All-trans retinoic acid (ATRA) is a vitamin A derivative and plays an important role in the regulation of cell aggregation, differentiation, apoptosis, proliferation, and inflammatory response. In recent years, some progress has been made in the role of ATRA in renal diseases, especially its protective effect on podocytes. This article reviews the research advances in podocyte injury, characteristics of ATRA, podocyte differentiation and regeneration induced by ATRA, and the protective effect of ATRA against proliferation, deposition of fibers, and apoptosis.
Apoptosis ; drug effects ; Cell Differentiation ; drug effects ; Cell Proliferation ; drug effects ; Cytoprotection ; Humans ; Podocytes ; drug effects ; physiology ; Tretinoin ; pharmacology

Inducible cyclooxygenase-2 (COX-2) has received much attention because of its role in neuro-inflammation and synaptic plasticity. Even though COX-2 levels are high in healthy animals, the function of this factor in adult neurogenesis has not been clearly demonstrated. Therefore, we performed the present study to compare the effects of pharmacological and genetic inhibition of COX-2 on adult hippocampal neurogenesis. Physiological saline or the same volume containing celecoxib was administered perorally every day for 5 weeks using a feeding needle. Compared to the control, pharmacological and genetic inhibition of COX-2 reduced the appearance of nestin-immunoreactive neural stem cells, Ki67-positive nuclei, and doublecortin-immunoreactive neuroblasts in the dentate gyrus. In addition, a decrease in phosphorylated cAMP response element binding protein (pCREB) at Ser133 was observed. Compared to pharmacological inhibition, genetic inhibition of COX-2 resulted in significant reduction of neural stem cells, cell proliferation, and neuroblast differentiation as well as pCREB levels. These results suggest that COX-2 is part of the molecular machinery that regulates neural stem cells, cell proliferation, and neuroblast differentiation during adult hippocampal neurogenesis via pCREB. Additionally, genetic inhibition of COX-2 strongly reduced neural stem cell populations, cell proliferation, and neuroblast differentiation in the dentate gyrus compared to pharmacological inhibition.
Animals ; Celecoxib/*pharmacology ; Cell Differentiation/drug effects/physiology ; Cell Proliferation/drug effects/physiology ; Cyclooxygenase 2/*genetics/metabolism ; Cyclooxygenase 2 Inhibitors/*pharmacology ; Dentate Gyrus/drug effects/*physiology ; Male ; Mice ; Mice, Knockout ; Neural Stem Cells/drug effects/physiology ; Neurogenesis/drug effects

CCL23 is a human CC chemokine with potential suppression effects on both human and murine myeloid progenitor cells both in vitro and in vivo, and only expressed and released by dendritic cells differentiated from monocytes in blood cells. However, recent study has shown that CCL23 was over-expressed in bone marrow and peripheral blood cells from pediatric patients with acute myeloid leukemia (AML). In order to investigate the effects of CCL23 on the development, therapy and prognosis of leukemia, the U937 cells, a leukemic cell strain, were adopted and cultured with rhCCL23 for 72 hours. The cell proliferation and apoptosis rate were detected by Cell Counting Kit-8 and FITC-AnnexinV/PI respectively; the morphologic changes and the expression of CCR1 (the only receptor of CCL23 known by now) were observed during the differentiation process. The results showed that no obvious effect on the proliferation, apoptosis and differentiation of U937 was found by using CCL23 alone (P > 0.05), but cultured in combination with CCL23 and PMA, the differentiation of U937 cells were promoted remarkably, during which the CCR1 expression increased (P < 0.05). It is concluded that CCL23 alone did not inhibit the proliferation and differentiation of U937, while its use in combination with PMA may possess synergistic effect on inducting differentiation of U937 through the increase of receptor CCR1 expression.
Apoptosis ; physiology ; Cell Proliferation ; drug effects ; Cell Transformation, Neoplastic ; drug effects ; Chemokines, CC ; pharmacology ; Humans ; U937 Cells

OBJECTIVETo study the proliferation effect of neural stem cells (NSCs) of ginsenoside Rg1 in vitro.

METHODNSCs from the embryonic rat (E14) were isolated, 10 mg x L(-1) BrdU were added in the medium. The NSCs were incubated together with 1, 10 micromol x L(-1) ginsenoside Rg1 for 48 hours, control group were setup. Then BrdU positive cell number were detected and counted by fluorescence microscop. The Hes1 and Mash1 mRNA expression were detected by real-time RT-PCR.

RESULTThe number of BrdU positive cells in 10 micromol x L(-1) ginsenoside Rg1 group was increased significantly compared with the control group (40.5 +/- 10.9 vs 26.2 +/- 6.0, P < 0.01), and the Hes1 mRNA expression were increased significantly (1.00 +/- 0.11) vs (1.28 +/- 0.14), P < 0.05.

CONCLUSIONginsenoside Rg1 can promote the proliferation of neural stem cells in vitro, and this effect may be induced by the up-regulation Hes1 expression.

Animals ; Cell Proliferation ; drug effects ; Ginsenosides ; pharmacology ; Multipotent Stem Cells ; drug effects ; physiology ; Neurons ; drug effects ; physiology ; Rats ; Rats, Wistar ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo study influence of serum containing Liuwei Dihuang decoction (see text) on proliferation and differentiation of osteoblast form neonatal SD rats cultured in vitro at different times and different stretch stress.

METHODSAfter osteoblast cultured for 24 hours in the serum containing Liuwei Dihuang decoction (see text) and serum in control group, the 0.5 Hz frequency, 6% and 12% stretch-stress were added. The MTT1 and the activity of ALP were measured at the 12th and 24th hours, and the data were analyzed.

RESULTS1. In the environment of stretch stress to the frequency of 0.5 Hz, and stretched for 24 hours, the osteoblast was stimulated under elongation rate of 6% and 12%; the proliferation and differentiation of osteoblast was more active under elongation rate of 12% than that of 6%. 2. There were no stimulating effects on osteoblast proliferation and differentiation of serum containing Liuwei Dihuiang decoction (see text) acted on osteoblast cells of SD rats cultured in vitro for a shot time.

CONCLUSIONStretch stress environment can enhance osteoblast proliferation and differentiation cultured in vitro.

Alkaline Phosphatase ; metabolism ; Animals ; Cell Differentiation ; drug effects ; Cell Proliferation ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Male ; Osteoblasts ; drug effects ; physiology ; Rats ; Rats, Sprague-Dawley ; Serum ; Stress, Mechanical

OBJECTIVETo investigate the effect of down-expression of inhibitor of differentiation-1 (Id-1) on the differentiation of dendritic cell sarcoma (DCS) cells in vitro.

METHODSDown-regulation of the expression of Id-1 in DCS cells was performed by RNAi, and confirmed by protein and mRNA quantitative analyses. Cellular differentiation and biological behavior including malignant phenotypes of the cells were evaluated. All experiments included negative (no treatment group and no-target siRNA) and positive (induction-differentiation drug sodium butyrate) controls.

RESULTSWhen the expression of Id-1 was down regulated, the DCS cells showed more mature morphology including cell enlargement, longer cellular extensions, more branches, and decreased nuclear/plasma ratio. Differentiation marker expression (Id-2 and CD86) was also increased. RNAi treated cells at 24 and 48 hours, showed increase percentage of cells at G0/G1 phase and less cells at S phase (P < 0.01). Importantly, the abilities of cell proliferation, colony formation and invasiveness were significantly decreased (P < 0.01), as evidenced by MTT, colony formation and transwell assays respectively.

CONCLUSIONRNAi inhibition of Id-1 protein can induce differentiation of malignant solid tumor cells along with reversion of their malignant phenotype.

Animals ; Cell Differentiation ; drug effects ; physiology ; Cell Proliferation ; drug effects ; Dendritic Cells ; cytology ; drug effects ; Down-Regulation ; Inhibitor of Differentiation Proteins ; pharmacology ; Mice ; Tumor Cells, Cultured

OBJECTIVETo examine the effects of various concentration of nicotine on bone marrow stromal cells (BMSCs) proliferation and differentiation of cartilaginous in vitro.

METHODSBMSCs was obtained from femoral bone and tibia of New-Zealand albino rabbit. The cells of the 3rd generation were used in study. Different concentration of nicotine (0, 1 x 10(-7), 1 x 10(-6), 1 x 10(-5) M) were added into BMSCs. BMSCs proliferation was analyzed by MTT assay at the 1, 4, 7, 14 days. The expression of collagen type II and aggrecan as the marker genes of cartilaginous differentiation from BMSCs were detected by reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTSMicroscope showed that BMSCs transformed from round to fusiform shape. The concentration of nicotine in 1 x 10(-7), 1 x 10(-6) M had a significant positive effect on cell proliferation and the expression of type II collagen in a time-dependent manner when supplemented in commonly used induction media (P<0.05). Concentrations of nicotine in 1 x 10(-7) can promote the expression of aggrecan at the 7th day after induction,and in 1 x 10(-5) M may inhibit the expression of type II collagen and aggrecan.

CONCLUSIONIt was implied that local application of nicotine at an appropriate concentration may be a promising approach for enhancing cartilaginous differentiation capacity of BMSCs in cartilage tissue engineering.

Aggrecans ; genetics ; Animals ; Bone Marrow Cells ; drug effects ; physiology ; Cell Differentiation ; drug effects ; Cell Proliferation ; drug effects ; Chondrocytes ; cytology ; drug effects ; Collagen Type II ; genetics ; Male ; Nicotine ; pharmacology ; RNA, Messenger ; analysis ; Rabbits ; Stromal Cells ; drug effects ; physiology

BACKGROUNDThe hematopoietic microenvironment (HM) plays a critical role in malignant cell growth, patient survival, and response to chemotherapy in hematologic malignancies. However, mechanisms associated with this environmental influence remain unclear. In this study, we investigated the role of bone marrow derived mesenchymal stem cells (MSCs) in U937 cell line, to find out the relations between leukemia drug resistance and the MSCs.

METHODSU937 cells were cultured in suspension or grew adherently with MSCs. The cell growth curve was drawn and the cell cycle was measured by flow cytometry. Apoptosis and sensitivity of U937 to daunoblastina (DNR) were quantified by DNA ladder detection and trypan blue exclusion assays, respectively. The gene expression profile chip technology was used to determine and analyze the changes in apoptosis-related gene expression after adherent culture and the expression of MDR1 mRNA was assessed by reverse transcriptional polymerase chain reaction (RT-PCR) at the same time.

RESULTSIn the adherent culture, the proliferation of the U937 cells was inhibited, the G0/G1 phase cells increased (F = 64.9726, P < 0.0001), G2/M phase cells were decreased (F = 98.1361, P < 0.0001) and the natural apoptosis rate was decreased (F = 24.0866, P < 0.0001) compared with those in the suspended culture. U937 cell viability was enhanced and cell apoptosis was blocked during DNR treatment in adherent culture with MSCs. Thirty-nine differently expressed genes were screened from the 487 apoptosis related genes in the adherent culture U937 cells. Among the 37 upregulated genes, Bcl-XL was upregulated most significantly. Two genes were downregulated. Adherent culture did not induce MDR1 mRNA expression in U937 cells.

CONCLUSIONSMSCs play a role in modulating the proliferation of U937 cells and response of U937 cells to DNR, and Bcl-XL apoptosis-inhibiting gene may be most important in determining the sensitivity of leukemic cells to treatment, which is not related to MDR1.

Apoptosis ; drug effects ; Bone Marrow Cells ; physiology ; Cell Proliferation ; Daunorubicin ; pharmacology ; Drug Resistance, Neoplasm ; Genes, MDR ; Humans ; Immunophenotyping ; Mesenchymal Stromal Cells ; physiology ; U937 Cells ; drug effects

OBJECTIVETo investigate the effects of different concentrations of Gubishu containing serum on the proliferation of rabbit articular chondrocytes cultured in vitro.

METHODSArticular chondrocytes were obtained from the cartilage of 1-month rabbit and cultured in vitro. They were randomly divided into 8 groups,blank and Gubishu groups in different concentrations (5%, 10%,15%, 20%), MTT assay method was adopted to observe the influence of Gubishu containing serum with different concentrations to the proliferation of chondrocytes after incubated 1, 3, 5, 7 and 9 days.

RESULTSThe proliferation of chondrocytes was dependent on the concentration in Gubishu groups. At same time point,there was significant value between every groups, 20% concentration was greatest (P<0.05); There was significant differences between 5%, 10% and 20% concentration of the blank groups at same time point (P<0.05), and was not between 15% and 20% concentration at the 1, 3, 5 and 7 days (P>0.05), 20% concentration of the blank group was greatest. 20% concentrations of Gubishu containing serum was significantly greater than 20% concentrations of blank group at the 1, 3, 5 and 7 days (P<0.05).

CONCLUSION20% concentrations of Gubishu containing serum can significantly increase the proliferation of chondrocytes, and bring the logarithmic growth period forward to the 3 day.

Animals ; Cartilage, Articular ; cytology ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Chondrocytes ; drug effects ; physiology ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; pharmacology ; Female ; Male ; Rabbits ; Serum

BACKGROUNDRetinal degenerative diseases are the leading causes of blindness in developed world. Retinal progenitor cells (RPCs) play a key role in retina restoration. Triamcinolone acetonide (TA) is widely used for the treatment of retinal degenerative diseases. In this study, we investigated the role of TA on RPCs in hypoxia condition.

METHODSRPCs were primary cultured and identified by immunofluorescence staining. Cells were cultured under normoxia, hypoxia 6 h, and hypoxia 6 h with TA treatment conditions. For the TA treatment groups, after being cultured under hypoxia condition for 6 h, RPCs were treated with different concentrations of TA for 48-72 h. Cell viability was measured by cell counting kit-8 (CCK-8) assay. Cell cycle was detected by flow cytometry. Western blotting was employed to examine the expression of cyclin D1, Akt, p-Akt, nuclear factor (NF)-κB p65, and caspase-3.

RESULTSCCK-8 assays indicated that the viability of RPCs treated with 0.01 mg/ml TA in hypoxia group was improved after 48 h, comparing with control group (P < 0.05). After 72 h, the cell viability was enhanced in both 0.01 mg/ml and 0.02 mg/ml TA groups compared with control group (all P < 0.05). Flow cytometry revealed that there were more cells in S-phase in hypoxia 6 h group than in normoxia control group (P < 0.05). RPCs in S and G2/M phases decreased in groups given TA, comparing with other groups (all P < 0.05). There was no significant difference in the total Akt protein expression among different groups, whereas upregulation of p-Akt and NF-κB p65 protein expression and downregulation of caspase-3 and cyclin D1 protein expression were observed in 0.01 mg/ml TA group, comparing with hypoxia 6 h group and control group (all P < 0.05).

CONCLUSIONLow-dose TA has anti-apoptosis effect on RPCs while it has no stimulatory effect on cell proliferation.

Animals ; Apoptosis ; drug effects ; physiology ; Caspase 3 ; metabolism ; Cell Cycle ; drug effects ; physiology ; Cell Hypoxia ; drug effects ; physiology ; Cell Proliferation ; drug effects ; physiology ; Cell Survival ; drug effects ; physiology ; Cells, Cultured ; Cyclin D1 ; metabolism ; NF-kappa B ; metabolism ; Proto-Oncogene Proteins c-akt ; metabolism ; Rats ; Rats, Sprague-Dawley ; Retina ; cytology ; Stem Cells ; cytology ; drug effects ; Triamcinolone Acetonide ; pharmacology