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Arginine is a basic amino acid that plays several pivotal roles in cellular physiology. Like any amino acid, it is involved with protein synthesis, but it is also intimately involved with cell signaling through the production of nitric oxide and cell proliferation through its metabolism to ornithine and the other polyamines. Because of these multiple functions, arginine is an essential substrate for wound healing processes. Numerous studies have shown that arginine supplementation can lead to normalization or improvement of healing. This article reviews the basic biochemistry and cell signaling within which arginine performs its functions. In particular, the requirement for this amino acid in tissue repair is highlighted.

The nitric oxide donor molsidomine can at least partially reverse impaired healing associated with diabetes.

OBJECTIVE -Tissue oxygen supply is crucial for wound healing. Especially in diabetic foot lesions, the chances for healing are mainly dependent on the presence or absence of ischemia. This study investigates the impact of the tissue O2 analysis system "O2C" for noninvasive quantification of tissue oxygenation in diabetic foot ulcer patients.RESEARCH DESIGN AND METHODS -O2C assessed relative blood flow (flow), flow velocity (velo), and hemoglobin concentration (rHb) and hemoglobin oxygenation (SO 2 ) at 2 and 6 mm depth (means Ϯ SE). 1) Measurements were performed on intact skin of the forefoot and forearm of 20 healthy volunteers on 2 consecutive days. 2) Parameters were assessed on intact skin of the forefoot of diabetic foot ulcer patients (n ϭ 14). 3) Measurements were performed directly at the wound site in diabetic patients (n ϭ 14).RESULTS -1) Flow, velo, rHb, and SO 2 at 2 and 6 mm depth were not significantly different when measured at 2 consecutive days. 2) There were no significant differences between diabetic subjects and healthy volunteers. Only flow in 6 mm depth was significantly higher in diabetic subjects (75 Ϯ 13 vs. 51 Ϯ 0.4 arbitrary units [AU], P Ͻ 0.05). When diabetic foot ulcer patients were split into healers and nonhealers, initial readings of SO 2 at 2 mm (32 Ϯ 6 vs. 44 Ϯ 3%, P Ͻ 0.05) and flow in 6 mm (28 Ϯ 1 vs. 51 Ϯ 0.6 AU, P Ͻ 0.05) were significantly reduced in nonhealers compared with control subjects, whereas in healers flow in 6 mm (70 Ϯ 0.6 vs. 51 Ϯ 0.6 AU, P Ͻ 0.05) was significantly higher than that in control subjects. 3) Initial SO 2 , rHb, flow, and velo were significantly lower in nonhealing compared with healing wounds.CONCLUSIONS -O2C is a new reliable and valid method for noninvasive measurement of tissue oxygenation and microvascular blood flow in patients with diabetic foot ulcers. Diabetes Care 27:2863-2867, 2004F oot ulcers are severe long-term complications in diabetic patients. In addition to local wound therapy, adequate tissue oxygenation is crucial for healing since oxygen is necessary for collagen formation, bactericidal activity of neutrophils, and endothelial cell function. Prognosis of diabetic foot lesions is mainly dependent on the presence or absence of tissue ischemia. However, quantitative assessment of peripheral perfusion and microcirculation is still challenging. Different methods like Doppler ultrasound or angiography are able to evaluate macrocirculation, but a reliable, easy technique to assess microcirculation, i.e., tissue perfusion, is not available. Previous studies have shown that healing might be predictable by measurement of transcutaneous oxygen tension (TcPO 2 ) (1-3). If TcPO 2 is Ͻ30 mmHg, complete healing cannot be expected (4). However, TcPO 2 is only a qualitative, not a quantitative, approach for evaluating peripheral perfusion and has a main limitation due to the need for heating the skin before measurement. This affects the resistance of skin vasculature and attenuates reflex mechanisms.Lightguide tissue spectrophotometry (O2C), ...