In Defense of the Medical Model in Psychiatry

Unfortunately diabetes can be a side effect of atypical "antipsychotics". However, bad side effects of psychiatric drugs do not mean that the medical model is not valid. Ref. 1 gives information supporting the medical model in psychiatry.

Tryptophan

A great deal of research has been done on tryptophan, in part because it is a precursor of both niacin and serotonin (2). Corn is known to be low in tryptophan. It has been used in tryptophan depletion experiments in rats. Amino acids in general are known to be precursors of certain neurotransmitters including monoamines (3). These same amino acids are found in the diet.

Mood Disorders

Many biological markers have been reported in mood disorders (4, 5). The prefrontal cortex has been implicated (6).

Genetics

Positive findings have been reported in genetic studies (7).

Glutamate

Abnormal glutamate findings have been reported (8, 9).

Depression

Tryptophan has been implicated in depression (10). This reference is very interesting so I will elaborate on it. The authors used a mouse model for depression. It was a joint effort between French scientists and scientists from Illinois.

"We report that peripheral administration of lipopolysaccharide (LPS) activates IDO and culminates in a distinct depressive-like behavioral syndrome, measured by increased duration of immobility in both the forced swim and tail suspension tests."J.C. O'Connor,¹ M.A. Lawson,¹ C. André,² M. Moreau,² J. Lestage,² N. Castanon,² K.W. Kelley,^1,3 and R. Dantzer^1,31 Integrative Immunology & Behavior, INRA-CNRS-University Victor Segalen Bordeaux II, Bordeaux, France² Department of Animal Sciences, College of Agricultural, Environmental and Consumer Sciences, INRA-CNRS-University Victor Segalen Bordeaux II, Bordeaux, France³ Department of Pathology, College of Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA This quote is from Ref. 10. Whether or not this is an accurate model of human depression is not clear, but there is other data implicating tryptophan in depression (11, 12).Interferon This is a drug used to treat cancer and virus infections. It is a cytokine. Unfortunately this drug can cause depression as a side effect (13, 14). It seems that this happens because the interferon increases tryptophan metabolism (15, 16).Conclusions There is massive evidence that mental disorders are organic. They appear to be caused by increased tryptophan metabolism. What causes the increased tryptophan metabolism is not yet completely clear. More research is needed. The medical model is valid. Tryptophan is found in the diet, so this opens the door towards nutritional treatments of mental disorders. The dietary manipulation of tryptophan is suggested. A low tryptophan diet is a possibility. More information on depression is given in Ref. 17. Anxiety is a symptom of depression and of other mental disorders.

References

1. www.associatedcontent.com/article/2841144/post_traumatic_stress_disorder.html

2. Biggio G, Fadda D, Fanni P, Tagliamonte A, Gessa GL. Rapid depletion of serum tryptophan, brain tryptophan, serotonin and 5-hydroxyindoleacetic acid by a tryptophan-free diet. Life Sci. 1974;14:1321-1329.

3. Fernstrom JD. Role of precursor availability in control of monoamine biosynthesis in brain. Physiol Rev. 1983;63:484-546.

4. Öngür D, Drevets WC, Price JL. Glial reduction in the subgenual prefrontal cortex in mood disorders. Proc Natl Acad Sci U S A. 1998;95(22):13290-13295.

5. Rajkowska G. Postmortem studies in mood disorders indicate altered numbers of neurons and glial cells. Biol Psychiatry. 2000;48(8):766-777.

6. Drevets WC, Price JL, Simpson JR, Todd RD, Reich T, Vannier M, et al. Subgenual prefrontal cortex abnormalities in mood disorders. Nature. 1997;386:824-827.

7. Hattori E, Liu C, Badner JA, Bonner TI, Christian SL, Maheshwari M, et al. Polymorphisms at the G72/G30 gene locus, on 13q33, are associated with bipolar disorder in two independent pedigree series. Am J Hum Genet. 2003;72(5):1131-1140.

8. Sanacora G, Rothman DL, Mason G, Krystal JH. Clinical studies implementing glutamate neurotransmission in mood disorders. Ann N Y Acad Sci. 2003;1003:292-308.

9. ABNORMAL GLUTAMATERGIC NEUROTRANSMISSION AND NEURONALGLIAL INTERACTIONS IN ACUTE MANIA. Dost Öngür, J. Eric Jensen, Andrew P. Prescot, Caitlin Stork, Miriam Lundy, Bruce M. Cohen, and Perry F. RenshawBiol Psychiatry. Author manuscript; available in PMC 2009 October 15.PMCID: PMC2577764 Published in final edited form as: Biol Psychiatry. 2008 October 15; 64(8): 718-726. Published online 2008 July 7. doi: 10.1016/j.biopsych.2008.05.014.
10. Lipopolysaccharide-induced depressive-like behavior is mediated by indoleamine 2,3-dioxygenase activation in mice. J.C. O'Connor, M.A. Lawson, C. André, M. Moreau, J. Lestage, N. Castanon, K.W. Kelley, and R. DantzerMol Psychiatry. Author manuscript; available in PMC 2009 November 1.PMCID: PMC2683474Published in final edited form as: Mol Psychiatry. 2009 May; 14(5): 511-522. Published online 2008 January 15. doi: 10.1038/sj.mp.4002148.
11. Yirmiya R. Endotoxin produces a depressive-like episode in rats. Brain Res. 1996;711(1-2):163-74.
12. Prepartum Depressive Symptoms Correlate Positively with C-Reactive Protein Levels and Negatively with Tryptophan Levels: A Preliminary Report

Debra A. Scrandis, Patricia Langenberg, Leonardo H. Tonelli, Tehmina M. Sheikh, Anita C. Manogura, Laura A. Alberico, Tracey Hermanstyne, Dietmar Fuchs, Hugh Mighty, Jeffrey D. Hasday, Kalina Boteva, and Teodor T. PostolacheInt J Child Health Hum Dev. Author manuscript; available in PMC 2008 October 15.PMCID: PMC2567806 Published in final edited form as: Int J Child Health Hum Dev. 2008 August; 1(2): 167-174.
13. Raison CL, Capuron L, Miller AH. Cytokines sing the blues: Inflammation and the pathogenesis of depression. Trends Immunol. 2006;27(1):24-31.
14. Capuron L, Ravaud A, Dantzer R. Early depressive symptoms in cancer patients receiving interleukin 2 and/or interferon alfa-2b therapy. J Clin Oncol. 2000;18(10):2143-51.
15. Reichenberg A, Yirmiya R, Schuld A, et al. Cytokine-associated emotional and cognitive disturbances in humans. Arch Gen Psychiatry. 2001;58:445-52.
16. Wichers MC, Kenis G, Koek GH, Robaeys G, Nicolson NA, Maes M. Interferon-17. Maes M, Lin A, Ombelet W, et al. Immune activation in the early puerperium is related to postpartum anxiety and depression symptoms. Psychoneuroendocrinology. 2000;25(2):121-37.