Glycyrrhizin arginine salt protects against cisplation-induced acute liver injury by repressing BECN1-mediated ferroptosis.

The study aimed to investigate the protective effects and biological mechanisms of glycyrrhizin arginine salt (Gly-Arg) against cisplatin (Cis)-induced liver injury. Our data showed that Gly-Arg improved Cis-induced liver injury. Further study showed that BECN1 (beclin1) and LC3-II/LC3-I protein expression was significantly increased in primary hepatocytes and mouse liver tissues after Cis treatment, but Gly-Arg reduced the protein levels of BECN1 and LC3-II/LC3-I in primary hepatocytes and mouse liver tissues. Also, Gly-Arg improved indicators related to Cis-induced ferroptosis. Furthermore, Cis increased colocalization of lysosomal membrane-associated protein 1A (LAMP1) with ferritin heavy chain 1 (FTH1) in primary mouse hepatocytes, while Gly-Arg intervention attenuated this colocalization in primary hepatocytes. More improtantly, Cis enhanced the formation of the BECN1-xCT complex, thus inhibiting solute carrier family 7 member 11 (SLC7A11, xCT) and glutathione peroxidase-4 (GPX4) activity. In contrast, Gly-Arg intervention disrupted the formation of this complex. However, Gly-Arg alleviated Cis-induced liver injury in mice by preventing autophagic death and ferroptosis through the inhibition of BECN1-xCT complex formation.

Tetrandrine Citrate Suppresses Breast Cancer via Depletion of Glutathione Peroxidase 4 and Activation of Nuclear Receptor Coactivator 4-Mediated Ferritinophagy.

Tetrandrine citrate (TetC), a novel tetrandrine salt with high water solubility, demonstrates a potent antitumor activity in chronic myeloid leukemia. Studies have indicated an important role of ferroptosis in breast cancer (BC). However, whether TetC inhibits BC progression via ferroptosis has never been explored. In the present study, we showed that TetC had a significant inhibitory effect on the proliferation and migration of MCF7 and MDA-MB-231 cells. Then, we combined TetC with different inhibitors to determine which form of cell death could be driven by TetC. MTT assay showed that ferrostatin (Fer-1) demonstrated the most potent effect on improving TetC-induced cell death in contrast to other inhibitors. TetC was also shown to significantly increase the mRNA level of prostaglandin-endoperoxide synthase 2 (Ptgs2), a ferroptosis marker. Further studies showed that TetC significantly suppressed the expression of glutathione peroxidase 4 (GPX4) and ferritin heavy chain 1 (FTH1) but increased the expression of nuclear receptor coactivator 4 (NCOA4) in MCF7 and MDA-MB-231 cells even in the presence of erastin or Ras-selective lethal 3 (RSL3). Collectively, we showed novel data that ferroptosis was a major form of TetC-induced cell death. Moreover, TetC-induced ferroptotic cell death was achieved via suppressing GPX4 expression and activating NCOA4-mediated ferritinophagy in BC cells.

Antitumor activity of tetrandrine citrate in human glioma U87 cells in vitro and in vivo.

Since the current methods of treatment for malignant glioma, radiotherapy and chemotherapy, are unsatisfactory, the development of novel therapeutic compounds is required. In the present study, the inhibitory effect of tetrandrine citrate (TetC) on the proliferation of human glioma U87 cells, as well as its mechanism of action, were investigated. An MTT assay was used to assess cell viability in vitro, and the production of intracellular reactive oxygen species (ROS) was determined by assessing the fluorescence intensity of 2,7­-dichlorofluorescein (DCF). Flow cytometry was used to determine the level of apoptosis and cell cycle status, and the protein expression levels of apoptosis­associated proteins were determined using western blotting. Additionally, the antitumor activity of TetC was assessed in vivo using a nude mouse xenograft model. The results revealed that in vitro, the proliferative rate of U87, U251 and human umbilical vein endothelial cells (HUVECs) was significantly reduced in a dose­dependent manner following treatment with TetC, although TetC had the greatest inhibitory effect on U87 cells. The vacuolization and apoptosis of U87 cells was induced using 10 and 20 µmol/l TetC, respectively. The overall proliferative inhibition was associated with an increase in the levels of ROS and apoptosis. In TetC­treated cells, the expression levels of apoptosis­related proteins, including cleaved (CL) caspase­3, Fas, phosphorylated (p)­p38 and p­JNK, were increased, whereas those of caspase­3 and Bcl­2 were decreased. In vivo, TetC was highly effective at inhibiting the growth of human glioma U87 xenografts in BALB/c nude mice, with a percentage growth inhibition of ≥68.7%. These findings indicated that the potent antitumor activity of TetC may be mediated through an increase in ROS levels, the downregulation of Bcl­2, and the upregulation of CL caspase­3, Fas, p­p38 and p­JNK expression levels.

Dynamic influence of Rhein lysinate on HeLa cells.

In a previous study, it was demonstrated that Rhein lysinate (RHL) inhibited HeLa cell proliferation via a specific mechanism. The aim of the present study was to clarify the mechanism of RHL by investigating its effect on mitochondrial damage and cell apoptosis. The results indicated that RHL inhibited cell growth and proliferation in HeLa cells. HeLa cells treated with RHL developed extensive vacuolization in a dose- and time-dependent manner. Ultrastructure analysis using transmission electron microscopy revealed that the vacuoles observed were damaged mitochondria and endoplasmic reticulum. The effects of RHL on mitochondria were further confirmed by a decrease in mitochondrial membrane potential and increased generation of reactive oxygen species. The mitochondrial proteome was analyzed, and the results demonstrated that the expression of the cytoskeletal protein keratin and dermal papilla derived protein 12 (associated with the oxidation-reduction process), which are associated with mitochondrial structure and function, were decreased compared with the untreated control group. Hoechst staining, flow cytometry and western blotting also revealed that apoptosis was induced at 24 h following RHL treatment. These results confirm that RHL toxicity in HeLa cells is a dynamic process. Vacuolar degeneration appeared in HeLa cells treated with 160 µmol/l RHL during the first 6 h and with the extension of RHL treatment, cell apoptosis was presented at ~24 h in HeLa cells.

Therapeutic Effect of Glycyrrhizin Arginine Salt on Rat Cholestatic Cirrhosis and its Mechanism.

To investigate the therapeutic effect of glycyrrhizin arginine salt on rat cholestatic cirrhosis, we subjected male Sprague Dawley rats to common bile duct ligation for 14 days and treated them with distilled water (model group), arginine, or a low or high dose of glycyrrhizin arginine salt by gavage. A sham-operated group was used as a control group. Treatment with glycyrrhizin arginine salt substantially improved animal growth rates, reduced the ratio of liver weight to body weight and decreased total bilirubin, aspartate aminotransferase, 8-isoprostane and malondialdehyde compared with the values measured in the model group. The progress of liver fibrosis, as detected by hematoxylin and eosin and Masson's trichrome staining, was slower in the glycyrrhizin arginine salt groups than in the model group or the arginine group. Reductions of bile salt pool size, hepatic hydroxyproline content and fibrosis score were also seen in the glycyrrhizin arginine salt groups compared with the model group. Furthermore, glycyrrhizin arginine salt significantly reduced the expression of transforming growth factor [Formula: see text]1 (TGF-[Formula: see text]1), [Formula: see text]-smooth muscle actin, tumor necrosis factor-[Formula: see text] and matrix metalloproteinases 2 and 9. Glycyrrhizin arginine salt also inhibited the expression of [Formula: see text]-SMA and matrix metalloproteinases 2 and 9 in response to TGF-[Formula: see text]1 in LX-2 cells and primary rat hepatic stellate cells and mitigated the cytotoxicity induced by rat bile in HepG2 cells and primary rat hepatocytes.

Rhein lysinate protects renal function in diabetic nephropathy of KK/HlJ mice.

The purpose of the present study was to assess the protective effects of rhein lysinate (RHL) in a KK/HlJ mouse model of diabetic nephropathy (DN) and to explore its mechanism of action. A total of 4 groups were established: C57BL/J control, the KK/HlJ model and 25 and 50 mg/kg/day RHL-treated KK/HlJ groups. The KK/HlJ mouse model of DN was established by streptozotocin injection, followed by maintenance on a specific diet. The albumin-to-creatinine ratio (ACR) was determined at 5 weeks and at 16 weeks, the kidneys were harvested, and morphological examination and immunohistochemical analysis were performed. The levels of malondialdehyde (MDA), as well as superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) activities in the kidneys were measured using appropriate assay kits. The expression of inflammatory factors and associated proteins was analyzed using western blot analysis. At 5 weeks, the levels of ACR in KK/HlJ mice were increased, which was inhibited by treatment with RHL. Treatment with RHL (50 mg/kg/day) decreased the body weight of KK/HlJ mice. Compared with the C57BL/J control, the KK/HlJ model mice had a significantly lower activity of SOD and GSH-px in the kidneys, but had significantly higher levels of MDA. Treatment of KK/HlJ mice with RHL significantly increased the activities SOD and GSH-px, and reduced the MAD level in the kidneys. Renal tubular epithelial cell edema was observed in KK/HlJ mice but not in C57BL/J mice. RHL decreased the incidence of renal tubular epithelial cell edema and significantly decreased the expression of TNF-α and IL-6 as well as the expression and phosphorylation of NF-κB in the kidneys. Therefore, DN is associated with the expression of inflammatory factors, renal tubular epithelial cell edema and renal dysfunction in KK/HlJ mice. RHL improves renal function by decreasing kidney inflammation.

The anti-hepatic fibrosis effects of dihydrotanshinone I are mediated by disrupting the yes-associated protein and transcriptional enhancer factor D2 complex and stimulating autophagy.

BACKGROUND AND PURPOSE: Dihydrotanshinone I (DHI), a lipophilic component of traditional Chinese medicine Salvia miltiorrhiza Bunge, has various therapeutic effects. We investigated the anti-fibrotic effect of DHI and its underlying mechanisms in vitro and in vivo. EXPERIMENTAL APPROACH: Rats subjected to bile duct ligation (BDL) were treated with DHI (25 mg·kg-1 ·day-1 , i.p.) for 14 days. Serum biochemical and liver tissue morphological analyses were performed. The human hepatic stellate cell line LX-2 served as a liver fibrosis model in vitro. Liver fibrogenic genes, yes-associated protein (YAP) downstream genes and autophagy markers were examined using western blot and real-time PCR analyses. Similar analyses were done in rat primary hepatic stellate cells (pHSCs). Autophagy flux was assessed by immunofluorescence. KEY RESULTS: In BDL rats, DHI administration attenuated liver necrosis, bile duct proliferation and collagen accumulation and reduced the expression of genes associated with fibrogenesis, including Tgfb1, Mmp-2, Acta2 and Col1a1. DHI (1, 5, 10 µmol·L-1 ) time- and dose-dependently suppressed the protein level of COL1A1, TGFß1 and α-SMA in LX-2 cells and rat pHSCs. Furthermore, DHI blocked the nuclear translocation of YAP, which inhibited the YAP/TEAD2 interaction and its downstream fibrogenic genes, connective tissue growth factor, SOX4 and survivin. This stimulated autophagic flux and accelerated the degradation of liver collagen. CONCLUSIONS AND IMPLICATIONS: DHI exerts anti-fibrotic effects in BDL rats, LX-2 cells and rat pHSCs by inhibiting the YAP and TEAD2 complex and stimulating autophagy. These findings indicate that DHI may be a potential therapeutic for the treatment of liver fibrosis.

Recombinant adenovirus of human p66Shc inhibits MCF-7 cell proliferation.

The aim of this work was to construct a human recombinant p66Shc adenovirus and to investigate the inhibition of recombinant p66Shc adenovirus on MCF-7 cells. The recombinant adenovirus expression vector was constructed using the Adeno-X Adenoviral System 3. Inhibition of MCF-7 cell proliferation was determined by MTT. Intracellular ROS was measured by DCFH-DA fluorescent probes, and 8-OHdG was detected by ELISA. Cell apoptosis and the cell cycle were assayed by flow cytometry. Western blot were used to observe protein expression. p66Shc expression was upregulated in 4 cell lines after infection. The inhibitory effect of p66Shc recombinant adenovirus on MCF-7 cells was accompanied by enhanced ROS and 8-OHdG. However, no significant differences were observed in the cell apoptosis rate. The ratio of the cell cycle G2/M phase showed a significant increase. Follow-up experiments demonstrated that the expressions of p53, p-p53, cyclin B1 and CDK1 were upregulated with the overexpression of p66Shc. The Adeno-X Adenoviral System 3 can be used to efficiently construct recombinant adenovirus containing p66Shc gene, and the Adeno-X can inhibit the proliferation of MCF-7 cells by inducing cell cycle arrest at the G2/M phase. These results suggested that p66Shc may be a key target for clinical cancer therapy.

Rhein lysinate decreases inflammation and adipose infiltration in KK/HlJ diabetic mice with non-alcoholic fatty liver disease.

The objective of this study was to investigate the protective effects of rhein lysinate (RHL) on the liver. Mice were divided into four groups: C57BL/J control, the KK/HlJ diabetic model, and 25 and 50 mg/kg/day RHL-treated KK/HlJ groups. The KK/HlJ diabetic mouse model was made by injecting STZ and feeding mice diabetic food. At 16 weeks, mice were sacrificed and their livers were harvested. The results indicated that compared with the C57BL/J control group, the body weights, liver weights and liver weight-to-body weight ratio were increased in KK/HlJ diabetic mice; however, these values were decreased following treatment with RHL. Compared with the C57BL/J control, KK/HlJ diabetic mice had a significantly lower level of SOD and GSH-px in their livers, but had a significantly higher level of MDA. However, these effects were ameliorated by RHL. Hepatic adipose infiltration was observed in KK/HlJ mice, but not in C57BL/J mice. RHL decreased the incidence of hepatic adipose infiltration and significantly decreased the expression of TNF-α, IL-6, NF-κB, SREBP-1c, and Fas, as well as the phosphorylation of NF-κB in the liver. In conclusion, RHL can improve hepatic function by decreasing hepatic adipose infiltration and the expression of inflammatory factors.

Antitumor efficacy of lidamycin against human multiple myeloma RPMI 8226 cells and the xenograft in nonobese diabetic/severe combined immunodeficiency mice.

AIMS: The aim of this study is to explore the antitumor efficacy of lidamycin (LDM) against human multiple myelomas (MM). MATERIALS AND METHODS: Human MM RPMI 8226 cells and the xenograft model in nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice were used to examine the antitumor activity of LDM. RESULTS: Notably, LDM markedly suppressed the growth of human MM RPMI 8226 xenograft in NOD/SCID mice. In vitro, there was a significant reduction in cell proliferation after treatment with LDM. The overall growth inhibition correlated with the increase of apoptotic cells. The apoptosis-related proteins including caspase-3, 7, and 9 were activated, and poly adenosine diphosphate-ribose polymerase was cleaved. Further investigation revealed that cellular Bcl-2 and survivin decreased, whereas the level of Bax increased in the LDM-treated cells. CONCLUSIONS: LDM is highly effective against the growth of MM xenograft in NOD/SCID mice. The potent apoptosis.inducing effect of LDM may be mediated through caspase. and mitochondria.dependent pathway.

Effects of rhein lysinate on D-galactose-induced aging mice.

The aim of the present study was to investigate the anti-aging effects of rhein lysinate (RHL), and to explore its mechanism of action in a D-galactose-induced aging mouse model. Aging was induced by D-galactose (100 mg/kg/day) that was subcutaneously injected to animals for 8 weeks. RHL was simultaneously administered once a day by intragastric gavage. The appetite, mental condition, body weight and organ index of the mice were monitored. Superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were determined, and the levels of malondialdehyde (MDA) in the liver, kidney and serum were measured by appropriate assay kits. Western blot analysis was used to detect proteins associated with age. The results indicated that RHL may improve the appetite, mental state and organ conditions of the model mice, improve the activities of SOD and GSH-Px, reduce MDA levels and modulate the expression of age-associated proteins (Sirtuin 1, p21 and p16) in D-galactose-induced mice. Therefore, RHL may be effective at suppressing the aging process through a combination of enhancing antioxidant activity, scavenging free radicals and modulating aging-associated gene expression.

Antitumor activity of rhein lysinate against human glioma U87 cells in vitro and in vivo.

In previous studies, we demonstrated that rhein lysinate (RHL), the salt of rhein and lysine that is easily dissolved in water, inhibited the growth of tumor cells derived from breast and ovarian cancer, hepatocellular carcinoma, cervical cancer and lung carcinoma. Based on these observations, human glioma U87 cells and a xenograft model in BALB/c nude mice were used to examine the antitumor activity of RHL against human glioma. Notably, RHL statistically significantly suppressed the growth of human glioma U87 xenografts in BALB/c nude mice. In vitro, there was a significant reduction in cell proliferation after treatment with RHL in a dose- and time-dependent manner. The overall growth inhibition was correlated with the increase in reactive oxygen species (ROS) production and cell apoptosis. The apoptosis- and cell cycle-related proteins including BAX and Bim were increased, whereas Bcl-2 and cyclin D were decreased in the RHL-treated cells. The results demonstrated that RHL is highly effective against the growth of human glioma U87 xenografts in BALB/c nude mice. The potent antitumor activity of RHL may be mediated through downregulation of Bcl-2 and cyclin D expression and upregulation of BAX and Bim expression.

Protective effect of gastrodin on bile duct ligation-induced hepatic fibrosis in rats.

Gastrodin has been showed to possess many beneficial physiological functions, including protection against inflammation and oxidation and apoptosis. Studies showed inflammation and oxidation play important roles in producing liver damage and initiating hepatic fibrogenesis. However, it has not been reported whether gastrodin has a protective effect against hepatic fibrosis or not. This is first ever made attempts to test gastrodin against liver fibrosis in bile duct ligation (BDL) rats. The aim of the present study is to evaluate the effect of gastrodin on BDL-induced hepatic fibrosis in rats. BDL rats were divided into two groups, BDL alone group, and BDL-gastrodin group treated with gastrodin (5 mg/ml in drinking water). The effects of gastrodin on BDL-induced hepatic injury and fibrosis in rats were estimated by assessing serum, urine, bile and liver tissue biochemistry followed by liver histopathology (using hematoxylin & eosin and sirius red stain) and hydroxyproline content measurement. The results showed that gastrodin treatment significantly reduced collagen content, bile duct proliferation and parenchymal necrosis after BDL. The serum alanine aminotransferase (ALT) and serum aspartate aminotransferase (AST) decreased with gastrodin treatment by 15.1 and 23.6 percent respectively in comparison to BDL group did not receive gastrodin. Gastrodin also significantly increased the level of serum high density lipoprotein (HDL) by 62.5 percent and down-regulated the elevated urine total bilirubin (TBIL) by 56.5 percent, but had no effect on total bile acid (TBA) in serum, bile and liver tissues. The immunohistochemical assay showed gastrodin remarkably reduced the expressions of CD68 and NF-κB in BDL rats. Hepatic SOD levels, depressed by BDL, were also increased by gastrodin by 8.4 percent. In addition, the increases of hepatic MDA and NO levels in BDL rats were attenuated by gastrodin by 31.3 and 38.7 percent separately. Our results indicate that gastrodin significantly attenuated the severity of BDL-induced hepatic injury and fibrosis by attenuating oxidative stress and inflammation. Taken together, these findings suggest that gastrodin might be an effective antifibrotic drug in cholestatic liver disease.

Protective effect of bicyclol against bile duct ligation-induced hepatic fibrosis in rats.

AIM: To evaluate the protective effect of bicyclol against bile duct ligation (BDL)-induced hepatic fibrosis in rats. METHODS: Sprague-Dawley male rats underwent BDL and sham-operated animals were used as healthy controls. The BDL rats were divided into two groups which received sterilized PBS or bicyclol (100 mg/kg per day) orally for two consecutive weeks. Serum, urine and bile were collected for biochemical determinations. Liver tissues were collected for histological analysis and a whole genome oligonucleotide microarray assay. Reverse transcription-polymerase chain reaction and Western blotting were used to verify the expression of liver fibrosis-related genes. RESULTS: Treatment with bicyclol significantly reduced liver fibrosis and bile duct proliferation after BDL. The levels of alanine aminotransferase (127.7 ± 72.3 vs 230.4 ± 69.6, P < 0.05) and aspartate aminotransferase (696.8 ± 232.6 vs 1032.6 ± 165.8, P < 0.05) were also decreased by treatment with bicyclol in comparison to PBS. The expression changes of 45 fibrogenic genes and several fibrogenesis-related pathways were reversed by bicyclol in the microarray assay. Bicyclol significantly reduced liver mRNA and/or protein expression levels of collagen 1a1, matrix metalloproteinase 2, tumor necrosis factor, tissue inhibitors of metalloproteinases 2, transforming growth factor-ß1 and α-smooth muscle actin. CONCLUSION: Bicyclol significantly attenuates BDL-induced liver fibrosis by reversing fibrogenic gene expression. These findings suggest that bicyclol might be an effective anti-fibrotic drug for the treatment of cholestatic liver disease.

Gambogic Acid lysinate induces apoptosis in breast cancer mcf-7 cells by increasing reactive oxygen species.

Gambogic acid (GA) inhibits the proliferation of various human cancer cells. However, because of its water insolubility, the antitumor efficacy of GA is limited. Objectives. To investigate the antitumor activity of gambogic acid lysinate (GAL) and its mechanism. Methods. Inhibition of cell proliferation was determined by MTT assay; intracellular ROS level was detected by staining cells with DCFH-DA; cell apoptosis was determined by flow cytometer and the mechanism of GAL was investigated by Western blot. Results. GAL inhibited the proliferation of MCF-7 cells with IC50 values 1.46 µmol/L comparable with GA (IC50, 1.16 µmol/L). GAL promoted the production of ROS; however NAC could remove ROS and block the effect of GAL. GAL inhibited the expression of SIRT1 but increased the phosphorylation of FOXO3a and the expression of p27Kip1. At knockdown of FOXO3a, cell apoptosis induced by GAL can be partly blocked. In addition it also enhanced the cleavage of caspase-3. Conclusions. GAL inhibited MCF-7 cell proliferation and induced MCF-7 cell apoptosis by increasing ROS level which could induce cell apoptosis by both SIRT1/FOXO3a/p27Kip1 and caspase-3 signal pathway. These results suggested that GAL might be useful as a modulation agent in cancer chemotherapy.

The protection of Rhein lysinate to liver in diabetic mice induced by high-fat diet and streptozotocin.

Rhein lysinate (RHL) is the salt of lysine and rhein and the objective of this study was to investigate the protection of RHL to liver in diabetic mice. The model of type 2 diabetes was established by high-fat diet and streptozotocin treatment. Malondialdehyde, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were measured using a spectrophotometer. Inflammatory factors (TNF-α and IL-6) and related proteins (ERK1/2 and SREBP-1c) were analyzed by Western blot. Tissue profile was determined by hematoxylin and eosin staining and accumulation of fat was examined by Nile red staining. The results indicated that plasma glucose levels of type 2 diabetic mice were over 13.9 mM. Compared with model group, plasma glucose levels were decreased, however insulin levels were increased in RHL (25 and 50 mg/kg)-treated group. Elevated plasma triglyceride and cholesterol were also markedly attenuated after RHL treatment. The activities of SOD and GSH-Px of livers were increased after RHL treatment. Livers of RHL-treated mice had more normal structure and less steatosis than that of diabetic mice. Moreover, RHL decreased the expression of TNF-α and IL-6 and the phosphorylation of SREBP-1c and ERK1/2. In conclusion, RHL has a noticeable hepatic protection in diabetic mice.

KNDC1 knockdown protects human umbilical vein endothelial cells from senescence.

KNDC1 (kinase noncatalytic C-lobe domain containing 1), a brain-specific Ras guanine nucleotide exchange factor, controls the negative regulation of neuronal dendrite growth. However, the effect of KNDC1 on cellular senescence remains to be elucidated. The present study investigated the impact of KNDC1 knockdown on human endothelial cell senescence and the mechanisms underlying this effect. Human umbilical vein endothelial cells (HUVECs) cultured in vitro were used as a model of biological aging. Senescence­associated ß-galactosidase staining was used to detect cellular senescence and flow cytometry was employed to determine cell cycle progression. Quantitative polymerase chain reaction (qPCR) and western blot analysis were utilized to investigate mRNA transcription and protein expression. In the HUVECs, a senescence-like phenotypes developed with increasing passage number in vitro, which were associated with a progressive increase in the transcription and expression of KNDC1. KNDC1 knockdown promoted cell proliferation and partially reversed cellular senescence and cell cycle arrest in the G0/G1 phase in aging HUVECs. Investigations into the mechanism underlying this effect demonstrated that KNDC1 knockdown promoted HUVEC proliferation via the extracellular signal-regulated kinase signaling pathway and delayed HUVEC senescence by inhibiting the p53-p21-p16 transduction cascade. In addition, the promotion of the capillary tube network formation and the increased expression of endothelial nitric oxide synthase revealed that the activity and function of endothelial cells were enhanced. In conclusion, KNDC1 knockdown delayed endothelial cell senescence and promoted HUVEC activity and function. These results demonstrated that KNDC1 may be a novel therapeutic target for the development of agents to extend human life.

Synergy of Taxol and rhein lysinate associated with the downregulation of ERK activation in lung carcinoma cells.

In previous studies we observed that rhein lysinate (RHL), a salt of rhein and lysine that is easily dissolved in water, inhibited the growth of tumor cells in breast cancer, ovarian cancer, hepatocellular carcinoma and cervical cancer. The present study aimed to investigate the effects of RHL on H460 and A549 non-small cell lung cancer (NSCLC) cells using a combination of RHL and Taxol. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay was used to determine the growth inhibition effect of the drugs in the H460 and A549 cells. Cell apoptosis was analyzed by flow cytometry combined with fluorescein-isothiocyanate-Annexin V/propidium iodide (PI) staining. The expression levels of proteins were detected by western blotting. There was a significant reduction in the proliferation of the NSCLC cell lines treated with a combination of Taxol and RHL. The overall growth inhibition was directly correlated with apoptotic cell death. RHL potentiated Taxol-induced cell killing by reducing extracellular signal-regulated kinase (ERK) activity and increasing the levels of cleaved poly(ADP-ribose) polymerase (PARP) and caspase-3. Notably, the results for the Bcl-2 and NF-κB proteins also showed downregulation in the combined treatment group compared with the single-agent treatment and the untreated control groups. The present results showed that RHL potentiates the growth inhibition induced by Taxol in NSCLC cells and showed that this synergy may be associated with the downregulation of ERK activation.

Bortezomid enhances the efficacy of lidamycin against human multiple myeloma cells.

The proteasome inhibitor bortezomib has been applied successfully to treat multiple myeloma (MM). Its synergistic effects with other anticancer drugs have been studied widely. In the present study, it was found that lidamycin (LDM), a member of the enediyne antibiotic family, showed much more potent cytotoxicity than bortezomib to MM cell lines: U266 and SKO-007. Here, we investigated the potential synergy of bortezomib and LDM on MM cells. The results showed that cotreatment of bortezomib and LDM synergistically induced cytotoxicity and apoptosis in MM cell lines, followed by enhanced caspase-3 cleavage and degradation of poly-ADP-ribose polymerase together with the decreased nuclear factor-κB protein. These two drugs synergistically induced apoptosis, which was associated with enhanced activation of two mitogen-activated protein kinases: p38 mitogen-activated protein kinase and c-Jun NH(2)-terminal kinase. Moreover, bortezomib plus LDM synergistically induced apoptosis was also associated with downregulation of extracellular signal-regulated kinase, and induction of endoplasmic reticulum stress response. Overall, our results indicate that the combined regimen of bortezomib and LDM might be a potential therapeutic remedy for the treatment of MM.

Rhein lysinate inhibits monocyte adhesion to human umbilical vein endothelial cells by blocking p38 signaling pathway.

The objective of this study was to investigate the effect of rhein lysinate (RHL) on monocyte adhesion and its mechanism. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to determine the growth inhibition by drugs. The monocyte chemoattractant protein (MCP)-1 levels were assayed using MCP-1 ELISA. The expression of proteins was detected by Western blotting analysis. The results indicated that RHL inhibited monocyte adhesion in a dose- and time-dependent manner. RHL (<20 µmol/L) and lipopolysaccharide (LPS) had no effect on viability of human umbilical vein endothelial cells. Therefore, 20 µmol/L RHL was selected for this study. RHL inhibited secretion of MCP-1 induced by LPS and expression of intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1. In the meantime, both RHL and p38 inhibitor (SB203580) inhibited phosphorylation of p38 and mitogen-activated protein kinase-activated protein kinase-2 (MAPKAPK-2) and transcription and expression of ICAM-1 and VCAM-1. In conclusion, RHL inhibits the transcription and expression of ICAM-1 and VCAM-1 by the p38/MAPKAPK-2 signaling pathway, and the effect of RHL on transcription and expression of ICAM-1 and VCAM-1 is similar to p38 inhibitor. RHL could be a prophylactic drug for atherosclerosis.