scholarly journals A previously unknown way of heme detoxification in the digestive tract of cats

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alexandr B. Duzhak ◽  
Petr S. Sherin ◽  
Vadim V. Yanshole ◽  
Sergey L. Veber ◽  
Sergey I. Baiborodin ◽  
...  
Keyword(s):  
Digestive Tract ◽  
Living Organism ◽  
Important Process ◽  
Domestic Cats ◽  
Hydroxyapatite Nanoparticles ◽  
Free Heme ◽  
Bone Content ◽  
Neutral Conditions ◽  
Toxic Molecule

AbstractFree heme is a highly toxic molecule for a living organism and its detoxification is a very important process, especially for carnivorous animals. Here we report the discovery of a previously unknown process for neutralizing free heme in the digestive tract of domestic cats. The cornerstone of this process is the encapsulation of heme into carbonated hydroxyapatite nanoparticles, followed by their excretion with faeces. This way of heme neutralization resembles the formation of insoluble heme-containing particles in the digestive tracts of other hematophagous species (for example, the formation of insoluble hemozoin crystals in malaria-causing Plasmodium parasites). Our findings suggest that the encapsulation of heme molecules into a hydroxyapatite matrix occurs during the transition from the acidic gastric juice to the small intestine with neutral conditions. The formation of these particles and their efficiency to include heme depends on the bone content in a cat’s diet. In vitro experiments with heme-hydroxyapatite nanoparticles confirm the proposed scenario.

Influence of pH on Complexing of Model β-d-Glucans with Zearalenone

2004 ◽  
Vol 67 (12) ◽  
pp. 2741-2746 ◽  
Author(s):  
A. YIANNIKOURIS ◽  
J. FRANÇOIS ◽  
L. POUGHON ◽  
C.-G. DUSSAP ◽  
G. JEMINET ◽  
...  
Keyword(s):  
Digestive Tract ◽  
Three Dimensional ◽  
Cooperative Interaction ◽  
Random Coil ◽  
Adsorption Mechanisms ◽  
Constant Quantity ◽  
Alkaline Conditions ◽  
Neutral Conditions ◽  
Influence Of Ph

Previous studies have shown that isolated β-(1,3 and 1,6)-d-glucans and related alkali-extracted fractions from the cell wall of Saccharomyces cerevisiae are able to complex with zearalenone in vitro (affinity up to 50%) and thus may reduce the bioavailability of toxins in the digestive tract. The complexation mechanisms involve cooperative interaction between the two chemical entities that can be computed by Hill's model. Various linear or branched soluble or insoluble β-d-glucans were evaluated to elucidate their roles in the adsorption mechanisms under three pH conditions (3.0, 6.0, and 8.0) found in the digestive tract. A constant quantity of each β-d-glucans (1 mg/ml) was mixed at 39°C with increasing amounts of zearalenone (2 to 100 μg/ml), and the amount of bound toxin was measured. Acidic and neutral conditions gave the highest affinity rates (64 to 77%) by β-(1,3)-d-glucans, whereas alkaline conditions decreased adsorption except when β-(1,6)-d-glucan side chains were branched on β-(1,3)-d-glucans. Alkaline conditions appear to impede the active three dimensional conformation of β-d-glucans and favor single helix and/or random coil structures. Study of the equilibrium between β-d-glucan–bound and free toxins revealed that two types of chemical interactions occur during toxin complexation with β-d-glucans, identified as weak chemical linkages such as hydrogen and van der Waals bonds.

scholarly journals Proteome Profiling of PMJ2-R and Primary Peritoneal Macrophages

2021 ◽  
Vol 22 (12) ◽  
pp. 6323
Author(s):  
Alexander L. Rusanov ◽  
Peter M. Kozhin ◽  
Olga V. Tikhonova ◽  
Victor G. Zgoda ◽  
Dmitry S. Loginov ◽  
...  
Keyword(s):  
Proteomic Analysis ◽  
Living Organism ◽  
Peritoneal Macrophages ◽  
In Vitro Models ◽  
Individual Characteristics ◽  
Essential Proteins ◽  
Comparative Proteomic Analysis ◽  
Immortalized Cell ◽  
The Individual

In vitro models are often used for studying macrophage functions, including the process of phagocytosis. The application of primary macrophages has limitations associated with the individual characteristics of animals, which can lead to insufficient standardization and higher variability of the obtained results. Immortalized cell lines do not have these disadvantages, but their responses to various signals can differ from those of the living organism. In the present study, a comparative proteomic analysis of immortalized PMJ2-R cell line and primary peritoneal macrophages isolated from C57BL/6 mice was performed. A total of 4005 proteins were identified, of which 797 were quantified. Obtained results indicate significant differences in the abundances of many proteins, including essential proteins associated with the process of phagocytosis, such as Elmo1, Gsn, Hspa8, Itgb1, Ncf2, Rac2, Rack1, Sirpa, Sod1, C3, and Msr1. These findings indicate that outcomes of studies utilizing PMJ2-R cells as a model of peritoneal macrophages should be carefully validated. All MS data are deposited in ProteomeXchange with the identifier PXD022133.

Kisspeptin/Kiss1r system and angiogenic and immunological mediators at the maternal-fetal interface of domestic cats

2021 ◽  
Author(s):  
Luciano Cardoso Santos ◽  
Jeane Martinha dos Anjos Cordeiro ◽  
Larissa da Silva Santana ◽  
Bianca Reis Santos ◽  
Erikles Macêdo Barbosa ◽  
...  
Keyword(s):  
Gene Expression ◽  
Late Pregnancy ◽  
Domestic Cats ◽  
Placental Angiogenesis ◽  
Spatiotemporal Expression ◽  
Gene Correlation ◽  
Lh Release ◽  
Gonadotrophin Releasing Hormone ◽  
Maternal Fetal Interface

Abstract The Kisspeptin/Kiss1r system is a key regulator of reproduction by stimulating gonadotrophin-releasing hormone (GnRH) and luteinizing hormone (LH) release, and in vitro studies have shown that Kisspeptin can modulate angiogenesis and immune function, factors that are also essential for reproduction However, there are no studies on the expression of Kisspeptin/Kiss1r at the maternal-fetal interface in domestic cats and its relationship with angiogenic and immunological mediators. Thus, our objective was to evaluate the spatiotemporal expression profile of Kisspeptin/Kiss1r and angiogenic and immunological mediators in the uterus and placenta of domestic cats during pregnancy. Uterus and placenta samples were collected from cats in mid pregnancy (N = 6) and late pregnancy (N = 6), in addition to uterus from non-pregnant cats in diestrus (N = 7), to evaluate protein and gene expression of Kiss1, Kiss1r, VEGF, Flk-1, PLGF, INFγ, MIF, TNFα, IL6, and IL10 by immunohistochemistry and qPCR. Pregnancy increased the uterine expression of Kiss1 and Kiss1r, especially at the late pregnancy, in addition to upregulating INFy, MIF, Vegf, Il10, and Tnf and downregulating Plgf. Higher placental expression of Kiss1r and Plgf mRNA occurred at the late pregnancy, while the expression of Kiss1, VEGF, Flk-1, INFy, TNFα, Il6, and IL10 was higher in the mid of pregnancy. A positive correlation between Kiss1 and Tnf was observed in the placenta, while Kiss1r had a negative correlation with Infγ, Il6, and Il10. The findings reveal that Kisspeptin/Kiss1r and angiogenic and immunological mediators at the maternal-fetal interface of pregnant cat have a gene correlation and are modulated by the gestational age. These data suggest possible functional links of Kisspeptin in placental angiogenesis and immunology.

Effect of hydroxyapatite nanoparticles on K562 cells in vitro

2008 ◽  
Vol 23 (2) ◽  
pp. 222-224 ◽  
Author(s):  
Pei Chen ◽  
Honglian Dai ◽  
Yingchao Han ◽  
Meizhen Yin ◽  
Shipu Li
Keyword(s):  
K562 Cells ◽  
Hydroxyapatite Nanoparticles

Antitumoural hydroxyapatite nanoparticles-mediated hepatoma-targeted trans-arterial embolization gene therapy: in vitro and in vivo studies

2012 ◽  
Vol 32 (6) ◽  
pp. 998-1007 ◽  
Author(s):  
Gaopeng Li ◽  
Lu Ye ◽  
Jingsheng Pan ◽  
Miaoyun Long ◽  
Zizhuo Zhao ◽  
...  
Keyword(s):  
Gene Therapy ◽  
Arterial Embolization ◽  
In Vivo Studies ◽  
Hydroxyapatite Nanoparticles

scholarly journals Nutrient sensing; transcriptomic response and regulation of gut motility in an agastric vertebrate

2019 ◽  
Author(s):  
Hoang T. M. D. Le ◽  
Kai K. Lie ◽  
Angela Etayo ◽  
Ivar Rønnestad ◽  
Øystein Sæle
Keyword(s):  
Digestive Tract ◽  
Genetic Regulation ◽  
Nutrient Sensing ◽  
Transcriptomic Response ◽  
Gut Motility ◽  
Gut Evacuation ◽  
Vitro Model ◽  
Transcriptomic Changes ◽  
Upregulated Genes

AbstractThe transcriptome of nutrient sensing and the regulation of gut motility by nutrients in a stomachless fish with a short digestive tract; the ballan wrasse (Labrus berggylta) were investigated. Using an in vitro model, we differentiate how signals initiated by physical stretch and nutrients modulate the gut evacuation rate and motility patterns, and transcriptomic changes. Stretch on the intestine by inert cellulose initiated fast evacuation out of the anterior intestine compared to the digestible protein and lipid. Stretch on the intestine upregulated genes associated with increased muscle activity, whereas nutrients stimulated pathways related to ribosomal activity and the increase in the expression of several neuropeptides which are directly involved in gut motility regulation. Our findings show that physical pressure in the intestine initiate contractions propelling the matter towards the exit, whereas the sensing of nutrients modulates the motility to prolong the residence of digesta in the digestive tract for optimal digestion.Summary statementPressure by food speed up peristalsis in the intestine, but the intestines ability to sense nutrients slow down peristalsis for better digestion. This is partly controlled by genetic regulation.

scholarly journals Effects of some organic acids and salts on microbial fermentation in the digestive tract of piglets estimated using an in vitro gas production technique

2008 ◽  
Vol 14 (4) ◽  
pp. 311 ◽  
Author(s):  
K. PARTANEN ◽  
T. JALAVA
Keyword(s):  
Organic Acids ◽  
Formic Acid ◽  
Digestive Tract ◽  
Sodium Benzoate ◽  
Gas Production ◽  
Control Treatment ◽  
Potassium Sorbate ◽  
Microbial Fermentation ◽  
Calcium Formate

An in vitro gas production technique was used to screen different organic acids (formic, propionic, lactic, citric, and fumaric acid), organic salts (calcium formate, potassium sorbate, and sodium benzoate), and inorganic phosphoric acid for their ability to modulate microbial fermentation in the digestive tract of piglets. For the incubation, 40 ml of culture medium (53% buffer, 45% frozen ileal digesta, and 2% fresh faeces) was dispensed in vessels containing 5 ml of buffer, 0.5 g of feed, and 20 ìl of liquid or 20 mg of solid acidifiers. Gas production was measured every 15 min during the 24 h incubation at 39°C, and a Gompertz bacterial growth model was applied to the gas production data. Formic acid was the only acid that reduced the maximum rate of gas production (ìm) compared to that in the control treatment (P < 0.05). The ìm was slower in vessels with formic acid than in those with calcium formate, citric acid, and potassium sorbate (P < 0.05) Calcium formate increased the ìm compared to the control treatment (P < 0.05). The maximum volume of gas produced and the lag time did not differ between different acidifiers (P > 0.05). When investigating formic-acid-based mixtures that contained 1–5% of potassium sorbate and/or sodium benzoate, the estimated parameters for the Gompertz growth model did not differ from those for treatments with plain formic acid (P > 0.05). However, concentrations of total volatile fatty acids, acetic acid, propionic acid, and n-butyric acid were reduced by all the mixtures (P < 0.05), but not by plain formic acid (P > 0.05). In conclusion, organic acids and salts were found to differ in their ability to modulate microbial fermentation in the digestive tract of piglets. Mixing formic acid with potassium sorbate or sodium benzoate changed fermentation patterns, and the possibility to use them to enhance the antimicrobial effect of formic acid should be investigated further in vivo.;

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