Dietary excess regulates absorption and surface of gut epithelium through intestinal PPARα

AbstractIntestinal surface changes in size and function, but what propels these alterations and what are their metabolic consequences is unknown. Here we report that the food amount is a positive determinant of the gut surface area contributing to an increased absorptive function, reversible by reducing daily food. While several upregulated intestinal energetic pathways are dispensable, the intestinal PPARα is instead necessary for the genetic and environment overeating–induced increase of the gut absorptive capacity. In presence of dietary lipids, intestinal PPARα knock-out or its pharmacological antagonism suppress intestinal crypt expansion and shorten villi in mice and in human intestinal biopsies, diminishing the postprandial triglyceride transport and nutrient uptake. Intestinal PPARα ablation limits systemic lipid absorption and restricts lipid droplet expansion and PLIN2 levels, critical for droplet formation. This improves the lipid metabolism, and reduces body adiposity and liver steatosis, suggesting an alternative target for treating obesity.

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Deficiency of the onco-miRNA cluster, miR-106b∼25, causes oligozoospermia and the cooperative action of miR-106b∼25 and miR-17∼92 is required to maintain male fertility

MHR Basic science of reproductive medicine ◽

10.1093/molehr/gaaa027 ◽

2020 ◽

Vol 26 (6) ◽

pp. 389-401

Author(s):

Alicia Hurtado ◽

Rogelio Palomino ◽

Ina Georg ◽

Miguel Lao ◽

Francisca M Real ◽

...

Keyword(s):

Male Fertility ◽

Molecular Mechanisms ◽

Mirna Cluster ◽

Knock Out ◽

Cooperative Action ◽

Mouse Mutants ◽

New Genes ◽

Mirna Clusters ◽

Testicular Histology ◽

And Function

Abstract The identification of new genes involved in sexual development and gonadal function as potential candidates causing male infertility is important for both diagnostic and therapeutic purposes. Deficiency of the onco-miRNA cluster miR-17∼92 has been shown to disrupt spermatogenesis, whereas mutations in its paralog cluster, miR-106b∼25, that is expressed in the same cells, were reported to have no effect on testis development and function. The aim of this work is to determine the role of these two miRNA clusters in spermatogenesis and male fertility. For this, we analyzed miR-106b∼25 and miR-17∼92 single and double mouse mutants and compared them to control mice. We found that miR-106b∼25 knock out testes show reduced size, oligozoospermia and altered spermatogenesis. Transcriptomic analysis showed that multiple molecular pathways are deregulated in these mutant testes. Nevertheless, mutant males conserved normal fertility even when early spermatogenesis and other functions were disrupted. In contrast, miR-17∼92+/−; miR-106b∼25−/− double mutants showed severely disrupted testicular histology and significantly reduced fertility. Our results indicate that miR-106b∼25 and miR-17∼92 ensure accurate gene expression levels in the adult testis, keeping them within the required thresholds. They play a crucial role in testis homeostasis and are required to maintain male fertility. Hence, we have identified new candidate genetic factors to be screened in the molecular diagnosis of human males with reproductive disorders. Finally, considering the well-known oncogenic nature of these two clusters and the fact that patients with reduced fertility are more prone to testicular cancer, our results might also help to elucidate the molecular mechanisms linking both pathologies.

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FKBP51 Modulates Hippocampal Size and Function in Post-translational Regulation of Parkin

10.21203/rs.3.rs-493867/v1 ◽

2021 ◽

Author(s):

Bin Qiu ◽

Zhaohui Zhong ◽

Shawn Righter ◽

Yuxue Xu ◽

Jun Wang ◽

...

Keyword(s):

Hippocampal Neurons ◽

Translational Regulation ◽

Disease Onset ◽

Fold Increase ◽

Knock Out ◽

Fk506 Binding Protein ◽

Protein Levels ◽

And Function

Abstract FK506-binding protein 51 (encoded by Fkpb51) has been associated with stress-related mental illness. To identify its function, we studied the morphological consequences of Fkbp51 deletion. Artificial Intelligence-assist morphological analysis identified that Fkbp51 knock-out (KO) mice possess more elongated CA and DG but shorter in height in coronal section when compared to WT. Primary cultured Fkbp51 KO hippocampal neurons were shown to exhibit larger dendritic outgrowth than wild-type (WT) controls, pharmacological manipulation experiments suggest that this may occur through regulation of microtubule-associated protein. Both in vitro primary culture and in vivo labeling support that FKBP51 regulates microtubule-associated protein expression. Furthermore, in the absence of differences in mRNA expression, Fkbp51 KO hippocampus exhibited decreases in βIII-tubulin, MAP2, and Tau protein levels, but a greater than 2.5-fold increase in Parkin protein. Overexpression and knock-down FKBP51 demonstrated that FKBP51 negatively regulates Parkin in a dose-dependent and ubiquitin-mediated manner. These results indicate a potential novel post-translational regulatory of Parkin by FKBP51 and significance of their interaction on disease onset.

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Absence of orthogonal arrays in kidney, brain and muscle from transgenic knockout mice lacking water channel aquaporin-4

Journal of Cell Science ◽

10.1242/jcs.110.22.2855 ◽

1997 ◽

Vol 110 (22) ◽

pp. 2855-2860 ◽

Cited By ~ 1

Author(s):

J.M. Verbavatz ◽

T. Ma ◽

R. Gobin ◽

A.S. Verkman

Keyword(s):

Cho Cells ◽

Collecting Duct ◽

Water Channel ◽

Freeze Fracture ◽

Orthogonal Arrays ◽

Knock Out ◽

Orthogonal Arrays Of Particles ◽

Freeze Fracture Electron Microscopy ◽

Knock Out Mice ◽

And Function

Freeze-fracture electron microscopy (FFEM) of kidney collecting duct, muscle, astrocytes in brain, and other mammalian tissues has revealed regular square arrays of intramembrane particles called orthogonal arrays of particles (OAPs). Their possible role in membrane structure and transport have been proposed, and their absence or decrease has been noted in a variety of hereditary and acquired diseases. A transgenic mouse lacking water channel AQP4 was used to show that AQP4 is the OAP protein. FFEM was done on kidney, skeletal muscle, and brain from AQP4 wild-type [+/+], heterozygous [+/−] and knock-out [-/-] mice. The [-/-] mice did not express detectable AQP4 protein, but were grossly indistinguishable from [+/+] mice. FFEM was done on blinded samples of kidney, brain and muscle from 9 mice. In all 6 kidney samples from [+/+] and [+/−] mice, OAPs similar to those in AQP4-transfected CHO cells were found in basolateral membranes of collecting duct principal cells. In all muscle and brain samples from [+/+] and [+/−] mice, OAPs of identical ultrastructure to those in kidney were seen, but in smaller patch sizes. OAPs were not seen in any sample from [-/-] mice. Label-fracture analysis using a peptide-derived AQP4 polyclonal antibody showed immunogold labeling of OAPs in AQP4-expressing CHO cells. These studies provide direct evidence that AQP4 is required for formation of OAPs and is a component of OAPs, thus establishing the identity and function of OAPs.

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In Vitro Digestion of Grape Seed Oil Inhibits Phospholipid-Regulating Effects of Oxidized Lipids

Biomolecules ◽

10.3390/biom10050708 ◽

2020 ◽

Vol 10 (5) ◽

pp. 708 ◽

Cited By ~ 2

Author(s):

Sarah Fruehwirth ◽

Sofie Zehentner ◽

Mohammed Salim ◽

Sonja Sterneder ◽

Johanna Tiroch ◽

...

Keyword(s):

Fatty Acids ◽

Seed Oil ◽

In Vitro Digestion ◽

Grape Seed ◽

Dietary Lipids ◽

Lipid Absorption ◽

Oxidized Lipids ◽

Grape Seed Oil ◽

Oxidized Triacylglycerols

The intake of dietary lipids is known to affect the composition of phospholipids in gastrointestinal cells, thereby influencing passive lipid absorption. However, dietary lipids rich in polyunsaturated fatty acids, such as vegetable oils, are prone to oxidation. Studies investigating the phospholipid-regulating effect of oxidized lipids are lacking. We aimed at identifying the effects of oxidized lipids from moderately (18.8 ± 0.39 meq O2/kg oil) and highly (28.2 ± 0.39 meq O2/kg oil) oxidized and in vitro digested cold-pressed grape seed oils on phospholipids in human gastric tumor cells (HGT-1). The oils were analyzed for their antioxidant constituents as well as their oxidized triacylglycerol profile by LC-MS/MS before and after a simulated digestion. The HGT-1 cells were treated with polar oil fractions containing epoxidized and hydroperoxidized triacylglycerols for up to six hours. Oxidized triacylglycerols from grape seed oil were shown to decrease during the in vitro digestion up to 40% in moderately and highly oxidized oil. The incubation of HGT-1 cells with oxidized lipids from non-digested oils induced the formation of cellular phospholipids consisting of unsaturated fatty acids, such as phosphocholines PC (18:1/22:6), PC (18:2/0:0), phosphoserine PS (42:8) and phosphoinositol PI (20:4/0:0), by about 40%–60%, whereas the incubation with the in vitro digested oils did not affect the phospholipid metabolism. Hence, the gastric conditions inhibited the phospholipid-regulating effect of oxidized triacylglycerols (oxTAGs), with potential implications in lipid absorption.

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N-Cadherin Is Critical for the Survival of Germ Cells, the Formation of Steroidogenic Cells, and the Architecture of Developing Mouse Gonads

Cells ◽

10.3390/cells8121610 ◽

2019 ◽

Vol 8 (12) ◽

pp. 1610 ◽

Cited By ~ 2

Author(s):

Rafal P. Piprek ◽

Michal Kolasa ◽

Dagmara Podkowa ◽

Malgorzata Kloc ◽

Jacek Z. Kubiak

Keyword(s):

Germ Cells ◽

Hormonal Regulation ◽

Critical Role ◽

Somatic Cells ◽

Gonad Development ◽

Knock Out ◽

Gonad Differentiation ◽

Steroidogenic Cells ◽

The Individual ◽

And Function

Normal gonad development assures the fertility of the individual. The properly functioning gonads must contain a sufficient number of the viable germ cells, possess a correct architecture and tissue structure, and assure the proper hormonal regulation. This is achieved by the interplay between the germ cells and different types of somatic cells. N-cadherin coded by the Cdh2 gene plays a critical role in this interplay. To gain an insight into the role of N-cadherin in the development of mouse gonads, we used the Cre-loxP system to knock out N-cadherin separately in two cell lines: the SF1+ somatic cells and the OCT4+ germ cells. We observed that N-cadherin plays a key role in the survival of both female and male germ cells. However, the N-cadherin is not necessary for the differentiation of the Sertoli cells or the initiation of the formation of testis cords or ovigerous cords. In the later stages of gonad development, N-cadherin is important for the maintenance of testis cord structure and is required for the formation of steroidogenic cells. In the ovaries, N-cadherin is necessary for the formation of the ovarian follicles. These results indicate that N-cadherin plays a major role in gonad differentiation, structuralization, and function.

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CRISPR/Cas9 Genome Editing Technology: A Valuable Tool for Understanding Plant Cell Wall Biosynthesis and Function

Frontiers in Plant Science ◽

10.3389/fpls.2020.589517 ◽

2020 ◽

Vol 11 ◽

Author(s):

Yuan Zhang ◽

Allan M. Showalter

Keyword(s):

Cell Wall ◽

Genome Editing ◽

Gene Targeting ◽

Plant Cell ◽

Plant Cell Wall ◽

Cell Structure ◽

Higher Order ◽

Knock Out ◽

Genetic Crossing ◽

And Function

For the past 5 years, clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) technology has appeared in the molecular biology research spotlight. As a game-changing player in genome editing, CRISPR/Cas9 technology has revolutionized animal research, including medical research and human gene therapy as well as plant science research, particularly for crop improvement. One of the most common applications of CRISPR/Cas9 is to generate genetic knock-out mutants. Recently, several multiplex genome editing approaches utilizing CRISPR/Cas9 were developed and applied in various aspects of plant research. Here we summarize these approaches as they relate to plants, particularly with respect to understanding the biosynthesis and function of the plant cell wall. The plant cell wall is a polysaccharide-rich cell structure that is vital to plant cell formation, growth, and development. Humans are heavily dependent on the byproducts of the plant cell wall such as shelter, food, clothes, and fuel. Genes involved in the assembly of the plant cell wall are often highly redundant. To identify these redundant genes, higher-order knock-out mutants need to be generated, which is conventionally done by genetic crossing. Compared with genetic crossing, CRISPR/Cas9 multi-gene targeting can greatly shorten the process of higher-order mutant generation and screening, which is especially useful to characterize cell wall related genes in plant species that require longer growth time. Moreover, CRISPR/Cas9 makes it possible to knock out genes when null T-DNA mutants are not available or are genetically linked. Because of these advantages, CRISPR/Cas9 is becoming an ideal and indispensable tool to perform functional studies in plant cell wall research. In this review, we provide perspectives on how to design CRISPR/Cas9 to achieve efficient gene editing and multi-gene targeting in plants. We also discuss the recent development of the virus-based CRISPR/Cas9 system and the application of CRISPR/Cas9 to knock in genes. Lastly, we summarized current progress on using CRISPR/Cas9 for the characterization of plant cell wall-related genes.

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Dietary lipids, gut microbiota and lipid metabolism

Reviews in Endocrine and Metabolic Disorders ◽

10.1007/s11154-019-09512-0 ◽

2019 ◽

Vol 20 (4) ◽

pp. 461-472 ◽

Cited By ~ 40

Author(s):

Marc Schoeler ◽

Robert Caesar

Keyword(s):

Fatty Acids ◽

Lipid Metabolism ◽

Liver Disease ◽

Gut Microbiota ◽

Short Chain Fatty Acids ◽

Dietary Lipids ◽

Lipid Levels ◽

And Function ◽

Host Metabolism ◽

Secondary Bile Acids

Abstract The gut microbiota is a central regulator of host metabolism. The composition and function of the gut microbiota is dynamic and affected by diet properties such as the amount and composition of lipids. Hence, dietary lipids may influence host physiology through interaction with the gut microbiota. Lipids affect the gut microbiota both as substrates for bacterial metabolic processes, and by inhibiting bacterial growth by toxic influence. The gut microbiota has been shown to affect lipid metabolism and lipid levels in blood and tissues, both in mice and humans. Furthermore, diseases linked to dyslipidemia, such as non-alcoholic liver disease and atherosclerosis, are associated with changes in gut microbiota profile. The influence of the gut microbiota on host lipid metabolism may be mediated through metabolites produced by the gut microbiota such as short-chain fatty acids, secondary bile acids and trimethylamine and by pro-inflammatory bacterially derived factors such as lipopolysaccharide. Here we will review the association between gut microbiota, dietary lipids and lipid metabolism

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Specific expression and function of inositol 1,4,5-trisphosphate 3-kinase C (ITPKC) in wild type and knock-out mice

Advances in Biological Regulation ◽

10.1016/j.jbior.2016.03.001 ◽

2016 ◽

Vol 62 ◽

pp. 1-10 ◽

Cited By ~ 10

Author(s):

Ariane Scoumanne ◽

Patricia Molina-Ortiz ◽

Daniel Monteyne ◽

David Perez-Morga ◽

Christophe Erneux ◽

...

Keyword(s):

Wild Type ◽

Specific Expression ◽

Knock Out ◽

Kinase C ◽

Inositol 1,4,5 Trisphosphate ◽

Knock Out Mice ◽

And Function

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The development of functional B lymphocytes in conditional PU.1 knock-out mice

Blood ◽

10.1182/blood-2005-01-0283 ◽

2005 ◽

Vol 106 (6) ◽

pp. 2083-2090 ◽

Cited By ~ 55

Author(s):

Matthew Polli ◽

Aleksandar Dakic ◽

Amanda Light ◽

Li Wu ◽

David M. Tarlinton ◽

...

Keyword(s):

B Cells ◽

B Cell ◽

B Lymphocytes ◽

Fetal Liver ◽

Cell Receptor ◽

Interleukin 4 ◽

Knock Out ◽

B Lineage ◽

And Function

Abstract An abundance of research has entrenched the view that the Ets domain containing transcription factor PU.1 is fundamental to the development and function of B lymphocytes. In this study, we have made use of a conditional PU.1 allele to test this notion. Complete deletion of PU.1 resulted in the loss of B cells and all other lineage-positive cells in the fetal liver and death between E18.5 and birth; however, specific deletion of PU.1 in the B lineage had no effect on B-cell development. Furthermore, deletion of PU.1 in B cells did not compromise their ability to establish and maintain an immune response. An increased level of apoptosis was observed in vitro upon B-cell receptor (BCR) cross-linking; however, this was partially rescued by interleukin-4 (IL-4). These findings suggest that PU.1 is not essential for the development of functional B lymphocytes beyond the pre-B stage. (Blood. 2005;106:2083-2090)

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