1.
Hypotheses about sub-optimal hydration in the weeks before coronavirus disease (COVID-19) as a risk factor for dying from COVID-19.
Stookey, JD, Allu, PKR, Chabas, D, Pearce, D, Lang, F
Medical hypotheses. 2020;:110237
Abstract
To address urgent need for strategies to limit mortality from coronavirus disease 2019 (COVID-19), this review describes experimental, clinical and epidemiological evidence that suggests that chronic sub-optimal hydration in the weeks before infection might increase risk of COVID-19 mortality in multiple ways. Sub-optimal hydration is associated with key risk factors for COVID-19 mortality, including older age, male sex, race-ethnicity and chronic disease. Chronic hypertonicity, total body water deficit and/or hypovolemia cause multiple intracellular and/or physiologic adaptations that preferentially retain body water and favor positive total body water balance when challenged by infection. Via effects on serum/glucocorticoid-regulated kinase 1 (SGK1) signaling, aldosterone, tumor necrosis factor-alpha (TNF-alpha), vascular endothelial growth factor (VEGF), aquaporin 5 (AQP5) and/or Na+/K+-ATPase, chronic sub-optimal hydration in the weeks before exposure to COVID-19 may conceivably result in: greater abundance of angiotensin converting enzyme 2 (ACE2) receptors in the lung, which increases likelihood of COVID-19 infection, lung epithelial cells which are pre-set for exaggerated immune response, increased capacity for capillary leakage of fluid into the airway space, and/or reduced capacity for both passive and active transport of fluid out of the airways. The hypothesized hydration effects suggest hypotheses regarding strategies for COVID-19 risk reduction, such as public health recommendations to increase intake of drinking water, hydration screening alongside COVID-19 testing, and treatment tailored to the pre-infection hydration condition. Hydration may link risk factors and pathways in a unified mechanism for COVID-19 mortality. Attention to hydration holds potential to reduce COVID-19 mortality and disparities via at least 5 pathways simultaneously.
2.
Inspissated oral secretions and a review of their clinical, biological, and physiological significance.
Flanagan, D
Special care in dentistry : official publication of the American Association of Hospital Dentists, the Academy of Dentistry for the Handicapped, and the American Society for Geriatric Dentistry. 2012;(3):99-104
Abstract
People with some chronic diseases may dehydrate and develop thick, viscous inspissated oronasal secretions that include cellular debris. This material can lead to ductal or airway obstructions that can prove to be life threatening. Asthma, allergy with superinfection, cystic fibrosis, intubated ventilation, burn injuries, and medication-induced complications are discussed in this paper. Many patients with chronic debilitating conditions may also be unable to communicate, and so may be unable to verbally convey that they have a compromised airway or an obstruction. Therefore, it is essential to maintain hydration and good oral hygiene that not only addresses the teeth and prostheses, but also the oral mucosal surfaces. People who are institutionalized and bed-ridden, in particular, need to be closely monitored to prevent adverse sequellae. A daily oral sweep with a 4 × 4 surgical sponge moistened with chlorhexidine may prevent aspiration pneumonia or a fatality due to an airway obstruction. Human oronasal secretions are involved with immunity, digestion, lubrication, and speech. Saliva is the most volumetrically important. These secretions moisturize inspired and expired air but can lose water, causing an increase in viscosity. The viscous secretions trap particles, food debris, and bacterial colonies, thereby increasing inspissations that may obstruct the airway.
3.
Alleviating effects of dehydration under no hyperthermia on the immunomodulatory response to the polysaccharide fraction from fu-ling (Poria cocos) in male collegiate wrestlers.
Jang, TR, Kao, MF, Chen, CH, Hsieh, KC, Lai, WY, Chen, YY
Chinese medical journal. 2011;(4):530-6
Abstract
BACKGROUND It is well known that dehydration can impair bodily functions. To evaluate the impact of hydration status under ambient environmental temperature on the immune system, 25 male collegiate wrestlers were recruited to undergo an experimental dehydration program. METHODS Thirteen subjects had controlled diets with individual energy requirements to prevent body mass loss and restricted water intake to cause 4.52% dehydration; they formed the dehydrated group (DE). These subjects developed a urine specific gravity of about 1.030 in 84 hours. Twelve other subjects had no water restriction and maintained their total body weight comprised the euhydrated group (EU). Peripheral blood monocytes (PBMNC) were isolated after dehydration to perform immune response testing by being incubated with a polysaccharide fraction from fu-ling, Poria cocos (polysaccharide fraction from Poria cocos, PCPS, 1 - 30 £g/L), to prepare a conditioned medium termed conditioned medium of PBMNC stimulated by PCPS (PCPS-MNC-CM). More PCPS (25 µg/L) was needed in the DE group to prepare the PCPS-MNC-CM, which was assayed with a growth inhibitory curve for treated U973 cells. RESULTS The treated U937 cells, incubated together with PCPS-MNC-CM from the DE group, exhibited a much lower nitroblue tetrazolium (NBT) positive value of (63.7 ± 4.7)%. The concentration of interferon-gamma (IFN-γ), interleukin (IL)-1β and tumor necrosis factor (TNF)-α in PCPS-MNC-CM from subjects after dehydration was much lower than in the CM from the EU group. CONCLUSION The immune response to PCPS in the DE group was lower than in normally hydrated subjects.