An early phase of wound healing involves an inflammatory response in which inflammatory cells migrate into wound sites. Neutrophils first move into the wound to defend against invading bacteria. After neutrophils kill invading organisms via free radical
Energy Expenditure Equations for Healthy Individuals
H = height (cm) W = actual weight (kg) A = age (years)
Use with activity factors: Mild: RMR x 1.1 Moderate: RMR x 1.2 - 1.3 Intense: RMR x 1.4 - 1.5
IJEE = kcal/day A = age (years) W = actual weight (kg) O = obesity (if present = 1, absent = 0)
No additional factor is added for activity or injury.
release and the secretion of proinflammatory cytokines, macrophages move into the wound (29). These cells also secrete cytokines, chemokines, and growth factors and control leukocyte recruitment. During all of this cell adhesion, migration and proliferation is regulated by cell-surface carbohydrates. Specifically, P-4-galactosylated carbohydrate chains synthesized by P-4Gal-I play a critical role in the wound healing process (30).
Carbohydrates provide energy to wound cells, which helps in cell proliferation and phagocytic activity; however, more recently, carbohydrates have also been shown to play a variety of non-energy-related roles via their functions as communication or recognition markers when they are formed into glycoproteins or glycolipids. These roles become extremely important after a trauma, when the body must mobilize an immune response.
Carbohydrates have been found to play a significant role as components of glycoproteins in cell communication and have also been shown to have a wide variety of other critical roles (structural, lubricant, transport, immunologic, hormonal, and enzymatic). Over the past 20 years, glycoproteins have been shown to be altered by dietary intake of carbohydrates. Mannose and galactose have been shown to be directly used in the synthesis of glycoproteins by the liver and small intestine. Recent reviews indicate that when humans are fed only glucose, liver dysfunction is more common, and that the feeding of a variety of carbohydrates seems to alleviate some of these problems (31,32).
Recent work by Mori et al. showed that skin wound healing was impaired in mice that were P-1,4-galactosyltansferase deficient (28). Mice that were deficient in this key glycoprotein showed significantly delayed wound healing as well as reduced re-epithelialization, collagen synthesis, and angiogenesis. The authors speculate that the immune system is impacted, because both neutrophils and macrophages migrate into the wound site during wound healing, and this process is closely related to cell adhesion through interactions with selectins and their ligands. Chemokines were also shown to be reduced, and they have critical roles as chemoattractants for neutrophils and oncocytes/macrophages.
More detailed work regarding the role played by carbohydrates in wound healing has been done by studying rats that were either immunocompromised or aged. In this study, cutaneous cells were shown to depend on carbohydrates metabolism for wound healing. The key intermediate steps in energy metabolism that were altered included a decrease in the activity of the regulatory enzymes hexokinase and citrate synthase. These enzymes were altered, and this, in turn, impacted upon energy availability for cellular activity in the repair process (33). In this particular model, it appears that insulin and glucose uptake is less of an issue, and the problem lies more in a disturbed enzymatic role in the cutaneous cells.
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