Neutrophil collagenase (matrix metalloproteinase-8 or MMP-8) is regarded as being synthesized exclusively by polymorphonuclear neutrophils (PMN). However, in vivo MMP-8 expression was observed in ...mononuclear fibroblast-like cells in the rheumatoid synovial membrane. In addition, we detected MMP-8 mRNA expression in cultured rheumatoid synovial fibroblasts and human endothelial cells. Up-regulation of MMP-8 was observed after treatment of the cells with either tumor necrosis factor-alpha (10 ng/ml) or phorbol 12-myristate 13-acetate (10 nM). Western analysis showed a similar regulation at the protein level. The size of secreted MMP-8 was 50 kDa, which is about 30 kDa smaller than MMP-8 from PMN. Conditioned media from rheumatoid synovial fibroblasts contained both type I and II collagen degrading activity. However, degradation of type II collagen, but not that of type I collagen, was completely inhibited by 50 microM doxycycline, suggesting specific MMP-8 activity. In addition, doxycycline down-regulated MMP-8 induction, at both the mRNA and protein levels. Thus MMP-8 exerts markedly wider expression in human cells than had been thought previously, implying that PMN are not the only source of cartilage degrading activity at arthritic sites. The inhibition of both MMP-8 activity and synthesis by doxycycline provides an incentive for further studies on the clinical effects of doxycycline in the treatment of rheumatoid arthritis.
Objectives: Sjögren's syndrome (SS) is a female-dominant autoimmune disease characterized by androgen depletion and defective dehydroepiandrosterone (DHEA) processing enzymatic machinery in the ...salivary glands. We hypothesized that, because of these local failures, DHEA replacement therapy would be unable to improve the local androgen deficiency in SS salivary glands.
Methods: DHEA-deficient female SS patients (n = 12) were treated with placebo for 4 months followed by DHEA 50 mg q.d. for 4 months. Serum and saliva, collected in the morning before the trial and after both periods, were analysed for pro-hormones, androgens, and androgen metabolite using an enzyme-linked immunosorbent assay (ELISA).
Results: DHEA treatment increased serum DHEA-sulfate from 1.3 ± 0.1 to 6.4 ± 1.3 µM (p = 0.005), DHEA from 16.5 ± 2.8 to 34.8 ± 8.2 nM (p = 0.012), androstenedione from 3.1 ± 0.3 to 17.2 ± 1.9 nM (p = 0.002), free testosterone from 2.2 ± 0.1 to 7.7 ± 1.1 pM (p = 0.002), DHT from 275.5 ± 24.4 to 834.6 ± 122.8 pM (p = 0.002) and 3-α-diol-G from 3.8 ± 0.6 to 13.6 ± 2.0 nM (p = 0.001). However, only salivary DHEA and DHT outputs increased significantly and 25% of the patients showed no increases, except for DHEA itself. Outputs of active androgens (T, DHT) and 3-α-diol-G metabolite correlated with salivation.
Conclusions: The local androgen deficiency in SS salivary glands is not only caused by low serum DHEA(-S) because restoration of systemic androgen levels by DHEA treatment did not correct local androgen depletion. This could be explained by low or no capacity of DHEA-substituted patients to convert the pro-steroid to active androgen metabolites. Such intracrine failures affect women in particular, who must produce their salivary T and DHT locally from DHEA.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Increased production of proteinases, such as matrix metalloproteinases (MMPs), is a characteristic feature of malignant tumors. Some human cancers and cell lines derived from them also express ...trypsinogen, but the function of the extrapancreatic trypsin has remained unclear. In this study we cloned and sequenced trypsinogen-2 cDNA from human COLO 205 colon carcinoma cells and characterized the ability of the enzyme to activate latent human type IV procollagenases (proMMP-2 and proMMP-9). As shown by cloning and N-terminal amino acid sequencing, the amino acid sequence of tumor-associated trypsin-2 is identical to that of pancreatic trypsin-2. We found that both pancreatic trypsin-2 and tumor cell-derived trypsin-2 are efficient activators of proMMP-9 and are capable of activating proMMP-9 at a molar ratio of 1:1000, the lowest reported so far. Human trypsin-2 was a more efficient activator than widely used bovine trypsin and converted the 92-kDa proMMP-9 to a single 77-kDa product that was not fragmented further. The single peptide bond cleaved by trypsin-2 in proMMP-9 was Arg87-Phe88. The generation of the 77-kDa species coincided with the increase in specific activity of MMP-9. In contrast, trypsin-2 only partially activated proMMP-2. Trypsin-2 cleaved the Arg99-Lys100 peptide bond of proMMP-2 generating 62–65-kDa MMP-2 species. Trypsin-2-induced proMMP-2 and -9 conversions were inhibited by tumor-associated trypsin inhibitor added either prior to or during activation indicating that proMMPs were not activated autocatalytically. Trypsin-2 also activated proMMPs associated with tissue inhibitor of matrix metalloproteinases, the complexes of which are thought to be the major MMP forms in vivo. The ability of human tumor cell-derived trypsin-2 to activate latent MMPs suggests a role for trypsin-2 in initiating the proteinase cascade that mediates tumor invasion and metastasis formation.
A critical step in cancer growth and metastasis is the dissolution of the extracellular matrix surrounding the malignant tumor, which leads to tumor cell invasion and dissemination. Type I collagen ...degradation involves the initial action of collagenolytic matrix metalloproteinases (MMP-1, -8, and -13) activated by MMP-3 (stromelysin-1). The role of interactive matrix serine proteinases (MSPs), including tumor-associated trypsinogens, has been unclear in collagenolysis. Now, we provide evidence that the major isoenzyme of human tumor-associated trypsinogens, trypsin-2, can directly activate three collagenolytic proMMPs as well as proMMP-3. These proMMP activations are inhibited by tumor-associated trypsin inhibitor (TATI). Furthermore, we demonstrate that trypsin-2 efficiently degrades native soluble type I collagen, which can be inhibited by TATI. However, cell culture studies showed that trypsin-2 transfection into the HSC-3 cell line did not result in MMP-1, -3, -8, and -13 activation but affected MMP-3 and -8 production at the protein level. These findings indicate that human trypsin-2 can be regarded as a potent tumor-associated matrix serine protease capable of being the initial activator of the collagenolytic MMP activation network as well as directly attacking type I collagen.
•Effects of year-to-year variation of air temperature on plant hardening were studied.•A novel method, combining biometeorology with plant ecophysiology, was introduced.•Analyses of climate data were ...combined with growth chamber experiments.•In most years air temperature does not accelerate early hardening in Scots pine seedlings.•By means of the novel method, designs for further experiments were identified.
The study addressed the effect of year-to-year variation in air temperature on the early needle frost hardening of first-year Scots pine (Pinus sylvestris L.) seedlings in autumn. To this end a novel method, combining biometeorological and plant ecophysiologal research, was introduced. In the biometeorological part, climatic year-to-year variation in air temperature during August and September was examined by analysing a 51-year set of daily air temperature data from central Finland. The cumulative occurrence of low air temperatures in August and September was quantified by calculating a cold sum for that period each year, and the climatic year-to-year variation of the cold sum accumulation was subsequently determined. Similar cold sum calculations were carried out for different air temperature treatments in hypothetical growth chamber experiments. By comparing the results of these two sets of calculations, experimental designs were defined for air temperature treatments covering the climatic year-to-year variation of cold sum accumulation in August and September. In the ecophysiological part of the study, the effects of low air temperatures on the early needle frost hardening of Scots pine seedlings were studied experimentally over two years in central Finland, using the air temperature treatments defined in the first part of the study. The hardening treatments were implemented in growth chambers under conditions simulating natural autumn conditions: gradually increasing night length combined with decreasing and diurnally fluctuating air temperature. Out of the eight air temperature treatments applied, only one had a clear effect of accelerating the hardening. Comparisons of the cold sum accumulations in the experimental treatments with those in natural conditions suggest that low air temperatures do not accelerate the early frost hardening of Scots pine seedlings in most years; further experimental studies are needed in order to determine the frequency of the years when they do. The results of the cold sum comparisons in the present study will help to identify the experimental designs needed in forthcoming studies.
Käpylä Rehabilitation Centre is in Finland the only unit taking care of the subacute rehabilitation activities of patients with spinal cord injury (SCI). The annual incidence of new patients with SCI ...is 55 (1.1 per 100,000 inhabitants). The ankylosed spine (AS) is reported to be at greater risk for fracture and SCI. The aim of the study was to clarify if this higher risk of ankylosing spondylitis (AS) could also be detected among patients with traumatic SCI rehabilitated at Käpylä Rehabilitation Centre. Further, the aim was to evaluate the characteristics of patients with traumatic SCI as a complication to AS in order to develop prevention of SCI in patients with AS.
Patient data was gathered from the patient register covering all Finnish patients with traumatic SCI (n = 1,103) rehabilitated at Käpylä Rehabilitation Centre from the year 1979 to 1998. The patient journals were subjected to a detailed and systematic analysis. Data about patients with a history of AS (n = 19; 18 men, 1 woman) was then compared to the data about all the patients with SCI (n = 1,103; 902 men, 201 women).
Based on the national prevalence data, the incidence rate of patients with AS for traumatic SCI was found to be 11.4 times greater than expected for the population at large. The mean age of the patients with AS was clearly higher (55.3 yrs) than the mean age of the whole group of patients (36.4 yrs) with traumatic SCI. The neurologic injury was at the cervical level in 84% of the patients with AS, but only in 48% of the patients with traumatic SCI in general. Among the patients with AS, the SCI was caused by slipping in 53% of the cases, whereas slipping was the reason for SCI only in 7% of the cases in general.
Patients with AS seem to run a higher risk of traumatic SCI than the people at large, and the injury levels are higher. In particular, male patients with advanced AS should be instructed to install preventive devices such as night lights and handrails, supports or head rests when driving a car, and they should avoid walking on slippery surfaces, loose carpets etc. They also should be encouraged to avoid excessive use of alcohol and activities involving the risk of physical injury such as contact sports.
Objectives
Oral lichen planus (
OLP
) is an autoimmune disease characterized by a band‐like T‐cell infiltrate below the apoptotic epithelial cells and degenerated basement membrane. We tested the ...hypothesis that the high‐affinity histamine H
4
receptors (H
4
Rs) are downregulated in
OLP
by high histamine concentrations and proinflammatory T‐cell cytokines.
Materials and Methods
Immunohistochemistry and immunofluorescence staining, image analysis and quantitative real‐time polymerase chain reaction of tissue samples and cytokine‐stimulated cultured
SCC
‐25 and primary human oral keratinocytes.
Results
H
4
R immunoreactivity was weak in
OLP
and characterized by mast cell (
MC
) hyperplasia and degranulation. In contrast to controls, H
4
R immunostaining and
MC
counts were negatively correlated in
OLP
(
P
= 0.003). H
4
R agonist at nanomolar levels led to a rapid internalization of H
4
Rs, whereas high histamine concentration and interferon‐
γ
decreased
HRH
4
‐gene transcripts.
Conclusion
Healthy oral epithelial cells are equipped with H
4
R, which displays a uniform staining pattern in a
MC
‐independent fashion. In contrast, in
OLP
, increased numbers of activated
MC
s associate with increasing loss of epithelial H
4
R. Cell culture experiments suggest a rapid H
4
R stimulation‐dependent receptor internalization and a slow cytokine‐driven decrease in H
4
R synthesis. H
4
R may be involved in the maintenance of healthy oral mucosa. In
OLP
, this maintenance might be impaired by
MC
degranulation and inflammatory cytokines.
In Finland, in recent years, the combustion of dry reed canary grass (RCG, Phalaris arundinacea) grown intensively on cutover peatlands, has decreased markedly. We therefore made experiments in two ...areas to assess the alternative of using freshly harvested RCG grown for biogas production on cutover peatland. We measured both biogas production and combustion energy release. The experiments show that the RCG biomass yields in total solids (TS) in both areas, with two cuts a year, were surprisingly small (yields of 2.7 and 4.2 Mg ha-1 1 Mg ha-1 = 100 g m-2); having biogas and combustion potentials, on the two areas, of 277–348 dm3 kg-1 VS (volatile solids) and 14.8–16.3 MJ kg-1 TS, and 11.8–21.9 MWh ha-1 in combustion. Fresh RCG may produce larger biomass yields if cut several times a year, together with lower lignin proportion, and better suitability for biogas production compared with spring harvested dry RCG. For cutover peatlands there are several after-use possibilities, however, with different benefits and challenges. For example, peat soil emissions may be affected during the after-use period, and this should be considered when planning the use of cutover peatlands.
To study the effect of oral clodronate on structural damage and bone metabolism in rheumatoid arthritis (RA).
In this 2-year proof-of-concept study, sixty patients with at least moderately active RA ...were randomised to receive anti-rheumatic therapy alone or together with oral clodronate 1600 mg daily. Radiographs of hands and feet and serum samples for bone biomarkers were studied at baseline and at 24 months.
At 24 months, progression of radiographic joint damage was similar in the 2 groups. Clodronate suppressed carboxyterminal cross-linked peptide of type I collagen (p=0.03) and aminoterminal propeptide of type I procollagen (p=0.01). Eight patients (27%) withdrew from clodronate therapy due to adverse drug reactions.
Oral clodronate did not retard the focal bone damage in RA despite its beneficial effect on overall bone metabolism, as judged by the decrease in the reference bone biomarkers.
Objective
The conventional H1 and H2 histamine receptors have >10,000‐fold lower avidity for histamine than H4 histamine receptor, which has been implicated in autoimmune diseases. This study was ...undertaken to compare H4 histamine receptor levels in the salivary glands (SGs) of healthy controls with those in the SGs of patients with primary Sjögren's syndrome (SS).
Methods
H4 histamine receptor messenger RNA (mRNA) was analyzed using real‐time quantitative polymerase chain reaction, and the receptor protein was examined using immunostaining. Effects of the H4 histamine receptor agonist ST‐1006 on cytokine synthesis by human SG (HSG) cells were analyzed using xMAP technology and enzyme‐linked immunosorbent assay.
Results
Healthy SGs contained H4 histamine receptor mRNA. The receptor protein was localized to the acinar and ductal epithelial cells. H4 histamine receptor agonist stimulated HSG cells to produce the cytokines interleukin‐8 and vascular endothelial growth factor. SS patients had low H4 histamine receptor levels.
Conclusion
H1 and H2 histamine receptor antagonists are not effective in the treatment of autoimmune diseases. However, such antagonists do not affect the newly discovered H4 histamine receptor. Dendritic cells and lymphocytes are nonprofessional histamine‐producing cells, which produce histamine at 100–1,000‐fold lower rates than mast cells do. Saliva contains only 0.31–12.4 ng/ml histamine, which is too low to stimulate H1 or H2 histamine receptor, but stimulates H4 histamine receptor half maximally. Our findings show that H4 histamine receptor is strongly expressed in tubuloacinar SG cells, which emphasizes the role of these cells in the pathogenesis of SS.
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