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To discover the promising antitumor agents, a series of β-carboline derivatives with nitrogen mustard moieties were designed and synthesized. Most target derivatives showed antiproliferative activity against MCF-7 and MDA-MB-231 cells. Among them, (1-methyl-9H-pyrido[3,4-b]indol-3-yl)methyl (S)-3-(4-(bis(2-chloroethyl)amino)phenyl)-2-formamidopropanoate possessed the most potent antiproliferative activity with IC50 values of 1.79 μM and 4.96 μM, respectively, which were significantly higher than that of the parent compounds, and the efficacy was comparable to that of the positive control doxorubicin. More importantly, it showed weak cytotoxicity against human normal breast cell line MCF-10A (IC50 > 20 μM), exhibiting certain selectivity. Subsequently, further mechanism exploration indicated that it induced G2/M phase cell cycle arrest and apoptosis in MDA-MB-231 cells. The DCFH-DA fluorescent probe assay and comet assay showed that this compound could cause intracellular ROS accumulation and DNA damage. In addition, it exerted potent inhibitory effect on the migration, invasion and adhesion of MDA-MB-231 cells in vitro. In short, (1-methyl-9H-pyrido[3,4-b]indol-3-yl)methyl (S)-3-(4-(bis(2-chloroethyl)amino)phenyl)-2-formamidopropanoate was considered as a promising compound for anti-breast cancer.

In this study, we combined two enemin-type diterpenoid derivatives with two well-established hydrogen sulfide moieties via ester or different anhydride linkers, to search apoptosis inducing drug candidate capable of hydrogen sulfide generating. Therefore, a series of hybrids were synthesized and superior antiproliferative efficacy accompanied with enhanced selectivity was observed under extensive pharmacological evaluations. A standard methylene blue (MB+) method was applied to measure the capacity for the hydrogen sulfide generation of all the target derivatives. One particular molecule A1, which contained α-thioctic acid moiety for hydrogen sulfide donating, manifested more potent antiproliferative activity. It exerted inhibitory effects against Bel-7402, SGC-7901 and A549 cell lines with IC50 values of 2.16, 5.07 and 6.98 μM respectively. While it exacted relatively low effects over human normal cell lines L-02 and PBMC with IC50 values of 15.81 μM for the prior and 14.15 μM for the latter, and displayed better selectivity index (SI) than parent diterpenoids. A high dosage of H2S release was also recorded. Hence, A1 was most suitable for mechanistic exploration on account of both safety and efficacy. The ensuing biological assays revealed central role of apoptosis in A1’s mode of action for antiproliferative efficacy, which led to further confirmation of G1 phase cell cycle arrest, mitochondria membrane potential collapse and apoptotic activation in Bel-7402 cells. Further western blot assay on intrinsic mitochondria pathway unlocked intricate interplay among a series of apoptotic related proteins in which Bax, caspase-3 and cytochrome c went through up-regulation, while Bcl-2, Bcl-xL and procaspase-3 undergone down-regulation. In a nutshell, a hydrogen sulfide releasing hybrid A1 was synthesized and antiproliferative evaluation identified it to be a worthy drug candidate for future in depth study.

The cytotoxicity properties of the β-carboline alkaloids have been broadly investigated. However, the potential application of β-carbolines was hindered due to the moderate activity in cancer. In the present study, thirty β-carboline-(phenylsulfonyl)furoxan hybrids (11a–j, 12a–j and 13a–j) were designed and synthesized through esterification and amidation reaction strategy, and their inhibitory activities against the human breast cancer cell lines MCF-7 and MDA-MB-231 were evaluated by CCK-8 assay. Biological evaluation presented that the most promising amide derivative 13h, substituted with p-methoxyphenyl group at position 1, generated high concentration of NO and evidently depressed the MCF-7 (IC50 = 0.89 μM) and MDA-MB-231 (IC50 = 0.62 μM) cells proliferation. Particularly, the wound healing and transwell assays demonstrated that 13h significantly inhibited the migration and invasion of MDA-MB-231cells. Furthermore, the preliminary mechanisms studies indicated that 13h induced G2/M phase arrest and apoptosis possibly causing by ROS accumulation and ROS-mediated DNA damage. Based on these considerations, 13h may be a promising antimetastatic agent for breast cancer, which is noteworthy for further exploration.

Oligodendrocytes are vulnerable to genetic and environmental insults and its injury leads to demyelinating diseases. The roles of ErbB receptors in maintaining the CNS myelin integrity are largely unknown. Here, we overactivate ErbB receptors that mediate signaling of either neuregulin (NRG) or epidermal growth factor (EGF) family growth factors and found their synergistic activation caused deleterious outcomes in white matter. Sustained ErbB activation induced by the tetracycline-dependent mouse toolPlp-tTA resulted in demyelination, axonal degeneration, oligodendrocyte precursor cell (OPC) proliferation, astrogliosis, and microgliosis in white matter. Moreover, there was hypermyelination before these inflammatory pathologic events. In contrast, sustained ErbB activation induced by another tetracycline-dependent mouse toolSox10+/rtTAcaused hypomyelination in the corpus callosum and optic nerve, which appeared to be a developmental deficit and did not associate with OPC regeneration, astrogliosis, or microgliosis. By tracing the differentiation states of cells expressing tetracycline-controlled transcriptional activator (tTA)/reverse tTA (rtTA)-dependent transgene or pulse-labeled reporter proteinsin vitroandin vivo, we found thatPlp-tTA targeted mainly mature oligodendrocytes (MOs), whereasSox10+/rtTAtargeted OPCs and newly-formed oligodendrocytes (NFOs). The distinct phenotypes of mice with ErbB overactivation induced byPlp-tTA andSox10+/rtTAconsolidated their nonoverlapping targeting preferences in the oligodendrocyte lineage, and enabled us to demonstrate that ErbB overactivation in MOs induced necroptosis that caused inflammatory demyelination, whereas in OPCs induced apoptosis that caused noninflammatory hypomyelination. Early interference with aberrant ErbB activation ceased oligodendrocyte deaths and restored myelin development in both mice. This study suggests that aberrant ErbB activation is an upstream pathogenetic mechanism of demyelinating diseases, providing a potential therapeutic target.SIGNIFICANCE STATEMENTPrimary oligodendropathy is one of the etiologic mechanisms for multiple sclerosis, and oligodendrocyte necroptosis is a pathologic hallmark in the disease. Moreover, the demyelinating disease is now a broad concept that embraces schizophrenia, in which white matter lesions are an emerging feature. ErbB overactivation has been implicated in schizophrenia by genetic analysis and postmortem studies. This study suggests the etiologic implications of ErbB overactivation in myelin pathogenesis and elucidates the pathogenetic mechanisms.

White matter abnormalities are an emerging pathological feature of schizophrenia. However, their attributions to the disease remain largely elusive. ErbB receptors and their ligands, some of which are essential for peripheral myelination, confer susceptibility to schizophrenia. By synergistically manipulating ErbB receptor activities in a oligodendrocyte-stage-specific manner in mice after early development, we demonstrate the distinct effects of ErbB signaling on oligodendrocytes at various differentiation states. ErbB overactivation, in mature oligodendrocytes, induces necroptosis causing demyelination, whereas in oligodendrocyte precursor cells, induces apoptosis causing hypomyelination. In contrast, ErbB inhibition increases oligodendrocyte precursor cell proliferation but induces hypomyelination by suppressing the myelinating capabilities of newly-formed oligodendrocytes. Remarkably, ErbB inhibition in mature oligodendrocytes diminishes axonal conduction under energy stress and impairs working memory capacity independently of myelin pathology. This study reveals the etiological implications of oligodendrocyte vulnerability induced by ErbB dysregulation, and elucidates the pathogenetic mechanisms for variable structural and functional white matter abnormalities.

As one of the most lethal diseases, pancreatic cancer shows a dismal overall prognosis and high resistance to most treatment modalities. Furthermore, pancreatic cancer escapes early detection during the curable period because early symptoms rarely emerge and specific markers for this disease have not been found. Although combinations of new drugs, multimodal therapies, and adjuvants prolong survival, most patients still relapse after surgery and eventually die. Consequently, the search for more effective treatments for pancreatic cancer is highly relevant and justified. As a newly re-discovered mediator of gasotransmission, hydrogen sulfide (H2S) undertakes essential functions, encompassing various signaling complexes that occupy key processes in human biology. Accumulating evidence indicates that H2S exhibits bimodal modulation of cancer development. Thus, endogenous or low levels of exogenous H2S are thought to promote cancer, whereas high doses of exogenous H2S suppress tumor proliferation. Similarly, inhibition of endogenous H2S production also suppresses tumor proliferation. Accordingly, H2S biosynthesis inhibitors and H2S supplementation (H2S donors) are two distinct strategies for the treatment of cancer. Unfortunately, modulation of endogenous H2S on pancreatic cancer has not been studied so far. However, H2S donors and their derivatives have been extensively studied as potential therapeutic agents for pancreatic cancer therapy by inhibiting cell proliferation, inducing apoptosis, arresting cell cycle, and suppressing invasion and migration through exploiting multiple signaling pathways. As far as we know, there is no review of the effects of H2S donors on pancreatic cancer. Based on these concerns, the therapeutic effects of some H2S donors and NO–H2S dual donors on pancreatic cancer were summarized in this paper. Exogenous H2S donors may be promising compounds for pancreatic cancer treatment., Graphical abstract The review summarizes the antitumor mechanisms of H2S donating derivatives against pancreatic cancer by modulating signaling pathways, including PI3K/AKT/mTOR, SHH, NF-κB, MAPK, NOTCH, STAT3, DR4, etc. Perspectives on future directions and challenges are also discussed.Image 1

Diterpenoids are important and widely distributed natural compounds with various biological effects, including antitumor, anti-inflammatory and so on. Great efforts have been put in phytochemistry research on diterpenoids. A number of structural modified derivatives and pharmacophore incorporated hybrids were also designed and synthesized with promising therapeutic effects. Among the hopefuls, enmein-type 6,7-seco-ent-kaurane diterpenoids with unique ring system and stereogenic centers exhibit attractive activities. Based on their lead-like properties, enmein-type diterpenoids are suitable for further medicinal study. The derivatives were biologically evaluated and showed promising activities, which warranted in-depth research for further understanding. In this review, the natural bioactive enmein-type diterpenoids and the synthetic derivatives were comprehensively summarized.

A series of novel nitrogen mustard-evodiamine hybrids were synthesized and evaluated for their antitproliferative properties. The antiproliferative activities of 10a-d, 11a-d, and 12a-d against four different kinds of human cancer cell lines (PC-3, HepG2, THP-1 and HL-60) and human normal peripheral blood mononuclear cells (PBMC) were determined. The results showed that all the target hybrid compounds exhibited antiproliferative activities against tested human tumor cell lines to some extent and no antiproliferative activities (>200 μM) against human normal PBMC cells. The antiproliferative selectivity between tumorous and normal cells was very useful for further antitumor drug development. Among the target compounds, 12c showed the strongest cytotoxicity against two tumor cell lines (THP-1 and HL-60) with IC50 values of 4.05 μM and 0.50 μM, respectively, and selected for further mechanism study in HL-60 cells. The results showed that 12c could induce HL-60 cells apoptosis and arrest at G2 phase at low sub-micromolar concentrations via mitochondria-related pathways.

In the present study, the hypoglycemic effect of silychristin A on streptozotocin (STZ)-induced type 1 diabetes in rats was evaluated and the underlying pharmacological mechanism was further elucidated in vitro. Silychristin A significantly lowered the glucose level, increased insulin secretion, and improved the structure of β cells in STZ-induced rats. Accordantly, reactive oxygen species (ROS) production induced by STZ or high concentration of glucose (HG) was effectively suppressed by silychristin A in pancreatic INS-1 β cells evaluated by flow cytometry. Western blot analysis demonstrated that silychristin A markedly suppressed STZ or HG induced cell apoptosis. In addition, in vitro inhibitory effect of silychristin A on α-glucosidase and molecular docking analysis revealed that silychristin A could reduce the digestion rate of carbohydrates. These findings indicate that silychristin A may be useful as a potential functional food ingredient against oxidative stress-mediated destruction of pancreatic islet β cells and inhibition of α-glucosidase activity.

The aim of the present study was to assess the therapeutic effects of atorvastatin on cerebral vessel autoregulation and to explore the underlying mechanisms in a rabbit model of subarachnoid hemorrhage (SAH). A total of 48 healthy male New Zealand rabbits (weight, 2‑2.5 kg) were randomly allocated into SAH, Sham or SAH + atorvastatin groups (n=16/group). The Sham group received 20 mg/kg/d saline solution, whereas 20 mg/kg/d atorvastatin was administered to rabbits in the SAH + atorvastatin group following SAH induction. Changes in diameter, perimeter and basilar artery (BA) area were assessed and expression levels of the vasoactive molecules endothelin‑1 (ET‑1), von Willebrand factor (vWF) and thrombomodulin (TM) were measured. Neuronal apoptosis was analyzed 72 h following SAH by terminal deoxynucleotidyl-transferase‑mediated dUTP nick‑end labeling (TUNEL) staining. The mortality rate in the SAH group was 18.75, 25% in the SAH + atorvastatin treated group and 0% in the Sham group (n=16/group). The neurological score in the SAH + atorvastatin group was 1.75±0.68, which was significantly higher compared with the Sham group (0.38±0.49; P

A series of enmein-type diterpenoid amino acid ester derivatives (14–22) were designed and synthesized according to l -alanine-(14-oridonin) ester trifluoroacetate (clinical candidate HAO472). Their antiproliferative activities were tested against SGC-7901, Bel-7402, HL-60, PC-3, A549 and K562 cancer cell lines and L-02 normal liver cells. The results showed that compound 19 possessed the most potent cytotoxicity with IC50 s at sub-micromolar level against human hepatoma Bel-7402 and chronic myelogenous leukemia K562 cells and more potent than l -alanine-(14-oridonin) ester (23). More importantly, 19 displayed 70-fold less cytotoxicity than parent 3 (IC50 = 25.47 μM) against L-02 cells, which exhibited certain selectivity. Further mechanism study in Bel-7402 cells revealed that 19 could induce apoptosis, G1 phase cell cycle arrest and mitochondrial dysfunction. Western blot results of caspase-3, Bax and cytochrome c upregulation and pro-caspase-3, Bcl-2 and Bcl-xL downregulation confirmed the intrinsic pathways. Overall, these data collectively demonstrated the high efficiency and selectivity of 19, l -phenylalanine-enmein-type diterpenoid ester, which inspires further and effective application as a potential antitumor candidate.

Herein, we reported the cytotoxicity, NO-releasing property, and apoptosis induced ability of two series of novel nitric oxide-releasing spirolactone-type diterpenoid derivatives (10a–f and 15a–f). All the title compounds were more potent than oridonin (7) and parent compound (9 or 14) against human tumor Bel-7402, K562, MGC-803 and CaEs-17 cells. SARs were concluded based on above data. Compound 15d exhibited the strongest antiproliferative activity with the IC50 of 0.86, 1.74, 1.16 and 3.75 μM, respectively, and could produce high level (above 25 μM) of NO at the time point of 60 min. Further mechanism evaluation showed that 15d could induce S phase cell cycle arrest and apoptosis at low micromolar concentrations in Bel-7402 cells via mitochondria-related pathways. It was expected that the remarkable biological profile of the synthetic NO-releasing spirolactone-type diterpenoid analogs make them possible as promising candidates for the development of anticancer agents.

To get chelidonine derivatives with enhanced antiproliferative activity and selectivity, a series of nitric oxide donating derivatives (10a-f and 11a-j) were designed, synthesized and biologically evaluated. Compared with chelidonine, these compounds exhibited lower IC50 values against human hepatoma cells HepG2, breast cancer cells MCF-7, colon cancer cells HCT-116, as well as leukemia cells K562. Compound 11j displayed the strongest antiproliferative activity with IC50 values of 3.91, 6.90, 4.36 and 1.12 μM against the above four cells, respectively. Nevertheless, it showed an IC50 value >40 μM against human peripheral blood mononuclear cells (PBMCs), which demonstrated high selectivity between normal and cancer blood cells. In further mechanism studies, 11j showed the capability to induce K562 cells apoptosis, S phase cell cycle arrest and mitochondrial membrane potential disorder. Besides, 11j was found to be effective in promoting the expression of proapoptotic protein Bad and suppressing the expression of anti-apoptotic proteins Bcl-xL, catalase, survivin, claspin and clusterin.

To explore antitumor agents with high efficiency and selectivity, two series of 16 H2S donating evodiamine derivatives 8-12 were synthesized and characterized by 1H NMR, 13C NMR and HRMS. Their antiproliferative activities were tested against five cancer cell lines (Bel-7402, MCF-7, SGC-7901, Caco-2 and HL-60) and human normal peripheral blood mononuclear cells. Among them, compound 12c showed the most potent inhibitory activities against human leukemia HL-60 and epithelial colorectal adenocarcinoma Caco-2 cells with IC50 values of 0.58 and 2.02 μM, respectively. Additionally, high selectivity was also observed between human normal peripheral blood mononuclear cells and human leukemia HL-60 cells. Further mechanism studies confirmed that 12c could induce apoptosis, arrest cell cycle at the G2/M phase and lead to mitochondrial dysfunction in HL-60 cells. Furthermore, western blot assay demonstrated that 12c induced the intrinsic apoptotic mitochondrial pathway by upregulating protein expression of Bax, cytochrome c, caspase-3, -9 and p53, and downregulating the relative levels of Bcl-2. The levels of cell cycle related proteins cyclin B1 and cdc2 were also downregulated in which G2/M phase arrest was confirmed. Overall, 12c possessed immense potential for the discovery of antitumor candidates with high efficiency and selectivity.

Background Recently, we devoted to disclosing the antibacterial activities of enmein-type 6,7-seco-ent-kauranoid derivatives. Objective Eleven new enmein-type diterpenoid derivatives with different substituents and drug-like properties were designed and synthesized. Method The antimicrobial activities against E. coli, S. aureus, B. subtilis and M. albicans were disclosed. The antiproliferative activities against human cancer Bel-7402, K562, MGC-803 and CaEs-17 cells and non-cancerous L-02 cells were also measured by MTT method. Results The results revealed that enmein-type diterpenoids showed more promising activities against tested gram-positive bacteria than gram-negative bacterium and fungus. Compound 9 with R of 2-quinolyl group exhibited the strongest antimicrobial activities with MIC values of 7.81 µg/ml and 0.98 µg/ml against S. aureus and B. subtilis, respectively. All the target derivatives exhibited superior cytotoxic activities to compounds 1 and 2 against tumor cells, and slight selectivity between cancerous cells and normal liver cells. Compound 12 with R of 3-(2-chloropyridyl) group and IC50 values of 0.7 µM, 0.9 µM, 0.8 µM and 2.0 µM agaist four tumor cells, respectively, was selected for further mechanism study in Bel-7402 cell line. Conclusion Compound 12 could induce S phase cell cycle arrest and apoptosis at low concentrations via mitochondria-related pathways. The effects of compound 12 on some apoptosis related proteins showed that CDK2 was up regulated and ATM and cyclin A1 were down-regulated which confirmed the apoptosis and cell cycle effects.

Rhizoma Dioscoreae polysaccharides (RDPS) are the primary active ingredient of Rhizoma Dioscoreae, which is a traditional Chinese medicine. RDPS have previously been shown to scavenge reactive oxygen species, and protect against D-galactose-induced mimetic aging. The present study aimed to investigate the neuroprotective effects of RDPS against hypoxia-induced neuronal cell apoptosis. Neuronal cells harvested from pregnant Sprague-Dawley rats were divided into groups, as follows: i) Normal control group; ii) hypoxia-induced apoptosis neuronal cell model; iii) 0.025 g/l RDPS-treated group; iv) 0.05 g/l RDPS-treated group; v) 0.1 g/l RDPS-treated group; and vi) 0.25 g/l RDPS treated group. Neuronal cell viability was investigated using an MTT assay, and neuronal cell apoptosis was analyzed using Annexin V-fluorescein isothiocyanate/propidium iodide double-staining, Hoechst 33342 fluorescent staining, Rhodamine 123 staining, polymerase chain reaction and immunocytochemical staining. The RDPS-treated neuronal cells exhibited improved viability, and decreased hypoxia-induced mitochondrial injury and apoptosis. In addition, the mRNA and protein expression levels of caspase-3 and B-cell lymphoma (Bcl)-2-associated X protein (Bax) were significantly downregulated, whereas the mRNA and protein expression levels of Bcl-2 were significantly upregulated, in the RDPS-treated hypoxic neurons, as compared with the apoptosis model (P

Herein, we reported on a series of synthetic nitric oxide-releasing enmein-type diterpenoid hybrids (9a–i). All the target compounds showed potent antibacterial activity against selected Gram-positive bacteria S. aureus and B. subtilis. The antiproliferative activity against human tumor K562, MGC-803, CaEs-17 and Bel-7402 cells, and human normal liver cells L-02 was tested and the structure activity relationships (SARs) were also concluded. Compounds 9b and 9d showed the best activity against S. aureus and B. subtilis with the same minimal inhibitory concentrations (MICs) of 4 and 2 μg/mL, respectively. The derivative 9f displayed IC50 values of 1.68, 1.11, 3.60 and 0.72 μM against the four cancer cell lines above and 18.80 μM against normal liver cells L-02; meanwhile, 9f also released a high level of NO at the time point of 60 min of 22.24 μmol/L. Furthermore, it was also found that 9f induced apoptosis via the mitochondria-related pathway and arrested cell cycle of Bel-7402 cells at S phase. These findings might be important to explore new chemical entities for the main causes of in-hospital mortality of S. aureus infection, combined with a solid tumor.

Isodon rubescens has been used as a traditional green tea for more than 1000 years and many medicinal functions of I. rubescens are also very useful, such as its well-known antitumor and antibacterial activities. Oridonin, a bioactive ent-kaurane diterpenoid, is the major ingredient of this medicinal tea. Herein, 22 novel oridonin derivatives were designed and synthesized. The antibacterial activity was evaluated for the first time. Compound 12 was the most promising one with MIC of 2.0 μg/mL against B. subtilis, which was nearly 3-fold stronger than positive control chloromycetin. The antiproliferative property was also assayed and compound 19 showed stronger activity than taxol. The apoptosis-inducing ability, cell cycle arrest effect at S phase and influence of mitochondrial membrane potential by 19 in CaEs-17 cancer cells were first disclosed. Based on the above results, the cell apoptosis induced by compound 19 in CaEs-17 cells was most probably involved in the intrinsic apoptotic pathway.

The first series of nitric oxide donating derivatives of evodiamine were designed and prepared. NO releasing ability of all target derivatives was evaluated in BGC-823, Bel-7402 and L-02 cells. The cytotoxicity was evaluated against three human tumor cell lines (Bel-7402, A549 and BGC-823) and normal human liver cells L-02. The nitrate derivatives 11a and 11b only exhibited moderate activity and furoxan-based derivatives 13a-c, 14a and 14b showed promising activity. 13c showed good cytotoxic selectivity between tumor and normal liver cells and was further investigated for its apoptotic properties on human hepatocarcinoma Bel-7402 cells. The molecular mode of action revealed that 13c caused cell-cycle arrest at S phase and induced apoptosis in Bel-7402 cells through mitochondria-related caspase-dependent pathways.

The goal of this study was to determine whether tetrandrine enhanced radiosensitization in different hepatocellular carcinoma cell lines and to elucidate the potential mechanism. We also tested whether PA28γ was regulated by tetrandrine. The human hepatocellular carcinoma cell lines HepG2 and LM3 were divided into six groups: control; low-dosage (0.5 or 5 μg/ml) tetrandrine alone; high-dosage (1.0 or 10 μg/ml) tetrandrine alone; irradiation alone; irradiation with low-dosage (0.5 μg/ml or 5 μg/ml) tetrandrine; and irradiation with high-dosage (1.0 μg/ml or 10 μg/ml) tetrandrine. Colony-forming assays were performed. Expression of cyclin and apoptosis-related proteins, including cyclin B1, phosphorylated cyclin-dependent kinase 1 [phospho-CDC2 (Tyr15)], Bax and caspase-3, as well as PA28γ expression, were evaluated using Western blot analysis. Apoptosis rate and cell cycle distribution were examined using flow cytometry analysis. Tetrandrine enhanced radiosensitivity in HepG2 and LM3 cells, as characterized by a narrower shoulder area and steeper linear area, and the enhanced radiosensitization increased with tetrandrine dosage. After tetrandrine treatment, the apoptosis rate significantly increased, whereas the proportion of cells in the G2 phase dramatically decreased in dose- and time-dependent manners after irradiation. However, the effect of reverse G2 arrest was weaker in p53-mutant cells (LM3 cells). Finally, we observed that tetrandrine downregulated PA28γ expression. Moreover, when PA28γ was downregulated, apoptosis and cell cycle distribution were also altered; however, the effects were weaker in p53-mutant cells. Therefore, we propose that tetrandrine-mediated apoptosis induction and G2 arrest attenuation are at least partly mediated by PA28γ.

Radiation-induced liver injury remains a clinical problem and data suggest that sinusoidal endothelial cells (SECs) are an important target. The purpose of this study was to determine whether the inhibition of Kupffer cells before exposure would protect SECs from radiation-induced injury. Sprague-Dawley rats were intravenously injected 24 h before irradiation with Kupffer cell inhibitor gadolinium chloride (GdCl3) (10 mg/kg body weight). Three groups of animals were treated: 1. control group (saline and sham irradiation); 2. GdCl3 + 30 Gy radiation group and 3. 30 Gy radiation only group. Specimens were collected at 2, 6, 12, 24 and 48 h after completion of each treatment. Liver tissue was assessed for inflammatory cytokine expression and radiation-induced SEC injury based on serum hyaluronic acid (HA) level, apoptosis and ultrastructural and histological analyses. The results showed that radiation exposure caused apoptosis of SECs, but not hepatocytes. Inflammatory cytokine expression, including tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) expression, was significantly attenuated in the GdCl3 + 30 Gy radiation group, compared with the 30 Gy radiation-only group (P0.05). The GdCl3 + radiation-treated rats exhibited significantly lower levels of HA and SEC apoptosis than the radiation-treated only rats at early time points, and radiation-induced liver injury was also attenuated. In conclusion, we hypothesize that selective Kupffer cell inhibition by gadolinium chloride was shown to reduce apoptosis in SECs caused by irradiation of the live and protected the liver against radiation-induced injury.

Heavy metals, such as lead (Pb2+), are usually accumulated in human bodies and impair human's health. Lead is a metal with many recognized adverse health side effects and yet the molecular processes underlying lead toxicity are still poorly understood. In the present study, we proposed to investigate the effects of lead toxicity in cultured cardiofibroblasts. After lead treatment, cultured cardiofibroblasts showed severe endoplasmic reticulum (ER) stress. However, the lead-treated cardiofibroblasts were not dramatically apoptotic. Further, we found that these cells determined to undergo autophagy through inhibiting mammalian target of rapamycin complex 1 (mTORC1) pathway. Moreover, inhibition of autophagy by 3-methyladenine (3-MA) may dramatically enhance lead toxicity in cardiofibroblasts and cause cell death. Our data establish that lead toxicity induces cell stress in cardiofibroblasts and protective autophagy is activated by inhibition of mTORC1 pathway. These findings describe a mechanism by which lead toxicity may promote the autophagy of cardiofibroblasts cells, which protects cells from cell stress. Our findings provide evidence that autophagy may help cells to survive under ER stress conditions in cardiofibroblasts and may set up an effective therapeutic strategy for heavy metal toxicity., Lead is a metal with many recognized adverse health side effects, and yet the molecular processes in cardiofibroblasts underlying lead toxicity are still poorly understood. Our current findings will help to understand the role of lead-mediated toxicity in cardiofibroblasts, indicating that autophagy serves a protective role in response to ER stress, which affords to set up an effective therapeutic strategy for the numerous diseases related to lead-toxicity.

Kupffer cells play an important role in keeping liver from occurrence of tumors. Apoptosis is thought to be a major mechanism responsible for the anti-tumor function of Kupffer cells. Previous studies have mainly concentrated on the direct contact and interaction between Kupffer cells and tumor cells. The present experiment is to investigate the apoptotic pathway in tumor induced by culture supernatant from activated Kupffer cells. The levels of Bax, Bcl-2 and iNOS were analyzed in an in vivo mouse tumor model, which was treated with culture supernatant from activated Kupffer cells. The results showed that the expression of Bax significantly increased while the expression of Bcl-2 decreased when tumor cells were treated with culture supernatants from activated Kupffer cells. The alteration of Bax and Bcl-2 levels resulted in an increase in the ratio of Bax to Bcl-2, which had negative correlation with the size of tumor and positive correlation with the expression of iNOS. The expression of TNFα and the occurrence of apoptosis were also increased in tumor treated with culture supernatants from activated Kupffer cells, compared with those which received no treatment. In conclusion, culture supernatants from activated Kupffer cells were able to change the balance between Bax and Bcl-2 in favor of the former. The ratio of Bax to Bcl-2 is a useful index to evaluate tumor apoptosis induced by Kupffer cells. Our experiment also suggests that alteration of the ratio of Bax to Bcl-2 may result from increased levels of iNOS and TNFα.

Herein, two careful selected anticancer drugs camptothecin (CPT) and cytarabine (Ara-C) with different biological action mechanisms and different water solubility are conjugated together through a glutathione (GSH) cleavable disulfide bond to construct a redox-sensitive drug-drug conjugate, which can self-assemble into nanoparticles, thus notably improving the water solubility of CPT and the cell membrane permeability of Ara-C. Compared with free drugs, the self-assembled CPT-ss-Ara nanoparticles can concentrate in tumor tissues through the enhanced permeability and retention (EPR) effect, then they can be rapidly internalized by tumor cells and degrade into free drugs for killing the tumor cells when exposed to the reductive environment (GSH) of tumor cells, thereby reducing the injury to normal cells. Meanwhile, the CPT-ss-Ara nanoparticles can effectively protect CPT and Ara-C molecules from biological inactivation before their arrival in tumor microenvironment since free CPT and Ara-C are easy to partly lose their therapy efficacy due to their structure degradation in blood circulation. The in vitro and in vivo anticancer experimental results indicate that simultaneous release of free CPT and Ara-C can realize synergistic chemotherapy effects, thus markedly improve their anticancer activity. Therefore, our designed carrier-free, redox-sensitive CPT-ss-Ara nanoparticles might have promising clinical application to combat cancers.

Rhizoma Atractylodis macrocephalae have an important role in treating cerebrovascular diseases in Traditional Chinese Medicine (TCM). The purpose of the present study was to determine the neuroprotective effect of Atractylodis macrocephalaon polysaccharides (AMPS) on hypoxia-induced apoptosis of cerebral cortical neurons. Neuronal cells obtained from neonatal rats were divided into the following groups: Normal control (group C); apoptosis positive induced by hypoxia-reoxygenation culture of rat primary cerebral cortical neurons (group A); treated with 0.025 g/l AMPS prior to hypoxia culture of neurons (AMPS1); treated with 0.05 g/l AMPS (AMPS2); treated with 0.1 g/l AMPS (AMPS3); and treated with 0.25 g/l AMPS (AMPS4). Neuronal apoptosis was examined with Annexin V-fluorescein isothiocyanate/propidium iodide, Hoechst 33342 fluorescent staining, Rhodamine 123 staining, polymerase chain reaction assay and immunocytochemical staining. The results showed that the AMPS significantly prevented the growth inhibition, mitochondrial injury and apoptosis of neurons induced by hypoxia. The levels of Caspase-3 and Bax mRNAs and proteins were significantly downregulated by AMPS in neurons exposed to hypoxia, and the levels of B-cell lymphoma 2 (Bcl-2) protein was significantly upregulated by AMPS in neurons exposed to hypoxia, as compared with group A (P

Kupffer cells play an important role in keeping liver from occurrence of tumors. Apoptosis is thought to be a major mechanism responsible for the anti-tumor function of Kupffer cells. Previous studies have mainly concentrated on the direct contact and interaction between Kupffer cells and tumor cells. The present experiment is to investigate the apoptotic pathway in tumor induced by culture supernatant from activated Kupffer cells. The levels of Bax, Bcl-2 and iNOS were analyzed in an in vivo mouse tumor model, which was treated with culture supernatant from activated Kupffer cells. The results showed that the expression of Bax significantly increased while the expression of Bcl-2 decreased when tumor cells were treated with culture supernatants from activated Kupffer cells. The alteration of Bax and Bcl-2 levels resulted in an increase in the ratio of Bax to Bcl-2, which had negative correlation with the size of tumor and positive correlation with the expression of iNOS. The expression of TNF alpha and the occurrence of apoptosis were also increased in tumor treated with culture supernatants from activated Kupffer cells, compared with those which received no treatment. In conclusion, culture supernatants from activated Kupffer cells were able to change the balance between Bax and Bcl-2 in favor of the former. The ratio of Bax to Bcl-2 is a useful index to evaluate tumor apoptosis induced by Kupffer cells. Our experiment also suggests that alteration of the ratio of Bax to Bcl-2 may result from increased levels of iNOS and TNF alpha.