Tired Pt II
Went down a little sciencey rabbit hole today…wondering why iron fixed so much that was wrong with me. I knew blood oxygen had something to do with it…
Hypoxia is a condition in which the body or a region of the body is deprived of adequate oxygen supply at the tissue level. Hypoxia may be classified as either generalized, affecting the whole body, or local, affecting a region of the body.
Anemic hypoxia: In this form of hypoxia, the lungs are in perfect working condition, but the oxygen carrying capacity of the blood has been reduced. As the name implies, anemia is a very effective way of producing anemic hypoxia
Anemic hypoxia occurs when the oxygen carrying ability of the blood decreases, and thus, this defect is specifically associated with the blood. This implies that fewer hemoglobin molecules (or oxygen-binding sites) are available for binding oxygen.
Hypoxia –> Depression?
There are a lot of studies.
Rates of depression and suicide are higher in people living at altitude, and in those with chronic hypoxic disorders like asthma, chronic obstructive pulmonary disorder (COPD), and smoking. Living at altitude exposes people to hypobaric hypoxia, which can lower rat brain serotonin levels, and impair brain bioenergetics in both humans and rats. We therefore examined the effect of hypobaric hypoxia on depression-like behavior in rats. After a week of housing at simulated altitudes of 20,000 ft, 10,000 ft, or sea level, or at local conditions of 4500 ft (Salt Lake City, UT), Sprague Dawley rats were tested for depression-like behavior in the forced swim test (FST). Time spent swimming, climbing, or immobile, and latency to immobility were measured. Female rats housed at altitude display more depression-like behavior in the FST, with significantly more immobility, less swimming, and lower latency to immobility than those at sea level. In contrast, males in all four altitude groups were similar in their FST behavior. Locomotor behavior in the open field test did not change with altitude, thus validating immobility in the FST as depression-like behavior. Hypobaric hypoxia exposure therefore induces depression-like behavior in female rats, but not in males.
Hypoxemia is a common complication of the diseases associated with the central nervous system, and neurons are highly sensitive to the availability of oxygen. Neuroplasticity is an important property of the neural system controlling breathing, memory, and cognitive ability. However, the underlying mechanism has not yet been clearly elucidated. In recent years, several pieces of evidence have highlighted the effect of hypoxic injury on neuronal plasticity in the pathogenesis and treatment of mood disorder.
Histogenous hypoxia is present in patients with depression and this is related to elevated venous pH; both of these are related to depression. Elevated venous pH and decreased PvCO2 may explain histogenous hypoxia in depression and venous blood gas concentrations potentially represent a biomarker for depression.
There is growing evidence from human neuroimaging, genetics, epidemiology, and animal studies that disruptions in brain energy production, storage, and utilization are implicated in the development and maintenance of depression. Creatine, a widely available nutritional supplement, has the potential to improve these disruptions in some patients, and early clinical trials indicate that it may have efficacy as an antidepressant agent.