Table 1.
Drugs manipulating cAMP and its downstream signaling molecules
| Drug type | Activity | Outcome | Reference(s) |
|---|---|---|---|
| cAMP analogues | |||
| 8-Br-cAMP | Cyclic adenosine monophosphate (cAMP) analogue | Mouse neonatal mature astrocytes upregulated antioxidant-related genes and downregulated cell death-related genes after treatment | Paco et al., 2016 |
| db-cAMP | Injection into adult rat dorsal root ganglion (DRG) before spinal cord injury (SCI) resulted in an increase in the number of axons regrowing across the injury | Neumann et al., 2002; Qiu et al., 2002 | |
| Improved functional recovery after spinal contusion in adult female rats | Pearse et al., 2004 | ||
| Increase in axonal sprouting within the glial scar | Xia et al., 2017 | ||
| Sp-cAMPs | Adult rat DRG neurons switched their repulsive response to myelin-associated glycoprotein (MAG) gradients to attraction after treatment | Murray et al., 2009b | |
| Epac agonists | |||
| 8-Me-cAMP | General exchange protein activated by cAMP (Epac) agonist | Agonist first described | Enserink et al., 2002 |
| Rat neonatal mature astrocytes increased intracellular calcium levels after treatment | Di Cesare et al., 2006 | ||
| Adult rat DRG neurons cultured on spinal cord tissue increased neurite outgrowth after treatment | Murray and Shewan, 2008 | ||
| Adult rat DRG neurons switched their repulsive response to MAG gradients to attraction after treatment | Murray et al., 2009b | ||
| BV-2 cells significantly decreased their phagocytotic behaviour after treatment | Steininger et al., 2011 | ||
| In vitro embryonic rat spinal cord culture model of SCI increased neurite outgrowth after treatment | Boomkamp et al., 2014 | ||
| Adult rat DRG neurons increased neurite outgrowth after treatment | Wei et al., 2016 | ||
| S-220 | Specific Epac2 agonist | Agonist first described | Schwede et al., 2015 |
| Neonatal rat DRG neurons showed a strong turning behaviour towards treatment | Guijarro-Belmar et al., 2019 | ||
| Neonatal rat DRG and cortical neurons increased neurite outgrowth after treatment, even in an inhibitory environment | |||
| Ex vivo model of SCI increased neurite outgrowth and reduced glial activation after treatment | |||
| -Improved locomotor recovery after treatment in an in vivo rat SCI model | |||
| Epac antagonists | |||
| ESI-05 | Specific Epac2 antagonist | Antagonist first described | Tsalkova et al., 2012 |
| Adult rat DRG neurons reduced neurite outgrowth after treatment | Wei et al., 2016 | ||
| Neonatal rat DRG and cortical neurons decreased neurite outgrowth after treatment | Guijarro-Belmar et al., 2019 | ||
| ESI-09 | General Epac antagonist | Antagonist first described | Almahariq et al., 2013 |
| Embryonic hippocampal neurons decreased neurite outgrowth after treatment | Munoz-Llancao et al., 2015 | ||
| Others | |||
| Rolipram | Phosphodiesterase type 4 inhibitor | Improved functional recovery after treatment in spinal contusion in adult female rats | Pearse et al., 2004 |
| Increased axonal plasticity and improved recovery after treatment in spinal hemisection in adult rats | Nikulina et al., 2004 | ||
| Improved locomotor abilities after treatment in spinal contusion in adult rats | Costa et al., 2013 | ||
| In vitro embryonic rat spinal cord culture model of SCI increased neurite outgrowth after treatment | Boomkamp et al., 2014 | ||
| KT-5720 | Protein kinase A antagonist | Discussion of antagonist specificity | Murray, 2008 |
| In vitro embryonic rat spinal cord culture model of SCI increased neurite outgrowth after treatment | Boomkamp et al., 2014 |