RESUMO
Erigeron bonariensis is widely distributed throughout the world's tropics and subtropics. In folk medicine, E. bonariensis has historically been used to treat head and brain diseases. Alzheimer's disease (AD) is the most widespread form of dementia initiated via disturbances in brain function. Herein, the neuroprotective effect of the chemically characterized E. bonariensis ethanolic extract is reported for the first time in an AD animal model. Chemical profiling was conducted using UPLC-ESI-MS analysis. Female rats underwent ovariectomy (OVX) followed by 42 days of D-galactose (D-Gal) administration (150 mg/kg/day, i.p) to induce AD. The OVX/D-Gal-subjected rats received either donepezil (5 mg/kg/day) or E. bonariensis at 50, 100, and 200 mg/kg/day, given 1 h prior to D-Gal. UPLC-ESI-MS analysis identified 42 chemicals, including flavonoids, phenolic acids, terpenes, and nitrogenous constituents. Several metabolites, such as isoschaftoside, casticin, velutin, pantothenic acid, xanthurenic acid, C18-sphingosine, linoleamide, and erucamide, were reported herein for the first time in Erigeron genus. Treatment with E. bonariensis extract mitigated the cognitive decline in the Morris Water Maze test and the histopathological alterations in cortical and hippocampal tissues of OVX/D-Gal-subjected rats. Moreover, E. bonariensis extract mitigated OVX/D-Gal-induced Aß aggregation, Tau hyperphosphorylation, AChE activity, neuroinflammation (NF-κBp65, TNF-α, IL-1ß), and apoptosis (Cytc, BAX). Additionally, E. bonariensis extract ameliorated AD by increasing α7-nAChRs expression, down-regulating GSK-3ß and FOXO3a expression, and modulating Jak2/STAT3/NF-ĸB p65 and PI3K/AKT signaling cascades. These findings demonstrate the neuroprotective and memory-enhancing effects of E. bonariensis extract in the OVX/D-Gal rat model, highlighting its potential as a promising candidate for AD management.
Assuntos
Doença de Alzheimer , Erigeron , Fármacos Neuroprotetores , Ratos , Feminino , Animais , Ratos Wistar , Galactose/efeitos adversos , Cromatografia Líquida de Alta Pressão , Fosfatidilinositol 3-Quinases , Glicogênio Sintase Quinase 3 beta , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêuticoRESUMO
Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder attributed to several etiological factors including cholinergic dysregulation, neuroinflammation, oxidative stress, ß-amyloidogenesis, and tauopathy. This demands the search for multitarget drugs, especially of natural sources owing to their pleiotropic activities and low adverse effects. The present study was conducted to investigate the cognitive-improving potential of Ceratonia siliqua L. (Cs) extract compared with donepezil, an acetylcholinesterase inhibitor, on AD-like pathological alterations induced by single intracerebroventricular amyloid-ß42 (Aß42) injection in mice. Aß42-injected mice were treated with Cs (100 mg/kg/day, po) with or without methyllycaconitine (MLA; 1 mg/kg/day, ip), an α7-nAChR antagonist. Aß42-injected animals demonstrated an elevation of hippocampal Aß42, p-Tau, and acetylcholinesterase. They also showed a decline in phosphorylated levels of Jak2, PI3K, Akt, and GSK-3ß, leading to induction of neuroinflammation and oxidative stress. Noteworthy, Cs improved the histopathological and behavioral variables in addition to mitigating AD hallmarks. It also exerted neuroprotection by reducing NF-κBp65 and TNF-α, while elevating Nrf2 and HO-1, along with stabilizing ß-catenin under the impact of Jak2/PI3K/Akt/GSK-3ß signaling. These beneficial effects of Cs were abrogated by MLA co-administration signifying the α7-nAChR involvement in Cs-mediated effects. Therefore, Cs can ameliorate Aß42-induced neurodegeneration by modulating Jak2/PI3K/Akt/GSK-3ß/ß-catenin axis in an α7-nAChR-dependent manner.
Assuntos
Doença de Alzheimer , Proteínas Proto-Oncogênicas c-akt , Camundongos , Animais , Glicogênio Sintase Quinase 3 beta , Antioxidantes/farmacologia , Fosfatidilinositol 3-Quinases , Doenças Neuroinflamatórias , beta Catenina , Acetilcolinesterase , Peptídeos beta-Amiloides/toxicidade , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Anti-Inflamatórios , CogniçãoRESUMO
Nociplastic pain is the third classification of pain as described by the International Association for the Study of Pain (IASP), in addition to the neuropathic and nociceptive pain classes. The main pathophysiological mechanism for developing nociplastic pain is central sensitization (CS) in which pain amplification and hypersensitivity occur. Fibromyalgia is the prototypical nociplastic pain disorder, characterized by allodynia and hyperalgesia. Much scientific data suggest that classical activation of microglia in the spinal cord mediates neuroinflammation which plays an essential role in developing CS. In this review article, we discuss the impact of microglia activation and M1/M2 polarization on developing neuroinflammation and nociplastic pain, besides the molecular mechanisms engaged in this process. In addition, we mention the impact of microglial modulators on M1/M2 microglial polarization that offers a novel therapeutic alternative for the management of nociplastic pain disorders. Illustrating the mechanisms underlying microglia activation in central sensitization and nociplastic pain. LPS lipopolysaccharide, TNF-α tumor necrosis factor-α, INF-γ Interferon gamma, ATP adenosine triphosphate, 49 P2Y12/13R purinergic P2Y 12/13 receptor, P2X4/7R purinergic P2X 4/7 receptor, SP Substance P, NK-1R Neurokinin 1 receptor, CCL2 CC motif ligand 2, CCR2 CC motif ligand 2 receptor, CSF-1 colony-stimulating factor 1, CSF-1R colony-stimulating factor 1 receptor, CX3CL1 CX3C motif ligand 1, CX3XR1 CX3C motif ligand 1 receptor, TLR toll-like receptor, MAPK mitogen-activated protein kinases, JNK jun N-terminal kinase, ERK extracellular signal-regulated kinase, iNOS Inducible nitric oxide synthase, IL-1ß interleukin-1ß, IL-6 interleukin-6, BDNF brain-derived neurotrophic factor, GABA γ-Aminobutyric acid, GABAR γ-Aminobutyric acid receptor, NMDAR N-methyl-D-aspartate receptor, AMPAR α-amino-3-hydroxy-5-methyl-4-isoxazolepropi-onic acid receptor, IL-4 interleukin-4, IL-13 interleukin-13, IL-10 interleukin-10, Arg-1 Arginase 1, FGF fibroblast growth factor, GDNF glial cell-derived neurotrophic factor, IGF-1 insulin-like growth factor-1, NGF nerve growth factor, CD Cluster of differentiation.
Assuntos
Fator Estimulador de Colônias de Macrófagos , Microglia , Humanos , Microglia/metabolismo , Fator Estimulador de Colônias de Macrófagos/metabolismo , Doenças Neuroinflamatórias , Ligantes , Dor/metabolismo , Hiperalgesia/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos , Fator de Necrose Tumoral alfa/metabolismoRESUMO
BACKGROUND AND AIM: Huntington's disease (HD) is a rare inherited disease portrayed with marked cognitive and motor decline owing to extensive neurodegeneration. NADPH oxidase is considered as an important contributor to the oxidative injury in several neurodegenerative disorders including HD. Thus, the present study explored the possible neuroprotective effects of diapocynin, a specific NADPH oxidase inhibitor, against 3-nitropropionic acid (3-NP) model of HD in rats. METHODS: Animals received diapocynin (10 mg/kg/day, p.o), 30 min before 3-NP (10 mg/kg/day, i.p) over a period of 14 days. RESULTS: Diapocynin administration attenuated 3-NP-induced oxidative stress with significant increase in reduced glutathione, glutathione-S-transferase, nuclear factor erythroid 2-related factor 2, and brain-derived neurotrophic factor striatal contents contrary to NADPH oxidase (NOX2; gp91phox subunit) diminished expression. Moreover, diapocynin mitigated 3-NP-associated neuroinflammation and glial activation with prominent downregulation of nuclear factor-Ðß p65 and marked decrement of inducible nitric oxide synthase content in addition to decreased immunoreactivity of ionized calcium binding adaptor molecule 1 and glial fibrillary acidic protein; markers of microglial and astroglial activation, respectively. Treatment with diapocynin hindered 3-NP-induced apoptosis with prominent decrease in tumor suppressor protein and Bcl-2-associated X protein contents whereas the anti-apoptotic marker; B-cell lymphoma-2 content was noticeably increased. Diapocynin neuroprotective effects could be attributed to silent information regulator 1 upregulation which curbed 3-NP-associated hazards resulting in improved motor functions witnessed during open field, rotarod, and grip strength tests as well as attenuated 3-NP-associated histopathological derangements. CONCLUSION: The present findings indicated that diapocynin could serve as an auspicious nominee for HD management.
Assuntos
Doença de Huntington , Fármacos Neuroprotetores , Acetofenonas , Animais , Compostos de Bifenilo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Cálcio/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Glutationa/metabolismo , Doença de Huntington/induzido quimicamente , Doença de Huntington/tratamento farmacológico , NADPH Oxidases/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/farmacologia , Óxido Nítrico Sintase Tipo II/metabolismo , Nitrocompostos , Propionatos , Ratos , Transdução de Sinais , Sirtuína 1/metabolismo , Transferases/metabolismo , Transferases/farmacologia , Proteínas Supressoras de Tumor/efeitos adversos , Proteínas Supressoras de Tumor/metabolismo , Proteína X Associada a bcl-2/metabolismoRESUMO
Autophagy and mitochondrial deficits are characteristics of early phase of Alzheimer's disease (AD). Sodium-glucose cotransporter-2 inhibitors have been nominated as a promising class against AD hallmarks. However, there are no available data yet to discuss the impact of gliflozins on autophagic pathways in AD. Peripherally, dapagliflozin's (DAPA) effect is mostly owed to autophagic signals. Thus, the goal of this study is to screen the power of DAPA centrally on LKB1/AMPK/SIRT1/mTOR signaling in the ovariectomized/D-galactose (OVX/D-Gal) rat model. Animals were arbitrarily distributed between 5 groups; the first group undergone sham operation, while remaining groups undergone OVX followed by D-Gal (150 mg/kg/day; i.p.) for 70 days. After 6 weeks, the third, fourth, and fifth groups received DAPA (1 mg/kg/day; p.o.); concomitantly with the AMPK inhibitor dorsomorphin (DORSO, 25 µg/rat, i.v.) in the fourth group and the SIRT1 inhibitor EX-527 (10 µg/rat, i.v.) in the fifth group. DAPA mitigated cognitive deficits of OVX/D-Gal rats, as mirrored in neurobehavioral task with hippocampal histopathological examination and immunohistochemical aggregates of p-Tau. The neuroprotective effect of DAPA was manifested by elevation of energy sensors; AMP/ATP ratio and LKB1/AMPK protein expressions along with autophagic markers; SIRT1, Beclin1, and LC3B expressions. Downstream the latter, DAPA boosted mTOR and mitochondrial function; TFAM, in contrary lessened BACE1. Herein, DORSO or EX-527 co-administration prohibited DAPA's actions where DORSO elucidated DAPA's direct effect on LKB1 while EX-527 mirrored its indirect effect on SIRT1. Therefore, DAPA implied its anti-AD effect, at least in part, via boosting hippocampal LKB1/AMPK/SIRT1/mTOR signaling in OVX/D-Gal rat model.
Assuntos
Doença de Alzheimer , Inibidores do Transportador 2 de Sódio-Glicose , Animais , Ratos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Proteínas Quinases Ativadas por AMP/metabolismo , Secretases da Proteína Precursora do Amiloide/farmacologia , Ácido Aspártico Endopeptidases/farmacologia , Autofagia , Galactose/farmacologia , Sirtuína 1/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Serina-Treonina Quinases TORRESUMO
NADPH oxidase (NOX) has been identified as a crucial contender of oxidative damage in Alzheimer's disease (AD). However, the capability of diapocynin, a NOX inhibitor, to offer neuroprotection in AD models is still a matter of debate. Hence, the current work is dedicated to investigate the influence of diapocynin on cognitive impairment prompted by ovariectomy combined with D-galactose injection in rats (an AD animal model), and to elucidate the signaling mechanisms regulating diapocynin-induced effects. Female rats were exposed to ovariectomy or sham operation. Ovariectomized rats were injected intraperitoneally with D-galactose (150 mg/kg/day) for 70 days and, on day 43, they were orally treated with diapocynin (10 mg/kg/day) for 28 days. Diapocynin amended cognitive functions as confirmed using novel object recognition and Morris water maze tests along with histopathological improvement. It caused a prominent decrement in ß-secretase, p-tau, and amyloid ß, contrary to α-secretase elevation in hippocampus and hampered neuroinflammation and oxidative stress, manifested by declined levels of NOX1, tumor necrosis factor-α, and nuclear factor-kappa B p65. In addition, diapocynin augmented synaptophysin, brain-derived neurotrophic factor, and phospho-cAMP response element binding protein and enhanced protein expression of phosphorylated forms of phosphoinositide 3-kinase (PI3K), glycogen synthase kinase-3ß (GSK-3ß), protein kinase B (Akt), extracellular signal-regulated kinase (ERK) 1/2, ERK kinase kinase (Raf-1), and ERK kinase (MEK) 1/2, while inhibiting those of c-Jun and c-Jun N-terminal kinase (JNK). In conclusion, diapocynin attenuated memory impairment and AD-like anomalies via activating Raf-1/MEK/ERK and PI3K/Akt/GSK-3ß, while inhibiting JNK/c-Jun signaling cascades.
Assuntos
Acetofenonas/farmacologia , Doença de Alzheimer/tratamento farmacológico , Compostos de Bifenilo/farmacologia , Cognição/efeitos dos fármacos , Galactose/metabolismo , Nootrópicos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Doença de Alzheimer/metabolismo , Animais , Feminino , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Memória/efeitos dos fármacos , Ratos , Ratos WistarRESUMO
BACKGROUND: Status epilepticus (SE) as a severe neurodegenerative disease, greatly negatively affects people's health, and there is an urgent need for innovative treatments. The valuable neuroprotective effects of glucagon-like peptide-1 (GLP-1) in several neurodegenerative diseases have raised motivation to investigate the dipeptidyl peptidase-4 (DPP-4) inhibitor; alogliptin (ALO), an oral antidiabetic drug as a potential treatment for SE. ALO has shown promising neuroprotective effects in Alzheimer's and Parkinson's diseases, but its impact on SE has not yet been studied. AIM: The present study aimed to explore the repurposing potential for ALO in a lithium/pilocarpine (Li/Pil)-induced SE model in rats. MAIN METHODS: ALO (30 mg/kg/day) was administered via gavage for 14 days, and SE was subsequently induced in the rats using a single dose of Li/Pil (127/60 mg/kg), while levetiracetam was used as a standard antiepileptic drug. KEY FINDINGS: The results showed that ALO reduced seizure severity and associated hippocampal neurodegeneration. ALO also increased γ-aminobutyric acid (GABA) levels, diminished glutamate spikes, and corrected glial fibrillary acidic protein (GFAP) changes. At the molecular level, ALO increased GLP-1 levels and activated its downstream signaling pathway, AMP-activated protein kinase (AMPK)/sirtuin-1 (SIRT1). ALO also dampened the brain's pro-oxidant response, curbed neuroinflammation, and counteracted hippocampal apoptosis affording neuroprotection. In addition, it activated autophagy as indicated by Beclin1 elevation. SIGNIFICANCE: This study suggested that the neuroprotective properties and autophagy-enhancing effects of ALO make it a promising treatment for SE and can potentially be used as a management approach for this condition.
Assuntos
Autofagia , Fator 2 Relacionado a NF-E2 , Fármacos Neuroprotetores , Pilocarpina , Piperidinas , Convulsões , Sirtuína 1 , Animais , Ratos , Sirtuína 1/metabolismo , Fármacos Neuroprotetores/farmacologia , Masculino , Autofagia/efeitos dos fármacos , Piperidinas/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Convulsões/metabolismo , Lítio/farmacologia , Proteínas Quinases Ativadas por AMP/metabolismo , Uracila/análogos & derivados , Uracila/farmacologia , Ratos Sprague-Dawley , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/patologia , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/tratamento farmacológico , Estado Epiléptico/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
RATIONALE: Major depression has been an area of extensive research during the last decades, for it represents a leading cause of disability and suicide. The stark rise of depression rates influenced by life stressors, economic threats, pandemic era, and resistance to classical treatments, has made the disorder rather challenging. Adult hippocampal neurogenesis and plasticity are particularly sensitive to the dynamic interplay between autophagy and inflammation. In fact, the intricate balance between the two processes contributes to neuronal homeostasis and survival. OBJECTIVES: Having demonstrated promising potentials in AMPK activation, a major metabolic sensor and autophagy regulator, empagliflozin (Empa) was investigated for possible antidepressant properties in the reserpine rat model of depression. RESULTS: While the reserpine protocol elicited behavioral, biochemical, and histopathological changes relevant to depression, Empa outstandingly hindered these pathological perturbations. Importantly, hippocampal autophagic response markedly declined with reserpine which disrupted the AMPK/mTOR/Beclin1/LC3B machinery and, conversely, neuro-inflammation prevailed under the influence of the NLRP3 inflammasome together with oxidative/nitrative stress. Consequently, AMPK-mediated neurotrophins secretion obviously deteriorated through PKCζ/NF-κB/BDNF/CREB signal restriction. Empa restored hippocampal monoamines and autophagy/inflammation balance, driven by AMPK activation. By promoting the atypical PKCζ phosphorylation (Thr403) which subsequently phosphorylates NF-κB at Ser311, AMPK successfully reinforced BDNF/CREB signal and hippocampal neuroplasticity. The latter finding was supported by hippocampal CA3 toluidine blue staining to reveal intact neurons. CONCLUSION: The current study highlights an interesting role for Empa as a regulator of autophagic and inflammatory responses in the pathology of depression. The study also pinpoints an unusual contribution for NF-κB in neurotrophins secretion via AMPK/PKCζ/NF-κB/BDNF/CREB signal transduction. Accordingly, Empa can have special benefits in diabetic patients with depressive symptoms. LIMITATIONS: The influence of p-NF-κB (Ser311) on NLRP3 inflammasome assembly and activation has not been investigated, which can represent an interesting point for further research.
RESUMO
Fibromyalgia (FM) is a pain disorder marked by generalized musculoskeletal pain accompanied by depression, fatigue, and sleep disturbances. Galantamine (Gal) is a positive allosteric modulator of neuronal nicotinic acetylcholine receptors (nAChRs) and a reversible inhibitor of cholinesterase. The current study aimed to explore the therapeutic potential of Gal against reserpine (Res)-induced FM-like condition along with investigating the α7-nAChR's role in Gal-mediated effects. Rats were injected with Res (1 mg/kg/day; sc) for 3 successive days then Gal (5 mg/kg/day; ip) was given alone and with the α7-nAChR blocker methyllycaconitine (3 mg/kg/day; ip), for the subsequent 5 days. Galantamine alleviated Res-induced histopathological changes and monoamines depletion in rats' spinal cord. It also exerted analgesic effect along with ameliorating Res-induced depression and motor-incoordination as confirmed by behavioral tests. Moreover, Gal produced anti-inflammatory effect through modulating AKT1/AKT2 and shifting M1/M2 macrophage polarization. The neuroprotective effects of Gal were mediated through activating cAMP/PKA and PI3K/AKT pathways in α7-nAChR-dependent manner. Thus, Gal can ameliorate Res-induced FM-like symptoms and mitigate the associated monoamines depletion, neuroinflammation, oxidative stress, apoptosis, and neurodegeneration through α7-nAChR stimulation, with the involvement of cAMP/PKA, PI3K/AKT, and M1/M2 macrophage polarization.
Assuntos
Fibromialgia , Galantamina , Ratos , Animais , Galantamina/farmacologia , Galantamina/uso terapêutico , Reserpina/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Microglia , Fibromialgia/induzido quimicamente , Fibromialgia/tratamento farmacológicoRESUMO
Neuroinflammation mediated by microglia activation is a critical contributor to Alzheimer's disease (AD) pathogenesis. Dysregulated microglia polarization in terms of M1 overactivation with M2 inhibition is involved in AD pathological damage. Scoparone (SCO), a coumarin derivative, displays several beneficial pharmacological effects including anti-inflammatory and anti-apoptotic properties, however, its neurological effect in AD is still elusive. This study investigated the neuroprotective potential of SCO in AD animal model focusing on determining its effect on M1/M2 microglia polarization and exploring the plausible mechanism involved via investigating its modulatory role on TLR4/MyD88/NF-κB and NLRP3 inflammasome. Sixty female Wistar rats were randomly allocated into four groups. Two groups were sham-operated and treated or untreated with SCO, and the other two groups were subjected to bilateral ovariectomy (OVX) and received D-galactose (D-Gal; 150 mg/kg/day, i.p) alone or with SCO (12.5 mg/kg/day, i.p) for 6 weeks. SCO improved memory functions of OVX/D-Gal rats in the Morris water maze and novel object recognition tests. It also reduced the hippocampal burden of amyloid-ß42 and p-Tau, additionally, the hippocampal histopathological architecture was prominently preserved. SCO inhibited the gene expression of TLR4, MyD88, TRAF-6, and TAK-1, additionally, p-JNK and NF-κBp65 levels were significantly curbed. This was associated with repression of NLRP3 inflammasome along with M1-to-M2 microglia polarization shifting as exemplified by mitigating pro-inflammatory M1 marker (CD86) and elevating M2 neuroprotective marker (CD163). Therefore, SCO could promote microglia transition towards M2 through switching off TLR4/MyD88/TRAF-6/TAK-1/NF-κB axis and inhibiting NLRP3 pathway, with consequent mitigation of neuroinflammation and neurodegeneration in OVX/D-Gal AD model.
Assuntos
Doença de Alzheimer , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Feminino , Humanos , Ratos , Doença de Alzheimer/metabolismo , Cumarínicos/farmacologia , Galactose/metabolismo , Inflamassomos/metabolismo , Microglia , Fator 88 de Diferenciação Mieloide/metabolismo , Doenças Neuroinflamatórias , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ovariectomia , Ratos Wistar , Transdução de Sinais , Receptor 4 Toll-Like/metabolismoRESUMO
Depression is a serious mood disorder characterized by monoamines deficiency, oxidative stress, neuroinflammation, and cell death. Niacin (vitamin B3 or nicotinic acid, NA), a chief mediator of neuronal development and survival in the central nervous system, exerts neuroprotective effects in several experimental models. AIMS: This study aimed to investigate the effect of NA in lipopolysaccharide (LPS) mouse model of depression exploring its ability to regulate sirtuin1/poly (ADP-ribose) polymerase-1 (PARP-1)/nod-likereceptor protein 3 (NLRP3) signaling. MAIN METHODS: Mice were injected with LPS (500 µg/kg, i.p) every other day alone or concurrently with oral doses of either NA (40 mg/kg/day) or escitalopram (10 mg/kg/day) for 14 days. KEY FINDINGS: Administration of NA resulted in significant attenuation of animals' despair reflected by decreased immobility time in forced swimming test. Moreover, NA induced monoamines upsurge in addition to sirtuin1 activation with subsequent down regulation of PARP-1 in the hippocampus. Further, it diminished nuclear factor-κB (NF-κB) levels and inhibited NLRP3 inflammasome with consequent reduction of caspase-1, interleukin-1ß and tumor necrosis factor-α levels, thus mitigating LPS-induced neuroinflammation. NA also reduced tumor suppressor protein (p53) while elevating brain-derived neurotrophic factor levels. LPS-induced decline in neuronal survival was reversed by NA administration with an obvious increase in the number of intact cells recorded in the histopathological micrographs. SIGNIFICANCE: Accordingly, NA is deemed as a prosperous candidate for depression management via targeting SIRT1/PARP-1 pathway.
Assuntos
Fármacos Neuroprotetores , Niacina , Animais , Camundongos , Depressão/induzido quimicamente , Depressão/tratamento farmacológico , Depressão/metabolismo , Inflamassomos/metabolismo , Lipopolissacarídeos/efeitos adversos , Doenças Neuroinflamatórias , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Poli(ADP-Ribose) Polimerase-1 , Inibidores de Poli(ADP-Ribose) Polimerases , Sirtuína 1/metabolismoRESUMO
Huntington's disease (HD) is an inherited devastating neurodegenerative disorder with disabling motor and cognitive derangements that hinder the patients from performing their daily activities. AIMS: The present study was carried out to investigate telmisartan-induced neuroprotection against 3-nitropropionic acid (3-NP) model of HD in rats. MAIN METHODS: Telmisartan was administered orally with a dose of 10 mg/kg/day, 1 h prior to 3-NP (10 mg/kg/day, i.p) for 14 days. KEY FINDINGS: 3-NP-injected animals which were treated with telmisartan showed marked improvement in muscle strength and motor functions evaluated by rotarod, grip strength, and open field tests. Moreover, administration of telmisartan attenuated 3-NP-induced oxidative stress, neuro-inflammation, and apoptosis with prominent decline in malondialdehyde striatal content in addition to NADPH oxidase reduced expression contrary to noticeable increment in reduced glutathione content. Additionally, the pro-inflammatory markers; tumor necrosis factor-α, interleukin-1ß, prostaglandin E2, and cyclooxygenase-2 contents were significantly reduced along with decreased active caspase-3 immunoreactivity. Telmisartan was also implicated in the modulation of phosphatidyl inositol 3-kinase/protein kinase B/glycogen synthase kinase-3ß (PI3K/Akt/GSK-3ß) and extracellular signal-regulated kinase (ERK) 1/2 cascades with consequent anti-oxidative, anti-inflammatory, and anti-apoptotic effects. Photomicrographs of telmisartan-treated animals confirmed its neuroprotective effects showing dismounted neuronal death and obvious increase in neuronal survival. These beneficial effects could be attributed to telmisartan's ability to induce peroxisome proliferator activated receptor-γ expression as well as its well-known blocking effect of angiotensin-II receptors type 1. SIGNIFICANCE: Subsequently, telmisartan is deemed as a promising candidate for HD management.
Assuntos
Doença de Huntington , Fármacos Neuroprotetores , Animais , Glicogênio Sintase Quinase 3 beta , Humanos , Doença de Huntington/induzido quimicamente , Doença de Huntington/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Nitrocompostos , PPAR gama , Fosfatidilinositol 3-Quinases/metabolismo , Propionatos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Telmisartan/farmacologiaRESUMO
Anxiety is a neuropsychiatric disturbance that is commonly manifested in various dementia forms involving Alzheimer's disease (AD). The mechanisms underlying AD-associated anxiety haven't clearly recognized the role of energy metabolism in anxiety represented by the amygdala's autophagic sensors; liver kinase B1 (LKB1)/adenosine monophosphate kinase (AMPK). Dapagliflozin (DAPA), a SGLT2 inhibitor, acts as an autophagic activator through LKB1 activation in several diseases including AD. Herein, the propitious yet undetected anxiolytic potential of DAPA as an autophagic enhancer was investigated in AD animal model with emphasis on amygdala's GABAergic neurotransmission and brain-derived neurotrophic factor (BDNF). Alzheimer's disease was induced by ovariectomy (OVX) along with seventy-days-D-galactose (D-Gal) administration (150 mg/kg/day, i.p). On the 43rd day of D-Gal injection, OVX/D-Gal-subjected rats received DAPA (1 mg/kg/day, p.o) alone or with dorsomorphin the AMPK inhibitor (DORSO, 25 µg/rat, i.v.). In the amygdala, LKB1/AMPK were activated by DAPA inducing GABAB2 receptor stimulation; an effect that was abrogated by DORSO. Dapagliflozin also replenished the amygdala GABA, NE, and 5-HT levels along with glutamate suppression. Moreover, DAPA triggered BDNF production with consequent activation of its receptor, TrkB through activating GABAB2-related downstream phospholipase C/diacylglycerol/protein kinase C (PLC/DAG/PKC) signaling. This may promote GABAA expression, verifying the crosstalk between GABAA and GABAB2. The DAPA's anxiolytic effect was visualized by improved behavioral traits in elevated plus maze together with amendment of amygdala' histopathological abnormalities. Thus, the present study highlighted DAPA's anxiolytic effect which was attributed to GABAB2 activation and its function to induce BDNF/TrkB and GABAA expression through PLC/DAG/PKC pathway in AMPK-dependent manner.
Assuntos
Doença de Alzheimer , Ansiolíticos , Feminino , Animais , Ratos , Fator Neurotrófico Derivado do Encéfalo , Proteínas Quinases Ativadas por AMP/metabolismo , Monofosfato de Adenosina , Ansiedade/tratamento farmacológico , Ácido gama-AminobutíricoRESUMO
Dysregulated inflammatory responses and blood-brain barrier (BBB) dysfunction are recognized as central factors in the development of psychiatric disorders. The present study was designed to evaluate the effect of niacin on BBB integrity in ketamine-induced model of psychosis. Meanwhile, mepenzolate bromide (MPN), a GPR109A receptor blocker, was used to investigate the role of this receptor on the observed niacin's effect. Male Wistar rats received ketamine (30 mg/kg/day, i.p) for 5 consecutive days and then niacin (40 mg/kg/day, p.o), with or without MPN (5 mg/kg/day, i.p), was given for the subsequent 15 days. Three days before the end of experiment, rats were behaviorally tested using open field, novel object recognition, social interaction, and forced swimming tests. Niacin significantly ameliorated ketamine-induced behavioral deficits, amended gamma aminobutyric acid and glutamate concentration, decreased tumor necrosis factor-α and matrix metallopeptidase 9 levels, and increased netrin-1 contents in the hippocampus of rats. Niacin also augmented the hippocampal expression of ZO-1, occludin, and claudin-5 proteins, indicating the ability of niacin to restore the BBB integrity. Moreover, the histopathologic changes in hippocampal neurons were alleviated. Since all the beneficial effects of niacin in the present investigation were partially abolished by the co-administration of MPN; GPR109A receptor was proven to partially mediate the observed antipsychotic effects of niacin. These data revealed that GPR109A-mediated signaling pathways might represent potential targets for therapeutic interventions to prevent or slow the progression of psychosis.
Assuntos
Barreira Hematoencefálica , Encefalite , Hipolipemiantes , Niacina , Transtornos Psicóticos , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Modelos Animais de Doenças , Encefalite/induzido quimicamente , Encefalite/tratamento farmacológico , Hipolipemiantes/farmacologia , Hipolipemiantes/uso terapêutico , Ketamina/farmacologia , Masculino , Niacina/farmacologia , Niacina/uso terapêutico , Transtornos Psicóticos/tratamento farmacológico , Ratos , Ratos Wistar , Receptores Acoplados a Proteínas G/metabolismo , Receptores Nicotínicos/metabolismo , Proteínas de Junções Íntimas/metabolismoRESUMO
OBJECTIVES: Reduced male fertility is highly prevalent with hypercholesterolaemia. Though statins are drugs of choice for hypercholesterolaemia, their effect on male fertility is still controversial and dose-dependent. Grape seed extract (GSE) possess hypocholesterolemic and testicular protective effects. Thus, this study aimed to investigate the effects of low-dose atorvastatin (ATV) on male infertility in hypercholesterolaemic rats and assess the additional value of combining ATV with GSE. METHODS: Male rats were randomized into four groups. The normal group was fed a standard diet. The remaining groups were fed a high-fat diet (HFD) for 1 month to induce hypercholesterolaemia. Two HFD groups were administered either ATV (1 mg/kg) alone or combined with GSE (200 mg/kg) orally for 65 days, while the third group served as HFD control. KEY FINDINGS: Treatment with ATV or ATV/GSE attenuated dyslipidemia-induced alteration in serum HDL-cholesterol, LDL-cholesterol, and total cholesterol. ATV enhanced serum testosterone, sperm count and motility and fertility index. The effect on testosterone and sperm count was more pronounced by ATV/GSE. Moreover, ATV reduced testicular malondialdehyde, nitric oxide, caspase-9 and caspase-3 while elevated reduced glutathione and superoxide dismutase along with catalase activity. Noteworthy, GSE/ATV induced more powerful antioxidant and anti-apoptotic effects. CONCLUSION: GSE enhanced ATV's protective effect against hypercholesterolaemia-induced infertility via antioxidant and anti-apoptotic mechanisms.
Assuntos
Atorvastatina/farmacologia , Extrato de Sementes de Uva/farmacologia , Hipercolesterolemia/complicações , Infertilidade Masculina/prevenção & controle , Animais , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/farmacologia , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Atorvastatina/administração & dosagem , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Quimioterapia Combinada , Extrato de Sementes de Uva/administração & dosagem , Hipercolesterolemia/tratamento farmacológico , Infertilidade Masculina/etiologia , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Testículo/efeitos dos fármacos , Testículo/patologiaRESUMO
Though selective serotonin reuptake inhibitors (SSRIs) have been found to increase cognitive performance in some studies on patients and animal models of Alzheimer's disease (AD), other studies have reported contradictory results, and the mechanism of action has not been fully described. This study aimed to examine the effect of escitalopram, an SSRI, in an experimental model of AD and to determine the involved intracellular signalling pathways. Ovariectomized rats were administered D-galactose (150 mg/kg/day, i.p) over ten weeks to induce AD. Treatment with escitalopram (10 mg/kg/day, p.o) for four weeks, starting from the 7th week of D-galactose injection, enhanced memory performance and attenuated associated histopathological changes. Escitalopram reduced hippocampal amyloid ß 42, ß-secretase, and p-tau, while increasing α-secretase levels. Furthermore, it decreased tumor necrosis factor-α, nuclear factor-kappa B p65, and NADPH oxidase, while enhancing brain-derived neurotrophic factor, phospho-cAMP response element binding protein, and synaptophysin levels. Moreover, escitalopram diminished the protein expression of the phosphorylated forms of c-Jun N-terminal kinase (JNK)/c-Jun, while increasing those of phosphoinositide 3-kinase (PI3K), protein kinase B (Akt), glycogen synthase kinase-3ß (GSK-3ß), extracellular signal-regulated kinase (ERK) and its upstream kinases MEK and Raf-1. In conclusion, escitalopram ameliorated D-galactose/ovariectomy-induced AD-like features through modulation of PI3K/Akt/GSK-3ß, Raf-1/MEK/ERK, and JNK/c-Jun pathways.
Assuntos
Antidepressivos de Segunda Geração/uso terapêutico , Citalopram/uso terapêutico , Disfunção Cognitiva/tratamento farmacológico , Aprendizagem/efeitos dos fármacos , Memória/efeitos dos fármacos , Animais , Feminino , Galactose/administração & dosagem , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , MAP Quinase Quinase 4/metabolismo , Sistema de Sinalização das MAP Quinases , Ovariectomia , Ratos , Ratos WistarRESUMO
The prevalence or recurrence of depression is seriously increased in women during the transition to and after menopause. The chronic hypo-estrogenic state of menopause may reduce the response to antidepressants; however the influence of estrogen therapy on their efficacy is still controversial. This study aimed at investigating the effects of combining escitalopram with 17ß-estradiol on depression and cognitive impairment induced by ovariectomy, an experimental model of human menopause. Young adult female Wistar rats were subjected to either sham operation or ovariectomy. Ovariectomized animals were treated chronically with escitalopram (10mg/kg/day, i.p) alone or with four doses of 17ß-estradiol (40µg/kg, s.c) given prior to the behavioral tests. Co-administration of 17ß-estradiol improved escitalopram-induced antidepressant effect in forced swimming test verified as more prominent decrease in the immobility time without opposing its memory enhancing effect in Morris water maze. 17ß-estradiol augmented the modulatory effects of escitalopram on the hippocampal levels of brain-derived neurotrophic factor and serotonin reuptake transporter as well as tumor necrosis factor-alpha without altering its effects on the gene expressions of serotonin receptor 1A, estrogen receptors alpha and beta, or acetylcholinestearase content. This combined therapy afforded synergistic protective effects on the brain histopathological architecture, particularly, the hippocampus. The antidepressant effect of 17ß-estradiol was abolished by pretreatment with estrogen receptor antagonist, tamoxifen (10mg/kg, p.o). In conclusion, 17ß-estradiol-induced antidepressant effect was confined to intracellular estrogen receptors activation. Moreover, 17ß-estradiol enhanced escitalopram's efficiency in ameliorating menopausal-like depression, via exerting synergistic neuroprotective and serotonin reuptake transporter modulatory effects, without impeding escitalopram-mediated cognitive improvement.