Herpes simplex virus type 1 (HSV-1) is the most common virus, with an estimated infection rate of 60⁻95% among the adult population. Once infected, HSV-1 can remain latent in the host for a lifetime ...and be reactivated in patients with a compromised immune system. Reactivation of latent HSV-1 can also be achieved by other stimuli. Though acyclovir (ACV) is a classic drug for HSV-1 infection, ACV-resistant strains have been found in immune-compromised patients and drug toxicity has also been commonly reported. Therefore, there is an urge to search for new anti-HSV-1 agents. Natural products with potential anti-HSV-1 activity have the advantages of minimal side effects, reduced toxicity, and they exert their effect by various mechanisms. This paper will not only provide a reference for the safe dose of these agents if they are to be used in humans, referring to the interrelated data obtained from in vitro experiments, but also introduce the main pharmacodynamic mechanisms of traditional Chinese medicine (TCM) against HSV-1. Taken together, TCM functions as a potential source for HSV-1 therapy by direct (blocking viral attachment/absorption/penetration/replication) or indirect (reducing the susceptibility to HSV-1 or regulating autophagy) antiviral activities. The potential of these active components in the development of anti-HSV-1 drugs will also be described.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Rhubarb, a traditional herb, has been used in clinical practice for hundreds of years to cure constipation, but its mechanism is still not clear enough. Currently, growing evidence suggests that ...intestinal flora might be a potential target for the treatment of constipation. Thus, the aim of this study was to clarify the laxative effect of rhubarb via systematically analyzing the metagenome and metabolome of the gut microbiota. In this study, the laxative effects of rhubarb were investigated by loperamide-induced constipation in rats. The gut microbiota was determined by high-throughput sequencing of 16S rRNA gene. Ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry was used for fecal metabolomics analysis. The data showed that rhubarb could significantly shorten gastrointestinal transit time, increase fecal water content and defecation frequency, improve gastrointestinal hormone disruption, and protect the colon mucus layer. Analysis of 16S rRNA gene sequencing indicated that rhubarb could improve the disorder of intestinal microbiota in constipated rats. For example, beneficial bacteria such as
Ligilactobacillus
,
Limosilalactobacillus
, and
Prevotellaceae UCG-001
were remarkably increased, and pathogens such as
Escherichia-Shigella
were significantly decreased after rhubarb treatment. Additionally, the fecal metabolic profiles of constipated rats were improved by rhubarb. After rhubarb treatment, metabolites such as chenodeoxycholic acid, cholic acid, prostaglandin F2α, and α-linolenic acid were markedly increased in constipation rats; in contrast, the metabolites such as lithocholic acid, calcidiol, and 10-hydroxystearic acid were notably reduced in constipation rats. Moreover, correlation analysis indicated a close relationship between intestinal flora, fecal metabolites, and biochemical indices associated with constipation. In conclusion, the amelioration of rhubarb in constipation might modulate the intestinal microflora and its metabolism. Moreover, the application of fecal metabolomics could provide a new strategy to uncover the mechanism of herbal medicines.
Key points
•
Rhubarb could significantly improve gut microbiota disorder in constipation rats.
•
Rhubarb could markedly modulate the fecal metabolite profile of constipated rats.
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CEKLJ, DOBA, EMUNI, FZAB, GEOZS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
During cancer therapy, phagocytic clearance of dead cells plays a vital role in immune homeostasis. The nonapoptotic form of cell death, ferroptosis, exhibits extraordinary potential in tumor ...treatment. However, the phagocytosis mechanism that regulates the engulfment of ferroptotic cells remains unclear. Here, we establish a novel pathway for phagocytic clearance of ferroptotic cells that is different from canonical mechanisms by using diverse ferroptosis models evoked by GPX4 dysfunction/deficiency. We identified the oxidized phospholipid, 1-steaoryl-2-15-HpETE-sn-glycero-3-phosphatidylethanolamine (SAPE-OOH), as a key eat-me signal on the ferroptotic cell surface. Enriching the plasma membrane with SAPE-OOH increased the efficiency of phagocytosis of ferroptotic cells by macrophage, a process that was suppressed by lipoprotein-associated phospholipase A
. Ligand fishing, lipid blotting, and cellular thermal shift assay screened and identified TLR2 as a membrane receptor that directly recognized SAPE-OOH, which was further confirmed by TLR2 inhibitors and gene silencing studies. A mouse mammary tumor model of ferroptosis verified SAPE-OOH and TLR2 as critical players in the clearance of ferroptotic cells in vivo. Taken together, this work demonstrates that SAPE-OOH on ferroptotic cell surface acts as an eat-me signal and navigates phagocytosis by targeting TLR2 on macrophages.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Black phosphorus (P) has been considered as a promising candidate for anodes due to its ability to absorb a large amount of Li atoms. Unfortunately, lithiation of bulk black P induces huge structural ...deformation, which limits its application. Here, on the basis of the density functional theory calculation, we predict that the newly found two-dimensional (2D) black and blue P are good electrodes for high-capacity lithium-ion batteries. Our theoretical calculations indicate that, in contrast to bulk black P, the monolayer and double-layer black and blue P can maintain their layered structures during lithiation and delithiation cycles. Moreover, it is found that Li diffusion on the surfaces of black and blue P has relatively low energy barriers (<0.4 eV), and the single-layer blue P and double-layer black and blue P possess high charge capacities.
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IJS, KILJ, NUK, PNG, UL, UM
Autophagy is implicated in the pathogenesis of pulmonary arterial hypertension (PAH). We aimed to investigate whether the p62‐Keap1‐Nrf2 pathway affects the development of PAH by mediating autophagy. ...A PAH rat model was established using monocrotaline (MCT). Pulmonary artery smooth muscle cells (PASMCs) were extracted, and the changes in proliferation, migration, autophagy, and oxidative stress were analyzed following overexpression or knockdown of p62. The impact of p62 on the symptoms of PAH rats was assessed by the injection of an adenovirus overexpressing p62. We found that the knockdown of p62 increased the proliferation and migration of PASMCs, elevating the oxidative stress of PASMCs and upregulating gene expression of NADPH oxidases. Co‐IP assay results demonstrated that p62 interacted with Keap1. p62 knockdown enhanced Keap1 protein stability and Nrf2 ubiquitination. LC3II/I and ATG5 were expressed more often when p62 was knocked down. Treating with an inhibitor of autophagy reversed the impact of p62 knockdown on PASMCs. Nrf2 inhibitor treatment reduced the expression of Nrf2 and p62, while increasing the expression of Keap1, LC3II/I, and ATG5 in PASMCs. However, overexpressing p62 diminished mRVP, SPAP, and Fulton index in PAH rats and attenuated pulmonary vascular wall thickening. Overexpression of p62 also decreased the expression of Keap1, LC3II/I, and ATG5 and increased the nuclear expression of Nrf2 in PAH rats. Importantly, overexpression of p62 reduced oxidative stress and the NADPH oxidase expression in PAH rats. Overall, activation of the p62‐Keap1‐Nrf2 positive feedback signaling axis reduces the proliferation and migration of PASMCs and alleviates PAH by inhibiting autophagy and oxidative stress.
Activation of the p62‐Keap1‐Nrf2 positive feedback signaling axis reduces the proliferation and migration of PASMCs and alleviates PAH by inhibiting autophagy and oxidative stress.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
•Tribochemical wear mechanism at the sliding interface of fully hydroxylated silica (010) was studied.•Two kinds of rupture behaviors of surface siloxane bonds were observed.•Hydrolysis reaction ...played a crucial role in the occurrence of tribochemical wear.•The contribution of each rupture behavior to the surface wear was quantitatively understood.•Mechanical wear, characterized by the local lattice distortion at subsurface, was observed.
Reactive molecular dynamics (ReaxFF) simulations were used to find the atomic-level wear mechanisms occurring at the sliding interface of fully hydroxylated silica (010) as a function of an interfacial water amount. The results showed that there were two kinds of rupture behaviors of surface siloxane bonds. One is resulted from only hydrolysis reaction between surface siloxane bonds and water. The other is also caused by the hydrolysis reaction, but is assisted by the interfacial siloxane bonds. Both rupture behaviors directly lead to tribochemical wear on silica surfaces. In the presence of less than a full monolayer water, the degree of wear induced only by hydrolysis reaction is affected by the change of interfacial shearing actions caused by increasing water molecules. However, the degree of wear assisted by interfacial siloxane bonds is related to the dual role of interfacial water in interfacial siloxane bonds. It is also noted that the load-dependent probability that the occurrence of tribochemical wear is caused by the formation of an interfacial siloxane bond ranges from 18% to 37%. In addition, mechanical wear, characterized by the local lattice distortion at subsurface, was also observed in our simulations. This study shows that even though no interfacial siloxane bond is formed, tribochemical wear of silica can still occur due to stress corrosion, and provides further insights into the wear mechanism of silica.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Caffeine is a major component of xanthine alkaloids and commonly consumed in many popular beverages. Due to its occasional side effects, reduction of caffeine in a natural way is of great importance ...and economic significance. Recent studies reveal that caffeine can be converted into non-stimulatory theacrine in the rare tea plant Camellia assamica var. kucha (Kucha), which involves oxidation at the C8 and methylation at the N9 positions of caffeine. However, the underlying molecular mechanism remains unclear. Here, we identify the theacrine synthase CkTcS from Kucha, which possesses novel N9-methyltransferase activity using 1,3,7-trimethyluric acid but not caffeine as a substrate, confirming that C8 oxidation takes place prior to N9-methylation. The crystal structure of the CkTcS complex reveals the key residues that are required for the N9-methylation, providing insights into how caffeine N-methyltransferases in tea plants have evolved to catalyze regioselective N-methylation through fine tuning of their active sites. These results may guide the future development of decaffeinated drinks.
Motivated by recent experimental developments of graphitic-CN (g-CN) sheets, we investigate the suitability of hydrogen storage on Li decorated g-CN
via
first-principles calculations. We find that ...the binding energies of Li atoms are very large, ranging from 2.70 to 4.73 eV, which are significantly higher than the cohesive energy of bulk Li. Lithium atoms therefore tend to form 2D rather than 3D patterns on g-CN, promoting reversible hydrogen adsorption and desorption. Remarkably, the average adsorption energy of H
2
molecules falls in the 0.14-0.23 eV range, and the Li decorated CN shows a high theoretical gravimetric density of 10.81 wt%, which is favorable for massive hydrogen storage. Our results suggest that the Li decorated CN could be a promising hydrogen storage material under realistic conditions.
Motivated by recent experimental developments of graphitic-CN (g-CN) sheets, we investigate the suitability of hydrogen storage on Li decorated g-CN
via
first-principles calculations.
Lipid metabolism disorder is related to an increased risk of tumorigenesis and is involved in the rapid growth of cancer cells as well as the formation of metastatic lesions. Epidemiological studies ...have demonstrated that low-density lipoprotein (LDL) and oxidized low-density lipoprotein (ox-LDL) are closely associated with breast cancer, colorectal cancer, pancreatic cancer, and other malignancies, suggesting that LDL and ox-LDL play important roles during the occurrence and development of cancers. LDL can deliver cholesterol into cancer cells after binding to LDL receptor (LDLR). Activation of PI3K/Akt/mTOR signaling pathway induces transcription of the sterol regulatory element-binding proteins (SREBPs), which subsequently promotes cholesterol uptake and synthesis to meet the demand of cancer cells. Ox-LDL binds to the lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) and cluster of differentiation 36 (CD36) to induce mutations, resulting in inflammation, cell proliferation, and metastasis of cancer. Classic lipid-lowering drugs, statins, have been shown to reduce LDL levels in certain types of cancer. As LDL and ox-LDL play complicated roles in cancers, the potential therapeutic effect of targeting lipid metabolism in cancer therapy warrants more investigation.
The activation of pancreatic stellate cells (PSCs) plays a critical role in the progression of pancreatic fibrosis. Nuclear factor‐kappa B (NF‐κB) is associated with chronic pancreatitis (CP). ...Previous evidence indicated that NF‐κB in acinar cells played a double‐edged role upon pancreatic injury, whereas NF‐κB in inflammatory cells promoted the progression of CP. However, the effects of NF‐κB in PSCs have not been studied. In the present study, using two CP models and RNAi strategy of p65 in cultured PSCs, we found that the macrophage infiltration and MCP‐1 expression were increased, and the NF‐κBp65 protein level was elevated. NF‐κBp65 was co‐expressed with PSCs. In vitro, TGF‐β1 induced overexpression of the TGF‐β receptor 1, phosphorylated TGF‐β1–activated kinase 1 (p‐TAK1) and NF‐κB in the PSCs. Moreover, the concentration of MCP‐1 in the supernatant of activated PSCs was elevated. The migration of BMDMs was promoted by the supernatant of activated PSCs. Further knockdown of NF‐κBp65 in PSCs resulted in a decline of BMDM migration, accompanied by a lower production of MCP‐1. These findings indicate that TGF‐β1 can induce the activation of NF‐κB pathway in PSCs by regulating p‐TAK1, and the NF‐κB pathway in PSCs may be a target of chronic inflammation and fibrosis.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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