Nutritional interventions for treating foot ulcers in people with diabetes

Effect of composite biodegradable biomaterials on wound healing in diabetes

The repair of diabetic wounds has always been a job that doctors could not tackle quickly in plastic surgery. To solve this problem, it has become an important direction to use biocompatible biodegradable biomaterials as scaffolds or dressing loaded with a variety of active substances or cells, to construct a wound repair system integrating materials, cells, and growth factors. In terms of wound healing, composite biodegradable biomaterials show strong biocompatibility and the ability to promote wound healing. This review describes the multifaceted integration of biomaterials with drugs, stem cells, and active agents. In wounds, stem cells and their secreted exosomes regulate immune responses and inflammation. They promote angiogenesis, accelerate skin cell proliferation and re-epithelialization, and regulate collagen remodeling that inhibits scar hyperplasia. In the process of continuous combination with new materials, a series of materials that can be well matched with active ingredients such as cells or drugs are derived for precise delivery and controlled release of drugs. The ultimate goal of material development is clinical transformation. At present, the types of materials for clinical application are still relatively single, and the bottleneck is that the functions of emerging materials have not yet reached a stable and effective degree. The development of biomaterials that can be further translated into clinical practice will become the focus of research.

Nutritional supplementation on wound healing in diabetic foot: What is known and what is new?

Non-healing diabetic foot ulcers (DFU) are the most notable and striking complications of diabetes mellitus. More than 25% of nonhealing DFU can ultimately lead to amputation of the lower extremity within 6-18 mo after the first manifestation of the wound. Although wound healing is complex, nutritional status is crucial in soft tissue repair. Malnutrition is highly prevalent and overlooked in patients with diabetes and chronic wounds. Moreover, to date, we do not have clear recommendations or evidence about the use of nutritional supplements for improving wound healing in patients with DFU. In this article the authors briefly analyzed the current evidence on the use of nutritional supplements of proteins or amino acids, fatty acids, probiotics, vitamins, and trace elements in the wound healing process in patients with DFU.

Effects of Oral Nutritional Supplementation on Patients with Venous Ulcers: A Clinical Trial

Background: The dosage and safety of nutritional supplements for patients with venous ulcers are still not well established. Aim: To evaluate the effects of a high calorie, high protein, arginine-, zinc-, and vitamins A, C, and E-enriched nutritional supplement on the biochemical profile, dietary intake, anthropometry, muscle strength, and characteristics of lesions of patients with venous ulcers. Methods: A controlled before−after clinical trial with a four-week follow-up involved 27 patients with venous ulcers under outpatient treatment in Brazil. It was administered in two to three doses per day (200 mL each) of a high-calorie and high-protein supplement enriched with arginine, zinc, and vitamins A, C, and E. Patients were assessed for anthropometric parameters, dietary intake, biochemical tests, and healing conditions according to the Pressure Ulcer Scale for Healing (PUSH). Results: It was observed that an increase in energy and protein supply led to an adequate intake of immunonutrients (zinc and vitamins A, C, and E), increased body weight, increased body mass index, and stronger handgrip strength. The injury area and the score on the PUSH notably decreased after the intervention (p < 0.001). Conclusions: The administered supplement, at the tested dosage, improved the nutritional status and characteristics of lesions in patients with venous ulcers.

Dietary Risk Factors and Eating Behaviors in Peripheral Arterial Disease (PAD)

Dietary risk factors play a fundamental role in the prevention and progression of atherosclerosis and PAD (Peripheral Arterial Disease). The impact of nutrition, however, defined as the process of taking in food and using it for growth, metabolism and repair, remains undefined with regard to PAD. This article describes the interplay between nutrition and the development/progression of PAD. We reviewed 688 articles, including key articles, narrative and systematic reviews, meta-analyses and clinical studies. We analyzed the interaction between nutrition and PAD predictors, and subsequently created four descriptive tables to summarize the relationship between PAD, dietary risk factors and outcomes. We comprehensively reviewed the role of well-studied diets (Mediterranean, vegetarian/vegan, low-carbohydrate ketogenic and intermittent fasting diet) and prevalent eating behaviors (emotional and binge eating, night eating and sleeping disorders, anorexia, bulimia, skipping meals, home cooking and fast/ultra-processed food consumption) on the traditional risk factors of PAD. Moreover, we analyzed the interplay between PAD and nutritional status, nutrients, dietary patterns and eating habits. Dietary patterns and eating disorders affect the development and progression of PAD, as well as its disabling complications including major adverse cardiovascular events (MACE) and major adverse limb events (MALE). Nutrition and dietary risk factor modification are important targets to reduce the risk of PAD as well as the subsequent development of MACE and MALE.

Perceptions of Diet Quality, Advice, and Dietary Interventions in Individuals with Diabetes-Related Foot Ulceration; A Qualitative Research Study

BACKGROUND

Dietary intake is a recognised contributor to healing in diabetes-related foot ulceration (DFU). However, it is currently unknown how individuals with DFU perceive their diet, and what is deemed an acceptable dietary intervention. Therefore, the aims of this study were to explore perceptions of diet quality, previous dietary advice, and dietary interventions in individuals with DFU, and secondly to determine acceptable dietary interventions in individuals with DFU to assist with wound healing.

METHODS

A qualitative study using reflexive thematic analysis was undertaken. Individuals with active or recent history of DFU were recruited from a high-risk foot service. Semi-structured interviews were undertaken.

RESULTS

Nineteen participants were included with three themes identified: A complex relationship with food, perceptions of food, diet and dietitians, and self-management. Dietary misconceptions were common. Self-perceived diet quality varied, with most unaware of how diet could impact wound healing. Many expressed barriers relating to food agency (purchasing, preparing, and accessing food). Participants expressed a strong preference for personalised, face-to-face dietary advice and nutritional supplementation.

CONCLUSIONS

There is a need for personalised dietary re-education and assistance with food agency in this cohort to overcome commonly held misconceptions of diet and improve dietary intake to facilitate wound healing.

Impact of Serum Zinc Level and Oral Zinc Supplementation on Clinical Outcomes in Patients Undergoing Infrainguinal Bypass for Chronic Limb-Threatening Ischemia

BACKGROUND

Zinc (Zn) has been reported to play an important role in wound healing (WH). Nevertheless, the effect of Zn in chronic limb-threatening ischemia (CLTI) patients is unclear. This study investigated the effect of Zn on the clinical outcomes of CLTI patients undergoing bypass surgery.Methods and Results:This study reviewed 111 consecutive patients who underwent an infrainguinal bypass from 2012 to 2020. Patients with Zn deficiency (serum Zn level <60 μg/dL) received oral Zn supplementation and maintained a normal level until WH. This study aimed to explore: (1) the effect of Zn deficiency; and (2) Zn supplementation in Zn-deficient patients on the clinical outcomes of this cohort. Patients with Zn deficiency, Zn supplementation, and no Zn supplementation despite Zn deficiency accounted for 48, 21, and 42 patients, respectively. (1) Zn deficiency was associated with WH (HR, 0.47; 95% CI, 0.29-0.78: P=0.003), major adverse limb events (MALE) (HR, 2.53; 95% CI, 1.26-5.09: P=0.009), and major amputation or death (HR, 3.17; 95% CI, 1.51-6.63: P=0.002). (2) Zn supplementation was positively related to WH (HR, 2.30; 95% CI, 1.21-4.34: P=0.011). This result was confirmed using propensity score matching (HR, 2.24; 95% CI, 1.02-4.87: P=0.043).

CONCLUSIONS

The current study revealed that Zn level was associated with clinical outcomes in CLTI patients after bypass surgery. Oral Zn supplementation could improve WH in these patients.

RJX Improves Wound Healing in Diabetic Rats

BACKGROUND

We recently reported the clinical safety profile of RJX, a well-defined intravenous GMP-grade pharmaceutical formulation of anti-oxidant and anti-inflammatory vitamins as active ingredients, in a Phase 1 study in healthy volunteers (ClinicalTrials.gov Identifier: NCT03680105) (Uckun et al., Front. Pharmacol. 11, 594321. 10.3389/fphar.2020.594321). The primary objective of the present study was to examine the effects of GMP-grade RJX on wound and burn injury healing in diabetic rats.

METHODS

In the present study, a rat model of T2DM was used that employs HFD in combination with a single injection of STZ intraperitoneally (i.p) at a moderate dose level (45 mg/kg). Anesthetized diabetic rats underwent full-thickness skin excision on the back or were subjected to burn injury via a heated brass probe and then started on treatments with normal saline (NS = vehicle) or RJX administered via intraperitoneal injections for three weeks.

FINDINGS

Notably, diabetic rats treated with the 1.25 mL/kg or 2.5 mL/kg RJX (DM+RJX groups) rapidly healed their wounds as fast as non-diabetic control rats. Inflammatory cell infiltration in the dermis along with fibrin and cell debris on the epithelial layer persisted for up to 14 days in the DM+NS group but not in RJX-treated groups. The histopathological score of wound healing on days 7 and 14 was better in diabetic rats treated with RJX than diabetic rats treated with NS and comparable to the scores for non-diabetic healthy rats consistent with an accelerated healing process. The residual wound area of RJX-treated rats was significantly smaller than that of NS-treated diabetic rats at each evaluation time point (P<0.001). The accelerating effect of RJX on diabetic wound healing was dose-dependent. We obtained similar results in the burn injury model. Our results demonstrate that RJX - at a dose level >10-fold lower than its clinical maximum tolerated dose (MTD) - accelerates the healing of excision wounds as well burn injury in diabetic rats.

[Nutrition in the prevention and healing of chronic wounds. Importance in improving the diabetic foot]

Nutrition plays an essential role in chronic wound healing as extra nutrients are needed for tissue repair and to restore losses through wound exudate. Insufficient intake of energy, protein, antioxidants (vitamin C, A, and zinc) and vitamin D are common in patients with chronic wounds and have been linked to delayed wound healing and dehiscence. Other risk factors such as obesity, diabetes, advanced age, corticosteroid use, and dehydration can also reduce or impede the healing process, and nutritional screening is important to identify patients with malnutrition. Proteins, amino acids (arginine, glutamine and methionine), vitamins C and A, and zinc have been used as pharmacological nutrients in pressure ulcer healing; however, omega-3 fatty acids, although they appear to slow progression, do not show improved healing rates. In patients with diabetic foot, supplementation with vitamins D, C, A, and E, magnesium, zinc, omega-3 fatty acids, and probiotics reduces ulcer size and improves glycemic control, although they have not been associated with complete healing; however, supplementation with arginine, glutamine, and β-hydroxy-β-methylbutyrate does show wound healing, although further evidence is needed to confirm these results.

Associations between Nutrients and Foot Ulceration in Diabetes: A Systematic Review

We reviewed the literature to evaluate potential associations between vitamins, nutrients, nutritional status or nutritional interventions and presence or healing of foot ulceration in diabetes. Embase, Medline, PubMed, and the Cochrane Library were searched for studies published prior to September 2020. We assessed eligible studies for the association between nutritional status or interventions and foot ulcers. Fifteen studies met the inclusion criteria and were included in this review. Overall, there is a correlation between poor nutritional status and the presence of foot ulceration or a delay in healing. However, there is not enough data to reach conclusions about whether the relationships are causal or only association. Further research is required to test whether any forms of nutritional supplementation improve foot ulcer healing.