NCT01183299

Brief Summary

The Salty Life 7 study aimed to examine the effect of a high salt (sodium chloride, NaCl) intake on different forms of sodium retention, acid-base balance and bone metabolism and other influenced physiological systems. Because of the fact that astronauts are a vulnerable group in this context, they were of special interest. Astronauts have a high salt intake, probably because of a reduced sense of taste, as well as an increased bone resorption resulting from the lowered mechanical load in space. In which forms sodium could be retained even without fluid retention (osmotically inactive)- contrary to the argumentation of physiological text books - and if the acid-base balance is connected to sodium chloride induced bone loss is examined in a stationary bed rest study with 8 healthy, young, male test subjects. The study consisting of 2 x 21 days is carried out at the German Aerospace Center (DLR). After an adaptation period of 4 days, test subjects are immobilised in 6° head-down tilt bed rest (simulation model for some physiological changes in space) for 14 days during which they received a high (7.7 mmol NaCl/kgBW/d) and a low salt (0.7 mmol NaCl/kgBW/d) intake in cross-over design. The form of sodium retention is investigated by the calculation of daily metabolic sodium-, water- and potassium balances and by changes in body weight. The measurements of bone formation (bAP, PINP, Osteocalcin) markers as well as bone resorption markers (CTX, NTX) supply insight into the influences of a high salt intake on bone metabolism. Blood gas analysis and ph values of 24-h urine are used to gather information about accompanying changes in the acid-base balance. Further physiological systems like energy metabolism and circulation system are also under investigation.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
8

participants targeted

Target at below P25 for not_applicable

Timeline
Completed

Started Apr 2005

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

April 1, 2005

Completed
1 year until next milestone

Study Completion

Last participant's last visit for all outcomes

April 1, 2006

Completed
4.2 years until next milestone

First Submitted

Initial submission to the registry

June 17, 2010

Completed
2 months until next milestone

First Posted

Study publicly available on registry

August 17, 2010

Completed
Last Updated

July 8, 2011

Status Verified

July 1, 2011

First QC Date

June 17, 2010

Last Update Submit

July 7, 2011

Conditions

Bone MetabolismElectrolyte MetabolismAcid-Base MetabolismEnergy MetabolismCirculation System

Keywords

bone metabolismsalt intakeacid base balancebed rest

Outcome Measures

Primary Outcomes (1)

  • To determine the effect of salt intake on bone metabolism in bed rest

    after 14 days of high and low salt intake

Secondary Outcomes (4)

  • To determine the effect of salt intake on acid base metabolism in bed rest

    after 14 days of high and low salt intake

  • To determine the effect of salt intake on electrolyte metabolism in bed rest

    after 14 days of high and low salt intake

  • To determine the effect of salt intake on the circulation system in bed rest

    after 14 days of high and low salt intake

  • To determine the effect of salt intake on energy metabolism in bed rest

    after 14 days of high and low salt intake

Study Arms (2)

High salt intake

ACTIVE COMPARATOR
Other: Dietary salt intake

Low salt intake

PLACEBO COMPARATOR
Other: Dietary salt intake

Interventions

Dietary salt intakeOTHER
High salt intakeLow salt intake

Eligibility Criteria

Age20 Years - 35 Years
Sexmale
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • Male
  • Age: 20-35 years
  • Weight: 65±85kg
  • Height:180±10cm.
  • Successfully completed medical \& psychological screening

You may not qualify if:

  • Drugs- and alcohol abuse
  • Hyperlipidemia
  • Obesity
  • Renal diseases
  • Participant of another study in the same time frame and 3 months before starting the study
  • Blood donation within the last three months before starting the study
  • Risk for thrombosis
  • Smoking
  • Diabetes
  • Rheumatism
  • Bone Fracture

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

German Aerospace Center

Cologne, North Rhine-Westphalia, 51147, Germany

Location

Related Publications (1)

  • Rucci N, Capulli M, Piperni SG, Cappariello A, Lau P, Frings-Meuthen P, Heer M, Teti A. Lipocalin 2: a new mechanoresponding gene regulating bone homeostasis. J Bone Miner Res. 2015 Feb;30(2):357-68. doi: 10.1002/jbmr.2341.

    PMID: 25112732DERIVED

Study Officials

  • Francisca May, Dr

    German Aerospace Center (DLR)

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
NONE
Purpose
BASIC SCIENCE
Intervention Model
CROSSOVER
Sponsor Type
OTHER

Study Record Dates

First Submitted

June 17, 2010

First Posted

August 17, 2010

Study Start

April 1, 2005

Study Completion

April 1, 2006

Last Updated

July 8, 2011

Record last verified: 2011-07

Locations

DE(1)