The oxidized phospholipid PGPC impairs endothelial function by promoting endothelial cell ferroptosis via FABP3.

Ferroptosis is a novel cell death mechanism that is mediated by iron-dependent lipid peroxidation. It may be involved in atherosclerosis development. Products of phospholipid oxidation play a key role in atherosclerosis. 1-palmitoyl-2-glutaroyl-sn-glycero-3-phosphocholine (PGPC) is a phospholipid oxidation product present in atherosclerotic lesions. It remains unclear whether PGPC causes atherosclerosis by inducing endothelial cell ferroptosis. In this study, human umbilical vein endothelial cells (HUVECs) were treated with PGPC. Intracellular levels of ferrous iron, lipid peroxidation, superoxide anions (O2•-), and glutathione were detected, and expression of fatty acid binding protein-3 (FABP3), glutathione peroxidase 4 (GPX4), and CD36 were measured. Additionally, the mitochondrial membrane potential (MMP) was determined. Aortas from C57BL6 mice were isolated for vasodilation testing. Results showed that PGPC increased ferrous iron levels, the production of lipid peroxidation and O2•-, and FABP3 expression. However, PGPC inhibited the expression of GPX4 and glutathione production and destroyed normal MMP. These effects were also blocked by ferrostatin-1, an inhibitor of ferroptosis. FABP3 silencing significantly reversed the effect of PGPC. Furthermore, PGPC stimulated CD36 expression. Conversely, CD36 silencing reversed the effects of PGPC, including PGPC-induced FABP3 expression. Importantly, E06, a direct inhibitor of the oxidized 1-palmitoyl-2-arachidonoyl-phosphatidylcholine IgM natural antibody, inhibited the effects of PGPC. Finally, PGPC impaired endothelium-dependent vasodilation, ferrostatin-1 or FABP3 inhibitors inhibited this impairment. Our data demonstrate that PGPC impairs endothelial function by inducing endothelial cell ferroptosis through the CD36 receptor to increase FABP3 expression. Our findings provide new insights into the mechanisms of atherosclerosis and a therapeutic target for atherosclerosis.

Simvastatin inhibits POVPC-mediated induction of endothelial-to-mesenchymal cell transition.

Endothelial-to-mesenchymal transition (EndMT), the process by which an endothelial cell (EC) undergoes a series of molecular events that result in a mesenchymal cell phenotype, plays an important role in atherosclerosis. 1-Palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphocholine (POVPC), derived from the oxidation of 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphatidylcholine, is a proinflammatory lipid found in atherosclerotic lesions. Whether POVPC promotes EndMT and how simvastatin influences POVPC-mediated EndMT remains unclear. Here, we treated human umbilical vein ECs with POVPC, simvastatin, or both, and determined their effect on EC viability, morphology, tube formation, proliferation, and generation of NO and superoxide anion (O2•-). Expression of specific endothelial and mesenchymal markers was detected by immunofluorescence and immunoblotting. POVPC did not affect EC viability but altered cellular morphology from cobblestone-like ECs to a spindle-like mesenchymal cell morphology. POVPC increased O2- generation and expression of alpha-smooth muscle actin, vimentin, Snail-1, Twist-1, transforming growth factor-beta (TGF-ß), TGF-ß receptor II, p-Smad2/3, and Smad2/3. POVPC also decreased NO production and expression of CD31 and endothelial NO synthase. Simvastatin inhibited POVPC-mediated effects on cellular morphology, production of O2•- and NO, and expression of specific endothelial and mesenchymal markers. These data demonstrate that POVPC induces EndMT by increasing oxidative stress, which stimulates TGF-ß/Smad signaling, leading to Snail-1 and Twist-1 activation. Simvastatin inhibited POVPC-induced EndMT by decreasing oxidative stress, suppressing TGF-ß/Smad signaling, and inactivating Snail-1 and Twist-1. Our findings reveal a novel mechanism of atherosclerosis that can be inhibited by simvastatin.

Associations of coenzyme Q10 with endothelial function in hemodialysis patients.

BACKGROUND: Endothelial dysfunction is common in patients undergoing hemodialysis (HD). However, little is known about the relationship between endothelial dysfunction and coenzyme Q10 (CoQ10) levels in HD patients. METHODS: Eligible HD patients were enrolled in this study according to prespecified inclusion and exclusion criteria. Endothelial function was assessed by brachial artery flow-mediated dilation (FMD). Plasma CoQ10, serum malondialdehyde (MDA) and 8-hydroxydeoxyguanosine (8-OHdG) levels were measured. The potential confounders identified by univariate analyses (P < 0.15) were selected in a stepwise multiple regression model. RESULTS: In total, 111 HD patients were enrolled in this study. The mean CoQ10 level was 633.53 ± 168.66 ng/mL, and endothelial dysfunction was prevalent (91.0%) using a cut-off value of 10% FMD. A significant correlation was observed between FMD and plasma CoQ10 level (r = 0.727, P < 0.001). After adjusting for potential parameters, a stepwise multivariate linear regression analysis revealed that CoQ10 level was an independent predictor of FMD (ß = 0.018, P < 0.001). When CoQ10 was dichotomized using the median value (639.74 ng/mL), the conclusion remained unchanged (ß = 0.584, P < 0.001). Pearson's correlation analyses revealed that plasma CoQ10 level was negatively correlated with MDA (r = -0.48, P < 0.001) and 8-OHdG (r = -0.43, P < 0.001) levels. CONCLUSION: Our data demonstrate that impaired brachial artery FMD was common in HD patients. CoQ10 level was independently associated with FMD, and oxidative stress may constitute a link between CoQ10 level and endothelial dysfunction in these patients.

Synergistic antitumor activity of sorafenib and artesunate in hepatocellular carcinoma cells.

Sorafenib is currently the standard chemotherapy drug for treatment of advanced hepatocellular carcinoma (HCC). But its efficacy requires improvement, it is imperative to seek therapeutic strategies that combine sorafenib with other anticancer agents. In this study we investigated the synergistic anticancer effect of combining sorafenib and artesunate, an anti-malaria drug derivative, against HCC in vitro and in vivo. We first showed that artesunate (1-100 µM) alone dose-dependently inhibited the proliferation of five HCC cell lines tested with IC50 values of around 100 µM. Artesunate treatment dose-dependently increased the ROS level in both HuH7 and Hep3B cells; addition of NAC significantly ameliorated the antiproliferation effect of artesunate against HuH7 and Hep3B cells. Then we demonstrated that combination of sorafenib and artesunate exerted synergistic antiproliferation effect and induced synergistic apoptosis in HCC cell lines. In nude mice bearing Hep3B xenografts, combined administration of sorafenib and artesunate significantly enhanced the suppression on tumor growth. We further revealed that sorafenib dose-dependently decreased the levels of p-ERK and p-STAT3, whereas artesunate markedly increased the levels of p-ERK and p-STAT3 in HuH7 and Hep3B cells. When used in combination, sorafenib abolished artesunate-elevated levels of p-STAT3 and p-ERK. Moreover, pharmacological inhibition of ERK by inhibitor PD0325901 or STAT3 by inhibitor Stattic markedly enhanced the anticancer activity of artesunate, suggesting that suppression of ERK and STAT3 signaling by sorafenib contributes to the synergistic anticancer activity against HCC caused by combination of sorafenib and artesunate. Taken together, our results provide an evidence for possible use of sorafenib plus artesunate or artemisinin analogs for treatment of HCC in the future.

miR-191 Inhibition Induces Apoptosis Through Reactivating Secreted Frizzled-Related Protein-1 in Cholangiocarcinoma.

BACKGROUND/AIMS: Cholangiocarcinoma (CCA) is one of the most common malignant tumors of the biliary tract originating from biliary epithelial cells. Although many therapeutic strategies have been developed to treat CCA, the survival rate for CCA patients is still quite low. Thus it is urgent to elucidate the pathogenesis of CCA and to explore novel therapeutic targets. miR-191 has been shown to be associated with many human solid cancers, but the function of miR-191 in CCA is still poorly understood. METHODS: We first investigated the expression level of miR-191 in human CCA tissues and cell lines with quantitative real-time PCR (qRT-PCR). The effects of miR-191 on CCA cells were determined by Cell Counting Kit-8 assay, colony formation assay and acridine orange/ethidium bromide staining. Finally, we utilized qRT-PCR, western blot and luciferase reporter assays to verify the miR-191 target gene. RESULTS: We showed that miR-191 was up-regulated in CCA cell lines and patients. Knockdown of miR-191 by transfection of its inhibitor sequence blocked RBE cells viability and induced apoptosis of RBE cells. Both qRT-PCR and western blot analysis showed that the secreted frizzled-related protein-1 (sFRP1) level was negatively correlated with that of miR-191. Luciferase assay validated that sFRP1 was a direct target of miR-191. Moreover, knockdown of miR-191 led to suppression of Wnt/ß-catenin signaling activation. Co-transfection of sFRP1 small interfering RNA (siRNA) and miR-191 inhibitor re-activated the Wnt/ß-catenin signaling pathway as detected by an increased level of ß-catenin and phosphorylation of GSK-3ß, and restored the expression of survivin and c-myc in RBE cells. Co-transfection of sFRP1 siRNA with miR-191 inhibitor restored the colony formation ability and viability of RBE cells. CONCLUSION: Taken together, our results demonstrate a novel insight into miR-191 biological function in CCA. Our findings suggest that miR-191 is a potential therapeutic target of CCA treatment.

Capsaicin enhances the antitumor activity of sorafenib in hepatocellular carcinoma cells and mouse xenograft tumors through increased ERK signaling.

Sorafenib, a small inhibitor of tyrosine protein kinases, is currently the standard chemotherapy drug for the treatment of advanced hepatocellular carcinoma (HCC). Although sorafenib improves the survival of HCC patients, its efficacy is not optimal and requires further improvement. Capsaicin, the major active component of chili peppers from the genus Capsicum, is not only the agonist of TRPV1 channel, but also displays antitumor activity and enhances the sensitivity of cancer cells to cytotoxic drugs. In this study, we investigated the antitumor effects of combined sorafenib and capsaicin on HCC cells in vitro and xenograft tumors. Treatment with capsaicin alone dose-dependently inhibited the proliferation of the HCC cell lines PLC/PRF/7, HuH7 and HepG2 with IC50 values of 137, 108 and 140.7 µmol/L, respectively. No obvious expression of TRPV1 channel was detected in the 3 HCC cell lines and TRPV1 channel blockers did not alleviate the cytotoxicity of capsaicin. By contrast, combining capsaicin and sorafenib significantly enhanced the suppression on cell proliferation, achieving a high-level synergistic effect (inhibition rates over 50%) and promoting HCC cell apoptosis. In nude mice with PLC/PRF/5 xenografts, combined administration of capsaicin and sorafenib significantly enhanced the suppression on tumor growth without apparent gross toxicity compared to either agent alone. Mechanistically, capsaicin (10-200 µmol/L) dose-dependently increased the levels of phosphorylated ERK (p-ERK) in PLC/PRF/5 cells, thus leading to enhanced sorafenib sensitivity and a synergistic suppression on the tumor cells. Taken together, our results suggest that capsaicin-increased phosphorylation of ERK contributes to the enhanced antitumor activity of sorafenib, and capsaicin may be useful in improving the efficacy of sorafenib for the treatment of HCC.

Sirt1 is involved in decreased bone formation in aged apolipoprotein E-deficient mice.

AIM: Apolipoprotein E (ApoE) plays an important role in the transport and metabolism of lipids. Recent studies show that bone mass is increased in young apoE(-/-) mice. In this study we investigated the bone phenotype and metabolism in aged apoE(-/-) mice. METHODS: Femurs and tibias were collected from 18- and 72-week-old apoE(-/-) mice and their age-matched wild-type (WT) littermates, and examined using micro-CT and histological analysis. Serum levels of total cholesterol, oxidized low-density lipoprotein (ox-LDL) and bone turnover markers were measured. Cultured bone mesenchymal stem cells (BMSCs) from tibias and femurs of 18-week-old apoE(-/-) mice were used in experiments in vitro. The expression levels of Sirt1 and Runx2 in bone tissue and BMSCs were measured using RT-PCR and Western blot analysis. RESULTS: Compared with age-matched WT littermates, young apoE(-/-) mice exhibited high bone mass with increased bone formation, accompanied by higher serum levels of bone turnover markers OCN and TRAP5b, and higher expression levels of Sirt1, Runx2, ALP and OCN in bone tissue. In contrast, aged apoE(-/-) mice showed reduced bone formation and lower bone mass relative to age-matched WT mice, accompanied by lower serum OCN levels, and markedly reduced expression levels of Sirt1, Runx2, ALP and OCN in bone tissue. After BMSCs were exposed to ox-LDL (20 µg/mL), the expression of Sirt1 and Runx2 proteins was significantly increased at 12 h, and then decreased at 72 h. Treatment with the Sirt1 inhibitor EX527 (10 µmol/L) suppressed the expression of Runx2, ALP and OCN in BMSCs. CONCLUSION: In contrast to young apoE(-/-) mice, aged apoE(-/-) mice showe lower bone mass than age-matched WT mice. Long-lasting exposure to ox-LDL decreases the expression of Sirt1 and Runx2 in BMSCs, which may explain the decreased bone formation in aged apoE(-/-) mice.

[Factors influencing the clinical pregnancy rate following intrauterine insemination].

OBJECTIVE: To investigate the factors that affect the clinical pregnancy rate after intrauterine insemination (IUI). METHODS: We retrospectively analyzed the clinical data of 611 IUI cycles and analyzed the relationship of the clinical pregnancy rate after IUI with the female age, infertility duration, type of infertility, cycle number, cycle protocol, thickness and type of endometrium, and semen parameters before processing. RESULTS: The clinical pregnancy rate was significantly higher in the ovulation induction than in the natural ovulation cycles (23.03% vs 11.03%, P < 0.01), but lower in the 4th cycle and above than in the 1st, 2nd, and 3rd cycles (2.04% vs 21.30%, 18.13%, and 12.67%, P < 0.01). Marked decreases were found in the clinical pregnancy rate in the females aged ≥ 40 years and the cases with pre-processing total progressively motile sperm count (TPMSC) < 10 x 10(6), progressive motile sperm < 20%, or morphologically normal sperm < 2% (all P < 0.05). Logistic regression analysis revealed the cycle protocol, cycle number, and percentage of progressively motile sperm as three predictive variables affecting the clinical pregnancy rate after IUI (P < 0.05). CONCLUSION: The cycle protocol, cycle number, percentage of progressively motile sperm, female age, TPMSC, and sperm morphology are the main factors affecting the clinical pregnancy rate following IUI, while infertility duration, type of infertility, and thickness and type of endometrium exert little influence.

Highly variable recessive lethal or nearly lethal mutation rates during germ-line development of male Drosophila melanogaster.

Each cell of higher organism adults is derived from a fertilized egg through a series of divisions, during which mutations can occur. Both the rate and timing of mutations can have profound impacts on both the individual and the population, because mutations that occur at early cell divisions will affect more tissues and are more likely to be transferred to the next generation. Using large-scale multigeneration screening experiments for recessive lethal or nearly lethal mutations of Drosophila melanogaster and recently developed statistical analysis, we show for male D. melanogaster that (i) mutation rates (for recessive lethal or nearly lethal) are highly variable during germ cell development; (ii) first cell cleavage has the highest mutation rate, which drops substantially in the second cleavage or the next few cleavages; (iii) the intermediate stages, after a few cleavages to right before spermatogenesis, have at least an order of magnitude smaller mutation rate; and (iv) spermatogenesis also harbors a fairly high mutation rate. Because germ-line lineage shares some (early) cell divisions with somatic cell lineage, the first conclusion is readily extended to a somatic cell lineage. It is conceivable that the first conclusion is true for most (if not all) higher organisms, whereas the other three conclusions are widely applicable, although the extent may differ from species to species. Therefore, conclusions or analyses that are based on equal mutation rates during development should be taken with caution. Furthermore, the statistical approach developed can be adopted for studying other organisms, including the human germ-line or somatic mutational patterns.

Central venous catheter infection-induced Henoch-Schönlein purpura in a patient on hemodialysis.

A 69-year-old man, who had been dialyzed using a permanent central venous catheter for 2 years, presented with Henoch-Schönlein purpura and positive perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA). He was diagnosed with catheter-related infection by Staphylococcus aureus. After administration of antibiotic and steroid therapy, purpura disappeared and p-ANCA gradually became negative. This case supports the conclusion that infection can be pathogenesis of the vasculitis, including ANCA-positive HSP. Additionally, impregnation of catheters with antibiotics can be an effective treatment for catheter infections.

Cinobufacini Inhibits Survival and Metastasis of Hepatocellular Carcinoma via c-Met Signaling Pathway.

OBJECTIVE: To investigate the anti-tumor effects of cinobufacini (CINO) on hepatocellular carcinoma (HCC) induced by des-gamma-carboxy-prothrombin (DCP) and to uncover the underlying mechanisms. METHODS: The inhibitory effect of CINO on HCC cell proliferation was evaluated using the cell counting kit-8 method, and the apoptosis rate was quantified using flow cytometry. Immunofluorescence and Western blot analyses were used to investigate the differential expression of proteins associated with cell growth, apoptosis, migration, and invasion pathways after CINO treatment. The therapeutic potential of CINO for HCC was confirmed, and the possibility of combining cinobufacini with c-Met inhibitor for the treatment of primary HCC was further validated by in vivo experiments. RESULTS: Under the induction of DCP, CINO inhibited the activity of HCC cells, induced apoptosis, and inhibited migration and invasion. Upon the induction of DCP, CINO regulated c-Met activation and the activation of the phosphatidylinositol-3 kinase/protein kinase B (PI3K/AKT) and mitogen-activated protein kinase kinase/extracellular signal-regulated kinase (MEK/ERK) pathways. In a mouse model of HCC, CINO exhibited significant antitumor effects by inhibiting the phosphorylation of c-Met and the downstream PI3K/AKT and MEK/ERK pathways in tumor tissues. CONCLUSIONS: CINO inhibited HCC cell growth, promoted apoptosis, and suppressed HCC cell invasion and migration by targeting c-Met and PI3K/AKT and MEK/ERK signaling pathways under DCP induction.

High-density lipoprotein regulates angiogenesis by affecting autophagy via miRNA-181a-5p.

We previously demonstrated that normal high-density lipoprotein (nHDL) can promote angiogenesis, whereas HDL from patients with coronary artery disease (dHDL) is dysfunctional and impairs angiogenesis. Autophagy plays a critical role in angiogenesis, and HDL regulates autophagy. However, it is unclear whether nHDL and dHDL regulate angiogenesis by affecting autophagy. Endothelial cells (ECs) were treated with nHDL and dHDL with or without an autophagy inhibitor. Autophagy, endothelial nitric oxide synthase (eNOS) expression, miRNA expression, nitric oxide (NO) production, superoxide anion (O2•-) generation, EC migration, and tube formation were evaluated. nHDL suppressed the expression of miR-181a-5p, which promotes autophagy and the expression of eNOS, resulting in NO production and the inhibition of O2•- generation, and ultimately increasing in EC migration and tube formation. dHDL showed opposite effects compared to nHDL and ultimately inhibited EC migration and tube formation. We found that autophagy-related protein 5 (ATG5) was a direct target of miR-181a-5p. ATG5 silencing or miR-181a-5p mimic inhibited nHDL-induced autophagy, eNOS expression, NO production, EC migration, tube formation, and enhanced O2•- generation, whereas overexpression of ATG5 or miR-181a-5p inhibitor reversed the above effects of dHDL. ATG5 expression and angiogenesis were decreased in the ischemic lower limbs of hypercholesterolemic low-density lipoprotein receptor null (LDLr-/-) mice when compared to C57BL/6 mice. ATG5 overexpression improved angiogenesis in ischemic hypercholesterolemic LDLr-/- mice. Taken together, nHDL was able to stimulate autophagy by suppressing miR-181a-5p, subsequently increasing eNOS expression, which generated NO and promoted angiogenesis. In contrast, dHDL inhibited angiogenesis, at least partially, by increasing miR-181a-5p expression, which decreased autophagy and eNOS expression, resulting in a decrease in NO production and an increase in O2•- generation. Our findings reveal a novel mechanism by which HDL affects angiogenesis by regulating autophagy and provide a therapeutic target for dHDL-impaired angiogenesis.

Endothelial extracellular vesicles induce acute lung injury via follistatin-like protein 1.

Cardiopulmonary bypass has been speculated to elicit systemic inflammation to initiate acute lung injury (ALI), including acute respiratory distress syndrome (ARDS), in patients after cardiac surgery. We previously found that post-operative patients showed an increase in endothelial cell-derived extracellular vesicles (eEVs) with components of coagulation and acute inflammatory responses. However, the mechanism underlying the onset of ALI owing to the release of eEVs after cardiopulmonary bypass, remains unclear. Plasma plasminogen-activated inhibitor-1 (PAI-1) and eEV levels were measured in patients with cardiopulmonary bypass. Endothelial cells and mice (C57BL/6, Toll-like receptor 4 knockout (TLR4-/-) and inducible nitric oxide synthase knockout (iNOS-/-)) were challenged with eEVs isolated from PAI-1-stimulated endothelial cells. Plasma PAI-1 and eEVs were remarkably enhanced after cardiopulmonary bypass. Plasma PAI-1 elevation was positively correlated with the increase in eEVs. The increase in plasma PAI-1 and eEV levels was associated with post-operative ARDS. The eEVs derived from PAI-1-stimulated endothelial cells could recognize TLR4 to stimulate a downstream signaling cascade identified as the Janus kinase 2/3 (JAK2/3)-signal transducer and activator of transcription 3 (STAT3)-interferon regulatory factor 1 (IRF-1) pathway, along with iNOS induction, and cytokine/chemokine production in vascular endothelial cells and C57BL/6 mice, ultimately contributing to ALI. ALI could be attenuated by JAK2/3 or STAT3 inhibitors (AG490 or S3I-201, respectively), and was relieved in TLR4-/- and iNOS-/- mice. eEVs activate the TLR4/JAK3/STAT3/IRF-1 signaling pathway to induce ALI/ARDS by delivering follistatin-like protein 1 (FSTL1), and FSTL1 knockdown in eEVs alleviates eEV-induced ALI/ARDS. Our data thus demonstrate that cardiopulmonary bypass may increase plasma PAI-1 levels to induce FSTL1-enriched eEVs, which target the TLR4-mediated JAK2/3/STAT3/IRF-1 signaling cascade and form a positive feedback loop, leading to ALI/ARDS after cardiac surgery. Our findings provide new insight into the molecular mechanisms and therapeutic targets for ALI/ARDS after cardiac surgery.

Phylogenetic relationship among East Asian species of the Stegana genus group (Diptera, Drosophilidae).

The phylogenetic relationship among 27 East Asian species of the Stegana genus group was reconstructed using DNA sequences of mitochondrial (COI and ND2) and nuclear (28S) genes. The results lent support to the current generic/subgeneric taxonomic classification in the genus group with the exceptions of the paraphyly of the genus Parastegana and the subgenus Oxyphortica in the genus Stegana. The ancestral areas and divergence times in the genus group were reconstructed/estimated, and accordingly, the biogeographical history of this important clade was discussed. It was proposed that, the evolution of the plant family Fagaceae, especially Quercus, may have played a certain role in facilitating the diversification of the Stegana genus group.

Beneficial effects of short-term calorie restriction against cisplatin-induced acute renal injury in aged rats.

BACKGROUND: The therapeutic use of the antineoplastic drug cisplatin (DDP) in the elderly is limited by its nephrotoxic effects. The aim of this study was to examine the effect of short-term calorie restriction (CR) on DDP-induced nephrotoxicity in aged rats. METHODS: A group of 25-month-old male Sprague-Dawley rats were divided into two groups: ad libitum (AL) and CR, which were fed 60% of the food consumed by AL rats for 8 weeks. The two groups were each further randomly divided into two subgroups: OAL control, OAL+DDP, OCR control, and OCR+DDP. A single dose of DDP (6 mg/kg) was injected intraperitoneally. Functional and structural changes of the kidneys were evaluated quantitatively by biochemical, histopathological, and morphometric analyses. RESULTS: At the end of the 8 weeks, rats in the OCR group lost 14.8% more body mass than rats in the OAL group. Pretreatment with CR had several effects: (1) it reduced the levels of blood urea nitrogen and serum creatinine, (2) it reduced the magnitude of the renal tubular epithelial damage, and (3) it significantly reduced the incidence of activated caspase-3 and TUNEL-positive cells in kidneys injured by DDP. However, SIRT1 had the opposite trend after DDP application between the two groups. CONCLUSIONS: Short-term CR exhibits a renoprotective effect in experimental DDP-induced renal injury, the mechanism of which may involve CR antiapoptotic effects and promotion of SIRT1.

Phylogenetic classification and palm-inflorescence anthophily of the Colocasiomyia zeylanica species group (Diptera: Drosophilidae), with descriptions of five new species.

The zeylanica group is one of the six species groups of the anthophilic genus Colocasiomyia de Meijere in the family Drosophilidae. In addition to two known species, five morphospecies have been recognized as members of this species group but left undescribed formally. In this study, species delimitation of these putatively new species was determined by barcoding of the mitochondrial COI (cytochrome c oxydase subunit I) gene and morphological comparison. Phylogenetic relationships within the genus Colocasiomyia were inferred by a cladistic analysis of 89 morphological characters. Based on the results of these analyses, we redefined the zeylanica species group and established two subgroups within it: the zeylanica subgroup comprised of C. zeylanica, C. nepalensis, C. pinangae sp. nov., C. besaris sp. nov. and C. luciphila sp. nov., and the oligochaeta subgroup of C. oligochaeta sp. nov. and C. grimaldii sp. nov. In addition, we briefly address the anthophilic habits of drosophilid flies using palm (Arecaceae) inflorescences, especially of the zeylanica group, compiling scattered collection records from the Oriental and Papuan regions.

High-density lipoprotein regulates angiogenesis by long non-coding RNA HDRACA.

Normal high-density lipoprotein (nHDL) can induce angiogenesis in healthy individuals. However, HDL from patients with coronary artery disease undergoes various modifications, becomes dysfunctional (dHDL), and loses its ability to promote angiogenesis. Here, we identified a long non-coding RNA, HDRACA, that is involved in the regulation of angiogenesis by HDL. In this study, we showed that nHDL downregulates the expression of HDRACA in endothelial cells by activating WW domain-containing E3 ubiquitin protein ligase 2, which catalyzes the ubiquitination and subsequent degradation of its transcription factor, Kruppel-like factor 5, via sphingosine 1-phosphate (S1P) receptor 1. In contrast, dHDL with lower levels of S1P than nHDL were much less effective in decreasing the expression of HDRACA. HDRACA was able to bind to Ras-interacting protein 1 (RAIN) to hinder the interaction between RAIN and vigilin, which led to an increase in the binding between the vigilin protein and proliferating cell nuclear antigen (PCNA) mRNA, resulting in a decrease in the expression of PCNA and inhibition of angiogenesis. The expression of human HDRACA in a hindlimb ischemia mouse model inhibited the recovery of angiogenesis. Taken together, these findings suggest that HDRACA is involved in the HDL regulation of angiogenesis, which nHDL inhibits the expression of HDRACA to induce angiogenesis, and that dHDL is much less effective in inhibiting HDRACA expression, which provides an explanation for the decreased ability of dHDL to stimulate angiogenesis.

DAP5 ameliorates cisplatin-induced apoptosis of renal tubular cells.

BACKGROUND: Nephrotoxicity of cisplatin limits its clinical application. Cisplatin-induced acute renal tubular epithelial cell apoptosis is one of the major mechanisms of cisplatin nephrotoxicity. Here, the role and regulation of death-associated protein 5 (DAP5) in cisplatin-induced tubular cell apoptosis were investigated. METHODS: After upregulation of DAP5 expression by plasmid transfection and downregulation of DAP5 expression by small interfering RNA in human kidney tubular epithelial cell line (HKC) cells, the degree of cell apoptosis was assessed by flow cytometric analysis. The expression of Bax and Bcl-2 proteins was detected by Western blot analysis. The relationship between the PI3K/Akt/mTOR signaling pathway and DAP5 was also evaluated. RESULTS: During cisplatin-induced apoptosis in HKC cells, DAP5 underwent proteolytic fragmentation, yielding an 86-kDa species, DAP5/p86. Overexpression of DAP5/p97 and DAP5/p86 increased the translation of Bcl-2 and reduced the extent of cisplatin-induced apoptosis. Knockdown of DAP5 expression using small interfering RNA decreased the translation of Bcl-2 and increased the degree of apoptosis. Neither manipulation affected the expression of Bax. DAP5 expression was positively regulated by the PI3K/Akt/mTOR signaling pathway. CONCLUSION: Collectively, the results from the present study revealed a new role for DAP5 in cisplatin-induced apoptosis: DAP5/p97 and DAP5/p86 enhanced the translation of the anti-apoptotic protein Bcl-2 and inhibited cisplatin-induced apoptosis. The PI3K/Akt/mTOR signaling pathway may positively regulate the expression of DAP5.

High glucose-induced hypertrophy of mesangial cells is reversed by connexin43 overexpression via PTEN/Akt/mTOR signaling.

BACKGROUND: Hypertrophy of glomerular mesangial cells (GMC) is one of the earliest pathological abnormalities in diabetic nephropathy, which correlates with eventual glomerulosclerosis. We have previously proved that this hypertrophy is mediated by downregulation of connexin43 (Cx43) and dysfunction of gap junctional intercellular communication, but the mechanism involved is still unclear. This study aims to investigate whether PTEN/Akt/mammalian target of rapamycin (mTOR) was involved as the downstream molecular signaling of Cx43 in regulating high glucose-induced GMC hypertrophy. METHODS: GMC were isolated from male Wistar rats at the age of 3 months. Gene transfer technique was used to upregulate Cx43 in GMC, which was validated by western blot and immunofluorescent staining. Forward scatter of flow cytometry and total protein/cell number were examined to testify GMC hypertrophy induced by high glucose (30 mM) and the influence of Cx43 overexpression; western blot was performed to demonstrate the changes of Cx43 and signal protein level and flow cytometry and MTT test were carried out to check cell cycle and proliferation rate, respectively. RESULTS: GMC exposed to a high concentration of glucose presented decreased Cx43, inhibited PTEN, triggered Akt phosphorylation and activated downstream mTOR, leading to stagnancy of cell cycle, decline of proliferation rate and occurrence of hypertrophy. Cx43 overexpression could prevent PTEN inhibition, Akt and mTOR phosphorylation, resulting in restoration of cell cycle and proliferation ability and reversion of GMC hypertrophy. GMC with Cx43 inhibition showed similar PTEN/Akt/mTOR change as stimulated by high glucose. CONCLUSION: PTEN/Akt/mTOR signaling stimulated by high concentration of glucose is regulated by Cx43 overexpression, which unveils part of the molecular mechanism of Cx43 in regulating hyperglycemia-induced hypertrophy.

Characteristics and influence factors of pathologic transformation in the subclasses of class IV lupus nephritis.

The study explored the characteristics and correlation factors of transformation in subclasses of class IV lupus nephritis. Patients with class IV lupus nephritis were subjected to repeat biopsies after 6 months of induction treatment. Transformation rate between two subclasses, class IV-S and class IV-G, was compared. Influence Factors of transformation were evaluated. Class IV-G had more severe hypertension and higher score of immunofluorescence index, glomerular active lesions, tubular and vascular lesions. Class IV-S had a higher percentage of glomerular fibrinoid necrosis. Class IV-S appeared a higher rate of transformation to class II than class IV-G (57% vs. 27%). In each subclass, active lesion also showed a higher rate of transformation to class II than active/chronic lesion (IV-G: 41.2% vs. 12.5%; IV-S: 71.4% vs. 42.8%). Patients who maintained class IV had higher blood pressure, obvious proteinuria, declined kidney function, and lower C3 level. Immunosuppressive therapy, urine protein, and vascular lesions were independent risk factors for the pathologic transformation. The rate of transformation in class IV-S was higher than that in class IV-G. The transformation is most likely to benefit from immunosuppressive therapy. Urine protein and vascular lesions are correlated with the transformation in class IV lupus nephritis.