| 1. |
- Gunnarsson, Gudjon, et al.
(författare)
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Inhibitory effect of known antioxidants and of press juice from herring (Clupea harengus) light muscle on the generation of free radicals in human monocytes
- 2006
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Ingår i: Journal of Agricultural and Food Chemistry. - : American Chemical Society (ACS). - 0021-8561 .- 1520-5118. ; 54:21, s. 8212-8221
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Tidskriftsartikel (refereegranskat)abstract
- Reactive oxygen species (ROS) can cause oxidative stress, which has been linked to various diseases. It has been suggested that antioxidant-rich foods can reduce such oxidative stress. However, the lack of suitable model systems to screen for in vivo effects of food-derived antioxidants has prevented a clear consensus in this area. In this study, the aim was to use a single-cell model system (human monocyte) to evaluate whether certain pure antioxidants and complex muscle extracts (herring light muscle press juice, PJ) could prevent ROS formation under in vivo like conditions. ROS were excreted from the monocytes upon stimulation with phorbol myristate acetate and were then detected as isoluminol-enhanced chemiluminescence (CL). Adding 2000 units of catalase and 50 units of superoxide dismutase to the monocytes model lowered the CL response by 35 and 86%, respectively. Ascorbate (14.1 mM) lowered the response by 99%, alpha-tocoperhol (188 microM) by 37%, and Trolox (50 microM) by almost 100%. Crude herring PJ gave a dose-dependent reduction in the CL response. At 10, 100, and 1000 times dilution, the PJ reduced the CL signal by 93, 60.5, and 10.6%. PJ fractionated into low molecular weight (LMW) (<1000 Da) and high molecular weight (>3500 Da) fractions decreased the CL response by 52.9 and 71.4%, respectively, at a 100-fold dilution. Evaluation of the PJ samples in the oxygen radical absorbance capacity test indicated that proteins may be the primary radical scavenging compounds of PJ, whereas the ROS-preventing effect obtained from the LMW fraction may also be attributed to other mechanisms. Thus, this study proved that the monocyte assay can be a useful tool for studying whether food-derived antioxidants can limit ROS production under physiologically relevant conditions. It also showed that herring contains numerous aqueous compounds demonstrating antioxidative effects in the monocyte model system.
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| 2. |
- Omerovic, Elmir, 1968, et al.
(författare)
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Aqueous fish extract increases survival in the mouse model of cytostatic toxicity
- 2008
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Ingår i: Journal of Experimental & Clinical Cancer Research. - : Springer Science and Business Media LLC. - 1756-9966 .- 0392-9078. ; 4:27
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Tidskriftsartikel (refereegranskat)abstract
- Background: Treatment of cancer patients with anthracycline antibiotic doxorubicin (DOX) may be complicated by development of acute and chronic congestive heart failure (CHF), malignant arrhythmias and death. The aim of this study was to test whether an aqueous low molecular weight (LMW) extract from cod muscle decreases acute mortality in the mouse model of acute CHF caused by DOX. Methods: A LMW fraction (< 500 Da) of the aqueous phase of cod light muscle (AOX) was used for treatment of male BALB/c mice (similar to 25 g, n = 70). The animals were divided into four groups, DOX + AOX (n = 20), DOX + saline (NaCl) (n = 30), NaCl + AOX (n = 10) and NaCl only (n = 10). Echocardiography was performed in the separate subgroups (DOX treated n = 6 and controls n = 6) to verify the presence and the grade of acute CHF. The cod extract was delivered by subcutaneously implanted osmotic minipumps over the period of 2 weeks. High-dose injection of DOX was administered to randomly selected animals. The animals received single intraperitoneal injection of DOX (25 mg/kg) and were followed over two weeks for mortality. Results: Mortality rate was 68% lower (p < 0.05) in the mice treated with the extract. The analyses of cod extract have shown strong antioxidative effect in vitro. Conclusion: The aqueous LMW cod muscles extract decreases mortality in the mouse model of DOX induced acute CHF. This effect may be mediated by cardioprotection through antioxidative mechanisms.
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| 3. |
- Hanson, C., et al.
(författare)
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Transplanting embryonic stem cells onto damaged human corneal endothelium
- 2017
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Ingår i: World Journal of Stem Cells. - : Baishideng Publishing Group Inc.. - 1948-0210. ; 9:8, s. 127-132
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Tidskriftsartikel (refereegranskat)abstract
- AIM To investigate whether human embryonic stem cells (hESCs) could be made to attach, grow and differentiate on a human Descemet's membrane (DM). Spontaneously differentiated hESCs were transferred onto a human corneal button with the endothelial layer removed using ocular sticks. The cells were cultured on a DM for up to 15 d. The genetically engineered hESC line expressed green fluorescent protein, which facilitated identification during the culture experiments, tissue preparation, and analysis. To detect any differentiation into human corneal endothelial-like cells, we analysed the transplanted cells by immunohistochemistry using specific antibodies. We found transplanted cells form a single layer of cells with a hexagonal shape in the periphery of the DM. The majority of the cells were negative for octamer-binding transcription factor 4 but positive for paired box 6 protein, sodium potassium adenosine triphosphatase (NaKATPase), and Zona Occludens protein 1. In four of the 18 trials, the transplanted cells were found to express CK3, which indicates that the stem cells differentiated into corneal epithelial cells in these cases. It is possible to get cells originating from hESCs to become established on a human DM, where they grow and differentiate into corneal endothelial-like cells in vitro.
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| 4. |
- Jonsson, Olof, 1941, et al.
(författare)
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Enhanced post-ischaemic recovery in rabbit kidney after pretreatment with an indeno-indole compound and ascorbate monitored in vivo by 31P magnetic resonance spectroscopy.
- 2003
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Ingår i: Scandinavian Journal of Urology and Nephrology. - 0036-5599. ; 37:6, s. 450-455
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To investigate whether combined pretreatment with lipid- and water-soluble antioxidants gave better restoration of energy phosphates after ischaemia–reperfusion of rabbit kidneys than single pretreatment with a lipid-soluble antioxidant. Material and Methods: Thirteen New Zealand white rabbits were used for the study. Changes in energy phosphates were measured in vivo using volume-selective 31P magnetic resonance spectroscopy. The indeno–indole compound H290/51 was chosen as a lipid-soluble antioxidant and ascorbate as a water-soluble antioxidant. Results: The combined pretreatment led to significantly better restoration of the β-adenosine triphosphate:inorganic phosphate ratio after 60 min of ischaemia and 120 min of reperfusion compared with the single pretreatment. Analyses of blood pressure and blood gas changes showed that the beneficial effect of combined pretreatment was not caused by a better general condition of the animals in that group but by a direct effect on the kidneys. Conclusions: Combined pretreatment with lipid- and water-soluble antioxidants leads to better restoration of energy phosphates in rabbit kidneys subjected to ischaemia–reperfusion compared with single pretreatment with a lipid-soluble antioxidant.
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| 5. |
- Lindgård, Ann, 1977
(författare)
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Improved bioenergetic recovery during experimental ischemia and reperfusion by irradiation
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Prolonged ischemia and reperfusion frequently occur during clinical operations. The bioenergetic status decreases during ischemia and reactive oxygen species (ROS) are formed during reperfusion, which may lead to irreversible tissue injury. During prolonged ischemia, such as in complex microsurgical operations, tissue injury should be minimized to improve the chance of full recovery and function. Irradiation has previously been shown to improve functional recovery of cold-stored rat hearts via conservation of ATP. In this thesis, we used photons at 634 nm produced from a singlet oxygen system to investigate whether irradiation improves the bioenergetic status in skeletal muscle and graft hearts and decreases ROS in monocytes, and thus decreases tissue injury. The effect of irradiation on bioenergetic status was examined in rat rectus femoris muscle in vitro following 5 h ischemia. Phosphocreatine (PCr), ATP and inorganic phosphate (Pi) levels were measured using high resolution 11.75T 31P magnetic resonance spectroscopy (MRS). PCr and ATP were significantly higher in the irradiated groups than in the non-irradiated group, but no difference in Pi was observed. The effect of irradiation on bioenergetic status was examined in rat rectus femoris muscle in vivo following 4 h ischemia and 1 reperfusion. ATP, PCr and Pi levels were measured using 2.35T 31P MRS. After 4 h ischemia, ATP levels in the irradiated group were significantly higher than in the non- irradiated group, but no difference in PCr/(PCr+Pi) levels were observed. After 1 h reperfusion, ATP and PCr/(PCr+Pi) levels in the irradiated groups were significantly higher than in the non-irradiated groups. Blood-perfusion was measured using laser Doppler flowmetry and did not differ between the groups. The effect of irradiation on xenografts was examined in vivo following heart xenotransplantation from hamster to rat. PCr and ATP levels were measured daily using 2.35T 31P MRS over 4 days. Irradiation of xenografts before reperfusion preserved the energetic status of hamster grafts, as demonstrated by a significantly higher PCr/ATP ratio in the irradiated group than in the non-irradiated group on the first postoperative day. However, irradiation did not delay the rejection process in this experimental model. Finally, the effect of irradiation was examined in human monocytes. Intracellular ROS, nitric oxide (NO) release and ATP were measured using chemiluminescence assays. iNOS and eNOS mRNA levels were measured using reverse transciption PCR. NO levels were significantly higher in the irradiated group than in the non-irradiated group, but no differences in iNOS or eNOS mRNA were observed. Intracellular ROS release was significantly lower in the irradiated group than in the non-irradiated group, and there was no difference in ATP levels. The salvaging effect of irradiation may have a wide range of clinical applications, for example in complex microsurgery and transplantation surgery.
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| 6. |
- Lindgård, Ann, 1977, et al.
(författare)
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Irradiation at 634 nm releases nitric oxide from human monocytes
- 2007
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Ingår i: Lasers Med Sci. - : Springer Science and Business Media LLC. - 0268-8921. ; 22:1, s. 30-6
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Tidskriftsartikel (refereegranskat)abstract
- Previous studies have shown that irradiation at 634 nm decreases the release of extracellular reactive oxygen species (ROS) without affecting viability in human monocytes. Here, we examined the effect of irradiation at 634 nm on the release of nitric oxide (NO), activation of inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS), and release of intracellular ROS. Chemiluminescence assays were used to measure NO release, intracellular ROS, and adenosine triphosphate levels (to assess cell viability). Levels of iNOS and eNOS mRNA were analyzed using PCR. Irradiation resulted in elevated levels of NO but had no effect on iNOS or eNOS. Irradiation also caused a decrease in levels of intracellular ROS and had no effect on cell viability. Our studies indicate that irradiation at 634 nm releases NO, possibly from a preformed store, and reduces the production of intracellular ROS without affecting cell viability. Irradiation at 634 nm may have a wide range of clinical applications, including a reduction in oxidative stress-mediated injury in the vasculature.
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| 7. |
- Lindgård, Ann, 1977, et al.
(författare)
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Preservation of rat skeletal muscle energy metabolism by illumination.
- 2003
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Ingår i: Life sciences. - 0024-3205. ; 72:23, s. 2649-58
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Tidskriftsartikel (refereegranskat)abstract
- Skeletal muscle viability is crucially dependent on the tissue levels of its high energy phosphates. In this study we investigated the effect of the preservation medium Perfadex and illumination with Singlet Oxygen Energy (SOE). Singlet oxygen can be produced photochemically by energy transfer from an excited photosensitizer. The energy emitted from singlet oxygen upon relaxation to its triplet state is captured as photons at 634 nm and is here referred to as SOE. Rat hind limb rectus femoris muscles were preserved for five hours at 22 degrees C in Perfadex, saline, SOE illuminated Perfadex or SOE illuminated saline. Extracts of the muscles were analysed by 31P NMR. Data were analysed using two-way analysis of variance and are given as mean values micromol/g dry weight) +/- SEM. The ATP concentration was higher (p = 0.006) in saline groups (4.52) compared with Perfadex groups (2.82). There was no statistically significant difference in PCr between the saline groups (1.25) and Perfadex groups (0.82). However, there were higher (p = 0.003) ATP in the SOE illuminated groups (4.61) compared with the non-illuminated groups (2.73). The PCr was also higher (p < 0.0001) in the SOE illuminated groups (1.89) compared with the non-illuminated groups (0.18). In conclusion, Perfadex in this experimental model was incapable of preserving the high energy phosphates in skeletal muscle during 5 hours of ischemia. Illumination with SOE at 634 nm improved the preservation potential, in terms of a positive effect on the energy status of the muscle cell.
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| 8. |
- Lundberg, Jonas, 1961, et al.
(författare)
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Improved energetic recovery of skeletal muscle in response to ischemia and reperfusion injury followed by in vivo 31P-magnetic resonance spectroscopy.
- 2002
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Ingår i: Microsurgery. - 0738-1085 .- 1098-2752. ; 22:4, s. 158-164
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Tidskriftsartikel (refereegranskat)abstract
- It is of great clinical interest to improve postischemic tissue recovery during microsurgical transfers. The effect of singlet oxygen energy (SOE) as photon illumination at 634 nm on rat skeletal muscle during ischemia and postischemic reperfusion was investigated noninvasively and continuously by in vivo 31P-magnetic resonance spectroscopy (31P-MRS). A model of pedicled rat rectus femoris muscle was used, where phosphorous metabolites were followed before onset of ischemia (control), after 4 h of ischemia, and after 1 h of reperfusion. Two groups were studied: one control group (n = 10), and one SOE-treated group (n = 10). Blood perfusion was measured by laser Doppler flowmetry (LDF) during the study. After 4 h of ischemia, ATP levels were 72% and 51% of normal control values in the illuminated group and the control group, respectively (P < 0.05). After 1 h of postischemic reperfusion, phosphocreatine (PCr) recovered to 79% and adenosine triphosphate (ATP) to 71% in the illuminated group, whereas in the control group, the recovery was 57% and 51%, respectively (P < 0.05). It is concluded that singlet oxygen energy has a beneficial effect on the energy state of skeletal muscle during ischemia and postischemic reperfusion. © 2002 Wiley-Liss, Inc. MICROSURGERY 22:158–164 2002
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