1.Time dependent expression profiling of PTK2B and its relationship with Aβ, Tau and LRP-1 in hippocampus and blood of APPswe/PS1dE9 double-transgenic mouse.
Kai-Min HAO ; Zhen LIU ; Hao-Yu WANG ; Wen-Xiu QI
Chinese Journal of Applied Physiology 2022;38(1):17-24
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 Aβ1-42, 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, Aβ1-42, 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, Aβ1-42 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 Aβ1-42 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, Aβ1-42 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*
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Amyloid beta-Peptides
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Amyloid beta-Protein Precursor/genetics*
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Animals
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Focal Adhesion Kinase 2/metabolism*
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Hippocampus/metabolism*
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Low Density Lipoprotein Receptor-Related Protein-1
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Maze Learning
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Mice
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Mice, Inbred C57BL
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Mice, Transgenic
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RNA, Messenger
2.Numb activates the mTORC1 signaling pathway in proximal tubular epithelial cells by upregulating V1G1 expression.
Ze LIU ; Da YOU ; Yong LI ; Yong Mei HE ; A Fang LI ; Pan LI ; Chun Yan LI
Journal of Southern Medical University 2022;42(10):1462-1469
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
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Male
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Mice
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Amino Acids/pharmacology*
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AMP-Activated Protein Kinases/metabolism*
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Cisplatin/pharmacology*
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Epithelial Cells
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Low Density Lipoprotein Receptor-Related Protein-2/metabolism*
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Mammals/metabolism*
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Mechanistic Target of Rapamycin Complex 1/metabolism*
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Membrane Proteins/metabolism*
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Mice, Inbred BALB C
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Nerve Tissue Proteins/metabolism*
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RNA, Small Interfering/metabolism*
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Signal Transduction
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Vacuolar Proton-Translocating ATPases/metabolism*
3.Effects of compound Shenhua tablet on renal tubular Na+-K+-ATPase in rats with acute ischemic reperfusion injury.
Yue YANG ; Ri-bao WEI ; Xiao-yong ZHENG ; Qiang QIU ; Shao-yuan CUI ; Zhong YIN ; Suo-zhu SHI ; Xiang-mei CHEN
Chinese journal of integrative medicine 2014;20(3):200-208
OBJECTIVETo observe the effect of Compound Shenhua Tablet (, SHT) on the sodium-potassium- exchanging adenosinetriphosphatase (Na(+)-K(+)-ATPase) in the renal tubular epithelial cells of rats with acute ischemic reperfusion and to investigate the mechanisms underlying the effects of SHT on renal ischemic reperfusion injury (RIRI).
METHODSFifty male Wistar rats were randomly divided into the sham surgery group, model group, astragaloside group [150 mg/(kg·d)], SHT low-dose group [1.5 g/(kg·d)] and SHT high-dose group [3.0 g/(kg·d)], with 10 rats in each group. After 1 week of continuous intragastric drug administration, surgery was performed to establish the model. At either 24 or 72 h after the surgery, 5 rats in each group were sacrificed, blood biochemistry, renal pathology, immunoblot and immunohistochemical examinations were performed, and double immunofluorescence staining was observed under a laser confocal microscope.
RESULTSCompared with the sham surgery group, the serum creatinine (SCr) and blood urea nitrogen (BUN) levels were significantly increased, Na(+)-K(+)-ATPase protein level was decreased, and kidney injury molecule-1 (KIM-1) protein level was increased in the model group after the surgery (P<0.01 or P<0.05). Compared with the model group, the SCr, BUN, pathological scores, Na(+)-K(+)-ATPase, and the KIM-1 protein level of the three treatment groups were significantly improved at 72 h after the surgery (P<0.05 or P<0.01). And the SCr, BUN of the SHT low- and high-dose groups, and the pathological scores of the SHT high-dose group were significantly lower than those of the astragaloside group (P<0.05). The localizations of Na(+)-K(+)-ATPase and megalin of the model group were disrupted, with the distribution areas overlapping with each other and alternately arranged. The severity of the disruption was slightly milder in three treatment groups compared with that of the model group. The results of immunofluorescence staining showed that the SHT high-dose group had a superior effect as compared with the astragaloside group and the SHT low-dose group.
CONCLUSIONSThe SHT effectively alleviated RIRI caused by ischemic reperfusion, promoted the recovery of the polarity of renal tubular epithelial cells, and protected the renal tubules. The therapeutic effects of SHT were superior to those of astragaloside as a single agent.
Acute Disease ; Animals ; Blood Urea Nitrogen ; Cell Adhesion Molecules ; metabolism ; Chromatography, Liquid ; Creatinine ; blood ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Fluorescent Antibody Technique ; Immunoblotting ; Kidney Function Tests ; Kidney Tubules ; blood supply ; drug effects ; enzymology ; pathology ; Low Density Lipoprotein Receptor-Related Protein-2 ; metabolism ; Male ; Rats ; Rats, Wistar ; Reperfusion Injury ; drug therapy ; enzymology ; pathology ; Saponins ; analysis ; Sodium-Potassium-Exchanging ATPase ; metabolism ; Staining and Labeling ; Tablets