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1.
Biology (Basel) ; 12(7)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37508337

RESUMO

Alzheimer's disease (AD) is the most common cause of age-related neurodegeneration and cognitive decline. AD more commonly occurs in females than in males, so it is necessary to consider new treatments specifically targeting this population. The present study investigated the protective effects of Begacestat (γ-secretase inhibitor-953, GSI-953) and bone marrow-derived mesenchymal stem cells (BM-MSCs) during pregnancy on cognitive impairment in rat dams and neurodegeneration in offspring caused by the intracerebroventricular injection of Aß 25-35 before pregnancy. The performances of dams injected with amyloid-ß 25-35 (Aß 25-35) during behavioral tests were significantly impaired. The offspring of Aß 25-35-injected dams treated with BM-MSCs or GSI-953 showed a dramatically reduced number and size of activated microglial cells, enhancement in the processes length, and a decrease in the proinflammatory cytokine levels. Additionally, BM-MSC or GSI-953 therapy reduced Aß 25-35-induced increases in tau phosphorylation and amyloid precursor protein levels in the neonates' hippocampus and elevated the lower levels of glycogen synthase kinase-3 and brain-derived neurotrophic factor; moreover, reversed Aß 25-35-induced alterations in gene expression in the neonatal hippocampus. Finally, the treatments with BM-MSC or GSI-953 are globally beneficial against Aß 25-35-induced brain alterations, particularly by suppressing neural inflammation, inhibiting microglial cell activation, restoring developmental plasticity, and increasing neurotrophic signaling.

2.
Stem Cells Int ; 2023: 2690949, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37274020

RESUMO

Alzheimer's disease (AD) is the most frequent cause of age-related neurodegeneration and ensuing cognitive impairment. Progressive deposition of extracellular amyloid beta (Aß) aggregates (plaques) and intracellular hyperphosphorylated Tau protein (p-Tau) are the core pathological markers of AD but may precede clinical symptoms by many years, presenting a therapeutic window of opportunity. Females are more frequently afflicted by AD than males, necessitating evaluation of novel treatments for the female population. The current study examined the protective efficacies of intravenous bone marrow-derived mesenchymal stem cells (BM-MSCs) and oral gamma-secretase inhibitor-953 (GSI-953) during pregnancy on cognitive impairment in rat dams and neurodegeneration in offspring induced by intracerebroventricular injection of Aß25-35 prior to pregnancy. The Aß25-35 (AD) group exhibited significant (P < 0.001) impairments in the Y-maze and novel object recognition test performance prior to conception. Histological analysis of the offspring cortex revealed substantial dendritic shrinkage and activation of microglial cells, while neurochemical analysis demonstrated significant increases in the proinflammatory cytokine interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α). In contrast, BM-MSC or GSI-953 treatment of dams following Aß25-35 injection significantly (P < 0.001) reduced the number and size of activated microglial cells, markedly increased dendrite length, and reversed proinflammatory cytokine elevations in offspring. Moreover, BM-MSC or GSI-953 treatment reversed the Aß25-35-induced amyloid precursor protein and p-Tau elevations in the offspring brain; these changes were accompanied by upregulation of the brain-derived neurotrophic factor and downregulation of glycogen synthase kinase-3ß in the serum and brain. Treatment with BM-MSCs or GSI-953 also reversed Aß25-35-induced elevations in different gene expressions in the neonatal cortex. Finally, treatment of dams with BM-MSCs or GSI-953 prevented the Aß25-35-induced disruption of newborn brain development. Thus, BM-MSC and GSI-953 treatments have broad-spectrum effects against Aß25-35-induced brain pathology, including the suppression of neural inflammation, restoration of developmental plasticity, and promotion of neurotrophic signaling.

3.
Biomed Rep ; 16(3): 15, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35222999

RESUMO

The demand for L-asparaginase is predicted to increase several fold in the future due to its potential clinical applications in the treatment of lymphoid system malignancies and leukemia. Thus identifying suitable sources of production should be considered high priority. Fungi are valuable organisms as they are able to convert what would be considered 'useless' materials into materials that have potential value. The present study provides a proof of concept of production of a new hyperactive L-asparaginase producer (Rhizopus oryzae AM16), which was successfully isolated and sequentially optimized using a semi solid-state fermentation method with a simple and cheap medium produced from wheat bran (WB). The fungus was able to produce an appreciable amount of the enzyme (2,875.9 U) after 8 days of incubation under 85.7% moisture, in the presence of magnesium nitrate (5.0 mg N/mg nitrogen per gram of dry WB) at pH 5.8. Testing the anticancer activity confirmed the ability of the resultant enzyme to inhibit the growth of various types of cancer cells (HepG2, MCF-7, HCT and A549). The IC50 values of the dialyzed enzyme were lower than that of the crude product. Thus, this newly identified and purified L-asparaginase may be a promising anticancer drug.

4.
Saudi J Biol Sci ; 26(3): 503-513, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30899165

RESUMO

This study investigates the amphisbaenian species skull which includes cranium, lower jaw and hyoid apparatus. The medial dorsal bones comprise the premaxilla, nasal, frontal and parietal. The premaxilla carries a large medial tooth and two lateral ones. The nasals are paired bones and separated by longitudinal suture. Bones of circumorbital series are frontal, orbitosphenoid and maxilla. The occipital ring consists of basioccipital, supraoccipital and exooccipital. Supraoccipital and basioccipital are single bones while the exo-occipitals are paired. The bones of the palate comprise premaxilla, maxilla, septomaxilla, palatine, pterygoid, ectopterygoid, basisphenoid, parasphenoid, orbitosphenoid and laterosphenoid. Prevomer and pterygoid teeth are absent. Palatine represent by two separate bones. The temporal bones are clearly visible. The lower jaw consists of the dentary, articular, coronoid, supra-angular, angular and splenial. The hyoid apparatus is represented by a Y-shaped structure. The mandible is long and is suspended from the braincase via relatively short quadrate. There is an extensive contact between the long angular and the large triangular coronoid. Thus inter-mandibular joint is bridged completely by the angular and consequently, the lower jaws are relatively rigid and kinetic. The maxillae are suspended from the braincase largely by ligaments and muscles rather than through bony articulation. In conclusion, the skull shape affects feeding strategy in Diplometopon zarudnyi. The prey is ingested and transported via a rapid maxillary raking mechanism.

5.
Saudi J Biol Sci ; 26(1): 129-136, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30622416

RESUMO

In the present study, it was hypothesized that micromorphology of the surface of many lizard scales appears to mimic the topography of the habitat in which they live. Many authors have suggested that the microstructure of the superficial surface of scales have undergone important adaptations and have functional value in lizards. In this study, we investigated the variation and adaptation of the micromorphology and microstructure of the superficial surface of the dorsal and ventral scales from the mid-body region of Stellagama stellio (Agamidae), Stenodactylus petrii (Gekkonidae), Acanthodactylus boskianus (Lacertidae), Eumeces schneideri (Scincidae), Trachylepis quinquetaeniata (Scincidae), Scincus scincus (Scincidae), Varanus griseus (Varanidae), Chameleo chameleon (Chamaeleonidae). Skin specimens were prepared and analyzed using scanning electron microscopy. The dorsal and ventral scale surfaces had microstructure in the studied species and they exhibited unique patterns that somewhat resembled the topography of the microhabitats in which they lived. Similarity was detected in the three most related species, those having a common family, Scincidae. Ecomorphological relationships were detected between the dorsal and ventral scale microstructures and microhabitats. We conclude that environmental factors have observable influences on the microstructure of lizard scales.

6.
Anat Rec (Hoboken) ; 299(7): 979-89, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27111253

RESUMO

The skin of limbless squamates has an increased contact with the substrate compared with limbed counterparts. Comparatively, the contact with the substrate is intensified in fossorial species, where the whole circumference of the body interacts with the soil during underground locomotion. Although fossoriality in Squamata, specifically lizards and snakes, has been studied ecologically and morphologically (e.g., osteological changes), not enough detail is yet available regarding changes in organs critical for underground lifestyle such as the skin. Here we used histological and microscopical techniques (scanning electron microscopy and transmission electron microscopy) to uncover the structural detail of the epidermis and dermis in three limbless reptiles, the amphisbaenian Diplometopon zarudnyi, and two snakes, Indotyphlops braminus (Typhlopidae) and Cerastes cerastes (Viperidae). The skin of these taxa shows pronounced morphological diversity, which is likely associated to different environmental and functional demands upon these reptiles. Anat Rec, 299:979-989, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Adaptação Fisiológica , Meio Ambiente , Répteis/anatomia & histologia , Répteis/fisiologia , Pele/anatomia & histologia , Água/química , Animais , Clima Desértico , Técnicas Histológicas , Répteis/classificação
7.
Oxid Med Cell Longev ; 2016: 2646840, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26966507

RESUMO

Parsley was used as a probe of the current experiment to prevent the behavioral, morphological and biochemical changes in the newborn brain following the administration of cadmium (Cd) to the pregnant mice. The nonanesthetized pregnant mice were given daily parsley juice (Petroselinum crispum) at doses of 20 mg/kg and 10 mg/kg. Pregnant mothers were given Cd at a dose of 30 mg/kg divided into 3 equal times. The newborns have been divided into 6 groups: Group A, mothers did not take treatment; Groups B and C, mothers were treated with low and high dose of parsley, respectively; Group D, mothers were treated only with Cd (perinatal intoxication); Groups E and F, mothers were treated with Cd doses and protected by low and high doses of parsley, respectively. Light microscopy showed that Cd-induced neuronal degeneration by chromatolysis and pyknosis in the brain regions. The low dose of parsley 10 g/kg/day exhibited significant effects in neutralizing and reducing the deleterious changes due to Cd exposure during pregnancy on the behavioral activities, neurotransmitters, oxidative stress, and brain neurons morphology of the mice newborns.


Assuntos
Encéfalo/efeitos dos fármacos , Cádmio/toxicidade , Sucos de Frutas e Vegetais , Fármacos Neuroprotetores/farmacologia , Petroselinum , Extratos Vegetais/farmacologia , Animais , Animais Recém-Nascidos , Encéfalo/crescimento & desenvolvimento , Citoproteção/efeitos dos fármacos , Feminino , Masculino , Camundongos , Degeneração Neural/patologia , Degeneração Neural/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos , Petroselinum/química , Gravidez , Efeitos Tardios da Exposição Pré-Natal/patologia , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle
8.
Zoolog Sci ; 29(11): 770-5, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23106563

RESUMO

The morphology of many organisms seems to be related to the environments in which they live. Many snakes are so similar in their morphological patterns that it becomes quite difficult to distinguish any adaptive divergence that may have occurred. Many authors have suggested that the microstructure of the reptile's scales has important functional value. Herein, we investigate variations on the micromorphology of the external surface of dorsal scales on the head, the mid-body region (trunk), and the tail of Rhomphotyphlops braminus (Typhlopidae), Eryx jaculus (Boidae), Psammophis sibilans (Colubridae), Naja haje (Elapidae) and Echis carinatus (Viperidae). The specimens were metallized and analyzed by scanning electron microscopy. All species displayed unique dorsal scale surface microstructures of the investigated regions. The microstructural pattern of the scales of head, trunk, and tail differs in different species of these snakes. In conclusion, we detected ecomorphologic relationships between extant dorsal scale microstructures and snake microhabitat, enabling us to hypothesize that environmental pressures have significant influences not only on these animals' macrostructure, but also on its microstructure as well.


Assuntos
Tegumento Comum/anatomia & histologia , Serpentes/anatomia & histologia , Animais , Egito , Microscopia Acústica
9.
Int J Dev Neurosci ; 30(7): 545-53, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22926001

RESUMO

The present investigation aimed to show the differences in the development of sensorimotor reflexes and their relationship to the structural changes in spinal cord, cerebellum and cerebral cortex in three rodent species. The three species are albino rats (A-Rats), black-hooded rats (B-Rats) and albino mice. The development of selected reflexes was examined from day (D1) to D21. The structural changes were investigated at D7, D14, and D21. The following reflexes were analyzed: fore-limb/hind-limb grasp, surface body righting, fore-limb hopping, chin tactile placing, visual placing and body righting in the air. The developmental pattern of the reflexes was different in three rodent species. Although the black-hooded rats and albino rats belong to the same species, they are different in their appearance and developmental pattern. The development of external features and sensorimotor reflexes appeared earlier in mice than in A-Rats and B-Rats. At D7, differentiation of neurons was observed in the spinal cord while in cerebellum and cerebrum the neurons were found to be undifferentiated. At D14 and D21, the differentiated neurons were observed in spinal cord, cerebellum and cerebrum. Our data indicate that the developmental pattern of the reflexes in rodents may not be species specific but may be related to the animal strain.


Assuntos
Córtex Cerebelar/crescimento & desenvolvimento , Córtex Cerebelar/fisiologia , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/fisiologia , Reflexo/fisiologia , Medula Espinal/crescimento & desenvolvimento , Medula Espinal/fisiologia , Animais , Animais Recém-Nascidos , Peso Corporal/fisiologia , Cabelo/crescimento & desenvolvimento , Cabelo/fisiologia , Força da Mão/fisiologia , Locomoção/fisiologia , Camundongos , Atividade Motora , Equilíbrio Postural/fisiologia , Ratos , Especificidade da Espécie , Tato/fisiologia , Visão Ocular/fisiologia
10.
Zoolog Sci ; 28(10): 743-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21967222

RESUMO

We studied beneficial difference of the skin of two snakes. Two snakes were chosen from two different habitats and two families: Colubridae (Natrix tessellata) and Viperidae (Cerastes vipera). The investigations were performed by light and electron microscopy. Histologically, the skin of the studied species show pronounced modifications that correlated with functional demands. The scales in Natrix tessellata overlapped slightly, while in Cerastes vipera they were highly overlapped. SEM shows that scales of Natrix tessellata had bidentate tips while the scales of Cerastes vipera were keeled. Histochemically, in both studied species, melanocytes and collagenous fibres were distributed throughout the dermis. Polysaccharides were highly concentrated in the epidermis and dermis of both species while proteins were highly concentrated only in the epidermis. Transmission electron microscopy (TEM) showed that the skin of both snakes consisted of keratins located in the epidermis. Some lipids and mucus were incorporated into the outer scale surfaces such that lipids were part of the fully keratinised hard layer of the snakes' skins. Lipids are probably responsible for limiting water loss and ion movements across the skin. Melanosomes from epidermal melanocytes were present only in Cerastes vipera. In aggregate, these results indicate that snakeskin may provide an ecological indicator whereby epidermal and integumentary specializations may be ecologically correlated.


Assuntos
Colubridae/anatomia & histologia , Pele/anatomia & histologia , Viperidae/anatomia & histologia , Adaptação Fisiológica , Animais , Colubridae/fisiologia , Ecossistema , Especificidade da Espécie , Viperidae/fisiologia
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