A Trojan horse biomimetic delivery system using mesenchymal stem cells for HIF-1α siRNA-loaded nanoparticles on retinal pigment epithelial cells under hypoxia environment.

AIM: To demonstrate the feasibility of mesenchymal stem cell (MSC)-mediated nano drug delivery, which was characterized by the "Trojan horse"-like transport of hypoxia-inducible factor-1α small interfering RNA (HIF-1α siRNA) between MSCs and retinal pigment epithelial cells (RPE) under hypoxia environment. METHODS: Plasmid and lentivirus targeting the human HIF-1α gene were designed and constructed. HIF-1α siRNA was encapsulated into poly(lactic-co-glycolic acid) nanoparticles (PLGA-NPs) through the water-in-oil-in-water (w/o/w) multiple emulsion technique. The effect of PLGA-NPs uptake on the expression of HIF-1α mRNA was tested in RPE cells by real-time quantitative polymerase chain reaction (qPCR) and additional transfected conditions were used as control, including lentivirus group, nude plasmid group and blank PLGA group. MSCs were transfected with the NPs and the transfection efficacy was evaluated by flow cytometry. Transwell co-culture system of transfected MSCs and RPE cells was constructed under hypoxia environment. The effects of MSC-loaded HIF-1α siRNA PLGA-NPs on proliferation, apoptosis, and migration of RPE cells were then evaluated. The effect of transfected MSCs on HIF-1α expression of RPE cells was analyzed by using qPCR at the time points 24h, 3d, and 7d. RESULTS: The average diameter of PLGA-NPs loaded with HIF siRNA was 314.1 nm and the zeta potential was -0.36 mV. The transfection efficiency of PLGA-NPs was 67.3%±5.2% into MSCs by using flow cytometry. Compared with the lentivirus group, the PLGA-NPs loaded with HIF-1α siRNA can effectively reduce the expression of HIF-1α mRNA up to 7d in RPE (0.63±0.05 at 7d, P<0.001). In the Transwell co-culture system of transfected MSCs and RPE, the abilities of proliferation (2.34±0.17, 2.40±0.28, 2.47±0.24 at 48h, F=0.23, P=0.80), apoptosis (14.83%±2.43%, 12.94%±2.19%, 12.39%±3.21%; F=0.70, P=0.53) and migration (124.5±7.78, 119.5±5.32, 130±9.89, F=1.33, P=0.33) of the RPE cells had no differences between MSC-loaded HIF-1α siRNA PLGA-NPs and other groups. The inhibition of PLGA on the HIF-1α mRNA expression in RPE cells could continue until the 7th day, the level of HIF-1α mRNA was lower than that of other groups (F=171.98, P<0.001). CONCLUSION: The delivery of PLGA-NPs loaded with HIF-1α siRNA carried by MSCs is found to be beneficial temporally for HIF-1α mRNA inhibition in RPE cells under hypoxia environment. The MSC-based bio-mimetic delivery of HIF-1α siRNA nanoparticles is a potential method for therapy against choroidal neovascularization.

The phenolic acids from Oplopanax elatus Nakai stems and their potential photo-damage prevention activity.

25 phenolic acids, including four new isolates, eurylophenosides A-D (1-4) and 21 known ones (5-25) were isolated and identified from the stems of Oplopanax elatus Nakai. Among the known compounds 5-9, 11-13, 16, 18-25 were isolated from the genus for the first time; 17 was first obtained from the plant; and the NMR data of 22 was reported here first. Meanwhile, the UVB-induced photodamage model of HaCaT cells was used to study the prevent-photodamage abilities of compounds 1-2, 4-8, 11-13 and 15-25 with a nontoxic concentration at 50 µM. Moreover, a dose-dependent experiment was conducted for active compounds at the concentration of 10, 25, and 50 µM, respectively. Consequently, pretreatment with compounds 1, 16, 17, 19, 20, 22, 24 and 25 could suppress the cell viability decreasing induced by UVB irradiation in a concentration-dependent manner. These results indicated that phenolic acids were one kind of material basis with prevent-photodamage activity of O. elatus.

Sesquiterpenes From Oplopanax elatus Stems and Their Anti-Photoaging Effects by Down-Regulating Matrix Metalloproteinase-1 Expression via Anti-Inflammation.

In the process of continuing to investigate ultraviolet b (UVB) irradiation protective constituents from Oplopanax elatus stems, nine new sesquiterpenes, named as eurylosesquiterpenosides A-D (1-4), eurylosesquiterpenols E-I (5-9), and ten known ones (10-19) were gained. Their structures were established by analysis of their NMR spectroscopic data, and electronic circular dichroism calculations were applied to define their absolute configurations. In addition, UVB induced HaCaT cells were used to study their anti-photoaging activities and mechanism. The results consolidated that compounds 7, 11, and 14 could improve the survival rate of HaCaT cells in concentration dependent manner at 10, 25, and 50 µM. Furthermore, western blot assay suggested that all of them could inhibit the expression of matrix metalloproteinase-1 (MMP-1), and increase the level of type I collagen markedly. Compounds 11 and 14 could reduce the phosphorylation of extracellular signal-regulated kinase and p38, respectively. Besides, compounds 7, 11, and 14 could significantly down-regulate the expression of inflammation related protein, such as tumor necrosis factor-α and cyclooxygenase-2, which indicated that they played anti-photoaging activities by reducing MMP-1 expression via down-regulating the production of inflammatory mediators and cytokines in UVB-induced HaCaT cells.

Correction to: The structure-activity relationship review of the main bioactive constituents of Morus genus plants.

The article The structure-activity relationship review of the main bioactive constituents of Morus genus plants, written by Jiejing Yan, Jingya Ruan, Peijian Huang, Fan Sun, Dandan Zheng, Yi Zhang and Tao Wang was originally published Online First without Open Access.

Anti-inflammatory Limonoids From Cortex Dictamni.

The root barks of perennial herb Dictamnus dasycarpus (Cortex Dictamni) were reported to be rich in anti-inflammation activity constituents, limonoids. Then, the investigation of anti-inflammation therapeutic limonoids from this plant was developed in the present study. Through the combination of various chromatographies isolation, six new limonoids, named dictamlimonol A (1), dictamlimonoside B (2), and dictamlimonols C-F (3-6), along with seven known ones (7-13), were obtained. Their structures were ascertained based on the extensive spectroscopic methods and ECD data analysis. Among them, compound 1 was the first 7,19-epoxy limonoid found in natural products. The anti-inflammatory effects of all limonoids were evaluated in lipopolysaccharide (LPS)-treated RAW 264.7 cell lines. Compounds 5, 7-11, and 13 were found to inhibit LPS-induced nitric oxide (NO) production. Moreover, dictamlimonol D (5), fraxinellone (11), and dasylactone A (13) were found to reduce the LPS-induced expressions of interleukin-6 (IL-6), tumor necrosis factor (TNF-α), inducible nitric oxide synthase (iNOS), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and cyclooxygenase-2 (COX-2) at the protein levels in a dose-dependent manner. These findings support that the administration of Cortex Dictamni may be beneficial for inflammation.

NMR and MS data for novel bioactive constituents from Pugionium cornutum L. Gaertn.

The data presented in this article are associated with the research article entitled "Bioactive Constituents Study of Pugionium cornutum L. Gaertn on Intestinal Motility" [1]. The aim of this data was to provide the 1D, 2D NMR and MS spectrum of novel bioactive compounds from P. cornutum.

The structure-activity relationship review of the main bioactive constituents of Morus genus plants.

Morus genus plants are mainly distributed in the temperate to tropical areas over the world and include 17 species and two subspecies. Due to their excellent pharmacological activity, security in food additives and high value in the national economy, Morus genus plants have drawn more and more attention in recent years. In the light of the references published over the last few decades, flavonoids, benzofurans, stilbenes, and Diels-Alder adducts have been reported to be the main bioactive constituents of Morus genus plants. This review summarizes the compounds with excellent bioactivities isolated from Morus genus plants as well as their structure-activity relationships (SARs), which might be useful for the further research and development of Morus genus plants. The aromatic heterocycles with excellent bioactivities isolated from Morus genus plants as well as their structure-activity relationships (SARs) were summarized.

Bioactive constituents study of Pugionium cornutum L. Gaertn on intestinal motility.

Thirty-one compounds were obtained and identified from the dried roots of Mongolian medicinal and edible plant, Pugionium cornutum L. Gaertn. Eight of them were new ones, and named as pugcornols A (1), B (2), C (3), and D (4), pugcornosides A (5), B (6), C (7), and D (8), respectively. Among them, 1-4 were rare naturally occurring thiohydantoin derivatives. Meanwhile, all the isolates were determined for their activities on isolated mice jejunum contraction, and ten of them increased height of the spontaneous contractions. Moreover, we partly clarified the mechanism of 5-(methylsulfinyl)-pentanenitrile (9), a characteristic compound in P. cornutum by using different kinds of inhibitor.

Comprehensive Chemical Profiling in the Ethanol Extract of Pluchea indica Aerial Parts by Liquid Chromatography/Mass Spectrometry Analysis of Its Silica Gel Column Chromatography Fractions.

Pluchea indica Less. is a medicine and food dual-use plant, which belongs to the Pluchea genus, Asteraceae family. Its main constituents are quinic acids, flavonoids, thiophenes, phenolic acids, as well as sesquiterpenes. In order to provide a comprehensive chemical profiling of P. indica, an orthogonal chromatography combining reverse-phase chromatography BEHC18 column with a normal-phase chromatography silica column as the separation system and a ESI-Q-Orbitrap MS as the detector in both positive and negative ion modes were used. According to the retention time (tR) and the exact mass-to-charge ratio (m/z), 67 compounds were unambiguously identified by comparing to the standard references. Moreover, 47 compounds were tentatively speculated on the basis of the rules of MS/MS fragmentation pattern and chromatographic elution order generalized from the above-mentioned reference standards. Among them, 10 of them were potentially novel.

Relationship between Structural Characteristics and Plant Sources along with Pharmacology Research of Quassinoids.

Quassinoids, one kind of triterpenoids with multiple bioactivities such as anti-cancer, anti-malarial, anti-oxidative, anti-microbial, anti-diabetic, anti-viral, and anti-inflammatory effects, have drawn much attention in recent years. Between 2004 and 2018, the structural characteristics and plant sources of 190 quassinoids were reported. Herein, the structure-activity relationships (SARs) of quassinoids along with the anti-cancer mechanisms of four representative quassinoids, eurycomanone, bruceine D, dehydrobruceine B, and brusatol are discussed. This review might be useful for further research and development of quassinoids.

Anti-inflammatory constituents from Cortex Dictamni.

Eight new compounds named as dictamalkosides A (1), B (2), C (3), dictamphenosides A (4), B (5), C (6), D (7) and E (8), as well as 23 known ones were obtained from the 70% EtOH extract of Cortex Dictamni. Their structures were ascertained based on the spectroscopic evidences. Among the known compounds, 14, 17-23, 25-28, and 31 were isolated from Dictamnus genus for the first time; 16 and 24 were firstly isolated from this plant. And the 13C NMR data of 14 was reported here for the first time. Moreover, compounds 1-8, 12, 18-21, 27 and 31 were found to exhibit potential inhibitory effect on LPS-induced NO production at 40 µM for RAW 264.7 macrophages, which suggested alkaloids and phenolic acids might be anti-inflammation therapeutic substance in Cortex Dictamni.

New Dammarane-Type Triterpenoid Saponins from Panax notoginseng Leaves and Their Nitric Oxide Inhibitory Activities.

Inflammation is a very common and important pathological process that can cause many diseases. The discovery of anti-inflammatory drugs and the treatment of inflammation are particularly essential. Dammarane-type triterpenoid saponins (PNS) were demonstrated to show anti-inflammatory effects in the leaves of Panax notoginseng. Chromatographies and spectral analysis methods were combined to isolate and identify PNS. Moreover, the nitric oxide (NO) inhibitory activities of all compounds were examined in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. As a result, eleven new dammarane-type triterpenoid saponins, notoginsenosides NL-A1-NL-A4 (1-4), NL-B1-NL-B3 (5-7), NL-C1-NL-C3 (8-10), and NL-D (11) were isolated, and their structures were identified by using various spectrometric techniques and chemical reactions. Among them, compounds 4 and 11 were characterized by the malonyl substitution at 3-position. The 3-malonyl substituted dammarane-type terpennoids were first obtained from natural products. In addition, compounds 1, 2, 5, 6, and 8-10 were found to play an important role in suppressing NO levels at 50 µM, without cytotoxicity. All inhibitory activities were found to be dose-dependent.

Separation and Bioactive Assay of 25R/S-Spirostanol Saponin Diastereomers from Yucca schidigera Roezl (Mojave) Stems.

In order to find a simple, generic, efficient separation method for 25R/S-spirostanol saponin diastereomers, the liquid chromatographic retention behaviors of C12 carbonylation and C12 unsubstituted 25R/S-spirostanol saponin diastereomers on different stationary phases (C8, C18, C30 columns) and different mobile phases (MeOH-1% CH3COOH and CH3CN-1% CH3COOH) were investigated. A C30 column was firstly found to offer the highest efficiency for the separation of this kind of diastereomers than C8 and C18 columns. Meanwhile, the analysis results indicated that both CH3CN-1% CH3COOH and MeOH-1% CH3COOH eluate systems were selective for C12 unsubstituted 25R/S-spirostanol saponin diastereomers, while MeOH-1% CH3COOH possessed better selectivity for C12 carbonylation ones. Using the abovementioned analysis method, six pairs of 25R/S-spirostanol saponin diastereomers 1a⁻6a and 1b⁻6b from Yucca schidigera Roezl (Mojave) were isolated successfully by using HPLC on C30 column for the first time. Among them, three pairs were new ones, named as (25R)-Yucca spirostanoside E1 (1a), (25S)-Yucca spirostanoside E1 (1b), (25R)-Yucca spirostanoside E2 (2a), (25S)-Yucca spirostanoside E2 (2b), (25R)-Yucca spirostanoside E3 (3a), (25S)-Yucca spirostanoside E3 (3b), respectively. Moreover, 3a, 5a, 6a, 3b⁻6b showed strong inhibitory activities on the growth of SW620 cell lines with the IC50 values of 12.02⁻69.17 µM.

Bioactive Constituents from the Aerial Parts of Pluchea indica Less.

Four new thiophenes, (3''R)-pluthiophenol (1), (3''R)-pluthiophenol-4''-acetate (2), 3''-ethoxy-(3''S)-pluthiophenol (3), 3''-ethoxy-(3''S)-pluthiophenol-4''-acetate (4), together with twenty-five known compounds were obtained from the 70% ethanol-water extract of the aerial parts of Pluchea indica Less. Their structures were elucidated by spectroscopic methods. Among the known isolates, compounds 7, 8, 11, 14, 15, 18, 20, 23, 25⁻27 were isolated from Asteraceae family firstly, while compounds 6, 9, 10, 12, 13, 16, 19, 21, 28 were isolated from Pluchea genus for the first time. Meanwhile, compounds 1, 2, 10, 13, 18, 23 displayed significant inhibitory activities on LPS-induced NO production at 40 µM from RAW 264.7 macrophages, while compounds 3, 4, 26⁻29 possessed moderate inhibitory effects.

[Hypoxia and hyperglycemia promote the proliferation and migration of human marrow mesenchymal stem cells in vitro].

OBJECTIVE: To investigate the cell proliferation, apoptosis and migration of human marrow mesenchymal stem cells (hMSCs) under hypoxia and hyperglycemia. METHODS: The hMSCs from healthy adults were isolated and harvested by density gradient centrifugation followed by adherent cultures. The cells was divided into four groups: control group (210 mL/L O2 with 5.56 mmol/L glucose), high glucose and normoxia group (210 mL/L O2 with 30 mmol/L glucose), normal glucose and hypoxia group (50 mL/L O2 with 5.56 mmol/L glucose) and high glucose and hypoxia group (50 mL/L O2 with 30 mmol/L glucose). The cells at the third passage were cultured in different groups. Then, we used cell counting kit-8 (CCK-8) to detect the proliferation of hMSCs, Transwell(TM) assay to examine the migration of hMSCs, and flow cytometry to observe the apoptosis of hMSCs at 24 hours. RESULTS: Compared with the control group, the proliferation rate of hMSCs increased in the other groups at 24 and 48 hours, and the maximum proliferation effect was found in high glucose and hypoxia group. Compared with the control group, the migration ability of hMSCs in the other groups was enhanced dramatically at 24 hours, whereas there was no significant difference in the apoptosis rate among the four groups. CONCLUSION: Both high glucose and hypoxia could improve the migration and proliferation of hMSCs, but they have no effect on apoptosis.