Selenium nanoparticles and metformin ameliorate streptozotocin-instigated brain oxidative-inflammatory stress and neurobehavioral alterations in rats

Efficacy of curcumin-selenium nanoemulsion in alleviating oxidative damage induced by aluminum chloride in a rat model of Alzheimer's disease

Alzheimer's disease (AD) is a common neurological disorder primarily affecting older adults. A hallmark of this condition is the generation of reactive oxygen species (ROS), leading to increased oxidative stress and cellular damage. Treatment with a curcumin-selenium nanoemulsion has been shown to enhance behavioural performance and mitigate degenerative changes induced by aluminium chloride (AlCl3). This nanoemulsion also reduced the activity of acetylcholinesterase (AChE) and lowered levels of key proteins, including Aβ, p53, tau, nuclear factor erythroid 2-related factor 2 (Nrf2), and tumour necrosis factor-alpha (TNF-α). Additionally, it significantly decreased nitric oxide (NO) levels in the brain while enhancing the activity of catalase (CAT) and superoxide dismutase (SOD). The study highlights the antioxidant and anti-inflammatory properties of the curcumin-selenium nanoemulsion, suggesting its potential as a therapeutic option for alleviating AD induced by AlCl3. These results are further supported by improvements in the histological structure of the cortex and hippocampus, as well as enhanced immunohistochmical assessment of glial fibrillary acidic protein (GFAP). Cur- Se-nanoemulsion, the current drug delivery technology, may lower the amount of amyloid-β in AD rat brain and considerably ameliorate the memory deficit that improve therapy efficacy in AD lesions.

A Comparative Study of Nanoconjugates of a Synthetic and a Natural Drug Against T2DM-Induced Cognitive Dysfunction

Type II Diabetes Mellitus (T2DM) is one of the risk factors for the development of dementia leading to cognitive dysfunctions. The present study evaluates the efficacy of a synthetic drug (Vildagliptin, VLD) and a natural glycosidic compound (Hesperidin, HSP) against T2DM-induced cognitive dysfunction in rats. The drugs were conjugated with metal nanoparticles like gold (Au) and selenium (Se) to enhance their efficacy. The synthesis of the monometallic and bimetallic nanoparticles of VLD and HSP was established via the turkevich method and characterised by different spectroscopical techniques like UV (Ultraviolet)-visible, FTIR (Fourier Transform Infrared Spectroscopy), zeta potential, particle size, HR-TEM (High Resolution Transmission Electron Microscopy), SAED (Selected Area Electron Diffraction) and SEM-EDX (Scanning Electron Microscopy with Energy Dispersive X-ray Analysis). Both Streptozotocin (STZ) of 65 mg/kg (Group I-X) and Alloxan (ALX) of 150 mg/kg (Group I-X) were injected into 120 Wistar rats to induce cognitive dysfunction. After the induction, the BGL levels were evaluated and rats with BGL > 250 mg/dl were used in the study. Then the test drug and nanoformulations were administered for 21 days. Neurobehavioral assessment, antioxidant studies, and estimation of AChE (acetylcholinesterase) and nitrite levels were done. The VLD and HSP with its nanoconjugates significantly attenuated the effect of STZ and ALX by improving the memory and learning function in Y-maze, radial arm maze (RAM), and elevated plus maze (EPM), increased antioxidant levels of SOD (superoxide dismutase), CAT (catalase), and GSH (glutathione); decreased lipid peroxidation and reduced the AChE and nitrite levels in the rat brain. The bimetallic nanoconjugates of both VLD and HSP were more effective than the monometallic forms of VLD and HSP. However, VLD and its nanoconjugates exhibited better neuroprotective activity than HSP and its nanoconjugates in STZ and ALX animal models. VLD and its nanoformulations were more effective against long-term memory than HSP and its nanoconjugates. Both VLD and HSP may be a potential lead for cognitive and neurodegenerative diseases.

Neuroprotective Role of Selenium Nanoparticles Against Behavioral, Neurobiochemical and Histological Alterations in Rats Subjected to Chronic Restraint Stress

Chronic stress induces changes in the prefrontal cortex and hippocampus. Selenium nanoparticles (SeNPs) showed promising results in several neurological animal models. The implementation of SeNPs in chronic restraint stress (CRS) remains to be elucidated. This study was done to determine the possible protective effects of selenium nanoparticles on behavioral changes and brain oxidative stress markers in a rat model of CRS. 50 rats were divided into three groups; control group (n = 10), untreated CRS group (n = 10) and CRS-SeNPs treated group (n = 30). Restraint stress was performed 6 h./day for 21 days. Rats of CRS-SeNPs treated group received 1, 2.5 or 5 mg/kg SeNPs (10 rats each) by oral gavage for 21 days. Rats were subjected to behavioral assessments and then sacrificed for biochemical and histological analysis of the prefrontal cortex and hippocampus. Prefrontal cortical and hippocampal serotonin levels, oxidative stress markers including malondialdehyde (MDA), reduced glutathione (GSH) and glutathione peroxidase (GPx), tumor necrosis factor alpha (TNF-α) and caspase-3 were assessed. Accordingly, different doses of SeNPs showed variable effectiveness in ameliorating disease parameters, with 2.5 mg/kg dose of SeNPs showing the best improving results in all studied parameters. The present study exhibited the neuroprotective role of SeNPs in rats subjected to CRS and proposed their antioxidant, anti-inflammatory and anti-apoptotic effects as the possible mechanism for increased prefrontal cortical and hippocampal serotonin level, ameliorated anxiety-like and depressive-like behaviors and improved prefrontal cortical and hippocampal histological architecture.

Metformin attenuates white matter injury in neonatal mice through activating NRF2/HO-1/NF-κB pathway

White matter injury (WMI) is a major form of brain injury that occurs in preterm infants and develops into lifelong disabilities, including cerebral palsy, impaired cognitive function, and psychiatric disorders. Metformin (MET) has been reported to have neuroprotective effects. However, whether MET is responsible for neuroprotection against WMI remains unclear. In this study, we established a WMI model in neonatal mice to explore the neuroprotective effects of MET and attempted to elucidate its potential mechanisms. Our results showed that MET increased the expression of myelin basic protein (MBP), oligodendrocyte transcription factor 2 (Olig2), and CC1, improved the thickness and density of the myelin sheath, and reduced oxidative stress and microglial infiltration after chronic hypoxia induction. Moreover, MET improved memory, learning, and motor abilities as well as relieved anxiety-like behaviors in mice with WMI. These protective effects of MET may involve the upregulation of the nuclear factor erythroid 2-related factor 2 (NRF2)/heme oxygenase-1(HO-1)/NF-κB pathway related protein expressions. In addition, the NRF2 inhibitor ML385 could significantly reverse the effects of MET. In conclusion, this study suggested that MET attenuated chronic hypoxia-induced WMI through activating the NRF2/HO-1/NF-κB pathway, indicating that MET might be a promising therapeutic option for WMI.

Exploring the Link between Oxidative Stress, Selenium Levels, and Obesity in Youth

Obesity is a worldwide increasing concern. Although in adults this is easily estimated with the body mass index, in children, who are constantly growing and whose bodies are changing, the reference points to assess weight status are age and gender, and need corroboration with complementary data, making their quantification highly difficult. The present review explores the interaction spectrum of oxidative stress, selenium status, and obesity in children and adolescents. Any factor related to oxidative stress that triggers obesity and, conversely, obesity that induces oxidative stress are part of a vicious circle, a complex chain of mechanisms that derive from each other and reinforce each other with serious health consequences. Selenium and its compounds exhibit key antioxidant activity and also have a significant role in the nutritional evaluation of obese children. The balance of selenium intake, retention, and metabolism emerges as a vital aspect of health, reflecting the complex interactions between diet, oxidative stress, and obesity. Understanding whether selenium status is a contributor to or a consequence of obesity could inform nutritional interventions and public health strategies aimed at preventing and managing obesity from an early age.

Selenium Species in Diabetes Mellitus Type 2

Selenium is an important trace element for humans and animals as it plays a key role in several major metabolic pathways. Several studies were conducted to better understand the role of selenium against diabetes mellitus (DM), particularly type 2 (T2DM), but the obtained conclusions are contradictory. A simple linear relationship does not exist between the risk of T2DM and selenium levels but is best represented in a dose-dependent manner, getting often the U-graph. This relation also depends on selenium chemical forms that are present in a diet or supplements. Both too low and too high selenium intakes could increase the risk of diabetes. Moreover, the baseline status of Se should be taken into consideration to avoid over-supplementation. The focus of this brief overview is to report the recent updates concerning selenium participation in diabetes mellitus.

Pegylated polymeric micelles of boswellic acid-selenium mitigates repetitive mild traumatic brain injury: Regulation of miR-155 and miR-146a/BDNF/ Klotho/Foxo3a cue

This study aims to explore the protective machinery of pegylated polymeric micelles of boswellic acid-selenium (PMBS) against secondary neuronal damage triggered by mild repetitive traumatic brain injury (RTBI). After PMBS characterization in terms of particle size, size distribution, zeta potential, and transmission electronic microscopy, the selected formula was used to investigate its potency against experimental RTBI. Five groups of rats were used; group 1 (control) and the other four groups were subjected to RTBI. Groups 2 was RTBI positive control, while 3, 4, and 5 received boswellic acid (BSA), selenium (SEL), and PMBS, respectively. The open-field behavioral test was used for behavioral assessment. Subsequently, brain tissues were utilized for hematoxylin and eosin staining, Nissl staining, Western blotting, and ELISA in addition to evaluating microRNA expression (miR-155 and miR-146a). The behavioral changes, oxidative stress, and neuroinflammation triggered by RTBI were all improved by PMBS. Moreover, PMBS mitigated excessive glutamate-induced excitotoxicity and the dysregulation in miR-155 and miR-146a expression. Besides, connexin43 (Cx43) expression as well as klotho and brain-derived neurotrophic factor (BDNF) were upregulated with diminished neuronal cell death and apoptosis because of reduced Forkhead Box class O3a(Foxo3a) expression in the PMBS-treated group. The current study has provided evidence of the benefits produced by incorporating BSA and SEL in PEGylated polymeric micelles formula. PMBS is a promising therapy for RTBI. Its beneficial effects are attributed to the manipulation of many pathways, including the regulation of miR-155 and miR-146a expression, as well as the BDNF /Klotho/Foxo3a signaling pathway.

Selenium Nanoparticles as Neuroprotective Agents: Insights into Molecular Mechanisms for Parkinson's Disease Treatment

Oxidative stress and the accumulation of misfolded proteins in the brain are the main causes of Parkinson's disease (PD). Several nanoparticles have been used as therapeutics for PD. Despite their therapeutic potential, these nanoparticles induce multiple stresses upon entry. Selenium (Se), an essential nutrient in the human body, helps in DNA formation, stress control, and cell protection from damage and infections. It can also regulate thyroid hormone metabolism, reduce brain damage, boost immunity, and promote reproductive health. Selenium nanoparticles (Se-NPs), a bioactive substance, have been employed as treatments in several disciplines, particularly as antioxidants. Se-NP, whether functionalized or not, can protect mitochondria by enhancing levels of reactive oxygen species (ROS) scavenging enzymes in the brain. They can also promote dopamine synthesis. By inhibiting the aggregation of tau, α-synuclein, and/or Aβ, they can reduce the cellular toxicities. The ability of the blood-brain barrier to absorb Se-NPs which maintain a healthy microenvironment is essential for brain homeostasis. This review focuses on stress-induced neurodegeneration and its critical control using Se-NP. Due to its ability to inhibit cellular stress and the pathophysiologies of PD, Se-NP is a promising neuroprotector with its anti-inflammatory, non-toxic, and antimicrobial properties.

Selenium Nanoparticles in Protecting the Brain from Stroke: Possible Signaling and Metabolic Mechanisms

Strokes rank as the second most common cause of mortality and disability in the human population across the world. Currently, available methods of treating or preventing strokes have significant limitations, primarily the need to use high doses of drugs due to the presence of the blood-brain barrier. In the last decade, increasing attention has been paid to the capabilities of nanotechnology. However, the vast majority of research in this area is focused on the mechanisms of anticancer and antiviral effects of nanoparticles. In our opinion, not enough attention is paid to the neuroprotective mechanisms of nanomaterials. In this review, we attempted to summarize the key molecular mechanisms of brain cell damage during ischemia. We discussed the current literature regarding the use of various nanomaterials for the treatment of strokes. In this review, we examined the features of all known nanomaterials, the possibility of which are currently being studied for the treatment of strokes. In this regard, the positive and negative properties of nanomaterials for the treatment of strokes have been identified. Particular attention in the review was paid to nanoselenium since selenium is a vital microelement and is part of very important and little-studied proteins, e.g., selenoproteins and selenium-containing proteins. An analysis of modern studies of the cytoprotective effects of nanoselenium made it possible to establish the mechanisms of acute and chronic protective effects of selenium nanoparticles. In this review, we aimed to combine all the available information regarding the neuroprotective properties and mechanisms of action of nanoparticles in neurodegenerative processes, especially in cerebral ischemia.

Ameliorative and Neuroprotective Effect of Core-Shell Type Se@Au Conjugated Hesperidin Nanoparticles in Diabetes-Induced Cognitive Impairment

Diabetes mellitus is the most chronic metabolic ailment characterized by insulin deficiency leading to aberrant cognitive dysfunction in later stages. Hesperidin is a bioflavonoid, having different pharmacological activities, but its poor water solubility and short plasma half-life restrict its applications in the clinical field. So, the hesperidin was conjugated with gold, selenium, and core-shell bimetallic nanoparticles of gold and selenium. Different spectroscopic methods characterized the synthesized monometallic and bimetallic nanoparticles. The rats were injected with streptozotocin to induce cognitive dysfunction, followed by administering HSP, HSP-Au NPs, HSP-Se NPs, and Se@Au-HSP NPs daily for 21 days. Then, the neurobehavioral studies, oxidative stress parameters, AChE and nitrite levels, the content of amyloid-β42, and inflammatory mediators were accessed to evaluate the effect of the nanoparticles against the STZ rat model. The results showed a significant increase in oxidative stress, AChE activity, amyloid-β42, nitrite levels, and neuroinflammation by upregulating the inflammatory cytokines in the streptozotocin-administered rat brain. The HSP, HSP-Au NPs, HSP-Se NPs, and Se@Au-HSP NPs effectively reversed all these effects of streptozotocin. However, the bimetallic nanoparticle Se@Au-HSP NPs revealed better neuroprotective action than HSP-Au NPs and HSP-Se NPs. Hesperidin-conjugated bimetallic nanoparticles improved learning and memory in the STZ rat model and may be an alternative approach for neurodegenerative diseases, including Alzheimer's disease.

New insights toward molecular and nanotechnological approaches to antidiabetic agents for Alzheimer's disease

Alzheimer's disease (AD) is a chronic neurodegenerative disorder affecting a major class of silver citizens. The disorder shares a mutual relationship on account of its cellular and molecular pathophysiology with type-II diabetes mellitus (DM). Chronic DM increases the risk for AD. Emerging evidence recommended that resistance in insulin production develops cognitive dysfunction, which generally leads to AD. Repurposing of antidiabetic drugs can be effective in preventing and treatment of the neurodegenerative disorder. Limitations of antidiabetic drugs restrict the repurposing of the drugs for other disorders. Therefore, nanotechnological intervention plays a significant role in the treatment of neurological disorders. In this review, we discuss the common cellular and molecular pathophysiologies between AD and type-II DM, the relevance of in vivo models of type II DM in the study of AD, and the repurposing of antidiabetic drugs and the nanodelivery systems of antidiabetic drugs against AD.

Novel iodoquinazolinones bearing sulfonamide moiety as potential antioxidants and neuroprotectors

In a search for new antioxidants, a set of new iodoquinazolinone derivatives bearing benzenesulfonamide moiety and variable acetamide pharmacophores 5-17 were designed and synthesized. The structures of the synthesized compounds were confirmed based on spectral data. Compounds 5-17 were screened using in vitro assay for their antioxidant potential and acetylcholinesterase (AChE) inhibitory activity. The 2-(6-iodo-4-oxo-3-(4-sulfamoylphenyl)-3,4-dihydroquinazolin-2-ylthio)-N-(pyrazin-2-yl) acetamide 14 was the most active scaffold with potent AChE inhibitory activity. Compound 14 showed relative safety with a median lethal dose of 300 mg/kg (LD50 = 300 mg/kg), in an acute toxicity study. The possible antioxidant and neuroprotective activities of 14 were evaluated in irradiated mice. Compound 14 possessed in vivo AChE inhibitory activity and was able to modify the brain neurotransmitters. It was able to cause mitigation of gamma radiation-induced oxidative stress verified by the decline in Myeloperoxidase (MPO) and increase of glutathione (GSH) levels. Also, 14 restored the alterations in behavioral tests. Molecular docking of 14 was performed inside MPO and AChE active sites and showed the same binding interactions as that of the co-crystallized ligands considering the binding possibilities and energy scores. These findings would support that 14 could be considered a promising antioxidant with a neuromodulatory effect.

Metformin beyond an anti-diabetic agent: A comprehensive and mechanistic review on its effects against natural and chemical toxins

In addition to the anti-diabetic effect of metformin, a growing number of studies have shown that metformin has some exciting properties, such as anti-oxidative capabilities, anticancer, genomic stability, anti-inflammation, and anti-fibrosis, which have potent, that can treat other disorders other than diabetes mellitus. We aimed to describe and review the protective and antidotal efficacy of metformin against biologicals, chemicals, natural, medications, pesticides, and radiation-induced toxicities. A comprehensive search has been performed from Scopus, Web of Science, PubMed, and Google Scholar databases from inception to March 8, 2023. All in vitro, in vivo, and clinical studies were considered. Many studies suggest that metformin affects diseases other than diabetes. It is a radioprotective and chemoprotective drug that also affects viral and bacterial diseases. It can be used against inflammation-related and apoptosis-related abnormalities and against toxins to lower their effects. Besides lowering blood sugar, metformin can attenuate the effects of toxins on body weight, inflammation, apoptosis, necrosis, caspase-3 activation, cell viability and survival rate, reactive oxygen species (ROS), NF-κB, TNF-α, many interleukins, lipid profile, and many enzymes activity such as catalase and superoxide dismutase. It also can reduce the histopathological damages induced by many toxins on the kidneys, liver, and colon. However, clinical trials and human studies are needed before using metformin as a therapeutic agent against other diseases.

Biosynthesized Selenium Nanoparticles Using Epigallocatechin Gallate Protect against Pentylenetetrazole-Induced Acute Epileptic Seizures in Mice via Antioxidative, Anti-Inflammatory, and Anti-Apoptotic Activities

Several negative outcomes are associated with current anti-epileptic medications. Epigallocatechin gallate (EGCG) is a plant-derived compound called catechin and has many medicinal activities, such as anti-inflammatory and antioxidant activities. Biosynthesized selenium nanoparticles are also showing their neuroprotective effect. The anti-epileptic effect of EGCG, alone or with SeNPs, is still debated. Here, we aimed to investigate the potential anti-seizure effect of biosynthesized SeNPs using EGCG (EGCG-SeNPs) against epileptic seizures and hippocampal damage, which is enhanced by pentylenetetrazole (PTZ) injection in mice. Mice were grouped as follows: control; PTZ-exposed group (epileptic model); EGCG + PTZ-treated group; sodium selenite (Na₂SeO₃) + PTZ-treated group; EGCG-SeNPs + PTZ-treated group; and valproic acid (VPA) + PTZ-treated group. EGCG-SeNPs administration showed anti-epileptic activity by increasing the latency time and reducing the seizure duration following the PTZ injection. Additionally, EGCG-SeNPs counteracted the PTZ-induced changes in oxidants and antioxidants. Moreover, EGCG-SeNPs inhibited the inflammatory response by suppressing the release of pro-inflammatory cytokines and decreasing the immunoreactivity of the glial fibrillary acidic protein and mRNA expression of glutamate receptor subunit zeta-1 (NMDAR; Grin1), showing their inhibitory effect on epilepsy-associated inflammation. Moreover, EGCG-SeNPs reduced PTZ-induced neuronal apoptosis, as indicated by a reduction in the levels of pro-apoptotic proteins and an elevation of the anti-apoptotic protein. Moreover, EGCG-SeNPs administration significantly modulated the PTZ-induced changes in monoamine levels and acetylcholinesterase activity in the hippocampal tissue. The obtained findings suggest the anti-seizure activity of EGCG-SeNPs via their antioxidant, anti-inflammatory, and anti-apoptotic effects, along with their neuromodulatory effect.

Neuro-amelioration of Ficus lyrata (fiddle-leaf fig) extract conjugated with selenium nanoparticles against aluminium toxicity in rat brain: relevance to neurotransmitters, oxidative, inflammatory, and apoptotic events

Aluminium is a non-essential metal, and its accumulation in the brain is linked with potent neurotoxic action and the development of many neurological diseases. This investigation, therefore, intended to examine the antagonistic efficacy of Ficus lyrata (fiddle-leaf fig) extract (FLE) conjugated with selenium nanoparticles (FLE-SeNPs) against aluminium chloride (AlCl3)-induced hippocampal injury in rats. Rats were allocated to five groups: control, FLE, AlCl3 (100 mg/kg), AlCl3 + FLE (100 mg/kg), and AlCl3 + FLE-SeNPs (0.5 mg/kg). All agents were administered orally every day for 42 days. The result revealed that pre-treated rats with FLE-SeNPs showed markedly lower acetylcholinesterase and Na+/K+-ATPase activities in the hippocampus than those in AlCl3 group. Additionally, FLE-SeNPs counteracted the oxidant stress-mediated by AlCl3 by increasing superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione contents in rat hippocampus. Besides, the formulated nanoparticles decreased the hippocampal malondialdehyde, carbonyl protein, and nitric oxide levels of AlCl3-exposed animals. Furthermore, FLE-SeNPs attenuated neural tissue inflammation, as demonstrated by decreased interleukin-1 beta, interleukin-6, nuclear factor kappa B, and glial fibrillary acidic protein. Remarkable anti-apoptotic action was exerted by FLE-SeNPs by increasing B cell lymphoma 2 and decreasing caspase-3 and Bcl-2-associated-X protein in AlCl3-exposed rats. The abovementioned results correlated well with the hippocampal histopathological findings. Given these results, SeNPs synthesized with FLE imparted a remarkable neuroprotective action against AlCl3-induced neurotoxicity by reversing oxidative damage, neuronal inflammation, and apoptosis in exposed rats.

Is metformin neuroprotective against diabetes mellitus-induced neurodegeneration? An updated graphical review of molecular basis

Diabetes mellitus (DM) is a metabolic disease that activates several molecular pathways involved in neurodegenerative disorders. Metformin, an anti-hyperglycemic drug used for treating DM, has the potential to exert a significant neuroprotective role against the detrimental effects of DM. This review discusses recent clinical and laboratory studies investigating the neuroprotective properties of metformin against DM-induced neurodegeneration and the roles of various molecular pathways, including mitochondrial dysfunction, oxidative stress, inflammation, apoptosis, and its related cascades. A literature search was conducted from January 2000 to December 2022 using multiple databases including Web of Science, Wiley, Springer, PubMed, Elsevier Science Direct, Google Scholar, the Core Collection, Scopus, and the Cochrane Library to collect and evaluate peer-reviewed literature regarding the neuroprotective role of metformin against DM-induced neurodegenerative events. The literature search supports the conclusion that metformin is neuroprotective against DM-induced neuronal cell degeneration in both peripheral and central nervous systems, and this effect is likely mediated via modulation of oxidative stress, inflammation, and cell death pathways.

Metformin mitigates amyloid β1-40-induced cognitive decline via attenuation of oxidative/nitrosative stress and neuroinflammation

Metformin is an antidiabetic medicine widely used for management of type 2 diabetes with neuroprotective effects and promising potential to attenuate cognitive impairment. The efficacy of metformin in attenuation of Alzheimer's disease (AD) pathology has not been well-documented. Thus, this study was designed to assess protective effect of metformin against Aβ_1-40-instigared cognitive impairment. After intra-CA1 microinjection of aggregated Aβ_1-40, rats received oral metformin (50 and/or 200 mg/kg/day) for two weeks. Cognition function was analyzed in various behavioral tasks besides measurement of hippocampal oxidative stress, apoptosis, and inflammation along with H&E staining and 3-nitrotyrosine (3-NT) immunohistochemistry. Obtained data showed significant improvement of discrimination score in novel object recognition test, higher alternation score in Y maze, greater latency in passive avoidance task, and lower working and reference memory errors in radial arm maze in metformin-treated Aβ-injured group. Moreover, metformin treatment attenuated hippocampal levels of nitrite, MDA, protein carbonyl, ROS, TNFα, GFAP, DNA fragmentation intensity, caspase 3 activity, AChE activity, and increased SOD activity and level of IL-10 as an anti-inflammatory factor. In addition, metformin treatment was associated with lower CA1 neuronal loss and it also decreased intensity of 3-NT immunoreactivity as an indicator of nitrosative stress. Taken together, obtained findings showed neuroprotective and anti-dementia property of metformin in male rats and this may have potential benefit in attenuation of cognitive decline and related complications in patients with neurodegenerative disorders such as AD besides diabetes mellitus.

Biogenic Selenium Nanoparticles in Biomedical Sciences: Properties, Current Trends, Novel Opportunities and Emerging Challenges in Theranostic Nanomedicine

Selenium is an important dietary supplement and an essential trace element incorporated into selenoproteins with growth-modulating properties and cytotoxic mechanisms of action. However, different compounds of selenium usually possess a narrow nutritional or therapeutic window with a low degree of absorption and delicate safety margins, depending on the dose and the chemical form in which they are provided to the organism. Hence, selenium nanoparticles (SeNPs) are emerging as a novel therapeutic and diagnostic platform with decreased toxicity and the capacity to enhance the biological properties of Se-based compounds. Consistent with the exciting possibilities offered by nanotechnology in the diagnosis, treatment, and prevention of diseases, SeNPs are useful tools in current biomedical research with exceptional benefits as potential therapeutics, with enhanced bioavailability, improved targeting, and effectiveness against oxidative stress and inflammation-mediated disorders. In view of the need for developing eco-friendly, inexpensive, simple, and high-throughput biomedical agents that can also ally with theranostic purposes and exhibit negligible side effects, biogenic SeNPs are receiving special attention. The present manuscript aims to be a reference in its kind by providing the readership with a thorough and comprehensive review that emphasizes the current, yet expanding, possibilities offered by biogenic SeNPs in the biomedical field and the promise they hold among selenium-derived products to, eventually, elicit future developments. First, the present review recalls the physiological importance of selenium as an oligo-element and introduces the unique biological, physicochemical, optoelectronic, and catalytic properties of Se nanomaterials. Then, it addresses the significance of nanosizing on pharmacological activity (pharmacokinetics and pharmacodynamics) and cellular interactions of SeNPs. Importantly, it discusses in detail the role of biosynthesized SeNPs as innovative theranostic agents for personalized nanomedicine-based therapies. Finally, this review explores the role of biogenic SeNPs in the ongoing context of the SARS-CoV-2 pandemic and presents key prospects in translational nanomedicine.

An Approach to Evaluate the Effective Cytoplasmic Concentration of Bioactive Agents Interacting with a Selected Intracellular Target Protein

To compare the effectiveness of various bioactive agents reversibly acting within a cell on a target intracellular macromolecule, it is necessary to assess effective cytoplasmic concentrations of the delivered bioactive agents. In this work, based on a simple equilibrium model and the cellular thermal shift assay (CETSA), an approach is proposed to assess effective concentrations of both a delivered bioactive agent and a target protein. This approach was tested by evaluating the average concentrations of nuclear factor erythroid 2-related factor 2 (Nrf2) and Kelch-like ECH-associated-protein 1 (Keap1) proteins in the cytoplasm for five different cell lines (Hepa1, MEF, RAW264.7, 3LL, and AML12) and comparing the results with known literature data. The proposed approach makes it possible to analyze both binary interactions and ternary competition systems; thus, it can have a wide application for the analysis of protein-protein or molecule-protein interactions in the cell. The concentrations of Nrf2 and Keap1 in the cell can be useful not only in analyzing the conditions for the activation of the Nrf2 system, but also for comparing the effectiveness of various drug delivery systems, where the delivered molecule is able to interact with Keap1.

Role of melatonin and quercetin as countermeasures to the mitochondrial dysfunction induced by titanium dioxide nanoparticles

AIM

Due to the growing commercialization of titanium dioxide nanoparticles (TNPs), it is necessary to use these particles in a manner that is safe, healthy and environmental friendly. Through reactive oxygen species (ROS) generation, it has been discovered that TNPs have a harmful effect on the brain. The aim of this study is to provide valuable insights into the possible mechanisms of TNPs induced mitochondrial dysfunction in brain and its amelioration by nutraceuticals, quercetin (QR) and melatonin (Mel) in in vitro and in vivo conditions.

MATERIALS AND METHODS

Whole brain mitochondrial sample was used for in-vitro evaluation. Pre-treatment of QR (30 μM) and Mel (100 μM) at 25 °C for 1 h was given prior to TNPs (50 μg/ml) exposure. For in-vivo study, male Wistar rats were divided into four groups. Group I was control and group II was exposed to TNPs (5 mg/kg b.wt., i.v.). QR (5 mg/kg b.wt.) and Mel (5 mg/kg b.wt.) were given orally as pre-treatment in groups III and IV, respectively. Biochemical parameters, neurobehavioural paradigms, mitochondrial respiration, neuronal architecture assessment were assessed.

KEY FINDINGS

QR and Mel restored the mitochondrial oxidative stress biomarkers in both the studies. Additionally, these nutraceuticals resuscitated the neurobehavioural alterations and restored the neuronal architecture alterations in TNPs exposed rats. The mitochondrial dysfunction induced by TNPs was also ameliorated by QR and Mel by protecting the mitochondrial complex activity and mitochondrial respiration rate.

SIGNIFICANCE

Results of the study demonstrated that QR and Mel ameliorated mitochondrial mediated neurotoxic effects induced by TNPs exposure.

Testicular Effect of Selenium Nanoparticles on Monosodium Glutamate Induced Alteration in Male Albino Rats

<b>Background and Objective:</b> The flavor enhancer Monosodium Glutamate (MSG) is mostly utilized in Asian and West African cuisines, especially in West African and Asian dishes. However, due to its availability, largely without labeling, in many food products, unintentional overuse of this food additive may occur. The objective of this study was to find out how selenium nanoparticles affected the toxicity of MSG in male albino rats' testicles. <b>Materials and Methods:</b> As 35 Wistar male rats partitioned into 5 groups: G1: Control rats, G2: Received Se-NPs at 0.4 mg kg¹ b.wt., orally, G3: Injected with MSG at a daily dose of 4 g kg¹ b.wt., intraperitoneally (IP), G4: Ingested a daily oral dose of Se-NPs for 7 successive days and on the 7th day, received the first dose of MSG IP 4 g kg¹ b.wt., then received both treatments till the end of the study and G5: Administered a daily oral dose of 4 g kg¹ MSG, followed by Se-NPs at a daily dose of 0.4 mg kg¹ b.wt., the experiment continued for 28 days. Serum testosterone hormone, Follicle Stimulating Hormone (FSH), Luteinizing Hormone (LH), the levels of serum lipid peroxidation (MDA), reduced Glutathione (GSH), Glutathione Peroxidase (GSH-Px), superoxide dismutase (SOD) and Lactate Dehydrogenase (LDH) were estimated and samples from testis were separated for histological analysis. <b>Results:</b> The MSG treatment induced a significant decline in the values of serum testosterone, FSH, LH, GSH, GSH-Px and SOD. It also increased the values of serum MDA and LDH and spermatic arrest. While, the administration of Se-NPs orally before MSG treatment resulted in a decline in the values of serum MDA and LDH, an elevation in the values of serum GSH, GSH-PX and SOD, testosterone, FSH, LH and reappearance of sperm. <b>Conclusion:</b> The use of Se-NPs as a protector exhibited more improvement in values of estimated hormones and oxidative stress markers than using it as a therapy.

Chitosan-Encapsulated Nano-selenium Targeting TCF7L2, PPARγ, and CAPN10 Genes in Diabetic Rats

This study investigates the antidiabetic and antioxidant potential of chitosan-encapsulated selenium nanoparticles in streptozotocin-induced diabetic model. Glibenclamide was used as a reference antidiabetic drug. Forty-eight adult male Wistar rats were used along the study and divided equally into 6 groups of (I) normal control, (II) chitosan-encapsulated selenium nanoparticles (CTS-SeNPs), (III) glibenclamide, (IV) streptozotocin (STZ), (V) STZ + CTS-SeNPs, and (VI) STZ + Glib. The animals were sacrificed on the 35th day of the experiment. Serum glucose, insulin, IGF-1, ALT, AST, CK-MB, oxidative stress, lipid profile, and inflammatory parameters were subsequently assessed. Also, the expression level of TCF7L2, CAPN10, and PPAR-γ genes were evaluated using qPCR. In addition, histopathological studies on pancreatic tissue were carried out. The results revealed that STZ induced both diabetes and oxidative stress in normal rats, manifested by the significant changes in the studied parameters and in the physical structure of pancreatic tissue. Oral administration of CTS-SeNPs or Glib results in a significant amelioration of the levels of serum fasting blood glucose, insulin, IGF-1, AST, ATL, and CK-MB as compared with STZ-induced diabetic rats. CTS-SeNPs and Glib diminished the level of lipid peroxidation, increased total antioxidant capacity level, as well as possessed strong inhibition against serum α-amylase and α-glucosidase activities. Diabetic animals received CTS-SeNPs, or Glib demonstrated a significant (p < 0.05) decrease in the expression level of TCF7L2 and CAPN10 genes with a significant increase in the expression level of PPAR-γ gene, compared to STZ group. The above findings clarify the promising antidiabetic and antioxidant effect of CTS-SeNPs, recommending its inclusion in the currently used protocols for the treatment of diabetes and in the prevention of its related complications.

Nanoselenium improved learning, memory, and brain-derived neurotrophic factor and attenuated nitric oxide, and oxidative stress in the brain of juvenile hypothyroid rats

BACKGROUND

Nanoselenium (Nan S) is a form of selenium element that acts with high absorption and low toxicity. However, few studies have examined the effects of Nan S on cognitive impairment. On the other hand, hypothyroidism is a common disease that causes cognitive disorders. Therefore, this study aimed to investigate the effect of Nan S on memory impairment in rats due to propylthiouracil (PTU) - induced hypothyroidism. The roles of brain-derived neurotrophic factor (BDNF), nitric oxide (NO), and oxidative stress were also challenged.

MATERIALS AND METHODS

The animals were randomly divided into 4 groups: (1) Control group (normal saline), (2) hypothyroid (Hypo) group: where 0.05% PTU was added to drinking water, (3) and (4) Hypo-Nan S 50, Hypo-Nan S 100 in which 50 or 100 µg/ kg of Nan S were injected respectively. After 6 weeks, spatial and avoidance memory was measured by Morris water maze (MWM) and passive avoidance (PA) tests. The animals then underwent deep anesthesia and the serum samples and the hippocampus and cortex were collected to be used for thyroxin and biochemical measurements including malondialdehyde (MDA), NO, thiol, superoxide dismutase (SOD), catalase (CAT), and BDNF.

RESULTS

The rats showed an increase in the escape latency and traveled path in MWM in the Hypo group compare with the Control group and these parameters were decreased in both Hypo-Nan S 50 and Hypo-Nan S 100 groups compared to the Hypo group. The rats of both Hypo-Nan S 50 and Hypo-Nan S 100 groups spent longer time and traveled longer distances in the target area during the probe trial of MWM than the Hypo group. In addition, the latency to enter the dark box in the PA test was lower in the Hypo group than in the Control group, which was significantly improved after Nan S treatment. Furthermore, the hippocampal and cortical lipid peroxide marker (MDA) levels and NO metabolites of the Hypo group were significantly increased and the antioxidant markers (total thiol, SOD, and CAT) were significantly inhibited compared to the Control group. Compared with the Hypo group, Nan S administration could significantly decrease the oxidant factors and increase the activities antioxidant system and concentration of BDNF.

CONCLUSION

It is concluded that Nan S might be able to enhance endogenous antioxidant proteins due to its antioxidant activity, thereby improving BDNF and spatial and avoidance memory in the hypothyroidism-induced memory impairment model however, more studies are still necessary to elucidate the exact mechanism(s).

Protective effect of Allium atroviolaceum-synthesized SeNPs on aluminum-induced brain damage in mice

This study evaluated the possible neuroprotective effect of Allium atroviolaceum extract (AaE)-synthesized selenium nanoparticles (SeNPs) on aluminum (Al)-induced neurotoxicity in mice, explaining the likely mechanisms. Mice were divided into five groups: G1, control; G2, AaE group that received AaE (200 mg/kg) for 4 weeks; and groups 3, 4, and 5 received AlCl3 (100 mg/kg) for 3 weeks. After that, G4 received AaE (200 mg/kg), and G5 received SeNPs-AaE (0.5 mg/kg) for another 1 week. Exposure to AlCl3 boosted oxidative damage in brain tissue as evidenced by a reduction in glutathione concentrations and other antioxidant enzymes along with increased lipid peroxidation and nitric oxide levels. There was also a rise in the concentrations of interleukin-1β, TNF-α, and cyclooxygenase-II activities. AlCl3-treated mice showed reduced brain-derived neurotrophic factor (BDNF) and dopamine levels, increased acetylcholinesterase (AChE) activity, and reduced Bcl-2, and Bax, and caspase-3 activities. Treatment with SeNPs-AaE significantly reduced markers of oxidative stress, inflammation, and apoptosis. In addition, in SeNPs-AaE-treated rats, levels of BDNF and dopamine were significantly increased along with a reduction in AChE as compared with the AlCl3 group. Therefore, our results indicate that SeNPs-AaE has a potential neuroprotective effect against Al-mediated neurotoxic effects because of its powerful antioxidant, anti-inflammatory, anti-apoptotic, and neuromodulatory activities.

Pergularia tomentosa coupled with selenium nanoparticles salvaged lead acetate-induced redox imbalance, inflammation, apoptosis, and disruption of neurotransmission in rats’ brain

In this study, the neuroprotective potential of either Pergularia tomentosa leaf methanolic extract (PtE) alone or in combination with selenium nanoparticles (SeNPs-PtE) was investigated against lead acetate (PbAc)-induced neurotoxicity. Experimental rats were pretreated with PtE (100 mg/kg) or SeNPs-PtE (0.5 mg/kg) and injected intraperitoneally with PbAc (20 mg/kg) for 2 weeks. Notably, SeNPs-PtE decreased brain Pb accumulation and enhanced the level of dopamine and the activity of AChE compared to the control rats. In addition, elevated neural levels of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione along with decreased lipid peroxidation levels were noticed in pretreated groups with SeNPs-PtE. Moreover, SeNPs-PtE significantly suppressed neural inflammation, as indicated by lower levels of interleukin-1 beta, interleukin-6, tumor necrosis factor-alpha, nuclear factor-kappa B p65, and nitric oxide in the examined brain tissue. The molecular results also unveiled significant down-regulation in iNOS gene expression in the brains of SeNPs-PtE-treated rats. In addition, SeNPs-PtE administration counteracted the neural loss by increasing B-cell lymphoma 2 (Bcl-2) and brain-derived neurotrophic factor levels as well as decreasing BCL2-associated X protein and caspase-3 levels. To sum up, our data suggest that P. tomentosa extract alone or in combination with SeNPs has great potential in reversing the neural tissue impairment induced by PbAc via its antioxidant, anti-inflammatory, and anti-apoptotic activities. This study might have therapeutic implications in preventing and treating several lead-induced neurological disorders.

Exploring the Role of Lipid-Binding Proteins and Oxidative Stress in Neurodegenerative Disorders: A Focus on the Neuroprotective Effects of Nutraceutical Supplementation and Physical Exercise

The human brain is primarily composed of lipids, and their homeostasis is crucial to carry on normal neuronal functions. In order to provide an adequate amount of lipid transport in and out of the central nervous system, organisms need a set of proteins able to bind them. Therefore, alterations in the structure or function of lipid-binding proteins negatively affect brain homeostasis, as well as increase inflammation and oxidative stress with the consequent risk of neurodegeneration. In this regard, lifestyle changes seem to be protective against neurodegenerative processes. Nutraceutical supplementation with antioxidant molecules has proven to be useful in proving cognitive functions. Additionally, regular physical activity seems to protect neuronal vitality and increases antioxidant defenses. The aim of the present review was to investigate mechanisms that link lipid-binding protein dysfunction and oxidative stress to cognitive decline, also underlining the neuroprotective effects of diet and exercise.

Quercetin attenuates cyclophosphamide induced-immunosuppressive indoleamine 2,3-dioxygenase in the hippocampus and cerebral cortex of male Wister rats

This study investigated the protective effect of quercetin against cyclophosphamide-induced immunosuppressive indoleamine 2,3-dioxygenase (IDO) via the mechanism of oxidative-inflammatory stress and behavioral indices. Cyclophosphamide (CYP) was administered to male Wister rats at a dose of 100 mg/kg with or without quercetin 50 mg/kg every other day for 7 days. Experimental techniques including western blotting, immunohistochemistry analysis, and inflammatory and oxidative stress marker assays were carried out. We also conducted behavioral analyses such as open field, tail suspension, and Y-maze tests for cognitive assessment. The results indicated that quercetin attenuated oxidative-inflammatory stress induced by CYP in the hippocampus and cerebral cortex of male Wister rats by augmenting the activities of antioxidant enzymes and suppressing lipid peroxidation as well as inflammatory mediators such as interleukin-6 and interferon-γ. Concomitantly, quercetin partially prevented the alteration in brain tissue histological architecture and mitigated the activities of IDO/tryptophan 2,3-dioxygenase (TDO) and protein expression of IDO1. This was corroborated by the IDO-quercetin model obtained in silico, revealing a favorable inhibitory interaction between quercetin and the enzyme. Finally, the results of behavioral tests suggested that quercetin significantly prevented the depressive-like posture of the CYP-treated rats. Our study for the first time revealed that quercetin ameliorates the effect of CYP-instigated IDO/TDO activities in the cerebral cortex and hippocampus via restoration of antioxidant enzymes and preventing oxidative-inflammatory stress.

Toxicological effects of nanoselenium in animals

The productivity and sustainability of livestock production systems are heavily influenced by animal nutrition. To maintain homeostatic balance in the body of the animal at different phases of life, the percentage of organically active minerals in livestock feed must be optimized. Selenium (Se) is a crucial trace mineral that is required for the maintenance of many functions of the body. Se nanoparticles (SeNPs) attracted considerable interest from researchers for a variety of applications a decade ago, owing to their extraordinary properties. SeNPs offer significant advantages over larger-sized materials, by having a comparatively wider surface area, increased surface energy, and high volume. Despite its benefits, SeNP also has toxic effects, therefore safety concerns must be taken for a successful application. The toxicological effects of SeNPs in animals are characterized by weight loss, and increased mortality rate. A safe-by-strategy to certify animal, human and environmental safety will contribute to an early diagnosis of all risks associated with SeNPs. This review is aimed at describing the beneficial uses and potential toxicity of SeNPs in various animals. It will also serve as a summary of different levels of SeNPs which should be added in the feed of animals for better performance.

Targeting NRF2 in Type 2 diabetes mellitus and depression: Efficacy of natural and synthetic compounds

Evidence supports a strong bidirectional association between depression and Type 2 diabetes mellitus (T2DM). The harmful impact of oxidative stress and chronic inflammation on the development of both disorders is widely accepted. Nuclear factor erythroid 2-related factor 2 (NRF2) is a pertinent target in disease management owing to its reputation as the master regulator of antioxidant responses. NRF2 influences the expression of various cytoprotective phase 2 antioxidant genes, which is hampered in both depression and T2DM. Through interaction and crosstalk with several signaling pathways, NRF2 endeavors to contain the widespread oxidative damage and persistent inflammation involved in the pathophysiology of depression and T2DM. NRF2 promotes the neuroprotective and insulin-sensitizing properties of its upstream and downstream targets, thereby interrupting and preventing disease advancement. Standard antidepressant and antidiabetic drugs may be powerful against these disorders, but unfortunately, they come bearing distressing side effects. Therefore, exploiting the therapeutic potential of NRF2 activators presents an exciting opportunity to manage such bidirectional and comorbid conditions.

The mechanism of the neuroprotective effect of zinc against cadmium-induced behavioral impairments in male Wister rats: Focus on tryptophan degradation pathway, oxidative-inflammatory stress, and histologic evidence

The present study investigated the attenuating effects of Zn following Cd-exposure in the activities/expression of indoleamine 2, 3-dioxygenase (IDO), tryptophan 2, 3-dioxygenase (TDO), oxidative-inflammatory response, behavioral indices and histologic architecture in cerebral cortex and hippocampus of male rats. Adult male Wistar rats were exposed to 200μg/L and 100μg/L of Cd and/or Zn in drinking water for 42 days. Cd exposure significantly increased IDO and TDO activities, IDO 1 protein expression, inflammatory response, with attendant disruption in antioxidant systems and concomitant elevation in malondialdehyde (MDA) levels in the cerebral cortex and hippocampus. Following Zn co-treatment, Cd-mediated increase in IDO 1 protein expression, IDO, and TDO activities, and decrease in antioxidant enzymes, and an increase in markers of inflammatory response and MDA production were significantly (p < 0.05) reversed compared with control. Moreover, altered behavioral indices and histological architecture of brain sections following Cd exposure was evidently (p < 0.05) prevented by Zn co-treatment relative to control. Overall, Cd-induced alterations in IDO 1 expression, IDO and TDO activities, oxidative-inflammatory response, behavioral indices, and histological architecture in the cerebral cortex and hippocampus of rats within the time course of the investigation were prevented by Zn co-treatment.

Selenium Nanoparticles with Prodigiosin Rescue Hippocampal Damage Associated with Epileptic Seizures Induced by Pentylenetetrazole in Rats

BACKGROUND

Prodigiosin (PDG) is a red pigment synthesized by bacterial species with important pharmaceutical and biological activities. Here, we investigated the neuroprotective and anticonvulsant activities of green biosynthesized selenium formulations with PDG (SeNPs-PDG) versus pentylenetetrazole (PTZ)-induced epileptic seizures.

METHODS

Rats were assigned into six experimental groups: control; PTZ (60 mg/kg, epileptic model); sodium valproate (200 mg/kg) + PTZ; PDG (300 mg/kg) + PTZ; sodium selenite (0.5 mg/kg) + PTZ; and SeNPs-PDG (0.5 mg/kg) + PTZ. The treatment duration is extended to 28 days.

RESULTS

SeNPs-PDG pre-treatment delayed seizures onset and reduced duration upon PTZ injection. Additionally, SeNPs-PDG enhanced the antioxidant capacity of hippocampal tissue by activating the expression of nuclear factor erythroid 2-related factor 2 and innate antioxidants (glutathione and glutathione derivatives, in addition to superoxide dismutase and catalase) and decreasing the levels of pro-oxidants (lipoperoxidation products and nitric oxide). SeNPs-PDG administration inhibited inflammatory reactions associated with epileptic seizure development by suppressing the production and activity of glial fibrillary acidic protein and pro-inflammatory mediators, including interleukin-1 beta, tumor necrosis factor-alpha, cyclooxygenase-2, inducible nitric oxide synthase, and nuclear factor kappa B. Moreover, SeNPs-PDG protected against hippocampal cell loss following PTZ injection by decreasing the levels of cytosolic cytochrome c, Bax, and caspase-3 and enhancing the expression of anti-apoptotic Bcl-2. Interestingly, SeNPs-PDG restored the PTZ-induced imbalance between excitatory and inhibitory amino acids and improved monoaminergic and cholinergic transmission.

CONCLUSIONS

These promising antioxidative, anti-inflammatory, anti-apoptotic, and neuromodulatory activities indicate that SeNPs-PDG might serve as a naturally derived anticonvulsant agent.

Neuroprotective Efficiency of Prodigiosins Conjugated with Selenium Nanoparticles in Rats Exposed to Chronic Unpredictable Mild Stress is Mediated Through Antioxidative, Anti-Inflammatory, Anti-Apoptotic, and Neuromodulatory Activities

PURPOSE

Depression is a mood disorder accompanied by intensive molecular and neurochemical alterations. Currently, available antidepressant therapies are not fully effective and are often accompanied by several adverse impacts. Accordingly, the ultimate goal of this investigation was to clarify the possible antidepressant effects of prodigiosins (PDGs) loaded with selenium nanoparticles (PDGs-SeNPs) in chronic unpredictable mild stress (CUMS)-induced depression-like behavior in rats.

METHODS

Sixty Sprague Dawley rats were randomly allocated into six groups: control, CUMS group (depression model), fluoxetine (Flu, 10 mg/kg)+CUMS, PDGs+CUMS (300 mg/kg), sodium selenite (Na2SeO3, 400 mg/kg)+CUMS, and PDGs-SeNPs+CUMS (200 mg/kg). All treatments were applied orally for 28 consecutive days.

RESULTS

PDGs-SeNPs administration prevented oxidative insults in hippocampal tissue, as demonstrated by decreased oxidant levels (nitric oxide and malondialdehyde) and elevated innate antioxidants (glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase, and catalase), in addition to the upregulated expression of nuclear factor erythroid 2-related factor 2 and heme oxygenase-1 in rats exposed to CUMS. Additionally, PDGs-SeNPs administration suppressed neuroinflammation in hippocampal tissue, as determined by the decreased production of pro-inflammatory cytokines (tumor necrosis factor-alpha, interleukin-1β, and interleukin-6), increased anti-inflammatory cytokine interleukin-10, and decreased inflammatory mediators (prostaglandin E2, cyclooxygenase-2, and nuclear factor kappa B). Moreover, PDGs-SeNPs administration in stressed rats inhibited neuronal loss and the development of hippocampal apoptosis through enhanced levels of B cell lymphoma 2 and decreased levels of caspase 3 and Bcl-2-associated X protein. Interestingly, PDGs-SeNPs administration improved hormonal levels typically disrupted by CUMS exposure and significantly modulated hippocampal levels of monoamines, brain-derived neurotrophic factor, monoamine oxidase, and acetylcholinesterase activities, in addition to upregulating the immunoreactivity of glial fibrillary acidic protein in CUMS model rats.

CONCLUSION

PDGs-SeNPs may serve as a prospective antidepressant candidate due to their potent antioxidant, anti-inflammatory, and neuroprotective potential.

Cyclophosphamide instigated hepatic-renal oxidative/inflammatory stress aggravates immunosuppressive indoleamine 2,3-dioxygenase in male rats: Abatement by quercetin

The hepatic-renal toxicity associated with cyclophosphamide (CYP) treatment in both animals and humans have been reported. Quercetin, a dietary flavonoid, is known to elicit beneficial health effects. However, the influence of quercetin on the hepatic-renal toxicity associated with CYP-instigated indoleamine 2,3-dioxygenase is unavailable in the literature. The current study evaluated the effects of quercetin on the dysfunctional hepatic-renal status triggered by CYP exposure in rats. Experimental animals were exposed to CYP (100 mg/kg) or co-treated with quercetin (50 mg/kg) every other day for 7 days. Results revealed that quercetin treatment significantly assuaged CYP-mediated oxidative-inflammatory response, as well as augmenting serum levels of thyroid hormones. Additionally, quercetin attenuated CYP-induced reduction in antioxidant enzyme activities and enhanced hepatic-renal function markers, namely aspartate aminotransferase (AST), alanine aminotransferase (ALT), Alkaline phosphatase (ALP), and levels of urea and creatinine. Quercetin efficiently mitigated CYP-mediated increase in myeloperoxidase (MPO) activity, levels of nitric oxide and interleukin-6 (IL-6) in liver and kidney of rats. CYP-induced increase in the activities of immunosuppressive indoleamine 2, 3-dioxygenase (IDO) and tryptophan 2, 3-dioxygenase (TDO) in the tissues was abated in quercetin co-treated rats. In conclusion, Quercetin ameliorated deficits in the hepatic-renal function in CYP-exposed rats by lowering the activities/expression of immunosuppressive IDO and TDO via diminution of oxidative-inflammatory stress.

Therapeutic Potential and Main Methods of Obtaining Selenium Nanoparticles

This review presents the latest data on the importance of selenium nanoparticles in human health, their use in medicine, and the main known methods of their production by various methods. In recent years, a multifaceted study of nanoscale complexes in medicine, including selenium nanoparticles, has become very important in view of a number of positive features that make it possible to create new drugs based on them or significantly improve the properties of existing drugs. It is known that selenium is an essential trace element that is part of key antioxidant enzymes. In mammals, there are 25 selenoproteins, in which selenium is a key component of the active site. The important role of selenium in human health has been repeatedly proven by several hundred works in the past few decades; in recent years, the study of selenium nanocomplexes has become the focus of researchers. A large amount of accumulated data requires generalization and systematization in order to improve understanding of the key mechanisms and prospects for the use of selenium nanoparticles in medicine, which is the purpose of this review.

Effects of Sub-Lethal Doses of Selenium Nanoparticles on the Health Status of Rats

Selenium nanoparticles (SeNPs) are fast becoming a key instrument in several applications such as medicine or nutrition. Questions have been raised about the safety of their use. Male rats were fed for 28 days on a monodiet containing 0.5, 1.5, 3.0 and 5.0 mg Se/kg. Se content in blood and liver, liver panel tests, blood glucose, total antioxidant capacity (TAC), the activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx) were analysed. Liver and duodenum were subjected to histopathology examination. The weight gain of rats showed no differences between tested groups. Se content in blood was higher in all treated groups compared to the control group. The liver concentration of Se in the treated groups varied in the range from 222 to 238 ng/g. No differences were observed in the activity of AST (aspartate aminotransferase), ALP (alkaline phosphatase) and TAS (total antioxidant status). A significant decrease in ALT activity compared to the control group was observed in the treated groups. GPx activity varied from 80 to 88 U/mL through tested groups. SOD activity in liver was decreased in the SeNP-treated group with 5 mg Se/kg (929 ± 103 U/mL). Histopathological examination showed damage to the liver parenchyma and intestinal epithelium in a dose-dependent manner. This study suggests that short-term SeNP supplementation can be safe and beneficial in Se deficiency or specific treatment.