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1.
Cell ; 181(4): 784-799.e19, 2020 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-32413299

RESUMEN

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.


Asunto(s)
Acuaporina 4/metabolismo , Edema/metabolismo , Edema/terapia , Animales , Acuaporina 4/fisiología , Astrocitos/metabolismo , Encéfalo/metabolismo , Edema Encefálico/metabolismo , Calmodulina/metabolismo , Sistema Nervioso Central/metabolismo , Edema/fisiopatología , Masculino , Ratas , Ratas Sprague-Dawley , Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/metabolismo , Trifluoperazina/farmacología
2.
Skin Res Technol ; 29(4): e13311, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37113089

RESUMEN

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.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Cutáneas , Humanos , Estados Unidos , Neoplasias Cutáneas/radioterapia , Neoplasias Cutáneas/cirugía , Neoplasias Cutáneas/patología , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirugía , Carcinoma de Células Escamosas/patología , Cirugía de Mohs
3.
Graefes Arch Clin Exp Ophthalmol ; 260(7): 2141-2147, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35080648

RESUMEN

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.


Asunto(s)
Mácula Lútea , Degeneración Retiniana , Desprendimiento de Retina , Humanos , Estudios Prospectivos , Retina , Desprendimiento de Retina/diagnóstico , Desprendimiento de Retina/cirugía , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Agudeza Visual
4.
Int J Mol Sci ; 23(15)2022 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-35955592

RESUMEN

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.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Sulfatos , Aminoácidos/metabolismo , Animales , Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Lesiones Traumáticas del Encéfalo/metabolismo , Sulfato de Dextran , Ácido Glutámico , Homeostasis , Peso Molecular , Ratas
5.
J Neuroinflammation ; 17(1): 142, 2020 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-32366307

RESUMEN

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.


Asunto(s)
Córnea/efectos de los fármacos , Lesiones de la Cornea/patología , Decorina/farmacología , Regeneración Nerviosa/efectos de los fármacos , Animales , Córnea/inervación , Femenino , Geles , Humanos , Ratones , Ratones Endogámicos C57BL , Nervio Oftálmico/efectos de los fármacos , Nervio Oftálmico/lesiones , Proteínas Recombinantes/farmacología
6.
Mol Vis ; 24: 712-726, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30429640

RESUMEN

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.


Asunto(s)
Glaucoma de Ángulo Abierto/inducido químicamente , Presión Intraocular/efectos de los fármacos , Interferencia de ARN , Malla Trabecular/patología , Factor de Crecimiento Transformador beta1/farmacología , Proteína de Unión al GTP rhoA/metabolismo , Animales , Modelos Animales de Enfermedad , Fibrosis/inducido químicamente , Glaucoma de Ángulo Abierto/metabolismo , Glaucoma de Ángulo Abierto/patología , Interferencia de ARN/fisiología , ARN Interferente Pequeño/genética , Ratas , Ratas Sprague-Dawley , Células Ganglionares de la Retina/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tonometría Ocular , Malla Trabecular/metabolismo
7.
Stem Cells ; 35(1): 61-67, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27273755

RESUMEN

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.


Asunto(s)
Tratamiento Basado en Trasplante de Células y Tejidos , Sistema Nervioso Central/patología , Pulpa Dental/citología , Retina/patología , Células Madre/citología , Cicatrización de Heridas , Animales , Humanos
8.
Eur J Neurosci ; 56(2): 3783-3785, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35491393
9.
Neurobiol Dis ; 85: 99-110, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26459109

RESUMEN

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.


Asunto(s)
Regeneración Nerviosa/fisiología , Serina-Treonina Quinasas TOR/metabolismo , Traumatismos del Sistema Nervioso/fisiopatología , Traumatismos del Sistema Nervioso/terapia , Animales , Axones/fisiología , Humanos
10.
Cytotherapy ; 18(4): 487-96, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26897559

RESUMEN

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.


Asunto(s)
Glaucoma/patología , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/fisiología , Neuroprotección/fisiología , Células Ganglionares de la Retina/patología , Células Ganglionares de la Retina/fisiología , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Electrorretinografía , Femenino , Humanos , Ratas , Ratas Sprague-Dawley , Retina/patología , Retina/fisiopatología , Tomografía de Coherencia Óptica
11.
Mol Cell Neurosci ; 68: 212-21, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26260110

RESUMEN

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.


Asunto(s)
Axones/efectos de los fármacos , Proteínas del Ojo/farmacología , Factores de Crecimiento Nervioso/farmacología , Regeneración Nerviosa/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Células Ganglionares de la Retina/efectos de los fármacos , Serpinas/farmacología , Análisis de Varianza , Animales , Axones/fisiología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Proteínas del Ojo/metabolismo , Femenino , Proteína GAP-43/metabolismo , Técnicas In Vitro , Inyecciones Intravítreas , Factores de Crecimiento Nervioso/metabolismo , Soluciones Oftálmicas/uso terapéutico , Traumatismos del Nervio Óptico/tratamiento farmacológico , Ratas , Ratas Sprague-Dawley , Retina/citología , Serpinas/metabolismo , Tubulina (Proteína)/metabolismo
12.
Brain ; 137(Pt 6): 1656-75, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24727569

RESUMEN

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.


Asunto(s)
Apoptosis/efectos de los fármacos , Axones/metabolismo , Caspasa 2/metabolismo , Caspasa 6/metabolismo , Factor Neurotrófico Ciliar/metabolismo , Cisteína Endopeptidasas/metabolismo , Células Ganglionares de la Retina/metabolismo , Transducción de Señal , Animales , Apoptosis/genética , Modelos Animales de Enfermedad , Femenino , Regeneración Nerviosa/efectos de los fármacos , Regeneración Nerviosa/genética , Regeneración Nerviosa/fisiología , Nervio Óptico/metabolismo , Traumatismos del Nervio Óptico/metabolismo , Ratas , Ratas Sprague-Dawley , Células Ganglionares de la Retina/citología , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Transducción de Señal/fisiología
13.
Neurobiol Dis ; 64: 163-76, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24384090

RESUMEN

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.


Asunto(s)
Decorina/farmacología , Fármacos Neuroprotectores/farmacología , Traumatismos de la Médula Espinal/tratamiento farmacológico , Enfermedad Aguda , Animales , Axones/efectos de los fármacos , Axones/patología , Axones/fisiología , Bovinos , Enfermedad Crónica , Cicatriz/tratamiento farmacológico , Cicatriz/etiología , Cicatriz/patología , Cicatriz/fisiopatología , Colágeno , Decorina/administración & dosificación , Implantes de Medicamentos , Humanos , Masculino , Regeneración Nerviosa/efectos de los fármacos , Regeneración Nerviosa/fisiología , Fármacos Neuroprotectores/administración & dosificación , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/farmacología , Médula Espinal/efectos de los fármacos , Médula Espinal/patología , Médula Espinal/fisiopatología , Traumatismos de la Médula Espinal/complicaciones , Traumatismos de la Médula Espinal/patología , Traumatismos de la Médula Espinal/fisiopatología , Factor de Crecimiento Transformador beta1/antagonistas & inhibidores , Factor de Crecimiento Transformador beta1/metabolismo , Factor de Crecimiento Transformador beta2/antagonistas & inhibidores , Factor de Crecimiento Transformador beta2/metabolismo
14.
Mol Med ; 20: 147-57, 2014 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-24515258

RESUMEN

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.


Asunto(s)
Acetiltransferasas/metabolismo , Adenosina Difosfato/metabolismo , Adenosina Trifosfato/metabolismo , Amidohidrolasas/metabolismo , Ácido Aspártico/análogos & derivados , Lesiones Encefálicas/patología , Acetiltransferasas/genética , Amidohidrolasas/genética , Animales , Ácido Aspártico/metabolismo , Encéfalo/metabolismo , Encéfalo/patología , Lesiones Encefálicas/metabolismo , Modelos Animales de Enfermedad , Masculino , Mitocondrias/metabolismo , Fosforilación , Ratas , Ratas Wistar
15.
Brain ; 136(Pt 9): 2842-58, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23983032

RESUMEN

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.


Asunto(s)
Decorina/uso terapéutico , Hidrocefalia/prevención & control , Análisis de Varianza , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Antígeno CD11b/metabolismo , Modelos Animales de Enfermedad , Sistemas de Liberación de Medicamentos , Epéndimo/efectos de los fármacos , Epéndimo/patología , Fibronectinas/metabolismo , Fibrosis/etiología , Fibrosis/prevención & control , Proteína Ácida Fibrilar de la Glía/metabolismo , Humanos , Hidrocefalia/inducido químicamente , Hidrocefalia/patología , Caolín/toxicidad , Imagen por Resonancia Magnética , Ratas , Ratas Sprague-Dawley , Rec A Recombinasas/metabolismo , Proteína Smad2/metabolismo , Espacio Subaracnoideo/patología , Factores de Tiempo , Factor de Crecimiento Transformador beta1/metabolismo
16.
Sci Rep ; 14(1): 21312, 2024 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-39266635

RESUMEN

To investigate if retinal thickness has predictive utility in COVID-19 outcomes by evaluating the statistical association between retinal thickness using OCT and of COVID-19-related mortality. Secondary outcomes included associations between retinal thickness and length of stay (LoS) in hospital. In this retrospective cohort study, OCT scans from 230 COVID-19 patients admitted to the Intensive Care Unit (ITU) were compared with age and gender-matched patients with pneumonia from before March 2020. Total retinal, GCL + IPL, and RNFL thicknesses were recorded, and analysed with systemic measures collected at the time of admission and mortality outcomes, using linear regression models, Pearson's R correlation, and Principal Component Analysis. Retinal thickness was significantly associated with all-time mortality on follow up in the COVID-19 group (p = 0.015), but not 28-day mortality (p = 0.151). Retinal and GCL + IPL layer thicknesses were both significantly associated with LoS in hospital for COVID-19 patients (p = 0.006 for both), but not for patients with pneumonia (p = 0.706 and 0.989 respectively). RNFL thickness was not associated with LoS in either group (COVID-19 p = 0.097, pneumonia p = 0.692). Retinal thickness associated with LoS in hospital and long-term mortality in COVID-19 patients, suggesting that retinal structure could be a surrogate marker for frailty and predictor of disease severity in this group of patients, but not in patients with pneumonia from other causes.


Asunto(s)
COVID-19 , Unidades de Cuidados Intensivos , Retina , Tomografía de Coherencia Óptica , Humanos , COVID-19/mortalidad , COVID-19/patología , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Retina/patología , Retina/diagnóstico por imagen , Anciano , Tomografía de Coherencia Óptica/métodos , Tiempo de Internación , SARS-CoV-2/aislamiento & purificación , Hospitalización
17.
Sci Rep ; 14(1): 9643, 2024 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-38670997

RESUMEN

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.


Asunto(s)
Vasos Retinianos , Tomografía de Coherencia Óptica , Tomografía de Coherencia Óptica/métodos , Humanos , Vasos Retinianos/diagnóstico por imagen , Angiografía con Fluoresceína/métodos , Angiografía/métodos
18.
PLoS One ; 19(7): e0291285, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38990927

RESUMEN

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.


Asunto(s)
Esclerosis Amiotrófica Lateral , Humanos , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Masculino , Femenino , Persona de Mediana Edad , Anciano , Estudios Prospectivos , Resultado del Tratamiento , Adulto , Fármacos Neuroprotectores/uso terapéutico , Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/efectos adversos
19.
Ophthalmology ; 120(8): 1588-91, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23618228

RESUMEN

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.


Asunto(s)
Lesiones Oculares/fisiopatología , Retina/lesiones , Enfermedades de la Retina/fisiopatología , Agudeza Visual/fisiología , Heridas no Penetrantes/fisiopatología , Adulto , Lesiones Oculares/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Pronóstico , Enfermedades de la Retina/diagnóstico , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Resultado del Tratamiento , Trastornos de la Visión/diagnóstico , Trastornos de la Visión/fisiopatología , Campos Visuales/fisiología , Heridas no Penetrantes/diagnóstico , Adulto Joven
20.
Mol Cell Neurosci ; 49(4): 464-74, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22425560

RESUMEN

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.


Asunto(s)
Dependovirus/fisiología , Terapia Genética/métodos , Vectores Genéticos/administración & dosificación , Neuronas/virología , Transducción Genética/métodos , Animales , Ganglios Espinales/virología , Proteínas Fluorescentes Verdes/administración & dosificación , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Inyecciones Espinales , Ratas
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