CXXC5 mediates growth plate senescence and is a target for enhancement of longitudinal bone growth

Abstract

Longitudinal bone growth ceases with growth plate senescence during puberty. However, the molecular mechanisms of this phenomenon are largely unexplored. Here, we examined Wnt-responsive genes before and after growth plate senescence and found that CXXC finger protein 5 (CXXC5), a negative regulator of the Wnt/β-catenin pathway, was gradually elevated with reduction of Wnt/β-catenin signaling during senescent changes of rodent growth plate. Cxxc5−/− mice demonstrated delayed growth plate senescence and tibial elongation. As CXXC5 functions by interacting with dishevelled (DVL), we sought to identify small molecules capable of disrupting this interaction. In vitro screening assay monitoring CXXC5–DVL interaction revealed that several indirubin analogs were effective antagonists of this interaction. A functionally improved indirubin derivative, KY19382, elongated tibial length through delayed senescence and further activation of the growth plate in adolescent mice. Collectively, our findings reveal an important role for CXXC5 as a suppressor of longitudinal bone growth involving growth plate activity.

Approaches for Regenerative Healing of Cutaneous Wound with an Emphasis on Strategies Activating the Wnt/β-Catenin Pathway

“…can be transcriptionally induced by the Wnt/bcatenin signaling itself or under a variety of pathophysiological states (e.g., alopecia, osteoporosis, wound formation, and termination of height growth at puberty), and these pathological aberrancies can be restored in CXXC5 knockout mice of the disease model systems. 13,80,124,125 Taken together, these findings indicate that CXXC5 can be a therapeutic target for diseases caused by suppression of Wnt/b-catenin signaling. The importance of targeting cytosolic CXXC5 function in wound healing was supported by enhanced cutaneous wound healing in mice treated with the protein transduction domain-fused DVLbinding motif (PTD-DBM) peptide, which blocks CXXC5-DVL protein-protein interactions (PPI).…”

KY19382, a novel activator of Wnt/β‐catenin signalling, promotes hair regrowth and hair follicle neogenesis

“…KY19382 (5, 6-dichloroindirubin-3 0 -methoxime) was synthesized in our laboratory (Choi, Kim et al, 2019). Minoxidil was supplied by Tokyo Chemical Industry Co. (Tokyo, Japan) and 2,2,2-tribromoethanol by Sigma Aldrich (St. Louis, MO, USA).…”

“…A rat vibrissa immortalized DP cell line was donated by the Skin Research Institute of the Amore Pacific Corporation R&D Center (Yongin, Korea). HEK293 Wnt/β-catenin signalling reporter cell (HEK293 cells [ATCC Cat# CRL-1573, RRID:CVCL_0045] containing a chromosomally integrated TOPflash reporter) is described in our previous study (Choi et al, 2019). Rat DP or HEK293 reporter cells were cultured in DMEM (Gibco, Gaithersburg, USA) containing 10% (v/v) FBS (Gibco, Gaithersburg, USA) and 100-UÁm À1 penicillin/streptomycin (Gibco, Gaithersburg, USA) at 37 C in a humidified atmosphere of 5% CO 2 .…”

“…I3O is known to be a Wnt/β‐catenin activator that stabilizes β‐catenin via inhibition of GSK‐3β and has been shown to accelerate bone growth and inhibit adipogenesis (Cha & Choi, 2014; Choi et al, 2014; Zahoor et al, 2014). Furthermore, we recently found that KY19382 elongated tibial length by inactivating GSK‐3β and blocking the binding of CXXC‐type zinc finger protein 5 (CXXC5) and dishevelled (Dvl) (Choi et al, 2019). Moreover, PTD‐DBM, a peptide that interferes with CXXC5–Dvl interaction via binding to the PDZ domain of Dvl, stimulated wound‐induced hair follicle neogenesis (WIHN) and hair regrowth (Lee et al, 2017).…”

A Mixed Micellar Formulation for the Transdermal Delivery of an Indirubin Analog

“…KY19382, 5, 6-dichloroindirubin-3′-methoxime ( Figure 1a), was synthesized and supplied by Dr. G.H. Han (Yonsei University, Seoul, Korea) [19]. (2-hydroxyproply)-β-cyclodextrin (HP-β-CD), Kolliphor® EL (Polyoxyl castor oil, pH range 6.0-8.0), Tween 20, Tween 80, and polyethylene glycol (PEG) 400 were purchased from Sigma Aldrich (St. Louis, MO, USA).…”