Over-expression of thymosin beta4 promotes abnormal tooth development and stimulation of hair growth

Abstract

Thymosin β β β β β4 has multi-functional roles in cell physiology. It accelerates wound healing, hair growth and angiogenesis, and increases laminin-5 expression in corneal epithelium. Furthermore, thymosin β β β β β4 stimulates tumor growth and metastasis by induction of cell migration and vascular endothelial growth factor-mediated angiogenesis. Using a construct on the skinspecific keratin-5 promoter, we have developed thymosin β β β β β4 over-expressing transgenic mice to further study its functional roles. Thymosin β β β β β4 in adult skin and in embryonic stages of the transgenic mouse was analyzed by both Western blot and immunohistochemistry. The overexpression of thymosin β β β β β4 was observed especially around hair follicles and in the teeth in the transgenic mice. We examined the phenotype of the thymosin β β β β β4 over-expressing mice. Hair growth was accelerated. In addition, the transgenic mice had abnormally-shaped white teeth and dull incisors. We found that the expression of laminin-5 was up-regulated in the skin of the transgenic mice. We conclude that thymosin β β β β β4 has an important physiological role in hair growth and in tooth development.

The Role of Thymosin Beta 4 on Odontogenic Differentiation in Human Dental Pulp Cells

“…In addition, gene expression of DSPP, BSP, OCN, ON, and collagen type I related to mineralization is significantly decreased when Tβ4 is inhibited in the odontoblast-like cells MDPC-23 by Tβ4 siRNA [13]. Moreover, we recently reported that Tβ4-overexpressing transgenic mice promote abnormal hair growth and tooth development as observed by abnormally shaped white teeth and dull incisors [14]. Although Tβ4 peptide accelerates bone regeneration and osteogenesis of tooth extraction sockets [15], the underlying molecular mechanisms for controlling odontoblastic growth and differentiation by Tβ4 are still not fully understood in regenerative dentistry.…”

Expression of thymosin beta-4 in human periodontal ligament cells and mouse periodontal tissue and its role in osteoblastic/cementoblastic differentiation

“…Tβ4 mediates differentiation of endothelial cells (Malinda et al, 1997), keratinocytes (Philp et al, 2004b), and oligodendrocytes (Santra et al, 2012). We previously reported that Tβ4-overexpressing transgenic mice have abnormal tooth development and enhanced stimulation of hair growth (Cha et al, 2010).…”

The regulatory role of the tetrapeptide AcSDKP in skin and hair physiology and the prevention of ageing effects in these tissues – a potential cosmetic role

“…Ongoing research demonstrates the powerful effect of Tb4 on ageing skin, in part because of its ability to stimulate the production of collagen and elastin [71]. Moreover, the well-documented ability of Tb4 to enhance hair growth stay in line with the reported properties of AcSDKP [72,73].…”