Integrated Network Pharmacology and Experimental Validation Approach to Investigate the Mechanisms of Radix Rehmanniae Praeparata - Angelica Sinensis - Radix Achyranthis Bidentatae in Treating Knee Osteoarthritis.

Background: Knee osteoarthritis (KOA) is a persistent degenerative condition characterized by the deterioration of cartilage. The Chinese herbal formula Radix Rehmanniae Praeparata- Angelica Sinensis-Radix Achyranthis Bidentatae (RAR) has often been used in effective prescriptions for KOA as the main functional drug, but its underlying mechanism remains unclear. Therefore, network pharmacology and verification experiments were employed to investigate the impact and mode of action of RAR in the treatment of KOA. Methods: The destabilization of the medial meniscus model (DMM) was utilized to assess the anti-KOA effect of RAR by using gait analysis, micro-computed tomography (Micro-CT), and histology. Primary chondrocytes were extracted from the rib cartilage of a newborn mouse. The protective effects of RAR on OA cells were evaluated using a CCK-8 assay. The antioxidative effect of RAR was determined by measuring reactive oxygen species (ROS), superoxide dismutase (SOD), and glutathione (GSH) production. Furthermore, network pharmacology and molecular docking were utilized to propose possible RAR targets for KOA, which were further verified through experiments. Results: In vivo, RAR significantly ameliorated DMM-induced KOA characteristics, such as subchondral bone sclerosis, cartilage deterioration, gait abnormalities, and the degree of knee swelling. In vitro, RAR stimulated chondrocyte proliferation and the expression of Col2a1, Comp, and Acan. Moreover, RAR treatment significantly reduced ROS accumulation in an OA cell model induced by IL-1ß and increased the activity of antioxidant enzymes (SOD and GSH). Network pharmacology analysis combined with molecular docking showed that Mapk1 might be a key therapeutic target. Subsequent research showed that RAR could downregulate Mapk1 mRNA levels in IL-1ß-induced chondrocytes and DMM-induced rats. Conclusion: RAR inhibited extracellular matrix (ECM) degradation and oxidative stress response via the MAPK signaling pathway in KOA, and Mapk1 may be a core target.

High-Performance Thin-Layer Chromatography Coupled with Single Quadrupole: Application the Identification and Differentiation of Rehmanniae Radix and Its Different Processing Products from Raw Materials to Commercial Products.

The authentication of ingredients in formulas is crucial yet challenging, particularly for constituents with comparable compositions but vastly divergent efficacy. Rehmanniae Radix and its derivatives are extensively utilized in food supplements, which contain analogous compositions but very distinct effects. Rehmanniae Radix, also a difficult-to-detect herbal ingredient, was chosen as a case to explore a novel HPTLC-QDa MS technique for the identification of herbal ingredients in commercial products. Through systematic condition optimization, including thin layer and mass spectrometry, a stable and reproducible HPTLC-QDa MS method was established, which can simultaneously detect oligosaccharides and iridoids. Rehmannia Radix and its processed products were then analyzed to screen five markers that could distinguish between raw and prepared Rehmannia Radix. An HPTLC-QDa-SIM method was further established for formula detection by using the five markers and validated using homemade prescriptions and negative controls. Finally, this method was applied to detect raw and prepared Rehmannia Radix in 12 commercial functional products and supplements.

Catalpol attenuates ischemic stroke by promoting neurogenesis and angiogenesis via the SDF-1α/CXCR4 pathway.

BACKGROUND: Stroke is a leading cause of disability and death worldwide. Currently, there is a lack of clinically effective treatments for the brain damage following ischemic stroke. Catalpol is a bioactive compound derived from the traditional Chinese medicine Rehmannia glutinosa and shown to be protective in various neurological diseases. However, the potential roles of catalpol against ischemic stroke are still not completely clear. PURPOSE: This study aimed to further elucidate the protective effects of catalpol against ischemic stroke. METHODS: A rat permanent middle cerebral artery occlusion (pMCAO) and oxygen-glucose deprivation (OGD) model was established to assess the effect of catalpol in vivo and in vitro, respectively. Behavioral tests were used to examine the effects of catalpol on neurological function of ischemic rats. Immunostaining was performed to evaluate the proliferation, migration and differentiation of neural stem cells (NSCs) as well as the angiogenesis in each group. The protein level of related molecules was detected by western-blot. The effects of catalpol on cultured NSCs as well as brain microvascular endothelial cells (BMECs) subjected to OGD in vitro were also examined by similar methods. RESULTS: Catalpol attenuated the neurological deficits and improved neurological function of ischemic rats. It stimulated the proliferation of NSCs in the subventricular zone (SVZ), promoted their migration to the ischemic cortex and differentiation into neurons or glial cells. At the same time, catalpol increased the cerebral vessels density and the number of proliferating cerebrovascular endothelial cells in the infracted cortex of ischemic rats. The level of SDF-1α and CXCR4 in the ischemic cortex was found to be enhanced by catalpol treatment. Catalpol was also shown to promote the proliferation and migration of cultured NSCs as well as the proliferation of BMECs subjected to OGD insult in vitro. Interestingly, the impact of catalpol on cultured cells was inhibited by CXCR4 inhibitor AMD3100. Moreover, the culture medium of BMECs containing catalpol promoted the proliferation of NSCs, which was also suppressed by AMD3100. CONCLUSION: Our data demonstrate that catalpol exerts neuroprotective effects by promoting neurogenesis and angiogenesis via the SDF-1α/CXCR4 pathway, suggesting the therapeutic potential of catalpol in treating cerebral ischemia.

Exploration of the Dynamic Variations of the Characteristic Constituents and the Degradation Products of Catalpol during the Process of Radix Rehmanniae.

Radix Rehmanniae (RR), a famous traditional Chinese medicine (TCM) widely employed in nourishing Yin and invigorating the kidney, has three common processing forms in clinical practice, including fresh Radix Rehmanniae (FRR), raw Radix Rehmanniae (RRR), and processed Radix Rehmanniae (PRR). However, until now, there has been less exploration of the dynamic variations in the characteristic constituents and degradation products of catalpol as a representative iridoid glycoside with the highest content in RR during the process from FRR to PRR. In this study, an ultra-performance liquid chromatography coupled with photodiode array detector (UPLC-PDA) method was successfully established for the simultaneous determination of ten characteristic components to explore their dynamic variations in different processed products of RR. Among them, iridoid glycosides, especially catalpol, exhibited a sharp decrease from RRR to PRR. Then, three degradation products of catalpol were detected under simulated processing conditions (100 °C, pH 4.8 acetate buffer solution), which were isolated and identified as jiofuraldehyde, cataldehyde, and norviburtinal, respectively. Cataldehyde was first reported as a new compound. Moreover, the specificity of norviburtinal in self-made PRR samples was discovered and validated, which was further confirmed by testing in commercially available PRR samples. In conclusion, our study revealed the decrease in iridoid glycosides and the production of new degradation substances during the process from FRR to PRR, which is critical for unveiling the processing mechanism of RR.

Seven new pentasaccharides from the roots of Rehmannia glutinosa.

Seven new pentasaccharides (1-7), rehmaglupentasaccharides A-G, were isolated from the air-dried roots of Rehmannia glutinosa. Their structures were established from the spectroscopic data obtained and by chemical evidence. The known verbascose (8) and stachyose (9) were also obtained in the current investigation, and the structure of stachyose was unequivocally defined using X-ray diffraction data. Compounds 1-9 were tested for their cytotoxicity against five human tumor cell lines, influence on dopamine receptor activation, and proliferation effects against Lactobacillus reuteri.

Four new iridoid glycosides from the roots of Rehmannia glutinosa.

Four new iridoid glycosides (1-4), rehmaglutosides L-O, were isolated from the air-dried roots of Rehmannia glutinosa. Their structures were established from the spectroscopic data obtained and by chemical evidence. The known mellittoside (5) and ajugol (6) were also obtained in the current investigation, and the structure of mellittoside was unequivocally defined using X-ray diffraction data. Compounds 1-6 were tested for their cytotoxicity against five human tumor cell lines and proliferation effects on Lactobacillus Reuteri.

Anti-aging activities of Rehmannia glutinosa Libosch. crude polysaccharide in Caenorhabditis elegans based on gut microbiota and metabonomic analysis.

Aging is a degenerative progress, accompanied by oxidative damage, metabolic disorders and intestinal flora imbalance. Natural macromolecular polysaccharides have shown excellent anti-aging and antioxidant properties, while maintaining metabolic and intestinal homeostasis. The molecular weight, monosaccharide composition, infrared spectrum and other chemical structure information of four Rehmannia glutinosa polysaccharides (RG50, RG70, RG90, RGB) were determined, and their free radical scavenging ability was assessed. Molecular weight and monosaccharide composition analysis exhibited that RG50 (2-72 kDa), RG70 (3.2-37 kDa), RG70 (3-42 kDa), and RGB (3.1-180 kDa) were heteropolysaccharide with significant different monosaccharide species and molar ratios. We found that RG70 had the best antioxidant activity in vitro and RG70 could enhance the antioxidant enzyme system of Caenorhabditis elegans, diminished lipofuscin and reactive oxygen species levels, up-regulate the expression of daf-16, skn-1 and their downstream genes, and down-regulate the expression of age-1. Metabolomics results showed that RG70 mainly influenced glycine, serine and threonine metabolism and citric acid cycle. 16S rRNA sequencing showed that RG70 significantly up-regulated the abundance of Lachnospiraceae_NK4B4_group, which were positively correlated with amino acid metabolism and energy cycling. These results suggest that RG70 may delay aging by enhancing antioxidant effects, affecting probiotics and regulating key metabolic pathways.

Identification of raffinose family oligosaccharides in processed Rehmannia glutinosa Libosch using matrix-assisted laser desorption/ionization mass spectrometry image combined with machine learning.

RATIONALE: Currently, research on oligosaccharides primarily focuses on the physiological activity and function, with a few studies elaborating on the spatial distribution characterization and variation in the processing of Rehmannia glutinosa Libosch. Thus, imaging the spatial distributions and dynamic changes in oligosaccharides during the steaming process is significant for characterizing the metabolic networks of R. glutinosa. It will be beneficial to characterize the impact of steaming on the active ingredients and distribution patterns in different parts of the plant. METHODS: A highly sensitive matrix-assisted laser desorption/ionization mass spectrometry image (MALDI-MSI) method was used to visualize the spatial distribution of oligosaccharides in processed R. glutinosa. Furthermore, machine learning was used to distinguish the processed R. glutinosa samples obtained under different steaming conditions. RESULTS: Imaging results showed that the oligosaccharides in the fresh R. glutinosa were mainly distributed in the cortex and xylem. As steaming progressed, the tetra- and pentasaccharides were hydrolyzed and diffused gradually into the tissue section. MALDI-MS profiling combined with machine learning was used to identify the processed R. glutinosa samples accurately at different steaming intervals. Eight algorithms were used to build classification machine learning models, which were evaluated for accuracy, precision, recall, and F1 score. The linear discriminant analysis and random forest models performed the best, with prediction accuracies of 0.98 and 0.97, respectively, and thus can be considered for identifying the steaming durations of R. glutinosa. CONCLUSIONS: MALDI-MSI combined with machine learning can be used to visualize the distribution of oligosaccharides and identify the processed samples after steaming for different durations. This can enhance our understanding of the metabolic changes that occur during the steaming process of R. glutinosa; meanwhile, it is expected to provide a theoretical reference for the standardization and modernization of processing in the field of medicinal plants.

Rehmannia Glutinosa Polysaccharide Regulates Bone Marrow Microenvironment via HIF-1α/NF-κB Signaling Pathway in Aplastic Anemia Mice.

Aplastic anemia (AA), a rare disorder, is associated with bone marrow microenvironment (BMM). Presently, AA treatment is of great difficulty. This study aimed to explore the mechanism of action of Rehmannia glutinosa polysaccharide (RGP) in AA. Busulfan was used to induce AA in BALB/c mice; blood cell count and Ray's Giemsa staining were used to assess the severity of hematopoietic failure; HE was performed to assess the pathological state of the marrow cavity; ELISA was performed to assess IL-4, IL-10, IL-6, IL-12, IL-1ß, TNF-α, MCP-1, VEGF, and EPO; and WB was performed to evaluate the effects of RGP on the HIF-1α/NF-κB signaling. Significant downregulation of hemocyte levels in the blood and nucleated cells in the bone marrow was reversed by RGP and Cyclosporine A (CA). Compared with the AA group, dilating blood sinusoids, inflammation, hematopoiesis, decreased bone marrow cells and megakaryocytes were alleviated by RGP and CA, and the HIF-1α/NF-κB signaling was inhibited too. Notably, RGP was more effective when used in combination with CA. In this study, we established a relationship between BMM and the HIF-1α/NF-κB signaling pathway and found that RGP regulates BMM by suppressing the activation of the HIF-1α/NF-κB signaling. Thus, RGP exerts a pharmacological effect on AA.

Angiotensin I-Converting Enzyme-Inhibitory Activity and Phytochemical Profile of Constituents of the Leaves of Rehmannia glutinosa f. hueichingensis.

The root of Rehmannia glutinosa Liboschitz forma hueichingensis HSIAO has been used as a tonic and treatment for urinary and skin disorders in Japanese Kampo medicine. Phytochemical investigation of the root has been well reported, but that of the leaves is limited. To explore the potential value of R. glutinosa leaves, we focused on the angiotensin I-converting enzyme (ACE)-inhibitory activity. The leaf extract exhibited ACE-inhibitory activity, and the inhibitory potency of leaves was stronger than that of roots. Using this activity as an indicator, we isolated linaride (1), 6-O-hydroxybenzoyl ajugol (2), acteoside (3), leucosceptoside A (4), martynoside (5), luteolin (6), apigenin (7), and chrysoeriol (8) by separating and purifying the extract. We then examined the ACE-inhibitory activities of 1-8, catalpol (9), aucubin (10), ajugol (11), and echinacoside (12). Among them, 3, 6, and 12 displayed the most potent inhibitory activity. A simultaneous analytical method was also developed using compounds contained in R. glutinosa leaves and roots, and their contents were compared. The method consisted of extraction with 50% aqueous methanol under sonication for 60 min and LC/MS measurement. R. glutinosa leaves tended to have higher levels of majority of the analytes than the roots, including 3 and 6, which had higher ACE-inhibitory activity. These results suggest that 3 and 6 contribute to the ACE-inhibitory activity of R. glutinosa leaves, which may represent a useful medicinal resource for hypertension.

Combination of Internal Extractive Electrospray Ionization Mass Spectrometry and Statistical Analysis for High-Throughput Molecular Differentiation of Rehmannia glutinosa Samples.

Rehmannia glutinosa (Gaert.) Libosch. ex Fisch. et Mey. is a perennial herb of the Scrophulariaceae family, which has long enjoyed a good reputation in China, and has a wide range of pharmacological effects and clinical applications. The place of origin is an important factor affecting the chemical composition of R. glutinosa, resulting in different pharmacological effects. Herein, internal extractive electrospray ionization mass spectrometry (iEESI-MS) combined with statistical techniques was established for high-throughput molecular differentiation of different R. glutinosa samples. Dried and processed R. glutinosa samples from four different places of origin were analyzed by iEESI-MS with high throughput (>200 peaks) and rapidness (<2 min/sample) without sample pretreatment. Clear separation models created by OPLS-DA were then established for distinguishing the places of origin of dried and processed R. glutinosa by using the obtained MS data. In addition, the molecular differences between the pharmacological effects of dried and processed R. glutinosa were also investigated by OPLS-DA, and 31 different components were screened out. This work provides a promising method for evaluating the quality of traditional Chinese medicines and studying the biochemical mechanism of processing.

Purification and structural analysis of a novel polysaccharide from Rehmannia Radix Praeparata.

In this paper, the purification, structure, and antioxidant activity of Rehmannia Radix Praeparata polysaccharide (RRPP) were studied. The RRPP was separated using DEAE-52 cellulose and Sephadex G-100. The RRPP consisted of xylose, glucose, rhamnose, galactose, and mannose in ratios of 10.64:5.58:3.52:1.39:1.0. No protein was detected in the RRPP fraction, and the molecular weight of RRPP was about 1.75 × 106 Da. The basic skeleton information was obtained using periodic acid oxidation-Smith degradation, and RRPP contained 1→, 1 → 2, 1 → 3, 1 → 4, 1 → 2,6, 1 → 4,6 or 1 → 6, 1 → 2,3, 1 → 2,3,4, and other glycosidic bonds. Fourier transform infrared spectroscopy also showed that RRPP has both α- and ß-glycosidic bonds. The in vitro antioxidant activity test showed that RRPP could potentialize scavenging effect on ABTS+· and its scavenging rate was 91.3%.

Dried root of Rehmannia glutinosa extracts prevents steroid-induced avascular necrosis of femoral head by activating the wingless-type (Wnt)/ß-catenin signal pathway.

Steroid-induced avascular necrosis of femoral head (SANFH) is one of the most common complications caused by long-term or excessive clinical use of glucocorticoids. This study aimed to investigate the effects of dried root of Rehmannia glutinosa extracts (DRGE) in SANFH. First, SANFH rat model was established by dexamethasone (Dex). Tissue change and proportion of empty lacunae were detected by hematoxylin and eosin staining. Protein levels were detected by western bloting analysis. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) was performed to assess apoptosis of femoral head tissue. Cell viability and apoptosis of MC3T3-E1 cells were assessed by Cell Counting Kit-8 assay and flow cytometry. ALP activity and cell mineralization were detected by ALP staining assay and Alizarin red staining. The findings showed that DRGE improved tissue damage, inhibited apoptosis, and promoted osteogenesis in SANFH rats. In vitro, DRGE increased cell viability, inhibited cell apoptosis, promoted osteoblast differentiation, reduced the levels of p-GSK-3ß/GSK-3ß, but increased the levels of ß-catenin in cells treated with Dex. Furthermore, DKK-1, an inhibitor of the wingless-type (Wnt)/ß-catenin signaling pathway, reversed the effect of DRGE on cell apoptosis and ALP activity in cells treated with Dex. In conclusion, DRGE prevents SANFH by activating the Wnt/ß-catenin signaling pathway, indicating that DRGE may be a hopeful choice drug to prevent and treat patients with SANFH.

[Effect of processing method on chemical constituents of Rehmanniae Radix: based on UHPLC-LTQ-Orbitrap MS].

This study aims to explore the chemical composition of Rehmanniae Radix braised with mild fire and compare the effect of processing method on the chemical composition of Rehmanniae Radix. To be specific, ultra-high performance liquid chromatography with linear ion trap-orbitrap mass spectrometry(UHPLC-LTQ-Orbitrap MS) was used to screen the chemical constituents of Rehmanniae Radix. The chemical constituents were identified based on the relative molecular weight and fragment ions, literature information, and Human Metabolome Database(HMDB). The ion peak area ratio of each component before and after processing was used as the index for the variation. SIMCA was employed to establish principal component analysis(PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA) models of different processed products. According to the PCA plot, OPLS-DA plot, and VIP value, the differential components before and after the processing were screened out. The changes of the content of differential components with the processing method were analyzed. A total of 66 chemical components were identified: 57 of raw Rehmanniae Radix, 55 of steamed Rehmanniae Radix, 55 of wine-stewed Rehmanniae Radix, 51 of repeatedly steamed and sundried Rehmanniae Radix Praeparata, 62 of traditional bran-braised Rehmanniae Radix, and 63 of electric pot-braised Rehmanniae Radix. Among them, the 9 flavonoids of braised Rehmanniae Radix were from Citri Reticulatae Pericarpium. PCA suggested significant differences in the chemical composition of Rehmanniae Radix Praeparata prepared with different processing methods. OPLS-DA screened out 32 chemical components with VIP value >1 as the main differential components. Among the differential components, 9 were unique to braised Rehmanniae Radix(traditional bran-braised, electric pot-braised) and the degradation rate of the rest in braised(traditional bran-braised, electric pot-braised) or repeatedly steamed and sundried Rehmanniae Radix was higher than that in the steamed or wine-stewed products. The results indicated the chemical species and component content of Rehmanniae Radix changed significantly after the processing. The 32 components, such as rehmapicrogenin, martynoside, jionoside D, aeginetic acid, hesperidin, and naringin, were the most important compounds to distinguish different processed products of Rehmanniae Radix. The flavonoids introduced by Citri Reticulatae Pericarpium as excipient may be the important material basis for the effectiveness of braised Rehmanniae Radix compared with other processed products.

Extraction, structure and bioactivities of polysaccharides from Rehmannia glutinosa: A review.

ETHNOPHARMACOLOGIC RELEVANCE: Rehmannia glutinosa (Gaertn.) DC. (RG) is a widely used herb for clearing heat and cooling the blood. Polysaccharides from Rehmannia glutinosa (Gaertn.) DC. (RGPs) have a variety of biological activities, including antioxidation, hypoglycemia, immune enhancement, hematopoiesis promotion, and antianxiety. AIM OF THE STUDY: This review provides up-to-date and comprehensive information on the extraction and separation methods, structural characteristics, and pharmacological activities of RGPs. A more in-depth study on the structure and clinical pharmacology of the RGPs was investigated. To further explore the pharmacological effects of RGPS, and lay a foundation for the safe clinical application and expansion of application scope. MATERIALS AND METHODS: Use Google Scholar, Scifinder, PubMed, Springer, Elsevier, Wiley, Web of Science and other online database search to collect the literature on extraction, separation, structural analysis and pharmacological activity of RGPs published before December 2022. The key words are "extraction", "isolation", "purification" and "pharmacological action" and "Rehmanniae polysaccharide". RESULTS: Rehmannia glutinosa has been widely used in the treatment of diabetes since ancient times, and is known as one of the "Four Sacred Medicines" for the treatment of diabetes, along with Ginseng, Psidium Guajava and Pueraria Mirifica. The active ingredients of Rehmannia glutinosa that have been studied more in the treatment of diabetes are Rehmannia glutinosa polysaccharide and Rehmannia glutinosa oligosaccharide. The content of polysaccharides varies due to different extraction methods, and separation and purification methods. RGPs have a wide range of pharmacological activities, including antitumor, immunomodulatory, neuroprotective effect, hypoglycemic activity, cardioprotective and antioxidant activities. These pharmacological properties lay a foundation for the treatment of tumors, inflammation, hyperglycemia, myocardial ischemia, oxidative stress and other diseases with RGPs. CONCLUSION: Based on its effects of promoting hematopoiesis, antitumor and enhancing immunity, RGPs have been clinically applied in the treatment of chronic aplastic anemia and esophageal cancer, but other effects of RGPs have not been reflected in the clinical practice. In the future, more in-depth research can be conducted on the molecular structure analysis, toxicity, side effects and clinical pharmacological effects of RGPs to further explore the pharmacological effects of RGPs and to lay the foundation for safe clinical application and expansion of application scope.

Structural characterization and anti-inflammatory effects of an arabinan isolated from Rehmannia glutinosa Libosch.

Considering that natural polysaccharides are potential anti-inflammatory agents, in this study, an arabinan (RGP70-2) was isolated and purified from Rehmannia glutinosa Libosch. (R. glutinosa) and its structure was characterized. RGP70-2 was a homogeneous polysaccharide with a molecular weight of 6.7 kDa, with the main backbone comprising →5)-α-L-Araf-(1→, →3)-α-L-Araf-(1→, →2,3,5)-α-L-Araf-(1→, and →2,5)-α-L-Araf-(1 â†’ linkages and the side chain comprising an α-L-Araf-(1 â†’ linkage. In vivo experiments showed that RGP70-2 inhibited ROS production and downregulated the expression of pro-inflammatory cytokines (TNF-α, IL-1ß, and IL-6). In vitro experiments showed that RGP70-2 decreased levels of pro-inflammatory cytokines, inhibited ROS production, and attenuated NF-κB-p65 translocation from the cytoplasm to the nucleus. Our results showed that RGP70-2 may delay inflammation by regulating the ROS-NF-κB pathway. Thus, RGP70-2 has potential applications as an anti-inflammatory agent in the biopharmaceutical industry.

Integrated Metabonomic Study on the Relationship between Medicinal Properties and Efficacy of Rehmanniae Radix.

Each Chinese medicine has its own properties and effects. However, the close connection between the medicinal properties and the effects of the medicine remains unclear. To export the scientific connection between the medicinal properties and efficacy of Rehmanniae Radix (RR), this study established a model and evaluated the therapeutic effects of RR on cold-heat syndrome to access the properties of RR, and then established a blood-heat syndrome model through the injection of rats with dry yeast combined with anhydrous ethanol. Related biochemical indicators (coagulation factors and central pyrogenic factor) were measured to assess the efficacy of RR. Finally, metabonomic technology was used to study the blood-cooling mechanism of RR from two aspects: medicinal properties and efficacy. The comprehensive results suggest that RR can significantly reduce the rectal temperature of blood-heat syndrome model rats and increase both the expression levels of coagulation factors (TNF-[Formula: see text], IL-1[Formula: see text], and IL-6) and the central pyrogenic factors (c-AMP, PGE-2). RR also cools the blood through regulating arginine, proline, phenylalanine, taurine, hypotaurine, sulfur, glycerophospholipid, primary bile acid metabolic pathways, and the tricarboxylic acid cycle. Therefore, RR plays the role of cooling blood by virtue of its cold property. The medicinal property of RR has a guiding effect on the clinical application. Moreover, the integrated metabolomic approach is a powerful tool for studying the properties and efficacy of Chinese medicine.

Effect of processing method on chemical constituents of Rehmanniae Radix: based on UHPLC-LTQ-Orbitrap MS / 中国中药杂志

This study aims to explore the chemical composition of Rehmanniae Radix braised with mild fire and compare the effect of processing method on the chemical composition of Rehmanniae Radix. To be specific, ultra-high performance liquid chromatography with linear ion trap-orbitrap mass spectrometry(UHPLC-LTQ-Orbitrap MS) was used to screen the chemical constituents of Rehmanniae Radix. The chemical constituents were identified based on the relative molecular weight and fragment ions, literature information, and Human Metabolome Database(HMDB). The ion peak area ratio of each component before and after processing was used as the index for the variation. SIMCA was employed to establish principal component analysis(PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA) models of different processed products. According to the PCA plot, OPLS-DA plot, and VIP value, the differential components before and after the processing were screened out. The changes of the content of differential components with the processing method were analyzed. A total of 66 chemical components were identified: 57 of raw Rehmanniae Radix, 55 of steamed Rehmanniae Radix, 55 of wine-stewed Rehmanniae Radix, 51 of repeatedly steamed and sundried Rehmanniae Radix Praeparata, 62 of traditional bran-braised Rehmanniae Radix, and 63 of electric pot-braised Rehmanniae Radix. Among them, the 9 flavonoids of braised Rehmanniae Radix were from Citri Reticulatae Pericarpium. PCA suggested significant differences in the chemical composition of Rehmanniae Radix Praeparata prepared with different processing methods. OPLS-DA screened out 32 chemical components with VIP value >1 as the main differential components. Among the differential components, 9 were unique to braised Rehmanniae Radix(traditional bran-braised, electric pot-braised) and the degradation rate of the rest in braised(traditional bran-braised, electric pot-braised) or repeatedly steamed and sundried Rehmanniae Radix was higher than that in the steamed or wine-stewed products. The results indicated the chemical species and component content of Rehmanniae Radix changed significantly after the processing. The 32 components, such as rehmapicrogenin, martynoside, jionoside D, aeginetic acid, hesperidin, and naringin, were the most important compounds to distinguish different processed products of Rehmanniae Radix. The flavonoids introduced by Citri Reticulatae Pericarpium as excipient may be the important material basis for the effectiveness of braised Rehmanniae Radix compared with other processed products.

Development of Highly Sensitive Method for Sugar Determination in Herbal Medicine; Application of Monosaccharides and Oligosaccharides in Japanese Angelica Root and Rehmannia Root.

We have developed a simple and accurate method for quantifying sugars in herbal medicines, which have hitherto been difficult to quantify. Using ultra performance liquid chromatography-quadrupole-time-of-flight (UPLC-Q-TOF)-MS and two types of columns with different chemical properties, we determined the optimum conditions for separating nine sugars (fructose, galactose, glucose, mannitol, sucrose, melibiose, raffinose, manninotriose, and stachyose) commonly found in herbal medicines. Separation was completed within 10 min when an apHera NH2 HPLC column was used, although galactose and glucose could not be separated. On the other hand, the nine sugars were completely separated within 16 min when a hydrophilic interaction chromatography (HILIC)pak VG-50 2D column was used. The calibration curves obtained using those two columns gave good linearity for the sugar standards, and the coefficient of determination was 0.995 or higher. Both columns showed excellent performance with short analysis time and high sensitivity. Using our developed method, we were able to quantify sugars in galactose-free herbal medicines within 10 min and in herbal medicines containing galactose within 16 min. We revealed that our method could be used for the analysis of sugars in Angelica acutiloba and Rehmannia glutinosa roots.

Ionones and lignans from the fresh roots of Rehmannia glutinosa.

Nine undescribed compounds, together with 21 known components, were isolated from the fresh roots of Rehmannia glutinosa. Their structures were elucidated based on spectroscopic data analysis, and the absolute configurations of undescribed compounds were determined by comparison of their calculated and experimental electronic circular dichroic (ECD) spectra and interpretation of their optical rotation data. The α-glucosidase inhibitory effects of the isolated compounds were investigated and all of them exhibited slightly inhibitory activities.