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1.
Redox Biol ; 70: 103057, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38325196

RESUMO

Neuroinflammation and oxidative stress play a crucial role in the pathogenesis of neurodegenerative diseases, including Alzheimer's disease. The triggering receptor expressed on myeloid cells 2 (TREM2), highly expressed by microglia in the central nervous system (CNS), can modulate neuroinflammatory responses. Currently, there are no approved drugs specifically targeting TREM2 for CNS diseases. Aspidosperma alkaloids have shown potential as anti-inflammatory and neuroprotective agents. This study aimed to elucidate the potential therapeutic effect of Hecubine, a natural aspidosperma-type alkaloid, as a TREM2 activator in lipopolysaccharide (LPS)-stimulated neuroinflammation in in vitro and in vivo models. In this study, molecular docking and cellular thermal shift assay (CTSA) were employed to investigate the interaction between Hecubine and TREM2. Enzyme-linked immunosorbent assay (ELISA), quantitative PCR, immunofluorescence, Western blotting, and shRNA gene knockdown were used to assess the anti-neuroinflammatory and antioxidant effects of Hecubine in microglial cells and zebrafish. Our results revealed that Hecubine directly interacted with TREM2, leading to its activation. Knockdown of TREM2 mRNA expression significantly abolished the anti-inflammatory and antioxidant effects of Hecubine on LPS-stimulated proinflammatory mediators (NO, TNF-α, IL-6, and IL-1ß) and oxidative stress in microglia cells. Furthermore, Hecubine upregulated Nrf2 expression levels while downregulating TLR4 signaling expression levels both in vivo and in vitro. Silencing TREM2 upregulated TLR4 and downregulated Nrf2 signaling pathways, mimicking the effect of Hecubine, further supporting TREM2 as the drug target by which Hecubine inhibits neuroinflammation. In conclusion, this is the first study to identify a small molecule, namely Hecubine directly targeting TREM2 to mediate anti-neuroinflammation and anti-oxidative effects, which serves as a potential therapeutic agent for the treatment of neural inflammation-associated CNS diseases.


Assuntos
Doença de Alzheimer , Aspidosperma , Animais , Lipopolissacarídeos/toxicidade , Aspidosperma/metabolismo , Doenças Neuroinflamatórias , Receptor 4 Toll-Like/metabolismo , Fator 2 Relacionado a NF-E2 , Antioxidantes/uso terapêutico , Simulação de Acoplamento Molecular , Peixe-Zebra/metabolismo , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/genética , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Doença de Alzheimer/metabolismo
2.
Clin Kidney J ; 16(12): 2605-2613, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38046019

RESUMO

Background: Membranous nephropathy (MN) is the leading cause of adult-onset nephrotic syndrome, with primary MN of unclear cause accounting for 80% of cases. Retrospective clinical research reported that MN occurring in rheumatoid arthritis (RA) and ankylosing spondylitis (AS) patients was triggered by nephrotoxic drugs or of unknown cause. However, whether RA or AS itself increases the risk of developing MN is unknown. Methods: We conducted mendelian randomization (MR) analysis to evaluate the causal effects of RA or AS on MN using genome-wide association study (GWAS) statistics. The inverse variance weighted (IVW) method was the primary analysis, and several supplementary analyses and sensitivity analyses were performed to test the causal estimates. Results: We obtained 30 valid instrumental variables (IVs) of RA and 16 valid IVs of AS from large-scale open-access GWASs. The genetically predicted RA significantly increased the risk of MN [IVW odds ratios (OR) = 1.327, 95% confidence interval (CI) = (1.124, 1.565), P = 8.051 × 10-4]. Three supplementary MR analyses provided the consistent positive causal effect of RA on MN (all P < 0.05). No horizontal pleiotropy was detected by MR Egger intercept analysis (P = 0.411). However, the genetically predicted AS had no causal effect on MN by IVW and supplementary analysis (all P > 0.05). Conclusions: Genetically predicted RA could increase the risk of MN, but genetically predicted AS was not associated with MN. Screening for kidney involvement in RA patients should be noted, and active treatment of RA will reduce the public health burden of MN.

3.
Ren Fail ; 45(1): 2178821, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36794437

RESUMO

Contrast-induced acute kidney injury (CI-AKI), which occurs after the use of iodinated contrast media, has become the third leading cause of hospital-acquired acute kidney injury (AKI). It is associated with prolonged hospitalization and increased risks of end-stage renal disease and mortality. The pathogenesis of CI-AKI is unclear and effective treatments are lacking. By comparing different post-nephrectomy times and dehydration times, we constructed a new, short-course CI-AKI model using dehydration for 24 h two weeks after unilateral nephrectomy. We found that the low-osmolality contrast media iohexol caused more severe renal function decline, renal morphological damage, and mitochondrial ultrastructural alterations compared to the iso-osmolality contrast media iodixanol. The shotgun proteomics based on Tandem Mass Tag (TMT) was used to conduct proteomics research on renal tissue in the new CI-AKI model, and 604 distinct proteins were identified, mainly involving complement and coagulation cascade, COVID-19, PPAR signalling pathway, mineral absorption, cholesterol metabolism, ferroptosis, staphylococcus aureus infection, systemic lupus erythematosus, folate biosynthesis, and proximal tubule bicarbonate reclamation. Then, using parallel reaction monitoring (PRM), we validate 16 candidate proteins, of which five were novel candidates (Serpina1, Apoa1, F2, Plg, Hrg) previously unrelated to AKI and associated with an acute response as well as fibrinolysis. The pathway analysis and 16 candidate proteins may help to discover new mechanisms in the pathogenesis of CI-AKI, allowing for early diagnosis and outcome prediction.


Assuntos
Injúria Renal Aguda , Proteômica , Animais , Ratos , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/diagnóstico , Meios de Contraste/efeitos adversos , Desidratação/patologia , Rim
4.
Front Med (Lausanne) ; 9: 892473, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36045922

RESUMO

Background and Objectives: Acute kidney injury (AKI) that results from ischemia is a common clinical syndrome and correlates with high morbidity and mortality among hospitalized patients. However, a clinical tool to predict mortality risk of ischemic AKI is not available. In this study, we aimed to develop and validate models to predict the 30-day and 1-year mortality risk of hospitalized patients with ischemic AKI. Methods: A total of 1,836 admissions with ischemic AKI were recruited from 277,898 inpatients admitted to three affiliated tertiary general hospitals of Central South University in China between January 2015 and December 2015. Patients in the final analysis were followed up for 1 year. Study patients were randomly divided in a 7:3 ratio to form the training cohort and validation cohort. Multivariable regression analyses were used for developing mortality prediction models. Results: Hepatorenal syndrome, shock, central nervous system failure, Charlson comorbidity index (≥2 points), mechanical ventilation, renal function at discharge were independent risk factors for 30-day mortality after ischemic AKI, while malignancy, sepsis, heart failure, liver failure, Charlson comorbidity index (≥2 points), mechanical ventilation, and renal function at discharge were predictors for 1-year mortality. The area under the receiver operating characteristic curves (AUROCs) of 30-day prediction model were 0.878 (95% confidence interval (CI): 0.849-0.908) in the training cohort and 0.867 (95% CI: 0.820-0.913) in the validation cohort. The AUROCs of the 1-year mortality prediction in the training and validation cohort were 0.803 (95% CI: 0.772-0.834) and 0.788 (95% CI: 0.741-0.835), respectively. Conclusion: Our easily applied prediction models can effectively identify individuals at high mortality risk within 30 days or 1 year in hospitalized patients with ischemic AKI. It can guide the optimal clinical management to minimize mortality after an episode of ischemic AKI.

5.
Front Pediatr ; 10: 885055, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35676902

RESUMO

Objective: The epidemiology and outcomes of acute kidney disease (AKD) after acute kidney injury (AKI) in hospitalized children are poorly described. The aim of this study is to investigate the prevalence, predictive factors, and clinical outcomes of AKD in hospitalized children with AKI. Methods: Children (1 month-18 years) with AKI during hospitalization in the Second Xiangya Hospital from January 2015 to December 2020 were identified. AKD was defined based on the consensus report of the Acute Disease Quality Initiative 16 workgroup. The endpoints include adverse outcomes in 30 and 90 days. Multivariable logistic regression analyses were used to estimate the odds ratio of 30- and 90-day adverse outcomes associated with AKD and identify the risk factors of AKD. Results: AKD was developed in 42.3% (419/990) of the study patients, with 186 in AKD stage 1, 107 in AKD stage 2, and 126 in AKD stage 3. Pediatric patients with AKD stages 2-3 had significantly higher rates of developing 30- and 90-day adverse outcomes than those with AKD stage 0 and 1. The adjusted odds ratio of AKD stage 2-3 was 12.18 (95% confidence interval (CI), 7.38 - 20.09) for 30-day adverse outcomes and decreased to 2.49 (95% CI, 1.26 - 4.91) for 90-day adverse outcomes. AKI stages 2 and 3, as well as glomerulonephritis, were the only predictive factors for AKD stage 2-3. Conclusion: AKD is frequent among hospitalized pediatric AKI patients. AKD stage 2-3 represents a high-risk subpopulation among pediatric AKI survivors and is independently associated with 30- and 90-day adverse outcomes. Awareness of the potential risks associated with AKD stage 2-3 and its risk factors may help improve outcomes through careful monitoring and timely intervention.

6.
Neurotox Res ; 39(4): 1323-1337, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33999357

RESUMO

The present study aimed to evaluate the neuroprotective effects and underlying mechanisms of pinocembrin-7-methylether (PME), a natural bioflavonoid, in 6-hydroxydopamine (6-OHDA)-induced models of Parkinson's disease in vivo and in vitro. First, we found that PME decreased apoptosis in 6-OHDA-intoxicated SH-SY5Y cells. PME also blocked several 6-OHDA-induced mitochondrial apoptotic cascades, including loss of mitochondrial membrane potential, caspase 3 and PARP activation, and a decrease in the Bcl-2/Bax ratio. Also, PME suppressed 6-OHDA-induced oxidative stress while increasing antioxidant enzymatic activity. Further investigations indicated that PME significantly enhanced nuclear accumulation of Nrf2, improved ARE promoter activity, and upregulated HO-1 and NQO1 expression levels. In addition, siRNA-mediated Nrf2 knockdown abolished PME-induced anti-oxidative and anti-apoptotic effects. Interestingly, we found that PME promoted phosphorylation of AKT and ERK, whereas pharmacological inhibition of AKT or ERK pathways diminished PME-induced Nrf2 activation and protective actions. Moreover, PME attenuated 6-OHDA-induced loss of dopaminergic neurons and ameliorated locomotor deficiency in zebrafish, supporting the neuroprotective actions of PME in vivo. In summary, we found that PME conferred neuroprotection against 6-OHDA-induced neurotoxicity in PD models in vivo and in vitro. Taken together, our findings suggest that activation of Nrf2/ARE/HO-1 signaling cascades contributes to PME-induced anti-oxidative and neuroprotective actions, which are at least partially mediated by AKT and ERK pathways.


Assuntos
Flavanonas/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/biossíntese , Fármacos Neuroprotetores/farmacologia , Oxidopamina/toxicidade , Proteínas Proto-Oncogênicas c-akt/biossíntese , Proteínas de Peixe-Zebra/biossíntese , Animais , Linhagem Celular Tumoral , Fragmentação do DNA/efeitos dos fármacos , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Relação Dose-Resposta a Droga , Flavanonas/uso terapêutico , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , Fármacos Neuroprotetores/uso terapêutico , Peixe-Zebra
7.
Biomed Pharmacother ; 97: 423-428, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29091892

RESUMO

The pathological characteristics of atherosclerosis (AS) include lipid accumulation, fibrosis formation and atherosclerotic plaque produced in artery intima, which leads to vascular sclerosis, lumen stenosis and irritates the ischemic changes of corresponding organs. Endothelial dysfunction was closely associated with AS. Nitric oxide (NO) is a multifunctional signaling molecule involved in the maintenance of metabolic and cardiovascular homeostasis. NO is also a potent endogenous vasodilator and enters for the key processes that suppresses the formation vascular lesion even AS. NO bioavailability indicates the production and utilization of endothelial NO in organisms, its decrease is related to oxidative stress, lipid infiltration, the expressions of some inflammatory factors and the alteration of vascular tone, which plays an important role in endothelial dysfunction. The enhancement of arginase activity and the increase in asymmetric dimethylarginine and hyperhomocysteinemia levels all contribute to AS by intervening NO bioavailability in human beings. Diabetes mellitus, obesity, chronic kidney disease and smoking, etc., also participate in AS by influencing NO bioavailability and NO level. Here, we reviewed the relationship between NO bioavailability and AS according the newest literatures.


Assuntos
Aterosclerose/metabolismo , Endotélio Vascular/metabolismo , Óxido Nítrico/metabolismo , Animais , Arginina/análogos & derivados , Arginina/metabolismo , Aterosclerose/epidemiologia , Disponibilidade Biológica , Doenças Cardiovasculares/metabolismo , Humanos , Obesidade/epidemiologia , Obesidade/metabolismo , Estresse Oxidativo/fisiologia , Fumar/efeitos adversos , Fumar/epidemiologia , Fumar/metabolismo , Vasodilatação/fisiologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-28424738

RESUMO

Li-Fei-Xiao-Yan prescription (LFXY) has been clinically used in China to treat inflammatory and infectious diseases including inflammatory lung diseases. The present study was aimed at evaluating the potential therapeutic effects and potential mechanisms of LFXY in a murine model of lipopolysaccharide- (LPS-) induced acute lung injury (ALI). In this study, the mice were orally pretreated with LFXY or dexamethasone (positive drug) before the intratracheal instillation of LPS. Our data indicated that pretreatment with LFXY enhanced the survival rate of ALI mice, reversed pulmonary edema and permeability, improved LPS-induced lung histopathology impairment, suppressed the excessive inflammatory responses via decreasing the expression of proinflammatory cytokines (TNF-α, IL-1ß, and IL-6) and chemokine (MIP-2) and inhibiting inflammatory cells migration, and repressed oxidative stress through the inhibition of MPO and MDA contents and the upregulation of antioxidants (SOD and GSH) activities. Mechanistically, treatment with LFXY significantly prevented LPS-induced TLR4 expression and NF-κB (p65) phosphorylation. Overall, the present study suggests that LFXY protected mice from acute lung injury induced by LPS via inhibition of TLR4/NF-κB p65 activation and upregulation of antioxidative enzymes and it may be a potential preventive and therapeutic agent for ALI in the clinical setting.

9.
Mol Med Rep ; 15(6): 4239-4246, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28440419

RESUMO

Osthole is the primary active component of a number of herbal plants such as the Cnidium monnieri fruit. In traditional Chinese herb medicine, osthole is commonly used in combination with borneol to obtain improved pharmacological effects. The aim of the present study was to investigate the effect of borneol enantiomers on the pharmacokinetics of osthole. An appropriate high­performance liquid chromatography (HPLC) method was applied to determine the concentrations of osthole in plasma. Following oral administration of osthole alone or combined with borneol in rats, blood samples were collected and analyzed by HPLC. The results demonstrated that there were statistically significant differences in the pharmacokinetic parameters of osthole between osthole administration alone and co­administration with borneol. When combined with synthetic borneol, the AUC0­t, AUC0­∞ and Cmax of osthole increased by 48.153, 104.708 and 92.630%, respectively, while the CL/F decreased by 51.251%. When combined with (+)­borneol, the AUC0­t, AUC0­∞ and Cmax of osthole were increased by 61.561, 78.167, and 51.769%, respectively, while the CL/F decreased by 44.174% (P<0.01). In addition, when combined with (­)­borneol, the AUC0­t, AUC0­∞ and Cmax of osthole increased by 115.856, 167.786 and 271.289%, respectively, while the CL/F decreased by 60.686% (P<0.01). These results indicated that borneol may enhance gastrointestinal absorption and inhibit the metabolism of osthole. In addition, the promotional effect of (­)­borneol on the pharmacokinetic parameters of osthole was greater than that of (+)­borneol.


Assuntos
Canfanos/farmacologia , Cumarínicos/farmacocinética , Administração Oral , Animais , Área Sob a Curva , Medicamentos de Ervas Chinesas/farmacocinética , Masculino , Medicina Tradicional Chinesa/métodos , Ratos , Ratos Sprague-Dawley
10.
BMC Complement Altern Med ; 17(1): 185, 2017 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-28359333

RESUMO

BACKGROUND: Xiao'er Qixingcha (EXQ) has been extensively applied to relieve dyspepsia and constipation in children for hundreds of years in China. However, the therapeutic mechanism underlying its efficacy remained to be defined. The present study aimed to clarify the possible laxative and immune-regulating effects of EXQ on two models of experimental constipation in mice, which mimicked the pediatric constipation caused by high-heat and high-protein diet (HHPD). METHODS: The two models of constipated mice were induced by HHPD or HHPD + atropine respectively. To investigate the laxative and immune-regulating activities of EXQ, animals were treated with three doses of EXQ (0.75, 1.5 and 3 g/kg) for 7 consecutive days. The fecal output parameters (number and weight), weight of intestinal content and, the thymus and spleen indexes were measured. The levels of sIgA, IL-10, TNF-α and LPS in colon and serum were determined by ELISA. Furthermore, the pathological changes of colon tissue were examined after routine H&E staining. RESULTS: Both HHPD and HHPD + atropine treatments obviously inhibited the fecal output and reduced the colonic sIgA, prominently increased the levels of IL-10 and TNF-α in colonic tissue and elevated the contents of LPS in serum and colonic tissues. In contrast, oral administration of EXQ significantly improved the feces characters and dose-dependently decreased the intestinal changes in both models. In HHPD model test, EXQ efficaciously boosted the sIgA level in a dose-dependent manner, significantly elicited decreases in TNF-α and IL-10 levels, and evidently decreased the spleen and thymus indexes. In HHPD + atropine model test, EXQ treatment reversed the pathological changes by not only dramatically decreasing the spleen index and the levels of LPS and IL-10, but also markedly elevating the thymus index. Furthermore, microscopic observation revealed that EXQ treatment maintained the integrity of colonic mucosa, and protected the colonic tissues from inflammation in the both models. CONCLUSIONS: EXQ exhibited prominent laxative activity and effectively protected the colonic mucosal barrier in two models of constipated mice, of which the mechanism might be closely associated with its propulsive and immune-regulating properties. The current results not only validated the rationale for the clinical application of EXQ in pediatric constipation related symptoms, but also threw new light on the immune-inflammatory responses accompanied with chronic constipation pathology.


Assuntos
Constipação Intestinal/tratamento farmacológico , Constipação Intestinal/imunologia , Medicamentos de Ervas Chinesas/administração & dosagem , Fatores Imunológicos/administração & dosagem , Laxantes/administração & dosagem , Animais , China , Colo/efeitos dos fármacos , Colo/imunologia , Citocinas/imunologia , Dieta , Proteínas Alimentares/efeitos adversos , Proteínas Alimentares/análise , Temperatura Alta , Humanos , Intestinos , Masculino , Camundongos , Baço/efeitos dos fármacos , Baço/imunologia , Timo/efeitos dos fármacos , Timo/imunologia
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(3): 724-8, 2016 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-27400514

RESUMO

As one of the necessary steps for data processing of Raman spectroscopy, baseline correction is commonly used to eliminate the interference of fluorescence spectra. The traditional baseline correction algorithm based on polynomial fitting is simple and easy to implement, but its flexibility is poor due to the uncertain fitting order. In this paper, instead of using polynomial fitting, non-uniform B-spline is proposed to overcome the shortcomings of the traditional method. Based on the advantages of the traditional algorithm, the node vector of non-uniform B-spline is fixed adaptively using the peak position of the original Raman spectrum, and then the baseline is fitted with the fixed order. In order to verify this algorithm, the Raman spectra of parathion-methyl and colza oil are detected and their baselines are corrected using this algorithm, the result is made comparison with two other baseline correction algorithms. The experimental results show that the effect of baseline correction is improved by using this algorithm with a fixed fitting order and less parameters, and there is no over or under fitting phenomenon. Therefore, non-uniform B-spline is proved to be an effective baseline correction algorithm of Raman spectroscopy.

12.
Exp Gerontol ; 77: 76-86, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26929999

RESUMO

Pogostone, a chemical constituent of patchouli oil, has been confirmed to possess favorable anti-inflammatory property. In the present study, we investigated the possible anti-photoaging potential of pogostone and the underlying mechanism against UV-induced skin damage in mice. The macroscopic and histopathological lesions were significantly ameliorated by pretreatment of pogostone as compared to the VC group. Furthermore, topical application of pogostone markedly increased the activities of the antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and observably decreased malonaldehyde (MDA) level. Analysis of inflammatory cytokines showed obvious down-regulation of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-1ß (IL-1ß) and cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2) in the pogostone groups. In addition, pogostone pretreatment evidently inhibited the abnormal expression of matrix metalloproteinases (MMP-1 and MMP-3). Taken together, pogostone exhibited prominent photo-protective activity mainly by its antioxidative and anti-inflammatory properties, promising it as an effective alternative pharmaceutical therapy for photoaging.


Assuntos
Óleos Voláteis/uso terapêutico , Envelhecimento da Pele/efeitos dos fármacos , Pele/patologia , Animais , Antioxidantes/metabolismo , Citocinas/metabolismo , Feminino , Hiperplasia/tratamento farmacológico , Malondialdeído/metabolismo , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/metabolismo , Camundongos , Óleos Voláteis/farmacologia , Pele/enzimologia , Raios Ultravioleta
13.
Mediators Inflamm ; 2016: 3271451, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26903706

RESUMO

Andrographolide sodium bisulfate (ASB), a water-soluble form made from andrographolide through sulfonating reaction, is an antioxidant and anti-inflammatory drug; however, the antiphotoaging effect of ASB has still not been revealed. Oxidative stress and inflammation are known to be responsible for ultraviolet (UV) irradiation induced skin damage and consequently premature aging. In this study, we aimed at examining the effect of ASB on UV-induced skin photoaging of mice by physiological and histological analysis of skin and examination of skin antioxidant enzymes and immunity analyses. Results showed that topical administration of ASB suppressed the UV-induced skin thickness, elasticity, wrinkles, and water content, while ASB, especially at dose of 3.6 mg/mouse, increased the skin collagen content by about 53.17%, decreased the epidermal thickness by about 41.38%, and prevented the UV-induced disruption of collagen fibers and elastic fibers. Furthermore, ASB decreased MDA level by about 40.21% and upregulated the activities of SOD and CAT and downregulated the production of IL-1ß, IL-6, IL-10, and TNF-α in UV-irradiated mice. Our study confirmed the protective effect of ASB against UV-induced photoaging and initially indicated that this effect can be attributed to its antioxidant and anti-inflammatory activities in vivo, suggesting that ASB may be a potential antiphotoaging agent.


Assuntos
Diterpenos/farmacologia , Inflamação/prevenção & controle , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Animais , Feminino , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Baço/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Timo/metabolismo
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(12): 4082-7, 2016 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-30256578

RESUMO

To improve time resolution of the Raman measurement system, we need to adopt short scanning time. In this case, the weak Raman signal with vibrational spectrum of the molecular structure is easily to be buried by the high background noise, which influences the further analysis seriously. So it is necessary to de-noise the raw Raman signals. Conventional methods manage to de-noise signal by means of smoothing or averaging based on the difference between signal and noise in frequency characteristic or statistical features. They are commonly applied in the situation where the background noise is not so strong, and cannot give satisfactory results to the Raman signals with low signal-to-noise ratio. In this paper, the algorithm proposed detects peak positions and get peak half-width based on wavelet transform, and then reconstructs the Raman signals by least square fitting algorithm with characteristic parameters obtained, which extracts the useful signal from high background noise efficiently. In the simulation, the Raman curve fitted by the proposed algorithm was smooth, and the peak positions obtained were accurate, so the signal-to-noise ratio improved significantly. In the experiment, we adopted this algorithm to de-noise the tested Raman signal of Cefuroxime Axetil Tablets and Roxithromycin, respectively. The peak positions, peak half-width and amplitude were obtained and proved to be accurate. Therefore, the useful pure Raman signal could be recovered from the high background noise efficiently by the proposed algorithm, which improved the time resolution of Raman system. Both the simulation and the experiment showed that the proposed method could be easily performed with only a few parameters. Comparing with conventional methods, it could achieve satisfactory results under high background noise and provide accurate and reliable information for further analysis.

15.
BMC Complement Altern Med ; 15: 238, 2015 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-26179287

RESUMO

BACKGROUND: The inhibitory effect of andrographolide sodium bisulphite (ASB) on jack bean urease (JBU) and Helicobacter pylori urease (HPU) was performed to elucidate the inhibitory potency, kinetics and mechanism of inhibition in 20 mM phosphate buffer, pH 7.0, 2 mM EDTA, 25 °C. METHODS: The ammonia formations, indicator of urease activity, were examined using modified spectrophotometric Berthelot (phenol-hypochlorite) method. The inhibitory effect of ASB was characterized with IC50 values. Lineweaver-Burk and Dixon plots for JBU inhibition of ASB was constructed from the kinetic data. SH-blocking reagents and competitive active site Ni2+ binding inhibitors were employed for mechanism study. Molecular docking technique was used to provide some information on binding conformations as well as confirm the inhibition mode. RESULTS: The IC50 of ASB against JBU and HPU was 3.28±0.13 mM and 3.17±0.34 mM, respectively. The inhibition proved to be competitive and concentration- dependent in a slow-binding progress. The rapid formation of initial ASB-JBU complex with an inhibition constant of Ki=2.86×10(-3) mM was followed by a slow isomerization into the final complex with an overall inhibition constant of Ki*=1.33×10(-4) mM. The protective experiment proved that the urease active site is involved in the binding of ASB. Thiol reagents (L-cysteine and dithiothreithol) strongly protect the enzyme from the loss of enzymatic activity, while boric acid and fluoride show weaker protection, indicating that the active-site sulfhydryl group of JBU was potentially involved in the blocking process. Moreover, inhibition of ASB proved to be reversible since ASB-inactivated JBU could be reactivated by dithiothreitol application. Molecular docking assay suggested that ASB made contacts with the important sulfhydryl group Cys-592 residue and restricted the mobility of the active-site flap. CONCLUSIONS: ASB was a competitive inhibitor targeting thiol groups of urease in a slow-binding manner both reversibly and concentration-dependently, serving as a promising urease inhibitor for the treatment of urease-related diseases.


Assuntos
Diterpenos/farmacologia , Sulfitos/farmacologia , Urease , Canavalia/enzimologia , Cinética , Simulação de Acoplamento Molecular , Urease/química , Urease/efeitos dos fármacos , Urease/metabolismo
16.
ScientificWorldJournal ; 2013: 434151, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24385881

RESUMO

The aim of this study was to investigate the anti-inflammatory property of the ethanol extract of the root and rhizome of Pogostemon cablin (ERP). The anti-inflammatory effect was evaluated using four animal models including xylene-induced mouse ear edema, acetic acid-induced mouse vascular permeability, carrageenan-induced mouse pleurisy, and carrageenan-induced mouse hind paw edema. Results indicated that oral administration of ERP (120, 240, and 480 mg/kg) significantly attenuated xylene-induced ear edema, decreased acetic acid-induced capillary permeability, inhibited carrageenan-induced neutrophils recruitment, and reduced carrageenan-induced paw edema, in a dose-dependent manner. Histopathologically, ERP (480 mg/kg) abated inflammatory response of the edema paw. Preliminary mechanism studies demonstrated that ERP decreased the level of MPO and MDA, increased the activities of anti-oxidant enzymes (SOD, GPx, and GRd), attenuated the productions of TNF-α, IL-1ß, IL-6, PGE2 and NO, and suppressed the activities of COX-2 and iNOS. This work demonstrates that ERP has considerable anti-inflammatory potential, which provided experimental evidences for the traditional application of the root and rhizome of Pogostemon cablin in inflammatory diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Medicamentos de Ervas Chinesas/química , Lamiaceae/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Rizoma/química , Ácido Acético , Administração Oral , Animais , Anti-Inflamatórios/administração & dosagem , Permeabilidade Capilar/efeitos dos fármacos , Carragenina , Cromatografia Líquida de Alta Pressão , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Edema/tratamento farmacológico , Etanol , Malondialdeído/metabolismo , Camundongos , Ativação de Neutrófilo/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , Extratos Vegetais/administração & dosagem , Xilenos
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