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1.
Cell ; 181(4): 784-799.e19, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32413299

RESUMO

Swelling of the brain or spinal cord (CNS edema) affects millions of people every year. All potential pharmacological interventions have failed in clinical trials, meaning that symptom management is the only treatment option. The water channel protein aquaporin-4 (AQP4) is expressed in astrocytes and mediates water flux across the blood-brain and blood-spinal cord barriers. Here we show that AQP4 cell-surface abundance increases in response to hypoxia-induced cell swelling in a calmodulin-dependent manner. Calmodulin directly binds the AQP4 carboxyl terminus, causing a specific conformational change and driving AQP4 cell-surface localization. Inhibition of calmodulin in a rat spinal cord injury model with the licensed drug trifluoperazine inhibited AQP4 localization to the blood-spinal cord barrier, ablated CNS edema, and led to accelerated functional recovery compared with untreated animals. We propose that targeting the mechanism of calmodulin-mediated cell-surface localization of AQP4 is a viable strategy for development of CNS edema therapies.


Assuntos
Aquaporina 4/metabolismo , Edema/metabolismo , Edema/terapia , Animais , Aquaporina 4/fisiologia , Astrócitos/metabolismo , Encéfalo/metabolismo , Edema Encefálico/metabolismo , Calmodulina/metabolismo , Sistema Nervoso Central/metabolismo , Edema/fisiopatologia , Masculino , Ratos , Ratos Sprague-Dawley , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/metabolismo , Trifluoperazina/farmacologia
2.
Skin Res Technol ; 29(4): e13311, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37113089

RESUMO

OBJECTIVE: To develop appropriate use criteria (AUC) for the treatment of basal cell and squamous cell carcinoma by superficial radiation therapy (SRT) technique. MATERIAL AND METHODS: Delphi-type discussion of the experts. RESULTS: Presented in Figure 1. CONCLUSION: These AUCs are in compliance both with the position statement of the American Academy of Dermatology (AAD) and the ASTRO Clinical Practice Guideline on this subject. It is further recommended that SRT will be only performed by either a dermatologist who is board certified in Mohs surgery (MDS) and who had adequate SRT training or by radiation oncologists. Hopefully, this publication will stimulate further discussion on this topic.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Cutâneas , Humanos , Estados Unidos , Neoplasias Cutâneas/radioterapia , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/patologia , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas/patologia , Cirurgia de Mohs
3.
Graefes Arch Clin Exp Ophthalmol ; 260(7): 2141-2147, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35080648

RESUMO

PURPOSE: Assess the relationship between photoreceptor degeneration and visual function after retinal reattachment surgery (RRS) in a prospective cohort. METHODS: Patients with rhegmatogenous retinal detachment (RRD) were reviewed before and 6 months after vitreoretinal surgery. Optical coherence tomographical thickness of the outer nuclear layer (ONL), outer retinal segment (ORS), retinal pigmented epithelium to ellipsoid zone (RPE-EZ) and external limiting membrane to EZ (ELM-EZ) were recorded 6 months post-operatively. These were compared to best corrected visual acuity (BCVA) and retinal sensitivity (Humphrey visual field). RESULTS: Thirteen macula-off and 8 macula-on RRD patients were included. The mean ONL thickness was higher after macula-on RRD compared to macula-off RRD (97.70 ± 3.62 µm vs. 73.10 ± 4.98 µm). In all RRD eyes, every 1 µm decrease in ONL thickness correlated with a 0.052 dB decrease and in retinal sensitivity and every 1 µm decrease in ORS thickness was associated with a 0.062 dB reduction in retinal sensitivity. ORS, ELM-EZ and RPE-EZ thickness did not correlate with BCVA post-RRS. CONCLUSION: There was greater ONL and ORS thinning following macula-off compared to macula-on RRD. Correlations between ONL and ORS thinning with decreased retinal sensitivity may be explained by RRD-induced photoreceptor death.


Assuntos
Macula Lutea , Degeneração Retiniana , Descolamento Retiniano , Humanos , Estudos Prospectivos , Retina , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/cirurgia , Estudos Retrospectivos , Tomografia de Coerência Óptica , Acuidade Visual
4.
Int J Mol Sci ; 23(15)2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35955592

RESUMO

In a previous study, we found that administration of ILB®, a new low molecular weight dextran sulphate, significantly improved mitochondrial functions and energy metabolism, as well as decreased oxidative/nitrosative stress, of brain tissue of rats exposed to severe traumatic brain injury (sTBI), induced by the closed-head weight-drop model of diffused TBI. Using aliquots of deproteinized brain tissue of the same animals of this former study, we here determined the concentrations of 24 amino acids of control rats, untreated sTBI rats (sacrificed at 2 and 7 days post-injury) and sTBI rats receiving a subcutaneous ILB® administration (at the dose levels of 1, 5 and 15 mg/kg b.w.) 30 min post-impact (sacrificed at 2 and 7 days post-injury). Additionally, in a different set of experiments, new groups of control rats, untreated sTBI rats and ILB®-treated rats (administered 30 min after sTBI at the dose levels of 1 or 5 mg/kg b.w.) were studied for their neurocognitive functions (anxiety, locomotor capacities, short- and long-term memory) at 7 days after the induction of sTBI. Compared to untreated sTBI animals, ILB® significantly decreased whole brain glutamate (normalizing the glutamate/glutamine ratio), glycine, serine and γ-aminobutyric acid. Furthermore, ILB® administration restored arginine metabolism (preventing nitrosative stress), levels of amino acids involved in methylation reactions (methionine, L-cystathionine, S-adenosylhomocysteine), and N-acetylaspartate homeostasis. The macroscopic evidences of the beneficial effects on brain metabolism induced by ILB® were the relevant improvement in neurocognitive functions of the group of animals treated with ILB® 5 mg/kg b.w., compared to the marked cognitive decline measured in untreated sTBI animals. These results demonstrate that ILB® administration 30 min after sTBI prevents glutamate excitotoxicity and normalizes levels of amino acids involved in crucial brain metabolic functions. The ameliorations of amino acid metabolism, mitochondrial functions and energy metabolism in ILB®-treated rats exposed to sTBI produced significant improvement in neurocognitive functions, reinforcing the concept that ILB® is a new effective therapeutic tool for the treatment of sTBI, worth being tested in the clinical setting.


Assuntos
Lesões Encefálicas Traumáticas , Sulfatos , Aminoácidos/metabolismo , Animais , Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/metabolismo , Sulfato de Dextrana , Ácido Glutâmico , Homeostase , Peso Molecular , Ratos
5.
J Neuroinflammation ; 17(1): 142, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32366307

RESUMO

BACKGROUND: The cornea is innervated with a rich supply of sensory nerves that play important roles in ocular surface health. Any injury or pathology of the corneal nerves increases the risk of dry eye disease and infection. This study aims to evaluate the therapeutic potential of topical decorin to improve corneal nerve regeneration in a mouse model of sterile epithelial abrasion injury. METHODS: Bilateral central corneal epithelial abrasions (2-mm, Alger Brush) were performed on young C57BL/6 J mice to remove the corneal sensory nerves. Decorin, or vehicle, was applied topically, three times per day for 1 week or every 2 h for 6 h. Spectral-domain optical coherence tomography was performed to measure the abrasion area and corneal thickness. Wholemount immunofluorescence staining was used to assess sensory nerve regeneration (ß-tubulin III) and immune cell density (CD45, Iba1, CD11c). To investigate the specific role of dendritic cells (DCs), Cx3cr1gfp/gfp mice, which spontaneously lack resident corneal epithelial DCs, were also investigated. The effect of prophylactic topical administration of recombinant human decorin (applied prior to the abrasion) was also investigated. Nerve tracing (NeuronJ software) was performed to compare recovery of basal nerve axons and superficial nerve terminals in the central and peripheral cornea. RESULTS: At 6 h after injury, topical decorin application was associated with greater intraepithelial DC recruitment but no change in re-epithelialisation or corneal thickness, compared to the vehicle control. One week after injury, sub-basal nerve plexus and superficial nerve terminal density were significantly higher in the central cornea in the decorin-treated eyes. The density of corneal stromal macrophages in the decorin-treated eyes and their contralateral eyes was significantly lower compared to saline-treated corneas. No significant improvement in corneal nerve regeneration was observed in Cx3cr1gfp/gfp mice treated with decorin. CONCLUSIONS: Decorin promotes corneal epithelial nerve regeneration after injury. The neuroregenerative effect of topical decorin was associated with a higher corneal DC density during the acute phase, and fewer macrophages at the study endpoint. The corneal neuroregenerative effects of decorin were absent in mice lacking intraepithelial DCs. Together, these findings support a role for decorin in DC-mediated neuroregeneration following corneal abrasion injury.


Assuntos
Córnea/efeitos dos fármacos , Lesões da Córnea/patologia , Decorina/farmacologia , Regeneração Nervosa/efeitos dos fármacos , Animais , Córnea/inervação , Feminino , Géis , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Nervo Oftálmico/efeitos dos fármacos , Nervo Oftálmico/lesões , Proteínas Recombinantes/farmacologia
6.
Mol Vis ; 24: 712-726, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30429640

RESUMO

Purpose: Elevations in intraocular pressure (IOP) are associated with the development of glaucoma and loss of sight. High transforming growth factor-ß (TGF-ß) 1 levels in the eye's anterior chamber can lead to dysfunctional contractions through RhoA signaling in trabecular meshwork (TM) cells and IOP spikes. Sustained high TGF-ß levels leads to TM fibrosis and sustained increases in IOP. We investigated whether inhibiting RhoA, using a siRNA-mediated RhoA (siRhoA), controls IOP by altering TM expression of fibrosis and contractility-related proteins in a rodent model of glaucoma. Methods: TGF-ß was injected intracamerally twice a week into adult Sprague Dawley rats, and IOP was recorded with tonometry. Animals were euthanized on day 7 and 35 with TM expression of fibrosis and contractility-related proteins, as well as survival of retinal ganglion cells (RGCs) assessed with immunohistochemistry. siRNA against RhoA or enhanced green fluorescent protein (EGFP) was also injected intracamerally into select animals. Successful RhoA knockdown was determined with quantitative reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry, and the effects of the knockdown on the parameters above analyzed. Results: TGF-ß caused increased TM contractile proteins and IOP spikes by day 7, sustained increases in IOP from day 15, and TM fibrosis at day 35. siRhoA abolished the transient 7 day IOP rise but not the later sustained IOP increase (due to fibrosis). At 35 days, TGF-ß-related RGC loss was not prevented with siRhoA treatment. Conclusions: We conclude that RhoA signaling mediates the early IOP rise induced by TM cellular changes associated with contractility but not the sustained IOP elevation caused by TM fibrosis. Thus, RhoA therapies offer a clinically relevant opportunity for IOP management, likely through the modulation of TM contractility, but appear to be ineffective in the amelioration of fibrosis.


Assuntos
Glaucoma de Ângulo Aberto/induzido quimicamente , Pressão Intraocular/efeitos dos fármacos , Interferência de RNA , Malha Trabecular/patologia , Fator de Crescimento Transformador beta1/farmacologia , Proteína rhoA de Ligação ao GTP/metabolismo , Animais , Modelos Animais de Doenças , Fibrose/induzido quimicamente , Glaucoma de Ângulo Aberto/metabolismo , Glaucoma de Ângulo Aberto/patologia , Interferência de RNA/fisiologia , RNA Interferente Pequeno/genética , Ratos , Ratos Sprague-Dawley , Células Ganglionares da Retina/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tonometria Ocular , Malha Trabecular/metabolismo
7.
Stem Cells ; 35(1): 61-67, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27273755

RESUMO

Dental pulp stem cells (DPSC) are neural crest-derived ecto-mesenchymal stem cells that can relatively easily and non-invasively be isolated from the dental pulp of extracted postnatal and adult teeth. Accumulating evidence suggests that DPSC have great promise as a cellular therapy for central nervous system (CNS) and retinal injury and disease. The mode of action by which DPSC confer therapeutic benefit may comprise multiple pathways, in particular, paracrine-mediated processes which involve a wide array of secreted trophic factors and is increasingly regarded as the principal predominant mechanism. In this concise review, we present the current evidence for the use of DPSC to repair CNS damage, including recent findings on retinal ganglion cell neuroprotection and regeneration in optic nerve injury and glaucoma. Stem Cells 2017;35:61-67.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Sistema Nervoso Central/patologia , Polpa Dentária/citologia , Retina/patologia , Células-Tronco/citologia , Cicatrização , Animais , Humanos
8.
Eur J Neurosci ; 56(2): 3783-3785, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35491393
9.
Neurobiol Dis ; 85: 99-110, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26459109

RESUMO

Recent research has suggested that the growth of central nervous system (CNS) axons during development is mediated through the PI3K/Akt/mammalian target of rapamycin (mTOR) intracellular signalling axis and that suppression of activity in this pathway occurs during maturity as levels of the phosphatase and tensin homologue (PTEN) rise and inhibit PI3K activation of mTOR, accounting for the failure of axon regeneration in the injured adult CNS. This hypothesis is supported by findings confirming that suppression of PTEN in experimental adult animals promotes impressive axon regeneration in the injured visual and corticospinal motor systems. This review focuses on these recent developments, discussing the therapeutic potential of a mTOR-based treatment aimed at promoting functional recovery in CNS trauma patients, recognising that to fulfil this ambition, the new therapy should aim to promote not only axon regeneration but also remyelination of regenerated axons, neuronal survival and re-innervation of denervated targets through accurate axonal guidance and synaptogenesis, all with minimal adverse effects. The translational challenges presented by the implementation of this new axogenic therapy are also discussed.


Assuntos
Regeneração Nervosa/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Traumatismos do Sistema Nervoso/fisiopatologia , Traumatismos do Sistema Nervoso/terapia , Animais , Axônios/fisiologia , Humanos
10.
Cytotherapy ; 18(4): 487-96, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26897559

RESUMO

BACKGROUND AIMS: Glaucoma is a leading cause of irreversible blindness involving loss of retinal ganglion cells (RGC). Mesenchymal stromal cells (MSC) have shown promise as a paracrine-mediated therapy for compromised neurons. It is, however, unknown whether dental pulp stem cells (DPSC) are effective as a cellular therapy in glaucoma and how their hypothesized influence compares with other more widely researched MSC sources. The present study aimed to compare the efficacy of adipose-derived stem cells, bone marrow-derived MSC (BMSC) and DPSC in preventing the loss of RGC and visual function when transplanted into the vitreous of glaucomatous rodent eyes. METHODS: Thirty-five days after raised intraocular pressure (IOP) and intravitreal stem cell transplantation, Brn3a(+) RGC numbers, retinal nerve fibre layer thickness (RNFL) and RGC function were evaluated by immunohistochemistry, optical coherence tomography and electroretinography, respectively. RESULTS: Control glaucomatous eyes that were sham-treated with heat-killed DPSC had a significant loss of RGC numbers, RNFL thickness and function compared with intact eyes. BMSC and, to a greater extent, DPSC provided significant protection from RGC loss and RNFL thinning and preserved RGC function. DISCUSSION: The study supports the use of DPSC as a neuroprotective cellular therapy in retinal degenerative disease such as glaucoma.


Assuntos
Glaucoma/patologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/fisiologia , Neuroproteção/fisiologia , Células Ganglionares da Retina/patologia , Células Ganglionares da Retina/fisiologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Eletrorretinografia , Feminino , Humanos , Ratos , Ratos Sprague-Dawley , Retina/patologia , Retina/fisiopatologia , Tomografia de Coerência Óptica
11.
Mol Cell Neurosci ; 68: 212-21, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26260110

RESUMO

Axotomised retinal ganglion cells (RGCs) die rapidly by apoptosis and fail to regenerate because of the limited availability of neurotrophic factors and a lack of axogenic stimuli. However, we have recently showed that pigment epithelium-derived factor (PEDF) promotes RGC survival and axon regeneration after optic nerve crush injury. PEDF has multiple fragments of the native peptide that are neuroprotective, anti-angiogenic and anti-inflammatory. Here we investigated the neuroprotective and axogenic properties of a fragment of PEDF, PEDF-34, in retinal neurons in vitro and when delivered by intravitreal injection and eye drops in vivo. We found that PEDF-34 was 43% more neuroprotective and 52% more neuritogenic than PEDF-44 in vitro. Moreover, in vivo, intravitreal delivery of 1.88nM PEDF-34 was 71% RGC neuroprotective at 21days after optic nerve crush compared to intact controls, whilst daily eye drops containing 1.88nM PEDF-34 promoted 87% RGC survival. After topical eye drop delivery, PEDF-34 was detected in the vitreous body within 30min and attained physiologically relevant concentrations in the retina by 4h peaking at 1.4±0.05nM by 14days. In eye drop- compared to intravitreal-treated PEDF-34 animals, 55% more RGC axons regenerated 250µm beyond the optic nerve lesion. We conclude that daily topical eye drop application of PEDF-34 is superior to weekly intravitreal injections in promoting RGC survival and axon regeneration through both direct effects on retinal neurons and indirect effects on other retinal cells.


Assuntos
Axônios/efeitos dos fármacos , Proteínas do Olho/farmacologia , Fatores de Crescimento Neural/farmacologia , Regeneração Nervosa/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Células Ganglionares da Retina/efeitos dos fármacos , Serpinas/farmacologia , Análise de Variância , Animais , Axônios/fisiologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Proteínas do Olho/metabolismo , Feminino , Proteína GAP-43/metabolismo , Técnicas In Vitro , Injeções Intravítreas , Fatores de Crescimento Neural/metabolismo , Soluções Oftálmicas/uso terapêutico , Traumatismos do Nervo Óptico/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Retina/citologia , Serpinas/metabolismo , Tubulina (Proteína)/metabolismo
12.
Brain ; 137(Pt 6): 1656-75, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24727569

RESUMO

We have previously shown that crushing the optic nerve induces death of retinal ganglion cells by apoptosis, but suppression of CASP2, which is predominantly activated in retinal ganglion cells, using a stably modified short interfering RNA CASP2, inhibits retinal ganglion cell apoptosis. Here, we report that combined delivery of short interfering CASP2 and inhibition of CASP6 using a dominant negative CASP6 mutant activates astrocytes and Müller cells, increases CNTF levels in the retina and leads to enhanced retinal ganglion cell axon regeneration. In dissociated adult rat mixed retinal cultures, dominant negative CASP6 mutant + short interfering CASP2 treatment also significantly increases GFAP+ glial activation, increases the expression of CNTF in culture, and subsequently increases the number of retinal ganglion cells with neurites and the mean retinal ganglion cell neurite length. These effects are abrogated by the addition of MAB228 (a monoclonal antibody targeted to the gp130 component of the CNTF receptor) and AG490 (an inhibitor of the JAK/STAT pathway downstream of CNTF signalling). Similarly, in the optic nerve crush injury model, MAB228 and AG490 neutralizes dominant negative CASP6 mutant + short interfering CASP2-mediated retinal ganglion cell axon regeneration, Müller cell activation and CNTF production in the retina without affecting retinal ganglion cell survival. We therefore conclude that axon regeneration promoted by suppression of CASP2 and CASP6 is CNTF-dependent and mediated through the JAK/STAT signalling pathway. This study offers insights for the development of effective therapeutics for promoting retinal ganglion cell survival and axon regeneration.


Assuntos
Apoptose/efeitos dos fármacos , Axônios/metabolismo , Caspase 2/metabolismo , Caspase 6/metabolismo , Fator Neurotrófico Ciliar/metabolismo , Cisteína Endopeptidases/metabolismo , Células Ganglionares da Retina/metabolismo , Transdução de Sinais , Animais , Apoptose/genética , Modelos Animais de Doenças , Feminino , Regeneração Nervosa/efeitos dos fármacos , Regeneração Nervosa/genética , Regeneração Nervosa/fisiologia , Nervo Óptico/metabolismo , Traumatismos do Nervo Óptico/metabolismo , Ratos , Ratos Sprague-Dawley , Células Ganglionares da Retina/citologia , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
13.
Neurobiol Dis ; 64: 163-76, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24384090

RESUMO

In the injured central nervous system (CNS), transforming growth factor (TGF)-ß1/2-induced scarring and wound cavitation impede axon regeneration implying that a combination of both scar suppression and axogenic treatments is required to achieve functional recovery. After treating acute and chronic dorsal funicular spinal cord lesions (DFL) in adult rats with the pan-TGF-ß1/2 antagonist Decorin, we report that in: (1), acute DFL, the development of all injury parameters was significantly retarded e.g., wound cavity area by 68%, encapsulation of the wound by a glia limitans accessoria (GLA) by 65%, GLA basal lamina thickness by 94%, fibronectin, NG2 and Sema-3A deposition by 87%, 48% and 48%, respectively, and both macrophage and reactive microglia accumulations by 60%; and (2), chronic DFL, all the above parameters were attenuated to a lesser extent e.g., wound cavity area by 11%, GLA encapsulation by 25%, GLA basal lamina thickness by 31%, extracellular fibronectin, NG2 and Sema-3A deposition by 58%, 22% and 29%, respectively, and macrophage and reactive microglia accumulations by 44%. Moreover, in acute and chronic DFL, levels of tissue plasminogen activator (tPA) were raised (by 236% and 482%, respectively), as were active-MMP-2 (by 64% and 91%, respectively) and active-MMP-9 (by 122% and 18%, respectively), while plasminogen activator inhibitor-1 (PAI-1) was suppressed (by 56% and 23%, respectively) and active-TIMP-1 and active TIMP-2 were both lower but only significantly suppressed in acute DFL (by 56 and 21%, respectively). These findings demonstrate that both scar tissue mass and cavitation are attenuated in acute and chronic spinal cord wounds by Decorin treatment and suggest that the dominant effect of Decorin during acute scarring is anti-fibrogenic through suppression of inflammatory fibrosis by neutralisation of TGF-ß1/2 whereas, in chronic lesions, Decorin-induction of tPA and MMP (concomitant with reduced complimentary levels of TIMP and PAI-1) leads to dissolution of the mature established scar by fibrolysis. Decorin also promoted the regeneration of similar numbers of axons through acute and chronic wounds. Accordingly, intrathecal delivery of Decorin offers a potential translatable treatment for scar tissue attenuation in patients with spinal cord injury.


Assuntos
Decorina/farmacologia , Fármacos Neuroprotetores/farmacologia , Traumatismos da Medula Espinal/tratamento farmacológico , Doença Aguda , Animais , Axônios/efeitos dos fármacos , Axônios/patologia , Axônios/fisiologia , Bovinos , Doença Crônica , Cicatriz/tratamento farmacológico , Cicatriz/etiologia , Cicatriz/patologia , Cicatriz/fisiopatologia , Colágeno , Decorina/administração & dosagem , Implantes de Medicamento , Humanos , Masculino , Regeneração Nervosa/efeitos dos fármacos , Regeneração Nervosa/fisiologia , Fármacos Neuroprotetores/administração & dosagem , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta2/antagonistas & inibidores , Fator de Crescimento Transformador beta2/metabolismo
14.
Mol Med ; 20: 147-57, 2014 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-24515258

RESUMO

To characterize the molecular mechanisms of N-acetylaspartate (NAA) metabolism following traumatic brain injury (TBI), we measured the NAA, adenosine triphosphate (ATP) and adenosine diphosphate (ADP) concentrations and calculated the ATP/ADP ratio at different times from impact, concomitantly evaluating the gene and protein expressions controlling NAA homeostasis (the NAA synthesizing and degrading enzymes N-acetyltransferase 8-like and aspartoacylase, respectively) in rats receiving either mild or severe TBI. The reversible changes in NAA induced by mild TBI were due to a combination of transient mitochondrial malfunctioning with energy crisis (decrease in ATP and in the ATP/ADP ratio) and modulation in the gene and protein levels of N-acetyltransferase 8-like and increase of aspartoacylase levels. The irreversible decrease in NAA following severe TBI, was instead characterized by profound mitochondrial malfunctioning (constant 65% decrease of the ATP/ADP indicating permanent impairment of the mitochondrial phosphorylating capacity), dramatic repression of the N-acetyltransferase 8-like gene and concomitant remarkable increase in the aspartoacylase gene and protein levels. The mechanisms underlying changes in NAA homeostasis following graded TBI might be of note for possible new therapeutic approaches and will help in understanding the effects of repeat concussions occurring during particular periods of the complex NAA recovery process, coincident with the so called window of brain vulnerability.


Assuntos
Acetiltransferases/metabolismo , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Amidoidrolases/metabolismo , Ácido Aspártico/análogos & derivados , Lesões Encefálicas/patologia , Acetiltransferases/genética , Amidoidrolases/genética , Animais , Ácido Aspártico/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Lesões Encefálicas/metabolismo , Modelos Animais de Doenças , Masculino , Mitocôndrias/metabolismo , Fosforilação , Ratos , Ratos Wistar
15.
Brain ; 136(Pt 9): 2842-58, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23983032

RESUMO

In post-haemorrhagic and other forms of communicating hydrocephalus, cerebrospinal fluid flow and drainage is obstructed by subarachnoid fibrosis in which the potent fibrogenic cytokine transforming growth factor-ß has been aetiologically implicated. Here, the hypothesis that the transforming growth factor-ß antagonist decorin has therapeutic potential for reducing fibrosis and ventriculomegaly was tested using a rat model of juvenile communicating hydrocephalus. Hydrocephalus was induced by a single basal cistern injection of kaolin in 3-week-old rats, immediately followed by 3 or 14 days of continuous intraventricular infusion of either human recombinant decorin or phosphate-buffered saline (vehicle). Ventricular expansion was measured by magnetic resonance imaging at Day 14. Fibrosis, transforming growth factor-ß/Smad2/3 activation and hydrocephalic brain pathology were evaluated at Day 14 and the inflammatory response at Days 3 and 14 by immunohistochemistry and basic histology. Analysis of ventricular size demonstrated the development of hydrocephalus in kaolin-injected rats but also revealed that continuous decorin infusion prevented ventricular enlargement, such that ventricle size remained similar to that in intact control rats. Decorin prevented the increase in transforming growth factor-ß1 and phosphorylated Smad2/3 levels throughout the ventricular system after kaolin injection and also inhibited the deposition of the extracellular matrix molecules, laminin and fibronectin in the subarachnoid space. In addition, decorin protected against hydrocephalic brain damage inferred from attenuation of glial and inflammatory reactions. Thus, we conclude that decorin prevented the development of hydrocephalus in juvenile rats by blocking transforming growth factor-ß-induced subarachnoid fibrosis and protected against hydrocephalic brain damage. The results suggest that decorin is a potential clinical therapeutic for the treatment of juvenile post-haemorrhagic communicating hydrocephalus.


Assuntos
Decorina/uso terapêutico , Hidrocefalia/prevenção & controle , Análise de Variância , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Antígeno CD11b/metabolismo , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Epêndima/efeitos dos fármacos , Epêndima/patologia , Fibronectinas/metabolismo , Fibrose/etiologia , Fibrose/prevenção & controle , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Hidrocefalia/induzido quimicamente , Hidrocefalia/patologia , Caulim/toxicidade , Imageamento por Ressonância Magnética , Ratos , Ratos Sprague-Dawley , Recombinases Rec A/metabolismo , Proteína Smad2/metabolismo , Espaço Subaracnóideo/patologia , Fatores de Tempo , Fator de Crescimento Transformador beta1/metabolismo
16.
Sci Rep ; 14(1): 9643, 2024 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-38670997

RESUMO

Optical coherence tomography angiography (OCTA) is widely used for non-invasive retinal vascular imaging, but the OCTA methods used to assess retinal perfusion vary. We evaluated the different methods used to assess retinal perfusion between OCTA studies. MEDLINE and Embase were searched from 2014 to August 2021. We included prospective studies including ≥ 50 participants using OCTA to assess retinal perfusion in either global retinal or systemic disorders. Risk of bias was assessed using the National Institute of Health quality assessment tool for observational cohort and cross-sectional studies. Heterogeneity of data was assessed by Q statistics, Chi-square test, and I2 index. Of the 5974 studies identified, 191 studies were included in this evaluation. The selected studies employed seven OCTA devices, six macula volume dimensions, four macula subregions, nine perfusion analyses, and five vessel layer definitions, totalling 197 distinct methods of assessing macula perfusion and over 7000 possible combinations. Meta-analysis was performed on 88 studies reporting vessel density and foveal avascular zone area, showing lower retinal perfusion in patients with diabetes mellitus than in healthy controls, but with high heterogeneity. Heterogeneity was lowest and reported vascular effects strongest in superficial capillary plexus assessments. Systematic review of OCTA studies revealed massive heterogeneity in the methods employed to assess retinal perfusion, supporting calls for standardisation of methodology.


Assuntos
Vasos Retinianos , Tomografia de Coerência Óptica , Tomografia de Coerência Óptica/métodos , Humanos , Vasos Retinianos/diagnóstico por imagem , Angiofluoresceinografia/métodos , Angiografia/métodos
17.
PLoS One ; 19(7): e0291285, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38990927

RESUMO

BACKGROUND: Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig´s disease, is a rare neurological condition and is the most common motor neurone disease. It is a fatal disease with specific loss of motor neurons in the spinal cord, brain stem, and motor cortex leading to progressive paralysis and usually death within five years of diagnosis. There remains no cure for ALS, and management is focused on a combination of neuroprotective medication, respiratory support, and management by multidisciplinary clinics. PATIENTS AND METHODS: This prospective, single-arm, open-label phase II clinical trial of sustained weekly administration of 2 mg/kg ILB® (a low-molecular weight dextran sulphate) was conducted in a single UK hospital. Eligible patients were at least 18 years and had a definite diagnosis of ALS according to El Escorial Criteria. The co-primary outcomes were safety, tolerability, and quantity of ILB® administered. EudraCT number. 2018-000668-28. FINDINGS: Between 18-Apr-2019 and 27-Mar-2020, 11 patients were recruited and treated for up to 38 weeks. There were no treatment terminations or withdrawals. One serious adverse event was reported, which was not related to ILB® and resolved without sequalae. 270 mild/moderate adverse events were reported with no intolerable events occurring during the trial. The total number of ILB® treatments administered per patient ranged from 4 to 38, with a cumulative dose ranging from 745 to 6668 mg. As a result of the COVID-19 pandemic and the high-risk status of study participants, recruitment and treatment was suspended early in Mar-2020. At the long-term follow-up, three patients had died after the trial was halted, between 53 and 62 weeks after their final ILB® injection. INTERPRETATION: Long-term weekly ILB® injections of 2 mg/kg was well tolerated and had an acceptable safety profile in patients with ALS. TRIAL REGISTRATION: EudraCT: 2018-000668-28. clinicaltrials.gov: NCT03705390. This trial adheres to the principles of GCP in the design, conduct, recording and reporting of clinical trials as listed in part 2, "Conditions and Principles which apply to all Clinical Trials" under the header "Principles based on Articles 2 to 5 of the EU GCP Directive" in the Medicines for Human Use Clinical Trials Regulations (as amended in SI 2006/1928). For clarity, the study did not conform to all aspects of the International Conference on Harmonisation (ICH) E6 R2 Guidelines for GCP (also known as 'ICH GCP'). Of note, we did not use an external database, perform 100% source data verification, and only primary outcome data were analysed in parallel by a second, independent statistician.


Assuntos
Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/tratamento farmacológico , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , Resultado do Tratamento , Adulto , Fármacos Neuroprotetores/uso terapêutico , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/efeitos adversos
18.
Ophthalmology ; 120(8): 1588-91, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23618228

RESUMO

OBJECTIVE: To describe the prognosis and retinal location in patients presenting with acute traumatic maculopathy and extramacular retinal injuries. DESIGN: Retrospective, noninterventional case series. PARTICIPANTS AND CONTROLS: All patients presenting with commotio retinae or sclopetaria retinae to the Birmingham Midland Eye Centre Eye Casualty from October 1, 2007, to February 23, 2011. METHODS: The notes of all patients presenting with ocular trauma in the specified time period were examined to identify suitable patients and demographic and injury data were extracted. MAIN OUTCOME MEASURES: Outcome was assessed by visual acuity (VA). RESULTS: For macular commotio retinae, 53 patients were identified, of whom 34 had adequate follow-up to determine final VA. The median presenting VA was 20/40; 25 patients (74%) recovered to ≥ 20/30. The median extent of visual recovery was 0.18 logarithm of the minimum angle of resolution (logMAR). For extramacular commotio retinae, 117 patients were identified, of whom 58 had adequate follow-up to determine final VA. The median presenting VA retinae was 20/30; 55 patients (95%) recovered to ≥ 20/30. The median extent of visual recovery was logMAR 0.076. There was 1 case of extramacular sclopetaria retinae. The 3 most common retinal locations of extramacular commotio retinae, in order of frequency, were inferotemporal (37%), temporal (17%), and superotemporal (17%); <5% of cases were in a nasal location. CONCLUSIONS: This is the first report on the prognosis of acute traumatic maculopathy and extramacular commotio retinae. After macular injury, 26% of patients were left with a VA of ≤ 20/30, although the proportion with visual impairment is higher than this because (1) a deterioration from 20/15 to 20/30 is significant to many patients; and (2) additional patients are visually impaired by symptomatic paracentral visual field defects despite a normal VA. Reduced VA after extramacular commotio retinae may represent occult macular injury or previously undiagnosed visual impairment in the affected eye. Extramacular commotio occurs mostly in an inferotemporal to temporal location, consistent with direct trauma to the sclera overlying the injured retina. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any of the materials discussed in this article.


Assuntos
Traumatismos Oculares/fisiopatologia , Retina/lesões , Doenças Retinianas/fisiopatologia , Acuidade Visual/fisiologia , Ferimentos não Penetrantes/fisiopatologia , Adulto , Traumatismos Oculares/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Prognóstico , Doenças Retinianas/diagnóstico , Estudos Retrospectivos , Tomografia de Coerência Óptica , Resultado do Tratamento , Transtornos da Visão/diagnóstico , Transtornos da Visão/fisiopatologia , Campos Visuais/fisiologia , Ferimentos não Penetrantes/diagnóstico , Adulto Jovem
19.
Mol Cell Neurosci ; 49(4): 464-74, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22425560

RESUMO

Adeno-associated viral vectors (AAV) are increasingly used to deliver therapeutic genes to the central nervous system (CNS) where they promote transgene expression in post mitotic neurones for long periods with little or no toxicity. In adult rat dorsal root ganglia (DRG), we investigated the cellular tropism of AAV8 containing the green fluorescent protein gene (gfp) after either intra-lumbar DRG or intrathecal injection and showed that transduced DRG neurones (DRGN) expressed GFP irrespective of the delivery route, while non-neuronal cells were GFP(-). After intra-DRG delivery of AAV8(gfp), the mean DRGN transduction rate was 11%, while intrathecal delivery transduced a mean of 1.5% DRGN. After intra-DRG injection, 2% of small DRGN (<30 µm in diameter) were GFP(+) compared with 32% of large DRGN (>60 µm in diameter). Axons of transduced DRGN were also GFP(+); no intra-spinal neurones were transduced. A small number of contralateral DRGN were transduced after intra-DRG injection, suggesting that AAV8 may diffuse from injected DRG into the spinal canal. Microglia and astrocytes were highly ramified with increased GFAP(+) immunoreactivity (i.e. activated) in the neuropil around GFP(+) DRG axon projections within the cord after intra-DRG injection. This study showed that after both intra-DRG and intrathecal delivery, strong preferential AAV8 tropism exists for large DRGN unassociated with cell death, but GFP(+) axons projecting in the spinal cord induced local glial activation. These results open up opportunities for targeted delivery of therapeutics such as neurotrophic factors to the injured spinal cord.


Assuntos
Dependovirus/fisiologia , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Neurônios/virologia , Transdução Genética/métodos , Animais , Gânglios Espinais/virologia , Proteínas de Fluorescência Verde/administração & dosagem , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Injeções Espinhais , Ratos
20.
Life (Basel) ; 13(12)2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38137838

RESUMO

Wet age-related macular degeneration (wAMD) is a chronic inflammation-associated neurodegenerative disease affecting the posterior part of the eye in the aging population. Aging results in the reduced functionality of cells and tissues, including the cells of the retina. Initiators of a chronic inflammatory and pathologic state in wAMD may be a result of the accumulation of inevitable metabolic injuries associated with the maintenance of tissue homeostasis from a young age to over 50. Apart from this, risk factors like smoking, genetic predisposition, and failure to repair the injuries that occur, alongside attempts to rescue the hypoxic outer retina may also contribute to the pathogenesis. Aging of the immune system (immunosenescence) and a compromised outer blood retinal barrier (BRB) result in the exposure of the privileged milieu of the retina to the systemic immune system, further increasing the severity of the disease. When immune-privileged sites like the retina are under pathological stress, certain age- and disease-related conditions may necessitate assistance from cells distant from the resident ones to help restore the functionality of the tissue. As a necessary part of tissue repair, inflammation is a major response to disease and recruits immune cells to the site of damage. We suspect that the specific reparative inflammatory responses are controlled by an autoantigen-T cell-mediated mechanism, a process that may be hindered in wAMD.

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