Roles of Oxidative Stress and Nrf2 Signaling in Pathogenic and Non-Pathogenic Cells: A Possible General Mechanism of Resistance to Therapy

A study to determine the effect of nano-selenium and thymoquinone on the Nrf2 gene expression in Alzheimer's disease

INTRODUCTION

Alzheimer's disease is a developing public health concern in aging communities that affects a sizable section of the global population. The risk of Alzheimer's disease increases with age; it affects one-third of males and two-thirds of women. This research attempts to assess the effect of nano-selenium and thymoquinone on Nrf2 gene expression levels in Alzheimer's disease (AD).

METHODS

There were five identical groups of 50 albino male rats: a control group that was healthy; an AD positive control group; an AD group that received nano-selenium (5 mg/kg); an AD group that received thymoquinone (2 mg/kg); and an AD group that received both. The duration of treatment was 4 weeks. The levels of Nrf2 in brain tissues were evaluated using real-time PCR.

RESULTS

Nrf2 mean expression levels in the nano-selenium-treated rats, the thymoquinone-treated rats, and the rats that were given both treatments all increased significantly compared to AD rats with no treatment.

CONCLUSIONS

This study showed that nano-selenium and thymoquinone elevated Nrf2 gene expression levels in AD.

Activation, interaction and intimation of Nrf2 pathway and their mutational studies causing Nrf2 associated cancer

Responses against infection trigger several signaling pathways that lead to the production of cytokines, these cytokines release ROS and RNS, damaging DNA and proteins turn into various diseases including cancer. To combat these harmful cytokines, the Nrf2 pathway is activated. The gene NFE2L2 encodes Nrf2, which is divided into seven conserved domains (Neh1-7). The DLG and ETGE motifs, conserved sequences of amino acid in the Neh2 domain of Nrf2, bind to the BTB domain of Keap1. BTB domain promotes Keap1's homodimerization resulting in Cul3 recruitment providing scaffold formation to E2 ubiquitin ligase to form ubiquitin complex. Under normal conditions, this complex regularly degrades Nrf2. However, once the cell is exposed to oxidative stress by ROS interaction with Keap1 resulting in conformational changes that stabilize the Nrf2. Nrf2 further concentrates on the nucleus where it binds with the transcriptional factor to perform the desired genes transcription for synthesizing SOD, GSH, CAT, and various other proteins which reduce the ROS levels preventing certain diseases. To prevent cells from oxidative stress, molecular hydrogen activates the Nrf2 pathway. To activate the Nrf2 pathway, molecular hydrogen oxidizes the iron porphyrin which acts as an electrophile and interacts with Keap1's cysteine residue.

Effects of natural killer cell‑conditioned medium on UVB‑induced photoaging in human keratinocytes and a human reconstructed skin model

Natural killer (NK) cells produce various cytokines, including interleukin (IL)‑1β, IL‑6, IL‑10, IL‑12, interferon γ, tumor necrosis factor α and transforming growth factor β, which are critical in modulating immune responses. NK cell‑conditioned medium (NK‑CdM), rich in cytokines, has potential applications in therapy and healing. The present study aimed to investigate the protective effect of NK‑CdM against ultraviolet B (UVB)‑mediated photoaging using in vitro and ex vivo models. In human keratinocyte cell line (HaCaT cells), NK‑CdM mitigated UVB‑induced cytotoxicity and suppressed the production of reactive oxygen species. NK‑CdM enhanced the mRNA expression levels of superoxide dismutase 1 (SOD1) and catalase (CAT) and inhibited the reduction in SOD1 and CAT expression levels caused by UVB irradiation. Furthermore, NK‑CdM inhibited the UVB‑mediated nuclear translocation of nuclear factor erythroid 2‑related factor 2. NK‑CdM also prevented UVB‑induced downregulation of filaggrin and involucrin and attenuated the UVB‑induced reduction in hyaluronan synthase (HAS)1, HAS2, HAS3, aquaporin‑3 and hyaluronan levels. Notably, NK‑CdM upregulated the expression of elongation of very long chain fatty acids (ELOVL) enzymes, including ELOVL1, ELOVL5 and ELOVL6, as well as ceramide synthases (CerS), specifically CerS2 and CerS3. Furthermore, NK‑CdM inhibited the UVB‑induced reduction in the levels of these proteins. Overall, these findings suggested that NK‑CdM has the potential to prevent UVB‑mediated photoaging and promote skin health.

Silymarin attenuates post-weaning bisphenol A-induced renal injury by suppressing ferroptosis and amyloidosis through Kim-1/Nrf2/HO-1 signaling modulation in male Wistar rats

Bisphenol A (BPA) is a synthetic chemical used in producing polycarbonate plastics and epoxy resins and is commonly found in everyday items like water bottles and food containers. Although its usefulness cannot be overemphasized, the major challenge is its toxicity, including renal toxicity. BPA has been reported to induce ferroptosis and amyloidosis via the modulation of Nrf2/HO-1 signaling. On the other hand, silymarin activates the Nrf2/HO-1 pathway, thus providing cellular defense. However, the effect of silymarin on BPA-induced renal toxicity is yet to be reported. This study investigated the potential impact of silymarin on renal structure and function following post-weaning BPA exposure. Twenty-four male Wistar rats were randomly assigned into four equal groups. The control was vehicle-treated, while the silymarin-treated received 100 mg/kg/day of silymarin and BPA-treated rats received 50 mg/kg/day of BPA. The BPA + silymarin-treated rats received treatments as BPA-treated and silymarin-treated. Silymarin diminished BPA-induced rise in serum urea, creatinine, BUN, and plasma kim-1 levels. Also, silymarin improved BPA-induced dyslipidemia. More so, silymarin abrogated toxic amyloid formation and improved renal histoarchitecture in BPA-exposed rats. These events were associated with the suppression of BPA-induced rise in renal iron, MDA, TNF-α, IL-1β, and cytochrome c levels, and myeloperoxidase and caspase 3 activities by silymarin therapy. Furthermore, silymarin attenuated BPA-induced downregulation of Nrf2 and GSH levels, and HO-1, GPX4, SOD, catalase, GST, and GR activities. In conclusion, silymarin mitigated post-weaning BPA-induced renal toxicity by suppressing ferroptosis and amyloidosis through Kim-1/Nrf2/HO-1 modulation.

E1231/SR647 protects against unilateral renal ischemia-reperfusion injury by modulating SIRT1/FOXO3 interactions with Nrf2 and NFκB pathways

Ischemia is a major contributor to acute kidney injury (AKI), for which current treatment options remain limited. One NAD+-dependent deacetylase that can preserve renal cells is SIRT1. To date, no research has directly explored the effects of E1231, a SIRT1 activator, in the context of renal ischemia-reperfusion (IR) injury. Enhancing NAD+ levels is essential for sustaining SIRT1 activity. Hence, the combined use of E1231 and SR647, a NAD+ precursor, could potentially amplify protective effects by supporting prolonged SIRT1 activation. This study is the first to investigate the therapeutic potential of combining E1231 and SR647 in mitigating unilateral renal IR injury. Rats treated with E1231/SR647 effectively demonstrated reduced tubular damage, inflammation, and necrosis. These improvements correlated with a reduced kidney-to-body weight ratio and increased urine output and flow rate. Additionally, rats with IR injury demonstrated reductions in serum creatinine, BUN, UAER, and cystatin C, as well as urinary NGAL and both serum and urinary KIM-1 levels. On the other hand, elevations in urine creatinine and creatinine CL were recorded. E1231 alone provided moderate functional recovery, which was negated when co-administered with a SIRT1 inhibitor. E1231/SR647 treatment upregulated SIRT1 levels and activity, subsequently enhancing FOXO3 activation. It also boosted Nrf2 levels and activity, upregulating the antioxidant protein expression of HO-1 and NQO1. Furthermore, E1231/SR647 reduced the inflammatory response by inhibiting NFκB activity. In conclusion, E1231/SR647 is a promising therapy that may protect renal function during ischemic events through the modulation of SIRT1/FOXO3 control over Nrf2 and NFκB pathways.

MiR-556-3p mediated repression of klotho under oxidative stress promotes fibrosis of renal tubular epithelial cells

Chronic kidney disease (CKD) is a global health issue characterized by renal fibrosis, which leads to irreversible tissue damage. Oxidative stress plays a key role in driving the fibrotic processes associated with CKD. This study investigates the roles of oxidative stress, miR-556-3p, and klotho in renal tubular epithelial cells, focusing on their influence on fibrotic pathways. Using human renal tubular epithelial cells HK-2, we conducted various in vitro assays to measure reactive oxygen species (ROS) levels, cell death, viability, and proliferation. Oxidative stress, induced by H2O2 treatment, was found to suppress klotho expression while increasing the expression of fibrotic markers. Overexpression of klotho mitigated these effects, highlighting its protective role against oxidative stress-induced fibrosis. Moreover, miR-556-3p was upregulated in response to oxidative stress activated transcription factor Nuclear Factor Erythroid 2-Related Factor 2 (Nrf2), contributing to the suppression of klotho. Inhibition of Nrf2, a key regulator of oxidative stress responses, attenuated the expression of miR-556-3p and fibrotic markers. Targeting the Nrf2-miR-556-3p-klotho axis may offer novel therapeutic avenues to restore klotho levels and attenuate renal fibrosis. Our study contributes significantly to the understanding of the molecular mechanisms driving CKD progression and highlights potential targets for future pharmacological intervention.

Near-infrared fluorescence imaging platform with ultra large Stokes shift for monitoring and bioimaging of hydrogen peroxide in the process of ferroptosis

Hydrogen peroxide (H2O2), as a strong oxidant, is crucial for the aerobic metabolism of organisms and is intricately linked to the onset of numerous diseases. Real-time monitor H2O2 levels in the environment and biological microenvironment is of paramount importance for environment protection and elucidating H2O2-related physiological and pathological processes. In this study, a novel near-infrared fluorescence imaging platform was developed and a near-infrared fluorescent probe FBMH was constructed based on the platform with photoinduced electron transfer mechanism. A series of experiments to evaluate its spectral properties and bioimaging capabilities proved that the probe demonstrated near-infrared emission, excellent selectivity and anti-interference capability in complex environments, along with high sensitivity (LOD = 2.6 × 10-9 mol/L), large Stokes shift (220 nm) and rapid response (15 min). In addition, the detection of H2O2 in actual water samples was realized with the probe. Furthermore, the implement of bioimaging of exogenous and endogenous H2O2 in Hela cells, Raw264.7 cells, zebrafish and BALB/c nude mice, especially the visualization of H2O2 level changes in the process of ferroptosis, testified its excellent potential in monitoring H2O2 in H2O2-related diseases.

Histidine-rich glycoprotein inhibits TNF-α-induced tube formation in human vascular endothelial cells

Introduction

Tumor necrosis factor-α (TNF-α)-induced angiogenesis plays a critical role in tumor progression and metastasis, making it an important therapeutic target in cancer treatment. Suppressing angiogenesis can effectively limit tumor growth and metastasis. However, despite advancements in understanding angiogenic pathways, effective strategies to inhibit TNF-α-mediated angiogenesis remain limited.

Methods

This study investigates the antiangiogenic effects of histidine-rich glycoprotein (HRG), a multifunctional plasma protein with potent antiangiogenic properties, on TNF-α-stimulated human endothelial cells (EA.hy926). Tube formation assays were performed to assess angiogenesis, and gene/protein expression analyses were conducted to evaluate HRG's effects on integrins αV and β8. The role of nuclear factor erythroid 2-related factor 2 (NRF2) in HRG-mediated antiangiogenic activity was also examined through nuclear translocation assays and NRF2 activation studies.

Results

At physiological concentrations, HRG effectively suppressed TNF-α-induced tube formation in vitro and downregulated TNF-α-induced expression of integrins αV and β8 at both the mRNA and protein levels. HRG treatment promoted NRF2 nuclear translocation in a time-dependent manner. Furthermore, activation of NRF2 significantly reduced TNF-α-induced tube formation and integrin expression, suggesting that NRF2 plays a key role in HRG-mediated antiangiogenic effects.

Discussion and Conclusion

Our findings indicate that HRG suppresses TNF-α-induced angiogenesis by promoting NRF2 nuclear translocation and transcriptional activation, which in turn inhibits integrin αV and β8 expression. Given the essential role of angiogenesis in tumor progression, HRG's ability to regulate this process presents a promising therapeutic strategy for cancer treatment.

NRF2-mediated osteoblast anti-ferroptosis effect promotes induced membrane osteogenesis

Induced membrane technique (IMT) is a new method for repairing segmental bone defects. However, the mechanism of its defect repair is not clear. In recent years, several studies have gradually indicated that ferroptosis is closely related to bone remodeling. Therefore, this study mainly explored the impact of NRF2-mediated osteoblast anti-ferroptosis on bone mineralization within the induced membrane. Male Sprague-Dawley rats aged 12-14 weeks were randomly divided into four groups (n = 12): Model group, DMF (NRF2 agonist) group, ML385 (NRF2 inhibitor) group and Sham group. Except for Sham group, an IMT model of the right femur was established in all other groups. After 4 weeks and 8 weeks of treatment with DMF and ML385, compared to Model group, DMF group showed significantly higher levels of bone volume fraction (BV/TV), osteogenic factors and NRF2/ARE pathway-related factors (NRF2, GPX4, HO-1 and SLC7A11), while ferroptosis-related indicators (total iron, 4-HNE and MDA) were significantly lower. Conversely, ML385 group exhibited significantly higher ferroptosis-related indicators and lower levels of NRF2/ARE pathway-related factors and osteogenesis. In vitro, erastin could induce ferroptosis in osteoblasts. Compared to Erastin group, Erastin+oe-NRF2 (NRF2 overexpression) group showed significantly increased cell viability, mineralization ability, and levels of NRF2/ARE pathway-related factors, along with reduced ferroptosis effects. However, Erastin+si-NRF2 (NRF2 small interfering) group displayed enhanced ferroptosis effects and significantly reduced cell viability, mineralization ability, and levels of NRF2/ARE pathway-related factors. In conclusion, in the bone grafting area of the induced membrane, there existed ferroptosis caused by iron overload. Activating the anti-ferroptosis effect of osteoblasts mediated by the NRF2/ARE signaling cascade could promote growth and mineralization of bone grafts within the induced membrane.

Low-Frequency Cyclic Stretch Upregulates the Expression of Nuclear Factor Erythroid 2-Related Factor 2 in Human Nucleus Pulposus Cells to Inhibit the Resistin-Induced Interleukin-20 Expression

Background

Resistin may connect obesity and intervertebral disc (IVD) degeneration (IDD) and is linked with chronic inflammation. Furthermore, human IDD is characterized by high expression of interleukin-20 (IL-20). The response of human nucleus pulposus (NP) cells to tensile forces depends on both the duration and magnitude of the force applied. Nonetheless, the interactions among resistin, IL-20, and tensile forces in regulating the function of IVD NP cells remain yet to be fully understood. Nuclear factor erythroid 2-related factor 2 (NRF2) has been identified as a pleiotropic protein that enhances cellular resistance to stress stimuli and inflammatory challenges. The role of NRF2 in NP cells is not well defined, and whether tensile force influences NRF2 levels in NP cells is not known.

Aims

This study investigated the role of NRF2 in human NP cells subjected to low-frequency cyclic stretch stimulation, and the underlying mechanisms involved.

Materials and Methods

Human NP cells were cultured in chambers, serum-starved for 12 h, then subjected to 5% cyclic strain at 0.1 Hz in a bioreactor. Control chambers had no stretching. Cells were lysed for analysis post-loading.

Results

Resistin stimulation induced the expression of IL-20 in human NP cells in a dose- and time-dependent manner. The activation of the p38 mitogen-activated protein kinase, and Akt signaling pathways, as well as the production of toll-like receptor 4, are necessary to render resistin to cause the release of IL-20. In NP cells, transcription factor enzyme-linked immunosorbent assays revealed that resistin led to an increase in nuclear factor (NF)-κB-DNA binding activities. Exposure of NP cells to 5% cyclic stretch at 0.1 Hz inhibited this resistin-induced NF-κB activation and IL-20 expression.

Discussion

These findings elucidate the molecular mechanisms through which resistin induces IL-20 expression in NP cells and also demonstrate that low-frequency cyclic stretch can protect against this induction.

Development of an Oxygen-Insensitive Nrf2 Reporter Reveals Redox Regulation under Physiological Normoxia

Reactive oxygen species, particularly hydrogen peroxide (H2O2), play crucial roles in cellular signaling, with Nrf2 serving as a key transcription factor in maintaining redox homeostasis. However, the precise influence of H2O2 on Nrf2 activity under physiological normoxia remains unclear due to the limitations of oxygen-sensitive imaging methods. To address this, we developed and validated an oxygen-insensitive Nrf2 reporter named pericellular oxygen-insensitive Nrf2 transcriptional performance reporter (POINTER). We employed this reporter in human cerebral microvascular endothelial cells (hCMEC/D3). Using POINTER, we investigated how varying intracellular H2O2 concentrations affect Nrf2 regulation under normoxia (5 kPa O2) compared to hyperoxia (ambient air, 21 kPa O2). We manipulated intracellular H2O2 levels through exogenous application, chemogenetic production using a modified amino acid oxidase, and pharmacological induction with Auranofin. Our findings reveal that Nrf2 transcriptional activity is significantly lower under normoxia than under hyperoxia, supporting previous literature and expectations. Using POINTER, we found that both antioxidant pathway inhibition and sustained H2O2 elevation are essential for modulating Nrf2 activity. These findings provide new insights into the regulation of Nrf2 by H2O2.

Selenium Mitigates Caerulein and LPS-induced Severe Acute Pancreatitis by Inhibiting MAPK, NF-κB, and STAT3 Signaling via the Nrf2/HO-1 Pathway

Severe acute pancreatitis (SAP) leads to systemic inflammation, resulting in multiorgan damage. Acute lung injury and acute respiratory distress syndrome develop in one-third of SAP patients, with a high mortality rate of 60% due to secondary complications. Patients with pancreatitis often have selenium deficiency, and selenium supplements may provide beneficial effects. This study examined the protective role of selenium in a model of SAP induced by caerulein + lipopolysaccharide (cae + LPS). Mice were administered selenium (1 mg/kg) before being challenged with caerulein (6 injections of 50 μg/kg) and LPS (10 mg/kg). At 3 h after the last caerulein injection, blood was collected for estimating pancreatic enzymes and cytokine levels, and the mice were euthanized. We performed morphological and histological studies, measured levels of protease and oxidative stress markers and conducted western blot, ELISA, and RT-qPCR analyses. We examined lung tissue histologically and estimated myeloperoxidase levels. Selenium pretreatment significantly reduced pancreatic enzyme levels such as amylase, lipase, and proteases (specifically MMPs) and reversed tissue injury in the pancreas and lungs caused by cae + LPS. In addition, selenium-treated mice showed decreased levels of inflammatory markers and chemokines. Examination of the downstream inflammatory pathways confirmed the protective effect of selenium, which mediates its anti-inflammatory and antioxidant action by inhibiting the major inflammatory signaling pathways (MAPKs, NF-κB, and STAT3) and activating the phosphorylation of Nrf2 via Nrf2/HO-1 pathways. These findings suggest that selenium may be a potential therapeutic option for treating SAP-associated secondary complications.

The Analysis and Comparison of Anti-Inflammatory and Antioxidant Characteristics of Postbiotic and Paraprobiotic Derived From Novel Native Probiotic Cocktail in DSS-Induced Colitic Mice

Oxidative stress, particularly when precipitated by the intake of a diet rich in fats, has the potential to induce an inflammatory state. Therefore, it is crucial to consider the administration of agents possessing antioxidant and anti-inflammatory properties for the benefit of these patients. The objective of this study was to investigate the ability of postbiotic and paraprobiotic substances to regulate oxidative stress and inflammation. We hypothesized that both postbiotics and paraprobiotics could demonstrated significant efficacy in reducing oxidative stress and inflammation, with distinct differences in their effectiveness. A total of 88 Lactobacillus and Bifidobacterium strains were assessed for antioxidant activity. Male C57BL/6 mice were divided into four groups: HFD + PBS, HFD + DSS, HFD + DSS + postbiotic, and HFD + DSS + paraprobiotic. Various parameters, including weight change, disease activity index, and gene expression analysis, as well as enzymes involved in oxidative activities and inflammation were evaluated after treatment with derivatives of six selected strains. In comparison with the groups exposed to DSS, mice treated with a combination of postbiotic and paraprobiotic alongside DSS exhibited a reduction in DSS-induced negative effects on both phenotypical characteristics and molecular indices, particularly the Nrf2- and NF-kB-related genes, with a notable focus on postbiotic. Based on the results, it can be inferred that despite the utilization of an unhealthy regime that may worsen oxidative stress and inflammation, the condition can be efficiently controlled by employing secure variations of probiotics, such as paraprobiotic and postbiotic components, with a particular emphasis on postbiotics.

Antioxidant-Rich Functional Foods and Exercise: Unlocking Metabolic Health Through Nrf2 and Related Pathways

This article reviews the synergistic effects of antioxidant-enriched functional foods and exercise in improving metabolic health, focusing on the underlying molecular mechanisms. The review incorporates evidence from PubMed, SCOPUS, Web of Science, PsycINFO, and reference lists of relevant reviews up to 20 December 2024, highlighting the central role of the Nrf2 pathway. As a critical regulator of oxidative stress and metabolic adaptation, Nrf2 mediates the benefits of these interventions. This article presents an innovative approach to understanding the role of Nrf2 in the regulation of oxidative stress and inflammation, highlighting its potential in the prevention and treatment of various diseases, including cancer, neurodegenerative disorders, cardiovascular and pulmonary diseases, diabetes, inflammatory conditions, ageing, and infections such as COVID-19. The novelty of this study is to investigate the synergistic effects of bioactive compounds found in functional foods (such as polyphenols, flavonoids, and vitamins) and exercise-induced oxidative stress on the activation of the Nrf2 pathway. This combined approach reveals their potential to improve insulin sensitivity and lipid metabolism and reduce inflammation, offering a promising strategy for the management of chronic diseases. However, there are significant gaps in current research, particularly regarding the molecular mechanisms underlying the interaction between diet, physical activity, and Nrf2 activation, as well as their long-term effects in different populations, including those with chronic diseases. In addition, the interactions between Nrf2 and other critical signalling pathways, including AMPK, NF-κB, and PI3K/Akt, and their collective contributions to metabolic health are explored. Furthermore, novel biomarkers are presented to assess the impact of these synergistic strategies, such as the NAD+/NADH ratio, the GSH ratio, and markers of mitochondrial health. The findings provide valuable insights into how the integration of an antioxidant-rich diet and regular exercise can improve metabolic health by activating Nrf2 and related molecular pathways and represent promising strategies for the prevention and treatment of metabolic disorders. Further studies are needed to fully understand the therapeutic potential of these interventions in diseases related to oxidative stress, such as cardiovascular disease, neurodegenerative disease, diabetes, and cancer.

Antiosteoporosis and Bone Protective Effect of Phyllanthin Against Glucocorticoid-induced Osteoporosis in Rats via Alteration of HO-1/Nrf2 and RANK/RANKL/OPG Pathway

Osteoporosis is a condition where bones weaken due to a loss in density and quality, making them fragile and more susceptible to fractures, even from minor stress or injury. In this experimental study, we scrutinized the antiosteoporosis effect of phyllanthin against glycocorticoid (GIOP) induced osteoporosis in rats.

METHODS

: SD rats were used in this study and subcutaneous administration of DEX (3 mg/kg) was used for the induction of osteoporosis and rats were treated with phyllanthin and alendronate for 12 weeks. The body weight, femur mass, length, hormones, nutrients, antioxidant, cytokines and bone parameters were estimated. The mRNA expression of HO-1, Nrf2, RANK, RANKL and OPG were estimated.

RESULTS

: Phyllanthin treatment significantly (p < 0.001) improved the body weight, femur mass and femur length. Phyllanthin significantly (p < 0.001) altered the level of hormones estrodiol, PTH; nutrients such as calcium, phosphorus, magnesium; Bone mineral content (BMC) and bone mineral density (BMD); Bone formation marker like ALP, TRAP, osteocalcin, β-CTX, BGP, cathepsin K, DPD; Bone parameters viz., Tb.N, BV/TV, Tb.sp, BS/BV, Tb.Th; Bone structure analysis includes maximum load, energy, stiffness, maximum stress, young's modules; oxidative stress parameters such as TBARS, CAT, GPx, GSH, GR; cytokines such as TNF-α, IL-1β, IL-6, IL-10 and antioxidant marker such as HO-1 and Nrf2. Phyllanthin significantly (P < 0.001) altered the mRNA expression of HO-1, Nrf2, RANK, RANKL and OPG.

CONCLUSION

: On the basis of result, we can say that phyllanthin exhibited the antiosteoporosis effect against glucocorticoid-induced osteoporosis in rats via alteration of HO-1/Nrf2 and RANK/RANKL/OPG pathway.

In vitro and in silico hybrid approach to unveil triterpenoids from Helicteres hirsuta leaves as potential compounds for inhibiting Nrf2

Cancer is a leading global health concern, with over 20 million new cases and 9.7 million deaths reported in 2022. Chemotherapy remains a widely used treatment, but drug resistance, which affects up to 90% of treatment outcomes, significantly hampers its effectiveness. The transcription factor Nrf2, which is crucial for cellular defense against oxidative stress, plays a dual role in cancer treatment. Although Nrf2 activation can suppress early carcinogenesis, its overexpression in cancer cells contributes to drug resistance, resulting in poor patient outcomes. Thus, inhibiting Nrf2 has emerged as a promising strategy for overcoming cancer drug resistance. Natural compounds such as luteolin and brusatol have shown potential in inhibiting Nrf2, although with limitations. This study isolates and characterizes seven triterpenoids from the n-hexane sub-fraction of Helicteres hirsuta, a plant traditionally used for medicinal purposes, to evaluate their ability to modulate Nrf2 activity in Huh7 cancer and HaCaT normal cells. Additionally, molecular docking and dynamic simulations were utilized to assess the binding potential of these compounds to the PI3Kα receptor, which regulates downstream signaling pathways, thereby suppressing Nrf2 activity in cancer cells. Our findings provide insights into new strategies seeking triterpenoids as promising structures to reverse chemoresistance by regulating Nrf2. The results also reveal the potential of 3β-O-trans-caffeoylbetulinic acid from H. hirsuta leaves as the unprecedented compound inhibiting Nrf2 activity, with an IC50 of 74.5 μg mL-1 in Huh7 cancer cells.

n-acetyl-l-cysteine stimulates bone healing by recovering the age-associated degenerative complications relative to osteoblastic Wntless ablation

Dysregulated Wnt signaling causes age-related characteristics such as oxidative stress, stem cell senescence, and abnormal bone homeostasis. Here we explored whether supplemental n-acetyl-l-cysteine (NAC) recovers the age-associated complications relative to osteoblastic Wntless (Wls) ablation and examined the possible mechanisms therein. For this work, we administered Col2.3-Cre;Wlsfl/fl mutant and littermate control (Wlsfl/fl) mice (14 weeks of age) with NAC (40 mM)-supplemented or NAC-free water for four weeks. A proportion of these mice received non-critical-sized femoral defects at 16 weeks of age. Blood, bone, and bone marrow (BM) samples were collected and adjusted for in vivo, ex vivo, and in vitro analyses. Osteoblastic Wls deletion delayed bone mass accrual and the healing of bone defects, stimulated osteoclastic activation and inflammatory factor expression, and decreased antioxidant enzyme activity in the BM. Osteoblastic Wls deletion also promoted oxidative stress, apoptosis, and senescence in BM stromal cells (BMSCs) and decreased BMSC' multipotencies. Supplementation of Wlsfl/fl mice with NAC enhanced bone mass accrual and regenerative bone healing via a Wnt signal-associated osteogenic activation. However, supplemental NAC induced new bone formation in the mutant mice by inhibiting the age-related complications of BM/BMSCs, as well as by restoring endogenous antioxidant system without any alterations in Wnt ligand secretion, hematopoiesis, and expression of osteogenic and growth factors. This study indicates that supplemental NAC protects mice against Wnt deficiency-mediated and age-associated degenerative complications. Overall, this study highlights the therapeutic potency of NAC for restoring the antioxidant system, stem cell function, and regenerative bone homeostasis in osteoblastic Wls-dispensable manner.

Oxidative stress in critically ill neonatal foals

BACKGROUND

Oxidative injury occurs in septic people, but the role of oxidative stress and antioxidants has rarely been evaluated in foals.

OBJECTIVES/HYPOTHESIS

To measure reactive oxygen species (ROS), biomarkers of oxidative injury, and antioxidants in neonatal foals. We hypothesized that ill foals would have higher blood concentrations of ROS and biomarkers of oxidative injury and lower concentrations of antioxidants compared to healthy foals.

ANIMALS

Seventy-two hospitalized and 21 healthy neonatal foals.

METHODS

Prospective cohort study. Reactive oxygen species (hydrogen peroxide [H2O2]), biomarkers of oxidative injury (malondialdehyde [MDA], protein carbonyl), and antioxidants (superoxide dismutase [SOD], catalase [CAT], glutathione, and glutathione reductase [GR] and peroxidase [GPx]) were measured from foals at admission. Measured variables were compared between healthy and ill foals using a 1-way ANOVA by Tukey's multiple comparisons test.

RESULTS

Ill foals (n = 51) had significantly higher mean concentrations of H2O2 (healthy 2.6 ± 1.4 nmol/mL, ill 6.8 ± 4.6 L nmol/mL; 95% CI), MDA (healthy 31.2 ± 14.4 nmol/mL, ill 114.3 ± 94.0 nmol/mL; 95% CI), and protein carbonyl (healthy 0.07 ± 0.01 nmol/mg protein, ill 0.12 ± 0.02 nmol/mg protein, 95% CI). Significant lower CAT (healthy 0.4 ± 0.3 mU/mg protein, ill 0.02 ± 0.02 mU/mg protein, 95% CI), glutathione (healthy 238.5 ± 101.9 μg/mL, ill 110.7 ± 37.8 μg/mL, 95% CI; P < .0001), GR (healthy 1.6 ± 1.8 mU/mg protein, ill 0.4 ± 0.5 mU/mg protein, 95% CI), and GPx (healthy 0.01 ± 0.003 mU/mg protein, ill 0.007 ± 0.002 mU/mg protein, 95% CI) were also noted.

CONCLUSIONS AND CLINICAL IMPORTANCE

Oxidative stress and lower antioxidant concentrations occur in ill and bacteremic neonatal foals. These variables should be considered during the treatment of ill foals.

Oxidative Stress Induced by Antivirals: Implications for Adverse Outcomes During Pregnancy and in Newborns

Oxidative stress plays a critical role in various physiological and pathological processes, particularly during pregnancy, where it can significantly affect maternal and fetal health. In the context of viral infections, such as those caused by Human Immunodeficiency Virus (HIV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), oxidative stress may exacerbate complications by disrupting cellular function and immune responses. Antiviral drugs, while essential in managing these infections, can also contribute to oxidative stress, potentially impacting both the mother and the developing fetus. Understanding the mechanisms by which antivirals can contribute to oxidative stress and examination of pharmacokinetic changes during pregnancy that influence drug metabolism is essential. Some research indicates that antiretroviral drugs can induce oxidative stress and mitochondrial dysfunction during pregnancy, while other studies suggest that their use is generally safe. Therefore, concerns about long-term health effects persist. This review delves into the complex interplay between oxidative stress, antioxidant defenses, and antiviral therapies, focusing on strategies to mitigate potential oxidative damage. By addressing gaps in our understanding, we highlight the importance of balancing antiviral efficacy with the risks of oxidative stress. Moreover, we advocate for further research to develop safer, more effective therapeutic approaches during pregnancy. Understanding these dynamics is essential for optimizing health outcomes for both mother and fetus in the context of viral infections during pregnancy.

MiR-142-5p mediated Nrf2 dysregulation in gestational diabetes mellitus and its impact on placental angiogenesis

INTRODUCTION

Gestational diabetes mellitus (GDM) presents significant risks during pregnancy, including adverse perinatal outcomes and placental dysfunction. Impaired angiogenesis, involving crucial factors like Vascular Endothelial Growth Factor (VEGF), contributes to these complications. The Nrf2/Keap1 pathway, crucial for vascular redox homeostasis, has been linked to GDM-associated angiogenesis dysregulation.

METHODS

This study aimed to investigate the molecular mechanisms underlying placental Nrf2 regulation, focusing on angiomiRs, key regulators of angiogenesis in GDM. Computational analysis identified miR-142-5p targeting Nrf2 mRNA. Expression levels of miR-142-5p were assessed in GDM placenta and correlated with Nrf2 expression. Experimental validation utilized human trophoblastic cell lines (BeWo) exposed to hyperglycemic conditions, assessing the effects of anti-miR-142 transfection on Nrf2 expression and angiogenic marker levels.

RESULTS

miR-142-5p expression was significantly downregulated in GDM placenta, correlating positively with Nrf2 expression. In BeWo cells exposed to hyperglycemia, anti-miR-142 transfection notably increased Nrf2 expression alongside angiogenic marker levels, confirming the computational predictions.

DISCUSSION

Our findings highlight the pivotal role of miRNAs in GDM-associated impaired angiogenesis by modulating Nrf2 expression. Understanding these molecular mechanisms provides insights into potential therapeutic targets for improving pregnancy outcomes in GDM cases.

GLP-1 receptor agonist liraglutide alleviates kidney injury by regulating nuclear translocation of NRF2 in diabetic nephropathy

Diabetic nephropathy (DN) is a severe renal disorder that arises as a complication of diabetes. Liraglutide, an analogue of a glucagon-like peptide 1 (GLP-1) receptor agonist, has been shown to decrease diabetes-caused renal damage. Nevertheless, the complete understanding of the roles and mechanism remains unclear. In our study, diabetic rat models were created through a single intraperitoneal injection of streptozotocin (STZ). The level of fasting blood glucose, 24-h urine protein, serum creatinine (Scr) and blood urea nitrogen (BUN) were assessed. Periodic acid-Schiff (PAS) staining was applied to examine the pathological changes in renal tissues. Reactive oxygen species (ROS) formation was measured via dichloro-dihydro-fluorescein diacetate (DCFH-DA) probes. Western blot was conducted to examine the levels of oxidative stress-related and extracellular matrix (ECM)-associated proteins. The nuclear translocation of NRF2 was investigated through immunofluorescence and Western blot assays. We demonstrated that liraglutide attenuated DN-induced oxidative stress and ECM deposition in vitro and in vivo. Liraglutide exerted a reno-protective effect by promoting nuclear translocation of NRF2 in mesangial cells. ML385, an NRF2 inhibitor, counteracted the beneficial impact of liraglutide.

Urban aerosol particulate matter promotes cellular senescence through mitochondrial ROS-mediated Akt/Nrf2 downregulation in human retinal pigment epithelial cells

Urban aerosol particulate matter (UPM) is widespread in the environment, and its concentration continues to increase. Several recent studies have reported that UPM results in premature cellular senescence, but few studies have investigated the molecular basis of UPM-induced senescence in retinal pigment epithelial (RPE) cells. In this study, we primarily evaluated UPM-induced premature senescence and the protective function of nuclear factor erythroid 2-related factor 2 (Nrf2) in human RPE ARPE-19 cells. The findings indicated that UPM exposure substantially induced premature cellular senescence in ARPE-19 cells, as observed by increased β-galactosidase activity, expression levels of senescence-associated marker proteins, and senescence-associated phenotypes. Such UPM-induced senescence is associated with mitochondrial oxidative stress-mediated phosphatidylinositol 3'-kinase/Akt/Nrf2 downregulation. Sulforaphane-mediated Nrf2 activation Sulforaphane-mediated upregulation of phosphorylated Nrf2 suppressed the decrease in its target antioxidant gene, NAD(P)H quinone oxidoreductase 1, under UPM, which notably prevented ARPE-19 cells from UPM-induced cellular senescence. By contrast, Nrf2 knockdown exacerbated cellular senescence and promoted oxidative stress. Collectively, our results demonstrate the regulatory role of Nrf2 in UPM-induced senescence of RPE cells and suggest that Nrf2 is a potential molecular target.

Potential Therapeutic Effect of Sinigrin on Diethylnitrosamine-Induced Liver Cancer in Mice: Exploring the Involvement of Nrf-2/HO-1, PI3K-Akt-mTOR Signaling Pathways, and Apoptosis

Sinigrin is a glucosinolate present in plants of the family Brassicaceae and has been considered for its anticancer potential. This study examines the efficacy of sinigrin on the liver cancer caused by diethylnitrosamine (DEN) in mice through the analysis of its impact on the Nrf-2/HO-1, PI3K-Akt-mTOR, and apoptotic pathways. Development of liver cancer was induced by intraperitoneal injection at the age of 14 days with DEN (25 mg/kg) in mice. Thereafter, sinigrin was orally administered at doses of 10 and 20 mg/kg body weight per day the last 28 days. At the end of 10 weeks, mice were sacrificed and then we conducted hepatic biochemical and molecular assessments. Sinigrin reduced the serum level of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), alpha-fetoprotein (AFP), and bilirubin but increased total protein, and albumin, levels. Sinigrin increased the antioxidant enzymes (SOD, CAT, GPx, and GST) as indicated by reduced 8-OHdG, TBARS and increased glutathione. Sinigrin reduced the levels of inflammatory cytokines (IL-6, IL-1β, TNF-α, and NF-κB p65) and PI3K/AKT/mTOR signaling pathway. Sinigrin also activated the intrinsic mitochondrial apoptosis pathway mediated by p53, downregulated antiapoptotic proteins (Bcl-2), up-regulated pro-apoptosis regulatory proteins like Bax and caspase-3. All these results indicate that the protective effects of sinigrin against liver cancer are likely to be applied as an effective therapeutic agent through its antioxidant and pro-apoptotic activities.

Nrf2 pathways in neuroprotection: Alleviating mitochondrial dysfunction and cognitive impairment in aging

Mitochondrial dysfunction and cognitive impairment are widespread phenomena among the elderly, being crucial factors that contribute to neurodegenerative diseases. Nuclear factor erythroid 2-related factor 2 (Nrf2) is an important regulator of cellular defense systems, including that against oxidative stress. As such, increased Nrf2 activity may serve as a strategy to avert mitochondrial dysfunction and cognitive decline. Scientific data on Nrf2-mediated neuroprotection was collected from PubMed, Google Scholar, and Science Direct, specifically addressing mitochondrial dysfunction and cognitive impairment in older people. Search terms included "Nrf2", "mitochondrial dysfunction," "cognitive impairment," and "neuroprotection." Studies focusing on in vitro and in vivo models and clinical investigations were included to review Nrf2's therapeutic potential comprehensively. The relative studies have demonstrated that increased Nrf2 activity could improve mitochondrial performance, decrease oxidative pressure, and mitigate cognitive impairment. To a large extent, this is achieved through the modulation of critical cellular signalling pathways such as the Keap1/Nrf2 pathway, mitochondrial biogenesis, and neuroinflammatory responses. The present review summarizes the recent progress in comprehending the molecular mechanisms regarding the neuroprotective benefits mediated by Nrf2 through its substantial role against mitochondrial dysfunction and cognitive impairment. This review also emphasizes Nrf2-target pathways and their contribution to cognitive function improvement and rescue from mitochondria-related abnormalities as treatment strategies for neurodegenerative diseases that often affect elderly individuals.

Autophagy in Acute Lung Injury

Acute lung injury (ALI) is a critical condition marked by rapid-onset respiratory failure due to extensive inflammation and increased pulmonary vascular permeability, often progressing to acute respiratory distress syndrome (ARDS) with high mortality. Autophagy, a cellular degradation process essential for removing damaged organelles and proteins, plays a crucial role in regulating lung injury and repair. This review examines the protective role of autophagy in maintaining cellular function and reducing inflammation and oxidative stress in ALI. It underscores the necessity of precise regulation to fully harness the therapeutic potential of autophagy in this context. We summarize the mechanisms by which autophagy influences lung injury and repair, discuss the interplay between autophagy and apoptosis, and examine potential therapeutic strategies, including autophagy inducers, targeted autophagy signaling pathways, antioxidants, anti-inflammatory drugs, gene editing, and stem cell therapy. Understanding the role of autophagy in ALI could lead to novel interventions for improving patient outcomes and reducing mortality rates associated with this severe condition.

Targeting ROS-sensing Nrf2 potentiates anti-tumor immunity of intratumoral CD8+ T and CAR-T cells

Cytotoxic T lymphocytes (CTLs) play a crucial role in cancer rejection. However, CTLs encounter dysfunction and exhaustion in the immunosuppressive tumor microenvironment (TME). Although the reactive oxygen species (ROS)-rich TME attenuates CTL function, the underlying molecular mechanism remains poorly understood. The nuclear factor erythroid 2-related 2 (Nrf2) is the ROS-responsible factor implicated in increasing susceptibility to cancer progression. Therefore, we examined how Nrf2 is involved in anti-tumor responses of CD8+ T and chimeric antigen receptor (CAR) T cells in the ROS-rich TME. Here, we demonstrated that tumor growth in Nrf2-/- mice was significantly controlled and was reversed by T cell depletion and further confirmed that Nrf2 deficiency in T cells promotes anti-tumor responses using an adoptive transfer model of antigen-specific CD8+ T cells. Nrf2-deficient CTLs are resistant to ROS, and their effector functions are sustained in the TME. Furthermore, Nrf2 knockdown in human CAR-T cells enhanced the survival and function of intratumoral CAR-T cells in a solid tumor xenograft model and effectively controlled tumor growth. ROS-sensing Nrf2 inhibits the anti-tumor T cell responses, indicating that Nrf2 may be a potential target for T cell immunotherapy strategies against solid tumors.

Advance in Nrf2 Signaling Pathway in Leishmaniasis

One of the main components of innate defense against invasive parasites is oxidative stress, which is brought on by reactive oxygen species (ROS). On the other hand, oxidative stressors serve two purposes: free radicals aid in the elimination of pathogens, but they can also set off inflammation, which leads to tissue damage. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that controls the expression of numerous genes involved in the body's defense against oxidative stress brought on by aging, inflammation, tissue damage, and other pathological consequences. From cutaneous to visceral forms, Leishmania parasites invade macrophages and cause a wide range of human pathologies. Leishmania parasites have a wide range of adaptive mechanisms that disrupt several macrophage functions by altering host signaling pathways. An increasing amount of data are corroborating the idea that one of the primary antioxidant routes to counteract this oxidative burst against parasites is NRF2 signaling, which also interferes with immune responses. The nature and potency of the host immune response, as well as interactions between the invading Leishmania spp., will ascertain the course of infection and the parasites' eventual survival or eradication. The molecular processes via which Nrf2 coordinates such intricate networks comprising various pathways remain to be completely understood. In light of NRF2's significant contribution to oxidative stress, we examine the NRF2 antioxidant pathway's activation mechanism in Leishmania infection in this review. Thus, this review will examine the relationship between Nrf2 signaling and leishmaniasis, as well as explore potential therapeutic strategies for modifying this system.

SMAR1 and p53-regulated lncRNA RP11-431M3.1 enhances HIF1A translation via miR-138 in colorectal cancer cells under oxidative stress

Eukaryotic cells respond to stress by altering coding and non-coding gene expression programs. Alongside many approaches and regulatory mechanisms, long non-coding RNAs (lncRNA) are finding a significant place in gene regulation, suggesting an involvement in various cellular processes and pathophysiology. LncRNAs are regulated by many transcription factors, including SMAR1 and p53, which are tumor suppressor genes. SMAR1 inhibits cancer cell metastasis and invasion and is also known to inhibit apoptosis during low-dose stress in coordination with p53. Data mining analysis suggested that these tumor suppressor genes might coregulate the lncRNA RP11-431M3.1 in colon cancer cells. Importantly, RP11-431M3.1 expression was found to be negatively correlated with patient survival rates in a number of cancers. Oxidative stress occurs when an imbalance in the body is caused by reactive oxygen species (ROS). This imbalance is known to be important in the development/pathogenesis of colon cancer. We are researching the role and control of this lncRNA in HCT116 cells under conditions of oxidative stress. We observed a dose-dependent differential expression of lncRNA upon H2O2 treatment and found that p53 and SMAR1 bind differentially to the promoter in response to the dose of stress inducer used. RP11-431M3.1 was observed to sponge miR-138 which has an important target gene, hypoxia-inducible factor (HIF1A). miR-138 was observed to bind differentially to RP11-431M3.1 and HIF1A RNA depending on the dose of oxidative stress. Furthermore, the knockdown of RP11-431M3.1 decreased the migration and proliferation of colon cancer cells. Our results suggest a previously undescribed regulatory mechanism through which RP11-431M3.1 is transcriptionally regulated by SMAR1 and p53, target HIF1A through miR-138, and highlight its potential as a therapeutic and diagnostic marker for cancer.

Nerol mitigates dexamethasone-induced skin aging by activating the Nrf2 signaling pathway in human dermal fibroblasts

Collagen and hyaluronic acid are essential components of the dermis that collaborate to maintain skin elasticity and hydration due to their unique biochemical properties and interactions within the extracellular matrix. Prolonged exposure to glucocorticoids can induce skin aging, which manifests as diminished collagen content and hyaluronic acid levels in the dermis. Nerol, a monoterpene alcohol found in essential oils, was examined in this study for its potential to counteract glucocorticoid-induced skin aging and the underlying mechanism behind its effects. Our findings reveal that non-toxic concentrations of nerol treatment can reinstate collagen content and hyaluronic acid levels in human dermal fibroblasts treated with dexamethasone. Mechanistically, nerol mitigates dexamethasone-induced oxidative stress by activating the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway. The protective effects of nerol were significantly abrogated when the Nrf2 pathway was inhibited using the specific inhibitor ML385. In conclusion, nerol protects human dermal fibroblasts against glucocorticoid-induced skin aging by ameliorating oxidative stress via activation of the Nrf2 pathway, thereby highlighting its potential as a therapeutic agent for preventing and treating glucocorticoid-induced skin aging.

Mechanical Stress-Oxidative Stress Axis: Biological Basis in the Vaginal Wall and Pelvic Floor Muscles of Rats with Simulated Birth Injury

INTRODUCTION AND HYPOTHESIS

Vaginal delivery and resulting pelvic floor muscle (PFM) dysfunction are significant risk factors for pelvic floor dysfunction (PFD). Despite this, the biological basis underlying PFD after childbirth remain unclear. This study was aimed at assessing the early response of the vaginal wall and PFM to simulated birth injury (SBI) in rats.

METHODS

Forty female Sprague-Dawley rats were divided into four groups: control (sham operation), and 1, 4, and 14 days post-injury. In the SBI groups, a catheter was inserted into the vagina with 130 g of weight attached to the end, and the balloon was inflated to 5 ml for 2 h. Evaluation of vaginal tissues and PFMs included histological, immunohistochemical, Western blot, and uniaxial biomechanical testing.

RESULTS

In the vaginal wall, the SBI group showed significantly lower COL1A1 expression and higher MMP-2 and MMP-9 expression. At 4 and 14 days post-injury, there was a significant decrease in PFM fiber area and increased collagen content. The SBI group also exhibited significant increases in the expression of Nrf2, NQO1, HO-1, and SOD-2, indicating involvement of oxidative stress in both the vaginal wall and PFMs. Protein expression of Pax7 and MyoG, as well as the number of fibers with centralized nuclei, continued to increase significantly after SBI. Additionally, the vaginal wall of the SBI group showed a decreasing trend in tensile strength and elastic modulus, with a greater ultimate strain.

CONCLUSION

Extracellular matrix remodeling, oxidative stress, decreased biomechanical properties, and muscle dysmyogenesis may collectively contribute to increased susceptibility to PFD development.

Aripiprazole, but Not Olanzapine, Alters the Response to Oxidative Stress in Fao Cells by Reducing the Activation of Mitogen-Activated Protein Kinases (MAPKs) and Promoting Cell Survival

Prolonged use of atypical antipsychotics (AAPs) is commonly associated with increased cardiovascular disease risk. While weight gain and related health issues are generally considered the primary contributors to this risk, direct interference with mitochondrial bioenergetics, particularly in the liver where these drugs are metabolized, is emerging as an additional contributing factor. Here, we compared the effects of two AAPs with disparate metabolic profiles on the response of Fao hepatoma cells to oxidative stress: olanzapine (OLA), which is obesogenic, and aripiprazole (ARI), which is not. Results showed that cells treated with ARI exhibited resistance to H2O2-induced oxidative stress, while OLA treatment had the opposite effect. Despite enhanced survival, ARI-treated cells exhibited higher apoptotic rates than OLA-treated cells when exposed to H2O2. Gene expression analysis of pro- and anti-apoptotic factors revealed that ARI-treated cells had a generally blunted response to H2O2, contrasting with a heightened response in OLA-treated cells. This was further supported by the reduced activation of MAPKs and STAT3 in ARI-treated cells in response to H2O2, whereas OLA pre-treatment enhanced their activation. The loss of stress response in ARI-treated cells was consistent with the observed increase in the mitochondrial production of O2•-, a known desensitizing factor. The physiological relevance of O2•- in ARI-treated cells was demonstrated by the increase in mitophagy flux, likely related to mitochondrial damage. Notably, OLA treatment protected proteasome activity in Fao cells exposed to H2O2, possibly due to the better preservation of stress signaling and mitochondrial function. In conclusion, this study highlights the underlying changes in cell physiology and mitochondrial function by AAPs. ARI de-sensitizes Fao cells to stress signaling, while OLA has the opposite effect. These findings contribute to our understanding of the metabolic risks associated with prolonged AAP use and may inform future therapeutic strategies.

Mitigating Hyperglycaemic Oxidative Stress in HepG2 Cells: The Role of Carica papaya Leaf and Root Extracts in Promoting Glucose Uptake and Antioxidant Defence

Background/Objectives: Diabetes often goes undiagnosed, with 60% of people in Africa unaware of their condition. Type 2 diabetes mellitus (T2DM) is associated with insulin resistance and is treated with metformin, despite the undesirable side effects. Medicinal plants with therapeutic potential, such as Carica papaya, have shown promising anti-diabetic properties. This study explored the role of C. papaya leaf and root extracts compared to metformin in reducing hyperglycaemia-induced oxidative stress and their impact on liver function using HepG2 as a reference. Methods: The cytotoxicity was assessed through the MTT assay. At the same time, glucose uptake and metabolism (ATP and ∆Ψm) in HepG2 cells treated with C. papaya aqueous leaf and root extract were evaluated using a luminometry assay. Additionally, antioxidant properties (SOD2, GPx1, GSH, and Nrf2) were measured using qPCR and Western blot following the detection of MDA, NO, and iNOS, indicators of free radicals. Results: The MTT assay showed that C. papaya extracts did not exhibit toxicity in HepG2 cells and enhanced glucose uptake compared to the hyperglycaemic control (HGC) and metformin. The glucose levels in C. papaya-treated cells increased ATP production (p < 0.05), while the ∆Ψm was significantly increased in HGR1000-treated cells (p < 0.05). Furthermore, C. papaya leaf extract upregulated GPx1 (p < 0.05), GSH, and Nrf2 gene (p < 0.05), while SOD2 and Nrf2 proteins were reduced (p > 0.05), ultimately lowering ROS (p > 0.05). Contrarily, the root extract stimulated SOD2 (p > 0.05), GPx1 (p < 0.05), and GSH levels (p < 0.05), reducing Nrf2 gene and protein expression (p < 0.05) and resulting in high MDA levels (p < 0.05). Additionally, the extracts elevated NO levels and iNOS expression (p < 0.05), suggesting potential RNS activation. Conclusion: Taken together, the leaf extract stimulated glucose metabolism and triggered ROS production, producing a strong antioxidant response that was more effective than the root extract and metformin. However, the root extract, particularly at high concentrations, was less effective at neutralising free radicals as it did not stimulate Nrf2 production, but it did maintain elevated levels of SOD2, GSH, and GPx1 antioxidants.

Palmatine Alleviates Particulate Matter-Induced Acute Lung Injury by Inhibiting Pyroptosis via Activating the Nrf2-Related Pathway

Particulate matter (PM) induces and enhances oxidative stress and inflammation, leading to a variety of respiratory diseases, including acute lung injury. Exploring new treatments for PM-induced lung injury has long been of interest to researchers. Palmatine (PAL) is a natural extract derived from plants that has been reported in many studies to alleviate inflammatory diseases. Our study was designed to explore whether PAL can alleviate acute lung injury caused by PM. The acute lung injury model was established by instilling PM (4 mg/kg) into the airway of mice, and PAL (50 mg/kg and 100 m/kg) was administrated orally as the treatment groups. The effect and mechanism of PAL treatment were examined by immunofluorescence, immunohistochemistry, Western Blotting, ELISA, and other experiments. The results showed that oral administration of PAL (50 mg/kg and 100 m/kg) could significantly alleviate lung inflammation and acute lung injury caused by PM. In terms of mechanism, we found that PAL (50 mg/kg) exerts anti-inflammatory and anti-damage effects mainly by enhancing the activation of the Nrf2-related antioxidant pathway and inhibiting the activation of the NLRP3-related pyroptosis pathway in mice. These mechanisms have also been verified in our cell experiments. Further cell experiments showed that PAL may reduce intracellular reactive oxygen species (ROS) by activating Nrf2-related pathways, thereby inhibiting the activation of NLRP3-related pyroptosis pathway induced by PM in Beas-2B cell. Our study suggests that PAL can be a new option for PM-induced acute lung injury.

Neuroprotective effects of punicalagin and/or micronized zeolite clinoptilolite on manganese-induced Parkinson's disease in a rat model: Involvement of multiple pathways

BACKGROUND

Manganism, a central nervous system dysfunction correlated with neurological deficits such as Parkinsonism, is caused by the substantial collection of manganese chloride (MnCl2) in the brain.

OBJECTIVES

To explore the neuroprotective effects of natural compounds, namely, micronized zeolite clinoptilolite (ZC) and punicalagin (PUN), either individually or in combination, against MnCl2-induced Parkinson's disease (PD).

METHODS

Fifty male albino rats were divided into 5 groups (Gps). Gp I was used as the control group, and the remaining animals received MnCl2 (Gp II-Gp V). Rats in Gps III and IV were treated with ZC and PUN, respectively. Gp V received both ZC and PUN as previously reported for the solo-treated plants.

RESULTS

ZC and/or PUN reversed the depletion of monoamines in the brain and decreased acetyl choline esterase activity, which primarily adjusted the animals' behavior and motor coordination. ZC and PUN restored the balance between glutamate/γ-amino butyric acid content and markedly improved the brain levels of brain-derived neurotrophic factor and nuclear factor erythroid 2-related factor 2/heme oxygenase-1 and decreased glycogen synthase kinase-3 beta activity. ZC and PUN also inhibited inflammatory and oxidative markers, including nuclear factor kappa-light-chain-enhancer of activated B cells, Toll-like receptor 4, nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 and caspase-1. Bcl-2-associated X-protein and B-cell leukemia/lymphoma 2 protein (Bcl-2) can significantly modify caspase-3 expression. ZC and/or PUN ameliorated PD in rats by decreasing the levels of endoplasmic reticulum (ER) stress markers (p-protein kinase-like ER kinase (PERK), glucose-regulated protein 78, and C/EBP homologous protein (CHOP)) and enhancing the levels of an autophagy marker (Beclin-1).

DISCUSSION AND CONCLUSION

ZC and/or PUN mitigated the progression of PD through their potential neurotrophic, neurogenic, anti-inflammatory, antioxidant, and anti-apoptotic activities and by controlling ER stress through modulation of the PERK/CHOP/Bcl-2 pathway.

Radiation research trends by young scientists and the future tasks in Northern Japan: report on 'the 10th educational symposium on radiation and health (ESRAH) by young scientists in 2023'

PURPOSE

Since 2014, an educational activity on radiation and health in northern Japan has been carried out by young scientists, the so-called 'Educational Symposium on Radiation and Health (ESRAH)'. Close cooperation has been continued in preparing for any possible emergency response to radiation accidents because several facilities, e.g., the Tomari Nuclear Power Plant in Hokkaido and the Low-Level Radioactive Waste Disposal Facility in Aomori prefecture. The ESRAH meeting has provided informational exchange and discussion forum on a broad range of subjects in various. In 2023, the 10th Memorial ESRAH meeting took place to boost scientific understanding and multidisciplinary collaborations for young scientists. Herein, we report on the ESRAH2023 symposium and analyze the research categories of young scientists from the past 10-year presentations.

CONCLUSIONS

To date, the ESRAH meeting has successfully provided a chance for multi-disciplinary research, which accounted for 27% of the total despite the COVID-19 pandemic. We found that the fraction of multi-disciplinary research in 2023 was the highest during 10-year ESRAH meetings. Meanwhile, amongst the research categories, physics, chemistry, and pharmacological studies were indicated to be less for young scientists. It is desired that further collaboration between physics, chemistry, and pharmacology in addition to the current fields would not only clarify radiation effects on the human body but also promote emergency medical care for radiation exposure in the future.

Sitagliptin exhibits protective effects against methotrexate-induced testicular toxicity: The involvement of oxidative stress-related factors

Methotrexate (MTX) is widely prescribed to treat different malignancies as well as autoimmune diseases. However, it causes a range of side effects in different organs such as testis. This study aims to clarify the role of dipeptidyl peptidase 4 (DPP4) in MTX-induced testicular damage via pathways involved in oxidative stress and evaluates the protective effects of sitagliptin as a DPP4 inhibitor. Twenty-four animals randomly allocated into four groups including: (I) control, (II) MTX (20 mg/kg, i.p.), (III) sitagliptin (20 mg/kg, i.p., for four consecutive days), and MTX + sitagliptin in which received chemicals resembling group II and III. Histopathological examinations conducted to assess the structural changes in testes of different experimental groups. Also, ELISA method employed to investigate the levels of DPP4, AKT, p-AKT, nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1). In addition, the total malondialdehyde (MDA) content and the activity of superoxide dismutase (SOD) were assessed. The results indicated that MTX administration was accompanied with testicular damage, which reversed by sitagliptin treatment. The biochemical observations demonstrated that MTX markedly increased the levels of DPP4, decreased p-AKT/AKT ratio followed by a marked decrement in Nrf2 and HO-1 levels. Also, it was observed that MTX decreased the activity of SOD and increased total MDA content in testicular specimen. However, sitagliptin treatment diminished mentioned alterations effectively. Altogether, our findings supported the possible role of DPP4 in MTX-induced testicular toxicity along with the potential protective features of sitagliptin via suppressing of the histopathological and biochemical alterations induced by MTX.

Berberine Inhibits Ferroptosis and Stabilizes Atherosclerotic Plaque through NRF2/SLC7A11/GPX4 Pathway

OBJECTIVE

To investigate potential mechanisms of anti-atherosclerosis by berberine (BBR) using ApoE-/- mice.

METHODS

Eight 8-week-old C57BL/6J mice were used as a blank control group (normal), and 56 8-week-old AopE-/- mice were fed a high-fat diet for 12 weeks, according to a completely random method, and were divided into the model group, BBR low-dose group (50 mg/kg, BBRL), BBR medium-dose group (100 mg/kg, BBRM), BBR high-dose group (150 mg/kg, BBRH), BBR+nuclear factor erythroid 2-related factor 2 (NRF2) inhibitor group (100 mg/kg BBR+30 mg/kg ML385, BBRM+ML385), NRF2 inhibitor group (30 mg/kg, ML385), and positive control group (2.5 mg/kg, atorvastatin), 8 in each group. After 4 weeks of intragastric administration, samples were collected and serum, aorta, heart and liver tissues were isolated. Biochemical kits were used to detect serum lipid content and the expression levels of malondialdehyde (MDA) and superoxide dismutase (SOD) in all experimental groups. The pathological changes of atherosclerosis (AS) were observed by aorta gross Oil Red O, aortic sinus hematoxylin-eosin (HE) and Masson staining. Liver lipopathy was observed in mice by HE staining. The morphology of mitochondria in aorta cells was observed under transmission electron microscope. Flow cytometry was used to detect reactive oxygen species (ROS) expression in aorta of mice in each group. The content of ferrous ion Fe2+ in serum of mice was detected by biochemical kit. The mRNA and protein relative expression levels of NRF2, glutathione peroxidase 4 (GPX4) and recombinant solute carrier family 7 member 11 (SLC7A11) were detected by quantitative real time polymerase chain reaction (RT-qPCR) and Western blot, respectively.

RESULTS

BBRM and BBRH groups delayed the progression of AS and reduced the plaque area (P<0.01). The characteristic morphological changes of ferroptosis were rarely observed in BBR-treated AS mice, and the content of Fe2+ in BBR group was significantly lower than that in the model group (P<0.01). BBR decreased ROS and MDA levels in mouse aorta, increased SOD activity (P<0.01), significantly up-regulated NRF2/SLC7A11/GPX4 protein and mRNA expression levels (P<0.01), and inhibited lipid peroxidation. Compared with the model group, the body weight, blood lipid level and aortic plaque area of ML385 group increased (P<0.01); the morphology of mitochondria showed significant ferroptosis characteristics; the serum Fe2+, MDA and ROS levels increased (P<0.05 or P<0.01), and the activity of SOD decreased (P<0.01). Compared with BBRM group, the iron inhibition effect of BBRM+ML385 group was significantly weakened, and the plaque area significantly increased (P<0.01).

CONCLUSION

Through NRF2/SLC7A11/GPX4 pathway, BBR can resist oxidative stress, inhibit ferroptosis, reduce plaque area, stabilize plaque, and exert anti-AS effects.

A Descriptive Review of the Antioxidant Effects and Mechanisms of Action of Berberine and Silymarin

Oxidative stress is a key factor in the development of chronic diseases such as type 2 diabetes, cardiovascular diseases, and liver disorders. Antioxidant therapies that target oxidative damage show significant promise in preventing and treating these conditions. Berberine, an alkaloid derived from various plants in the Berberidaceae family, enhances cellular defenses against oxidative stress through several mechanisms. It activates the AMP-activated protein kinase (AMPK) pathway, which reduces mitochondrial reactive oxygen species (ROS) production and improves energy metabolism. Furthermore, it boosts the activity of key antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), thus protecting cells from oxidative damage. These actions make berberine effective in managing diseases like type 2 diabetes, cardiovascular conditions, and neurodegenerative disorders. Silymarin, a flavonolignan complex derived from Silybum marianum, is particularly effective for liver protection. It activates the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, enhancing antioxidant enzyme expression and stabilizing mitochondrial membranes. Additionally, silymarin reduces the formation of ROS by chelating metal ions, and it also diminishes inflammation. This makes it beneficial for conditions like non-alcoholic fatty liver disease (NAFLD) and alcohol-related liver disorders. This review aims to highlight the distinct mechanisms by which berberine and silymarin exert their antioxidant effects.

Analytical Methods for Assessing Thiol Antioxidants in Biological Fluids: A Review

Redox metabolism is an integral part of the glutathione system, encompassing reduced and oxidized glutathione, hydrogen peroxide, and associated enzymes. This core process orchestrates a network of thiol antioxidants like thioredoxins and peroxiredoxins, alongside critical thiol-containing proteins such as mercaptoalbumin. Modifications to thiol-containing proteins, including oxidation and glutathionylation, regulate cellular signaling influencing gene activities in inflammation and carcinogenesis. Analyzing thiol antioxidants, especially glutathione, in biological fluids offers insights into pathological conditions. This review discusses the analytical methods for biothiol determination, mainly in blood plasma. The study includes all key methodological aspects of spectroscopy, chromatography, electrochemistry, and mass spectrometry, highlighting their principles, benefits, limitations, and recent advancements that were not included in previously published reviews. Sample preparation and factors affecting thiol antioxidant measurements are discussed. The review reveals that the choice of analytical procedures should be based on the specific requirements of the research. Spectrophotometric methods are simple and cost-effective but may need more specificity. Chromatographic techniques have excellent separation capabilities but require longer analysis times. Electrochemical methods enable real-time monitoring but have disadvantages such as interference. Mass spectrometry-based approaches have high sensitivity and selectivity but require sophisticated instrumentation. Combining multiple techniques can provide comprehensive information on thiol antioxidant levels in biological fluids, enabling clearer insights into their roles in health and disease. This review covers the time span from 2010 to mid-2024, and the data were obtained from the SciFinder® (ACS), Google Scholar (Google), PubMed®, and ScienceDirect (Scopus) databases through a combination search approach using keywords.

The Aryl Hydrocarbon Receptor and Its Crosstalk: A Chemopreventive Target of Naturally Occurring and Modified Phytochemicals

The aryl hydrocarbon receptor (AhR) is an environmentally sensitive transcription factor (TF) historically associated with carcinogenesis initiation via the activation of numerous carcinogens. Nowadays, the AhR has been attributed to multiple endogenous functions to maintain cellular homeostasis. Moreover, crosstalk, often reciprocal, has been found between the AhR and several other TFs, particularly estrogen receptors (ERs) and nuclear factor erythroid 2-related factor-2 (Nrf2). Adequate modulation of these signaling pathways seems to be an attractive strategy for cancer chemoprevention. Several naturally occurring and synthetically modified AhR or ER ligands and Nrf2 modulators have been described. Sulfur-containing derivatives of glucosinolates, such as indole-3-carbinol (I3C), and stilbene derivatives are particularly interesting in this context. I3C and its condensation product, 3,3'-diindolylmethane (DIM), are classic examples of blocking agents that increase drug-metabolizing enzyme activity through activation of the AhR. Still, they also affect multiple essential signaling pathways in preventing hormone-dependent cancer. Resveratrol is a competitive antagonist of several classic AhR ligands. Its analogs, with ortho-methoxy substituents, exert stronger antiproliferative and proapoptotic activity. In addition, they modulate AhR activity and estrogen metabolism. Their activity seems related to a number of methoxy groups introduced into the stilbene structure. This review summarizes the data on the chemopreventive potential of these classes of phytochemicals, in the context of AhR and its crosstalk modulation.

Activated THP-1 Macrophage-Derived Factors Increase the Cytokine, Fractalkine, and EGF Secretions, the Invasion-Related MMP Production, and Antioxidant Activity of HEC-1A Endometrium Cells

Endometrium receptivity is a multifactor-regulated process involving progesterone receptor-regulated signaling, cytokines and chemokines, and additional growth regulatory factors. In the female reproductive system, macrophages have distinct roles in the regulation of receptivity, embryo implantation, immune tolerance, and angiogenesis or oxidative stress. In the present study, we investigated the effects of PMA-activated THP-1 macrophages on the receptivity-related genes, cytokines and chemokines, growth regulators, and oxidative stress-related molecules of HEC-1A endometrium cells. We established a non-contact co-culture in which the culture medium of the PMA-activated macrophages exhibiting the pro-inflammatory phenotype was used for the treatment of the endometrial cells. In the endometrium cells, the expression of the growth-related factors activin and bone morphogenetic protein 2, the growth hormone EGF, and the activation of the downstream signaling molecules pERK1/2 and pAkt were analyzed by ELISA and Western blot. The secretions of cytokines and chemokines, which are involved in the establishment of endometrial receptivity, and the expression of matrix metalloproteinases implicated in invasion were also determined. Based on the results, the PMA-activated THP-1 macrophages exhibiting a pro-inflammatory phenotype may play a role in the regulation of HEC-1A endometrium cells. They alter the secretion of cytokines and chemokines, as well as the protein level of MMPs of HEC-1A cells. Moreover, activated THP-1 macrophages may elevate oxidative stress protection of HEC-1A endometrium cells. All these suggest that pro-inflammatory macrophages have a special role in the regulation of receptivity-related and implantation-related factors of HEC-1A cells.

Role of Oxidative Stress Signaling, Nrf2, on Survival and Stemness of Human Adipose-Derived Stem Cells Exposed to X-rays, Protons and Carbon Ions

Some cancers have a poor prognosis and often lead to local recurrence because they are resistant to available treatments, e.g., glioblastoma. Attempts have been made to increase the sensitivity of resistant tumors by targeting pathways involved in the resistance and combining it, for example, with radiotherapy (RT). We have previously reported that treating glioblastoma stem cells with an Nrf2 inhibitor increases their radiosensitivity. Unfortunately, the application of drugs can also affect normal cells. In the present study, we aim to investigate the role of the Nrf2 pathway in the survival and differentiation of normal human adipose-derived stem cells (ADSCs) exposed to radiation. We treated ADSCs with an Nrf2 inhibitor and then exposed them to X-rays, protons or carbon ions. All three radiation qualities are used to treat cancer. The survival and differentiation abilities of the surviving ADSCs were studied. We found that the enhancing effect of Nrf2 inhibition on cell survival levels was radiation-quality-dependent (X-rays > proton > carbon ions). Furthermore, our results indicate that Nrf2 inhibition reduces stem cell differentiation by 35% and 28% for adipogenesis and osteogenesis, respectively, using all applied radiation qualities. Interestingly, the results show that the cells that survive proton and carbon ion irradiations have an increased ability, compared with X-rays, to differentiate into osteogenesis and adipogenesis lineages. Therefore, we can conclude that the use of carbon ions or protons can affect the stemness of irradiated ADSCs at lower levels than X-rays and is thus more beneficial for long-time cancer survivors, such as pediatric patients.

The Antinociceptive Role of Nrf2 in Neuropathic Pain: From Mechanisms to Clinical Perspectives

Neuropathic pain, a chronic condition resulting from nerve injury or dysfunction, presents significant therapeutic challenges and is closely associated with oxidative stress and inflammation, both of which can lead to mitochondrial dysfunction. The nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, a critical cellular defense mechanism against oxidative stress, has emerged as a promising target for neuropathic pain management. Nrf2 modulators enhance the expression of antioxidant and cytoprotective genes, thereby reducing oxidative damage, inflammation, and mitochondrial impairment. This review explores the antinociceptive effects of Nrf2, highlighting how pharmacological agents and natural compounds may be used as potential therapeutic strategies against neuropathic pain. Although preclinical studies demonstrate significant pain reduction and improved nerve function through Nrf2 activation, several clinical challenges need to be addressed. However, emerging clinical evidence suggests potential benefits of Nrf2 modulators in several conditions, such as diabetic neuropathy and multiple sclerosis. Future research should focus on further elucidating the molecular role of Nrf2 in neuropathic pain to optimize its modulation efficacy and maximize clinical utility.

Unraveling the mechanistic interplay of mediators orchestrating the neuroprotective potential of harmine

Neurodegenerative diseases (NDDs) encompass a range of conditions characterized by the specific dysfunction and continual decline of neurons, glial cells, and neural networks within the brain and spinal cord. The majority of NDDs exhibit similar underlying causes, including oxidative stress, neuroinflammation, and malfunctioning of mitochondria. Elevated levels of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), alongside decreased expression of brain-derived neurotrophic factor (BDNF) and glutamate transporter subtype 1 (GLT-1), constitute significant factors contributing to the pathogenesis of NDDs. Additionally, the dual-specificity tyrosine phosphorylation-regulated kinase 1 A (DYRK1A) gene has emerged as a significant target for the treatment of NDDs at the preclinical level. It significantly contributes to developmental brain defects, early onset neurodegeneration, neuronal loss, and dementia in Down syndrome. Moreover, an impaired ubiquitin-proteosome system (UPS) also plays a pathological role in NDDs. Malfunctioning of UPS leads to abnormal protein buildup or aggregation of α-synuclein. α-Synuclein is a highly soluble unfolded protein that accumulates in Lewy bodies and Lewy neurites in Parkinson's disease and other synucleinopathies. Recent research highlights the promising potential of natural products in combating NDDs relative to conventional therapies. Alkaloids have emerged as promising candidates in the fight against NDDs. Harmine is a tricyclic β-carboline alkaloid (harmala alkaloid) with one indole nucleus and a six-membered pyrrole ring. It is extracted from Banisteria caapi and Peganum harmala L. and exhibits diverse pharmacological properties, encompassing neuroprotective, antioxidant, anti-inflammatory, antidepressant, etc. Harmine has been reported to mediate its neuroprotective via reducing the level of inflammatory mediators, NADPH oxidase, AChE, BChE and reactive oxygen species (ROS). Whereas, it has been observed to increase the levels of BDNF, GLT-1 and anti-oxidant enzymes, along with protein kinase-A (PKA)-mediated UPS activation. This review aims to discuss the mechanistic interplay of various mediators involved in the neuroprotective effect of harmine.

The Double-Edged Sword of ROS in Muscle Wasting and COPD: Insights from Aging-Related Sarcopenia

An elevation in reactive oxygen species (ROS) is widely accepted to be a key mechanism that drives chronic obstructive pulmonary disease (COPD) and its major co-morbidity, skeletal muscle wasting. However, it will be perhaps a surprise to many that an elevation in ROS in skeletal muscle is also a critical process for normal skeletal muscle function and in the adaptations to physical exercise. The key message here is that ROS are not solely detrimental. This duality of ROS suggests that the mere use of a broad-acting antioxidant is destined to fail in alleviating skeletal muscle wasting in COPD because it will also be influencing critical physiological ROS-dependent processes. Here, we take a close look at this duality of ROS in skeletal muscle physiology and pathophysiology pertaining to COPD and will aim to gain critical insights from other skeletal muscle wasting conditions due to aging such as sarcopenia.

The efficacy of curcumin supplementation on serum total antioxidant capacity, malondialdehyde, and disease activity in women with rheumatoid arthritis: A randomized, double-blind, placebo-controlled clinical trial

Oxidative stress plays a crucial role in the physiopathology of rheumatoid arthritis (RA), which is associated with impaired antioxidant defenses. This study aimed to investigate the effects of curcumin supplementation on serum levels of total antioxidant capacity (TAC), malondialdehyde (MDA), and disease activity in women with RA. In this clinical trial, 48 women with RA were treated with one capsule of curcumin (500 mg daily) or placebo for 8 weeks. Anthropometric measurements and fasting blood samples were collected at baseline and end of the study. Finally, we assessed the Disease Activity Score in 28 joints (DAS-28), dietary intake, and physical activity levels. While curcumin supplementation for 8 weeks significantly increased the serum levels of TAC (p < 0.05), it decreased tender joint counts, swollen joint counts, visual analog scale (VAS) for pain, and DAS-28 compared to the placebo at the end of the study (p < 0.001 for all). MDA levels significantly decreased in the curcumin group (p < 0.05). However, changes in MDA concentration were not significant between groups at the end of the trial (p = 0.145). Curcumin supplementation had a beneficial effect on increasing the serum levels of TAC and decreased DAS-28 in women with RA.

The role of Nrf2 signaling in parasitic diseases and its therapeutic potential

In response to invading parasites, one of the principal arms of innate immunity is oxidative stress, caused by reactive oxygen species (ROS). However, oxidative stresses play dual functions in the disease, whereby free radicals promote pathogen removal, but they can also trigger inflammation, resulting in tissue injuries. A growing body of evidence has strongly supported the notion that nuclear factor erythroid 2-related factor 2 (NRF) signaling is one of the main antioxidant pathways to combat this oxidative burst against parasites. Given the important role of NRF2 in oxidative stress, in this review, we investigate the activation mechanism of the NRF2 antioxidant pathway in different parasitic diseases, such as malaria, leishmaniasis, trypanosomiasis, toxoplasmosis, schistosomiasis, entamoebiasis, and trichinosis.

Inhibiting SIRT-2 by AK-7 restrains airway inflammation and oxidative damage promoting lung resurgence through NF-kB and MAP kinase signaling pathway

Introduction

Chronic obstructive pulmonary disease (COPD) is a major global cause of mortality with limited effective treatments. Sirtuins (SIRT) are histone deacetylases that are involved in the regulation of redox and inflammatory homeostasis. Hence, the present study aims to investigate the role of SIRT-2 in modulating inflammation in a murine model of COPD.

Methods

COPD in mice was established by cigarette smoke (CS) exposure for 60 days, and AK-7 was used as the specific SIRT-2 inhibitor. AK-7 (100 µg/kg and 200 µg/kg body weight) was administered intranasally 1 h before CS exposure. Molecular docking was performed to analyze the binding affinity of different inflammatory proteins with AK-7.

Results

Immune cell analysis showed a significantly increased number of macrophages (F4/80), neutrophils (Gr-1), and lymphocytes (CD4+, CD8+, and CD19+) in the COPD, group and their population was declined by AK-7 administration. Total reactive oxygen species, total inducible nitric oxide synthase, inflammatory mediators such as neutrophil elastase, C-reactive protein, histamine, and cytokines as IL4, IL-6, IL-17, and TNF-α were elevated in COPD and declined in the AK-7 group. However, IL-10 showed reverse results representing anti-inflammatory potency. AK-7 administration by inhibiting SIRT-2 decreased the expression of p-NF-κB, p-P38, p-Erk, and p-JNK and increased the expression of Nrf-2. Furthermore, AK-7 also declined the lung injury by inhibiting inflammation, parenchymal destruction, emphysema, collagen, club cells, and Kohn pores. AK-7 also showed good binding affinity with inflammatory proteins.

Discussion

The current study reveals that SIRT-2 inhibition mitigates COPD severity and enhances pulmonary therapeutic interventions, suggesting AK-7 as a potential therapeutic molecule for COPD medication development.

Oxidative stress induced by hydrogen peroxide disrupts zebrafish visual development by altering apoptosis, antioxidant and estrogen related genes

Hydrogen peroxide is considered deleterious molecule that cause cellular damage integrity and function. Its key redox signaling molecule in oxidative stress and exerts toxicity on a wide range of organisms. Thus, to understand whether oxidative stress alters visual development, zebrafish embryos were exposed to H2O2 at concentration of 0.02 to 62.5 mM for 7 days. Eye to body length ratio (EBR) and apoptosis in retina at 48 hpf, and optomotor response (OMR) at 7 dpf were all measured. To investigate whether hydrogen peroxide-induced effects were mediated by oxidative stress, embryos were co-incubated with the antioxidant, glutathione (GSH) at 50 μM. Results revealed that concentrations of H2O2 at or above 0.1 mM induced developmental toxicity, leading to increased mortality and hatching delay. Furthermore, exposure to 0.1 mM H2O2 decreased EBR at 48 hpf and impaired OMR visual behavior at 7 dpf. Additionally, exposure increased the area of apoptotic cells in the retina at 48 hpf. The addition of GSH reversed the effects of H2O2, suggesting the involvement of oxidative stress. H2O2 decreased the expression of eye development-related genes, pax6α and pax6β. The expression of apoptosis-related genes, tp53, casp3 and bax, significantly increased, while bcl2α expression decreased. Antioxidant-related genes sod1, cat and gpx1a showed decreased expression. Expression levels of estrogen receptors (ERs) (esr1, esr2α, and esr2β) and ovarian and brain aromatase genes (cyp19a1a and cyp19a1b, respectively) were also significantly reduced. Interestingly, co-incubation of GSH effectivity reversed the impact of H2O2 on most parameters. Overall, these results demonstrate that H2O2 induces adverse effects on visual development via oxidative stress, which leads to alter apoptosis, diminished antioxidant defenses and reduced estrogen production.

Oxidative Stress and the Nrf2/PPARγ Axis in the Endometrium: Insights into Female Fertility

Successful pregnancy depends on precise molecular regulation of uterine physiology, especially during the menstrual cycle. Deregulated oxidative stress (OS), often influenced by inflammatory changes but also by environmental factors, represents a constant threat to this delicate balance. Oxidative stress induces a reciprocally regulated nuclear factor erythroid 2-related factor 2/peroxisome proliferator-activated receptor-gamma (Nrf2/PPARγ) pathway. However, increased PPARγ activity appears to be a double-edged sword in endometrial physiology. Activated PPARγ attenuates inflammation and attenuates OS to restore redox homeostasis. However, it also interferes with physiological processes during the menstrual cycle, such as hormonal signaling and angiogenesis. This review provides an elucidation of the molecular mechanisms that support the interplay between PPARγ and OS. Additionally, it offers fresh perspectives on the Nrf2/PPARγ pathway concerning endometrial receptivity and its potential implications for infertility.