Search results for "Protoporphyrins"
showing 10 items of 15 documents
Photodynamic therapy of nodular basal cell carcinoma with multifiber contact light delivery.
2006
To overcome the limited treatment depth of superficial photodynamic therapy we investigate interstitial light delivery. In the present work the treatment light was delivered using a system in which three or six clear-cut fibers were placed in direct contact with the tumor area. This placement was thought to represent a step toward general purpose interstitial PDT. Twelve nodular basal cell carcinomas were treated employing delta-aminolevulinic acid and 635 nm laser irradiation. Fluorescence measurements were performed monitoring the buildup and subsequent bleaching of the produced sensitizer protoporphyrin IX. The treatment efficacy, judged at a 28-month follow-up, showed a 100% complete re…
Haem oxygenase-1 regulates catabolic and anabolic processes in osteoarthritic chondrocytes
2007
Pro-inflammatory cytokines, matrix metalloproteinases (MMPs) and other catabolic factors participate in the pathogenesis of cartilage damage in osteoarthritis (OA). Pro-inflammatory cytokines such as interleukin-1β (IL-1β) mediate cartilage degradation and might be involved in the progression of OA. Previously, we found that haem oxygenase-1 (HO-1) is down-regulated by pro-inflammatory cytokines and up-regulated by IL-10 in OA chondrocytes. The aim of this study was to determine whether HO-1 can modify the catabolic effects of IL-1β in OA cartilage and chondrocytes. Up-regulation of HO-1 by cobalt protoporphyrin IX significantly reduced glycosaminoglycan degradation elicited by IL-1β in OA …
Regulation of the inflammatory response by tin protoporphyrin IX in the rat anterior cruciate ligament transection model of osteoarthritis
2010
The purpose of this study was to investigate several inflammatory mediators and cartilage degradation molecules as possible biomarkers of joint lesion in the anterior cruciate ligament transection (ACLT) model of osteoarthritis in rats. We also assessed whether the treatment with the anti-inflammatory agent tin protoporphyrin IX (SnPP) reduces the progression of disease. Our results indicate that serum levels of interleukin (IL)-6 and PGE2 are significantly increased in ACLT rats 10 weeks after surgery, whereas the increases in IL-1β and tumor necrosis-α were not significant. In addition, our data suggest that IL-17 is the main pro-inflammatory cytokine in the ACLT joint. We have shown that…
Heme oxygenase-1 inhibits apoptosis in Caco-2 cells via activation of Akt pathway
2005
Heme oxygenase-1 can play a protective role against cellular stress. In colon cancer cells, these effects would be relevant to oncogenesis and resistance to chemotherapy. The aim of the study was to examine the effects of heme oxygenase-1 induction on cell survival in a human colon cancer cell line, Caco-2. Serum deprivation induced apoptosis, reduced Akt and p38 phosphorylation, and increased p21(Cip/WAF1) levels. Heme oxygenase-1 induction by treatment with cobalt protoporphyrin IX resulted in resistance to apoptosis, activation of Akt, reduction in p21(Cip/WAF1) levels and modification of bcl2/bax ratio towards survival. Indomethacin reduced apoptosis but in contrast to heme oxygenase-1,…
Thermal broadening of the Soret band in heme complexes and in heme-proteins: role of iron dynamics
1994
We report the thermal broadening of the Soret band in heme-CO, heme-OH and protoporphyrin IX in the temperature range 300-20 K. For protoporphyrin IX the temperature dependent Gaussian line broadening follows the behavior predicted by the harmonic approximation in the entire temperature range investigated. In contrast, for heme-CO and heme-OH the harmonic behavior is obeyed only up to about 180 K and an anomalous line broadening increase is observed at higher temperatures. This effect is attributed to the onset of anharmonic motions of the iron atom with respect to the porphyrin plane. Comparison with previously reported analogous data for heme proteins enables us to suggest that the onset …
Potential Antioxidant Activity of Calcium and Selected Oxidative Stress Markers in Lead- and Cadmium-Exposed Workers
2020
Occupational lead (Pb) and cadmium (Cd) exposure occurs during processing and casting of nonferrous metals such as zinc. In contrast to Pb and Cd, Ca is essential for living organisms due to its important role in a multitude of functions, from cell signaling to bone growth. Pb and Cd exposure affects calcium metabolism in various ways. The aim of this study was to investigate the blood levels of Pb, Cd, and Ca and the levels of selected oxidative stress biomarkers in workers exposed to Pb and Cd. Population groups included 264 male employees in a lead-zinc smelter. The study population was divided into two subgroups based on the median of Ca serum level (2.42 mmol/l): the low-Ca-level group…
Analysis of early biochemical markers and regulation by tin protoporphyrin IX in a model of spontaneous osteoarthritis
2011
Abstract Age-related changes in joint tissues lead to osteoarthritis (OA). Detection of early changes in OA patients may help to initiate treatments before the establishment of irreversible joint destruction. STR/ort mice develop with age a severe degenerative joint disease that resembles human OA thus allowing the investigation of biochemical markers as well as new treatments in an accelerated time frame. We have analyzed the changes in serum levels of different mediators during the early phases of idiopathic OA in STR/ort mice. Serum levels of matrix metalloproteinase-3 (MMP-3) but not those of tumor necrosis factor-α, interleukin(IL)-1β, IL-17 or prostaglandin E 2 correlated with histopa…
Hemin, an inducer of heme oxygenase-1, lowers intraocular pressure in rabbits.
2007
Carbon monoxide (CO) generated from heme may induce vasodilation and exert cyto-protective properties in the eye. This study was undertaken to investigate the effects of hemin, a potent inducer of heme oxygenase-1 (HO-1), on models of ocular hypertension in rabbits.Ocular hypertension was induced by injecting alpha-chymotrypsin in both eyes under local anesthesia. Only rabbits with an intraocular pressure (IOP) of 25 mmHg or more were used. The dose-response study of the hemin effect on IOP was made by an intravenous injection of the drug (50, 75, and 100 mg/kg) and subsequent IOP monitoring every 6 h. A separate set of animals was pretreated with the HO-1 inhibitor, zinc protoporphyrin-IX …
Potential role of heme oxygenase-1 in the progression of rat adjuvant arthritis
2004
Rat adjuvant arthritis is an experimental model widely used to evaluate etiopathogenetic mechanisms in chronic inflammation. We have examined the participation of heme oxygenase-1 (HO-1) in this experimental arthritis. In this study, an increased nitric oxide (NO) production in the paw preceded the upregulation of HO-1, whereas selective inhibition of inducible NO synthase (iNOS) after the onset of arthritis decreased HO-1 expression, suggesting that the induction of this enzyme may depend on NO produced by iNOS. Therapeutic administration of the HO-1 inhibitor tin protoporphyrin IX was able to control the symptoms of arthritis. This agent significantly decreased leukocyte infiltration, hyp…
In vitro and in vivo porphyrin accumulation by C6 glioma cells after exposure to 5-aminolevulinic acid
1998
Several malignant tissues synthesize endogenous porphyrins after exposure to 5-aminolevulinic acid (5-ALA). The present experiments have been designed to elucidate whether the C6 glioma cell, a model cell for human malignant glioma, similarly synthesizes porphyrins when exposed to 5-ALA, and whether specific synthesis occurs when C6 cells are inoculated into rat brains to form a tumor. In this situation the blood-brain barrier may interfere with 5-ALA availability, and spreading of porphyrins with edema outside the tumor may occur. Flow cytometry is used to determine the course of cell volume and porphyrin fluorescence intensities in cultured C6 cells which are incubated in 1 mM 5-ALA. For …