Persistent Inflammatory Activity in Blood Cells and Artery Tissue from Patients with Previous Bare Metal Stent

BACKGROUND: Studies have pointed out a higher mortality after coronary artery bypass surgery (CABG) in patients with stent. OBJECTIVE: To evaluate inflammatory markers in peripheral blood cells and in coronary artery tissue samples obtained during CABG in patients with stent compared to controls. METHODS: The case series consisted of two groups, one with previous stent implantation (n = 41) and one control (n = 26). The expression of the LIGHT, IL-6, ICAM, VCAM, CD40, NFKB, TNF, IFNG genes was analyzed in peripheral blood cells collected preoperatively. The coronary artery was evaluated for: interleukin-6, ICAM, VCAM, CD40, NFKB, TNF-alpha and IFN-gamma by immunohistochemistry. A total of 176 tissue samples were grouped for analysis in: A1- arteries with stent (n = 38); A2- native arteries from patients with stent in another artery (n = 68); and A3- arteries without stent from controls undergoing routinely CABG surgery (n = 70). A significance level of 0.05 was adopted. RESULTS: Patients with stent showed higher TNF (p = 0.03) and lower CD40 gene expression (p = 0.01) in peripheral blood cells than controls without stent. In coronary artery samples, the TNF-alpha protein staining was higher in the group A1, not only in the intima-media layer (5.16 ± 5.05 vs 1.90 ± 2.27; p = 0.02), but also in the adipose tissue (6.69 ± 3.87 vs 2.27 ± 4.00; p < 0.001). Furthermore, group A1 had a higher interleukin-6 protein staining in adipose tissue than group A3 (p = 0.04). CONCLUSION: We observed a persistently higher systemic TNF expression associated with exacerbated TNF-alpha and interleukin-6 local production in patients with stents. This finding may contribute to a worse clinical outcome.

Persistent Inflammatory Activity in Blood Cells and Artery Tissue from Patients with Previous Bare Metal Stent.

BACKGROUND: Studies have pointed out a higher mortality after coronary artery bypass surgery (CABG) in patients with stent. OBJECTIVE: To evaluate inflammatory markers in peripheral blood cells and in coronary artery tissue samples obtained during CABG in patients with stent compared to controls. METHODS: The case series consisted of two groups, one with previous stent implantation (n = 41) and one control (n = 26). The expression of the LIGHT, IL-6, ICAM, VCAM, CD40, NFKB, TNF, IFNG genes was analyzed in peripheral blood cells collected preoperatively. The coronary artery was evaluated for: interleukin-6, ICAM, VCAM, CD40, NFKB, TNF-alpha and IFN-gamma by immunohistochemistry. A total of 176 tissue samples were grouped for analysis in: A1- arteries with stent (n = 38); A2- native arteries from patients with stent in another artery (n = 68); and A3- arteries without stent from controls undergoing routinely CABG surgery (n = 70). A significance level of 0.05 was adopted. RESULTS: Patients with stent showed higher TNF (p = 0.03) and lower CD40 gene expression (p = 0.01) in peripheral blood cells than controls without stent. In coronary artery samples, the TNF-alpha protein staining was higher in the group A1, not only in the intima-media layer (5.16 ± 5.05 vs 1.90 ± 2.27; p = 0.02), but also in the adipose tissue (6.69 ± 3.87 vs 2.27 ± 4.00; p < 0.001). Furthermore, group A1 had a higher interleukin-6 protein staining in adipose tissue than group A3 (p = 0.04). CONCLUSION: We observed a persistently higher systemic TNF expression associated with exacerbated TNF-alpha and interleukin-6 local production in patients with stents. This finding may contribute to a worse clinical outcome.

Oxidative DNA damage in diabetic and mild gestational hyperglycemic pregnant women.

BACKGROUND: Pregnant women with mild gestational hyperglycemia present high risk for hypertension, obesity and hyperglycemia, and appeared to reproduce the model of metabolic syndrome in pregnancy, with hyperinsulinemia and insulin resistance. Our clinical studies showed that mild gestational hyperglycemia or gestational diabetes are related to similar adverse maternal and perinatal outcomes. Hyperglycemia and other factors associated with diabetes generate reactive oxygen species that increase DNA damage levels. The aim of this study was to evaluate oxidative DNA damage in lymphocytes of pregnant women with diabetes or mild gestational hyperglycemia. METHODS: The study included 111 pregnant women distributed into three groups based on oral glucose tolerance test (OGTT) and glycemic profiles (GP), as follows: Normal OGTT and GP (control group); Normal OGTT and abnormal GP (mild gestational hyperglycemia group); Abnormal OGTT and GP (diabetic group). Maternal blood samples (5-10 mL) were collected and processed for determination of oxidative DNA damage by the comet assay, using Fpg and Endo III enzymes. Urine samples were also collected for determination of 8-OHdG concentrations by ELISA. RESULTS: Subjects in the diabetes group presented increased amount of oxidized purines, while mild gestational hyperglycemia women presented with increased oxidized pyrimidines, compared to the control group. CONCLUSION: Gestational, overt diabetes and mild gestational hyperglycemia, were all related to increased oxidative DNA damage. Diabetic pregnant women showed increased level of oxidative DNA damage, perhaps mainly due to hyperglycemia. On the other hand, oxidative DNA damage detected in women with mild gestational hyperglycemia might be associated with repercussions from obesity, hypertension and/or insulin resistance. Interestingly, the type of DNA base affected seemed to be dependent on the glycemic profile or oxidative stress.

Oxidative DNA damage in diabetic and mildgestational hyperglycemic pregnant women

Pregnant women with mild gestational hyperglycemia present high risk for hypertension, obesity andhyperglycemia, and appeared to reproduce the model of metabolic syndrome in pregnancy, with hyperinsulinemiaand insulin resistance. Our clinical studies showed that mild gestational hyperglycemia or gestational diabetes arerelated to similar adverse maternal and perinatal outcomes. Hyperglycemia and other factors associated withdiabetes generate reactive oxygen species that increase DNA damage levels. The aim of this study was to evaluateoxidative DNA damage in lymphocytes of pregnant women with diabetes or mild gestational hyperglycemia.Methods: The study included 111 pregnant women distributed into three groups based on oral glucose tolerancetest (OGTT) and glycemic profiles (GP), as follows: Normal OGTT and GP (control group); Normal OGTT andabnormal GP (mild gestational hyperglycemia group); Abnormal OGTT and GP (diabetic group). Maternal bloodsamples (5–10 mL) were collected and processed for determination of oxidative DNA damage by the comet assay,using Fpg and Endo III enzymes. Urine samples were also collected for determination of 8-OHdG concentrations byELISA.Results: Subjects in the diabetes group presented increased amount of oxidized purines, while mild gestationalhyperglycemia women presented with increased oxidized pyrimidines, compared to the control group.Conclusion: Gestational, overt diabetes and mild gestational hyperglycemia, were all related to increased oxidativeDNA damage. Diabetic pregnant women showed increased level of oxidative DNA damage, perhaps mainly due tohyperglycemia. On the other hand, oxidative DNA damage detected in women with mild gestationalhyperglycemia might be associated with repercussions from obesity, hypertension and/or insulin resistance.Interestingly, the type of DNA base affected seemed to be dependent on the glycemic profile or oxidative stress.

Oxidative stress status and lipid profiles of diabetic pregnant rats exposed to cigarette smoke.

This study aimed to evaluate the oxidative stress status and the concentrations of triglycerides, cholesterol and total proteins of pregnant rats exposed to the association of diabetes and cigarette smoke. Female Wistar rats were randomly distributed in four experimental groups, according to presence or not of diabetes and the exposure or not to cigarette smoke. Diabetes was induced by streptozotocin (40 mg/kg i.v.) and exposure to cigarette smoke was for 30 min, twice a day, for 2 months. At day 21 of pregnancy, blood was collected for total protein, triglyceride, cholesterol and oxidative stress determinations. Data were analysed by ANOVA followed by Student-Newman-Keuls test (P<0.05). The association of diabetes and exposure to cigarette smoke was related to the incidence of hypertriglyceridaemia, and this result was due to the severe diabetes and not to exposure to smoke. There was no alteration to protein metabolism in pregnant rats. Diabetes and cigarette smoke exposure led to the activation of the antioxidant system in an attempt to detoxify the organism in face of high lipid peroxidation, which can be characterized by the determination of reactive substances to thiobarbituric acid.

Neonatally-induced diabetes: lipid profile outcomes and oxidative stress status in adult rats.

BACKGROUND: Experimental models are developed for the purpose of enhancing the understanding of the pathophysiological mechanisms involved in diabetes. Experimental findings lead to the development of treatment strategies to maintain metabolic conditions as close to normal as possible. There are several reports about streptozotocin induced mild diabetes to reproduce type 2 diabetes. However, studies about the interaction among glucose levels, lipid profile, and oxidative stress in these animals remain insufficient. Therefore, this study evaluated these parameters in blood samples from adult Wistar rats treated neonatally with streptozotocin. METHODS: Female newborn Wistar rats received streptozotocin (70 mg/kg, i.p.) on the 5th day of life (n5-STZ). Glycemia was measured in the 3rd and 4th month of life. At the end of the 4th month, blood samples were collected and processed for lipid profile and oxidative stress measurements. RESULTS: Glycemia of n5-STZ rats were significantly higher compared to those of control rats (p<0.05). There was no alteration in levels of total cholesterol, triglycerides, lipid peroxidation (TBARS), SOD activity and GSH-t determination (p>0.05) in the n5-STZ animals when compared to control group. However n5-STZ animals showed a significant decreased HDL-cholesterol rate (p<0.05). CONCLUSION: This streptozotocin-induced diabetes model in rats caused hyperglycemia (120-360 mg/dL), characterizing mild diabetes. This glycemic level led to HDL-lipoprotein alteration, which was not sufficient to impair antioxidant enzyme activities or determination of lipid peroxidation in adult life of rats. Further this experimental investigation contributed to the understanding of different results found in other models for mild/moderate diabetes induction in laboratory animals as well as to a better comprehension of the pathophysiological mechanisms of mild diabetes or hyperglycemia in humans.

Effects of cigarette smoke exposure on pregnancy outcome and offspring of diabetic rats.

A total of 52 female Wistar rats were distributed into four groups: non-diabetic (G1) and diabetic (G2) exposed to filtered air; non-diabetic (G3) and diabetic (G4) exposed to cigarette smoke. Diabetes was induced by streptozotocin (40 mg/kg bodyweight, i.v.). Rats were exposed, for 30 min, to filtered air (control) or to tobacco smoke generated from 10 cigarettes, twice a day, for 2 months. At the end of the 2-month exposure, at day 21 of pregnancy, each rat was anesthetized and humanely killed for laparotomy. Uterine horns were exposed for reproductive performance analysis, fetal and placental weights and placental index. Maternal and fetal data were analysed by ANOVA followed by the Student Newman-Keuls test. Fetal weight classification was assessed by Fisher's exact test. Diabetes and cigarette smoke caused placentomegaly (G4 = 0.65 +/- 0.19 g versus G1 = 0.49 +/- 0.03 g, P < 0.05), increased placental index (G4 = 0.13 +/- 0.03 versus G1 = 0.09 +/- 0.00, P < 0.05) and small fetus rates for pregnancy age (G4 = 88% versus G1 = 23.2%, P < 0.05). These observations show the importance of encouraging pregnant women to attempt cessation of smoking.

Neonatally-induced diabetes: lipid profile outcomes and oxidative stress status in adult rats / Diabete induzido no período neonatal: repercussões no perfil lipídico e avaliação dos marcadores de estresse oxidativo na vida adulta de ratas

BACKGROUND: Experimental models are developed for the purpose of enhancing the understanding of the pathophysiological mechanisms involved in diabetes. Experimental findings lead to the development of treatment strategies to maintain metabolic conditions as close to normal as possible. There are several reports about streptozotocin induced mild diabetes to reproduce type 2 diabetes. However, studies about the interaction among glucose levels, lipid profile, and oxidative stress in these animals remain insufficient. Therefore, this study evaluated these parameters in blood samples from adult Wistar rats treated neonatally with streptozotocin. METHODS: Female newborn Wistar rats received streptozotocin (70 mg/kg, i.p.) on the 5th day of life (n5-STZ). Glycemia was measured in the 3rd and 4th month of life. At the end of the 4th month, blood samples were collected and processed for lipid profile and oxidative stress measurements. RESULTS: Glycemia of n5-STZ rats were significantly higher compared to those of control rats (p<0.05). There was no alteration in levels of total cholesterol, triglycerides, lipid peroxidation (TBARS), SOD activity and GSH-t determination (p>0.05) in the n5-STZ animals when compared to control group. However n5-STZ animals showed a significant decreased HDL-cholesterol rate (p<0.05). CONCLUSION: This streptozotocin-induced diabetes model in rats caused hyperglycemia (120-360mg/dL), characterizing mild diabetes. This glycemic level led to HDL-lipoprotein alteration, which was not sufficient to impair antioxidant enzyme activities or determination of lipid peroxidation in adult life of rats. Further this experimental investigation contributed to the understanding of different results found in other models for mild/moderate diabetes induction in laboratory animals as well as to a better comprehension of the pathophysiological mechanisms of mild diabetes or hyperglycemia in humans.

INTRODUÇÃO: Modelos experimentais são desenvolvidos com propósito de ampliar o entendimento dos mecanismos fisiopatológicos envolvidos no diabete. Os achados experimentais levam ao desenvolvimento de tratamentos alternativos para a manutenção das condições metabólicas normais. Existem vários estudos sobre o diabete induzido por streptozotocin mimetizando o quadro clínico do DM2. No entanto, a interação entre os níveis de glicose, perfil lipídico e estresse oxidativo nestes animais são escassos. Portanto, o objetivo do trabalho foi avaliar estes parâmetros em ratas Wistar adultas com diabete induzido com streptozotocin no período neonatal. MÉTODOS: Fêmeas recém-nascidas receberam streptozotocin (70mg/Kg, ip) no 5º dia de vida (n5-STZ). A glicemia foi medida no terceiro e quarto meses de vida dos animais. No final do quarto mês de vida, amostras de sangue foram coletadas e processadas para a dosagem de lipídios e marcadores de estresse oxidativo. RESULTADOS: A glicemia das ratas do grupo n5-STZ foi significativamente maior comparada às ratas do grupo controle (p<0,05). Não houve alteração nos níveis de colesterol total e triglicérides, peroxidação lipídica (TBARS), atividade da SOD e determinação da GSH-t (p>0,05) nas ratas n5-STZ em relação às ratas do grupo controle. No entanto, houve diminuição significativa no HDL-colesterol (p<0,05). CONCLUSÃO: Este modelo de indução de diabete em ratas causou hiperglicemia (120-360mg/dL), caracterizando o diabete moderado. Essa glicemia levou a alterações no HDL-colesterol, a qual não foi suficiente para prejudicar a atividade das enzimas antioxidantes ou marcadores da peroxidação lipídica na vida adulta. Além disso, esta investigação experimental contribuiu para entender os diferentes resultados encontrados em outros modelos deindução do diabete moderado em animais de laboratório, como também para a melhor compreensão dos mecanismos fisiopatológicos do diabete moderado ou da hiperglicemia em humanos.

Association of diabetes and cigarette smoke exposure on the glycemia and liver glycogen of pregnant Wistar rats / Associação entre diabetes e exposição à fumaça de cigarro sobre a glicemia e glicogênio hepático de ratas Wistar prenhes

PURPOSE: To evaluate cigarette smoke exposure and/or diabetes association effects on the glycemia and liver glycogen levels of pregnant Wistar rats. METHODS: 60 adult rats were randomly distributed into (n=10/group): non-diabetic exposed to filtered air (G1); non-diabetic exposed to cigarette smoke only before pregnancy (G2); non-diabetic exposed to cigarette smoke before and during pregnancy (G3); diabetic exposed to filtered air (G4); diabetic exposed to cigarette smoke only before pregnancy (G5), and diabetic exposed to cigarette smoke before and during pregnancy (G6). Glycemia was determined at days 0 and 21 of pregnancy. Liver samples were collected for liver glycogen determinations. RESULTS: At day 21 of pregnancy, glycemia was higher in G5 and G6 compared to G4 group. G2 (2.43±0.43), G3 (3.20±0.49), G4 (2.62±0.34), G5 (2.65±0.27) and G6 groups (1.94±0.35) presented decreased liver glycogen concentrations compared to G1 (4.20±0.18 mg/100mg liver tissue) (p<0.05). G5 and G6 groups presented decreased maternal weight gain and litter weight. CONCLUSIONS: Severe diabetes and cigarette smoke exposure, alone or associated, caused impairment in liver glycogen storage at term pregnancy. Due to the fact that liver glycogen storages were considered determinant for glucose tolerance, it is relevant to point out a rigid clinical glycemic control and to stop smoking so earlier in pregnancy programming.

OBJETIVO: Avaliar a associação da exposição à fumaça de cigarro e/ou diabete sobre a glicemia e concentrações de glicogênio hepático em ratas Wistar prenhes. MÉTODOS: 60 ratas adultas foram distribuídas aleatoriamente em seis grupos (n=10/grupo): não-diabético exposto ao ar filtrado (G1); não-diabético exposto à fumaça de cigarro antes da prenhez (G2); não-diabético exposto à fumaça de cigarro antes e durante a prenhez (G3); diabético exposto ao ar filtrado (G4); diabético exposto à fumaça de cigarro antes da prenhez (G5); diabético exposto à fumaça de cigarro antes e durante a prenhez (G6). A glicemia foi determinada nos dias 0 e 21 de prenhez. Foram coletadas amostras de fígado para dosagens de glicogênio. RESULTADOS: No 21º dia de prenhez, a glicemia foi maior nos grupos G5 e G6 comparados ao grupo G4. Os grupos G2 (2,43±0,43), G3 (3,20±0,49), G4 (2,62±0,34), G5 (2,65±0,27) e G6 (1,94±0,35) apresentaram concentrações de glicogênio diminuídas comparados ao grupo G1 (4,20±0,18 mg/100mg) (p <0.05). Os grupos G5 e G6 apresentaram ganho de peso materno e peso da ninhada diminuídos. CONCLUSÕES: O diabete grave e a exposição à fumaça de cigarro, sozinhos ou associados, causaram prejuízo no armazenamento de glicogênio na prenhez a termo. Devido ao fato dos estoques de glicogênio serem determinantes para a tolerância à glicose, é imprescindível indicar um rígido controle glicêmico e deixar de fumar antes da gestação.

Association of diabetes and cigarette smoke exposure on the glycemia and liver glycogen of pregnant Wistar rats.

PURPOSE: To evaluate cigarette smoke exposure and/or diabetes association effects on the glycemia and liver glycogen levels of pregnant Wistar rats. METHODS: 60 adult rats were randomly distributed into (n=10/group): non-diabetic exposed to filtered air (G1); non-diabetic exposed to cigarette smoke only before pregnancy (G2); non-diabetic exposed to cigarette smoke before and during pregnancy (G3); diabetic exposed to filtered air (G4); diabetic exposed to cigarette smoke only before pregnancy (G5), and diabetic exposed to cigarette smoke before and during pregnancy (G6). Glycemia was determined at days 0 and 21 of pregnancy. Liver samples were collected for liver glycogen determinations. RESULTS: At day 21 of pregnancy, glycemia was higher in G5 and G6 compared to G4 group. G2 (2.43+/-0.43), G3 (3.20+/-0.49), G4 (2.62+/-0.34), G5 (2.65+/-0.27) and G6 groups (1.94+/-0.35) presented decreased liver glycogen concentrations compared to G1 (4.20+/-0.18 mg/100mg liver tissue) (p<0.05). G5 and G6 groups presented decreased maternal weight gain and litter weight. CONCLUSIONS: Severe diabetes and cigarette smoke exposure, alone or associated, caused impairment in liver glycogen storage at term pregnancy. Due to the fact that liver glycogen storages were considered determinant for glucose tolerance, it is relevant to point out a rigid clinical glycemic control and to stop smoking so earlier in pregnancy programming.

Levels of DNA damage in blood leukocyte samples from non-diabetic and diabetic female rats and their fetuses exposed to air or cigarette smoke.

The objective of the present study was to evaluate DNA damage level in blood leukocytes from diabetic and non-diabetic female Wistar rats exposed to air or to cigarette smoke, and to correlate the findings with levels of DNA damage detected in blood leukocyte samples from their fetuses. A total of 20 rats were distributed into four experimental groups: non-diabetic (control; G1) and diabetic exposed to filtered air (G2); non-diabetic (G3) and diabetic (G4) exposed to cigarette smoke. Rats placed into whole-body exposure chambers were exposed for 30min to filtered air (control) or to tobacco smoke generated from 10 cigarettes, twice a day, for 2 months. Diabetes was induced by a pancreatic beta-cytotoxic agent, streptozotocin (40mg/kgb.w.). At day 21 of pregnancy, each rat was anesthetized and humanely killed to obtain maternal and fetal blood samples for genotoxicity analysis using the alkaline comet assay. G2, G3 and G4 dams presented higher DNA damage values in tail moment and tail length as compared to G1 group. There was a significant positive correlation between DNA damage levels in blood leukocyte samples from G2 and G3 groups (tail moment); G3 and G4 groups (tail length) and G3 group (tail intensity) and their fetuses. Thus, this study showed the association of severe diabetes and tobacco cigarette smoke exposure did not exacerbate levels of maternal and fetal DNA damages related with only diabetes or cigarette smoke exposure. Based on the results obtained and taking into account other published data, maternal diabetes requires rigid clinical control and public health and education campaigns should be increased to encourage individuals, especially pregnant women, to stop smoking.

Evaluation of level of DNA damage in blood leukocytes of non-diabetic and diabetic rat exposed to cigarette smoke.

The objective of the present study was to use the comet assay to evaluate the steady-state level of DNA damage in peripheral blood leukocytes from diabetic and non-diabetic female Wistar rats exposed to air or to cigarette smoke. A total of 20 rats were distributed into four experimental groups (n=5 rats/group): non-diabetic (control) and diabetic exposed to filtered air; non-diabetic and diabetic exposed to cigarette smoke. A pancreatic beta (beta)-cytotoxic agent, streptozotocin (40 mg/kg b.w.) was used to induce experimental diabetes in rats. Rats placed into whole-body exposure chambers were exposed for 30 min to filtered air (control) or to tobacco smoke generated from 10 cigarettes, twice a day, for 2 months. At the end of the 2-month exposure period, each rat was anesthetized and humanely killed to obtain blood samples for genotoxicity analysis using the alkaline comet assay. Blood leukocytes sampled from diabetic rats presented higher DNA damage values (tail moment=0.57+/-0.05; tail length=19.92+/-0.41, p<0.05) compared to control rats (tail moment=0.34+/-0.02; tail length=17.42+/-0.33). Non-diabetic (tail moment=0.43+/-0.04, p>0.05) and diabetic rats (tail moment=0.41+/-0.03, p>0.05) exposed to cigarette smoke presented non-significant increases in DNA damage levels compared to control group. In conclusion, our data show that the exposure of diabetic rats to cigarette smoke produced no additional genotoxicity in peripheral blood cells of female Wistar rats.

Estresse oxidativo e danos de DNA na diabete / Oxidative stress and DNA damage in diabetes

Diabetes mellitus é doença crônica caracterizada por alterações no metabolismo de lipoproteínas, glicose e produção aumentada de espécies reativas do metabolismo do oxigênio (ERMO). Os radicais livres produzidos no organismo como ERMO podem danificar componentes celulares e estão implicados numa variedade de doenças.Podem atacar todos os tipos de macromoléculas, inclusive o DNA. Os efeitos de antioxidantes e de outros agentes que modifiquem os danos de DNA gerados por ERMO têm sido avaliados pelo teste do cometa também conhecido por Single Cell Gel Eletrophoresis assay (SCGE). O ensaio do cometa também é marcador adequado para verificar danos no DNA em pacientes portadores de diabete com estresse oxidativo sistêmico