Giovanni De Caridi

The Effect of PDRN, an Adenosine Receptor A2A Agonist, on the Healing of Chronic Diabetic Foot Ulcers: Results of a Clinical Trial

CONTEXT Foot ulcer is the principal cause of hospitalization for patients with diabetes. Polydeoxyribonucleotide (PDRN), an adenosine A2A receptor agonist, improves wound healing in diabetic mice. OBJECTIVE The aim of this study was to evaluate the effect of PDRN on chronic ulcer healing in patients with diabetes. DESIGN AND SETTING This randomized, double-blind, placebo-controlled trial, involved two medical centers in Italy. INTERVENTION Patients with diabetes showing hard-to-heal ulcers (Wagner grade 1 or 2) were randomly assigned to receive placebo (n = 106) or PDRN (n = 110). The treatments (PDRN and placebo) were performed for 8 weeks by intramuscular and perilesional route [corrected]. MAIN OUTCOME MEASURES The primary outcome was complete ulcer healing. Secondary outcomes were the days needed to complete wound closure and the reepithelialization of wound surface (as percentage of the original area). RESULTS After 8 weeks, 91 placebo and 101 PDRN subjects completed the study. Complete healing was achieved in 18.9% [95% confidence interval (CI) 11.4-26.3] of placebo and in 37.3% (95% CI 28.2-46.3) of PDRN-treated patients (P = .0027). After 8 weeks, PDRN increased the closure of foot ulcers in diabetic subjects (hazard ratio 2.20; 95% CI 1.29-3.75; P = .004). The median time to complete wound healing was 49 days for placebo (range 28-56 d) and 30 days for PDRN-treated subjects (range 14-56 d; P = .0027). The median epithelialized area of the ulcers (expressed as percentage) was 49.3% in the placebo and 82.2% in the PDRN group (P < .001). CONCLUSIONS PDRN facilitates the healing of Wagner 1 or 2 diabetic foot ulcers.

The effects of sulodexide on both clinical and molecular parameters in patients with mixed arterial and venous ulcers of lower limbs

Background Mixed venous and arterial ulcers account for approximately 15%–30% of all venous leg ulcerations. Several studies have shown that matrix metalloproteinases (MMPs) and neutrophil gelatinase-associated lipocalin (NGAL) play a central role in the pathophysiology of venous and arterial diseases. Some studies have shown the efficacy of glycosaminoglycans, such as sulodexide (SDX), in treating patients with leg ulcers. The aim of this study was to evaluate clinical effects of SDX and its correlation with MMPs and NGAL expression in patients with mixed arterial and venous leg ulcers. Methods Patients eligible for this study were of both sexes, older than 20 years, and with a clinical and instrumental diagnosis of mixed ulcer. Results Fifty-three patients of both sexes were enrolled and divided into two groups by means of randomization tables. Group A (treated group) comprised 18 females and ten males (median age: 68.7 years) treated with standard treatment (compression therapy and surgery) + SDX (600 lipoprotein lipase-releasing units/day intramuscularly) for 15 days followed by SDX 250 lipase-releasing units every 12 hours day orally for 6 months as adjunctive treatment. Group B (control group) comprised 17 females and eight males (median age: 64.2 years) treated with standard treatment only (compression therapy and surgery). The type of surgery was chosen according to anatomical level of vein incompetence: superficial venous open surgery and/or subfascial endoscopic perforating surgery. In all enrolled patients, blood samples were collected in order to evaluate the plasma levels of MMPs and NGAL through enzyme-linked immunosorbent assay. These results were compared to another control group (Group C) of healthy individuals. Moreover, biopsies of ulcers were taken to evaluate the tissue expression of MMPs and NGAL through Western blot analysis. Our results revealed that SDX treatment is able to reduce both plasma levels and tissue expression of MMPs improving the clinical conditions in patients with mixed ulcers. Conclusion Inhibition of MMPs could represent a possible therapeutic intervention to limit the progression of leg ulceration. In particular, our findings demonstrate the efficacy of SDX in patients with mixed arterial and venous chronic ulcers of the lower limbs.

Effects of a new nutraceutical substance on clinical and molecular parameters in patients with chronic venous ulceration.

Pathophysiological events involved in the onset of chronic venous ulceration (CVU) are inflammation, activation of polymorphonucleates (PMNs) and secretion of proteases such as matrix metalloproteinases (MMPs), which degrade extracellular matrix (ECM) that is a support for vascular and tissutal wall. MMPs, neutrophil gelatinase‐associated lipocalin (NGAL) and inflammatory cytokines are overexpressed in CVUs and they could play a central role in pathophysiological mechanisms of skin lesion and delayed wound healing. Bioflavonoids, such as diosmin and other compounds, appear to have several provessel function activities including anti‐inflammatory, antioxidant and phlebotonic effects and are widely used in the treatment of chronic venous disease (CVD)‐related problems.

Evidence for markers of hypoxia and apoptosis in explanted human carotid atherosclerotic plaques

OBJECTIVE Apoptosis and inflammation are important features of atherosclerotic plaques. We investigated whether a common signal molecule can trigger these two apparently separate pathways. Hypoxia inducible factor (HIF-1α) is known to participate in atherosclerosis and to stimulate apoptosis signal-regulating kinase 1 (ASK-1), one of the mitogen-activated protein kinases, which is activated by various extracellular stimuli and involved in a variety of cellular function. METHODS We tested carotid artery specimens from 50 subjects who underwent angioplasty and five age-matched controls for either Western blot or histologic analysis. The hypoxic status was investigated by means of HIF-1α expression in carotid specimens. RESULTS HIF-1α was significantly upregulated in carotid specimens with respect to controls (P < .05), ASK-1 was detected in plaques of any composition from lipidic to calcific, and this expression increased with the stage of the plaque and with the expression of inflammatory (p-ERK, RANK-L, OPG) and apoptotic molecules (caspase 9, p-p-38, and p-JNK). CONCLUSION Our data suggest that hypoxia is the key regulating factor that triggers inflammation as well as apoptosis in the human atherosclerotic plaque.

Perioperative Iloprost and Endothelial Progenitor Cells in Uremic Patients With Severe Limb Ischemia Undergoing Peripheral Revascularization

The incidence of severe limb ischemia (SLI) is high among haemodialysis (HD) patients. Limb rescue rate after surgical revascularization is relatively poor compared with patients with normal renal function. Prostanoids are an interesting category as adjuvants to revascularization. New vessel growth develops not exclusively by proliferation of endothelial cells in vascular extremities but also by cells mobilized from the bone marrow (HSC), transformed into endothelial progenitor cells (EPC) contributing to both re-endothelialization and neovascularization. Basal number of HSC and EPC is significantly reduced in HD patients and correlated with a subsequent defective neovascularization. The aim of this study was to evaluate the effects of perioperative treatment with iloprost in uremic patients with acute ischemia of lower limbs, undergoing surgical revascularization, on endothelial progenitor cells, hypothesizing a possible biological mechanism induced by the prostanoids. A search was also made for vascular remodeling processes through the analysis of the concentrations of soluble adhesion molecules (i-CAM, v-CAM, e-selectin), biochemical markers of endothelial activation. Thirty HD patients with SLI undergoing peripheral revascularization were enrolled (15 were treated with iloprost and 15 with a placebo). Iloprost was administered as an intra-arterial bolus of 3000 ng over 1 to 3 min immediately after revascularization and in the same affected artery. Serum samples were taken before revascularization (T0), at 6 (T6) and 24 h (T24) after infusion to measure sICAM-1, sE-selectin, and sVCAM-1, and for quantification of HSC and EPC. Progenitors were identified by specific surface markers CD34+, CD133+ and VEGFR2+. Count was conducted using PROCOUNT performed in a TRUCOUNT tube and with a FACSort flow cytometer. Before revascularization, all patients showed a decreased number of HSC and EPC. After 6 h, HSC augmented significantly compared with T0 in both groups. The iloprost group attained a significant increase compared with the placebo group. HSC levels reduced drastically at T24. EPC augmented significantly compared with basal level after 24 h. In the iloprost group, the increase was considerable compared with the placebo group. A close negative correlation, assessed by Pearson coefficient (r), was found between HSC and EPC at T24 in the iloprost group (R = 0.82 P < 0.01). Adhesion molecules had increased levels at T6 and T24 in both groups. Moreover, a close positive correlation, assessed by Pearson coefficient, was found between EPC and adhesion molecules in both groups but the iloprost group maintained a better statistical association. Revascularization stimulated HSC and EPC release from bone marrow but at a different time: HSC increased suddenly at 6 h and diminished to a minimal amount at T24, conversely, EPC increased significantly only at T24. Iloprost treatment was able to amplify this mechanism validating recent findings (North TE et al., [31]). Adhesion molecules as markers of endothelial activation and vascular development confirmed this tendency.

VAC therapy to promote wound healing after surgical revascularisation for critical lower limb ischaemia

Vacuum‐assisted closure (VAC) therapy is a new emerging non‐invasive system in wound care, which speeds up wound healing by causing vacuum, improving tissue perfusion and suctioning the exudates, and facilitating the removal of bacteria from the wound. The application of sub‐atmospheric pressure on the lesions seems to alter the cytoskeleton of the cells on the wound bed, triggering a cascade of intracellular signals that increase the rate of cell division and subsequent formation of granulation tissue. The aim of this study is to analyse the results of VAC therapy used as an adjuvant therapy for the treatment of foot wounds in patients affected by critical limb ischaemia (CLI) (Rutherford 6 class) after distal surgical revascularisation, to promote and accelerate the healing of ulcers. Twenty‐nine patients (20 males, 9 females; mean age 68·4) affected by CLI of Rutherford 6 class, after surgical revascularisation of the lower limb, underwent VAC therapy in order to speed up wound healing. Complete wound healing was achieved in 19 patients (65·51%), in an average period of 45·4 ± 25·6 days. VAC therapy is a valid aid, after surgical revascularisation, to achieve rapid healing of foot lesions in patients with CLI.

Interleukin-23 serum levels in patients affected by peripheral arterial disease.

OBJECTIVES To clarify whether interleukin (IL)-23 is involved in peripheral arterial disease (PAD). DESIGN AND METHODS We evaluated IL-23 serum levels, in 29 patients suffering from lower extremity PAD and in 30 healthy subjects. RESULTS IL-23 serum levels were higher during the three times (T0, T1 and T2) compared to the control group, although only statistically significant for T0 and T2: T0 (15.83 ± 22.08 vs. 8.08 ± 8.62 pg ml, p=0.026), T1 (16.10 ± 23.71 vs. 8.08 ± 8.62 pg/ml, p=0.101), T2 (15.06 ± 16.72 vs. 8.08 ± 8.62 pg/ml, p=0.005). CONCLUSION For the first time, our data gives us reason to believe there is an involvement of IL-23 in PAD.

Involvement of the aorta in brucellosis: the forgotten, life-threatening complication. A systematic review.

Human brucellosis is a disease of protean manifestations, and has been implicated in complications and focal disease in many human organ systems. However, little is collectively known about the background, the course, the clinical characteristics, the diagnostic issues raised, and the short- and long-term therapeutic approaches in patients with aortic involvement as a complication of brucellosis. With the aim to glean from the literature useful information to better understand and manage this complication, a computerized search without language restriction was conducted using PubMed and SCOPUS. An article was considered eligible for inclusion in the systematic review if it reported data on patients with involvement of the aorta due to a Brucella infection. The epidemiologic and clinical characteristics of 44 cases of brucellar aortic involvement found through the systematic review of the literature were analyzed together with those of two new cases that we treated in the recent past. This complication involved the ascending thoracic aorta in 18 cases (in 16 of them as a consequence of brucellar endocarditis), and the descending thoracic aorta or the abdominal aorta in the remaining 30 cases. In the latter it was associated with spondylodiscitis of the lumbar spine in 13 cases. History of or symptoms indicative of brucellosis were not universally present. Brucellar aortic involvement represents a possibly underdiagnosed and underreported complication with major morbidity and mortality potential. Experience with novel invasive therapeutic approaches remains limited. Early suspicion through detailed history and diagnosis, aided by advances in aortic imaging, would allow for better planning of therapeutic interventions.

From varices to venous ulceration: the story of chronic venous disease described by metalloproteinases.

Chronic venous disease (CVD) and its most frightening complication, chronic venous ulceration (CVU), represent an important socioeconomic burden in the western world. Metalloproteinases have been identified in the pathogenesis of several vascular diseases such as venous problems. The aim of this study was to evaluate a broad range of metalloproteinases, such as matrix metalloproteinases (MMPs), ADAMs (a disintegrin and metalloproteinases) and ADAMTSs (a disintegrin and metalloproteinases with thrombospondin motifs) and their inhibitors, tissue inhibitor of metalloproteinases (TIMPs) and a related protein, neutrophil gelatinase‐associated lipocalin (NGAL), in patients with CVD in order to correlate their serum levels with each stage of the disease. We performed a multicenter open‐label study that comprised the enrolment of 541 patients with CVD of clinical stages C1–C6, (178 males, 363 females; mean age 57·29, median age 53·72, age range 29–81); 29 subjects without CVD were included in this study (9 males and 20 females; mean age 54·44, median age 50, age range 28–84) as the control group. Enzyme‐linked immunosorbent assay (ELISA) was performed for measuring serum levels of proteases and related proteins. The study found that the serum elevation of MMP‐2, ADAMTS‐1 and ADAMTS‐7 appeared to be correlated with the initial stages of CVD, whereas the serum elevation of MMP‐1, MMP‐8, MMP‐9, NGAL, ADAM‐10, ADAM‐17 and ADAMTS‐4 was particularly involved in skin change complications. This study showed that each stage of CVD may be described by particular patterns of metalloproteinases, and this may have therapeutic implications in discovering new targets and new drugs for the treatment of CVD.

Adjuvant spinal cord stimulation improves wound healing of peripheral tissue loss due to steal syndrome of the hand: clinical challenge treating a difficult case

Hand ischaemia due to arterial steal syndrome is an infrequent, but potentially serious complication of arteriovenous fistula (AVF) for haemodialysis.