Two new benzylbenzoate glucosides from Curculigo orchioides

Curculigoside attenuates osteoporosis through regulating DNMT1 mediated osteoblast activity

This work aims to study the function of curculigoside in osteoporosis and explore whether DNMT1 is closely involved in osteoblast activity. After OB-6 osteoblasts were treated with hydrogen peroxide (H2O2), a curculigoside treatment group was set up and a series of biological tests including MTT, flow cytometry, western blotting, ROS fluorescence intensity, mitochondrial membrane potential, and ELISA experiments were performed to verify the effect of curculigoside on the activity of osteoblasts. Then, alkaline phosphatase (ALP) activity, alizarin red staining, PCR, and western blotting assays were performed to detect the effects of curculigoside on osteoblast function. By constructing DNMT1 knockdown and overexpression OB-6 cell lines, the effect of DNMT1 on osteoblast function was verified. In addition, the expression level of Nrf2 in each group was detected to speculate the mechanism of DNMT1 in osteoporosis. The cell activity and level of bcl-2 and SOD were significantly increased; the cell apoptosis, ROS fluorescence intensity, mitochondrial membrane potential, MDA and level of caspase-3, Bax, and CAT was reduced in curculigoside treatment group compared with H2O2-induced OB-6 osteoblasts. Meanwhile, the ALP activity, number and area of bone mineralized nodules, and gene and protein expression of OSX and OPG were significantly elevated in curculigoside group. Moreover, DNMT1 knockdown had a similar promotion effect on osteoblast function as curculigoside, and DNMT1 overexpression could reverse the promotion effect of curculigoside on osteoblast function. Further mechanistic studies speculated that DNMT1 might play a role in osteoporosis by affecting Nrf2 methylation. Curculigoside enhances osteoblast activity through DNMT1 controls of Nrf2 methylation.

Curculigo orchioides Gaertn.: An Overview of Its Effects on Human Health

Curculigo orchioides, commonly called “Kali Musli,” is an endangered medicinal plant commonly found in Asian countries such as India, Japan, China, and Nepal. The plant holds a significant position in Ayurvedic and the Chinese traditional medicine system; it is documented as an aphrodisiac herb. The plant is also reported to be used in the treatment for asthma and jaundice. The botany, traditional uses, phytochemistry, and pharmacological activities to evaluate the plant's importance and relevant information are reviewed and summarized. We discern that a total of 61 phytochemicals are identified and reported in C. orchioides. These belong to the various phytochemical group of glycosides, lignans, polysaccharides, alkaloids, saponins, triterpenes, and aliphatic compounds. The most explored bioactive compound is a phenolic glycoside, curculigoside, isolated from the plant's rhizome. In vitro and in vivo research is conducted globally to provide primary and robust evidence to support this herbal medicine's traditional uses. A large lacuna regarding the mechanisms involved in the biological activity of the plant is evident. There is a need to conduct in-depth studies to understand the relationship between traditional and modern pharmacological uses of C. orchioides.

Characterization of the complete chloroplast genome of medical plant Curculigo orchioides Gaertn. (Amaryllidaceae)

Curculigo orchioides Gaertn. distributed in subtropical regions of Asia including southern China and India. The plant is used as a traditional medicine in China for the treatment of menorrhagia, osteoporosis, and other gynecological problems. The complete chloroplast genome was reported in this study using the Illumina NovaSeq platform. The whole genome of this species was 157,472 bp in length, with a total GC content of 37.44%. The large single copy (LSC) was 86,507 bp, the small single copy (SSC) was 16,867 bp, and both of the two inverted repeats (IRs) were 27,049 bp, respectively. A total of 132 unique genes were identified, among which are 86 protein-coding genes, 38 tRNA genes and 8 rRNA genes. The phylogenetic analysis revealed that C. orchioides was highly clustered with C. capitulata. Our study will provide useful fundamental data for further phylogenetic and evolutionary studies of C. orchioides.

Pharmacokinetic and Metabolism Studies of Curculigoside C by UPLC-MS/MS and UPLC-QTOF-MS

Pharmacokinetic and metabolism studies were carried out on curculigoside C (CC), a natural product with good antioxidant and neuroprotective effects, with the purpose of investigating the effects of the hydroxyl group at C-3' in curculigoside. A rapid and sensitive method with UPLC-MS was developed and fully validated for the first time in the pharmacokinetic analysis for quantification of CC in rat plasma. The assay was linear (R² > 0.9984) over the concentration range of 1⁻2500 ng/mL, with the lower limit of quantification (LLOQ) being 1 ng/mL. The intra-day and inter-day precision (expressed as relative standard deviation, RSD) ranged from 4.10% to 5.51% and 5.24% to 6.81%, respectively. The accuracy (relative error, RE) ranged from -3.28% to 0.56% and -5.83% to -1.44%, respectively. The recoveries ranged from 92.14% to 95.22%. This method was then applied to a pharmacokinetic study of rats after intragastric administration of 15, 30 and 60 mg/kg CC. The results revealed that CC exhibited rapid oral absorption (Tmax = 0.106 h, 0.111 h, and 0.111 h, respectively), high elimination (t1/2 = 2.022 h, 2.061 h, and 2.048 h, respectively) and low absolute bioavailability (2.01, 2.13, and 2.39%, respectively). Furthermore, an investigation on the metabolism of CC was performed by UPLC-QTOF-MSE. Twelve metabolites of CC from plasma, bile, urine and faeces of rats were confirmed. The main metabolic pathways of CC, which involve dehydration, glucosylation, desaturation, formylation, cysteine conjugation, demethylation and sulfonation, were profiled. In conclusion, this research has developed a sensitive quantitative method and demonstrated the metabolism of CC in vivo.

Medicinal plants of genus Curculigo: traditional uses and a phytochemical and ethnopharmacological review

ETHNOPHARMACOLOGICAL RELEVANCE

In the genus Curculigo, Curculigo orchioides Gaertn, Curculigo capitulata (Lour) O. Ktze and Curculigo pilosa (Schumach. & Thonn.) Engl are often used in traditional medicine. Curculigo orchioides is used for the treatment of impotence, limb limpness, arthritis of the lumbar and knee joints, and watery diarrhea in traditional Chinese medicine, and also used as a potent immunomodulator and aphrodisiac in the Ayurvedic medical system. Curculigo capitulata is used for the treatment of consumptive cough, kidney asthenia, impotence and spermatorrhea, hemorrhoids, asthma, jaundice, diarrhea, colic and gonorrhea in traditional Chinese and India medicine, and to treat urinary tract infection, acute renal pelvis and nephritis, nephritis-edema, cystitis, nephrolithiasis, hypertension and rheumatic arthritis in traditional Dai medicine. Curculigo pilosa are applied to treat gastrointestinal and heart diseases in Africa.

AIM OF THE REVIEW

This review aims to exhibit up-to-date and comprehensive information about traditional uses, phytochemistry, pharmacology and toxicology of medicinal plants in the genus Curculigo, and has an insight into the opportunities for the future research and development of Curculigo plant.

METHODS

A bibliographic investigation was performed by analyzing the information available on Curculigo plant from worldwide accepted scientific databases (Pubmed, Scopus and Web of Science, SciFinder, Google Scholar, Yahoo). Furthermore, information also was obtained from some local and foreign books on ethnobotany and ethnomedicines.

RESULTS

Curculigo orchioides, Curculigo capitulata and Curculigo pilosa have been used as traditional medicine to treat kinds of diseases such as impotence, limb limpness, gastrointestinal and heart diseases, etc. Phytochemical investigation of eight species of the genus Curculigo has resulted in identification of more than 110 compounds. The content of curculigoside is used as an indicator to evaluate the quality of rhizome of Curculigo orchioides. The medicinal plants have showed a wide spectrum pharmacological activities, including adaptive, immunostimulatory, taste-modifying and sweet-tasting, antioxidant, mast cell stabilization, antihistaminic and antiasthmatic, hepatoprotective and neuroprotective activity. Toxicological test indicated that Curculigo orchioides at the dose of 120 g/kg after administrating rats for 180 days may cause injury of liver and kidney.

CONCLUSION

The medicinal plants of genus Curculigo have emerged as a good source of the traditional medicines. Some uses of these plants in the traditional medicines have been validated by pharmacological investigation. However, the mechanism of their actions should be further elucidated; the particular constituent responsible for toxicity should be isolated and identified, and the target tissue and mechanism of toxic ingredients also deserve to be further investigated; more reference substances should be prepared, and sophisticated analytical technologies should be developed to comprehensively assess the quality of Curculigo herbs. These investigations will be helpful for further utilization of the plants of genus Curculigo.

Phenolic glycosides from Curculigo orchioides Gaertn

Five new chlorophenolic glucosides, curculigine E (1), curculigine F (2), curculigine G (3), curculigine H (5), curculigine I (6) and one new phenolic glycoside, orcinoside H (4), together with eight known phenolic glycosides (7-14) were isolated from the Curculigo orchioides Gaertn. Their structures were established by spectroscopic techniques (IR, UV, MS, 1D and 2D NMR). The isolated phenolic glycosides were evaluated for antiosteoporotic activity against MC3T3-E1 cell line using MTT assays. Compounds 1, 2, 3, and 5 showed moderate antiosteoporotic activity with the proliferation rate of 10.1-14.1%.

A new hepatotoxic triterpenoid ketone from Curculigo orchioides

To investigate hepatotoxic constituents, a new cycloartane-type triterpenoid ketone together with four known components was isolated from rhizomes of Curculigo orchioides. The structures of five compounds were elucidated on the basis of spectroscopic methods, including 1D and 2D NMR, and single-crystal X-ray diffraction analysis. Their hepatotoxicity effects in human hepatic cell line HL-7702 were tested for the first time.

Antiosteoporotic activity of phenolic compounds from Curculigo orchioides

Six phenolic compounds isolated from Curculigo orchioides, including 2,6-dimethoxy benzoic acid (1), curculigoside A (2), curculigoside B (3), curculigine A (4), curculigine D (5) and 3,3',5,5'-tetramethoxy-7,9':7',9-diepoxylignan-4,4'-di-O-beta-D-glucopyranoside (6), together with the ethanol extract of Curculigo orchioides were evaluated for their activity on osteoblasts in neonatal rat calvaria cultures and multinucleated osteoclasts derived from rat marrow cells so as to characterize the antiosteoporotic components of this plant and explore the relationship of chemical structure with antiosteoporotic activity. The proliferation of osteoblast was assayed by MTT methods. The activity of ALP (alkaline phosphatase) and TRAP (tartrate-resistant acid phosphatase) was measured by p-nitrophenyl sodium phosphate assay. The TRAP stain was used to identify osteoclast in morphology. The resorption pit area on the bone slices formed by osteoclast was measured by computer image processing. The ethanol extract exhibited stimulatory effect on both the osteoblast proliferation and the ALP activity. Six compounds all increased the osteoblast proliferation, and compounds (1), (2) and (4) also slightly increased the osteoblastic ALP activity. Compounds (1), (2), (3), (6) and the ethanol extract decreased area of bone resorption pit, osteoclastic formation and TRAP activity. These results indicated that phenolic compounds are antiosteoporotic chemical constituents from Curculigo orchioides, and their activities are related with chemical structures.

The effects of Rhizoma Curculiginis and Rhizoma Drynariae extracts on bones

Background

Rhizoma Curculiginis (Xianmao) and Rhizoma Drynariae (Gusuibu) are 'Yang-tonifying' traditional Chinese herbal medicines used to strengthen bones. This investigation aims to assess the systemic effect of extracts of Rhizoma Curculiginis and Rhizoma Drynariae on bone histomorphology and formation, and their local effect on bone healing.

Methods

For the investigation of the systemic effect, thirty 8-week-old male BALB/c mice were divided into three groups: (1) control group, ten mice fed daily with distilled water; (2) Rhizoma Curculiginis group, ten mice fed daily with distilled water mixed with Rhizoma Curculiginis extract; (3) Rhizoma Drynarie group, ten mice fed daily with distilled water mixed with Rhizoma Drynarie extract. The mice were fed for five weeks before sacrifice. Twenty micro-tomographic slices with an increment of 0.25 mm were prepared to cover the proximal end of the left tibia of each mouse. Quantitative morphometry of the bone structure was performed. For the investigation of the local effect on bone healing, two bone defects (5 × 10 mm) were created in the parietal bone of each of the three New Zealand white rabbits. Two defects in the first animal were grafted with collagen matrix with Rhizoma Curculiginis extract; two defects in the second animal were grafted with collagen matrix with Rhizoma Drynarie extract; two defects in the third (control) animal were grafted with collagen matrix alone. The animals were sacrificed on day 14 and the defects were dissected and prepared for histological and ultrastructural assessment.

Results

Rhizoma Curculiginis and Rhizoma Drynariae extracts altered the bone histomorphology, both increasing the trabecular number by 10% (P = 0.002). Rhizoma Curculiginis extract increased bone density by 3.13% (P = 0.122) and Rhizoma Drynariae extract increased bone density by 6.45% (P = 0.005). Both Rhizoma Curculiginis and Rhizoma Drynariae extracts induced new bone formation on the margins of the defects.

Conclusion

Two 'Yang-tonifying' herbs, Rhizoma Curculiginis and Rhizoma Drynariae, were demonstrated to have systemic effects on bone histomorphology and formation as well as local bone healing.