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Introduction: Preeclampsia is a pregnancy-specific disorder characterized by de novo development of hypertension and proteinuria over 20 weeks gestation that has been associated with the dysfunction of trophoblasts. Current evidence suggests that syncytin-1 plays an important role in the non-fusogenic biological activity of trophoblasts, except for specific fusogenic function. However, the underlying mechanism remains unclear., Methods: The expression and location of syncytin-1 in normal and the late-onset preeclampsia placentas were detected by quantitative real-time PCR, western blotting and immunofluorescence. Morphological and apoptosis analysis were processed in placentas. The ex vivo extravillous explant culture model was used to explore the effect of syncytin-1 on EVT outgrowths. Real-time quantitative PCR and immunoblotting were used to calculate syncytin-1 levels in the trophoblast cells before and after syncytin-1 knockdown or overexpression. CCK-8 assay was used to detect the cell viability. TUNEL staining and immunoblotting were processed in trophoblast cells. Transwell assays and wound healing assays were utilize to assess the invasion and migration of trophoblastic cells. Conditional knockout of syncytin-a mouse model was conducted to present the change of placentas in vivo. The ex vivo extravillous explant culture model was used to explore the effect of syncytin-1 on EVT outgrowths. Western blotting was used to identify the key proteins of PI3K/Akt pathways and invasion-related proteins in trophoblast cells., Results and Discussion: Here, reduced syncytin-1 was identified in the late-onset preeclampsia placentas. Reduced syncytin-1 may attenuates the EMT process by promoting apoptosis, inhibiting proliferation and invasion by suppressed PI3K/Akt pathway in trophoblast cells. Our findings provide novel insights into the non-fusogenic biological function of reduced syncytin-1 that may be involves in the pathogenesis of preeclampsia., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Objective: To investigate the effect and mechanism of Glucocorticoids (GCs) induced oxidative stress and apoptosis on necrosis of the femoral head in patients and rats., Methods: Eight patients with steroid-induced avascular necrosis of the femoral head (SINFH) and eight patients with developmental dysplasia of the hips (DDH) were enrolled in our study. In animal model, twenty male Sprague-Dawley rats were randomly divided into two groups (SINFH group and NS group). The SINFH model group received the methylprednisolone (MPS) injection, while control group was injected with normal saline (NS). MRI was used to confirm SINFH rat model was established successfully. Then, the rats were sacrificed 4 weeks later and femoral head samples were harvested. Histopathological staining was preformed to evaluate osteonecrosis. TUNEL staining was performed with 8-OHdG and DAPI immunofluorescence staining to evaluate oxidative injury and osteocyte apoptosis. Immunohistochemistry staining was used to detect Nox1, Nox2, and Nox4 protein expression., Results: MRI showed signs of typical osteonecrosis of femoral head in SIHFH patients. Histopathological staining showed that the rate of empty lacunae in SINFH patients was significantly higher (56.88% ± 9.72% vs 19.92% ± 4.18%, T = -11.04, P < 0.001) than that in DDH patients. The immunofluorescence staining indicated that the TUNEL-positive cell and 8-OHdG-positve cell in SINFH patients were significantly higher (49.32% ± 12.95% vs 8.00% ± 2.11%, T = -7.04, P = 0.002, 54.6% ± 23.8% vs 9.75% ± 3.31%, T = -4.17, P = 0.003) compared to the DDH patients. The immunohistochemistry staining showed that the protein expression of NOX1, NOX2 and NOX4 in SINFH patients were significantly increased (64.50% ± 7.57% vs 37.58% ± 9.23%, T = -3.88, P = 0.018, 90.84% ± 2.93% vs 49.56% ± 16.47%, T = -5.46, P = 0.001, 85.46% ± 9.3% vs 40.69% ± 6.77%, T = -8.03, P = 0.001) compared to the DDH patients. In animal model, MRI showed signs of edema of femoral head in MPS group, which represents SINFH rat model was established successfully. Histological evaluation showed the rate of empty lacunae in MPS group was significantly higher (25.85% ± 4.68% vs 9.35% ± 1.99%, T = -7.96, P < 0.001) than that in NS group. The immunofluorescence staining indicated that the TUNEL-positive cell and 8-OHdG-positve cell (in MPS group were significantly increased (31.93% ± 1.01% vs 11.73% ± 1.16%, T = -32.26, P < 0.001, 47.59% ± 1.39% vs 22.07% ± 2.45%, T = -22.18, P < 0.001) compared to the NS group. The immunohistochemistry staining showed that the expression of NOX2 in MPS group was significantly increased (76.77% ± 8.34% vs 50.32% ± 10.84%, T = -4.74, P = 0.001) compare with NS group., Conclusion: Our findings indicated that GC-induced NOXs expression may be an important source of oxidative stress, which could lead to osteocyte apoptosis in the process of SINFH., (© 2021 The Authors. Orthopaedic Surgery published by Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.)

Oxidative stress induced by long-term glucocorticoid (GC) use weakens the repair capacity of bone tissue. Nicotinamide adenine dinucleotide phosphate, reduced form (NADPH) oxidase (NOX) is a superoxide-generating enzyme that plays an important role in regulating bone metabolism. To clarify the role of nonphagocytic NOX isoforms in osteoblast reactive oxygen species (ROS) generation and apoptosis, dexamethasone was used to establish a high-dose GC environment in vitro . A dose-dependent increase in intracellular ROS generation was demonstrated, which was accompanied by increased osteoblastic MC3T3-E1 cell apoptosis. Addition of the ROS inhibitor NAC ( N -acetyl-L-cysteine) or NOX inhibitor DPI (diphenyleneiodonium) reversed this effect, indicating that NOX-derived ROS can induce osteoblast apoptosis under high-dose dexamethasone stimulation. NOX1, NOX2, and NOX4 are NOX homologs recently identified in bone tissue. To clarify the NOX isoforms that play a role in osteoblast ROS generation, Nox1 , Nox2 , and Nox4 mRNA expression and NOX2 and NOX4 protein expression were analyzed. Nox1 and Nox4 mRNA expression was elevated in a dose-dependent manner after culture in 100 nM, 250 nM, 500 nM, or 1000 nM dexamethasone, and the increased expression of NOX1 mRNA was more significant compared with NOX4 mRNA. Small interfering RNAs (siRNAs) were used to confirm the role of NOX1 and NOX4 in ROS generation. To clarify the signaling pathway in ROS-induced osteoblast apoptosis, mitogen-activated protein kinase (MAPK) signaling molecules were analyzed. Phosphorylated ASK1 and p38 levels were significantly higher in the 1000 nM dexamethasone group, which NAC or DPI markedly attenuated. However, the total mRNA and protein levels of ASK1 and p38 between the dexamethasone group and control were not significantly different. This is related to ROS regulating the posttranslational modification of ASK1 and p38 in MC3T3-E1 cell apoptosis. Altogether, NOX1- and NOX4-derived ROS plays a pivotal role in high-dose dexamethasone-induced preosteoblast apoptosis by increasing phosphorylated ASK1 and p38 and may be an important mechanism in steroid-induced avascular necrosis of the femoral head (SANFH).

The present study was conducted to investigate effects and mechanisms of action of phenolic alkaloids of Menispermum dauricum (PAMD) on gastric cancer in vivo. In vitro, cell apoptosis of human gastric cancer cell line SGC-7901 was observed using fluorescence staining. In vivo, a mice model was constructed to observe tumor growth with different doses. Cell apoptosis was examined using flow cytometry and K-RAS protein expression using Western blotting. The mRNA expression of P53, BCL-2, BAX, CASPASE-3, K-RAS was examined by real-time PCR. PAMD significantly suppressed tumor growth in the xenograft model of gastric cancer in a dose- dependent manner (p<0.01). Functionally, PAMD promoted cell apoptosis of the SGC-7901 cells and significantly increased the rate of cell apoptosis of gastric tumor cells (p<0.05). Mechanically, PAMD inhibited the expression of oncogenic K-RAS both at the mRNA and protein levels. In addition, PAMD affected the mRNA expression of the cell apoptosis-related genes (P53, BCL-2, BAX, CASPASE-3). PAMD could suppress gastric tumor growth in vivo, possibly through inhibiting oncogenic K-RAS, and induce cell apoptosis possibly by targeting the cell apoptosis-related genes of P53, BCL-2, BAX, CASPASE-3.

Selective peroxisome proliferator-activated receptor-γ (PPAR-γ) agonist affects the functions of endothelial progenitor cells (EPCs). This study explores the effect of selective PPAR-γ agonist, pioglitazone, on EPC apoptosis. The cells were cultured and identified via the double staining method in a medium containing different concentrations of pioglitazone. EPC apoptosis was detected by flow cytometry. On Day 7, EPCs engulfed DiL-ac-LDL and FITC-UEA-1, and showed yellow fluorescence in a laser-scanning confocal microscope. EPC apoptosis inhibition was maximal at 50 µmol/L. The ability of pioglitazone to prevent EPC apoptosis may be mediated by the PI3K/Akt signal pathway. The use of thiazolidine two ketone (TZD) to reduce EPC apoptosis may have some potential in treating vascular diseases., (© 2013 International Federation for Cell Biology.)

It has been reported that exposure to infrasound causes cardiac dysfunction. Allowing for the key role of apoptosis in the pathogenesis of cardiovascular diseases, the objective of this study was to investigate the apoptotic effects of infrasound. Cardiac myocytes cultured from neonatal rats were exposed to infrasound of 5 Hz at 130 dB. The apoptosis was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling. Also, the expression levels of a series of apoptosis-related proteins were detected. As a result, infrasound induced apoptosis of cultured rat cardiac myocytes in a time-dependant manner. The expression of proapoptotic proteins such as Bax, caspase-3, caspase-8, caspase-9, and FAS was significantly up-regulated, with concomitant down-regulated expression of antiapoptotic proteins such as Bcl-x, and the inhibitory apoptosis proteins family proteins including XIAP, cIAP-1, and cIAP-2. The expression of poly (ADP-ribose) polymerase and β-catenin, which are the substrate proteins of caspase-3, was significantly decreased. In conclusion, infrasound is an apoptotic inducer of cardiac myocytes.

Objective: To investigate the role of chloride channels in the apoptosis of poorly differentiated nasopharyngeal carcinoma CNE-2Z cells induced by gambogic acid (GA)., Methods: MTT assay was applied to detect the proliferation of CNE-2Z cells after GA treatment, and the cell apoptosis was detected by Hoechst 33342 staining. Whole-cell patch clamp technique was employed to record GA-activated Cl(-) currents in the cells., Results: GA inhibited the cell proliferation in a time- and concentration-dependent manner with an IC(50) of 3.1 µmol/L for a 48-h treatment. The apoptosis-inducing effect of 8 µmol/L GA was attenuated by the chloride channel blocker NPPB (100 µmol/L) and tamoxifen (20 µmol/L). GA induced an outward-rectified Cl(-) current in the cells, which was significantly inhibited by NPPB., Conclusion: GA suppresses cell proliferation and induces apoptosis by activating Cl(-) channels in CNE-2Z cells, suggesting the important role of Cl(-) channels in GA-induced apoptosis.

Four new (1-4) and 13 known (5-17) sesquiterpene lactones along with two known diterpenes (18, 19) were isolated from the whole plant of Carpesium faberi. The new structures were elucidated by means of spectroscopic techniques and some chemical transformations to be pseudoguaian-1α(H)-8α,12-olide-4β-O-β-d-glucopyranoside (1), 4β,10α-dihydroxy-5α(H)-1,11(13)-guaidien-8α,12-olide (2), 4β,10β-dihydroxy-5α(H)-1, 11(13)-guaidien-8β,12-olide (3), and (4S)-acetyloxyl-11(13)-carabren-8β,12-olide (4). All isolates were tested against MCF-7 human breast cancer cells using the MTT assay. Among them, the sesquiterpene lactones (except tomentosin 17) possessing an α-methylene-γ-lactone moiety were found to have in vitro antiproliferative activities, with IC(50) values of 3.0-38.8μg/mL. The effects of four selected sesquiterpene lactones (guaianolide 2, carabranolide 4, pseudoguaianolide 9, eudesmanolide 13) on the cell cycle were examined using flow cytometry (FCM)., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Objective: To study the effect of multiglycosides of Tripterygium wilfordii (GTW) on sperm apoptosis in male rats and its possible mechanisms., Methods: Sixteen male SD rats were equally assigned to two groups to receive GTW and carboxymethylcellulose (CMC) intragastrically, both at 20 mg/(kg x d) for 6 weeks. Then the epididymal sperm was collected for the measurement of the apoptosis rate, sperm membrane lipid fluidity and the contents of NO, MDA and SOD by flow cytometry and spectrophotometric determination., Results: After 6 weeks of medication, the GTW group showed a significant increase in sperm apoptosis and contents of NO and MDA (P < 0.01) and a remarkable decrease in sperm membrane lipid fluidity (P < 0.05) and SOD content (P < 0.01) as compared with the CMC control group., Conclusion: GTW can damage sperm membrane lipid peroxidation and sperm membrane structure, increase sperm apoptosis, and reduce sperm membrane lipid fluidity.

Aim: To explore the mechanisms of hypoxic preconditioning on protecting cultured astrocytes from hypoxia injury., Methods: Cultured astrocytes were divided randomly into several groups: control(C), hypoxia(H) and hypoxic preconditioning (HP). Cells MTT metabolic activity, qualitation of apoptosis and modality to explore the protection effects of hypoxic preconditioning. Immunocytochemistry of Bcl-2 and Bax to explore the mechanisms of hypoxic preconditioning on protecting astrocytes from hypoxia., Results: Compared with H group there was marked increase of MTT metabolic activity in HP48 and HP72 groups. Immunocytochemistry of Bcl-2 and Bax showed that compared with H group, expression of Bcl-2 was increased in HP group, while expression of Bax was decreased in HP group., Conclusion: Hypoxic preconditioning can protect astrocytes from hypoxia. One possible mechanism maybe concerned with inhibition of Bax and maintain of Bcl-2 to depress apoptosis procedure.

Objective: Sympathetic overactivity is closely connected with cell injury and contractile dysfunction during myocardial ischemia/reperfusion (MI/R). Insulin exerts protection for the I/R heart and the underlying mechanisms remain unclear. This study aimed to investigate the ability of insulin to modulate beta-adrenergic actions on myocardial contraction and post-ischemic injury in acute MI/R and the underlying mechanism., Methods: Isolated hearts from adult SD rats were subjected to MI/R (30 min/2 h) and treated with isoproterenol (ISO) or/and insulin. Myocardial contraction, cardiomyocyte apoptosis, myocardial injury and infarction were assessed. In a separate study, isolated ventricular myocytes were subjected to simulated I/R (15/30 min) and myocyte shortening and intracellular Ca2+ transient in response to ISO during reperfusion were assessed with presence or absence of insulin., Results: In isolated I/R hearts, insulin largely reversed the ISO-associated contractile functional impairment at 2 h after MI/R, inhibiting ISO-induced declines in heart rate and left ventricular systolic pressure by 34.0% and 23.0% and preventing ISO-induced elevation in left ventricular end-diastolic pressure by 28.7% respectively (all P < 0.05). In addition, ISO alone resulted in enlarged infarct size, elevated CK and LDH activity and increased apoptotic index in I/R hearts compared with vehicle, which were inhibited by treatment of insulin (all P < 0.05). Interestingly, in SI/R cardiomyocytes, insulin alone at 10(-7 )mol/l increased cell contraction whereas attenuated the positive inotropic response to ISO (10(-9 )mol/l) during R as evidenced by a 18.7% reduction in peak twitch amplitude and a 23.9% reduction in calcium transient amplitude (both P < 0.05). Moreover, insulin blunted ISO-mediated increase in PKA activity, enhanced the PKA-dependent phosphorylation of phospholamban (PLB), resulting in increased sarcoplasmic reticulum Ca2+-ATPase (SERCA2a) activity., Conclusion: Insulin attenuated the contractile response to beta-AR stimulation and suppressed ISO-elicited cardiac dysfunction and cell injury in MI/R. The inhibitory effect of insulin on the beta-adrenergic action involved the inhibition of PKA-mediated Ca2+ transient and promotion of post-ischemic Ca2+ handling.

Objective: Physical activity has been shown to improve cardiovascular function and to be beneficial to type 2 diabetic patients. However, the effects of aerobic exercise (AE) on myocardial ischemia/reperfusion (MI/R) are largely unclear. Therefore, the aims of the present study were to determine whether long-term AE can protect the heart against I/R injury, and if so, to investigate the underlying mechanism., Methods: Adult male Sprague-Dawley rats were randomly subjected to 8 weeks of either sedentary or free-loading swimming exercise (3 h/day, 5 d/week). Then the animals were subjected to 30 min MI followed by 4 h R. Arterial blood pressure and left ventricular pressure (LVP) were monitored throughout the whole MI/R procedure. Plasma creatine kinase (CK) and lactate dehydrogenase (LDH) activities were measured spectrophotometrically. Myocardial infarction and myocardial apoptosis (TUNEL analysis) were determined in a blinded manner., Results: MI/R caused significant cardiac dysfunction and myocardial apoptosis (strong TUNEL-positive staining). Compared with sedentary group, rats subjected to 8 weeks of AE showed protection against MI/R as evidenced by reduced myocardial infarction (26.8 +/- 1.5% vs. 35.3 +/- 2.4%, n = 8, P < 0.05), inhibited cardiomyocyte apoptosis (decreased apoptotic index (12.4 +/- 1.1% vs. 21.0 +/- 1.7%, n = 8, P < 0.01) and decreased myocardial caspase-3 activity), decreased plasma CK and LDH activities and improved recovery of cardiac systolic/diastolic function (including LVSP and +/-LVdP/dt) at the end of R. Moreover, exercise resulted in 1.7-fold, 2.5-fold and 2.5-fold increases in Akt expression, Akt phosphorylation and glycogen synthase kinase-3beta phosphorylation in I/R myocardium, respectively (n = 3, all P < 0.05). More importantly, treatment with wortmannin, a PI3 kinase inhibitor, 15 min before R not only significantly blocked Akt phosphorylation (P < 0.05) in exercise rats, but also abolished long-term AE-induced cardioprotection for the I/R heart as manifested by increased apoptosis and myocardial infarction, and reduced cardiac function., Conclusion: Long-term AE exerts cardioprotective effect against MI/R injury, including anti-cardiomyocyte apoptosis, which is at least partly via PI3 kinase-dependent and Akt-mediated mechanism.

Objective: To observe the effect of recombinant adenovirus Ad-ING4 on K562 cells., Methods: Human ING4 recombinant transfer vector pAdTrack-CMV-ING4 was constructed by enzyme digest and ligation of human ING4 gene which was obtained through site specific point mutation of mouse ING4. The vector was co-transduced into BJ5183 E. coli with pAdEasy-1. The new recombinant adenovirus vector pAdEasy-1-pAdTrack-CMV-hING4 was transfected into QBI-293A cells. To obtain the ING4 recombined adenovirus (Ad-ING4). Ad-ING4 was used to infect K562 cells. The effect on K562 cells of ING4 was tested by LSCM FCM and immunohistochemistry., Results: Human ING4 recombinant adenovirus vector was constructed successfully, and high titre ING4 recombinant adenovirus (Ad-ING4) was obtained. ING4 can down-regulate the expression of bcl-2 and up-regulate expression of bax. The apoptosis of K562 cells induced by ING4 was proved by LSCM FCM and immunohistochemistry. The apoptosis rate was 19.7% (after 72h), which displayed significant difference compared with that of control groups (P < 0.01)., Conclusion: Ad-ING4 can inhibit the growth of K562 cells and induce the cells apoptosis. The human ING4 recombinant adenoviral vector constructed might provide an approach to the target therapy of tumors.

Aim: To investigate the role of intercellular potassium in tachyplesin-induced HL-60 cells apoptosis., Methods: The concentration of intercellular potassium, cell volume and mitochondrial membrane potential were examined by flow cytometry., Results: The concentration of intercellular potassium reduced in a time-dependent manner in tachyplesin-treated HL-60 cells. In addition, the loss of mitochondrial membrane potential was tightly coupled with the shrinkage of cell volume. Different caspase inhibitors protected against DNA degradation but did not prevent the loss of HL-60 cell viability induced by tachyplesin. Ba2+, which was a kind of blocker of volume-regulatory K+ channels, increased the viability of tachyplesin-treated HL-60 cells and maintained mitochondrial membrane potential and cell volume., Conclusion: Efflux of K+ was an important reason for apoptosis in tachyplesin-treated HL-60 cells. Efflux of K+ affected the viability of tachyplesin-treated HL-60 cells independent of the process of caspase activation.

Objectives: Our previous study has shown that slow or "controlled" reperfusion for the ischemic heart reduces cardiomyocyte injury and myocardial infarction, while the mechanisms involved are largely unclear. In this study, we tested the hypothesis that enhancement of survival and prevention of apoptosis in hypoxic/reoxygenated cardiomyocytes by hypoxic postconditioning (HPC) are associated with the reduction in peroxynitrite (ONOO(-)) formation induced by hypoxia/reoxygenation (H/R)., Methods: Isolated adult rat cardiomyocytes were exposed to 2 h of hypoxia followed by 3 h of reoxygenation. After 2 h of hypoxia the cardiomyocytes were either abruptly reperfused with pre-oxygenized culture medium or postconditioned by two cycles of 5 min of brief reoxygenation and 5 min of re-hypoxia followed by 160 min of abrupt reoxygenation., Results: H/R resulted in severe injury in cardiomyocytes as evidenced by decreased cell viability, increased LDH leakage in the culture medium, increased apoptotic index (P values all less than 0.01 vs. normoxia control group) and DNA ladder formation, which could be significantly attenuated by HPC treatment applied before the abrupt reoxygenation (P < 0.05 vs. H/R group). In addition, H/R induced a significant increase in ONOO(-) formation as determined by nitrotyrosine content in cardiomyocytes (P < 0.01 vs. normoxia control). Treatment with the potent ONOO(-) scavenger uric acid (UA) at reoxygenation significantly decreased ONOO(-) production and protected myocytes against H/R injury, whereas the same treatment with UA could not further enhance myocyte survival in HPC group (P > 0.05 vs. HPC alone). Statistical analysis showed that cell viability closely correlated inversely with myocyte ONOO(-) formation (P < 0.01)., Conclusion: These data demonstrate that hypoxic postconditioning protects myocytes against apoptosis following reoxygenation and enhances myocytes survival, which is partly attributable to the reduced ONOO(-) formation following reoxygenation.

Objective: Survivin is a member of the inhibitors of apoptosis protein (IAP) family. Recent researches had shown that survivin plays an important role in oncogenesis. This study was designed to investigate the expression of survivin in transitional cell carcinoma (TCC) of urinary bladder and its clinical significance., Methods: Immunohistochemical assay was used to detect the expression of survivin in 75 cases of tumor tissue and 7 cases of normal bladder tissue., Results: The expression rates of survivin were 77.3% (58/75) in TCC of urinary bladder, whereas no expression of survivin was detected in the 7 cases of normal bladder tissue., Conclusions: Expression of survivin protein was observed in the tumor tissue derived from the patients with bladder TCC, indicating that this protein may play an important rule in carcinogenesis of human urinary bladder. The expression of survivin was statistically significant associated with tumor grade. Our results suggested that the expression of survivin may be considered as a prognostic factor for bladder TCC.

Objective: To study the effects of glucose-insulin-potassium (GIK) cocktail on cardiac myocyte apoptosis and cardiac functional recovery following myocardial ischemia/reperfusion (MI/R), and to further determine the role of insulin in the GIK-induced cardioprotective effect in vivo ., Methods: Forty eight male rabbits were subjected to 40 min MI followed by R for 3 h and were randomly received one of the following treatments: saline, GIK (glucose: 150 g/L, insulin: 60 U/L and KCl: 80 mmol/L), or insulin (n = 16 in each group) at 1 ml x kg(-1) x h(-1), beginning 30 min before MI and continuing throughout the 3 h-reperfusion. Blood glucose, electrolytes, arterial blood pressure and left ventricular pressure (LVP) were monitored throughout the experiment. Plasma creatine kinase (CK) and lactate dehydrogenase (LDH) activity were measured spectrophotometrically. Myocardial infarction and myocardial apoptosis (both DNA laddering and TUNEL analysis) were determined in a blinded manner., Results: MI/R caused significant cardiac dysfunction and myocardial apoptosis (both strong DNA ladder formation and TUNEL-positive staining). Compared with vehicle, GIK-treated rabbits showed protection against MI/R as evidenced by reduced myocardial infarction (19.7% +/- 2.6% vs . 26.8% +/- 3.3% of vehicle, n = 10, P < 0.05), marked decrease in DNA fragmentation and apoptotic index (11.0% +/- 2.1% vs . 20.1% +/- 3.1% of vehicle, n = 6, P < 0.01), significant decrease of plasma CK and LDH and improved recovery of cardiac systolic/diastolic function at the end of R. Treatment with insulin alone decreased blood glucose significantly but still exerted cardioprotective effects comparable with that of GIK., Conclusions: GIK exerts cardioprotective effects against postischemic myocardial injury and improves cardiac functional recovery in vivo . Insulin, mainly through the anti-apoptotic effect, plays a key role in the GIK-elicited myocardial protection in MI/R.

The inhibition effects of Sargassum fusiforme Polysaccharides (SFPS) on proliferation of human HL-60 promyeloid leukemia cells were measured by MTT assay. SFPS-induced apoptosis in HL-60 cells was observed by electron microscopy, flow cytometry and DNA electrophoresis. The results revealed that SFPS exhibited antiproliferative activity which depended on dosage and time. After incubation for 24, 36, 48 and 72 h, SFPS had growth inhibitory effect on HL-60 cells with IC50 of 390, 362, 402 and 421 mg/L. A ladder-like pattern of DNA fragmentation was demonstrated on agarose gel electrophoresis after HL-60 cells induced by SFPS at a dose of 300 mg/L and 500 mg/L. Morphological examination by electron microscopy showed cells with few microvilli on the surface, chromatin condensation and margination, cell shrinkage and the presence of "apoptosis bodies". The DNA content analysis of FCM showed pre-G1 cells and increased G2 period ratio, in addition, it demonstrated that apoptosis induced by SFPS was dose-and time-dependent. In conclusion, the antitumor effect of SFPS is relative to cell apoptosis and the blocking of G2/M period cells.

Objective: To investigate the signaling pathway involved in the insulin-elicited anti-apoptotic effect during myocardial ischemia and reperfusion (MI/R) in vivo., Methods: Male Sprague-Dawley rats were anesthetized and subjected to 30 min of myocardial ischemia followed by 4h-reperfusion. Rats were randomly treated with intravenous infusion of saline (vehicle, 4 ml.kg(-1).h(-1)), insulin (60 U/L), or insulin + wortmannin 5 min before reperfusion and continuing throughout the 4h-reperfusion period. Cardiac myocyte apoptosis was determined both qualitatively and quantitatively by DNA laddering and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) methods. Myocardial nitric oxide (NO) was measured by using NO-specific chemiluminescence detector. Activations of Akt and p38 mitogen-activated protein kinase (MAPK) were determined by kinase activity assays using corresponding kinase activity assay kits (Cell Signaling)., Results: In the vehicle-treated rats, MI/R caused significant cardiac myocyte apoptotic death. Treatment with insulin produced a significant anti-apoptotic effect as evidenced by a marked reduction of apoptotic index [(8.0 +/- 2.9)% vs. (19.3 +/- 4.6)% of vehicle, P < 0.01] and decreased formation of myocardial DNA fragmentation. In addition, insulin treatment produced 2.7-fold increase (P < 0.01) of myocardial Akt activity and 28% increase of myocardial NO production (P < 0.05), while p38 MAPK activity changed insignificantly as compared with that of vehicle (P > 0.05). Both insulin-induced Akt activation and anti-apoptotic effect could be abrogated by wortmannin, a phosphatidylinositol (PI) 3-kinase inhibitor., Conclusion: In vivo treatment with insulin at the initial of reperfusion significantly reduced postischemic apoptotic death via the PI3-kinase-Akt signaling pathway. Akt, but not p38 MAPK, activation plays a key role in the insulin-induced anti-apoptotic effect in MI/R.

Background & Objective: Chinese herb Albizzia Lucidior I. Nielsen (ALN) belongs to Albizzia of Legume. It was reported that the chemical constituents from the bark of Albizza plants possess antitumor activity. So far there was no report about the components of Albizzia Lucidior I. Nielsen and its bioactivities. This study was designed to investigate the apoptosis-inducing activity of ALN extract on human tumor cells and the related mechanism., Methods: The effect of ALN extract on tumor cells proliferation, cell cycle distribution, and apoptosis inducing were determined by cell molecular biological methods including MTT assay, nucleus morphological characteristics observation, cell size examination, agarose gel electrophoresis, and flow cytometry. Living cells reaction to ALN extract was also detected by cytosensor microphysiometry. Apoptosis related proteins, poly(ADP-ribose) polymersase (PARP), bcl-2 and Bax protein levels were measured by Western blot., Results: ALN extract showed proliferation inhibition on human tumor cells by inducing apoptosis. The IC50 value to K562 cell line was (29.04 +/- 12.67) micrograms/ml. Western blot analysis showed that PARP was proteolysized and Bax protein level was enhanced, whereas bcl-2 protein level was unchanged., Conclusions: ALN extract induce human tumor cells apoptosis, probably by increasing Bax protein expression.