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1.
Nat Neurosci ; 27(6): 1125-1136, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38710875

RESUMO

Cortical malformations such as focal cortical dysplasia type II (FCDII) are associated with pediatric drug-resistant epilepsy that necessitates neurosurgery. FCDII results from somatic mosaicism due to post-zygotic mutations in genes of the PI3K-AKT-mTOR pathway, which produce a subset of dysmorphic cells clustered within healthy brain tissue. Here we show a correlation between epileptiform activity in acute cortical slices obtained from human surgical FCDII brain tissues and the density of dysmorphic neurons. We uncovered multiple signatures of cellular senescence in these pathological cells, including p53/p16 expression, SASP expression and senescence-associated ß-galactosidase activity. We also show that administration of senolytic drugs (dasatinib/quercetin) decreases the load of senescent cells and reduces seizure frequency in an MtorS2215F FCDII preclinical mouse model, providing proof of concept that senotherapy may be a useful approach to control seizures. These findings pave the way for therapeutic strategies selectively targeting mutated senescent cells in FCDII brain tissue.


Assuntos
Convulsões , Serina-Treonina Quinases TOR , Animais , Serina-Treonina Quinases TOR/metabolismo , Camundongos , Humanos , Convulsões/tratamento farmacológico , Senoterapia/farmacologia , Senescência Celular/efeitos dos fármacos , Dasatinibe/farmacologia , Epilepsia/tratamento farmacológico , Masculino , Malformações do Desenvolvimento Cortical/tratamento farmacológico , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Feminino
2.
Ultrasound Med Biol ; 49(5): 1327-1336, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36878831

RESUMO

OBJECTIVE: It is unknown whether ultrasound-induced blood-brain barrier (BBB) disruption can promote epileptogenesis and how BBB integrity changes over time after sonication. METHODS: To gain more insight into the safety profile of ultrasound (US)-induced BBB opening, we determined BBB permeability as well as histological modifications in C57BL/6 adult control mice and in the kainate (KA) model for mesial temporal lobe epilepsy in mice after sonication with low-intensity pulsed ultrasound (LIPU). Microglial and astroglial changes in ipsilateral hippocampus were examined at different time points following BBB disruption by respectively analyzing Iba1 and glial fibrillary acidic protein immunoreactivity. Using intracerebral EEG recordings, we further studied the possible electrophysiological repercussions of a repeated disrupted BBB for seizure generation in nine non-epileptic mice. RESULTS: LIPU-induced BBB opening led to transient albumin extravasation and reversible mild astrogliosis, but not to microglial activation in the hippocampus of non-epileptic mice. In KA mice, the transient albumin extravasation into the hippocampus mediated by LIPU-induced BBB opening did not aggravate inflammatory processes and histologic changes that characterize the hippocampal sclerosis. Three LIPU-induced BBB opening did not induce epileptogenicity in non-epileptic mice implanted with depth EEG electrodes. CONCLUSION: Our experiments in mice provide persuasive evidence of the safety of LIPU-induced BBB opening as a therapeutic modality for neurological diseases.


Assuntos
Barreira Hematoencefálica , Epilepsia do Lobo Temporal , Camundongos , Animais , Barreira Hematoencefálica/metabolismo , Epilepsia do Lobo Temporal/terapia , Epilepsia do Lobo Temporal/induzido quimicamente , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Albuminas , Hipocampo
3.
eNeuro ; 10(3)2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36849262

RESUMO

Autoimmune encephalitis (AIE) associated with antibodies directed against the leucine-rich glioma inactivated 1 (LGI1) protein is the second most common AIE and is responsible for deleterious neocortical and limbic epileptic seizures. Previous studies demonstrated a pathogenic role of anti-LGI1 antibodies via alterations in the expression and function of Kv1 channels and AMPA receptors. However, the causal link between antibodies and epileptic seizures has never been demonstrated. Here, we attempted to determine the role of human anti-LGI1 autoantibodies in the genesis of seizures by analyzing the impact of their intracerebral injection in rodents. Acute and chronic injections were performed in rats and mice in the hippocampus and primary motor cortex, the two main brain regions affected by the disease. Acute infusion of CSF or serum IgG of anti-LGI1 AIE patients did not lead to the emergence of epileptic activities, as assessed by multisite electrophysiological recordings over a 10 h period after injection. A chronic 14 d injection, coupled with continuous video-EEG monitoring, was not more effective. Overall, these results demonstrate that acute and chronic injections of CSF or purified IgG from LGI1 patients are not able to generate epileptic activity by themselves in the different animal models tested.


Assuntos
Epilepsia , Peptídeos e Proteínas de Sinalização Intracelular , Humanos , Ratos , Camundongos , Animais , Leucina , Roedores , Convulsões/induzido quimicamente , Epilepsia/induzido quimicamente , Hipocampo , Imunoglobulina G
4.
Med Sci (Basel) ; 10(3)2022 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-36135835

RESUMO

Capsaicin acts on sensory nerves via vanilloid receptors. TRPV1 has been extensively studied with respect to functional lower urinary tract (LUT) conditions in rodents and humans. We aimed to (1) provide background information on capsaicin and TRPV1 and its mechanisms of action and basis for clinical use, (2) review the use of acute intravesical capsaicin instillation (AICI) in rodents to mimic various LUT disorders in which capsaicin sensitive C-fibers are involved and (3) discuss future innovative treatments. A comprehensive search of the major literature databases until June 2022 was conducted. Both capsaicin-sensitive and resistant unmyelinated bladder afferent C-fibers are involved in non-neurogenic overactive bladder/detrusor overactivity (OAB/DO). AICI is a suitable model to study afferent hyperactivity mimicking human OAB. Capsaicin-sensitive C-fibers are also involved in neurogenic DO (NDO) and potential targets for NDO treatment. AICI has been successfully tested for NDO treatment in humans. Capsaicin-sensitive bladder afferents are targets for NDO treatment. TRPV1-immunoreactive nerve fibers are involved in the pathogenesis of interstitial cystitis/painful bladder syndrome (IC/PBS). The AICI experimental model appears relevant for the preclinical study of treatments targeting bladder afferents for refractory IC/BPS. The activity of capsaicin-sensitive bladder afferents is increased in experimental bladder outlet obstruction (BOO). The AICI model may also be relevant for bladder disorders resulting from C-fiber hyperexcitabilities related to BOO. In conclusion, there is a rationale for the selective blockade of TRPV1 channels for various bladder disorders. The AICI model is clinically relevant for the investigation of pathophysiological conditions in which bladder C-fiber afferents are overexcited and for assessing innovative treatments for bladder disorders based on their pathophysiology.


Assuntos
Cistite Intersticial , Bexiga Urinária , Capsaicina/uso terapêutico , Cistite Intersticial/tratamento farmacológico , Cistite Intersticial/patologia , Humanos , Fibras Nervosas Amielínicas , Canais de Cátion TRPV , Bexiga Urinária/inervação , Bexiga Urinária/patologia
5.
Prog Neurobiol ; 213: 102262, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35283238

RESUMO

Autoimmune encephalitis associated with antibodies directed against the leucine-rich glioma inactivated 1 (LGI1) protein is responsible for specific tonic-dystonic motor seizures. Although dysfunctions in neuronal excitability have been associated with anti-LGI1 autoantibodies, their relation to seizures remain inconclusive. We developed a new in vivo experimental rat model to determine whether inhibition of Kv1.1 channels by dentrotoxin-K (DTX) in the primary motor cortex (M1) could recapitulate the human seizures and to elucidate their subtending cortical mechanisms. Comparing electro-clinical features of DTX-induced seizures in rats with those recorded from a cohort of anti-LGI1 encephalitis patients revealed striking similarities in their electroencephalographic (EEG) signature, frequency of recurrence and semiology. By combining multi-site extracellular and intracellular recordings of M1 pyramidal neurons in DTX rats, we demonstrated that the blockade of Kv1.1 channels induced a sequence of changes in neuronal excitability and synaptic activity, leading to massive suprathreshold membrane depolarizations underlying the paroxysmal EEG activity. Our results suggest the central role of Kv1.1 channels disruption in the emergence of anti-LGI1-associated seizures and suggest that this new rodent model could serve future investigations on ictogenesis in autoimmune encephalitis.


Assuntos
Encefalite , Glioma , Córtex Motor , Animais , Doença de Hashimoto , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Leucina , Ratos , Convulsões/induzido quimicamente
6.
Ann Neurol ; 91(1): 101-116, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34693554

RESUMO

OBJECTIVE: Germline loss-of-function mutations in DEPDC5, and in its binding partners (NPRL2/3) of the mammalian target of rapamycin (mTOR) repressor GATOR1 complex, cause focal epilepsies and increase the risk of sudden unexpected death in epilepsy (SUDEP). Here, we asked whether DEPDC5 haploinsufficiency predisposes to primary cardiac defects that could contribute to SUDEP and therefore impact the clinical management of patients at high risk of SUDEP. METHODS: Clinical cardiac investigations were performed in 16 patients with pathogenic variants in DEPDC5, NPRL2, or NPRL3. Two novel Depdc5 mouse strains, a human HA-tagged Depdc5 strain and a Depdc5 heterozygous knockout with a neuron-specific deletion of the second allele (Depdc5c/- ), were generated to investigate the role of Depdc5 in SUDEP and cardiac activity during seizures. RESULTS: Holter, echocardiographic, and electrocardiographic (ECG) examinations provided no evidence for altered clinical cardiac function in the patient cohort, of whom 3 DEPDC5 patients succumbed to SUDEP and 6 had a family history of SUDEP. There was no cardiac injury at autopsy in a postmortem DEPDC5 SUDEP case. The HA-tagged Depdc5 mouse revealed expression of Depdc5 in the brain, heart, and lungs. Simultaneous electroencephalographic-ECG records on Depdc5c/- mice showed that spontaneous epileptic seizures resulting in a SUDEP-like event are not preceded by cardiac arrhythmia. INTERPRETATION: Mouse and human data show neither structural nor functional cardiac damage that might underlie a primary contribution to SUDEP in the spectrum of DEPDC5-related epilepsies. ANN NEUROL 2022;91:101-116.


Assuntos
Epilepsias Parciais/complicações , Proteínas Ativadoras de GTPase/genética , Coração , Morte Súbita Inesperada na Epilepsia/etiologia , Adolescente , Adulto , Animais , Eletrocardiografia , Eletroencefalografia , Epilepsias Parciais/genética , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Mutação , Proteínas Supressoras de Tumor/genética , Adulto Jovem
7.
BMC Urol ; 20(1): 132, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32854676

RESUMO

BACKGROUND: The main purpose of this study is to investigate the effect of silodosin on the urodynamic consequences in a previously established model of lower urinary tract symptoms associated with benign prostate hyperplasia, the spontaneously hypertensive rats (SHR) supplemented with testosterone. METHODS: Three groups of animals (8-week-old; n = 10/group) were considered: Wistar Kyoto (control) rats (WKY), SHR supplemented with testosterone at 3 mg/kg/day and treated with either vehicle (SHR-T, n = 10) or silodosin at 0.1 mg/kg/day (SHR-T + silodosin, n = 10) by oral gavage for 6 weeks. Cystometry experiments were performed. The bladder was harvested, weighed and paraffin-embedded for morphometric analysis. The prostate was also harvested and weighed. RESULTS: The number of animals included in the analysis were n = 10/10 for WKY and n = 7-8/10 for each SHR rats supplemented with testosterone group. SHR-T displayed a significant decrease in the intercontraction interval, infused volume and mean flow rate whereas the frequency of non-voiding contractions was increased. Silodosin improved the voiding behavior of SHR-T by significantly increasing the intercontraction interval, the infused volume and the mean flow rate and decreasing the number of non-voiding contractions. SHR-T displayed a significant increase in prostate and bladder weights and a 15% increase in the detrusor wall area compared to WKY. CONCLUSIONS: Chronic silodosin treatment relieved storage symptoms in SHR supplemented with testosterone and decreased the frequency of non-voiding detrusor contractions during the filling phase.


Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1/uso terapêutico , Indóis/uso terapêutico , Hiperplasia Prostática/tratamento farmacológico , Testosterona/uso terapêutico , Obstrução do Colo da Bexiga Urinária/tratamento farmacológico , Animais , Masculino , Estudo de Prova de Conceito , Hiperplasia Prostática/complicações , Distribuição Aleatória , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Resultado do Tratamento , Obstrução do Colo da Bexiga Urinária/etiologia
8.
Neurotrauma Rep ; 1(1): 125-136, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34223537

RESUMO

The physiopathology of digestive disorders in patients with spinal cord injury (SCI) remains largely unknown, particularly the involvement of the enteric nervous system (ENS). We aimed in a rat model of chronic thoracic SCI to characterize (1) changes in the neurochemical coding of enteric neurons and their putative consequences upon neuromuscular response, and (2) the inflammatory response of the colon. Ex vivo motility of proximal and distal colon segments of SCI and control (CT) rats were studied in an organ chamber in response to electrical field stimulation (EFS) and bethanechol. Immunohistochemical analysis of proximal and distal segments was performed using antibodies again Hu, neuronal nitric oxide synthase, (nNOS), and choline acetyltransferase. Colonic content of acetylcholine and acetylcholinesterase was measured; messenger RNA (mRNA) expression of inflammatory cytokines was measured using reverse transcription quantitative polymerase chain reaction (RT-qPCR) approaches. Compared with the CT rats, the contractile response to bethanechol was significantly decreased in the proximal colon of SCI rats but not in the distal colon. The proportion of nNOS immunoreactive (IR) neurons was significantly reduced in the proximal but not distal colon of SCI rats. No change in proportion of choline acetyltransferase (ChAT)-IR was reported; the tissue concentration of acetylcholine was significantly decreased in the proximal colon of SCI rats. The expression of tumor necrosis factor alpha (TNF-α) and intercellular adhesion molecule-1 (ICAM-1) was significantly reduced in the proximal and distal colon of SCI rats. This study demonstrates that functional motor and enteric neuroplastic changes affect preferentially the proximal colon compared with the distal colon. The underlying mechanisms and factors responsible for these changes remain to be discovered.

9.
J Clin Invest ; 128(6): 2452-2458, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29708508

RESUMO

DEP domain-containing 5 protein (DEPDC5) is a repressor of the recently recognized amino acid-sensing branch of the mTORC1 pathway. So far, its function in the brain remains largely unknown. Germline loss-of-function mutations in DEPDC5 have emerged as a major cause of familial refractory focal epilepsies, with case reports of sudden unexpected death in epilepsy (SUDEP). Remarkably, a fraction of patients also develop focal cortical dysplasia (FCD), a neurodevelopmental cortical malformation. We therefore hypothesized that a somatic second-hit mutation arising during brain development may support the focal nature of the dysplasia. Here, using postoperative human tissue, we provide the proof of concept that a biallelic 2-hit - brain somatic and germline - mutational mechanism in DEPDC5 causes focal epilepsy with FCD. We discovered a mutation gradient with a higher rate of mosaicism in the seizure-onset zone than in the surrounding epileptogenic zone. Furthermore, we demonstrate the causality of a Depdc5 brain mosaic inactivation using CRISPR-Cas9 editing and in utero electroporation in a mouse model recapitulating focal epilepsy with FCD and SUDEP-like events. We further unveil a key role of Depdc5 in shaping dendrite and spine morphology of excitatory neurons. This study reveals promising therapeutic avenues for treating drug-resistant focal epilepsies with mTORC1-targeting molecules.


Assuntos
Epilepsias Parciais , Proteínas Ativadoras de GTPase , Mutação em Linhagem Germinativa , Malformações do Desenvolvimento Cortical , Alvo Mecanístico do Complexo 1 de Rapamicina , Proteínas Repressoras , Animais , Sistemas CRISPR-Cas , Dendritos/metabolismo , Dendritos/patologia , Epilepsias Parciais/genética , Epilepsias Parciais/metabolismo , Epilepsias Parciais/patologia , Feminino , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Humanos , Masculino , Malformações do Desenvolvimento Cortical/genética , Malformações do Desenvolvimento Cortical/metabolismo , Malformações do Desenvolvimento Cortical/patologia , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Camundongos Mutantes , Neurônios/metabolismo , Neurônios/patologia , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Coluna Vertebral/metabolismo , Coluna Vertebral/patologia
10.
Mol Ther Methods Clin Dev ; 5: 200-220, 2017 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-28540323

RESUMO

Mitochondrial dysfunction is responsible for hereditary optic neuropathies. We wished to determine whether preserving mitochondrial bioenergetics could prevent optic neuropathy in a reliable model of glaucoma. DBA/2J mice exhibit elevated intraocular pressure, progressive degeneration of their retinal ganglion cells, and optic neuropathy that resembles glaucoma. We established that glaucoma in these mice is directly associated with mitochondrial dysfunction: respiratory chain activity was compromised in optic nerves 5 months before neuronal loss began, and the amounts of some mitochondrial proteins were reduced in retinas of glaucomatous mice. One of these proteins is neuroglobin, which has a neuroprotective function. Therefore, we investigated whether gene therapy aimed at restoring neuroglobin levels in the retina via ocular administration of an adeno-associated viral vector could reduce neuronal degeneration. The approach of treating 2-month-old mice impeded glaucoma development: few neurons died and respiratory chain activity and visual cortex activity were comparable to those in young, asymptomatic mice. When the treatment was performed in 8-month-old mice, the surviving neurons acquired new morphologic and functional properties, leading to the preservation of visual cortex activity and respiratory chain activity. The beneficial effects of neuroglobin in DBA/2J retinas confirm this protein to be a promising candidate for treating glaucoma.

11.
Neurobiol Dis ; 89: 180-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26873552

RESUMO

DEP-domain containing 5 (DEPDC5), encoding a repressor of the mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway, has recently emerged as a major gene mutated in familial focal epilepsies and focal cortical dysplasia. Here we established a global knockout rat using TALEN technology to investigate in vivo the impact of Depdc5-deficiency. Homozygous Depdc5(-/-) embryos died from embryonic day 14.5 due to a global growth delay. Constitutive mTORC1 hyperactivation was evidenced in the brains and in cultured fibroblasts of Depdc5(-/-) embryos, as reflected by enhanced phosphorylation of its downstream effectors S6K1 and rpS6. Consistently, prenatal treatment with mTORC1 inhibitor rapamycin rescued the phenotype of Depdc5(-/-) embryos. Heterozygous Depdc5(+/-) rats developed normally and exhibited no spontaneous electroclinical seizures, but had altered cortical neuron excitability and firing patterns. Depdc5(+/-) rats displayed cortical cytomegalic dysmorphic neurons and balloon-like cells strongly expressing phosphorylated rpS6, indicative of mTORC1 upregulation, and not observed after prenatal rapamycin treatment. These neuropathological abnormalities are reminiscent of the hallmark brain pathology of human focal cortical dysplasia. Altogether, Depdc5 knockout rats exhibit multiple features of rodent models of mTORopathies, and thus, stand as a relevant model to study their underlying pathogenic mechanisms.


Assuntos
Córtex Cerebral/anormalidades , Modelos Animais de Doenças , Desenvolvimento Embrionário/genética , Complexos Multiproteicos/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Animais Geneticamente Modificados , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/fisiopatologia , Desenvolvimento Embrionário/efeitos dos fármacos , Fibroblastos/metabolismo , Técnicas de Inativação de Genes , Genótipo , Alvo Mecanístico do Complexo 1 de Rapamicina , Complexos Multiproteicos/antagonistas & inibidores , Neurônios/patologia , Neurônios/fisiologia , Fosforilação , Ratos , Ratos Endogâmicos F344 , Ratos Wistar , Proteínas Repressoras/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/administração & dosagem , Serina-Treonina Quinases TOR/antagonistas & inibidores
12.
Toxins (Basel) ; 7(12): 5462-71, 2015 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-26694464

RESUMO

Intradetrusor injections of Botulinum toxin A-currently onabotulinumtoxinA-is registered as a second-line treatment to treat neurogenic detrusor overactivity (NDO). The common clinical practice is 30 × 1 mL injections in the detrusor; however, protocols remain variable and standardization is warranted. The effect of reducing the number of injection sites of Dysport(®) abobotulinumtoxinA (aboBoNTA) was assessed in the spinal cord-injured rat (SCI). Nineteen days post-spinalization, female rats received intradetrusor injections of saline or aboBoNTA 22.5 U distributed among four or eight sites. Two days after injection, continuous cystometry was performed in conscious rats. Efficacy of aboBoNTA 22.5 U was assessed versus aggregated saline groups on clinically-relevant parameters: maximal pressure, bladder capacity, compliance, voiding efficiency, as well as amplitude, frequency, and volume threshold for nonvoiding contractions (NVC). AboBoNTA 22.5 U significantly decreased maximal pressure, without affecting voiding efficiency. Injected in four sites, aboBoNTA significantly increased bladder capacity and compliance while only the latter when in eight sites. AboBoNTA significantly reduced NVC frequency and amplitude. This preclinical investigation showed similar inhibiting effects of aboBoNTA despite the number of sites reduction. Further studies are warranted to optimize dosing schemes to improve the risk-benefit ratio of BoNTA-based treatment modalities for NDO and further idiopathic overactive bladder.


Assuntos
Toxinas Botulínicas Tipo A/administração & dosagem , Fármacos Neuromusculares/administração & dosagem , Traumatismos da Medula Espinal/tratamento farmacológico , Bexiga Urinária Hiperativa/tratamento farmacológico , Animais , Toxinas Botulínicas Tipo A/uso terapêutico , Feminino , Injeções Intramusculares , Fármacos Neuromusculares/uso terapêutico , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/fisiopatologia , Resultado do Tratamento , Bexiga Urinária Hiperativa/fisiopatologia
13.
J Clin Invest ; 125(9): 3642-56, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26301815

RESUMO

Induced pluripotent stem cell-derived (iPS-derived) neural precursor cells may represent the ideal autologous cell source for cell-based therapy to promote remyelination and neuroprotection in myelin diseases. So far, the therapeutic potential of reprogrammed cells has been evaluated in neonatal demyelinating models. However, the repair efficacy and safety of these cells has not been well addressed in the demyelinated adult CNS, which has decreased cell plasticity and scarring. Moreover, it is not clear if these induced pluripotent-derived cells have the same reparative capacity as physiologically committed CNS-derived precursors. Here, we performed a side-by-side comparison of CNS-derived and skin-derived neural precursors in culture and following engraftment in murine models of adult spinal cord demyelination. Grafted induced neural precursors exhibited a high capacity for survival, safe integration, migration, and timely differentiation into mature bona fide oligodendrocytes. Moreover, grafted skin-derived neural precursors generated compact myelin around host axons and restored nodes of Ranvier and conduction velocity as efficiently as CNS-derived precursors while outcompeting endogenous cells. Together, these results provide important insights into the biology of reprogrammed cells in adult demyelinating conditions and support use of these cells for regenerative biomedicine of myelin diseases that affect the adult CNS.


Assuntos
Diferenciação Celular , Doenças Desmielinizantes/terapia , Bainha de Mielina/metabolismo , Células-Tronco Neurais/metabolismo , Pele/metabolismo , Transplante de Células-Tronco , Animais , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/patologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Camundongos , Camundongos Knockout , Células-Tronco Neurais/patologia , Células-Tronco Neurais/transplante , Medicina Regenerativa/métodos , Pele/patologia
14.
Mol Ther ; 22(6): 1096-1109, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24622090

RESUMO

Neuroglobin (NGB) is considered as an endogenous neuroprotective molecule against stroke, since the protein alleviates the adverse effects of hypoxic and ischemic insults. We previously demonstrated the functional link between NGB and mitochondria since it is required for respiratory chain function. Thus, here, we evaluated the relevance of this effect in the Harlequin (Hq) mouse strain, which exhibits retinal ganglion cell (RGC) loss and optic atrophy due to a respiratory chain complex I (CI) defect. A twofold decrease of NGB amounts was observed in Hq retinas. We constructed a recombinant adeno-associated virus which combines to the mouse NGB open reading frame, its 5' and 3'UTR, for guarantying mRNA stability and translation capacity. The vector was administrated intravitreally to Hq mice and NGB expression was stable for up to 7 months without negative effect on retinal architecture or function. On the contrary, RGCs and their axons were substantially preserved from degeneration; consequently, CI activity in optic nerves was protected conferring improvements in vision. Hence, we established that NGB prevents respiratory chain impairment, therefore, protecting visual function otherwise compromised by mitochondrial energetic failure.


Assuntos
Complexo I de Transporte de Elétrons/deficiência , Globinas/genética , Proteínas do Tecido Nervoso/genética , Atrofia Óptica/prevenção & controle , Atrofia Óptica/terapia , Células Ganglionares da Retina/metabolismo , Animais , Axônios/metabolismo , Axônios/patologia , Dependovirus/genética , Modelos Animais de Doenças , Terapia Genética , Vetores Genéticos/administração & dosagem , Gliose/patologia , Gliose/prevenção & controle , Globinas/metabolismo , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Neuroglobina , Atrofia Óptica/genética , Atrofia Óptica/patologia , Células Ganglionares da Retina/patologia
15.
Am J Physiol Regul Integr Comp Physiol ; 306(2): R108-17, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24305064

RESUMO

Despite the fact that urogenito-sexual complications significantly impact the quality of life of diabetic patients, a robust in vivo experimental model is lacking. Bladder and erectile function in the Type 2 diabetic Goto-Kakizaki (GK) rat and responses to standard-of-care treatments for each disorder have been assessed. GK rats (n = 25, 18-wk-old, GK/Par colony) and age-matched Wistar rats (n = 23), characterized for their metabolic parameters, were used. Bladder function was assessed by cystometry in conscious rats treated by intravenous solifenacin (1 mg/kg). Subsequently, erectile function was assessed under anesthesia following electrical stimulation of the cavernous nerve in presence of intravenous sildenafil (0.3 mg/kg). GK rats displayed detrusor overactivity with a significant increase in frequency/amplitude of nonvoiding contractions during the filling phase, together with an increase in bladder capacity, intercontraction interval, voided volume, and maximal pressure of voiding contraction. Solifenacin significantly decreased parameters characterizing voiding contractions without modifying voiding efficiency. Erectile function in GK rats was markedly impaired and remained so after sildenafil treatment despite a significant improvement. GK rats display both bladder and erectile dysfunctions and respond at least partially to standard-of-care treatments for each disorder, thus representing a suitable model to investigate the pathophysiology and assess the efficacy of new therapeutic agents for Type 2 diabetes-associated bladder and erectile complications.


Assuntos
Complicações do Diabetes/fisiopatologia , Diabetes Mellitus Tipo 2/complicações , Disfunção Erétil/etiologia , Doenças da Bexiga Urinária/etiologia , Animais , Diabetes Mellitus Tipo 2/fisiopatologia , Masculino , Ereção Peniana/efeitos dos fármacos , Piperazinas/farmacologia , Purinas/farmacologia , Quinuclidinas/farmacologia , Ratos , Ratos Wistar , Citrato de Sildenafila , Succinato de Solifenacina , Sulfonas/farmacologia , Tetra-Hidroisoquinolinas/farmacologia , Bexiga Urinária/fisiologia , Doenças da Bexiga Urinária/tratamento farmacológico , Doenças da Bexiga Urinária/fisiopatologia , Micção/efeitos dos fármacos , Micção/fisiologia , Agentes Urológicos/farmacologia , Vasodilatadores/farmacologia
16.
Hum Mutat ; 34(10): 1404-14, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24272871

RESUMO

Diffuse bronchiectasis is a common problem in respiratory clinics. We hypothesized that mutations in the solute carrier 26A9 (SLC26A9) gene, encoding for a chloride (Cl(-)) transporter mainly expressed in lungs, may lead to defects in mucociliary clearance. We describe two missense variants in the SLC26A9 gene in heterozygote patients presenting with diffuse idiopathic bronchiectasis : p.Arg575Trp, identified in a patient also heterozygote for p.Phe508del in the CFTR gene; and p.Val486Ile. Expression of both mutants in Xenopus laevis oocytes abolished SLC26A9-mediated Cl(-) conductance without decreasing protein membrane expression. Coexpression of CFTR with SLC26A9-p.Val486Ile resulted in a significant increase in the Cl(-) current induced by PKA stimulation, similar to that obtained in oocytes expressing CFTR and SLC26A9-WT. In contrast, coexpression of CFTR with SLC26A9-p.Arg575Trp inhibited SLC26A9-enhanced CFTR activation upon PKA. Further structure-function analyses led us to propose a site encompassing Arg575 in the SLC26A9-STAS domain for CFTR-SLC26A9 interaction. We hypothesize that SLC26A9-p.Arg575Trp prevented SLC26A9-mediated functional activation of CFTR by altering SLC26A9-CFTR interaction. Although we cannot confirm that these mutations by themselves are deleterious, we propose that they trigger the pathogenic role of a single CFTR mutation and provide insight into a novel mechanism of Cl(-) transport alteration across the respiratory mucosa, based on functional inhibition of CFTR.


Assuntos
Antiporters/genética , Pneumopatias/diagnóstico , Pneumopatias/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antiporters/química , Antiporters/metabolismo , Estudos de Casos e Controles , Criança , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Éxons , Feminino , Expressão Gênica , Humanos , Pneumopatias/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Oócitos/metabolismo , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Fenótipo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Transportadores de Sulfato , Tomografia Computadorizada por Raios X , Xenopus laevis , Adulto Jovem
17.
PLoS One ; 8(3): e57317, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23505426

RESUMO

BACKGROUND: Treatments designed to correct cystic fibrosis transmembrane conductance regulator (CFTR) defects must first be evaluated in preclinical experiments in the mouse model of cystic fibrosis (CF). Mice nasal mucosa mimics the bioelectric defect seen in humans. The use of nasal potential difference (V(TE)) to assess ionic transport is a powerful test evaluating the restoration of CFTR function. Nasal V(TE) in CF mice must be well characterized for correct interpretation. METHODS: We performed V(TE) measurements in large-scale studies of two mouse models of CF--B6;129 cftr knockout and FVB F508del-CFTR--and their respective wild-type (WT) littermates. We assessed the repeatability of the test for cftr knockout mice and defined cutoff points distinguishing between WT and F508del-CFTR mice. RESULTS: We determined the typical V(TE) values for CF and WT mice and demonstrated the existence of residual CFTR activity in F508del-CFTR mice. We characterized intra-animal variability in B6;129 mice and defined the cutoff points for F508del-CFTR chloride secretion rescue. Hyperpolarization of more than -2.15 mV after perfusion with a low-concentration Cl(-) solution was considered to indicate a normal response. CONCLUSIONS: These data will make it possible to interpret changes in nasal V(TE) in mouse models of CF, in future preclinical studies.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Fibrose Cística/genética , Fibrose Cística/metabolismo , Potenciais da Membrana/genética , Mucosa Nasal/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Reprodutibilidade dos Testes
18.
Urology ; 81(5): 1108.e1-6, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23490518

RESUMO

OBJECTIVE: To assess the involvement of connexins (Cxs) 43 and 45 in the selective inhibition of detrusor contractions in patients with neurogenic detrusor overactivity (NDO). MATERIALS AND METHODS: Detrusor strips with and without mucosa were obtained from patients undergoing cystectomy for either neurogenic bladder with NDO refractory to pharmacologic treatment or bladder cancer with no overactive bladder symptoms (ie, control group). The strips were isometrically mounted in organ baths. The effects of the selective inhibitors Cxs 43 and 45 on carbachol-induced contractions of bladder strips were assessed. RESULTS: Overall, 47 patients with a median age of 61 years (range 19-83) were included. The female-to-male ratio was 0.42. Selective inhibitors of Cxs 43 and 45 significantly inhibited carbachol-induced contractions of bladder strips from patient with NDO (P <.01) but had no effect in the control group. When tested without mucosa, the effect of the Cx 43 inhibitor in the NDO patient strips was abolished, but it remained unchanged with the Cx 45 inhibitor (P <.05). CONCLUSION: The pharmacologic modulation of Cx-mediated intercellular communication, targeting Cxs 43 and 45, is directly involved in the functional mechanism of NDO and might represent a future target for the treatment of NDO.


Assuntos
Conexina 43/metabolismo , Conexinas/metabolismo , Contração Muscular/fisiologia , Bexiga Urinaria Neurogênica/metabolismo , Bexiga Urinária Hiperativa/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Bexiga Urinaria Neurogênica/complicações , Bexiga Urinaria Neurogênica/fisiopatologia , Bexiga Urinária Hiperativa/etiologia , Bexiga Urinária Hiperativa/fisiopatologia , Adulto Jovem
19.
Am J Respir Crit Care Med ; 187(2): 170-9, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23220915

RESUMO

RATIONALE: Cystic fibrosis transmembrane conductance regulator (CFTR) protein is a chloride channel regulating fluid homeostasis at epithelial surfaces. Its loss of function induces hypohydration, mucus accumulation, and bacterial infections in CF and potentially other lung chronic diseases. OBJECTIVES: To test whether neutrophil elastase (NE) and neutrophil-mediated inflammation negatively impact CFTR structure and function, in vitro and in vivo. METHODS: Using an adenovirus-CFTR overexpression approach, we showed that NE degrades wild-type (WT)- and ΔF508-CFTR in vitro and WT-CFTR in mice through a new pathway involving the activation of intracellular calpains. MEASUREMENTS AND MAIN RESULTS: CFTR degradation triggered a loss of function, as measured in vitro by channel patch-clamp and in vivo by nasal potential recording in mice. Importantly, this mechanism was also shown to be operative in a Pseudomonas aeruginosa lung infection murine model, and was NE-dependent, because CFTR integrity was significantly protected in NE(-/-) mice compared with WT mice. CONCLUSIONS: These data provide a new mechanism and show for the first time a link between NE-calpains activation and CFTR loss of function in bacterial lung infections relevant to CF and to other chronic inflammatory lung conditions.


Assuntos
Calpaína/fisiologia , Regulador de Condutância Transmembrana em Fibrose Cística/fisiologia , Elastase de Leucócito/fisiologia , Animais , Calpaína/metabolismo , Canais de Cloreto/fisiologia , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Epitélio/fisiologia , Humanos , Elastase de Leucócito/metabolismo , Pulmão/metabolismo , Pulmão/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Patch-Clamp , Pneumonia Bacteriana/etiologia , Pneumonia Bacteriana/fisiopatologia , Infecções por Pseudomonas/etiologia , Infecções por Pseudomonas/fisiopatologia
20.
Sex Med ; 1(2): 35-43, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25356286

RESUMO

INTRODUCTION: Vaginal dryness due to vaginal atrophy is a common complaint of postmenopausal women, interfering with sexual function and quality of life. Hormone replacement therapy is the only effective therapy but with known risks that leave unmet medical needs. A new product, ZP-025 vaginal gel, containing purified (dialyzed lyophilized) bovine colostrum, has been developed for the treatment of vaginal dryness secondary to vaginal atrophy. AIM: The study aims to investigate the effects of intravaginal application of ZP-025 on vaginal atrophy using an animal model. METHODS: Ovariectomized female Sprague-Dawley rats were used. Three weeks after surgery, rats were divided into four groups and treated for 4 weeks (twice a day) with placebo or ZP-025 at low (0.5%) or high (2.3%) concentrations of colostrum; in the control group, rats did not receive any treatment. Changes in vaginal blood flow due to pelvic nerve stimulation were assessed by laser Doppler flowmetry and vaginal tissue was collected for histological assay. MAIN OUTCOME MEASURES: The main outcome measures were vaginal blood flow before and after pelvic nerve stimulation and histology of vaginal epithelium. RESULTS: Treatment with ZP-025 to ovariectomized rats induced an increase of vaginal blood flow parameters (vascular capacitance, amplitude and area under the curve of the response) in response to pelvic nerve stimulation compared with control group, statistically significant at 2.3%. Vaginal epithelium showed a physiological estrous cycle aspect in treated animals, with at least five cell layers vs. one or two cell layers in control rats. As expected from a topical formulation, systemic effects on body weights and uterine wet weights were not observed with application of ZP-025. CONCLUSIONS: In this study, the new product ZP-025, containing purified colostrum, was shown to have beneficial effects on vaginal atrophy in ovariectomized rats, improving vaginal hemodynamics and thickness of vaginal epithelium. Vailati S, Melloni E, Riscassi E, Behr Roussel D, and Sardina M. Evaluation of the effects of a new intravaginal gel, containing purified bovine colostrum, on vaginal blood flow and vaginal atrophy in ovariectomized rat. Sex Med 2013;1:35-43.

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