The human amniotic epithelium confers a bias to differentiate toward the neuroectoderm lineage in human embryonic stem cells

Neural Markers Predict Tendon Healing Outcomes in an Ovine Achilles Tendon Injury Model: Spontaneous Repair Versus Amniotic Epithelial Cell-Induced Regeneration

Tendon injuries pose a clinical challenge due to tendons' limited recovery. Emerging evidence points to the nervous system's critical role in tendon healing, with neural markers NGF, NF-200, NPY, CGRP, and GAL modulating inflammation, cell proliferation, and extracellular matrix (ECM) remodeling. This study investigates the predictive role of selected neural markers in a validated ovine Achilles tendon injury model, comparing spatio-temporal expression patterns in regenerating tendons transplanted with amniotic epithelial stem cells (AECs) versus spontaneous healing (CTR) 14 and 28 days post-injury (p.i.). AEC-treated tissues showed a spatio-temporal modulation of NF-200, NGF, NPY, CGRP, GAL, and enhanced ECM remodeling, with greater cell alignment, lower angle deviation, and accelerated collagen maturation, with a favorable Collagen type 1 (COL1) to Collagen type 3 (COL3) ratio. Pearson's matrix analysis revealed significant positive correlations between NGF, CGRP, and GAL expression, along a positive correlation between the three neural markers and cell alignment and angle deviation. As opposed to CTR, in AEC-treated tendons, lower levels of NGF, CGRP, and GAL correlated positively with improved tissue organization, suggesting these markers may predict successful tendon regeneration. The findings highlight the neuro-mediated activity of AECs in tendon regeneration, with NGF, CGRP, and GAL emerging as key predictive biomarkers for tendon healing.

Prolactin drives cortical neuron maturation and dendritic development during murine embryonic stem cell differentiation

Introduction

Prolactin (PRL) is a pleiotropic hormone implicated in various physiological processes; however, its contribution to neurodevelopment, particularly early corticogenesis, remains insufficiently characterized. In this study, we investigate PRL's regulatory influence on the initial stages of cortical development, with an emphasis on its effects on neuronal and astrocytic differentiation.

Methods

We employed a standardized in vitro differentiation protocol to generate cortical neurons from mouse embryonic stem cells (mESCs). Prolactin receptor (PRLr) expression was evaluated in pluripotent stem cells, neural stem cells (NSCs), immature neurons, and mature neurons using both PCR and immunofluorescence. These analyses revealed dynamic changes in PRLr expression throughout the differentiation process. Additionally, cells were treated with varying concentrations of PRL during early and late differentiation phases, enabling assessment of its impact on neuronal phenotypic distribution and morphological complexity.

Results

Early PRL administration significantly enhanced the population of β-tubulin III + immature neurons, promoting neuronal survival without altering NSC proliferation. Furthermore, PRL treatment increased the abundance of Tbr1 + and NeuN + neurons, augmented dendritic complexity, and accelerated neuronal maturation. In contrast, PRL exposure at later stages of neural differentiation did not yield comparable effects. Notably, PRL delayed the maturation of protoplasmic astrocytes, although the total astrocyte population was not affected.

Discussion

These findings highlight PRL's pivotal role as a regulator of early corticogenesis by modulating neuronal survival, dendritic development, and astrocyte maturation. PRL thus emerges as a potential key factor in neurodevelopment, underscoring its importance in the hormonal regulation of neural differentiation and maturation. These insights may have broader implications for understanding the molecular and cellular mechanisms underlying normal and pathological neurodevelopment.