Time-dependent dual mode of action of COX-2 inhibition on mouse serum corticosterone levels.

To elucidate the effect of cyclooxygenase-2 (COX-2) inhibition on corticosterone release, mice were divided into a group receiving NS398, a selective COX-2 inhibitor at a dose of 3 mg/kg for seven days, and a group receiving NS398 for fourteen days. After this time, the mice were sacrificed, and blood serum was collected. An ELISA protocol was used to analyze serum corticosterone levels. Short-term COX-2 inhibition increased corticosterone levels, while long-term inhibition lowered them. The exact schedule of experiments was repeated after the lipopolysaccharide (LPS) Escherichia coli challenge in mice to check the influence of stress stimuli on the tested parameters. In this case, we observed increases in corticosterone levels, significant in a seven-day pattern. These results indicate that corticosterone levels are regulated through a COX-2-dependent mechanism in mice.

Cyclooxygenase-2 inhibition affects the ratio of GluN2A/GluN2B receptor subunits through interaction with mGluR5 in the mouse brain.

N-methyl-D-aspartic acid receptors (NMDARs) are the most studied receptors in mammalian brains. Their role in depression, cognition, schizophrenia, learning and memorization, Alzheimer's disease, and more is well documented. In the search for new drug candidates in depression, intensive studies have been conducted. Compounds that act by influencing NMDARs have been particularly intensively investigated following the success of ketamine in clinics. Unfortunately, the side effects associated with ketamine do not allow it to be useful in all cases. Therefore, it is important to learn about new unknown mechanisms related to NMDAR activation and study the impact of changes in the excitatory synapse environment on this receptor. Both direct and intermediary influence on NMDARs via mGluRs and COX-2 are effective. Our prior studies showed that both mGluRs ligands and COX-2 inhibitors are potent in depression-like and cognitive studies through mutual interactions. The side effects associated with imipramine administration, e.g., memory impairment, were improved when inhibiting COX-2. Therefore, this study is a trial that involves searching for modifications in NMDARs in mouse brains after prolonged treatment with MTEP (mGluR5 antagonist), NS398 (COX-2 inhibitor), or imipramine (tricyclic antidepressant). The prefrontal cortex (PFC) and hippocampus (HC) were selected for PCR and Western blot analyses. Altered expression of Gin2a or Grin2b genes after treatment was found. The observed effects were more potent when COX-2 was inhibited. The finding described here may be vital when searching for new drugs acting via NMDARs without the side effects related to cognition.

Secondary hyperparathyroidism in chronic kidney disease: pathomechanism and current treatment possibilities.

Secondary hyperparathyroidism (SHPT) is one of the most common metabolic complications resulting from chronic kidney disease (CKD). The complexity of calcium and phosphate disorders associated with CKD is defined by the Kidney Disease Improvement Global Outcomes (KDIGO) working group as CKD-related mineral and bone disorders (CKD-MBD). The last update of the KDIGO guidelines on the conduct in CKD-MBD was published in 2017. The treatment of SHPT is based on 2 strategies: counteracting hyperphosphataemia and suppressing parathyroid hormone (PTH) secretion. Therapy should be based on optimally selected drugs, taking into account additional effects to reduce the risk of chronic complications and side effects. The creation of new drugs with a better safety profile, significant reduction of side effects, and greater efficiency in achieving target serum phosphorus and PTH values forces the gradual replacement of existing treatment with new pharmacotherapies. The aim of this study is to discuss the latest issues (in connection with the latest KDIGO guidelines) regarding the pathomechanism of secondary hyperparathyroidism and the current directions of the therapy in these disorders.

The Importance of α-Klotho in Depression and Cognitive Impairment and Its Connection to Glutamate Neurotransmission-An Up-to-Date Review.

Depression is a serious neuropsychiatric disease affecting an increasing number of people worldwide. Cognitive deficits (including inattention, poor memory, and decision-making difficulties) are common in the clinical picture of depression. Cognitive impairment has been hypothesized to be one of the most important components of major depressive disorder (MDD; referred to as clinical depression), although typical cognitive symptoms are less frequent in people with depression than in people with schizophrenia or bipolar disorder (BD; sometimes referred to as manic-depressive disorder). The importance of α-Klotho in the aging process has been well-documented. Growing evidence points to the role of α-Klotho in regulating other biological functions, including responses to oxidative stress and the modulation of synaptic plasticity. It has been proven that a Klotho deficit may contribute to the development of various nervous system pathologies, such as behavioral disorders or neurodegeneration. Given the growing evidence of the role of α-Klotho in depression and cognitive impairment, it is assumed that this protein may be a molecular link between them. Here, we provide a research review of the role of α-Klotho in depression and cognitive impairment. Furthermore, we propose potential mechanisms (related to oxidative stress and glutamatergic transmission) that may be important in α-Klotho-mediated regulation of mental and cognitive function.

Elucidating the molecular mechanisms underlying the induction of autophagy by antidepressant-like substances in C57BL/6J mouse testis model upon LPS challenge.

The treatment of depression with pharmaceuticals is associated with many adverse side effects, including male fertility problems. The precise mechanisms by which these agents affect testicular cells remain largely unknown, but they are believed to induce cellular stress, which is sensed by the endoplasmic reticulum (ER) and the Golgi apparatus. These organelles are responsible for maintaining cellular homeostasis and regulating signal pathways that lead to autophagy or apoptosis. Therefore, in this study, we aimed to investigate the autophagy, ER, and Golgi stress-related pathways in mouse testis following treatment with antidepressant-like substances (ALS) and ALS combined with lipopolysaccharide (LPS). We found that most ALS and activated proteins are associated with the induction of apoptosis. However, when imipramine (IMI) was combined with NS-398 (a cyclooxygenase-2 inhibitor) after LPS administration, we observed a marked increase in the BECLIN1, Bcl-2, ATG16L, and LC3 expression, which are marker proteins of autophagosome formation. The expression of the BECN1 and ATG16L genes was also high compared to the control, indicating the induction of autophagy processes that may potentially protect mouse testicular cells from death and regulate metabolism in the testis. Our findings may provide a better understanding of the stress-related effects of specific ALS on the testis. Video Abstract.

Changes in working memory induced by lipopolysaccharide administration in mice are associated with metabotropic glutamate receptors 5 and contrast with changes induced by cyclooxygenase-2: Involvement of postsynaptic density protein 95 and down syndrome cell adhesion molecule.

The strength and quality of the signal propagated by the glutamate synapse (Glu) depend, among other things, on the structure of the postsynaptic part and the quality of adhesion between the interacting components of the synapse. Postsynaptic density protein 95 (PSD95), mammalian target of rapamycin (mTOR), and Down syndrome cell adhesion molecule (DSCAM) are components of the proper functioning of an excitatory synapse. PSD95 is a member of the membrane-associated guanylate kinases protein family, mainly located at the postsynaptic density of the excitatory synapse. PSD95, via direct interaction, regulates the clustering and functionality of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and N-methyl-D-aspartic acid (NMDA) receptors at a synapse. Here, the effects of treatment with an antagonist of mGluR5 (MTEP) and NS398 (cyclooxygenase-2, COX-2 inhibitor) on PSD95, mTOR, and DSCAM in the hippocampus (HC) of C57B1/6 J mice using Western blots in the context of learning were examined. Moreover, the sensitivity of selected proteins to lipopolysaccharide (LPS) was monitored. MTEP injected for seven days induced upregulation of PSD95 in HC of mice. The observed effect was regulated by a COX-2 inhibitor and concurrently by LPS. Accompanying alterations in DSCAM protein were found, suggesting changes in adhesion strength after modulation of glutamatergic (Glu) synapse via tested compounds.

Molecular Research on Mental Disorders.

Mental disorders and substance use disorders affect approximately 13% of the world's population [...].

Postsynaptic Proteins at Excitatory Synapses in the Brain-Relationship with Depressive Disorders.

Depressive disorders (DDs) are an increasingly common health problem that affects all age groups. DDs pathogenesis is multifactorial. However, it was proven that stress is one of the most important environmental factors contributing to the development of these conditions. In recent years, there has been growing interest in the role of the glutamatergic system in the context of pharmacotherapy of DDs. Thus, it has become increasingly important to explore the functioning of excitatory synapses in pathogenesis and pharmacological treatment of psychiatric disorders (including DDs). This knowledge may lead to the description of new mechanisms of depression and indicate new potential targets for the pharmacotherapy of illness. An excitatory synapse is a highly complex and very dynamic structure, containing a vast number of proteins. This review aimed to discuss in detail the role of the key postsynaptic proteins (e.g., NMDAR, AMPAR, mGluR5, PSD-95, Homer, NOS etc.) in the excitatory synapse and to systematize the knowledge about changes that occur in the clinical course of depression and after antidepressant treatment. In addition, a discussion on the potential use of ligands and/or modulators of postsynaptic proteins at the excitatory synapse has been presented.

The treatment of depression - searching for new ideas.

Depression is a severe mental health problem that affects people regardless of social status or education, is associated with changes in mood and behavior, and can result in a suicide attempt. Therapy of depressive disorders is based mainly on drugs discovered in the 1960s and early 1970s. Selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) are frontline pharmacological strategies for the medical treatment of depression. In addition, approved by FDA in 2019, esketamine [as nasal spray; N-methyl-D-aspartate (NMDA) receptors antagonist with additional effects on α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, L-type voltage-dependent calcium channel (L-VDCC), opioid receptors, and monoaminergic receptors] is an essential compound in suicide and drug-resistant depression. However, the treatment of depression is burdened with severe side effects, and in many cases, it is ineffective. An equally important issue is the choice of antidepressant therapy in people with comorbid somatic diseases, for example, due to possible interactions with the patient's other drugs. Therefore, there is a great need for new antidepressants with different mechanisms of action and the need to refine the search for new substances. The purpose of this review was to discuss new research directions and new trends that dominate laboratories worldwide. We have reviewed the literature to present new points on the pharmacological target of substances with antidepressant activity. In addition, we propose a new perspective on depressive therapies.

Trade-offs between male fertility reduction and selected growth factors or the klotho response in a lipopolysaccharide-dependent mouse model.

The increasing number of depression cases leads to a greater need for new antidepressant treatment development. It is postulated that antidepressants may harm male fertility, but the cellular mechanism is still poorly understood. The role of growth factors and klotho protein in maintaining normal male reproductive function is well documented. Hence, the study aimed to investigate the effect of the antidepressant drug - imipramine (tricyclic AD), and other substances with antidepressant potential (ALS), administered in combination or in combination with LPS (an animal model of depression) on gene expression and protein synthesis of IGF-2 (insulin-like growth factor 2), TGF-ß1 (transforming growth factor ß1), NGF (nerve growth factor), KGF (keratinocyte growth factor) and protein synthesis of VEGF-A (vascular endothelial growth factor A), IGF-IR (insulin-like growth factor receptor 1), EGFR (epidermal growth factor receptor) and klotho in the testis of mice. Mice were injected intraperitoneally with selected ALS and LPS or 10% DMSO (controls) (n = 7/group) once a day for 14 days. Animals were decapitated and testes collected for RNA and protein purification. PCR and western blot methods were employed for the evaluation of growth factors and klotho expression. The results obtained indicated a decreased level of most of the analyzed genes and proteins, except KGF; its expression increased after treatment with MTEP and IMI administrated individually and after NS-398, and IMI in combination with LPS. Our results may suggest that the tested ALS and LPS can contribute to a reduction of male fertility, but NS-398, IMI, and IMI+NS-398 may also act as stimulants after LPS.

Upregulation of the mGlu5 receptor and COX-2 protein in the mouse brain after imipramine and NS398, searching for mechanisms of regulation.

Imipramine belongs to a group of tricyclic antidepressants (TCAs). It has been also documented that its antidepressant activity connects with the modulation of cytosolic phospholipase A2 (cPLA2) and arachidonic acid (AA) turnover. Through this mechanism, imipramine can indirectly modify glutamate (Glu) transmission. Additionally, it has been shown that chronic treatment with imipramine results in the upregulation of the metabotropic glutamate receptor subtype 5 (mGlu5 receptor) in the hippocampus of rats. Our previous study revealed that manipulation of the AA pathway via inhibition of cyclooxygenase-2 (COX-2) by selective COX-2 inhibitor (NS398) could effectively modulate the behavior of mice treated with imipramine. Here, we hypothesized that COX-2 inhibition could similarly to imipramine influence mGlu5 receptor, and thus NS398 can modulate the effect of imipramine on Glu. Moreover, such regulation changes should correspond with alterations in neurotransmission. Increased cPLA activity after imipramine administration may change the activity of the AA pathway and the endocannabinoid metabolism, e.g., 2-Arachidonyl-glycerol (2-AG). To verify the idea, mGlu5 receptor level was investigated in the hippocampus (HC) and prefrontal cortex (PFC) of mice treated for 7 or 14 days with imipramine and/or COX-2 inhibitor: NS398. Western blot and PCR analyses were conducted. Moreover, the excitatory (Glu) and inhibitory (gamma-aminobutyric acid; GABA) neurotransmitters were measured using HPLC and 2-AG using ELISA. A time-dependent change in mGlu5 receptor and COX-2 protein level, COX-2 expression, and 2-AG level in the PFC after imipramine administration was found. Up-regulation of mGlu5 receptor after NS398 was found in HC and PFC. A structure-dependent shift between excitatory vs. inhibitory transmission was detected when NS398 and imipramine were co-administered.

Methylphenidate for attention-deficit/hyperactivity disorder in adults: a narrative review.

RATIONALE: Psychostimulants, including methylphenidate (MPH), are the mainstay of pharmacotherapy for attention-deficit/hyperactivity disorder (ADHD) in adults. Even though MPH is the most commonly used medication for ADHD these days, there are relatively few resources available that provide comprehensive insight into the pharmacological and clinical features of the compound. OBJECTIVE: The aim of this paper is to provide an up-to-date outline of the pharmacology and clinical utility of MPH for ADHD in adult patients. METHODS: While conducting the narrative review, we applied structured search strategies covering the two major online databases (MEDLINE and Cochrane Central Register of Controlled Trials). In addition, we performed handsearching of reference lists of relevant papers. RESULTS: Methylphenidate exhibits multimodal mechanism of action, working primarily as a dopamine and noradrenaline reuptake inhibitor. It also protects the dopaminergic system against the ongoing 'wearing off' (by securing a substantial reserve pool of the neurotransmitter, stored in the presynaptic vesicles). In placebo-controlled trials, MPH was shown to be moderately effective both against the core ADHD symptoms (standardized mean difference [SMD], 0.49; 95% confidence interval [CI], 0.35-0.64), and the accompanying emotion regulation deficits (SMD, 0.34; 95% CI, 0.23-0.45). The most common adverse events related to long-term treatment with MPH are decreased appetite (~ 20%), dry mouth (15%), heart palpitations (13%), gastrointestinal infections (~ 10%), and agitation/feeling restless (~ 10%). CONCLUSIONS: There is substantial body of evidence to suggest that MPH is an effective and safe treatment option for adults with ADHD.

IGF-1 as selected growth factor multi-response to antidepressant-like substances activity in C57BL/6J mouse testis model.

Insulin-like growth factor (IGF-1) affects almost all cells in the body. Extremely important functions of this growth factor have been demonstrated in the brain and the reproductive system of both, females and males. Also, it is considered as a pro-inflammatory cytokine adjusting tissue homeostasis. However, it seems to play a special role in the male reproductive system and it may be disturbed by the application of antidepressants with different mechanisms of drug action during therapy. To date, the effect of antidepressant-like substances (ALS) on the course of physiological processes in male testicular cells is poorly understood. Therefore, the purpose of the research was to determine the presence, localizationof IGF-1R (insulin-like growth factor 1 ß receptor) and mRNA gene expression of IGF-1R and IGF-1 after administration of 3-[(2-methyl-1,3-tiazol-4-yl)ethynyl]-pyridine (MTEP) and N-[2-(Cyclohexyloxy)-4-nitrophenyl]-methanesulfonamide (NS-398) in the different scheme in the testis of mice. Imipramine was used as a reference drug having a documented interaction with the mGluR5 receptors. The immunohistochemical analyses showed the localization of IGF-1R in Sertoli, Leydig, and germinal cells after all used substances. Differences in receptor localization were observed depending on the drugs applied and the type of analyzed cells. In contrast, there was a significant increase in IGF-1 gene expression after IMI + NS-398 and in IGF-1R after MTEP + NS-398 and IMI + NS-398 administration. It can, therefore, be assumed that the use of a combination of NS-398 with some ALS may run different mechanisms of action and affect the regulation of reproductive function in mouse testis through maintaining homeostasis at the molecular and immunological levels related to IGF.

Vorinostat (SAHA) May Exert Its Antidepressant-Like Effects Through the Modulation of Oxidative Stress Pathways.

Suberoylanilide hydroxamic acid (SAHA/Vorinostat), a potent inhibitor of histone deacetylases (HDACs), is known to possess antidepressant properties. However, the exact mechanisms underlying this activity are unknown. In this study, we evaluated the effect of SAHA on the expression of GluN2A, GluN2B (NMDA receptor subunits), (p-)AMPK, and ΔFos proteins which are an integral part of the signal transduction pathways in the brain and also involved in the pathophysiology of depression as well as the mechanism of antidepressant action. We also measured the concentration of malondialdehyde (MDA - a product of lipid peroxidation). The study was carried out in the prefrontal cortex (PFC) and hippocampus (Hp), brain regions implicated in depression. Although SAHA induced changes in the expression of all the proteins and MDA concentration, the effects differed depending on the drug dose, time, and brain structure involved. SAHA reduced MDA concentration and significantly increased p-AMPK protein expression, indicating it may prevent oxidative stress. SAHA also increased the levels of HDAC3 and NMDA subunits (GluN2A and GluN2B), implying it is neuroprotective and may play a crucial role in synaptic plasticity. Moreover, ΔFosB and FosB levels were significantly elevated, suggesting that SAHA may modulate learning and memory processes. Overall, the data indicate that the Hp might play a pivotal role in the mechanism of action of SAHA, hinting at novel mechanisms it play in the antidepressant and neuroprotective effects of SAHA.

Antidepressant-like Effects of Combined Fluoxetine and Zinc Treatment in Mice Exposed to Chronic Restraint Stress Are Related to Modulation of Histone Deacetylase.

Chronic stress is the key factor contributing to the development of depressive symptoms. Chronic restraint stress (CRS) is well validated and is one of the most commonly used models to induce depressive-like behavior in rodents. The present study aimed to evaluate whether fluoxetine (FLU 5 mg/kg) and zinc (Zn 10mg/kg) given simultaneously induce a more pronounced antidepressant-like effect in the CRS model than both those compounds given alone. Behavioral assessment was performed using the tail suspension and splash tests (TST and ST, respectively). Furthermore, the effects of CRS, FLU and Zn given alone and combined treatment with FLU + Zn on the expression of proteins involved in the apoptotic, inflammatory, and epigenetic processes were evaluated in selected brain structures (prefrontal cortex, PFC; and hippocampus, Hp) using Western blot analysis or enzyme-linked immunosorbent assays (ELISA). The results obtained indicated that three hours (per day) of immobilization for 4 weeks induced prominent depressive symptoms that manifested as increased immobility time in the TST, as well as decreased number and grooming time in the ST. Behavioral changes induced by CRS were reversed by both FLU (5 and 10 mg/kg) or Zn (10 mg/kg). Zinc supplementation (10 mg/kg) slightly increases the effectiveness of FLU (5 mg/kg) in the TST. However, it significantly increased the activity of FLU in the ST compared to the effect induced by FLU and Zn alone. Biochemical studies revealed that neither CRS nor FLU and Zn given alone or in combined treatment alter the expression of proteins involved in apoptotic or inflammatory processes. CRS induced major alterations in histone deacetylase (HDAC) levels by increasing the level of HADC1 and decreasing the level of HADC4 in the PFC and Hp, decreasing the level of HADC6 in the PFC but increasing it in Hp. Interestingly, FLU + Zn treatment reversed CRS-induced changes in HDAC levels in the Hp, indicating that HDAC modulation is linked to FLU + Zn treatment and this effect is structure-specific.

Behavioral consequences of co-administration of MTEP and the COX-2 inhibitor NS398 in mice. Part 2.

Our earlier study demonstrated, that antidepressant-like and also cognitive action of MTEP, a metabotropic glutamate receptor subtype 5 (mGluR5) antagonist, was influenced by cyclooxygenase-2 (COX-2) inhibition in mice. We detected a decrease in the mGluR7 protein level in the hippocampus (HC) of mice co-treated chronically with MTEP and NS398 (a COX-2 inhibitor). We found both antidepressant-like effects and cognitive to be associated with mGlu7 receptor-mediated mechanisms.

Epigenetic marks and their relationship with BDNF in the brain of suicide victims.

BACKGROUND: Suicide is a common phenomenon affecting people of all ages. There is a strong relationship between suicidal ideation and depressive disorders. Increasing number of studies suggest that epigenetic modifications in certain brain areas are the main mechanism through which environmental and genetic factors interact with each other contributing to the development of mental disorders. To verify this hypothesis, some epigenetic marks: H3K9/14ac, HDAC2/3, H3K27me2 and Sin3a, as well as p-S421-MeCP2/MeCP2 were examined. On the other hand, BDNF protein level were studied. MATERIALS AND METHODS: Western blot analysis were performed in the frontal cortex (FCx) and hippocampus (HP) of suicide victims (n = 14) and non-suicidal controls (n = 8). The differences between groups and correlations between selected proteins were evaluated using Mann-Whitney U-test and Spearman's rank correlation. RESULTS: Statistically significant decrease in H3K9/14ac (FCx:↓~23%;HP:↓~33%) combined with increase in HDAC3 (FCx:↑~103%;HP:↑~85% in HP) protein levels in suicides compared to the controls was shown. These alterations were accompanied by an increase in H3K27me2 (FCx:↑45%;HP:↑~59%) and Sin3a (HP:↑50%) levels and decrease in p-S421-MeCP2/MeCP2 protein ratio (HP:↓~55%;FCx:↓~27%). Moreover, reduced BDNF protein level (FCx:↓~43%;HP:↓~28%) in suicides was observed. On the other hand, some significant correlations (e.g. between H3K9/14ac and HDAC2 or between BDNF and p-S421-MeCP2/MeCP2) were demonstrated. CONCLUSIONS: Our findings confirm the role of epigenetic component and BDNF protein in suicidal behavior. Lowered BDNF protein level in suicides is probably due to decrease in histone acetylation and increased level of factors related with deacetylation and methylation processes, including MeCP2 factor, which may operate bidirectionally (an activator or inhibitor of transcription).

Zinc and copper concentration do not differentiate bipolar disorder from major depressive disorder. / Stezenie cynku i miedzi nie róznicuje choroby afektywnej dwubiegunowej i jednobiegunowej.

OBJECTIVES: The aim of this study was to compare the zinc and copper concentration in the group of patients with bipolar disorder (BD) and major depressive disorder (MDD). METHODS: 110 patients with the diagnosis of BD and 114 with MDD were qualified to the study. To assess the levels of microelements, the flame atomic absorption spectrometry (FAAS) was used in the case of zinc and the electrothermal atomic absorption spectrometry (ETAAS) was used in the case of copper. RESULTS: There were no differences between concentration of zinc and copper in remission and depressive phase between patients with BD and MDD. Additionally, there were also no statistically significant differences in comparisons including type I and II, early or late phase of BD and MDD. CONCLUSIONS: The lack of differences in zinc and copper concentrations between patients with bipolar disorder and major depressive disorder might indicate that those disorders have similar etiology.