Trauma does not aggravate deleterious effects of ischemia reperfusion injury on the lung

OBJECTIVES

Our purpose was to investigate the effects of ischemia-reperfusion injury on traumatized lungs.

MATERIALS AND METHODS

Twenty-four Wistar rats were used in the study. Rats were randomly divided into 4 groups. In the control group (group 1), only anesthesia and ventilation were used. In group 2, only lung ischemia-reperfusion injury was instituted. In group 3, only blunt chest trauma was instituted. And in group 4, lung ischemia reperfusion injury, consisting of 24 hours after the constitution of blunt chest trauma, was used. Lung damage and systemic inflammation parameters were evaluated.

RESULTS

All parameters (alveolar degeneration grades, alveolar macrophage and lymphocyte counts, antioxidant enzyme activities, cytokine levels, and bronchoalveolar lavage fluid albumin level) were higher in all groups than they were in the control group (P < .05). Only tissue malondialdehyde, tissue interleukin-8, and serum glutathione peroxidase levels were significantly higher in the lung ischemia-reperfusion group than they were in the trauma group (P < .05). The trauma + ischemia reperfusion group showed no significant difference when compared with the only ischemia-reperfusion or only trauma groups in any parameters (P > .05).

CONCLUSIONS

The findings showed that lung trauma does not aggravate the deleterious effects of lung ischemia-reperfusion injury.

[Effect of the photosensitizers pheophorbid a and protoporphyrin IX on skin wound healing by the action of low-intensity laser irradiation]

The effect of photosensitizer with subsequent He-Ne (632.8 nm; 3 mW/cm2) laser irradiation on experimental skin wound healing has been studied. Pheophorbid a and protoporphyrin IX were used as photosensitizers. It was found that the application of the photosensitizer and subsequent laser irradiation, first, decreased the amount and the functional activity of leukocyte in wound excudate and, second, inhibited the SOD-activity, compared to that of the control group. Moreover, pheophorbide a and protoporphyrin practically did not affect the total healing period but decreased the length of the inflammation stage. It was supposed that these effects are related to the generation of reactive oxygen species during irradiation.

Wound healing potential of methanolic extract of Trichosanthes dioica Roxb (fruits) in rats

AIM OF THE STUDY

The present study provides a scientific evaluation for the wound healing potential of methanolic (MeOH) extract of TDR fruits.

MATERIALS AND METHODS

Excision and incision wounds were inflicted upon three groups of six rats each. Group I was assigned as control (ointment base), Group II was treated with standard silver sulfadiazine (0.01%) cream. Group III was treated with 5% MeOH extract ointment. The parameters observed were percentage of wound contraction, epithelialization period, hydroxyproline content, tensile strength including histopathological studies.

RESULTS

It was noted that the effect produced by the extract ointment showed significant (P<0.01) healing in both the wound models when compared with control group. All parameters such as wound contraction, epithelialization period, hydroxyproline content, tensile strength and histopathological studies showed significant changes when compared to control.

CONCLUSION

The result shows that TDR extract ointment demonstrates wound healing potential in both excision and incision models.

[Analysis of alcohol mass concentration in corpse blood]

The blood alcohol concentration (BAC) is an important evidence to determine the alcohol level at the time of death. But due to the postmortem synthesis and diffusion of alcohol, the cadaveric BAC can not always represent the original BAC at the time of death. It is a crucial problem to determine the original level in corpse. The article reviewed the following points: the distribution in corpse, and how to sample, the influences on the diffusion of alcohol and putrefaction, the discussion about alcohol mass concentration measure methods.

Transglutaminases, involucrin, and loricrin as markers of epidermal differentiation in skin substitutes derived from human sweat gland cells

BACKGROUND/PURPOSE

In a multi-project research line, we are currently testing whether a morphologically and functionally near normal epidermis can be cultured from human sweat gland (SG) cells and be used as a skin substitute. The present study focuses on the stratum corneum of the epidermis that assumes a vital barrier function for the skin. The main process in the formation of the cornified cell envelope in human epidermis, i.e. crosslinking of proteins and lipids, is catalyzed by several transglutaminases (TG). Therefore, we compared the expression patterns of various TG and their substrates in SG-derived versus keratinocyte-derived epidermal substitutes.

METHODS

Sweat gland cells, keratinocytes, and fibroblasts were isolated from human skin samples and cultivated separately to generate epidermal substitutes. These were transplanted onto the back of athymic rats. After 2 weeks, the transplants were excised and analyzed histologically as well as by indirect immunofluorescence. We looked at the expression of TG1, 3, 5, and their substrates involucrin and loricrin (=markers of epidermal differentiation) in SG-derived and keratinocyte-derived skin substitutes as well as in normal skin.

RESULTS

The SG cell-derived epidermis was near normal anatomically, formed a cornified cell envelope and demonstrated TG1, 3, and 5 as well as involucrin and loricrin expression patterns similar to those found in keratinocyte-derived epidermis and normal control skin.

CONCLUSION

These findings support the thesis that SG cells have the potential to form a near normal stratified epidermal analog that might be used as a skin substitute. The expression of TG1 and 3, not normally expressed in human SG, suggests the presence of re-programmed SG cells and/or stem cells capable of both de novo generating and maintaining an epidermis.

[Expression of FAP and alpha-SMA during the incised wound healing in mice skin]

OBJECTIVE To investigate the time-dependent expression of fibroblast activation protein (FAP) and alpha-smooth muscle actin(alpha-SMA) during the incised wound healing of the skin in mice.

METHODS

The expression of FAP and alpha-SMA in incised wound of mice skin was detected by immunohistochemistry and Western blot.

RESULTS

By immunohistochemistry, the expression of FAP and alpha-SMA in the normal skin and the skin 1 h after injury maintained at a very low level, but the positive cells expressing FAP and alpha-SMA started to elevate 6 h after injury and reached its peak on 5 d for FAP and on 3 d for alpha-SMA, then gradually decreased to the normal level on 14 d. The expression of FAP and alpha-SMA was observed throughout the wound healing stages 1 d after injuries by Western blot as well with a peak expression occurring on 5 d for FAP and on 3 d for alpha-SMA after injury.

CONCLUSION

FAP may be a potentially useful marker for wound age determination and alpha-SMA may be used as an effective indicator for the mid- and late stage incised wound of mice skin. The combination use of FAP and alpha-SMA may be potentially effective indicators for wound age determination.

[Expression of c-jun during the incised wound healing in mice skin]

OBJECTIVE To investigate the time-dependent expression of c-jun during the healing of incised wound in mice skin.

METHODS

The expression of c-jun in different stages after the incised wound were detected by immunohistochemistry and Western blot.

RESULTS

There was a low level expression of c-jun in normal mice skin. Expression of c-jun was mainly detected in neutrophils from 3 h to 12h after injury. The c-jun positive cells were almost mononuclear cells (MNCs) and fibroblasts between 1 d and 5 d after injury. The c-jun positive cells were mostly fibroblasts between 7 d and 14 d after injury. The ratio of the c-jun positive cells increased in the wound specimens from 3 h to 12 h, peaked at 12 h, declined partially from 1 d to 5 d, and reached the peak secondly at 7 d, then decreased from 10 d to 14 d. The expression of c-jun was observed throughout the wound healing stages by Western blot with two peaks occurring at 12 h and 7 d after injury.

CONCLUSION

The c-jun may play a potential role in inducing apoptosis of neutrophils, MNCs and fibroblasts during skin wound healing, and it may be used as the marker for wound age determination.

Age and tissue specific differences in the development of acute insulin resistance following injury

Injuries, hemorrhage, sepsis, burn, and critical illnesses all induce insulin resistance, and insulin resistance is strongly associated with advancing age. However, the effect of age on injury induced insulin resistance is not well studied. We performed surgical trauma in male rats of three different ages (3-, 6-, and 10-weeks old). Rats were either hemorrhaged to a mean arterial pressure of 35-40 mmHg and subsequently maintained at that pressure for up to 90 min, or maintained without hemorrhage as controls. Results indicate that insulin-induced intracellular signaling was diminished in liver and skeletal muscle of 6- and 10-week old rats following trauma and hemorrhage. In even younger rats, immediately post-weaning ( approximately 3 weeks of age), insulin signaling was lost in liver, but not in skeletal muscle. Glucocorticoids can play a role in the chronic development of insulin resistance. Our results demonstrate that corticosterone levels were increased in 6- and 10-week old animals following hemorrhage, but little change was measured in 3-week old animals. Blockade of glucocorticoid synthesis prevented the development of insulin resistance in skeletal muscle, but not in liver of 6- and 10-week old rats. Moreover, skeletal muscle glucocorticoid receptor levels increased dramatically between 3 and 6 weeks of age. These results indicate that trauma and hemorrhage-induced hepatic insulin resistance occurs at all ages tested. However, there is no development of insulin resistance following trauma and hemorrhage in skeletal muscle of post-weaning rats. In skeletal muscle of 6- and 10-week old rats, inhibition of glucocorticoid levels prevents the development of insulin resistance.

[Effect of cytoflavine on bioenergetic processes in the liver after severe limb compression trauma]

The experiments on rats showed that severe compression trauma of limb muscles leads to a decrease in the energetic potential of the liver. Cytoflavine injected in rats with model traumas increased the content of ATP and cAMP and decreased the level of ADP and AMP, thus recovering the energetic potential of adenine nucleotides in the liver.

[P-selectin and its role in some diseases]

P-selectin is an adhesion molecule located in the platelet a granule and Weibel-Palade body of endothelial cells. P-selectin mediates the rolling of blood cells on the surface of the endothelium and initiates the attachment of leukocytes circulating in the blood to platelets, endothelial cells,and other leukocytes at sites of tissue injury and inflammation. These processes are possible because ligands for P-selectin are present on the surface of platelets and endothelial cells which undergo sulfation of a specific tyrosine residue at its N-terminal for P-selectin recognition. P-selectin glycoprotein ligand-1 (PSGL-1) is a major ligand for P-selectin which is responsible for leukocyte rolling on active endothelium. Glycoprotein GPIb mediates platelet adhesion to subendothelium at sites of injury and the rolling of inactivated platelets on its activated surface. Sulfatides are ligands for P-selectin, which plays a role in platelet aggregation and adhesion. Soluble P-selectin (sP-selectin) is presents in the blood and circulates in normal humans in concentrations of ca. 100 ng/ml. An increased level of sP-selectin is a major predictive factor of cardiovascular events related to platelet turnover and its activation and function. P-selectin plays a key role in diseases associated with injury and arterial thrombosis. Increased expression of P-selectin is observed in coronary artery disease, acute myocardial infarction, stroke, and peripheral artery diseases. The pathogenesis of thrombosis in cancer patients is related to dysfunction of endothelial cells, active involvement of leukocytes, and increased number and activity of platelets. Increased level of sP-selectin and elevated P-selectin expression may be good markers of some types of carcinoma,such as neoplastic pulmonary diseases, breast, renal, and colon cancer, and blood cancer.

[Stem cells of intestine epithelium. Survival mechanisms and microbiota role]

The thanatogenetic mechanisms of stem cells (SC) of rapidly renewing system of intestinal epithelium still remain unclear. On the one hand, they are definitely involved into basic mechanisms of carcinogenesis in the gastrointestinal tract, because dysregulation of programs responsible for elimination of "unwanted" mutant cells (which are normally under immune and own intrinsic control) is one of the reasons of neoplastic expansion. On the other hand, elucidation and characterization of the regulatory machinery controlling SC survival are interrelated with problems of clinical medicine, including the increase of therapeutic efficiency of treatment of inflammatory and ulcer lesions of the gut, traumatic and surgical wounds, as well as restriction of side effects in normal tissues induced by application of intensive methods chemo- and radiotherapy of cancer. The latter is especially important for treatment of blood diseases and tumors of peritoneal cavity organs mainly due to bone marrow and intestinal epithelium damage. (These tissues are the most sensitive to these treatments.) The review considers data on exogenous and genetic modifiers of SC survival, and also the basic principles of mechanisms involved into renewal and regeneration of SC and the effects of microbiota on these processes.

Regulation of Nitric Oxide Synthesis in Wounds by IFN-γ Depends on TNF-α

Macrophage-derived nitric oxide is a critical mediator in wound healing. Its regulation in vivo, however, remains unclear. We hypothesized that interferon (IFN)-gamma plays an important role in the regulation of nitric oxide in wounds. Groups of 12 male IFN-gamma -knockout mice and wild-type controls underwent dorsal skin incision and polyvinyl alcohol sponges were inserted subcutaneously. Mice were sacrificed 10 days later to determine wound breaking strength and reparative collagen deposition. Synthesis of nitric oxide (NO), tumor necrosis factor (TNF)-alpha, and IFN-gamma was measured in the wound. Wound-derived macrophages were tested for NO synthesis in the presence or absence of IFN-gamma, TNF-alpha, and anti-TNF-alpha antibody. In a separate experiment, IFN-gamma -knockout mice and wild-type controls were treated with molsidomine, a nitric oxide donor. It was found that wound collagen deposition and wound breaking strength were impaired in IFN-gamma-knockout mice (p < .05). Impaired healing was reflected in diminished synthesis of TNF-alpha and NO in wounds (p < .05). In vivo treatment with molsidomine reversed impaired healing in IFN-gamma-deficient mice. Ex vivo, addition of IFN-gamma stimulated the synthesis of TNF-alpha and NO in wound-derived macrophages. IFN-gamma -induced NO synthesis by wound-derived macrophages was abolished by anti-TNF-alpha-antibody-treatment, which could be fully reversed by exogenous TNF-alpha. Thus we conclude that IFN-gamma-deficiency impairs wound healing and diminishes NO synthesis in wound-derived macrophages. The stimulatory effect of IFN-gamma on macrophage NO production depends on endogenous TNF-alpha synthesis.

Distributions of glucocorticoid receptor gene polymorphisms in a Chinese Han population and associations with outcome after major trauma

AIM

To investigate in a Chinese population the occurrence of polymorphisms Bcl I, N363S and ER22/23EK in the glucocorticoid receptor and their association with outcome of trauma.

METHODS

In all, 266 healthy volunteers and 95 victims of major trauma were recruited. The presence of glucocorticoid receptor polymorphisms (ER22/23EK, N363S and Bcl I) was sought by restriction fragment length polymorphism analysis. The injured group were monitored as to respiratory, renal, hepatic, cardiovascular, haematological and central nervous functions. The association was determined between polymorphisms and the development of multiple organ dysfunction syndrome and sepsis after trauma.

RESULTS

Only the Bcl I polymorphism was identified. The frequency of its G allele was 23.5% among volunteers and 26.3% among casualties. There were no significant differences in MOD score or sepsis rate between participants classified according to genotype.

CONCLUSIONS

Only the Bcl I polymorphism of the glucocorticoid receptor gene is common in the Chinese Han population; it may not influence the development of complications following major trauma.

Upregulation of gamma-2 laminin-332 in the mouse ear vesicant wound model

Epithelial cell migration during wound healing is regulated in part by enzymatic processing of laminin-332 (formerly LN-5), a heterodimer formed from alpha, beta, and gamma polypeptide chains. Under static conditions, laminin-332 is secreted into the extracellular matrix as a proform and has two chains processed to smaller forms, allowing it to anchor epithelial cells to the basement membrane of the dermis. During incisional wounding, laminin gamma2 chains in particular are processed to smaller sizes and function to promote epithelial sheet migration over the wound bed. The present study examines whether this same function occurs following chemical injury. The mouse ear vesicant model (MEVM) was used to follow the pathology in the ear and test whether processed laminin-332 enhances epithelial cell migration. Skin biopsies of sulfur mustard (SM) exposed ears for several time points were analyzed by histology, immunohistochemistry, real-time PCR, and Western blot analysis. SM exposure greatly increased mRNA levels for laminin-gamma2 in comparison to the other two chains. Protein production of laminin-gamma2 was upregulated, and there was an increase in the processed forms. Protein production was in excess of the amount required to form heterotrimeric laminin-332 and was associated with the migrating epithelial sheet, suggesting a potential role in wound healing for monomeric laminin-gamma2.

Bone marrow stromal cells attenuate injury-induced changes in galanin, NPY and NPY Y1-receptor expression after a sciatic nerve constriction

Single ligature nerve constriction (SLNC) of the rat sciatic nerve triggers neuropathic pain-related behaviors and induces changes in neuropeptide expression in primary afferent neurons. Bone marrow stromal cells (MSCs) injected into the lumbar 4 (L4) dorsal root ganglia (DRGs) of animals subjected to a sciatic nerve SLNC selectively migrate to the other ipsilateral lumbar DRGs (L3, L5 and L6) and prevent mechanical and thermal allodynia. In this study, we have evaluated the effect of MSC administration on the expression of the neuropeptides galanin and NPY, as well as the NPY Y(1)-receptor (Y(1)R) in DRG neurons. Animals were subjected to a sciatic nerve SLNC either alone or followed by the administration of MSCs, phosphate-buffered saline (PBS) or bone marrow non-adherent mononuclear cells (BNMCs), directly into the ipsilateral L4 DRG. Seven days after injury, the ipsilateral and contralateral L4-5 DRGs were dissected out and processed for standard immunohistochemistry, using specific antibodies. As previously reported, SLNC induced an ipsilateral increase in the number of galanin and NPY immunoreactive neurons and a decrease in Y(1)R-positive DRG neurons. The intraganglionic injection of PBS or BNMCs did not modify this pattern of expression. In contrast, MSC administration partially prevented the injury-induced changes in galanin, NPY and Y(1)R expression. The large number of Y(1)R-immunoreactive neurons together with high levels of NPY expression in animals injected with MSCs could explain, at least in part, the analgesic effects exerted by these cells. Our results support MSC participation in the modulation of neuropathic pain and give insight into one of the possible mechanisms involved.

[Research of the relationship between insulin signal transduction and glucose transportation in rats after trauma]

OBJECTIVE

To investigate the relationship between insulin post-receptor signal transduction and the change of glucose transportation by skeleton muscle after surgical trauma in rats.

METHODS

Small intestine bowel resection was performed to establish the surgical trauma model in rats. The content and the phosphorylation state of two key proteins in the insulin signaling pathway: insulin receptor substrate-1 (IRS-1) and protein kinase B (PKB/Akt) in skeletal muscle were measured respectively. The 3H labeled glucose uptake experiment was carried out to evaluate the glucose transportation function in both groups. Finally, the expression and the distribution of glucose transporter 4 (GLUT4) in skeletal muscle were detected respectively.

RESULTS

The total content of IRS-1 and PKB/Akt in skeletal muscle in both groups had no difference. The phosphorylation of tyrosine (Tyr) residue of IRS-1 in the operation group was attenuated by 31% (P = 0.018), whereas the phosphorylation of serine (Ser) residue of IRS-1 was significantly enhanced by 63% compared with the control group (P = 0.000). Accordingly, the phosphorylation state of PKB/Akt (activated) was attenuated by 48% in the operation group (P = 0.000). The rate of 2-Deoxy-D-[1-3H] glucose transported by skeletal muscle in the operation group was significantly lower than that in the control group. Both the expressions of GLUT-4 mRNA and the total content of GLUT-4 protein in two groups had no significant difference. But the expression of GLUT4 in the plasma membrane was decreased in the operation group than that in the control group.

CONCLUSIONS

Insulin resistance was associated with enhanced Ser phosphorylation of IRS-1, which impaired its interaction with its downstream target PKB/Akt. Such impaired interactions abolished the ability of IRS-1 to undergo insulin-induced Tyr phosphorylation and further propagate the insulin receptor signal. Uncoupling of signal transduction led to decrease in glucose uptake which associated with a defect in insulin-stimulated glucose transport and GLUT-4 translocation.

Near-infrared imaging of injured tissue in living subjects using IR-820

The unprecedented increase in preclinical studies necessitates high-throughput, inexpensive, and straightforward methods for evaluating diseased tissues. Near-infrared imaging of live subjects is a versatile, cost-effective technology that can be effectively used in a variety of pathologic conditions. We have characterized an inexpensive optoelectronic chemical, IR-820, as an infrared blood pool contrast agent to detect and quantify diseased tissue in live animals. IR-820 has maximal excitation and emission wavelengths of 710 and 820 nm, respectively. IR-820 emission is significantly improved in vivo on serum binding to albumin, and elimination occurs predominantly via the gastrointestinal tract. We demonstrate the utility of this contrast agent for serially imaging of traumatized tissue (muscle), tissue following reperfusion (eg, stroke), and tumors. IR-820 can also be employed to map regional lymph nodes. This novel contrast agent is anticipated to be a useful and an inexpensive tool for screening a wide variety of preclinical models of human diseases.

Attenuation of lung inflammation and pro-inflammatory cytokine production by resveratrol following trauma-hemorrhage

Although studies have demonstrated that resveratrol administration following adverse circulatory conditions is known to be protective, the mechanism by which resveratrol produces the salutary effects remains unknown. We hypothesized that resveratrol administration in males following trauma-hemorrhage decreases cytokine production and protects against lung injury. Male Sprague-Dawley rats underwent trauma-hemorrhage (mean blood pressure 40 mmHg for 90 min, then resuscitation). A single dose of resveratrol (30 mg/kg of body weight) or vehicle was administered intravenously during resuscitation. Twenty-four hours thereafter, tissue myeloperoxidase activity (a marker of neutrophil sequestration), cytokine-induced neutrophil chemoattractant (CINC)-1, CINC-3, intercellular adhesion molecule (ICAM)-1, and interleukin (IL)-6 levels in the lung and protein concentrations in bronchoalveolar lavage fluid were measured (n = 6 rats/group). One-way ANOVA and Tukey's test were used for statistical analysis. Trauma-hemorrhage increased lung myeloperoxidase activity, CINC-1, CINC-3, ICAM-1, and IL-6 levels and protein concentrations in bronchoalveolar lavage fluid. These parameters were significantly improved in the resveratrol-treated rats subjected to trauma-hemorrhage. The salutary effects of resveratrol administration on attenuation of lung injury following trauma-hemorrhage are likely due to reduction of pro-inflammatory mediators.

Arginine metabolism and nutrition in growth, health and disease

L-Arginine (Arg) is synthesised from glutamine, glutamate, and proline via the intestinal-renal axis in humans and most other mammals (including pigs, sheep and rats). Arg degradation occurs via multiple pathways that are initiated by arginase, nitric-oxide synthase, Arg:glycine amidinotransferase, and Arg decarboxylase. These pathways produce nitric oxide, polyamines, proline, glutamate, creatine, and agmatine with each having enormous biological importance. Arg is also required for the detoxification of ammonia, which is an extremely toxic substance for the central nervous system. There is compelling evidence that Arg regulates interorgan metabolism of energy substrates and the function of multiple organs. The results of both experimental and clinical studies indicate that Arg is a nutritionally essential amino acid (AA) for spermatogenesis, embryonic survival, fetal and neonatal growth, as well as maintenance of vascular tone and hemodynamics. Moreover, a growing body of evidence clearly indicates that dietary supplementation or intravenous administration of Arg is beneficial in improving reproductive, cardiovascular, pulmonary, renal, gastrointestinal, liver and immune functions, as well as facilitating wound healing, enhancing insulin sensitivity, and maintaining tissue integrity. Additionally, Arg or L-citrulline may provide novel and effective therapies for obesity, diabetes, and the metabolic syndrome. The effect of Arg in treating many developmental and health problems is unique among AAs, and offers great promise for improved health and wellbeing of humans and animals.

Tissue oxygen saturation predicts the need for early blood transfusion in trauma patients

Near-infrared spectroscopy (NIRS) has been used to measure regional tissue oxygen saturation (StO2) in skeletal muscle as an indicator of perfusion in trauma patients. In an effort to prospectively examine the usefulness of StO2 in identifying trauma patients in hemorrhagic shock, we evaluated the need for blood transfusion within 24 hours of injury as a marker of significant hemorrhage. A 6-month prospective, observational study was conducted at a university-affiliated, urban Level I trauma center using a convenience sample of 26 trauma patients thought to be at high risk for hemorrhagic shock. Baseline demographic data, vital signs, laboratory values, and amounts of fluid and blood products administered were collected. NIRS-derived StO2 values were measured for 1 hour after arrival to the trauma bay and the minimum value noted. A minimum StO2 less than 70 per cent correlated with the need for blood transfusion with a sensitivity of 88 per cent and a specificity of 78 per cent. The positive predictive value was 64 per cent and the negative predictive value was 93 per cent. The need for blood transfusion within 24 hours of arrival was not predicted by hypotension, tachycardia, arterial lactate, base deficit, or hemoglobin. StO2 may represent an important screening tool for identifying trauma patients who require blood transfusion or other limited medical resources.

[The potential role of high mobility group box 1 protein in immune dysfunction and its regulatory mechanism after major trauma]

OBJECTIVE

To investigate the potential effect of high mobility group box 1 protein (HMGB1) on host immune response and its molecular regulation mechanism as well as its interventional pathway following major burns/trauma.

METHODS

With both animal experiments and clinical investigation, serial studies were conducted to observe the effects of HMGB1 on changes in immune function of T lymphocytes, dendritic cells, and macrophages both in vivo and in vitro.

RESULTS

It was found that thermal injury or trauma induced a delayed and persistent increase in HMGB1 expression as well as its release in various tissues. HMGB1 formation could markedly influence the cell-mediated immunity, including the changes in T lymphocytes, dendritic cells, and macrophages following major trauma or burns. These effects were closely related with dysfunction of various organs in the course of sepsis.

CONCLUSION

These data proved that HMGB1 not only acts as a novel "late" inflammatory mediator but is also closely associated with immunosuppression after acute insults. HMGB1 might play an important role in inducing systemic inflammatory response together with host immunological dissonance, resulting in the development of septic complications. Intervention of HMGB1 expression and release presumably provides a potentially effective way to regulate both excessive inflammatory and immune response, thereby as a measure to improve the prognosis of severe sepsis secondary to major trauma.

Activation of endoplasmic reticulum stress response following trauma-hemorrhage

Hemorrhagic trauma leads to organ dysfunction, sepsis and death. There is abnormal production of proinflammatory cytokines by Kupffer cells, tissue hypoxia and liver injury following trauma-hemorrhage. The physiological conditions consequent to trauma-hemorrhage are consistent with factors necessary to initiate endoplasmic reticulum (ER) stress and unfolded protein response. However, the contribution of ER stress to apoptosis and liver injury after trauma-hemorrhage is not known. In the present study ER stress was investigated in mice that underwent trauma-hemorrhage or sham operation. Expressions of endoplasmic reticulum stress proteins Bip, ATF6, PERK, IRE1alpha, and PDI were significantly elevated in the liver after trauma-hemorrhage compared to the controls. The ER stress associated proapoptotic transcription factor CHOP protein expression was also significantly elevated in trauma-hemorrhage group. Consistent with this, enhanced DNA fragmentation was observed, confirming apoptosis, in the liver following trauma-hemorrhage. These results demonstrate the initiation of ER stress and its role in apoptosis and liver injury, subsequent to hemorrhagic trauma.

Erythropoietin measurements in severely traumatized patients

BACKGROUND

Despite numerous studies in critically ill patients, physiological adaptation to acute anaemia and the pattern of erythropoietin (EPO) secretion has not been well described in severely injured patients. The aim of this study was to describe EPO secretion and its relationship with haemoglobin (Hb) levels in severely injured patients.

METHODS

We performed an observational, prospective clinical study in our intensive care unit (ICU). For all patients with severe trauma (Injury Severity Score>15), EPO measurement was obtained on admission, during the first 3 days and then when Hb level was measured. Maximal EPO level (EPOmax) and minimal Hb level (Hbmin) during the ICU stay was determined for all patients.

RESULTS

One hundred and seventy-one consecutives patients were included (440 EPO measurements). Seventy-nine patients (46.2%) showed an increased value (> or =25 UI/l) EPOmax value. Most EPOmax values were observed early after the trauma [within 4 days for 63 patients (82.8%)]. Plotting EPOmax to Hbmin values show that a threshold Hbmin value of 105 g/l best discriminated patients with and without an elevated EPO secretion. Less than 10% of the patients with Hbmin<105 g/l did not increase their EPO secretion.

CONCLUSION

In severely traumatized patients a marked response to acute anaemia is observed in most patients. In our study, Hb threshold for a significant EPO secretion following post-traumatic acute anaemia was 105 g/l. The peak level was achieved early in the course of the anaemia.

Melatonin, consciousness, and traumatic stress

Descartes intuitively anticipated the so-called 'binding problem' of consciousness and thought that the pineal gland enables spatio-temporal integration in cognitive processing. Recent findings indicate that a major role in the process of temporal integration and binding involve neurons in suprachiasmatic nuclei, specifically targeting the pineal gland and other structures, and control the neuroendocrine rhythms. Melatonin is an endocrine output signal of the clock and provides circadian information as an endogenous synchronizer which stabilizes and reinforces circadian rhythms. This integrative process occurs at the different levels of the circadian network via gene expression in some brain regions and peripheral structures that enables integration of circadian, hormonal, and metabolic information and creating temporal order of bodily and mental experience. This specific temporal order is reflected in associative sequentiality that is necessary for cognition, behavior and all processes of memory consolidation that must preserve all information in the temporal causal order and synchrony. In this context, recent findings suggest that melatonin could be a potential regulator in the processes that contribute to memory formation, long-term potentiation, and synaptic plasticity in the hippocampus and other brain regions. There is evidence that stress disrupts normal activity and memory consolidation in the hippocampus and prefrontal cortex, and this process leads to memories that are stored without a contextual or spatiotemporal frame. These findings emphasize a specific role of melatonin in mechanisms of consciousness, memory and stress and are also consistent with reported studies that indicate melatonin alterations under stressful conditions and in mental disorders.

Sirtinol attenuates hepatic injury and pro-inflammatory cytokine production following trauma-hemorrhage in male Sprague-Dawley rats

BACKGROUND

Although studies have demonstrated that sirtinol administration following adverse circulatory conditions is known to be protective, the mechanism by which sirtinol produces the salutary effects remains unknown. We hypothesized that sirtinol administration in male rats following trauma-hemorrhage decreases cytokine production and protects against hepatic injury.

METHODS

Male Sprague-Dawley rats underwent trauma-hemorrhage (mean blood pressure 40 mmHg for 90 min, then resuscitation). A single dose of sirtinol (1 mg/kg of body weight) or vehicle was administered intravenously during resuscitation. Twenty-four hours thereafter, tissue myeloperoxidase (MPO) activity (a marker of neutrophil sequestration), cytokine-induced neutrophil chemoattractant (CINC)-1, CINC-3, intercellular adhesion molecule (ICAM)-1, and interleukin (IL)-6 levels in the liver and plasma alanine aminotransferase (ALT) concentrations were measured (n=6 Sprague-Dawley rats/group).

RESULTS

Trauma-hemorrhage increased hepatic MPO activity, CINC-1, CINC-3, ICAM-1, and IL-6 levels and plasma ALT concentrations. These parameters were significantly improved in the sirtinol-treated rats subjected to trauma-hemorrhage.

CONCLUSION

The salutary effects of sirtinol administration on attenuation of hepatic injury following trauma-hemorrhage are, at least in part, related to reduction of pro-inflammatory mediators.

Effect of N. sativa oil on impaired glucose tolerance and insulin insensitivity induced by high-fat-diet and turpentine-induced trauma

The aim of this study was to investigate the effect of N. sativa oil on impaired glucose tolerance and insulin insensitivity induced by high-fat diet and trauma. Three dietary groups were used in this study; Rat-Chow (RC), N. sativa oil diet (Combination 4% N. sativa oil and 16% butter oil) (NSOD) and 20% Butter Oil Diet (BOD). Each group was subdivided in two groups; control and trauma. Diets were supplemented for five consecutive weeks body weight increase per week was calculated. At end of the dietary treatments, single dose (2 mL kg(-1) body weight) of turpentine was injected in the dorso-lumber region. Intravenous glucose tolerance test (i.v. GTT) was performed, insulinogenic index and insulin sensitivity was measured. The results showed butter oil diet significantly increased the body weights and visceral fats compared other two groups, respectively. Fasting glucose levels did not change in trauma induced rats while insulin levels increased significantly and it found highest in butter oil diet fed animals. Impaired glucose tolerance was found sever in BOD fed traumatized rats. N. sativa oil diet protected impaired glucose tolerance and insulin insensitivity induced either via saturated fatty acids or injury. In conclusion, N. sativa oil may be used in post surgery diabetic patients to prevent the long going adverse effects from surgical trauma.

HEXOSAMINE BIOSYNTHESIS AND PROTEIN O-GLYCOSYLATION

An early and rapid response to severe injury or trauma is the development of hyperglycemia, which has long been thought to be an essential survival response by providing fuel for vital organ systems and facilitating mobilization of interstitial fluid reserves by increasing osmolarity. However, glucose can also be metabolized via the hexosamine biosynthesis pathway (HBP), leading to the synthesis of uridine diphosphate N-acetyl-glucosamine(UDP-GlcNAc). UDP-GlcNAc is a substrate for the addition, via an O-linkage, of a single N-acetylglucosamine to serine or threonine residues of nuclear and cytoplasmic proteins (O-glycosylation, O-GlcNAc). There is increasing appreciation that protein O-glycosylation is a highly dynamic posttranslational modification that plays a key role in signal transduction pathways. Sustained increases in O-GlocNAc have been implicated in the development of diabetes and diabetic complications; however, recent studies have demonstrated that stress leads to a transient increase in O-GlcNAc levels that is associated with increased tolerance to stress. Indeed, activation of pathways leading to O-GlcNAc formation improves cell survival after I/R injury, whereas inhibition of O-GlcNAc formation decreases cell survival. In addition, in rodent models of trauma-hemorrhage, increasing O-GlcNAc levels during resuscitation improves cardiac function and organ perfusion and attenuates the inflammatory response. At the cellular level, increasing O-GlcNAc levels attenuates nuclear factor-kappaB activation. It is noteworthy that other metabolic-based treatments for severe injury such as glucose-insulin-potassium and glutamine also lead to increased HBP flux and O-GlcNAc levels. The goal of this review is to summarize our current understanding of the role of the HBP and O-GlcNAc on the regulation of cell function and survival and to present evidence to support the notion that activation of these pathways represents a novel treatment strategy for severe injury and trauma.

[Noninvasive quantification of glutamine and glutamate in skeletal muscles of perioperative rabbits with proton magnetic resonance spectroscopy]

OBJECTIVE

To evaluate the feasibility of noninvasive quantification of the metabolic changes of glutamine (Gln) and glutamate (Glu) in the skeletal muscles caused by abdominal surgery with proton magnetic resonance spectroscopy (MRS).

METHODS

Abdominal surgery were performed on 15 healthy Zelanian rabbits. MRS data, blood specimens, and muscular tissues were obtained on the day before surgery and the second day after surgery. MRS data included peak amplitude and peak area of Gln + Glu (Glx) and total creatine (TCr). The reproducibility of peak amplitude with peak area was compared and the better one was chosen to calculate the ratio of Glx to TCr. Free Gln and Glu concentrations in serum and muscles were analyzed by reversed phase high-performance liquid chromatography (RP-HPLC). The results of MRS were compared with those of RP-HPLC to evaluate the feasibility of MRS application in Gln and Glu metabolism.

RESULTS

Peak amplitude had better reproducibility than peak area under our conditions. The coefficient of variation (CV) of the ratio of the amplitude of Glx to TCr was (15.62 +/- 9.87)%. The ratio of the amplitude of Glx to TCr significantly decreased on the second day after surgery (P <0.05, P <0.01). The mean free Glx concentrations in both the serum and the muscles different were not significant between on the second day after surgery and on the day before surgery.

CONCLUSIONS

The results of MRS application in reflecting the effects of surgical trauma on muscular Glx metabolism are consistent with those of RP-HPLC. It is feasible to apply MRS in the study of muscular Gln and Glu metabolism.

[Influence of maggot secretion on expression of bFGF and connective tissue growth factor in ulcer tissue of diabetes mellitus rat and antibacterium study]

OBJECTIVE

To study the influence of maggot secretion on expression of bFGF and connective tissue growth factor (CTGF) in ulcer tissue of diabetes mellitus (DM) rats and its antibacterial function.

METHODS

There were 40 3-month-old SD male rats (weighing 300-350 g) which were randomly divided into 2 groups: control group and experimental maggot secretion group. The model of ulcer wound of DM rats was made. The ulcer wound of DM rats in maggot secretion group spread maggot secretions, but no secretion on ulcer wound was found in control group. The morphological and tissue changes of ulcer wound were observed at different times, and the conditions of bacterial infection on ulcer wound in the two groups were checked. Tissue slices were prepared on 7, 14 and 21 days, respectively; immunohistological detection of bFGF and CTFG in ulcer wound of the two groups was done; and the cell number of positive expression of bFGF and CTFG was counted.

RESULTS

It was found that the healing of ulcer was dominant in experimental group; the wound was clean; the tissue regenerated and no Staphylococcus aureus infection was seen. Bad healing was obtained in control group; tissue necrosis was found and the rate of Staphylococcus aureus infection was 60%. Positive expression cell number of bFGF in ulcer wound was detected on 7 and 14 days after operation with 23.76 +/- 3.34 and 52.76 +/- 4.84 in experimental group, and 18.88 +/- 2.16 and 46.04 +/- 4.00 in control group. Positive expression cell number of CTGF in ulcer wound was detected on 7 and 14 days after operation with 18.76 +/- 3.24 and 46.52 +/- 4.07 in experimental group, and 12.52 +/- 3.03 and 40.52 +/- 3.96 in control group. There was significant difference between positive expressions of bFGF and CTFG in the two groups (P < 0.05).

CONCLUSION

The maggot secretion can elevate the expressions of bFGF and CTFG in ulcers, promote healing and prevent bacterial infection.

Absorption of bioactive molecules into OASIS wound matrix

OBJECTIVE

To examine the ability of OASIS Wound Matrix to absorb, retain, and protect bioactive molecules from solution.

DESIGN

Samples of OASIS Wound Matrix were incubated in solutions of bioactive molecules, specifically heparin, albumin, fibronectin, basic fibroblast growth factor 2, and platelet-derived growth factor (PDGF). Half of the samples were then rinsed, and all of the samples were evaluated using enzyme-linked immunosorbent assays (ELISAs) and dye-mediated spectrophotometric methods for absorption and retention of the bioactive molecules. Protection of PDGF was measured by placing PDGF-incubated and control samples into a degradation solution containing plasmin. Intact PDGF levels were then evaluated using a PDGF-specific ELISA.

MAIN OUTCOME MEASURES

The main outcome measures were the amount of each bioactive molecule that was absorbed after incubation in solutions and retained after rinses as well as the amount of PDGF remaining after plasmin degradation.

MAIN RESULTS

OASIS Wound Matrix absorbed bioactive molecules from solution, selectively absorbed PDGF from serum, and protected PDGF from protease degradation.

CONCLUSIONS

Although OASIS Wound Matrix potentially has multiple functions in wound healing, it likely promotes wound healing, in part, by absorbing, retaining, and protecting bioactive molecules from the wound environment.

Levels of glutathione and some biogenic amines in the human brain putamen after traumatic death

Mexico City is among the world's largest metropolitan city centers and one of the most difficult and challenging cities in which to drive a motor vehicle. During peak transit hours and maximum congestion, numerous accidents occur, many of them fatal. The aim of the study presented here was to analyze the levels of select indicators against oxidative stress and levels of biogenic amines as a consequence of accident or altercation and fear deaths. Eighteen cases were studied (sixteen males, two females). Subjects ranged from twelve to eighty-one years of age. Nine of the deaths studied were the result of motor vehicle or subway accidents. Eight of the eighteen deaths were the result of a violent altercation, while one of the deaths resulted from a drug overdose and cardiac arrest. Biopsies of cadaver putamen were homogenized and analyzed for Tryptophan (Trp), 5-hydroxyindole acetic acid (5-HIAA), Dopamine (DA), and Glutathione (GSH) levels by fluorometric methods. Trp, 5-HIAA, DA, and GSH levels showed an increase in the subjects who's death was caused by violent altercation combined with fear, while DA levels showed significant differences in all accident groups. This data suggest that biogenic amines in cadaver putamen tissue, such as DA, can be telling biochemical markers, indicative of altercation and fear deaths.

Overexpression of the elongation factor 1A1 relates to muscle proteolysis and proapoptotic p66(ShcA) gene transcription in hypercatabolic trauma patients

The eukaryotic elongation factors (eEF1A2 and eEF1A1) play a key role in translation of messenger RNA (mRNA) to protein. In skeletal muscle of healthy humans, EEF1A2 is overexpressed and selected over EEF1A1. In cellular stress models, muscle EEF1A1 expression increased and was associated with apoptosis and catabolism. We have determined mRNA levels of EEF1A1 and EEF1A2, as well as those of other proapoptotic genes, such as p66(ShcA) and c-MYC, in skeletal muscle of severely traumatized patients and healthy volunteers. Muscle protein kinetic was determined by stable isotopes and the arteriovenous technique. The patients were in a hypercatabolic condition because the rate of muscle proteolysis exceeded that of synthesis. Mean mRNA levels of EEF1A1 and EEF1A2 were 165- and 29-fold greater (P < .01) in patients than in the control group, respectively. Mean p66(ShcA) mRNA levels were 3-fold greater (P < .05) in patients than in the controls. In contrast, c-MYC mRNA levels were not significantly different in patients and healthy controls. In patients, muscle mRNA levels of EEF1A1 and p66(ShcA) directly correlated (P < .05) with the rate of proteolysis (R = 0.901 and R = 0.826, respectively). This is in agreement with a reduction in actin and tubulin protein content, both markers of cytoskeletal and sarcomeric disorganization, and with an increased poly(adenosine diphosphate-ribose) polymerase cleavage, a marker of apoptosis. In conclusion, in hypercatabolic traumatized patients, an up-regulation of muscle EEF1A1 and p66(ShcA) relates to proteolysis rate, suggesting an involvement of these genes in muscle catabolic response.

Topical application of laminin-332 to diabetic mouse wounds

BACKGROUND

Keratinocyte migration is essential for wound healing and diabetic wound keratinocytes migrate poorly. Keratinocyte migration and anchorage appears to be mediated by laminin-332 (LM-332). Impaired diabetic wound healing may be due to defective LM-332 mediated keratinocyte migration.

OBJECTIVE

To evaluate LM-332 expression in diabetic (db/db) and control (db/-) mice and to test LM-332 wound healing effects when applied to mouse wounds.

METHODS

LM-332 expression in mouse wounds was evaluated using immunohistochemistry. LM-332 wound healing effects were evaluated by directly applying soluble LM-332, a LM-332 biomaterial, or a control to mouse wounds. Percent wound closure and histology score, based on healing extent, were measured.

RESULTS

Precursor LM-332 expression was markedly reduced in db/db when compared to db/- mice. In vitro, soluble LM-332 and LM-332 biomaterial demonstrated significant keratinocyte adhesion. In vivo, soluble LM-332 treated wounds had the highest histology score, but significant differences were not found between wound treatments (p>0.05). No differences in percentage wound closure between treatment and control wounds were found (p>0.05).

CONCLUSION

The db/db wounds express less precursor LM-332 when compared to db/-. However, LM-332 application did not improve db/db wound healing. LM-332 purified from keratinocytes was primarily physiologically cleaved LM-332 and may not regulate keratinocyte migration. Application of precursor LM-332 rather than cleaved LM-332 may be necessary to improve wound healing, but this isoform is not currently available in quantities sufficient for testing.

Stem cell markers in the human posterior limbus and corneal endothelium of unwounded and wounded corneas

PURPOSE

The corneal endothelium is a monolayer of cells in the posterior cornea that is responsible for maintaining a clear cornea. Corneal endothelial cells may be induced to divide, but it has been held that they do not divide in the normal cornea of an adult human. Some studies have suggested that a stem cell population for the corneal endothelium exists. This population could give rise to mature corneal endothelial cells and may reside either in the peripheral corneal endothelium or in the adjacent posterior limbus. This study was initiated to demonstrate the presence of such stem cells in the region of the posterior limbus and to show the response of these cells to corneal wounding.

METHODS

Unwounded and wounded corneas with their attached limbal sections were analyzed by immunofluorescence for the presence of nestin, telomerase, Oct-3/4, Pax-6, Wnt-1, and Sox-2. Alkaline phosphatase activity was observed with an enzyme-based reaction that produced a fluorescent product.

RESULTS

In the unwounded cornea, stem cell markers nestin, alkaline phosphatase, and telomerase were found in the trabecular meshwork (TM) and in the transition zone between the TM and the corneal endothelial periphery (including Schwalbe's line). Telomerase was also present in the peripheral corneal endothelium. When wounded corneas and their attached limbii were tested, the same markers were found. However, after wounding, additional stem cell markers, Oct-3/4 (in the TM) and Wnt-1 (in both the TM and the transition zone), appeared. Moreover, the differentiation markers Pax-6 and Sox-2 were seen. Pax-6 and Sox-2 were also manifest in the peripheral endothelium post-wounding.

CONCLUSIONS

Well documented specific stem cell markers were found in the TM and the transition zone of the human posterior limbus. Wounding of the corneas activated the production of two additional stem cell markers (Oct-3/4, Wnt-1) as well as two differentiation markers (Pax-6, Sox-2), the latter of which also appeared in the corneal endothelial periphery. It is suggested that stem cells reside in the posterior limbus and respond to corneal wounding to initiate an endothelial repair process. The stem cells may also contribute to a normal, slow replacement of corneal endothelial cells.

Hyperbaric oxygen therapy mediates increased nitric oxide production associated with wound healing: a preliminary study

OBJECTIVE

The objective of this preliminary study was to document general somatic and wound nitric oxide (NO) levels during and after hyperbaric oxygen therapy (HBOT).

DESIGN

The study evaluated 6 chronic wound patients that responded favorably to HBOT treatment (20 treatments; 2.0 atmosphere absolute [ATA] x 90 minutes). Successful HBOT was associated with increased wound granulation tissue formation and significantly improved wound closure. Wound fluid and fasting plasma samples were obtained for measurement of nitrate and nitrite (NOx), the stable oxidation products of NO; plasma L-arginine (L-Arg); and asymmetric dimethylarginine (ADMA). NOx measurements were obtained before treatment (baseline), after 10 and 20 treatments, and at 1 and 4 weeks after therapy.

RESULTS

Wound fluid NOx levels tended to increase during treatments, were significantly elevated at 1 and 4 weeks after therapy, and correlated with reductions in wound area. Plasma L-Arg and ADMA were unchanged during and after HBOT.

CONCLUSION

This preliminary study documents a significant increase in local wound NO levels (by NOx measurements) after successful HBOT and suggests that this mechanism may be an important factor in promoting enhanced wound healing and wound closure associated with this therapy.

Chronische Wunde

Underlying disease may impair normal wound healing, leading to chronic, poorly healing wounds. Efficient treatment strategies require identification and treatment of the underlying disease as well as directed correction of the wound healing defect. A thorough knowledge of tissue repair mechanisms at the cellular and molecular level will help to achieve these goals. This review focuses on new developments in wound healing research and the resulting non-operative therapeutic implications.

[A study on the time-dependent expression of phospho-p38MAPK during the skin incised wound healing in mice]

OBJECTIVE

To investigate the expressions of phospho-p38MAPK(p-p38MAPK) during the incised wound healing of the skin in mice and to explore the applicability of the time-dependent expressions of p-p38MAPK in the determination of wound age.

METHODS

The expression of p-p38MAPK in incised skin wound was detected by immunohistochemistry and Western blot.

RESULTS

There was a minimal baseline expression of p-p38MAPK in control mouse skin. Expression of p-p38MAPK was mainly detectable in neutrophils in the wound specimens from 3hours to 12 hours after injury. Afterwards, the p-p38MAPK positive cells were mostly mononuclear cells and fibroblasts between post-injury day 1 and day 5, whereas the p-p38MAPK positive cells were mostly fibroblasts between post-injury day 7 and day 14. Morphometrically, the ratio of the p-p38MAPK positive cells to total number of the cells increased gradually in the wound specimens aged from 3 hours to 12 hours, and maximized in the wound specimens aged 12 hours with a slight decrease at 24 hours after injury. The ratio maintained at high level from post-injury day 3 to day 5, and then decreased gradually from post-injury day 7 to day 14. The expression of p-p38MAPK was observed throughout the wound healing stages by Western blot as well with a peak expression occurring between 12hour and day 3 after injury.

CONCLUSION

Our data suggest that p-p38MAPK may play an important role in inducing apoptosis of neutrophils, mononuclear cells, and fibroblasts during skin wound healing and meanwhile, p-p38MAPK may be a potentially useful marker for wound age determination.

[Influence of stasis-removing and muscle-regenerating Chinese hebal medicine on the expression of collagen type I and matrix metalloproteinase-1 in granulation tissue of ordinary wound]

OBJECTIVE

To understand the effects of Chinese herbal medicine for stasis -removing (SR) and muscle-regenerating (MR), in different constitutions, on granulation tissue of ordinary wound.

METHODS

Shengji Huayu recipe, a common used Chinese recipe for SR & MR (SR-MR), and its disassembled recipe, Shengji recipe (MR) and Huayu recipe (SR), were applied resectively on the full-layer skin injured wound in 120 rats to observe their effects on collagen type I (C I ) and matrix metalloproteinase-1 (MMP-1) in granulation tissue of wound at various stages of healing with immunohistochemistry technique and image-analysis system.

RESULTS

The expression of C I of the normal group was obviously delayed and the level of MMP-1 increased in a ladder type from day 3 to day 11. Shengji group could promote the secretion of C I and MMP-1 at the early stage and keep a high level from day 3 to day 11. The expression of MMP-1 of Huayu group maintained a high level on the first 7 days with significant difference as compared with the Shengji group (P < 0.05), and reduced from day 11 showing significant difference when compared with the normal group and Shengji group (all P < 0.05). Shengji Huayu low dose group has two periods of peak time in promoting the secretion of C I on day 7 and 15, and showed significant difference as compared with the normal group (P < 0.05); Shengji Huayu high dose group could reduce the MMP-1 on day 11 and obviously lower when compared with the normal group (P<0.05).

CONCLUSION

The mechanism of Chinese herbal medicine for SR-MR in promoting wound healing was probably through inhibiting the secretion of MMP-1 to increase the C I content in granulation tissue of wound.