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1.
Ecotoxicol Environ Saf ; 202: 110953, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800227

RESUMO

Heavy metal acclimated bacteria are profoundly the preferred choice for bioremediation studies. Bacteria get acclimated to toxic concentrations of heavy metals by induction of specific enzymes and genetic selection favoring new metabolic abilities leading to activation of one or several of resistance mechanisms creating bacterial populations with differences in resistance profile and/or level. Therefore, to use in bioremediation processes, it is important to discriminate acclimated bacterial populations and choose a more resistant strain. In this study, we discriminated heavy metal acclimated bacteria by using Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy and multivariate analysis methods namely Hierarchical Cluster Analysis (HCA), Principal Component Analysis (PCA) and Soft Independent Modeling of Class Analogy (SIMCA). Two acclimation methods, acute and gradual, were used which cause differences in molecular changes resulting in bacterial populations with different molecular and resistance profiles. Brevundimonas sp., Gordonia sp., and Microbacterium oxydans were exposed to the toxic concentrations of Cd (30 µg/ml) or Pb (90 µg/ml) by using broth medium as a growth media. Our results revealed that PCA and HCA clearly discriminated the acute-acclimated, gradual-acclimated, and control bacteria from each other in protein, carbohydrate, and whole spectral regions. Furthermore, we classified acclimated (acute and gradual) and control bacteria more accurately by using SIMCA with 99.9% confidence. This study demonstrated that heavy metal acclimated and control group bacteria can be discriminated by using chemometric analysis of FTIR spectra in a powerful, cost-effective, and handy way. In addition to the determination of the most appropriate acclimation procedure, this approach can be used in the detection of the most resistant bacterial strains to be used in bioremediation studies.


Assuntos
Aclimatação/efeitos dos fármacos , Actinobacteria/efeitos dos fármacos , Caulobacteraceae/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Metais Pesados/toxicidade , Actinobacteria/crescimento & desenvolvimento , Biodegradação Ambiental , Caulobacteraceae/crescimento & desenvolvimento , Análise por Conglomerados , Meios de Cultura , Microbacterium , Análise Multivariada , Análise de Componente Principal , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Biochim Biophys Acta ; 1858(4): 845-54, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26850735

RESUMO

Diabetic kidney disease (DKD) is a dominant factor standing for kidney impairments during diabetes. In this study, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy was used to disclose the diabetes-induced structural changes in the kidney and evaluate the effects of selenium on diabetes. The increase in the area of the olefinic band indicated increased amount of lipid peroxidation end products in diabetic kidney brush border cell membrane. Moreover, saturated lipid content of this cell membrane considerably diminished. DKD was found to disrupt lipid order and cause a decrease in membrane dynamics. However, the administration of selenium at low and medium doses was shown to improve these conditions by changing the lipid contents toward control values, restoring the ordered structure of the lipids and membrane dynamics. Curve-fitting and artificial neural network (ANN) analyses of secondary structures of proteins demonstrated a relative increase in α-helix and reduction in the ß-sheet during diabetes in comparison to the control group, which were ameliorated following selenium treatment at low and medium doses. These findings were further confirmed by applying hierarchical cluster analysis (HCA) and principal component analysis (PCA). A clear separation of the experimental groups was obtained with high heterogeneity in the lipid and protein regions. These chemometric analyses showed that the low and medium doses of selenium-treated diabetic groups are successfully segregated from the diabetic group and clustered closer to the control. The study suggests that medium and, more predominantly, low-dose selenium treatment can be efficient in eliminating diabetes-induced structural alterations.


Assuntos
Membrana Celular/química , Diabetes Mellitus Experimental/tratamento farmacológico , Microvilosidades/química , Selênio/administração & dosagem , Animais , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Diabetes Mellitus Experimental/patologia , Humanos , Rim/química , Rim/efeitos dos fármacos , Rim/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Microvilosidades/efeitos dos fármacos , Ratos
3.
Biochim Biophys Acta ; 1838(12): 3088-96, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25194682

RESUMO

Epilepsy is characterized by disruption of balance between cerebral excitation and inhibition, leading to recurrent and unprovoked convulsions. Studies are still underway to understand mechanisms lying epileptic seizures with the aim of improving treatment strategies. In this context, the research on brain tissue membranes gains importance for generation of epileptic activities. In order to provide additional information for this field, we have investigated the effects of pentylenetetrazol-induced and audiogenetically susceptible epileptic seizures on structure, content and function of rat brain membrane components using Fourier transform infrared (FT-IR) spectroscopy. The findings have shown that both two types of epileptic seizures stimulate the variations in the molecular organization of membrane lipids, which have potential to influence the structures in connection with functions of membrane proteins. Moreover, less fluid lipid structure and a decline in content of lipids obtained from the ratio of CH3 asym/lipid, CH2 asym/lipid, CO/lipid, and olefinicCH/lipid and the areas of the PO2 symmetric and asymmetric modes were observed. Moreover, based on IR data the changes in the conformation of proteins were predicted by neural network (NN) analysis, and displayed as an increase in random coil despite a decrease in beta sheet. Depending on spectral parameters, we have successfully differentiated treated samples from the control by principal component analysis (PCA) and cluster analysis. In summary, FT-IR spectroscopy may offer promising attempt to identify compositional, structural and functional alterations in brain tissue membranes resulting from epileptic activities.

4.
Biochim Biophys Acta ; 1838(11): 2798-806, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25091390

RESUMO

Depression is one of the most common psychiatric diseases in the population. Agomelatine is a novel antidepressant drug with melatonin receptor agonistic and serotonin 5-HT2C antagonistic properties. Furthermore, being a melatonergic drug, agomelatine has the potential of being used in therapeutic applications like melatonin as an antioxidant, anti-inflammatory and antiapoptotic drug. The action mechanism of agomelatine on the membrane structure has not been clarified yet. In the present study, we aimed to investigate the interaction of agomelatine with model membranes of dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylgylcerol (DPPG) by Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). We found that agomelatine interacts with the head group in such a manner that it destabilizes the membrane architecture to a large extent. Thus, agomelatine causes alterations in the order, packing and dynamics of the DPPC and DPPG model membranes. Our results suggest that agomelatine strongly interacts with zwitterionic and charged membrane phospholipids. Because lipid structure and dynamics may have influence on the structure of membrane bound proteins and affect the signal transduction systems of membranes, these effects of agomelatine may be important in its action mechanism.

5.
Biochim Biophys Acta ; 1840(1): 406-15, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24045089

RESUMO

BACKGROUND: Statins are the most commonly used drugs for the treatment of hypercholesterolemia. Their most frequent side effect is myotoxicity. To date, it remains unclear whether statins preferentially induce myotoxicity in fast- or in slow-twitch muscles. Therefore, we investigated these effects on fast- (extensor digitorum longus; EDL), slow- (soleus; SOL), and mixed-twitch muscles (diaphragm; DIA) in rats by comparing their contractile and molecular structural properties. METHODS: Simvastatin-induced functional changes were determined by muscle contraction measurements, and drug-induced molecular changes were investigated using Fourier transform infrared (FTIR) and attenuated total reflectance (ATR) FTIR spectroscopy. RESULTS: With simvastatin administration (30 days, 50mg/kg), a depression in the force-frequency curves in all muscles was observed, indicating the impairment of muscle contractility; however, the EDL and DIA muscles were affected more severely than the SOL muscle. Spectroscopic findings also showed a decrease in protein, glycogen, nucleic acid, lipid content and an increase in lipid order and lipid dynamics in the simvastatin-treated muscles. The lipid order and dynamics directly affect membrane thickness. Therefore, the kinetics and functions of membrane ion channels were also affected, contributing to the statin-induced impairment of muscle contractility. Furthermore, a reduction in α-helix and ß-sheet and an increase in random coil, aggregated and antiparallel ß-sheet were observed, indicating the protein denaturation. Spectral studies showed that the extent of molecular structural alterations in the muscles following simvastatin administration was in the order EDL>DIA>SOL. CONCLUSIONS: Simvastatin-induced structural and functional alterations are more profound in the fast-twitch than in the slow-twitch muscles. GENERAL SIGNIFICANCE: Myotoxic effects of simvastatin are primarily observed in the fast-twitch muscles.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/toxicidade , Contração Muscular/efeitos dos fármacos , Fibras Musculares de Contração Rápida/patologia , Fibras Musculares de Contração Lenta/patologia , Músculo Esquelético/patologia , Doenças Musculares/patologia , Sinvastatina/toxicidade , Animais , Canais Iônicos/química , Canais Iônicos/metabolismo , Masculino , Fibras Musculares de Contração Rápida/efeitos dos fármacos , Fibras Musculares de Contração Lenta/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Doenças Musculares/induzido quimicamente , Ratos , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Anal Chem ; 87(19): 9653-61, 2015 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-26366586

RESUMO

Lead and cadmium are frequently encountered heavy metals in industrially polluted areas. Many heavy metal resistant bacterial strains have a high biosorption capacity and thus are good candidates for the removal of toxic metals from the environment. However, as of yet there is no accurate method for discrimination of highly adaptive bacterial strains among the populations present in a given habitat. In this study, we aimed to find distinguishing molecular features of lead and cadmium resistant bacteria using Attenuated Total Reflectance-Fourier Transformed Infrared (ATR-FT-IR) spectroscopy and chemometric approaches. Our results demonstrated that both control and metal exposed E. coli and S. aureus strains could be successfully discriminated from each other using hierarchical cluster and principal component analysis methods. Moreover, we found that lead exposed bacterial strains could be successfully discriminated from cadmium exposed ones with a high heterogeneity value. These clear discriminations can be described by the ability of a bacterium to change its metabolism in terms of the content and structure of cellular macromolecules under heavy metal stress. In our case, cadmium and lead-induced genetic response systems in bacteria caused remarkable alterations in overall cellular metabolism. Bacteria deal with a heavy metal stress by altering nucleic acid methylations and lipid and protein synthesis. Heavy metal burden led to the development of relevant metabolic changes in proteins, lipids, and nucleic acids of the resistant bacteria described in this study. Our approach showed that infrared spectra obtained via ATR-FT-IR spectroscopy coupled with chemometric analysis can be utilized for rapid, low-cost, informative, reliable, and operator-independent discrimination of resistant bacterial populations.


Assuntos
Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Metais Pesados/toxicidade , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/metabolismo , Análise por Conglomerados , Escherichia coli/genética , Metais Pesados/metabolismo , Análise de Componente Principal , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/genética
7.
Br J Nutr ; 113(1): 45-55, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25400158

RESUMO

To date, no structural study has been carried out on the effects of vitamin A deficiency (VAD) on hippocampal macromolecules. Therefore, in the present study, the effect of dietary VAD on the structure, content and function of rat hippocampal molecules was investigated using Fourier transform IF spectroscopy. Male Wistar rats were randomly divided into three groups: an experimental group maintained on a vitamin A-deficient liquid diet (VAD, n 7); a control group maintained on a vitamin A-supplemented liquid diet (CON, n 9); a pure control group maintained on standard solid laboratory chow (PC, n 7). The PC group was included in the study to ensure that the usage of liquid diet did not influence the outcomes of VAD. Both the CON and PC groups were successfully discriminated from the VAD group by principal component analysis and hierarchical cluster analysis. The spectral analysis indicated a significant decrease in the contents of saturated and unsaturated lipids, cholesteryl esters, TAG and nucleic acids in the VAD group when compared with the CON group (P≤ 0·05). In addition, a significant decrease in membrane fluidity and a significant increase in lipid order (e.g. acyl chain flexibility) were observed in the VAD group (P≤ 0·001). The results of the artificial neural network analysis revealed a significant decrease in the α-helix structure content and a significant increase in the turn and random coil structure contents, indicating protein denaturation, in the VAD group when compared with the CON and PC groups (P≤ 0·05). Dietary exclusion of vitamin A for 3 months apparently had an adverse impact on compositional, structural and dynamical parameters. These changes can be due to increased oxidative stress, confirming the antioxidant protection provided by vitamin A when used as a dietary supplement at low-to-moderate doses.


Assuntos
Hipocampo/patologia , Deficiência de Vitamina A/patologia , Animais , Análise por Conglomerados , Dieta , Relação Dose-Resposta a Droga , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Análise de Componente Principal , Ratos , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Vitamina A/farmacologia
8.
Analyst ; 140(7): 2205-14, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25692183

RESUMO

Obesity is a heterogeneous disorder which increases risks for multiple metabolic diseases, such as type 2 diabetes. The current study aims to characterize and compare visceral and subcutaneous adipose tissues in terms of macromolecular content and investigate transdifferentiation between white and brown adipocytes. Regarding this aim, Fourier transform infrared (FTIR) microspectroscopy and uncoupling protein 1 (UCP1) immunohistological staining were used to investigate gonadal (visceral) and inguinal (subcutaneous) adipose tissues of male Berlin fat mice inbred (BFMI) lines, which are spontaneously obese. The results indicated a remarkable increase in the lipid/protein ratio, accompanied with a decrease of UCP1 protein content which might be due to the transdifferentiation of brown adipocytes to white adipocytes in obese groups. It has been widely reported that brown adipose tissue has a strong effect on fatty acid and glucose homeostasis and it could provide an opportunity for the therapy of obesity. When the amount of brown adipose tissue was decreased, lower unsaturation/saturation ratio, qualitatively longer hydrocarbon acyl chain length of lipids and higher amount of triglycerides were obtained in both adipose tissues of mice lines. The results also revealed that subcutaneous adipose tissue was more prone to obesity-induced structural changes than visceral adipose tissue, which could originate from it possessing a lower amount of brown adipose tissue. The current study clearly revealed the power of FTIR microspectroscopy in the precise determination of obesity-induced structural and functional changes in inguinal and gonadal adipose tissue of mice lines.


Assuntos
Adipócitos Marrons/citologia , Adipócitos Brancos/citologia , Adiposidade , Transdiferenciação Celular , Gordura Intra-Abdominal/citologia , Imagem Óptica , Gordura Subcutânea/citologia , Adipócitos Marrons/metabolismo , Adipócitos Brancos/metabolismo , Animais , Gordura Intra-Abdominal/metabolismo , Masculino , Camundongos , Espectroscopia de Infravermelho com Transformada de Fourier , Gordura Subcutânea/metabolismo
9.
Anal Chem ; 86(3): 1395-403, 2014 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-24377319

RESUMO

To accomplish the appropriate treatment strategies of epilepsy action mechanisms underlying epileptic seizures should be lightened. The identification of epileptic seizure-induced alterations on the brain related to their pathologies may provide information for its action mechanism. Therefore, the current study determined molecular consequences of seizures induced by pentylenetetrazol (PTZ), which is a widely used convulsant agent, on rat brain. The rats were administered subconvulsant (25 mg/kg) and convulsant (60 mg/kg) doses of PTZ during a week, and brain tissues were studied by Fourier transform infrared (FT-IR) spectroscopy. Results revealed a decrease in lipid fluidity and lipid and protein content and also the differences in membrane packing by changing the nature of hydrogen bonding as indicated by the C═O, the PO(-)2 symmetric, and asymmetric bands. Monitoring of the olefinic band elicited seizure-induced lipid peroxidation further confirmed by the thiobarbituric acid (TBAR) assay. Additionally, PTZ-induced convulsions led to alterations in protein structures obtained by neural network (NN) predictions like an increase in random coils. On the basis of the spectral changes, treated samples could be successfully differentiated from the controls by cluster analysis. Consequently, the convulsive dose of PTZ caused more significant molecular variations compared to the subconvulsive one. All findings might have an important role in understanding the molecular mechanisms underlying epileptic activities.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Pentilenotetrazol/efeitos adversos , Convulsões/induzido quimicamente , Convulsões/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Animais , Encéfalo/fisiopatologia , Análise por Conglomerados , Relação Dose-Resposta a Droga , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Convulsões/fisiopatologia
10.
J Biophotonics ; 17(6): e202300541, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38531619

RESUMO

The aim of this study is to reveal the molecular changes accompanying the neuronal hyper-excitability during lipopolysaccharide (LPS)-induced systemic inflammation on rat hippocampus using Fourier transform infrared (FTIR) spectroscopy. For this aim, the body temperature of Wistar albino rats administered LPS or saline was recorded by radiotelemetry. The animals were decapitated when their body temperature began to decrease by 0.5°C after LPS treatment and the hippocampi of them were examined by FTIR spectroscopy. The results indicated that systemic inflammation caused lipid peroxidation, an increase in the amounts of lipids, proteins and nucleic acids, a decrease in membrane order, an increase in membrane dynamics and changes in the secondary structure of proteins. Principal component analysis successfully separated control and LPS-treated groups. In conclusion, significant structural, compositional and functional alterations occur in the hippocampus during systemic inflammation and these changes may have specific characteristics which can lead to neuronal hyper-excitability.


Assuntos
Hipocampo , Inflamação , Lipopolissacarídeos , Ratos Wistar , Animais , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/patologia , Lipopolissacarídeos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Ratos , Inflamação/induzido quimicamente , Inflamação/patologia , Masculino , Peroxidação de Lipídeos/efeitos dos fármacos
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 288: 122149, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36470089

RESUMO

Type I Diabetes is a multisystem disease that causes alterations in carbohydrate, protein, and fat metabolisms due to hyperglycemia. It has an extensive pathology, especially the mechanism involving oxidative stress is still complex. Type I diabetes is correlated with increased formation of free radicals and decreased levels of antioxidant potential. Vitamin C (Vit C) is a powerful antioxidant that participates in antioxidant defense, protecting lipid membranes and proteins from oxidative damage by donating electrons to free radicals. The effect of type I diabetes and the recovery role of Vit C on the structure and composition of the biomolecular content of testicular tissue is still unknown. Therefore, the current study aimed to investigate the alterations in the biomolecules of rat testes due to Streptozotocin (STZ)-induced type I diabetes using Attenuated Total Reflectance (ATR)-Fourier Transform Infrared (FTIR) spectroscopy and histological staining. The results revealed that the biomolecular structure and composition of testicular tissue are highly affected due to the development of diabetes. We obtained decreased saturation levels and increased unsaturation index in the lipids indicating the presence of lipid peroxidation in the diabetic state. The elevated lipid peroxidation levels have been implicated in the pathogenesis of naturally occurring and chemically induced diabetes. On the other hand, the protein content of diabetic rat testicular tissue was shown to decrease considerably, indicating an increase in proteolysis processes. Supporting the ratio of protein structural and conformational change, protein secondary structural components were also found to alter substantially in the diabetic state. Diabetes was also shown to lead to a decrease in the content of nucleic acids compared to proteins. These diabetes-induced alterations were found to be substantially recovered with the administration of Vit C. Although different doses and administration types of Vit C have been reported in the literature, there is no consensus yet. Therefore, we used three different doses of Vit C in our study as high (100 mg/kg/day), medium (50 mg/kg/day) and low (15 mg/kg/day) doses intraperitoneally in the present study, and the medium dose was found to be the most effective in the recovery from the diabetes-induced structural damages on rat testicular tissue. Vit C may have a therapeutic effect to be used as a complementary therapy in the treatment of diabetes.


Assuntos
Antioxidantes , Diabetes Mellitus Experimental , Ratos , Animais , Antioxidantes/química , Ácido Ascórbico/farmacologia , Estreptozocina/farmacologia , Estreptozocina/uso terapêutico , Estresse Oxidativo , Vitaminas , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo
12.
In Vivo ; 37(4): 1672-1679, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37369466

RESUMO

BACKGROUND/AIM: Obesity is associated with the structural and functional disorders related to the molecules of the tissues, cells, and membranes. This study aimed to examine the alterations in the secretion of inflammatory cytokines and metabolic factors and structural changes in inguinal (IF) and gonadal (GF) adipose tissues at the molecular level. MATERIALS AND METHODS: The IF and GF tissues of Berlin Fat Mouse Inbred (BFMI) lines namely BFMI852, BFMI856, BFMI860, BFMI861 obese and DBAJ control mouse lines were used for mRNA expression and Attenuated Total Reflection - Fourier Transform Infrared Spectroscopy (ATR-FTIR) studies. The mRNA levels of inflammatory cytokines including leptin, interleukin 6 (IL-6), tumor necrosis factor-alpha (Tnf-α), and insulin-like growth factor-1 (Igf-1), and peroxisome proliferator-activated receptor gamma 2 (Pparγ-2), were investigated using quantitative reverse transcriptase real-time PCR (qRT-PCR). Infrared spectroscopy does not provide information about specific proteins, instead, it gives information about overall (total) proteins, which is called global information. Therefore, in the current study, adequate information about secondary structures of adipose tissues proteins was obtained using artificial neural network (ANN) and secondary derivative-vector normalization methods based on the spectral profiles. RESULTS: According to the mRNA expression studies, high leptin resistance was found in all BFMI lines. Differences were observed in the levels of measured factors except for Igf-1 among BFMI lines. Protein secondary structure studies showed an increase in random coil contents, especially for BFMI860, which indicates denaturation of the proteins. CONCLUSION: Among the spontaneous obese BFMI mouse lines, the BFMI860 line is the most suitable for obesity studies. Obesity-induced effect on the adipose tissues varies considerably with location, type of adipose tissue, and animal line.


Assuntos
Fator de Crescimento Insulin-Like I , Leptina , Camundongos , Animais , Leptina/genética , Fator de Crescimento Insulin-Like I/genética , Camundongos Obesos , Tecido Adiposo/metabolismo , Obesidade/complicações , Citocinas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
13.
Arch Biochem Biophys ; 520(2): 67-73, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22402174

RESUMO

Amifostine is the only approved radioprotective agent by FDA for reducing the damaging effects of radiation on healthy tissues. In this study, the protective effect of amifostine against the damaging effects of ionizing radiation on the white matter (WM) and grey matter (GM) regions of the rat brain were investigated at molecular level. Sprague-Dawley rats, which were administered amifostine or not, were whole-body irradiated at a single dose of 800 cGy, decapitated after 24 h and the brain tissues of these rats were analyzed using Fourier transform infrared microspectroscopy (FTIRM). The results revealed that the total lipid content and CH(2) groups of lipids decreased significantly and the carbonyl esters, olefinic=CH and CH(3) groups of lipids increased significantly in the WM and GM after exposure to ionizing radiation, which could be interpreted as a result of lipid peroxidation. These changes were more prominent in the WM of the brain. The administration of amifostine before ionizing radiation inhibited the radiation-induced lipid peroxidation in the brain. In addition, this study indicated that FTIRM provides a novel approach for monitoring ionizing radiation induced-lipid peroxidation and obtaining different molecular ratio images can be used as biomarkers to detect lipid peroxidation in biological systems.


Assuntos
Amifostina/administração & dosagem , Lesões Encefálicas/metabolismo , Lesões Encefálicas/prevenção & controle , Metabolismo dos Lipídeos/efeitos dos fármacos , Lesões por Radiação/metabolismo , Lesões por Radiação/prevenção & controle , Protetores contra Radiação/administração & dosagem , Animais , Lesões Encefálicas/etiologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Lesões por Radiação/etiologia , Ratos , Ratos Sprague-Dawley , Espectroscopia de Infravermelho com Transformada de Fourier , Distribuição Tecidual , Irradiação Corporal Total/efeitos adversos
14.
Ecotoxicology ; 21(2): 601-14, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22102012

RESUMO

Global warming is already causing salinization of freshwater ecosystems located in semi-arid regions, including Turkey. Daphnids, which are important grazers on phytoplankton and a major food source for fish and invertebrates, are sensitive to not only changes in salinity levels, but also presence of predators. In this study, the interactive effect of salinity toxicity (abiotic factor) with predation pressure mimicked by the fish-exuded kairomone (biotic factor) and the effect of salt acclimation on daphnids were investigated. Impacts of these stressors on daphnid survival, life history and molecular profile were observed. The presence of the kairomone antagonistically alters the effect of salinity, as observed from the 24- and 48-h LC(50) values and survival results. Molecular findings provided solid evidence to this antagonism at even lower salt concentrations, for which antagonism was not evident with organismal data. Fish predation counterbalances the negative effect of salinity in terms of reserve energy density. Therefore, it is important to investigate multiple stressor effects in ecotoxicological bioassays complemented with molecular techniques. The single effect of increasing salinity resulted in increased mortality, decreased fecundity, and slower somatic growth in Daphnia, despite their acclimation to salinity. This insignificance of acclimation indicates that Daphnia do not have any physiological mechanisms to buffer the adverse effects of salinity, making it a very crucial factor. Salinity-induced reduction in population growth rate of freshwater keystone species Daphnia-despite acclimation-indicates that global warming-induced salinity may cascade through the food web and lead to dramatic environmental consequences in the structure of lake ecosystems.


Assuntos
Daphnia/efeitos dos fármacos , Feromônios/farmacologia , Salinidade , Cloreto de Sódio/toxicidade , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/fisiologia , Animais , Cyprinidae/metabolismo , Daphnia/fisiologia , Ecossistema , Aquecimento Global , Dose Letal Mediana , Longevidade/efeitos dos fármacos , Feromônios/metabolismo , Estresse Fisiológico , Testes de Toxicidade Aguda
15.
J Biophotonics ; 15(7): e202100377, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35333440

RESUMO

The structural effects of vitamin A-deficiency were examined on the molecular profiles of biomolecules of male rat hippocampus during prolonged ethanol intake/withdrawal using FT-IR spectroscopy coupled with chemometrics. Liquid ethanol diet with/without vitamin A was maintained to adult rats for 3-months. The rats were decapitated at different ethanol withdrawal times and FT-IR spectra were obtained. Ethanol consumption/withdrawal produced significant changes in proteins' conformations, while having insignificant structural effects on lipids. In vitamin A deficiency, ethanol produced structural changes in lipids by lipid ordering especially in the early-ethanol withdrawal. Furthermore, an increase in lipid and protein content, saturated/unsaturated lipid ratio, a decrease in nucleic acids content and decrease in membrane fluidity were observed. These changes were less severe in the presence of Vitamin A. This study is clinically important for individuals with vitamin A deficiency because they have to be more cautious when consuming alcohol to protect themselves from cognitive dysfunctions.


Assuntos
Alcoolismo , Síndrome de Abstinência a Substâncias , Deficiência de Vitamina A , Alcoolismo/metabolismo , Animais , Quimiometria , Etanol/efeitos adversos , Lipídeos , Masculino , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier , Síndrome de Abstinência a Substâncias/metabolismo , Vitamina A
16.
Biochim Biophys Acta Mol Basis Dis ; 1868(10): 166473, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35753541

RESUMO

Malignant pleural mesothelioma (MPM), an aggressive cancer associated with exposure to fibrous minerals, can only be diagnosed in the advanced stage because its early symptoms are also connected with other respiratory diseases. Hence, understanding the molecular mechanism and the discrimination of MPM from other lung diseases at an early stage is important to apply effective treatment strategies and for the increase in survival rate. This study aims to develop a new approach for characterization and diagnosis of MPM among lung diseases from serum by Fourier transform infrared spectroscopy (FTIR) coupled with multivariate analysis. The detailed spectral characterization studies indicated the changes in lipid biosynthesis and nucleic acids levels in the malignant serum samples. Furthermore, the results showed that healthy, benign exudative effusion, lung cancer, and MPM groups were successfully separated from each other by applying principal component analysis (PCA), support vector machine (SVM), and especially linear discriminant analysis (LDA) to infrared spectra.


Assuntos
Neoplasias Pulmonares , Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurais , Biomarcadores Tumorais , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Mesotelioma/diagnóstico , Mesotelioma/patologia , Neoplasias Pleurais/diagnóstico , Neoplasias Pleurais/patologia , Soro
17.
Anal Chem ; 83(7): 2438-44, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21410135

RESUMO

In this study, the protective effect of amifostine, which is the only FDA-approved radioprotective agent, was investigated against the deleterious effects of ionizing radiation on rat liver microsomal membranes at molecular level. Sprague-Dawley rats, which were either administered amifostine or not, were whole-body irradiated with a single dose of 800 cGy and decapitated after 24 h. The microsomal membranes isolated from the livers of these rats were investigated using FT-IR spectroscopy. The results revealed that radiation caused a significant decrease in the lipid-to-protein ratio and the degradation of lipids into smaller fragments that contain less CH(2) and more carbonyl esters, olefinic═CH and CH(3) groups, which could be interpreted as a result of lipid peroxidation. Radiation altered the secondary structure of proteins by inducing a decrease in the ß-sheet structures and an increase in the turns and random coil structures. Moreover, a dramatic increase in lipid order and a significant decrease in the membrane dynamics were observed in the irradiated group. The administration of amifostine before ionizing radiation inhibited all the radiation induced compositional, structural, and functional damages. In addition, these results suggest that FT-IR spectroscopy provides a novel approach to monitoring radiation-induced damage on biological membranes.


Assuntos
Amifostina/farmacologia , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/efeitos da radiação , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/efeitos da radiação , Protetores contra Radiação/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Animais , Avaliação Pré-Clínica de Medicamentos , Membranas Intracelulares/química , Membranas Intracelulares/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos da radiação , Masculino , Microssomos Hepáticos/química , Microssomos Hepáticos/metabolismo , Redes Neurais de Computação , Ratos , Ratos Sprague-Dawley
18.
Alcohol Clin Exp Res ; 35(11): 2050-62, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21631543

RESUMO

BACKGROUND: The numerous adverse effects of ethanol abuse and ethanol withdrawal on biological systems are well documented. Conversely, the understanding of the molecular mechanisms underlying these pathological effects is still incomplete. This study was undertaken to investigate the effects of short-term chronic ethanol administration and ethanol withdrawal on the molecular structure and function of hippocampal tissue, a brain region important for mnemonic processes and known to be highly susceptible to ethanol intoxication. METHODS: Ethanol was administered to adult Wistar rats by intragastric intubation for 15 days with a stepwise increase in the daily dose from 6 to 12 g/kg body weight, with the highest dose delivered for the last 2 days only. The total daily dose of ethanol was divided into 3 equal portions administered 4 hours apart. Animals were sacrificed by decapitation at 4, 24, and 72 hours after the last ethanol administration to examine potential effects of ethanol intoxication and ethanol withdrawal. Ethanol-related molecular changes were monitored by Fourier transform infrared (FT-IR) spectroscopy. RESULTS: Significant changes in the hippocampal content, structure, and function of lipids, proteins, and nucleic acids were recorded under ethanol intoxication. Seventy-two hours after the cessation of ethanol administration, during the late phase of withdrawal, alterations in the macromolecules' content and conformational changes in protein and nucleic acid structure ameliorated, while the changes in macromolecular ratios, lipid order, and dynamics aggravated. CONCLUSIONS: Our results suggest that 15 days of binge-like drinking resulting in the high blood alcohol concentration (varying in the dose-dependent manner between 253 and 606 mg/dl) produced a strong physical dependence manifested mainly by the changes in lipid profiles pointing toward withdrawal-induced oxidative stress. These results show that ethanol withdrawal may cause equal to or even more severe brain damage than the ethanol itself, which should be considered when designing antialcohol therapies.


Assuntos
Alcoolismo/metabolismo , Hipocampo/metabolismo , Metabolismo dos Lipídeos/fisiologia , Ácidos Nucleicos/metabolismo , Proteínas/metabolismo , Síndrome de Abstinência a Substâncias/metabolismo , Alcoolismo/fisiopatologia , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Modelos Animais de Doenças , Etanol/sangue , Etanol/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiopatologia , Masculino , Ácidos Nucleicos/química , Estrutura Secundária de Proteína , Proteínas/química , Ratos , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Síndrome de Abstinência a Substâncias/fisiopatologia
19.
Cell Biochem Biophys ; 79(2): 271-287, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33442824

RESUMO

The vitamin E derivative with side chain modification (TC6OAc) has been shown to possess anticancer activity in our earlier in vivo studies. It was hypothesized that, as Vitamin E (VE) and VE derivative are fat soluble lipophilic molecules, they exert their function by modulating the lipid metabolism and related pathways. This study aimed to evaluate the cellular impact of this VE derivative (2,5,7,8-Tetramethyl-2-(4'-Methyl-3'-Pentenyl)-6-Acetoxy Chromane-TC6OH), using α-tocopherol as a reference compound throughout the experiments. Their effects on the cellular metabolism, the biophysical properties of cellular lipids and the functional characteristics of cells were monitored in human estrogen receptor (ER) positive breast cancer cells. It has been documented that TC6OH treatment induces tumor cell apoptosis by dissipating the mitochondrial membrane potential, modulating the lipid, transportation and degradation as well as downregulating certain anti-apoptotic and growth factor related proteins. Due to resistance of ER positive cells to the established therapies, the findings of this study are of translational value.


Assuntos
Apoptose/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Vitamina E/farmacologia , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Células MCF-7 , Fluidez de Membrana/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Vitamina E/análogos & derivados , alfa-Tocoferol/farmacologia
20.
Turk J Biol ; 45(4): 549-558, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803453

RESUMO

From the beginning of the COVID-19 coronavirus pandemic in December of 2019, the disease has infected millions of people worldwide and caused hundreds of thousands of deaths. Since then, several vaccines have been developed. One of those vaccines is inactivated CoronaVac-Sinovac COVID-19 vaccine. In this proof of concept study, we first aimed to determine CoronaVac-induced biomolecular changes in healthy human serum using infrared spectroscopy. Our second aim was to see whether the vaccinated group can be separated or not from the non-vaccinated group by applying chemometric techniques to spectral data. The results revealed that the vaccine administration induced significant changes in some functional groups belonging to lipids, proteins and nucleic acids. In addition, the non-vaccinated and vaccinated groups were successfully separated from each other by principal component analysis (PCA) and linear discriminant analysis (LDA). This proof-of-concept study will encourage future studies on CoronaVac as well as other vaccines and will lead to make a comparison between different vaccines to establish a better understanding of the vaccination outcomes on serum biomolecules.

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