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1.
Animals (Basel) ; 14(6)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38540038

RESUMO

The specific arrangement and distribution of photoreceptors in the retina can vary among different fish species, with each species exhibiting adaptations related to its habitat, behavior, and visual requirements. Poecilia sphenops, a diurnal fish, was the focus of this study. The retinas of a total of eighteen Molly fish were investigated utilizing light and electron microscopy. The retina exhibited a square mosaic pattern of the inner segments of cones. This pattern comprised double cones positioned along the sides of a square, with two types of single cones situated at the center and corners of the square arrangement across the entire retina. The corner cones were slightly shorter than the central ones. Additionally, the outer plexiform layer contained both cone pedicles and rod spherules. The rod spherule consisted of a single synaptic ribbon arranged in a triad or quadrat junctional arrangement within the invaginating free ends of the horizontal and bipolar cell processes. On the other hand, cone pedicles have more than one synaptic ribbon in their junctional complex. The inner nuclear layer consisted of the amacrine, bipolar, Müller, and horizontal cell bodies. Müller cell processes, expressing GFAP, extended across all retinal layers, segmenting the deeper retina into alternating fascicles of optic axons and ganglion cells. The outer and inner plexiform layers showed many astrocyte cell processes expressing GFAP. In conclusion, the current study is the first record of the retinal structures of Molly fish. This study illustrated the mosaic arrangement of photoreceptors and GFAP expression patterns of astrocytes and Müller cells. The presence of three cone types, coupled with a sufficient number of rods, likely facilitates motion awareness for tasks like finding food and performing elaborate mating ceremonies.

2.
Inflammopharmacology ; 32(2): 1295-1315, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38512652

RESUMO

Multiple sclerosis (MS) is a chronic inflammatory neurodegenerative disease of the central nervous system that injures the myelin sheath, provoking progressive axonal degeneration and functional impairments. No efficient therapy is available at present to combat such insults, and hence, novel safe and effective alternatives for MS therapy are extremely required. Rutin (RUT) is a flavonoid that exhibits antioxidant, anti-inflammatory, and neuroprotective effects in several brain injuries. The present study evaluated the potential beneficial effects of two doses of RUT in a model of pattern-III lesion of MS, in comparison to the conventional standard drug; dimethyl fumarate (DMF). Demyelination was induced in in male adult C57BL/6 mice by dietary 0.2% (w/w) cuprizone (CPZ) feeding for 6 consecutive weeks. Treated groups received either oral RUT (50 or 100 mg/kg) or DMF (15 mg/kg), along with CPZ feeding, for 6 consecutive weeks. Mice were then tested for behavioral changes, followed by biochemical analyses and histological examinations of the corpus callosum (CC). Results revealed that CPZ caused motor dysfunction, demyelination, and glial activation in demyelinated lesions, as well as significant oxidative stress, and proinflammatory cytokine elevation. Six weeks of RUT treatment significantly improved locomotor activity and motor coordination. Moreover, RUT considerably improved remyelination in the CC of CPZ + RUT-treated mice, as revealed by luxol fast blue staining and transmission electron microscopy. Rutin also significantly attenuated CPZ-induced oxidative stress and inflammation in the CC of tested animals. The effect of RUT100 was obviously more marked than either that of DMF, regarding most of the tested parameters, or even its smaller tested dose. In silico docking revealed that RUT binds tightly within NF-κB at the binding site of the protein-DNA complex, with a good negative score of -6.79 kcal/mol. Also, RUT-Kelch-like ECH-associated protein 1 (Keap1) model clarifies the possible inhibition of Keap1-Nrf2 protein-protein interaction. Findings of the current study provide evidence for the protective effect of RUT in CPZ-induced demyelination and behavioral dysfunction in mice, possibly by modulating NF-κB and Nrf2 signaling pathways. The present study may be one of the first to indicate a pro-remyelinating effect for RUT, which might represent a potential additive benefit in treating MS.


Assuntos
Doenças Desmielinizantes , Esclerose Múltipla , Doenças Neurodegenerativas , Fármacos Neuroprotetores , Masculino , Animais , Camundongos , Esclerose Múltipla/induzido quimicamente , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/metabolismo , Cuprizona/efeitos adversos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/tratamento farmacológico , Doenças Desmielinizantes/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , NF-kappa B/metabolismo , Rutina/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
3.
BMC Vet Res ; 19(1): 34, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36737791

RESUMO

BACKGROUND: The Japanese quail is considered one of the most significant species in the poultry industry. However, the high male-to-female ratio results in the aggressive behavior of males. Dietary strategies that improve the properties of semen could reduce the number of males required to maintain optimal fertility and reduce aggressive behavior. Therefore, this study aims to provide insight into the possible improving efm fect of ginger roots on the reproductive aspects of Japanese male quails. RESULTS: To achieve this objective, powder of Ginger roots was administrated to 2 groups of quails (10, and 15 g/Kg feed) from 7 days until 70 days of age. Some males were reared singly in cages (n = 40 for each group) to assess sperm quality and other males (n = 32 for each group) were raised with females to assess fertility and sperm-egg penetration. Additionally, biochemical tests and histological examination were also performed. When compared to the control group, dietary inclusion of Ginger at a dose of 15 g caused more improvement in ejaculate volume, sperm concentration, motility, viability and sperm-egg penetration. Whereas, the motility and fertility percentages of sperms were equipotent in both doses. Dose-dependent increases were found in the cloacal gland area and volume, as well as foam production and weight. Both doses resulted in a significant reduction in plasma total cholesterol along with an elevation cin plasma testosterone and lipid peroxides. The comparison between all groups concerning nitric oxide, catalase, superoxide dismutase, and total antioxidant capacity revealed the absence of significant difference. Morphologically, the diameter of the seminiferous tubules and the height of germinal epithelium significantly increased especially in the higher dose of Ginger. CONCLUSIONS: Ginger roots especially at a dose of 15 gm/kg feed was effective in improving male reproductive performance. These findings are of utmost importance in encouraging the addition of Ginger roots in ration formulation in male quails.


Assuntos
Coturnix , Zingiber officinale , Masculino , Feminino , Animais , Sementes , Reprodução , Fertilidade
4.
Sci Rep ; 12(1): 16970, 2022 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-36216854

RESUMO

Alzheimer's disease is among the challenging diseases to social and healthcare systems because no treatment has been achieved yet. Although the ambiguous pathological mechanism underlying this disorder, ion channel dysfunction is one of the recently accepted possible mechanism. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels play important roles in cellular excitability and synaptic transmission. Ivabradine (Iva), an HCN blocker, is acting on HCN channels, and is clinically used for angina and arrhythmia. The current study aimed to investigate the therapeutic effects of Iva against scopolamine (Sco) induced dementia. To test our hypothesis, Sco and Iva injected rats were tested for behavioural changes, followed by ELISA and histopathological analysis of the hippocampus. Induced dementia was confirmed by behavioural tests, inflammatory cytokines and oxidative stress tests and histopathological signs of neurodegeneration, multifocal deposition of congo red stained amyloid beta plaques and the decreased optical density of HCN1 immunoreactivity. Iva ameliorated the scopolamine-induced dysfunction, the hippocampus restored its normal healthy neurons, the amyloid plaques disappeared and the optical density of HCN1 immunoreactivity increased in hippocampal cells. The results suggested that blockage of HCN1 channels might underly the Iva therapeutic effect. Therefore, Iva might have beneficial effects on neurological disorders linked to HCN channelopathies.


Assuntos
Demência , Canais de Potássio , Peptídeos beta-Amiloides , Animais , Cognição , Vermelho Congo , Canais de Cátion Regulados por Nucleotídeos Cíclicos , Citocinas , Demência/induzido quimicamente , Demência/tratamento farmacológico , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização , Ivabradina/farmacologia , Nucleotídeos Cíclicos , Ratos , Escopolamina
5.
J Egypt Natl Canc Inst ; 34(1): 37, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36058937

RESUMO

BACKGROUND: About 7 million people die from various types of cancer every year representing nearly 12.5% of deaths worldwide. This fact raises the demand to develop new, effective anticancer, onco-suppressive, and chemoprotective agents for the future fighting of cancers. Genistein exhibits pleiotropic functions in cancer, metabolism, and inflammation. It functions as an antineoplastic agent through its effect on the cell cycle, apoptotic processes, angiogenesis, invasion, and metastasis. AIM OF THE STUDY: The current study aimed to study the genistein onco-suppressive effects during 7,12-dimethylbenz[a]anthracene (DMBA)-induced oral carcinogenesis in hamsters' buccal pouch utilizing flow cytometry analysis (FMA), as a fast-diagnosing tool, in addition to the histopathology. MATERIAL AND METHODS: The buccal mucosa of adult male Syrian hamsters was painted with paraffin oil only (group 1), DMBA mixed in mineral oil (group 2), or orally administrated genistein along with painting DMBA (group 2B). The buccal mucosa was utilized for flow cytometric analysis and histopathological examination. RESULTS: Grossly, DMBA-induced carcinogenesis started at the 9th week. Progressive signs appeared in the following weeks reaching to large ulcerative oral masses and exophytic nodules at the 21st week. Histologically, invasive well-differentiated oral squamous cell carcinoma (OSCC) appeared in the underlying tissues from the 12th week, showing malignant criteria. Genistein had delayed clinicopathological change, which started 6 weeks later, than the DMBA-painted hamsters, as mild epithelial dysplastic changes. This became moderate during the last 6 weeks, without dysplastic changes. Flow cytometry revealed that DMBA led to considerable variation in DNA proliferation activity, aneuploid DNA pattern, in 47.22% of hamsters and significantly raised the S-phase fragment (SPF) values, which drastically reduced after genistein treatment. CONCLUSION: Taken together, genistein could be employed as an onco-suppressive agent for carcinogenesis. Moreover, FMA could be used as an aiding fast tool for diagnosis of cancer.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Animais , Carcinogênese/patologia , Carcinoma de Células Escamosas/induzido quimicamente , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Cricetinae , Genisteína/efeitos adversos , Humanos , Masculino , Mesocricetus , Neoplasias Bucais/induzido quimicamente , Neoplasias Bucais/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço
6.
Microsc Microanal ; : 1-14, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35513852

RESUMO

The donkey is mainly used as a working animal for riding and pack transport, as well as for dairy and meat production. Eye afflictions are common in donkeys, thus requiring a detailed study. A few studies had focused on the donkey's eye, and most of them had considered it, merely, a horse's eye. This study aimed to investigate the anatomy, histology, ultrastructure, and immunohistochemical features of the donkey's eye. The results were recorded and compared to those of horses in certain dimensions. Unlike horses, the donkey's eye is more circular in the contour of the cornea, has smaller lenticular thickness, and has longer anterior and vitreous chambers. Positive immunoreactivity to acidic fibroblast growth factor in the basal cell layers of the cornea was observed, indicating their role in cell differentiation and the renewal of the epithelium. Moreover, the corneal keratocytes expressed angiotensin-converting enzyme, which plays a role in corneal homeostasis and wound healing. Additionally, telocytes, hyalocytes, and other immune cells were observed within the iris and ciliary processes. Hence, this work is an updated detailed study of the morphology and ultrastructure of the donkey's eye and reveals some similarities and dissimilarities to the horse's eyes, which should be considered in clinical practice.

7.
Biol Trace Elem Res ; 200(4): 1688-1698, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34110565

RESUMO

The increase in the usage of silica nanoparticles (SiNPs) in the industrial and medical fields has raised concerns about their possible adverse effects on human health. The present study aimed to investigate the potential adverse effects of SiNPs at daily doses of 25 and 100 mg/kg body weight intraperitoneally (i.p.) for 28 consecutive days on markers of liver damage in adult male rats. Results revealed that SiNPs induced a marked increase in serum markers of liver damage, including lactate dehydrogenase (LDH), alanine aminotransferase (ALAT), and aspartate aminotransferase (ASAT). SiNPs also induced an elevation of reactive oxygen species (ROS) production in liver, along with an increase in oxidative stress markers (NO, MDA, PCO, and H2O2), and a decrease in antioxidant enzyme activities (CAT, SOD, and GPx). Quantitative real-time PCR showed that SiNPs also induced upregulation of pro-apoptotic gene expression (including Bax, p53, Caspase-9/3) and downregulation of anti-apoptotic factors Bcl-2. Moreover, histopathological analysis revealed that SiNPs induced hepatocyte alterations, which was accompanied by sinusoidal dilatation, Kupffer cell hyperplasia, and the presence of inflammatory cells in the liver. Taken together, these data showed that SiNPs trigger hepatic damage through ROS-activated caspase signaling pathway, which plays a fundamental role in SiNP-induced apoptosis in the liver.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Nanopartículas , Animais , Apoptose , Peróxido de Hidrogênio/farmacologia , Masculino , Nanopartículas/toxicidade , Estresse Oxidativo , Ratos , Transdução de Sinais , Dióxido de Silício/toxicidade , Proteína X Associada a bcl-2/genética
8.
Gene Expr Patterns ; 42: 119217, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34767969

RESUMO

Midbrain dopaminergic neurons (mDA) play an important role in controlling the voluntary motor movement, reward, and emotion-based behaviour. Differentiation of mDA neurons from progenitors depends on several secreted proteins, such as sonic hedgehog (SHH). The present study attempted to elucidate the possible role(s) of some SHH signaling components (Ptch1, Gli1, Gli2 and Gli3) in the spatiotemporal development of mDA neurons along the rostrocaudal axis of the midbrain and their possible roles in differentiation and survival of mDA neurons and the significance of using in vitro models for studying the development of mDA neurons. At E12 and E14, only Ptch1 and Gli1 were expressed in ventrolateral midbrain domains. All examined SHH signalling molecules were not detected in mDA area. Whereas, in MN9D cells, many SHH signalling molecules were expressed and co-localized with the dopaminergic marker; tyrosine hydroxylase (TH), and their expression were upregulated with SHH treatment of the MN9D cells. These results suggest that mDA neurons differentiation and survival might be independent of SHH in the late developmental stages (E12-18). Besides, MN9D cell line is not the ideal in vitro model for investigating the differentiation of mDA and hence, the ventral midbrain primary culture might be favored over MN9D line.


Assuntos
Neurônios Dopaminérgicos , Proteínas Hedgehog , Animais , Diferenciação Celular , Neurônios Dopaminérgicos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Mesencéfalo/metabolismo , Camundongos , Neurogênese
9.
Microsc Microanal ; : 1-14, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34344492

RESUMO

The current study investigated the morphological, histochemical, and immunohistochemical characteristics of alarm cells and their precursors in ruby-red-fin shark (rainbow shark), Epalzeorhynchos frenatum (Teleostei: Cyprinidae). Precursor alarm cells were shown to be small, cuboidal, pyramidal, or round in shape, with eosinophilic cytoplasm, resting on the basement membrane of the epidermis. The cells later elongated to become columnar in shape. Subsequently, they enlarged and became large oval-shaped cells. They then underwent shrinkage and vacuolation. The superficial alarm cells were collapsed. Alarm cells were found to have an affinity for different histochemical stains, including bromophenol blue, iron hematoxylin, Sudan black, Mallory triple trichrome, Crossman's trichrome, Safranin O, and Weigert's stains, as well as lipase and alkaline phosphatase. Endocrine properties of the alarm cells were identified by silver staining and synaptophysin immunostaining. Alarm cells exhibited stemness activities and had a strong immunoaffinity for CD117. They had a proteolytic function, as identified by lysosome-specific staining with acridine orange and strong immunoaffinity for matrix metalloproteinase (MMP-9). They also exhibited proliferatively, reflected by immunological staining by proliferating cell nuclear antigen. In conclusion, alarm cells are unique epidermal cells with multiple functions. They play immunological, and endocrine, roles. They also retain stemness and proliferative properties.

10.
NanoImpact ; 24: 100358, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-35559817

RESUMO

Increasing environmental exposure to silica nanoparticles (SiNPs) and limited neurotoxicity studies pose a challenge for safety evaluation and management of these materials. This study aimed to explore the adverse effects and underlying mechanisms of subacute exposure to SiNPs by the intraperitoneal route on hippocampus function in rats. Data showed that SiNPs induced a significant increase in oxidative/nitrosative stress markers including reactive oxygen species (ROS), malondialdehyde (MDA), protein oxidation (PCO) and nitrite (NO) production accompanied by reduced antioxidant enzyme activity (catalase, superoxide dismutase, and glutathione peroxidase) and decreased glutathione (GSH). Phenotypically, SiNPs exhibited spatial learning and memory impairment in the Morris water maze (MWM) test, a decrease of the discrimination index in the novel object recognition test (NORT) and higher anxiety-like behavior. SiNPs affected the cholinergic system as reflected by reduced acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activity. In addition, SiNPs significantly increased mRNA expression level of genes related to inflammation (TNF-α, IL-1ß, IL-6, and COX-2) and decreased mRNA expression level of genes related to cholinergic system including choline acetyltransferase (ChAT), vesicular acetylcholine transporter (VAChT), AChE, muscarinic acetylcholine receptor M1 (m1AChR) and nicotinic acetylcholine receptors (nAChR). Histopathological results further showed an alteration in the hippocampus of treated animals associated with marked vacuolation in different hippocampus areas. These findings provide new insights into the molecular mechanism of SiNPs-induced hippocampal alterations leading to impairment of cognitive and behavioral functions, and implicating oxidative stress and inflammation in the hippocampus, as well as disruption of cholinergic system.


Assuntos
Acetilcolinesterase , Nanopartículas , Acetilcolinesterase/metabolismo , Animais , Antioxidantes/metabolismo , Butirilcolinesterase/metabolismo , Colinérgicos/metabolismo , Hipocampo , Inflamação/induzido quimicamente , Nanopartículas/toxicidade , Estresse Oxidativo , RNA Mensageiro/metabolismo , Ratos , Dióxido de Silício/toxicidade
11.
Sci Rep ; 10(1): 21157, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33273572

RESUMO

Studying the cerebella of different animals is important to expand the knowledge about the cerebellum. Studying the camel cerebellum was neglected even though the recent research in the middle east and Asia. Therefore, the present study was designed to achieve a detailed description of the morphology and the cellular organization of the camel cerebellum. Because of the high importance of the calcium ions as a necessary moderator the current work also aimed to investigate the distribution of calcium binding proteins (CaBP) such as calbindin D-28K (CB), parvalbumin (PV) and calretinin (CR) in different cerebellar cells including the non-traditional neurons. The architecture of camel cerebellum, as different mammals, consists of the medulla and three layered-cortex. According to our observation the cells in the granular layer were not crowded and many spaces were observed. CB expression was the highest by Purkinje cells including their dendritic arborization. In addition to its expression by the inhibitory interneurons (basket, stellate and Golgi neurons), it is also expressed by the excitatory granule cells. PV was expressed by Purkinje cells, including their primary arborization, and by the molecular layer cells. CR immunoreactivity (-ir) was obvious in almost all cell layers with varying degrees, however a weak or any expression by the Purkinje cells. The molecular layer cells and the Golgi and the non traditional large neurons of the granular layer showed the strongest CR-ir. Granule neurons showed moderate immunoreactivity for CB and CR. In conclusion, the results of the current study achieved a complete map for the neurochemical organization of CaBP expression and distribution by different cells in the camel cerebellum.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Camelus/metabolismo , Cerebelo/metabolismo , Animais , Calbindina 2/metabolismo , Cerebelo/anatomia & histologia , Neurônios/metabolismo , Parvalbuminas/metabolismo , Células de Purkinje/metabolismo
12.
Front Cell Neurosci ; 14: 66, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32296307

RESUMO

Microglia are constantly surveying their microenvironment and rapidly react to impairments by changing their morphology, migrating toward stimuli and adopting gene expression profiles characterizing their activated state. The increased expression of the M2-like marker Mannose receptor 1 (Mrc1), which is also referred to as CD206, in microglia has been reported after M2-like activation in vitro and in vivo. Mrc1 is a 175-kDa transmembrane pattern recognition receptor which binds a variety of carbohydrates and is involved in the pinocytosis and the phagocytosis of immune cells, including microglia, and thought to contribute to a neuroprotective microglial phenotype. Here we analyzed the effects of TGFß signaling on Mrc1 expression in microglia in vivo and in vitro. Using C57BL/6 wild type and Cx3cr1 CreERT2 :R26-YFP:Tgfbr2 fl/fl mice-derived microglia, we show that the silencing of TGFß signaling results in the upregulation of Mrc1, whereas recombinant TGFß1 induced the delayed downregulation of Mrc1. Furthermore, chromatin immunoprecipitation experiments provided evidence that Mrc1 is not a direct Smad2/Smad4 target gene in microglia. Altogether our data indicate that the changes in Mrc1 expression after the activation or the silencing of microglial TGFß signaling are likely to be mediated by modifications of the secondary intracellular signaling events influenced by TGFß signaling.

13.
Microsc Microanal ; 25(4): 1052-1060, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31210121

RESUMO

The key role of the epididymis is contributing to sperm storage, maturation, and survival. The epididymis of camel has a unique structure called the intraepithelial gland. The present work aimed to investigate the structure of the epididymal intraepithelial gland with special references to the seasonal variation. The samples were collected from the distal part of the corpus epididymes of completely healthy mature camels (Camelus dromedarius) in the breeding and nonbreeding seasons. Tomato lectin-positive material had been demonstrated within the epididymal spermatozoa. Here, we provide the first transmission electron microscopic study for the intraepithelial gland of camel epididymis detecting the autophagy during the nonbreeding season. The autophagosomes originated from the endoplasmic reticulum, surrounding mitochondria, and located mainly next to the basement membrane. This location is probably valuable for subsequent passing of their contents into the interstitium for possible recycling. The histochemical and ultrastructural characteristics of the gland in the breeding season indicated a hyperactive secretory microenvironment enriched with the glycoprotein-producing machinery, which could be controlled by androgens. The present data suggest that the camel intraepithelial gland has a significant impact on the reproductive activity through their secretory microenvironment during the breeding season. Moreover, it recycles the unused organelles or proteins for reuse or to supply energy under stress conditions in the nonbreeding season.


Assuntos
Autofagossomos/ultraestrutura , Camelus , Epididimo/anatomia & histologia , Animais , Autofagossomos/metabolismo , Epididimo/fisiologia , Histocitoquímica , Masculino , Microscopia Eletrônica de Transmissão , Estações do Ano
14.
Neurochem Int ; 120: 121-133, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30102949

RESUMO

Exposure to synthetic pyrethroid (SPs) pesticides such as bifenthrin (BF) has been associated with adverse neurodevelopmental outcomes and cognitive impairments, but the underlying neurobiological mechanism is poorly understood so far. The present study has been designed to evaluate changes in behavior and in biomarkers of oxidative stress and neuroinflammation in the hippocampus of rats subchronically treated with BF. Rats exposed daily to BF at doses of 0.6 and 2.1 mg/kg b. w. for 60 days exhibited spatial and cognitive impairments as well as memory dysfunction after 60 days. This repeated BF treatment also significantly increased mRNA expression of pro-inflammatory cytokines tumor necrosis factor (TNF-α), interleukin (IL-1ß), (IL-6), nuclear factor erythroid-2 (Nrf2), cyclooxygenase-2 (COX-2), nuclear factor-kappaB pathway (NF-kappaB), and prostaglandin E2 (PGE2) in the hippocampus. It further resulted in a significant increase in protein levels of Nrf2, COX-2, microsomal prostaglandin synthase-1 (mPGES-1) and NF-kappaB. This was accompanied by oxidative/nitrosative stress in the hippocampus of treated rats, as shown by increased levels of malondialdehyde (MDA), protein carbonyls (PCO), and nitric oxide (NO), and reduced levels of enzymatic (catalase, superoxide dismutase, and glutathione peroxidase) and non-enzymatic (reduced glutathione) antioxidants. The data are in line with those obtained in organotypic hippocampal slice cultures (OHSCs) isolated from mouse brain and exposed to BF for 72 h, showing neuronal death only at the high dose of 20 µM when compared to controls. These findings suggest that exposure to BF induces neuronal damage, alters redox state, and causes neuroinflammation in the hippocampus, which might lead to cognitive and memory impairment.


Assuntos
Hipocampo/efeitos dos fármacos , Inflamação/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Piretrinas/farmacologia , Animais , Biomarcadores/metabolismo , Cognição/efeitos dos fármacos , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/metabolismo , Hipocampo/metabolismo , Inflamação/metabolismo , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/metabolismo , Ratos Wistar
15.
Int J Mol Sci ; 19(3)2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29494550

RESUMO

Microglia are the resident immune cells of the central nervous system (CNS) and participate in physiological and pathological processes. Their unique developmental nature suggests age-dependent structural and functional impairments that might contribute to neurodegenerative diseases. In the present study, we addressed the age-dependent changes in cortical microglia gene expression patterns and the expression of M1- and M2-like activation markers. Iba1 immunohistochemistry, isolation of cortical microglia followed by fluorescence-activated cell sorting and RNA isolation to analyze transcriptional changes in aged cortical microglia was performed. We provide evidence that aging is associated with decreased numbers of cortical microglia and the establishment of a distinct microglia activation profile including upregulation of Ifi204, Lilrb4, Arhgap, Oas1a, Cd244 and Ildr2. Moreover, flow cytometry revealed that aged cortical microglia express increased levels of Cd206 and Cd36. The data presented in the current study indicate that aged mouse cortical microglia adopt a distinct activation profile, which suggests immunosuppressive and immuno-tolerogenic functions.


Assuntos
Córtex Cerebral/citologia , Córtex Cerebral/imunologia , Tolerância Imunológica , Microglia/imunologia , Microglia/metabolismo , Fatores Etários , Envelhecimento/imunologia , Animais , Biomarcadores , Córtex Cerebral/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Masculino , Camundongos , Transcriptoma
16.
Glia ; 66(8): 1695-1708, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29575117

RESUMO

Microglia are involved in a widespread set of physiological and pathological processes and further play important roles during neurodevelopmental events. Postnatal maturation of microglia has been associated with the establishment of microglia-specific gene expression patterns. The mechanisms governing microglia maturation are only partially understood but Tgfß1 has been suggested to be one important mediator. In the present study, we demonstrate that early postnatal microglia maturation is associated with alternative microglia activation, increased engulfment of apoptotic cells as well as activated microglial Tgfß signaling. Interestingly, microglial Tgfß signaling preceded the induction of the microglia-specific gene expression indicating the importance of Tgfß1 for postnatal microglia maturation. Moreover, we provide evidence that Tgfß1 is expressed by neurons in postnatal and adult brains defining neuron-microglia communication via Tgfß1 as an important event. Finally, we introduce the recently identified microglia marker Tmem119 as a direct Tgfß1-Smad2 target gene. Taken together, the data presented here further increase the understanding of Tgfß1-mediated effects in microglia and place emphasis on the importance of Tgfß1 for microglia maturation and maintenance.


Assuntos
Encéfalo/metabolismo , Microglia/metabolismo , Neurônios/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Animais Recém-Nascidos , Macrófagos/metabolismo , Camundongos Knockout , Transdução de Sinais/efeitos dos fármacos
17.
Int J Mol Sci ; 17(2)2016 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-26821015

RESUMO

Parkinson's disease (PD) is a neurodegenerative disease characterised by histopathological and biochemical manifestations such as loss of midbrain dopaminergic (DA) neurons and decrease in dopamine levels accompanied by a concomitant neuroinflammatory response in the affected brain regions. Over the past decades, the use of toxin-based animal models has been crucial to elucidate disease pathophysiology, and to develop therapeutic approaches aimed to alleviate its motor symptoms. Analyses of transgenic mice deficient for cytokines, chemokine as well as neurotrophic factors and their respective receptors in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of PD have broadened the current knowledge of neuroinflammation and neurotrophic support. Here, we provide a comprehensive review that summarises the contribution of microglia-mediated neuroinflammation in MPTP-induced neurodegeneration. Moreover, we highlight the contribution of neurotrophic factors as endogenous and/or exogenous molecules to slow the progression of midbrain dopaminergic (mDA) neurons and further discuss the potential of combined therapeutic approaches employing neuroinflammation modifying agents and neurotrophic factors.


Assuntos
Modelos Animais de Doenças , Intoxicação por MPTP/imunologia , Microglia/patologia , Fatores de Crescimento Neural/metabolismo , Doença de Parkinson/imunologia , Animais , Humanos , Intoxicação por MPTP/tratamento farmacológico , Intoxicação por MPTP/patologia , Camundongos , Camundongos Transgênicos , Microglia/imunologia , Fatores de Crescimento Neural/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/etiologia , Doença de Parkinson/patologia , Receptores de Fator de Crescimento Neural/metabolismo
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