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1.
J Cell Mol Med ; 24(5): 2981-2992, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32022429

RESUMO

Recent studies have established a concept of tumour necrosis factor-α (TNF-α)/Fas signalling crosstalk, highlighting TNF-α as a critical cytokine in sensitizing hepatocytes to death induced by Fas activation. However, in the exact inflammatory response, besides TNF-α, many other mediators, that might modulate apoptotic response differentially, are released. To resolve the issue, we studied the effects of lipopolysaccharide (LPS), one of the crucial inductors of inflammation in the liver, on apoptotic outcome. We show that LPS-induced inflammation diminishes the sensitivity of hepatocytes to Fas stimulus in vivo at caspase-8 level. Analysis of molecular mechanisms revealed an increased expression of various pro-inflammatory cytokines in non-parenchymal liver cells and hepatocyte-specific increase in Bcl-xL, associated with signal transducer and activator of transcription 3 (Stat3) phosphorylation. Pre-treatment with ruxolitinib, a selective Janus kinase (JAK) 1/2 inhibitor, prevented the LPS-induced Stat3 phosphorylation and restored the sensitivity of hepatocytes to Fas-mediated apoptosis. Furthermore, ruxolitinib pre-treatment diminished the LPS-induced Bcl-xL up-regulation without an inhibitory effect on LPS-induced expression of pro-inflammatory cytokines. In summary, although the reports are showing that the effects of isolated pro-inflammatory mediators, such as TNF-α or neutrophils, are pro-apoptotic, the overall effect of inflammatory milieu on hepatocytes in vivo is Stat3-dependent desensitization to Fas-mediated apoptosis.


Assuntos
Inflamação/tratamento farmacológico , Pirazóis/farmacologia , Fator de Transcrição STAT3/genética , Fator de Necrose Tumoral alfa/genética , Receptor fas/genética , Animais , Apoptose/efeitos dos fármacos , Caspase 8/genética , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Humanos , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Nitrilas , Pirimidinas , Fator de Transcrição STAT3/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Proteína bcl-X/genética
2.
Artigo em Inglês | MEDLINE | ID: mdl-31690176

RESUMO

An adequate level of low molecular weight thiols (LMW-SH, especially glutathione (GSH)) protects cellular macromolecules against toxic agents, and is used as a sensitive biomarker of exposure to toxic compounds. During sample collection, storage and preparation, non-enzymatic and enzymatic oxidation of LMW-SH can occur leading to analytical inaccuracy. The aim of this study was to optimize a fast and reliable screening method for the determination of LMW-SH, mainly GSH, in blood and plasma samples as well as to investigate the impact of storage conditions on the LMW-SH stability. Based on our results, the described spectrophotometric method allows fast and reliable determination of LMW-SH in blood and plasma samples. Results on incubation of samples at 37 °C imply that synthesis of LMW-SH (probably GSH) as well as dynamic interexchange among various thiols forms can be induced in blood cells in in vitro conditions. Importantly, the level of LMW-SH in blood and plasma stored at -20 °C was constant, indicating that they can be stored at -20 °C for at least 30 days. Therefore, the method is suitable for assessment of LMW-SH in long-term human biomonitoring as well as environmental field studies, especially those involving a large number of samples such as epidemiological studies.


Assuntos
Monitoramento Biológico/métodos , Compostos de Sulfidrila/sangue , Biomarcadores/sangue , Biomarcadores/química , Glutationa/sangue , Glutationa/química , Humanos , Peso Molecular , Oxirredução , Manejo de Espécimes , Compostos de Sulfidrila/química , Temperatura
3.
Nutr Cancer ; 71(7): 1078-1085, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30945952

RESUMO

25-Hydroxyvitamin D (25-OHD) may have a prognostic value in colorectal cancer (CRC) patients. However, as 25-OHD concentration is strongly impacted by surgery, it is uncertain what is the most reliable time-point for 25-OHD assessment, pre- or post-operative. Therefore, we examined 515 CRC patients (AJCC I-III) who underwent surgery. Blood samples were collected either pre-operatively (n = 286; median = 1 day before surgery) or post-operatively (n = 229; median = 8 days). Serum 25-OHD concentration was determined by liquid chromatography-tandem mass spectrometry. Association between 25-OHD and survival was tested in the whole cohort, followed by stratified analyses in pre- and post-operatively sampled. Median 25-OHD in the cohort was 36.7 nmol/L and median follow-up time was 5.9 years. There were no differences between pre- and post-operative cohort in age, sex, 25-OHD, AJCC stage, or localization of tumor. After adjustment, higher 25-OHD (>50 nmol/L) was associated with better overall survival only in post-operative (HR = 0.53; 95% CI: 0.33-0.84; P = 0.006), but not in pre-operative cohort (HR = 1.13; 95% CI: 0.77-1.65; P = 0.53). In conclusion, higher post-operative 25-OHD levels were associated with better survival outcome in CRC patients, while no such association was found for pre-operative levels. Time-point of blood collection should be addressed carefully in future research as it might affect the prognostic value of 25-OHD in CRC.


Assuntos
Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/cirurgia , Vitamina D/análogos & derivados , Idoso , Estudos de Coortes , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Período Pré-Operatório , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Vitamina D/sangue
4.
Int J Mol Sci ; 20(9)2019 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-31035335

RESUMO

The purpose of this paper was to outline the development of short peptide targeting of the human prostate specific antigen (hPSA), and to evaluate its effectiveness in staining PSA in human prostate cancer tissue. The targeting of the hPSA antigen by means of antisense peptide AVRDKVG was designed according to a three-step method involving: 1. The selection of the molecular target (hPSA epitope), 2. the modeling of an antisense peptide (paratope) based on the epitope sequence, and 3. the spectroscopic evaluation of sense-antisense peptide binding. We then modified standard hPSA immunohistochemical staining practice by using a biotinylated antisense peptide instead of the standard monoclonal antibody and compared the results of both procedures. Immunochemical testing on human tissue showed the applicability of the antisense peptide technology to human molecular targets. This methodology represents a new approach to deriving peptide ligands and potential lead compounds for the development of novel diagnostic substances, biopharmaceuticals and vaccines.


Assuntos
Biomarcadores Tumorais/imunologia , Peptídeos/imunologia , Antígeno Prostático Específico/imunologia , Neoplasias da Próstata/imunologia , Humanos , Imuno-Histoquímica , Masculino , Nanomedicina/métodos , Estrutura Secundária de Proteína
5.
Croat Med J ; 59(6): 290-297, 2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30610771

RESUMO

AIM: To evaluate the impact of pharmacotherapeutic education on 30-day post-discharge medication adherence and adverse outcomes in patients with type 2 diabetes mellitus (T2DM). METHODS: The prospective, randomized, single-center study was conducted at the Medical Department of University Hospital Dubrava, Zagreb, between April and June 2018. One hundred and thirty adult patients with T2DM who were discharged to the community were randomly assigned to either the intervention or the control group. Both groups during the hospital stay received the usual diabetes education. The intervention group received additional individual pre-discharge pharmacotherapeutic education about the discharge prescriptions. Medication adherence and occurrence of adverse outcomes (adverse drug reactions, readmission, emergency department visits, and death) were assessed at the follow-up visit, 30 days after discharge. RESULTS: The number of adherent patients was significantly higher in the intervention group (57/64 [89.9%] vs 41/61 [67.2%]; χ2 test, P=0.003]. There was no significant difference between the groups in the number of patients who experienced adverse outcomes (31/64 [48.4%] vs 36/61 [59.0%]; χ2 test, P=0.236). However, higher frequencies of all adverse outcomes were consistently observed in the control group. CONCLUSION: Pharmacotherapeutic education of patients with T2DM can significantly improve 30-day post-discharge medication adherence, without a significant reduction in adverse clinical outcomes. ClinicalTrial.gov identification number: NCT03438162.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Adesão à Medicação , Educação de Pacientes como Assunto , Idoso , Feminino , Humanos , Hipoglicemiantes/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
6.
Int J Mol Sci ; 15(6): 9209-23, 2014 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-24865486

RESUMO

Antisense peptide technology is a valuable tool for deriving new biologically active molecules and performing peptide-receptor modulation. It is based on the fact that peptides specified by the complementary (antisense) nucleotide sequences often bind to each other with a higher specificity and efficacy. We tested the validity of this concept on the example of human erythropoietin, a well-characterized and pharmacologically relevant hematopoietic growth factor. The purpose of the work was to present and test simple and efficient three-step procedure for the design of an antisense peptide targeting receptor-binding site of human erythropoietin. Firstly, we selected the carboxyl-terminal receptor binding region of the molecule (epitope) as a template for the antisense peptide modeling; Secondly, we designed an antisense peptide using mRNA transcription of the epitope sequence in the 3'→5' direction and computational screening of potential paratope structures with BLAST; Thirdly, we evaluated sense-antisense (epitope-paratope) peptide binding and affinity by means of fluorescence spectroscopy and microscale thermophoresis. Both methods showed similar Kd values of 850 and 816 µM, respectively. The advantages of the methods were: fast screening with a small quantity of the sample needed, and measurements done within the range of physicochemical parameters resembling physiological conditions. Antisense peptides targeting specific erythropoietin region(s) could be used for the development of new immunochemical methods. Selected antisense peptides with optimal affinity are potential lead compounds for the development of novel diagnostic substances, biopharmaceuticals and vaccines.


Assuntos
Eritropoetina/metabolismo , Peptídeos/química , Peptídeos/farmacologia , Sequência de Aminoácidos , Sítios de Ligação , Eritropoetina/química , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Peptídeos/genética , Ligação Proteica , Conformação Proteica , RNA Mensageiro/genética , Espectrometria de Fluorescência , Transcrição Gênica
7.
Molecules ; 19(8): 11833-45, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-25105920

RESUMO

Recent histopathological investigations in patients with hepatitis suggested possible involvement of Met-enkephalin and its receptors in the pathophysiology of hepatitis. Consequently, we evaluated the potential hepatoprotective effects of this endogenous opioid pentapeptide in the experimental model of acetaminophen induced hepatotoxicity in male CBA mice. Met-enkephalin exhibited strong hepatoprotective effects in a dose of 7.5 mg/kg, which corresponds to the protective dose reported for several different animal disease models. In this group plasma alanine aminotransferase and aspartate aminotransferase enzyme activities, as well as liver necrosis score were significantly reduced in comparison to control animals treated with physiological saline (p>0.01). The specificity of the peptide hepatoprotection was investigated from the standpoint of the receptor and peptide blockade. It was concluded that Met-enkephalin effects on the liver were mediated via δ and ζ opioid receptors. Genotoxic testing of Met-enkephalin confirmed the safety of the peptide.


Assuntos
Acetaminofen/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Encefalina Metionina/administração & dosagem , Fígado/efeitos dos fármacos , Animais , Doença Hepática Induzida por Substâncias e Drogas/patologia , Humanos , Fígado/patologia , Camundongos , Substâncias Protetoras/administração & dosagem
8.
Biochem Med (Zagreb) ; 34(1): 030701, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38125616

RESUMO

Introduction: Paraoxonase 1 (PON1) is the enzyme that removes carcinogenic radicals from lipids. The aim of the study was to investigate the differences in PON1 activity and oxidation stress parameters between patients with cervical intraepithelial neoplasia (CIN) and healthy controls. Materials and methods: The study included 65 women with CIN and 109 healthy women. Lipid parameters were determined on Cobas Integra 400 plus (Roche, Mannheim, Germany). Tiols and reduced glutathione (GSH) were determined spectrophotometric using Eliman reagent. Activity of PON1 was assessed with two substrates, paraoxon and phenylacetate by spectrophotometric method. Malondialdehyde (MDA) was determined by high performance liquid chromatography (Shimadzu Corporation, Kyoto, Japan). Mann-Whitney-test, t-test, χ2-test, correlation and logistic regression was used in statistical analysis. P < 0.05 was considered statistically significant. Results: The basal (P = 0.929) and NaCl-stimulated (P = 0.985) PON1 activity and activities standardised on the concentration of high-density lipoprotein (HDL; P = 0.076; P = 0.065, respectively) and apolipoprotein AI (apo AI; P = 0.444; P = 0.499, respectively) as well as PON1 phenotypes (P = 0.842) did not differ significantly between the groups. The PON1 arylesterase activity (53±19 kU/L vs. 77±17 kU/L; P < 0.001) and HDL-standardized activity (37 (28-44) kU/mmol vs. 43 (37-50) kU/mmol; P < 0.001) and apoAI (29±11 kU/g vs. 44±11 kU/g; P < 0.001) was significantly reduced in the CIN group. The concentration of the thiol groups was similar (P = 0.519), of MDA was lower (0.39 (0.27-0.55) µmol/L vs. 0.76 (0.57-1.15) µmol/L; P < 0.001) and of GSH was higher (112.0 (66.0-129.6) µg/mL vs. 53.4 (34.8-134.4) µg/mL; P < 0.001) in the CIN group. Conclusion: Reduced PON1 arylesterase activity, lower MDA and higher GSH concentration were observed in CIN patients.


Assuntos
Arildialquilfosfatase , Displasia do Colo do Útero , Humanos , Feminino , Arildialquilfosfatase/genética , Arildialquilfosfatase/metabolismo , Hidrolases de Éster Carboxílico , Estresse Oxidativo
9.
Nanoscale ; 16(19): 9412-9425, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38650478

RESUMO

Nanotechnology has the potential to provide formulations of antitumor agents with increased selectivity towards cancer tissue thereby decreasing systemic toxicity. This in vivo study evaluated the potential of novel nanoformulation based on poly(lactic-co-glycolic acid) (PLGA) to reduce the cardiotoxic potential of doxorubicin (DOX). In vivo toxicity of PLGADOX was compared with clinically approved non-PEGylated, liposomal nanoformulation of DOX (LipoDOX) and conventional DOX form (ConvDOX). The study was performed using Wistar Han rats of both sexes that were treated intravenously for 28 days with 5 doses of tested substances at intervals of 5 days. Histopathological analyses of heart tissues showed the presence of myofiber necrosis, degeneration processes, myocytolysis, and hemorrhage after treatment with ConvDOX, whereas only myofiber degeneration and hemorrhage were present after the treatment with nanoformulations. All DOX formulations caused an increase in the troponin T with the greatest increase caused by convDOX. qPCR analyses revealed an increase in the expression of inflammatory markers IL-6 and IL-8 after ConvDOX and an increase in IL-8 expression after lipoDOX treatments. The mass spectra imaging (MSI) of heart tissue indicates numerous metabolic and lipidomic changes caused by ConvDOX, while less severe cardiac damages were found after treatment with nanoformulations. In the case of LipoDOX, autophagy and apoptosis were still detectable, whereas PLGADOX induced only detectable mitochondrial toxicity. Cardiotoxic effects were frequently sex-related with the greater risk of cardiotoxicity observed mostly in male rats.


Assuntos
Cardiotoxicidade , Doxorrubicina , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos Wistar , Doxorrubicina/química , Doxorrubicina/farmacologia , Doxorrubicina/análogos & derivados , Animais , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Ratos , Masculino , Cardiotoxicidade/prevenção & controle , Feminino , Apoptose/efeitos dos fármacos , Nanopartículas/química , Miocárdio/patologia , Miocárdio/metabolismo , Polietilenoglicóis/química , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Coração/efeitos dos fármacos , Lipossomos/química
10.
Acta Pharm ; 73(4): 691-708, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38147472

RESUMO

The aim of this study was to compare the effects of dexmedetomidine and dexamethasone as adjuvants to preoperative epidural administration of local anesthetic (ropivacaine) in thoracic surgery on the postoperative level of pain, use of analgesics, inflammation, and oxidative stress. The study enrolled 42 patients who underwent elective thoracic surgery in a one-year period at the University Hospital Dubrava (Zagreb, Croatia). Based on a computer-generated randomization list the patients were assigned to the dexmedetomidine (n = 18) or dexamethasone (n = 24) group. Postoperatively, patients of dexmedetomidine group reported lower pain (VAS value 1 h post surgery, 3.4 ± 2.7 vs. 5.4 ± 1.8, dexmedetomidine vs. dexamethasone, p < 0.01) and had lower anal-gesic requirements in comparison with dexamethasone group. Thus, dexmedetomidine in comparison with dexamethasone was more efficient in lowering pain and analgesia requirements 24 h after the surgery. On the contrary, dexamethasone had better anti-inflammatory properties (CRP level 24 h post surgery, 131.9 ± 90.7 vs. 26.0 ± 55.2 mg L-1, dexmedetomidine vs. dexamethasone, p < 0.01). Both dexmedetomidine and dexamethasone exhibited antioxidant effects, however, their antioxidant properties should be further explored. The results of this study improve current knowledge of pain control in thoracic surgery.


Assuntos
Dexmedetomidina , Cirurgia Torácica , Humanos , Analgésicos , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Dexametasona , Estresse Oxidativo , Inflamação/tratamento farmacológico , Inflamação/prevenção & controle
11.
Molecules ; 17(10): 11680-92, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23027369

RESUMO

Recently discovered anti-inflammatory and immunomodulatory properties of melanocortin peptides led to the conclusion that they might serve as new anti-inflammatory therapeutics. The purpose of this work was to examine the effectiveness of ß-melanocortin (ß-MSH) in two experimental models: ethanol-induced gastric lesions and TNBS (2,4,6-trinitrobenzenesulfonic acid)-induced colitis in male Wistar rats. Three progressive doses of ß-MSH were used: 0.125, 0.250 and 0.500 mg/kg. Our results suggest that ß-MSH acts as a protective substance in the gastric lesions model, which can be seen as a statistically significant reduction of hemorrhagic lesions at all three doses, compared to the control group. The most efficient dose was 0.250 mg/kg. Statistically significant reduction in mucosal surface affected by necrosis and the reduction of overall degree of inflammation in the colitis model indicates an anti-inflammatory effect of ß-MSH at a dose of 0.250 mg/kg. The results justify further research on ß-MSH peptide and its derivates in the inflammatory gastrointestinal diseases, and point out the possibility of using ß-MSH in studies of digestive system pharmacology.


Assuntos
Trato Gastrointestinal/efeitos dos fármacos , Melanocortinas/farmacologia , Substâncias Protetoras/farmacologia , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/patologia , Colo/efeitos dos fármacos , Colo/patologia , Modelos Animais de Doenças , Gastrite/induzido quimicamente , Gastrite/tratamento farmacológico , Gastrite/patologia , Inflamação/tratamento farmacológico , Inflamação/patologia , Masculino , Melanocortinas/administração & dosagem , Melanocortinas/uso terapêutico , Necrose/tratamento farmacológico , Necrose/patologia , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/uso terapêutico , Ratos , Ratos Wistar
12.
Arh Hig Rada Toksikol ; 73(1): 48-61, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35390238

RESUMO

Ferritin is the main intracellular storage of iron. Animal studies show that female liver and kidney express more ferritin and accumulate more iron than male. However, no study so far has investigated sex and age differences in light (FtL) and heavy (FtH) ferritin chain expression. To address this, we relied on specific antibodies and immunochemical methods to analyse the expression of both ferritin chains in the liver and kidney of 3-month and 2-year-old male and female Wistar rats. To see how sex hormones may affect expression we also studied adult animals gonadectomised at the age of 10 weeks. FtL and FtH were more expressed in both organs of female rats, while gonadectomy increased the expression in males and decreased it in females, which suggests that it is stimulated by female and inhibited by male steroid hormones. Normal kidney ferritin distribution and change with aging warrant more attention in studies of (patho) physiological and toxicological processes.


Assuntos
Apoferritinas , Ferritinas , Envelhecimento , Animais , Apoferritinas/metabolismo , Castração , Feminino , Ferritinas/metabolismo , Ferro , Rim/metabolismo , Fígado/metabolismo , Fígado/cirurgia , Masculino , Ratos , Ratos Wistar , Caracteres Sexuais
13.
Chem Biol Interact ; 368: 110225, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36280157

RESUMO

Increasing use of nano-enabled products provides many benefits in various industrial processes and medical applications, but it also raises concern about release of nanoparticles (NPs) into the environment and subsequent human exposure. While potential toxicity of individual NPs types has been well described in scientific literature, exposure and health-related effects of nanomixtures has been poorly described. This study aimed to evaluate the combined effect of silver (AgNP) and polystyrene NPs (PSNP) on the human macrophages. AgNP are one of the most commercialized NPs due to efficient antimicrobial activity, while PSNP are ubiquitous in terrestrial and aquatic environments due to plastic pollution and degradation of polystyrene-based products. Differentiated monocytic cell line THP-1 were used as an in vitro model of human macrophages. Multiple aspects of cellular response to AgNP-PSNP nanomixture were analyzed including cell death, induction of apoptosis, oxidative stress response, expression of pro- and anti-inflammatory cytokines, and nanomechanical properties of cells. NPs uptake was visualized by confocal microscopy and quantified using flow cytometry. Results show that nanomixture increased apoptosis and cell death, expression of IL-6, IL-8 and TNFa, oxidative stress and mitochondrial dysfunction in cells compared to AgNP and PSNP applied as single treatments, indicating mixture additive action. Anti-inflammatory cytokines IL1b, IL-4 and IL-10 were not affected by combined exposure compared to single NPs. Visualization of NPs uptake and internalization showed that AgNP and PSNP were localized mostly in cytoplasm, with small fraction of AgNP translocated into cell nuclei, which explain increased number of double-stranded DNA breaks following exposure of cells to AgNPs alone or in the mixture. Study outcomes represent clear warnings on the human co-exposure to AgNP and PSNP that needs to be implemented in risk assessment approaches towards toxic-free environment.


Assuntos
Nanopartículas Metálicas , Prata , Humanos , Prata/toxicidade , Poliestirenos/toxicidade , Nanopartículas Metálicas/toxicidade , Macrófagos , Apoptose
14.
Biomedicines ; 10(5)2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35625945

RESUMO

The available treatments for cholestatic liver fibrosis are limited, and the disease often progresses to liver cirrhosis. Tamoxifen is a selective modulator of estrogen receptors, commonly used in breast cancer therapy. A recent in vitro study showed that tamoxifen deactivates hepatic stellate cells, suggesting its potential as an antifibrotic therapeutic, but its effects in vivo remain poorly investigated. In the present study, we show that tamoxifen protects against the cholestatic fibrosis induced by a diet supplemented with 0.025% 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC). Mice fed with a DDC-supplemented diet for four weeks and treated with tamoxifen developed a significantly milder degree of liver fibrosis than vehicle-treated mice, as evidenced by a lower percentage of Sirius red-stained area (60.4% decrease in stained area in male and 42% decrease in female mice, p < 0.001 and p < 0.01, respectively) and by lower hydroxyproline content. The finding was further confirmed by qPCR analysis, which showed a lower expression of genes for Col1a1, Acta2, Sox9, Pdgf, and Krt19, indicating the inhibitory effect on hepatic stellate cells, collagen production, and biliary duct proliferation. The degree of protection was similar in male and female mice. Tamoxifen per se, injected into standard-diet-fed mice, increased the expression of genes for Il6 (p < 0.01 and p < 0.001 in male and female mice, respectively) and Tgfß (p < 0.01 for both sexes), and had no adverse effects. We showed that tamoxifen sex-independently protects against cholestatic DDC-induced liver fibrosis. The increased expression of Il6 and Tgfß seems to be a plausible protective mechanism that should be the primary focus of further research.

15.
J Trace Elem Med Biol ; 73: 127004, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35617720

RESUMO

BACKGROUND: Silver nanoparticles (AgNP) are one of the most commercialized types of nanomaterials, with a wide range of applications owing to their antimicrobial activity. They are particularly important in hospitals and other healthcare settings, where they are used to maintain sterility of surfaces, textiles, catheters, medical implants, and more. However, AgNP can not only harm bacteria, but also damage mammalian cells and tissue. While the potential toxicity of AgNP is an understood risk, there is a lack of data on their toxicity in combination with polymeric materials, especially plastic nanoparticles such as polystyrene nanoparticles (PSNP) that can be released from surfaces of polystyrene devices during their medical use. AIM: This study aimed to investigate combined effect of AgNP and nanoplastics on human immune response. METHODS: Cells were treated with a range of PSNP and AgNP concentrations, either applied alone or in combination. Cytotoxicity, induction of apoptosis, generation of oxidative stress, uptake efficiency, intracellular localization and nanomechanical cell properties were selected as exposure biomarkers. RESULTS: Collected experimental data showed that nanomixture induced oxidative stress, apoptosis and mortality of Jurkat cells stronger than its individual components. Cell treatment with AgNP/PSNP mixture also significantly changed cell mechanical properties, evidenced by reduction of cells' Young Modulus. CONCLUSION: AgNP and PSNP showed additive toxic effects on immortalized human lymphocytes, evidenced by increase in cellular oxidative stress, induction of apoptosis, and reduction of cell stiffness. These results have important implications for using AgNP and PSNP in medical contexts, particularly for long-term medical implants.


Assuntos
Nanopartículas Metálicas , Prata , Animais , Humanos , Células Jurkat , Mamíferos , Nanopartículas Metálicas/toxicidade , Microplásticos , Poliestirenos/toxicidade , Prata/toxicidade
16.
Healthcare (Basel) ; 10(12)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36553960

RESUMO

Low-grade squamous intraepithelial lesion (SIL) is a cytologic diagnosis etiologically related to human papilloma virus (HPV) infection that leads to the release of inflammation mediators, the formation of reactive oxygen species (ROS) and decreased levels of antioxidants in tissues, which is why antioxidants might be considered effective against SIL progression. This randomized double-blind placebo-controlled study aimed to investigate the effectiveness of alpha-lipoic acid (ALA) supplementation (600 mg/day) on the regression of low-grade SIL in 100 patients. Low-grade SIL was determined after the cytological screening, colposcopic examination and targeted biopsy and histological confirmation of cytological−colposcopic diagnosis. Inflammation parameters and the presence of HPV were determined by standard laboratory methods. Dietary and lifestyle habits were investigated using a standardized and validated semi-quantitative food questionnaire (FFQ). ALA supplementation significantly reduced the proportion of patients with low-grade cytological abnormalities, in comparison to placebo. Given the obtained level of significance (p < 0.001), the presented results indicate that short-term ALA supplementation shows a clinically significant effect on cervical cytology. Future studies should focus on the use of innovative formulations of ALA that might induce bioavailability and therapeutic efficiency against HPV infection and the investigation of synergistic effects of concurrent dietary/lifestyle modification and ALA supplementation in both low-grade and high-grade SIL.

17.
Molecules ; 16(9): 7331-43, 2011 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-21873934

RESUMO

The genetic code defines nucleotide patterns that code for individual amino acids and their complementary, i.e., antisense, pairs. Peptides specified by the complementary mRNAs often bind to each other with a higher specificity and efficacy. Applications of this genetic code property in biomedicine are related to the modulation of peptide and hormone biological function, selective immunomodulation, modeling of continuous and linear epitopes, modeling of mimotopes, paratopes and antibody mimetics, peptide vaccine development, peptidomimetic and drug design. We have investigated sense-antisense peptide interactions and related modulation of the peptide function by modulating the effects of a-MSH on hepatoprotection with its antisense peptide LVKAT. First, transcription of complementary mRNA sequence of a-MSH in 3'→5' direction was used to design antisense peptide to the central motif that serves as a-MSH pharmacophore for melanocortin receptors. Second, tryptophan spectrofluorometric titration was applied to evaluate the binding of a-MSH and its central pharmacophore motif to the antisense peptide, and it was concluded that this procedure represents a simple and efficient method to evaluate sense-antisense peptide interaction in vitro. Third, we showed that antisense peptide LVKAT abolished potent hepatoprotective effects of a-MSH in vivo.


Assuntos
Citoproteção/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Oligopeptídeos/química , alfa-MSH/química , Acetaminofen , Alanina Transaminase/sangue , Sequência de Aminoácidos , Animais , Elementos Antissenso (Genética) , Aspartato Aminotransferases , Doença Hepática Induzida por Substâncias e Drogas/patologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Código Genético , Hepatócitos/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos CBA , Necrose/induzido quimicamente , Oligopeptídeos/genética , Oligopeptídeos/farmacologia , Ligação Proteica , alfa-MSH/farmacologia
18.
Acta Med Croatica ; 65(2): 111-8, 2011.
Artigo em Servo-Croata (Latino) | MEDLINE | ID: mdl-22359876

RESUMO

Emergencies in allergology and clinical immunology are quite common and pose a public health problem in Croatia and worldwide. Allergic reactions ranging from mild symptoms such as pruritus to generalized skin eruptions, gastrointestinal and respiratory symptoms to anaphylaxis with cardiovascular emergencies are very common. Reaction develops to inhalant substances, food and food ingredients, various foreign substances (blood, latex, etc.) and many other well known antigens and drugs which are frequent causes of anaphylactic reactions, asthma, generalized urticaria, angioedema. There are 35 different skin reactions induced by drugs through immune complexes, complement mediated reactions and direct histamine liberation (by opiates or dextran) and modulators of arachidonic acid metabolism (such as NSAID). Along with painful infiltrates, insect venom allergy manifests with disseminated exanthema and angioedema. Current diagnostic methods, especially therapeutic procedures for emergencies in concordance with the international consensus of the European Allergy White Paper, require the same procedure in clinical practice. Many patients with different allergic skin diseases are treated inappropriately, some are tested in active phase of the disease, during anti-allergic therapy, and some are administered corticosteroids and antihistamines longer than necessary. Sometimes, the treatment of emergencies requires a person experienced in intensive care medicine. However, any physician might be responsible for the treatment of acute symptoms in his office, and thus has to know the modalities and relevant drugs and treatment essentials. Anaphylactic reactions are rare, but every physician should be prepared for the worst. Due knowledge of the correct management should be a must for all of us. The most common emergencies require emergency treatment and diagnostic procedures upon disease regression.


Assuntos
Hipersensibilidade Imediata/diagnóstico , Hipersensibilidade Imediata/terapia , Doença Aguda , Anafilaxia/diagnóstico , Anafilaxia/terapia , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/terapia , Emergências , Humanos , Hipersensibilidade Imediata/etiologia
19.
Diagnostics (Basel) ; 11(12)2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34943512

RESUMO

Current guidelines advocate 3-4 passes with a fine-needle aspiration (FNA) to achieve high rates of diagnostic samples for malignancy when performing endoscopic ultrasound (EUS)-guided sampling of solid pancreatic lesions, in the absence of on-site cytologic evaluation. The aim of this study is to compare 2 vs. 3 needle passes in EUS-FNA for solid pancreatic lesions in terms of incremental diagnostic yield and to identify factors associated with the procedure's outcome. In this retrospective study, 2 passes of EUS-FNA were found to have similar diagnostic yield compared to 3 passes for the diagnosis of solid pancreatic masses, suggesting that there might be no significant incremental tissue yield when 3 passes are performed.

20.
Molecules ; 15(3): 1232-41, 2010 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-20335976

RESUMO

Research over the past decade has indicated that melanocortin peptides are potent inhibitors of inflammation and a promising source of new anti-inflammatory and cytoprotective therapies. The purpose of the present paper is to compare protective effects of alpha-, beta-, and gamma-melanocyte stimulating hormone on acetaminophen induced liver lesions in male CBA mice. Acetaminophen was applied intragastrically in a dose of 150 mg/kg, and tested substances were applied intraperitoneally 1 hour before acetaminophen. Mice were sacrificed after 24 hours and intensity of liver injury was estimated by measurement of plasma transaminase activity (AST and ALT) and histopathological grading of lesions. It was found that alpha-, beta-, and gamma-MSH decrease intensity of lesions by both criteria in a dose-dependent manner.


Assuntos
Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , alfa-MSH/farmacologia , beta-MSH/farmacologia , gama-MSH/farmacologia , Hormônio Adrenocorticotrópico/química , Alanina Transaminase/sangue , Sequência de Aminoácidos , Animais , Aspartato Aminotransferases/sangue , Doença Hepática Induzida por Substâncias e Drogas/enzimologia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Relação Dose-Resposta a Droga , Masculino , Camundongos , Camundongos Endogâmicos CBA , Dados de Sequência Molecular , alfa-MSH/química , beta-MSH/química , gama-MSH/química
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