Down-regulation of XBP1s alleviates the senescence of renal tubular epithelial cells induced by hypoxia/reoxygenation through Sirt3/SOD2/mtROS signaling pathway / 器官移植

Objective To investigate the role and mechanism of spliced X-box binding protein 1 (XBP1s) in the senescence of primary renal tubular epithelial cells induced by hypoxia/reoxygenation (H/R). Methods Primary renal tubular epithelial cells were divided into the normal control group (NC group), H/R group, empty adenovirus negative control group (Ad-shNC group), targeted silencing XBP1s adenovirus group (Ad-shXBP1s group), empty adenovirus+H/R treatment group (Ad-shNC+H/R group) and targeted silencing XBP1s adenovirus+H/R treatment group (Ad-shXBP1s +H/R group), respectively. The expression levels of XBP1s in the NC, H/R, Ad-shNC and Ad-shXBP1s groups were measured. The number of cells stained with β-galactosidase, the expression levels of cell aging markers including p53, p21 and γH2AX, and the levels of reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD) were determined in the Ad-shNC, Ad-shNC+H/R and Ad-shXBP1s+H/R groups. Chromatin immunoprecipitation was employed to verify Sirtuin 3 (Sirt3) of XBP1s transcription regulation, and the expression levels of Sirt3 and downstream SOD2 after down-regulation of XBP1s were detected. Mitochondrial reactive oxygen species (mtROS) were detected by flow cytometry. Results Compared with the NC group, the expression level of XBP1s was up-regulated in the H/R group. Compared with the Ad-shNC group, the expression level of XBP1s was down-regulated in the Ad-shXBP1s group (both P<0.001). Compared with the Ad-shNC group, the number of cells stained with β-galactosidase was increased, the expression levels of p53, p21 and γH2AX were up-regulated, the levels of ROS, MDA and mtROS were increased, the SOD activity was decreased, the expression level of Sirt3 was down-regulated, and the ratio of Ac-SOD2/SOD2 was increased in the Ad-shNC+H/R group. Compared with the Ad-shNC+H/R group, the number of cells stained with β-galactosidase was decreased, the expression levels of p53, p21 and γH2AX were down-regulated, the levels of ROS, MDA and mtROS were decreased, the SOD activity was increased, the expression level of Sirt3 was up-regulated and the ratio of Ac-SOD2/SOD2 was decreased in the Ad-shXBP1s+H/R group (all P<0.05). Conclusions Down-regulation of XBP1s may ameliorate the senescence of primary renal tubular epithelial cells induced by H/R, which probably plays a role through the Sirt3/SOD2/mtROS signaling pathway.

Mechanism of racanisodamine on alleviating radiation-induced lung injury in mice / 中华放射医学与防护杂志

Objective:To investigate the protective effect of racanisodamine on lung injury in mice exposed to irradiation.Methods:C57BL/6 mice were randomly divided into control group, racanisodamine group, 18 Gy irradiation group (model group) and racanisodamine combined with 18 Gy irradiation group (treatment group), with 5 mice in each group. The mice in the treatment group received racanisodamine (5 mg/kg) intraperitoneally 3 d before irradiation and contained the whole experiments. Then, single chest irradiation of 18 Gy X-rays was performed both in the model and treatment groups. The racanisodamine group and treatment group received racanisodamine intraperitoneally once a day until 6 weeks after irradiation. The mice were killed at 6 weeks after irradiation. The lung histopathology was observed by HE staining. Serum and bronchial alveolar lavage fluid (BALF) inflammatory cytokines such as TNF-α, IL-1β and IL-6 were determined by ELISA method. Cell senescence was detected by SA-β-Gal staining. The expressions of Nrf2, p-Nrf2 and p62 in lung tissue were performed by immunehistochemistry and Western blot assays.Results:Compared with the model group, the scores of HE staining were decreased ( t=8.66, P<0.01), the number of infiltrated inflammatory cells in BALF were decreased ( t=10.70, P<0.01), and protein concentration in BALF had lower levels ( t=6.75, P<0.01), the serum TNF-α, IL-1β and IL-6 were decreased significantly ( t=8.17, 4.58, 6.54, P<0.01), the activity of SA-β-gal was decreased, and the expressions of Nrf2, p-Nrf2 were enhanced ( t=6.42, 7.30, P<0.01), while the expression of p62 was reduced ( t=4.62, P<0.01) in the treatment group. Conclusions:Racanisodamine plays the protective effect of radiation-induced lung injury by alleviating inflammation associating with the activating of Nrf2-related pathway, which reversed radiation-induced cell senescence.

Role of lysosomal damage in senescence of SH-SY5Y cells induced by methylmercury and intervention of melatonin / 环境与职业医学

Background Methylmercury (MeHg) is a neurotoxin, and melatonin (MT) has a protective effect on the nervous system, but whether it can antagonize MeHg-induced nerve cell damage and the associated mechanism remain unknown. Objective Human neuroblastoma cells (SH-SY5Y cells) were used as research objects. A MeHg-induced SH-SY5Y cell senescence model was established to observe autophagy related protein, lysosomal number, and function changes, as well as potential intervention role and associated mechanism of MT. Methods (1) After SH-SY5Y cells were treated with different doses of MeHg (0, 0.125, 0.25, 0.5, 1, 2, and 4 μmol·L−1) for 48 h, the cell viability was detected using a cell viability detection kit (CCK-8 method) and the viability rate was calculated. Senescent cells were detected by an acidic senescence-associated-β-galactosidase (SA-β-gal) staining. (2) A MeHg dose of 0.5 μmol·L−1 that significantly induced senescence of SH-SY5Y cells was screened, and a half and a quarter of the dose (0.25 and 0.125 μmol·L−1) were used for the middle and low dose groups, respectively. (3) In the MT intervention experiments, SH-SY5Y cells were divided into four groups, including control group (0.1% DMSO), MeHg group (0.5 μmol·L−1 MeHg), MT group (1 mmol·L−1 MT), and MT intervention group (1 mmol·L−1 MT+0.5 μmol·L−1 MeHg). In the MT intervention group, cells were exposed to 0.5 μmol·L−1 MeHg for 48 h after 24 h of 1 mmol·L−1 MT pretreatment. (4) SA-β-gal staining was conducted to observe cell senescence; Western blotting for the expression levels of senescence-associated protein p16, autophagy-associated protein p62, LC3Ⅱ, and lysosomal-associated proteins LAMP1, LAMP2, and TFEB; Lyso-Tracker Red for the quantity of lysosomes; LysoSensor Green DND-189 for lysosomal pH changes; electron microscope for the morphological changes of lysosomes. Results The results of CCK-8 indicated that the viability rate of cells decreased with the increase of MeHg exposure concentration. Compared with the control group, the SA-β-gal positive cell ratio in the 0.5 μmol·L−1 MeHg group increased by 48% (P<0.01), p16, p62, as well as LC3Ⅱ protein expressions were significantly increased (P<0.05), LAMP1 and LAMP2 protein levels, as well as the fluorescence intensities of lysosomal red and green fluorescent probes decreased with the increase of MeHg concentration (P<0.05), and the volume of lysosomes increased under the electron microscope. Compared with the MeHg group, the expression of p16 protein was decreased in the 1 mmol·L−1 MT + 0.5 μmol·L−1 MeHg group and the SA-β-gal positive cell ratio was significantly decreased by 19% (P<0.05), the protein levels of p62 and LC3Ⅱ were significantly decreased, the LAMP1 and LAMP2 protein levels and the fluorescence intensities of lysosomal red and green fluorescent probes were increased respectively, the nuclear entry of TFEB was significantly increased, and the differences were statistically significant (P<0.05). Conclusion MeHg may cause cellular senescence by reducing the number of lysosomes and impairing lysosomal activity in SH-SY5Y cells, and MT may ameliorate MeHg-induced lysosomal abnormalities in SH-SY5Y cells, thereby intervening cell senescence.

Lamin B1 regulates the growth of hepatocellular carcinoma cells by influencing telomerase activity / 生物工程学报

Lamin B1 (LMNB1) is highly expressed in liver cancer tissues, and its influence and mechanism on the proliferation of hepatocellular carcinoma cells were explored by knocking down the expression of the protein. In liver cancer cells, siRNAs were used to knock down LMNB1. Knockdown effects were detected by Western blotting. Changes in telomerase activity were detected by telomeric repeat amplification protocol assay (TRAP) experiments. Telomere length changes were detected by quantitative real-time polymerase chain reaction (qPCR). CCK8, cloning formation, transwell and wound healing were performed to detect changes in its growth, invasion and migration capabilities. The lentiviral system was used to construct HepG2 cells that steadily knocked down LMNB1. Then the changes of telomere length and telomerase activity were detected, and the cell aging status was detected by SA-β-gal senescence staining. The effects of tumorigenesis were detected by nude mouse subcutaneous tumorigenesis experiments, subsequent histification staining of tumors, SA-β-gal senescence staining, fluorescence in situ hybridization (FISH) for telomere analysis and other experiments. Finally, the method of biogenesis analysis was used to find the expression of LMNB1 in clinical liver cancer tissues, and its relationship with clinical stages and patient survival. Knockdown of LMNB1 in HepG2 and Hep3B cells significantly reduced telomerase activity, cell proliferation, migration and invasion abilities. Experiments in cells and tumor formation in nude mice had demonstrated that stable knockdown of LMNB1 reduced telomerase activity, shortened telomere length, senesced cells, reduced cell tumorigenicity and KI-67 expression. Bioinformatics analysis showed that LMNB1 was highly expressed in liver cancer tissues and correlated with tumor stage and patient survival. In conclusion, LMNB1 is overexpressed in liver cancer cells, and it is expected to become an indicator for evaluating the clinical prognosis of liver cancer patients and a target for precise treatment.

Characteristics, cellular and molecular mechanisms of renal aging and nutritional intervention strategies / 中华老年医学杂志

Renal aging is a gradual process of degenerative changes in tissue structure and physiological function and is closely related to the occurrence and development of acute kidney injury(AKI)and chronic kidney disease(CKD). The cellular and molecular mechanisms of renal aging mainly include cellular senescence and reduced autophagy, and are regulated by nutritional factors.Promoting reasonable and moderate energy-and protein-restricted diets, strengthening the supervision of food additives and preservatives, cultivating safety awareness of residents, and strictly controlling the daily salt intake are potential nutritional intervention strategies to prevent and delay renal aging.Given the limited number of studies, there is an urgent need to further explore the effectiveness of the above strategies to provide a new evidence-based approach to formulating precise and feasible personalized nutritional intervention programs.

The cell cycle inhibitor P21 promotes the development of pulmonary fibrosis by suppressing lung alveolar regeneration

The cell cycle inhibitor P21 has been implicated in cell senescence and plays an important role in the injury-repair process following lung injury. Pulmonary fibrosis (PF) is a fibrotic lung disorder characterized by cell senescence in lung alveolar epithelial cells. In this study, we report that P21 expression was increased in alveolar epithelial type 2 cells (AEC2s) in a time-dependent manner following multiple bleomycin-induced PF. Repeated injury of AEC2s resulted in telomere shortening and triggered P21-dependent cell senescence. AEC2s with elevated expression of P21 lost their self-renewal and differentiation abilities. In particular, elevated P21 not only induced cell cycle arrest in AEC2s but also bound to P300 and β-catenin and inhibited AEC2 differentiation by disturbing the P300-β-catenin interaction. Meanwhile, senescent AEC2s triggered myofibroblast activation by releasing profibrotic cytokines. Knockdown of P21 restored AEC2-mediated lung alveolar regeneration in mice with chronic PF. The results of our study reveal a mechanism of P21-mediated lung regeneration failure during PF development, which suggests a potential strategy for the treatment of fibrotic lung diseases.

Role of nicotinamide phosphoribosyltransferase in delaying smooth muscle cell senescence and protecting abdominal aortic aneurysm / 中华危重病急救医学

Objective:To investigate the protective effect of nicotinamide phosphoribosyltransferase (NAMPT) on abdominal aortic aneurysm by delaying the senescence of aortic vascular smooth muscle cells (VSMC).Methods:The primary VSMC cells from normal and patients with abdominal aortic aneurysm were cultured by tissue adherence method. Cells were divided into normal human-derived VSMC group (Ctrl-VSMC group), abdominal aortic aneurysm patient-derived VSMC group (AAA-VSMC group), and angiotensinⅡ(AngⅡ) in vitro abdominal aortic aneurysm model group (AngⅡ-VSMC group, 100 nmol/L AngⅡ treated normal human-derived VSMC for 48 hours), AngⅡ+P7C3 group and AAA+P7C3 group after NAMPT agonist P7C3 intervention (adding 5 μmol/L P7C3 on the basis of AngⅡ-VSMC group and AAA-VSMC group, respectively). Immunofluorescence staining was used to identify VSMC; cell proliferation-associated antigen Ki67 staining was used to detect cell proliferation; senescence associated β-galactosidase (SA-β-gal) staining was used to detect cell senescence in each group; Western blotting was used to detect the protein expression levels of senescence-related proteins p21, p16 and NAMPT in each group. Results:Compared with the Ctrl-VSMC group, the positive rate of SA-β-gal staining and the expression levels of senescence-related proteins p21 and p16 in the AAA-VSMC group and AngⅡ-VSMC group were significantly increased [SA-β-gal staining positive rate: (74.1±4.4)%, (68.6±5.5)% vs. (36.8±10.3)%, p21/GAPDH: 0.61±0.07, 0.51±0.03 vs. 0.31±0.03, p16/GAPDH: 0.77±0.03, 0.72±0.06 vs. 0.33±0.26, all P < 0.01]. However, the expression of NAMPT was significantly decreased (NAMPT/GAPDH: 0.88±0.07, 0.79±0.14 vs. 1.29±0.02, both P < 0.01). Compared with the AngⅡ-VSMC group, the positive rate of SA-β-gal staining and the expressions levels of senescence-related proteins p21 and p16 in the AngⅡ+P7C3 group were significantly lower [SA-β-gal staining positive rate: (49.1±3.2)% vs. (68.6±5.5)%, p21/GAPDH: 0.35±0.06 vs. 0.51±0.03, p16/GAPDH: 0.47±0.08 vs. 0.72±0.06, all P < 0.05], while the expression of NAMPT was significantly increased (NAMPT/GAPDH: 1.15±0.06 vs. 0.79±0.14, P < 0.01). Compared with the AAA-VSMC group, the positive rate of SA-β-gal staining and the expression levels of senescence-related proteins p21 and p16 in the AAA+P7C3 group were significantly lower [SA-β-gal staining positive rate: (54.1±6.0)% vs. (74.1±4.4)%, p21/GAPDH: 0.38±0.02 vs. 0.61±0.07, p16/GAPDH: 0.50±0.13 vs. 0.77±0.03, all P < 0.05], but the expression of NAMPT was significantly increased (NAMPT/GAPDH: 1.25±0.28 vs. 0.88±0.07, P < 0.01). Conclusion:NAMPT agonist P7C3 can delay the senescence of VSMC and play a protective role in abdominal aortic aneurysm.

Potential role of brain cell senescence in the pathogenesis of Alzheimer's disease / 药学学报

Cell senescence is characterized by permanent cell cycle arrest, accompanied by the changes in cell metabolism and epigenetic regulation. Alzheimer's disease (AD) is a common neurodegenerative disease, with the main symptoms of memory loss and cognitive impairment. A large number of studies have shown that the senescence of central nervous system cells such as astrocytes and microglia is closely related to the occurrence of AD. Inhibition of brain cell senescence is expected to provide new ideas and therapeutic strategies for the prevention and treatment of AD. This paper reviews the potential roles and mechanisms of senescence of brain cells in AD, and interaction effects among brain cells. This review will provide a new direction for the study of pathological mechanism of AD and the development of anti-AD drugs.

Effects of high-frequency transcranial magnetic stimulation on cellular senescence in Parkinson′s disease / 中华物理医学与康复杂志

Objective:To investigate any anti-aging effect of repeated transcranial magnetic stimulation (rTMS) and explore the relationship between the effect and relief of clinical symptoms in patients with Parkinson′s disease (PD).Methods:A total of 108 PD patients were randomly divided into an rTMS group and a control group, each of 54, while another 54 healthy counterparts were selected to form a normal group. In addition to anti-PD drug therapy, the rTMS group was given daily rTMS treatment, 5 days a week for 4 weeks, while the control group received sham rTMS treatment, with no treatment of the normal group. Before the treatment and after 4 weeks of treatment as well as and 1 month after the ending of the treatment, the subjects′ clinical exercise symptoms were evaluated using the Unified Parkinson′s Disease Rating Scale (UPDRS), a timed exercise test and the 10m re-entry exercise test. Non-exercise symptoms were assessed using the Hamilton Depression Scale (HAMD), the Hamilton Anxiety Scale (HAMA) and the Mini-mental State Examination (MMSE). Fasting venous blood samples were analyzed to quantify the serum levels of tumor necrosis factor (TNF), interleukin-6 (IL-6), interleukin-1β (IL-1β) and matrix metalloproteinase-3 (MMP-3).Results:Four weeks and 1 month after the treatment, the average UPDRS scores, exercise test times and 10m re-entry exercise test results of the rTMS group were significantly better than those before treatment and significantly better than those of the control group at the same time point. The rTMS group′s average HAMA, HAMD and MMSE scores, as well as its average P300 latency and amplitude were also significantly better than those of the control group at the same time point and significantly better than those before treatment. After 4 weeks, the average MMP-3 content in the rTMS group was significantly lower than the control group′s average, and after a month the average levels of TNF, IL-6, IL-1β and MMP-3 of the rTMS group were all significantly different from those before treatment and those of the control group. The TNF, IL-6, IL-1β and MMP-3 levels were all positively correlated with the average UPDRS total score.Conclusion:High-frequency rTMS therapy can change the phenotypes related to cell senescence, and thus has good therapeutic effect on motor and non-motor symptoms of PD.

Effect of Mitochondrial Function on Cell Senescence and Anti-ging Effect of Traditional Chinese Medicine and Moxibustion： A Review / 中国实验方剂学杂志

Since ancient times， delaying aging， health， and longevity have been the universal wish of people. Nowadays， China gives top strategic priority to the development of people's health. How to maintain a healthy life and slow down the aging of the human body is a problem worthy of our attention. Human aging can be shown as cell senescence from the microscopic level. Cell senescence is a process in which cell proliferation and differentiation and physiological function gradually decline. It is a normal physiological function responsible for the removal of damaged cells and is the regeneration and recovery of tissues after injury or acute stress. Aging is an irresistible natural law. Although it is inevitable， it is possible to delay aging. Energy metabolism is an important basis of cell function， in which cells use nutrients such as sugar and fat to produce adenosine triphosphate （ATP）. Mitochondria serve as the cell's power stations， where sugars， fats， and amino acids are eventually oxidized to release energy. Mitochondrial function decreases with age. Changes in mitochondrial dynamics， reactive oxygen species content， autophagy， and metabolites can cause dysfunction of electron transport chain and oxidative phosphorylation， and induce mitochondrial dysfunction. Mitochondrial dysfunction is one of the internal causes of many aging-related diseases， such as neurodegenerative diseases， Alzheimer′s disease， and atherosclerosis. Chinese medicine with few side effects and rich ingredients and health care moxibustion with safety and efficacy have been widely applied to the field of anti-aging. This study reviewed the effect of mitochondrial function on cell senescence， and retrieved， analyzed， and summarized research papers on the mechanism of traditional Chinese medicine （TCM） and moxibustion in delaying aging by affecting mitochondrial function， which is expected to provide new insights for further research in this field.

DNA-PK inhibition by M3814 enhances chemosensitivity in non-small cell lung cancer

A significant proportion of non-small cell lung cancer (NSCLC) patients experience accumulating chemotherapy-related adverse events, motivating the design of chemosensitizating strategies. The main cytotoxic damage induced by chemotherapeutic agents is DNA double-strand breaks (DSB). It is thus conceivable that DNA-dependent protein kinase (DNA-PK) inhibitors which attenuate DNA repair would enhance the anti-tumor effect of chemotherapy. The present study aims to systematically evaluate the efficacy and safety of a novel DNA-PK inhibitor M3814 in synergy with chemotherapies on NSCLC. We identified increased expression of DNA-PK in human NSCLC tissues which was associated with poor prognosis. M3814 potentiated the anti-tumor effect of paclitaxel and etoposide in A549, H460 and H1703 NSCLC cell lines. In the four combinations based on two NSCLC xenograft models and two chemotherapy, we also observed tumor regression at tolerated doses

Metformin inhibits the senescence and senescence-associated secretory phenotype of gastric cancer BGC823 cells induced by doxorubicin / 中国肿瘤生物治疗杂志

@#[Abstract] Objective: To investigate the effect of metformin on the senescence-associated secretory phenotype (SASP) of doxorubicin-induced gastric cancer BGC823 cells. Methods: Human gastric cancer BGC823 cells were cultured in vitro and treated with doxorubicin at gradient concentrations (50, 100, 150 and 200 nmol/L). Cell senescence was detected by SA-β-gal staining, and SASP factor expression was detected by ELISA. The effects of metformin on cell senescence and SASP factor secretion induced by doxorubicin (100 nmol/L) were observed by adding gradient concentrations of metformin (0, 5, 10 and 20 mmol/L). Results: With the increase of doxorubicin concentration and treatment time, the senescence rate of gastric cancer BGC823 cells increased first and then decreased. At 96 h after 100 nmol/L doxorubicin treatment, the peak aging rate reached 68.7%, accompanied with significantly increased expressions of SASP factors IL-1a, IL-6, IL-8 and CXCL1. The proportion of senescent cells was (55.2±1.9)%, (48.7±2.2)% and (40.8±2.3)% respectively under the effects of 5, 10 and 20 mmol/L metformin, which was significantly lower than that in the non-metformin treatment group (P< 0.01). At the same time, with the increase of metformin concentration, the production of SASP factors IL-1α, IL-6, IL-8 and CXCL1 showed a gradient decline. Compared with the non-metformin treatment group, IL-6 and IL-8 decreased significantly under the effect of metformin above 10 mmol/L (P<0.05 or P<0.01), while IL-1α and CXCL1 decreased significantly under the effect of 20 mmol/L metformin (all P<0.05). Conclusion: Metformin can inhibit the senescence and SASP production of gastric cancer cells induced by doxorubicin.

Guilu Erxian Glue () Inhibits Chemotherapy-Induced Bone Marrow Hematopoietic Stem Cell Senescence in Mice May via p16 / 中国结合医学杂志

OBJECTIVE@#To evaluate the effect of Guilu Erxian Glue (, GEG) on cyclophosphamide (CTX)-induced bone marrow hematopoietic stem cells (HSCs) senescence in mice and explore the underlying mechanism.@*METHODS@#The H@*RESULTS@#Compared with the model group, GEG increased cell viability as well as proliferation (P<0.05 or P<0.01) and reduced β -gal expression. Furthermore, GEG significantly decreased the expressions of p16@*CONCLUSION@#GEG can alleviate CTX-induced HSCs senescence in mice, and the p16

Mechanism of Bushen Huayu Shengxin Decoction in Delaying Senescence of Bone Marrow Mesenchymal Stem Cells by Improving Ischemic-hypoxic Microenvironment / 中国实验方剂学杂志

Objective:To explore the mechanism of Bushen Huayu Shengxin decoction in delaying senescence of bone mesenchymal stem cells(BMSCs) by improving cellular microenvironment and regulating p16/pRb and p53/p21 signaling pathways. Method:The cells were cultured in serum-free 1640 medium and hypoxic cell workstation for 24 hours to establish the cell model of ischemic-hypoxic microenvironment in vitro, then randomized into control group (with complex medium), model group (with complete medium), and treatment group (with serum medium-containing Bushen Huayu Shengxin decoction), and all were cultured in hypoxic cell workstation for 24 hours. The normal group was added with control culture for complete medium, The cell cycle of BMSCs was detected by flow cytometry, the expressions of p16INK4a, p53, p21 and Survivn, cysteine aspartic acid protease-3 (Caspase-3), polyadenosine diphosphate ribose polymerase (PARP) mRNA were analyzed by Real-time fluorescence quantitative polymerase chain reaction (Real-time PCR), and the levels of β-catenin protein and glycogen synthase kinase-3β（GSK-3β） protein were detected by Western blot. Result:Compared with the normal group, the proportion of S phase cells increased, while that at the G0/G1 phase decreased significantly in the model group (P<0.05). Compared with the model group, the proportion of S phase decreased, whereas that at the G0/G1 phase gradually increased in the treatment group (P<0.05). Compared with the normal group, mRNA expressions of p16INK4a, p53, p21 and Survivn, Caspase-3, PARP in the model group increased significantly (P<0.05). Compared with the model group, mRNA expressions of p16INK4a, p53, p21 and Survivn, Caspase-3, PARP in the treatment group decreased significantly (P<0.05). Compared with the normal group, protein expressions of β-catenin and GSK-3β in the model group increased significantly (P<0.05). Compared with the model group, protein expressions of β-catenin and GSK-3β in the treatment group decreased significantly (P<0.05). Conclusion:Bushen Huayu Shengxin decoction could delay the senescence of BMSCs by improving ischemic-hypoxic microenvironment and regulating p16/pRb and p53/p21 signaling pathways.

Interventional Effect and Mechanism of Extract of Ginseng Radix et Rhizoma, Notoginseng Radix et Rhizoma and Chuanxiong Rhizoma on Vascular Endothelial Cellular Senescence Induced by High Glucose and High Fat / 中国实验方剂学杂志

Objective: To explore the mechanism of extract of Ginseng Radix et Rhizoma, Notoginseng Radix et Rhizoma and Chuanxiong Rhizoma in delaying the senescence of vascular endothelial cells induced by high glucose and high fat. Method: The 40 mmol·L-1 glucose and 100 μmol·L-1 palmitate were used to induce endothelial cell senescence. The experiment was divided into control group, model group and low, medium and high-dose traditional Chinese medicine groups (50,100,200 mg·L-1). The intervention lasted for 48 h. Cell proliferation was detected by cell counting kit-8(CCK-8); cell senescence was detected by senescence β-galactosidase staining; p16 and p21 protein expression levels were detected by Western blot; p-H2A. X(Ser139) expression, mitochondria ROS(mtROS) production and changes in mitochondrial membrane potential(MMP) were detected by immunofluorescence. Result: Compared with the control group, in model group, the cell proliferation ability and the number of SA-β-gal blue-stained cells decreased(PPPPβ-gal blue-stained cells, the mtROS production, and expression levels of p16, p21 and p-H2A. X(Ser139)(PPConclusion: The above results suggest that extract of Ginseng Radix et Rhizoma, Notoginseng Radix et Rhizoma and Chuanxiong Rhizoma delay of endothelial cellular senescence induced by high glucose and high fat, and its mechanism may be related to increasing mitochondrial membrane potential and reducing DNA damage accumulation caused by ROS production.

ECRG4: a new potential target in precision medicine / 医学前沿

Given the rapid development in precision medicine, tremendous efforts have been devoted to discovering new biomarkers for disease diagnosis and treatment. Esophageal cancer-related gene-4 (ECRG4), which is initially known as a new candidate tumor suppressor gene, is emerging as a sentinel molecule for gauging tissue homeostasis. ECRG4 is unique in its cytokine-like functional pattern and epigenetically-regulated gene expression pattern. The gene can be released from the cell membrane upon activation and detected in liquid biopsy, thus offering considerable potential in precision medicine. This review provides an updated summary on the biology of ECRG4, with emphasis on its important roles in cancer diagnosis and therapy. The future perspectives of ECRG4 as a potential molecular marker in precision medicine are also discussed in detail.

Effect of rhizoma polygonati on functional activity of endothelial progenitor cells to delay senescense via decrease of ros / 中国药理学通报

Aim To investigate the effect of Rhizoma Polygonati( RP) on the functional activity and the level of reactive oxygen species (ROS) on the subculture of endothelial progenitor cells ( EPCs) in aging rats. Methods EPCs from bone marrow in rats were isolated and cultured in vitro and identified. The 2nd EPCs were divided into fourgroups, which were subcultured to the 4th, 6th and 8th passage with application of drug - serum containing RP or not. The positive rate of cell senescence was detected by beta - galactosidase, the proliferation, migration and tubule formation were assayed by MIT, transwell chamber and in vivo angio- gcnesis kit, respectively, and ROS level was detected by flow cytometry. Results In the process of EPCs subculture, the positive rate of cell senescence gradually increased, accompanied by a significant decrease in proliferation, migration and tubule formation. The level of ROS increased sharply (P<0. 05). RP could reduce the positive rate of cell senescence, enhance the functional activities, and decrease the level of ROS of EPCs significantly (P < 0. 05). Conclusions RP may delay the aging process of EPCs in vitro and protect the function of EPCs by decreasing the level of ROS.

Effect of microRNA-34a/SIRT1/p53 signal pathway on notoginsenoside R₁ delaying vascular endothelial cell senescence / 中国中药杂志

This study aimed to investigate the effect of notoginsenoside R₁ in delaying H₂O₂-induced vascular endothelial cell senescence through microRNA-34a/SIRT1/p53 signal pathway. In this study， human umbilical vein endothelial cells(HUVECs) were selected as the study object; the aging model induced by hydrogen peroxide(H₂O₂) was established， with resveratrol as the positive drug. HUVECs were randomly divided into four groups， youth group， senescence model group， notoginsenoside R₁ group and resveratrol group. Notoginsenoside R₁ group and resveratrol group were modeled with 100 μmoL·L⁻¹ H₂O₂ for 4 h after 24 h treatment with notoginsenoside R₁(30 μmoL·L⁻¹) and resveratrol(10 μmoL·L⁻¹) respectively. At the end， each group was cultured with complete medium for 24 h. The degree of cellular senescence was detected by senescence-associated β-galactosidase(SA-β-Gal) staining kit， the cell viability was detected by cell counting kit-8， the cell cycle distribution was analyzed by flow cytometry， and the cellular SOD activity was detected by WST-1 method in each group. The expressions of SIRT1， p53， p21 and p16 proteins in HUVECs were detected by Western blot. In addition， the mRNA expressions of miRNA-34a， SIRT1 and p53 in HUVECs were assayed by Real-time PCR. These results indicated that notoginsenoside R₁ significantly reduced the positive staining rate of senescent cells， enhanced the cell proliferation capacity and intracellular SOD activity， decreased the proportion of cells in G₀/G₁ phase， and increased the percentage of cells in S phase simultaneously compared with the senescence model group. Moreover， notoginsenoside R₁ decreased the mRNA expressions of miRNA-34a and p53 and the protein expression of p53， p21 and p16.At the same time， notoginsenoside R₁ increased the protein and mRNA expressions of SIRT1. The differences in these results between the senescence model group and the notoginsenoside R₁ group were statistically significant(<0.05). However， there was not statistically significant difference in these results between the notoginsenoside R₁ group and the resveratrol group. In conclusion， the senescence of endothelial cells induced by H₂O₂ can be used as a model for studying aging. Notoginsenoside R₁ has an obvious anti-aging effect on vascular endothelial cells in this study. The possible mechanism is that notoginsenoside R₁ can delay the senescence process of vascular endothelial cells induced by H₂O₂ by regulating microRNA-34a/SIRT1/p53 signal pathway.

The effects of leptin on the senescence of bone marrow-derived mesenchymal stem cells, frequencies of immune cells and lupus disease in MRL/Ipr mice / 中华风湿病学杂志

Objective To explore the effects of leptin on the senescence of bone marrow-derived mesenchymal stem cells,frequencies of Treg and Th17 cells,and lupus disease in MRL/lpr mice,and to explore the pathogenesis of systemic lupus erythematosus (SLE).Methods Leptin (1 μg/g) or phosphate buffer saline (PBS) was injected into C57BL/6 (B6) mice,ob/ob mice and MRL/lpr mice intra-peritoneally.Urine protein was examined by Coomassie brilliant blue method.The levels of serum leptin,antinuclear antibody (ANA),anti-dsDNA antibody and immunoglobulin (Ig)G were detected by enzyme linked immunosorbent assay (ELISA).Bone marrow derived mesenchymal stem cells (MSCs) were isolated,and treated with or without leptin,then the senescence of MSCs were evaluated by SA-β-gal staining,the levels of p53 and p21 mRNA were measured by real time polymerase chain reaction (PCR),the protein levels of p53 and p21 were tested by Westem blotting method.Data were analyzed with t test and ANOVA.Results The level of serum leptin was higher in MRL/lpr mice than that of B6 mice [(4.5±0.8) ng/ml vs (2.3±0.5) ng/ml,t=2.38,P＜0.05].Leptin treatment in vivo accelerated the senescence of bone marrow-derived MSCs from all B6 mice,lupus mice and ob/ob mice,manifestedas increased frequencies of SA-β-gal positive cells [(20.6±0.6)％ vs (15.4±1.6)％,t=8.09,P＜0.05],higher levels of mRNA and p53 and p21 protein.Leptin treatment in vivo also down-regulated the frequency of Treg cells [(2.77±0.23)％ vs (5.01±0.18)％ t=3.91,P＜0.01],and up-regulated Th17 cells [(2.24± 0.11)％ vs (1.74±0.07)％,t=5.013,P＜0.01].The titer of ANA was further increased in leptin-treated MRL/lpr mice [(288±69) U/ml vs (190±90) U/ml,t=2.84,P＜0.05].The levels of serum anti-dsDNA antibody were also remarkably elevated [(12 399±1 237) U/ml vs (6 217±1 304) U/ml,t=3.44,P＜0.01].Leptin could increase the secretion of total IgG [MRL/Ipr (27.2±2.9) mg/ml vs (25.0±3.3) mg/ml,t=3.07,P＜0.05].The proteinuria concentration was increased in lupus mice [(1.00±0.10) mg/ml vs (0.81 ±0.06) mg/ml,t=3.31,P＜0.05],demonstrating that leptin accelerates lupus nephritis.Conclusion Leptin administr-ation in vivo enhances the senescence of bone marrow derived MSCs,dys-regulate of Treg/Th17 cells from MRL/Ipr mice,which impaires the role of immuno-modulation,and aggravates the progress of lupus disease.

Senescence-associated secretory phenotype and its complex regulation networks: A review of molecular mechanisms / 第二军医大学学报

Cellular senescence is a state of permanent growth arrest characterized by an irreversible exit from the cell cycle and the secretion of senescence-associated secretory phenotype (SASP). The secretory process of SASP can be roughly divided into three steps: DNA damage response (DDR)-rapid paracrine, early and mature stages. The complex molecular regulation mechanisms of SASP involve DDR, p38 mitogen-activated protein kinase (MAPK) signal pathway, activation of nuclear factor κB (NF-κB) and CCAAT/enhancer-binding protein β (C/EBPβ), epigenetic alterations of SASP gene, posttranscriptional regulation of gene and autophagy. SASP regulates a variety of pathological states caused by microenvironment changes and has been a drug target to regulate the aging effect, which providing a new therapeutic method for tumor and agerelated pathological states. In this paper, we classified the different types of SASP, reviewed the role of SASP in biological processes and discussed the related molecular mechanisms.