Combination of melatonin and Wnt‐4 promotes neural cell differentiation in bovine amniotic epithelial cells and recovery from spinal cord injury

Abstract

Although melatonin has been shown to exhibit a wide variety of biological functions, its effects on promoting differentiation of neural cells remain unknown. Wnt signaling mediates major developmental processes during embryogenesis and regulates maintenance, self-renewal, and differentiation of adult mammalian stem cells. However, the role of the noncanonical Wnt pathway during neurogenesis remains poorly understood. In this study, the amniotic epithelial cells ( AECs) were isolated from bovine amnion and incubated with various melatonin concentrations (0.01, 0.1, 1, 10, or 100 μm) and 5 × 10(-5) m all-trans retinoic acid (RA) for screening optimum culture medium of neural differentiation, compared with each groups, 1 μm melatonin and 5 × 10(-5) m RA were selected to induce neural differentiation of AECs, and then siMT1, siMT2, oWnt-4, and siWnt-4 were expressed in AECs to research role of these genes in neural differentiation. Efficiency of neural differentiation was evaluated after expressed above genes using flow cytometry. Cell function of neural cells was demonstrated in vivo using spinal cord injury model after cell transplantation, and damage repair of spinal cord was assessed using cell tracking and Basso, Beattie, Bresnahan Locomotor Rating Scale scores. Results demonstrated that melatonin stimulated melatonin receptor 1, which subsequently increased bovine amniotic epithelial cell vitality and promoted differentiation into neural cells. This took place through cooperation with Wnt-4. Additionally, following cotreatment with melatonin and Wnt-4, neurogenesis gene expression was significantly altered. Furthermore, single inhibition of melatonin receptor 1 or Wnt-4 expression decreased expression of neurogenesis-related genes, and bovine amniotic epithelial cell-derived neural cells were successfully colonized into injured spinal cord, which suggested participation in tissue repair.

Wnt4‐modified NSC transplantation promotes functional recovery after spinal cord injury

“…31,32 In the current study, we reveal that Wnt4 has a strong capacity to induce neuronal differentiation (Figure 1). Canonical Wnt/β-catenin signaling is mediated by nuclear translocation of its central effector β-catenin.…”

“…Wnt4 is one of the non-canonical Wnt proteins that is believed to promote neuronal differentiation. 31,32 In the current study, we reveal that Wnt4 has a strong capacity to induce neuronal differentiation (Figure 1). Wnt family proteins are important for the modulation of neural differentiation and maintenance.…”

Melatonin ameliorates spinal cord injury by suppressing the activation of inflammasomes in rats

“…7 For example, MT acts as an efficient scavenger in the removal of hydrogen peroxide radicals, thus exerting a protective effect against neurological injuries, including traumatic brain injury and ischemic stroke. 11 It was also demonstrated that the activation of β-catenin by MT prevents the damage of neuron cells caused by prion-induced neurotoxicity. Previous studies have demonstrated that the concomitant application of MT and Wnt-4 promoted the differentiation of bovine amniotic epithelial cells into neuron cells and aided the recovery from SCI.…”

The Science and Clinical Applications of Placental Tissues in Spine Surgery

“…12–14,37–39,44 AECs and umbilical cord tissue and cord blood have been particular targets in this line of research. In vivo animal models have shown that AECs can promote neural cell differentiation, 65 reduce secondary neural damage associated with inflammation and apoptosis associated with SCI, 66 modulate spinal cord microglia activity to suppress mechanical allodynia, 67 promote remyelination of nerve fibers and promote sprouting of nerve fibers, 68 and improve functional recovery. 68–70 …”