Bioavailability and metabolism of botanical constituents and enhancement of intestinal barrier function by caffeic acid derivatives in Caco-2 cells

Public interest in botanical supplements has increased greatly in recent years as various plant materials might be used for anti-inflammatory, immunostimulatory, antioxidant and cancer preventive effects. Our long term goal is to improve our understanding of the characteristics of phytochemicals that contribute to human health benefits on gut functions, and thereby pave the way for optimizing herbal supplements for study in future clinical trials. In this dissertation, the overarching hypotheses were that major components of the ethanolic extracts of Echinacea, alkamides and ketones, and caffeic acid derivatives in the ethanolic extract of Prunella vulgaris, will be transferred by Caco-2 cell monolayers and caffeic acid derivatives will enhance the intestinal epithelial barrier function. Echinacea has long been used as phytotherapy for wound healing, pain relief and treatment of the common cold. In the first study, Bauer alkamides, the key components contained in Echinacea sanguinea and Echinaceapallida, transferred across the Caco-2 cell monolayer via passive diffusion, independent of other constituents in plant extract. The apparent permeability coefficients (Papp) were 2.8 y 1.5- 43.8 y 11.2 cm/s y10-6 for tested three alkamides and the order of the transfer of them across Caco-2 cells was increased paralleled with compound hydrophicility. Tested alkamides were seemingly N-glucuronidated and both Echinacea extracts stimulated apparent glucuronidation and basolateral efflux of alkamide metabolites. Bauer ketone 24 was totally metabolized to more hydrophilic metabolites as a pure compound, but not found in either Echinacea species. The addition of Bauer alkamides (175-230 yM) as well as the ethanolic extracts of E. sanguinea at 1 mg/mL (containing 85 yM of alkamide 8, 2 yM of alkamide 10, and 0.7 yM of alkamide 11) and E. pallida at 5 mg/mL (containing 215 yM of alkamide 8, 25 yM of alkamide 10, and 45 yM of alkamide 11) reduced the efflux of the P-glycoprotein transporter (P-gp) probe calcein-AM from Caco-2 cells. These results suggest that other constituents in the plant extract had a facilitating effect on the metabolism and efflux of alkamides and ketones from Echinacea, which would improve the therapeutic benefits of these extracts, and that alkamides and Echinacea extracts might be useful in potentiating some chemotherapeutics which are substrates for P-gp. Prunella vulgaris is a perennial herb known as self-heal used to treat sore throat, fever, and wounds. Rosmarinic acid is a caffeic acid derivative found in various botanicals, especially in P. vulgaris. Ursolic acid, a pentacyclic triterpene acid, is also found in P. vulgaris but especially concentrated in Salvia officinalis (sage), which has been traditionally used to treat inflammation in the oral cavity, and may also be of interest in inhibiting gastrointestinal inflammation which is relevant to colitis and colon cancer. In the second study, Papp for rosmarinic acid and rosmarinic acid in P. vulgaris extracts was 0.2 y 0.05 y 10-6 cm/s, significantly increased to 0.9 y 0.2 y 10-6 cm/s after β-glucuronidase/sulfatase treatment. Papp for ursolic acid and ursolic acid in S. officinalis extract was 2.7 y 0.3 y 10-6 cm/s and 2.3 y 0.5 y 10-6 cm/s before and after β-glucuronidase/sulfatase treatment, respectively. Neither compound was affected in permeability by the herbal extract matrix. These results indicate that rosmarinic acid and ursolic acid in herbal extracts had similar uptake as that found using the pure compounds, which may simplify the prediction of compound efficacy, but the apparent lack of intestinal glucuronidation/sulfation of ursolic acid is likely to further enhance the bioavailability of that compound compared with rosmarinic acid. In the third study, the effects of caffeic acid and related compounds on intestinal barrier function were investigated using Caco-2 cells as a model. Caffeic acid, rosmarinic acid, chlorogenic acid and m-hydroxyphenylpropionic acid (mHPP, a microbial metabolite of caffeic acid and rosmarinic acid) up-regulated the expression of zonula occludens (ZO -1), ZO-2, claudin-1 and occludin in Caco-2 cells. In addition, chlorogenic acid and mHPP were effective against adverse effects induced by inflammatory stimuli (LPS, interferon-γ, IL-1β, and TNF-α) on tight junction proteins in Caco-2 cells. Caffeic acid derivatives up-regulated claudin-4 in P-glycroprotein transporter MDR1- knockdown (KD) Caco-2 cells and only mHPP was effective against the changes in tight junction protein expression induced by inflammatory stimuli in MDR KD Caco-2 cells. Caffeic acid derivatives augmented TNF-α and IL-6 levels in Caco-2 cells under the stimulated condition, but significantly reduced both cytokines in MDR KD caco-2 cells plus the stimuli. These results indicate that caffeic acid derivatives enhanced barrier function in human intestinal Caco-2 cells and mHPP exhibited greater enhancement of intestinal barrier than the parent compounds. P-gp plays an essential role in the anti-inflammatory activities of caffeic acid derivatives. In conclusion, these data confirmed the overarching hypotheses and suggest that the effect of plant matrix on bioavailability and metabolism of the constituent is compound specific, depending on the transfer mechanism; and caffeic acid derivatives could be gut health promoting as a dietary constituent, but these compounds might exacerbate damage under inflammatory stimuli. Moreover, intake of caffeic acid derivatives might speed up mucosal recovery or provide protection to the small-intestinal mucosa against the inflammatory mediators when P-gp inhibitors are co-administered, which may be attractive from a therapeutic point of view

Evaluation of the green development efficiency of marine fish culture in China

Green development efficiency (GDE) is an important criterion for measuring the level of green development. GDE considers not only economic development efficiency but also environmental costs. In China, marine fish culture, as one of the pillar industries of mariculture, promotes green development and industrial transformation and upgradation. Based on data from the field surveys of marine fish farmers (2017–2019) and the China Fishery Statistical Yearbook (2018–2020), this study establishes an evaluation index system and uses the super-slack-based measure model (Super-SBM) to evaluate the GDE of marine fish culture. The results show that the average GDE of marine fish culture in China was 0.9529, which was in an inefficient state. As for culture species, golden pompano (Trachinotus ovatus) and cobia (Rachycentron canadum) were the two species farmed in an efficient state, with a GDE of 1.2107 and 1.0659, respectively. Regarding culture modes, green modes (offshore cage aquaculture, industrial recirculating aquaculture, and engineering pond aquaculture) were in an efficient state, with a GDE of 1.2310, 1.0827, and 1.0401, respectively. Traditional modes (industrial flow-through aquaculture, ordinary cage aquaculture, and ordinary pond aquaculture) were in an inefficient state, with their GDE being 0.9884, 0.8746, and 0.8248, respectively. Green modes have higher GDE than traditional modes. In contrast, the production and culture areas of green modes were less than those of traditional modes because the profits of the same species in green modes were lower than those in traditional modes. The results of this study present an objective assessment of the GDE of marine fish culture in China and provide valuable insights for analyzing the mechanisms to improve the GDE of marine fish culture

Echinacea sanguinea and Echinacea pallida Extracts Stimulate Glucuronidation and Basolateral Transfer of Bauer Alkamides 8 and 10 and Ketone 24 and Inhibit P-glycoprotein Transporter in Caco-2 Cells

The use of Echinacea as a medicinal herb is prominent in the United States, and many studies have assessed the effectiveness of Echinacea as an immunomodulator. We hypothesized that Bauer alkamides 8, 10, and 11 and ketone 24 were absorbed similarly either as pure compounds or from Echinacea sanguinea and Echinacea pallida ethanol extracts, and that these Echinacea extracts could inhibit the P-glycoprotein transporter in Caco-2 human intestinal epithelial cells. Using HPLC analysis, the permeation rate of Bauer alkamides by passive diffusion across Caco-2 cells corresponded with compound hydrophilicity (alkamide 8 \u3e 10 \u3e 11), independent of the plant extract matrix. Both Echinacea ethanol extracts stimulated apparent glucuronidation and basolateral efflux of glucuronides of alkamides 8 and 10 but not alkamide 11. Bauer ketone 24 was totally metabolized to more hydrophilic metabolites when administered as a single compound, but was also glucuronidated when present in Echinacea extracts. Bauer alkamides 8, 10, and 11 (175– 230 μM) and ethanol extracts of E. sanguinea (1 mg/mL, containing ~ 90 μM total alkamides) and E. pallida (5 mg/mL, containing 285 μM total alkamides) decreased the efflux of the P-glycoprotein transporter probe calcein-AM from Caco- 2 cells. These results suggest that other constituents in these Echinacea extracts facilitated the metabolism and efflux of alkamides and ketones, which might improve therapeutic benefits. Alkamides and Echinacea extracts might be useful in potentiating some chemotherapeutics, which are substrates for the P-glycoprotein transporter

Permeability of rosmarinic acid in Prunella vulgaris and ursolic acid in Salvia officinalis extracts across Caco-2 cell monolayers

Ethnopharmacological relevance Rosmarinic acid (RA), a caffeic acid-related compound found in high concentrations in Prunella vulgaris (self-heal), and ursolic acid (UA), a pentacyclic triterpene acid concentrated in Salvia officinalis (sage), have been traditionally used to treat inflammation in the mouth, and may also be beneficial for gastrointestinal health in general. Aim of the study To investigate the permeabilities of RA and UA as pure compounds and in Prunella vulgaris and Salvia officinalis ethanol extracts across human intestinal epithelial Caco-2 cell monolayers. Materials and methods The permeabilities and phase II biotransformation of RA and UA as pure compounds and in herbal extracts were compared using Caco-2 cells with HPLC detection. Results The apparent permeability coefficient (Papp) for RA and RA in Prunella vulgaris extracts was 0.2 ± 0.05 × 10−6 cm/s, significantly increased to 0.9 ± 0.2 × 10−6 cm/s after β-glucuronidase/sulfatase treatment. Papp for UA and UA in Salvia officinalis extract was 2.7 ± 0.3 × 10−6 cm/s and 2.3 ± 0.5 × 10−6 cm/s before and after β-glucuronidase/sulfatase treatment, respectively. Neither compound was affected in permeability by the herbal extract matrix. Conclusion RA and UA in herbal extracts had similar uptake as that found using the pure compounds, which may simplify the prediction of compound efficacy, but the apparent lack of intestinal glucuronidation/sulfation of UA is likely to further enhance the bioavailability of that compound compared with RA

Efficacy of a Mycotoxin Binder against Dietary Fumonisin, Deoxynivalenol, and Zearalenone in Rats

It was hypothesized that a mycotoxin binder, Grainsure E, would inhibit adverse effects of a mixture of fumonisin B1, deoxynivalenol, and zearalenone in rats. For 14 and 28 days, 8–10 Sprague–Dawley rats were fed control diet, Grainsure E (0.5%), toxins (7 μg fumonisin B1/g, 8 μg of deoxynivalenol/g and 0.2 μg of zearalenone/g), toxins (12 μg of fumonisin B1/g, 9 μg of deoxynivalenol/g, and 0.2 μg of zearalenone/g + Grainsure E), or pair-fed to control for food intake of toxin-fed rats. After 28 days, decreased body weight gain was prevented by Grainsure E in toxin-fed female rats, indicating partial protection against deoxynivalenol and fumonisin B1. Two effects of fumonisin B1 were partly prevented by Grainsure E in toxin-fed rats, increased plasma alanine transaminase (ALT) and urinary sphinganine/sphingosine, but sphinganine/sphingosine increase was not prevented in females at the latter time point. Grainsure E prevented some effects of fumonisin B1 and deoxynivalenol in rats

Bioavailability and metabolism of botanical constituents and enhancement of intestinal barrier function by caffeic acid derivatives in Caco-2 cells

Public interest in botanical supplements has increased greatly in recent years as various plant materials might be used for anti-inflammatory, immunostimulatory, antioxidant and cancer preventive effects. Our long term goal is to improve our understanding of the characteristics of phytochemicals that contribute to human health benefits on gut functions, and thereby pave the way for optimizing herbal supplements for study in future clinical trials. In this dissertation, the overarching hypotheses were that major components of the ethanolic extracts of Echinacea, alkamides and ketones, and caffeic acid derivatives in the ethanolic extract of Prunella vulgaris, will be transferred by Caco-2 cell monolayers and caffeic acid derivatives will enhance the intestinal epithelial barrier function. Echinacea has long been used as phytotherapy for wound healing, pain relief and treatment of the common cold. In the first study, Bauer alkamides, the key components contained in Echinacea sanguinea and Echinaceapallida, transferred across the Caco-2 cell monolayer via passive diffusion, independent of other constituents in plant extract. The apparent permeability coefficients (Papp) were 2.8 y 1.5- 43.8 y 11.2 cm/s y10-6 for tested three alkamides and the order of the transfer of them across Caco-2 cells was increased paralleled with compound hydrophicility. Tested alkamides were seemingly N-glucuronidated and both Echinacea extracts stimulated apparent glucuronidation and basolateral efflux of alkamide metabolites. Bauer ketone 24 was totally metabolized to more hydrophilic metabolites as a pure compound, but not found in either Echinacea species. The addition of Bauer alkamides (175-230 yM) as well as the ethanolic extracts of E. sanguinea at 1 mg/mL (containing 85 yM of alkamide 8, 2 yM of alkamide 10, and 0.7 yM of alkamide 11) and E. pallida at 5 mg/mL (containing 215 yM of alkamide 8, 25 yM of alkamide 10, and 45 yM of alkamide 11) reduced the efflux of the P-glycoprotein transporter (P-gp) probe calcein-AM from Caco-2 cells. These results suggest that other constituents in the plant extract had a facilitating effect on the metabolism and efflux of alkamides and ketones from Echinacea, which would improve the therapeutic benefits of these extracts, and that alkamides and Echinacea extracts might be useful in potentiating some chemotherapeutics which are substrates for P-gp. Prunella vulgaris is a perennial herb known as self-heal used to treat sore throat, fever, and wounds. Rosmarinic acid is a caffeic acid derivative found in various botanicals, especially in P. vulgaris. Ursolic acid, a pentacyclic triterpene acid, is also found in P. vulgaris but especially concentrated in Salvia officinalis (sage), which has been traditionally used to treat inflammation in the oral cavity, and may also be of interest in inhibiting gastrointestinal inflammation which is relevant to colitis and colon cancer. In the second study, Papp for rosmarinic acid and rosmarinic acid in P. vulgaris extracts was 0.2 y 0.05 y 10-6 cm/s, significantly increased to 0.9 y 0.2 y 10-6 cm/s after β-glucuronidase/sulfatase treatment. Papp for ursolic acid and ursolic acid in S. officinalis extract was 2.7 y 0.3 y 10-6 cm/s and 2.3 y 0.5 y 10-6 cm/s before and after β-glucuronidase/sulfatase treatment, respectively. Neither compound was affected in permeability by the herbal extract matrix. These results indicate that rosmarinic acid and ursolic acid in herbal extracts had similar uptake as that found using the pure compounds, which may simplify the prediction of compound efficacy, but the apparent lack of intestinal glucuronidation/sulfation of ursolic acid is likely to further enhance the bioavailability of that compound compared with rosmarinic acid. In the third study, the effects of caffeic acid and related compounds on intestinal barrier function were investigated using Caco-2 cells as a model. Caffeic acid, rosmarinic acid, chlorogenic acid and m-hydroxyphenylpropionic acid (mHPP, a microbial metabolite of caffeic acid and rosmarinic acid) up-regulated the expression of zonula occludens (ZO -1), ZO-2, claudin-1 and occludin in Caco-2 cells. In addition, chlorogenic acid and mHPP were effective against adverse effects induced by inflammatory stimuli (LPS, interferon-γ, IL-1β, and TNF-α) on tight junction proteins in Caco-2 cells. Caffeic acid derivatives up-regulated claudin-4 in P-glycroprotein transporter MDR1- knockdown (KD) Caco-2 cells and only mHPP was effective against the changes in tight junction protein expression induced by inflammatory stimuli in MDR KD Caco-2 cells. Caffeic acid derivatives augmented TNF-α and IL-6 levels in Caco-2 cells under the stimulated condition, but significantly reduced both cytokines in MDR KD caco-2 cells plus the stimuli. These results indicate that caffeic acid derivatives enhanced barrier function in human intestinal Caco-2 cells and mHPP exhibited greater enhancement of intestinal barrier than the parent compounds. P-gp plays an essential role in the anti-inflammatory activities of caffeic acid derivatives. In conclusion, these data confirmed the overarching hypotheses and suggest that the effect of plant matrix on bioavailability and metabolism of the constituent is compound specific, depending on the transfer mechanism; and caffeic acid derivatives could be gut health promoting as a dietary constituent, but these compounds might exacerbate damage under inflammatory stimuli. Moreover, intake of caffeic acid derivatives might speed up mucosal recovery or provide protection to the small-intestinal mucosa against the inflammatory mediators when P-gp inhibitors are co-administered, which may be attractive from a therapeutic point of view.</p

Study on the Ablation of the Glacier Covered by Mineral Dust in Alpine Regions

Glaciers, known as solid reservoirs, are important water supply sources in northwest China. In this paper, mineral dust collected from a Chinese alpine mining area (Beizhan iron mine) and an ice cube (with a 225 cm2 section and a volume of 1000 mL) were employed via a delicate physical experiment to study the ablation of glaciers covered by mineral dust in alpine regions. After that, the ablation mechanism was revealed using the energy conservation theory. The main findings are as follows: (1) When the solar radiation intensity is 993 W/m2, the glacier ablation rate increases by 13.9% (from 282 to 321.2 mL/h) as the mineral dust coverage rate increases from 0% to 42.7%. (2) When the mineral dust coverage rate remains at 30%, the glacier ablation rate increases by 11.6% (from 291.8 to 325.78 mL/h) as the solar radiation intensity increases from 1007 to 1153 W/m2. (3) When the solar radiation intensity and mineral dust coverage rate remain unchanged, the ablation rate of the glacier covered by the mineral dust inversely increases with the dust particle size. The ablation rates of the particle size gradings C, B, and A (the dust particle sizes of gradings A, B, and C in 0.0375&ndash;0.075 mm, 0.075&ndash;0.125 mm, and 0.125&ndash;0.25 mm accounted for 5%:50%:45%, 30%:40%:30%, and 70%:30%:0%, respectively) were 293.4, 301.2, and 305.6 mL /h, respectively, and the corresponding ablation rates increased by 2.7% and 1.5%. (4) The smaller the average particle size of the mineral dust, the greater the contribution to the ablation rate; a 1 &deg;C temperature increase to the glacier ablation rate is equivalent to 29.1%, 33.6%, and 40.6% increases in dust coverage for particle size classes C, B, and A. (5) The mineral dust covering the glacier surface could not only reduce the reflectivity of the glacier surface to solar radiation but could also continuously transfer the absorbed radiant energy and its own chemical energy to the glacier body, accelerating the glacier&rsquo;s meltwater speed. The findings of this paper can provide the necessary theoretical basis for mineral dust control and glacier water conservation in alpine mining areas

Xenon lamp control signal and drive circuit design of Er: YAG laser

When the Er: YAG laser pumped by a xenon lamp emits laser light, the energy, frequency and pulse width of the emitted light are closely related to the discharge of the xenon lamp. This article uses the 8MHz external crystal oscillator that comes with the STM32F4 development board, generates a clock source through frequency division and frequency multiplication, and configures a pulse width modulation (PWM) signal to control the laser. Since the signals sent by the development board are weak signals, it is necessary to design a corresponding drive circuit to amplify the power of the signal. Finally, the voltage of the pulsed xenon lamp is adjustable from 0 to 1400V, and the pulse width is adjustable from 50 to 300μs to achieve stable laser output

Multi-Speaker Video Dialog with Frame-Level Temporal Localization

To simulate human interaction in real life, dialog systems are introduced to generate a response to previous chat utterances. There have been several studies for two-speaker video dialogs in the form of question answering. However, more informative semantic cues might be exploited via a multi-rounds chatting or discussing about the video among multiple speakers. So multi-speakers video dialogs are more applicable in real life. Besides, speakers always chat about a sub-segment of the long video fragment for a period of time. Current video dialog systems require to be directly given the relevant video sub-segment which speakers are chatting about. However, it is always hard to accurately spot the corresponding video sub-segment in practical applications. In this paper, we introduce a novel task of Multi-Speaker Video Dialog with frame-level Temporal Localization (MSVD-TL) to make video dialog systems more applicable. Given a long video fragment and a set of chat history utterances, MSVD-TL targets to predict the following response and localize the relevant video sub-segment in frame level, simultaneously. We develop a new multi-task model with a response prediction module and a frame-level temporal localization module. Besides, we focus on the characteristic of the video dialog generation process and exploit the relation among the video fragment, the chat history, and the following response to refine their representations. We evaluate our approach for both the Multi-Speaker Video Dialog without frame-level temporal localization (MSVD w/o TL) task and the MSVD-TL task. The experimental results further demonstrate that MSVD-TL enhances the applicability of video dialog in real life