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To study the role of the skin in differential calcium metabolism in White Leghorn chickens, we compared the composition of suction blister fluid (SBF) collected from cutaneous blisters with blood and serum in female and male animals in various physiological states. As an estimate for interstitial fluid (IF), SBF was used as a determinant of local cutaneous metabolism. Sample collection was carried out under ketamine-xylazine anesthesia. Eight chickens of both sexes were raised freely in similar environmental conditions and fed with similar food during their growth from juvenile to sexually mature and fully adult state. SBF, blood and serum were examined for concentrations of ionized Ca2+, Na+ and K+ with ion-selective electrodes (ISEs), and osmolalities by freezing point osmometry. pH and total protein content were also assessed. Our results showed that SBF of chickens is calcium-poor at the juvenile state and that it draws more Ca2+ in adult males than laying females of the same age. Interestingly, Ca2+ accumulation was observed also in females after laying had ceased. There was a positive correlation between blood and SBF Ca2+ in females but a negative one in males. In general, it was found that SBF of chickens was rich in Na+ and K+, was hypertonic compared to serum at the juvenile state and had a protein content of 36-47% of that in serum. Different from mammals, SBF in adult chickens was alkaline with the mean values of 8.7+/-0.14 in females and 8.8+/-0.06 in males. Age- and sex-related variability in cutaneous Ca2+ concentrations in chickens, and the differences of SBF composition between that of mammals point to a novel role of skin functions in avians. Possible functions of the skin as a dynamic calcium source balancing the free circulating Ca2+ levels and, also, as an excretory organ for Ca2+ are discussed.

Objective: To investigate infant feeding patterns during the first 2 y and their relation to sociodemographic factors., Design: A population-based cohort study., Setting: Oulu and Tampere University Hospital district areas 1996-1999, Finland., Subjects and Methods: All newborn infants (n=675) with increased genetic risk for type I diabetes were invited to the study in 1996-1997. Of these, 429 (64%) completed the dietary follow-up form by the time they reached 2 y of age., Results: The median duration of exclusive breastfeeding (BF) was 1.8 months (range 0-6 months) and that of total BF 7.0 months (0.3-25 months). Among the infants 20% were exclusively breastfed at least 4 months (recommendation 4-6 months). Infants were introduced to infant formula at the median age of 1.8 months (range 0-25 months) and other supplementary foods at the median age of 3.5 months (1-6 months). Infant's ponderal index at birth was inversely associated with the duration of total BF. The age of introduction of supplementary foods correlated positively with the duration of total BF. Longer parental education and increased maternal age were associated with a longer duration of BF and older age at introduction of supplementary foods. Infant formula and other supplementary foods were added earlier to the diet of the boys than that of the girls., Conclusion: Duration of breastfeeding in Finland is shorter than recommended. Compliance with the current recommendations on the timing of introduction of first supplementary food and dairy products is relatively poor. The diet during infancy seems to be conspicuously influenced by the duration of parental education, maternal age and the sex of the infant.

Background and Purpose: To measure local changes of collagen metabolism in irradiated breast skin and systemic changes in serum during and after radiotherapy and correlate these changes with skin thickness, erythema and palpable subcutaneous induration., Patients and Methods: Aminoterminal propeptides of type I and type III procollagens (PINP and PIIINP, respectively) were measured from skin suction blister fluid (SBF) in 21 breast cancer patients with breast conserving surgery and conventionally fractionated radiotherapy (RT) to a total dose of 50Gy. Suction blisters were induced in the operated and contralateral breast skin before RT, at 2.5 weeks, at the end of RT, and at 1, 4, 7, 12 and 24 months post-treatment. Blood samples for serum were taken simultaneously with SBF induction. Skin thickness of the suction blister sites was measured with a high-frequency ultrasound device. The investigated sites were scored for erythema at the end of RT and palpable subcutaneous induration at 1 and 2 years post-treatment., Results: In SBF the mean levels of PINP and PIIINP of the operated breast before RT were about 3-4 times higher than those in the contralateral breast due to the operation-related wound healing. The synthesis of PINP in irradiated breast after RT increased 7.7-fold (P < 0.001) 4 months post-irradiation. The PIIINP synthesis was at maximum at 1 month post-irradiation (P < 0.001). Both synthesis stayed elevated until 2 years. The level of PINP correlated significantly with the palpable skin induration at 1 and 2 years (P = 0.038 and P = 0.003, respectively). The skin thickness of the irradiated breast was highest at 4 months post-treatment and significantly elevated until 1 year. The skin thickness correlated with the PINP level until 7 months and with PIIINP between 4 and 18 months. The PINP/PIIINP ratio reached the maximum at 4 months and stayed elevated until 2 years. No change in mean serum level of PINP was found during or after RT., Conclusions: We demonstrated a maximum and elevated levels for PINP and PIIINP skin collagen metabolism determined from SBF during the 2 years' follow-up. Elevated levels of PINP and PIIINP correlated with the thickening of the skin and subcutaneous induration but not with erythema.

Background/aims: Open chamber systems for measuring transepidermal water loss (TEWL) have limitations related to ambient and body-induced airflows near the probe, probe size, measurement sites and angles, and measurement range. The aim of the present investigation was to develop a closed chamber system for the TEWL measurement without significant blocking of normal evaporation through the skin. Additionally, in order to use the evaporimeter to measure evaporation rates through other biological and non-biological specimens and in the field applications, a small portable, battery-operated device was a design criteria., Methods: A closed unventilated chamber (inner volume 2.0 cm(3) was constructed. For the skin measurement, the chamber with one side open (open surface area 1.0 cm(2) is placed on the skin. The skin application time was investigated at low and high evaporation rates in order to assess the blocking effect of the chamber on normal evaporation. From the rising linear part of the relative humidity (RH) in the chamber the slope was registered. The slope was calibrated into a TEWL value by evaporating water at different temperatures and measuring the water loss of heated samples with a laboratory scale. The closed chamber evaporation technique was compared with a conventional evaporimeter based on an open chamber method (DermaLab), Cortex Technology, Hadsund, Denmark). The reproducibility of the closed chamber method was measured with the water samples and with volar forearm and palm of the hand in 10 healthy volunteers., Results: The skin application time varied between 7 and 9 s and the linear slope region between 3 and 5 s at the evaporation rates of 3-220 g/m(2) h. A correlation coefficient between the TEWL value from the closed chamber measurements and the readings of the laboratory scale was 0.99 (P < 0.001). The reproducibility of the evaporation measurements with the water samples was 4.0% at the evaporation rate of 40 g/m(2) h. A correlation coefficient of the TEWL values between the closed chamber and open chamber measurements was 0.99 (P < 0.001) in the range where the response of a conventional evaporimeter was linear (until 120 g/m(2)h. With volar forearm and palm of the hand of 10 healthy volunteers the reproducibility of the measurements was 8.0 and 10.1%., Conclusion: The closed chamber technique solves the drawbacks related to open chamber evaporimeters. Especially, it extends the measurement range to high evaporation rates and TEWL measurements can be performed practically at any anatomical sites and measurement angle. By the use of a closed chamber the disturbance related to external or body-induced air flows on the measurement can be avoided.

Background: Glucocorticoids have been shown to downregulate collagen synthesis in human skin in vivo, thereby contributing to skin atrophy., Objectives: To compare the effects of continuous and intermittent use of topical hydrocortisone on skin collagen synthesis and, furthermore, to elucidate the mechanism of collagen synthesis reduction induced by hydrocortisone., Methods: Collagen propeptides reflecting the synthesis rate of type I and III collagens were studied from suction blister fluids in nine healthy subjects after 3 weeks of continuous (twice daily) or intermittent (on three consecutive days weekly) topical hydrocortisone treatment and 2 weeks after the termination of treatment. Type I collagen mRNA was studied in the same subjects from skin biopsies by using in situ hybridization (ISH) after 3 weeks of treatment., Results: Three weeks of continuous treatment decreased the types I and III collagen propeptides in suction blister fluid by 89% and 82%, respectively, while intermittent treatment resulted in a corresponding decrease of 53% and 50%. ISH studies from skin biopsies showed type I collagen mRNA to be markedly reduced in fibroblasts after continuous and intermittent steroid treatment. After a 2-week drug-free interval, the synthesis rate was completely restored in both areas, and some subjects even showed upregulation of synthesis in previously steroid-treated skin., Conclusions: Continuous hydrocortisone for 3 weeks markedly decreases collagen propeptides and corresponding mRNA in human skin. Intermittent hydrocortisone has a less marked effect on the collagen synthesis rate.

The aim of this study was to investigate the suitability and effectiveness of heliotherapy in moderate or severe atopic dermatitis in adults in the Canary Islands. A total of 216 patients participated on 6 different 2- or 3-week heliotherapy trips. Using the Severity Scoring of Atopic Dermatitis Index (SCORAD), the severity of atopic dermatitis was assessed prior to the start of heliotherapy, after 2 weeks and then 3 months after the end of heliotherapy. A quality-of-life questionnaire was later mailed to all participants. The mean SCORAD index was reduced by 70% after 2 weeks of heliotherapy and was still 45% lower 3 months after therapy (P<0.0001). At 3 months, the use of topical steroids was still significantly reduced (P<0.0001), whereas there was no significant (P=0.1166) change in the consumption of emollients. The quality of life of patients was improved and their self-treatment and working capacity was increased. As the longer 3-week period provided no significant additional advantage over a 2-week period, 2 weeks of heliotherapy can be considered optimal. In conclusion, heliotherapy is an effective and valuable therapeutic adjunct, especially in adults with severe atopic dermatitis.

Circulating C-terminal propeptide of type I procollagen (PICP), mostly originating from bone, is mainly cleared by mannose receptors (MRs) in liver endothelial cells (LECs). We hypothesized that skin macrophage MRs could also play a role in local (in situ) clearance of PICP originating from skin type I procollagen synthesis. We tested this hypothesis in a male subject with a genetic systemic clearance defect, apparently due to an abnormality in MR function in LECs (or in PICP structure). Since skin macrophages may express the same MRs as LECs do, the genetic defect could affect them as well; hence, if elevated PICP concentrations even in skin interstitial fluid (IF) were found in our subject, it would suggest a role for local MR-mediated PICP clearance in skin. Since glucocorticoids (GCs) upregulate MRs in vitro, we measured the effect of topical GC on suction blister fluid (SBF)-PICP of the test person as compared with normal subjects. SBF-PICP was elevated in the case, which was consistent with the hypothesis. Furthermore, the GC-induced decrease was accentuated. The results suggest that skin macrophage MRs can have a role in skin PICP clearance in situ.

Dietary recommendations for children with type 1 diabetes mellitus (DM) are in line with the recommendations for the general population and applicable to the whole family. We review what is known about the food habits of non-diabetic family members and present original data on dietary changes in families with a child with DM. Some studies suggest that family members eat mostly the same food as the affected child. In a Finnish study of siblings of children with DM, favourable changes were observed after diagnosis in the type of milk and fat used. In a study of young children with DM, family members increased their consumption of skim milk, low-fat cheese and low-fat cold meat cuts. The consumption frequencies of fruit and vegetables increased. In conclusion, family members of a child with DM are willing to change their food habits towards the recommended diet. Dietary advice should be directed to the whole family from the very beginning.

Retinoids and glucocorticoids are known to have a potential to modulate the expression of transforming growth factor-beta (TGF-beta). We investigated the effect of oral isotretinoin (13-cis-retinoic acid) on the expression of two distinct isoforms of TGF-beta, TGF-beta1 and TGF-beta2, in suction blister fluid and serum in acne patients. We also investigated the effect of topical glucocorticoid (betamethasone-17-valerate) and age on suction blister fluid TGF-beta1 in healthy volunteers. Six weeks of isotretinoin treatment caused a statistically significant 19% increase in suction blister fluid TGF-beta1. The suction blister fluid TGF-beta2 level remained below the sensitivity level of the immunoassay in many cases. Isotretinoin did not affect the serum TGF-beta1 or TGF-beta2 level. Betamethasone-17-valerate pretreatment for 3 days twice a day caused a statistically significant 17% decrease in suction blister fluid TGF-beta1. The active form of TGF-beta1 represented 5% of the total TGF-beta1 in suction blister fluid. Our diffusion calculations suggest that all TGF-beta1 and TGF-beta2 detected in suction blister fluid have diffused from systemic circulation. The increase in suction blister fluid TGF-beta1 after isotretinoin treatment seems to be of local origin, while the decrease in suction blister fluid TGF-beta1 after glucocorticoid pretreatment seems to be due to glucocorticoid-induced vasoconstriction resulting in decreased diffusion of TGF-beta1 from the circulation. Modulation of local interstitial fluid TGF-beta1 concentration may be one mechanism by which isotretinoin and glucocorticoids mediate their effects in skin., (Copyright 2000 S. Karger AG, Basel)

Objective: To evaluate whether the increased risk of type 1 diabetes conferred by an early introduction of cow's milk supplements can be mediated by accelerated growth in formula-fed infants., Research Design and Methods: All children < or = 14 years of age who were diagnosed with type 1 diabetes from September 1986 to April 1989 were invited to participate in the study. Birth date- and sex-matched control children were randomly selected from the Finnish Population Registry. At least three weight measurements from the first year of life were obtained for 435 full-term diabetic subjects and 386 control subjects from well-baby clinics and school health care units., Results: Increase in body weight was greater in the diabetic girls than in the control girls, and the difference increased from 111 g (95% CI 0-218, P = 0.04) at 1 month of age to 286 g (95% CI 123-450, P = 0.0006) at 7 months. For boys, the difference in weight between the diabetic subjects and the control subjects remained stable during infancy (difference 95 g, 95% CI-2-205, P = 0.09). Increased weight was associated on average with a 1.5-fold risk of type 1 diabetes. Early introduction of formula feeding (< 3 vs. > or = 3 months) was also associated with an increased risk of type 1 diabetes after adjustment for the individual weight gain curve (adjusted odds ratio 1.53, 95% CI 1.1-2.2). No evidence for interaction was observed., Conclusions: These observations indicate that an early exposure to cow's milk formula-feeding and rapid growth in infancy are independent risk factors of childhood type 1 diabetes.

We investigated the effect of the potentially carcinogenic psoralen plus UVA radiation (PUVA) therapy on the expression of p53 in skin of psoriatic patients. p53 antibodies DO7 and Pab240, antibodies against PCNA and Ki67 and the avidin-biotin immunoperoxidase complex method were used in the immunohistochemical staining of biopsy samples from non-lesional and lesional skin of 23 patients who received either trioxsalen bath PUVA or oral 8-methoxypsoralen PUVA. Biopsies were taken before and after a PUVA course. A modest expression of p53 was seen in psoriatic lesions in 17/21 patients before any treatment, probably as a physiological reaction to the hyperproliferation. Both p53 and the proliferation markers Ki67 and PCNA followed the same pattern, being more frequent in psoriatic lesions than in non-lesional skin. Exposure to PUVA induced an increase in p53 expression in non-lesional skin in 14/19 patients, putatively as a response to DNA damage caused by PUVA. In psoriatic lesions about half of the patients showed increased and half decreased expression of p53. The latter finding might be explained by decreased proliferation activity of the healing epidermis. In conclusion, p53 nuclear positivity in non-lesional skin after PUVA treatment is likely to be induced by DNA damage caused by PUVA, while in psoriatic lesions it could be a result of the combined effect of decreasing epidermal proliferation and DNA-damage.

Life-saving mastectomy and radiation therapy are established in the treatment of early stage breast cancer. Angiosarcoma, i.e. malignant angioendothelioma, is a rare tumor which can develop after several years of such treatment. The number of post-operative and post-irradiation angiosarcomas has increased in recent years. We report four cases of angiosarcoma which occurred after treatment of breast cancer and review the literature. In two of these cases the angiosarcoma developed on the irradiated breast skin after partial mastectomy and radiation therapy, in the other two cases the angiosarcoma appeared on a chronically edematous arm after radical mastectomy and radiation therapy.

We conducted a randomized, double-blind, placebo-controlled trial to assess the atrophogenicity of tacrolimus ointment. In a combined group of atopic dermatitis patients (n = 14) and healthy volunteers (n = 12), 0.3% tacrolimus, 0.1% tacrolimus, betamethasone-valerate, and a vehicle control were applied in a randomized order to nonsymptomatic, 4 cm x 4 cm regions of abdominal skin. After 7 d of treatment under occlusion, the carboxy- and amino-terminal propeptides of procollagen I (PICP, PINP) and the amino-terminal propeptide of procollagen III (PIIINP) were measured from suction blister fluid with specific radioimmunoassays. In addition, ultrasound measurements of skin thickness were taken. Betamethasone-treated areas showed median PICP, PINP, and PIIINP concentrations of 17.0%, 17.6%, and 39.5% of the vehicle control at the end of the treatment period, respectively, whereas the 0.1% and 0.3% tacrolimus-treated areas showed median concentrations of approximately 100% of the vehicle control (p < 0.001). Betamethasone was also the only treatment to reduce skin thickness; the median decrease in skin thickness was 7.4% relative to 0.1% tacrolimus, 7.1% relative to 0.3% tacrolimus, and 8.8% relative to the vehicle control (p < 0.01). Results for atopic dermatitis patients and healthy volunteers were similar. These findings suggest that tacrolimus does not cause skin atrophy.

Fibrosis is a common side-effect of radiation therapy. As a complex network of cytokines and other mediators plays a central role in the process leading to fibrosis, we used an in vivo method to measure skin collagen synthesis, taking into account the physiological conditions. We determined suction blister (i.e. interstitial) fluid concentrations of types I and III procollagen propeptides, reflecting types I and III collagen synthesis, in irradiated and unirradiated skin of breast cancer patients 1-5 years after surgery and radiation therapy, hence using the patients as their own controls. The mean concentrations of the measured collagen markers were approximately two times higher in the irradiated skin than in the unirradiated contralateral breast skin. The difference slowly diminishes with time. These results indicate that abundant collagen synthesis in the irradiated skin continues several years after discontinuation of the radiation therapy, leading to fibrosis. The method outlined here offers a new in vivo perspective to study events leading to radiation fibrosis.

Background/aims: Types I and III collagen are the main fibrillar collagens in the skin. Marked changes occur in the biosynthesis of these proteins during treatment with various drugs, upon ageing and in several diseases. Since conventional methods of assessing these changes have several disadvantages, a new method for estimating collagen synthesis in human skin in vivo has recently been developed. In this method suction blisters are induced on intact, and treated or diseased skin and types I and III procollagen propeptides are measured radioimmunologically in suction blister fluid (SBF)., Conclusions: The concentrations of type I and III procollagen propeptides in SBF reflect the corresponding local ongoing skin collagen synthesis. This method offers a new sensitive tool for experimental and clinical dermatology for monitoring skin collagen synthesis. With this method it has been possible, for example, for the first time directly to show in vivo that glucocorticoids rapidly and dramatically decrease human skin collagen synthesis.

Tetracyclines are broad-spectrum bacteriostatic antimicrobials drugs, traditionally used in dermatology for the treatment of acne. Owing to their beneficial antiinflammatory properties, and the low risk and modest side effects associated with them, tetracyclines are also useful in treating several other skin diseases-either alone, or in combination regimens to reduce the intensity of the immunosuppressive effect.

Some alphaviruses, e.g. Sindbis, cause an acute febrile illness associated with papular rashes and arthralgia. The diagnosis is usually serological and, hence, the histopathology of the rashes has been poorly elucidated. We report on two patients with rapidly healing eruptions associated with Sindbis virus infection. The histopathology of the rashes showed large, pronounced lymphohistiocytic infiltrates with atypical lymphoid cells around the hair follicles, changes not usually seen in rapidly-healing dermatoses.

Acne fulminans is a rare, severe type of acne with unknown etiology. Ulcerative acne lesions, fever and musculoskeletal pain are typical symptoms. In addition, osteolytic or even destructive osteomyelitis-like bone lesions occur in many patients with acne fulminans. In the present study the degradation product (ICTP) of type I collagen, the most abundant collagen of the skeleton, was measured from the sera of patients suffering from acne fulminans. In 3 of 4 acne fulminans patients with active disease, the ICTP concentrations were clearly higher than the range of concentrations in age-matched controls. The mean concentration of ICTP in the acne fulminans patients was 17.6 +/- 6.0 micrograms/I, whereas the corresponding concentration in 6 patients with severe nodular acne was 6.9 +/- 2.1 micrograms/I. Increased uptake of radionuclide in bone scans was observed in all of the 4 patients with acne fulminans. The present results suggest that ICTP is increased in acne fulminans, due to the destruction of bone collagen matrix. ICTP could thus be used for monitoring the activity of acne fulminans affecting the skeleton.

Skin atrophy has been observed after prolonged use of inhaled corticosteroids. We therefore studied the effect of inhaled budesonide and nedocromil in patients with asthma on concentrations of procollagen propeptides in suction blister fluid reflecting skin collagen synthesis in vivo. Both types I and III procollagen propeptide concentrations decreased significantly after 6 wk of either 1,600 micro g/day (n=10) or 400 micro g/day (n=9) of inhaled budesonide but not in control subjects using inhaled nedocromil 16 mg/day (n=9). The reduction in mean propeptide concentrations ranged from 39 to 63%; the effects of the two budesonide doses did not differ significantly. Thus, even a low dose of inhaled corticosteroid represses skin collagen synthesis within a relatively short period.

In order to study the effects of repeated UVB exposures on the epidermal antioxidant defence system, we obtained epidermis samples from male volunteers who were exposed to chronic UVB irradiation. Chronic UVB irradiation was shown to be accompanied by induction of epidermal superoxide dismutase (SOD) activity in vivo, while the activities of the other antioxidant enzymes were not significantly changed. The repeated exposure of the epidermis to UVB irradiation was not accompanied by accumulation of products of lipid peroxidation reactions. As superoxide dismutase is of major importance in scavenging the reactive oxygen species, the UVB-induced changes in SOD activity might provide the epidermis a way of defending itself against the effects of chronic UVB irradiation.

Polyfunctional aziridine (PFA) is increasingly used as a water-based crosslinker in two-component paints, paint primers, lacquers, topcoats and other protective coatings. The crosslinker is made by reacting multifunctional acrylic monomer with a highly reactive aziridine compound. Respiratory allergy or hypersensitivity from PFA has not been reported previously. During 1978-1991 we came across nine cases with hypersensitivity from PFA: two had allergic contact dermatitis (ACD), four had occupational asthma and three had both of them. Five of the patients were parquet layers, two were fibreboard painters, one was a spray painter and one was a salesman of PFA products. ACD was diagnosed by positive allergic patch test reactions with PFA in a dilution series in petrolatum: 0.32%-0.5% gave a 2(+)-3+ allergic reaction in the five cases with ACD but 0.1% gave only a weak reaction in one case, whereas the methacrylate patch test series was negative. The diagnosis of seven cases of occupational asthma due to PFA hardener was based on symptoms related to exposure to PFA hardener at work, and on positive provocation tests with PFA hardener. One had an immediate type reaction, one a had a dual reaction, and the others had late reactions. The positive reactions with the PFA hardener and the negative reactions with the acrylate compounds indicate that PFA caused ACD which is different from the previous reports in which acrylates present as impurities in the PFA hardener caused the sensitization.(ABSTRACT TRUNCATED AT 250 WORDS)

The expression of two matrix metalloproteases (MMPs), 72 kDa gelatinase (MMP-2) and 92 kDa gelatinase (MMP-9), was studied in suction blister fluids and serum using a zymographic method. Both of the enzymes were detectable in blister fluid and serum, but their expression varied. The MMP-2 levels in serum were only about half of the levels in blister fluid, while the level of MMP-9 was about the same in both serum and blister fluid. The overall level of MMP-2 in serum was much lower than the level of MMP-9 which was possibly derived from inflammatory cells. In subjects aged from 20 to 86 years, no marked changes were seen in the serum or blister fluid gelatinases. Interestingly, body site affected the level of MMP-9. The lowest level was recorded in fluid from blisters on the lower leg, in which the level was only about 19% of the level in fluid from blisters on the abdomen. The levels of MMP-2 and MMP-9 were not decreased by pharmacological doses of systemic prednisone or isotretinoin, which indicates that systemic glucocorticoid or retinoid treatment does not affect the basal levels of MMP-2 and MMP-9.

The effects of systemic glucocorticoid and isotretinoin treatments on type I and type III collagen synthesis in intact skin were investigated by measuring the carboxyterminal and aminoterminal propeptides of type I procollagen, and the aminoterminal propeptide of type III procollagen, in suction blister fluid (SBF), in a study of 27 patients. All three parameters were significantly lower in the SBF of glucocorticoid-treated patients than in controls or patients undergoing treatment with isotretinoin, whereas the latter two groups did not differ significantly from each other. During glucocorticoid treatment, the concentrations of the procollagen propeptides were only about 20% of the corresponding control values, indicating that systemic therapy with prednisone at a dose of 0.48 mg/kg per day almost totally abolishes collagen synthesis in the skin. These results indicate that systemic glucocorticoid treatment suppresses the synthesis of both type I and type III collagen in the dermis, and suggest that many side-effects of these drugs, such as atrophy of the skin, are due to this inhibition. Systemic isotretinoin treatment did not stimulate skin collagen synthesis. Thus, its regenerative effect on connective tissue may be mediated by mechanisms other than direct stimulation of collagen synthesis.

The effect of aging, sex, skin location and a short whole body ultraviolet B (UVB) phototherapy on type I and type III skin collagen synthesis were studied by measuring carboxy- and aminoterminal propeptides of type I and aminoterminal propeptide of type III procollagens (PICP, PINP and PIIINP, respectively) in suction blister fluid (SBF). The concentrations of PICP and PIIINP correlated negatively with age in the material of 30 men and 27 women (age range 23-86 years, mean age 51 years). As the subjects were divided into 3 age groups (23-34, 35-54 and 55-86 years) and the mean concentrations of the procollagens were compared between the groups, the youngest age groups in men and in the whole material had significantly higher concentrations than the two older age groups. These results confirm the previous results, which have shown by other methods that skin collagen synthesis decreases during aging. SBF was also obtained from 4 different body regions (back, arm, abdomen and leg) of 5 young male subjects and from 2 different body regions (abdomen and thigh) of 9 older subjects. Wide individual range in the concentrations of PICP, PINP and PIIINP was noticed but, in general, none of the body regions seemed to have more excessive collagen synthesis than the other ones. SBF was further collected from abdominal skin of 8 young male dermatological patients receiving UVB phototherapy. When the concentrations of PICP and PIIINP in SBF obtained before the treatment, after the treatment and from the covered control area were compared no statistical differences were noted, suggesting that short UVB treatment has no effect on skin collagen synthesis in vivo.

Levels of interleukin 1 alpha (IL-1 alpha) were studied from blister fluids collected from 14 patients with various types of blistering diseases. In all the fluids, IL-1 alpha could be detected, the concentrations varying from 5 to 1730 pg/ml. For comparison IL-1 alpha was also assayed from suction blisters of 13 subjects; 8 atopic patients and 5 healthy controls. IL-1 alpha was also present in suction blisters in measurable quantities, suggesting that during suction IL-1 alpha is released into the blister cavity. Since IL-1 alpha has been shown to have marked effects on collagen metabolism, the marker of collagen synthesis (carboxyterminal propeptide of type I procollagen (PICP)) and gelatinase were assayed from the same samples. There was no apparent correlation between the levels of IL-1 alpha, PICP or gelatinase in blister fluids. The possible association of IL-1 alpha and collagen metabolism was further studied in experimental conditions. Topical glucocorticoid markedly decreased the level of PICP in suction blisters but did not have any significant effect on IL-1 alpha. UVB-radiation, on the other hand, caused increase in IL-1 alpha but did not have any profound effect on collagen metabolism. During the re-epithelialization of the blister floor the level of IL-1 alpha decreased markedly, and at the same time the expression of gelatinase was increased. The results indicate that IL-1 alpha is released in large quantities into blister fluid when using the suction blister model. However, no apparent correlation could be observed in healthy or diseased skin between the levels of IL-1 alpha, collagen synthesis marker or gelatinase.

Type IV collagenases have been shown to play an important role in tumor metastasis and wound healing. In the present study, we have demonstrated the presence of 72-kDa and 92-kDa forms of type IV collagenase in human skin by biochemical and in situ hybridization techniques. In situ hybridization allowed us to localize the 72-kDa form mostly to fibroblasts and the 92-kDa form to the epidermis and endothelial cells. The presence of type IV collagenase was confirmed by Western blotting. Enzyme activity was assayed in spontaneous blisters (18 subjects) and suction-induced blisters (29 subjects) by the zymography method, and by using type IV collagen as the substrate. Thus, it was possible to detect both the 92-kDa and 72-kDa forms in spontaneous and induced blisters. An especially high level of the 92-kDa enzyme was found in a bullous pemphigoid patient. Type IV collagenases were studied during re-epithelialization of the blister, using the suction-blister model. There was a marked induction of the 92-kDa type that was confirmed to be in the regenerating, migratory, epithelium by in situ hybridization studies. These results indicate that 92-kDa type IV collagenase may play an essential role in the normal physiology and integrity of the skin and may be an important regulator of re-epithelialization. It was also shown that potent topical glucocorticoid down-regulated the 92-kDa type collagenase, suggesting that glucocorticoids may have a beneficial role in some skin diseases by decreasing type IV collagenase activity and, thus, reducing tissue destruction.

In the present investigation, collagen synthesis and degradation were studied by measuring the carboxyterminal propeptide of type I procollagen (PICP), the aminoterminal propeptide of type III procollagen (PIIINP) and a type I collagen-specific degradation peptide (ICTP) in the sera of 43 male patients, treated for acne with isotretinoin or with tetracycline. The values were compared with those observed in 24 acne patients without treatment and in healthy controls. The treatment with isotretinoin did not seem to affect these parameters in a cross-sectional setting, whereas tetracycline treatment was associated with slightly decreased levels of ICTP. Since there were marked variations in the PICP, PIIINP and ICTP levels between individual subjects, a follow-up study, including male and female patients, others than in the first part of the study, was conducted. Two other biochemical markers of bone metabolism, osteocalcin, reflecting osteoblastic activity, and tartrate-resistant acid phosphatase (TRAP), reflecting osteoclastic activity, were also analyzed. In females, all these parameters were lower than in males. In addition, the changes in females were more pronounced; in particular, PIIINP and TRAP were significantly increased in females during retinoid treatment (p < 0.05 and p < 0.01, respectively). Importantly, no increase was found in the synthesis of type I collagen during retinoid treatment, suggesting that the commonly used retinoid dosages do not stimulate the synthesis of type I collagen in vivo.

Serum concentrations of the markers of collagen synthesis and degradation, collagen I propeptide (PICP), collagen III propeptide (PIIINP) and the cross-linked telopeptide of type I collagen (ICTP) were measured in young male dermatological patients and in control subjects. No significant differences were noted between patients suffering from atopic eczema (n = 24), other eczemas (n = 11), acne (n = 8), psoriasis (n = 7) or tinea (n = 9) and the control subjects (n = 24). In the total study population representing patients with common skin diseases and control subjects there was a significant correlation between the serum concentrations of PICP and PIIINP and between the concentrations of PICP and ICTP. This suggests that synthesis of type I and III collagens in vivo is coordinated and that the degradation and synthesis of type I collagen is balanced. These markers were also measured in older patients suffering from psoriasis, eczema and various connective tissue diseases. It was noted that the degree of skin involvement in these diseases was not related to the serum concentrations of the markers of collagen metabolism. The highest levels of PICP and PIIINP were observed in a patient with systemic mastocytosis (PICP 309 micrograms/l and PIIINP 8.0 micrograms/l). Increased levels of PIIINP were also found in patients with a high alcohol consumption. We have previously demonstrated that systemic glucocorticoids reduce collagen propeptide levels in serum. In the present study we also proved that systemic glucocorticoids have no effect on collagen degradation.(ABSTRACT TRUNCATED AT 250 WORDS)

The serum levels of muscle-specific serum carbonic anhydrase III (S-CAIII) and myoglobin (S-Myo) were analyzed in various male dermatological patients of the same age. The mean levels of S-CAIII and S-Myo were essentially similar in patients with acne, psoriasis vulgaris, atopic eczema and tinea, suggesting that common dermatological diseases do not affect the serum levels of the muscle markers. Increased levels of S-CAIII, which is specific for skeletal muscle cells, were found in the acne patients who had been treated with isotretinoin. However, when S-CAIII and S-Myo were studied in 24 patients (16 males, 8 females) before and during isotretinoin treatment, no constant increases in these markers could be observed. When individual patients were followed for several months, transient increases or decreases could be observed. The changes in S-CAIII, or S-Myo, did not correlate with the dose of isotretinoin, nor with the duration of the treatment. The results suggest that systemic isotretinoin does not specifically affect skeletal or myocardial muscles. The increases in these markers observed in the course of dermatological diseases and isotretinoin treatment are obviously due to other factors, such as exercise.

The effect of systemic glucocorticoid treatment on collagen synthesis in patients with various dermatoses was studied by measuring the carboxyterminal propeptide of type I procollagen (PICP) and the aminoterminal propeptide of type III procollagen (PIIINP) in serum. Changes in the propeptide concentrations were compared with those of osteocalcin, which reflects osteoblastic activity, and tartrate resistant acid phosphatase (TRAP), which reflects osteoclastic activity. The treatment caused significant decreases in levels of PICP, PIIINP and osteocalcin of 38, 34 and 49%, respectively (P less than 0.001). For TRAP, both increases and decreases were seen. The effects on PICP and PIIINP were evident 2-4 days after the onset of steroid therapy. The decrease in PICP was dose-related (r = 0.470, P less than 0.005) but even relatively small doses (0.1 mg of prednisone/kg/1 day) caused a significant reduction in PICP. After cessation of treatment, the levels of PICP returned to the pretreatment level in 1 week. The present study demonstrates that systemic glucocorticoid therapy in humans suppresses the synthesis of type I and III collagens and also non-collagenous bone matrix proteins.

Collagen is synthesized as procollagen and large extra domains known as propeptides are cleaved off enzymatically. In the present study we have measured the carboxyterminal propeptide of type I collagen (PICP) and the aminoterminal propeptide of type III collagen (PIIINP) in blister fluids of human skin. High concentrations of PICP were found in the spontaneous blisters of patients with bullous pemphigoid, erysipelas, or erythema multiforme. Detectable amounts were also found in suction blisters induced on healthy skin. Because the concentrations in suction blisters were several times higher than in corresponding serum, most of PICP and PIIINP was derived from the underlying dermis. This method was used for assessing type I and type III collagen synthesis after topical glucocorticoid treatment. Clobetasol-17-propionate (CP) decreased the concentrations of PICP by 75% after 1 d of treatment, the maximum inhibition (92%) being found after 2 d treatment. PIIINP was also affected. Hydrocortisone and hydrocortisone-17-butyrate also decreased the concentrations of PICP and PIIINP, but less markedly than CP. Partial recovery was seen 3 d after stopping the treatment. Thus measurement of collagen type specific propeptides in suction blisters can be used as an estimate of collagen synthesis in vivo, avoiding both local anesthesia and skin biopsing. With radioimmunoassays for PICP and PIIINP a large number of samples can also be processed simultaneously.

Glucocorticoids are effective for the treatment of various inflammatory skin diseases, but their long-term use may lead to serious side-effects such as osteoporosis and skin atrophy. The incidence of skin atrophy following application of potent corticosteroids is especially high among children and the elderly. During recent years the effects of glucocorticoids on connective tissue have been elucidated, and it is evident that skin atrophy is mostly due to a decrease in collagen synthesis. Since collagen is the most abundant protein in the skin, the inhibition of its synthesis leads to atrophy. This review discusses the molecular mechanisms of glucocorticosteroid-induced skin atrophy and therapeutic possibilities.

The effects of solar-simulated UV-irradiation on the activity of antioxidant enzymes and the amount of diene conjugation were studied in human epidermis in vivo. A single dose of UV-irradiation was found to result in a transient reduction in superoxide dismutase activity and this was followed by increased amounts of conjugated diene double bonds, an index for oxidative stress. This suggests that in-vivo exposure of human epidermis to solar-simulated UV-irradiation causes changes in the enzymic antioxidant defence system which, in turn, are accompanied by increased level of oxidative stress.