Diabetic Foot

MicroRNA miR-145-5p Inhibits Cutaneous Wound Healing by Targeting PDGFD in Diabetic Foot Ulcer

Diabetic foot ulcer (DFU) is one major, common and serious chronic complication of diabetes mellitus, which is characterized by high incidence, high risk, high burden, and high treatment difficulty and is a leading cause of disability and death in patients with diabetes. Long-term hyperglycemia can result in cellular dysfunction of fibroblasts, which play pivotal roles in wound healing. MicroRNAs (miRNAs) were reported to mediate the pathological processes of multiple diseases, including diabetic wound healing. This research aimed to investigate the functional role of miR-145-5p in high-glucose (HG)-exposed fibroblasts and in DFU mouse models. Human foreskin fibroblast cells (HFF-1) were stimulated by HG to induce cell injury. MiR-145-5p level in HG-stimulated HFF-1 cells was detected via RT-qPCR. The binding between miR-145-5p and PDGFD was validated by Luciferase reporter assay. The effects of the miR-145-5p/PDGFD axis on the viability, migration, and apoptosis of HG-exposed HFF-1 cells were determined by CCK-8, wound healing, and flow cytometry assays. DFU mouse models were subcutaneously injected at the wound edges with miR-145-5p inhibitor/mimics. Images of the wounds were captured on day 0 and 8 post-injection, and wound samples were collected after mice were sacrificed for histological analysis by H&E staining. HG decreased cell viability and increased miR-145-5p expression in HFF-1 cells in a dose- and time-dependent manner. MiR-145-5p downregulation promoted cell viability and migration and inhibited cell apoptosis of HG-stimulated HFF-1 cells, while miR-145-5p overexpression exerted an opposite effect on cell viability, migration, and apoptosis. PDGFD was a direct target gene of miR-145-5p, whose silencing reversed the influence of miR-145-5p downregulation on HG-induced cellular dysfunction of HFF-1 cells. Additionally, downregulating miR-145-5p facilitated while overexpressing miR-145-5p inhibited wound healing in DFU mouse models. MiR-145-5p level was negatively associated with PDGFD level in wound tissue samples of DFU mouse models. MiR-145-5p inhibition improves wound healing in DFU through upregulating PDGFD expression.

Knowledge, Attitude and Practice Regarding Risk of Diabetic Foot Among Diabetic Patients in Aseer Region, Saudi Arabia

Background

Diabetic foot care is vital as it is preventable complication but dangerous even a small trauma can end with serious consequences. Diabetes may cause nerve damage that affects feet sensation. Diabetes may also reduce blood flow to the feet, making it harder to heal an injury or resist infection. Because of these problems, patients may lose notice of early foot abnormalities. Diabetic patients’ awareness regarding how to care for their feet plays a significant role in preventing these complications.

Methods

A correlation cross-sectional study was conducted targeting all diabetic patients aging 20 years or more. Online questionnaire was used for data collection. Questionnaire was uploaded online using social media platforms by the researchers and their relatives and friends. The questionnaire included patient personal data, patients’ knowledge regarding diabetic foot, attitude and practice regarding the risk of diabetic foot among diabetic patients.

Results

A total of 1,000 diabetic patients fulfilling the inclusion criteria completed the study questionnaire. Exact of 77.5% of the patients know that Diabetics can get gangrene in the foot, 74.9% know diabetics can develop ulcers in the foot, 66.7% reported that Diabetes can reduce blood flow to the feet of diabetic patients, 66.6% agreed that diabetic patients can suffer from a lack of sensation in the feet. Exact of 84.5% of the study participants agreed that Diabetics should check for any wounds on their feet daily, 78.7% agreed that Diabetics should visit a doctor when there is any infection or wound in the feet, 76.6% think that diabetic patients should wear specialized shoes to avoid diabetic foot according to the doctor's instructions. A total of 822 (82.2%) of the study patients wash their feet daily, and 295 (29.5%) usually wear cotton socks regularly and 39.6% sometimes wear the stock. Only 192 (19.2%) regularly walk barefoot and 41.7% sometimes do.

Conclusion

In conclusion, the current study results showed that nearly two out of each three diabetic patients were knowledgeable for diabetic foot and its care. High knowledge was associated with young age, high education and having family member with diabetes mellitus (DM). Also, patients had a good attitude towards diabetic foot care and the effect of diabetes on foot health with to some level accepted practice except for some issues.

Efficacy of the therapy of 5-aminolevulinic acid photodynamic therapy combined with human umbilical cord mesenchymal stem cells on methicillin-resistant Staphylococcus aureus-infected wound in a diabetic mouse model

BACKGROUND

A distressing issue of diabetic ulcer (DU) is its poor healing feature with limited clinical solutions. We have previously shown that 5-aminolevulinic acid photodynamic therapy (ALA-PDT) is a promising alternative to the currently limited measures for DU. Mesenchymal stem cells (MSCs) transplantation has been believed to impose certain therapeutic effect on restoration of injury. Thus, this study aims to explore whether the combination of MSCs and ALA-PDT will exert a more advanced curative effect on DU.

METHODS

Diabetic mice were induced by intraperitoneal injection of streptozotocin (STZ, 60 mg/kg/d) for consecutive 5 days. A full-thickness skin injury (diameter 6 mm) was created in the center of the back of each mouse, and then 10 μl of methicillin-resistant Staphylococcus aureus (MRSA) suspension was added to establish an infected DU model. All DU models were randomly divided into four groups: Untreated group, MSCs group, ALA-PDT group, and ALA-PDT combined with human umbilical cord mesenchymal stem cells (hUC-MSCs) (ALA-PDT + MSCs) group. The wound sizes were recorded by a digital camera, and the healing rates were calculated using Image J software. Bacterial loads on wounds were measured using CFU (Colony forming units) analysis. The epithelialization, inflammatory cells infiltration and granulation tissue formation were monitored by Haematoxylin and eosin (H&E) staining, and the corresponding semi-quantitative score was matched. Growth and pro-inflammatory cytokines were detected by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Either ALA-PDT or injection of hUC-MSCs resulted in a rapid wound closure compared with the untreated, while their combination brought about the most prominent healing. On day 12, healing rates of the untreated, MSCs, ALA-PDT and ALA-PDT + MSCs were 40.56% ± 7.06%, 74.23 ± 4.83%, 84.03 ± 3.53%, 99.67 ± 0.49%, respectively. The bacterial burden reductions were approximately 1.58 logs (97.36%, P < 0.05), 2.34 logs (99.54%, P < 0.01), 4.50 logs (nearly 100%, P < 0.001) for MSCs, ALA-PDT and ALA-PDT + MSCs, respectively. Histology revealed reduced inflammatory cells and improved collagen precipitation and angiogenesis after hUC-MSCs and ALA-PDT treatment compared to the untreated. The combined therapy leaded to a more intact epithelium, similar to the healthy. Finally, ELISA revealed that the property of ALA-PDT to stimulate transforming growth factor-β1 (TGF-β1) and vascular endothelial growth factor (VEGF) and inhibit IL (interleukin) -1β and IL-6 outweighed that of hUC-MSCs, and this function of the combination overwhelmed that of any single therapy.

CONCLUSIONS

Our findings indicated that the strategy of combining ALA-PDT with hUC-MSCs possessed a significantly enhanced therapeutic effect over either single therapy, providing a promising innovative therapeutic candidate for refractory wounds.

An Overview of Ozone Therapy for Treating Foot Ulcers in Patients With Diabetes

Diabetic foot ulcer (DFU) is one of the most common and severe complications of diabetes mellitus, which is becoming increasingly prevalent throughout the world, with high mortality and morbidity. Because of the complex pathophysiological processes involved, DFU is difficult to treat effectively with traditional therapies. Ozone therapy, an emerging method, has been reported as potentially beneficial for closure of DFUs and may gradually move to the forefront of clinical practice. Possible mechanisms of action include antioxidant capacity, pathogen inactivation, vascular and endogenous growth factor modulation, and immune system activation. However, some researchers are skeptical about its safety, and clinical trials are lacking. This article reviews the current research and application of ozone therapy for DFUs.

The role of microRNAs in the healing of diabetic ulcers

MicroRNAs (miRNAs) are small protected molecules with a length of 18 to 25 nucleotides. Many studies have recently been conducted on miRNAs, illustrating their role in regulating many biological, physiological, and pathological activities, such as maintaining cellular signalling and regulating cellular pathways. The main role of miRNAs is to regulate the expression of genes after translation, which can lead to the destruction or suppression of translation by binding to mRNAs. As any change in the regulation of miRNAs is associated with several physiological abnormalities, such as type 2 diabetes and its complications, these molecules can be used for therapeutic purposes or as biomarkers for the diagnosis of diseases such as diabetes and its complications. In this review article, we will discuss important findings about the miRNAs and the role of these molecules in different phases of the wound-healing process of chronic wounds, especially diabetic ulcer.

α-ketoglutarate is associated with delayed wound healing in diabetes

AIM

A high level of matrix metalloproteinase 9 (MMP-9) is a predictor of poor wound healing in diabetic foot ulcers. In skin keratinocytes, site-specific DNA demethylation plays an important role in MMP-9 expression. Ten-eleven translocation enzyme 2 (TET2) protein, one member of TET family, could rely on α-ketoglutarate (α-KG) as cosubstrate to exhibit catalytic activity of DNA demethylation. Here, we aimed to explore the changes of α-KG and its relationship with MMP-9 and TET2 during diabetic wound healing.

METHODS

Seventy-one cases of patients with diabetic foot ulcers and 53 cases of nondiabetic ulcers were enrolled. Serum, urine and wound fluids were collected for measurement of α-KG levels and MMP-9 expression. Skin tissues were collected for the measurement of TET2 and MMP-9 expression. Clinical parameters were collected, and transcutaneous oxygen pressure (TcPO2) levels of feet were detected.

RESULTS

The levels of α-KG, TET2 and MMP-9 were significantly increased in diabetic wound compared with nondiabetic wound (P = 0·010, 0·016 and 0·025). There was a significant correlation between a low TcPO2 and a high α-KG level of wound fluids (r = -0·395, P = 0·002). Further analysis showed that α-KG concentration had a positive correlation with both haemoglobin A1c (HbA1C) and 2 h postprandial blood glucose (PBG) (r = 0·393, P = 0·005; r = 0·320, P = 0·025, respectively).

CONCLUSIONS

The levels of α-KG, TET2 and MMP-9 were significantly increased in diabetic wound compared with nondiabetic wound. Elevated α-KG was related to local hypoxia ischaemia status and systematic poor glycaemic control.

Topical Therapy As Adjuvant Treatment to Save a Limb With Critical Ischemia From Extensive and Deep Diabetic Foot Infection When Revascularization Is Not Feasible

BACKGROUND

Patients with diabetes mellitus are susceptible to foot ulcerations associated with the complex triad of peripheral sensory neuropathy, vasculopathy, and trauma. Local infection of a diabetic foot ulcer (DFU) acts a significant deterrent to healing because the response to aggressive debridement antimicrobial therapy is limited when peripheral circulation is poor.

CASE REPORT

We share an experience of using silver-impregnated hydrofiber wound dressing as an alternative to amputation in an 85-year-old female patient with an infected, ischemic DFU. This patient had a long-standing history of diabetes mellitus and hypertension for more than 30 years; both conditions were managed with oral medications. Penetrative injury caused by toothpicks resulted in 2 ulcers over the right lateral and medial plantar areas of her right foot. The DFUs were present within a period of 6 months. Due to the deep wound and progressively worsening infection, she was admitted for systemic antibiotics, debridement, and plantar fasciotomy. Percutaneous transluminal angioplasty was indicated, but the patient refused due to concerns related to potential nephrotoxicity associated with contrast use. Amputation was proposed as the final resort if the critical ischemia showed no improvement. Before undertaking amputation, silver-impregnated hydrofiber dressings were applied to the DFUs, along with antiplatelet medications. Following 4 months of treatment, the right medial plantar ulcer healed completely and the DFU over the lateral plantar ulcer was 75% smaller in surface area. Both DFUs remained healed when evaluated at 8 months.

CONCLUSION

We found that a silver-impregnated hydrofiber dressing, combined with antiplatelet medications, allowed the patient to avoid amputation despite 2 deep and extensively infected DFUs with critical limb ischemia when revascularization was not feasible.

Quality Randomized Clinical Trials of Topical Diabetic Foot Ulcer Healing Agents

Significance: Diabetic foot ulcers (DFU) significantly add to global economic, social, and clinical burdens. Healing a DFU fast and well limits complications that can lead to lower extremity amputation, morbidity, and mortality. Recent Advances: Many promising topical DFU healing agents have been studied in randomized clinical trials (RCT), but only one, becaplermin, has been cleared for this use by the United States Food and Drug Administration (FDA). Critical Issues: This critical review of DFU topical healing RCTs summarizes issues identified in their design and conduct, highlighting ways to improve study quality so researchers can increase the likelihood of RCT success in propelling effective topical DFU healing agents toward clinical use. Key issues include (1) inadequate sample size, (2) risk of bias, (3) irrelevant or unreported inclusion criteria, (4) substandard outcome measures, (5) unmatched group characteristics that predict nonhealing at baseline, (6) unequal or uncontrolled concurrent interventions or standard of care, (7) heterogeneous subject or DFU samples (8) unblinded allocation, treatment, or outcome measures, or (9) inadequate follow-up for clinical relevance. These can add bias or unexplained variability to RCT outcomes, limiting clinical or statistical significance and accuracy of results. Future Directions: This critical review summarizes ways to overcome these deficiencies to optimize DFU clinical trial design and conduct. It provides a blueprint for future excellence in RCTs testing safety and efficacy of topical DFU healing agents and smoothing the path to their clinical use.

Ozone therapy for treating foot ulcers in people with diabetes

BACKGROUND

It has been reported that ozone therapy might be helpful in treating foot ulcers in people with diabetes mellitus (DM).

OBJECTIVES

To assess the effects of ozone therapy on the healing of foot ulcers in people with DM.

SEARCH METHODS

In March 2015 we searched: The Cochrane Wounds Group Specialised Register, The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), Ovid MEDLINE, Ovid MEDLINE (In-Process & Other Non-Indexed Citations), Ovid EMBASE, EBSCO CINAHL, Science Citation Index, Chinese Biomedical Literature Database and The Chinese Clinical Registry. There were no restrictions based on language, date or study setting.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared ozone therapy with sham ozone therapy or any other interventions for foot ulcers in people with DM, irrespective of publication date or language.

DATA COLLECTION AND ANALYSIS

Two reviewers independently screened all retrieved citations, selected relevant citations and extracted data. Disagreements were resolved by discussion with a third reviewer. The methodological quality of included studies and the evidence level of outcomes were assessed using the Cochrane risk of bias tool and the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach respectively. Data were expressed using risk ratio (RR) for dichotomous outcomes and mean difference (MD) for continuous outcomes with their 95% confidence interval (95% CI). Review Manager (RevMan) software was used to analyse the data.

MAIN RESULTS

Three studies (212 participants) were included in this review. The overall risk of bias was high for two trials and unclear for one.One trial (101 participants) compared ozone treatment with antibiotics for foot ulcers in people with DM. The study had a follow-up period of 20 days. This study showed that ozone treatment was associated with a greater reduction in ulcer area from baseline to the end of the study than treatment with antibiotics (MD -20.54 cm(2), 95% CI -20.61 to -20.47), and a shorter duration of hospitalisation (MD -8.00 days, 95% CI -14.17 to -1.83), but did not appear to affect the number of ulcers healed over 20 days (RR 1.10, 95% CI 0.87 to 1.40). No side effects were observed in either group.The other two trials (111 participants) compared ozone treatment plus usual care with usual care for foot ulcers in people with DM. The meta-analysis results did not show evidence of a difference between groups for the outcomes of reduction of ulcer area (MD -2.11 cm(2), 95% CI -5.29 to 1.07), the number of ulcers healed (RR 1.69, 95% CI 0.90 to 3.17), adverse events (RR 2.27, 95% CI 0.48 to 10.79), or amputation rate (RR 2.73, 95%CI 0.12, 64.42).

AUTHORS' CONCLUSIONS

The available evidence was three small RCTs with unclear methodology, so we are unable to draw any firm conclusions regarding the effectiveness of ozone therapy for foot ulcers in people with DM.

The Role of MicroRNAs in Diabetic Complications-Special Emphasis on Wound Healing

Overweight and obesity are major problems in today’s society, driving the prevalence of diabetes and its related complications. It is important to understand the molecular mechanisms underlying the chronic complications in diabetes in order to develop better therapeutic approaches for these conditions. Some of the most important complications include macrovascular abnormalities, e.g., heart disease and atherosclerosis, and microvascular abnormalities, e.g., retinopathy, nephropathy and neuropathy, in particular diabetic foot ulceration. The highly conserved endogenous small non-coding RNA molecules, the micro RNAs (miRNAs) have in recent years been found to be involved in a number of biological processes, including the pathogenesis of disease. Their main function is to regulate post-transcriptional gene expression by binding to their target messenger RNAs (mRNAs), leading to mRNA degradation, suppression of translation or even gene activation. These molecules are promising therapeutic targets and demonstrate great potential as diagnostic biomarkers for disease. This review aims to describe the most recent findings regarding the important roles of miRNAs in diabetes and its complications, with special attention given to the different phases of diabetic wound healing.