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1.
Mol Biol Rep ; 50(12): 9887-9895, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37864661

RESUMO

BACKGROUND: Tramadol is one of the most commonly abused substances in the Middle East. Furthermore, smoking is extremely common among the population. METHODS: An experimental study was performed on Sprague-Dawley rats to explore the effects of both nicotine and tramadol on the liver and testes. The tramadol was administered at 10 and 20 mg/kg, respectively, while the nicotine was administered at 125 mg/kg. Histological examination and androgen receptor ELISA assay showed mild effects on the liver and proofed safety on the testis. Western blot analysis of BIP (immunoglobulin heavy-chain binding protein) and CHOP (CCAAT-enhancer-binding protein homologous protein) revealed that fewer problems were induced by adding nicotine to tramadol. Autophagy marker LCIII and apoptosis marker caspase-8 showed similar effects to CHOP and BIP on liver samples. The real-time PCR of BIP expression showed similar but not identical results. CONCLUSIONS: The results showed mild endoplasmic reticulum stress, autophagy, and apoptosis in the liver samples. Histological examination revealed stable spermatogenesis with average androgen receptor blood levels in the different groups.


Assuntos
Testículo , Tramadol , Ratos , Masculino , Animais , Nicotina/farmacologia , Tramadol/metabolismo , Tramadol/farmacologia , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Ratos Sprague-Dawley , Fígado/metabolismo , Apoptose , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático
2.
World J Clin Cases ; 11(20): 4843-4851, 2023 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-37583982

RESUMO

BACKGROUND: Sudden death is unanticipated, non-violent death taking place within the first 24 h after the onset of symptoms. It is a major public health problem worldwide. Moreover, the effects of living at moderate altitude on mortality are poorly understood. AIM: To retrospectively report the frequency and the main causes of sudden deaths in relation to total deaths at Asir Central Hospital, 2255 m above sea level, in the southern region of Saudi Arabia over a period of 4 years from 2013 to 2016. METHODS: The medical records of 1821 deaths were examined and showed 353 cases (19.4%) of sudden death. RESULTS: The highest incidence of sudden death was among the elderly (51%), whereas, the lowest was among children and adolescents (6.5%). With regard to gender, the incidence of sudden death was higher in males (54.4%) compared to 45.6% in females. In this study, we found that the most common direct causes of sudden death were cardiovascular diseases (29.2%), respiratory disease (22.7%), infectious disease (12.2%), cancer (9.4%) and hematological diseases (6.2%). With respect to seasonal variation, the highest incidence was during winter (31.32%) followed by summer (25.8%). CONCLUSION: The results of this study will help emergency physicians and health care providers to exercise due care to reduce the incidence of sudden death and raise public awareness about the impact of sudden death.

3.
Viruses ; 14(12)2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36560787

RESUMO

A new Coronaviridae strain, Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), emerged from Wuhan city of China and caused one of the substantial global health calamities in December 2019. Even though several vaccines and drugs have been developed worldwide since COVID-19, a cost-effective drug with the least side effects is still unavailable. Currently, plant-derived compounds are mostly preferred to develop antiviral therapeutics due to its less toxicity, easy access, and cost-effective characteristics. Therefore, in this study, 124 phytochemical compounds from plants of Lauraceae family with medicinal properties were virtually screened against SARS-CoV-2 Mpro. Identification of four phytomolecules, i.e., cassameridine, laetanine, litseferine and cassythicine, with docking scores -9.3, -8.8, -8.6, and -8.6 kcal/mol, respectively, were undertaken by virtual screening, and molecular docking. Furthermore, the molecular dynamic simulation and essential dynamics analysis have contributed in understanding the stability and inhibitory effect of these selected compounds. These phytomolecules can be considered for further in vitro and in vivo experimental study to develop anti-SARS-CoV-2 therapeutics targeting the main protease (Mpro).


Assuntos
Antivirais , COVID-19 , Humanos , Antivirais/farmacologia , Antivirais/química , SARS-CoV-2 , Simulação de Acoplamento Molecular , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Simulação de Dinâmica Molecular
4.
Mediators Inflamm ; 2022: 3300903, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248189

RESUMO

Neurodegenerative disorders are marked by neuronal death over time, causing a variety of cognitive and motor dysfunctions. Protein misfolding, neuroinflammation, and mitochondrial and protein clearance system dysfunction have all been identified as common pathways leading to neurodegeneration in recent decades. An altered microbiome of the gut, which is considered to play a central role in diseases as well as health, has recently been identified as another potential feature seen in neurodegenerative disorders. An array of microbial molecules that are released in the digestive tract may mediate gut-brain connections and permeate many organ systems, including the nervous system. Furthermore, recent findings from clinical as well as preclinical trials suggest that the microbiota of the gut plays a critical part in gut-brain interplay and that a misbalance in the composition of the gut microbiome may be linked to the etiology of neurological disorders (majorly neurodegenerative health problems); the underlying mechanism of which is still unknown. The review aims to consider the association between the microbiota of the gut and neurodegenerative disorders, as well as to add to our understanding of the significance of the gut microbiome in neurodegeneration and the mechanisms that underlie it. Knowing the mechanisms behind the gut microbiome's role and abundance will provide us with new insights that could lead to novel therapeutic strategies.


Assuntos
Microbioma Gastrointestinal , Microbiota , Doenças Neurodegenerativas , Encéfalo , Microbioma Gastrointestinal/fisiologia , Humanos
5.
Oxid Med Cell Longev ; 2022: 6038996, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36071869

RESUMO

Alzheimer's disease (AD) is one of the serious and progressive neurodegenerative disorders in the elderly worldwide. Various genetic, environmental, and lifestyle factors are associated with its pathogenesis that affect neuronal cells to degenerate over the period of time. AD is characterized by cognitive dysfunctions, behavioural disability, and psychological impairments due to the accumulation of amyloid beta (Aß) peptides and neurofibrillary tangles (NFT). Several research reports have shown that flavonoids are the polyphenolic compounds that significantly improve cognitive functions and inhibit or delay the amyloid beta aggregation or NFT formation in AD. Current research has uncovered that dietary use of flavonoid-rich food sources essentially increases intellectual abilities and postpones or hinders the senescence cycle and related neurodegenerative problems including AD. During AD pathogenesis, multiple signalling pathways are involved and to target a single pathway may relieve the symptoms but not provides the permanent cure. Flavonoids communicate with different signalling pathways and adjust their activities, accordingly prompting valuable neuroprotective impacts. Flavonoids likewise hamper the movement of obsessive indications of neurodegenerative disorders by hindering neuronal apoptosis incited by neurotoxic substances. In this short review, we briefly discussed about the classification of flavonoids and their neuroprotective properties that could be used as a potential source for the treatment of AD. In this review, we also highlight the structural features of flavonoids, their beneficial roles in human health, and significance in plants as well as their microbial production.


Assuntos
Doença de Alzheimer , Fármacos Neuroprotetores , Idoso , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Flavonoides/metabolismo , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Humanos , Emaranhados Neurofibrilares/metabolismo , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico
6.
Parasitol Res ; 121(1): 35-48, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34842987

RESUMO

New antiparasitic drugs are urgently required for treating parasitic infections. The marine environment has proven to be a valuable source of compounds with therapeutic properties against many diseases, including parasitic diseases. Cnidarian venoms are known for their toxicological properties and are candidates for developing medications. In this review, the antiparasitic properties of cnidarian toxins, discovered over the last two decades, were examined. A total of 61 cnidarian compounds from 18 different genera of cnidaria were studied for their antiparasitic activities. The assessed genera belonged mainly to three geographical areas: South America, North America, and Southeast Asia. The in vitro activities of crude extracts and compounds against a range of parasites including Plasmodium falciparum, Trypanosoma brucei gambiense, T. cruzi, T. congolense, Leishmania donovani, L. chagasi, L. braziliensis, and Giardia duodenalis are reviewed. The challenges involved in developing these compounds into effective drugs are discussed.


Assuntos
Cnidários , Leishmania donovani , Animais , Antiparasitários , Testes de Sensibilidade Parasitária , Plasmodium falciparum
7.
Polymers (Basel) ; 13(24)2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34960859

RESUMO

κ-carrageenan is useful for its superior gelling, hydrogel, and thickening properties. The purpose of the study was to maximize the hydrogel properties and water-absorbing capacity of κ-carrageenan by blending it with starch from potato peels to be used as safe and biodegradable water-absorbent children's toys. The prepared materials were analyzed using FTIR and Raman spectroscopy to analyze the functional groups. Results showed that there was a shift in the characteristic peaks of starch and κ-carrageenan, which indicated their proper reaction during blend formation. In addition, samples show a peak at 1220 cm-1 corresponding to the ester sulfate groups, and at 1670 cm-1 due to the carbonyl group contained in D-galactose. SEM micrographs showed the presence of rough surface topology after blending the two polymers, with the appearance of small pores. In addition, the presence of surface cracks indicates the biodegradability of the prepared membranes that would result after enzymatic treatment. These results are supported by surface roughness results that show the surface of the κ-carrageenan/starch membranes became rougher after enzymatic treatment. The hydrophilicity of the prepared membranes was evaluated from contact angle (CA) measurements and the swelling ratio. The swelling ratio of the prepared membranes increased gradually as the starch ratio increased, reaching 150%, while the water-uptake capacity increased from 48 ± 4% for plain κ-carrageenan to 150 ± 5% for 1:2 κ-carrageenan/starch blends. The amylase enzyme showed an effective ability to degrade both the plain κ-carrageenan and κ-carrageenan/starch membranes, and release glucose units for up to 236 and 563, respectively. According to these results, these blends could be effectively used in making safe and biodegradable molded toys with superior water-absorbing capabilities.

8.
Antibiotics (Basel) ; 10(11)2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34827266

RESUMO

Staphylococcus species cause diseases in animals and humans. The prevalence and antimicrobial profiles of Staphylococcus spp. in animals and human samples in the Minya Governorate, Egypt, were determined, and resistance- and virulence-associated genes were observed in multidrug-resistant (MDR) isolates. Moreover, the antibacterial effect of carvacrol essential oil (EO) on the MDR isolates was studied. A total of 216 samples were aseptically collected from subclinically mastitic cow's milk (n = 100), sheep abscesses (n = 25) and humans (n = 91). Out of 216 samples, a total of 154 single Staphylococcus species (71.3%) were isolated. The most frequent bacterial isolates were S. aureus (43%), followed by S. schleiferi (25%), S. intermedius (12%), S. xylosus (12%), S. haemolyticus (4.5%), S. epidermidis (2%) and S. aurecularis (1%). Haemolytic activity and biofilm production were detected in 77 and 47% of isolates, respectively. Antimicrobial susceptibility testing showed a high degree of resistance to the most commonly used antimicrobials in human and veterinary practices. The mecA, vanA, vanC1 and ermC resistance genes were detected in 93, 42, 83 and 13% of isolates, respectively. Moreover, hla, icaA and icaD virulence genes were detected in 50, 75 and 78% of isolates, respectively. Carvacrol effectively inhibited the growth of all tested isolates at concentrations of 0.1, 0.05 and 0.04% while a concentration of 0.03% inhibited 75% of isolates. Interestingly, some phenotypic changes were observed upon treatment with a carvacrol oil concentration of 0.03%. All the treated MDR Staphylococcus isolates changed from multidrug resistant to either susceptible or intermediately susceptible to 2-3 antimicrobials more than parental bacterial isolates. Real-time PCR was applied for the detection of the differential expression of mecA and vanC1 genes before and after treatment with carvacrol which revealed a mild reduction in both genes' expression after treatment. Staphylococcus spp. Containing MDR genes are more likely to spread between humans and animals. From these results, carvacrol EO is a promising natural alternative to conventional antimicrobials for pathogens impacting human health and agriculture due to its potential antimicrobial effect on MDR pathogens; even in sub-lethal doses, carvacrol EO can affect their phenotypic properties and genes' expression.

9.
Toxicol Rep ; 8: 1226-1228, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34195013

RESUMO

BACKGROUND: Apnoea and prolonged paralysis after succinylcholine administration is not uncommon occurrence in anaesthetic practice. It occurs due to inherited or acquired deficiency of butyrylcholinesterase. CASE REPORT: Here we report a case of succinylcholine apnoea for 2 h in a 5 years old girl who was anaesthetized for bronchoscopic extraction of a foreign body. She was subsequently kept on assisted ventilation. She recovered few minutes after I.V. atropine and naloxone. Laboratory investigation revealed low cholinesterase activity. Thus the girl was given 150 mL fresh frozen plasma. She has been discharged the next day after complete recovery. CONCLUSION: As the genetic analysis was not available to confirm the diagnosis of atypical variant of cholinesterase. The family was advised to submit serum samples for assessment of cholinesterase activity and avoid exposure to cholinesterase inhibitors. Moreover, clear instructions were given to the family so they can warn the anaesthetists in case any family member undergoes general anesthesia for any reason in the future. Furthermore, they must be strongly advised to avoid exposure to anticholinesterases as they might have heightened sensitivity to these agents. It should be emphasized that Naloxone and atropine could help speed up recovery in such cases.

10.
Int. j. morphol ; 38(3): 530-535, June 2020. graf
Artigo em Inglês | LILACS | ID: biblio-1098283

RESUMO

Dysregulated autophagy, whether excessive or downregulated, has been thought to be associated with neurodegenerative disorders including Parkinson's disease. Accordingly, the present study was carried out to investigate whether 3-methyladenine, an autophagy inhibitor, can modulate the effects of rotenone on dopaminergic neurons in primary mesencephalic cell culture. Cultures were prepared from embryonic mouse mesencephala at gestation day 14. Four groups of cultures were treated on the 10th DIV for 48 h as follows: the first was kept as an untreated control, the second was treated with 3-methyladenine alone (1, 10, 100, 200 mM), the third was treated with 20 nM rotenone and the fourth was co-treated with 20 nM rotenone and 3-methyladenine (1, 10, 100, 200 mM). On the 12th DIV, cultured cells were stained immunohistochemically against tyrosine hydroxylase and culture media were used to measure the levels of lactate dehydrogenase. 3methyladenine had no effects on both the survival of dopaminergic neurons and the release of lactate dehydrogenase. Rotenone significantly decreased the number of dopaminergic neurons and increased the levels of lactate dehydrogenase in the culture media. When cultures concomitantly treated with 3-methyladenine and rotenone, 3-methyladenine had no effect against rotenone-induced dopaminergic cell damage and lactate dehydrogenase release into the culture medium. In conclusion, the autophagy inhibitor 3-methyladenine could not modulate rotenone-induced dopaminergic cell damage in primary mesencephalic cell culture.


Se estima que la autofagia desregulada, ya sea excesiva o con baja regulación, está asociada con trastornos neurodegenerativos, incluyendo la enfermedad de Parkinson. En consecuencia, el se realizó este estudio para investigar si la 3metiladenina, un inhibidor de la autofagia,puede modular los efectos de la rotenona en las neuronas dopaminérgicas en el cultivo primario de células mesencefálicas. Los cultivos se prepararon a partir de mesencéfalo de ratón embrionario el día 14 de gestación. Cuatro grupos de cultivos se trataron en el 10º DIV durante 48 h de la siguiente manera: el primer grupo se mantuvo como un control no tratado, el segundo se trató con 3-metiladenina sola (1, 10, 100, 200 mM), el tercer grupo se trató con rotenona 20 nM y el cuarto se trató conjuntamente con rotenona 20 nM y 3-metiladenina (1, 10, 100, 200 mM). En el 12º DIV; las células cultivadas fueron tratadas mediante tinción inmunohistoquímica en tirosina hidroxilasa y se usaron medios de cultivo para medir los niveles de lactato deshidrogenasa. La 3-metiladenina no tuvo efectos tanto en la supervivencia de las neuronas dopaminérgicas como en la liberación de lactato deshidrogenasa. La rotenona disminuyó significativamente el número de neuronas dopaminérgicas y se observó un aumento de los niveles de lactato deshidrogenasa en los medios de cultivo. Cuando los cultivos tratados concomitantemente con 3-metiladenina y rotenona, la 3metiladenina no tuvo efecto contra el daño celular dopaminérgico inducido por la rotenona y la liberación de lactato deshidrogenasa en el medio de cultivo. En conclusión, el inhibidor de la autofagia 3-metiladenina no moduló el daño celular dopaminérgico inducido por la rotenona en el cultivo celular mesencefálico primario.


Assuntos
Animais , Camundongos , Doença de Parkinson , Rotenona/toxicidade , Adenina/análogos & derivados , Autofagia , Mesencéfalo , Adenina/farmacologia , Células Cultivadas , Morte Celular/efeitos dos fármacos , Neurônios Dopaminérgicos/efeitos dos fármacos , L-Lactato Desidrogenase/análise
11.
J Toxicol Pathol ; 33(2): 87-95, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32425341

RESUMO

This study investigated the protective effects of minocycline against acrylamide (ACR)-induced neurotoxicity and testicular damage in Sprague-Dawley rats. Forty rats were divided into five groups (eight rats each). Group I received saline (0.5 mL/rat) daily for 10 days and served as the untreated control group. Group II received ACR (30 mg/kg body weight (b.w.)) daily for 10 days. Group III received ACR (30 mg/kg b.w.) daily for 10 days and subsequently minocycline (60 mg/kg b.w.) for five days. Group IV received ACR (30 mg/kg b.w.) daily for 10 days followed by saline for five days and served as the control group for the ACR-minocycline-treated group. Group V received minocycline (60 mg/kg b.w.) for five days. All treatments were administered orally. Rats in group I and V showed normal locomotor behavior and normal histology of the brain and testes. Administration of ACR (Group II and IV) resulted in weight loss and gait abnormalities. Furthermore, neuronal degeneration in the hippocampus and cerebellum and degeneration of the seminiferous tubular epithelium with formation of spermatid giant cells were observed. Ultrastructurally, ACR specifically damaged spermatogonia and spermatocytes. Acrylamide was also seen to cause a significant increase of malondialdehyde levels in the brain and testes. Treatment of ACR-administered rats with minocycline (Group III) significantly alleviated the loss of body weight and improved locomotor function. Minocycline also ameliorated neuronal degeneration and seminiferous tubular damage and decreased malondialdehyde concentrations. In conclusion, minocycline protects against neurotoxic effects of acrylamide and seminiferous tubular damage. Decreasing lipid peroxidation by minocycline might play a role in such protection.

12.
Folia Neuropathol ; 57(2): 196-204, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31556578

RESUMO

INTRODUCTION: Exposure to acrylamide is increasing worldwide as a result of its heavy use in industry and formation in carbohydrate-rich food cooked at high temperature. Despite its neurotoxicity, no studies have shown its toxic effects on dopaminergic neurons yet. Therefore, the current study was carried out to show whether acrylamide adversely affects primary cultured dopaminergic neurons. MATERIAL AND METHODS: Acrylamide (0.001, 0.01, 0.1, 1, 2 mM) was added to two different groups of primary mesencephalic cell cultures on the 9th day in vitro for 24 and 48 h, respectively. Moreover, a group of cultures was treated with lower concentrations of acrylamide (0.01, 0.05, 0.1, 0.5 mM) on the 6th day in vitro for 5 consecutive days to investigate its long-term effects on dopaminergic neurons. Following each treatment, culture media were obtained for measuring lactate dehydrogenase, and cultured cells were stained immunocytochemically against tyrosine hydroxylase and neuronal nuclear antigens. RESULTS: Treatment of cultures with acrylamide for 48 h significantly reduced the number of dopaminergic neurons, adversely altered the morphology of the surviving neurons and increased levels of lactate dehydrogenase in the culture media. Similar treatment of cultures with acrylamide also resulted in lower numbers of total neuronal cells as shown by a reduced expression of the neuronal nuclear antigen. Prolonged treatment of cultures with lower concentrations of acrylamide slightly reduced the survival of dopaminergic neurons but increased the release of lactate dehydrogenase into the culture media as well. CONCLUSIONS: The current study shows, for the first time, neurotoxicity of acrylamide on dopaminergic neurons in the primary mesencephalic cell culture.


Assuntos
Acrilamida/toxicidade , Morte Celular/efeitos dos fármacos , Neurônios Dopaminérgicos/efeitos dos fármacos , Mesencéfalo/efeitos dos fármacos , Animais , Células Cultivadas , Neurônios Dopaminérgicos/citologia , L-Lactato Desidrogenase/análise , Mesencéfalo/citologia , Camundongos
13.
Folia Neuropathol ; 57(4): 317-326, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32337944

RESUMO

Rotenone ([2R-(2α,6aα,12aα)]-1,2,12,12a-tetrahydro-8,9-dimethoxy-2-(1-methylethenyl)-[1]benzopyran[3,4-b]furo [2,3-h][1]benzopyran-6(6aH)-one) is a naturally occurring compound derived from the roots and stems of Derris, Tephrosia, Lonchocarpus and Mundulea plant species. Since its discovery at the end of the 19th century, rotenone has been widely used as a pesticide for controlling insects, ticks and lice, and as a piscicide for management of nuisance fish in lakes and reservoirs. In 2000, Betarbet et al. reproduced most of the behavioural, biochemical and pathological features of Parkinson's disease (PD) in rotenone-treated rats. Since that time, rotenone has received much attention as it would be one of the environmental neurotoxins implicated in etiopathogenesis of PD. Moreover, it represents a common experimental model to investigate the underlying mechanisms leading to PD and evaluate the new potential therapies for the disease. In the current general review, we aimed to address recent advances in the hazards of the environmental applications of rotenone and discuss the updates on the rotenone model of PD and whether it is implicated in the etiopathogenesis of the disease.


Assuntos
Inflamação/tratamento farmacológico , Doença de Parkinson/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Rotenona/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Modelos Animais de Doenças , Humanos
14.
Toxicol In Vitro ; 52: 279-285, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30017864

RESUMO

Domoic acid, an excitatory neurotoxin produced by certain algae, reaches the food chain through accumulation in some sea organisms. To investigate its long-term neurotoxicity on dopaminergic neurons, prepared primary mesencephalic cell cultures were exposed to different concentrations of domoic acid (0.1, 1, 10, 100 µM) on the 8th day in vitro (DIV) for 4 days. On the 12th DIV, culture media were collected for measurement of lactate dehydrogenase and cultured cells were subjected to immunohistochemistry against tyrosine hydroxylase, neuronal nuclear antigen and glial fibrillary acidic protein, and fluorescence staining using H2DCFDA, JC-1 and Hoechst 33342 dyes. Moreover, roles of AMPA/KA and NMDA receptors in domoic acid neurotoxicity were also investigated. Domoic acid significantly decreased the number of dopaminergic neurons and adversely affected their morphology, and slightly reduced the expression of neuronal nuclear antigen and glial fibrillary acidic protein. Co-treatment of cultures with domoic acid and the AMPA/KA or NMDA receptor antagonists NBQX and MK-801 rescued significant number of dopaminergic neurons. Domoic acid significantly decreased red:green fluorescence ratio of JC-1 and did not affect production of reactive oxygen species and apoptotic cell death. In conclusions, the present study reveals that long-term treatment of primary mesencephalic cell culture with domoic acid significantly destroyed dopaminergic neurons. This effect appears to be attributed to activation of AMPA/KA and NMDA receptors and mitochondrial damage.


Assuntos
Neurônios Dopaminérgicos/efeitos dos fármacos , Ácido Caínico/análogos & derivados , Fármacos Neuromusculares Despolarizantes/toxicidade , Neurotoxinas/toxicidade , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Maleato de Dizocilpina/farmacologia , Neurônios Dopaminérgicos/fisiologia , Ácido Caínico/toxicidade , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mesencéfalo/citologia , Camundongos , Quinoxalinas/farmacologia , Receptores de AMPA/antagonistas & inibidores , Receptores de AMPA/fisiologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/fisiologia
15.
Ultrastruct Pathol ; 42(4): 358-364, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29952682

RESUMO

Injury to lacrimal glands represents a major health problem after radiation therapy of the head and neck malignancies. Accordingly, this study aimed to investigate significant ultrastructural changes of lacrimal glands and some of their underlying mechanisms following the exposure to different fractionated doses of irradiation. In this study, 28 Sprague Dawley (SD) rats were assigned to four groups (seven rats each): Group I acted as control and received no irradiation. Groups II-IV received fractionated irradiation of 5 Gy (100 cGy/fraction daily for 5 days), 9 Gy (300 cGy/fraction daily for 3 days), and 20 Gy (one fraction), respectively. One month after the experiment, examination of lacrimal glands with transmission electron microscopy (TEM) demonstrated dose-dependent ultrastructural changes in the lacrimal acinar and intralobular ductal epithelial cells. In the acinar cells, there were swollen rough endoplasmic reticulum, irregularly shaped nuclei with chromatin condensation, mitochondrial damage, and retention of secretory granules. Intaralobular ductal epithelial cells showed loss of surface microvilli and damage to mitochondria. In addition to the potential direct effects of irradiation on lacrimal acinar and intralobular ductal epithelial cells, damage to blood vessels and nerve endings seemed to mediate some of the underlying mechanisms of these irradiation-induced ultrastructural changes. In conclusion, using TEM reveals that lacrimal gland is highly sensitive to even small doses of irradiation therapy; in addition, swelling of rough endoplasmic reticulum and aberrant nuclei are the most encountered structural changes. Damage to blood vessels and nerve endings might mediate some of the underlying mechanisms of irradiation-induced secondary injury in lacrimal glands.


Assuntos
Retículo Endoplasmático Rugoso/ultraestrutura , Aparelho Lacrimal/efeitos da radiação , Aparelho Lacrimal/ultraestrutura , Mitocôndrias/ultraestrutura , Lesões por Radiação , Animais , Núcleo Celular/ultraestrutura , Microscopia Eletrônica de Transmissão , Ratos Sprague-Dawley
16.
Folia Neuropathol ; 56(1): 39-48, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29663739

RESUMO

INTRODUCTION: Domoic acid is a potent marine neurotoxin produced by certain species of the diatom genus Pseudonitzschia. To our knowledge, there are no studies that have investigated neurotoxic effects of domoic acid on dopaminergic neurons. Accordingly, the present study was carried out to investigate the potential neurotoxic effects of domoic acid on dopaminergic neurons in primary mesencephalic cell culture. MATERIAL AND METHODS: Cultures prepared from embryonic mouse mesencephala (total of 250 embryos) were treated with different concentrations of domoic acid (0.1, 1, 10, 100 µM) on the 10th DIV for 48 h. On the 12th DIV, culture media were used for measurement of lactate dehydrogenase and cultured cells were subjected to immunostaining for tyrosine hydroxylase, neuronal nuclear antigen and glial fibrillary acidic protein, and fluorescence staining using H2DCFDA, JC-1 and DAPI stains. Moreover, roles of AMPA/KA and NMDA receptors in domoic acid neurotoxicity were also investigated. RESULTS: Domoic acid significantly decreased the number of dopaminergic neurons, decreased the expression of neuronal nuclear antigen and slightly affected astrocyte populations, and increased the release of lactate dehydrogenase into the culture media. AMPA/KA receptor antagonist NBQX but not NMDA receptor antagonist MK-801 significantly inhibited the neurotoxic effect of domoic acid on dopaminergic neurons. H2DCFDA, JC-1 and DAPI fluorescence staining, respectively, revealed that DomA slightly raised ROS production, and significantly decreased mitochondrial membrane potential and increased apoptotic cell death of cultured cells. CONCLUSION: The current study presents for the first time the neurotoxic effects of domoic acid on dopaminergic neurons and this effect appears to be attributed to activation of AMPA/KA receptors on dopaminergic neurons.


Assuntos
Neurônios Dopaminérgicos/efeitos dos fármacos , Ácido Caínico/análogos & derivados , Fármacos Neuromusculares Despolarizantes/toxicidade , Animais , Células Cultivadas , Ácido Caínico/toxicidade , Doença de Parkinson
17.
Ultrastruct Pathol ; 42(3): 255-261, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29565703

RESUMO

Medicinal plants have recently gained increasing scientific interest as an important source of molecules with different therapeutic potentials. Accordingly, the present study was carried out to investigate ultrastructural changes induced by the aqueous extract of Solanum incanum (SI) fruit on human colorectal carcinoma cell line (HCT 116 cells). Examination of SI-treated HCT 116 cells with transmission electron microscopy (TEM) demonstrated numerous ultrastructural changes in the form of loss of the surface microvilli, mitochondrial damage and dilatation of cristae, and formation of autophagic vacuoles and increasing numbers of lipid droplets. Also, majority of the treated cells showed nuclear shrinkage with chromatin condensation and nucleolar changes. Moreover, some cells showed focal areas of cytoplasmic degeneration associating with formation of myelin figures and fatty globules. In conclusion, TEM was able to verify cytotoxicity of SI aqueous extract against HCT 116 colon cancer cells.


Assuntos
Antineoplásicos/farmacologia , Neoplasias do Colo/ultraestrutura , Extratos Vegetais/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Frutas , Células HCT116 , Humanos , Microscopia Eletrônica de Transmissão , Solanum
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