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1.
Heliyon ; 10(7): e29060, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38623187

RESUMO

The Spodoptera frugiperda is a notorious pest with a broad host range. It severely damages crops, mainly in areas of the globewhere maize and sorghum are grown. The pest is difficult to control due to its adaptive nature and resistance to several insecticides available in the market. So, an identification of the alternative strategy is the prime important in the present context. Insecticidal activities of cyanobacterial extracts were evaluated in the laboratory as a biocomponent against S. frugiperda. The crude extracts of Nostoc muscorum and Spirulina sp. were prepared by using ethanol, methanol and petroleum ether solvents. Soxhlet apparatus was used for extraction. S. frugiperda larvae in their second instar were given access to fragments of maize leaf that had been treated with various cyanobacterial extracts. The findings displayed that the petroleum ether extract of N. muscorum had the lowest LC50 value of 155.22 ppm, followed by petroleum ether extracts of Spirulina, ethanol extract of N. Muscorum, methanol extract of N. muscorum, ethanol and methanol extract of Spirulina with an LC50 values of 456.02, 710, 780, 1050 and 1070 ppm respectively. Later, the effect of LC50 values on many biological parameters like the larval duration and pupal stages, the percentage of pupation, the weight of the pupal stage, the malformation of the pupal and adult stages, adult emergence percentage, fertility and the longevity of the male and female adult stages of S. frugiperda was examined. The gas chromatography-mass spectrometry (GC-MS) was used to analyse the crude extract to identify the bioactive components that were responsible for the insecticidal properties. The major compounds detected were diethyl phthalate (19.87 %), tetradecane (5.03%), hexadecanoic acid, ethyl ester (4.10 %), dodecane (4.03%), octadecane (3.72%), octadecanoic acid, methyl ester (3.40 %), ethyl oleate (3.11 %), methyl ester. octadecenoic acid (3.04 %), heptadecane (3.04 %) and phytol (3.02 %). The presence of several bioactive chemicals in the cyanobacterial extracts may be the reason for their insecticidal actions, thus it can be used as an alternative and new source to combat fall armyworm and other crop pests.

2.
ACS Omega ; 9(11): 12611-12621, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38524483

RESUMO

PROTAC (proteolysis-targeting chimeras) is a rapidly evolving technology to target undruggable targets. The mechanism by which this happens is when a bifunctional molecule binds to a target protein and also brings an E3 ubiquitin ligase in proximity to trigger ubiquitination and degradation of the target protein. Yet, in-silico-driven approaches to design these heterobifunctional molecules that have the desired functional properties to induce proximity between the target protein and E3 ligase remain to be established. In this paper, we present a novel in-silico method for PROTAC design and to demonstrate the validity of our approach, we show that for a BRD4-VHL-PROTAC-mediated ternary complex known in the literature, we are able to reproduce the PROTAC binding mode, the structure of the ternary complex formed therein, and the free energy (ΔG) thermodynamics favoring ternary complexation through theoretical/computational methodologies. Further, we demonstrate the use of thermal titration molecule dynamics (TTMD) to differentiate the stability of PROTAC-mediated ternary complexes. We employ the proposed methodology to design a PROTAC for a new system of FGFR1-MDM2 to degrade the FGFR1 (fibroblast growth factor receptor 1) that is overexpressed in cancer. Our work presented here and named as PROTAC-Designer-Evaluator (PRODE) contributes to the growing literature of in-silico approaches to PROTAC design and evaluation by incorporating the latest in-silico methods and demonstrates advancement over previously published PROTAC in-silico literature.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38173211

RESUMO

BACKGROUND: The world is currently facing a growing concern regarding freshwater scarcity, which has arisen as a result of a complex interplay of various factors. Renewable energy-powered water desalination is a feasible solution to address freshwater scarcity. METHODS: This study presents a comprehensive investigation of the performance of a conventional solar still (CSS) and its modified versions, such as a still with copper plates, a still with PCM and a still with PCM and 3 wt% CuO nanoparticles blend. The experiments were carried out concurrently under identical circumstances for the CSS and the proposed stills. Prior to usage, the CuO nanoparticles and their blend with PCM were characterized through various analyses. RESULTS: The investigation showcased the copper plate attached solar still with 3 wt% CuO nanoparticles blended with PCM significantly improved the distillate production, achieving approximately 6.85 kg/m2/day. This represents an increment of approximately 23.42% compared to the still with copper plate and PCM and 69.14% related to the CSS. CONCLUSION: Moreover, the solar still with 3 wt% CuO nanoparticles blended with PCM demonstrated a thermal efficiency of 74.23% and an exergy efficiency of 9.75%. The production cost of distillate for all four stills remained at $0.03 per kg. These findings highlight the effectiveness of the proposed copper plate attached solar still with 3 wt% CuO nanoparticles blended with PCM as a viable method for producing potable water.

4.
BMC Microbiol ; 23(1): 179, 2023 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-37420194

RESUMO

Over 380 host plant species have been known to develop leaf spots as a result of the fungus Alternaria alternata. It is an aspiring pathogen that affects a variety of hosts and causes rots, blights, and leaf spots on different plant sections. In this investigation, the lipopeptides from the B. subtilis strains T3, T4, T5, and T6 were evaluated for their antifungal activities. In the genomic DNA, iturin, surfactin, and fengycin genes were found recovered from B. subtilis bacterium by PCR amplification. From different B. subtilis strains, antifungal Lipopeptides were extracted, identified by HPLC, and quantified with values for T3 (24 g/ml), T4 (32 g/ml), T5 (28 g/ml), and T6 (18 g/ml). To test the antifungal activity, the isolated lipopeptides from the B. subtilis T3, T4, T5, and T6 strains were applied to Alternaria alternata at a concentration of 10 g/ml. Lipopeptides were found to suppress Alternaria alternata at rates of T3 (75.14%), T4 (75.93%), T5 (80.40%), and T6 (85.88%). The T6 strain outperformed the other three by having the highest antifungal activity against Alternaria alternata (85.88%).


Assuntos
Antifúngicos , Bacillus subtilis , Bacillus subtilis/genética , Bacillus subtilis/química , Antifúngicos/química , Alternaria/genética , Plantas , Lipopeptídeos/química
5.
Sci Rep ; 13(1): 4064, 2023 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-36906627

RESUMO

This study aimed to screen the bioactive compounds from Prosopis juliflora leaf supercritical fluid extract and to assess its antimicrobial properties. Supercritical carbon dioxide and Soxhlet methods were used for extraction. The extract was subjected to Gas Chromatography-Mass Spectrometer (GC-MS) and Fourier Transform Infrared for the characterization of the phyto-components. When compared to soxhlet extraction, more components (35) were eluted by supercritical fluid extraction (SFE), according to GC-MS screening. Rhizoctonia bataticola, Alternaria alternata, and Colletotrichum gloeosporioides were all successfully inhibited by P. juliflora leaf SFE extract, which demonstrated strong antifungal properties with mycelium percent inhibition of 94.07%, 93.15%, and 92.43%, respectively, compared to extract from Soxhlet, which registered 55.31%, 75.63% and 45.13% mycelium inhibition respectively. Also, SFE P. juliflora extracts registered higher zone of inhibition 13.90 mm, 14.47 mm and 14.53 mm against all three test food-borne bacterial pathogens viz Escherichia coli, Salmonella enterica and Staphylococcus aureus respectively. Results obtained from GC-MS screening revealed that SFE is more efficient than soxhlet extraction in recovering the phyto-components. P. juliflora may provide antimicrobial agents, a novel natural inhibitory metabolite.


Assuntos
Anti-Infecciosos , Cromatografia com Fluido Supercrítico , Prosopis , Cromatografia Gasosa-Espectrometria de Massas , Extratos Vegetais/farmacologia , Dióxido de Carbono , Anti-Infecciosos/farmacologia , Cromatografia com Fluido Supercrítico/métodos , Folhas de Planta
6.
J Oral Maxillofac Pathol ; 26(2): 218-227, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35968187

RESUMO

Background: Lactate dehydrogenase (LDH), an intra-cellular enzyme present in all cells of the body, catalyses the final step of anaerobic glycolysis. This intra-cellular enzyme is released into the extra-cellular space after tissue disintegration, which is evident in oral squamous cell carcinoma (OSCC). However, investigations comparing Lactate dehydrogenase (LDH) levels in OSCC and healthy controls have shown conflicting findings in both serum and saliva samples. Further, Uric acid's anti-oxidant activity has been demonstrated in several diseases. Several cancers have been linked to increased uric acid levels. However, uric acid levels in oral squamous cell cancer have varied. There exists limitted research comparing serum and salivary uric acid with OSCC. Thus, the present investigation was conducted to evaluate the combined diagnostic abilities of serum and salivary LDH and uric acid in OSCC. Aim and Objective: To compare and correlate LDH and uric acid levels in serum and salivary samples of OSCC patients and healthy individuals. Material and Methods: LDH levels and uric acid levels were measured using an enzymatic method in serum and salivary samples of OSCC cases (n = 18) and healthy individuals (n = 18). Results: This study indicated statistically significant elevated levels of LDH in serum and saliva samples of OSCC patients when compared to healthy individuals. Furthermore, serum and salivary uric acid were higher in OSCC patients than in controls. This increased levels of uric acid was significant only in serum but not in saliva samples. However, salivary uric acid was found to be co-relating with serum uric acid. In addition to this, the receiver operating characteristic (ROC) curve when plotted to assess combined diagnostic abilities of all the investigations to predict oscc, indicating the diagnostic ability to be 77%. Conclusion: This study found an increase in uric acid levels in OSCC patients, which contradicts previous existing litratures. Salivary uric acid and LDH levels may be effective indicators for OSCC screening. However, because of the limited sample size, these findings should be viewed with caution.

7.
J Food Sci Technol ; 59(8): 3266-3273, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35872715

RESUMO

The study was carried out to know the quality of small grey donkey milk powder by spray dryer. Donkey milk powder moisture, fat, protein, carbohydrate and ash were 4.12 (d.b), 5.97, 22.84, 4.64 and 62.43 (%). Donkey milk powder was produced at milk total solids of 20, 25 and 30% concentration at 160, 170 and 180 °C inlet air temperature using two fluid flow nozzle type atomizer of 0.84 mm diameter, pressure of 1.75 kg.cm-2, flow rate of 0.5 L.h-1, blower speed of 2100 rpm. L * , a * , b * and aw values decreased with increasing concentrated milk feed as well as inlet air temperature. Density decreased as increase of inlet air temperature and increased as increase milk concentration. Flowability was fair according to Hausner ratio (1.25) and Carr's index (20%) values. The heat utilization efficiency increased as increase of concentration and decreased as increase of inlet air temperature. Solubility decreased as increase of concentration and inlet air temperature. Dispersibility decreased as increase of inlet air temperature and increased as increase of concentration. Wetting time increased as increase of concentration and inlet air temperature. Structure of the donkey milk powder was spherical and minerals were abundant.

8.
J Assoc Physicians India ; 70(4): 11-12, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35443491

RESUMO

The patient's history is inaccurate and unreliable in diagnosis of ALD. None of laboratory test gives an unequivocal indication of Alcohol Abuse. GGT indicates Alcohol Abuse only in background of normal LFT. After the onset of liver disease due to any etiology, GGT rise parallel to ALP. Although, AST/ALT>2 is useful marker for ALD, its valid only in Steatohepatitis. The ratio may be normal in Cirrhosis. Although serum carbohydrate deficit transferrin is most specific biomarker for ALD, its an acute phase reactant, its valid only in Steatohepatitis, not in Cirrhosis. The main metabolite of ethanol is acetaldehyde which accumulates in alcoholics. Acetaldehyde binds exposed proteins which trigger immunoglobulin production.The antibodies directed against acetaldehyde adducts are predominantly IgA type. MATERIAL: All subjects admitted to hospital with ALD with cirrhotic dose consumption were studied. The stage of ALD was decided based on serum albumin, Ultrasound abdomen and Fibroscan. Those seronegative for Viral Hepatitis were included in the study. Serum IgA, Serum IgA/IgG ratio, serum AST/ALT ratio, serum GGT and MCV were computed and correlated using Pearson's Chi-square test and ANOVA test. OBSERVATION: A total of 55 patients were studied. Mean age was 44 years with male preponderance of 91%. 24% were in steatosis,32% were in steatohepatitis, while 44% were in cirrhosis. Normal serum IgA upto 300 mg/dl. In this study, mean IgA in steatosis - 701 mg/dl, in steatohepatitis 1180mg/dl and cirrhosis- 1181 mg/dl. Normal serum IgA/ IgG ratio upto 0.2. In this study, this ratio in steatosis -0.3, steatohepatitis -0.5, cirrhosis- 0.6. There was significant correlation between IgA levels with advancing stages of ALD and amount of alcohol consumed. Since majority of subjects were cirrhotics where AST and ALT were normal, there was no association between AST/ALT ratio and IgA/IgG ratio. There was significant correlation between serum GGT and IgA/IgG ratio since majority were active alcoholics. Serum IgA>1200 mg/dl and IgA/IgG >0.5 correlated with onset of Hepatorenal Syndrome. CONCLUSION: The present study shows that IgA concentration increases in all stages of ALD, while AST/ ALT ratio increase only in Steatosis/Hepatitis. Although Hypergammaglobulinemia is known to occur in CLD, the fraction of immunoglobulin elevated indicates etiology of Liver Disease. IgA is elevated fraction in ALD. Its level can be used to decide the stage of ALD and prognosis.


Assuntos
Alcoolismo , Fígado Gorduroso , Hepatopatias Alcoólicas , Acetaldeído , Adulto , Biomarcadores , Fígado Gorduroso/diagnóstico , Fígado Gorduroso/patologia , Humanos , Imunoglobulina A , Imunoglobulina G , Fígado , Cirrose Hepática , Hepatopatias Alcoólicas/diagnóstico , Hepatopatias Alcoólicas/patologia , Masculino
9.
J Oral Maxillofac Pathol ; 26(4): 592, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37082039

RESUMO

Background: Glutathione S-transferase M1 (GSTM1) and Glutathione S-transferase T1 (GSTT1) null genotypes have been considered risk factors for many cancers. Numerous studies have been conducted to evaluate the association of null genotype of GSTM1 and GSTT1 with increased susceptibility to oral cancers, and these have produced inconsistent and inconclusive results. In the present study, the possible association of oral cancer(OC) with GSTM1 and GSTT1 null genotypes was explored by a meta analysis. Materials and Methods: A meta-analysis was conducted on published original studies retrieved from the literature using a bibliographic search from two electronic databases: MEDLINE (National library of medicine, USA) and EMBASE. The pooled odds ratio and presence of publication bias in those studies were evaluated. Results: A total of 49 studies concerning oral cancer (OC) were identified for GSTM1 null genotype. Similarly, 36 studies were identified for GSTT1 null genotype. The pooled OR was 1.551(95% confidence interval [CI]: 1.355-1.774) for the GSTM1 null genotype, while for GSTT1 null genotype, the pooled OR was 1.377 (95% CI: 1.155-1.642). No evidence of publication bias was detected among the included studies. Conclusion: The results suggest that the Glutathione S-transferase M1 and Glutathione S-transferase T1 null genotypes significantly enhances the risk of developing oral cancer by a substantial percentage.

10.
Hepatol Commun ; 5(7): 1183-1200, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34278168

RESUMO

Nonalcoholic fatty liver disease (NAFLD) has emerged as a leading cause of chronic liver disease worldwide, primarily because of the massive global increase in obesity. Despite intense research efforts in this field, the factors that govern the initiation and subsequent progression of NAFLD are poorly understood, which hampers the development of diagnostic tools and effective therapies in this area of high unmet medical need. Here we describe a regulator in molecular pathogenesis of NAFLD: STE20-type protein kinase MST4. We found that MST4 expression in human liver biopsies was positively correlated with the key features of NAFLD (i.e., hepatic steatosis, lobular inflammation, and hepatocellular ballooning). Furthermore, the silencing of MST4 attenuated lipid accumulation in human hepatocytes by stimulating ß-oxidation and triacylglycerol secretion, while inhibiting fatty acid influx and lipid synthesis. Conversely, overexpression of MST4 in human hepatocytes exacerbated fat deposition by suppressing mitochondrial fatty acid oxidation and triacylglycerol efflux, while enhancing lipogenesis. In parallel to these reciprocal alterations in lipid storage, we detected substantially decreased or aggravated oxidative/endoplasmic reticulum stress in human hepatocytes with reduced or increased MST4 levels, respectively. Interestingly, MST4 protein was predominantly associated with intracellular lipid droplets in both human and rodent hepatocytes. Conclusion: Together, our results suggest that hepatic lipid droplet-decorating protein MST4 is a critical regulatory node governing susceptibility to NAFLD and warrant future investigations to address the therapeutic potential of MST4 antagonism as a strategy to prevent or mitigate the development and aggravation of this disease.

11.
JCI Insight ; 5(24)2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33170807

RESUMO

Diabetic kidney disease (DKD) is the most common cause of severe renal disease worldwide and the single strongest predictor of mortality in diabetes patients. Kidney steatosis has emerged as a critical trigger in the pathogenesis of DKD; however, the molecular mechanism of renal lipotoxicity remains largely unknown. Our recent studies in genetic mouse models, human cell lines, and well-characterized patient cohorts have identified serine/threonine protein kinase 25 (STK25) as a critical regulator of ectopic lipid storage in several metabolic organs prone to diabetic damage. Here, we demonstrate that overexpression of STK25 aggravates renal lipid accumulation and exacerbates structural and functional kidney injury in a mouse model of DKD. Reciprocally, inhibiting STK25 signaling in mice ameliorates diet-induced renal steatosis and alleviates the development of DKD-associated pathologies. Furthermore, we find that STK25 silencing in human kidney cells protects against lipid deposition, as well as oxidative and endoplasmic reticulum stress. Together, our results suggest that STK25 regulates a critical node governing susceptibility to renal lipotoxicity and that STK25 antagonism could mitigate DKD progression.


Assuntos
Nefropatias Diabéticas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Diabetes Mellitus/metabolismo , Nefropatias Diabéticas/fisiopatologia , Nefropatias Diabéticas/prevenção & controle , Modelos Animais de Doenças , Fígado Gorduroso/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Rim/metabolismo , Rim/patologia , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Substâncias Protetoras/metabolismo , Proteínas Serina-Treonina Quinases/genética
12.
Soft Matter ; 16(46): 10439-10453, 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33057533

RESUMO

Electrohydrodynamic instabilities (EHDI) in liquid crystals form uniform and continuously variable diffractive structures when subject to certain material and geometry determined conditions. A one-dimensional grating is one such diffractive structure, where the refractive index changes periodically in a direction parallel to the initial liquid crystal director. The period of this structure has been shown previously to vary continuously between the values of the cell gap and half-cell gap approximately, allowing continuous angular modulation of optical beams but with a limited angular range. In this work, the lower pitch limit is shown to also be governed in part by the ratio of the splay and bend elastic constants (k11/k33) of the liquid crystal. A host nematic liquid crystal with standard elastic constant ratios (k11/k33 < 1) is doped with odd-alkyl-spaced dimeric liquid crystal CB7CB, to create a liquid crystal mixture with a far higher elastic constant ratio (k11/k33 > 5) than for those previously used in literature EHDI studies. The EHDI gratings formed in this new mixture exhibit pitch lengths significantly below half-cell gap, allowing up to 50% wider angle continuous steering of light. This improves the potential for application in beamsteering and diffractive optical devices.

13.
Am J Med Genet A ; 182(11): 2778-2780, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32902111

RESUMO

Genetic diagnosis depends on having available tissue to test. This can be important for many reasons, such as related to familial diagnosis in the case of another pregnancy. When blood or DNA samples from affected family members are not available, accurate prenatal diagnosis may be much more difficult and hence additional effort may be needed to obtain a genetic diagnosis in such families. We report two families with suspected monogenic disorders where attempts were made to establish the genetic etiology in deceased offspring using dried umbilical cord remnants which had been preserved by the family.


Assuntos
Deficiências do Desenvolvimento/patologia , Hepatopatias/patologia , Glicoproteínas de Membrana/genética , Hipotonia Muscular/patologia , Mutação , Infecções Respiratórias/patologia , Cordão Umbilical/química , alfa-Glucosidases/genética , Deficiências do Desenvolvimento/genética , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Lactente , Hepatopatias/genética , Masculino , Hipotonia Muscular/genética , Gravidez , Diagnóstico Pré-Natal/métodos , Infecções Respiratórias/genética
14.
FASEB J ; 33(9): 9974-9989, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31173506

RESUMO

Ectopic lipid storage in the liver is considered the main risk factor for nonalcoholic steatohepatitis (NASH). Understanding the molecular networks controlling hepatocellular lipid deposition is therefore essential for developing new strategies to effectively prevent and treat this complex disease. Here, we describe a new regulator of lipid partitioning in human hepatocytes: mammalian sterile 20-like (MST) 3. We found that MST3 protein coats lipid droplets in mouse and human liver cells. Knockdown of MST3 attenuated lipid accumulation in human hepatocytes by stimulating ß-oxidation and triacylglycerol secretion while inhibiting fatty acid influx and lipid synthesis. We also observed that lipogenic gene expression and acetyl-coenzyme A carboxylase protein abundance were reduced in MST3-deficient hepatocytes, providing insight into the molecular mechanisms underlying the decreased lipid storage. Furthermore, MST3 expression was positively correlated with key features of NASH (i.e., hepatic lipid content, lobular inflammation, and hepatocellular ballooning) in human liver biopsies. In summary, our results reveal a role of MST3 in controlling the dynamic metabolic balance of liver lipid catabolism vs. lipid anabolism. Our findings highlight MST3 as a potential drug target for the prevention and treatment of NASH and related complex metabolic diseases.-Cansby, E., Kulkarni, N. M., Magnusson, E., Kurhe, Y., Amrutkar, M., Nerstedt, A., Ståhlman, M., Sihlbom, C., Marschall, H.-U., Borén, J., Blüher, M., Mahlapuu, M. Protein kinase MST3 modulates lipid homeostasis in hepatocytes and correlates with nonalcoholic steatohepatitis in humans.


Assuntos
Hepatócitos/metabolismo , Proteínas Associadas a Gotículas Lipídicas/fisiologia , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteínas Serina-Treonina Quinases/fisiologia , Animais , Compartimento Celular , Células Cultivadas , Dieta Hiperlipídica/efeitos adversos , Gorduras na Dieta/farmacocinética , Feminino , Técnicas de Silenciamento de Genes , Homeostase , Humanos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias Hepáticas/metabolismo , Especificidade de Órgãos , Oxirredução , Estresse Oxidativo , Proteínas Serina-Treonina Quinases/análise , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Ratos , Triglicerídeos/metabolismo
15.
Cell Mol Gastroenterol Hepatol ; 7(3): 597-618, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30576769

RESUMO

BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are emerging as leading causes of liver disease worldwide. Currently, no specific pharmacologic therapy is available for NAFLD/NASH, which has been recognized as one of the major unmet medical needs of the 21st century. Our recent studies in genetic mouse models, human cell lines, and well-characterized patient cohorts have identified serine/threonine protein kinase (STK)25 as a critical regulator of hepatic lipid partitioning and NAFLD/NASH. Here, we studied the metabolic benefit of liver-specific STK25 inhibitors on NAFLD development and progression in a mouse model of diet-induced obesity. METHODS: We developed a hepatocyte-specific triantennary N-acetylgalactosamine (GalNAc)-conjugated antisense oligonucleotide (ASO) targeting Stk25 and evaluated its effect on NAFLD features in mice after chronic exposure to dietary lipids. RESULTS: We found that systemic administration of hepatocyte-targeting GalNAc-Stk25 ASO in obese mice effectively ameliorated steatosis, inflammatory infiltration, hepatic stellate cell activation, nutritional fibrosis, and hepatocellular damage in the liver compared with mice treated with GalNAc-conjugated nontargeting ASO, without any systemic toxicity or local tolerability concerns. We also observed protection against high-fat-diet-induced hepatic oxidative stress and improved mitochondrial function with Stk25 ASO treatment in mice. Moreover, GalNAc-Stk25 ASO suppressed lipogenic gene expression and acetyl-CoA carboxylase protein abundance in the liver, providing insight into the molecular mechanisms underlying repression of hepatic steatosis. CONCLUSIONS: This study provides in vivo nonclinical proof-of-principle for the metabolic benefit of liver-specific inhibition of STK25 in the context of obesity and warrants future investigations to address the therapeutic potential of GalNAc-Stk25 ASO in the prevention and treatment of NAFLD.


Assuntos
Hepatócitos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Hepatopatia Gordurosa não Alcoólica/terapia , Oligonucleotídeos Antissenso/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Acetil-CoA Carboxilase/metabolismo , Acetilglucosamina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Dieta Hiperlipídica , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Lipogênese/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Obesos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Hepatopatia Gordurosa não Alcoólica/sangue , Tamanho do Órgão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
16.
J Endocrinol ; 238(3): 187-202, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29794231

RESUMO

Whole-body energy homeostasis at over-nutrition critically depends on how well adipose tissue remodels in response to excess calories. We recently identified serine/threonine protein kinase (STK)25 as a critical regulator of ectopic lipid storage in non-adipose tissue and systemic insulin resistance in the context of nutritional stress. Here, we investigated the role of STK25 in regulation of adipose tissue dysfunction in mice challenged with a high-fat diet. We found that overexpression of STK25 in high-fat-fed mice resulted in impaired mitochondrial function and aggravated hypertrophy, inflammatory infiltration and fibrosis in adipose depots. Reciprocally, Stk25-knockout mice displayed improved mitochondrial function and were protected against diet-induced excessive fat storage, meta-inflammation and fibrosis in brown and white adipose tissues. Furthermore, in rodent HIB-1B cell line, STK25 depletion resulted in enhanced mitochondrial activity and consequently, reduced lipid droplet size, demonstrating an autonomous action for STK25 within adipocytes. In summary, we provide the first evidence for a key function of STK25 in controlling the metabolic balance of lipid utilization vs lipid storage in brown and white adipose depots, suggesting that repression of STK25 activity offers a potential strategy for establishing healthier adipose tissue in the context of chronic exposure to dietary lipids.


Assuntos
Tecido Adiposo/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Metabolismo dos Lipídeos/genética , Estresse Oxidativo/genética , Proteínas Serina-Treonina Quinases/fisiologia , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Células Cultivadas , Dieta Hiperlipídica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Gotículas Lipídicas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Serina-Treonina Quinases/genética
17.
J Biol Chem ; 293(27): 10425-10434, 2018 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-29666186

RESUMO

Dendritic cells (DC) and cytokines produced by DC play crucial roles in inducing and regulating pro-/anti-inflammatory and Th1/Th2 responses. DC are known to produce a Th1-promoting cytokine, interleukin (IL)-12, in response to malaria and other pathogenic infections, but it is thought that DC do not produce Th2-promoting cytokine, IL-4. Here, we show that a protein factor of malaria parasites induces IL-4 responses by CD11chiMHCIIhiCD3ϵ-CD49b-CD19-FcϵRI- DC via PI3K-Akt-NF-κB signaling independent of TLR-MyD88/TRIF. Malaria parasite-activated DC induced IL-4 responses by T cells both in vitro and in vivo, favoring Th2, and il-4-deficient DC were unable to induce IL-4 expression by T cells. Interestingly, lethal parasites, Plasmodium falciparum and Plasmodium berghei ANKA, induced IL-4 response primarily by CD8α- DC, whereas nonlethal Plasmodium yoelii induced IL-4 by both CD8α+ and CD8α- DC. In both P. berghei ANKA- and P. yoelii-infected mice, IL-4-expressing CD8α- DC did not express IL-12, but a distinct CD8α- DC subset expressed IL-12. In P. berghei ANKA infection, CD8α+ DC expressed IL-12 but not IL-4, whereas in P. yoelii infection, CD8α+ DC expressed IL-4 but not IL-12. These differential IL-4 and IL-12 responses by DC subsets may contribute to different Th1/Th2 development and clinical outcomes in lethal and nonlethal malaria. Our results for the first time demonstrate that a malaria protein factor induces IL-4 production by DC via PI3K-Akt-NF-κB signaling, revealing signaling and molecular mechanisms that initiate and promote Th2 development.


Assuntos
Células Dendríticas/imunologia , Interleucina-4/metabolismo , Malária/imunologia , Plasmodium yoelii/imunologia , Proteínas de Protozoários/metabolismo , Células Th2/imunologia , Proteínas Adaptadoras de Transporte Vesicular/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Citocinas/metabolismo , Células Dendríticas/metabolismo , Células Dendríticas/parasitologia , Interleucina-4/fisiologia , Malária/metabolismo , Malária/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas de Protozoários/genética , Transdução de Sinais , Células Th1/imunologia , Células Th1/metabolismo , Células Th1/parasitologia , Células Th2/metabolismo , Células Th2/parasitologia , Receptor 2 Toll-Like/fisiologia , Receptor 4 Toll-Like/fisiologia , Receptor Toll-Like 9/fisiologia
18.
Anticancer Drugs ; 28(9): 1002-1017, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28727579

RESUMO

Vorinostat [suberoylanilide hydroxamic acid (SAHA)], a histone deacetylase inhibitor, shows limited clinical activity against solid tumors when used alone. The methyl xanthine drug, pentoxifylline (PENT), has been described to have antitumor properties. The aim of this study was to look for the enhanced anticancer activities of both agents when used in combination at doses lower than their respective efficacy dose when used alone. We investigated the antitumor potential of this novel combination in vitro and in vivo. The combination index was assessed for these two drugs to look for synergistic antiproliferative activity against a broad spectrum of human cancer cell lines. Consistent additive to synergistic interactions were observed in HCT116 cells when PENT was combined with SAHA at all drug tested concentrations. The combination of SAHA and PENT induces chromatin condensation and apoptosis downstream of the pan histone deacetylase inhibition and phosphodiesterase regulation, leading to subsequent cell cycle arrest at their lower tested concentrations. Further, the ability of this combination to inhibit angiogenesis, both in vitro and in vivo, was examined and a significant inhibition in tube formation in HUVEC cells and neovascularization of Matrigel plug was observed. A significant inhibition in tumor growth was observed in severe combined immunodeficient mice bearing HCT116 (colon) and PC3 (prostate) human xenografts treated with SAHA (30 mg/kg, intraperitoneal) in combination with PENT (60 mg/kg, intraperitoneal), with no loss in body weight and 100% survival. In conclusion, these findings indicate the enhanced anticancer activity of SAHA in combination with PENT both in vitro and in vivo.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Neoplasias/tratamento farmacológico , Pentoxifilina/farmacologia , Inibidores de Fosfodiesterase/farmacologia , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sinergismo Farmacológico , Células HCT116 , Inibidores de Histona Desacetilases/administração & dosagem , Inibidores de Histona Desacetilases/farmacocinética , Células Endoteliais da Veia Umbilical Humana , Humanos , Ácidos Hidroxâmicos/administração & dosagem , Ácidos Hidroxâmicos/farmacocinética , Células MCF-7 , Masculino , Camundongos , Camundongos SCID , Neoplasias/irrigação sanguínea , Neoplasias/metabolismo , Neoplasias/patologia , Neovascularização Patológica/tratamento farmacológico , Pentoxifilina/administração & dosagem , Pentoxifilina/farmacocinética , Inibidores de Fosfodiesterase/administração & dosagem , Inibidores de Fosfodiesterase/farmacocinética , Distribuição Aleatória , Vorinostat , Ensaios Antitumorais Modelo de Xenoenxerto
19.
J Biol Chem ; 292(22): 9394-9408, 2017 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-28416609

RESUMO

In malaria, CD36 plays several roles, including mediating parasite sequestration to host organs, phagocytic clearance of parasites, and regulation of immunity. Although the functions of CD36 in parasite sequestration and phagocytosis have been clearly defined, less is known about its role in malaria immunity. Here, to understand the function of CD36 in malaria immunity, we studied parasite growth, innate and adaptive immune responses, and host survival in WT and Cd36-/- mice infected with a non-lethal strain of Plasmodium yoelii Compared with Cd36-/- mice, WT mice had lower parasitemias and were resistant to death. At early but not at later stages of infection, WT mice had higher circulatory proinflammatory cytokines and lower anti-inflammatory cytokines than Cd36-/- mice. WT mice showed higher frequencies of proinflammatory cytokine-producing and lower frequencies of anti-inflammatory cytokine-producing dendritic cells (DCs) and natural killer cells than Cd36-/- mice. Cytokines produced by co-cultures of DCs from infected mice and ovalbumin-specific, MHC class II-restricted α/ß (OT-II) T cells reflected CD36-dependent DC function. WT mice also showed increased Th1 and reduced Th2 responses compared with Cd36-/- mice, mainly at early stages of infection. Furthermore, in infected WT mice, macrophages and neutrophils expressed higher levels of phagocytic receptors and showed enhanced phagocytosis of parasite-infected erythrocytes than those in Cd36-/- mice in an IFN-γ-dependent manner. However, there were no differences in malaria-induced humoral responses between WT and Cd36-/- mice. Overall, the results show that CD36 plays a significant role in controlling parasite burden by contributing to proinflammatory cytokine responses by DCs and natural killer cells, Th1 development, phagocytic receptor expression, and phagocytic activity.


Assuntos
Antígenos CD36/imunologia , Imunidade Humoral , Malária/imunologia , Parasitemia/imunologia , Plasmodium yoelii/imunologia , Animais , Antígenos CD36/genética , Células Dendríticas/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Interferon gama/genética , Interferon gama/imunologia , Células Matadoras Naturais/imunologia , Macrófagos/imunologia , Malária/genética , Camundongos , Camundongos Knockout , Neutrófilos/imunologia , Parasitemia/genética , Fagocitose/genética , Células Th1/imunologia , Células Th2/imunologia
20.
J Biol Chem ; 291(48): 24922-24930, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27742835

RESUMO

Lung M2 macrophages are regulators of airway inflammation, associated with poor lung function in allergic asthma. Previously, we demonstrated that IL-4-induced M2 gene expression correlated with tyrosine phosphorylation of the insulin receptor substrate-2 (IRS-2) in macrophages. We hypothesized that negative regulation of IRS-2 activity after IL-4 stimulation is dependent upon serine phosphorylation of IRS-2. Herein, we describe an inverse relationship between tyrosine phosphorylation (Tyr(P)) and serine phosphorylation (Ser(P)) of IRS-2 after IL-4 stimulation. Inhibiting serine phosphatase activity increased Ser(P)-IRS-2 and decreased Tyr(P)-IRS-2 leading to reduced M2 gene expression (CD200R, CCL22, MMP12, and TGM2). We found that inhibition of p70S6K, downstream of TORC1, resulted in diminished Ser(P)-IRS-2 and prolonged Tyr(P)-IRS-2 as well. Inhibition of p70S6K increased expression of CD200R and CCL22 indicating that p70S6K negatively regulates some, but not all, human M2 genes. Knocking down GRB10, another negative regulatory protein downstream of TORC1, enhanced both Tyr(P)-IRS-2 and increased expression of all four M2 genes. Furthermore, GRB10 associated with IRS-2, NEDD4.2 (an E3-ubiquitin ligase), IL-4Rα, and γC after IL-4 stimulation. Both IL-4Rα and γC were ubiquitinated after 30 min of IL-4 treatment, suggesting that GRB10 may regulate degradation of the IL-4 receptor-signaling complex through interactions with NEDD4.2. Taken together, these data highlight two novel regulatory proteins that could be therapeutically manipulated to limit IL-4-induced IRS-2 signaling and polarization of M2 macrophages in allergic inflammation.


Assuntos
Proteína Adaptadora GRB10/metabolismo , Proteínas Substratos do Receptor de Insulina/metabolismo , Interleucina-4/metabolismo , Macrófagos/metabolismo , Complexos Multiproteicos/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Proteína Adaptadora GRB10/genética , Regulação da Expressão Gênica/genética , Humanos , Hipersensibilidade/genética , Hipersensibilidade/metabolismo , Proteínas Substratos do Receptor de Insulina/genética , Interleucina-4/genética , Alvo Mecanístico do Complexo 1 de Rapamicina , Complexos Multiproteicos/genética , Ubiquitina-Proteína Ligases Nedd4 , Receptores de Interleucina-4/genética , Receptores de Interleucina-4/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/genética , Serina-Treonina Quinases TOR/genética , Células U937 , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
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