Hirano body
Encyclopedia
Hirano bodies are intracellular aggregates of actin
and actin-associated proteins first observed in the neuron
s (nerve cells) by Asao Hirano
in 1965.
Hirano bodies are found in the nerve cells of individuals afflicted with certain neurodegenerative disorders, such as Alzheimer's disease
and Creutzfeldt-Jakob disease
.
Hirano bodies are often described as rod-shaped, crystal-like, and eosinophilic (pink after staining with haematoxylin
and eosin
). They are frequently seen in hippocampal
pyramidal cells. An experimental model of Hirano body formation has been reported, using a genetically altered strain of the slime mold
Dictyostelium discoideum
.
Hirano bodies have been noted as a function of age without obvious underlying neurodegeration.
Actin
Actin is a globular, roughly 42-kDa moonlighting protein found in all eukaryotic cells where it may be present at concentrations of over 100 μM. It is also one of the most highly-conserved proteins, differing by no more than 20% in species as diverse as algae and humans...
and actin-associated proteins first observed in the neuron
Neuron
A neuron is an electrically excitable cell that processes and transmits information by electrical and chemical signaling. Chemical signaling occurs via synapses, specialized connections with other cells. Neurons connect to each other to form networks. Neurons are the core components of the nervous...
s (nerve cells) by Asao Hirano
Asao Hirano
is a Japanese physician, academic, medical researcher and neuropathologist. He is credited with having first observed Hirano bodies which are intracellular aggregates of actin and actin-associated proteins in the neurons .-Selected works:...
in 1965.
Hirano bodies are found in the nerve cells of individuals afflicted with certain neurodegenerative disorders, such as Alzheimer's disease
Alzheimer's disease
Alzheimer's disease also known in medical literature as Alzheimer disease is the most common form of dementia. There is no cure for the disease, which worsens as it progresses, and eventually leads to death...
and Creutzfeldt-Jakob disease
Creutzfeldt-Jakob disease
Creutzfeldt–Jakob disease or CJD is a degenerative neurological disorder that is incurable and invariably fatal. CJD is at times called a human form of mad cow disease, given that bovine spongiform encephalopathy is believed to be the cause of variant Creutzfeldt–Jakob disease in humans.CJD...
.
Hirano bodies are often described as rod-shaped, crystal-like, and eosinophilic (pink after staining with haematoxylin
Haematoxylin
Haematoxylin, hematoxylin, Natural Black 1, or C.I. 75290 is extracted from the heartwood of the logwood tree. When oxidized it forms haematein, a compound that forms strongly coloured complexes with certain metal ions, the most notable ones being Fe and Al salts. Metal-haematein complexes are used...
and eosin
Eosin
Eosin is a fluorescent red dye resulting from the action of bromine on fluorescein. It can be used to stain cytoplasm, collagen and muscle fibers for examination under the microscope. Structures that stain readily with eosin are termed eosinophilic....
). They are frequently seen in hippocampal
Hippocampus
The hippocampus is a major component of the brains of humans and other vertebrates. It belongs to the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory and spatial navigation. Humans and other mammals have two hippocampi, one in...
pyramidal cells. An experimental model of Hirano body formation has been reported, using a genetically altered strain of the slime mold
Slime mould
Slime mold or mould is a broad term describing protists that use spores to reproduce. Slime molds were formerly classified as fungi, but are no longer considered part of this kingdom....
Dictyostelium discoideum
Dictyostelid
The dictyostelids are a group of cellular slime molds, or social amoebae.-Slug behavior:When food is readily available they are individual amoebae, which feed and divide normally...
.
Hirano bodies have been noted as a function of age without obvious underlying neurodegeration.