Breaking News
January 19, 2019 - Highly effective protocol to prepare cannabis samples for THC/CBD analysis
January 19, 2019 - Prinston Pharmaceutical Inc. Issues Voluntary Nationwide Recall of Irbesartan and Irbesartan HCTZ Tablets Due to Detection of a Trace Amount of Unexpected Impurity, N-Nitrosodiethylamine (NDEA) in the Products
January 19, 2019 - How does solid stress from brain tumors cause neuronal loss, neurologic dysfunction?
January 19, 2019 - $14.7 million partnership to supercharge vaccine development
January 19, 2019 - Ian Fotheringham receives Charles Tennant Memorial Lecture award
January 19, 2019 - Brain vital signs detect neurophysiological impairments in players with concussions
January 19, 2019 - Lack of job and poor housing conditions increased likelihood of people attending A&E
January 19, 2019 - Novel targeted drug delivery system improves conventional cancer treatments
January 19, 2019 - Rutgers study finds gene responsible for spread of prostate cancer
January 19, 2019 - Complications Higher Than Expected for Invasive Lung Tests
January 19, 2019 - 3-D printed implant promotes nerve cell growth to treat spinal cord injury
January 19, 2019 - Automated texts lead to improved outcomes after total knee or hip replacement surgery
January 19, 2019 - Poor cardiorespiratory fitness could increase risk of future heart attack, finds new study
January 19, 2019 - Drinking soft drinks while exercising in hot weather may increase risk of kidney disease
January 19, 2019 - Formlabs 3D prints anatomical models
January 19, 2019 - Heart-Healthy Living Also Wards Off Type 2 Diabetes
January 19, 2019 - Teaching Kids to Be Smart About Social Media (for Parents)
January 19, 2019 - Metabolite produced by gut microbiota from pomegranates reduces inflammatory bowel disease
January 19, 2019 - Researchers examine how spray from showers and toilets expose us to disease causing bacteria
January 19, 2019 - Behavioral experiments confirm that additional neurons improve brain function
January 19, 2019 - New study compares performance of real-time infectious disease forecasting models
January 19, 2019 - Obesity can be risk factor for developing renal cell carcinoma, confirms study
January 19, 2019 - New regulation designs on cigarette packs direct smokers’ attention to health warnings
January 19, 2019 - QIAGEN receives first companion diagnostic approval in Japan
January 19, 2019 - Study explores role of Dunning-Kruger effect in anti-vaccine attitudes
January 19, 2019 - Newly identified subset of immune cells may be key to fighting chronic inflammation
January 19, 2019 - New immune response regulators discovered
January 18, 2019 - Poor blood oxygenation during sleep predicts chance of heart-related death
January 18, 2019 - First international consensus on the diagnosis and management of fibromuscular dysplasia
January 18, 2019 - Rapid resistance gene sequencing technology can hasten identification of antibiotic-resistant bacteria
January 18, 2019 - Researchers develop artificial enzymatic pathway for synthesizing isoprenoids in E. coli
January 18, 2019 - Scientists advise caution in immunotherapy research
January 18, 2019 - How children across the world develop language
January 18, 2019 - Columbia Medical Student Receives McDonogh Scholarship
January 18, 2019 - Secretive ‘Rebate Trap’ Keeps Generic Drugs For Diabetes And Other Ills Out Of Reach
January 18, 2019 - Plant based diet could be the best option for the planet says commission
January 18, 2019 - New conservation practice could reduce nitrogen from agricultural drainage, study shows
January 18, 2019 - UIC researchers receive $1.7 million NCI grant to study Southeast Asian fruit
January 18, 2019 - New study determines the fate of DNA derived from genetically modified food
January 18, 2019 - Scientists develop new gene therapy that prevents axon destruction in mice
January 18, 2019 - Study finds critically low HPV vaccination rates among younger adolescents in the U.S.
January 18, 2019 - Brain cells involved in memory play key role in reducing future eating behavior
January 18, 2019 - Risk for Conversion of MS Varies With Different Therapies
January 18, 2019 - Investigational cream may help patients with inflammatory skin disease
January 18, 2019 - Medical school news office receives six writing awards | News Center
January 18, 2019 - County By County, Researchers Link Opioid Deaths To Drugmakers’ Marketing
January 18, 2019 - Research reveals risk for developing more than one mental health disorder
January 18, 2019 - Scientists discover a dramatic pattern of bone growth in female mice
January 18, 2019 - Study finds link between lengthy periods of undisturbed maternal sleep and stillbirths
January 18, 2019 - New nuclear medicine method could improve detection of primary and metastatic melanoma
January 18, 2019 - Combination therapy shows high efficacy in treating people with leishmaniasis and HIV
January 18, 2019 - Health Tip: Don’t Ignore Changes in Skin Color
January 18, 2019 - Dietary Recommendations for Healthy Children
January 18, 2019 - Eliminating the latent reservoir of HIV
January 18, 2019 - Pain From The Government Shutdown Spreads. This Time It’s Food Stamps
January 18, 2019 - Newly discovered regulatory mechanism helps control fat metabolism
January 18, 2019 - New rapid blood tests could speed up TB diagnosis, save the NHS money
January 18, 2019 - Researchers develop intelligent system for ‘tuning’ powered prosthetic knees
January 18, 2019 - Monoclonal antibody pembrolizumab prolongs survival in patients with squamous cell carcinoma
January 18, 2019 - New research detects mosquito known to transmit malaria for the first time in Ethiopia
January 18, 2019 - Researchers identify new genes linked to development of age-related macular degeneration
January 18, 2019 - Computerized method helps better protect pharma patents
January 18, 2019 - New guidelines to make swallowing safer for people in Australian nursing homes
January 18, 2019 - Lumex Instruments’ RA-915AM monitor installed at Hg treatment plant in Almadén, Spain
January 18, 2019 - ACCC survey finds multiple threats to growth of cancer programs
January 18, 2019 - Meeting the challenge of engaging men in HIV prevention and treatment
January 18, 2019 - Furloughed Feds’ Health Coverage Intact, But Shutdown Still Complicates Things
January 18, 2019 - Experts discuss various aspects on health risks posed by fumigated containers
January 18, 2019 - Researchers use gene-editing tool CRISPR/Cas9 to limit impact of parasitic diseases
January 18, 2019 - Alpha neurofeedback training could be a means of enhancing learning success
January 18, 2019 - Innovative ‘light’ method demonstrates positive results in fight against malignant tumors
January 18, 2019 - The cytoskeleton of neurons found to play role in Alzheimer’s disease
January 18, 2019 - New resource-based approach to improve HIV care in low- and middle-income countries
January 18, 2019 - Bedfont appoints Dr Jafar Jafari as first member of the Gastrolyzer Medical Advisory Board
January 18, 2019 - New study shows link between secondhand smoke and cardiac arrhythmia
January 18, 2019 - DZIF scientists reveal problems with available diagnostics for Zika and chikungunya virus
January 18, 2019 - Breast cancers more likely to metastasize in young women within 10 years of giving birth
January 18, 2019 - Over 5.6 million Americans exposed to high nitrate levels in drinking water
January 18, 2019 - Blood vessels can now be created perfectly in a petri dish
January 18, 2019 - Study identifies prominent socioeconomic and racial disparities in health behavior in Indiana
Inactivity of astronauts during spaceflights may have more pronounced effect on skeletal muscle than hypoxia

Inactivity of astronauts during spaceflights may have more pronounced effect on skeletal muscle than hypoxia

image_pdfDownload PDFimage_print

The inactivity of astronauts during spaceflights presents a significant risk to their muscles, says a new study in The Journal of Physiology. Scientists have simulated the impact of 21 day spaceflights on the body, and the impact of low gravity environments such as the Moon or Mars.

During spaceflights, and in future habitats on the Moon or Mars, humans are or will be exposed to a condition of “microgravity”, in other words to a gravitational field much smaller compared to that present on Earth. This environmental stress has negative consequences on many organs, systems and functions of the body, including bone, muscle, plus the cardiovascular, respiratory and nervous systems. Spaceflights and reduced gravity habitats will expose astronauts also to low oxygen environments. The hypoxic stress will therefore be superimposed upon that related to reduced gravity.

Mitochondria are found in cells and they use oxygen to produce energy in a process called oxidative metabolism. People use their skeletal muscles for movement, and therefore to be active requires oxidative metabolism by these muscles. The muscles need for oxygen led researchers to think that the low oxygen (“hypoxic”) environments of spaceflight or future planetary worlds would impair function. However, they found that inactivity itself may have a more pronounced effect on skeletal muscle than a lack of oxygen.  

The results demonstrated that the impairments following microgravity were not aggravated by hypoxia. Given that inactivity and hypoxia are frequently associated with several important cardiovascular and respiratory diseases there is a suggestion that for skeletal muscle, inactivity is worse compared to hypoxia.  If confirmed, this finding would have obvious relevant consequences on therapeutic and rehabilitative interventions: correction of hypoxia could be less critical than correction of inactivity.

As well as for astronauts, this research could have a significant impact in patients with chronic diseases characterized by immobility and hypoxia.

The study led by physiologists from the University of Udine was carried out in conjunction with University of Pavia, Trieste, the Milano Polytechnic, University of Munich, Nottingham, German Aerospace Center, Swedish Aerospace Physiology Centre, Jožef Stefan Institute from Ljubljana, Slovenia (Coordinator of the Study) and Simon Fraser University, Burnaby. The researchers evaluated the mechanisms by which the tissue obtains energy by burning sugars and fats by the intervention of oxygen during exercise, on the knee extensors of one leg in 11 active men. Mitochondrial respiration was also evaluated on skeletal muscle fibers by biopsy.

It is important to note that another study from the research group (the PlanHab Project), looking at whole-body exercise, found that hypoxia did in fact aggravate the impairment caused by microgravity alone. This suggests that the effects of hypoxia could be more significant during whole body exercise, in which the stress on the cardiovascular system is more pronounced.

Bruno Grassi, the chief investigator on the project said:

This research will help prepare astronauts for spaceflight and it improves our understanding of how muscles respond to long periods of inactivity in association with hypoxia.

Future studies will have to investigate in more detail the mechanisms responsible for the observed findings. The results obtained on skeletal muscles, moreover, will have to be interpreted in conjunction with those deriving from other studies of the PlanHab project, dealing with the cardiovascular, respiratory, immune and central nervous systems and metabolism.

About author

Related Articles