Enzyme-Digested Peptides Derived from Lates calcarifer Enhance Wound Healing after Surgical Incision in a Murine Model

Surgical wounds are common injuries of skin and tissues and usually become a clinical problem. Until now, various synthetic and natural peptides have been widely explored as potential drug candidates for wound healing. Inhibition of the TNF-α signaling pathway and promotion of angiogenesis are suggested to be involved in their effects. Angiogenesis at the wound site is one of the essential requisites for rapid healing. In the present study, a novel peptide extract derived from the natural source Lates calcarifer, commonly known as sea bass or barramundi, was evaluated for its wound healing property. The specific acidic and enzymatic approaches were employed for producing sea bass extract containing small size peptides (molecular weight ranging from 1 kD to 5 kD). The cytotoxicity of the extract was examined in HaCaT and NIH3T3. After this, the effects of enzyme digested peptide extracts of sea bass on wound healing in mice were investigated. The peptide extracts (660 and 1320 mg/kg/day) and control protein (1320 mg/kg/day) was orally given to the wounded mice, respectively, for 12 days. The surgical method was improved by implanting a silicone ring at the wound site. The ring avoided the contracting effect in murine wounds, making it more closely related to a clinical condition. The results showed promising improvement at the wound site in mice. Sea bass peptide extracts accelerated the wound healing process and enhanced the microvessel formation at the wound site. The remarkable effects of this novel sea bass peptide extract in healing traumatic injuries revealed a new option for developing wound management.     

Healing potential of mesenchymal stem cells cultured on a collagen-based scaffold for skin regeneration

Background: Wound healing of burned skin remains a major goal in public health. Previous reports showed that the bone marrow stem cells were potent in keratinization and vascularization of full thickness skin wounds. Methods: In this study, mesenchymal stem cells were derived from rat adipose tissues and characterized by flowcytometry. Staining methods were used to evaluate their differentiation ability. A collagen-chitosan scaffold was prepared by freeze-drying method and crosslinked by carbodiimide-based crosslinker. Results: The results of immunecytochemistry and PCR experiments confirmed the adipose-derived stem cells (ASC) in differentiation to the keratinocytes under the treatment of keratinocyte growth factor. The isolated ASC were seeded on the scaffolds and implanted at the prepared wounds. The scaffolds without cells were considered as a control and implanted on the other side of the rat. Histopathological analyses confirmed the formation of new tissue on the scaffold-cell side after 14 days with the formation of dermis and epidermis. Conclusion: These results indicated the capacity of ASC in differentiation to keratinocytes and also wound healing in vivo. Key Words: Tissue engineering, Keratinocytes, Mesenchymal stem cells     

Naringin-loaded Poly(ε-caprolactone)/Gelatin Electrospun Mat as a Potential Wound Dressing: In vitro and In vivo Evaluation

In the present study, naringin, a flavonoid isolated from the grape and citrus fruit species, was incorporated with poly(ε-caprolactone)/gelatin composite mats in order to develop a potential wound dressing. The composite mats were prepared by electrospinning of poly(ε-caprolactone)/gelatin (1:1 (w/w)) solution incorporated with 1.50 %, 3 % and 6 % (w/w) of naringin. The electrospun mats were evaluated regarding their morphology, contact angle, water-uptake capacity, water vapor transmission rate, tensile properties, drug release, cellular response and in vivo wound healing activity. The study showed that after 2 weeks, the full-thickness excisional wounds of Wistar rats treated with the naringin-loaded dressings achieved a wound closure of higher than 94 % and the dressing containing 6 % (w/w) naringin had almost 100 % wound closure. The sterile gauze, as the control group, showed nearly 86 % of wound closure after this period of time. Our results provided evidence that supports the possible applicability of naringin-loaded wound dressing for successful wound treatment.     

Oral administration of skin gelatin isolated from Chum salmon (Oncorhynchus keta) enhances wound healing in diabetic rats

Care for diabetic wounds remains a significant clinical problem. The present study was aimed at investigating the effect of skin gelatin from Chum Salmon on defective wound repair in the skin of diabetic rats. Full-thickness excisional skin wounds were made in 48 rats, of which 32 were diabetes. The diabetic rats were orally treated daily for 14 days with skin gelatin from Chum Salmon (2 g/kg) or its vehicle. Sixteen non-diabetic control rats received the same amount of water as vehicle-treated non-diabetic rats. Rats were killed to assess the rate of wound closure, microvessel density (MVD), vascular endothelial growth factor (VEGF), hydroxyproline (HP) contents in wound tissues and nitrate in plasma and wound tissue at 7 and 14 days after wounding. Skin gelatin-treated diabetic rats showed a better wound closure, increased MVD, VEGF, hydroxyproline and NO contents and a reduced extent of inflammatory response. All parameters were significant (P < 0.05) in comparison to vehicle-treated diabetic group. In light of our finding that skin gelatin of Chum Salmon promotes skin wound repair in diabetic rats, we propose that oral administration of Chum Salmon skin gelatin might be a beneficial method for treating wound disorders associated with diabetes.     

Assessment of dermal wound healing and in vitro antioxidant properties of Avena sativa L.

Avena sativa L. (Poaceae) has been reported to have traditional utilization against skin diseases and inflammation. Therefore, in this study, the n-hexane, ethyl acetate, ethanol, and water extracts of A. sativa were investigated for their wound healing and antioxidant activities. Total phenol and flavonoid contents of the extracts were established spectrophotometrically. For the wound healing activity, linear incision and circular excision models on rats and mice were evaluated with a standard ointment Madecassol^®. Antioxidant activity was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferrous ion-chelating, and ferric-reducing antioxidant power (FRAP) assays. Significant wound healing activity was observed with the ointment formulation of the ethanol extract at 1% concentration. The histopathological examination results also supported the outcome of both linear incision and circular excision wound models. All of the extracts exerted low antioxidant activity in the applied assays. The present study provides a scientific evidence for the traditional usage of A. sativa in the management of wound healing.     

Efficacy of papain-based wound cleanser in promoting wound regeneration

A new invention, papain-based wound cleanser is formulated by incorporating papain, a proteolytic enzyme extracted from Carica papaya into the formulation. This cleanser is invented to simplify the methods in wound management by combining wound cleansing and wound debridement using a single formulation. This study describes the preparation and preclinical study of papain-based wound cleanser in accelerating wound healing. In this study, papain-based wound cleanser was used to treat wound incision on Sprague-Dawley rats while distilled water and Betadine were used as negative and positive control. Twenty-seven clinically healthy white rats were randomly divided into three groups and treated accordingly until the 21st day post-incision. Wound reduction rates and histological analysis were obtained to asses the healing pattern. Rats treated with papain-based wound cleanser showed a progressive wound healing based on the wound reduction rates and histological analysis when compared with rats treated with distilled water and Betadine. Better collagen deposition and presence of skin organelles in rats treated with papain-based wound cleanser demonstrated its efficacy in promoting wound healing. In addition to its wound healing effect, papain-based wound cleanser is also integrated with antibacterial properties which make it a complete package for wound management. However, further studies should be carried out to ensure its safety for human usage.     

Characterization of Isoforms of the Lectin Isolated from the Red Algae Bryothamnion seaforthii and Its Pro-Healing Effect

Lectins are a structurally heterogeneous group of proteins that have specific binding sites for carbohydrates and glycoconjugates. Because of their biotechnological potential, lectins are widely used in biomedical research. The present study aimed to evaluate the healing potential of the lectin isolated from the marine red alga Bryothamnion seaforthii (BSL). The lectin was purified using ion exchange chromatography with DEAE cellulose and characterized using tandem mass spectrometry. For healing tests, skin wounds were induced in the dorsal thoracic region of mice. These animals were randomly divided into three groups and subjected to topical treatment for 12 days with BSL, bovine serum albumin and 150 mM NaCl. To evaluate the potential of each treatment, the animals were anesthetized and sacrificed on days 2, 7 and 12, respectively. The parameters evaluated included the wound area, the proportion of wound closure and the histological diagnosis. The wound closure was more effective with BSL (Postoperative Day 7 and 12) than controls. The luminal epithelium was completely restructured; the presence of collagen in the dermis and the strongly active presence of young skin annexes demonstrate the potential of treatment with BSL compared with controls. Our findings suggest that BSL has pro-healing properties and can be a potential medical process in the treatment of acute wounds.     

The effect of wound severity, type of tissue, and use of the tuber disk model system on arachidonic acid-induced rishitin accumulation in potato tuber

The wound response within damaged potato tubers (Solanum tuberosum L.) must be a coordination of suberization with other resistance responses if infection is to be avoided. Previously, we showed that wound healing was affected by wound severity and consequently the type of tissue damaged within the tuber. Using arachidonic acid-induced accumulation of rishitin as a model for phytoalexin accumulation, we now demonstrate that this tuber resistance response is also influenced by wound severity and the type of tissue exposed to the elicitor. Kennebec and Reddale tubers that were superficially wounded by removing a thin tissue slice (0.75 mm thick) from the surface and then treated with the elicitor arachidonic acid produced significantly less rishitin than more severely wounded tubers (e.g., tubers cut in half) and excised tuber tissue disks (17 mm × 4 mm). Excised, elicitortreated tuber tissues accumulated significantly more rishitin in cortical cells than in perimedullary and pith cells. Rishitin accumulation was routinely measured 96 h after wounding and was found to be declining by 144 h regardless of wound severity. Induction of rishitin accumulation was very localized with more than 80 % of the rishitin found within 0.75 mm of the treated wound. These results indicate that excised tuber tissue disks, often used as models in wound research, are not fully representative of intact tubers. Perhaps more important, the results show that superficial wounds of intact tubers, i.e., similar to shallow nick and abrasion type wounds typically incurred during harvest, accumulate very little rishitin. However, rishitin accumulation in the tuber disk model system is much greater than that found in superficially wounded tubers, but is similar to the accumulation that could be elicited in cut (seed) tubers. The complications contributed by these wound-related and tissue-specific interactions must be factored into the model system(s) used in describing the role(s) of phytoalexins in the broad framework of disease resistance for stored potatoes and cut seed.     

Clinical Trial: Marine Lipid Suppositories as Laxatives

Cod-liver oil and other marine products containing polyunsaturated fatty acids have anti-inflammatory, anti-bacterial and anti-viral effects and may be useful in the treatment of various inflammatory and infectious diseases. We developed suppositories and ointment with 30% free fatty acid (FFA) extract from omega-3 fish oil. Our purpose was to evaluate the safety of marine lipid suppositories and ointment in healthy volunteers and to explore the laxative effect of the suppositories. Thirty healthy volunteers were randomized either to a study group administrating 30% FFA suppositories and applying 30% FFA ointment to the perianal region twice per day for two weeks, or to a control group using placebo suppositories and ointment in a double blinded manner. Results: No serious toxic effects or irritation were observed. In the study group 93% felt the urge to defecate after administration of the suppositories as compared to 37% in the control group (P = 0.001). Subsequently 90% in the study group defecated, compared to 33% in the control group (P = 0.001). Conclusion: The marine lipid suppositories and ointment were well tolerated with no significant toxic side effects observed during the study period. The suppositories have a distinct laxative effect and we aim to explore this effect in further clinical trials.     

Comparison of topical triamcinolone and oral atorvastatin in treatment of paederus dermatitis Northern Iran

Dermatitis caused by stimulation of beetle paederus, is a common health problem in Northern and some southern parts of Iran. Since by now, traditional medicine and some corticosteroid agents have been used for treatment of dermatitis caused by beetle paederus. Because, there are few researches about classical treatment of the disease at academic level, this study planned to compare the effectiveness of triamcinolone ointment and atorvastatin tablet with placebo in treatment ofpaederus dermatitis in Northern Iran. A randomized double-blind clinical trial was carried out on 30 patients referred to the hospital and clinics at Sari and Neka countries in Northern Iran during 6 months. Patients were randomly divided into two therapeutic equal groups. The first group was triamcinolone ointment twice a day and a placebo atorvastatin tablet daily. The second group was oral atorvastatin one tablet (20 mg) daily and a placebo triamcinolone ointment twice a day. In Seventh day of visits, therapeutic response of the patients in triamcinolone and atorvastatin group were 93.33 and 80%, respectively. No significant differences were found in therapeutic outcome between the two groups (p > 0.05). The results showed both oftriamcinolone ointment and oral atorvastatin had similar effect on paederus dermatitis. Because the paederus dermatitis is a self-limited disease use of topical therapy for treatment of the disease is recommend.     

An Electrospun Scaffold Loaded with an Enteromorpha Polysaccharide for Accelerated Wound Healing in Diabetic Mice

The design and development of innovative multifunctional wound dressing materials in engineered biomaterials is essential for promoting tissue repair. In this study, nanofibrous wound dressing materials loaded with anti-inflammatory ingredients were manufactured by a promising electrospinning strategy, and their capability for treating diabetic wounds was also investigated. A scaffold blend consisting of an Enteromorpha polysaccharide and polyvinyl alcohol (PVA) was fabricated. The in vitro and in vivo studies confirmed the efficacy of PVA/EPP1 fiber. We found that PVA/EPP1 fiber accelerated the repair of a full-thickness skin wound in diabetic mice. The results suggest that this scaffold could effectively shorten the wound healing time by inhibiting inflammatory activity, which makes it a promising candidate for the treatment of hard-to-heal wounds caused by diabetes.     

Antibacterial Bilayered Skin Patches Made of HPMA and Quaternary Poly(4-vinyl pyridine)

This study aimed to produce poly(4-vinyl pyridine) and hydroxypropyl methacrylamide (HPMA)-based bilayer wound dressings materials enhancing healing mechanism for the wounds which have self-healing problem and high infection risk. These materials were designed to protect wound from secondary traumas caused microorganism invasion and do not have toxic substance release problem. Synthesis of quaternary poly(4-vinyl pyridine) (poly(Q4-VP)) which is the antibacterial layer of wound dressing material was carried out in two stages. At first stage, poly(4-vinyl pyridine) polymer was synthesized from 4-vinyl pyridine monomer by free radical polymerization. Then, poly(Q4-VP) was synthesized from poly(4-VP) by alkylation reaction with 6-bromocaproic acid. Resulted polymer was structurally characterized by FT-IR. The macroporous spongy structure, as the lower layer of wound dressing material, was prepared by cryogelation of HPMA. Then, the antibacterial polymer was electrospun onto the cryogel structure and bilayered material was obtained. Cryogel structure, fiber morphology and layer integration was examined by SEM. In order to enhance wound healing process, ascorbic acid (vitamin C) was loaded to cryogel layer and release was followed by spectrophotometrically. The antimicrobial properties of the materials were examined against Escherichia coli, Staphylococcus aureus and Candida albicans, respectively. According to the results, bilayered, antibacterial and antifungal against Staphylococcus aureus and Candida albicans, temporary wound dressings which can stimulate wound healing and have high swelling capacity were obtained successfully.     

Wound healing,decay and chemical treatment of cut potato tuber tissue

Potato tuber tissue inoculated at cutting withFusarium spp. orErwinia carotovora and exposed to conditions favorable for infection did not heal rapidly enough to prevent decay. Seven days of wound healing at 20 C and high relative humidity prior to inoculation were necessary to provide protection againstFusarium and two days were required to protect againstErwinia. Histological examination of cut and chemically treated tuber tissue revealed that the wound healing process was only minimally affected by mancozeb, zineb-streptomycin, zineb-fir bark, captan, captan-mertect, captan-fir bark, and sodium hypochlorite. Ethylmercury p-toluene-sulfonanalide and pyrrolidine induced formation of discontinuous wound periderm after 21 days of healing. Streptomycin and captan-rhodamine had very detrimental effects on wound healing and suberin formation. In general, the seed-piece treatment chemicals tested had only minor effects on normal wound healing. It is concluded that wound healing alone may not be sufficient to controlFusarium caused seed piece decay and chemical treatment is recommended to provide protection until wound healing can occur. At least two days of wound healing are required for control of decay caused byErwinia carotovora.     

A Marine-Derived Anti-Inflammatory Scaffold for Accelerating Skin Repair in Diabetic Mice

Reconstructing the typical analogue of extracellular matrix (ECM) in engineered biomaterials is essential for promoting tissue repair. Here, we report an ECM-mimetic scaffold that successfully accelerated wound healing through enhancing vascularization and regulating inflammation. We prepared an electrospun fiber comprising a brown alga-derived polysaccharide (BAP) and polyvinyl alcohol (PVA). The two polymers in concert exerted the function upon the application of PVA/BAP2 fiber in vivo; it started to reduce the inflammation and promote angiogenesis at the wound site. Our serial in vitro and in vivo tests validated the efficacy of PVA/BAP2 fiber. Particularly, PVA/BAP2 fiber accelerated the repair of a full-thickness skin wound in diabetic mice and induced optimal neo-tissue formation. Generally, our results suggest that, by mimicking the function of ECM, this fiber as an engineered biomaterial can effectively promote the healing efficiency of diabetic wounds. Our investigation may inspire the development of new, effective, and safer marine-derived scaffold for tissue regeneration.     

Porometric measurements indicate wound severity and tuber maturity affect the early stages of wound-healing

We demonstrated that porometrically derived wound-healing profiles of whole tubers were greatly affected by the depth or severity of the wound. A rapid decrease in water vapor conductance was detected during the first 24 h of healing after mature, whole tubers were wounded by tangentially cutting into the cortex. The rapid decline in vapor conductance, indicating deposition of soluble waxes, was not concurrent with detectable deposition of polymeric phenolic or polymeric aliphatic components of the suberin polyester; instead these polymerized components were detected after vapor conductance decreased by approximately 80% and was nearly stable. The rate of decline of vapor conductance of wound-healing tubers was hormonally hastened with abscisic acid treatments. Although deeper tangential wounds (3.0 mm) had slower initial rates of wound-healing than did shallow wounds (0.75 mm) through tuber growth and maturation, the ability to wound-heal more rapidly increased as the tubers matured in the field. The vapor conductance of wound healing tubers declined in a log-linear fashion during the first 1 to 3 days after wounding depending upon tuber maturity and genotype.     

Investigations on the Wound Healing Potential of Tilapia Piscidin (TP)2-5 and TP2-6

Wound healing is a highly orchestrated process involving many cell types, such as keratinocytes, fibroblasts and endothelial cells. This study aimed to evaluate the potential application of synthetic peptides derived from tilapia piscidin (TP)2, TP2-5 and TP2-6 in skin wound healing. The treatment of HaCaT keratinocytes with TP2-5 and TP2-6 did not cause cytotoxicity, but did enhance cell proliferation and migration, which could be attributed to the activation of epidermal growth factor receptor signaling. In CCD-966SK fibroblasts, although TP2-5 (31.25 μg/mL) and TP2-6 (125 μg/mL) showed cytotoxic effects, we observed the significant promotion of cell proliferation and migration at low concentrations. In addition, collagen I, collagen III, and keratinocyte growth factor were upregulated by the peptides. We further found that TP2-5 and TP2-6 showed pro-angiogenic properties, including the enhancement of human umbilical vein endothelial cell (HUVEC) migration and the promotion of neovascularization. In a murine model, wounds treated topically with TP2-5 and TP2-6 were reduced by day 2 post-injury and healed significantly faster than untreated wounds. Taken together, these findings demonstrate that both TP2-5 and TP2-6 have multifaceted effects when used as topical agents for accelerating wound healing.     

Comparison of Assimilation Rates in Leaves at Various Nodes in Canopies of Three Spring Wheat Cultivars with Different Plant Forms

Abstract

This study was conducted to reveal the ideotype of wheat (Triticum aestivum L.) canopy structure for high yield and biornass productivity. The assimilation rate and nitrogen contents of the flag, second, third and lower leaves and the ear of the main stem were measured in three spring cultivars with different plant forms (figures), Haruyutaka, Norin 61 and Selpek, under field conditions. The assimilation rate was evaluated based on the amount of water-soluble carbohydrate accumulated during the day (WSC/day). Surface area indexes of the ear and flag leaf in Haruyutaka and Selpek were larger than those in Norin 61. In Haruyutaka and Selpek, the amount of WSC/day was larger in the flag leaf than in the second or third leaf, which had a sufficiently high nitrogen content. On the contrary, in Norin 61, the amount of WSC/day in the flag leaf was similar to that in the second and third leaves during the grain-filling period. The amount of WSC/day in the flag leaf during the last half of the grain-filling period was much higher in Selpek than in Haruyutaka and Norin 61. This may be one of the reasons why Selpek had a heavier total dry weight than Haruyutaka and Norin 61 in 1993 and 1995.     

Fabrication of electropsun PLGA and small intestine submucosa-blended nanofibrous membranes and their biocompatibility for wound healing

In recent decades, tremendous research has focused on the production of nanoscale fibers using synthetic polymers, with the goal of fabricating nanofibrous scaffolds for wound healing. However, the hydrophobicity of such polymers typically hinders attachment and proliferation of the cells. In this study, we combined poly-d,l-lactide-co-glycolide (PLGA) and small intestine submucosa (SIS) to fabricate blended nanofibers for wound healing by electrospinning. PLGA and SIS were dissolved in 1,1,1,3,3,3-hexafluoro isopropanol to produce different weight ratios of PLGA/SIS-blended nanofibrous membranes (NFM). Physicochemical characterization of the electrospun NFM was performed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, water contact angle analysis, degradation test and tensile testing. The PLGA/SIS-blended NFM showed improved hydrophilicity and tensile strength. Better infiltration, attachment and proliferation of rat granulation fibroblasts of PLGA/SIS-blended NFMs compared to PLGA NFMs were identified by morphological differences determined by SEM and a water-soluble tetrazolium salt assay kit. Based on our results, the PLGA/SIS blended NFMs were found to be suitable for use as a potential material for wound dressing.     

The effects of dihydroquercetin on the cut surface of seed potatoes

The purpose of this study was to determine the effects which dihydroquercetin (DHQ) has on the natural healing process of suberization and wound periderm initiation in cut seed potatoes. Dihydroquercetin is a phenolic compound extracted from the bark of Douglas Fir,Pseudotsuga menziesii (Mirb.) Franco. Anatomical studies of treated seed potato tissue showed that treatment with bark-383, the cork-rich fraction of the whole bark containing approximately 2% pure DHQ, increases the thickness of the suberized layer formed below the cut surface. Treatment with 4% bark fraction I, which is blended to that concentration with the inert carrier dust Pyrax and contains approximately the same amount of DHQ as does the bark-383, also promoted the formation of a thicker layer of suberized cells. The thickness of the wound periderm did not significantly vary as a result of the use of any treatments containing DHQ. The use of Captan (Orthocide 50W) as a cut seed treatment in these studies was found to inhibit the formation of a suberized layer and subsequently the initiation of a wound periderm. The combination of bark-383 and Orthocide 50W in a treatment mixture reversed the inhibitory affect of the Orthocide 50W alone and therefore allowed for the formation of a well suberized layer and a wound periderm. It was found that wound healing on the cut surface of seed potatoes is largely dependent on the type of tissue present at any given point on that cut surface. Therefore, the response to treatment of the stolon end, center, and blossom end tissues was related to the type of tissue which was present in each of those tuber regions. The fungal mold growth on treated seed pieces incubated in a controlled environment was adequately retarded when Orthocide 50W was combined with bark-383 in a mixture ratio of 1:9 respectively. The longer the treatment material was allowed to remain on the seed piece, the greater was the protection against mold growth afforded by the mixture.     

SPI/PEO blended electrospun martrix for wound healing

Conventional textile based wound dressing materials are cost effective and highly absorbent, but when used alone fails to provide optimal wound healing conditions like homeostasis, non-adherence, maintenance of a moist wound bed, etc. Electrospun polymer web meets the requirements outlined for wound healing, by their microfibrous structures provide suitable environment for wound healing apart from the function of polymers. In this study, blends of soy protein isolate (SPI) and poly(ethylene oxide) (PEO) nano fiber web was prepared by electro spinning process. The developed blended nano fiber web was subjected to SEM, FTIR to evaluate fiber size and functional properties respectively. The Moisture vapour transmission rate (MVTR) result shows the blended electrospun web gives suitable mosit environment over wound bed such as the MVTR is 2994 g/m²/day. The blended electrospun web gives positive result on antimicrobial activity. The effect of SPI/PEO blended electrospun web on wound healing was experimented with female wistar rats and the blended electrospun web shows excellent result on wound healing by the growth of new epithelium without any significant adverse reaction. Forming of SPI/PEO electrospun fiber was fulfilled many critical elements desirable in a wound material.