Sex differences in amino acids lost via sweating could lead to differential susceptibilities to disturbances in nitrogen balance and collagen turnover

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https://link.springer.com/article/10.1007/s00726-017-2431-4

Amino Acids. 2017 Aug;49(8):1337-1345. doi: 10.1007/s00726-017-2431-4. Epub 2017 May 4.
Sex differences in amino acids lost via sweating could lead to differential susceptibilities to disturbances in nitrogen balance and collagen turnover.
Dunstan RH1, Sparkes DL2, Dascombe BJ3, Stevens CJ4, Murphy GR2, Macdonald MM2, Gottfries J5, Gottfries CG6, Roberts TK2.
Author information
1
University of Newcastle, Callaghan, NSW, 2308, Australia. hugh.dunstan@newcastle.edu.au.
2
University of Newcastle, Callaghan, NSW, 2308, Australia.
3
Latrobe University, Melbourne, VIC, 3086, Australia.
4
Southern Cross University, Coffs Harbour, NSW, 2450, Australia.
5
University of Gothenburg, Box 100, 405 30, Gothenburg, Sweden.
6
Gottfries Clinic, Mölndal, Sweden.

Abstract

Fluid collected during sweating is enriched with amino acids derived from the skin's natural moisturising factors and has been termed "faux" sweat.

Little is known about sex differences in sweat amino acid composition or whether faux sweat amino acid losses affect nitrogen balance.

Faux sweat collected by healthy adults (n = 47) after exercise, and at rest by chronic fatigue patients, was analysed for amino acid composition.

Healthy females had higher total amino acid concentrations in sweat (10.5 ± 1.2 mM) compared with healthy males (6.9 ± 0.9 mM).

Females had higher levels of 13 amino acids in sweat including serine, alanine and glycine.

Higher hydroxyproline and proline levels suggested greater collagen turnover in females. Modelling indicated that with conservative levels of exercise, amino acid losses in females via faux sweat were triple than those predicted for urine, whereas in males they were double.

It was concluded that females were more susceptible to key amino acid loss during exercise and/or hot conditions.

Females reporting chronic fatigue had higher levels of methionine in faux sweat than healthy females.

Males reporting chronic fatigue had higher levels of numerous amino acids in faux sweat compared to healthy males.

Higher amino acid loss in faux sweat associated with chronic fatigue could contribute to a hypometabolic state.

Depending on activity levels, climatic conditions and gender, amino acid losses in sweat and skin leachate could influence daily protein turnover where periods of continuously high turnover could lead to a negative net nitrogen balance.

KEYWORDS:
Amino acid; Chronic fatigue; Faux sweat; Histidine; Protein turnover; Urine

PMID:

28474126

PMCID:

PMC5508033

DOI:

10.1007/s00726-017-2431-4

 

Very confusing. "Fluid collected...has been termed "faux" sweat." What's real sweat then?

In many situations it doesn't say whether people had CFS or not.

Only had a quick look.

 

Interesting. I wonder how hot flashes/night sweats fit into amino acid loss? I probably lose about 2 litres a night!

 

I am now so pumped up and full of hormones, that hot flashes are simply a thing of the past.

I don’t miss the sweaty palms, that once slid down my keyboard, nor the soaked sheets I would wake up in.

 

Selection of CFS group seems lax to me, but interesting that their findings seem consistent with Naviaux's hypometabolic study.

Would this be worth repeating with larger groups and more careful CFS selection/same criteria as Naviaux?