Apolipoprotein E (ape E) has three common alleles (ape epsilon 2, epsilon 3 and epsilon 4) that code for three major isoforms E2, E3 and E4. The isoforms differ from each other by a single amino acid substitutions at two positions and also differ in their binding affinity for the apo E receptors. Moreover, recently a strong association between the apo epsilon 4 allele and late-onset Alzheimer disease (AD) was demonstrated. In this study, were analyzed the apo E genotypes using the Hhal digestion of PCR amplified samples, and the apo epsilon 4 allele frequency from 70 AD patients and 106 normal population in Korea. The results suggested that the frequency of epsilon 4 allele among the AD patients (35.7%) was 3 times higher than that among the control population (13.7%). The data, which are in agreement with recent reports, suggests that the apo epsilon 4 allele is associated with AD in Korea.
Alleles ; Alzheimer Disease* ; Amino Acid Substitution ; Apolipoproteins E ; Apolipoproteins* ; Digestion ; Gene Frequency ; Genotype ; Humans ; Korea ; Low Density Lipoprotein Receptor-Related Protein-1 ; Polymerase Chain Reaction ; Protein Isoforms

Objective: To uncover the time-dependent expression pattern of ptk2b gene and ptk2b-encoded protein, protein tyrosine kinase 2 beta(PTK2B), in the brain tissues of transgenic animal models of Alzheimer's disease (AD) and its relationship with the levels of Aβ_1-42, phosphorylation of Tau (p-Tau) and low density lipoprotein receptor-related protein-1(LRP-1) in blood and brain tissues. Methods: In this study, 5-, 10- and 15-month-old APPswe/PS1dE9 double-transgenic mice harboring the genotype of AD confirmed by the gene test were divided into the 5-, 10- and 15-month-old experiment groups, and simultaneously, age-matched C57BL/6J mice were placed into the corresponding control groups, with 8 mice in each group. All mice were subjected to the Morris Water Maze for test of cognitive and behavioral ability. Expression profiles of PTK2B, Aβ_1-42, p-Tau/Tau and LRP-1 in the hippocampus or blood of mice were quantified by using the immunohistochemistry staining, Western blot or enzyme-linked immunosorbent assay (ELISA), while the mRNA expression of ptk2b in the hippocampus was quantified by using the real-time quantitative polymerase chain reaction (qRT-PCR). Results: Results of experiment groups demonstrated that as mice aged, the expression levels of PTK2B, ptk2b mRNA, Aβ_1-42 and p-Tau/Tau in the hippocampus were increased, and the expression of LRP-1 was decreased gradually. While in the blood, the level of Aβ_1-42 was decreased, and the cognitive and behavioral ability was decreased in an age-dependent manner (all P＜ 0.05). However, comparisons among the control groups, only the age-dependent downregulation of LRP-1 were observed in hippocampus(P＜0.05), but other indicators had no significant differences (P＞0.05). Conclusion: In the hippocampus of APP/PS1 double-transgenic mice, the expressions of PTK2B, Aβ_1-42 and p-Tau/Tau are upregulated, LRP-1 is downregulated, while cognitive and behavioral ability is decreased, and such changes are presented in a time-dependent manner.
Alzheimer Disease/metabolism* ; Amyloid beta-Peptides ; Amyloid beta-Protein Precursor/genetics* ; Animals ; Focal Adhesion Kinase 2/metabolism* ; Hippocampus/metabolism* ; Low Density Lipoprotein Receptor-Related Protein-1 ; Maze Learning ; Mice ; Mice, Inbred C57BL ; Mice, Transgenic ; RNA, Messenger

OBJECTIVETo explore the effect of peimine on excision repair cross-complementation 1 (ERCC1) mRNA and lung resistant protein (LRP) expressions in A549/cisplatin (DDP) multidrug resistance (MDR) cell line.

METHODSLung cancer A549/DDP cells were cultured in vitro.Cells at logarithmic growth phase were divided into 4 groups, i.e., the blank control group, the DDP group, the ligustrazine group (DDP+ligustrazine), the peimine group (DDP + peimine). After 48-h drug action, ERCC1 mRNA expression was detected by RT-PCR and LRP expression detected by cell immunofluorescence.

RESULTSThere was no statistical difference in expression levels of ERCC1 mRNA and LRP between the DDP group and the blank control group (P > 0.05). Compared with the DDP group, expression levels of ERCC1 mRNA and LRP obviously decreased in the ligustrazine group and the peimine group (P < 0.05). They were obviously lower in the peimine group than in the ligustrazine group (P < 0.05).

CONCLUSIONSPeimine could reverse MDR of A549/DDP cell line. Its mechanism might be associated with down-regulating ERCC1 mRNA and LRP expression levels.

Cell Line, Tumor ; Cevanes ; pharmacology ; Cisplatin ; DNA-Binding Proteins ; genetics ; Down-Regulation ; Drug Resistance, Multiple ; Drug Resistance, Neoplasm ; drug effects ; Endonucleases ; genetics ; Humans ; Low Density Lipoprotein Receptor-Related Protein-1 ; genetics ; Lung Neoplasms ; RNA, Messenger ; metabolism

OBJECTIVETo investigate the relationship between the low density lipoprotein receptor-related protein gene (LRP) 766C/T polymorphisms and Alzheimer's disease (AD) in Xinjiang Uygurs and Hans populations.

METHODSThose included in the study were > or = 50 years of age and of either Xinjiang Uygur or Han descents. Two hundred and nine individuals had AD and 220 were healthy controls. They were recruited according to ADRDA-NINCDS criteriaîThe polymorphisms of the LRP gene were determined by the PCR-restriction fragment length polymorphism technique. The case-control analysis was adopted to analyze the frequencies of genotypes and alleles.

RESULTS(1) The distribution of genotypes or alleles of LRP gene had significant differences between the AD group and the control group in both the Xinjiang Uygurs and Hans populations (P < 0.05). (2) The frequencies of genotypes and alleles were significantly different between the Han AD and Han control group (P < 0.05). (3) The frequencies of genotypes and alleles in those > or = 65 years were significantly different from that in others (P < 0.05). There was a significant increase of AD in the C allele carriers (OR=1.98, P < 0.05). (4) The frequencies of the CC genotype and C allele in female AD patients were higher than that in female controls (P < 0.05), and the C allele carriers had significant increase of AD (OR=2.927, P < 0.05).

CONCLUSIONThe LRP 766C/T polymorphisms were significantly different between the Chinese Xinjiang Uygur and Han populations. The LRP 766C/T polymorphisms might be associated with AD in the Han population, in females and those of > or = 65 years old.

Alleles ; Alzheimer Disease ; genetics ; Asian Continental Ancestry Group ; ethnology ; genetics ; Ethnic Groups ; genetics ; Female ; Genotype ; Humans ; Low Density Lipoprotein Receptor-Related Protein-1 ; genetics ; Male ; Middle Aged ; Polymorphism, Genetic

BACKGROUND: Fibrous hamartoma is the key pathology of congenital pseudarthrosis of the tibia (CPT), which was shown to have low osteogenicity and high osteoclastogenicity. This study further investigated the mechanism of impaired osteoblastic differentiation of fibrous hamartoma cells. METHODS: Fibroblast-like cells were obtained from enzymatically dissociated fibrous hamartomas of 11 patients with CPT associated with neurofibromatosis type I (NF1). Periosteal cells were also obtained from the distal tibial periosteum of 3 patients without CPT or NF1 as control. The mRNA levels of Wnt ligands and their canonical receptors, such as Lrp5 and beta-catenin, were assayed using reverse transcriptase PCR (RT-PCR). Changes in mRNA expression of osteoblast marker genes by rhBMP2 treatment were assayed using quantitative real time RT-PCR. Changes in mRNA expression of transcription factors specifically involved in osteoblastic differentiation by rhBMP2 treatment was also assayed using quantitative real-time RT-PCR. RESULTS: Wnt1 and Wnt3a mRNA expression was lower in fibrous hamartoma than in tibial periosteal cells, but their canonical receptors did not show significant difference. Response of osteoblastic marker gene expression to rhBMP2 treatment showed patient-to-patient variability. Col1a1 mRNA expression was up-regulated in most fibrous hamartoma tissues, osteocalcin was up-regulated in a small number of patients, and ALP expression was down-regulated in most fibrous hamartoma tissues. Changes in mRNA expression of the transcription factors in response to rhBMP2 also showed factor-to-factor and patient-to-patient variability. Dlx5 was consistently up-regulated by rhBMP2 treatment in all fibrous hamartoma tissues tested. Msx2 expression was down-regulated by rhBMP2 in most cases but by lesser extent than control tissue. Runx2 expression was up-regulated in 8 out of 18 fibrous hamartoma tissues tested. Osterix expression was up-regulated in 2 and down-regulated in 3 fibrous hamartoma tissues. CONCLUSIONS: Congenital pseudarthrosis of the tibia appears to be caused by fibrous hamartoma originating from aberrant growth of Nf1 haploinsufficient periosteal cells, which failed in terminal osteoblastic differentiation and arrested at a certain stage of this process. This pathomechanism of CPT should be targeted in the development of novel therapeutic biologic intervention.
Adolescent ; *Cell Differentiation ; Cells, Cultured ; Child ; Child, Preschool ; Female ; Hamartoma/complications/*pathology ; Humans ; Infant ; Low Density Lipoprotein Receptor-Related Protein-5/metabolism ; Male ; Neurofibromatosis 1/complications/*pathology ; Osteoblasts/*pathology ; Periosteum/pathology ; Pseudarthrosis/complications/*congenital/pathology/physiopathology ; Receptors, Wnt/metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Tibia/*pathology ; Transcription Factors/metabolism ; Wnt1 Protein/metabolism ; Wnt3A Protein/metabolism ; beta Catenin/metabolism

OBJECTIVE: To investigate the role of Numb in regulating mammalian target of rapamycin (mTOR) complex 1 (mTORC1) signaling pathway. METHODS: Male BALB/C mouse models of acute kidney injury (AKI) were subjected to intravenous injections of Numb-siRNA or NC-siRNA with or without intraperitoneal cisplatin injections. After the treatments, the expressions and distribution of Numb and megalin in the renal tissues of the mice were detected with immunohistochemistry, and the renal expressions of Numb, S6, p-S6, S6K1, p-S6K1, 4EBP1 and p-4EBP1 were examined with Western blotting. The proximal renal tubular epithelial cells were isolated from the mice transfected with Numb-siRNA for in vitro culture. In NRK-52E cells, the effects of amino acid stimulation, Numb knockdown, and V1G1 overexpression, alone or in combination, on expressions of Numb, S6 and p-S6 were detected with Western blotting; the expressions of AMPK and p-AMPK were also detected in transfected NRK-52E cells, mouse kidneys and cultured mouse renal tubular epithelial cells. RESULTS: In BALB/C mice, injection of Numb-siRNA caused significant reductions of Numb and p-S6 expressions without affecting megalin expression in the renal proximal tubules (P < 0.05). Cisplatin treatment obviously upregulated p-S6K1 and p-4EBP1 expressions in the kidneys of the mice (P < 0.05), and this effect was significantly inhibited by treatment with Numb-siRNA (P < 0.05). In NRK-52E cells, amino acid stimulation significantly upregulated the expression of p-S6 (P < 0.05), which was strongly suppressed by transfection with Numb-siRNA (P < 0.05). Numb knockdown inhibited AMPK activation in NRK-52E cells, mouse kidneys and primary proximal tubular epithelial cells (P < 0.05). Numb knockdown significantly downregulated V1G1 expression in NRK-52E cells (P < 0.05), and V1G1 overexpression obviously reversed the inhibitory effect of Numb-siRNA on S6 phosphorylation (P < 0.05). CONCLUSION Numb promotes the activation of mTORC1 signaling in proximal tubular epithelial cells by upregulating V1G1 expression.
Animals ; Male ; Mice ; Amino Acids/pharmacology* ; AMP-Activated Protein Kinases/metabolism* ; Cisplatin/pharmacology* ; Epithelial Cells ; Low Density Lipoprotein Receptor-Related Protein-2/metabolism* ; Mammals/metabolism* ; Mechanistic Target of Rapamycin Complex 1/metabolism* ; Membrane Proteins/metabolism* ; Mice, Inbred BALB C ; Nerve Tissue Proteins/metabolism* ; RNA, Small Interfering/metabolism* ; Signal Transduction ; Vacuolar Proton-Translocating ATPases/metabolism*