Synergy of Cd Doping and S Vacancies in CdxZn1-xIn2S4 Hierarchical Nanotubes for Highly Improved Visible-Light-Driven H2 Evolution.

Photocatalytic water splitting over semiconductors is believed as a promising avenue to obtain H2 fuel from renewable solar energy. However, developing highly active and non-noble-metal photocatalysts for H2 evolution is still quite challenging to date. In this work, by constructing nanosheet-based nanotubes with Cd-doping and S vacancies, a highly improved visible-light-driven H2 production for ZnIn2S4 is achieved. Unlike nanoflowers aggregated with nanosheets, the nanosheet-assembled hierarchical nanotubes allow multiple scattering and reflection of incident light within the interior space, leading to an enhanced light-harvesting efficiency. Together with the benefits from Cd doping and S-vacancy engineering, including narrowed band gaps, efficient transmission and separation of charge carriers, abundant catalytically active sites, heightened photo-stability and photo-electron reduction capacity, as well as a strong electrostatic attraction to protons, the synthesized S-deficient CdxZn1-xIn2S4 hierarchical nanotubes exhibit an extraordinary photocatalytic H2 evolution capability under visible-light irradiation, delivering an outstanding H2-generation activity of 28.99 mmol·g-1·h-1 (corresponding to an apparent quantum yield of 37.1% at 400 nm), which is much superior to that of CdxZn1-xIn2S4 nanoflowers, Pt-loaded ZnIn2S4 nanotubes, and most ever reported ZnIn2S4-based photocatalysts. Our study could inspire the development of low-cost and high-performance photocatalysts via rational structural design and optimization.

The mediating effects of self-directed learning ability and critical thinking ability on the relationship between learning engagement and problem-solving ability among nursing students in Southern China: a cross-sectional study.

BACKGROUND: Problem-solving ability has been identified as a core competence that nursing students should develop, and it plays a vital role in career development. Therefore, it is necessary to investigate factors related to problem-solving ability and the path relationships among those factors in the context of nursing students. OBJECTIVE: This study aims to identify the factors that affect problem-solving ability, and to investigate path relationships of self-directed learning ability, critical thinking ability, learning engagement, and problem-solving ability among nursing students. DESIGN: A cross-sectional study. SETTINGS: The Department of Nursing at a university located in Shanghai, China. SAMPLE: A total of 540 nursing students with a three-year education program were enrolled in the current study. METHODS: Data were collected by using a structured questionnaire, including general information, learning engagement, self-directed learning ability, critical thinking ability, and problem-solving ability of nursing students. Pearson's correlations were used to explore the relationships between learning engagement, self-directed learning ability, critical thinking ability, and problem-solving ability. The path relationships were analyzed by constructing a structural equation model using AMOS software. RESULTS: Our results showed that learning engagement, self-directed learning ability, and critical thinking ability were positively associated with problem-solving ability. Furthermore, learning engagement did not influence problem-solving ability directly, but it affected problem-solving ability indirectly via self-directed learning ability and critical thinking ability among nursing students. Additionally, the total effects of self-directed learning (0.442) and critical thinking ability (0.581) were more prominent than learning engagement (0.361) on problem-solving ability. CONCLUSIONS: To improve the problem-solving ability of nursing students, nursing educators should develop targeted strategies to enhance learning engagement, self-directed learning ability, and critical thinking ability.

Amodiaquine-induced reproductive toxicity in adult male rats.

Amodiaquine (AQ) is routinely prescribed as an anti-malarial drug. Here, we evaluated AQ-induced toxicity in the male reproductive system. Eighty adult male Sprague-Dawley rats were randomly divided into four groups that received distilled water (control) or daily doses of 5 mg/kg body weight, 10 mg/kg, or 15 mg/kg AQ for 2 weeks. Testes morphology was analyzed using hematoxylin-and-eosin staining, terminal dUTP nicked-end labeling (TUNEL), and immunostaining whereas protein expression was determined by Western blotting. AQ dose-dependently led to abnormal spermatogenesis. Disruption of the blood-testis barrier and increased germ cell apoptosis were observed in all three AQ-treated groups. Interestingly, AQ-induced damage of spermatogenesis recovered over time, based on the survival of promyelocytic leukemia zinc-finger (PLZF)-positive, undifferentiated spermatogonia. Serum levels of luteinizing hormone and testosterone, as well as testicular testosterone levels, were not significantly altered in AQ-treated groups compared with controls. Collectively, our study suggests that AQ exerts substantial acute side effects on the reproductive systems of adult male rats by inducing the apoptosis of differentiating spermatogenic cells and disruption of blood-testis barrier function.

d-galactose causes embryonic development arrest and placental development disorders in mice by increasing ROS and inhibiting SIRT1/FOXO3a axis.

INTRODUCTION: Does an elevation in d-Galactose (D-Gal) levels within the body contribute to abnormal embryonic development and placental dysfunction during pregnancy? METHODS: Mouse embryos were cultivated to the blastocyst stage under varying concentrations of D-Gal. The blastocyst formation rate was measured, and the levels of reactive oxygen species (ROS), sirtuin 1 (SIRT1), and forkhead box O3a (FOXO3a) in blastocysts were assessed. Mice were intraperitoneally injected with either saline or D-Gal with or without SRT1720. On the 14th day of pregnancy, the fetal absorption rate and placental weight were recorded. Placental levels of superoxide dismutase (SOD) and malondialdehyde (MDA) were determined. The expression of senescence-related factors, such as senescence-associated ß-galactosidase (SA-ß-gal) in the placenta was examined, and the expression of placental SIRT1, FOXO3a and p21 was evaluated by immunohistochemistry and Western blotting. RESULTS: D-Gal adversely affects early embryonic development in vitro, resulting in a decreased blastocyst formation rate. Furthermore, D-Gal downregulates SIRT1 and FOXO3a while increasing ROS levels in blastocysts. Concurrently, D-Gal induces placental dysfunction, characterized by an elevated fetal absorption rate, reduced placental weight, diminished SOD activity, and increased MDA content. The senescence-related factor SA-ß-gal was detected in the placenta, along with altered expression of placental SIRT1, FOXO3a, and p21. The SIRT1 agonist SRT1720 mitigated this damage by increasing SIRT1 and FOXO3a expression. DISCUSSION: The inhibition of early embryonic development and placental dysfunction induced by D-Gal may be attributed to the dysregulation of SIRT1. Activating SIRT1 emerges as a potentially effective strategy for alleviating the adverse effects of D-Gal exposure.

Effects of phthalates on human chorionic trophoblast cells and mouse embryonic development.

Phthalate exposure is associated with reproductive health, but the mechanism is unclear. This study used human chorionic trophoblast epithelial cells (HTR8/Svneo cells) and mouse embryos as objects aims to explore the effects of phthalate plasticizers on germ cells and fertility and the possible signalling pathways. In the present study, high concentrations of MEHP for 24 h significantly inhibited the proliferation and viability of HTR8/SVneo cells. Compared with the negative control (NC) group, the MEHP medium and high concentration groups promoted the apoptosis of HTR8/SVneo cells and inhibited the cell cycle, HTR8/SVneo cells were blocked in G1/G0 phase and could not enter S phase, and cell meiosis was inhibited. Western blot experiments showed that there was no difference in the protein expression of wnt inhibitory factor 1 (WIF1) and ß-catenin in HTR8/SVneo cells between the MEHP exposure groups and the NC groups. In vitro embryo culture experiments found that there was no difference in blastocyst formation rate among groups after exposure to DEHP for 2 h. Immunofluorescence showed that the expression of WIF1 decreased in the low concentration group, and there was no difference in the medium and high concentration groups, while the expression of ß-catenin was increased in both the low concentration group and the high concentration group. Our data suggest that exposure to phthalate plasticizers can affect the viability, cell cycle and apoptosis of trophoblast cells, resulting in abnormal expression of the embryonic WIF1/ß-catenin signalling pathway and impaired fertility.

SRT1720 plays a role in oxidative stress and the senescence of human trophoblast HTR8/SVneo cells induced by D-galactose through the SIRT1/FOXO3a/ROS signalling pathway.

D-galactose (D-gal) is a reducing sugar widely distributed in food. In a pregnant animal model exposed to D-gal, D-gal was found to have toxic effects on both the mother and foetus through oxidative stress. However, little is known about the effect of D-gal exposure on the placenta and its underlying mechanism. In this study, we evaluated the effects of D-gal on HTR8/SVneo cells and the mechanisms in vitro. In the present study, the activity of HTR8/SVneo human trophoblasts decreased in a time- and concentration-dependent manner after exposure to D-gal. D-gal resulted in premature senescence of HTR8/SVneo cells, as confirmed by assessing ß-galactosidase (SA-ß-gal) activity and the expression of senescence-related factor p21. We also verified the damage of oxidative stress induced by D-gal by measuring the expression of reactive oxygen species (ROS), sirtuin 1 (SIRT1) and forkhead box O (FOXO) 3a. SRT1720, as a SIRT1 activator, mitigated D-gal-induced oxidative stress and senescence by upregulating SIRT1 and FOXO3a expression and reducing ROS production. Our data suggest that D-gal may induce HTR8/SVneo premature ageing through the SIRT1/FOXO3a/ROS signalling pathway mediated by oxidative stress and that SIRT1 protects cells from this damage.

Does LIN28B gene dysregulation make women more likely to abort?

BACKGROUND: LIN28B plays an important role in early embryonic development, but its role in villous trophoblast implantation and differentiation remains unknown. This study aims to verify the role of LIN28B in trophoblastic villous tissue and cells from women with URSA (unexplained recurrent spontaneous abortion) and artificial termination of pregnancy (negative control, NC). METHODS: The LIN28B gene and its protein expression level were detected with real-time quantitative PCR, Western immunoblotting analysis, and immunocytochemistry. The gene was also overexpressed in chorionic villous cell lines (HTR-8/SVneo and BeWo) to examine its effect on trophoblast function. RESULTS: The expression of LIN28B mRNA and protein of URSA villi was lower than that in the NC group. At the cellular level, overexpression of LIN28B enhanced cellular migration, and invasion, and inhibited apoptosis. LIN28B may inhibit apoptosis by promoting Akt phosphorylation and by inhibiting Bad phosphorylation and Bcl-2 expression. In addition, LIN28B inhibited cell fusion and reduced cellular syncytia. CONCLUSIONS: LIN28B can inhibit cell invasion and migration in vitro and promote apoptosis and fusion. The low expression of LIN28B in URSA villous trophoblast cells may be one of the causes of abortion. The role of LIN28B in villous trophoblasts needs further study. LAY SUMMARY: Propagation of offspring is of great significance to the continuation of the human race. However, continuous pregnancy is more difficult for some women, especially women who have multiple miscarriages. One important contributor is the cessation of development caused by genetic factors of the embryo, but there are still many unknown reasons. We investigated the LIN28B gene which is a possible pathogenic factor in the placenta. We collected 25 cases of abortion in the experimental group (unexplained recurrent abortion group) and 25 in the control group (artificial termination of pregnancy group): on average at 7-8 weeks of pregnancy. We tested the function of lin28b in these samples and verified its function in cell lines. LIN28B plays an important role in maintaining early pregnancy by promoting the invasion of villous cells, inhibiting apoptosis and fusion, and the reduction of LIN28B expression may lead to the occurrence of early miscarriage.

Recent Advances in Pharmacological Intervention of Osteoarthritis: A Biological Aspect.

Osteoarthritis (OA) is a degenerative joint disease in the musculoskeletal system with a relatively high incidence and disability rate in the elderly. It is characterized by the degradation of articular cartilage, inflammation of the synovial membrane, and abnormal structure in the periarticular and subchondral bones. Although progress has been made in uncovering the molecular mechanism, the etiology of OA is still complicated and unclear. Nevertheless, there is no treatment method that can effectively prevent or reverse the deterioration of cartilage and bone structure. In recent years, in the field of pharmacology, research focus has shifted to disease prevention and early treatment rather than disease modification in OA. Biologic agents become more and more attractive as their direct or indirect intervention effects on the initiation or development of OA. In this review, we will discuss a wide spectrum of biologic agents ranging from DNA, noncoding RNA, exosome, platelet-rich plasma (PRP), to protein. We searched for key words such as OA, DNA, gene, RNA, exosome, PRP, protein, and so on. From the pharmacological aspect, stem cell therapy is a very special technique, which is not included in this review. The literatures ranging from January 2016 to August 2021 were included and summarized. In this review, we aim to help readers have a complete and precise understanding of the current pharmacological research progress in the intervention of OA from the biological aspect and provide an indication for the future translational studies.

Nuclear factor erythroid-2 related factor 2 inhibits human disc nucleus pulpous cells apoptosis induced by excessive hydrogen peroxide.

OBJECTIVE Nuclear factor erythroid-2 related factor 2 (Nrf2)/ antioxidant response element (ARE) is a novel defensive pathway involved in the oxidative and chemical stress of cells. The aim of the study was to explore the role of Nrf2 on the apoptosis of human disc nucleus pulpous cells induced by hydrogen peroxide (H2O2). METHODS The degeneration model of human intervertebral disc nucleus pulpous cells was established. The expression of Nrf2 was interfered with using sulforaphane (SFN); for that end, three groups were established: a blank group (H2O2-/SFN-), control group (H2O2+/SFN-), and an experimental group (H2O2+/SFN+). CCK8, Hoechst 33258 living cell staining was used to detect reactive oxygen species (ROS) content. RESULTS The apoptotic rates of the three groups were [(0.40±0.46)%], [(25.98±11.28)%], and [(3.83±2.06)%, respectively. The difference was statistically significant (p<0.05). The relative content of ROS in the three groups was [(100±7)%], [(1538±91)%], and [(818±63)%]; the difference was statistically significant (p<0.05). In Western blotting, Nrf2 content in the experimental group was higher than that in the control group. CONCLUSION Nrf2 exists in the nucleus pulpous cells of human intervertebral discs, which is related to the degeneration of the intervertebral disc. It has negative feedback regulation and can prevent the degeneration of the intervertebral disc by inhibiting the apoptosis of nucleus pulpous cells of human intervertebral discs caused by excessive ROS, which provides a new intervention strategy for the prevention and treatment of the degeneration of intervertebral discs.

Moderate-to-severe ovarian hyperstimulation syndrome: A retrospective multivariate logistic regression analysis in Chinese patients.

BACKGROUND: Ovarian hyperstimulation syndrome (OHSS), a life-threatening complication occurring in stimulated ovarian cycles, arises from treatment with gonadotropin for inducing follicular maturation. OBJECTIVES: The aim of this study was to compare the risk factors between patients with severe OHSS and those without OHSS after in vitro fertilization by intracytoplasmatic sperm injection/embryo transfer (IVF-ICSI/ET). Identifying the associated risk factors may provide guidance for clinicians on how to prevent OHSS. MATERIAL AND METHODS: The retrospective study involved patients who had completed IVF-ICSI/ET cycles. The difference in markers for predicting the occurrence of OHSS between groups was compared. The potential protective and risk factors, as well as the predictive markers, were identified. RESULTS: Patients with OHSS were younger (p = 0.015), had higher basal antral follicle counts (AFC) (p < 0.001) and lower total dosages of gonadotropin (Gn) (p = 0.011). On the day of human chorionic gonadotropin (hCG) administration, significantly higher total numbers of follicles (p < 0.001), serum estradiol (E2) (p < 0.001) and progestrone (Pg) (p = 0.001) levels, numbers of oocytes (p < 0.001) and metaphase II (MII) oocytes (p < 0.001) were also observed in the OHSS group when compared to the non-OHSS group. A univariate regression analysis revealed that age (OR = 0.898, 95% CI = 0.822-0.981) and total dosage of Gn (OR = 0.999, 95% CI = 0.999-1.000) were protective factors, whereas AFC (OR = 1.090, 95% CI = 1.051-1.131) and, on the day of hCG injection, the number of follicles (OR = 1.185, 95% CI = 1.027-1.230), serum E2 (OR = 1.000, 95% CI = 1.000-1.000) and Pg (OR = 2.773, 95% CI = 0.510-3.370) levels, the number of oocytes (OR = 1.254, 95% CI = 0.894-1.472) and MII oocytes (OR = 1.238, 95% CI = 0.747-1.217) were risk factors for OHSS. However, a multivariate regression analysis showed that the total number of follicles (OR = 1.124, 95% CI = 1.027-1.230) was the only predictive factor for the occurrence of OHSS. CONCLUSIONS: The study demonstrated that the follicle count measured on the day of hCG administration was the only predictive factor for the occurrence of OHSS. This provides basic guidance to clinicians on the prevention of the complication when using assisted reproductive technologies (ART).

Relationship between a low ratio of serum estradiol to follicle number and fertility treatment outcomes: A retrospective cohort study of 516 cases.

The aim of this retrospective study was to examine how a low estradiol/follicle (E2/fol) may be related to in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI)-embryo transfer outcomes in polycystic ovary syndrome (PCOS) and non-PCOS patients, respectively. Between 2013 and 2017, 516 IVF/ICSI cycles (146 cycles in PCOS patients and 370 cycles in non-PCOS patients) with a long gonadotrophin releasing hormone receptor agonist protocol-including 338 involved fresh transfer cycles (89 cycles in PCOS patients and 249 cycles in non-PCOS patients)-were conducted. Outcomes were compared between 5 groups of PCOS patients defined by E2/fol (pg/mL) as follows: A, <140; B, 140 to 210; C, 210 to 280; D, 280 to 350; and E, >350. Non-PCOS patients' outcomes are grouped as well. Whether in PCOS or non-PCOS patients, those in the lowest E2/fol group (<140 pg/mL) tended to be younger, and with a greater body mass index (BMI) and antral follicle count (AFC), than the patients in the other groups. Relative to the other groups, Group A showed a lower number and rate of oocytes, higher single pronucleus (1PN) and triple pronucleus (3PN) formation rate, early and advanced abortion rates, but these did not differ significantly from those of the other groups, it perhaps due to the limited sample size. Group A have a higher incidence of moderate or severe ovarian hyperstimulation syndrome than the other groups in non-PCOS patients (P > .05). Whether in PCOS or non-PCOS patients, greater BMI, greater AFC, and younger age may favor the phenomenon of low E2/fol. In turn, low E2/fol may reduce the oocyte retrieval rate and increase the risk of 1PN and 3PN formation and abortion.

Insulin Promotes the Proliferation of Human Umbilical Cord Matrix-Derived Mesenchymal Stem Cells by Activating the Akt-Cyclin D1 Axis.

Background. The functions of insulin in mesenchymal stem cells (MSC) remain poorly understood. Methods. MSC from human umbilical cord matrix (UCM) cultured in serum-free media (SFM) with or without insulin were subjected to various molecular biological analyses to determine their proliferation and growth states, expression levels of Akt-cyclin D1 signaling molecules, and in vitro differentiation capacities. Results. Insulin accelerated the G1-S cell cycle progression of UCM-MSC and significantly stimulated their proliferation and growth in SFM. The pro-proliferative action of insulin was associated with augmented cyclin D1 and phosphorylated Akt expression levels. Akt inactivation remarkably abrogated insulin-induced increases in cyclin D1 expression and cell proliferation, indicating that insulin enhances the proliferation of UCM-MSC via acceleration of the G1-S transition mediated by the Akt-cyclin D1 pathway. Additionally, the UCM-MSC propagated in SFM supplemented with insulin exhibited similar specific surface antigen profiles and differentiation capacities as those generated in conventional media containing fetal bovine serum. Conclusions. These findings suggest that insulin acts solely to promote UCM-MSC proliferation without affecting their immunophenotype and differentiation potentials and thus have important implications for utilizing insulin to expand clinical-grade MSC in vitro.

Toxoplasma gondii induces autophagy and apoptosis in human umbilical cord mesenchymal stem cells via downregulation of Mcl-1.

Autophagy and apoptosis are critical for controlling Toxoplasma gondii (T. gondii) infection. T. gondii infection during pregnancy can damage the fetus and cause birth defects; however, the molecular mechanisms of this process are poorly understood. This study aims to determine the activities of autophagy and apoptosis as well as their regulatory mechanisms during T. gondii infection by using human umbilical cord mesenchymal stem cells (hUC-MSCs) as a model of congenital diseases. LC3B, a hallmark protein of autophagy was incrementally upregulated with the infection duration, whereas p62 was downregulated in T. gondii-infected hUC-MSCs. Concurrent to this result, the invasion of T. gondii into hUC-MSCs increased in a time-dependent manner. The expression levels of Bcl-2 family proteins including Bcl-2, Bcl-xL, Bim, Bax, Bid and Bak were not altered; however, Mcl-1 levels in hUC-MSCs were dramatically decreased upon T. gondii infection. In addition, at 24 h post-infection, cleaved PARP and cleaved caspase-3 protein levels were elevated in hUC-MSCs. Importantly, Mcl-1 overexpression reduced the levels of autophagy- and apoptosis-related proteins in T. gondii-infected hUC-MSCs. Mcl-1 proteins were primarily expressed in the fraction containing mitochondria and strongly interacted with Beclin-1 under normal conditions; however, these interactions were remarkably attenuated by T. gondii infection. These results suggest that mitochondrial Mcl-1 is an essential signaling mediator regulating the activation of autophagy and apoptosis during T. gondii infection.

Effect of Mesenchymal Stem Cells and Platelet-Rich Plasma on the Bone Healing of Ovariectomized Rats.

We evaluated the efficacy of platelet-rich plasma (PRP) in combination with allogeneic bone marrow mesenchymal stem cells (BMSCs) for the treatment of osteoporotic bone defects in an ovariectomized rat model. By day 42 after injury, in vivo microcomputed tomography (micro-CT) imaging revealed that bone defects of control rats and ovariectomized rats treated with PRP and BMSCs were completely repaired, whereas those of ovariectomized rats treated with PRP or BMSCs alone exhibited slower healing. Histological data were consistent with these results. We also assessed changes to bone trabeculae in the proximal tibial growth plate. In ovariectomized rats treated with PRP or with a combination of PRP and BMSCs, the trabecular connectivity densities (Conn.D), bone volume ratios (BV/TV), and numbers (Tb.N) in the defect areas increased significantly from day 7 to day 42. These results indicate that PRP treatment enhances bone microarchitecture in osteoporosis. Moreover, expression levels of osteogenesis-specific marker genes including RUNX2, OSX, and OPN were significantly upregulated in rats treated with PRP and BMSCs compared to those of other groups. Thus, we conclude that treatment with PRP combined with BMSCs significantly promotes healing of osteoporotic bone defects. This study provides an alternative strategy for the treatment of osteoporotic bone loss.

Nuclear factor erythroid-2 related factor 2 inhibits human disc nucleus pulpous cells apoptosis induced by excessive hydrogen peroxide

SUMMARY OBJECTIVE Nuclear factor erythroid-2 related factor 2 (Nrf2)/ antioxidant response element (ARE) is a novel defensive pathway involved in the oxidative and chemical stress of cells. The aim of the study was to explore the role of Nrf2 on the apoptosis of human disc nucleus pulpous cells induced by hydrogen peroxide (H2O2). METHODS The degeneration model of human intervertebral disc nucleus pulpous cells was established. The expression of Nrf2 was interfered with using sulforaphane (SFN); for that end, three groups were established: a blank group (H2O2-/SFN-), control group (H2O2+/SFN-), and an experimental group (H2O2+/SFN+). CCK8, Hoechst 33258 living cell staining was used to detect reactive oxygen species (ROS) content. RESULTS The apoptotic rates of the three groups were [(0.40±0.46)%], [(25.98±11.28)%], and [(3.83±2.06)%, respectively. The difference was statistically significant (p<0.05). The relative content of ROS in the three groups was [(100±7)%], [(1538±91)%], and [(818±63)%]; the difference was statistically significant (p<0.05). In Western blotting, Nrf2 content in the experimental group was higher than that in the control group. CONCLUSION Nrf2 exists in the nucleus pulpous cells of human intervertebral discs, which is related to the degeneration of the intervertebral disc. It has negative feedback regulation and can prevent the degeneration of the intervertebral disc by inhibiting the apoptosis of nucleus pulpous cells of human intervertebral discs caused by excessive ROS, which provides a new intervention strategy for the prevention and treatment of the degeneration of intervertebral discs.

RESUMO OBJETIVO O fator 2 relacionado a NF-E2 (Nrf2)/elemento de resposta antioxidante (ARE) é uma nova via defensiva envolvida no estresse oxidativo e químico das células. O objetivo deste estudo foi explorar o papel do Nrf2 na apoptose das células do núcleo pulposo do disco humano induzida pelo peróxido de hidrogênio (H2O2). MÉTODOS O modelo de degeneração das células do núcleo pulposo do disco intervertebral humano foi estabelecido. A expressão do Nrf2 foi interferida utilizando-se sulforafano (SFN). Para isso foram estabelecidos três grupos: um grupo vazio (H2O2-/SFN-), um grupo de controle (H2O2+/SFN-), e um grupo experimental (H2O2+/SFN+). Utilizando CCK8 e Hoechst 33258, o conteúdo de espécies reativas de oxigênio (ERO) foi detectado. RESULTADOS As taxas de apoptose dos três grupos foram [(0,40 ± 0,46)%], [(25,98 ± 11,28%)] e [(3,83 ± 2,06)%], respectivamente. A diferença apresentou significância estatística (p < 0,05). O conteúdo relativo de ERO nos três grupos foi [(100±7)%], [(1538±91%)], e [(818±63%); a diferença foi estatisticamente significativa (p < 0,05). O método de Western blotting indicou um maior conteúdo de Nrf2 no grupo experimental do que no grupo de controle. CONCLUSÃO O Nrf2 existe em células do núcleo pulposo do disco intervertebral humano, que estão relacionadas à degeneração do disco intervertebral. Ele apresenta regulação por feedback negativo e pode evitar a degeneração do disco intervertebral inibindo a apoptose de células do núcleo pulposo do disco causada por excesso de ERO. Essa informação proporciona uma nova estratégia de intervenção para a prevenção e o tratamento da degeneração do disco intervertebral.

Sulforaphane reverses glucocorticoid-induced apoptosis in osteoblastic cells through regulation of the Nrf2 pathway.

Apoptosis of osteoblasts triggered by high-dose glucocorticoids (GCs) has been identified as a major cause of osteoporosis. However, the underlying molecular mechanisms accounting for this action remain elusive, which has impeded the prevention and cure of this side effect. Sulforaphane (SFP) is a naturally occurring isothiocyanate that has huge health benefits for humans. In this study, by using osteoblastic MC3T3-E1 cells as a model, we demonstrate the protective effects of SFP against dexamethasone (Dex)-induced apoptosis and elucidate the underlying molecular mechanisms. The results show that SFP could effectively inhibit the Dex-induced growth inhibition and release of lactate dehydrogenase in MC3T3-E1 cells. Treatment with Dex induced caspase-dependent apoptosis in MC3T3-E1 cells, as evidenced by an increase in the Sub-G1 phase, chromatin condensation, and deoxyribonucleic acid fragmentation, which were significantly suppressed by coincubation with SFP. Mitochondria-mediated apoptosis pathway contributed importantly to Dex-induced apoptosis, as revealed by the activation of caspase-3/-9 and subsequent cleavage of poly adenosine diphosphate ribose polymerase, which was also effectively blocked by SFP. Moreover, treatments of Dex strongly induced overproduction of reactive oxygen species and inhibited the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and the downstream effectors HO1 and NQO1. However, cotreatment with SFP effectively reversed this action of Dex. Furthermore, silencing of Nrf2 by small interfering ribonucleic acid significantly blocked the cytoprotective effects of SFP against Dex-induced apoptosis, which suggest the important role of Nrf2 signaling pathway and cell apoptosis induced by Dex. Taken together, this study provides a novel strategy for molecular intervention against Dex-induced osteoporosis using phytochemicals.

Expression of estrogen receptor α and ß in esophageal squamous cell carcinoma.

Estrogen receptors (ERs) are frequently expressed in human tumor tissues. There have been several studies concerning ER expression in esophageal cancers, yet the results are inconsistent, and the prognostic value of the receptors remains unclear. In the present study, we investigated the expression of ER protein and its correlation with clinical features of esophageal squamous cell carcinoma (ESCC) patients. Immunohistochemical staining for the ERs was carried out on paraffin-embedded primary tumor tissue sections from 89 patients with ESCC. Quantitative analyses were performed to determine the prognostic value of the expression of ERs, and Pearson's correlation was used to examine the relationship between ERα and ERß expression levels. Our results showed that ERα immunoreactivity was significantly lower in ESCC than that in the non-neoplastic epithelium (P=0.0445), whereas the ERß status was much stronger in ESCC than that in the non-neoplastic epithelium (P=0.0243). A significant inverse correlation was observed between ERα expression and depth of tumor invasion (P=0.0426). Correlation analysis revealed a statistically significant inverse correlation between the expression of ERα and ERß in ESCC (r=-0.2902, P=0.0058). Kaplan-Meier survival analysis showed that the patients with ERα expression (21/89) had a better outcome than patients without ERα expression (P=0.0280), whereas patients with high ERß immunoreactivity (44/89) were significantly associated with worse survival (P=0.0366). In conclusion, ERα and ERß levels were inversely correlated, and the downregulation of ERα and upregulation of ERß may indicate unfavorable prognosis of ESCC.