Evaluation of antioxidant activities of ethanol extract from Ligusticum subjected to in-vitro gastrointestinal digestion

Gastrointestinal digestion assays for evaluating the bioaccessibility of phenolic compounds in fruits and their derivates: an overview

Fruits and their derivatives are sources of phenolic compounds, which contribute to the maintenance of health benefits. In order to exert such properties, these compounds must be exposed to gastrointestinal conditions during digestion. In vitro methods of gastrointestinal digestion have been developed to simulate and evaluate the changes that compounds undergo after being exposed to various conditions. We present, in this review, the major in vitro methods for evaluating the effects of gastrointestinal digestion of phenolic compounds in fruits and their derivatives. We discuss the concept of bioaccessibility, bioactivity, and bioavailability, as well as the conceptual differences and calculations among studies. Finally, the main changes caused by in vitro gastrointestinal digestion in phenolic compounds are also discussed. The significant variation of parameters and concepts observed hinders a better evaluation of the real effects on the antioxidant activity of phenolic compounds, thus, the use of standardized methods in research would contribute for a better understanding of these changes.

Insight of "Yin-Jing" medical property ofLigusticum chuanxiong Hort. via pharmacokinetics and tissue distributions by ultra-performance liquid chromatography-triple quadrupole mass spectrometry

ETHNOPHARMACOLOGICAL RELEVANCE

Ligusticum chuanxiong Hort. (Chuanxiong, LC), as an important traditional Chinese medicine (TCM), can not only be used as a monarch herb but also be used as a classic "Yin-Jing" () medicine in compound prescriptions, e.g., Buyang Huanwu Decoction (BHD). Although LC has the effect of guiding components into the brain in BHD, there is still a lack of scientific evidence on this "Yin-Jing" effects. Herein, we used pharmacokinetics and tissue distributions to investigate "Yin-Jing" effects of LC. To simplify the study, four major constituents in BHD, i.e., Calycosin (CA), astragaloside IV (AI), paeoniflorin (PA), and amygdalin (AM) were combined to form a simple compound (abbreviated as CAPA here) to replace the original BHD in this paper. The Yin-Jing medical property of LC was confirmed by the compatibility of CAPA with LC or its different fractions (Fr. A ∼ Fr. F).

AIM OF THE STUDY

To explore the "Yin-Jing" medical property of LC via pharmacokinetics and tissue distributions by ultra-performance liquid chromatography-triple quadrupole mass spectrometry (UPLC-QQQ-MS).

MATERIALS AND METHODS

The contents of CA, AI, PA, and AM were simultaneously determined by the established and validated UPLC-QQQ-MS method in different rat tissues and plasma after administration of CAPA with the combination of LC or Fr. A ∼ Fr. F. The pharmacokinetic parameters, e.g., T_max, C_max, AUC_0-t and MRT_0-t, were calculated to evaluate the efficiency of "Yin-Jing".

RESULTS

The C_max and AUC_0-t of CA, AI, PA, and AM were remarkably increased in rat brain tissues compared with those of the control group after compatibility of LC. This demonstrated that LC has the Yin-Jing effects on brain tissues. Additionally, Fr. B or Fr. C might be the material basis by specifically studying the distributions of CA, AI, PA, and AM in brain tissue based on mutual compatibility. The effects of Fr. B and Fr. C on distributions of these constituents in other tissues or plasma was also studied to verify the effects of Yin-Jing of LC. The results showed that the same upward trend is found in heart, liver and plasma, but the intensity is insignificant as that in brain tissue. Furthermore, the C_max and AUC_0-t of some analytes in the rat spleen, lung, and kidney were significantly decreased compared with the control group (P < 0.05 or 0.01).

CONCLUSIONS

LC has the function of Yin-Jing, especially guiding the components into the brain tissue. Moreover, Fr. B and Fr. C is suggested to be the pharmacodynamic material basis for the effect of Yin-Jing of LC. These finding explained that it was recommended to add LC into some prescriptions for treating cardiovascular and cerebrovascular diseases caused by Qi deficiency and blood stasis. This has laid a certain foundation for the research on the Yin-Jing efficacy of LC to better clarify the theory of TCM and guide the clinical application of Yin-Jing drugs.

Multi-Index Comprehensive Assessment Optimized Critical Flavonoids Extraction from Semen Hoveniae and Their In Vitro Digestive Behavior Evaluation

Critical flavonoids from Semen Hoveniae have huge potential bioactivities on hypoglycemic. A multi-index comprehensive assessment based on Analytic Hierarchy Process (AHP) method was performed to optimize the extraction process of flavonoids from Semen Hoveniae, which taking dihydromyricetin, taxifolin, myricetin and quercetin as indexes, and, then, an in vitro simulated gastrointestinal digestion model was established to investigate the changes of flavonoids contents and their antioxidant capacity before and after digestion. The results showed that three influence factors acted significantly with the order of ethanol concentration > solid-liquid ratio > ultrasound time. The optimized extraction parameters were as follows: 1:37 w/v of solid-liquid ratio, 68% of ethanol concentration and 45 min for ultrasonic time. During in vitro digestion, the order of remaining ratio of four flavonoids in the extract was dihydromyricetin > taxifolin > myricetin > quercetin in gastric digestion, and remaining ratio of taxifolin was 34.87% while others were restructured in intestinal digestion. Furthermore, the 1,1-dipheny-2-picryhydrazyl free radical (DPPH ·) scavenging ability and oxygen radical absorption capacity (ORAC) of extract were more stable in gastric digestion. After an hour's intestinal digestion, the extract had no DPPH antioxidant capacity, but amazingly, its ORAC antioxidant capacity was retained or increased, which implied that substances were transformed and more hydrogen donors were produced. This study has carried out a preliminary discussion from the perspective of extraction and put forward a new research idea, to improve the in vivo bioavailability of the critical flavonoids from Semen Hoveniae.

Studies on the mechanism of energy metabolism via AMPK/PGC-1α signaling pathway induced by compatibility of Ligusticum chuanxiong Hort and Gastrodia

AMP-activated protein kinase (AMPK) regulates overall energy consumption and energy intake through cytokines. Ligusticum striatum DC (CX) combined with Gastrodia elata Blume (TM) has been used for migraine treatment for millennia. When used alone in clinical practice, CX causes symptoms of thirst, irritability, and yellow urine and has influenced the levels of cytokines such as AMP that activate the AMPK pathway of energy metabolism. However, relationships between this compatibility prescription, integral biological energy metabolism, and the AMPK pathway remain unclear. Studies were performed by treating normal rats with physiological saline, CX extract, CX coupled TM extract, and TM extracts separately for 4 weeks. Food intake, water intake, urine output, stool output, and body weight were monitored once a week by the metabolic cage method. Values of FBG, BUN, TP, TC and TG in blood samples were detected approaching the whole blood automatic detector from 1 to 4 weeks. Na+ -K+ -ATPase, Ca2+ -Mg2+ -ATPase, cAMP, and cGMP activity were determined by the enzyme-linked immunosorbent assay (ELISA); the biological samples that were obtained at 1, 2, 3, and 4 weeks after drug administration were tested by GC-TOF-MS. Then real-time PCR and Western Blot were applied to detect changes in expression of some substances involved in energy metabolism. The results demonstrated that administering CX alone increased energy input, mobility, and respiratory exchange ratio, accelerated energy consumption, and caused inflammatory infiltration in the liver. CX coupled with TM led to lower energy metabolism and liver damage in comparison with CX used alone. Moreover, CX-treated rats harbored higher levels of differential metabolites (including pyrophosphate, oxaloacetic acid, and galactinol). Glycerophospholipid metabolism and the citrate cycle are closely related to the differential metabolites above. In addition, CX-induced unbalanced energy metabolism depends on cAMP activation mediated by the AMPK/PGC-1α pathway in rats. Our findings suggest that CX-induced energy metabolism imbalance was corrected after coupling with TM by mediating the AMPK/PGC-1α pathway.

An Ethnopharmaceutical Study on the Hypolipidemic Formulae in Taiwan Issued by Traditional Chinese Medicine Pharmacies

Globally, approximately one-third of ischemic heart diseases are due to hyperlipidemia, which has been shown to cause various metabolic disorders. This study was aimed to disassemble and analyze hypolipidemic formulae sold by traditional Chinese medicine (TCM) pharmacies. Using commonly used statistical parameters in ethnopharmacology, we identified the core drug combination of the hypolipidemic formulae, thereby exploring the strategy by which the Taiwanese people select hypolipidemic drugs. Most important of all, we preserved the inherited knowledge of TCM. We visited 116 TCM pharmacies in Taiwan and collected 91 TCM formulae. The formulae were mainly disassembled by macroscopical identification, and the medicinal materials with a relative frequency of citation (RFC) >0.2 were defined as commonly used medicinal materials. Subsequently, we sorted the information of medicinal materials recorded in the Pharmacopeia, searched for modern pharmacological research on commonly used medicinal materials using PubMed database, and visualized data based on the statistical results. Finally, the core hypolipidemic medicinal materials used in folk medicine were obtained. Of the 91 TCM formulae collected in this study, 80 traditional Chinese medicinal materials were used, belonging to 43 families, predominantly Lamiaceae. Roots were the most commonly used part as a medicinal material. There were 17 commonly used medicinal materials. Based on medicinal records in Pharmacopeia, most flavors and properties were warm and pungent, the majority traditional effects were “tonifying and replenishing” and “blood-regulating.” Besides, the targeted diseases searching from modern pharmacological studies were diabetes mellitus and dyslipidemia. The core medicinal materials consisted of Astragalus mongholicus Bunge and Crataegus pinnatifida Bunge, and the core formulae were Bu-Yang-Huan-Wu-Tang and Xie-Fu-Zhu-Yu-Tang. In addition, 7 groups of folk misused medicinal materials were found. Although these TCMs have been used for a long period of time, their hypolipidemic mechanisms remain unclear, and further studies are needed to validate their safety and efficacy.

Influence of Simulated In Vitro Gastrointestinal Digestion on the Phenolic Profile, Antioxidant, and Biological Activity of Thymbra spicata L. Extracts

Plants or plant extracts are widely investigated for preventing/counteracting several chronic disorders. The oral route is the most common route for nutraceutical and drug administration. Currently, it is still unclear as to whether and how the pattern of phenolic compounds (PCs) found in the plants as well as their bioactivity could be modified during the gastrointestinal transit. Recent studies have revealed antioxidant and anti-steatotic properties of Thymbra spicata. Here, we investigated the possible loss of phytochemicals that occurs throughout the sequential steps of a simulated in vitro gastrointestinal (GI) digestion of aqueous and ethanolic extracts of aerial parts of T. spicata. Crude, digested, and dialyzed extracts were characterized in terms of their phenolic profile and biological activities. Total contents of carbohydrates, proteins, PCs, flavonoids, and hydroxycinnamic acids were quantified. The changes in the PC profile and in bioactive compounds upon the simulated GI digestion were monitored by HPLC–MS/MS analysis. The antioxidant activity was measured by different spectrophotometric assays, and the antiproliferative potential was assessed by using three representative human cancer cell lines. We observed that the simulated GI digestion reduced the phytochemical contents in both aqueous and ethanolic T. spicata extracts and modified the PC profile. However, T. spicata extracts improved their antioxidant potential after digestion, while a partial reduction in the antiproliferative activity was observed for the ethanolic extract. Therefore, our results could provide a scientific basis for the employment of T. spicata extract as valuable nutraceutical.

Dosage Modification of Traditional Chinese Medicine Prescriptions: An Analysis of Two Randomized Controlled Trials

Traditional Chinese medicine (TCM) prescriptions lack standardization due to the complex composition of the prescribed herbs, the unclear mechanism of the formulas, and a lack of scientific data to support the dose-response relationship. Here, we proposed a new clinical strategy of dosage modification for TCM prescriptions to evaluate the clinical efficacy and guide the clinical medication. This study used two TCM prescriptions for the treatment of newly diagnosed type 2 diabetes mellitus (T2DM) to explore the key indications and the most appropriate critical values of dosage modification by analyzing two randomized controlled trials (RCTs). In this study, the indications refer to a change in the indicators from baseline at a certain time point (week 4, week 8, week 12), which could predict the change in outcome indicators, and the critical values refer to the change ranges closely related to the decrease in HbA1c at week 12. In Study 1, the correlation analysis between the change range of indicators at three time points (weeks 4, 8, and 12) from baseline and the decrease in HbA1c at week 12 from baseline (HbA1c 012) was carried out to screen the related indications. Next, we evaluate the related indications and the respective critical values to determine the key indicators, indications, and the most appropriate critical value. We conducted a correlation between the change range of key indicators (obtained from the result of Study 1) at three time points from baseline and HbA1c 012 to screen the key indications in the drug group, high-dose group, and low-dose group in Study 2. Key indications with critical values were determined to investigate the most appropriate critical value in the three groups separately. In Study 1, the key indicator was FBG, the key indication was FBG 04, and the most appropriate critical value was 0.5 mmol/L. In Study 2, the key indication was FBG 04 and the most appropriate critical value was 0.6 mmol/L in the drug group. In the high-dose group, the key indication was FBG 04, and the most appropriate critical value was 0.3 mmol/L. In the low-dose group, the key indication was FBG08, and the most appropriate critical value was 0.1 mmol/L. In addition, we summarized a verification strategy for dosage modification.

Diversity, Chemical Constituents, and Biological Activities of Endophytic Fungi Isolated From Ligusticum chuanxiong Hort

The objective of this study was to evaluate the diversity of endophytic fungi of different parts of Ligusticum chuanxiong Hort (CX) and further characterize their biological activities and identify chemical compounds produced by these endophytic fungi. A total of 21 endophytic fungi were isolated and identified from CX. Penicillium oxalicum, Simplicillium sp., and Colletotrichum sp. were identified as promising strains by the color reaction. Comparing different organic extracts of the three strains, it was observed that the ethyl acetate extract of Penicillium oxalicum and Simplicillium sp. and the n-butanol extract of Colletotrichum sp. showed significant antioxidant and antibacterial activities. The ethyl acetate extracts of Penicillium oxalicum had outstanding antioxidant and antibacterial effects, and its radical scavenging rates for ABTS and DPPH were 98.43 ± 0.006% and 90.11 ± 0.032%, respectively. At the same time, their IC₅₀ values were only 0.18 ± 0.02 mg/mL and 0.04 ± 0.003 mg/mL. The ethyl acetate extract of Penicillium oxalicum showed MIC value of only 0.5 mg/mL against Escherichia coli and Staphylococcus aureus. By liquid chromatography-mass spectrometry (LC-MS), we found that Penicillium oxalicum could produce many high-value polyphenols, such as hesperidin (36.06 μmol/g), ferulic acid (1.17 μmol/g), and alternariol (12.64 μmol/g), which can be a potential resource for the pharmaceutical industry. In conclusion, these results increase the diversity of CX endophytic fungi and the antioxidant and antibacterial activities of their secondary metabolites.

Simulated gastrointestinal digestion of Brazilian açaí seeds affects the content of flavan-3-ol derivatives, and their antioxidant and anti-inflammatory activities

Açaí seeds (Euterpe oleracea Mart.) are the major residue generated during industrial extraction of açaí fruit pulp - a popular and typical Amazon fruit rich in bioactive compounds and nutrients. In this study, we investigated the bioaccessibility of an açaí seed extract using an in vitro simulated gastrointestinal digestion model. Catechin, epicatechin and procyanidins B1 and B2 were identified and quantified in the açaí seed extract and monitored by HPLC-DAD through the digestion phases. Bioaccessibility of these flavan-3-ols and deactivation of reactive oxygen species decreased after the intestinal phase, except for peroxyl radical (ROO^●). RAW 264.7 macrophages treated either with the digested or undigested açaí seed extract showed reduced NF-κB activation and TNF-α levels, even following gastrointestinal digestion. Thus, the ROO^● scavenging capacity and anti-inflammatory activity of the extract were found to be still remarkable after digestion, suggesting that açaí seeds could be explored as a source of bioactive compounds for functional foods, cosmetic or pharmaceutical purposes.

Chuanxiong (Rhizome of Ligusticum chuanxiong) Protects Ovariectomized Hyperlipidemic Rats from Bone Loss

Oxidative stress (OS) is the common mechanism for age-related diseases. The co-occurrence of osteoporosis (OP) and cardiovascular disease (CVD) in postmenopausal women makes it warranted to find a holistic approach for treatment of multiple diseases or conditions. The rhizome of Ligusticum chuanxiong Hort. (CX), which has high anti-oxidant properties and is widely used for CVD treatment in China, might be the potential candidate. In the present study, CX ethanol extract (CXE) was applied to H₂O₂ induced MG63 cells to study its effects and mechanisms on osteoblastogenesis against OS. CXE was then administered to six-month-old Sprague Dawley sham or ovariectomized (OVX) rats fed either a low saturated fat-sucrose (LFS) or a high fat-sucrose (HFS) diet for 12 weeks, to confirm its anti-osteoporotic effects. The results demonstrated that CXE directly improved proliferation and differentiation in vitro in an H₂O₂-induced osteoblast cell model by attenuating cellular reactive oxygen species levels and inhibiting osteoblast apoptosis via PI3K/Akt signaling pathway. CXE significantly improved bone properties as revealed by the increase in trabecular bone mineral density and decrease in trabecular separation at proximal metaphysis of the tibia (PT) in HFS-fed OVX rats but not in LFS-fed OVX rats. CXE ameliorated dyslipidemia, greatly reduced lipid deposition and malondialdehyde levels, improved activities of superoxide dismutase, catalase and glutathione peroxidase in the livers of HFS-fed OVX rats. In conclusion, CXE could favor osteoblastogenesis against OS. The ability of CXE to reduce bone loss in HFS-fed OVX rats was associated with its abilities to correct dyslipidemia, and reduce lipid deposition and OS levels.

Impact of Drug Metabolism/Pharmacokinetics and their Relevance Upon Traditional Medicine-based Cardiovascular Drug Research

BACKGROUND

The representative cardiovascular herbs, i.e. Panax, Ligusticum, Carthamus, and Pueraria plants, are traditionally and globally used in the prevention and treatment of various cardiovascular diseases. Modern phytochemical studies have found many medicinal compounds from these plants, and their unique pharmacological activities are being revealed. However, there are few reviews that systematically summarize the current trends of Drug Metabolism/Pharmacokinetic (DMPK) investigations of cardiovascular herbs.

METHODS

Here, the latest understanding, as well as the knowledge gaps of the DMPK issues in drug development and clinical usage of cardiovascular herbal compounds, was highlighted.

RESULTS

The complicated herb-herb interactions of cardiovascular Traditional Chinese Medicine (TCM) herb pair/formula significantly impact the PK/pharmacodynamic performance of compounds thereof, which may inspire researchers to develop a novel herbal formula for the optimized outcome of different cardiovascular diseases. While the Absorption, Distribution, Metabolism, Excretion and Toxicity (ADME/T) of some compounds has been deciphered, DMPK studies should be extended to more cardiovascular compounds of different medicinal parts, species (including animals), and formulations, and could be streamlined by versatile omics platforms and computational analyses.

CONCLUSION

In the context of systems pharmacology, the DMPK knowledge base is expected to translate bench findings to clinical applications, as well as foster cardiovascular drug discovery and development.

Effects of thermal preparation and in vitro digestion on lignan profiles and antioxidant activity in defatted-sesame meal

Defatted-sesame meal (DSM), a byproduct of sesame oil, has attracted considerable interest in the food industry because of its strong antioxidant activity. The aim of this study was to measure the content and distribution of lignans in DSM and evaluate their antioxidant activity after thermal processing and in vitro digestion. The results showed that the sesame lignans (SL) content and antioxidant activity were significantly influenced by the temperature and time during thermal preparation, and the maximum antioxidant potency composite index (ACI) was obtained after roasting the samples at 240 °C for 20 min. As sesame seed was processed with longer time and higher temperature, more pinoresinol diglucoside (PD) and sesamol were measured in DSM. According to the correlation matrix under thermal preparation, a significant contribution to the antioxidant potency of DSM was discovered. After in vitro digestion, the release amount of lignans increased by 19.6%, and the values of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and ACI gradually declined after digestion, with a 40% decrease in both the DPPH radical scavenging activity and the ACI from oral to intestinal phase. These results could be used to help improve the bioavailability of SL and obtaining high quality sesame byproducts.