Selective, Temporary Postoperative Inhibition of Lymphangiogenesis by Integrin α5β1 Blockade Improves Allograft Survival in a Murine Model of High-Risk Corneal Transplantation.

Corneal inflammatory hem- and lymphangiogenesis significantly increase the risk for immune rejection after subsequent allogeneic corneal transplantation. The purpose of this study was to analyze the impact of temporary selective inhibition of lymphangiogenesis after transplantation on graft survival. Allogeneic transplantation from C57BL/6 mice to BalbC mice was performed as "high-risk" keratoplasty in a prevascularized corneal host bed (suture-induced inflammatory corneal neovascularization).

The growing research toolbox for SLC13A5 citrate transporter disorder: a rare disease with animal models, cell lines, an ongoing Natural History Study and an engaged patient advocacy organization.

TESS Research Foundation (TESS) is a patient-led nonprofit organization seeking to understand the basic biology and clinical impact of pathogenic variants in the SLC13A5 gene. TESS aims to improve the fundamental understanding of citrate's role in the brain, and ultimately identify treatments and cures for the associated disease. TESS identifies, organizes, and develops collaboration between researchers, patients, clinicians, and the pharmaceutical industry to improve the lives of those suffering from SLC13A5 citrate transport disorder.

Expression of the plasma membrane citrate carrier (pmCiC) in human cancerous tissues-correlation with tumour aggressiveness.

We have recently shown that cancer cells of various origins take up extracellular citrate through the plasma membrane citrate carrier (pmCiC), a specific plasma membrane citrate transporter. Extracellular citrate is required to support cancer cell metabolism, in particular fatty acid synthesis, mitochondrial activity, protein synthesis and histone acetylation. In addition, cancer cells tend to acquire a metastatic phenotype in the presence of extracellular citrate.

Targeting Longevity Gene : A Novel Approach to Prevent Age-Related Bone Fragility and Osteoporosis.

Reduced expression of the plasma membrane citrate transporter , also known as INDY, has been linked to increased longevity and mitigated age-related cardiovascular and metabolic diseases. Citrate, a vital component of the tricarboxylic acid cycle, constitutes 1-5% of bone weight, binding to mineral apatite surfaces. Our previous research highlighted osteoblasts' specialized metabolic pathway facilitated by regulating citrate uptake, production, and deposition within bones.

The citrate transporter SLC13A5 as a therapeutic target for kidney disease: evidence from Mendelian randomization to inform drug development.

Background: Solute carrier family 13 member 5 (SLC13A5) is a Na-coupled citrate co-transporter that mediates entry of extracellular citrate into the cytosol. SLC13A5 inhibition has been proposed as a target for reducing progression of kidney disease. The aim of this study was to leverage the Mendelian randomization paradigm to gain insight into the effects of SLC13A5 inhibition in humans, towards prioritizing and informing clinical development efforts.

The dual role of citrate in cancer.

Citrate is a key metabolite of the Krebs cycle that can also be exported in the cytosol, where it performs several functions. In normal cells, citrate sustains protein acetylation, lipid synthesis, gluconeogenesis, insulin secretion, bone tissues formation, spermatozoid mobility, and immune response. Dysregulation of citrate metabolism is implicated in several pathologies, including cancer.

A Novel and Cross-Species Active Mammalian INDY (NaCT) Inhibitor Ameliorates Hepatic Steatosis in Mice with Diet-Induced Obesity.

Mammalian INDY (mINDY, NaCT, gene symbol ) is a potential target for the treatment of metabolically associated fatty liver disease (MAFLD). This study evaluated the effects of a selective, cross-species active, non-competitive, non-substrate-like inhibitor of NaCT. First, the small molecule inhibitor ETG-5773 was evaluated for citrate and succinate uptake and fatty acid synthesis in cell lines expressing both human NaCT and mouse Nact.

Extracellular citrate and metabolic adaptations of cancer cells.

It is well established that cancer cells acquire energy via the Warburg effect and oxidative phosphorylation. Citrate is considered to play a crucial role in cancer metabolism by virtue of its production in the reverse Krebs cycle from glutamine. Here, we review the evidence that extracellular citrate is one of the key metabolites of the metabolic pathways present in cancer cells.

The longevity gene INDY (I'm Not Dead Yet) in metabolic control: Potential as pharmacological target.

The regulation of metabolic processes by the Indy (I'm Not Dead Yet) (SLC13A5/NaCT) gene was revealed through studies in Drosophila melanogaster and Caenorhabditis elegans. Reducing the expression of Indy in these species extended their life span by a mechanism resembling caloric restriction, without reducing food intake. In D.

Integrin α5β1 Inhibition by CLT-28643 Reduces Postoperative Wound Healing in a Mouse Model of Glaucoma Filtration Surgery.

Purpose: To evaluate the therapeutic potential of the small molecule integrin α5β1 inhibitor, CLT-28643, to improve the filtering surgery outcome in a mouse model. Different dose regimens and administration routes of the inhibitor were compared with mitomycin C (MMC), the gold standard in clin ical practice.

Methods: The efficacy of CLT-28643 on surgical outcome was studied in a mouse model for filtering surgery (n = 40 eyes from 20 mice per group).

Subchoroidal Release of VEGF and bFGF Produces Choroidal Neovascularization in Rabbit.

Purpose: Intravitreal vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) produced florid retinal neovascularization and hemorrhage in the rabbit. This study seeks to determine whether sustained subchoroidal release of both VEGF and bFGF can induce robust choroidal neovascularization (CNV) in the rabbit.

Methods: Subchoroidal implantation through the sclera of polymeric pellets containing both 15 μg VEGF and 15 μg bFGF was performed on adult pigmented male Dutch belted rabbits (N = 6) and NZW albinos (N = 8).

α5β1-Integrin inhibitor (CLT-28643) effective in rabbit trabeculectomy model.

Purpose: Glaucoma filtration surgery (GFS) fails due to fibrosis. The α5β1-integrin plays a pivotal role in fibrosis, angiogenesis and inflammation. This is the first experiment evaluating the prevention of fibrosis after GFS by a specific small molecule α5β1-integrin inhibitor (CLT-28643).

Inflammation-dependent alpha 5 beta 1 (very late antigen-5) expression on leukocytes reveals a functional role for this integrin in acute peritonitis.

The potential role of alpha 5 beta 1 (VLA-5) in leukocyte trafficking in zymosan-induced acute peritonitis was determined. In naïve mice, approximately 98% of Gr1(high) cells (PMN) in bone marrow and circulation were alpha 5 beta 1-negative; these profiles were modestly affected by peritoneal injection of zymosan. In contrast, approximately 30% of Gr1(high) cells recruited by zymosan (24 h) to the peritoneal cavity expressed alpha 5 beta 1.

Cutting edge: lymphatic vessels, not blood vessels, primarily mediate immune rejections after transplantation.

The purpose of this study was to determine the relative importance of blood vessels (hemangiogenesis) versus lymphatic vessels (lymphangiogenesis) in mediating immunological responses after transplantation. Using the murine model of corneal transplantation, graft survival was compared in differentially prevascularized and avascular recipient beds. Donor corneas (C57BL/6) were transplanted into uninflamed or inflamed avascular, prehemvascularized only or prehemvascularized and prelymphvascularized recipient murine eyes (BALB/C).

SAR of N-phenyl piperidine based oral integrin alpha5beta1 antagonists.

Recently, a new class of selective integrin alpha5beta1inhibitors consisting of a heterocyclic based scaffold was published. Herein the SAR and pharmacokinetic profiles of N-phenyl piperidine derivatives are described.

Discovery of orally available integrin alpha5beta1 antagonists.

Previous research within our laboratories identified the 3-hydroxypyrrolidine scaffold 1 as a new and selective integrin alpha5beta1 inhibitor class which was designed for local administration. Herein the discovery of new orally available integrin alpha5beta1 inhibitor scaffolds for potential systemic treatment is described.

Preclinical evaluation of the novel small-molecule integrin alpha5beta1 inhibitor JSM6427 in monkey and rabbit models of choroidal neovascularization.

Objective: To evaluate the pharmacologic activity and tolerability of JSM6427, a potent and first selective small-molecule inhibitor of integrin alpha5beta1, in monkey and rabbit models of choroidal neovascularization (CNV).

Methods: JSM6427 selectivity for alpha5beta1 was evaluated by in vitro binding assays while the ability of JSM6427 to inhibit CNV was investigated in a laser-induced monkey model and a growth factor-induced rabbit model. Intravitreal injections of JSM6427 (100, 300, or 1000 microg) or vehicle were administered immediately after the CNV induction procedure and at weekly intervals for 4 weeks.

Assessment of the integrin alpha5beta1 antagonist JSM6427 in proliferative vitreoretinopathy using in vitro assays and a rabbit model of retinal detachment.

Purpose: To explore the role of integrin alpha5beta1 in proliferative vitreoretinopathy (PVR) pathogenesis by evaluating the expression alpha5beta1 on ARPE-19 cells and patient proliferative membranes, quantifying the inhibitory effects of JSM6427 (a small molecule alpha5beta1 inhibitor) on ARPE-19 cell adhesion and migration, and assessing the therapeutic potential of JSM6427 in a rabbit retinal detachment model.

Methods: Expression of alpha5beta1 was evaluated on activated ARPE-19 cells by flow cytometry and on PVR membranes by immunohistochemistry. ARPE-19 cells were used in fibronectin-dependent adhesion and migration assays with various concentrations of JSM6427; IC(50) was calculated.

Mapping the ligand-binding pocket of integrin alpha5beta1 using a gain-of-function approach.

Integrin alpha5beta1 is a key receptor for the extracellular matrix protein fibronectin. Antagonists of human integrin alpha5beta1 have therapeutic potential as anti-angiogenic agents in cancer and diseases of the eye. However, the structure of the integrin is unsolved and the atomic basis of fibronectin and antagonist binding by integrin alpha5beta1 is poorly understood.

Integrin alpha5beta1 mediates attachment, migration, and proliferation in human retinal pigment epithelium: relevance for proliferative retinal disease.

Purpose: The aim of this study was to determine the expression and localization of integrin alpha5beta1 in human retinal pigment epithelium (RPE) and its ability to modulate RPE cell attachment, proliferation, migration, and F-actin cytoskeleton distribution.

Methods: Expression and localization of alpha5beta1 were analyzed on human RPE by immunoblot/immunofluorescence. Polarized secretion of fibronectin was measured.

alpha5beta1 Integrin blockade inhibits lymphangiogenesis in airway inflammation.

The integrin alpha5beta1 has been previously implicated in tumor angiogenesis, but its role in the remodeling of both blood vessels and lymphatics during inflammation is at an early stage of understanding. We examined this issue using a selective, small-molecule inhibitor of alpha5beta1 integrin, 2-aroylamino-3-{4-[(pyridin-2-ylaminomethyl)heterocyclyl]phenyl}propionic acid (JSM8757), in a model of sustained airway inflammation in mice with Mycoplasma pulmonis infection, which is known to be accompanied by robust blood vessel remodeling and lymphangiogenesis. The inhibitor significantly decreased the proliferation of lymphatic endothelial cells in culture and the number of lymphatic sprouts and new lymphatics in airways of mice infected for 2 weeks but did not reduce remodeling of blood vessels in the same airways.

Breaking the dogma of the metal-coordinating carboxylate group in integrin ligands: introducing hydroxamic acids to the MIDAS to tune potency and selectivity.

A suitable substitute: All integrin receptors bind their ligands, which contain an aspartate residue, in the metal-ion- dependent adhesion site (MIDAS). So far all attempts to replace the carboxyl group of aspartate with other, pharmacologically favorable isosteric groups have failed. Now it has been shown that a hydroxamic acid group can replace the carboxyl group; the resulting ligand retains its high binding activity.

An alpha5beta1 integrin inhibitor attenuates glioma growth.

Integrins are heterodimeric transmembrane proteins, which mediate cell-cell and cell-extracellular matrix (ECM) interaction. We show, that an inhibitor of alpha5 beta1 integrin (alpha5beta1), JSM6427, attenuated glioma growth and decreased the density of microglia at the tumor border. 21 days after glioma cell injection into an experimental mouse model, the tumor volume was significantly smaller after treating animals for 14 days with JSM6427 as compared to controls.