Comparative Genomic, MicroRNA, and Tissue Analyses Reveal Subtle Differences between Non-Diabetic and Diabetic Foot Skin

Diabetes Mellitus (DM) is a chronic, severe disease rapidly increasing in incidence and prevalence and is associated with numerous complications. Patients with DM are at high risk of developing diabetic foot ulcers (DFU) that often lead to lower limb amputations, long term disability, and a shortened lifespan. Despite this, the effects of DM on human foot skin biology are largely unknown. Thus, the focus of this study was to determine whether DM changes foot skin biology predisposing it for healing impairment and development of DFU. Foot skin samples were collected from 20 patients receiving corrective foot surgery and, using a combination of multiple molecular and cellular approaches, we performed comparative analyses of non-ulcerated non-neuropathic diabetic foot skin (DFS) and healthy non-diabetic foot skin (NFS). MicroRNA (miR) profiling of laser captured epidermis and primary dermal fibroblasts from both DFS and NFS samples identified 5 miRs de-regulated in the epidermis of DFS though none reached statistical significance. MiR-31-5p and miR-31-3p were most profoundly induced. Although none were significantly regulated in diabetic fibroblasts, miR-29c-3p showed a trend of up-regulation, which was confirmed by qPCR in a prospective set of 20 skin samples. Gene expression profiling of full thickness biopsies identified 36 de-regulated genes in DFS (>2 fold-change, unadjusted p-value ≤ 0.05). Of this group, three out of seven tested genes were confirmed by qPCR: SERPINB3 was up-regulated whereas OR2A4 and LGR5 were down-regulated in DFS. However no morphological differences in histology, collagen deposition, and number of blood vessels or lymphocytes were found. No difference in proliferative capacity was observed by quantification of Ki67 positive cells in epidermis. These findings suggest DM causes only subtle changes to foot skin. Since morphology, mRNA and miR levels were not affected in a major way, additional factors, such as neuropathy, vascular complications, or duration of DM, may further compromise tissue's healing ability leading to development of DFUs.

Transfection of human HGF plasmid DNA improves limb salvage in Buerger's disease patients with critical limb ischemia

AIM

Hepatocyte growth factor is a potent angiogenic agent. This study investigated the efficacy and safety of intramuscular injection of naked plasmid DNA encoding the human hepatocyte growth factor gene in Japanese patients with Buerger's disease and critical limb ischemia.

METHODS

An open-label clinical study was performed at eight hospitals in Japan from May 2004 to April 2008. Ten patients were enrolled. They had Buerger's disease with ischemic ulcers, were not candidates for revascularization, and were unresponsive to conventional drug therapy. Treatment consisted of 8 injections (total dose: 4 mg) of hepatocyte growth factor plasmid, which were administered into the calf muscles and/or distal thigh muscles of the ischemic limbs under ultrasound guidance. Administration was done twice at an interval of 4 weeks. If there was no improvement after 2 doses, a 3rd dose could be administered. The response to treatment was evaluated from the reduction of ischemic ulcer size.

RESULTS

The size of ischemic ulcers showed a decrease in 6/9 (66.7%) patients and the ulcers healed completely in 5/9 (55.6%) patients after gene therapy. Major amputation was not required. There were no deaths and no major safety concerns.

CONCLUSION

Hepatocyte growth factor gene therapy is safe and effective for critical limb ischemia in patients with Buerger's disease.

[Basal cell naevus syndrome as the cause of a chronic foot ulcer]

A 46-year-old man presented to the surgery outpatient clinic with an ulcer on top of his left foot. He had previously been diagnosed with basal cell naevus syndrome but had withdrawn from follow-up. His foot showed a deep ulcerating defect accompanied by profound necrosis extending to the metatarsophalangeal joints. There was a nodular skin defect over the first metatarsophalangeal joint, which was shown by histopathology to be a basal cell carcinoma, and the ulcer was bordered by a raised wall. Further physical examination revealed more than 200 dermal lesions which were identified by the dermatologist who was called in for consultation as basal cell carcinomas; multiple depressions due to abnormal local keratinisation were also seen on the palms of the hands and the soles of the feet. These findings led to a diagnosis of 'basal cell naevus syndrome'. The patient was treated by amputation of the lower leg followed by excision and curettage of the remaining basal cell carcinomas. At the time of the last follow-up, the patient was being checked periodically in the dermatology outpatient clinic. Basal cell naevus syndrome is a rare autosomal dominant hereditary disease. The prevalence is estimated to be between 1 in 57,000 and 1 in 164,000. Basal cell naevus syndrome is generally caused by a mutation in the 'patched homolog' (PTCH)-I gene, located on chromosome 9q22.3. Although the syndrome affects multiple organ systems, the most characteristic of this disorder is the appearance of multiple basal cell carcinomas.

Genetic Parameters for Claw Disorders in Dutch Dairy Cattle and Correlations with Conformation Traits

Impaired claw health is one of the major problems causing production loss and reduced animal welfare in dairy cattle. In response, the Dutch Animal Health Service (GD) Ltd. initiated this study, in which claws of lactating and near-term cows and heifers in 430 herds were trimmed by hoof trimmers and the health status of the rear claws recorded. Only herds with >75% of the animals having feet trimmed were considered, resulting in records on 21,611 animals. Eight claw disorders were scored: digital dermatitis (DD), interdigital dermatitis/heel horn erosions (IDHE), sole hemorrhage (SH), chronic laminitis (CL), sole ulcer (SU), white line disease (WLD), interdigital hyperplasia (HYP), and interdigital phlegmona (IP). The prevalence varied from 0.6% (IP) to 39.9% (SH). More than 70% of the animals had at least one claw disorder. Conformation traits and locomotion were recorded once during the animal's first lactation by trained classifiers of the Royal Dutch Cattle Syndicate and completely independent of the moment of claw trimming. Heritabilities were estimated using a sire model, and ranged from <0.01 (IP) to 0.10 (DD and HYP). Genetic correlations of incidences of claw disorders with locomotion were variable, ranging from 0.13 (SH) to -0.91 (CL). Genetic correlations with the rear leg conformation traits were lower, ranging from 0.04 (ID with rear leg side view) to -0.69 (IP with rear leg rear view).

Chronic leg ulcers in Werner's syndrome

We report two siblings suffered from Werner's syndrome, which is a rare premature aging disorder caused by genetic mutations. They developed premature aging during adolescence with loss and graying of hair, short stature, baldness, atrophic skin, thin extremities, flat feet, 'bird' face and cataracts. Multiple chronic ulcers were noted over the feet in both patients. Healing was prolonged because of atrophic subcutaneous tissue, poor perfusion, impaired fibroblast activity and the loss of normal foot architecture. Treatment of the ulcers was challenging, as flap options were limited over the lower third of the leg and skin grafting was not easy as there was a lack of healthy granulations. However, we have successfully closed the ulcers with Integra artificial skin and ultra-thin split thickness skin grafting with the scalp as donor site. The main purpose of this paper is to alert physicians to this syndrome when treatments are being planned for patients with chronic leg ulcers.

Familial cutaneous vasculopathy and demodicosis in a German shepherd dog

A two-month-old female German shepherd dog was presented with a history of ulcerated central pads of all four feet. On physical examination, the footpads were swollen, soft and ulcerated. On the nasal planum there was a partially depigmented nodule. Multiple biopsies were taken from the cutaneous lesions and histological examination revealed focal collagen degeneration and vasculitis. A diagnosis of familial cutaneous vasculopathy was made. Seven months later the nasal nodule had disappeared and the footpads were still swollen but non-ulcerated. At this time, the dog manifested a generalised pustular demodicosis.

Mutilating neuropathic ulcerations in a chromosome 3q13-q22 linked Charcot-Marie-Tooth disease type 2B family

BACKGROUND

Charcot-Marie-Tooth disease type 2 (CMT2) or hereditary motor and sensory neuropathy type II (HMSN II) is an inherited axonal neuropathy of the peripheral nervous system. Three autosomal dominant CMT2 loci have been located on chromosomes 1p35-p36 (CMT2A), 3q13-q22 (CMT2B), and 7p14 (CMT2D) indicating that CMT2 is a genetically heterogeneous disorder.

METHODS

A CMT2 family was examined for linkage to the CMT2A, CMT2B, and CMT2D loci using short tandem repeat polymorphisms.

RESULTS

Suggestive evidence for linkage to 3q13-q22 was found. Recombinations occurred with markers D3S1769 and D3S1267 indicating that the CMT2B locus is located distal to D3S1267 and resides in an interval of 25 cM. Some patients in this family have pronounced sensory disturbances leading to poorly healing ulcerations.

CONCLUSIONS

These unusual sensory signs for CMT were also noted in the only other CMT2B family reported so far, suggesting a distinct clinical phenotype for CMT2B. Exclusion of the locus for hereditary sensory neuropathy type I (HSN I) on chromosome 9q22 indicates that HSN I with mild motor symptoms and CMT2 with prominent sensory abnormalities are not allelic.

[The differential diagnosis of syringomyelia from pseudosyringomyelitic ulcero-mutilating acropathy]

The authors describe some differential diagnostic criteria of atypical syringomyelia and pseudosyringomyelitic acropathy. It was found that trophic disorders in the skin, metatarsal bones were in atypical syringomyelia usually associated with sensibility disorders of the dissociated type in the zone of corresponding segments. In pseudosyringomyelitic acropathy trophic and skin changes precede sensibility disorders and do not always correspond to innervation zones of the lower extremities. Dysraphic state is of importance for the diagnosis of syringomyelia.