Aspects of this invention are related to the use of N-
desmethyl ruboxistaurin and pharmaceutically acceptable formulations thereof to modulate GSK3|3 signaling. Some aspects of the invention relate to the use of N-
desmethyl ruboxistaurin to inhibit
protein kinase C. Some aspects of the invention provide methods of using N-
desmethyl ruboxistaurin in the treatment of subjects having a neurological
disease and / or psychiatric disorder, including Alzheimer's
disease,
frontotemporal dementia, behavioral complications of
dementia, bipolar disorder, depression,
schizophrenia, Parkinson's
disease, or
neuroinflammation. Some aspects of this invention provide methods of using N-desmethyl ruboxistaurin in treating conditions associated with
diabetes mellitus or its complications, or
ischemia,
inflammation,
pulmonary hypertension, congestive
heart failure, cardiovascular disease, dermatological disease, or
cancer. Some aspects of the invention relate to the use of N-desmethyl ruboxistaurin as an alternative to ruboxistaurin, with a better pharmacokinetic profile, lower potential for
prolongation of the electrocardiogram
QT interval, and / or a lower potential for adverse
drug interactions. In some embodiments, N-desmethyl ruboxistaurin is administered in combination with
lithium or other treatments for bipolar disorder.