Analysis of the of Pb, Cd and As in decoction of Lindera aggregata (Sims) Kosterm. by PBET digestion in vitro/Caco-2 cell model and their cumulative risk assessment / 药学学报

Inductively coupled plasma mass spectrometry (ICP-MS) was applied to determine the concentrations of lead (Pb), cadmium (Cd) and arsenic (As) in Lindera aggregata (Sims) Kosterm. The physiologically based extraction test (PBET) digestion in vitro/Caco-2 cell model was established to investigate the bioaccessible contents of Pb, Cd and As in decoction of Lindera aggregata (Sims) Kosterm. The target-organ toxicity dose modification of HI method (TTD) was used to evaluate the cumulative risk caused by the combined exposure of the total levels of Pb, Cd and As in Lindera aggregata (Sims) Kosterm. and the bioaccessible contents in the decoction. The results showed that the total contents of Pb, Cd and As in 4 batches of samples were in the range of 2.901-3.872, 1.299-1.800 and 0.062-0.216 mg·kg-1, respectively. After transportation by Cacco-2 cells, the bioaccessible contents of Pb, Cd, and As in the decoction were in the range of 0.045-0.080, 0.070-0.112 and 0.004-0.018 mg·kg-1. The results of risk assessment showed that calculated by the total amounts of heavy metals in the Lindera aggregata (Sims) Kosterm., for the end points of nervous system, the cumulative risks of co-exposure of heavy metals in 3 batches of samples were of concern. After decoction and transportation by Caco-2 cells, for the end points of cardiovascular system, blood, nervous system, kidney and testis, the TTD modification of HI values of all batches of samples were less than 1, and the health risks were acceptable. The study provided methodology basis for a more objective assessment of the health risks of heavy metals and harmful elements in traditional Chinese medicine and for a more scientific limit standard of heavy metals and harmful elements.

Non clinical pharmacodynamic evaluation system of high-altitude hypoxic brain injury / 药学学报

The air at high altitude is thin and belongs to the environment of low temperature, low oxygen and low pressure. The human brain is the most sensitive to hypoxia. Hypoxia will cause dysfunction of the central nervous system, resulting in high-altitude hypoxic brain injury, including mild high altitude headache and more destructive high altitude cerebral edema (HACE). Recently, with more and more people work and live in high altitude areas, the development of high-altitude hypoxic brain injury drugs would produce great economic value and social significance. Non clinical pharmacodynamic evaluation is the basic of drug development, which plays a key role in improving the success rate of clinical transformation and reducing the risk of clinical research. This review summarizes the cell models and animal models, and the evaluation indicators usually used to explore the candidates of high-altitude hypoxic brain injury. We aim at establishing a standardized non clinical efficacy evaluation system for high altitude hypoxic encephalopathy, and provide a standardized reference for drug development in hypoxic encephalopathy at high altitude at nonclinical stage.

Establishment of a screening cell model for cannabinoid type 1 receptor agonists / 药学学报

Cannabinoid receptors are one of the most expressed G protein-coupled receptors in the central nervous system, which are potential drug targets for inflammation, pain and drug abuse. Cannabinoid receptors are composed of type 1 receptor (CB1R), type 2 receptor (CB2R) and other receptors, of which CB1R plays a vital role in regulating central memory, cognition, and motor function. Therefore, screening CB1R agonists has potential value in treating nervous system diseases. In this study, the intracellular loop 3 (ICL3) domain of CB1R was replaced with a circular-permutated enhanced green fluorescent protein (cpEGFP). After infecting HEK 293T cells with lentivirus particles, we obtained a stable cell line that was overexpressed human CB1R-cpEGFP after puromycin selection. The interaction between receptor agonists and CB1R led to the change of receptor conformation, resulting in de-protonation of the EGFP, and enhancing the fluorescence intensity. Therefore, active CB1R compounds could be verified by measuring the fluorescence intensity. Using CB1R agonist arachidonyl-2′-chloroethylamide (ACEA) as a positive control to evaluate the reliability of this model, studies have shown that ACEA could induce receptor activation and increase fluorescence intensity, while antagonist rimonabant inhibited receptor activation with unchanged fluorescence intensity. In conclusion, this study successfully constructed a fluorescent probe screening model for CB1R agonists.

Effect of Angelica dahurica coumarins on the transport behavior of puerarin across blood-brain barrier in vitro and in vivo / 药学学报

A BBB co-culture cell model consisting of rat brain microvascular endothelial cells (BMEC) and astrocytes (AS) was established to study the effect of Angelica dahurica coumarins on the transport behavior of puerarin across blood-brain barrier (BBB) in vitro and in vivo. The barrier function of this model was evaluated by measuring the transendothelial resistance, phenol red permeability and BBB related protein expression. The permeability assay and western blot methods were performed to study the effects of Angelica dahurica coumarins on the BBB permeability and the expression of BBB related protein. The animal experiment protocols in this study were approved by the Animal Ethics Committee of Xi'an Jiaotong University (Animal Ethics No.: 2021-1329). The results showed that the established BMEC/AS co-culture model could be used to evaluate drug transport across BBB in vitro. After combined with Angelica dahurica coumarins, the transport capacity of puerarin was significantly increased in vitro and in vivo. Additionally, Angelica dahurica coumarins enhanced BBB permeability and inhibited the protein expression of P-glycoprotein (P-gp), zonula occludens-1 (ZO-1) and occludin. Angelica dahurica coumarins might increase BBB permeability by inhibiting the expression of P-gp and tight junction protein, thereby increasing the content of puerarin in brain tissue.

Overview and prospects of an in vitro cell model for studying liver fibrosis / 中华肝脏病杂志

Liver fibrosis incidence and adverse outcomes are high; however, there are no known chemical drugs or biological agents that are specific and effective for treatment. The paucity of a robust and realistic in vitro model for liver fibrosis is one of the major causes hindering anti-liver fibrosis drug development. This article summarizes the latest progress in the development of in vitro cell models for liver fibrosis, with a focus based on the analysis of induction and activation of hepatic stellate cells, cell co-culture, and 3D model co-construction, as well as concurrent potential methods based on hepatic sinusoidal endothelial cell establishment.

Application of cellular metabolomics in central nervous system diseases / 药学实践杂志

Cell metabolomics is an important branch of metabolomics, which could dynamically monitor cell response and metabolic changes after drugs acting on cells, and look for potential biomarkers. Cell metabolomics has been widely used in illustration of disease mechanism, evaluation of drug efficacy and development of new drug through elucidating the pathophysiological mechanism of the disease and the effect of drug treatment intervention. The researches process of cellular metabolomics and its application in central nervous system diseases were reviewed in order to provide theoretical basis for in-depth study of the pathogenesis and prevention and treatment of central nervous system diseases.

Establishment of a CFTR-based detection method for the second messenger cAMP in the cytoplasm / 中国应用生理学杂志

Objective: To establish a detection method based on Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) that can sensitively detect the second messenger cyclic AMP (cAMP) in the cytoplasm. Methods: The eukaryotic expression vectors of CFTR and YFP-H148Q / I152L were constructed respectively. FRT cells co-expressing CFTR and YFP-H148Q / I152L were obtained by liposome transfection. The expression of CFTR and YFP-H148Q / I152L in FRT cells was observed by an inverted fluorescence microscopy, and flow cytometry was used to detect the purity of cells; The cell model was identified by the fluorescence quenching kinetics test. The validation of the cell model which could screen CFTR modulators was verified by the fluorescence quenching kinetics experiments. The radioimmunoassay was used to detect the cAMP concentration in cytoplasm after adding CFTR activator. Results: The results of the inverted fluorescence microscope showed that CFTR was expressed in the cell membrane and YFP-H148Q / I152L was expressed in the cytoplasm of FRT cells. The FRT cell model stably co-expressing ANO1 and YFP-H148Q / I152L was successfully constructed. The model could screen CFTR modulators, and the slope of fluorescence change and the concentration of CFTR modulators were in a dose-dependent manner. The slope of the fluorescence could reflect the cAMP concentration in the cytoplasm. The cell model could sensitively detect the intracellular cAMP concentration. Conclusion: The cell model could efficiently and sensitively detect the second messenger cAMP concentration in the cytoplasm, and it provided a simple and efficient method for the study of other targets associated cAMP signal.

Establishment of a culture system for human nasal mucosa organoids with controllable differentiation / 南方医科大学学报

OBJECTIVE@#To establish a culture system for human nasal mucosal organoids with controllable differentiation to reproduce the structure and function of the source tissue through staged expansion-differentiation culture.@*METHODS@#Fresh samples of surgically resected middle turbinate and nasal polyp tissues were collected, from which the nasal mucosa epithelial cells were isolated by enzymatic digestion and filtration for continuous culture at the air-liquid interface for expansion (EO group) or staged culture for expansion and differentiation (DO group). Immunohistochemical staining was used to characterize the structure, cellular composition and ciliary function of nasal mucosal organoids in the two groups. The secretion function of the differentiated nasal mucosal organoids in DO group was evaluated using PAS staining.@*RESULTS@#Both of the two organoid culture systems yielded vacuolar or solid spherical 3D organoids, and their diameters increased progressively with time. On day 16 of culture, more vacuolar organoids occurred in DO group, while more solid spherical organoids were seen in EO group, and the proportion of vacuoles was significantly greater in DO group than in EO group [(54.67±13.26)% vs (21.67±8.57)%, P < 0.05]. Short tandem repeat (STR) test of the nasal mucosal organoids and the source tissue showed a 100% match between them. On day 21 of culture, scanning and transmission electron microscopy of the nasal mucosal organoids identified ultrastructure of cilia in DO group and short villi structure in most of the organoids in EO group. Immunohistochemical staining showed positivity for P63 (basal cells), β-tubulin (ciliated columnar cells), and MUC5AC (goblet cells) in the organoids. Compared with those in EO group, the organoids in DO group showed significantly greater percentages of ciliated cells [(7.95±1.81)% vs (27.04±5.91)%, P < 0.05] and goblet cells [(14.46±0.93)% vs (39.85±5.43)%, P < 0.05) with a similar percentage of basal cells [(56.91±14.12)% vs (53.42±15.77)%, P > 0.05]. The differentiated nasal mucosal organoids in DO group were positively stained for glycogen.@*CONCLUSION@#The staged expansion-differentiation culture method allows more stable and prolonged growth of the cultured cells in vitro to produce organoids with controllable differentiation closely resembling the morphological structure and functions (ciliary function and secretory function) of the source tissue.

Construction and identification of a HEK293 cell line with stable TrxR1 overexpression / 南方医科大学学报

OBJECTIVE@#To construct a HEK293 cell line stably overexpressing TrxR1 as a cell model for functional study of TrxR1 and screening of TrxR1-targeting drugs.@*METHODS@#TrxR1 gene was amplified by PCR and ligated with the lentivirus expression vector pLVX-Puro, which was transformed into Escherichia coli and identified by Sanger dideoxy sequencing. HEK293 cells were infected with the recombinant lentivirus vector (pLVX-Puro-TXNRD1) and screened with Puromycin for cell clones with stable TrxR1 overexpression (HEK293-TrxR1-OE cells). HEK293-TrxR1-OE cells, along with HEK293 cells infected with pLVX-Puro vector (HEK293-NC) and normal HEK293 cells, were tested for mRNA and protein expression levels of TrxR1 using RT-qPCR and Western blotting. TrxR1 enzyme activity in the cells was evaluated with insulin endpoint assay and TRFS-green probe imaging. The sensitivity of the cells to auranofin, a specific TrxR1 inhibitor, was determined with CCK8 assay.@*RESULTS@#TrxR1 gene was successfully inserted into the lentiviral vector pLVX-Puro as confirmed by DNA sequencing. The enzyme activity and mRNA and protein expression levels of TrxR1 were significantly higher in HEK293-TrxR1-OE cells than in HEK293 and HEK293-NC cells (P < 0.005). The inhibitory effects of auranofin on proliferation and cellular TrxR1 enzyme activity were significantly attenuated in HEK293-TrxR1-OE cells as compared with HEK293 and HEK293-NC cells (P < 0.005).@*CONCLUSION@#We successfully obtained a HEK293 cell line with stable TrxR1 overexpression, which shows resistance to auranofin and can be used for screening TrxR1 targeting drugs.

Establishment of rabbit dry eye cells model and evaluation of its biological characteristics / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To further explore effective drugs for dry eye treatment by isolating and culturing lacrimal gland epithelial cells<i> in vitro</i>, establishing a dry eye cell model and analyzing relevant inflammatory factors. <p>METHODS: Rabbit lacrimal gland epithelial cells were <i>in vitro</i> isolated and cultured, and the activity and purity of primary cells were identified by cell proliferation experiment and immunofluorescence experiment. In addition, 0.5 times IC₅₀ of lipopolysaccharide LPS and TNF-α were used respectively to stimulate rabbit lacrimal gland epithelial cells and then establish two dry eye cell models. Finally, through cell proliferation experiment, ELISA and flow cytometry, the biological characteristics of these two dry eye cell models were compared. <p>RESULTS:After 12h of culture, the primary cells of lacrimal gland epithelial cells basically adhered to the wall of culture bottles; and 48h later, the cells stretched and almost each of them presented a shape of a long triangle. The activity of primary cells of lacrimal gland epithelium was 92%, and the positive rate of marker Pan-rkeratin was more than 90%, which accorded with the experimental requirements. The IC₅₀ of LPS and TNF-α are 20μg/mL and 4.996ng/mL respectively. After 12h of intervention with LPS(10μg/mL)and TNF-α(2.5ng/mL), the cell activity of the two groups was significantly lower than that of control group(<i>P</i><0.01); compared between these two groups, the apoptosis rate of TNF-α group is higher than that of LPS group(<i>P</i><0.01). The levers of IL-1β and IL-6 in the cell supernatants of the two groups were significantly higher than those of the control group(<i>P</i><0.01); compared between the two groups, IL-1β and IL-6 in TNF-α group were significantly higher than those in LPS group(<i>P</i><0.01). It was suggested that TNF-α was superior to LPS in simulating inflammatory response of dry eye. <p>CONCLUSION: This study successfully established a relatively simple and rapid rabbit dry eye cell model with high cell purity and stability, which provided a more stable <i>in vitro</i> experimental model for the basic research on the function of rabbit lacrimal gland epithelial cells and dry eye.

Advances in the evaluation of intra-tumoral delivery of antitumor drugs / 中国临床药理学与治疗学

Tumor tissue is highly heterogeneous and complex in structure. Numerous barriers make it difficult for anti-tumor drugs to reach the center of the tumor tissue, which affects the efficacy. Currently, various strategies to improve intra-tumoral drug delivery are emerging in an endless stream, but the clinical conversion efficiency is low. Hence, it is essential to improve the early evaluation system of intra-tumoral drug delivery. Reasonable evaluation of intra-tumoral drug delivery can rely on three-dimensional cell models, in-vivo imaging technology and appropriate mathematical model to comprehensively reveal the drug delivery process in tumor tissues, predict and screen various influencing factors, and feedback to guide the optimization of intra-tumoral delivery of drugs. This article reviews the evaluation methods of intra-tumoral delivery of anti-tumor drugs, aiming to evaluate the transport of anti-tumor drugs in tumor tissues more accurately and reasonably, and to provide reference and ideas for the synthesis, preparation design, drug combination and optimization of clinical drug regimen of anti-tumor drugs.

The construction of nasal cavity-mimic M-cell model, design of M cell-targeting nanoparticles and evaluation of mucosal vaccination by nasal administration

In order to better evaluate the transport effect of nanoparticles through the nasal mucosa, an nasal cavity-mimic model was designed based on M cells. The differentiation of M cells was induced by co-culture of Calu-3 and Raji cells in invert model. The ZO-1 protein staining and the transport of fluorescein sodium and dexamethasone showed that the inverted co-culture model formed a dense monolayer and possessed the transport ability. The differentiation of M cells was observed by up-regulated expression of Sialyl Lewis A antigen (SLAA) and integrin 1, and down-regulated activity of alkaline phosphatase. After targeting M cells with iRGD peptide (cRGDKGPDC), the transport of nanoparticles increased. , the co-administration of iRGD could result in the increase of nanoparticles transported to the brain through the nasal cavity after intranasal administration. In the evaluation of immune effect , the nasal administration of OVA-PLGA/iRGD led to more release of IgG, IFN-, IL-2 and secretory IgA (sIgA) compared with OVA@PLGA group. Collectively, the study constructed M cell model, and proved the enhanced effect of targeting towards M cell with iRGD on improving nasal immunity.

Establishment of a cell model for high-throughput TRPV4 regulator screening based on CaCC / 解放军医学杂志

Objective To construct a high-throughput screening model for transient receptor potential vanilloid 4 (TRPV4) channel modulators based on calcium-activated chloride channels (CaCC). Methods RT-PCR was used to detect the endogenous expression of TRPV4 in Fischer rat thyroid (FRT) cells. The PCR products obtained were subjected to nucleic acid sequencing using gel-recovery technology. Western blotting was employed to detect the expression of TRPV4 protein in FRT cells. The liposome transfection method was applied to construct the FRT cell model that co-expressed anoctamin 1 (ANO1) and YFP-H148Q/ I152L. The expressions of ANO1 and YFP-H148Q/I152L in cells were identified by the inverted fluorescence microscope and the fluorescence quenching kinetics test. After adding TRPV4 activators and inhibitors, the fluorescence quenching kinetics experiment was used to test whether the model could screen TRPV4 modulators. The Fura-2 fluorescent probe method was applied to detect the calcium concentration in cells after adding TRPV4 activators; The Z' factor was calculated to evaluate the sensitivity and specificity of the cell model. Results RT-PCR and Western blotting confirmed the endogenous expression of TRPV4 in FRT cells; ANO1 was clearly expressed on the FRT cell membrane and YFP-H148Q/I152L was clearly expressed in the cytoplasm of FRT cells under the inverted fluorescence microscope. The FRT cell model co-expressing ANO1 and YFP-H148Q/I152L was successfully constructed. Fluorescence quenching kinetics experiments confirmed that the model could screen TRPV4 regulators, and the slope value of fluorescence change and the concentration of TRPV4 regulator concentration were in a dose-dependent manner. The model could sensitively detect changes in intracellular calcium concentration, and the slope value could reflect intracellular calcium concentration. The Z' factor was 0.728, which demonstrates its capacity for high-throughput screening. Conclusions We successfully constructed a high-throughput model that could screen TRPV4 modulators sensitively and efficiently.

Effects of low molecular weight chitosan and its nanoparticles on intestinal permeability of Panax notoginseng saponins / 中草药

Objective: To evaluate the effect of low molecular weight chitosan (LMW-CTS) and its nanoparticles (LMW-CTS-NPs) on the intestinal permeability of Panax notoginseng saponins (PNS) by using Caco-2 cell model. Methods: LMW-CTS was prepared by combining chitosanase hydrolysis combined with ultrafiltration separation technology, and molecular weight of LMW-CTS was determined by using permeation gel chromatography (GPC). LMW-CTS-NPs were prepared by ionic gel method, and characterized by scanning electron microscopy, nano particle sizer, and flourier transformation infrared spectroscopy. Caco-2 cell model was established and validated to evaluate the effects of LMW-CTS and LMW-CTS-NPs on the intestinal permeability of PNS. Results: LMW-CTS has a molecular weight of 5 760 and a polydispersity coefficient of 1.42. LMW-CTS-NPs have a round shape and narrow particle size distribution, with an average particle size of 115.5 nm and zeta potential of +37.1 mV. The apparent permeability coefficients (Papp, AB→BL) of PNS was less than 1 × 10-6 cm/s, indicating a poor permeability. In LMW-CTS group, the Papp of R1 and Rg1 was increased by 17.83% and 20.29%, respectively, but no significant effect of promotion was observed on other components. However, the Papp of R1, Rg1, Re, Rb1, and Rd in LMW-CTS-NPs group was increased by 35.66%, 23.28%, 29.41%, 37.99%, and 36.00%, respectively, compared tothe control group. Conclusion: LMW-CTS can significantly promote the intestinal mucosal permeability of R1 and Rg1 in PNS, but has no significant effect on Re, Rb1, and Rd. LMW-CTS-NPs significantly increased the permeability of the major monomer saponin components in PNS. Namely, the intestinal permeability of PNS can be further improved by transforming LMW-CTS into LMW-CTS-NPs.

Influences of molecular weight and particle size to intranasal drug delivery based on cell model of "nose-brain" / 中草药

Objective: To explore the factors affecting the nasal entry of the pharmaceutical preparations into the brain based on the established model of the "nose-brain" pathway in vitro. Methods: Calu-3 cells and OECs cells were co-cultured to construct a "nasal-brain" pathway cell model group. Taking fluorescein isothiocyanate dextran (FD) and fluorescent silver nanoparticles (AgNPs) as model drugs, the effects of drug molecular weight (Mw) factors and preparation particle size factors on the drug transnasal transport into the brain were explored. Results: The apparent permeability coefficient (Papp) of transcellular monolayer transport of FD decreased with the increase of molecular weight. The uptake of fluorescein isothiocyanate dextran with different molecular weights by OECs tended to be saturated after 90 min. As the molecular weight of FD increased, the uptake of OECs decreased significantly during the same uptake time. The apparent permeability coefficient of fluorescent AgNPs with different particle sizes in the "nose-brain" multi-channel cell model group of calu-3 monolayer decreased with the increase of the particle size of the nanoparticles. When the particle size was less than 40 nm, its transport characteristics in Calu-3 were shown as medium absorption (1 × 10-6 < Papp < 10 × 10-6), and when the particle size of nanoparticles was more than 60 nm, its transport characteristics were shown as difficult to absorb (Papp < 1 × 10-6). The uptake of OECs of fluorescent AgNPs with different particle sizes tended to be saturated at 60 min, and with the increase of the particle size of fluorescent AgNPs, the uptake of OECs at the same uptake time showed a significant decline. Conclusions The Mw of the drug and the particle size of the nano-formulation have an important influence on the nasal transport of the drug into the brain. Drugs with a molecular weight of < 4 000 and nano particles with a particle size of less than 40 nm have better transport and uptake characteristics.

Determination of the bioaccessibility of cadmium and arsenic in earthworms by PBET digestion in vitro / MDCK cell model with risk assessment / 药学学报

Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the content of cadmium (Cd) and arsenic (As) in earthworms. A physiologically-based extraction test (PBET) digestion in vitro /MDCK cell model was established to investigate the bioaccessibility of Cd and As in earthworms. The hazard index (HI) method and the margin of exposure (MOE) method were used to assess the risks of the total content and the bioaccessible content of Cd and As. The results showed that the total content of Cd and As in six batches of earthworms ranged from 8.319 to 33.606 mg·kg-1 and from 0.532 to 16.412 mg·kg-1, respectively. After uptake by MDCK cells, the bioaccessibility of Cd in earthworms ranged from 10.13% to 64.16%, and the bioaccessibility of As was from 2.72% to 46.57%. The results of risk assessment showed that before uptake by MDCK cells, the MOE values of As and HI values of Cd for all batches of earthworms were greater than 1, which suggests that the risks of As are acceptable but the risks of Cd are unacceptable. After transportation by MDCK cells, except for one batch of earthworms, the HI values of Cd in the other five batches were less than 1, which suggests that the risks are at a safe level. This study provides important technical support for a more objective and scientific assessment of the health risks of heavy metals in traditional Chinese medicines, and for a more scientific and reasonable standard limit of heavy metals.

Application of three-dimensional cell model in tumor research / 中国药科大学学报

@#The three-dimensional cell model cultures different types of cells in vitro. By means of special materials or carriers, the cells can grow, migrate and differentiate in a three-dimensional environment. The three-dimensional cell model provides the cells with an in vitro environment that is close to in vivo, making the gene expression and signal exchange of the cells more physiologically relevant. This paper starts with the concept and classification of three-dimensional cell model, then summarizes the applications and progresses of three-dimensional cell model in tumor micro-environment, cancer metastasis and anti-tumor drug development in recent years. Based on the current shortcomings of the three-dimensional cell model, this paper presents the assumptions and prospects for the application of three-dimensional cell model in tumor therapy.

The Protozoan Tetrahymena: Cellular Model for Biological Studies

Biological research, including clinical trials, mainly uses animals as model organisms. Currently, animal experimentation remains controversial for several reasons, namely the implementation of animal protection and ethics panels, the high costs and the long duration of experiments. These constraints encourage researchers to use alternative methods in order to overcome these barriers. The ciliate Tetrahymena is a unicellular eukaryotic organism that has contributed significantly to the acquisition of knowledge in the field of fundamental biology. Characterised by a well-ordered structure and a short life cycle, the protozoan Tetrahymena is very commonly used in the laboratory due to the ease involved in handling it. Therefore, this organism has allowed researchers to elucidate a number of mechanisms in higher organisms including mammals. This bibliographic review describes the favourable biological characteristics of the protozoan Tetrahymena as well as various physiological and molecular studies that have been carried out on this organism. Studies have shown that Tetrahymena is one of the alternatives to animal experimentation and a major contributor to the development of biological and life sciences.

Decellularized matrix of human fatty liver used for three-dimensional culture of hepatocellular carcinoma cells / 南方医科大学学报

OBJECTIVE@#To construct a decellularized matrix of human fatty liver as the scaffold for three-dimensional (3D) culture of hepatocarcinoma cells.@*METHODS@#Human fatty liver decellularized matrix (hFLM) was prepared by repeated freezingthawing, perfusion with gradient SDS and 1% Triton X-100 through the portal vein and hepatic artery, and repeated agitation with Triton X-100. HepG2 cells were cultured in the prepared hFLM, and the cell survival, morphology, proliferation and cellular expressions of the adhesion molecules were detected.@*RESULTS@#The decellularization procedure shortened the time for scaffold preparation and preserved the 3D ultrastructure and the composition of the extracellular matrix. HepG2 cells cultured in hFLM scaffold maintained proliferation for up to 15 days and showed a growth pattern with a long lag phase and a slow growth rate, which was similar to the growth pattern . The cultured HepG2 exhibited a low expression of E-cadherin and a high expression of vimentin, which was consistent with the xenograft but opposite to 2D cultured cells. However, the lack of adequate nutrient transport in this hepatocarcinoma cell model led to a slowdown of cell proliferation in the later stage. The PCNA index of HepG2 cells cultured in hFLM was lowered by 29.3% on day 12 as compared with that on day 6.@*CONCLUSIONS@#We established a new protocol for preparing hFLM and confirmed the feasibility of constructing hepatocarcinoma cell models using the hFLM scaffold.

Classification and research prospect ofin vitro andin vivomodels of psoriasis / 中国组织工程研究

BACKGROUND: In vivo and in vitro models of psoriasis are an important way to understand the pathogenesis. Although existing animal models can partially simulate the pathological manifestations of psoriasis, they are not representative. OBJECTIVE: To summarize the classification and research progress of animal and cell models of psoriasis, and to provide beneficial references for researchers to select appropriate models of psoriasis. METHODS: PubMed, CNKI and WanFang databases were retrieved with the keywords of “psoriasis and animal model” in English and Chinese, respectively. After screening the literature, 51 eligible articles were finally included. RESULTS AND CONCLUSION: According to the animal modeling method, the literature included in the study was summarized. The animal models used for psoriasis included genetic engineering mouse model, spontaneous psoriasis mouse model, exogenous induced psoriasis model, xenotransplantation model and traditional Chinese medicine disease-syndrome combination animal model. All kinds of animal models of psoriasis simulate the pathological manifestations of psoriasis to a certain extent, but there are still limitations of differences in pathogenesis and species. Cell models can reveal changes in biological behaviors and interactions of keratinocytes or other cell types in psoriasis. Researchers can choose the most suitable model of psoriasis in vivo and in vitro according to their research purposes and experimental condition.