Top PDF Amyloid β levels in human red blood cells.

Amyloid β levels in human red blood cells.

Amyloid β levels in human red blood cells.

In addition, inverse relationships between RBC Ab and astax- anthin levels were found (Fig. 2). Our previous in vitro and in vivo murine studies also indicated that carotenoid supplementation, especially astaxanthin, could attenuate Ab-induced oxidative stress in RBCs [9]. It is therefore likely that carotenoids (astaxanthin) act as antioxidants and/or reduce the binding of Ab to RBCs, thereby improving the resistance of RBCs to Ab-induced oxidative damage. For other carotenoid, b-carotene reportedly inhibited fibrillation and oligomerization of Ab [34,35], indicating a possibility that carotenoid moieties may bind to C-terminal portion of Ab, thereby inhibiting the binding of Ab to RBC. On the other hand, for currently unknown reasons, astaxanthin changed the levels of Ab in RBC but not in plasma. This may be related to Ab clearance from plasma, since excessive plasma Ab is reportedly cleared from the circulation by mainly hepatic Ab uptake through the interactions with liver low-density lipoprotein receptor-related protein (LRP-1) [36–38]. Further studies are needed to evaluate the effectiveness and mechanisms by which carotenoid (astaxanthin) could be beneficial for the treatment of dementia.
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High-density lipoprotein prevents SAA-induced production of TNF- α in THP-1 monocytic cells and peripheral blood mononuclear cells

High-density lipoprotein prevents SAA-induced production of TNF- α in THP-1 monocytic cells and peripheral blood mononuclear cells

In this study, we evaluated whether human serum and lipoproteins, especially high-density lipoprotein (HDL), af- fected serum amyloid A (SAA)-induced cytokine release. We verified the effects of SAA on THP-1 cells in serum-free medium compared to medium containing human serum or lipoprotein-deficient serum. SAA-induced tumour necrosis factor-alpha (TNF-α) production was higher in the medium containing lipoprotein-deficient serum than in the medium containing normal human serum. The addition of HDL inhibited the SAA-induced TNF-α release in a dose-dependent manner. This inhibitory effect was specific for HDL and was not affected by low-density lipoprotein or very low-density lipoprotein. In human peripheral blood mononuclear cells, the inhibitory effect of HDL on TNF-α production induced by SAA was less pronounced. However, this effect was significant when HDL was added to lipoprotein-deficient me- dium. In addition, a similar inhibitory effect was observed for interleukin-1 beta release. These findings confirm the important role of HDL and support our previous hypothesis that HDL inhibits the effects of SAA during SAA transport in the bloodstream. Moreover, the HDL-induced reduction in the proinflammatory activity of SAA emphasizes the in- volvement of SAA in diseases, such as atherosclerosis, that are characterized by low levels of HDL.
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Gadd153 and NF-κB crosstalk regulates 27-hydroxycholesterol-induced increase in BACE1 and β-amyloid production in human neuroblastoma SH-SY5Y cells.

Gadd153 and NF-κB crosstalk regulates 27-hydroxycholesterol-induced increase in BACE1 and β-amyloid production in human neuroblastoma SH-SY5Y cells.

same study also demonstrated that BACE1 elevation in the neurons that surround the amyloid plaques is an early event preceding the subsequent neuronal loss that eventually occurs, thereby dispelling the speculation that the elevation in BACE1 levels and activity is an epiphenomenon that merely accompanies neuronal loss. Moreover, neuritic plaques containing a dense core of Ab42 are able to elevate BACE1 expression levels in dystrophic neurites, but not diffuse plaques in transgenic mouse models [47]; [48]. The BACE1 transcription is modulated by a plethora of transcription factors and multitude of transcription factor binding sites have been found in the BACE1 promoter region including those for NF-kB, YY1, Sp1, and PPARc among others [49]. In this study we determined the role of NF-kB in the 27-OHC- induced increase in BACE1 expression. To this end, we used sc514 to inhibit the activation of NF-kB in SH-SY5Y cells concomitantly treated with 27-OHC. We found that the NF-kB inhibitor significantly reduces the 27-OHC-induced increase in BACE1 expression levels. 27-OHC failed to evoke a similar magnitude of increase in BACE1 expression levels in cells concomitantly treated with sc514 compared to cells treated with 27-OHC alone. 27-OHC also induced the nuclear translocation of the p65 and the p50 NF-kB subunits. To further implicate the increased nuclear translocation of the p65 and the p50 NF-kB subunits with the increased expression of BACE1, we performed a ChIP assay to determine the binding of NF-kB to the BACE1 promoter region. Multiple studies have reported the modulation of Figure 7. Schematic representation of the molecular mechanisms involved in the 27-OHC-induced increase in BACE1 expression. 27-OHC activates gadd153 (1) which evokes the phosphorylation of the IKK-complex (2). Phosphorylation IKK complex (3) results in the phosphorylation and subsequent proteasomal degradation of IkB (4), thereby releasing the p65-p50 NF-kB dimer from inhibitory sequestration in the cytosol and allowing the p65-p50 NF-kB dimer to translocate to the nucleus (5). The translocated p65-p50 NF-kB dimer binds to distinct kB sites in the BACE1 promoter region and upregulates BACE1 expression (5). Increased gadd153 expression by 27-OHC may also induce NF-kB activation, nuclear translocation, and subsequently increase BACE1 expression by other mechanism that are yet to be elucidated (6). siRNA to gadd153 reduces the 27-OHC-induced nuclear translocation of NF-kB and thereby attenuates the increase in BACE1(7). The NF-kB inhibitor sc514 also decreases the 27- OHC-induced increase in BACE1 expression by inhibiting the nuclear translocation of NF-kB and subsequent increase in NF-kB-mediated transcription of BACE1 (8).
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Acetylsalicylic Acid and Morphology of Red Blood Cells

Acetylsalicylic Acid and Morphology of Red Blood Cells

Acetylsalicylic acid at normal dose (10mg/kg/day) can cause peroxidation in human erythrocytes, increasing glutathione peroxidase and catalase activities but without changing the susceptibility to oxidation (Durak et al., 2001). Other authors reported decrease in glutathione levels in Wistar rats after acetylsalicylic acid treatment at 10mg/kg with plasma levels about 10 µ g/mL (Guerrero et al., 2004). In fact, it was hypothesized that gastric damage induced by acetylsalicylic acid could be connected with the degradation of the lipid components of the cellular membranes (Javor et al., 1986). Salicylates may cause direct cellular toxicity via inhibition of membrane transport properties (Scheiman and Elta, 1990). Other data have demonstrated that acetylsalicylic acid can alter the inward calcium currents by voltage-gated Ca +2 channels (Greffrath et al., 2002; Kim et al.,
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Age-dependent neuroplasticity mechanisms in Alzheimer Tg2576 mice following modulation of brain amyloid-β levels.

Age-dependent neuroplasticity mechanisms in Alzheimer Tg2576 mice following modulation of brain amyloid-β levels.

Neurogenesis plays an important role in structural neuronal plasticity and network maintenance in the adult brain. It is a complex developmental process characterized by five stages, in which neural stem/progenitor cells in the subgranular layer of the DG develop through proliferation, differentiation, migration, axonal and dendritic targeting, and finally functional synaptic integration into neuronal circuits [36], [23]. Previous studies in nonhuman primates and rodents have shown that immature neurons in the adult DG have high synaptic plasticity, and that this declines with age [58]. Critical for learning and memory, the hippocampus is one of the earliest regions to be affected in AD [59] and dysfunctional neurogenesis consequent to subtle early disease manifestations in the brain could in turn render neurons more vulnerable to AD and contribute to memory impairment [58], whereas enhanced neurogenesis could provide a compensa- tory, endogenous repair mechanism. Prior investigations into hippocampal neurogenesis in mouse models of AD have provided conflicting findings. The majority of these studies report compro- mised neurogenesis [60], [61], [62], but others have described increased neurogenesis [63], [64]. These contradictory findings may stem from the different transgenic models studied, the age of the mice, or the detection methods used to label proliferating cells. In our study, (+)-phenserine treatment of young adult Tg2576 mice resulted in significantly increased numbers of BrdU +
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Isotopic Discrimination in the Double-Crested Cormorant (Phalacrocorax auritus).

Isotopic Discrimination in the Double-Crested Cormorant (Phalacrocorax auritus).

The diet-tissue discrimination factor is the amount by which a consumer’s tissue varies isotopi- cally from its diet, and is therefore a key element in models that use stable isotopes to estimate diet composition. In this study we measured discrimination factors in blood (whole blood, red blood cells and plasma), liver, muscle and feathers of Double-crested Cormorants (Phalacro- corax auritus) for stable isotope ratios of carbon, nitrogen and sulfur. Cormorants exhibited discrimination factors that differed significantly among tissue types (for carbon and nitrogen), and differed substantially (in the context of the isotopic variation among relevant prey species) from those observed in congeneric species. The Double-crested Cormorant has undergone rapid population expansion throughout much of its historic range over the past three decades, leading to both real and perceived conflicts with fisheries throughout North America, and this study provides an essential link for the use of stable isotope analysis in researching foraging ecology, diet, and resource use of this widespread and controversial species.
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Effect of a Peel Passion Fruit Flour (Passiflora edulis f. flavicarpa) Extract on the Labeling of Blood Constituents with Technetium-99m and on the Morphology of Red Blood Cells

Effect of a Peel Passion Fruit Flour (Passiflora edulis f. flavicarpa) Extract on the Labeling of Blood Constituents with Technetium-99m and on the Morphology of Red Blood Cells

Passiflora edulis f. flavicarpa (maracuja) is a fruit consumed in Brazil and worldwide. Blood constituents labeled with technetium-99m (99mTc) are used in nuclear medicine. The effect of P. flavicarpa extract on the radiolabeling of blood constituents and on red blood cells morphology was evaluated. Blood samples from Wistar rats was incubated with P. flavicarpa extract. After that, the labeling of blood constituents with 99mTc was carried out. Samples of plasma and blood cells were precipitated with trichloroacetic acid to isolate the soluble and insoluble fractions of plasma and blood cells. The radioactivity in each fractions was counted and the percentage of radioactivity was determined. Blood smears were also prepared to morphological evaluation and perimeter/area ratio determination. P. flavicarpa extract altered (p<0.05) the fixation of 99m Tc on plasma proteins and the perimeter/area ratio of red blood cells. Substances present in P. flavicarpa extract could affect the labeling of blood constituents with 99m Tc acting in specific targets as membrane of red blood cells.
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Arq Bras Endocrinol Metab  vol.52 número2

Arq Bras Endocrinol Metab vol.52 número2

Type 1 diabetes mellitus is the result of the autoimmune response against pancreatic β-cell(s). At the time of clinical diagnosis near 70% of β-cell mass is been destroyed as a consequence of the auto-destruction that begins months or even years before the clinical diagnosis. Although marked reduction of chronic complications was seen after development and progression of insulin therapy over the years for type 1 diabetic population, associated risks of chro- nic end-organ damage and hypoglycemia still remain. Besides tight glucose control, β-cell mass preservation and/or increase are known to be other im- portant targets in management of type 1 diabetes as long as it reduces chro- nic microvascular complications in the eyes, kidneys and nerves. Moreover, the larger the β-cell mass, the lower the incidence of hypoglycemic events. In this article, we discuss some insights about β-cell regeneration, the importan- ce of regulation of the autoimmune process and what is being employed in human type 1 diabetes in regard to stem cell repertoire to promote regenera- tion and/or preservation of β-cell mass. (Arq Bras Endocrinol Metab 2008; 52/2:407-415)
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Changes in red blood cells membrane protein composition during hemodialysis procedure

Changes in red blood cells membrane protein composition during hemodialysis procedure

After dialysis, HD patients showed a statistical signifi- cant increase in RBC count and Hb concentration; no statistical significant changes were found in the other hemato- logical parameters (see Table 1). Concerning the RBC mem- brane protein profile, a statistically significant decrease in spectrin, an increase in band 3, and an altered spectrin/band 3 ratio were found after HD procedure. We also observed after HD some trends toward the control profile (band 6 and band 7) and some trends in opposition to control profile (a further decrease in ankyrin, protein 4.1, protein 4.2, and band 5). We must notice that band 3 increased and reached a statistically significantly higher value than that presented by the control. Most of the ratios, reflecting protein interactions, presented values that were still different from those of the control.
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Red blood cells radial dispersion in blood flowing through microchannels: The role of temperature

Red blood cells radial dispersion in blood flowing through microchannels: The role of temperature

Human blood is a complex physiological fluid that consists of deformable blood cells suspended in plasma containing mostly water. It is well known that red blood cells (RBCs) are the most abundant type of cells in whole blood, with a concentration around 45% in human adults. Due the high RBC concentration, it is believed that rheological properties of whole blood are mainly determined by the presence of the RBCs within the flow. Hence, blood flow behavior in microcirculation has long been a hot topic of interest by the biome- dical research community with an extensive history of experimental investigations (Chien et al., 1984; Goldsmith and Turitto, 1986; Lima et al., 2012; Garcia et al., 2012; Wong et al., 2012; Pinho et al., 2013b; Yaginuma et al., 2013; Faustino et al., 2014; Rodrigues et al., 2015).
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The aquaporin-3-inhibiting potential of polyoxotungstates

The aquaporin-3-inhibiting potential of polyoxotungstates

their mechanisms of action in each type of cancer cell are still far from being understood [3]. The antitumor activity of these inorganic compounds seems to be caused, at least in part, by the inhibition of certain enzymes such as alkaline phosphatases, kinases, ecto-nucleotidases, glucosidases, and P-type ATPases [5–8]. Moreover, some POMs are also understood to interfere with mitochondria function and DNA, while others can exert an immunomodulatory activity [9,10]. As the incidence of cancer is increasing every year all over the world, along with the growing resistance effect and high toxicity of chemotherapeutic agents, some researchers chose POMs as alternative anti-tumor substances with promising results in suppressing tumor growth [3,9,11–13].
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Dithiothreitol revisited in red cells : a new head for an old hat

Dithiothreitol revisited in red cells : a new head for an old hat

Abstract. In the present article the authors make an approach over the applications of dithiothreitol (DTT) in its different clinical- laboratory, potential and up-to-date sources. Dithiothreitol is a chemical reagent with a wide actuation spectrum not only from a laboratorial view but also from a therapeutic standpoint, more clinical and practical. DTT (i) is frequently used in a variety of experiences that involve proteins or peptides, protecting sulfhydryl groups from oxidation and reducing disulfide bonds between cysteines; (ii) is also used in the study of disulfide exchange reactions of protein disulfides; (iii) is able to keep glutathione in the reduced state; (iv) acts as an “antidote” enabling the activity of detoxification systems; (v) participates in cellular mechanisms such as vesiculation, cell morphology, signal transduction pathways (hormone-‘like’ role), etc.; (vi) can be used in the treatment approach of diseases like cystinosis or medical conditions resulting from ion or metal toxicity. In erythrocytes, there’s literature pointing that DTT may trigger changes on the normal discoid shape following metabolic depletion, and additionally modulate the exovesiculation kinetics as demonstrated by us. The present article dissects in detail recent findings in our Unit concerning the DTT influence on human erythrocytes.
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Apoptosis of non-parasitised red blood cells in Plasmodium yoelii malaria

Apoptosis of non-parasitised red blood cells in Plasmodium yoelii malaria

Augmented levels of erythrocytic apoptosis have been reported in different anaemia-associated clinical disorders, suggesting that apoptosis is involved in this haematological complication (Lang & Qadri 2012). In malaria, the relationship between erythrocytic apopto- sis and anaemia has not yet been explored. We there- fore investigated whether nRBC apoptosis detected in experimental malaria could be associated with the num- ber of peripheral RBCs, parasitaemia or plasmatic levels of NO, cytokines and anti-RBC antibodies. Our present data confirm our previous results concerning increased levels of apoptotic nRBCs during the late stage of P. yoe- lii 17XL infection in BALB/c mice and also suggest that the degree of anaemia is not related to the extent of apop- tosis. We also observed that nRBC apoptosis was associ- ated with parasite load, but not with the components of the immune response that were assessed herein.
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Red blood cells transfusions in oncological patients treated with radio- and chemoterapy

Red blood cells transfusions in oncological patients treated with radio- and chemoterapy

Pretransfuzijska ispitivanja, prema standardnim opera- tivnim procedurama (SOP), obuhvatala su slede će elemente: odre đivanje krvne grupe ABO i Rh(D) bolesnika, skrining klini čki značajnih iregularnih eritrocitnih antitela u serumu bolesnika, direktni antihumani globulin (AHG) test za boles- nika, provera i potvrda krvne grupe ABO Rh(D) davaoca, iz- vo đenje imunoserološke interreakcije između seruma boles- nika i eritrocita davaoca. Krvne grupe bolesnika ra đene su koriš ćenjem ABO i Rh(D) reagenasa Seraclone anti-A, anti- B i anti-D(RH1)232 (Biotest, Nema čka) metodom u epruve- ti; skrining iregularnih eritrocitnih antitela koriš ćenjem skri- ning eritrocita DiaMed, ID-DiaCell I, II metodom na gelu (DiaMed, Švajcarska); AHG testovi koriš ćenjem AHG rea- gensa Seraclone Anti Human-Globulin monoklonal anti-IgG, anti-C3c, anti-C3d (Biotest, Nema čka); identifikacija antitela vršena je koriš ćenjem panela eritrocita DiaMed na gelu, ID- DiaPanel (DiaMed, Švajcarska); interreakcije su ra đene me- todom na gelu koriš ćenjem Liss/Coombs (anti-IgG + C3d) ID kartica (DiaMed, Švajcarska).
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Clinics  vol.66 número9

Clinics vol.66 número9

In conclusion, our results suggest that the consumption of organic red grape juice, which is a source of polyphenols, may benefit the antioxidant capacity, glucose homeostasis and microcirculatory parameters in endurance athletes. Although limited by the small sample size, our results are consistent with other studies and may suggest that the consumption of grape juice can positively affect an athlete’s health and reduce the risk of cardiovascular diseases. Further studies are required to clarify the role of poly- phenols in glucose homeostasis and the antioxidant capacity based on the microvascular parameters in athletes using different modalities. Clinical trials using OGJ may be used to investigate the possible benefits of OGJ on athletic performance and health.
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Rev. bras. farmacogn.  vol.12 suppl.1

Rev. bras. farmacogn. vol.12 suppl.1

The analysis of the results (Table 1) indicates that there is a significant decrease (p<0.05) on the uptake of Tc-99m by the red blood cells with the concentrations from 0.4 up to 20 mg/ml of the extract of Ginkgo biloba. The analysis of the results also indicates that there is a significant decrease (p<0.05) in the fixation of Tc-99m in insoluble fractions of the blood cells when the concentrations from 0.4 up to 40 mg/ml of the extract.

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Basophilic stippling and reactive lymphocytosis in bovine anaplasmosis – A case report

Basophilic stippling and reactive lymphocytosis in bovine anaplasmosis – A case report

___________________________________________________________________________ Abstract: Anaplasmosis is known for causing anemia in cattle. However, morphological changes in the red and white blood cells are not often described in bovine anaplasmosis cases. Thus, the aim of this work was to describe changes in blood cell morphology, such as the incidence of basophilic stippling in red blood cells and the reactive lymphocytosis, presented by a 10-month-old Jersey heifer, who was bred in a dairy farm in Juiz de Fora County (MG), Forest Zone of Minas Gerais State (Zona da Mata Mineira). The animal presented clinical signs of hyperthermia and hypocorous mucosae, which suggested hemoparasitosis. Laboratory examination demonstrated the presence of Anaplasma marginale in several erythrocytes, 13.4% of parasitemia, red blood cells presenting basophilic stippling, severe macrocytic normochromic anemia, increased total number of leukocytes resulting from the increased number of lymphocytes, some large lymphocytes with basophilic cytoplasm, and other lymphocytes showed granules in the cytoplasm. These findings are not often described in bovine anaplasmosis cases. So, this work shows the relevance of blood smear examinations to diagnose the hemoparasite, as well as to identify cellular morphological changes caused by it.
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Evaluation of zebu nellore cattle blood samples using the Cell-Dyn 3500 hematology analyzer

Evaluation of zebu nellore cattle blood samples using the Cell-Dyn 3500 hematology analyzer

complete blood count of Zebu Nellore heifers from Cell- dyn 3500, with those obtained from a semi-automated cell counter (Celm CC 510) and the manual technique. Blood samples were collected from the jugular vein in 5 mL EDTA vacuum tubes from 58 Nellore heifers, at 24 months of age. Samples were processed in parallel in the three different techniques. Results were analyzed using paired t test, Pearson’s correlation and the Bland-Altmann method. There was a strong correlation for all parameters analyzed by Cell-Dyn 3500, manual method and semi- automated cell counter, except for basophils and monocytes counts. These results confirm that this analyzer is reliable for blood samples analysis of zebu cattle.
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Spatial distributions of red blood cells significantly alter local haemodynamics.

Spatial distributions of red blood cells significantly alter local haemodynamics.

The haematocrit distribution technique employed in the present study is founded on the assumption that the time-average pixel intensity at a given location is related to the haematocrit in a predictable way. The calibration stage (Figure S1) showed that there is a certain amount of scatter about the best fit line, with an uncertainty of ,0.014. However, the normalisation of the images largely removed the random differences. This correction should not significantly affect the shape of the haematocrit profiles. The use of empirical equations (S3 and S4) to convert the feed haematocrit to a channel haematocrit is a further assumption, which is likely to influence the absolute values of haematocrit reported here. Ideally, the output from each channel would have been collected and the haematocrit measured directly. However, in the presence of RBC aggregation, the required experimental protocol precluded such an approach. The flow rates used in the present study range from 0.15–1.28 m l/min, which over a time period of 20 s equates to volume of 0.05–0.43 m l split between the four outflow branches. Separating the sample for each branch under the current conditions was thus not feasible for the present study. Furthermore, these very low flow rates, combined with the short time scales required due to aggregation precluded measuring the flow rate, which would have been good way to validate the estimated velocities and evaluate the efficacy of the adjustment based on the data of Poelma et al. [43].
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Rev. Soc. Bras. Med. Trop.  vol.22 número4

Rev. Soc. Bras. Med. Trop. vol.22 número4

W hen the hemolytic power of whole venom on human red blood cells was studied, the following results were obtained: a high percentage of low hemolysis (89% ), a medium percentage of hemolysis (15 to 30%) in a small number of venoms, though the results were statistically very clear, and also a high percentage of hemolysis (35-100% ) in a small number of venoms (8%). These results show that the number of animals whose venoms had a hemolytic effect was small, though the effect was quite evident This may also have occurred because of the concentration of hemoly­ tic power in each venom (Table 4 and Figure 1).
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