Table 1 Hydrogel scaffolds loaded with different GFs, small molecules and stem cells
From: Multimodal therapy strategies based on hydrogels for the repair of spinal cord injury
GFs, small molecules and stem cells | Advantages | Disadvantages | Hydrogel-based delivery system |
|---|---|---|---|
GFs | |||
Improving the axonal growth and promoting the formation of neural stem cells | Short half-life, low stability, and poor penetrativity of the BSCB | Hydrogel made by HA and MC | |
Reducing the number of apoptotic neurons and the inflammatory reaction | Â | A thermosensitive HP hydrogel loaded with aFGF | |
Decreasing glial scar formation | Â | A thermosensitive HP hydrogel loaded with bFGF | |
HGF [58] | Promoting neurogenesis and inhibiting glial scar formation | Â | A gelatin-FA hydrogel scaffold loaded with HGF combined with a CBD |
Small molecules | |||
Baricitinib [59] | Decreasing inflammation and promoting axonal regeneration | The first-pass effect; The special structure of BSCB and BBB | An injectable thermos-sensitive hydrogel loaded with baricitinib |
Decreasing inflammation and protecting neurons | Â | A chitosan-collagen hydrogel loaded with serpin | |
Cab [62] | Reducing inhibitory scar formation and promoting axonal growth | Â | A biodegradable and injectable hybrid hydrogel |
Anti-inflammatory and anti-apoptotic; Promoting axonal growth | Â | A dual-drug delivery system based on alginate hydrogel | |
Stem cells | |||
Promoting neurogenesis, enhancing neuronal cell survival and inhibiting glial scar formation | Limited survival and low implantation rate and the failure of crossing the BBB | An agarose/carbomer-based hydrogel; A 3D gelatin sponge scaffold; Aligned fibrin hydrogel scaffold; Chitosan-based hydrogel | |
Promoting tissue regeneration and modulating the immune system | Â | A three-dimensional hydrogel scaffold based on agarose/carbomer hydrogel | |
hUC-MSCs [70] | Abundant resources, convenient collection and low immunogenicity | Â | A dual-enzymatically cross-linked gelatin hydrogel |
Endometrium stem cells [71] | Low immunogenicity, high proliferation rate and the plasticity to differentiate into other cells | Â | Fibrin hydrogel |
Altering the diseased environment | Â | Optimized hydrogel based on gelatin | |
Anti-inflammatory | Â | HP hydrogel | |
Creating a suitable environment | Â | Collagen and fibrin hydrogels | |