"Creatine: More than a sports nutrition supplement"
Creatine and neuromuscular diseases
One of the most promising areas of research with creatine is its effect on neuromuscular diseases such as MD. One study looked at the safety and efficacy of creatine monohydrate in various types of muscular dystrophies using a double blind, crossover trial. Thirty-six patients (12 patients with facioscapulohumeral dystrophy, 10 patients with Becker dystrophy, eight patients with Duchenne dystrophy and six patients with sarcoglycan-deficient limb girdle muscular dystrophy) were randomized to receive creatine or placebo for eight weeks. The researchers found there was a "mild but significant improvement" in muscle strength in all groups. The study also found a general improvement in the patients' daily-life activities as demonstrated by improved scores in the Medical Research Council scales and the Neuromuscular Symptom scale. Creatine was well tolerated throughout the study period, according to the researchers.1
Another group of researchers fed creatine monohydrate to people with neuromuscular disease at 10 grams per day for five days, then reduced the dose to 5 grams per day for five days. The first study used 81 people and was followed by a single-blinded study of 21 people. In both studies, body weight, handgrip, dorsiflexion and knee extensor strength were measured before and after treatment. The researchers found "Creatine administration increased all measured indices in both studies." Short-term creatine monohydrate increased high-intensity strength significantly in patients with neuromuscular disease.2 There have also been many clinical observations by physicians that creatine improves the strength, functionality and symptomology of people with various diseases of the neuromuscular system.
Creatine and neurological protection/brain injury
If there is one place creatine really shines, it's in protecting the brain from various forms of neurological injury and stress. A growing number of studies have found that creatine can protect the brain from neurotoxic agents, certain forms of injury and other insults. Several in vitro studies found that neurons exposed to either glutamate or beta-amyloid (both highly toxic to neurons and involved in various neurological diseases) were protected when exposed to creatine.3 The researchers hypothesized that "� cells supplemented with the precursor creatine make more phosphocreatine (PCr) and create larger energy reserves with consequent neuroprotection against stressors."
More recent studies, in vitro and in vivo in animals, have found creatine to be highly neuroprotective against other neurotoxic agents such as N-methyl-D-aspartate (NMDA) and malonate.4 Another study found that feeding rats creatine helped protect them against tetrahydropyridine (MPTP), which produces parkinsonism in animals through impaired energy production. The results were impressive enough for these researchers to conclude, "These results further implicate metabolic dysfunction in MPTP neurotoxicity and suggest a novel therapeutic approach, which may have applicability in Parkinson's disease."5 Other studies have found creatine protected neurons from ischemic (low oxygen) damage as is often seen after strokes or injuries.6
Yet more studies have found creatine may play a therapeutic and or protective role in Huntington's disease7, 8 as well as ALS (amyotrophic lateral sclerosis).9 This study found that "� oral administration of creatine produced a dose-dependent improvement in motor performance and extended survival in G93A transgenic mice, and it protected mice from loss of both motor neurons and substantia nigra neurons at 120 days of age. Creatine administration protected G93A transgenic mice from increases in biochemical indices of oxidative damage. Therefore, creatine administration may be a new therapeutic strategy for ALS." Amazingly, this is only the tip of the iceberg showing creatine may have therapeutic uses for a wide range of neurological disease as well as injuries to the brain. One researcher who has looked at the effects of creatine commented, "This food supplement may provide clues to the mechanisms responsible for neuronal loss after traumatic brain injury and may find use as a neuroprotective agent against acute and delayed neurodegenerative processes."
Creatine and heart function
Because it is known that heart cells are dependent on adequate levels of ATP to function properly, and that cardiac creatine levels are depressed in chronic heart failure, researchers have looked at supplemental creatine to improve heart function and overall symptomology in certain forms of heart disease. It is well known that people suffering from chronic heart failure have limited endurance, strength and tire easily, which greatly limits their ability to function in everyday life. Using a double blind, placebo-controlled design, 17 patients aged 43 to 70 years with an ejection fraction <40 were supplemented with 20 grams of creatine daily for 10 days. Before and after creatine supplementation, the researchers looked at:
1) Ejection fraction of the heart (blood present in the ventricle at the end of diastole and expelled during the contraction of the heart)
2) 1-legged knee extensor (which tests strength)
3) Exercise performance on the cycle ergometer (which tests endurance)
|
