Correlations between the degree of infection by wild strain of Toxoplasma gondii in vitro and porcine hematological parameters.

The apicomplexa Toxoplasma gondii is capable of actively proliferating in numerous types of nucleated cells, and therefore has a high potential for dissemination and resistance. Thus, the present work aimed to correlate the inoculum concentrations and amount of post-infection parasites with porcine hematological parameters (including biochemistry) through in vitro culture. Porcine blood was incubated with different concentrations of parasites (1.2 × 107, 6/3/1.5 × 106 cells/mL), then the concentrations of red blood cells (RBC) and their morphology, total and differential leukocytes, and free peptides were evaluated. In addition, eight different blood samples analyzed before inoculation, where subsequent multivariate analysis was applied to correlate different variables with trophozoite concentration. The results showed no significant variation (p < 0.05) in the relative levels of free peptides, or the relative percentage of RBC at all the parasite concentrations tested. However, the normalized percentages of leukocytes and neutrophils showed a significant reduction, while those of lymphocytes, eosinophils and monocytes showed the opposite behavior. Semi-automatic processing of images exhibited significant microcytosis and hypochromia. The multivariate analysis revealed a positive correlation between the amount number of protozoa (AP) and the variables: "Red cells" and "Neutrophils", an indifference between the AP and the content of free peptides, and the concentration of monocytes in the samples; and a negative correlation for AP and the percentages of lymphocytes and eosinophils. Our results suggest that specific changes in hematological parameters may be associated with different degrees of parasitemia, demanding a thorough diagnostic process and adequate treatment.

The silver jubilee of the Nitric Oxide journal: From 1997 to 2021.

Based on the Scopus record, Nitric Oxide journal (NOJ) has completed 25 years of publications. On March 8, 2022, the publication data was retrieved from the Scopus database and analyzed on VOSviewer and R-Studio (Bibliometrix R package/Biblioshiny). NOJ has published 1928 research documents majorly comprising of articles (1611/83.56%) and reviews (210/10.89%). The total citations and h-index were 56291 & 97, respectively. The per year (from 1997 to 2022) publications and citations are presented in this study. We tried to highlight some of the influential researchers, institutes, and countries. In all publications, 7450 authors have contributed with a collaboration index of 0.241. For all authors, we provided descriptive details about their total number of publications (NoP), total citations (TC), h-index, g-index, m-index, citations per paper (CPP), citation per year (CPY), HG Sqrt and Q2Index. Based on each indicator, we highlighted the top five scientists. The research publications (over time) of the top ten authors are also described. Furthermore, the collaboration network of authors is graphically presented. We also provided descriptive details about the most productive institutes. The highest number of documents are published by the University of Sao Paolo (n = 78), Brazil, while in-country sections, USA has the highest number of publications (n = 553) with 21739 citations and 69 h-index. In the same vein, for each era (five years) details about the top five countries are provided. In all publications (n = 1794), 34 European, 3 North American, 13 Asian, 10 South American, 5 Middle East, 8 African and 2 Asia Pacific countries have contributed. Numerical details about the collaboration links of all countries and the per-era contributions of the top ten countries are also provided. Based on the co-words analysis the per era research focus is graphically presented. Descriptive details about the major trends in publication in each era are also provided. We also manually analyzed 160 words that appeared more than thirty thousand (n = 30,000) times and tried to provide a broader overview of research publications. Based on Scopus record, the NOJ ranking is yearly improving and presently (2021-2022) it holds 14th and 17th positions in clinical biochemistry and physiology. The success could be attributed to all researchers, institutes, editors-in-chief, reviewers, editorial board & entire management.

Toxicological assessment of a bioactive extract from Triplaris gardneriana Wedd. seeds using alternative models.

The Triplaris gardneriana Wedd. seeds extract has great therapeutic potential due to numerous biological activities such as antioxidant, antibacterial and anti-inflammatory, which are associated with phenolic content. Although this herbal preparation has shown many benefits, recently their toxicity profile has begun to be explored. In this present study, the toxic effects of T. gardneriana seeds ethanolic extract (EETg) on biological systems of different taxonomical groups and levels of complexity (from cell culture to lower vertebrates) were assessed, through a variety of viability and toxicological assays. It was found that EETg did not impair the Saccharomyces cerevisiae growth at the highest tested concentration (200 µg/mL), and no toxicant evidence was observed in Aedes aegypti larvae or in Drosophila melanogaster adult stage. Contrarily, the extract reduced the viability of undifferentiated Caco-2 cells (250 µg/mL, 40% of viable cells), but did not affect differentiated ones. The embryotoxicity in Danio rerio model showed a LC50 of 7.41 mg/L (95% confidence interval, 4.78 - 11.49 mg/L). EETg did not show signs of toxicity in the majority of the models used, but lethality and malformations in zebrafish embryos occurred. Further analyses are needed to better understand the selective toxicity mechanism of EETg on zebrafish, as well as whether the toxic effects happen in higher vertebrates.

A Potential New Source of Therapeutic Agents for the Treatment of Mucocutaneous Leishmaniasis: The Essential Oil of Rhaphiodon echinus.

Weeds are an important source of natural products; with promising biological activity. This study investigated the anti-kinetoplastida potential (in vitro) to evaluate the cytotoxicity (in vitro) and antioxidant capacity of the essential oil of Rhaphiodon echinus (EORe), which is an infesting plant species. The essential oil was analyzed by GC/MS. The antioxidant capacity was evaluated by reduction of the DPPH radical and Fe3+ ion. The clone Trypanosoma cruzi CL-B5 was used to search for anti-epimastigote activity. Antileishmanial activity was determined using promastigotes of Leishmania braziliensis (MHOM/CW/88/UA301). NCTC 929 fibroblasts were used for the cytotoxicity test. The results showed that the main constituent of the essential oil was γ-elemene. No relevant effect was observed concerning the ability to reduce the DPPH radical; only at the concentration of 480 µg/mL did the essential oil demonstrate a high reduction of Fe3+ power. The oil was active against L. brasiliensis promastigotes; but not against the epimastigote form of T. cruzi. Cytotoxicity for mammalian cells was low at the active concentration capable of killing more than 70% of promastigote forms. The results revealed that the essential oil of R. echinus showed activity against L. brasiliensis; positioning itself as a promising agent for antileishmanial therapies.

Metabolic aspects of phenolic compounds from Triplaris gardneriana seeds in the management of oxidative stress.

Objective: Considering the limited number of studies that analyze the behavior of plant preparations in human body, this study aimed to characterize the phenolic compounds from Triplaris gardneriana extract (EETg) in terms of antioxidant and metabolic aspects, integrating in vitro, in silico and in vivo strategies.Methods: EETg was analyzed in relation to polyphenols release from the plant matrix under in vitro digestion, as well as the pharmacokinetic prediction of their major compounds by in silico simulation and understanding of its in vivo antioxidant effect in an alternative animal model.Results: About 35.22% of polyphenols from EETg proved to be accessible after enzymatic hydrolysis. A kinetics study showed that 40% of the total content of these phytochemicals was released from the extract accompanied by increased antioxidant capacity after 180 min of gastrointestinal simulation. A computational approach revealed that 7 out of 9 major phenolic compounds of EETg showed good pharmacokinetic parameters such as intestinal absorption and bioavailability score. In addition, the extract showed a protective effect on copper-induced oxidative stress in Drosophila melanogaster, evidenced by the restoration of basal levels of thiol and malondialdehyde contents. These biochemical observations were supported by the examination of histological features of D. melanogaster brain.Conclusion: It was demonstrated that the oral administration of EETg would provide phenolic compounds partially absorbable by the human gut and capable of providing health benefits associated with the inhibition of oxidative stress. Additionally, the results highlight the need to implement new approaches for the rational development of plant-based medicines.

Acute oral toxicity and antioxidant studies of an amine-based diselenide.

BACKGROUND: Organochalcogen compounds have attracted the interest of a multitude of studies for their promising Pharmacological and biological activities. The antioxidant activity and acute toxicity of an organoselenium compound, 1-(2-(2-(2-(1-aminoethyl)phenyl)diselanyl)phenyl)ethanamine (APDP) was determined in mice. METHODS: Mice were randomly divided into four groups, with each group comprising of seven animals. Canola oil (1ml/kg of body weight) was administered to 1st group, while 2nd, 3rd & 4th groups were administered with 10 mg/kg, 30 mg/kg & 350 mg/kg of APDP respectively. APDP was administered by Intragastric gavage as a single oral dose. RESULTS: The APDP oral administration was found to be safe up to 350 mg/kg of body weight and no deaths of animals were recorded. The lethal dose 50 (LD50) for APDP was determined at 72 h and was estimated to be > 350 mg/kg. After acute treatment, all mice were sacrificed by decapitation to determine the antioxidant enzymes and lipid peroxidation values for the treated mice liver. No fluctuation in lipid peroxidation, vitamin C and non protein thiol (NPSH) levels was observed due to the administration of APDP. hepatic α-ALA-D activity, catalase (CAT), superoxide dismutase (SOD) and the biochemical parameters were evaluated. Experimental observation demonstrated that APDP protected Fe(II) induced thiobarbituric acid reactive substances (TBARS) production in liver homogenate significantly (p < 0.05). The administration of APDP (an amine-based diselenide) both in vitro and in vivo clearly demonstrated that this potential compound has no acute toxicity towards mice among all the tested parameter. CONCLUSION: On the basis of experimental results, it is concluded that APDP is a potential candidate as an antioxidant compound for studying pharmacological properties.

Possible involvement of transcriptional activation of nuclear factor erythroid 2-related factor 2 (Nrf2) in the protective effect of caffeic acid on paraquat-induced oxidative damage in Drosophila melanogaster.

Paraquat (PQ) is a widely used herbicide with no antidote which is implicated in the pathogenesis of the Parkinson's disease. The present study then investigated the potential of caffeic acid (CA), a known antioxidant, cardioprotective and neuroprotective molecule to counteract oxidative stress mediated by PQ. In addition, molecular docking was performed to understand the mechanism underlying the inhibitory effect of CA against PQ poisoning. The fruit fly, Drosophila melanogaster, was exposed to PQ (0.44 mg/g of diet) in the absence or presence of CA (0.25, 0.5, 1 and 2 mg/g of died) for 7 days. Data showed that PQ-fed flies had higher incidence of mortality which was associated with mitochondrial dysfunction, increased free Fe(II) content and lipid peroxidation when compared to the control. Co-exposure with CA reduced mortality and markedly attenuated biochemical changes induced by PQ. The mechanism investigated using molecular docking revealed a strong interaction (-6.2 Kcal/mol) of CA with D. melanogaster transcriptional activation of nuclear factor erythroid 2-related factor 2 (Nrf2). This was characterized by the binding of CA to keap-1 domain of Nrf2. Taking together these results indicate the protective effect of CA against PQ-induced oxidative damage in D. melanogaster was likely through its coordination which hinders Nrf2-keap-1 binding leading to an increase of the antioxidant defense system.

Productivity of CNPq Researchers from Different Fields in Biomedical Sciences: The Need for Objective Bibliometric Parameters-A Report from Brazil.

In Brazil, the CNPq (National Council for Scientific and Technological Development) provides grants, funds and fellowships to productive scientists to support their investigations. They are ranked and categorized into four hierarchical levels ranging from PQ 1A (the highest) to PQ 1D (the lowest). Few studies, however, report and analyse scientific productivity in different sub-fields of Biomedical Sciences (BS), e.g., Biochemistry, Pharmacology, Biophysics and Physiology. In fact, systematic comparisons of productivity among the PQ 1 categories within the above sub-fields are lacking in the literature. Here, the scientific productivity of 323 investigators receiving PQ 1 fellowships (A to D levels) in these sub-fields of BS was investigated. The Scopus database was used to compile the total number of articles, citations, h-index values and authorship positions (first-, co- or last-listed author) in the most cited papers by researchers granted CNPq fellowships. We found that researchers from Pharmacology had the best performance for all of the parameters analysed, followed by those in Biochemistry. There was great variability in scientific productivity within the PQ 1A level in all of the sub-fields of BS, but not within the other levels (1B, 1C and 1D). Analysis of the most cited papers of PQ 1(A-D) researchers in Pharmacology revealed that the citations of researchers in the 1C and 1D levels were associated with publications with their senior supervisors, whereas those in the 1B level were less connected with their supervisors in comparison to those in 1A. Taken together, these findings suggest that the scientific performance of PQ 1A researchers in BS is not homogenous. In our opinion, parameters such as the most cited papers without the involvement of Ph.D. and/or post-doctoral supervisors should be used to make decisions regarding any given researcher's fellowship award level.

GC-MS Chemical Characterization and In Vitro Evaluation of Antioxidant and Toxic Effects Using Drosophila melanogaster Model of the Essential Oil of Lantana montevidensis (Spreng) Briq.

Background and objectives: Natural products such as essential oils with antioxidant potential can reduce the level of oxidative stress and prevent the oxidation of biomolecules. In the present study, we investigated the antioxidant potential of Lantana montevidensis leaf essential oil (EOLM) in chemical and biological models using Drosophila melanogaster. Materials and methods: in addition, the chemical components of the oil were identified and quantified by gas chromatography coupled to mass spectrometry (GC-MS), and the percentage compositions were obtained from electronic integration measurements using flame ionization detection (FID). Results: our results demonstrated that EOLM is rich in terpenes with Germacrene-D (31.27%) and ß-caryophyllene (28.15%) as the major components. EOLM (0.12-0.48 g/mL) was ineffective in scavenging DPPH radical, and chelating Fe(II), but showed reducing activity at 0.24 g/mL and 0.48 g/mL. In in vivo studies, exposure of D. melanogaster to EOLM (0.12-0.48 g/mL) for 5 h resulted in 10% mortality; no change in oxidative stress parameters such as total thiol, non-protein thiol, and malondialdehyde contents, in comparison to control (p > 0.05). Conclusions: taken together, our results indicate EOLM may not be toxic at the concentrations tested, and thus may not be suitable for the development of new botanical insecticides, such as fumigants or spray-type control agents against Drosophila melanogaster.

Breast cancer in Africa: prevalence, treatment options, herbal medicines, and socioeconomic determinants.

Breast cancer is the leading cause of cancer-related deaths in women worldwide. GLOBOCAN estimated about 1.7 million new cases of breast cancer diagnoses worldwide and about 522,000 deaths in 2012. The burden of breast cancer mortality lies in the developing low-income and middle-income countries, where about 70% of such deaths occur. The incidence of breast cancer is also rising in low-income and middle-income countries in Africa as trend towards urbanization, and adoption of Western lifestyles increases. In general, the triple-negative breast cancer (TNBC) subtype tends to be frequent in women of African ancestry. What are the factors contributing to this prevalence? Are there genetic predispositions to TNBC in African women? This review addresses these questions and provides an update on the incidence, survival, and mortality of breast cancer in Africans, with a focus on sub-Saharan Africans. We have also addressed factors that could account for ethical disparities in incidence and mortality. Further, we have highlighted challenges associated with access to essential drug and to healthcare treatment in some African countries and outlined alternative/herbal treatment methods that are increasingly implemented in Africa and other developing nations.

Rhaphiodon echinus (Nees & Mart.) Schauer: Chemical, toxicological activity and increased antibiotic activity of antifungal drug activity and antibacterial.

The association of herbal products with standard antimicrobial drugs has recently gained more attention as a hope to overcome infectious diseases caused by multidrug-resistant microorganisms. Here, we investigated for the first time the antimicrobial (antifungal and antibacterial) activity of ethanolic and aqueous extracts of R. echinus against multiresistant strains of bacteria (E. coli, P. aeruginosa and S. aureus) and fungi (C. albicans, C. krusei and C. tropicalis), as well as potential to enhance the activity of antibiotics drugs. In addition, both extract were chemically characterized and their toxicity was assessed in Artemia salina. Our results demonstrate that aqueous extract of R. echinus caused a significant increase in the activity of antibiotics gentamicin and imipenem, while the ethanolic extract strongly enhanced the antibiotic activity of gentamicin, amikacin, imipenem and ciprofloxacin against P. aeruginosa. However, neither the ethanolic nor the aqueous extracts significantly affect the antibiotic activity of the drugs when tested against S. aureus. Phytochemical analysis of the extracts indicated ellagic acid, caffeic acid and chlorogenic acid as the major components which can be at least in part responsible for the enhanced activity of antibiotics. None of the extracts showed toxicity in A. salina even at the highest concentration tested (1000 µg/mL). All together, our results suggest that the leaf extract of R. echinus can be an effective source of modulating agents.

Chemical Characterization and Trypanocidal, Leishmanicidal and Cytotoxicity Potential of Lantana camara L. (Verbenaceae) Essential Oil.

Drug resistance in the treatment of neglected parasitic diseases, such as leishmaniasis and trypanosomiasis, has led to the search and development of alternative drugs from plant origins. In this context, the essential oil extracted by hydro-distillation from Lantana camara leaves was tested against Leishmania braziliensis and Trypanosoma cruzi. The results demonstrated that L. camara essential oil inhibited T. cruzi and L. braziliensis with IC50 of 201.94 µg/mL and 72.31 µg/mL, respectively. L. camara essential oil was found to be toxic to NCTC929 fibroblasts at 500 µg/mL (IC50 = 301.42 µg/mL). The composition of L. camara essential oil analyzed by gas chromatography-mass spectrometry (GC/MS) revealed large amounts of (E)-caryophyllene (23.75%), biciclogermacrene (15.80%), germacrene D (11.73%), terpinolene (6.1%), and sabinene (5.92%), which might be, at least in part, responsible for its activity. Taken together, our results suggest that L. camara essential oil may be an important source of therapeutic agents for the development of alternative drugs against parasitic diseases.

Antimicrobial Activity and Modulatory Effect of Essential Oil from the Leaf of Rhaphiodon echinus (Nees & Mart) Schauer on Some Antimicrobial Drugs.

BACKGROUND: Rhaphiodon echinus is a weed plant used in the Brazilian folk medicinal for the treatment of infectious diseases. In this study, the essential oil of R. echinus leaf was investigated for its antimicrobial properties. METHODS: The chemical constituents of the essential oil were characterized by GC-MS. The antimicrobial properties were determined by studying by the microdilution method the effect of the oil alone, and in combination with antifungal or antibiotic drugs against the fungi Candida albicans, Candida krusei and Candida tropicalis and the microbes Escherichia coli, Staphylococcus aureus and Pseudomonas. In addition, the iron (II) chelation potential of the oil was determined. RESULTS: The results showed the presence of ß-caryophyllene and bicyclogermacrene in major compounds, and revealed a low antifungal and antibacterial activity of the essential oil, but a strong modulatory effect on antimicrobial drugs when associated with the oil. The essential oil showed iron (II) chelation activity. CONCLUSIONS: The GC-MS characterization revealed the presence of monoterpenes and sesquiterpenes in the essential oil and metal chelation potential, which may be responsible in part for the modulatory effect of the oil. These findings suggest that essential oil of R. echinus is a natural product capable of enhancing the antibacterial and antifungal activity of antimicrobial drugs.

HPLC-DAD phenolic profile, cytotoxic and anti-kinetoplastidae activity of Melissa officinalis.

Context Melissa officinalis subsp. inodora Bornm. (Lamiaceae) has been used since ancient times in folk medicine against various diseases, but it has not been investigated against protozoa. Objective To evaluate the activities of M. officinalis against Leishmania braziliensis, Leishmania infantum and Trypanosoma cruzi as well as its cytotoxicity in fibroblast cell line. Materials and methods The fresh leaves were chopped into 1 cm(2) pieces, washed and macerated with 99.9% of ethanol for 72 h at room temperature. Antiparasitic activity of M. officinalis was accessed by direct counting of cells after serial dilution, while the cytotoxicity of M. officinalis was evaluated in fibroblast cell line (NCTC929) by measuring the reduction of resazurin. The test duration was 24 h. High-performance liquid chromatography (HPLC) was used to characterise the extract. Results The extract at concentrations of 250 and 125 µg/mL inhibited 80.39 and 54.27% of promastigote (LC50 value = 105.78 µg/mL) form of L. infantum, 80.59 and 68.61% of L. brasiliensis (LC50 value = 110.69 µg/mL) and against epimastigote (LC50 value = 245.23 µg/mL) forms of T. cruzi with an inhibition of 54.45 and 22.26%, respectively, was observed. The maximum toxicity was noted at 500 µg/mL with 95.41% (LC50 value = 141.01 µg/mL). The HPLC analysis identified caffeic acid and rutin as the major compounds. Discussion The inhibition of the parasites is considered clinically relevant (< 500 µg/mL). Rutin and caffeic acids may be responsible for the antiprotozoal effect of the extract. Conclusion The ethanol extract of M. officinalis can be considered a potential alternative source of natural products with antileishmania and antitrypanosoma activities.

Polyphenolic Composition and Evaluation of Antioxidant Activity, Osmotic Fragility and Cytotoxic Effects of Raphiodon echinus (Nees & Mart.) Schauer.

Raphiodon echinus (R. echinus) is used in Brazilian folk medicine for the treatment of inflammation, coughs, and infectious diseases. However, no information is available on the potential antioxidant, cytotoxicity and genotoxicity of this plant. In this study, the polyphenolic constituents, antioxidant capacity and potential toxic effects of aqueous and ethanolic extracts of R. echinus on human erythrocytes and leukocytes were investigated for the first time. R. echinus extracts showed the presence of Gallic, chlorogenic, caffeic and ellagic acids, rutin, quercitrin and quercetin. Aqueous and ethanolic extracts of R. echinus exhibited antioxidant activity in DPPH radical scavenging with IC50 = 111.9 µg/mL (EtOH extract) and IC50 = 227.9 µg/mL (aqueous extract). The extracts inhibited Fe(2+) (10 µM) induced thiobarbituric acid reactive substances (TBARS) formation in rat brain and liver homogenates. The extracts (30-480 µg/mL) did not induce genotoxicity, cytotoxicity or osmotic fragility in human blood cells. The findings of this present study therefore suggest that the therapeutic effect of R. echinus may be, in part, related to its antioxidant potential. Nevertheless, further in vitro and in vivo studies are required to ascertain the safety margin of its use in folk medicine.

Response to carvacrol monoterpene in the emergence of Allium cepa L. seeds exposed to salt stress.

Abiotic stresses including sodium chloride (NaCl) are known to negatively affect plant physiology and seed germination by inducing a delay in establishing seedling emergence. The monoterpene carvacrol is the major component of several aromatic plants and seems to interfere with germination and seedling growth. In this study, we investigated whether treatment with carvacrol attenuates the effects of NaCl on the germination and development of Allium cepa, where biochemical parameters were also analyzed. The results showed that the Emergency Speed Index (ESI) was near to 2.0 in the control group. The groups NaCl, carvacrol alone, and in co-treatment with NaCl exhibited an ESI below 0.8, being significantly smaller when compared to the control. NaCl + carvacrol significantly inhibited seed emergence in relation to the NaCl group. Only the content of malondialdehyde was significantly altered by NaCl.

Bibliometric analysis of endocrinology, diabetes and metabolism research in South Asia from (2012-2021): Comparison with five developed countries.

BACKGROUND AND AIMS: In the present study the research output of the South Asian region (India, Pakistan, Bangladesh, Sri Lanka, Nepal, Maldives, and Bhutan) in endocrinology, diabetes and metabolism (EDM) is highlighted. It was compared with five scientifically advanced countries i.e. USA, UK, Italy, Japan and China. METHODS: On September 13, 2022, the data was retrieved from the Scopus database. The analysis focused on the number of publications, total citations (TC), citations per paper (CPP), field-weighted citations impact (FWCI), and degree of international collaboration. RESULTS: In South Asia, India produced the highest number of publications (n = 7048), followed by Pakistan (n = 799), Bangladesh (n = 345), Sri Lanka (n = 256), Nepal (n = 144), Maldives (n = 12) and Bhutan (n = 4). The highest CPP (n = 19.4) and FWCI (n = 1.18) was recorded for Sri Lanka. Furthermore, USA (n = 64022), China (n = 23991), UK (n = 21449), Italy (n = 18884), and Japan (n = 12875), published the highest number of documents with the highest citations and FWCI in the world. It was noted that India published the highest number of documents (n = 47.28%) in the quartiles (Q) 6 and Q7. Pakistan produced the highest number of documents (n = 64.22%) in the top 50% of journals (Q1 to Q5). South Asian countries produced 8332 publications, with 130382 TC, 15.6 CPP and 1.06 FWCI. Importantly 46.50% of documents from South Asian countries were published in Q6 and Q7 journals. In contrast USA, UK, Italy, Japan and China published 77% documents in top 50% journals. CONCLUSIONS: Although the South Asian research publications have increased yearly (from 2012 to 2021), but approximately 50% of the South Asian output were in the lower quartile journals. Consequently, significant measures are needed to improve the quantity and quality of EDM research produced in South Asian coutries.

Catuaba (Trichilia catigua) prevents against oxidative damage induced by in vitro ischemia-reperfusion in rat hippocampal slices.

Oxidative stress is implicated in brain damage associated with ischemia-reperfusion. Natural antioxidants found in some plants used in folk medicine have been indicated as potential neuroprotective agents. Here we investigated whether Trichilia catigua, a traditional Brazilian herbal medicine alleged to exhibit a variety of neuropharmacological properties (antidepressant, anti-neurasthenic, anti-inflammatory etc.), could have neuroprotective properties in rat hippocampal slices subjected to 2 h oxygen and glucose deprivation (OGD) followed by 1 h reperfusion. Ischemia-reperfusion (I/R) significantly decreased mitochondrial viability, increased dichlorofluorescein oxidation above control both in the incubation medium and slices homogenates, increased lactate dehydrogenase into the incubation medium and decreased non-protein thiols. T. catigua (40-100 µg/mL) protected slices from the deleterious effects of OGD when present before OGD and during the reperfusion periods. Oxidative stress in the medium was also determined under different conditions and the results demonstrated that T. catigua could not protect slices from I/R when it was added to the medium after ischemic insult. Although the translation to a real in vivo situation of I/R is difficult to be done, the results indicated that T. catigua should be used as preventive and not as a curative agent against brain damage.