RESUMO
The pivotal roles of gut microbiota in severe acute pancreatitis-associated acute lung injury (SAP-ALI) are increasingly revealed, and recent discoveries in the gut-lung axis have provided potential approaches for treating SAP-ALI. Qingyi decoction (QYD), a traditional Chinese medicine (TCM), is commonly used in clinical to treat SAP-ALI. However, the underlying mechanisms remain to be fully elucidated. Herein, by using a caerulein plus lipopolysaccharide (LPS)-induced SAP-ALI mice model and antibiotics (Abx) cocktail-induced pseudogermfree mice model, we tried to uncover the roles of the gut microbiota by administration of QYD and explored its possible mechanisms. Immunohistochemical results showed that the severity of SAP-ALI and intestinal barrier functions could be affected by the relative depletion of intestinal bacteria. The composition of gut microbiota was partially recovered after QYD treatment with decreased Firmicutes/Bacteroidetes ratio and increased relative abundance in short-chain fatty acids (SCFAs)-producing bacteria. Correspondingly increased levels of SCFAs (especially propionate and butyrate) in feces, gut, serum, and lungs were observed, generally consistent with changes in microbes. Western-blot analysis and RT-qPCR results indicated that the AMPK/NF-κB/NLRP3 signaling pathway was activated after oral administration of QYD, which was found to be possibly related to the regulatory effects on SCFAs in the intestine and lungs. In conclusion, our study provides new insights into treating SAP-ALI through modulating the gut microbiota and has prospective practical value for clinical use in the future. IMPORTANCE Gut microbiota affects the severity of SAP-ALI and intestinal barrier function. During SAP, a significant increase in the relative abundance of gut pathogens (Escherichia, Enterococcus, Enterobacter, Peptostreptococcus, Helicobacter) was observed. At the same time, QYD treatment decreased pathogenic bacteria and increased the relative abundance of SCFAs-producing bacteria (Bacteroides, Roseburia, Parabacteroides, Prevotella, Akkermansia). In addition, The AMPK/NF-κB/NLRP3 pathway mediated by SCFAs along the gut-lung axis may play an essential role in preventing the pathogenesis of SAP-ALI, which allows for reduced systemic inflammation and restoration of the intestinal barrier.
Assuntos
Lesão Pulmonar Aguda , Microbioma Gastrointestinal , Pancreatite , Camundongos , Animais , Pancreatite/tratamento farmacológico , Pancreatite/induzido quimicamente , Pancreatite/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Proteínas Quinases Ativadas por AMP/uso terapêutico , Doença Aguda , Estudos Prospectivos , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/metabolismo , Ácidos Graxos VoláteisRESUMO
Qingyi decoction (QYD) has anti-inflammatory pharmacological properties and substantial therapeutic benefits on severe acute pancreatitis (SAP) in clinical practice. However, its protective mechanism against SAP-associated acute lung injury (ALI) remains unclear. In this study, we screened the active ingredients of QYD from the perspective of network pharmacology to identify its core targets and signaling pathways against SAP-associated ALI. Rescue experiments were used to determine the relationship between QYD and ferroptosis. Then, metabolomics and 16s rDNA sequencing were used to identify differential metabolites and microbes in lung tissue. Correlation analysis was utilized to explore the relationship between core targets, signaling pathways, metabolic phenotypes, and microbial flora, sorting out the potential molecular network of QYD against SAP-associated lung ALI. Inflammatory damage was caused by SAP in the rat lung. QYD could effectively alleviate lung injury, improve respiratory function, and significantly reduce serum inflammatory factor levels in SAP rats. Network pharmacology and molecular docking identified three key targets: ALDH2, AnxA1, and ICAM-1. Mechanistically, QYD may inhibit ferroptosis by promoting the ALDH2 expression and suppress neutrophil infiltration by blocking the cleavage of intact AnxA1 and downregulating ICAM-1 expression. Ferroptosis activator counteracts the pulmonary protective effect of QYD in SAP rats. In addition, seven significant differential metabolites were identified in lung tissues. QYD relatively improved the lung microbiome's abundance in SAP rats. Further correlation analysis determined the correlation between ferroptosis, differential metabolites, and differential microbes. In this work, the network pharmacology, metabolomics, and 16s rDNA sequencing were integrated to uncover the mechanism of QYD against SAP-associated ALI. This novel integrated method may play an important role in future research on traditional Chinese medicine.
Assuntos
Lesão Pulmonar Aguda , Ferroptose , Pancreatite , Ratos , Animais , Pancreatite/tratamento farmacológico , Molécula 1 de Adesão Intercelular , Doença Aguda , Simulação de Acoplamento Molecular , Pulmão/metabolismo , Lesão Pulmonar Aguda/metabolismoRESUMO
The improvement of reproductive capacity of poultry is important for the poultry industry. The existing studies on reproductive capacity mainly focus on the testis tissue, but few reports on regulationary effect of brain neuroendocrime on reproductive capacity have been available. The hypothalamus-pituitarium-gonad (HPG) axis is an important pathway regulating spermatogenesis and sexual behavior. This study analyzed the gene expression in the hypothalamus and pituitary tissues of male ducks in high-semen-quality group (DH), low-semen-quality group (DL), and non-response group (DN) by RNA-sequencing. A total of 1980 differentially expressed genes (DEGs) were identified, and significantly less DEGs were found in pituitary gland than in hypothalamus. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that these DEGs were mainly enriched in nerve-related and synapse-related biological processes, mitochondrial inner membrane formation pathway, and ribosome structure pathway. Notably, the neuroactive ligand-receptor interaction pathway significantly enriched in all three comparisons (DH vs. DL, DH vs. DN, and DL vs. DN) was related to different reproductive performance such as semen quality and sexual response. Furthermore, six genes, including POMC, CPLX2, HAPLN2, EGR4, TOX3, and MSH4, were identified as candidate genes regulating reproductive capacity. Our findings provide new insights into the regulation mechanisms underlying the reproductive performance of male poultry, and offer a valuable reference for duck breeding programs aimed at promoting reproductive capacity.
Individual reproductive capacity is crucial to poultry breeding and reproduction. The hypothalamuspituitariumgonad (HPG) axis is an important pathway regulating animal spermatogenesis and sexual behavior. This study identified the neuroactive ligandreceptor interaction pathway as the potential biological pathway regulating the semen quality and sexual behavior by differential transcriptome analysis of the hypothalamus and pituitarium of male ducks. Genes including proopiomelanocortin (POMC), complexin 2 (CPLX2), hyaluronan and proteoglycan link protein 2 (HAPLN2), early growth response 4 (EGR4), tox high mobility group box family member 3 (TOX3), and muts homolog 4 (MSH4) were identified as key candidate genes affecting the HPG axis. Our findings provide new insights into the regulatory mechanisms underlying reproductive performance in male poultry and offer a reference for breeding programs aimed to improve reproductive performance in ducks.
Assuntos
Patos , Transcriptoma , Masculino , Animais , Patos/genética , Análise do Sêmen/veterinária , Perfilação da Expressão Gênica/veterinária , Hipotálamo/metabolismoRESUMO
BACKGROUND: Recent studies have demonstrated that dysfunction of the intestinal barrier is a significant contributing factor to the development of severe acute pancreatitis (SAP). A stable intestinal mucosa barrier functions as a major anatomic and functional barrier, owing to the balance between intestinal epithelial cell (IEC) proliferation and apoptosis. There is some evidence that calcium overload may trigger IEC apoptosis and that calcineurin (CaN)/nuclear factor of activated T-cells (NFAT) signaling might play an important role in calcium-mediated apoptosis. AIM: To investigate the potential mechanisms underlying the therapeutic effect of Qingyi decoction (QYD) in SAP. METHODS: A rat model of SAP was created via retrograde infusion of sodium deoxycholate. Serum levels of amylase, tumor necrosis factor (TNF-α), interleukin (IL)-6, D-lactic acid, and diamine oxidase (DAO); histological changes; and apoptosis of IECs were examined in rats with or without QYD treatment. The expression of the two subunits of CaN and NFAT in intestinal tissue was measured via quantitative real-time polymerase chain reaction and western blotting. For in vitro studies, Caco-2 cells were treated with lipopolysaccharide (LPS) and QYD serum, and then cell viability and intracellular calcium levels were detected. RESULTS: Retrograde infusion of sodium deoxycholate increased the severity of pancreatic and intestinal pathology and the levels of serum amylase, TNF-α, and IL-6. Both the indicators of intestinal mucosa damage (D-lactic acid and DAO) and the levels of IEC apoptosis were elevated in the SAP group. QYD treatment reduced the serum levels of amylase, TNF-α, IL-6, D-lactic acid, and DAO and attenuated the histological findings. IEC apoptosis associated with SAP was ameliorated under QYD treatment. In addition, the protein expression levels of the two subunits of CaN were remarkably elevated in the SAP group, and the NFATc3 gene was significantly upregulated at both the transcript and protein levels in the SAP group compared with the control group. QYD significantly restrained CaN and NFATc3 gene expression in the intestine, which was upregulated in the SAP group. Furthermore, QYD serum significantly decreased the LPS-induced elevation in intracellular free Ca2+ levels and inhibited cell death. CONCLUSION: QYD can exert protective effects against intestinal mucosa damage caused by SAP and the protective effects are mediated, at least partially, by restraining IEC apoptosis via the CaN/NFATc3 pathway.
Assuntos
Amina Oxidase (contendo Cobre) , Pancreatite , Doença Aguda , Amina Oxidase (contendo Cobre)/metabolismo , Amina Oxidase (contendo Cobre)/farmacologia , Amilases , Animais , Células CACO-2 , Calcineurina/efeitos adversos , Calcineurina/metabolismo , Cálcio/metabolismo , Ácido Desoxicólico/metabolismo , Ácido Desoxicólico/farmacologia , Ácido Desoxicólico/uso terapêutico , Medicamentos de Ervas Chinesas , Células Epiteliais/patologia , Humanos , Interleucina-6/metabolismo , Mucosa Intestinal/patologia , Ácido Láctico/metabolismo , Lipopolissacarídeos/farmacologia , Pancreatite/patologia , Ratos , Ratos Sprague-Dawley , Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Impaired intestinal barrier function and gut microbiota dysbiosis are believed to be related to exacerbation of acute pancreatitis (AP). As a bacterial cell wall peptidoglycan component, diaminopimelic acid (DAP) is a specific ligand of NOD1 that regulates the NOD1/RIP2/NF-kB signaling pathway. Here, we investigated the role of DAP in the crosstalk between the gut microbiota and pancreas during the occurrence of AP. Upregulation of NOD1/RIP2/NF-kB and elevated serum DAP levels were found in severe AP (SAP) model rats. The accumulation of DAP in SAP patients corroborated its ability to serve as an indicator of disease severity. Subsequently, SAP rats were treated with oral administration of the traditional Chinese medicine Qingyi Keli (QYKL) as well as neomycin, which can widely eliminate DAP-containing bacteria. Both QYKL and neomycin intervention ameliorated intestinal and pancreatic damage and systemic inflammation in SAP rats. Through 16S rDNA sequencing, we found that QYKL could rehabilitate the gut microbiota structure and selectively inhibit the overgrowth of enteric bacteria, such as Helicobacter and Lactobacillus, in SAP rats without affecting some protective strains, including Romboutsia and Allobaculum. Interestingly, we demonstrated that the decrease in serum DAP was accompanied by suppression of the NOD1/RIP2/NF-kB signaling pathway in both the intestine and pancreas of the two intervention groups. Taken together, these results suggested that the gut microbiota-DAP-NOD1/RIP2 signaling pathway might play a critical role in the progression of AP and that SAP could be alleviated via intervention in the signaling pathway. Our work provides new potential early warning indicators of SAP and targets for intervention.
Assuntos
Microbioma Gastrointestinal , Pancreatite , Doença Aguda , Animais , Ácido Diaminopimélico/química , Ácido Diaminopimélico/metabolismo , Ácido Diaminopimélico/farmacologia , Microbioma Gastrointestinal/fisiologia , NF-kappa B/metabolismo , Neomicina , Proteína Adaptadora de Sinalização NOD1/genética , Proteína Adaptadora de Sinalização NOD1/metabolismo , Ratos , Transdução de SinaisRESUMO
BACKGROUND: Neuroendocrine tumors (NETs) arise from neuroendocrine cells and are extremely rare in the biliary tract. Currently, there are no guidelines for the diagnosis and treatment of biliary NETs. We presented a case with NETs G1 of the hilar bile duct and the challenges for her treatment. CASE PRESENTATION: A 24-year-old woman was presented to our department with painless jaundice and pruritus, and the preoperative diagnosis was Bismuth type II hilar cholangiocarcinoma. She underwent Roux-en-Y hepaticojejunostomy with excision of the extrahepatic biliary tree and radical lymphadenectomy. Unexpectedly, postoperative pathological and immunohistochemical examination indicated a perihilar bile duct NETs G1 with the microscopic invasion of the resected right hepatic duct. Then the patient received 3 cycles of adjuvant chemotherapy (Gemcitabine and tegafur-gimeracil-oteracil potassium capsule). At present, this patient has been following up for 24 months without recurrence or disease progression. CONCLUSION: We know little of biliary NETs because of its rarity. There are currently no guidelines for the diagnosis and treatment of biliary NETs. We reported a case of perihilar bile duct NETs G1 with R1 resection, as far as we know this is the first report. More information about biliary NETs should be registered.
Assuntos
Neoplasias dos Ductos Biliares , Ductos Biliares Extra-Hepáticos , Tumor de Klatskin , Tumores Neuroendócrinos , Adulto , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos , Feminino , Humanos , Tumores Neuroendócrinos/cirurgia , Adulto JovemRESUMO
INTRODUCTION: It is widely accepted that inflammatory responses play a key role in acute pancreatitis (AP). We conducted a systematic review and meta-analysis to determine the effect of QingYi decoction on inflammatory markers. METHODS: The PubMed, EMBASE, Cochrane, CNKI, CBM, and WANFGANG databases were searched for randomized controlled trials published before December 2019. Thirty-nine eligible studies were included in the meta-analysis. The quality of the included studies was assessed using the Cochrane Collaboration risk of bias tool. The standardized mean differences (SMDs) with corresponding 95% CIs were examined for inflammatory markers. The chi-square test and I2 statistic were used to assess heterogeneity. We assessed publication bias by Begg's test, Egger's test, and the trim and fill method. In addition, a meta-regression, sensitivity analysis, subgroup analysis, and cumulative meta-analysis were performed to assess the effects of confounding factors. The quality of evidence was evaluated by the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. RESULTS: The pooled effect estimate indicated that QingYi decoction treatment significantly reduced the levels of pro-inflammatory IL-6 (SMD = -3.33; 95% CI, -4.17, -2.50; p < 0.001; I2: 97.9%), IL-8 (SMD = -1.55; 95% CI, -2.03, -1.07; p < 0.001; I2: 96.1%), TNF-α (SMD = -1.04; 95% CI, -1.37, -0.72; p < 0.001; I2: 93.9%), IL-1 (SMD = -2.05; 95% CI, -3.21, -0.90; p < 0.001; I2: 93.4%), and IL-1ß (SMD = -1.31; 95% CI, -2.42, -0.21; p < 0.001; I2: 89.8%) and elevated the levels of anti-inflammatory IL-10 (SMD = 0.99; 95% CI, 0.60, 1.38; p < 0.001; I2: 91.1%) among patients with AP. CONCLUSION: The current review and meta-analysis suggest that the therapeutic effect of QingYi decoction may be related to its anti-inflammatory properties. Due to the high heterogeneity across the included studies, additional large-scale and rigorously designed studies are needed to confirm the conclusions of this study.
Assuntos
Pancreatite , Doença Aguda , Anti-Inflamatórios , Biomarcadores , Medicamentos de Ervas Chinesas , Humanos , Pancreatite/tratamento farmacológicoRESUMO
Long non-coding RNAs (lncRNAs) contribute to disease pathogenesis and drug treatment effects. Both emodin and dexamethasone (DEX) have been used for treating severe acute pancreatitis-associated acute lung injury (SAP-ALI). However, lncRNA regulation networks related to SAP-ALI pathogenesis and drug treatment are unreported. In this study, lncRNAs and mRNAs in the lung tissue of SAP-ALI and control rats, with or without drug treatment (emodin or DEX), were assessed by RNA sequencing. Results showed both emodin and DEX were therapeutic for SAP-ALI and that mRNA and lncRNA levels differed between untreated and treated SAP-ALI rats. Gene expression profile relationships for emodin-treated and control rats were higher than DEX-treated and -untreated animals. By comparison of control and SAP-ALI animals, more up-regulated than down-regulated mRNAs and lncRNAs were observed with emodin treatment. For DEX treatment, more down-regulated than up-regulated mRNAs and lncRNAs were observed. Functional analysis demonstrated both up-regulated mRNA and co-expressed genes with up-regulated lncRNAs were enriched in inflammatory and immune response pathways. Further, emodin-associated lncRNAs and mRNAs co-expressed modules were different from those associated with DEX. Quantitative polymerase chain reaction demonstrates selected lncRNA and mRNA co-expressed modules were different in the lung tissue of emodin- and DEX-treated rats. Also, emodin had different effects compared with DEX on co-expression network of lncRNAs Rn60_7_1164.1 and AABR07062477.2 for the blue lncRNA module and Nrp1 for the green mRNA module. In conclusion, this study provides evidence that emodin may be a suitable alternative or complementary medicine for treating SAP-ALI.
Assuntos
Lesão Pulmonar Aguda/etiologia , Emodina/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Pancreatite/complicações , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Animais , Biomarcadores , Biópsia , Biologia Computacional/métodos , Citocinas/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Ontologia Genética , Mediadores da Inflamação/metabolismo , Masculino , RatosRESUMO
Acute biliary pancreatitis (ABP) is a potentially life-threatening disease that is induced by the common bile duct (CBD) sludge or stones. This study aimed to investigate protective effects of Qingyi Decoction (QYT) on deoxycholic-acid-sodium salt (DCA) induced ABP in rats. Gpbar1 is a G-protein coupled receptor that can be activated by DCA. Both Gpbar1 overexpression vector and Gpbar1 RNAi were constructed and transfected into ABP cell models. Functional assays reveal that DCA significantly induced AR42J apoptosis and triggered Gpbar1 expression. Gpbar1 significantly activated caspase 8 and caspase 9 as compared to LV5-NC and LV3-NC (p<0.05). Gpbar1 significantly triggered apoptosis associated inflammatory factors as compared to LV5-NC and LV3-NC (p<0.05). Gpbar1 significantly induced calcium flux as compared to LV5-NC and LV3-NC (p<0.05). Gpbar1 up-regulated caspases and inflammatory factors in DCA treated pancreatic acinar cells. QYT reversed DCA induced apoptosis and inflammatory response. QYT significantly reduced Gpbar1 levels compared to no-QTY treated cells (p<0.05). In conclusion, QYT protects against DCA induced pancreatic acinar cell damage in ABP by inhibiting Gpbar1/NF-kB/p-RIP signaling pathway.
Assuntos
Medicamentos de Ervas Chinesas/farmacologia , NF-kappa B/metabolismo , Pancreatite/tratamento farmacológico , Receptores Acoplados a Proteínas G/metabolismo , Doença Aguda , Animais , Apoptose , Caspase 8/metabolismo , Caspase 9/metabolismo , Linhagem Celular , Regulação Enzimológica da Expressão Gênica , Inflamação , Pancreatite/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de SinaisRESUMO
AIM: To investigate the effect of Qingyi decoction on the expression of secreted phospholipase A2 (sPLA2) in intestinal barrier injury. METHODS: Fifty healthy Sprague-Dawley rats were randomly divided into control, severe acute pancreatitis (SAP), Qingyi decoction-treated (QYT), dexamethasone-treated (DEX), and verapamil-treated (VER) groups. The SAP model was induced by retrograde infusion of 1.5% sodium deoxycholate into the biliopancreatic duct of the rats. All rats were sacrificed 24 h post-SAP induction. Arterial blood, intestine, and pancreas from each rat were harvested for investigations. The levels of serum amylase (AMY) and diamine oxidase (DAO) were determined using biochemical methods, and serum tumor necrosis factor (TNF)-α level was measured by an enzyme linked immunosorbent assay. Pathologic changes in the harvested tissues were investigated by microscopic examination of hematoxylin and eosin-stained tissue sections. The expressions of sPLA2 at mRNA and protein levels were detected by reverse transcriptase PCR and Western blot, respectively. A terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay was used to investigate apoptosis of epithelial cells in the intestinal tissues. RESULTS: Compared to the control group, the expression of sPLA2 at both the mRNA and protein levels increased significantly in the SAP group (0.36 ± 0.13 vs 0.90 ± 0.38, and 0.16 ± 0.05 vs 0.64 ± 0.05, respectively; Ps < 0.01). The levels of AMY, TNF-α and DAO in serum were also significantly increased (917 ± 62 U/L vs 6870 ± 810 U/L, 59.7 ± 14.3 ng/L vs 180.5 ± 20.1 ng/L, and 10.37 ± 2.44 U/L vs 37.89 ± 5.86 U/L, respectively; Ps < 0.01). The apoptosis index of intestinal epithelial cells also differed significantly between the SAP and control rats (0.05 ± 0.02 vs 0.26 ± 0.06; P < 0.01). The serum levels of DAO and TNF-α, and the intestinal apoptosis index significantly correlated with sPLA2 expression in the intestine (r = 0.895, 0.893 and 0.926, respectively; Ps < 0.05). The levels of sPLA2, AMY, TNF-α, and DAO in the QYT, VER, and DEX groups were all decreased compared with the SAP group, but not the control group. Qingyi decoction intervention, however, gave the most therapeutic effect against intestinal barrier damage, although the onset of its therapeutic effect was slower. CONCLUSION: Qingyi decoction ameliorates acute pancreatitis-induced intestinal barrier injury by inhibiting the overexpression of intestinal sPLA2. This mechanism may be similar to that of verapamil.
Assuntos
Anti-Inflamatórios/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Mucosa Intestinal/efeitos dos fármacos , Pancreatite/tratamento farmacológico , Doença Aguda , Amina Oxidase (contendo Cobre)/sangue , Amilases/sangue , Animais , Apoptose/efeitos dos fármacos , Ácido Desoxicólico , Dexametasona/farmacologia , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Regulação Enzimológica da Expressão Gênica , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Pancreatite/induzido quimicamente , Pancreatite/genética , Pancreatite/metabolismo , Pancreatite/patologia , Fosfolipases A2 Secretórias/genética , Fosfolipases A2 Secretórias/metabolismo , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Índice de Gravidade de Doença , Fator de Necrose Tumoral alfa/sangue , Verapamil/farmacologiaRESUMO
Despite numerous studies, there is no definitive evidence that high-frequency electromagnetic field (EMF) exposure is a risk to human health. To the contrary, this report presents the first evidence that long-term EMF exposure directly associated with cell phone use (918 MHz; 0.25 w/kg) provides cognitive benefits. Both cognitive-protective and cognitive-enhancing effects of EMF exposure were discovered for both normal mice and transgenic mice destined to develop Alzheimer's-like cognitive impairment. The cognitive interference task utilized in this study was designed from, and measure-for-measure analogous to, a human cognitive interference task. In Alzheimer's disease mice, long-term EMF exposure reduced brain amyloid-beta (Abeta) deposition through Abeta anti-aggregation actions and increased brain temperature during exposure periods. Several inter-related mechanisms of EMF action are proposed, including increased Abeta clearance from the brains of Alzheimer's disease mice, increased neuronal activity, and increased cerebral blood flow. Although caution should be taken in extrapolating these mouse studies to humans, we conclude that EMF exposure may represent a non-invasive, non-pharmacologic therapeutic against Alzheimer's disease and an effective memory-enhancing approach in general.
Assuntos
Doença de Alzheimer/terapia , Transtornos Cognitivos/prevenção & controle , Modelos Animais de Doenças , Magnetoterapia/métodos , Doença de Alzheimer/complicações , Doença de Alzheimer/psicologia , Animais , Transtornos Cognitivos/complicações , Transtornos Cognitivos/psicologia , Campos Eletromagnéticos , Camundongos , Camundongos TransgênicosRESUMO
The neurohormone melatonin has been reported to exert anti-beta-amyloid aggregation, antioxidant, and anti-inflammatory actions in various in vitro and animal models. To comprehensively determine the potential for long-term melatonin treatment to protect Alzheimer's transgenic mice against cognitive impairment and development of beta-amyloid (Abeta) neuropathology, we administered melatonin (100 mg/L drinking water) to APP + PS1 double transgenic (Tg) mice from 2-2.5 months of age to their killing at age 7.5 months. A comprehensive behavioral battery administered during the final 6 weeks of treatment revealed that Tg mice given melatonin were protected from cognitive impairment in a variety of tasks of working memory, spatial reference learning/memory, and basic mnemonic function; Tg control mice remained impaired in all of these cognitive tasks/domains. Immunoreactive Abeta deposition was significantly reduced in hippocampus (43%) and entorhinal cortex (37%) of melatonin-treated Tg mice. Although soluble and oligomeric forms of Abeta1-40 and 1-42 were unchanged in the hippocampus and cortex of the same melatonin-treated Tg mice, their plasma Abeta levels were elevated. These Abeta results, together with our concurrent demonstration that melatonin suppresses Abeta aggregation in brain homogenates, are consistent with a melatonin-facilitated removal of Abeta from the brain. Inflammatory cytokines such as tumor necrosis factor (TNF)-alpha were decreased in hippocampus (but not plasma) of Tg+ melatonin mice. Finally, the cortical mRNA expression of three antioxidant enzymes (SOD-1, glutathione peroxidase, and catalase) was significantly reduced to non-Tg levels by long-term melatonin treatment in Tg mice. Thus, melatonin's cognitive benefits could involve its anti-Abeta aggregation, anti-inflammatory, and/or antioxidant properties. Our findings provide support for long-term melatonin therapy as a primary or complementary strategy for abating the progression of Alzheimer disease.