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1.
Mol Ther Methods Clin Dev ; 31: 101161, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38094199

RESUMO

(AAV)-mediated episomal gene replacement therapy for monogenic liver disorders is currently limited in pediatric settings due to the loss of vector DNA, associated with hepatocyte duplication during liver growth. Genome editing is a promising strategy leading to a permanent and specific genome modification that is transmitted to daughter cells upon proliferation. Using genome targeting, we previously rescued neonatal lethality in mice with Crigler-Najjar syndrome. This rare monogenic disease is characterized by severe neonatal unconjugated hyperbilirubinemia, neurological damage, and death. Here, using the CRISPR-Staphylococcus aureus Cas9 (SaCas9) platform, we edited the disease-causing mutation present in the Ugt1a locus of these mice. Newborn mice were treated with two AAV8 vectors: one expressing the SaCas9 and single guide RNA, and the other carrying the Ugt1a homology regions with the corrected sequence, while maintained in a temporary phototherapy setting rescuing mortality. We observed a 50% plasma bilirubin reduction that remained stable for up to 6 months. We then tested different Cas9:donor vector ratios, with a 1:5 ratio showing the greatest efficacy in lowering plasma bilirubin, with partial lethality rescue when more severe, lethal conditions were applied. In conclusion, we reduced plasma bilirubin to safe levels and partially rescued neonatal lethality by correcting the mutant Ugt1a1 gene of a Crigler-Najjar mouse model.

2.
Front Aging Neurosci ; 14: 960314, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36275011

RESUMO

Increasing evidence suggests that mitochondrial dysfunction and aberrant release of mitochondrial reactive oxygen species (ROS) play crucial roles in early synaptic perturbations and neuropathology that drive memory deficits in Alzheimer's disease (AD). We recently showed that solubilized human amyloid beta peptide 1-42 (hAß1-42) causes rapid alterations at glutamatergic synapses in the entorhinal cortex (EC) through the activation of both GluN2A- and GluN2B-containing NMDA receptors. However, whether disruption of mitochondrial dynamics and increased ROS contributes to mechanisms mediating hAß1-42-induced synaptic perturbations in the EC is unknown. Here we assessed the impact of hAß1-42 on mitochondrial respiratory functions, and the expression of key mitochondrial and synaptic proteins in the EC. Measurements of mitochondrial respiratory function in wild-type EC slices exposed to 1 µM hAß1-42 revealed marked reductions in tissue oxygen consumption and energy production efficiency relative to control. hAß1-42 also markedly reduced the immunoexpression of both mitochondrial superoxide dismutase (SOD2) and mitochondrial-cytochrome c protein but had no significant impact on cytosolic-cytochrome c expression, voltage-dependent anion channel protein (a marker for mitochondrial density/integrity), and the immunoexpression of protein markers for all five mitochondrial complexes. The rapid impairments in mitochondrial functions induced by hAß1-42 were accompanied by reductions in the presynaptic marker synaptophysin, postsynaptic density protein (PSD95), and the vesicular acetylcholine transporter, with no significant changes in the degradative enzyme acetylcholinesterase. We then assessed whether reducing hAß1-42-induced increases in ROS could prevent dysregulation of entorhinal synaptic proteins, and found that synaptic impairments induced by hAß1-42 were prevented by the mitochondria-targeted antioxidant drug mitoquinone mesylate, and by the SOD and catalase mimetic EUK134. These findings indicate that hAß1-2 can rapidly disrupt mitochondrial functions and increase ROS in the entorhinal, and that this may contribute to synaptic dysfunctions that may promote early AD-related neuropathology.

3.
Int J Mol Sci ; 23(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36142606

RESUMO

Bilirubin is a heme catabolite and Ugt1a1 is the only enzyme involved in the biological elimination of bilirubin. Partially functional or non-functional Ugt1a1 may result in neuronal damage and death due to the accumulation of unconjugated bilirubin in the brain. The understanding of the role of alternative bilirubin detoxification mechanisms that can reduce bilirubin toxicity risk is crucial for developing novel therapeutic strategies. To provide a proof-of-principle showing whether activation of alternative detoxification pathways could lead to life-compatible bilirubin levels in the absence of Ugt1a1 activity, we used Ugt1-/- hyperbilirubinemic mice devoid of bilirubin glucuronidation activity. We treated adult Ugt1-/- mice with TCPOBOP, a strong agonist of the constitutive androstane receptor (CAR). TCPOBOP treatment decreased plasma and liver tissue bilirubin levels by about 38%, and resulted in the transcriptional activation of a vast array of genes involved in bilirubin transport and metabolism. However, brain bilirubin level was unaltered. We observed ~40% degradation of bilirubin in the liver microsomes from TCPOBOP treated Ugt1-/- mice. Our findings suggest that, in the absence of Ugt1a1, the activation of alternative bilirubin clearance pathways can partially improve hyperbilirubinemic conditions. This therapeutic approach may only be considered in a combinatorial manner along with other treatments.


Assuntos
Bilirrubina , Hiperbilirrubinemia , Animais , Modelos Animais de Doenças , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Heme/metabolismo , Fígado/metabolismo , Camundongos
4.
PLoS One ; 17(8): e0271131, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35939438

RESUMO

Estrogens are thought to contribute to cognitive function in part by promoting the function of basal forebrain cholinergic neurons that project to the hippocampus and cortical regions including the entorhinal cortex. Reductions in estrogens may alter cognition by reducing the function of cholinergic inputs to both the hippocampus and entorhinal cortex. In the present study, we assessed the effects of ovariectomy on proteins associated with cholinergic synapses in the entorhinal cortex. Ovariectomy was conducted at PD63, and tissue was obtained on PD84 to 89 to quantify changes in the degradative enzyme acetylcholinesterase, the vesicular acetylcholine transporter, and muscarinic M1 receptor protein. Although the vesicular acetylcholine transporter was unaffected, ovariectomy reduced both acetylcholinesterase and M1 receptor protein, and these reductions were prevented by chronic replacement of 17ß-estradiol following ovariectomy. We also assessed the effects of ovariectomy on the cholinergic modulation of excitatory transmission, by comparing the effects of the acetylcholinesterase inhibitor eserine on evoked excitatory synaptic field potentials in brain slices obtained from intact rats, and from ovariectomized rats with or without 17ß-estradiol replacement. Eserine is known to prolong the effects of endogenously released acetylcholine, resulting in an M1-like mediated reduction of glutamate release at excitatory synapses. The reduction in excitatory synaptic potentials in layer II of the entorhinal cortex induced by 15-min application of 10 µM eserine was greatly reduced in slices from ovariectomized rats as compared to intact rats and ovariectomized rats with replacement of 17ß-estradiol. The reduced modulatory effect of eserine is consistent with the observed changes in cholinergic proteins, and suggests that reductions in 17ß-estradiol following ovariectomy lead to impaired cholinergic function within the entorhinal cortex.


Assuntos
Acetilcolinesterase , Córtex Entorrinal , Animais , Colinérgicos/farmacologia , Córtex Entorrinal/fisiologia , Estradiol/farmacologia , Estrogênios/farmacologia , Potenciais Pós-Sinápticos Excitadores , Feminino , Humanos , Ovariectomia , Fisostigmina/farmacologia , Ratos , Receptor Muscarínico M1 , Transmissão Sináptica/fisiologia , Proteínas Vesiculares de Transporte de Acetilcolina
5.
Neurobiol Aging ; 105: 296-309, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34144329

RESUMO

The hippocampus and entorhinal cortex (EC) accumulate amyloid beta peptides (Aß) that promote neuropathology in Alzheimer's disease, but the early effects of Aß on excitatory synaptic transmission in the EC have not been well characterized. To assess the acute effects of Aß1-42 on glutamatergic synapses, acute brain slices from wildtype rats were exposed to Aß1-42 or control solution for 3 hours, and tissue was analyzed using protein immunoblotting and quantitative PCR. Presynaptically, Aß1-42 induced marked reductions in synaptophysin, synapsin-2a mRNA, and mGluR3 mRNA, and increased both VGluT2 protein and Ca2+-activated channel KCa2.2 mRNA levels. Postsynaptically, Aß1-42 reduced PSD95 and GluN2B protein, and also downregulated GluN2B and GluN2A mRNA, without affecting scaffolding elements SAP97 and PICK1. mGluR5 mRNA was strongly increased, while mGluR1 mRNA was unaffected. Blocking either GluN2A- or GluN2B-containing NMDA receptors did not significantly prevent synaptic changes induced by Aß1-42, but combined blockade did prevent synaptic alterations. These findings demonstrate that Aß1-42 rapidly disrupts glutamatergic transmission in the EC through mechanisms involving concurrent activation of GluN2A- and GluN2B-containing NMDA receptors.


Assuntos
Peptídeos beta-Amiloides/efeitos adversos , Córtex Entorrinal/citologia , Córtex Entorrinal/metabolismo , Ácido Glutâmico/metabolismo , Fragmentos de Peptídeos/efeitos adversos , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapses/metabolismo , Transmissão Sináptica/efeitos dos fármacos , Doença de Alzheimer/etiologia , Peptídeos beta-Amiloides/metabolismo , Animais , Masculino , Fragmentos de Peptídeos/metabolismo , Ratos Long-Evans
6.
Anat Cell Biol ; 54(2): 212-224, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33967032

RESUMO

Bisphenol A is a chemical used primarily as a monomer in the production of polycarbonate plastics and epoxy resins. It is a synthetic chemical compound that is produced in billions of pounds annually, and tagged as an endocrine disruptor. Bisphenol A is a high production synthetic chemical compound that is used in the production of many consumables and equipments of daily consumption and use by man. Growing interest in possible health threats posed by endocrine disrupting chemicals (bisphenol-A inclusive), as these substances are in our environment, food, and many consumer products. Therefore, this study aims to determine bisphenol-A effects on the hypothalamo-pituitary-ovarian axis, and role of melatonin in this regard. Forty-two Wistar rats were bred, grouped into 7, with each group consisting of 6 rats. Experimental groups were administered low and high doses of bisphenol-A and melatonin, starting from day 19, and was continued for 7 weeks orally. They were left to develop into full adults and were sacrificed on day 120±4 days. Blood samples, hypothalamus, pituitary and ovarian tissues were excised for biochemical and tissue antioxidants assays as well as genetic studies. Results show elevated gonadotropin and androgen levels. There was disruption of reactive oxygen species in the ovarian tissues, as well as alterations in the expression of genes that regulate reproduction at the hypothalamus and pituitary levels. Conclusion of early exposure to bisphenol-A is associated with prolonged duration of disruption of reproductive functions in female Wistar rats, which persist long after cessation of the exposure. Melatonin antioxidant effects give some promising outturns against bisphenol-A induced toxicities.

7.
Neurotoxicol Teratol ; 86: 106982, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33845156

RESUMO

Despite reports that quinoline antimalarials including chloroquine (Chq) exhibit idiosyncratic neuropsychiatric effects even at low doses, the drug continues to be in widespread use during pregnancy. Surprisingly, very few studies have examined the potential neurotoxic action of Chq exposure at different points of gestation or how this phenomenon may affect neurophysiological well-being in later life. We therefore studied behavior, and the expression of specific genes and neurochemicals modulating crucial neural processes in offspring of rats exposed to prophylactic dose of Chq during different stages of gestation. Pregnant rats were injected 5 mg/kg/day (3 times) of Chq either during early- (first week), mid- (second week), late- (third week), or throughout- (all weeks) gestation, while controls received PBS injection. Behavioral characterization of offspring between postnatal days 15-20 in the open field, Y-maze, elevated plus and elevated zero mazes revealed that Chq evoked anxiogenic responses and perturbed spatial memory in rats, although locomotor activity was generally unaltered. In the prefrontal cortex (PFC), hippocampus and cerebellum of rats prenatally exposed to Chq, RT-qPCR analysis revealed decreased mRNA expression of presynaptic marker synaptophysin, which was accompanied by downregulation of postsynaptic marker PSD95. Synaptic marker PICK1 expression was also downregulated in the hippocampus but was unperturbed in the PFC and cerebellum. In addition to recorded SOD downregulation in cortical and hippocampal lysates, induction of oxidative stress in rats prenatally exposed to Chq was corroborated by lipid peroxidation as evinced by increased MDA levels. Offspring of rats infused with Chq at mid-gestation and weekly treatment throughout gestation were particularly susceptible to neurotoxic changes, especially in the hippocampus. Interestingly, Chq did not cause histopathological changes in any of the brain areas. Taken together, our findings causally link intrauterine exposure to Chq with postnatal behavioral impairment and neurotoxic changes in rats.


Assuntos
Comportamento Animal/efeitos dos fármacos , Química Encefálica/efeitos dos fármacos , Cloroquina/toxicidade , Plasticidade Neuronal/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/psicologia , Animais , Ansiedade/induzido quimicamente , Ansiedade/psicologia , Feminino , Expressão Gênica/efeitos dos fármacos , Idade Gestacional , Aprendizagem em Labirinto/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Gravidez , Ratos , Memória Espacial/efeitos dos fármacos
8.
Biol Open ; 10(1)2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33495355

RESUMO

The entorhinal cortex (EC) is a vital component of the medial temporal lobe, and its contributions to cognitive processes and memory formation are supported through its extensive interconnections with the hippocampal formation. During the pathogenesis of Alzheimer's disease (AD), many of the earliest degenerative changes are seen within the EC. Neurodegeneration in the EC and hippocampus during AD has been clearly linked to impairments in memory and cognitive function, and a growing body of evidence indicates that molecular and functional neurodegeneration within the EC may play a primary role in cognitive decline in the early phases of AD. Defining the mechanisms underlying molecular neurodegeneration in the EC is crucial to determining its contributions to the pathogenesis of AD. Surprisingly few studies have focused on understanding the mechanisms of molecular neurodegeneration and selective vulnerability within the EC. However, there have been advancements indicating that early dysregulation of cellular and molecular signaling pathways in the EC involve neurodegenerative cascades including oxidative stress, neuroinflammation, glia activation, stress kinases activation, and neuronal loss. Dysfunction within the EC can impact the function of the hippocampus, which relies on entorhinal inputs, and further degeneration within the hippocampus can compound this effect, leading to severe cognitive disruption. This review assesses the molecular and cellular mechanisms underlying early degeneration in the EC during AD. These mechanisms may underlie the selective vulnerability of neuronal subpopulations in this brain region to the disease development and contribute both directly and indirectly to cognitive loss.This paper has an associated Future Leader to Watch interview with the first author of the article.


Assuntos
Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Suscetibilidade a Doenças , Córtex Entorrinal/metabolismo , Córtex Entorrinal/patologia , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Apoptose , Modelos Animais de Doenças , Humanos , Degeneração Neural/etiologia , Degeneração Neural/metabolismo , Neuroglia/imunologia , Neuroglia/metabolismo , Doenças Neuroinflamatórias/etiologia , Doenças Neuroinflamatórias/metabolismo , Doenças Neuroinflamatórias/patologia , Estresse Oxidativo , Receptores de N-Metil-D-Aspartato/metabolismo , Proteínas tau/metabolismo
9.
J Mol Neurosci ; 71(6): 1205-1220, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33420680

RESUMO

The hallmarks of Alzheimer's disease (AD) pathology include senile plaques accumulation and neurofibrillary tangles, which is thought to underlie synaptic failure. Recent evidence however supports that synaptic failure in AD may instead be instigated by enhanced N-methyl-D-aspartate (NMDA) activity, via a reciprocal relationship between soluble amyloid-ß (Aß) accumulation and increased glutamate agonist. While previous studies have shown Aß-mediated alterations to the glutamatergic system during AD, the underlying etiology of excitotoxic glutamate-induced changes has not been explored. Here, we investigated the acute effects of stereotaxic dentate gyrus (DG) glutamate injection on behavior and molecular expression of specific proteins and neurochemicals modulating hippocampal functions. Dependence of glutamate-mediated effects on NMDA receptor (NMDAR) hyperactivation was tested using NMDARs antagonist memantine. DG of Wistar rats (12-weeks-old) were bilaterally microinjected with glutamate (500 mM) with or without daily intraperitoneal (i.p.) memantine injection (20 mg/kg) for 14 days, while controls received either intrahippocampal/i.p. PBS or i.p. memantine. Behavioral characterization in open field and Y-maze revealed that glutamate evoked anxiogenic responses and perturbed spatial memory were inhibited by memantine. In glutamate-treated rats, increased NO expression was accompanied by marked reduction in profiles of glutathione-s-transferase and glutathione peroxidase. Similarly, glutamate-mediated increase in acetylcholinesterase expression corroborated downregulation of synaptophysin and PSD-95, coupled with initiation of reactive astrogliosis (GFAP). While neurofilament immunolocalization/immunoexpression was unperturbed, we found glutamate-mediated reduction in neurogenic markers Ki67 and PCNA immunoexpression, with a decrease in NR2B protein expression, whereas mGluR1 remains unchanged. In addition, increased expression of apoptotic regulatory proteins p53 and Bax was seen in glutamate infused rats, corroborating chromatolytic degeneration of granule neurons in the DG. Interestingly, memantine abrogated most of the degenerative changes associated with glutamate excitotoxicity in this study. Taken together, our findings causally link acute glutamate dyshomeostasis in the DG with development of AD-related behavioral impairment and molecular neurodegeneration.


Assuntos
Doença de Alzheimer/metabolismo , Comportamento Animal , Giro Denteado/metabolismo , Ácido Glutâmico/toxicidade , Doença de Alzheimer/fisiopatologia , Animais , Giro Denteado/efeitos dos fármacos , Giro Denteado/patologia , Proteína 4 Homóloga a Disks-Large/metabolismo , Antagonistas de Aminoácidos Excitatórios/farmacologia , Proteína Glial Fibrilar Ácida/metabolismo , Ácido Glutâmico/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Antígeno Ki-67/metabolismo , Masculino , Memantina/farmacologia , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos , Ratos Wistar , Receptores de Glutamato Metabotrópico/metabolismo , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/metabolismo
10.
J Neurosci Methods ; 345: 108890, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32768413

RESUMO

BACKGROUND: Nature and size of rodent cages vary from one laboratory or country to another. Little is however known about the physiological implications of exposure to diverse cage sizes in animal-based experiments. METHOD: Here, two groups of male Swiss mice (Control group - Cage stationed, and Test group - Cage migrated) were used for this study. The cage-migrated mice were exposed daily to various cage sizes used across laboratories in Nigeria while the cage-stationed mice exposed daily to different but the same cage size and shape. At the end of the 30 days exposure, top-rated paradigms were used to profile changes in physiological behaviours, and this was followed by evaluation of histological and biochemical metrics. RESULTS: The study showed a significant (p < 0.05) decrease in blood glucose levels (at 60 and 120 min of oral glucose tolerance test) in the cage-migrated mice compared to cage-stationed mice. Strikingly, peripheral oxidative stress (plasma malondialdehyde) and pain sensitivity (formalin test, hot-and-cold plate test, and von Frey test) decreased significantly in cage-migrated mice compared to cage-stationed animals. Also, the pro-inflammation mediators (IL-6 and NF-κB) increased significantly in cage-migrated mice compared to cage-stationed mice. However, emotion-linked behaviours, neurotransmitters (serotonin, noradrenaline and GABA), brain and plasma electrolytes were not significantly difference in cage-migrated animals compared to cage-stationed mice. CONCLUSION: Taken together, these results suggest that varied size cage-to-cage exposure of experimental mice could affect targeted behavioural and biomolecular parameters of pain and inflammation, thus diminishing research reproducibility, precipitating false negative/positive results and leading to poor translational outcomes.


Assuntos
Limiar da Dor , Dor , Animais , Biomarcadores , Abrigo para Animais , Inflamação/induzido quimicamente , Masculino , Camundongos , Reprodutibilidade dos Testes
11.
Anatomy & Cell Biology ; : 342-354, 2020.
Artigo | WPRIM (Pacífico Ocidental) | ID: wpr-830250

RESUMO

Cymbopogon citratus is a tropical phytomedicinal plant that is widely known for its hypoglycemic, hypolipidemic, anxiolytic, sedative, antioxidative and anti-inflammatory properties. In this study, we have examined the neuroprotective effects of the essential oil (ESO) of Cymbopogon citratus, following aluminum chloride (AlCl3)-induced neurotoxicity within the cerebellum of Wistar rats. A total of 40 adult male Wistar rats were assigned into five groups and treated orally as follows: A–phosphate-buffered saline (1 ml daily for 15 days); B–ESO (50 mg/kg daily for 15 days); C–AlCl3 (100 mg/kg daily for 15 days); D–AlCl3 then ESO (100 mg/kg AlCl3 daily for 15 days followed by 50 mg/kg ESO daily for subsequent 15 days); E– ESO then AlCl3 (50 mg/kg ESO daily for 15 days followed by 100 mg/kg AlCl3 daily for following 15 days). To address our questions, we observed the locomotion and exploratory behavior of the rats in the open field apparatus and subsequently evaluated cerebellar oxidative redox parameters, neural bioenergetics, acetylcholinesterase levels, transferrin receptor protein, and total protein profiles by biochemical assays. Furthermore, we investigated cerebellar histomorphology and Nissl profile by H&E and Cresyl violet Nissl staining procedures. ESO treatment markedly attenuated deficits in exploratory activities and rearing behavior following AlCl3 toxicity, indicating its anxiolytic potentials. Additionally, AlCl3 evokedincrease in malondialdehyde and nitric oxide levels, as well as repressed cerebellar catalase, glutathione peroxidase, and superoxide dismutase profiles were normalised to baseline levels by ESO treatment. Treatment with ESO, ergo, exhibits substantial neuroprotective and modulatory potentials in response to AlCl3 toxicity.

12.
Anatomy & Cell Biology ; : 342-354, 2020.
Artigo | WPRIM (Pacífico Ocidental) | ID: wpr-830243

RESUMO

Cymbopogon citratus is a tropical phytomedicinal plant that is widely known for its hypoglycemic, hypolipidemic, anxiolytic, sedative, antioxidative and anti-inflammatory properties. In this study, we have examined the neuroprotective effects of the essential oil (ESO) of Cymbopogon citratus, following aluminum chloride (AlCl3)-induced neurotoxicity within the cerebellum of Wistar rats. A total of 40 adult male Wistar rats were assigned into five groups and treated orally as follows: A–phosphate-buffered saline (1 ml daily for 15 days); B–ESO (50 mg/kg daily for 15 days); C–AlCl3 (100 mg/kg daily for 15 days); D–AlCl3 then ESO (100 mg/kg AlCl3 daily for 15 days followed by 50 mg/kg ESO daily for subsequent 15 days); E– ESO then AlCl3 (50 mg/kg ESO daily for 15 days followed by 100 mg/kg AlCl3 daily for following 15 days). To address our questions, we observed the locomotion and exploratory behavior of the rats in the open field apparatus and subsequently evaluated cerebellar oxidative redox parameters, neural bioenergetics, acetylcholinesterase levels, transferrin receptor protein, and total protein profiles by biochemical assays. Furthermore, we investigated cerebellar histomorphology and Nissl profile by H&E and Cresyl violet Nissl staining procedures. ESO treatment markedly attenuated deficits in exploratory activities and rearing behavior following AlCl3 toxicity, indicating its anxiolytic potentials. Additionally, AlCl3 evokedincrease in malondialdehyde and nitric oxide levels, as well as repressed cerebellar catalase, glutathione peroxidase, and superoxide dismutase profiles were normalised to baseline levels by ESO treatment. Treatment with ESO, ergo, exhibits substantial neuroprotective and modulatory potentials in response to AlCl3 toxicity.

13.
Cannabis Cannabinoid Res ; 3(1): 219-227, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30498786

RESUMO

Background: The emergence of a multidrug-resistant strain of Plasmodium falciparum (Pf Pailin) raises concern about malaria control strategies. Unfortunately, the role(s) of natural plants/remedies in curtailing malaria catastrophe remains uncertain. The claims of potential antimalarial activity of Cannabis sativa in vivo have not been well established nor the consequences defined. This study was, therefore, designed to evaluate the effects of whole cannabis consumption on malaria-infected host. Methods: Thirty mice were inoculated with dose of 1×107 chloroquine-resistant Plasmodium berghei ANKA-infected erythrocyte and divided into six treatment groups. Cannabis diet formulations were prepared based on weighted percentages of dried cannabis and standard mice diet and the study animals were fed ad libitum. Chemosuppression of parasitemia, survival rates, parasite clearance, and recrudescence time were evaluated. Histopathological studies were performed on the prefrontal cortex (PFC) and hippocampus of the animals after 14 days' consumption of cannabis diet formulation by naive mice. Results: There was a significant difference (p<0.05) in the day-4 chemosuppression of parasitemia between the animals that were fed C. sativa and chloroquine relative to the untreated controls. There was also a significant difference in the survival rate (p<0.05) of animals fed C. sativa diet (40%, 20%, 10%, and 1%) in contrast to control animals on standard mice diet. A parasite clearance time of 2.18±0.4 was recorded in the chloroquine treatment group, whereas recrudescence in chloroquine group occurred on day 7. There were slight histomorphological changes in the PFC and cell densities of the dentate gyrus of the hippocampus of animals that were fed C. sativa. Conclusions: C. sativa displayed mild antimalarial activity in vivo. There was evident reduction in symptomatic manifestation of malaria disease, though unrelated to levels of parasitemia. This disease tolerance status may be beneficial, but may also constitute a transmission burden through asymptomatic carriage of parasites by habitual cannabis users.

14.
Environ Toxicol Pharmacol ; 62: 120-131, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30005307

RESUMO

Metal ions are crucial for normal neurochemical signaling and perturbations in their homeostasis have been associated with neurodegenerative processes. Hypothesizing that in vivo modulation of key neurochemical processes including metal ion regulation (by transferrin receptor-1: TfR-1) in cells can improve disease outcome, we investigated the efficacy of a complex vitamin supplement (CVS) containing B-vitamins and ascorbic acid in preventing/reversing behavioral decline and neuropathology in rats. Wistar rats (eight weeks-old) were assigned into five groups (n = 8), including controls and those administered CVS (400 mg/kg/day) for two weeks before or after AlCl3 (100 mg/kg)-induced neurotoxicity. Following behavioral assessments, prefrontal cortex (PFC) and hippocampus were prepared for biochemical analyses, histology and histochemistry. CVS significantly reversed reduction of exploratory/working memory, frontal-dependent motor deficits, cognitive decline, memory dysfunction and anxiety. These correlated with CVS-dependent modulation of TfP-1 expression that were accompanied by significant reversal of neural oxidative stress in expressed superoxide dismutase, nitric oxide, catalase, glutathione peroxidase and malondialdehyde. Furthermore, CVS inhibited neural bioenergetics dysfunction, with increased labelling of glucokinase within PFC and hippocampus correlating with increased glucose-6-phosphate dehydrogenase and decreased lactate dehydrogenase expressions. These relates to inhibition of over-expressed acetylcholinesterase and increased total protein synthesis. Histological and Nissl staining of thin sections corroborated roles of CVS in reversing AlCl3-induced neuropathology. Summarily, we showed the role of CVS in normalizing important neurochemical molecules linking concurrent progression of oxidative stress, bioenergetics deficits, synaptic dysfunction and cellular hypertrophy during neurodegeneration.


Assuntos
Ácido Ascórbico/farmacologia , Fármacos Neuroprotetores/farmacologia , Complexo Vitamínico B/farmacologia , Vitaminas/farmacologia , Cloreto de Alumínio , Compostos de Alumínio/toxicidade , Animais , Ansiedade/tratamento farmacológico , Ansiedade/fisiopatologia , Comportamento Animal/efeitos dos fármacos , Cloretos/toxicidade , Cognição/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Síndromes Neurotóxicas/tratamento farmacológico , Síndromes Neurotóxicas/fisiopatologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiologia , Ratos Wistar
15.
Pathophysiology ; 25(1): 57-62, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29307662

RESUMO

Nicotine is a neuro-stimulant that has been implicated in the pathophysiology of many brain diseases. The need to prevent or alleviate the resulting dysfunction is therefore paramount, which has also given way to the use of medicinal plants in the management of brain conditions. This study was designed to determine the histomorphological and neurobehavioural changes in the cerebellum of Wistar rats following nicotine insult and how such injuries respond to Moringa intervention. Twenty-four adult male Wistar rats were divided into 4 groups. Group A and B were orally treated with normal saline and Moringa oleifera respectively for twenty-eight days; Group C was treated with nicotine while group D was treated orally with Moringa oleifera and intraperitoneally with nicotine for twenty-eight days. Animals were subjected to the open field test on the last day of treatment. 24 h after last day treatment, the animals were anesthetized and perfusion fixation was carried out. The cerebellum was excised and post-fixed in 4% paraformaldehyde and thereafter put through routine histological procedures. Results revealed cytoarchitectural distortion and extreme chromatolysis in neuronal cells of the cerebellar cortical layers in the nicotine-treated group. The Purkinje cells of the cerebellum of animals in this group were degenerated. There were also reduced locomotor activities in the group. Moringa was able to prevent the chromatolysis, distortion of the cerebellar cortical cells and neurobehavioural deficit. Our result suggests that Moringa oleifera could prevent nicotine-induced cerebellar injury in Wistar rats, with the possibility of ameliorating the clinical features presented in associated cerebellar pathology.

16.
Malays J Med Sci ; 25(2): 50-63, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30918455

RESUMO

BACKGROUND: This study explored the efficacy of kolaviron-a biflavonoid complex isolated from the seeds of Garcinia kola-in protecting against cuprizone (CPZ)-induced demyelination in both the prefrontal cortex and the hippocampus of Wistar rats. METHODOLOGY: Thirty rats were treated to receive 0.5 mL phosphate-buffered saline (group A, control), 0.5 mL corn oil (group B), 0.2% CPZ (group C), for 6 weeks, 0.2% CPZ for 3 weeks and then 200 mg/kg of Kv for 3 weeks (group D), or 200 mg/kg of Kv for 3 weeks followed by 0.2% CPZ for 3 weeks (group E). Rats were assessed for exploratory functions and anxiety-like behaviour before being euthanised and perfused transcardially with 4% paraformaldehyde. Prefrontal and hippocampal thin sections were stained in hematoxylin and eosin and cresyl fast violet stains. RESULTS: CPZ-induced demyelination resulted in behavioural impairment as seen by reduced exploratory activities, rearing behaviour, stretch attend posture, center square entry, and anxiogenic characteristics. Degenerative changes including pyknosis, karyorrhexis, neuronal hypertrophy, and reduced Nissl integrity were also seen. Animals treated with Kv showed significant improvement in behavioural outcomes and a comparatively normal cytoarchitectural profile. CONCLUSION: Kv provides protective roles against CPZ-induced neurotoxicity through prevention of ribosomal protein degradation.

17.
Ann Neurosci ; 24(1): 32-45, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28827919

RESUMO

BACKGROUND: Recent evidences suggest that cerebellar degeneration may be associated with the development of Alzheimer's disease (AD). However, previous reports were mainly observational, lacking substantial characterization of cellular and molecular cerebellar features during AD progression. PURPOSE: This study is aimed at characterizing the cerebellum in rat models of AD and assessing the corresponding neuroprotective mechanisms of Garcinia biflavonoid complex (GBc). METHODS: Male Wistar rats were grouped and treated alone or in combination with PBS (ad libitum)/day, corn oil (CO; 2 mL/kgBw/day), GBc (200 mg/kgBw/day), sodium azide (NaN3) (15 mg/kgBw/day) and aluminium chloride (AlCl3) (100 mg/kgBw/day). Groups A and B received PBS and CO, respectively; C received GBc; D received NaN3; E received AlCl3; F received NaN3 then GBc subsequently; G received AlCl3 then GBc subsequently; H received NaN3 and GBc simultaneously while I received AlCl3 and GBc simultaneously. Following treatments, cerebellar cortices were processed for histology, immunohistochemistry and colorimetric assays. RESULTS: Our data revealed that cryptic granule neurons and pyknotic Purkinje cell bodies (characterized by short dendritic/axonal processes) correspond to indistinctly demarcated cerebellar layers in rats treated with AlCl3 and NaN3. These correlates, with observed hypertrophic astrogliosis, increased the neurofilament deposition, depleted the antioxidant system-shown by expressed superoxide dismutase and glutathione peroxidase, and cerebellar glucose bioenergetics dysfunction-exhibited in assayed lactate dehydrogenase and glucose-6-phosphate dehydrogenase. We further showed that GBc reverses cerebellar degeneration through modulation of neurochemical signaling pathways and stressor molecules that underlie AD pathogenesis. CONCLUSION: Cellular, molecular and metabolic neurodegeneration within the cerebellum is associated with AlCl3 and NaN3-induced AD while GBc significantly inhibits corresponding neurotoxicity and is more efficacious when pre-administered.

18.
Metab Brain Dis ; 32(4): 1147-1161, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28405779

RESUMO

Earliest signs of neurodegenerative cascades in the course of Alzheimer's disease (AD) are seen within the prefrontal cortex (PFC) and hippocampus, with pathological evidences in both cortical structures correlating with manifestation of behavioural and cognitive deficits. Despite the enormous problems associated with AD's clinical manifestations in sufferers, therapeutic advances for the disorder are still very limited. Therefore, this study examined cortico-hippocampal microstructures in models of AD, and evaluated the possible beneficial roles of kolaviron (Kv)-a biflavonoid complex in rats. Nine groups of rats were orally exposed to sodium azide (NaN3) or aluminium chloride (AlCl3) solely or in different combinations with Kv. Sequel to sacrifice and transcardial perfusion (using buffered saline then 4% paraformaldehyde), PFC and hippocampal tissues were harvested and processed for: spectrophotometric assays of oxidative stress and neuronal bioenergetics parameters, histological demonstration of cytoarchitecture and immunohistochemical evaluation of astrocytes and neuronal cytoskeleton. Results showed alterations in mitochondrial functions, which led to compromised neuronal antioxidant system, dysfunctional neural bioenergetics, hypertrophic astrogliosis, cytoskeletal dysregulation and neuronal death within the PFC and hippocampus. These degenerative events were associated with NaN3 and AlCl3 toxicity in rats. Furthermore, Kv inhibited cortico-hippocampal degeneration through multiple mechanisms that primarily involved halting of biochemical cascades that activate proteases which destroy molecules expedient for cell survival, and others that mediate a program of cell suicide in neuronal apoptosis. In conclusion, Kv showed important neuroprotective roles within cortico-hippocampal cells through multiple mechanisms, and particularly has prominent prophylactic activity than regenerative potentials.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Córtex Cerebral/efeitos dos fármacos , Flavonoides/uso terapêutico , Hipocampo/efeitos dos fármacos , Degeneração Neural/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Extratos Vegetais/uso terapêutico , Cloreto de Alumínio , Compostos de Alumínio , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Morte Celular/efeitos dos fármacos , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Cloretos , Flavonoides/farmacologia , Hipocampo/metabolismo , Hipocampo/patologia , Degeneração Neural/induzido quimicamente , Degeneração Neural/metabolismo , Degeneração Neural/patologia , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Neuroglia/patologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Ratos , Azida Sódica , Superóxido Dismutase/metabolismo
19.
Environ Toxicol Pharmacol ; 50: 200-211, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28192749

RESUMO

Exploring the links between neural pathobiology and behavioural deficits in Alzheimer's disease (AD), and investigating substances with known therapeutic advantages over subcellular mechanisms underlying these dysfunctions could advance the development of potent therapeutic molecules for AD treatment. Here we investigated the efficacy of ascorbic acid (AA) in reversing aluminium chloride (AlCl3)-induced behavioural deficits and neurotoxic cascades within prefrontal cortex (PFC) and hippocampus of rats. A group of rats administered oral AlCl3 (100mg/kg) daily for 15days showed degenerative changes characterised by significant weight loss, reduced exploratory/working memory, frontal-dependent motor deficits, cognitive decline, memory dysfunction and anxiety during behavioural assessments compared to control. Subsequent analysis showed that oxidative impairment-indicated by depleted superoxide dismutase and lipid peroxidation (related to glutathione-S-transferase activity), cholinergic deficits seen by increased neural acetylcholinesterase (AChE) expression and elevated lactate dehydrogenase underlie behavioural alterations. Furthermore, evidences of proteolysis were seen by reduced Nissl profiles in neuronal axons and dendrites which correspond to apoptotic changes observed in H&E staining of PFC and hippocampal sections. Interestingly, AA (100mg/kg daily for 15days) significantly attenuated behavioural deficits in rats through inhibition of molecular and cellular stressor proteins activated by AlCl3. Our results showed that the primary mechanisms underlying AA therapeutic advantages relates closely with its abilities to scavenge free radicals, prevent membrane lipid peroxidation, modulate neuronal bioenergetics, act as AChE inhibitor and through its anti-proteolytic properties. These findings suggest that supplementing endogenous AA capacity through its pharmacological intake may inhibit progression of AD-related neurodegenerative processes and behavioural alterations.


Assuntos
Compostos de Alumínio/toxicidade , Doença de Alzheimer/tratamento farmacológico , Ansiedade/tratamento farmacológico , Ácido Ascórbico/administração & dosagem , Cloretos/toxicidade , Comportamento Exploratório/efeitos dos fármacos , Cloreto de Alumínio , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/psicologia , Animais , Ácido Ascórbico/farmacologia , Modelos Animais de Doenças , Progressão da Doença , Hipocampo/efeitos dos fármacos , Humanos , Peroxidação de Lipídeos , Córtex Pré-Frontal/efeitos dos fármacos , Ratos
20.
Malays J Med Sci ; 23(5): 17-28, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27904421

RESUMO

BACKGROUND: Cannabis is a widely used illicit drug with various threats of personality syndrome, and Nigella sativa has been widely implicated as having therapeutic efficacy in many neurological diseases. The present study investigates the ameliorative efficacy of Nigella sativa oil (NSO) on cannabis-induced moto-cognitive defects. METHODS: Scopolamine (1 mg/kg i.p.) was given to induce dementia as a standard base line for cannabis (20 mg/kg)-induced cognitive impairment, followed by an oral administration of NSO (1 ml/kg) for 14 consecutive days. The Morris water maze (MWM) paradigm was used to assess the memory index, the elevated plus maze was used for anxiety-like behaviour, and the open field test was used for locomotor activities; thereafter, the rats were sacrificed and their brains were removed for histopathologic studies. RESULTS: Cannabis-like Scopolamine caused memory impairment, delayed latency in the MWM, and anxiety-like behaviour, coupled with alterations in the cerebello-hippocampal neurons. The post-treatment of rats with NSO mitigated cannabis-induced cognitive dysfunction as with scopolamine and impaired anxiety-like behaviour by increasing open arm entry, line crossing, and histological changes. CONCLUSIONS: The observed ameliorative effects of NSO make it a promising agent against moto-cognitive dysfunction and cerebelo-hippocampal alterations induced by cannabis.

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