The strong antioxidant activities of green tea catechins are shown to exert protective effects against chronic diseases. However, poor chemical stability and low oral bioavailability limits its usage ...as a potent nutraceutical. Hence, the objective of this study was to investigate the effect of nanoencapsulation on the physicochemical stability, in-vitro bioaccessibility and epithelial permeability of green tea catechins. Soy protein stabilized nanoemulsions containing 0.3 or 0.5 wt% green tea catechins were prepared and stability under different storage conditions (4 ± 1 °C, 28 ± 2 °C, 40 ± 1 °C) was assessed for a period of 15–20 days. At refrigeration temperature, the nanoemulsion containing 10% oil and 0.5% catechins was stable against creaming, phase separation, sedimentation and changes in droplet size, pH and catechin content. There was an observed 2.78 fold increase in the bioaccessibility of major catechins in the nanoemulsified form compared to unencapsulated catechins. Further, there was a significant increase in intestinal permeability of catechins as assessed by Caco-2 cell model. The results indicate the ability of soy protein based nanoemulsions to improve the stability, bioaccessibility and permeability of green tea catechins.
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•Catechins were nanoencapsulated in soy protein stabilized O/W nanoemulsions.•Catechin nanoemulsions had diameters ranging from 240 nm to 270 nm.•Physical stability of nanoemulsions was higher when stored at 4 °C than at 40 °C.•More than 80% of major catechins were retained after 15 days of storage at 4 ± 1 °C.•Enhanced bioaccessibility and permeability of catechins in nanoemulsions than in free form.
Bovine milk contains bioactive components that are nutritionally and immunologically important to calves and humans. Dairy cows classified as high (H) immune responders using the patented high immune ...response technology have higher concentrations of immunoglobulin and specific antibodies in sera and milk compared with average (A) and low (L) responders. MicroRNA post-transcriptionally regulate expression of milk bioactive components and are enriched in extracellular vesicles known as exosomes, which protect them from degradation. The bioactivity of colostrum and milk exosomes at the human intestinal epithelial barrier remains to be explored, particularly in the context of the high immune response technology. Therefore, the purpose of this study was to evaluate the functional role of bovine milk exosomes compared with colostrum exosomes from H, A, and L responders at the intestinal interface using human colorectal adenocarcinoma epithelial (Caco-2) cells. Exosomes were isolated by successive ultracentrifugation and confirmed by western blot analysis for the presence of common exosomal proteins (CD9, CD63, and heat shock protein 70). Fluorescent labeling of exosomes using PKH67 dye confirmed their uptake by Caco-2 cells, demonstrating their potential bioavailability. The MTT assays showed that colostrum and milk exosomes maintain Caco-2 metabolic activity and are not cytotoxic to these cells. Specifically, metabolic activity after co-incubation with colostrum and milk exosomes from H responder cows was significantly greater than after co-incubation with exosomes from L responders. Caspase 3 activity, an indicator of apoptosis, was significantly lower after co-incubation of Caco-2 cells with milk exosomes compared with colostrum exosomes, suggesting that unlike colostrum exosomes, particularly those from L responders, milk exosomes do not activate the caspase 3 pathway in Caco-2 cells. This study helps us better understand the functional importance of colostrum and milk exosomes from dairy cows and emphasizes differences in functionality among exosomes from H, A, and L immune responders.
The human colorectal adenocarcinoma cell line Caco-2, widely used for studying intestinal drug permeability, is typically grown on permeable filter supports and matures in 21 days with frequent media ...changes. The process is labor-intensive, prone to contamination, and has low throughput, contributing to the overall high utilization cost. Efforts to establish a low-cost, high-throughput, short-duration model have encountered obstacles, such as weaker tight junctions causing monolayer leaks, incomplete differentiation resulting in low transporter expression, intricate and challenging protocols, and cytotoxicity, limiting the usability. Hence, this study aimed to develop a low-cost, efficient, and short-duration model by addressing the aforementioned concerns by customizing the media and finding a safe differentiation inducer. We generated a new rapid model using sodium valerate, which demonstrated sufficient transporter activity, improved monolayer integrity, and higher levels of differentiation markers than the 21-day model. Furthermore, this model exhibited consistent and reliable results when used to evaluate drug permeability over multiple days of repeated use. This study demonstrates the potential of a sodium valerate-assisted abbreviated model for drug permeability assessment with economic and practical advantages.The human colorectal adenocarcinoma cell line Caco-2, widely used for studying intestinal drug permeability, is typically grown on permeable filter supports and matures in 21 days with frequent media changes. The process is labor-intensive, prone to contamination, and has low throughput, contributing to the overall high utilization cost. Efforts to establish a low-cost, high-throughput, short-duration model have encountered obstacles, such as weaker tight junctions causing monolayer leaks, incomplete differentiation resulting in low transporter expression, intricate and challenging protocols, and cytotoxicity, limiting the usability. Hence, this study aimed to develop a low-cost, efficient, and short-duration model by addressing the aforementioned concerns by customizing the media and finding a safe differentiation inducer. We generated a new rapid model using sodium valerate, which demonstrated sufficient transporter activity, improved monolayer integrity, and higher levels of differentiation markers than the 21-day model. Furthermore, this model exhibited consistent and reliable results when used to evaluate drug permeability over multiple days of repeated use. This study demonstrates the potential of a sodium valerate-assisted abbreviated model for drug permeability assessment with economic and practical advantages.
Fermented barley extract P (FBEP) prepared from barley shochu distillation by-product has been reported to lower serum uric acid (UA) by increasing urinary excretion of UA. ATP-binding cassette ...subfamily G member 2 (ABCG2) is a transporter responsible for UA efflux from the intestinal tract and kidneys. This study aimed to identify, among the compounds isolated from FBEP using high-performance liquid chromatography, the components that promote ABCG2 expression in Caco-2 cells. Pyroglutamylproline (pEP) increased the expression of ABCG2 in Caco-2 cells at the gene and protein levels. These results suggest that the pEP contained in FBEP may decrease serum UA levels by increasing the expression of urate efflux transporters in the intestinal epithelium and promoting UA excretion.
The intestinal epithelium is formed by a single layer of cells. These cells originate from self-renewal stem cells that give rise to various lineages of cells: Paneth, transit-amplifying, and fully ...differentiated cells (as enteroendocrine, goblet cells, and enterocytes). Enterocytes, also known as absorptive epithelial cells, are the most abundant cell type in the gut. Enterocytes have the potential to polarize as well as form tight junctions with neighbor cells which altogether serve to ensure both the absorption of "good" substances into the body and the blockage of "bad" substances, among other functions. Culture cell models such as the Caco-2 cell line have been proved to be valuable tools to study the fascinating functions of the intestine. In this chapter we outline some experimental procedures to grow, differentiate, and stain intestinal Caco-2 cells, as well as image them using two modes of confocal laser scanning microscopy.
Intestinal epithelial cells form a barrier between the intestinal lumen and host connective tissues and play an important role in maintaining intestinal nutrient homeostasis. This study investigated ...effects of Allomyrina dichotoma (rhinoceros beetle) larval extract (ADLE) on the intestinal barrier damage and explored mechanisms for reversing intestinal barrier dysfunction in lipopolysaccharide (LPS)-stimulated Caco-2, human intestinal epithelial cells. LPS reduced intestinal epithelial barrier function by increasing transepithelial electrical resistance, and this effect was significantly attenuated by ADLE treatment. ADLE also significantly countered the inhibition of tight junction-related protein expression in both LPS-induced Caco-2 cells and intestine from HFD-induced mice. Moreover, ADLE significantly decreased expression and production of inflammatory factors, such as iNOS, cox-2, nitric oxide, and cytokines induced by LPS stimulus. Reduction in phosphorylation of adenosine monophosphate-activated protein kinase was averted by ADLE treatment in LPS treated INS-1 cells. Finally, reactive oxygen stress level was decreased and ATP production was increased by ADLE treatment. ADLE appears to display gut health-promoting effects by reducing inflammation and inducing tight junction proteins in Caco-2 cells. Therefore, ADLE might be useful for preventing or treating intestine cell damage in inflammatory bowel disease.
•ADLE enhances intestinal permeability in LPS-induced Caco-2 cells.•ADLE regulates the expression of tight junction protein in LPS-induced Caco-2 cells.•ADLE reduces ROS production and increases ATP levels in LPS- induced Caco-2 cells.•ADLE displays anti-inflammatory activity in LPS- induced Caco-2 cells.
The frequency presence of emamectin benzoate in agricultural production highlights the need for studying their toxicity against human intestinal epithelial barrier (IEB). Herein, we combined a ...Caco-2 cell model with transcriptome analysis to assess the intestinal toxicity of emamectin benzoate and its disease-causing potential. Results showed that the half maximal inhibitory concentration (IC50) of emamectin benzoate on Caco-2 cell viability after 24, 48, and 72 h of exposure were 18.1, 9.9, and 8.3 μM, respectively. Emamectin benzoate exposure enhanced the Caco-2 monolayer paracellular permeability, damaged the IEB, and increased cellular apoptosis. Key driver gene analysis of 42 apoptosis - related DEGs, identified 10 genes (XIAP, KRAS, MCL1, NRAS, PIK3CA, CYCS, MAPK8, CASP3, FADD, and TNFRSF10B) with the strongest correlation with emamectin benzoate - induced apoptosis. Transcriptomics identified 326 differentially expressed genes (DEGs, 204 upregulated and 122 downregulated). The functional terms of neurodegeneration - multiple diseases was enriched with the most number of DEGs, and the Parkinson disease pathway had the highest enrichment degree. Our findings provided support for environmental toxicology studies and the health risk assessment of emamectin benzoate.
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A series of hexafluoroisopropyl carbamates with indolylalkyl‐ and azaindolylalkyl‐substituents at the carbamate nitrogen was synthesized and evaluated for inhibition of the endocannabinoid degrading ...enzymes fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL). The synthesized derivatives with butyl to heptyl spacers between the heteroaryl and the carbamate moiety were inhibitors of both enzymes. For investigated compounds in which the alkyl chain was partially incorporated into a piperidine ring, different results were obtained. Compounds with a methylene spacer between the piperidine ring and the heteroaromatic system were found to be selective MAGL inhibitors, while an extension of the alkyl spacer to two to four atoms resulted in dual inhibition of FAAH/MAGL. The only small change in enzyme inhibitory activity with variation of the heteroaromatic system indicates that the reactive hexafluoroisopropyl carbamate group is mainly responsible for the strength of the inhibitory effect of the compounds. Selected derivatives were also tested for hydrolytic stability in aqueous solution, liver homogenate and blood plasma as well as for aqueous solubility and for permeability in a Caco‐2 cell model. Some compounds showed a slightly higher MAGL inhibitory effect than the known selective MAGL inhibitor ABX‐1431 and also partly surpassed this substance with regard to certain physicochemical and biochemical properties such as water solubility and cell permeability.
Hexafluoroisopropyl carbamates of heteroaryl‐substituted alkylamines and alkylpiperidines were investigated for their inhibitory effects on fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL). Some of these substances were found to be selective inhibitors of MAGL, while others showed dual inhibition of both enzymes. Selected compounds were evaluated for their chemical and metabolic stability, water solubility, and in vitro permeability in a Caco‐2 cell permeation model.
The Caco-2 cellular monolayer is a widely accepted in vitro model to predict human permeability but suffering from several and critical limitations. Therefore, some alternative cell cultures to mimic ...the human intestinal epithelium, as closely as possible, have been developed to achieve more physiological conditions, as the Caco-2/HT29-MTX coculture and the triple Caco-2/HT29-MTX/Raji B models. In this work the permeability of 12 model drugs of different Biopharmaceutical Classification System (BCS) characteristics, in the coculture and triple coculture models was assessed. Additionally, the utility of both models to classify compounds according to the BCS criteria was scrutinized. The obtained results suggested that the coculture of Caco-2/HT29-MTX and the triple coculture of Caco-2/HT29-MTX/Raji B were useful models to predict intestinal permeability and to classify the drugs in high or low permeability according to BCS. Moreover, to study thoroughly the transport mechanism of a specific drug, using a more complex model than Caco-2 monocultures is more suitable because coculture and triple coculture are more physiological models, so the results obtained with them will be closer to those obtained in the human intestine.
Gut microbial metabolites of polyunsaturated fatty acids have attracted much attention because of their various physiological properties. Dysfunction of tight junction (TJ) in the intestine ...contributes to the pathogenesis of many disorders such as inflammatory bowel disease. We evaluated the effects of five novel gut microbial metabolites on tumor necrosis factor (TNF)-α-induced barrier impairment in Caco-2 cells and dextran sulfate sodium-induced colitis in mice. 10-Hydroxy-cis-12-octadecenoic acid (HYA), a gut microbial metabolite of linoleic acid, suppressed TNF-α and dextran sulfate sodium-induced changes in the expression of TJ-related molecules, occludin, zonula occludens-1, and myosin light chain kinase. HYA also suppressed the expression of TNF receptor 2 (TNFR2) mRNA and protein expression in Caco-2 cells and colonic tissue. In addition, HYA suppressed the protein expression of TNFR2 in murine intestinal epithelial cells. Furthermore, HYA significantly up-regulated G protein-coupled receptor (GPR) 40 expression in Caco-2 cells. It also induced Ca2+i responses in HEK293 cells expressing human GPR40 with higher sensitivity than linoleic acid, its metabolic precursor. The barrier-recovering effects of HYA were abrogated by a GPR40 antagonist and MEK inhibitor in Caco-2 cells. Conversely, 10-hydroxyoctadacanoic acid, which is a gut microbial metabolite of oleic acid and lacks a carbon-carbon double bond at Δ12 position, did not show these TJ-restoring activities and down-regulated GPR40 expression. Therefore, HYA modulates TNFR2 expression, at least partially, via the GPR40-MEK-ERK pathway and may be useful in the treatment of TJ-related disorders such as inflammatory bowel disease.
Background: The physiological activity of gut microbial metabolites has recently attracted much attention.
Results: A gut microbial metabolite of linoleic acid, 10-hydroxy-cis-12-octadecenoic acid (HYA), ameliorates intestinal epithelial barrier impairments by regulating TNFR2 expression via the GPR40-MEK-ERK pathway.
Conclusion: HYA-induced GPR40 signaling contributes to the intestinal homeostasis.
Significance: Our findings indicate a novel function of GPR40 in the inflamed intestine.
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