Electrotherapy for urethral modulation: Are extracellular matrix molecules and growth factors potential targets?

AIMS: To evaluate the expression of genes and proteins involved in the urethral components: vessels, nerves, and extracellular matrix, in female rats after trauma by vaginal distension (VD) and after electrical stimulation therapy (electrotherapy). METHODS: We analyzed the urethras of three groups of 18 female rats 30 days posttrauma by VD: control (no interventions); trauma (animals that had VD); and electrotherapy group (those that had VD and were treated with electrical stimulation). We compared the expression of vascular endothelial growth factor (VEGF), nerve growth factor (NGF), collagen types I and III (COL1a1 and COL3a1), and lysyl-oxidase like 1 (LOXL1) among the groups. Real-time reverse transcription-polymerase chain reaction, Western blot, and immunohistochemistry were used for molecule quantification. We used the Kruskal-Wallis test and analysis of variance for statistical analyses with p < 0.05 for significance. RESULTS: The COL1a1 gene expression was higher in the electrotherapy group than the trauma group (p = 0.036). COL3a1, VEGF, NGF, LOXL1 messenger RNA (mRNA) expression did not differ among the groups (p ≥ 0.05). COL1a1, COL3a1, VEGF, NGF, LOXL1 protein levels did not significantly differ among the groups (p ≥ 0.05) in Western blot analysis or immunohistochemistry assays. CONCLUSIONS: Electrotherapy caused a long-term increase in the COL1a1 mRNA level but did not change COL1a1 protein expression or VEGF, NGF, COL3a1, and LOXL1 genes and proteins in the urethras of rats after trauma by VD.

Kefir administration reduced progression of renal injury in STZ-diabetic rats by lowering oxidative stress.

This study aimed at assessing the effects of Kefir, a probiotic fermented milk, on oxidative stress in diabetic animals. The induction of diabetes was achieved in adult male Wistar rats using streptozotocin (STZ). The animals were distributed into four groups as follows: control (CTL); control Kefir (CTLK); diabetic (DM) and diabetic Kefir (DMK). Starting on the 5th day of diabetes, Kefir was administered by daily gavage at a dose of 1.8 mL/day for 8 weeks. Before and after Kefir treatment, the rats were placed in individual metabolic cages to obtain blood and urine samples to evaluate urea, creatinine, proteinuria, nitric oxide (NO), thiobarbituric acid reactive substances (TBARS) and C-reactive protein (CRP). After sacrificing the animals, the renal cortex was removed for histology, oxidative stress and NOS evaluation. When compared to CTL rats, DM rats showed increased levels of glycemia, plasmatic urea, proteinuria, renal NO, superoxide anion, TBARS, and plasmatic CRP; also demonstrated a reduction in urinary urea, creatinine, and NO. However, DMK rats showed a significant improvement in most of these parameters. Despite the lack of differences observed in the expression of endothelial NO synthase (eNOS), the expression of inducible NO synthase (iNOS) was significantly lower in the DMK group when compared to DM rats, as assessed by Western blot analysis. Moreover, the DMK group presented a significant reduction of glycogen accumulation within the renal tubules when compared to the DM group. These results indicate that Kefir treatment may contribute to better control of glycemia and oxidative stress, which is associated with the amelioration of renal function, suggesting its use as a non-pharmacological adjuvant to delay the progression of diabetic complications.

Impaired glucose tolerance plus hyperlipidaemia induced by diet promotes retina microaneurysms in New Zealand rabbits.

UNLABELLED: With the increasing prevalence of diabetes mellitus and metabolic syndrome worldwide, experimental models are required to better understand the pathophysiology and therapeutic approaches to preserve pancreatic beta cells, attenuate atherosclerosis and protect target organs. The aims of this study were to develop an experimental model of impaired glucose tolerance combined with hypercholesterolaemia induced by diet and assess metabolic alterations and target organ lesions. New Zealand male rabbits were fed high-fat/high-sucrose (10/40%) and cholesterol-enriched diet for 24 weeks, when they were sacrificed. Biochemistry, fundus photographs with fluorescein angiography and pathological analyses were performed. Cholesterol-fed and normal animals of same age were compared. RESULTS: The animals with diet-induced impaired glucose tolerance combined with hypercholesterolaemia gained weight, increased blood glucose, total cholesterol, LDL-C and triglycerides and decreased HDL-C (P < 0.05 vs. baseline). Fructosamine levels and the homeostasis model assessment of insulin resistance (HOMA-IR) index were increased, while there was a reduction in the HOMA-ß (P < 0.05 for all vs. baseline). Histomorphologic findings of this model were aortic atherosclerosis, hepatic steatofibrosis and glomerular macrophage infiltration. Early clinical features of diabetic retinopathy with hyperfluorescent dots consistent with presence of retina microaneurysms were seen since week 12, progressing up to the end of the experiment (P < 0.0005 vs. baseline and 12 weeks). Our model reproduced several metabolic characteristics of human diabetes mellitus and promoted early signs of retinopathy. This non-expensive model is suitable for studying mechanistic pathways and allowing novel strategic approaches.

Digitoxin Attenuates Heart Failure, Reduces Myocardial Hypertrophy, and Preserves the Calcium-Binding Proteins in Infarcted Rats.

We previously showed that digitoxin prolongs the survival of rats with heart failure due to myocardial infarction (MI). In this study, we evaluated the effect of digitoxin on myocardial structure, ventricular function, and proteins involved in calcium kinetics. Seventy-two rats with MI >35% of the left ventricle were randomly assigned to 4 treatment groups: sham (n = 15), digitoxin (n = 11), infarction (n = 20), and infarction + digitoxin (n = 26). The rats were assessed 120 days after surgery by echocardiogram, hemodynamics, papillary muscle mechanics, collagen content, cardiomyocyte nuclear volume, and Western blot analysis of proteins involved in calcium kinetics. Digitoxin was administered via the rat chow. Two-way analysis of variance was used for comparisons. Myocardial infarction caused inotropic impairment, pulmonary congestion, increase of nuclear volume, myocardial collagen, and Na+/Ca2+ exchanger levels, and decreased SERCA2 and phosphorylated phospholamban levels. Treatment with digitoxin showed improvements in cardiac remodeling, inotropism, ventricular performance, pulmonary congestion, collagen accumulation, nuclear volume, and proteins involved in calcium kinetics. In rats with heart failure due to MI, long-term treatment with digitoxin attenuates congestive heart failure, mitigates myocardial remodeling and contractile impairment, and preserves myocardial levels of proteins involved in calcium kinetics.

Exercise training prevents beta-adrenergic hyperactivity-induced myocardial hypertrophy and lesions.

BACKGROUND: Sustained beta-adrenoreceptor activation promotes cardiac hypertrophy and cellular injury. AIMS: To evaluate the cardioprotective effect of exercise on damage induced by beta-adrenergic hyperactivity. METHODS: Male Wistar rats were randomised into four groups (n=8 per group): sedentary non-treated control (C), sedentary treated with isoproterenol 0.3 mg/kg/day administered subcutaneously for 8 days (I), exercised non-treated (E) and exercised plus isoproterenol administered during the last eight days of exercise (IE). Exercised animals ran on a treadmill for 1 h daily 6 times a week for 13 weeks. RESULTS: Isoproterenol caused increases in left ventricle (LV) wet and dry weight/body weight ratio, LV water content and cardiomyocyte transverse diameter. Additionally, isoproterenol induced severe cellular lesions, necrosis, and apoptosis, increased collagen content and reduced capillary and fibre fractional areas. Notably, all of these abnormalities were completely prevented by exercise. CONCLUSION: Our data have demonstrated that complete cardioprotection is possible through exercise training; by preventing beta-adrenergic hyperactivity-induced cardiac hypertrophy and structural injury.

Damaging effects of intense repetitive treadmill running on murine intestinal musculature.

Several gastrointestinal symptoms associated with prolonged intense exercise (IE) have been reported, although the mechanisms underlying its effects on the intestine remain poorly understood. The aim of the present study was to investigate whether IE may induce oxidative stress in the intestine, as well as its possible relationship with intestinal signaling impairments, leading to contractile disturbances. C57BL/6 mice were submitted to 4 days (EX.4D) and 10 days (EX.10D) of IE. The daily exercise session consisted of a running session until exhaustion, with the treadmill speed set at 85% of each animal's maximum velocity. The decrease in exhaustion time was exponential, and the reduction in the maximum velocity, as assessed by an incremental test, was higher in EX.4D than in EX.10D animals. The ileum mucosa layer was partially destroyed after 4 days of IE, where 37% and 11% muscle layer atrophies were observed in EX.4D and EX.10D animals, respectively. Ileum contractility was significantly impaired in the EX.4D animal group, with reduced efficacy for carbachol, bradykinin, and KCl signaling associated with a decrease in lipid peroxidation and with no alteration of protein oxidation. Intestinal myocytes from EX.10D animals displayed areas containing structurally disorganized mitochondria, which were associated with increased levels of protein oxidation, without alteration of contractility, except for a reduction in the potency of bradykinin signaling. Finally, no clear relationship between ileum contractility and oxidative stress was shown. Together, these results argue in favor of significant functional, biochemical, and morphological disturbances caused by exercise, thus demonstrating that intestinal tissue is very sensitive to exercise.

Habitual exercise program protects murine intestinal, skeletal, and cardiac muscles against aging.

Aging and aerobic exercise are two conditions known to interfere with health and quality of life, most likely by inducing oxidative stress to the organism. We studied the effects of aging on the morphological and functional properties of skeletal, cardiac, and intestinal muscles and their corresponding oxidative status in C57BL/6 mice and investigated whether a lifelong moderate exercise program would exert a protective effect against some deleterious effects of aging. As expected, aged animals presented a significant reduction of physical performance, accompanied by a decrease of gastrocnemius cross-sectional area and cardiac hypertrophy. However, most interesting was that aging dramatically interfered with the intestinal structure, causing a significant thickening of the ileum muscular layer. Senescent intestinal myocytes displayed many mitochondria with disorganized cristae and the presence of cytosolic lamellar corpuscles. Lipid peroxidation of ileum and gastrocnemius muscle, but not of the heart, increased in aged mice, thus suggesting enhanced oxidative stress. With exception of the intestinal muscle responsiveness, animals submitted to a daily session of 60 min, 5 days/wk, at 13 up to 21 m/min of moderate running in treadmill during animal life span exhibited a reversion of all the observed aging effects on intestinal, skeletal, and heart muscles. The introduction of this lifelong exercise protocol prevented the enhancement of lipid peroxidation and sarcopenia and also preserved cellular and ultracellular structures of the ileum. This is the first time that the protective effect of a lifelong regular aerobic physical activity against the deleterious effects of aging on intestinal muscle was demonstrated.

Comparison between the effects of soy milk and non-fat cow milk on lipid profile and lipid peroxidation in patients with primary hypercholesterolemia.

OBJECTIVE: This study assessed whether the consumption of soy milk could add significantly to the lipid profile and lipid peroxidation in comparison with non-fat milk. METHODS: A double-blind, randomized, crossover study was conducted on 60 outpatients with primary hypercholesterolemia following a lipid-lowering diet for at least 6 wk. Lipid profile was obtained at baseline and at 6 and 12 wk, with the patients randomly assigned to receive initially 1 L/d of soy milk or non-fat cow milk for 6 wk. Lipid peroxidation was estimated by plasma thiobarbituric reactive substances. Apolipoprotein E genotypes were examined by polymerase chain reaction restriction fragment length polymorphism. RESULTS: The soy milk diet was associated with low-density lipoprotein cholesterol reduction (baseline = 157 +/- 5 mg/dL; soy milk = 148 +/- 4 mg/dL; non-fat cow milk = 158 +/- 4 mg/dL; P < 0.05, soy milk versus other treatments) and with high-density lipoprotein cholesterol increase (baseline = 58 +/- 2 mg/dL; soy milk = 62 +/- 2 mg/dL; non-fat cow milk = 57 +/- 2 mg/dL; P < 0.05, soy milk versus other treatments). In addition, plasma thiobarbituric reactive substances were reduced by the soy milk diet (baseline = 1.82 +/- 0.12 nM/L; soy milk = 1.49 +/- 0.09 nM/L; non-fat cow milk = 1.91 +/- 0.11 nM/mL; P < 0.05, soy milk versus non-fat cow milk). Changes in lipid profile were not influenced by APOE genotypes. CONCLUSIONS: These results indicate that soy milk as part of a lipid-lowering diet has beneficial effects in improving lipid profile and reducing lipid peroxidation.

Euterpe oleracea (açai) modifies sterol metabolism and attenuates experimentally-induced atherosclerosis.

AIM: Euterpe Oleracea (açai) is a fruit from the Amazon region whose chemical composition may be beneficial for individuals with atherosclerosis. We hypothesized that consumption of Euterpe Oleracea would reduce atherosclerosis development by decreasing cholesterol absorption and synthesis. METHODS: Male New Zealand rabbits were fed a cholesterol-enriched diet (0.5%) for 12 weeks, when they were randomized to receive Euterpe Oleracea extract (n = 15) or water (n = 12) plus a 0.05% cholesterol-enriched diet for an additional 12 weeks. Plasma phytosterols and desmosterol were determined by ultra-performance liquid chromatography and mass spectrometry. Atherosclerotic lesions were estimated by computerized planimetry and histomorphometry. RESULTS: At sacrifice, animals treated with Euterpe Oleracea had lower levels of total cholesterol (p =0.03), non-HDL-cholesterol (p = 0.03) and triglycerides (p = 0.02) than controls. These animals had smaller atherosclerotic plaque area in their aortas (p = 0.001) and a smaller intima/media ratio (p = 0.002) than controls, without differences in plaque composition. At the end of the study, campesterol, ß-sitosterol, and desmosterol plasma levels did not differ between groups; however, animals treated with Euterpe Oleracea showed lower desmosterol/campesterol (p = 0.026) and desmosterol/ ß-sitosterol (p =0.006) ratios than controls. CONCLUSIONS: Consumption of Euterpe Oleracea extract markedly improved the lipid profile and attenuated atherosclerosis. These effects were related in part to a better balance in the synthesis and absorption of sterols.

The role of metalloendopeptidases in oropharyngeal carcinomas assessed by tissue microarray.

The goal of this study was to investigate the expression of some metalloendopeptidases in squamous cell carcinomas of the oropharynx as well as its relation to histological differentiation, staging of disease, and prognosis. Paraffin blocks from 21 primary tumors were obtained from archives of the Department of Pathology, Paulista Medical School, Federal University of Sao Paulo, UNIFESP/EPM. Immunohistochemistry was used to detect the expression of EP24.15 and EP24.16 by means of tissue microarrays. Expression of EP24.15 or EP24.16 was not correlated with the stage of disease, histopathological grading or recurrence in squamous cell carcinomas of the oropharynx. In summary, our results support the notion that EP24.15 and EP24.16 are expressed in carcinoma of the oropharynx; however, these do not appear to be suitable biomarkers for histological grading, disease stage or recurrence as depicted by tissue microarrays and immunohistochemistry.

Protective effects of green tea against hepatic injury induced by high-cholesterol diet in rats: histopathological analysis, oxidative DNA damage and COX-2 expression.

PURPOSE: The goal of this study was to investigate whether daily administration of green tea is able to protect the liver injury induced by cholesterol. METHODS: Male Wistar rats (n = 24) were distributed into four groups: group 1, negative control; group 2, cholesterol at 1% (w/w) in the diet treated for 5 weeks; group 3, cholesterol at 1% treated for 5 weeks and green tea at 1% (w/v) in drinking water in the last week only and group 4, cholesterol and green tea at 1% in drinking water for 5 weeks. RESULTS: The results pointed out that treatment with green tea in the last week (group 3) showed mild degenerative changes of liver tissue in cholesterol exposed group when compared to group 2. Green tea aqueous extract was not able to reduce cholesterol levels, that is, no significant statistical differences (p > 0.05) were noticed when compared to positive control group. Nevertheless, green tea was able to decrease oxidative deoxyribonucleic acid (DNA) damage either to peripheral blood or to liver cells as depicted by significant statistical differences (p < 0.05) in the mean tail moment between groups treated with green tea and cholesterol and cholesterol only. Furthermore, histomorphometric analysis of COX-2 expression revealed that in groups exposed to green tea they were significantly decreased (p < 0.05), regardless of time exposure adopted. CONCLUSION: Taken together, our results suggest that daily administration of green tea for at least 7 days displays some preventive properties as indicated by COX-2 downregulation and decreased oxidative DNA damage.

Resident peritoneal inflammatory cells are pivotal in the development of experimental atherosclerosis.

AIM: Based on evidence that ionizing radiation can ameliorate chronic and autoimmune diseases in patients and experimental animals, we investigated the effects of radiation on the induction and development of experimental atherogenesis. METHODS: Male New Zealand rabbits were divided into 5 groups and given an atherogenic diet for 90 days. Peritoneal and thoracic areas (9 Gy) were irradiated on the 1st and 45th days for groups 1 and 2, the 45th day for groups 3 and 4, and not at all for group 5. Prior to irradiation, the peritoneal cavity of animals from groups 1 and 3 was washed with buffered saline. Cells collected by peritoneal washing were reinfused into the peritoneal cavity of the same animal after irradiation. Animals from groups 2 and 4 were intraperitoneally injected with saline as a control. RESULTS: Despite similar lipid profiles among the experimental groups, the percentage of aortas covered by plaques was remarkably reduced (p<0.001) among animals submitted to irradiation (groups 2 and 4). These differences were completely abolished in irradiated animals reconstituted with their own peritoneal cells. CONCLUSIONS: These findings point to an important role of resident inflammatory peritoneal cells in experimental atherogenesis.

Association of lipoprotein lipase D9N polymorphism with myocardial infarction in type 2 diabetes: the genetics, outcomes, and lipids in type 2 diabetes (GOLD) study.

The association of polymorphisms affecting lipid metabolism with the risk of myocardial infarction (MI) in type 2 diabetes mellitus was investigated. The Genetics, Outcomes and Lipids in type 2 Diabetes (GOLD) Study is a prospective, multicenter study, conducted on 990 patients presenting diabetes and MI (n=386), or diabetes without previous manifestation of stroke, peripheral or coronary arterial disease (n=604), recruited from 27 institutions in Brazil. APO A1 (A/G -75 and C/T +83) and APO C3 (C/G 3'UTR) non-coding sequences, CETP (Taq 1B), LPL (D9N), APO E (epsilon2, epsilon3, epsilon4,), PON-1 (Q192R), and two LCAT variants Arg(147)-->Trp and Tyr(171)-->Stop were tested by PCR-RFLP. There was a higher prevalence of LPL DN genotype (19% vs.12%, p=0.03) and a higher frequency of the N allele (11% vs. 7%) among subjects with MI when compared to controls, with an odds ratio of MI for carriers of 9N allele of 2.46 (95% CI=1.79-3.39, p<0.0001). This association was present in men and women, in non-smokers and in hypertensive patients. A logistic regression model including gender, duration of diabetes, systolic blood pressure, HDL-C, left ventricle hypertrophy and D9N polymorphism showed that the latter still remained significantly associated with MI (OR=1.50, 95% CI=1.02-2.25, p=0.049). These findings suggest that D9N polymorphism can be a useful risk marker for myocardial infarction and that further potential candidate genes should be screened for exploratory analysis and for future therapeutic intervention in diabetes.

High glucose levels abolish antiatherosclerotic benefits of ACE inhibition in alloxan-induced diabetes in rabbits.

Renin-angiotensin system activation is recognized to play an important role in atherosclerosis. This study aimed to verify the antiatherosclerotic effects of ACE inhibition on an experimental model of diabetes and hypercholesterolemia. Diabetes was induced in New Zealand male rabbits with a single dose of alloxan (100 mg/kg, i.v.), and, according to plasma glucose levels obtained after 1 week, the animals were divided into 2 groups (> or =250 mg/dL or <250 mg/dL). Each group was randomly assigned to receive or not quinapril (30 mg/d) added to a 0.5% cholesterol-enriched diet. Animals with high glucose levels at 1 week and that remained high after 12 weeks presented higher triglyceride levels (P < 0.02 versus basal). Those initially hyperglycemic but presenting <250 mg/dL glucose at the end of study formed an additional group. Plasma ACE activity was lower in quinapril-treated animals (P < 0.01 versus untreated groups). However, aorta intima/media ratio and intima area were lower only in the subgroups of quinapril-treated animals with low glucose levels (P < 0.05). Our results support the hypothesis that high plasma glucose may abolish the antiatherosclerotic effect of ACE inhibitors.

Early benefits of pravastatin to experimentally induced atherosclerosis.

There is little information regarding the time of hypolipidemic treatment of changes in atherosclerotic plaque, tissue cholesterol content, and also for the recovery of endothelial function. To assess the early effects of lipid-lowering treatment on these parameters, six groups of New Zealand male rabbits were studied. Animals in groups I and II were fed regular chow; groups III and IV received a 12-week 0.5% cholesterol diet followed by 12 weeks of 0.05% cholesterol diet. Finally, groups V and VI were fed a 12-week 0.5% cholesterol diet and were then shifted to a regular diet for 12 weeks. During the last four weeks, the rabbits in groups I, III, and V received low-dose pravastatin (2 mg/day), added to the diet. Group IV animals had the highest cholesterol plasma levels (vs. groups I, II, III, and V, p < 0.01) and presented atherosclerotic plaques in a more advanced stage. Nonatherogenic diet was insufficient to restore endothelial function in animals previously fed cholesterol-enriched diets (groups IV and VI). Conversely, pravastatin treatment promoted significant improvement in endothelial function and reduced the progression of atherosclerosis. Marked increase in cholesterol content was seen in aorta and liver in response to the atherogenic diet. However, neither treatment with pravastatin nor nonatherogenic diet was capable of modifying the tissue cholesterol content. Our study supports the hypothesis that the early use of statins can attenuate the progression of atherosclerosis and ameliorate endothelial function. In addition, significant changes in the tissue cholesterol pool probably need a longer period of treatment.

Hipertensão e dislipidemias / Hypertension and dyslipidemia

A hipertensão e a aterosclerose constituem uma condição alarmante para a morbidade e mortalidade dos pacientes renais cronicos. Aumento na prevalência da nefropatia hipertensiva como causa de doença renal em estágio final tem sido relatado nos EUA e na Europa. Nestes pacientes, a mortalidade cardiovascular é 10 a 20 vezes maior do que a observada na população geral e está presente em aproximadamente metade dos pacientes em tratamento dialetico. A hipertensão acelera o desenvolvimento da aterosclerose e as dislipidemias agravam a doença renal hipertensiva, a hipertrofia miocordica e os eventos cardiovasculares do paciente hipertenso. O tratamento da hipertensão arterial pode modificar o perfil lipidico e a aterosclerose induzida pela hiperlipidemia. Da mesma forma, o tratamento hipolipemiante pode reduzir a pressão arterial, atenuar a disfunção endotelial da aterosclerose e diminuir o dano renal