L929 cell conditioned medium protects RAW264.7 cells from oxidative injury through inducing antioxidant enzymes

M-CSF- and L929-derived macrophages present distinct metabolic profiles with similar inflammatory outcomes

Macrophages are essential components of the immune system. Macrophages can be derived from the bone marrow of mice with either recombinant M-CSF or L929 supernatant. Recent literature considers recombinant M-CSF- and L929-derived macrophages as equals, even though L929-derived macrophages are exposed to other substances secreted in the L929 supernatant, and not only M-CSF. Thus, we decided to perform a comparative analysis of both inflammatory and metabolic profiles of macrophages differentiated under the aforementioned conditions, which is relevant for standardization and interpretation of in vitro studies. We observed that, when treated with LPS, L929macs secrete lower levels of proinflammatory cytokines (TNF-α, IL-6, IL12) and present higher glycolysis and oxygen consumption when compared with M-CSFmacs. L929macs also have increased mitochondrial mass, with higher percentage of dysfunctional mitochondria. This sort of information can help direct further studies towards a more specific approach for macrophage generation.

Interleukin-10 may participate in regulating trophoblast invasion in human placentae throughout gestation

PROBLEM

A successful human pregnancy requires cytotrophoblasts from the fetal portion of the placenta to adopt tumor-like properties. But unlike tumor metastasis, cytotrophoblast invasion is highly regulated both spatially and temporally. The mechanisms that regulate human trophoblast invasion are understood poorly.

METHOD OF STUDY

With a view to obtain some findings on the mechanisms that regulate human trophoblast invasion, we applied the semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) method to compare the expression of invasion-associated genes in cytotrophoblasts isolated from first- and third-trimester placental tissues.

RESULTS

In trophoblast cells of first-trimester pregnancy, the mRNA contents of matrix metalloproteinase (MMP)-9 and urokinase-type plasminogen activator (uPA) were higher than that in the third-trimester cytotrophoblasts, while no difference of MMP-2 mRNA expression level was found between trophoblastic cells of different gestational ages. The expression level of plasminogen activator inhibitors-1 mRNA in first-trimester cytotrophoblasts was shown to be much lower than that in trophoblast cells prepared from third-trimester placental tissues. Furthermore, expression of both tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 in cytotrophoblasts were significantly up-regulated in third-trimester when compared with the first-trimester of pregnancy. To further investigate the factors that caused the change of invasion-associated genes expression in trophoblast cells, we found that interleukin-10 (IL-10) could decrease the content of MMP-9 mRNA in cytotrophoblasts of first-trimester gestation, and the magnitude of suppression increased with increasing IL-10 concentration.

CONCLUSION

The gradually reduced trophoblast invasion with gestational weeks might be on account of the change of proteolytic enzymes/activator/inhibitor genes expression. IL-10 could be one of the factors participating in the regulation of trophoblast invasion during gestational process.

Evidence supporting antioxidant action of adipose-derived stem cells: protection of human dermal fibroblasts from oxidative stress

BACKGROUND

Mesenchymal stem cells within the stromal-vascular fraction of subcutaneous adipose tissue, adipose-derived stem cells (ADSCs), produced soluble factors and they exhibit diverse pharmacological effects in skin biology.

OBJECTIVE

The present study examines the protective effect of ADSCs for human dermal fibroblasts (HDFs) through anti-oxidation in a tert-butyl hydroperoxide (tbOOH) induced oxidative injury model.

METHODS AND RESULTS

The conditioned medium of ADSCs (ADSC-CM) was harvested and tested for antioxidant action. ADSC-CM had an antioxidant effect as potent as 100 microM ascorbic acid and various antioxidant proteins were detected in ADSC-CM by proteomic analysis. Morphological change and cell survival assay revealed that incubation with ADSC-CM aided HDFs to resist free radicals induced by tbOOH. In addition, activities of superoxide dismutase and glutathione peroxidase were enhanced in the ADSC-CM treated HDFs which confirmed the study hypothesis that ADSCs protect HDFs through antioxidant action. In a cell cycle analysis, ADSC-CM treatment reversed the apoptotic cell death induced by tbOOH and caused a decrease of sub-G1 cells with respect to untreated cells. The anti-apoptotic effect of ADSC-CM was also reproduced by caspase-3 activity assay.

CONCLUSION

These results suggest that ADSCs have potent antioxidant activity and protect HDFs from oxidative injury by decreasing apoptotic cells. Therefore, ADSCs and ADSC-CM are good candidates for control and prevention of skin damage from free radicals in various skin conditions.

DNA microarrays detect the expression of apoptosis-related genes in preeclamptic placentas

AIMS

To investigate the expression of apoptosis-related genes in preeclamptic placentas and the possible mechanism of the regulation process.

METHODS

Complementary DNA microarrays were employed to compare gene expression profiles of five preeclamptic and five normal placentas.

RESULTS

Among the 368 genes detected over 35% showed an over 2-fold difference of expression between preeclamptic placentas and normal placentas. Many genes involved in cell cycle or apoptosis were more highly expressed in preeclamptic placentas than in normal placentas. The expression of many immune-activation genes in preeclamptic placentas was also higher than that in normal placentas. Additionally, many cytokine receptor/kinase genes were also induced in preeclamptic placentas.

CONCLUSIONS

The change in expression of cell apoptosis-related genes in placentas might be involved in the pathogenesis of preeclampsia, while the activation of the immune system might be one cause of this change.

Effect of polysaccharide Krestin on the up-regulation of macrophage colony-stimulating factor gene expression in protecting mouse peritoneal macrophages from oxidative injury

Oxidative injury caused by oxidatively modified low density lipoprotein (Ox-LDL) plays an important role in the transformation of macrophages into foam cells and atherogenesis. Treatments to protect macrophages from oxidative injury will be effective in treating atherosclerosis. A macrophage-specific growth factor, macrophage colony-stimulating factor (M-CSF), was reported to be able to prevent the progression of atherosclerosis in Watanabe heritable hypercholesterolemic (WHHL) rabbits. A protein-bound polysaccharide, polysaccharide Krestin (PSK), was also proven to have effects in preventing atherosclerosis in our previous work. We proposed that, both M-CSF and PSK could protect macrophages from oxidative injury, and the effects of PSK were associated with its capability of inducing M-CSF expression. In our present results, M-CSF could alleviate the Ox-LDL- or tert-butyl hydroperoxide (tbOOH)-induced injury to mouse peritoneal macrophages, and PSK exhibited some similar effects. PSK treatment could induce M-CSF gene expression and secretion in mouse peritoneal macrophages. Furthermore actinomycin D and cycloheximide could attenuate that induction. We concluded that, maybe PSK exerted its effects on macrophages partly through the transcriptional induction of M-CSF in the cells.