Experimental model of nephropathy associated with diabetes mellitus in mice

Purpose: Nontransmissible chronic diseases, such as diabetes mellitus (DM) and nephropathy, affect a significant portion of the population, often treated due to injuries that require healing and regeneration. To create an experimental model of associated comorbidities, for healing and regeneration studies, protocols for induction of nephropathy by ischemia and reperfusion (I/R) and induction of DM by injection of streptozotocin (STZ) were associated. Methods: Sixty-four mice (Mus musculus), female, adult, Swiss strain, weighing approximately 20 g, were divided into four groups: G1: control (n = 24), G2: nephropathy group (N) (n = 7), G3, DM (n = 9), and G4: N+DM (n = 24). Arteriovenous stenosis (I/R) of the left kidney was performed as the first protocol. The animals received a hyperlipidemic diet for 7 days after the injection of STZ (150 mg/kg, via i.p.) and an aqueous glucose solution (10%) for 24 h. The animals in the G3 and G4 groups were observed for 14 days before receiving the diet and STZ. The evolution of nephropathy was observed using a urine test strip and the DM, through the analysis of blood glucose with a reagent strip on a digital monitor. Results: The ischemic induction protocols of nephropathy and DM with STZ, associated, were sustainable, low-cost, and without deaths. There were alterations compatible with initial renal alterations, in the first 14 days, such as increased urinary density, pH alteration, presence of glucose, proteins and leukocytes, when compared to the control group. DM was confirmed by the presence of hyperglycemia 7 days after induction and its evolution after 14 days. The animals in the G4 group showed constant weight loss when compared to the other groups. It was possible to observe morphological alterations in the kidneys submitted to I/R, regarding coloration, during surgery and after the end of the observation period, in the volume and size of the left kidney, when compared to the contralateral kidney. Conclusion: It was possible to induce nephropathy and DM associated in the same animal, in a simple way, confirmed with rapid tests, without losses, providing a basis for future studies.

Physiochemical and nutritional evaluation of whole kumquat fruits powder and its protective effect on thyroid hormones and blood sugar levels in diabetic rats / Avaliação físico-química e nutricional de frutas inteiras de kumquat em pó e seu efeito protetor sobre os hormônios da tireoide e os níveis de açúcar no sangue em ratos diabéticos

Abstract The present study was conducted to evaluate the chemical composition, antioxidant activity and hypoglycemic effects of whole kumquat (Ku) powder in diabetic rats fed a high-fat-high-cholesterol (HFHC) diet. The antioxidant activities were evaluated using stable 1,1-diphenyl 2-picrylhydrazyl (DPPH) free radical scavenging method, 2,2´-azinobis (3-ethyl benzo thiazoline-6-sulphonic acid) radical cation (ABTS) and Ferric reducing antioxidant power (FRAP). Total phenolic content was (51.85 mg GAE/g) and total flavonoid content was (0.24 mg Cateachin Equivalent, CE/g). DPPH and ABTS values were 3.32 and 3.98 mg Trolox equivalent (TE)/g where FRAP value was 3.00 mM Fe2+/kg dry material. A total of 90 albino rats were used in the present study. Rats group were as follows: normal diet; normal treated (2, 4, and 6% Ku.), diabetic rats (non-treated), diabetic + HFHC diet (non-treated), HFHC (non-treated), Diabetic (treated), HFHC (treated) and Diabetic + HFHC (treated). The diets were followed for 8 weeks. Blood samples were collected at the end of the experiment. Serum glucose was recorded and thyroid hormones (T4, Thyroxine and T3, Triiodothyronine) were conducted. Diet supplemented with Kumquat at different concentrations have a hypoglycemic effect and improve the thyroid hormones of both diabetic rats and HFHC diabetic rats.

Resumo O presente estudo foi conduzido para avaliar a composição química, a atividade antioxidante e os efeitos hipoglicêmicos do pó de kumquat (Ku) em ratos diabéticos alimentados com uma dieta rica em gordura e colesterol (HFHC). As atividades antioxidantes foram avaliadas usando o método de eliminação de radicais livres de 1,1-difenil 2-picrilhidrazil (DPPH), 2,2'-azinobis (ácido 3-etilbenzotiazolina-6-sulfônico) radical cátion (ABTS) e antioxidante redutor férrico potência (FRAP). O conteúdo fenólico total foi (51,85 mg GAE / g) e o conteúdo total de flavonoides foi (0,24 mg Cateachin Equivalent, CE / g). Os valores de DPPH e ABTS foram 3,32 e 3,98 mg equivalente de Trolox (TE) / g, em que o valor de FRAP foi de 3,00 mM Fe2 + / kg de material seco. Um total de 90 ratos albinos foi usado ​​no presente estudo. O grupo dos ratos foi o seguinte: dieta normal: tratados normais (2, 4 e 6% Ku.), ratos diabéticos (não tratados), diabéticos + dieta HFHC (não tratados), HFHC (não tratados), diabéticos (tratados), HFHC (tratados) e diabéticos + HFHC (tratados). As dietas foram seguidas por 8 semanas. Amostras de sangue foram coletadas ao final do experimento. A glicose sérica foi registrada e os hormônios tireoidianos (T4, Tiroxina e T3, Triiodotironina) foram conduzidos. A dieta suplementada com kumquat em diferentes concentrações tem um efeito hipoglicêmico e melhora os hormônios tireoidianos tanto de ratos diabéticos quanto de ratos diabéticos com HFHC.

Histopathological examination of the protective effect of intense exercise in apoptotic germ cell damage due to diabetes

Purpose: The aim of this study was to determine the protective and antioxidative effects of intensive exercise on streptozotocin (STZ)-induced testicular damage, apoptotic spermatognial cells death, and oxidative stress. Methods: 36 male Sprague Dawley rats were divided into three groups: control, diabetes, and diabetes+intensive exercise (IE) groups. Testicular tissues were examined histopathologically and antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde (MDA) activity, as well as serum testosterone level, were measured. Results: Seminiferous tubules and germ cells were found to be better in the testis tissue of the intense exercise group than in the diabetes group. Diabetes suppressed antioxidant enzymes CAT, SOD, GPx and testosterone levels were significantly decreased, and increased MDA level in the diabetic group compared to diabetes+IE group (p < 0.001). Following four weeks of treatment, intensive exercise improved the antioxidant defense, significantly decreased MDA activity, and increased testosterone levels in testicular tissue in the diabetic group compared to diabetes+IE group (p < 0.01). Conclusion: STZ-induced diabetes causes damage to the testis tissue. In order to prevent these damages, exercise practice has become very popular nowadays. In present study, our intensive exercise protocol, histological, and biochemical analysis of the effect of diabetes on the testicular tissues is shown.

Pouteria ramiflora leaf extract on emulgel in wound healing activity in diabetic rats / Ação do extrato de folhas de Pouteria ramiflora em emulgel na atividade de cicatrização de feridas em ratos diabéticos

The genus Pouteria has been studied because it presents various activities, among which is its anti-inflammatory potential. The effects of Pouteria ramiflora Carbopol gel on the healing of skin wounds in diabetic rats were evaluated by microscopic imaging. Streptozotocin was administered intraperitoneally in animals that had fasted for 12 hours, a situation confirmed by the glycemic index (> 240 mg dL-1). An excision on the back of the animals was performed and three groups were formed: Control (Gel), Ethanolic extract (Ext) and Gel + extract 2% (Ext+gel); the histopathological evaluation occurred on the 7th, 14th, 21st and 30th days after the post-operative period. The results of the phytochemical prospecting of P. ramiflora extract demonstrated the major presence of phenolic compounds and flavonoids; the assessment of the inflammatory infiltrate on the 7th day was higher on group Ext and Ext+gel when compared to group Control; on the 14th day control and Ext (p<0.05). The quantification of fibroblasts was higher on the 7th day among the three treatments, control and Ext (p<0.05), on the 21st day. Angiogenesis showed a higher number of vessels in Ext+gel group (p<0.05) on the 7th day; in Control, Ext and Ext+gel (p<0.05) on the 14th day; and Control and Ext (p<0.05)on the 21st day. The histopathological results showed that the formulation Ext+gel was efficient in tissue reparation and decrease in inflammatory cells on the diabetic's animals.

O gênero Pouteria apresenta várias aplicações terapêuticas e, dentre elas, grande potencial antiflamatório. Os efeitos do gel de Pouteria ramiflora sobre a cicatrização de feridas na pele de ratos diabéticos foram avaliados pela histomorfometria. A estreptozotocina foi administrada por via intraperitoneal em animais após jejum de 12 horas, a confirmação de indução da diabetes foi confirmada pelo índice glicêmico (> 240 mg dL-1). Foi realizada uma incisão no dorso do animal e foram criados 3 grupos de tratamento: controle (gel carbopol), extrato etanólico (Ext) e Gel + extrato etanólico à 2% (Ext+gel); a avaliação histopatológica foi realizada no 7º, 14º, 21º e 30º dias após o período pós operatório. Os resultados da prospecção fitoquímica dos extratos de P. ramiflora demonstraram majoritariamente a presença de compostos fenólicos e flavonóides; o infiltrado inflamatório avaliado no 7º dia foi maior para animais do grupo controle em relação aos grupos Ext (p<0.05) e Ext+gel 2% (p<0.05); no 14º dia o controle e Exp (p<0.05) apresentaram aumento significativo dos infiltrados inflamatórios. A presença de fibroblastos foi elevada no 7º dia em todos os tratamentos. O processo da angiogênese mostrou um maior número de vasos sanguíneos entre os grupos Ext e Ext+gel (p<0.05) no 7º dia; no 14º dia o grupo controle, Ext (p<0.05), Control e Ext+gel (p<0.05) apresentaram aumento de vascularização, e no 21º dia apenas os grupos controle e Ext (p<0.05). Os resultados histopatológicos mostraram que a formulação gel carbopol + extrato etanólico a 2% foi eficiente na reparação de tecidos e na diminuição de células inflamatórias nos animais diabéticos.

Analysis of high-intensity interval training on bone mineral density in an experimental model of type 2 diabetes

Purpose: To analyze the effect of high-intensity interval training (HIIT) on bone mineral density (BMD) in a model of type 2 diabetes mellitus. Methods: Thirty-two male, adult, 12-week-old rats (Rattus norvegicus), of the Wistar lineage, were used. The animals induced to the experimental model received a high fat diet for 10 days and, after that period, intraperitoneal injection of streptozotocin (40 mg·kg­1), dissolved in 20 mmol·L­1 sodium citrate solution (pH = 4.5). The experimental group of diabetes was formed by the animals that, 48 h after the injection of streptozotocin, had fasting blood glucose > 250 mg·dL­1). The animals were randomly divided into four groups with eight animals each: HIIT experimental diabetes; HIIT control; sedentary experimental diabetes and sedentary control. The animals in the HIIT group performed an aerobic exercise protocol on a treadmill inclined at an angle of 15° to the horizontal, with interspersed intensity. Five weekly sessions, lasting 49 min each, were held for 6 weeks. The analysis of cortical bone density (CBD) and BMD were performed by X-ray images using the In-Vivo Xtreme II/Bruker system. Results: For CBD and BMD, when comparing diabetes and control groups, a significant difference was seen between groups in relation to HIIT (p = 0.007). Animals submitted and not submitted to HIIT in the same group showed a significant difference between groups in relation to diabetes (p < 0.001). Conclusions: The HIIT experimental diabetes group had increased CBD and BMD in comparison with the sedentary experimental diabetes group.

The influence of adipocyte-derived stem cells (ASCs) on the ischemic epigastric flap survival in diabetic rats

ABSTRACT Purpose: To assess the effects of adipocyte-derived stem cell (ASC)-injection on the survival of surgical flaps under ischemia in diabetic rats. Methods: Diabetes was induced in 30 male Wistar rats using streptozotocin (55 mg/kg). After eight weeks, epigastric flap (EF) surgery was performed. The animals were divided into control (CG), medium-solution (MG), and ASC groups. The outcomes were: the survival area (SA), the survival/total area rate (S/TR), and expression levels (EL) of genes: C5ar1, Icam1, Nos2, Vegf-a. Results: In the ASC group, compared to CG, we observed improved flap SA (CG-420 mm2 vs. ASC-720 mm2; p=0.003) was observed. The S/TR analysis was larger in the ASC group (78%) than the CG (45%). This study showed an increase in the Vegf-a EL in the ASC group (2.3) vs. CG (0.93, p=0.0008). The Nos2 EL increased four-fold in the ASC group compared to CG, and C5ar1 EL decreased almost two-fold in the ASC group vs. the CG (p=0.02). There was no difference among the groups regarding Icam1 EL. Compared to the MG, the ASC group had a bigger flap SA (720 mm2 vs. 301 mm2, respectively), a bigger S/TR (78% vs. 32%, p=0.06, respectively) and increased EL of Vegf-a (2.3 vs. 1.3, respectively). No difference between ASC-group and MG was seen regarding Nos2 (p=0.08) and C5ar1 (p=0.05). Conclusions: This study suggests that ASCs increase the survival of EF under IR in diabetic rats.

Combination of cafeteria diet with intraperitoneally streptozotocin in rats. A type-2 diabetes model

ABSTRACT Purpose To develop a model of induction of type-2 diabetes (DM2) by combining low doses of streptozotocin (STZ) and a cafeteria diet. Methods Forty male Wistar rats (200 g) were allocated into four groups: control (non-diabetic, n = 10); STZ 30 mg/kg (diabetic, n = 10); STZ 35 mg/kg (diabetic,n = 10); and STZ 40 mg/kg (diabetic, n = 10). DM2 was induced with a single intraperitoneal injection of STZ after four weeks of cafeteria diet in the three diabetic groups. All animals were evaluated as for anthropometric, and biochemical analyses, as well as liver, kidney and pancreas histological analyses. Results Lower weight gain, higher water intake, higher Lee index, hyperglycemia and modified total protein, urea, alpha-amylase, as well as insulin resistance, hepatic steatosis, pancreas, and kidney injury were observed in animals treated with 35 and 40 mg/kg of STZ. Conclusions The results show that the experimental model using cafeteria diet associated with 35 mg/kg of STZ is a low-cost model and efficient in order to develop DM2, confirmed by the presence of polydipsia, hyperglycemia, altered biochemical tests, insulin resistance and damages to the liver, pancreas and kidney, which is similar to the disease found in humans.

Antiparasitic and immunomodulating effects of nitazoxanide, ivermectin and selenium on Cryptosporidium infection in diabetic mice / Efeitos antiparasitários e imunomodulantes da nitazoxanida, ivermectina e selênio sobre a infecção por Cryptosporidium em camundongos diabéticos

Abstract The present work aims to investigate the antiparasitic and the immunomodulating effects of nitazoxanide (NTZ) and ivermectin (IVC) alone or combined together or combined with selenium (Se), on Cryptosporidium infection in diabetic mice. The results revealed that the combined NTZ and IVC therapy achieved the highest reduction of fecal oocysts (92%), whereas single NTZ showed the lowest reduction (63%). Also, adding Se to either NTZ or IVC resulted in elevation of oocyst reduction from 63% to 71% and from 82% to 84% respectively. All treatment regimens, with the exception of NTZ monotherapy, showed a significant improvement in the intestinal histopathology, the highest score was in combined NTZ and IVC therapy. The unique results of immunohistochemistry in this study showed reversal of the normal CD4/CD8 T cell ratio in the infected untreated mice, however, following therapy it reverts back to a normal balanced ratio. The combined (NTZ+ IVC) treatment demonstrated the highest level of CD4 T cell expression. Taken together, NTZ and IVC combined therapy showed remarkable anti-parasitic and immunostimulatory effects, specifically towards the CD4 population that seem to be promising in controlling cryptosporidiosis in diabetic individuals. Further research is required to explore other effective treatment strategies for those comorbid patients.

Resumo O presente trabalho tem como objetivo investigar os efeitos anti-parasitários e imunomodulantes da nitazoxanida (NTZ) e ivermectina (IVC), isoladas ou em associação, e do selênio (SE), associado à NTZ ou à IVC, sobre a infecção por Cryptosporidium em camundongos diabéticos. Os resultados revelaram que a terapia combinada com NTZ e IVC resultou em maior redução de oocistos fecais, enquanto a NTZ isolada mostrou a menor redução de oocistos fecais (63%). Além disso, a associação do SE com a NTZ ou IVC resultou em redução do número de oocistos fecais de 63% para 71% e de 82% para 84%, respectivamente. Todos os tratamentos, com exceção da monoterapia com NTZ, mostraram uma melhora significativa nos índices relacionados à histopatologia intestinal. Os resultados da imuno-histoquímica mostraram reversão da razão celular CD4/CD8 T normal nos camundongos infectados não tratados, no entanto, após a terapia, houve retorno à razão celular CD4/CD8 T normal. O tratamento combinado (NTZ+ IVC) demonstrou o mais alto nível de expressão celular CD4 T. Em conclusão, a terapia combinada com NTZ e IVC mostrou efeitos anti-parasitários e imunoestimuladores notáveis, especificamente para a população CD4, que parecem ser promissores para o controle da criptosporidiose em indivíduos diabéticos.

Ginsenoside Rb1 attenuates diabetic retinopathy in streptozotocin-induced diabetic rats

Purpose:To investigated the effects of ginsenoside Rb1 on diabetic retinopathy in streptozotocin-induced diabetic rats.Methods:Diabetes was induced by a single intraperitoneal injection of streptozotocin (80 mg/kg) in male Wistar rats. Ginsenoside Rb1 (20, 40 mg/kg) was injected (i.p.) once a day for 4 weeks. Then, using fundus photography, the diameter and vascular permeability of retinal vessels were investigated. Retinal histopathology was undertaken. Contents of malondialdehyde (MDA) and glutathione (GSH) in retinas were assayed. Levels of nuclear factor erythroid 2-related factor 2 (Nrf2), glutathione cysteine ligase catalytic subunit (GCLC), and glutathione cysteine ligase modulatory subunit (GCLM) were measured.Results:Treatment with ginsenoside Rb1 attenuated the diabetes-induced increase in the diameter of retinal blood vessels. Ginsenoside Rb1 reduced extravasation of Evans Blue dye from retinal blood vessels. Ginsenoside Rb1 partially inhibited the increase in MDA content and decrease in GSH level in rat retinas. Nrf2 levels in the nuclei of retinal cells and expression of GCLC and GCLM were increased significantly in rats treated with ginsenoside Rb1.Conclusion:These findings suggest that ginsenoside Rb1 can attenuate diabetic retinopathy by regulating the antioxidative function in rat retinas.(AU)

An experimental study of exenatide effects on renal injury in diabetic rats

Purpose:To investigate the effects of exenatide on renal injury in streptozotocin-induced diabetic rats.Methods:Fifty SD rats were randomly divided into normal control, model, exenatide-1, exenatide-2 and exenatide-3 groups, 10 rats in each group. The diabetic nephropathy model was constructed in later 4 groups. Then, the later 3 groups were treated with 2, 4 and 8 μg/kg exenatide for 8 weeks, respectively. The serum and urine biochemical indexes and oxidative stress and inflammatory indexes in renal tissue were determined.Results:Compared to the model group, in exenatide-3 group the serum fasting plasma glucose and hemoglobin A1c levels were significantly decreased, the fasting insulin level was significantly increased, the renal index and blood urea nitrogen, serum creatinine and 24 h urine protein levels were significantly decreased, the renal tissue superoxide dismutase and glutathione peroxidase levels were significantly increased, the malondialdehyde level was significantly decreased, and the renal tissue tumor necrosis factor alpha, interleukin 6, hypersensitive C-reactive protein and chemokine (C-C motif) ligand 5 levels were significantly decreased P<0.05).Conclusions:Exenatide can mitigate the renal injury in diabetic rats. The mechanisms may be related to its resistance of oxidative stress and inflammatory response in renal tissue.(AU)

Insulin favors acute inflammatory reaction in alloxan-diabetic tilapia during infectious aerocystitis / Insulina favorece a reação inflamatória aguda em tilápia do Nilo aloxano-diabéticas durante aerocistite infecciosa

In vertebrates, the inflammatory reaction is responsible for modulating the initial nonspecific defense until specific immunity is acquired. In this context, numerous studies in mammals have demonstrated the participation of insulin in the inflammatory response, favoring cell proliferation and the migratory capacity of endothelial cells, vascular smooth muscle cells and monocytes, as well as mediating the expression of pro-thrombotic and pro-fibrotic factors. However, little is known about the effect of this peptidic hormone on the inflammatory reaction in teleostean fish. In order to evaluate the participation of insulin in the acute inflammatory response of Nile tilapia, Oreochromis niloticus, during aerocystitis induced by Aeromonas hydrophila, and 48 aloxane-diabetic tilapia were used, constituting two groups: diabetics treated with insulin and diabetics without treatment. After six, 24, and 48 hours of inflammatory stimulation, tilapia were submitted to deep anesthesia for euthanasia and necropsy, and thus, obtaining exudate and harvesting of the swim bladder for analysis of the inflammatory reaction. Based on this premise, the present study demonstrated the participation of insulin in the acute inflammatory reaction of alloxan-diabetic tilapia by favors the cellular accumulation in the exudate, the proliferative effect of fibrous tissue and neovascularization in the inflamed site. Such findings reinforce the old hypothesis that insulin plays an important role in the innate immune response during acute inflammatory reaction, being an important pro-inflammatory hormone. However, Nile tilapia proved to be a promising experimental model for studies and advances in research involving diabetes mellitus.(AU)

Em vertebrados, a reação inflamatória é responsável por modular a defesa inicial não-específica, até que imunidade específica seja adquirida. Neste contexto, inúmeros estudos em mamíferos têm demonstrado a participação da insulina sobre a resposta inflamatória, favorecendo a proliferação celular e a capacidade migratória das células endoteliais, células do músculo liso vascular e dos monócitos, além de mediar a expressão de fatores pró-trombótico e pró-fibrótico. Porém, pouco se conhece o efeito deste hormônio peptídico sobre a reação inflamatória em peixes teleósteos. Para avaliar a participação da insulina sobre a resposta inflamatória aguda em tilápias do Nilo, Oreochromis niloticus, na aerocistite induzida por Aeromonas hydrophila, foram utilizadas 48 tilápias aloxano-diabéticas, constituindo dois grupos: dos diabéticos tratados com insulina e diabéticos sem tratamento. Após, seis, 24 e 48 horas do estimulo inflamatório, as tilápias foram submetidas à anestesia profunda para eutanásia e necropsia, e assim, obtenção de exsudato e colheita da bexiga natatória para analise da reação inflamatória. Partindo-se desta premissa, o presente estudo demonstrou a participação da insulina na reação inflamatória aguda infecciosa de tilápias do Nilo aloxano-diabéticas por favorecer o acúmulo positivo celular no exsudato, assim como o efeito proliferativo de tecido fibroso e a neovascularização no local inflamado. Tais achados reforçam a hipótese de que a insulina desempenha importante papel na resposta imune inata na reação inflamatória aguda, sendo um importante hormônio pró-inflamatório. Contudo, a tilápia do Nilo demonstrou ser um modelo experimental promissor para estudos e avanços em pesquisas envolvendo o diabetes mellitus.(AU)

Insulin favors acute inflammatory reaction in alloxan-diabetic tilapia during infectious aerocystitis / Insulina favorece a reação inflamatória aguda em tilápia do Nilo aloxano-diabéticas durante aerocistite infecciosa

In vertebrates, the inflammatory reaction is responsible for modulating the initial nonspecific defense until specific immunity is acquired. In this context, numerous studies in mammals have demonstrated the participation of insulin in the inflammatory response, favoring cell proliferation and the migratory capacity of endothelial cells, vascular smooth muscle cells and monocytes, as well as mediating the expression of pro-thrombotic and pro-fibrotic factors. However, little is known about the effect of this peptidic hormone on the inflammatory reaction in teleostean fish. In order to evaluate the participation of insulin in the acute inflammatory response of Nile tilapia, Oreochromis niloticus, during aerocystitis induced by Aeromonas hydrophila, and 48 aloxane-diabetic tilapia were used, constituting two groups: diabetics treated with insulin and diabetics without treatment. After six, 24, and 48 hours of inflammatory stimulation, tilapia were submitted to deep anesthesia for euthanasia and necropsy, and thus, obtaining exudate and harvesting of the swim bladder for analysis of the inflammatory reaction. Based on this premise, the present study demonstrated the participation of insulin in the acute inflammatory reaction of alloxan-diabetic tilapia by favors the cellular accumulation in the exudate, the proliferative effect of fibrous tissue and neovascularization in the inflamed site. Such findings reinforce the old hypothesis that insulin plays an important role in the innate immune response during acute inflammatory reaction, being an important pro-inflammatory hormone. However, Nile tilapia proved to be a promising experimental model for studies and advances in research involving diabetes mellitus.(AU)

Em vertebrados, a reação inflamatória é responsável por modular a defesa inicial não-específica, até que imunidade específica seja adquirida. Neste contexto, inúmeros estudos em mamíferos têm demonstrado a participação da insulina sobre a resposta inflamatória, favorecendo a proliferação celular e a capacidade migratória das células endoteliais, células do músculo liso vascular e dos monócitos, além de mediar a expressão de fatores pró-trombótico e pró-fibrótico. Porém, pouco se conhece o efeito deste hormônio peptídico sobre a reação inflamatória em peixes teleósteos. Para avaliar a participação da insulina sobre a resposta inflamatória aguda em tilápias do Nilo, Oreochromis niloticus, na aerocistite induzida por Aeromonas hydrophila, foram utilizadas 48 tilápias aloxano-diabéticas, constituindo dois grupos: dos diabéticos tratados com insulina e diabéticos sem tratamento. Após, seis, 24 e 48 horas do estimulo inflamatório, as tilápias foram submetidas à anestesia profunda para eutanásia e necropsia, e assim, obtenção de exsudato e colheita da bexiga natatória para analise da reação inflamatória. Partindo-se desta premissa, o presente estudo demonstrou a participação da insulina na reação inflamatória aguda infecciosa de tilápias do Nilo aloxano-diabéticas por favorecer o acúmulo positivo celular no exsudato, assim como o efeito proliferativo de tecido fibroso e a neovascularização no local inflamado. Tais achados reforçam a hipótese de que a insulina desempenha importante papel na resposta imune inata na reação inflamatória aguda, sendo um importante hormônio pró-inflamatório. Contudo, a tilápia do Nilo demonstrou ser um modelo experimental promissor para estudos e avanços em pesquisas envolvendo o diabetes mellitus.(AU)

Toll-like receptor 7 involves the injury in acute kidney ischemia/reperfusion of STZ-induced diabetic rats

PURPOSE:To determine whether Toll-like receptor 7 (TLR7) is the potential targets of prevention or progression in the renal ischemia/reperfusion (I/R) injury of STZ-induced diabetic rats.METHODS:Thirty six Sprague-Dawley rats were randomly arranged to the nondiabetic (ND) or diabetic group (DM), with each group further divided into sham (no I/R injury), I/R (ischemia-reperfusion) and CD (given by Chloroquine) group. Preoperatively, Chloroquine (40 mg/kg, intraperitoneal injection.) was administrated 6 days for treatment group. I/R animals were subjected to 25 min of bilateral renal ischemia. Renal function, histology, apoptosis, cytokines, expression of TLR7, MyD88 and NF-κB were detected.RESULTS:The serum levels of blood urea nitrogen, creatinine, IL-6 and TNF-α, apoptotic tubular epithelial cells, expression of TLR7, MyD88 and NF-κB were significantly increased in DM+I/R group, compared with ND+I/R group (p<0.05). All these changes were further improved by TLR7 inhibition Chloroquine except Paller scores (p<0.05).CONCLUSION:Toll-like receptor 7 inhibition attenuates the acute renal ischemia/reperfusion injury of STZ-induced diabetic in SD rats.(AU)

The effects of photobiomodulation therapy on Staphylococcus aureus infected surgical wounds in diabetic rats. A microbiological, histopathological, and biomechanical study

PURPOSE:To evaluate the effects of photobiomodulation therapy (PBMT) at 685 nm on diabetic wound healing in rats suffering from bacterial infection induced by Staphylococcus aureus (S. aureus).METHODS:Thirty streptozotocin-induced diabetic rats were allocated into two groups: control and PBMT. A 4-cm full-thickness linear-incision was made on the dorsal midline and was contaminated with S. aureus. The wounds in the PBMT group were irradiated daily for 5 consecutive days, starting 3 days after the induction and always in the mornings.RESULTS:The result revealed that PBMT resulted in a significant decrease in S. aureus CFU in the PBMT group in comparison to the control group (P<0.05). The length of wounds, in the 2nd and 3rd weeks, in the PBMT group were significantly shorter compared to the control group (P<0.05). PBMT caused a significant increase in the histological parameters in comparison to the control group (P<0.05). Moreover, PBMT significantly increased the breaking strength of the surgical scars produced in the skin of the PBMT group when compared to the control group (P<0.05).CONCLUSION:Photobiomodulation therapy may be useful in the management of wound infection through a significant bacterial growth inhibition and an acceleration of wound healing process.(AU)

Endoplasmic reticulum stress and renal lesion in mice with combination of high-fat diet and streptozotocin-induced diabetes

PURPOSE: To investigate in the kidney the pathologic changes and expression of GRP78 and CHOP in the Kunming (KM) mice with combination of high-fat diet and streptozotocin-induced diabetes.METHODS: Sixty two male KM mice were randomly divided into a normal control (NC) group (n=20) and a high-fat diet (HFD) group (n=42). After a four-week dietary manipulation, the KM mice in the HFD group were injected intraperitoneally with streptozotocin to induce diabetes. After diabetic models were successfully established, the kidneys were excised and conserved for further test.RESULTS: No significant difference in the body weight was observed after the dietary manipulation (p=0.554). After the streptozotocin was injected, fasting blood glucose levels in the diabetes group (DM) were significantly higher than that in the NC group (p＜0.0001). Glomerular atrophy observed under light microscope in the DM group was more serious compared with the NC group. The expression of GRP78 and CHOP in the kidneys of the mice in the DM group were higher compared with the NC group.CONCLUSION: Renal lesion occurs in the diabetic Kunming mice induced by combination of high-fat diet and low-dose streptozotocin, and endoplasmic reticulum stress and CHOP may contribute to the injury process.(AU)

EFEITO PROTETOR DE AGENTES ANTIOXIDANTES SOBRE O SISTEMA CARDIOVASCULAR DE RATOS DIABÉTICOS: ANÁLISE HEMATOLÓGICA, BIOQUÍMICA E HISTOMORFOMÉTRICA

Introdução: complicações cardiovasculares decorrentes da diabetes mellitus são frequentes, sendo as mais comuns a cardiomiopatia isquêmica e a disfunção do ventrículo esquerdo. Essas complicações estão associadas ao estresse oxidativo e à formação de espécies reativas ao oxigênio, resultantes da condição hiperglicemiante. O ácido alfa lipóico e o extrato de guaraná são alimentos funcionais com uma promissora ação antioxidante. A hipótese científica deste trabalho é que a suplementação com esses dois agentes antioxidantes na dieta de pacientes diabéticos atenue os agravos ao sistema cardiovascular. Objetivo: avaliar os efeitos das dietas experimentais à base de ácido alfa lipóico ou guaraná sobre o sistema cardiovascular de ratos Wistar com diabetes mellitus induzida por aloxana, avaliando a viabilidade do seu uso como terapia auxiliar no tratamento da diabetes. Metodologia: foram utilizados 42 ratos Wistar aleatoriamente divididos em 6 grupos: Grupo Controle (GC); Grupo Diabético Controle (GDC); Grupo Alfa Lipóico (GCAL) e Grupo Diabético Alfa Lipóico (GDAL); Grupo Guaraná (GCG) e Grupo Diabético Guaraná (GDG). O processo de indução ao diabetes contou com um jejum de 30 horas e após esse período os animais receberam uma injeção de Aloxana monohidratada a 1,5% numa dosagem de 150 mg/kg. Após 8 semanas, os ratos foram anestesiados, amostras de sangue foram coletadas para posterior análise bioquímica e hematológica. Em seguida, os animais sofreram eutanásia para a coleta do coração e aorta com posterior processamento para parafina, análise morfométrica e estereológica. Resultados: todos os animais que sofreram indução apresentaram glicemia acima de 270 mg/dl e redução na massa corporal durante todo o período experimental. O consumo de ração foi maior nos grupos diabéticos com exceção do GDAL. O grupo GDG apresentou a pressão arterial sistólica sem diferir do GC ao final do experimento. Houve redução nos níveis séricos de triglicerídeos e VLDL nos grupos suplementados com ácido Alfa Lipóico. A creatinina sérica apresentou um aumento no GDC, porém os grupos GDG e GDAL mantiveram os níveis próximos aos do GC. As concentrações de ALT e AST mostraram um aumento significativo no GDC quando comparado ao GC. Os grupos GDG e GDAL mantiveram seus níveis próximo aos do GC. Foi observado uma diminuição na espessura da parede da aorta no GDC, GDG e GDAL quando comparados com seus respectivos controles e a área da parede foi menor em GDG e GDAL, quando comparados com os demais grupos. A espessura de um dos ramos da artéria coronária esquerda apresentou um aumento nos grupos GDC e GCAL quando comparados aos demais grupos, e houve uma redução no GDAL quando comparado ao controle, assim como um aumento na área luminal desta artéria no GDAL. A maior densidade volumétrica de colágeno (Vv) foi observado nos grupos GDC e GDAL quando comparados com os demais grupos. Os grupos GDC, GCAL e GDAL apresentaram fibrilas de colágeno mais finas com birrefringência verde, já os grupos GC e GDG apresentaram fibrilas de colágeno mais espessas com birrefringência alaranjada. Conclusão: O consumo de guaraná e do ácido alfa lipóico pelos modelos animais apresentados atuou de forma benéfica sobre os parâmetros de importância para a avaliação da função cardiovascular, mantendo diversos destes ao nível basal e contribuindo para a manutenção da integridade tecidual do coração, aorta e artéria coronária, apesar do dano causado pela diabetes mellitus.

Introduction: cardiovascular complications resulting from diabetes mellitus are frequent, and the most common are ischemic cardiomyopathy and left ventricular dysfunction. These complications are associated with oxidative stress and the generation of reactive oxygen species, resulting from the hyperglycemic condition. Alpha-lipoic acid and guarana extract are functional foods with a promising antioxidant action. The scientific hypothesis of this study is that supplementation with these two antioxidants in the diet of diabetic patients reduces the damage to the cardiovascular system. Objective: to evaluate the effects of experimental diets based on alpha-lipoic acid or guarana on the cardiovascular system of Wistar rats with alloxan-induced diabetes mellitus, evaluating the viability of its use as an auxiliary therapy in the treatment of diabetes. Methods: 42 Wistar rats were randomly divided into 6 groups: Control Group (CG); Diabetic Control Group (DCG); Alpha Lipoic Group (LCG) and Diabetic Alpha Lipoic Group (LDG); Guarana Group (GCG) and Guarana Diabetic Group (GDG). To the diabetes induction process, a 30-hour fast was applied and then the animals received an injection of 1.5% Alloxan monohydrate in a dosage of 150 mg/kg. After 8 weeks, the rats were anesthetized, and blood samples were collected for further biochemical and hematological analysis. Then, the animals were euthanized to collect the heart and aorta with further processing into paraffin, morphometric and stereological analysis. Results: all animals that underwent induction showed blood glucose above 270 mg/dL and a reduction in body mass throughout the experimental period. Feed intake was higher in diabetic groups except for LDG. The GDG presented systolic blood pressure without differing from the CG at the end of the experiment. There was a reduction in serum levels of triglycerides and VLDL in groups supplemented with alpha-lipoic acid. Serum creatinine increased in DCG, however, the GDG and LDG groups maintained levels close to CG. ALT and AST concentrations showed a significant increase in DCG when compared to CG. The GDG and LDG groups maintained their levels close to those of the CG. A decrease in the thickness of the aorta wall was observed in DCG, GDG, and LDG when compared with their respective control groups and the area of the artery wall was smaller in GDG and LDG, when compared with the other groups. The thickness of one of the branches of the left coronary artery showed an increase in the DCG and LCG groups when compared to the other groups, and there was a reduction in the LDG when compared to CG, as well as an increase in the luminal area of this artery in the LDG. The highest volumetric density of collagen (Vv) was observed in the DCG and LDG groups when compared with the other groups. The groups DCG, LCG, and LDG had thinner collagen fibrils with green birefringence, whereas the groups CG and GDG had thicker collagen fibrils with orange birefringence. Conclusion: The consumption of guarana and alpha-lipoic acid by the animal models, presented in this study, acted beneficially on the parameters of importance for the evaluation of cardiovascular function, maintaining several of them at the basal level and contributing to the maintenance of the tissue integrity of the heart, aorta and coronary artery, despite the damage caused by diabetes mellitus.

Improvement of bone repair in diabetic rats subjected to 780 nm low-level laser therapy

To investigate the effect of low-level laser therapy on bone healing in diabetic rats. METHODS: Bone cavities (19 mm diameter) were performed in the femur of 72 alloxan-induced diabetic rats, which were assigned into four groups: CTR (non-diabetic control), DBT (diabetic) CTRL (non-diabetic irradiated) and DBTL (diabetic irradiated). Low-level laser therapy was performed every 48h for seven days. Animals were euthanized at seven, 18 and 30 days. Alkaline phosphatase serum levels and bone repair were analyzed. RESULTS: Low-level laser therapy significantly increased alkaline phosphatase in at seven and 18 days (p 0.001), and improved bone healing at seven (p 0.01), 18 (p 0.05) and 30 (p 0.01) in diabetic animals. In addition, bone healing in irradiated diabetic group was statistically similar to control group at 30 days (p>0.05). CONCLUSION: Low-level laser therapy increased the serum levels of alkaline phosphatase and improved bone healing in alloxan-induced diabetic rats.(AU)

Antidiabetic effect of Gymnema sylvestre in Streptozotocin induced diabetes in rats

The purpose of the study was to study the hypoglycemic effect of Gymnema sylvestre in streptozotocin induced diabetic rat model. G. sylvestre was administered at the dose rate of 50 and 100 mg/kg b w and was compared with standard hypoglycemic drug, glibenclamide for its anti hyperglycemic effect. There was improvement in various parameters such as body weight, haemoglobin, serum glucose, cholesterol, triglycerides, AST, ALT and antioxidant enzymes in all the treatment groups. G. sylvestre elicited dose dependent effect with 100 mg/kg b w being more effective in alleviating most of the diabetic clinical signs. The findings were clearly substantiated by histopathology and immunohistochemistry. In conclusion, G. sylvestre has significant antidiabetic effect at 100 mg/kg b w when administered daily for 45 days.

Antidiabetic effect of Gymnema sylvestre in Streptozotocin induced diabetes in rats

The purpose of the study was to study the hypoglycemic effect of Gymnema sylvestre in streptozotocin induced diabetic rat model. G. sylvestre was administered at the dose rate of 50 and 100 mg/kg b w and was compared with standard hypoglycemic drug, glibenclamide for its anti hyperglycemic effect. There was improvement in various parameters such as body weight, haemoglobin, serum glucose, cholesterol, triglycerides, AST, ALT and antioxidant enzymes in all the treatment groups. G. sylvestre elicited dose dependent effect with 100 mg/kg b w being more effective in alleviating most of the diabetic clinical signs. The findings were clearly substantiated by histopathology and immunohistochemistry. In conclusion, G. sylvestre has significant antidiabetic effect at 100 mg/kg b w when administered daily for 45 days.(AU)

Botulinum toxin type A on cutaneous flap viability in diabetic and tobacco-exposed rats

To investigate the effect of Botulinum toxin A (BoNTA) on skin flap viability in healthy, tobacco-exposed and diabetic rats. Ninety male Wistar rats (250-300g) were randomly divided into six groups: control+saline (C1), control+BoNTA (C2), tobacco-exposed+saline (T1), tobacco-exposed+BoNTA (T2) diabetes+saline (D1) and diabetes+BoNTA (D2). A dorsal cutaneous flap (3×10cm) was performed. Survival area and total area of the flaps were measured. Lumen diameter, external arterial diameter and lumen/wall thickness ratio were recorded. Survival area increased in control group with BoNTA injection compared with control animals injected with saline (C2 x C1; 0.9±0.1 vs0.67±0.15, p= 0.001). A similar result was found in diabetes group injected with BontA (D2 x D1; 0.97±0.2 vs0.61±0.24, p=0.018). No difference was observed in skin flap viability in tobacco-exposed groups (T2 x T1; 0.74±0.24 vs 0.64±0.21, p=0.871). Lumen diameter (p= 0.004), external arterial diameter (p = 0.0046,) and lumen/wall thickness ratio (p= 0.003) were increased in diabetes+BoNTA-treated animals. This effect was not observed in control or in tobacco-exposed groups. Botulinum toxin A increased skin flap viability in control and diabetic rats on the seventh post-operative day. Increased lumen diameter, external arterial diameter, and lumen/wall thickness ratio were observed in the diabetes+BoNTA group. BoNTA had no effect in the tobacco-exposed group on the seventh postoperative day.(AU)