身体炼和与阿尔茨海默病相关的机制:肠-大脑轴是否参与?

Alzheimer's Disease (AD) is a continually advancing neurodegenerative disorder, distinguished by escalating memory loss, cognitive dysfunction, and dementia. The disease unfolds in three stages: preclinical, mild cognitive impairment (MCI), and dementia. Its onset is insidious, and the progression gradual, with the cause not well explained by other disorders.
The clinical diagnosis of AD hinges on the presence of memory and other cognitive impairments. Biomarkers, such as changes in Aβ...

Irritable Bowel Syndrome (IBS) is characterized by functional disturbances in the gastrointestinal system, presenting a cluster of symptoms without evident structural or biochemical abnormalities. It primarily affects the large intestine and may cause abdominal pain, bloating, excessive gas, diarrhea, constipation, or both.
IBS is a chronic condition that can persist over a long period or recur frequently.
The pathogenesis of IBS involves a complex interplay of the following factors:
Altered...

The Enteric Nervous System (ENS) plays a pivotal role in regulating gastrointestinal or GI motor activity. This complex network of nerves, deeply embedded within the gut wall, responds to changes in the gut environment and receives input from both the autonomic nervous system and the central nervous system. By doing so, the ENS operates various programs tailored to the body's nutritional status and needs.
During periods of fasting, the ENS initiates the migrating myoelectric complex, a...

The gastrointestinal elimination process involves a complex interplay of neural and hormonal mechanisms that coordinate the final waste removal from the body. This intricate operation encompasses the absorption of water and electrolytes, vital for transforming the remaining indigestible food matter into feces. The large intestine is pivotal in water and electrolyte absorption, forming feces from unabsorbed minerals, undigested food, bacteria, bile pigments, and shed epithelial cells. Essential...

Digestion begins with a cephalic phase that prepares the digestive system to receive food. When our brain processes visual or olfactory information about food, it triggers impulses in the cranial nerves innervating the salivary glands and stomach to prepare for food.

Neurotransmitters are integral to the brain's communication system, enabling neurons to transmit signals across synapses. This chemical exchange underpins various cognitive functions, including memory processes. The role of neurotransmitters in memory is multifaceted, influencing the encoding, consolidation, and retrieval of memories through their action on different neural circuits.
 Glutamate and Synaptic Plasticity
Glutamate, the brain's main excitatory neurotransmitter, is...