Modulating cell stiffness for improved vascularization: leveraging the MIL-53(fe) for improved interaction of titanium implant and endothelial cell.

Vascularization plays a significant role in promoting the expedited process of bone regeneration while also enhancing the stability and viability of artificial bone implants. Although titanium alloy scaffolds were designed to mimic the porous structure of human bone tissues to facilitate vascularization in bone repair, their biological inertness restricted their broader utilization. The unique attribute of Metal-organic framework (MOF) MIL-53(Fe), known as "breathing", can facilitate the efficient adsorption of extracellular matrix proteins and thus provide the possibility for efficient interaction between scaffolds and cell adhesion molecules, which helps improve the bioactivity of the titanium alloy scaffolds. In this study, MIL-53(Fe) was synthesized in situ on the scaffold after hydrothermal treatment. The MIL-53(Fe) endowed the scaffold with superior protein absorption ability and preferable biocompatibility. The scaffolds have been shown to possess favorable osteogenesis and angiogenesis inducibility. It was indicated that MIL-53(Fe) modulated the mechanotransduction process of endothelial cells and induced increased cell stiffness by promoting the adsorption of adhesion-mediating extracellular matrix proteins to the scaffold, such as laminin, fibronectin, and perlecan et al., which contributed to the activation of the endothelial tip cell phenotype at sprouting angiogenesis. Therefore, this study effectively leveraged the intrinsic "breathing" properties of MIL-53 (Fe) to enhance the interaction between titanium alloy scaffolds and vascular endothelial cells, thereby facilitating the vascularization inducibility of the scaffold, particularly during the sprouting angiogenesis phase. This study indicates that MIL-53(Fe) coating represents a promising strategy to facilitate accelerated and sufficient vascularization and uncovers the scaffold-vessel interaction from a biomechanical perspective.

Magnetic graphene oxide nanocomposites induce cytotoxicity in ADSCs via GPX4 regulating ferroptosis.

Magnetic graphene oxide nanocomposites (MGO NPs) have been widely studied in biomedical applications. However, their cytotoxicity and underlying mechanisms remain unclear. In this study, the biosafety of MGO NPs was investigated, and the mechanism involved in ferroptosis was further explored. MGO can produce cytotoxicity in ADSCs, which is dependent on their concentration. Ferroptosis was involved in MGO NP-induced ADSC survival inhibition by increasing total ROS and lipid ROS accumulation as well as regulating the expression levels of ferroptosis-related genes and proteins. GPX4 played a critical role in the MGO NP-induced ADSC ferroptosis process, and overexpressing GPX4 suppressed ferroptosis to increase cell survival. This study provides a theoretical basis for the biosafety management of MGO NPs used in the field of biomedical treatment.

Cytotoxic steroidal saponins from the rhizomes of Paris fargesii var. Petiolata.

Phytochemical investigation on the rhizomes of Paris fargesii var. petiolata (Baker ex C. H. Wright) Wang et Tang led to the isolation of five previously undescribed steroidal saponins, parpetiosides A-E (1-5), and six known analogs (6-11). Their structures were established by extensive spectroscopic data analysis and chemical methods. Compound 5 was a rare steroidal saponin with disaccharide moiety linked at C-26 of dehydrokryptogenin that was hardly seen in the genus Paris. The cytotoxicities of the isolated compounds against three human cancer cell lines (U87, HepG2 and SGC-7901) were evaluated, and compound 1 displayed certain inhibitory effect with IC50 values of 8.02 ± 0.45, 8.24 ± 0.57 and 6.20 ± 0.79 µM, respectively. Moreover, the preliminary mechanism of 1 inhibiting the proliferation of the three cancer cell lines might be related to cell cycle distribution and the induction of S phase arrest.

Three New Steriodal Saponins from the Rhizomes of Tupistra chinensis Baker.

The phytochemical constituent investigation on the 70 % ethanol extract of the rhizomes of Tupistra chinensis Baker resulted in the isolation of three new steroidal saponins which were named tuchinosides A-C (1-3). Their structures were determined by extensive spectrum analysis and chemical evidence, especially 2D NMR and HR-ESI-MS techniques. In addition, the cytotoxicity of compounds 1-3 against several human cancer cell lines was evaluated.

Cytotoxic Steroidal Saponins Containing a Rare Fructosyl from the Rhizomes of Paris polyphylla var. latifolia.

A phytochemical investigation of the steroidal saponins from the rhizomes of Paris polyohylla var. latifolia led to the discovery and characterization of three new spirostanol saponins, papolatiosides A-C (1-3), and nine known compounds (4-12). Their structures were established via extensive spectroscopic data analysis and chemical methods. Interestingly, compounds 1 and 2 possessed a fructosyl in their oligosaccharide moiety, which is rare in natural product and was firstly reported in family Melanthiaceae. The cytotoxicity of these saponins against several human cancer cell lines was evaluated by a CCK-8 experiment. As a result, compound 1 exhibited a significant cytotoxic effect on LN229, U251, Capan-2, HeLa, and HepG2 cancer cells with IC50 values of 4.18 ± 0.31, 3.85 ± 0.44, 3.26 ± 0.34, 3.30 ± 0.38 and 4.32 ± 0.51 µM, respectively. In addition, the result of flow cytometry analysis indicated that compound 1 could induce apoptosis of glioma cells LN229. The underlying mechanism was explored by network pharmacology and western bolt experiments, which indicated that compound 1 could induce glioma cells LN229 apoptosis by regulating the EGFR/PI3K/Akt/mTOR pathway.

CN-3 increases TMZ sensitivity and induces ROS-dependent apoptosis and autophagy in TMZ-resistance glioblastoma.

Many glioma patients develop resistance to temozolomide (TMZ) treatment, resulting in reduced efficacy and survival rates. TMZ-resistant cell lines SHG44R and U87R, which highly express O6 -methylguanine DNA methyltransferase (MGMT) and P-gp, were established. CN-3, a new asterosaponin, showed cytotoxic effects on TMZ-resistant cells in a dose- and time-dependent manner via reactive oxygen species (ROS)-mediated apoptosis and autophagy. Transmission electron microscopy and monodansylcadaverine (MDC) staining showed turgidity of the mitochondria and autophagosomes in CN-3-treated SHG44R and U87R cells. The autophagy inhibitor 3-methyladenine was used to confirm the important role of autophagy in CN-3 cytotoxicity in TMZ-resistant cells. The ROS scavenger N-acetyl- l-cysteine (NAC) attenuated the levels of ROS induced by CN-3 and, therefore, rescued the CN-3 cytotoxic effect on the viability of SHG44R and U87R cells by Cell Counting Kit-8 assays and JuLI-Stage videos. MDC staining also confirmed that NAC rescued an autophagosome increase in CN-3-treated SHG44R and U87R cells. Western blotting revealed that CN-3 increased Bax, cleaved-caspase 3, cytochrome C, PARP-1, LC3-Ⅱ, and Beclin1, and decreased P-AKT, Bcl-2, and p62. Further rescue experiments revealed that CN-3 induced apoptosis and autophagy through ROS-mediated cytochrome C, cleaved-caspase 3, Bcl-2, P-AKT, PARP-1, and LC3-Ⅱ. In addition, CN-3 promoted SHG44R and U87R cells sensitive to TMZ by reducing the expression of P-gp, MGMT, and nuclear factor kappa B p65, and it had a synergistic cytotoxic effect with TMZ. Moreover, CN-3 disrupted the natural cycle arrest and inhibited the migration of SHG44R and U87R cells by promoting cyclin E1 and D1, and by decreasing P21, P27, N-cadherin, ß-catenin, transforming growth factor beta 1, and Smad2.

New Steroidal Saponins Isolated from the Rhizomes of Paris mairei.

The genus Paris is an excellent source of steroidal saponins that exhibit various bioactivities. Paris mairei is a unique species and has been widely used as folk medicine in Southwest China for a long time. With the help of chemical methods and modern spectra analysis, five new steroidal saponins, pamaiosides A-E (1-5), along with five known steroidal saponins 6-10, were isolated from the rhizomes of Paris mairei. The cytotoxicity of all the new saponins was evaluated against human pancreatic adenocarcinoma PANC-1 and BxPC3 cell lines.

CN-3 induces mitochondrial apoptosis in glioma via Ros-mediated PI3K/AKT pathway.

Recently we isolated CN-3, a new asterosaponin from starfish Culcita novaeguineae, and reported that asterosaponin arrests glioma cell cycle via SCUBE3. However, the multiple mechanisms underlying CN-3 anti-glioma action remains poorly known. Thus, the focus of this study was to evaluate the inhibitory effect of CN-3 on human glioma cells and its underlying molecular mechanisms. U87 and U251 cells were incubated with various concentrations of CN-3, and CCK-8, transmission electron microscopy, ICELLigence, TUNEL, flow cytometry, N-acetyl-L-cysteine, and western blot were conducted. As a result, it was found that CN-3 significantly inhibited U87 and U251 cell viability and proliferation in a time- and dose- dependent manner, and also induced mitochondrial apoptosis. Furthermore, we detected that CN-3 downregulated PI3K, P-Akt, AKT and BCL-2, and upregulated cytochrome C and BAX in U87 and U251 cells. Moreover, ROS triggered the inhibition and cell apoptosis for CN-3 via inactivation of P-Akt and activation of cytochrome C. In conclusion, these findings suggest that CN-3 may be a promising candidate for the development of a therapy of glioma.

Thymoquinone Attenuates Myocardial Ischemia/Reperfusion Injury Through Activation of SIRT1 Signaling.

BACKGROUND/AIMS: Myocardial ischemia/reperfusion (MI/R) injury is a leading factor responsible for damage in myocardial infarction, resulting in additional injury to cardiac tissues involved in oxidative stress, inflammation, and apoptosis. Thymoquinone (TQ), the main constituent of Nigella sativa L. seeds, has been reported to possess various biological activities. However, few reports regarding myocardial protection are available at present. Therefore, this study was conducted aiming to investigate the protective effect of TQ against MI/R injury and to clarify its potential mechanism. METHODS: MI/R injury models of isolated rat hearts and neonatal rat cardiomyocytes were established. The Langendorff isolated perfused heart system, triphenyltetrazolium chloride staining, gene transfection, TransLaser scanning confocal microscopy, and western blotting were employed to evaluate the cardioprotection effect of TQ against MI/R injury. RESULTS: Compared with the MI/R group, TQ treatment could remarkably improve left ventricular function, decrease myocardial infarct size and production of lactate dehydrogenase (LDH), and attenuate mitochondrial oxidative damage by elevating superoxide dismutase (SOD) activity and reducing production of hydrogen peroxide (H2O2) and malonaldehyde (MDA). Moreover, the cardioprotective effect of TQ was accompanied by up-regulated expression of SIRT1 and inhibition of p53 acetylation. Additionally, TQ treatment could also enhance mitochondrial function and reduce the number of apoptotic cardiomyocytes. Nonetheless, the cardioprotective effect of TQ could be mitigated by SIRT1 inhibitor sirtinol and SIRT1 siRNA, respectively, which was achieved through inhibition of the SIRT1 signaling pathway. CONCLUSIONS: The findings in this study demonstrate that TQ is efficient in attenuating MI/R injury through activation of the SIRT1 signaling pathway, which can thus reduce mitochondrial oxidative stress damage and cardiomyocyte apoptosis.

Cytotoxic Polyhydroxysteroidal Glycosides from Starfish Culcita novaeguineae.

Four new polyhydroxysteroidal glycosides-culcinosides A-D (1, 2, 4, and 7)-along with three known compounds-echinasteroside C (3), linckoside F (5), and linckoside L3 (6)-were isolated from the ethanol extract of starfish Culcita novaeguineae collected from the Xisha Islands of the South China Sea. The structures of new compounds were elucidated through extensive spectroscopic studies and chemical evidence, especially two-dimensional (2D) NMR techniques. The cytotoxicity of the new compounds against human glioblastoma cell lines U87, U251, and SHG44 were evaluated.

New Steroidal Saponins from the Rhizomes of Paris vietnamensis and Their Cytotoxicity.

Four new spirostanol saponins, named pavitnosides A-D (1-4), with six known steroidal saponins 5-10 were isolated from the rhizomes of Paris vietnamensis. Their chemical structures were determined based on extensive spectroscopic studies and chemical methods. The aglycones of pavitnoside B and pavitnoside C were not reported in previous work. The cytotoxicity of all saponins was evaluated against human glioblastoma U87MG and U251 cell lines. The new spirostanol saponin 1 displayed weak anti-proliferative activity against U87MG cell line and the known saponins 8 and 9 exhibited significant cytotoxicity against the two tumor cell lines, with IC50 values of 2.16 to 3.14 µM, but did not affect the growth of primary cultures of human astrocytes.

Five new alkaloids from the stem bark of Daphniphyllum macropodum.

Five new alkaloids, daphnicyclidins M and N (compounds 1 and 2) and calyciphyllines Q-S (compounds 3-5), along with four known ones, paxiphylline C (6), macropodumine B (7), macropodumine C (8) and daphnicyclidin A (9) were isolated from the stem bark of Daphniphyllum macropodum. Calyciphylline Q (3) is the first calyciphylline A derivative possessing a double bond between C-18 and C-19. Their structures and relative configurations were elucidated on the basis of spectroscopic methods, especially 2D NMR techniques. Compounds 1, 2, 8 and 9 exhibited cytotoxic activity against P-388 cells with IC50 values of 5.7, 6.5, 10.3 and 13.8 µM, respectively. Compounds 1 and 2 also showed cytotoxic activity against SGC-7901 cells with IC50 values of 22.4 and 25.6 µM.

Protective effects of Lycium barbarum polysaccharide on 6-OHDA-induced apoptosis in PC12 cells through the ROS-NO pathway.

Oxidative stress plays an important role in Parkinson's disease and other neurodegenerative disorders. Lycium barbarum polysaccharides (LBP), the main active ingredients extracted from the fruits of Lycium barbarum L., have been shown to be a potent antioxidant. In the present study, we investigated the protective effects, and the possible mechanism of action of LBP against 6-hydroxydopamine (6-OHDA)-induced apoptosis in PC12 cells. Our data demonstrated that LBP significantly reversed the 6-OHDA-induced decrease in cell viability, prevented 6-OHDA-induced changes in condensed nuclei and decreased the percentage of apoptotic cells in a dose-dependent manner. Furthermore, LBP also slowed the accumulation of reactive oxygen species (ROS) and nitric oxide (NO), decreased the level of protein-bound 3-nitrotyrosine (3-NT) and intracellular free Ca2+, and inhibiting the overexpression of nuclear factor κB (NF-κB), neuronal nitric oxide synthase (nNOS) and inducible nitric oxide synthase (iNOS). These results demonstrate that LBP prevents 6-OHDA-induced apoptosis in PC12 cells, at least in part through the ROS-NO pathway.

Black phosphorus quantum dot-modified ADSCs as a novel therapeutic for periodontitis bone loss coupling of osteogenesis and osteoimmunomodulation.

Alveolar bone defect repair remains a persistent clinical challenge for periodontitis treatment. The use of peripheral functional seed cells is a hot topic in periodontitis. Herein, we explored the cellular behaviors and osteogenic ability of adipose-derived mesenchymal stem cells (ADSCs) treated with black phosphorus quantum dots (BPQDs). Additionally, macrophage polarization, osteogenic effects and angiogenesis were investigated through the paracrine pathway regulated by BPQD-modified ADSCs. Our results demonstrated that BPQDs showed good biocompatibility with ADSCs and BPQD-modified ADSCs could improve the bone repair in vivo inflammatory microenvironment by regulating osteogenesis and osteoimmunomodulation. The BPQDs increased the osteogenic differentiation of ADSCs via the Wnt/ß-catenin and BMP2/SMAD5/Runx2 signaling pathway. In addition, BPQD-modified ADSCs promoted the osteogenic effect of BMSCs and facilitated the polarization of macrophages from M1 towards M2 phenotype transformation through the paracrine pathway in the periodontitis microenvironment. This strategy provides a novel idea for treatment of alveolar bone defects for periodontitis in the foreseeable future.

Two previously undescribed cholestanol saponins from the rhizomes of Paris fargesii var. petiolata.

Two previously undescribed cholestanol saponins, parpetiosides F - G (1-2), and six known analogs (3-8) were isolated from the rhizomes of Paris fargesii var. petiolata. Their structures were elucidated by extensive spectroscopic data analysis and chemical methods. Compound 1 was a rare 6/6/6/5/5 fused-rings cholestanol saponin with disaccharide moiety linked at C-26 of aglycone which was hardly seen in genus Paris. All of these compounds were discovered in this plant for the first time. In addition, the cytotoxicities of saponins (1-8) against three human cancer cell lines (U87, HepG2 and SGC-7901) were evaluated by CCK-8 method, and saponins 5-8 displayed certain cytotoxicities. The strong interactions between saponins 5-8 and SCUBE3, an oncogene for glioma cells, were displayed by molecular docking.

Two new saponins from the rhizomes of Paris yunnanensis Franch.

The phytochemical investigation on the rhizomes of Paris yunnanensis Franch. resulted in the discovery and characterisation of six compounds, including two new saponins named parisyunnanosides M-N (1-2), and four known ones (3-6). The structures of isolated compounds were determined by spectroscopic data analysis and chemical methods. Compound 2 is a pregnane-type saponin with a special α,ß-unsaturated carboxylic acid moiety at C-17, which is first discovered in genus Paris. The anti-inflammatory activity of the isolated compounds was assessed in vitro. The results demonstrated that compounds 3 and 4 could significantly inhibit the production of NO which was induced by LPS in RAW 264.7 cells with IC50 values of 0.67 ± 0.17 µM and 0.85 ± 0.12 µM, respectively.

Steroid and triterpenoid saponins from the rhizomes of Paris polyphylla var. stenophylla.

Five new saponins, including three steroid saponins, paristenoids A-C (1-3), and two triterpenoid saponins, paristenoids D-E (4-5), along with four known ones (6-9) were isolated from the rhizomes of Paris polyphylla var. stenophylla. The structures of the isolated compounds were identified mainly by detailed spectroscopic analysis, including extensive 1D and 2D NMR, MS, as well as chemical methods. Compound 3 is a new cyclocholestanol-type steroidal saponin with a rare 6/6/6/5/5 fused-rings cholestanol skeleton, and this skeleton has been first found from the genus Paris. The cytotoxicities of the isolated compounds against three human three glioma cell lines (U87MG, U251MG and SHG44) were evaluated, and compound 7 displayed certain inhibitory effect with IC50 values of 15.22 ± 1.73, 18.87 ± 1.81 and 17.64 ± 1.69 µmol·L-1, respectively.

Steriodal saponins from the rhizomes of Tupistra chinensis Baker.

Chemical constituent investigation on the n-BuOH extract of the rhizomes of Tupistra chinensis Baker leads to the isolation of ten compounds including eight undescribed furostanol saponins, tupischinosides A - H, and two known ones. The structures of isolated compounds were determined by extensive spectral analysis and chemical evidences. Interestingly, tupischinosides A and B, C and D, E and F, G and H were identified as four pairs of epimers. The cytotoxicity of tupischinosides A - H against human cancer cell lines U87, SHG44, U251, LN229 and HepG-2 was evaluated by CCK-8 method. As a result, tupischinosides A and C exhibited significant proliferation inhibitory effect on the tested cancer cells. On the contrary, the corresponding epimers, tupischinosides B and D, which only differ in the configuration of C-23 didn't exhibit any cytotoxicity to cancer cells. These results indicated that the stereochemistry of C-23 was crucial to the activity of the compounds.

The alkaloids with neuroprotective effect from the root bark of Ailanthus altissima.

The chemical constituent investigation on the root bark of Ailanthus altissima leads to the isolation of a new ß-carboline alkaloid, 14(S),15-dihydroxy-6-methoxy-ß-carboline (1), along with nine known alkaloids. The structure of new compound was elucidated on basis of extensive spectroscopic analysis, especially two-dimensional (2D) NMR techniques and the absolute configuration of C-14 was determined by ECD calculation. The neuroprotective effect of the isolated compounds on PC12 cells against the serum deprivation injury was evaluated by MTT method. As a result, compound 7 revealed protective effect on PC12 cells and the cell survival rate was significantly increased.

New steroidal saponins from the roots of Paris verticillata.

Four new polyhydroxylated steroidal saponins, parisverticillatosides A-D (1-4), together with four known spirostanol saponins (5-8) were isolated from the roots of Paris verticillata. Their structures were elucidated on the basis of extensive spectroscopic analysis and chemical evidences. The discovery of the new compounds 1-4 extended the diversity and complexity of this spirostanol saponin family. The saponins 5 and 6 exhibited cytotoxicities against two human glioma cell lines.