Staminane- and isopimarane-type diterpenes from Orthosiphon stamineus of Taiwan and their nitric oxide inhibitory activity

Isolation, structure modification, and anti-rheumatoid arthritis activity of isopimarane-type diterpenoids from Orthosiphon aristatus

Orthosiphon aristatus is a well-known folkloric medicine and herb for Guangdong soup for the treatment of rheumatism in China. Eight isopimarane-type and migrated pimarane-type diterpenoids (1-8), including a new one with a rarely occurring α,β-unsaturated diketone C-ring, were isolated from O. aristatus. Their structures were determined by spectroscopic methods and quantum chemical calculations. Furthermore, the most abundant compound, orthosiphol K, was structurally modified by modern synthetic techniques to give seven new derivatives (9-15). The anti-rheumatoid arthritis activity of these diterpenoids were evaluated on a TNF-α induced MH7A human rheumatoid fibroblast-like synoviocyte model. Compound 10 showed the most potent activity among these compounds. Based on their inhibitory effects on the release levels of IL-1β, the preliminary structure-activity relationships were concluded. Furthermore, western blot analysis revealed that 10 could increase the expression of IκBα and decrease the expression of NF-κB p65, and the expression levels of COX-2 and NLRP3 proteins were consequently down-regulated.

Asymmetric synthesis of the fully functionalized six-membered A-ring of siphonol A

A synthetic study toward the construction of the fully functionalized six-membered A-ring of siphonol A is described. The salient features include the introduction of a six-membered ring system through a HWE reaction, the construction of a stereocenter at C5 via a hetero-Diels-Alder reaction, and the installation of the fully functionalized six-membered A-ring of siphonol A through photolytic decarboxylation.

A Study of the Medicinal Plants of Genus Orthosiphon sp.: Aiming to Expand Valuable Medicinal Resources for Medical Treatment

<b>Background and Objective:</b> <i>Orthosiphon</i> sp., contains many active ingredients that are beneficial to health. In addition to prevention, they are also used in treatment. This study aims to evaluate the agronomic characteristics of 9 <i>Orthosiphon</i> sp., based on morphology and combine molecular biology methods to determine the genetic relationship based on the "ITS1-4" gene region. <b>Materials and Methods:</b> Nine seed samples/species <i>Orthosiphon</i> sp., grown in 9 provinces in South Vietnam were collected and planted for survey at the Can Tho experimental farm. The method of observing and describing the external morphology and microdissection of the eye cage is carried out. The DNA extraction was performed at the Molecular Biology Laboratory, Institute of Food and Biotechnology, Can Tho University. <b>Results:</b> There are differences in some parameters except leaf width and flower diameter. A simple pedigree chart can classify nine cat breeds into 3 groups: Group I includes An Giang (Râ1), Ca Mau (Râ2) and Can Tho (Râ3) breeds that are genetically close to each other and have only the same quantity, group II includes 2 varieties of Vinh Long (Râ8) and Dong Thap (Râ6), group III includes 4 identical samples in Kien Giang (Râ7), Hau Giang (Râ4), Soc Trang (Râ5) and Tien Giang (Râ9). <b>Conclusion:</b> With molecular biology techniques, 9 cat breeds have been identified, all belonging to the species <i>Orthosiphon aristatus</i>. However, to have more accurate and complete conclusions, it is necessary to study some specific gene sequences related to the morphology and substances contained in the plant.

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.

Rationale of Orthosiphon aristatus for Healing Diabetic Foot Ulcer

Orthosiphon aristatus (Blume) Miq. is traditionally used for wound healing in South East Asia and scientifically proven for its antidiabetic potential. Wounds due to diabetes, especially diabetic foot ulcer (DFU), always involve a complicated healing process. The present work aims to review the information on the rationale of the phytochemicals from O. aristatus in promoting DFU healing. The findings showed that the DFU healing potential of O. aristatus was characterized by a reduction in the blood glucose level, mainly attributed to the significant concentration of constituents such as caffeic acid, rosmarinic acid, and sinensetin in the plant extract. These phytochemicals possibly induce insulin secretion and sensitivity, improve the lipid profile, and stimulate glucose uptake. Furthermore, the healing effect may also be contributed to the antioxidant, anti-inflammatory, and antihyperglycemic properties of the plant. The roles of phytochemicals have been systematically postulated in the 4 phases of the healing process. Moreover, no adverse toxic sign or abnormality has been reported upon oral administration of the plant extract. This suggests that O. aristatus extract could be a potential diabetic wound healing phytomedicine for further preclinical and clinical studies.

"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.

Scrodentoids H and I, a Pair of Natural Epimerides from Scrophularia dentata, Inhibit Inflammation through JNK-STAT3 Axis in THP-1 Cells

Background

Scrophularia dentata is an important medicinal plant and used for the treatment of exanthema and fever in Traditional Tibetan Medicine. Scrodentoids H and I (SHI), a pair of epimerides of C₁₉-norditerpenoids isolated from Scrophularia dentata, could transfer to each other in room temperature and were firstly reported in our previous work. Here, we first reported the anti-inflammatory effects of SHI on LPS-induced inflammation.

Purpose

To evaluate the anti-inflammatory property of SHI, we investigated the effects of SHI on LPS-activated THP-1 cells.

Methods

THP-1 human macrophages were pretreated with SHI and stimulated with LPS. Proinflammatory cytokines IL-1β and IL-6 were measured by RT-PCR and enzyme-linked immunosorbent assays (ELISA). The mechanism of action involving phosphorylation of ERK, JNK, P38, and STAT3 was measured by western Blot. The NF-κB promoter activity was evaluated by Dual-Luciferase Reporter Assay System in TNF-α stimulated 293T cells.

Results

SHI dose-dependently reduced the production of proinflammatory cytokines IL-1β and IL-6. The ability of SHI to reduce production of cytokines is associated with phosphorylation depress of JNK and STAT3 rather than p38, ERK, and NF-κB promoter.

Conclusions

Our experimental results indicated that anti-inflammatory effects of SHI exhibit attenuation of LPS-induced inflammation and inhibit activation through JNK/STAT3 pathway in macrophages. These results suggest that SHI might have a potential in treating inflammatory disease.

Anti-inflammatory activities of isopimara-8(14),-15-diene diterpenoids and mode of action of kaempulchraols P and Q from Kaempferia pulchra rhizomes

Inflammation is an extensively recognized link to many pathological diseases. It is a host response for protection from infections and tissue damage. Infections trigger acute inflammation; however, persistent infection will contribute to chronic inflammation and higher disease susceptibility. Deregulated inflammatory responses can cause excessive or long-lasting tissue damage, manifested as cancer, immune disorders, diabetes, etc. NF-κB is a central mediator of pro-inflammatory gene induction and functions in both innate and adaptive immune cells; therefore, the anti-inflammatory regulation of NF-κB is needed. Natural products reportedly play an important role in controlling the inflammatory response pathways. However, the anti-inflammatory activities of isopimara-8-(14),15-diene diterpenoids have not yet been fully elucidated. To elucidate the anti-inflammatory activities of the isopimara-8(14),15-diene diterpenoids, we investigated 21 isopimara-8(14),15-diene diterpenoids previously isolated from Kaempferia pulchra rhizomes. Eleven compounds exhibited NO inhibitory activity against lipopolysaccharide (LPS)-induced RAW264.7 cells, with IC₅₀ values ranging from 30 to 100 μM. Furthermore, the most potent kaempulchraols P and Q, with IC₅₀ values of 39.88 and 36.05 μM, respectively, inhibited the NF-κB-mediated transactivation of a luciferase reporter gene, IL-6 production, and COX-2 expression, with an effective dose of 25 μM. These findings provide new insights into the anti-inflammatory activities of the isopimara-8(14),15-diene diterpenoids.

Polymethoxylated flavones from Orthosiphon stamineus leaves as antiadhesive compounds against uropathogenic E. coli

Aqueous and acetone extracts of O. stamineus leaves reduce the adhesion of uropathogenic E. coli (UPEC, strain UTI89) to T24 bladder cells significantly (IC₂₅ ~ 524 mg/mL, resp. 40 μg/mL). The acteonic extract had no cytotoxic effects against UPEC in concentrations that inhibited the bacterial adhesion. The extract significantly reduced the gene expression of fimH, fimC, fimD, csgA and focG, which are strongly involved in the formation of bacterial adhesins. The antiadhesive effect was due to the presence of polymethoxylated flavones, enriched in the acetonic extract. Five flavones have been isolated by fast centrifugal partition chromatography, followed by preparative HPLC. Eupatorin, ladanein, salvigenin, sinensetin, 5,6,7,4'-tetramethoxyflavone and 5-hydroxy-6,7,3',4'-tetramethoxyflavone were identified as the main polymethoxylated flavones. With the exception of eupatorin, all of these flavones reduced the bacterial adhesion in a concentration depending manner, indicating that B-ring hydroxylation and methoxylation seems to have a major impact on the antiadhesive activity. In addition, this was confirmed by investigation of the flavones chrysoeriol and diosmetin, which had only very weak antiadhesive activity. From these data, Orthosiphon extracts can be assessed to have a pronounced antiadhesive activity against UPEC, based on a variety of polymethoxylated flavones.

Qualitative and quantitative analysis on the chemical constituents in Orthosiphon stamineus Benth. using ultra high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry

A sensitive and efficient method was established and validated for qualitative and quantitative analysis on the chemical constituents in Orthosiphon stamineus Benth. (O. stamineus) using ultra high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry. Based on the retention time and MS spectra, 61 compounds were detected by using ultra high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry. 52 chemical structures in the O. stamineus extracts including 26 phenolic acids, 11 flavonoids, 6 diterpenoids, 4 fatty acids and 5 tanshinones were tentatively identified without the time-consuming process of isolation. Moreover, five chemical constituents (Danshensu, Caffeic acid, Rosmarinic acid, Sinensetin and Eupatorin) were quantified in three different batches of O. stamineus samples by the developed ultra high-performance liquid chromatography coupled with electrospray ionization triple-quadrupole mass spectrometry method in 10 min. The method validation of the five compounds was performed with acceptable linearity (R², 0.9930-0.9997), precision (RSD, 1.87-10.36%), repeatability (RSD, 0.59-4.87%) and recovery (105.30-110.53%, RSD ≤ 13.90%).

Orthosiphon stamineus Benth. is an Outstanding Food Medicine: Review of Phytochemical and Pharmacological Activities

Orthosiphon stamineus Benth. (Lamiaceae) is a valued medicinal plant in traditional folk medicine. Many pharmacological studies have demonstrated the ability of this plant to exhibit antimicrobial, antioxidant, hepatoprotection, antigenotoxic, antiplasmodial, cytotoxic, cardioactive, antidiabetic, anti-inflammatory activies. This review is a comprehensive summary of the presently available chemical, pharmacological investigations as well as the traditional and therapeutic uses of this plant. Important and different experimental data have been addressed along with a review of all phytochemicals identified in this plant, including flavonoids, terpenoids, and essential oils. O. stamineus has wide traditional and pharmacological uses in various pathophysiological conditions. Therefore, it is an attractive subject for further experimental and clinical investigations.

Phenolic acid derivatives with neuroprotective effect from the aqueous extract of Clerodendranthus spicatus

Two new phenolic acid helisterculins C (1) and D (2) were isolated from the whole plant of Clerodendranthus spicatus. Their structures were elucidated on the basis of 1D and 2D NMR, MS, and CD analysis. Compound 1 possesses an unusual bicyclol [2. 2. 2] octane moiety which is rare in the previously isolated phenolic acid derivatives. The two compounds were tested in vitro for neuroprotective activities against 6-OHDA-induced cell death in SH-SY5Y cells, and the result showed that compounds 1 and 2 displayed moderate neuroprotective activity with the IC₅₀ values of 17.4 and 21.3 μM, respectively.

Aqueous extract from Orthosiphon stamineus leaves prevents bladder and kidney infection in mice

BACKGROUND

Extracts from the leaves of Orthosiphon stamineus are used in phytotherapy for treatment of uncomplicated urinary tract infections.

PURPOSES

Evaluation of an aqueous extract against infection with uropathogenic Escherichia coli in vivo; investigation of underlying microbiological mechanisms.

STUDY DESIGN

In vivo studies in mice and in vitro investigations on cytotoxicity, antiadhesive potential, influence on bacterial gene expression and quorum sensing.

METHODS

Extract OWE was prepared by hot water extraction. For in vivo studies BALB/c mice were used in an UPEC infection model. The effect of OWE on bacterial load in bladder/kidney tissue was monitored in pre- and posttreatment. Cytotoxicity of OWE against different UPEC strains, T24 bladder/A498 kidney cells, gene expression analysis, monitoring of phenotypic motility and quorum sensing was investigated by standard methods of microbiology.

RESULTS

OWE was quantified (UHPLC) according to the content of rosmarinic acid, cichoric acid, caffeic acid. Three- and 5-day treatment of animals with OWE (750mg/kg) after transurethral infection with UPEC CFT073 reduced the bacterial load in bladder and kidney, similar to norfloxacin. Four- and 7-day pretreatment of mice prior to the infection with UPEC NU14 reduced bacterial bladder colonization. In vitro investigations indicated that OWE (≤2mg/ml) has no cytotoxic or proliferation-inhibiting activity against different UPEC strains as well as against T24 bladder and A498 kidney cells. OWE exerts a dose dependent antiadhesive activity against UPEC strains NU14 and UTI89. OWE reduced gene expression of fimH, but evoked increase of the expression of motility/fitness gene fliC. Increase of bacterial motility on gene level was confirmed by a changed bacterial phenotype by an increased bacterial motility in soft agar assay. OWE inhibited in a concentration-dependent manner bacterial quorum sensing.

CONCLUSION

OWE is assessed as a strong antiadhesive plant extract for which the traditional use in phytotherapy for UTI might be justified.

Clerodendranoic acid, a new phenolic acid from Clerodendranthus spicatus

Phenolic acid derivatives are typical constituents of Clerodendranthus spicatus which were considered to the active principles of this medicinal plant. These chemical constituents with their interesting frameworks and biological significance attracted our attention. As part of our ongoing chemical investigation of C. spicatus using various column chromatography techniques, a new phenolic compound, named clerodendranoic acid (1), was isolated from the aerial parts of C. spicatus together with five known ones, including rosmarinic acid (2), methyl rosmarinate (3), caffeic acid (4), methyl caffeate (5), ethyl caffeate (6). Their structures, including stereochemical configurations, were completely established by extensive spectroscopic methods, mainly inclvolving 1D, 2D NMR, as well as HRESIMS.

Ethnobotanical approach versus random approach in the search for new bioactive compounds: support of a hypothesis

CONTEXT

Whether natural product drug discovery programs should rely on wild plants collected "randomly" from the natural environment, or whether they should also include plants collected on the basis of use in traditional medicine remains an open question.

OBJECTIVE

This study analyzes whether plants with ethnomedical uses from Vietnam and Laos have a higher hit rate in bioassay testing than plants collected from a national park in Vietnam with the goal of maximizing taxonomic diversity ("random" collection).

MATERIALS AND METHODS

All plants were extracted and subjected to bioassay in the same laboratories. Results of assays of plant collections and plant parts (samples) were scored as active or inactive based on whether any extracts had a positive result in a bioassay. Contingency tables were analyzed using χ(2) statistics.

RESULTS

Random collections had a higher hit rate than ethnomedical collections, but for samples, ethnomedical plants were more likely to be active. Ethnomedical collections and samples had higher hit rates for tuberculosis, while samples, but not collections, had a higher hit rate for malaria. Little evidence was found to support an advantage for ethnomedical plants in HIV, chemoprevention and cancer bioassays. Plants whose ethnomedical uses directly correlated to a bioassay did not have a significantly higher hit rate than random plants.

DISCUSSION

Plants with ethnomedical uses generally had a higher rate of activity in some drug discovery bioassays, but the assays did not directly confirm specific uses.

CONCLUSIONS

Ethnomedical uses may contribute to a higher rate of activity in drug discovery screening.

Clinically useful anticancer, antitumor, and antiwrinkle agent, ursolic acid and related derivatives as medicinally important natural product

Medicinal plants are becoming an important research area for novel and bioactive molecules for drug discovery. Novel therapeutic strategies and agents are urgently needed to treat different incurable diseases. Many plant derived active compounds are in human clinical trials. Currently ursolic acid is in human clinical trial for treating cancer, tumor, and skin wrinkles. This review includes the clinical use of ursolic acid in various diseases including anticancer, antitumor, and antiwrinkle chemotherapies, and the isolation and purification of this tritepernoid from various plants to update current knowledge on the rapid analysis of ursolic acid by using analytical methods. In addition, the chemical modifications of ursolic acid to make more effective and water soluble derivatives, previous and current information regarding, its natural and semisynthetic analogs, focusing on its anticancer, cytotoxic, antitumor, antioxidant, anti-inflammatory, anti-HIV, acetyl cholinesterase, α-glucosidase, antimicrobial, and hepatoprotective activities, briefly discussion is attempted here for its research perspectives. This review article contains fourteen medicinally important ursolic acid derivatives and 351 references.