Four-plate Test Research Articles

Evaluation of tetracycline antibiotics residues in chicken tissues using the four-plate test, ELISA, and HPLC methods in Iran

ABSTRACT Nowadays, various antibiotics are widely used for preventing and treating several diseases and for promoting growth in food-producing animals in different countries of the world. In this assay, edible chicken meat from local markets of Hamadan, a Province of Iran, was examined for residues of tetracycline antibiotics (tetracycline, oxytetracycline and chlortetracycline). In total, 150 samples of breast, wings and thigh tissue were randomly obtained from the local markets of the city of Hamadan. Four-plate tests (FPT), the enzyme-linked immunosorbent assay (ELISA) and high-performance liquid chromatography (HPLC) were used to analyse tetracycline antibiotic (TC) residues, respectively. Results showed that out of 150 samples, 30 samples (24.00%) and 22 samples (14.71%) of carcases were positive or “suspect by antibiotic residues by FPT and ELISA screening method, respectively. The HPLC assay indicated in 7 samples of wings and 12 samples of breast and 18 samples of thigh, residues of TCs were detected. The study revealed that the TCs levels in one sample of wings and three samples of breast and five samples of thigh exceeded the maximum residue level (MRL) reported by the EU. To reduce the TC residues found in edible chicken meat, regulatory authorities should ensure that the chicken would undergo the proper withdrawal period from TCs before slaughtering.

Antibiotic residues in poultry tissues in Iran: A systematic review and meta-analysis.

To control the drug residues in foods, the national Maximum Residue Limits (MRLs) have been determined by the international organizations; however, no regulation has been complied for MRL in food animals in Iran. This study was a systematic review and meta-analysis about studies of antibiotic residues in slaughtered poultry carcasses, in Iran. The information was first collected and analyzed throughout six international databases, and four Iranian national databases. According to the data, the total prevalence of antibiotic residues was obtained as 39.41%, 5.40%, and 0.30% using four-plate test (FPT), High-Performance Liquid Chromatography (HPLC), and Enzyme-linked immuno_sorbent assay (ELISA) methods, respectively. The highest prevalence of the residues was shown in the liver by both methods of HPLC (47.75%) and ELISA (14.35%). Moreover, the total mean of antibiotics was recorded as 71.03ppb and 65.86ppb in different tissues using the HPLC and ELISA method, respectively. Based on this study, we can conclude that the prevalence of antibiotic residue in poultry meat in Iran is high and that this level does not cause health problems for consumers. It is highly recommended to execute tight surveillance strategies from the government in antibiotic monitoring.

Comparison of yogurt test with commercial kit for detection of antibiotic residues in raw and pasteurized milk.

BACKGROUND: Antibiotics are widely used for the treatment of livestock. Their inappropriate usage leads to various disorders in humans as a result of consuming animal products. Milk is among the foods that are significantly affected by consuming antibiotics. OBJECTIVES: The objective of this study was to compare Yoghurt Culture Test (YCT), Four- Plate Test (FPT), and the Copan test for detecting antibiotic residues in raw and pasteurized milk produced in Chaharmahal and Bakhtiari province, Iran. METHODS: A total of 146 raw milk samples and 54 pasteurized milk samples were selected randomly from dairy farms and dairy products suppliers. The presence of antibiotics was evaluated by YCT, FPT, and Copan test. In addition, the sensi-tivity of the three tests for tetracycline and penicillin, as the two common antibiotics in the treatment of animals, was compared. RESULTS: Our findings showed that 8.9% of raw milk and 11% of pasteurized milk samples contained antibiotics. However, the levels of antibiotic residues were higher in 2% of the positive samples than maximum residue levels (MRL). Moreover, significant differences were observed between FPT, YCT, and the Copan test (p 0.05). CONCLUSIONS: The results of this study showed that a low percentage of milk samples contained antibiotic residues higher than the permissible limit. Furthermore, YCT could be used as an inexpensive, easy, and sensitive method for identifying the residues of penicillin and tetracycline in milk.

Evaluating the applicability of the modified four-plate test on the determination of antimicrobial agent residues in pork

The antibiotic residues in 1,022 pork carcass samples, which were collected from 19 areas in Taipei, Taichung and Kaohsiung counties between January and June, 1997, were systematically investigated using a modified four-plate test (MFPT). Four culture media inoculated with 3 strains of bacteria were used; two were inoculated with Bacillus subtilis at pH 6.0 and pH 8.0, and the third and fourth were inoculated with Bacillus cereus and Sarcina lutea, respectively. The identification and quantification of tetracycline residues in the raw meat was performed by bioassay and bioautography. Streptomycin and chloramphenicol in pork carcasses were screened by ELISA and further quantified using the HPLC method. Results showed that using the CNS 5916 method, only 1 out of 1,022 test samples (0.1%) was detected to contain an antimicrobial agent. While using the MFPT method, 4.11% and 0.64% test samples were found to contain tetracycline and streptomycin residues, respectively. No chloramphenicol residue was detected in any tested samples. It was concluded that the MFPT method is practical, sensitive, less expensive, and simple as compared to the CNS 5916 and FPT methods, which are routinely used in Taiwan and the European Community, respectively. MFTP is therefore recommended as an official method to assay the antimicrobial agents in foods.

Assessing Antibiotic Residues in Poultry Eggs from Backyard Production Systems in Chile, First Approach to a Non-Addressed Issue in Farm Animals.

Simple SummaryEggs are a readily available and important food source for low income families that raise chicken in their households. It is therefore important to monitor if these products are safe for human consumption and contain no antibiotic residues that could lead to allergic reactions, intoxication, or antimicrobial resistance. However, little is known about the antimicrobial content of eggs consumed in rural households in Chile. Consequently, the aim of this study was to collect chicken eggs from rural households in the central region of Chile and screen them for antimicrobial activity. The results indicate that most collected eggs (73% of the 83 surveyed households), exhibited antimicrobial activity for at least one of the four tested antimicrobials. These results indicate that household members who consume these eggs are in danger of developing antibiotic-related illnesses and could contribute to antimicrobial resistance. Therefore, further studies are required to identify the exact compounds used to treat the chickens and to establish preventive measures to eradicate antimicrobial presence in their food supply.Eggs are the main product generated from backyard poultry production systems (BPS) because they can quickly be consumed and sold to meet essential family needs. Nevertheless, antimicrobial residues can accumulate in this product. The objective of this study was to evaluate the presence of antimicrobial residues in eggs produced by poultry kept in BPS in central Chile. To assess this, eggs were obtained from 83 BPS and analysed to evaluate the presence of antibiotic residues (families: tetracyclines, beta-lactams, aminoglycosides and macrolides), using a Four-Plate Test screening method for the detection, based on a bacterial growth inhibition method. Results show a lack of biosecurity procedures at BPS level, making these systems susceptible to the dissemination of antimicrobial residues. These include intensive animal production units in the proximity, and the presence of shared watercourses with other farms. Furthermore, 66% of the surveyed owners are indicated as giving pharmacological treatments to their chickens. Eggs from 61 BPS were positive for at least one antimicrobial. Fifty-three BPS were positive for more than one antimicrobial, and one BPS was positive for all four antimicrobials tested. Consequently, there is a risk that poultry eggs produced in BPS in central Chile carry residues of different families of antimicrobials.

Detection of Antimicrobial Drug Residues in Poultry Products by Four-Plate Test Method in Chaharmahal and Bakhtiari Province

Detection of Antimicrobial Drug Residues in Poultry Products by Four-Plate Test Method in Chaharmahal and Bakhtiari Province

Antibiotic residues in the raw and pasteurized milk produced in Northeastern Iran examined by the four-plate test (FPT) method

ABSTRACT The antibiotic residues were investigated in raw and pasteurized milk produced in Neyshabur region, Iran. To this end, 82 milk samples, including raw and pasteurized milk of different brands and local raw milk samples of collection centers, were collected from Neyshabur region in two seasons during 2016. The antibiotic four-plate test (FPT) was performed to examine the presence of tetracycline, flomocaine, sulfonamide, enrofloxacin, aminoglycoside, and macrolide in the samples. The data were analyzed by the chi-squared test and logistic regression analysis to determine significant differences among variables at the significance level of p < .05. The results revealed that, among the 82 milk samples, 16 (47.2%) collected raw milk, 10 (41.6%) raw milk in the factories, and 6 (25%) pasteurized milk samples were positive. The findings showed that the most positive antibiotics belonged to the flomocaine, tetracycline, sulfonamide, and enrofloxacin groups, respectively. However, no aminoglycoside or macrolide was found in the samples. Analysis of milk samples performed in two seasons and the site of the sample collection showed a significant difference in the antibiotic residue content (p < .05). Logistic regression analysis showed that the odds of contamination in winter were 3.73 times that of fall (p = .006). Positive antibiotic residues were present in a large number of milk samples. This study highlights the need for special measures and effective monitoring programs to reduce the hazard of chemical contamination in the Neyshabur region.

Screening for tylosin and other antimicrobial residues in fresh and fermented (nono) cow milk in Delta state, South-South, Nigeria.

Background and Aim:Milk is a food that contains almost all the essential nutrients needed for growth and maintenance for both young and old animals and man. Since quite nutritious and in high demand, dairy products should be free of both chemical and biological contaminants. Unfortunately, antibiotics used in the treatment of infectious diseases in dairy cattle are often seen in their products if withdrawal periods of those drugs are not observed before milking. This study aimed to detect the presence of antibiotics and the level of tylosin in fresh and fermented (nono) milk from cows in Delta state, Nigeria.Materials and Methods:Two hundred and five samples comprising 126 fresh milk and 79 fermented milk (nono) were sampled from Kwale, Ozoro, and Oleh representing one senatorial district of Delta state, South-South Nigeria. They were screened for the presence of tylosin and other antimicrobial residues using four-plate test and tylosin was confirmed with high-performance liquid chromatography.Results:Antibiotic residues were obtained in 76% and 85% of fresh milk and nono, respectively. Tylosin residue was also detected in 24% fresh milk and 11% nono samples at mean concentrations of 14.64±0.69 µg/l and 7.97±0.23 µg/l, respectively. The mean concentrations of tylosin from both milk types were below the recommended maximum residue limit (MRL) of 50 µg/l in dairy.Conclusion:High prevalence of antimicrobial residues in fresh milk and nono shows that consumers in the study area are predisposed to health hazards due to the presence of residues of different antibiotics in fresh milk and nono. Although tylosin was confirmed in both milk products, the mean concentrations were below the MRL. However, it is still very vital to resort to the observance of withdrawal periods and avoid gross misuse of antimicrobials. It is also necessary to emphasize the need for effective prevention of infectious diseases and most importantly create awareness and establish a national antibiotic residue monitoring program in Nigeria.

Comparative analysis of two microbiological tests in the detection of oxytetracycline residue in chicken using ELISA as gold standard

ABSTRACTThe validity of two microbiological methods: Tube (Premi® Test) and Plate (Three Plate Test) Test for the detection of oxytetracycline (OTC) in poultry was done using Enzyme Linked Immunosorbent Assay (ELISA) immunoassay as gold standard. OTC was administered to two groups of birds: intramuscular drug administration (group A) and oral drug administration (group B). Liver and muscle tissue samples from birds in both groups were tested for the presence of OTCwith the Four Plate Test (FPT), Premi® Test and ELISA. For muscle tissues, FPT had a sensitivity of 71.4% and 60%, while Premi® Test had a sensitivity of 57% and 20% for intramuscular and orally treated birds, respectively. For the liver tissues, FPT had 87.5% and 83.5% while Premi® Test had 37.5% and 16.6% sensitivity for intramuscular and orally treated birds, respectively. The two tests had 100% specificity for OTC in tissues of birds from both treatment groups. There is a strong correlation (r = 0.93) between the inhibition zones of FPT and ELISA concentrations in OTC detection. FPT, therefore, has a higher sensitivity for OTC than Premi® Test.

Design, synthesis and evaluation of activity and pharmacokinetic profile of new derivatives of xanthone and piperazine in the central nervous system.

Searching for CNS active cyclic amines derivatives containing heterocyclic xanthone core we designed and synthesized a set of fourteen novel 2- or 4-methylxanthone substituted by alkyl- or aryl-piperazine moieties. The compounds were evaluated in vivo for their potential antidepressant-like activity (in the forced swim test) and anxiolytic-like activity (four-plate test) and their inhibitory effect against rat 5-HT2 receptor was checked. The pharmacokinetic analysis of active compounds done by a non-compartmental approach have shown a rapid absorption of all studied molecules from intraperitoneal cavity and good penetration the blood-brain barrier after i.p. administration with brain to plasma ratios varied from 2.8 to 31.6. Genotoxicity and biotransformation of active compounds were studied. Compound 19 interactions with major classes of GPCRs, uptake systems and ion channels were tested and results indicated that it binds to 5-HT2A, 5-HT2B receptors and sodium channels.

Comparative Screening of Chloramphenicol Residue in Chicken Tissues Using Four Plate Test and Premi®Test Methods

Background: The safety of food with animal origin means that the food consumed is considered as safe when synthetic chemical agents are absent or present at very low concentrations. The aims of the present study were to validate the Premi®Test and four plate test (FPT) methods as well as screen and estimate the occurrence of chloramphenicol (CAP) residue in collected chicken tissues including liver, kidney and thigh muscle from Kermanshah, west of Iran. Methods: A total of 150 chicken samples were purchased from different poultry slaughterhouses in Kermanshah province, west of Iran and subjected to the FPT and Premi®Test. Results: The Premi®Test could not detect CAP residue at concentrations below 3 and 6 ppm in aqueous solution and kidney fluid, respectively. The highest sensitivity of FPT in the detection of CAP residue was optimally found in the agar medium inoculated with Bacillus subtilis at pH 7.2. The Premi®Test was more sensitive than FPT in the kidney fluid and aqueous solution. Regarding FPT results, CAP residue was found in 20% (n=30), 8.66% (n=28) and 11.33% (n=17) of liver, kidney and muscle samples, respectively. In the case of Premi®Test, the most contaminated samples were liver (24%), followed by kidney (22.66%) and muscle (19.33%). Conclusion: It can be concluded that illegal use of CAP in Iranian poultry industries should be taken into account seriously.

Synthesis and activity of di- or trisubstituted N-(phenoxyalkyl)- or N-{2-[2-(phenoxy)ethoxy]ethyl}piperazine derivatives on the central nervous system

Aim of the study was evaluation of anxiolytic, antidepressant, anticonvulsant and analgesic activity in a series of a consistent group of compounds. A series of eleven new N-(phenoxyalkyl)- or N-{2-[2-(phenoxy)ethoxy]ethyl}piperazine derivatives has been obtained. Their affinity towards 5-HT1A, 5-HT2A, 5-HT6, 5-HT7, D2 and α1 receptors has been assessed, and then functional assays were performed. The compounds were evaluated in mice, i.p. for their antidepressant-like (forced swim test), locomotor, anxiolytic-like (four-plate test) activities as well as – at higher doses – for anticonvulsant potential (MES) and neurotoxicity (rotarod). Two compounds (3, 6) were also evaluated for their analgesic activity in neuropathic pain models (streptozocin test, oxaliplatin test) and they were found active against allodynia in diabetic neuropathic pain at 30 mg/kg. Among the compounds, anxiolytic-like, anticonvulsant or analgesic activity was observed but antidepressant-like activity was not. One of the two most interesting compounds is 1-{2-[2-(2,4,6-trimethylphenoxy)ethoxy]ethyl}-4-(2-methoxyphenyl)piperazine dihydrochloride (9), exhibiting anxiolytic and anticonvulsant activity in mice, i.p. 30 min after administration (at 2.5 mg/kg and ED50 = 26.33 mg/kg, respectively), which can be justified by the receptor profile: 5-HT1A Ki = 5 nM (antagonist), 5-HT7 Ki = 70 nM, α1 Ki = 15 nM, D2 Ki = 189 nM (antagonist). Another interesting compound is 1-[3-(2,4,6-trimethylphenoxy)propyl]-4-(4-methoxyphenyl)piperazine dihydrochloride (3), exhibiting anxiolytic, anticonvulsant and antiallodynic activity in mice, i.p., 30 min after administration (at 10 mg/kg, ED50 = 23.50 mg/kg, at 30 mg/kg, respectively), which can be related with 5-HT1A weak antagonism (Ki = 146 nM), or other possible mechanism of action, not evaluated within presented study. Additionally, for the most active compound in the four-plate test (7), molecular modeling was performed (docking to receptors 5-HT1A, 5-HT2A, 5-HT7, D2 and α1A).

Assessment of Oxytetracycline Residue in Cooked and Raw Meat of Chicken Broilers Before and After the End of Official Withdrawal Period

The aim of this study was to determine and to compare the presence of oxytetracycline (OTC) residues in raw and cooked (boiled) meat before and after withdrawal period with the Maximum Residue Limits (MRL) using biological and physicochemical techniques. In animal building of 2000 broiler chickens (Gallus domesticus, breed ISA F15) and under the same conditions, 12 healthy adult chickens were selected and divided in two groups (n = 6 in each group). The sample was treated by Oxytetracycline® 20% (0.4 g/kg) during 3 days. Juices and muscles tissues were sampled twice for this assay: first, the broiler chickens were slaughtered (n = 6) 24 h after the third day of treatment. However, the second sampling (n = 6) was performed 24 h after the end of the withdrawal period. For each portions of sample, the juice meat and muscle tissues samples were collected after cooking at 80 °C during 45 min and after freezing/defrosting for the raw meat. Biological methods consisted of using four plates test (FPT) to pre-screening and Premi®Test to screening. Finally, to confirm and to quantify the accurate level of OTC in positive samples, ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS) measurements were conducted. The FPT test showed that all samples were positive. While the Premi®Test analysis showed negative results for raw meat tested and positive results for juice of meat cooked in both samples. The obtained results using UHPLC-MS/MS methods confirmed the previously results. Thus, the presence of such toxic substances in our diet constitutes a major health risk for consumers, requiring the establishment of an adequate monitoring system. There is a paucity of official withdrawal periods for veterinary medicinal products in cooking meat; a relationship between the concentrations of residues of antibiotics after waiting period and cooking is not established since meat is always cooked before consumption.

MF-8, a novel promising arylpiperazine-hydantoin based 5-HT7 receptor antagonist: In vitro drug-likeness studies and in vivo pharmacological evaluation

We report the in vitro drug-likeness studies and in vivo pharmacological evaluation for a new potent 5-HT7 receptor antagonist MF-8 (5-(4-fluorophenyl)-3-(2-hydroxy-3-(4-(2-methoxyphenyl)piperazin-1-yl)propyl)-5-methylhydantoin). The in vitro tests showed good permeability, very good metabolic stability, low risk of drug-drug interactions and satisfying safety profile. Moreover, MF-8 showed excellent antidepressant-like activity in the forced swim test in rodents and promising anxiolytic-like activity in the four-plate test in mice. Regarding the potent affinity, high selectivity and antagonistic activity of MF-8 for the 5-HT7 receptor as well as excellent drug – like properties in vitro and confirmed in vivo pharmacological activity, MF-8 should be considered as a very significant molecule in the search for a new class of anti-depressant drugs.

Comparison of the Psychopharmacological Effects of Tiletamine and Ketamine in Rodents

The glutamate N-methyl-d-aspartate (NMDA) receptor antagonist ketamine (KET) produces rapid and sustained antidepressant effects in patients. Tiletamine (TIL; 2-ethylamino-2-thiophen-2-yl-cyclohexan-1-one) is another uncompetitive NMDA receptor antagonist, used in a medical (veterinary) setting as an anesthetic tranquilizer. Here, we compared the behavioral actions of KET and TIL in a variety of tests, focusing on antidepressant-like and dissociative-like effects in mice and rats. The minimum effective doses of KET and TIL were 10 mg/kg to reduce mouse forced swim test immobility and 15 mg/kg to reduce marble-burying behavior. However, at similar doses, both compounds diminished locomotor activity and disturbed learning processes in the mouse passive avoidance test and the rat novel object recognition test. KET and TIL also reduced social behavior and accompanying 50-kHz “happy” ultrasonic vocalizations (USVs) in rats. TIL (5–15 mg/kg) displayed additional anxiolytic-like effects in the four-plate test. Neither KET nor TIL affected pain response in the hot plate test. Examination of the “side effects” revealed that only at the highest doses investigated did both compounds produce motor deficits in the rotarod test in mice. While KET produced behavioral effects at doses comparable between species, in the rats, TIL was ~10 times more potent than in the mice. In summary, antidepressant-like properties of both KET and TIL are similar, as are their adverse effect liabilities. We suggest that TIL could be an alternative to KET as an antidepressant with an additional anxiolytic-like profile.

Determination of Antibiotic Residues in Pasteurized and Raw Milk in Maragheh and Bonab Counties by Four Plate test (FPT) Method

Determination of Antibiotic Residues in Pasteurized and Raw Milk in Maragheh and Bonab Counties by Four Plate test (FPT) Method

Search for new potential anticonvulsants with anxiolytic and antidepressant properties among derivatives of 4,4-diphenylpyrrolidin-2-one.

The aim of this study was to synthesize a series of new N-Mannich bases derived from 4,4-diphenylpyrrolidin-2-one having differently substituted 4-phenylpiperazines as potential anticonvulsant agents with additional (beneficial) pharmacological properties. The target compounds 8-12 were prepared in one step from the 4-substituted phenylpiperazines, paraformaldehyde, and synthesized 4,4-diphenylpyrrolodin-2-one (7) by a Mannich-type reaction. The obtained compounds were assessed and tested for their anticonvulsant activity in two screening mouse models of seizures, i.e., the maximal electroshock (MES) test and in the subcutaneous pentylenetetrazole (scPTZ) test. The effect of these compounds on animals' motor coordination was measured in the rotarod test. A selected 4,4-diphenyl-1-((4-phenylpiperazin-1-yl)methyl)pyrrolidin-2-one (8) was evaluated in vivo for its anxiolytic- and antidepressant-like properties. Its impact on animals' locomotor activity was also evaluated. Compound 8 showed protection (25%) in the MES and in the scPTZ tests at the dose of 100mg/kg and was not neurotoxic. In the four-plate test, compound 8 at the dose of 30mg/kg showed a statistically significant (p<0.05) anxiolytic-like activity. In the forced swim test, it reduced the immobility time by 24.3% (significant at p<0.05), which indicates its potential antidepressant-like properties. In the locomotor activity test, compound 8 significantly reduced animals' locomotor activity by 79.9%. The results obtained make a new derivative of 4,4-diphenyl-1-((4-phenylpiperazin-1-yl)methyl)pyrrolidin-2-one (8) a promising lead structure for further development.

Evaluation of antidepressant-like and anxiolytic-like activity of purinedione-derivatives with affinity for adenosine A2A receptors in mice.

It has recently been suggested that the adenosine A2A receptor plays a role in several animal models of depression. Additionally, A2A antagonists have reversed behavioral deficits and exhibited a profile similar to classical antidepressants. In the present study, imidazo- and pyrimido[2,1-f]purinedione derivatives (KD 66, KD 167, KD 206) with affinity to A2A receptors but poor A1 affinity were evaluated for their antidepressant- and anxiolytic-like activity. The activity of these derivatives was tested using a tail suspension and forced swim test, two widely-used behavioral paradigms for the evaluation of antidepressant-like activity. In turn, the anxiolytic activity was evaluated using the four-plate test. The results showed the antidepressant-like activity of pyrimido- and imidazopurinedione derivatives (i.e. KD 66, KD 167 and KD 206) in acute and chronic behavioral tests in mice. KD 66 revealed an anxiolytic-like effect, while KD 167 increased anxiety behaviors. KD 206 had no effect on anxiety. Furthermore, none of the tested compounds increased locomotor activity. Available data support the proposition that the examined compounds with adenosine A2A receptor affinity may be an interesting target for the development of antidepressant and/or anxiolytic agents.

HBK-7 — A new xanthone derivative and a 5-HT1A receptor antagonist with antidepressant-like properties

Xanthone derivatives possess many biological properties, including neuroprotective, antioxidant or antidepressant-like. In this study we aimed to investigate antidepressant- and anxiolytic-like properties of a new xanthone derivative – 6-methoxy-4-[4-(2-methoxyphenyl)piperazin-1-yl]-9H-xanthen-9-one (HBK-7), as well as its possible mechanism of action, and the influence on cognitive and motor function. HBK-7 in our earlier studies showed high affinity for serotonergic 5-HT1A receptor. We determined the affinity of HBK-7 for CNS receptors and transporters using radioligand assays and examined its intrinsic activity towards 5-HT1A receptor. We evaluated antidepressant- and anxiolytic-like activity of HBK-7 in the mouse forced swim test, and four-plate test, respectively. We examined the influence on locomotor activity in mice to determine if the effect observed in the forced swim test was specific. We used step-through passive avoidance and rotarod tests to evaluate the influence of HBK-7 on cognitive and motor function, respectively. HBK-7 showed moderate affinity for dopaminergic D2 receptor and very low for serotonergic 5-HT2A, adrenergic α2 receptors, as well as serotonin transporter. Functional studies revealed that HBK-7 was a 5-HT1A receptor antagonist. HBK-7 (10mg/kg) decreased immobility time in the forced swim test. Combined treatment with sub-effective doses of HBK-7 and fluoxetine reduced immobility of mice in the forced swim test. Pretreatment with p-chlorophenylalanine and WAY-100,635 antagonized the antidepressant-like effect of HBK-7. Neither of the treatments influenced locomotor activity of mice. HBK-7 at antidepressant-like dose did not impair memory or motor coordination in mice. We demonstrated that HBK-7 was a 5-HT1A receptor antagonist with potent, comparable to mianserin, antidepressant-like activity. HBK-7 mediated its effect through serotonergic system and its antidepressant-like action required the activation of 5-HT1A receptors. At active dose it did not influence cognitive and motor function. Since 5-HT1A receptor antagonists may accelerate the occurrence of antidepressant effect, our findings highlight their potential as future antidepressants.

The antidepressant- and anxiolytic-like activities of new xanthone derivative with piperazine moiety in behavioral tests in mice.

Objectives:Xanthones are flavonoids with numerous activities, including antioxidant, antidepressant., or anxiolytic-like. Therefore, the aim of our study was to determine antidepressant- and anxiolytic-like properties of four xanthone derivatives (3-chloro-5-[(4-methylpiperazin-1-yl)methyl]-9H-xanthen-9-one dihydrochloride [HBK-5], 6-methoxy-2-[(4-methylpiperazin-1-yl) methyl]-9H-xanthen-9-one dihydrochloride, 2-[(4-benzylpiperazin-1-yl) methyl]-6-methoxy-9H-xanthen-9-one dihydrochloride, 2-{[4-(2-methoxyphenyl) piperazin-1-yl] methyl}-9H-xanthen-9-one hydrochloride), as well as the influence on cognitive and motor function of active compounds, using animal models.Materials and Methods:To determine the antidepressant-like activity, we used forced swim test (FST) and tail suspension test (TST) in mice. We evaluated anxiolytic-like properties in the four-plate test in mice. We studied the influence on cognitive and motor function in passive avoidance step-through and chimney tests, respectively.Results:The antidepressant-like activity (in both FST and TST) showed only HBK-5. Moreover, the compound was also active in the four-plate test, which suggests that it possessed anxiolytic-like properties. HBK-5 did not cause any cognitive and motor deficits in mice at antidepressant- and anxiolytic-like doses.Conclusions:HBK-5 may have potential in the treatment of depression or anxiety disorders, but this issue needs further studies.