Mixture of Arginine, Glutamine, and β-hydroxy-β-methyl Butyrate Enhances the Healing of Ischemic Wounds in Rats

Impact of oral nutritional supplement composition on healing of different chronic wounds: A systematic review

Chronic wounds are characterized by prolonged non-healing, significantly affecting patients' quality of life. Oral formulas may enhance the wound healing process and contribute to cost reduction in care. This review aimed to evaluate the effects of oral nutritional supplementation on chronic wound healing and provide insights into formula characteristics. A comprehensive search across Cinahl, Embase, PubMed, and Web of Science databases yielded nine studies from the past decade involving 741 patients ages 52 to 81.7 across various care settings: hospitals, long-term care facilities, and home care. Primary wound types included pressure injuries (58%), diabetic foot ulcers (40%), and venous ulcers (2%). The intervention duration ranged from 2 to 16 wk, with sample sizes varying from 24 to 270 patients. Notably, four studies reported a reduction in wound area and an increased healing rate with a hypercaloric, hyperproteic formula enriched with zinc and vitamins A, C, and E. However, two studies found no significant differences compared with control groups. Two other studies investigated a combination of arginine, glutamine, and β-hydroxy-β-methylbutyrate; however, they did not yield significant results, and one study favored a hyperproteic formula instead of a hyperproteic formula with arginine. This review provides evidence supporting the potential of oral nutritional supplementation to enhance the healing process of chronic wounds. Based on our findings, a desirable formula should be characterized by a high calorie and protein content and the inclusion of antioxidant micronutrients, including, but not limited to, vitamins A, E, C, and zinc.

Long-term supplementation with a combination of beta-hydroxy-beta-methylbutyrate, arginine, and glutamine for pressure ulcer in sedentary older adults: a retrospective matched case-control study

BACKGROUND

Growing evidence suggests that beta-hydroxy-beta-methylbutyrate (HMB), arginine (Arg), and glutamine (Gln) positively affect wound recovery. This study investigated the effects of long-term administration of HMB/Arg/Gln on pressure ulcer (PU) healing in sedentary older adults admitted to geriatric and rehabilitation care facilities.

METHODS

This was a pilot retrospective case (standard of care and HMB/Arg/Gln)-control (standard of care alone) clinical study. Outcome measures were relative healing rates and Pressure Ulcer Scale for Healing (PUSH) scores (calculated after 4, 8, 12, 16, and 20 weeks) and time to healing.

RESULTS

The study subpopulation was comprised of 14 participants (four males, 28.6%) with the median age of 85.5 years (interquartile range [IQR], 82.0-90.2 years). The control subpopulation was comprised of 31 participants (18 males, 58.1%) with the median age of 84.0 years (IQR, 78.0-90.0 years). At the beginning of follow-up, there were no statistically significant demographic (sex and age) and clinical (main diagnosis, baseline area, and PU perimeter) differences between the groups. During the study period, there were no significant differences in the relative healing rates and PUSH scores between the subpopulations. The median time to complete healing in the study and control populations was 170.0 days (95% confidence interval [CI], 85.7-254.3) and 218.0 days (95% CI, 149.2-286.7) (log-rank, chi-square=3.99; p<0.046), respectively.

CONCLUSION

More than 20 weeks of HMB/Arg/Gln supplementation had a positive effect on difficult PU healing in older adults with multiple comorbidities.

Do oral amino acid supplements facilitate the healing of rat lung injuries?

OBJECTIVES

Prolonged air leaks following lung injury cause extended hospital stays. This study investigated the effect of nutritional supplements containing arginine, glutamine and β-hydroxy β-methyl butyrate, which were theoretically proven to accelerate wound healing, on air leak and wound healing parameters in a rat lung injury model.

METHODS

Twenty-eight female rats were randomly divided into 4 groups. Experimental groups were given glutamine (Resource Glutamine®) or a mixture of arginine, glutamine and β-hydroxy β-methyl butyrate (Abound®) as a dietary supplement at isonitrogenous and isocaloric doses. On day 3, standard sized lung injuries were created in all rats except the sham group. The rats were sacrificed on day 6, and the lungs were removed for air-leak threshold pressure measurement and histopathological and biochemical analyses.

RESULTS

Loss of body mass was greater in the glutamine group than in the other groups (P = 0.004). Rats that received the amino acid mixture had better results for mature collagen fibre density (P = 0.002) and inflammation suppression (P = 0.003). The sham group had higher values for air-leak threshold pressure and all other histochemical parameters compared to the other groups. Hydroxyproline level did not differ significantly in any of the groups.

CONCLUSIONS

Our results indicated that an oral amino acid mixture was effective in the healing of lung injuries. Isolated glutamine supplementation had an adverse impact on body mass. Randomized clinical studies including larger series are needed. Hydroxyproline does not seem to be a suitable marker for this purpose.

The effects of dietary/herbal supplements and the serum levels of micronutrients on the healing of diabetic foot ulcers in animal and human models: a systematic review

PURPOSE

Diabetic Foot Ulcer (DFU) is one of the common and serious complications in patients with Diabetes Mellitus (DM) worldwide. Given the considerable tendency of patients suffering from DFU to use the complementary therapies, the objectives of this study were to: (i) summarize the effects of dietary and herbal supplements on DFU characteristics and metabolic parameters in both animal models and clinical trials, and (ii) evaluate any links between the serum levels of micronutrients and DFU in observational studies.

METHODS

A systematic search in five electronic databases including PubMed/Medline, Scopus, Web of Science, Embase, and Cochrane Library was conducted to find relevant English language published from 1990 until 31 December 2018.

RESULTS

Of a total of 8603 studies, 30 eligible papers including animal studies (n = 15), clinical trials (n = 7), and observational works (n = 8) were included in the systematic review. We found that some dietary/herbal supplements and micronutrients had positive effects on the wound healing. However, limited evidence is existed. Also, lower serum levels of vitamin D, C, vitamin E, and selenium in patients with DFU were likely to increase the risk of DFU, leading to impaired wound healing.

CONCLUSION

Findings suggested that some dietary and herbal supplements such as Vitamin D, Magnesium, Vitamin E, Probiotic, Zinc, and Pycnogenol would be effective on wound healing of DFUs. However, further high-quality randomized controlled clinical trials and prospective cohort studies are needed to clarify the roles of micronutrients and other dietary and herbal supplements on the progress and treatment of DFU.

Photobiomodulation therapy was more effective than photobiomodulation plus arginine on accelerating wound healing in an animal model of delayed healing wound

The combined and individual influences of photobiomodulation therapy (PBMT) and arginine on wound strength, stereological parameters, and gene expressions of some related growth factors in ischemic and delayed healing wounds in rats were analyzed. We divided 108 rats into six groups: control, lower energy density (LOW)-PBMT, 2% arginine ointment (Arg 2%), LOW-PBMT + Arg 2%, high energy density (HIGH)-PBMT, and HIGH-PBMT + Arg 2%. First, we generated an ischemic and delayed healing wound model in each rat. We examined wound strength, stereological parameters, and gene expressions of basic fibroblast growth factor (bFGF), vascular endothelial growth factor A (VEGF-A), and stromal cell-derived factor 1 (SDF-1) by quantitative real-time polymerase chain reaction (qRT-PCR). PBMT alone and PBMT + Arg 2% considerably increased wound strength compared to the control and Arg 2% groups during the inflammatory and proliferative steps of wound healing (p < 0.05). In these steps, PBMT alone significantly induced an anti-inflammatory effect and increased fibroblast counts; Arg 2% alone induced an inflammatory response (p < 0.05). Concurrently, PBMT and PBMT + Arg 2% significantly increased keratinocyte counts and volume of the new dermis (p < 0.05). At the remodeling step, the Arg 2% groups had significantly better wound strength than the other groups (p < 0.05). In this step, PBMT and PBMT + Arg 2% significantly decreased inflammation, and increased fibroblast counts, vascular length, and the volume of new epidermis and dermis compared to the control and Arg 2% groups (p < 0.05). In all cases of gene analysis, there were statistically better results in the PBMT and PBMT + Arg 2% groups compared with the Arg 2% and control groups (p < 0.05). The anti-inflammatory and repairing effects of PBMT on an ischemic and delayed healing wound model in rats were shown by significant improvements in wound strength, stereological parameters, and gene expressions of bFGF, VEGF-A, and SDF-1α.

Immunonutritional support as an important part of multidisciplinary anti-cancer therapy

Immunonutrition is one of the most important parts of nutritional treatment in patients with cancer. There are studies which confirm positive effects of using immunonutrition (arginine, glutamine, omega-3 fatty acids, nucleotides, pre- and probiotics) among others on the reduction of the pro-inflammatory cytokines concentrations, shortening of the hospital stay and improvement of the nutritional status. Arginine takes part not only in wound healing process, but also it improves body’s immunity and reduces the incidence of infections. Glutamine reduces the incidence of acute grade 2 and 3 esophagitis and improves quality of life of gastric cancer patients. Omega 3-fatty acids have the ability to inhibit the activity of NF-κB. They also reduce the symptoms of graft-versus-host disease in patients undergoing hematopoietic cell transplantation. Nucleotides support the regeneration of intestinal villi. Probiotics play many roles, mainly inhibit the process of carcinogenesis, reduce the incidence of diarrhea and modify intestinal microbiome. However, there are studies indicating the lack of advantages of using immunonutrition compared to standard nutrition. Currently, there is no clear evidence for the use of formulae enriched with immunonutrients versus standard oral nutritional supplements exclusively in the preoperative period. This review summarizes the current knowledge about the role of immunonutrition in supporting treatment of cancer diseases.

The relationship between plasma amino acids and circulating albumin and haemoglobin in postabsorptive stroke patients

Background

This retrospective study had two main aims: (1) to document possible correlations between plasma Amino Acids (AAs) and circulating Albumin (Alb) and Haemoglobin (Hb); and (2) to identify which AAs were predictors of Alb and Hb.

Methods

The study considered 125 stroke subjects (ST) (61.6% males; 65.6 +/- 14.9 years) who met the eligibility criteria (absence of co morbidities associated with altered plasma AAs and presence of plasma AAs determined after overnight fasting). Fifteen matched healthy subjects with measured plasma AAs served as controls.

Results

The best correlations of Alb were with tryptophan (Trp) and histidine (His) (r = + 0.53; p < 0.0001), and those of Hb were with histidine (r = +0.47) and Essential AAs (r = +0.47) (both p<0.0001). In multivariate analysis, Trp (p< 0.0001) and His (p = 0.01) were shown to be the best positive predictors of Alb, whereas glutamine (p = 0.006) was the best positive predictor of Hb.

Conclusions

The study shows that the majority of plasma AAs were positively correlated with Alb and Hb. The best predictors of circulating Alb and Hb were the levels of tryptophan and glutamine, respectively.

Parenteral amino acid supplementation with high-dose insulin prevents hypoaminoacidemia during cardiac surgery

OBJECTIVES

Surgery triggers a stress response that produces insulin resistance and hyperglycemia. During cardiac surgery, the administration of high-dose insulin along with dextrose titration maintains normoglycemia, but dramatically decreases plasma amino acids (AAs) compared with preoperative fasting levels. Hypoaminoacidemia limits protein synthesis and prevents anabolic responses after surgery. We investigated whether parenteral infusion of AAs during and immediately after cardiac surgery would prevent hypoaminoacidemia in patients who receive high-dose insulin therapy.

METHODS

Sixteen patients undergoing coronary artery bypass grafting surgery were randomly allocated to receive AAs with % kcal equivalent to either 20% (n = 8) or 35% (n = 8) of their measured resting energy expenditure (REE). Insulin was infused at a constant rate of 5 mU/(kg × min), whereas dextrose was titrated to maintain normoglycemia during and until 5 h after surgery. Plasma AA concentrations were measured at baseline before and after surgery.

RESULTS

Compared with the 20% AA group after surgery, AA concentrations were significantly higher in the 35% AA group for 12 of 20 AAs (P < 0.032), including all branched-chain AAs. In the 20% AA group, total essential AAs decreased by 21% and nonessential AAs decreased by 14% after surgery compared with preoperative fasting levels. In contrast, giving 35% AAs prevented this unfavorable decrease in AAs, and in fact allowed for a 23% and 12% increase in essential and nonessential AAs, respectively.

CONCLUSIONS

AA supplementation at 35% REE, but not 20% REE, can effectively prevent hypoaminoacidemia caused by high-dose insulin therapy during cardiac surgery.

Proline Precursors and Collagen Synthesis: Biochemical Challenges of Nutrient Supplementation and Wound Healing

Wound healing is a complex process marked by highly coordinated immune fluxes into an area of tissue injury; these are required for re-establishment of normal tissue integrity. Along with this cascade of cellular players, wound healing also requires coordinated flux through a number of biochemical pathways, leading to synthesis of collagen and recycling or removal of damaged tissues. The availability of nutrients, especially amino acids, is critical for wound healing, and enteral supplementation has been intensely studied as a potential mechanism to augment wound healing-either by increasing tensile strength, decreasing healing time, or both. From a practical standpoint, although enteral nutrient supplementation may seem like a reasonable strategy to augment healing, a number of biochemical and physiologic barriers exist that limit this strategy. In this critical review, the physiology of enteral amino acid metabolism and supplementation and challenges therein are discussed in the context of splanchnic physiology and biochemistry. Additionally, a review of studies examining various methods of amino acid supplementation and the associated effects on wound outcomes are discussed.

Therapeutic effectiveness of instrument-assisted soft tissue mobilization for soft tissue injury: mechanisms and practical application

This article reviews the mechanism and effects of instrument-assisted soft tissue mobilization (IASTM), along with guidelines for its practical application. IASTM refers to a technique that uses instruments to remove scar tissues from injured soft tissues and facilitate healing process through formation of new extracellular matrix proteins such as collagen. Recently, frequent use of this instrument has increased in the fields of sports rehabilitation and athlete training. Some experimental studies and case reports have reported that IASTM can significantly improve soft tissue function and range of motion following sports injury, while also reducing pain. Based on the previous studies, it is thought that IASTM can help shorten the rehabilitation period and time to return to sports among athletes and ordinary people who have suffered sports injuries. However, few experimental studies of the mechanisms and effects of IASTM have examined, while case reports have accounted for the majority of articles. In the future, the scientific basis of IASTM and its reliability should be provided through well-designed experimental studies on humans. Moreover, IASTM studies that have mostly focused on tendons need to broaden their scope toward other soft tissues such as muscles and ligaments.