitochondrial DNA, and the inflammasome) that influence macrophage activation in the innate immune response. In particular, we focus on the properties of cochlear macrophages, activated signaling pathways, and the secretion of inflammatory cytokines after acoustic injury. We hope this review will provide new perspectives and a basis for future research on cochlear inflammation.

Molecular mechanisms of resveratrol as chemo and radiosensitizer in cancer

One of the primary diseases that cause death worldwide is cancer. Cancer cells can be intrinsically resistant or acquire resistance to therapies and drugs used for cancer treatment through multiple mechanisms of action that favor cell survival and proliferation, becoming one of the leading causes of treatment failure against cancer. A promising strategy to overcome chemoresistance and radioresistance is the co-administration of anticancer agents and natural compounds with anticancer properties, such as the polyphenolic compound resveratrol (RSV). RSV has been reported to be able to sensitize cancer cells to chemotherapeutic agents and radiotherapy, promoting cancer cell death. This review describes the reported molecular mechanisms by which RSV sensitizes tumor cells to radiotherapy and chemotherapy treatment.

Respiratory issues in patients with multiple sclerosis as a risk factor during SARS-CoV-2 infection: a potential role for exercise

Coronavirus disease-2019 (COVID-19) is associated with cytokine storm and is characterized by acute respiratory distress syndrome (ARDS) and pneumonia problems. The respiratory system is a place of inappropriate activation of the immune system in people with multiple sclerosis (MS), and this may cause damage to the lung and worsen both MS and infections.The concerns for patients with multiple sclerosis are because of an enhance risk of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The MS patients pose challenges in this pandemic situation, because of the regulatory defect of autoreactivity of the immune system and neurological and respiratory tract symptoms. In this review, we first indicate respiratory issues associated with both diseases. Then, the main mechanisms inducing lung damages and also impairing the respiratory muscles in individuals with both diseases is discussed. At the end, the leading role of physical exercise on mitigating respiratory issues inducing mechanisms is meticulously evaluated.

Unlocking the power of NOX2: A comprehensive review on its role in immune regulation

Reactive oxygen species (ROS) are a family of highly reactive molecules with numerous, often pleiotropic functions within the cell and the organism. Due to their potential to destroy biological structures such as membranes, enzymes and organelles, ROS have long been recognized as harmful yet unavoidable by-products of cellular metabolism leading to "oxidative stress" unless counterbalanced by cellular anti-oxidative defense mechanisms. Phagocytes utilize this destructive potential of ROS released in high amounts to defend against invading pathogens. In contrast, a regulated and fine-tuned release of "signaling ROS" (sROS) provides essential intracellular second messengers to modulate central aspects of immunity, including antigen presentation, activation of antigen presenting cells (APC) as well as the APC:T cell interaction during T cell activation. This regulated release of sROS is foremost attributed to the specialized enzyme NADPH-oxidase (NOX) 2 expressed mainly in myeloid cells such as neutrophils, macrophages and dendritic cells (DC). NOX-2-derived sROS are primarily involved in immune regulation and mediate protection against autoimmunity as well as maintenance of self-tolerance. Consequently, deficiencies in NOX2 not only result in primary immune-deficiencies such as Chronic Granulomatous Disease (CGD) but also lead to auto-inflammatory diseases and autoimmunity. A comprehensive understanding of NOX2 activation and regulation will be key for successful pharmaceutical interventions of such ROS-related diseases in the future. In this review, we summarize recent progress regarding immune regulation by NOX2-derived ROS and the consequences of its deregulation on the development of immune disorders.

CD30 induces Reed-Sternberg cell-like morphology and chromosomal instability in classic Hodgkin lymphoma cell lines

Classic Hodgkin lymphoma (cHL) is characterized by multinucleated cells called Reed-Sternberg (RS) cells and genetic complexity. Although CD30 also characterizes cHL cells, its biological roles are not fully understood. In this report, we examined the link between CD30 and these characteristics of cHL cells. CD30 stimulation increased multinucleated cells resembling RS cells. We found chromatin bridges, a cause of mitotic errors, among the nuclei of multinucleated cells. CD30 stimulation induced DNA double-strand breaks (DSBs) and chromosomal imbalances. RNA sequencing showed significant changes in the gene expression by CD30 stimulation. We found that CD30 stimulation increased intracellular reactive oxygen species (ROS), which induced DSBs and multinucleated cells with chromatin bridges. The PI3K pathway was responsible for CD30-mediated generation of multinucleated cells by ROS. These results suggest that CD30 involves generation of RS cell-like multinucleated cells and chromosomal instability through induction of DSBs by ROS, which subsequently induces chromatin bridges and mitotic error. The results link CD30 not only to the morphological features of cHL cells, but also to the genetic complexity, both of which are characteristic of cHL cells.

CD30 stimulation induces multinucleation and chromosomal instability in HTLV-1-infected cell lines

A recent report indicated involvement of CD30 in progression of human leukemia virus type 1 (HTLV-1) infection, but the exact roles of CD30 in this process remain unclear. This study was conducted to determine the role of CD30 by stimulating CD30 expressed on HTLV-1-infected cell lines with CD30 ligand and observing its effects. CD30 stimulation increased multinucleated cells and inhibited proliferation of HTLV-1-infected cells. This inhibition was recovered by interruption of CD30 stimulation. Chromatin bridges found in multinucleated cells suggested DNA damage. CD30 stimulation triggered DNA double-strand breaks (DSBs) and chromosomal imbalances. CD30 stimulation induced reactive oxygen species (ROS), which induced DSBs. Generation of ROS and multinucleated cells by CD30 was dependent on phosphoinositide 3-kinase. RNA sequencing showed that CD30 stimulation produced significant changes in gene expression profiles, including upregulation of programmed death ligand 1 (PD-L1). Tax, which has also been shown to induce multinucleation and chromosomal instability, failed to induce CD30. These results suggest that induction of CD30, independent of Tax, triggers morphological abnormalities, chromosomal instability, and alteration of gene expression in HTLV-1-infected cells.

Mitochondrial Metabolism in Pancreatic Ductal Adenocarcinoma: From Mechanism-Based Perspectives to Therapy

Pancreatic ductal adenocarcinoma (PDAC), the fourteenth most common malignancy, is a major contributor to cancer-related death with the utmost case fatality rate among all malignancies. Functional mitochondria, regardless of their complex ecosystem relative to normal cells, are essential in PDAC progression. Tumor cells' potential to produce ATP as energy, despite retaining the redox potential optimum, and allocating materials for biosynthetic activities that are crucial for cell growth, survival, and proliferation, are assisted by mitochondria. The polyclonal tumor cells with different metabolic profiles may add to carcinogenesis through inter-metabolic coupling. Cancer cells frequently possess alterations in the mitochondrial genome, although they do not hinder metabolism; alternatively, they change bioenergetics. This can further impart retrograde signaling, educate cell signaling, epigenetic modifications, chromatin structures, and transcription machinery, and ultimately satisfy cancer cellular and nuclear demands. To maximize the tumor microenvironment (TME), tumor cells remodel nearby stromal cells and extracellular matrix. These changes initiate polyclonality, which is crucial for growth, stress response, and metastasis. Here, we evaluate all the intrinsic and extrinsic pathways drawn by mitochondria in carcinogenesis, emphasizing the perspectives of mitochondrial metabolism in PDAC progression and treatment.

The oncogenic driving force of CD30 signaling-induced chromosomal instability in adult T-cell leukemia/lymphoma

Adult T-cell leukemia/lymphoma (ATL) develops via stepwise accumulation of gene mutations and chromosome aberrations. However, the molecular mechanisms underlying this tumorigenic process are poorly understood. We previously reported the presence of a biological link between the expression of CD30, which serves as a marker for ATL progression, and the actively proliferating fraction of human T-cell leukemia virus type 1 (HTLV-1)-infected cells that display polylobulation. Here, we demonstrated that CD30 signaling induced chromosomal instability with clonal expansion through DNA double-strand breaks (DSBs) via an increase of intracellular reactive oxygen species. CD30⁺ ATL cells were composed of subclones with additional genomic aberrations compared with CD30^- ATL cells in ATL patients. Furthermore, we found an accumulation of copy number loss of DSB repair-related genes as the disease progressed. Taken together, CD30 expression on ATL cells appears to be correlated with genomic instability, suggesting that CD30 signaling is one of the oncogenic factors of ATL progression with clonal evolution. This study provides new insight into the biological roles of CD30 signaling and could improve our understanding of tumorigenic processes of HTLV-1-infected cells.

Volatile organic compounds: A proinflammatory activator in autoimmune diseases

The etiopathogenesis of inflammatory and autoimmune diseases, including pulmonary disease, atherosclerosis, and rheumatoid arthritis, has been linked to human exposure to volatile organic compounds (VOC) present in the environment. Chronic inflammation due to immune breakdown and malfunctioning of the immune system has been projected to play a major role in the initiation and progression of autoimmune disorders. Macrophages, major phagocytes involved in the regulation of chronic inflammation, are a major target of VOC. Excessive and prolonged activation of immune cells (T and B lymphocytes) and overexpression of the master pro-inflammatory constituents [cytokine and tumor necrosis factor-alpha, together with other mediators (interleukin-6, interleukin-1, and interferon-gamma)] have been shown to play a central role in the pathogenesis of autoimmune inflammatory responses. The function and efficiency of the immune system resulting in immunostimulation and immunosuppression are a result of exogenous and endogenous factors. An autoimmune disorder is a by-product of the overproduction of these inflammatory mediators. Additionally, an excess of these toxicants helps in promoting autoimmunity through alterations in DNA methylation in CD4 T cells. The purpose of this review is to shed light on the possible role of VOC exposure in the onset and progression of autoimmune diseases.

MicroRNA-124 attenuates PTSD-like behaviors and reduces the level of inflammatory cytokines by downregulating the expression of TRAF6 in the hippocampus of rats following single-prolonged stress

BACKGROUND

MicroRNA-124-3p (miR-124) plays an important role in neuroprotective functions in various neurological disorders, but whether miR-124 participates in the pathological progression of posttraumatic stress disorder (PTSD) remains poorly understood.

METHODS

In the present study, we assessed the level of neuroinflammation in the hippocampus of rats exposed to single-prolonged stress (SPS) by Western blot and immunofluorescence staining, while the effect of miR-124 on PTSD-like behaviors was evaluated by behavioral test.

RESULTS

Our results showed that the level of miR-124 in the hippocampus of rats exposed to SPS was downregulated and that the upregulation of miR-124 could alleviate the PTSD-like behaviors of SPS rats. This effect of miR-124 might be achieved through TNF receptor-associated Factor 6 (TRAF6), which is a target gene of miR-124 and plays an important role in the immune and inflammatory reaction by regulating nuclear factor kappa-B (NF-κB). Furthermore, we found that miR-124 not only decreased the level of proinflammatory cytokines but also increased the expression levels of synaptic proteins (PSD95 and synapsin I) and regulated the morphology of neurons.

CONCLUSION

These results suggested that miR-124 might attenuate PTSD-like behaviors and decrease the level of proinflammatory cytokines by downregulating the expression of TRAF6 in the hippocampus of rats exposed to SPS.

ROS/TNF-α Crosstalk Triggers the Expression of IL-8 and MCP-1 in Human Monocytic THP-1 Cells via the NF-κB and ERK1/2 Mediated Signaling

IL-8/MCP-1 act as neutrophil/monocyte chemoattractants, respectively. Oxidative stress emerges as a key player in the pathophysiology of obesity. However, it remains unclear whether the TNF-α/oxidative stress interplay can trigger IL-8/MCP-1 expression and, if so, by which mechanism(s). IL-8/MCP-1 adipose expression was detected in lean, overweight, and obese individuals, 15 each, using immunohistochemistry. To detect the role of reactive oxygen species (ROS)/TNF-α synergy as a chemokine driver, THP-1 cells were stimulated with TNF-α, with/without H2O2 or hypoxia. Target gene expression was measured by qRT-PCR, proteins by flow cytometry/confocal microscopy, ROS by DCFH-DA assay, and signaling pathways by immunoblotting. IL-8/MCP-1 adipose expression was significantly higher in obese/overweight. Furthermore, IL-8/MCP-1 mRNA/protein was amplified in monocytic cells following stimulation with TNF-α in the presence of H2O2 or hypoxia (p ˂ 0.0001). Synergistic chemokine upregulation was related to the ROS levels, while pre-treatments with NAC suppressed this chemokine elevation (p ≤ 0.01). The ROS/TNF-α crosstalk involved upregulation of CHOP, ERN1, HIF1A, and NF-κB/ERK-1,2 mediated signaling. In conclusion, IL-8/MCP-1 adipose expression is elevated in obesity. Mechanistically, ROS/TNF-α crosstalk may drive expression of these chemokines in monocytic cells by inducing ER stress, HIF1A stabilization, and signaling via NF-κB/ERK-1,2. NAC had inhibitory effect on oxidative stress-driven IL-8/MCP-1 expression, which may have therapeutic significance regarding meta-inflammation.

Raising the 'Good' Oxidants for Immune Protection

Redox medicine is a new therapeutic concept targeting reactive oxygen species (ROS) and secondary reaction products for health benefit. The concomitant function of ROS as intracellular second messengers and extracellular mediators governing physiological redox signaling, and as damaging radicals instigating or perpetuating various pathophysiological conditions will require selective strategies for therapeutic intervention. In addition, the reactivity and quantity of the oxidant species generated, its source and cellular location in a defined disease context need to be considered to achieve the desired outcome. In inflammatory diseases associated with oxidative damage and tissue injury, ROS source specific inhibitors may provide more benefit than generalized removal of ROS. Contemporary approaches in immunity will also include the preservation or even elevation of certain oxygen metabolites to restore or improve ROS driven physiological functions including more effective redox signaling and cell-microenvironment communication, and to induce mucosal barrier integrity, eubiosis and repair processes. Increasing oxidants by host-directed immunomodulation or by exogenous supplementation seems especially promising for improving host defense. Here, we summarize examples of beneficial ROS in immune homeostasis, infection, and acute inflammatory disease, and address emerging therapeutic strategies for ROS augmentation to induce and strengthen protective host immunity.

Clinical and genetic characterization of PYROXD1-related myopathy patients from Turkey

Congenital myopathies (CMs) are a heterogeneous group of inherited muscle disorders characterized by muscle weakness at birth, while limb-girdle muscular dystrophies (LGMD) have a later onset and slower disease progression. Thus, detailed clinical phenotyping of genetically defined disease entities are required for the full understanding of genotype-phenotype correlations. A recently defined myopathic genetic disease entity is caused by bi-allelic variants in a gene coding for pyridine nucleotide-disulfide oxidoreductase domain 1 (PYROXD1) with unknown substrates. Here, we present three patients from two consanguineous Turkish families with mild LGMD, facial weakness, normal CK levels, and slow progress. Genomic analyses revealed a homozygous known pathogenic missense variant (c.464A>G, p.Asn155Ser) in family 1 with two affected females. In the affected male of family 2, we found this variant in a compound heterozygous state together with a novel frameshift variant (c.329_332delTCTG, p.Leu112Valfs*8), which is the second frameshift variant known so far in PYROXD1. We have been able to define a large homozygous region in family 1 sharing a common haplotype with family 2 in the critical region. Our data suggest that c.464A>G is a Turkish founder mutation. To gain deeper insights, we performed a systematic review of all published PYROXD1-related myopathy cases. Our analysis showed that the c.464A > G variant was found in 87% (20/23) of the patients and that it may cause either a childhood- or adult-onset phenotype, irrespective of its presence in a homozygous or compound heterozygous state. Interestingly, only four patients had elevated CK levels (up to 1000 U/L), and cardiac involvement was found in few compound heterozygous cases.

The Role of Mitochondria in Immune-Cell-Mediated Tissue Regeneration and Ageing

During tissue injury events, the innate immune system responds immediately to alarms sent from the injured cells, and the adaptive immune system subsequently joins in the inflammatory reaction. The control mechanism of each immune reaction relies on the orchestration of different types of T cells and the activators, antigen-presenting cells, co-stimulatory molecules, and cytokines. Mitochondria are an intracellular signaling organelle and energy plant, which supply the energy requirement of the immune system and maintain the system activation with the production of reactive oxygen species (ROS). Extracellular mitochondria can elicit regenerative effects or serve as an activator of the immune cells to eliminate the damaged cells. Recent clarification of the cytosolic escape of mitochondrial DNA triggering innate immunity underscores the pivotal role of mitochondria in inflammation-related diseases. Human mesenchymal stem cells could transfer mitochondria through nanotubular structures to defective mitochondrial DNA cells. In recent years, mitochondrial therapy has shown promise in treating heart ischemic events, Parkinson's disease, and fulminating hepatitis. Taken together, these results emphasize the emerging role of mitochondria in immune-cell-mediated tissue regeneration and ageing.

Pro-apoptotic functions of TRAF2 in p53-mediated apoptosis induced by cisplatin

Tumor necrosis factor receptor-associated factor 2 (TRAF2) is an essential component of tumor necrosis factor-α (TNF-α) signaling that regulates nuclear factor-κB (NF-κB) and c-Jun N-terminal kinase (JNK) pathways, and compelling evidence has demonstrated that TRAF2 suppresses TNF-α-induced cytotoxicity. On the other hand, it has been reported that oxidative stress-induced cytotoxicity is potentiated by TRAF2, indicating that TRAF2 both positively and negatively regulates stress-induced cytotoxicity in a context-specific manner. However, the causal role of TRAF2 in DNA damage response (DDR) remains to be explored. In this study, we assessed the function of TRAF2 in DDR induced by cisplatin, a representative DNA-damaging agent, and found that TRAF2 exerts pro-apoptotic activity through p53-dependent mechanisms at least in human fibrosarcoma cell line HT1080. TRAF2 deficient cells exhibit significant resistance to cell death induced by cisplatin, accompanied by the reduction of both p53 protein level and caspase-3 activation. Moreover, cisplatin-induced JNK activation was attenuated in TRAF2-deficient cells, and pharmacological inhibition of JNK signaling suppressed p53 stabilization. These results suggest that TRAF2 promotes p53-dependent apoptosis by activating the JNK signaling cascade in HT1080 cells. Thus, our data demonstrate a novel function of TRAF2 in cisplatin-induced DDR as a pro-apoptotic protein.

The relationship between TRAF6 and tumors

Tumor necrosis factor receptor (TNFR)-related factors (TRAFs) are important linker molecules in the tumor necrosis factor superfamily (TNFSF) and the Toll-like/interleukin-1 receptor (TLR/ILR) superfamily. There are seven members: TRAF1-TRAF7, among those members, tumor necrosis factor receptor-associated factor 6 (TRAF6) is upregulated in various tumors, which has been related to tumorigenesis and development. With the in-depth study of the relationship between TRAF6 and different types of tumors, TRAF6 has oncogenic characteristics involved in tumorigenesis, tumor development, invasion, and metastasis through various signaling pathways, therefore, targeting TRAF6 has provided a novel strategy for tumor treatment. This review summarizes and analyzes the role of TRAF6 in tumorigenesis and tumor development in combination with the current research on TRAF6 and tumors.

The Effect of Rice Bran Extract on Arterial Blood Pressure, Hepatic Steatosis, and Inflammation in Mice Fed with a High-Fat Diet

Background

Inflammation and hypertension are primary mechanisms involving in obesity-associated adverse effects of a high-fat diet. The aim of this study was to evaluate the effects of rice bran extract (RBE) on arterial blood pressure, hepatic steatosis, inflammation, and oxidative stress in high-fat diet (HFD)-induced obese mice.

Methods

Male ICR mice were divided into four groups, including a normal-diet control group, a high-fat diet (HFD) (60% kcal from fat) group, an HFD group treated with RBE (220 mg/kg/day), and an HFD group treated with 1100 mg/kg/day for eight weeks. Besides body weight and arterial blood pressure, we determined liver values of total cholesterol, triglyceride, as well as percent body fat, tumor necrosis factor-α (TNF-α), malondialdehyde (MDA), nuclear factor kappa-B (NF-κB), matrix metalloprotease-9 (MMP-9), cyclooxygenase-2 (COX-2), and mRNA endothelial nitric oxide synthase (eNOS).

Results

The HFD group had increased body weight, increased systolic and diastolic blood pressure, liver total cholesterol, triglyceride, NF-κB, COX-2 and MMP-9 protein levels, and decreased mRNA eNOS in the aorta. Mice of the HFD group receiving RBE had reduced diastolic blood pressure, as well as significantly decreased liver and serum TNF-α and MDA levels in the liver, and reduced NF-κB levels in both the liver and heart.

Conclusions

These results demonstrate that RBE decreases diastolic blood pressure, the liver lipid droplet accumulation, liver and myocardial NF-κB, myocardial COX-2 and MMP-9 protein levels, and oxidative stress. Moreover, RBE may improve endothelial function and may alleviate adverse health effects associated with obesity including obesity-associated hypertension.

EDA2R mediates podocyte injury in high glucose milieu

EDA2R is a member of the large family of tumor necrosis factor receptor (TNFR). Previous studies suggested that EDA2R expression might be increased in the kidneys of diabetic mice. However, its mRNA and protein expression in kidneys were not analyzed; moreover, its role in the development of diabetic kidney disease was not explored. Here we analyzed the mRNA and protein expressions of EDA2R in diabetic kidneys and examined its role in the podocyte injury in high glucose milieu. By analysis with real-time PCR, Western blotting, we found that both the mRNA and protein levels of EDA2R were increased in the kidneys of diabetic mice. Immunohistochemical studies revealed that EDA2R expression was enhanced in both glomerular and tubular cells of diabetic mice and humans. In vitro studies, high glucose increased EDA2R expression in cultured human podocytes. Overexpression of EDA2R in podocytes promoted podocyte apoptosis and decreased nephrin expression. Moreover, ED2AR increased ROS generation in podocytes, while inhibiting ROS generation attenuates EDA2R-mediated podocyte injury. In addition, EDA2R silencing partially suppressed high glucose-induced ROS generation, apoptosis, and nephrin decrease. Our study demonstrated that high glucose increases EDA2R expression in kidney cells and that EDA2R induces podocyte apoptosis and dedifferentiation in high glucose milieu partially through enhanced ROS generation.

Blue Mussel (Mytilus edulis) Water Extract Ameliorates Inflammatory Responses and Oxidative Stress on Osteoarthritis in Obese Rats

Purpose

To investigate the effects of Mytilus edulis water extract (MWE) on an anterior cruciate ligament transection and a partial medial meniscectomy surgery to induced osteoarthritis (OA) with the high-fat diet (HFD)-induced obese rats.

Methods

The male Sprague-Dawley rats were fed with HFD for 4 weeks before surgery. The OA rats were orally administered with MWE (108.5, 217.0, and 542.5 mg/kg) for 6 weeks.

Results

The administration of MWE affected weight loss, triglycerides content, and total cholesterol level. MWE also enhanced the activity of superoxide dismutase and decreased lipid peroxidation degree. Moreover, MWE reduced proinflammatory cytokines level, alleviated inflammation and swelling of the osteoarthritic knee, and reduced loss of proteoglycan in articular cartilage tissue.

Conclusion

MWE suppressed proinflammatory mediators and attenuated the cartilage degradation and pain in osteoarthritis rats under obesity condition. Therefore, MWE has the potential to act as an alternative for osteoarthritis treatment.

Nephroprotective effect of ferulic acid on gentamicin-induced nephrotoxicity in female rats

Ferulic acid is a kind of phenolic compound that can be found in various fruits and vegetables. This study aims to investigate the effect of ferulic acid on nephrotoxicity induced by gentamicin (GM). In this study, rats were separated into 4 groups such that each containing 8 randomly selected rats: Control group, Ferulic Acid (FA) group, Gentamicin (GM) group and Gentamicin + Ferulic acid (GM + FA) group. Blood samples were collected after 24 hours following the 8-day trial period, and kidneys were taken out for histopathological evaluation. Serum urea, creatinine, uric acid and LDH analyses were performed in autoanalyzer while Malondialdehyde (MDA), Advanced Oxidized Protein Products (AOPP), Glutathione (GSH), Superoxide dismutase (SOD), Catalase (CAT), Interleukin 6 (IL-6), Tumor Necrosis Factor-alpha (TNF-α) analyses were performed in ELISA, and kidney tissues were also examined histopathologically. Urea (p < .001), creatinine (p < .001), MDA (p < .01), AOPP (p < .001), IL-6 (p < .01) and TNF-α (p < .001) levels were found to be statistically and significantly lowered in GM + FA group when compared to GM group. As a result, ferulic acid has reduced the inflammation in nephrotoxicity induced by GM, causing decreased oxidative stress. In this study, anti-inflammatory features of ferulic acid have come to the forefront rather than the antioxidant features. It can be said that ferulic acid reduces nephrotoxic damage and has protective properties for kidneys.

Cardiovascular Changes Related to Metabolic Syndrome: Evidence in Obese Zucker Rats

Metabolic syndrome (MetS) is a predictor of cardiovascular diseases, commonly associated with oxidative stress and inflammation. However, the pathogenic mechanisms are not yet fully elucidated. The aim of the study is to evaluate the oxidative status and inflammation in the heart of obese Zucker rats (OZRs) and lean Zucker rats (LZRs) at different ages. Morphological and morphometric analyses were performed in the heart. To study the oxidative status, the malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), protein oxidation, and antioxidant enzymes were measured in plasma and heart. To elucidate the inflammatory markers involved, immunohistochemistry and Western blot were performed for cellular adhesion molecules and proinflammatory cytokines. OZRs were characterized by hypertension, hyperlipidemia, hyperglycemia, and insulin resistance. The obesity increased MDA and decreased the activities of superoxide dismutase (SOD) in plasma as well as in the heart, associated with cardiomyocytes hypertrophy. OxyBlot in plasma and in heart showed an increase of oxidativestate proteins in OZRs. Vascular cell adhesion molecule-1, interleukin-6, and tumor necrosis factor-α expressions in OZRs were higher than those of LZRs. However, these processes did not induce apoptosis or necrosis of cardiomyocytes. Thus, MetS induces the lipid peroxidation and decreased antioxidant defense that leads to heart tissue changes and coronary inflammation.

Vitellaria paradoxa Nut Triterpene-Rich Extract Ameliorates Symptoms of Inflammation on Post-Traumatic Osteoarthritis in Obese Rats

Purpose

To investigate the ameliorative effects of Vitellaria paradoxa (VP) nut extract for an anterior cruciate ligament transection with medial meniscectomy (ACLT+MMx)-induced osteoarthritis (OA) in high-fat diet (HFD)-induced obese rats.

Methods

The rats were fed by HFD for 5 weeks before surgery-induced OA. Rats were treated orally with three different doses of VP nut extract (111.6, 223.2, and 446.4 mg/kg) for 8 weeks.

Results

The VP nut triterpene-rich extract decreased the level of triglycerides and increased high-density lipoprotein-cholesterol. The level of nitric oxide, interleukin (IL)-1β, IL-6, and tumor necrosis factor-α decreased after treatment with VP nut triterpene-rich extract, especially in high-doses. The VP nut triterpene-rich extracts also alleviated swelling in the knee OA, weight-bearing difference, and suppressed cartilage degradation.

Conclusion

The Vitellaria paradoxa nut triterpene-rich extract suppressed proinflammatory mediators and attenuated the cartilage degradation and pain in osteoarthritis with an obesity rat model. As such, Vitellaria paradoxa nut triterpene-rich extract can be used as an alternative for osteoarthritis treatment.

Albumin-impregnated bone granules modulate the interactions between mesenchymal stem cells and monocytes under in vitro inflammatory conditions

Bone regeneration around newly implanted biomaterials is a complex process, which in its early phases involves the interactions between Mesenchymal Stem Cells (MSCs) and immune cells. The response of these cells to the biomaterial depends both on the local microenvironment and on the characteristics of the inserted bone substitute. In this work, bone allografts impregnated with albumin are loaded with a co-culture of human MSCs and monocytes; bone granules without albumin are used for comparison. Co-cultures are contextually treated with pro-inflammatory cytokines to simulate the inflammatory milieu naturally present during the bone regeneration process. As revealed by microscopic images, albumin-impregnated bone granules promote adhesion and interactions between cells populations. Compared to control granules, albumin coating diminishes reactive species production by cells. This reduced oxidative stress may be attributable to antioxidant properties of albumin, and it is also reflected in the mitigated gene expression of mitochondrial electron transport chain complexes, where most intracellular reactive molecules are generated. MSCs-monocytes co-cultured onto albumin-impregnated bone granules additionally release higher amounts of immunomodulatory cytokines and growth factors. In summary, this work demonstrates that impregnation of bone granules with albumin positively modulates the interactions between MSCs and immune cells, consequently influencing their mutual activities and immunomodulatory functions.

The Tangled Mitochondrial Metabolism in Cancer: An Innovative Pharmacological Approach

BACKGROUND

Mitochondria are remarkably gaining significant and different pathogenic roles in cancer (i.e., to sustain specific metabolism, to activate signaling pathways, to promote apoptosis resistance, to favor cancer cell dissemination, and finally to facilitate genome instability). Interestingly, all these roles seem to be linked to the fundamental activity of mitochondria, i.e. oxidative metabolism. Intriguingly, a typical modification of mitochondrial oxidative metabolism and reactive oxygen species production/ neutralization seems to have a central role in all these tangled pathogenic roles in cancer. On these bases, a careful understanding of the molecular relationships between cancer and mitochondria may represent a fundamental step to realize therapeutic approaches blocking the typical cancer progression. The main aim of this review is to stress some neglected aspects of oxidative mitochondrial metabolism of cancer cells to promote more translational research with diagnostic and therapeutic potential.

METHODS

We reviewed the available literature regarding clinical and experimental studies on various roles of mitochondria in cancer, with attention to the cancer cell mitochondrial metabolism.

RESULTS

Mitochondria are an important source of reactive oxygen species. Their toxic effects seem to increase in cancer cells. However, it is not clear if damage depends on ROS overproduction and/or defect in detoxification. Failure of both these processes is likely a critical component of the cancer process and is strictly related to the actual microenvironment of cancer cells.

CONCLUSIONS

Mitochondria, also by ROS production, have a fundamental pathogenetic role in promoting and maintaining cancer and its spreading. To carefully understand the tangled redox state of cancer cells mitochondria represents a fundamental step to realize therapeutic approaches blocking the typical cancer progression.

Pyridine nucleotide-disulphide oxidoreductase domain 2 (PYROXD2): Role in mitochondrial function

Pyridine Nucleotide-Disulphide Oxidoreductase Domain 2 (PYROXD2), a Hepatitis B virus X protein (HBx)-interacting protein, is significantly down-regulated in hepatocellular carcinoma (HCC), however its exact biological function remains unclear. The aim of this study is to investigate the subcellular localization and biological function of PYROXD2 in hepatic cells. The results showed that PYROXD2 was imported to the mitochondrial inner membrane/matrix by Tom40 and Tim23, but not Mia40. PYROXD2 151-230aa might be the mitochondrial targeting sequence. PYROXD2 interacted with complex IV subunit COX5B. Knockout of PYROXD2 decreased MMP, intracellular ROS, complex IV activity, cell proliferation, ATP content and mtDNA copy number, but increased mtROS levels and the number of immature mitochondria. In summary, our data illustrated that PYROXD2 localizes to the mitochondrial inner membrane/matrix, and it plays important roles in regulating mitochondrial function.

Impaired skin barrier function caused by reactive oxygen species in mice with colonic tumours

Purpose: We have previously reported that skin barrier function is disrupted in mice with colonic tumours induced by azoxymethane (AOM) and dextran sodium sulphate (DSS). We postulated that the impaired skin barrier function was associated with reactive oxygen species derived from gp91phox. In this study, we investigated the mechanisms underlying the impaired skin barrier function using gp91phox-/- mice. Materials and methods: We induced colonic tumorigenesis in C57BL/6j mice by AOM + DSS administration and evaluated the influence of reactive oxygen species on skin barrier function by using the hydroxyl radical scavenger N-acetyl-l-cysteine (NAC) or gp91phox-/- mice. Damage to the colon and skin following treatment with AOM + DSS was monitored using protein analysis methods and by detection of inflammatory mediators in the plasma. Results: NAC could not prevent the increase in transepidermal water loss (TEWL) and decrease in skin hydration level caused by AOM + DSS in gp91phox+/+ mice. However, gp91phox-/- mice showed no change in TEWL and skin hydration level. The dermal expression levels of nucleotide-binding domain, leucine-rich containing family, pyrin-domain containing 3 (NLRP3), and caspase-1 were reduced in gp91phox-/- mice. Moreover, the plasma concentrations of interleukin-18 and thymic stromal lymphopoietin (TSLP) were lower in gp91phox-/- mice than those in gp91phox+/+ mice. Inhibition of hydrogen peroxide production from superoxide anions in the gp91phox-/- status prevented the increased TEWL and decreased skin hydration level noted with degradation of NLRP3 and caspase-1. Conclusions: Superoxide anions may play an important role in the onset of the impaired skin barrier function in mice with colonic tumours.

Immunometabolism of pro-repair cells

Immune cell populations determine the balance between ongoing damage and repair following tissue injury. Cells responding to a tissue-damaged environment have significant bioenergetic and biosynthetic needs. In addition to supporting these needs, metabolic pathways govern the function of pro-repair immune cells, including regulatory T cells and tissue macrophages. In this Review, we explore how specific features of the tissue-damaged environment such as hypoxia, oxidative stress, and nutrient depletion serve as metabolic cues to promote or impair the reparative functions of immune cell populations. Hypoxia, mitochondrial DNA stress, and altered redox balance each contribute to mechanisms regulating the response to tissue damage. For example, hypoxia induces changes in regulatory T cell and macrophage metabolic profiles, including generation of 2-hydroxyglutarate, which inhibits demethylase reactions to modulate cell fate and function. Reactive oxygen species abundant in oxidative environments cause damage to mitochondrial DNA, initiating signaling pathways that likewise control pro-repair cell function. Nutrient depletion following tissue damage also affects pro-repair cell function through metabolic signaling pathways, specifically those sensitive to the redox state of the cell. The study of immunometabolism as an immediate sensor and regulator of the tissue-damaged environment provides opportunities to consider mechanisms that facilitate healthy repair of tissue injury.

Mitochondria: the indispensable players in innate immunity and guardians of the inflammatory response

Mitochondria, the dynamic organelles and power house of eukaryotic cells function as metabolic hubs of cells undergoing continuous cycles of fusion and fission. Recent findings have made it increasingly apparent that mitochondria essentially involved in energy production have evolved as principal intracellular signaling platforms regulating not only innate immunity but also inflammatory responses. Perturbations in mitochondrial dynamics, including fusion/fission, electron transport chain (ETC) architecture and cristae organization have now been actively correlated to modulate metabolic activity and immune function of innate and adaptive immune cells. Several newly identified mitochondrial proteins in mitochondrial outer membrane such as mitochondrial antiviral signaling protein (MAVS) and with mitochondrial DNA acting as danger-associated molecular pattern (DAMP) and mitochondrial ROS generated from mitochondrial sources have potentially established mitochondria as key signaling platforms in antiviral immunity in vertebrates and thereby orchestrating adaptive immune cell activations respectively. A thorough understanding of emerging and intervening role of mitochondria in toll-like receptor-mediated innate immune responses and NLRP3 inflammasome complex activation has gained lucidity in recent years that advocates the imposing functions of mitochondria in innate immunity. Fascinatingly, also how the signals stemming from the endoplasmic reticulum co-operate with the mitochondria to activate the NLRP3 inflammasome is now looked ahead as a stage to unravel as to how different mitochondrial and associated organelle stress responses co-operate to bring about inflammatory consequences. This has also opened avenues of research for revealing mitochondrial targets that could be exploited for development of novel therapeutics to treat various infectious, inflammatory, and autoimmune disorders. Thus, this review explores our current understanding of intricate interplay between mitochondria and other cellular processes like autophagy in controlling mitochondrial homeostasis and regulation of innate immunity and inflammatory responses.

Role of diagnostic factors associated with antioxidative status and expression of matrix metalloproteinases (MMPs) in patients with cancer therapy induced ocular disorders

BACKGROUND

Cancer patients when treated with different chemotherapeutic drugs often develop mild to severe sight threatening diseases during or after chemotherapy. The mechanism involved in the pathogenesis of ocular toxicities is poorly understood. Oxidative stress, inflammation and MMPs (angiogenic factor) are involved in the progression of chemotherapy related ocular disorders.

MATERIALS AND METHODS

The concentration of oxidative stress markers such as MDA, NO and levels of different antioxidant molecules such as SOD, CAT, GSH, GPx, GPr, VIT A, VIT E and VIT C present in the serum of chemotherapy treated patients (n = 50) and in normal persons (n = 20) were estimated by the direct spectrophotometric method while the concentration of TNF-α and MMP-9 activity were determined using human TNF-α and MMP-9 ELISA kits.

RESULTS

The concentration of SOD and CAT (0.356 ± 0.05 μg/dl and 1.26 ± 0.01 μmol/mol of protein) was significantly lower as compared to that (1.09 ± 0.03 μg/dl and 3.99 ± 0.04 μmol/mol of protein) in controls. The levels of GPx (0.06 ± 0.01 mmol/dl) in the cancer patients were much lower than those in the controls (0.78 ± 0.06 mmol/dl). Lower level of GSH (0.96 ± 0.003 μg/dl) in serum of the diseased group was observed as compared to healthy group (7.26 ± 1.40 μg/dl). The level of Vit A, Vit C and Vit E was lower in systemic circulation of cancer patients (109.99 ± 6.35 μg/ml, 1.26 ± 0.36 μg/ml and 1.29 ± 0.191 μg/ml) as compared to control subjects (166.35 ± 14.26 μg/ml, 3.25 ± 0.099 μg/ml and 6.354 ± 2.26 μg/ml) respectively. The concentration of nitric oxide was significantly higher in the cancer patients (45.26 ± 6.35 ng/ml) than that in the normal subjects (16.35 ± 3.26 ng/ml). The higher concentration of MDA (8.65 ± 3.26 nmol/ml) was observed in the patients than normal ones (1.254 ± 0.065 nmol/ml). The quantity of TNF-α was significantly higher in chemotherapy treated patients (32.68 ± 4.33 pg/ml) as compared to the control group (20.979 ± 1.98 pg/ml). Significantly higher concentration of MMP-9 (40.26 ± 3.26 ng/ml) was observed in the cancer patients than the controls (7.256 ± 1.95 ng/ml).

CONCLUSION

Lower levels of antioxidant enzymes and non-enzymatic small molecules and higher levels of oxidative stress and inflammatory clinical parameters such as NO, MDA, TNF-α and MMP-9 may be involved in the pathogenesis of systemic chemotherapy related ocular complications such as cataract, glaucoma, blepharitis, retinitis pigmentosa, macular degeneration, pterygium and retinal degeneration.

Potential therapy strategy: targeting mitochondrial dysfunction in sepsis

Recently, the definition of sepsis was concluded to be a life-threatening organ dysfunction caused by a dysregulated host response to infection. Severe patients always present with uncorrectable hypotension or hyperlactacidemia, which is defined as septic shock. The new definition emphasizes dysregulation of the host response and multiple organ dysfunction, which is partially attributed to metabolic disorders induced by energy crisis and oxidative stress. Mitochondria are a cellular organelle that are well known as the center of energy production, and mitochondrial damage or dysfunction is commonly induced in septic settings and is a predominant factor leading to a worse prognosis. In the present review, we determine the major mitochondrial disorders from morphology to functions in sepsis. In the following, several clinical or pre-clinical assays for monitoring mitochondrial function are demonstrated according to accumulated evidence, which is the first step of specific therapy targeting to modulate mitochondrial function. Accordingly, various reagents used for regulating mitochondrial enzyme activities and promoting biogenesis have been documented, among which mitochondria-targeted cation, TPP-conjugated antioxidants are the most valuable for future trials and clinical treatment to improve mitochondrial function as they may take advantage of the prognosis associated with septic complications.

Macrophages from the upper and lower human respiratory tract are metabolically distinct

The function and cell surface phenotype of lung macrophages vary within the respiratory tract. Alterations in the bioenergetic profile of macrophages may also be influenced by their location within the respiratory tract. This study sought to characterize the bioenergetic profile of macrophages sampled from different locations within the respiratory tract at baseline and in response to ex vivo xenobiotic challenge. Surface macrophages recovered from healthy volunteers by induced sputum and by bronchial and bronchoalveolar lavage were profiled using extracellular flux analyses. Oxygen consumption and extracellular acidification rates were measured at rest and after stimulation with lipopolysaccharide (LPS), phorbol 12-myristate 13-acetate (PMA), or 1,2-naphthoquinone (1,2-NQ). Oxygen consumption and extracellular acidification rates were highly correlated for all macrophage samples. Induced sputum macrophages had relatively higher oxygen consumption and extracellular acidification rates and were largely reliant on glycolysis. In contrast, bronchial fraction and bronchoalveolar macrophages depended more heavily on mitochondrial respiration. Bronchoalveolar macrophages showed elevated LPS-induced cytokine responses. Unlike their autologous peripheral blood monocytes, lung macrophages from any source did not display bioenergetic changes following LPS stimulation. The protein kinase C activator PMA did not affect mitochondrial respiration, whereas the air pollutant 1,2-NQ induced marked mitochondrial dysfunction in bronchoalveolar and bronchial fraction macrophages. The bioenergetic characteristics of macrophages from healthy individuals are dependent on their location within the respiratory tract. These findings establish a regional bioenergetic profile for macrophages from healthy human airways that serves as a reference for changes that occur in disease.

Transflammation: How Innate Immune Activation and Free Radicals Drive Nuclear Reprogramming

SIGNIFICANCE

Yamanaka and colleagues galvanized the field of stem cell biology and regenerative medicine by their generation of induced pluripotent stem cells. Evidence is emerging that activation of innate immune signaling is critical for efficient reprogramming to pluripotency and for the nuclear reprogramming occurring in transdifferentiation. Recent Advances: We have shown that innate immune signaling triggers a global change in the expression of epigenetic modifiers to enhance DNA accessibility. In this state of epigenetic plasticity, overexpression of lineage determination factors, and/or environmental cues and paracrine factors, can induce pluripotency, or can direct transdifferentiation to another somatic cell lineage. Accumulating evidence reveals that innate immune activation triggers the generation of reactive oxygen species and reactive nitrogen species, and that these free radicals are required for nuclear reprogramming to pluripotency or for transdifferentiation.

CRITICAL ISSUES

We have discovered a limb of innate immune signaling that regulates DNA accessibility, in part, by the action of free radicals to induce post-translational modification of epigenetic modifiers.

FUTURE DIRECTIONS

It is of scientific interest and clinical relevance to understand the mechanisms by which free radicals influence epigenetic plasticity, and how these mechanisms may be therapeutically modulated. Antioxid. Redox Signal. 00, 000-000.

The Role of Mitophagy in Innate Immunity

Mitochondria are cellular organelles essential for multiple biological processes, including energy production, metabolites biosynthesis, cell death, and immunological responses among others. Recent advances in the field of immunology research reveal the pivotal role of energy metabolism in innate immune cells fate and function. Therefore, the maintenance of mitochondrial network integrity and activity is a prerequisite for immune system homeostasis. Mitochondrial selective autophagy, known as mitophagy, surveils mitochondrial population eliminating superfluous and/or impaired organelles and mediating cellular survival and viability in response to injury/trauma and infection. Defective removal of damaged mitochondria leads to hyperactivation of inflammatory signaling pathways and subsequently to chronic systemic inflammation and development of inflammatory diseases. Here, we review the molecular mechanisms of mitophagy and highlight its critical role in the innate immune system homeostasis.

Live Imaging of Label-Free Graphene Oxide Reveals Critical Factors Causing Oxidative-Stress-Mediated Cellular Responses

The interest in graphene and its translation into commercial products has been expanding at a high pace. Based on previously described pulmonary safety concerns for carbon nanomaterials, there is a great need to define parameters guiding interactions between graphene-based materials and the pulmonary system. The aim of the present study was to determine the importance of two critical parameters: lateral dimensions of the material and coating with proteins in relation to each other and their pulmonary impact. Endotoxin-free materials with distinct lateral dimensions, s-GO (50-200 nm) and l-GO (5-15 μm), were produced and thoroughly characterized. Exploiting intrinsic fluorescence of graphene oxide (GO) and using confocal live-cell imaging, the behavior of the cells in response to the material was visualized in real time. Although BEAS-2B cells internalized GO efficiently, l-GO was linked to higher plasma membrane interactions correlated with elevated reactive oxygen species (ROS) levels, pro-inflammatory response, and greater cytotoxicity, in agreement with the oxidative stress paradigm. For both GO types, the presence of serum alleviated lipid peroxidation of plasma membrane and decreased intracellular ROS levels. However, protein coating was not enough to entirely mitigate toxicity and inflammatory response induced by l-GO. In vitro results were validated in vivo, as l-GO was more prone to induce pulmonary granulomatous response in mice compared to s-GO. In conclusion, the lateral dimension of GO played a more important role than serum protein coating in determining biological responses to the material. It was also demonstrated that time-lapse imaging of live cells interacting with label-free GO sheets can be used as a tool to assess GO-induced cytotoxicity.

Ageing of the carotid body

The ageing process is characterized by a decline in several physiological functions resulting in a reduced capability to maintain homeostasis. The lowered homeostatic capacity seems to involve the carotid body (CB), whose role is to modulate ventilation and tissue oxygen supply. It thus plays a prime role in all ageing processes. Ageing causes marked changes in CB morphology. In older animals, it is enlarged and shows a concomitant decrease in the percentage of chemoreceptor tissue, as well as a proliferation of type II cells. The carotid glomitis is present with aggregates of lymphocytes and fibrosis of the lobules. Type I cells are dehydrated, with a profound vacuolization, a shrinking nucleus, and lipofuscin accumulation. With increased age, human CB shows a reduction in the number and volume of mitochondria, fewer synaptic junctions between glomi, along with a reduction in CB content of neurotransmitters, leading to a sort of 'physiological denervation'. Ageing could be interpreted as a cumulative result of oxidative damage to cells, which derives from aerobic metabolism. Moreover, metabolic rate is tightly correlated with life duration; thus a loss in mitochondrial function is one of the prime factors affecting CB ageing processes. The age-related reduction in synaptic junctions might be a self-protective mechanism through which cells buffer themselves against an accumulation of reactive oxygen species. The correlation between hypoxia and the life duration of CB cells remains an open question until how and why cells sense oxygen is understood.

Oxidative stress and cellular pathways of asthma and inflammation: Therapeutic strategies and pharmacological targets

Asthma is a complex inflammatory disease characterized by airway inflammation and hyperresponsiveness. The mechanisms associated with the development and progression of asthma have been widely studied in multiple populations and animal models, and these have revealed involvement of various cell types and activation of intracellular signaling pathways that result in activation of inflammatory genes. Significant contributions of Toll-like-receptors (TLRs) and transcription factors such as NF-кB, have been reported as major contributors to inflammatory pathways. These have also recently been associated with mechanisms of oxidative biology. This is of important clinical significance as the observed inefficacy of current available treatments for severe asthma is widely attributed to oxidative stress. Therefore, targeting oxidizing molecules in conjunction with inflammatory mediators and transcription factors may present a novel therapeutic strategy for asthma. In this review, we summarize TLRs and NF-кB pathways in the context of exacerbation of asthma pathogenesis and oxidative biology, and we discuss the potential use of polyphenolic flavonoid compounds, known to target these pathways and possess antioxidant activity, as potential therapeutic agents for asthma.

Roles of TRAF6 in Central Nervous System

Tumor necrosis factor receptor-associated factor (TRAF) is an important binding protein of tumor necrosis factor (TNF) superfamily and the toll/IL-1 receptor (TIR) superfamily, which play an important role in innate immunity and acquired immunity. TRAFs family have 7 members (TRAF1-7), and TRAF6 has its special facture and biological function. TRAF6 has two special domains: C-terminal domain and N-terminal domain, which could integrate with multiple kinases and regulate signaling pathway function as an E3 ubiquitin ligase. Studies have increasingly found that TRAF6 is closely related to central nervous system diseases, such as stroke, Traumatic brain injury, neurodegenerative diseases and neuropathic pain. Further research on the pathophysiological mechanism may be expected to become the new targets for the treatment of central nervous system diseases.

Regulation of ASK1 signaling by scaffold and adaptor proteins

The mitogen-activated protein kinase (MAPK) signaling pathway is a three-tiered kinase cascade where mitogen-activated protein kinase kinase kinases (MAP3Ks) lead to the activation of mitogen-activated protein kinase kinases (MAP2K), and ultimately MAPK proteins. MAPK signaling can promote a diverse set of biological outcomes, ranging from cell death to proliferation. There are multiple mechanisms which govern MAPK output, such as the duration and strength of the signal, cellular localization to upstream and downstream binding partners, pathway crosstalk and the binding to scaffold and adaptor molecules. This review will focus on scaffold and adaptor proteins that bind to and regulate apoptosis signal-regulating kinase 1 (ASK1), a MAP3K protein with a critical role in mediating stress response pathways.

Inflammation-Induced Oxidative Stress Mediates Gene Fusion Formation in Prostate Cancer

Approximately 50% of prostate cancers are associated with gene fusions of the androgen-regulated gene TMPRSS2 to the oncogenic erythroblast transformation-specific (ETS) transcription factor ERG. The three-dimensional proximity of TMPRSS2 and ERG genes, in combination with DNA breaks, facilitates the formation of TMPRSS2-ERG gene fusions. However, the origins of DNA breaks that underlie gene fusion formation in prostate cancers are far from clear. We demonstrate a role for inflammation-induced oxidative stress in the formation of DNA breaks leading to recurrent TMPRSS2-ERG gene fusions. The transcriptional status and epigenetic features of the target genes influence this effect. Importantly, inflammation-induced de novo genomic rearrangements are blocked by homologous recombination (HR) and promoted by non-homologous end-joining (NHEJ) pathways. In conjunction with the association of proliferative inflammatory atrophy (PIA) with human prostate cancer, our results support a working model in which recurrent genomic rearrangements induced by inflammatory stimuli lead to the development of prostate cancer.

Cytotoxicity, Oxidative Stress, Cell Cycle Arrest, and Mitochondrial Apoptosis after Combined Treatment of Hepatocarcinoma Cells with Maleic Anhydride Derivatives and Quercetin

The inflammatory condition of malignant tumors continually exposes cancer cells to reactive oxygen species, an oxidizing condition that leads to the activation of the antioxidant defense system. A similar activation occurs with glutathione production. This oxidant condition enables tumor cells to maintain the energy required for growth, proliferation, and evasion of cell death. The objective of the present study was to determine the effect on hepatocellular carcinoma cells of a combination treatment with maleic anhydride derivatives (prooxidants) and quercetin (an antioxidant). The results show that the combination of a prooxidant/antioxidant had a cytotoxic effect on HuH7 and HepG2 liver cancer cells, but not on either of two normal human epithelial cell lines or on primary hepatocytes. The combination treatment triggered apoptosis in hepatocellular carcinoma cells by activating the intrinsic pathway and causing S phase arrest during cell cycle progression. There is also clear evidence of a modification in cytoskeletal actin and nucleus morphology at 24 and 48 h posttreatment. Thus, the current data suggest that the combination of two anticarcinogenic drugs, a prooxidant followed by an antioxidant, can be further explored for antitumor potential as a new treatment strategy.