Strong Antioxidant Effects Research Articles

Selenomethionine against titanium particle-induced osteolysis by regulating the ROS-dependent NLRP3 inflammasome activation via the β-catenin signaling pathway.

Wear debris-induced osteolysis, especially titanium (Ti) particles-induced osteolysis, is the most common cause of arthroplasty failure with no effective therapy. Previous studies have suggested that inflammation and impaired osteogenesis are associated with Ti particles -induced osteolysis. Selenium (Se) is an essential trace element in the human body, which forms selenomethionine (Se-Met) in nature, and selenoproteins has strong anti-inflammatory and antioxidant stress effects. In this study, the effects of Se-Met on Ti particles-induced osteolysis were observed and the potential mechanism was explored. We found that exogenous Se-Met relieved osteolysis induced by Ti particles in two animal models and MC3T3-E1 cells. We found that the addition of Se-Met effectively inhibited Ti particle-induced inflammation by regulating reactive oxygen species-dependent (ROS-dependent) NOD-like receptor protein 3 (NLRP3) inflammasome activation. These therapeutic effects were abrogated in MC3T3-E1 cells that had received a β-catenin antagonist, suggesting that Se-Met alleviates inflammatory osteolysis via the β-catenin signaling pathway. Collectively, these findings indicated that Se-Met may serve as a potential therapeutic agent for treating Ti particle-induced osteolysis.

Honey and its health benefits in our day-to-day life

Since ancient times, honey has been valued for its healing properties as a natural ingredient. Due to the strong antioxidant and anti-inflammatory effects that flavonoids and phenolic acids have, they have a significant impact on human health. Honey has antibacterial properties and anticancer effects against several tumor types by influencing various biochemical pathways involved in cellular proliferation. The decrease in the serum concentrations of glucose, fructosamine, and glycosylated haemoglobin has also been noted as a further antidiabetic activity. Additionally, honey has a protective impact on the brain system, the respiratory system against bacterial infections and asthma, the cardiovascular system, where it primarily inhibits the oxidation of low-density lipoproteins, and the gastrointestinal system. In athletes, honey has been shown to have positive effects. The goal of this review is to compile and update the most recent data on the effects of honey on health and disease.

Sirtuin3 confers protection against acute pulmonary embolism through anti-inflammation, and anti-oxidative stress, and anti-apoptosis properties: participation of the AMP-activated protein kinase/mammalian target of rapamycin pathway.

An increasing number of studies have suggested that oxidative stress and inflammation play momentous roles in acute pulmonary embolism (APE). Honokiol, a bioactive biphenolic phytochemical substance, is known for its strong anti-oxidative and anti-inflammatory effects, and it served as an activator of sirtuin3 (SIRT3) in the present study. The purposes of the study were to explore the effects of honokiol on APE rats and investigate whether the function of honokiol is mediated by SIRT3 activation. In the study, the rats received a right femoral vein injection of dextran gel G-50 particles (12 mg/kg) to establish the APE model and were subsequently administered honokiol and/or a selective SIRT3 inhibitor 3-(1H-1,2,3-triazol-4-yl)pyridine (3-TYP; 5 mg/kg) intraperitoneally. The results showed that SIRT3 activation by honokiol attenuated the loss in lung function, ameliorated the inflammatory response and oxidative damage, and inhibited apoptosis in lung tissues of the rats with APE but that this was reversed by 3-TYP. In addition, we found that the AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway might be activated by honokiol but restrained by 3-TYP. These results indicated that honokiol was capable of suppressing the adverse effects of APE and that this was diminished by SIRT3 suppression, implying that activation of SIRT3 might serve as a therapeutic method for APE.

In Vitro Antibacterial and Phytochemical Screening of Hypericum perforatum Extract as Potential Antimicrobial Agents against Multi-Drug-Resistant (MDR) Strains of Clinical Origin.

The perennial plant Hypericum perforatum is widely distributed around the world. It has been used for many years in conventional medicine to treat a variety of illnesses, including stress, mild to moderate depression, and minor injuries. This study examined the antimicrobial activity of the H. perforatum total extract and its fractions (n-hexane, ethyl acetate, chloroform, and aqueous) against multi-drug-resistant (MDR) isolates that were gathered from clinical samples, including methicillin-resistant Staphylococcus aureus (MRSA), Enterococcus faecalis, Escherichia coli, and Klebsiella pneumonia. Aerial parts of H. perforatum were collected and extracted using various solvents and were tested versus different isolated bacterial species. The inhibition zone of tested extracts was detected using an agar diffusion assay, and MICs were measured. Phytochemical analysis of promising H. perforatum extract was done using LC-ESI-MS/MS. Ultrastructure examination for the most altered bacteria used transmission electron microscopy. Antioxidant assays were done using DPPH and ABTS scavenging capacity methods. Cytotoxicity was reported versus Vero cells. Different extracts of H. perforatum showed promising antibacterial activity against the pathogens. While the subfractions of the total extract were observed to show lesser inhibition zones and higher MIC values than the total extract of H. perforatum against MDR strains, the total extract of H. perforatum demonstrated the most potent antimicrobial action with an inhibition zone range of 17.9-27.9 mm. MDR-K. pneumoniae was discovered to be the most susceptible strain, which is consistent with the antibacterial inhibitory action of H. perforatum whole extract. Additionally, after treatment at the minimum inhibitory concentration (MIC 3.9 μg/ml), the transmission electron microscope showed alterations in the ultrastructure of the K. pneumoniae cells. Methanol extract from H. perforatum has a CC50 value of 976.75 μg/ml. Future inhibitors that target MDR strains may be revealed by these findings. Additionally, the extracts that were put to the test demonstrated strong antioxidant effects as shown by DPPH or ABTS radical-scavenging assays.

괭이밥 열수 추출물의 항산화 및 항염증 효과

Background: In this study, we evaluated the antioxidant and anti-inflammatory effects of Oxalis corniculata hot water extract (OCWE) using lipopolysaccharide (LPS)-stimulated RAW264.7 cell.BRMethods and Results: Antioxidant activity was evaluated by measuring total polyphenol content, 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity, and reducing power ability. The total polyphenol content was found to be 33.06 ± 0.31 ㎎ · gallic acid equivalent/g, and each evaluation showed reduction rates of 21.93 ± 2.43%, 64.93 ± 0.83%, and 0.260 ± 0.01 at the an OCWE concentration of 400 ㎍/㎖. To evaluate the anti-inflammatory effect of OCWE, a nitric oxide (NO) assay, reverse trascription polymerase chain reaction and western blotting were performed. At 400 ㎍/㎖ concentration of OCWE, NO generation was reduced by 52.5 ± 1.37%, compared to LPS-stimulated RAW264.7 cells. OCWE also inhibited iNOS, COX-2, TNF-α, and IL-6 in at the protein ans mRNA levels in a dose-dependent manner.BRConclusions: Taken together, these results indicate that OCWE had strong antioxidant and anti-inflammatory effects. We suggest that OCWE may be an antioxidant and anti-inflammation agent in functional foods.

Ginsenoside Rk3 ameliorates Aβ-induced neurotoxicity in APP/PS1 model mice via AMPK signaling pathway

Alzheimer's disease (AD) has become a major public health problem affecting the elderly population, and there is currently no effective treatment. Although the pathogenesis of AD is unclear, neurotoxicity induced by oxidative stress plays an important role in the progression of AD. Ginseng, the root and rhizome of Panax ginseng C. A. Meyer, is used not only as an herbal medicine but also as a functional food to support bodily functions. Ginsenoside Rk3 (Rk3), the main bioactive component in ginseng, has a strong antioxidant effect and has not been reported in AD. In this study, we showed that Rk3 improved neuronal apoptosis, decreased intracellular reactive oxygen species (ROS) production and restored mitochondrial membrane potential in PC12 and primary neuronal cells. In vivo, we found that Rk3 improved spatial learning and memory deficit in precursor protein (APP)/presenilin 1 (PS1) double transgenic mouse model of AD. Additionally, Rk3 increases glutathione reductase (GSH) and superoxide dismutase (SOD) levels while inhibits malondialdehyde (MDA) production, apoptosis and activation of glial cells in APP/PS1 mice. Mechanistically, we found that the protective effect of Rk3 is in correlation with the activation of AMPK/Nrf2 signaling pathway. In conclusion, the findings of this study provide support for Rk3 as a new strategy for the treatment of AD.

Skin Wrinkles Improvement Effect for Jeju Aloe arborescens Oil Isolated from Supercritical Fluid Extraction

Purpose: In this study, the cytotoxicity and antioxidant effects of Aloe arborescens oil isolated from supercritical fluid extraction were confirmed, and an aloe oil cream was manufactured to evaluate the skin wrinkle improvement effect. Thus, we provided scientific evidence for functional cosmetic ingredients.Methods: Aloe oil was extracted from Jeju Aloe arborescens using a supercritical fluid extraction method. Aloe oil chromaticity and fatty acid analysis were determined. MTT assay and DPPH radical scavenging activity were used to assess the cell viability and antioxidant effect of NIH-3T3, HaCaT, and B16F10 cells. Additionally, we evaluated the effect of an aloe-containing cream on skin wrinkle improvement on 22 adult women 40–60 years of age.Results: Aloe oil extracted from Aloe arborescens using supercritical fluid extraction contained 0.02 g of fatty acid per 100 g, which included behenic, palmitic, α-linolenic, oleic, linoleic, and elaidic acids. The L value was 12.46±2.15, the a value was 3.73±0.26, the b value was 10.35±0.51, and the ΔE was 81.4 as a result of chromaticity. The cell viability of NIH-3T3, HaCaT, and B16F10 cells showed low cytotoxicity up to a concentration of 100 μg/mL. Aloe oil outperformed aloe supercritical extract in terms of DPPH radical scavenging activity. According to the results of a skin wrinkle improvement efficacy test, a cream containing aloe oil has a significantly high skin wrinkle improvement effect.Conclusion: We discovered that aloe oil isolated from supercritical fluid extraction has a strong antioxidant effect and significantly improves skin wrinkles.

The Protective Role of Strong Antioxidant Astaxanthin on Burn Wound and Burn-Induced Early Acute Kidney Injury through Abilities to Relieve Oxidative Stress and Inhibit Apoptosis by Modulating Mitochondrial-Apoptotic Pathways

Summary: Burns are skin damage caused by heat trauma or cold trauma (frost bite). Causes include fire, hot water, electricity, chemicals, radiation, and cold (frostbite). This damage may involve subcutaneous tissue. Burn injuries are associated with high incidence and prevalence, high risk of morbidity and mortality, resource-intensive, and costly. One of the most common complications in burn patients is acute kidney injury (AKI). The mechanism of early AKI after burn injury is multifactorial, and previous studies have mainly focused on oxidative stress injury, tubular apoptosis, and systemic or local inflammation. Previous results (from our group and others) suggested that ROS-induced oxidative stress damage and apoptosis play an important role in the development of early AKI due to burn injury, and that 24 h after burn injury are useful for observing changes in burn injury. It shows that it provides an important timeframe. Kidney function and levels of oxidative stress and apoptosis. Astaxanthin (ATX) is a naturally occurring carotenoid that is readily obtained from marine organisms and stronger antioxidant effects than other carotenoids. Given the critical role of oxidative stress and secondary renal inflammation in severe burn-induced early AKI, a protective role of ATX through its anti-inflammatory effects and potential mechanisms of action in early post-burn AKI is reasonable.

Evaluation of Phytochemical Contents and Biological Activities of Salvia officinalis and Salvia triloba Grown with Organic Farming

Salvia officinalis L., known as medicinal sage, and Salvia triloba L., known as Anatolian sage, belong to the Lamiaceae family and are species that usually grow in the Mediterranean region. In this study, it was aimed to evaluate the in vitro antidiabetic, antiobesity and antioxidant potentials of the extracts prepared by infusion technique from S. officinalis and S. triloba grown by organic farming methods. In addition, the effects of the extracts on the pancreatic cholesterol esterase enzyme were also investigated. Reverse Phase-HPLC technique was used to analyze the phytochemical contents of the extracts. At a concentration of 2 mg/mL, S. officinalis inhibited 64.69% ± 0.23, S. triloba 47.78 ± 2.11% on the α-glucosidase enzyme. Only S. triloba had an inhibitory effect on α-amylase and pancreatic lipase enzyme. On the pancreatic cholesterol esterase enzyme, inhibition values of S. triloba extract at all tested concentrations were found to be higher than S. officinalis extract. When the antioxidant potentials of the extracts were evaluated, the reducing power absorbance values were found to be the highest of the S. officinalis extract. The metal chelating capacity of both extracts at a concentration of 2 mg/mL was calculated as 100%. It was concluded that the ABTS radical scavenging activity of the extracts increased in a dose-dependent manner. With the Reverse Phase-YPSK technique, rosmarinic acid and hesperidin were found to be higher in S. officinalis extract. The presence of hesperidin in S. triloba was detected for the first time in this study. Considering all these findings, it was concluded that activity-guided isolation and in vivo activity studies should be performed because these two species grown by organic farming method have strong α-glucosidase enzyme inhibitory and antioxidant effects.

Novel preventive effect of isorhamnetin on electrical and structural remodeling in atrial fibrillation.

Isorhamnetin, a natural flavonoid, has strong antioxidant and antifibrotic effects, and a regulatory effect against Ca2+-handling. Atrial remodeling due to fibrosis and abnormal intracellular Ca2+ activities contributes to initiation and persistence of atrial fibrillation (AF). The present study investigated the effect of isorhamnetin on angiotensin II (AngII)-induced AF in mice. Wild-type male mice (C57BL/6J, 8 weeks old) were assigned to three groups: (1) control group, (2) AngII-treated group, and (3) AngII- and isorhamnetin-treated group. AngII (1000 ng/kg/min) and isorhamnetin (5 mg/kg) were administered continuously via an implantable osmotic pump for two weeks and intraperitoneally one week before initiating AngII administration, respectively. AF induction and electrophysiological studies, Ca2+ imaging with isolated atrial myocytes and HL-1 cells, and action potential duration (APD) measurements using atrial tissue and HL-1 cells were performed. AF-related molecule expression was assessed and histopathological examination was performed. Isorhamnetin decreased AF inducibility compared with the AngII group and restored AngII-induced atrial effective refractory period prolongation. Isorhamnetin eliminated abnormal diastolic intracellular Ca2+ activities induced by AngII. Isorhamnetin also abrogated AngII-induced APD prolongation and abnormal Ca2+ loading in HL-1 cells. Furthermore, isorhamnetin strongly attenuated AngII-induced left atrial enlargement and atrial fibrosis. AngII-induced elevated expression of AF-associated molecules, such as ox-CaMKII, p-RyR2, p-JNK, p-ERK, and TRPC3/6, was improved by isorhamnetin treatment. The findings of the present study suggest that isorhamnetin prevents AngII-induced AF vulnerability and arrhythmogenic atrial remodeling, highlighting its therapeutic potential as an anti-arrhythmogenic pharmaceutical or dietary supplement.

Protective effect of human umbilical cord mesenchymal stem cell derived conditioned medium in a mutant TDP-43 induced motoneuron-like cellular model of ALS

Amyotrophic lateral sclerosis (ALS) is a multi-factor neurodegenerative disease, characterized by the loss of motor neurons. TAR DNA-binding protein 43 (TDP-43) mutation, accumulation and aggregation, as well as oxidative stress are recognized as major pathological denominators and biochemical markers for ALS. Recently, human umbilical cord mesenchymal stem cell-derived conditioned medium (UC-CM) has been introduced to treat ALS patients. However, there is no research for the protective effect of UC-CM on the TDP-43 model of ALS. In this study, we evaluated the potential neuroprotective effect of UC-CM on a cellular ALS model expressing TDP-43mutant M337V, as well as its underlying mechanism. We found that 24 h UC-CM treatment could protect M337V expressing motor neurons by increasing cell viability and reducing LDH leakage. Furthermore, the aggregation of M337V, generation of ROS, malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), protein carbonyl and 8-OHdG were also reduced by UC-CM, indicating that UC-CM protected cells by reducing oxidative damage. Moreover, UC-CM significantly increased the expression of nuclear Nrf2 and its downstream enzyme HO1. The Nrf2 translocation inhibitor ML385 could inhibit the effect of UC-CM on the cell viability and aggregate of M337V. Our results suggest that UC-CM protect cells against M337V expression by its strong antioxidative effect via Nrf-2/HO-1 axis activation.

Secondary Metabolites in Fungi

Fungi are a biological family that includes multicellular and unicellular eukaryotic organisms in general. They are quite numerous and diverse. It is the second largest group of organisms on Earth after insects. Higher fungi (terrestrial fungi) currently constitute a large and efficiently untapped resource of new pharmacological crops with nutritional values are potentially powerful. Antioxidants prevent cellular damage caused by free radicals in living beings. It has been found that 36% of endophytic mushroom extracts with a high phenolic content show strong antioxidant effects. In one study, they reported that the antioxidant activities of the strains Aspergillus sp., A. niger, A. peyronelii and Chaetomium sp. ranged from 50% to 80% and that this antioxidant activity was due to their high phenolic content. In addition to the antioxidant properties of fungi, it has been shown as a result of research that they show antibacterial activity. Macrofungal β-glucans (β-1,6 glycosidic bonds and mainly β-1,3), which are known to have immunomodulatory and antitumor effects in cancer prevention, can be used in treatment strategies. At the same time, it has been shown in studies that these metabolites obtained from fungi cause fewer side effects when used in treatments, unlike chemical drugs. As a result of phytochemical research, the presence of flavonoids, anthraquinones, steroids, terpenoids, coumarins, phenols and tannins in fungal extracts in general was detected, while alkaloids and saponins were not found. It has been determined that the studies on mushrooms have gained versatile uses since they reveal secondary metabolite components with different biological activities in the structure of these group members.

A Bioengineered Quercetin-Loaded 3D Bio-Polymeric Graft for Tissue Regeneration and Repair.

Phytochemicals extracted from plant sources have potential remedial effects to cure a broad range of acute to severe illnesses and ailments. Quercetin is a flavonoid isolated from different dietary sources such as vegetables and fruits, exhibiting strong anti-inflammatory, anti-oxidative and non-toxic effects on the biological system. However, the direct uptake or administration of quercetin results in loss of functionality, poor activity, and reduced shelf-life of the bioactive component. In this regard, to improve the uptake, potential, and efficiency of natural components with prolonged storage in the host's body after administration, numerous polymer drug delivery systems have been created. In the current study, three-dimensional (3D) porous (porosity: 92%; pore size: 81 µm) bio-polymeric foaming gelatin-alginate (GA) beads were fabricated for the entrapment of quercetin as therapeutic drug molecules-gelatin-alginate-quercetin (GAQ). The GAQ beads showed a significant uptake of quercetin molecules resulting in a reduction of reduced porosity up to 64% and pore size 63 µm with a controlled release profile in the PBS medium, showing ~80% release within 24 h. Subsequently, the GAQ beads showed remarkable antioxidant effects, and 95% anti-inflammatory activities along with remarkable in vitro cell culture growth and the observed proliferation of seeded fibroblast cells. Thus, we can conclude that the consistent release of quercetin showed non-toxic effects on normal cell lines and the bioactive surface of the GAQ beads enhances cell adhesion, proliferation, and differentiation more effectively than control GA polymeric beads and tissue culture plates (TCP). In summary, these findings show that these GAQ beads act as a biocompatible 3D construct with enormous potential in medicinal administration and tissue regeneration for accelerated healing.

Analysis of Antioxidant, Antidiabetic Potential, and Corosolic Acid Content in Prunus Padus Leaves

This research was conducted to detect corosolic acid, in vitro antioxidant and antidiabetic effect of Prunus padus leaf, also called Bird cherry and is a member of Rosaceae. It is a medium-sized tree with obovate, fine serrated leaves and white flowers. According to the HPLC Chromatogram of standard corosolic acid, leaf samples of Prunus padus displayed a peak with a retention time of 9.855 min. Quantitative analysis revealed a good concentration of corosolic acid i.e 8.032 μg/20 mg d w. In vitro studies showed potent antidiabetic and antioxidant activities DPPH radical scavenging test of Prunus padus showed 91.90 per cent inhibition and standard ascorbic acid showed 82.39 per cent inhibition at 250 μg/ml concentration. Acarbose and Prunus padus both have IC50 values of 193.62 ± 0.634 μg/ ml and 114.72 ± 1.038 μg/ ml, accordingly, as determined by an alpha amylase inhibition experiment. The results demonstrate that Prunus padus possesses a good amount of corosolic acid and can be considered a natural source, which is very influential in neutralizing the reactive oxygen species and damage caused by diabetes and has strong antioxidant and antidiabetic effects.

Bio-mechanical property of skin in Psoriasis and Psorolin B

In the present paper we have investigated Psorolin B ointment for improving the bio-mechanical property of the skin. Psorolin B ointment is proprietary Siddha formulation composed of Boswellia serrata, Wrightia tinctoria, Cynodon dactylon, Hydnocarpus laurifolia and red ochre. The bio-mechanical property/elasticity of the skin is evaluated in volar forearm region by four different methods such as applying uniaxial force, centripetal force, vacuum suction and instant retraction by pinch-pull test. The findings clearly showed that Psorolin B ointment improved the skin elasticity and dexterity of the cutaneous tissue. In our previous study we have already established the elastase and collagenase inhibitory effect of Psorolin B and it also possess strong antioxidant effect. The findings are discussed in the article.

Lignin-Based Nanoparticles as Both Structural and Active Elements in Self-Assembling and Self-Healing Multifunctional Hydrogels for Chronic Wound Management.

Efficient wound healing is feasible when the dressing materials simultaneously target multiple factors causing wound chronicity, such as deleterious proteolytic and oxidative enzymes and bacterial infection. Herein, entirely bio-based multifunctional self-assembled hydrogels for wound healing were developed by simply mixing two biopolymers, thiolated hyaluronic acid (HA-SH) and silk fibroin (SF), with lignin-based nanoparticles (NPs) as both structural and functional elements. Sono-enzymatic lignin modification with natural phenolic compounds results in antibacterial and antioxidant phenolated lignin nanoparticles (PLN) capable of establishing multiple interactions with both polymers. These strong and dynamic polymer-NP interactions endow the hydrogels with self-healing and shear-thinning properties, and pH-responsive NP release is triggered at neutral to alkaline pH (7-9). Despite being a physically crosslinked hydrogel, the material was stable for at least 7 days, and its mechanical and functional properties can be tuned depending on the polymer and NP concentration. Furthermore, human skin cells in contact with the nanocomposite hydrogels for 7 days showed more than 93% viability, while the viability of clinically relevant Staphylococcus aureus and Pseudomonas aeruginosa was reduced by 99.7 and 99.0%, respectively. The hydrogels inhibited up to 52% of the activity of myeloperoxidase and matrix metalloproteinases, responsible for wound chronicity, and showed a strong antioxidant effect, which are crucial features promoting wound healing.

Regulatory effect of isovitexin on MAPK/NF-κB signal in mice with acute ulcerative colitis

The aim of this study was to investigate the anti-inflammatory effects and mechanism of isovitexin on ulcerative colitis mice and RAW264.7 cells. The results showed that isovitexin had strong antioxidant and anti-inflammatory effects, and could restore intestinal barrier integrity (p < 0.01). In addition, isovitexin inhibited the expression of MyD88, TLR4 and NF-κB p65 proteins. At the same time, isovitexin can inhibit the activation of MAPK/NF-κB signaling pathway in RAW264.7 cells. In conclusion, isovitexin has a protective effect on UC mice, and its improvement mechanism of UC might be related to MAPK/NF-κB signaling pathway.

The hepatoprotective effect of aminoguanidine in acute liver injury caused by CCl4 in rats

In this study, the hepatoprotective effect of aminoguanidine in acute liver damage caused by carbon tetrachloride-CCl4 at a dose of 1 mL/kg, i.p. was investigated in experimental rats. Ten days of preventive treatment with aminoguanidine before exposure to toxic CCl4, at a dose of 150 mg/kg, i.p., led to significant reduction in biochemical markers of acute liver injury-AST(p < 0.001), ALT (p < 0.01), SDH (p < 0.05) and reduction in pro-oxidative markers-H2O2 (p < 0.05), TOS (p < 0.01), TBARS, and LOOH (p < 0.001) in relation to rats treated only CCl4. Treatment with aminoguanidine resulted in a significant reduction in the consumption of antioxidant-GR (p < 0.01), GST, GPx, GSH (p < 0.001), and a decrease in pro-inflammatory-TNF-α (p < 0.01), IL-1β, IL-6, NO and NGAL (p < 0.001) markers relative to animals exposed to CCl4 alone. Also, aminoguanidine pre-treatment leads to an increase in arginase activity (p < 0.001), and a decrease in citrulline concentration (p < 0.01), as well as polyamine catabolism enzyme activity-putrescin oxidase and spermine oxidase (p < 0.001) in comparison to the CCl4 group. Aminoguanidine led to a striking reduction of the necrotic field (p < 0.001), and a significant increase in the number of apoptotic hepatocytes (p < 0.001), as well as the proapoptotic markers-BAX and Caspase-3 (p < 0.05), compared to CCl4. The hepatoprotective mechanisms in CCl4 induce hepatotoxicity of aminoguanidine are based on the strong antioxidant effects, inhibition of pro-oxidative and pro-inflammatory mediators, as well as induction of damaged hepatocytes into apoptosis.

Potential Therapeutic Approach of Melatonin against Omicron and Some Other Variants of SARS-CoV-2.

The Omicron variant (B.529) of COVID-19 caused disease outbreaks worldwide because of its contagious and diverse mutations. To reduce these outbreaks, therapeutic drugs and adjuvant vaccines have been applied for the treatment of the disease. However, these drugs have not shown high efficacy in reducing COVID-19 severity, and even antiviral drugs have not shown to be effective. Researchers thus continue to search for an effective adjuvant therapy with a combination of drugs or vaccines to treat COVID-19 disease. We were motivated to consider melatonin as a defensive agent against SARS-CoV-2 because of its various unique properties. Over 200 scientific publications have shown the significant effects of melatonin in treating diseases, with strong antioxidant, anti-inflammatory, and immunomodulatory effects. Melatonin has a high safety profile, but it needs further clinical trials and experiments for use as a therapeutic agent against the Omicron variant of COVID-19. It might immediately be able to prevent the development of severe symptoms caused by the coronavirus and can reduce the severity of the infection by improving immunity.

Avenanthramide-C Activates Nrf2/ARE Pathway and Inhibiting Ferroptosis Pathway to Improve Cognitive Dysfunction in Aging Rats.

Postoperative neurocognitive impairment (POCD) is a common complication after surgery and anesthesia, especially in elderly patients. Avenanthramide-C (AVC) test is a vascular endothelial cell adhesion molecule inhibitor with strong anti-inflammatory and antioxidant effects. The aim of this study was to investigate the effect and mechanism of AVC on POCD in aged rats to clarify the effect of AVC on POCD in aged rats. The aging rat model was established by continuous 200mg/kg propofol anesthesia. Repeated propofol anesthesia could severely impair spatial learning ability, memory and cognitive function, and could promote hippocampal apoptosis, oxidative stress injury, neuroinflammation and ferroptosis in aging rats. In addition, AVC not only improved cognitive dysfunction, but also significantly inhibited apoptosis, neuroinflammatory response, ferroptosis and oxidative stress level in the hippocampus of aging rats induced by repeated anesthesia. Further mechanistic studies manifested that the above protective effects of AVC on aging rats induced by repeated propofol anesthesia may be achieved by activating Nrf2/ARE pathway activity. AVC pretreatment has a preventive effect on cognitive dysfunction induced by repeated propofol anesthesia in aging rats, and the preventive effect of AVC may be realized by activating the Nrf2/ARE signaling pathway activity. Our results demonstrate that AVC preconditioning reduces postoperative neuronal loss and neuroinflammation, activates the Nrf2/ARE pathway, reduces oxidative stress injury, and improves POCD in aged rats.