Effects of coenzyme Q10 and N-acetylcysteine on experimental poisoning by paracetamol in Wistar rats.

Paracetamol (PAR) is a drug widely used in human and veterinary medicine as an analgesic and antipyretic, often involved in cases of intoxication. The most common clinical signs result from damage to red blood cells and hepatocytes, and this intoxication is considered a model for the induction of acute liver failure. In the present study, the hepatoprotective effects of coenzyme Q10 (CoQ10) and N-acetylcysteine (NAC) against experimental paracetamol (PAR) poisoning were analysed. Thirty-five adult Wistar rats (Rattus novergicus albinus) were randomly assigned to five groups, and thirty-one of these survived the treatments. Negative control group (CON-) received 1mL of 0.9% NaCl orally (PO). Other groups received 1.2g/kg of PAR (PO). Positive control group (CON+) received only PAR. NAC group received 800 mg/kg intraperitoneally (IP) of NAC 1h after the administration of PAR and at 12 h received 1mL of 0.9% NaCl, IP. The fourth group (CoQ10) received 1h and 12 h after intoxication, CoQ10 (10mg/kg IP). And the fifth group (NAC+CoQ10) received NAC (800mg/kg, IP) and CoQ10 (10mg/kg, IP). After 12 hours, the rats were euthanized and necropsied to collect liver and kidney tissues for histopathological evaluation and electronic microscopy. A single dose of PAR caused severe acute hepatitis. NAC couldn't reverse the liver and kidney damages. The group that received CoQ10 and NAC had moderate liver damage, while the group that received only CoQ10 had lower values of liver enzymes and mild liver and kidney damage. Animals that received treatment with CoQ10 or NAC+CoQ10 presented normal hepatocyte mitochondria and nuclei. Although CoQ10 couldn't reverse PAR organ damage, results indicate promising hepatoprotection in Wistar rats.

Effect of the addition of different concentrations of Solanum glaucophyllum desf. extract on chondrocyte cultures from the growth cartilage of newborn rats.

Solanum glaucophyllum Desf. is a calcinogenic plant responsible for enzootic calcinosis that affects ruminants and causes alterations in bone and cartilaginous tissues, among others. It is believed that changes in cartilage tissue, with reduced bone growth, are due to hypercalcitoninism, caused by excess vitamin D. However, we hypothesized that S. glaucophyllum Desf. can act directly on chondrocytes and therefore, chondrocyte cultures from the epiphysis of the long bones of newborn rats were used as a model to elucidate the direct effects of S. glaucophyllum Desf. on bone growth. Plant samples were collected from Cañuelas, Argentina. An aliquot of the plant extract was used to quantify vitamin D (1,25(OH)2D3). The effects of the three concentrations of the plant extract were tested in cultures of chondrocytes extracted from the epiphyses of the long bones of 32 three-day-old Wistar rats. A control group (without extract), and three groups treated with different concentrations of plant extract were formed: group 1 (100 µL/L); group 2 (1 mL/L), and group 3 (5 mL/L), containing respectively 1 × 10-9 M, 1 × 10-8 M, and 5 × 10-8 M of 1,25(OH)2D3. After 7, 14, and 21 days of culture, MTT assay for cell viability, alkaline phosphatase activity, and quantification of the percentage of areas with glycosaminoglycans (GAG) stained with periodic acid-Schiff (PAS) were performed. On day 7, all chondrocytes in group 3, that is, those with the highest concentration of plant extract, died. On days 14 and 21, groups 1 and 2 showed a significant reduction in chondrocyte viability compared to the control. At 7, 14, and 21 days, groups 1 and 2 showed significantly lower alkaline phosphatase activity than the control. On day 21, group 2 showed a significant reduction in areas with PAS + GAGs. There were no significant differences between the groups in the expression of gene transcripts for Sox9, Col2, ColX, and aggrecan. The S. glaucophyllum Desf. extract directly affected growing rat chondrocytes by reducing viability, alkaline phosphatase activity, and GAG synthesis without altering the expression of gene transcripts for Sox9, Col2, ColX, and aggrecan, which may be one of the mechanisms by which there is a reduction in bone growth in animals intoxicated by the plant.

The clinical effect of intravenous lipid emulsion on rabbits medicated with diazepam.

Intravenous lipid emulsions (ILE) have been increasingly used to reverse a wide range of lipophilic drug intoxications. However, it is still unknown if these emulsions interfere with other lipophilic drugs routinely used while treating intoxicated patients, such as diazepam, one of the main antiepileptic drugs. Therefore, the objective of the present study was to evaluate whether the administration of a 20% ILE interferes with diazepam's clinical effect. We randomly allocated thirty rabbits to five groups. Three of those groups received diazepam (1.0 mg/kg, IV), one of which did not receive any additional treatment, while the two remaining groups were treated with ILE or lactated ringer solution (1.5 mL/kg followed by 0.25 mL/kg/min for 30 min). The fourth group only received lipid emulsion, and the fifth only lactated ringer. Successive neurological exams at 20 min intervals for a total of 100 min were performed to assess the rabbits' neurological state. We concluded that the ILE did not interfere with diazepam's clinical effect but, although unlikely, the possibility of recurrence of a sedative effect should be considered.

Extreme lymphocytosis in a dog with T-zone lymphoma.

Background: Canine T-zone lymphoma (TZL) is recognized as an indolent CD45-T cell lymphoma, with low aggressiveness and high overall survival. The diagnosis is obtained by histopathology and immunohistochemistry, but also by cytological examination of the lymph node associated with immunophenotyping. Lymphocytosis is commonly identified as around 10,000 cells/µl and may reach 30,760 cells/µl. Case Description: The present report describes a case of a female Golden Retriever, nine years old, with generalized lymphadenopathy. In the cytological examination of the superficial cervical lymph node, a monomorphic population of small, "clear cells" and "hand mirror" lymphocyte shape was suggestive of TZL. The leukogram showed intense leukocytosis (160,050 cells/µl) due to small clear cell lymphocytosis (152,048 cells/µl). The myelogram showed a myeloid:erythroid ratio of 2:3; with a pyramidal distribution of cell types and the presence of 22.8% of lymphocytes in the differential count. Bone marrow, peripheral blood, and lymph node immunophenotyping resulted in lymphocyte gates with 97.3% to 99.5% CD5+, predominantly CD4-, CD8-, and CD45- confirming the diagnosis of TZL with associated leukemia. Treatment with chlorambucil and prednisolone was started. During the first month, the lymphocytosis remained above 200,000 cells/uL. After four months of treatment, there was a decrease in lymphocytes, which progressively reached a count of 10,800 cells/ul in the eleventh month. Conclusion: In the literature, lymphocytosis above 30,760 cells/µl has not been observed in TZLs. Thus, it is believed that this is the first report of extreme lymphocytosis with a slow response to chemotherapy.

Doxorubicin cardiotoxicity and Camellia sinensis cardioprotection determined by speckle-tracking echocardiography

Abstract Doxorubicin (Dox) is a medication used in the treatment of cancerous tumors and hematologic malignancies with potentially serious side effects, including the risk of cardiotoxicity. Flavonoids are plant metabolites with antioxidant properties and can be extracted from Camellia sinensis (CS). The aim of this study is to evaluate the possible cardioprotective effect of CS against injuries induced by Dox in rats. A total of 32 animals were distributed into four groups: (1) control - intraperitoneal injection (I.P.) of 0.5 mL saline weekly and 1.0 mL water by gavage daily; (2) CS - 0.5 mL saline I.P. weekly and 200 mg/kg CS by gavage daily; (3) Dox - 5.0 mg/kg Dox I.P. weekly and 1.0 mL water by gavage daily; and (4) Dox+CS -5.0 mg/kg Dox I.P. weekly and 200 mg/kg CS by gavage daily. Clinical examinations, blood profiles, electrocardiograms, echocardiograms, and histological analyses of hearts were performed over 25 days. The animals in the Dox group showed changes in body weight and in erythrogram, leukogram, electrocardiography, and echocardiography readings. However, animals from the dox+CS group had significantly less change in body weight, improved cardiac function, and showed more preserved cardiac tissue. This study demonstrated that CS prevents dox-induced cardiotoxicity, despite enhancing the cytotoxic effect on blood cells

Natural cururu toad (Rhinella sp.) poisoning in a free-ranging lesser grison (Galictis cuja): Outcomes in a new susceptible predator with a novel peptide description.

Cururu toad (Rhinella marina group) is widely distributed in Brazil. Lesser grison (Galitic cuja) is a South American mustelid. This is the first report of natural poisoning in a free-ranging lesser grison by Rhinella toad parotoid gland secretion (PGS). Five minutes after biting a toad, the lesser grison developed convulsion, dying within 1.5 h. Mass spectrometry analysis of a milky-whitish secretion found in the lesser grison oral cavity allowed identification of a bufotoxin and a new bufonid peptide.

Preclinical toxicological study of long-circulating and fusogenic liposomes co-encapsulating paclitaxel and doxorubicin in synergic ratio.

Combination therapy between paclitaxel (PTX) and doxorubicin (DXR) is applied as the first-line treatment of breast cancer. Co-administration of drugs at synergistic ratio for treatment is facilitated with the use of nanocarriers, such as liposomes. However, despite the high response rate of solid tumors to this combination, a synergism of cardiotoxicity may limit the use. Thus, the objective of this work was to investigate the toxicity of long-circulating and fusogenic liposomes co-encapsulating PTX and DXR at the synergistic molar ratio (1:10) (LCFL-PTX/DXR). For this, clinical chemistry, histopathological analysis and electrocardiographic exams were performed on female Balb/c mice that received a single intravenous dose of LCFL-PTX/DXR. The results of the study indicated that the LD50 dose range (lethal dose for 50% of animals) of the LCFL-PTX/DXR treatment (28.9-34.7 mg/kg) is much higher than that found for free PTX/DXR treatment (20.8-23.1 mg/kg). In addition, liposomes promoted cardiac protection by not raising CK-MB levels in animals, keeping cardiomyocytes without injury or electrocardiographic changes. After 14 days of treatment, free PTX/DXR caused prolongation of the QRS interval when compared to LCFL-PTX/DXR treatment at the same dose (37.0 ± 5.01 ms and 30.83 ± 2.62 ms, respectively, with p = 0.017). The survival rate of animals treated with LCFL-PTX/DXR was three times higher than that of those treated with free drugs. Thus, it was established that the toxicity of LCFL-PTX/DXR is reduced compared to the combination of free PTX/DXR and this platform has advantages for the clinical treatment of breast cancer.

Intravenous lipid emulsion treatment in rabbits with ivermectin toxicosis.

OBJECTIVE: To determine the effect and safety of IV lipid emulsion in rabbits with acute ivermectin toxicosis. DESIGN: Randomized controlled trial. SETTING: University research facility. ANIMALS: Twenty-four healthy male adult New Zealand rabbits. INTERVENTIONS: Three groups of rabbits (IV, IV_RL, and IV_LE) received 80 mg/kg of ivermectin (8 mL/kg) through a nasogastric tube, and 1 group (LE) received an equivalent volume (8 mL/kg) of 0.9% sodium chloride. Group IV_RL was treated with Ringer's lactate (2 mL/kg bolus, followed by 0.25 mL/kg/min for 60 minutes), whereas groups IV_LE and LE received 20% lipid emulsion. The rabbits were submitted to clinical and neurological evaluation, and blood samples were collected for biochemical analysis. All animals were euthanized, and tissue samples were collected and processed for histopathological evaluation and ivermectin quantification. MEASUREMENTS AND MAIN RESULTS: All animals exposed to ivermectin manifested clinical changes consistent with toxicosis, but the ones that received IV lipid emulsion infusion showed no significant clinical improvement. Intense increase in serum glucose and triglyceride concentrations was seen after ivermectin exposure, along with increased urea and creatinine concentrations, but the last 2 remained within the reference range. Lipid emulsion caused an intense increase in triglycerides and cholesterol concentrations. No pathological abnormalities were seen in the organs sampled. Toxicological analysis showed greater ivermectin concentration in adipose tissue and liver, followed by kidney and, finally, brain. The treatments did not change ivermectin tissue concentration. CONCLUSIONS: When given to rabbits intoxicated with ivermectin, IV lipid emulsion was biochemically and histologically safe but was not effective in treating, delaying, or reversing clinical signs and progression, nor did it alter ivermectin tissue concentration.

Cardiotoxic Effects of Micrurus surinamensis (Cuvier, 1817) Snake Venom.

Micrurus surinamensis is a coral snake from the Elapidae family of wide distribution in Amazonia Forest. Its venom contains neurotoxins that induce muscular and respiratory paralysis; however, its cardiovascular action is not yet characterized. The aim of this study was to investigate the cardiotoxic effects caused by M. surinamensis poisoning in rodents. Twelve guinea pigs (Cavia porcellus) were distributed in two groups (n = 6) named as control and envenomed. The control group received 0.2 ml of PBS/BSA via intramuscular injection (IM), while envenomed animals received 0.75 µg of venom per g of body weight, also via IM. Electrocardiographic examination (ECG) and biochemical serum tests were conducted before and 2 h after inoculation. ECG of the envenomed animals revealed severe progressive arrhythmias including atrioventricular block, supraventricular, and ventricular extrasystoles. Serum biochemistry showed significant increase in CK, CK-MB, and LDH enzymes corroborating the skeletal and cardiac muscle damage. Myonecrosis and degeneration were observed in both skeletal and heart muscle; nevertheless, transmission electron microscopy revealed cardiac muscle fibers fragmentation. In conclusion, M. surinamensis venom has a potent cardiotoxic activity eliciting arrhythmogenic effects and heart damage after only 2 h of envenomation.

Fatal metaldehyde poisoning in a dog confirmed by gas chromatography.

BACKGROUND: Metaldehyde is a toxic pesticide used mainly as a molluscicide, responsible for intoxication and deaths in both humans and animals. Accidental exposure to metaldehyde in dogs is considered rare, but severe. Data concerning clinical and veterinary forensic toxicology are largely incomplete, especially regarding case reports in dogs. The present work reports a complete and detailed description of a case from the history, clinical evolution, pathological exams and toxicological diagnosis in an accidental case of metaldehyde poisoning in dog. CASE PRESENTATION: An eleven-month-old, 3.0 kg, male German Spitz was presented for emergency care with acute vomiting and seizures 3 hours after suspected accidental ingestion of commercial molluscicide containing 3% metaldehyde (Lesmax®). The animal was in lateral recumbency and showed stuporous mentation, salivation, tonic-clonic status epilepticus, systemic tremors, bilateral miosis, absent palpebral, corneal, oculovestibular and gag reflexes, severely depressed spinal reflexes, dyspnea and tachycardia. Despite treatment, the patient progressed to comatose mentation and died. Necropsy examination revealed discrete lesions in the liver and central nervous system, while stomach examination revealed content of feed, activated charcoal and blue-green granules, compatible to the commercial formula of metaldehyde. Histology examination revealed extensive hemorrhage and severe centrolobular necrosis of the liver and tumefaction of Kupfer cells. Brain samples showed discrete hemorrhage and hyperemia. In order to confirm the diagnosis, samples from feces, stomach content, spleen, liver, heart, kidneys and brain were submitted gas chromatography analysis. Results confirmed the presence of metaldehyde in all samples. We describe clinicopathological abnormalities of a fatal case of metaldehyde poisoning in a dog, as well as postmortem diagnosis using gas chromatography. CONCLUSION: Metaldehyde poisoning is rarely reported, since the diagnosis is often difficult and the notifications scarce. To our knowledge, this is the first report describing clinical signs, pathological findings and chromatographic diagnosis. This report aims to contribute to the understanding of the pathogenesis of metaldehyde intoxication, to further explore veterinary forensic toxicology diagnosis.

The Solanum glaucophyllum Desf. extract reduces mineralized matrix synthesis in osteogenically differentiated rat mesenchymal stem cells in vitro.

The Solanum glaucophyllum Desf. has been used to treat and prevent diseases in human and veterinary medicine. On the other hand, plant poisoning causes several bone diseases, among them osteoporosis, which is characterized by osteoblastic hypoplasia. Because the osteoblast is a cell derived from the differentiation of mesenchymal stem cells (MSCs) from bone marrow, the hypothesis is that the plant reduces the osteogenic differentiation of MSCs. The objective of this study was to evaluate the effects of S. glaucophyllum Desf. extract on MSCs cultured in osteogenic differentiation medium. We determined by liquid chromatography that 1 ml of plant extract contained 3.8 µl of 1,25(OH)2 D3 (calcitriol). Four groups of MSCs cultivated in osteogenic medium were evaluated as follows: (a) treated with 100 µl of extract/L containing 0.4 µg/L of calcitriol; (b) treated with 1 ml of extract/L containing 4 µg/L of calcitriol; (c) treated with 5 ml of extract/L containing 20 µg/L of calcitriol; and (d) a control group without extract. We performed alkaline phosphatase activity assay, analysis of MTT conversion to formazan, and evaluated the percentage of cells, and number and diameter of mineralization nodules. The expression of gene transcripts for osteopontin, bone sialoprotein and BMP-2 was analysed by RT-qPCR. After 21 days, there was a significant reduction in MTT conversion to formazan in treated groups, of the cellularity in the group with 5 ml of extract/L, and in the number and size of mineralization nodules in the groups treated with 1 and 5 ml of extract/L. The 5 ml extract/L concentration also reduced transcript expression of osteopontin. It is concluded that S. glaucophyllum Desf. at concentrations of 1 and 5 ml extract/L reduced mineralized matrix synthesis in MSCs cultivated in osteogenic differentiation medium, which suggests that this is one of the mechanisms by which osteoporosis occurs in intoxicated animals.

Rat mesenchymal stem cell cultures as a model to elucidate the cellular and molecular pathogenesis of bone metaplasia induced by Solanum glaucophyllum intoxication.

The hypothesis of this experiment is that mesenchymal stem cells (MSCs) are involved in the genesis of the bone metaplasia caused by Solanum glaucophyllum intoxication. We determined using liquid chromatography that 1 mL of plant extract contained 3.8 µl of 1,25(OH)2D3. The ability of 100 µL, 1 mL and 5 mL of extract/L, containing 1 nM (0.4 µg/L), 10 nM (4 µg/L) and 50 nM (20 µg/L) of 1,25(OH)2D3, respectively, in inducing the osteogenic differentiation in bone marrow MSCs from rats was tested. At the concentrations of 1 and 5 mL of extract/L of culture medium without osteogenesis-inducing factors, the plant extract induced the osteogenic differentiation of the MSCs, as was evidenced by the greater synthesis of mineralized matrix. At the higher concentration (5 mL of extract/L), an increase in the relative expression of BMP-2 gene was observed. It was concluded that rat bone marrow MSC culture is a good model for studying the effects of the S. glaucophyllum extract on the osteogenic differentiation of undifferentiated cells. Also, S. glaucophyllum extracts containing 10 nM (4 µg/L) and 50 nM (20 µg/L) of 1,25(OH)2D3 induce the osteogenic differentiation of MSCs, suggesting that this is one of the mechanisms by which S. glaucophyllum causes bone metaplasia.

A review of cardiac glycosides: Structure, toxicokinetics, clinical signs, diagnosis and antineoplastic potential.

Cardiac glycosides (CGs) are secondary compounds found in plants and amphibians and are widely distributed in nature with potential cardiovascular action. Their mechanism is based on the blockage of the heart's sodium potassium ATPase, with a positive inotropic effect. Some of the most well-known CGs are digoxin, ouabain, oleandrin, and bufalin. They have similar chemical structures: a lactone ring, steroid ring, and sugar moiety. Digoxin, ouabain, and oleandrin are classified as cardenolides, consisting of a lactone ring with five carbons, while bufalin is classified as bufodienolides, with a six-carbon ring. Small structural differences determine variations in the toxicokinetics and toxicodynamics of such substances. Most case reports of poisoning caused by CGs are associated with cardiovascular toxicity, causing a variety of arrhythmias and lesions in the heart tissue. Experimental studies also describe important similarities among different CGs, especially regarding species sensitivity. Recent studies furthermore focus on their antineoplastic potential, with controversial results. Data from research studies and case reports were reviewed to identify the main characteristics of the CGs, including toxicokinetics, toxicodynamics, clinical signs, electrocardiographic, pathological findings, antineoplastic potential and the main techniques used for diagnostic purposes.

Multiresidue method for detection of pesticides in beef meat using liquid chromatography coupled to mass spectrometry detection (LC-MS) after QuEChERS extraction.

Beef meat is an important food that can be contaminated by pesticides. This study aimed to optimize a multiresidue method for identification and quantification of pesticides in beef meat by liquid chromatography coupled to mass spectrometry detection (LC-MS). The extraction and clean-up procedures were adapted from the QuECHERS method. From the 188 analytes tested, the method was validated as qualitative method for 19 compounds and as quantitative method for 152 compounds. The results were satisfactory, yielding coefficients of variation of less than 20% and recoveries ranging from 70% to 120% and expanded uncertainty of less than 50%. The quantification limit was typically 10 µg kg-1 (but 25 µg kg-1 for 12 of the compounds) and the detection limit was 5.0 µg kg-1. Thirty-two real samples of commercialized beef meat were analyzed without any residual pesticide being found. Thus, the results showed that the multiresidue method for detecting 171 pesticides, using adapted QuECHERS for extraction and LC-MS for detection, is suitable for analyzing beef meat.

Different leaf extracts from Brunfelsia uniflora in mice / Diferentes extratos das folhas de Brunfelsia uniflora em camundongos

ABSTRACT: In Brazil, at least 16 poisonous plant species can affect the central nervous system of livestock. Recently in the state of Piauí, Northeastern Brazil, Brunfelsia uniflora was reported as a cause of nervous signs in donkeys, cattle, and small ruminants. In order to assess the toxicity of B. uniflora extracts, 20 Swiss mice were distributed into four groups (n=5) receiving by gavage alkaloids, flavonoids, saponins, or saline (control group). After administration of the extracts in a single dose (5g kg-1), all mice were observed daily for clinical signs. Mice that received the extracts showed moderate to severe clinical signs, including piloerection, vocalization, and seizures. All mice dosed with saponins died between 10 and 20min after administration. Serum biochemical evaluation of animals that received saponins revealed slight increases in total protein levels and decreased magnesium and chlorite levels. In conclusion, saponins of B. uniflora leaves induced acute toxic neurological effects and death in mice.

RESUMO: No Brasil, pelo menos 16 espécies de plantas tóxicas podem afetar o sistema nervoso central dos bovinos. Recentemente no estado do Piauí, no Nordeste do Brasil, Brunfelsia uniflora foi relatada como causadora de sinais nervosos em jumentos, bovinos e pequenos ruminantes. Para avaliar a toxicidade de B. uniflora, 20 camundongos foram distribuídos em quatro grupos de cinco animais recebendo diferentes extratos da planta. Os extratos de alcalóides, flavonóides, saponinas ou solução salina (grupo controle) foram administrados por gavagem. Após a administração dos extratos, em dose única (5g kg-1), todos os animais foram observados diariamente. Os camundongos que receberam os extratos de B. uniflora apresentaram sinais clínicos moderados a graves, incluindo piloeração, vocalização e convulsões. Todos os camundongos que receberam extrato de saponinas morreram entre 10 e 20 minutos após. A avaliação bioquímica sérica dos animais que receberam saponinas, revelou discretos aumentos nos níveis de proteína total e diminuição nos níveis de magnésio e cloro. Conclui-se que, as saponinas presentes nas folhas de B. uniflora induzem efeitos neurológicos tóxicos agudos e, morte em camundongos.

Could mesenchymal stem cell therapy help in the treatment of muscle damage caused by Bothrops alternatus venom? / Podem as células tronco mesenquimais auxiliarem no tratamento da lesão muscular causada pelo veneno de Bothrops alternatus?

ABSTRACT: The aim of this study was to evaluate the use of mesenchymal stem cells (MSC) in the treatment of myonecrosis induced by Bothrops alternatus venom in rats. Seventy-five male adult Wistar rats were divided into three experimental groups. G1 and G2 were injected in the gastrocnemius muscle with 120μg of B. alternatus venom, while G3 received 200μL of PBS only. Three days after the venom injection, 12 rats from G1 were treated with 5.0 x 106 MSC in PBS, whereas G2 and G3 rats received PBS. Every three days, blood and muscle samples of five animals from each group were taken for serum biochemical and pathological analyses. Histological examinations showed more intense muscle lesions following MSC treatment, characterized by disorganization and loss of muscle fibers, with focal necrosis and inflammatory infiltration by mononuclear cells. In conclusion, the use of MSC for the treatment of local damage caused by inoculation of B. alternatus venom impaired muscle regeneration and interfered in the healing process.

RESUMO: O objetivo do presente trabalho foi avaliar a utilização das células tronco mesenquimais (MSC) no tratamento da mionecrose induzida pelo veneno de Bothrops alternatus em ratos. 75 ratos Wistar adultos foram distribuídos em três grupos experimentais. G1 e G2 receberam 120μg de veneno de B. alternatus, enquanto o G3 recebeu apenas 200μL de PBS. Três dias após a administração do veneno, os ratos do grupo G1 foram tratados com 5.0 x 106 MSC, enquanto G2 e G3 receberam exclusivamente PBS. A cada três dias, amostras de sangue e tecido muscular foram coletadas de cinco animais de cada grupo para avaliação bioquímica sérica e patológica, respectivamente. A análise histológica revelou lesão muscular mais intensa após a aplicação das MSC, caracterizada pela desorganização e perdas das fibras musculares, com necrose focal e infiltrado inflamatório mononuclear. É possível concluir que a utilização das MSC para o tratamento da lesão local causada pela inoculação do veneno B. alternatus deteriorou a regeneração muscular e interferiu com o processo de cicatrização.

Avaliação físico-química de amostras de água, sedimento e mata ciliar de uma piscicultura localizada em área agroindustrial à margem do Ribeirão da Mata (MG) / Physicochemical analysis of water, sediment and riparian vegetation of a fish farming located in an agroindustrial area at the border of Ribeirão da Mata (Minas Gerais, Brazil)

RESUMO Objetivou-se realizar uma avaliação físico-química de amostras de água, sedimento e mata ciliar em uma piscicultura localizada próxima às margens do Ribeirão da Mata, Minas Gerais. As coletas de água foram semanais em quatro pontos assim denominados: (1) nascente; (2) entrada do sistema; (3) efluente concentrado e (4) ponto de lançamento. Foram monitorados os seguintes parâmetros físico-químicos: temperatura (ºC), pH, oxigênio dissolvido, demanda bioquímica de oxigênio, fósforo total, alcalinidade, sólidos dissolvidos totais, fosfato, nitrato, nitrito, sulfato, amônia e fenol das amostras de água. Foram pesquisados metais pesados (chumbo, cádmio, mercúrio e zinco) e agrotóxicos (organoclorados, organofosforados, clorofosforados, carbamatos, piretroides e rodenticidas anticoagulantes) nas amostras de água, sedimento e mata ciliar. Alcalinidade e sólidos totais apresentaram as maiores concentrações, provavelmente devido às características geológicas,por se tratar de região cárstica. Fenol, em todos os pontos, e fosfato, nos pontos 3 e 4, apresentaram valores acima dos limites permitidos para a classe II de água doce, segundo a Resolução CONAMA nº 357. Os outros parâmetros (amônia, nitrato, nitrito e sulfato), em todos os pontos de coleta, apresentaram baixos valores. Nas amostras de água não foram detectados chumbo e mercúrio; zinco apresentou valores abaixo de 0,007 mg.L-1. As amostras de sedimento apresentaram valores de chumbo entre 11,1566 e 37,0438 mg.L-1, estando 12 dessas acima do valor de referência de qualidade. Também em todas as amostras de sedimento foi detectado mercúrio, que variou de 0,35 a 0,82 mg.L-1. Em relação ao cádmio, esse não foi detectado nas amostras de sedimento e plantas. Também não foram detectados agrotóxicos em nenhuma das amostras estudadas.

ABSTRACT The aim of this study was to carry out a physicochemical analysis of water, sediment and riparian vegetation in a fish farm located near the Ribeirão da Mata basin in Minas Gerais State (Brazil). The water samples were collected weekly at four points: (1) source, (2) system entry, (3) discharge point, (4) and point release. The monitored physicochemical parameters in the water samples were: temperature (ºC), pH, dissolved oxygen, biochemical oxygen demand, total phosphorus, alkalinity, total dissolved solids, phosphate, nitrate, nitrite, sulfate, ammonia and phenol. Heavy metals (lead, cadmium, mercury and zinc) and pesticides (organochlorine, organophosphates, clorofosforados, carbamates, pyrethroids and anticoagulant rodenticides) were searched in the samples of water, sediment and riparian vegetation. Alkalinity and total solids presented the highest concentration, probably due to geological features of a carstic area. Phenol, at all points, and phosphate, at points 3 and 4, showed values above the limits allowed for class II freshwater, according to the CONAMA Resolution n. 357. The other parameters (ammonia, nitrate, nitrite and sulfate) in all sampling sites showed low values. It was not detected lead and mercury in the water samples; and zinc values were below 0.007 mg.L-1. However, the sediment samples showed lead values from 11.1566 to 37.0438 mg.L-1, with 12 of those samples above the quality reference value. In addition, it was detected mercury in all sediment samples, which ranged from 0.35 to 0.82 mg.L-1. It was not detected cadmium in samples of sediment neither plants. No pesticides were detected in the samples.

Cardiorespiratory alterations in rodents experimentally envenomed with Hadruroides lunatus scorpion venom

Abstract Background Hadruroides lunatus is the most abundant scorpion species in the Peruvian central coast, where most of the accidents involving humans are registered. In spite of its prevalence, there are only very few studies on H. lunatus envenomation. The aim of the present study was to analyze the cardiorespiratory alterations caused by H. lunatus envenomation in rodents. Methods Wistar rats injected with H. lunatus scorpion venom were submitted to electrocardiography. After euthanasia, rat lungs were collected and histopathologically analyzed. Mouse cardiomyocytes were used to perform immunofluorescence and calcium transient assays. Data were analyzed by ANOVA or Student’s t-test. The significance level was set at p< 0.05. Results It was observed that H. lunatus venom increased heart rate and caused arrhythmia, thereby impairing the heart functioning. Lungs of envenomed animals showed significant alterations, such as diffuse hemorrhage. In addition, immunofluorescence showed that H. lunatus venom was capable of binding to cardiomyocytes. Furthermore, mouse ventricular cardiomyocytes incubated with H. lunatus venom showed a significant decrease in calcium transient, confirming that H. lunatus venom exerts a toxic effect on heart. Conclusion Our results showed that H. lunatus venom is capable of inducing cardiorespiratory alterations, a typical systemic effect of scorpionism, stressing the importance of medical monitoring in envenomation cases.

Cardiorespiratory alterations in rodents experimentally envenomed with Hadruroides lunatus scorpion venom

Abstract Background Hadruroides lunatus is the most abundant scorpion species in the Peruvian central coast, where most of the accidents involving humans are registered. In spite of its prevalence, there are only very few studies on H. lunatus envenomation. The aim of the present study was to analyze the cardiorespiratory alterations caused by H. lunatus envenomation in rodents. Methods Wistar rats injected with H. lunatus scorpion venom were submitted to electrocardiography. After euthanasia, rat lungs were collected and histopathologically analyzed. Mouse cardiomyocytes were used to perform immunofluorescence and calcium transient assays. Data were analyzed by ANOVA or Students t-test. The significance level was set at p 0.05. Results It was observed that H. lunatus venom increased heart rate and caused arrhythmia, thereby impairing the heart functioning. Lungs of envenomed animals showed significant alterations, such as diffuse hemorrhage. In addition, immunofluorescence showed that H. lunatus venom was capable of binding to cardiomyocytes. Furthermore, mouse ventricular cardiomyocytes incubated with H. lunatus venom showed a significant decrease in calcium transient, confirming that H. lunatus venom exerts a toxic effect on heart. Conclusion Our results showed that H. lunatus venom is capable of inducing cardiorespiratory alterations, a typical systemic effect of scorpionism, stressing the importance of medical monitoring in envenomation cases.

ω-conotoxin MVIIA intralesional injection in spinal cord injury in rats / Aplicação intralesional da ω-conotoxina MVIIA no trauma medular em ratos

This study aimed to investigate the neuroprotective effect of ω-conotoxin MVIIA (MVIIA) intralesional application in rats submitted to spinal cord injury. Male Wistar rats, weighing 300g±23.4, were distributed in five groups: negative control (SHAM), placebo (PLA), 5μM MVIIA, 10μM MVIIA and 20μM MVIIA MVIIA. After laminectomy of the 12th thoracic vertebra (SHAM), the PLA, 5μM MVIIA, 10μM MVIIA and 20μM MVIIA groups were subjected to acute compressive spinal cord trauma for five minutes, and then five minutes later, the animals received specific treatment in a standard total volume of 2µL, by intralesional route, using sterile PBS as placebo. Locomotor activity was assayed using Basso Beattie Bresnahan (BBB) scale to show the patterning of SCI. With 48 hours of injury, the animals were euthanized, the liquor sample was collected in atlantooccipital space, and also the spinal segment, including the epicenter and caudal region to injury. Assays were performed for mitochondrial viability, serum glutamate, production of reactive oxygen species (ROS) and lipid peroxidation (LP) were performed. The study design was randomized and the data submitted to ANOVA and comparison of means by SNK test, and data from BBB scale were evaluated using Kruskal-Wallis test (P<0.05). There was no significant difference between groups in BBB scores. The MVIIA did not promote decrease in the levels of glutamate, ROS, LP, and did not preserve the mitochondria in the intralesional application five minutes after spinal cord injury in rats.

Objetivou-se investigar o efeito neuroprotetor da aplicação intralesional da MVIIA em ratos submetidos ao trauma medular. Foram utilizados ratos Wistar, machos, com peso entre 300g±23.4, distribuídos em cinco grupos: controle negativo (SHAM), placebo (PLA), 5µM MVIIA, 10µM MVIIA e 20µM MVIIA. Após a laminectomia da vértebra torácica 12 (SHAM), os grupos PLA, 5µM MVIIA, 10µM MVIIA e 20µM MVIIA foram submetidos ao trauma medular agudo compressivo por cinco minutos e, cinco minutos após o trauma, receberam o tratamento específico em volume total padrão de 2µL, pela via intralesional, sendo utilizado como placebo o PBS estéril. A atividade locomotora foi avaliada pela escala proposta por Basso Beattie Bresnahan (BBB), com intuito de mostrar a padronização do trauma medular. Com 48 horas do trauma, os animais foram submetidos à eutanásia, coletou-se amostra do líquor no espaço atlantooccipital e um segmento medular, incluindo o epicentro e região caudal à lesão. Foram realizados ensaios de viabilidade mitocondrial, dosagem de glutamato, produção de espécies reativas de oxigênio (ERO) e peroxidação lipídica (PL). O delineamento do estudo foi inteiramente casualizado e os dados submetidos ao ANOVA, com comparação de médias pelo teste de SNK e os dados do teste BBB foram comparados utilizando o teste Kruskal-Wallis (P<0.05). Em relação aos escores do BBB, não houve diferença entre os grupos. A MVIIA não promoveu a diminuição dos níveis do glutamato, ERO, PL e não preservou a mitocôndria na aplicação intralesional, cinco minutos após o trauma medular em ratos.