elastin and Nutrition-Disorders

Topics: Aerosols; alpha 1-Antitrypsin Deficiency; Animals; Blood Platelets; Cadmium; Collagen; Disease Models, Animal; Elastin; Emphysema; Forecasting; Hexanes; Lathyrism; Macrophages; Mice; Mice, Mutant Strains; Microscopy, Electron; Neutrophils; Nutrition Disorders; Oxygen; Pancreatic Elastase; Papain; Physical Exertion; Pulmonary Fibrosis; Pulmonary Gas Exchange; Pulmonary Heart Disease; Respiration; Trypsin

Topics: Catalase; Connective Tissue; Elastin; Emphysema; Free Radicals; Humans; Lung; Lung Injury; Macrophages; Monocytes; Neutrophils; Nutrition Disorders; Nutritional Physiological Phenomena; Pancreatic Elastase; Protease Inhibitors; Protein Biosynthesis; Superoxide Dismutase

Topics: Amino Acid Sequence; Amino Acids; Aminopropionitrile; Animals; Chemical Phenomena; Chemistry; Collagen; Copper; Desmosine; Elastin; Humans; Hydroxylysine; Lysine; Metabolism, Inborn Errors; Nutrition Disorders; Nutritional Physiological Phenomena; Penicillamine; Protein-Lysine 6-Oxidase; Tropocollagen

Topics: Amino Acids; Animals; Child; Collagen; Connective Tissue; Copper; Deficiency Diseases; Elastin; Humans; Iron; Nutrition Disorders; Nutritional Physiological Phenomena; Pellagra; Protein Precursors; Protein-Energy Malnutrition; Rats; Scurvy; Skin

Prolonged hyperoxic exposure is associated with impaired alveolarization of the lung in both the rat and the human neonate. Elastin is currently thought to play a pivotal role in the alveolarization of the lung by providing the structural framework around which new alveoli will develop. Previous studies in both the rat and the human neonate have demonstrated a risk for proteolytic destruction of lung elastin associated with prolonged hyperoxic exposure. The present study was undertaken to determine whether continuous exposure to 100% oxygen during the period of alveolar development in the rat (Days 4 to 13) would alter lung elastin. Parenchymal lung elastic fiber length, volume density of parenchyma, mean linear intercept, and internal surface area were quantitated using morphometric techniques, and the values were compared in control, oxygen-exposed, and malnourished rat pups. Stereologic measurements indicated that total elastic fiber length was significantly greater in lungs of control pups than in lungs of either the oxygen-exposed or the malnourished pups. Examination of sections of lung tissue 20 to 30 microns thick indicated altered elastic fiber structure and numerous alveolar fenestrae only in the hyperoxic pups. The results of these studies demonstrated that hyperoxic exposure during alveolarization alters both total length and structure of lung elastic fibers and suggest that impaired lung development might be due in part to these observed changes.

Topics: Animals; Animals, Newborn; Elastic Tissue; Elastin; Female; Histological Techniques; Lung; Male; Nutrition Disorders; Oxygen; Pulmonary Alveoli; Rats; Rats, Inbred Strains; Weight Gain

In vivo lung connective tissue and DNA synthesis, following intraperitoneal injection of [14C]proline and [3H]thymidine, were studied in streptozotocin-induced diabetic rats fed ad libitum. Insulin-treated diabetic and normal rats similarly fed, and undernourished rats weight-matched to the untreated diabetics, served as comparison groups. The ratio of unbound [14C]hydroxyproline to total [14C]hydroxyproline in the lung was used to assess connective tissue degradation. Compared to the normal group, the untreated diabetic animals showed similar synthesis of collagen and elastin, reduced synthesis of total protein and DNA, and decreased degradation of connective tissue. When compared with the normal group, the undernourished animals showed diminished synthesis of total protein, collagen, elastin, and DNA, and increased degradation of connective tissue. In comparison to the undernourished group, the untreated diabetic animals indicated increased synthesis of collagen and elastin, and diminished degradation of connective tissue; total protein and DNA syntheses were similar. The insulin-treated diabetic animals showed increased collagen and DNA synthesis. We conclude that experimental diabetes has a profound effect on lung connective tissue metabolism, supporting previous observations of connective tissue abnormalities and morphometric changes. The increase in lung collagen and elastin in diabetes is in part due to reduced breakdown of the connective tissue proteins.

Topics: Animals; Collagen; Connective Tissue; Diabetes Mellitus, Experimental; DNA; Elastin; Hydroxyproline; Insulin; Lung; Male; Nutrition Disorders; Proline; Protein Biosynthesis; Rats; Rats, Inbred Strains; Thymidine

Diabetes induced by streptozotocin at 3 wk of age in rats resulted in diminished somatic growth by 7 wk of age. Specific lung volume and weight (volume or weight per 100 gram body weight) were increased. The amount of lung DNA was decreased, and collagen and elastin were increased. The volume proportion of alveolar walls was increased at the expense of alveolar air. Air spaces were diminished in size, and alveoli increased in number. Total phospholipids and disaturated phosphatidylcholine (DSPC) were decreased, but they were normal relative to alveolar surface area. These changes reverted towards normal as a result of insulin treatment. Rats matched in weight (undernourished animals) for the diabetic animals showed relative preservation of lung weight, increased DNA, and reduced nonconnective tissue protein, RNA, collagen, and elastin. Air spaces were enlarged, alveolar surface area was decreased, and alveoli were decreased in number. Total phospholipids and DSPC were decreased, but normal when expressed per alveolar surface area. We conclude that diabetes and undernourishment have different effects on connective tissue synthesis in the lung that affect lung growth and structure, providing further evidence for the "fishnet" hypothesis of alveolar growth.

Topics: Animals; Collagen; Diabetes Mellitus, Experimental; DNA; Elastin; Lung; Nutrition Disorders; Organ Size; Phosphatidylcholines; Phospholipids; Pulmonary Alveoli; Rats; Rats, Inbred Strains

Topics: Animals; Arteries; Coronary Vessels; Elastic Tissue; Elastin; Nutrition Disorders; Pancreatic Elastase; Sodium Chloride; Solubility; Swine; Water