Nrf2 Gene Expression Research Articles

#4176 ROLE OF KIDNEY FUNCTION ON NRF2 MRNA LEVELS IN TYPE-2 DIABETES

Abstract Background and Aims Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that induces the expression of genes coding for antioxidant proteins and phase II detoxifying enzymes. Repressor molecule Kelch-like ECH-associated protein 1 (Keap1) and several microRNAs (miRNA) negatively regulate Nrf2 gene expression at post-transcriptional level. Oxidative stress is a major factor for kidney damage in diabetes but the role of Nrf2 in kidney dysfunction in diabetes is still unclear. Method To test whether the gene expression of Nrf-2 is downregulated in type-2 diabetes and whether kidney dysfunction per se further reduces Nrf2 in diabetic patients with diabetic nephropathy, we carried out a case-control study including 99 participants divided into three independent groups: 33 patients with diabetic nephropathy (DN), 33 patients with type 2 diabetes without nephropathy (D) and 33 control subjects (C), all accurately matched for age and sex. Standard ANOVA compared outcome measures in the three groups. Multiple linear regression analysis was used to test the expression levels of Keap1, miR-28-5p, miR-93-5p, miR-30e-5p, miR-125b-5p and miR-150-5p as potential mediators in the observed reduction of Nrf2 mRNA levels in patients with diabetic nephropathy. Results In patients with diabetic nephropathy, Nrf2 gene expression levels (0.82 arbitrary units, AU, IQR: 0.60-1.22 AU) were significantly lower than in diabetic patients without nephropathy (1.19 AU, 0.90-1.38 AU, P = 0.01) and control subjects (0.82 AU, 0.60-1.22 AU vs 1.04 AU, 0.87-1.66, P = 0.02) while there was no difference between diabetic patients without nephropathy and control subjects (P = 0.69). Keap1 gene expression levels were almost identical in patients with and without diabetic nephropathy (1.15 AU, 0.63-2.14 AU vs 1.13 AU, 0.79-1.73 AU, P = 0.91) and higher than in control subjects (1.15 AU, 0.63-2.14 AU vs 0.79 AU, 0.49-1.08 AU, P = 0.046). MiRNA expression levels were comparable in diabetic patients with and without nephropathy, but miRNA 30e-5p was lower in patients with diabetic nephropathy than in diabetic patients without nephropathy (0.91 AU, 0.76-1.10 AU vs 1.06 AU, 0.89-1.23 AU, P = 0.016). The expression levels of Nrf2 and miRNA 30e-5p were unrelated in patients with (r = 0.15, P = 0.44) and without (r = -0.02, P = 0.90) diabetic nephropathy. In linear regression analyses, eGFR emerged as the first factor in rank for explaining the difference in Nrf2 mRNA levels (explained variance 76%) among patients with and without diabetic nephropathy. Conclusion This case-control study comparing the gene expression level of Nrf2 in diabetic patients with and without nephropathy shows that kidney dysfunction is the key factor that explains the variability in Nrf2 mRNA levels in diabetes. These data suggest a primary role of Nrf2 in redox homeostasis and kidney damage in diabetic nephropathy.

NRF2/HO-1 axis, BIRC5, and TP53 expression in ESCC and its correlation with clinical pathological characteristics and prognosis.

Many types of cancer exhibit high nuclear factor erythroid 2-related factor 2 (NRF2), which is effective in resisting drugs and radiation. However, the role of NRF2 gene expression in predicting the prognosis of esophageal squamous cell carcinoma (ESCC) remains unclear. The association between NRF2, heme oxygenase-1 (HO-1), baculovirus IAP repeat 5 (BIRC5), P53 gene expression levels and their relationship to immune-infiltrating cells were assessed using the Cancer Genome Atlas dataset, the Human Protein Atlas and the TISDB database. The expression of NRF2, HO-1, BIRC5, and TP53 in 118 ESCC patients was detected by immunohistochemistry, and the relationship between their expression level and clinicopathological parameters and prognosis was analyzed. In ESCC, NRF2 overexpression was significantly associated with Han ethnicity, lymph node metastasis, and distant metastasis. HO-1 overexpression was significantly associated with differentiation, advanced clinical staging, lymph node metastasis, nerve invasion, and distant metastasis. BIRC5 overexpression was significantly associated with Han ethnicity and lymph node metastasis. TP53 overexpression was significantly associated with Han ethnicity and T staging. The NRF2/HO-1 axis expression was positively correlated with BIRC5 and TP53. Kaplan-Meier and multivariate Cox regression analysis showed that NRF2, BIRC5, and TP53 genes co-expression was an independent prognostic risk factor. TISIDB dataset analysis showed that immune-infiltrating cells were significantly negatively correlated with NRF2 and BIRC5. NRF2, BIRC5, and TP53 axis gene expressions are predictors of poor prognosis for ESCC. The overexpression of the NRF2/HO-1/BIRC5 axis may not be related to immune-infiltrating cells.

Protective effect of cafestol against doxorubicin-induced cardiotoxicity in rats by activating the Nrf2 pathway.

Doxorubicin (DOX) is an efficient antineoplastic agent with a broad antitumor spectrum; however, doxorubicin-associated cardiotoxic adverse effect through oxidative damage and apoptosis limits its clinical application. Cafestol (Caf) is a naturally occurring diterpene in unfiltered coffee with unique antioxidant, antimutagenic, and anti-inflammatory activities by activating the Nrf2 pathway. The present study aimed to investigate the potential chemoprotective effect of cafestol on DOX-induced cardiotoxicity in rats. Wistar albino rats of both sexes were administered cafestol (5mg/kg/day) for 14 consecutive days by oral gavage alone or with doxorubicin which was injected as a single dose (15mg/kg intraperitoneally at day 14) to induce toxicity. The result showed that Caf significantly improved cardiac injury induced by doxorubicin, decreased serum levels of CK-MB, LDH, ALP, and ALT, and improved histopathological changes. In addition, cafestol significantly inhibited DOX-induced cardiac oxidative stress as seen in the reduced level of MDA and increased GSH, SOD, CAT, and Gpx-1 cardiac tissue levels; cafestol significantly enhanced Nrf2 gene and protein expression and promoted the expression of downstream antioxidant genes HO-1 and NQO-1 and downregulated Keap1 and NF-κB genes' expression; in addition, Caf significantly reduced inflammatory mediators, TNF-α, and IL-1β levels and inhibited cardiac apoptosis by modulating Bax and Casp 3 tissue levels and reduced TUNEL-positive cardiomyocytes. In conclusion, the present study confirmed that cafestol improved the cardiotoxic effects induced by doxorubicin through the regulation of apoptosis and oxidative stress response through the Nrf2 pathway; this study suggests that cafestol may serve as a potential adjuvant in chemotherapy to alleviate DOX-induced toxicities.

Blastocystis sp. reduces the efficacy of 5-fluorouracil as a colorectal cancer chemotherapeutic treatment

Blastocystis is an enteric protozoan parasite with extensive genetic variation and unclear pathogenicity. It is commonly associated with gastrointestinal symptoms such as nausea, diarrhea, vomiting and abdominal pain in immunocompromised individuals. In this study, we explored the in vitro and in vivo effects of Blastocystis on the activity of a commonly used CRC chemotherapeutic agent, 5-FU. The cellular and molecular effects of solubilized antigen of Blastocystis in the presence of 5-FU were investigated using HCT116, human CRC cell line and CCD 18-Co, normal human colon fibroblast cells. For the in vivo study, 30 male Wistar rats were divided into six groups, as follows; Control Group: oral administration of 0.3 ml Jones' medium, Group A: rats injected with azoxymethane (AOM), Group A-30FU: Rats injected with AOM and administered 30 mg/kg 5-FU, Group B-A-30FU: rats inoculated with Blastocystis cysts, injected with AOM and administered 30 mg/kg 5-FU, Group A-60FU: rats injected with AOM and administered 60 mg/kg 5-FU and Group B-A-60FU: rats inoculated with Blastocystis cysts, injected with AOM and administered 60 mg/kg 5-FU. The in vitro study revealed that the inhibitory potency of 5-FU at 8 μM and 10 μM was reduced from 57.7% to 31.6% (p < 0.001) and 69.0% to 36.7% (p < 0.001) respectively when co-incubated with Blastocystis antigen for 24 h. However, the inhibitory potency of 5-FU in CCD-18Co cells was not significantly affected in the presence of Blastocystis antigen. The reduced inhibitory potency of 5-FU against cancer cell proliferation due to the presence of Blastocystis is consistent with the upregulation of expression of type 2 cytokines, transforming growth factor (TGF-β) and nuclear factor E2-related factor 2 (Nrf2) gene expression. Increased inflammation and abnormal histopathological findings along with a significant cancer multiplicity and adenoma incidence were evident in the intestine of the B-A-30FU and B-A-60FU groups when compared with the A-30FU and A-60FU groups respectively. Our in vitro and in vivo findings indicate that Blastocystis infection could potentially interfere with chemotherapy regimens such as 5-FU in CRC patients undergoing chemotherapy.

Prolactin-induced neuroprotection against excitotoxicity is mediated via PI3K/AKT and GSK3β/NF-κB in primary cultures of hippocampal neurons

Prolactin (PRL) is a polypeptide hormone that has been reported to play a significant role in neuroprotection against neuronal excitotoxicity produced by glutamate (Glu) or kainic acid (KA) in both, in vitro and in vivo models. However, the molecular mechanisms involved in PRL’s neuroprotective effects in the hippocampus have not been completely elucidated. The aim of the present study was to assess the signaling pathways involved in PRL neuroprotection against excitotoxicity. Primary rat hippocampal neuronal cell cultures were used to assess PRL-induced signaling pathway activation. The effects of PRL on neuronal viability, as well as its effects on activation of key regulatory pathways, phosphoinositide 3-kinases/Protein Kinase B (PI3K/AKT) and glycogen synthase kinase 3β / nuclear factor kappa B (GSK3β/NF-κB), were evaluated under conditions of Glutamate-induced excitotoxicity. Additionally, the effect on downstream regulated genes such as Bcl-2 and Nrf2, was assessed. Here, we show that the PI3K/AKT signaling pathway is activated by PRL treatment during excitotoxicity, promoting neuronal survival through upregulation of active AKT and GSK3β/NF-κB, resulting in induction of Bcl-2 and Nrf2 gene expression. Inhibition of the PI3K/AKT signaling pathway abrogated the protective effect of PRL against Glu-induced neuronal death. Overall, results indicate that the neuroprotective actions of PRL are mediated in part, by the activation of the AKT pathway and survival genes. Our data support the idea that PRL could be useful as a potential neuroprotective agent in different neurological and neurodegenerative diseases.

Maternal high-intensity interval training as a suitable approach for offspring's heart protection in rat: evidence from oxidative stress and mitochondrial genes.

Considerable scientific evidence suggests that the intrauterine environment plays a crucial role in determining the long-term health of offspring. The present study aims to investigate the effects of high-intensity interval training in maternal rats before and during pregnancy on the antioxidant status, mitochondrial gene expression, and anxiety-like behavior of their offspring. A total of thirty-two female rats were assigned to four maternal groups based on the timing of exercise: before pregnancy, before and during pregnancy, during pregnancy, and sedentary. The female and male offspring were allocated to groups that matched their mothers' exercise regimen. Anxiety-like behavior in the offspring was evaluated using the open-field and elevated plus-maze tests. Our findings indicate that maternal HIIT does not have any detrimental effect on the anxiety-related behavior of offspring. Also, maternal exercise before and during pregnancy could improve the general activity of the offspring. Furthermore, our results demonstrate that female offspring exhibit more locomotion activity than males. Besides, maternal HIIT leads to a reduction in the levels of TOS and MDA, while TAC levels increase, and significantly upregulate the gene expression of PGC1-α, NFR1, and NRF2 in both sexes in the heart. Therefore, our study suggests that maternal HIIT is a beneficial maternal behavior and serves as a cardioprotective agent to enhance the health of the next generations.

Dietary Coated Sodium Butyrate Ameliorates Hepatic Lipid Accumulation and Inflammation via Enhancing Antioxidative Function in Post-Peaking Laying Hens.

During the aging process of laying hens, hepatic oxidative stress damage and lipid accumulation are prone to occur, leading to the deterioration of egg quality and a decline in production properties. This research was designed to explore the effects of different levels of coated sodium butyrate (CSB) addition on oxidation resistance, inflammatory reaction, lipid metabolism and hepatic oxidative damage-related gene expression in aged laying hens. A total of 720 healthy 52 weeks old Huafeng laying hens were arbitrarily divided into 5 groups of 6 replicates with 24 birds each and fed a basal diet supplemented with 0, 250, 500, 750 and 1000 mg/kg CSB for 8 weeks, respectively. The CSB quadratically upgraded GSH-Px activities and downgraded MDA content in the liver and serum. The LDL-C, NEFA and TG contents decreased quadratically in CSB groups and significantly reduced the fatty vacuoles as well as the formation of fat granules in the liver (p < 0.05). Meanwhile, the CSB quadratically upregulated the gene expression of IL-10, Nrf2 and HO1, but downregulated the gene expression of IFN-γ, TNF-α and Keap1 in a quadratic manner (p < 0.05). Moreover, the CSB quadratically degraded the mRNA level of fatty acid synthesis but increased the gene level of key enzymes of fatty acid catabolism (p < 0.05). In conclusion, dietary CSB supplementation has a favorable effect in protecting against liver injury and alleviating lipid accumulation and inflammation by enhancing hepatic antioxidative function in aged laying hens.

Ferulic acid mitigates 2-methoxyethanol-induced testicular oxidative stress via combined downregulation of FoxO1, PTEN, and modulation of Nrf2-Hmox1-NQO1 signaling pathway in rats

IntroductionFerulic acid (FERA) is a natural antioxidant that is richly found in herbs, including Ligusticum chuangxiong, Cimicifuga heracleifolia, and female ginseng (Angelica sinensis), which are utilized in modern Chinese medicine, and in cereals/grains including rice, which is mostly consumed by humans. 2METE on the other hand, is a ubiquitous substance that has many industrial applications, including use in the preparation of dyes for textiles, hydraulic fluid for automobiles, paints, and liquid soaps. It is a testicular toxin, which can induce oxidative stress in the testis of rats. Therefore, this study investigated the effect of FERA, which was concomitantly administered, against 2-methoxyethanol (2METE)-induced testicular oxidative stress in rats. MethodsMale Wistar rats totaling twenty (20), separated into four (4) groups, were used for the study. Rats in group one served as the control, rats in groups two and three were administered 100 mg/kg of 2METE only for 30 consecutive days, but only rats in group three were concomitantly treated with 50 mg/kg of FERA for the same duration, while rats in group four were treated with 50 mg/kg of FERA only. ResultsFollowing analysis, 2METE administration caused a significant reduction in the relative testes weight (RTW), NAD(P)H quinone oxidoreductase 1 (NQO1), and reduced glutathione (GSH) levels, as well as superoxide dismutase (SOD) and glutathione S-transferase (GST) activities in the testis of rats compared with the control. Moreover, 2METE administration also significantly increased the testicular levels of malondialdehyde (MDA), nitric oxide (NO), and RNA gene expressions of heme oxygenase 1 (Hmox1), nuclear factor erythroid 2-related factor 2 (Nrf2), forkhead box protein O1 (FoxO1), and phosphatase and tensin homolog deleted on chromosome 10 (PTEN) compared with the control. FERA treatment, on the other hand, significantly decreased the testicular levels of MDA, as well as Nrf2, Hmox1, PTEN, and FoxO1 gene expressions, and significantly increased the testicular GSH and NQO1 levels, activities of GST, SOD, glutathione peroxidase (GPx), and catalase (CAT) compared with 2METE only administered rats. Conclusion2METE-induced testicular oxidative stress, marked by the depletion of the endogenous antioxidant systems, was recorded, which resulted in the activation of PTEN, FoxO1, and Nrf2 genes in rats. FERA demonstrated a strong antioxidant effect by restoring the levels and activities of the endogenous antioxidants as well as downregulating the expressions of PTEN, FoxO1, and Nrf2 in the testis of rats.

Synergistic action of carvedilol and clomiphene in mitigating the behavioral phenotypes of letrozole-model of PCOS rats by modulating the NRF2/NFKB pathway

IntroductionPsychiatric and cognitive impairment has been observed in premenopausal women with a hormonal disorder called polycystic ovary syndrome (PCOS). This study aimed to explore the possibility of combining pharmacological agents: Carvedilol and Clomiphene citrate, with antiestrogenic, antioxidant and anti-inflammatory properties in letrozole-induced PCOS rats. MethodsPCOS was induced in rats by the administration of letrozole (1 mg/kg) daily for 21 days. They were subsequently divided into four groups, each receiving either the vehicle or Clomiphene citrate (1 mg/kg) or Carvedilol or a combination of Clomiphene citrate and Carvedilol, respectively from days 22–36. Neurobehavioral studies were conducted on day 35 (Elevated plus maze and Y maze) and day 36 (Novel object recognition). The serum levels of the antioxidants Superoxide dismutase, Catalase, Interleukin 1B (IL-1B), and the gene expression of nuclear factor-erythroid factor 2-related factor 2 (Nrf2), Nuclear Factor k-Beta (NFKB), and acetylcholine esterase in the frontal brain homogenate was determined. ResultBoth Carvedilol and the combination therapy reversed the anxiety-like behavior, while Clomiphene citrate and the combination therapy ameliorated the spatial and non-spatial memory impairment observed in PCOS rats. Carvedilol, Clomiphene citrate, and the combination therapy increased the serum concentration of SOD and Catalase and decreased the serum concentration of IL-1B. The combination therapy up-regulated the NRF-2, NFKB, and acetylcholine esterase gene expression. ConclusionStudy showed that the combination of carvedilol and clomiphene citrate has anxiolytic potential and improved cognitive functions in PCOS rats. This might have been achieved by carvedilol and clomiphene citrate's ability to modulate the cholinergic system and the Nrf2 pathway while downregulating the NFκB signaling pathway.

Different cold tolerances among three strains of large yellow croaker: related to antioxidant defense and energy metabolism

The aim of this study was to compare low-temperature tolerances in different strains of large yellow croaker. Dai Qu (DQ), Min-Yue Dong (MY), and Quan Zhou (NZ) strains of large yellow croaker were subjected to cold stress (8.6°C) for 12h, 24h, 48h, and 96h. Survival rate, histological observation, and antioxidant and energy metabolism indicators were determined. The results showed that compared with the DQ group and MY group, NZ group aggravated hepatic structure, enhanced ROS, lactate, and anaerobic metabolism (PK gene expression and activity), while inhibited ATP, GSH, antioxidant enzymes (mRNA levels and activities of SOD, GPx, and CAT), and aerobic metabolism enzymes (mRNA levels and activities of F-ATPase, SDH, and MDH), indicating the reduction of cold tolerance in the NZ group was closely correlated with the decrement of antioxidative capacity and energy metabolism efficiency. Nrf2 and AMPK gene expressions were correlated with antioxidant and energy metabolism mRNA levels, respectively, suggesting Nrf2 and AMPK might participate in the modulation of target genes during the cold-stress adaptation. In conclusion, low temperature tolerance of fish depended on the antioxidant defense and energy metabolism efficiency, which contributes to understanding the underlying mechanisms of cold adaptation in large yellow croaker.

The neuroprotective effect of ascorbic acid against imidacloprid-induced neurotoxicity and the role of HO-1 in mice.

Imidacloprid (IMI) is not only a neurotoxic agricultural pesticide but also a possible food contaminant. The aims of this study were to (1) explore the relationship between recurrent IMI administration and neuronal toxicity in mice and (2) evaluate the potential neuroprotective effect of ascorbic acid (AA), a substance with significant free radical scavenger and having property to block the inflammatory pathways. Mice were categorized as naïve controls (administered vehicles for 28 days); the IMI-treatment animal group (administered po 45-mg/kg body weight of IMI per day for 28 days); and the IMI + AA treatment animal group (administered the same IMI dose + 200 mg/kg of AA orally for 28 days). On day 28, memory losses were assessed using the Y-maze and novel target identification behavioral tests. Mice were sacrificed 24 h after the final IMI treatments, as well as hippocampus tissues, were utilized to determine histological assessments, oxidative stress biomarkers, and Heme oxygenase-1 (HO-1) and nuclear factor erythroid 2-related factor 2 (Nrf2) gene expression levels. The findings demonstrated that IMI-treated mice had substantial impairment of spatial and non-spatial memory functions, as well as reduced antioxidant enzyme and acetylcholinesterase activity. The AA neuroprotective action was achieved through the suppression of the HO-1 expression as well as the stimulation of Nrf2 expression in hippocampal tissues. In summary, recurrent IMI exposure causes oxidative stress and neurotoxicity in mice, and the administration of AA significantly reduces the IMI toxicity possibly by the activation of the HO-1/Nrf2 pathway.

Prognostic value of Nrf2/HO-1 expression and its correlation with occurrence in esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is thought to be started and developed by genes associated with inflammation. A cancer's ability to spread and grow can be aided by nuclear factor erythroid-2 related factor 2 (Nrf2) hyperactivation, which can also make a tumor more resistant to chemotherapy and radiation treatment. However, it is still unknown how Nrf2 gene expression affects ESCC prognosis and controls function throughout ESCC advancement. The expression of Nrf2 and HO-1 in ESCC and precancerous esophageal precancerous lesions was analyzed, and their relationship with esophageal squamous cell carcinoma was analyzed. Immunohistochemistry (IHC) was used to confirm the expression of Nrf2 and heme oxygenase-1 (HO-1) proteins in tissue microarrays from Chinese populations with ESCC. We looked at the connections between Nrf2/HO-1 expression and invading immune cells using the TIMER database. Ethnicity and N stage are associated with Nrf2 overexpression. Differentiation, N stage, vascular invasion, distant metastasis, and American Joint Committee on Cancer (AJCC) staging are all associated with HO-1 overexpression. The expression of Nrf2 and HO-1 had a favorable correlation. Patients with elevated Nrf2 and HO-1 expression had lower progression-free survival (PFS) and overall survival (OS). In high-grade intraepithelial neoplasia, Nrf2 and HO-1 expression generally occurred, partially in low-grade intraepithelial neoplasia specimens, and rarely in normal mucosa. We further show that Nrf2 suppression is linked to higher immunological marker expression and lower immune cell infiltration. The prognosis of ESCC may be improved by inhibiting the expression of Nrf2 and HO-1. A lack of immune cells was seen in ESCC with Nrf2 impairment.

N-Acetylcysteine Attenuates the Prednisolone-Induced Osteoporosis via Rescuing the Nuclear Factor Erythroid 2-Related Factor 2-Antioxidant Responsive Element Axis Activity in Mice

We aimed to investigate the effect and potentialmechanism of N-acetylcysteine (NAC), as an antioxidant, on prednisolone-induced osteoporosis. C57bl/6 mice were subcutaneously delivered with prednisolone to induce osteoporosis. The bone marrow mesenchymal stem cells (MSCs) from mice were induced to osteoblast differentiation and treated with prednisolone in vitro. Meanwhile, the NAC or Nrf2 activator Oltipraz (OPZ) was supplied in the prednisolone treatment. The osteoporosis was determined by bone mineral density, trabecular bone volume, and the parameters of bone absorption and formation. Additionally, the Nrf2, ARE-driven genes HMOX-1, GCLC, ME1, and NQO1 expression were measured by western blot or qRT-PCR. The reactive oxygen species (ROS) was measured by a commercial kit. Prednisolone significantly deceased the bone volume, osteoblastic bone formation, osteogenesis of MSCs, and the expression of Nrf2 and ARE-driven genes. On the contrary, prednisolone promoted ROS production and osteoclastic bone absorption. However, the supplement of NAC or OPZ with prednisolone treatment could markedly rescue the Nrf2 and ARE-droven genes expression, reduce the ROS, alleviate the bone loss, and protect the osteogenesis of MSCs. Our results demonstrated that NAC presented a protective property of Nrf2-ARE axis and resulting prevention of prednisolone-induced osteoporosis.

Possible Role of Oxidative Stress and Nrf2/HO-1 Pathway in Pentylenetetrazole-induced Epilepsy in Aged Rats.

To examine the impact of aging on the response of rats to pentylenetetrazole (PTZ)-induction of epilepsy and the possible role of oxidative stress and nuclear factor erythroid 2-related factor 2 (Nrf2)/ heme oxygenase (HO)-1 pathway in this response. Forty male albino rats were equally allocated into 4 groups; 1) Young control (YC) group, aged 8-12 weeks, 2) Old control (OC) group, aged 24 months, 3) PTZ-Young group: young rats received PTZ (50 mg/Kg, i.p. every other day) for 2 weeks and 4) PTZ-Old group: as group 3 but rats were old. The seizure score stage and latency to the first jerk were recorded in rats. Redox state markers in brain tissues including malondialdehyde (MDA), catalase and total antioxidant capacity (TAC) were evaluated. Also, the expression of Nrf2 and HO-1 genes were measured in the brain tissues. Old rats showed an early and a significant rise in the seizure score with PTZ administration and a significant drop in the seizure latency compared to young rats (P <0.01). Also, old rats showed a significantly higher MDA concentration and a significantly lower TAC and catalase activity than young rats (P <0.01). Moreover, the expression of Nrf2 and HO-1 was significantly lowered in old rats compared to young rats with PTZ administration (P < 0.01). Aging increases the vulnerability of rats to PTZ-induced epilepsy. An effect might come down to the up-regulation of oxidative stress and the down regulation of antioxidant pathways including Nrf2 and HO-1.

Propolis consumption by asymptomatic HIV-individuals: Better redox state? A prospective, randomized, double-blind, placebo-controlled trial

Propolis is a natural product has many biological properties of clinical interest, such as anti-inflammatory and antioxidant. Considering that people living with HIV/aids (PLWHA) on effective combined antiretroviral therapy (cART) present early aging due to an intense immune activation, inflammation, and redox imbalance, propolis consumption could offer a benefit to such patients. This double-blind longitudinal study evaluated whether Brazilian green propolis pills intake (500 mg/day for three months) would decrease the oxidative stress of virological suppressed HIV-individuals. To compare each group (propolis, n = 20 versus placebo, n = 20) in both moments (M0, before and M1, after the intervention), the following markers were assessed: plasma malondialdehyde (MDA), carbonylation, total oxide nitric, total antioxidant capacity (TAP), superoxide dismutase, catalase, and NFkB and NRF2 gene expression. Data were analyzed using Poisson, Gamma distribution and ANOVA followed by Tukey-Kramer. The groups were homogeneous regarding age, gender, time of diagnosis/ treatment, cART scheme, CD4+ T cell count, and no changes were observed in the diet food, or patients’ lifestyles. A decreased MDA concentration was seen in the propolis group (M0 = 0.24 ± 0.13, M1 = 0.20 ± 0.10 protein nmol/mg; p = 0.005) as well as a slight but non-significant increase of TAP (M0 = 49.07 ± 13.26, M1 = 52.27 ± 14.86%; p = 0.06). One may conclude that propolis promoted a lower lipid peroxidation and improved the antioxidant system, suggesting that its use may be beneficial to PLWHA in an attempt to contain the intense inflammatory and oxidant activity.

Polystyrene microplastic particles induced hepatotoxic injury via pyroptosis, oxidative stress, and fibrotic changes in adult male albino rats; the therapeutic role of silymarin

Microplastics (MPs) have become a worldwide issue because of their persistence in marine organisms, their accumulation in the food chains, and their inevitable human exposure. Silymarin is a therapeutic agent used in the treatment of multiple liver diseases. The study aimed to explore the potential therapeutic effect of 2 weeks of silymarin treatment against the effects of two sizes of 1 and 5 μm of polystyrene microplastic particles (PS-MPs) on the liver after 6 weeks of the study period. Animals were divided into negative and positive control, silymarin group (200 mg/kg), PS-MP groups of 1 and 5 μm size (0.02 mg/kg), 1 μm size PS-MPs + silymarin group, and 5 μm size PS-MPs + silymarin group, animals were treated once daily by oral gavage. The study revealed that hepatotoxicity induced by two diameters of PS-MPs with marked destructive effects of 1 μm size greater than that of 5 μm size and the effective therapeutic role of silymarin in improving PS-MPs caused hepatotoxic injury, particularly with 5 μm PS-MPs size; through regression of liver pathology (hepatic cell lysis, inflammation, fibrotic changes, and collagen deposition), restoring ultrastructure morphology (mitochondrial destruction and accumulation of lipid droplets accumulation). It improved liver function by reducing serum AST, ALT, LDH, total cholesterol, and triglycerides. It also reduced oxidative stress by reducing serum MDA, increasing TAC, down-regulation of iNOS, and up-regulation of Nrf2 and HO-1 hepatic gene expression. Furthermore, it relieved pyroptosis by negatively regulating the expression of the NLRP3, caspase-1, and IL-1β hepatic gene expression. The results suggested silymarin’s therapeutic effects in treating PS-MPs-induced hepatotoxic injury and recommended its use as a postexposure treatment for a longer duration.

Sex-specific association of exposure to air pollutants and Nrf2 gene expression and inflammatory biomarkers in exhaled breath of healthy adolescents

Studies investigating the nuclear factor erythroid 2-related factor 2 (Nrf2) expression levels in the respiratory system of healthy subjects are scarce. Moreover, separate studies on the health-related outcomes of air pollution for each sex are limited. The current panel study investigated sex-specific Nrf2 expression levels and related oxidative stress and inflammatory responses among healthy adolescents exposed to PM2.5, PM10, O3, and PM2.5-bounded metals in a high traffic region. Forty-nine healthy nonsmoking subjects participated in the study for five consecutive months (Nov. 2019 to Feb. 2020). Each subject was asked to provide 1 mL of exhaled breath condensate (EBC). Data were analyzed using linear mixed-effects models. The results showed that PM10, PM2.5, O3, and PM2.5-bounded metals were negatively linked to Nrf2 expression level in EBC of females with −58.3% (95% CI: 79.5, −15.4), −32.1% (95% CI: −50.3, −7.1), −76.2% (95% CI: −92.6, −23.9), and −1.9 (95% CI: −3.4, −0.4), respectively. While our results presented no significant association between the studied pollutants and Nrf2 gene expression in males, significant associations were observed between the pollutants and total nitric oxide (NOx), interleukins 6 (IL-6), and tumor necrosis factor-alpha (TNF-α) in the EBC of females. In the case of males, only EBC cytokines showed a significant association with air pollutants. Overall, this study suggests that exposure to ambient air pollutants may affect the respiratory system with biologically different mechanisms in males and females. PM2.5 concentration had a positive correlation with exhaled TNF-α and IL6 values in females while positive correlation with TNF-α and negative correlation with IL6 values in males. O3 had a negative correlation with TNF-α in males.

Impact of protocatechuic acid on alleviation of pulmonary damage induced by cyclophosphamide targeting peroxisome proliferator activator receptor, silent information regulator type-1, and fork head box protein in rats

Cyclophosphamide (CP) is a chemotherapeutic agent that causes pulmonary damage by generating free radicals and pro-inflammatory cytokines. Pulmonary damage has a high mortality rate due to the severe inflammation and edema occurred in lung. PPARγ/Sirt 1 signaling has been shown to be cytoprotective effect against cellular inflammatory stress and oxidative injury. Protocatechuic acid (PCA) is a potent Sirt1 activator and exhibits antioxidant as well as anti-inflammatory properties. The current study aims to investigate the therapeutic impacts of PCA against CP-induced pulmonary damage in rats. Rats were assigned randomly into 4 experimental groups. The control group was injected with a single i.p injection of saline. CP group was injected with a single i.p injection of CP (200 mg/kg). PCA groups were administered orally with PCA (50 and 100 mg/kg; p.o.) once daily for 10 consecutive days after CP injection. PCA treatment resulted in a significant decrease in the protein levels of MDA, a marker of lipid peroxidation, NO and MPO along with a significant increase in GSH and catalase protein levels. Moreover, PCA downregulated anti-inflammatory markers as IL-17, NF-κB, IKBKB, COX-2, TNF-α, and PKC and upregulated cytoprotective defenses as PPARγ, and SIRT1. In addition, PCA administration ameliorated FoxO-1 elevation, increased Nrf2 gene expression, and reduced air alveoli emphysema, bronchiolar epithelium hyperplasia and inflammatory cell infiltration induced by CP. PCA might represent a promising adjuvant to prevent pulmonary damage in patients receiving CP due to its antioxidant and anti-inflammatory effects with cytoprotective defenses.

Protective effects of baicalin against L-glutamate-induced oxidative damage in HT-22 cells by inhibiting NLRP3 inflammasome activation via Nrf2/HO-1 signaling.

To explore the ability and underlying molecular mechanisms involved in the protective effects of Baicalin (BA) against L-Glutamate-induced mouse hippocampal neuron cell line HT-22. The cell injury model of HT-22 cells was induced by L-glutamate, and cell viability and damage were detected by CCK-8 and LDH assays. Generation of intracellular reactive oxygen species (ROS) was measured by DCFH-DA in situ fluorescence method. The SOD activity and MDA concentration in the supernatants were determined by WST-8 and colorimetric method, respectively. Furthermore, Western blot and real-time qPCR analysis were utilized to detect the expression levels of the Nrf2/HO-1 signaling pathway and NLRP3 inflammasome proteins and genes. L-Glutamate exposure induced cell injuries in HT-22 cells, and the concentration of 5 mM L-Glutamate was chosen to be the modeling condition. Co-treatment with BA significantly promoted cell viability and reduced LDH release in a dose-dependent manner. In addition, BA attenuated the L-Glutamate-induced injuries by decreasing the ROS production and MDA concentration, while increasing the SOD activity. Moreover, we also found that BA treatment up-regulated the gene and protein expression of Nrf2 and HO-1, and then inhibited the expression of NLRP3. Our study found that BA could relieve oxidative stress damage of HT-22 cells induced by L-Glutamate, and the mechanism might be related to the activation of Nrf2/HO-1 and inhibition of NLRP3 inflammasome.

NRF2 signaling pathway: A comprehensive prognostic and gene expression profile analysis in breast cancer.

Breast cancer is the most frequently diagnosed malignant tumor in women and a major public health concern. NRF2 axis is a cellular protector signaling pathway protecting both normal and cancer cells from oxidative damage. NRF2 is a transcription factor that binds to the gene promoters containing antioxidant response element-like sequences. In this report, differential expression of NRF2 signaling pathway elements, as well as the correlation of NRF2 pathway mRNAs with various clinicopathologic characteristics, including molecular subtypes, tumor grade, tumor stage, and methylation status, has been investigated in breast cancer using METABRIC and TCGA datasets. In the current report, our findings revealed the deregulation of several NRF2 signaling elements in breast cancer patients. Moreover, there were negative correlations between the methylation of NRF2 genes and mRNA expression. The expression of NRF2 genes significantly varied between different breast cancer subtypes. In conclusion, substantial deregulation of NRF2 signaling components suggests an important role of these genes in breast cancer. Because of the clear associations between mRNA expression and methylation status, DNA methylation could be one of the mechanisms that regulate the NRF2 pathway in breast cancer. Differential expression of Hippo genes among various breast cancer molecular subtypes suggests that NRF2 signaling may function differently in different subtypes of breast cancer. Our data also highlights an interesting link between NRF2 components' transcription and tumor grade/stage in breast cancer.