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Sun K, Li X, Scherer PE. Extracellular Matrix (ECM) and Fibrosis in Adipose Tissue: Overview and Perspectives. Compr Physiol 2023; 13:4387-4407. [PMID: 36715281 PMCID: PMC9957663 DOI: 10.1002/cphy.c220020] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Fibrosis in adipose tissue is a major driver of obesity-related metabolic dysregulation. It is characterized by an overaccumulation of extracellular matrix (ECM) during unhealthy expansion of adipose tissue in response to over nutrition. In obese adipose-depots, hypoxia stimulates multiple pro-fibrotic signaling pathways in different cell populations, thereby inducing the overproduction of the ECM components, including collagens, noncollagenous proteins, and additional enzymatic components of ECM synthesis. As a consequence, local fibrosis develops. The result of fibrosis-induced mechanical stress not only triggers cell necrosis and inflammation locally in adipose tissue but also leads to system-wide lipotoxicity and insulin resistance. A better understanding of the mechanisms underlying the obesity-induced fibrosis will help design therapeutic approaches to reduce or reverse the pathological changes associated with obese adipose tissue. Here, we aim to summarize the major advances in the field, which include newly identified fibrotic factors, cell populations that contribute to the fibrosis in adipose tissue, as well as novel mechanisms underlying the development of fibrosis. We further discuss the potential therapeutic strategies to target fibrosis in adipose tissue for the treatment of obesity-linked metabolic diseases and cancer. © 2023 American Physiological Society. Compr Physiol 13:4387-4407, 2023.
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Affiliation(s)
- Kai Sun
- Center for Metabolic and Degenerative Diseases, Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Xin Li
- Center for Metabolic and Degenerative Diseases, Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Philipp E. Scherer
- Department of Internal Medicine, Touchstone Diabetes Center, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
- Department of Cell Biology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
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2
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Volkova YL, Pickel C, Jucht AE, Wenger RH, Scholz CC. The Asparagine Hydroxylase FIH: A Unique Oxygen Sensor. Antioxid Redox Signal 2022; 37:913-935. [PMID: 35166119 DOI: 10.1089/ars.2022.0003] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Significance: Limited oxygen availability (hypoxia) commonly occurs in a range of physiological and pathophysiological conditions, including embryonic development, physical exercise, inflammation, and ischemia. It is thus vital for cells and tissues to monitor their local oxygen availability to be able to adjust in case the oxygen supply is decreased. The cellular oxygen sensor factor inhibiting hypoxia-inducible factor (FIH) is the only known asparagine hydroxylase with hypoxia sensitivity. FIH uniquely combines oxygen and peroxide sensitivity, serving as an oxygen and oxidant sensor. Recent Advances: FIH was first discovered in the hypoxia-inducible factor (HIF) pathway as a modulator of HIF transactivation activity. Several other FIH substrates have now been identified outside the HIF pathway. Moreover, FIH enzymatic activity is highly promiscuous and not limited to asparagine hydroxylation. This includes the FIH-mediated catalysis of an oxygen-dependent stable (likely covalent) bond formation between FIH and selected substrate proteins (called oxomers [oxygen-dependent stable protein oligomers]). Critical Issues: The (patho-)physiological function of FIH is only beginning to be understood and appears to be complex. Selective pharmacologic inhibition of FIH over other oxygen sensors is possible, opening new avenues for therapeutic targeting of hypoxia-associated diseases, increasing the interest in its (patho-)physiological relevance. Future Directions: The contribution of FIH enzymatic activity to disease development and progression should be analyzed in more detail, including the assessment of underlying molecular mechanisms and relevant FIH substrate proteins. Also, the molecular mechanism(s) involved in the physiological functions of FIH remain(s) to be determined. Furthermore, the therapeutic potential of recently developed FIH-selective pharmacologic inhibitors will need detailed assessment. Antioxid. Redox Signal. 37, 913-935.
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Affiliation(s)
- Yulia L Volkova
- Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Christina Pickel
- Institute of Physiology, University of Zurich, Zurich, Switzerland
| | | | - Roland H Wenger
- Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Carsten C Scholz
- Institute of Physiology, University of Zurich, Zurich, Switzerland
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3
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Kaplan N, Liu M, Wang J, Yang W, Fiolek E, Peng H, Lavker RM. Eph signaling is regulated by miRNA-210: Implications for corneal epithelial repair. FASEB J 2022; 36:e22076. [PMID: 34856019 PMCID: PMC8647904 DOI: 10.1096/fj.202101423r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/25/2021] [Accepted: 11/17/2021] [Indexed: 01/03/2023]
Abstract
A distinct boundary exists between the progenitor cells in the basal limbal epithelium and the more differentiated corneal epithelial basal cells. We have shown that reciprocal expression patterns of EphA2 and Ephrin-A1 are likely to contribute to normal limbal-corneal epithelial compartmentalization as well as play a role in response to injury. How this signaling axis is regulated remains unclear. We have demonstrated that microRNAs (miRNAs) play critical roles in corneal epithelial wound healing and several miRNAs (e.g. miR-210) have been predicted to target ephrins. Previous expression profiling experiments demonstrated that miR-210 is prominently expressed in corneal epithelial cells. RNA-seq data acquired from miR-210-depleted HCECs showed up-regulation of genes involved in cellular migration. In addition, miR-210 is decreased after corneal injury while EphA2 is increased. Moreover, antago-210-treated HCECs markedly enhanced wound closure in a scratch wound assay. Antago-210 treatment resulted in increased EphA2 protein levels as well as pS897-EphA2, the pro-migratory form of EphA2. As expected, Ephrin-A1 levels were reduced, while levels of a well-known target of miR-210, Ephrin-A3, were increased by antago-210 treatment. The increase in migration with antago-210 could be inhibited by Ephrin-A1 overexpression, Ephrin-A1-Fc treatment or siRNA depletion of EphA2. However, depletion of Ephrin-A3 did not have effects on the antago-210-induced increase in migration. In addition, Ephrin-A1 overexpression and siEphA2 dampened EGFR signaling, which is increased by antago-210. Our data clearly demonstrate a link between miR-210 and EphA2/Ephrin-A1 signaling that regulates, in part, corneal epithelial migration. This interaction might potentially control the limbal-corneal epithelial boundary.
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Affiliation(s)
- Nihal Kaplan
- Department of Dermatology, Northwestern University, Chicago, IL, 60611, USA
| | - Min Liu
- Department of Dermatology, Northwestern University, Chicago, IL, 60611, USA
| | - Junyi Wang
- Department of Dermatology, Northwestern University, Chicago, IL, 60611, USA,Department of Ophthalmology, Ophthalmology and Visual Science Key Lab of PLA, Chinese PLA General Hospital, Beijing, China
| | - Wending Yang
- Department of Dermatology, Northwestern University, Chicago, IL, 60611, USA
| | - Elaina Fiolek
- Department of Dermatology, Northwestern University, Chicago, IL, 60611, USA
| | - Han Peng
- Department of Dermatology, Northwestern University, Chicago, IL, 60611, USA,Correspondence: Robert M. Lavker, Ph.D., Department of Dermatology, Northwestern University, 303 East Chicago Avenue, Ward 9-124, Chicago, IL 60611, USA;
| | - Robert M. Lavker
- Department of Dermatology, Northwestern University, Chicago, IL, 60611, USA,Correspondence: Han Peng, Ph.D., Department of Dermatology, Northwestern University, 303 East Chicago Avenue, Ward 9-120, Chicago, IL 60611, USA;
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4
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Abdelftah Z, Gaber AR, Abo-Eleneen RE, EL-Bakry AM. Microstructure characteristics of cornea of some birds: a comparative study. BENI-SUEF UNIVERSITY JOURNAL OF BASIC AND APPLIED SCIENCES 2021. [DOI: 10.1186/s43088-021-00155-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Light is the critical factor that affects the eye's morphology and auxiliary plans. The ecomorphological engineering of the cornea aids the physiological activities of the cornea during connections between photoreceptor neurons and light photons. Cornea was dissected free from the orbit from three avian species as ibis (Eudocium albus), duck (Anas platyrhynchus domesticus) and hawk (Buteo Buteo) and prepared for light and scanning electron microscopy and special stain for structural comparison related to function.
Results
The three investigated avian species are composed of three identical layers; epithelium, stroma, and endothelium, and two basement membranes; bowman's and Descemet’s membrane, separating two cellular layers, except for B. buteo which only has a Descemet’s membrane. The corneal layers in the investigated species display different affinity to stain with Periodic Acid Schiff stain. The external corneal surface secured by different normal epithelial cells ran from hexagonal to regular polygonal cells. Those epithelial cells are punctured by different diameter microholes and microplicae and microvilli of various length. Blebs are scarcely distributed over their surface. The present investigation utilized histological, histochemical and SEM examination.
Conclusions
The study presents a brief image/account of certain structures of cornea for three of Avian’s species. Data distinguish the anatomic structures of the owl's eye. The discussion explains the role of some functional anatomical structures all through the vision.
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5
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Grading criteria of histopathological evaluation in BCOP assay by various staining methods. Toxicol Res 2021; 38:9-17. [PMID: 35070936 PMCID: PMC8748586 DOI: 10.1007/s43188-021-00099-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 04/30/2021] [Accepted: 05/15/2021] [Indexed: 01/03/2023] Open
Abstract
This study was performed to provide information on classifying eye irritating chemicals using the BCOP assay. After the BCOP assay, bovine corneas were classified by IVIS presented in OECD test guideline 437, and three special staining methods (H&E, MT, and PAS) were performed for histopathological evaluation. Non-irritant chemicals (IVIS ≤ 3), showed intact structures. In the 3 < IVIS ≤ 55 group, epithelial cell edema was observed by H&E staining, and loose collagen bundles were confirmed by MT staining. In PAS staining, bleaching of the epithelium and reduced visibility of the basement membrane were observed. Severe irritant chemicals (IVIS > 55) showed large increases edema and nuclear condensation by H&E staining. Loose collagen bundles and vacuoles around keratocytes were also observed by MT staining. Bleaching of the epithelial layer, reduction in visibility, and thickness of the basement membrane were confirmed by PAS staining. Based on the stepwise histopathological analysis, we set the criteria and grades for histopathological evaluation and found that eye irritation was increased following the irritation degree of test chemicals. Further histopathological study will support and lead to improvements in the BCOP assay.
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Kaplan N, Wang S, Wang J, Yang W, Ventrella R, Majekodunmi A, Perez White BE, Getsios S, Mitchell BJ, Peng H, Lavker RM. Ciliogenesis and autophagy are coordinately regulated by EphA2 in the cornea to maintain proper epithelial architecture. Ocul Surf 2021; 21:193-205. [PMID: 34119713 DOI: 10.1016/j.jtos.2021.06.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 06/04/2021] [Accepted: 06/07/2021] [Indexed: 11/25/2022]
Abstract
PURPOSE To understand the relationship between ciliogenesis and autophagy in the corneal epithelium. METHODS siRNAs for EphA2 or PLD1 were used to inhibit protein expression in vitro. Morpholino-anti-EphA2 was used to knockdown EphA2 in Xenopus skin. An EphA2 knockout mouse was used to conduct loss of function studies. Autophagic vacuoles were visualized by contrast light microscopy. Autophagy flux, was measured by LC3 turnover and p62 protein levels. Immunostaining and confocal microscopy were conducted to visualize cilia in cultured cells and in vivo. RESULTS Loss of EphA2 (i) increased corneal epithelial thickness by elevating proliferative potential in wing cells, (ii) reduced the number of ciliated cells, (iii) increased large hollow vacuoles, that could be rescued by BafA1; (iv) inhibited autophagy flux and (v) increased GFP-LC3 puncta in the mouse corneal epithelium. This indicated a role for EphA2 in stratified epithelial assembly via regulation of proliferation as well as a positive role in both ciliogenesis and end-stage autophagy. Inhibition of PLD1, an EphA2 interacting protein that is a critical regulator of end-stage autophagy, reversed the accumulation of vacuoles, and the reduction in the number of ciliated cells due to EphA2 depletion, suggesting EphA2 regulation of both end-stage autophagy and ciliogenesis via PLD1. PLD1 mediated rescue of ciliogenesis by EphA2 depletion was blocked by BafA1, placing autophagy between EphA2 signaling and regulation of ciliogenesis. CONCLUSION Our findings demonstrate a novel role for EphA2 in regulating both autophagy and ciliogenesis, processes that are essential for proper corneal epithelial homeostasis.
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Affiliation(s)
- Nihal Kaplan
- Department of Dermatology, Northwestern University, Chicago, IL, 60611, USA
| | - Sijia Wang
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Junyi Wang
- Department of Dermatology, Northwestern University, Chicago, IL, 60611, USA; Department of Ophthalmology, The Third Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Wending Yang
- Department of Dermatology, Northwestern University, Chicago, IL, 60611, USA
| | - Rosa Ventrella
- Cell and Developmental Biology, Northwestern University, Chicago, IL 60611, USA
| | - Ahmed Majekodunmi
- Department of Neurology, Northwestern University, Chicago, IL, 60611, USA
| | | | | | - Brian J Mitchell
- Cell and Developmental Biology, Northwestern University, Chicago, IL 60611, USA
| | - Han Peng
- Department of Dermatology, Northwestern University, Chicago, IL, 60611, USA.
| | - Robert M Lavker
- Department of Dermatology, Northwestern University, Chicago, IL, 60611, USA.
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7
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Su Z, Wang J, Lai Q, Zhao H, Hou L. KIT ligand produced by limbal niche cells under control of SOX10 maintains limbal epithelial stem cell survival by activating the KIT/AKT signalling pathway. J Cell Mol Med 2020; 24:12020-12031. [PMID: 32914934 PMCID: PMC7579694 DOI: 10.1111/jcmm.15830] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 05/03/2020] [Accepted: 08/17/2020] [Indexed: 12/26/2022] Open
Abstract
Homeostasis and function of limbal epithelial stem cells (LESCs) rely on the limbal niche, which, if dysfunctional, leads to limbal epithelial stem cell deficiency (LSCD) and impaired vision. Hence, recovery of niche function is a principal therapeutic goal in LSCD, but the molecular mechanisms of limbal niche homeostasis are still largely unknown. Here, we report that the neural crest transcription factor SOX10, which is expressed in neural crest‐derived limbal niche cells (LNCs), is required for LNCs to promote survival of LESCs both in vivo and in vitro. In fact, using mice with a Sox10 mutation and in vitro coculture experiments, we show that SOX10 in LNCs stimulates the production of KIT ligand (KITL), which in turn activates in LESCs the KIT‐AKT signalling pathway that protects the cells against activated CASPASE 3‐associated cell death. These results suggest that SOX10 and the KITL/KIT‐AKT pathway play key roles in limbal niche homeostasis and LESC survival. These findings provide molecular insights into limbal niche function and may point to rational approaches for therapeutic interventions in LSCD.
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Affiliation(s)
- Zhongyuan Su
- Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, China.,State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou, China
| | - Jing Wang
- Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, China.,State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou, China
| | - Qinghua Lai
- Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, China
| | - Huanyu Zhao
- Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, China
| | - Ling Hou
- Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, China.,State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou, China
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8
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Lavker RM, Kaplan N, Wang J, Peng H. Corneal epithelial biology: Lessons stemming from old to new. Exp Eye Res 2020; 198:108094. [PMID: 32697979 DOI: 10.1016/j.exer.2020.108094] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 05/27/2020] [Accepted: 05/29/2020] [Indexed: 12/13/2022]
Abstract
The anterior surface of the eye functions as a barrier to the external environment and protects the delicate underlying tissues from injury. Central to this protection are the corneal, limbal and conjunctival epithelia. The corneal epithelium is a self-renewing stratified squamous epithelium that protects the underlying delicate structures of the eye, supports a tear film and maintains transparency so that light can be transmitted to the interior of the eye (Basu et al., 2014; Cotsarelis et al., 1989; Funderburgh et al., 2016; Lehrer et al., 1998; Pajoohesh-Ganji and Stepp, 2005; Parfitt et al., 2015; Peng et al., 2012b; Stepp and Zieske, 2005). In this review, dedicated to James Funderburgh and his contributions to visual science, in particular the limbal niche, corneal stroma and corneal stromal stem cells, we will focus on recent data on the identification of novel regulators in corneal epithelial cell biology, their roles in stem cell homeostasis, wound healing, limbal/corneal boundary maintenance and the utility of single cell RNA sequencing (scRNA-seq) in vision biology studies.
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Affiliation(s)
- Robert M Lavker
- Departments of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
| | - Nihal Kaplan
- Departments of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Junyi Wang
- Departments of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Department of Ophthalmology, The First Center of the PLA General Hospital, Haidian District, Beijing, China
| | - Han Peng
- Departments of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
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Kaplan N, Dong Y, Wang S, Yang W, Park JK, Wang J, Fiolek E, Perez White B, Chandel NS, Peng H, Lavker RM. FIH-1 engages novel binding partners to positively influence epithelial proliferation via p63. FASEB J 2019; 34:525-539. [PMID: 31914679 DOI: 10.1096/fj.201901512r] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 10/07/2019] [Accepted: 10/15/2019] [Indexed: 12/19/2022]
Abstract
Whereas much is known about the genes regulated by ΔNp63α in keratinocytes, how ΔNp63α is regulated is less clear. During studies with the hydroxylase, factor inhibiting hypoxia-inducible factor 1 (FIH-1), we observed increases in epidermal ΔNp63α expression along with proliferative capacity in a conditional FIH-1 transgenic mouse. Conversely, loss of FIH-1 in vivo and in vitro attenuated ΔNp63α expression. To elucidate the FIH-1/p63 relationship, BioID proteomics assays identified FIH-1 binding partners that had the potential to regulate p63 expression. FIH-1 interacts with two previously unknown partners, Plectin1 and signal transducer and activator of transcription 1 (STAT1) leading to the regulation of ΔNp63α expression. Two known interactors of FIH-1, apoptosis-stimulating of P53 protein 2 (ASPP2) and histone deacetylase 1 (HDAC1), were also identified. Knockdown of ASPP2 upregulated ΔNp63α and reversed the decrease in ΔNp63α by FIH-1 depletion. Additionally, FIH-1 regulates growth arrest and DNA damage-45 alpha (GADD45α), a negative regulator of ΔNp63α by interacting with HDAC1. GADD45α knockdown rescued reduction in ΔNp63α by FIH-1 depletion. Collectively, our data reveal that FIH-1 positively regulates ΔNp63α in keratinocytes via variety of signaling partners: (a) Plectin1/STAT1, (b) ASPP2, and (c) HDAC1/GADD45α signaling pathways.
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Affiliation(s)
- Nihal Kaplan
- Department of Dermatology, Northwestern University, Chicago, IL, USA
| | - Ying Dong
- Department of Dermatology, Northwestern University, Chicago, IL, USA.,Department of Ophthalmology, The First Affiliated Hospital, Chinese PLA General Hospital, Beijing, China
| | - Sijia Wang
- Department of Dermatology, Northwestern University, Chicago, IL, USA.,Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Wending Yang
- Department of Dermatology, Northwestern University, Chicago, IL, USA
| | - Jong Kook Park
- Department of Dermatology, Northwestern University, Chicago, IL, USA.,Department of Biomedical Science, College of Natural Sciences #8403, Hallym University, Chuncheon, Republic of Korea
| | - Junyi Wang
- Department of Dermatology, Northwestern University, Chicago, IL, USA.,Department of Ophthalmology, The First Affiliated Hospital, Chinese PLA General Hospital, Beijing, China
| | - Elaina Fiolek
- Department of Dermatology, Northwestern University, Chicago, IL, USA
| | | | | | - Han Peng
- Department of Dermatology, Northwestern University, Chicago, IL, USA
| | - Robert M Lavker
- Department of Dermatology, Northwestern University, Chicago, IL, USA
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Abstract
The cornea is a transparent outermost structure of the eye anterior segment comprising the highest density of innervated tissue. In the process of corneal innervation, trigeminal ganglion originated corneal nerves diligently traverse different corneal cell types in different corneal layers including the corneal stroma and epithelium. While crossing the stromal and epithelial cell layers during innervation, due to the existing physical contacts, close interactions occur between stromal keratocytes, epithelial cells, resident immune cells and corneal nerves. Furthermore, by producing various trophic and growth factors corneal cells assist in maintaining the growth and function of corneal nerves. Similarly, corneal nerve generated growth factors critically modify the corneal cell function in all the corneal layers. Due to their close association and contacts, on-going cross-communication between these cell types and corneal nerves play a vital role in the modulation of corneal nerve function, regeneration during wound healing. The present review highlights the influence of different corneal cell types and growth factors released from these cells on corneal nerve regeneration and function.
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Affiliation(s)
- Bhavani S Kowtharapu
- Department of Ophthalmology, Rostock University Medical Centre, Rostock, Germany
| | - Oliver Stachs
- Department of Ophthalmology, Rostock University Medical Centre, Rostock, Germany
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11
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Orang AV, Petersen J, McKinnon RA, Michael MZ. Micromanaging aerobic respiration and glycolysis in cancer cells. Mol Metab 2019; 23:98-126. [PMID: 30837197 PMCID: PMC6479761 DOI: 10.1016/j.molmet.2019.01.014] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 01/22/2019] [Accepted: 01/30/2019] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Cancer cells possess a common metabolic phenotype, rewiring their metabolic pathways from mitochondrial oxidative phosphorylation to aerobic glycolysis and anabolic circuits, to support the energetic and biosynthetic requirements of continuous proliferation and migration. While, over the past decade, molecular and cellular studies have clearly highlighted the association of oncogenes and tumor suppressors with cancer-associated glycolysis, more recent attention has focused on the role of microRNAs (miRNAs) in mediating this metabolic shift. Accumulating studies have connected aberrant expression of miRNAs with direct and indirect regulation of aerobic glycolysis and associated pathways. SCOPE OF REVIEW This review discusses the underlying mechanisms of metabolic reprogramming in cancer cells and provides arguments that the earlier paradigm of cancer glycolysis needs to be updated to a broader concept, which involves interconnecting biological pathways that include miRNA-mediated regulation of metabolism. For these reasons and in light of recent knowledge, we illustrate the relationships between metabolic pathways in cancer cells. We further summarize our current understanding of the interplay between miRNAs and these metabolic pathways. This review aims to highlight important metabolism-associated molecular components in the hunt for selective preventive and therapeutic treatments. MAJOR CONCLUSIONS Metabolism in cancer cells is influenced by driver mutations but is also regulated by posttranscriptional gene silencing. Understanding the nuanced regulation of gene expression in these cells and distinguishing rapid cellular responses from chronic adaptive mechanisms provides a basis for rational drug design and novel therapeutic strategies.
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Affiliation(s)
- Ayla V Orang
- Flinders Centre for Innovation in Cancer, Flinders University, Flinders Medical Centre, Adelaide, South Australia 5042, Australia.
| | - Janni Petersen
- Flinders Centre for Innovation in Cancer, Flinders University, Flinders Medical Centre, Adelaide, South Australia 5042, Australia.
| | - Ross A McKinnon
- Flinders Centre for Innovation in Cancer, Flinders University, Flinders Medical Centre, Adelaide, South Australia 5042, Australia.
| | - Michael Z Michael
- Flinders Centre for Innovation in Cancer, Flinders University, Flinders Medical Centre, Adelaide, South Australia 5042, Australia.
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12
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Nagosa S, Leesch F, Putin D, Bhattacharya S, Altshuler A, Serror L, Amitai-Lange A, Nasser W, Aberdam E, Rouleau M, Tattikota SG, Poy MN, Aberdam D, Shalom-Feuerstein R. microRNA-184 Induces a Commitment Switch to Epidermal Differentiation. Stem Cell Reports 2017; 9. [PMID: 29198823 PMCID: PMC5785777 DOI: 10.1016/j.stemcr.2017.10.030 10.13039/501100003977] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023] Open
Abstract
miR-184 is a highly evolutionary conserved microRNA (miRNA) from fly to human. The importance of miR-184 was underscored by the discovery that point mutations in miR-184 gene led to corneal/lens blinding disease. However, miR-184-related function in vivo remained unclear. Here, we report that the miR-184 knockout mouse model displayed increased p63 expression in line with epidermal hyperplasia, while forced expression of miR-184 by stem/progenitor cells enhanced the Notch pathway and induced epidermal hypoplasia. In line, miR-184 reduced clonogenicity and accelerated differentiation of human epidermal cells. We showed that by directly repressing cytokeratin 15 (K15) and FIH1, miR-184 induces Notch activation and epidermal differentiation. The disease-causing miR-184C57U mutant failed to repress K15 and FIH1 and to induce Notch activation, suggesting a loss-of-function mechanism. Altogether, we propose that, by targeting K15 and FIH1, miR-184 regulates the transition from proliferation to early differentiation, while mis-expression or mutation in miR-184 results in impaired homeostasis.
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Affiliation(s)
- Sara Nagosa
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Friederike Leesch
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Daria Putin
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Swarnabh Bhattacharya
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Anna Altshuler
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Laura Serror
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Aya Amitai-Lange
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Waseem Nasser
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Edith Aberdam
- University Paris Diderot, Sorbonne Paris Cité, Paris 75475, France; INSERM U976, Hôpital St-Louis, Paris 75010, France
| | - Matthieu Rouleau
- CNRS, LP2M, UMR7370, Faculté de Médecine, Nice, France; Université Nice Sophia Antipolis, Nice, France
| | - Sudhir G Tattikota
- Max Delbrueck Center for Molecular Medicine, Robert Roessle Strasse 10, Berlin 13125, Germany
| | - Matthew N Poy
- Max Delbrueck Center for Molecular Medicine, Robert Roessle Strasse 10, Berlin 13125, Germany
| | - Daniel Aberdam
- University Paris Diderot, Sorbonne Paris Cité, Paris 75475, France; INSERM U976, Hôpital St-Louis, Paris 75010, France
| | - Ruby Shalom-Feuerstein
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel.
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13
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Nagosa S, Leesch F, Putin D, Bhattacharya S, Altshuler A, Serror L, Amitai-Lange A, Nasser W, Aberdam E, Rouleau M, Tattikota SG, Poy MN, Aberdam D, Shalom-Feuerstein R. microRNA-184 Induces a Commitment Switch to Epidermal Differentiation. Stem Cell Reports 2017; 9:1991-2004. [PMID: 29198823 PMCID: PMC5785777 DOI: 10.1016/j.stemcr.2017.10.030] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 10/31/2017] [Accepted: 10/31/2017] [Indexed: 12/28/2022] Open
Abstract
miR-184 is a highly evolutionary conserved microRNA (miRNA) from fly to human. The importance of miR-184 was underscored by the discovery that point mutations in miR-184 gene led to corneal/lens blinding disease. However, miR-184-related function in vivo remained unclear. Here, we report that the miR-184 knockout mouse model displayed increased p63 expression in line with epidermal hyperplasia, while forced expression of miR-184 by stem/progenitor cells enhanced the Notch pathway and induced epidermal hypoplasia. In line, miR-184 reduced clonogenicity and accelerated differentiation of human epidermal cells. We showed that by directly repressing cytokeratin 15 (K15) and FIH1, miR-184 induces Notch activation and epidermal differentiation. The disease-causing miR-184C57U mutant failed to repress K15 and FIH1 and to induce Notch activation, suggesting a loss-of-function mechanism. Altogether, we propose that, by targeting K15 and FIH1, miR-184 regulates the transition from proliferation to early differentiation, while mis-expression or mutation in miR-184 results in impaired homeostasis.
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Affiliation(s)
- Sara Nagosa
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Friederike Leesch
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Daria Putin
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Swarnabh Bhattacharya
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Anna Altshuler
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Laura Serror
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Aya Amitai-Lange
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Waseem Nasser
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Edith Aberdam
- University Paris Diderot, Sorbonne Paris Cité, Paris 75475, France; INSERM U976, Hôpital St-Louis, Paris 75010, France
| | - Matthieu Rouleau
- CNRS, LP2M, UMR7370, Faculté de Médecine, Nice, France; Université Nice Sophia Antipolis, Nice, France
| | - Sudhir G Tattikota
- Max Delbrueck Center for Molecular Medicine, Robert Roessle Strasse 10, Berlin 13125, Germany
| | - Matthew N Poy
- Max Delbrueck Center for Molecular Medicine, Robert Roessle Strasse 10, Berlin 13125, Germany
| | - Daniel Aberdam
- University Paris Diderot, Sorbonne Paris Cité, Paris 75475, France; INSERM U976, Hôpital St-Louis, Paris 75010, France
| | - Ruby Shalom-Feuerstein
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel.
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14
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Park JK, Peng H, Yang W, Katsnelson J, Volpert O, Lavker RM. miR-184 exhibits angiostatic properties via regulation of Akt and VEGF signaling pathways. FASEB J 2017; 31:256-265. [PMID: 27825105 PMCID: PMC5161520 DOI: 10.1096/fj.201600746r] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/22/2016] [Indexed: 11/11/2022]
Abstract
Corneal avascularity is critical for achieving transparency necessary for proper transmission of light to the lens and visual acuity. Although much is known about angiogenesis and angiostasis, the precise regulation of these processes in the cornea is unclear. MicroRNA (miR)-184, the most abundant corneal epithelial miRNA, has been suggested to function in corneal angiostasis by altering VEGF signaling; however, the mechanism(s) underlying this regulation have not been addressed. Using a combination of in vitro and in vivo assays to evaluate angiogenesis, we demonstrated that human limbal epithelial keratinocytes (HLEKs) engineered to overexpress miR-184 secreted lower amounts of angiogenic mitogens. Human dermal microvascular cells exposed to conditioned medium from miR-184-overexpressing HLEKs were less proliferative and failed to seal linear scratch wounds. The in vivo Matrigel plug assay showed that conditioned medium from miR-184-expressing HLEKs elicited a lesser degree of neovascularization compared with controls. We found that miR-184 directly targets and represses the proangiogenic factors, friend of Gata 2 (FOG2), platelet-derived growth factor (PDGF)-β, and phosphatidic acid phosphatase 2b (PPAP2B). FOG2 regulates VEGF expression, whereas PDGF-β and PPAP2B regulate Akt activity. By attenuating both VEGF and Akt signaling, miR-184 acts as a broad-spectrum negative regulator of corneal angiogenesis.-Park, J. K., Peng, H., Yang, W., Katsnelson, J., Volpert, O., Lavker, R. M. miR-184 exhibits angiostatic properties via regulation of Akt and VEGF signaling pathways.
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Affiliation(s)
- Jong Kook Park
- Department of Dermatology Northwestern University, Chicago, Illinois, USA
| | - Han Peng
- Department of Dermatology Northwestern University, Chicago, Illinois, USA
| | - Wending Yang
- Department of Dermatology Northwestern University, Chicago, Illinois, USA
| | - Julia Katsnelson
- Department of Dermatology, New York Metropolitan Hospital, New York, New York, USA; and
| | - Olga Volpert
- Department of Urology, The Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Robert M Lavker
- Department of Dermatology Northwestern University, Chicago, Illinois, USA;
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15
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Stepp MA, Tadvalkar G, Hakh R, Pal-Ghosh S. Corneal epithelial cells function as surrogate Schwann cells for their sensory nerves. Glia 2016; 65:851-863. [PMID: 27878997 DOI: 10.1002/glia.23102] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 10/30/2016] [Accepted: 11/02/2016] [Indexed: 12/13/2022]
Abstract
The eye is innervated by neurons derived from both the central nervous system and peripheral nervous system (PNS). While much is known about retinal neurobiology and phototransduction, less attention has been paid to the innervation of the eye by the PNS and the roles it plays in maintaining a functioning visual system. The ophthalmic branch of the trigeminal ganglion contains somas of neurons that innervate the cornea. These nerves provide sensory functions for the cornea and are referred to as intraepithelial corneal nerves (ICNs) consisting of subbasal nerves and their associated intraepithelial nerve terminals. ICNs project for several millimeters within the corneal epithelium without Schwann cell support. Here, we present evidence for the hypothesis that corneal epithelial cells function as glial cells to support the ICNs. Much of the data supporting this hypothesis is derived from studies of corneal development and the reinnervation of the ICNs in the rodent and rabbit cornea after superficial wounds. Corneal epithelial cells activate in response to injury via mechanisms similar to those induced in Schwann cells during Wallerian Degeneration. Corneal epithelial cells phagocytize distal axon fragments within hours of ICN crush wounds. During aging, the proteins, lipids, and mitochondria within the ICNs become damaged in a process exacerbated by UV light. We propose that ICNs shed their aged and damaged termini and continuously elongate to maintain their density. Available evidence points to new unexpected roles for corneal epithelial cells functioning as surrogate Schwann cells for the ICNs during homeostasis and in response to injury. GLIA 2017;65:851-863.
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Affiliation(s)
- Mary Ann Stepp
- Department of Anatomy and Regenerative Biology, George Washington University Medical School, Washington, DC
| | - Gauri Tadvalkar
- Department of Anatomy and Regenerative Biology, George Washington University Medical School, Washington, DC
| | - Raymond Hakh
- Department of Anatomy and Regenerative Biology, George Washington University Medical School, Washington, DC
| | - Sonali Pal-Ghosh
- Department of Anatomy and Regenerative Biology, George Washington University Medical School, Washington, DC
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16
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Peng H, Kaplan N, Yang W, Getsios S, Lavker RM. FIH-1 disrupts an LRRK1/EGFR complex to positively regulate keratinocyte migration. THE AMERICAN JOURNAL OF PATHOLOGY 2014; 184:3262-71. [PMID: 25455687 DOI: 10.1016/j.ajpath.2014.08.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 07/07/2014] [Accepted: 08/07/2014] [Indexed: 12/29/2022]
Abstract
Factor inhibiting hypoxia-inducible factor 1 (FIH-1; official symbol HIF1AN) is a hydroxylase that negatively regulates hypoxia-inducible factor 1α but also targets other ankyrin repeat domain-containing proteins such as Notch receptor to limit epithelial differentiation. We show that FIH-1 null mutant mice exhibit delayed wound healing. Importantly, in vitro scratch wound assays demonstrate that the positive role of FIH-1 in migration is independent of Notch signaling, suggesting that this hydroxylase targets another ankyrin repeat domain-containing protein to positively regulate motogenic signaling pathways. Accordingly, FIH-1 increases epidermal growth factor receptor (EGFR) signaling, which in turn enhances keratinocyte migration via mitogen-activated protein kinase pathway, leading to extracellular signal-regulated kinase 1/2 activation. Our studies identify leucine-rich repeat kinase 1 (LRRK1), a key regulator of the EGFR endosomal trafficking and signaling, as an FIH-1 binding partner. Such an interaction prevents the formation of an EGFR/LRRK1 complex, necessary for proper EGFR turnover. The identification of LRRK1 as a novel target for FIH-1 provides new insight into how FIH-1 functions as a positive regulator of epithelial migration.
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Affiliation(s)
- Han Peng
- Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Nihal Kaplan
- Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Wending Yang
- Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Spiro Getsios
- Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Robert M Lavker
- Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
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17
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Calautti E. Akt modes of stem cell regulation: more than meets the eye? Discoveries (Craiova) 2013; 1:e8. [PMID: 32309540 PMCID: PMC6941558 DOI: 10.15190/d.2013.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Akt signaling regulates many cellular functions that are essential for the proper balance between self-renewal and differentiation of tissue-specific and embryonic stem cells (SCs). However, the roles of Akt and its downstream signaling in SC regulation are rather complex, as Akt activation can either promote SC self-renewal or depletion in a context-dependent manner. In this review we have evidenced three "modes" of Akt-dependent SC regulation, which can be exemplified by three different SC types. In particular, we will discuss: 1) the integration of Akt signaling within the "core" SC signaling circuitry in the maintenance of SC self-renewal and pluripotency (embryonic SCs); 2) quantitative changes in Akt signaling in SC metabolic activity and exit from quiescence (hematopoietic SCs); 3) qualitative changes of Akt signaling in SC regulation: signaling compartment-talization and isoform-specific functions of Akt proteins in SC self-renewal and differentiation (limbal-corneal keratinocyte SCs). These diverse modes of action are not to be intended as mutually exclusive. Rather, it is likely that Akt proteins participate with multiple parallel mechanisms to regulation of the same SC type. We propose that under specific circumstances dictated by distinct developmental stages, differentiation programs or tissue culture conditions, one mode of Akt action prevails over the others in determining SC fates.
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Affiliation(s)
- Enzo Calautti
- University of Turin, Department of Molecular Biotechnology and Health Sciences, Turin, Italy
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