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BACKGROUND: Alzheimer's disease (AD) is characterized by progressive and irreversible cognitive and memory impairment. The discovery of familial forms of AD (fAD) in association with specific gene mutations facilitated the generation of numerous rodent models. These models in turn proved valuable for the study of molecular mechanisms underlying AD pathogenesis, and facilitated translational research and preclinical drug development. This study aimed to introduce a new rat model of AD simulating some aspects of the sporadic cases of disease. METHODS: Lentiviruses (LV) encoding human amyloid protein precursor (APP) bearing the fAD-linked Swedish and Indiana mutations (APPSw/Ind) were injected bilaterally in the hippocampus of adult rats. Passive avoidance and spatial memory performance were assessed 30 and 45 days post-injection, respectively. APP overexpression, intracellular accumulation of ß-amyloid (Aß) peptide, and astrogliosis were also evaluated using immunohistochemical procedures. RESULTS: Passive avoidance memory deficit was followed by impairments in spatial memory retrieval in LV (APPSw/Ind)-injected rats, compared to control animals. In addition, LV expression of APPSw/Ind was associated with intraneuronal accumulation of Aß, and reactive astrocytosis, two major AD hallmarks. CONCLUSION: Results from this work suggest that LV-mediated delivery of APPSw/Ind in adult rats represents a cost and time-effective animal model for the study of mechanisms underlying APP-linked fAD pathogenesis. The relevance of this animal model to the study of sporadic AD is discussed.

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γ-Secretase is an important contributing enzyme in Alzheimer's disease and is therefore an important therapeutic target. However, the impact of γ-secretase inhibition is not well studied in acute neuroinflammation induced by systemic infection. In this study the influence of γ-secretase on the expression of some proinflammatory markers was assessed in the acute phase as well as the subsiding phase of neuroinflammation. Cerebral γ-secretase cleavage activity was measured by a fluorometric assay after lipopolysaccharide (LPS) intraperitoneal administration. Time profiles of TNF-α and COX-II expression were then determined to detect the time points relevant to the maximal inflammatory responses and the subsequent recovery phase. γ-Secretase activity coincident with TNF-α protein expression returned to its basal level till 8-12 h after systemic challenge with low dose LPS while COX-II over expression lasted for 48-72 h later. Pharmacological inhibition of γ-secretase with local or systemic administration of DAPT (N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester) was performed to indicate the results on the developmental and sinking phases of inflammatory responses in 6 and 72 h post LPS respectively. Our results demonstrate that both local and systemic modulation of γ-secretase hyper-activity with DAPT increase the duration of TNF-α, COX-II, and NFκB induction. We consistently found mild augmented apoptosis in animals treated with DAPT as determined by measuring cleaved caspase-3 expression and by TUNEL assay 72 h following LPS injection. These results suggest that γ-secretase modulation interferes with certain immune regulatory pathways which may restrict some inflammatory transcription factors such as NFκB.

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Neuronal apoptosis in neurodegenerative diseases is correlated with inflammatory reactions. The beneficial or detrimental role of apoptosis in neuroinflammation is unclear. In this study, we injected ß-amyloid peptide into the rat cortex for induction of neuroinflammation in hippocampus. We observed an increase in TNF-α as an inflammatory cytokine and caspase3 and TUNEL-positive cells as apoptotic marker. As far as ability of TNF-α to induce apoptosis or activate NF-kß, the question is what will happen if the balance between two pathways is disturbed by inhibition of apoptosis. Using caspase inhibitors, we inhibited apoptosis and assessed NF-kß, Hsp 70 (a hallmark of cancer), cmyc (proto-oncogene) and p53 (tumor suppressor protein). There was an unexpected decrease in NF-kß while Hsp70 and cmyc upregulated and p53 decreased. These results imply that inhibition of apoptosis due to increased susceptibility to abnormal mitosis may not provide a reliable strategy for treatment of neuroinflammatory diseases.

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Chronic pain has been reported to induce apoptosis. Both chronic excitation of neural pathways involved in pain transmission and control and the stress of pain may be potentially involved in apoptosis induced by pain. Here, we have investigated their possible role in pain-induced apoptosis. Inflammatory pain was induced by injection of formalin in intact and adrenalectomized (ADX) rats. Following exposure to repeated injections of 5% formalin, we detected Bax, Bcl-2, pro-caspase and activated caspase-3 proteins using immunoblotting. The results were compared with those obtained from animals suffered from chronic immobilization stress (IMO). These results showed an increased ratio of Bax/Bcl-2 and activated caspase-3 in hippocampus and dorsal lumbar spinal cord of animals treated with pain and IMO stress; these effects were reduced in ADX animals. On the other hand, the remaining apoptotic effect of pain in adrenalectomized rats was also significant. We surmise that both chronic neural activation and the stress induced by pain are involved in pain-induced apoptosis.

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Antinociceptive potency of opioids is greater against various noxious stimuli in animals with peripheral inflammation. Opioid agonists stimulate activation of G-protein-coupled receptor. Changes in the resting levels of G-protein subtypes could have an effect on intracellular signalling pathways. The present study was designed to investigate the effects of analgesic morphine treatment on the level G-protein subunits mRNA in the presence and absence of inflammation. Our results showed that the carrageenan administration increased G-protein subunits. Administration of analgesic dose of morphine alone and in the presence of inflammation induced different alterations in the levels of G-protein mRNA. Taken together, the results obtained using real time RT-PCR suggested that G-protein genes expression levels following the acute administration of morphine between animals with and without inflammation could influence, at least in part, analgesic responsiveness.

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UNLABELLED: This study sought to evaluate the bioequivalence of Iminoral (test) versus Neoral (reference) in healthy volunteers, as well as safety and efficacy of Iminoral treatment in renal transplant recipients following conversion from Neoral. METHODS: After an overnight fast, 18 healthy volunteers received the assigned treatment (test or reference, 200 mg single dose) in a cross-over fashion with a washout period of 14 days. The blood samples were drawn at various times after drug administration. Cyclosporine blood concentration was measured by high-performance liquid chromatography using an ultraviolet detector. In the second phase of study, stable renal transplant patients who were on Neoral were enrolled in the study in an open-label manner. They were converted from Neoral to Iminoral based on a 1:1 dose equivalence. Cyclosporine trough levels and changes in serum creatinine, lipid profile, electrolytes, and uric acid were measured before and periodically after conversion for 6 months. RESULTS: The 90% confidence interval of the test/reference ratio was within the acceptable limits of 0.8 to 1.25. Relative bioavailability of Iminoral in healthy subjects was 99.0%. There was no significant difference in cyclosporine concentrations and serum creatinines following conversion to Iminoral in renal transplant patients (n=41). There were no reports of major toxicity or of graft rejection and no need for dose adjustment related to Iminoral. CONCLUSIONS: Single doses of Neoral and Iminoral are bioequivalent in healthy subjects. Renal transplant recipients maintained on Neoral can be safely and effectively converted to Iminoral on a 1:1 conversion ratio.

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Most drugs of abuse increase dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) release in the shell of the nucleus accumbens. The effects of ascorbate, which is known to modulate dopamine neurotransmission, on the extracellular level of DOPAC in the nucleus accumbens of naive rats and of rats treated acutely with morphine were studied by using in vivo microdialysis and high performance liquid chromatography with electrochemical detection (HPLC-ECD). Acute morphine (20 mg/kg ip) treatment increased the level of DOPAC in the nucleus accumbens to approximately 170% of basal level. Acute treatment with ascorbate (500 mg/kg ip) alone did not alter nucleus accumbens' DOPAC level, but pretreatment with ascorbate (500 mg/kg ip) 30 min before morphine administration attenuated the effects of acute morphine on the level of DOPAC. These results suggest that ascorbate modulates the mesolimbic dopaminergic pathway.

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Recent studies suggest that peripheral morphine may represent a valuable treatment in acute inflammatory painful diseases through peripheral or central mechanisms. In the present study, anti-inflammatory effects of systemic morphine on carrageenan-induced hind paw oedema were examined in a model of peripheral acute oedema in mice. Carrageenan induced a time-dependent inflammation that was maximal 3 h after administration. While intraperitoneal administration of morphine sulfate at a low dose (1 mg/kg) increased carrageenan-induced hind paw oedema, intraperitoneal injection of morphine sulfate at a high dose (7 mg/kg) resulted in significant anti-inflammatory effects on carrageenan-induced hind paw oedema. These anti-inflammatory effects were blocked by pretreatment with naloxone. Measuring the serum levels of interleukin-1beta revealed that increases in serum levels of this cytokine were involved in morphine anti-inflammatory effects. Pretreatment with naloxone decreased interleukin-1beta serum levels near to those of control group. In conclusion, these data demonstrate that morphine produced pro- or anti-inflammatory effects in a dose-dependent manner through peripheral or central mechanisms. The observed anti-inflammatory effects may be due to an increase in the cytokine production and/or release by host immune systems.

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Although migraine affects about 15% of population and many studies have been performed to find the mechanism and a successful management, the physiopathology of migraine is still largely unknown. The possibility of an immunoglobulin E (IgE)-mediated allergic mechanism and the role of histamine remain controversial. The aim of the present study was to evaluate serum total IgE and histamine levels in migraine patients and the influence of allergy on them. Seventy patients (18-58 years) with migraine without aura were divided into two groups according to their history of allergy (60% with and 40% without allergy). Serum samples were collected during fasting without allowing any premedication during the two periods of attack and remission. There was a control group containing 45 healthy volunteers. Serum total IgE and histamine levels were measured by enzyme-linked immunosorbent assay and fluorimetric methods, respectively. Mean and standard errors of serum histamine (ng/ml) and total IgE (IU/ml) levels were found in the control group to be 48.16 +/- 2.70 and 38.31 +/- 3.20, in the migraine with allergy group 159.11 +/- 4.60 and 303.30 +/- 42.50 and in the migraine without allergy group 105.01 +/- 8.50 and 79.07 +/- 2.70, respectively. Total IgE levels in migraine with allergy group were found to be significantly (P < 0.0001) above that in the control and another group, suggesting an influence of an IgE-mediated mechanism on migraine. Although the plasma histamine levels, which were significantly elevated (P < 0.0001) in patients with migraine, both during headache and symptom-free periods, when compared with the control group, indicate that there is an increased susceptibility to histamine in allergic conditions, this molecule has also an unrelated role in migraine. The relationship between allergy and migraine can be based, in part, on an IgE-mediated mechanism, and histamine release plays an important role. Thus, the avoidance of allergic conditions in migraine patients may be a simple, helpful way for prophylaxis or their treatment.

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Although migraine affects about 15 % of the population, and many studies have been performed to find the mechanism and successful management, the physiopathology of migraine is still largely unknown. The possibility of an IgE-mediated allergic mechanism and the role of histamine remains controversial. The aim of the present study was the evaluation of serum total IgE and histamine levels in migraine patients and the intluence of allergy on them. 70 patients (18-58 years) with migraine without aura were divided in to 2 groups according to their history of allergy (60% with and 40% without allergy). Serum samples were collected during fasting without allowing any premedication in 2 conditions of attack and remission periods. There was a control group containing 45 healthy volunteers. Serum total IgE and histamine levels were measured by ELISA and fluorimetric methods respectively. Mean and standard error of serum histamine (ng/ml) and total IgE (lU/mI) levels were found in control group as 48.16+/-2.70, 38.31+/-3.20 and in migraine with an allergy group as 159.11+/-4.60, 303.30+/-42.50 and in migraine without an allergy group as 105.01 +/-8.50, 79.07+/-2.70 respectively. Total IgE levels in migraine group with allergy were found significantly (P<0.0001) above the control and another group suggesting an influence of an IgE-mediated mechanism on migraine. Plasma histamine levels were significantly elevated (P<0.0001) in patients with migraine both during headache and symptom-free periods compared with control group although it shows that there is an increased susceptibility to histamine in allergic conditions, nonetheless this molecule has also an unrelated role in migraine. The relationship between allergy and migraine can be based in part on IgE-mediated mechanism, with histamine release playing an important role. Thus avoidance of allergic conditions in migraine patients may be a simple helpful way to prophylaxis or their treatment.

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Neuropeptides, possessing specific and functional receptors on various cells of the immune system, have the potential to regulate immune responses; and the macrophages as important components of defense against various agents, are at their influence. In this study the effect of neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP) on IL-1 beta production by herpes simplex type-1 (HSV-1)-infected and also uninfected mouse peritoneal macrophages were considered. Each neuropeptide separately has upregulated IL-1 beta production by HSV- 1 infected macrophages with the greatest effect at the concentrations of 1 09M for both SP and CGRP, but no synergistic effect on IL-1 production has been observed in the presence of both neuropeptides at optimal concentrations. IL-113 production by uninfected macrophages was also moderately enhanced in the presence of each neuropeptide, but not in the presence of both neuropeptides simultaneously. It can be concluded that IL-1 beta production, which is part of macrophage mediated inflammatory response to HSV-l, is enhanced by specific doses of neuropeptides.

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Changes in vascular responsiveness are the basis for some of the cardiovascular complications in cholestasis. Since the duration of cholestasis is important in determining the degree of the complications, we investigated the time-course dependent evolution of vascular relaxation responsiveness in the aortic rings of cholestatic rats. Acetylcholine-induced endothelium-dependent relaxation was investigated in the isolated aortic rings of unoperated, sham-operated and two-, five-, seven- and fourteen-day bile-duct ligated rats. There was a significant reduction in acetylcholine-induced relaxation of the aortic rings by the second day after the bile-duct ligation operation, compared to those of unoperated and sham-operated groups, but more reduction still occurs in 5- and 7-day bile-duct ligated groups, reaching a plateau by the seventh day. The relaxation response to sodium nitroprusside in the aortic rings of the unoperated and the 7-day bile-duct ligated rats did not differ, implying the intact smooth muscle component of the relaxation pathway. L-NAME ( N(omega)-nitro-L-arginine methyl ester), a nitric oxide (NO) synthase inhibitor, attenuated the acetylcholine-induced relaxation in both groups (unoperated and bile-duct ligated), while L-arginine prevents this inhibitory effect. Indomethacin potentiated the acetylcholine-induced relaxation in the aortic rings of the bile-duct ligated rats while it has no effect on unoperated controls, providing evidence for the possible role of vasoconstrictor prostanoids in cholestasis-induced reduction in acetylcholine-induced relaxation. These results state that the reduced acetylcholine-induced relaxation in the cholestatic aortic rings during the first week, when no portal hypertension was reported to be present, may be due to the decreased acetylcholine-induced NO release from endothelium or increased NO inactivation.

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Anti-inflammatory and antipyretic effects of the Trigonella foenum-graecum (TFG) leaves extract, an Iranian medicinal plant, were examined. For anti-inflammatory activity, the formalin-induced edema model was used. Hyperthermia was induced by intraperitoneal injection of 20% (w/v) aqueous suspension of brewer's yeast. Sodium salicylate (SS) was used as a positive control. Both TFG and SS significantly reduced formalin-induced edema in single dose (TFG 1000 and 2000 mg/kg, SS 300 mg/kg) and chronic administration (TFG 1000 mg/kg and SS 300 mg/kg). TFG and SS also significantly reduced hyperthermia induced by brewer's yeast in 1 and 2 h after their administration. The results indicate that the TFG leaves extract possess anti-inflammatory as well as antipyretic properties in both i.p. and p.o. administration. Phytochemical studies indicate that alkaloids, cardiac glycosides, and phenols are the major component in the extract. Although existence of three anti-inflammatory, analgesic and antipyretic effects in this extract suggest a NSAID-like mechanism for it, but the presence of alkaloids, the absence of other effective compounds such as flavonoids, saponins, steroids, etc., and also its analgesic effect on tail-flick test that usually is not produced by NSAIDs, suggest another mechanism for the extract. So the possibility of alkaloids as effective compounds, in this extract, increases.

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A simple high-performance liquid chromatographic procedure was developed for the determination of ranitidine in human plasma. The method entailed direct injection of the plasma samples after deproteination using perchloric acid. The chromatographic separation was accomplished with an isocratic elution using mobile phase consisting of 21 mM disodium hydrogen phosphate-triethylamine-acetonitrile (1000:60:150, v/v), pH 3.5. Analyses were run at a flow-rate of 1.3 ml/min using a microbondapak C18 column and ultraviolet detection at a wavelength of 320 nm. The method was specific and sensitive, with a quantification limit of approximately 20 ng/ml and a detection limit of 5 ng/ml at a signal-to-noise ratio of 3:1. The mean absolute recovery was about 96%, while the within- and between-day coefficient of variation and percent error values of the assay method were all less than 8%. The linearity was assessed in the range of 20-1000 ng/ml plasma, with a correlation coefficient of greater than 0.999. This method has been used to analyze several hundred human plasma samples for bioavailability studies.

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The regulation of T helper (Th)1- and Th2-type cytokine patterns is important in the final outcome of leishmaniasis in human and murine models. We examined the efficacy of garlic therapy or a combination of garlic and an antimonial drug (glucantime) in promoting healing and regulation of Th1/Th2 cytokine patterns in highly susceptible BALB/c mice infected with Leishmania major. Separate groups of infected mice received 20 mg/kg/day garlic, 60 mg/kg/day glucantime or a combination of the two, from day 30 after infection for 2 weeks. An enzyme-linked immunosorbant assay (ELISA) was performed on spleen cell culture supernatants for interferon(IFN)-gamma interleukin(IL)-2, IL-4 and IL-10. The results indicate that garlic therapy is more effective than the usual antileishmanial drug in curing the infection. Garlic-treated mice developed Th1-type cytokine responses. In contrast, glucantime therapy led to a Th2-type response in the control group with a lower level of IL-2. However, a combination of garlic and glucantime treatment was more effective than either treatment alone, and resulted in a Th1-type response similar to that which developed with garlic treatment. These results suggest that garlic extract in combination with an antimonial drug, may provide effective therapy against L. major. The immunomodulatory properties of garlic were elucidated in terms of shifting the cytokine response to a Th1-type pattern and therefore causing the protective response.

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Several methods for measuring inflammation are available that rely on the parameters changing during inflammation. The most commonly used methods estimate the volume of edema formed. In this study, we present a novel method for measuring the volume of pathologically or artificially induced edema. In this model, a liquid column is placed on a balance. When an object is immersed, the liquid applies a force F to attempt its expulsion. Physically, F is the weight (W) of the volume of liquid displaced by that part of the object inserted into the liquid. A balance is used to measure this force (F=W).Therefore, the partial or entire volume of any object, for example, the inflamed hind paw of a rat, can be calculated thus, using the specific gravity of the immersion liquid, at equilibrium mass/specific gravity=volume (V). The extent of edema at time t (measured as V) will be V(t)-V(o). This method is easy to use, materials are of low cost and readily available. It is important that the rat paw (or any object whose volume is being measured) is kept from contacting the wall of the column containing the fluid whilst the value on the balance is read.

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In this study, probable antinociceptive and anti-inflammatory effects of Elaeagnus angustifolia fruit components, were evaluated. For evaluation of antinociceptive effects, the chronic (formalin test) and acute (tail-flick) pain models of rats were used. For the anti-inflammatory effects, the paw inflammation model was used through subcutaneous injection of 5% formalin to the paw of male rats. Water extracts of the fruit and its components in the single dose were assessed through comparison with the antinociceptive and anti-inflammatory effects of sodium salicylate (SS) as a positive control. Administration of 300 mg/kg of SS (i.p.) had no effect on tail flick latency, while 1000 mg/kg of total (i.p. and p.o.) and endocarp (i.p.) extract, increased this latency (P<0.01, P<0.001, respectively), which was not reversed by naloxone (2 mg/kg). In the formalin test, SS (300 mg/kg, i.p.) and the extract (1000 mg/kg, p.o. ) alleviated the animals nociception in the second phase, while in the first phase they were not effective. The total and endocarp extracts (1000 mg/kg, i.p.) showed a significant effect on both phases (P<0.01, P<0.001, respectively) which was also not reversed by naloxone (2 mg/kg, i.p.). In the acute anti-inflammatory test, the total extract and the aqueous extract of individual fruit components showed a significant effect (P<0.001). This anti-inflammatory effect was not significant compared with the anti-inflammatory effect of SS. Because of the extract effect on the tail-flick latency and both phases of the formalin test, the site of its analgesic action is probably central, and the mechanism of antinociceptive action of the extract are not related to the opioid system. Our phytochemical studies indicated that aqueous extract of E. angustifolia fruit contains flavonoids, terpenoids and cardiac glycosides.

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The rate and degree of subsensitivity development to morphine (mu-opioid receptor, preferred, but not selective agonist) and U50488H (highly selective kappa-opioid receptor agonist) were assessed in vitro on guinea pig ileum (GPI) of cholestatic animals 2, 5, and 7 days after bile duct ligation. In addition to this phenomenon of morphine, the effects of U50488H and SNC 80 (highly selective delta-opioid receptor agonist) were studied in vitro on mice vas deferens (MVD) of cholestatic animals 2, 5, 7, 10, and 15 days after bile duct ligation. The IC(50) for each compound was determined in these preparations. The ratio of the IC(50) in bile duct-ligated animals to sham and control animals provides a quantitative index for the degree of subsensitivity development to each agonist. For any given time, the highest degree of subsensitivity to morphine was observed in GPI of cholestatic animals, whereas in MVD obtained from the cholestatic animals, the highest degree of subsensitivity developed to inhibitory effect of SNC 80. The subsensitivity development in cholestatic animals was time dependent; in GPI the maximum subsensitivity developed after 7 days of the operation, whereas the maximum subsensitivity in MVD developed 15 days after bile duct ligation. Moreover, subsensitivity to exogenous acetylcholine and norepinephrine in GPI and MVD, respectively, did not develop in the presence of subsensitivity to opioids in cholestatic animals. Significant accumulation of endogenous opioids in plasma of cholestatic animals has been shown in several studies and this may account for a significant development of subsensitivity to inhibitory effects of opioid agonists.

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The involvement of spinal serotonergic system in testosterone influence on formalin-induced pain was studied in male rats. Four weeks after castration, there was an analgesia in the late phase of formalin test that was reversed by intraperitoneal injection of testosterone enanthate (1 mg/kg) for 3 days. Flutamide (testosterone antagonist) produce analgesia in the late phase on intraperitoneal (10 mg/kg, IP) and intrathecal (60 microg/rat, IT) injections, but not on intracerebroventricular (60 microg/rat, ICV) administration. The antinociceptive effect of castration and IP flutamide (10 mg/kg) was abolished by pretreatment with 5,7-dihydroxytryptamine (5,7-DHT, 100 microg/rat, IT). IT-administered 5-HT (100 microg/rat) produced analgesia in the early and late phase of formalin test. Microdialysis sampling was used to characterize the extracellular concentration of 5-hydroxytryptamine (5-HT, serotonin) in the dorsal horn of the lumbar spinal cord. This technique demonstrated that levels of 5-HT were increased in 4-week castrated and IP flutamide (10 mg/kg) injected rats. The results may indicate that the analgesia produced by castration and flutamide administration is mediated through functional alteration in spinal cord serotonergic system.

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Barberry (Berberis vulgaris) is a well known medicinal plant in Iran and has also been used as food. The antihistaminic and anticholinergic activity of aqueous extract of barberry fruits were investigated on isolated guinea-pig ileum, and dose response curves of histamine and acetylcholine with and without extract were plotted. The pA2 values for antihistaminic activity of extract and dexchlorpheniramine were calculated (extract; pA2 +/- S.E.M. = 4.50 +/- 0.01[-log C (g/l)]; dexchlorpheniramine; pA2 +/- S.E.M. = 9.36 +/- 0.14[-log C (M)]) and compared with each other. The pA2 values for anticholinergic activity of extract and atropine were also calculated (extract, pA2 +/- S.E.M. = 4.37 +/- 0.03[-log C (g/l)]; atropine, pA2 +/- S.E.M. = 8.99 +/- 0.13[-log C (M)]) and compared. The results indicated antihistaminic and anticholinergic activity of extract that seems to be of the competitive type.

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