scholarly journals Circulating oxidized LDL, increased in patients with acute myocardial infarction, is accompanied by heavily modified HDL

2020 ◽  
Vol 61 (6) ◽  
pp. 816-829 ◽  
Author(s):  
Naoko Sawada ◽  
Takashi Obama ◽  
Shinji Koba ◽  
Takashi Takaki ◽  
Sanju Iwamoto ◽  
...  
Keyword(s):  
Healthy Subjects ◽  
Oxidized Ldl ◽  
Structural Features ◽  
Anion Exchange Column ◽  
Transmission Electron ◽  
Lysine Residues ◽  
Acute Mi ◽  
Flow Through ◽  
Oxidized Pc

Oxidized LDL (oxLDL) is a known risk factor for atherogenesis. This study aimed to reveal structural features of oxLDL present in human circulation related to atherosclerosis. When LDL was fractionated on an anion-exchange column, in vivo-oxLDL, detected by the anti-oxidized PC (oxPC) mAb, was recovered in flow-through and electronegative LDL [LDL(−)] fractions. The amount of the electronegative in vivo-oxLDL, namely oxLDL in the LDL(−) fraction, present in patients with acute MI was 3-fold higher than that observed in healthy subjects. Surprisingly, the LDL(−) fraction contained apoA1 in addition to apoB, and HDL-sized particles were observed with transmission electron microscopy. In LDL(−) fractions, acrolein adducts were identified at all lysine residues in apoA1, with only a small number of acrolein-modified residues identified in apoB. The amount of oxPC adducts of apoB was higher in the LDL(−) than in the L1 fraction, as determined using Western blotting. The electronegative in vivo-oxLDL was immunologically purified from the LDL(−) fraction with an anti-oxPC mAb. The majority of PC species were not oxidized, whereas oxPC and lysoPC did not accumulate. Here, we propose that there are two types of in vivo-oxLDL in human circulating plasma and the electronegative in vivo-oxLDL accompanies oxidized HDL.

scholarly journals Interactions between Babesia microti merozoites and rat kidney cells in a short-term in vitro culture and animal model

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marta Albertyńska ◽  
Hubert Okła ◽  
Krzysztof Jasik ◽  
Danuta Urbańska-Jasik ◽  
Przemysław Pol
Keyword(s):  
Epithelial Cells ◽  
Cross Sections ◽  
Rat Kidney ◽  
Babesia Microti ◽  
Renal Tubules ◽  
Renal Epithelial Cells ◽  
Transmission Electron ◽  
Flow Through

AbstractBabesiosis is one of the most common infections in free-living animals and is rapidly becoming significant among human zoonoses. Cases of acute renal failure in humans caused by Babesia spp. have been described in the literature. The kidneys are characterised by intense blood flow through the blood vessels, which increases the likelihood of contact with the intra-erythrocyte parasite. The aim of this study was to observe the influence of B. microti (ATCC 30221) on renal epithelial cells in vitro cultured (NRK-52E line) and Wistar rats’ kidney. Both NRK-52E cells and rats’ kidney sections were analysed by light microscopy, transmission electron microscopy (TEM) and fluorescence in situ hybridization (FISH). Necrotic changes in renal epithelial cells have been observed in vitro and in vivo. In many cross-sections through the rats’ kidney, adhesion of blood cells to the vascular endothelium, accumulation of erythrocytes and emboli were demonstrated. In NRK-52E culture, elements with a distinctly doubled cell membrane resembling B. microti were found inside the cytoplasm and adjacent to the cell layer. The study indicates a chemotactic tendency for B. microti to adhere to the renal tubules' epithelium, a possibility of piroplasms entering the renal epithelial cells, their proliferation within the cytoplasm and emboli formation.

scholarly journals Quantification of malondialdehyde and 4-hydroxynonenal adducts to lysine residues in native and oxidized human low-density lipoprotein

1997 ◽  
Vol 322 (1) ◽  
pp. 317-325 ◽  
Author(s):  
Jesús R. REQUENA ◽  
Min Xin FU ◽  
Mahtab U. AHMED ◽  
Alicia J. JENKINS ◽  
Timothy J. LYONS ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Gas Chromatography ◽  
Oxidized Ldl ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Thiobarbituric Acid ◽  
Low Density ◽  
Lysine Residues

Malondialdehyde (MDA) and 4-hydroxynonenal (HNE) are major end-products of oxidation of polyunsaturated fatty acids, and are frequently measured as indicators of lipid peroxidation and oxidative stress in vivo. MDA forms Schiff-base adducts with lysine residues and cross-links proteins in vitro; HNE also reacts with lysines, primarily via a Michael addition reaction. We have developed methods using NaBH4 reduction to stabilize these adducts to conditions used for acid hydrolysis of protein, and have prepared reduced forms of lysine-MDA [3-(Nε-lysino)propan-1-ol (LM)], the lysine-MDA-lysine iminopropene cross-link [1,3-di(Nε-lysino)propane (LML)] and lysine-HNE [3-(Nε-lysino)-4-hydroxynonan-1-ol (LHNE)]. Gas chromatography/MS assays have been developed for quantification of the reduced compounds in protein. RNase incubated with MDA or HNE was used as a model for quantification of the adducts by gas chromatography/MS. There was excellent agreement between measurement of MDA bound to RNase as LM and LML, and as thiobarbituric acid-MDA adducts measured by HPLC; these adducts accounted for 70Ő80% of total lysine loss during the reaction with MDA. LM and LML (0.002Ő0.12mmol/mol of lysine) were also found in freshly isolated low-density lipoprotein (LDL) from healthy subjects. LHNE was measured in RNase treated with HNE, but was not detectable in native LDL. LM, LML and LHNE increased in concert with the formation of conjugated dienes during the copper-catalysed oxidation of LDL, but accounted for modification of < 1% of lysine residues in oxidized LDL. These results are the first report of direct chemical measurement of MDA and HNE adducts to lysine residues in LDL. LM, LML and LHNE should be useful as biomarkers of lipid peroxidative modification of protein and of oxidative stress in vitro and in vivo.

scholarly journals Optimization of Hyaluronate-Based Liposomes to Augment the Oral Delivery and the Bioavailability of Berberine

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5759
Author(s):  
Hussam I. Kutbi ◽  
Hani Z. Asfour ◽  
Ahmed K. Kammoun ◽  
Alaa Sirwi ◽  
Simona Cavalu ◽  
...  
Keyword(s):  
Oral Delivery ◽  
Water Solubility ◽  
Physical Stability ◽  
Entrapment Efficiency ◽  
Structural Features ◽  
Transmission Electron ◽  
Mean Size ◽  
Therapeutic Activities

Various perspectives had been utilized to enhance the poor intestinal permeability and bioavailability of drugs with low water solubility. Berberine (Brb) is a unique molecule that possesses multiple therapeutic activities such as antimicrobial, anti-inflammatory, antioxidant and anti-hyperglycemic effects. To improve Brb permeability and bioavailability, this study presents a newly developed formulation, namely Brb hyaluronate-based liposomes, prepared by using film hydration method and characterized by dynamic light scattering measurements, entrapment efficiency percentage (EE%), transmission electron microscope (TEM), in vitro drug release and physical stability. The bioavailability of the selected formulations was assessed in vivo after oral administration to rats. The results revealed an enhanced effect of hyaluronic acid on the entrapment efficiency, reaching 78.1 ± 0.1% with mean size 520.7 ± 19.9 nm. Sustained release of Brb was recorded up to 24 h in comparison to Brb solution. Physical stability was maintained for three months at refrigeration temperature. Results of pharmacokinetics studies indicated the potential of the liposomal formulation to increase the oral bioavailability of Brb and to accelerate its entry into the bloodstream. The obtained results are accredited to the lipophilic nature of the prepared system, resembling the structural features of bio-membrane, in addition to their small size that enhances intestinal penetration.

scholarly journals Structural Connectivity-Based Parcellation of the Dopaminergic Midbrain in Healthy Subjects and Schizophrenic Patients

Medicina ◽  
2020 ◽  
Vol 56 (12) ◽  
pp. 686
Author(s):  
Gianpaolo Antonio Basile ◽  
Alessia Bramanti ◽  
Salvatore Bertino ◽  
Giuseppina Cutroneo ◽  
Antonio Bruno ◽  
...  
Keyword(s):  
Healthy Subjects ◽  
Structural Connectivity ◽  
Structural Features ◽  
Detailed Characterization ◽  
Diffusion Tractography ◽  
Core Feature ◽  
Schizophrenic Patients ◽  
Anatomical Research

Background and objectives: Functional deregulation of dopaminergic midbrain regions is a core feature of schizophrenia pathophysiology. Anatomical research on primates suggests that these regions may be subdivided into distinct, topographically organized functional territories according to their connectivity to the striatum. The aim of the present work was the reconstruction of dopaminergic midbrain subregions in healthy subjects and schizophrenic patients and the evaluation of their structural connectivity profiles. Materials and Methods: A hypothesis-driven connectivity-based parcellation derived from diffusion tractography was applied on 24 healthy subjects and 30 schizophrenic patients to identify distinct territories within the human dopaminergic midbrain in vivo and non-invasively. Results: We identified a tripartite subdivision of dopaminergic midbrain, including limbic, prefrontal and sensorimotor territories. No significant differences in structural features or connectivity were found between subjects and patients. Conclusions: The parcellation scheme proposed herein may help to achieve detailed characterization of structural and functional anomalies of the dopaminergic midbrain in schizophrenic patients.

scholarly journals Green Synthesis of Silver Nanoparticles: Structural Features andIn VivoandIn VitroTherapeutic Effects againstHelicobacter pyloriInduced Gastritis

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Muhammad Amin ◽  
Sadaf Hameed ◽  
Asghar Ali ◽  
Farooq Anwar ◽  
Shaukat Ali Shahid ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Silver Nanoparticles ◽  
Cost Effective ◽  
Structural Features ◽  
X Ray Diffraction ◽  
Ag Nps ◽  
Transmission Electron ◽  
H Pylori

This study evaluatesin vivoandin vitroanti-Helicobacter pylori (H. pylori)efficacy of silver nanoparticles (Ag-NPs) prepared via a cost-effective green chemistry route whereinPeganum harmalaL. seeds extract was used as a reducing and capping agent. The structural features, as elucidated by surface plasmon resonance spectrophotometry, transmission electron microscopy, and powder X-ray diffraction spectroscopy, revealed the Ag-NPs synthesized to be polydispersed in nature and spherical in shape with 5–40 nm size. A typical Ag-NPs suspension (S5), with size being 15 nm, when testedin vitroagainst forty-two local isolates and two reference strains, showed a considerable anti-H. pyloriactivity. In case ofin vivotrial againstH. pyloriinduced gastritis, after oral administration of 16 mg/kg body weight of S5for seven days, a complete clearance was recorded in male albino rates. In comparative time-killing kinetics, S5exhibited dose- and time-dependent anti-H. pyloriactivity that was almost similar to tetracycline and clarithromycin, less than amoxicillin, but higher than metronidazole. Furthermore, S5was found to be an equally effective anti-H. pyloriagent at low (≤4) and high pH with no drug resistance observed even up to 10 repeated exposures while a significant drug resistance was recorded for most of the standard drugs employed. The present results revealed the potential of the synthesized Ag-NPs as safer bactericidal agents for the treatment ofH. pyloriinduced gastritis.

Role of Methylglyoxal in Diabetic Cardiovascular and Kidney Diseases: Insights from Basic Science for Application into Clinical Practice

2018 ◽  
Vol 24 (26) ◽  
pp. 3072-3083 ◽  
Author(s):  
Sowndramalingam Sankaralingam ◽  
Angham Ibrahim ◽  
MD Mizanur Rahman ◽  
Ali H. Eid ◽  
Shankar Munusamy
Keyword(s):  
Therapeutic Strategy ◽  
Kidney Diseases ◽  
Vascular Dysfunction ◽  
Dicarbonyl Compound ◽  
Renal Complications ◽  
Lysine Residues ◽  
Patients With Diabetes ◽  
Prevalence Of Diabetes Mellitus

Background: The incidence and prevalence of diabetes mellitus are increasing globally at alarming rates. Cardiovascular and renal complications are the major cause of morbidity and mortality in patients with diabetes. Methylglyoxal (MG) - a highly reactive dicarbonyl compound – is increased in patients with diabetes and has been implicated to play a detrimental role in the etiology of cardiovascular and renal complications. Derived from glucose, MG binds to arginine and lysine residues in proteins, and the resultant end products serve as surrogate markers of MG generation in vivo. Under normal conditions, MG is detoxified by the enzyme glyoxalase 1 (Glo1), using reduced glutathione as a co-factor. Elevated levels of MG is known to cause endothelial and vascular dysfunction, oxidative stress and atherosclerosis; all of which are risk factors for cardiovascular diseases. Moreover, MG has also been shown to cause pathologic structural alterations and impair kidney function. Conversely, MG scavengers (such as N-acetylcysteine, aminoguanidine or metformin) or Nrf2/Glo1 activators (such as trans-resveratrol / hesperetin) are shown to be useful in preventing MG-induced cardiovascular and renal complications in diabetes. However, clinical evidence supporting the MG lowering properties of these agents are limited and hence, need further investigation. Conclusion: Reducing MG levels directly using scavengers or indirectly via activation of Nrf2/Glo1 may serve as a novel and potent therapeutic strategy to counter the deleterious effects of MG in diabetic complications.

Pharmacokinetic Evaluation of 99mTc-radiolabeled Solid Lipid Nanoparticles and Chitosan Coated Solid Lipid Nanoparticles

2020 ◽  
Vol 20 (13) ◽  
pp. 1044-1052
Author(s):  
Nasrin Abbasi Gharibkandi ◽  
Sajjad Molavipordanjani ◽  
Jafar Akbari ◽  
Seyed Jalal Hosseinimehr
Keyword(s):  
Solid Lipid Nanoparticles ◽  
Lipid Nanoparticles ◽  
High Resistivity ◽  
Scanning Calorimetry ◽  
Liver Uptake ◽  
Solid Lipid ◽  
Transmission Electron ◽  
Main Portion ◽  
Pharmacokinetic Behavior

Background: Solid Lipid Nanoparticles (SLNs) possess unique in vivo features such as high resistivity, bioavailability, and habitation at the target site. Coating nanoparticles with polymers such as chitosan greatly affects their pharmacokinetic behavior, stability, tissue uptake, and controlled drug delivery. The aim of this study was to prepare and evaluate the biodistribution of 99mTc-labeled SLNs and chitosan modified SLNs in mice. Methods: 99mTc-oxine was prepared and utilized to radiolabel pre-papered SLNs or chitosan coated SLNs. After purification of radiolabeled SLNs (99mTc-SLNs) and radiolabeled chitosan-coated SLNs (99mTc-Chi-SLNs) using Amicon filter, they were injected into BALB/c mice to evaluate their biodistribution patterns. In addition, nanoparticles were characterized using Transmission Electron Microscopy (TEM), Fourier-transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), X-ray Powder Diffraction (XRD) and Dynamic Light Scattering (DLS). Results: 99mTc-oxine with high radiochemical purity (RCP~100%) and stability (RCP > 97% at 24 h) was used to provide 99mTc-SLNs and 99mTc-Chi-SLNs with high initial RCP (100%). TEM image and DLS data suggest 99mTc- SLNs susceptibility to aggregation. To that end, the main portion of 99mTc-SLNs radioactivity accumulates in the liver and intestines, while 99mTc-Chi-SLNs sequesters in the liver, intestines and kidneys. The blood radioactivity of 99mTc-Chi-SLNs was higher than that of 99mTc-SLNs by 7.5, 3.17 and 3.5 folds at 1, 4 and 8 h post-injection. 99mTc- Chi-SLNs uptake in the kidneys in comparison with 99mTc-SLNs was higher by 37.48, 5.84 and 11 folds at 1, 4 and 8h. Conclusion: The chitosan layer on the surface of 99mTc-Chi-SLNs reduces lipophilicity in comparison with 99mTc- SLNs. Therefore, 99mTc-Chi-SLNs are less susceptible to aggregation, which leads to their lower liver uptake and higher kidney uptake and blood concentration.

Traceable Peptidic Ligands that Target Ghrelin Receptors

2020 ◽  
Vol 21 (10) ◽  
pp. 955-964 ◽  
Author(s):  
Mengjie Liu ◽  
John Wade ◽  
Mohammed Akhter Hossain
Keyword(s):  
In Vivo Imaging ◽  
Peptide Hormone ◽  
Structural Features ◽  
Pharmacological Properties ◽  
Imaging Studies ◽  
Cognate Receptor ◽  
Ghrelin Receptors ◽  
Biochemical Research

: Ghrelin is a 28-amino acid octanoylated peptide hormone that is implicated in many physiological and pathophysiological processes. Specific visualization of ghrelin and its cognate receptor using traceable ligands is crucial in elucidating the localization, functions, and expression pattern of the peptide’s signaling pathway. Here 12 representative radio- and fluorescently-labeled peptide-based ligands are reviewed for in vitro and in vivo imaging studies. In particular, the focus is on their structural features, pharmacological properties, and applications in further biochemical research.

Polyamines and Related Nitrogen Compounds in the Chemotherapy of Neglected Diseases Caused by Kinetoplastids

2018 ◽  
Vol 18 (5) ◽  
pp. 321-368 ◽  
Author(s):  
Juan A. Bisceglia ◽  
Maria C. Mollo ◽  
Nadia Gruber ◽  
Liliana R. Orelli
Keyword(s):  
Drug Targets ◽  
Redox Homeostasis ◽  
Cost Effective ◽  
Structural Features ◽  
Mammalian Host ◽  
Neglected Diseases ◽  
Nitrogen Compounds ◽  
Chemical Structures

Neglected diseases due to the parasitic protozoa Leishmania and Trypanosoma (kinetoplastids) affect millions of people worldwide, and the lack of suitable treatments has promoted an ongoing drug discovery effort to identify novel nontoxic and cost-effective chemotherapies. Polyamines are ubiquitous small organic molecules that play key roles in kinetoplastid parasites metabolism, redox homeostasis and in the normal progression of cell cycles, which differ from those found in the mammalian host. These features make polyamines attractive in terms of antiparasitic drug development. The present work provides a comprehensive insight on the use of polyamine derivatives and related nitrogen compounds in the chemotherapy of kinetoplastid diseases. The amount of literature on this subject is considerable, and a classification considering drug targets and chemical structures were made. Polyamines, aminoalcohols and basic heterocycles designed to target the relevant parasitic enzyme trypanothione reductase are discussed in the first section, followed by compounds directed to less common targets, like parasite SOD and the aminopurine P2 transporter. Finally, the third section comprises nitrogen compounds structurally derived from antimalaric agents. References on the chemical synthesis of the selected compounds are reported together with their in vivo and/or in vitro IC50 values, and structureactivity relationships within each group are analyzed. Some favourable structural features were identified from the SAR analyses comprising protonable sites, hydrophobic groups and optimum distances between them. The importance of certain pharmacophoric groups or amino acid residues in the bioactivity of polyamine derived compounds is also discussed.

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