Aging is a biologic process characterized by time-dependent functional declines that are influenced by oxidative stress-induced inflammatory reactions. In particular, ultraviolet (UV) irradiation plays a key role in cellular senescence in photo-aged skin. However, the cellular senescence of epidermal keratinocytes and dermal fibroblasts by UV irradiation may differ depending on the exposure time and dosage of UV irradiation. Therefore, the purpose of the study was to evaluate and compare the effects of UV irradiation on cellular senescence in human epidermal keratinocytes (HaCaT) and human dermal fibroblasts (HDFs). After cell viability test, 200 mJ/cm2 UV irradiation was used in this study. To evaluate the reactive oxygen species and reactive nitrogen species production, the levels of glutathione (GSH) and nitrite (NO2) were measured. We also performed reverse transcription-polymerase chain reaction, Western blot analysis, and senescence-associated beta-galactosidase assay. An overall decrease in GSH and an increase in NO2 were observed in the HaCaT and HDF cells. However, the time-line and dose-dependent effects varied. Higher expressions of tumor necrosis factor-α, inducible nitric oxide synthase, and interleukin-1β than that of the control group were observed in both cells. The HDF cells showed high levels of matrix metallopeptidase 9 and neutral endopeptidase protein but low levels of SIRT1 and procollagen I. The expression of nuclear factor kappa-light-chain-enhancer of activated B cell (NF-κB) was increased in the HaCaT cells, but not in the HDF cells. The NF-κB peaked at 1 hour after UV irradiation in the HaCaT cells. The “turning-on” signal was faster in the irradiated HaCaT cells.

BACKGROUND Patients with diabetic foot commonly experience vascular insufficiency and compromised tissue perfusion. Extracorporeal shockwave therapy (ESWT) reportedly promotes wound healing and angiogenesis, but clinical studies on the effect of ESWT on angiogenesis are scarce and the exact mechanism remains unclear. OBJECTIVE To investigate the effect of ESWT on cutaneous microcirculation in diabetic feet. METHODS Ten patients with diabetic feet received ESWT twice weekly for a total of six sessions. Transcutaneous partial oxygen pressure (Tcpo 2) and cutaneous blood flow were measured before and after ESWT. MAIN RESULTS The treated feet showed statistically significant improvements in the mean Tcpo 2 (P < .01) and cutaneous blood flow level (P < .05) compared with control feet. In treated feet, Tcpo 2 increased by 19.6%, from 41.4 ± 9.9 to 49.5 ± 8.7 mm Hg (P < .05). In control feet, Tcpo 2 decreased by 11.6%, from 39.5 ± 14.0 to 34.9 ± 14.5 mm Hg (P = .059). The average cutaneous blood flow level of treated feet before ESWT was 36.9 ± 25.6, which increased to 48.3 ± 32.4 AU after ESWT (30.9% increase; P = .646). In control feet, the cutaneous blood flow level decreased from 80.5 ± 36.7 to 60.4 ± 38.8 AU, a decrease of 25.0% (P = .241). CONCLUSIONS These results demonstrate that ESWT may have beneficial effects on microcirculation in diabetic feet.

Percutaneous transluminal angioplasty (PTA) is now more frequently used to improve tissue perfusion in ischemic diabetic feet. However, there are concerns about its feasibility and effectiveness in severely ischaemic feet. This study aimed to compare the perfusion values after PTA according to the ischaemic degree of diabetic feet. This study included 133 ischaemic diabetic feet. The foot transcutaneous oxygen pressure (TcPO2) and toe pressure were measured before the procedure and every second postoperative week for 6 weeks. The patients were divided into three groups according to ischaemic severity on the basis of TcPO2 and toe pressures. In the “severely ischaemic” group, the TcPO2 increased from 7.5 ± 4.9 to 40.3 ± 11.3 mm Hg (5.4‐fold) 6 weeks after the PTA (P < 0.001). The toe pressure increased from 8.5 ± 8.8 to 42.2 ± 19.3 mm Hg (5.0‐fold, P < 0.001). In the “mild” group, the TcPO2 increased from 35.4 ± 2.5 to 41.8 ± 12.4 mm Hg (1.2‐fold, P = 0.003), and the toe pressure increased from 45.7 ± 12.3 to 54.3 ± 31.3 mm Hg (1.2‐fold, P > 0.05). Results of the “intermediate” group were in between. The most severely ischaemic group had the most dramatic increase of tissue perfusion after PTA. As such, PTA can be an effective method for increasing tissue perfusion even in the severely ischaemic diabetic feet.

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