Methylglyoxal-a potential risk factor of manuka honey in healing of diabetic ulcers

Absorption and intracellular accumulation of food-borne dicarbonyl precursors of advanced glycation end-product in a Caco-2 human cell transwell model

This study aimed to better understand whether and how the reactive 1,2-dicarbonyl precursors of advanced glycation end products (AGEs), glyoxal (GO) and methylglyoxal (MGO), cross the intestinal barrier by studying their transport in the in vitro Caco-2 transwell system. The results reveal that GO, MGO and Nε-(carboxymethyl)lysine (CML), the latter studied for comparison, are transported across the intestinal cell layer via both active and passive transport and accumulate in the cells, albeit all to a limited extent. Besides, the transport of the dicarbonyl compounds was only partially affected by the presence of amino acids and protein, suggesting that scavenging by a food matrix will not fully prevent their intestinal absorption. Our study provides new insights into the absorption of the two major food-borne dicarbonyl AGE precursors and provides evidence of their potential systemic bioavailability but also of factors limiting their contribution to the overall exposome.

The Antioxidant Potential of Commercial Manuka Honey from New Zealand-Biochemical and Cellular Studies

Manuka honey (MH) is considered a superfood mainly because of its various health-promoting properties, including its anti-cancer, anti-inflammatory, and clinically proven antibacterial properties. A unique feature of Manuka honey is the high content of methylglyoxal, which has antibacterial potential. Additionally, it contains bioactive and antioxidant substances such as polyphenols that contribute to its protective effects against oxidative stress. In this study, commercially available Manuka honey was tested for its total polyphenol content and DPPH radical scavenging ability. It was then tested in vitro on human fibroblast cells exposed to UV radiation to assess its potential to protect cells against oxidative stress. The results showed that the honey itself significantly interfered with cell metabolism, and its presence only slightly alleviated the effects of UV exposure. This study also suggested that the MGO content has a minor impact on reducing oxidative stress in UV-irradiated cells and efficiency in scavenging the DPPH radical.

Quality of Commercially Available Manuka Honey Expressed by Pollen Composition, Diastase Activity, and Hydroxymethylfurfural Content

Manuka honey plays a significant role in modern medical applications as an antibacterial, antiviral, and antibiotic agent. However, although the importance of manuka honey is well documented in the literature, information regarding its physicochemical characteristics remains limited. Moreover, so far, only a few papers address this issue in conjunction with the examination of the pollen composition of manuka honey samples. Therefore, in this study, two parameters crucial for honey quality control-the diastase number (DN) and the hydroxymethylfurfural (HMF) content-as well as the melissopalynological analysis of manuka honey, were examined. The research found a large variation in the percentage of Leptospermum scoparium pollen in honeys labeled and sold as manuka honeys. Furthermore, a significant proportion of these honeys was characterized by a low DN. However, since low diastase activity was not associated with low HMF content, manuka honey should not be considered as a honey with naturally low enzymatic activity. Overall, the DN and HMF content results indicate that the quality of commercially available manuka honey is questionable.

Use of honey in diabetic foot ulcer: Systematic review and meta-analysis

OBJECTIVE

The aim of this study was to evaluate the role of honey dressing as an effective intervention for diabetic foot wound management and to provide a reliable basis for future clinical study.

MATERIALS AND METHODS

We analyzed an assortment of randomized controlled trial (RCT), quasi-experimental and cross-sectional studies. We selected RCTs and quasi-experimental studies for meta-analysis. We only conducted a descriptive analysis for observational studies.

RESULTS

The meta-analysis showed that honey used effectively reduces wound recovery time and rate, incurred pain, hospital stay, and accelerates granulation in DFU wounds.

CONCLUSIONS

Our findings suggest that honey effectively promotes healing in DFU. Further research is needed to elucidate these findings so that this form of treatment can be widely applied.

Polysucrose hydrogel loaded with natural molecules/extracts for multiphase-directed sustainable wound healing

Natural molecules/extracts have numerous beneficial effects on wound healing processes which are challenged by appropriate use and non-toxic dosage. Polysucrose-based (PSucMA) hydrogels have been synthesized with in situ loading of one or more natural molecules/extracts namely Manuka honey (MH), Eucalyptus honey (EH1, EH2), Ginkgo biloba (GK), thymol (THY) and metformin (MET). EH1 presented low amounts of hydroxymethylfurfural and methylglyoxal compared to MH indicating that EH1 was not temperature-abused. It also showed high diastase activity and conductivity. GK was added to PSucMA solution along with other additives including MH, EH1 and MET and crosslinked to form dual loaded hydrogels. The in vitro release profiles of EH1, MH, GK and THY from the hydrogels followed the exponential Korsmeyer-Peppas equation, with a release exponent value of less than 0.5 indicating a quasi-Fickian diffusion mechanism. The IC50 values of these natural products using L929 fibroblasts and RAW 264.7 macrophages indicated that EH1, MH and GK were cytocompatible at relatively high concentrations compared to MET, THY and curcumin used as a control. MH and EH1 induced high IL6 concentration compared to GK. In vitro studies were modelled to mimic the overlapping wound healing phases using human dermal fibroblasts (HDFs), macrophages and human umbilical endothelial cells (HUVECs) in dual culture. HDFs showed a highly interconnected cellular network on GK loaded scaffolds. EH1 loaded scaffolds were seen to induce formation of spheroids which increased in number and size in co-culture studies. The SEM images of HDF/HUVEC seeded GK, GKMH and GKEH1 loaded hydrogels indicated formation of vacuoles and lumen structures. These results indicated that a combination of GK and EH1 in the hydrogel scaffold would accelerate tissue regeneration by acting on the four overlapping phases of wound healing.

A critical review on nanomaterial based therapeutics for diabetic wound healing

Diabetes mellitus is a chronic endocrine disease that occurs mostly in the state of hyperglycemia (elevated blood glucose level). In the recent times, diabetes is listed under world's utmost critical health issues. Wound treatment procedures are complicated in diabetic individuals all over the world. Diabetic wound care not only involves high-cost, but also the primary cause of hospitalization, which can lead to amputation thereby reducing diabetic patient life expectancy. To lower the risk of amputation, wound healing requires the development of effective treatments. Traditional management systems for Diabetes are frequently chastised due to their high costs, difficulties in maintaining a sustainable supply chain and limited disposal alternatives. The worrisome rise in diabetes prevalence has sparked a surge of interest in the discovery of viable remedies to supplement existing treatments. Nanomaterials wound healing has a lot of potential for treating and preventing wound infections and it has recently gained popularity owing to its ability to transport drugs to the wound area in a regulated fashion, potentially overpowering the limits of traditional approaches. This research assessed several nanosystems, such as nanocarriers and nanotherapeutics, to explore how they can benefit in diabetic wound healing, with a focus on current obstacles and future prospects.

Antibacterial Efficacy and Healing Potential of Honey from Different Zones in Nigeria on Diabetic-Induced Wound Infection in Wistar Rats

There is an increase in drug-resistant strains causing infection, thus making available therapeutics less effective. As resistance increases, modern medicine focuses on the antibacterial potential of natural products, which can aid in wound healing. The present study determined Nigeria honey's antibacterial efficacy in treating diabetes-induced wound infections in Wistar albino rats. 54 Wistar rats randomly divided into 9 groups of 6 each were used for the study: group I (negative control, no treatment), group II (positive control, diabetes without treatment), group III (diabetes treated with 1% silver sulfadiazine), and groups IV–IX (diabetes treated with different honey samples). Physiochemical analysis and microbiological and antibacterial activity of the honey samples were determined. The treatments were carried out for 17 days, and wound contraction, malondialdehyde (MDA) levels, and catalase activity were measured. Results obtained showed that the most effective honey was DCH (21.5 ± 2.12), followed by HBP + M (15 ± 2.12) and TRB, JS, and HBP (13 ± 2.8; 13 ± 1.41; 13.5 ± 0.71) for antibacterial activity on Staphylococcus aureus. Microbiologically, no coliform was detected in all the samples, confirming the honey's quality. The amount of lipid peroxidation was raised in the diabetic group with no treatment, 1% silver sulfadiazine group, and JS group, while no significant reduction was observed in other groups. Differences in wound contraction were significantly notable on various days of measurement, day 3 (p < 0.002), day 6 (p < 0.046), and day 9 (p = 0.00). The catalase level in the different treatment groups increased significantly (p < 0.05), implying an antioxidant potential of the different honey samples except for Jos honey. The study concludes that honey infused with moringa was faster and more efficient in healing diabetic wounds than other honey samples and silver sulfadiazine.

Antibacterial interactions between two monofloral honeys and several topical antiseptics, including essential oils

Background

Honey has broad spectrum antibacterial activity against clinically important organisms and may be suitable for treating superficial bacterial infections. However, very little data are available describing potential interactions between honey and other topically applied agents such as antiseptics or essential oils.

Methods

Interactions between pairs of antibacterial agents were investigated by performing checkerboard assays and determining the fractional inhibitory concentration indices (FICIs). Interactions between the two monofloral honeys marri (from Corymbia calophylla) and manuka, and the antiseptic agents benzalkonium chloride, chlorhexidine digluconate, silver (I) nitrate, tea tree oil, and Eucalyptus polybractea oil were investigated against Staphylococcus aureus ATCC® 43300 and Pseudomonas aeruginosa ATCC® 27853.

Results

Additive or indifferent interactions (FICI 0.5—2) were observed for all combinations against both organisms tested, with the exception of chlorhexidine and honey. Chlorhexidine and marri honey showed an antagonistic relationship against S. aureus (median FICI 2.00, range 1.25—4.83). Similarly, chlorhexidine and manuka honey showed antagonism against S. aureus (median FICI 2.33, range 2.00—2.67).

Conclusions

With the exception of chlorhexidine, these data indicate that honey does not interfere with the antimicrobial activity of the tested agents, and that honey may be suitable for combination therapy with other topically applied antibacterial agents for treating superficial bacterial infections.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-022-03695-x.

A Comprehensive Review of Natural Compounds for Wound Healing: Targeting Bioactivity Perspective

Wound healing is a recovering process of damaged tissues by replacing dysfunctional injured cellular structures. Natural compounds for wound treatment have been widely used for centuries. Numerous published works provided reviews of natural compounds for wound healing applications, which separated the approaches based on different categories such as characteristics, bioactivities, and modes of action. However, current studies provide reviews of natural compounds that originated from only plants or animals. In this work, we provide a comprehensive review of natural compounds sourced from both plants and animals that target the different bioactivities of healing to promote wound resolution. The compounds were classified into four main groups (i.e., anti-inflammation, anti-oxidant, anti-bacterial, and collagen promotion), mostly studied in current literature from 1992 to 2022. Those compounds are listed in tables for readers to search for their origin, bioactivity, and targeting phases in wound healing. We also reviewed the trend in using natural compounds for wound healing.

Honey: An Advanced Antimicrobial and Wound Healing Biomaterial for Tissue Engineering Applications

Honey was used in traditional medicine to treat wounds until the advent of modern medicine. The rising global antibiotic resistance has forced the development of novel therapies as alternatives to combat infections. Consequently, honey is experiencing a resurgence in evaluation for antimicrobial and wound healing applications. A range of both Gram-positive and Gram-negative bacteria, including antibiotic-resistant strains and biofilms, are inhibited by honey. Furthermore, susceptibility to antibiotics can be restored when used synergistically with honey. Honey’s antimicrobial activity also includes antifungal and antiviral properties, and in most varieties of honey, its activity is attributed to the enzymatic generation of hydrogen peroxide, a reactive oxygen species. Non-peroxide factors include low water activity, acidity, phenolic content, defensin-1, and methylglyoxal (Leptospermum honeys). Honey has also been widely explored as a tissue-regenerative agent. It can contribute to all stages of wound healing, and thus has been used in direct application and in dressings. The difficulty of the sustained delivery of honey’s active ingredients to the wound site has driven the development of tissue engineering approaches (e.g., electrospinning and hydrogels). This review presents the most in-depth and up-to-date comprehensive overview of honey’s antimicrobial and wound healing properties, commercial and medical uses, and its growing experimental use in tissue-engineered scaffolds.

Multifloral white honey outclasses manuka honey in methylglyoxal content: assessment of free and encapsulated methylglyoxal and anti-microbial peptides in liposomal formulation against toxigenic potential of Bacillus subtilis Subsp spizizenii strain

The therapeutic virtues of honey no longer need to be proven. Honey, which is rich in nutrients, is an excellent nutritional food because of its many properties; however, honey has been diverted from this primary function and used in clinical research. Evidence has shown that honey still possesses unknown properties and some of these aspects have never been addressed. In this work, two bioactive compounds found in honey (methylglyoxal and antimicrobial peptides) were evaluated for their anti-Bacillus subtilis activity with particular attention to their dilution factor. Although this bacterial strain does not possess an indigenous virulence factor gene, it becomes virulent by transferring plasmids with B. thuringiensis or expression of toxins from Bordetella pertussis. As is known, methylglyoxal is a toxic electrophile present in many eukaryotic and prokaryotic cells, which is generated by enzymatic and non-enzymatic reactions. Its overexpression successfully kills bacteria by inducing membrane disruption. Also, AMPs show potent inhibitory action against Gram-positive bacteria. Because of the lack of information concerning the main ingredients of honey, the microencapsulation process was used. Both methylglyoxal (MGO) and peptide-loaded liposomes were synthesized, characterized and compared to their free forms. The liposomal formulations contained a mixture of eggPC, cholesterol, and octadecylamine and their particle sizes were measured and their encapsulation efficacy calculated. The results revealed that Algerian multifloral white honey contained higher levels of MGO compared to manuka honey, which prevented bacterial growth and free MGO was relatively less effective. In fact, MGO killed BS in the loaded form with the same bacteriostatic and bactericidal index. However, the action of AMPs was different. Indeed, the investigation into the reactivity of MGO in the solvent indicated that regardless of the level of water added, honey is active at a fixed dilution. This data introduces the notion of dilution and abolishes the concept of concentration. Moreover, the synergistic antibacterial effect of the compounds in honey was diminished by the matrix effect. The degree of liposome-bacteria-fusion and the delay effect observed could be explain by both the composition and nature of the lipids used. Finally, this study reinforces the idea that under certain conditions, the metalloproteinases in honey produce AMPs.

Applications of Alginate-Based Nanomaterials in Enhancing the Therapeutic Effects of Bee Products

Since the ancient times, bee products (i.e., honey, propolis, pollen, bee venom, bee bread, and royal jelly) have been considered as natural remedies with therapeutic effects against a number of diseases. The therapeutic pleiotropy of bee products is due to their diverse composition and chemical properties, which is independent on the bee species. This has encouraged researchers to extensively study the therapeutic potentials of these products, especially honey. On the other hand, amid the unprecedented growth in nanotechnology research and applications, nanomaterials with various characteristics have been utilized to improve the therapeutic efficiency of these products. Towards keeping the bee products as natural and non-toxic therapeutics, the green synthesis of nanocarriers loaded with these products or their extracts has received a special attention. Alginate is a naturally produced biopolymer derived from brown algae, the desirable properties of which include biodegradability, biocompatibility, non-toxicity and non-immunogenicity. This review presents an overview of alginates, including their properties, nanoformulations, and pharmaceutical applications, placing a particular emphasis on their applications for the enhancement of the therapeutic effects of bee products. Despite the paucity of studies on fabrication of alginate-based nanomaterials loaded with bee products or their extracts, recent advances in the area of utilizing alginate-based nanomaterials and other types of materials to enhance the therapeutic potentials of bee products are summarized in this work. As the most widespread and well-studied bee products, honey and propolis have garnered a special interest; combining them with alginate-based nanomaterials has led to promising findings, especially for wound healing and skin tissue engineering. Furthermore, future directions are proposed and discussed to encourage researchers to develop alginate-based stingless bee product nanomedicines, and to help in selecting suitable methods for devising nanoformulations based on multi-criteria decision making models. Also, the commercialization prospects of nanocomposites based on alginates and bee products are discussed. In conclusion, preserving original characteristics of the bee products is a critical challenge in developing nano-carrier systems. Alginate-based nanomaterials are well suited for this task because they can be fabricated without the use of harsh conditions, such as shear force and freeze-drying, which are often used for other nano-carriers. Further, conjunction of alginates with natural polymers such as honey does not only combine the medicinal properties of alginates and honey, but it could also enhance the mechanical properties and cell adhesion capacity of alginates.

Therapy of infected wounds: overcoming clinical challenges by advanced drug delivery systems

In recent years, the incidence of infected wounds is steadily increasing, and so is the clinical as well as economic interest in effective therapies. These combine reduction of pathogen load in the wound with general wound management to facilitate the healing process. The success of current therapies is challenged by harsh conditions in the wound microenvironment, chronicity, and biofilm formation, thus impeding adequate concentrations of active antimicrobials at the site of infection. Inadequate dosing accuracy of systemically and topically applied antibiotics is prone to promote development of antibiotic resistance, while in the case of antiseptics, cytotoxicity is a major problem. Advanced drug delivery systems have the potential to enable the tailor-made application of antimicrobials to the side of action, resulting in an effective treatment with negligible side effects. This review provides a comprehensive overview of the current state of treatment options for the therapy of infected wounds. In this context, a special focus is set on delivery systems for antimicrobials ranging from semi-solid and liquid formulations over wound dressings to more advanced carriers such as nano-sized particulate systems, vesicular systems, electrospun fibers, and microneedles, which are discussed regarding their potential for effective therapy of wound infections. Further, established and novel models and analytical techniques for preclinical testing are introduced and a future perspective is provided.

Honey-incorporated nanofibre reduces replicative senescence of umbilical cord-derived mesenchymal stem cells

Umbilical cord-derived mesenchymal stem cells (UCDMSC) are attractive candidates for cell-based regenerative medicine. However, they are susceptible to replicative senescence during repetitive passaging for in-vitro expansion and induced senescence in an oxidative, inflammatory microenvironment in vivo. Aim of this study is to investigate if honey-incorporated matrices can be employed to reduce senescence of UCDMSC. Matrices were prepared by electrospinning solutions of honey with poly-vinyl alcohol (PVA). PVA:honey matrices exhibited free radical scavenging activity. Culture of UCDMSC on PVA:honey matrices showed improvement in cell proliferation compared to pure PVA nanofibres. Expression of vimentin indicated that mesenchymal phenotype is preserved after culturing on these matrices. Further, UCDMSC were serially subcultured and cells of two passages (P2 and P6) were evaluated for reactive oxygen species (ROS) load and senescence parameters. P6 cells showed a higher ROS load and β-galactosidase (β-gal) positive senescent cells compared to P2. However, culturing on PVA:honey substrates significantly reduced both ROS and β-gal markers compared to cells on PVA substrates. Honey contains several antioxidant and anti-inflammatory components, which can reduce the ROS-related senescence. Thus, it is concluded that honey containing nanofibres can be effective substrates for stem cell-based wound healing and regenerative medicine.

Manuka honey microneedles for enhanced wound healing and the prevention and/or treatment of Methicillin-resistant Staphylococcus aureus (MRSA) surgical site infection

Manuka honey (MH) is currently used as a wound treatment and suggested to be effective in Methicillin-resistant Staphylococcus aureus (MRSA) elimination. We sought to optimize the synthesis of MH microneedles (MHMs) while maintaining the MH therapeutic effects. MHMs were synthesized using multiple methods and evaluated with in vitro assays. MHMs demonstrated excellent bactericidal activity against MRSA at concentrations ≥ 10% of honey, with vacuum-prepared honey appearing to be the most bactericidal, killing bacterial concentrations as high as 8 × 10⁷ CFU/mL. The wound-healing assay demonstrated that, at concentrations of 0.1%, while the cooked honey had incomplete wound closure, the vacuum-treated honey trended towards faster wound closure. In this study, we demonstrate that the method of MHM synthesis is crucial to maintaining MH properties. We optimized the synthesis of MHMs and demonstrated their potential utility in the treatment of MRSA infections as well as in wound healing. This is the first report of using MH as a substrate for the formation of dissolvable microneedles. This data supports the need for further exploration of this new approach in a wound-healing model and opens the door for the future use of MH as a component of microneedle scaffolds.

Methylglyoxal: Antimicrobial activity against blood culture isolates of Salmonella Typhi and other Gram negative rods

Objectives:

To evaluate the activity of Methylglyoxal against the blood culture isolates of Salmonella Typhi and various Gram negative rods and to compare the activity of Methylglyoxal against S. Typhi and other Gram negative rods.

Methods:

It was an experimental study conducted at the Department of Microbiology, University of Health Sciences (UHS), Lahore-Pakistan in collaboration with the Department of Microbiology, CMH Lahore, from July 2011 to June 2012. Recent blood culture isolates of S. Typhi and other Gram negative rods were collected from different hospitals of Lahore and kept stored at -80°C. As per the latest CLSI guidelines, morphological, biochemical and serological identification was carried out and antimicrobial susceptibility was tested. A multi-point inoculator was used to carry out agar dilution for determination of MICs of MGO. Results were determined after compilation of data using latest SPSS version.

Results:

MIC₉₀ of MGO against the clinical isolates of S. Typhi was 0.20 mg/mL (2.8 mM) and against Gram negative rods it was 0.21 mg/mL (3.0 mM). The p-value of MICs of MGO against the isolates of S. Typhi was 0.023 when compared with Gram negative rods (p<0.05; statistically significant).

Conclusion:

MGO has a scientifically proven in vitro antimicrobial activity against blood culture isolates of S. Typhi and various Gram negative rods.

Medicinal honey in clinical practice: viable alternative or useful adjunct in wound care management?

In light of concerns raised about antimicrobial resistance, especially in hospitals, and the rise in bacteria that are resistant to antibiotics scientists are examining alternative sources and strategies to combat infection. Among the plethora of complementary medicines now being considered is honey, particularly manuka honey. Medicinal honey is a relatively new label given to some types of honey that have been shown to be effective antimicrobial agents in in vitro studies. Large-scale clinical trials are yet to be conducted but there is considerable interest and numerous case studies that demonstrate the benefits of medicinal honey, especially in wound healing.

Comparative Evaluation of Wound Healing Potential of Manuka and Acacia Honey in Diabetic and Nondiabetic Rats

Background

Manuka honey has attracted the attention of the scientific community for its antimicrobial and antioxidant properties. The active compounds of manuka honey to which its myeloperoxidase activity inhibition is owed are methyl syringate (MSYR) and leptosin (a novel glycoside of MSYR). The non-peroxide antibacterial activity is attributed to glyoxal, 3-deoxyglucosulose, and methylglyoxal. These properties make it an inexpensive and effective topical treatment in wound management. This study has focused on the evaluation of the effect of manuka honey and acacia honey on wound healing in nondiabetic and streptozotocin-induced diabetic rats.

Materials and Methods

This study was conducted on a total of 42 rats (six rats in each group) and respective drug/substance was topically applied once daily on the excision wound for 21 days. Induction of diabetes was carried out in rats in groups IV, V, VI, and VII only. Measurement of wound contraction was carried out on days 3, 6, 9, 12, 15, 18, and 21 after operation. Time taken for the complete epithelization was recorded along with a histopathological examination of the healed wound bed.

Results

Topical application of manuka honey achieved ≥80% wound contraction on day 9 after operation in both the nondiabetic and diabetic group. Complete epithelization was achieved 2 days earlier than the normal epithelization time in the manuka group. Histopathological examination showed well-formed keratinized squamous epithelium with normal collagen tissue surrounding hair follicles.

Conclusion

This study provides good outcome with respect to wound healing (especially in diabetic condition) when manuka honey was compared to acacia honey and standard treatment.

Honey protects against cisplatin-induced hepatic and renal toxicity through inhibition of NF-κB-mediated COX-2 expression and the oxidative stress dependent BAX/Bcl-2/caspase-3 apoptotic pathway

The protective effects of both manuka and talh honeys were assessed using a rat model of cisplatin (CISP)-induced hepatotoxicity and nephrotoxicity. The results revealed that both honeys exerted a protective effect against CISP-induced hepatotoxicity and nephrotoxicity as demonstrated by decreasing liver and kidney function. Manuka honey also prevented CISP-induced histopathological changes observed in the liver and decreased the changes seen in the kidneys. Talh honey decreased CISP-induced liver histopathological changes but had no effect on CISP-induced kidney histopathological changes. Both honeys reduced the oxidative stress in the liver. Conversely, they have no effect on kidney oxidative stress, except that manuka honey increased CAT activity. GC-MS analysis showed the presence of the antioxidant octadecanoic acid in talh honey while heneicosane and hydrocinnamic acid were present at a higher content in manuka honey. The molecular mechanism was to limit the expression of inflammatory signals, including COX-2 and NF-κB, and the expression of the apoptotic signal, BAX and caspase-3 while inducing Bcl-2 expression.

Topical 5% potassium permanganate solution accelerates the healing process in chronic diabetic foot ulcers

Potassium permanganate has been reported to be an effective treatment for certain types of wounds. The aim of the present study was to evaluate the use of potassium permanganate in the treatment of diabetic foot ulcers. A single-blind, randomized, controlled clinical trial was conducted on patients with type 2 diabetes mellitus that presented with a foot ulcer persisting for >3 months. The control group (n=10) was treated with the current standard treatment, which comprises of measures for reducing pressure in the ulcerated area, daily cleansing of the ulcer with potable water and antiseptic wash solution, and the application of a disinfectant solution on the entire surface area of the ulcer; while the intervention group (n=15) received the standard treatment plus 5% topical potassium permanganate solution applied once a day for 21 days. In the intervention group, 1 patient did not tolerate the treatment and was eliminated from the study on the first day. The remaining patients tolerated the interventions well. At the end of the treatment period, ulcers in the control group had decreased by 38% whereas those in the intervention group decreased by 73% (P<0.009). The degree of decrease was also investigated; the ulcer size was ≥50% decreased in 40% of patients in the control group and in 86% of patients in the intervention group (P=0.02). In conclusion, the results of the present study indicate that topical potassium permanganate is well tolerated and significantly accelerates the healing process of diabetic foot ulcers.

A Comprehensive Review of Topical Odor-Controlling Treatment Options for Chronic Wounds

The process of wound healing is often accompanied by bacterial infection or critical colonization, resulting in protracted inflammation, delayed reepithelization, and production of pungent odors. The malodor produced by these wounds may lower health-related quality of life and produce psychological discomfort and social isolation. Current management focuses on reducing bacterial activity within the wound site and absorbing malodorous gases. For example, charcoal-based materials have been incorporated into dressing for direct adsorption of the responsible gases. In addition, multiple topical agents, including silver, iodine, honey, sugar, and essential oils, have been suggested for incorporation into dressings in an attempt to control the underlying bacterial infection. This review describes options for controlling malodor in chronic wounds, the benefits and drawbacks of each topical agent, and their mode of action. We also discuss the use of subjective odor evaluation techniques to assess the efficacy of odor-controlling therapies. The perspectives of employing novel biomaterials and technologies for wound odor management are also presented.

Diversity Analysis and Bioresource Characterization of Halophilic Bacteria Isolated from a South African Saltpan

Though intensive research has been channeled towards the biotechnological applications of halophiles and other extremophilic microbes, these studies have not been, by any means, exhaustive. Saline environments still offer a vast diversity of microbes with potential to produce an array of natural products which can only be unlocked by concerted research efforts. In this study, a combination of culture and molecular approaches were employed to characterize halophilic bacteria from saltpan water samples and profile their potential biotechnological applications. Physicochemical analysis of the water samples showed that pH was alkaline (pH 8.8), with a salinity of 12.8%. 16S rRNA gene targeted amplicon analysis produced 10 bacterial phyla constituting of Bacteroidetes (30.57%), Proteobacteria (15.27%), Actinobacteria (9.05%), Planctomycetes (5.52%) and Cyanobacteria (3.18%). Eighteen strains were identified using sequencing analysis of the culturable bacterial strains. From these, the strains SP7 and SP9 were positive for cellulase production while the strains SP4, SP8 and SP22 were positive for lipase production. Quantitative enzyme assays showed moderate extracellular cellulase activity (1.95 U/mL) and lipase activity (3.71 U/mL) by the isolate SP9 and SP4 respectively. Further, of the six isolates, the isolate SP9 exhibited exploitable potential in the bioremediation of hydrocarbon pollution as demonstrated by its fairly high activity against benzanthracene (70% DCPIP reduction). Elucidation of the isolates secondary metabolites showed the production of the molecules 2,3-butanediol, hexahydro-3-(2-methylpropyl)pyrrole[1,2a]pyrazine-1,4-dione, aziridine, dimethylamine and ethyl acetate (GC-MS) and oxypurinol and 5-hydroxydecanoic acid (LC-MS), particularly by the isolate Salinivibrio sp. SP9. Overall, the study showed that the isolated halophiles can produce secondary metabolites with potential industrial and pharmaceutical application.

Honey and Wound Healing: An Update

For centuries, honey has been utilized for wound healing purposes. In recent times, this specific topic has become a field of interest, possibly due to the advent of antibiotic resistance in microbial pathogens. With constant technological advancement, the information regarding honey's mechanisms of action on wound healing has accumulated at a rapid pace. Similarly, clinical studies comparing honey with traditional wound care therapies are steadily emerging. As a follow-up to a previous review published in the journal in 2011, the current review article outlines publications regarding honey and wound healing that have been published between June 2010 and August 2016. Here we describe the most recent evidence regarding multiple types of honey and their mechanisms of action as antimicrobial agents, immunologic modulators, and physiologic mediators. In addition, outcomes of clinical studies involving a multitude of cutaneous wounds are also examined.

Smart Dressings Based on Nanostructured Fibers Containing Natural Origin Antimicrobial, Anti-Inflammatory, and Regenerative Compounds

A fast and effective wound healing process would substantially decrease medical costs, wound care supplies, and hospitalization significantly improving the patients' quality of life. The search for effective therapeutic approaches seems to be imperative in order to avoid the aggravation of chronic wounds. In spite of all the efforts that have been made during the recent years towards the development of artificial wound dressings, none of the currently available options combine all the requirements necessary for quick and optimal cutaneous regeneration. Therefore, technological advances in the area of temporary and permanent smart dressings for wound care are required. The development of nanoscience and nanotechnology can improve the materials and designs used in topical wound care in order to efficiently release antimicrobial, anti-inflammatory and regenerative compounds speeding up the endogenous healing process. Nanostructured dressings can overcome the limitations of the current coverings and, separately, natural origin components can also overcome the drawbacks of current antibiotics and antiseptics (mainly cytotoxicity, antibiotic resistance, and allergies). The combination of natural origin components with demonstrated antibiotic, regenerative, or anti-inflammatory properties together with nanostructured materials is a promising approach to fulfil all the requirements needed for the next generation of bioactive wound dressings. Microbially compromised wounds have been treated with different essential oils, honey, cationic peptides, aloe vera, plant extracts, and other natural origin occurring antimicrobial, anti-inflammatory, and regenerative components but the available evidence is limited and insufficient to be able to draw reliable conclusions and to extrapolate those findings to the clinical practice. The evidence and some promising preliminary results indicate that future comparative studies are justified but instead of talking about the beneficial or inert effects of those natural origin occurring materials, the scientific community leads towards the identification of the main active components involved and their mechanism of action during the corresponding healing, antimicrobial, or regenerative processes and in carrying out systematic and comparative controlled tests. Once those natural origin components have been identified and their efficacy validated through solid clinical trials, their combination within nanostructured dressings can open up new avenues in the fabrication of bioactive dressings with outstanding characteristics for wound care. The motivation of this work is to analyze the state of the art in the use of different essential oils, honey, cationic peptides, aloe vera, plant extracts, and other natural origin occurring materials as antimicrobial, anti-inflammatory and regenerative components with the aim of clarifying their potential clinical use in bioactive dressings. We conclude that, for those natural occurring materials, more clinical trials are needed to reach a sufficient level of evidence as therapeutic agents for wound healing management.

The Anti-Inflammatory and Antibacterial Action of Nanocrystalline Silver and Manuka Honey on the Molecular Alternation of Diabetic Foot Ulcer: A Comprehensive Literature Review

Honey and silver have been used since ancient times for treating wounds. Their widespread clinical application has attracted attention in light of the increasing prevalence of antibiotic-resistant bacteria. While there have been a number of studies exploring the anti-inflammatory and antibacterial effects of manuka honey and nanocrystalline silver, their advantages and limitations with regard to the treatment of chronic wounds remain a subject of debate. The aim of this paper is to examine the evidence on the use of nanocrystalline silver and manuka honey for treating diabetic foot ulcers through a critical and comprehensive review of in vitro studies, animal studies, and in vivo studies. The findings from the in vitro and animal studies suggest that both agents have effective antibacterial actions. Their anti-inflammatory action and related impact on wound healing are unclear. Besides, there is no evidence to suggest that any topical agent is more effective for use in treating diabetic foot ulcer. Overall, high-quality, clinical human studies supported by findings from the molecular science on the use of manuka honey or nanocrystalline silver are lacking. There is a need for rigorously designed human clinical studies on the subject to fill this knowledge gap and guide clinical practice.

Honey in the Prevention and Treatment of Infection in the CKD Population: A Narrative Review

Infection is a major cause of morbidity and mortality at all stages of chronic kidney disease (CKD). Multiresistant organisms are becoming increasingly common, particularly in the CKD population. Unfortunately, the rapid evolution of antibiotic resistance has not been mirrored by innovation in new antibiotic agents. Novel treatments are therefore urgently needed. Honey has garnered much interest due to its broad-spectrum antibacterial properties based on extensive experimental data. Unlike conventional antibiotics, honey has an added advantage as it appears to avoid inducing antimicrobial resistance in bacteria. This review discusses the potential mechanisms of action and role of honey in infection management in the general population, epidemiology and special challenges of infections in CKD populations, and the clinical trial evidence pertaining to the safety and efficacy of honey for the prevention and treatment of infections in CKD population.

Honey: a potential therapeutic agent for managing diabetic wounds

Diabetic wounds are unlike typical wounds in that they are slower to heal, making treatment with conventional topical medications an uphill process. Among several different alternative therapies, honey is an effective choice because it provides comparatively rapid wound healing. Although honey has been used as an alternative medicine for wound healing since ancient times, the application of honey to diabetic wounds has only recently been revived. Because honey has some unique natural features as a wound healer, it works even more effectively on diabetic wounds than on normal wounds. In addition, honey is known as an "all in one" remedy for diabetic wound healing because it can combat many microorganisms that are involved in the wound process and because it possesses antioxidant activity and controls inflammation. In this review, the potential role of honey's antibacterial activity on diabetic wound-related microorganisms and honey's clinical effectiveness in treating diabetic wounds based on the most recent studies is described. Additionally, ways in which honey can be used as a safer, faster, and effective healing agent for diabetic wounds in comparison with other synthetic medications in terms of microbial resistance and treatment costs are also described to support its traditional claims.

Treatment of non-healing leg ulcers with honeydew honey

BACKGROUND

Honey is used as a traditional medicine for centuries by different cultures for the treatment of various disorders. However, not all honeys exhibit equal antimicrobial potency and only a few meet the criteria for clinical usage.

AIM

The aim of the study was to determine clinical efficacy of sterilised honeydew honey in the treatment of the lower leg ulcers in 25 patients. Furthermore, we evaluated honey acceptability of patients in terms of pain and overall satisfaction.

METHODOLOGY

A total of 25 patients with chronic venous leg ulcers were recruited into this study. The 100% γ-irradiated sterile honeydew honey was applied onto the cleaned wounds and each wound was assessed at the least two times in for a period of 6 weeks.

RESULTS

During the course of treatment, the average wound area of all patients decreased significantly from 51 (3-150) to 22 (0-91) cm(2). Eighteen patients (72%) experienced a decrease in reported pain levels while five patients (20%) experienced the same level of pain throughout the study. The overall satisfaction with honey treatment was positive in 80% of patients. Only two patients experienced poor tolerance due to problems at ulcer site related to pain.

CONCLUSION

Based on these findings, honeydew honey has the potential to be one of the medical-grade honeys.

Manuka honey-impregnated dressings in the treatment of neuropathic diabetic foot ulcers

In this study, we investigate the effect of manuka honey-impregnated dressings (MHID) on the healing of neuropathic diabetic foot ulcers (NDFU). A total of 63 Caucasians, type 2 diabetic patients followed up in the diabetic foot outpatient clinic comprised the study population. Patients were randomised in two groups as follows: group I patients were treated with MHID and group II patients were treated with conventional dressings (CD). The patients were followed up on a weekly basis for 16 weeks. Mean healing time was 31 ± 4 days in group I versus 43 ± 3 days in group II (P < 0·05). In group I patients 78·13% of ulcers became sterile during the first week versus 35·5% in group II patients; the corresponding percentages for weeks 2, 4 and 6 were 15·62% versus 38·7%, 6·25% versus 12·9% and 0% versus 12·9% respectively. The percent of ulcers healed did not differ significantly between groups (97% for MHID and 90% for CD). MHID represent an effective treatment for NDFU leading to a significant reduction in the time of healing and rapid disinfection of ulcers.

Evaluation of topical tocopherol cream on cutaneous wound healing in streptozotocin-induced diabetic rats

Diabetes is a common cause of delayed wound healing. The aim of the study was to determine the effect of topical administration of tocopherol cream on the wound healing process in diabetic rats. The study was conducted using 18 male Sprague Dawley rats which were divided into three groups: (I) diabetic rats receiving control cream (n = 6), (II) diabetic rats receiving 0.06% tocopherol cream (n = 6), and (III) diabetic rats receiving 0.29% tocopherol cream (n = 6). Four cutaneous wounds were created at the dorsal region of the rats. Wound healing was assessed by total protein content, rate of wound closure estimation, and histological studies on the tenth day after wounding. Tocopherol treatment enhanced the wound healing process by increasing rate of wound closure and total protein content significantly (P < 0.05) compared to the control group. Histological observation also showed better organized epithelium and more collagen fibers in the tocopherol treated groups. Application of tocopherol cream enhances wound healing process in diabetic condition which is known to cause delay in wound healing.

Energy metabolism, proteotoxic stress and age-related dysfunction - protection by carnosine

This review will discuss the relationship between energy metabolism, protein dysfunction and the causation and modulation of age-related proteotoxicity and disease. It is proposed that excessive glycolysis, rather than aerobic (mitochondrial) activity, could be causal to proteotoxic stress and age-related pathology, due to the generation of endogenous glycating metabolites: the deleterious role of methylglyoxal (MG) is emphasized. It is suggested that TOR inhibition, exercise, fasting and increased mitochondrial activity suppress formation of MG (and other deleterious low molecular weight carbonyl compounds) which could control onset and progression of proteostatic dysfunction. Possible mechanisms by which the endogenous dipeptide, carnosine, which, by way of its putative aldehyde-scavenging activity, may control age-related proteotoxicity, cellular dysfunction and pathology, including cancer, are also considered. Whether carnosine could be regarded as a rapamycin mimic is briefly discussed.

Two major medicinal honeys have different mechanisms of bactericidal activity

Honey is increasingly valued for its antibacterial activity, but knowledge regarding the mechanism of action is still incomplete. We assessed the bactericidal activity and mechanism of action of Revamil® source (RS) honey and manuka honey, the sources of two major medical-grade honeys. RS honey killed Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa within 2 hours, whereas manuka honey had such rapid activity only against B. subtilis. After 24 hours of incubation, both honeys killed all tested bacteria, including methicillin-resistant Staphylococcus aureus, but manuka honey retained activity up to higher dilutions than RS honey. Bee defensin-1 and H₂O₂ were the major factors involved in rapid bactericidal activity of RS honey. These factors were absent in manuka honey, but this honey contained 44-fold higher concentrations of methylglyoxal than RS honey. Methylglyoxal was a major bactericidal factor in manuka honey, but after neutralization of this compound manuka honey retained bactericidal activity due to several unknown factors. RS and manuka honey have highly distinct compositions of bactericidal factors, resulting in large differences in bactericidal activity.