Food supplement “carrageenan” and its effect on the organism

Author(s):  
O.E. Luneva ◽  

Food additives are positioned as harmless, although, their components affectthe physiological processes associated with the permeability of the wall of the gastrointestinal tract (GIT) and intestinal microbiota. This article describes thecarrageenan supplement and its effects on the body in in vitro and in vivo experiments. The experimental part is devoted to analysis of the intestinalmicrobiota of laboratory rats with the consumption of the carrageenan dietary supplement in the amount of about 4,4 % of the standard feed.

Open Biology ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 200172
Author(s):  
Ya Zhang ◽  
Luis Alfonso Yañez Guerra ◽  
Michaela Egertová ◽  
Cleidiane G. Zampronio ◽  
Alexandra M. Jones ◽  
...  

Somatostatin (SS) and allatostatin-C (ASTC) are structurally and evolutionarily related neuropeptides that act as inhibitory regulators of physiological processes in mammals and insects, respectively. Here, we report the first molecular and functional characterization of SS/ASTC-type signalling in a deuterostome invertebrate—the starfish Asterias rubens (phylum Echinodermata). Two SS/ASTC-type precursors were identified in A. rubens (ArSSP1 and ArSSP2) and the structures of neuropeptides derived from these proteins (ArSS1 and ArSS2) were analysed using mass spectrometry. Pharmacological characterization of three cloned A. rubens SS/ASTC-type receptors (ArSSR1–3) revealed that ArSS2, but not ArSS1, acts as a ligand for all three receptors. Analysis of ArSS2 expression in A. rubens using mRNA in situ hybridization and immunohistochemistry revealed stained cells/fibres in the central nervous system, the digestive system (e.g. cardiac stomach) and the body wall and its appendages (e.g. tube feet). Furthermore, in vitro pharmacological tests revealed that ArSS2 causes dose-dependent relaxation of tube foot and cardiac stomach preparations, while injection of ArSS2 in vivo causes partial eversion of the cardiac stomach. Our findings provide new insights into the molecular evolution of SS/ASTC-type signalling in the animal kingdom and reveal an ancient role of SS-type neuropeptides as inhibitory regulators of muscle contractility.


2012 ◽  
Vol 3 (2) ◽  
pp. 137-144 ◽  
Author(s):  
F. Vieira de Souza ◽  
R. Roque ◽  
J.L. Silva Moreira ◽  
M. Resende de Souza ◽  
J.R. Nicoli ◽  
...  

The aim of this study was to assess the potential horizontal transfer of genetic traits for antibiotic resistance between lactobacilli isolated from the chicken gut, both in vitro and in vivo. Thirty-seven Lactobacillus spp. strains isolated from the gizzard, small and large intestines and caeca of free-range broiler chickens showed multi-drug resistance as assessed by disc diffusion assays. The minimum inhibitory concentration (MIC) for vancomycin, tetracycline, erythromycin and chloramphenicol was determined in De Man, Rogosa and Sharpe broth in a microplate assay. Almost all the lactobacilli isolates were resistant to vancomycin (except strains belonging to the Lactobacillus acidophilus group) and to tetracycline (MIC≥128 μg/ml). Only five strains were resistant to erythromycin, and six to chloramphenicol. The transfer rate in filter mating experiments performed using L. acidophilus strain 4M14E (EmR), Lactobacillus vaginalis strain 5M14E (CmR), Lactobacillus salivarius strain 5C14C (EmR), and the 4G14L and 3C14C strains of Lactobacillus reuteri (CmR) showed a frequency of approximately 1×104 cfu/ml of double-resistant transconjugants for the different combinations. The exception was the L. salivarius 5C14C (EmR) and L. vaginalis 5M14E (CmR) mating combination, which produced no transconjugants. In vivo experiments performed in gnotobiotic mice by mating L. acidophilus 4M14E (EmR) with L. reuteri 3C14C (CmR), L. reuteri 4G14L (CmR) or L. vaginalis 5M14E (CmR) resulted in transconjugants at 3.95±0.29, 3.16±0.33, and 4.55±1.52 log10 cfu/g of faeces, respectively. Taken together, these data suggest that genetic exchange may occur between native bacterial strains within the gastrointestinal tract of chickens, which might maintain a dynamic gene pool conferring antibiotic resistance upon indigenous microbiota components, even in the absence of the pathogens. This possibility must be taken into account as a complementary criterion when lactobacilli are screened for probiotic use.


2020 ◽  
Author(s):  
Anna Wójcik-Gładysz

Discovered in 1999, ghrelin, is one of the peptides co-creating the hypothalamicgastrointestinal axis, otherwise known as the brain-gut axis. Ghrelin participates in many physiological processes and spectrum of its activity is still being discovered. This 28 amino acid peptide ‒ a product of the ghrl gene, was found in all vertebrates and is synthesized and secreted mainly from enteroendocrine X/A cells located in the gastric mucosa of the stomach. Expression of the ghrelin receptor has been found in many nuclei of the hypothalamus involved in appetite regulation. Therefore it’s presumed that ghrelin is one of the crucial hormones deciphering the energy status required for the maintenance of organism homeostasis. Ghrelin acts as a signal of starvation or energy insufficiency and its level in plasma is reduced after the meal. Neuropeptide Y (NPY) and agouti-related peptide (AgRP; NPY/AgRP) neurons located in the arcuate nucleus (ARC) area are the main target of ghrelin in the hypothalamus. This subpopulation of neurons is indispensable for inducing orexigenic action of ghrelin. Moreover ghrelin acting as a neurohormone, mainly in the hypothalamus area, plays an important role in the regulation of growth and reproduction processes. Indeed, ghrelin action on reproductive processes has been observed in the systemic effects exerted at both hypothalamus-pituitary and gonadal levels. Similarly the GH-releasing ghrelin action was observed both on the hypothalamus level and directly on the somatotrophic cells in the pituitary and this dose-related GH releasing activity was found in in vitro as well as in in vivo experiments. In recent years, numerous studies revealed that ghrelin potentially takes part in the treatment of diseases associated with serious disturbances in the organism energy balance and/or functioning of the gastrointestinal tract. It was underlined that ghrelin may be a hormone with a broad spectrum of therapeutic effect on obesity and anorexia nervosa, as well as may also have protective effect on neurodegenerative diseases, inflammatory disorders or functional changes in the body caused by cancers. In overall, ghrelin treatment has been tested in over 100 preclinical studies with healthy volunteers as well as patients with various types of cancer, eating disorders such as anorexia nervosa and bulimia nervosa. It was observed that ghrelin has an excellent clinical safety profile and emerging side effects occurred only in 3–10% of patients and did not constitute a sufficient premise to discontinue the therapy. In general, it can be concluded that ghrelin may be sufficiently used as a prescription drug.


1997 ◽  
Vol 80 (4) ◽  
pp. 920-927 ◽  
Author(s):  
Pierre Hocquellet ◽  
Marie-Dominique L'Hotellier

Abstract Speciation analyses are essential to investigate the effects of dietary components on bioavailability of mineral micronutrients. Enzymolysis was used. An in vitro model simulating enzymatic activity in the gastrointestinal tract of monogastric species was developed and used to assess availability of Fe, Cu, Mn, and Zn in some foodstuffs. The solubility of each element in samples was measured by atomic absorption spectrometry after enzymatic treatment. Data are in good agreement with information obtained from earlier, more expensive nutritional surveys or in vivo experiments and, therefore, allow prediction of the tendency of a particular food to induce mineral deficiency. In addition, ligands responsible for inhibiting intestinal absorption were identified by determining the amount of metal released after treatment of the insoluble residue with an appropriate enzyme such as cellulase and phytase, used respectively to study fiber and phytate interactions. Enzymolysis may be useful for optimizing mineral supplementations though its nutritional significance is somewhat limited by the fact that it does not take into account the dynamic changes in the gastrointestinal tract. Enzymolysis is a prerequisite for further speciation studies of complex systems and in some instances is the only way for specifying physicochemical forms of elements.


Planta Medica ◽  
2017 ◽  
Vol 83 (09) ◽  
pp. 790-796 ◽  
Author(s):  
Emmy Tuenter ◽  
Sebastiaan Bijttebier ◽  
Kenn Foubert ◽  
Annelies Breynaert ◽  
Sandra Apers ◽  
...  

AbstractHymenocardine is a cyclopeptide alkaloid present in the root bark of Hymenocardia acida. In traditional African medicine, the leaves and roots of this plant are used to treat malaria, and moderate in vitro antiplasmodial activity has been reported for hymenocardine. However, in view of its peptide-like nature, potential metabolisation after oral ingestion has to be taken into account when considering in vivo experiments. In this study, the stability and small intestinal absorption of hymenocardine was assessed using an in vitro gastrointestinal dialysis model. In addition, potential liver metabolisation was investigated in vitro by incubation with a human S9 fraction. Moreover, hymenocardine was administered to rats per os, and blood and urine samples were collected until 48 and 24 h after oral administration, respectively. All samples resulting from these three experiments were analyzed by LC-MS. Analysis of the dialysate and retentate, obtained from the gastrointestinal dialysis model, indicated that hymenocardine is absorbed unchanged from the gastrointestinal tract, at least in part. After S9 metabolisation, several metabolites of hymenocardine could be identified, the major ones being formed by the reduction and/or the loss of an N-methyl group. The in vivo study confirmed that hymenocardine is absorbed from the gastrointestinal tract unchanged, since it could be identified in both rat plasma and urine, together with hymenocardinol, its reduction product.


Author(s):  
Sundar Ram Naganathan ◽  
Marko Popovic ◽  
Andrew C Oates

The body axis of vertebrate embryos is periodically segmented into bilaterally symmetric pairs of somites. The anteroposterior (AP) length of somites, their position and left-right symmetry are thought to be molecularly determined prior to somite morphogenesis. Here we discover that in zebrafish embryos, initial somite AP lengths and positions are imprecise and consequently many somite pairs form left-right asymmetrically. Strikingly, these imprecisions are not left unchecked and we find that AP lengths adjust within an hour after somite formation, thereby increasing morphological symmetry. We find that AP length adjustments result entirely from changes in somite shape without change in somite volume, with changes in AP length being compensated by corresponding changes in mediolateral length. The AP adjustment mechanism is facilitated by somite surface tension, which we show by comparing in vivo experiments and in vitro single-somite explant cultures with a mechanical model. Length adjustment is inhibited by perturbation of Integrin and Fibronectin, consistent with their involvement in surface tension. In contrast, the adjustment mechanism is unaffected by perturbations to the segmentation clock, thus revealing a distinct process that determines morphological segment lengths. We propose that tissue surface tension provides a general mechanism to adjust shapes and ensure precision and symmetry of tissues in developing embryos.


2021 ◽  
Vol 93 (5) ◽  
pp. 635-639
Author(s):  
Andrei V. Gordeev ◽  
Elena A. Galushko ◽  
Natalia M. Savushkina

The significant humoral effect of the renin-angiotensin-aldosterone system on the regulation of the cardiovascular system and blood pressure has long been widely known. However, the identification and interpretation of new components of renin-angiotensin-aldosterone system in recent years can significantly expand the range of its potential effects on the body. The anti-inflammatory effect of drugs that block angiotensin II and its receptors, including in rheumatic diseases, can become practically significant for General therapists by their effect on reducing the concentration of inflammatory mediators and angiogenesis processes. The organoprotective and anti-inflammatory potentials of drugs that reduce the production of at demonstrated in vitro and in vivo experiments allow us to consider them as first-line angiotropic agents in patients with rheumatoid arthritis, especially in the presence of pathology of the cardiovascular system and kidneys.


2019 ◽  
Vol 56 (6) ◽  
pp. 753-759
Author(s):  
N. M. Savushkina ◽  
E. A. Galushko ◽  
N. V. Demidova ◽  
A. V. Gordeev

At present, the role of the renin-angiotensin system (RAS) in regulating the cardiovascular system and maintaining water and electrolyte homeostasis has been well studied. However, over the past decades, new components of the RAS have been identified, suggesting a wider range of its potential effects on the body. It is of fundamentally importance for rheumatologists to affect inflammation, including rheumatoid inflammation, through blockade of angiotensin (AT) II formation via the effects of AT 1–7 and angiotensin-converting enzyme inhibitors, as well as through suppression of angiogenesis, primarily by reducing the production of endothelial growth factor. The organ-protective and antiinflammatory potential of drugs that reduce the production of AT, which has been proven in in vitro and in vivo experiments, allows us to consider them as first-line angiotropic agents in patients with rheumatoid arthritis, especially in the presence of concomitant hypertension and/or nephropathy.


Toxins ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 360 ◽  
Author(s):  
Yosuke Uchiyama ◽  
Masahiko Takino ◽  
Michiko Noguchi ◽  
Nozomi Shiratori ◽  
Naoki Kobayashi ◽  
...  

Citreoviridin (CTVD), a mycotoxin called yellow rice toxin, is reported to be related to acute cardiac beriberi; however, its toxicokinetics remain unclear. The present study elucidated the toxicokinetics through in vivo experiments in swine and predicted the human toxicokinetics by comparing the findings to those from in vitro experiments. In vivo experiments revealed the high bioavailability of CTVD (116.4%) in swine. An intestinal permeability study using Caco-2 cells to estimate the toxicokinetics in humans showed that CTVD has a high permeability coefficient. When CTVD was incubated with hepatic S9 fraction from swine and humans, hydroxylation and methylation, desaturation, and dihydroxylation derivatives were produced as the predominant metabolites. The levels of these products produced using human S9 were higher than those obtained swine S9, while CTVD glucuronide was produced slowly in human S9 in comparison to swine S9. Furthermore, the elimination of CTVD by human S9 was significantly more rapid in comparison to that by swine S9. These results suggest that CTVD is easily absorbed in swine and that it remains in the body where it is slowly metabolized. In contrast, the absorption of CTVD in humans would be the same as that in swine, although its elimination would be faster.


2014 ◽  
Vol 7 (1) ◽  
pp. 20-24 ◽  
Author(s):  
Krassimira S. Yakimova ◽  
Rumen P. Nikolov ◽  
Ivan G. Todorov ◽  
Milen H. Hristov

Abstract Leptin inhibits feeding, reduces body weight and increases thermogenesis. Experimental data suggest involvement of GABAergic mechanisms in the regulation of feeding behavior and energy balance. The present study was set to determine the effect of combinations from leptin, GABAB-agonist baclofen and GABAB-antagonist CGP35348 on thermoregulation of male Wistar rats, using in vivo and in vitro experiments. The substances used for in vivo experiments were administered intraperitoneally (i.p.). The measurement of the body temperature was done via thermistor probes (TX8) and monitored on multichannel recorder Iso-Thermex16. In vitro experiments were conducted on rat PO/AH neurons, recorded extracellulary by conventional electrophysiological equipment, using brain slice preparations. The separate intraperitoneal injection of leptin as well as GABAB-antagonist CGP35348 produced significant hyperthermia in rats while the GABAB-agonist baclofen caused a decrease in the core body temperature. The probable synergy between the hyperthermic effects of leptin and GABAB-antagonist did not occur. On the contrary, the effect of this combination was lower as compared to the result of the separate administration of GABAB-antagonist. When leptin was applied just prior to GABAB-agonist baclofen, neither of their separate effects appeared. In vivo effects determined correlated with in vitro changes of firing rate observed in PO/AH neurons. The data from this study provide a new point of view concerning the interactions of leptin and GABA on the level of thermoregulation. These results represent a step forward in understanding the complicated mechanisms involved in thermoregulation.


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