Purification, Identification, and Mechanistic Investigation of Novel Selenium-Enriched Antioxidant Peptides from Moringa oleifera Seeds.

In this study, five novel Se-enriched antioxidant peptides (FLSeML, LSeMAAL, LASeMMVL, SeMLLAA, and LSeMAL) were purified and identified from Se-enriched Moringa oleifera (M. oleifera) seed protein hydrolysate. The five peptides showed excellent cellular antioxidant activity, with respective EC50 values of 0.291, 0.383, 0.662, 0.1, and 0.123 µg/mL. The five peptides (0.025 mg/mL) increased the cell viability from 78.72 to 90.71, 89.16, 93.92, 83.68, and 98.29%, respectively, effectively reducing reactive oxygen species accumulation and significantly increasing superoxide dismutase and catalase activities in damaged cells. Molecular docking results revealed that the five novel Se-enriched peptides interacted with the key amino acid of Keap1, thus directly blocking the interaction of Keap1-Nrf2 and activating the antioxidant stress response to enhance the ability of scavenging free radicals in vitro. In conclusion, Se-enriched M. oleifera seed peptides exhibited significant antioxidant activity and can be expected to find widespread use as a highly active natural functional food additive and ingredient.

Astragaloside IV alleviates stroke-triggered early brain injury by modulating neuroinflammation and ferroptosis via the Nrf2/HO-1 signaling pathway

Purpose: Stroke is an acute cerebrovascular disease. Astragaloside IV (AS-IV) is an active ingredient extracted from Astragalus membranaceus with an established therapeutic effect on central nervous system diseases. This study examined the neuroprotective properties and possible mechanisms of AS-IV in stroke-triggered early brain injury (EBI) in a rat transient middle cerebral artery occlusion (MCAO) model. Methods: The neurological scores and brain water content were analyzed. 2,3,5-triphenyl tetrazolium chloride (TTC) staining was utilized to determine the infarct volume, neuroinflammatory cytokine levels, and ferroptosis-related genes and proteins, and neuronal damage and molecular mechanisms were evaluated by terminal deoxynucleotidyl transferase dutp nickend labeling (TUNEL) staining, western blotting, and real-time polymerase chain reaction. Results: AS-IV administration decreased the infarct volume, brain edema, neurological deficits, and inflammatory cytokines TNF-α, interleukin-1ß (IL-1ß), IL-6, and NF-κB, increased the levels of SLC7A11 and glutathione peroxidase 4 (GPX4), decreased lipid reactive oxygen species (ROS) levels, and prevented neuronal ferroptosis. Meanwhile, AS-IV triggered the Nrf2/HO-1 signaling pathway and alleviated ferroptosis due to the induction of stroke. Conclusion: Hence, the findings of this research illustrate that AS-IV administration can improve delayed ischemic neurological deficits and decrease neuronal death by modulating nuroinflammation and ferroptosis via the Nrf2/HO-1 signaling pathway.

Involvement of Hypoxia-Inducible Factor 1-α in Experimental Testicular Ischemia and Reperfusion: Effects of Polydeoxyribonucleotide and Selenium.

Polydeoxyribonucleotide (PDRN) is an agonist of the A2A adenosine receptor derived from salmon trout sperm. Selenium (Se) is a trace element normally present in the diet. We aimed to investigate the long-term role of PDRN and Se, alone or in association, after ischemia-reperfusion (I/R) in rats. The animals underwent 1 h testicular ischemia followed by 30 days of reperfusion or a sham I/R and were treated with PDRN or Se alone or in association for 30 days. I/R significantly increased hypoxia-inducible factor 1-α (HIF-1α) in Leydig cells, malondialdehyde (MDA), phosphorylated extracellular signal-regulated kinases 1/2 (pErk 1/2), and apoptosis decreased testis weight, glutathione (GSH), testosterone, nuclear factor erythroid 2-related factor 2 (Nrf2), induced testicular structural changes, and eliminated HIF-1α spermatozoa positivity. The treatment with either PDRN or Se significantly decreased MDA, apoptosis, and HIF-1α positivity of Leydig cells, increased testis weight, GSH, testosterone, and Nrf2, and improved the structural organization of the testes. PDRN and Se association showed a higher protective effect on all biochemical, structural, and immunohistochemical parameters. Our data suggest that HIF-1α could play important roles in late testis I/R and that this transcriptional factor could be modulated by PDRN and Se association, which, together with surgery, could be considered a tool to improve varicocele-induced damages.

Açaí (Euterpe Oleraceae Mart.) Seeds Regulate NF-κB and Nrf2/ARE Pathways Protecting Lung against Acute and Chronic Inflammation.

BACKGROUND/AIMS: Respiratory diseases are the world's biggest cause of mortality and disability. Specific nutrients have been proposed to positively affect disease progression as novel therapy alternatives to glucocorticosteroids. There has been a lot of attention in the possible health advantages of dietary assumption of Açai Seeds, popular native fruit found in the Amazon region which is rich in bioactive compounds. Until today nobody investigated the beneficial property of Açai Seeds administration in lung disease. METHODS: In our study we use two model of lung disease: for acute lung disease we use an intrapleural injection of Carrageenan; for chronic disease we used an intratracheal instillation of bleomycin. Açai Seeds was administered orally dissolved in saline. RESULTS: We found that Açai Seeds was able to reduce histological alteration, cells infiltration, pro inflammatory cytokine release, inflammation, and oxidative stress in both acute and chronic model of lung disease. CONCLUSION: Our data clearly demonstrate for the first time that Açai Seeds administration was useful against lung disease by the reduction of NF-κB nuclear translocation and by the stimulation of Nrf2/ARE pathways promoting the physiological antioxidant defense.

Biotechnologically-Produced Myconoside and Calceolarioside E Induce Nrf2 Expression in Neutrophils.

The pathological manifestation of various diseases can be suppressed by the activation of nuclear factor erythroid 2 p45-related factor 2 (Nrf2), a transcriptional regulator of the cellular redox balance. Haberlea rhodopensis Friv. is a resurrection plant species endemic for Bulgaria, containing biologically active phenylethanoid glycosides that might possess antioxidant or redox activity. This study aimed to analyze the metabolic profile of in vitro cultured H. rhodopensis and to identify molecules that increase Nrf2 expression in bone marrow neutrophils. Fractions B, D, and E containing myconoside, or myconoside and calceolarioside E in ratios 1:0.6 and 0.25:1 were found to be the most active ones. Fraction B (200 µg/mL) improved neutrophil survival and strongly increased the Nrf2 intracellular level, while D and E, as well as, myconoside and calceolarioside E at the same ratios had a superior effect. Calceolarioside E (32 µg/mL) had stronger activity than myconoside, the effect of which was very similar to that of 2-cyano-3,12-dioxo-oleana-1,9(11)-dien-28-oic acid methyl ester (CDDO-Me), used as a positive control. These data indicate that both molecules, used alone or in combination have stimulatory activity on the endogenous Nrf2 level, indicating their therapeutic potential to regulate the cellular redox homeostasis oxidative stress-associated pathologies.

Protective effects of hyperbaric oxygen preconditioning against LPS-induced acute lung injury in rats.

INTRODUCTION: Acute lung injury (ALI) is generally caused by oxidative damages and pulmonary overinflammations. Hyperbaric oxygen preconditioning (HBO2-PC) has been proven protective against oxidative-stress-related injuries. In this study, we investigated the effect of HBO2-PC on lipopolysaccharide (LPS)-induced ALI in rats. METHODS: Thirty-two Sprague-Dawley rats randomly assigned into Sham, HBO2-PC, ALI and HBO2-PC÷ALI groups (eight in each group) were sacrificed at 12 hours after the injection of LPS. The severity of ALI in rats was assessed in terms of histopathological changes in addition to wet/dry weight ratios. The levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1ß in serum and lung homogenates were measured by enzyme-linked immunosorbent and qRT-PCR assays. Activities by hydrogen peroxide (H2O2), malondialdehyde (MDA), myeloperoxidase (MPO) as well as superoxide dismutase (SOD) in rat lungs were tested for neutrophil infiltration. Meanwhile the oxidative stress molecular markers nuclear factor-kappa B(NF-κB) p65 and nuclear factor erythroid 2-related factor 2 (Nrf2), together with its downstream heme-oxygenase 1 (HO-1) and NAD(P)H: quinone oxidoreductase 1 (NQO1) were also quantified. RESULTS: HBO2-PC significantly alleviated LPS-induced ALI, lowered the lung injury scores, reduced lung water content, and reduced H2O2, MDA levels as well as MPO activity, while simultaneously improving the arterial partial oxygen pressure (PaO2) and SOD activity. Furthermore, HBO2-PC inhibited the nuclear translocation of NF-κB p65 while enhancing the nuclear translocation of Nrf2, thus upregulating HO-1 and NQO1. CONCLUSIONS: Our results suggest that HBO2-PC was potentially protective for LPS-induced ALI lungs in rats, with a presumed mechanism that suppressed NF-κB while activating Nrf2. We propose that HBO2-PC should be considered a potential therapeutic strategy against ALI in rats.

Molecular signalling of a novel curcumin derivative versus Tadalafil in erectile dysfunction.

The efficacy of a novel curcumin derivative (NCD) versus tadalafil in erectile signalling was assessed. Ten control male rats and 50 diabetic male rats were used and divided into the following: diabetic (DM), curcumin (CURC), NCD, tadalafil and NCD combined with tadalafil rat groups. Cavernous tissue gene expression of heme oxygenase-1 (HO-1), Nrf2, NF-B and p38, enzyme activities of heme oxygenase (HO) and nitric oxide synthase (NOS), cGMP and intracavernosal pressure (ICP)/mean arterial pressure (MAP) were assessed. Results showed that 12 weeks after induction of diabetes, erectile dysfunction (ED) was confirmed by the significant decrease in ICP/MAP, a significant decrease in cGMP, NOS, HO enzyme activities, a significant decrease in HO-1 gene and a significant increase in NF-Ò ß, p38 genes. Administration of all therapeutic interventions led to a significant increase in ICP/MAP, cGMP levels, a significant increase in HO-1 and NOS enzymes, a significant increase in HO-1, and Nrf2 gene expression, and a significant decrease in NF-Ò ß, p38 gene expression. NCD or its combination with tadalafil showed significant superiority and more prolonged duration of action. In conclusion, a tendency was observed that CURC and NCD have high efficacy and more prolonged duration of action in enhancing erectile function.

Selenitetriglicerydes affect CYP1A1 and QR activity by involvement of reactive oxygen species and Nrf2 transcription factor.

Selenitetriglycerides are a group of compounds that contain selenium (Se) (IV). In this paper, we present the results of examinations of three structurally-related selenitetriglicerydes that contain various Se concentrations: 2%, 5% and 7% Selol. The present study concentrates on the effect of Selol on phase 1 and 2 enzyme activity and the implications of free radicals and the nuclear erythroid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway in the activity of this compound. The cytotoxic and cytostatic activities of the three kinds of Selol were evaluated; however, the cytotoxic effect was observed only for 7% Selol. Our results show that 2% Selol acts as a monofunctional inducer of phase 2 enzyme activity, and the induction is mediated by the Nrf2 transcription factor. Selol 7% acts in an opposite manner and induces phase 1 with simultaneous inhibition of phase 2 enzyme activity. The differential effect can be associated with the increase in Se content, leading to a change in the structure of the compound.