Peripheral arterial disease in diabetes--a review

Analysis of factors influencing the recurrence of diabetic foot ulcers

OBJECTIVE

The aim of this study is to investigate the factors influencing the recurrence of diabetic foot ulcers (DFU) and provide guidance for reducing the recurrence rate.

METHODS

A total of 211 patients diagnosed with DFU who were hospitalized and discharged from the hospital from October 2015 to January 2020 were included as the study cohort. Participants were divided into two groups according to whether the foot ulcer recurred during the 2-year follow-up period: a recurrence group (n = 84) and a non-recurrence group (n = 127). The following data were collected and analyzed for the two groups of patients: general information, foot information, laboratory indicators, diabetes comorbidities, and complications.

RESULTS

(1) The overall recurrence rate of diabetic foot ulcers (DFU) within 2 years was 39.8%, indicating a high recurrence rate. (2) Significant differences were observed between the two patient groups in terms of BMI, HbA1c, TBIL, CRP, financial situation, foot deformity, first ulcer on the sole of the foot, previous amputation history, Wagner grade of the first ulcer, osteomyelitis, DFU duration (>60 days), lower limb vascular reconstruction, peripheral arterial disease (PAD), and diabetic peripheral neuropathy (DPN) (t = 2.455; Z = -1.988, -3.731, -3.618; χ2 = 7.88, 5.004, 3.906, 17.178, 16.237, 5.007, 24.642, 4.782, 29.334, 10.253). No significant differences were found for the other indicators. (3) Logistic regression analysis revealed that TBIL (OR = 0.886, p = 0.036) was a protective factor against ulcer recurrence. In contrast, PAD, previous amputation history, DPN, and the first ulcer on the sole of the foot (OR = 3.987, 6.758, 4.681, 2.405; p < 0.05 or p < 0.01) were identified as risk factors for ulcer recurrence.

CONCLUSION

Early screening and preventive education targeting high-risk factors such as DPN, PAD and the initial ulcer location on the sole of the foot are essential to mitigate the high long-term recurrence rate of DFU. Furthermore, the protective role of TBIL in preventing ulcer recurrence underscores the importance of monitoring bilirubin levels as part of a comprehensive management strategy for DFU patients.

High ankle-brachial index participants experienced similar long-term mortality as peripheral artery disease in a national sample of community-dwelling adults

BACKGROUND

Only a few small studies have shown the association between high ankle-brachial pressure index (ABI >1.4) and adverse cardiovascular (CV) events and mortality. Although there is abundant literature depicting the association between ABI and overall systemic atherosclerosis, it typically focuses on low ABI. Furthermore, historically, many studies focusing on peripheral artery disease have excluded high ABI participants. We aimed to study the mortality outcomes of persons with high ABI in the National Health and Nutrition Examination Survey (NHANES).

METHODS

We obtained ABI from participants aged ≥40 years for survey years 1999 to 2004. We defined low a ABI as ≤0.9, normal ABI as 0.9 to 1.4, and high ABI as >1.4 or if the ankle pressures were >245 mm Hg. Demographics, various comorbidities, and laboratory test results were obtained at the time of the survey interview. Multivariable adjusted hazard ratios (HRs) along with 95% confidence intervals (CIs) were calculated for CV and all-cause mortality via Cox proportional hazards regression. Mortality was linked to all NHANES participants for follow-up through December 31, 2019, by the Centers for Disease Control and Prevention.

RESULTS

We identified 7639 NHANES participants with available ABI. Of these, 6787 (89%) had a normal ABI, 646 (8%) had a low ABI, and 206 (3%) had elevated ABI. Of participants with high ABI, 50% were men, 15% were African Americans, 10% were current smokers, 56% had hypertension, 33% had diabetes, 15% had chronic kidney disease (CKD), and 18% had concomitant coronary artery disease (CAD). Diabetes (odds ratio [OR], 2.4; 95% CI, 1.7-3.2), CAD (OR, 1.6; 95% CI, 1.0-2.4), and CKD (OR, 1.5; 95% CI, 1.0-2.3) at baseline were associated with having a high ABI, respectively. A high ABI was associated independently with elevated CV (HR, 2.6; 95% CI, 2.1-3.1; P < .0001) and all-cause mortality (HR, 2.5; 95% CI, 2.2-2.8; P < .0001) after adjusting for covariates, including diabetes, CKD, CAD, current smoking, cancer, and hypertension.

CONCLUSIONS

A high ABI is associated with an elevated CV and all-cause mortality, similar to patients with PAD. High ABI participants should receive the same attention and aggressive medical therapies as patients with PAD.

A portable optical pulsatile flowmetry demonstrates strong clinical relevance for diabetic foot perfusion assessment

We present a robust, cost-effective (<2000 USD), and portable optical diffuse speckle pulsatile flowmetry (DSPF) device with a flexible handheld probe for deep tissue blood flow measurement in the human foot as well as a first-in-man observational clinical study using the proposed optical device for tissue ischemia assessment and peripheral artery disease (PAD) diagnosis. Blood flow in tissue is inherently pulsatile in nature. However, most conventional methods cannot measure deep tissue-level pulsatile blood flow noninvasively. The proposed optical device can measure tissue-level pulsatile blood flow ∼6 mm underneath the skin surface. A new quantitative tissue perfusion index (TPIDSPF) based on frequency domain analysis of the pulsatile blood flow waveform is defined to assess tissue ischemia status. Through a clinical study involving 66 subjects, including healthy individuals and diabetes patients with and without PAD, TPIDSPF demonstrated strong correlations of 0.720 with transcutaneous tissue partial oxygen pressure (TcPO2) and 0.652 with toe-brachial index (TBI). Moreover, among the three methods, TPIDSPF demonstrated the highest area under the curve for PAD diagnosis among diabetes patients, with a notable value of 0.941. The promising clinical results suggest that the proposed optical method has the potential to be an effective clinical tool for identifying PAD among the diabetic cohort.

Longitudinal Magnetic Resonance Imaging-Based Superficial Femoral Artery Velocity Measurements in Diabetic and Nondiabetic Patients With Peripheral Artery Disease

BACKGROUND

Longitudinal associations of noninvasive 2-dimensional phase-contrast magnetic resonance imaging (2D-PC-MRI) velocity markers of the superficial femoral artery (SFA) were analyzed along with the characteristics of peripheral artery disease (PAD). We hypothesized that the 2-year differences in MRI-based measures of SFA velocity were associated with longitudinal changes in markers of PAD.

METHODS

A total of 33 (11 diabetic, 22 nondiabetic) patients with PAD with baseline and 2-year follow-up MRI scans were included in this secondary analysis of the Effect of Lipid Modification on Peripheral Artery Disease after Endovascular Intervention Trial (ELIMIT). Electrocardiographically gated 2D-PC-MRI was performed at a proximal and a distal location of the distal SFA territory. SFA lumen, wall, and total vessel volumes and the normalized wall index (NWI) were analyzed.

RESULTS

Baseline characteristics did not differ between diabetic and nondiabetic PAD patients. Maximum proximal and distal SFA velocity measures did not differ between baseline and 2 years (41.98 interquartile range (IQR) (23.58-72.6) cm/s vs. 40.31 IQR (26.69-61.29) cm/s; P = 0.30). Pooled analysis (N = 33) showed that the 24-month change in the NWI was inversely associated with the 24-month change in the proximal maximal SFA velocity (beta = -168.36, R2 = 0.150, P value = 0.03). The 24-month change of the maximum velocity differences between the proximal and distal SFA locations was inversely associated with the 24-month changes in peak walking distance (beta = -0.003, R2 = 0.360, P value = 0.011).

CONCLUSION

The 2-year change of SFA plaque burden is inversely associated with the 2-year change of proximal peak SFA blood flow velocity. 2D-PC-MRI measured SFA velocity may be of interest in assessing PAD longitudinally.

Analysis of Lower Extremity Amputations from the SerbVasc Registry

BACKGROUND

Peripheral arterial disease (PAD) and diabetes are the major causes of lower extremity amputations (LEAs) worldwide. Morbidity and mortality in patients with LEAs are high with an associated significant burden on the global health system. The aim of this article is to report the overall morbidity and mortality rates after major and minor LEAs from the Serbian Vascular Registry (SerbVasc), with an analysis of predictive factors that influenced adverse outcomes.

MATERIALS AND METHODS

SerbVasc was created in 2019 as a part of the Vascunet collaboration that is aiming to include all vascular procedures from 21 hospitals in Serbia. Prevalence of diabetes among patients with LEAs, previous revascularization procedures, the degree and the type of foot infection and tissue loss, and overall morbidity and mortality rates were analyzed, with a special reference to mortality predictors.

RESULTS

In the period from January 2020 to December 2022, data on 702 patients with LEAs were extracted from the SerbVasc registry, mean age of 69.06±10.63 years. Major LEAs were performed in 59%, while minor LEAs in 41% of patients. Diabetes was seen in 65.1% of the patients, with 44% of them being on insulin therapy. Before LEA, only 20.3% of patients had previous peripheral revascularization. Soft tissue infection, irreversible acute ischemia, and Fontaine III and IV grade ischemia were the most common causes of above-the-knee amputations while diabetic foot was the most common cause of transphalangeal and toe amputations. The infection rate was 3.7%, the re-amputation rate was 5.7%, and the overall mortality rate was 6.9%, with intrahospital mortality in patients with above-the-knee amputation of 11.1%. The most significant intrahospital mortality predictors were age >65 years (p<0.001), chronic kidney disease (CKD) (p<0.001), ischemic heart disease (IHD) (p=0.001), previous myocardial revascularization (p=0.017), emergency type of admission (p<0.001), not using aspirin (p=0.041), using previous anticoagulation therapy (p=0.003), and postoperative complications (p<0.001).

CONCLUSIONS

The main predictors of increased mortality after LEAs from the SerbVasc registry are age >65 years, CKD, IHD, previous myocardial revascularization, emergency type of admission, not using aspirin, using previous anticoagulation therapy, and postoperative complications. Taking into account high mortality rates after LEAs and a small proportion of previous peripheral revascularization, the work should be done on early diagnosis and timely treatment of PAD hopefully leading to decreased number of LEAs and overall mortality.

CLINICAL IMPACT

Mortality after lower limb amputation from the SerbVasc register is high. A small number of previously revascularized patients is of particular clinical importance, bearing in mind that the main reasons for above-the-knee amputations were irreversible ischemia, Fontaine III and Fontaine IV grade ischemia. Lack of diagnostics procedures and late recognition of patients with PAD, led to subsequent threating limb ischemia and increased amputation rates. The work should be done on early diagnosis and timely treatment of PAD in Serbia, hopefully leading to an increased number of PAD procedures, decreased number of LEAs, and lower overall mortality.

Angiogenic and Microvascular Status Alterations after Endovascular Revascularization of Lower Limb Arteries among Patients with Diabetic Foot Syndrome: A Prospective 12-Month Follow-Up Study

Peripheral arterial disease (PAD)-induced ischemia is an important component of diabetic foot syndrome (DFS). The results of revascularization of the lower extremity arteries (including percutaneous transluminal angioplasty [PTA]) do not always give satisfactory long-term results, which is due to many factors. The aim of the study was to investigate the alterations in selected circulating angiogenic factors and microcirculation parameters in 41 patients with DFS following PTA and analyze their relationships with clinical outcomes during 1-year follow-up. Our study revealed a general decrease in pro-angiogenic factor levels after PTA and their subsequent stabilization during subsequent observation. The results indicated a significant association between plasma circulating FGF-2 level and poor outcomes (including the incidence of restenosis/reocclusion of treated arteries) during 12 months of observation. The perioperative changes in FGF-2 showed a significant association with LDF alterations after PTA. Follow-up 1-3 months post-intervention showed a tendency towards elevated TcpO2, VEGF-A, and VEGF-R2 levels in patients free from adverse events. These results may provide a basis for further research on the potential use of selected circulating angiogenic factors for monitoring the treatment of patients with DFS following PTA.

Device-measured physical activity behaviours, and physical function, in people with type 2 diabetes mellitus and peripheral artery disease: A cross-sectional study

AIM

To quantify differences in device-measured physical activity (PA) behaviours, and physical function (PF), in people with type 2 diabetes mellitus (T2DM) with and without peripheral artery disease (PAD).

MATERIALS AND METHODS

Participants from the Chronotype of Patients with T2DM and Effect on Glycaemic Control cross-sectional study wore accelerometers on their non-dominant wrist for up to 8-days to quantify: volume and intensity distribution of PA, time spent inactive, time in light PA, moderate-to-vigorous PA in at least 1-minute bouts (MVPA1min), and the average intensity achieved during the most active continuous 2, 5, 10, 30, and 60-minute periods of the 24-h day. PF was assessed using the short physical performance battery (SPPB), the Duke Activity Status Index (DASI), sit-to-stand repetitions in 60 s (STS-60); hand-grip strength was also assessed. Differences between subjects with and without PAD were estimated using regressions adjusted for possible confounders.

RESULTS

736 participants with T2DM (without diabetic foot ulcers) were included in the analysis, 689 had no PAD. People with T2DM and PAD undertake less PA (MVPA1min: -9.2 min [95 % CI: -15.3 to -3.0; p = 0.004]) (light intensity PA: -18.7 min [-36.4 to -1.0; p = 0.039]), spend more time inactive (49.2 min [12.1 to 86.2; p = 0.009]), and have reduced PF (SPPB score: -1.6 [-2.5 to -0.8; p = 0.001]) (DASI score: -14.8 [-19.8 to -9.8; p = 0.001]) (STS-60 repetitions: -7.1 [-10.5 to -3.8; p = 0.001]) compared to people without; some differences in PA were attenuated by confounders. Reduced intensity of activity for the most active continuous 2-30 min in the 24-h day, and reduced PF, persisted after accounting for confounders. There were no significant differences in hand-grip strength.

CONCLUSIONS

Findings from this cross-sectional study suggest that, the presence of PAD in T2DM may have been associated with lower PA levels and PF.

Enrichment of miR-17-5p enhances the protective effects of EPC-EXs on vascular and skeletal muscle injury in a diabetic hind limb ischemia model

BACKGROUND/AIMS

Diabetes mellitus (DM) is highly susceptible to diabetic hind limb ischemia (DHI). MicroRNA (MiR)-17-5p is downregulated in DM and plays a key role in vascular protection. Endothelial progenitor cell (EPC)-released exosomes (EPC-EXs) contribute to vascular protection and ischemic tissue repair by transferring their contained miRs to target cells. Here, we investigated whether miR-17-5p-enriched EPC-EXs (EPC-EXs^miR-17-5p) had conspicuous effects on protecting vascular and skeletal muscle in DHI in vitro and in vivo.

METHODS

EPCs transfected with scrambled control or miR-17-5p mimics were used to generate EPC-EXs and EPC-EXs^miR-17-5p. Db/db mice were subjected to hind limb ischemia. After the surgery, EPC-EXs and EPC-EXs^miR-17-5p were injected into the gastrocnemius muscle of the hind limb once every 7 days for 3 weeks. Blood flow, microvessel density, capillary angiogenesis, gastrocnemius muscle weight, structure integrity, and apoptosis in the hind limb were assessed. Vascular endothelial cells (ECs) and myoblast cells (C2C12 cells) were subjected to hypoxia plus high glucose (HG) and cocultured with EPC-EXs and EPC-EXs^miR-17-5p. A bioinformatics assay was used to analyze the potential target gene of miR-17-5p, the levels of SPRED1, PI3K, phosphorylated Akt, cleaved caspase-9 and cleaved caspase-3 were measured, and a PI3K inhibitor (LY294002) was used for pathway analysis.

RESULTS

In the DHI mouse model, miR-17-5p was markedly decreased in hind limb vessels and muscle tissues, and infusion of EPC-EXs^miR-17-5p was more effective than EPC-EXs in increasing miR-17-5p levels, blood flow, microvessel density, and capillary angiogenesis, as well as in promoting muscle weight, force production and structural integrity while reducing apoptosis in gastrocnemius muscle. In Hypoxia plus HG-injured ECs and C2C12 cells, we found that EPC-EXs^miR-17-5p could deliver their carried miR-17-5p into target ECs and C2C12 cells and subsequently downregulate the target protein SPRED1 while increasing the levels of PI3K and phosphorylated Akt. EPC-EXs^miR-17-5p were more effective than EPC-EXs in decreasing apoptosis and necrosis while increasing viability, migration, and tube formation in Hypoxia plus HG-injured ECs and in decreasing apoptosis while increasing viability and myotube formation in C2C12 cells. These effects of EPC-EXs^miR-17-5p could be abolished by a PI3K inhibitor (LY294002).

CONCLUSION

Our results suggest that miR-17-5p promotes the beneficial effects of EPC-EXs on DHI by protecting vascular ECs and muscle cell functions.

Positive association between urinary albumin-creatinine ratio and lower extremity peripheral arterial disease in Chinese diabetes patients: A cross-section study with propensity score matching analysis

BACKGROUND AND AIMS

Elevated urinary albumin-creatinine ratio (ACR) is an established risk factor for lower extremity peripheral arterial disease (PAD) in non-diabetes individual. This study aimed to determine the relationship between urinary ACR level and PAD in diabetes population.

METHODS AND RESULTS

A cross-section study with 1396 hospitalized diabetes participants from department of endocrinology and neurology were performed and the propensity score matching method was applied to reduce the effects of confounding factors between the matched PAD and Non-PAD groups. The relationship between urinary ACR and ankle-brachial index (ABI) was analyzed by linear curve fitting analyses and multiple logistic regression models. Our study showed that the prevalence of PAD (low ABI, ABI<0.9) was 7.09% in our diabetes patients. The ABI level was significantly lower in high ACR group compared with those in normal urinary ACR group (1.11 ± 0.17 vs 1.13 ± 0.15, p = 0.010). The prevalence of PAD was increased with the increased tertile's of log2-transformed ACR in total patients before and after propensity score matching (p < 0.001 and p = 0.007, respectively). The OR (95% CI) between log2-transformed ACR and PAD was 1.0 and 1.70 (1.08-2.69, p = 0.022) respectively in normal and high ACR levels in diabetes patients after adjusting for potential confounders. After propensity score matching, the OR (95% CI) between log2-transformed ACR and PAD was 1.0 and 1.85 (1.05-3.23, p = 0.031) respectively in normal and high ACR levels in diabetes patients after adjusting for potential confounders.

CONCLUSION

The elevated urinary ACR level was associated with PAD in Chinese diabetes patients.

Occurrence of Major Local Lower Limb Events in Type 2 Diabetic Patients with Lower Extremity Arterial Disease: Impact of Metformin

BACKGROUNDS

Patients with type 2 diabetes mellitus (T2DM) are particularly at risk of developing major adverse cardiovascular events (MACE) and peripheral artery disease (PAD) due to an acceleration of the atherosclerotic process linked to hyperglycemia and inflammation with a greater risk of local complications. We aimed to identify the predictive factors for major adverse limb events (MALE) in T2DM patients with PAD to manage modifiable factors at an early stage.

METHODS

This is a prospective study in which T2DM patients with PAD were included from November 2017 to May 2018 and followed over 12 months. The predictive factors for the onset of MALE, MACE, and death from all causes have been identified.

RESULTS

A total of 100 patients were included; 37% of the patients developed a MALE. After multivariate analysis, metformin was associated with a decrease of MALE (odds ratio (OR) = 0.26; 95% confidence interval (CI) [0.10; 0.68]; P = 0.007), and a history of the treatment of intravenous iloprost was associated with an increased risk of MALE (OR = 5.70; 95% CI [1.31; 31.93]; P = 0.029). Regular physical activity was associated with a decreased risk of MACE (OR = 0.07; 95% CI [0; 0.44]; P = 0.021). A history of stroke and a history of venous thromboembolism were associated with an increased all-cause mortality risk with OR = 3.68; 95% CI [1.17; 11.5]; P = 0.025 and OR = 3.78; 95% CI [1.16; 12.3]; P = 0.027.

CONCLUSIONS

Metformin is protective against local complications in people with diabetes with PAD and should be prescribed to diabetic patients with PAD at an early stage.

Salidroside facilitates therapeutic angiogenesis in diabetic hindlimb ischemia by inhibiting ferroptosis

Hindlimb ischemia (HLI), in which blood perfusion to the hindlimb is obstructed, is one of the major complications of diabetes. Skeletal muscle cells are crucial for revascularization as they can secrete various angiogenic factors; however, hyperglycemia impairs their viability and subsequently their angiogenic potential. Salidroside can promote skeletal muscle cell viability under hyperglycemia; however, the molecular mechanism is still poorly understood. Here we revealed that salidroside could suppress hyperglycemia-induced ferroptosis in skeletal muscle cells by promoting GPX4 expression, thereby restoring their viability and paracrine functions. These in turn promoted the proliferation and migration potentials of blood vessel-forming cells. Furthermore, we showed that salidroside/GPX4-mediated ferroptosis inhibition is crucial for promoting angiogenesis and blood perfusion recovery in diabetic HLI mice. Together, we reveal a novel molecular mechanism of salidroside in enhancing skeletal muscle cells-mediated revascularization and blood perfusion recovery in diabetic HLI mice, further highlighting it as a potential compound for treating diabetic HLI.

Evaluation of Vitamin D Levels in Patients With Diabetic Foot Ulcers

Low vitamin D levels have been associated with several diseases as its receptors are expressed in almost all tissues of the human body. Literature data have shown delayed diabetic foot ulcer (DFU) healing in patients with low vitamin D; however, data on the association between vitamin D levels and DFU in Mediterranean countries are scarce. In this cross-sectional study we examined for differences in serum vitamin D levels between patients with DFU, people with diabetes mellitus (DM) without DFU and healthy individuals in a Southern European country. A total of 96 subjects (33 patients with DFU, 35 patients without DFU and 28 healthy controls) were recruited. Medical and dietary history was obtained and total serum 25-hydroxyvitamin D [25(OH)D] levels were determined. Serum vitamin D levels differed significantly among the three groups of participants; sub-analysis showed that healthy individuals had higher vitamin D levels when compared with patients with and without DFU, while vitamin D levels did not differ between patients with and without DFU (17.9 ± 6.7 vs. 19.8 ± 8.7 ng/mL, P = 0.329, respectively). More than half of patients with DM with or without DFU had vitamin D levels <20 ng/ml. A positive correlation was found between vitamin D and sun exposure duration in participants without DFU. In conclusion, although serum vitamin D levels did not differ between people with and without DFU, the prevalence of deficiency and insufficiency was high in both groups in a Mediterranean country. This finding highlights the need for screening and supplementation with vitamin D in individuals with DM.

Liraglutide Accelerates Ischemia-Induced Angiogenesis in a Murine Diabetic Model

Background Severe hindlimb ischemia is a chronic disease with poor prognosis that can lead to amputation or even death. This study aimed to assess the therapeutic effect of liraglutide on hind-limb ischemia in type 2 diabetic mice and to elucidate the underlying mechanism. Methods and Results Blood flow reperfusion and capillary densities after treatment with liraglutide or vehicle were evaluated in a mouse model of lower-limb ischemia in a normal background or a background of streptozotocin-induced diabetes. The proliferation, migration, and tube formation of human umbilical vein endothelial cells were analyzed in vitro upon treatment with liraglutide under normal-glucose and high-glucose conditions. Levels of phospho-Akt, phospho-endothelial nitric oxide synthase, and phospho-extracellular signal-related kinases 1 and 2 under different conditions in human umbilical vein endothelial cells and in ischemic muscle were determined by western blotting. Liraglutide significantly improved perfusion recovery and capillary density in both nondiabetic and diabetic mice. Liraglutide also promoted, in a concentration-dependent manner, the proliferation, migration, and tube formation of normal glucose- and high glucose-treated human umbilical vein endothelial cells, as well as the phosphorylation of Akt, endothelial nitric oxide synthase, and extracellular signal-related kinases 1 and 2 both in vitro and in vivo. The liraglutide antagonist exendin (9-39) reversed the promoting effects of liraglutide on human umbilical vein endothelial cell functions. Furthermore, exendin (9-39), LY294002, and PD98059 blocked the liraglutide-induced activation of Akt/endothelial nitric oxide synthase and extracellular signal-related kinases 1 and 2 signaling pathways. Conclusions These studies identified a novel role of liraglutide in modulating ischemia-induced angiogenesis, possibly through effects on endothelial cell function and activation of Akt/endothelial nitric oxide synthase and extracellular signal-related kinases 1 and 2 signaling, and suggested the glucagon-like peptide-1 receptor may be an important therapeutic target in diabetic hind-limb ischemia.

Impact of Glucagon-like peptide 1 receptor agonists on peripheral arterial disease in people with diabetes mellitus: A narrative review

Peripheral arterial disease (PAD) is a common macrovascular complication of diabetes mellitus (DM). Glucagon-like peptide 1 (GLP-1) receptor agonists (GLP-1RAs) are among the latest class of antidiabetic medications that stimulate insulin synthesis and secretion and have been used for the management of type 2 DM. Apart from the effect on glycaemic control, GLP-1RAs also have a robust impact on weight reduction and have shown favorable effects on cardiovascular morbidity and mortality in cardiovascular outcome trials (CVOTs). The aim of this review was to examine the impact of GLP1-RAs on PAD among people with DM based on CVOTs, randomized controlled trials, observational studies as well as systematic reviews and meta-analyses. Data from retrospective studies and meta-analyses have shown superiority of these agents in comparison with other antidiabetic medications such as sodium-glucose cotransporter type 2 inhibitors and dipeptidyl peptidase-4 inhibitors in terms of PAD-related events. Nevertheless, data from CVOTs regarding the impact of GLP-1RAs on PAD are scarce and hence, safe conclusions regarding their effects cannot be drawn. Further prospective studies are needed to examine the impact of GLP-1RAs on PAD-related incidents including major adverse limb events, lower limb amputations and revascularization procedures.

Diabetic foot ulcer: Challenges and future

Diabetic foot ulcers (DFUs) have become one of the important causes of mortality and morbidity in patients with diabetes, and they are also a common cause of hospitalization, which places a heavy burden on patients and society. The prevention and treatment of DFUs requires multidisciplinary management. By controlling various risk factors, such as blood glucose levels, blood pressure, lipid levels and smoking cessation, local management of DFUs should be strengthened, such as debridement, dressing, revascularization, stem cell decompression and oxygen therapy. If necessary, systemic anti-infection treatment should be administered. We reviewed the progress in the clinical practice of treating DFUs in recent years, such as revascularization, wound repair, offloading, stem cell transplantation, and anti-infection treatment. We also summarized and prospectively analyzed some new technologies and measurements used in the treatment of DFUs and noted the future challenges and directions for the development of DFU treatments.

Astragalus Polysaccharides Promote Wound Healing in Diabetic Rats by Upregulating PETN and Inhibiting the mTOR Pathway

Objective. Presently, astragalus polysaccharide (APS) is being investigated for its therapeutic potential in various diseases; however, its underlying mechanism has not yet been clarified. This study was aimed at observing the effects of APS on wound healing in diabetic rats and at exploring its underlying mechanism. Methods. Streptozotocin was injected into the tail vein of SD rats to induce diabetic animal models, in which an incision on the back was made. Rats were treated with different dosages of APS to observe their wound healing. Additionally, RT-qPCR and Western blot assay were conducted to observe the expression levels of PTEN and mTOR pathway-associated factors. Results. Diabetic rats had a prolonged wound healing process, fewer blood vessels, and increased inflammatory response, in which decreased PTEN and elevated mTOR phosphorylation were also identified. APS effectively improved wound healing in a dose-dependent manner by inhibiting the release of inflammatory mediators and attenuating endothelial injuries. Suppression of PTEN could effectively increase the phosphorylation of mTOR and diminish the therapeutic functions of APS on wound healing in diabetic rats. Conclusion. This study highlighted that APS could promote wound healing in diabetic rats by upregulating PTEN and suppressing the mTOR pathway activation.

Intramuscular injection of sotagliflozin promotes neovascularization in diabetic mice through enhancing skeletal muscle cells paracrine function

Diabetes mellitus is associated with series of macrovascular and microvascular pathological changes that cause a wide range of complications. Diabetic patients are highly susceptible to hindlimb ischemia (HLI), which remains incurable. Evidence shows that skeletal muscle cells secrete a number of angiogenic factors to promote neovascularization and restore blood perfusion, this paracrine function is crucial for therapeutic angiogenesis in diabetic HLI. In this study we investigated whether sotagliflozin, an anti-hyperglycemia SGLT2 inhibitor, exerted therapeutic angiogenesis effects in diabetic HLI in vitro and in vivo. In C2C12 skeletal muscle cells, we showed that high glucose (HG, 25 mM) under hypoxia markedly inhibited cell viability, proliferation and migration potentials, which were dose-dependently reversed by pretreatment with sotagliflozin (5-20 μM). Sotagliflozin pretreatment enhanced expression levels of angiogenic factors HIF-1α, VEGF-A and PDGF-BB in HG-treated C2C12 cells under hypoxia as well as secreted amounts of VEGF-A and PDGF-BB in the medium; pretreatment with the HIF-1α inhibitor 2-methoxyestradiol (2-ME2, 10 μM) or HIF-1α knockdown abrogated sotagliflozin-induced increases in VEGF-A and PDGF-BB expression, as well as sotagliflozin-stimulated cell proliferation and migration potentials. Furthermore, the conditioned media from sotagliflozin-treated C2C12 cells in HG medium enhanced the migration and proliferation capabilities of vascular endothelial and smooth muscle cells, two types of cells necessary for forming functional blood vessels. In vivo study was conducted in diabetic mice subjected to excising the femoral artery of the left limb. After the surgery, sotagliflozin (10 mg/kg) was directly injected into gastrocnemius muscle of the left hindlimb once every 3 days for 3 weeks. We showed that intramuscular injection of sotagliflozin effectively promoted the formation of functional blood vessels, leading to significant recovery of blood perfusion in diabetic HLI mice. Together, our results highlight a new indication of SGLT2 inhibitor sotagliflozin as a potential therapeutic angiogenesis agent for diabetic HLI.

BAG3 Attenuates Ischemia-Induced Skeletal Muscle Necroptosis in Diabetic Experimental Peripheral Artery Disease

Peripheral artery disease (PAD) is characterized by impaired blood flow to the lower extremities, resulting in ischemic limb injuries. Individuals with diabetes and PAD typically have more severe ischemic limb injuries and limb amputations, but the mechanisms involved are poorly understood. Previously, we identified BAG3 as a gene within a mouse genetic locus termed limb salvage QTL1 on mouse chromosome 7 that determined the extent of limb necrosis following ischemic injury in C57Bl/6 mice. Whether BAG3 deficiency plays a role in the severe ischemic injury observed in diabetic PAD is not known. In vitro, we found simulated ischemia enhanced BAG3 expression in primary human skeletal muscle cells, whereas BAG3 knockdown increased necroptosis markers and decreased cell viability. In vivo, ischemic skeletal muscles from hind limbs of high-fat diet (HFD)-fed mice showed poor BAG3 expression compared to normal chow diet (NCD)-fed mice, and this was associated with increased limb amputations. BAG3 overexpression in ischemic skeletal muscles from hind limbs of HFD mice rescued limb amputation and improved autophagy, necroptosis, skeletal muscle function and regeneration. Therefore, BAG3 deficiency in ischemic skeletal muscles contributes to the severity of ischemic limb injury in diabetic PAD, likely through autophagy and necroptosis pathways.

Diabetic Foot Management: Education of Vascular Surgeons Remains a Priority

Diabetic foot ulcers remain difficult to heal, especially in the setting of peripheral arterial disease (PAD). Vascular surgeons are very important members of the multidisciplinary foot care team. To make the most of their potential, adequate education of vascular trainees on diabetic PAD remains a priority. This should include not only endovascular therapies but also open surgical approaches. Evaluation of trainees' skills, as well as of the educational program itself, is also desirable. Finally, simulation-based training may prove a useful educational tool.

Pro-angiogenic New Chloro-Azaphilone Derivatives From the Hadal Trench-Derived Fungus Chaetomium globosum YP-106

Five new chloro-azaphilones, chaetofanixins A–E (1–5), and five known analogs (6–10) were isolated and identified from the hadal trench-derived fungus Chaetomium globosum YP-106. The structure of chaetofanixin E (5) is unique and interesting, bearing a highly rigid 6/6/5/3/5 penta-cyclic ring system, which is first encountered in natural products. The structures of these compounds, including absolute configurations, were determined based on the spectroscopic analysis, electronic circular dichroism (ECD) calculations, and analysis of biogenetic origins. Compounds 1–7 significantly promoted angiogenesis in a dose-dependent manner, and thus, these compounds might be used as promising molecules for the development of natural cardiovascular disease agents.

Australian guideline on diagnosis and management of peripheral artery disease: part of the 2021 Australian evidence-based guidelines for diabetes-related foot disease

Background

Peripheral artery disease (PAD) is implicated in up to 50% of diabetes-related foot ulcers (DFU) and significantly contributes to morbidity and mortality in this population. An evidence-based guideline that is relevant to the national context including consideration of the unique geographical and health care system differences between Australia and other countries, and delivery of culturally safe care to First Nations people, is urgently required to improve outcomes for patients with PAD and DFU in Australia. We aimed to identify and adapt current international guidelines for diagnosis and management of patients with PAD and DFU to develop an updated Australian guideline.

Methods

Using a panel of national content experts and the National Health and Medical Research Council procedures, the 2019 International Working Group on the Diabetic Foot (IWGDF) guidelines were adapted to the Australian context. The guideline adaptation frameworks ADAPTE and Grading of Recommendations Assessment, Development and Evaluation (GRADE) were applied to the IWGDF guideline for PAD by the expert panel. Recommendations were then adopted, adapted or excluded, and specific considerations for implementation, population subgroups, monitoring and future research in Australia were developed with accompanying clinical pathways provided to support guideline implementation.

Results

Of the 17 recommendations from the IWGDF Guideline on diagnosis, prognosis and management of PAD in patients with diabetes with and without foot ulcers, 16 were adopted for the Australian guideline and one recommendation was adapted due to the original recommendation lacking feasibility in the Australian context. In Australia we recommend all people with diabetes and DFU undergo clinical assessment for PAD with accompanying bedside testing. Further vascular imaging and possible need for revascularisation should be considered for all patients with non-healing DFU irrespective of bedside results. All centres treating DFU should have expertise in, and/or rapid access to facilities necessary to diagnose and treat PAD, and should provide multidisciplinary care post-operatively, including implementation of intensive cardiovascular risk management.

Conclusions

A guideline containing 17 recommendations for the diagnosis and management of PAD for Australian patients with DFU was developed with accompanying clinical pathways. As part of the adaptation of the IWGDF guideline to the Australian context, recommendations are supported by considerations for implementation, monitoring, and future research priorities, and in relation to specific subgroups including Aboriginal and Torres Strait Islander people, and geographically remote people. This manuscript has been published online in full with the authorisation of Diabetes Feet Australia and can be found on the Diabetes Feet Australia website: https://www.diabetesfeetaustralia.org/new-guidelines/.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13047-022-00550-7.

Therapeutic angiogenesis-based strategy for peripheral artery disease

Peripheral artery disease (PAD) poses a great challenge to society, with a growing prevalence in the upcoming years. Patients in the severe stages of PAD are prone to amputation and death, leading to poor quality of life and a great socioeconomic burden. Furthermore, PAD is one of the major complications of diabetic patients, who have higher risk to develop critical limb ischemia, the most severe manifestation of PAD, and thus have a poor prognosis. Hence, there is an urgent need to develop an effective therapeutic strategy to treat this disease. Therapeutic angiogenesis has raised concerns for more than two decades as a potential strategy for treating PAD, especially in patients without option for surgery-based therapies. Since the discovery of gene-based therapy for therapeutic angiogenesis, several approaches have been developed, including cell-, protein-, and small molecule drug-based therapeutic strategies, some of which have progressed into the clinical trial phase. Despite its promising potential, efforts are still needed to improve the efficacy of this strategy, reduce its cost, and promote its worldwide application. In this review, we highlight the current progress of therapeutic angiogenesis and the issues that need to be overcome prior to its clinical application.

Estrogen-related receptor alpha is an AMPK-regulated factor that promotes ischemic muscle revascularization and recovery in diet-induced obese mice

Obesity and type II diabetes are leading causes of peripheral arterial disease (PAD), which is characterized by vascular insufficiency and ischemic damage in the limb skeletal muscle. Glycemic control is not sufficient to prevent progression of PAD, and molecular targets that can promote muscle neo-angiogenesis in obesity and diabetes remain poorly defined. Here, we have investigated whether nuclear receptor estrogen-related receptor alpha (ERRα) can promote ischemic revascularization in the skeletal muscles of diet-induced obese (DIO) mice. Using muscle-specific ERRα transgenic mice, we found that ERRα overexpression promotes revascularization, marked by increased capillary staining and muscle perfusion in DIO mice after hindlimb ischemic injury. Furthermore, ERRα facilitates repair and restoration of skeletal muscle myofiber size after limb ischemia in DIO mice. The ameliorative effects of ERRα overexpression did not involve the prevention of weight gain, hyperglycemia or glucose/insulin intolerance, suggesting a direct role for ERRα in promoting angiogenesis. Interestingly, levels of endogenous ERRα protein are suppressed in the skeletal muscles of DIO mice compared to lean controls, coinciding with the suppression of angiogenic gene expression, and reduced AMPK signaling in the DIO skeletal muscles. Upon further investigating the link between AMPK and ERRα, we found that AMPK activation increases the expression and recruitment of ERRα protein to specific angiogenic gene promoters in muscle cells. Further, the induction of angiogenic factors by AMPK activators in muscle cells is blocked by repressing ERRα. In summary, our results identify an AMPK/ERRα-dependent angiogenic gene program in the skeletal muscle, which is repressed by DIO, and demonstrate that forced ERRα activation can promote ischemic revascularization and muscle recovery in obesity.

Responsiveness and Inter-Rater Reliability of the Pulse Volume Recording Upstroke Ratio (PVRr)

The objective of this study was to evaluate a measure of the responsiveness and reliability of the pulse volume recording upstroke ratio (PVRr). A database of 389 subjects undergoing lower extremity revascularization was analyzed. Subjects were included in the analysis if they had undergone pedal radiographs, had PVRs performed pre- and postlower extremity revascularization, and had regular pulsatile digital waveforms with a pressure recording on both PVRs. The responsiveness of the PVRr was assessed by means of the postoperative percent change in comparison to the digital pressures. A statistically significant negative correlation was observed (Pearson -0.421; p = .007) indicating that as digital pressures increased, the PVRr decreased. Further, measurement of the reliability of the PVRr was performed on a selection of 10 recordings by 2 residents and 3 board-certified surgeons. The observed intraclass correlation coefficient of measurements was 0.960. Results of this investigation provide evidence in support of the responsiveness and inter-rater reliability in the calculation of the pulse volume recording upstroke ratio.

The current status of low-density lipoprotein cholesterol for primary prevention of coronary artery disease in late-stage elderly persons with type 2 diabetes mellitus: A retrospective, single-center study

Aims/Introduction

The importance of low‐density lipoprotein cholesterol (LDL‐C) in the primary prevention of cardiovascular disease has recently been reported in the population aged ≥75 years with hypercholesterolemia. Therefore, the current status of LDL‐C management for primary prevention of coronary artery disease in patients aged ≥75 years with type 2 diabetes mellitus was investigated.

Materials and Methods

A total of 124 patients aged ≥75 years who had type 2 diabetes mellitus, but no coronary artery disease, were investigated. The patients' background characteristics, LDL‐C, glycemic status, ankle‐brachial index and cardio‐ankle vascular index were compared between patients taking and not taking LDL‐C‐lowering agents, such as hydroxymethylglutaryl‐CoA reductase inhibitors (statins) and ezetimibe. The details of the antihyperlipidemic and antidiabetic agents used in the present study were also examined.

Results

LDL‐C was significantly lower in patients taking LDL‐C‐lowering agents (LDLCLT[+]) than in patients not taking them (LDLCLT[−]), although LDL‐C was maintained <120 mg/dL in both groups (93.0 mg/dL vs 102.1 mg/dL). Approximately half of the cases in the LDLCLT(+) group received moderate‐intensity statins, with pitavastatin being the most prescribed statin. Glycated hemoglobin was significantly lower in the LDLCLT(+) group than in the LDLCLT(−) group (6.9% vs 7.3%). Sodium‐glucose transporter 2 inhibitors were more frequently used in the LDLCLT(+) group than in the LDLCLT(−) group. The ankle‐brachial index/cardio‐ankle vascular index did not differ between the groups.

Conclusion

Low‐density lipoprotein cholesterol was properly managed for primary prevention of coronary artery disease in patients aged ≥75 years with type 2 diabetes mellitus regardless of the presence or absence of LDL‐C‐lowering agents.

Approximation of the Ankle-Brachial Index in the Setting of Medial Arterial Calcific Sclerosis

The presence of medial arterial calcific sclerosis is known to cause inaccuracy in the interpretation of noninvasive vascular testing. This substantially limits the utility of an important baseline diagnostic test for peripheral arterial disease. Therefore, the objective of this investigation was to derive a method to effectively factor out calcification in the interpretation of the ankle and digital brachial indices. The noninvasive vascular testing results of 160 subjects were stratified into the absence of calcification, mild calcification, moderate calcification, and severe calcification based on plain film radiographic findings of the infrageniculate vessels. Measurements were then performed of the pulse volume recording (PVR) waveforms at brachial, ankle and digital anatomic levels to include PVR wavelength and PVR upstroke length, with a calculation of the ratio of PVR upstroke length to PVR wavelength. These measurements were compared between groups and then correlated to the ankle and digital brachial indices. A significant difference was observed in the PVR upstroke ratio between the 3 anatomic levels (0.1818 vs 0.2622 vs 0.3191; p < .001), but not between the 4 calcification groups (0.2457 vs 0.2363 vs 0.2694 vs 0.2631; p = .242). A significant negative correlation was observed between the PVR upstroke ratio and the ankle brachial index (ABI) (Pearson -0.454; p = .002) with linear regression indicating the relationship is defined by the formula: Effective ankle brachial index = 1.17 - (1.33 × PVR upstroke ratio at ankle level). A significant negative correlation was also observed between the PVR upstroke ratio and the digital brachial index (Pearson -0.553; p < .001) with linear regression indicating the relationship is defined by the formula: Effective toe brachial index = 1.04 - (1.61 × PVR upstroke ratio at digital level). The results of this investigation demonstrate the feasibility of, and provide equations to approximate, the effective ankle brachial and toe brachial indices in the setting of medial arterial calcification.

[Physical and psychological long-term consequences of diabetes mellitus]

Trotz Verbesserungen in der Therapie des Diabetes und besseren Versorgungbedingungen weisen die Betroffenen aktuell im Vergleich zur Allgemeinbevölkerung noch immer ein deutlich erhöhtes Risiko für physische wie psychische Folgeerkrankungen sowie eine reduzierte Lebensqualität auf. Etwa 21 % aller Todesfälle sind in Deutschland auf Diabetes und seine Folgeerkrankungen zurückzuführen, das Mortalitätsrisiko ist für Menschen mit Diabetes um mehr als das 1,5-Fache gegenüber Menschen ohne Diabetes erhöht. In dieser Übersicht werden die Verbreitung und die Risikofaktoren für die häufigsten körperlichen und psychischen Folgen des Diabetes beschrieben sowie deren Einflüsse auf die Lebensqualität der Patienten. Zusammenhänge zwischen den Folgeerkrankungen und einer erhöhten Mortalität werden aufgezeigt.

In großen Interventionsstudien konnte die Bedeutung einer guten Glukoseeinstellung – vor allem zu Beginn der Erkrankung – in Hinblick auf eine Senkung der Mortalitätsrate gezeigt werden, weitere wichtige Einflussfaktoren sind z. B. Blutdruck, Blutfette und Rauchen. Weltweite Studienergebnisse deuten auf einen stabilen Trend hinsichtlich einer verbesserten Lebenserwartung von Menschen mit Diabetes in den letzten Jahren hin. Zukünftig könnte der positive Trend durch bessere Versorgungsstrukturen und neue Technologien sowie digitale Anwendungen in der Forschung und Therapie fortgesetzt werden. Mithilfe der Präzisionsmedizin könnten individuelle Risikofaktoren und protektive Faktoren erkannt werden, um der Entstehung von Folgekomplikationen noch besser vorzubeugen.

Predictive Value of Contrast-Enhanced Ultrasound in Chemical Lumbar Sympathectomy for End-Stage Arteriosclerosis Obliterans of the Lower Extremities

Introduction

The therapeutic effect of chemical lumbar sympathectomy (CLS) on ischemic diseases of the lower limbs varies greatly among individuals. The time to peak (TTP) response in contrast-enhanced ultrasound (CEUS) can reflect the perfusion disorder of the calf skeletal muscle and the collateral circulation. In this study we evaluated the predictive value of CEUS in patients treated with CLS for end-stage atherosclerotic occlusive disease of the lower extremity (ASO-LE).

Methods

This was a prospective study that included patients with end-stage ASO-LE and moderate to severe pain who had undergone a CEUS examination and CLS procedure and who were observed for 12 months after surgery. The patients’ characteristics and prognostic factors, including lower limb pain score, skin temperature, walking distance, and ulcer and gangrene healing, were recorded.

Results

Fifty-eight patients with a mean age of 66.24 (range 58–78) years were included in the study, of whom 42 (71.41%) were men. Following the CLS procedure, the numerical rating scale (NRS)-measured pain decreased significantly, and the skin temperature of the affected limb increased significantly (P < 0.05). The satisfaction rate of lower limb pain relief 1 year after operation was 53.45%. Correlation analysis showed that preoperative TTP response was correlated with the NRS score and skin temperature of the affected limb at 6 months and 12 months post surgery (P < 0.05). The binary logistic regression analysis indicated that a longer preoperative TTP response was associated with a higher risk of poor pain relief after CLS (odds ratio 1.126, 95% confidence interval 1.058–1.205). The receiver operating characteristic curve showed that preoperative TTP response had a certain predictive value on CLS treatment effect, with a sensitivity and specificity of 81.5% and 83.9%, respectively. When the preoperative TTP response was > 77.5, the risk of poor response after CLS increased.

Conclusions

Preoperative TTP response was able to predict the therapeutic effect of CLS to a certain extent, and thus may aid physicians in determining the choice of CLS treatment for patients with ASO-LE.

Trial Registration

Chinese Clinical Trial Registry: ChicTR1900028424 (principal investigator: Yue Wu; date of registration: 21 December 2019).

Supplementary Information

The online version contains supplementary material available at 10.1007/s40122-021-00347-9.

What is the Lived Experience of the ‘Three Great Pathologies’ of Diabetic Foot Disease? An Interpretative Phenomenological Analysis of the Independent Thinking of Podiatrists in Diabetes Secondary Care

Researching the podiatrists’ lived experience of The Three Great Pathologies may help improve the quality of patient care. The aim of this research using an Interpretative Phenomenological Analysis approach is to report on insights relating to the Three Great Pathologies of diabetic foot disease – infection, ischaemia and amputation. To do this, data was collected from six New Zealand diabetes care Podiatrists. Three superordinate themes resulted with subordinate themes. They are compromised health status, podiatric challenges and best outcomes. The findings are firstly, patient education remains a priority; secondly, there is an unmet need for postgraduate podiatry education; and thirdly, early intervention is a key measure for reducing the influence of the Three Great Pathologies. This study demonstrates that focussing on a group of six specialist podiatrists contributes to new priorities of care for dealing with the Three Great Pathologies of diabetic foot disease.

Modulation of miR-29a and ADAM12 Reduces Post-Ischemic Skeletal Muscle Injury and Improves Perfusion Recovery and Skeletal Muscle Function in a Mouse Model of Type 2 Diabetes and Peripheral Artery Disease

Both Type 1 diabetes mellitus (DM1) and type 2 diabetes mellitus (DM2) are associated with an increased risk of limb amputation in peripheral arterial disease (PAD). How diabetes contributes to poor PAD outcomes is poorly understood but may occur through different mechanisms in DM1 and DM2. Previously, we identified a disintegrin and metalloproteinase gene 12 (ADAM12) as a key genetic modifier of post-ischemic perfusion recovery. In an experimental PAD, we showed that ADAM12 is regulated by miR-29a and this regulation is impaired in ischemic endothelial cells in DM1, contributing to poor perfusion recovery. Here we investigated whether miR-29a regulation of ADAM12 is altered in experimental PAD in the setting of DM2. We also explored whether modulation of miR-29a and ADAM12 expression can improve perfusion recovery and limb function in mice with DM2. Our result showed that in the ischemic limb of mice with DM2, miR-29a expression is poorly downregulated and ADAM12 upregulation is impaired. Inhibition of miR-29a and overexpression of ADAM12 improved perfusion recovery, reduced skeletal muscle injury, improved muscle function, and increased cleaved Tie 2 and AKT phosphorylation. Thus, inhibition of miR-29a and or augmentation of ADAM12 improves experimental PAD outcomes in DM2 likely through modulation of Tie 2 and AKT signalling.

Discovery of Salidroside-Derivated Glycoside Analogues as Novel Angiogenesis Agents to Treat Diabetic Hind Limb Ischemia

Therapeutic angiogenesis is a potential therapeutic strategy for hind limb ischemia (HLI); however, currently, there are no small-molecule drugs capable of inducing it at the clinical level. Activating the hypoxia-inducible factor-1 (HIF-1) pathway in skeletal muscle induces the secretion of angiogenic factors and thus is an attractive therapeutic angiogenesis strategy. Using salidroside, a natural glycosidic compound as a lead, we performed a structure-activity relationship (SAR) study for developing a more effective and druggable angiogenesis agent. We found a novel glycoside scaffold compound (C-30) with better efficacy than salidroside in enhancing the accumulation of the HIF-1α protein and stimulating the paracrine functions of skeletal muscle cells. This in turn significantly increased the angiogenic potential of vascular endothelial and smooth muscle cells and, subsequently, induced the formation of mature, functional blood vessels in diabetic and nondiabetic HLI mice. Together, this study offers a novel, promising small-molecule-based therapeutic strategy for treating HLI.

Urinary pteridines as a discriminator of atherosclerotic risk in patients with diabetes

Background and aims

We have recently proposed urinary pteridine level as a useful biomarker of oxidative stress in a general population. However, the significance of urinary pteridines in patients with diabetes is unknown.

Methods

The relationships of the level of urinary pteridine derivatives with d-dimer, ankle-brachial pressure index (ABI), and known cardiovascular risk factors were investigated in patients with type 2 diabetes.

Results

Urinary pteridine level showed significant positive correlations with urinary15-isoprostane F2t, female gender, history of smoking and d-dimer and significant inverse correlations with history of alcohol drinking, body mass index (BMI) and ABI. ABI was significantly lower and d-dimer was significantly higher in the highest tertile group of pteridines than in the lowest tertile group. The odds ratios of the highest vs. lowest tertiles for low ABI and high d-dimer were significantly higher than the reference level. The above relationships of urinary pteridines with ABI and d-dimer were not altered when age, gender, BMI, hemoglobin A1c and history of alcohol drinking were used as explanatory variables in multivariable analyses. History of smoking confounded the relation of pteridines with ABI but not that with d-dimer. However, in logistic regression analysis, the association between pteridines and ABI remained significant with adjustment for history of smoking.

Conclusion

Urinary pteridine level was associated with d-dimer and ABI, which reflect blood coagulability and arterial flow to the lower extremities, respectively, and is thus thought to be a useful discriminator of thromboatherosclerotic risk in patients with diabetes.

Association of Advanced Glycation End Products With Lower-Extremity Atherosclerotic Disease in Type 2 Diabetes Mellitus

Aims: Advanced glycation end products (AGEs) were reported to be correlated with the development of diabetes, as well as diabetic vascular complications. Therefore, this study aimed at investigating the association between AGEs and lower-extremity atherosclerotic disease (LEAD). Methods: A total of 1,013 type 2 diabetes patients were enrolled. LEAD was measured through color Doppler ultrasonography. The non-invasive skin autofluorescence method was performed for AGEs measurement. Considering that age plays an important role in both AGEs and LEAD, age-combined AGEs, i.e., AGE_age index (define as AGEs × age/100) was used for related analysis. Results: The overall prevalence of LEAD was 48.9% (495/1,013). Patients with LEAD showed a significantly higher AGE_age (p < 0.001), and the prevalence of LEAD increased with ascending AGE_age levels (p for trend < 0.001). Logistic regression analysis revealed that AGE_age was significantly positively associated with risk of LEAD, and the odds ratios of presence of LEAD across quartiles of AGE_age were 1.00, 1.72 [95% confidence interval (CI) = 1.14-2.61], 2.72 (95% CI = 1.76-4.22), 4.29 (95% CI = 2.69-6.85) for multivariable-adjusted model (both p for trend < 0.001), respectively. The results were similar among patients of different sexes, body mass index, and with or without diabetes family history. Further, AGE_age presented a better predictive value for LEAD than glycated hemoglobin A_1c (HbA_1c), with its sensitivity, specificity, and area under the curve of 75.5% (95% CI = 71.6-79.2%), 59.3% (95% CI = 54.9-63.6%), and 0.731 (0.703-0.758), respectively. Conclusion: AGE_age, the non-invasive measured skin AGEs combined with age, seems to be a more promising approach than HbA_1c in identifying patient at high risk of LEAD.

Foot Revascularization Avoids Major Amputation in Persons with Diabetes and Ischaemic Foot Ulcers

The study aims to evaluate the effectiveness of foot revascularization in persons with diabetic foot ulcers (DFUs) and below-the-ankle (BTA) arterial disease. Consecutive patients referred for a new active ischaemic DFU requiring lower limb revascularization were considered. Among those, only patients with a BTA arterial disease were included. Revascularization procedures were retrospectively analysed: in the case of successful foot revascularization (recanalization of pedal artery, or plantar arteries or both) or not, patients were respectively divided in two groups, successful foot perfusion (SFP) and failed foot perfusion (FFP). Healing, minor and major amputation at 12 months of follow-up were evaluated and compared. Eighty patients (80) were included. The mean age was 70.5 ± 10.9 years, 55 (68.7%) were male, 72 (90%) were affected by type 2 diabetes with a mean duration of 22.7 ± 11.3 years. Overall 45 (56.2%) patients healed, 47 (58.7%) had minor amputation and 13 (16.2%) major amputation. Outcomes for SFP and FFP were respectively: healing (89.3 vs. 9.1%, p < 0.0001), minor amputation (44.7 vs. 78.8%, p = 0.0001), major amputation (2.1 vs. 36.3%, p < 0.0001). Failed foot revascularization resulted an independent predictor of non-healing, minor amputation, and major amputation. Foot revascularization is mandatory to achieve healing and avoid major amputation in persons with ischaemic DFU and BTA arterial disease.

Three-dimensional remodeling of functional cerebrovascular architecture and gliovascular unit in leptin receptor-deficient mice

The cerebrovascular sequelae of diabetes render victims more susceptible to ischemic stroke, vascular cognitive impairment, and Alzheimer's disease. However, limited knowledge exists on the progressive changes in cerebrovascular structure and functional remodeling in type 2 diabetes. To ascertain the impact of diabetes on whole-brain cerebrovascular perfusion, leptin-receptor-deficient mice were transcardially injected with tomato-lectin before sacrifice. The whole brain was clarified by the Fast free-of-acrylamide clearing tissue technique. Functional vascular anatomy of the cerebrum was visualized by light-sheet microscopy, followed by analysis in Imaris software. We observed enhanced neovascularization in adult db/db mice, characterized by increased branch level and loop structures. Microvascular hypoperfusion was initially detected in juvenile db/db mice, suggesting early onset of insufficient microcirculation. Furthermore, gliovascular unit remodeling was verified by loss of pericytes and overactivation of microglia and astrocytes in adult diabetic mice. However, the integrity of the blood-brain barrier (BBB) was fundamentally preserved, as shown by a lack of extravasation of IgG into the brain parenchyma. In summary, we, for the first time, reveal that functional cerebrovascular remodeling occurs as early as four weeks in db/db mice and the deficit in gliovascular coupling may play a role in cerebral hypoperfusion before BBB breakdown in 16-week-old db/db mice.

Effect of revascularisation on lower extremity muscle function in combined type 2 diabetes and critical limb threatening ischemia

BACKGROUND

Critical limb-threatening ischemia (CLTI) and type 2 diabetes (T2D) frequently co-exist and often with less favourable outcome after revascularisation. The objective was to evaluate the effects of revascularisation on muscle function, perfusion and mitochondrial respiration in patients with combined CLTI and T2D.

METHODS

A prospective translational observational study. Two groups of patients facing unilateral peripheral revascularisation was included: Patients suffering from combined disease with CLTI+T2D (n= 14) and patients suffering from CLTI (n= 15). During pedal exercise testing, calf muscle perfusion was monitored with near-infrared spectroscopy (NIRS) and leg arterial volume flow in the common femoral artery with duplex ultrasound. Calf muscle biopsy and subsequent assessment of mitochondrial respiratory capacity on isolated muscle fibres was performed. Tests was performed before and six weeks after revascularisation.

RESULTS

After revascularisation, patients CLTI+T2D improved in muscle force from 8.48 kg (CI: 7.49-9.46) to 13.11 kg (CI: 11.58-14.63), (P<.001). Conversely, muscle force in patients suffering from nondiabetic CLTI decreased from 10.03 kg (CI: 9.1-10.96) to 9.73 kg (CI: 8.77- 10.69), (P=0.042). Muscle oxygenation during exercise improved more in the CLTI+T2D group 6.36 AUC (Area Under Curve), ((μM/kg)s) (CI: 5.71-7.01) compared to 2.11 ((μM/kg)s) (CI:1.38-2.83) in the CLTI group (P=.002). No improvement or difference between groups regarding mitochondrial function was detected.

CONCLUSIONS

Patients with combined CLTI+T2D, had an unsuspected better effect of revascularisation compared to patients with non-diabetic CLTI, in terms of increased muscle force (MVC) and improved muscle perfusion. Further studies are needed to elucidate the apparent interaction of the CLTI and T2D syndromes.

Estrogen-related receptor α is involved in angiogenesis and skeletal muscle revascularization in hindlimb ischemia

Skeletal muscle ischemia is a major consequence of peripheral arterial disease (PAD) or critical limb ischemia (CLI). Although therapeutic options for resolving muscle ischemia in PAD/CLI are limited, the issue is compounded by poor understanding of the mechanisms driving muscle vascularization. We found that nuclear receptor estrogen-related receptor alpha (ERRα) expression is induced in murine skeletal muscle by hindlimb ischemia (HLI), and in cultured myotubes by hypoxia, suggesting a potential role for ERRα in ischemic response. To test this, we generated skeletal muscle-specific ERRα transgenic (TG) mice. In these mice, ERRα drives myofiber type switch from glycolytic type IIB to oxidative type IIA/IIX myofibers, which are typically associated with more vascular supply in muscle. Indeed, RNA sequencing and functional enrichment analysis of TG muscle revealed that "paracrine angiogenesis" is the top-ranked transcriptional program activated by ERRα in the skeletal muscle. Immunohistochemistry and angiography showed that ERRα overexpression increases baseline capillarity, arterioles and non-leaky blood vessel formation in the skeletal muscles. Moreover, ERRα overexpression facilitates ischemic neo-angiogenesis and perfusion recovery in hindlimb musculature of mice subjected to HLI. Therefore, ERRα is a hypoxia inducible nuclear receptor that is involved in skeletal muscle angiogenesis and could be potentially targeted for treating PAD/CLI.

Nano encapsulated novel compound SA-10 with therapeutic activity in both acute and chronic murine hindlimb ischemia models

The production dysregulation of reactive oxygen species (ROS) and nitric oxide (NO) in ischemic tissues results in endothelial dysfunction, hyperinflammation and poor blood circulation. Here, we report a hybrid molecule, SA-10 with both NO donating and ROS scavenging abilities that demonstrated potent cytoprotection and tube formation activity in endothelial cells under H₂O₂-induced oxidative stress. SA-10 loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (SA-10 NPs) were delivered intramuscularly (IM) to two murine hindlimb ischemia models. In the acute mode ischemia/reperfusion (I/R), the muscle damage, hyperinflammation, and lung edema were significantly reduced 3 days post-dose while in the chronic ischemia model, significant improvement of blood perfusion and physical endurance was observed over 30 days (P < 0.05). Elderly patients with acute and chronic limb ischemia have limited options for surgical or endovascular interventions, so we anticipate that a product like SA-10 NPs has potential as one of the therapeutic alternatives to surgery.

Main Factors Predicting Nonresponders to Autologous Cell Therapy for Critical Limb Ischemia in Patients With Diabetic Foot

Autologous cell therapy (ACT) is a new treatment for patients with no-option critical limb ischemia (NO-CLI). We evaluated the factors involved in the nonresponse to ACT in patients with CLI and diabetic foot. Diabetic patients (n = 72) with NO-CLI treated using ACT in our foot clinic over a period of 8 years were divided into responders (n = 57) and nonresponders (n = 15). Nonresponder was defined as an insufficient increase in transcutaneous oxygen pressure by <5 mm Hg, 3 months after ACT. Patient demographics, diabetes duration and treatment, and comorbidities as well as a cellular response to ACT, limb-related factors, and the presence of inherited thrombotic disorders were compared between the 2 groups. The main independent predictors for an impaired response to ACT were heterozygote Leiden mutation (OR 10.5; 95% CI, 1.72-4) and homozygote methylenetetrahydrofolate reductase (MTHFR 677) mutation (OR 3.36; 95% CI, 1.0-14.3) in stepwise logistic regression. Univariate analysis showed that lower mean protein C levels (P = .041) were present in nonresponders compared with responders. In conclusion, the significant predictors of an impaired response to ACT in diabetic patients with NO-CLI were inherited thrombotic disorders.

The risk of micro and macrovascular disease in Egyptian patients with diabetes and peripheral arterial disease

Aim: The aim of this study was to assess the prevalence of micro- and macrovascular disease in Egyptian patients with diabetes mellitus (DM) and peripheral arterial disease (PAD). Methods: The study included 161 Egyptian patients with DM and PAD (91.3% had type 2 DM and 67.1% were females). Mean diabetes duration was 14.2 ± 5.2 years. Full history, clinical and fundus examination as well as laboratory investigations were done. PAD was diagnosed through assessment of ankle/brachial index (ABI) by Doppler ultrasonography. Results: ABI was <0.9 in 33.5% and >1.3 in 66.5% of patients. A significant positive correlation was found between abnormal ABI and diabetes duration, ischemic heart disease (IHD), diabetic retinopathy and neuropathy, foot ulcers, elevated blood pressure (BP), creatinine, urine albumin/creatinine ratio (ACR) and triglycerides and a significant negative correlation with HDL. Multivariate regression analysis revealed that the independent predictors for PAD in patients with ABI< 0.9 were neuropathy, creatinine, triglyceride, LDL, urine ACR and low HDL, and in patients with ABI >1.3 were IHD, neuropathy, elevated diastolic BP and triglyceride. Conclusion: The risk of micro- and macrovascular disease is high in Egyptian patients with diabetes and PAD. Early diagnosis and good control of risk factors could reduce PAD progression.

Strategies to Overcome the Barrier of Ischemic Microenvironment in Cell Therapy of Cardiovascular Disease

The transplantation of various immune cell types are promising approaches for the treatment of ischemic cardiovascular disease including myocardial infarction (MI) and peripheral arterial disease (PAD). Major limitation of these so-called Advanced Therapy Medicinal Products (ATMPs) is the ischemic microenvironment affecting cell homeostasis and limiting the demanded effect of the transplanted cell products. Accordingly, different clinical and experimental strategies have been evolved to overcome these obstacles. Here, we give a short review of the different experimental and clinical strategies to solve these issues due to ischemic cardiovascular disease.

Apolipoprotein E Gene Polymorphism, Glycated Hemoglobin, and Peripheral Arterial Disease Risk in Chinese Type 2 Diabetic Patients

Background

The apolipoprotein E (ApoE) gene polymorphism has been found to influence plasma lipid concentration, and its correlation with peripheral arterial disease (PAD) has been investigated. However, it is unclear whether ApoE is associated with PAD in Chinese type 2 diabetes mellitus (T2DM) patients. Therefore, our study is aimed at investigating the relationship between the ApoE gene polymorphism and PAD in Chinese T2DM patients.

Methods

A total of 192 T2DM patients were divided into two groups: T2DM and T2DM with PAD. The clinical and biochemical parameters were obtained. Polymerase chain reaction was used to identify the genotypes of ApoE. The multivariable logistic regression analysis was used to identify the possible risk factor for PAD.

Results

There were no significant differences in the genotype and allele frequencies of ApoE between the T2DM and T2DM with PAD groups. However, the T2DM with PAD group tended to have more ε4/ε4/

Conclusions

These results demonstrated that there was no evidence of a relationship between ApoE and PAD.

Growth Factor Deregulation and Emerging Role of Phosphatases in Diabetic Peripheral Artery Disease

Peripheral artery disease is caused by atherosclerosis of lower extremity arteries leading to the loss of blood perfusion and subsequent critical ischemia. The presence of diabetes mellitus is an important risk factor that greatly increases the incidence, the progression and the severity of the disease. In addition to accelerated disease progression, diabetic patients are also more susceptible to develop serious impairment of their walking abilities through an increased risk of lower limb amputation. Hyperglycemia is known to alter the physiological development of collateral arteries in response to ischemia. Deregulation in the production of several critical pro-angiogenic factors has been reported in diabetes along with vascular cell unresponsiveness in initiating angiogenic processes. Among the multiple molecular mechanisms involved in the angiogenic response, protein tyrosine phosphatases are potent regulators by dephosphorylating pro-angiogenic tyrosine kinase receptors. However, evidence has indicated that diabetes-induced deregulation of phosphatases contributes to the progression of several micro and macrovascular complications. This review provides an overview of growth factor alterations in the context of diabetes and peripheral artery disease, as well as a description of the role of phosphatases in the regulation of angiogenic pathways followed by an analysis of the effects of hyperglycemia on the modulation of protein tyrosine phosphatase expression and activity. Knowledge of the role of phosphatases in diabetic peripheral artery disease will help the development of future therapeutics to locally regulate phosphatases and improve angiogenesis.

Cirrhosis and insulin resistance: current knowledge, pathophysiological mechanisms, complications and potential treatments

End-stage chronic liver diseases are often associated with insulin resistance (IR) and diabetes mellitus (DM). Indeed, to quantify insulin sensitivity the euglycemic clamp technique was utilized, allowing the following to be stated: in small groups of patients, an IR in almost all cirrhotic patients can be observed, compared with a control group. Additionally, it has been demonstrated that IR in cirrhosis is linked to a decreased peripheral (muscle) glucose uptake rather than an increased liver glucose production. The homoeostasis model of IR (HOMA-IR) technique, devised only later, was then exploited to assess this same phenomenon in a larger sample population. The research established that even in patients with preserved liver function, cirrhosis is associated with significant alterations in glucose homoeostasis levels. The purpose of the present paper is to present the current research around the affiliation of cirrhosis and IR, discuss potential mechanisms explaining the association between cirrhosis and IR (i.e. endocrine perturbation, liver inflammation, altered muscle mass and composition, altered gut microbiota and permeability), complications that can arise as well as treatment options, through a critical review of the literature surrounding this subject. This research will also be investigating the beneficial impact, if there is any, of identifying and curing IR in patients with cirrhosis.

Effects of Postoperative Percutaneous Coronary Intervention, Pharmacologic Treatment, and Predisposing Factors on Clinical Outcomes in Patients With and Without Type 2 Diabetes Along With Critical Limb Ischemia

PURPOSE

Critical limb ischemia (CLI) has been identified as being connected to rates of cardiovascular mortality and lower extremity amputation (LEA). This prospective study investigated the effects of percutaneous coronary intervention (PCI), pharmacologic treatment, and predisposing factors on clinical outcomes in patients with and without type 2 diabetes mellitus (DM) along with CLI after endovascular intervention.

METHODS

249 consecutive patients with CLI (Fontaine stages III-IV) received pharmacologic treatment after successful endovascular intervention. Their primary patency rates of infrapopliteal lesions and cardiovascular and amputation events during a 36-month follow-up period were assessed.

FINDINGS

Patients with DM were more likely to be younger (P = 0.026); 50% (n = 63), 42.9% (n = 54), 52.4% (n = 66), and 77% (n = 97) of DM patients had arterial calcification, end-stage renal disease, diabetic neuropathy, and Fontaine stage IV (P < 0.001, P < 0.001, P < 0.001, and P = 0.019, respectively). The primary patency rates were 61%, 48.8%, and 42.3% at 12, 24, and 36 months, in the patients without DM (P = 0.034, P = 0.013, and P = 0.005). Patients with DM had higher risks of 36-month coronary artery disease, cerebrovascular accident, mortality, and LEA (P = 0.005, P = 0.042, P = 0.042, and P < 0.001). Patients with CLI receiving long-term cilostazol treatment had a better primary patency and amputation-free survival, and a lower risk of mortality at 36 months (P < 0.001, P < 0.001, and P = 0.001). Statin use was associated with 36-month amputation-free survival but not with primary patency (P = 0.032 and P = 0.088). Subgroup multivariate Cox analyses showed that primary patency was independently associated with long-term cilostazol treatment, PCI in the first postoperative year, and direct revascularization in the DM group, whereas in the control group, long-term cilostazol treatment was the main independent factor. The risk of amputation was independently associated with a high high-sensitivity chronic reactive protein level, diabetic neuropathy, sole use of an oral hypoglycemic agent, and lack of supervised exercise.

IMPLICATIONS

Long-term cilostazol treatment, aggressive management of dyslipidemia, and meticulous assessment and prevention of postoperative unstable coronary artery disease should be considered in CLI patients with and without DM to maximize clinical outcomes. PCI in the first postoperative year may be a predisposing factor for patency failure in patients with CLI, especially those with DM. A large-scale prospective randomized trial should be conducted to confirm these findings (TVGH IRB No. 2013-08-020B).

Chronic Lower Extremity Ischemia and Its Association with the Frailty Syndrome in Patients with Diabetes

Diabetes mellitus is an important risk factor for the development of cardiovascular diseases. Peripheral arterial disease affecting lower limb arteries is one of the clinical manifestations of atherosclerosis. The frailty syndrome (Frailty) is a problem associated with diminution of physiological reserves. The ankle-brachial index is a commonly used tool for diagnosing peripheral arterial disease (PAD). The usefulness of the ankle-brachial index (ABI) is limited in people with diabetes because of calcification of the middle layer of arteries. In this population, toe-brachial index should be measured. Frailty may be associated with worse prognosis for patients undergoing revascularization. Amputation may be an important factor leading to the development of Frailty. The risk of amputation and the prognosis after revascularization may be modified by some medications and blood glucose levels. The purpose of this paper is to review the literature about the association between PAD, especially in patients living with diabetes and Frailty.

Vitamin D Deficiency May Not Be an Independent Risk Factor for Peripheral Arterial Disease in Middle-Aged and Elderly Patients with Type 2 Diabetes in China

Background

Vitamin D deficiency can lead to the increased severity and prevalence of metabolic disorders. However, the relationship between levels of 25-hydroxyvitamin D (25(OH)D) and peripheral arterial disease (PAD) is controversial. Therefore, the purpose of our study was to explore the relationship between 25(OH)D levels and PAD in middle-aged and elderly type 2 diabetes mellitus (T2DM) patients in China.

Methods

In this study, a total of 183 patients with T2DM were enrolled and categorized into groups with or without PAD. Clinical and biochemical parameters were assessed, and a Pearson analysis was used to identify a possible association between levels of 25(OH)D and glycated hemoglobin (HbA1c). Some biochemical parameters were also assessed in the T2DM patients with PAD according to vitamin D status. Interactions were also explored among HbA1c control, 25(OH)D levels, and PAD. The possible risk factors for PAD were measured by multivariable logistic regression analyses.

Results

Firstly, the parameters including age, HbA1c, and disease duration between T2DM and T2DM+PAD groups showed significantly different. In addition, the frequency of smoking in the group of T2DM patients was significantly less than that in the T2DM patients with the PAD group, while the frequency of well-controlled HbA1c in the patients with T2DM was significantly higher. There is a trend that the levels of 25(OH)D and HbA1c are correlated, but no interactions among vitamin D deficiency, HbA1c control, and PAD were found. However, HbA1c significantly differed between groups with vitamin D deficiency and insufficiency in the T2DM patients with PAD. According to the multivariate logistic regression analyses, the PAD risk factors of T2DM patients were family history of diabetes, smoking, age, disease duration, HbA1c, and LDL.

Conclusions

The findings demonstrate that the deficiency of vitamin D level is not related to PAD, but HbA1c may be linked to the presence of PAD in middle-aged and elderly patients with T2DM in China.

Prevalence and predictors of peripheral arterial disease determined by ankle brachial index in diabetes population treated within primary care services in a non-urban area of lower northern Thailand

In diabetes patients, urban lifestyle has been concerned as one of the risk factors for peripheral arterial disease (PAD). The aims of this study were to find out the prevalence and associated risk factors of PAD in type 2 diabetes patients who live in a non-urban community area. A total of 885 participants with type 2 diabetes mellitus were enrolled from six primary care units in the health network centered at Naresuan University Hospital, Phitsanulok, between May and June 2018. Ankle-brachial index (ABI) was performed in all subjects using a vascular screening device. PAD was defined by an ABI value of 0.9 or lesser at least on one leg. The predictors of PAD were analyzed using multiple logistic regression. The prevalence of PAD was 7.2% among 884 evaluable patients. Diabetic neuropathy and a history of macrovascular complications were significant predictors of PAD.

Kanglexin accelerates diabetic wound healing by promoting angiogenesis via FGFR1/ERK signaling

Diabetic foot is one of the main causes of non-traumatic amputation. However, there is still lack of effective drugs to treat diabetic foot in clinical practice. Kanglexin (KLX) is a new anthraquinone compound with cardiovascular protective effects. Here we report that KLX accelerates diabetic wound healing by promoting angiogenesis via FGFR1/ERK signaling. Firstly, KM mice were injected (ip) with streptozocin to establish type 1 diabetic model. The full thickness wound with the diameter of 5 mm was prepared on the back of each mice. The wounds were treated with KLX once a day for 14 consecutive days. Results showed that KLX significantly accelerated the closure of diabetic wounds. Pathological studies of skin tissues around the wounds showed that KLX promoted the formation of granulation tissue and new blood vessels, increased collagen deposition and reduced inflammatory cell infiltration. Besides, KLX significantly alleviated advanced glycation end products (AGEs) - induced abnormal proliferation, migration and tubule formation of human umbilical vein endothelial cells (HUVECs), and up-regulated phospho-ERK1/2 both in the diabetic wound tissue and AGEs - treated HUVECs. Moreover, molecular docking results indicated that KLX had the potential to bind with FGF receptor 1 (FGFR1), and subsequent experiments confirmed that FGFR1 inhibitor PD173074 reversed the effect of KLX on promoting the phosphorylation of ERK1/2 and angiogenesis, suggesting that KLX promoted angiogenesis through FGFR1/ERK signaling. In conclusion, our study provides a new effective compound for treating diabetic wounds. More importantly, KLX has the potential to be developed as a topical drug to promote diabetic wound healing.