Moderate-intensity exercise training improves long-term memory in fructose-fed rats

Abstract Aim: Animal disease model studies are widely used to show the effectiveness of physical exercise to improve cognitive function. Thus far, few studies are investigating the effects of exercise training on memory performance in fructose feed animals. Method: The present study investigated the effects of physical exercise protocol carried out with three weekly sessions, on the short and long-term memory performance of animals fed with fructose. Male Wistar rats were divided into sedentary (SD); sedentary+fructose (SDF); trained (TR); trained+fructose (TRF). Treadmill running sessions consisted of a five-minute warm-up at 20% maximum speed (MS) followed by 40 minutes at 40% MS and a 5-minute cool-down at 20% MS. Sessions were carried out three days a week (Monday, Wednesday, and Friday) for six weeks. Object Recognition Test was used to evaluate short and long-term memory. Results: The access to fructose altered food intake and drinking volume, as fructose-fed animals had lower food intake (SDF: -27% and TRF: -24%) and higher drinking volume (SDF: +49% and TRF: +45%) than an animal which drank water. Trained groups had lower epididymal fat pad compared to their sedentary counterparts (TR: -30% and TRF: -11%). In addition, TR and TRF had an improvement in glucose tolerance. Regarding memory performance, neither fructose intake nor exercise training influenced short-term memory. On the other hand, long-term memory was enhanced by exercise training. An improvement of about 39% was observed for TR and the largest effect was seen for TRF, which improved long-term memory in 76%. Conclusion: In conclusion, moderate-intensity exercise training, carried out three days a week, for six weeks was effective to improve long-term memory in fructose-fed rats. This result was related neither to the visceral fat amount nor to the glucose metabolism. Further studies should considerer the investigation regarding cerebral areas, associated with memory that might be adapted facing physical exercise.

Insulin-like growth factor binding protein-1, non-alcoholic fatty liver disease, and its relationship with fructose consumption in children with obesity

Background Over consumption of added sugar is associated with obesity, non-alcoholic fatty liver disease (NAFLD), and insulin resistance (IR). Objective The objective of the study was to study the insulin-like growth factor binding protein-1 (IGFBP-1) and NAFLD and their relationship with fructose consumption in children with obesity. Methods A cross-sectional study was carried out in children 6-11 years old with obesity. Anthropometric measurements, fructose consumption, glucose, lipid profile, insulin, and IGFBP-1 levels were evaluated; the homeostatic model assessment of IR (HOMA-IR) was used. NAFLD was evaluated by ultrasound. Results We studied 83 children with a mean age of 9.2 ± 1.3 years. About 93% of the girls presented IR and lower levels of IGFBP-1 (p = 0.0001). The group with the lower levels of IGFBP-1 had higher HOMA-IR (p = 0.000002); IGFBP-1 was associated with fructose consumption (r = −0.25; p = 0.03), body mass index (BMI) (r=−0.42; p = 0.02), and HOMA-IR (r=−0.61; p = 0.002). About 81% of the children were classified as having mild or moderate/severe NAFLD, and these groups had higher HOMA-IR (p = 0.036) and fructose consumption (p = 0.0014). Conclusions The girls had more metabolic alterations. The group with lower levels of IGFBP-1 (hepatic IR) was associated with higher BMI, HOMA-IR, and fructose consumption; the group with higher severity of NAFLD showed higher HOMA-IR and fructose consumption.

Use of alternative extender added of fructose aiming the cryopreservation of boar semen / Utilização de diluente alternativo acrescido de frutose visando à criopreservação de sêmen suíno

This study aimed to analyze skimmed milk powder (SMP) and fructose in a new cooling curve to freeze boar semen. A total of 49 semen samples from seven boars were cryopreserved using the new curve with addition of glucose and fructose to the refrigerating diluents: Beltsville Thawing Solution (BTS + G; BTS + F) and Skimmed milk powder (SMP + G; SMP + F), totaling four experimental groups for analysis. To finish the curve, aliquots of semen were packaged in 0.5 ml straws and kept in liquid nitrogen. During the cooling curve, SMP mean spermatic vigor and motility were greater than the BTS (p < 0.05). After thawing, a decrease of spermatic force and motility in both extenders was observed, where the BTS presented spermatic vigor (2.1 ± 0.55) and motility (38 ± 21.8), presenting better results (p < 0.05). There was no statistical difference between sugars added to the BTS and SMP in spermatic force and motility (p > 0.05), although the use of fructose allowed an equalization of motility between the SMP and BTS (p > 0.05). Functionality of membrane was better preserved with the addition of fructose, in both extenders. The rate of sperm viability was significantly higher in extender containing glucose and SMP (71.8 ± 12.5). The percentage of intact acrosome was higher on the treatment containing glucose, independent of the extender (BTS + G: 81.8 ± 7.2, SMP + G: 81.4 ± 14.2). To conclude, the results suggest that the BTS is still the best option to cryopreserve and fructose could be used in boar semen cryopreservation in new cooling curve.(AU)

O presente trabalho analisou o emprego do leite em pó desnatado (LPD) adicionado de frutose em uma nova curva de resfriamento para criopreservação de sêmen suíno. Um total de 49 ejaculados, de sete varrões foram criopreservados utilizando a nova curva de resfriamento com glicose e frutose adicionada aos diluentes Beltsville Thawing Solution (BTS + D; BTS + F) e Leite em pó desnatado (LPD + D; LPD + F), totalizando quatro grupos experimentais para análises. Ao final da curva, as alíquotas de sêmen foram envasadas em palhetas de 0,5 mL e mantidas em nitrogênio líquido. Durante a curva de resfriamento, a média de vigor e motilidade espermática do LPD foi maior do que do BTS (p < 0.05). Após descongelação, observou-se queda do vigor e motilidade em ambos diluentes, com o BTS apresentando melhores resultados de vigor (2,1 ± 0,55) e de motilidade (38 ± 21,8) (p < 0,05). Entretanto, o uso da frutose permitiu equiparação dos valores da motilidade entre LPD e BTS (p > 0,05). A funcionalidade de membrana foi melhor preservada com adição da frutose, em ambos os diluentes. Os dados de vitalidade espermática foram significativamente maiores no diluente contendo glicose e LPD (71,8 ± 12,5). A porcentagem de acrossomas intactos foi maior no tratamento que continha glicose, independentemente do diluente utilizado (BTS + G: 81,8 ± 7,2, SMP + G: 81,4 ± 14,2). Os resultados obtidos indicaram que o BTS, ainda é a melhor opção de criopreservação e que a frutose pode ser utilizada para criopreservação de sêmen de varrão na nova curva de resfriamento.(AU)

Efecto inotrópico y cronotrópico del propranolol sobre aurículas extraídas de ratas con insulina-resistencia inducida por fructosa / Inotropic and chronotropic effects of propranolol in isolated atrium of rats with fructose-induced insulin-resistance

La insulina-resistencia (IR) es una deficiencia metabólica asociada princi palmente con diabetes tipo 2 y comúnmente relacionada a la etiopatogenia de enfermedades cardiovasculares, siendo el factor determinante del síndrome metabólico. La investigación pretende conocer los efectos cronotrópico e inotrópico del propranolol sobre aurículas de ratas IR. Para ello, 16 ejemplares Sprague-Dawley, fueron divididos en Grupo control, alimentado ad libitum con alimento para perros Perrarina® y Grupo experimental, alimentado con Perrarina®-manteca vegetal, y suministro de agua con fructosa (20%)-sacarosa (20%) durante ocho meses. Al finalizar este periodo, se verificó la insulina-resistencia y las aurículas extraídas se mantuvieron en solución Krebs (37ºC, pH 7,4; 95% O2 - 5% CO2), en baño de órganos aislados marca Letica®, conectado a un polígrafo Grass®, registrándose la frecuencia de los latidos y evaluando las diferencias a través de la prueba t de Student (grado de significancia p<0,05). Se establecieron curvas dosis-respuesta acumulativas con isoproterenol y previa incubación de 15 minutos con propranolol (1x10 -6 M), registrándose un efecto cronotrópico negativo en el grupo control mas no así en las ratas IR, estableciéndose diferencias significativas entre el porcentaje de incremento de los latidos/seg en ambos grupos (Control 58,81±4,08; IR 68,84±4,16; p<0,001). La máxima fuerza de contracción auricular alcanzada por el grupo IR con propranolol (278,47±11,22), generó diferencias significativas (p<0,001), en comparación con el grupo control (42,60±3,13), evidenciándose que el propranolol no generó bloqueo sobre los receptores beta-adrenérgicos auriculares de las ratas insulina-resistentes.

Insulin resistance (IR) is a metabolic deficiency associated with type 2 diabe tes and commonly related to the pathogenesis of cardiovascular diseases, being the determining factor of the metabolic syndrome. This research aims to understand the chronotropic and inotropic effects of Propranolol in isolated atrium of rats with fructose-induced insulin-resistance. For this reason, 16 male Sprague-Dawley rats were assigned to two groups and given ad libitum access to one of the following diets: Perrarina® dog chow or Perrarina® dog chow supplemen ted with vegetable shortening and with fructose (20%) and sucrose (20%) added to the water supply. Both groups were maintained on their respective dietary regimens for eight months. At the end of this period insulin resistance was verified by routine blood test. The rat hearts were rapidly removed, and the atria were dissected and kept in Krebs solutions (37ºC, pH 7.4; 95% O2 - 5% CO2) in an isolated organ bath Letica®, connected to a polygraph Grass®, registering atria frequency. The Student ́s t-test was used to evaluate statistical differences between the two groups (p<0.05). Cumulative dose-response curves with isoproterenol were established in basal condition, and after fifteen minutes of pre-incubation with propranolol (1x10 -6 M). A significant positive chronotropic effect was observed in IR rats (8.84±4.16 vs 58.81±4.08 beats/sec of control; p<0.001). The maximum force of atrial contraction after pre-incubation with propranolol was significantly higher in the IR group (278.47±11.22 atrial contraction percentage; p<0.001). These findings suggest that a blunted response of atrial β-adrenoceptor to propranolol exists in rats with fructose-induced insulin-resistance.

Exercise training prevents increased intraocular pressure and sympathetic vascular modulation in an experimental model of metabolic syndrome

The present study aimed to study the effects of exercise training (ET) performed by rats on a 10-week high-fructose diet on metabolic, hemodynamic, and autonomic changes, as well as intraocular pressure (IOP). Male Wistar rats receiving fructose overload in drinking water (100 g/L) were concomitantly trained on a treadmill for 10 weeks (FT group) or kept sedentary (F group), and a control group (C) was kept in normal laboratory conditions. The metabolic evaluation comprised the Lee index, glycemia, and insulin tolerance test (KITT). Arterial pressure (AP) was measured directly, and systolic AP variability was performed to determine peripheral autonomic modulation. ET attenuated impaired metabolic parameters, AP, IOP, and ocular perfusion pressure (OPP) induced by fructose overload (FT vs F). The increase in peripheral sympathetic modulation in F rats, demonstrated by systolic AP variance and low frequency (LF) band (F: 37±2, 6.6±0.3 vs C: 26±3, 3.6±0.5 mmHg2), was prevented by ET (FT: 29±3, 3.4±0.7 mmHg2). Positive correlations were found between the LF band and right IOP (r=0.57, P=0.01) and left IOP (r=0.64, P=0.003). Negative correlations were noted between KITT values and right IOP (r=-0.55, P=0.01) and left IOP (r=-0.62, P=0.005). ET in rats effectively prevented metabolic abnormalities and AP and IOP increases promoted by a high-fructose diet. In addition, ocular benefits triggered by exercise training were associated with peripheral autonomic improvement.

Antioxidant and anti hyperglycemic role of wine grape powder in rats fed with a high fructose diet

BACKGROUND: Metabolic syndrome is a growing worldwide health problem. We evaluated the effects of wine grape powder (WGP), rich in antioxidants and fiber, in a rat model of metabolic syndrome induced by a high fructose diet. We tested whether WGP supplementation may prevent glucose intolerance and decrease oxidative stress in rats fed with a high fructose diet. METHODS: Male Sprague-Dawley rats weighing 180 g were divided into four groups according to their feeding protocols. Rats were fed with control diet (C), control plus 20 % WGP (C + WGP), 50 % high fructose (HF) or 50 % fructose plus 20 % WGP (HF + WGP) for 16 weeks. Blood glucose, insulin and triglycerides, weight, and arterial blood pressure were measured. Homeostasis model assessment (HOMA) index was calculated using insulin and glucose values. A glucose tolerance test was performed 2 days before the end of the experiment. As an index of oxidative stress, thio-barbituric acid reactive substances (TBARS) level was measured in plasma and kidney, and superoxide dismutase was measured in the kidney. RESULTS: Thiobarbituric acid reactive substances in plasma and renal tissue were significantly higher when compared to the control group. In addition, the area under the curve of the glucose tolerance test was higher in HF fed animals. Furthermore, fasting blood glucose, plasma insulin levels, and the HOMA index, were also increased. WGP supplementation prevented these alterations in rats fed with the HF diet. We did not find any significant difference in body weight or systolic blood pressure in any of the groups. CONCLUSIONS: Our results show that WGP supplementation prevented hyperglycemia, insulin resistance and reduced oxidative stress in rats fed with HF diet. We propose that WGP may be used as a supplement in human food as well.

Anti-diabetic effect of a combination of andrographolide-enriched extract of Andrographis paniculata (Burm f.) Nees and asiaticoside-enriched extract of Centella asiatica L. in high fructose-fat fed rats.

Traditionally, a combination of medicinal plants is commonly used for lowering blood glucose in diabetic patients in order to provide additional benefits of the single drug. A. paniculata and C. asiatica are two traditional medicines form South Asian and Southeast Asain countries consumed by people for treating daibates mellitus and its complications. Hyperglycemia in the rats was stimulated by high fructose-fat diet that consists of 36% fructose, 15% lard, and 5% egg yolks in 0.36 g/200 g body weight for 70 days. The rats were orally administered with the combination of andrographolide-enriched extract of A. paniculata (AEEAP) leaves and asiaticoside-enriched extract of C. asiatica (AEECA) herbs from day 70 for 7 days. Antidiabetic activity was evaluated by estimating mainly the blood glucose levels and other parameters such as HDL, LDL, cholesterol and triglyceride. The results showed that combination at the ratio of 70:30 exhibited a promosing antidiabetic effect in high-fat-fructose-fed rat, and exhibited sinergistic effects on blood cholesterol and HDL levels. It can be concluded that its antidiabetic effect was better than that of single treatment of AEEAP or AEECA. That combination was also potential to develop as a blood glucose-lowering agent for diabetic patients.

Alleviation of metabolic abnormalities induced by excessive fructose administration in Wistar rats by Spirulina maxima.

Background & objectives: Diabetes mellitus is a metabolic disorder characterized by hyperglycaemia. Several natural products have been isolated and identified to restore the complications of diabetes. Spirulina maxima is naturally occurring fresh water cyanobacterium, enriched with proteins and essential nutrients. The aim of the study was to determine whether S. maxima could serve as a therapeutic agent to correct metabolic abnormalities induced by excessive fructose administration in Wistar rats. Methods: Oral administration of 10 per cent fructose solution to Wistar rats (n=5 in each group) for 30 days resulted in hyperglycaemia and hyperlipidaemia. Aqueous suspension of S. maxima (5 or 10%) was also administered orally once daily for 30 days. The therapeutic potential of the preparation with reference to metformin (500 mg/kg) was assessed by monitoring various biochemical parameters at 10 day intervals during the course of therapy and at the end of 30 days S. maxima administration. Results: Significant (P<0.001) reductions in blood glucose, lipid profile (triglycerides, cholesterol and LDL, VLDL) and liver function markers (SGPT and SGOT) were recorded along with elevated level of HDL-C at the end of 30 days therapy of 5 or 10 per cent S. maxima aquous extract. Co-administration of S. maxima extract (5 or 10% aqueous) with 10 per cent fructose solution offered a significant protection against fructose induced metabolic abnormalities in Wistar rats. Interpretation & Conclusions: The present findings showed that S. maxima exhibited anti-hyperglycaemic, anti-hyperlipidaemic and hepatoprotective activity in rats fed with fructose. Further studies are needed to understand the mechanisms.

Simvastatin-induced cardiac autonomic control improvement in fructose-fed female rats

OBJECTIVE: Because autonomic dysfunction has been found to lead to cardiometabolic disorders and because studies have reported that simvastatin treatment has neuroprotective effects, the objective of the present study was to investigate the effects of simvastatin treatment on cardiovascular and autonomic changes in fructose-fed female rats. METHODS: Female Wistar rats were divided into three groups: controls (n=8), fructose (n=8), and fructose+ simvastatin (n=8). Fructose overload was induced by supplementing the drinking water with fructose (100 mg/L, 18 wks). Simvastatin treatment (5 mg/kg/day for 2 wks) was performed by gavage. The arterial pressure was recorded using a data acquisition system. Autonomic control was evaluated by pharmacological blockade. RESULTS: Fructose overload induced an increase in the fasting blood glucose and triglyceride levels and insulin resistance. The constant rate of glucose disappearance during the insulin intolerance test was reduced in the fructose group (3.4+ 0.32 percent/min) relative to that in the control group (4.4+ 0.29 percent/min). Fructose+simvastatin rats exhibited increased insulin sensitivity (5.4+0.66 percent/min). The fructose and fructose+simvastatin groups demonstrated an increase in the mean arterial pressure compared with controls rats (fructose: 124+2 mmHg and fructose+simvastatin: 126 + 3 mmHg vs. controls: 112 + 2 mmHg). The sympathetic effect was enhanced in the fructose group (73 + 7 bpm) compared with that in the control (48 + 7 bpm) and fructose+simvastatin groups (31+8 bpm). The vagal effect was increased in fructose+simvastatin animals (84 + 7 bpm) compared with that in control (49 + 9 bpm) and fructose animals (46+5 bpm). CONCLUSION: Simvastatin treatment improved insulin sensitivity and cardiac autonomic control in an experimental model of metabolic syndrome in female rats. These effects were independent of the improvements in the classical plasma lipid profile and of reductions in arterial pressure. These results support the hypothesis that statins reduce the cardiometabolic risk in females with metabolic syndrome.

Insulin sensitizing actions of fenugreek seed polyphenols, quercetin & metformin in a rat model.

Background & objectives: Plant polyphenols have been known to exert anti-diabetic action and promote insulin action. The present study was carried out to compare the effects of administration of fenugreek seed polyphenolic extract (FPEt), quercetin and metformin (a positive control) in an acquired model of insulin resistance (IR). Methods: Adult male Wistar rats divided into seven groups (n=12). IR was induced in groups (groups 2, 3, 4 and 5) by feeding a high fructose diet (FRU) (60 g/100 g diet) for 60 days. From day 16, FRU rats were administered either FPEt (200 mg/kg bw) (group 3), quercetin (50mg/kg bw) (group 4) or metformin (50 mg/kg bw) (group 5) for the next 45 days. Group 1 served as normal control while groups 6 and 7 served as FPEt and quercetin controls respectively. Oral glucose tolerance test (OGTT) was done on day 59 to assess glucose tolerance. At the end of 60 days, the levels of glucose, insulin, triglycerides (TG) and free fatty acids (FFA) were measured in the blood and the activities of insulin-inducible and suppressible enzymes in cytosolic and mitochondrial fractions of liver and skeletal muscle. The extent of tyrosine phosphorylation of proteins in response to insulin was determined by assaying protein tyrosine kinase (PTK) and protein tyrosine phosphatase (PTP) in liver. Results: Fructose caused increased levels of glucose, insulin, TG and FFA, alterations in insulin sensitivity indices, enzyme activities and reduced glycogen content. Higher PTP activity and lower PTK activity suggest reduced tyrosine phosphorylation status. Administration of FPEt or quercetin improved insulin sensitivity and tyrosine phosphorylation in fructose-fed animals and the effect was comparable with that of metformin. Interpretation & conclusions: Our findings indicated that FPEt and quercetin improved insulin signaling and sensitivity and thereby promoted the cellular actions of insulin in this model.

Evaluation of the chronic complications of diabetes in a high fructose diet in rats.

The increasing prevalence of type 2 diabetes is associated with increasing health costs, especially for the treatment of cardiovascular disease. The development of new treatment modalities requires animal models that mimic the range of pathophysiological changes seen in diabetic humans. Dietary fructose intake has been linked to the increase in insulin resistance as part of the metabolic syndrome; fructose-fed rats develop type 2 diabetes. This study has characterized the cardiovascular changes in young adult male Wistar rats fed a 61% fructose diet for 16 weeks. Our results extend the reported changes of hypertension, lipid abnormalities, impaired glucose tolerance and impaired oxidative defense to include ventricular dilatation with hypertrophy and decreased contractile function, together with increased inflammatory cell infiltration into the ventricular myocardium, resulting in excessive collagen deposition and an increased stiffness of the left ventricle. However, endothelial dysfunction, tactile allodynia as a symptom of peripheral neuropathy and retinopathy are not present in these rats, in contrast to the streptozotocin-induced model of type 1 diabetes. Thus, fructose feeding mimics many, but not all, of the symptoms of type 2 diabetes in humans.

Papel de la monoterapia con nuevos fármacos antiepilépticos en el tratamiento de la epilepsia infantil / Role of monotherapy with new antiepileptic drugs in the treatment of childhood epilepsy

En este trabajo se revisa la información actual sobre el uso de los nuevos fármacos antiepilépticos (FAEs) en monoterapia en niños, resaltando nuestra experiencia personal. Específicamente, se incluyen los siguientes FAEs: lamotrigina (Lamictal®), topiramato (Topamax®), zonisamida (Zonegran®), levetiracetam (Keppra®), y oxcarbacepina (Trileptal®). Todos estos FAEs tienen un amplio espectro de acción en el tratamiento de crisis epilépticas parciales y generalizadas, excepto la oxcarbacepina, que es eficaz exclusivamente en crisis parciales. No está claro si la monoterapia con estos FAEs, en comparación con los FAEs clásicos (fenobarbital, fenitoína, carbamacepina, valproato sódico), proporciona una mayor eficacia y/o causa menos efectos secundarios y, si por lo tanto, mejora significativamente la calidad de vida de los niños con epilepsia. Se necesitan más estudios para poder contestar estas preguntas.

In this paper we review the current information regarding the use of new antiepileptic drugs (AEDs) used as monotherapy in children. We specifically include the following AEDs: lamotrigine (Lamictal®), topiramate (Topamax®), zonisamide (Zonegran®), levetiracetam (Keppra®), and oxcarbazepine (Trileptal®). All of these AEDs have a broad spectrum of action in the treatment of partial and generalized seizures, except Oxcarbazepine, which is effective only in partial seizures. It is unclear whether or not monotherapy with the new AEDs offers higher efficacy and/or lower side effects compared to classic AEDs (phenobarbital, phenytoin, carbamazepine, or valproate) thereby significantly improving the quality of life in children with epilepsy. More studies are needed to answer these questions.

[Effects of topiramate in the prevention of drug resistant migraine headache]

Migraine is the most common cause of headache. The aim of the present study was to evaluate the effects of topiramate [TPM] in the prevention of drug-resistant migraine headache. This is a double-blind clinical trial conducted on 70 patients between ages 15 to 45 years referred to the Bu Ali Sina Hospital in Sari with a history of migraine attacks based on International Headache Society criteria for a period of more than one years with a minimum incidence of 1 to 6 attacks per month. The drug rate performance was assessed by response rate to treatment, mean changes in the number and severity of migraine attacks compare with the placebo group for 3 months. Collected data were analyzed using analysis of variance [ANOVA], Newman-Keuls and Spearman's Coefficient Rank Correlation as the post hoc tests. GRAPHPAD software was used for analysis of the data. 66 of 70 patients completed the study. The mean age of the patients was 30.33 +/- 7.9 years. A significant reduction in the severity and frequency of migraine attacks was seen in all months [P<0.0001] for topiramate treated group in compare to placebo group. Responder rate for patients treated with TPM was significantly higher than placebo group [64.6%, P<0.0001] in the 3 rd month of the treatment side effects of treatment were transient and well tolerated. Low dose of TPM showed significant efficacy in prevention of migraine attacks within the first, second, and third month of treatment. Low dose of TPM seems to be a good therapeutic option for the patients with refractory migraine

Bilateral acute onset myopia and angle closure glaucoma after oral topiramate: a case report.

OBJECTIVE: Describe bilateral acute onset myopia and angle-closure glaucoma as ocular adverse effects of topiramate. CASE REPORT: A 23 year-old woman developed bilateral severe blurred vision seven days after initiating therapy with topiramate. Her visual acuity was counting fingers in both eyes. Intraocular pressures were 33 mmHg and 32 mmHg in the right and left eyes, respectively, with conjunctival chemosis, corneal edema, shallow anterior chambers, and closed angles. Her refraction was -7.50 diopters in both eyes. The symptoms and clinical findings resolved completely upon discontinuation of topiramate and, administration of antiglaucoma drugs. CONCLUSION: Topiramate use can result in acute bilateral angle-closure glaucoma and myopia, which are usually reversible upon cessation of the drug. Visual outcome is usually good and the episode resolves within a few weeks. Thus, it is important for clinicians to recognize these conditions and educate patients about these serious adverse effects when prescribing topiramate.

Topiramate induced histopathological changes in placenta of rats.

Effect of topiramate, an antiepileptic drug, on the development of conceptus and its safety during pregnancy has been investigated in experimental rats. Rats were treated with topiramate dissolved in tap water in the doses of 40. 100 and 200 mg/kg body weight from day 9 to 12 of gestation through oral route. Fetuses along with placenta were collected for examination on day 21 of gestation after sacrificing the pregnant rats with deep ether anaesthesia. The placenta showed neither significant reduction in weight as compared to the controls nor any overt anomaly. However. on microscopic examination all treated groups showed similar structural changes which increased in severity with increase in the dose of the drug. The deciduas basalis showed thickening, heamorrhage and increased fibrinoid deposit. Disproportionately increased frequency of vacuolated giant cells was observed in the basal zone whereas frequently broken trichorial membrane. homogenous labyrinthine septa and increased fetal mesenchyme were observed in the placental barrier. The results suggested that topiramate induced dose dependent deleterious changes in the structure of placenta, therefore it should be used with caution during pregnancy.

Parasympathetic dysfunction is associated with insulin resistance in fructose-fed female rats

The objective of the present study was to identify metabolic, cardiovascular and autonomic changes induced by fructose overload administered in the drinking water of rats for 8 weeks. Female Wistar rats (200-220 g) were divided into 2 groups: control (N = 8) and fructose-fed rats (N = 5; 100 mg/L fructose in drinking water for 8 weeks). The autonomic control of heart rate was evaluated by pharmacological blockade using atropine (3 mg/kg) and propranolol (4 mg/kg). The animals were submitted to an intravenous insulin tolerance test (ITT) and to blood glucose measurement. The fructose overload induced a significant increase in body weight (~10 percent) and in fasting glycemia (~28 percent). The rate constant of glucose disappearance (KITT) during ITT was lower in fructose-fed rats (3.25 ± 0.7 percent/min) compared with controls (4.95 ± 0.3 percent/min, P < 0.05) indicating insulin resistance. The fructose-fed group presented increased arterial pressure compared to controls (122 ± 3 vs 108 ± 1 mmHg, P < 0.05) and a reduction in vagal tonus (31 ± 9 vs 55 ± 5 bpm in controls, P < 0.05). No changes in sympathetic tonus were observed. A positive correlation, tested by the Pearson correlation, was demonstrable between cardiac vagal tonus and KITT (r = 0.8, P = 0.02). These data provided new information regarding the role of parasympathetic dysfunction associated with insulin resistance in the development of early metabolic and cardiovascular alterations induced by a high fructose diet.

Treatment of trigeminal neuralgia with low doses of topiramate

Topiramate was administered to eight patients with classical trigeminal neuralgia with or without previous symptomatic therapy with other antiepileptic drugs. The topiramate doses ranged from 50 to 100 mg a day, according to the clinical response and the reported side effects. Three patients had complete symptoms remission, three reported moderate improvement, and the treatment was not effective in two. The most frequently registered side effects were dizziness, somnolence and weight loss. Topiramate can be considered an alternative treatment for patients with trigeminal neuralgia.

Oito pacientes com neuralgia do trigêmeo, com ou sem tratamentos prévios com anticonvulsivantes, foram submetidos a tratamento com topiramato. As doses de topiramato variaram de 50 a 100 mg ao dia, de acordo com a resposta clínica e com os efeitos colaterais relatados. Três pacientes obtiveram remissão completa, três relataram melhora parcial e o tratamento com topiramato foi ineficaz em dois pacientes. Os efeitos colaterais mais frequentemente citados foram tontura, sonolência e perda de peso. O topiramato pode ser considerado uma alternativa potencialmente eficaz para o tratamento de pacientes com neuralgia do trigêmeo.

Participación del hipotálamo en la regulación de la presión arterial en un modelo de hipertensión e insulinorresistencia / Role of the hypothalamus in blood pressure regulation in a model of hypertension and insulin resistance

Objetivo: Evaluar el papel del área hipotalámica anterior en la regulación de la presión arterial en un modelo en ratas de hipertensión arterial (HTA) e insulinorresistencia. Material y métodos: Se utilizaron ratas Sprague-Dawley macho (n = 72) que fueron divididas en dos grupos: F,fructosa (10 por ciento p/v por 6 semanas) y C, grupo control. Se canuló la arteria carótida izquierda para la medición de la presión arterial media (PAM) y la frecuencia cardíaca (FC). Se colocó una sonda de microdiálisis en el área hipotalámica anterior (AHA) para la perfusión de yohimbina (10 y 100 µg/ml) o de clonidina (100 y 300 µg/ml), antagonista y agonista α2-adrenérgicos, respectivamente, y se evaluaron los cambios hemodinámicos. Resultados: Los animales del grupo F presentaron niveles mayores de presión arterial sistólica que los del grupo C (F: 131 ± 3 mm Hg versus C: 112 ± 4 mm Hg; p < 0,05). La perfusión intrahipotalámica de yohimbina indujo un incremento en la PAM en C, en tanto que no modificó los valores en F. No se encontraron cambios en la FC en ninguno de los grupos. La clonidina en dosis de 100 µg/ml indujo una disminución de la PAM sólo en F, mientras que en dosis de300 µg/ml la disminuyó en ambos grupos y fue mayor en F que en C. Sólo la clonidina en dosis de 300 µg/ml disminuyó la FC en el grupo F, sin modificar los valores en C. Conclusiones: Existiría un tono α2-adrenérgico menor en el AHA de las ratas F, que podría relacionarse con el incremento de la presión arterial presente en este grupo. Por otra parte, la respuesta exacerbada a la clonidina en F evidenciaría la existencia de una supersensibilidad de receptores adrenérgicos hipotalámicos, posiblemente como consecuencia de niveles extracelulares reducidos de noradrenalina en el AHA en este modelo de HTA e insulinorresistencia.

Opposite lipemic response of Wistar rats and C57BL/6 mice to dietary glucose or fructose supplementation

The metabolic effects of carbohydrate supplementation in mice have not been extensively studied. In rats, glucose- and fructose-rich diets induce hypertriacylglycerolemia. In the present study, we compared the metabolic responses to two monosaccharide supplementations in two murine models. Adult male Wistar rats (N = 80) and C57BL/6 mice (N = 60), after 3 weeks on a standardized diet, were submitted to dietary supplementation by gavage with glucose (G) or fructose (F) solutions (500 g/L), 8 g/kg body weight for 21 days. Glycemia was significantly higher in rats after fructose treatment (F: 7.9 vs 9.3 mM) and in mice (G: 6.5 vs 10 and F: 6.6 vs 8.9 mM) after both carbohydrate treatments. Triacylglycerolemia increased significantly 1.5 times in rats after G or F supplementation. Total cholesterol did not change with G treatment in rats, but did decrease after F supplementation (1.5 vs 1.4 mM, P < 0.05). Both supplementations in rats induced insulin resistance, as suggested by the higher Homeostasis Model Assessment Index. In contrast, mice showed significant decreases in triacylglycerol (G: 1.8 vs 1.4 and F: 1.9 vs 1.4 mM, P < 0.01) and total cholesterol levels (G and F: 2.7 vs 2.5 mM, P < 0.05) after both monosaccharide supplementations. Wistar rats and C57BL/6 mice, although belonging to the same family (Muridae), presented opposite responses to glucose and fructose supplementation regarding serum triacylglycerol, free fatty acids, and insulin levels after monosaccharide treatment. Thus, while Wistar rats developed features of plurimetabolic syndrome, C57BL/6 mice presented changes in serum biochemical profile considered to be healthier for the cardiovascular system.