ABSTRACT
Abstract This study was carried out to evaluate the effect of Glutamine, as a dipeptide or a free amino acid form, on the progression of burn injuries in rats. Thirty male Wistar rats were burned with a comb metal plate heated in boiling water (98 °C) for three minutes, creating four rectangular full-thickness burn areas separated by three unburned interspaces (zone of stasis) in both dorsum sides. The animals were randomized into three groups (n=10): saline solution (G1-Control) and treated groups that orally received Glutamine as dipeptide (G2-Dip) or free amino acid (G3-FreeAA). Two and seven days after burn injury, lesions were photographed for unburned interspaces necrosis evolution assessment. Seven days after injury, glutathione seric was measured and histopathological analysis was performed. By photographs, there was a significant reduction in necrosis progression in G3-Free-AA between days two and seven. Histopathological analysis at day 7 showed a significantly higher stasis zone without necrosis and a higher number of fibroblasts in G2-Dip and G3-FreeAA compared with G1-Control. Also, glutathione serum dosage was higher in G2-Dip. The plasmatic glutathione levels were higher in the G2-Dip than the G1-Control, and there was a trend to higher levels in G3-FreeAA. The reduction in histological lesions, greater production of fibroblasts, and greater amounts of glutathione may have benefited the evolution of burn necrosis, which showed greater preservation of interspaces.
Resumo Este estudo foi realizado para avaliar o efeito da Glutamina, como um dipeptídeo ou forma de aminoácido livre, na progressão de queimaduras em ratos. Trinta ratos Wistar machos foram queimados com um pente de metal aquecido em água fervente (98 °C) por três minutos, criando quatro áreas retangulares queimadas separadas por três interesespaços não queimados (zona de estase) em ambos os lados do dorso. Os animais foram randomizados em três grupos (n = 10): solução salina (G1-Controle) e grupos tratados que receberam glutamina via oral como dipeptídeo (G2-Dip) ou aminoácido livre (G3-FreeAA). Dois e sete dias após a queimadura, as lesões foram fotografadas para avaliação da evolução da necrose entre os espaços não queimados. Sete dias após a lesão, foi dosada a glutationa sérica e realizada análise histopatológica. Pelas fotografias, houve uma redução significativa na progressão da necrose no G3-Free-AA entre os dias dois e sete. A análise histopatológica no dia 7 mostrou uma zona de estase significativamente maior sem necrose e número mais elevado de fibroblastos em G2-Dip e G3-FreeAA em comparação com G1-Controle. Os níveis plasmáticos de glutationa foram maiores no G2-Dip em relação ao G1-Controle, e houve tendência a níveis mais elevados no G3-FreeAA. A redução das lesões histológicas, maior produção de fibroblastos, maior quantidade de glutationa podem ter beneficiado a evolução da necrose da queimadura, que mostrou maior preservação dos interespaços.
ABSTRACT
Abstract This study was carried out to evaluate the effect of Glutamine, as a dipeptide or a free amino acid form, on the progression of burn injuries in rats. Thirty male Wistar rats were burned with a comb metal plate heated in boiling water (98 °C) for three minutes, creating four rectangular full-thickness burn areas separated by three unburned interspaces (zone of stasis) in both dorsum sides. The animals were randomized into three groups (n=10): saline solution (G1-Control) and treated groups that orally received Glutamine as dipeptide (G2-Dip) or free amino acid (G3-FreeAA). Two and seven days after burn injury, lesions were photographed for unburned interspaces necrosis evolution assessment. Seven days after injury, glutathione seric was measured and histopathological analysis was performed. By photographs, there was a significant reduction in necrosis progression in G3-Free-AA between days two and seven. Histopathological analysis at day 7 showed a significantly higher stasis zone without necrosis and a higher number of fibroblasts in G2-Dip and G3-FreeAA compared with G1-Control. Also, glutathione serum dosage was higher in G2-Dip. The plasmatic glutathione levels were higher in the G2-Dip than the G1-Control, and there was a trend to higher levels in G3-FreeAA. The reduction in histological lesions, greater production of fibroblasts, and greater amounts of glutathione may have benefited the evolution of burn necrosis, which showed greater preservation of interspaces.
Resumo Este estudo foi realizado para avaliar o efeito da Glutamina, como um dipeptídeo ou forma de aminoácido livre, na progressão de queimaduras em ratos. Trinta ratos Wistar machos foram queimados com um pente de metal aquecido em água fervente (98 °C) por três minutos, criando quatro áreas retangulares queimadas separadas por três interesespaços não queimados (zona de estase) em ambos os lados do dorso. Os animais foram randomizados em três grupos (n = 10): solução salina (G1-Controle) e grupos tratados que receberam glutamina via oral como dipeptídeo (G2-Dip) ou aminoácido livre (G3-FreeAA). Dois e sete dias após a queimadura, as lesões foram fotografadas para avaliação da evolução da necrose entre os espaços não queimados. Sete dias após a lesão, foi dosada a glutationa sérica e realizada análise histopatológica. Pelas fotografias, houve uma redução significativa na progressão da necrose no G3-Free-AA entre os dias dois e sete. A análise histopatológica no dia 7 mostrou uma zona de estase significativamente maior sem necrose e número mais elevado de fibroblastos em G2-Dip e G3-FreeAA em comparação com G1-Controle. Os níveis plasmáticos de glutationa foram maiores no G2-Dip em relação ao G1-Controle, e houve tendência a níveis mais elevados no G3-FreeAA. A redução das lesões histológicas, maior produção de fibroblastos, maior quantidade de glutationa podem ter beneficiado a evolução da necrose da queimadura, que mostrou maior preservação dos interespaços.
Subject(s)
Animals , Male , Rats , Burns/drug therapy , Glutamine , Rats, Wistar , Dipeptides , Disease Models, Animal , Amino AcidsABSTRACT
Abstract Objective: to evaluate the effect of photobiomodulation with low-level 660 nm laser alone or associated with Human Amniotic Membrane in the repair of partial-thickness burns in rats. Method: an experimental study conducted with 48 male Wistar rats, randomized into four groups: Control, Human Amniotic Membrane, Low-Level Laser Therapy, and Low-Level Laser Therapy associated with Human Amniotic Membrane. The histopathological characteristics of the skin samples were analyzed 7 and 14 days after the burn. The data obtained were submitted to the Kolmogorov-Smirnov and Mann-Whitney tests. Results: the histological analysis of the burn injuries showed a decrease in inflammation (p<0.0001) and an increase in proliferation of fibroblasts (p<0.0001) mainly at 7 days in all treatments related to the control group. At 14 days, the greater effectiveness in accelerating the healing process was significant (p<0.0001) in the Low-Level Laser Therapy group associated with the Human Amniotic Membrane. Conclusion: the association of photobiomodulation therapies with the Human Amniotic Membrane allowed verifying a reduction in the healing process time of the experimental lesions, stimulating its proposal as a treatment protocol in partial-thickness burns.
Resumo Objetivo: avaliar o efeito da fotobiomodulação com laser de baixa intensidade 660 nm isoladamente ou associada à membrana amniótica humana no reparo de queimaduras de espessura parcial em ratos. Método: estudo experimental com 48 ratos Wistar machos, randomizados em quatro grupos: Controle, Membrana Amniótica Humana, Terapia a Laser de Baixa Intensidade e Terapia a Laser de Baixa Intensidade associado à Membrana Amniótica Humana. As características histopatológicas das amostras de pele foram analisadas aos 7 e 14 dias após a queimadura. Os dados obtidos foram submetidos aos testes de Kolmogorov-Smirnov e Mann Whitney. Resultados: a análise histológica das lesões por queimadura mostrou a diminuição da inflamação (p <0,0001) e aumento da proliferação de fibroblastos (p <0,0001), principalmente nos 7 dias em todos os tratamentos relacionados ao grupo controle. Aos 14 dias, a maior efetividade na aceleração do processo cicatricial foi significativa (p<0,0001) no grupo Terapia a Laser de Baixa Intensidade associado à Membrana Amniótica Humana. Conclusão: a associação das terapias de fotobiomodulação à membrana amniótica humana permitiu comprovar redução no tempo do processo cicatricial das lesões experimentais, estimulando sua proposição como protocolo de tratamento em queimaduras de espessura parcial.
Resumen Objetivo: evaluar el efecto de la fotobiomodulación con láser de baja intensidad 660 nm de sola o combinada con la membrana amniótica humana en la reparación de quemaduras de espesor parcial en ratas. Método: estudio experimental con 48 ratas Wistar macho, aleatorizadas en cuatro grupos: Control, Membrana Amniótica Humana, Terapia con Láser de Baja Intensidad y Terapia con Láser de Baja Intensidad combinada con la Membrana Amniótica Humana. Las características histopatológicas de las muestras de piel fueron analizadas a los 7 y 14 días después de la quemadura. Los datos obtenidos fueron sometidos a las pruebas de Kolmogorov-Smirnov y Mann-Whitney. Resultados: el análisis histológico de las lesiones por quemadura mostró una disminución de la inflamación (p <0,0001) y un aumento de la proliferación de fibroblastos (p <0,0001) principalmente a los 7 días en todos los tratamientos en comparación con el grupo control; a los 14 días, en el grupo de Terapia con Láser de Baja Intensidad combinada con la Membrana Amniótica Humana la mayor efectividad en la aceleración del proceso de cicatrización fue significativa (p<0,0001). Conclusión: la asociación de terapias de fotobiomodulación con la membrana amniótica humana permitió comprobar que hubo una reducción en el tiempo del proceso de cicatrización de lesiones experimentales, lo cual favorece que se proponga como protocolo de tratamiento en quemaduras de espesor parcial.
Subject(s)
Animals , Rats , Skin/injuries , Wound Healing , Burns/pathology , Burns/therapy , Rats, Wistar , Low-Level Light Therapy , Amnion/pathologyABSTRACT
Introduction: Bevacizumab is among the most frequently used drugs in cancer treatment. There is evidence that some anti-angiogenic drugs reduce flap survival, but it is unclear whether this applies to Bevacizumab. We investigated the effect of Bevacizumab on the viability of free flaps in rats. Methods: The animals were randomly assigned to one of three groups. The Graft group received intravascular saline and was submitted to a full-thickness skin graft. The Flap-Saline and the Flap- BVZ groups underwent a free groin flap after receiving, respectively, intravascular saline solution or intravascular administration of Bevacizumab. Results: The Graft group showed a lower percentage of the viable area (22.81%) relative to the Flap- Saline (83.98%; p<0.0001) and the Flap-BVZ groups (60.50%; p=0.0048). The lowest vascular pedicle patency was observed in the Flap-BVZ group, but the difference relative to the Flap-Saline was not significant (arteries, p=0.0867; veins, p=0.9999). A significant difference was observed in the occurrence of necrosis (p=0.0010), which was higher in the histological samples of the Graft (87.50%) and the Flap- BVZ (60.00%) relative to the Flap-Saline Group (0%). Inflammation occurred less frequently in the Flap-Saline (33.33%) compared to the Graft (87.5%) and Flap- BVZ group (70.00%), but the difference did not reach significance (p=0.0588). No significant differences emerged in the occurrence of hemorrhage or intraluminal thrombosis. Conclusion: The increase in inflammation, decrease in patency and reduction of viable area, though not significant, are in line with the histological analysis and call for further research on the potential adverse effects of the drug.
Introdução: Bevacizumabe é um dos fármacos mais utilizados no tratamento do câncer. Existem evidências de que drogas antiangiogênicas reduzem a taxa de sobrevivência dos retalhos, porém não está claro se isso se aplica ao bevacizumabe. Investigamos o efeito de bevacizumabe na viabilidade de retalhos livres em ratos. Método: Os animais foram randomizados em três grupos. O grupo Enxerto recebeu injeção intravenosa de soro fisiológico 0,9% (SF 0,9%) e foi submetido a uma enxertia de pele total. Os grupos Retalho-SF e Retalho-BVZ foram submetidos a retalhos inguinais livres e receberam injeções intravenosas, respectivamente, de SF 0,9% e Bevacizumabe. Resultados: O grupo Enxerto apresentou menor percentual de área de retalho viável (22,81%) em relação ao grupo Retalho-SF (83,98%; p<0,0001) e Retalho-BVZ (60,50%; p=0,0048). Os pedículos do grupo Retalho-BVZ apresentaram menor patência, mas a diferença em relação ao grupo Retalho-SF não foi significante (artérias, p=0,0867; veias, p=0,9999). A ocorrência de necrose foi significativamente maior nos grupos Enxerto (87,50%) e Retalho-BVZ (60,00%) em relação ao grupo Retalho-SF (0%) (p=0,0010). A ocorrência de inflamação foi menor no grupo Retalho-SF (33,33%) em relação aos grupos Enxerto (87,5%) e Retalho-BVZ (70,00%), porém essa análise não atingiu significância (p=0,0588). Não houve diferenças significantes na ocorrência de hemorragia ou trombose intraluminal entre os grupos. Conclusão: O aumento da inflamação, redução da patência e das áreas viáveis dos retalhos, apesar de não significantes, corroboram com efeitos deletérios do bevacizumabe evidenciados na análise histológica e demandam futuros estudos dos potenciais efeitos adversos da droga.
ABSTRACT
Aim of the study: The present study aimed to study histological features of different organs before and after treatment of diabetes by using avocado extract in rats. Materials and methods: Hot aqueous extraction of avocado was performed. Forty male rats (weighted 140–190g) were used in this study. Following the time of acclimatization, the animals had an overnight fast of 18 hours before being prepped for alloxan monohydrate-induced diabetes. Before and after induction, measurements of the animals’ body weights and blood glucose levels were made. However, rats received an IP injection of alloxan 150 mg/kg bw. Following that, the rats’ blood glucose levels were tracked every day for 3 weeks to establish a stable levels of blood glucose. The animals were divided into 4 groups: Group 1 got water as a non-induced (negative control) condition. Alloxan-induced rats in Group 2 received water as a positive control. Group 3: Alloxan-induced and aqueous extract-treated animals and Group 4 was only given a 40 g/L dose of the aqueous extract of avocado. Pancreas, livers, as well as kidneys from control, alloxanized, and treated rats were taken at different times, processed and utilized for histological examination after being preserved in 10% formaldehyde till processing and staining. Results: The current results showed a significant difference between different groups especially in G3 at different weeks. However, rats in G2 exhibited depleted islet cells and regions of cell necrosis. The tiny, preserved islet cells (PIL) in diabetic rats treated with extract after 1 week (G3) were an improvement as compared with rats at G2. As the days advanced, more improvements were seen in the pancreatic architecture of the rats treated with extract, including the presence of more noticeable islet cells and exocrine cells. As seen by the intact pancreatic islet in G3, caused the healing of the pancreatic tissue after 3 weeks of treatment by extracts. Alloxanized rats (G2) showed the presence of cell necrosis as well as infiltrations of inflammatory cells. However, as the course of therapy continued, it became clear that the tissue architecture had improved, and more glomeruli were seen as well as fewer inflammatory cells (G3). Livers of rats in (G2) showed visible cell necrosis, when compared to the histology of G1 and G4. After receiving medication, rats in group G3 had compact, healthy liver tissues after three weeks. In conclusion, the pancreas, kidneys, and liver were all protected by the avocado extract and showed enhancement in the histological architecture and glucose levels.
ABSTRACT
Aim: The effect of Solanum aethiopicum (SA) on the haematological indices of Wistar rats was investigated in this study. Methodology: A total of 20 male Wistar rats with an average 172.45±0.15 g were distributed into four groups (A – D) and allowed to acclimatize for two weeks. Group A served as the control, while groups B, C, and D were given aqueous extracts of SA at doses of 75 mg/kg, 150 mg/kg, and 225 mg/kg per body weight, respectively, every 48 hours for 30 days. After the exposure period, a final evaluation and sacrifice of the rats was performed. Blood sample collection was carried for full blood count and blood film preparation. Results: The result of this study showed that leaf extract of Solanum aethiopicum caused a significant increase in white blood cells (18.18±0.78 - 27.08±2.68 x 103/?l), especially lymphocytes (13.58±2.48 - 30.95±4.65 x 103/?l) in group of rats when compared to control. On the contrary, there was a non-significant reduction in red blood cells (7.78±0.04 - 7.19±0.45 x 106/?l), hemoglobin (16.92±0.62 - 14.55±0.95 g/dl), haematocrit (41.49±0.29 - 38.38±1.68 %), mean corpuscular hemoglobin (21.71±0.91 - 20.30±0.10 ?g) when compared to the control. Platelet (451.25±87.25 - 724.75±249.25 x 103/?l) and Plateletcrit (0.36±0.07 - 0.50±0.17 %) was significantly higher in treated group, while mean platelet volume (8.21±0.31 - 6.98±0.07 ?m3) and platelet distribution width (18.68±1.38 - 15.93±0.73 %) was low when compared with control. Conclusion: The current study has demonstrated that the leaves of Solanum aethiopicum may be safe to consume in regulated amount, as it has been shown to boost blood indices. These plant extracts may be utilized as a blood promoting potentials as it has been shown to strengthens the body's immune system particularly cell-mediated immunity, have no hemotoxic impact on the red blood cell and its indices and improve the ability for the body to repair itself as seen from the platelet count and its indices.
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Abstract Osteoporosis can affect a significant part of the population and fractures are the most common complications associated with this disease, leading to high public health costs. Thus, the prevention of fractures is relevant to individuals with signs and symptoms as well as to the health system. Postmenopausal osteoporosis has been associated with oxidative stress, emphasizing the importance of an efficient defense system to maintain bone health. Lycopene is a carotenoid with antioxidant properties that may stimulate osteoblastogenesis and inhibit osteoclastogenesis. The purpose of this investigation was to analyze the influence of lycopene in the bone neoformation of calvaria defects in ovariectomized rats utilizing the concentration of 45 mg/kg. Wistar Hannover female rats were divided into ovariectomized and sham groups. The ovariectomized animals received 45 mg/kg lycopene (OvxL) or water (Ovx) by daily gavage the day after ovariectomy/sham surgery for 16 weeks. Twelve weeks after ovariectomy, there were performed 5-mm calvaria defects followed by euthanasia after 4 weeks. Samples of bone tissue were collected to perform morphological and morphometrical analysis of the neoformed bone area, and percentage with Software Image J. Morphological evaluation showed mature bone with more osteocytes in the group OVxL when compared to the other groups. The morphometrical analysis demonstrated a significant increase of bone neoformation in the group OvxL (p<0.05). The data obtained suggest that lycopene benefits bone repair in the absence of estrogenic hormones.
Resumo A osteoporose afeta grande parte da população e as fraturas são as complicações mais importantes relacionadas a essa doença, gerando altos gastos para o poder público. Dessa forma, a prevenção de fraturas decorrentes da osteoporose torna-se relevante tendo em vista que gera benefícios tanto para o indivíduo acometido pela doença quanto para o sistema de saúde. A osteoporose pós menoupasa tem sido associada ao estresse oxidativo, portanto, um eficiente sistema de defesa antioxidante é primordial para a manutenção da saúde óssea. O licopeno é um carotenoide antioxidante que aparentemente estimula a osteoblastogênese e inibe a osteoclastogênese. O objetivo deste estudo foi analisar a influência do licopeno na neoformação óssea em defeitos de calvária em ratas ovariectomizadas utilizando a concentração de 45 mg/kg. Foram utilizados 15 ratas Wistar Hannover pesando aproximadamente 200g, sendo que 10 animais foram submetidos à ovariectomia bilateral e 5 (Grupo Sham) foram submetidos à simulação da cirurgia de ovariectomia bilateral. Os animais ovariectomizados foram divididos aleatoriamente em 2 grupos: Ovariectomizado (Ovx) e Ovariectomizado Licopeno (OvxL) que receberam água e licopeno respectivamente, por sonda gástrica, diariamente. As administrações iniciaram-se no dia seguinte à cirurgia de ovariectomia e/ou da exposição dos ovários e foram mantidas por 120 dias, data de realização da eutanásia. O grupo Sham recebeu água diariamente. Noventa dias após a ovariectomia bilateral foram confecionados defeitos ósseos nas calvárias de todos os animais e após trinta dias as ratas foram eutanasiadas. As amostras de tecido ósseo foram coletadas e foi realizado o processamento para a obtenção das lâminas histológicas. Foram realizadas as análises morfológicas e morfométrica, onde foi estimada a área (mm2) e porcentagem (%) relativa de osso neoformado utilizando o Software Image J. A avaliação morfológica evidenciou a ação benéfica do licopeno pois os animais que receberam esse antioxidante apresentaram um tecido ósseo mais maduro, com maior presença de osteócitos quando comparados aos demais grupos. Por meio das análises morfométricas verificou-se maior neoformação óssea para os animais que receberam o licopeno (p<0,05). Diante dos resultados obtidos, concluiu-se que o licopeno na concentração de 45 mg/Kg teve efeito benéfico no processo de reparação, promovendo significante formação óssea frente à ausência de hormônios estrogênicos.
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Introduction: Phenylhydrazine has been used in many studies to evaluate its modulatory effects in various biochemical parameters in whole blood and red blood cell lysate. Jatropha tanjorensis Euphorbiaceae have high antioxidants properties; its leaves phytochemical analysis shows the presence of flavonoids, tanins, terpenoids, saponis. This study investigated the ameliorative effects of Jatropha tanjorensis Euphorbiaceae on phenylhydrazine induced haematological alterations in albino Wistar rats. Materials and Methods: Wistar rats of both sexes (180-200g) were divided into 4 groups (n=5). Group 1 received rat chow; Group 2 received (200 mg/kg) of J. tanjorensis orally. Group 3 received phenylhydrazine only (10 mg/kg). Group 4 received phenylhydrazine (10 mg/kg) + J. tanjorensis (250 mg/kg). All animals were allowed free access to clean drinking water and normal rat chow ad libitum for 35 days. After which animals were sacrificed and blood samples collected for biochemical analysis. Results: Results obtained showed that phenylhydrazine induced normochromic anemia with significant increase in white blood cell count, and neutrophil counts, eosinophils (insignificant) count with a significant reduction in lymphocyte count. However, J. tanjorensis extract reversed the adverse haematological changes induced by phenylhydrazine. Conclusion: In conclusion, Jatropha tanjorensis Euphorbiaceae demonstrated antioxidant, anti-inflammatory, and anti-thrombotic effects and reversed the haematological alterations brought upon by phenylhydrazine administration.
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This research investigated the effect of Andrographis paniculata (AP) on oxidative stress following indomethacin-induced gastric ulcer in rats. A total of 20 male albino Wistar rats (150-180g) used for this study were grouped into four (n=5): 1, Negative Control; 2, Positive Control and 3, test group treated with normal chow, 20mg/kg indomethacin, 20 mg/kg indomethacin plus omeprazole at 20mg/kg and 20mg/kg indomethacin plus AP at 16.7 mg/kg respectively. After treatment period, estimation of oxidative stress parameters was carried out on the animals. The LD50 of aqueous extract of AP was 50mg/kg bw. Body weight change was significantly reduced in omeprazole treated group compared to all other groups while extract treated group had significantly increased body weight change. There was a significant increase in malondialdehyde (MDA) level of ulcer untreated group compared to other groups. The two treated groups had significantly reduced MDA compared to ulcer untreated group. There was a significant decrease in the levels of GPx and SOD of ulcer untreated group compared to control. Meanwhile, these were significantly increased in extract and omeprazole treated groups compared to ulcer untreated group. Catalase was significantly increased in all three groups when compared to control but its level was significantly increased in extract treated group compared to ulcer untreated and omeprazole treated groups. From this study, AP has proved to protect against oxidative stress implicated in the pathogenesis of ulcer. If this result is applicable to humans, further research and use of AP in ameliorating debilitating consequences of peptic ulcer should be encouraged.
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El objetivo del presente trabajo fue determinar el efecto regenerador gástrico del consumo de Petroselinum sativum L. (perejil) en ratas con gastritis inducida por etanol. Se realizó un estudio analítico, experimental clásico, transversal, prospectivo. Se trabajó con 36 ratas Wistar machos (250 ± 30 g.p.c.) distribuidas aleatoriamente en 6 grupos (n=6). Los grupos II-VI fueron sometidos a ayuno de 24 horas para inducirles úlcera gástrica administrándoles 10 mL/kg.p.c. de etanol al 70% vía orogástrica. Después de una hora, se procedió a sacrificar al grupo II para observar el daño ulceroso en el estómago. Después, se elaboró el extracto acuoso de hojas frescas de perejil (EAHP) y se administró a los demás grupos el siguiente tratamiento por vía orogástrica durante 3 días: grupo III, 10 mL/kg.p.c. de solución de NaCl al 0,9%; y EAHP a los grupos IV-VI (150, 300 y 600 mg/kg.p.c., respectivamente). Enseguida, las ratas fueron sometidas a ayuno de 24 horas para luego ser sacrificadas por desnucamiento. Posteriormente, se les realizó una laparotomía para la extracción del estómago. El EAHP generó mayor producción de moco gástrico en las dosis de 300 mg/kg.p.c. con 78,03% y de 600 mg/kg.p.c. con 80,52% (p<0,05). Esto concordó con lo observado histológicamente en la mucosa gástrica, mostrando solo signos de inflamación de la submucosa en los grupos que consumieron EAHP (IV-VI), en comparación con necrosis fibrinoide de los grupos que no lo consumieron (II y III). En conclusión, el consumo de EAHP tiene un efecto regenerador gástrico en ratas con gastritis inducida por etanol.
Our objective is to determine the gastric regenerative effect of Petroselinum sativum L. (parsley) consumption in rats with ethanolinduced gastritis. We developed an analytical, experimental, classical, cross-sectional, prospective study. We worked with 36 male Wistar rats (250 ± 30 g.p.c.) randomly distributed into 6 groups (n=6). Groups II-VI were subjected to a 24-hour fast to induce gastric ulcer by administering 10 mL/kg.p.c. of 70% ethanol via orogastric. After one hour, group II was sacrificed to observe the ulcerative damage in the stomach. Afterward, the aqueous extract of fresh parsley leaves (EAHP) was prepared, and the following treatment was administered to the other groups through the orogastric route for 3 days: group III, 10 mL/kg.p.c. 0.9% NaCl solution; and EAHP to groups IV-VI (150, 300, and 600 mg/Kg.p.c., respectively). The rats were then fasted for 24 hours before being sacrificed by breaking their necks. Subsequently, a laparotomy was performed to extract the stomach. The EAHP generated greater production of gastric mucus in the doses of 300 mg/kg.p.c. with 78.03% and 600 mg/kg.p.c. with 80.52% (p<0.05). This was consistent with what was observed histologically in the gastric mucosa, showing only signs of inflammation of the submucosa in the groups that consumed EAHP (IV-VI), compared with fibrinoid necrosis in the groups that did not consume it (II and III). In conclusion, the consumption of EAHP has a gastric regenerative effect in rats with ethanol-induced gastritis.
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Effort to explore the adverse effect of the plant, Momordica charantia on mammals has remained inadequate despite previous attempt by earlier investigators. More glaring is the paucity of information on the histomorphological effect of the plant’s aqueous leaf extract hence the need to determine possible alteration of tissue structures in reproductive organs of adult Wistar rats which may affect their functions. This study aimed at determining the effect of Momordica charantia aqueous leaf extract (MCALE) on the reproductive organs of experimental adult Wistar rats. Materials and Methods: Twenty five rats (male and female) weighing 180-200g were randomly divided into five (5) groups of five rats each. The experimental groups, A to D were fed on standard diet and administered with 100, 200, 400 and 800 mg/kg body weight /day of MCE orally using gavage for 30 days. Rats in the control groups were fed on standard diet and physiological saline orally. Organs were harvested, fixed in 10% neutral buffered formalin (ovaries) and Bouin’s fluid (testes), embedded in molten paraffin wax, sectioned with a rotary microtome and stained with the haematoxylin and eosin technique. Stained slides were examined using the Olympus microscope. Results: Sections of ovaries administered 100 mg/kg of the extract showed vesicular spaces in corpus luteum and enlarged blood vessels. Sections treated with 200 mg/kg revealed follicular cyst and mild vacuolation of zona granulosa. Sections of the ovaries administered 400 mg/kg revealed degenerative changes, follicular cyst, mild vacuolation and reduction of zona granulosa layer while those treated with 800 mg/kg showed severe vacuolation of the zona granulosa layer. Conclusion: Momordica charantia caused histomorphological changes in ovaries of Wistar rats which could cause hormonal imbalance and infertility in females. No histomorphological changes were observed in male testes.
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Abstract Objective To evaluate the effects of hydrolyzed collagen and collagen peptide in the treatment of superficial chondral lesions in rats. Method This research employed 18 Rattus norvegicus. A single intraarticular infiltration of sodium iodoacetate (2 mg solution) through the patellar ligament induced joint damage in previously anesthetized animals. We divided the animals into three groups: a control group, a collagen peptide group, and a hydrolyzed collagen group. Treatment consisted of oral administration of collagen peptide or hydrolyzed collagen for 30 days. Afterwards, we euthanized the animals and studied the joint chondral changes. We evaluated the results according to the chondrocyte clusters count and a histological evaluation, as per Pritzker et al. Results There was no statistical significance in injury stages between the control, hydrolyzed collagen, and collagen peptide groups (p= 0.11). Regarding scores, there was a statistical significance between the groups treated with hydrolyzed collagen and collagen peptide (p< 0.05), but not in comparison with the control group. Conclusion The proposed treatments of the induced chondral lesion with the oral administration of hydrolyzed collagen or collagen peptides were effective, resulting in lesion stabilization or regression, and warranting further experimental research to understand and improve the primary outcome of this study.
Resumo Objetivo Avaliar os efeitos do colágeno hidrolisado e do peptídeo de colágeno no tratamento de lesões condrais superficiais de ratos. Método Foram utilizados 18 Rattus norvegicus nesta pesquisa. O dano articular foi induzido por uma única infiltração intra-articular de iodoacetato de sódio (solução 2 mg), injetada através do ligamento patelar da articulação dos animais previamente anestesiados. Os animais foram distribuídos em três grupos: grupo controle, grupo peptídeo de colágeno e grupo colágeno hidrolisado. O tratamento foi realizado por 30 dias com a administração via oral do peptídeo de colágeno ou do colágeno hidrolisado. Posteriormente, foi realizada a eutanásia dos experimentos e seguiu-se para o estudo das alterações condrais articulares. Os resultados foram avaliados conforme contagem de condrócitos por cluster e através da avaliação histológica segundo Pritzker et al. Resultados Ao observar os estágios de lesão, não foi observada significância estatística entre os grupos controle, colágeno hidrolisado e peptídeo de colágeno (p= 0,11). Ao observar os escores, houve significância estatística na comparação do grupo tratado com colágeno hidrolisado e o grupo peptídeo colágeno (p< 0,05), porém sem diferença estatística em relação ao grupo controle. Conclusão Os tratamentos propostos da lesão condral induzida com uso de colágeno hidrolisado ou peptídeos de colágeno via oral mostraram-se eficazes, com estabilização ou regressão da lesão apresentada em ratos, merecendo novas pesquisas experimentais com o intuito de compreender e melhorar o desfecho primário deste trabalho.
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Animals , Rats , Collagen , Knee Injuries/therapyABSTRACT
Effects of aqueous seed extracts of Sphenostylis stenocarpa on the reproductive indices of male rats were investigated. A total of 104 adult rats were used for the experiment, and were divided into 4 groups (group A – D) and replicated in triplicate. Group A served as the normal control, while groups B, C and D received three graded doses (800mg/kg, 1200mg/kg and 1600mg/kg) of the extracts, respectively, by oral intubation. The gonad characteristics, sperm parameters and hormonal analyses of the male rats were determined using standard procedures. These were ascertained prior to the commencement of treatment, and on weekly basis. Data were analyzed statistically using SPSS and R software at 95% confidence interval. An overall dose and time dependent showed significant differences in the mean weekly gonad characteristics of the male rats in the treatment groups when compared with the control. There was a significant reduction (p < 0.05) in the body weights of the male rats, but a significant increase (P < 0.05) in the testes weights, gonad somatic index, sperm count and sperm motility in the rats. The gonadal hormone testosterone, responded to the plant extracts, while follicle-stimulating and luteinizing hormones were largely undetected. There were significant increases in the testosterone levels of all the treated rats. Conclusively, aqueous seed extracts of Sphenostylis stenocarpa seems to possess ability to enhance reproductive health in male rats.
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Abstract Biological activity of boron-containing compounds (BCCs) has been well-known. Growing interest and numerous applications for BCCs have been reported. Boron and boron-containing acids show low acute toxicity in mammals but data on halogenated boroxine (HB) - dipotassium-trioxohydroxytetrafluorotriborate, K2(B3O3F4OH) acute toxicity have not been reported before. This compound, characterized as a potential therapeutic for skin changes, exhibits no observable genotoxicity in doses lower that 0.1 mg/ml in vitro and 55 mg/kg in vivo. It has also been confirmed as an antitumour agent both in vitro and in vivo as well as an inhibitor of enzymes involved in antioxidant mechanisms. The aim of this study was to assess the acute toxicity of HB and to determine the maximum tolerated dose as well as a dose free of any signs of toxicity in different test organisms. Acute toxicity of HB was tested in Sprague-Dawley and Wistar rats and BALB/c mice after single parenteral application of different doses. We determined doses free of any sign of toxicity and LD50 after single dose administration. LD50 of HB ranges from 63 to 75 mg/kg in different test models, meaning that HB shows moderate toxicity
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Animals , Male , Female , Mice , Rats , Boron/agonists , Toxicity Tests, Acute/instrumentation , Drug Development/instrumentation , Antioxidants/pharmacology , Biological Products/adverse effects , In Vitro Techniques/methodsABSTRACT
Gum Arabic (Acacia nilotica L.) is a respected plant that has many nutrients and curative practices. It hinders, improves, or manages many disorders. The radio-protective activity of Acacia nilotica was investigated against γ-rays-induced testicle damage in rats. Twenty-four rats were correspondingly distributed into 4 groups; control, Acacia nilotica (15mg/kg, daily for 30 days), γ-irradiated (5Gy γ-rays, single dose) and Acacia nilotica plus γ-rays treated groups. The plasma testosterone and total antioxidant status (TAS) were estimated. Lipid peroxidation; malondialdehyde (MDA), reduced glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD), also glutathione peroxidase (GPx), catalase (CAT), tumor necrosis factor-α (TNF-α) with interleukin-1ß (IL-1ß), were determined in the testicle tissues. A testis weight, sperm count and motility, peripheral-blood and bone-marrow micronuclei (PMN and BMN), and frequency of chromosomal aberrations (CAs) were scored. A significant decline in the levels of plasma testosterone with TAS observed in the γ-irradiated rats. The results also showed significantly increased levels of testicle MDA, inflammatory markers, PMN, BMN and CAs frequencies and decrease in testes weight, sperm count and motility and levels of testicle antioxidants markers in gamma irradiated group. All these biochemical and fertility indices results were significantly enhanced in the Acacia nilotica plus γ-rays treated groups. However, the possible alleviate activity of Acacia nilotica on γ-rays-induced testicle injury in rats has not previously conversed, and this is the topic of this study.
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Background Nonalcoholic fatty pancreatitis (NAFP) is one of the metabolic syndrome manifestations that need further studies to determine its molecular determinants and find effective medications. We aimed to investigate the potential effect of benzyl propylene glycoside on NAFP management via targeting the pancreatic cGAS-STING pathway-related genes (DDX58, NFκB1 & CHUK) and their upstream regulator miRNA (miR-1976) that were retrieved from bioinformatics analysis. Methods The rats were fed either normal chow or a high-fat high-sucrose diet (HFHS), as a nutritional model for NAFP. After 8 weeks, the HFHS-fed rats were subdivided randomly into 4 groups; untreated HFHS group (NAFP model group) and three treated groups which received 3 doses of benzyl propylene glycoside (10, 20, and 30 mg/kg) daily for 4 weeks, parallel with HFHS feeding. Results The molecular analysis revealed that benzyl propylene glycoside could modulate the expression of the pancreatic cGAS-STING pathway-related through the downregulation of the expression of DDX58, NFκB1, and CHUK mRNAs and upregulation of miR-1976 expression. Moreover, the applied treatment reversed insulin resistance, inflammation, and fibrosis observed in the untreated NAFP group, as evidenced by improved lipid panel, decreased body weight and the serum level of lipase and amylase, reduced protein levels of NFκB1 and caspase-3 with a significant reduction in area % of collagen fibers in the pancreatic sections of treated animals. Conclusion benzyl propylene glycoside showed a potential ability to attenuate NAFP development, inhibit pancreatic inflammation and fibrosis and reduce the pathological and metabolic disturbances monitored in the applied NAFP animal model. The detected effect was correlated with modulation of the expression of pancreatic (DDX58, NFκB1, and CHUK mRNAs and miR-1976) panel.
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ABSTRACT Objective To assess the effects of enfuvirtide on pregnancy in albino rats and their fetuses. Methods Forty pregnant EPM 1 Wistar rats were randomly allocated into four groups: control (E) (distilled water twice/day), G1 (4mg/kg/day enfuvirtide), G2 (12mg/kg/day enfuvirtide), and G3 (36mg/kg/day enfuvirtide) groups. On the 20th day of gestation, the rats were anesthetized and subjected to cesarean section. Their blood was collected for laboratory analysis, and they were sacrificed. The offspring's fragments of their kidneys, liver, and placentas and the maternal rats' fragments of their lungs, kidneys, and liver were separated in the immediate postpartum period for light microscopy analysis. Results No maternal deaths occurred. In the second week at the end of pregnancy, the mean weight of the G3 Group was significantly lower than that of the G2 Group (p=0.029 and p=0.028, respectively). Analyzing blood laboratory parameters, the G1 Group had the lowest mean amylase level, and the G2 Group had the lowest mean hemoglobin level and the highest mean platelet count. In the morphological analysis, there were no changes in organs, such as the kidneys and liver, in both the maternal rats and offspring. Three maternal rats in the G3 Group had pulmonary inflammation in the lungs. Conclusion Enfuvirtide has no significant adverse effects on pregnancy, conceptual products, or functional alterations in maternal rats.
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Resumen OBJETIVOS: Determinar la repercusión de la diabetes pregestacional, con hiperglucemias moderadas, en el rendimiento reproductivo de la rata, crecimiento, desarrollo y morfología embrionaria en ratas Wistar. MATERIALES Y MÉTODOS: Estudio longitudinal, prospectivo y experimental efectuado en la Unidad de Investigaciones Biomédicas de la Universidad de Ciencias Médicas de Villa Clara, Cuba, en un modelo de diabetes moderada inducida neonatalmente a crías hembras de ratas Wistar de dos días de nacidas mediante la administración subcutánea de 100 mg/kg de peso corporal de estreptozotocina en una única dosis. A los 120 días de nacidas, las ratas de ambos grupos de experimentación (diabético y control) se aparearon con machos sanos. Se determinaron el peso y la glucemia durante la gestación y a los 11.5 días se practicó la cesárea. Se analizaron las variables del rendimiento reproductivo materno y de crecimiento, desarrollo y morfología externa en los embriones. Acorde con los desenlaces se utilizaron pruebas no paramétricas para el análisis de las variables cuantitativas y la prueba de χ2 para las variables cualitativas. RESULTADOS: La hiperglucemia moderada pregestacional provocó modificaciones en la ganancia de peso de la madre, la cantidad de reabsorciones, sitios de implantación, pérdidas preimplantación y eficiencia de implantación, así como en la morfología, talla y cantidad de somitas en los embriones. CONCLUSIONES: La diabetes moderada pregestacional alteró el rendimiento reproductivo materno y el crecimiento y desarrollo intrauterino de la descendencia en etapa embrionaria. La embriopatía diabética se manifestó, además, con malformaciones del sistema nervioso central.
Abstract OBJECTIVES: Diabetes mellitus is one of the most frequent disorders of pregnancy with adverse consequences for the mother and a high risk of diabetic embryopathy in the offspring. The objective of the research was to determine the effect of pregestational diabetes with moderate hyperglycemia on maternal reproductive performance, growth, development and embryonic morphology in Wistar rats. MATERIALS AND METHODS: Longitudinal, prospective and experimental study carried out at the Biomedical Research Unit of the University of Medical Sciences of Villa Clara, Cuba. A model of neonatally induced moderate diabetes was used in female Wistar rat pups two days old, by subcutaneous administration of 100 mg/kg of body weight of streptozotocin in a single dose. At 120 days after birth, rats from both experimental groups (diabetic and control) were mated with healthy males. Weight and glycemia were determined during pregnancy and at 11,5 days the cesarean section was performed. The variables of maternal reproductive performance and of growth, development and external morphology in the embryos were analyzed. According to the results, non-parametric tests were used for the analysis of the quantitative variables and the Chi-square test for the qualitative variables. RESULTS: Moderate pregestational diabetes caused changes in maternal weight gain, number of resorptions, implantation sites, preimplantation loss, and implantation efficiency, as well as in morphology, size, and number of somites in embryos. CONCLUSIONS: Moderate pregestational diabetes altered maternal reproductive performance and intrauterine growth and development of embryonic offspring. Diabetic embryopathy was also manifested by malformations of the central nervous system.
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A doença de Chagas causada pelo parasita Trypanosoma cruzi acomete milhões de pessoas no mundo e não conta com um medicamento de ação efetiva para o seu tratamento etiológico. As drogas disponíveis, o nifurtimox e o benznidazol possuem índices de cura baixos com efeitos colaterais e toxidade que dificultam a adesão dos pacientes à terapia. Este fato impulsiona a busca por alternativas de tratamento que sejam mais efetivas e menos agressivas. Sendo assim, este trabalho teve como objetivo a avaliação dos efeitos clínicos apresentados por Rattus norvergicus infectados por T. cruzi e tratados com soluções ultradiluídas de Lycopodium clavatum ou Phosphorus. O estudo envolveu 93 ratos com quarenta e cinco dias de idade infectados intraperitonealmente com 5x106 formas tripomastigotas sanguíneos da cepa Y de T. cruzi, distribuídos nos grupos: Sadio SD (n=13) - controle não infectado e não tratado, grupo CI (n=27) - controle infectado e tratado com solução hidroalccólica 7% (etanol água), grupo LY diluição 1:1x1026 (n=27) - infectado e tratado com Lycopodium, grupo PH diluição 1:1x1026 (n=26) - infectado e tratado com Phosphorum. Os animais foram avaliados clinicamente através dos parâmetros peso, temperatura, consumo de água e ração, quantidade de excretas, diâmetro e comprimento intestinal, aspecto da pelagem e consistência das fezes. Este estudo mostrou que os parâmetros utilizados foram importantes para a definição clínica da infecção de Rattus novergicus, linhagem Wistar pelo T. cruzi. Mostrou que os medicamentos LY e PH apresentam efeitos benéficos na evolução da clínica dos animais tratados. A utilização de Lycopodium clavatum e Phosphorus diluídos na proporção de 1:1x1026, apresentaram efeitos diferentes. Oito e seis parâmetros de quatorze analisados mostraram efeitos positivos para LY e PH, respectivamente. Os parâmetros consumo de água e ração, quantidade de excretas, diarreia, alopecia difusa e comprimento intestinal apresentaram diferenças significativas em relação ao controle infectado mostrando que mais estudos são necessários com o uso de medicamentos ultradiluídos na infecção pelo T. cruzi.
Chagas disease caused by the parasite Trypanosoma cruzi affects millions of people worldwide and does not have an effective drug for its etiological treatment. The available drugs, nifurtimox and benznidazole, have low cure rates with side effects and toxicity that make it difficult for patients to adhere to therapy. This fact drives the search for treatment alternatives that are more effective and less aggressive. Therefore, this work aimed to evaluate the clinical effects presented by Rattus norvergicus infected by T. cruzi and treated with ultradiluted solutions of Lycopodium clavatum or Phosphorus. The study involved 93 forty five day old rats intraperitoneally infected with 5x106 blood trypomastigotes forms of the Y strain of T. cruzi, distributed in the following groups: Healthy SD (n=13) - non-infected and untreated control, CI group (n =27) - infected control and treated with 7% hydroalcoholic solution (ethanol water), LY group dilution 1:1x1026 (n=27) - infected and treated with Lycopodium, PH group dilution 1:1x1026 (n=26) - infected and treated with Phosphorum. The animals were clinically evaluated through the parameters weight, temperature, water and feed consumption, amount of excreta, intestinal diameter and length, coat appearance and feces consistency. This study showed that the parameters used were important for the clinical definition of infection of Rattus novergicus, Wistar lineage by T. cruzi. It showed that LY and PH drugs have beneficial effects on the clinical evolution of treated animals. The use of Lycopodium clavatum and Phosphorus diluted in the ratio of 1:1x1026, showed different effects. Eight and six parameters out of fourteen analyzed showed positive effects for LY and PH, respectively. The parameters water and feed consumption, amount of excreta, diarrhea, diffuse alopecia and intestinal length showed significant differences in relation to the infected control, showing that more studies are needed with the use of ultradiluted drugs in T. cruzi infection.
La enfermedad de Chagas causada por el parásito Trypanosoma cruzi afecta a millones de personas en todo el mundo y no cuenta con un fármaco eficaz para su tratamiento etiológico. Los fármacos disponibles, nifurtimox y benznidazol, presentan bajas tasas de curación con efectos secundarios y toxicidad que dificultan la adherencia terapéutica de los pacientes. Este hecho impulsa la búsqueda de alternativas de tratamiento más eficaces y menos agresivas. Por lo tanto, este trabajo tuvo como objetivo evaluar los efectos clínicos presentados por Rattus norvergicus infectados por T. cruzi y tratados con soluciones ultradiluidas de Lycopodium clavatum o Fósforo. En el estudio participaron 93 ratas de cuarenta y cinco días de edad infectadas intraperitonealmente con 5x106 formas tripomastigotes sanguíneas de la cepa Y de T. cruzi, distribuidos en los siguientes grupos: SD sano (n=13) - control no infectado y no tratado, grupo CI (n =27) - control infectado y tratado con solución hidroalcohólica al 7% (etanol - agua), grupo LY dilución 1:1x1026 (n=27) - infectado y tratado con Lycopodium, grupo PH dilución 1:1x1026 (n=26) - infectado y tratado con Phosphorum. Los animales fueron evaluados clínicamente mediante los parámetros peso, temperatura, consumo de agua y pienso, cantidad de excrementos, diámetro y longitud intestinal, aspecto del pelaje y consistencia de las heces. Este estudio demostró que los parámetros utilizados eran importantes para la definición clínica de la infección de Rattus novergicus, linaje Wistar por T. cruzi. Demostró que los fármacos LY y PH tienen efectos beneficiosos en la evolución clínica de los animales tratados. El uso de Lycopodium clavatum y Phosphorus diluidos en la proporción de 1:1x1026, mostró efectos diferentes. Ocho y seis parámetros de los catorce analizados mostraron efectos positivos para LY y PH, respectivamente. Los parámetros consumo de agua y pienso, cantidad de excretas, diarrea, alopecia difusa y longitud intestinal mostraron diferencias significativas en relación al control infectado, mostrando que son necesarios más estudios con el uso de fármacos ultradiluidos en la infección por
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Resumo Fundamento O treinamento intervalado de alta intensidade (HIIT) tem sido sugerido como alternativa ao treinamento contínuo (TC) em indivíduos com diabetes mellitus (DM) devido à sua curta duração e potencial para melhorar a adesão ao exercício. No entanto, dados sobre seu impacto sobre a variabilidade da frequência cardíaca (VFC) são escassos. Objetivos Avaliar e comparar os efeitos do HIIT e TC sobre a capacidade no exercício, VFC e corações isolados em ratos diabéticos. Métodos Animais diabéticos (estreptozotocina intravenosa, 45 mg.kg -1 ) e controles (C) realizaram 20 sessões de TC (5 dias/semana, 50 min, por quatro semanas) em esteira (70% da capacidade máxima de exercício) ou HIIT (ciclos de 1:1min a 50% e 90% da capacidade máxima de exercício). A VFC foi avaliada por eletrocardiograma contínuo, e a função cardíaca foi avaliada em corações isolados perfundidos. Para a análise dos dados, utilizamos a matriz do modelo linear generalizado de covariância multivariada ou o teste one-way ANOVA seguido pelo teste de Tukey, considerando um valor de p<0,05 como significativo. Resultados A capacidade de exercício (m/min) foi maior no grupo submetido ao HIIT [DM-HIIT: 36,5 (IIQ 30,0-41,3); C-HIIT: 41,5 (37,8-44,5), ambos n=10) em comparação ao grupo submetido ao TC [DM-TC: 29,0 (23,8-33,0); C-TC: 32,0 (29,5-37,0), ambos n=10) (p<0,001). A frequência cardíaca (bpm) foi mais baixa no grupo DM em comparação aos controles (p<0,001) tanto in vivo (DM-HIIT: 348±51, C-HIIT:441±66, DM-TC:361±70, C-TC:437±38) como nos corações isolados. Não houve diferenças na VFC entre os grupos. Os valores máximos e mínimos de dP/dt foram reduzidos no DM, com exceção da +dP/dt no grupo DM-HIIT vs. C-HIIT (diferença média: 595,5±250,3, p=0,190). Conclusão O HIIT de curto prazo promoveu melhora superior no desempenho no exercício em comparação ao TC, sem causar mudanças significativas na variabilidade da frequência cardíaca.
Abstract Background High-intensity interval training (HIIT) has been suggested as an alternative for continuous training (CT) in people with diabetes mellitus (DM) due to its short duration and potential to improve adherence to exercise. However, data on its impact on heart rate variability (HRV) are scarce. Objectives To assess and compare the effects of HIIT and CT on exercise capacity, HRV and isolated hearts in diabetic rats. Methods DM (intravenous streptozotocin, 45 mg.kg -1 ) and control (C) animals performed 20 sessions (5 days/week, 50 min, for 4 weeks) of CT on a treadmill (70% of maximal exercise capacity) or HIIT (cycles of 1:1min at 50% and 90% of maximal exercise capacity). HRV was assessed by continuous electrocardiogram, and cardiac function assessed in isolated perfused hearts. For data analysis, we used the framework of the multivariate covariance generalized linear model or one-way ANOVA followed by Tukey's test, considering p<0.05 as significant. Results Higher exercise capacity (m/min) was achieved in HIIT (DM-HIIT: 36.5 [IQR 30.0-41.3]; C-HIIT: 41.5 [37.8-44.5], both n=10) compared to CT (DM-CT: 29.0 [23.8-33.0]; C-CT: 32.0 [29.5-37.0], both n=10) (p<0.001). Heart rate (bpm) was lower in DM compared to controls (p<0.001) both in vivo (DM-HIIT:348±51, C-HIIT:441±66, DM-CT:361±70, C-CT:437±38) and in isolated hearts. There were no differences in HRV between the groups. Maximum and minimal dP/dt were reduced in DM, except +dP/dt in DM-HIIT vs. C-HIIT (mean difference: 595.5±250.3, p=0.190). Conclusion Short-term HIIT promotes greater improvement in exercise performance compared to CT, including in DM, without causing significant changes in HRV.