Melatonin ameliorates brain oxidative stress and upregulates senescence marker protein-30 and osteopontin in a rat model of vascular dementia

The aim of this study was to investigate the effect of melatonin on oxidative stress and senescence marker protein-30 (SMP30) as well as osteopontin (OPN) expression in the hippocampus of rats subjected to vascular dementia (VD). A total of 72 male rats were divided into six groups (n = 12 each) as follows: (i) untreated control (CON), (ii) sham-operated group, (iii) sham-operated + melatonin, (iv) rats exposed to VD induced by permanent bilateral occlusion of the common carotid arteries (BCCAO) leading to chronic cerebral hypoperfusion, (v) rats exposed to VD + melatonin, and (vi) rats exposed to VD + donepezil (DON). At the end of experiment, the hippocampal levels of acetylcholine (ACh), norepinephrine (NE), and dopamine (Dop) were measured. Expression of OPN was determined using immunohistochemistry, and SMP30 expression was determined using real-time PCR in the hippocampus. Hippocampal thiobarbituric acid reactive substances (TBARS) and total antioxidant capacity (TAC) were evaluated. The BCCAO group showed significantly decreased TAC (p < 0.05) and significantly increased in TBARS levels compared with the CON group. In addition, BCCAO significantly decreased (p < 0.05) the expression of both OPN and SMP30 and the levels of ACh, NE, and Dop in the hippocampus compared with CON treatment. Treatment with melatonin significantly increased OPN and SMP30 expression and ACh, NE, and Dop levels in the hippocampus with amelioration of the oxidative stress compared with BCCAO rats. Melatonin might produce a neuroprotective effect through its antioxidant action and by increasing the expression of SMP30 and OPN that is not comparable with that of DON

Effects of low dose of aliskiren on isoproterenol-induced acute myocardial infarction in rats

This study examined the effects of aliskiren (Ali) (direct renin inhibitor) on serum cardiac enzymes (LDH and CK-MB), electrocardiography (ECG) changes, myocardial oxidative stress markers (MDA, CAT, and GSH) and the expression of Bcl2, HO-1, and Nrf2 genes in isoproterenol (ISO)-induced myocardial infarction (MI). A total of 40 male albino rats were allocated into four groups, (1) normal control (NC) group, (2) Ali group (rats received Ali at 10 mg/kg/day p.o. for 5 days), (3) ISO group (rats received ISO 150 mg/kg i.p. for two consecutive days at 24 h intervals), and (4) Ali + ISO group (rats received ISO + Ali at 10 mg/kg/day p.o. for 5 days from the 2nd dose of ISO). ISO group showed significant rise in serum cardiac enzymes (CK-MB and LDH), myocardial damage scores, myocardial MDA, HO-1, myocardial Nrf2 expression with significant reduction in myocardial antioxidants (CAT and GSH), and Bcl2 expression compared to the normal group (p < 0.05). ECG showed ST segment elevation, prolonged QT interval and QRS complex, and increased heart rate in ISO group. Co-administration of Ali and ISO caused significant increase in cardiac enzymes and morphology with increase in MDA, serum K, and creatinine with significant decrease in Bcl2, HO-1, and Nrf2 without significant changes in ECG parameters compared to ISO group. We concluded that low dose of Ali seems to exacerbate the myocardial injury in ISO-MI, which might be due to the enhanced oxidative stress and apoptosis

Elevated basal cytosolic calcium of endothelial cells influences the post-surgical outcome in diabetic CTS

Background Type 2 diabetes mellitus (T2DM)-induced neuropathy and ischemia-reperfusion post-surgery prolong carpal tunnel syndrome (CTS) pathology, but the effect of T2DM on the prognostic outcome of carpal tunnel (CT) release surgery needs to be investigated. Materials and methods A total of 64 individuals with CTS underwent CT release surgery. HbA1c levels identified their diabetic status. The individual prognostic outcomes were measured by nerve conduction velocity (NCV), amplitude, and latency. Measurement of [Ca2+]c and reactive oxygen species (ROS) from isolated endothelial cells (ECs) revealed the oxidative burden of the normal and diabetic CTS phenotypes. Results CTS individuals with HbA1c > 7 showed decreased NCV (≈22 m/s) and amplitude (≈4.2 mV) with increased latency (≈6 ms), compared to groups with HbA1c ≤ 7. Further to CT release surgery, the reversal of the nerve conduction to normalcy was greatly influenced by the diabetic profile of the individuals. Our results showed elevated basal [Ca2+]c and corresponding high cytosolic ROS in the ECs isolated from individuals with HbA1c > 7 compared to the diabetic and healthy control groups. Conclusion The individuals with diabetic index showed suboptimal neuronal performance pre- and post-CT release surgery. Oxidative stress mediated by high [Ca2+]c and ROS of ECs dissipates to adjoining cells worsening the pathology of the untreated CTS

Derangement of hemopoiesis and hematological indices in Khat (Catha edulis) - treated rats

The purpose of this study was to identify the sub-acute toxic effects of Khat (Catha edulis) on hemopoiesis and hematological indices of white albino rats. Two groups, each of 10 rats, were used. In the experimental group, a hydro-ethanol extract of C. edulis was administered orally to rats, daily, in single doses of 500 mg/kg body weight, for for weeks. The control group received equivalent amounts of normal saline. Our results show, for the first time, that oral administration of C. edulis hydro-ethanol extract caused significant derangement in hemopoiesis and in gross hematological indices in rats, characterized by macrocytic anemia and leucopenia. Our data show statistically significant decreases in total leukocytes count (TLC) in which, hemoglobin concentration (Hb. conc.), packed cell volume (PCV), and red cell count (RCC), accompanied by significant increases in mean cell volume (MCV), red blood cell distribution width (RDW) and platelets count with no change in mean hemoglobin concentration (MHC). In peripheral blood smears (PBS) of treated rats, there were evidences of dyserythropoiesis- impaired hemoglobinization, macrocytosis, poikilocytosis and anisocytosis, and dysgranulopoiesis- giant forms, hypersegmented neutrophils and bizarre nuclear shapes. In conclusion, our results indicate that oral administration of a hydro-ethanol extract of C. edulis adversely affected blood cell formation and induced macrocytic anemia and leukopenia in rats. However, the exact mechanisms of these hematological changes produced by Khat are still in need for further studies.Keywords:Catha edulis, hemopoiesis, anemia, leukopenia, ratsAfrican Journal of Biotechnology, Vol. 13(2), pp. 349-355, 8 January, 201

Natural Hypoxia is Not a Limiting Factor in Evaluating the Novel Arylidene Derivative MLT-401 Against an In Vitro Colorectal Cancer Model

Background/Aims: Cancer cells in vivo develop resistance to many anti-tumor drugs. One known factor to influence such drug resistance is hypoxia, which is an important component of the tumor microenvironment. Standard cancer lines mostly do not exhibit a cellular hypoxic microenvironment and there is a paucity of information on the efficacy of lead molecules in both cellular- and environment-induced hypoxic conditions. Therefore, in the present study, we have evaluated the efficacy of the arylidene derivative MLT-401, a lead molecule showing activity against colorectal cancer model using the HCT 116 cell line and CCD-80-C control cells in normoxic and natural (marginal) hypoxic conditions, which is usually observed in high-altitude regions. Methods: The efficacy of MLT-401 on HCT 116 and CCD-80-C cells were tested in both normoxia and marginal hypoxia conditions. MTT assay was used to evaluate cell proliferation, Annexin V binding assay for apoptotic cell quantification and PI staining for cell cycle were done by flow cytometry. Induction of pro-apoptotic marker BAX and anti-apoptotic Bcl-2 were assessed by western blot. Bcl-2/BAX ratio was calculated based on protein expression by western blotting and bands were quantified by Image J software. Results: Analysis of cell proliferation showed an average 10-fold reduction in the inhibition of HCT 116 cells in hypoxic conditions with approximately 500 nM MLT-401, while there was no significant change noted in marginal hypoxic conditions. A proportionate increase in the number of apoptotic cells and large M4 fraction of 10.5% and 26.7% of HCT116 against 6.3% of control cells in cell cycle assessment with MLT-401 concentrations ranging from 250 to 500 nM respectively clearly demonstrated anti-cancer activity. A Bcl-2/BAX ratio of &#x3c; 1 showed that the induction of apoptosis was the gross mechanism underlying the inhibition of HCT 116 cells by MLT-401. Conclusion: Collectively, these results show MLT-401 as an effective anti-colorectal cancer lead molecule irrespective of normoxia or natural hypoxia