Epidermal wound healing in severe sepsis and septic shock in humans

Introduction

The effect of sepsis on epidermal wound healing has not been previously studied. It was hypothesised that epidermal wound healing is disturbed in severe sepsis.

Methods

Blister wounds were induced in 35 patients with severe sepsis and in 15 healthy controls. The healing of the wounds was followed up by measuring transepidermal water loss and blood flow in the wound, reflecting the restoration of the epidermal barrier function and inflammation, respectively. The first set of suction blisters (early wound) was made within 48 hours of the first sepsis-induced organ failure and the second set (late wound) four days after the first wound. In addition, measurements were made on the intact skin.

Results

The average age of the whole study population was 62 years (standard deviation [SD] 12). The mean Acute Physiology and Chronic Health Evaluation II (APACHE II) score on admission was 25 (SD 8). The two most common causes of infections were peritonitis and pneumonia. Sixty-six percent of the patients developed multiple organ failure. The decrease in water evaporation from the wound during the first four days was lower in septic patients than in the control subjects (56 g/m² per hour versus 124 g/m² per hour, P = 0.004). On the fourth day, septic patients had significantly higher blood flow in the wound compared with the control subjects (septic patients 110 units versus control subjects 47 units, P = 0.001). No difference in transepidermal water loss from the intact skin was found between septic patients and controls. Septic patients had higher blood flow in the intact skin on the fourth and on the eighth day of study compared with the controls.

Conclusions

The restoration of the epidermal barrier function is delayed and wound blood flow is increased in patients with severe sepsis.

Markers of collagen synthesis and degradation are increased in serum in severe sepsis: a longitudinal study of 44 patients

Introduction

Sepsis-related multiple organ dysfunction is a common cause of death in the intensive care unit. The effect of sepsis on markers of tissue repair is only partly understood. The aim of this study was to measure markers of collagen synthesis and degradation during sepsis and investigate the association with disease severity and outcome.

Methods

Forty-four patients with severe sepsis participated in the study and 15 volunteers acted as controls. Blood samples were collected for 10 days after the first sepsis-induced organ dysfunction and after three and six months. Procollagen type I and III aminoterminal propeptides (PINP and PIIINP) and cross-linked telopeptides of type I collagen (ICTP) were measured.

Results

The PIIINP concentration was elevated in the septic patients (8.8 ug/L, 25th to 75th percentile = 6.8 to 26.0) when compared with controls (3.0 ug/L, 25th to 75th percentile = 2.7 to 3.3; P < 0.001) on day one. Maximum serum PIIINP concentrations during sepsis were higher in non-survivors compared with survivors (26.1 ug/L, 25th to 75th percentile = 18.7 to 84.3; vs. 15.1 ug/L, 25th to 75th percentile = 9.6 to 25.5; P = 0.033) and in multiple organ failure (MOF) compared with multiple organ dysfunction syndrome (MODS) (24.2 ug/L, 25th to 75th percentile = 13.4 to 48.2; vs. 8.9 ug/L, 25th to 75th percentile = 7.4 to 19.4; P = 0.002). Although the PINP values of the septic patients remained within the laboratory reference values, patients with MOF had higher values than patients with MODS (79.8, 25th to 75th percentile = 44.1 to 150.0; vs.40.4, 25th to 75th percentile = 23.6 to 99.3; P = 0.007). Day one ICTP levels were elevated in septic patients compared with the controls (19.4 ug/L, 25th to 75th percentile = 12.0 to 29.8; vs. 4.1 ug/L, 25th to 75th percentile = 3.4 to 5.0; P < 0.001).

Conclusions

Markers of collagen metabolism are increased in patients with severe sepsis and can be investigated further as markers of disease severity and outcome.

Acute edematous and necrotic pancreatitis in a porcine model

OBJECTIVE

It is unclear why pancreatitis progresses either to mild edematous disease or to severe necrotic disease. The aim of the study was to shed some light on this topic by investigating differences during the early stages of necrotic and edematous pancreatitis.

MATERIAL AND METHODS

Piglets were randomized into two groups. Necrotic pancreatitis was induced with retrograde injection of 20% taurocholic acid (1 ml/kg), and edematous pancreatitis was induced with 0.9% NaCl (1 ml/kg). Central hemodynamics was measured, and pancreatic microcirculation was directly examined by intravital microscopy. Vascular permeability to proteins and albumin was measured by microdialysis. Apoptosis and claudins 2, 3, 4, 5, and 7 were analyzed from pancreatic tissue samples. Blood samples were taken for analysis of blood cell counts, blood gases, lipase, and amylase.

RESULTS

Hemodynamic changes were similar in both groups, whereas microcirculatory impairment was more pronounced in necrotic pancreatitis. Necrosis was associated only with necrotic pancreatitis. Apoptosis increased only in edematous pancreatitis. The number of blood neutrophils and monocytes increased and lymphocyte and platelet counts decreased in both groups. Necrotic pancreatitis was associated with increased permeability to albumin and proteins. Expression of claudins 3, 4, 5, and 7 was not changed during pacreatitis, but in acinar cells, membranous expression of claudin-2 increased in both groups.

CONCLUSIONS

The results show that acute edematous pancreatitis is characterized by induction of apoptosis, whereas full-blown pancreatitis is characterized by necrosis. Impaired vascular permeability to albumin and protein is related to the early phase of necrotic pancreatitis. Claudin-2 increases during acute necrotic and edematous pancreatitis and may be related to impaired permeability.

[Effectiveness and safety of bariatric surgery]

Evidence for the effectiveness of surgical treatment of morbid obesity on life span, quality of life and associated diseases proves it an applicable alternative for the morbidly obese in cases where other means of controlling obesity have remained ineffective. The operation causes significant weight reduction even within a 15-year follow-up. Surgical mortality after an endoscopic operation is usually less than 0.5%. After the operation, patients fairly often experience various symptoms of the digestive tract. Common complications include various infections and functional disturbances associated with the band.

[Where does obesity stand in health care--every alternative into use]

Although intervention in obesity on a consultation visit, i.e. brief intervention, will only affect a portion of patients, it can reach large numbers of patients. Basic care of obesity, i.e. patient education in a group, leads to an average weight loss of 3 to 5 kg within one to two years. Basic care should be offered to patients having a condition that requires weight reduction during the treatment. In morbid obesity, surgical treatment should be promoted in Finland, although it can only be applied to a minor fraction of those requiring antiobesity treatment. Self-motivated weight control should thus be encouraged.

[Ethical aspects of bariatric surgery]

Attitude to obesity determines the attitude to antiobesity surgery: is obesity a disease among other diseases belonging to the public health care, or a characteristic resulting from living habits, remaining under the person's own responsibility? Antiobesity surgery requires supporting the patients' right to self-determination. Other treatments for obesity should be available, and this procedure necessitating permanent adjustments of living habits requires sufficient advance preparation. The patient's guarantee governing the treatment of obesity as a whole seems relevant. Assessment of the need for surgery is, however, difficult and the benefits and disadvantages differ among the various stakeholders.

[Cost-utility of bariatric surgery in the treatment for morbid obesity in Finland]

Finohta's health technology assessment report on bariatric surgery included a cost-utility analysis on three main surgical interventions used in Finland. A cost-utility analysis from the health care provider's perspective with a ten year time horizon was conducted. The parameter values were based on a representative population survey, register data, literature and expert opinions. Based on the analysis, bariatric surgery is more effective and less costly than current prevailing forms of treatment for the morbidly obese in Finland. The results were robust and consistent with previously published studies: Bariatric surgery is cost-effective in treatment of morbid obesity.

Cellular turnover and expression of hypoxic-inducible factor in acute acalculous and calculous cholecystitis

INTRODUCTION

Epithelial corrective and destructive mechanisms have not been studied in inflammatory gallbladder disease.

METHODS

Epithelial apoptosis, cell proliferation and expression of hypoxia-inducible factor (HIF)-1alpha were compared in gallbladders from patients with acute acalculous cholecystitis (AAC; n = 30) and acute calculous cholecystitis (ACC; n = 21), and from patients undergoing surgery for other reasons (normal gallbladders; n = 9), which were removed during open cholecystectomy. The immunohistochemical stains included antibodies to Ki-67 (proliferation), M30 (apoptosis) and HIF-1alpha. Proliferation and apoptosis were expressed as percentages of positive cells. HIF-1alpha expression was expressed as absent, weak, or strong.

RESULTS

Apoptosis (median [25th to 75th percentile]) was significantly increased in AAC (1.31% [0.75% to 1.8%], P < 0.001) and ACC (1.10% [0.63% to 1.64%], P = 0.001), compared with control samples (0.20% [0.07% to 0.45%]. The proliferation rate was significantly increased in AAC (8.0% [4.0% to 17.0%], P < 0.001) and ACC (14% [7.5% to 26.5%], P = 0.001) compared with control samples (1.0% [1.0% to 3.0%]). Strong HIF-1alpha staining was observed in 57% of AAC, in 100% of ACC and in 44% of control specimens (P < 0.001). Intense HIF-1alpha expression was associated with increased cell proliferation (P = 0.002).

CONCLUSION

Cell proliferation and apoptosis were increased in AAC and ACC, as compared with normal gallbladders. Expression of HIF-1alpha was lower in AAC than in ACC.

Continuous retention suture for the management of open abdomen: a high rate of delayed fascial closure

BACKGROUND AND AIMS

Open abdomen is most often a consequence of damage control surgery, abdominal decompression or intra-abdominal infections. Ventral hernia after unsuccessful closure of open abdomen causes marked disability to the patient. Several methods for delayed fascial closure have been developed. Patients treated with continuous retention suture were evaluated to find out how often fascial closure was achieved, and what complications were related to the technique.

METHOD

A retrospective analysis of 16 open abdomen patients treated with continuous retention suture.

RESULTS

The most common cause of open abdomen was abdominal infection. Complete fascial closure was achieved in nine of the eleven surviving patients. Closure failed in one patient. Partial closure was also achieved in one patient. The median time between leaving the abdomen open and starting the process of closure was twelve days. The longest period of open abdomen before successful fascial closure was 29 days. Five patients died before the process of closure was complete.

CONCLUSION

Delayed fascial closure can be accomplished by using the retention suture method described here.

Tight junction proteins in gallbladder epithelium: different expression in acute acalculous and calculous cholecystitis

There is a paucity of information of tight junction (TJ) proteins in gallbladder epithelium, and disturbances in the structure of these proteins may play a role in the pathogenesis of acute acalculous cholecystitis (AAC) and acute calculous cholecystitis (ACC). Using immunohistochemistry, we investigated the expression of TJ proteins claudin-1, -2, -3, and -4, occludin, zonula occludens (ZO-1), and E-cadherin in 9 normal gallbladders, 30 gallbladders with AAC, and 21 gallbladders with ACC. The number of positive epithelial and endothelial cells and the intensity of the immunoreaction were determined. Membrane-bound and cytoplasmic immunoreactivities were separately assessed. We found that TJ proteins were uniformly expressed in normal gallbladder epithelium, with the exception of claudin-2, which was present in less than half of the cells. In AAC, expression of cytoplasmic occludin and claudin-1 were decreased, as compared with normal gallbladder. In ACC, expression of claudin-2 was increased, and expression of claudin-1, -3, and -4, occludin, and ZO-1 were decreased, as compared with normal gallbladder or AAC. We conclude that there are significant differences in expression of TJ proteins in AAC and ACC, supporting the idea that AAC represents a manifestation of systemic inflammatory disease, whereas ACC is a local inflammatory and often infectious disease.

Organ system dysfunction following open cholecystectomy for acute acalculous cholecystitis in critically ill patients

BACKGROUND

Acute acalculous cholecystitis (AAC) refers to cholecystitis without gallstones and is a serious complication of critical illness. We describe the time course of organ system dysfunction associated with cholecystectomy in critically ill patients with AAC.

METHODS

The data of all intensive care unit (ICU) patients who had operatively confirmed AAC during their ICU stay between 2003 and 2004 were analyzed. Patients who also had other intra-abdominal pathologies were excluded. The Sequential Organ Failure Assessment (SOFA) scores were recorded 3 days before, on the day of operation and on the first, second, third and seventh post-operative day after cholecystectomy. The impact of open cholecystectomy on organ dysfunction was evaluated on the basis of the change in the total and individual organ SOFA scores.

RESULTS

Twenty-four patients underwent open cholecystectomy for AAC with no other intra-abdominal pathology. Sepsis was the most common admission diagnosis, followed by cardiovascular surgery. The mean (standard deviation, SD) Acute Physiology and Chronic Health Evaluation (APACHE II), Simplified Acute Physiology Score (SAPS) II and SOFA scores on admission were 24.7 (5.8), 44.3 (12.3) and 9.4 (3.2), respectively. The median (25th, 75th percentiles) total SOFA score 3 days before cholecystectomy was 7.5 (1.3, 8.0), which increased to 10.5 (8.3, 13.0) (P < 0.0001) by the day of cholecystectomy, indicating developing multiorgan dysfunction. After the operation, the score decreased to 5.5 (3.3, 10.8) (P = 0.004) by the seventh post-operative day. The change was most obvious in cardiovascular and respiratory SOFA scores.

CONCLUSIONS

AAC is associated with multiorgan dysfunction in critically ill patients. Open cholecystectomy seems to alter the course of multiorgan dysfunction in these patients.

Staged endovascular stent-grafting and surgical treatment of a secondary aortoduodenal fistula

Secondary aortoenteric fistula is a dramatic, rather infrequent late complication occurring mostly after abdominal aortic surgery. Currently, graft excision and in situ bypass is considered the treatment of choice, but it is associated with significant mortality and morbidity. Herein, we describe the case of a secondary aortoduodenal fistula treated by staged endovascular stent-grafting and surgical closure of the fistula. Forty days after stent-grafting, Tc-99m-HMPAO labelled leukocyte scanning failed to identify leukocyte infiltration of the graft and there were no clinical signs of infection. At 8-month follow up, the patient was asymptomatic.

Histopathology of acute acalculous cholecystitis in critically ill patients

AIMS

To illustrate the histopathological features of acute acalculous cholecystitis (AAC) of critically ill patients and to compare them with those of acute calculous cholecystitis (ACC) and normal gallbladders.

METHODS AND RESULTS

We studied 34 gallbladders with AAC and compared them with 28 cases of ACC and 14 normal gallbladders. Histological features were systematically evaluated. Typical features in AAC were bile infiltration, leucocyte margination of blood vessels and lymphatic dilation. Bile infiltration in the gallbladder wall was more common and extended wider and deeper into the muscle layer in AAC compared with ACC. Epithelial degeneration and defects and widespread occurrence of inflammatory cells were typical features in ACC. Necrosis in the muscle layer was also more common and extended wider and deeper in ACC. There were no differences in the occurrence of capillary thromboses, lymphatic follicles or Rokitansky-Aschoff sinuses between the AAC and ACC samples.

CONCLUSIONS

There are characteristic differences in histopathology between AAC and ACC, although due to overlap, none appeared to be specific as such for either condition. These results suggest that AAC is largely a manifestation of systemic critical illness, whereas ACC is a local disease of the gallbladder.

Effect of jaundice and its resolution on wound re-epithelization, skin collagen synthesis, and serum collagen propeptide levels in patients with neoplastic pancreaticobiliary obstruction

BACKGROUND

Wound and anastomotic healing is considered to be delayed in patients with obstructive jaundice. The study was designed to find out whether the healing of experimental suction blister wounds, skin collagen synthesis, and serum procollagen levels are affected by obstructive jaundice, and if biliary drainage may cause any alterations in these processes.

PATIENTS AND METHODS

Suction blisters were induced on 24 patients with obstructive jaundice caused by neoplastic pancreaticobiliary obstruction and 17 control patients with the corresponding condition without jaundice, to compare healing parameters and collagen synthesis between the groups. A second set of suction blisters were induced on 13 formerly jaundiced patients after the resolution of jaundice and on 14 control patients, to find out whether drainage or time modifies healing or collagen synthesis. By using this model, it is possible to evaluate the re-epithelization and inflammation on wound healing and to assess the baseline skin collagen synthesis. The healing of suction blisters was followed up by measuring water evaporation and blood flow in the wound. Blister fluids and serum samples were collected to study collagen propeptides.

RESULTS

Healing of the blister wound was unaffected by obstructive jaundice. Drainage had no effect on healing. The baseline synthesis of type I and type III collagen in the skin was decreased in jaundiced patients. Biliary drainage improved the synthesis. Serum type III procollagen propeptide levels were elevated in jaundiced patients, but began to normalize after drainage.

CONCLUSION

Healing of an experimental blister wound is not disturbed by obstructive jaundice. The decreased baseline skin collagen synthesis is partly restored by the resolution of jaundice. The results indicate that cell protein synthesis is disturbed earlier than cell dynamics in obstructive jaundice. The elevated serum PIIINP levels, which are most likely to be related to early fibrosis in liver, decreased after drainage.

The quality of life of gastroesophageal reflux disease patients waiting for an antireflux operation

BACKGROUND

The purpose of this trial was to measure the health-related quality of life (HRQL) of gastroesophageal reflux disease (GERD) patients waiting for an antireflux operation.

METHODS

A total of 120 patients waiting for a laparoscopic fundoplication were sent questionnaires measuring their symptoms and quality of life.

RESULTS

Ninety-five of the patients still needing an operation returned the questionaires and were included in the analysis. Thirty-one of 84 patients (37%) felt that the symptoms had worsened, and 51/90 (57%) were unsatisfied. Thirty percent suffered from throat or airway infections, 25% from swallowing difficulties, 48% from retrosternal pain, and 18% had asthma. The mean GERD HRQL score (0-45) was 21.7 (95% confidence interval, 19.7-23.7). Short Form-36 scores of this population were significantly worse when compared to patients with inguinal hernia or moderate asthma.

CONCLUSIONS

Patients waiting for a fundoplication seem to have a significantly decreased health-related quality of life due to poor symptom control regardless of continuous medical treatment.

Immunohistological distribution of the tight junction components ZO-1 and occludin in regenerating human epidermis

BACKGROUND

Molecular characterization of tight junction proteins during the past few years has provided novel methods for studying these specialized junctions. Tight junctions have recently been characterized in the granular cell layer of human epidermis, and the role of these junctions in the epidermal barrier is now being re-evaluated.

OBJECTIVES

To investigate the expression of tight junction components during the re-epithelialization of suction blisters and the regeneration of the corneal layer after tape stripping.

METHODS

Suction blisters were induced in eight healthy volunteers, and skin biopsies were taken 4 or 6 days afterwards. The restoration of epidermal barrier function was evaluated by measuring water evaporation (WE) from the wound area. Tape stripping was performed on three volunteers to remove the corneal layer. The tissues were immunolabelled using indirect immunofluorescence or the avidin-biotin method.

RESULTS

Prior to the biopsies, WE from the blister wounds was markedly elevated in comparison with normal skin. In the epidermis surrounding the blister, occludin and ZO-1 were expressed in the granular cell layer only. In the hyperproliferative zone adjacent to the border of the blister, the expression of ZO-1 was redistributed into several spinous cell layers, while occludin expression was restricted to the upper epidermis. In the leading edge of migrating keratinocytes, both proteins were expressed exclusively in the most superficial layer of keratinocytes. Double labelling for ZO-1 and involucrin showed expression of both proteins in the same layers of hyperproliferative keratinocytes, while the expression patterns were clearly different in the migrating keratinocytes.

CONCLUSIONS

Tight junctions of regenerating epidermis may provide a functional barrier prior to regeneration of the corneal layer.

Microcirculatory response of skin to benzoic acid and methyl nicotinate in patients with diabetes

AIMS

In view of the relationship between microvascular pathology and organ complications in diabetes mellitus, the aim of the present study was to examine the microvascular response of upper arm skin to non-immunological contact irritants in 17 insulin-dependent diabetic patients and 11 non-diabetic controls.

METHODS

Non-immunological contact urticaria, an inflammatory reaction mediated in a unique way, not previously studied in diabetic patients, was examined. The test agents were benzoic acid and methyl nicotinate. The intensity of the reactions was measured using laser-Doppler flowmetry and colorimetry. The patients were divided into two groups, depending on whether they had had diabetes for less or more than 10 years.

RESULTS

There were no differences in the maximal blood flow responses between the groups, but the diabetic patients showed increased blood flow responses to the lowest irritant concentrations compared to the controls. The reactions in the two groups of diabetic patients were similar.

CONCLUSIONS

The present study suggests that the microvascular reactivity of diabetic skin to non-immunological contact irritants is increased.

Delayed restoration of epidermal barrier function after suction blister injury in patients with diabetes mellitus

AIMS

Diabetes mellitus is a risk factor for compromised wound healing. The present study examines the restoration of the epidermal barrier function using the suction blister wound model.

METHODS

The healing process was evaluated over time by measuring water evaporation (WE) and blood flow (BF) in the wound area. Seventeen Type 1 diabetic males and 11 non-diabetic control males were studied.

RESULTS

At the onset, the WE of diabetic patients was 116 +/- 11 g x m(-2) x h(-1) and that of controls 95 +/- 13 g x m(-2) x h(-1) (P < 0.001). On the second day, the WE of diabetic patients was 90 +/- 21 g x m(-2) x h(-1) and that of controls 60 +/- 24 g x m(-2) x h(-1) (P < 0.02). The most profound difference was encountered during the fourth day, when the WE of diabetic patients was 40 +/- 17 g x m(-2) x h(-1) and that of controls 14 +/- 8 g x m(-2) x h(-1) (P < 0.001). The value recorded on the fourth day was 37% of the onset value in diabetic patients and 16% in controls (P < 0.001). Eight days after wounding the values were close to that of normal skin in both diabetic and control subjects. At the onset, the BF was 93 +/- 20 (arbitrary units) in diabetic men and 112 +/- 18 in controls (P = 0.02). On the second, fourth and eighth day there was no significant differences.

CONCLUSIONS

The results suggest that restoration of the epidermal barrier function is delayed in the patients with diabetes. There were also a trend toward an initially weaker inflammatory response.

Effects of PUVA and UVB treatments on restoration of epidermal barrier function and vascular response after suction blister injury in human skin in vivo

PUVA and UVB phototherapies are used in the treatment of psoriasis and other inflammatory skin diseases. Ultraviolet radiation causes inflammation and modulates cell kinetics in the skin. PUVA also has an inhibitory effect on skin DNA synthesis. In this study, the effects of PUVA and UVB treatments on epidermal would healing were examined using the suction blister wound model. The healing of the wound was studied indirectly by measuring water evaporation and blood flow in the wound area. On the fourth day, water evaporation was more abundant in PUVA-treated patients (42 +/- 5 g/m2h) than in UVB treated (36 +/- 4 g/m2h) or control patients (27 +/- 3 g/m2h) (analysis of variance, the least significant difference test at a level of 0.05). The P value for the difference of means between the PUVA and control groups was 0.014. Blood flow was also more abundant during the fourth (PUVA 162 +/- 11 arbitrary units, UVB 122 +/- 10, controls 115 +/- 15) and sixth (PUVA 108 +/- 18, UVB 73 +/- 17, controls 57 +/- 13) day in PUVA treated patients (analysis of variance, the least significant difference test at a level of 0.05). The results suggest that PUVA treatment decreases the restoration of the epidermal barrier function. The PUVA-treated patients also showed a more intense and prolonged vascular response that may be due to PUVA-related inflammation.

Expression of cytokeratins in regenerating human epidermis

The expression of cytokeratin polypeptides in regenerating human epidermis was immunohistochemically examined during re-epithelization of suction blisters. The regenerating basal and suprabasal epidermis expressed keratin polypeptides K13, K14, K16 and K18, which are not present in normal suprabasal epidermis. On the contrary, K10, a normal constituent of terminally differentiated keratinocytes, was lacking from the epidermis until the ninth day of re-epithelization. The findings indicate changes similar to other hyperproliferative states (expression of K16), basal-like features (expression of K14), or properties reminiscent of fetal skin (K13 and K18) in the newly formed epidermis. Monoclonal antibodies for cytokeratins and a technique using suction blisters seemed to be a suitable methodology for the study of epidermal regeneration in normal skin. The technique may also have advantages in the investigation of keratin expression in diseased skin.

Comparison of the effect of hydrocortisone, hydrocortisone-17-butyrate and betamethasone on collagen synthesis in human skin in vivo

It has been shown previously that topical corticosteroid treatment decreases collagen synthesis in human skin in vivo and that the adverse effects are due to reduced collagen synthesis. The aim of the present study was to evaluate the effect of hydrocortisone, hydrocortisone-17-butyrate and betamethasone on collagen synthesis in human skin in vivo. Fourteen healthy male volunteers applied hydrocortisone, hydrocortisone-17-butyrate, betamethasone and vehicle twice a day for one week to four separate areas marked on their abdominal skin. The collagen synthesis rate in the skin was measured by assaying collagen propeptides from the suction blisters induced on the treated areas. Aminoterminal propeptide of type I procollagen (PINP) and aminoterminal propeptide of type III procollagen (PIIINP) were measured from skin blister fluid using radioimmunoassays. Skin thickness was measured with ultrasound. Hydrocortisone decreased the two propeptides studied in the suction blister fluids less than did hydrocortisone-17-butyrate and betamethasone, but the interindividual variation was great. Hydrocortisone-17-butyrate and betamethasone had almost similar decreasing effects on the propeptides in the suction blister fluid. Hydrocortisone decreased the concentrations of PINP and PIIINP by about 35%. In some subjects (4/14) the decline of the collagen propeptide levels was over 50%. The decline in the concentration of PINP was 63% by hydrocortisone-17-butyrate and 69% by betamethasone, while the decrease in PIIINP was 55% by hydrocortisone-17-butyrate and 62% by betamethasone. None of the treatments had any effect on skin thickness within one week. In conclusion, it seems that hydrocortisone is less atrophogenic than hydrocortisone-17-butyrate and betamethasone, as shown by radioimmunoassays for collagen propeptides. The order of inhibitory potency of the three glucocorticoids on collagen synthesis was hydrocortisone < hydrocortisone-17-butyrate < betamethasone. Thus, assay of collagen propeptides from suction blisters can be used to screen various steroids with respect to their action on collagen synthesis.

Increased collagen synthesis in psoriasis in vivo

Psoriasis is an inflammatory skin disease of unknown a etiology which also involves changes in dermal elements. Previous in vitro studies have shown an increased collagen synthesis rate in cultured fibroblasts. In this study collagen synthesis was studied in vivo in the uninvolved skin of psoriatic patients using a newly developed method in which collagen propeptides were measured in suction blister fluid. Both type I and type III collagen synthesis rates, as measured in terms of the carboxyterminal propeptide of type I procollagen (PICP) and the aminoterminal propeptide of type III procollagen (PIIINP), were increased about two-fold in uninvolved psoriatic skin as compared with controls, the mean level of PICP being 870 and 457 micrograms, respectively (P < 0.001), and of PIIINP being 294 and 124 micrograms, respectively (P < 0.01). The increased collagen synthesis rate was also confirmed by in situ hybridization using specific probes. Collagen mRNAs were found to be particularly abundant in psoriatic patients, who also demonstrated a high collagen synthesis rate when assayed by measuring collagen propeptides. The increased rate of collagen synthesis in the uninvolved psoriatic skin seemed not to be related to the severity of the disease or to various treatments such as UVB, PUVA, retinoids or cytostatic drugs, but seemed more likely to be due to the psoriasis itself. Interestingly, skin thickness was not increased in the patients with psoriasis, even though collagen synthesis was markedly elevated, perhaps suggesting that in psoriasis the turnover rate of collagen is enhanced.

Topical mometasone furoate and betamethasone-17-valerate decrease collagen synthesis to a similar extent in human skin in vivo

Topical corticosteroids are used extensively to treat inflammatory skin diseases. Long-term use, however, may be associated with adverse effects such as skin atrophy. New steroids have been developed with the objective of increasing efficacy and reducing the incidence of adverse effects. Mometasone furoate (MMF) is one of these new derivatives. The aim of our study was to compare the effects of MMF and betamethasone-17-valerate (BM-17-valerate) on collagen synthesis in human skin in vivo. Fifteen healthy male volunteers applied MMF, BM-17-valerate and vehicle for 1 week to different areas of abdominal skin. Suction blisters were raised on these areas, and a control site, and procollagen propeptide (PICP, PINP, PIIINP) levels in the suction blister fluid were measured by radioimmunoassay. Skin thickness was measured ultrasonically by Dermascan A at the end of the treatment period. The levels of the three propeptides in suction blister fluid were reduced to similar extent by MMF and BM-17-valerate. The 1-week treatment period had no detectable influence on skin thickness. We conclude that MMF and BM-17-valerate decrease collagen synthesis to the same extent in human skin in vivo.

UV irradiation induces the expression of gelatinases in human skin in vivo

UV irradiation results in marked changes in skin connective tissue, such as degeneration of collagen, and abnormal elastosis. The mechanism of connective tissue damage by UV has not been clarified in detail. In the present study the mechanism of actinic damage was studied by assaying gelatinases, 72-kDa (MMP-2) and 92-kDa (MMP-9), from suction blister fluids induced on patients who had received either UVB or PUVA treatments. The results indicate that both UVB and PUVA increase the levels of gelatinases in human skin. By in situ hybridization, it was also possible to show that UV irradiation induced increased levels of gelatinase mRNAs in fibroblasts. Furthermore, in samples from severe actinic damage, gelatinase mRNAs were abundantly present, suggesting that gelatinases may contribute to photodamage.