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1.
Heliyon ; 9(8): e19147, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37664750

RESUMO

Recent immunotherapy research has focused on chimeric antigen receptor-modified T cells (CAR-Ts). CAR-T therapies have been clinically applied to manage hematologic malignancies with satisfactory effectiveness. However, the application of CAR-T immunotherapy in solid tumors remains challenging. Even so, current CAR-T immunotherapies for prostate cancer (PCa) have shown some promise, giving hope to patients with advanced metastatic PCa. This review aimed to elucidate different types of prostate tumor-associated antigen targets, such as prostate-specific membrane antigen and prostate stem cell antigen, and their effects. The current status of the corresponding targets in clinical research through their applications was also discussed. To improve the efficacy of CAR-T immunotherapy, we addressed the possible applications of multimodal immunotherapy, chemotherapy, and CAR-T combined therapies. The obstacles of solid tumors were concisely elaborated. Further studies should aim to discover novel potential targets and establish new models by overcoming the inherent barriers of solid tumors, such as tumor heterogeneity and the immunosuppressive nature of the tumor microenvironment.

2.
EMBO J ; 42(11): e112940, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37038975

RESUMO

The peptide hormone angiotensin II regulates blood pressure mainly through the type 1 angiotensin II receptor AT1 R and its downstream signaling proteins Gq and ß-arrestin. AT1 R blockers, clinically used as antihypertensive drugs, inhibit both signaling pathways, whereas AT1 R ß-arrestin-biased agonists have shown great potential for the treatment of acute heart failure. Here, we present a cryo-electron microscopy (cryo-EM) structure of the human AT1 R in complex with a balanced agonist, Sar1 -AngII, and Gq protein at 2.9 Å resolution. This structure, together with extensive functional assays and computational modeling, reveals the molecular mechanisms for AT1 R signaling modulation and suggests that a major hydrogen bond network (MHN) inside the receptor serves as a key regulator of AT1 R signal transduction from the ligand-binding pocket to both Gq and ß-arrestin pathways. Specifically, we found that the MHN mutations N1113.35 A and N2947.45 A induce biased signaling to Gq and ß-arrestin, respectively. These insights should facilitate AT1 R structure-based drug discovery for the treatment of cardiovascular diseases.


Assuntos
Angiotensina II , Transdução de Sinais , Humanos , Microscopia Crioeletrônica , Transdução de Sinais/fisiologia , beta-Arrestinas/metabolismo , Angiotensina II/química , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Receptores de Angiotensina/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(6): e2216230120, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36724251

RESUMO

Gastrin releasing peptide receptor (GRPR), a member of the bombesin (BBN) G protein-coupled receptors, is aberrantly overexpressed in several malignant tumors, including those of the breast, prostate, pancreas, lung, and central nervous system. Additionally, it also mediates non-histaminergic itch and pathological itch conditions in mice. Thus, GRPR could be an attractive target for cancer and itch therapy. Here, we report the inactive state crystal structure of human GRPR in complex with the non-peptide antagonist PD176252, as well as two active state cryo-electron microscopy (cryo-EM) structures of GRPR bound to the endogenous peptide agonist gastrin-releasing peptide and the synthetic BBN analog [D-Phe6, ß-Ala11, Phe13, Nle14] Bn (6-14), in complex with Gq heterotrimers. These structures revealed the molecular mechanisms for the ligand binding, receptor activation, and Gq proteins signaling of GRPR, which are expected to accelerate the structure-based design of GRPR antagonists and agonists for the treatments of cancer and pruritus.


Assuntos
Neoplasias , Receptores da Bombesina , Masculino , Humanos , Camundongos , Animais , Receptores da Bombesina/agonistas , Receptores da Bombesina/metabolismo , Microscopia Crioeletrônica , Bombesina/farmacologia , Peptídeo Liberador de Gastrina/metabolismo , Prurido/metabolismo
4.
Nanomaterials (Basel) ; 12(14)2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35889730

RESUMO

AlGaN nanorods have attracted increasing amounts of attention for use in ultraviolet (UV) optoelectronic devices. Here, self-assembled AlGaN nanorods with embedding quantum disks (Qdisks) were grown on Si(111) using plasma-assisted molecular beam epitaxy (PA-MBE). The morphology and quantum construction of the nanorods were investigated and well-oriented and nearly defect-free nanorods were shown to have a high density of about 2 × 1010 cm-2. By controlling the substrate temperature and Al/Ga ratio, the emission wavelengths of the nanorods could be adjusted from 276 nm to 330 nm. By optimizing the structures and growth parameters of the Qdisks, a high internal quantum efficiency (IQE) of the AlGaN Qdisk nanorods of up to 77% was obtained at 305 nm, which also exhibited a shift in the small emission wavelength peak with respect to the increasing temperatures during the PL measurements.

5.
Comput Intell Neurosci ; 2022: 2419175, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35769274

RESUMO

National dance is an important symbol of national spiritual culture, as it embodies each nation's unique history, living habits, ideology, and culture. Many Chinese ethnic groups have developed their own dance forms and styles, each with their own set of charms. Strengthening our understanding of its style and characteristics is critical to our understanding of the national dance. To begin with, this paper proposes a patch-based multiview stereo reconstruction scheme that can accurately reconstruct 3D character models. The movement capture system then collects national dance movement data and uses them to drive a three-dimensional character model that generates dance visual animation. In the human skeleton model, a spatial-temporal HMM (hidden Markov model) is proposed that not only studies the temporal information of human movements but also the spatial information of adjacent connection points. The recognition rate of this algorithm increases to 95.68 percent when the number of setting points is increased to ten and to 98.28 percent when the number of setting points is increased to twenty, according to the research. The experimental results show that the 3D reconstruction model of ethnic dance developed in this paper is capable of meeting the goal of ethnic dance digitalization while being simple to use, being low in cost, and with a good display effect.


Assuntos
Dança , Algoritmos , Humanos , Imageamento Tridimensional , Movimento
6.
Nat Commun ; 13(1): 714, 2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-35132089

RESUMO

The type 2 bradykinin receptor (B2R) is a G protein-coupled receptor (GPCR) in the cardiovascular system, and the dysfunction of B2R leads to inflammation, hereditary angioedema, and pain. Bradykinin and kallidin are both endogenous peptide agonists of B2R, acting as vasodilators to protect the cardiovascular system. Here we determine two cryo-electron microscopy (cryo-EM) structures of human B2R-Gq in complex with bradykinin and kallidin at 3.0 Å and 2.9 Å resolution, respectively. The ligand-binding pocket accommodates S-shaped peptides, with aspartic acids and glutamates as an anion trap. The phenylalanines at the tail of the peptides induce significant conformational changes in the toggle switch W2836.48, the conserved PIF, DRY, and NPxxY motifs, for the B2R activation. This further induces the extensive interactions of the intracellular loops ICL2/3 and helix 8 with Gq proteins. Our structures elucidate the molecular mechanisms for the ligand binding, receptor activation, and Gq proteins coupling of B2R.


Assuntos
Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/química , Receptor B2 da Bradicinina/química , Sequência de Aminoácidos , Sítios de Ligação , Bradicinina/química , Bradicinina/metabolismo , Microscopia Crioeletrônica , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Humanos , Calidina/química , Calidina/metabolismo , Ligantes , Modelos Moleculares , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Receptor B2 da Bradicinina/metabolismo
7.
Sci Total Environ ; 823: 153545, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35104526

RESUMO

An influence of precipitation on the glacier changes over the Qinghai-Tibet Plateau (QTP) is investigated in this paper. The results show that the glacial loss rates of glaciers in the QTP are significantly correlated with the interannual changes of precipitation and low cloud cover. The water vapor, importing with the warm and wet airflows from the Asian Monsoon regions, significantly influence the precipitation in the southern and northern glacier areas of the QTP in the summer monsoon season. The three-dimensional changes of water vapor transport can lead to the difference of water balance between different glacier areas. Under global warming, the northwest QTP is in the ascending branch of the vertical water driven thermally by the tropical Indian Ocean. The warm water vapor from the tropical ocean climbs to the QTP, forming a significant supply effect of precipitation in the northwestern glacier area, which makes the glacier retreat at a relatively slow rate. Meanwhile, the southern and southeastern QTP regions are in the descending branch of vapor transport with the declining trend in the lower troposphere, which lead to the shortage water supply aggravating the glacier loss in the southern and southeastern QTP.


Assuntos
Monitoramento Ambiental , Camada de Gelo , Vapor , Aquecimento Global , Oceano Índico , Estações do Ano , Tibet , Clima Tropical
8.
ACS Appl Mater Interfaces ; 13(35): 42125-42137, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34432420

RESUMO

Photoassisted electrocatalysis (P-EC) emerges as a rising star for hydrogen production by embedding photoactive species in electrocatalysts, for which the interfacial structure design and charge transfer kinetics of the multifunctional catalysts remain a great challenge. Herein, Zn-AgIn5S8 quantum dots (ZAIS QDs) were embedded into 2D NiFe layered double hydroxide nanosheets through a simple hydrothermal treatment to form 0D/2D composite catalysts for P-EC. With evidence from transient photovoltage spectroscopy, we acquired a clear and fundamental understanding on the kinetics of charge extraction time and extraction amount in the 0D/2D heterojunctions that was proved to play a key role in P-EC. Upon light illumination, for HER, the optimized NiFe-ZAIS exhibits obviously reduced overpotentials of 129 and 242 mV at current densities of 10 and 50 mA cm-2, which are 22 and 33 mV lower than those of dark electrocatalysis, respectively. For OER, the NiFe-ZAIS electrode also shows low overpotentials of 220 and 268 mV at current densities of 10 and 50 mA cm-2, respectively, under light illumination, which were able to almost double the intrinsic activity. Finally, with NF@NiFe-ZAIS as both the cathode and the anode, the assembled electrolyzer only requires 1.62 V to reach the overall water splitting current density of 10 mA cm-2 under P-EC. This work provides a useful example for the profound understanding of the design and the kinetics study of multifunctional P-EC catalysts.

9.
J Mol Med (Berl) ; 99(10): 1427-1446, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34180022

RESUMO

In this study, we show that during normal rat pregnancy, there is a gestational stage-dependent decrease in androgen receptor (AR) abundance in the gravid uterus and that this is correlated with the differential expression of endometrial receptivity and decidualization genes during early and mid-gestation. In contrast, exposure to 5α-dihydrotestosterone (DHT) and insulin (INS) or DHT alone significantly increased AR protein levels in the uterus in association with the aberrant expression of endometrial receptivity and decidualization genes, as well as disrupted implantation. Next, we assessed the functional relevance of the androgen-AR axis in the uterus for reproductive outcomes by treating normal pregnant rats and pregnant rats exposed to DHT and INS with the anti-androgen flutamide. We found that AR blockage using flutamide largely attenuated the DHT and INS-induced maternal endocrine, metabolic, and fertility impairments in pregnant rats in association with suppressed induction of uterine AR protein abundance and androgen-regulated response protein and normalized expression of several endometrial receptivity and decidualization genes. Further, blockade of AR normalized the expression of the mitochondrial biogenesis marker Nrf1 and the mitochondrial functional proteins Complexes I and II, VDAC, and PHB1. However, flutamide treatment did not rescue the compromised mitochondrial structure resulting from co-exposure to DHT and INS. These results demonstrate that functional AR protein is an important factor for gravid uterine function. Impairments in the uterine androgen-AR axis are accompanied by decreased endometrial receptivity, decidualization, and mitochondrial dysfunction, which might contribute to abnormal implantation in pregnant PCOS patients with compromised pregnancy outcomes and subfertility. KEY MESSAGES: The proper regulation of uterine androgen receptor (AR) contributes to a normal pregnancy process, whereas the aberrant regulation of uterine AR might be linked to polycystic ovary syndrome (PCOS)-induced pregnancy-related complications. In the current study, we found that during normal rat pregnancy there is a stage-dependent decrease in AR abundance in the gravid uterus and that this is correlated with the differential expression of the endometrial receptivity and decidualization genes Spp1, Prl, Igfbp1, and Hbegf. Pregnant rats exposed to 5α-dihydrotestosterone (DHT) and insulin (INS) or to DHT alone show elevated uterine AR protein abundance and implantation failure related to the aberrant expression of genes involved in endometrial receptivity and decidualization in early to mid-gestation. Treatment with the anti-androgen flutamide, starting from pre-implantation, effectively prevents DHT + INS-induced defects in endometrial receptivity and decidualization gene expression, restores uterine mitochondrial homeostasis, and increases the pregnancy rate and the numbers of viable fetuses. This study adds to our understanding of the mechanisms underlying poor pregnancy outcomes in PCOS patients and the possible therapeutic use of anti-androgens, including flutamide, after spontaneous conception.


Assuntos
Implantação do Embrião/fisiologia , Hiperandrogenismo/metabolismo , Resistência à Insulina/fisiologia , Insulina/metabolismo , Mitocôndrias/metabolismo , Receptores Androgênicos/metabolismo , Útero/metabolismo , Androgênios/metabolismo , Animais , Decídua/metabolismo , Di-Hidrotestosterona/metabolismo , Endométrio/metabolismo , Feminino , Masculino , Síndrome do Ovário Policístico/metabolismo , Gravidez , Ratos , Ratos Sprague-Dawley
10.
Artigo em Inglês | MEDLINE | ID: mdl-33986820

RESUMO

Female infertility is a state of fertility disorder caused by multiple reasons. The incidence of infertility for females has significantly increased due to various factors such as social pressure, late marriage, and late childbirth, and its harm includes heavy economic burden, psychological shadow, and even marriage failure. Conventional solutions, such as hormone therapy, in vitro fertilization (IVF), and embryo transfer, have the limitations of unsatisfied obstetric outcomes and serious adverse events. Currently, complementary and alternative medicine (CAM), as a new treatment for infertility, is gradually challenging the dominant position of traditional therapies in the treatment of infertility. CAM claims that it can adjust and harmonize the state of the female body from a holistic approach to achieve a better therapeutic effect and has been increasingly used by infertile women. Meanwhile, some controversial issues also appeared; that is, some randomized controlled trials (RCTs) confirmed that CAM had no obvious effect on infertility, and the mechanism of its effect could not reach a consensus. To clarify CAM effectiveness, safety, and mechanism, this paper systematically reviewed the literature about its treatment of female infertility collected from PubMed and CNKI databases and mainly introduced acupuncture, moxibustion, and oral Chinese herbal medicine. In addition, we also briefly summarized psychological intervention, biosimilar electrical stimulation, homeopathy, hyperbaric oxygen therapy, etc.

11.
Materials (Basel) ; 14(2)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466941

RESUMO

Laser polishing is a widely used technology to improve the surface quality of the products. However, the investigation on the physical mechanism is still lacking. In this paper, the established numerical transient model reveals the rough surface evolution mechanism during laser polishing. Mass transfer driven by Marangoni force, surface tension and gravity appears in the laser-induced molten pool so that the polished surface topography tends to be smoother. The AlSi10Mg samples fabricated by laser-based powder bed fusion were polished at different laser hatching spaces, passes and directions to gain insight into the variation of the surface morphologies, roughness and microhardness in this paper. The experimental results show that after laser polishing, the surface roughness of Ra and Sa of the upper surface can be reduced from 12.5 µm to 3.7 µm and from to 29.3 µm to 8.4 µm, respectively, due to sufficient wetting in the molten pool. The microhardness of the upper surface can be elevated from 112.3 HV to 176.9 HV under the combined influence of the grain refinement, elements distribution change and surface defects elimination. Better surface quality can be gained by decreasing the hatching space, increasing polishing pass or choosing apposite laser direction.

12.
Front Pharmacol ; 11: 625108, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33569009

RESUMO

Zhi-zi-chi Decoction (ZZCD), composed of Fructus Gardeniae (Zhizi in Chinese, ZZ in brief) and Semen sojae praeparatum (Dandouchi in Chinese, DDC in brief), has been used as a drug therapy for depression for thousands of years in China. However, the antidepressant mechanism of ZZCD still remains unknown. This study was aimed at exploring antidepressant effects of ZZCD from the aspect of neuroprotection based on herb compatibility. Glutamate-treated PC12 cells and chronic unpredictable mild stress (CUMS)-induced rats were established as models of depression in vitro and in vivo respectively. Cell viability, lactate dehydrogenase (LDH), apoptosis rate, reactive oxygen species (ROS), glutathione reductase (GR) and superoxide dismutase (SOD), and the expressions of Bax, Bcl-2 and cyclic adenosine monophosphate-response element binding protein (CREB) were measured to compare neuroprotection among single herbs and the formula in vitro. Behavior tests were conducted to validate antidepressant effects of ZZCD in vivo. Results showed that the compatibility of ZZ and DDC increased cell viability and activities of GR and SOD, and decreased the levels of LDH, apoptosis cells and ROS. Besides, the expressions of Bcl-2 and CREB were up-regulated while that of Bax was down-regulated by ZZCD. Furthermore, the compatibility of ZZ and DDC reversed abnormal behaviors in CUMS-induced rats and displayed higher efficacy than any of the single herbs. This study revealed that the antidepressant effects of ZZCD were closely associated with neuroprotection and elucidated synergistic effects of the compatibility of ZZ and DDC based on it.

13.
Biomed Res Int ; 2019: 6769789, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31139644

RESUMO

OBJECTIVE: Observe the protective effect of chlorogenic acid on dextran sulfate-induced ulcerative colitis in mice and explore the regulation of MAPK/ERK/JNK signaling pathway. METHODS: Seventy C57BL/6 mice (half males and half females) were randomly divided into 7 groups, 10 in each group: control group (CON group), UC model group (UC group), and sulfasalazine-positive control group (SASP group), chlorogenic acid low dose group (CGA-L group), chlorogenic acid medium dose group (CGA-M group), chlorogenic acid high dose group (CGA-H group), and ERK inhibitor + chlorogenic acid group (E+CGA group). The effects of chlorogenic acid on UC were evaluated by colon mucosa damage index (CMDI), HE staining, immunohistochemistry, ELISA, and Western blot. The relationship between chlorogenic acid and MAPK/ERK/JNK signaling pathway was explored by adding ERK inhibitor. RESULTS: The UC models were established successfully by drinking DSS water. Chlorogenic acid reduces DSS-induced colonic mucosal damage, inhibits DSS-induced inflammation, oxidative stress, and apoptosis in colon, and reduces ERK1/2, p -ERK, p38, p-p38, JNK, and p-JNK protein expression. ERK inhibitor U0126 reversed the protective effect of chlorogenic acid on colon tissue. CONCLUSION: Chlorogenic acid can alleviate DSS-induced ulcerative colitis in mice, which can significantly reduce tissue inflammation and apoptosis, and its mechanism is related to the MAPK/ERK/JNK signaling pathway.


Assuntos
Ácido Clorogênico/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/enzimologia , Sistema de Sinalização das MAP Quinases , Animais , Apoptose , Ácido Clorogênico/química , Ácido Clorogênico/farmacologia , Colite Ulcerativa/induzido quimicamente , Colo/patologia , Sulfato de Dextrana , Feminino , Inflamação/complicações , Inflamação/patologia , Mucosa Intestinal/patologia , Masculino , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos
14.
Artigo em Inglês | MEDLINE | ID: mdl-29202054

RESUMO

BACKGROUND: China's Reform and Open up Policy in 1980s has brought rapid economic development to Chinese society. With the deepening of economic reform, the withdrawal of the state in China has had visible and worrisome consequences for health and for the functioning of health services. The new round of healthcare reform after 2009 has made significant achievements on improving fundamental health and bringing back the nature of welfare of health. However, the financing mechanism of health system has not been established, and the underlying reason behind the healthcare reform dilemma and the theoretical solution need to be found. METHODS: This study used the methods of literature review, theoretical research and comparative research to summarize and analyze the reasons and solutions of current dilemma in healthcare reform, and created the new discipline of health fiscalogy through theoretical analysis and vertical and horizontal comparison of healthcare system, especially health financing. RESULTS: Dilemma in healthcare system emerged from the circumstances of rapid process of industrialization, urbanization and population aging, including the profit-driven phenomena, tendency of excessive marketization in public hospitals, strained doctor-patient relationship, high disease burden on individuals and families, and so on. It can be concluded that the theoretical basis of healthcare system and the nature of health resources are crucial in solving the dilemma of healthcare reform. The theoretical basis of healthcare reform should be health fiscalogy focusing on government as the main body of health care responsibility rather than health economics focusing on anti-monopoly. There are two key differences between health economics and health fiscalogy: responsible person/department of disease and health welfare, and nature of resource. The new discipline of health fiscalogy has universal and important implications on both China's healthcare reform and the healthcare reform in the world. CONCLUSIONS: China's healthcare reform should return from the paradigm of health economics and marketization financing model to the paradigm of health fiscalogy and government-led financing model, which is reflected in the main position of government and social welfare.

15.
PLoS One ; 10(6): e0126235, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26039088

RESUMO

BACKGROUND: The widely distributed glaciers in the greater Himalayan region have generally experienced rapid shrinkage since the 1850s. As invaluable sources of water and because of their scarcity, these glaciers are extremely important. Beginning in the twenty-first century, new methods have been applied to measure the mass budget of these glaciers. Investigations have shown that the albedo is an important parameter that affects the melting of Himalayan glaciers. METHODOLOGY/PRINCIPAL FINDINGS: The surface albedo based on the Moderate Resolution Imaging Spectroradiometer (MODIS) data over the Hindu Kush, Karakoram and Himalaya (HKH) glaciers is surveyed in this study for the period 2000-2011. The general albedo trend shows that the glaciers have been darkening since 2000. The most rapid decrease in the surface albedo has occurred in the glacial area above 6000 m, which implies that melting will likely extend to snow accumulation areas. The mass-loss equivalent (MLE) of the HKH glacial area caused by surface shortwave radiation absorption is estimated to be 10.4 Gt yr-1, which may contribute to 1.2% of the global sea level rise on annual average (2003-2009). CONCLUSIONS/SIGNIFICANCE: This work probably presents a first scene depicting the albedo variations over the whole HKH glacial area during the period 2000-2011. Most rapidly decreasing in albedo has been detected in the highest area, which deserves to be especially concerned.


Assuntos
Mudança Climática/história , Camada de Gelo , Neve , História do Século XXI
16.
Mol Neurodegener ; 10: 4, 2015 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-26013581

RESUMO

BACKGROUND: Compelling evidence suggests that inhibition of the complex I of the electron transport chain and elevated oxidative stress are the earliest events during the pathogenesis of Parkinson's disease (PD). Therefore, anti-oxidants, especially those from natural sources, hold good promise in treating PD as demonstrated mostly by the studies in rodent models. RESULTS: Herein, we determined if polydatin (piceid), a natural polyphenol, could exert anti-oxidative activity and attenuate dopaminergic neurodegeneration in three commonly used rodent models of PD. Male Sprague Dawley rats given rotenone subcutaneously for 5 weeks developed all the essential features of PD, including a strong increase in catalepsy score and a decrease in motor coordination activity, starting at 4 weeks. Selective increase in oxidative damage was found in the striatal region as compared to the hippocampus and cortex, accompanied by massive degeneration of dopaminergic neurons in the substantia nigra (SNc). Co-administration of piceid orally was able to attenuate rotenone-induced motor defects in a dose dependent manner, with 80 mg/kg dosage showing even better effect than L-levodopa (L-dopa). Piceid treatment significantly prevented the rotenone-induced changes in the levels of glutathione, thioredoxin, ATP, malondialdehyde (MDA) and the manganese superoxide dismutases (SOD) in striatum. Furthermore, piceid treatment rescued rotenone-induced dopaminergic neurodegeneration in the SNc region. Similar protective effect of piceid was also observed in two additional models of PD, MPTP in mice and 6-OHDA in rats, showing corrected motor functions, SOD and MDA activities as well as p-Akt and activated caspase-3 levels. CONCLUSION: In three rodent models of PD, piceid preserves and corrects several major anti-oxidant pathways/parameters selectively in the affected SNc region. This implies its potent anti-oxidant activity as one major underscoring mechanism for protecting the vulnerable SNc neurodegeneration in these models. Taken together, these findings strongly suggest a therapeutic potential of piceid in treating PD.


Assuntos
Neurônios Dopaminérgicos/efeitos dos fármacos , Glucosídeos/farmacologia , Fármacos Neuroprotetores/farmacologia , Oxidantes/antagonistas & inibidores , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/patologia , Estilbenos/farmacologia , Substância Negra/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Modelos Animais de Doenças , Neurônios Dopaminérgicos/patologia , Masculino , Camundongos Endogâmicos C57BL , Neurônios Motores/efeitos dos fármacos , Degeneração Neural , Estresse Oxidativo/fisiologia , Ratos Sprague-Dawley , Substância Negra/patologia
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