RESUMEN
Angiotensin II [Ang II] has an important role on cerebral microcirculation; however, its direct roles in terms of ischemic brain edema need to be clarified. This study evaluated the role of central Ang II by using candesartan, as an ATI receptor blocker, in the brain edema formation and blood-brain barrier [BBB] disruption caused by ischemia/reperfusion [I/R] injuries in rat. Rats were exposed to 60-min middle cerebral artery [MCA] occlusion. Vehicle and non-hypotensive doses of candesartan [0.1 mg/kg] were administered one hour before ischemia. Neurological dysfunction scoring was evaluated following 24 h of reperfusion. Animals were then decapitated under deep anesthesia for the assessments of cerebral infarct size, edema formation, and BBB permeability. The outcomes of 24 h reperfusion after 60-min MCA occlusion were severe neurological disability, massive BBB disruption [Evans blue extravasation = 12.5 +/- 1.94 microg/g tissue], 4.02% edema, and cerebral infarction [317 + 21 mm[3]]. Candesartan at a dose of 0.1 mg/kg, without changing arterial blood pressure, improved neurological dysfunction scoring together with significant reductions in BBB disruption [54.9%], edema [59.2%], and cerebral infarction [54.9%]. Inactivation of central ATI receptors, if not accompanied with arterial hypotension, protected cerebral micro-vasculatures from damaging effects of acute stroke
RESUMEN
Background: The cardiac effects simultaneously occurring during experimental hypertension and diabetes have rarely been investigated. This study aimed at examining the effects of shortterm renovascular hypertension and type 2 diabetes on cardiac functions
Methods: Five groups [7 each] of male Sprague-Dawley rats, including a control group, a diabetes [induced by Streptozocin and Nicotinamide] group, a renovascular hypertensive [induced by placing Plexiglas clips on the left renal arteries] group, a sham group, and a simultaneously hypertensive-diabetic group, were used. The animals' hearts were used for isolated heart studies, and the indices of cardiac functions and coronary effluent creatine kinase MB were measured. The results were analyzed using One-way Analysis of Variance, followed by the Duncan Multiple Range test
Results: The diabetic group had a significantly lower rate of rise [-29.5%] and decrease [-36.18%] in ventricular pressure, left ventricular developed pressure [-28.8%], and rate pressure product [-35%], and significantly higher creatine kinase MB [+166%] and infarct size [+36.2%] than those of the control group. The hypertensive group had a significantly higher rate of rise [+12.17%] and decrease [+16.2%] in ventricular pressure, left ventricular developed pressure [+16%], and rate pressure product [+24%], and significantly lower creatine kinase MB [-30%] and infarct size [-27%] than those of the sham group. Simultaneously, the diabetic and hypertensive rats had a significantly higher rate of rise [+32%] and decrease [+30.2%] in ventricular pressure, left ventricular developed pressure [+17.2%], and rate pressure product [+22.2%], and significantly lower creatine kinase MB [-24%] and infarct size [-16.2%] than those of the diabetic group
Conclusion: The findings indicated that the simultaneity of hypertension with type 2 diabetes attenuated diabetes-induced cardiac impairment
RESUMEN
Background: Pomegranate seed oil and its main constituent, punicic acid, have been shown to decrease plasma glucose and have antioxidant activity. The objective of the present study was to examine the effects of pomegranate seed oil on rats with type 2 diabetes mellitus
Method: Six groups [n=8 each] of male Sprague-Dawley rats, comprising a control, a diabetic [induced by Streptozocin and Nicotinamide] receiving water as vehicle, a diabetic receiving pomegranate seed oil [200 mg/kg/day], a diabetic receiving pomegranate seed oil [600 mg/kg/day], a diabetic receiving soybean oil [200 mg/kg/day], and a diabetic receiving soybean oil [600 mg/kg/day], were used. After 28 days of receiving vehicle or oils, blood glucose, serum levels of insulin, malondialdehyde, glutathione peroxidase, and lipid profile were determined
Results: The diabetic rats had significantly higher levels of blood glucose, serum triglyceride, low-density lipoprotein cholesterol, total cholesterol, and malondialdehyde and lower levels of serum insulin and glutathione peroxidase. Rats treated with pomegranate seed oil had significantly higher levels of serum insulin and glutathione peroxidase activity, and there were no statistically significant differences in terms of blood glucose between them and the diabetic control group
Conclusion: The findings of the present study suggest that pomegranate seed oil improved insulin secretion without changing fasting blood glucose
RESUMEN
Background: B cell CLL/lymphoma 2 protein, bcl-2, is an important anti-apoptotic factor that has been implicated in lithium's neuroprotective effect. However, most studies have focused on assessing the effects of lithium in neurons, ignoring examination of bcl-2 in astrocytes, which also influence neuronal survival and are affected in bipolar disorder. The aim of this study was to evaluate whether chronic lithium treatment also elevates bcl-2 expression in astrocytes compared with neuronal and mixed neuron-astrocyte cultures
Methods: Rat primary astrocyte, neuronal, and mixed neuronastrocyte cultures were prepared from the cerebral cortices of 18-day embryos. The cell cultures were treated with lithium [1 mM] or vehicle for 24 h or 7 days. Thereafter, bcl-2 mRNA and protein levels were determined by RT-PCR and ELISA, respectively
Results: Chronic, but not acute, lithium treatment significantly increased bcl-2 protein levels in the astrocyte cultures compared with the vehicle-treated cultures. While lithium treatment increased bcl-2 protein levels in both neuronal and mixed neuron-astrocyte cultures, the elevations fell short of statistical significance compared with the respective vehicle-treated cultures. However, neither acute nor chronic lithium treatment affected bcl-2 mRNA levels in any of the three cell types studied
Conclusion: Increased bcl-2 levels in rat primary astrocyte cultures following chronic lithium treatment suggest astrocytes are also a target of lithium's action. In light of the evidence showing decreased numbers of glial cells in the post-mortem brain of patients bipolar disorder with and increased glial numbers following lithium treatment, the findings of this study indicate that lithium's action on astrocytes may account, at least in part, for its therapeutic effects in bipolar disorder