Age-associated neurodegeneration and oxidative damage to lipids, proteins and DNA

Oxidatively-induced DNA base damage and base excision repair abnormalities in siblings of individuals with bipolar disorder DNA damage and repair in bipolar disorder

Previous evidence suggests elevated levels of oxidatively-induced DNA damage, particularly 8-hydroxy-2'-deoxyguanosine (8-OH-dG), and abnormalities in the repair of 8-OH-dG by the base excision repair (BER) in bipolar disorder (BD). However, the genetic disposition of these abnormalities remains unknown. In this study, we aimed to investigate the levels of oxidatively-induced DNA damage and BER mechanisms in individuals with BD and their siblings, as compared to healthy controls (HCs). 46 individuals with BD, 41 siblings of individuals with BD, and 51 HCs were included in the study. Liquid chromatography-tandem mass spectrometry was employed to evaluate the levels of 8-OH-dG in urine, which were then normalized based on urine creatinine levels. The real-time-polymerase chain reaction was used to measure the expression levels of 8-oxoguanine DNA glycosylase 1 (OGG1), apurinic/apyrimidinic endonuclease 1 (APE1), poly ADP-ribose polymerase 1 (PARP1), and DNA polymerase beta (POLβ). The levels of 8-OH-dG were found to be elevated in both individuals with BD and their siblings when compared to the HCs. The OGG1 and APE1 expressions were downregulated, while POLβ expressions were upregulated in both the patient and sibling groups compared to the HCs. Age, smoking status, and the number of depressive episodes had an impact on APE1 expression levels in the patient group while body mass index, smoking status, and past psychiatric history had an impact on 8-OH-dG levels in siblings. Both individuals with BD and unaffected siblings presented similar abnormalities regarding oxidatively-induced DNA damage and BER, suggesting a link between abnormalities in DNA damage/BER mechanisms and familial susceptibility to BD. Our findings suggest that targeting the oxidatively-induced DNA damage and BER pathway could offer promising therapeutic strategies for reducing the risk of age-related diseases and comorbidities in individuals with a genetic predisposition to BD.

Oxidative stress in the brain-lung crosstalk: cellular and molecular perspectives

Oxidative stress is caused by an imbalance between the production of reactive oxygen species (ROS) and the body's ability to counteract their harmful effects, playing a key role in the pathogenesis of brain and lung-related diseases. This review comprehensively examines the intricate mechanisms by which oxidative stress influences cellular and molecular pathways, contributing to neurodegenerative, cardiovascular, and respiratory disorders. Emphasizing the detrimental effects on both brain and lung health, we discuss innovative diagnostic biomarkers, such as 8-hydroxy-2'-deoxyguanosine (8-OHdG), and the potential of antioxidant therapies. For these topics, we provide insights into future research directions in the field of oxidative stress treatment, including the development of personalized treatment approaches, the discovery and validation of novel biomarkers, and the development of new drug delivery systems. This review not only provides a new perspective on understanding the role of oxidative stress in brain and lung-related diseases but also offers new insights for future clinical treatments.

Catalytic activity of OGG1 is impaired by Zinc deficiency

Oxidative stress-induced DNA base modifications, if unrepaired, can increase mutagenesis and genomic instability, ultimately leading to cell death. Cells predominantly use the base excision repair (BER) pathway to repair oxidatively-induced non-helix distorting lesions. BER is initiated by DNA glycosylases, such as 8-oxoguanine DNA glycosylase (OGG1), which repairs oxidatively modified guanine bases, including 7,8-dihydro-8-oxoguanine (8-oxoG) and ring-opened formamidopyrimidine lesions, 2,6-diamino-4-hydroxy-5-formamidopyrimidine (FapyG). The OGG1 protein contains a C2H2 zinc (Zn) finger DNA binding domain. However, the impact of dietary Zn deficiency on OGG1 catalytic activity has not been extensively studied. Zn is a common nutrient of concern with increasing age, and the prevalence of oxidative DNA damage is also concurrently increased during aging. Thus, understanding the potential regulation of OGG1 activity by Zn is clinically relevant. The present study investigates the impact of a range of Zn statuses, varying from severe Zn deficiency to exogenous Zn-supplementation, in the context of young and aged animals to determine the impact of dietary Zn-status on OGG1 activity and oxidative DNA damage in mice. Our findings suggest that nutritional Zn deficiency impairs OGG1 activity and function, without altering gene expression, and that aging further exacerbates these effects. These results have important implications for nutritional management of Zn during aging to mitigate age-associated DNA damage.

CKLF1, transcriptionally activated by FOXC1, promotes hypoxia/reoxygenation‑induced oxidative stress and inflammation in H9c2 cells by NLRP3 inflammasome activation

Myocardial ischemia/reperfusion (I/R) injury is a clinical challenge in the treatment of ischemic heart disease. The present study aimed to establish a hypoxia/reoxygenation (H/R)-induced H9c2 cell model to explore the role and mechanism of chemokine-like factor 1 (CKLF1) in myocardial I/R injury. First, CKLF1 expression was measured in H/R-induced H9c2 cells by reverse transcription-quantitative PCR and western blotting. Subsequently, after CKLF1 silencing, cell viability and apoptosis were evaluated by Cell Counting Kit-8 assay and flow cytometry. In addition, 2,7-dichlorodihydrofluorescein diacetate staining was used to assess the levels of cellular reactive oxygen species. Additionally, the levels of superoxide dismutase, glutathione peroxidase and malondialdehyde, and the contents of inflammatory factors IL-6, IL-1β and TNF-α were detected using corresponding commercially available kits. Western blotting was used to examine the expression levels of proteins involved in the NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome. The JASPAR database predicted that forkhead box protein C1 (FOXC1) would bind to the CKLF1 promoter region, and dual luciferase and chromatin immunoprecipitation assays were performed to verify it. Subsequently, FOXC1 overexpression and CKLF1 silencing were used to clarify the regulatory mechanism of FOXC1 on CKLF1 in H/R-induced H9c2 cells. The results revealed that CKLF1 expression was markedly enhanced in H/R-stimulated H9c2 cells. CKLF1 knockdown enhanced the viability and inhibited the apoptosis of H9c2 cells exposed to H/R. Moreover, the oxidative stress and inflammation induced by H/R were alleviated following CKLF1 silencing. CKLF1 knockdown also inhibited NLRP3 inflammasome activation. Furthermore, FOXC1 bound to the CKLF1 promoter region to upregulate CKLF1 expression, and FOXC1 overexpression alleviated the effects of CKLF1 knockdown on H9c2 cell damage induced by H/R via activation of the NLRP3 inflammasome. In conclusion, CKLF1 transcriptionally activated by FOXC1 may promote H/R-induced oxidative stress and inflammation in H9c2 cells via NLRP3 inflammasome activation.

Antioxidant peptides, the guardian of life from oxidative stress

Reactive oxygen species (ROS) are produced during oxidative metabolism in aerobic organisms. Under normal conditions, ROS production and elimination are in a relatively balanced state. However, under internal or external environmental stress, such as high glucose levels or UV radiation, ROS production can increase significantly, leading to oxidative stress. Excess ROS production not only damages biomolecules but is also closely associated with the pathogenesis of many diseases, such as skin photoaging, diabetes, and cancer. Antioxidant peptides (AOPs) are naturally occurring or artificially designed peptides that can reduce the levels of ROS and other pro-oxidants, thus showing great potential in the treatment of oxidative stress-related diseases. In this review, we discussed ROS production and its role in inducing oxidative stress-related diseases in humans. Additionally, we discussed the sources, mechanism of action, and evaluation methods of AOPs and provided directions for future studies on AOPs.

Melatonin and ferroptosis: Mechanisms and therapeutic implications

Ferroptosis, a regulated form of cell death, is characterized by iron-dependent lipid peroxidation leading to oxidative damage to cell membranes. Cell sensitivity to ferroptosis is influenced by factors such as iron overload, lipid metabolism, and the regulation of the antioxidant system. Melatonin, with its demonstrated capacity to chelate iron, modulate iron metabolism proteins, regulate lipid peroxidation, and regulate antioxidant systems, has promise as a potential therapeutic agent in mediating ferroptosis. The availability of approved drugs targeting ferroptosis is limited; therefore, melatonin is a candidate for broad application due to its safety and efficacy in attenuating ferroptosis in noncancerous diseases. Melatonin has been demonstrated to attenuate ferroptosis in cellular and animal models of noncancerous diseases, showcasing effectiveness in organs such as the heart, brain, lung, liver, kidney, and bone. This review outlines the molecular mechanisms of ferroptosis, investigates melatonin's potential effects on ferroptosis, and discusses melatonin's therapeutic potential as a promising intervention against diseases associated with ferroptosis. Through this discourse, we aim to lay a strong foundation for developing melatonin as a therapeutic strategy to modulate ferroptosis in a variety of disease contexts.

Tanshinone IIA suppresses burning incense-induced oxidative stress and inflammatory pathways in astrocytes

The burning incense (BI) behavior could be widely observed in Asia families. Incense sticks are often believed to be made from natural herbs and powders, and to have minimal impact on human health; however, there is limited research to support this claim. The current study aimed to identify the components of BI within the particulate matter 2.5 µm (PM_2.5) range and explore if BI has bio-toxicity effects on rat astrocytes (CTX-TNA2). The study also examined the protective effects and underlying molecular mechanisms of tanshinone IIA, a primary lipid-soluble compound found in the herb danshen (Salvia miltiorrhiza Bunge), which has been shown to benefit the central nervous system. Results showed that despite the differences in BI components compared to the atmospheric particulate matter (PM) standards, BI still had a bio-toxicity on astrocytes. BI exposure caused early and late apoptosis, reactive oxygen species (ROS) production, MAPKs (JNK, p38, and ERK), and Akt signaling activation, and inflammation-related proteins (cPLA2, COX-2, HO-1, and MMP-9) increases. Our results further exhibit that the tanshinone IIA pre-treatment could significantly avoid the BI-induced apoptosis and inflammatory signals on rat astrocytes. These findings suggest that BI exposure may cause oxidative stress in rat astrocytes and increase inflammation-related proteins and support the potential of tanshinone IIA as a candidate for preventing BI-related adverse health effects.

Cellular mechanisms in brain aging: Focus on physiological and pathological aging

Aging is a natural phenomenon characterized by accumulation of cellular damage and debris. Oxidative stress, cellular senescence, sustained inflammation, and DNA damage are the main cellular processes characteristic of aging associated with morphological and functional decline. These effects tend to be more pronounced in tissues with high metabolic rates such as the brain, mainly in regions such as the prefrontal cortex, hippocampus, and amygdala. These regions are highly related to cognitive behavior, and therefore their atrophy usually leads to decline in processes such as memory and learning. These cognitive declines can occur in physiological aging and are exacerbated in pathological aging. In this article, we review the cellular processes that underlie the triggers of aging and how they relate to one another, causing the atrophy of nerve tissue that is typical of aging. The main topic of this review to determine the central factor that triggers all the cellular processes that lead to cellular aging and discriminate between normal and pathological aging. Finally, we review how the use of supplements with antioxidant and anti-inflammatory properties reduces the cognitive decline typical of aging, which reinforces the hypothesis of oxidative stress and cellular damage as contributors of physiological atrophy of aging. Moreover, cumulative evidence suggests their possible use as therapies, which improve the aging population's quality of life.

Antioxidant and Antidiabetic Properties of Extracts from Three Underutilized Food Plants of North East India

Three underutilized leafy vegetables Sarcochlamys pulcherrima (Roxb.) Gaudich (SP), Ipomoea aquatica Forssk. (IA) and Zanthoxylum rhetsa (Roxb.) DC (ZR) were extracted with different solvents viz. 95 % ethyl alcohol, methanol and hot water. The extracts were evaluated for their antioxidant potential via DPPH, ABTS and FRAP assay along with electroanalytical studies using cyclic voltammetry. The antidiabetic potential was determined by recording their α-amylase and α-glucosidase inhibitory assay. The total phenolic content (TPC), total flavonoid content (TFC) and the liquid chromatography-mass spectrometry (LC/MS) based phytochemical profiles of the extracts were also determined. All three extracts of SP exhibited significant antioxidant capacity. The antidiabetic potential of the IA and ZR extracts was found to be higher than or at par with that of standard acarbose. LC/MS studies reveal the presence of hitherto reported antioxidant and antidiabetic compounds like gamma-aminobutyric acid, cinnamic acid, caffeic acid, α-viniferin, piperlonguminine, niacin, kaempferol, etc., in the extracts.

Recent Advances in the Study of Na+/K+-ATPase in Neurodegenerative Diseases

Na⁺/K⁺-ATPase (NKA), a large transmembrane protein, is expressed in the plasma membrane of most eukaryotic cells. It maintains resting membrane potential, cell volume and secondary transcellular transport of other ions and neurotransmitters. NKA consumes about half of the ATP molecules in the brain, which makes NKA highly sensitive to energy deficiency. Neurodegenerative diseases (NDDs) are a group of diseases characterized by chronic, progressive and irreversible neuronal loss in specific brain areas. The pathogenesis of NDDs is sophisticated, involving protein misfolding and aggregation, mitochondrial dysfunction and oxidative stress. The protective effect of NKA against NDDs has been emerging gradually in the past few decades. Hence, understanding the role of NKA in NDDs is critical for elucidating the underlying pathophysiology of NDDs and identifying new therapeutic targets. The present review focuses on the recent progress involving different aspects of NKA in cellular homeostasis to present in-depth understanding of this unique protein. Moreover, the essential roles of NKA in NDDs are discussed to provide a platform and bright future for the improvement of clinical research in NDDs.

Markers of elevated oxidative stress in oligodendrocytes captured from the brainstem and occipital cortex in major depressive disorder and suicide

Major depressive disorder (MDD) and suicide have been associated with elevated indices of oxidative damage in the brain, as well as white matter pathology including reduced myelination by oligodendrocytes. Oligodendrocytes highly populate white matter and are inherently susceptible to oxidative damage. Pathology of white matter oligodendrocytes has been reported to occur in brain regions that process behaviors that are disrupted in MDD and that may contribute to suicidal behavior. The present study was designed to determine whether oligodendrocyte pathology related to oxidative damage extends to brain areas outside of those that are traditionally considered to contribute to the psychopathology of MDD and suicide. Relative telomere lengths and the gene expression of five antioxidant-related genes, SOD1, SOD2, GPX1, CAT, and AGPS were measured in oligodendrocytes laser captured from two non-limbic brain areas: occipital cortical white matter and the brainstem locus coeruleus. Postmortem brain tissues were obtained from brain donors that died by suicide and had an active MDD at the time of death, and from psychiatrically normal control donors. Relative telomere lengths were significantly reduced in oligodendrocytes of both brain regions in MDD donors as compared to control donors. Three antioxidant-related genes (SOD1, SOD2, GPX1) were significantly reduced and one was significantly elevated (AGPS) in oligodendrocytes from both brain regions in MDD as compared to control donors. These findings suggest that oligodendrocyte pathology in MDD and suicide is widespread in the brain and not restricted to brain areas commonly associated with depression psychopathology.

Functional role of the SLC7A11-AS1/xCT axis in the development of gastric cancer cisplatin-resistance by a GSH-dependent mechanism

Resistance to platinum-based chemotherapy is a major obstacle in gastric cancer (GC) treatment. Abundant long noncoding RNAs (lncRNAs) are reported to play important roles in tumorigenesis and drug resistance biology. Herein, we report that the SLC7A11-AS1 and xCT are involved in cisplatin resistance in GC. SLC7A11-AS1 was downregulated and xCT was upregulated in cisplatin-resistant GC tissues and cell lines. GC patients with low expression of SLC7A11-AS1 and high expression of xCT had a poor prognosis and relatively poor response to chemotherapy. Overexpression of SLC7A11-AS1 weakened GC growth, reduced intracellular GSH biosynthesis, enhanced intracellular reactive oxygen species (ROS) and conferred sensitivity to cisplatin to resistant GC cells in vitro and in vivo. Mechanistically, SLC7A11-AS1 directly suppressed xCT expression, while miR-33a-5p remarkably reduced SLC7A11-AS1 and xCT expression by directly targeting the SLC7A11-AS1 and xCT 3'UTRs. In addition, we found that low SLC7A11-AS1 expression activated the p38MAPK-JNK signaling pathway, and increased the expression of cisplatin export gene ATP7A and the GSH biosynthesis gene GCLM in GC.

Quantification of 8-oxoG in Plant Telomeres

Chemical modifications in DNA impact gene regulation and chromatin structure. DNA oxidation, for example, alters gene expression, DNA synthesis and cell cycle progression. Modification of telomeric DNA by oxidation is emerging as a marker of genotoxic damage and is associated with reduced genome integrity and changes in telomere length and telomerase activity. 8-oxoguanine (8-oxoG) is the most studied and common outcome of oxidative damage in DNA. The G-rich nature of telomeric DNA is proposed to make it a hotspot for oxidation, but because telomeres make up only a tiny fraction of the genome, it has been difficult to directly test this hypothesis by studying dynamic DNA modifications specific to this region in vivo. Here, we present a new, robust method to differentially enrich telomeric DNA in solution, coupled with downstream methods for determination of chemical modification. Specifically, we measure 8-oxoG in Arabidopsis thaliana telomeres under normal and oxidative stress conditions. We show that telomere length is unchanged in response to oxidative stress in three different wild-type accessions. Furthermore, we report that while telomeric DNA comprises only 0.02–0.07% of the total genome, telomeres contribute between 0.2 and 15% of the total 8-oxoG. That is, plant telomeres accumulate 8-oxoG at levels approximately 100-fold higher than the rest of the genome under standard growth conditions. Moreover, they are the primary targets of further damage upon oxidative stress. Interestingly, the accumulation of 8-oxoG in the chromosome body seems to be inversely proportional to telomere length. These findings support the hypothesis that telomeres are hotspots of 8-oxoG and may function as sentinels of oxidative stress in plants.

Nobiletin Alleviates Astrocyte Activation and Oxidative Stress Induced by Hypoxia In Vitro

Increasing evidence indicates that nobiletin (NOB) is a promising neuroprotective agent. Astrocyte activation plays a key role in neurodegenerative disorders. Thus, this study aims to investigate the effects of NOB on astrocyte activation and the potential mechanisms. In this study, astrocytes were exposed to hypoxia injury for 24 h to induce activation in vitro. Glial fibrillary acidic protein (GFAP) was chosen as a marker of astrocyte activation. To evaluate the effects of NOB on the migration of activated astrocytes, we used a scratch wound healing assay and Transwell migration assay. In addition, the levels of reactive oxygen species (ROS), malondialdehyde (MDA), mitochondrial membrane potential, Nrf2 and HO-1 were measured to investigate the mechanisms of NOB in the activation of astrocytes. We found that NOB alleviated astrocyte activation and decreased GFAP expression during hypoxia. Simultaneously, NOB alleviated the migration of astrocytes induced by hypoxia. With NOB treatment, hypoxia-induced oxidative stress was partially reversed, including reducing the production of ROS and MDA. Furthermore, NOB significantly improved the mitochondrial dysfunction in activated astrocytes. Finally, NOB promoted Nrf2 nuclear translocation and HO-1 expression in response to continuous oxidative damage. Our study indicates, for the first time, that NOB alleviates the activation of astrocytes induced by hypoxia in vitro, in part by ameliorating oxidative stress and mitochondrial dysfunction. This provides new insights into the neuroprotective effects of NOB.

Are Methionine Sulfoxide-Containing Proteins Related to Seed Longevity? A Case Study of Arabidopsisthaliana Dry Mature Seeds Using Cyanogen Bromide Attack and Two-Dimensional-Diagonal Electrophoresis

In recent years, several reports pointed out the role of protein oxidation in seed longevity, notably regarding the oxidation of methionine (Met) residues to methionine sulfoxide (MetO) in proteins. To further consider this question, we present a handy proteomic method based on the use of two-dimensional diagonal electrophoresis (2Dd) and cyanogen bromide (CNBr) cleavage, which we refer to as 2Dd-CNBr. CNBr treatment of proteins causes the non-enzymatic hydrolysis of peptide bonds on the carboxyl side of reduced Met residues. However, Met oxidation causes a lack of cleavage, thus modifying the electrophoretic mobility of CNBr-induced peptides. This approach was first validated using bovine serum albumin as a model protein, which confirmed the possibility of distinguishing between oxidized and non-oxidized forms of Met-containing peptides in gels. Then, the 2Dd-CNBr method was applied to the Arabidopsis thaliana seed protein extract in a control (non-oxidized) condition and in an oxidized one (as obtained following hypochlorous acid treatment). Twenty-four oxidized Met residues in 19 proteins identified by mass spectrometry were found to be surface exposed in these proteins. In the three-dimensional environment of the oxidized Met, we detected amino acid residues that could be converted by oxidation (carbonylation) or by phosphorylation, suggesting a possible interplay between Met oxidation and the other protein modifications. The identification of the proteins oxidatively modified in Met residues revealed the finding that MetO-containing proteins are related to seed longevity. Based on these results, we suggest that the method presently described also has the potential for wider applications.

Issues on Trainability

Trainability is an adaptive response to given exercise loads and must be localized to the targeted physiological function since exercise-induced acute and chronic adaptations are systemic. Lack of adaptation or moderate level of adaptation in one organ or one physiological function would not mean that other organs or functions would not benefit from exercise training. The most beneficial training load could easily be different for skeletal muscle, brain, the gastro-intestinal track, or the immune systems. Hence, the term of non-responders should be used with caution and just referred to a given organ, cell type, molecular signaling, or function. The present paper aims to highlight some, certainly not all, issues on trainability especially related to muscle and cardiovascular system. The specificity of trainability and the systemic nature of exercise-induced adaptation are discussed, and the paper aims to provide suggestions on how to improve performance when faced with non-responders.

MsrB1 Promotes Proliferation and Invasion of Colorectal Cancer Cells via GSK-3β/β-catenin Signaling Axis

Methionine sulfoxide reductase B1 (MsrB1) can catalyze both free and protein-bound R-methionine sulfoxides (R-MetO) to methionine (Met). It has been reported that MsrB1 plays an important role in the development of HCC and human bone osteosarcoma. However, little is known about the functions of MsrB1 in human colorectal cancer (CRC). Herein, we detected MsrB1 expression level in CRC tissue and cell lines, and investigated the effect of MsrB1 knockdown on CRC phenotypes and possible mechanisms involved in. The results showed that MsrB1 was highly expressed in both CRC tissues and cell lines, and that cell proliferation, migration and invasion were significantly inhibited, but apoptosis was increased after MsrB1 knockdown in colorectal cancer HCT116 and RKO cell lines, compared to control siRNA group. In addition, E-cadherin protein level was increased, vimentin and Snail protein were greatly decreased after knockdown of MsrB1 in cells. Furthermore, pGSK-3β (Ser9) and β-catenin protein levels were reduced, the promoter activity of TCF/LEF construction was inhibited after MsrB1 knockdown in cells, suggesting that GSK-3β/β-catenin signaling axis was involved in the tumorigenesis of CRC. In conclusion, the oncogenic role and related mechanisms of MsrB1 in CRC discovered in our work determined the potential role of MsrB1 as a biomarker and may provide a new target for clinical therapy of CRC.

[Oxidative stress in schizophrenia as a promising target for psychopharmacotherapy]

Until now, only dopamine receptor blockers are used for psychopharmacotherapy of schizophrenia, despite the active search for alternative pharmacological agents and a lot of research. However, most of these studies concerned molecules that somehow affect various neurotransmitter receptors. In addition, various anti-inflammatory drugs have been studied quite actively. At the same time, attempts to correct oxidative stress are given significantly less attention, although the emergence of the latter is facilitated by completely different pathophysiological processes and environmental factors associated with the development of schizophrenia. NMDA receptor blockage, vitamin D deficiency, social isolation, chronic stress in adolescence, inflammation, perinatal infection etc. - all this can ultimately lead to the occurrence of oxidative stress. However, there is a significant difference in the severity of this process depending on the stage of the course of schizophrenia, which probably partially explains the heterogeneity of results of the studies on the oxidative stress biomarkers in this disorder. In order to overcome these methodological problems, it seems promising to conduct double-blind studies of the effectiveness of antioxidants in schizophrenia with the selection of groups of patients taking into account the stage of the disorder and the level of certain biomarkers of oxidative stress (F2-isoprostanes, 8-oxodG, 8-oxoGuo). The optimal pharmacological agents for such studies are N-acetylcysteine due to the positive results of previous studies, and melatonin as an antioxidant with a unique activity profile.

Biomolecular Modifications Linked to Oxidative Stress in Amyotrophic Lateral Sclerosis: Determining Promising Biomarkers Related to Oxidative Stress

Reduction–oxidation reactions are essential to cellular homeostasis. Oxidative stress transcends physiological antioxidative system damage to biomolecules, including nucleic acids and proteins, and modifies their structures. Amyotrophic lateral sclerosis (ALS) is the most common adult-onset motor neuron disease. The cells present in the central nervous system, including motor neurons, are vulnerable to oxidative stress. Neurodegeneration has been demonstrated to be caused by oxidative biomolecular modifications. Oxidative stress has been suggested to be involved in the pathogenesis of ALS. Recent progress in research on the underlying mechanisms of oxidative stress in ALS has led to the development of disease-modifying therapies, including edaravone. However, the clinical effects of edaravone remain limited, and ALS is a heretofore incurable disease. The reason for the lack of reliable biomarkers and the precise underlying mechanisms between oxidative stress and ALS remain unclear. As extracellular proteins and RNAs present in body fluids and represent intracellular pathological neurodegenerative processes, extracellular proteins and/or RNAs are predicted to promise diagnosis, prediction of disease course, and therapeutic biomarkers for ALS. Therefore, we aimed to elucidate the underlying mechanisms between oxidative stress and ALS, and promising biomarkers indicating the mechanism to determine whether therapy targeting oxidative stress can be fundamental for ALS.

Specific microglial phagocytic phenotype and decrease of lipid oxidation in white matter areas during aging: Implications of different microenvironments

Physiological aging is characterized by an imbalance of pro-inflammatory and anti-inflammatory mediators leading to neuroinflammation. Microglial cells, which are highly regulated by the local microenvironment, undergo specific changes depending upon the brain area during aging. The aim of this study was to evaluate the influence of age over microglial cells along different brain areas and microenvironments. For this purpose, transgenic mice with overproduction of either the anti-inflammatory IL-10 cytokine or the pro-inflammatory IL-6 cytokine were used. Our results show that, during aging, microglial cells located in white matter (WM) areas maintain their phagocytic capacity but present a specific phagocytic phenotype with receptors involved in myelin recognition, arguing for aging-derived myelin damage. Whereas IL-10 overproduction anticipates the age-related microglial phagocytic phenotype, maintaining it over time, IL-6 overproduction exacerbates this phenotype in aging. These modifications were linked with a higher efficiency of myelin engulfment by microglia in aged transgenic animals. Moreover, we show, in a novel way, lower lipid oxidation during aging in WM areas, regardless of the genotype. The novelty of the insights presented in this study open a window to deeply investigate myelin lipid oxidation and the role of microglial cells in its regulation during physiological aging.

Thioredoxin reductase as a pharmacological target

Thioredoxin reductases (TrxRs) belong to the pyridine nucleotide disulfide oxidoreductase family enzymes that reduce thioredoxin (Trx). The couple TrxR and Trx is one of the major antioxidant systems that control the redox homeostasis in cells. The thioredoxin system, comprised of TrxR, Trx and NADPH, exerts its activities via a disulfide-dithiol exchange reaction. Inhibition of TrxR is an important clinical goal in all conditions in which the redox state is perturbed. The present review focuses on the most critical aspects of the cellular functions of TrxRs and their inhibition mechanisms by metal ions or chemicals, through direct targeting of TrxRs or their substrates or protein interactors. To update the involvement of overactivation/dysfunction of TrxRs in various pathological conditions, human diseases associated with TrxRs genes were critically summarized by publicly available genome-wide association study (GWAS) catalogs and literature. The pieces of evidence presented here justify why TrxR is recognized as one of the most critical clinical targets and the growing current interest in developing molecules capable of interfering with the functions of TrxR enzymes.

Design, synthesis, and cholinesterase inhibition assay of liquiritigenin derivatives as anti-Alzheimer's activity

The marine environment is a rich resource for discovering functional materials, and seaweed is recognized for its potential use in biology and medicine. Liquiritigenin has been isolated and identified from Sargassum pallidum. To find new anti-Alzheimer's activity, we designed and synthesized thirty-two 7-prenyloxy-2,3-dihydroflavanone derivatives (3a-3p) and 5-hydroxy-7-prenyloxy-2,3-dihydro- flavanone derivatives (4a-4p) as cholinesterases inhibitors based on liquiritigenin as the lead compound. Inhibition screening against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) indicated that all synthesized compounds possessed potent AChE inhibitory activity and moderated to weak BuChE inhibitory activity in vitro. Kinetic studies demonstrated that compound 4o inhibited AChE via a dual binding site ability. In addition, all compounds displayed the radical scavenging effects. Finally, the molecular docking simulation of 4o in AChE active site displayed good agreement with the obtained the pharmacological results.

Recent insights on astrocyte mechanisms in CNS homeostasis, pathology, and repair

Astrocytes play essential roles in development, homeostasis, injury, and repair of the central nervous system (CNS). Their development is tightly regulated by distinct spatial and temporal cues during embryogenesis and into adulthood throughout the CNS. Astrocytes have several important responsibilities such as regulating blood flow and permeability of the blood-CNS barrier, glucose metabolism and storage, synapse formation and function, and axon myelination. In CNS pathologies, astrocytes also play critical parts in both injury and repair mechanisms. Upon injury, they undergo a robust phenotypic shift known as "reactive astrogliosis," which results in both constructive and deleterious outcomes. Astrocyte activation and migration at the site of injury provides an early defense mechanism to minimize the extent of injury by enveloping the lesion area. However, astrogliosis also contributes to the inhibitory microenvironment of CNS injury and potentiate secondary injury mechanisms, such as inflammation, oxidative stress, and glutamate excitotoxicity, which facilitate neurodegeneration in CNS pathologies. Intriguingly, reactive astrocytes are increasingly a focus in current therapeutic strategies as their activation can be modulated toward a neuroprotective and reparative phenotype. This review will discuss recent advancements in knowledge regarding the development and role of astrocytes in the healthy and pathological CNS. We will also review how astrocytes have been genetically modified to optimize their reparative potential after injury, and how they may be transdifferentiated into neurons and oligodendrocytes to promote repair after CNS injury and neurodegeneration.

Oxidative stress and impaired oligodendrocyte precursor cell differentiation in neurological disorders

Oligodendrocyte precursor cells (OPCs) account for 5% of the resident parenchymal central nervous system glial cells. OPCs are not only a back-up for the loss of oligodendrocytes that occurs due to brain injury or inflammation-induced demyelination (remyelination) but are also pivotal in plastic processes such as learning and memory (adaptive myelination). OPC differentiation into mature myelinating oligodendrocytes is controlled by a complex transcriptional network and depends on high metabolic and mitochondrial demand. Mounting evidence shows that OPC dysfunction, culminating in the lack of OPC differentiation, mediates the progression of neurodegenerative disorders such as multiple sclerosis, Alzheimer's disease and Parkinson's disease. Importantly, neurodegeneration is characterised by oxidative and carbonyl stress, which may primarily affect OPC plasticity due to the high metabolic demand and a limited antioxidant capacity associated with this cell type. The underlying mechanisms of how oxidative/carbonyl stress disrupt OPC differentiation remain enigmatic and a focus of current research efforts. This review proposes a role for oxidative/carbonyl stress in interfering with the transcriptional and metabolic changes required for OPC differentiation. In particular, oligodendrocyte (epi)genetics, cellular defence and repair responses, mitochondrial signalling and respiration, and lipid metabolism represent key mechanisms how oxidative/carbonyl stress may hamper OPC differentiation in neurodegenerative disorders. Understanding how oxidative/carbonyl stress impacts OPC function may pave the way for future OPC-targeted treatment strategies in neurodegenerative disorders.

Characterization and functional analysis of the proteins Prohibitin 1 and 2 in Trypanosoma cruzi

BACKGROUND

Chagas disease is the third most important neglected tropical disease. There is no vaccine available, and only two drugs are generally prescribed for the treatment, both of which with a wide range of side effects. Our study of T. cruzi PHBs revealed a pleiotropic function in different stages of the parasite, participating actively in the transformation of the non-infective replicative epimastigote form into metacyclic trypomastigotes and also in the multiplication of intracellular amastigotes.

METHODOLOGY/PRINCIPAL FINDINGS

To obtain and confirm our results, we applied several tools and techniques such as electron microscopy, immuno-electron microscopy, bioinformatics analysis and molecular biology. We transfected T. cruzi clones with the PHB genes, in order to overexpress the proteins and performed a CRISPR/Cas9 disruption to obtain partially silenced PHB1 parasites or completely silenced PHB2 parasites. The function of these proteins was also studied in the biology of the parasite, specifically in the transformation rate from non-infective forms to the metacyclic infective forms, and in their capacity of intracellular multiplication.

CONCLUSION/SIGNIFICANCE

This research expands our understanding of the functions of PHBs in the life cycle of the parasite. It also highlights the protective role of prohibitins against ROS and reveals that the absence of PHB2 has a lethal effect on the parasite, a fact that could support the consideration of this protein as a possible target for therapeutic action.

The value of serum uric acid as a prognostic biomarker in amyotrophic lateral sclerosis: Evidence from a meta-analysis

OBJECTIVE

To determine the value of uric acid (UA) as a prognostic biomarker for amyotrophic lateral sclerosis (ALS) using a meta-analysis of hazard ratio-based studies.

METHODS

We included data from Tokushima University (47 patients with ALS) and three previous studies (1835 patients with ALS) with a hazard ratio (HR) identified by a systematic computational search. A total of four studies and 1882 patients were enrolled in the pooled analysis. We pooled HRs of death or tracheostomy, which were estimated by a Cox proportional hazard model, using a random-effects model. Heterogeneity was assessed by Q statistic, and a p value < 0.1 was considered significant heterogeneity. Furthermore, sensitivity analysis was performed to assess the effect of each single study and the robustness of the summary effect. We evaluated publication bias by visual assessment of the funnel plot and Egger's test, and adjusted the bias using a trim-and-fill method.

RESULTS

This meta-analysis revealed that UA could be a prognostic factor for ALS (all, HR = 0.87, p < 0.001; men, HR = 0.83, p < 0.001; women, HR = 0.76, p < 0.001). The included studies were homogeneous (all, p = 0.43; men, p = 0.9; women, p = 0.49). Sensitivity analysis confirmed the robustness of these summary effects. Publication bias was detected, which was adjusted for by a trim-and-fill method. The adjusted results showed significant summary effects (all, HR = 0.88, p = 0.002; men, HR = 0.83, p < 0.001; women, HR = 0.77, p < 0.001).

CONCLUSION

The present meta-analysis suggests that the serum UA level could be a prognostic biomarker in patients with ALS. Sensitivity analyses and the trim-and-fill method supported the robustness of these results.

Tetrachlorobenzoquinone exposure triggers ferroptosis contributing to its neurotoxicity

Halogenated quinones are representative metabolites of persistent organic pollutants. Tetrachlorobenzoquinone (TCBQ) is a reactive metabolite of the widely used fungicide hexachlorobenzene (HCB) and wood preservative pentachlorophenol (PCP). Our previous studies have demonstrated that TCBQ induced neuron-like cell apoptosis in a reactive oxygen species (ROS)-dependent manner. Here, we found that TCBQ caused lipid peroxidation and cellular morphological changes including shrinked mitochondrial size, suggesting the involvement of a recently uncovered form of programmed cell death (PCD), ferroptosis. Indeed, we then identified that ferroptosis is a novel PCD driven by TCBQ, which was correlated with a decrease in glutathione peroxidase 4 (GPX4) level and iron accumulation by altering iron metabolism. Notably, nuclear factor erythroid-derived 2-like 2 (Nrf2) is a negative regulator in modulating the outcomes of ferroptosis as an adaptive cellular defense response. Nrf2 activation enhanced iron storage capacity and GPX4 activity by elevating ferritin heavy chain 1 (FTH1) expression and glutathione (GSH) level, respectively. On the contrary, Nfe2l2 (Nrf2) deficiency enhanced PC12 cells susceptibility to ferroptosis.

Uric acid aggravates myocardial ischemia-reperfusion injury via ROS/NLRP3 pyroptosis pathway

BACKGROUND

The NOD-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome activation-mediated pyroptosis pathway has been linked to myocardial ischemia-reperfusion (MI/R) injury. This study explored whether uric acid (UA) aggravates MI/R injury through NLRP3 inflammasome-mediated pyroptosis.

METHODS

In vivo, a mouse MI/R model was established by ligating the left coronary artery, and a mouse hyperuricemia model was created by intraperitoneal injection of potassium oxonate (PO). Then, the myocardial infarction (MI) size; terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL) immunofluorescence; and serum levels of lactate dehydrogenase (LDH), creatine kinase isoenzyme (CK-MB), and UA, as well as the expression level of pyroptosis-related protein and caspase-3 in heart tissues, were measured. Separately, primary mouse cardiomyocytes were cultured in vitro to create a hypoxia/reoxygenation (H/R) model. We then compared cardiomyocytes viability, TUNEL immunofluorescence, and the levels of LDH, reactive oxygen species (ROS), and pyroptosis-related protein and caspase-3 in cardiomyocytes.

RESULTS

In vivo, the MI area, levels of CK-MB and LDH, rate of cell death, and pyroptosis-related protein and the expression of caspase-3 were significantly higher in the MI/R group than in the sham group, and high UA levels worsened these changes. In vitro, cardiomyocytes viability was significantly downregulated, and the levels of ROS, LDH, pyroptosis-related protein, caspase-3, and the rate of cardiomyocyte death were significantly higher in the H/R + UA group compared with the HR group. Administration of an NLRP3 inflammasome inhibitor and ROS scavenger reversed these effects.

CONCLUSION

UA aggravates MI/R-induced activation of the NLRP3 inflammatory cascade and pyroptosis by promoting ROS generation, while inflammasome inhibitors and ROS scavengers partly reverse the injury.

Mitochondrial transformations in the aging human placenta

Mitochondria play a key role in homeostasis and are central to one of the leading hypotheses of aging, the free radical theory. Mitochondria function as a reticulated network, constantly adapting to the cellular environment through fusion (joining), biogenesis (formation of new mitochondria), and fission (separation). This adaptive response is particularly important in response to oxidative stress, cellular damage, and aging, when mitochondria are selectively removed through mitophagy, a mitochondrial equivalent of autophagy. During this complex process, mitochondria influence surrounding cell biology and organelles through the release of signaling molecules. Given that the human placenta is a unique organ having a transient and somewhat defined life span of ∼280 days, any adaption or dysfunction associated with mitochondrial physiology as a result of aging will have a dramatic impact on the health and function of both the placenta and the fetus. Additionally, a defective placenta during gestation, resulting in reduced fetal growth, has been shown to influence the development of chronic disease in later life. In this review we focus on the mitochondrial adaptions and transformations that accompany gestational length and share similarities with age-related diseases. In addition, we discuss the role of such changes in regulating placental function throughout gestation, the etiology of gestational complications, and the development of chronic diseases later in life.

Can the biological mechanisms of ageing be corrected by food supplementation. The concept of health care over sick care

"From care for the sick to care for health" implies that age-related diseases and discomforts, which impair the quality of life, should be prevented rather than treated. Healthy lifestyle and nutrition, and hormone supplementation - when needed - are of crucial importance. Food supplementation with nutraceuticals composed of vitamins, oligo-minerals, plant extracts and essential amino- and fatty acids should reduce age-related oxidative and epigenetic damage to DNA, and inhibit inflammatory and metabolic impairment. This study of the potential beneficial effects of novel nutraceuticals on the biological mechanisms of physical and mental ageing suggests these supplements may be scientifically justified. In the absence of adverse side effects and the expected favourable effect on the quality-adjusted life years, the benefit over risk ratio of nutraceutical supplementation should be positive.

A decrease in hepatitis C virus RNA to undetectable levels in chronic hepatitis C patients after PegIFNα + RVB or sofosbuvir + NS5A inhibitor treatment is associated with decreased insulin resistance and persistent oxidative stress

Oxidative stress (OS) and insulin resistance (IR) induced by hepatitis C virus (HCV) infection, are involved in the development of chronic hepatitis C (CHC) complications and progression to hepatocellular carcinoma. The aim of this study was to investigate the effect of pegylated interferon alpha (IFNα) + ribavirin (PegIFNα+RVB) or sofosbuvir + NS5A inhibitor (SOF+InNS5A) on IR and the components of OS. HCV was genotyped in 20 CHC patients grouped by treatment with either PegIFNα+RVB (n = 10) or SOF+InNS5A (n = 10). The treatment's effect on OS-induced damage to lipids (HNE-HDL), proteins (advanced glycation end products [AGEs]), and DNA (8-OHdG) as well as the concentrations of proinflammatory cytokines (IL-2, TNFα, IFNγ), ALT, AST, GSH and platelets was determined. Superoxide dismutase (SOD) and catalase activity as well as IR, determined by the HOMA1-IR index, was evaluated. The HCV genotypes (GT) found were GT1b (45%), GT1a (30%), GT2b (20%), and GT2a (5%). Viral RNA became undetectable by week 12 with SOF+InNS5A in 100% of the cases and with PegIFNα+RVB in 70% of the cases. After viral RNA became undetectable, regardless of treatment and GT, a significant increase in the platelet concentration and SOD activity was observed, whereas ALT, insulin, and IR decreased (p < 0.05). However, only for the SOF+InNS5A treated group was there an increase in oxidative damage to lipids (p < 0.017) and proteins (p < 0.05). None of the other parameters demonstrated any differences. These data confirm that OS persisted after treatment with either SOF+InNS5A or PegIFNα+RVB. IR could be considered a response biomarker to treatment with direct-acting antivirals.

Control of Reactive Oxygen Species for the Prevention of Parkinson's Disease: The Possible Application of Flavonoids

Oxidative stress reflects an imbalance between the production of reactive oxygen species (ROS) and antioxidant defense systems, and it can be associated with the pathogenesis and progression of neurodegenerative diseases such as multiple sclerosis, stroke, and Parkinson's disease (PD). The application of antioxidants, which can defend against oxidative stress, is able to detoxify the reactive intermediates and prevent neurodegeneration resulting from excessive ROS production. There are many reports showing that numerous flavonoids, a large group of natural phenolic compounds, can act as antioxidants and the application of flavonoids has beneficial effects in the adult brain. For instance, it is well known that the long-term consumption of the green tea-derived flavonoids catechin and epigallocatechin gallate (EGCG) can attenuate the onset of PD. Also, flavonoids such as ampelopsin and pinocembrin can inhibit mitochondrial dysfunction and neuronal death through the regulation of gene expression of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. Additionally, it is well established that many flavonoids exhibit anti-apoptosis and anti-inflammatory effects through cellular signaling pathways, such as those involving (ERK), glycogen synthase kinase-3β (GSK-3β), and (Akt), resulting in neuroprotection. In this review article, we have described the oxidative stress involved in PD and explained the therapeutic potential of flavonoids to protect the nigrostriatal DA system, which may be useful to prevent PD.

Mapping the Neuroanatomy of ABHD16A, ABHD12, and Lysophosphatidylserines Provides New Insights into the Pathophysiology of the Human Neurological Disorder PHARC

Lysophosphatidylserine (lyso-PS), a lysophospholipid derived from phosphatidylserine (PS), has emerged as a potent signaling lipid in mammalian physiology. In vivo, the metabolic serine hydrolases ABHD16A and ABHD12 are major lipases that biosynthesize and degrade lyso-PS, respectively. Of biomedical relevance, deleterious mutations to ABHD12 cause accumulation of lyso-PS in the brain, and this deregulated lyso-PS metabolism leads to the human genetic neurological disorder PHARC (polyneuropathy, hearing loss, ataxia, retinitis pigmentosa, and cataract). While the roles of ABHD16A and ABHD12 in lyso-PS metabolism in the mammalian brain are well established, the anatomical and (sub)cellular localizations of both lipases and the functional cross-talk between them with respect to regulating lyso-PS lipids remain under investigated. Here, using subcellular organelle fractionation, biochemical assays, and immunofluorescence-based high-resolution microscopy, we show that the PS lipase ABHD16A is an endoplasmic reticulum-localized enzyme, an organelle intricately regulating cellular PS levels. In addition, leveraging immunohistochemical analysis using genetic ABHD16A and ABHD12 knockout mice as important controls, we map the anatomical distribution of both of these lipases in tandem in the murine brain and show for the first time the distinct localization of these lipases to different regions and cells of the cerebellum. We complement the aforementioned immunohistochemical studies by quantitatively measuring lyso-PS concentrations in various brain regions using mass spectrometry and find that the cerebellar lyso-PS levels are most affected by deletion of ABHD16A (decreased) or ABHD12 (increased). Taken together, our studies provide new insights into lyso-PS signaling in the cerebellum, the most atrophic brain region in human PHARC subjects.

The effect and mechanism of 19S proteasome PSMD11/Rpn6 subunit in D-Galactose induced mimetic aging models

Regulating proteasome activity is a potent therapeutic aspect of age-related hearing loss, which has been proven to protect neurons from age-related damaging. PSMD11, subunit of the 19S proteasome regulatory particle, is known to mainly up-regulate proteasome activity and prolong aging. However, the mechanism of PSMD11 in age-related hearing loss has not been deeply explored. In the present study, we explore the function and mechanism of PSMD11 protecting neurons in d-Galactose (D-Gal) mimetic aging models. Age-related pathologies were detected by Taq-PCR, ABR, Transmission electron microscopy, toluidine blue and β-galactosidase staining. The relative expressions of the proteins were explored by Western blotting, oxyblot, immunoprecipitation and immunofluorescence. Flow cytometry was used to manifest the oxidative state. We discovered that proteasome activity was impaired with aging, and that ROS and toxic protein accumulated in D-Gal induced aging models. PSMD11 changed with aging, and was associated with the metabolism of proteasome activity in the D-Gal treated models. Moreover, the knockdown or overexpression of PSMD11 was sufficient to change the oxidative state caused by D-Gal. Our results also demonstrated that PSMD11 could bond to AMPKα1/2 in the auditory cortex and PC12 cells, and AMPKα2 but not AMPKα1 was efficient to regulate the function of PSMD11. Deeper insights into the mechanisms of regulating PSMD11 for the anti-aging process are needed, and may offer novel therapeutic methods for central presbycusis.

Glycofullerenes Inhibit Particulate Matter Induced Inflammation and Loss of Barrier Proteins in HaCaT Human Keratinocytes

Exposure to particulate matter (PM) has been linked to pulmonary and cardiovascular dysfunctions, as well as skin diseases, etc. PM impairs the skin barrier functions and is also involved in the initiation or exacerbation of skin inflammation, which is linked to the activation of reactive oxygen species (ROS) pathways. Fullerene is a single C₆₀ molecule which has been reported to act as a good radical scavenger. However, its poor water solubility limits its biological applications. The glyco-modification of fullerenes increases their water solubility and anti-bacterial and anti-virus functions. However, it is still unclear whether it affects their anti-inflammatory function against PM-induced skin diseases. Hence, glycofullerenes were synthesized to investigate their effects on PM-exposed HaCaT human keratinocytes. Our results showed that glycofullerenes could reduce the rate of PM-induced apoptosis and ROS production, as well as decrease the expression of downstream mitogen-activated protein kinase and Akt pathways. Moreover, PM-induced increases in inflammatory-related signals, such as cyclooxygenase-2, heme oxygenase-1, and prostaglandin E2, were also suppressed by glycofullerenes. Notably, our results suggested that PM-induced impairment of skin barrier proteins, such as filaggrin, involucrin, repetin, and loricrin, could be reduced by pre-treatment with glycofullerenes. The results of this study indicate that glycofullerenes could be potential candidates for treatments against PM-induced skin diseases and that they exert their protective effects via ROS scavenging, anti-inflammation, and maintenance of the expression of barrier proteins.

Exercise, redox system and neurodegenerative diseases

Regular exercise induces a wide range of redox system-associated molecular adaptive responses to the nervous system. The intermittent induction of reactive oxygen species (ROS) during acute exercise sessions and the related upregulation of antioxidant/repair and housekeeping systems are associated with improved physiological function. Exercise-induced proliferation and differentiation of neuronal stem cells are ROS dependent processes. The increased production of brain derived neurotrophic factor (BDNF) and the regulation by regular exercise are dependent upon redox sensitive pathways. ROS are causative and associative factors of neurodegenerative diseases and regular exercise provides significant neuroprotective effects against Alzheimer's disease, Parkinson's disease, and hypoxia/reperfusion related disorders. Regular exercise regulates redox homeostasis in the brain with complex multi-level molecular pathways.

Melatonin mitigates hippocampal and cognitive impairments caused by prenatal irradiation

Formation of new neurons and glial cells in the brain is taking place in mammals not only during prenatal embryogenesis but also during adult life. As an enhancer of oxidative stress, ionizing radiation represents a potent inhibitor of neurogenesis and gliogenesis in the brain. It is known that the pineal hormone melatonin is a potent free radical scavenger and counteracts inflammation and apoptosis in brain injuries. The aim of our study was to establish the effects of melatonin on cells in the hippocampus and selected forms of behaviour in prenatally irradiated rats. The male progeny of irradiated (1 Gy of gamma rays; n = 38) and sham-irradiated mothers (n = 19), aged 3 weeks or 2 months, were used in the experiment. Melatonin was administered daily in drinking water (4 mg/kg b. w.) to a subset of animals from each age group. Prenatal irradiation markedly suppressed proliferative activity in the dentate gyrus in both age groups. Melatonin significantly increased the number of proliferative BrdU-positive cells in hilus of young irradiated animals, and the number of mature NeuN-positive neurons in hilus and granular cell layer of the dentate gyrus in these rats and in CA1 region of adult irradiated rats. Moreover, melatonin significantly improved the spatial memory impaired by irradiation, assessed in Morris water maze. A significant correlation between the number of proliferative cells and cognitive performances was found, too. Our study indicates that melatonin may decrease the loss of hippocampal neurons in the CA1 region and improve cognitive abilities after irradiation.

Antioxidant Alternatives in the Treatment of Amyotrophic Lateral Sclerosis: A Comprehensive Review

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that produces a selective loss of the motor neurons of the spinal cord, brain stem and motor cortex. Oxidative stress (OS) associated with mitochondrial dysfunction and the deterioration of the electron transport chain has been shown to be a factor that contributes to neurodegeneration and plays a potential role in the pathogenesis of ALS. The regions of the central nervous system affected have high levels of reactive oxygen species (ROS) and reduced antioxidant defenses. Scientific studies propose treatment with antioxidants to combat the characteristic OS and the regeneration of nicotinamide adenine dinucleotide (NAD+) levels by the use of precursors. This review examines the possible roles of nicotinamide riboside and pterostilbene as therapeutic strategies in ALS.

Vitamin C attenuates memory loss induced by post-traumatic stress like behavior in a rat model

Oxidative stress is associated with neuronal damage in many brain regions including the hippocampus; an area in the brain responsible of memory processing. Oxidative stress is also linked with many psychiatric conditions including post-traumatic stress disorder (PTSD). PTSD is triggered by traumatic experience and many PTSD patients show signs of memory impairment. Vitamin C is a water-soluble vitamin with antioxidant properties. Herein, we hypothesized that memory impairment observed during PTSD could be a result of oxidative stress in hippocampal tissues and that prophylactic vitamin C administration may reduce oxidative stress in the hippocampus and prevent memory impairment. The above hypothesis was tested in a rat model where PTSD-like behavior was induced through single prolonged stress (SPS). Short and long-term memory was tested using a radial arm water maze (RAWM). We found that SPS induced a significant increase in the oxidized glutathione levels of the hippocampus. This reduction was accompanied with a significant decrease in glutathione peroxidase and catalase enzyme activity, and a significant increase in lipid peroxidation. Intriguingly, vitamin C administration successfully attenuated memory impairment and all of the changes observed in oxidative stress markers. Our findings demonstrate that vitamin C could prevent oxidative stress and memory impairment induced by SPS model of PTSD-like behavior in rat.

Iron, Ferritin, Hereditary Ferritinopathy, and Neurodegeneration

Cellular growth, function, and protection require proper iron management, and ferritin plays a crucial role as the major iron sequestration and storage protein. Ferritin is a 24 subunit spherical shell protein composed of both light (FTL) and heavy chain (FTH1) subunits, possessing complimentary iron-handling functions and forming three-fold and four-fold pores. Iron uptake through the three-fold pores is well-defined, but the unloading process somewhat less and generally focuses on lysosomal ferritin degradation although it may have an additional, energetically efficient pore mechanism. Hereditary Ferritinopathy (HF) or neuroferritinopathy is an autosomal dominant neurodegenerative disease caused by mutations in the FTL C-terminal sequence, which in turn cause disorder and unraveling at the four-fold pores allowing iron leakage and enhanced formation of toxic, improperly coordinated iron (ICI). Histopathologically, HF is characterized by iron deposition and formation of ferritin inclusion bodies (IBs) as the cells overexpress ferritin in an attempt to address iron accumulation while lacking the ability to clear ferritin and its aggregates. Overexpression and IB formation tax cells materially and energetically, i.e., their synthesis and disposal systems, and may hinder cellular transport and other spatially dependent functions. ICI causes cellular damage to proteins and lipids through reactive oxygen species (ROS) formation because of high levels of brain oxygen, reductants and metabolism, taxing cellular repair. Iron can cause protein aggregation both indirectly by ROS-induced protein modification and destabilization, and directly as with mutant ferritin through C-terminal bridging. Iron release and ferritin degradation are also linked to cellular misfunction through ferritinophagy, which can release sufficient iron to initiate the unique programmed cell death process ferroptosis causing ROS formation and lipid peroxidation. But IB buildup suggests suppressed ferritinophagy, with elevated iron from four-fold pore leakage together with ROS damage and stress leading to a long-term ferroptotic-like state in HF. Several of these processes have parallels in cell line and mouse models. This review addresses the roles of ferritin structure and function within the above-mentioned framework, as they relate to HF and associated disorders characterized by abnormal iron accumulation, protein aggregation, oxidative damage, and the resulting contributions to cumulative cellular stress and death.

Comparison of the Biological Impact of UVA and UVB upon the Skin with Functional Proteomics and Immunohistochemistry

The skin provides protection against external stimuli; however, solar radiation, including ultraviolet A (UVA) and ultraviolet B (UVB), can result in profound influences on skin structure and function, which eventually impairs its molecular characteristics and normal physiology. In the current study, we performed proteome tools combined with an immunohistological approach on nude mouse skin to evaluate the adverse responses elicited by UVA and UVB irradiation, respectively. Our findings indicated that UVA significantly promotes oxidative damage in DNA, the breakdown of collagen fiber in the dermis, and the apoptosis of fibroblasts, which leads to inflammation. Meanwhile, UVB administration was found to enhance the carbonylation of various proteins and the proliferation of keratinocyte. Particularly, raspberry extract, which has been confirmed to have antioxidative efficacy, could effectively attenuate ultraviolet (UV) radiation-caused cell death. Network analysis also implied that UVA and UVB induce quite different responses, and that UVA results in cell death as well as inflammation mediated by caspase-3 and activator protein 1/nuclear factor kappa-light-chain-enhancer of activated B cells (AP-1/NF-κB), while UVB predominantly increases the risk of skin carcinogenesis involved with oncogenes such as p53 and c-Myc. Taken together, functional proteomics coordinated with histological experiments could allow for a high-throughput study to explore the alterations of crucial proteins and molecules linked to skin impacts subjected to UVA and UVB exposure.

Water-Soluble Fullerenol C60(OH)36 toward Effective Anti-Air Pollution Induced by Urban Particulate Matter in HaCaT Cell

Particulate matter (PM), a widespread air pollutant, consists of a complex mixture of solid and liquid particles suspended in air. Many diseases have been linked to PM exposure, which induces an imbalance in reactive oxygen species (ROS) generated in cells, and might result in skin diseases (such as aging and atopic dermatitis). New techniques involving nanomedicine and nano-delivery systems are being rapidly developed in the medicinal field. Fullerene, a kind of nanomaterial, acts as a super radical scavenger. Lower water solubility levels limit the bio-applications of fullerene. Hence, to improve the water solubility of fullerene, while retaining its radical scavenger functions, a fullerene derivative, fullerenol C₆₀(OH)₃₆, was synthesized, to examine its biofunctions in PM-exposed human keratinocyte (HaCaT) cells. The PM-induced increase in ROS levels and expression of phosphorylated mitogen-activated protein kinase and Akt could be inhibited via fullerenol pre-treatment. Furthermore, the expression of inflammation-related proteins, cyclooxygenase-2, heme oxygenase-1, and prostaglandin E2 was also suppressed. Fullerenol could preserve the impaired state of skin barrier proteins (filaggrin, involucrin, repetin, and loricrin), which was attributable to PM exposure. These results suggest that fullerenol could act against PM-induced cytotoxicity via ROS scavenging and anti-inflammatory mechanisms, and the maintenance of expression of barrier proteins, and is a potential candidate compound for the treatment of skin diseases.

Ginsenoside Rg1 prevents acetaminophen-induced oxidative stress and apoptosis via Nrf2/ARE signaling pathway

Inappropriate use of acetaminophen (APAP) can lead to morbidity and mortality secondary to hepatic necrosis. Ginsenoside Rg1 is a major active ingredient in processed Panax ginseng, which is proved to elicit biological effects. We hypothesized the beneficial effect of Rg1 on APAP-mediated hepatotoxicity was through Nrf2/ARE pathway. The study was conducted in cells and mice, comparing the actions of Rg1. Rg1 significantly improved cell survival rates and promoted the expression of antioxidant proteins. Meanwhile, Rg1 reduced the excessive ROS and the occurrence of cell apoptosis, which were related to Nrf2/ARE pathway. Expression of Nrf2 has a certain cell specificity.

Do the Number of Cigarettes Smokes per Day Contribute to the Incident of Malignant Cancer?

Background:

The incident of malignant cancer due to smoking habit becomes a public health problem especially in the developing countries. Active smokers neglect to stop smoking even though various studies proved that smoking increases the risk of cancer. While, previous studies have assessed the incident risk of cancer but have not performed the validity of the measurement. The aim of this study is to know the number of cigarettes that contribute to the incidence of malignant cancer.

Methods:

A study with retrospective cohort design has been conducted by using a set of public data of Indonesia Family Life Survey (IFLS) in 2007 and 2014. All active smokers (n= 748) who were in good health condition in 2007, were traced in 2014 and then being diagnosed with cancer with considering age, gender, healthy eating habit, and regular physical activity. Data has been analysed by using logistic regression by performing Adjusted Risk Ratio (ARR) and the result of validity measurement.

Results:

The incident of malignant cancer in 2014 were skin, liver, stomach and oral cavity. Smoking 21-30 per day in 2007 were significantly increased risk of having malignant cancer in 2014 at ARR: 6.88; SE: 6.13 with the accuracy were 93.8%. The risk and accuracy were higher if smoke >30 cigarettes per day (ARR: 7.523;SE: 7.019; accuracy 95.5%). This study also found that the risk of cancer was significantly increase with age (99% CI; ARR: 1.065; SE: 0.026).

Conclusions:

Cigarette smoking behaviour increased the risk any types incident of cancer. Total number >20 cigarettes smoked per day contributes to the incidence of malignant cancer.

The Neuroprotective Effect of Conditioned Medium from Human Adipose-Derived Mesenchymal Stem Cells is Impaired by N-acetyl Cysteine Supplementation

Oxidative stress is a common feature in neurodegenerative diseases associated with neuroinflammation, and therefore, has been proposed as a key target for novel therapies for these diseases. Recently, adipose-derived stem cell (ASC)-based cell therapy has emerged as a novel strategy for neuroprotection. In this study, we evaluate the therapeutic role of ASC-conditioned medium (ASC-CM) against H₂O₂-induced neurotoxicity in a new in vitro model of ec23/brain-derived neurotrophic factor (BDNF)-differentiated human SH-SY5Y neuron-like cells (SH-SY5Yd). In the presence of ASC-CM, stressed SH-SY5Yd cells recover normal axonal morphology (with an almost complete absence of H₂O₂-induced axonal beading), electrophysiological features, and cell viability. This beneficial effect of ASC-CM was associated with its antioxidant capacity and the presence of growth factors, namely, BDNF, glial cell line-derived neurotrophic factor, and transforming growth factor β1. Moreover, the neuroprotective effect of ASC-CM was very similar to that obtained from treatment with BDNF, an essential factor for SH-SY5Yd cell survival. Importantly, we also found that the addition of the antioxidant agent N-acetyl cysteine to ASC-CM abolished its restorative effect; this was associated with a strong reduction in reactive oxygen species (ROS), in contrast to the moderate decrease in ROS produced by ASC-CM alone. These results suggest that neuronal restorative effect of ASC-CM is associated with not only the release of essential neurotrophic factors, but also the maintenance of an appropriate redox state to preserve neuronal function.