Glucose metabolism is important for normal cellular process. It produces neurotransmitters and adenosine triphosphate (ATP), giving brain cells the energy to perform their normal function. Adequate glucose supply is essential for consciousness and cognitive functions indicating that glucose is critical for the normal operation of the mind, memory, and emotion. Conventional belief is that glucose is supplied to the brain by two pathways working in conjunction with each other. The first pathway supplies glucose from plasma within the capillaries inside the brain to the astrocytes where glycolysis takes place which then feeds lactate into the neurons. The first pathway mainly involves the whole cerebral cortex. The second pathway transports the glucose as well as insulin present in the plasma within the capillaries, hereinafter referred to as plasma glucose and plasma insulin respectively, to the spaces between the blood and brain side of the blood brain barrier, hereinafter referred to as BBB, to the brain's interstitial fluid which then carries the glucose and insulin to the brain proper. This second pathway also involves the whole cerebral cortex. The proponents of this second pathway do not consider the cerebral spinal fluid, hereinafter CSF, as a major component or factor of that pathway. The rationale given by the proponents of this second pathway is the observed low glucose concentration found in the CSF. This low glucose concentration is presently explained by a leakage of glucose to the CSF while the main flow of glucose occurs between the blood and brain side of the BBB.
These pathways do not however explain all of the phenomena occurring in the brain. The proceeding are some of the unexplained phenomena:
A. The absence of the correlation between the glucose metabolism and the cerebral blood flow (Suda, S., Shinohara, M., Miyaoka, M., Lucignani, G., Kennedy, C., & Sokoloff, L. The lumped constant of the deoxyglucose method in hypoglycemia: effects of moderate hypoglycemia on local cerebral glucose utilization in the rat. Journal of Cerebral Blood Flow and Metabolism, 10, pp. 499–509. 1990. International Society for Cerebral Blood Flow and Metabolism. Bethesda, Md. 20892-1180).
B. Uneven glucose distribution in the cortex after severe hypoglycemia episode (Agrdh, C.-D., Kalimo, H., Olsson, Y., and Siesjo, B. K. Hypoglycemia brain injury. Acta Neuropathologica, 50, pp. 31–41. 1980. Springer-Verlag. Heidelberg, Germany; Kalimo, H. & Olsson, Y. Effects of severe hypoglycemia on the human brain. Acta Neurologica, 62, pp. 345–356. 1989. Munksgaard International Publishers Ltd. New York, N.Y.).
C. Different types of cell injuries under severe hypoglycemia (Agrdh, C.-D., Kalimo, H., Olsson, Y., and Siesjo, B. K. Hypoglycemia brain injury. Acta Neuropathologia, 50, pp. 31–41. 1980. Springer-Verlag. Heidelberg, Germany).
D. Different recovery rates in the brain cells after severe hypoglycemia followed by glucose injection (Agrdh, C.-D., Kalimo, H., Olsson, Y., and Siesjo, B. K. Hypoglycemia brain injury. Acta Neuropathologia, 50, pp. 31–41. 1980. Springer-Verlag. Heidelberg, Germany).
E. Different survival rates in the brain cells after severe hypoglycemia (Agrdh, C.-D., Kalimo, H., Olsson, Y., and Siesjo, B. K. Hypoglycemia brain injury. Acta Neuropathologia, 50, pp. 31–41. 1980. Springer-Verlag. Heidelberg, Germany).                F. The relation between the thyroid hormones and mental disturbance (Bauer, M. S. & Whybrow, P. C. Thyroid hormones and the central nervous system in affective illness: interactions that may have clinical significance. Integrative Psychiatry, 6, pp. 75. 1988. Elsevier Science Publishing Co., Inc. New York, N.Y. 10017; Joffe, T. R., Sokolov, T. H. S. Thyroid hormones, the brain, and affective disorders. Critical Reviews in Neurobiology, 8, pp. 45–63. 1994. Begell House, Inc. Congers, N.Y. 10920).        
G. How the cerebral spinal fluid flows against gravity from the choroid plexus to the sagittal sinus (Nolte, J. The Human Brain: An Introduction to Its Functional Anatomy, pp. 85. 1999. Mosby-Year Book, Inc. St. Louis, Mo. 63146).
H. Ventricular enlargement observed in dementia (Rao, C. V. G. K. Degenerative disease and hydrocephalus. Cranial MRI and CT, pp. 181–259. 1999. Mc Graw-Hill. New York. N.Y.) and in severe hypoglycemia (Kalimo, H & Olsson, Y. Effects of severe hypoglycemia on the human brain. Acta Neurologica Scandinavica, 62, pp. 345–356. 1989. Munksgaard International Publishers Ltd. Malden, Mass. 02148-5018)
I. Apoptosis in Alzheimer's disease (Connor, B. & Dragunow, M. The role of neuronal growth factors in neurodegenerative disorders of the human brain. Brain Research Review, 27, pp. 1–39. 1998. Elsevier/North-Holland Biomedical press. Amsterdam, Netherlands).
J. Lower CSF insulin and higher plasma insulin in more advanced Alzheimer's disease (Craft, S., Peskind, E., Schwartz, M. W., Schellenberg, G. D., Raskind, M., & Porte, D. Jr. Cerebrospinal fluid and plasma insulin levels in Alzheimer's disease: relationship to severity of dementia and apolipoprotein E genotype. Neurology, 50, pp. 164–168. 1998. The American Academy of Neurology. Lippincott Williams & Wilkins, Inc. St. Paul, Minn. 55116).
K. Beta-amyloid precursor protein abnormality in Alzheimer's disease (Cerebromicrovascular pathology In Alzheimer's disease compared to normal aging. Gerontology, 43. 1997. S. Karger Publishers, Inc. Farmington, Conn.).
L. Tau protein abnormality in Alzheimer's disease (Cerebromicrovascular pathology in Alzheimer's disease compared to normal aging. Gerontology, 43. 1997. S. Karger Publishers, Inc. Farmington, Conn.).
M. Altered peptidase activities in Alzheimer's disease (Yasuda M, Maeda K, Kakigi T, Minamitani N, Kawaguchi T, & Tanaka T. Neuropeptides, 29. 1995. Harcourt Brace & Co. Ltd. Kent DA145 HP).
N. Abnormal neuropeptides in Alzheimer's disease (Heiling M, Sjogren M, Blennow K, Ekman R, & Wallin A. Biological Psychiatry, 38. 1995. Elsevier Science Inc. New York, N.Y. 10010-5107; Sekiya K, Haiji M, Fukahori M, Takahanagi R, Ohashi M, Kurose S, Oyama M, Tateishi K, Funakoshi A, & Nawata H. Neuroscience Letters, 177. 1994. Elsevier Science Ltd. New York, N.Y. 10010).
O. The reason for the inability of CT scan and Magnetic Resonance Imaging (MRI) to detect mental illnesses and neuro degenerative diseases.
This invention shows that the above unexplained phenomena occurring in the brain is due to the presence of an alternate glucose pathway different from the second pathway described above. This alternate glucose pathway also works in conjunction with the first pathway and an insulin pathway occurring at the cortex cell layer I–III, possibly IV, in the brain and the spine. The presence of elevated levels of some biological materials in the CSF like cortisol, the uneven distribution of glucose in the cerebral cortex and the uneven damage observed on the brain cells under severe hypoglycemia, the absence of correlation between the glucose metabolism and the cerebral blood flow (CBF) are just some observation that justifies the existence of the proposed alternate glucose path way. This alternate glucose pathway when applied in conjunction with the other pathways explains the motor function, the functions of memory, mind and emotion, the effect of the thyroid hormones to mental disorders, dementia in cerebral ischemic infarction, hypoglycemia, Alzheimer disease, autism, dementia, and psychiatric illness.
It is therefore an object of this invention to show the presence of an alternate glucose pathway.
It is also an object of this invention to show the importance of collecting and testing the CSF for the diagnoses of mental disorders and those disorders related to neurological illnesses which can not be diagnosed through Computed Tomography (CT scan) or Magnetic Resonance Imaging (MRI), hereinafter referred to as nondetectable neurological disorders. The mental disorders and nondetectable neurological disorders are collectively referred to herein as disorders.
It is also an object of this invention to provide a method for proving the presence of an alternate glucose pathway.
It is a further object of this invention to show that the alternate glucose pathway working in conjunction with the other pathways, explains the unexplained phenomena enumerated above.
It is likewise an object of this invention to provide an objective test for detecting mental disorders and nondetectable neurological disorders.
It is also an object of this invention to provide effective medications or facilitate the isolation or synthesis of effective medications utilizing the concept of this invention.
It is also an object of this invention to show that a medication to treat disorders should be readily available from the CSF.