Injury-stimulated Hedgehog signaling promotes regenerative proliferation of Drosophila intestinal stem cells

Many adult tissues are maintained by resident stem cells that elevate their proliferation in response to injury. The regulatory mechanisms underlying regenerative proliferation are still poorly understood. Here we show that injury induces Hedgehog (Hh) signaling in enteroblasts (EBs) to promote intestinal stem cell (ISC) proliferation in Drosophila melanogaster adult midgut. Elevated Hh signaling by patched (ptc) mutations drove ISC proliferation noncell autonomously. Inhibition of Hh signaling in the ISC lineage compromised injury-induced ISC proliferation but had little if any effect on homeostatic proliferation. Hh signaling acted in EBs to regulate the production of Upd2, which activated the JAK–STAT pathway to promote ISC proliferation. Furthermore, we show that Hh signaling is stimulated by DSS through the JNK pathway and that inhibition of Hh signaling in EBs prevented DSS-stimulated ISC proliferation. Hence, our study uncovers a JNK–Hh–JAK–STAT signaling axis in the regulation of regenerative stem cell proliferation.

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Aneuploidy in intestinal stem cells promotes gut dysplasia in Drosophila

The Journal of Cell Biology ◽

10.1083/jcb.201804205 ◽

2018 ◽

Vol 217 (11) ◽

pp. 3930-3946 ◽

Cited By ~ 10

Author(s):

Luís Pedro Resende ◽

Augusta Monteiro ◽

Rita Brás ◽

Tatiana Lopes ◽

Claudio E. Sunkel

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Spindle Assembly Checkpoint ◽

Cell Types ◽

Intestinal Stem Cells ◽

Jnk Pathway ◽

Posterior Midgut ◽

Stem Cell Populations ◽

Different Cell Types ◽

Adult Drosophila

Aneuploidy is associated with different human diseases including cancer. However, different cell types appear to respond differently to aneuploidy, either by promoting tumorigenesis or causing cell death. We set out to study the behavior of adult Drosophila melanogaster intestinal stem cells (ISCs) after induction of chromosome missegregation either by abrogation of the spindle assembly checkpoint or through kinetochore disruption or centrosome amplification. These conditions induce moderate levels of aneuploidy in ISCs, and we find no evidence of apoptosis. Instead, we observe a significant accumulation of ISCs associated with increased stem cell proliferation and an excess of enteroendocrine cells. Moreover, aneuploidy causes up-regulation of the JNK pathway throughout the posterior midgut, and specific inhibition of JNK signaling in ISCs is sufficient to prevent dysplasia. Our findings highlight the importance of understanding the behavior of different stem cell populations to aneuploidy and how these can act as reservoirs for genomic alterations that can lead to tissue pathologies.

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Immunostaining of Lgr5, an Intestinal Stem Cell Marker, in Normal and Premalignant Human Gastrointestinal Tissue

The Scientific World JOURNAL ◽

10.1100/tsw.2008.148 ◽

2008 ◽

Vol 8 ◽

pp. 1168-1176 ◽

Cited By ~ 76

Author(s):

Laren Becker ◽

Qin Huang ◽

Hiroshi Mashimo

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Stem Cell Niche ◽

Intestinal Stem Cells ◽

Stem Cell Marker ◽

Tumor Initiating Cells ◽

Colonic Adenomas ◽

Potential Marker ◽

Cell Niche ◽

Crypt Base

Lgr5 has recently been identified as a murine marker of intestinal stem cells. Its expression has not been well characterized in human gastrointestinal tissues, but has been reported in certain cancers. With the increasing appreciation for the role of cancer stem cells or tumor-initiating cells in certain tumors, we sought to explore the expression of Lgr5 in normal and premalignant human gastrointestinal tissues. Using standard immunostaining, we compared expression of Lgr5 in normal colon and small intestine vs. small intestinal and colonic adenomas and Barrett's esophagus. In the normal tissue, Lgr5 was expressed in the expected stem cell niche, at the base of crypts, as seen in mice. However, in premalignant lesions, Lgr5+cells were not restricted to the crypt base. Additionally, their overall numbers were increased. In colonic adenomas, Lgr5+cells were commonly found clustered at the luminal surface and rarely at the crypt base. Finally, we compared immunostaining of Lgr5 with that of CD133, a previously characterized marker for tumor-initiating cells in colon cancer, and found that they identified distinct subpopulations of cells that were in close proximity, but did not costain. Our findings suggest that (1) Lgr5 is a potential marker of intestinal stem cells in humans and (2) loss of restriction to the stem cell niche is an early event in the premalignant transformation of stem cells and may play a role in carcinogenesis.

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Study on the Therapeutic Mechanism of LXGYD on Intestinal Stem Cells and Tight Junction Proteins in GI-ARS Rats

10.21203/rs.3.rs-1112710/v1 ◽

2021 ◽

Author(s):

Ziqiao Yan ◽

Bofeng Yin ◽

Yuguo Wang ◽

Jian Feng ◽

Qianyu Yang ◽

...

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Health Status ◽

Tight Junction ◽

Western Blotting ◽

Rat Model ◽

Protective Efficacy ◽

Intestinal Stem Cells ◽

Pathological Analysis ◽

Chinese Herbal

Abstract Background: Gastrointestinal acute radiation injury syndrome (GI-ARS) is potentially lethal and may occur after exposure to high radiation doses. Various chemical and biological agents have been developed to treat GI-ARS. However, their clinical utility is limited as they induce serious adverse reactions at their effective doses. Chinese herbal medicines have attracted attention because of their protective efficacy and low toxicity in radiation exposure treatment. However, their cellular and molecular mechanisms remain unknown. Here, we investigated the effects of the Chinese herbal Liangxue-Guyuan-Yishen decoction (LXGYD) on the intestinal stem cells and signal pathways of a GI-ARS rat model. Currently, there are limited treatment methods available globally; LXGYD might be a potential therapeutic option for patients with GI-ARS. Methods: The rat GI-ARS model was prepared by whole-body irradiation with 10-Gy of 60Co-γ rays. Various LXGYD concentrations were intragastrically administered to the irradiated rats. Health status and survival of the rats were evaluated and the protective efficacy of LXGYD on the intestines was assayed by pathological analysis. The active principles in LXGYD were detected by liquid chromatography-mass spectrometry (LC-MS) and their potential targets and pathways were screened by network pharmacological analysis. Intestinal stem cell proliferation, intestinal epithelial tight junction (TJ) protein expression, and regulatory pathways were explored by immunohistochemistry (IHC), western blotting (WB), and real-time quantitative polymerase chain reaction (RT-qPCR), respectively.Results: LXGYD administration significantly improved health status and survival in GI-ARS rats. The pathological analysis showed that LXGYD ameliorated radiation-induced intestinal injury. The LXGYD infusion significantly promoted LGR5+ stem cell regeneration in the ileal crypts, upregulated TJ proteins, and accelerated crypt reconstruction in the irradiated rats in a dose-dependent manner. LC-MS revealed ≥ 13 LXGYD constituents that might contribute to its protective effects. Involvement of the WNT and MEK/ERK pathways in intestinal repair and recovery were screened by network pharmacology analysis and validated by western blotting.Conclusions: The present study disclosed a heretofore unrecognized role of the Chinese herbal LXGYD in rescuing the intestinal stem cells of a GI-ARS rat model. It also showed that the WNT and MEK/ERK pathways may be involved in LXGYD-mediated intestinal regeneration in GI-ARS.

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Contribution of Resident Stem Cells to Liver and Biliary Tree Regeneration in Human Diseases

International Journal of Molecular Sciences ◽

10.3390/ijms19102917 ◽

2018 ◽

Vol 19 (10) ◽

pp. 2917 ◽

Cited By ~ 20

Author(s):

Diletta Overi ◽

Guido Carpino ◽

Vincenzo Cardinale ◽

Antonio Franchitto ◽

Samira Safarikia ◽

...

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Progenitor Cells ◽

Human Liver ◽

Progenitor Cell ◽

Biliary Tree ◽

Tree Regeneration ◽

Multipotent Stem Cells ◽

Resident Stem Cells ◽

Stem Cell Niches

Two distinct stem/progenitor cell populations of biliary origin have been identified in the adult liver and biliary tree. Hepatic Stem/progenitor Cells (HpSCs) are bipotent progenitor cells located within the canals of Hering and can be differentiated into mature hepatocytes and cholangiocytes; Biliary Tree Stem/progenitor Cells (BTSCs) are multipotent stem cells located within the peribiliary glands of large intrahepatic and extrahepatic bile ducts and able to differentiate into hepatic and pancreatic lineages. HpSCs and BTSCs are endowed in a specialized niche constituted by supporting cells and extracellular matrix compounds. The actual contribution of these stem cell niches to liver and biliary tree homeostatic regeneration is marginal; this is due to the high replicative capabilities and plasticity of mature parenchymal cells (i.e., hepatocytes and cholangiocytes). However, the study of human liver and biliary diseases disclosed how these stem cell niches are involved in the regenerative response after extensive and/or chronic injuries, with the activation of specific signaling pathways. The present review summarizes the contribution of stem/progenitor cell niches in human liver diseases, underlining mechanisms of activation and clinical implications, including fibrogenesis and disease progression.

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Unveiling role of sphingosine-1-phosphate receptor 2 as a brake of epithelial stem cell proliferation and a tumor suppressor in colorectal cancer

Journal of Experimental & Clinical Cancer Research ◽

10.1186/s13046-020-01740-6 ◽

2020 ◽

Vol 39 (1) ◽

Author(s):

Luciana Petti ◽

Giulia Rizzo ◽

Federica Rubbino ◽

Sudharshan Elangovan ◽

Piergiuseppe Colombo ◽

...

Keyword(s):

Colorectal Cancer ◽

Stem Cells ◽

Cell Proliferation ◽

Stem Cell ◽

Tumor Suppressor ◽

Normal Mucosa ◽

Intestinal Stem Cells ◽

Intestinal Epithelial ◽

Sphingosine 1 Phosphate

Abstract Background Sphingosine-1-phosphate receptor 2 (S1PR2) mediates pleiotropic functions encompassing cell proliferation, survival, and migration, which become collectively de-regulated in cancer. Information on whether S1PR2 participates in colorectal carcinogenesis/cancer is scanty, and we set out to fill the gap. Methods We screened expression changes of S1PR2 in human CRC and matched normal mucosa specimens [N = 76]. We compared CRC arising in inflammation-driven and genetically engineered models in wild-type (S1PR2+/+) and S1PR2 deficient (S1PR2−/−) mice. We reconstituted S1PR2 expression in RKO cells and assessed their growth in xenografts. Functionally, we mimicked the ablation of S1PR2 in normal mucosa by treating S1PR2+/+ organoids with JTE013 and characterized intestinal epithelial stem cells isolated from S1PR2−/−Lgr5-EGFP- mice. Results S1PR2 expression was lost in 33% of CRC; in 55%, it was significantly decreased, only 12% retaining expression comparable to normal mucosa. Both colitis-induced and genetic Apc+/min mouse models of CRC showed a higher incidence in size and number of carcinomas and/or high-grade adenomas, with increased cell proliferation in S1PR2−/− mice compared to S1PR2+/+ controls. Loss of S1PR2 impaired mucosal regeneration, ultimately promoting the expansion of intestinal stem cells. Whereas its overexpression attenuated cell cycle progression, it reduced the phosphorylation of AKT and augmented the levels of PTEN. Conclusions In normal colonic crypts, S1PR2 gains expression along with intestinal epithelial cells differentiation, but not in intestinal stem cells, and contrasts intestinal tumorigenesis by promoting epithelial differentiation, preventing the expansion of stem cells and braking their malignant transformation. Targeting of S1PR2 may be of therapeutic benefit for CRC expressing high Lgr5. Graphical Abstract. Schematic drawing of the role of S1PR2 in normal mucosa and colorectal cancer. In the normal mucosa, S1PR2 is highly expressed by differentiated cells at the upper region of both colon and intestinal crypts (S1PR2 ON), but not by the undifferentiated stem cell at the base of the crypts (S1PR2 OFF), in which acts as a negative proliferative regulator promoting epithelial differentiation. Its loss leads to the expansion of stem cells and reduced levels of PTEN and Axin-2, two negative regulators respectively of PI3K/AKT and Wnt signaling that control β-catenin signaling. The translocation of β-catenin into the nucleus promotes the transcription of target genes involved in the proliferation and malignant transformation. Thereby, S1PR2 works in the intestine as a tumor suppressor

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Neural Differentiation of Human Adipose Tissue-Derived Stem Cells Involves Activation of the Wnt5a/JNK Signalling

Stem Cells International ◽

10.1155/2015/178618 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 23

Author(s):

Sujeong Jang ◽

Jong-Seong Park ◽

Han-Seong Jeong

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Neural Differentiation ◽

Neural Induction ◽

Stem Cell Differentiation ◽

Human Adipose Tissue ◽

Pcr Analysis ◽

Rt Pcr ◽

Jnk Pathway ◽

Expression Levels

Stem cells are a powerful resource for cell-based transplantation therapies, but understanding of stem cell differentiation at the molecular level is not clear yet. We hypothesized that the Wnt pathway controls stem cell maintenance and neural differentiation. We have characterized the transcriptional expression of Wnt during the neural differentiation of hADSCs. After neural induction, the expressions of Wnt2, Wnt4, and Wnt11 were decreased, but the expression of Wnt5a was increased compared with primary hADSCs in RT-PCR analysis. In addition, the expression levels of most Fzds and LRP5/6 ligand were decreased, but not Fzd3 and Fzd5. Furthermore, Dvl1 and RYK expression levels were downregulated in NI-hADSCs. There were no changes in the expression of ß-catenin and GSK3ß. Interestingly, Wnt5a expression was highly increased in NI-hADSCs by real time RT-PCR analysis and western blot. Wnt5a level was upregulated after neural differentiation and Wnt3, Dvl2, and Naked1 levels were downregulated. Finally, we found that the JNK expression was increased after neural induction and ERK level was decreased. Thus, this study shows for the first time how a single Wnt5a ligand can activate the neural differentiation pathway through the activation of Wnt5a/JNK pathway by binding Fzd3 and Fzd5 and directing Axin/GSK-3ß in hADSCs.

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Toll-like receptor 4 (TLR4) is expressed on intestinal stem cells and inhibits stem cell proliferation in the pathogenesis of intestinal inflammation

Journal of the American College of Surgeons ◽

10.1016/j.jamcollsurg.2011.06.201 ◽

2011 ◽

Vol 213 (3) ◽

pp. S85 ◽

Cited By ~ 2

Author(s):

Matthew D. Neal ◽

Chhinder P. Sodhi ◽

Ibrahim Yazji ◽

Anthony M. Russo ◽

Richard Siggers ◽

...

Keyword(s):

Stem Cells ◽

Cell Proliferation ◽

Stem Cell ◽

Intestinal Inflammation ◽

Intestinal Stem Cells ◽

Toll Like Receptor ◽

Toll Like Receptor 4 ◽

Stem Cell Proliferation

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Role of the Hedgehog Signaling Pathway in Regulating the Behavior of Germline Stem Cells

Stem Cells International ◽

10.1155/2017/5714608 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Shiqin Li ◽

Meng Wang ◽

Yanghui Chen ◽

Wei Wang ◽

Junying Wu ◽

...

Keyword(s):

Stem Cells ◽

Signaling Pathway ◽

Hedgehog Signaling ◽

Adult Stem Cells ◽

Reproductive Function ◽

Future Research ◽

Germline Stem Cells ◽

Proliferation And Differentiation ◽

Hh Signaling

Germline stem cells (GSCs) are adult stem cells that are responsible for the production of gametes and include spermatogonial stem cells (SSCs) and ovarian germline stem cells (OGSCs). GSCs are located in a specialized microenvironment in the gonads called the niche. Many recent studies have demonstrated that multiple signals in the niche jointly regulate the proliferation and differentiation of GSCs, which is of significance for reproductive function. Previous studies have demonstrated that the hedgehog (Hh) signaling pathway participates in the proliferation and differentiation of various stem cells, including GSCs in Drosophila and male mammals. Furthermore, the discovery of mammalian OGSCs challenged the traditional opinion that the number of primary follicles is fixed in postnatal mammals, which is of significance for the reproductive ability of female mammals and the treatment of diseases related to germ cells. Meanwhile, it still remains to be determined whether the Hh signaling pathway participates in the regulation of the behavior of OGSCs. Herein, we review the current research on the role of the Hh signaling pathway in mediating the behavior of GSCs. In addition, some suggestions for future research are proposed.

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