Ramulus Cinnamomi essential oil exerts an anti-inflammatory effect on RAW264.7 cells through N-acylethanolamine acid amidase inhibition.

ETHNOPHARMACOLOGICAL RELEVANCE: Ramulus Cinnamomi, the dried twig of Cinnamomum cassia (L.) J.Presl., is a traditional Chinese medicine (TCM) with anti-inflammatory effects. The medicinal functions of Ramulus Cinnamomi essential oil (RCEO) have been confirmed, although the potential mechanisms by which RCEO exerts its anti-inflammatory effects have not been fully elucidated. AIM OF THE STUDY: To investigate whether N-acylethanolamine acid amidase (NAAA) mediates the anti-inflammatory effects of RCEO. MATERIALS AND METHODS: RCEO was extracted by steam distillation of Ramulus Cinnamomi, and NAAA activity was detected using HEK293 cells overexpressing NAAA. N-Palmitoylethanolamide (PEA) and N-oleoylethanolamide (OEA), both of which are NAAA endogenous substrates, were detected by liquid chromatography with tandem mass spectrometry (HPLC-MS/MS). The anti-inflammatory effects of RCEO were analyzed in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, and the cell viability was measured with a Cell Counting Kit-8 (CCK-8) kit. The nitric oxide (NO) in the cell supernatant was measured using the Griess method. The level of tumor necrosis factor-α (TNF-α) in the RAW264.7 cell supernatant was determined using an enzyme-linked immunosorbent assay (ELISA) kit. The chemical composition of RCEO was assessed by gas chromatography-mass spectroscopy (GC-MS). The molecular docking study for (E)-cinnamaldehyde and NAAA was performed by using Discovery Studio 2019 software (DS2019). RESULTS: We established a cell model for evaluating NAAA activity, and we found that RCEO inhibited the NAAA activity with an IC50 of 5.64 ± 0.62 µg/mL. RCEO significantly elevated PEA and OEA levels in NAAA-overexpressing HEK293 cells, suggesting that RCEO might prevent the degradation of cellular PEA and OEA by inhibiting the NAAA activity in NAAA-overexpressing HEK293 cells. In addition, RCEO also decreased NO and TNF-α cytokines in lipopolysaccharide (LPS)-stimulated macrophages. Interestingly, the GC-MS assay revealed that more than 93 components were identified in RCEO, of which (E)-cinnamaldehyde accounted for 64.88%. Further experiments showed that (E)-cinnamaldehyde and O-methoxycinnamaldehyde inhibited NAAA activity with an IC50 of 3.21 ± 0.03 and 9.62 ± 0.30 µg/mL, respectively, which may represent key components of RCEO that inhibit NAAA activity. Meanwhile, docking assays revealed that (E)-cinnamaldehyde occupies the catalytic cavity of NAAA and engages in a hydrogen bond interaction with the TRP181 and hydrophobic-related interactions with LEU152 of human NAAA. CONCLUSIONS: RCEO showed anti-inflammatory effects by inhibiting NAAA activity and elevating cellular PEA and OEA levels in NAAA-overexpressing HEK293 cells. (E)-cinnamaldehyde and O-methoxycinnamaldehyde, two components in RCEO, were identified as the main contributors of the anti-inflammatory effects of RCEO by modulating cellular PEA levels through NAAA inhibition.

Real-time process quality control of ramulus cinnamomi by critical quality attribute using microscale thermophoresis and on-line NIR.

Real-time process quality control of ramulus cinnamomi (cassia twig) is still a challenge in pharmaceutical industry. Rapid critical quality attribute (CQA) determination of ramulus cinnamomi is essential for quality control. Microscale thermophoresis (MST) was used to investigate the CQA of ramulus cinnamomi by the interaction with biomacromolecule. There was a good affinity between cinnamaldehyde and human serum albumin (HSA) with Ka as 2.1722×103mol/L. It was an excellent combination of similarity to ibuprofen with same binding force as discovered as hydrogen bond and van der Waals force. Furthermore, regarding cinnamaldehyde as CQA, on-line near-infrared was used to monitor pilot extraction process of ramulus cinnamomi combined with high performance liquid chromatography (HPLC). Quantitative model was established with Rpre2 as 0.9798 and RMSECV as 0.0993, suggesting the NIR model was so robust and accurate for pilot process quality control. This method provided a perfect guideline for rapid CQA determination and real-time process quality control of Chinese materia medica (CMM) based on a vital CQA.

Protective effect of gui zhi (Ramulus Cinnamomi) on abnormal levels of four amino acid neurotransmitters by chronically ma huang (Herb Ephedra) intoxicated prefrontal cortex in rats treated with a ma huang-gui zhi herb pair.

ETHNOPHARMACOLOGICAL RELEVANCE: The Herb Ephedra (Ma Huang in Chinese)-Ramulus Cinnamomi (Gui Zhi in Chinese) herb pair is a classic traditional Chinese herb pair used to treat asthma, nose and lung congestion, and fever with anhidrosis. In previous study, we found that chronic administration of ma huang induced obvious neurodegeneration in rat brains, with the prefrontal cortex showing the greatest effect. Gui zhi decreased hyperactivity produced by repeated ma huang administration, and attenuated oxidative stress in rat prefrontal cortex induced by ma huang. AIM OF THE STUDY: The study was aimed to investigate the protective effect of gui zhi on ma huang-induced abnormal levels of four amino acid neurotransmitters in rat prefrontal cortex. MATERIALS AND METHODS: All ma huang and ma huang-gui zhi herb pair extracts were prepared using methods of traditional Chinese medicine and were normalized based on the ephedrine content. Two-month-old male Sprague-Dawley rats (6 rats/group) were administered ma huang or ma huang-gui zhi herb pair extracts for 1, 3, 5 or 7 days (ephedrine = 48 mg/kg). The contents of ephedrine, glutamate (Glu), aspartic acid (Asp), glycine (Gly), and gamma-aminobutyric acid (GABA) in the prefrontal cortex were determined using ultra-high-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) at 0.5, 1.0, 5.0 h after administration. RESULTS: Ma huang significantly enhanced the levels of GABA, Gly, Glu and Asp in the prefrontal cortex, while gui zhi partially abolished the effects. CONCLUSIONS: Ma huang-induced neurotoxicity may be associated with its effects on amino acid neurotransmitters. Gui zhi is a promising neuroprotective agent against for ma huang-induced neurotoxicity. The information presented in this study will help supplement the available data for future ma huang-gui zhi herb pair compatibility studies.

Antipyretic Effect of Herba Ephedrae-Ramulus Cinnamomi Herb Pair on Yeast-Induced Pyrexia Rats: A Metabolomics Study.

OBJECTIVE: To investigate the antipyretic mechanism of Herba Ephedrae (Eph)-Ramulus Cinnamomi (RC) herb pair on yeast-induced pyrexia in rats. METHODS: Totally 30 qualified male SD rats were randomly assigned to the normal control (NC) group, the pyrexia model (model) group, the Eph, RC and Eph-RC treatment groups by a random digital table, 6 rats in each group. Each rat received a 20% aqueous suspension of yeast (10 mL/kg) except the NC group. The 3 treatment groups were administered 8.1, 5.4 and 13.5 g/kg Eph, RC and Eph-RC respectively at 5 and 12 h after yeast injection, the NC group and the model groups were administered equal volume of distilled water. Rectal temperatures were measured at 0, 6, 8, 10, 12, 15, 18, 24 and 30 h and urine was collected prior to yeast injection and at 6, 10, 18, 24, 30, and 36 h after yeast injection. Then urine metabolomic profiling by gas chromatography tandem mass spectrometry, coupled with multivariate statistical analysis and pattern recognition techniques were used to explore the antipyretic effects of Eph-RC. Partial least squares discriminate analysis was used to analyze the metabolomics dataset including classification and regression in metabolomics plot profiling. RESULTS: Compared with the NC group, rectal temperatures were significantly higher in the model group (P<0.01), while 3 treatment groups decreased significantly compared with the model group (P<0.05 or P<0.01). Rectal temperatures of Eph-RC-treated rats started to go down at 6 h, and markedly decreased at 8, 12, 15, 18 and 24 h (P<0.05 or P<0.01), while those of the Eph and RC groups had decreased firstly at 8 h and were markedly lower at 12 h (P<0.05 or P<0.01). Seventeen potential biomarkers related to pyrexia were confirmed and identified, including pyruvic acid, L-phenylalanine, L-tyrosine, phenylacetic acid, hippuric acid, succinic acid, citrate and so on. Eight potential alterations of metabolic pathways including phenylalanine metabolism, citrate cycle, tryptophan metabolism, biosynthesis of valine, leucine and isoleucine, were identified in relation to the antipyretic effects of Eph-RC using MetPA software. CONCLUSION: The antipyretic effect of Eph-RC herb pair on yeast-induced pyrexia in rats involved correction of perturbed amino acid, fatty acid, and carbohydrate metabolism according to the metabolic pathway analysis with MetPA.

Ramulus Cinnamomi extract attenuates neuroinflammatory responses via downregulating TLR4/MyD88 signaling pathway in BV2 cells.

Ramulus Cinnamomi (RC), a traditional Chinese herb, has been used to attenuate inflammatory responses. The purpose of this study was to investigate the effect of RC extract on lipopolysaccharide (LPS)-induced neuroinflammation in BV2 microglial cells and the underlying mechanisms involved. BV2 cells were incubated with normal medium (control group), LPS, LPS plus 30 µg/mL RC extract, or LPS plus 100 µg/mL RC extract. The BV2 cell morphology was observed under an optical microscope and cell viability was detected by MTT assay. Nitric oxide level in BV2 cells was detected using Griess regents, and the levels of interleukin-6, interleukin-1ß, and tumor necrosis factor α in BV2 cells were determined by ELISA. The expression levels of cyclooxygenase-2, Toll-like receptor 4 and myeloid differentiation factor 88 proteins were detected by western blot assay. Compared with the LPS group, both 30 and 100 µg/mL RC extract had no significant effect on the viability of BV2 cells. The levels of nitric oxide, interleukin-6, interleukin-1ß and tumor necrosis factor α in BV2 cells were all significantly increased after LPS induction, and the levels were significantly reversed after treatment with 30 and 100 µg/mL RC extract. Furthermore, RC extract significantly inhibited the protein expression levels of cyclooxygenase-2, Toll-like receptor 4 and myeloid differentiation factor 88 in LPS-induced BV2 cells. Our findings suggest that RC extract alleviates neuroinflammation by downregulating the TLR4/MyD88 signaling pathway.

Antifungal Activity of Ramulus cinnamomi Explored by ¹H-NMR Based Metabolomics Approach.

A ¹H nuclear magnetic resonance (NMR)-based approach to metabolomics combined bioassay was used to elucidate the antifungal activity of cinnamaldehyde (the main active compound of Ramulus cinnamomi) isolated from Ramulus cinnamomi (RC). Orthogonal signal correction partial least-squares discriminant analysis (OSC-PLS-DA) of NMR data was constructed to analyze all the P. italicum data acquired from the control and treatment groups at 4, 8, and 12 h. Metabolic profiles disclosed metabolic changes that were related to the antifungal effects of cinnamaldehyde against P. italicum including oxidative stress, disorder of energy metabolism, amino acids, and nucleic acids metabolism in treatment group. This integrated metabolomics approach provided an effective way to detect the antifungal effects of cinnamaldehyde against P. italicum dynamically.

Effect of Rhizoma Polygoni Cuspidati and Ramulus Cinnamomi compatibility on uric acid metabolism and urinary neutrophil gelatinase-associated lipocalin and kidney injury molecule-1 in rats with hyperuricemia.

OBJECTIVE: To explore the effects of Rhizoma Polygoni Cuspidati and Ramulus Cinnamomi compatibility (PR) on uric acid metabolism and the expression of urinary neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) in rats with hyperuricemia. METHODS: Seventy male Sprague Dawley (SD) rats were randomly divided into 7 groups with 10 rats per group, including the normal group, model group, allopurinol group, benzbromarone group and PR groups at 3 doses (3.5, 7, 14 g/kg). Except the normal group, rats of the other groups were intragastrically administered 100 mg/kg hypoxanthine and 250 mg/kg ethambutol, and subcutaneously injected with 200 mg/kg potassium oxonate. All rats were continuously modeled for 17 days, and gavaged with corresponding drugs. The rats of the normal and model groups were gavaged with saline, once a day, for 2 weeks. The levels of serum uric acid (SUA), blood urea nitrogen (BUN) and creatinine (Cr) were determined. In addition, the contents of NGAL and KIM-1 in urine and the mRNA and protein expressions of xanthine oxidase (XOD) in liver of hyperuricemia rats were measured by reverse transcription polymerase chain reaction (RT-PCR) and Western blot, respectively. Moreover, the pathological changes of kidney were analyzed by hematoxylin and eosin (HE) stain method. RESULTS: Compared with the normal group, the levels of SUA, BUN, NGAL and KIM-1 and the expressions of hepatic XOD mRNA and protein in the hyperuricemia rats were increased signifificantly (P<0.01). PR signifificantly decreased the levels of SUA, BUN, NGAL and KIM-1 and down-regulated the mRNA and protein expressions of hepatic XOD (P<0.05 or P<0.01). In addition, the pathological changes of kidney were signifificantly suppressed by oral administration of PR. CONCLUSIONS: PR ameliorated uric acid metabolism and protected renal function, the underlying mechanism was mediated by decreasing the levels of SUA, BUN, NGAL and KIM-1, inhibiting the expression of hepatic XOD and ameliorating the pathological change of kidney.

Analysis of bioactive components and pharmacokinetic study of herb-herb interactions in the traditional Chinese patent medicine Tongmai Yangxin Pill.

Tongmai Yangxin (TMYX) Pill is a traditional Chinese patent medicine, composed of eleven Chinese medicinal herbs. It has been used to treat coronary heart disease for several decades. In this study, six male Sprague-Dawley rats were dosed orally with TMYX methanol extract, and a serum pharmacochemistry technique was used to screen absorbed bioactive compounds by UPLC/Q-TOF-MS. By comparing MS spectra to the published literature data, 40 bioactive components were identified. The results indicated that almost 45% of the absorbed compounds were from Radix Glycyrrhizae (GC). Subsequently, a reliable HPLC method was used to determine the concentrations of liquiritin, liquiritigenin, isoliquiritigenin, glycyrrhizic acid, and glycyrrhetinic acid in rat plasma following oral administration of GC or the combination of GC and Ramulus Cinnamomi (GZ). The results showed that GZ enhanced the absorption of four bioactive components: liquiritigenin, isoliquiritigenin, glycyrrhizic acid, and glycyrrhetinic acid. The data demonstrate that herb combination in TMYX Pill exhibit a synergistic action.

The comparative pharmacokinetics of four bioactive ingredients after administration of Ramulus Cinnamomi-Radix Glycyrrhizae herb pair extract, Ramulus Cinnamomi extract and Radix Glycyrrhizae extract.

Ramulus Cinnamomi (RC)-Radix Glycyrrhizae (RG) is a classic herb pair, which is commonly used as a fixed form to treat cardiovascular disease in the clinic. Our work aimed to compare the pharmacokinetic difference of cinnamic acid, liquiritin, isoliquiritigenin and glycyrrhetinic acid in rats after oral administration of the RC-RG herb pair extracts [Guizhigancao Decoction (GGD) and Lingguizhugan Decoction (LGZGD)] and the single RC or RG extract. A HPLC-MS method was developed and validated to study comparative pharmacokinetics. The pharmacokinetic parameters (Cmax , AUC, MRT) of four compounds between the RC-RG herb pair group and the single herb (RC or RG) group showed significant differences (p < 0.05). Compared with the single herb (RC or RG) group, higher peak concentration, slower elimination and larger exposure could be observed after giving the RC-RG herb-pair extracts. The pharmacokinetic differences might indicate the relativity of remedy in the RC-RG herb pair and provide scientific information for rational administration of the drug in the clinic. Copyright © 2016 John Wiley & Sons, Ltd.