1-(Phenylselanyl)-2-(p-tolyl)indolizine: A selenoindolizine with potential antidepressant-like activity in mice mediated by the modulation of dopaminergic and noradrenergic systems.

1-(Phenylselanyl)-2-(p-tolyl)indolizine (MeSeI) is a selenoindolizine with an antidepressant-like effect in mice by regulation of the serotonergic system. This study investigated the involvement of dopaminergic and noradrenergic systems in the antidepressant-like action of MeSeI. For this purpose, Swiss male mice were pretreated with different antagonists, after 15 min, the MeSeI was administrated by intragastric (i.g.) via; after 30 min, the mouse behavior was assessed in the forced swimming test (FST). The action of MeSeI on the activity of monoamine oxidase (MAO) was determined. The pretreatment of mice with haloperidol (0.05 mg/kg, intraperitoneally, i.p.; non-selective dopamine receptor antagonist), sulpiride (50 mg/kg, i.p.; D2 receptor antagonist), yohimbine (1 mg/kg, i.p.; α2 receptor antagonist), and propranolol (2 mg/kg, i.p.; non-selective ß receptor antagonist), inhibited the anti-immobility action of MeSeI (50 mg/kg, i.g.) in the FST. This blocking effect was not observed when SCH23390 (0.01 mg/kg, i.p.; D1 receptor antagonist), and prazosin (1 mg/kg, i.p.; α1 receptor antagonist) were administered. The coadministration of subeffective doses of bupropion (3 mg/kg. i.g.; dopamine and noradrenaline reuptake inhibitor) and MeSeI (0.5 mg/kg. i.g.) reduced the immobility time in the FST. Furthermore, MeSeI inhibited MAO-A and B activities in vitro and ex vivo tests. These results suggest that MeSeI exerts its antidepressant-like effect via regulation of the D2, α2, and ß1 receptors and the inhibition of MAO-A and B activities. Molecular docking investigations corroborated these results. This study provides comprehensive insights into the antidepressant-like mechanism of MeSeI in mice, suggesting its potential as a novel antidepressant candidate.

Exploring the antioxidant potential of chalcogen-indolizines throughout in vitro assays.

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are highly reactive molecules produced naturally by the body and by external factors. When these species are generated in excessive amounts, they can lead to oxidative stress, which in turn can cause cellular and tissue damage. This damage is known to contribute to the aging process and is associated with age-related conditions, including cardiovascular and neurodegenerative diseases. In recent years, there has been an increased interest in the development of compounds with antioxidant potential to assist in the treatment of disorders related to oxidative stress. In this way, compounds containing sulfur (S) and/or selenium (Se) have been considered promising due to the relevant role of these elements in the biosynthesis of antioxidant enzymes and essential proteins with physiological functions. In this context, studies involving heterocyclic nuclei have significantly increased, notably highlighting the indolizine nucleus, given that compounds containing this nucleus have been demonstrating considerable pharmacological properties. Thus, the objective of this research was to evaluate the in vitro antioxidant activity of eight S- and Se-derivatives containing indolizine nucleus and different substituents. The in vitro assays 1,1-diphenyl-2-picryl-hydrazil (DPPH) scavenger activity, ferric ion (Fe3+) reducing antioxidant power (FRAP), thiobarbituric acid reactive species (TBARS), and protein carbonylation (PC) were used to access the antioxidant profile of the compounds. Our findings demonstrated that all the compounds showed FRAP activity and reduced the levels of TBARS and PC in mouse brains homogenates. Some compounds were also capable of acting as DPPH scavengers. In conclusion, the present study demonstrated that eight novel organochalcogen compounds exhibit antioxidant activity.

Green Synthesis of Molecules for the Treatment of Neglected Diseases.

Neglected tropical diseases (NTDs) affect mainly poor and marginalized populations of tropical and subtropical areas in 150 countries. Many of the chemical processes involved in the synthesis of active pharmaceutical ingredients (APIs) are highly polluting and inefficient, both in terms of materials and energy-consuming. In this review, we present the green protocols developed in the last 10 years to access new small molecules with potential applications in the treatment of leishmania, tuberculosis, malaria, and Chagas disease. The use of alternative and efficient energy sources, like microwaves and ultrasound, as well as reactions using green solvents and solvent-free protocols, are discussed in this review.

Involvement of the serotonergic system in the antidepressant-like effect of 1-(phenylselanyl)-2-(p-tolyl)indolizine in mice.

RATIONALE: Depression is a mental disorder that affects approximately 280 million people worldwide. In the search for new treatments for mood disorders, compounds containing selenium and indolizine derivatives show promising results. OBJECTIVES AND METHODS: To evaluate the antidepressant-like effect of 1-(phenylselanyl)-2-(p-tolyl)indolizine (MeSeI) (0.5-50 mg/kg, intragastric-i.g.) on the tail suspension test (TST) and the forced swim test (FST) in adult male Swiss mice and to elucidate the role of the serotonergic system in this effect through pharmacological and in silico approaches, as well to evaluate acute oral toxicity at a high dose (300 mg/kg). RESULTS: MeSeI administered 30 min before the FST and the TST reduced immobility time at doses from 1 mg/kg and at 50 mg/kg and increased the latency time for the first episode of immobility, demonstrating an antidepressant-like effect. In the open field test (OFT), MeSeI did not change the locomotor activity. The antidepressant-like effect of MeSeI (50 mg/kg, i.g.) was prevented by the pre-treatment with p-chlorophenylalanine (p-CPA), a selective tryptophan hydroxylase inhibitor (100 mg/kg, intraperitoneally-i.p. for 4 days), with ketanserin, a 5-HT2A/2C receptor antagonist (1 mg/kg, i.p.), and with GR113808, a 5-HT4 receptor antagonist (0.1 mg/kg, i.p.), but not with WAY100635, a selective 5-HT1A receptor antagonist (0.1 mg/kg, subcutaneous-s.c.) and ondansetron, a 5-HT3 receptor antagonist (1 mg/kg, i.p.). MeSeI showed a binding affinity with 5-HT2A, 5 -HT2C, and 5-HT4 receptors by molecular docking. MeSeI (300 mg/kg, i.g.) demonstrated low potential to cause acute toxicity in adult female Swiss mice. CONCLUSION: In summary, MeSeI exhibits an antidepressant-like effect mediated by the serotonergic system and could be considered for the development of new treatment strategies for depression.

Antidepressant-Like Effect of a Selenoindolizine in Mice: In Vivo and In Silico Evidence for the Involvement of the Serotonergic 5-HT2A/C Receptors.

The monoaminergic dysfunction plays a central role in major depressive disorder (MDD), a mental disturbance associated with constant feeling of sadness and lack of interest. The available treatments do not present a desirable efficacy and some of them provoke several adverse effects. In this context, organoselenium compounds and molecules containing the indolizine nucleus have demonstrated interesting pharmacological properties, including antidepressant-like effects. In this study, the antidepressant-like effect of 2-phenyl-1-(phenylselanyl)indolizine (SeI), a selenium-containing indolizine derivative, was investigated on the forced swimming test (FST) and on the tail suspension test (TST) in male Swiss mice. The involvement of the serotonergic system in this effect was also accessed. The selenium compound SeI (10-100 mg/kg, intragastrical (i.g.)) was administered 0.5 h before the behavioral tests, and it diminished the immobility on both FST and TST experiments, which is an indication of antidepressant-like effect. No changing in the locomotor motion was observed in the open-field test (OFT). The anti-immobility effect of SeI was not altered by the preadministration of the selective serotonergic receptor antagonists ondansetron (1 mg/kg, intraperitoneally (i.p.), antagonist of 5-HT3 receptor) and WAY100635 (0.1 mg/kg, subcutaneous route (s.c.), antagonist of 5-HT1A receptor). In contrast, the preadministration of ketanserin (1 mg/kg, i.p., antagonist of 5-HT2A/C receptor) blocked this effect, demonstrating that the antidepressant-like effect of SeI involves 5-HT2A/C. In addition, molecular docking studies showed a strong interaction between SeI and the receptors of 5-HT2A and 5-HT2C. The toxicological results demonstrated that SeI has low potential to cause adverse effects in mice. It was found that the antidepressant-like effect of SeI is related to modulation of the serotonergic system, and this selenium compound could be included in new treatment approaches for MDD.

"Green Is the Color": An Update on Ecofriendly Aspects of Organoselenium Chemistry.

Organoselenium compounds have been successfully applied in biological, medicinal and material sciences, as well as a powerful tool for modern organic synthesis, attracting the attention of the scientific community. This great success is mainly due to the breaking of paradigm demonstrated by innumerous works, that the selenium compounds were toxic and would have a potential impact on the environment. In this update review, we highlight the relevance of these compounds in several fields of research as well as the possibility to synthesize them through more environmentally sustainable methodologies, involving catalytic processes, flow chemistry, electrosynthesis, as well as by the use of alternative energy sources, including mechanochemical, photochemistry, sonochemical and microwave irradiation.

Selenium as a Versatile Reagent in Organic Synthesis: More than Allylic Oxidation.

For many years since its discovery, Selenium has played the role of a bad boy who became a hero in organic transformations. Selenium dioxide, for instance, is one of the most remembered reagents in allylic oxidations, having been applied in the synthesis of several naturally occurring products. The main goal of this review is to show the recent advances in the use of classical and new selenium reagents in organic synthesis. As demonstrated through the around 60 references discussed here, selenium can go even forward as a versatile reagent. We bring a collection of selenium reagents and their transformations that still asleep in the eyes of most synthetic organic chemists.

Selanylimidazopyridine abolishes inflammation- and stress-induced depressive-like behaviors by modulating the oxido-nitrosative system.

The 3-[(4-methoxyphenyl)selanyl]-2-phenylimidazo[1,2-a] pyridine (MPI), a novel organic selenium compound, has been receiving increased attention due to its antioxidant effects and its ability to protect against depression-like behaviours. However, it remains elusive whether MPI is able to reverse depressive-like symptoms and biochemical alterations in mice. In the present work, we explored the ability of MPI (10 mg/kg, i.g.) to reverse inflammation- and stress-induced depression-like behaviours in mice injected with tumour necrosis factor (TNF-α) or submitted to acute restraint stress. Depression-like behaviours were evaluated by the tail suspension and splash test and the open field test was used to evaluate the locomotor activity of mice. The prefrontal cortex and hippocampus of mice were used for the evaluation of parameters of oxidonitrosative stress. Here, we showed that a single administration of MPI abolished the depressive-like behaviours induced by TNF-α and acute restraint stress. The oxidative and nitrosative stress presented in mice with depression-like behaviours were also decreased by MPI in the prefrontal cortex and hippocampus. Our findings suggest that MPI presents antidepressant-like activity which is associated with the biochemical regulation of oxidative stress in prefrontal cortex and hippocampus of mice, arising as a promising strategy for the management of depressive symptoms.

Synthesis of 4-Arylselanyl-1H-1,2,3-triazoles from Selenium-Containing Carbinols.

In this work, we present a simple way to achieve 4-arylselanyl-1H-1,2,3-triazoles from selenium-containing carbinols in a one-pot strategy. The selenium-containing carbinols were used as starting materials to produce a range of selanyl-triazoles in moderate to good yields, including a quinoline and Zidovudine derivatives. One-pot protocols are crucial to the current concerns about waste production and solvent consumption, avoiding the isolation and purification steps of the reactive terminal selanylalkynes. We could also isolate an interesting and unprecedented by-product with one alkynylselenium moiety connected to the triazole.

Neuroprotective Effect of 3-[(4-Chlorophenyl)selanyl]-1-methyl-1H-indole on Hydrogen Peroxide-Induced Oxidative Stress in SH-SY5Y Cells.

Extensive data have reported the involvement of oxidative stress in the pathogenesis of neuropsychiatric disorders, prompting the pursuit of antioxidant molecules that could become adjuvant pharmacological agents for the management of oxidative stress-associated disorders. The 3-[(4-chlorophenyl)selanyl]-1-methyl-1H-indole (CMI) has been reported as an antioxidant and immunomodulatory compound that improves depression-like behavior and cognitive impairment in mice. However, the exact effect of CMI on specific brain cells is yet to be studied. In this context, the present study aimed to evaluate the antioxidant activity of CMI in H2O2-induced oxidative stress on human dopaminergic neuroblastoma cells (SH-SY5Y) and to shed some light into its possible mechanism of action. Our results demonstrated that the treatment of SH-SY5Y cells with 4 µM CMI protected them against H2O2 (343 µM)-induced oxidative stress. Specifically, CMI prevented the increased number of reactive oxygen species (ROS)-positive cells induced by H2O2 exposure. Furthermore, CMI treatment increased the levels of reduced glutathione in SH-SY5Y cells. Molecular docking studies demonstrated that CMI might interact with enzymes involved in glutathione metabolism (i.e., glutathione peroxidase and glutathione reductase) and H2O2 scavenging (i.e., catalase). In silico pharmacokinetics analysis predicted that CMI might be well absorbed, metabolized, and excreted, and able to cross the blood-brain barrier. Also, CMI was not considered toxic overall. Taken together, our results suggest that CMI protects dopaminergic neurons from H2O2-induced stress by lowering ROS levels and boosting the glutathione system. These results will facilitate the clinical application of CMI to treat nervous system diseases associated with oxidative stress.

Anhedonic- and anxiogenic-like behaviors and neurochemical alterations are abolished by a single administration of a selenium-containing compound in chronically stressed mice.

Despite the severity and the high prevalence of depression and anxiety and the efforts that have been done to improve their treatment, the available pharmacotherapy still has several limitations. Therefore, the investigation of novel agents and the characterization of the molecular signaling pathways underlying their effects are needed. The organoselenium compound 3-[(4-chlorophenyl)selanyl]-1-methyl-1H-indole (CMI) has emerged as a promising antidepressant and anxiolytic molecule in several animal models of depression through the modulation of neuroinflammation and oxidative stress. In light of this, the present study aimed to dive into the mechanism of action of CMI in ameliorating anhedonic- and anxiogenic-like behaviors induced by repeated corticosterone administration in mice. A single administration of CMI (1 â€‹mg/kg, i.g.) abrogated the behavioral alterations induced by corticosterone in the open field test, splash test, and elevated plus maze test. Additionally, CMI treatment decreased the levels of reactive species and lipid peroxidation in the plasma of corticosterone-treated mice and normalized the expression of GR, BDNF, synaptophysin, GSK-3ß, Nrf 2 , and IDO in the hippocampi of stressed mice. Noteworthy, the pre-treatment of mice with LY294002 (PI3K inhibitor) and rapamycin (mTOR inhibitor) abrogated the anti-anhedonic- and anxiolytic-like effects elicited by CMI in corticosterone-treated mice, while ZnPP (HO-1 inhibitor) counteracted the anxiolytic-like effect of CMI. These findings suggest that CMI might ameliorate behavioral and biochemical alterations in the depression-anxiety comorbidity induced by corticosterone, highlighting the potential of CMI as a possible adjuvant therapy.

Short- and Long-Term Repeated Forced Swim Stress Induce Depressive-Like Phenotype in Mice: Effectiveness of 3-[(4-Chlorophenyl)Selanyl]-1-Methyl-1H-Indole.

Exposure to stress highly correlates with the emergence of mood-related illnesses. Therefore, the present study was designed to characterize the acute and chronic effects of 3-((4-chlorophenyl)selanyl)-1-methyl-1H-indole (CMI) on depressive-like behavior induced by repeated forced swim stress (FSS) in male adult Swiss mice. In the repeated FSS, mice were placed in water to swim for a single trial during a 15-min period. Twenty-four hours after the first FSS, the animals were placed in water to swim through a series of four trials, and each of them swam for 6 min long; between each trial, mice were towel dried and returned to their home cage for 6 min. In addition, the oxidative stress in the prefrontal cortex and hippocampus and corticosterone levels of plasma of mice were investigated. The animals exposed to FSS were treated with CM in two different protocols. In protocol 1, CMI [1 and 10 mg/kg, intragastric (i.g.) route] or fluoxetine, a positive control (10 mg/kg, i.g. route), were administered 30 min before of sections of repeated FSS in both days of stress. After the last section of repeated FSS, the mice performed first the spontaneous locomotor activity and after the tail suspension test. In protocol 2, CMI or fluoxetine (1 mg/kg, i.g. route) was administered for 20 days after the exposition of repeated FSS. The spontaneous locomotor activity, tail suspension, and forced swimming tests were performed in this order after 24 h of last administration of CMI or fluoxetine. The euthanasia of animals was performed after the behavioral tests. CMI and fluoxetine abolished the depressive-like behavior induced by repeated FSS in mice in the two different treatments. CMI modulated the oxidative stress in the prefrontal cortices and hippocampi of mice subjected to repeated FSS. Mice subjected to repeated FSS had an increase in the corticosterone levels and CMI regulated the levels of this glucocorticoid. These findings demonstrate that CMI was effective to abolish the depressive-like behavior induced by repeated FSS, which was accompanied by changes in the corticosterone levels and oxidative stress of prefrontal cortices and hippocampi of mice.

3-[(4-chlorophenyl)selanyl]-1-methyl-1H-indole ameliorates long-lasting depression- and anxiogenic-like behaviors and cognitive impairment in post-septic mice: Involvement of neuroimmune and oxidative hallmarks.

Only in the last decade the long-term consequences of sepsis started to be studied and even less attention has been given to the treatment of psychological symptoms of sepsis survivors. It is estimated that 60% of sepsis survivors have psychological disturbances, including depression, anxiety, and cognitive impairment. Although the causative factors remain largely poorly understood, blood-brain barrier (BBB) disturbances, neuroinflammation, and oxidative stress have been investigated. Therefore, we sought to explore if the immunomodulatory and antioxidant selenocompound 3-[(4-chlorophenyl)selanyl]-1-methyl-1H-indole (CMI) would be able to ameliorate long-term behavioral and biochemical alterations in sepsis survivors male Swiss mice. CMI treatment (1 mg/kg, given orally for seven consecutive days) attenuated depression- and anxiogenic-like behaviors and cognitive impairment present one month after the induction of sepsis (lipopolysaccharide, 5 mg/kg intraperitoneally). Meantime, CMI treatment modulated the number of neutrophils and levels of reactive species in neutrophils, lymphocytes, and monocytes. In addition, peripheral markers of liver and kidneys dysfunction (AST, ALT, urea, and creatinine) were reduced after CMI treatment in post-septic mice. Notably, CMI treatment to non-septic mice did not alter AST, ALT, urea, and creatinine levels, indicating the absence of acute hepatotoxicity and nephrotoxicity following CMI treatment. Noteworthy, CMI ameliorated BBB dysfunction induced by sepsis, modulating the expression of inflammation-associated genes (NFκB, IL-1ß, TNF-α, IDO, COX-2, iNOS, and BDNF) and markers of oxidative stress (reactive species, nitric oxide, and lipid peroxidation levels) in the prefrontal cortices and hippocampi of mice. In conclusion, we unraveled crucial molecular pathways that are impaired in post-septic mice and we present CMI as a promising therapeutic candidate aimed to manage the long-lasting behavioral alterations of sepsis survivors to improve their quality of life.

Sweet Selenium: Synthesis and Properties of Selenium-Containing Sugars and Derivatives.

In the last decades, organoselenium compounds gained interest due to their important biological features. However, the lack of solubility, which characterizes most of them, makes their actual clinical exploitability a hard to reach goal. Selenosugars, with their intrinsic polarity, do not suffer from this issue and as a result, they can be conceived as a useful alternative. The aim of this review is to provide basic knowledge of the synthetic aspects of selenosugars, selenonium salts, selenoglycosides, and selenonucleotides. Their biological properties will be briefly detailed. Of course, it will not be a comprehensive dissertation but an analysis of what the authors think is the cream of the crop of this interesting research topic.

A Simple Zinc-Mediated Method for Selenium Addition to Michael Acceptors.

In this work, we focused our attention on seleno-Michael type reactions. These were performed using zinc-selenolates generated in situ from diphenyl diselenide 1, 1,2-bis(3-phenylpropyl)diselenide 30, and protected selenocystine 31 via an efficient biphasic Zn/HCl-based reducing system. Alkenes with a variety of electron-withdrawing groups were investigated in order to gauge the scope and limitations of the process. Results demonstrated that the addition to acyclic α,ß-unsaturated ketones, aldehydes, esters amides, and acids was effectively achieved and that alkyl substituents at the reactive ß-centre can be accommodated. Similarly, cyclic enones undergo efficient Se-addition and the corresponding adducts were isolated in moderate to good yield. Vinyl sulfones, α,ß-unsaturated nitriles, and chalcones are not compatible with these reaction conditions. A recycling experiment demonstrated that the unreacted Zn/HCl reducing system can be effectively reused for seven reaction cycles (91% conversion yield at the 7° recycling rounds).

The selenocompound 1-methyl-3-(phenylselanyl)-1H-indole attenuates depression-like behavior, oxidative stress, and neuroinflammation in streptozotocin-treated mice.

Major depressive disorder (MDD) is a chronic mental illness affecting a wide range of people worldwide. The pathophysiology of MDD is not completely elucidated, but it is believed that oxidative stress and neuroinflammation are involved. In light with this, the aim of the present study was to investigate whether a single administration of the antioxidant 1-methyl-3-(phenylselanyl)-1H-indole (MFSeI) was able to reverse the streptozotocin-induced depression-like behavior, oxidative stress, and neuroinflammation in mice. MFSeI (10 mg/kg) was administered intragastrically (i.g.) 24 h after the intracerebroventricular injection of STZ (0.2 mg/4 µL/per mouse). Thirty minutes after MFSeI administration, behavioral tests and neurochemical analyses were performed. Fluoxetine (10 mg/kg, i.g.) was used as a positive control. MFSeI and fluoxetine were able to reverse the STZ-induced depression-like behavior, as evidenced by decreased immobility time in the forced swimming test and increased grooming time in the splash test. Mechanistically, MFSeI reversed the increased levels of reactive species and lipid peroxidation in the prefrontal cortices and hippocampi of STZ-treated mice. Additionally, neuroinflammation (i.e. expression of NF-κB, IL-1ß, and TNF-α) and the reduced mRNA levels of BDNF in the and hippocampi of depressed mice were reversed by treatment with MFSeI. Fluoxetine did not improve the STZ-induced alterations at the levels of reactive species, NF-κB and BDNF in the prefrontal cortices neither the levels of TNF-α in both brain regions. Together, these data suggest that the MFSeI may be a promising compound with antidepressant-like action, reducing oxidative stress and modulating inflammatory pathways in the brain of depressed mice.

Toxicological evaluation of 3-(4-Chlorophenylselanyl)-1-methyl-1H-indole through the bovine oocyte in vitro maturation model.

The development of new bioactive molecules based on the molecular hybridization has been widely explored. In line with this, reliable tests should be employed to give information about the toxicology of these new molecules. In this sense, the use of in vitro tests is a valuable tool, especially the in vitro maturation of oocytes (IVM), which is an efficient resource to discover the potential toxicity of synthetic molecules. Thus, the aim of the present study was to evaluate the toxicological effects of the selenium-containing indolyl compound 3-(4-Chlorophenylselanyl)-1-methyl-1H-indole (CMI), on different quality parameters of bovine oocytes through the IVM. Different concentrations of the CMI compound (0, 25, 50, 100, 200 µM) were supplemented during the in vitro maturation process. After, the oocyte maturation rate, glutathione (GSH) levels, reactive oxygen species (ROS) levels, membrane, and mitochondrial integrity were evaluated. The results showed that the lowest concentration of CMI induced the highest GSH production (P < 0.05), an important marker of cytoplasmic quality and maturation. All treatments increased ROS production in relation to non-supplementation (P < 0.05). In addition, oocyte maturation was reduced only with the highest concentration of CMI (P < 0.05). Supplementation with CMI did not impact mitochondrial activity, integrity and cell membrane. To our knowledge, this is the first study that evaluates CMI on the oocyte in vitro maturation process. Importantly, our results did not find any toxic effect of CMI on bovine oocytes. CMI was efficient for cytoplasmic maturation by promoting an increase in the intracellular levels of glutathione.

Depression-like behavior, hyperglycemia, oxidative stress, and neuroinflammation presented in diabetic mice are reversed by the administration of 1-methyl-3-(phenylselanyl)-1H-indole.

Oxidative stress and neuroinflammation are found both in diabetes mellitus and major depressive disorder (MDD). In addition to damage in peripheral organs, such as liver and kidney, diabetic patients have a higher risk of developing depression. In this sense, the objective of the present study was to characterize the antidepressant-like effect of a selenium-containing compound, the 1-methyl-3-(phenylselanyl)-1H-indole (MFSeI), in streptozotocin (STZ)-induced diabetic mice. STZ (200 mg/kg, i.p.) was used to induce diabetes mellitus type I, and after seven days, the administration of MFSeI (10 mg/kg, i.g.) was initiated and followed for the next 14 days. Twenty-four hours after the last administration of MFSeI, the behavioral tests were performed, followed by euthanasia. The treatment with MFSeI was able to reverse the hyperglycemia induced by STZ. MFSeI also decreased the plasma levels of biomarkers of liver and kidney damage. Importantly, MFSeI reversed the depression-like behavior induced by STZ in the tail suspension test and forced swimming test without promoting locomotor alterations. Furthermore, MFSeI reversed the increased levels of reactive species and lipid peroxidation in the prefrontal cortex (PFC), hippocampus (HC), liver, and kidney of STZ-treated mice. Treatment with MFSeI also decreased the expression of tumor necrosis factor-alpha, inducible nitric oxide synthase and indoleamine 2,3-dioxygenase, while increasing the expression of interleukin-10, insulin receptor substrate-1 and glucose transport-4 in the PFC and HC of mice. Taken together, the results indicate the effectiveness of MFSeI against depression-like behavior and central and peripheral complications caused by diabetes in mice.

The antioxidant and immunomodulatory compound 3-[(4-chlorophenyl)selanyl]-1-methyl-1H-indole attenuates depression-like behavior and cognitive impairment developed in a mouse model of breast tumor.

Psychiatric alterations are often found in patients with breast cancer even before the initiation of adjuvant therapy, resulting in a poor quality of life. It has become accepted that neuroinflammation and oxidative stress are involved in the pathophysiology of depression and cognitive impairment. Herein, we tested the hypothesis that treatment with the antioxidant and immunomodulatory selenium-containing compound 3-[(4-chlorophenyl)selanyl]-1-methyl-1H-indole (CMI)could attenuate behavioral and neurochemical alterations in a mammary (4T1) tumor model. Female BALB/c mice were subcutaneously inoculated with 4T1 cancer cells (1 × 105 cells/mice) or PBS. From days 14 to 20, mice received daily gavage with canola oil or CMI. On day 21, mice were submitted to behavioral tests followed by euthanasia. We found that CMI did not alter tumor growth, body weight, and body temperature in tumor-bearing mice. Importantly, treatment with CMI abrogated tumor-induced depression-like behavior and cognitive impairment. By the time CMI improved the behavioral alterations, it had reduced tumor-induced neuroinflammation (altered expression of NFκB, IL-1ß, TNF-α, IL-10, IDO, and COX-2) and oxidative stress (altered expression of iNOS and Nrf2, and levels of reactive species, nitric oxide, lipid peroxidation, and superoxide dismutase activity) in the prefrontal cortices and hippocampi of mice. A molecular docking approach suggested the ability of CMI to inhibit the activity of iNOS and COX-2. Together, our results indicate that CMI treatment may attenuate depression and cognitive impairment in 4T1 tumor-bearing mice, and be a groundbreaking strategy for the treatment of cancer-related psychiatric symptoms to improve the quality of life of cancer patients.

Repeated administration of a selenium-containing indolyl compound attenuates behavioural alterations by streptozotocin through modulation of oxidative stress in mice.

Although the pathophysiology of major depression disorder (MDD) is still poorly understood, mounting evidence suggests that the brains of depressed patients are under oxidative stress, leading to depressive symptoms that may include anxiety and cognitive impairment. This study aimed to investigate if the seleno-organic compound 1-methyl-3-(phenylselanyl)-1H-indole (MFSeI) reverses the depression- and anxiogenic-like behaviour, cognitive impairment and oxidative stress induced by the intra-cerebroventricular injection of streptozotocin (STZ; 0.2 mg/4 µl/per mouse) in Swiss male mice. Twenty-four hours after the STZ injection, mice were treated with MFSeI (10 mg/kg, intra-gastrically), or vehicle solution, once daily for seven days. The behavioural tests were performed 30 min after the final MFSeI administration, followed by euthanasia and collection of the cerebral cortex and hippocampus. Administration of MFSeI reversed the depression- and anxiogenic-like behaviour and cognitive impairment induced by STZ, in mice. Neurochemical analyses demonstrated that MFSeI reversed the STZ-increased levels of reactive species, nitrite, lipid peroxidation and acetylcholinesterase activity in the cerebral cortex and hippocampus of mice. Moreover, a single administration of MFSeI (300 mg/kg, intra-gastrically) did not cause acute toxicity in Swiss male mice. Altogether, our data suggest that MFSeI exhibits antidepressant- and anxiolytic-like effects and improves the cognition of STZ-treated mice, without any toxicity.