Serine protease activity in blood plasma during the healing of aseptic and infected wounds under experimental conditions

Activity of serine proteases--kallikrein-like activity (KLA) and plasmin-like activity (PLA)--were studied in the blood plasma of 220 sexually mature male Wistar rats with simulated aseptic and infected surface wounds in the time course before the operation, daily from the 1st to 10th day, as well as 12 and 15 days after the surgery. During the healing of aseptic and especially infected wound blood plasma KLA and PLA were found to be decreasing, thus indicating the active role of factor-XII-dependent systems in wound healing, reflecting the response of the body to operation-induced injury and wound infection, and dependent on the character and stage of wound healing course.     

负压封闭引流技术治疗剖宫产术后切口愈合不良41例的分析

目的：探讨负压封闭引流技术在剖宫产术后切口愈合不良中的应用及疗效。方法：剖宫产术后切口愈合不良41例,其中脂肪液化35例,切口感染7例,应用负压封闭引流装置治疗3～7天后再行局部换药或二次手术缝合。结果：负压封闭引流治疗时间平均为4．15＋1．24天,之后采取换药治疗者15例,平均愈合时间14．6±3136天;采取二次手术缝合者26例,伤口均一期愈合。结论：负压封闭引流治疗剖宫产术后切口愈合不良,可明显促进肉芽组织生长,缩短创面愈合时间,同时为二次手术缝合创造条件。     

Exogenous Tryptophan Promotes Cutaneous Wound Healing of Chronically Stressed Mice through Inhibition of TNF-α and IDO Activation

Stress prolongs the inflammatory response compromising the dermal reconstruction and wound closure. Acute stress-induced inflammation increases indoleamine 2, 3-dioxygenase-stimulated tryptophan catabolism. To investigate the role of indoleamine 2, 3-dioxygenase expression and tryptophan administration in adverse effects of stress on cutaneous wound healing, mice were submitted to chronic restraint stress and treated with tryptophan daily until euthanasia. Excisional lesions were created on each mouse and 5 or 7 days later, the lesions were analyzed. In addition, murine skin fibroblasts were exposed to elevated epinephrine levels plus tryptophan, and fibroblast activity was evaluated. Tryptophan administration reversed the reduction of the plasma tryptophan levels and the increase in the plasma normetanephrine levels induced by stress 5 and 7 days after wounding. Five days after wounding, stress-induced increase in the protein levels of tumor necrosis factor-α and indoleamine 2, 3-dioxygenase, and this was inhibited by tryptophan. Stress-induced increase in the lipid peroxidation and the amount of the neutrophils, macrophages and T cells number was reversed by tryptophan 5 days after wounding. Tryptophan administration inhibited the reduction of myofibroblast density, collagen deposition, re-epithelialization and wound contraction induced by stress 5 days after wounding. In dermal fibroblast culture, the tryptophan administration increased the cell migration and AKT phosphorylation in cells treated with high epinephrine levels. In conclusion, tryptophan-induced reduction of inflammatory response and indoleamine 2, 3-dioxygenase expression may have accelerated cutaneous wound healing of chronically stressed mice.     

Alcohol extract of Echinacea pallida reverses stress-delayed wound healing in mice

Healing of open skin wounds begins with an inflammatory response. Restraint stress has been well documented to delay wound closure, partially via glucocorticoid (GC)-mediated immunosuppression of inflammation. Echinacea, a popular herbal immunomodulator, is purported to be beneficial for wound healing. To test the hypothesis, an alcohol extract of E. pallida was administrated orally to mice for 3 days prior to, and 4 days post wounding with a dermal biopsy on the dorsum. Concominantly, mice were exposed to 3 cycles of daily restraint stress prior to, and 4 cycles post wounding. Echinacea accelerated wound closure in the stressed mice, but had no apparent wound healing effect for the non-stressed mice when compared to their respective controls. To test if the positive healing effect is through modulation of GC release, plasma corticosterone concentrations were measured in unwounded mice treated with restraint stress and the herbal extract for 4 days. Plasma GC in restraint stressed mice gavaged with Echinacea was not different from mice treated with restraint only, but was increased compared to the vehicle control. This data suggests that the improved wound healing effect of Echinacea in stressed mice is not mediated through modulation of GC signaling.     

Ultrastructural analysis between fetal and adult wound healing process of marsupial opossum skin

The opossum delivers a newborn baby equivalent to tremature fetus state by postpregnancy. The peculiarity is advantageous for studies of fetus, because operations to take out fetus from the uterus of a mother are not necessary. When mammalian skin is wounded by full-thickness excision, fetal and adult wound healing processes differ. Fetal-type wound healing does not leave a scar. However, studies of how the fetal wound healing process differs in detail from the adult type are not advanced. We first observed the normal skin development of the gray short-tailed opossum (Monodelphis domestica) using an electron microscope. As for normal skin, an epidermis became multi-layered, and thickened from birth through to 7 days after birth. The quantity of extracellular matrix of the dermis increased thereafter, and several types of cells were found in the dermis. To examine the wound healing, we used material from a 1 day-old newborn baby, and from another 15 days after birth, and compared the wound healing style morphologically. Differences in the constitution of cells and fine structures of the skin were observed, it was obviously suggested that change in the wound healing style from fetal-type to adult-type occurred between 1 to 15 days after birth.     

封闭负压引流对兔糖尿病溃疡创面组织愈合影响的观察

目的:探讨封闭负压引流(VAC)对兔糖尿病溃疡创面组织愈合的影响及其可能机制。方法:采用四氧嘧啶法建立兔糖尿病溃疡模型,设空白对照组和实验组(对照组创面采用常规包扎治疗处理,实验组创面则采用VAC处理),观察和比较两组动物的创面肉眼观、愈合时间,在致伤前、致伤后3 d、7 d、14 d取创面软组织,检测和比较两组动物的创面组织含水量、血流量以及血浆ET-1和NO含量。结果:与对照组比较,实验组动物的创面肿胀及分泌物得到明显控制,创面坏死组织的清除与肉芽组织的生长明显加快,平均愈合时间明显缩短(P0.05);致伤后3 d、7 d和14 d,创面组织含水量与血浆ET-1含量明显下降(P0.05),创面组织血流量与血浆NO含量明显增加(P0.05)。结论:VAC对兔糖尿病溃疡创面组织的愈合可起到积极的促进作用,这可能与其增加血浆NO含量及降低ET-1的含量有关,其具体机制尚有待于进一步的研究。     

Wound healing and regeneration in the imaginal wing disc ofDrosophila

Summary When complementary fragments of an imaginal disc ofDrosophila are cultured for several days prior to metamorphosis, usually one fragment will regenerate while the other will duplicate. It has been proposed that wound healing plays an important part in disc regulation (French et al. 1976; Reinhardt et al. 1977) by initiating cell proliferation and determining the mode of regulation. We tried to delay the wound healing process by leaving a region of dead cells between the wound edges. In 06 fragments (Bryant 1975a) wound healing has occurred after 1–2 days of culture and the regeneration of missing structures after 2–4 days of culture. We observed that leaving a region of dead cells between the wound edges delays both wound healing and the regeneration of missing structures by 2 days.When disc fragments are cultured in female abdomens and then exposed to³H-thymidine to label replicating cells, then the label is found to be localised around the wound. We observed that delaying wound healing does not delay this localisation of labelled nuclei indicating that wound healing may not be required to initiate DNA replication.     

Impaired cutaneous wound healing after sensory denervation in developing rats: effects on cell proliferation and apoptosis

The role of sensory nociceptor nerves in cutaneous wound healing was investigated following full-thickness 4-mm diameter dorsal cutaneous excision wounding of rats on postnatal day 12. In rats with intact innervation, wounds at 3 days contained large numbers of TUNEL- and BRDU-labeled nuclei, consistent with inflammatory cell death and granulation cell proliferation. Wound area and volume decreased through 11 days in concert with a transient appearance of alpha-smooth muscle actin-immunoreactive myofibroblasts, declining rates of cell division, and increased occurrence of apoptotic cells. Sensory denervation by capsaicin injections on postnatal days 2 and 9 reduced calcitonin gene-related peptide-immunoreactive wound innervation persistently by up to 43%. This was associated with increased wound surface area and volume, and delays in scab loss and re-epithelialization. Relative to control wounds, granulation tissue showed increased myofibroblast content at 5-7 days. Capsaicin-treated rats had more BRDU-labeled cells, including myofibroblasts, through day 7. Numbers of TUNEL apoptotic cells per unit area of tissue section were reduced by denervation in both early and late stages of healing. We conclude that partial loss of sensory innervation impairs cutaneous wound healing in developing rats, as manifested by delayed re-epithelialization and failure of the wound area to decrease normally through at least 21 days. This is associated with an abnormally enlarged wound tissue volume resulting from increased granulation cell proliferation without proportionate increases in apoptosis. These findings suggest that nociceptor innervation plays a critical role in wound healing by regulating wound cellularity.     

Plasma treatments of dressings for wound healing: a review

This review covers the use of plasma technology relevant to the preparation of dressings for wound healing. The current state of knowledge of plasma treatments that have potential to provide enhanced functional surfaces for rapid and effective healing is summarized. Dressings that are specialized to the needs of individual cases of chronic wounds such as diabetic ulcers are a special focus. A summary of the biology of wound healing and a discussion of the various types of plasmas that are suitable for the customizing of wound dressings are given. Plasma treatment allows the surface energy and air permeability of the dressing to be controlled, to ensure optimum interaction with the wound. Plasmas also provide control over the surface chemistry and in cases where the plasma creates energetic ion bombardment, activation with long-lived radicals that can bind therapeutic molecules covalently to the surface of the dressing. Therapeutic innovations enabled by plasma treatment include the attachment of microRNA or antimicrobial peptides. Bioactive molecules that promote subsequent cell adhesion and proliferation can also be bound, leading to the recruitment of cells to the dressing that may be stem cells or patient-derived cells. The presence of a communicating cell population expressing factors promotes healing.     

The effects of topical treatment with acidified nitrite on wound healing in normal and diabetic mice

The effects of the application of a nitric oxide generating acidified nitrite cream comprising sodium nitrite and citric acid, on the healing of incisional wounds in mice, has been investigated. The effects of acidified nitrite on wound healing were critically dependent on the time of application after wounding. Application of acidified nitrite starting on the day of wounding and on consecutive days thereafter significantly inhibited both half time to closure and extent of wound closure. Conversely, application starting on days 1-4 after wounding and on consecutive days thereafter significantly augmented the rate and extent of wound healing. Optimal effects on improving wound healing were observed with cream concentrations of 3.0% (w/v) sodium nitrite and 4.5% (w/v) citric acid. Starting application on day 5 after wounding had no effect on the rate or extent of wound healing. In diabetic Lepr db/db mice, starting treatment at day 2 after wounding, acidified nitrite at 3.0% (w/v) sodium nitrite and 4.5% (w/v) citric acid significantly increased the rate and extent of wound healing. This suggests that acidified nitrite is effective in improving wound healing against a diabetic background. The present data shows that acidified nitrite cream, a clinically effective means of topically delivering nitric oxide, augments the wound healing process and may be of clinical benefit.     

Promotion of wound healing by yeast glucan evaluated on single animals

The effectiveness of yeast glucan in the acceleration of wound healing was evaluated in mice, rats and guinea pigs. In all experiments comparison between glucan treatment in one hind leg and saline treatment as control on the other leg was made on identical wounds. The degree of healing in the two legs was evaluated macroscopically and classified as follows: 1. healing more advanced in glucan treated wound marked by (+). 2. No significant difference between the two legs marked by (0). 3. Healing more advanced in the control wound, marked by (-). During the days when the differences were most obvious, 60% to 80% of the animals showed more advanced healing in the glucan treated wound, 20% to 40% showed no significant difference; and 0 to 15% showed more advanced healing in the control, saline treated wound. The average time for complete wound healing was reduced by about 18% as a result of glucan treatment. The histological analysis shows that the acceleration of wound healing was mediated by early arrival of macrophages to the wound area in the glucan treated wounds.     

Non-adenine based purines accelerate wound healing

Wound healing is a complex sequence of cellular and molecular processes that involves multiple cell types and biochemical mediators. Several growth factors have been identified that regulate tissue repair, including the neurotrophin nerve growth factor (NGF). As non-adenine based purines (NABPs) are known to promote cell proliferation and the release of growth factors, we investigated whether NABPs had an effect on wound healing. Full-thickness, excisional wound healing in healthy BALB/c mice was significantly accelerated by daily topical application of NABPs such as guanosine (50% closure by days 2.5–2.8). Co-treatment of wounds with guanosine plus anti-NGF reversed the guanosine-promoted acceleration of wound healing, indicating that this effect of guanosine is mediated, at least in part, by NGF. Selective inhibitors of the NGF-inducible serine/threonine protein kinase (protein kinase N), such as 6-methylmercaptopurine riboside abolished the acceleration of wound healing caused by guanosine, confirming that activation of this enzyme is required for this effect of guanosine. Treatment of genetically diabetic BKS.Cg-m+/+lepr db mice, which display impaired wound healing, with guanosine led to accelerated healing of skin wounds (25% closure by days 2.8–3.0). These results provide further confirmation that the NABP-mediated acceleration of cutaneous wound healing is mediated via an NGF-dependent mechanism. Thus, NABPs may offer an alternative and viable approach for the treatment of wounds in a clinical setting.     

Cutaneous wound healing in the sea cucumber, Thyone briareus

Wound healing in the integument of the sea cucumber, Thyone briareus, was studied for up to 50 days after inflicting wide excisional wounds and for 14 days after producing incisional wounds. Rapid re-epithelialization of the wound was effected by the migration of epidermal cells and pigment cells from the periphery of the wound margin. This occurred without apparent evidence of concomitant mitotic activity. Dermal wound healing was completed by the fourteenth day in the incision wounds but occurred very slowly in the broad excision wounds. Morula cells seem to be involved in both epidermal and dermal wound healing, although their precise role is unknown. In excisional wounds the integument was never completely restored to its normal appearance during 50 days of observation.     

Assay of radiation effects in mouse skin as expressed in wound healing

The effect of 150 kVp X irradiation on the healing of full depth surgical wounds in the lower dorsal skin of the mouse was assayed by measuring the wound strength of seven 2-mm-wide segments along each wound. The strength of unirradiated wounds increased with time in two phases: during the first 2 weeks it reached nearly half of the values recorded from unwounded skin, after which the rate of increase slowed for at least 2 weeks before beginning a second increase. By 150 days, the breaking strength of the wound was about 80% of that of unwounded skin. A single dose of 18 Gy prior to wounding reduced the strength of the wounds to about one-third to one-half that of an unirradiated wounds within the 3 months of follow-up. The effect of irradiation on wound strength did not change as the interval between exposure and wounding was increased to 2 months but decreased slightly when this interval was extended to 3 months. When the healing wound was irradiated within 5 days of surgery, the effect on healing was about the same as with preirradiation; if irradiation was delayed for 12 days after wounding the second phase of healing was only postponed and the wound strength ultimately approached the values recorded from unirradiated wounds. The wound strength of skin preirradiated by X rays and assayed 14 days after wounding showed a clear sigmoid dose response with a threshold between 8 and 10 Gy and a plateau at the maximum effect above 20 Gy. The persistence for at least 3 months of the effect of radiation on wound healing suggests that the tissues involved in the healing process are normally proliferating slowly. The accelerated expression of radiation injury through surgical wounding permits the early quantification of the radiation response of tissues that would normally be delayed in their expression of radiation damage.     

Effect of parotid submandibular and sublingual saliva on wound healing in rats.

1. The effectiveness of wound licking with parotid, submandibular or sublingual saliva on wound healing was evaluated in selectively sialadenectomized rats. 2. The rate of healing of experimentally induced cutaneous wounds was evaluated macroscopically by photography at 0, 2, 4 and 6 days after surgery. 3. Sialadenectomy of all major glands significantly slowed down wound healing compared to sham-operated controls. 4. Parotid licking had no effect compared to controls; submandibular licking and sublingual licking appeared to be very effective. 5. The results suggest that saliva promotes wound healing in experimentally induced cutaneous wounds by communal licking; this is a result of the submandibular and sublingual saliva and not the parotid saliva.     

Functional overlap between two classes of matrix-degrading proteases in wound healing.

Retarded wound healing was found in mice deficient in the serine protease precursor plasminogen, as well as in wild-type mice treated with the metalloprotease inhibitor galardin, but in both cases wound closure was ultimately completed in all mice within 60 days. The expression of several matrix metalloproteases in keratinocytes migrating to cover the wound was strongly enhanced by galardin treatment. However, when plasminogen-deficient mice were treated with galardin, healing was completely arrested and wound closure was not seen during an observation period of 100 days, demonstrating that protease activity is essential for skin wound healing. The requirement for both plasminogen deficiency and metalloprotease inhibition for complete inhibition of the healing process indicates that there is a functional overlap between the two classes of matrix-degrading proteases, probably in the dissection of the fibrin-rich provisional matrix by migrating keratinocytes. Each class alone is capable of maintaining sufficient keratinocyte migration to regenerate the epidermal surface, although this function would normally be performed by both classes acting in parallel. Since there are strong similarities between the proteolytic mechanisms in wound healing and cancer invasion, these results predict that complete arrest of this latter process in therapeutic settings will require the use of inhibitors of both classes of proteases.     

Autophagy–mediated plasma membrane removal promotes the formation of epithelial syncytia

Epithelial wound healing in Drosophila involves the formation of multinucleate cells surrounding the wound. We show that autophagy, a cellular degradation process often deployed in stress responses, is required for the formation of a multinucleated syncytium during wound healing, and that autophagosomes that appear near the wound edge acquire plasma membrane markers. In addition, uncontrolled autophagy in the unwounded epidermis leads to the degradation of endo‐membranes and the lateral plasma membrane, while apical and basal membranes and epithelial barrier function remain intact. Proper functioning of TORC1 is needed to prevent destruction of the larval epidermis by autophagy, in a process that depends on phagophore initiation and expansion but does not require autophagosomes fusion with lysosomes. Autophagy induction can also affect other sub‐cellular membranes, as shown by its suppression of experimentally induced laminopathy‐like nuclear defects. Our findings reveal a function for TORC1‐mediated regulation of autophagy in maintaining membrane integrity and homeostasis in the epidermis and during wound healing.     

新型氨基酸制剂对创伤大鼠血游离氨基酸的影响

观察了富含牛磺酸 (Tau)、谷氨酰胺 (Gln)以及高支链氨基酸 (HBCAA)的新型氨基酸制剂对创伤大鼠血中游离氨基酸浓度的影响。结果表明 ,创伤后三天起 ,血浆游离氨基酸总和均显著降低 ,对照组基本无改变 ;创伤后Tau、BCAA、精氨酸以及天冬氨酸等具有抗氧化和免疫调节作用的氨基酸含量明显降低 ,新处方使用一周后其浓度有效回升 ,且效果好于 17种氨基酸 ,从而有利于机体伤口的愈合。这些结果为进一步阐明复合氨基酸制剂促进创伤愈合的作用及其开发应用提供了理论依据     

PDGF在大鼠断层供皮区创面愈合过程中表达变化的研究

实验研究已经证明Ｐｌａｔｅｌｅｔ－ｄｅｒｉｖｅｄｇｒｏｗｔｈｆａｃｔｏｒ（ＰＤＧＦ）能够促进各种类型的伤口愈合,然而在伤口愈合过程中内源性ＰＤＧＦ表达变化的研究却少有报道,为探讨ＰＤＧＦ对伤口愈合的影响,我们应用原位杂交、斑点杂交技术观察了内源性ＰＤＧＦ在大鼠创面愈合过程中的表达变化,结果发现：在创面愈合过程中,肉芽组织中的成纤维细胞,毛细血管内皮细胞及创缘真皮内的毛囊上皮细胞均能表达ＰＤＧＦ－ＢＢ基因,在伤后６天,组织修复的高峰期,ＰＤＧＦ－ＢＢ基因表达达到最强,伤后１２天,伤口完全上皮化,ＰＤＧＦ的基因表达也恢复正常,说明ＰＤＧＦ的基因表达和伤口愈合时间有密切的关系。提示ＰＤＧＦ在创面愈合过程中可能起着重要的调控作用。     

Effects of Foeniculum vulgare essential oil compounds,fenchone and limonene,on experimental wound healing

We investigated the wound healing efficacy of the Foeniculum vulgare compounds, fenchone and limonene, using an excisional cutaneous wound model in rats. An excision wound was made on the back of the rat and fenchone and limonene were applied topically to the wounds once daily, separately or together, for 10 days. Tissue sections from the wounds were evaluated for histopathology. The healing potential was assessed by comparison to an untreated control group and an olive oil treated sham group. We scored wound healing based on epidermal regeneration, granulation tissue thickness and angiogenesis. After day 6, wound contraction with limonene was significantly better than for the control group. Ten days after treatment, a significant increase was observed in wound contraction and re-epithelialization in both fenchone and limonene oil treated groups compared to the sham group. Groups treated with fenchone and with fenchone + limonene scored significantly higher than the control group, but the difference was not statistically significant compared to the olive oil treated group. Our findings support the beneficial effects of fenchone and limonene for augmenting wound healing. The anti-inflammatory and antimicrobial activities of fenchone and limonene oil increased collagen synthesis and decreased the number of inflammatory cells during wound healing and may be useful for treating skin wounds.