Involvement of the serotoninergic system in the anxiolytic action mechanism of a liposomal formulation containing nimodipine (NMD-Lipo)

In the search for anxiolytic drugs with fewer adverse effects, calcium blockers were proposed as a benzodiazepines (BZDs) alternative. In this context, the anxiolytic effect of nimodipine has been demonstrated. However, its low bioavailability and solubility could be improved by using nanostructured drug delivery systems such as liposomes. In this way, liposomal formulation containing nimodipine (NMD-Lipo) was developed. The NMD-lipo is a formulation capable of improving the kinetic characteristics of the drug, as well as the anxiolytic effect of nimodipine. In this work, the serotonergic system participation in the anxiolytic mechanism of the liposomal formulation containing nimodipine (NMD-Lipo) was investigated. A possible 5-HT1A receptor mediation on the NMD-Lipo anxiolytic effect was demonstrated by using WAY 100635 (5-HT1A receptor antagonist) since the antagonist reversed the NMD-Lipo anxiolytic effect in the light/dark test and elevated plus maze test. The results demonstrated that the NMD-Lipo administration had anxiolytic activity through 5-HT1A receptors without causing sedation or compromising the motor coordination of the tested animals.

Cytotoxic and Antioxidant Properties of Natural Bioactive Monoterpenes Nerol, Estragole, and 3,7-Dimethyl-1-Octanol

The therapeutic potential of medicinal plants is noted because of the presence of varieties of biochemicals. The monoterpenes, like nerol, estragole, and 3,7-dimethyl-1-octanol, have been reported for antimicrobial, antifungal, anthelmintic, and antioxidant activities. This study evaluated the toxic, cytotoxic, and oxidant/antioxidant effects of these compounds by several in vitro (DPPH and ABTS radical scavenging, and ferric reducing potential), ex vivo (hemolysis), and in vivo (Artemia Salina and Saccharomyces cerevisiae) assays. Results suggest that estragole and 3,7-dimethyl-1-octanol at 31.25-500 μg/mL did not exhibit significant cytotoxic effects in the A. Salina and hemolysis tests. Nerol showed significant cytotoxic effects on these test systems at all test concentrations. The monoterpenes showed radical (ABTS•+ and DPPH•) scavenging capacities in a concentration-dependent manner in vitro tests. However, they did not oxidize the genetic material of S. cerevisiae (SODWT, Sod1Δ, Sod2Δ, Sod1/Sod2Δ, Cat1Δ, and Cat1Δ/Sod1Δ) lines. Among the three monoterpenes, nerol may be a good candidate for antioxidant and anti-tumor therapies.

Evaluation of the non-clinical toxicity of an antiparasitic agent: diminazene aceturate

The diminazene aceturate (C₁₄H₁₅N₇.2C₄H₇NO₃) is a chemotherapeutic agent with more than six decades of use, however more studies regarding its toxicity still need to be performed. Thus, the present study determined the acute toxicity (14 days) of diminazene acetate (DIZE) in male and female swiss mice by changes in body mass, food consumption, biochemical and hematological parameters, locomotor activity and motor coordination. DIZE was administered at a single dose (1000 and 2000 mg/kg) orally. In addition, in vitro antioxidant capacity, hemolytic activity, toxicity in Artemia salina and in silico evaluation were also performed. The results obtained include several signs of toxicity (hypoactivity, loss of the straightening reflex and tachycardia), reduction of behavioral activity (locomotor activity and motor coordination) and significant changes (p < 0.05) in biochemical and hematological parameters. According to the in silico study, the DIZE can be classified based on the mean lethal dose (LD₅₀) in category 4 (300 mg/kg < LD₅₀ ≤ 2000 mg/kg, ProTox-II) or 3 (50 mg/kg < LD₅₀ ≤ 300 mg/kg, AdmetSAR 1.0). Additionally, DIZE (30.3-969.9 nM) was not toxic to A. salina in the first 48 hours of treatment and was not cytotoxic to rat red blood cells after induced hemolysis. In vitro results indicated low antioxidant capacity against DPPH^• and ABTS^•+ radicals. Therefore, DIZE induces several adverse effects with influence on the central nervous system, changes in hematological and biochemical parameters and even mortality at the highest dose. However, absence of toxicity was observed in A. salina and rats red blood cells.

Cytogenotoxic and mutagenic profiling of cashew nut shell liquids and cardanol

Background

Cashew and its compounds have many important biological effects. This study is aimed at evaluating genotoxic and mutagenic effects of natural cashew nut shell liquid (nCNSL) and industrial cashew nut shell liquid (iCNSL) and a major component of iCNSL called Cardanol.

Methods

Test samples were undergone for comet assay and micronucleus tests inSwissalbino mice. Animals were orally treated with 17.37, 34.75 and 69.5 mg/kg of the test substances taking distilled water (10 mL/kg; DW) and cyclophosphamide (50 mg/kg) as negative (NC) and positive (PC) controls, respectively.

Results

The results suggest that nCNSL at 34.7 and 69.5 mg/kg and Cardanol at all tested doses induced significant genotoxic effects to the female mouse bone marrow cells, while iCNSL did not. Both nCNSL and iCNSL as well as Cardanol did not show mutagenic and cytotoxic effects. All the test samples also showed DNA repair capacity at low dose.

Conclusion

Cashew nut shell liquids and Cardanol showed genotoxic effects at high dose, but DNA repair, non-mutagenic and non-cytotoxic effects at low dose.

Correction to: Cytogenotoxic and mutagenic profiling of cashew nut shell liquids and cardanol

In the original publication of this article [1], one author’s name needs to be revised from Ana Ana Amélia de Carvalho Melo-Cavalcante to Ana Amélia de Carvalho Melo-Cavalcante.

Determination of Parameters of Oxidative Stress in vitro Models of Neurodegenerative Diseases-A Review

Oxidative stress is a major mechanism underlying the development of various neurodegenerative diseases (Alzheimer, Parkinson, Huntington and amyotrophic lateral sclerosis). Excessive formation of reactive oxygen species (ROS) and nitrogen (RNSs) can overburden the ability of the enzymatic antioxidant defense mechanisms (superoxide dismutase, catalase and glutathione reductase) and non-enzymatic (uric acid, ascorbic acid, α-tocopherol and reduced glutathione), causing the development of oxidative stress, and consequently, impairing the neuronal system cells by means of oxidative damage to a variety of important biological molecules such as lipids, DNA and proteins. Considering the importance of oxidative stress in neurodegenerative diseases, the present review aims to address the main parameters evaluated in in vitro studies on oxidative stress in different models of neurodegenerative diseases.The literary review was conducted through Pubmed, Science Direct, LILACS, Scielo and Google using following keywords: oxidative stress, neurodegenerative diseases and parameters of oxidative stress. We selected articles published between 2002 and 2017.The in vitro evaluation of the oxidative stress related parameters has provided a preliminary view about the pathogenesis of many neurodegenerative diseases (Alzheimer's, Parkinson's, Huntington's and Amyotrophic lateral sclerosis). In this way, it has demonstrated the mechanism of action of ROS/RNSs in these diseases by direct or indirect detection through several experimental procedures in vitro.

Neurochemical properties of neurospheres infusion in experimental-induced seizures

Cell replacement through neural stem cells has been a promising alternative therapy for neurodegenerative diseases. It was evaluated the possible protect and/or prevent role of neurospheres in experimental models of epilepsy by the use of biomarkers of oxidative stress and histopathological analysis. After 1 h of the epileptic inductions by pilocarpine, pentylenotetrazole and picrotoxin, rats were infused with a suspension of 2 × 10⁶ cells/0.25 mL, marked with Qtracker® 655, via caudal vein. In the control group epilepsy was not induced, but received the cell infusion under the same conditions of other groups. After 30 days, the rats were euthanized, and the removal of the brain was proceeded to later perform the assays oxidative stress and histopathology analysis. Thiobarbituric acid and nitrite levels were elevated in epileptic groups treated with neurospheres, and the levels of reduced glutathione, superoxide dismutase and catalase were reduced when compared to non-treated groups. The performance of oxidative enzymes from pilocarpine group treated with neurospheres showed slight increase. Histopathological evaluation observed distribution of neurospheres throughout the brain tissue, with viable cells and in process of differentiation in the pilocarpine group, but with differentiation and regeneration compromised in epilepsy by picrotoxin and pentylenetetrazole due to a microenvironment of oxidative stress. Neural stem cell therapy has a promising potential for protection in the pilocarpine epilepsy model, suggesting that the antioxidant system of neurospheres could reduce oxidative damage generated by seizure.

In Vitro and Ex Vivo Chemopreventive Action of Mauritia flexuosa Products

Mauritia flexuosa (Arecaceae), known as "Buriti," is a Brazilian palm tree with high economic potential for local communities. Herein, we investigated the phytochemistry profile and antioxidant potential of M. flexuosa fruits and determined the bioaccessibility of phenolic compounds. Peels revealed upper values for phenols, flavonoids, carotenoids, tannins, and ascorbic acid when compared to the pulps and endocarps. All samples showed capacity to scavenger free radicals (0.5, 1.0, 2.0, 4.0, and 8.0 mg/mL) but peels presented higher scavenger action in all methods explored. Phenolic compounds identified by HPLC displayed reduced bioaccessibility after in vitro simulated gastrointestinal digestion for pulp (38.7%), peel (18.7%), and endocarp (22.3%) extracts (P < 0.05). Buriti fruits also protected rat blood cells against lysis induced by peroxyl radicals. We demonstrated the promising chemopreventive potentialities of M. flexuosa fruits and their by-products and peels with higher quantities of bioactive compounds and phenolic substances before and after in vitro bioaccessibility investigation. In Brazil, these parts are discarded or underused, mainly as feed for ruminant animals. Consequently, it is extremely important to explore nutritional characteristics of these by-products for human/livestock foods and to install biofriendly techniques and sustainable biotechnology handling of natural resources.

Phytochemistry Profile, Nutritional Properties and Pharmacological Activities of Mauritia flexuosa

Mauritia flexuosa L. (Arecaceae) is a popular Brazilian fruit known as "buriti" and belonging to the category of functional foods. This work reviewed the phytochemistry profile, nutritional and pharmacological activities of M. flexuosa. The main bioactive compounds reported to buriti were carotenoids, tocopherols, ascorbic acid, phenolic compounds, fiber, phytosterols, and mono- and poly-unsaturated fatty acids. These compounds were mainly related to antioxidant, hypolipemiant, photoprotector, antiaggregant, antithrombotic, anti-inflammatory, hypoglycemiant, antimicrobial, and antitumor activities. Furthermore, some compounds present in buriti fruit and its properties were tested in vitro and in vivo and showed biotechnology applications, especially for extraction of fiber, polysaccharides, pigments, antioxidants, and oil. Howerer, the buriti fruit shows great relevance to the development of new products in food, pharmaceutical and chemical industry, this fruit is still underexploited and it has need to expand its production chain and processing to encourage their consumption and utilization.

Pre-clinical toxicology of garcinielliptone FC, a tautomeric pair of polyprenylated benzophenone, isolated from Platonia insignis Mart seeds

BACKGROUND

Garcinielliptone FC (GFC) is a tautomeric pair of polyprenylated benzophenone, which has proven to have antiepileptic, cytotoxic and antioxidant activity.

PURPOSE

The aim of this study was to investigate the biochemical, hematological and pathological effects of the acute toxicity study as well as to assess the locomotor activity and motor coordination in mice treated with GFC.

METHODS

Swiss mice of both sexes weighing 25-30 g divided into three separate groups of five animals matched by weight and size. GFC was aseptically suspended in 0.05% Tween 80, dissolved in 0.9% saline (vehicle) and administered orally (p.o.) and intraperitoneally (i.p.) (500, 1000 and 2000 mg/kg). The acute toxicity study was performed in compliance with the Anvisa regulations.

RESULTS

Behavioral manifestations of toxicity, such as state of consciousness, coordination, muscle tone, reflexes, the activity on the central nervous system (shake, seizures, Straub tail reaction and anesthesia) and the activity of the autonomic nervous system (lacrimation, ptosis, urination, piloerection, hypothermia, breathing and hyperemia) were not seen in any of the animals treated with doses of 500, 1000 and 2000 mg/kg. Additionally, no significant difference in body weight, food and water intake, excreta production or macroscopic changes in the organs of treated animals were detected in comparison with control group. GFC did not affect the locomotor activity and motor coordination of the animals.

CONCLUSION

The acute toxicity study indicated that GFC treatment, at selected doses given orally and intraperitoneally, showed relatively low risk of toxicity in all test animals, suggesting that it is safe for further investigation.