Zebrafish as an Animal Model in Cannabinoid Research

Cannabinoids are active substances present in plants of the Cannabis genus. Both the Food and Drug Administration (FDA) and European Medicines Agency (EMA) have approved several medicinal products containing natural cannabinoids or their synthetic derivatives for the treatment of drug-resistant epilepsy, nausea and vomiting associated with cancer chemotherapy, anorexia in AIDS patients, and the alleviation of symptoms in patients with multiple sclerosis. In fact, cannabinoids constitute a broad group of molecules with a possible therapeutic potential that could be used in the management of much more diseases than mentioned above; therefore, multiple preclinical and clinical studies on cannabinoids have been carried out in recent years. Danio rerio (zebrafish) is an animal model that has gained more attention lately due to its numerous advantages, including easy and fast reproduction, the significant similarity of the zebrafish genome to the human one, simplicity of genetic modifications, and body transparency during the early stages of development. A number of studies have confirmed the usefulness of this model in toxicological research, experiments related to the impact of early life exposure to xenobiotics, modeling various diseases, and screening tests to detect active substances with promising biological activity. The present paper focuses on the current knowledge of the endocannabinoid system in the zebrafish model, and it summarizes the results and observations from studies investigating the pharmacological effects of natural and synthetic cannabinoids that were carried out in Danio rerio. The presented data support the notion that the zebrafish model is a suitable animal model for use in cannabinoid research.

Changes in Physicochemical and Bioactive Properties of Quince (Cydonia oblonga Mill.) and Its Products

Quince (Cydonia oblonga Miller) is a plant that is commonly cultivated around the world, known for centuries for its valuable nutritional and healing properties. Although quince fruit are extremely aromatic, due to their high hardness and sour, astringent, and bitter taste, they are not suitable for direct consumption in an unprocessed form. However, they are an important raw material in fruit processing, e.g., in the production of jams, jellies, and juices. Quince fruits fall under the category of temperate fruits, so their shelf life can be predicted. Considering that technological processing affects not only the organoleptic properties and shelf life but also the functional properties of fruits, the aim of this research was to determine the impact of various types of technological treatments on the physicochemical and bioactive properties of quince fruit. In fresh, boiled, and fried fruits and in freshly squeezed quince fruit juice, basic parameters, such as the content of dry matter, moisture, soluble solids (°Brix), pH, total acidity, water activity, and color parameters (L*a*b*) were determined. The content of key bioactive ingredients, i.e., tannins, carotenoids, flavonoids, phenolic acids, and total polyphenols, was also determined, as well as the antioxidant activity of raw and technologically processed (cooked, fried, and squeezed) quince fruits. The conducted research showed that fresh quince fruit and processed quince products can be a very good source of bioactive ingredients in the diet, such as tannins (3.64 ± 0.06 mg/100 g in fresh fruit; from 2.22 ± 0.02 mg/100 g to 5.59 ± 0.15 g/100 g in products), carotenoids (44.98 ± 0.18 mg/100 g in fresh fruit; from 141.88 ± 0.62 mg/100 g to 166.12 ± 0.62 mg/100 g in products), and polyphenolic compounds (246.98 ± 6.76 mg GAE/100 g in fresh fruit; from 364.53 ± 3.76 mg/100 g to 674.21 ± 4.49 mg/100 g in products). Quince fruit and quince products are also characterized by high antioxidant properties (452.41 ± 6.50 µM TEAC/100 g in fresh fruit; 520.78 ± 8.56 µM TEAC/100 g to 916.16 ± 6.55 µM TEAC/100 g in products). The choice of appropriate technological processing for the quince fruit may allow producers to obtain high-quality fruit preserves and act a starting point for the development of functional products with the addition of quince fruit in its various forms, with high health-promoting values and a wide range of applications in both the food and pharmaceutical industries.

The Sensory Quality and the Physical Properties of Functional Green Tea-Infused Yoghurt with Inulin

The purpose of this study was to investigate the influence of the addition of inulin (3%, 6% and 9%) to green tea-infused set type yoghurt on its sensory quality and physical properties. Yogurts were made by combining green tea with milk and inulin and inoculated with freeze-dried starter cultures YO-122. Incubation was conducted at 43 °C for approximately 4.5 h until a pH value of 4.5–4.6 was achieved. For the prepared yoghurts, a panel of experts (n = 10) was selected, characterized 35 attributes and conducted a sensory quality assessment of these yoghurts using the Quantitative Descriptive Profile method. Additionally, instrumental analyses such as yield stress, adhesiveness, firmness, physical stability and color parameters were also carried out. The use of green tea infusion increased the perception of green tea flavor, bitterness, astringency, dark color of the yoghurt and the existing whey, which worsened the overall sensory quality of the yoghurt. The addition of inulin (9%) to the green tea yoghurt, increased the perception of sweet, peach flavor and aroma and improved the firmness of the yoghurt while reducing the perception of sour taste, which improved the sensory quality of the yoghurt. Both inulin and green tea affected the physical properties of the yoghurts, causing an increase in the yield stress (43%, and 20%, respectively) and deteriorated the stability of the yoghurts. Green tea affected the color of the yoghurts, causing the lightness to decrease. The L* parameter decreased from 89.80 for the control sample to 84.42 for the green tea infused yoghurt. The use of infused green tea in yoghurt production makes it necessary to use ingredients that will neutralize its adverse effects on sensory quality and physical parameters of yoghurt, and such an additive can be prebiotic fiber–inulin at a concentration of 9%.

Application of principal component analysis with instrumental analysis and sensory evaluation for assessment of chicken breast meat juiciness

1. The objectives of this study were to use principal component analysis (PCA) to analyse the variability of the three instrumental and 14 descriptive sensory properties of chicken breast meat. The meat was cooked until the internal temperature reached 85°C and further cooked for 0, 20, and 40 min. The second objective was to identify the most critical variables for assessing meat juiciness.2. Cooking loss and moisture content exhibited high correlation with sensorial moisture release and mouth feel.3. The distribution of objects on the axes of the first two principal components (PCs) enabled the identification of three groups undergoing different cooking durations. The four major PCs explained 80.0% of the total variability.4. Cooking loss, moisture content, water-holding capacity, sensorial moisture release and mouth feel were demonstrated as the most effective variables for the first two PCs. PCA with instrumental and sensory analyses proved an effective procedure for systematically and comprehensively judging chicken meat juiciness.

Zebrafish as an Animal Model for Testing Agents with Antidepressant Potential

Depression is a serious mental disease that, according to statistics, affects 320 million people worldwide. Additionally, a current situation related to the COVID-19 pandemic has led to a significant deterioration of mental health in people around the world. So far, rodents have been treated as basic animal models used in studies on this disease, but in recent years, Danio rerio has emerged as a new organism that might serve well in preclinical experiments. Zebrafish have a lot of advantages, such as a quick reproductive cycle, transparent body during the early developmental stages, high genetic and physiological homology to humans, and low costs of maintenance. Here, we discuss the potential of the zebrafish model to be used in behavioral studies focused on testing agents with antidepressant potential.

The Sensory Quality and the Textural Properties of Functional Oolong Tea-Infused Set Type Yoghurt with Inulin

Set type yoghurts are characterised by a semi-solid texture, which is created during the fermentation process. The tea infusion in this type of yoghurt production can influence the quality of the final product. Therefore, the aim of the experiment was to evaluate the influence of the addition of 3, 6 and 9% inulin to oolong tea-infused yoghurts on the sensory quality. It has been evaluated by trained experts using a Quantitative Descriptive Profile analysis and by consumers using hedonic scaling, as well as on instrumentally evaluated features such as texture, stability and visual parameters. The addition of oolong tea to yoghurt resulted in positive changes in the perception of sweet, peach and nectar odours and flavours, and also creaminess, as well as negative changes in the presence of a bitter taste, the whey presence and a colour intensification towards dark cream (p ≤ 0.05). The addition of inulin to the tested oolong tea yogurts caused a decrease in the whey presence and brightened the yoghurt's colour (6% and 9%, p ≤ 0.05, respectively), as well as an improved creaminess and an increase in the sweet taste of the yoghurt. It was also observed that the addition of oolong tea deteriorated the instrumentally evaluated texture of the set yoghurts, while inulin at a higher concentration (9%, p ≤ 0.05) increased the firmness and adhesiveness. Moreover, the addition of inulin also had a positive effect on the yoghurt's stability. The addition of inulin to oolong tea-infused set yoghurts may be valuable both as a source of prebiotic fibre in functional products and as a factor improving the quality of these products.

The Interaction of Selective A1 and A2A Adenosine Receptor Antagonists with Magnesium and Zinc Ions in Mice: Behavioural, Biochemical and Molecular Studies

The purpose of the study was to investigate whether the co-administration of Mg²⁺ and Zn²⁺ with selective A1 and A2A receptor antagonists might be an interesting antidepressant strategy. Forced swim, tail suspension, and spontaneous locomotor motility tests in mice were performed. Further, biochemical and molecular studies were conducted. The obtained results indicate the interaction of DPCPX and istradefylline with Mg²⁺ and Zn²⁺ manifested in an antidepressant-like effect. The reduction of the BDNF serum level after co-administration of DPCPX and istradefylline with Mg²⁺ and Zn²⁺ was noted. Additionally, Mg²⁺ or Zn²⁺, both alone and in combination with DPCPX or istradefylline, causes changes in Adora1 expression, DPCPX or istradefylline co-administered with Zn²⁺ increases Slc6a15 expression as compared to a single-drug treatment, co-administration of tested agents does not have a more favourable effect on Comt expression. Moreover, the changes obtained in Ogg1, MsrA, Nrf2 expression show that DPCPX-Mg²⁺, DPCPX-Zn²⁺, istradefylline-Mg²⁺ and istradefylline-Zn²⁺ co-treatment may have greater antioxidant capacity benefits than administration of DPCPX and istradefylline alone. It seems plausible that a combination of selective A1 as well as an A2A receptor antagonist and magnesium or zinc may be a new antidepressant therapeutic strategy.

Assessment of Chokeberry Powders Quality Obtained Using an Innovative Fluidized-Bed Jet Milling and Drying Method with Pre-Drying Compared with Convection Drying

There is a need and great interest among food producers in obtaining powders from fruit and vegetables of both high nutritional value and sensory qualities superior to those hitherto obtained by convection drying (CD) and spray drying methods and cheaper to prepare than the sublimation method. This study is focused on whether powders can be obtained from fruit berries with a sticky structure, using the chokeberry (Aronia melanocarpa) as a test example, by a combined fluidized-bed jet milling and drying (FBJD) of pre-dried fruit by CD to an adequate water activity (a_w). The pre-drying step reduced sticking between fruit particles during the simultaneous drying and grinding processes of the FBJD method in order to obtain powders of desired granulation. Three different pre-drying temperatures of 50, 60, and 70 °C were tested for levels of microorganisms in chokeberries at a water activity of 0.4. Vitamin C content and antioxidant properties were also examined along with polyphenol separation. Fruit pre-dried at 60-70 °C had significantly higher vitamin C and polyphenolic content and greater antioxidant properties than those pre-dried at 50 °C. Further studies were thus undertaken on powders pre-dried at 70 °C in which antioxidant properties, vitamin C, and polyphenols content were also compared with CD obtained powders. The FBJD method combined with CD pre-drying proved superior to just using the CD method, where powders had a greater preservation of vitamin C at 84% (CD powders 35%), a 12% higher total polyphenol content, and a 10% higher antioxidant activity. The test method also uses a much shorter drying time than the CD method, because the grinding of the hard-textured material takes only few minutes.

Functional Tea-Infused Set Yoghurt Development by Evaluation of Sensory Quality and Textural Properties

In the present study, the potential to design natural tea-infused set yoghurt was investigated. Three types of tea (Camellia sinensis): black, green and oolong tea as well as lemon balm (Melissa officinalis L.) were used to produce set yoghurt. The sensory quality (using Quantitative Descriptive Profile analysis and consumer hedonic test) and texture analysis, yield stress, physical stability and colour analysis were assessed to describe the profile of the yoghurt and influence of quality attributes of the product on the consumer acceptability of infused yoghurts in comparison with plain yoghurt. Among the analyzed plant additives for yoghurt, addition of 2% oolong tea to the yoghurt allows a functional food to be obtained with satisfactory texture and sensory properties, accepted by consumers at the same level as for control yoghurt. Both types of yoghurt were also characterised by high consumer willingness to buy, which confirms the legitimacy of using oolong tea as a natural, functional yoghurt additive that improves the sensory quality of the product. The high overall quality of yoghurt with oolong tea in comparison to other plant extracts was associated with the intensive peach flavour and odour, nectar and sweet odour and flavour, and the highest creaminess and thickness. That was confirmed by principal component analysis (PCA) where the overall sensory quality of yoghurts was mainly positively correlated with peach flavour and odour, sweet odour and yoghurt odour, while it was negatively correlated with herbs flavor and odour, and green tea flavour and odour. The sensory profile confirmed no differences in textural profile between plain yoghurt and the tea-infused one measured in the mouth, which corresponds to the result of textural properties such as firmness and adhesiveness.

The in vitro efficacy of eye drops containing a bacteriophage solution specific for Staphylococcus spp. isolated from dogs with bacterial conjunctivitis

BACKGROUND

The purpose of the study was to evaluate the in vitro antibacterial effect of experimental eye drops with bacteriophages in elimination of Staphylococcus spp. isolated from dogs with bacterial conjunctivitis.. The bacterial material was collected from dogs with independent clinical signs of bacterial conjunctivitis. Staphylococcus spp. were identified by phenotypic and genotypic methods (MALDI-TOF MS mass spectrometry). Antibiotic resistance was determined by the disc-diffusion method. Phage activity (Plaque forming units, PFU) was determined on double-layer agar plates. Phages with lytic titres > 10⁸ PFU were used to prepare eye drops. The stability of the antibacterial titre was evaluated for preparations stored in sealed bottles as well as after opening and reclosing.

RESULTS

The tests confirmed the occurrence of Staphylococcus spp. strains as etiological agents of bacterial conjunctivitis in dogs. A high percentage of strains were resistant to more than three antibiotics. The experimental phage eye drops used in the study exhibited 100% efficacy in vitro against the tested Staphylococcus isolates. Particularly noteworthy is the long duration of activity and constant antibacterial lytic titre of ≥10⁸ PFU/mL of two eye drop solutions, nos. 7 and 12, after the bottle had been opened (21 days) and after hermetically sealed packaging (28 days) at 4-8 °C.

CONCLUSIONS

The results represent the first stage of research and require continuation in vivo. If positive effects are obtained in animals, the results can be used in applied research in humans and animals.

Correction to: Long-term vigabatrin treatment modifies pentylenetetrazole-induced seizures in mice: focused on GABA brain concentration

The article Long-term vigabatrin treatment modifies pentylenetetrazole-induced seizures in mice: focused on GABA brain concentration.

Influence of the endocannabinoid system on the antidepressant activity of bupropion and moclobemide in the behavioural tests in mice

Background

Though there are several classes of antidepressant drugs available on the pharmaceutical market, depression that affects globally over 320 million people is still undertreated. Scientists have made attempts to develop novel therapeutical strategies to maximize effectiveness of therapy and minimize undesired reactions. One of the ideas is use of either dual-action agents or combined administration of two substances that affect diverse neurotransmissions. Thus, we investigated whether the selected CB receptor ligands (oleamide, AM251, JWH133, and AM630) can have an impact on the activity of bupropion and moclobemide. Bupropion belongs to the dual acting drugs, whereas moclobemide is an inhibitor of monoamine oxidase.

Methods

The mice forced swim test and the tail suspension test were applied in order to determine the potential antidepressant-like activity, whereas the HPLC method was used in order to assess the brain concentrations of the tested antidepressants.

Results

An intraperitoneal injection of sub-effective doses of oleamide (5 mg/kg), AM251 (0.25 mg/kg), and AM630 (0.25 mg/kg) increased activity of bupropion (10 mg/kg) in both behavioural tests. Effects of moclobemide (1.5 mg/kg) were potentiated only by AM251. These results were not influenced by the hypo- or hyperlocomotion of animals.

Conclusion

The outcomes of the present study revealed that particularly activation or inhibition of the CB₁ receptor function may augment the antidepressant activity of bupropion, whereas only inhibition of the CB₁ receptor function manages to increase activity of moclobemide. Most probably, an interplay between CB receptor ligands and bupropion or moclobemide takes place at the cellular level.

Long-term vigabatrin treatment modifies pentylenetetrazole-induced seizures in mice: focused on GABA brain concentration

BACKGROUND

The goal of our study was to examine the long-term effect of vigabatrin (VGB), a γ-aminobutyric acid aminotransferase (GABA-AT) inhibitor on clonazepam (CLO), ethosuximide (ETX) and valproate (VPA) anticonvulsive activity against pentylenetetrazole (PTZ)-induced seizures in mice.

METHODS

VGB was administered for 3 and 7 days. Convulsions were evoked by PTZ at its CD97 (99 mg/kg). The influence of CLO, ETX and VPA alone or in combination with VGB on motor performance and long-term memory was analyzed. γ-aminobutyric acid (GABA) concentration in mice brain and plasma as well as glutamate decarboxylase (GAD) activity was measured.

RESULTS

After 3 days of treatment, VGB in doses up to 500 mg/kg increased PTZ-induced seizure threshold, whereas after 7 days VGB (at the dose of 125 mg/kg) inhibited clonic seizures in experimental mice. 7 days of VGB administration did not change the protective effect of CLO, ETX and VPA against PTZ-induced seizures. 7 days of VGB treatment at a subthreshold dose of 75 mg/kg decreased TD50 of ETX and CLO in the chimney test, but did not affect TD50 value for VPA. 7 days of VGB administration in combination with AEDs did not affect long-term memory in mice. VGB after 3 days or 7 days of administration increased brain GABA concentration. GAD activity was decreased after 3 and 7 days of VGB administration.

CONCLUSIONS

The presented results confirm anticonvulsive activity of VGB through GABA metabolism alteration and suggest care when combining VGB with ETX or CLO in the therapy.

Influence of salbutamol on the anticonvulsant potency of the antiepileptic drugs in the maximal electroshock-induced seizures in mice

BACKGROUND

β₂-Adrenergic receptor agonists are widely used agents in the treatment of asthma or preterm labor. Since prevalence of asthma was shown to be higher in patients with epilepsy and modulation of noradrenergic system activity may modify epilepsy course, the aim of the present study was to examine the effect of salbutamol (SALB), one of the most commonly used β₂-adrenergic receptor agonist on the anticonvulsant potency of four classical antiepileptic drugs (AEDs): valproate (VPA), carbamazepine (CBZ), phenytoin (DPH) and phenobarbital (PB) in mice subjected to the maximal electroshock (MES)-induced seizures.

METHODS

Seizures were caused by a current delivered through ear-clip electrodes. The influence of AEDs and SALB on animals' motor coordination and memory processes was also evaluated.

RESULTS

Single SALB injection did not change, whereas 7 days SALB administration decreased seizure threshold in the MES-induced seizures in mice. Moreover, SALB injected ip for 1 day and for 7 days lowered the antiepileptic activity of PB in the MES-induced seizures in mice, but did not change the effect of other analyzed AEDs: VPA, CBZ or DPH. Butoxamine, a selective β₂-adrenergic receptor antagonist, reversed SALB influence on the activity of PB. SALB given alone or in combination with the tested AEDs did not affect animals' motor performance and memory after both single and 7 days administration.

CONCLUSIONS

Presented results show that SALB may decrease the antiepileptic efficacy of PB. A special caution is advised to patients with epilepsy receiving β₂-adrenergic receptors agonists in the pharmacotherapy of pulmonary and obstetrical disorders.

Antidepressant-Like Activity of Typical Antidepressant Drugs in the Forced Swim Test and Tail Suspension Test in Mice Is Augmented by DMPX, an Adenosine A2A Receptor Antagonist

Unsatisfactory therapeutic effects of currently used antidepressants force to search for new pharmacological treatment strategies. Recent research points to the relationship between depressive disorders and the adenosinergic system. Therefore, the main goal of our studies was to evaluate the effects of DMPX (3 mg/kg, i.p.), which possesses selectivity for adenosine A_2A receptors versus A₁ receptors, on the activity of imipramine (15 mg/kg, i.p.), escitalopram (2.5 mg/kg, i.p.), and reboxetine (2 mg/kg, i.p.) given in subtherapeutic doses. The studies carried out using the forced swim and tail suspension tests in mice showed that DMPX at a dose of 6 and 12 mg/kg exerts antidepressant-like effect and does not affect the locomotor activity. Co-administration of DMPX at a dose of 3 mg/kg with the studied antidepressant drugs caused the reduction of immobility time in both behavioral tests. The observed effect was not associated with an increase in the locomotor activity. To evaluate whether the observed effects were due to a pharmacokinetic/pharmacodynamic interaction, the levels of the antidepressants in blood and brain were measured using high-performance liquid chromatography. It can be assumed that the interaction between DMPX and imipramine was exclusively pharmacodynamic in nature, whereas an increased antidepressant activity of escitalopram and reboxetine was at least partly related to its pharmacokinetic interaction with DMPX.

DPCPX, a selective adenosine A1 receptor antagonist, enhances the antidepressant-like effects of imipramine, escitalopram, and reboxetine in mice behavioral tests

The main goal of the present study was to evaluate the influence of the adenosine A1 receptor (A1R) antagonist — DPCPX — on depressive-like behavior in mice, as well as the effect of DPCPX on the activity of imipramine, escitalopram, and reboxetine, each at non-effective doses. The influence of DPCPX on behavior and its influence on the activity of selected antidepressants was evaluated in the forced swim test (FST) and the tail suspension test (TST) in mice. Locomotor activity was measured to verify and exclude false-positive data obtained in the FST and TST. Moreover, serum and brain concentrations of tested antidepressants were determined using HPLC. DPCPX, at doses of 2 and 4 mg/kg, exhibited antidepressant activity in the FST and TST, which was not related to changes in the spontaneous locomotor activity. Co-administration of DPCPX with imipramine, escitalopram, or reboxetine, each at non-active doses, significantly reduced the immobilization period in the FST and TST in mice, which was not due to the increase in locomotor activity. Both antagonists of 5-HT receptors (WAY 100635 and ritanserin) completely antagonized the effect elicited by DPCPX in the behavioral tests. Results of assessment of the nature of the interaction between DPCPX and test drugs show that in the case of DPCPX and imipramine or reboxetine, there were pharmacodynamic interactions, whereas the DPCPX-escitalopram interaction is at least partially pharmacokinetic in nature. Presented outcomes indicate that an inhibition of A1Rs and an increase of monoaminergic transduction in the CNS may offer a novel strategy for the development of antidepressant drugs.

The influence of selective A1 and A2A receptor antagonists on the antidepressant-like activity of moclobemide, venlafaxine and bupropion in mice

Objective

The main goal of our study was to investigate whether a selective antagonism of the adenosine A1 or A2A receptors is able to enhance the antidepressant activity of commonly prescribed drugs.

Materials and methods

All experiments were carried out on male Albino Swiss mice. The forced swim test and the tail suspension test were used to evaluate the antidepressant-like potential. Drug concentrations in animals’ serum and brains were measured by high-performance liquid chromatography.

Key findings

The antidepressant potential of moclobemide (1.5 mg/kg), venlafaxine (1 mg/kg) and bupropion (10 mg/kg) was enhanced by a co-administration with 3,7-dimethyl-1-propargylxanthine (DMPX; an antagonist of adenosine A2A receptors; 3 mg/kg) or 8-cyclopentyl-1,3-dipropylxanthine (an antagonist of adenosine A1 receptors; 1 mg/kg). However, significant interactions between the tested substances were detected only in the experiments with DMPX. The nature of the observed interplays is rather pharmacodynamic than pharmacokinetic, because neither serum nor brain concentrations of the used drugs were significantly increased.

Conclusions

Blockage of the adenosine receptors (particularly the A2A subtypes) could be considered in future as a novel, promising part of the combined antidepressant therapy. However, further studies on this subject are needed.

Withdrawal of caffeine after its chronic administration modifies the antidepressant-like activity of atypical antidepressants in mice. Changes in cortical expression of Comt, Slc6a15 and Adora1 genes

RATIONALE

Depressed patients often present increased consumption of caffeine.

OBJECTIVES

We aimed to investigate the effects of chronic treatment with caffeine (5 mg/kg, twice daily for 14 days) on the activity of single, ineffective doses of agomelatine (20 mg/kg) or mianserin (10 mg/kg) given on day 15 alone or simultaneously with caffeine.

METHODS

We used the forced swim test (FST), tail suspension test (TST), and locomotor activity test in mice and quantitative real-time PCR analysis of the selected genes in the cerebral cortex (Cx).

RESULTS

There were no changes in the immobility time between mice that received saline and caffeine for 14 days. Administration of agomelatine or mianserin on day 15 did not produce an antidepressant-like effect, but such effect was observed after administration of agomelatine or mianserin simultaneously with caffeine on day 15, in both mice that received saline and caffeine for 14 days. In mice treated with caffeine for 14 days, joint administration of agomelatine or mianserin and caffeine on day 15 decreased solute carrier family 6, member 15 (Slc6a15), messenger RNA (mRNA) level in the Cx, compared to the group which received only the respective antidepressant on this day. Moreover, in mice treated with caffeine for 14 days, joint administration of mianserin and caffeine on day 15 decreased adenosine A1 receptor (Adora1) and catechol-O-methyltransferase (Comt) mRNA level in the Cx, compared to the group which received mianserin without caffeine on this day.

CONCLUSIONS

Withdrawal of caffeine after its chronic intake can modify the activity of antidepressants. Adora1, Slc6a15, and Comt may be involved in the antidepressant-like effect observed after joint administration of caffeine and mianserin or agomelatine, following chronic treatment with caffeine.

Effect of boar ejaculate fraction, extender type and time of storage on quality of spermatozoa

The aim of this study was to investigate the effect the sperm-rich fraction (F1) and the post-F1 fraction (F2) on the quality of boar spermatozoa stored in a liquid state. Ejaculates were collected from three Polish Landrace boars. Each ejaculate fraction was diluted with BTS short-term extender and Safe-Cell Plus (SCP) long-term extender and stored for seven days (D1-D7) at 17°C. Analyses included sperm motility parameters, normal apical ridge (NAR) acrosomes and plasma membrane integrity (PMI). Prior to the dilution of fractions, marked changes (p<0.05) were noted between F1 and F2 in progressive motility (PMOT), velocity average pathway (VAP) and velocity straight line (VCL). After the ejaculate was diluted, the type of fraction and type of extender significantly affected (p<0.05) PMOT, being markedly higher (p<0.05) for F1 extended in BTS. No marked changes (p<0.05) were observed between F1 and F2 extended in SCP for any of the analyzed sperm quality parameters during seven days of storage. Significantly higher (p<0.05) values of sperm quality parameters were noted in F1 compared with F2 for BTS on D7 of storage. The results of the four-way ANOVA analysis indicate that boar, fraction of ejaculate, extender type and day of storage had significant effects on the quality of boar stored spermatozoa. The F1 was characterised by higher quality of spermatozoa during storage in comparison with F2 in the short-term extender. Using the long-term extender containing the proteins allowed for a better application of F2, which could be important for the pig industry.

Comparison of physicochemical properties of suppositories containing starch hydrolysates

The purpose of this work was to determine the effect of starch hydrolysates (SH) on the physicochemical properties of suppositories. The study was conducted with suppositories with acetaminophen (AAP) a typical antipyretic analgesic, as model drug on lipophilic (cocoa butter) and hydrophilic base (polyethylene glycol 1500 + 400). The suppositories with and without the addition of SH were examined for physicochemical tests according to European Pharmacopoeia 8th edition (Ph. Eur.): the uniformity of mass of single-dose preparation test, the softening time determination of lipophilic suppositories test, the disintegration of suppositories test, and dissolution test with flow-through apparatus. The results confirm the possibility of using starch hydrolysates as a cheap and safe addition to modify physicochemical properties of suppositories.

Assessing polyphenols content and antioxidant activity in coffee beans according to origin and the degree of roasting

BACKGROUND

The roasting stage constitutes a key component in the manufacturing process of natural coffee because temperature elicits changes in bioactive compounds such as polyphenols and that Maillard-reaction compounds appear, thus affecting the product’s sensory and antioxidant properties. Actual contents of these compounds may depend on which region the coffee is cultivated as well as the extent to which the beans are roasted

OBJECTIVES

To determine polyphenols content and antioxidant activity in the ‘Arabica’ coffee type coming from various world regions of its cultivation and which have undergone industrial roasting. Also to establish which coffee, taking into account the degree of roasting (ie. light, medium and strong), is nutritionally the most beneficial

MATERIALS AND METHODS

The study material was natural coffee beans (100% Arabica) roasted to various degrees, as aforementioned, that had been cultivated in Brazil, Ethiopia, Columbia and India. Polyphenols were measured in the coffee beans by spectrophotometric means based on the Folin-Ciocalteu reaction, whereas antioxidant activity was measured colourimetrically using ABTS+ cat-ionic radicals

RESULTS

Polyphenol content and antioxidant activity were found to depend both on the coffee’s origin and degree of roasting. Longer roasting times resulted in greater polyphenol degradation. The highest polyphenol concentrations were found in lightly roasted coffee, ranging 39.27 to 43.0 mg/g, whereas levels in medium and strongly roasted coffee respectively ranged 34.06 to 38.43 mg/g and 29.21 to 36.89 mg/g. Antioxidant activity however significantly rose with the degree of roasting, where strongly roasted coffee had higher such activity than lightly roasted coffee. This can be explained by the formation of Maillard-reaction compounds during roasting, leading then to the formation of antioxidant melanoidin compounds which, to a large extent, compensate for the decrease in polyphenols during roasting

CONCLUSIONS

Polyphenols levels and antioxidant activities in the studied Arabica coffee beans that had undergone roasting depended on the cultivation region of the world. Longer roasting caused a significant decline in polyphenols compound levels (from 7.3% to 32.1%) in the coffee beans. Antioxidant activities of coffee increased with roasting, despite reduced levels of natural antioxidants. From a nutritional standpoint, the most favoured coffees are those lightly or medium roasted

Influence of the selective antagonist of the NR2B subunit of the NMDA receptor, traxoprodil, on the antidepressant-like activity of desipramine, paroxetine, milnacipran, and bupropion in mice

Pre-clinical and clinical studies indicated that a blockade of the NMDA receptor complex creates new opportunities for the treatment of affective disorders, including depression. The aim of the present study was to assess the influence of traxoprodil (10 mg/kg) on the activity of desipramine (10 mg/kg), paroxetine (0.5 mg/kg), milnacipran (1.25 mg/kg), and bupropion (10 mg/kg), each at sub-therapeutic doses. Moreover, brain levels of traxoprodil and tested agents were determined using HPLC. The obtained results were used to ascertain the nature of occurring interaction between traxoprodil and studied antidepressants. The experiment was carried out on naïve adult male Albino Swiss mice. Traxoprodil and other tested drugs were administered intraperitoneally. The influence of traxoprodil on the activity of selected antidepressants was evaluated in forced swim test (FST). Locomotor activity was estimated to exclude false positive/negative data. To assess the influence of traxoprodil on the concentration of used antidepressants, their levels were determined in murine brains using HPLC. Results indicated that traxoprodil potentiated activity of all antidepressants examined in FST and the observed effects were not due to the increase in locomotor activity. Only in the case of co-administration of traxoprodil and bupropion, increased bupropion concentrations in brain tissue were observed. All tested agents increased the traxoprodil levels in the brain. Administration of a sub-active dose of traxoprodil with antidepressants from different chemical groups, which act via enhancing monoaminergic transduction, caused the antidepressant-like effect in FST in mice. The interactions of traxoprodil with desipramine, paroxetine, milnacipran, and bupropion occur, at least partially, in the pharmacokinetic phase.

Traxoprodil, a selective antagonist of the NR2B subunit of the NMDA receptor, potentiates the antidepressant-like effects of certain antidepressant drugs in the forced swim test in mice

One of the newest substances, whose antidepressant activity was shown is traxoprodil, which is a selective antagonist of the NR2B subunit of the NMDA receptor. The main goal of the present study was to evaluate the effect of traxoprodil on animals' behavior using the forced swim test (FST), as well as the effect of traxoprodil (10 mg/kg) on the activity of antidepressants, such as imipramine (15 mg/kg), fluoxetine (5 mg/kg), escitalopram (2 mg/kg) and reboxetine (2.5 mg/kg). Serotonergic lesion and experiment using the selective agonists of serotonin receptors 5-HT1A and 5-HT2 was conducted to evaluate the role of the serotonergic system in the antidepressant action of traxoprodil. Brain concentrations of tested agents were determined using HPLC. The results showed that traxoprodil at a dose of 20 and 40 mg/kg exhibited antidepressant activity in the FST and it was not related to changes in animals' locomotor activity. Co-administration of traxoprodil with imipramine, fluoxetine or escitalopram, each in subtherapeutic doses, significantly affected the animals' behavior in the FST and, what is important, these changes were not due to the severity of locomotor activity. The observed effect of traxoprodil is only partially associated with serotonergic system and is independent of the effect on the 5-HT1A and 5-HT2 serotonin receptors. The results of an attempt to assess the nature of the interaction between traxoprodil and the tested drugs show that in the case of joint administration of traxoprodil and fluoxetine, imipramine or escitalopram, there were interactions in the pharmacokinetic phase.

The effects of cimetidine chronic treatment on conventional antiepileptic drugs in mice

PURPOSE

The aim of this study was to evaluate the effects of 1-day, 7-day and 14-day administrations of cimetidine on the anticonvulsant activity of conventional antiepileptic drugs (AEDs; valproate, carbamazepine, phenytoin and phenobarbital) against maximal electroshock (MES)-induced convulsions in mice.

METHODS

Electroconvulsions were evoked in Albino Swiss mice by a current delivered via ear-clip electrodes. In addition, the effects of cimetidine, AEDs alone and their combinations were studied on performance and long-term memory tests. Pharmacokinetic changes in plasma and brain concentrations of AEDs after cimetidine administration were evaluated with immunofluorescence.

RESULTS

Cimetidine (up to 100mg/kg) after 1-day administration did not affect the electroconvulsive threshold in animals. Moreover, in the 14-day treatment, cimetidine administered at a dose of 40mg/kg did not significantly change the electroconvulsive threshold in the MES-test, cimetidine administered 14-day (at 20mg/kg) significantly increased the anticonvulsant activity of carbamazepine, staying without effects after a 1-day and 7-day studies. In contrast, both the 7-day and 14-day administrations of cimetidine resulted in significant reductions of protective efficacy of the phenobarbital. Only valproate and phenytoin were not affected by cimetidine (20mg/kg) in all experimental period. Cimetidine administered 1-day, did not alter total brain concentrations and free plasma levels of all AEDs tested, whilst the 14-day study elevated carbamazepine plasma and brain concentration and reduced phenobarbital brain concentration. Cimetidine co-applied with AEDs did not impair performance of mice evaluated in the chimney test however, it worsened long-term memory in animals.

CONCLUSIONS

Based on this preclinical study, a special caution is advised when treating epileptic patients with combinations of phenobarbital or carbamazepine with cimetidine.

EFFECT OF STARCH HYDROLYSATES IN THE PROCESS OF DISSOLUTION OF SOLIDS

The purpose of this work was to investigate the influence of starch hydrolysates in the dissolution process of the substance practically insoluble in water. Progesterone and ibuprofen were chosen as model substances. The study was conducted with a constant amount of the drug (25 mg/mL) or constant amount of starch hydrolysate (50 mg/mL). Next, the influence of ethanolic solutions (10-30% v/v) on solubility of drug was tested. The results confirm the possibility of using starch hydrolysate as a cheap and safe addition to increase the solubility of practically insoluble drugs.