Diabetic Limb Research Articles

Investigating Nonadherence in an Integrated Diabetic Limb Salvage Programme: Reasons, Associated Factors, and Impacts on Care Outcomes.

Adherence to treatment plans is crucial for patients with diabetic foot ulcers (DFUs) to achieve positive outcomes. With limited understanding of nonadherence and its impacts on care outcomes, this study aimed to explore the reasons and factors associated with nonadherence in an integrated diabetic limb salvage (DLS) programme and evaluate its effects on care outcomes. This study included 2798 DFU patients who were enrolled in an integrated DLS programme across multiple institutions in central and northern Singapore from 2020 to 2021. Reasons for nonadherence were obtained via telephone interviews. Factors associated with nonadherence were identified using multiple logistic regression. Differences in one-year outcomes, including minor and major lower extremity amputation (LEA), mortality, LEA-free survival, and healthcare utilisation between adherent and nonadherent patients, were examined based on a significance level of P < .05. Nonadherence was observed in 40.2% of patients, with higher rates among younger patients, Malays and Indians, and those with higher HbA1c levels. Patient-related factors were the most commonly reported reasons for missed appointments (50.4%). Compared to adherent patients, nonadherent patients exhibited a relatively higher minor LEA rate (13.0% vs 10.2%, OR = 1.18, 95% CI: 0.93, 1.51), lower mortality rate (8.6% vs18.1%, OR = 0.50, 95% CI: 0.39, 0.65), higher overall LEA-free survival (76.4% vs 71.1%, OR = 1.27, 95% CI: 1.06, 1.53), and more hospitalisations (IRR = 1.22, 95% CI: 1.11, 1.33) and emergency visits (IRR = 1.27, 95% CI: 1.16, 1.39). While nonadherent patients showed relatively higher minor LEA rates and more healthcare utilisation, they also exhibited lower mortality and higher LEA-free survival. This suggests that nonadherence in this population may be associated with complex patient characteristics and behaviours that warrant further investigation to tailor interventions effectively.

Netrin1-Enriched Exosomes From Genetically Modified ADSCs as a Novel Treatment for Diabetic Limb Ischemia.

Diabetic limb ischemia (DLI) is a frequent complication of diabetes and the leading cause of non-traumatic amputation. Traditional treatments like stent placement and bypass surgery may not suit all patients. Exosome transplantation has emerged as a promising therapy. Netrin1, a protective cardiovascular factor, has an unclear role in DLI. This study investigates the role of Netrin1 in DLI patients and evaluates the therapeutic potential of exosomes derived from Netrin1-overexpressing adipose-derived stem cells (N-ADSCs). The expression of Netrin1 is significantly decreased in both endothelial cells and serum of DLI patients, highlighting its potential as a biomarker or therapeutic target. In vitro, Netrin1-enriched exosomes (N-Exos) promoted human umbilical vein endothelial cell (HUVEC)proliferation, migration, tube formation, and increased resistance to apoptosis under high glucose conditions. These protective effects are mediated through PI3K/AKT/eNOS and MEK/ERK pathways, and N-Exos further facilitated macrophage polarization from M1 to M2. In vivo, N-Exos demonstrates superior therapeutic effects over ADSC exosomes (Exos), including enhanced angiogenesis, improved collateral artery remodeling, reduced inflammation, and muscle protection. Collectively, these findings identify Netrin1 as a critical factor in DLI and underscore its significance in disease progression and therapeutic strategies. N-Exos offers a promising non-cellular therapeutic approach for the treatment of DLI.

Abstracts from "Diabetic Limb Salvage: A Team Approach, 10-13th April 2024, Washington DC, USA-A joint meeting between Diabetic Limb Salvage and Wound Healing Foundation.

Abstracts from "Diabetic Limb Salvage: A Team Approach, 10-13th April 2024, Washington DC, USA-A joint meeting between Diabetic Limb Salvage and Wound Healing Foundation.

Histone Mono-methylation by SETD7 Orchestrates Angiogenic Response in Diabetic Limb Ischemia

Abstract Background Peripheral artery disease (PAD) is highly prevalent in patients with diabetes (DM) and associates with a high rate of limb amputation and poor prognosis. Surgical and catheter-based revascularization have failed to improve outcome in DM patients with PAD. Hence, a need exists to develop new treatment strategies able to promote blood vessel growth in this setting. Mono-methylation of histone 3 at lysine 4 (H3K4me1) - a specific epigenetic signature induced by the histone methyltransferase SETD7 - favours an open chromatin thus enabling gene transcription. Purpose: To investigate whether SETD7-dependent epigenetic changes modulate angiogenic response in diabetes. Methodology: Primary human aortic endothelial cells (HAECs) were exposed to normal glucose (NG, 5 mM) or high glucose (HG, 25 mM) concentrations for 48 hours. Unbiased gene expression profiling was performed by RNA sequencing (RNA-seq) followed by Ingenuity Pathway Analysis (IPA). In vitro assays, namely cell migration and tube formation were employed to study angiogenic properties in HAECs. SETD7 and H3K4me1 levels were investigated by Western blot and Chromatin immunoprecipitation (ChIP). Pharmacological blockade of SETD7 was achieved by using the highly selective inhibitor (R)-PFI-2. Mice with streptozotocin-induced diabetes were orally treated with (R)-PFI-2 or vehicle and underwent hindlimb ischemia by femoral artery ligation for 14 days. Blood flow recovery was analysed at 30 minutes, 7 and 14 days by laser Doppler imaging. Our experimental findings were also translated in gastrocnemius muscle samples from patients with and without diabetes. Results RNA-seq in HG-treated HAECs revealed a profound upregulation of the methyltransferase SETD7, an enzyme involved in mono-methylation of lysine 4 at histone 3 (H3K4me1). SETD7 upregulation in HG-treated HAECs was associated with increased H3K4me1 levels as well as with impaired endothelial cell migration and tube formation. Both SETD7 gene silencing and pharmacological inhibition by (R)PFI-2 rescued hyperglycemia-induced impairment of HAECs migration and tube formation, while SETD7 overexpression blunted the angiogenic response. RNA-seq and ChIP assays showed that SETD7-dependent H3K4me1 regulates the transcription of the angiogenesis inhibitor semaphorin-3G (SEMA-3G, (Figure 1). Moreover, SEMA-3G overexpression blunted migration and tube formation in SETD7-depleted HAECs. In diabetic mice with hindlimb ischemia, treatment with (R)-PFI-2 improved limb vascularization and perfusion as compared to vehicle (Figure 2). Finally, SETD7/SEMA3G axis was upregulated in muscle specimens from T2D patients as compared to controls (Figure 2) Conclusion: Targeting SETD7 represents a novel epigenetic-based therapy to boost neovascularization in diabetic patients with PAD.

Ambulatory Status before Diabetic Foot Ulcer Development as a Predictor of Amputation and 1-Year Outcomes: A Retrospective Analysis.

Up to 25% of people with diabetes develop a diabetic foot ulcer (DFU) during their lifetime, which precedes approximately 85% of nontraumatic lower limb amputations. Diabetic limb salvage has been at the forefront of recent research, as major amputation is associated with 5-year mortality rates of 52%-80%. We sought to determine if ambulatory status before DFU diagnosis is predictive of amputations and outcomes within 1 year, as no studies have directly examined this relationship. A retrospective review of patients diagnosed with DFUs from January 2011 to December 2021 was performed. Patients aged 18 years or more with type II diabetes were included. Ambulatory status was defined as the primary form of mobility reported by the patient before development of DFU, and was categorized as independent ambulation, ambulatory with assisting device (AWAD), or nonambulatory (NA). Statistical analyses included χ2, multinomial, and multivariable logistic regressions. After review, 506 patients were included. NA (OR = 5.10; P = 0.002) and AWAD status (OR = 2.77; P = 0.01) before DFU development were predictive of major (below or above-knee) amputation during hospitalization, emergency department visits within 30-days (NA: OR = 4.19; P = 0.01, AWAD: OR = 3.09; P = 0.02), and mortality within one-year (NA: OR = 4.19; P = 0.01, AWAD: OR = 3.09; P = 0.02). AWAD status was also associated with increased risk of hospital readmission (OR = 2.89; P < 0.001) within 30-days and any amputation (OR = 1.73; P = 0.01) within 1 year. In patients with DFUs, NA and AWAD status were predictive of major amputation during hospitalization and are associated with poorer 1-year outcomes, including mortality. Ambulatory status assessment may be used to inform DFU treatment approaches.

Predisposal factors leading to early re-amputation among diabetic patients who underwent minor amputation

Background/Aim: Prolonged wound complications and the possibility of reoperations are significant outcomes following minor amputations. As time progresses after the initial surgery, re-amputations become more prevalent. Contrary to prevailing beliefs, the incidence of early amputations remains consistent. Additionally, it is widely acknowledged that the first 6 months following the initial surgery pose the highest risk period for reoperation. This retrospective clinical study aims to investigate the risk factors contributing to ipsilateral re-amputation procedures within 6 months of the initial minor amputation. Methods: A retrospective cohort study was conducted involving amputee patients from 2008 to 2020. Patients with traumatic events, musculoskeletal tumors, prior major amputations, and those who underwent soft tissue procedures such as debridement, incision, drainage, or secondary closure were excluded. Patients who had undergone preoperative lower limb arterial Doppler ultrasound and whose initial preoperative laboratory records were accessible were included. The total cohort comprised 168 patients, comprising 57 women and 109 men. The mean follow-up duration was 1.5 years (range: 1.1–3.2 years). Patients who underwent ipsilateral re-amputation were categorized into two groups based on the timing of the subsequent surgery. The first group comprised 110 (65.5%) patients who underwent ipsilateral re-amputation 6 months after the initial amputation, while the second group encompassed 58 (34.5%) patients who underwent ipsilateral re-amputation within 6 months of the initial amputation. Results: Among the 168 patients, 58 (34.5%) experienced ipsilateral re-amputation within 6 months of their initial minor amputations, while 64.5% underwent re-amputation surgery after the initial 6 months. The absence of peripheral arterial disease was not linked to early re-amputations (P=0.001). Although the mean C-reactive protein values (80.30 mg/dL and 84.26 mg/dL for groups 1 and 2, respectively) did not display significance between the groups (P=0.40), the group undergoing amputation within 6 months demonstrated significance with elevated serum white blood cell mean levels (10.44 mcL and 11.96 mcL for groups 1 and 2, respectively; [P=0.004]). Moreover, lower hemoglobin levels (11.41 g/dL and 10.77 g/dL for groups 1 and 2, respectively) were associated with re-amputation within the initial 6 months following the initial surgery (P=0.024). Conclusion: The study underscores that the incidence of re-amputation after minor amputations in diabetic patients is comparably high, as has been reported in recent literature. While the selection of the initial amputation level remains pivotal, and not all patient-specific factors were examined in this study, the research brings attention to specific laboratory values and the vascular status of the diabetic limb as crucial considerations for surgeons prior to the initial surgery.

A study to assess the efficacy of local applicants to prevent complications of diabetic foot

Background: Diabetes is one of the most common comorbid illnesses in our community. Diabetes is associated with numerous complications related to microvascular, macrovascular, and metabolic etiologies. One of its complications in long course is diabetic foot ulcer and the associated morbidity and mortality is a major health issue. Aims and Objectives: This study was conducted to describe the lesions we treat, study and compare outcomes and to identify measures to decrease morbidity and mortality due to diabetic foot disease. Materials and Methods: All patients who attended general surgery outpatient department at M.Y. Hospital (M.P.) India between July 1st 2021 and June 30th, 2022 were included in this study with nonhealing Diabetic foot Ulcer Wagners Stage 3 for more than 2 weeks without any other comorbidities. Results: Majority of the patients presented with higher grade and with poor glycemic control at the time of presentation. Conservative management with antibiotics was useful in a small subset of the patients. Majority of the patients needed surgical treatment in the form of debridement to amputations. Conclusion: Diabetic limb disease is more prevalent in male sex commonly in 51–60 years of age group. 74% of patients presented with foot ulcer and Staphylococcus aureus was found the most common microorganism in pus culture from wounds. Local applicants are effective in controlling ulcers. In our study, hydrogel with colloidal silver was most effective followed by silver nitrate. Early and aggressive treatment of these ulcers can prevent the rate of amputation.

Getting a Foothold on Diabetic Foot Disease-Outcomes of a Multidisciplinary Clinical Pathway for Inpatient Diabetic Foot Care: A 17-Year Institutional Review.

Diabetes foot disease (DFD) contributes to poor quality of life, clinical and economic burden. Multidisciplinary diabetes foot teams provide prompt access to specialist teams thereby improving limb salvage. We present a 17-year review of an inpatient multidisciplinary clinical care path (MCCP) for DFD in Singapore. This was a retrospective cohort study of patients admitted for DFD and enrolled in our MCCP to a 1700-bed university hospital from 2005 to 2021. There were 9279 patients admitted with DFD with a mean of 545 (±119) admissions per year. The mean age was 64 (±13.3) years, 61% were Chinese, 18% Malay and 17% Indian. There was a higher proportion of Malay (18%) and Indian (17%) patients compared to the country's ethnic composition. A third of the patients had end stage renal disease and prior contralateral minor amputation. There was a reduction in inpatient major lower extremity amputation (LEA) from 18.2% in 2005 to 5.4% in 2021 (odds ratio 0.26, 95% confidence interval 0.16-0.40, P < .001) which was the lowest since pathway inception. Mean time from admission to first surgical intervention was 2.8 days and mean time from decision for revascularization to procedure was 4.8 days. The major-to-minor amputation rate reduced from 1.09 in 2005 to 0.18 in 2021, reflecting diabetic limb salvage efforts. Mean and median length of stay (LOS) for patients in the pathway was 8.2 (±14.9) and 5 (IQR = 3) days, respectively. There was a gradual trend of increase in the mean LOS from 2005 to 2021. Inpatient mortality and readmission rate was stable at 1% and 11%. Since the institution of a MCCP, there was a significant improvement in major LEA rate. An inpatient multidisciplinary diabetic foot care path helped to improve care for patients with DFD.

Abstract 546: MicroRNA-1282 As A Cis-Antisense Regulator Of Angiogenesis In Diabetic Critical Limb Ischemia

Introduction: Peripheral artery disease (PAD) is an atherosclerotic occlusive disease that leads to reduced blood flow to the lower extremities and endothelial dysfunction. Some patients develop critical limb ischemia (CLI), a severe manifestation of PAD defined as chronic ischemic rest pain with higher risk of amputation. Major risk factors for both PAD and CLI is type 2 diabetes. However, the pathophysiological contribution of microRNAs (miRNAs), in diabetic CLI progression remains poorly elucidated. Methods: By overlapping plasma miRNA sequencing in PAD patients that develop CLI with a mouse model, miRNAs were identified in the progression of diabetic limb ischemia. In this study, we describe miR-1282, a previously uninvestigated miRNA that was the highest upregulated miRNA in high-risk diabetic CLI human subjects. Results: Preliminary studies uncover a mouse ortholog of human miR-1282, a cis-antisense miRNA, that strongly inhibits the expression of SERF2 (small EDRK-rich factor 2), a protein-coding gene located on the opposite DNA strand in both human and mouse endothelial cells. SERF2 is predicted to affect the formation of aggresomes, the inclusion bodies of misfolded proteins; however, its molecular function is also poorly understood. MiR-1282 expression was decreased by diabetic stimuli such as hypoxia and glucose; and its expression inversely correlated with SERF2 expression in endothelial cells. Our in vitro studies indicate that miR-1282 mimic overexpression or SERF2 siRNA-mediated inhibition reduced a range of endothelial angiogenic assays and inhibits apoptosis. Proteomics by tandem mass-tag mass-spectrometry and transcriptomics by RNA-Seq suggest that miR-1282 likely regulates protein quality control system (SERF2, BAG1, BAG3, and HSPB8) and regulated cell death (CASP3, SLC7A11, and CTH), among others. Intriguingly, intramuscular administration of miR-1282 significantly improved blood flow recovery by laser doppler imaging in the hindlimbs of diabetic db/db mice compared to control injected mice. Conclusion: Taken together, the cis-antisense regulatory network of miR-1282-SERF2 axis reveals novel insights in the progression of diabetic CLI.

The promotion action of AURKA on post-ischemic angiogenesis in diabetes-related limb ischemia

BackgroundDiabetes-related limb ischemia is a challenge for lower extremity amputation. Aurora Kinase A (AURKA) is an essential serine/threonine kinase for mitosis, while its role in limb ischemia remains unclear.MethodHuman microvascular endothelial cells (HMEC-1) were cultured in high glucose (HG, 25 mmol/L d-glucose) and no additional growth factors (ND) medium to mimic diabetes and low growth factors deprivation as in vitro model. Diabetic C57BL/6 mice were induced by streptozotocin (STZ) administration. After seven days, ischemia was surgically performed by left unilateral femoral artery ligation on diabetic mice. The vector of adenovirus was utilized to overexpress AURKA in vitro and in vivo.ResultsIn our study, HG and ND-mediated downregulation of AURKA impaired the cell cycle progression, proliferation, migration, and tube formation ability of HMEC-1, which were rescued by overexpressed AURKA. Increased expression of vascular endothelial growth factor A (VEGFA) induced by overexpressed AURKA were likely regulatory molecules that coordinate these events. Mice with AURKA overexpression exhibited improved angiogenesis in response to VEGF in Matrigel plug assay, with increased capillary density and hemoglobin content. In diabetic limb ischemia mice, AURKA overexpression rescued blood perfusion and motor deficits, accompanied by the recovery of gastrocnemius muscles observed by H&E staining and positive Desmin staining. Moreover, AURKA overexpression rescued diabetes-related impairment of angiogenesis, arteriogenesis, and functional recovery in the ischemic limb. Signal pathway results revealed that VEGFR2/PI3K/AKT pathway might be involved in AURKA triggered angiogenesis procedure. In addition, AURKA overexpression impeded oxidative stress and subsequent following lipid peroxidation both in vitro and in vivo, indicating another protective mechanism of AURKA function in diabetic limb ischemia. The changes in lipid peroxidation biomarkers (lipid ROS, GPX4, SLC7A11, ALOX5, and ASLC4) in in vitro and in vivo were suggestive of the possible involvement of ferroptosis and interaction between AUKRA and ferroptosis in diabetic limb ischemia, which need further investigation.ConclusionsThese results implicated a potent role of AURKA in diabetes-related impairment of ischemia-mediated angiogenesis and implied a potential therapeutic target for ischemic diseases of diabetes.

Assessment of surgical management of diabetic limb complications among patients

Background: Diabetes has proved itself to be a silent killer disease. It has been estimated that there are more than two hundred million diabetics in the world. The present study was conducted to assess surgical management of diabetic limb complications among patients.Materials &amp; Methods: 62 cases of diabetic limb of both genders were enrolled. Parameters such as causes of diabetic limb, family history, type of bone involvement, type of lesions, and treatment modalities were recorded.Results: Out of 62 patients, males were 38 and females were 24. Precipitating causes were trauma in 18, infected nail bed/Fissure in 8, spontaneous in 36. In 22 cases, there was bone involvement, type of lesions was septic in 46 and ischaemic in 16. Site was leg in 20, thigh in 10 and foot in 32. Appearancewas ulcer in 30, abscess in 14, cellulitisin 8 and gangrene in 10 cases. The difference was significant (P&lt; 0.05). Treatment modality used was incision &amp;drainage in 12, debridement in 26, above knee amputation in 5, below knee amputation in 4, disarticulation of the toes in 6 and grafting in 9 cases. The difference was significant (P&lt; 0.05).Conclusion: Most common appearance of diabetic limb was ulcer and the most commonly involved site was foot. Precipitating causes were trauma, infected nail bed/Fissure and spontaneous.

A chromatin signature by the methyltransferase SETD7 orchestrates angiogenic response in diabetic limb ischemia

Abstract Background Peripheral artery disease (PAD) is highly prevalent in patients with diabetes (DM) and associates with a high rate of limb amputation and poor prognosis. Surgical and catheter-based revascularization have failed to improve outcome in DM patients with PAD. Hence, a need exists to develop new treatment strategies able to promote blood vessel growth in this setting. Mono-methylation of histone 3 at lysine 4 (H3K4me1) – a specific epigenetic signature induced by the histone methyltransferase SETD7 – favours an open chromatin thus enabling gene transcription. Purpose To investigate whether SETD7-dependent epigenetic changes modulate angiogenic response in diabetes. Methodology Primary human aortic endothelial cells (HAECs) were exposed to normal glucose (NG, 5 mM) or high glucose (HG, 25 mM) concentrations for 48 hours. Unbiased gene expression profiling was performed by RNA sequencing (RNA-seq) followed by Ingenuity Pathway Analysis (IPA). In vitro assays, namely cell migration and tube formation were employed to study angiogenic properties in HAECs. SETD7 and H3K4me1 levels were investigated by Western blot and Chromatin immunoprecipitation (ChIP). Pharmacological blockade of SETD7 was achieved by using the highly selective inhibitor (R)-PFI-2. Mice with streptozotocin-induced diabetes were orally treated with (R)-PFI-2 or vehicle and underwent hindlimb ischemia by femoral artery ligation for 14 days. Blood flow recovery was analysed at 30 minutes, 7 and 14 days by laser Doppler imaging. Our experimental findings were also translated in gastrocnemius muscle samples from patients with and without diabetes. Results RNA-seq in HG-treated HAECs revealed a profound upregulation of the methyltransferase SETD7, an enzyme involved in mono-methylation of lysine 4 at histone 3 (H3K4me1). SETD7 upregulation in HG-treated HAECs was associated with increased H3K4me1 levels as well as with impaired endothelial cell migration and tube formation. Both SETD7 gene silencing and pharmacological inhibition by (R)PFI-2 rescued hyperglycemia-induced impairment of HAECs migration and tube formation, while SETD7 overexpression blunted the angiogenic response. RNA-seq and ChIP assays showed that SETD7-dependent H3K4me1 regulates the transcription of the angiogenesis inhibitor semaphorin-3G (SEMA-3G). Moreover, SEMA-3G overexpression blunted migration and tube formation in SETD7-depleted HAECs. In diabetic mice with hindlimb ischemia, treatment with (R)-PFI-2 improved limb vascularization and perfusion as compared to vehicle. Finally, SETD7/SEMA3G axis was upregulated in muscle specimens from T2D patients as compared to controls. Conclusion Targeting SETD7 represents a novel epigenetic-based therapy to boost neovascularization in diabetic patients with PAD. Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): University of Zurich - Forshungskredit candoc grant

Nrf2 transcriptional upregulation of IDH2 to tune mitochondrial dynamics and rescue angiogenic function of diabetic EPCs

Endothelial progenitor cells (EPCs) are reduced in number and impaired in function in diabetic patients. Whether and how Nrf2 regulates the function of diabetic EPCs remains unclear. In this study, we found that the expression of Nrf2 and its downstream genes were decreased in EPCs from both diabetic patients and db/db mice. Survival ability and angiogenic function of EPCs from diabetic patients and db/db mice also were impaired. Gain- and loss-of-function studies, respectively, showed that knockdown of Nrf2 increased apoptosis and impaired tube formation in EPCs from healthy donors and wild-type mice, while Nrf2 overexpression decreased apoptosis and rescued tube formation in EPCs from diabetic patients and db/db mice. Additionally, proangiogenic function of Nrf2-manipulated mouse EPCs was validated in db/db mice with hind limb ischemia. Mechanistic studies demonstrated that diabetes induced mitochondrial fragmentation and dysfunction of EPCs by dysregulating the abundance of proteins controlling mitochondrial dynamics; upregulating Nrf2 expression attenuated diabetes-induced mitochondrial fragmentation and dysfunction and rectified the abundance of proteins controlling mitochondrial dynamics. Further RNA-sequencing analysis demonstrated that Nrf2 specifically upregulated the transcription of isocitrate dehydrogenase 2 (IDH2), a key enzyme regulating tricarboxylic acid cycle and mitochondrial function. Overexpression of IDH2 rectified Nrf2 knockdown- or diabetes-induced mitochondrial fragmentation and EPC dysfunction. In a therapeutic approach, supplementation of an Nrf2 activator sulforaphane enhanced angiogenesis and blood perfusion recovery in db/db mice with hind limb ischemia. Collectively, these findings indicate that Nrf2 is a potential therapeutic target for improving diabetic EPC function. Thus, elevating Nrf2 expression enhances EPC resistance to diabetes-induced oxidative damage and improves therapeutic efficacy of EPCs in treating diabetic limb ischemia likely via transcriptional upregulating IDH2 expression and improving mitochondrial function of diabetic EPCs.

Abstract P3011: Nrf2 Transcriptional Upregulation Of Idh2 To Tune Mitochondrial Dynamics And Rescue Angiogenic Function Of Diabetic Epcs

Endothelial progenitor cells (EPCs) are reduced in number and impaired in function in diabetic patients. Whether and how Nrf2 regulates the function of diabetic EPCs remains unclear. In this study, we found that the expression of Nrf2 and its downstream genes were decreased in EPCs from both diabetic patients and db/db mice. Survival ability and angiogenic function of EPCs from diabetic patients and db/db mice also were impaired. Gain- and loss-of-function studies, respectively, showed that knockdown of Nrf2 increased apoptosis and impaired tube formation in EPCs from healthy donors and wild-type mice, while Nrf2 overexpression decreased apoptosis and rescued tube formation in EPCs from diabetic patients and db/db mice. Additionally, proangiogenic function of Nrf2-manipulated mouse EPCs was validated in db/db mice with hind limb ischemia. Mechanistic studies demonstrated that diabetes induced mitochondrial fragmentation and dysfunction of EPCs by dysregulating the abundance of proteins controlling mitochondrial dynamics; upregulating Nrf2 expression attenuated diabetes-induced mitochondrial fragmentation and dysfunction and rectified the abundance of proteins controlling mitochondrial dynamics. Further RNA-sequencing analysis demonstrated that Nrf2 specifically upregulated the transcription of isocitrate dehydrogenase 2 (IDH2), a key enzyme regulating tricarboxylic acid cycle and mitochondrial function. Overexpression of IDH2 rectified Nrf2 knockdown- or diabetes-induced mitochondrial fragmentation and EPC dysfunction. In a therapeutic approach, supplementation of an Nrf2 activator sulforaphane enhanced angiogenesis and blood perfusion recovery in db/db mice with hind limb ischemia. Collectively, these findings indicate that Nrf2 is a potential therapeutic target for improving diabetic EPC function. Thus, elevating Nrf2 expression enhances EPC resistance to diabetes-induced oxidative damage and improves therapeutic efficacy of EPCs in treating diabetic limb ischemia likely via transcriptional upregulation of IDH2 expression and improving mitochondrial function of diabetic EPCs.

Wellness for the Wounded: Mental Health Care in the Diabetic Limb Salvage Team.

Managing patients with diabetic foot ulcers mandates coordinated input from multiple disciplines. Our practice has published previously on the value of a multidisciplinary team, incorporating skills from plastic surgery, vascular surgery, podiatry, rheumatology, and hyperbaric oxygen therapy in a single location.1 A relatively underdiscussed and poorly recognized component of the multidisciplinary team is mental health care through psychiatrists and psychosocial support. The effects of acute and chronic wound formation on a patient’s quality of life are well documented. Much of the literature comes from studies on trauma and burn survivors. In these fields, preexisting mental health conditions have been linked to higher rates of reoperation, longer hospital stays, and longer times to return to preinjury activity.2 More recently, validated surveys that assess emotional quality of life, such as the 36-Item Short-Form Health Survey, have been applied to the chronic wound populations.3 Patients with chronic leg ulcers have the highest rates of depression among patients with skin diseases and consistently report lower quality of life, worse physical functioning, and higher levels of pain.4 However, few studies comment on the critical role of psychiatrists, psychologists, and social support in the chronic wound population. In the chronic wound population, the interplay of mental health and wound-related outcomes is critical. Chronic diseases, such as diabetes, require lifelong maintenance therapy and diligent monitoring for acute emergencies. Patients who have difficulty adapting to their intensive medically necessary care face higher disease burden and are at risk for experiencing the extremes of disease progression, such as limb loss. Research shows that patients with high mental illness burden often have difficulty adhering to medication schedules. Patients who are prescribed psychiatric medication take, on average, 58 to 65 percent of all prescribed medications.5 Patients with chronic wounds and diabetic foot ulcers are seen bimonthly to weekly by a team of specialized wound care physicians who are not trained to recognize or manage psychiatric disease. Adding psychiatry or behavioral psychology to the wound team provides critical services that allow for prompt identification of disease. Incorporating providers who are equipped to manage physical and mental aspects of care is essential to improve health outcomes and reduce health care costs. To accomplish this goal, all centers that provide care for patients with diabetic wounds can (1) incorporate a dedicated expert in mental health on their team, (2) consistently refer all diabetic wound patients who are exhibiting signs of mental health distress to a behavioral health specialist, (3) educate existing staff members on the role of mental health in wound healing, and (4) screen patients for depression and anxiety during all stages of care. There is abundant need for research into the relationship between successful chronic wound management and mental health support. More longitudinal analyses of the development of new or progression of preexisting psychiatric conditions as a consequence of chronic wound formation will help guide treatment of coexisting conditions. Quality trials also need to assess which behavioral or pharmacologic treatments yield the greatest benefit to wound healing and functional outcomes. DISCLOSURE The authors have no financial interest to declare in relation to the content of this article.

A Study of Vacuum Assisted Closure Dressing in 50 Cases of Patients of Diabetic Limb

Background: To evaluate the effectiveness of VAC dressing for the management of diabetic limb. Material and Method: The study is a prospective comparative study which was conducted on 50 patients of diabetic limb ulcers admitted in General Surgery Department at Tertiary care hospital between June 2017 to June 2019. Patients were followed up until discharged from the hospital or completion of 8 weeks assessment period from the date of admission whichever was earlier. Result: Ulcer due to diabetes is common in males. 4% of the patients had hba1c level between 6.5 to 9.5. In 64% of patients granulation tissue appeared at the end of 2 weeks after VAC dressing while in only 40% of patients granulation tissue appeared after 2 weeks of conventional dressing. In 80% of patients wound was completely covered by granulation tissue at the end of 4 weeks after VAC dressing while only in 52% wound was completely covered by granulation tissue after 4 weeks of conventional dressing. Conclusion: VAC therapy is better than conventional therapies in terms of wound healing, less complications, reducing the hospital stay, reducing the bacterial infection load and is cost effective. Keywords: - VAC Therapy, diabetes, granulation tissue

A Retrospective Case Series on Free Flap Reconstruction for Ischemic Diabetic Foot: The Nutrient Flap Further Explained.

This retrospective case series compares the outcomes and postoperative oxygen levels in patients who underwent free flap versus primary closure/local flap reconstruction for ischemic diabetic foot wounds to determine the influence of free flap on the surrounding ischemic tissues. The authors hypothesized that the free flap would benefit the surrounding ischemic tissue as a nutrient flap by increasing the tissue oxygen content. The patients were divided into two groups: group 1 underwent free flap reconstruction, and group 2 underwent partial foot amputation with primary closure/local flap. Patient demographics, endovascular intervention, surgical outcome, postreconstruction intervention, and prereconstruction and postreconstruction transcutaneous oximetry were analyzed. Among 54 patients, 36 were in group 1 and 18 were in group 2. There were no differences in patient demographics between the two groups. All patients had successful angioplasty. Statistical significance was noted in postreconstruction intervention in which group 2 required 2.8 ± 2.9 débridements (versus 1.2 ± 2.5 for group 1) and seven of 18 below-knee amputations (versus three of 36 for group 1) (p < 0.05). Transcutaneous partial pressure of oxygen levels were significantly higher in group 1 at 6 months after reconstruction (61.6 ± 7.5 versus 32.6 ± 5.8 mmHg) (p < 0.01). This study shows that the role of the free flap in ischemic diabetic limb may expand beyond that of providing coverage over the vital structures, and it supports the use of the free flap as a nutrient to increase oxygen content in the ischemic diabetic foot. Therapeutic, III.

Characterization of inflammatory profiles and endothelial dysfunction in diabetic limb arterial occlusion

Characterization of inflammatory profiles and endothelial dysfunction in diabetic limb arterial occlusion

Comparative Doppler Ultrasound Findings of Foot Arteries in Patients with Type 2 Diabetes Mellitus and Normoglycaemic Patients

Aim of the Study:The aim of this study was to investigate lower extremity peripheral artery disease (LEPAD) in the foot arteries of patients with type 2 diabetes mellitus, with and without clinical symptoms of arterial insufficiency, using triplex Doppler ultrasound.Materials and Methods:Forty-seven consecutive adult subjects with type 2 diabetes mellitus (T2DM) and 47 age-matched and sex-matched non-diabetic controls were recruited (94 limbs each). Ankle-brachial index (ABI), fasting blood glucose assay, glycated haemoglobin assay and triplex sonography of the dorsalis pedis artery (DPA) and the distal posterior tibial artery (PTA) in both feet were performed.Results:The mean age of the subjects and controls were 60.21 ± 7.68 years and 56.81 ± 9.05 years (P > 0.05). The mean duration of diabetes mellitus was 10.4 ± 5.8 years. Crampy calf pain was the most common presenting symptom. Twenty-one (22.3%) of the 94 limbs of T2DM subjects had an abnormal ABI. Abnormal triplex Doppler waveform was seen in more than half of the PTA (57/94; 60.6%) and DPA (55/94; 58.5%). Forty-one (43.6%) of the 94 diabetic limbs had plaques in the PTA, while plaques were present in the DPA of 52 (55.3%) diabetic limbs.Conclusion:LEPAD is common in T2DM with a higher prevalence on triplex Doppler sonography compared to ABI values.

Patient-centered clinical success after lower extremity revascularization for complex diabetic foot wounds treated in a multidisciplinary setting

ObjectivePhysician-oriented outcomes, such as patency and amputation-free survival (AFS), have traditionally been markers of success after lower extremity revascularization. Previous studies have defined clinical success based on a composite of patient-centered outcomes and have shown this outcome to be achieved in less than 50% of patients, far lower than standard physician-oriented outcomes. The purpose of this study is to evaluate clinical success after lower extremity bypass (LEB) or peripheral vascular intervention (PVI) for tissue loss in diabetic patients treated in a multidisciplinary setting to better understand what factors are associated with success from a patient’s perspective. MethodsAll patients presenting to our multidisciplinary diabetic limb preservation service from July 2012 to January 2020 were enrolled in a prospective database. Patients who underwent either LEB or PVI for ulcer or gangrene were included in the analysis. Clinical success was defined as the composite outcome of secondary patency to the point of wound healing, limb salvage for 1 year, maintenance of ambulatory status for 1 year, and survival for 6 months. Secondary outcomes included 1-year wound healing, patency, and AFS. ResultsA total of 134 revascularizations were performed in 131 patients, including 91 (68%) PVI and 43 (32%) LEB. Patients were more frequently male (64%) and black (61%), and 16% were dialysis-dependent. All patients had tissue loss (53% ulcer, 47% gangrene). There were 5 (3.7%) wound, ischemia, and foot infection stage 1, 6 (6.0%) stage 2, 29 (22%) stage 3, and 92 (69%) stage 4 limbs at the time of revascularization. Overall, 76.9% of patients preserved secondary patency to the point of wound healing, 92.5% had limb salvage for 1 year, 90.3% had maintenance of ambulatory status for 1 year, and 96.3% survived for 6 months. The clinical success composite outcome was achieved in 71.6% of patients and was not statistically different between those undergoing PVI vs LEB (69.2% vs 76.7%, P = .37). Secondary patency, limb salvage, and AFS at 1 year were 80.8% ± 3.6%, 91.8% ± 2.3%, and 83.3% ± 3.1%, respectively. Wound healing at 1 year was 84.3% ± 3.4%. The only covariate associated with clinical failure on multivariable analysis was increased age (odds ratio, 0.95; 95% confidence interval, 0.91-0.99; P = .008). ConclusionsAmong diabetic patients presenting with tissue loss, the composite outcome of patient-centered clinical success is lower than traditional physician-centered outcomes after lower extremity revascularization, mostly due to low rates of secondary patency to the point of wound healing. In the current study, clinical failure was only associated with older age and was no different after PVI compared with LEB.