Schizophrenia aetiology

The three disorders depression, schizophrenia and dementia are discussed in relation to the possible involvement of omega-3 fatty acids in these diseases, that is a deficiency may be involved in the aetiology of these diseases. 

Thus there is evidence, albeit circumstantial, of a disturbance of glutamate systems in the disease. In addition there is evidence of GABAergic deficits. Adding to the relevance of these hypotheses of amino acid transmitter dysfunction is the opportunity to relate neurochemical changes directly to a neuronal pathology and, with some further extrapolation, to the aetiology of schizophrenia. 

McGuffin P, Asherson P, Owen M, Farmer A (1994) The strength of the genetic effect. Is there room for an environmental influence in the aetiology of schizophrenia Br J Psychiatry 164 593-599... 

Crow TT 1995 Aetiology of schizophrenia an evolutionary theory. Int Clin Psychopharmacol (suppl 3) 10 49-56... 

The Reelin gene has been implicated in the aetiology of neurodevelopmental disorders such as schizophrenia and autism (Abrahams Geschwind, 2008 Fatemi, 2005 Keller Persico, 2003). Interestingly, a common variant of the Reelin gene has been found to increase schizophrenia risk only in women (Shifman et al., 2008), confirming that gene-sex interactions can be important for neurodevelopmental disorders. 

M7. Mee, T. J. X., and Smith, ]. A., High pressure chromatographic separation of some biogenic amines and derivatives implicated in the aetiology of schizophrenia. In High Pressure Liquid Chromatography in Clinical Chemistry (P. F. Dixon, C. H. Gray, C. K. Lim, and M. S. Stoll, eds.), pp. 119-124. Academic Press, New York, 1976. 

The other psychotomimetic compounds which contain an indole nucleus, have been much less extensively studied than LSD. Bufotenine is found in the toad, Bufo marinas, in a toadstool and in cohaba snuff both bufotenine and TV Wdimethyltryptamine (which also occurs in cohaba snuff) can be formed in vitro from 5-hydroxytryptamine and there have been reports that the urine of schizophrenic patients contains bufotenine . This finding could not be confirmed in a later study and it seems unlikely that bufotenine production is an aetiological factor in schizophrenia. 

Very recent studies show that the production and release of the catecholamine neurotransmitters dopamine and norepinephrine can also be influenced by physiologic variations in brain levels of their dietary precursor, tyrosine . This relationship could have an even greater impact on clinical problems than the uses described above for choline s effects on acetylcholine norepinephrine-containing neurons are involved in a very large number of physiological mechanisms, both inside and outside the brain (e.g. control of blood pressure), and dopaminergic neurons have clearly been implicated in the aetiology of Parkinson s disease, schizophrenia... 

Pyridoxine has been proposed a treatment for elevated levels of homocysteine, which is believed to be involved in the aetiology of coronary artery disease. There is some evidence that it promotes turnover of homocysteine. There is evidence that it can improve immtme function in the elderly when administered at levels about 2-3 x RDA. There is some evidence that pyridoxine supplementation may improve cognitive function in the elderly although not mood. There is some evidence that pyridoxine may reduce the risk of kidney stone formation. Pyridoxine has been used for many years in the treatment of morning sickness and there is some evidence that it is effective when used at levels of 25 mg every 8 hours. It has been used in treating premenstrual syndrome and there is some evidence that it is effective. It is recommended that pyridoxine supplementation is used with dmgs such as isoniazid and penicillamine that deplete its levels. Lar doses (0.1-1 g) have been used in the treatment of schizophrenia and it has been found that pyridoxine can interfere with the actions of LDOPA and phenytoin. 

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