Dopamine-prolactin pathway potentially contributes to the schizophrenia and type 2 diabetes comorbidity.
Schizophrenia (SCZ) and type 2 diabetes (T2D) are clinically associated, and common knowledge attributes this association to side effects of antipsychotic treatment. However, even drug-naive patients with SCZ are at increased risk for T2D. Dopamine dysfunction has a central role in SCZ. It is well-known that dopamine constitutively inhibits prolactin (PRL) secretion via the dopamine receptor 2 (DR2D). If dopamine is increased or if dopamine receptors hyperfunction, PRL may be reduced. During the first SCZ episode, low PRL levels are associated with worse symptoms. PRL is essential in human and social bonding, as well as it is implicated in glucose homeostasis. Dopamine dysfunction, beyond contributing to SCZ symptoms, may lead to altered appetite and T2D. To our knowledge, there are no studies of the genetics of the SCZ-T2D comorbidity focusing jointly on the dopamine and PRL pathway in the attempt to capture molecular heterogeneity correlated to possible disease manifestation heterogeneity. In this dopamine-PRL pathway-focused-hypothesis-driven review on the association of SCZ with T2D, we report a specific revision of what it is known about PRL and dopamine in relation to what we theorize is one of the missing links between the two disorders. We suggest that new studies are necessary to establish the genetic role of PRL and dopamine pathway in SCZ-T2D comorbidity.
Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Florida College of Medicine, Jacksonville, FL, USA.|Department of Public Health Sciences, Penn State College of Medicine, Hershey, PA, USA.|Molecular Biology Laboratory, Bios Biotech Multi-Diagnostic Health Center, Rome, Italy.
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C
Gragnoli
Division of Child and Adolescent Psychiatry, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA.
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Reeves
Borland Health Sciences Library, University of Florida, Jacksonville, FL, USA.
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J
Reazer
Rocky Mountain Mental Illness Research Education and Clinical Center, Denver, CO, USA.|Veterans Integrated Service Network 5 MIRECC, Baltimore, MD, USA.|Department of Psychiatry, University of Maryland, Baltimore, MD, USA.
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Postolache
D015897:Comorbidity; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000378:metabolism*; D006801:Humans; D011388:Prolactin / Q000378:metabolism*; D012559:Schizophrenia / Q000150:complications* / Q000378:metabolism*
D011388:Prolactin