The prevalence of diabetes and co-morbid diseases, especially in developing countries, may have already exceeded estimates. Accumulating reports indicate considerable underpinnings in the mechanisms of the aetiopathogenesis of metabolic syndrome, bipolar disorder, epilepsy and, recently, substance addiction. Continuing evidence incriminates dysfunction in genetic, mitochondrial and inflammatory cascade mechanisms as contributory factors to the dysregulation of neurotrophic, serotonergic, dopaminergic, adrenergic, glutamatergic, GABAergic and autophagic pathways. There may also be co-incident dysregulation of the global anti-oxidant network, the endogenous digitalis system, the vasopressin signalling and the hypothalamo-pituitary-adrenal axis. Nuclear factor-kappa B (NF-kappa B) signaling and reactive oxygen species lead to activation of the mammalian target of rapamycin complex I (mTORCI) and this process may be central to the aetiopathogenesis of drug addiction, obesity, foetal programming, diabetes mellitus, epilepsy and bipolar disorder. Antiglycaemics such as cannabinoid CB2 agonists, metformin, artesunate and valproate; insulin-mimetics such as glucagon-like peptide-I (GLP-I) and its analogues; phytomedicines from garlic and curcumin are now shown to exhibit neuroprotective effects. These agents which may down-regulate inflammatory cytokines, upregulate endothelial nitric oxide (eNOS) and peroxisome proliferator-activated receptor alpha (PPAR-α) signalling, attenuate mitochondrial dysfunction, enhance the actions of glucagon-like peptide-I (GLP-I), inhibit mTOR, NF-kappa B, interleukin-I β and glycogen synthase kinase-3 β stand to be of benefit in these illnesses which demonstrate considerable overlay in their aetopathogenic mechanisms. Underpinnings and bidirectional relationships between the metabolic syndrome and mental health disorders may pave way for common new fronts to drug development in translational cardiovascular psychiatry and neurology.
