The Evolution of Single-Cell RNA Sequencing Technology and Application: Progress and Perspectives.

As an emerging sequencing technology, single-cell RNA sequencing (scRNA-Seq) has become a powerful tool for describing cell subpopulation classification and cell heterogeneity by achieving high-throughput and multidimensional analysis of individual cells and circumventing the shortcomings of traditional sequencing for detecting the average transcript level of cell populations. It has been applied to life science and medicine research fields such as tracking dynamic cell differentiation, revealing sensitive effector cells, and key molecular events of diseases. This review focuses on the recent technological innovations in scRNA-Seq, highlighting the latest research results with scRNA-Seq as the core technology in frontier research areas such as embryology, histology, oncology, and immunology. In addition, this review outlines the prospects for its innovative application in traditional Chinese medicine (TCM) research and discusses the key issues currently being addressed by scRNA-Seq and its great potential for exploring disease diagnostic targets and uncovering drug therapeutic targets in combination with multiomics technologies.

[Establishment and verification of quality evaluation method of Jizhi Syrup based on quantitative analysis of multi-components by single marker].

A quantitative analysis of multi-components by single marker(QAMS) method was established for the simultaneous determination of ephedrine hydrochloride, protocatechuic acid, 5-caffeoylquinic acid, 4-hydroxybenzoic acid, naringin, neohesperidin, glycyrrhizic acid, and praeruptorin A in Jizhi Syrup by high performance liquid chromatography(HPLC) with ultraviolet multi-wavelength detection system, and its feasibility in quality evaluation of Jizhi syrup was verified. With naringin as the internal reference substance, the relative correction factors and chromatographic peak localization methods of other seven components were respectively established at 210, 254, 280, and 320 nm. The method reproducibility was validated, and the result of QAMS were compared with those obtained by the external standard method(ESM) to verify the accuracy and feasibility of the method. The relative correction factors of ephedrine hydrochloride, protocatechuic acid, 5-caffeoylquinic acid, 4-hydroxybenzoic acid, neohesperidin, glycyrrhizic acid, and praeruptorin A with naringin as reference were 0.846, 0.582, 0.608, 0.293, 0.913, 2.207, and 0.940, respectively, which presented excellent reproducibility under different experimental conditions. Furthermore, QAMS and ESM showed no significant difference in the results for 15 batches of samples. Except protocatechuic acid and 5-caffeoylquinic acid, other six compounds were the exclusive components of single medicinal materials. In addition, glycyrrhizic acid and praeruptorin A were identified in the Jizhi Syrup for the first time, filling up the blank of no component detected in Glycyrrhizae Radix et Rhizoma and Peucedani Radix. The method established in this study is convenient, efficient, specific, accurate, and reliable, which can comprehensively and effectively evaluate the quality of Jizhi Syrup to ensure the safety and efficacy of this drug in clinical application.

Mesenchymal stem cells increase heme oxygenase 1-activated autophagy in treatment of acute liver failure.

In recent years, transplantation of mesenchymal stem cells (MSCs) has attracted much attention as a potential cell-based therapy for acute liver failure (ALF). As an inducible enzyme, heme oxygenase 1 (HO-1) has been reported to have cytoprotective, anti-apoptotic and immunoregulatory effects. Autophagy, a conserved catabolic process in cells, may be an important pathway for MSCs to treat ALF. In this study, we aimed to explore whether MSCs treat ALF by regulating autophagy and whether HO-1 was involved in the same pathway. Bone marrow-derived MSCs were isolated from Sprague-Dawley rats and cultured according to an established protocol. Co-culture systems of MSCs and hepatocytes were used to assess autophagy in the treatment of ALF. Meanwhile, MSCs were transplanted into rats with d-galactosamine (Gal)-induced ALF. Autophagy inhibitor (3-methyladenine, 3-MA), HO-1 inhibitor (zinc protoporphyrin, ZnPP) and PI3K specific inhibitor (LY294002) were employed in the study. Blood samples and liver tissues were collected before euthanasia. Survival rate, liver function, inflammatory factors, histology, Ki67 and TUNEL staining were determined. MSCs transplantation alleviated ALF both in vivo and in vitro. Autophagy and autophagy-related proteins were significantly up-regulated during MSCs treatment. 3-MA attenuated the therapeutic effect of MSCs. Administration of LY294002 before ALF induction inhibited hepatocyte autophagy. During the MSCs treatment, the HO-1 expression was increased, while inhibiting HO-1 attenuated the therapeutic effect of MSCs as well as hepatocyte autophagy. These findings suggested MSCs could alleviate ALF by increasing the HO-1 expression, which played an important role in activating autophagy through PI3K/AKT signaling pathway.

[Relationship between Autophagy and Curcumin-induced Anticancer Effect].

Curcumin is a polyphenol extracted from turmeric rhizome and has multiple pharmacological roles. Recently,its anticancer properties have been recognized. Also,curcumin regulates autophagy in tumor cells via signaling pathways including AMP-activated protein kinase,mammalian target of rapamycin,transcription factor EB,Beclin-1,B-cell lymphoma 2,and endoplasmic reticulum stress. Considering the complicated crosstalk between autophagy and apoptosis,in this article we summaize the mechanism of curcumin-induced autophagy and its effect on apoptosis,with an attempt to provide insights on tumor therapy.

[Effects of Pogostemon cablin on gastrointestinal function of rats with syndrome of damp retention in middle-jiao].

To investigate the effects of Pogostemon cablin(patchouli) on gastrointestinal function of rats with the syndrome of damp retention in middle-jiao, and explore its therapeutic mechanism. In this study, gastrointestinal function of rats with the syndrome of damp retention in middle-jiao was evaluated by multiple assays including gastric remnant rate, small intestine propelling rate, gastric juice quantity, pepsin activity and gastrointestinal tissue morphology. ELISA was used to detect gastrointestinal hormones including MTL, GAS, VIP and cytokines including TNF-α and interleukin 10 in rat serum. Real-time fluorescent quantitative PCR technique was used to detect relative mRNA expression of AQP3, AQP4 and AQP8 in gastric and colonic tissues to explore the mechanism of P. cablin in treatment of gastrointestinal functions. The results showed that middle and high dose of P. cablin (3.24, 6.48 g•kg⁻¹) could obviously decrease the gastric remnant rate, promote gastric emptying, increase the small intestine propelling rate(P<0.05), speed up the propulsive movement of gastrointestinal tract, increase the secretion and acidity of gastric juice, increase the activity of pepsin, and improve the injury of gastrointestinal tissue. All the doses of P. cablin could increase the concentration of MTL and GAS in serum, reduce the concentration of VIP, TNF-α and IL-10 in serum, decrease the mRNA expression of AQP3 in gastric and colonic tissues, and increase the expression levels of AQP4 and AQP8 in colonic tissues. The regulatory effects were better in middle and high dose groups. In conclusion, regulation of the levels of gastrointestinal hormones, inflammatory cytokines and aquaporins may be the paths for P. cablin to maintain normal gastrointestinal function of rats with the syndrome of damp retention in middle-jiao. The results of the study laid a foundation for clarifying the treatment mechanism of aromatic damp-resolving drugs for indications including damp retention in middle-jiao and transformation failure of spleen.

Mesenchymal stem cells ameliorate lipid metabolism through reducing mitochondrial damage of hepatocytes in the treatment of post-hepatectomy liver failure.

Hepatectomy is an effective therapeutic strategy for many benign and malignant liver diseases, while the complexity of liver anatomy and the difficulty of operation lead to complications after hepatectomy. Among them, post-hepatectomy liver failure (PHLF) is the main factor threatening the life of patients. At present, liver transplantation is an effective approach for PHLF. However, the application of liver transplantation has been largely limited due to the shortage of donors and the high cost of such operation. Therefore, it is urgently necessary to develop a new treatment for PHLF. Mesenchymal stem cells (MSCs) have become a new treatment regimen for liver diseases because of their easy access and low immunogenicity. Our study found that there were some subtle connections between MSCs and liver lipid metabolism in the PHLF model. We used MSC transplantation to treat PHLF induced by 90% hepatectomy. MSC transplantation could restore the mitochondrial function, promote the ß-oxidation of fatty acid (FA), and reduce the lipid accumulation of hepatocytes. In addition, interleukin 10 (IL-10), a cytokine with immunoregulatory function, had an important role in lipid metabolism. We also found that MSCs transplantation activated the mammalian target of rapamycin (mTOR) pathway. Therefore, we explored the relationship between mitochondrial damage and lipid metabolism abnormality or PHLF. MSCs improved mitochondrial function and corrected abnormal lipid metabolism by affecting the mTOR pathway in the treatment of PHLF. Collectively, MSC transplantation could be used as a potential treatment for PHLF.

[Source Apportionment of Ozone Pollution in Guangzhou: Case Study with the Application of Lagrangian Photochemical Trajectory Model].

A six-day ozone pollution episode in Guangzhou in early October 2018 was analyzed with the application of a Lagrangian photochemical trajectory model to trace the sources of ozone, quantify the contributions of different regions, and evaluate the effects of emission reduction measures targeted at different emission sectors and different precursors on ozone pollution. The results showed that during the ozone pollution episode, the maximum daily 8 h ozone exceeded 160 µg·m-3 and the highest value reached 271 µg·m-3. The average concentrations of nitrogen oxides and volatile organic compounds (VOCs) were (77.7±42.8) µg·m-3 and (71.9±56.2) µg·m-3, respectively. Aromatics and alkenes were the dominant reactive VOCs, with contributions of 38% and 30% to·OH reactivity and 51% and 16% to ozone formation potential, respectively. The ozone pollution in Guangzhou during this episode was affected by three types of air masses, with the primary source regions of Guangzhou, Guangdong Province, and regions outside Guangdong Province. For all three air mass types, ozone production in these source region was controlled by VOCs. Sensitivity tests showed that, in the primary source regions, reducing the emissions of VOCs is more effective than reducing NOx in terms of reducing ozone concentrations. Under the condition of full emission reduction, regulating traffic emissions could substantially reduce ozone levels by 14.6%-21.0% in Guangzhou, which was a more significant reduction than regulating controlled industry (8.4%-15.3%), power plant (0.9%-6.2%) and residential (2.3%-4.7%) emissions. However, the traffic emission reduction is not as effective (induced ozone reduction<10%) when the emissions reduction ratio is lower than 90%. In addition, biogenic emissions in the Pearl River Delta also substantially contributed to the ozone levels under certain circumstances, as indicated by the ozone reduction up to 19% when biogenic emissions were shut off.

Protective Properties of FOXO1 Inhibition in a Murine Model of Non-alcoholic Fatty Liver Disease Are Associated With Attenuation of ER Stress and Necroptosis.

AIM: The pathogenesis of non-alcoholic fatty liver disease is currently unclear, however, lipid accumulation leading to endoplasmic reticulum stress appears to be pivotal in the process. At present, FOXO1 is known to be involved in NAFLD progression. The relationship between necroptosis and non-alcoholic steatohepatitis has been of great research interest more recently. However, whether FOXO1 regulates ER stress and necroptosis in mice fed with a high fat diet is not clear. Therefore, in this study we analyzed the relationship between non-alcoholic steatohepatitis, ER stress, and necroptosis. MAIN METHODS: Male C57BL/6J mice were fed with an HFD for 14 weeks to induce non-alcoholic steatohepatitis. ER stress and activation of necroptosis in AML12 cells were evaluated after inhibition of FOXO1 in AML12 cells. In addition, mice were fed with AS1842856 for 14 weeks. Liver function and lipid accumulation were measured, and further, ER stress and necroptosis were evaluated by Western Blot and Transmission Electron Microscopy. KEY FINDINGS: Mice fed with a high fat diet showed high levels of FOXO1, accompanying activation of endoplasmic reticulum stress and necroptosis. Further, sustained PA stimulation caused ER stress and necroptosis in AML12 cells. At the same time, protein levels of FOXO1 increased significantly. Inhibition of FOXO1 with AS1842856 alleviated ER stress and necroptosis. Additionally, treatment of mice with a FOXO1 inhibitor ameliorated liver function after they were fed with a high fat diet, displaying better liver condition and lighter necroptosis. SIGNIFICANCE: Inhibition of FOXO1 attenuates ER stress and necroptosis in a mouse model of non-alcoholic steatohepatitis.

Mesenchymal Stem Cells Improve Glycometabolism and Liver Regeneration in the Treatment of Post-hepatectomy Liver Failure.

BACKGROUND: The mortality rate of post-hepatectomy liver failure (PHLF) remains very high, and liver transplantation is the only effective treatment regimen for PHLF. Cell transplantation is a potential treatment for liver diseases. Previous studies have proved that mesenchymal stem cells (MSCs) have immunomodulatory functions. In the present study, we found that MSCs promoted glycogen synthesis and liver regeneration in the treatment of PHLF. MSC transplantation also improved the survival rate of rats after 90% partial hepatectomy (PH). In our current study, we aimed to determine the efficacy and mechanism of MSC transplantation in the treatment of PHLF. METHODS: Mesenchymal stem cells were isolated from Sprague-Dawley rats and cultured using a standardized protocol. The MSCs were transplanted to treat acute liver failure induced by 90% PH. The therapeutic efficacy of MSCs on PHLF was verified through measuring alanine transaminase (ALT), aspartate aminotransferase (AST), international normalized ratio (INR), serum ammonia, liver weight to body weight ratio, blood glucose, and histology. To further study the mechanism of MSC transplantation in treatment for PHLF, we assessed the changes in the AKT/glycogen synthase kinase-3ß (GSK-3ß)/ß-catenin pathway. A-674563 (AKT inhibitor) and SB216763 (GSK-3ß inhibitor) were employed to validate our findings. SPSS version 19.0 was used for statistical analysis, and the independent-samples t-test was carried out to analyze the collected data. RESULTS: Mesenchymal stem cell transplantation attenuated the liver injury in acute liver failure induced by 90% PH. MSC transplantation improved the glucose metabolism and survival rate in the PHLF model. The effect of MSC transplantation on hepatocyte proliferation might be related to AKT/GSK-3ß/ß-catenin pathway. CONCLUSION: Mesenchymal stem cell transplantation could be use as a potential treatment for PHLF.

Lipometabolism and Glycometabolism in Liver Diseases.

The liver is the main metabolic organ in the body especially in lipometabolism and glycometabolism. Carbohydrates and fats disorders can result in insulin resistance in the liver. Metabolic imbalance can even lead to life-threatening conditions. Therefore, it is essential to maintain the normal metabolic function of the liver. When the liver is in a pathological state, liver metabolism homeostasis is damaged, and metabolic disorders will further aggravate liver disease. Consequently, it is essential to determine the relationship between liver diseases and metabolic disorders. Here we review a lot of evidence that liver diseases are closely related to lipometabolism and glycometabolism. Although the disorder of the liver metabolism is caused by different liver diseases, the break of metabolic balance is determined by changes in the state of the liver. We discuss the relationship between liver disease and metabolic changes, outline the process of how metabolic changes are regulated by liver diseases, and describe the role which metabolic changes play in the process and prognosis of liver disease.