The outer membrane of cells is comprised of a lipid bilayer consisting of phospholipids, cholesterol, arachidonic acid, omega-3 fatty acids, and others. Embedded in the membrane are various proteins that play roles critical to the survival and function of the cell. Examples of membrane proteins of particular importance for neurons are: ion channels and ion ‘pumps which control neuron excitability; glucose and ketone transporters which are critical for energy metabolism, and receptors for a myriad of neurotransmitters, neurotrophic factors, and other inter-cellular signaling molecules. In this episode chemistry Professor Allan Butterfield talks about research showing a pivotal role for free radicals generated by the Alzheimer’s amyloid-peptide in triggering a chain reaction attack on membrane arachidonic acid resulting in the release of a toxic lipid fragment called 4-hydroxynonenal (HNE). HNE can bind irreversibly to certain amino acids on proteins (lysine, cysteine, histidine) thereby compromising the normal function of the protein. The Butterfield lab and my lab showed that binding of HNE to ion pump proteins, glucose transporters, and glutamate transporters renders neurons vulnerable to excitotoxicity in Alzheimer’s disease. Interventions that suppress membrane lipid peroxidation or detoxify HNE may prevent or ameliorate Alzheimer’s disease and other neurodegenerative disorders.

LINKS

Professor Butterfield’s webpage:

https://chem.as.uky.edu/users/dabcns

Review articles

https://journals.physiology.org/doi/full/10.1152/physrev.00030.2022

https://pmc.ncbi.nlm.nih.gov/articles/PMC7502429/pdf/nihms-1583713.pdf

https://pmc.ncbi.nlm.nih.gov/articles/PMC7085980/pdf/nihms-1566301.pdf

A fascinating feature of interactions between two people is that neural network activity patterns in their brain can become synchronized. In this episode Francesco Papaleo talks about research studies in which activities of neuronal networks are recorded simultaneously in interacting humans or mice. His work has recently focused on the role of interbrain synchronization in the prefrontal cortex in emotion recognition and empathy. He summarizes this research and its implications as follows:

Interacting brains operate as an integrated system, with neural dynamics coevolving over time. Neuronal synchronization across brains has been observed in a range of species, including humans, monkeys, bats, and mice. This inter-neural synchrony (INS) has been proposed as a potential mechanism facilitating social interaction by enabling the functional integration of multiple brains.. Individual responses, such as emotion processing or decision-making, are adjusted and updated based on information that is continuously exchanged among the interacting partners

LINKS

Dr. Papaleo’s webpage at the Italian Institute of Technology

https://www.iit.it/people-details/-/people/francesco-papaleo

Review article on multi-brain dynamics

https://www.sciencedirect.com/science/article/pii/S0149763424004342?via%3Dihub

Self-experience of another’s stress

https://www.nature.com/articles/s41593-024-01816-y

Cortical – cortical transfer during social interactions

https://www.nature.com/articles/s41593-024-01647-x

Prosocial vs selfish behaviors

https://www.nature.com/articles/s41593-022-01179-2

Neural networks in the brain are active 24/7 and so require a continuous supply of nutrients via the cerebral blood vessels. As we age the cerebral vascular system can become compromised resulting in damage to neurons and a consequent impairment of cognition. Cerebrovascular dementia is a major cause of morbidity and mortality in the elderly but can also occur in younger people as a consequence of genetic mutations. In this episode professor Thiruma Arumugam of LaTrobe University talk about the causes and consequences of cerebral small vessel disease. The good news is that there are several different measures people can take to reduce their risk for cerebrovascular dementia.

LINKS

Vascular dementia reviews

https://www.sciencedirect.com/science/article/pii/S1568163724000965?via%3Dihub

https://pmc.ncbi.nlm.nih.gov/articles/PMC6420146/pdf/emss-81050.pdf

Biomarkers of vascular dementia

https://www.sciencedirect.com/science/article/pii/S1568163724000655?via%3Dihub

Intermittent fasting and vascular dementia

https://pmc.ncbi.nlm.nih.gov/articles/PMC11224924/pdf/jomes-33-2-92.pdf