The effect of scurvy on glycosaminoglycans of granulation tissue and costal cartilage

Learning the oral and cutaneous signs of micronutrient deficiencies

Wound healing is a complex process that is influenced by multiple systemic factors, including nutritional status. While nutritional support is commonly recognized as an important aspect of comprehensive wound management, the focus is typically on replacement of macronutrients, specifically calories and protein. Our experience strongly suggests that micronutrients are equally important, that micronutrient deficiencies are common, and that correction of these deficiencies frequently leads to wound healing when incorporated into a comprehensive wound management program. This article provides guidelines for assessment and management of micronutrient deficiencies.

Coordinate regulation of collagen and proteoglycan synthesis in costal cartilage of scorbutic and acutely fasted, vitamin C-supplemented guinea pigs

The effects of ascorbic acid deficiency and acute fasting (with ascorbate supplementation) on the synthesis of collagen and proteoglycan in costal cartilages from young guinea pigs was determined by in vitro labeling of these components with radioactive proline and sulfate, respectively. Both parameters were coordinately decreased by the second week on a vitamin C-free diet, with a continued decline to 20-30% of control values by the fourth week. These effects were quite specific, since incorporation of proline into noncollagenous protein was reduced by only 30% after 4 weeks on the deficient diet. The time course of the decrease in collagen and proteoglycan synthesis paralleled the loss of body weight induced by ascorbate deficiency. Hydroxylation of proline in collagen synthesized by scorbutic costal cartilage was reduced to about 60% of normal relatively early, and remained at that level thereafter. Neither collagen nor proteoglycan synthesis was returned to normal by the addition of ascorbate (0.2 mM) to cartilage in vitro. Administration of a single dose of ascorbate to scorbutic guinea pigs increased liver ascorbate and restored proline hydroxylation to normal levels by 24 h, but failed to increase the synthesis of collagen or proteoglycan. Synthesis of both extracellular matrix components was restored to control levels after four daily doses of ascorbate. A 96-h total fast, with ascorbate supplementation, produced rates of weight loss and decreases in the synthesis of these two components similar to those produced by acute scurvy. There was a linear correlation between changes in collagen and proteoglycan synthesis and changes in body weight during acute fasting, scurvy, and its reversal. These results suggest that it is the fasting state induced by ascorbate deficiency, rather than a direct action of the vitamin in either of these two biosynthetic pathways, which is the primary regulatory factor.

Cutaneous tissue repair: practical implications of current knowledge. II

This article reviews the scientific basis for the certain factors that delay wound repair in the clinical setting. A brief history of wound healing is given, followed by a discussion of endogenous local factors (bacterial infection, hypoxia, foreign body, and desiccation) and endogenous systemic factors (nutritional deficiencies, aging, coagulation disorders, and the Ehlers-Danlos syndromes) associated with poor wound repair. Also reviewed are the mechanisms by which exogenously administered agents (glucocorticoids, antineoplastic agents, and anticoagulants) may delay healing. Commonly used topical antimicrobials, their spectrum of activity, and evidence of effects on wound healing are examined. Finally, properties of commercially available wound coverings and wound care in the future are discussed.

The effect of intestinal coccidiosis (Eimeria acervulina) on blood and tissue ascorbic acid concentrations

1. Two experiments were conducted to investigate the effect of intestinal coccidiosis (Eimeria acervulina) on blood plasma and tissue ascorbic acid (AA) concentrations in chicks, and a third experiment was carried out to examine the role of dietary AA in this infection. 2. Experimental infection with intestinal coccidiosis (Eimeria acervulina) brought about a depletion in the concentration of AA in blood plasma, duodenum, jejunum, ileum, liver and the adrenal glands. Generally, these changes were obtained after the prepatent period of 4-5 d of the infection. 3. Dietary AA at 1000 mg/kg prevented the depletion in plasma and tissue AA levels but did not significantly affect adrenal weight.

The effect of scurvy on hexosamine-containing substances in healing wounds in guinea pigs

1. Granulation tissue from healing tendonectomy wounds in guinea pigs was analysed and the effects of inanition and ascorbic acid deficiency on this tissue were investigated. 2. Inanition produced no significant effect on either the glucosamine or the galactosamine content of the tissue. Ascorbic acid deficiency decreased the galactosamine content without affecting the glucosamine content. 3. Fractionation of papain-digested granulation tissue gave three major fractions, which behaved respectively as glycopeptide, hyaluronic acid and a sulphated glycosaminoglycan mixture. At least half of the sulphated glycosaminoglycan mixture behaved as dermatan sulphate. 4. Inanition produced no consistent effect on the fractions examined. In ascorbic acid deficiency, a decrease in the sulphated glycosaminoglycan fraction was observed, which accounted for the decreased galactosamine content of the tissue. This was accompanied by a decrease in hyaluronic acid and a slight increase in the glycopeptide fraction.