10-Secocycloartane (=9,19-cyclo-9,10-secolanostane) triterpenoid saponins: Huangqiyenins M-X from Astragalus membranaceus (Fisch.) Bge

Phytochemical investigations of the leaves of Astragalus membranaceus (Fisch.) Bge. have led to the isolation of 12 undescribed triterpenoid saponins named huangqiyenins M-X. The structures of the undescribed compounds were determined using NMR and HRESIMS data. The cytotoxicity of these compounds against the RKO and HT-29 colon cancer cell lines was evaluated. Among these compounds, huangqiyenin W exhibited the highest cytotoxic activity against RKO colon cancer cells, whereas huangqiyenin Q and W showed moderate cytotoxic activity against HT-29 colon cancer cells. The network pharmacology results indicated that STAT3, IL-2 and CXCR1 are the correlated targets of huangqiyenin W against colon cancer, with AGE-RAGE and Th17 cell differentiation as the key signaling pathways.

Association of apolipoprotein B with all-cause and cardiovascular mortality among adults: Results from the National Health and Nutrition Examination Surveys

BACKGROUND

Apolipoprotein B (apoB) is a crucial component that directly reflects the number of atherogenic lipoprotein particles and is closely related to atherosclerosis. However, there was an inconsistency among previous studies in its relationship with mortality. Using nationally representative data, we aimed to investigate the association of apoB with cardiovascular and all-cause mortality.

METHODS

We retrospectively included participants from the National Health and Nutrition Examination Survey (2007-2014), and mortality was ascertained through December 31, 2015. Hazard ratios (HRs) with 95% confidence intervals (CIs) of apoB in quartiles (Q1-Q4) for mortality risk were calculated using multivariable-adjusted Cox proportional hazards models, and restricted cubic spline regressions were performed to test dose relationships.

RESULTS

We enrolled 10,375 participants with a mean age of 46.3 years, of which 47.88% were men. During a mean follow-up time of 69.2 months, 533 (5.14%) and 91 (0.88%) deaths were due to all causes and cardiovascular disease, respectively. After adjusting for confounders, per SD, increment of apoB was associated with an elevated risk of cardiovascular mortality (HR, 1.13; 95% CI, 1.03-1.24). The risk of all-cause mortality was significantly reduced in the third quartile (Q3) of apoB (HR, 0.71; 95% CI, 0.56-0.91) compared with the reference quartile (Q1). Moreover, spline analyses showed that the relationship of apoB with all-cause mortality was U-shaped, and the threshold value was 108 mg/dL.

CONCLUSIONS

ApoB was linearly associated with increased risk of cardiovascular mortality and non-linearly associated with all-cause mortality in a U-shaped manner, independently of other cardiovascular risk factors.

Inflachromene attenuates seizure severity in mouse epilepsy models via inhibiting HMGB1 translocation

Epilepsy is not well controlled by current anti-seizure drugs (ASDs). High mobility group box 1 (HMGB1) is a DNA-binding protein in the nucleus regulating transcriptional activity and maintaining chromatin structure and DNA repair. In epileptic brains, HMGB1 is released by activated glia and neurons, interacting with various receptors like Toll-like receptor 4 (TLR4) and downstream glutamatergic NMDA receptor, thus enhancing neural excitability. But there is a lack of small-molecule drugs targeting the HMGB1-related pathways. In this study we evaluated the therapeutic potential of inflachromene (ICM), an HMGB-targeting small-molecule inhibitor, in mouse epilepsy models. Pentylenetetrazol-, kainic acid- and kindling-induced epilepsy models were established in mice. The mice were pre-treated with ICM (3, 10 mg/kg, i.p.). We showed that ICM pretreatment significantly reduced the severity of epileptic seizures in all the three epilepsy models. ICM (10 mg/kg) exerted the most apparent anti-seizure effect in kainic acid-induced epileptic status (SE) model. By immunohistochemical analysis of brain sections from kainic acid-induced SE mice, we found that kainic acid greatly enhanced HMGB1 translocation in the hippocampus, which was attenuated by ICM pretreatment in subregion- and cell type-dependent manners. Notably, in CA1 region, the seizure focus, ICM pretreatment mainly inhibited HMGB1 translocation in microglia. Furthermore, the anti-seizure effect of ICM was related to HMGB1 targeting, as pre-injection of anti-HMGB1 monoclonal antibody (5 mg/kg, i.p.) blocked the seizure-suppressing effect of ICM in kainic acid-induced SE model. In addition, ICM pretreatment significantly alleviated pyramidal neuronal loss and granule cell dispersion in kainic acid-induced SE model. These results demonstrate that ICM is an HMGB-targeting small molecule with anti-seizure potential, which may help develop a potential drug for treating epilepsy.

A new oleanane-type triterpenoid saponin with α-glucosidase inhibitory activity from Camellia nitidissima

A new oleanane-type triterpenoid saponin, 21β, 22α-di-O-angeloyl-15α, 16α, 28-trihydroxyolean-12-ene 3β-O-α-L-rhamnopyranosyl-(1→3)-α-D-xylopyranosyl-(1→3)-β-D-glucopyranoside (1), together with five known compounds (2-5), were isolated from Camellia nitidissima. Their structures were elucidated based on spectroscopic methods, including extensive NMR and MS spectra. Compound 1 showed potential inhibitory activity on α-glucosidase with the IC50 values of 185.9 ± 44.5 µmol/L.

Effects of Homogenization Heat Treatment on the Fe Micro-Segregation in Ti-1023 Titanium Alloy

The segregation of the Fe element in Ti-10V-2Fe-3Al titanium alloy (Ti-1023) can lead to the generation of beta flecks, which seriously affects the performance of Ti-1023 products. During the heat treatment (HT) process at a high temperature, the Fe element in Ti-1023 ingots will migrate, making its distribution more uniform and reducing the segregation index. In this paper, the control of Fe micro-segregation in Ti-1023 ingots by homogenization HT was investigated. Firstly, dissection sampling and SEM-EDS analysis methods were used to study the distribution pattern of the Fe element in the equiaxed grains in the core of Ti-1023 ingots. It was found that the Fe content in the grain gradually increased along with the radial direction from the core to the grain boundary. Then, the homogenization HT experiments and numerical simulations of Ti-1023 at different HT temperatures from 1050 °C to 1200 °C were carried out. The results showed that the uniformity of Fe element distribution within grain can be significantly improved by the homogenization HT. With increasing HT temperature, Fe atoms migration ability increases, and the uniformity of Fe element distribution improves. Homogenization HT at 1150 °C and 1200 °C for 12 h can effectively reduce the degree of Fe element segregation.

Possible causes of atherosclerosis: lncRNA COLCA1 induces oxidative stress in human coronary artery endothelial cells and impairs wound healing

Background

Atherosclerosis is the most common cause of cardiovascular disease, accompanied by high mortality and poor prognosis. Low-density lipoprotein (LDL) and its oxidized form oxidized low-density lipoprotein (oxLDL) play an important role in atherosclerosis. This article will explore the role of the lncRNA COLCA1 (colorectal cancer associated 1)/hsa-miR-371a-5p/SPP1 (secreted phosphoprotein 1) pathway in oxLDL in causing human coronary artery endothelial cells (HCAECs) inflammation and related biological function changes.

Methods

OxLDL was used to stimulate HCAECs. The inflammatory response and biological function changes of HCAECs were analyzed, total RNA-seq was performed on HCAECs before and after stimulation, and RT-Qpcr (real-time quantitative PCR) was used to verify the differential genes. Interference of the expression of COLCA1 in HCAECs was performed by siRNA interference technology to verify the role of COLCA1 in the biological function changes of HCAECs after oxLDL stimulation, and further prove that COLCA1 affects SPP1 through hsa-miR-371a-5p.

Results

OxLDL can affect the oxidative stress response of HCAECs, which in turn affects the apoptosis and wound healing ability of HCAECs. COLCA1 and SPP1 were highly expressed after oxLDL stimulation, while hsa-miR-371a-5p was the opposite. After COLCA1 interference, the oxidative stress level of HCAECs stimulated by oxLDL decreased, the apoptosis level also significantly decreased, and the wound healing ability was enhanced. After simultaneous COLCA1 interference and recovery of the expression of hsa-miR-371a-5p, these improved functions disappeared. The dual-luciferase assay confirmed that hsa-miR-371a-5p and COLCA1, hsa-miR-371a-5p and SPP1 has binding targets.

Conclusions

OxLDL can up-regulate the expression of COLCA1 in HCAECs, which in turn affects the intracellular COLCA1/hsa-miR-371a-5p/SPP1 pathway to regulate the level of oxidative stress in cells. This in turn affects the level of apoptosis and wound healing ability, which causes cells to produce a continuous inflammatory response.

Phloroglucinol derivatives rhotomensones A-G from Rhodomyrtus tomentosa

Undescribed phloroglucinol derivatives, rhotomensones A-G, and a known derivative rhodomyrtosone B, were isolated from the leaves of Rhodomyrtus tomentosa. Rhotomensones A-D and G have unreported structural characteristics, in which rhotomensone A substitutes a benzene ring, rhotomensones B-D are bonded with a 2-methylbutanoyl group, and rhotomensone G has two fewer carbons. The structures of these compounds were determined by NMR spectroscopy, circular dichroism (CD) spectroscopy and X-ray crystallography. The inhibitory activities against α-glucosidase of rhotomensones E and F were evaluated in vitro, with IC₅₀ values of 0.50 ± 0.14 mg/mL and 0.07 ± 0.02 mg/mL. Moreover, rhodomyrtosone B showed significant antibacterial activity against some bacteria, with MIC values ranging from 0.50 to 16.00 μg/mL.

Bioactive dammarane triterpenoid saponins from the leaves of Cyclocarya paliurus

Thirteen undescribed dammarane triterpenoid saponins (cypaliurusides A-M), including eleven seco-dammarane type triterpenoids, were isolated from Cyclocarya paliurus. Each of these compounds has the unique feature of having a monosaccharide attached to C-11, rather than C-12, compared to the same type of saponins found in this plant. The structures of them were determined by comprehensive analysis of 1D, 2D NMR and HRESIMS data. Cypaliuruside J showed significant α-glucosidase inhibitory effect with IC50 value of 2.22 ± 0.13 μM. In addition, Cypaliurusides F and K exhibited modest cytotoxic activities against selected human cancer cell lines in vitro, with IC50 values ranging from 4.61 ± 0.13 to 15.23 ± 3.88 μM.

An active catalytic system for Suzuki-Miyaura cross-coupling reactions using low levels of palladium loading

An easily available Pd(OAc)₂/(2-(anthracen-9-yl)-1H-inden-3-yl) dicyclohexylphosphine/toluene/ⁱPrOH/water catalytic system was developed, which shows high catalytic activity in the Suzuki-Miyaura cross-coupling reactions of a diverse array of aryl and heteroaryl chlorides with Pd loadings down to 0.01 mol%.

An efficient indenyl-derived phosphine ligand for the Suzuki–Miyaura coupling of sterically hindered aryl halides

An air-stable aryl substituted indenyl phosphine used in combination with Pd(OAc)₂ provides a highly efficient catalyst for the Suzuki–Miyaura cross-coupling reaction of sterically hindered aryl halides with aryl boronic acids.

2-Aryl-indenylphosphine ligands: design, synthesis and application in Pd-catalyzed Suzuki–Miyaura coupling reactions

A focused library of phosphine ligands was constructed for structural optimization. The catalyst can be used to perform the Suzuki–Miyaura cross-coupling reaction of aryl and heteroaryl chlorides.

Pd-indenyl-diphosphine: an effective catalyst for the preparation of triarylamines

A new Buchwald-type diphosphine ligand has been developed for applications in Pd-catalyzed amination reactions towards the preparation of triarylamines. The catalyst can be used to perform the amination of an adverse array of aryl and heteroaryl chlorides.

Efficient phosphine ligands for the one-pot palladium-catalyzed borylation/Suzuki–Miyaura cross-coupling reaction

An air-stable 2-(anthracen-9-yl)-1H-inden-3-yl dicyclohexylphosphine was used in palladium-catalyzed borylation/Suzuki–Miyaura cross-coupling reaction.

Phenylphosphinacalix[3]trifuran: synthesis, coordination and application in the Suzuki–Miyaura cross-coupling reaction in water

Phenylphosphinacalix[3]trifuran and supramolecular assemblies with palladium have been synthesized. Phenylphosphinacalix[3]trifuran affords turnover numbers as high as 3.05 × 10⁷ in Suzuki–Miyaura cross-coupling reactions in pure water.

A double-site absorption model fits to pharmacokinetic data of repaglinide in man

The plasma concentrations of repaglinide in 16 male subjects were determined after an oral dose of 4 mg. Two-peak concentrations in plasma were observed. A type of one-compartment model with double sites of drug absorption was developed and successfully used to fit the data. A good agreement between observed and predicted data was found in all subjects with correlation index r2 > 0.97. The corresponding pharmacokinetic parameters were estimated as follows: Tmax1 0.61 +/- 0.14 h, Tmax2 1.45 +/- 0.43 h, Cmax1 40.60 +/- 20.57 ng/ml, Cmax2 42.70 +/- 17.54 ng/ml, T1 0.12 +/- 0.07 h, T2 0.67 +/- 0.30 h and T3 1.03 +/- 0.35 h.