Antioxidant and antidepressant-like activities of semi-synthetic α-phenylseleno citronellal

Organoselenium Compounds in Medicinal Chemistry

The chemical and biological interest in this element and the molecules bearing selenium has been exponentially growing over the years. Selenium, formerly designated as a toxin, becomes a vital trace element for life that appears as selenocysteine and its dimeric form, selenocystine, in the active sites of selenoproteins, which catalyze a wide variety of reactions, including the detoxification of reactive oxygen species and modulation of redox activities. From the point of view of drug developments, organoselenium drugs are isosteres of sulfur-containing and oxygen-containing drugs with the advantage that the presence of the selenium atom confers antioxidant properties and high lipophilicity, which would increase cell membrane permeation leading to better oral bioavailability. This statement is the paramount relevance considering the big number of clinically employed compounds bearing sulfur or oxygen atoms in their structures including nucleosides and carbohydrates. Thus, in this article we have focused on the relevant features of the application of selenium in medicinal chemistry. With the increasing interest in selenium chemistry, we have attempted to highlight the most significant published data on this subject, mainly concentrating the analysis on the last years. In consequence, the recent advances of relevant pharmacological organoselenium compounds are discussed.

Anticonvulsant effect of (±) citronellal possibly through the GABAergic and voltage-gated sodium channel receptor interaction pathways: In vivo and in silico studies

This study aimed to investigate the anticonvulsant effects of citronellal (CIT) and possible underlying mechanisms through an isoniazid (INH)-induced seizure (convulsion) via in vivo and in silico studies. For this, convulsions were induced by the oral administration of INH (300 mg/kg) to the mice. The animals were treated orally with different doses of CIT (50, 100, and 200 mg/kg). Vehicle served as a negative control (NC), while diazepam (DZP) (2 mg/kg) and carbamazepine (CAR) (80 mg/kg) were provided (p.o.) as positive controls (PC). A combination therapy of CIT (middle dose) with DZP and CAR was also given to two separate groups of animals to estimate the synergistic or antagonistic effects. Molecular docking and visualization of ligand-receptor interactions are also estimated through different computational tools. The results of the in vivo study showed that CIT dose-dependently significantly (p < 0.05) exhibited a higher onset of seizures while reducing the frequency and duration of seizures in mice compared to the NC group. Besides these, in combination therapy, CIT significantly antagonized the activity of CAR and DZP, leading to a reduction in the onset of seizures and an increase in their frequency and duration compared to treatment with CAR and DZP alone. Additionally, molecular docking revealed that the CIT exhibited a moderate binding affinity (-5.8 kcal/mol) towards the GABAA receptor and a relative binding affinity (-5.3 kcal/mol) towards the voltage-gated sodium channel receptor by forming several bonds. In conclusion, CIT showed moderate anticonvulsant activity in INH-induced convulsion animals, possibly by enhancing GABAA receptor activity and inhibiting the voltage-gated sodium channel receptor.

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.

Citronellal as a Promising Candidate for Alzheimer's Disease Treatment: A Comprehensive Study on In Silico and In Vivo Anti-Acetylcholine Esterase Activity

One of the primary therapeutic approaches for managing Alzheimer's disease (AD) involves the modulation of Acetylcholine esterase (AChE) activity to elevate acetylcholine (ACh) levels inside the brain. The current study employed computational chemistry approaches to evaluate the inhibitory effects of CTN on AChE. The docking results showed that Citronellal (CTN) and standard Donepezil (DON) have a binding affinity of -6.5 and -9.2 Kcal/mol, respectively, towards AChE. Further studies using molecular dynamics (MD) simulations were carried out on these two compounds. Binding free energy calculations and ligand-protein binding patterns suggested that CTN has a binding affinity of -12.2078. In contrast, DON has a much stronger binding relationship of -47.9969, indicating that the standard DON has a much higher binding affinity than CTN for AChE. In an in vivo study, Alzheimer-type dementia was induced in mice by scopolamine (1.5 mg/kg/day i.p) for 14 days. CTN was administered (25 and 50 mg/kg. i.p) along with scopolamine (SCO) administration. DON (0.5 mg/kg orally) was used as a reference drug. CTN administration significantly improved the mice's behavior as evaluated by the Morris water maze test, evident from decreased escape latency to 65.4%, and in the CPS test, apparent from reduced escape latency to 69.8% compared to the positive control mice. Moreover, CTN significantly increased the activities of antioxidant enzymes such as catalase and superoxide dismutase (SOD) compared to SCO. Furthermore, CTN administration significantly decreased SCO-induced elevated AChE levels in mice. These results were supported by histopathological and in silico molecular docking studies. CTN may be a potential antioxidant and neuroprotective supplement.

Genotoxicity assessment of 1,4-anhydro-4-seleno-D-talitol (SeTal) in human liver HepG2 and HepaRG cells

1,4-Anhydro-4-seleno-D-talitol (SeTal) is a highly water-soluble selenosugar with interesting antioxidant and skin-tissue-repair properties; it is highly stable in simulated gastric and gastrointestinal fluids and is a potential pharmaceutical ingredient that may be administered orally. Hepatic toxicity is often a major problem with novel drugs and can result in drug withdrawal from the market. Predicting hepatotoxicity is therefore essential to minimize late failure in the drug-discovery process. Herein, we report in vitro studies to evaluate the cytotoxic and genotoxic potential of SeTal in HepG2 and hepatocyte-like differentiated HepaRG cells. Except for extremely high concentrations (10 mM, 68 h-treatment in HepG2), SeTal did not affect the viability of each cell type. While the highest examined concentrations (0.75 and 1 mM in HepG2; 1 mM in HepaRG) were observed to induce primary DNA damage, SeTal did not exhibit clastogenic or aneugenic activity toward either HepG2 or HepaRG cells. Moreover, no significant cytostasis variations were observed in any experiment. The clearly negative results observed in the CBMN test suggest that SeTal might be used as a potential active pharmaceutical ingredient. The present study will be useful for the selection of non-toxic concentrations of SeTal in future investigations.

Effect of Rosa damascena Extract on Rat Model Alzheimer's Disease: A Histopathological, Behavioral, Enzyme Activities, and Oxidative Stress Study

The purpose of the current study is to investigate the effect of aquatic Rosa damascena extract against the oxidative damage induced by aluminum chloride intoxication in Alzheimer's model of Wister rats. Rats were divided randomly into seven groups (n = 10). Control group received no treatment, sham group received distilled water orally, aluminum group (AL) was administered AlCl3 (100 mg/kg) orally, extract 1 and 2 groups were treated with only aqueous R. damascena extract (DRE) (500 and 1000 mg/kg), and treatment 1 and 2 groups received aqueous R. damascena extract (500 and 1000 mg/kg) and AlCl3 (100 mg/kg) orally. The brain tissues were sampled for histopathological examination, and biochemical analysis was conducted for estimating the enzyme activities of acetylcholinesterase and catalase (CAT), the levels of GSH and MDA, and ferric reducing antioxidant power. According to the results of behavioral tests, AL administration showed a reduction in spatial memory and remarkably increased the time needed for reaching the invisible platform. The administration of Al-induced oxidative stress and an increase of the enzyme activity of AChE. Al administration increased AChE level from 1.176 ± 0.173 to 3.62 ± 0.348, which was a significant rise. However, treating with the extract at the dose of 1000 mg/kg downregulated it to 1.56 ± 0.303. Administration of the R. damascene extract caused an increased level of catalase and glutathione levels in treatment groups, attenuated MDA level, and regulated AChE activity. Our results illustrate that administration of R. damascene extract has a protective effect against the oxidative damage induced by AlCl3 intoxication in Alzheimer's model.

Antidepressant Effects of South African Plants: An Appraisal of Ethnobotanical Surveys, Ethnopharmacological and Phytochemical Studies

Globally, the search for safe and potent natural-based treatment for depression is receiving renewed interest given the numerous side-effects associated with many existing drugs. In South Africa, the use of plants to manage depression and related symptoms is fairly documented among different ethnic groups. In the current study, we reviewed existing ethnobotanical, ethnopharmacological and phytochemical studies on South African medicinal plants used to manage depression. Electronic databases were accessed for scientific literature that meets the inclusion criteria. Plants with ethnobotanical evidence were subjected to a further pharmacological review to establish the extent (if any) of their effectiveness as antidepressants. Critical assessment resulted in 20 eligible ethnobotanical records, which generated an inventory of 186 plants from 63 plant families. Due to the cultural differences observed in the definition of depression, or lack of definition in some cultures, most plants are reported to treat a wide range of atypical symptoms related to depression. Boophone disticha, Leonotis leonurus and Mentha longifolia were identified as the three most popular plants, with over eight mentions each from the ethnobotanical records. The dominant families were Asteraceae (24), Fabaceae (16), Amaryllidaceae (10), and Apocynaceae (10) which accounted for about 32% of the 186 plants. Only 27 (≈14.5%) of the plants have been screened for antidepressant activity using in vitro and in vivo models. Agapanthus campanulatus, Boophone disticha, Hypericum perforatum, Mondia whitei and Xysmalobium undulatum, represent the most studied plants. Phytochemical investigation on nine out of the 27 plants revealed 24 compounds with antidepressant-like effects. Some of these included buphanidrine and buphanamine which were isolated from the leaves of Boophone disticha, Δ⁹-tetrahydrocannabinol, cannabidiol and cannabichromene obtained from the buds of Cannabis sativa and carnosic acid, rosmarinic acid and salvigenin from Rosmarinus officinalis, A significant portion (≈85%) of 186 plants with ethnobotanical records still require pharmacological studies to assess their potential antidepressant-like effects. This review remains a valuable reference material that may guide future ethnobotanical surveys to ensure their robustness and validity as well as database to identify promising plants to screen for pharmacology efficacy.

Pterostilbene-isothiocyanate inhibits breast cancer metastasis by selectively blocking IKK-β/NEMO interaction in cancer cells

Metastasis, the main cause of breast cancer-associated fatalities, relies on many regular pathways involved in normal cell physiology and metabolism, thus, making it challenging to identify disease-specific therapeutic target(s). Chemically synthesized anti-metastatic agents are preferred for their fast and robust actions. However, these agents have adverse side effects, thus, increasingly favouring the identification of phytocompounds as suitable alternatives. Resveratrol and pterostilbene have long been established as potent anti-cancer agents. Earlier studies from our laboratory documented the anti-cancer activities associated with pterostilbene-isothiocyanate (PTER-ITC), a derivative of pterostilbene. The current study focuses on evaluating the anti-metastatic property of PTER-ITC and the underlying mechanism, by employing in silico, in vitro, and in vivo approaches. The significant anti-metastatic activity of PTER-ITC was observed in vitro against breast cancer metastatic cell line (MDA-MB-231) and in vivo in the 4T1 cell-induced metastatic mice model. Epithelial-mesenchymal transition (EMT), a hallmark of metastasis regulated by the transcription factors, Snail1 and Twist, was found to be reverted in vitro by PTER-ITC treatment. PTER-ITC blocked the activation of NF-κB/p65 and its concomitant nuclear translocation, resulting in the transcriptional repression of its target genes, Snail1 and Twist. PTER-ITC prevented the formation of IKK complex, central to NF-κB activation, by binding to the NEMO-binding domain (NBD) of IKK-β and inhibiting its interaction with NEMO (NF-κB essential modulator). According to our observations, PTER-ITC attenuated NF-κB activation selectively in cancerous cells. In conclusion, this study demonstrated that PTER-ITC is a potent anti-metastatic agent capable of targeting physiologically important pathways in a cancer-specific manner.

Three -(pyridin-2-yl)-2-(pyridin-2-ylimino)thiazolidin-4-one as a novel inhibitor of cerebral MAO-B activity with antioxidant properties and low toxicity potential

Some brain diseases are associated with oxidative stress and altered monoamine oxidase (MAO) activity. The objective of this study was to evaluate the antioxidant and neuroprotective actions through MAO inhibition of 3-(pyridin-2-yl)-2-(pyridine-2-ylimino) thiazolidin-4-one (PPIT, a synthetic molecule containing a thiazolidinone nucleus), as well as its effects on toxicity parameters in Swiss female mice. Five in vitro assays were carried out to verify the PPIT antioxidant capacity: protein carbonylation (PC), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 1,1-diphenyl-2-picryl-hydrazil (DPPH), ferric ion (Fe³⁺ ) reducing antioxidant power (FRAP), and superoxide dismutase (SOD)-like activity. The results showed that PPIT reduced the level of PC in the homogenate of the brain. This compound did not demonstrate SOD mimetic activity, but it acted as a free radical scavenger (ABTS and DPPH) and exhibited reducing activity in the FRAP assay. In addition, the effects of PPIT on cerebral MAO activity (MAO-A and B isoforms) were investigated in vitro. Our data revealed inhibition of the MAO-B activity by PPIT with no effects on MAO-A. Lastly, an acute oral toxicity test was conducted in mice. No changes in food intake, body weight, and biochemical markers of kidney and liver damage were detected in mice treated with a high dose of PPIT (300 mg/kg). In conclusion, the present study demonstrated that PPIT exhibits antioxidant activity and selectively inhibits the MAO-B isoform without causing apparent toxicity. These findings suggest PPIT as a potential therapeutic candidate to be tested in preclinical models of brain diseases involving perturbations of MAO-B activity and redox status.

Toxicology and pharmacology of synthetic organoselenium compounds: an update

Here, we addressed the pharmacology and toxicology of synthetic organoselenium compounds and some naturally occurring organoselenium amino acids. The use of selenium as a tool in organic synthesis and as a pharmacological agent goes back to the middle of the nineteenth and the beginning of the twentieth centuries. The rediscovery of ebselen and its investigation in clinical trials have motivated the search for new organoselenium molecules with pharmacological properties. Although ebselen and diselenides have some overlapping pharmacological properties, their molecular targets are not identical. However, they have similar anti-inflammatory and antioxidant activities, possibly, via activation of transcription factors, regulating the expression of antioxidant genes. In short, our knowledge about the pharmacological properties of simple organoselenium compounds is still elusive. However, contrary to our early expectations that they could imitate selenoproteins, organoselenium compounds seem to have non-specific modulatory activation of antioxidant pathways and specific inhibitory effects in some thiol-containing proteins. The thiol-oxidizing properties of organoselenium compounds are considered the molecular basis of their chronic toxicity; however, the acute use of organoselenium compounds as inhibitors of specific thiol-containing enzymes can be of therapeutic significance. In summary, the outcomes of the clinical trials of ebselen as a mimetic of lithium or as an inhibitor of SARS-CoV-2 proteases will be important to the field of organoselenium synthesis. The development of computational techniques that could predict rational modifications in the structure of organoselenium compounds to increase their specificity is required to construct a library of thiol-modifying agents with selectivity toward specific target proteins.

Arylseleninic acid as a green, bench-stable selenylating agent: synthesis of selanylanilines and 3-selanylindoles

C–Se bonds in electron-rich arenes are easily formed by the reaction of bench-stable arylseleninic acids as an electrophilic selenium source. The only waste in the reaction is water.

Microwave-Assisted Extraction Combined with In-Capillary [Fe(ferrozine)3]2+-CE-DAD to Screen Active Components with the Ability to Chelate Ferrous Ions from Flos Sophorae Immaturus (Flos Sophorae)

An efficient microwave-assisted extraction (MAE) combined with in-capillary [Fe(ferrozine)3]2+-capillary electrophoresis-Diode Array Detector (in-capillary [Fe(ferrozine)3]2+-CE-DAD) was developed to screen active components with the ability to chelate ferrous ions and determine the total antioxidant activity. The MAE conditions, including methanol concentration, extraction power, extraction time, and the ratio of material to liquid, were optimized by an L₉(3⁴) orthogonal experiment. Background buffer, voltage, and cartridge temperature that affect the separation of six compounds were optimized. It was found that rutin and quercetin were the main components chelating ferrous ions in Flos Sophorae Immaturus (Flos Sophorae) by the in-capillary [Fe(ferrozine)₃]²⁺-CE-DAD. The recoveries were ranged from 95.2% to 104%. It was concluded that the MAE combined with in-capillary [Fe(ferrozine)₃]²⁺-CE-DAD method was a simple, reliable, and efficient tool for screening active components from the complex traditional Chinese medicine samples and evaluating their ability to chelate ferrous ions.

A novel methodology for the synthesis of condensed selenium heterocycles based on the annulation and annulation–methoxylation reactions of selenium dihalides

A novel methodology for accelerating the annulation was developed based on the reactions of selenium dihalides in the presence of alcohols.

Maternal restraint stress during pregnancy negatively affects behaviors and antioxidant capacity of offspring rats (Rattus norvegicus)

This study evaluated the effect of maternal restraint stress during the gestation period on behaviors, biochemical parameters, and antioxidant capacities of offspring rats (Rattus norvegicus (Berkenhout,1769)) at weaning age. Behaviors, plasma biochemical indices, and antioxidant ability of the liver, soleus muscle, and gastrocnemius muscle of mother and (or) offspring rats were analyzed. Significant increases were found in the immobility and swinging behavior frequencies of offspring male rats; no difference was found in behaviors of female rats. The antioxidant indices including superoxide dismutase, nitric oxide synthase, and total antioxidant capacity in the soleus muscle of offspring male rats were significantly decreased in the restraint group. Female offspring rats showed significant lower glutathione and higher malondialdehyde levels in the gastrocnemius muscle and liver, respectively. No difference was found in the productive performance and plasma biochemical indices of maternal rats, nor in the biochemical parameters of the two groups of weaning rats. The results suggested that maternal chronic stresses negatively affected the behaviors and antioxidant abilities of offspring rats, and that these effects possibly have a greater impact on offspring male rats than on female rats.

Therapeutic applications of selenium-derived compounds

Selenium is a biocompatible element and participates in several biochemical reactions occurring in the human body. Its biocompatibility and minimal toxicity has attracted researchers to develop selenium-based drugs. Hence, recent developments on biomedical applications of selenium-based compounds have been discussed. A structure activity relationship has also been interpreted.

Computational and biological evidences on the serotonergic involvement of SeTACN antidepressant-like effect in mice

A series of phenylselanyl-1H-1,2,3-triazole-4-carbonitriles with different substituents were screened for their binding affinity with serotonin transporter (SERT) and dopamine transporter (DAT) by docking molecular. 5-(4methoxyphenyl)-1-(2-(phenylselanyl)phenyl)-1H-1,2,3-triazole-4-carbonitrile (SeTACN) exhibited the best conformation with SERT even higher than fluoxetine and serotonin, suggesting a competitive inhibition. SeTACN demonstrated additional affinity to other serotonergic receptors involved in antidepressant effects: 5HT_1a, 5HT_2a and 5HT₃. In another set of experiments, SeTACN led to significant reductions in the immobility time of mice submitted to forced swimming test (FST) in the dose range of 0.1- 20mg/kg, suggesting an antidepressant-like effect. The possible mechanism of action was investigated using serotonergic and dopaminergic antagonists. The antidepressant-like effect of SeTACN (0.1mg/kg i.g.) was prevented by the pretreatment with WAY100635 (a selective 5HT_1a antagonist), ketanserin (a 5HT2_a/c antagonist) and ondansetron (a selective 5ht₃ antagonist), PCPA (an inhibitor of serotonin synthesis) but not with SCH23390 (dopaminergic D₁ antagonist) and sulpiride (D₂ antagonist). Sub-effective dose of fluoxetine was able to potentiate the effects of a sub-effective dose of SeTACN in FST. None of the treatments affected locomotor activity in open field test (OFT). These results together, suggest that the SeTACN antidepressant-like effect is mediate, at least in parts, by serotonergic system.

Ultrasound-promoted copper-catalyzed synthesis of bis-arylselanyl chrysin derivatives with boosted antioxidant and anticancer activities

Herein we report the use of ultrasonic irradiation (US) in the synthesis of six new semi-synthetic selenium-containing chrysin derivatives by a simple and effective methodology utilizing CuI as catalyst, in good to excellent yields (60-89%). It was observed that US accelerates the reaction compared to conventional heating with excellent selectivity for diselenylated products. Compounds were tested for their antioxidant and anticancer activities in vitro and it was observed that the presence of selenium in the A-ring of chrysin enhanced both antioxidant and anticancer properties. Semi-synthetic 6,8-bis(o-tolylselanyl)-chrysin 3b has the best radical scavenging activity of DPPH (I_max: 39.79µM) and ABTS⁺ (IC₅₀: 6.5µM) radicals. Similarly, in the Reactive Species (RS) assay, 3b showed high antioxidant activity in mice cortex (IC₅₀: 5.67µM), whereas 6,8-bis(p-anisoylselanyl)-chrysin 3c was the more active in the hippocampus (IC₅₀: 5.63µM). The Se-chrysins were effective in prevention of lipid peroxidation, highlighting 6,8-bis(p-fluorophenylselanyl)-chrysin 3d in cortex (IC₅₀: 0.54µM) and 3b in hippocampus (IC₅₀: 0.27µM). In addition, 3d was effective in inhibiting human lung adenocarcinoma (A549) cells growth, with a IC₅₀ of 19.9µM after 72h of treatment, while 6,8-bis(p-anisoylselanyl)-chrysin 3c presented the higher antiproliferative activity after 48h of treatment (IC₅₀ of 41.4µM).

Selenium and manganese in depression – preclinical and clinical studies

According to the World Health Organization estimates, approximately 10% of the world’s population is affected by depressive disorders. Furthermore, even in high-income countries, many people with depression are not treated, which can lead to serious health consequences and a global economic loss. Unfortunately, the current pharmacotherapy of depressive disorders is characterized by unsatisfactory efficacy and the therapeutic effect is accompanied by many side effects. For this reason, there is still ongoing worldwide research to find new antidepressant therapies. In recent years, many data have been shown that essential elements demonstrate the antidepressant action and increase the effect of antidepressants. In this paper we present the results from the preclinical and clinical studies published over the years which show the involvement of selenium and manganese in depressive disorders. In this article, the relationship between the amount of these microelements in a diet and depression is reviewed and what's more, the association among these elements in different biomaterial and their relations to depressive symptoms is presented. Additionally, we discuss the possible influence of selenium and manganese on modulating neurotransmitter system involved in depression.

Monoterpenes as a renewable source of biologically active compounds

Monoterpenes and their derivatives play an important role in the creation of new biologically active compounds including drugs. The review focuses on the data on various types of biological activity exhibited by monoterpenes and their derivatives, including analgesic, anti-inflammatory, anticonvulsant, antidepressant, anti-Alzheimer, anti-Parkinsonian, antiviral, and antibacterial (anti-tuberculosis) effects. Searching for novel potential drugs among monoterpene derivatives shows great promise for treating various pathologies. Special attention is paid to the effect of absolute configuration of monoterpenes and monoterpenoids on their activity.

Promising link between selenium and peroxisome proliferator activated receptor gamma in the treatment protocols of obesity as well as depression

Considerable interest has been given to the significance of peroxisome proliferator activated receptors (PPARs) in macronutrient metabolism, however, there is not sufficient data concerning the interactions between PPARs and micronutrients. Investigations performed on PPARγ and one of the essential micronutrients selenium (Se) have shown that both parameters may lead to alterations in obesity-related or mood disorders. Therefore, it is plausible to consider PPARγ and Se together as a powerful combination during the treatment of two associated diseases; obesity and depression. PPARγ has been shown to be involved in the antidepressant-like activity. It is also an important parameter to be considered in obesity as the master regulator of adipogenesis. The mechanism of action of PPARγ is initiated by ligand binding which induces a conformational change in the receptor. Se is capable of alleviating inflammatory signaling pathways. Obesity is associated with chronic low-grade inflammation. Depression is also defined as an inflammatory disorder. Inflammatory mediators such as tumor necrosis factor-alpha (TNFα) participate in the progression of depression. They are also obesity-associated parameters. Due to TNFα induced depressive-like behaviors and the positive association between this proinflammatory cytokine and obesity, TNFα-activated signaling pathways and those inhibiting them have recently gained importance as potential targets and therapeutic tools, respectively. More studies are necessary to develop compounds with therapeutic nature against depressive disorders and obesity. PPARγ is an important signaling pathway that occurs at the crossroads of depression and obesity. Se, aside from its anti-inflammatory, anticarcinogenic and antioxidative nature, affects also the way of PPARγ action. Se supplementation or fortification as well as the development of the partial agonists of PPARγ in which lipophilic Se compounds are used as ligand followed by experimental trials and human studies using the newly developed compounds will be promising approaches for future hope during the treatment of these diseases.

Involvement of monoaminergic system in the antidepressant-like effect of (octylseleno)-xylofuranoside in the mouse tail suspension test

Depression is one of the most commonly diagnosed neuropsychiatric disorders and several studies have demonstrated a role for selenium in mood disorders. For this reason, the present study investigated the role of the monoaminergic system in the antidepressant-like action of (octylseleno)-xylofuranoside (OSX), an organoselenium compound, in the tail suspension test (TST) in mice. For this purpose, OSX (0.001–10 mg/kg) was administered orally (p.o.) 30 min prior to testing, and all of the tested doses reduced the immobility time in the TST without changing the locomotor activity measured in the open field test (OFT). Furthermore, the antidepressant-like effect of OSX (0.01 mg/kg, p.o.) in the TSTwas prevented by pre-treatment in mice with ketanserin (1 mg/kg, intraperitoneal route (i.p.); a 5-HT2A/2C receptor antagonist),WAY100635 (0.1mg/kg, subcutaneous (s.c.); a selective 5-HT1A receptor antagonist), p-chlorophenylalaninemethyl ester-PCPA (100mg/kg, i.p.; a selective inhibitor of tryptophan hydroxylase), prazosin (1 mg/kg, i.p.; an α1-adrenoceptor antagonist), yohimbine (1 mg/kg, i.p.; an α2-adrenoceptor antagonist), SCH233390 (0.05 mg/kg, s.c., a dopaminergic D1 receptor antagonist) and sulpiride (50 mg/kg, i.p., a dopaminergic D2 receptor antagonist), but not with ondansetron (1 mg/kg, i.p.; a selective 5-HT3 receptor antagonist). Taken together, these data demonstrate that OSX has a potent antidepressant like effect in TST at lower doses (0.001–10 mg/kg), which is dependent on its interaction with the serotonergic, noradrenergic and dopaminergic systems.

Polyethylene glycol-400/H3PO2: an eco-friendly reductive system for the synthesis of selanylesters

An alternative green method was described for the synthesis of selanylesters by reactions of acyl chlorides with arylselenols, generated in situ by reaction of diaryl diselenides with hypophosphorous acid (H₃PO₂) using polyethylene glycol-400 (PEG-400) as the solvent.