Muscle deterioration

Neuroleptic-like malignant syndrome is a serious but very rare adverse effect of some drugs, of e.g., neuroleptics, some anaesthetics and apparently tolca-pone. Symptoms include hyperthermia, muscle deterioration, even dissolution. 

The gene involved in myotonic dystrophy encodes a protein kinase whose function is still uncharacterized, The disease is characterized by progressive muscle deterioration, cardiac amhythmia, frontal baldness, cataracts, and teaicular atrophy. Because the disease shows anticipation, symptoms range ftom mild to a severe neonatal condition. 

Thi autosomal dominant disorder, which affects approximately 1 in 8,000 individuals, is characterized by progressive muscle deterioration, cardiac arrhythmia, testicular atrophy, frontal baldness, and cataraas. As noted above, most cases are caused by a trinucleotide repeat expansion in the 3 UTR of a gene that encodes a protein kinase. Larger repeat numbers lead to earlier and more severe expression of the disease (anticipation). Especially large expansions sometimes occur in maternal transmission of the trinucleotide repeat, resulting in a severe neonatal form of the disorder. 

Steroids that aid in muscle development are called anabolic steroids. They are synthetic derivatives of testosterone, thus have the same muscle-building effect as testosterone. There are more than 100 different anabolic steroids which, vary in structure, duration of action, relative effects and toxicities. Androstenedione, stanozolol and dianabol are anabolic steroids. They are used to treat people suffering from traumas accompanied by muscle deterioration. The use of anabolic steroid can lead to a number of dangerous side-effects, including lowered levels of high density lipoprotein cholesterol, which benefits the heart, and elevated levels of harmful low density lipoprotein, stimulation of prostate tumours, clotting disorders and liver problems. 

Pastoret, C., and Sebille, A., 1995, mdx mice show progressive weakness and muscle deterioration with age, J Neurol Sci, 129, pp 97-105. 

Ando, S. (1986). Studies on the food biochemical aspects of changes in chum salmon during spawning migration. Mechanisms of muscle deterioration and nuptial colouration. Memoirs of the Faculty of Fisheries, Hokkaido University 33,1-95. 

ALS, also known as motor neuron disease (MND) and Lou Gehrig s disease, is the most common of a group of disorders in which neurons in the spinal cord and brain stem deteriorate and die, resulting in weakness and muscle deterioration. 

Synthetic anabolic steroids were originally developed in the 1930s for use in treating illnesses and Injuries that involved muscle deterioration. Unfortunately, the development of these drugs led to rampant abuse by athletes and bodybuilders, even as early as the 1940s. The problem received wide public attention during the 1988 Olympics when Ben Johnson (Canada) was disqualified as the gold medal winner of the 100-meter dash because his urine tested positive for traces of stanozolol. 

The pharmaceutical industry has developed and studied a number of anabolic steroids for use in vet erinary medicine and in rehabilitation from injuries that are accompanied by deterioration of muscles The ideal agent would be one that possessed the an abolic properties of testosterone without its andro genic (masculinizing) effects Methandrostenolone (Dianabol) and stanozolol are among the many syn thetic anabolic steroids that require a prescription... 

Table 8 5 shows that each of the four common s-block ions is abundant not only in seawater but also in body fluids, where these ions play essential biochemical roles. Sodium is the most abundant cation in fluids that are outside of cells, and proper functioning of body cells requires that sodium concentrations be maintained within a narrow range. One of the main functions of the kidneys is to control the excretion of sodium. Whereas sodium cations are abundant in the fluids outside of cells, potassium cations are the most abundant ions in the fluids inside cells. The difference in ion concentration across cell walls is responsible for the generation of nerve impulses that drive muscle contraction. If the difference in potassium ion concentration across cell walls deteriorates, muscular activity, including the regular muscle contractions of the heart, can be seriously disrupted. 

Function begins to return as soon as nutritional support is introduced, even before any tissue gain, suggesting an immediate and direct effect on cellular function. Skeletal and respiratory muscle function deteriorates steeply after a loss of 20% of body protein stores (equivalent to 15% total body weight loss) and improves by 10-20% within the first few days of nutritional support. 

Kennel P, Revah F, Bohme GA, et al (2000) Riluzole prolongs survival and delays muscle strength deterioration in mice with progressive motor neuropathy (pmn). J Neurol Sci 180 55-61... 

Mecfianism of Action A prostaglandin that dilates systemic and pulmonary arterial vascular beds, alters pulmonary vascular resistance, and suppresses vascular smooth muscle proliferation. Therapeutic Effect Improves symptoms and exercise tolerance in patients with pulmonary hypertension delays deterioration of condition. Pharmacokinetics Protein binding 60%. Metabolized in liver. Primarily excreted in urine minimal elimination in feces. Half-life 20-30 min. 

Any dialogue on meat flavor development and deterioration requires a brief discussion of muscle structure. Muscle has a highly compact and complex multicellular structural organization (Figure 2). Individual muscle cells contain numerous mitochondria and nuclei. They also contain contractile elements as the bulk of their structure. While the sarcoplasm of muscle (the aqueous non-organellar component) is small compared to the cytoplasm of non-muscle cells, it does have a highly evolved system of membranes called the SR/L representing an acronym for sarcoplasmic reticulum/lysosomal membrane system (11). The SR/L surrounds each contractile element (Fig. 9-13 in 12 Fig. 7-10 in 13). The close proximity of the SR/L to the contractile proteins situates the proteins in a location that is optimal for their hydrolysis by lysosomal hydrolases (12, 13). 

The formation of free radicals after lipid oxidation is known to play a key role in the deterioration of meat flavor 8, 23), Since proteins constitute a major portion of the muscle s composition, the relationship between chemically active radical species and decomposition of food flavor proteins and peptides needs to be studied in detail. Data has been presented showing the correlation of proteins with flavor (Figures 5 and 6). Data is now presented showing how soluble meat proteins change in an environment where free radicals are induced by a free-radical oxidation generating system or FROG (Figure 10). 

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