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1.
Methods Mol Biol ; 2761: 1-26, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38427225

RESUMO

Detection of merely apoptosis does not reveal the type of central nervous system (CNS) cells that are dying in the CNS diseases and injuries. In situ detection and estimation of amount of apoptosis specifically in neurons or glial cells (astrocytes, oligodendrocytes, and microglia) can unveil valuable information for designing therapeutics for protection of the CNS cells and functional recovery. A method was first developed and reported from our laboratory for in situ detection and estimation of amount of apoptosis precisely in neurons and glial cells using in vitro and in vivo models of CNS diseases and injuries. This is a combination of terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and double immunofluorescent labeling (DIFL) or simply TUNEL-n-DIFL method for in situ detection and estimation of amount of apoptosis in a specific CNS cell type. An anti-digoxigenin (DIG) IgG antibody conjugated with 7-amino-4-methylcoumarin-3-acetic acid (AMCA) for blue fluorescence, fluorescein isothiocyanate (FITC) for green fluorescence, or Texas Red (TR) for red fluorescence can be used for in situ detection of apoptotic cell DNA, which is earlier labeled with TUNEL using alkali-stable DIG-11-dUTP. A primary anti-NeuN (neurons), anti-GFAP (astrocytes), anti-MBP (oligodendrocytes), or anti-OX-42 (microglia) IgG antibody and a secondary IgG antibody conjugated with one of the above fluorophores (other than that of ani-DIG antibody) are used for in situ detection of apoptosis in a specific CNS cell type in the mixed culture and animal models of the CNS diseases and injuries.


Assuntos
Apoptose , Doenças do Sistema Nervoso Central , Animais , Marcação In Situ das Extremidades Cortadas , Apoptose/genética , Neuroglia , Neurônios/metabolismo , Doenças do Sistema Nervoso Central/metabolismo , Modelos Animais de Doenças , Imunoglobulina G/metabolismo
2.
Methods Mol Biol ; 2761: 149-157, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38427236

RESUMO

Chromatographic separation and purification of an individual lipid to homogeneity have long been introduced. Using this concept, a more precise method has been developed to identify and characterize the sphingolipid composition(s) using a small amount (30 mg) of biological sample. Sphingolipids (lipids containing sphingosine or dihydrosphingosine) are well-known regulators of the central nervous system development and play a critical role in neurodegenerative diseases. Introducing a silicic acid column chromatography, sphingolipid components have been separated to individual fractions such as ceramide, glucosyl/galactosylceramide, other neutral and acidic glycosphingolipids, including (dihydro)sphingosine and psychosine; as well as phospholipids from which individual components are quantified employing a single or combination of other advanced chromatography procedures such as thin-layer chromatography, gas chromatography-mass spectrometry, and high-performance liquid chromatography-mass spectrometry.


Assuntos
Esfingolipídeos , Esfingosina , Esfingolipídeos/química , Esfingosina/análise , Ceramidas/análise , Cromatografia em Camada Delgada/métodos , Sistema Nervoso Central/química
3.
Brain Sci ; 14(1)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38275516

RESUMO

There are approximately 24 million cases of Alzheimer's disease (AD) worldwide, and the number of cases is expected to increase four-fold by 2050. AD is a neurodegenerative disease that leads to severe dementia in most patients. There are several neuropathological signs of AD, such as deposition of amyloid beta (Aß) plaques, formation of neurofibrillary tangles (NFTs), neuronal loss, activation of inflammasomes, and declining autophagy. Several of these hallmarks are linked to the gut microbiome. The gastrointestinal (GI) tract contains microbial diversity, which is important in regulating several functions in the brain via the gut-brain axis (GBA). The disruption of the balance in the gut microbiota is known as gut dysbiosis. Recent studies strongly support that targeting gut dysbiosis with selective bioflavonoids is a highly plausible solution to attenuate activation of inflammasomes (contributing to neuroinflammation) and resume autophagy (a cellular mechanism for lysosomal degradation of the damaged components and recycling of building blocks) to stop AD pathogenesis. This review is focused on two bioflavonoids, specifically epigallocatechin-3-gallate (EGCG) and genistein (GS), as a possible new paradigm of treatment for maintaining healthy gut microbiota in AD due to their implications in modulating crucial AD signaling pathways. The combination of EGCG and GS has a higher potential than either agent alone to attenuate the signaling pathways implicated in AD pathogenesis. The effects of EGCG and GS on altering gut microbiota and GBA were also explored, along with conclusions from various delivery methods to increase the bioavailability of these bioflavonoids in the body.

4.
Cells ; 12(6)2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36980238

RESUMO

As the most malignant primary brain tumor in adults, a diagnosis of glioblastoma multiforme (GBM) continues to carry a poor prognosis. GBM is characterized by cytoprotective homeostatic processes such as the activation of autophagy, capability to confer therapeutic resistance, evasion of apoptosis, and survival strategy even in the hypoxic and nutrient-deprived tumor microenvironment. The current gold standard of therapy, which involves radiotherapy and concomitant and adjuvant chemotherapy with temozolomide (TMZ), has been a game-changer for patients with GBM, relatively improving both overall survival (OS) and progression-free survival (PFS); however, TMZ is now well-known to upregulate undesirable cytoprotective autophagy, limiting its therapeutic efficacy for induction of apoptosis in GBM cells. The identification of targets utilizing bioinformatics-driven approaches, advancement of modern molecular biology technologies such as clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein (Cas9) or CRISPR-Cas9 genome editing, and usage of microRNA (miRNA)-mediated regulation of gene expression led to the selection of many novel targets for new therapeutic development and the creation of promising combination therapies. This review explores the current state of advanced bioinformatics analysis and genetic technologies and their utilization for synergistic combination with TMZ in the context of inhibition of autophagy for controlling the growth of GBM.


Assuntos
Neoplasias Encefálicas , Glioblastoma , MicroRNAs , Adulto , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Temozolomida/farmacologia , Temozolomida/uso terapêutico , MicroRNAs/genética , MicroRNAs/uso terapêutico , Autofagia/genética , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Microambiente Tumoral
5.
Neural Regen Res ; 18(3): 492-496, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36018152

RESUMO

Spinal cord injury is one of the leading causes of morbidity and mortality among young adults in many countries including the United States. Difficulty in the regeneration of neurons is one of the main obstacles that leave spinal cord injury patients with permanent paralysis in most instances. Recent research has found that preventing acute and subacute secondary cellular damages to the neurons and supporting glial cells can help slow the progression of spinal cord injury pathogenesis, in part by reactivating endogenous regenerative proteins including Noggin that are normally present during spinal cord development. Noggin is a complex protein and natural inhibitor of the multifunctional bone morphogenetic proteins, and its expression is high during spinal cord development and after induction of spinal cord injury. In this review article, we first discuss the change in expression of Noggin during pathogenesis in spinal cord injury. Second, we discuss the current research knowledge about the neuroprotective role of Noggin in preclinical models of spinal cord injury. Lastly, we explain the gap in the knowledge for the use of Noggin in the treatment of spinal cord injury. The results from extensive in vitro and in vivo research have revealed that the therapeutic efficacy of Noggin treatment remains debatable due to its neuroprotective effects observed only in early phases of spinal cord injury but little to no effect on altering pathogenesis and functional recovery observed in the chronic phase of spinal cord injury. Furthermore, clinical information regarding the role of Noggin in the alleviation of progression of pathogenesis, its therapeutic efficacy, bioavailability, and safety in human spinal cord injury is still lacking and therefore needs further investigation.

6.
Cells ; 11(24)2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36552827

RESUMO

Glioblastoma multiforme (GBM) is a brain tumor notorious for its propensity to recur after the standard treatments of surgical resection, ionizing radiation (IR), and temozolomide (TMZ). Combined with the acquired resistance to standard treatments and recurrence, GBM is an especially deadly malignancy with hardly any worthwhile treatment options. The treatment resistance of GBM is influenced, in large part, by the contributions from two main degradative pathways in eukaryotic cells: ubiquitin-proteasome system (UPS) and autophagy. These two systems influence GBM cell survival by removing and recycling cellular components that have been damaged by treatments, as well as by modulating metabolism and selective degradation of components of cell survival or cell death pathways. There has recently been a large amount of interest in potential cancer therapies involving modulation of UPS or autophagy pathways. There is significant crosstalk between the two systems that pose therapeutic challenges, including utilization of ubiquitin signaling, the degradation of components of one system by the other, and compensatory activation of autophagy in the case of proteasome inhibition for GBM cell survival and proliferation. There are several important regulatory nodes which have functions affecting both systems. There are various molecular components at the intersections of UPS and autophagy pathways that pose challenges but also show some new therapeutic opportunities for GBM. This review article aims to provide an overview of the recent advancements in research regarding the intersections of UPS and autophagy with relevance to finding novel GBM treatment opportunities, especially for combating GBM treatment resistance.


Assuntos
Glioblastoma , Humanos , Glioblastoma/metabolismo , Ubiquitina/metabolismo , Complexo de Endopeptidases do Proteassoma , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Autofagia
7.
Brain Sci ; 12(2)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35204010

RESUMO

The treatment of spinal cord injury (SCI) is currently a major challenge, with a severe lack of effective therapies for yielding meaningful improvements in function. Therefore, there is a great opportunity for the development of novel treatment strategies for SCI. The modulation of autophagy, a process by which a cell degrades and recycles unnecessary or harmful components (protein aggregates, organelles, etc.) to maintain cellular homeostasis and respond to a changing microenvironment, is thought to have potential for treating many neurodegenerative conditions, including SCI. The discovery of microRNAs (miRNAs), which are short ribonucleotide transcripts for targeting of specific messenger RNAs (mRNAs) for silencing, shows prevention of the translation of mRNAs to the corresponding proteins affecting various cellular processes, including autophagy. The number of known miRNAs and their targets continues to grow rapidly. This review article aims to explore the relationship between autophagy and SCI, specifically with the intent of identifying specific miRNAs that can be useful to modulate autophagy for neuroprotection and the improvement of functional recovery in SCI.

8.
Int J Mol Sci ; 23(4)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35216504

RESUMO

Spinal cord injury (SCI) causes significant mortality and morbidity. Currently, no FDA-approved pharmacotherapy is available for treating SCI. Previously, low doses of estrogen (17ß-estradiol, E2) were shown to improve the post-injury outcome in a rat SCI model. However, the range of associated side effects makes advocating its therapeutic use difficult. Therefore, this study aimed at investigating the therapeutic efficacy of Premarin (PRM) in SCI. PRM is an FDA-approved E2 (10%) formulation, which is used for hormone replacement therapy with minimal risk of serious side effects. The effects of PRM on SCI were examined by magnetic resonance imaging, immunofluorescent staining, and western blot analysis in a rat model. SCI animals treated with vehicle alone, PRM, E2 receptor antagonist (ICI), or PRM + ICI were graded in a blinded way for locomotor function by using the Basso-Beattie-Bresnahan (BBB) locomotor scale. PRM treatment for 7 days decreased post-SCI lesion volume and attenuated neuronal cell death, inflammation, and axonal damage. PRM also altered the balance of pro- and anti-apoptotic proteins in favor of cell survival and improved angiogenesis and microvascular growth. Increased expression of estrogen receptors (ERs) ERα and ERß following PRM treatment and their inhibition by ER inhibitor indicated that the neuroprotection associated with PRM treatment might be E2-receptor mediated. The attenuation of glial activation with decreased inflammation and cell death, and increased angiogenesis by PRM led to improved functional outcome as determined by the BBB locomotor scale. These results suggest that PRM treatment has significant therapeutic implications for the improvement of post-SCI outcome.


Assuntos
Estrogênios Conjugados (USP)/farmacologia , Doenças Neurodegenerativas/tratamento farmacológico , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Axônios/efeitos dos fármacos , Axônios/metabolismo , Modelos Animais de Doenças , Estradiol/metabolismo , Estrogênios/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Locomoção/efeitos dos fármacos , Masculino , Atividade Motora/efeitos dos fármacos , Doenças Neurodegenerativas/metabolismo , Neuroproteção/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/metabolismo
9.
Apoptosis ; 26(11-12): 574-599, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34687375

RESUMO

Around three out of one hundred thousand people are diagnosed with glioblastoma multiforme, simply called glioblastoma, which is the most common primary brain tumor in adults. With a dismal prognosis of a little over a year, receiving a glioblastoma diagnosis is oftentimes fatal. A major advancement in its treatment was made almost two decades ago when the alkylating chemotherapeutic agent temozolomide (TMZ) was combined with radiotherapy (RT). Little progress has been made since then. Therapies that focus on the modulation of autophagy, a key process that regulates cellular homeostasis, have been developed to curb the progression of glioblastoma. The dual role of autophagy (cell survival or cell death) in glioblastoma has led to the development of autophagy inhibitors and promoters that either work as monotherapies or as part of a combination therapy to induce cell death, cellular senescence, and counteract the ability of glioblastoma stem cells (GSCs) for initiating tumor recurrence. The myriad of cellular pathways that act upon the modulation of autophagy have created contention between two groups: those who use autophagy inhibition versus those who use promotion of autophagy to control glioblastoma growth. We discuss rationale for using current major therapeutics, their molecular mechanisms for modulation of autophagy in glioblastoma and GSCs, their potentials for making strides in combating glioblastoma progression, and their possible shortcomings. These shortcomings may fuel the innovation of novel delivery systems and therapies involving TMZ in conjunction with another agent to pave the way towards a new gold standard of glioblastoma treatment.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Antineoplásicos Alquilantes/uso terapêutico , Apoptose , Autofagia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Humanos , Recidiva Local de Neoplasia
10.
Cells ; 10(9)2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34571991

RESUMO

Glioblastoma multiforme (GBM) is an aggressive malignancy of the brain and spinal cord with a poor life expectancy. The low survivability of GBM patients can be attributed, in part, to its heterogeneity and the presence of multiple genetic alterations causing rapid tumor growth and resistance to conventional therapy. The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-CRISPR associated (Cas) nuclease 9 (CRISPR-Cas9) system is a cost-effective and reliable gene editing technology, which is widely used in cancer research. It leads to novel discoveries of various oncogenes that regulate autophagy, angiogenesis, and invasion and play important role in pathogenesis of various malignancies, including GBM. In this review article, we first describe the principle and methods of delivery of CRISPR-Cas9 genome editing. Second, we summarize the current knowledge and major applications of CRISPR-Cas9 to identifying and modifying the genetic regulators of the hallmark of GBM. Lastly, we elucidate the major limitations of current CRISPR-Cas9 technology in the GBM field and the future perspectives. CRISPR-Cas9 genome editing aids in identifying novel coding and non-coding transcriptional regulators of the hallmarks of GBM particularly in vitro, while work using in vivo systems requires further investigation.


Assuntos
Edição de Genes/métodos , Glioblastoma/genética , Glioblastoma/terapia , Proteína 9 Associada à CRISPR/genética , Sistemas CRISPR-Cas/genética , Endonucleases/genética , Expressão Gênica/genética , Regulação da Expressão Gênica/genética , Técnicas de Transferência de Genes/tendências , Terapia Genética/métodos , Glioblastoma/metabolismo , Humanos , Mutação/genética , Oncogenes/genética
11.
Neuroimmunol Neuroinflamm ; 8: 53-63, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33869676

RESUMO

Spinal cord injury (SCI) is a debilitating injury that results from traumatic or non-traumatic insults to the spinal cord, causing significant impairment of the patient's activity and quality of life. Bone morphogenic proteins (BMPs) are a group of polyfunctional cytokines belonging to the transforming growth factor beta superfamily that regulates a wide variety of cellular functions in healthy and disease states. Recent studies suggest that dysregulation of BMP signaling is involved in neuronal demyelination and death after traumatic SCI. The focus of this article is to describe our current understanding of the role of BMP signaling in the regulation of cell fate, proliferation, apoptosis, autophagy, and inflammation in traumatic SCI. First, we will describe the expression of BMPs and pattern of BMP signaling before and after traumatic SCI in rodent models and in vitro. Next, we will discuss the role of BMP in the regulation of neuronal and glial cell differentiation, survival, functional recovery from traumatic SCI, and the gap in knowledge in this area that requires further investigation to improve SCI prognosis.

12.
Neurotox Res ; 38(3): 640-649, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32761446

RESUMO

Extra-nigral central nervous system sites have been found to be affected in Parkinson's disease (PD). In addition to substantia nigra, degeneration of spinal cord motor neurons may play a role in the motor symptoms of PD. To this end, hybrid rodent VSC 4.1 cells differentiated into motoneurons were used as a cell culture model following exposure to Parkinsonian neurotoxicant MPP+. SJA6017, a cell-permeable calpain inhibitor, was tested for its neuroprotective efficacy against the neurotoxicant. SJA6017 attenuated MPP+-induced rise in intracellular free Ca2+ and concomitant increases in the active form of calpain. It also significantly prevented increased levels of proteases and their activities, as shown by reduced levels of 145 kDa calpain-specific and 120 kDa caspase-3-specific spectrin breakdown products. Exposure to MPP+ elevated the levels of reactive oxygen species in VSC 4.1 motoneurons; this was significantly diminished with SJA6017. The motor proteins in spinal motoneurons, i.e., dynein and kinesin, were also impaired following exposure to MPP+ through calpain-mediated mechanisms; this process was partially ameliorated by SJA6017 pretreatment. Cytoprotection provided by SJA6017 against MPP+-induced damage to VSC 4.1 motoneurons was confirmed by restoration of membrane potential via whole-cell patch-clamp assay. This study demonstrates that calpain inhibition is a prospective route for neuroprotection in experimental PD; moreover, calpain inhibitor SJA6017 appears to be an effective neuroprotective agent against MPP+-induced damage in spinal motoneurons.


Assuntos
Calpaína/farmacologia , Dipeptídeos/farmacologia , Glicoproteínas/farmacologia , Neurônios Motores/metabolismo , Animais , Apoptose/efeitos dos fármacos , Calpaína/metabolismo , Neurônios Motores/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Medula Espinal/citologia , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo
13.
Neurochem Res ; 45(10): 2336-2351, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32683533

RESUMO

Fenugreek (Trigonella foenum-graecum) seeds and roots of wild yam (Dioscorea villosa) possess nutritional and medicinal properties and have been used for centuries in traditional medicine to treat different diseases and inflammatory responses. Diosgenin is a natural steroidal sapogenin extracted from fenugreek and wild yam and it is one of the major bioactive compounds used in the treatment of diabetes, hypercholesterolemia, and inflammation. Recent studies have shown a promising effect of diosgenin as an anti-tumor agent for inhibition of cell proliferation and induction of apoptosis in many cancers such as colon cancer, leukemia, breast cancer, and liver cancer. We examined the effects of different concentrations (5, 10, 15, 20, and 25 µM) of diosgenin on proliferation of rat C6 and human T98G glioblastoma cell lines. We noticed that diosgenin had a high inhibitory effect on the growth of both C6 and T98G cell lines. Diosgenin induced the differentiation of glioblastoma cells, as determined by the increase in the expression of the differentiation marker glial fibrillary acidic protein (GFAP); and decreased the dedifferentiation of the cells, as shown by the decrease in the abundance of the dedifferentiation marker proteins Id2, N-Myc, telomerase reverse transcriptase (TERT), and Notch-1. It also induced apoptosis in C6 and T98G cell lines and the molecular mechanisms involved in the induction of apoptosis included increase in pro-apoptotic Bax protein and decrease in anti-apoptotic Bcl-2 protein. Further, the diosgenin-induced suppression of cell migration was correlated with the decrease in expression of matrix metalloproteinase 2 (MMP2) and MMP9; and the inhibition of angiogenesis, as determined by the tube formation assay, was correlated with a decrease in the protein levels of vascular endothelial growth factor (VEGF) and fibroblast growth factor 2 (FGF2). In conclusion, diosgenin showed anti-tumor effects in glioblastoma cells by induction of differentiation and apoptosis and inhibition of migration, invasion, and angiogenesis.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Diosgenina/farmacologia , Glioblastoma/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Proteína X Associada a bcl-2/metabolismo
14.
Neural Regen Res ; 15(9): 1601-1612, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32209759

RESUMO

Spinal cord injury (SCI) is a serious central nervous system trauma that leads to loss of motor and sensory functions in the SCI patients. One of the cell death mechanisms is autophagy, which is 'self-eating' of the damaged and misfolded proteins and nucleic acids, damaged mitochondria, and other impaired organelles for recycling of cellular building blocks. Autophagy is different from all other cell death mechanisms in one important aspect that it gives the cells an opportunity to survive or demise depending on the circumstances. Autophagy is a therapeutic target for alleviation of pathogenesis in traumatic SCI. However, functions of autophagy in traumatic SCI remain controversial. Spatial and temporal patterns of activation of autophagy after traumatic SCI have been reported to be contradictory. Formation of autophagosomes following therapeutic activation or inhibition of autophagy flux is ambiguous in traumatic SCI studies. Both beneficial and harmful outcomes due to enhancement autophagy have been reported in traumatic SCI studies in preclinical models. Only further studies will make it clear whether therapeutic activation or inhibition of autophagy is beneficial in overall outcomes in preclinical models of traumatic SCI. Therapeutic enhancement of autophagy flux may digest the damaged components of the central nervous system cells for recycling and thereby facilitating functional recovery. Many studies demonstrated activation of autophagy flux and inhibition of apoptosis for neuroprotective effects in traumatic SCI. Therapeutic induction of autophagy in traumatic SCI promotes axonal regeneration, supporting another beneficial role of autophagy in traumatic SCI. In contrast, some other studies demonstrated that disruption of autophagy flux in traumatic SCI strongly correlated with neuronal death at remote location and impaired functional recovery. This article describes our current understanding of roles of autophagy in acute and chronic traumatic SCI, cross-talk between autophagy and apoptosis, therapeutic activation or inhibition of autophagy for promoting functional recovery, and future of autophagy in traumatic SCI.

15.
Apoptosis ; 25(3-4): 217-232, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32006189

RESUMO

Glioblastoma is the most malignant and prevalent brain tumor in adults. It can grow and spread quickly causing harm to the brain health. One of the major challenges in treatment of glioblastoma is drug resistance. Use of synergistic combination of two drugs with different anti-tumor effects is nowadays highly considered in the development of effective therapeutic strategies for many malignancies. In the present study, we showed synergistic therapeutic efficacies of two chemical compounds, N-(4-hydroxyphenyl) retinamide (4HPR) and suberoylanilide hydroxamic acid (SAHA), for significant reduction in cell viability of rat C6 and human T98G glioblastoma cells. These compounds (4HPR and SAHA) were used alone or in synergistic combination for evaluating their various anti-tumor effects. The results showed that combination of 4HPR and SAHA significantly induced morphological and molecular features of astrocytic differentiation in C6 and T98G glioblastoma cells. Combination of 4HPR and SAHA proved to be an important therapeutic strategy for inhibiting cell growth and inducing differentiation in glioblastoma cells. Furthermore, combination of the two drugs showed more efficacies than either dug alone in reducing in vitro cell invasion (transwell assay), cell migration (wound healing assay), and angiogenesis (tube formation assay) due to down regulation of the molecules involved in these processes. The ultimate of goal of using this combination of drugs was induction of apoptosis. The results showed that these drugs in synergistic combination contributed highly to increases in morphological and molecular features of apoptotic death in the tumor cells. The results from molecular studies indicated that cell death occurred via activation of the extrinsic and intrinsic pathways of apoptosis in both C6 and T98G cells. The drugs in combination also contributed to dramatic inhibition of histone deacetylase 1, an important epigenetic player in promoting growth in glioblastoma cells. This novel combination of drugs should also be considered as a promising therapeutic strategy for the treatment of glioblastoma in vivo.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Fenretinida/farmacologia , Glioblastoma/patologia , Vorinostat/farmacologia , Proteínas Angiogênicas/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Glioblastoma/tratamento farmacológico , Histona Desacetilase 1/antagonistas & inibidores , Humanos , Ratos
16.
Int J Mol Sci ; 20(20)2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31614447

RESUMO

Ceramide and sphingosine display a unique profile during brain development, indicating their critical role in myelinogenesis. Employing advanced technology such as gas chromatography-mass spectrometry, high performance liquid chromatography, and immunocytochemistry, along with cell culture and molecular biology, we have found an accumulation of sphingosine in brain tissues of patients with multiple sclerosis (MS) and in the spinal cord of rats induced with experimental autoimmune encephalomyelitis. The elevated sphingosine leads to oligodendrocyte death and fosters demyelination. Ceramide elevation by serine palmitoyltransferse (SPT) activation was the primary source of the sphingosine elevation as myriocin, an inhibitor of SPT, prevented sphingosine elevation and protected oligodendrocytes. Supporting this view, fingolimod, a drug used for MS therapy, reduced ceramide generation, thus offering partial protection to oligodendrocytes. Sphingolipid synthesis and degradation in normal development is regulated by a series of microRNAs (miRNAs), and hence, accumulation of sphingosine in MS may be prevented by employing miRNA technology. This review will discuss the current knowledge of ceramide and sphingosine metabolism (synthesis and breakdown), and how their biosynthesis can be regulated by miRNA, which can be used as a therapeutic approach for MS.


Assuntos
Ceramidas/biossíntese , MicroRNAs/genética , Esclerose Múltipla/genética , Serina C-Palmitoiltransferase/metabolismo , Esfingosina/biossíntese , Animais , Encéfalo/metabolismo , Cloridrato de Fingolimode/farmacologia , Cloridrato de Fingolimode/uso terapêutico , Humanos , MicroRNAs/antagonistas & inibidores , Terapia de Alvo Molecular , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/metabolismo , Bainha de Mielina/metabolismo , Ratos , Serina C-Palmitoiltransferase/antagonistas & inibidores
17.
Neural Regen Res ; 14(11): 1880-1892, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31290437

RESUMO

All retinoids, which can be natural and synthetic, are chemically related to vitamin A. Both natural and synthetic retinoids use specific nuclear receptors such as retinoic acid receptors and retinoid X receptors to activate specific signaling pathways in the cells. Retinoic acid signaling is extremely important in the central nervous system. Impairment of retinoic acid signaling pathways causes severe pathological processes in the central nervous system, especially in the adult brain. Retinoids have major roles in neural patterning, differentiation, axon outgrowth in normal development, and function of the brain. Impaired retinoic acid signaling results in neuroinflammation, oxidative stress, mitochondrial malfunction, and neurodegeneration leading to progressive Alzheimer's disease, which is pathologically characterized by extra-neuronal accumulation of amyloid plaques (aggregated amyloid-beta) and intra-neurofibrillary tangles (hyperphosphorylated tau protein) in the temporal lobe of the brain. Alzheimer's disease is the most common cause of dementia and loss of memory in old adults. Inactive cholinergic neurotransmission is responsible for cognitive deficits in Alzheimer's disease patients. Deficiency or deprivation of retinoic acid in mice is associated with loss of spatial learning and memory. Retinoids inhibit expression of chemokines and neuroinflammatory cytokines in microglia and astrocytes, which are activated in Alzheimer's disease. Stimulation of retinoic acid receptors and retinoid X receptors slows down accumulation of amyloids, reduces neurodegeneration, and thereby prevents pathogenesis of Alzheimer's disease in mice. In this review, we described chemistry and biochemistry of some natural and synthetic retinoids and potentials of retinoids for prevention of neuroinflammation and neurodegeneration in Alzheimer's disease.

18.
Methods Mol Biol ; 2019: 257-273, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31359402

RESUMO

Detection of any decrease in telomerase activity in cancer cells and tumor tissues is an important part in assessing overall therapeutic outcomes of a treatment agent in the laboratory and clinical settings. Almost 85% of cancers have activation of telomerase activity that promotes cell proliferation and discourages differentiation to sustain growth of the cancers. Retinoids are highly regarded as the anti-proliferation and pro-differentiation agents that cause down regulation of telomerase activity in the cancer cells. Two (nonradioactive and radioactive) telomeric repeat amplification protocol (TRAP) assays are optimized and fully described for detection of the diminished or abolished telomerase activity in a very low amount of protein extracts from cancer cells after treatment with a natural retinoid or a synthetic retinoid. These highly optimized and improved nonradioactive and radioactive TRAP assays can also be used for determining the presence or absence of telomerase activity in a small amount of any tumor tissue. The results from these TRAP assays can also help decide appropriate therapeutic options for the cancers with or without telomerase activity.


Assuntos
Neoplasias/enzimologia , Técnicas de Amplificação de Ácido Nucleico/métodos , Retinoides/farmacologia , Telomerase/metabolismo , Telômero/genética , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Células HL-60 , Humanos , Neoplasias/tratamento farmacológico , Radioatividade , Sequências Repetitivas de Ácido Nucleico , Tamanho da Amostra , Telomerase/efeitos dos fármacos
19.
Neurochem Res ; 44(7): 1715-1725, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31011879

RESUMO

This study investigated the efficacy of quercetin (QCT) in combination with sodium butyrate (NaB) in enhancing apoptosis in rat C6 and human T98G glioblastoma cells though blockage of autophagy under nutrient-starvation. The most synergistic doses of the drugs were determined to be 25 µM QCT and 1 mM NaB in both cell lines. After QCT and QCT + NaB treatments, autophagy quantification with acridine orange staining showed a drastic decrease in protective autophagy in the cells under nutrient-starvation. Decrease in autophagy was correlated with decreases in expression of Beclin-1 and LC3B II. Combination treatment increased the morphological signs of apoptosis including membrane blebbing, nuclear fragmentation, and chromatin condensation. Annexin V staining was also performed for detection and quantification of increases in apoptosis. Western blotting results showed that combination of QCT and NaB increased apoptosis by decreasing anti-apoptotic Bcl-2 and increasing pro-apoptotic Bax, decreasing survivin, activating caspase-3, and degrading poly (ADP-ribose) polymerase (PARP). This study demonstrated the therapeutic potentials of a novel combination therapy in inhibiting protective autophagy to enhance apoptosis in rat C6 and human T98G glioblastoma cells.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Ácido Butírico/farmacologia , Quercetina/farmacologia , Animais , Proteína Beclina-1/metabolismo , Caspase 3/metabolismo , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Glioblastoma/patologia , Inibidores de Histona Desacetilases/farmacologia , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Proteína X Associada a bcl-2/metabolismo
20.
Artigo em Inglês | MEDLINE | ID: mdl-33869674

RESUMO

Individuals having sustained traumatic spinal cord injury (TSCI) in the United States are living longer as compared to historical trends, thanks to an ever-evolving understanding of the nature of this injury. Despite this, multiple barriers to care for TSCI patients remain including variations in government-issued veteran insurance, privatized insurance, and among uninsured individuals. The United States alone experiences 12,000 new TSCI cases every year, many of these are found to occur in a growing proportion of elderly individuals. It is crucial to understand both the short-term direct costs as wells as the long-term rehabilitation costs required by these TSCI patients. The lifetime financial burden for those having sustained a TSCI can be immense for patients, insurance companies, and hospital systems alike. Among those with TSCI, re-hospitalization rates are high, leading to increased healthcare resource utilization within this specific patient population. Costs can quickly balloon into hundreds of thousands of dollars and cause a profound financial burden for these patients. This review article seeks to communicate an understanding of the current financial landscape surrounding TSCI patients. The authors will also examine the costs of acute emergency room surgical care such as American spinal injury association grade, hospital length of stay, as well as the timing delay between injury and surgical decompression. Long-term costs associated with TSCI such as rehabilitation, care of secondary comorbidities, and post-injury employment prospects will be examined as well. These costs will be framed from the patient's perspective as well as from both the hospital and insurance company's perspectives. It is hoped a complete understanding as to what makes TSCI such a medically and financially burdensome injury will allow for improved healthcare resource utilization in this population.

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