Base-Mediated Chemodivergent [4 + 1] and [2 + 1] Cycloadditions of N-Alkylpyridiniums and Enones.

Divergent synthesis of structurally different products from the same kinds of starting materials is highly synthetically useful but very challenging. Herein, we reported a base-mediated chemodivergent [4 + 1] and [2 + 1] cycloaddition of N-alkylpyridinium and enone under mild conditions, leading to furan-fused bicycles with high diastereoselectivity and spirobicycles, respectively, from moderate to high yields. N-Alkylpyridinium salts were modular nucleophilic transfer reagents and C1 synthons, which underwent tandem Michael addition to the α,ß-unsaturated ketones and cyclization under the base conditions. Late-stage derivatization of 4-propyldicyclohexylanone from an important industrial raw of liquid crystal display (LCD) screens was realized. In vitro, compound 3f exhibited good activities against human colon cancer cells (HCT116) with IC50 values in 9.82 ± 0.27 µM. Further biological evaluations investigated the mechanism of the effective inhibition of cell growth, including apoptosis ratio detection, cell cycle analysis, and migration capacity of HCT116 cells. In apoptosis effect studies, complex 3f increased the percentage of apoptotic HCT116 cells to 26.8% (15 µM).

[Research progress of chemerin in polycystic ovary syndrome].

As a multifunctional adipokine, chemerin plays a crucial role in various pathophysiological processes through endocrine and paracrine manner. It can bind to three known receptors (ChemR23, GPR1 and CCRL2) and participate in energy metabolism, glucose and lipid metabolism, and inflammation, especially in metabolic diseases. Polycystic ovary syndrome (PCOS) is one of the most common endocrine diseases, which seriously affects the normal life of women of childbearing age. Patients with PCOS have significantly increased serum levels of chemerin and high expression of chemerin in their ovaries. More and more studies have shown that chemerin is involved in the occurrence and development of PCOS by affecting obesity, insulin resistance, hyperandrogenism, oxidative stress and inflammatory response. This article mainly reviews the production, subtypes, function and receptors of chemerin protein, summarizes and discusses the research status of chemerin protein in PCOS from the perspectives of metabolism, reproduction and inflammation, and provides theoretical basis and reference for the clinical diagnosis and treatment of PCOS.

Synthesis, biological activity and mechanism of action of novel allosecurinine derivatives as potential antitumor agents.

Cancer with low survival rates is the second main cause of death among all diseases in the world and consequently, effective antineoplastic agents are urgently needed. Allosecurinine is a plant-derived indolicidine securinega alkaloid shown bioactivity. The object of this study is to investigate synthetic allosecurinine derivatives with considerable anticancer capacity against nine human cancer cell lines as well as mechanism of action. We synthesized twenty-three novel allosecurinine derivatives and evaluated their antitumor activity against nine cancer cell lines for 72 h by MTT and CCK8 assays. FCM was applied to analyze the apoptosis, mitochondrial membrane potential, DNA content, ROS production, CD11b expression. Western blot was selected to analyze the protein expression. Structure-activity relationships were established and potential anticancer lead BA-3 which induced differentiation of leukemia cells towards granulocytosis at low concentration and apoptosis at high concentration was identified. Mechanism studies showed that mitochondrial pathway mediated apoptosis within cancer cells with cell cycle blocking was induced by BA-3. In addition, western blot assays revealed that BA-3 induced expression of the proapoptotic factor Bax, p21 and reduced the levels of antiapoptotic protein such as Bcl-2, XIAP, YAP1, PARP, STAT3, p-STAT3, and c-Myc. Collectively, BA-3 was a lead compound for oncotherapy at least in part, through the STAT3 pathway. These results were an important step in further studies on allosecurinine-based antitumor agent development.

Bioactivities and Mechanisms of Action of Diphyllin and Its Derivatives: A Comprehensive Systematic Review.

Natural products are treasure houses for modern drug discovery. Diphyllin is a natural arylnaphthalene lignan lactone isolated from the leaf of Astilboides tabularis. Studies have found that it possesses plenty of bioactivity characteristics. In this paper, we reviewed the structure, bioactivity, and mechanism of action of diphyllin and its derivatives. The references were obtained from PubMed, Web of Science, and Science Direct databases up to August 2023. Papers without a bio-evaluation were excluded. Diphyllin and its derivatives have demonstrated V-ATPase inhibition, anti-tumor, anti-virus, anti-biofilm, anti-inflammatory, and anti-oxidant activities. The most studied activities of diphyllin and its derivatives are V-ATPase inhibition, anti-tumor activities, and anti-virus activities. Furthermore, V-ATPase inhibition activity is the mechanism of many bioactivities, including anti-tumor, anti-virus, and anti-inflammatory activities. We also found that the galactosylated modification of diphyllin is a common phenomenon in plants, and therefore, galactosylated modification is applied by researchers in the laboratory to obtain more excellent diphyllin derivatives. This review will provide useful information for the development of diphyllin-based anti-tumor and anti-virus compounds.

[UPLC-MS/MS determination of tanshinone â ¡A, salvianolic acid B and ginsenoside Rg1 in Fufang Danshen preparation in rat plasma and brain tissues].

A sensitive and specific ultra-performance liquid chromatography-mass spectrometry (UPLC-MS/MS) method was developed for analysis of tanshinone ⅡA(TSⅡA), salvianolic acid B(SAB) and ginsenoside Rg1 (GRg1) in rat plasma and brain tissues. Male healthy Sprague-Dawley(SD) rats were orally given single dose of Fufang Danshen preparation (TS ⅡA 60 mg•kg⁻¹, SAB 300 mg•kg⁻¹, GRg1 150 mg•kg⁻¹, borneol 300 mg•kg⁻¹), and their blood samples and brain tissues were collected at different time points. The drug plasma and brain tissue concentrations of the three analytes were determined by UPLC-MS/MS method. Subsequently, the main pharmacokinetics parameters of plasma and brain tissues were calculated by using Phoenix WinNolin 6.1 software. The methodological test showed that all of analytes in both plasma and brain homogenate exhibited a good linearity within the concentration range(r>0.992 2). Their mean recoveries were between 58.86% and 112.1%. Intra-day and inter-day precisions of the investigated components exhibited RSD≤9.7%, and the accuracy(RE) ranged from -9.68% to 8.20% at all quality control levels. The results of accuracy and stability meet the requirements for biopharmaceutical analysis. For TSⅡA, the pharmacokinetics parameters Tmax, Cmax, AUC0-t, MRTlast in the plasma were (1.58±0.081) h, (725.4±88.20) µg•L⁻¹, (2 101.3±124.85) µg•h•L⁻¹ and (3.66±0.05) h, respectively. For SAB, the pharmacokinetics parameters Tmax, Cmax, AUC0-t, MRTlast in the plasma were (1.29±0.21) h, (307.9±46.75) µg•L⁻¹, (537.4±88.24) µg•h•L⁻¹ and (2.08±0.11) h, respectively. For GRg1, the pharmacokinetics parameters Tmax, Cmax, AUC0-t, MRTlast in the plasma were (1.42±0.20) h, (460.38±154.60) µg•L⁻¹, (383.4±88.16) µg•h•L⁻¹ and (1.87±0.046) h, respectively. For TSⅡA, the pharmacokinetics parameters Tmax, Cmax, AUC0-t, MRTlast in the brain tissue were (0.75±0.22) h, (1.41±0.42) ng•g⁻¹, (4.34±2.48) ng•h•g⁻¹ and (4.00±1.90) h, respectively. For SAB, the pharmacokinetics parameters Tmax, Cmax, AUC0-t, MRTlast in the plasma were (1.08±0.20) h, (21.09±4.850) ng•g⁻¹, (14.83±3.160) ng•h•g⁻¹ and (0.99±0.08) h, respectively. For GRg1, the pharmacokinetics parameters Tmax, Cmax, AUC0-t, MRTlast in the plasma were (0.50±0.16) h, (130.96±54.220) ng•g⁻¹, (136.24±34.350) ng•h•g⁻¹ and (2.87±0.33) h, respectively. The developed method was successfully applied in pharmacokinetic studies on content of TS ⅡA, SAB and GRg1 in rat plasma and brain tissues.

Multidimensional Refinement Graph Convolutional Network With Robust Decouple Loss for Fine-Grained Skeleton-Based Action Recognition.

Graph convolutional networks (GCNs) have been widely used in skeleton-based action recognition. However, existing approaches are limited in fine-grained action recognition due to the similarity of interclass data. Moreover, the noisy data from pose extraction increase the challenge of fine-grained recognition. In this work, we propose a flexible attention block called channel-variable spatial-temporal attention (CVSTA) to enhance the discriminative power of spatial-temporal joints and obtain a more compact intraclass feature distribution. Based on CVSTA, we construct a multidimensional refinement GCN (MDR-GCN) that can improve the discrimination among channel-, joint-, and frame-level features for fine-grained actions. Furthermore, we propose a robust decouple loss (RDL) that significantly boosts the effect of the CVSTA and reduces the impact of noise. The proposed method combining MDR-GCN with RDL outperforms the known state-of-the-art skeleton-based approaches on fine-grained datasets, FineGym99 and FSD-10, and also on the coarse NTU-RGB + D 120 dataset and NTU-RGB + D X-view version. Our code is publicly available at https://github.com/dingyn-Reno/MDR-GCN.

Pharmacological activity and mechanism of pyrazines.

Heterocycles are common in the structure of drugs used clinically to deal with diseases. Such drugs usually contain nitrogen, oxygen and sulfur, which possess electron-accepting capacity and can form hydrogen bonds. These properties often bring enhanced target binding ability to these compounds when compared to alkanes. Pyrazine is a nitrogen-containing six-membered heterocyclic ring and many of its derivatives are identified as bioactive molecules. We review here the most active pyrazine compounds in terms of their structure, activity in vitro and in vivo (mainly antitumor activity) and the reported mechanisms of action. References have been downloaded through Web of Science, PubMed, Science Direct, Google Scholar and SciFinder Scholar. Publications reporting only the chemistry of pyrazine derivatives are beyond the scope of this review and have not been included. We found that compounds in which a pyrazine ring was fused into other heterocycles especially pyrrole or imidazole were the highly studied pyrazine derivatives, whose antineoplastic activity had been widely investigated. To the best of our knowledge, this is the first review of pyrazine derivatives and their bioactivity, especially their antitumor activity. This review should be useful for those engaged in development of medications based on heterocyclic compounds especially those based on pyrazine.

The effects of borneol on the pharmacokinetics and brain distribution of tanshinone IIA, salvianolic acid B and ginsenoside Rg1 in Fufang Danshen preparation in rats.

Fufang Danshen preparation (FDP) is consisted of Salviae Miltiorrhizar Radix et Rhizoma (Danshen), Notoginseng Radix et Rhizoma (Sanqi) and Borneolum Syntheticum (borneol). FDP is usually used to treat myocardial ischemia hypoxia, cerebral ischemia and alzheimer's disease, etc. In the treatment of cerebrovascular diseases, borneol is usually used to promote the absorption and distribution of the bioactive components to proper organs, especially to the brain. The purpose of this study is investigating the effects of borneol on the pharmacokinetics and brain distribution of tanshinone IIA (TS IIA), salvianolic acid B (SAB) and ginsenoside Rg1 in FDP. Male healthy Sprague-Dawley (SD) rats were given Danshen extracts, Sanqi extracts (Panax notoginsengsaponins) or simultaneously administered Danshenextracts, Sanqi extracts and borneol. Plasma and brain samples were collected at different points in time. The concentration of TS IIA, SAB and Rg1 was determined by UPLC-MS/MS method. The main pharmacokinetics parameters of plasma and brain tissue were calculated by using Phoenix WinNolin 6.1 software. In comparison with Danshen and Sanqi alone, there were significant differences in pharmacokinetic parameters of TS IIA, SAB and Rg1, and the brain distribution of SAB and TS IIA when Danshen, Sanqi and borneol were administrated together. Borneol statistically significant shortened tmax of TS IIA, SAB and Rg1 in plasma and brain, increased the bioavaiability of Rg1, inhibited metabolism of Rg1 and enhanced the transport of TS IIA and SAB to brain. These results indicated that borneol could affect the multiple targets components and produce synergistic effects. Through accelerating the intestinal absorption and brain distribution, borneol caused the effective ingredients of Danshen and Sanqi to play a quicker therapeutic role and improved the therapeutic effect.

Level of serum soluble Tim-3 expression in early-phase acute pancreatitis.

BACKGROUND/AIMS: T-cell immunoglobulin and mucin domain 3 (Tim-3) assumedly play a crucial immunomodulatory role in inflammatory response. Data on the potential role of soluble Tim-3 (sTim-3) in acute pancreatitis (AP) are scarce. We conducted a prospective clinical study to characterize its role in the early-phase AP. METHODS: In total, 44 patients with AP (16 mild and 28 none-mild) who presented within 24 hours on admission and 20 healthy volunteers (NC) were included in our study. Serum interleukin (IL)-6, IL-10, tumor necrosis factor (TNF)-α, and sTim-3 levels were detected using enzyme-linked immunosorbent assay (ELISA). RESULTS: Levels of the pro-inflammatory cytokines IL-6 and TNF-α and the anti-inflammatory cytokine IL-10 in the none-mild and mild groups were significantly elevated compared with those of the NC group. The sTim-3 levels of the none-mild and mild group were significantly increased compared with the NC. The sTim-3 level positively correlated with the IL-6 and TNF-α but showed no obvious correlations with the IL-10 level. The sTim-3 level positively correlated with the APACHE II score. CONCLUSION: The results indicate that sTim-3 participates in the early progression of AP by positively regulating the pro-inflammatory cytokines and that the measurement of serum sTim-3 is an early marker for predicting AP.

Tanshinone IIA Sodium Sulfonate Attenuates LPS-Induced Intestinal Injury in Mice.

BACKGROUND: Tanshinone IIA sodium sulfonate (TSS) is known to possess anti-inflammatory effects and has exhibited protective effects in various inflammatory conditions; however, its role in lipopolysaccharide- (LPS-) induced intestinal injury is still unknown. OBJECTIVE: The present study is designed to explore the role and possible mechanism of TSS in LPS-induced intestinal injury. METHODS: Male C57BL/6J mice, challenged with intraperitoneal LPS injection, were treated with or without TSS 0.5 h prior to LPS exposure. At 1, 6, and 12 h after LPS injection, mice were sacrificed, and the small intestine was excised. The intestinal tissue injury was analyzed by HE staining. Inflammatory factors (TNF-α, IL-1ß, and IL-6) in the intestinal tissue were examined by ELISA and RT-PCR. In addition, expressions of autophagy markers (microtubule-associated light chain 3 (LC3) and Beclin-1) were detected by western blot and RT-PCR. A number of autophagosomes were also observed under electron microscopy. RESULTS: TSS treatment significantly attenuated small intestinal epithelium injury induced by LPS. LPS-induced release of inflammatory mediators, including TNF-α, IL-1ß, and IL-6, were markedly inhibited by TSS. Furthermore, TSS treatment could effectively upregulate LPS-induced decrease of autophagy levels, as evidenced by the increased expression of LC3 and Beclin-1, and more autophagosomes. CONCLUSION: The protective effect of TSS on LPS-induced small intestinal injury may be attributed to the inhibition of inflammatory factors and promotion of autophagy levels. The present study may provide novel insight into the molecular mechanisms of TSS on the treatment of intestinal injury.