Weaning-associated feed deprivation stress causes microbiota disruptions in a novel mucin-containing in vitro model of the piglet colon (MPigut-IVM)

Abstract Background Risk factors for the etiology of post-weaning diarrhea, a major problem in swine industry associated with enormous economic losses, remain to be fully elucidated. In concordance with the ethical concerns raised by animal experiments, we developed a new in vitro model of the weaning piglet colon (MPigut-IVM) including a mucin bead compartment to reproduce the mucus surface from the gut to which gut microbes can adhere. Results Our results indicated that the MPigut-IVM is able to establish a representative piglet archaeal and bacterial colon microbiota in terms of taxonomic composition and function. The MPigut-IVM was consequently used to investigate the potential effects of feed deprivation, a common consequence of weaning in piglets, on the microbiota. The lack of nutrients in the MPigut-IVM led to an increased abundance of Prevotellaceae and Escherichia-Shigella and a decrease in Bacteroidiaceae and confirms previous in vivo findings. On top of a strong increase in redox potential, the feed deprivation stress induced modifications of microbial metabolite production such as a decrease in acetate and an increase in proportional valerate, isovalerate and isobutyrate production. Conclusions The MPigut-IVM is able to simulate luminal and mucosal piglet microbiota and represent an innovative tool for comparative studies to investigate the impact of weaning stressors on piglet microbiota. Besides, weaning-associated feed deprivation in piglets provokes disruptions of MPigut-IVM microbiota composition and functionality and could be implicated in the onset of post-weaning dysbiosis in piglets.

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Impact of the acidic environment on gene expression and functional parameters of tumors in vitro and in vivo

Journal of Experimental & Clinical Cancer Research ◽

10.1186/s13046-020-01815-4 ◽

2021 ◽

Vol 40 (1) ◽

Author(s):

Mandy Rauschner ◽

Luisa Lange ◽

Thea Hüsing ◽

Sarah Reime ◽

Alexander Nolze ◽

...

Keyword(s):

Gene Expression ◽

Cell Death ◽

Western Blot ◽

Tumor Cell ◽

Low Ph ◽

Strong Increase ◽

Acidic Ph ◽

The Impact

Abstract Background The low extracellular pH (pHe) of tumors resulting from glycolytic metabolism is a stress factor for the cells independent from concomitant hypoxia. The aim of the study was to analyze the impact of acidic pHe on gene expression on mRNA and protein level in two experimental tumor lines in vitro and in vivo and were compared to hypoxic conditions as well as combined acidosis+hypoxia. Methods Gene expression was analyzed in AT1 prostate and Walker-256 mammary carcinoma of the rat by Next Generation Sequencing (NGS), qPCR and Western blot. In addition, the impact of acidosis on tumor cell migration, adhesion, proliferation, cell death and mitochondrial activity was analyzed. Results NGS analyses revealed that 147 genes were uniformly regulated in both cell lines (in vitro) and 79 genes in both experimental tumors after 24 h at low pH. A subset of 25 genes was re-evaluated by qPCR and Western blot. Low pH consistently upregulated Aox1, Gls2, Gstp1, Ikbke, Per3, Pink1, Tlr5, Txnip, Ypel3 or downregulated Acat2, Brip1, Clspn, Dnajc25, Ercc6l, Mmd, Rif1, Zmpste24 whereas hypoxia alone led to a downregulation of most of the genes. Direct incubation at low pH reduced tumor cell adhesion whereas acidic pre-incubation increased the adhesive potential. In both tumor lines acidosis induced a G1-arrest (in vivo) of the cell cycle and a strong increase in necrotic cell death (but not in apoptosis). The mitochondrial O2 consumption increased gradually with decreasing pH. Conclusions These data show that acidic pHe in tumors plays an important role for gene expression independently from hypoxia. In parallel, acidosis modulates functional properties of tumors relevant for their malignant potential and which might be the result of pH-dependent gene expression.

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Effect of Common Anesthetics on Dendritic Properties in Layer 5 Neocortical Pyramidal Neurons

Journal of Neurophysiology ◽

10.1152/jn.01126.2007 ◽

2008 ◽

Vol 99 (3) ◽

pp. 1394-1407 ◽

Cited By ~ 28

Author(s):

Sarah Potez ◽

Matthew E. Larkum

Keyword(s):

High Frequency ◽

Pyramidal Neurons ◽

Animal Experiments ◽

Apical Dendrite ◽

Network Activity ◽

Calcium Spikes ◽

Firing Properties ◽

The Impact

Understanding the impact of active dendritic properties on network activity in vivo has so far been restricted to studies in anesthetized animals. However, to date no study has been made to determine the direct effect of the anesthetics themselves on dendritic properties. Here, we investigated the effects of three types of anesthetics commonly used for animal experiments (urethane, pentobarbital and ketamine/xylazine). We investigated the generation of calcium spikes, the propagation of action potentials (APs) along the apical dendrite and the somatic firing properties in the presence of anesthetics in vitro using dual somatodendritic whole cell recordings. Calcium spikes were evoked with dendritic current injection and high-frequency trains of APs at the soma. Surprisingly, we found that the direct actions of anesthetics on calcium spikes were very different. Two anesthetics (urethane and pentobarbital) suppressed dendritic calcium spikes in vitro, whereas a mixture of ketamine and xylazine enhanced them. Propagation of spikes along the dendrite was not significantly affected by any of the anesthetics but there were various changes in somatic firing properties that were highly dependent on the anesthetic. Last, we examined the effects of anesthetics on calcium spike initiation and duration in vivo using high-frequency trains of APs generated at the cell body. We found the same anesthetic-dependent direct effects in addition to an overall reduction in dendritic excitability in anesthetized rats with all three anesthetics compared with the slice preparation.

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Bovine sperm-oviduct interactions are characterized by specific sperm behaviour, ultrastructure and tubal reactions which are impacted by sex sorting

Scientific Reports ◽

10.1038/s41598-020-73592-1 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Miguel Camara Pirez ◽

Heather Steele ◽

Sven Reese ◽

Sabine Kölle

Keyword(s):

Beat Frequency ◽

Ciliary Beat Frequency ◽

Sperm Binding ◽

Tail Movement ◽

Bovine Spermatozoa ◽

Sperm Reservoir ◽

And Function ◽

The Impact

Abstract To date sperm-oviduct interactions have largely been investigated under in vitro conditions. Therefore we set out to characterize the behaviour of bovine spermatozoa within the sperm reservoir under near in vivo conditions and in real-time using a novel live cell imaging technology and a newly established fluorescent sperm binding assay. Sperm structure and tubal reactions after sperm binding were analysed using scanning and transmission electron microscopy and histochemistry. As a model to specify the impact of stress on sperm-oviduct interactions, frozen-thawed conventional and sex-sorted spermatozoa from the same bulls (n = 7) were co-incubated with oviducts obtained from cows immediately after slaughter. Our studies revealed that within the oviductal sperm reservoir agile (bound at a tangential angle of about 30°, actively beating undulating tail), lagging (bound at a lower angle, reduced tail movement), immotile (absence of tail movement) and hyperactivated (whip-like movement of tail) spermatozoa occur, the prevalence of which changes in a time-dependent pattern. After formation of the sperm reservoir, tubal ciliary beat frequency is significantly increased (p = 0.022) and the epithelial cells show increased activity of endoplasmic reticula. After sex sorting, spermatozoa occasionally display abnormal movement patterns characterized by a 360° rotating head and tail. Sperm binding in the oviduct is significantly reduced (p = 0.008) following sexing. Sex-sorted spermatozoa reveal deformations in the head, sharp bends in the tail and a significantly increased prevalence of damaged mitochondria (p < 0.001). Our results imply that the oviductal cells specifically react to the binding of spermatozoa, maintaining sperm survival within the tubal reservoir. The sex-sorting process, which is associated with mechanical, chemical and time stress, impacts sperm binding to the oviduct and mitochondrial integrity affecting sperm motility and function.

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The Impact of Uremic Toxins on Cerebrovascular and Cognitive Disorders

Toxins ◽

10.3390/toxins10070303 ◽

2018 ◽

Vol 10 (7) ◽

pp. 303 ◽

Cited By ~ 13

Author(s):

Maryam Assem ◽

Mathilde Lando ◽

Maria Grissi ◽

Saïd Kamel ◽

Ziad Massy ◽

...

Keyword(s):

Animal Experiments ◽

Cognitive Disorders ◽

Neurological Complications ◽

Cerebrovascular Diseases ◽

Uremic Toxins ◽

Current Evidence ◽

Cognitive Disorders And Dementia ◽

The Impact

Individuals at all stages of chronic kidney disease (CKD) have a higher risk of developing cognitive disorders and dementia. Stroke is also highly prevalent in this population and is associated with a higher risk of neurological deterioration, in-hospital mortality, and poor functional outcomes. Evidence from in vitro studies and in vivo animal experiments suggests that accumulation of uremic toxins may contribute to the pathogenesis of stroke and amplify vascular damage, leading to cognitive disorders and dementia. This review summarizes current evidence on the mechanisms by which uremic toxins may favour the occurrence of cerebrovascular diseases and neurological complications in CKD.

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IL-2 administration increases CD4+CD25hi Foxp3+ regulatory T cells in cancer patients

Blood ◽

10.1182/blood-2005-06-2399 ◽

2006 ◽

Vol 107 (6) ◽

pp. 2409-2414 ◽

Cited By ~ 433

Author(s):

Mojgan Ahmadzadeh ◽

Steven A. Rosenberg

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

Interleukin 2 ◽

Selective Inhibition ◽

High Dose ◽

Protein Levels ◽

And Function ◽

The Impact

Abstract Interleukin-2 (IL-2) is historically known as a T-cell growth factor. Accumulating evidence from knockout mice suggests that IL-2 is crucial for the homeostasis and function of CD4+CD25+ regulatory T cells in vivo. However, the impact of administered IL-2 in an immune intact host has not been studied in rodents or humans. Here, we studied the impact of IL-2 administration on the frequency and function of human CD4+CD25hi T cells in immune intact patients with melanoma or renal cancer. We found that the frequency of CD4+CD25hi T cells was significantly increased after IL-2 treatment, and these cells expressed phenotypic markers associated with regulatory T cells. In addition, both transcript and protein levels of Foxp3, a transcription factor exclusively expressed on regulatory T cells, were consistently increased in CD4 T cells following IL-2 treatment. Functional analysis of the increased number of CD4+CD25hi T cells revealed that this population exhibited potent suppressive activity in vitro. Collectively, our results demonstrate that administration of high-dose IL-2 increased the frequency of circulating CD4+CD25hi Foxp3+ regulatory T cells. Our findings suggest that selective inhibition of IL-2-mediated enhancement of regulatory T cells may improve the therapeutic effectiveness of IL-2 administration. (Blood. 2006;107:2409-2414)

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Androgen receptor modulates Foxp3 expression in CD4+CD25+Foxp3+ regulatory T-cells

Molecular Biology of the Cell ◽

10.1091/mbc.e14-08-1323 ◽

2015 ◽

Vol 26 (15) ◽

pp. 2845-2857 ◽

Cited By ~ 51

Author(s):

Magdalena Walecki ◽

Florian Eisel ◽

Jörg Klug ◽

Nelli Baal ◽

Agnieszka Paradowska-Dogan ◽

...

Keyword(s):

T Cells ◽

Androgen Receptor ◽

Treg Cell ◽

Foxp3 Expression ◽

Treg Cells ◽

Strong Increase ◽

Histone H4 ◽

And Function

CD4+CD25+Foxp3+ regulatory T (Treg) cells are able to inhibit proliferation and cytokine production in effector T-cells and play a major role in immune responses and prevention of autoimmune disease. A master regulator of Treg cell development and function is the transcription factor Foxp3. Several cytokines, such as TGF-β and IL-2, are known to regulate Foxp3 expression as well as methylation of the Foxp3 locus. We demonstrated previously that testosterone treatment induces a strong increase in the Treg cell population both in vivo and in vitro. Therefore we sought to investigate the direct effect of androgens on expression and regulation of Foxp3. We show a significant androgen-dependent increase of Foxp3 expression in human T-cells from women in the ovulatory phase of the menstrual cycle but not from men and identify a functional androgen response element within the Foxp3 locus. Binding of androgen receptor leads to changes in the acetylation status of histone H4, whereas methylation of defined CpG regions in the Foxp3 gene is unaffected. Our results provide novel evidence for a modulatory role of androgens in the differentiation of Treg cells.

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Long term exposure of human gut microbiota with high and low emulsifier sensitivity to soy lecithin in M-SHIME model.

10.1101/2021.12.16.472798 ◽

2021 ◽

Author(s):

Lisa Miclotte ◽

Ellen De Paepe ◽

Qiqiong Li ◽

Andreja Rajkovic ◽

John Van Camp ◽

...

Keyword(s):

Gut Microbiota ◽

Day Treatment ◽

Treatment Phase ◽

Microbial Composition ◽

Soy Lecithin ◽

Potential Health ◽

And Function ◽

The Impact

In the context of the potential health hazards related to food processing, dietary emulsifiers have been shown to alter the structure and function of the gut microbial community, both in vivo and in vitro. In mouse models, these emulsifier exposed gut microbiota were shown to contribute to gut inflammation. Several knowledge gaps remain to be addressed though. As such, the impact from a longer timeframe of exposure on the gut microbiota is not known and interindividual variability in microbiome response needs to be measured. To answer these research questions, in this study the faecal microbiota from two individuals, previously selected for high and low emulsifier sensitivity, were exposed to two concentrations of soy lecithin during a 7 day treatment phase in the dynamic mucosal simulator of the human intestinal microbial ecosystem (M-SHIME). The results showed mild effects from soy lecithin on the composition and functionality of these microbial communities, which depended on the original microbial composition. The effects also mostly levelled off after 3 days of exposure. The emulsifier sensitivity for which the microbiota were selected, was preserved. Some potentially concerning effects were also registered: butyrate levels, positively correlating with Faecalibacterium abundance, were lowered by soy lecithin. Also the abundance of the beneficial Bifidobacterium genus was lowered, while the abundance of the notorious unclassified Enterobacteriaceae was increased. Within the family of the unclassified Lachnospiraceae, several genera were either suppressed or stimulated. The effects that these microbial alterations would have on a living host is not yet certain, especially given the fact that large fractions of soy lecithins constituents can be absorbed. Nevertheless, choline and phosphatidylcholine, both primary and absorbable constituents of soy lecithin, have recently been linked to cardiovascular disease via the generation of TMA by the gut microbiota. Further studies that validate our findings and link them to potential health outcomes are thus justified.

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(Pro)renin receptor involves in myocardial fibrosis and oxidative stress in diabetic cardiomyopathy via the PRR–YAP pathway

Scientific Reports ◽

10.1038/s41598-021-82776-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Shiran Yu ◽

Xuefei Dong ◽

Min Yang ◽

Qingtao Yu ◽

Jie Xiong ◽

...

Keyword(s):

Oxidative Stress ◽

Myocardial Fibrosis ◽

Cardiac Fibroblasts ◽

Animal Experiments ◽

Specific Inhibitor ◽

Neonatal Rat ◽

Rnai Silencing ◽

The Impact

Abstract(Pro)renin receptor (PRR) and Yes-associated protein (YAP) play an important role in cardiovascular diseases. However, the role of PRR–YAP pathway in the pathogenesis of DCM is also not clear. We hypothesized that PRR–YAP pathway may promote pathological injuries in DCM by triggering redox. Wistar rats and neonatal rat cardiac fibroblasts were respectively used in vivo and in vitro studies. In order to observe the effects of PRR mediated YAP pathway on the pathogenesis of DCM, animal experiments were divided into 3 parts, including the evaluation the effects of PRR overexpression, PRR RNAi silencing and YAP RNAi silencing. Recombinant-adenoviruses-carried-PRR-gene (Ad-PRR), Ad-PRR-shRNA and lentivirus-carried-YAP-shRNA were constructed and the effects of PRR mediated YAP on the pathogenesis of DCM were evaluated. YAP specific inhibitor Verteporfin was also administrated in cardiac fibroblasts to explore the impact of PRR–YAP pathway on oxidative stress and myocardial fibrosis. The results displayed that PRR overexpression could enhance YAP expression but PRR RNAi silencing down-regulated its expression. Moreover, PRR overexpression could exacerbate oxidative stress and myocardial fibrosis in DCM, and these pathological changes could be rescued by YAP blockade. We concluded that PRR–YAP pathway plays a key role in the pathogenesis of DCM.

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Development and Physiological Functions of the Lymphatic System - Insights from Genetic Studies of Lymphedema

Physiological Reviews ◽

10.1152/physrev.00006.2020 ◽

2021 ◽

Author(s):

Silvia Martin-Almedina ◽

Peter Mortimer ◽

Pia Ostergaard

Keyword(s):

Lymphatic System ◽

Imaging Techniques ◽

The Body ◽

Genetic Studies ◽

Disease Mechanisms ◽

Primary Lymphedema ◽

And Function ◽

The Impact

Primary lymphedema is a long-term (chronic) condition characterized by tissue lymph retention and swelling that can affect any part of the body, although it usually develops in the arms or legs. Due to the relevant contribution of the lymphatic system to human physiology, while this review mainly focusses on the clinical and physiological aspects related to the regulation of fluid homeostasis and edema, clinicians need to know that the impact of lymphatic dysfunction with a genetic origin can be wide ranging. Lymphatic gene dysfunction can affect immune function so leading to infection; it can influence cancer development and spread; and it can determine fat transport so impacting on nutrition and obesity. Genetic studies and the development of imaging techniques for the assessment of lymphatic function have enabled the recognition of primary lymphedema as a heterogenic condition in terms of genetic causes and disease mechanisms. In this review, the known biological function of several genes crucial to the development and function of the lymphatic system are used as a basis for understanding normal lymphatic biology. The disease conditions originating from mutations in these genes are discussed together with a detailed clinical description of the phenotype and the up-to-date knowledge in terms of disease mechanisms acquired from in vitro and in vivo research models.

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Artificial skin composites

Annales Universitatis Mariae Curie-Sklodowska sectio AA – Chemia ◽

10.17951/aa.2018.73.1.51-60 ◽

2019 ◽

Vol 73 (1) ◽

pp. 51

Author(s):

Agata Ładniak

Keyword(s):

Wound Dressings ◽

Skin Damage ◽

Skin Substitutes ◽

Significant Deterioration ◽

Form And Function ◽

Potential Applications ◽

And Function ◽

The Impact

Skin injuries are a health problem and can lead to serious, significant deterioration in the quality of life and, consequently, even illness and disability. Therefore, after wounding, immediate regeneration of the tissue is necessary to avoid further complications and pathogenesis. Consequently, many wound healing strategies have been developed, leading to the progress in constructing of multifunctional tissue substitutes for the skin, biomembranes, scaffolds and intelligent dressings. The field of science focusing on the creation of the above-mentioned products is tissue engineering (TE). Its main goal is to find a system that is able to replace or be a model that perfectly mimics the form and function of the skin. Research carried out on such constructs is mainly based on the analysis of mechanical properties (porosity, elasticity), as well as the assessment of the impact of individual components on processes related to the formation of new tissue as cell proliferation and differentiation, proliferation, angiogenesis - through in vivo studies (using animal models: mice, New Zealand rabbits) and in vitro (most often using mouse fibroblasts - L929). Skin constructions may have potential applications as wound dressings or skin substitutes in cases of severe skin damage.

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