A comparative study of the antioxidant and intestinal protective effects of extracts from different parts of Java tea (Orthosiphon stamineus)

Physical properties, phenolic profile and antioxidant capacity of Java tea (Clerodendranthus spicatus) stems as affected by steam explosion treatment

Java tea (Clerodendranthus spicatus) has been favored for its various health benefits and abundance of phenolic substances. Steam explosion (SE) treatment was performed in the pretreatment of Java tea stems and the physical properties, phenolic profile and antioxidant capacity were investigated. Extraction kinetics study showed that the phenolics yields of Java tea stems treated at 2.4 MPa for 10 min reached the maximum in 40 min, which was approximately 3 times the yields of raw stems in 180 min. The antioxidant activities of the extracts of Java tea stems were also significantly increased after SE treatment (P < 0.05). In addition, 19 phenolics were detected in Java tea stems by HPLC/QTOF-MS/MS, and rosmarinic acid was found to be hydrolyzed to danshensu during the SE process. SE could be an efficient pretreatment technology to improve the extraction rates of phenolics and conversions of their high-value hydrolyzed products, which could facilitate further research of Java tea products.

Clerodendranthus spicatus inhibits epithelial-mesenchymal transition of renal tubular cells through the NF-κB/Snail signalling pathway in hyperuricaemia nephropathy

CONTEXT

Clerodendranthus spicatus Thunb. (Labiatae) (CS), a perennial traditional Chinese medicinal herb that can reduce serum uric acid (sUA) levels and ameliorate renal function is widely used to treat hyperuricaemic nephropathy (HN).

OBJECTIVE

To investigate the molecular mechanism of action of CS in HN treatment using in vivo and in vitro experiments.

MATERIALS AND METHODS

Sprague-Dawley rats were randomly divided into control, HN, CS and positive control allopurinol groups. The HN group was intraperitoneally injected with 750 mg/kg oxonic acid potassium (OA), whereas the CS group was injected with OA along with a gavage of CS (low dose 3.125 g/kg, high dose 6.25 g/kg) for five weeks. For in vitro studies, uric acid-treated HK2 cells were used to verify the therapeutic mechanism of CS in HN.

RESULTS

HN rats exhibit pathological phenotypes of elevated sUA levels and renal injury. CS significantly improved these symptoms and sUA (p < 0.05) and blood urea nitrogen (p < 0.01) levels, and dramatically improved renal tubular injury in HN rats. The IC50 value of UA (uric acid) in HK2 cells was 826.32 ± 3.55 μg/mL; however, 120 ng/mL CS had no significant cytotoxicity on HK2 cells. In vivo and in vitro studies showed that CS inhibited NF-κB phosphorylation and inhibited α-smooth muscle actin (α-SMA) and vimentin expression while increasing E-cadherin expression, suggesting that CS inhibited the fibrotic process in renal cells, thus protecting renal function.

DISCUSSION AND CONCLUSIONS

These findings provide a fundamental understanding of the application of CS in HN treatment to better guide clinical interventions.

Metabolomics Analysis and Antioxidant Potential of Endophytic Diaporthe fraxini ED2 Grown in Different Culture Media

Endophytic fungi are a promising source of bioactive metabolites with a wide range of pharmacological activities. In the present study, MS-based metabolomics was conducted to study the metabolomes variations of endophytic Diaporthe fraxini ED2 grown in different culture media. Total phenolic content (TPC), total flavonoid content (TFC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), and ferric reducing antioxidant power (FRAP) assays were conducted to assess the antioxidant potential of the fungal extracts. Multivariate data analysis (MVDA) was employed in data analysis and interpretation to elucidate the complex metabolite profile. The supplemented culture medium of D. fraxini fungal extract stimulated the production of metabolites not occurring in the normal culture medium. Antioxidant activity studies revealed the potential of supplemented cultured fungal extract of D. fraxini as a source of antioxidants. The present findings highlight that fungal culture medium supplementation is an effective approach to unravelling the hidden metabolome in plant-associated fungal diversity.

Porcine and Chicken Intestinal Epithelial Cell Models for Screening Phytogenic Feed Additives—Chances and Limitations in Use as Alternatives to Feeding Trials

Numerous bioactive plant additives have shown various positive effects in pigs and chickens. The demand for feed additives of natural origin has increased rapidly in recent years to support the health of farm animals and thus minimize the need for antibiotics and other drugs. Although only in vivo experiments can fully represent their effect on the organism, the establishment of reliable in vitro methods is becoming increasingly important in the goal of reducing the use of animals in experiments. The use of cell models requires strict control of the experimental conditions so that reliability and reproducibility can be achieved. In particular, the intestinal porcine epithelial cell line IPEC-J2 represents a promising model for the development of new additives. It offers the possibility to investigate antioxidative, antimicrobial, anti- or pro-proliferative and antiviral effects. However, the use of IPEC-J2 is limited due to its purely epithelial origin and some differences in its morphology and functionality compared to the in vivo situation. With regard to chickens, the development of a reliable intestinal epithelial cell model has attracted the attention of researchers in recent years. Although a promising model was presented lately, further studies are needed to enable the standardized use of a chicken cell line for testing phytogenic feed additives. Finally, co-cultivation of the currently available cell lines with other cell lines and the development of organoids will open up further application possibilities. Special emphasis was given to the IPEC-J2 cell model. Therefore, all publications that investigated plant derived compounds in this cell line were considered. The section on chicken cell lines is based on publications describing the development of chicken intestinal epithelial cell models.

Tea Polyphenols: A Natural Antioxidant Regulates Gut Flora to Protect the Intestinal Mucosa and Prevent Chronic Diseases

The intestinal tract of a healthy human body hosts many microorganisms that are closely linked to all aspects of people’s lives. The impact of intestinal flora on host health is no longer limited to the gut but can also affect every organ in the body through various pathways. Studies have found that intestinal flora can be altered by external factors, which provides new ideas for treating some diseases. Tea polyphenols (TP), a general term for polyphenols in tea, are widely used as a natural antioxidant in various bioactive foods. In recent years, with the progress of research, there have been many experiments that provide strong evidence for the ability of TP to regulate intestinal flora. However, there are very few studies on the use of TP to modify the composition of intestinal microorganisms to maintain health or treat related diseases, and this area has not received sufficient attention. In this review, we outline the mechanisms by which TP regulates intestinal flora and the essential role in maintaining suitable health. In addition, we highlighted the protective effects of TP on intestinal mucosa by regulating intestinal flora and the preventive and therapeutic effects on certain chronic diseases, which will help further explore measures to prevent related chronic diseases.

A Systematic Review of Orthosiphon stamineus Benth. in the Treatment of Diabetes and Its Complications

(1) Background: Orthosiphon stamineus Benth. is a traditional medicine used in the treatment of diabetes and chronic renal failure in southern China, Malaysia, and Thailand. Diabetes is a chronic metabolic disease and the number of diabetic patients in the world is increasing. This review aimed to systematically review the effects of O. stamineus in the treatment of diabetes and its complications and the pharmacodynamic material basis. (2) Methods: This systematic review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), using the databases ScienceDirect, PubMed, and Web of Science. (3) Results: Thirty-one articles related to O. stamineus and diabetes were included. The mechanisms of O. stamineus in the treatment of diabetes and its complications mainly included inhibiting α-amylase and α-glucosidase activities, antioxidant and anti-inflammatory activities, regulating lipid metabolism, promoting insulin secretion, ameliorating insulin resistance, increasing glucose uptake, promoting glycolysis, inhibiting gluconeogenesis, promoting glucagon-likepeptide-1 (GLP-1) secretion and antiglycation activity. Phenolic acids, flavonoids and triterpenoids might be the main components for hypoglycemia effects in O. stamineus. (4) Conclusion: O. stamineus could be an antidiabetic agent to treat diabetes and its complications. However, it needs further study on a pharmacodynamic substance basis and the mechanisms of effective constituents.

A New Strategy to Investigate the Efficacy Markers Underlying the Medicinal Potentials of Orthosiphon stamineus Benth

Orthosiphon stamineus Benth. (OSB) is a well-known herbal medicine exerting various pharmacological effects and medicinal potentials. Owing to its complex of phytochemical constituents, as well as the ambiguous relationship between phytochemical constituents and varied bioactivities, it is a great challenge to explore which constituents make a core contribution to the efficacy of OSB, making it difficult to determine the efficacy makers underlying the varied efficacies of OSB. In our work, a new strategy was exploited and applied for investigating efficacy markers of OSB consisting of phytochemical analysis, in vivo absorption analysis, bioactive compound screening, and bioactive compound quantification. Using liquid chromatography coupled with mass spectrometry, a total of 34 phytochemical components were detected in the OSB extract. Subsequently, based on in vivo absorption analysis, 14 phytochemical constituents in the form of prototypes were retained as potential bioactive compounds. Ten diseases were selected as the potential indications of OSB based on previous reports, and then the overall interaction between compounds, action targets, action pathways, and diseases was revealed based on bioinformatic analysis. After refining key pathways and targets, the interaction reversing from pathways, targets to constituents was deduced, and the core constituents, including tanshinone IIA, sinensetin, salvianolic acid B, rosmarinic acid, and salvigenin, were screened out as the efficacy markers of OSB. Finally, the contents of these five constituents were quantified in three different batches of OSB extracts. Among them, the content of salvianolic acid B was the highest while the content of tanshinone IIA was the lowest. Our work could provide a promising direction for future research on the quality control and pharmacological mechanism of OSB.

The Protective Effects of Orthosiphon stamineus Extract Against Intestinal Barrier Injury in High-Fat Diet-Induced Mouse and Oxidative Stress Cell Models

Orthosiphon stamineus Benth. (Lamiaceae) is commonly used for the treatment of kidney diseases, but its role in intestinal barrier function remains unknown. The present study investigated the protective effects of O. stamineus extract (OE) against oxidative stress-induced injury to the small intestinal epithelium and the possible mechanism. High-performance liquid chromatography fingerprinting was used to analyze OE. Oxidative stress was induced by hydrogen peroxide (1 mM for 1 hour) in an IPEC-J2 cell monolayer model and a high-fat diet in C57BL/6 mice (8 weeks). The malondialdehyde (MDA) content was tested in both models. To evaluate permeability, transepithelial electrical resistance (TEER) was tested in a cell model. Serum diamine oxidase (DAO) and endotoxin contents were determined in a mouse model, and histological sections were analyzed. The messenger ribonucleic acid expression of tight junction proteins was measured by quantitative real-time polymerase chain reaction. Pretreatment with OE (50 µg/mL) increased the IPEC-J2 cell monolayer TEER (12.4%) and decreased MDA (from 6.1 to 4.7 mmol/mg prot). Oral administration of OE (100 mg/kg) decreased serum DAO (34.2%), endotoxin (13.4%), and MDA (from 21.3 to 11.0 mmol/mL) in mice. OE upregulated ZO-1 (42.8% in the cell model and 125.0% in mice) and occluding (127.0% in the cell model and 120.3% in mice) gene expression. These results confirmed the protective effect of OE on the intestinal barrier, which was associated with the antioxidant effect of OE; thus, OE is suitable for the prevention and treatment of intestinal barrier injury.

Micropropagation and Secondary Metabolites Content of White-Purple Varieties of Orthosiphon aristatus Blume Miq

<b>Background and Objective:</b> The cat whiskers plant (<i>Orthosiphon aristatus</i> Blume Miq) is a plant that has been widely used as raw material for traditional medicine. The population of white-purple varieties of <i>O. aristatus</i> is decreasing efforts to maintain the white-purple <i>O. aristatus</i> need to be done keeping in mind its potential as raw material for traditional medicine. This study aims to determine the composition of a suitable medium in growing plantlet <i>O. aristatus</i> white-purple varieties and the content of its secondary metabolites. <b>Materials and Methods:</b> The internode explants were induced on MS medium added by various combinations of zeatin and 2,4-Dichlorophenoxyacetic acid (2,4-D). Root induction was carried out on shoots formed on MS medium with Indole-3-Butyric Acid (IBA). The acclimatization process was carried out using soil media. Determination of secondary metabolite levels was carried out on <i>O. aristatus</i> (<i>in vitro</i> culture) and wild-type plants aged ten months using high-performance liquid chromatography (HPLC). <b>Results:</b> MS+BAP 2ppm+NAA3 ppm media was the optimal medium for growing shoots in leaf explants. Media MS+zeatin 3 ppm+2,4-D 2 ppm produced good shoot growth on internode explants. The best root induction occurred in MS+IBA media of 0.75 ppm. The acclimatization process was successful on shoots originating from the internode, while those from leaf explants had not succeeded in growing and developing. <b>Conclusion:</b> The levels of rosmarinic acid and sinensetin in the white-purple variety <i>O. aristatus</i> (<i>in vitro</i> culture) were 1.08 and 1.62% w/w and higher than those of wild varieties.

Genotype selection for phytochemical content and pharmacological activities in ethanol extracts of fifteen types of Orthosiphon aristatus (Blume) Miq. leaves using chemometric analysis

Orthosiphon aristatus (Blume) Miq. of the Lamiaceae family, called as kumis kucing in Indonesia, is a valuable medicinal plant for their pharmacological properties. The present study comprised of fifteen genotypes of O. aristatus was undertaken to evaluate the genotypes based on phytochemical content and pharmacological activities of leaves ethanol extract. Chemometric analysis (correlation and principal component analysis) was also used to investigate the genetic variability based on phytochemical content and pharmacological activities of O. aristatus genotypes. Results of phytochemical characterization showed that total phenolic ranged from 1.48 to 36.08 (maximum in A15) mg GAE/g DW, total flavonoid ranged from 0.10 to 3.07 (maximum in A15) mg QE/g DW, sinensetin ranged from 0.36 to 4.02 (maximum in A11) mg/g DW, and rosmarinic acid ranged 0.06 to 7.25 (maximum in A7) mg/g DW. Antioxidant activity was tested using DPPH and FRAP assay. Antioxidant results showed that DPPH ranged from 1.68 to 15.55 (maximum in A15) μmol TE/g DW and FRAP ranged from 0.07 to 1.60 (maximum in A1 and A7) μmol TE/g DW. The genotype A8 showed the highest cytotoxic activities against HeLa (66.25%) and MCF-7 (61.79%) cell lines. Maximum α-glucosidase inhibitory activity was recorded in genotype A2 with the value of 62.84%. The genotypes A1, A2, A7, A11, and A15 were identified as superior based on their phytochemicals content and pharmacological activities coupled with chemometric analysis. This finding is important for breeding studies and also the pharmaceutical perspective of O. aristatus.

"Kidney Tea" and Its Bioactive Secondary Metabolites for Treatment of Gout

Clerodendranthus spicatus, popularly known as "kidney tea" in China, is consumed traditionally as a functional food for treatment of renal inflammation, dysuria, and gout. We evaluated the effects of C. spicatus on gout by assessing activities of antihyperuricemia, anti-gouty arthritis, and analgesia in vivo, and the results indicated that the ethyl acetate fraction shows potential activities. Subsequent phytochemical investigation of this fraction led to the isolation of 32 compounds, consisting of 20 diterpenoids (including the new orthosiphonones E and F), 2 triterpenoids, 6 flavonoids, 2 lignanoids, and 2 phenolic acid derivatives. Pharmacological investigation of the pure compounds in the cellular model of hyperuricemia indicated that 12 compounds could promote the excretion of uric acid at 10 μg/mL, and compounds 3, 4, 5, and 21 had better effects than that of benzbromarone, a famous uricosuric drug. Furthermore, compounds 4, 6, 7, 9, 14, 15, 23, 26, and 31 showed significant anti-gouty arthritis activity in monosodium urate (MSU)-induced joint swelling at the dose of 50 mg/kg, while compounds 4, 5, 7, 9, and 26 exhibited significant inhibition of pain induced by acetic acid. Our findings provided scientific justification to support the traditional application of "kidney tea" for treating gout and suggested its good application prospects in the future.

Characterization of polymeric phenolic acids and flavonoids in Clerodendranthi Spicati Herba using ultrahigh-performance liquid chromatography coupled to quadrupole time-of-flight tandem mass spectrometry with target and nontarget data mining strategy

RATIONALE

Clerodendranthi Spicati Herba (CSH) is often used to treat urinary stones, urinary tract infections and nephritis in China. Much literature has reported that polymeric phenolic acids and flavonoids are the major bioactive components in CSH. Therefore, it is very meaningful to identify the polymeric phenolic acids and flavonoids in CSH.

METHODS

Ultrahigh-performance liquid chromatography coupled to quadrupole time-of-flight tandem mass spectrometry (UHPLC/QTOF-MS/MS) analysis with target and nontarget data mining strategy was proposed to rapidly profile the polymeric phenolic acids and flavonoids in CSH. Diagnostic product ions and neutral loss filter were beneficial for identifying the polymeric phenolic acids and flavonoids from complex compounds in CSH.

RESULTS

A total of 118 compounds, including 85 polymeric phenolic acids and 33 flavonoids, were reasonably identified in CSH by comparing their main fragmentation pathways with literature data, and 85 of them were discovered in CSH firstly by nontarget analysis. Nine potential compounds were characterized tentatively as new pentameric and hexameric phenolic acids in CSH. Six types of polymeric phenolic acids (monomer, dimer, trimer, tetramer, pentamer and hexamer) and four types of flavonoids (apigenin, kaempferol, luteolin and quercetin) were identified in CSH.

CONCLUSIONS

The results indicated that the UHPLC/QTOF-MS/MS method coupled with target and nontarget data mining strategy was feasible and rational for identifying the polymeric phenolic acids and flavonoids in complex chemical constituents of CSH. The findings will be conducive to the discovery of the active ingredients of CSH and the establishment of quality standards.

In Vitro Regeneration and ISSR-Based Genetic Fidelity Analysis of Orthosiphon stamineus Benth

Orthosiphon stamineus has been widely used as traditional remedy for various illnesses and diseases, such as cardiovascular diseases and epileptic seizures. In this study, direct regeneration through nodal segment of this species was attempted using Kinetin (6-Furfurylaminopurine) and IAA (indole-3-acetic acid). Optimum regeneration media was identified as MS media supplemented with 2.0 mg L−1 Kin plus 0.5 mg L−1 IAA. This yielded the highest number of shoots (5.57 ± 0.42) and leaves (20.53 ± 1.91) per explant. Acclimatization of the resulting in vitro regenerants was successful in all potting mixtures tested. However, potting mixture PF (1:1:1 ratio of black soil/red soil/compost) was identified as the best medium for acclimatization of this species, as it yielded 100% survival percentage after 90 days of acclimatization. Ten in vitro regenerants of O. stamineus were randomly collected after the third subculture and subjected to genetic variation analysis using inter-simple sequence repeat (ISSR) markers. Out of 20 ISSR markers tested, 10 working primers were observed to produce satisfactory amplification of bands, with an average of 7.11 bands per primer. A total of 610 bands were produced by the 10 primers. The percentage of polymorphism was observed to be very low, yielding only 7.32% polymorphism among all samples. Jaccard dissimilarity analysis was also conducted and very low genetic distance (about 0.1) was found among the in vitro regenerants and between the regenerants with the mother plant, thus ascertaining the clonal nature of the plantlets produced in this study.

Metabolic profile of rosmarinic acid from Java tea (Orthosiphon stamineus) by ultra-high-performance liquid chromatography coupled to quadrupole-time-of-flight tandem mass spectrometry with a three-step data mining strategy

Rosmarinic acid (RA) is a caffeic acid derivative and one of the most abundant and bioactive constituents in Java tea (Orthosiphon stamineus), which has significant biological activities. However, relatively few studies have been conducted to describe this compound's metabolites in vivo. Therefore, an ultra-high-performance liquid chromatography coupled to quadrupole-time-of-flight tandem mass spectrometry (UHPLC-QTOF-MS/MS) analysis with a three-step data mining strategy was established for the metabolic profile of RA. Firstly, the exogenously sourced ions were filtered out by the MarkerView software and incorporated with Microsoft Office Excel software. Secondly, a novel modified mass detects filter strategy based on the predicted metabolites was developed for screening the target ions with narrow, well-defined mass detection ranges. Thirdly, the diagnostic product ions and neutral loss filtering strategy were applied for the rapid identification of the metabolites. Finally, a total of 16 metabolites were reasonably identified in urine, bile and feces, while metabolites were barely found in plasma. The metabolites of RA could also be distributed rapidly in liver and kidney. Glucuronidation, methylation and sulfation were the primary metabolic pathways of RA. The present findings might provide the theoretical basis for evaluating the biological activities of RA and its future application.

Rosmarinic Acid, the Main Effective Constituent of Orthosiphon stamineus, Inhibits Intestinal Epithelial Apoptosis Via Regulation of the Nrf2 Pathway in Mice

Many studies have shown that Orthosiphon stamineus extract (OE) has antioxidant activity, and we previously reported that OE protects the intestine against injury from a high-fat diet. However, the molecular mechanism underlying this protective effect of OE was unclear. Here, OE was separated according to polarity and molecular weight, and the antioxidant activity of each component was compared. The components with the highest antioxidant activity were analyzed by HPLC, which confirmed that rosmarinic acid (RA) was the main effective constituent in OE. OE and RA were then tested in a mouse high-fat diet-induced intestinal injury model. The antioxidant indices and morphological characteristics of the mouse jejunum were measured, and activation of the nuclear factor E2-related factor 2 (Nrf2) pathway and apoptosis of jejunal epithelial cells were analyzed. Of all the constituents in OE, RA contributed the most. Both RA and OE activated the Nrf2 pathway and increased downstream antioxidant enzyme activity. RA and OE protected the mouse intestine against high-fat diet-induced oxidative stress by preventing intestinal epithelial cell apoptosis via both extracellular and intracellular pathways. Thus, RA, the main effective constituent in OE, inhibits intestinal epithelial apoptosis by regulating the Nrf2 pathway in mice.

Stevia residue extract increases intestinal uric acid excretion via interactions with intestinal urate transporters in hyperuricemic mice

The supplementation of STVRE significantly attenuated hyperuricemia and oxidative stress, upregulated ABCG2 and downregulated GLUT9 (protein and mRNA) expression in hyperuricemic mice.

Comparative in vitro studies of the biological potential and chemical composition of stems, leaves and berries Aronia melanocarpa's extracts obtained by subcritical water extraction

Preparation of functional products as well as natural-based products requires non-toxic but effective extraction techniques. In this study, subcritical water extraction was used for the extraction of different aronia parts in order to explore their potential. Stems, leaves and berries of Aronia melanocarpa were extracted under the following conditions: temperature 130 °C; pressure 35 bar; time 20 min. The total phenols and flavonoid contents of the produced extracts were evaluated by conventional spectrophotometric methods. Additionally, the main phenolic compounds were also identified and quantified by high performance liquid chromatography with diode array detection (HPLC-DAD). The biological potential of the extracts was evaluated by determining their antioxidant (DPPH, ABTS and lipid peroxidation assays), antimicrobial, enzyme inhibitory (cholinesterase and elastase) and cytotoxic effects (HeLa, A-549, LS-174T, MRC-5 cell lines). The results indicate that leaves and berries extracts exhibited stronger antioxidant action when compared with stems. The strongest cholinesterase and elastase inhibitory activity was also found in berries extract. Similarly, the extracts obtained from leaves and berries showed considerable cytotoxic effects against tested cell lines. A moderate antimicrobial effects was observed too. Demonstrated biological potential of all three aronia parts can trace a new road map for developing newly designed functional products.