Reflection: How Parasitic Helminths Adapt to Environmental Hypoxia

My Wanderings in Helminth Biochemistry

Abstract

From 1978 to 2014, I was engaged in parasitology education and research at Juntendo University School of Medicine. During this period, I conducted research in the United States from 1985 to 1987. Furthermore, from October 1991 to March 1992, I was dispatched to the Federal University of Pernambuco in Brazil as a parasitology expert on an international project through the Japan International Cooperation Agency. I would now like to trace the research conducted by our research group, including that in the United States and Brazil.
The main topics of this paper are as follows:
1. Mitochondrial respiratory chains from the larval and adult stages of Ascaris suum, with special reference to electron transfer complex II and quinone components, both of which are key molecules in aerobic-anaerobic transition in nematode energy metabolism.
2. The respiratory chain in mammalian mitochondria and mitochondrial diseases caused by respiratory chain deficiencies, which I studied in the United States.
3. The mitochondrial respiratory chain of the free-living nematode Caenorhabditis elegans as a model of Ascaris larval-stage mitochondria.
4. Adult A. suum muscle-derived soluble cytochrome b₅: a key cytoplasmic molecule for adaptation to environmental hypoxia.
5. The functions and morphology of mitochondria in adult Paragonimus westermani, which make the host’s lung more habitable by forming cysts, the oxygen tensions of which are higher than those in the small intestine.