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1.
Adv Sci (Weinh) ; 11(29): e2308325, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38790144

RESUMO

Macrophages play pivotal roles in the regulation of inflammatory responses and tissue repair, making them a prime target for inflammation alleviation. However, the accurate and efficient macrophages targeting is still a challenging task. Motivated by the efficient and specific removal of apoptotic cells by macrophages efferocytosis, a novel biomimetic liposomal system called Effero-RLP (Efferocytosis-mediated Red blood cell hybrid Liposomes) is developed which incorporates the membrane of apoptotic red blood cells (RBCs) with liposomes for the purpose of highly efficient macrophages targeting. Rosiglitazone (ROSI), a PPARγ agonist known to attenuate macrophage inflammatory responses, is encapsulated into Effero-RLP as model drug to regulate macrophage functions in DSS-induced colitis mouse model. Intriguingly, the Effero-RLP exhibits selective and efficient uptake by macrophages, which is significantly inhibited by the efferocytosis blocker Annexin V. In animal models, the Effero-RLP demonstrates rapid recognition by macrophages, leading to enhanced accumulation at inflammatory sites. Furthermore, ROSI-loaded Effero-RLP effectively alleviates inflammation and protects colon tissue from injury in the colitis mouse model, which is abolished by deletion of macrophages from mice model. In conclusion, the study highlights the potential of macrophage targeting using efferocytosis biomimetic liposomes. The development of Effero-RLP presents novel and promising strategies for alleviating inflammation.


Assuntos
Sistemas de Liberação de Medicamentos , Inflamação , Lipossomos , Macrófagos , Animais , Camundongos , Biomimética/métodos , Colite/tratamento farmacológico , Colite/metabolismo , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos/métodos , Eferocitose/efeitos dos fármacos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Rosiglitazona/farmacologia
2.
Int J Biol Sci ; 20(2): 751-764, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38169614

RESUMO

Autophagy is a highly conserved physiological process that maintains cellular homeostasis by recycling cellular contents. Selective autophagy is based on the specificity of cargo recognition and has been implicated in various human diseases, including neurodegenerative diseases and cancer. Selective autophagy receptors and modulators play key roles in this process. Identifying these receptors and modulators and their roles is critical for understanding the machinery and physiological function of selective autophagy and providing therapeutic value for diseases. Using modern researching tools and novel screening technologies, an increasing number of selective autophagy receptors and modulators have been identified. A variety of Strategies and approaches, including protein-protein interactions (PPIs)-based identification and genome-wide screening, have been used to identify selective autophagy receptors and modulators. Understanding the strengths and challenges of these approaches not only promotes the discovery of even more such receptors and modulators but also provides a useful reference for the identification of regulatory proteins or genes involved in other cellular mechanisms. In this review, we summarize the functions, disease association, and identification strategies of selective autophagy receptors and modulators.


Assuntos
Autofagia , Humanos , Autofagia/genética , Homeostase
3.
Zool Res ; 44(6): 1132-1145, 2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-37963840

RESUMO

Alzheimer's disease (AD) is an age-related progressive neurodegenerative disorder that leads to cognitive impairment and memory loss. Emerging evidence suggests that autophagy plays an important role in the pathogenesis of AD through the regulation of amyloid-beta (Aß) and tau metabolism, and that autophagy dysfunction exacerbates amyloidosis and tau pathology. Therefore, targeting autophagy may be an effective approach for the treatment of AD. Animal models are considered useful tools for investigating the pathogenic mechanisms and therapeutic strategies of diseases. This review aims to summarize the pathological alterations in autophagy in representative AD animal models and to present recent studies on newly discovered autophagy-stimulating interventions in animal AD models. Finally, the opportunities, difficulties, and future directions of autophagy targeting in AD therapy are discussed.


Assuntos
Doença de Alzheimer , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/veterinária , Peptídeos beta-Amiloides , Autofagia/fisiologia , Modelos Animais
4.
EMBO Mol Med ; 15(12): e17815, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-37994307

RESUMO

Efficient clearance of dying cells (efferocytosis) is an evolutionarily conserved process for tissue homeostasis. Genetic enhancement of efferocytosis exhibits therapeutic potential for inflammation resolution and tissue repair. However, pharmacological approaches to enhance efferocytosis remain sparse due to a lack of targets for modulation. Here, we report the identification of columbamine (COL) which enhances macrophage-mediated efferocytosis and attenuates intestinal inflammation in a murine colitis model. COL enhances efferocytosis by promoting LC3-associated phagocytosis (LAP), a non-canonical form of autophagy. Transcriptome analysis and pharmacological characterization revealed that COL is a biased agonist that occupies a part of the ligand binding pocket of formyl peptide receptor 2 (FPR2), a G-protein coupled receptor involved in inflammation regulation. Genetic ablation of the Fpr2 gene or treatment with an FPR2 antagonist abolishes COL-induced efferocytosis, anti-colitis activity and LAP. Taken together, our study identifies FPR2 as a potential target for modulating LC3-associated efferocytosis to alleviate intestinal inflammation and highlights the therapeutic value of COL, a natural and biased agonist of FPR2, in the treatment of inflammatory bowel disease.


Assuntos
Colite , Camundongos , Animais , Fagocitose , Transdução de Sinais , Inflamação/genética , Macrófagos/metabolismo , Colite/metabolismo
5.
Cancer Lett ; 573: 216364, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37648148

RESUMO

Isocitrate dehydrogenase (IDH) 1 and 2, as essential enzymes in energy metabolism, contribute to the survival and drug resistance of a variety of solid tumors, especially for colorectal cancer (CRC). However, the underlying molecular mechanism still remains unclear. In this study, IDH1 was identified as a crucial cellular target of a natural-derived anti-CRC small molecule lycorine, using the unbiased thermal proteome profiling (TPP) strategy. We found that lycorine directly targeted a unique C-terminal domain of IDH1, and disrupted IDH1 interaction with deacetylase sirtuin 1 (SIRT1), thereby significantly promoting IDH1 acetylation modification. Then, lycorine noticeably triggered oxidative stress in CRC cells to cause mitochondrial membranes injury, and subsequently facilitated mitochondrial fission. Specific knockdown of IDH1 or SIRT1 markedly aggrieved lycorine-mediated oxidative stress and mitochondrial fragmentation in CRC cells. Furthermore, the combination of lycorine and sirtuins blocker nicotinamide (NAM) exhibited a synergic therapeutic effect in CRC cells. Collectively, our results reveal that IDH1 may serve as a promising therapeutic target for CRC via pharmacologically driving oxidative stress-dependent mitochondrial dynamics imbalance.


Assuntos
Neoplasias Colorretais , Dinâmica Mitocondrial , Humanos , Acetilação , Sirtuína 1 , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Isocitrato Desidrogenase/genética
6.
Pharmacol Res ; 194: 106835, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37348691

RESUMO

Maintaining mitochondrial homeostasis is a potential therapeutic strategy for various diseases, including neurodegenerative diseases, cardiovascular diseases, metabolic disorders, and cancer. Selective degradation of mitochondria by autophagy (mitophagy) is a fundamental mitochondrial quality control mechanism conserved from yeast to humans. Indeed, small-molecule modulators of mitophagy are valuable pharmaceutical tools that can be used to dissect complex biological processes and turn them into potential drugs. In the past few years, pharmacological regulation of mitophagy has shown promising therapeutic efficacy in various disease models. However, with the increasing number of chemical mitophagy modulator studies, frequent methodological flaws can be observed, leading some studies to draw unreliable or misleading conclusions. This review attempts (a) to summarize the molecular mechanisms of mitophagy; (b) to propose a Mitophagy Modulator Characterization System (MMCS); (c) to perform a comprehensive analysis of methods used to characterize mitophagy modulators, covering publications over the past 20 years; (d) to provide novel targets for pharmacological intervention of mitophagy. We believe this review will provide a panorama of current research on chemical mitophagy modulators and promote the development of safe and robust mitophagy modulators with therapeutic potential by introducing high methodological standards.


Assuntos
Doenças Cardiovasculares , Neoplasias , Humanos , Mitofagia , Autofagia , Mitocôndrias/metabolismo , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo
7.
Oxid Med Cell Longev ; 2022: 1544244, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36065437

RESUMO

Alzheimer's disease (AD) is a progressive and irreversible neurodegenerative disorder for which there is no effective therapeutic strategy. PcActx peptide from the transcriptome of zoantharian Palythoa caribaeorum has recently been identified and verified as a novel antagonist of transient receptor potential cation channel subfamily V member 1 (TRPV1). In the present study, we further investigated the neuroprotective potential of PcActx peptide and its underlying mechanism of action, in an N2a/APP cell model of AD. Both Western blot and RT-PCR analysis revealed that PcActx peptide markedly inhibited the production of amyloid-related proteins and the expression of BACE1, PSEN1, and PSEN2. Moreover, PcActx peptide notably attenuated the capsaicin-stimulated calcium response and prevented the phosphorylation of CaMKII and CaMKIV (calcium-mediated proteins) in N2a/APP cells. Further investigation indicated that PcActx peptide significantly suppressed ROS generation through Nrf2 activation, followed by enhanced NQO1 and HO-1 levels. In addition, PcActx peptide remarkably improved Akt phosphorylation at Ser 473 (active) and Gsk3ß phosphorylation at Ser 9 (inactive), while pharmacological inhibition of the Akt/Gsk3ß pathway significantly attenuated PcActx-induced Nrf2 activation and amyloid downregulation. In conclusion, PcActx peptide functions as a TRPV1 modulator of intercellular calcium homeostasis, prevents AD-like amyloid neuropathology via Akt/Gsk3ß-mediated Nrf2 activation, and shows promise as an alternative therapeutic agent for AD.


Assuntos
Doença de Alzheimer , Fator 2 Relacionado a NF-E2 , Humanos , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Ácido Aspártico Endopeptidases/genética , Ácido Aspártico Endopeptidases/metabolismo , Cálcio/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Canais de Cátion TRPV
8.
Acta Pharm Sin B ; 12(3): 1240-1253, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35530150

RESUMO

The mammalian target of rapamycin (mTOR) pathway is abnormally activated in lung cancer. However, the anti-lung cancer effect of mTOR inhibitors as monotherapy is modest. Here, we identified that ginsenoside Rh2, an active component of Panax ginseng C. A. Mey., enhanced the anti-cancer effect of the mTOR inhibitor everolimus both in vitro and in vivo. Moreover, ginsenoside Rh2 alleviated the hepatic fat accumulation caused by everolimus in xenograft nude mice models. The combination of everolimus and ginsenoside Rh2 (labeled Eve-Rh2) induced caspase-independent cell death and cytoplasmic vacuolation in lung cancer cells, indicating that Eve-Rh2 prevented tumor progression by triggering paraptosis. Eve-Rh2 up-regulated the expression of c-MYC in cancer cells as well as tumor tissues. The increased c-MYC mediated the accumulation of tribbles homolog 3 (TRIB3)/P62+ aggresomes and consequently triggered paraptosis, bypassing the classical c-MYC/MAX pathway. Our study offers a potential effective and safe strategy for the treatment of lung cancer. Moreover, we have identified a new mechanism of TRIB3/P62+ aggresomes-triggered paraptosis and revealed a unique function of c-MYC.

9.
Int J Biol Sci ; 18(7): 2684-2702, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35541921

RESUMO

Macroautophagy/autophagy is the process of self-digestion through the lysosomes; it disassembles unnecessary or dysfunctional long-lived proteins and damaged organelles for the recycling of biomacromolecules. Unfortunately, cancer cells can hijack this mechanism to survive under metabolic stress or develop drug resistance during chemotherapy. Increasing evidence indicates that the combination of autophagy inhibition and chemotherapy is a promising cancer treatment strategy. However, effective autophagy inhibitors with satisfied potency, bioavailability, and clearly-defined drug targets are still rare. Here, we report the identification of a potent autophagy inhibitor toosendanin which can effectively block autophagosome maturation, causing the accumulation of autophagy substrates in multiple cancer cells. Toosendanin did not inhibit the fusion process between autophagosome and lysosome but elevated lysosomal pH and impaired lysosomal enzymes activity. Using rat liver lysosome fraction and purified yeast V-ATPase, we found that toosendanin directly inhibited V-ATPase activity. By applying cellular thermal shift assay (CETSA), immunoprecipitation-coupled LC-MS/MS analysis, and biotin-toosendanin pull-down assay, we confirmed the direct binding between toosendanin and V-ATPase. Furthermore, toosendanin blocked chemotherapy-induced protective autophagy in cultured cancer cells and xenograft tumor tissues to significantly enhance anti-cancer activity. These results suggest that toosendanin has the potential to be developed into an anti-cancer drug by blocking chemotherapy-induced protective autophagy.


Assuntos
Antineoplásicos , Neoplasias , ATPases Vacuolares Próton-Translocadoras , Adenosina Trifosfatases/metabolismo , Animais , Antineoplásicos/farmacologia , Autofagia , Cromatografia Líquida , Humanos , Neoplasias/tratamento farmacológico , Ratos , Espectrometria de Massas em Tandem , Triterpenos , ATPases Vacuolares Próton-Translocadoras/metabolismo , ATPases Vacuolares Próton-Translocadoras/farmacologia
10.
J Ovarian Res ; 15(1): 60, 2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35562770

RESUMO

OBJECTIVE: Women with an elevated basal FSH indicate diminished ovarian reserve and reduced oocyte and embryo numbers. DMSCs are likely to be involved in immune tolerance of pregnancy maintenance. We investigate the effect of follicle-stimulating hormones on the immunomodulatory functions of DMSCs. METHODS: DMSCs were primary cultured from decidual tissue. Pretreated DMSCs with mitomycin C, combined with CD4+ T lymphocytes, DMSCs + CD4+T co-culture system was established. Different physiological dose FSH (3 ng/ml,10 ng/ml,30 ng/ml,100 ng/ml) were used to co-culture system. Cytokines (IFN-γ, IL-2, IL-4, IL-6, IL-10, TNF-α) and other proteins (FSHR, MyD88) were measured. RESULTS: Compared with the control group (FSH (0 ng/mL) + CD4+T + DMSCs), the FSH concentration was 10, 30, and 100 ng/ml, IL-6 levels were significantly reduced (P < 0.05). IL-6, MyD88 protein expression was remarkably decreased (P < 0.05). CONCLUSION: FSH/FSHR could negatively regulate the immunosuppressive function of DMSCs by reducing secretion of IL-6 levels through MyD88 pathways, but upstream and downstream signalling pathways require further validation.


Assuntos
Interleucina-6 , Células-Tronco Mesenquimais , Feminino , Hormônio Foliculoestimulante/metabolismo , Hormônio Foliculoestimulante/farmacologia , Hormônio Foliculoestimulante Humano , Humanos , Interleucina-6/metabolismo , Células-Tronco Mesenquimais/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Gravidez
11.
Phytomedicine ; 101: 154125, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35525236

RESUMO

BACKGROUND: Parkinson's disease (PD) is a multi-factorial neurodegenerative disease affecting motor function of patients. The hall markers of PD are dopaminergic neuron loss in the midbrain and the presence of intra-neuronal inclusion bodies mainly composed of aggregation-prone protein alpha-synuclein (α-syn). Ubiquitin-proteasome system (UPS) is a multi-step reaction process responsible for more than 80% intracellular protein degradation. Impairment of UPS function has been observed in the brain tissue of PD patients. PDE4 inhibitors have been shown to activate cAMP-PKA pathway and promote UPS activity in Alzheimer's disease model. α-mangostin is a natural xanthonoid with broad biological activities, such as antioxidant, antimicrobial and antitumour activities. Structure-based optimizations based on α-mangostin produced a potent PDE4 inhibitor, 4e. Herein, we studied whether 4e could promote proteasomal degradation of α-syn in Parkinson's disease models through PKA activation. METHODS: cAMP Assay was conducted to quantify cAMP levels in samples. Model UPS substrates (Ub-G76V-GFP and Ub-R-GFP) were used to monitor UPS-dependent activity. Proteasome activity was investigated by short peptide substrate, Suc-LLVY-AMC, cleavage of which by the proteasome increases fluorescence sensitivity. Tet-on WT, A30P, and A53T α-syn-inducible PC12 cells and primary mouse cortical neurons from A53T transgenic mice were used to evaluate the effect of 4e against α-syn in vitro. Heterozygous A53T transgenic mice were employed to assess the effect of 4e on the clearance of α-syn in vivo, and further validations were applied by western blotting and immunohistochemistry. RESULTS: Taken together, α-mangostin derivative 4e, a PDE4 inhibitor, efficiently activated the cAMP/PKA pathway in neuronal cells, and promoted UPS activity as evidenced by enhanced degradation of UPS substrate Ub-G76V-GFP and Ub-R-GFP, as well as elevated proteasomal enzyme activity. Interestingly, 4e dramatically accelerated degradation of inducibly-expressed WT and mutant α-syn in PC12 cells, in a UPS dependent manner. Besides, 4e consistently activated PKA in primary neuron and A53T mice brain, restored UPS inhibition and alleviated α-syn accumulation in the A53T mice brain. CONCLUSIONS: 4e is a natural compound derived highly potent PDE4 inhibitor. We revealed its potential effect in promoting UPS activity to degrade pathogenic proteins associated with PD.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Doenças Neurodegenerativas , Doença de Parkinson , Inibidores da Fosfodiesterase 4 , Animais , Neurônios Dopaminérgicos/metabolismo , Ativação Enzimática/efeitos dos fármacos , Humanos , Camundongos , Camundongos Transgênicos , Doenças Neurodegenerativas/metabolismo , Doença de Parkinson/metabolismo , Inibidores da Fosfodiesterase 4/metabolismo , Inibidores da Fosfodiesterase 4/farmacologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Ratos , Ubiquitina/metabolismo , Xantonas , alfa-Sinucleína/metabolismo
12.
Chin Med ; 17(1): 55, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35524271

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is a highly aggressive subtype of breast cancer that develops resistance to chemotherapy frequently. Autophagy has been reported as a pro-survival response to chemotherapeutic drugs in TNBC, and suppression of autophagy can be a strategy to overcome drug resistance. METHODS: The efficacy of toosendanin (TSN) in blocking autophagy flux was measured by western blot analysis of autophagy markers, and the fluorescent imaging of RFP-GFP-LC3 probe. The co-localization of autophagosomes and lysosomes was analyzed by fluorescent imaging. Then, lysosome function was determined by measuring the lysosomal pH value and the activity of lysosomal hydrolytic proteases. For in vitro study, human triple-negative breast cancer MDA-MB-231 and MDA-MB-436 cell lines were used for evaluating the anti-proliferative effect. For in vivo study, the RFP-GFP-LC3 MDA-MB-231 xenograft nude mice received intraperitoneal injection of irinotecan (10 mg/kg), TSN (0.5 mg/kg) or a combination, and the autophagy activity and cell apoptosis were determined in tumor tissue. The degree of pathological injury of tissue was evaluated by liver index. RESULTS: The natural autophagy inhibitor TSN, a triterpenoid extracted from Melia toosenda Sieb. et Zucc, potently inhibited late-stage autophagy in TNBC cells. This effect was achieved via elevating lysosome pH rather than blocking the fusion of autophagosomes and lysosomes. We further investigated the effects of TSN on the in vitro and in vivo TNBC models, in combination with chemotherapeutic drug irinotecan (or its active metabolite 7-ethyl-10-hydroxycamptothecin), a topoisomerase I inhibitor showing therapeutic potential for TNBC. The data showed that TSN blocked 7-ethyl-10-hydroxycamptothecin (SN-38)/irinotecan-induced protective autophagy, and significantly induced apoptosis in TNBC cells and tumor xenograft models when compared to SN-38/irinotecan alone group.

13.
Acta Pharmacol Sin ; 43(5): 1251-1263, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34417577

RESUMO

Transcriptional factor EB (TFEB), a master regulator of autophagy and lysosomal biogenesis, is generally regarded as a pro-survival factor. Here, we identify that besides its effect on autophagy induction, TFEB exerts a pro-apoptotic effect in response to the cyclopentenone prostaglandin 15-deoxy-∆-12,14-prostaglandin J2 (15d-PGJ2). Specifically, 15d-PGJ2 promotes TFEB translocation from the cytoplasm into the nucleus to induce autophagy and lysosome biogenesis via reactive oxygen species (ROS) production rather than mTORC1 inactivation. Surprisingly, TFEB promotes rather than inhibits apoptosis in response to 15d-PGJ2. Mechanistically, ROS-mediated TFEB translocation into the nucleus transcriptionally upregulates the expression of ATF4, which is required for apoptosis elicited by 15d-PGJ2. Additionally, inhibition of TFEB activation by ROS scavenger N-acetyl cysteine or inhibition of protein synthesis by cycloheximide effectively compromises ATF4 upregulation and apoptosis in response to 15d-PGJ2. Collectively, these results indicate that ROS-induced TFEB activation exerts a novel role in promoting apoptosis besides its role in regulating autophagy in response to 15d-PGJ2. This work not only evidences how TFEB is activated by 15d-PGJ2, but also unveils a previously unexplored role of ROS-dependent activation of TFEB in modulating cell apoptosis in response to 15d-PGJ2.


Assuntos
Prostaglandina D2 , Prostaglandinas , Apoptose , Autofagia , Ciclopentanos , Prostaglandina D2/análogos & derivados , Prostaglandina D2/farmacologia , Prostaglandinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo
14.
Autophagy ; 18(3): 624-642, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34313551

RESUMO

ABBREVIATIONS: Aß: ß-amyloid; AD: Alzheimer disease; AIF1/IBA1: allograft inflammatory factor 1; ALP: autophagy-lysosomal pathway; APP: amyloid beta precursor protein; ATP6V1B1/V-ATPase V1b1: ATPase H+ transporting V1 subunit B1; AVs: autophagy vacuoles; BAF: bafilomycin A1; CFC: contextual/cued fear conditioning assay; CHX: Ca2+/H+ exchanger; CTF-ß: carboxy-terminal fragment derived from ß-secretase; CTSD: cathepsin D; fAD: familial Alzheimer disease; GFAP: glial fibrillary acidic protein; LAMP1: lysosomal associated membrane protein 1; LTP: long-term potentiation; MCOLN1/TRPML1: mucolipin 1; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MAPT: microtubule associated protein tau; MWM: Morris water maze; NFT: neurofibrillary tangles; PFC: prefrontal cortex; PSEN1: presenilin 1; SQSTM1/p62: sequestosome 1; TBS: theta burst stimulation; TEM: transmission electronic microscopy; TPCN2/TPC2: two pore segment channel 2; WT: wild-type; V-ATPase: vacuolar type H+-ATPase.


Assuntos
Doença de Alzheimer , ATPases Vacuolares Próton-Translocadoras , Adenosina Trifosfatases/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Autofagia/fisiologia , Humanos , Lisossomos/metabolismo , Transtornos da Memória/metabolismo , ATPases Vacuolares Próton-Translocadoras/metabolismo
15.
Phytomedicine ; 87: 153578, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34038839

RESUMO

BACKGROUND: Parkinson's disease (PD) is one of the most common neurodegenerative motor disorders, and is characterized by the presence of Lewy bodies containing misfolded α-synuclein (α-syn) and by selective degeneration of midbrain dopamine neurons. Studies have shown that upregulation of ubiquitin-proteasome system (UPS) activity promotes the clearance of aggregation-prone proteins such as α-syn and Tau, so as to alleviate the neuropathology of neurodegenerative diseases. PURPOSE: To identify and investigate lycorine as a UPS enhancer able to decrease α-syn in transgenic PD models. METHODS: Dot blot was used to screen α-syn-lowering compounds in an inducible α-syn overexpression cell model. Inducible wild-type (WT) and mutant α-syn-overexpressing PC12 cells, WT α-syn-overexpressing N2a cells and primary cultured neurons from A53T transgenic mice were used to evaluate the effects of lycorine on α-syn degradation in vitro. Heterozygous A53T transgenic mice were used to evaluate the effects of lycorine on α-syn degradation in vivo. mCherry-GFP-LC3 reporter was used to detect autophagy-dependent degradation. Ub-R-GFP and Ub-G76V-GFP reporters were used to detect UPS-dependent degradation. Proteasome activity was detected by fluorogenic substrate Suc-Leu-Leu-Val-Tyr-AMC (Suc-LLVY-AMC). RESULTS: Lycorine significantly promoted clearance of over-expressed WT and mutant α-syn in neuronal cell lines and primary cultured neurons. More importantly, 15 days' intraperitoneal administration of lycorine effectively promoted the degradation of α-syn in the brains of A53T transgenic mice. Mechanistically, lycorine accelerated α-syn degradation by activating cAMP-dependent protein kinase (PKA) to promote proteasome activity. CONCLUSION: Lycorine is a novel α-syn-lowering compound that works through PKA-mediated UPS activation. This ability to lower α-syn implies that lycorine has the potential to be developed as a pharmaceutical for the treatment of neurodegenerative diseases, such as PD, associated with UPS impairment and protein aggregations.


Assuntos
Alcaloides de Amaryllidaceae/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Doença de Parkinson/tratamento farmacológico , Fenantridinas/farmacologia , alfa-Sinucleína/metabolismo , Animais , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , AMP Cíclico/metabolismo , Modelos Animais de Doenças , Humanos , Masculino , Camundongos Transgênicos , Fármacos Neuroprotetores/farmacologia , Células PC12 , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Ratos , Ubiquitina/metabolismo , Regulação para Cima/efeitos dos fármacos , alfa-Sinucleína/genética
16.
Proc Natl Acad Sci U S A ; 118(14)2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33785595

RESUMO

Autophagy is a catabolic pathway that provides self-nourishment and maintenance of cellular homeostasis. Autophagy is a fundamental cell protection pathway through metabolic recycling of various intracellular cargos and supplying the breakdown products. Here, we report an autophagy function in governing cell protection during cellular response to energy crisis through cell metabolic rewiring. We observe a role of selective type of autophagy in direct activation of cyclic AMP protein kinase A (PKA) and rejuvenation of mitochondrial function. Mechanistically, autophagy selectively degrades the inhibitory subunit RI of PKA holoenzyme through A-kinase-anchoring protein (AKAP) 11. AKAP11 acts as an autophagy receptor that recruits RI to autophagosomes via LC3. Glucose starvation induces AKAP11-dependent degradation of RI, resulting in PKA activation that potentiates PKA-cAMP response element-binding signaling, mitochondria respiration, and ATP production in accordance with mitochondrial elongation. AKAP11 deficiency inhibits PKA activation and impairs cell survival upon glucose starvation. Our results thus expand the view of autophagy cytoprotection mechanism by demonstrating selective autophagy in RI degradation and PKA activation that fuels the mitochondrial metabolism and confers cell resistance to glucose deprivation implicated in tumor growth.


Assuntos
Proteínas de Ancoragem à Quinase A/metabolismo , Autofagia , Mitocôndrias/metabolismo , Neoplasias/metabolismo , Animais , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Camundongos
17.
J Adv Res ; 34: 1-12, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-35024177

RESUMO

Introduction: Alzheimer's disease (AD) is a progressive brain disorder, and one of the most common causes of dementia and amnesia. Due to the complex pathogenesis of AD, the underlying mechanisms remain unclear. Although scientists have made increasing efforts to develop drugs for AD, no effective therapeutic agents have been found. Objectives: Natural products and their constituents have shown promise for treating neurodegenerative diseases, including AD. Thus, in-depth study of medical plants, and the main active ingredients thereof against AD, is necessary to devise therapeutic agents. Methods: In this study, N2a/APP cells and SAMP8 mice were employed as in vitro and in vivo models of AD. Multiple molecular biological methods were used to investigate the potential therapeutic actions of oxyphylla A, and the underlying mechanisms. Results: Results showed that oxyphylla A, a novel compound extracted from Alpinia oxyphylla, could reduce the expression levels of amyloid precursor protein (APP) and amyloid beta (Aß) proteins, and attenuate cognitive decline in SAMP8 mice. Further investigation of the underlying mechanisms showed that oxyphylla A exerted an antioxidative effect through the Akt-GSK3ß and Nrf2-Keap1-HO-1 pathways.Conclusions.Taken together, our results suggest a new horizon for the discovery of therapeutic agents for AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Animais , Caproatos , Cognição , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Cresóis , Modelos Animais de Doenças , Glicogênio Sintase Quinase 3 beta , Proteína 1 Associada a ECH Semelhante a Kelch , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-akt
18.
Transfus Apher Sci ; 59(5): 102825, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32616366

RESUMO

BACKGROUND: Transfusion strategies are involving the survival and prognosis of patients with malignant neoplasm and the rational utilization of medical resources, but there are still controversy between different transfusion strategies. The aim of this article is to compare the benefit and harm of restrictive and liberal red blood cell(RBC) transfusion strategies in patients with malignant tumors. METHODS: We searched articles in the databases of PubMed, Cochrane Library, Web of Science, Embase and major conference proceedings, identified all randomized controlled trials (RCTs) and compared restrictive transfusion strategies with those that are liberal until MARCH 18, 2019. We used risk ratio (RR) and and 95 % confidence interval (95 %CI) to calculate the results of dichotomous variables, and the study heterogeneity was assessed by using the I2 statistics. Also, we did sensitivity analysis and quality assessment. RESULTS: Restrictive transfusion policies appear to have no effect on all-cause mortality (RR 1.33; 95 % CI 0.74-2.38; P = 0.34), compared with liberal policies. 2 trials including 498 patients were included of renal replacement therapy (RR 1.38; 95 % CI, 0.73-2.59; P = 0.32; I2 = 0%). Myocardial infarction (RR 1.17; 95 % CI, 0.33-4.1; P = 0.81; I2 = 0%) and ICU readmission were also mentioned in these articles (RR 1.19; 95 % CI, 0.7-2.04; P = 0.52; I2 = 0%). However, the RR of hospital length can't be evaluated. CONCLUSION: Restrictive transfusion strategies were not associated with all-cause mortality and other clinical outcomes in malignant tumors, and may be more suitable for patients' quality of life and medical economy than liberal.


Assuntos
Transfusão de Sangue/métodos , Neoplasias/terapia , Qualidade de Vida/psicologia , Humanos , Neoplasias/mortalidade , Projetos Piloto , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida
19.
Chin Med ; 15: 29, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32256685

RESUMO

BACKGROUND: Alzheimer's disease (AD) is ranked as the most prevalent neurodegenerative disease. However, the exact molecular mechanisms underlying pathophysiological alterations in AD remain unclear, especially at the prodromal stage. The decreased proteolytic degradation of Aß, blood-brain barrier (BBB) disruption, and neuroinflammation are considered to play key roles in the course of AD. METHODS: Male APPswe/PS1dE9 C57BL/6 J double-transgenic (APP/PS1) mice in the age range from 1 month to 6 months and age-matched wild type mice were used in this study, intending to investigate the expression profiles of Aß-degrading enzymes for Aß degradation activities and zonula occludens-1 (zo-1) for BBB integrity at the prodromal stage. RESULTS: Our results showed that there were no significant genotype-related alterations in mRNA expression levels of 4 well-characterized Aß-degrading enzymes in APP/PS1 mice within the ages of 6 months. Interestingly, a significant decrease in zo-1 expression was observed in APP/PS1 mice starting from the age of 5 months, suggesting that BBB disrupt occurs at an early stage. Moreover, treatment of fish oil (FO) for 4 weeks remarkably increased zo-1 expression and significantly inhibited the glial activation and NF-κB activation in APP/PS1 mice. CONCLUSION: The results of our study suggest that FO supplement could be a potential therapeutic early intervention for AD through protecting the BBB integrity and suppressing glial and NF-κB activation.

20.
Cell Death Dis ; 11(2): 128, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32071296

RESUMO

Autophagy, a conserved cellular degradation and recycling process, can be enhanced by nutrient depletion, oxidative stress or other harmful conditions to maintain cell survival. 6-Hydroxydopamine/ascorbic acid (6-OHDA/AA) is commonly used to induce experimental Parkinson's disease (PD) lesions by causing oxidative damage to dopaminergic neurons. Activation of autophagy has been observed in the 6-OHDA-induced PD models. However, the mechanism and exact role of autophagy activation in 6-OHDA PD model remain inconclusive. In this study, we report that autophagy was triggered via mucolipin 1/calcium/calcineurin/TFEB (transcription factor EB) pathway upon oxidative stress induced by 6-OHDA/AA. Interestingly, overexpression of TFEB alleviated 6-OHDA/AA toxicity. Moreover, autophagy enhancers, Torin1 (an mTOR-dependent TFEB/autophagy enhancer) and curcumin analog C1 (a TFEB-dependent and mTOR-independent autophagy enhancer), significantly rescued 6-OHDA/AA-induced cell death in SH-SY5Y cells, iPSC-derived DA neurons and mice nigral DA neurons. The behavioral abnormality of 6-OHDA/AA-treated mice can also be rescued by Torin 1 or C1 administration. The protective effects of Torin 1 and C1 can be blocked by autophagy inhibitors like chloroquine (CQ) or by knocking down autophagy-related genes TFEB and ATG5. Taken together, this study supports that TFEB-mediated autophagy is a survival mechanism during oxidative stress and pharmacological enhancement of this process is a neuroprotective strategy against oxidative stress-associated PD lesions.


Assuntos
Antiparkinsonianos/farmacologia , Autofagia/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Encéfalo/efeitos dos fármacos , Curcumina/farmacologia , Neurônios Dopaminérgicos/efeitos dos fármacos , Naftiridinas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Transtornos Parkinsonianos/tratamento farmacológico , Animais , Ácido Ascórbico , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Comportamento Animal/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Linhagem Celular Tumoral , Curcumina/análogos & derivados , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Feminino , Humanos , Camundongos Endogâmicos C57BL , Mitofagia/efeitos dos fármacos , Oxidopamina , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/patologia , Transdução de Sinais , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo
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