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1.
Antimicrob Agents Chemother ; 68(1): e0095523, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38092678

RESUMO

The newly emerged pathogen, Candida auris, presents a serious threat to public health worldwide. This multidrug-resistant yeast often colonizes and persists on the skin of patients, can easily spread from person to person, and can cause life-threatening systemic infections. New antifungal therapies are therefore urgently needed to limit and control both superficial and systemic C. auris infections. In this study, we designed a novel antifungal agent, PQA-Az-13, that contains a combination of indazole, pyrrolidine, and arylpiperazine scaffolds substituted with a trifluoromethyl moiety. PQA-Az-13 demonstrated antifungal activity against biofilms of a set of 10 different C. auris clinical isolates, representing all four geographical clades distinguished within this species. This compound showed strong activity, with MIC values between 0.67 and 1.25 µg/mL. Cellular proteomics indicated that PQA-Az-13 partially or completely inhibited numerous enzymatic proteins in C. auris biofilms, particularly those involved in both amino acid biosynthesis and metabolism processes, as well as in general energy-producing processes. Due to its hydrophobic nature and limited aqueous solubility, PQA-Az-13 was encapsulated in cationic liposomes composed of soybean phosphatidylcholine (SPC), 1,2-dioleoyloxy-3-trimethylammonium-propane chloride (DOTAP), and N-(carbonyl-methoxypolyethylene glycol-2000)-1,2-distearoyl-sn-glycero-3-phosphoethanolamine, sodium salt (DSPE-PEG 2000), and characterized by biophysical and spectral techniques. These PQA-Az-13-loaded liposomes displayed a mean size of 76.4 nm, a positive charge of +45.0 mV, a high encapsulation efficiency of 97.2%, excellent stability, and no toxicity to normal human dermal fibroblasts. PQA-Az-13 liposomes demonstrated enhanced antifungal activity levels against both C. auris in in vitro biofilms and ex vivo skin colonization models. These initial results suggest that molecules like PQA-Az-13 warrant further study and development.


Assuntos
Antifúngicos , Candida , Humanos , Antifúngicos/farmacologia , Candida auris , Lipossomos , Testes de Sensibilidade Microbiana , Biofilmes
2.
Int J Mol Sci ; 24(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37446046

RESUMO

Colorectal cancer is a heterogenous group of neoplasms showing a variety of clinical and pathological features depending on their anatomical location. Sphingolipids are involved in the formation and progression of cancers, and their changes are an important part of the abnormalities observed during carcinogenesis. Because the course of rectal and colonic cancer differs, the aim of the study was to assess whether the sphingolipid profile is also different in tumors of these two regions. Using a combination of ultra-high-performance liquid chromatography combined with triple quadrupole mass spectrometry, differences in the amounts of cellular sphingolipids were found in colorectal cancer. Sphingosine content was higher in rectal cancer than in adjacent healthy tissue, while the content of two ceramides (C18:0-Cer and C20:0-Cer) was lower. In colon cancer, a higher content of sphingosine, sphinganine, sphingosine-1-phosphate, and two ceramides (C14:0-Cer and C24:0-Cer) was found compared to healthy tissue, but there was no decrease in the amount of any of the assessed sphingolipids. In rectal cancer, the content of sphinganine and three ceramides (C16:0-Cer, C22:0-Cer, C24:0-Cer), as well as the entire pool of ceramides, was significantly lower compared to colon cancer. The S1P/Cer ratio in rectal cancer (S1P/C18:1-Cer, S1P/C20:0-Cer, S1P/C22:0-Cer, S1P/C24:1-Cer) and in colon cancer (S1P/C18:0-Cer, S1P/C18:1-Cer, S1P/C20:0-Cer) was higher than in adjacent healthy tissue and did not differ between the two sites (rectal cancer vs. colonic cancer). It seems that the development of colorectal cancer is accompanied by complex changes in the metabolism of sphingolipids, causing not only qualitative shifts in the ceramide pool of cancer tissue but also quantitative disturbances, depending on the location of the primary tumor.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Humanos , Esfingolipídeos/metabolismo , Esfingosina/metabolismo , Ceramidas/metabolismo , Lisofosfolipídeos/metabolismo
3.
Cancers (Basel) ; 15(12)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37370870

RESUMO

Reliable indicators of cancer advancement have actively been sought recently. The detection of colorectal cancer progression markers is essential in improving diagnostic and therapeutic protocols. The aim of the study was to investigate the profile of E-cadherin expression in colorectal cancer tissue depending on the TNM staging and its correlation with several clinical and histopathological features. The study included 55 colorectal cancer patients admitted to the surgical ward for elective surgery. Tissue samples were obtained from resected specimens. Different distributions of E-cadherin expression within tumors were observed; the highest percentage of positive E-cadherin expression was found in the invasive front and in the tumor center. Additionally, the different cellular distribution of E-cadherin expression was noticed; weak membranous E-cadherin expression was the highest in the invasive front and in the budding sites, but a strong membranous pattern was most frequent in the tumor center. Various distributions of E-cadherin expression depending on cancer progression were also found; E-cadherin expression in node-positive patients was lower in the tumor center and in the tumor invasive front, whereas, in patients with distant metastases, the expression of E-Cadherin was lower in the budding sites. In patients with higher TNM stages, E-cadherin expression was lower within the tumor (in the budding sites, tumor center, and invasive front). In tumors with lymphoid follicles, E-cadherin expression was higher in all localizations within the primary tumor. E-cadherin expression in the tumor center was also lower in tumors with some higher tumor budding parameters (areas of poorly differentiated components and poorly differentiated clusters). E-cadherin expression was found to be lower at the tumor center in younger individuals, at the budding sites in men, and at the surrounding lymph nodes in rectal tumors. Low E-cadherin expression appears to be a reliable indicator of higher cancer staging and progression. When assessing the advancement of cancer, apart from the TNM classification, it is beneficial to also consider the expression of E-cadherin. High tumor budding, the poverty of lymphoid follicles, and low E-cadherin expression analyzed simultaneously may contribute to a reliable assessment of colorectal cancer staging. These three histopathological features complement each other, and their investigation, together with conventional tumor staging and grading, may be very helpful in predicting the prognosis of colorectal cancer patients and qualifying them for the best treatment. The role of E-cadherin in the diagnosis and treatment of colorectal cancer, as a part of a personalized medicine strategy, still requires comprehensive, prospective clinical evaluations to precisely target the optimal therapies for the right patients at the right time.

4.
Int J Mol Sci ; 24(8)2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37108361

RESUMO

Sphingosine-1-phosphate (S1P) and ceramides (Cer) are engaged in key events of signal transduction, but their involvement in the pathogenesis of colorectal cancer is not conclusive. The aim of our study was to investigate how the modulation of sphingolipid metabolism through the silencing of the genes involved in the formation (SPHK1) and degradation (SGPL1) of sphingosine-1-phosphate would affect the sphingolipid profile and apoptosis of HCT-116 human colorectal cancer cells. Silencing of SPHK1 expression decreased S1P content in HCT-116 cells, which was accompanied by an elevation in sphingosine, C18:0-Cer, and C18:1-Cer, increase in the expression and activation of Caspase-3 and -9, and augmentation of apoptosis. Interestingly, silencing of SGLP1 expression increased cellular content of both the S1P and Cer (C16:0-; C18:0-; C18:1-; C20:0-; and C22:0-Cer), yet inhibited activation of Caspase-3 and upregulated protein expression of Cathepsin-D. The above findings suggest that modulation of the S1P level and S1P/Cer ratio regulates both cellular apoptosis and CRC metastasis through Cathepsin-D modulation. The cellular ratio of S1P/Cer seems to be a crucial component of the above mechanism.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Humanos , Esfingosina/metabolismo , Caspase 3/genética , Apoptose , Ceramidas/metabolismo , Lisofosfolipídeos/metabolismo , Esfingolipídeos/farmacologia , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Neoplasias do Colo/genética , Neoplasias Colorretais/genética , Catepsinas/farmacologia
5.
Pharmaceutics ; 15(1)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36678808

RESUMO

Pancreatic cancer (PC) is one of the deadliest cancers so there is an urgent need to develop new drugs and therapies to treat it. Liposome-based formulations of naturally-derived bioactive compounds are promising anticancer candidates due to their potential for passive accumulation in tumor tissues, protection against payload degradation, and prevention of non-specific toxicity. We chose the naturally-derived flavonoid baicalein (BAI) due to its promising effect against pancreatic ductal adenocarcinoma (PDAC) and encapsulated it into a liposomal bilayer using the passive loading method, with an almost 90% efficiency. We performed a morphological and stability analysis of the obtained BAI liposomal formulation and evaluated its activity on two-dimensional and three-dimensional pancreatic cell models. As the result, we obtained a stable BAI-encapsulated liposomal suspension with a size of 100.9 nm ± 2.7 and homogeneity PDI = 0.124 ± 0.02, suitable for intravenous administration. Furthermore, this formulation showed high cytotoxic activity towards AsPC-1 and BxPC-3 PDAC cell lines (IC50 values ranging from 21 ± 3.6 µM to 27.6 ± 4.1 µM), with limited toxicity towards normal NHDF cells and a lack of hemolytic activity. Based on these results, this new BAI liposomal formulation is an excellent candidate for potential anti-PDAC therapy.

6.
Sci Rep ; 12(1): 21732, 2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36526699

RESUMO

Colorectal cancer (CRC) affects more than 1,000,000 people worldwide each year. Recently, the number of young patients with early-onset colorectal cancer has increased, and right-sided colorectal cancer is still often diagnosed only in advanced stages. The TNM classification is not perfect for CRC staging. This study aimed to perform, for the first time, simultaneous analysis of tumor-infiltrating immune cell density, presence of lymphoid follicles, and budding status in CRC tissue. Intraoperative samples of neoplastic tissue were collected from 195 consecutive patients who were admitted to the surgical ward for elective colorectal surgery. Histological parameters were assessed in the tissue samples: tumor budding foci, poorly differentiated clusters and areas of poorly differentiated components. Tumor-infiltrating immune cells (tumor-associated neutrophils and tumor-infiltrating lymphocytes) were detected in five randomly chosen, areas at the tumor center and at the invasive front. Additionally, the presence of lymphoid follicles in CRC tissue was assessed. Tumor budding parameters were positively correlated with colorectal cancer advancement or histologic (mucinous) type of CRC. The number of poorly differentiated clusters was higher in younger patients. Lower densities of CD3 and CD4 lymphocytes were seen in CRC with a greater depth of tumor invasion. Lower densities of CD3 and CD8 lymphocytes were found in CRC with metastases to the surrounding lymph nodes. The lower density of CD8 lymphocytes was observed in CRC with distant metastases. Lower densities of tumor-associated neutrophils and tumor-infiltrating lymphocytes (CD3 and CD8) were revealed in CRC without lymphoid follicles. The number of lymphoid follicles was higher in patients with less advanced CRCs. Three histopathology markers, such as high tumor budding, scanty lymphocyte infiltration, and the poverty of lymphoid follicles, complement each other, appear to be reliable indicators of colorectal cancer progression, and could be useful in everyday medical practice, but their widespread use requires further research. We propose to take into account these markers, in the assessment of colorectal cancer advancement, in addition to the TNM classification.


Assuntos
Neoplasias Colorretais , Humanos , Neoplasias Colorretais/patologia , Linfócitos do Interstício Tumoral , Estadiamento de Neoplasias , Linfócitos T CD8-Positivos , Prognóstico
7.
Int J Mol Sci ; 23(10)2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35628352

RESUMO

Despite many attempts, trials, and treatment procedures, pancreatic ductal adenocarcinoma (PDAC) still ranks among the most deadly and treatment-resistant types of cancer. Hence, there is still an urgent need to develop new molecules, drugs, and therapeutic methods against PDAC. Naturally derived compounds, such as pentacyclic terpenoids, have gained attention because of their high cytotoxic activity toward pancreatic cancer cells. Ursolic acid (UA), as an example, possesses a wide anticancer activity spectrum and can potentially be a good candidate for anti-PDAC therapy. However, due to its minimal water solubility, it is necessary to prepare an optimal nano-sized vehicle to overcome the low bioavailability issue. Poly(lactic-co-glycolic acid) (PLGA) polymeric nanocarriers seem to be an essential tool for ursolic acid delivery and can overcome the lack of biological activity observed after being incorporated within liposomes. PLGA modification, with the addition of PEGylated phospholipids forming the lipid shell around the polymeric core, can provide additional beneficial properties to the designed nanocarrier. We prepared UA-loaded hybrid PLGA/lipid nanoparticles using a nanoprecipitation method and subsequently performed an MTT cytotoxicity assay for AsPC-1 and BxPC-3 cells and determined the hemolytic effect on human erythrocytes with transmission electron microscopic (TEM) visualization of the nanoparticles and their cellular uptake. Hybrid UA-loaded lipid nanoparticles were also examined in terms of their stability, coating dynamics, and ursolic acid loading. We established innovative and repeatable preparation procedures for novel hybrid nanoparticles and obtained biologically active nanocarriers for ursolic acid with an IC50 below 20 µM, with an appropriate size for intravenous dosage (around 150 nm), high homogeneity of the sample (below 0.2), satisfactory encapsulation efficiency (up to 70%) and excellent stability. The new type of hybrid UA-PLGA nanoparticles represents a further step in the development of potentially effective PDAC therapies based on novel, biologically active, and promising triterpenoids.


Assuntos
Adenocarcinoma , Nanopartículas , Neoplasias Pancreáticas , Triterpenos , Humanos , Ácido Láctico , Lipossomos , Neoplasias Pancreáticas/tratamento farmacológico , Tamanho da Partícula , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Triterpenos/farmacologia , Ácido Ursólico
8.
Acta Physiol (Oxf) ; 235(3): e13816, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35347845

RESUMO

AIM & METHODS: Extreme endurance exercise provides a valuable research model for understanding the adaptive metabolic response of older and younger individuals to intense physical activity. Here, we compare a wide range of metabolic and physiologic parameters in two cohorts of seven trained men, age 30 ± 5 years or age 65 ± 6 years, before and after the participants travelled ≈3000 km by bicycle over 15 days. RESULTS: Over the 15-day exercise intervention, participants lost 2-3 kg fat mass with no significant change in body weight. V̇O2 max did not change in younger cyclists, but decreased (p = 0.06) in the older cohort. The resting plasma FFA concentration decreased markedly in both groups, and plasma glucose increased in the younger group. In the older cohort, plasma LDL-cholesterol and plasma triglyceride decreased. In skeletal muscle, fat transporters CD36 and FABPm remained unchanged. The glucose handling proteins GLUT4 and SNAP23 increased in both groups. Mitochondrial ROS production decreased in both groups, and ADP sensitivity increased in skeletal muscle in the older but not in the younger cohort. CONCLUSION: In summary, these data suggest that older but not younger individuals experience a negative adaptive response affecting cardiovascular function in response to extreme endurance exercise, while a positive response to the same exercise intervention is observed in peripheral tissues in younger and older men. The results also suggest that the adaptive thresholds differ in younger and old men, and this difference primarily affects central cardiovascular functions in older men after extreme endurance exercise.


Assuntos
Exercício Físico , Músculo Esquelético , Adulto , Idoso , Peso Corporal , Exercício Físico/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Resistência Física/fisiologia , Descanso/fisiologia , Triglicerídeos/metabolismo
9.
Int J Mol Sci ; 22(22)2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34830000

RESUMO

6-aminohexanoic acid is an ω-amino acid with a hydrophobic, flexible structure. Although the ω-amino acid in question is mainly used clinically as an antifibrinolytic drug, other applications are also interesting and important. This synthetic lysine derivative, without an α-amino group, plays a significant role in chemical synthesis of modified peptides and in the polyamide synthetic fibers (nylon) industry. It is also often used as a linker in various biologically active structures. This review concentrates on the role of 6-aminohexanoic acid in the structure of various molecules.


Assuntos
Aminoácidos/química , Ácido Aminocaproico/química , Antifibrinolíticos/química , Lisina/química , Sequência de Aminoácidos/genética , Aminoácidos/genética , Antifibrinolíticos/uso terapêutico , Sítios de Ligação/genética , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lisina/análogos & derivados , Peptídeos/química , Peptídeos/genética
10.
Materials (Basel) ; 14(17)2021 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-34501007

RESUMO

Among all the types of cancer, Pancreatic Ductal Adenocarcinoma remains one of the deadliest and hardest to fight and there is a critical unmet need for new drugs and therapies for its treatment. Naturally derived compounds, such as pentacyclic triterpenoids, have gathered attention because of their high cytotoxic potential towards pancreatic cancer cells, with a wide biological activity spectrum, with ursolic acid (UA) being one of the most interesting. However, due to its minimal water solubility, it is necessary to prepare a nanocarrier vehicle to aid in the delivery of this compound. Poly(lactic-co-glycolic acid) or PLGA polymeric nanocarriers are an essential tool for ursolic acid delivery and can overcome the lack in its biological activity observed after incorporating within liposomes. We prepared UA-PLGA nanoparticles with a PEG modification, to achieve a long circulation time, by using a nanoprecipitation method and subsequently performed an MTT cytotoxicity assay towards AsPC-1 and BxPC-3 cells, with TEM visualization of the nanoparticles and their cellular uptake. We established repeatable preparation procedures of the nanoparticles and achieved biologically active nanocarriers with an IC50 below 30 µM, with an appropriate size for intravenous dosage (around 140 nm), high sample homogeneity (below 0.2) and reasonable encapsulation efficiency (up to 50%). These results represent the first steps in the development of potentially effective PDAC therapies based on novel biologically active and promising triterpenoids.

11.
Biomolecules ; 10(4)2020 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-32325909

RESUMO

Much attention is paid to different sphingolipid pathways because of their possible use in diagnostics and treatment. However, the activity status and significance of ceramide pathways in colorectal cancer are still unclear. We analyzed colorectal cancer patients to evaluate sphingolipid profiles in the blood, colorectal cancer (CRC) tissues, and healthy surrounding colorectal tissues of the same patient, simultaneously, using liquid chromatography coupled with triple quadrupole mass spectrometry. Furthermore, we measured protein expression of de novo ceramide synthesis enzymes and mitochondrial markers in tissues using western blot. We confirmed the different sphingolipid contents in colorectal cancer tissue compared to healthy surrounding tissues. Furthermore, we showed changed amounts of several ceramides in more advanced colorectal cancer tissue and found a prominently higher circulating level of several of them. Moreover, we observed a relationship between the amounts of some ceramide species in colorectal cancer tissue and plasma depending on the stage of colorectal cancer according to TNM (tumors, nodes, metastasis) classification. We think that the combined measurement of several ceramide concentrations in plasma can help distinguish early-stage lesions from advanced colorectal cancer and can help produce a screening test to detect early colorectal cancer.


Assuntos
Ceramidas/metabolismo , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/metabolismo , Metabolômica , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Estadiamento de Neoplasias , Curva ROC , Esfingolipídeos/sangue
12.
Biomolecules ; 9(10)2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31652642

RESUMO

This study is the first to assess the diagnostic utility of redox biomarkers in patients with colorectal cancer (CRC). Antioxidant barrier (Cu,Zn-superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), uric acid (UA), reduced glutathione (GSH)), redox status (total antioxidant (TAC)/oxidant status (TOS), ferric reducing ability (FRAP)), and oxidative damage products (advanced glycation end products (AGE), advanced oxidation protein products (AOPP), malondialdehyde (MDA)) were measured in serum/plasma samples of 50 CRC patients. The activity of SOD was significantly higher whereas the activity of CAT, GPx and GR was considerably lower in CRC patients compared to the control group (p < 0.0001). Levels of UA, TOS, and OSI and concentrations of AGE, AOPP, and MDA were significantly higher, and the levels of GSH, TAC, and FRAP were considerably lower in CRC patients compared to the healthy controls (p < 0.0001). AUC for CAT with respect to presence of lymph node metastasis was 0.7450 (p = 0.0036), whereas AUC for MDA according to the depth of tumour invasion was 0.7457 (p = 0.0118). CRC is associated with enzymatic/non-enzymatic redox imbalance as well as increased oxidative damage to proteins and lipids. Redox biomarkers can be potential diagnostic indicators of CRC advancement.


Assuntos
Antioxidantes/metabolismo , Biomarcadores Tumorais/metabolismo , Catalase/metabolismo , Neoplasias Colorretais/metabolismo , Malondialdeído/metabolismo , Estresse Oxidativo , Biomarcadores Tumorais/sangue , Catalase/sangue , Neoplasias Colorretais/sangue , Neoplasias Colorretais/diagnóstico , Feminino , Humanos , Masculino , Malondialdeído/sangue , Oxirredução , Curva ROC
13.
Nutrition ; 63-64: 126-133, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30959381

RESUMO

OBJECTIVES: Adipose tissue plays a central role in the pathogenesis of insulin resistance (IR) and type 2 diabetes. However, the molecular changes that promote these diseases are not completely understood. Several studies demonstrated that ceramide (Cer) and diacylglycerol (DAG) accumulation in muscle is associated with IR. The aim of this study was to explain whether a high-fat diet (HFD) leads to bioactive lipid accumulation in adipose tissue and how metformin affects the lipid content in adipocytes and the concentration of plasma adipocytokines. METHODS: The experiments were conducted on male Wistar rats divided into three groups: control, HFD-fed, and HFD-fed and treated with metformin. Cer and DAGs were analyzed by liquid chromatography tandem mass spectrometry. Phosphorylation of hormone-sensitive lipase (HSL) was analyzed by Western blot. Oral glucose tolerance and insulin tolerance tests were also performed. Plasma adiponectin and tumor necrosis factor (TNF)-α concentration were measured by enzyme-linked immunosorbent assay. RESULTS: HFD induced IR and elevated DAGs and Cer content in subcutaneous and visceral adipose tissues, which was accompanied by an increased phosphorylation of HSL. Metformin improved insulin sensitivity, decreased Cer and DAG levels, and attenuated the phosphorylation of HSL in both fat depots. Furthermore, we observed a strong correlation between adiponectin (negative) and TNF-α (positive) and bioactive lipids in both fat tissues. CONCLUSIONS: These results indicated that bioactive lipids accumulation in adipose tissue influences the induction of IR and, at least in part, answered the question of what the insulin-sensitizing effect of metformin at the level of adipose tissue is.


Assuntos
Adipocinas/sangue , Tecido Adiposo/metabolismo , Hipoglicemiantes/farmacologia , Resistência à Insulina/fisiologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Metformina/farmacologia , Animais , Ceramidas/metabolismo , Dieta Hiperlipídica/efeitos adversos , Diglicerídeos/metabolismo , Teste de Tolerância a Glucose , Insulina/sangue , Masculino , Fosforilação/efeitos dos fármacos , Ratos , Ratos Wistar , Esterol Esterase/efeitos dos fármacos
14.
J Cell Physiol ; 234(2): 1851-1861, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30067865

RESUMO

Liver, as one of the most important organs involved in lipids and glucose metabolism, is perceived as a key tissue for pharmacotherapy of insulin resistance (IRes) and type 2 diabetes. Ceramides (Cer) are biologically active lipids, which accumulation is associated with the induction of muscle IRes. We sought to determine the role of intrahepatic bioactive lipids production on insulin action in liver of insulin-resistant rats and after myriocin administration. The experiments were conducted on male Wistar rats divided into three groups: Control, fed high-fat diet (HFD), and fed HFD and treated with myriocin (HFD/Myr). Before sacrifice, the animals were infused with a [U-13 C]palmitate to calculate lipid synthesis rate by means of tracer incorporation technique in particular lipid groups. Liver Cer, diacylglycerols (DAG), acyl-carnitine concentration, and isotopic enrichment were analyzed by LC/MS/MS. Proteins involved in lipid metabolism and insulin pathway were analyzed by western blot analysis. An OGTT and ITT was also performed. HFD-induced IRes and increased both the synthesis rate and the content of DAG and Cer, which was accompanied by inhibition of an insulin pathway. Interestingly, myriocin treatment reduced synthesis rate not only of Cer but also DAG and improved insulin sensitivity. We conclude that the insulin-sensitizing action of myriocin in the liver is a result of the lack of inhibitory effect of lipids on the insulin pathway, due to the reduction of their synthesis rate. This is the first study showing how the synthesis rate of individual lipid groups in liver changes after myriocin administration.


Assuntos
Glicemia/efeitos dos fármacos , Ceramidas/metabolismo , Dieta Hiperlipídica , Inibidores Enzimáticos/farmacologia , Ácidos Graxos Monoinsaturados/farmacologia , Resistência à Insulina , Insulina/sangue , Fígado/efeitos dos fármacos , Animais , Biomarcadores/sangue , Glicemia/metabolismo , Carnitina/análogos & derivados , Carnitina/metabolismo , Carnitina O-Palmitoiltransferase/metabolismo , Humanos , Fígado/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Ratos Wistar , Serina C-Palmitoiltransferase/antagonistas & inibidores , Serina C-Palmitoiltransferase/metabolismo , Transdução de Sinais
15.
Int J Mol Sci ; 19(12)2018 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-30545025

RESUMO

Ceramide accumulation in muscle and in liver is implicated in the induction of insulin resistance. Much less in known about the role of ceramide in adipose tissue. The aim of the present study was to elucidate the role of ceramide in adipose tissue and to clarify whether lipids participate in the regulation of adipocytokine secretion. The experiments were performed on male Wistar rats divided into three groups: 1. Control, 2. fed high fat diet (HFD), and 3. fed HFD and treated with myriocin. Ceramide (Cer) and diacylglycerol (DAG) content were analyzed by LC/MS/MS. Hormone sensitive lipase (HSL) phosphorylation was analyzed by Western Blot. Plasma adiponectin and tumor necrosis factor alpha (TNF-α) concentration were measured by enzyme-linked immunosorbent assay. An oral glucose tolerance test (OGTT) and insulin tolerance test (ITT) was also performed. In HFD group, total DAG and Cer content was elevated in both subcutaneous and visceral adipose tissue, which was accompanied by increased glucose, insulin, and HOMA-IR value. Myriocin treatment restored HOMA-IR as well as glucose and insulin concentration to control values. Moreover, myriocin decreased not only Cer, but also DAG levels in both fat depots. Furthermore, we observed a strong correlation between adiponectin (negative) and TNF-α (positive) and Cer in both fat tissues, which suggests that Cer is involved in the regulation of adipocytokine secretion.


Assuntos
Adipocinas/metabolismo , Tecido Adiposo/metabolismo , Ceramidas/metabolismo , Tecido Adiposo/efeitos dos fármacos , Animais , Dieta Hiperlipídica , Diglicerídeos/metabolismo , Ácidos Graxos Monoinsaturados/farmacologia , Teste de Tolerância a Glucose , Resistência à Insulina , Masculino , Fosforilação/efeitos dos fármacos , Ratos , Ratos Wistar , Esterol Esterase/metabolismo , Espectrometria de Massas em Tandem
16.
Pol Przegl Chir ; 89(4): 41-47, 2017 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-28905804

RESUMO

We report a rare case of a large mediastinal pancreatic pseudocyst compressing the left atrium and the esophagus and causing dyspnea, palpitations, and emesis. Chest radiograph was non-diagnostic, esophagogastroduodenoscopy showed diffuse extrinsic compression of the distal esophagus and gastric corpus, but a definitive diagnosis was confirmed by computed tomography. We decided to perform surgery due to the recurrence of the pancreatic pseudocyst, a history of unsuccessful radiologically guided external drainage a few years earlier, and a very large diameter of the pseudocyst causing acute cardio-pulmonary distress syndrome.


Assuntos
Cisto Mediastínico/diagnóstico por imagem , Cisto Mediastínico/cirurgia , Pseudocisto Pancreático/diagnóstico por imagem , Pseudocisto Pancreático/cirurgia , Adulto , Feminino , Humanos , Cisto Mediastínico/etiologia , Pseudocisto Pancreático/complicações , Tomografia Computadorizada por Raios X
17.
World J Gastroenterol ; 22(40): 8883-8891, 2016 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-27833379

RESUMO

Gastric polyps become a major clinical problem because of high prevalence and tendency to malignant transformation of some of them. The development of gastric hyperplastic polyps results from excessive proliferation of foveolar cells accompanied by their increased exfoliation, and they are macroscopically indistinguishable from other polyps with lower or higher malignant potential. Panendoscopy allows detection and differentiation of gastric polyps, usually after obtaining histopathological biopsy specimens. Unremoved gastric hyperplastic polyps may enlarge and sometimes spontaneously undergo a sequential progression to cancer. For this reason, gastric hyperplastic polyps larger than 5 mm in size should be removed in one piece. After excision of polyps with atypical focal lesion, endoscopic surveillance is suggested depending on histopathological diagnosis and possibility of confirming the completeness of endoscopic resection. Because of the risk of cancer development also in gastric mucosa outside the polyp, neighboring fragments of gastric mucosa should undergo microscopic investigations. This procedure allows for identification of patients who can benefit most from oncological endoscopic surveillance. If Helicobacter pylori (H. pylori) infection of the gastric mucosa is confirmed, treatment strategies should include eradication of bacteria, which may prevent progression of intestinal metaplasia. The efficacy of H. pylori eradication should be checked 3-6 mo later.


Assuntos
Carcinoma in Situ/etiologia , Pólipos/patologia , Gastropatias/patologia , Estômago/patologia , Carcinoma in Situ/patologia , Diagnóstico Diferencial , Mucosa Gástrica/patologia , Humanos , Hiperplasia , Pólipos/complicações , Pólipos/diagnóstico , Pólipos/terapia , Gastropatias/complicações , Gastropatias/diagnóstico , Gastropatias/terapia
18.
Gastroenterol Rep (Oxf) ; 4(2): 158-61, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25361760

RESUMO

This paper reports a rare case of early adenocarcinoma within the gastric hyperplastic polyp, that was completely resected during an endoscopic procedure, and discusses current recommendations in such cases. Endoscopic resection of polyps with focal dysplasia or cancer is commonly indicated, as long as the procedure can be performed safely. After complete excision of a polyp with atypical focal lesion, endoscopic surveillance is suggested. The frequency of surveillance endoscopy should depend on the precise histopathological diagnosis and possibility of confirming the completeness of the endoscopic resection. If the completeness of the procedure is confirmed both macro- and microscopically, gastric resection does not have to be performed. A follow-up esophago-gastroduodenoscopy should be performed at 1 year and then at 3 years.

19.
J Hazard Mater ; 159(1): 152-7, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18440700

RESUMO

A risk matrix is a mechanism to characterize and rank process risks that are typically identified through one or more multifunctional reviews (e.g., process hazard analysis, audits, or incident investigation). This paper describes a procedure for developing a fuzzy risk matrix that may be used for emerging fuzzy logic applications in different safety analyses (e.g., LOPA). The fuzzification of frequency and severity of the consequences of the incident scenario are described which are basic inputs for fuzzy risk matrix. Subsequently using different design of risk matrix, fuzzy rules are established enabling the development of fuzzy risk matrices. Three types of fuzzy risk matrix have been developed (low-cost, standard, and high-cost), and using a distillation column case study, the effect of the design on final defuzzified risk index is demonstrated.


Assuntos
Lógica Fuzzy , Medição de Risco , Gestão de Riscos
20.
Kardiol Pol ; 65(7): 806-9, 2007 Jul.
Artigo em Polonês | MEDLINE | ID: mdl-17694462

RESUMO

Non-infective pericarditis in some cases may be caused by secondary amyloidosis. Amyloidosis is a metabolic disorder in which amyloid protein is deposited in various organs and destroys them. The most frequent location of systemic amyloidosis are the kidneys. In this case study we report a 74-year-old man who was admitted to hospital due to very poor condition, generalised oedema and severe dyspnoea. Since 2003 the patient had been hospitalised many times due to pericarditis of unknown aetiology. In this case we diagnosed exudative pericarditis due to nephrotic syndrome caused by secondary kidney amyloidosis which occurs very rarely.


Assuntos
Amiloidose/complicações , Nefropatias/complicações , Derrame Pericárdico/etiologia , Pericardite/diagnóstico , Pericardite/etiologia , Idoso , Eletrocardiografia , Humanos , Masculino , Síndrome Nefrótica/etiologia
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