Anticancer and antibacterial activity in vitro evaluation of iridium(III) polypyridyl complexes.

Three iridium(III) polypyridyl complexes [Ir(ppy)2(PYTA)](PF6) (1) (ppy = 2-phenylpyridine), [Ir(bzq)2(PYTA)](PF6) (2) (bzq = benzo[h]quinolone) and [Ir(piq)2(PYTA)](PF6) (3) (piq = 1-phenylisoquinoline, PYTA = 2,4-diamino-6-(2'-pyridyl)-1,3,5-triazine) were synthesized and characterized by elemental analysis, IR, 1H NMR and 13C NMR. The cytotoxic activity of the complexes toward cancer SGC-7901, Eca-109, A549, HeLa, HepG2, BEL-7402 and normal LO2 cell lines was investigated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Complex 3 shows the most effective on inhibiting the above cell growth among these complexes. The complexes locate at the lysosomes and mitochondria. AO/EB, Annex V and PI and comet assays indicate that the complexes can induce apoptosis in SGC-7901 cells. Intracellular ROS and mitochondrial membrane potential were examined under fluorescence microscopy. The results demonstrate that the complexes increase the intracellular ROS levels and induce a decrease in the mitochondrial membrane potential. The complexes can enhance intracellular Ca2+ concentration and cause a release of cytochrome c. The autophagy was studied using MDC staining and western blot. Complexes 1-3 can effectively inhibit the cell invasion with a concentration-dependent manner. Additionally, the complexes target tubules and inhibit the polymerization of tubules. The antimicrobial activity of the complexes against S. aureus, E. coli, Salmonella and L. monocytogenes was explored. The mechanism shows that the complexes induce apoptosis in SGC-7901 cells through ROS-mediated lysosomal-mitochondrial, targeting tubules and damage DNA pathways. Three iridium(III) complexes [Ir(N-C)2(PYTA)](PF6) (N-C = ppy, 1; bzq, 2; piq, 3) were synthesized and characterized. The anticancer activity of the complexes against SGC-7901 cells was studied by apoptosis, comet assay, autophagy, ROS, mitochondrial membrane potential, intracellular Ca2+ levels, release of cytochrome c, tubules and western blot analysis. The antibacterial activity in vitro was also assayed.

Novel ethanocycloheptono [3,4,5-kl]benzo[a]xanthene induces apoptosis in BEL-7402 cells.

A novel polycyclic bridged-ring xanthene 2 was synthesized by nucleophilic substitution followed by Michael addition reaction between parent dibenzoxanthene 1 and acetylacetone. The structure of compound 2 was also confirmed by single-crystal X-ray diffraction. We studied the binding activity of this compound with bovine serum albumin (BSA) by fluorescent and UV-visible spectra. The results showed that compound had strong binding ability with BSA. Cell viability in five tumor cell lines was studied by MTT assay. The cytotoxic effect of bridged-ring xanthene 2 against BEL-7402 cells was examined by morphological analyses and biochemical assays. Significant nuclear damages of BEL-7402 cells were observed after cells were treated with compound in a comet assay. The compound also caused DNA damage and S phase arrest in BEL-7402 cells. The efficient induction of apoptosis by the compound was confirmed by flow cytometry. Additionally, the characteristic nuclear and morphological changes during apoptotic cell death were investigated by fluorescent microscopy. The compound 2 enhanced the reactive oxygen species (ROS) and decreased the mitochondrial membrane potential. Western blot assay indicated that the compound can active caspase-3, caspase-7, down-regulate the level of Bcl-2, Bcl-x, and up-regulate the level of pro-apoptosis protein Bax. The compound 2 induces apoptosis of BEL-7402 cells through a ROS-mediated mitochondrial dysfunction pathway.

Synthesis of novel dibenzoxanthene derivatives and observation of apoptosis in human hepatocellular cancer cells.

We have synthesized dibenzoxanthene derivatives 2a-2i via nucleophilic substitution of methoxyl group and evaluated underlying antitumor molecular mechanism of target compounds. Compounds showed high cytotoxic activities against BEL-7402, A549, HeLa and MG-63 cancer cells in the µM range. These compounds inhibited the cell growth of BEL-7402 cells at S or G2/M phase. The compounds 2a-2i also induced the apoptosis of BEL-7402 cells. In addition, compounds enhanced the level of intramolecular ROS and decreased the mitochondrial membrane potential. Western blot analysis showed caspase-3 were activated and the expression of Bcl-2 and Bcl-xl was down-regulated. According to given results, these dibenzoxanthenes exhibited a broad spectrum of antiproliferative effects on various tumors and therapeutic efficacy. Molecular mechanism indicated that induction of apoptosis was associated with DNA fragmentation, ROS generation, mitochondria dysfunction. Compounds induced apoptosis in BEL-7402 cells through the intrinsic ROS-mediated mitochondrial pathway.

Synthesis, Molecular Structure, DNA/Protein Binding, Cytotoxicity, Apoptosis, Reactive Oxygen Species, and Mitochondrial Membrane Potential of Dibenzoxanthenes Derivatives.

Two dibenzoxanthene isomers 3 and 4 were synthesized and characterized. The crystal structures of the two compounds were solved by single-crystal X-ray diffraction. Binding of two compounds with calf thymus DNA (CT DNA) and BSA (bovine serum albumin) has been thoroughly investigated by UV-Vis and fluorescence spectroscopy. The DNA-binding constants were determined to be 2.51 (± 0.09) × 10(3) for compound 3 and 4.55 (± 0.10) × 10(3) for compound 4. Two compounds can cleave pBR322 DNA upon irradiation. Significant nuclear damages of BEL-7402 cells were observed with compound treatment in a comet assay. The cytotoxicity in vitro was investigated by MTT method. These compounds have been found to induce nuclear condensation and fragmentation in BEL-7402 cells. The two compounds can enhance intracellular reactive oxygen species and decrease the mitochondrial membrane potential. The compounds activated caspase-3 and caspase-7, down-regulated the expression levels of anti-apoptotic protein Bcl-2, and up-regulated the expression levels of pro-apoptotic protein Bax. These compounds induce apoptosis of BEL-7402 cells through an ROS-mediated mitochondrial dysfunction pathway.

Molecular cloning and characterization of NPR1 gene from Arachis hypogaea.

The NPR1 gene was an important regulator for a plant disease resistance. The cDNA of NPR1 gene was cloned from peanut cultivar Ri Hua 1 by rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR). The full length cDNA of Arachis hypogaea NPR1 consisted of 2,078 base pairs with a 1,446 bp open-reading frame encoding 481 amino acids. The predicted NPR1 contained the highly conserved functional domains (BTB/POZ domain from M1 to D116), protein-protein interaction domains (three ankyrin repeats from K158 to L186; N187 to L217 and R221 to D250) and one NPR1-like domain (C262 to S469). The DNA sequence of the NPR1 gene was 2,332 or 2,223 bp. Both two sequences contained three introns and four exons. The NPR1 transcripts were expressed mainly in roots and leaves, while fewer signals were detected in the stems. Amount of the NPR1 transcript was significantly increased 1 h after salicylic acid challenge and was eventually 5.3 times greater than that in the control group. Both the DNA sequence and the coding sequence were obtained from eight cultivars and nine wild species of Arachis. Maximum likelihood analyses of d N/d S ratios for 25 sequences from different species showed that different selection pressures may have acted on different branches.

Clinical value of precise rehabilitation nursing in management of cerebral infarction.

BACKGROUND: Cerebral infarction, previously referred to as cerebral infarction or ischemic stroke, refers to the localized brain tissue experiencing ischemic necrosis or softening due to disorders in brain blood supply, ischemia, and hypoxia. The precision rehabilitation nursing model for chronic disease management is a continuous, fixed, orderly, and efficient nursing model aimed at standardizing the clinical nursing process, reducing the wastage of medical resources, and improving the quality of medical services. AIM: To analyze the value of a precise rehabilitation nursing model for chronic disease management in patients with cerebral infarction. METHODS: Patients (n = 124) admitted to our hospital with cerebral infarction between November 2019 and November 2021 were enrolled as the study subjects. The random number table method was used to divide them into a conventional nursing intervention group (n = 61) and a model nursing intervention group (n = 63). Changes in the nursing index for the two groups were compared after conventional nursing intervention and precise rehabilitation intervention nursing for chronic disease management. RESULTS: Compared with the conventional intervention group, the model intervention group had a shorter time to clinical symptom relief (P < 0.05), lower Hamilton Anxiety Scale and Hamilton Depression Scale scores, a lower incidence of total complications (P < 0.05), a higher disease knowledge mastery rate, higher safety and quality, and a higher overall nursing satisfaction rate (P < 0.05). CONCLUSION: The precision rehabilitation nursing model for chronic disease management improves the clinical symptoms of patients with cerebral infarction, reducing the incidence of total complications and improving the clinical outcome of patients, and is worthy of application in clinical practice.

Sulfonated Azocalix[4]arene-Modified Metal-Organic Framework Nanosheets for Doxorubicin Removal from Serum.

Chemotherapy is one of the most commonly used methods for treating cancer, but its side effects severely limit its application and impair treatment effectiveness. Removing off-target chemotherapy drugs from the serum promptly through adsorption is the most direct approach to minimize their side effects. In this study, we synthesized a series of adsorption materials to remove the chemotherapy drug doxorubicin by modifying MOF nanosheets with sulfonated azocalix[4]arenes. The strong affinity of sulfonated azocalix[4]arenes for doxorubicin results in high adsorption strength (Langmuir adsorption constant = 2.45-5.73 L mg-1) and more complete removal of the drug. The extensive external surface area of the 2D nanosheets facilitates the exposure of a large number of accessible adsorption sites, which capture DOX molecules without internal diffusion, leading to a high adsorption rate (pseudo-second-order rate constant = 0.0058-0.0065 g mg-1 min-1). These adsorbents perform effectively in physiological environments and exhibit low cytotoxicity and good hemocompatibility. These features make them suitable for removing doxorubicin from serum during "drug capture" procedures. The optimal adsorbent can remove 91% of the clinical concentration of doxorubicin within 5 min.

Interleukin-1ß-Treated Mesenchymal Stem Cells Inhibit Inflammation in Hippocampal Astrocytes Through Exosome-Activated Nrf-2 Signaling.

BACKGROUND: Interleukin-1ß (IL-1)-treated mesenchymal stem cells (MSCs) and IL-1-MSCs-conditioned medium (CM) exert anti-inflammatory roles. Astrocytes are essential for the modulation of synaptic activity and neuronal homeostasis in the brain. Exosomes are the critical mediators in intercellular communication. However, the mechanism underlying the anti-inflammatory effect of IL-1-treated MSCs remains unknown. METHODS: In this study, exosomes (IL-1-Exo) were isolated from IL-1-treated MSCs. In addition, lipopolysaccharide (LPS)-treated hippocampal astrocytes and status epilepticus (SE) mice were treated with IL-1-Exo. Inflammatory activity, astrogliosis, and cognitive performance were measured to determine the effect of IL-1-Exo on inflammation. RESULTS: The results revealed that IL-1-Exo significantly inhibited LPS-induced astrogliosis and inflammatory responses of astrocytes. Also, IL-1-Exo reversed the LPS-induced effect on calcium signaling. The Nrf2 signaling pathway was associated with the effect of IL-1-Exo in LPS-treated astrocytes. Furthermore, IL-1-Exo reduced the inflammatory response and improved the cognitive performance of SE mice. CONCLUSION: The results suggest that IL-1-Exo inhibited LPS-induced inflammatory responses in astrocytes and SE mice and that the effect of IL-1-Exo was primarily mediated through the Nrf-2 signaling pathway. This study provides a new understanding of the molecular mechanism of inflammation-associated brain diseases and an avenue to develop nanotherapeutic agents for the treatment of inflammatory conditions in the brain.

Efficacy and safety of weekly rifapentine and isoniazid for tuberculosis prevention in Chinese silicosis patients: a randomized controlled trial.

OBJECTIVE: The aim was to evaluate the efficacy, safety and completion rate of 3-month, once-weekly rifapentine and isoniazid for tuberculosis (TB) prevention among Chinese silicosis patients. METHODS: Male silicosis patients without human immunodeficiency virus infection, aged 18 years to 65 years, with or without latent TB infection, were randomized 1:1 to receive rifapentine/isoniazid under direct observation (3RPT/INH group) or were untreated (observation group). Active TB incidence was compared between the two groups with 37 months of follow-up. Safety profile and complete rates were evaluated. RESULTS: A total of 1227 adults with silicosis were screened; 513 eligible participants were enrolled and assigned to 3RPT/INH (n = 254) vs. observation (n = 259). Twenty-eight participants were diagnosed with active TB, and 9 and 19 in the 3RPT/INH group and observation groups, respectively. In the intention-to-treat analysis, the cumulative active TB rate was 3.5% (9/254) in the 3RPT/INH group and 7.3% (19/259) in the observation group (log rank p 0.055). On per protocol analysis, the cumulative active TB rates were 0.7% (1/139) and 7.3% (19/259), respectively (log rank p 0.01). Owing to an unexpected high frequency of adverse events (70.4%) and Grade 3 or 4 AEs (7.9%), the completion rate of the 3RPT/INH regimen was 54.7% (139/254). Twenty-six (10.8%) participants had flu-like systemic drug reactions; five (2.1%) experienced hepatotoxicity. DISCUSSION: Weekly rifapentine/isoniazid prophylaxis prevented active TB among Chinese people with silicosis when taken, irrespective of LTBI screening; efficacy was reduced by lack of compliance. The regimen must be used with caution because of the high rates of adverse effects. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov number: NCT02430259.

Cross electro-nape-acupuncture ameliorates cerebral hemorrhage-induced brain damage by inhibiting necroptosis.

BACKGROUND: Receptor interacting protein kinase 1 (RIPK1)-mediated cell death, including apoptosis and necroptosis, belongs to programmed cell death. It has been reported that RIPK1-mediated necroptosis exists in lesions of cerebral hemorrhage (CH). Electroacupuncture, a treatment derived from traditional Chinese medicine, could improve neurological impairment in patients with brain injury. AIM: To investigate the protective role of cross electro-nape acupuncture (CENA) in CH, and clarify the potential mechanism. METHODS: CH rat models were established, and CENA was applied to the experimental rats. Neurological functions and encephaledema were then measured. Necrotic cells in the brain of rats with CH were evaluated by propidium iodide staining. Necroptosis was assessed by immunofluorescence. Activation of the necroptosis-related pathway was detected by western blot. Extraction of brain tissue, cerebrospinal fluid and serum samples was conducted to measure the expression and secretion of inflammatory cytokines by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay. RESULTS: The necroptotic marker p-MLKL was detectable in the brains of rats with CH. Next, we found that CENA could ameliorate neurological functions in rat models of CH. Moreover, the upregulation of RIPK1-mediated necroptosis-related molecules in the brains of rats with CH were inhibited by CENA. Further investigation revealed that CENA partially blocked the interaction between RIPK1 and RIPK3. Finally, in vivo assays showed that CENA decreased the expression of the inflammatory cytokines tumor necrosis factor-α, interleukin-6 and interleukin-8 in CH rat models. CONCLUSION: These findings revealed that CENA exerts a protective role in CH models by inhibiting RIPK1-mediated necroptosis.

[Normalized difference ratio pigment index for estimating chlorophyll and cartenoid contents of in leaves of rice].

The objective of the present study was (1) to construct new pigment indices based on making full use of all the spectral bands in the 350-2,500 nm region and (2) to compare the performance of these new pigment indices with that of the published normalized difference ratio pigment indices in estimating pigment content of rice. The 252 leaves of rice were sampled at different development stages, representing a wide range of pigment contents. The hyperspectral reflectance of leaves of rice and the corresponding chlorophyll contents and carotenoid contents were measured. A rigorous method using all the wavebands in the range of 350-2,500 nm was applied to generate all possible two-band normalized difference pigment indices, and then the linear models between these indices and chlorophyll and carotenoid contents were constructed. Finally, the index with the highest determination coefficients was selected as the optimal index for corresponding pigment. The model was tested and these selected indices were compared with the published indices. The result indicated that the indices [(R1729-R707)/(R1729+R707), (R1554-R572)/(R1554+R572), (R1729-R706)/(R1729+R706)), (R1536-R707)/(R1536+R707)] can relatively accurately estimate chlorophyll and cartenoid contents. The reference bands of the these new indices are mainly located in short wave infrared spectral region, which indicate that the spectral bands in the short wave infrared region are significant to construct normalized ratio pigment index, while the index bands of these indices are mostly in the region near 700 nm, and the longer bands of green region in the next place. Compared to the published indices, in general, the new indices give more accurate estimation of chlorophyll and carotenoid contents, or they behave the same as the best published index.

Identification of optimal hyperspectral bands for estimation of rice biophysical parameters.

The present study aims to identify the narrow spectral bands that are most suitable for characterizing rice biophysical parameters. The data used for this study come from ground-level hyperspectral reflectance measurements for five rice species at three levels of nitrogen fertilization during the growing period. Reflectance was measured in discrete narrow bands between 350 and 2,500 nm. Observed rice biophysical parameters included leaf area index (LAI), wet biomass and dry biomass. The stepwise regression method was applied to identify the optimal bands for rice biophysical parameter estimation. This research indicated that combinations of four narrow bands in stepwise regression models explained 69% to 83% variability for LAI, 56% to 73% for aboveground wet biomass and 70% to 83% for leaf wet biomass. An overwhelming proportion of rice information was in a particular portion of near infrared (NIR) (1,100-1,150 nm), red-edge (700-750 nm), and a longer portion of green (550-600 nm). These were followed by the moisture-sensitive NIR (950-1,000 nm), the intermediate portion of shortwave infrared (SWIR) (1 650-1,700 nm), and another portion of NIR (1,000-1,050 nm).

Optimal waveband identification for estimation of leaf area index of paddy rice.

The objectives of the study were to select suitable wavebands for rice leaf area index (LAI) estimation using the data acquired over a whole growing season, and to test the efficiency of the selected wavebands by comparing them with feature positions of rice canopy spectra. In this study, the field experiment in 2002 growing season was conducted at the experimental farm of Zhejiang University, Hangzhou, China. Measurements of hyperspectral reflectance (350 approximately 2500 nm) and corresponding LAI were made for a paddy rice canopy throughout the growing season. And three methods were employed to identify the optimal wavebands for paddy rice LAI estimation: correlation coefficient-based method, vegetation index-based method, and stepwise regression method. This research selected 15 wavebands in the region of 350~2 500 nm, which appeared to be the optimal wavebands for the paddy rice LAI estimation. Of the selected wavebands, the most frequently occurring wavebands were centered around 554, 675, 723, and 1 633 nm. They were followed by 444, 524, 576, 594, 804, 849, 974, 1 074, 1 219, 1 510, and 2 194 nm. Most of them made physical sense and had their counterparts in spectral known feature positions, which indicates the promising potential of the 15 selected wavebands for the retrieval of paddy rice LAI.

Quantifying biochemical variables of corn by hyperspectral reflectance at leaf scale.

To further develop the methods to remotely sense the biochemical content of plant canopies, we report the results of an experiment to estimate the concentrations of three biochemical variables of corn, i.e., nitrogen (N), crude fat (EE) and crude fiber (CF) concentrations, by spectral reflectance and the first derivative reflectance at fresh leaf scale. The correlations between spectral reflectance and the first derivative transformation and three biochemical variables were analyzed, and a set of estimation models were established using curve-fitting analyses. Coefficient of determination (R2), root mean square error (RMSE) and relative error of prediction (REP) of estimation models were calculated for the model quality evaluations, and the possible optimum estimation models of three biochemical variables were proposed, with R2 being 0.891, 0.698 and 0.480 for the estimation models of N, EE and CF concentrations, respectively. The results also indicate that using the first derivative reflectance was better than using raw spectral reflectance for all three biochemical variables estimation, and that the first derivative reflectances at 759 nm, 1954 nm and 2370 nm were most suitable to develop the estimation models of N, EE and CF concentrations, respectively. In addition, the high correlation coefficients of the theoretical and the measured biochemical parameters were obtained, especially for nitrogen (r=0.948).

[The estimation model of rice leaf area index using hyperspectral data based on support vector machine].

In order to compare the prediction powers between the best statistical model and SVM technique using each VI for rice LAI, the VIs are as independent variables in statistical models and are as net inputs in SVM, and the rice LAI are as dependent variables in statistical models and are as net outputs in SVM. Hyperspectral reflectance (350 to 2500 nm) data were recorded in two experiments involving four replicates of two rice cultivars ("Xiushui 110" and "Xieyou 9308"), three nitrogen levels (0, 120, 240 kg x ha(-1) N), and with a plant density of 45 plants x m(-2). The first experiment was seeded on 30 May 2004 and the second experiment on 15 June 2004. Both sets of seedlings were transplanted to the field one month later. Hyperspectral reflectance was ground-based and measured using Analytical Spectral Devices and 1 meter above the rice canopy. The solar angle compared to nadir was for all measurements less than 45 degrees and no disturbing clouds were observed. Hyperspectral reflectance was transformed to ten different vegetation indices including RVI, NDVI, NDVIgreen, SAVI, OSAVI, MSAVI, MCACI, TCARI/OSAVI, RDVI and RVI2, according to the width of TM bands of Ladsat-5. Different statistical models including linearity model, exponent model, power model and logarithm model, were analyzed using all samples' LAI and vegetation indices. Three good relationships including exponent relationship of NDVIgreen, power relationship of TCARI/OSAVI and power relationship of RV12 were selected based on the R2 of models. These three relationships were used to predict the LAI of rice through SVM models with different kernel functions including an analysis of variance kernel (ANOVA), a polynomial kernel (POLY) and a radial basic function kernel (RBF), and corresponding statistical models. The results show that all SVM models have lower RMSE values and higher estimation precision than corresponding statistical models; SVM with POLY kernel function using TCARI/OSAVI has the highest estimation precision for rice LAI compared to other models, and it's RMSE value is lower than corresponding statistical model by 11 percent points. Therefore, SVM has a high accuracy for learning and a good robustness for estimation of LAI of rice using hyperspectral data. Consequently, SVM provides a useful explorative tool for improvement of the relationships between VIs and rice LAI.

[Wavebands selection for rice information extraction based on spectral bands inter-correlation].

The hyperspectral remote sensing data usually involve hundreds or even thousands of narrow bands, which may be crucial for providing additional information with significant improvements over broad bands in quantifying biophysical and biochemical variables of agricultural crop. However, the huge data generated by hyperspectral systems, and the problems this presents for storage and analysis, have far prevented the routine use of such data. The objective of the present research was to identify the spectral bands in the visible and near-infrared range that were suitable for the study of rice. The hyperspectral reflectance of canopy in different development stages was measured in experimental field using a 1 nm-wide spectroradiometer but was aggregated to 10 nm-wide bandwidths to match the first spaceborne hyperspectral sensor, Hyperion. The correlation coefficients(r) between all the combinations of spectral bands were computed, and then they were converted to R2 , which constituted R2 matrices. The matrices were plotted against wavebands. The criterion of band selection is that the lower the R2 value, the less the redundancy between two wavebands while the higher R2 indicates that there is redundant information between two wavebands. According to the criterion, the wavebands corresponding to the first 100 minimum R2 values were selected from all canopy spectra collected on different dates. And then these bands were analyzed. The results indicate that the visible and infrared (NIR and SWIR) themselves contain redundant information. The wavebands containing abundant information of rice are located in specific bands in the longer wavelength portion of the visible region, with secondary clusters in red edge region, in strongly reflective near-infrared region with relatively higher reflectance, in one particular section of short wave near-infrared (SWIR) (1 530 nm) and in the second maximum reflectance region of SWIR (2 215 nm). Compared with the selected bands with other vegetation, rice seems to have three spectral regions of 400-410 nm, 630-650 nm and 1 520-1 540 nm, which exclusively depict the characteristics of rice. Moreover, this research identified 17 spectral bands in the visible and near-infrared region, which were 405, 565, 585, 605, 620, 640, 660, 680, 695, 705, 720, 740, 865, 910, 1 085, 1 530 and 2 215 nm. These bands contain the majority of the rice information content. A reduction in band number without significant information loss is important because it makes it possible to achieve fine spatial resolution without sacrificing the ability to characterize rice status.

Synthetic Dibenzoxanthene Derivatives Induce Apoptosis Through Mitochondrial Pathway in Human Hepatocellular Cancer Cells.

A new series of dibenzoxanthenes 4a-4f were synthesized through the nucleophilic substitution and characterized by NMR and MS spectra. Their antitumor activity was screened by MTT assay. Compounds (except 4b and 4c) displayed strong growth inhibitory effects against chosen five tumor cells under light irradiation. The molecular mechanism of compound-induced cell apoptosis was investigated by AO/EB staining, comet assay, DCFH-DA, JC-1 fluorescent probe, and western blotting. Compounds induced the apoptosis of HepG2 cells and DNA damage. Location assay showed that compounds entered the nucleus of tumor cells. Furthermore, it was found that compounds induced loss of mitochondrial membrane potential, acceleration of ROS production, and activation of caspse-3, caspase-7, and caspase-9 proteins. Compounds upregulated the expression of pro-apoptotic Bim and Bax and downregulated the expression of anti-apoptotic Bcl-xl and Bcl-2. These results indicated that compounds induced the apoptosis of HepG2 cells through ROS-mediated mitochondrial pathway. The induction of apoptosis by dibenzoxanthenes may provide an important mechanism for their cancer chemopreventive function.

Dibenzoxanthenes induce apoptosis and autophagy in HeLa cells by modeling the PI3K/Akt pathway.

A new series of dibenzoxanthene derivatives 4a-4d (4a: 1-oxo-5-bromo-11-cyano-13c-methoxy-1,13c-dihydroxyl-dibenzo[a,kl]xanthene, 4b: 1-oxo-5-bromo-11-cyano-13c-ethoxy-1,13c-dihydroxyl-dibenzo[a,kl]xanthene, 4c: 1-oxo-5-bromo-11-cyano-13c-propoxy-1,13c-dihydroxyl-dibenzo[a,kl]xanthene and 4d: 1-oxo-5-bromo-11-cyano-13c-butoxy-1,13c-dihydroxyl-dibenzo[a,kl]xanthene) were synthesized and the molecular mechanisms of anti-cancer activities were investigated. These compounds showed excellent anti-tumor activity against A549, Eca-109, HeLa, HepG2 and SGC-7901 cell lines. Compounds 4a-4d could effectively inhibit the migration and invasion of HeLa cells in wound healing and transwell assays. Compounds induced the DNA damage and arrested in cell cycle distribution at G0/G1 phase. Apoptosis induced by compounds was detected using morphological observation of nuclear changes and FITC-Annexin V/PI staining. Additionally, compounds also induced the autophagy of HeLa cells through observing AO staining and upregulated the expression of LC3II and Beclin-1 proteins. Furthermore, treatment with autophagy inhibitor 3-methyladenine induced an obvious decrease in apoptotic rate in HeLa cells. This indicated that autophagy further promoted the HeLa cells apoptosis. Compounds 4a-4d enhanced the intracellular Ca2+ and ROS. Then the mitochondrial membrane potential of HeLa cells was depolarized and the cytochrome C was released from mitochondria into cytoplasm. Activities of the apoptotic factors Bcl-2, Bax, caspase-3 were measured using western blotting. After HeLa cells were exposed to compounds, the expressions of PI3K and Akt protein were decreased. Compounds exhibit anti-cancer activity via apoptosis and autophagy through inhibition of PI3K/Akt signaling pathway in HeLa cells.

Isoliquiritigenin Induces Cytotoxicity in PC-12 Cells In Vitro.

Isoliquiritigenin (ISL) has been reported to have a wide range of biological activities. This study evaluated the cytotoxic effect of ISL on norvegicus pheochromocytoma cell line (PC-12 cells) and its possible molecular mechanism. The cytotoxicity in vitro of ISL against PC-12 cells was investigated by MTT assay. The migration and invasion of PC-12 cells were performed by scratch test and transwell assay. Apoptosis was evaluated by microscopy and flow cytometry. The reactive oxygen species (ROS) and mitochondrial membrane potential were studied by fluorescent microscopy. DNA damage of PC-12 cells was analyzed by comet assay. The protein expression of caspase, Bcl-2 family member, autophagy-associated protein Beclin-1, and LC3 was detected by western blot. The autophagy of PC-12 cells was investigated by acridine orange (AO) and monodansylcadaverine (MDC) staining. The IC50 value of ISL against PC-12 cell is 17.8 ± 1.8 µM. ISL could suppress PC-12 cell migration and invasion. AO/ethidium bromide staining and flow cytometry suggested that ISL caused apoptosis of PC-12 cells. Significant DNA damages of PC-12 cells treated with ISL were observed in a comet assay. ISL inhibited the cell growth of PC-12 cells at S phase. Exposure of PC-12 cells to ISL increased the levels of cellular reactive oxygen species (ROS) and decreased the mitochondrial membrane potential. Additionally, ISL trigged the release of cytochrome c from the mitochondria to the cytoplasm. The expression levels of caspase-9, caspase-3, caspase-7, Bax, and Bim were upregulated, whereas the expression levels of Bcl-2 and Bcl-x were downregulated. AO and monodansylcadaverine (MDC) staining assay showed that ISL caused autophagy of PC-12 cells. The upregulation of protein Beclin-1 and LC3 was observed in PC-12 cells. Therefore, the results show that ISL induces apoptosis of PC-12 cells through ROS-mediated activation of the intrinsic mitochondria-cytochrome c-caspase protease mechanism and causes the autophagy of PC-12 cells. Graphical Abstract The in vitro cytotoxicity, apoptosis, comet assay, ROS, mitochondrial membrane potential, cell cycle arrest, autophagy, and western blot induced by ISL were investigated.

Design, synthesis and evaluation of anticancer activity of ruthenium (II) polypyridyl complexes.

A new ligand PFPIP (PFPIP=2-(2,3,4,5,6-pentafluorophenyl)[4,5-f]imadazo [1,10]phenanthroline) and its four ruthenium(II) polypyridyl complexes [Ru(NN)2(PFPIP)](ClO4)2 (NN=dmb: 4,4'-dimethyl-2,2'-bipyridine, 1; bpy: 2,2'-bipyridine, 2; phen: 1,10-phenanthroline, 3; dmp: 2,9-dimethyl-1,10-phenanthroline, 4) were synthesized and characterized by elemental analysis, IR, 1H NMR, 13C NMR and ESI-MS. The cytotoxic activity in vitro of the ligand and complexes toward BEL-7402, A549, HeLa, HepG2 and MG-63 cell lines was evaluated using MTT method (MTT=(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide). Complexes 1, 3 and 4 show moderate cytotoxic effect on the cell growth in BEL-7402 cells with IC50 values of 32.1±0.9, 37.9±1.7 and 42.1±3.0µM, respectively. The apoptosis in BEL-7402 cell was investigated with AO/EB and Hoechst 33,258 staining methods. The autophagy in BEL-7402 cell induced by complexes was assayed using MDC staining cell nuclei. The cell invasion, reactive oxygen species (ROS), mitochondrial membrane potential, cell cycle arrest, cellular uptake, comet assay and wound healing were studied under a fluorescent microscope. The complexes can cause autophagy and inhibit the cell invasion, and increase the ROS levels and induce a decrease in the mitochondrial membrane potential. The expression of the proteins related with apoptosis induced by the complexes was assayed by western blot analysis.