Difference between revisions of "Team:NTU-LIHPAO-Taiwan/Modeling/Pathways"
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where J<sub>ss</sub> is the flux, dC<sub>R</sub>/dt is the change in conjugate concentration in the receiver chamber at steady-state, V<sub>R</sub> is the volume of receiver buffer, A is the cross sectional area of the exposed tissue, and C<sub>D</sub> is the conjugate concentration in the donor chamber. The result from Liang JF <i>et al.</i> was applied for modeling, where the value of P<sub>eff</sub> was presented as 1.62×10<sup>-5</sup> (cm/s). Moreover, the results further implied that the product seemed to be through a transcytosis-like mechanism, which confirmed that our product can penetrate through the epithelial cells.<a href="#Reference4">[4]</a> | where J<sub>ss</sub> is the flux, dC<sub>R</sub>/dt is the change in conjugate concentration in the receiver chamber at steady-state, V<sub>R</sub> is the volume of receiver buffer, A is the cross sectional area of the exposed tissue, and C<sub>D</sub> is the conjugate concentration in the donor chamber. The result from Liang JF <i>et al.</i> was applied for modeling, where the value of P<sub>eff</sub> was presented as 1.62×10<sup>-5</sup> (cm/s). Moreover, the results further implied that the product seemed to be through a transcytosis-like mechanism, which confirmed that our product can penetrate through the epithelial cells.<a href="#Reference4">[4]</a> | ||
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| + | The parameters for calculation were obtained from literatures, where <i>L. casei</i> cell size range = 0.7-1.1 x 2.0-4.0 micrometer<a href="#Reference5">[5]</a>, and the mean total mucosal surface of the small intestine interior averages 32 m<sup>2</sup> in recent research.<a href="#Reference6">[6]</a> One-tenth of the bacteria height multiplied the mucosa surface area were taken as the donor chamber volume, where one-fourth of the CPP-PYY complexes without being digested were oriented toward the epithelial cells. Finally, the flux of the complexes through villi was achieved, giving us the result of mass rate per unit volume. Figure 3 demonstrates the amount of penetrating CPP-PYY complexes though villi against time. | ||
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Revision as of 12:42, 12 September 2015
- Prototype
- Main Part
- Test Part
- Reference
Pathways
Bacteria Distribution
After orally ingested, certain amounts of modified probiotic L. casei can survive under acidic condition when passing through the stomach. Owning to gastric acid, bile acid and digestive enzymes, the presence of these bacteria in the intestinal tract only last for a limited time, and then are washed out in faeces.[1] During the process of transition and temporary colonization, CPP-PYY complexes are produced and exert the following effect.
In the first part of Modeling, bacteria distribution in the small intestine was investigated. Data from Y. K. Lee et al. showed bacteria number against time adhered on the duodenum, jejunum, and ileum in mouse after orogastric intubation of 109 L. casei, which were listed in Table 1.[2] The ratio (%) of bacteria number to total ingested number were also indicated.
By summing up all the data, we constructed the continuous L. casei cell number and ratio distribution against time with curve fitting in MATLAB, as shown in Figure 1 and Figure 2. However, experimental data from suicide mechanism should be incorporated to complete the simulation for the survival of L. casei in the small intestine, here we hypothesized 4 days for bacteria survival. Therefore, the time-changing tendency could be utilized for further calculation.
CPP-PYY Penetration Efficiency
Knowing the L. casei cell number variation against time, we proceeded to simulate the penetration process for the cell penetrating peptide, TAT with PYY. Although the mechanism for TAT translocation depends on the delivery cargo and its sequence, most papers concluded that it is mediated via an as yet uncharacterized pinocytosis/endocytosis related mechanism, which is also receptor-independent.[3]
From the experimental results of CPP-PYY complex production rate, here we took 10-10 μg/min for example, we hypothesized that one-fourth of the products secreted from the cell will be distributed in the direction toward the small intestine epithelial cells, not being digested by the intestine fluid. Liang JF et al. had provided the effective permeability (Peff) of insulin-TAT conjugates by in vitro intestinal absorption assay on cultured Caco-2 cell monolayer, which was calculated based on the following equation.[4]
where Jss is the flux, dCR/dt is the change in conjugate concentration in the receiver chamber at steady-state, VR is the volume of receiver buffer, A is the cross sectional area of the exposed tissue, and CD is the conjugate concentration in the donor chamber. The result from Liang JF et al. was applied for modeling, where the value of Peff was presented as 1.62×10-5 (cm/s). Moreover, the results further implied that the product seemed to be through a transcytosis-like mechanism, which confirmed that our product can penetrate through the epithelial cells.[4]
The parameters for calculation were obtained from literatures, where L. casei cell size range = 0.7-1.1 x 2.0-4.0 micrometer[5], and the mean total mucosal surface of the small intestine interior averages 32 m2 in recent research.[6] One-tenth of the bacteria height multiplied the mucosa surface area were taken as the donor chamber volume, where one-fourth of the CPP-PYY complexes without being digested were oriented toward the epithelial cells. Finally, the flux of the complexes through villi was achieved, giving us the result of mass rate per unit volume. Figure 3 demonstrates the amount of penetrating CPP-PYY complexes though villi against time.
Fig.2-1 Nisin Selection
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