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1.
ACS Appl Mater Interfaces ; 16(10): 12437-12445, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38436945

RESUMEN

Rising global energy demand, accompanied by environmental concerns linked to conventional fossil fuels, necessitates a shift toward cleaner and sustainable alternatives. This study focuses on the machine-learning (ML)-driven high-throughput screening of transition-metal (TM) atom intercalated g-C3N4/MX2 (M = Mo, W; X = S, Se, Te) heterostructures to unravel the rich landscape of possibilities for enhancing the hydrogen evolution reaction (HER) activity. The stability of the heterostructures and the intercalation within the substrates are verified through adhesion and binding energies, showcasing the significant impact of chalcogenide selection on the interaction properties. Based on hydrogen adsorption Gibbs free energy (ΔGH) computed via density functional theory (DFT) calculations, several ML models were evaluated, particularly random forest regression (RFR) emerges as a robust tool in predicting HER activity with a low mean absolute error (MAE) of 0.118 eV, thereby paving the way for accelerated catalyst screening. The Shapley Additive exPlanation (SHAP) analysis elucidates pivotal descriptors that influence the HER activity, including hydrogen adsorption on the C site (HC), MX layer (HMX), S site (HS), and intercalation of TM atoms at the N site (IN). Overall, our integrated approach utilizing DFT and ML effectively identifies hydrogen adsorption on the N site (site-3) of g-C3N4 as a pivotal active site, showcasing exceptional HER activity in heterostructures intercalated with Sc and Ti, underscoring their potential for advancing catalytic performance.

2.
J Biol Chem ; 300(4): 107172, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38499151

RESUMEN

The recently discovered interaction between Presenilin 1 (PS1), a catalytic subunit of γ-secretase responsible for generating amyloid-ß peptides, and GLT-1, a major glutamate transporter in the brain (EAAT2), provides a mechanistic link between these two key factors involved in Alzheimer's disease (AD) pathology. Modulating this interaction can be crucial to understand the consequence of such crosstalk in AD context and beyond. However, the interaction sites between these two proteins are unknown. Herein, we utilized an alanine scanning approach coupled with FRET-based fluorescence lifetime imaging microscopy to identify the interaction sites between PS1 and GLT-1 in their native environment within intact cells. We found that GLT-1 residues at position 276 to 279 (TM5) and PS1 residues at position 249 to 252 (TM6) are crucial for GLT-1-PS1 interaction. These results have been cross validated using AlphaFold Multimer prediction. To further investigate whether this interaction of endogenously expressed GLT-1 and PS1 can be prevented in primary neurons, we designed PS1/GLT-1 cell-permeable peptides (CPPs) targeting the PS1 or GLT-1 binding site. We used HIV TAT domain to allow for cell penetration which was assayed in neurons. First, we assessed the toxicity and penetration of CPPs by confocal microscopy. Next, to ensure the efficiency of CPPs, we monitored the modulation of GLT-1-PS1 interaction in intact neurons by fluorescence lifetime imaging microscopy. We saw significantly less interaction between PS1 and GLT-1 with both CPPs. Our study establishes a new tool to study the functional aspect of GLT-1-PS1 interaction and its relevance in normal physiology and AD models.


Asunto(s)
Transportador 2 de Aminoácidos Excitadores , Presenilina-1 , Animales , Humanos , Ratones , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Secretasas de la Proteína Precursora del Amiloide/genética , Sitios de Unión , Transportador 2 de Aminoácidos Excitadores/química , Transportador 2 de Aminoácidos Excitadores/genética , Transportador 2 de Aminoácidos Excitadores/metabolismo , Transferencia Resonante de Energía de Fluorescencia , Células HEK293 , Neuronas/metabolismo , Presenilina-1/química , Presenilina-1/genética , Presenilina-1/metabolismo , Unión Proteica , Péptidos/metabolismo
3.
Res Sq ; 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37986905

RESUMEN

The recently discovered interaction between presenilin 1 (PS1), a catalytic subunit of γ-secretase responsible for the generation of amyloid-ß(Aß) peptides, and GLT-1, the major glutamate transporter in the brain (EAAT2 in the human) may provide a mechanistic link between two important pathological aspects of Alzheimer's disease (AD): abnormal Aßoccurrence and neuronal network hyperactivity. In the current study, we employed a FRET-based approach, fluorescence lifetime imaging microscopy (FLIM), to characterize the PS1/GLT-1 interaction in its native environment in the brain tissue of sporadic AD (sAD) patients. There was significantly less interaction between PS1 and GLT-1 in sAD brains, compared to tissue from patients with frontotemporal lobar degeneration (FTLD), or non-demented age-matched controls. Since PS1 has been shown to adopt pathogenic "closed" conformation in sAD but not in FTLD, we assessed the impact of changes in PS1 conformation on the interaction. Familial AD (fAD) PS1 mutations which induce a "closed" PS1 conformation similar to that in sAD brain and gamma-secretase modulators (GSMs) which induce a "relaxed" conformation, reduced and increased the interaction, respectively. This indicates that PS1 conformation seems to have a direct effect on the interaction with GLT-1. Furthermore, using biotinylation/streptavidin pull-down, western blotting, and cycloheximide chase assays, we determined that the presence of PS1 increased GLT-1 cell surface expression and GLT-1 homomultimer formation, but did not impact GLT-1 protein stability. Together, the current findings suggest that the newly described PS1/GLT-1 interaction endows PS1 with chaperone activity, modulating GLT-1 transport to the cell surface and stabilizing the dimeric-trimeric states of the protein. The diminished PS1/GLT-1 interaction suggests that these functions of the interaction may not work properly in AD.

4.
bioRxiv ; 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37398024

RESUMEN

The recently discovered interaction between Presenilin 1 (PS1), a catalytic subunit of γ-secretase responsible for generating amyloid-ß (Aß) peptides, and GLT-1, a major glutamate transporter in the brain (EAAT2) provides a mechanistic link between these two key factors involved in Alzheimer's disease (AD) pathology. Modulating this interaction can be crucial to understand the consequence of such crosstalk in AD context and beyond. However, the interaction sites between these two proteins are unknown. Herein, we utilized an alanine scanning approach coupled with FRET-based fluorescence lifetime imaging microscopy (FLIM) to identify the interaction sites between PS1 and GLT-1 in their native environment within intact cells. We found that GLT-1 residues at position 276 to 279 (TM5) and PS1 residues at position 249 to 252 (TM6) are crucial for GLT-1/PS1 interaction. These results have been cross validated using AlphaFold Multimer prediction. To further investigate whether this interaction of endogenously expressed GLT-1 and PS1 can be prevented in primary neurons, we designed PS1/GLT-1 cell-permeable peptides (CPPs) targeting the PS1 or GLT-1 binding site. We used HIV TAT domain to allow for cell penetration which was assayed in neurons. First, we assessed the toxicity and penetration of CPPs by confocal microscopy. Next, to ensure the efficiency of CPPs, we monitored the modulation of GLT-1/PS1 interaction in intact neurons by FLIM. We saw significantly less interaction between PS1 and GLT-1 with both CPPs. Our study establishes a new tool to study the functional aspect of GLT-1/PS1 interaction and its relevance in normal physiology and AD models.

5.
Cancer Commun (Lond) ; 43(5): 525-561, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37005490

RESUMEN

Tumor development and metastasis are facilitated by the complex interactions between cancer cells and their microenvironment, which comprises stromal cells and extracellular matrix (ECM) components, among other factors. Stromal cells can adopt new phenotypes to promote tumor cell invasion. A deep understanding of the signaling pathways involved in cell-to-cell and cell-to-ECM interactions is needed to design effective intervention strategies that might interrupt these interactions. In this review, we describe the tumor microenvironment (TME) components and associated therapeutics. We discuss the clinical advances in the prevalent and newly discovered signaling pathways in the TME, the immune checkpoints and immunosuppressive chemokines, and currently used inhibitors targeting these pathways. These include both intrinsic and non-autonomous tumor cell signaling pathways in the TME: protein kinase C (PKC) signaling, Notch, and transforming growth factor (TGF-ß) signaling, Endoplasmic Reticulum (ER) stress response, lactate signaling, Metabolic reprogramming, cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) and Siglec signaling pathways. We also discuss the recent advances in Programmed Cell Death Protein 1 (PD-1), Cytotoxic T-Lymphocyte Associated Protein 4 (CTLA4), T-cell immunoglobulin mucin-3 (TIM-3) and Lymphocyte Activating Gene 3 (LAG3) immune checkpoint inhibitors along with the C-C chemokine receptor 4 (CCR4)- C-C class chemokines 22 (CCL22)/ and 17 (CCL17), C-C chemokine receptor type 2 (CCR2)- chemokine (C-C motif) ligand 2 (CCL2), C-C chemokine receptor type 5 (CCR5)- chemokine (C-C motif) ligand 3 (CCL3) chemokine signaling axis in the TME. In addition, this review provides a holistic understanding of the TME as we discuss the three-dimensional and microfluidic models of the TME, which are believed to recapitulate the original characteristics of the patient tumor and hence may be used as a platform to study new mechanisms and screen for various anti-cancer therapies. We further discuss the systemic influences of gut microbiota in TME reprogramming and treatment response. Overall, this review provides a comprehensive analysis of the diverse and most critical signaling pathways in the TME, highlighting the associated newest and critical preclinical and clinical studies along with their underlying biology. We highlight the importance of the most recent technologies of microfluidics and lab-on-chip models for TME research and also present an overview of extrinsic factors, such as the inhabitant human microbiome, which have the potential to modulate TME biology and drug responses.


Asunto(s)
Neoplasias , Microambiente Tumoral , Humanos , Neoplasias/metabolismo , Transducción de Señal , Procesos Neoplásicos , Receptores de Quimiocina/uso terapéutico , Quimiocinas/farmacología , Quimiocinas/uso terapéutico
6.
Sensors (Basel) ; 23(5)2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36904854

RESUMEN

Our unique multiplexed imaging assays employing FRET biosensors have previously detected that γ-secretase processes APP C99 primarily in late endosomes and lysosomes in live/intact neurons. Moreover we have shown that Aß peptides are enriched in the same subcellular loci. Given that γ-secretase is integrated into the membrane bilayer and functionally links to lipid membrane properties in vitro, it is presumable that γ-secretase function correlates with endosome and lysosome membrane properties in live/intact cells. In the present study, we show using unique live-cell imaging and biochemical assays that the endo-lysosomal membrane in primary neurons is more disordered and, as a result, more permeable than in CHO cells. Interestingly, γ-secretase processivity is decreased in primary neurons, resulting in the predominant production of long Aß42 instead of short Aß38. In contrast, CHO cells favor Aß38 over the Aß42 generation. Our findings are consistent with the previous in vitro studies, demonstrating the functional interaction between lipid membrane properties and γ-secretase and provide further evidence that γ-secretase acts in late endosomes and lysosomes in live/intact cells.


Asunto(s)
Enfermedad de Alzheimer , Secretasas de la Proteína Precursora del Amiloide , Cricetinae , Animales , Cricetulus , Péptidos beta-Amiloides/química , Endosomas , Lisosomas , Lípidos
7.
J Ayurveda Integr Med ; 13(4): 100636, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36436297

RESUMEN

BACKGROUND: Emerging reports indicate that age-associated cognitive decline begins with the transition from young to middle-aged, and this neurological condition manifests mainly due to the progressive impairment in the adaptive homeostasis process. Moreover, cognitive decline is associated with neurodegenerative changes in older adults. OBJECTIVE: Previous studies have shown that the administration of Ayurvedic formulations restores the homeostatic pathways and ameliorates neurodegeneration in animal models of neurodegenerative diseases. Therefore, we wanted to check whether Ayurvedic formulations can rescue or delay the age-associated cognitive decline in middle-aged mice. MATERIAL AND METHODS: We fed two-month-old mice with amalaki aasayana (AR, 1025 mg/kg per day) or rasa sindoor (RS, 41 mg/kg per day) mixed in a gelatin-based jelly for six months. Mice eating regular chow or blank jelly served as control. Subsequently, we looked at the improvements in the cognitive and behavioural traits of the treated animals. We have also analysed the effect of these formulations on the dendritic processes of neurons, glial activation, and the formation of corpora amylacea. RESULTS: We found a significant improvement in episodic, working- and reference-spatiotemporal memory in animals fed on AR or RS. Microscopic analyses revealed a significant increase in the dendritic spine density in the apical dendrites of the hippocampal pyramidal neurons. The treatment, however, did not significantly affect gliosis and corpora amylacea in the brains. CONCLUSIONS: Both AR and RS showed beneficial effects on memory functions of the middle-aged mice, possibly due to their effect on the dendritic spine densities. Our findings provide strong evidence to conclude that formulations AR and RS can prevent or delay the onset of age-associated cognitive decline.

8.
Perm J ; 26(2): 158-161, 2022 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-35933669

RESUMEN

Introduction Apocrine carcinoma, a cancer of sweat glands, is very rare, with a global incidence of 0.0049 to 0.0173 cases per 100,000 persons annually. It is usually found in axilla and anogenital areas. The intraductal apocrine variety of salivary duct carcinoma in the parotid gland is very rare and aggressive and may be due to ectopic sweat glands in the parotid gland duct or metaplastic change of the salivary duct epithelium. It usually presents in an advanced stage. Even though surgery is the standard of care in most head and neck cancers, there are no standard guidelines for the treatment of intraductal apocrine parotid carcinoma, which is different from other head and neck cancers due to its rare incidence, aggressive behavior, and poor prognosis. Case presentation We present a rare case of intraductal apocrine salivary duct carcinoma of the left parotid gland, presented in a locally advanced stage with very high chances of recurrence after surgery, and discuss the role of volumetric modulated arc technique radiotherapy in its management. Conclusion Intraductal apocrine salivary duct carcinoma usually has androgen receptor expression, and lack of expression is associated poor prognosis. Even with complete resection, it has a high recurrence rate. Volumetric modulated arc technique radiotherapy (VMAT) decreases recurrence and increases survival by irradiating the areas more likely of recurrence, with minimal toxicity to surrounding normal tissues.


Asunto(s)
Neoplasias de la Mama , Carcinoma Intraductal no Infiltrante , Neoplasias de Cabeza y Cuello , Neoplasias de las Glándulas Salivales , Femenino , Humanos , Glándula Parótida/patología , Glándula Parótida/cirugía , Neoplasias de las Glándulas Salivales/metabolismo , Neoplasias de las Glándulas Salivales/patología
9.
Int J Mol Sci ; 23(15)2022 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-35955767

RESUMEN

Hydrogen sulfide (H2S) and substance P (SP) are known from animal models and in vitro studies as proinflammatory mediators. In this study, peripheral blood concentrations of H2S and SP were measured in patients with Escherichia coli or Klebsiella pneumoniae bacteraemia. Fifty patients were recruited from general wards at Christchurch Hospital, during 2020-2021. Samples from age- and sex-matched healthy subjects previously recruited as controls for studies of cardiovascular disease were used as controls. The concentrations of H2S were higher than controls on day 0, day 1, and day 2, and SP was higher than controls on all 4 days. The concentrations of H2S were highest on day 0, whereas SP concentrations were higher on day 2 than other days. Interleukin-6 and C-reactive protein were significantly higher on day 0 and day 1, respectively. The concentrations of H2S and SP did not differ between 15 non-septic (SIRS 0-1) and the 35 septic subjects (SIRS ≥ 2). Substance P concentrations were higher in subjects with abdominal infection than urinary tract infections on day 0 (p = 0.0002) and day 1 (p = 0.0091). In conclusion, the peak H2S concentrations precede the SP peak in patients with Gram-negative bacteraemia, but this response varies with the site of infection.


Asunto(s)
Bacteriemia , Infecciones por Escherichia coli , Sulfuro de Hidrógeno , Animales , Escherichia coli/metabolismo , Humanos , Sulfuro de Hidrógeno/metabolismo , Klebsiella pneumoniae/metabolismo , Sustancia P
10.
Mol Neurobiol ; 59(9): 5532-5548, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35732865

RESUMEN

Brain aging is characterized by a gradual decline in cellular homeostatic processes, thereby losing the ability to respond to physiological stress. At the anatomical level, the aged brain is characterized by degenerating neurons, proteinaceous plaques and tangles, intracellular deposition of glycogen, and elevated neuroinflammation. Intriguingly, such age-associated changes are also seen in neurodegenerative disorders suggesting that an accelerated aging process could be one of the contributory factors for the disease phenotype. Amongst these, the genetic forms of progressive myoclonus epilepsy (PME), resulting from loss-of-function mutations in genes, manifest symptoms that are common to age-associated disorders, and genes mutated in PME are involved in the cellular homeostatic processes. Intriguingly, the incidence and/or onset of epileptic seizures are known to increase with age, suggesting that physiological changes in the aged brain might contribute to increased susceptibility to seizures. We, therefore, hypothesized that the expression level of genes implicated in PME might decrease with age, thereby leading to a compromised neuronal response towards physiological stress and hence neuroinflammation in the aging brain. Using mice models, we demonstrate here that the expression level of PME genes shows an inverse correlation with age, neuroinflammation, and compromised heat shock response. We further show that the pharmacological suppression of neuroinflammation ameliorates seizure susceptibility in aged animals as well as in animal models for a PME. Taken together, our results indicate a functional role for the PME genes in normal brain aging and that neuroinflammation could be a major contributory player in susceptibility to seizures.


Asunto(s)
Epilepsia , Epilepsias Mioclónicas Progresivas , Animales , Modelos Animales de Enfermedad , Ratones , Epilepsias Mioclónicas Progresivas/genética , Enfermedades Neuroinflamatorias , Convulsiones/genética
11.
Adv Exp Med Biol ; 1315: 129-159, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34302691

RESUMEN

Hydrogen sulfide (H2S) plays a vital role in human physiology and in the pathophysiology of several diseases. In addition, a substantial role of H2S in inflammation has emerged. This chapter will discuss the involvement of H2S in various inflammatory diseases. Furthermore, the contribution of reactive oxygen species (ROS), adhesion molecules, and leukocyte recruitment in H2S-mediated inflammation will be discussed. The interrelationship of H2S with other gasotransmitters in inflammation will also be examined. There is mixed literature on the contribution of H2S to inflammation due to studies reporting both pro- and anti-inflammatory actions. These apparent discrepancies in the literature could be resolved with further studies.


Asunto(s)
Gasotransmisores , Sulfuro de Hidrógeno , Humanos , Inflamación , Especies Reactivas de Oxígeno , Transducción de Señal
12.
Pharmacogenomics J ; 21(3): 359-375, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33649518

RESUMEN

Sodium valproate (VPA) is a histone deacetylase (HDAC) inhibitor, widely prescribed in the treatment of bipolar disorder, and yet the precise modes of therapeutic action for this drug are not fully understood. After exposure of the rat serotonergic cell line RN46A to VPA, RNA-sequencing (RNA-Seq) analysis showed widespread changes in gene expression. Analysis by four bioinformatic pipelines revealed as many as 230 genes were significantly upregulated and 72 genes were significantly downregulated. A subset of 23 differentially expressed genes was selected for validation using the nCounter® platform, and of these we obtained robust validation for ADAM23, LSP1, MAOB, MMP13, PAK3, SERPINB2, SNAP91, WNT6, and ZCCHC12. We investigated the effect of lithium on this subset and found four genes, CDKN1C, LSP1, SERPINB2, and WNT6 co-regulated by lithium and VPA. We also explored the effects of other HDAC inhibitors and the VPA analogue valpromide on the subset of 23 selected genes. Expression of eight of these genes, CDKN1C, MAOB, MMP13, NGFR, SHANK3, VGF, WNT6 and ZCCHC12, was modified by HDAC inhibition, whereas others did not appear to respond to several HDAC inhibitors tested. These results suggest VPA may regulate genes through both HDAC-dependent and independent mechanisms. Understanding the broader gene regulatory effects of VPA in this serotonergic cell model should provide insights into how this drug works and whether other HDAC inhibitor compounds may have similar gene regulatory effects, as well as highlighting molecular processes that may underlie regulation of mood.


Asunto(s)
Antimaníacos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/genética , Inhibidores de Histona Desacetilasas/farmacología , Serotonina/metabolismo , Transcripción Genética/genética , Ácido Valproico/farmacología , Animales , Línea Celular , Biología Computacional , Histona Desacetilasas/metabolismo , Litio/farmacología , RNA-Seq , Ratas , Activación Transcripcional
13.
Exp Neurol ; 340: 113656, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33639210

RESUMEN

Heat shock response (HSR) is a conserved cytoprotective pathway controlled by the master transcriptional regulator, the heat shock factor 1 (HSF1), that activates the expression of heat shock proteins (HSPs). HSPs, as chaperones, play essential roles in minimizing stress-induced damages and restoring proteostasis. Therefore, compromised HSR is thought to contribute to neurodegenerative disorders. Lafora disease (LD) is a fatal form of neurodegenerative disorder characterized by the accumulation of abnormal glycogen as Lafora bodies in neurons and other tissues. The symptoms of LD include progressive myoclonus epilepsy, dementia, and cognitive deficits. LD is caused by the defects in the gene coding laforin phosphatase or the malin ubiquitin ligase. Laforin and malin are known to work upstream of HSF1 and are essential for the activation of HSR. Herein, we show that mice deficient for laforin or malin show reduced levels of HSF1 and their targets in their brain tissues, suggesting compromised HSR; this could contribute to the neuropathology in LD. Intriguingly, treatment of LD animals with dexamethasone, a synthetic glucocorticoid analogue, partially restored the levels of HSF1 and its targets. Dexamethasone treatment was also able to ameliorate the neuroinflammation and susceptibility to induced seizures in the LD animals. However, dexamethasone treatment did not show a significant effect on Lafora bodies or autophagy defects. Taken together, the present study establishes a role for HSR in seizure susceptibility and neuroinflammation and dexamethasone as a potential antiepileptic agent, suitable for further studies in LD.


Asunto(s)
Antiinflamatorios/uso terapéutico , Dexametasona/uso terapéutico , Factores de Transcripción del Choque Térmico/metabolismo , Respuesta al Choque Térmico/efectos de los fármacos , Enfermedad de Lafora/metabolismo , Convulsiones/metabolismo , Animales , Antiinflamatorios/farmacología , Dexametasona/farmacología , Modelos Animales de Enfermedad , Factores de Transcripción del Choque Térmico/deficiencia , Factores de Transcripción del Choque Térmico/genética , Respuesta al Choque Térmico/fisiología , Inflamación/tratamiento farmacológico , Inflamación/genética , Inflamación/metabolismo , Enfermedad de Lafora/tratamiento farmacológico , Ratones , Ratones Noqueados , Convulsiones/tratamiento farmacológico
14.
Mol Neurobiol ; 58(3): 1088-1101, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33094475

RESUMEN

Lafora disease (LD) is one of the progressive and fatal forms of a neurodegenerative disorder and is characterized by teenage-onset myoclonic seizures. Neuropathological changes in LD include the formation of abnormal glycogen as Lafora bodies, gliosis, and neuroinflammation. LD is caused by defects in the gene coding for phosphatase (laforin) or ubiquitin ligase (malin). Mouse models of LD, developed by targeted disruption of these two genes, develop most symptoms of LD and show increased susceptibility to induced seizures. Studies on mouse models also suggest that defective autophagy might contribute to LD etiology. In an attempt to understand the specific role of autophagy in LD pathogenesis, in this study, we fed LD animals with trehalose, an inducer of autophagy, for 3 months and looked at its effect on the neuropathology and seizure susceptibility. We demonstrate here that trehalose ameliorates gliosis, neuroinflammation, and endoplasmic reticulum stress and reduces susceptibility to induced seizures in LD animals. However, trehalose did not affect the formation of Lafora bodies, suggesting the epileptic phenotype in LD could be either secondary to or independent of Lafora bodies. Taken together, our results suggest that autophagy inducers can be considered as potential therapeutic molecules for Lafora disease.


Asunto(s)
Encéfalo/patología , Estrés del Retículo Endoplásmico , Inflamación/patología , Enfermedad de Lafora/complicaciones , Convulsiones/tratamiento farmacológico , Convulsiones/etiología , Trehalosa/uso terapéutico , Animales , Autofagia/efectos de los fármacos , Autofagia/genética , Proteínas de Unión al Calcio/metabolismo , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Estrés del Retículo Endoplásmico/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Proteína Ácida Fibrilar de la Glía/metabolismo , Gliosis/complicaciones , Gliosis/patología , Glucanos/metabolismo , Inflamación/complicaciones , Enfermedad de Lafora/genética , Proteínas de la Membrana/metabolismo , Ratones Noqueados , Proteínas de Microfilamentos/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Pentilenotetrazol , Proteínas Tirosina Fosfatasas no Receptoras/deficiencia , Proteínas Tirosina Fosfatasas no Receptoras/metabolismo , Convulsiones/genética , Trehalosa/farmacología , Ubiquitina-Proteína Ligasas/deficiencia , Ubiquitina-Proteína Ligasas/metabolismo
15.
Front Mol Neurosci ; 13: 113, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32760249

RESUMEN

Cochlear implants (CIs) are widely used to provide auditory rehabilitation to individuals having severe to profound sensorineural hearing loss (SNHL). However, insertion of electrode leads to inner trauma and activation of inflammatory and apoptotic signaling cascades resulting in loss of residual hearing in implanted individuals. Pharmaceutical interventions that can target these signaling cascades hold great potential for preserving residual hearing by preventing sensory cell damage. Bile salts have shown efficacy in various regions of the body as powerful antioxidants and anti-inflammatory agents. However, their efficacy against inner ear trauma has never been explored. The objective of this study was to determine whether taurodeoxycholic acid (TDCA), a bile salt derivative, can prevent sensory cell damage employing an in vitro model of electrode insertion trauma (EIT). The organ of Corti (OC) explants were dissected from postnatal day 3 (P-3) rats and placed in serum-free media. Explants were divided into control and experimental groups: (1) untreated controls; (2) EIT; (3) EIT+ TDCA (different concentrations). Hair cell (HC) density, analyses of apoptosis pathway (cleaved caspase 3), levels of reactive oxygen species (ROS) as well as inducible nitric oxide synthase (iNOS) activity and Mitochondrial Membrane Potential (MMP) were assayed. Treatment with TDCA provided significant otoprotection against HC loss in a dose-dependent manner. The molecular mechanisms underlying otoprotection involved decreasing oxidative stress, lowering levels of iNOS, and abrogating generation of cleaved caspase 3. The results of the present study suggest that TDCA provides efficient otoprotection against EIT, in vitro and should be explored for developing pharmaceutical interventions to preserve residual hearing post-cochlear implantation.

16.
J Clin Med ; 9(3)2020 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-32155788

RESUMEN

BACKGROUND: Electrode insertion trauma (EIT) during cochlear implantation (CI) can cause loss of residual hearing. L-N-acetylcysteine (L-NAC) and dexamethasone (Dex) have been individually shown to provide otoprotection albeit at higher concentrations that may be associated with adverse effects. Objective/Aims: The aim of this study is to determine whether L-NAC and Dex could be combined to decrease their effective dosage. MATERIALS AND METHODS: The organ of Corti (OC) explants were divided into various groups: 1) control; 2) EIT; 3) EIT treated with different concentrations of Dex; 4) EIT treated with different concentrations of L-NAC; 5) EIT treated with L-NAC and Dex in combination. Hair cell (HC) density, levels of oxidative stress, proinflammatory cytokines and nitric oxide (NO) was determined. RESULTS: There was a significant loss of HCs in explants subjected to EIT compared to the control group. L-NAC and Dex in combination was able to provide significant otoprotection at lower concentrations compared to individual drugs. CONCLUSIONS AND SIGNIFICANCE: A combination containing L-NAC and Dex is effective in protecting sensory cells at lower protective doses than each compound separately. These compounds can be combined allowing a decrease of potential side effects of each compound and providing significant otoprotection for EIT.

18.
J Hum Reprod Sci ; 12(3): 224-228, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31576080

RESUMEN

BACKGROUND: Laparoscopic ovarian drilling (LOD) is one of the common modes of treatment for women with polycystic ovary syndrome (PCOS) who are resistant to clomiphene citrate. The data related to the effect of LOD on sex hormones are limited. AIM: The objective of the study was to investigate the effect of LOD on hormonal parameters and clinical outcomes in women with PCOS. SETTINGS AND DESIGN: This study was conducted in a tertiary care hospital. MATERIALS AND METHODS: Fifty PCOS patients who were admitted for LOD were enrolled in the study. Serum testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) levels were estimated in all the patients before and after LOD. STATISTICAL ANALYSIS: Paired t-test was used to assess the differences in hormonal parameters before and after LOD. RESULTS: LOD reduces testosterone (P < 0.001), LH (P < 0.001), and LH/FSH ratio (P < 0.001), increases FSH (P < 0.001) levels, and improves the rate of ovulation (38/50) and clinical pregnancy (21/50) in PCOS. When subgroup analysis was done, LOD significantly reduced testosterone and LH/FSH ratio in ovulatory and conceived groups. Furthermore, the menstrual cycle became regular, and hirsutism and acne were reduced after LOD in women with PCOS. CONCLUSIONS: LOD reduces testosterone and LH/FSH ratio and improves clinical outcome in PCOS.

19.
Int J Biol Macromol ; 117: 840-850, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29807085

RESUMEN

The present study aims to investigate the efficacy of the novel biopolymeric complex multiparticulate system consisting of chitosan succinate and alginate for the capecitabine-targeted delivery to colon cancer. A Box-Behnken design was used to optimize the CS-SA beads by considering the effect of three factors: CS (A;X1), CaCl2 (B;X2), and SA (C;X3), on the response variables Y1 (EE), Y2 (Size), and Y3 (Release). The results of response surface plots allowed an optimized bead to be identified with high drug EE and maximum drug release at colon. The swelling index showed that the beads reached a maximum good swelling at pH 7.4, and nil or little swelling at acidic pH, which proves that the beads completely protect the release of drug. The in vitro release portrayed a maximum release at pH 7.4, due to the large swelling force that was created by electrostatic repulsion between the ionized carboxylic acid groups of the CS-SA network. In vitro cytotoxicity assay (MTT) of CS-SA beads shows inhibition of the proliferation of HT-29 tumour cell to induce apoptosis over a longer period of time. The above results show that CS-SA beads prolong the release of CP in the colonic region, and also enhance antitumor efficacy.


Asunto(s)
Alginatos/química , Capecitabina/química , Capecitabina/farmacología , Quitosano/química , Neoplasias del Colon/tratamiento farmacológico , Portadores de Fármacos/química , Animales , Capecitabina/metabolismo , Capecitabina/uso terapéutico , Cápsulas , Ciego/metabolismo , Supervivencia Celular/efectos de los fármacos , Liberación de Fármacos , Ácido Glucurónico/química , Células HT29 , Ácidos Hexurónicos/química , Humanos , Concentración de Iones de Hidrógeno , Cinética , Ratas , Temperatura
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