Läskeblask försämrar vätskebalansen och förvärrar njurskador vid uttorkning

[King Grub]

Recurrent dehydration, such as commonly occurs with manual labor in tropical environments, has been recently shown to result in chronic kidney injury, likely through the effects of hyperosmolarity to activate both vasopressin and aldose reductase-fructokinase pathways. The observation that the latter pathway can be directly engaged by simple sugars (glucose and fructose) leads to the hypothesis that soft drinks (which contain these sugars) might worsen rather than benefit dehydration associated kidney disease. Recurrent dehydration was induced in rats by exposure to heat (36°C) for 1 h/24 h followed by access for 2 h to plain water (W), a 11% fructose-glucose solution (FG, same composition as typical soft drinks), or water sweetened with noncaloric stevia (ST). After 4 wk plasma and urine samples were collected, and kidneys were examined for oxidative stress, inflammation, and injury. Recurrent heat-induced dehydration with ad libitum water repletion resulted in plasma and urinary hyperosmolarity with stimulation of the vasopressin (copeptin) levels and resulted in mild tubular injury and renal oxidative stress. Rehydration with 11% FG solution, despite larger total fluid intake, resulted in greater dehydration (higher osmolarity and copeptin levels) and worse renal injury, with activation of aldose reductase and fructokinase, whereas rehydration with stevia water had opposite effects. In animals that are dehydrated, rehydration acutely with soft drinks worsens dehydration and exacerbates dehydration associated renal damage. These studies emphasize the danger of drinking soft drink-like beverages as an attempt to rehydrate following dehydration.

Rehydration with soft drink-like beverages exacerbates dehydration and worsens dehydration-associated renal injury. American Journal of Physiology - Regulatory, Integrative and Comparative Physiology 1 July 2016 Vol. 311 no. 1, R57-R65.

http://ajpregu.physiology.org/content/311/1/R57.full.pdf+html

[Pepz]

intressant.

är det just mängden enkla sockerarter som är det problematiska?

[Sverker]

Hur förklarar man detta:confused:.

Fick råttorna högre blodsocker som gav högre blodtryck över njurarna och mer skador på njurarna ( klassisk diabetesskada ) ?

[Luca Brasi]

Hur förklarar man detta:confused:.

Fick råttorna högre blodsocker som gav högre blodtryck över njurarna och mer skador på njurarna ( klassisk diabetesskada ) ?
Nä.
Resten,- ja men som följd av uttorkning på grund av att läsken är en usel för rehydrering, ungefär?

The present study shows that short-term rehydration with a FG sugary beverage after a mild dehydration stimulates the two systems that have been implicated in kidney injury, i.e., vasopressin (1) and aldose reductase-fructokinase activities (34). After rehydration with a fructose-rich beverage, we observed a greater renal oxidative stress and mild renal injury (glomerular and tubular alterations). In contrast, rehydration with plain water or with the noncaloric edulcorant stevia did not produce such deleterious effects.

Fructose is a substrate for fructokinase that is present in the proximal tubule, and a 60% fructose diet in rats can induce modest tubular injury (11, 28). Fructose infusion in humans can also stimulate vasopressin release, whereas an equimolar solution of glucose does not (42). Our basic hypothesis was that recurrent stimulation of these pathways might induce renal disease and that hydration with fructose-containing solutions could increase vasopressin release and provide a substrate for fructokinase that might lead to further renal damage.

[Sverker]

Men då är det lugnt för oss ickegnagare. Vi ska inte få ut fruktos i blodet. Den ska stoppas i levern och omsättas där.

Fruktos är alldeles för reaktivt för att tillåtas cirkulera i blodet.