Gum arabic and red propolis protecteting colorectal preneoplastic lesions in a rat model of azoxymethane

Abstract Purpose: To evaluate red propolis, gum arabic and L-lysine activity on colorectal preneoplastic lesions induced by azoxymethane (AOM). Methods: The study featured 4 control groups (I-IV) and 4 experimental groups (V-VIII), totaling 48 rats. Once a week for 2 weeks, animals on control groups received saline, while animals in experimental groups received azoxymethane (15 mg/kg i.p.). The follow up along 16 weeks included daily oral gavage to administer water (I and V), L-lysine (150 mg/kg)(II and VI), própolis (100mg/5ml/kg)(III and VII), or gum arabic (5ml/kg)(IV and VIII). Was performed surgery on the animals in the end of this time in order to collect blood for biological assays (TBARS, GSH), followed by their sacrifice to tissue extract. Results: Oxidative stress (TBARS) and the number of aberrant crypt foci (ACF) in distal colon were lower using própolis (p<0.01 for both parameters). Gum arabic reduced preneoplastic lesions (ACF ≤ 4 crypts) on distal colon and on the entire colon (p<0.05). Conclusions: Red propolis reduced AOM-induced oxidative stress (TBARS) and total number of ACF in the distal colon. L-lysine neither protected against nor enhanced AOM-induced ACF. Gum arabic reduced the number of ACF.

Effect of red propolis on hamster cheek pouch angiogenesis in a new sponge implant model

Abstract Purpose: To evaluate the effects of red propolis on cheek pouch angiogenesis in a hamster new model sponge implant. Methods: Forty eight animals divided into eight groups. (Groups I-IV), the animals were treated for 15 days before and 10 days after sponge implantation. (Groups V-VIII), the animals were treated for 10 days after sponge implantation (GI and GV: red propolis 100 mg/kg, GII and GVI: celecoxib 20 mg/kg, GIII and GVII: 1% gum arabic 5 mL/kg, GIV and GVIII: distilled water 5 mL/kg). On the 11th day of implantation, the animals were anesthetized for stereoscopic microscopic imaging and morphometric quantification of angiogenesis (SQAN), followed by histopathological evaluation (H&E). Results: In the SQAN analysis, no significant difference was found between the groups. However, on histology, propolis was found reduce the population of mastocytes in the qualitative analyses (p = 0,013) in the quantitative analyses to reduce the number of blood vessels (p = 0,007), and increase the macrophage count (p = 0,001). Conclusion: Red propolis inhibited inflammatory angiogenesis when administered before andcontinuously after sponge implant, and was shown to have immunomodulating effects on inflammatory cells (mastocytes and macrophages) in a new sponge implant hamster model.

Transitional metaplasia in intestinal epithelium of rats submitted to intestinal cystoplasty and treatment with L -lysine

Abstract Purpose: To evaluated the effects of L-lysine on the intestinal and urothelial epithelia in cystoplasty in rats. Methods: Twenty-eight 9-week-old rats were assigned to 4 groups: Group A (n=8) cystoplasty followed by administration of L-lysine (150 mg/kg body weight by gavage) for 30 weeks; Group B (n=8) cystoplasty + water for 30 weeks; Group C (n=6) L-lysine for 30 weeks; Group D (n=6) water for 30 weeks. Results: On histopathology with hematoxylin and eosin, mild to moderate hyperplasia transitional was observed in at the site of anastomosis in all animals submitted to cystoplasty (Groups A and B), but "transitional metaplasia" of the intestinal glandular epithelium was more accentuated in Group A (p=0.045). No inflammatory cells, dysplasia or abnormalities were observed. Staining with Alcian blue revealed a substantial reduction of goblet cells and mucins in the colon segment (Groups A and B). Conclusion: The administration of L-lysine to rats accelerated the development of transitional metaplasia in the epithelium of the colon segment in cystoplasty.

Carcinogenesis in rats subjected to a new model ureterosigmoidostomy and treated with L-lysine

ABSTRACT PURPOSE: To evaluate the effects of L-lysine on the intestinal and urothelial epithelium of rats subjected to ureterosigmoidostomy (new model for surgical carcinogenesis). METHODS: Forty-two rats, 9 weeks of age, were divided into 6 groups. Animals in groups A, B, C were subjected to ureterosigmoidostomy (US) and treated with L-lysine, celecoxib and H2O, respectively. Groups D, E and F (non-operated controls) received L-lysine, celecoxib and H2O, respectively. The L-lysine dose was 150 mg/kg and that of celecoxib was 20 mg/kg. The colon was analyzed for the presence of aberrant crypt foci (ACF) under a stereomicroscope.The tissue was stained with hematoxylin and eosin and PAS alcian blue. RESULTS: There were rare ACF, and there was no statistically significant difference between the groups. Histopathologic study of the ureteral epithelium identified moderate to severe urothelial hyperplasia in rats with ureterosigmoidostomy. Transitional hyperplasia in the ureters of animals receiving L-lysine (A) showed an apparent difference compared to the control (C) (P=0.2424). There was no dysplasia or atypia CONCLUSION: L-lysine does not promote carcinogenesis of the intestinal and urethelial epithelium of rats subjected to ureterosigmoidostomy at the doses and times studied.

Bladder carcinogenesis in rats subjected to ureterosigmoidostomy and treated with L-lysine / Carcinogênese de bexiga em ratas submetidas à ureterossigmoidostomia tratadas com L-lisina

ABSTRACT Objective: to evaluate the effect of L-lysine in the bladder and intestinal epithelia in rats submitted to vesicosigmoidostomy. Methods: we divided forty Wistar rats into four groups: group I - control group (Sham); group II - submitted to vesicosigmoidostomy and treated with L-lysine 150mg/kg; group III - submitted only to vesicosigmoidostomy; and group IV - received L-lysine 150mg/kg. After eight weeks the animals were sacrificed. Results: in the bladders of all operated animals we observed simple, papillary and nodular hyperplasia of transitional cells, transitional cell papillomas and squamous metaplasia. As for the occurrence of aberrant crypt foci in the colons of operated animals, we did not observe statistically significant differences in any of the distal, proximal and medium fragments, or in all fragments together (p=1.0000). Conclusion: Although statistically there was no promotion of carcinogenesis in the epithelia of rats treated with L-lysine in the observed time, it was clear the histogenesis of bladder carcinogenesis in its initial phase in all operated rats, this being probably associated with chronic infection and tiny bladder stones.

RESUMO Objetivo: o objetivo deste trabalho é avaliar o efeito da L-lisina nos epitélios vesical e intestinal de ratas submetidas à vesicossigmoidostomia. Métodos: quarenta ratas Wistar, foram divididas em quatro grupos: grupo I- grupo controle (Sham); grupo II- submetido à vesicossigmoidostomia e tratado com L-lisina 150mg/kg; grupo III- submetido apenas à vesicossigmoidostomia; e grupo IV- recebeu L-lisina 150mg/kg. Após oito semanas os animais foram sacrificados. Resultados: na bexiga de todos os animais operados observou-se hiperplasia simples, papilar e nodular de células transicionais, papiloma de células transicionais e metaplasia escamosa. Quanto à ocorrência de focos de criptas aberrantes nos colos dos animais operados, não foi evidenciado diferença estatística significante em nenhum dos fragmentos distal, proximal e médio, e todos juntos (P=1,0000). Conclusão: apesar de, estatisticamente, não ter havido promoção de carcinogênese nos epitélios dos ratos tratados com L-lisina, no tempo observado, é nítida a histogênese da carcinogênese de bexiga em sua fase inicial, no epitélio vesical, em todos os ratos operados, estando esta provavelmente associada à infecção crônica e aos diminutos cálculos vesicais.

Oil mixes omega 9, 6 and 3, enriched with seaweed, promoted reduction of thermal burned modulating NF-kB and Ki-67

PURPOSE: To examine the effects of the oil mixes (ω-9, ω-6 and ω-3) in rats subjected to thermal burn. It was also aimed to assess whether the sources of ω3 would interfere with the effect of such mixes on the thermal injury. METHODS: Thirty-six rats distributed into five groups: burned + water, burned + isolipid mix, burned + oil mix 1 (ALA), burned + oil mix 2 (ALA + EPA + DHA of fish) and burned + oil mix 3 (ALA + DHA from seaweed). The thermal injury was involving total thickness of skin. After the burns animals received the oil mixes for seven days. The lesions were evaluated by immunohistochemistry. RESULTS: Animals receiving mix 3 showed a smaller extension of the thermal injury as compared to those that were supplemented with other oils mixes. Expression of Ki-67 in the receiving Mix 3 increased as compared to all the other groups. Animals supplemented with mix 3 were able to inhibit NF-κB in injured tissue. CONCLUSION: Rats received oil mix in which the source of ω3 (ALA+DHA of seaweed) showed inhibition of NF-κB, increase in cell proliferation, and reduction the extension of thermal lesion. .

Potential chemoprotective effects of green propolis, L-lysine and celecoxib on bone marrow cells and peripheral blood lymphocytes of Wistar rats subjected to bladder chemical carcinogenesis

PURPOSE: To evaluate the genotoxicity of propolis and L-lysine, as well as their effects on the possible cellular damage in erythroblasts (bone marrow) and leukocytes (peripheral blood) caused by the carcinogen BBN (n - butyl - n {4 - hydroxybutyl} nitrosamine) in rats subjected to bladder carcinogenesis and treated with green propolis and L-lysine. METHODS: One hundred and twenty five rats were distributed into the following groups: I, IIA, IIB, III, K, L M N, X, XI, XII and XIII. Groups I to X received BBN in drinking water for 14 weeks (wks). Group I was treated with intragastric (ig) propolis at 150 mg/kg body weight, for 44 wks, beginning 30 days before start of BBN. Groups IIA and III were treated with propolis (150 mg/kg), for 40 wks, subcutaneous (sc) and ig, respectively, beginning simultaneously with BBN. On the 32nd wk, the animals of groups L, M and N were treated ig with L-lysine (300 mg/kg), celecoxib (30 mg/kg) and propolis (300 mg/kg), respectively, up to the 40th wk. The groups that received only BBN (IIB and K) were treated with water, sc and orally, respectively, for 40 wks. Groups XI, XII and XIII received respectively propolis (150 mg/kg), L-lysine (150 mg/kg) and water ig for 40 wks. After 40 wks, the surviving animals were anesthetized and subjected to femoral bone marrow aspiration and blood collection from the aorta, for CA and MNT, respectively, for investigation of genotoxicity. RESULTS: Groups IIB and K, which received only BBN and water, showed the greatest DNA damage in peripheral leukocytes (CA) and largest number of micronuclei in bone marrow erythrocytes (MNT) in relation to all other groups that received BBN and lysine and/or propolis (p<0.001). CONCLUSIONS: Both propolis and L-lysine are effective in protecting against genotoxicity, as well not being genotoxic themselves toward the cells evaluated, at the doses and times administered and according to the two tests utilized. .

Repercussão hepática da carcinogênese colorretal induzida pelo azoximetano / Hepatic repercussions of azoxymethane-induced colorectal carcinogenesis

OBJETIVO: Avaliar as repercussões hepáticas da carcinogênese colônica induzida por diferentes doses e tempos de exposição ao azoximetano em ratos Wistar. MÉTODOS: Quarenta e quatro ratos foram distribuídos em quatro grupos. Os animais tinham oito semanas no início do experimento. No grupo 1, receberam 1.0mL de solução salina intraperitonealmente uma vez por semana por duas semanas. No grupo 2, receberam 15 mg/kg de azoximetano intraperitonealmente uma vez por semana por duas semanas. Esses animais foram mortos na 15ª semana do experimento. Os animais do grupo 3 receberam solução salina intraperitonealmente uma vez por semana por duas semanas. Os animais do grupo 4 receberam 20mg/kg de azoximetano intraperitonealmente uma vez por semana por duas semanas. Esses animais foram mortos na 26ª semana do experimento. Os fragmentos de tecido hepático foram corados pela hematoxilina e eosina e avaliadas microscopicamente. RESULTADOS: Grupo 1 e grupo 2 diferiram significantemente em relação a esteatose, mas não houve diferença entre o grupo 3 e o grupo 4. No entanto, no grupo 4 foram observadas lesões pré-neoplásicas (focos de células alteradas, claras, vacuoladas, basofílicas, anfofílicas, tigróides, oncocíticas, pequenas ou acidófilas, espongioses e pelioses) e lesões neoplásicas (colangiomas e adenomas) contendo hepatócitos atípicos de permeio, não identificados no grupo 3. CONCLUSÃO: No modelo de carcinogênese colorretal, lesões hepáticas pré-neoplásicas e neoplásicas aparecem e evoluem na proporção do tempo e dose de exposição ao azoximetano.

OBJECTIVE: To evaluate the hepatic effects of colonic carcinogenesis induced by azoxymethane at different doses and times of exposure in rats. METHODS: Forty-four Wistar rats were divided into four groups. The animals were eight weeks at the beginning of the experiment. group 1 received 1.0ml of saline intraperitoneally once a week for two weeks. Group 2 received 15 mg/kg of azoxymethane intraperitoneally once a week for two weeks. These animals were killed at the 15th week of the experiment. The animals of group 3 received saline intraperitoneally once a week for two weeks. Group 4 animals received 20mg/kg of azoxymethane intraperitoneally once a week for two weeks. These animals were killed at the 26th week of the experiment. The fragments of liver tissue were stained with hematoxylin and eosin and evaluated microscopically. RESULTS: Groups 1 and 2 differed significantly in relation to steatosis, no difference having been found between group 3 and group 4. However, in group 4 we observed pre-neoplastic lesions (foci of altered, clear, vacuolated, basophilic, amphophilic tigroid, oncocytic, small or acidophilus cells, spongiosis and peliosis) and neoplastic lesions (adenomas and colangiomas) containing atypical hepatocytes in between, not identified in group 3. CONCLUSION: In the model of colorectal carcinogenesis, preneoplastic and neoplastic hepatic lesions appear and evolve in proportion to the time of exposure and dose of azoxymethane.

Experimental model of ultrasound thermotherapy in rats inoculated with Walker-236 tumor / Modelo experimental de termoterapia ultrassônica em ratos inoculados com tumor de Walker-236

PURPOSE: To develop a model to evaluate the effects of focal pulsed ultrasound (US) waves as a source of heat for treatment of murine subcutaneous implanted Walker tumor. METHODS: An experimental, controlled, comparative study was conducted. Twenty male Wistar rats (160-300 g) randomized in 2 equal groups (G-1: Control and G-2: Hyperthermia) were inoculated with Walker-256 carcinosarcoma tumor. After 5 days G-2 rats were submitted to 45ºC hyperthermia. Heat was delivered directly to the tumor by an ultrasound (US) equipment (3 MHz frequency, 1,5W/cm³). Tumor temperature reached 45º C in 3 minutes and was maintained at this level for 5 minutes. Tumor volume was measured on days 5, 8, 11, 14 e 17 post inoculation in both groups. Unpaired t-test was used for comparison. P<0.05 was considered significant. RESULTS: Tumor volume was significantly greater in day 5 and decreased in days 11, 14 and 17 in treated rats. Rats treated with hyperthermia survived longer than control animals. On the 29th day following tumor inoculation, 40 percent of control rats and 77.78 percent of hyperthermia-treated rats remained alive. CONCLUSION: The proposed model is quite simple and may be used in less sophisticated laboratory settings for studying the effects of focal hyperthermia in the treatment of malignant implanted tumours or in survival studies.

OBJETIVO: Desenvolver um modelo para avaliar os efeitos do ultra-som focal pulsado como fonte de calor para o tratamento de tumores de Walker subcutâneos implantados em ratos. MÉTODOS: Um estudo experimental, controlado, comparativo foi realizado. Vinte ratos Wistar machos (160-300 g) divididos em dois grupos (G-1: Controle e G-2: hipertermia) foram inoculados com tumor de Walker carcinossarcoma-256. Após cinco dias os ratos do grupo G-2 ratos foram submetidos a hipertermia (45ºC). O calor foi aplicado diretamente no tumor por um equipamento de ultrassonografia (3 MHz, 1,5 W/cm³). A temperatura no tumor atingiu 45ºC em 3 minutos e foi mantida nesse nível por 5 minutos. O volume do tumor foi medido nos dias 5, 8, 11, 14 e 17 após a inoculação, em ambos os grupos. Teste t não pareado foi utilizado para comparação. P <0,05 foi considerado significante. RESULTADOS: O volume do tumor foi significativamente maior no 5º dia e diminuiu nos dias 11, 14 e 17 nos ratos tratados. Animais submetidos à hipertermia sobreviveram mais tempo que os animais do grupo controle. No 29º dia após a inoculação do tumor, 40 por cento dos ratos do grupo controle e 77,78 por cento dos ratos tratados com hipertermia permaneceram vivos. CONCLUSÃO: Os resultados obtidos mostram que o modelo proposto é bastante simples e pode ser utilizado em laboratórios menos sofisticados para estudar os efeitos da hipertermia focal no tratamento dos tumores malignos implantados ou em estudos de sobrevida.

L-alanyl-glutamine pretreatment attenuates acute inflammatory response in children submitted to palatoplasty / Pré-tratamento com L-alanil-glutamina atenua a resposta inflamatória aguda em crianças submetidas à palatoplastia

PURPOSE: To evaluate the effects of L-alanyl-glutamine (L-Ala-Gln) pretreatment on oxidative stress, glycemic control and inflammatory response in children submitted to palatoplasty. METHODS: Thirty male children scheduled for routine palatoplasty, age range 2-10 years, were randomly assigned to 2 groups (n=15): Group A (saline, control) and Group B (L-Ala-Gln). Group A received normal saline 100 ml, delivered intravenously by infusion pump over 3 hours preceding surgical procedure. Group B was treated with L-Ala-Gln, 20 percent solution (0.5g/Kg), adding saline to complete 100ml. Peripheral venous blood samples were collected at 5 different time-points: T1- at the beginning of the study, 3 h prior to the surgical procedure; T2- at the end of the infusion (before the surgical procedure), T3- at the end of the surgical procedure, T4- 6 h postoperative and T5- 12 h postoperative. Parameters analyzed included glutathione (GSH), thiobarbituric acid reactive substances (TBARS), glucose, insulin, C-reactive protein (CRP) and interleukin-6 (IL-6). RESULTS: No statistically significant differences were found between groups comparing glucose, insulin, TBARS, GSH and IL-6 levels. However, glucose levels increased (P <0.001) in T4 and T5 as compared to baseline (T1) in control group as opposed to L-Ala-Gln group. IL-6 increased in both groups during the postoperative period, indicating an increased inflammatory response. L-Ala-Gln pretreatment did not suppress the increase of IL-6, but reduced the increase of postoperative CRP levels (T5, p <0.01). CONCLUSION: Pretreatment with L-Ala-Gln in children submitted to palatoplasty attenuates the inflammatory response in early post-operative period and promoted a better glycemic control.

OBJETIVO: Avaliar os efeitos do pré-tratamento com L-alanil-glutamina (L-Ala-Gln) sobre o estresse oxidativo, o controle glicêmico e a resposta inflamatória em crianças submetidas à palatoplastia. MÉTODOS: Trinta crianças do sexo masculino, agendadas para palatoplastia, faixa etária 2-10 anos, foram distribuídas aleatoriamente em dois grupos (n = 15): Grupo A (salina, controle) e Grupo B (L-Ala-Gln). O grupo A recebeu solução salina 0,9 por cento 100 ml, administrado por via intravenosa utilizando uma bomba de infusão durante 3 horas anteriores ao procedimento cirúrgico. O grupo B foi tratado com L-Ala-Gln, solução a 20 por cento (0,5 g/kg), acrescentando soro fisiológico até completar 100 ml. Amostras de sangue venoso periférico foram coletadas em cinco momentos diferentes: T1 (3 h antes do procedimento cirúrgico); T2 (no final da perfusão), T3 (no final do procedimento cirúrgico), no pós-operatório, após 6 h (T-4) e 12 h (T5). Os parâmetros analisados foram a glutationa (GSH), ácido tiobarbitúrico (TBARS), glicose, insulina, proteína C-reativa (PCR) e interleucina-6 (IL-6). RESULTADOS: Não houve diferença significante entre os grupos comparando as concentrações de glicose, insulina, TBARS, GSH e IL-6. No entanto, os níveis de glicose aumentaram em T4 e T5, comparado ao basal (T1) (P <0,001) e a IL-6 aumentou em ambos os grupos durante o período pós-operatório, sinalizando o aumento da resposta inflamatória. O pré-tratamento com L-Ala-Gln não suprimiu o aumento de IL-6, mas reduziu o aumento pós-operatório de PCR (T5, p<0,01). CONCLUSÃO: O pré-tratamento com L-Ala-Gln em crianças submetidas à palatoplastia atenua a resposta inflamatória no período pós-operatório imediato, promovendo um melhor controle glicêmico.