Environmental arsenic pollution induced liver oxidative stress injury by regulating miR-155 through inhibition of AUF1.

Arsenic (As), a common environmental pollutant, has become a hot topic in recent years due to its potentially harmful effects. Liver damage being a central clinical feature of chronic arsenic poisoning. However, the underlying mechanisms remain unclear. We demonstrated that arsenic can lead to oxidative stress in the liver and result in structural and functional liver damage, significantly correlated with the expression of AUF1, Dicer1, and miR-155 in the liver. Interestingly, knockdown AUF1 promoted the up-regulatory effects of arsenic on Dicer1 and miR-155 and the inhibitory effects on SOD1, which exacerbated oxidative damage in rat liver. However, overexpression of AUF1 reversed the up-regulatory effects of arsenic on Dicer1 and miR-155, restored arsenic-induced SOD1 depletion, and attenuated liver oxidative stress injury. Further, we verified the mechanism and targets of miR-155 in regulating SOD1 by knockdown/overexpression of miR-155 and nonsense mutant SOD1 3'UTR experiments. In conclusion, these results powerfully demonstrate that arsenic inhibits AUF1 protein expression, which in turn reduces the inhibitory effect on Dicer1 expression, which promotes miR-155 to act on the SOD1 3'UTR region after high expression, thus inhibiting SOD1 protein expression and enzyme activity, and inducing liver injury. This finding provides a new perspective for the mechanism research and targeted prevention of arsenic poisoning, as well as scientific evidence for formulating strategies to prevent and control environmental arsenic pollution.

Distinct concentration-dependent oxidative stress profiles by cadmium in a rat kidney proximal tubule cell line.

Levels and chemical species of reactive oxygen/nitrogen species (ROS/RNS) determine oxidative eustress and distress. Abundance of uptake pathways and high oxygen consumption for ATP-dependent transport makes the renal proximal tubule particularly susceptible to cadmium (Cd2+)-induced oxidative stress by targeting ROS/RNS generation or antioxidant defence mechanisms, such as superoxide dismutase (SOD) or H2O2-metabolizing catalase (CAT). Though ROS/RNS are well-evidenced, the role of distinct ROS profiles in Cd2+ concentration-dependent toxicity is not clear. In renal cells, Cd2+ (10-50 µM) oxidized dihydrorhodamine 123, reaching a maximum at 2-3 h. Increases (up to fourfold) in lipid peroxidation by TBARS assay and H2O2 by Amplex Red were evident within 30 min. ROS and loss in cell viability by MTT assay with 50 µM Cd2+ could not be fully reversed by SOD mimetics Tempol and MnTBAP nor by SOD1 overexpression, whereas CAT expression and α-tocopherol were effective. SOD and CAT activities were attenuated below controls only with >6 h 50 µM Cd2+, yet augmented by up to 1.5- and 1.2-fold, respectively, by 10 µM Cd2+. Moreover, 10 µM, but not 25-50 µM Cd2+, caused 1.7-fold increase in superoxide anion (O2•-), detected by dihydroethidium, paralled by loss in cell viability, that was abolished by Tempol, MnTBAP, α-tocopherol and SOD1 or CAT overexpression. H2O2-generating NADPH oxidase 4 (NOX4) was attenuated by ~50% with 10 µM Cd2+ at 3 h compared to upregulation by 50 µM Cd2+ (~1.4-fold, 30 min), which was sustained for 24 h. In summary, O2•- predominates with low-moderate Cd2+, driving an adaptive response, whereas oxidative stress by elevated H2O2 at high Cd2+ triggers cell death signaling pathways.Highlights Different levels of reactive oxygen species are generated, depending on cadmium concentration. Superoxide anion predominates and H2O2 is suppressed with low cadmium representing oxidative eustress. High cadmium fosters H2O2 by inhibiting catalase and increasing NOX4 leading to oxidative distress. Superoxide dismutase mimetics and overexpression were less effective with high versus low cadmium. Oxidative stress profile could dictate downstream signalling pathways.

OPTN gene therapy increases autophagy and protects mitochondria in SOD1-G93A-expressing transgenic mice and cells.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder characterized by progressive motor neuron (MN) death. Mutation of the superoxide dismutase 1 (SOD1) gene, which results in abnormal protein aggregation, is one of the causes of familial ALS. Autophagic dysfunction occurs in SOD1-G93A mutant mice as the disease progresses, but the etiology of this disease is still unclear. Optineurin (OPTN) is an adaptor that is involved in autophagy and participates in aggrephagy and mitophagy. Previous studies have established that OPTN mutations contribute to diseases such as glaucoma and ALS. However, the function of OPTN in autophagy and mitophagy has not been intensively investigated in models of ALS. In this study, we assessed the beneficial effect of OPTN on autophagy and mitochondrial function by intrathecally injecting adeno-associated virus 9 (AAV9)-OPTN into SOD1-G93A transgenic mice and by administering lentivirus (LV)-OPTN to cells expressing the SOD1-G93A mutant protein. The expression of voltage-dependent anion channel 1 (VDAC1) was increased and autophagy was elevated after OPTN gene therapy, as shown by a lower level of p62 and a higher level of microtubule-associated protein 1A/1B-light chain 3 (LC3)-II. Moreover, using electron microscopy, we observed a hyperpolarized mitochondrial transmembrane potential and reversal of mitochondrial morphological abnormalities. Furthermore, the protein level of TANK-binding kinase 1 (TBK1) was increased, suggesting that mitophagy was increased. Our findings from both animal and cell line studies strongly suggest that OPTN gene therapy is a powerful strategy to increase autophagy and protect mitochondria to prevent the progression of ALS and could be effective in the treatment of ALS.

Elevated peripheral levels of receptor-interacting protein kinase 1 (RIPK1) and IL-8 as biomarkers of human amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a devastating fatal neurodegenerative disease with no cure. Receptor-interacting protein kinase 1 (RIPK1) has been proposed to mediate pathogenesis of ALS. Primidone has been identified as an old drug that can also inhibit RIPK1 kinase. We conducted a drug-repurposing biomarker study of primidone as a RIPK1 inhibitor using SOD1G93A mice and ALS patients. SOD1G93A mice treated with primidone showed significant delay of symptomatic onset and improved motor performance. One-hundred-sixty-two ALS participants dosed daily with primidone (62.5 mg) completed 24-week follow-up. A significant reduction was showed in serum levels of RIPK1 and IL-8, which were significantly higher in ALS patients than that of healthy controls (P < 0.0001). Serum RIPK1 levels were correlated positively with the severity of bulbar symptoms (P < 0.05). Our study suggests that serum levels of RIPK1 and IL-8 in peripheral can be used as clinical biomarkers for the activation of RIPK1 in central nervous system in human ALS patients. Repurposing primidone may provide a promising therapeutic strategy for ALS. The effect of primidone for the treatment of other inflammatory diseases may also be considered, since the activation of RIPK1 has been implicated in mediating a variety of inflammatory diseases including COVID-19-associated cytokine release syndrome (CRS). (ChiCTR2200060149).

Neuroprotective effect of the PACAP-ADNP axis on SOD1G93A mutant motor neuron death induced by trophic factors deprivation.

Amyotrophic lateral Sclerosis (ALS) is a neurodegenerative disease characterized by progressive degeneration of motor neurons in the central nervous system. Mutations in the gene encoding Cu/Zn superoxide dismutase (SOD1) account for approximately in 20% of familial ALS cases. The pathological mechanisms underlying the toxicity induced by mutated SOD1 are still unknown. However, it has been hypothesized that oxidative stress (OS) has a crucial role in motor neuron degeneration in ALS patients. Moreover, it has been described that SOD1 mutation interferes expression of nuclear factor erythroid 2-related factor 2 (Nrf2), a protective key modulator against OS and reactive oxygen species (ROS) formation. The protective effect of pituitary adenylate cyclase-activating peptide (PACAP) has been demonstrated in various neurological disorders, including ALS. Some of its effects are mediated by the stimulation of an intracellular factor known as activity-dependent protein (ADNP). The role of PACAP-ADNP axis on mutated SOD1 motor neuron degeneration has not been explored, yet. The present study aimed to investigate whether PACAP prevented apoptotic cell death induced by growth factor deprivation through ADNP activation and whether the peptidergic axis can counteract the OS insult. By using an in vitro model of ALS, we demonstrated that PACAP by binding to PAC1 receptor (PAC1R) prevented motor neuron death induced by serum deprivation through induction of the ADNP expression via PKC stimulation. Furthermore, we have also demonstrated that the PACAP/ADNP axis counteracted ROS formation by inducing translocation of the Nfr2 from the cytoplasm to the nucleus. In conclusion, our study provides new insights regarding the protective role of PACAP-ADNP in ALS.

Effects of infliximab on oxidative stress and inflammation of H9c2 cells induced by H2O2.

This study investigated the effects of infliximab (INF) on oxidative stress and inflammation in H9c2 cardiomyocytes, aiming to address the damage caused by myocardial infarction (MI). H9c2 cells were divided into three groups: control, H2O2 treatment, and H2O2+INF. Cell viability was assessed using the Cell Counting Kit-8 (CCK-8) assay. Protein expression of SOD1, SOD2, TNF-α, and IL-1ß was examined through Western blot, while mRNA expression was analyzed via polymerase chain reaction (PCR). Reactive oxygen species (ROS) levels were measured, and IL-1ß immunofluorescence was utilized to observe inflammation. The expression of IκB-α and IκKα was evaluated to investigate the mechanism of action. INF significantly improved H9c2 cell viability and reduced LDH and MDA levels in the supernatant. Moreover, INF enhanced the expression of SOD1 and SOD2, reducing ROS production. In comparison to the H2O2 group, TNF-α and IL-1ß expression markedly decreased in the H2O2+INF group. Additionally, the fluorescence intensity of IL-1ß immunofluorescence was higher in the H2O2+INF group. INF treatment decreased TNF-α and IL-1ß expression and reduced IL-1ß fluorescence intensity. Furthermore, INF increased IκB-α expression and decreased IκKα expression, suggesting inhibition of the nuclear factor-κB (NF-κB) pathway. In summary, INF effectively suppressed H2O2-induced oxidative stress and inflammation in H9c2 cells by targeting the NF-κB pathway.

Zinc attenuates sulfamethoxazole-induced lipotoxicity by reversing sulfamethoxazole-induced mitochondrial dysfunction and lysosome impairment in a freshwater teleost.

Sulfamethoxazole (SMZ) and zinc (Zn) are widespread harmful materials in aquatic ecosystems and cause toxic effects to aquatic animals under their individual exposure. Although they often co-exist in aquatic environments, little is known about their joint effects and mechanism influencing aquatic animals. Herein, SMZ induced mitochondrial and lysosomal dysfunction, inhibited autophagy flux, and induced lipotoxicity. However, SMZ-induced changes of these physiological and metabolic processes above were reversed by Zn exposure, indicating the antagonism between Zn and SMZ. SOD1-knockdown abrogated the reversing effects of Zn on mitochondria dysfunction and autophagy flux blockage induced by SMZ, suggesting that SOD1 was essential for Zn to reverse SMZ-induced mitochondria dysfunction and autophagy impairment. Our further investigation found that Zn regulated STAT3 translocation to lysosomes and mitochondria to attenuate SMZ-induced lipotoxicity, and SOD1 was required for these processes. Mechanistically, STAT3 was associated with ATP6V1 A in a coiled-coil domain-dependent manner, and pS710-STAT3-and pY753-STAT3-independent manners. Moreover, SMZ suppressed autophagic degradation of damaged mitochondria via inhibiting interaction between STAT3 and ATP6V1 A and increasing pS710-STAT3 level; SMZ impaired mitochondrial ß-oxidation via decreasing pY753-STAT3 level and STAT3 mitochondrial localization. Zn reversed these SMZ-induced effects to alleviate SMZ-induced lipotoxicity. Taken together, our data showed that SMZ impaired mitochondrial ß-oxidation and lysosomal acidification via the downregulation of SOD1, leading to lipotoxicity, and that Zn reversed SMZ-induced changes of these important biological processes and attenuated SMZ-induced lipotoxicity. Thus, our study identified previously unidentified mechanisms for the antagonistic mechanisms of Zn and SMZ on aquatic animals, which provided novel insights into the environmental risk assessments of the joint exposure between heavy metals and antibiotics in the aquatic organisms.

Successes and Challenges in Taming the Beast: Cytotoxic Immune Effectors in Amyotrophic Lateral Sclerosis.

Amyotrophic lateral sclerosis (ALS) is a neurological disease characterized by the progressive loss of motor neurons in the brain and spinal cord. No effective therapeutic strategies have been established thus far, and therefore there is a significant unmet need for effective therapeutics to arrest the disease and reverse the pathologies induced by it. Although the cause of ALS is not well-defined, it appears to be heterogenous. Currently over 20 genes have been found to be associated with ALS. Family history can only be found in 10% of ALS patients, but in the remaining 90% no association with family history is found. The most common genetic causes are expansion in the C9orf72 gene and mutations in superoxide dismutase 1, TDP-43, and FUS. In our recent study, we also found mutations in TDP43 and FUS in ALS patients. To understand the pathogenesis of the disease, we set ourselves the task of analyzing the phenotype and function of all key immune effectors in ALS patients, comparing them with either a genetically healthy twin or healthy individuals. Our study demonstrated a significant increase in functional activation of NK and CD8+ T cytotoxic immune effectors and release of significant IFN-γ not only by the effector cells but also in the serum of ALS patients. Longitudinal analysis of CD8+ T cell-mediated IFN-γ secretion from ALS patients demonstrated continued and sustained increase in IFN-γ secretion with periods of decrease which coincided with certain treatments; however, the effects were largely short-lived. N-acetyl cysteine (NAC), one of the treatments used, is known to block cell death; however, even though such treatment was able to block most of the proinflammatory cytokines, chemokines, and growth factor release, it was not able to block IFN-γ and TNF-α, the two cytokines we had demonstrated previously to induce differentiation of the cells. In this review, we discuss the contribution of cytotoxic effector cells, especially primary NK cells, supercharged NK cells (sNK), and the contribution of sNK cells in expansion and functional activation of CD8+ T cells to memory/effector T cells in the pathogenesis of ALS. Potential new targeted therapeutic strategies are also discussed.

[Cypermethrin induced liver oxidative DNA damage via the JNK/c-Jun pathway].

OBJECTIVE: To clarify the adverse effect of cypermethrin(CYP) on the liver and explore the underlying role of the MAPK pathway. METHODS: Twenty-four Sprague-Dawley(SD) rats were exposed to 0, 5, 10 and 20 mg/(kg·d) ß-CYP by gavage for 31 days. Histomorphological and ultrastructural changes were evaluated by the hematoxylin & eosin(HE) staining and transmission electron microscope(TEM). Levels of MDA and 8-OHdG were detected by ELISA. Expressions of p-JNK and γ-H2A. X were assessed by IHC and IF respectively. RT-PCR was performed to examine mRNA levels of GPx1, GPx4, SOD1, and SOD2 in rat testes. Western blot was conducted to determine protein expressions of GPx1, SOD2, CAT, γ-H2A. X, and the MAPK pathway-associated proteins in rat testes. RESULTS: After ß-CYP exposure, the histomorphology and ultrastructures of rat livers were abnormally altered, as evidenced by hepatic sinusoidal dilation, hepatic plate space formation, mitochondrial crest fracture, etc. Moreover, ß-CYP induced mRNA levels of GPx1, GPx4, SOD1 and SOD2, as well as protein expressions of GPx1 and SOD2 in the liver. Compared to the control, GPx1 and SOD2 protein expressions were decreased by 57.9% and 50.0%(P<0.05), whereas the MDA level was increased by 56.2%(P<0.05) in the high-dose group. Additionally, the JNK/c-Jun pathway, one of MAPK pathways, in the liver was activated by ß-CYP, as shown by the increase of JNK and c-Jun phosphorylation, and protein expressions of p-JNK and p-c-Jun in the high-dose group were elevated by 47.7% and 46.5%(P<0.05) in comparison to the control, but the ERK and p38 pathways were not affected after ß-CYP exposure. Furthermore, ß-CYP promoted 8-OHdG and γ-H2A. X expressions in the liver. Compared to the control, γ-H2A. X protein expression in the mid-and high-dose group was upregulated by 16.9% and 33.9%(P<0.05), respectively. CONCLUSION: Cypermethrin had detrimental effects on the liver. CYP not only directly altered liver histomorphology and ultrastructures, but also caused oxidative stress, which activated the JNK/c-Jun pathway, finally inducing the DNA damage.

Empagliflozin improves kidney senescence induced by D-galactose by reducing sirt1-mediated oxidative stress.

Sodium-glucose cotransporter-2 (SGLT-2) inhibitors have received widespread attention because of their significant protective effects on the kidney. Previous studies have shown that Sirt1, as which is an antiaging protein, is closely related to the maintenance of redox homeostasis. The goal of this study was to determine whether empagliflozin could ameliorate D-galactose-induced renal senescence in mice, and examine the possible mechanisms of Sirt1. We constructed a rapid ageing model in mice by administering D-galactose. An ageing model was constructed by treating cells with high glucose. Treadmill and Y-maze tests were used to assess exercise tolerance and learning memory ability. Pathologically stained sections were used to assess kidney injury. Tissue and cell senescence were evaluated by senescence-associated ß-galactosidase staining. The expression levels of P16, SOD1, SOD2 and Sirt1 were detected by immunoblotting. D-gal-treated mice exhibited significant age-related changes, as measured by behavioural tests and ageing marker protein levels. empagliflozin alleviated these ageing manifestations. In addition, Sirt1, SOD1 and SOD2 levels were downregulated in model mice and upregulated by empagliflozin treatment. Empagliflozin had similar protective effects at the cellular level, and these effects were reduced by the Sirt1 inhibitor. Empagliflozin has an antiaging effect, which may be related to reducing Sirt1-mediated oxidative stress.

Peptides obtained by enzymatic decomposition of mackerel induce recovery from physical fatigue by enhancing the SIRT1-mediated antioxidant effect in the soleus muscle of mice.

Fatigue is a serious health problem, and long-term fatigue can lead to mental illnesses and accelerated aging. Oxidative stress, which causes excessive production of reactive oxygen species, is generally thought to increase during exercise and is an indicator of fatigue. Peptides obtained by enzymatic decomposition of mackerel (EMP) contain selenoneine, a strong antioxidant. Although antioxidants increase endurance, the effects of EMP on physical fatigue are unknown. The present study aimed to clarify this aspect. We investigated the effects of EMP on changes in locomotor activity, expression levels of silent mating type information regulation 2 homolog peroxisome 1 (SIRT1), proliferator-activated receptor-γ coactivator-1α (PGC1α), and antioxidative-related proteins including superoxide dismutase 1 (SOD1), SOD2, glutathione peroxidase 1, and catalase in the soleus muscle following EMP treatment before and/or after forced walking. Treatment with EMP before and after forced walking, and not only at one or another time point, improved the subsequent decrease in the locomotor activity and enhanced the levels of SIRT1, PGC1α, SOD1, and catalase expression in the soleus muscle of mice. Moreover, EX-527, a SIRT1 inhibitor, abolished these effects of EMP. Thus, we suggest that EMP combats fatigue by modulating the SIRT1/PGC1α/SOD1-catalase pathway.

The Effect of Vitamin C and N-Acetylcysteine on Tendon-to-Bone Healing in a Rodent Model of Rotator Cuff Repair.

BACKGROUND: Oxidative stress inhibits tendon-to-bone healing after rotator cuff repair. Regulation of oxidative stress has the potential to accelerate this healing, but its mechanism remains unclear. PURPOSE: To investigate the effects of reducing oxidative stress by applying antioxidants, such as N-acetylcysteine (NAC) and vitamin C (VC), on rotator cuff repair in a rat rotator cuff repair model. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 48 Sprague Dawley rats underwent bilateral surgery to repair the infraspinatus tendon to its insertion site 1 week after detachment. Rats were assigned to either the NAC group, the VC group, or a control group. Histological evaluation was performed via hematoxylin-eosin or toluidine blue staining, and oxidative stress was assessed via dihydroethidium intensity and protein carbonyl concentration at 3 and 6 weeks. Superoxide dismutase 1 (SOD1), SOD2, SOD3, peroxiredoxin 5, collagen type I (COL1), COL3, matrix metalloproteinase 1 (MMP-1), MMP-3, and MMP-13 expression and SOD activity were determined at 3 and 6 weeks. Biomechanical tests were performed at 6 and 12 weeks. RESULTS: Histological evaluation showed that the number of chondrocytes in the NAC group at 6 weeks and in the VC group at 3 and 6 weeks, the area of fibrocartilage at 6 weeks in the VC group, and collagen fibers at 6 weeks in the NAC and VC groups were significantly increased compared with those in the control group. Dihydroethidium intensity at 3 and 6 weeks and protein carbonyls at 6 weeks in the NAC and VC groups were significantly decreased. SOD1 expression and SOD activity at 3 weeks in the VC group and peroxiredoxin 5 expression at 6 weeks in the NAC group were significantly upregulated compared with that in the control group. COL3 expression was significantly upregulated at 6 weeks in the VC group, and MMP-13 expression was significantly decreased at 6 weeks in the NAC and VC groups. The biomechanical strength showed no significant difference. CONCLUSION: Antioxidant treatment, via NAC or VC administration, reduced oxidative stress in the rotator cuff repair site and accelerated healing. CLINICAL RELEVANCE: These findings provide essential indications to develop clinical strategies for improved healing after rotator cuff surgical repair in patients.

The effects of thymol, oxalic acid (Api-Bioxal) and hops extract (Nose-Go) on viability, the Nosema sp. spore load and the expression of vg and sod-1 genes in infected honey bees.

This study was done to investigate the effects of thymol, fumagillin, oxalic acid (Api-Bioxal) and hops extract (Nose-Go) on Nosema sp. spore load, the expression of vitellogenin (vg) and superoxide-dismutase-1 (sod-1) genes and mortality of bees infected with N. ceranae. Five healthy colonies were assigned as the negative control, and 25 Nosema sp. infected colonies were assigned to five treatment groups including: the positive control: no additive to sirup; fumagillin 26.4 mg/L, thymol 0.1 g/L, Api-Bioxal 0.64 g/L and Nose-Go 5.0 g/L sirup. The reduction in the number of Nosema sp. spores in fumagillin, thymol, Api-Bioxal and Nose-Go compared to the positive control was 54, 25, 30 and 58%, respectively. Nosema sp. infection in all infected groups increased (p < .05) Escherichia coli population compared to the negative control. Nose-Go had a negative effect on lactobacillus population compared to other substances. Nosema sp. infection decreased vg and sod-1 genes expression in all infected groups compared to the negative control. Fumagillin and Nose-Go increased the expression of vg gene, and Nose-Go and thymol increased the expression of sod-1 gene than the positive control. Nose-Go has the potential to treat nosemosis if the necessary lactobacillus population is provided in the gut.

Betaine ameliorates high glucose-induced oxidative stress in granulosa cells.

CONTEXT: In diabetes, abnormalities of granulosa cells (GCs) and steroidogenesis are associated with hyperglycaemia-induced oxidative stress. Betaine has beneficial effect in experimental model of diabetes by reducing oxidative stress, inflammation, and apoptosis. AIMS: In this study we investigate the effects of betaine to prevent oxidative stress in GCs induced by high glucose and improve steroidogenesis. METHODS: Primary GCs, isolated from ovarian follicles of C57BL/6 mice were cultured in 5mM (control) and 30mM (hyperglycaemia) of glucose and in presence of 5mM of betaine for 24h. Then antioxidant enzymes, malondialdehyde, oestradiol and progesterone were measured. In addition, the expression of Nrf2 and NF-κB , antioxidant enzymes (Sod1 , Gpx and Cat ) were analysed by qRT-PCR assay. KEY RESULTS: We observed significant (P <0.001) up-regulation of NF-κB and down-regulation of Nrf2 due to high concentration of glucose. Also significant (P <0.001) down-regulation of related antioxidant genes (Cat , Sod1 and GPx ) and activity reduction of these enzymes as well as significant (P <0.001) elevation of malondialdehyde was observed. In addition, betaine treatment compensated the drastic effect of high glucose induced oxidative stress via down-regulating the expression of NF-κB and up-regulating the expression of Nrf2 , Cat , Sod1 and GPx . It was also shown that betaine in the presence of FSH significantly (P <0.001) restored the oestradiol and progesterone level. CONCLUSION: Betaine compensated the antioxidant stress in mouse GCs under hyperglycaemic condition via regulation of Nrf2/NF-κB at transcription level. IMPLICATIONS: As betaine is a natural product and no side effect has been reported to today, we suggest more research needs to be carried out especially on patients whom suffer from diabetes to find the probability of using betaine as a therapeutic agent.

Ginkgolide B caused the activation of the Akt/eNOS pathway through the antioxidant effect of SOD1 in the diabetic aorta.

Ginkgo biloba extract (GBE) helps lower cardiovascular disease risk. Diabetes mellitus (DM)-induced endothelial dysfunction is a critical and initiating factor in the beginning of diabetic vascular complications. It was reported that GBE causes an endothelial-dependent relaxation. This study was designed to figure out the molecular basis on which GBE protects from endothelial dysfunction in diabetes because the underlying mechanisms are unclear. Studies were performed in a normal control group and streptozotocin/nicotinamide-induced DM group. In aortas, notably diabetic aortas, GBE, and ginkgolide B (GB), a constituent of GBE, produced a dose-dependent relaxation. The relaxation by GB was abolished by prior incubation with L-NNA (an endothelial nitric oxide synthase (NOS) inhibitor), LY294002 (a phosphoinositide 3-kinase (PI3K) inhibitor), and Akt inhibitor, confirming the essential role of PI3K/Akt/eNOS signaling pathway. We also demonstrated that GB induced the phosphorylation of Akt and eNOS in aortas. The superoxide dismutase1 (SOD1) expression level decreased in DM aortas, but GB stimulation increased SOD activity and SOD1 expression in DM aortas. Our novel findings suggest that in DM aortas, endothelial-dependent relaxation induced by GB was mediated by activation of SOD1, resulting in activation of the Akt/eNOS signaling pathway.

Sex-based differences of antioxidant enzyme nanoparticle effects following traumatic brain injury.

Following traumatic brain injury (TBI), reactive oxygen species (ROS) are released in excess, causing oxidative stress, carbonyl stress, and cell death, which induce the additional release of ROS. The limited accumulation and retention of small molecule antioxidants commonly used in clinical trials likely limit the target engagement and therapeutic effect in reducing secondary injury. Small molecule drugs also need to be administered every several hours to maintain bioavailability in the brain. Therefore, there is a need for a burst and sustained release system with high accumulation and retention in the injured brain. Here, we utilized Pro-NP™ with a size of 200 nm, which was designed to have a burst and sustained release of encapsulated antioxidants, Cu/Zn superoxide dismutase (SOD1) and catalase (CAT), to scavenge ROS for >24 h post-injection. Here, we utilized a controlled cortical impact (CCI) mouse model of TBI and found the accumulation of Pro-NP™ in the brain lesion was highest when injected immediately after injury, with a reduction in the accumulation with delayed administration of 1 h or more post-injury. Pro-NP™ treatment with 9000 U/kg SOD1 and 9800 U/kg CAT gave the highest reduction in ROS in both male and female mice. We found that Pro-NP™ treatment was effective in reducing carbonyl stress and necrosis at 1 d post-injury in the contralateral hemisphere in male mice, which showed a similar trend to untreated female mice. Although we found that male and female mice similarly benefit from Pro-NP™ treatment in reducing ROS levels 4 h post-injury, Pro-NP™ treatment did not significantly affect markers of post-traumatic oxidative stress in female CCI mice as compared to male CCI mice. These findings of protection by Pro-NP™ in male mice did not extend to 7 d post-injury, which suggests subsequent treatments with Pro-NP™ may be needed to afford protection into the chronic phase of injury. Overall, these different treatment effects of Pro-NP™ between male and female mice suggest important sex-based differences in response to antioxidant nanoparticle delivery and that there may exist a maximal benefit from local antioxidant activity in injured brain.

Ceria Nanoparticles as Copper Chaperones that Activate SOD1 for Synergistic Antioxidant Therapy to Treat Ischemic Vascular Diseases.

All exogenous nanomaterials undergo rapid biotransformation once injected into the body and fall short of executing the intended purpose. Here, it is reported that copper-deposited ceria nanoparticles (CuCe NPs) exhibit enhanced antioxidant effects over pristine ceria nanoparticles, as the released copper buffers the depletion of glutathione while providing the bioavailable copper as a cofactor for the antioxidant enzyme, superoxide dismutase 1. The upregulated intracellular antioxidants along with the ceria nanoparticles synergistically scavenge reactive oxygen species and promote anti-inflammation and M2 polarization of macrophages by modulating signal transducer and activator of transcription 1 and 6 (STAT1 and STAT6). The therapeutic effect of CuCe NPs is demonstrated in ischemic vascular diseases (i.e., murine models of hindlimb ischemia and myocardial infarction) in which the copper-deposition affords increased perfusion and alleviation in tissue damage. The results provide rationale that metal oxide nanomaterials can be designed in a way to induce the upregulation of specific biological factors for optimal therapeutic performance.

Antioxidant Effects of Rhodoxanthin from Potamogeton crispus L. on H2 O2 -Induced RAW264.7 Macrophages Cells.

Potamogeton crispus L. (P. crispus) is the type of a widely distributed perennial herbs, which is rich in rhodoxanthin. In this research work, five antioxidant indexes in vitro were selected to study the antioxidant activity of rhodoxanthin from P. crispus (RPC). A model of hydrogen peroxide (H2 O2 ) -induced oxidative damage in RAW264.7 cells was established to analyze the antioxidant effect and potential mechanism of RPC. The levels of ROS, MDA and the activities of oxidation related enzymes by H2 O2 were determined by enzyme linked immunosorbent assay (ELISA). The mRNA expression of Nrf-2, HO-1, SOD1 and SOD2 was measured by qRT-PCR assay. According to the results, RPC had free radical scavenging ability for 2, 2-diphenyl-1-trinitrohydrazine (DPPH), 2,2'-azinobis(3-ethylbenzo-thiazoline-6-sulfonic acid radical ion) (ABTS), hydroxyl radical and superoxide anion. RPC significantly decreased the level of MDA and ROS and LDH activity, while increased GSH level and activities of SOD, GSH-Px and CAT. It was showed that RPC could increase the mRNA expression of Nrf-2, HO-1, SOD1 and SOD2 in RAW264.7 cells in a dose-dependently manner. In summary, RPC treatment could effectively attenuate the H2 O2 -induced cell damage rate, and the mechanism is related to the reduction of H2 O2 induced oxidative stress and the activation of Nrf-2 pathway.

Molecular cloning and characterization of Cu-Zn superoxide dismutase (sod1) gene in brown trout and its expression in response to acute aquaculture stressors.

Aquaculture species are often exposed to acute stressors such as low water levels and handling during routine aquaculture procedures. This might result in oxidative stress by the increased reactive oxygen species (ROS)' production (e.g., superoxide anion). The harmful effects of ROS are eliminated by a defense system, referred antioxidant defense system (ADS). sod1 is the first gene involved in the ADS. Therefore, we cloned and characterized the open reading frame of the sod1 in brown trout. Then, we determined the effects of low water level and handling stress on sod1 mRNA expression in the liver and gills at 0 min, 1 and 2 h. The total RNA isolated was used to synthesize cDNA for RT-qPCR analysis. Phylogenetic tree, identity/similarity percentages, genomic organization, and conserved gene synteny analyses were applied to characterize Sod1/sod1. While low water level stress upregulated sod1 expression in the liver compared to the control group, no significant differences were observed in the gills between experimental groups. However, brown trout differently responded to handling stress at different time intervals in both tissues. Transcriptional differences were also noted between the sexes. This study contributes to the current understanding of the molecular mechanism between oxidative stress and ADS.

Empagliflozin Exhibits Hepatoprotective Effects Against Bile Duct Ligation-induced Liver Injury in Rats: A Combined Molecular Docking Approach to In Vivo Studies.

BACKGROUND: Cholestatic liver damage is a chronic disease caused by dysfunction of the hepaticbiliary system. Oxidative stress and inflammation are essential factors in the pathogenesis of cholestasis. Thus, the current study was designed to examine the effect of empagliflozin on bile duct ligation-induced liver damage in rats. METHODS: This study was done on male Wistar rats, which were randomly assigned to the four experimental groups: sham control (SC), bile duct ligation (BDL), SC plus empagliflozin (SC+EMPA) (receiving 10 mg of EMPA orally for 7 days), BDL plus empagliflozin 10 mg/kg (BDL+ EMPA). At the end of the study, the rats were sacrificed, and serum and tissue samples were collected to analyze biochemical parameters, biomarkers of oxidative stress, inflammatory markers, and histopathological changes. The molecular docking technique was performed to elucidate the interaction of EMPA and Cu/Zn-superoxide dismutase (SOD1). RESULTS: The results showed that BDL elevated the serum activity of ALT, AST, ALP, and levels of TBIL and TPro. BDL also intensifies the oxidative stress state in rats, which was confirmed by augmenting lipid peroxidation (MDA), protein oxidation (PCO), and altering antioxidant defense parameters through decreased SOD, catalase (CAT), and glutathione peroxidase (GPX) levels. Furthermore, the histopathological changes in the liver demonstrated the aggravation of inflammation and oxidative stress. In contrast, treatment with EMPA has shown anti-inflammatory and anti-oxidant effects by reducing TNF-α and IL-6 pro-inflammatory marker proteins, restoring the antioxidant status (increased SOD and GPX), reducing ALT, AST, ALP, TBIL levels, and protein oxidation, and improving the histopathological alterations through reducing bile duct proliferation, fibrosis, focal and portal inflammation. According to the attained findings, the SOD1 activity can be regulated by the EMPA. Our documentation presents direct evidence at the molecular level related to the ability of EMPA to exert its antioxidant performance through certain measures in a particular molecular route. CONCLUSION: The results showed EMPA to have hepatic protective effects in rats against cholestatic liver injury, an effect mediated by its antioxidant and anti-inflammatory properties.