scholarly journals On The Relative Importance of Aerobic Metabolism in Small Nematode Parasites of the Alimentary Tract II. the Utilization of Oxygen at Low Partial Pressures by Small Nematode Parasites of the Alimentary Tract

1949 ◽  
Vol 2 (2) ◽  
pp. 166 ◽  
Author(s):  
WP Rogers
Keyword(s):  
Small Intestine ◽  
Haemonchus Contortus ◽  
Alimentary Tract ◽  
Intestinal Parasites ◽  
Low Oxygen ◽  
Nematode Parasites ◽  
Partial Pressures ◽  
Consumption Rates

Nippostrongylus muris, Haemonchus contortus, Nematodirus spathiger, and N. filicollis are all capable of utilizing oxygen for respiratory purposes even when it is present at very low oxygen tensions. Thus with a partial pressure as low as 5 mm. of mercury the respiration of Nippostrongylus muris may reach 40 per cent. of its maximum rate, whereas Nematodirus spp. and H. contortus may respire at 25 and 12 per cent. of their maximum rates respectively. Further, the results indicate that in vivo the oxygen consumption rates may sometimes reach 80 per cent. of the maximum in vitro rate in the case of Nippostrongylus muris in the small intestine of the rat and 40 per cent. in the case of Nematodirus spp. in the small intestine of the sheep. Haemonchus contortus in the sheep abomasums probably respires at a relatively lower rate than either of the intestinal parasites in vivo.

scholarly journals Characterization of a Rhodanese Homologue from Haemonchus Contortus and its Immune-Modulatory Effects on Goat Immune Cells in Vitro

2020 ◽  
Author(s):  
Yujian Wang ◽  
Muhammad Ehsan ◽  
Jianmei Huang ◽  
Kalibixiati Aimulajiang ◽  
RuoFeng Yan ◽  
...  
Keyword(s):  
Haemonchus Contortus ◽  
Mononuclear Cells ◽  
Small Ruminants ◽  
Parasitic Nematodes ◽  
Dependent Manner ◽  
Peripheral Blood Mononuclear ◽  
Nematode Parasites ◽  
Wide Range

Abstract Background: Suppression and modulation of the immune response of the host by nematode parasites have been reported widely. Rhodaneses or thiosulfate: cyanide sulfurtransferases are present in a wide range of organisms, such as archea, bacteria, fungi, plants and animals. Previously, it was reported that a rhodanese homology could bind by goat peripheral blood mononuclear cells (PBMCs) in vivo.Results: In the present study, we cloned and produced recombinant rhodanese protein originated from Haemonchus contortus (rHCRD), which was one of the parasitic nematodes of small ruminants. The effect of this protein on modulating the immunity of goat PBMC and monocyte was studied in the current work. The predominant localization of the natural HCRD protein was verified as the bowel wall and body surface of worms, according to the immunohistochemical tests. It was proved in this study that the serum produced by artificially infecting goats with H. contortus successfully recognized rHCRD which conjugated goat PBMCs. The rHCRD was co-incubated with goat PBMCs to observe the immunomodulatory effect on proliferation, apoptosis and secretion of cytokines exerted by HCRD. The results showed that the interaction of rHCRD suppressed proliferation of goat PBMCs stimulated by ConA but did not induce the apoptosis of goat PBMCs. After rHCRD exposure, the production of TNF-α and IFN-γ were significantly decreased, however, it significantly increased the secretion of IL-10 and TGF-β1 in goat PBMCs. Phagocytotic assay by FITC-dextran internalization showed that rHCRD inhibited the phagocytosis of goat monocytes. Moreover, rHCRD could down-regulate the expression of MHC-II on goat monocytes in a dose-dependent manner. Conclusions: These discoveries proposed a possible target as immunomodulator, which was potentially beneficial to illuminate the interaction between parasites and hosts in the molecular level and hunt for innovative protein species as candidate targets of drug and vaccine.

scholarly journals Characterization of a rhodanese homologue from Haemonchus contortus and its immune-modulatory effects on goat immune cells in vitro

2020 ◽  
Author(s):  
Yujian Wang ◽  
Muhammad Ehsan ◽  
Jianmei Huang ◽  
Kalibixiati Aimulajiang ◽  
RuoFeng Yan ◽  
...  
Keyword(s):  
Haemonchus Contortus ◽  
Mononuclear Cells ◽  
Small Ruminants ◽  
Dependent Manner ◽  
Peripheral Blood Mononuclear ◽  
Mhc I ◽  
Nematode Parasites ◽  
Wide Range

Abstract Background: Modulation of the host immune response by nematode parasites has been widely reported. Rhodaneses (thiosulfate: cyanide sulfurtransferases) are present in a wide range of organisms, such as archaea, bacteria, fungi, plants and animals. Previously, it was reported that a rhodanese homologue could be bound by goat peripheral blood mononuclear cells (PBMCs) in vivo.Methods: In the present study, we cloned and produced a recombinant rhodanese protein originating from Haemonchus contortus (rHCRD), a parasitic nematode of small ruminants. rHCRD was co-incubated with goat PBMCs to assess its immunomodulatory effects on proliferation, apoptosis and cytokine secretion.Results: We verified that the natural HCRD protein localized predominantly to the bowel wall and body surface of the parasite. We further demonstrated that serum produced by goats artificially infected with H. contortus successfully recognized rHCRD, which bound to goat PBMCs. rHCRD suppressed proliferation of goat PBMCs stimulated by concanavalin A but did not induce apoptosis in goat PBMCs. The production of TNF-α and IFN-γ decreased significantly, whereas secretion of IL-10 and TGF-β1 increased, in goat PBMCs after exposure to rHCRD. rHCRD also inhibited phagocytosis by goat monocytes. Moreover, rHCRD downregulated the expression of major histocompatibility complex (MHC)-II on goat monocytes in a dose-dependent manner, but did not alter MHC-I expression.Conclusions: These results propose a possible immunomodulatory target that may help illuminate the interactions between parasites and their hosts at the molecular level and reveal innovative protein species as candidate drug and vaccine targets.

scholarly journals On the Relative Importance of Aerobic Metabolism in Small Nematode Parasites of the Alimentary Tract I. Oxygen Tensions in the Normal Environment of the Parasites

1949 ◽  
Vol 2 (2) ◽  
pp. 157 ◽  
Author(s):  
WP Rogers
Keyword(s):  
Small Intestine ◽  
Haemonchus Contortus ◽  
Alimentary Canal ◽  
Alimentary Tract ◽  
Aerobic Metabolism ◽  
Relative Importance ◽  
Nematode Parasites ◽  
Normal Environment ◽  
Oxygen Tensions

As a preliminary to the study of the relative importance . of aerobic mechanisms in the metabolism of Nippostrongylus muris, Nematodirus spathiger, Nematodirus filicollis, and Haemonchus contortus at oxygen pressures of the normal environmental fluids of these parasites, the determination of oxygen in the contents of the small intestine of the rat and sheep, and the abomasum of the sheep, has been carried out. The method which was used allowed measurements to be made close to the mucosa of the alimentary canal of anaesthetized animals in which the circulation was left intact, and the procedure ensured that conditions in the normal gut were very little disturbed.

scholarly journals Characterization of a rhodanese homologue from Haemonchus contortus and its immune-modulatory effects on goat immune cells in vitro

2020 ◽  
Author(s):  
Yujian Wang ◽  
Muhammad Ehsan ◽  
Jianmei Huang ◽  
Kalibixiati Aimulajiang ◽  
RuoFeng Yan ◽  
...  
Keyword(s):  
Haemonchus Contortus ◽  
Mononuclear Cells ◽  
Small Ruminants ◽  
Dependent Manner ◽  
Peripheral Blood Mononuclear ◽  
Mhc I ◽  
Nematode Parasites ◽  
Wide Range

Abstract Background: Modulation of the host immune response by nematode parasites has been widely reported. Rhodaneses (thiosulfate: cyanide sulfurtransferases) are present in a wide range of organisms, such as archaea, bacteria, fungi, plants and animals. Previously, it was reported that a rhodanese homologue could be bound by goat peripheral blood mononuclear cells (PBMCs) in vivo.Methods: In the present study, we cloned and produced a recombinant rhodanese protein originating from Haemonchus contortus (rHCRD), a parasitic nematode of small ruminants. rHCRD was co-incubated with goat PBMCs to assess its immunomodulatory effects on proliferation, apoptosis and cytokine secretion.Results: We verified that the natural HCRD protein localized predominantly to the bowel wall and body surface of the parasite. We further demonstrated that serum produced by goats artificially infected with H. contortus successfully recognized rHCRD, which bound to goat PBMCs. rHCRD suppressed proliferation of goat PBMCs stimulated by concanavalin A but did not induce apoptosis in goat PBMCs. The production of TNF-α and IFN-γ decreased significantly, whereas secretion of IL-10 and TGF-β1 increased, in goat PBMCs after exposure to rHCRD. rHCRD also inhibited phagocytosis by goat monocytes. Moreover, rHCRD down-regulated the expression of major histocompatibility complex (MHC)-II on goat monocytes in a dose-dependent manner, but did not alter MHC-I expression. Conclusions: These results propose a possible immunomodulatory target that may help illuminate the interactions between parasites and their hosts at the molecular level and reveal innovative protein species as candidate drug and vaccine targets.

scholarly journals The Biological Significance of Haemoglobin in Nematode Parasites II. The Properties of the Haemoglobins as Studied in Living Pabasites

1949 ◽  
Vol 2 (4) ◽  
pp. 399 ◽  
Author(s):  
WP Rogers
Keyword(s):  
Oxygen Tension ◽  
Haemonchus Contortus ◽  
Biological Significance ◽  
Water Soluble ◽  
Nematode Parasites

In the parasites examined, the amounts of water-soluble haematin compounds, of which haemoglobin formed the large part, varied considerably; Nippo$rongylus murls contained about 6 mg. (as haematin) per g. dry wt. of tissue, Nematodirus spp. and Haemonchus contortus about 0.8 mg. per g. dry wt. Evidence is presented which indicates that the haemoglobin of Nippo$rongylus muris may be oxygenated in vivo, at least sometimes. The haemoglobin in the living parasites was easily oxygenated and deoxygenated; when the oxygen tension in the medium surrounding the parasites in vitro at 37�C. fell below about 13 mm. of mercury (Nippostrongylus muris) or 9 mm. of mercury (Haemonchus contortus and Nematodirus spp.) the oxyhaemoglobin became deoxygenated.

scholarly journals Characterization of a rhodanese homologue from Haemonchus contortus and its immune-modulatory effects on goat immune cells in vitro

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Yujian Wang ◽  
Muhammad Ehsan ◽  
Jianmei Huang ◽  
Kalibixiati Aimulajiang ◽  
RuoFeng Yan ◽  
...  
Keyword(s):  
Haemonchus Contortus ◽  
Mononuclear Cells ◽  
Small Ruminants ◽  
Dependent Manner ◽  
Peripheral Blood Mononuclear ◽  
Mhc I ◽  
Nematode Parasites ◽  
Wide Range

Abstract Background Modulation of the host immune response by nematode parasites has been widely reported. Rhodaneses (thiosulfate: cyanide sulfurtransferases) are present in a wide range of organisms, such as archaea, bacteria, fungi, plants and animals. Previously, it was reported that a rhodanese homologue could be bound by goat peripheral blood mononuclear cells (PBMCs) in vivo. Methods In the present study, we cloned and produced a recombinant rhodanese protein originating from Haemonchus contortus (rHCRD), a parasitic nematode of small ruminants. rHCRD was co-incubated with goat PBMCs to assess its immunomodulatory effects on proliferation, apoptosis and cytokine secretion. Results We verified that the natural HCRD protein localized predominantly to the bowel wall and body surface of the parasite. We further demonstrated that serum produced by goats artificially infected with H. contortus successfully recognized rHCRD, which bound to goat PBMCs. rHCRD suppressed proliferation of goat PBMCs stimulated by concanavalin A but did not induce apoptosis in goat PBMCs. The production of TNF-α and IFN-γ decreased significantly, whereas secretion of IL-10 and TGF-β1 increased, in goat PBMCs after exposure to rHCRD. rHCRD also inhibited phagocytosis by goat monocytes. Moreover, rHCRD downregulated the expression of major histocompatibility complex (MHC)-II on goat monocytes in a dose-dependent manner, but did not alter MHC-I expression. Conclusions These results propose a possible immunomodulatory target that may help illuminate the interactions between parasites and their hosts at the molecular level and reveal innovative protein species as candidate drug and vaccine targets.

Effects of in vitro low oxygen tension preconditioning of buccal fat pad stem cells on in Vivo articular cartilage tissue repair

Life Sciences ◽  
2021 ◽  
pp. 119728
Author(s):  
Fatemeh Dehghani Nazhvani ◽  
Leila Mohammadi Amirabad ◽  
Arezo Azari ◽  
Hamid Namazi ◽  
Simzar Hosseinzadeh ◽  
...  
Keyword(s):  
Stem Cells ◽  
Articular Cartilage ◽  
Tissue Repair ◽  
Cartilage Tissue ◽  
Low Oxygen ◽  
Fat Pad ◽  
Buccal Fat Pad ◽  
Low Oxygen Tension

scholarly journals Ways into Understanding HIF Inhibition

Cancers ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 159
Author(s):  
Tina Schönberger ◽  
Joachim Fandrey ◽  
Katrin Prost-Fingerle
Keyword(s):  
Protein Interactions ◽  
Target Genes ◽  
Protein Protein Interactions ◽  
Low Oxygen ◽  
Drug Candidates ◽  
Open Questions ◽  
Wide Range ◽  
Hif Pathway

Hypoxia is a key characteristic of tumor tissue. Cancer cells adapt to low oxygen by activating hypoxia-inducible factors (HIFs), ensuring their survival and continued growth despite this hostile environment. Therefore, the inhibition of HIFs and their target genes is a promising and emerging field of cancer research. Several drug candidates target protein–protein interactions or transcription mechanisms of the HIF pathway in order to interfere with activation of this pathway, which is deregulated in a wide range of solid and liquid cancers. Although some inhibitors are already in clinical trials, open questions remain with respect to their modes of action. New imaging technologies using luminescent and fluorescent methods or nanobodies to complement widely used approaches such as chromatin immunoprecipitation may help to answer some of these questions. In this review, we aim to summarize current inhibitor classes targeting the HIF pathway and to provide an overview of in vitro and in vivo techniques that could improve the understanding of inhibitor mechanisms. Unravelling the distinct principles regarding how inhibitors work is an indispensable step for efficient clinical applications and safety of anticancer compounds.

scholarly journals Generation of tetracycline-controllable CYP3A4-expressing Caco-2 cells by the piggyBac transposon system

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Moe Ichikawa ◽  
Hiroki Akamine ◽  
Michika Murata ◽  
Sumito Ito ◽  
Kazuo Takayama ◽  
...  
Keyword(s):  
Small Intestine ◽  
Drug Absorption ◽  
Cell Model ◽  
Negative Effects ◽  
Piggybac Transposon ◽  
Drug Metabolizing Enzyme ◽  
Metabolizing Enzyme ◽  
Cyp3a4 Expression

AbstractCaco-2 cells are widely used as an in vitro intestinal epithelial cell model because they can form a monolayer and predict drug absorption with high accuracy. However, Caco-2 cells hardly express cytochrome P450 (CYP), a drug-metabolizing enzyme. It is known that CYP3A4 is the dominant drug-metabolizing enzyme in human small intestine. In this study, we generated CYP3A4-expressing Caco-2 (CYP3A4-Caco-2) cells and attempted to establish a model that can simultaneously evaluate drug absorption and metabolism. CYP3A4-Caco-2 cells were generated by piggyBac transposon vectors. A tetracycline-controllable CYP3A4 expression cassette (tet-on system) was stably transduced into Caco-2 cells, thus regulating the levels of CYP3A4 expression depending on the doxycycline concentration. The CYP3A4 expression levels in CYP3A4-Caco-2 cells cultured in the presence of doxycycline were similar to or higher than those of adult small intestine. The CYP3A4-Caco-2 cells had enough ability to metabolize midazolam, a substrate of CYP3A4. CYP3A4 overexpression had no negative effects on cell proliferation, barrier function, and P-glycoprotein activity in Caco-2 cells. Thus, we succeeded in establishing Caco-2 cells with CYP3A4 metabolizing activity comparable to in vivo human intestinal tissue. This cell line would be useful in pharmaceutical studies as a model that can simultaneously evaluate drug absorption and metabolism.

scholarly journals Absorption of lactulose from mammalian gastrointestinal tract

1979 ◽  
Vol 41 (1) ◽  
pp. 47-51 ◽  
Author(s):  
D. F. Evered ◽  
F. Sadoogh-Abasian
Keyword(s):  
Small Intestine ◽  
Calcium Ions ◽  
Clinical Evidence ◽  
Buccal Cavity ◽  
Rat Small Intestine ◽  
Sodium Ions ◽  
Mode Of Transport ◽  
Poor Absorption

1. The disaccharide lactulose (galactosyl-β-1,4-fructose) was poorly absorbed from rat small intestine in vitro and human mouth in vivo.2. These results confirm indirect clinical evidence of poor absorption from the intestine.3. The presence of calcium ions, or absence of sodium ions, had no effect on lactulose absorption from the buccal cavity.4. The presence of ouabain, or absence of Na+, did not decrease the absorption of lactulose from small intestine.5. It is thought that the mode of transport, in both instances, is by passive diffusion with the concentration gradient.

Sign in / Sign up

Export Citation Format

Share Document