887 resultados para rats inbred Lewis


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objective: To study the antihyperlipidemic effect of Cedrus deodara (C. deodara) against monosodium glutamate (MSG) induced obesity in neonatal rats. Materials and Methods: The studies were carried out on newborn neonatal rats and were injected intraperitoneally with 2 mg/g of MSG on the 2(nd) and 4(th) postnatal days and 4 mg/g on 6(th), 8(th) and 10(th) postnatal days. Ethanolic extract (EE) and acetone extract (AE) of C. deodara was administered in a dose of 100 and 200 mg/kg, p.o./day at the age of 65 days. On day 60 of treatment, body weight, locomotor activity, body temperature, and various biochemical parameters like serum glucose, total cholesterol, triglyceride, and organs weights were recorded. Results: There was a significant reduction in body weight, organs and increased body temperature, locomotor activity after treatment with extracts. C. deodara decreased serum glucose, total cholesterol and triglyceride, low density lipoprotein (LDL) and very low density lipoprotein (VLDL) levels and increased high density lipoprotein (HDL) significantly has compared to MSG-control rats. Conclusion: C. deodara extracts exhibited antihyperlipidemic effect and it possesses anti-obesity properties in MSG induced obese rats.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objective: This study was undertaken to evaluate the neuroprotective activity of Wedelia calendulacea against cerebral ischemia/reperfusion induced oxidative stress in the rats. Materials and Methods: The global cerebral ischemia was induced in male albino Wistar rats by occluding the bilateral carotid arteries for 30 min followed by 1 h and 4 h reperfusion. At various times of reperfusion, the histopathological changes and the levels of malondialdehyde (MDA), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-s-transferase (GST), and hydrogen peroxide (H(2)O(2)) activity and brain water content were measured. Results: The ischemic changes were preceded by increase in concentration of MDA, hydrogen peroxide and followed by decreased GPx, GR, and GST activity. Treatment with W. calendulacea significantly attenuated ischemia-induced oxidative stress. W. calendulacea administration markedly reversed and restored to near normal level in the groups pre-treated with methanolic extract (250 and 500 mg/kg, given orally in single and double dose/day for 10 days) in dose-dependent way. Similarly, W. calendulacea reversed the brain water content in the ischemia reperfusion animals. The neurodegenaration also conformed by the histopathological changes in the cerebral-ischemic animals. Conclusion: The findings from the present investigation reveal that W. calendulacea protects neurons from global cerebral-ischemic injury in rat by attenuating oxidative stress.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The present study was to investigate the effect of W. calendulacea on ischemia and reperfusion-induced cerebral injury. Cerebral ischemia was induced by occluding right and left common carotid arteries (global cerebral ischemia) for 30 min followed by reperfusion for 1 h and 4 h individually. Various biochemical alterations, produced subsequent to the application of bilateral carotid artery occlusion (BCAO) followed by reperfusion viz. increase in lipid peroxidation (LPO), hydrogen peroxide (H(2)O(2)), and decrease in reduced glutathione (GSH), catalase (CAT) and superoxide dismutase (SOD), level in the brain tissue, Western blot analysis (Cu-Zn-SOD and CAT) and assessment of cerebral infarct size were measured. All those enzymes are markedly reversed and restored to near normal level in the groups pre-treated with W. calendulacea (250 and 500 mg/kg given orally in single and double dose/day for 10 days) in dose-dependent way. The effect of W. calendulacea had increased significantly the protein expression of copper/zinc superoxide dismutase (Cu-Zn-SOD) and CAT in cerebral ischemia. W. claendulacea was markedly decrease cerebral infarct damages but results are not statistically significant. It can be concluded that W. calendulacea possesses a neuroprotective activity against cerebral ischemia in rat.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In recent times, (thio)urea derivatives have become synonymous with hydrogen bonding owing to their extensive applicability as small molecule organocatalysts. In this paper, another activation mode by thiourea derivatives, namely via Lewis base catalysis, is disclosed for the NBS-mediated oxidation of alcohols. The mild reaction conditions employed here is suitable for chemoselective oxidation of secondary alcohol in the presence of primary alcohol.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

To study the efficacy of ethanolic extract of B. monosperma bark in cafeteria and atherogenic diet fed rats and monosodium glutamate (MSG) obese rats, different doses (200, 400 and 800 mg/kg) of ethanolic extract of B. monosperma bark showed dose dependent decrease in body weight, daily food intake, glucose, lipids, internal organs' weight and fat pad weight in cafeteria and atherogenic diet fed rats and monosodium glutamate obese rats. The results suggested that B. monosperma has significant anti-obese activity.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Optically active Lewis acids and Lewis pairs were synthesized and characterized by multinuclear NMR, UV/Vis spectroscopy and elemental analysis. Optical rotation measurements were carried out and the absolute configuration of the new chiral molecules confirmed by single crystal X-ray diffraction.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Currently beta-adrenergic receptor blockers are considered to be potential drugs under investigation for preventive or therapeutic effect in osteoporosis. However, there is no published data showing the comparative study of beta-blockers with well accepted agents for the treatment of osteoporosis. To address this question, we compared the effects of propranolol with well accepted treatments like zoledronic acid and alfacalcidol in an animal model of postmenopausal osteoporosis. Five days after ovariectomy, 36 ovariectomized (OVX) rats were divided into 6 equal groups, randomized to treatments zoledronic acid (100 mu g/kg, intravenous single dose); alfacalcidol (0.5 mu g/kg, oral gauge daily); propranolol (0.1 mg/kg, subcutaneously 5 days per week) for 12 weeks. Untreated OVX and sham OVX were used as controls. At the end of treatment serum calcium and alkaline phosphatase were assayed. Femurs were removed and tested for bone density, bone porosity, bone mechanical properties and trabecular micro-architecture. Propranolol showed a significant decrease in alkaline phosphatase levels and bone porosity in comparison to OVX control. Moreover, propranolol significantly improved bone density, bone mechanical properties and inhibited the deterioration of trabecular microarchitecture when compared with OVX control. The osteoprotective effect of propranolol was comparable with zoledronic acid and alfacalcidol. Based on this comparative study, the results strongly suggest that propranolol can be a candidate therapeutic drug for the management of postmenopausal osteoporosis.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

An enantioselective vinylogous umpolung addition of deconjugated butenolides to allenoates has been developed for the first time with the help of synergistic combination of an achiral phosphine and a chiral squaramide, and represents the first example of a catalytic enantioselective C gamma-C gamma bond formation between two different carbonyl partners.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: This study was performed to understand the possible therapeutic activity of Terminalia paniculata ethanolic extract (TPEE) on non alcoholic fatty liver in rats fed with high fat diet. Methods: Thirty six SD rats were divided into 6 groups (n = 6): Normal control (NC), high fat diet (HFD), remaining four groups were fed on HFD along with different doses of TPEE (100,150 and 200 mg/kg b.wt) or orlistat, for ten weeks. Liver tissue was homogenized and analyzed for lipid profiles, activities of superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) content. Further, the expression levels of FAS and AMPK-1 alpha were also studied in addition to histopathology examination of liver tissue in all the groups. Results: HFD significantly increased hepatic liver total cholesterol (TC), triglycerides (TG), free fatty acids (FFA) and MDA but decreased the activities of SOD and CAT which were subsequently reversed by supplementation with TPEE in a dose-dependent manner. In addition, TPEE administration significantly down regulated hepatic mRNA expression of FAS but up regulated AMPK-1 alpha compared to HFD alone fed group. Furthermore, western blot analysis of FAS has clearly demonstrated decreased expression of FAS in HFD + TPEE (200 mg/kg b. wt) treated group when compared to HFD group at protein level. Conclusions: Our biochemical studies on hepatic lipid profiles and antioxidant enzyme activities supported by histological and expression studies suggest a potential therapeutic role for TPEE in regulating obesity through FAS.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Insertion reactions of six-membered cyclopalladated N,N',N''-triarylguanidines, kappa(2)(C,N)Pd(mu-Br)](2) with various alkynes in CH2Cl2 under ambient conditions afforded diinserted eight-membered palladacycles, (kappa(2)(C,N):eta(2)(C=C)-PdBr] (1-11), in high yield (76-96%), while insertion reactions of six-membered cyclopalladated N,N',N''-triarylguanidines, kappa(2)(C,N)Pd(Lewis base)Br] (VI-XI), with various alkynes under the aforementioned conditions afforded monoinserted six-membered palladacycles, kappa(2)(C,N)-Pd(Lewis base)Br] (12-21), in high yield (81-91%) except for 14 (23%). The insertion reaction of VI with 2 equiv of dimethyl acetylenedicarboxylate (DMAD) and the insertion reaction of 12 with 1 equiv of DMAD in CH2Cl2 under ambient conditions resulted in the formation of a diinserted zwitterionic five-membered palladacycle, kappa(2)(C,C)Pd(2,6-lutidine)Br] (22), in 76% and 70% yields, respectively. Palladacycle 22 upon reaction with AgOTf in wet MeCN afforded the ionic palladacycle kappa(2)(C,C)Pd(2,6-lutidine)(H2O)]OTf] (23) in 78% yield. The ring size of the ``kappa(2)(C,N)Pd]'' unit in the structurally characterized diinserted palladacycles (1 center dot 2CH(2)Cl(2)center dot H2O, 2, 5, and 7), and monoinserted palladacycles (17, 18, and 20 center dot C7H8 H2O) is smaller than that anticipated for mono- and diinserted palladacycles, and this feature is mainly ascribed to the proclivity of III-XI to undergo ring contraction cum amine-imine tautomerization upon alkyne insertion. Palladacycle 22 represents the first diinserted product obtained in alkyne insertion reactions of kappa(2)(C,N)Pd(Lewis base)X] type palladarycles. The molecular structure of 22 center dot H2O determined by X-ray diffraction indicates that the positive charge on the guanidinium moiety is balanced by the negative charge on the palladium atom and thus represents the first structurally characterized zwitterionic palladacycle to be reported in alkyne insertion chemistry. Plausible mechanisms of formation of 12-21 and 22 have been outlined. The presence of more than one species in solution for some of the palladacycles in the series 1-7 and 12-21 was explained by invoking the C-N single-bond rotation of the CN3 unit of the guanidine moiety, while this process in conjunction with Pd-N(lutidine) bond rotation was invoked to explain the presence of four isomers of 15, as studied with the aid of variable-concentration H-1 NMR experiments carried out for 14 and 15.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We conducted the present study to investigate the therapeutic effects of the antiresorptive agent zoledronic acid (ZOL), alone and in combination with alfacalcidol (ALF), in a rat model of postmenopausal osteoporosis. Female Wistar rats were ovariectomized (OVX) or sham-operated at 3 months of age. Twelve weeks post surgery, rats were randomized into six groups: (1) sham + vehicle, (2) OVX + vehicle, (3) OVX + ZOL (100 mu g/kg, i.v. single dose), (4) OVX + ZOL (50 mu g/kg, i.v. single dose), (5) OVX + ALF (0.5 mu g/kg, oral gauge daily) and (6) OVX + ZOL (50 mu g/kg, i.v. single dose) + ALF (0.5 mu g/kg, oral gauge daily) for 12 weeks. After treatment, we evaluated the mechanical properties of the lumbar vertebra and femoral mid-shaft. Femurs were also tested for bone density, porosity and trabecular micro-architecture. Biochemical markers in serum and urine were also determined. With respect to improvement in the mechanical strength of the lumbar spine and the femoral mid-shaft, the combination treatment of ZOL and ALF was more effective than each administered as a monotherapy. Moreover, combination therapy using ZOL and ALF preserved the trabecular micro-architecture and cortical bone porosity. Furthermore, the combination treatment of ZOL and ALF corrected the decrease in serum calcium and increase in serum alkaline phosphatase and the tartarate-resistant acid phosphatase level better than single-drug therapy using ZOL or ALF in OVX rats. In addition, the combination treatment of ZOL and ALF corrected the increase in urine calcium, phosphorous and creatinine levels better than single-drug therapy using ZOL or ALF in OVX rats. These data suggest that the combination treatment of ZOL and ALF has a therapeutic advantage over each monotherapy for the treatment of osteoporosis.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

As rapid brain development occurs during the neonatal period, environmental manipulation during this period may have a significant impact on sleep and memory functions. Moreover, rapid eye movement (REM) sleep plays an important role in integrating new information with the previously stored emotional experience. Hence, the impact of early maternal separation and isolation stress (MS) during the stress hyporesponsive period (SHRP) on fear memory retention and sleep in rats were studied. The neonatal rats were subjected to maternal separation and isolation stress during postnatal days 5-7 (6 h daily/3 d). Polysomnographic recordings and differential fear conditioning was carried out in two different sets of rats aged 2 months. The neuronal replay during REM sleep was analyzed using different parameters. MS rats showed increased time in REM stage and total sleep period also increased. MS rats showed fear generalization with increased fear memory retention than normal control (NC). The detailed analysis of the local field potentials across different time periods of REM sleep showed increased theta oscillations in the hippocampus, amygdala and cortical circuits. Our findings suggest that stress during SHRP has sensitized the hippocampus amygdala cortical loops which could be due to increased release of corticosterone that generally occurs during REM sleep. These rats when subjected to fear conditioning exhibit increased fear memory and increased, fear generalization. The development of helplessness, anxiety and sleep changes in human patients, thus, could be related to the reduced thermal, tactile and social stimulation during SHRP on brain plasticity and fear memory functions. (C) 2014 Elsevier B.V. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The interaction of a Lewis acid with a Lewis base results in the formation of a Lewis acid base adduct. Understanding Lewis acids and bases is central to conceptualizing chemical interactions and constitutes a major portion of metal ligand chemistry. Sterically encumbered/constrained Lewis pairs cannot form acid-base adducts, but such `Frustrated Lewis Pairs' (FLPs), with their unquenched electronic demands can be elegantly used to simultaneously react with a third species, resulting in unusual reactivity of small molecules. Such unusual reactions, explored only in the last few years, have found several applications, e.g., heterolytic splitting of H-2, activation of small molecules (CO2, N2O, etc.). FLPs have opened new opportunities in synthetic chemistry, covering organic, main group as well as transition metal chemistry. The design strategies adopted for FLP systems and their unique reactivity are discussed here.