Related Experiment Video
Updated: Feb 1, 2026
05:31
Author Spotlight: Modeling an Aspect of Preeclampsia in Female Mice Using Hypoxic Human Placenta-Derived Small Extracellular Vesicles
Published on: January 26, 2024
1.4K
Higher physiological vulnerability to hypoxic exposure with advancing age in the human brain
Mark B Vestergaard1, Mette Lf Jensen2, Nanna Arngrim3
1Functional Imaging Unit, Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital Rigshospitalet, Glostrup, Denmark.
Summary
As people age, the aging brain shows reduced blood flow reactivity and oxygen consumption. This makes the brain more vulnerable to hypoxia and metabolic stress, impacting overall brain health.
Area of Science:
- Neuroscience
- Aging Research
- Human Physiology
Background:
- The aging brain undergoes significant structural, functional, and metabolic alterations.
- Understanding age-related changes in brain physiology is crucial for maintaining cognitive health.
Purpose of the Study:
- To investigate age-related changes in resting brain functions.
- To assess the vulnerability of human brain physiology to hypoxic exposure in vivo.
Main Methods:
- Magnetic resonance imaging (MRI) and spectroscopy were used.
- Evaluated gray and white matter volumes, cerebral blood flow (CBF), and oxygen consumption (CMRO2).
- Measured concentrations of lactate, N-acetylaspartate, and glutamate+glutamine.
Main Results:
- Advancing age correlated with impaired CBF reactivity to hypoxia (p=0.029).
- Decreased cerebral oxygen consumption (p=0.036) and increased lactate concentration (p=0.009) were observed with age.
- Increased resting cerebral lactate (p=0.007) suggests impaired waste clearance.
Conclusions:
- Diminished resilience to hypoxia and increased metabolic stress vulnerability contribute to age-related decline in brain health.
- Age-related increases in cerebral lactate may indicate compromised brain waste product clearance.
Related Concept Videos
01:26Aging
701
Aging is a complex biological phenomenon influenced by various processes that affect cellular and systemic functions. Several prominent theories attempt to explain its mechanisms, highlighting cellular limitations, oxidative damage, and hormonal changes as central factors in aging.
Cellular Clock Theory
The cellular clock theory posits that the human lifespan is closely tied to the finite capacity of cells to divide, a phenomenon governed by telomeres, which are protective caps at the ends of...
Cellular Clock Theory
The cellular clock theory posits that the human lifespan is closely tied to the finite capacity of cells to divide, a phenomenon governed by telomeres, which are protective caps at the ends of...
701
01:19The Effect of Aging on Tissues
3.5K
Several body functions deteriorate with age. The external signs of aging are easily identifiable. For example, the skin becomes dry, less elastic, and thins out, forming wrinkles. The skin of the face begins to appear looser due to a decrease in the levels of elastic and collagen fibers in the connective tissue. Additionally, melanin production in the hair follicle decreases with age, resulting in gray hair. Moreover, the senses of sight and hearing decline, so glasses and hearing aids may...
3.5K
02:22Overview of Advanced Functional Groups
29.8K
Functional groups are groups of atoms with specific chemical properties that occur within organic molecules and are sometimes denoted as “R”. Functional groups can “functionalize” a compound by enabling it to adopt different physical and chemical properties.
Types of Advanced Functional Groups
The table below summarizes some of the major functional groups in organic chemistry.
29.8K
00:56Extraction: Advanced Methods
1.2K
Metal ions can be separated from one another by complexation with organic ligands–the chelating agent– to form uncharged chelates. Here, the chelating agent must contain hydrophobic groups and behave as a weak acid, losing a proton to bind with the metal. Since most organic ligands used in this process are insoluble or undergo oxidation in the aqueous phase, the chelating agent is initially added to the organic phase and extracted into the aqueous phase. The metal-ligand complex is...
1.2K
01:25Physiological Barriers
5.2K
Physiological barriers are semi-permeable cellular structures restricting drug diffusion into intracellular compartments and tissues. There are six types of physiological barriers: blood endothelial, cell membrane, blood-brain, blood-cerebrospinal fluid (CSF), blood-placenta, and blood-testis barriers.
The blood endothelial barrier is the most porous of these. It allows all small ionized, un-ionized, and lipophilic molecules to pass through the endothelial lining into the interstitial space...
The blood endothelial barrier is the most porous of these. It allows all small ionized, un-ionized, and lipophilic molecules to pass through the endothelial lining into the interstitial space...
5.2K
01:24The Physiology of Taste
7.7K
The perception of a salty flavor is facilitated by sodium ions within the oral salivary fluid. Upon consumption of a salty substance, salt crystals disassemble, leading to the liberation of its constituents—Na+ and Cl- ions. These ions subsequently dissolve into the salivary fluid present in the oral cavity. The external environment of the gustatory cells experiences an elevation in Na+ concentration, thereby establishing a potent concentration gradient. This gradient propels the...
7.7K