AIM: To investigate the effects of high-concentration glucose on the cell viability of retinal pigment epithelialcells(ARPE-19)/ human umbilical vein endothelial cells(HUVEC)cells, as well as on the expression levels of sirtuin 6(SIRT6).

METHODS:ARPE-19 and HUVEC cells were cultured for 48 h in media containing various glucose concentrations(5.5, 25, 50, 75, 100 mmol/L)and cellular morphology was observed under an optical microscope.Cell viability was assessed using the CCK-8 assay. Flow cytometry was utilized to evaluate apoptosis levels, and Western blot analysis was conducted to measure the expression of Bcl-2 and SIRT6. ARPE-19/HUVEC cells were treated with 50 mmol/L glucose for 48 h, after which immunofluorescence staining was performed to determine the subcellular localization and expression level of SIRT6 protein. In parallel, cells receiving the same treatment were harvested at different time points(0, 6, 12, 24, 36, 48, and 72 h), and the temporal changes in SIRT6 protein expression were assessed by Western blot analysis. SIRT6 overexpressing stable ARPE-19/HUVEC cell lines were constructed. Western blot was performed to detect the effects of SIRT6 overexpression on the expression levels of glucose transporters in ARPE-19/HUVEC cells treated with high glucose(50 mmol/L glucose).

RESULTS:Compared with the 5.5 mmol/L glucose group, cell number was decreased and cell viability was significantly reduced in ARPE19/HUVEC cells with increasing glucose concentrations(all P<0.01). Meanwhile, the protein expression level of SIRT6 was markedly downregulated(P<0.05). Such inhibitory effects exhibited both concentration-and time-dependent patterns(all P<0.05). Furthermore, high glucose induced cell apoptosis and downregulated the protein expression of Bcl-2(P<0.05). Immunofluorescence staining revealed that SIRT6 protein was predominantly localized in the nucleus after 48 h of high-glucose treatment, accompanied by pyknosis and nuclear fragmentation. After incubation with highg-lucose medium(50 mmol/L glucose)for different durations, long-term high-glucose intervention was found to reduce SIRT6 protein expression in ARPE19/HUVEC cells. Successful construction of the SIRT6-overexpressing stable ARPE-19/HUVEC cell lines was confirmed via immunofluorescence and Western blotting. Western blot analysis revealed that, compared with the HG+LV-con group, the HG+LV-SIRT6 group exhibited no significant differences in GLUT1 or GLUT4 expression in ARPE-19 cells, whereas GLUT3 expression was elevated(P<0.05). Compared with the HG+LV-con group, the HG+LV-SIRT6 group showed no significant change in GLUT1 expression, while GLUT3 and GLUT4 levels were increased(both P<0.05).

CONCLUSION:High-concentration glucose-reduce the proliferative activity of ARPE-19/HUVEC cells, induce apoptosis, and downregulate SIRT6 expression. SIRT6 may alleviate high glucose-induced retinal cell damage by promoting the expression of glucose transporters.

The prevalence rate of nonalcoholic fatty liver disease(NAFLD)reaches up to 30%around the world,and the disease has a serious impact on human health and constitutes a public health burden.Due to difficulties in the diagnosis and monitoring of NAFLD,it is important to identify potential drug targets and biomarkers,and multi-omics techniques hold great promise in the search for early diagnostic markers,therapeutic targets,and outcome and prognostic assessment of NAFLD.This article reviews the research advances in multi-omics techniques in the field of NAFLD in recent years,in order to provide a richer theoretical basis and new strategies for the prevention and treatment of NAFLD.

Objective:To systematically understand the reform progress of disease prevention and control system in China.Methods:The literature regarding the reform of China′s disease prevention and control system was searched by using the keywords including disease prevention and control, center for disease prevention and control (CDC), disease control, reform, and system from 2003 to 2020 in China CNKI, Wanfang Data knowledge service platform, VIP information and China biomedical literature database. The language is limited to Chinese. A total of 25 studies were included to analyze the information about the organizational structure, functional orientation, financing mechanism and personnel system of China′s disease prevention and control system.Results:The 25 studies described the specific changes and reform suggestions of China′s disease prevention and control system, including key policies (7 studies), organizational structure transformation (4 studies), institutional function transformation (7 studies), financing mechanism transformation (5 studies), personnel system reform (2 studies), and performance-based salary system reform (4 studies). Meanwhile, the reform suggestions were concluded at the top-level design system reform (two aspects), organization structure (three aspects), functioning (four aspects), and personnel guarantee mechanism (three aspects).Conclusions:This study indicates that there is a lack of empirical evidence regarding specific reform effects and content analysis at the micro level of disease prevention and control system in China. Future study should strengthen the rigorousness of study design and focus on the quantitative impacts of reform implementation in China.

Objective:To systematically understand the reform progress of disease prevention and control system in China.Methods:The literature regarding the reform of China′s disease prevention and control system was searched by using the keywords including disease prevention and control, center for disease prevention and control (CDC), disease control, reform, and system from 2003 to 2020 in China CNKI, Wanfang Data knowledge service platform, VIP information and China biomedical literature database. The language is limited to Chinese. A total of 25 studies were included to analyze the information about the organizational structure, functional orientation, financing mechanism and personnel system of China′s disease prevention and control system.Results:The 25 studies described the specific changes and reform suggestions of China′s disease prevention and control system, including key policies (7 studies), organizational structure transformation (4 studies), institutional function transformation (7 studies), financing mechanism transformation (5 studies), personnel system reform (2 studies), and performance-based salary system reform (4 studies). Meanwhile, the reform suggestions were concluded at the top-level design system reform (two aspects), organization structure (three aspects), functioning (four aspects), and personnel guarantee mechanism (three aspects).Conclusions:This study indicates that there is a lack of empirical evidence regarding specific reform effects and content analysis at the micro level of disease prevention and control system in China. Future study should strengthen the rigorousness of study design and focus on the quantitative impacts of reform implementation in China.

OBJECTIVETo study the characteristics of changes of LDH enzyme patterns of mice under slight hypoxia.

METHODSMice treated with artificial hypoxia, various tissues were made for the test of LDH enzymatic activity by the specific staining technique. LDH (1-5) relative percentage enzymatic activity (RPEA) were measured with CS-910 dual-wavelength thin layer chromatography scanner.

RESULTSThe RPEA of LDH isozymes of various tissues after slight hypoxia shifted to the isozymes LDH1 and LDH2, whose principal subunits are H subunits, and the RPEA of LDH1 (H4), LDH2 (H3M) increased, while RPEA of LDH5 (M4) in various tissues decreased prominently except the cardiac muscle, and that of LDH4 (HM3) decreased as well. After polyacrylamide gel electrophoresis (PAGE) of the hypoxia treated cardiac muscle specimen was made, activity subbands originated regularly in the isoyme patterns of LDH, with the regularity of LDH1 (0 subband), LDH2 (0-1 subbands), LDH3 (0-2 subbands), LDH4 (1-3 subbands), LDH5 (2-4 subbands). After adding appropriate amount of NAD+ to the hypoxia treated cardiac muscle specimen, PAGE showed the subbands of four isoymes (LDH2-LDH5) reduced or even totally disappeared in the isozyme patterns.

CONCLUSIONSThe negative feedback regulation of coenzymization and decoenzymization of LDH isozymes is one of the mouse stress responses to slight hypoxia.

Animals ; Hindlimb ; enzymology ; Hypoxia ; enzymology ; Isoenzymes ; metabolism ; L-Lactate Dehydrogenase ; classification ; metabolism ; Liver ; enzymology ; Mice ; Muscles ; enzymology ; Myocardium ; enzymology ; Random Allocation