Design and synthesis of novel dithiazole carboxylic acid Derivatives: In vivo and in silico investigation of their Anti-Inflammatory and analgesic effects.

Inflammation is a complex set of interactions that can occur in tissues as the body's defensive response to infections, trauma, allergens, or toxic compounds. Therefore, in almost all diseases, it can be observed because of primary or secondary reasons. Since it is important to control and even eliminate the symptoms of inflammation in the treatment of many diseases, anti-inflammatory and analgesic drugs are always needed in the clinic. Therefore, the discovery of new anti-inflammatory/analgesic drugs with increased effectiveness and safer side effect profiles is among the popular topics of medicinal chemistry. Therefore, in this study, in order to synthesize and diversify new molecules, we focused on the N,N-dithiazole carboxylic acid core and linked it with the chalcone functional group. The final eleven molecules were analyzed via HRMS, 1H NMR, and 13C NMR. The antinociceptive effects of the test compounds were examined by tail-clip, hot-plate, and formalin methods in mice, while their anti-inflammatory activities were investigated by carrageenan-induced inflammation tests in rats. The motor activities of the experimental animals were evaluated using an activity-meter device. Obtained findings revealed that none of the test compounds (10 mg/kg) were effective in the tail-clip and hot-plate tests. However, compounds 4b, 4c, 4f, 4 h, and 4 k in the serial shortened the paw-licking times of mice in the late phase of the formalin test indicating that these compounds had peripherally-mediated antinociceptive effects. The same compounds, moreover, showed potent anti-inflammatory effects by significantly reducing paw edema of rats in the inflammation tests. To provide an approach to pharmacological findings regarding possible mechanisms of action, the binding modes of the most active compounds were investigated by in silico approaches. The results of molecular docking studies indicated that the anti-inflammatory and analgesic activities of the compounds might be related to the inhibition of both COX-1 and COX-2 isoenzymes. Findings obtained from in silico studies showed that 4 k, which was chosen as a model for its analogs in the series, forms strong bindings to the basic residues (Arg120, Tyr355), side pocket loop area and deep hydrophobic regions of the enzyme. Moreover, results of the molecular dynamics simulation studies revealed that ligand-COX enzyme complexes are quite stable. Obtained results of in vivo and in silico studies are in harmony, and all together point out that compounds 4b, 4c, 4f, 4 h, and 4 k have significant anti-inflammatory and analgesic activities with good ADME profiles. The potential of the derivatives, whose pharmacological activities were revealed for the first time in this study, as anti-inflammatory and analgesic drug candidates, needs to be evaluated through comprehensive clinical studies.

Pharmacological and Toxicological Screening of Novel Benzimidazole-Morpholine Derivatives as Dual-Acting Inhibitors.

The aim of this study was to investigate acetylcholinesterase (AChE), monoamine oxidase A (MAO-A), monoamine oxidase B (MAO-B), cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) enzyme inhibitory, and antimicrobial activities of a new series of 2-(4-substituted phenyl)-1-[2-(morpholin-4-yl)ethyl]-1H-benzimidazole derivatives, for their possible use as multi-action therapeutic agents. Target compounds (n = 15) were synthesized under microwave irradiation conditions in two steps, and their structures were elucidated by FT-IR, ¹H-NMR, 13C-NMR and high resolution mass spectroscopic analyses. Pharmacological screening studies revealed that two of the compounds (2b and 2j) have inhibitory potential on both COX-1 and COX-2 enzymes. In addition, cytotoxic and genotoxic properties of the compounds 2b, 2j and 2m were investigated via the well-known MTT and Ames tests, which revealed that the mentioned compounds are non-cytotoxic and non-genotoxic. As a concise conclusion, two novel compounds were characterized as potential candidates for treatment of frequently encountered inflammatory diseases.

Effect of benzothiazole/piperazine derivatives on intracerebroventricular streptozotocin-induced cognitive deficits.

BACKGROUND: In this study, benzothiazole-piperazine compounds were synthesized by condensing the functional groups of donepezil (DNP), FK-960, and sabeluzole, which are known to have therapeutic potential against Alzheimer's disease, with the aim of obtaining new and potent anti-Alzheimer agents. METHODS: Initially, acetylcholinesterase/butyrylcholinesterase enzyme inhibition activities of the synthesized test compounds were investigated by Ellman's method. Effects of the compounds on a streptozotocin (STZ) model of Alzheimer's disease (SMAD) were investigated in rats. SMAD was established by intracerebroventricular (icv) injection of STZ (3 mg/kg), bilaterally. The elevated plus maze, Morris water maze, and active avoidance tests were used to examine the effects of test compounds (1, 5, and 10 mg/kg) on learning and memory parameters of icv STZ-injected rats. Effects of the test compounds on spontaneous locomotor activities of rats were examined with the activity cage test. RESULTS: The compounds B2-B5 and DNP exhibited significant selective inhibitory potencies against acetylcholinesterase. Compounds B2 and B3 at 10 mg/kg doses and compounds B4 and B5 at 5 and 10 mg/kg doses, as well as the reference drug DNP (1 and 3 mg/kg), significantly improved the learning and memory parameters of animals in all cognition tests. None of the test compounds changed spontaneous locomotor activities. CONCLUSION: Results of the present study revealed that compounds B2-B5 repaired the parameters related to the learning and memory deficits of icv STZ-injected rats. Potencies of these test compounds were comparable to the activity of DNP.

The effect of simvastatin treatment on behavioral parameters, cognitive performance, and hippocampal morphology in rats fed a standard or a high-fat diet.

The aim of this study was to examine the effect of simvastatin (SMV), a 3-hydroxy-3-methyl-glutaryl-CoA reductase inhibitor, in rats fed with a standard or a high-fat diet (HFD) throughout the prenatal and the postnatal periods. The emotional status of the animals was evaluated by elevated plus-maze and modified forced swimming tests, whereas cognitive performance was assessed by a Morris water maze task. Morphological changes in the hippocampus were examined by design-based stereology. HFD exposure significantly increased blood serum triglycerides without altering cholesterol levels relative to the controls. After four weeks of oral SMV (5 mg/kg) administration, serum triglycerides reverted to the control level. SMV caused significant anxiolytic, antidepressant-like, and nootropic effects in animals fed the standard diet. In the HFD group, enhanced anxiety and depression, and reduced cognitive performances of animals were reversed by SMV treatment. Although a total volume estimation of the hippocampal subfields indicated no significant change among the groups, the total number of pyramidal neurons decreased significantly in animals fed the HFD; following SMV treatment, this detrimental effect was reversed. In conclusion, chronic SMV administration has significant therapeutic potential for the treatment of affective and cognitive disorders with or without altering the serum lipid profiles.

Synthesis of thiadiazole derivatives bearing hydrazone moieties and evaluation of their pharmacological effects on anxiety, depression, and nociception parameters in mice.

Novel thiadiazole derivatives bearing hydrazone moieties were synthesized through the reaction of 2-[(5-methyl-1,3,4-thiadiazol-2-yl)thio)]acetohydrazide with aldehydes/ketones. The chemical structures of the compounds were elucidated by (1)H-NMR, (13)C-NMR, MS-FAB spectral data, and elemental analyses. Behavioral effects of the test compounds in mice were examined by hole-board, activity cage, tail suspension and modified forced swimming tests (MFST). Antinociceptive activities were evaluated using the hot-plate and tail-clip methods. Results of the experiments indicated that the test compounds did not significantly change the exploratory behaviors or locomotor activities of animals in the hole-board and activity cage tests, respectively. Administration of the reference drug fluoxetine (10 mg/kg) and compounds 3a, 3b, 3c, 3j, 3k, and 3l significantly shortened the immobility times of animals in the tail suspension and MFST tests, indicating the antidepressant-like effects of these derivatives. Morphine (10 mg/kg) and compounds 3a, 3b, 3c, 3d, 3e, 3j, 3k, and 3l increased the reaction times of mice in both the hot-plate and tail-clip tests, indicating the antinociceptive effects of these compounds. To the best of our knowledge, this is the first study of central nervous system activities of chemical compounds carrying thiadiazole and hydrazone moieties together on their structures.

Effects of Hypericum montbretti extract on the central nervous system and involvement of GABA (A)/Benzodiazepine receptors in its pharmacological activity.

The present study was undertaken to investigate the putative activity of a methanol extract of Hypericum montbretti (Guttiferae) on the central nervous system. Rutin (1519 ppm) and quercitrin (784 ppm) were identified as the major phenolic compounds in the extract. When administered at 25, 50 and 100 mg/kg doses, the extract decreased the total number of head-dipping behaviours performed by mice during a hole-board test. Administration of both the extract and diazepam (2 mg/kg) reduced spontaneous locomotory activity, potentiated hexobarbital (60 mg/kg)-induced sleeping parameters and prevented pentylenetetrazole (80 mg/kg)-induced seizures relative to the controls. These findings are the first to indicate the sedative and anticonvulsant activities of H. montbretti extract. Atropine (2 mg/kg) and naloxone (5 mg/kg) pre-treatment did not reverse the sedative effect, indicating that muscarinic and opioidergic mechanisms did not contribute to the pharmacological action. However, pre-treatment with flumazenil (a benzodiazepine receptor antagonist) reversed both the sedative and anticonvulsant effects induced by a 100 mg/kg dose of the extract, indicating the involvement of the GABA(A)-benzodiazepine receptor complex. In conclusion, H. montbretti extract is a novel candidate as a sedative and anticonvulsant drug for the treatment of sleep disorders and for the prevention of epileptic seizures.

Effects of insulin and St. John's Wort treatments on anxiety, locomotory activity, depression, and active learning parameters of streptozotocin-diabetic rats.

The aim of this work was to investigate the effects of St. John's Wort (SJW) extract treatment on behavioral changes arising in streptozotocin (STZ)-diabetic rats. Plus-maze, activity cage, modified forced swimming, and active avoidance tests were performed for evaluating exploratory behaviors, spontaneous locomotor activities, depression levels, and learning parameters of animals, respectively. Obtained data exhibited a diabetes mellitus (DM)-induced increase in anxiety and depression levels, decrease in spontaneous locomotor activities, and impairment of learning parameters in rats even in the early stages of the disease. Daily insulin replacement (2 IU/kg/day) could not restore these impaired parameters completely, indicating the need of novel therapeutic approaches. SJW extract (125 and 250 mg/kg) treatments for seven days provided significant improvement in all of the impaired parameters observed in this study, probably due to its antidiabetic and central nervous system (CNS)-related effects. Based on the findings of the present study, it may be suggested that SJW extracts may be of help to diabetic patients suffering from depressive moods, sleeping disturbances, and cognitive deficits and may provide a new potential alternative for the treatment of psychiatric complications of diabetes.

Effects of hawthorn seed and pulp extracts on the central nervous system.

CONTEXT: Investigating potential central nervous system (CNS) activities of Crataegus monogyna Jacq. (Rosaceae), hawthorn, fruit extracts. OBJECTIVE: Evaluating CNS effects and analgesic activities of hawthorn fruit extracts based on the traditional uses of the plant for neurosedative and pain killer actions. MATERIALS AND METHODS: Effects of hawthorn pulp (HPE) and seed extracts (HSE) at the dose range of 1-1000 mg/kg were examined on anxiety level, spontaneous locomotor activity, motor coordination, and nociceptive perception of mice. Morphine was used as a reference drug. RESULTS: HPE (100-1000 mg/kg) and HSE (10-1000 mg/kg) significantly decreased not only the exploratory behaviors in hole-board experiments, but also the spontaneous locomotor activities in activity cage tests. The same doses of extracts were found to be ineffective in Rota-Rod tests of mice. In tail-clip, hot-plate, and acetic acid-induced writhing tests, quite potent and dose-dependent analgesic activities were seen at 100-1000 mg/kg doses of HPE and 10-1000 mg/kg doses of HSE. Analgesic effects observed in all analgesia tests were antagonized by naloxone. DISCUSSION: Significant and dose-dependent decreases in spontaneous locomotor activities and exploratory behaviors of animals suggested CNS depressant activities of both extracts. Complete naloxone antagonism in all applied analgesia tests indicated opioid-related analgesic activities of both extracts. CONCLUSION: These findings seem to support the traditional use of this plant to treat stress, nervousness, sleep disorders, and pain control.

Effects of some 1,3,5-trisubstitued-2-pyrazoline derivatives on depression and anxiety parameters of mice.

The aim of the present study was examining the effects of some 1,3,5-trisubstituted-2-pyrazoline derivatives on depression, anxiety and spontaneous locomotor activity parameters of mice. None of the compounds was effective at 50 mg/kg dose whereas at 100 and 200 mg/kg, pyrazoline-benzoxazole derivative test compound 4a and pyrazoline-benzimidazole derivative test compound 4d in the series were exhibited significant antidepressant effects in modified forced swimming tests. These two pyrazolines decreased the immobility and increased the swimming times of mice without any change in climbing durations suggesting the antidepressant-like effects of the test compounds. In spite of significant antidepressant effect, none of the compounds changed the exploratory parameters in hole-board tests or total numbers of spontaneous locomotor activities in activity cage measurements at any of the applied doses. In other words, neither anxiolytic nor sedative effects induced by the test compounds. The results obtained from this study supported the previous findings reporting the antidepressant activities of pyrazoline derivative compounds. Exact mechanism of the antidepressant action exhibited in the present study need to be clarified with further detailed investigations.