**Neuroplasticity in Spiny Mice Following Stroke Without Tissue Regeneration**
Stroke is a leading cause of disability worldwide, often resulting in long-term motor, sensory, and cognitive impairments. The brain’s ability to recover from stroke depends on a phenomenon known as neuroplasticity—the capacity of neural networks to reorganize and adapt in response to injury. While most mammals, including humans, exhibit limited neuroplasticity after stroke, recent research has turned to unique animal models to better understand the mechanisms underlying brain recovery. One such model is the spiny mouse (*Acomys spp.*), a rodent species known for its remarkable regenerative abilities in peripheral tissues. Interestingly, studies have shown that spiny mice exhibit robust neuroplasticity following stroke, even in the absence of tissue regeneration in the brain. This article explores the mechanisms of neuroplasticity in spiny mice, their implications for stroke recovery, and potential applications for human medicine.
—
### **The Spiny Mouse: A Unique Model for Stroke Research**
Spiny mice are small rodents native to Africa and the Middle East, renowned for their extraordinary regenerative capabilities. Unlike most mammals, spiny mice can regenerate skin, ear tissue, and even parts of internal organs without scarring. This has made them a valuable model for studying wound healing and tissue regeneration. However, their central nervous system (CNS) does not exhibit the same regenerative capacity. Like humans, spiny mice experience permanent tissue loss following a stroke, making them an intriguing model for studying neuroplasticity in the absence of brain tissue regeneration.
—
### **Neuroplasticity in the Spiny Mouse Brain**
Despite the lack of tissue regeneration in the CNS, spiny mice demonstrate remarkable functional recovery after stroke. This recovery is attributed to enhanced neuroplasticity, which involves several key processes:
1. **Axonal Sprouting and Synaptic Remodeling**
Following a stroke, spiny mice exhibit increased axonal sprouting, where surviving neurons extend new projections to compensate for lost connections. Synaptic remodeling also occurs, with existing synapses strengthening or forming new connections to restore neural circuits. These processes are particularly pronounced in the peri-infarct region—the area surrounding the stroke-induced lesion.
2. **Recruitment of Neural Progenitor Cells**
While spiny mice do not regenerate brain tissue, they show an increased recruitment of neural progenitor cells (NPCs) to the damaged area. These NPCs do not replace lost neurons but may support recovery by secreting neurotrophic factors, which promote the survival and growth of existing neurons.
3. **Reorganization of Functional Networks**
Functional MRI studies in spiny mice have revealed significant reorganization of brain networks following stroke. Regions of the brain that were not directly affected by the stroke take on new roles, compensating for lost functions. This reorganization is facilitated by the brain’s inherent plasticity and the ability of neurons to adapt to new tasks.
4. **Enhanced Glial Support**