Linkage of inflammation and oxidative stress via release of glutathionylated peroxiredoxin-2, which acts as a danger signal

Redox regulation of macrophages

Redox signaling, a mode of signal transduction that involves the transfer of electrons from a nucleophilic to electrophilic molecule, has emerged as an essential regulator of inflammatory macrophages. Redox reactions are driven by reactive oxygen/nitrogen species (ROS and RNS) and redox-sensitive metabolites such as fumarate and itaconate, which can post-translationally modify specific cysteine residues in target proteins. In the past decade our understanding of how ROS, RNS, and redox-sensitive metabolites control macrophage function has expanded dramatically. In this review, we discuss the latest evidence of how ROS, RNS, and metabolites regulate macrophage function and how this is dysregulated with disease. We highlight the key tools to assess redox signaling and important questions that remain.

Cladodes of Opuntia ficus-indica (L.) Mill. Possess Important Beneficial Properties Dependent on Their Different Stages of Maturity

Opuntia ficus-indica (L.) Mill. belongs to the Cactaceae family and the genus Opuntia; it is a succulent plant that adapts to extreme climatic conditions. The aerial part of the plant consists of the cladodes, morphological changes of branches that appear green, are covered with thorns, and are essential to reduce excessive perspiration of water. The composition of cladodes is very varied, and the main constituents are water, fibers, polysaccharides, proteins, fatty acids, vitamins, sterols, minerals, and polyphenols. Polyphenols are responsible for many beneficial activities for human health, such as antioxidant, anti-inflammatory, anticancer, and nutritional properties. The purpose of this manuscript was to compare the properties of cladodes belonging to the same plant but with different stages of maturity. Relative extracts were tested both in vitro and on a cell line and antioxidant and anti-apoptotic properties were found. The antioxidant activity was tested by the Oxygen Radical Absorbance Capacity (ORAC) test, the 1,1-diphenyl-2-picrylhydrazil (DPPH) test, and the measurement of cellular accumulation of reactive oxygen species (ROS). Anti-apoptotic activity was evaluated by the annexin/PI assay and measurement of caspases 9 and 3 expression. The results obtained showed that the extracts considered possess antioxidant and anti-apoptotic properties. However, the different stages of maturity of cladodes are essential for the performance of both functions. In addition, important variations were made in the dissolution of the extracts that brought greater safety in their use. In conclusion, this manuscript provides further information on cladodes of Opuntia ficus-indica, which can be used as adjuvants in many human pathologies.

Potential mechanisms of formononetin against inflammation and oxidative stress: a review

Formononetin (FMNT) is a secondary metabolite of flavonoids abundant in legumes and graminaceous plants such as Astragalus mongholicus Bunge [Fabaceae; Astragali radix] and Avena sativa L. [Poaceae]. Astragalus is traditionally used in Asia countries such as China, Korea and Mongolia to treat inflammatory diseases, immune disorders and cancers. In recent years, inflammation and oxidative stress have been found to be associated with many diseases. A large number of pharmacological studies have shown that FMNT, an important bioactive metabolite of Astragalus, has a profoundly anti-inflammatory and antioxidant potential. This review focuses on providing comprehensive and up-to-date findings on the efficacy of the molecular targets and mechanisms involve of FMNT and its derivatives against inflammation and oxidative stress in both in vitro and in vivo. Relevant literature on FMNT against inflammation and oxidative stress between 2013 and 2023 were analyzed. FMNT has antioxidant and anti-inflammatory potential and shows mild or no toxicity in various diseases. Moreover, in the medical field, FMNT has shown potential in the prevention and treatment of cancers, neurological diseases, fibrotic diseases, allergic diseases, metabolic diseases, cardiovascular diseases, gastrointestinal diseases and autoimmune diseases. Thus, it is expected to be utilized in more products in the medical, food and cosmetic industries in the future.

A Prospective Study of the Association Between Plasma Calprotectin Levels and New-Onset CKD in the General Population

Introduction

Systemic inflammation has been associated with chronic kidney disease (CKD). In this study, we aimed to investigate a potential association between the plasma biomarker of inflammation calprotectin and new-onset CKD in a population-based cohort study.

Methods

Individuals without CKD at baseline (n = 4662) who participated in the Prevention of REnal and Vascular ENd-stage Disease (PREVEND) prospective population-based cohort study in the Netherlands were included. Baseline plasma calprotectin levels were assessed in samples that had been stored at -80 °C. Occurrence of new-onset CKD was defined as a composite outcome of an estimated glomerular filtration rate (eGFR) <60 ml/min per 1.73 m2, urinary albumin excretion (UAE) >30 mg/24h, or both.

Results

Baseline median (interquartile range) plasma calprotectin levels were 0.49 (0.35-0.68) mg/l and baseline median eGFR was 95.9 (interquartile range: 85.0-105.7) ml/min per 1.73 m2. After median follow-up of 8.3 (7.8-8.9) years, 467 participants developed new-onset CKD. Baseline plasma calprotectin levels were significantly associated with an increased risk of new-onset CKD (hazard ratio [HR] per doubling 1.28 [95% confidence interval, CI: 1.14-1.44], P < 0.001), independent of potentially confounding factors (HR 1.14 [95% CI: 1.01-1.29], P = 0.034), except for baseline high-sensitive C-reactive protein (hs-CRP) (HR 1.05 [0.91-1.21], P = 0.494). In secondary analyses, the association between plasma calprotectin and occurrence of UAE >30 mg/24h remained significant (HR 1.17 [1.02-1.34], P = 0.027), but not significantly so for the incidence of eGFR <60 ml/min per 1.73 m2 as individual outcome (HR 1.15 [0.92-1.43], P = 0.218).

Conclusion

Higher plasma calprotectin levels are associated with an increased risk of developing CKD in the general population. This association is mitigated after adjustment for hs-CRP, and more pronounced with new-onset CKD defined by UAE.

Computational models as catalysts for investigating redoxin systems

Thioredoxin, glutaredoxin and peroxiredoxin systems play central roles in redox regulation, signaling and metabolism in cells. In these systems, reducing equivalents from NAD(P)H are transferred by coupled thiol-disulfide exchange reactions to redoxins which then reduce a wide array of targets. However, the characterization of redoxin activity has been unclear, with redoxins regarded as enzymes in some studies and redox metabolites in others. Consequently, redoxin activities have been quantified by enzyme kinetic parameters in vitro, and redox potentials or redox ratios within cells. By analyzing all the reactions within these systems, computational models showed that many kinetic properties attributed to redoxins were due to system-level effects. Models of cellular redoxin networks have also been used to estimate intracellular hydrogen peroxide levels, analyze redox signaling and couple omic and kinetic data to understand the regulation of these networks in disease. Computational modeling has emerged as a powerful complementary tool to traditional redoxin enzyme kinetic and cellular assays that integrates data from a number of sources into a single quantitative framework to accelerate the analysis of redoxin systems.

Choroid plexus immune cell response in murine hydrocephalus induced by intraventricular hemorrhage

BACKGROUND

Intraventricular hemorrhage (IVH) and associated hydrocephalus are significant complications of intracerebral and subarachnoid hemorrhage. Despite proximity to IVH, the immune cell response at the choroid plexus (ChP) has been relatively understudied. This study employs CX3CR-1GFP mice, which marks multiple immune cell populations, and immunohistochemistry to outline that response.

METHODS

This study had four parts all examining male adult CX3CR-1GFP mice. Part 1 examined naïve mice. In part 2, mice received an injection 30 µl of autologous blood into right ventricle and were euthanized at 24 h. In part 3, mice underwent intraventricular injection of saline, iron or peroxiredoxin 2 (Prx-2) and were euthanized at 24 h. In part 4, mice received intraventricular iron injection and were treated with either control or clodronate liposomes and were euthanized at 24 h. All mice underwent magnetic resonance imaging to quantify ventricular volume. The ChP immune cell response was examined by combining analysis of GFP(+) immune cells and immunofluorescence staining.

RESULTS

IVH and intraventricular iron or Prx-2 injection in CX3CR-1GFP mice all induced ventriculomegaly and activation of ChP immune cells. There were very marked increases in the numbers of ChP epiplexus macrophages, T lymphocytes and neutrophils. Co-injection of clodronate liposomes with iron reduced the ventriculomegaly which was associated with fewer epiplexus and stromal macrophages but not reduced T lymphocytes and neutrophils.

CONCLUSION

There is a marked immune cell response at the ChP in IVH involving epiplexus cells, T lymphocytes and neutrophils. The blood components iron and Prx-2 may play a role in eliciting that response. Reduction of ChP macrophages with clodronate liposomes reduced iron-induced ventriculomegaly suggesting that ChP macrophages may be a promising therapeutic target for managing IVH-induced hydrocephalus.

Comparative analysis of miRNAs and mRNAs in large yellow croaker head kidney cells (LYCK) provided novel insights into the redox regulation of fish

Reactive oxygen species (ROS) over-production and oxidative stress resulted from climate change and environmental pollution seriously endangered global fish populations and healthy development of marine aquaculture. Peroxiredoxins (Prxs), a highly conserved family of thiol-specific antioxidants, can mitigate ROS and protect cells from oxidative stress. We previously demonstrated that large yellow croaker PrxIV (LcPrxIV) could not only regulate the pro-inflammatory responses, but also scavenge ROS. However, the underlying mechanism how LcPrxIV regulated immune response and redox homeostasis remains unknown. MicroRNAs (miRNAs) are non-coding RNAs that play important roles in the regulation of various biological processes. In this study, mRNA and miRNA expression profiles from LYCK-pcDNA3.1 and LYCK-PrxIV cells, with or without oxidative stress stimulated by H2O2 were evaluated using high-throughput sequencing. A series of differentially expressed miRNAs (DEMs) and differentially expressed genes (DEGs), as well as DEM-DEG pairs were identified from each two-group comparison, respectively. GO and KEGG functional analyses indicated that most significant DEGs were associated with signaling pathways related to oxidative stress and immune response. Subsequent DEM-DEG interaction analysis revealed that miR-731 and miR-1388 may be involved in both redox regulation and immune response via synergistic effect with LcPrxIV. Interestingly, miR-731 could regulate the expression of different down-stream DEGs under different stimulations of LcPrxIV over-expression, H2O2, or both. Moreover, miR-731 could cause the DEG, γ-glutamyl hydrolase (GGH), to be expressed in opposite ways under different stimulations. On the other hand, the expression of miR-1388 could be negatively or positively regulated under the stimulation of LcPrxIV over-expression with or without oxidative stress, thus regulating gene expression of different mRNAs. Based on these results, we speculate that LcPrxIV may participate in immune response or redox regulation by regulating the expression of different down-stream genes through controlling the expression level of a certain miRNA or by regulating the varieties of expressed miRNAs.

Effect of Adrenocorticotropic Hormone Stimulation on Ischemiamodified Albumin Levels in vivo

Objective

Ischemia-modified albumin (IMA) formation is associated with increased reactive oxygen species (ROS) production, while increased cortisol leads to decreased ROS levels. We aimed to evaluate the effect of adrenocorticotropic hormone (ACTH) stimulation on IMA levels and whether the effect was dose-dependent or not.

Methods

A total of 99 subjects with normal ACTH test results were included in the study. Of these, 80 had standard-dose ACTH test while 19 had low-dose ACTH test. Blood samples were collected to determine cortisol and IMA levels; at minutes 0, 30, and 60 following the standard-dose ACTH test and at minutes 0 and 30 following the low-dose ACTH test.

Results

IMA levels decreased significantly within 30 minutes and the decrease continued up to the sixtieth minute (p=0.002) after standard-dose ACTH stimulation. After ACTH stimulation, a weak negative correlation was found between peak cortisol and IMA levels at the thirtieth minute (r=0.233, p=0.02). There was no significant difference in IMA levels after low-dose ACTH stimulation, despite an increase in cortisol (p=0.161).

Conclusion

IMA levels decreased rapidly after standard-dose ACTH stimulation, while a decrease in IMA levels was not observed after low-dose ACTH stimulation. The lack of decrease in IMA levels after low-dose ACTH stimulation suggests a possible dose-dependent relationship between ACTH and IMA. The moderate increase in cortisol with no reduction in IMA levels after low-dose ACTH stimulation and the weak correlation between peak cortisol and 30-minute IMA levels after standard-dose ACTH stimulation suggest that ACTH may have a direct effect on IMA.

Yellow fever virus infection in human hepatocyte cells triggers an imbalance in redox homeostasis with increased reactive oxygen species production, oxidative stress, and decreased antioxidant enzymes

Yellow fever (YF) presents a wide spectrum of severity, with clinical manifestations in humans ranging from febrile and self-limited to fatal cases. Although YF is an old disease for which an effective and safe vaccine exists, little is known about the viral- and host-specific mechanisms that contribute to liver pathology. Several studies have demonstrated that oxidative stress triggered by viral infections contributes to pathogenesis. We evaluated whether yellow fever virus (YFV), when infecting human hepatocytes cells, could trigger an imbalance in redox homeostasis, culminating in oxidative stress. YFV infection resulted in a significant increase in reactive oxygen species (ROS) levels from 2 to 4 days post infection (dpi). When measuring oxidative parameters at 4 dpi, YFV infection caused oxidative damage to lipids, proteins, and DNA, evidenced by an increase in lipid peroxidation/8-isoprostane, carbonyl protein, and 8-hydroxy-2'-deoxyguanosine, respectively. Furthermore, there was a significant reduction in the activity of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx), in addition to a reduction in the ratio of reduced to oxidized glutathione (GSH/GSSG), indicating a pro-oxidant environment. However, no changes were observed in the enzymatic activity of the enzyme catalase (CAT) or in the gene expression of SOD isoforms (1/2/3), CAT, or GPx. Therefore, our results show that YFV infection generates an imbalance in redox homeostasis, with the overproduction of ROS and depletion of antioxidant enzymes, which induces oxidative damage to cellular constituents. Moreover, as it has been demonstrated that oxidative stress is a conspicuous event in YFV infection, therapeutic strategies based on antioxidant biopharmaceuticals may be new targets for the treatment of YF.

Implications and progression of peroxiredoxin 2 (PRDX2) in various human diseases

Peroxiredoxin 2 (PRDX2), a characteristic 2-Cys enzyme is one of the foremost effective scavenger proteins against reactive oxygen species (ROS) and hydrogen peroxide (H2O2) defending cells against oxidative stress. Dysregulation of this antioxidant raises the quantity of ROS and oxidative stress implicated in several diseases. PRDX2 lowers the generation of ROS that takes part in controlling several signalling pathways occurring in neurons, protecting them from stress caused by oxidation and an inflammatory harm. Depending on the aetiological variables, the kind of cancer, and the stage of tumour development, PRDX2 may behave either as an onco-suppressor or a promoter. However, overexpression of PRDX2 may be linked to the development of numerous cancers, including those of the colon, cervix, breast, and prostate. PRDX2 also plays a beneficial effect in inflammatory diseases. PRDX2 being a thiol-specific peroxidase, is known to control proinflammatory reactions. The spilling of PRDX2, on the other hand, accelerates cognitive impairment following a stroke by triggering an inflammatory reflex. PRDX2 expression patterns in vascular cells tend to be crucial to its involvement in cardiovascular diseases. In vascular smooth muscle cells, if the protein tyrosine phosphatase is restricted, PRDX2 could avoid the neointimal thickening which relies on platelet derived growth factor (PDGF), a vital component of vascular remodelling. A proper PRDX2 balance is therefore crucial. The imbalance causes a number of illnesses, including cancers, inflammatory diseases, cardiovascular ailments, and neurological and neurodegenerative problems which are discussed in this review.

Health Effects of Electrolyzed Hydrogen Water for the Metabolic Syndrome and Pre-Metabolic Syndrome: A 3-Month Randomized Controlled Trial and Subsequent Analyses

We studied the effect of three months' use of electrolyzed hydrogen water (EHW, Electrolyzed Hydrogen Water conditioner produced by Nihon Trim Co., Ltd.) on metabolic and pre-metabolic syndrome groups. This research was carried out jointly by Susaki City; Nihon Trim Co., Ltd.; and Kochi University as part of a local revitalization project with health as a keyword. A randomized, placebo-controlled, double-blind, parallel-group trial was conducted to evaluate the clinical impact of EHW on participants who suffered from metabolic syndrome or pre-metabolic syndrome. EHW was produced via electrolysis using a commercially available apparatus (Nihon Trim Co., Ltd., Osaka, Japan). During exercise, oxidative stress increases, and active oxygen species increase. In this study, we examined 181 subjects with metabolic syndrome or pre-metabolic syndrome. Among the group that drank EHW for 3 months, those who also engaged in a high level of physical activity showed a significant difference in waist circumference reduction. Although no significant difference was observed, several positive results were found in the participants who engaged in a high level of physical activity. Urinary 8-OHdG, urinary nitrotyrosine, HbA1c, and blood glucose levels increased in the filtered water (FW) group but decreased in the EHW group. High-sensitivity CRP increased less in the EHW group. 8-Isoprostane decreased more in the EHW group. In subgroup analysis, the EHW group showed a significantly greater reduction in waist circumference than the FW group only when controlled for high physical activity. Based on the result, we suggest that, among participants in the study who suffered from metabolic syndrome and pre-metabolic syndrome in which the level of active oxygen species is said to be higher than in healthy subjects, the group that consumed EHW and also engaged in a high level of physical activity experienced a suppressed or reduced increase in active oxygen species.

Plasma Calprotectin Levels Associate With New-Onset Hypertension in the General Population: A Prospective Cohort Study

BACKGROUND

Low-grade systemic inflammation is a relevant pathogenic mechanism underlying the development of hypertension. In this study, we hypothesized that plasma calprotectin levels, as a biomarker of neutrophil-mediated inflammation, is associated with developing new-onset hypertension in the general population.

METHODS AND RESULTS

Plasma calprotectin levels were determined in 3524 participants who participated in the PREVEND (Prevention of Renal and Vascular End-Stage Disease) study, a prospective population-based cohort study. Plasma calprotectin levels were studied for associations with the risk of new-onset hypertension, defined as systolic blood pressure of at least 140 mm Hg, diastolic blood pressure of at least 90 mm Hg, or the first recorded use of antihypertensives. Participants with hypertension at baseline were excluded. Median plasma calprotectin levels were 0.48 (0.34-0.66) mg/L, and median systolic blood pressure was 117 (109-126) mm Hg. Plasma calprotectin levels were significantly associated with the risk of new-onset hypertension (hazard ratio [HR], per doubling 1.30 [95% CI, 1.21-1.41]; P<0.001), also after adjustment for age and sex (HR, 1.26 [95% CI, 1.16-1.37]; P<0.001), but not after additional adjustment for potentially confounding factors, including baseline systolic blood pressure (HR, 1.00 [95% CI, 0.90-1.11]; P=0.996). Stratified analyses showed significant effect modification by sex (Pinteraction=0.023) and urinary albumin excretion (Pinteraction=0.004), with higher HRs in men (compared with women) and in individuals with higher urinary albumin excretion (>9.3 mg per 24 hours) compared with lower urinary albumin excretion (≤9.3 mg per 24 hours).

CONCLUSIONS

Higher plasma calprotectin levels are associated with an increased risk of new-onset hypertension in the general population. This association is dependent on baseline systolic blood pressure and is particularly prominent in men compared with women.

The Wild Carrot (Daucus carota): A Phytochemical and Pharmacological Review

Daucus carota L., a member of the Apiaceae family, comprises 13 subspecies, with one being cultivated (D. carota L. ssp. sativus (Hoffm.) Arcang.) and the remaining being wild. Traditionally, the wild carrot has been recognized for its antilithic, diuretic, carminative, antiseptic, and anti-inflammatory properties and has been employed in the treatment of urinary calculus, cystitis, gout, prostatitis, and cancer. While extensive literature is available on the phytochemical, pharmacological, and therapeutic evaluations of the cultivated carrot, limited information has been published on the wild carrot. A thorough search was conducted on the phytochemical composition, folk-medicine uses, and pharmacological properties of wild carrot subspecies (Daucus carota L. ssp. carota). Various electronic databases were consulted, and the literature spanning from 1927 to early 2023 was reviewed. Thirteen wild Daucus carota subspecies were analyzed, revealing over 310 compounds, including terpenoids, phenylpropenoids, flavonoids, and phenolic acids, with 40 constituting more than 3% of the composition. This review also highlights the antioxidant, anticancer, antipyretic, analgesic, antibacterial, antifungal, hypolipidemic, and hepato- and gastroprotective properties of wild carrot subspecies. Existing in vitro and in vivo studies support their traditional uses in treating infections, inflammation, and cancer. However, further research on other subspecies is required to confirm additional applications. Well-designed preclinical and clinical trials are still necessary to establish the safety and efficacy of wild Daucus carota for human use.

Apolipoprotein E-depletion accelerates arterial fat deposition in the spontaneously hypertensive rat

Hypertension and atherosclerosis are often found in one patient causing serious cardiovascular events. An animal model simultaneously expressing hypertension and atherosclerosis would be useful to study such a complex risk status. We therefore attempted to introduce a null mutation of the apolipoprotein E (ApoE) gene into the spontaneously hypertensive rat (SHR) using CRISPR/Cas9 to establish a genetic model for atherosclerosis with hypertension. We successfully established SHRApoE(-/-) having a 13-bps deletion in the 5'-end of ApoE gene. Deletion of ApoE protein was confirmed by Western blotting. Blood pressure of SHRApoE(-/-) was comparable to that of SHR. Feeding the rats with high fat high cholesterol diet (HFD) caused a significant increase in LDL cholesterol as well as in triglyceride in SHRApoE(-/-). After 8 weeks of HFD loading, superficial fat deposition was observed both in the aorta and the mesenteric arteries of SHRApoE(-/-) instead of mature atheromatous lesions found in humans. In addition, a null mutation of peroxiredoxin 2 (Prdx2) was introduced into SHRApoE(-/-) to examine the effect of increased oxidative stress on the development of atherosclerosis. SHR with the double depletion of ApoE and Prdx2 did not show mature atheroma either. Further, salt loading did not promote development of atheroma although it accelerated the development of fat deposition. These results indicated that when compared with ApoE-knockout mice, SHRApoE(-/-) was more resistant to atherosclerosis even though they have severe hypertension.

From reactive species to disease development: Effect of oxidants and antioxidants on the cellular biomarkers

The influence of modern lifestyle, diet, exposure to chemicals such as phytosanitary substances, together with sedentary lifestyles and lack of exercise play an important role in inducing reactive stress (RS) and disease. The imbalance in the production and scavenging of free radicals and the induction of RS (oxidative, nitrosative, and halogenative) plays an essential role in the etiology of various chronic pathologies, such as cardiovascular diseases, diabetes, neurodegenerative diseases, and cancer. The implication of free radicals and reactive species injury in metabolic disturbances and the onset of many diseases have been accumulating for several decades, and are now accepted as a major cause of many chronic diseases. Exposure to elevated levels of free radicals can cause molecular structural impact on proteins, lipids, and DNA, as well as functional alteration of enzyme homeostasis, leading to aberrations in gene expression. Endogenous depletion of antioxidant enzymes can be mitigated using exogenous antioxidants. The current interest in the use of exogenous antioxidants as adjunctive agents for the treatment of human diseases allows a better understanding of these diseases, facilitating the development of new therapeutic agents with antioxidant activity to improve the treatment of various diseases. Here we examine the role that RS play in the initiation of disease and in the reactivity of free radicals and RS in organic and inorganic cellular components.

Curative Effect of AD-MSCs against Cisplatin-Induced Hepatotoxicity in Rats is Potentiated by Azilsartan: Targeting Oxidative Stress, MAPK, and Apoptosis Signaling Pathways

Despite its clinical value, cisplatin (CISP) is complicated by marked hepatotoxicity via inducing oxidative stress, inflammatory, and apoptotic pathways. This study aims to explore the protective impact of azilsartan (AZIL), an antihypertensive drug, in addition to adipose tissue-derived mesenchymal stem cells (AD-MSCs) on CISP-induced hepatotoxicity. After characterization and labeling of AD-MSCs by PKH26 dye, 54 Wistar male albino rats were randomly divided into nine groups: I (CONT), II (AZIL.H), III (CISP), IV (CISP + AZIL.L), V (CISP + AZIL.H), VI (CISP + AD-MSCs), VII (CISP + AZIL.L + AD-MSCs), VIII (CISP + AZIL.H + AD-MSCs), and IX (CISP + VITA C). Serum alanine aminotransferase (ALT), alanine aminotransferase (AST), and albumin levels were determined. Assessment of reactive oxygen species, malondialdehyde, and glutathione contents, and superoxide dismutase activity and histopathological evaluations were done on hepatic tissue. Quantitative real-time PCR was utilized to estimate the expression of TNF-α and IL-6 genes. Cell homing of labeled AD-MSCs to the liver tissues was investigated. Hepatic expression of JNK1/2, ERK1/2, p38, Bax, Bcl-2, and cleaved caspase-3 proteins was investigated by western blot analysis. CISP elevated serum ALT and AST activities, reduced albumin level, and remarkably changed the hepatic architecture. It increased the expression TNF-α and IL-6 genes, raised the expression of JNK1/2, ERK1/2, p38, Bax, and cleaved caspase-3 proteins, and diminished the Bcl-2 protein. By contrast, treatment of animals with either AZIL or AD-MSCs dramatically reduced the effects of CISP injection. Moreover, treatment with combination therapy (AZIL.L or H + AD-MSCs) considerably mitigated all previously mentioned alterations superior to AZIL or AD-MSCs alone, which might be attributed to the AZIL-enhanced homing ability of AD-MSCs into the injured liver tissue. In conclusion, the present findings demonstrated that AZIL improves the hepatoprotective potential of AD-MSCs against CISP-induced hepatotoxicity by modulating oxidative stress, mitogen-activated protein kinase, and apoptotic pathways.

Oxidative stress following spinal cord injury: From molecular mechanisms to therapeutic targets

Spinal cord injury (SCI) is a medical condition that results from severe trauma to the central nervous system; it imposes great psychological and economic burdens on affected patients and their families. The dynamic balance between reactive oxygen species (ROS) and antioxidants is essential for maintaining normal cellular physiological functions. As important intracellular signaling molecules, ROS regulate numerous physiological activities, including vascular reactivity and neuronal function. However, excessive ROS can cause damage to cellular macromolecules, including DNA, lipids, and proteins; this damage eventually leads to cell death. This review discusses the mechanisms of oxidative stress in SCI and describes some signaling pathways that regulate oxidative injury after injury, with the aim of providing guidance for the development of novel SCI treatment strategies.

Melatonin or vitamin C attenuates lead acetate-induced testicular oxidative and inflammatory damage in mice by inhibiting oxidative stress mediated NF-κB signaling

Lead (Pb) acts as an environmental endocrine disruptor and has negative effects in animals; excessive accumulation of lead causes reproductive dysfunction in male animals. Oxidative stress plays a vital role in Pb-induced injury. However, the mechanisms underlying chronic testicular toxicity of Pb remain unclear. In this study, we aimed to determine the effects of lead acetate on reproductive function in male mice, identify the underlying mechanisms, and test counter measures to alleviate the toxic effects. Male mice were dosed with lead acetate (500 mg/L) in free drinking water for 12 weeks, and administered melatonin (5 mg/kg) or vitamin C (500 mg/kg) by intraperitoneal injection. Blood from the eyeball, testicles, and sperm from the caudal epididymis were collected after 12 weeks and analyzed. Pb exposure reduced sperm count and motility, increased sperm malformation (P < 0.01), disrupted testicular morphology and structure, and decreased the expression of steroid hormone synthesis-related enzymes and serum testosterone concentration (P < 0.01). Pb also increased the number of inflammatory cells and the levels of the pro-inflammatory cytokines TNF-α and IL-6 (P < 0.01), and activated NF-κB signaling. Furthermore, the ROS yield and oxidation indicators LPO and MDA were significantly increased (P < 0.01), and the antioxidant indicators T-AOC, SOD, and GSH were significantly reduced (P < 0.01). Treatment with melatonin or vitamin C reversed the effects of lead acetate; vitamin C was more effective in restoring SOD activity (P < 0.01) and enhancing ZO-1 protein levels (P < 0.01). Thus, long-term exposure to lead acetate at low concentrations could adversely affect sperm quality and induce inflammatory damage by oxidative stress mediated NF-κB signaling. Vitamin C could act as a protective agent and improve reproductive dysfunction in male animals after lead accumulation.

Oxidation is an underappreciated post-translational modification in the regulation of immune responses associated with changes in phosphorylation

Although macrophages are known to be affected by their redox status, oxidation is not yet a well-recognized post-translational modification (PTM) in regulating macrophages and immune cells in general. While it has been described that the redox status of single cysteines in specific proteins is relevant for macrophage functions, global oxidation information is scarce. Hence, we globally assessed the impact of oxidation on macrophage activation using untargeted proteomics and PTM-omics. We exposed THP-1 macrophages to lipopolysaccharide (LPS) for 4 h and 24 h and applied a sequential iodoTMT labeling approach to get information on overall oxidation as well as reversible oxidation of cysteines. Thus, we identified 10452 oxidation sites, which were integratively analyzed with 5057 proteins and 7148 phosphorylation sites to investigate their co-occurance with other omics layers. Based on this integrative analysis, we found significant upregulation of several immune-related pathways, e.g. toll-like receptor 4 (TLR4) signaling, for which 19 proteins, 7 phosphorylation sites, and 39 oxidation sites were significantly affected, highlighting the relevance of oxidations in TLR4-induced macrophage activation. Co-regulation of oxidation and phosphorylation was observed, as evidenced by multiply modified proteins related to inflammatory pathways. Additionally, we observed time-dependent effects, with differences in the dynamics of oxidation sites compared to proteins and phosphorylation sites. Overall, this study highlights the importance of oxidation in regulating inflammatory processes and provides a method that can be readily applied to study the cellular redoxome globally.

Glutaredoxin attenuates glutathione levels via deglutathionylation of Otub1 and subsequent destabilization of system xC. SCIENCE ADVANCES 2023;9:eadi5192. [PMID: 37703360 PMCID: PMC10499329 DOI: 10.1126/sciadv.adi5192]

Glutathione (GSH) is a critical component of the cellular redox system that combats oxidative stress. The glutamate-cystine antiporter, system xC-, is a key player in GSH synthesis that allows for the uptake of cystine, the rate-limiting building block of GSH. It is unclear whether GSH or GSH-dependent protein oxidation [protein S-glutathionylation (PSSG)] regulates the activity of system xC-. We demonstrate that an environment of enhanced PSSG promotes GSH increases via a system xC--dependent mechanism. Absence of the deglutathionylase, glutaredoxin (GLRX), augmented SLC7A11 protein and led to significant increases of GSH content. S-glutathionylation of C23 or C204 of the deubiquitinase OTUB1 promoted interaction with the E2-conjugating enzyme UBCH5A, leading to diminished ubiquitination and proteasomal degradation of SLC7A11 and augmentation of GSH, effects that were reversed by GLRX. These findings demonstrate an intricate link between GLRX and GSH via S-glutathionylation of OTUB1 and system xC- and illuminate a previously unknown feed-forward regulatory mechanism whereby enhanced GSH protein oxidation augments cellular GSH.

Protein kinase C: A potential therapeutic target for endothelial dysfunction in diabetes

Protein kinase C (PKC) is a family of serine/threonine protein kinases that play an important role in many organs and systems and whose activation contributes significantly to endothelial dysfunction in diabetes. The increase in diacylglycerol (DAG) under high glucose conditions mediates PKC activation and synthesis, which stimulates oxidative stress and inflammation, resulting in impaired endothelial cell function. This article reviews the contribution of PKC to the development of diabetes-related endothelial dysfunction and summarizes the drugs that inhibit PKC activation, with the aim of exploring therapeutic modalities that may alleviate endothelial dysfunction in diabetic patients.

Chrono-modulated effects of external stressors on oxidative stress and damage in humans: A scoping review on night shift work

BACKGROUND

Oxidative stress and tissue damage (OSD) play a pivotal role as an early-stage process in chronic disease pathogenesis. However, there has been little research to better understand the temporal (χρόνος[chronos]) dimensions of OSD process associated with environmental (non-genetic, including behaviors/lifestyle) and/or occupational stressors, like night shift work. OSD processes have recently attracted attention in relation to time-resolved external stressor trajectories in personalized medicine (prevention) initiatives, as they seem to interact with circadian clock systems towards the improved delineation of the early stages of (chronic) disease process.

OBJECTIVES

This work critically reviewed human studies targeting the temporal dynamics of OSD and circadian clock system's activity in response to environmental/occupational stressors; the case of night shift work was examined.

METHODS

Being a key stressor influencing OSD processes and circadian rhythm, night shift work was evaluated as part of a scoping review of research in OSD, including inflammatory and metabolic processes to determine the extent of OSD research undertaken in human populations, methodologies, tools and biomarkers used and the extent that the temporal dimensions of exposure and biological effect(s) were accounted for. Online databases were searched for papers published from 2000 onwards, resulting in the selection of 53 original publications.

RESULTS AND DISCUSSION

The majority of studies (n = 41) took place in occupational settings, while the rest were conducted in the general population or patient groups. Most occupational studies targeted outcomes of oxidative stress/damage (n = 19), followed by the combination of OSD with inflammatory response (n = 10), and studies focused on metabolic outcomes (n = 12). Only a minor fraction of the studies measured biomarkers related to circadian rhythm, such as, melatonin, its metabolite, or cortisol. Night shift work was associated with select biomarkers of OSD and inflammation, albeit with mixed results. Although much progress in delineating the biological mechanisms of OSD process has been made, an equally thorough investigation on the temporal trajectory of OSD processes as triggered by environmental/occupational stressors in human studies has yet to fully evolve.

Gut microbes involvement in gastrointestinal cancers through redox regulation

Gastrointestinal (GI) cancers are among the most common and lethal cancers worldwide. GI microbes play an important role in the occurrence and development of GI cancers. The common mechanisms by which GI microbes may lead to the occurrence and development of cancer include the instability of the microbial internal environment, secretion of cancer-related metabolites, and destabilization of the GI mucosal barrier. In recent years, many studies have found that the relationship between GI microbes and the development of cancer is closely associated with the GI redox level. Redox instability associated with GI microbes may induce oxidative stress, DNA damage, cumulative gene mutation, protein dysfunction and abnormal lipid metabolism in GI cells. Redox-related metabolites of GI microbes, such as short-chain fatty acids, hydrogen sulfide and nitric oxide, which are involved in cancer, may also influence GI redox levels. This paper reviews the redox reactions of GI cells regulated by microorganisms and their metabolites, as well as redox reactions in the cancer-related GI microbes themselves. This study provides a new perspective for the prevention and treatment of GI cancers.

Human resident liver myeloid cells protect against metabolic stress in obesity

Although multiple populations of macrophages have been described in the human liver, their function and turnover in patients with obesity at high risk of developing non-alcoholic fatty liver disease (NAFLD) and cirrhosis are currently unknown. Herein, we identify a specific human population of resident liver myeloid cells that protects against the metabolic impairment associated with obesity. By studying the turnover of liver myeloid cells in individuals undergoing liver transplantation, we find that liver myeloid cell turnover differs between humans and mice. Using single-cell techniques and flow cytometry, we determine that the proportion of the protective resident liver myeloid cells, denoted liver myeloid cells 2 (LM2), decreases during obesity. Functional validation approaches using human 2D and 3D cultures reveal that the presence of LM2 ameliorates the oxidative stress associated with obese conditions. Our study indicates that resident myeloid cells could be a therapeutic target to decrease the oxidative stress associated with NAFLD.

Targeting Oxidative Stress with Polyphenols to Fight Liver Diseases

Reactive oxygen species (ROS) are important second messengers in many metabolic processes and signaling pathways. Disruption of the balance between ROS generation and antioxidant defenses results in the overproduction of ROS and subsequent oxidative damage to biomolecules and cellular components that disturb cellular function. Oxidative stress contributes to the initiation and progression of many liver pathologies such as ischemia-reperfusion injury (LIRI), non-alcoholic fatty liver disease (NAFLD), and hepatocellular carcinoma (HCC). Therefore, controlling ROS production is an attractive therapeutic strategy in relation to their treatment. In recent years, increasing evidence has supported the therapeutic effects of polyphenols on liver injury via the regulation of ROS levels. In the current review, we summarize the effects of polyphenols, such as quercetin, resveratrol, and curcumin, on oxidative damage during conditions that induce liver injury, such as LIRI, NAFLD, and HCC.

Advanced Delivery System of Polyphenols for Effective Cancer Prevention and Therapy

Polyphenols from plants such as fruits and vegetables are phytochemicals with physiological and pharmacological activity as potential drugs to modulate oxidative stress and inflammation associated with cardiovascular disease, chronic disease, and cancer. However, due to the limited water solubility and bioavailability of many natural compounds, their pharmacological applications have been limited. Researchers have made progress in the development of nano- and micro-carriers that can address these issues and facilitate effective drug delivery. The currently developed drug delivery systems maximize the fundamental effects in various aspects such as absorption rate, stability, cellular absorption, and bioactivity of polyphenols. This review focuses on the antioxidant and anti-inflammatory effects of polyphenols enhanced by the introduction of drug delivery systems, and ultimately discusses the inhibition of cancer cell proliferation, growth, and angiogenesis.

Role of lipocalin 2 in stroke

Stroke is the second leading cause of death worldwide; however, the treatment choices available to neurologists are limited in clinical practice. Lipocalin 2 (LCN2) is a secreted protein, belonging to the lipocalin superfamily, with multiple biological functions in mediating innate immune response, inflammatory response, iron-homeostasis, cell migration and differentiation, energy metabolism, and other processes in the body. LCN2 is expressed at low levels in the brain under normal physiological conditions, but its expression is significantly up-regulated in multiple acute stimulations and chronic pathologies. An up-regulation of LCN2 has been found in the blood/cerebrospinal fluid of patients with ischemic/hemorrhagic stroke, and could serve as a potential biomarker for the prediction of the severity of acute stroke. LCN2 activates reactive astrocytes and microglia, promotes neutrophil infiltration, amplifies post-stroke inflammation, promotes blood-brain barrier disruption, white matter injury, and neuronal death. Moreover, LCN2 is involved in brain injury induced by thrombin and erythrocyte lysates, as well as microvascular thrombosis after hemorrhage. In this paper, we review the role of LCN2 in the pathological processes of ischemic stroke; intracerebral hemorrhage; subarachnoid hemorrhage; and stroke-related brain diseases, such as vascular dementia and post-stroke depression, and their underlying mechanisms. We hope that this review will help elucidate the value of LCN2 as a therapeutic target in stroke.

Oxidative stress and neuroimmune proteins in a mouse model of autism

Oxidative stress including decreased antioxidant enzyme activities, elevated lipid peroxidation, and accumulation of advanced glycation end products in the blood from children with autism spectrum disorders (ASD) has been reported. The mechanisms affecting the development of ASD remain unclear; however, toxic environmental exposures leading to oxidative stress have been proposed to play a significant role. The BTBRT+Itpr3tf/J (BTBR) strain provides a model to investigate the markers of oxidation in a mouse strain exhibiting ASD-like behavioral phenotypes. In the present study, we investigated the level of oxidative stress and its effects on immune cell populations, specifically oxidative stress affecting surface thiols (R-SH), intracellular glutathione (iGSH), and expression of brain biomarkers that may contribute to the development of the ASD-like phenotypes that have been observed and reported in BTBR mice. Lower levels of cell surface R-SH were detected on multiple immune cell subpopulations from blood, spleens, and lymph nodes and for sera R-SH levels of BTBR mice compared to C57BL/6 J (B6) mice. The iGSH levels of immune cell populations were also lower in the BTBR mice. Elevated protein expression of GATA3, TGM2, AhR, EPHX2, TSLP, PTEN, IRE1α, GDF15, and metallothionein in BTBR mice is supportive of an increased level of oxidative stress in BTBR mice and may underpin the pro-inflammatory immune state that has been reported in the BTBR strain. Results of a decreased antioxidant system suggest an important oxidative stress role in the development of the BTBR ASD-like phenotype.

Peroxiredoxins and Hypoxia-Inducible Factor-1α in Duodenal Tissue: Emerging Factors in the Pathophysiology of Pediatric Celiac Disease Patients

Celiac disease (CD) is an autoimmune enteropathy. Peroxiredoxins (PRDXs) are powerful antioxidant enzymes having an important role in significant cellular pathways including cell survival, apoptosis, and inflammation. This study aimed at investigating the expression levels of all PRDX isoforms (1-6) and their possible relationships with a transcription factor, HIF-1α, in the small intestinal tissue samples of pediatric CD patients. The study groups consisted of first-diagnosed CD patients (n = 7) and non-CD patients with functional gastrointestinal tract disorders as the controls (n = 7). The PRDXs and HIF-1α expression levels were determined by using real-time PCR and Western blotting in duodenal biopsy samples. It was observed that the mRNA and protein expression levels of PRDX 5 were significantly higher in the CD patients, whereas the PRDX 1, -2, and -4 expressions were decreased in each case compared to the control group. No significant differences were detected in the PRDX 3 and PRDX 6 expressions. The expression of HIF-1α was also significantly elevated in CD patients. These findings indicate, for the first time, that PRDXs, particularly PRDX 5, may play a significant role in the pathogenesis of CD. Furthermore, our results suggest that HIF-1α may upregulate PRDX-5 transcription in the duodenal tissue of CD.

Disequilibrium in the Thioredoxin Reductase-1/Thioredoxin-1 Redox Couple Is Associated with Increased T-Cell Apoptosis in Children with Autism

Autism spectrum disorder (ASD) is a neuropsychiatric childhood disorder that affects social skill and language development, and is characterized by persistent stereotypic behaviors, restricted social interests, and impaired language/social skills. ASD subjects have dysregulated immune responses due to impairment in inflammatory and antioxidant signaling in immune cells, such as T cells. Thioredoxin reductase-1 (TrxR1) and thioredoxin-1 (Trx1) play a crucial role in the maintenance of redox equilibrium in several immune cells, including T cells. T-cell apoptosis plays a crucial role in the pathogenesis of several inflammatory diseases. However, it remains to be explored how the TrxR1/Trx1 redox couple affects T-cells apoptosis in ASD and typically developing control (TDC) groups. Therefore, this single-center cross-sectional study explored the expression/activity of TrxR1/Trx1, and Bcl2, 7-AAD/annexin V immunostaining in T cells of ASD (n = 25) and TDC (n = 22) groups. Further, effects of the LPS were determined on apoptosis in TDC and ASD T cells. Our data show that T cells have increased TrxR1 expression, while having decreased Trx1 expression in the ASD group. Further, TrxR enzymatic activity was also elevated in T cells of the ASD group. Furthermore, T cells of the ASD group had a decreased Bcl2 expression and an increased % of annexin V immunostaining. Treatment of T cells with LPS caused greater apoptosis in the ASD group than the TDC group, with same treatment. These data reveal that the redox couple TrxR1/Trx1 is dysregulated in T cells of ASD subjects, which is associated with decreased Bcl2 expression and increased apoptosis. This may lead to decreased survival of T cells in ASD subjects during chronic inflammation. Future studies should investigate environmental factors, such as gut dysbiosis and pollutants, that may cause abnormal immune responses in the T cells of ASD subjects due to chronic inflammation.

Coordinated reprogramming of renal cancer transcriptome, metabolome and secretome associates with immune tumor infiltration

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) is the most common subtype of renal cancer. The molecules (proteins, metabolites) secreted by tumors affect their extracellular milieu to support cancer progression. If secreted in amounts detectable in plasma, these molecules can also serve as useful, minimal invasive biomarkers. The knowledge of ccRCC tumor microenvironment is fragmentary. In particular, the links between ccRCC transcriptome and the composition of extracellular milieu are weakly understood. In this study, we hypothesized that ccRCC transcriptome is reprogrammed to support alterations in tumor microenvironment. Therefore, we comprehensively analyzed ccRCC extracellular proteomes and metabolomes as well as transcriptomes of ccRCC cells to find molecules contributing to renal tumor microenvironment.

METHODS

Proteomic and metabolomics analysis of conditioned media isolated from normal kidney cells as well as five ccRCC cell lines was performed using mass spectrometry, with the following ELISA validation. Transcriptomic analysis was done using microarray analysis and validated using real-time PCR. Independent transcriptomic and proteomic datasets of ccRCC tumors were used for the analysis of gene and protein expression as well as the level of the immune infiltration.

RESULTS

Renal cancer secretome contained 85 proteins detectable in human plasma, consistently altered in all five tested ccRCC cell lines. The top upregulated extracellular proteins included SPARC, STC2, SERPINE1, TGFBI, while downregulated included transferrin and DPP7. The most affected extracellular metabolites were increased 4-hydroxy-proline, succinic acid, cysteine, lactic acid and downregulated glutamine. These changes were associated with altered expression of genes encoding the secreted proteins (SPARC, SERPINE1, STC2, DPP7), membrane transporters (SLC16A4, SLC6A20, ABCA12), and genes involved in protein trafficking and secretion (KIF20A, ANXA3, MIA2, PCSK5, SLC9A3R1, SYTL3, and WNTA7). Analogous expression changes were found in ccRCC tumors. The expression of SPARC predicted the infiltration of ccRCC tumors with endothelial cells. Analysis of the expression of the 85 secretome genes in > 12,000 tumors revealed that SPARC is a PanCancer indicator of cancer-associated fibroblasts' infiltration.

CONCLUSIONS

Transcriptomic reprogramming of ccRCC supports the changes in an extracellular milieu which are associated with immune infiltration. The proteins identified in our study represent valuable cancer biomarkers detectable in plasma.

An overview of natural products that modulate the expression of non-coding RNAs involved in oxidative stress and inflammation-associated disorders

Oxidative stress is a state in which oxidants are produced in excess in the body's tissues and cells, resulting in a biological imbalance amid the generation of reactive oxygen and nitrogen species (RONS) from redox reactions. In case of insufficient antioxidants to balance, the immune system triggers signaling cascades to mount inflammatory responses. Oxidative stress can have deleterious effects on major macromolecules such as lipids, proteins, and nucleic acids, hence, Oxidative stress and inflammation are among the multiple factors contributing to the etiology of several disorders such as diabetes, cancers, and cardiovascular diseases. Non-coding RNAs (ncRNAs) which were once referred to as dark matter have been found to function as key regulators of gene expression through different mechanisms. They have dynamic roles in the onset and development of inflammatory and oxidative stress-related diseases, therefore, are potential targets for the control of those diseases. One way of controlling those diseases is through the use of natural products, a rich source of antioxidants that have drawn attention with several studies showing their involvement in combating chronic diseases given their enormous gains, low side effects, and toxicity. In this review, we highlighted the natural products that have been reported to target ncRNAs as mediators of their biological effects on oxidative stress and several inflammation-associated disorders. Those natural products include Baicalein, Tanshinone IIA, Geniposide, Carvacrol/Thymol, Triptolide, Oleacein, Curcumin, Resveratrol, Solarmargine, Allicin, aqueous extract or pulp of Açai, Quercetin, and Genistein. We also draw attention to some other compounds including Zanthoxylum bungeanum, Canna genus rhizome, Fuzi-ganjiang herb pair, Aronia melanocarpa, Peppermint, and Gingerol that are effective against oxidative stress and inflammation-related disorders, however, have no known effect on ncRNAs. Lastly, we touched on the many ncRNAs that were found to play a role in oxidative stress and inflammation-related disorders but have not yet been investigated as targets of a natural product. Shedding more light into these two last points of shadow will be of great interest in the valorization of natural compounds in the control and therapy of oxidative stress- and inflammation-associated disorders.

Brain edema formation and therapy after intracerebral hemorrhage

Intracerebral hemorrhage (ICH) accounts for about 10% of all strokes in the United States of America causing a high degree of disability and mortality. There is initial (primary) brain injury due to the mechanical disruption caused by the hematoma. There is then secondary injury, triggered by the initial injury but also the release of various clot-derived factors (e.g., thrombin and hemoglobin). ICH alters brain fluid homeostasis. Apart from the initial hematoma mass, ICH causes blood-brain barrier disruption and parenchymal cell swelling, which result in brain edema and intracranial hypertension affecting patient prognosis. Reducing brain edema is a critical part of post-ICH care. However, there are limited effective treatment methods for reducing perihematomal cerebral edema and intracranial pressure in ICH. This review discusses the mechanisms underlying perihematomal brain edema formation, the effects of sex and age, as well as how edema is resolved. It examines progress in pharmacotherapy, particularly focusing on drugs which have been or are currently being investigated in clinical trials.

Role of Gut Microbiota and Oxidative Stress in the Progression of Transplant-Related Complications following Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation (HSCT), also known as bone marrow transplantation, has curative potential for various hematologic malignancies but is associated with risks such as graft-versus-host disease (GvHD), severe bloodstream infection, viral pneumonia, idiopathic pneumonia syndrome (IPS), lung fibrosis, and sinusoidal obstruction syndrome (SOS), which severely deteriorate clinical outcomes and limit the wide application of HSCT. Recent research has provided important insights into the effects of gut microbiota and oxidative stress (OS) on HSCT complications. Therefore, based on recent studies, we describe intestinal dysbiosis and OS in patients with HSCT and review recent molecular findings underlying the causal relationships of gut microbiota, OS, and transplant-related complications, focusing particularly on the involvement of gut microbiota-mediated OS in postengraftment complications. Also, we discuss the use of antioxidative and anti-inflammatory probiotics to manipulate gut microbiota and OS, which have been associated with promising effects in improving HSCT outcomes.

Prx4 acts as DAMP in shrimp, enhancing bacterial resistance via the toll pathway and prophenoloxidase activation

Peroxiredoxin (Prx), an antioxidant enzyme family, has been identified as immune modulating damage-associated molecular patterns (DAMPs) in mammals but not in shrimp. Acute non-lethal heat shock (NLHS) that enhances shrimp Penaeus vannamei resistance to Vibrio parahaemolyticus causing acute hepatopancreatic necrosis disease (VP_AHPND). Among the five P. vannamei Prxs (LvPrx) isoforms, LvPrx4, the most abundant in unchallenged shrimp hemocytes that was upregulated in hemocytes following NLHS treatment, is of great interest. The escalation of the LvPrx4 monomer in hemolymph of NLHS treated shrimp indicates that it probably acts as DAMP. This study revealed that pre-challenge with rLvPrx4 could prolong VP_AHPND-infected shrimp survival, increase prophenoloxidase (proPO) activity and promote Toll pathway-related genes expression mediated by Toll-like receptor (TLR) 1 and 2. The presented findings elucidated the molecular mechanism of LvPrx4 monomer as DAMP in NLHS-induced VP_AHPND resistance by inducing the TLR1/2 signaling pathway and the proPO activating system.

CREB1 and PPAR-α/γ Pathways in Hepatic Ischemia/Reperfusion: Route for Curcumin to Hepatoprotection

Background

Hepatic ischemia/reperfusion injury is a major problem that can exacerbate complications, particularly in liver transplantations.

Objectives

This study aimed to investigate the cellular mechanisms of ischemia/reperfusion injury and hepatoprotection by curcumin.

Methods

Wistar albino rats were divided into four groups as Control, Sham, I/R, and Cur+I/R. Hepatic ischemia/reperfusion was induced in I/R and Cur+I/R animals, the latter of which was also given 50 mg/kg/day of curcumin for 14 days. Liver aminotransferases and the transcription regulators of inflammation (RelA, IκB, PPAR-α, PPAR-γ, CREB1) were examined along with the histological examination.

Results

Hepatic ischemia/reperfusion was found to disrupt hepatic microstructure and downregulate PPAR-α, PPAR-γ, and CREB1 transcripts. Curcumin supplementation in hepatic ischemia/reperfusion recovered the structural organization and promoted the hepatocyte regeneration while increasing expressions of PPARs and CREB1. RelA and IκB were found unaltered, possibly due to the crosstalk between targeted transcripts by ischemia/reperfusion and curcumin.

Conclusions

In sum, PPAR-α/γ and CREB1 were involved in hepatic ischemia/reperfusion and, moreover, were detected to be stimulated by curcumin. PPAR and CREB pathways were found to provide a route to hepatoprotection for curcumin supplementation as evidenced by the microstructural improvement.

Essential Roles of Peroxiredoxin IV in Inflammation and Cancer

Peroxiredoxin IV (Prx4) is a 2-Cysteine peroxidase with ubiquitous expression in human tissues. Prx4 scavenges hydrogen peroxide and participates in oxidative protein folding in the endoplasmic reticulum. In addition, Prx4 is secreted outside the cell. Prx4 is upregulated in several cancers and is a potential therapeutic target. We have summarized historical and recent advances in the structure, function and biological roles of Prx4, focusing on inflammatory diseases and cancer. Oxidative stress is known to activate pro-inflammatory pathways. Chronic inflammation is a risk factor for cancer development. Hence, redox enzymes such as Prx4 are important players in the crosstalk between inflammation and cancer. Understanding molecular mechanisms of regulation of Prx4 expression and associated signaling pathways in normal physiological and disease conditions should reveal new therapeutic strategies. Thus, although Prx4 is a promising therapeutic target for inflammatory diseases and cancer, further research needs to be conducted to bridge the gap to clinical application.

Prediction of COPD acute exacerbation in response to air pollution using exosomal circRNA profile and Machine learning

Ambient fine particulate matter (PM2.5) is linked to an increased risk of chronic obstructive pulmonary disease (COPD) exacerbations, which significantly increase the risk of mortality in COPD patients. Identifying the subtype of COPD patients who are sensitive to environmental aggressions is necessary. Using in vitro and in vivo PM2.5 exposure models, we demonstrate that exosomal hsa_circ_0005045 is upregulated by PM2.5 and binds to the protein cargo peroxiredoxin2, which functionally aggravates hallmarks of COPD by recruiting neutrophil elastase and triggering in situ release of tumor necrosis factor (TNF)-α by inflammatory cells. The biological function of hsa_circ_0005045 associated with aggravation of COPD is validated using exosome-transplantation and conditional circRNA-knockdown murine models. By sorting the major components of PM2.5, we find that PM2.5-bound heavy metals, which are distinguishable from the components of cigarette smoke, trigger the elevation of exosomal hsa_circ_0005045. Finally, using machine learning models in a cohort with 327 COPD patients, the PM2.5 exposure-sensitive COPD patients are characterized by relatively high hsa_circ_0005045 expression, non-smoking, and group C (mMRC 0-1 (or CAT < 10) and ≥ 2 exacerbations (or ≥ 1 exacerbation leading to hospital admission) in the past year). Thus, our results suggest that environmental reduction in PM2.5 emission provides a targeted approach to protecting non-smoking COPD patients against air pollution-related disease exacerbation.

Systemic inflammation after stroke: implications for post-stroke comorbidities

Immunological mechanisms have come into the focus of current translational stroke research, and the modulation of neuroinflammatory pathways has been identified as a promising therapeutic approach to protect the ischemic brain. However, stroke not only induces a local neuroinflammatory response but also has a profound impact on systemic immunity. In this review, we will summarize the consequences of ischemic stroke on systemic immunity at all stages of the disease, from onset to long‐term outcome, and discuss underlying mechanisms of systemic brain‐immune communication. Furthermore, since stroke commonly occurs in patients with multiple comorbidities, we will also overview the current understanding of the potential role of systemic immunity in common stroke‐related comorbidities, such as cardiac dysfunction, atherosclerosis, diabetes, and infections. Finally, we will highlight how targeting systemic immunity after stroke could improve long‐term outcomes and alleviate comorbidities of stroke patients.

Inflammation resolution in environmental pulmonary health and morbidity

Inflammation and resolution are dynamic processes comprised of inflammatory activation and neutrophil influx, followed by mediator catabolism and efferocytosis. These critical pathways ensure a return to homeostasis and promote repair. Over the past decade research has shown that diverse mediators play a role in the active process of resolution. Specialized pro-resolving mediators (SPMs), biosynthesized from fatty acids, are released during inflammation to facilitate resolution and are deficient in a variety of lung disorders. Failed resolution results in remodeling and cellular deposition through pro-fibrotic myofibroblast expansion that irreversibly narrows the airways and worsens lung function. Recent studies indicate environmental exposures may perturb and deregulate critical resolution pathways. Environmental xenobiotics induce lung inflammation and generate reactive metabolites that promote oxidative stress, injuring the respiratory mucosa and impairing gas-exchange. This warrants recognition of xenobiotic associated molecular patterns (XAMPs) as new signals in the field of inflammation biology, as many environmental chemicals generate free radicals capable of initiating the inflammatory response. Recent studies suggest that unresolved, persistent inflammation impacts both resolution pathways and endogenous regulatory mediators, compromising lung function, which over time can progress to chronic lung disease. Chronic ozone (O3) exposure overwhelms successful resolution, and in susceptible individuals promotes asthma onset. The industrial contaminant cadmium (Cd) bioaccumulates in the lung to impair resolution, and recurrent inflammation can result in chronic obstructive pulmonary disease (COPD). Persistent particulate matter (PM) exposure increases systemic cardiopulmonary inflammation, which reduces lung function and can exacerbate asthma, COPD, and idiopathic pulmonary fibrosis (IPF). While recurrent inflammation underlies environmentally induced pulmonary morbidity and may drive the disease process, our understanding of inflammation resolution in this context is limited. This review aims to explore inflammation resolution biology and its role in chronic environmental lung disease(s).

The effectiveness of vitamin C on quinalphos ileal toxicity: a study of histological, ultrastructural, and oxidative stress markers

There is a significant hazard of human exposure to the organophosphates which is a constant threat, and they are responsible for numerous cases of poisoning and mammalian toxicity annually in non-target wildlife. The antioxidants, including the vitamin C (Vit C), have a protective effect on some organophosphorus compounds-induced organ damage. Quinalphos (QP) is one of these compounds. The investigation's objective is to see if there was any effect of QP on the rat ileum which could be rectified by using Vit C. Three groups of 24 animals were created. As a control, the first group was given pure water. Second group subjected to oral gavages of QPs. Third group rats were given oral gavages of Vit C plus QPs for 10 days. The reaction of ileal enterocytes to food-borne QPs was marked by poorly organized microvilli, numerous vacuoles within them, disrupted nuclei with chromatin margination, disoriented mitochondria, and an expanded intercellular space. The absorptive columnar cell illustrated many vacuoles inside with herniation of microvilli, and normal goblet cells were also seen. Many Paneth cells towards the lumen of intestinal gland contained secretory granules of different sizes and shapes. The histological architecture of the ileal mucosa in the QP plus Vit C group was found to be close to those of healthy controls. The outcomes of this study suggest that administering Vit C in rats treated with QPs protects them from ill dysfunction caused by QP.

Paradigm Shift in Phytochemicals Research: Evolution from Antioxidant Capacity to Anti-Inflammatory Effect and to Roles in Gut Health and Metabolic Syndrome

Food bioactive components, particularly phytochemicals with antioxidant capacity, have been extensively studied over the past two decades. However, as new analytical and molecular biological tools advance, antioxidants related research has undergone significant paradigm shifts. This review is a high-level overview of the evolution of phytochemical antioxidants research. Early research used chemical models to assess the antioxidant capacity of different phytochemicals, which provided important information about the health potential, but the results were overused and misinterpreted despite the lack of biological relevance (Antioxidants v1.0). This led to findings in the anti-inflammatory properties and modulatory effects of cell signaling of phytochemicals (Antioxidants v2.0). Recent advances in the role of diet in modulating gut microbiota have suggested a new phase of food bioactives research along the phytochemicals-gut microbiota-intestinal metabolites-low-grade inflammation-metabolic syndrome axis (Antioxidants v3.0). Polyphenols and carotenoids were discussed in-depth, and future research directions were also provided.

Change in Oxidative Stress and Mitochondrial Dynamics in Response to Elevated Cold-Inducible RNA-Binding Protein in Cardiac Surgery-Associated Acute Kidney Injury

Cardiac surgery-associated acute kidney injury (CSA-AKI) is a common yet serious complication that is closely related to cardiopulmonary bypass (CPB). Extracellular cold-inducible RNA-binding protein (eCIRP) can mediate aseptic inflammation and trigger intracellular oxidative stress. In the present study, expression of serum CIRP was significantly elevated post-CPB ( $785.0\pm 640.5$  pg/mL vs. $149.5\pm 289.1$  pg/mL, $P<0.001$ ) and was positively correlated with CPB duration ( $r=0.502$ , $P<0.001$ ). Patients with high expression of CIRP had higher risks of postoperative AKI than patients with low CIRP expression (OR: 1.67, 95% CI 1.04-2.68). In a rat CPB model, the serum CIRP concentration increased significantly after CPB. Similarly, the levels of Scr and BUN significantly increased 4 hours after CPB. KIM-1 and NGAL mRNA levels in the CPB group were 8.2 and 4.3 times higher than the sham group, respectively. In addition, the levels of inflammatory cell infiltration, oxidative stress, and apoptosis in the renal tissue of the CPB group were significantly higher compared to the sham group. The expression levels of serum inflammatory factors at 4 hours post-CPB were also increased. Administration of recombinant human CIRP protein promoted the expression of NADPH oxidase via the TLR-4/MyD88 pathway, aggravated intracellular oxidative stress, mediated mitochondrial dynamics disorder, and eventually increased apoptosis in HK-2 cells. However, the CIRP inhibitor C23 improved the CIRP-mediated oxidative stress and mitochondrial dysfunction in both rat and cell models. In summary, elevated CIRP could mediate oxidative stress and mitochondrial dynamics in the kidney to promote CSA-AKI.

Systemic oxidative stress associates with new-onset hypertension in the general population

BACKGROUND

Oxidative stress is known to be involved in the development of hypertension, but accurate redox biomarkers predicting the risk of developing hypertension are scarce. Serum free sulfhydryl groups (R-SH, free thiols) have been shown to accurately reflect systemic oxidative stress in various conditions. In this study, we aimed to investigate associations between serum free thiols and the risk of developing new-onset hypertension in a population-based cohort study.

METHODS

Subjects (n = 3,575) who participated in the Prevention of REnal and Vascular ENd-stage Disease (PREVEND) study, a prospective, population-based cohort study in the Netherlands, were included. Baseline protein-adjusted serum free thiols were studied for their associations with the development of hypertension, defined as a systolic blood pressure (SBP) of at least 140 mmHg, a diastolic blood pressure (DBP) of at least 90 mmHg, or the first usage of antihypertensive medication. Subjects with hypertension at baseline were excluded from the study.

RESULTS

Mean protein-adjusted serum free thiols at baseline was 5.16 μmol/g of protein (range: 1.62-8.41 μmol/g). Protein-adjusted serum free thiols were significantly associated with the risk of incident hypertension (hazard ratio [HR] per doubling 0.60 [95% confidence interval [CI]: 0.49-0.72, P < 0.001), also after adjustment for age and sex (HR 0.81 [95% CI: 0.66-0.91], P < 0.05), but not after additional adjustment for relevant confounding factors (HR 0.90 [95% CI: 0.70-1.15], P = 0.382).

CONCLUSION

Higher levels of serum free thiols, i.e. less oxidative stress, are associated with a decreased risk of developing incident hypertension in subjects from the general population.

Thiol Modifications in the Extracellular Space—Key Proteins in Inflammation and Viral Infection

Posttranslational modifications (PTMs) allow to control molecular and cellular functions in response to specific signals and changes in the microenvironment of cells. They regulate structure, localization, stability, and function of proteins in a spatial and temporal manner. Among them, specific thiol modifications of cysteine (Cys) residues facilitate rapid signal transduction. In fact, Cys is unique because it contains the highly reactive thiol group that can undergo different reversible and irreversible modifications. Upon inflammation and changes in the cellular microenvironment, many extracellular soluble and membrane proteins undergo thiol modifications, particularly dithiol–disulfide exchange, S-glutathionylation, and S-nitrosylation. Among others, these thiol switches are essential for inflammatory signaling, regulation of gene expression, cytokine release, immunoglobulin function and isoform variation, and antigen presentation. Interestingly, also the redox state of bacterial and viral proteins depends on host cell-mediated redox reactions that are critical for invasion and infection. Here, we highlight mechanistic thiol switches in inflammatory pathways and infections including cholera, diphtheria, hepatitis, human immunodeficiency virus (HIV), influenza, and coronavirus disease 2019 (COVID-19).

Multi-Target Effects of ß-Caryophyllene and Carnosic Acid at the Crossroads of Mitochondrial Dysfunction and Neurodegeneration: From Oxidative Stress to Microglia-Mediated Neuroinflammation

Inflammation and oxidative stress are interlinked and interdependent processes involved in many chronic diseases, including neurodegeneration, diabetes, cardiovascular diseases, and cancer. Therefore, targeting inflammatory pathways may represent a potential therapeutic strategy. Emerging evidence indicates that many phytochemicals extracted from edible plants have the potential to ameliorate the disease phenotypes. In this scenario, ß-caryophyllene (BCP), a bicyclic sesquiterpene, and carnosic acid (CA), an ortho-diphenolic diterpene, were demonstrated to exhibit anti-inflammatory, and antioxidant activities, as well as neuroprotective and mitoprotective effects in different in vitro and in vivo models. BCP essentially promotes its effects by acting as a selective agonist and allosteric modulator of cannabinoid type-2 receptor (CB2R). CA is a pro-electrophilic compound that, in response to oxidation, is converted to its electrophilic form. This can interact and activate the Keap1/Nrf2/ARE transcription pathway, triggering the synthesis of endogenous antioxidant “phase 2” enzymes. However, given the nature of its chemical structure, CA also exhibits direct antioxidant effects. BCP and CA can readily cross the BBB and accumulate in brain regions, giving rise to neuroprotective effects by preventing mitochondrial dysfunction and inhibiting activated microglia, substantially through the activation of pro-survival signalling pathways, including regulation of apoptosis and autophagy, and molecular mechanisms related to mitochondrial quality control. Findings from different in vitro/in vivo experimental models of Parkinson’s disease and Alzheimer’s disease reported the beneficial effects of both compounds, suggesting that their use in treatments may be a promising strategy in the management of neurodegenerative diseases aimed at maintaining mitochondrial homeostasis and ameliorating glia-mediated neuroinflammation.

Shotgun Proteomics for the Identification and Profiling of the Tear Proteome of Keratoconus Patients

Purpose

The qualitative approach followed in this study aims to obtain an extensive view of the keratoconus (KC) tear proteome, which could highlight proteins previously undetected and enlarge our knowledge of the disease's pathophysiology.

Methods

Twenty-five patients diagnosed with KC and 25 control subjects were studied in a prospective, cross-sectional study. KC screening examinations, including clinical and tomographic examinations, were performed on all participants. Tear samples were collected using Schirmer strips and analyzed by liquid chromatography-tandem mass spectrometry in a data-dependent workflow. A spectral count was used as a semiquantification tool. The tear proteomes of both groups were identified and profiled, and the functional interactions and biological characterization of differential proteins were analyzed using in silico tools.

Results

We identified a total of 232 proteins, of whom 133 were expressed in both groups’ samples; 41 were observed only in control samples and 58 were identified just in tears of patients with KC. A semiquantitative analysis showed the dysregulation of 17 proteins in the KC samples. An in silico analysis linked proteins only expressed in KC samples to oxidative stress, skin development, and apoptosis. The dysregulation of proteins involved in iron transport, inflammation, oxidative stress, and protease inhibition was observed in the semiquantitative results.

Conclusions

A shotgun analysis showed that the tear proteome of patients with KC differed from controls by more than one-third of the total proteins identified, highlighting the relationship of the proteins only expressed in KC tears with processes of cell death, oxidative damage, and inflammation. The underexpression of proteins involved in iron pathways might support the iron imbalance as a contributing factor to cellular damage and death in KC disease.

Can Scoliotic Discs Be Controls for Molecular Studies in Intervertebral Disc Research? Insights From Proteomics

STUDY DESIGN

Proteomic analysis of human intervertebral discs.

OBJECTIVES

To compare the characters of scoliotic discs and discs from magnetic resonance imaging (MRI)-normal voluntary organ donors controls used in disc research employing proteomics and establish "true controls" that can be utilized for future intervertebral disc (IVD) research.

METHODS

Eight MRI-normal discs from 8 brain-dead voluntary organ donors (ND) and 8 scoliotic discs (SD) from 3 patients who underwent anterior surgery for adolescent idiopathic scoliosis were subjected to tandem mass spectrometry, and further analysis was performed.

RESULTS

Mass spectrometry identified a total of 235 proteins in ND and 438 proteins in the SD group. Proteins involved in extracellular matrix integrity (Versican, keratins KRT6A, KRT14, KRT5, and KRT 13A1, A-kinase anchor protein 13, coagulation factor XIII A chain, proteoglycan 4) and proteins involved in transcription and DNA repair (Von Willebrand factor A domain-containing 3B, eukaryotic initiation factor 2B, histone H4, leukocyte cell-derived chemotaxin 2) were found to be downregulated in SD. Inflammatory proteins (C3, C1S), and oxidative stress response proteins (peroxiredoxin-2,6, catalase, myeloperoxidase, apolipoprotein E) were found to be upregulated in SD. These changes were reflected at the pathway level also.

CONCLUSION

Findings of our study confirm that scoliotic discs have an abundance of inflammatory, oxidative stress response proteins, which are either absent or downregulated in the ND group indicating that scoliotic discs are not pathologically inert. Furthermore, this study has established MRI-normal discs from voluntary organ donors as the "true" control for molecular studies in IVD research.

Coenzyme Q10 Supplementation and Its Impact on Exercise and Sport Performance in Humans: A Recovery or a Performance-Enhancing Molecule?

Evidence exists to suggest that ROS induce muscular injury with a subsequent decrease in physical performance. Supplementation with certain antioxidants is important for physically active individuals to hasten recovery from fatigue and to prevent exercise damage. The use of nutritional supplements associated with exercise, with the aim of improving health, optimizing training or improving sports performance, is a scientific concern that not only drives many research projects but also generates great expectations in the field of their application in pathology. Since its discovery in the 1970s, coenzyme Q10 (CoQ10) has been one of the most controversial molecules. The interest in determining its true value as a bioenergetic supplement in muscle contraction, antioxidant or in the inflammatory process as a muscle protector in relation to exercise has been studied at different population levels of age, level of physical fitness or sporting aptitude, using different methodologies of effort and with the contribution of data corresponding to very diverse variables. Overall, in the papers reviewed, although the data are inconclusive, they suggest that CoQ10 supplementation may be an interesting molecule in health or disease in individuals without a pathological deficiency and when used for optimising exercise performance. Considering the results observed in the literature, and as a conclusion of this systematic review, we could say that it is an interesting molecule in sports performance. However, clear approaches should be considered when conducting future research.

Ultrasonic treatment of Dendrobium officinale polysaccharide enhances antioxidant and anti‐inflammatory activity in a mouse D‐galactose‐induced aging model

Utilization of the biological macromolecule Dendrobium officinale polysaccharide (DOP) as a functional ingredient is limited by its high intrinsic viscosity and molecular weight. The goal of the present study was to improve rheological properties of DOP by ultrasonic treatment. Such a treatment resulted in the degradation of DOP and consequent reduction of rheological properties. Among DOP samples treated with ultrasonication at low (L), medium (M), and high (H) power intensities (25, 50, 75 w/cm²), M‐DOP displayed the highest reactive oxygen species (ROS) and reactive nitrogen species (RNS) radical scavenging activity in vitro. In a mouse D‐galactose (D‐Gal)‐induced aging model, M‐DOP significantly increased activities of antioxidant enzymes and reduced levels of pro‐inflammatory cytokines in liver. Real‐time polymerase chain reaction (RT‐PCR) analysis indicated that M‐DOP upregulated messenger RNA (mRNA) expression of anti‐inflammatory/antioxidant proteins such as Nrf2 (nuclear factor erythroid 2‐related factor), hemeoxygenase‐1 (HO‐1), and NAD(P)H:quinone oxidoreductase (NQO1) in liver. In summary, M‐DOP displayed a strong radical scavenging activity in vitro, and ameliorated liver injury in the mouse aging model through the promotion of Nrf2/HO‐1/NQO1 signaling pathway.