Correlation between left atrial strain and left ventricular diastolic function in hypertensive patients. / å·¦æˆ¿åº”å˜ä¸Žé«˜è¡€åŽ‹æ‚£è€ å·¦å®¤èˆ’å¼ åŠŸèƒ½çš„ç›¸å ³æ€§.

OBJECTIVES: Early detection of asymptomatic diastolic dysfunction is essential to prevent the development of heart failure in hypertensive patients. Current studies suggest that left atrial strain contributes to the evaluation of left ventricular diastolic function, but there are fewer studies on the correlation between left atrial strain and diastolic function in hypertensive patients. In this study, we applied a two-dimensional speckle tracking technique to evaluate the changes in left atrial strain in hypertensive patients, and to investigate the relationship between left atrial strain and left ventricular diastolic function. METHODS: A total of 82 hypertensive patients who were visited the Department of Cardiology at the Third Xiangya Hospital of Central South University from July 2021 to January 2022, were enrolled for this study, and 59 healthy subjects served as a control group. According to the number of left ventricular diastolic function indexes recommended by the 2016 American Society of Echocardiography Diastolic Function Guidelines (mitral annular e´ velocity: Septal e´<7 cm/s, lateral e´<10 cm/s, E/e´ ratio>14, left atrial volume index>34 mL/m2, peak tricuspid regurgitation velocity>2.8 m/s), the hypertensive patients were divided into 3 groups: Group Ⅰ (0 index, n=36 ), Group Ⅱ (1 index, n=39), and Group Ⅲ (2 indexes, n=7). Two-dimensional speckle tracking technique was used to measure left atrial reservoir strain (LASr), conduit strain, and contraction strain, and to analyze the correlation between left atrial strain and left ventricular diastolic function in hypertensive patients. RESULTS: The LASr, left atrial conduit strain (LAScd), and LASr/(E/septal e´) of the hypertension group were lower than those of the control group, and E/LASr was higher than that of the control group. There was no significant difference in left atrium volume index between the 2 groups (P>0.05). Compared with Group Ⅰ, LASr, LAScd, and LASr/(E/septal e´) were decreased in Group Ⅱ and Group Ⅲ, LASr/(E/septal e´) was also decreased in Group Ⅲ compared with Group Ⅱ (all P<0.05). Compared with Group Ⅰ, E/LASr was increased in Group Ⅲ. LASr was positively correlated with septal e´, lateral e´, E, and E/A, and negatively correlated with E/septal e´. CONCLUSIONS: The changes of left atrial function in patients with early hypertension are earlier than those of left atrial structure. Left atrial strain and its combination with conventional ultrasonographic indices [LASr/(E/septal e´)] of diastolic function are potentially useful in assessing left ventricular diastolic function in hypertensive patients.

Fraxetin inhibits interleukin-1ß-induced apoptosis, inflammation, and matrix degradation in chondrocytes and protects rat cartilage in vivo.

Osteoarthritis (OA) is a disease characterized by degeneration of the joint complex due to cartilage destruction. Fraxetin, a widely used and studied coumarin compound extracted from a traditional Chinese herb (Qin Pi), has shown anti-inflammatory and antioxidant properties, but its effects on OA have not been studied. In the present study, western blotting, immunofluorescence, and terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) were used to evaluate the effects of fraxetin on IL-1ß-induced apoptotic activity, inflammatory responses, and catabolism in rat chondrocytes. The results showed that fraxetin prevented IL-1ß-induced apoptosis of chondrocytes and inhibited inflammatory mediator release by regulating the Toll-like receptor 4 (TLR4)/myeloid differentiation primary response 88 (MyD88)/nuclear factor (NF)-κB pathway in chondrocytes. Additionally, fraxetin suppressed the upregulation of matrix metalloproteinase 13 (MMP13) and degradation of collagen II in the extracellular matrix (ECM). Moreover, the effects of fraxetin in vivo were assessed in a monosodium iodoacetate (MIA)-induced rat model of OA using hematoxylin and eosin (H&E) and Safranin O-fast green staining and magnetic resonance imaging (MRI). The results showed that fraxetin protected the cartilage against destruction. In conclusion, fraxetin could be a potential therapeutic for OA.

Establishment of stable multiple myeloma cell line with overexpressed PDCD5 and its proapoptosis mechanism.

OBJECTIVE: The transfected multiple myeloma cell line showing a stable doxycycline (DOX)-induced expression of PDCD5 was established. PDCD5 overexpression in the transfected cell line was analyzed for its effect on the dexamethasone (DXM)-induced apoptosis along with a discussion on the mechanism. METHODS: (1) Lentiviral plasmid was used for the transfection of PDCD5 gene into the multiple myeloma cells. The screening was done by applying puromycin, and PDCD5 expression was induced by DOX. Real-time fluorescence quantitative PCR and Western Blot were performed to detect the expression levels of the target gene in the stable transfection group and the empty vector group; (2) The cell apoptosis rates of stable transfection group, blank group and empty vector group were measured by Annexin-APC/PI double staining flow cytometry; (3) Real-time fluorescence quantitative PCR and Western Blot were carried out to detect the expression levels of survivin, casepase-3 and Bcl-2 genes and proteins. RESULTS: PDCD5 expression was significantly increased in the stably tranfected multiple myeloma cells compared with blank group and empty vector group. The cells in the transfection group were more sensitive to DXM, and the proportion of apoptotic cells was obviously higher than that of the blank group and the empty vector group (P<0.05). Survivin and Bcl-2 were considerably downregulated in U266/PDCD5 cells and combined DXM group than in the single agent group. However, caspase-3 was significantly upregulated. CONCLUSION: Multiple myeloma cell line transfected with endogenous PDCD5 gene was established. The endogenous PDCD5 overexpression accelerated the cell apoptosis under DXM induction. The proapoptotic action of PDCD5 gene had the effect of activating casepase-3 and downregulating survivin and Bcl-2, which further promoted the apoptosis of multiple myeloma cells.