OBJECTIVETo observe the effect of SIRT1 on intestinal barrier function of epithelial Caco-2 cells under hypoxia and investigate its mechanism.

METHODSCaco-2 cells were randomly divided into three groups: normoxia group (Nx), hypoxia group (Hx,1%O2 for 6 h) and hypoxia plus 40 μmol/L Resveratrol (agonist of SIRT1) group (Hx+Res). Transepithelial electrical resistance (TER) was determined. mRNA and protein expressions of SIRT1 and tight junctions (ZO-1, Occludin, Claudin-1) were examined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting.

RESULTSBoth mRNA and protein expressions of SIRT1 were significantly reduced in Hx group as compared with Nx group (0.40±0.02 vs. 0.70±0.07, P=0.001; 0.37±0.03 vs. 0.76±0.03, P=0.001). The mRNA and protein expressions of SIRT1 were significantly increased in Hx+Res group as compared with Hx group(0.50±0.02 vs. 0.40±0.02, P=0.026; 0.54±0.02 vs. 0.37±0.03, P=0.011). The expression levels of ZO-1, Occludin and Claudin-1 in Hx group were lower than those in Nx group (P<0.05), however, pretreatment with Resveratrol could attenuate the decreased expression of above 3 molecules under hypoxia(P<0.05). TERs of Nx group, Hx group and Hx+Res group were (142±7) Ohm/cm(2), (94±3) Ohm/cm(2) and (119±7) Ohm/cm(2) respectively. Compare with the Nx group, the TER of Hx group was significantly decreased(P<0.05). TER of Hx+Res group was significantly increased compare with Hx group, but it was still significantly lower than that in Nx group(P<0.05).

CONCLUSIONSExpression of SIRT1 is significantly reduced under hypoxia. Activation of SIRT1 can maintain the epithelial barrier function through regulating the expression of tight junctions under hypoxia.

Caco-2 Cells ; Cell Hypoxia ; Claudin-1 ; metabolism ; Epithelial Cells ; metabolism ; Humans ; Intestinal Mucosa ; cytology ; Occludin ; metabolism ; Sirtuin 1 ; metabolism ; Zonula Occludens-1 Protein ; metabolism

OBJECTIVETo study on the expression patterns of proteins associated with cell junctions in the developing mouse testes.

METHODThe expression levels of reproductive related cell lines spermatogonia cell line GC1 spg, spermatocyte cell line GC2 spg, leydig cell line TM3, and sertoli cell line TM4, primary sertoli cells, and 1-6-week mouse testes were analyzed using Western blot.

RESULTSThe sertoli cell junction-associated membrane proteins adhesion molecule A, Occludin and Claudin, and the sertoli-germ cell junction-associated membrane proteins junctional adhesion molecule C, Nectin-3, and E-cadherin were stage-specific in the seminiferous tubules in the mouse testes. The adaptor proteins associated with cell juctions zonula occludens-1, zonula occludens-2, Afadin, Β-catenin, and CD2-associated protein were not stage-specific in the seminiferous tubules in the mouse testes.

CONCLUSIONSIn the seminiferous tubules in the mouse testes, the membrane proteins associated with cell junctions are stage-specific. However, the expressions of adaptor proteins associated with cell junctions do not obviously change.

Adaptor Proteins, Signal Transducing ; metabolism ; Animals ; Cdh1 Proteins ; metabolism ; Cell Adhesion Molecules ; metabolism ; Cell Line ; Cytoskeletal Proteins ; metabolism ; Humans ; Intercellular Junctions ; metabolism ; Male ; Membrane Proteins ; metabolism ; Mice ; Microfilament Proteins ; metabolism ; Nectins ; Seminiferous Tubules ; cytology ; metabolism ; Sertoli Cells ; cytology ; Testis ; cytology ; Zonula Occludens-1 Protein ; metabolism ; Zonula Occludens-2 Protein ; metabolism ; beta Catenin ; metabolism

OBJECTIVETo study the effect of hypoxia on Slingshot protein expression in human intestinal epithelial cell and its relation with changes in barrier function of the cells.

METHODSThe human intestinal epithelial cell line Caco-2 was used to reproduce monolayer-cells. One portion of the monolayer-cell specimens were divided into six parts according to the random number table, and they were respectively exposed to hypoxia for 0 (without hypoxia), 1, 2, 6, 12, and 24 h. Transepithelial electrical resistance (TER) was determined with an ohmmeter. Another portion of the monolayer-cell specimens were exposed to hypoxia as above. Western blotting was used to detect the protein expressions of zonula occludens 1 (ZO-1), occludin, claudin-1, Slingshot-1, Slingshot-2, and Slingshot-3. The remaining portion of the monolayer-cell specimens were also exposed to hypoxia as above. The content of fibrous actin (F-actin) and globular actin (G-actin) was determined by fluorescence method. The sample number of above-mentioned 3 experiments was respectively 10, 10, and 18 at each time point. Data were processed with one-way analysis of variance and Dunnett test.

RESULTS(1) Compared with that of cells exposed to hypoxia for 0 h, TER of cells exposed to hypoxia for 1 to 24 h was significantly reduced (P values below 0.01). (2) Compared with those of cells exposed to hypoxia for 0 h (all were 1.00), the protein expressions of ZO-1, occludin, and claudin-1 of cells exposed to hypoxia for 1 to 24 h were generally lower, especially those of cells exposed to hypoxia for 12 h or 24 h (respectively 0.69 ± 0.20, 0.47 ± 0.15, and 0.47 ± 0.22, P<0.05 or P<0.01). Compared with those of cells exposed to hypoxia for 0 h, the protein expressions of Slingshot-1 and Slingshot-3 of cells exposed to hypoxia for 1 to 24 h were not obviously changed (P values above 0.05). The protein expression of Slingshot-2 of cells was decreased at first and then gradually increased from hypoxia hour 1 to 24. The protein expression of Slingshot-2 of cells exposed to hypoxia for 24 h (1.54 ± 0.57) was significantly higher than that of cells exposed to hypoxia for 0 h (1.00, P<0.05). (3) Compared with those of cells exposed to hypoxia for 0 h, the content of F-actin of cells exposed to hypoxia for 1, 6, 12, and 24 h was significantly decreased, whereas the content of G-actin of cells exposed to hypoxia for 6-24 h was significantly increased, P<0.05 or P<0.01; the content of F-actin and G-actin of cells exposed to hypoxia for the other time points was not obviously changed (P values above 0.05).

CONCLUSIONSHypoxia may cause cofilin activation after dephosphorylation and the depolymerization of F-actin by inducing Slingshot-2 protein expression, which in turn affects the tight junction of human intestinal epithelial cells, thus leading to deterioration of barrier function of these cells.

Actins ; metabolism ; Blotting, Western ; Caco-2 Cells ; Cell Hypoxia ; Claudin-1 ; metabolism ; Epithelial Cells ; cytology ; metabolism ; Humans ; Intestines ; cytology ; Occludin ; metabolism ; Phosphoprotein Phosphatases ; metabolism ; Tight Junctions ; metabolism ; Zonula Occludens-1 Protein ; metabolism

OBJECTIVETo study the effect of hypoxia on cofilin activation in intestinal epithelial cells and its relation with distribution of tight junction protein zonula occludens 1 (ZO-1).

METHODSThe human intestinal epithelial cell line Caco-2 was used to reproduce monolayer cells. The monolayer-cell specimens were divided into control group (no treatment), hypoxic group ( exposed to hypoxia), and normoxic group (exposed to normoxia) according to the random number table. Western blotting was used to detect the protein expressions of cofilin and phosphorylatedl cofilin (p-cofilin) of cells in normoxic group and hypoxic group exposed to normoxia or hypoxia for 1, 2, 6, 12, and 24 h and control group, with 9 samples in control group and 9 samples at each time point in the other two groups. The other monolayer-cell specimens were divided into hypoxic group (exposed to hypoxia) and control group (no treatment) according to the random number table. Cells in hypoxic group exposed to hypoxia for 1, 2, 6, 12, and 24 h and control group were obtained. Morphology and distribution of F-actin was observd with laser scanning confocal microscopy, the ratio of F-actin to G-actin was determined by fluorescence method, and distribution of ZO-l and cellular morphology were observed with laser scanning confocal microscopy. The sample number of last 3 experiments was respectively 3, 6, and 3 in both hypoxic group (at each time point) and control group. Data were processed with paired ttest, analysis of variance of repeated measurement, and LSD-t test.

RESULTSThe protein expressions of cofilin and p-cofilin of cells between normoxic group exposed to normoxia for 1 to 24 h and control group showed no significant changes (with values from -0.385 to 1.701, t(p-cofilin)values from 0. 040 to 1.538, P values above 0.05). There were no obvious differences in protein expressions of en filmn of cells between hypoxic group exposed to hypoxia for 1 to 24 h and control group ( with values from 1.032 to 2.390, P values above 0.05). Compared with that in control group, the protein expressions of p-cofilin of cells were greatly reduced in hypoxic group exposed to hypoxia for 1 to 24 h (with values from 4.563 to 22.678, P values below 0.01), especially exposed to hypoxia for 24 h. The protein expressions of cofilin of cells between normoxic group and hypoxic group at each time point were close ( with t values from -0.904 to 1.433, P values above 0.05). In hypoxic group, the protein expressions of p-cofilin of cells exposed to hypoxia for 1, 2, 6, 12, and 24 h were 0.87 +/- 08, 0.780 .05, 0.89 +/- 0.07, 0.68+0. 07, and 0.57 +/- 0.06, respectively, significantly lower than those in normoxic group (0.90 +/- 0.07, 0.97 +/- 0.06, 1.00 +/- 0.06, 1.00 +/- 0.05, and 0.99 +/- 0.05, with t values from 3.193 to 16.434, P values below 0.01). In control group, F-actin in the cytoplasm was abundant, most of it was in bunches. The trend of F-actin was disorderly in hypoxic group from being exposed to hypoxia for 1 h, shortened in length or even dissipated. The ratios of F-actin to G-actin of cells in hypoxic group exposed to hypoxia for 12 and 24 h (0.89 +/- 0.12 and 0.84 +/- 0.19) were obviously decreased as compared with that in control group (1. 00, with t values respectively 3. 622 and 3. 577, P values below 0.01). There were no obvious differences in the ratios of F-actin to G-actin of cells between hypoxic group exposed to hypoxia for 1, 2, and 6 h and control group ( with values from 0.447 to 1.526, P values above 0.05). In control group, cells were compact in arrangement, and ZO-1 was distributed continuously along the cytomnembrane. From being exposed to hypoxia for 2 h, cells became irregular in shape in hypoxic group. ZO-1 was distributed in discontinuous fashion along the cytomembrane with breakage in hypoxic group exposed to hypoxia for 24 h.

CONCLUSIONSHypoxia may cause the disorder of dynamic balance between F-actin and G-actin by inducing cofilin activation, which in turn leads to the changes in distribution of tight junction protein ZO-1 in intestinal epithelial cells.

Actin Depolymerizing Factors ; Actins ; Blotting, Western ; Caco-2 Cells ; drug effects ; physiology ; Epithelial Cells ; cytology ; drug effects ; Humans ; Hypoxia ; metabolism ; Intestinal Mucosa ; drug effects ; metabolism ; pathology ; Intestines ; Oxygen ; pharmacology ; Tight Junctions ; drug effects ; metabolism ; Zonula Occludens-1 Protein ; metabolism

BACKGROUNDThere are more than 300 genetic loci that have been found to be related to hereditary hearing impairment (HHI), including 92 causative genes for nonsyndromic hearing loss, among which 34 genes are related to autosomal dominant nonsyndromic HHI (ADNSHHI). Traditional linkage analysis and candidate gene sequencing are not effective at detecting the ADNSHHI, especially for the unconditional families that may have more than one pathogenic cause. This study identified two disease-causing genes TJP2 and GJB2 in a Chinese family with unconditional ADNSHHI.

METHODSTo decipher the genetic code of a Chinese family (family 686) with ADNSHHI, different gene screening techniques have been performed, including linkage analysis, candidate genes screening, high-throughput sequencing and Sanger sequencing. These techniques were done on samples obtained from this family over a period of 10 years.

RESULTSWe identified a pathogenic missense mutation, c. 2081G>A (p.G694E), in TJP2, a gene that plays a crucial role in apoptosis and age-related hearing loss (ARHL). The mutation was co-segregated in this pedigree in all, but not in the two patients who presented with different phenotypes from the other affected family members. In one of the two patients, we confirmed that the compound heterozygosity for p.Y136* and p.G45E in the GJB2 gene may account for the phenotype shown in this patient.

CONCLUSIONSWe identified the co-occurrence of two genetic causes in family 686. The possible disease-causing missense mutation of TJP2 in family 686 presents an opportunity for further investigation into ARHL. It is necessary to combine various genes screening methods, especially for some unconventional cases.

Adult ; Aged ; Asian Continental Ancestry Group ; Connexins ; genetics ; Exome ; genetics ; Female ; Genetic Linkage ; genetics ; Haplotypes ; genetics ; Hearing Loss, Sensorineural ; genetics ; Humans ; Male ; Middle Aged ; Mutation ; genetics ; Pedigree ; Young Adult ; Zonula Occludens-2 Protein ; genetics

OBJECTIVETo investigate the change in the expression of tight junction protein ZO-1 in intestinal epithelial cells (Caco-2 cells) and the protective effect of eicosapentaenoic acid (EPA) after adherent-invasive Escherichia coli (E.coli) LF82 infection.

METHODSThe Caco-2 cell line was used to establish an in vitro model of tight junction of intestinal epithelial cells. Caco-2 cells were divided into EPA treatment groups (0, 25, 50, 100, and 200 μmol/L EPA) and EPA (0, 25, 50, 100, and 200 μmol/L EPA)+E.coli LF82 treatment (0, 6, and 12 hours) groups. A microscope was used to observe the morphological characteristics of the cells. MTT assay was used to determine the cell growth curve. The activity of alkaline phosphatase (ALP) at both sides of the cell membrane was compared to evaluate the Caco-2 cell model. MTT assay and flow cytometry were used to investigate the effects of different concentrations of EPA on the survival rate and apoptosis rate of Caco-2 cells. RT-qPCR was used to measure the mRNA expression of ZO-1 in Caco-2 cells after EPA and/or E.coli LF82 treatment. ELISA was used to measure the change in the level of tumor necrosis factor-α (TNF-α) in culture supernatant.

RESULTSAfter EPA treatment (25 and 50 μmol/L), the proliferation of Caco-2 cells was induced in a dose-dependent manner. The survival rates of the cells were significantly higher than those in the control group (P<0.05). The EPA treatment (100 and 200 μmol/L) groups had a significant inhibitory effect on the proliferation of Caco-2 cells in a dose-dependent manner. The survival rates of the cells were significantly lower than those in the control group (P<0.05). The EPA treatment (100 and 200 μmol/L) groups had a significant increase in cell apoptosis rate compared with the control group (P<0.05). The 6- and 12-hour E.coli LF82 treatment groups had decreasing mRNA expression of ZO-1 in Caco-2 cells over the time of treatment and had significantly lower mRNA expression of ZO-1 than the untreated group (P<0.05). The Caco-2 cells treated with E.coli LF82 and 25 or 50 μmol/L EPA for 6 or 12 hours showed an increase in the mRNA expression of ZO-1 with the increasing concentration of EPA, as well as significantly higher mRNA expression of ZO-1 than the Caco-2 cells treated with E.coli LF82 alone (P<0.05). The Caco-2 cells treated with E.coli LF82 alone for 6 or 12 hours had increasing secretion of TNF-α over the time of treatment and had significantly higher secretion than the untreated Caco-2 cells (P<0.05). The Caco-2 cells treated with E.coli LF82 and 25 or 50 μmol/L EPA for 6 or 12 hours showed a reduction in the secretion of TNF-α with the increasing concentration of EPA and had significantly lower secretion than the Caco-2 cells treated with E.coli LF82 alone (P<0.05).

CONCLUSIONSEPA can effectively prevent the destruction of tight junction of intestinal epithelial cells induced by E.coli LF82 infection and inhibit the secretion of inflammatory factors. Therefore, it has a certain protective effect on intestinal mucosal barrier.

Apoptosis ; drug effects ; Caco-2 Cells ; Eicosapentaenoic Acid ; pharmacology ; Escherichia coli ; pathogenicity ; Humans ; Intestinal Mucosa ; metabolism ; microbiology ; RNA, Messenger ; analysis ; Tight Junctions ; drug effects ; Tumor Necrosis Factor-alpha ; secretion ; Zonula Occludens-1 Protein ; genetics

OBJECTIVETo investigate the effect of ceftriaxone on the intestinal epithelium and microbiota in mice in the early-life stage, as well as the recovery of the intestinal epithelium and reconstruction of intestinal microbiota in adult mice.

METHODSA total of 36 BALB/C neonatal mice were randomly divided into control group and experimental group, with 18 mice in each group. The mice in the experimental group were given ceftriaxone 100 mg/kg every day by gavage within 21 days after birth. Those in the control group were given an equal volume of normal saline by gavage. Immunohistochemistry was used to measure the expression of Ki67, Muc2, and ZO-1 in the intestinal epithelium. qPCR and next-generation sequencing were used to analyze the overall concentration and composition of fecal bacteria.

RESULTSAfter 21 days of ceftriaxone intervention, the experimental group had a significant reduction in body weight, a significant reduction in the expression of Ki67 and ZO-1 and a significant increase in the expression of Muc2 in intestinal epithelial cells, a significant reduction in the overall concentration of fecal bacteria, and a significant increase in the diversity of fecal bacteria compared with the control group (P<0.05). Firmicutes was the most common type of fecal bacteria in the experimental group, and there were large amounts of Staphylococcus and Enterococcus. The experimental group had a certain degree of recovery of the intestinal epithelium, but there were still significant differences in body weight and the structure of intestinal microbiota between the two groups at 56 days after birth (P<0.05).

CONCLUSIONSEarly ceftriaxone intervention significantly affects the development of the intestinal epithelium and the construction of intestinal microbiota in the early-life stage. The injury of the intestinal microbiota in the early-life stage may continue to the adult stage and affect growth and development and physiological metabolism.

Animals ; Animals, Newborn ; Anti-Bacterial Agents ; pharmacology ; Ceftriaxone ; pharmacology ; Female ; Gastrointestinal Microbiome ; drug effects ; Intestinal Mucosa ; drug effects ; Ki-67 Antigen ; analysis ; Mice ; Mice, Inbred BALB C ; Mucin-2 ; analysis ; Zonula Occludens-1 Protein ; analysis

Objective: To explore the role of TGF-β1 in the proliferation and apoptosis of Sertoli cells and its effect on the expressions of tight junction-related proteins and genes in rats. METHODS: Rat Sertoli cells were isolated in vitro, primarily cultured, and divided into groups A (blank control), B (TGF-β1 receptor blocker), C (TGF-β1), and D (TGF-β1 + receptor blocker). The proliferation and apoptosis of the cells were detected by CCK-8 and flow cytometry, respectively. After establishment of the dual-chamber model for the primary culture of Sertoli cells, the trans-epithelia electrical resistance (TER) value was measured and the relative expressions of Occludin, ZO-1 and Claudin Ⅱ determined by RT-PCR and Western blot. RESULTS: The OD value of the proliferation of the Sertoli cells was markedly higher in group C than in groups A and D (0.79 ± 0.04 vs 0.66 ± 0.05 and 0.68 ± 0.02, P<0.05), with statistically significant differences among the four groups (F = 5.05, P <0.05). However, no remarkable difference with found among the four groups in the apoptosis rate of the cells (F = 1.13, P >0.05). The TER value was dramatically decreased in group C as compared with groups A and D (［176.37 ± 16.61］ vs ［281.42 ± 9.83］ and ［254.37 ± 13.55］ /cm2, P<0.01), with statistically significant differences among the four groups (F = 38.99, P<0.01). There were no remarkable differences among the four groups in the mRNA expressions of ZO-1 and Claudin Ⅱ (F = 0.49 and 0.93, P>0.05) or their protein expressions (F = 0.28 and 1.31, P>0.05). Both the mRNA and protein expressions of Occludin were markedly lower in group C than in A and D (P<0.01 and P<0.05), with statistically significant differences among the four groups (F = 6.86 and 6.87, P<0.01). CONCLUSIONS TGF-β1 can promote the proliferation of Sertoli cells in rats and act on the tight junction of the cells by regulating the expression of Occludin.
Animals ; Apoptosis ; Cell Proliferation ; Cells, Cultured ; Claudin-2 ; metabolism ; Male ; Occludin ; metabolism ; RNA, Messenger ; Rats ; Sertoli Cells ; cytology ; physiology ; Tight Junction Proteins ; metabolism ; Tight Junctions ; genetics ; metabolism ; Transforming Growth Factor beta1 ; physiology ; Zonula Occludens-1 Protein ; metabolism

Objective: To investigate the effect of nuclear factor erythroid 2-related factor 2 (Nrf2) in the alteration of tight junction protein expression in choroid plexus epithelial cells created by lanthanum-activated matrix metalloproteinase 9 (MMP9) . Methods: In October 2020, immortalized rat choroid plexus epithelial cell line (Z310) cells were used as the blood-cerebrospinal fluid barrier in vitro, and were divided into control group and 0.125, 0.25, 0.5 mmol/L lanthanum chloride (LaCl(3)) treatment group. After treating Z310 cells with different concentrations of LaCl(3) for 24 hours, the morphological changes of Z310 cells were observed under inverted microscope, the protein expression levels of MMP9, occludin and zonula occludens-1 (ZO-1) were observed by cellular immunofluorescence method, and the protein expression levels of MMP9, tissue inhibitors of metalloproteinase1 (TIMP1) , occludin, ZO-1 and Nrf2 were detected by Western blotting. The level of reactive oxygen species (ROS) in cells was detected by flow cytometry. Results: Compared with the control group, Z310 cells in the LaCl(3) treatment group were smaller in size, with fewer intercellular junctions, and more dead cells and cell fragments. The expression level of MMP9 protein in cells treated with 0.25 and 0.5 mmol/L LaCl(3) was significantly higher than that in the control group (P<0.05) , and the expression level of TIMP1 and tight junction proteins occudin and ZO-1 was significantly lower than that in the control group (P<0.05) . Compared with the control group, the ROS production level in the 0.25, 0.5 mmol/L LaCl(3) treatment group was significantly increased (P<0.05) , and the Nrf2 protein expression level in the 0.125, 0.25, 0.5 mmol/L LaCl(3) treatment group was significantly decreased (P<0.05) . Conclusion: Lanthanum may increase the level of ROS in cells by down regulating the expression of Nrf2, thus activating MMP9 to reduce the expression level of intercellular tight junction proteins occludin and ZO-1.
Rats ; Animals ; Matrix Metalloproteinase 9/metabolism* ; NF-E2-Related Factor 2/metabolism* ; Tight Junction Proteins/metabolism* ; Occludin/pharmacology* ; Choroid Plexus/metabolism* ; Reactive Oxygen Species/metabolism* ; Lanthanum/pharmacology* ; Epithelial Cells ; Zonula Occludens-1 Protein/metabolism* ; Phosphoproteins/pharmacology*

The present study is to establish Caco-2/HT29-MTX co-cultured cells and investigate the transport capability of PLGA nanoparticles with different surface chemical properties across Caco-2/HT29-MTX co-cultured cells. PLGA-NPs, mPEG-PLGA-NPs and chitosan coated PLGA-NPs were prepared by nanoprecipitation method using poly(lactic-co-glycolic acid) as carrier material with surface modified by methoxy poly(ethylene glycol) and chitosan. The particle size and zeta potential of nanoparticles were measured by dynamic light scattering. Coumarin 6 was used as a fluorescent marker in the transport of nanoparticles investigated by confocal laser scanning microscopy. The transport of furanodiene (FDE) loaded nanoparticles was quantitively determined by high performance liquid chromatography. Colchicine and nocodazole were used in the transport study to explore the involved endocytosis mechanisms of nanoparticles. Distribution of the tight junction proteins ZO-1 was also analyzed by immunofluorescence staining. The results showed that the nanoparticles dispersed uniformly. The zeta potential of PLGA-NPs was negative, the mPEG-PLGA-NPs was close to neutral and the CS-PLGA-NPs was positive. The entrapment efficiency of FDE in all nanoparticles was higher than 75%. The transport capability of mPEG-PLGA-NPs across Caco-2/HT29-MTX co-cultured cells was higher than that of PLGA-NPs and CS-PLGA-NPs. Colchicine and nocodazole could significantly decrease the transport amount of nanoparticles. mPEG-PLGA-NPs could obviously reduce the distribution of ZO-1 protein than PLGA-NPs and CS-PLGA-NPs. The transport mechanism of PLGA-NPs and mPEG-PLGA-NPs were indicated to be a combination of endocytosis and paracellular way, while CS-PLGA-NPs mainly relied on the endocytosis way. PEG coating could shield the surface charge and enhance the hydrophilicity of PLGA nanoparticles, which leads mPEG-PLGA-NPs to possess higher anti-adhesion activity. As a result, mPEG-PLGA-NPs could penetrate the mucus layer rapidly and transport across Caco-2/HT29-MTX co-cultured cells.
Biological Transport ; Caco-2 Cells ; Chitosan ; chemistry ; Coated Materials, Biocompatible ; chemistry ; Coculture Techniques ; Drug Carriers ; Furans ; administration & dosage ; chemistry ; metabolism ; HT29 Cells ; Heterocyclic Compounds, 2-Ring ; administration & dosage ; chemistry ; metabolism ; Humans ; Lactic Acid ; chemistry ; Nanoparticles ; Particle Size ; Polyethylene Glycols ; chemistry ; Polyglycolic Acid ; chemistry ; Zonula Occludens-1 Protein ; metabolism