RESUMO
Neuropathic pain (NP) is characterized by hyperalgesia, allodynia, and spontaneous pain. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channel involved in neuronal hyperexcitability, has emerged as an important target for the drug development of NP. HCN channels exist in four different isoforms, where HCN1 is majorly expressed in dorsal root ganglion having an imperative role in NP pathophysiology. A specific HCN1 channel inhibitor will hold the better potential to treat NP without disturbing the physiological roles of other HCN isoforms. The main objective is to identify and analyze the chemical properties of scaffolds with higher HCN1 channel specificity. The 3D-QSAR studies highlight the hydrophobic & hydrogen bond donor groups enhance specificity towards the HCN1 channel. Further, the molecular interaction of the scaffolds with the HCN1 pore was studied by generating an open-pore model of the HCN1 channel using homology modelling and then docking the molecules with it. In addition, the important residues involved in the interaction between HCN1 pore and scaffolds were also identified. Moreover, ADME predictions revealed that compounds had good oral bioavailability and solubility characteristics. Subsequently, molecular dynamics simulation studies revealed the better stability of the lead molecules A7 and A9 during interactions and ascertained them as potential drug candidates. Cumulative studies provided the important structural features for enhancing HCN1 channel-specific inhibition, paving the way to design and develop novel specific HCN1 channel inhibitors.
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Parkinson's disease (PD) is an age-related chronic neurological condition characterized by progressive degeneration of dopaminergic neurons and the presence of Lewy bodies, primarily composed of alpha-synuclein and ubiquitin. The pathophysiology of PD encompasses alpha-synuclein aggregation, oxidative stress, neuroinflammation, mitochondrial dysfunction, and impaired autophagy and ubiquitin-proteasome systems. Among these, the Keap1-Nrf2 pathway is a key regulator of antioxidant defense mechanisms. Nrf2 has emerged as a crucial factor in managing oxidative stress and inflammation, and it also influences ubiquitination through p62 expression. Keap1 negatively regulates Nrf2 by targeting it for degradation via the ubiquitin-proteasome system. Disruption of the Nrf2-Keap1 pathway in PD affects cellular responses to oxidative stress and inflammation, thereby playing a critical role in disease progression. In addition, the role of neuroinflammation in PD has gained significant attention, highlighting the interplay between immune responses and neurodegeneration. This review discusses the various mechanisms responsible for neuronal degeneration in PD, with a special emphasis on the neuroprotective role of the Nrf2-Keap1 pathway. Furthermore, it explores the implications of inflammopharmacology in modulating these pathways to provide therapeutic insights for PD.
Assuntos
Proteína 1 Associada a ECH Semelhante a Kelch , Fator 2 Relacionado a NF-E2 , Neuroproteção , Estresse Oxidativo , Doença de Parkinson , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Doença de Parkinson/metabolismo , Doença de Parkinson/tratamento farmacológico , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Animais , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Neuroproteção/fisiologia , Transdução de Sinais/fisiologia , Fármacos Neuroprotetores/farmacologia , Inflamação/metabolismo , Inflamação/tratamento farmacológicoRESUMO
BACKGROUND: Morbidity and mortality rates associated with acute lung injury/acute respiratory distress syndrome (ALI/ARDS) are high (30-40%). Nuclear factor-kappa B (NF-κB) is a transcription factor, associated with transcription of numerous cytokines leading to cytokine storm, and thereby, plays a major role in ALI/ARDS and in advanced COVID-19 syndrome. METHODS: Considering the role of NF-κB in ALI, cost-effective in silico approaches were utilized in the study to identify potential NF-κB inhibitor based on the docking and pharmacokinetic results. The identified compound was then pharmacologically validated in lipopolysaccharide (LPS) rodent model of acute lung injury. LPS induces ALI by altering alveolar membrane permeability, recruiting activated neutrophils and macrophages to the lungs, and compromising the alveolar membrane integrity and ultimately impairs the gaseous exchange. Furthermore, LPS exposure is associated with exaggerated production of various proinflammatory cytokines in lungs. RESULTS: Based on in silico studies Olopatadine Hydrochloride (Olo), an FDA-approved drug was found as a potential NF-κB inhibitor which has been reported for the first time, and considered further for the pharmacological validation. Intraperitoneal LPS administration resulted in ALI/ARDS by fulfilling 3 out of the 4 criteria described by ATS committee (2011) published workshop report. However, treatment with Olo attenuated LPS-induced elevation of proinflammatory markers (IL-6 and NF-κB), oxidative stress, neutrophil infiltration, edema, and damage in lungs. Histopathological studies also revealed that Olo treatment significantly ameliorated LPS-induced lung injury, thus conferring improvement in survival. Especially, the effects produced by Olo medium dose (1 mg/kg) were comparable to dexamethasone standard. CONCLUSION: In nutshell, inhibition of NF-κB pathway by Olo resulted in protection and reduced mortality in LPS- induced ALI and thus has potential to be used clinically to arrest disease progression in ALI/ARDS, since the drug is already in the market. However, the findings warrant further extensive studies, and also future studies can be planned to elucidate its role in COVID-19-associated ARDS or cytokine storm.
Assuntos
Lesão Pulmonar Aguda , COVID-19 , Síndrome do Desconforto Respiratório , Humanos , NF-kappa B , Lipopolissacarídeos/farmacologia , Cloridrato de Olopatadina , Síndrome da Liberação de Citocina , Transdução de Sinais , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Proteínas I-kappa B , CitocinasRESUMO
Excessive activation of α-amino-3-hydroxy-5-methyl-4-isoxazole propoinic acid (AMPA) receptors instigates excitotoxicity via enhanced calcium influx in the neurons thus inciting deleterious consequences. Additionally, Endoplasmic Reticulum (ER) is pivotal in maintaining the intracellular calcium balance. Considering this, studying the aftermath of enhanced calcium uptake by neurons and its effect on ER environment can assist in delineating the pathophysiological events incurred by excitotoxicty. The current study was premeditated to decipher the role of ER pertaining to calcium homeostasis in AMPA-induced excitotoxicity. The findings showed, increased intracellular calcium levels (measured by flowcytometry and spectroflourimeter using Fura 2AM) in AMPA excitotoxic animals (male Sprague dawely rats) (intra-hippocampal injection of 10 mM AMPA). Further, ER resident proteins like calnexin, PDI and ERp72 were found to be upregulated, which further modulated the functioning of ER membrane calcium channels viz. IP3R, RyR, and SERCA pump. Altered calcium homeostasis further led to ER stress and deranged the protein folding capacity of ER post AMPA toxicity, which was ascertained by unfolded protein response (UPR) pathway markers such as IRE1α, eIF2α, and ATF6α. Chemical chaperone, 4-phenybutric acid (4-PBA), ameliorated the protein folding capacity and subsequent UPR markers. In addition, modulation of calcium channels and calcium regulating machinery of ER post 4-PBA administration restored the calcium homeostasis. Therefore the study reinforces the significance of ER stress, a debilitating outcome of impaired calcium homeostasis, under AMPA-induced excitotoxicity. Also, employing chaperone-based therapeutic approach to curb ER stress can restore the calcium imbalance in the neuropathological diseases.
Assuntos
Cálcio , Endorribonucleases , Masculino , Ratos , Animais , Cálcio/metabolismo , Endorribonucleases/metabolismo , Endorribonucleases/farmacologia , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/metabolismo , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Neurônios/metabolismo , Receptores de AMPA/metabolismo , Canais de Cálcio/metabolismoRESUMO
Alzheimer's disease (AD) is a heterogeneous neurodegenerative disorder with complex etiology that eventually leads to dementia. The main culprit of AD is the extracellular deposition of ß-amyloid (Aß) and intracellular neurofibrillary tangles. The protein conformational change and protein misfolding are the key events of AD pathophysiology; therefore, endoplasmic reticulum (ER) stress is an apparent consequence. ER, stress-induced unfolded protein response (UPR) mediators (viz. PERK, IRE1, and ATF6) have been reported widely in the AD brain. Considering these factors, preventing protein misfolding or aggregation of tau or amyloidogenic proteins appears to be the best approach to halt its pathogenesis. Therefore, therapies through chemical and pharmacological chaperones came to light as an alternative for the treatment of AD. Diverse studies have demonstrated 4-phenylbutyric acid (4-PBA) as a potential therapeutic agent in AD. The current review outlined the mechanism of protein misfolding, different etiological features behind the progression of AD, the significance of ER stress in AD, and the potential therapeutic role of different chaperones to counter AD. The study also highlights the gaps in current knowledge of the chaperones-based therapeutic approach and the possibility of developing chaperones as a potential therapeutic agent for AD treatment.
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Doença de Alzheimer , Humanos , Doença de Alzheimer/metabolismo , Transdução de Sinais , Estresse do Retículo Endoplasmático/fisiologia , Resposta a Proteínas não Dobradas , Peptídeos beta-Amiloides/metabolismo , Chaperonas Moleculares/uso terapêuticoRESUMO
Glutamate excitotoxicity and endoplasmic reticulum (ER) recently have been found to be instrumental in the pathogenesis of various neurodegenerative diseases. However, the paucity of literature deciphering the inter-linkage among glutamate receptors, behavioral alterations, and ER demands thorough exploration. Reckoning the aforesaid concerns, a prospective study was outlined to delineate the influence of ER stress inhibition via 4-phenylbutyric acid (PBA) on α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) excitotoxicity-induced behavioral aspects and possible ER stress-glutamate linkage. Male SD rats were randomly divided into four groups namely sham (surgical control+vehicle, group 1), AMPA-induced excitotoxic group 2 receive a single intra-hippocampal injection of 10 mM AMPA, group 3 received AMPA along with PBA (i.p, 100 mg/kg body weight) for 15 days, and group 4 received PBA alone. Behavioral analyses were performed prior to the sacrifice of animals and hippocampus was extracted thereafter for further analysis. AMPA-induced excitotoxicity exhibited significant impairment of locomotion as well as cognitive functions. The levels of neurotransmitters such as dopamine, homo vanillic acid (HVA), norepinephrine, and serotonin were reduced accompanied by reduced expression of GLUR1 and GLUR4 (glutamate receptor) as well as loss of neurons in different layers of hippocampus. ER stress markers were upregulated upon AMPA excitotoxicity. However, chemical chaperone PBA supplementation remarkably mitigated the behavioral alterations along with expression of glutamate and ER stress intermediates/markers in AMPA excitotoxic animals. Therefore, the present exploration convincingly emphasizes the significance of ER stress and its inhibition via PBA in combating cognitive impairment as well as improving locomotion in excitotoxic animals.
Assuntos
Butilaminas/farmacologia , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/prevenção & controle , Estresse do Retículo Endoplasmático/fisiologia , Agonistas de Aminoácidos Excitatórios/toxicidade , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/toxicidade , Animais , Butilaminas/uso terapêutico , Disfunção Cognitiva/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
PURPOSE: Hyperoxaluria-induced calcium oxalate crystallisation is associated with the generation of reactive oxygen species (ROS) via mitochondria and NADPH oxidase. Endoplasmic reticulum (ER) has emerged as an organelle which could influence mitochondrial functioning and ROS generation. Plugging an upstream pathway of mitochondrial and NADPH oxidase-induced ROS generation may have better prophylaxis. Therefore, we propose to investigate the linkage of hyperoxaluria-induced ROS generation with ER stress by inhibiting the later with 4-Phenylbutyric acid (4-PBA). METHODS: Male wistar rats were divided into three groups: a normal control group, an ethylene glycol with ammonium chloride-induced hyperoxaluric group (EA) and a third group which has hyperoxaluric animals given 4-PBA at a dose of 300 mg/kg. After 9 days of treatment, animals were sacrificed and renal tissues were analysed for histopathological examination, ROS, mitochondrial dysfunction, ER stress markers, inflammatory markers and NADPH oxidase subunits expression. RESULTS: Hyperoxaluric rats exhibited a significant increase in the levels of ROS, subsequently up-regulated levels of ER stress markers, inflammatory indicators, NADPH oxidase subunits and compromised mitochondrial functioning. However, ER stress amelioration appreciably curtailed the alterations caused by hyperoxaluric abuse. CONCLUSIONS: Therefore, suggesting the major role of ER in hyperoxaluric manifestations thereby providing an opportunity to target ER stress for future therapeutic interventions.
Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Hiperoxalúria/metabolismo , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fenilbutiratos/farmacologia , Animais , Antioxidantes/farmacologia , Oxalato de Cálcio/química , Oxalato de Cálcio/metabolismo , Cristalização , Masculino , NADPH Oxidases/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismoRESUMO
Hyperoxaluria is a stress that leads to calcium oxalate crystal deposition which further causes inflammation and renal cell necroptosis. Many studies have linked osteopontin expression with apoptosis and inflammation but so far its association with apoptosis with regard to hyperoxaluria is undiscovered. Moreover, a recent report has suggested that osteopontin induces endoplasmic reticulum stress and subsequently apoptosis in myocytes. In this study, the impact of hyperoxaluria on the modulation of osteopontin expression and endoplasmic reticulum (ER) stress mediated apoptosis in rats is explored. Hyperoxaluria was induced in rats by three different doses viz. ethylene glycol alone, ethylene glycol and ammonium chloride together and third group were fed with hydroxyl-l-proline. After hyperoxaluria induction rats were sacrificed and renal tissue was analysed for crystal depositions, osteopontin expression, inflammation, ER stress and subsequent unfolded protein response intermediates (UPR). Altered histoarchitecture of renal tissue and elevated levels of reactive oxygen species (ROS) along with the presence of calcium oxalate crystals were observed in the hyperoxaluric groups. As expected, inflammation and apoptosis was significantly high in all hyperoxaluria groups. Osteopontin expression showed significant up-regulation following hyperoxaluria. Further, a similar trend between expression of osteopontin and elevated ER stress level was observed. Moreover, UPR intermediates expression was also concurrent with osteopontin levels. It is observed that the extent of calcium oxalate crystal deposition is directly associated with the expression of osteopontin, inflammation and ER stress. The results advocate possible association of osteopontin with ER stress, thus suggesting that the ER could be a new target for developing therapeutic regimes for kidney stones.
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Apoptose , Estresse do Retículo Endoplasmático/genética , Hiperoxalúria/patologia , Rim/patologia , Osteopontina/metabolismo , Animais , Oxalato de Cálcio/metabolismo , Modelos Animais de Doenças , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Masculino , Osteopontina/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Resposta a Proteínas não Dobradas , Regulação para CimaRESUMO
The purpose of the present study was to evaluate the nephro-protective potential of N-acetylcysteine against hyperoxaluria-induced renal mitochondrial dysfunction in rats. Nine days dosing of 0.4 % ethylene glycol +1 % ammonium chloride, developed hyperoxaluria in male wistar rats which resulted in renal injury and dysfunction as supported by increased level of urinary lactate dehydrogenase, calcium, and decreased creatinine clearance. Mitochondrial oxidative strain in hyperoxaluric animals was evident by decreased levels of superoxide dismutase, glutathione peroxidase, glutathione reductase, reduced glutathione, and an increased lipid peroxidation. Declined activities of respiratory chain enzymes and tricarboxylic acid cycle enzymes showed mitochondrial dysfunction in hyperoxaluric animals. N-acetylcysteine (50 mg/kg, i.p.), by virtue of its -SH reviving power, was able to increase the glutathione levels and thus decrease the oxidative stress in renal mitochondria. Hence, mitochondrial damage is, evidently, an essential event in ethylene glycol-induced hyperoxaluria and N-acetylcysteine presented itself as a safe and effective remedy in combating nephrolithiasis.
Assuntos
Acetilcisteína/farmacologia , Hiperoxalúria/fisiopatologia , Mitocôndrias/efeitos dos fármacos , Doenças Mitocondriais/tratamento farmacológico , Substâncias Protetoras/farmacologia , Animais , Cálcio/urina , Ciclo do Ácido Cítrico/efeitos dos fármacos , Creatinina/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Hiperoxalúria/metabolismo , Hiperoxalúria/urina , Rim/metabolismo , Rim/fisiopatologia , L-Lactato Desidrogenase/urina , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Mitocôndrias/metabolismo , Doenças Mitocondriais/metabolismo , Doenças Mitocondriais/fisiopatologia , Doenças Mitocondriais/urina , Nefrolitíase/metabolismo , Nefrolitíase/fisiopatologia , Nefrolitíase/urina , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismoRESUMO
In response to hypobaric hypoxia (HH), which occurs at high altitude, the brain undergoes deleterious changes at the structural and metabolite level. In vivo T2 weighted imaging (T2WI) and (1)H-MRS was performed to understand the structural and metabolic changes in the hippocampus region of rat brain. Data were acquired pre-exposure (baseline controls), immediately after exposure and subsequently at the first, fourth, seventh and 14th days post exposure at normoxia. T2 weighted images of rat brain showed hyperintensity in the CA2/CA3 region of the hippocampus 7 d after acute HH, which persisted till 14 d, probably indicating structural changes in the hippocampus. (1)H-MRS results showed no change in metabolite level immediately after acute HH exposure, but on the first day of normoxia the myo-inositol level was significantly decreased, possibly due to altered astrocyte metabolism. Metabolic alterations showing an increase in choline and decrease in glutamate on the fourth day of normoxia may be seen as a process of demyelination and loss of glutamate pool respectively. On the seventh and 14th days of normoxia, decreases in N-acetylaspartate, creatine and glutamine + glutamate were observed, which might be due to decreased viability of glutamatergic neurons. In vivo (1)H-MRS demonstrated early neurometabolic changes prior to probable structural changes post acute HH exposure. The extension of these studies will help in early risk assessment, developing intervention and strategies for combating HH related changes.
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Encéfalo/metabolismo , Encéfalo/patologia , Hipóxia/metabolismo , Hipóxia/patologia , Espectroscopia de Ressonância Magnética , Prótons , Doença Aguda , Animais , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Metaboloma , Ratos , Ratos Sprague-Dawley , Fatores de TempoRESUMO
The abnormal accumulation of fibrillar α-synuclein in the substantia nigra contributes to Parkinson's disease (PD). Chemical chaperones like 4-phenyl butyric acid (4PBA) show neuroprotective potential, but high doses are required. A derivative, 5-phenyl valeric acid (5PVA), has reported therapeutic potential for PD by reducing Pael-R expression. This study assessed 5PVA's efficacy in PD animals and its molecular mechanism. In vitro studies revealed 5PVA's anti-aggregation ability against alpha-synuclein and neuroprotective effects on SHSY5Y neuroblastoma cells exposed to rotenone. PD-like symptoms were induced in SD rats with rotenone, followed by 5PVA treatment at 100 mg/kg and 130 mg/kg. Behavioral analysis showed significant improvement in memory and motor activity with 5PVA administration. Histopathological studies demonstrated normal neuronal histoarchitecture in mid-brain tissue sections of 5PVA-treated animals compared to the PD group. mRNA studies revealed significant suppression in the expression of various protein folding and heat-shock protein markers in the 5PVA-treated group. In conclusion, 5PVA, with its anti-aggregation ability against alpha-synuclein, acts as a chemical chaperone, showing potential as a therapeutic candidate for PD treatment.
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Estresse do Retículo Endoplasmático , Ratos Sprague-Dawley , Rotenona , alfa-Sinucleína , Animais , alfa-Sinucleína/metabolismo , Rotenona/toxicidade , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ratos , Masculino , Linhagem Celular Tumoral , Humanos , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Ácidos Pentanoicos/farmacologia , Ácidos Pentanoicos/uso terapêutico , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/tratamento farmacológico , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/patologia , Agregados Proteicos/efeitos dos fármacosRESUMO
Linalool is a neuroprotective monoterpene found in essential oils from aromatic plants. Linalool's effectiveness in AD animal models has been established previously, but its mechanisms of action remain unclear. Therefore, this study aims to investigate whether linalool binds directly to the amyloid beta (Aß) fibrils to understand it's role in preventing neurodegeneration. The anti-aggregation ability of Linalool was determined using Dithiothreitol (DTT), and thermal aggregation assays followed by Thioflavin T (ThT) binding assay. AD animals were treated with Linalool, and Thioflavin T staining was used to check the binding of linalool to Aß fibrils in rat brain tissue sections. Preliminary studies revealed the anti-aggregation potential of linalool under the thermal and chemical stimulus. Further, in ThT binding assay Linalool inhibited Aß aggregation, binding directly to Aß fibrils. The reduced fluorescence intensity of ThT in AD brain tissues following linalool administration, highlights its neuroprotective potential as a therapeutic agent for AD.
Assuntos
Monoterpenos Acíclicos , Peptídeos beta-Amiloides , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Monoterpenos Acíclicos/farmacologia , Animais , Ratos , Masculino , Monoterpenos/farmacologia , Monoterpenos/uso terapêutico , Monoterpenos/química , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Fármacos Neuroprotetores/farmacologia , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Ratos Wistar , Agregados Proteicos/efeitos dos fármacos , Agregados Proteicos/fisiologia , Ratos Sprague-Dawley , Agregação Patológica de Proteínas/tratamento farmacológico , Agregação Patológica de Proteínas/metabolismo , Agregação Patológica de Proteínas/prevenção & controleRESUMO
The Endoplasmic reticulum (ER), a critical cellular organelle, maintains cellular homeostasis by regulating calcium levels and orchestrating essential functions such as protein synthesis, folding, and lipid production. A pivotal aspect of ER function is its role in protein quality control. When misfolded proteins accumulate within the ER due to factors like protein folding chaperone dysfunction, toxicity, oxidative stress, or inflammation, it triggers the Unfolded protein response (UPR). The UPR involves the activation of chaperones like calnexin, calreticulin, glucose-regulating protein 78 (GRP78), and Glucose-regulating protein 94 (GRP94), along with oxidoreductases like protein disulphide isomerases (PDIs). Cells employ the Endoplasmic reticulum-associated degradation (ERAD) mechanism to counteract protein misfolding. ERAD disruption causes the detachment of GRP78 from transmembrane proteins, initiating a cascade involving Inositol-requiring kinase/endoribonuclease 1 (IRE1), Activating transcription factor 6 (ATF6), and Protein kinase RNA-like endoplasmic reticulum kinase (PERK) pathways. The accumulation and deposition of misfolded proteins within the cell are hallmarks of numerous neurodegenerative diseases. These aberrant proteins disrupt normal neuronal signalling and contribute to impaired cellular homeostasis, including oxidative stress and compromised protein degradation pathways. In essence, ER stress is defined as the cellular response to the accumulation of misfolded proteins in the endoplasmic reticulum, encompassing a series of signalling pathways and molecular events that aim to restore cellular homeostasis. This comprehensive review explores ER stress and its profound implications for the pathogenesis and progression of neurodegenerative diseases.
Assuntos
Doenças Neurodegenerativas , Humanos , Chaperona BiP do Retículo Endoplasmático , Degradação Associada com o Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Resposta a Proteínas não Dobradas , Chaperonas Moleculares , GlucoseRESUMO
Aggregated α-synuclein (α-syn) present inside small cytoplasmic inclusions in the substantia nigra region marks the major pathological hallmark of Parkinson's disease (PD) and makes it an attractive target for the drug development process. Certain small-molecule chaperones (such as DCA, UDCA, TUDCA) presented the ability to prevent misfolding and aggregation of α-syn as well as to disentangle mature α-syn amyloid fibrils. However, due to toxicity constraints, these small molecules could not be translated into clinical settings. Computational biology methods and bioinformatics approaches allow virtual screening of a large number of molecules, with reduced side effects and better efficacy. In the present study, a library of 10,928 derivatives was generated using DCA, UDCA, and TUDCA bile acid scaffolds and analysed for their binding affinity, pharmacokinetic properties, and drug likeliness profile, to come up with promising compounds with reduced toxicity and better chaperone ability. Molecular docking revealed that with respect to their free binding energy, C1-C25 have the lowest binding energy and bind significantly to recombinantly assembled E46K α-syn fibrils (PDB ID-6UFR). In silico ADME predictions revealed that all these compounds had minimal toxic effects and had good absorption as well as solubility characteristics. Simulation studies further showed that the imidazole ring-based TUDCA derivatives interacted better with the protein in comparison to the others. The proposed study has identified potent chemical chaperones (C2 and C3) as effective therapeutic agents for Parkinson's disease, and further in vitro and in vivo testing will be undertaken to substantiate their potential as novel drugs.
RESUMO
AIM: Urinary glycoproteins such as Tamm Horsfall Protein (THP) and Osteopontin (OPN) are well established key regulators of renal stone formation. Additionally, recent revelations have highlighted the influence of Endoplasmic Reticulum (ER) and mitochondria of crucial importance in nephrolithiasis. However, till date conclusive approach highlighting the influence of ER stress on urinary glycoproteins and chaperone in nephrolithiasis remains elusive. Therefore, the present study was focussed on deciphering the possible effect of 4-PBA mitigating ER stress on urinary glycoproteins and calnexin (chaperone) with emphasis on interlinking calcium homeostasis in hyperoxaluric rats. MATERIAL AND METHODS: Post 9 days of treatment, animals were sacrificed, and renal tissues were investigated for urinary glycoproteins, calnexin, calcium homeostasis, ER environment, redox status, and mitochondrial linkage. KEY FINDINGS: 4-PBA appreciably reversed the altered levels of THP, OPN, and calnexin observed along with curtailing the disrupted calcium homeostasis when assessed for SERCA activity and intra-cellular calcium levels. Additionally, significant improvement in the perturbed ER environment as verified by escalated ER stress markers, disturbed protein folding-aggregation-degradation (congo red assay) pathway, and redox status was found post 4-PBA intervention. Interestingly, linkage of ER stress and mitochondria was established under hyperoxaluric conditions when assessed for protein levels of VDAC1 and GRP75. SIGNIFICANCE: 4-PBA treatment resulted in rectifying the repercussions of ER-mitochondrial caused distress when assessed for protein folding/aggregation/degradation events along with disturbed calcium homeostasis. The present study advocates the necessity to adopt a holistic vision towards hyperoxaluria with emphasis on glycoproteins and ER environment.
Assuntos
Hiperoxalúria , Cálculos Renais , Animais , Butilaminas , Cálcio/metabolismo , Calnexina/metabolismo , Calnexina/farmacologia , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Glicoproteínas/metabolismo , Homeostase , Cálculos Renais/etiologia , Cálculos Renais/metabolismo , Mitocôndrias/metabolismo , Chaperonas Moleculares/metabolismo , RatosRESUMO
Oxalate exposure to human renal epithelial cells triggers a vicious cycle of oxidative stress leading to cellular injury and deposition of calcium oxalate crystals on the injured cells. This results in further oxidative damage causing inflammation and loss of cell-cell adhesion factors, ultimately leading to irreparable kidney damage. However, these events can be attenuated or prevented by plants rich in antioxidants used in the traditional system of medicine for treatment of kidney stones. To delineate the mechanism by which Bergenia ligulata extract exerts its cytoprotective role in oxalate-induced injury we designed this study. Our results revealed that oxalate-injured HK2 cells cotreated with ethanolic extract of Bergenia ligulata displayed increased viability, reduced oxidative stress due to lowered production of intracellular reactive oxygen species (ROS) and decreased apoptosis. We also observed lowered markers of inflammation, along with increased expression of epithelial marker E-cadherin and decreased expression of mesenchymal markers Vimentin, F-actin, Transforming growth factor beta 1 (TGF-ß1) and EMT-related proteins in renal tubular epithelial cells through immunocytochemistry, real-time PCR and western blotting. Our findings collectively suggest that by reducing oxidative stress, modulating crystal structure and preventing crystal-cell adhesion, B. ligulata inhibits the EMT pathway by downregulating the various mediators and thereby exerts its cytoprotective effect.
Assuntos
Transição Epitelial-Mesenquimal , Cálculos Renais , Células Epiteliais/metabolismo , Feminino , Humanos , Inflamação , Cálculos Renais/induzido quimicamente , Cálculos Renais/tratamento farmacológico , Cálculos Renais/prevenção & controle , Masculino , Oxalatos/metabolismo , Estresse Oxidativo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/farmacologiaRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: In the Indian traditional system of medicine, Bergenia ligulata (Wall.) Engl. has been used for treatment of urolithiasis. Its efficacious nature has led to its incorporation in various commercial herbal formulations such as Cystone and Neeri which are prescribed for kidney related ailments. AIM OF THE STUDY: To assess whether ethanolic extract of B. ligulata can mitigate the cascade of inflammatory responses that cause oxidative stress and ultimately cell death in renal epithelial cells exposed to hyperoxaluric conditions. MATERIAL AND METHODS: Bioactivity guided fractionation using solvents of varying polarities was employed to evaluate the potential of the extracts of B. ligulata to inhibit the crystallization process. Modulation of crystal morphology was visualized through Scanning electron microscopy (SEM) analysis. Cell death was assessed using flow cytometry based assays. Alteration in the inflammatory mediators was evaluated using real time PCR and immunocytochemistry. Phytochemical characterization of the ethanolic extract was carried out using FTIR, LC-MS and GC-MS. RESULTS: Bioactivity guided fractionation for the assessment of antilithiatic activity revealed dose dependent inhibition of nucleation and aggregation process of calcium oxalate crystals in the presence of various extracts, however ethanolic extract showed maximum inhibition and was chosen for further experiments. Studies on renal epithelial NRK-52E cells showed, cytoprotective efficacy of B. ligulata extract against oxalate injury. SEM anaysis further revealed the potential of the extract to modulate the crystal structure and adhesion to renal cell surface. Exposure of the renal cells to the extract led to conversion of the calcium oxalate monohydrate (COM) crystals to the less injurious calcium oxalate dihydrate (COD) form. Expression analysis for oxidative stress and inflammatory biomarkers in NRK-52E cells revealed up-regulation of Mitogen activated protein kinase (MAPK), Osteopontin (OPN) and Nuclear factor- ĸB (NF-ĸB), in response to calcium oxalate insult; which was drastically reduced in the presence of B. ligulata extract. Flow cytometric evaluation pointed to caspase 3 mediated apoptotic cell death in oxalate injured cells, which was attenuated by B. ligulata extract. CONCLUSION: Considering the complex multifactorial etiology of urolithiasis, ethanolic extract from B. ligulata can be a promising option for the management of kidney stones, as it has the potential to limit inflammation and the subsequent cell death.
Assuntos
Injúria Renal Aguda/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Células Epiteliais/metabolismo , Mediadores da Inflamação/metabolismo , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Saxifragaceae/química , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/genética , Animais , Apoptose/efeitos dos fármacos , Oxalato de Cálcio/antagonistas & inibidores , Oxalato de Cálcio/química , Oxalato de Cálcio/toxicidade , Caspase 3/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Etanol , Índia , Medicina Tradicional , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Osteopontina/metabolismo , Extratos Vegetais/química , Substâncias Protetoras/química , Ratos , Urolitíase/tratamento farmacológicoRESUMO
On-going pandemic pneumonia outbreak COVID-19 has raised an urgent public health issue worldwide impacting millions of people with a continuous increase in both morbidity and mortality. The causative agent of this disease is identified and named as SARS-CoV2 because of its genetic relatedness to SARS-CoV species that was responsible for the 2003 coronavirus outbreak. The immense spread of the disease in a very small period demands urgent development of therapeutic and prophylactic interventions for the treatment of SARS-CoV2 infected patients. A plethora of research is being conducted globally on this novel coronavirus strain to gain knowledge about its origin, evolutionary history, and phylogeny. This review is an effort to compare genetic similarities and diversifications among coronavirus strains, which can hint towards the susceptible antigen targets of SARS-CoV2 to come up with the potential therapeutic and prophylactic interventions for the prevention of this public threat.
Assuntos
Vacinas contra COVID-19/imunologia , Genes Virais , SARS-CoV-2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Especificidade da Espécie , Proteínas Virais/genéticaRESUMO
OBJECTIVE: Methylphenidate (MPH) is a first-line treatment option for attention-deficit hyperactive disorder and narcolepsy. MPH is one of the most abused psychostimulants by the adults and young population to stay awake, perform better, or improve concentration. The scanty reports say that the medical users or abusers mostly consider the administration of benzodiazepines to overcome the adverse effects, i.e., mood- and anxiety-related problems associated with MPH chronic abuse. This work aims to study the effect of alprazolam (ALZ) on MPH-associated adverse effects on liver and kidney. MATERIALS AND METHODS: Female Wistar rats (n = 58) were administered with MPH (10, 20, and 40 mg/kg) and ALZ (5, 10, and 20 mg/kg) alone and in combination for 28 days. Bodyweight, feed intake, and water intake were monitored weekly. Parameters related to liver and renal function, oxidative stress, and histopathology were performed to evaluate the toxic impacts on the liver and kidneys. RESULTS: ALZ, along with MPH, increased the serum alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, creatinine, and urea levels. The co-abuse also led to elevated oxidative stress and structural abnormalities in the liver and kidney tissues. CONCLUSION: The co-abuse of ALZ has amplified the hepato-renal toxic effects of MPH. Therefore, it is a significant concern for public safety, and their co-abuse must be restricted and discouraged.
Assuntos
Alprazolam/toxicidade , Estimulantes do Sistema Nervoso Central/toxicidade , Hipnóticos e Sedativos/toxicidade , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Metilfenidato/toxicidade , Transtornos Relacionados ao Uso de Substâncias/complicações , Animais , Modelos Animais de Doenças , Feminino , Rim/metabolismo , Rim/patologia , Fígado/metabolismo , Fígado/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar , Transtornos Relacionados ao Uso de Substâncias/metabolismo , Transtornos Relacionados ao Uso de Substâncias/patologiaRESUMO
BACKGROUND: In the previous decade, abuse of several types of prescription drugs, particularly anxiolytics, opioid analgesics, and stimulants has increased significantly worldwide. Methylphenidate (MPH) and Alprazolam (ALZ) are extensively used drugs for the treatment of attention deficit hyperactivity disorder (ADHD) and anxiety disorders, respectively. However, these drugs have a high risk of being misused or abused alone, and their combination in some peculiar cases has shown their deleterious effects. In this study, we evaluated the extent of damage both these drugs (MPH and ALZ) may cause in the brain at different dosages. METHODS: Female Wistar rats were administered with MPH (10, 20, 40mg/kg) and ALZ (5, 10, 20mg/kg) alone and in combination. Following the treatment, neurobehavioral studies were conducted, and later brain tissue was removed for studying the extent of oxidative stress and inflammation in the hippocampus and cortex region of the brain. Further histopathological parameters, along with neurotransmitter levels, were also assessed. RESULTS: Both MPH and ALZ, in combination, enhanced oxidative stress, inflammation, and neurobehavioral alterations in a dose-dependent manner. These toxic effects were associated with histopathological alterations and neurotransmitters levels CONCLUSIONS: In this study, it is found that the combination of psychostimulant (MPH) and depressant (ALZ) tends to enhance toxicity in the brain, and their long-term usage is a significant public health concern. Therefore, their co-administration should be strictly monitored by medical practitioners, and under compulsive circumstances, their use must be restricted to lower doses.