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Updated: May 28, 2026
06:18
Assessing Lysosomal Alkalinization in the Intestine of Live Caenorhabditis elegans
Published on: April 13, 2018
Age-related lysosomal dysfunction: an unrecognized roadblock for cobalamin trafficking?
Hua Zhao1, Ulf T Brunk, Brett Garner
1Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW 2522, Australia. hz739@uowmail.edu.au
Cellular and Molecular Life Sciences : CMLS
|October 22, 2011
Summary
Vitamin B12 (cobalamin) deficiency impairs neuronal function, potentially contributing to cognitive decline. Impaired lysosomal processing of cobalamin may be a key factor in age-related neurodegenerative diseases.
Area of Science:
- Biochemistry
- Neuroscience
- Gerontology
Background:
- Vitamin B12, or cobalamin, is essential for human metabolism, including DNA synthesis and maintaining homocysteine homeostasis.
- Cobalamin deficiency is linked to impaired neuronal and peripheral nervous system function, potentially contributing to cognitive decline and dementia.
- Lysosomal function declines with aging, particularly in long-lived neurons.
Purpose of the Study:
- To review evidence suggesting impaired lysosomal processing of cobalamin in aging.
- To explore the role of lysosomal cobalamin processing in age-related neurodegenerative diseases.
Main Methods:
- Review of published human and animal studies.
- Analysis of biochemical pathways affected by cobalamin deficiency.
- Examination of the relationship between aging, lysosomal function, and cobalamin metabolism.
Main Results:
- Cobalamin deficiency impairs critical metabolic pathways and neuronal function.
- Lysosomal processing is crucial for cobalamin utilization.
- Aging is associated with decreased lysosomal function in neurons.
Conclusions:
- Impaired lysosomal processing of cobalamin may be a significant contributor to age-related neurodegenerative diseases.
- Further research is needed to elucidate the precise mechanisms linking lysosomal dysfunction and cobalamin metabolism in aging.
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