| 1. |
- Ihalainen, Saara, et al.
(author)
-
Proteome analysis of cultivated vascular smooth muscle cells from a CADASIL patient
- 2007
-
In: Molecular Medicine. - 1076-1551 .- 1528-3658. ; 13:5-6, s. 305-314
-
Journal article (peer-reviewed)abstract
- Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a vascular dementing disease caused by mutations in NOTCH3 gene, a majority of which are missense mutations leading to an uneven number of cysteine residues in epidermal growth factor like repeats in the extracellular domain of Notch3 receptor (N3ECD). Disease is characterized by degeneration of vascular smooth muscle cells (VSMC) and accumulation of N3ECD on the VSMCs of small and middle-sized arteries. Recent studies have demonstrated that impairment of Notch3 signaling is not the primary cause of the disease. In the present study we have characterized the protein expression pattern of a unique material of genetically genuine cultured human CADASIL VSMCs by proteomic analysis. We identified 11 differentially expressed proteins, which are involved in protein degradation and folding, contraction of VSMCs and cellular stress. Based on the results the misfolding of Notch3 seems to cause endoplasmic reticulum stress and activation of unfolded protein response leading to increased reactive oxygen species and inhibition of cell proliferation. In addition, upregulation of contractile proteins suggests an alteration in the signalling system of VSMC contraction. The accumulation of the N3ECD on the cell surface possibly upregulates the angiotensin II regulatory feedback loop and thereby enhances the readiness of the cells to respond to angiotensin II stimulation.
|
|
| 2. |
- Jortikka, Matti, et al.
(author)
-
The role of microtubules in the regulation of proteoglycan synthesis in chondrocytes under hydrostatic pressure.
- 2000
-
In: Archives of Biochemistry and Biophysics. - : Elsevier. - 0003-9861 .- 1096-0384. ; 374:2, s. 172-180
-
Journal article (peer-reviewed)abstract
- Chondrocytes of the articular cartilage sense mechanical factors associated with joint loading, such as hydrostatic pressure, and maintain the homeostasis of the extracellular matrix by regulating the metabolism of proteoglycans (PGs) and collagens. Intermittent hydrostatic pressure stimulates, while continuous high hydrostatic pressure inhibits, the biosynthesis of PGs. High continuous hydrostatic pressure also changes the structure of cytoskeleton and Golgi complex in cultured chondrocytes. Using microtubule (MT)-affecting drugs nocodazole and taxol as tools we examined whether MTs are involved in the regulation of PG synthesis in pressurized primary chondrocyte monolayer cultures. Disruption of the microtubular array by nocodazole inhibited [(35)S]sulfate incorporation by 39-48%, while MT stabilization by taxol caused maximally a 17% inhibition. Continuous hydrostatic pressure further decreased the synthesis by 34-42% in nocodazole-treated cultures. This suggests that high pressure exerts its inhibitory effect through mechanisms independent of MTs. On the other hand, nocodazole and taxol both prevented the stimulation of PG synthesis by cyclic 0. 5 Hz, 5 MPa hydrostatic pressure. The drugs did not affect the structural and functional properties of the PGs, and none of the treatments significantly affected cell viability, as indicated by the high level of PG synthesis 24-48 h after the release of drugs and/or high hydrostatic pressure. Our data on two-dimensional chondrocyte cultures indicate that inhibition of PG synthesis by continuous high hydrostatic pressure does not interfere with the MT-dependent vesicle traffic, while the stimulation of synthesis by cyclic pressure does not occur if the dynamic nature of MTs is disturbed by nocodazole. Similar phenomena may operate in cartilage matrix embedded chondrocytes.
|
|
| 3. |
- Lammi, Mikko, 1961-, et al.
(author)
-
Expression of reduced amounts of structurally altered aggrecan in articular cartilage chondrocytes exposed to high hydrostatic pressure.
- 1994
-
In: Biochemical Journal. - : Portland Press Ltd.. - 0264-6021 .- 1470-8728. ; 304, s. 723-730
-
Journal article (peer-reviewed)abstract
- The effect of hydrostatic pressure on proteoglycan (PG) metabolism of chondrocyte cultures was examined using a specially designed test chamber. Primary cultures of bovine articular chondrocytes at confluence were exposed for 20 h to 5 and 30 MPa continuous hydrostatic pressures and 5 MPa hydrostatic pulses (0.017, 0.25 and 0.5 Hz) in the presence of [35S]sulphate. Northern blot analyses showed that chondrocyte cultures used in this study expressed abundant mRNA transcripts of aggrecan, typical of chondrocytes, but not versican. The cultures also expressed biglycan and decorin. Enzymic digestions with keratanase and chondroitinases AC, ABC and B and subsequent SDS/agarose gel electrophoresis confirmed the synthesis of aggrecans and small dermatan sulphate PGs. The continuous 30 MPa pressure reduced total PG synthesis by 37% as measured by [35S]sulphate incorporation, in contrast to the 5 MPa continuous pressure which had no effect. The high static pressure also reduced total [3H]glucosamine incorporation by 63% and total [14C]leucine incorporation by 57%. The cyclic pressures showed a frequency-dependent stimulation (0.5 Hz, 11%) or inhibition (0.017 Hz, -17%) of [35S]sulphate incorporation. Aggrecans secreted under continuous 30 MPa pressure showed a retarded migration in 0.75% SDS/agarose gel electrophoresis and they also eluted earlier on Sephacryl S-1000 gel filtration, indicative of a larger molecular size. The increased size was consistent with an increase of average glycosaminoglycan chain length as determined by Sephacryl S-300 gel filtration. No change in aggrecan size was observed with the lower (5 MPa) static or cyclic pressures. Continuous 30 MPa hydrostatic pressure slightly reduced the steady-state mRNA level of aggrecan, in parallel with the decline in PG synthesis measured by [35S]sulphate incorporation. The results demonstrated that high hydrostatic pressure could influence the synthesis of PGs, especially of aggrecans, in chondrocytes both at the transcriptional and translational/post-translational levels.
|
|
| 4. |
- Loponen, Niina, et al.
(author)
-
Hypertension in NF1: A closer look at the primacy of essential hypertension versus secondary causes
- 2024
-
In: Molecular Genetics and Genomic Medicine. - 2324-9269. ; 12:1
-
Journal article (peer-reviewed)abstract
- Background: We aimed to analyze hypertension in neurofibromatosis type 1 (NF1) in a Finnish population-based cohort in 1996–2014. Methods: A cohort of 1365 individuals with confirmed NF1 was compared with a control cohort of 13,923 individuals matched for age, sex, and area of residence. Diagnoses of hypertension were retrieved from the Finnish Care Register for Health Care. These registered data were separately analyzed for secondary and essential hypertension. Purchases of antihypertensive drugs were queried from the Finnish Register of Reimbursed Drug Purchases. Results: We identified 115 NF1 patients with hospital diagnosis of hypertension. Our findings revealed a hazard ratio (HR) of 1.64 (95% CI 1.34–2.00, p < 0.001) in NF1 versus controls. NF1 patients presented with a significantly increased hazard for both secondary hypertension (n = 9, HR 3.76, 95% CI 1.77–7.95, p < 0.001) and essential hypertension (n = 98, HR 1.73, 95% CI 1.39–2.14, p < 0.001). No difference in the HR of hypertension was observed between men and women, while NF1 patients with essential hypertension were, on average, younger than the controls. The proportions of individuals with antihypertensive medication did not differ between NF1 patients and controls (OR 0.85). Conclusion: NF1 is a risk factor for hypertension. Despite the recognized risk for secondary hypertension, essential hypertension is the predominant type in NF1.
|
|
| 5. |
- Nelimarkka, Lassi, et al.
(author)
-
Expression of small extracellular chondroitin/dermatan sulfate proteoglycans is differentially regulated in human endothelial cells.
- 1997
-
In: Journal of Biological Chemistry. - : Elsevier BV. - 0021-9258 .- 1083-351X. ; 272:19, s. 12730-12737
-
Journal article (peer-reviewed)abstract
- We have examined the expression of the small extracellular chondroitin/dermatan sulfate proteoglycans (CS/DS PGs), biglycan, decorin, and PG-100, which is the proteoglycan form of colony stimulating factor-1, in the human endothelial cell line EA.hy 926. We have also examined whether modulation of the phenotype of EA.hy 926 cells by tumor necrosis factor-alpha (TNF-alpha) is associated with specific changes in the synthesis of these PGs. We demonstrate that EA.hy 926 cells, when they form monolayer cultures typical of macrovascular endothelial cells, express and synthesize detectable amounts of biglycan and PG-100, but not decorin. On SDS-polyacrylamide gel electrophoresis both PGs behave like proteins of the relative molecular weight of approximately 250,000. TNF-alpha that changed the morphology of the cells from a polygonal shape into a spindle shape and that also stimulated the detachment of the cells from culture dish, markedly decreased the net synthesis of biglycan, whereas the net synthesis of PG-100 was increased. These changes were parallel with those observed at the mRNA level of the corresponding PGs. The proportions of the different sulfated CS/DS disaccharide units of PGs were not affected by TNF-alpha. Several other growth factors/cytokines, such as interferon-gamma, fibroblast growth factors-2 (FGF-2) and -7 (FGF-7), interleukin-1beta, and transforming growth factor-beta, unlike TNF-alpha, modulated neither the morphology nor the biglycan expression of EA.hy 926 cells under the conditions used in the experiments. However, PG-100 expression was increased also in response to FGF-2 and -7 and transforming growth factor-beta. None of the above cytokines, including TNF-alpha, was able to induce decorin expression in the cells. Our results indicate that the regulatory elements controlling the expression of the small extracellular CS/DS PGs in human endothelial cells are different.
|
|
