Method of treating brain tissue damages

Patent Number: 7,427,597

It is known that various endogenous repair processes exist after ischemic injury to the brain.  For example, in stroke patients, there is a correlation between improvement of neurological function and amount of circulating stem cells.  Attempts are being made to augment endogenous repair processes by administration of agents such as PACAP, prolactin, or erythropoietin.

The current patent teaches that secretoneurin can be administered locally after cerebral ischemia or stroke and induce a regenerative/protective effect.

Secretoneurin a 33 amino acid peptide made by a variety of endocrine cells and is found primarily in the adrenal medulla and posterior pituitary hypothalamus.  This peptide, also called chromogranin B has been previously shown to be angiogenic and a chemoattractant for endothelial and monocytic cells.

Although the patent is limited to local injections, the biology of secretoneurin is very interesting. 

For example, it was published that systemic administration of secretoneurin induces mobilization of both hematopoietic stem cells, as well as endothelial precursor cells (Kirchmair et al. Secretoneurin, an angiogenic neuropeptide, induces postnatal vasculogenesis. Circulation. 2004 Aug 31;110(9):1121-7).  Additionally, this neuropeptide has been shown to be controlled by the HIF-1 alpha transcription factor, being upregulated in conditions of hypoxia in a manner similar to VEGF and FGF (Egger et al. Hypoxia up-regulates the angiogenic cytokine secretoneurin via an HIF-1alpha- and basic FGF-dependent pathway in muscle cells. FASEB J. 2007 Sep;21(11):2906-17). 

Perhaps what is most interesting is that the inventors of the patent published that systemic administration of secretoneurin actually decreases extent of cerebral infarction, improves motor performance, and increased brain metabolic activity in the middle cerebral artery ligation rat model of stroke (Shyu et al. Secretoneurin promotes neuroprotection and neuronal plasticity via the Jak2/Stat3 pathway in murine models of stroke. J Clin Invest. 2008 Jan;118(1):133-48).  So it is unfortunately that they did not get claims to systemic use, which would be much more commercially attractive than needing to drill holes in the head to administer it.

View this patent on the USPTO website.