Antimicrobial Activities of Cinnamon Oil and Cinnamaldehyde from the Chinese Medicinal HerbCinnamomum cassiaBlume

Both Cinnamomum verum J.S. Presl. and Cinnamomum cassia Blume are collectively called Cortex Cinnamonmi for their medicinal cinnamon bark. Cinnamomum verum is more popular elsewhere in the world, whereas C. cassia is a well known traditional Chinese medicine. An analysis of hydro-distilled Chinese cinnamon oil and pure cinnamaldehyde by gas chromatography/mass spectrometry revealed that cinnamaldehyde is the major component comprising 85% in the essential oil and the purity of cinnamaldehyde in use is high (> 98%). Both oil and pure cinnamaldehyde of C. cassia were equally effective in inhibiting the growth of various isolates of bacteria including Gram-positive (1 isolate, Staphylococcus aureus), and Gram-negative (7 isolates, E. coli, Enterobacter aerogenes, Proteus vulgaris, Pseudomonas aeruginosa, Vibrio cholerae, Vibrio parahaemolyticus and Samonella typhymurium), and fungi including yeasts (four species of Candida, C. albicans, C. tropicalis, C. glabrata, and C. krusei), filamentous molds (4 isolates, three Aspergillus spp. and one Fusarium sp.) and dermatophytes (three isolates, Microsporum gypseum, Trichophyton rubrum and T. mentagraphytes). Their minimum inhibition concentrations (MIC) as determined by agar dilution method varied only slightly. The MICs of both oil and cinnamaldehyde for bacteria ranged from 75 μg/ml to 600 μg/ml, for yeasts from 100 μg/ml to 450 μg/ml, for filamentous fungi from 75 μg/ml to 150 μg/ml, and for dermatophytes from 18.8 μg/ml to 37.5 μg/ml. The antimicrobial effectiveness of C. cassia oil and its major constituent is comparable and almost equivalent, which suggests that the broad-spectrum antibiotic activities of C. cassia oil are due to cinnamaldehyde. The relationship between structure and function of the main components of cinnamon oil is also discussed.

Cinnamomum cassia Presl: A Review of Its Traditional Uses, Phytochemistry, Pharmacology and Toxicology

Cinnamomum cassia Presl is a tropical aromatic evergreen tree of the Lauraceae family, commonly used in traditional Chinese medicine. It is also a traditional spice, widely used around the world. This paper summarizes the achievements of modern research on C. cassia, including the traditional uses, phytochemistry, pharmacology and toxicology. In addition, this review also discusses some significant issues and the potential direction of future C. cassia research. More than 160 chemicals have been separated and identified from C. cassia. The main constituents of C. cassia are terpenoids, phenylpropanoids, glycosides, etc. Modern studies have confirmed that C. cassia has a wide range of pharmacological effects, including antitumour, anti-inflammatory and analgesic, anti-diabetic and anti-obesity, antibacterial and antiviral, cardiovascular protective, cytoprotective, neuroprotective, immunoregulatory effects, anti-tyrosinase activity and other effects. However, the modern studies of C. cassia are still not complete and more in-depth investigations need to be conducted in alimentotherapy, health product, toxicity and side effects, and more bioactive components and potential pharmacological effects need to be explored in the future.

Authentication and quantitative analysis on the chemical profile of cassia bark (cortex cinnamomi) by high-pressure liquid chromatography

Cassia bark or cortex cinnamomi, the dried stem bark of Cinnamomum cassia Presl. (Lauraceae), is a popular natural spice and a commonly used herb in traditional Chinese medicine. However, adulterants are frequently found in the market. In this study, 44 samples of Cassia bark including bark from seven related Cinnamomum species were collected from fields and market. Four characteristic components, cinnamaldehyde, cinnamic acid, cinnamyl alcohol, and coumarin were determined by RP-HPLC, and a fingerprint comprised of five markers was established. These results showed that cassia barks contained high contents of cinnamaldehyde (13.01-56.93 mg/g). The highest content of cinnamaldehyde (up to 93.83 mg/g) was found in debarked cortex, which is traditionally regarded as having the best quality in local herb shops. In contrast, the adulterants from the other Cinnamomum species, C. wilsonii Camble, C. japonicum Sieb., C. mairei Levl. and C. burmanii (Nees) Blume, contained low contents of cinnamaldehyde (<2.00 mg/g). The content of cinnamaldehyde in C. loureirii Nees was comparable to that in C. cassia. It is suggested that five characteristic peaks by HPLC are suitable for distinguishing genuine cassia bark from the adulterants and could be applied in the quality control of this commodity.

Inhibitory effect of 2'-hydroxycinnamaldehyde on nitric oxide production through inhibition of NF-kappa B activation in RAW 264.7 cells

Cinnamomum cassia has been widely used for treating dyspepsia, gastritis, and inflammatory disease. In the present study, several of cinnamaldehyde derivatives were synthesized from various cinnamic acid based on the 2'-hydroxycinnamaldehyde isolated from the bark C. cassia Blume was investigated to compare their NO production and NF-kappa B activity from Raw 264.7 cell since nitric oxide (NO) and NF-kappa B have been shown to be implicated factors in the inflammatory disease. The results show that HCA, among the derivatives, most significantly inhibited lipopolysaccharide (LPS)-induced NO production and NF-kappa B transcriptional activity in a dose-dependent manner with an IC(50) value of 8 and 22 microM, respectively. We next investigated putative possible mechanisms of inhibitory effect of HCA on NO production. The inhibition of NO by HCA was consistent with the inhibitory effect on LPS-induced inducible nitric oxide synthase (iNOS) expression. Moreover, HCA inhibited LPS-induced p50 and p65 translocation resulting in the inhibition of the DNA binding activity of the NF-kappa B, a central regulator of iNOS. The present results provided evidence that HCA, among cinnamaledhyde derivatives, has the most inhibitory effect on NO production through inhibition of NF-kappa B activation, and thus can be used as an anti-inflammatory agent.

2-methoxycinnamaldehyde from Cinnamomum cassia reduces rat myocardial ischemia and reperfusion injury in vivo due to HO-1 induction

ETHNOPHARMACOLOGICAL RELEVANCE

Cinnamomum cassia Blume has been used as a traditional Chinese herbal medicine for alleviation of fever, inflammation, chronic bronchitis, and to improve blood circulation.

AIM OF THE STUDY

We addressed whether 2-methoxycinnamaldehyde (2-MCA), one of active ingredients of Cinnamomum cassia, reduces vascular cell adhesion molecule-1 (VCAM-1) expression in tumor necrosis factor-alpha (TNF-α)-activated endothelial cells and protects ischemia/reperfusion (I/R)-injury due to heme oxygenase (HO)-1 induction.

MATERIALS AND METHODS

Adult male rats were subjected to 30 min of ischemia by occlusion of the left anterior descending coronary artery followed by 24h of reperfusion. Rats were randomized to receive vehicle or 2-MCA (i.v.) 10 min before reperfusion.

RESULTS

Administration of 2-MCA significantly improved I/R-induced myocardial dysfunction by increasing the values of the first derivative (±dp/dt) of left ventricular pressure and decreased infarct size. In addition, 2-MCA reduced the expression of high mobility group box 1 (HMGB1), an activator of the inflammatory cascade when released into the extracellular space, and VCAM-1 in I/R myocardium along with increase of HO-1 induction. The reduced injury was accompanied by significantly reduction of neutrophils infiltration and increased SOD activity in ischemic tissues and reduced serum level of cardiac troponin I (cTnI). Furthermore, 2-MCA significantly increased HO-1 induction by translocation of Nrf-2 from cytosol to nucleus in endothelial cells. Inhibition of VCAM-1 expression by 2-MCA was reversed both by SnPPIX, a HO-1 inhibitor and siHO-1 RNA trasfection in TNF-α-activated cells. In addition, 2-MCA significantly inhibited NF-κB luciferase activity in TNF-α-activated endothelial cells. As expected, 2-MCA significantly inhibited monocyte (U937) adhesion to endothelial cells.

CONCLUSION

We concluded that 2-MCA protects of myocardial I/R-injury due to antioxidant and anti-inflammatory action possibly by HO-1 induction which can be explained why Cinnamomum cassia has been used in inflammatory disorders.

Suppression effect of Cinnamomum cassia bark-derived component on nitric oxide synthase

The inhibitory effects of Cinnamomum cassia bark-derived material on nitric oxide (NO) production in RAW 264.7 cells was determined through the evaluation of NO production and expression of inducible nitric oxide and compared to the effects of three commercially available compounds, cinnamyl alcohol, cinnamic acid, and eugenol. The biologically active constituents of C. cassia extract were characterized as trans-cinnamaldehyde by spectral analysis. The inhibitory effects varied with both chemical and concentration used. Potent inhibitory effects of cinnamaldehyde against NO production were 81.5 and 71.7% at 1.0 and 0.5 microg/microL, respectively, and a 41.2% inhibitory effect was revealed at 0.1 microg/microL. However, little or no activity was observed for cinnamic acid and eugenol. Suppression effects of cinnamaldehyde on inducible nitric oxide synthase expression were revealed by Western blot analysis. As a naturally occurring therapeutic agent, trans-cinnamaldehyde could be useful for developing new types of NO inhibitors.

Quantification of flavoring constituents in cinnamon: high variation of coumarin in cassia bark from the German retail market and in authentic samples from indonesia

Coumarin is a flavoring which can cause hepatotoxicity in experimental animals and in a proportion of the human population. The tolerable daily intake (TDI) may be exceeded in consumers with high intake of cinnamon containing high levels of coumarin. The objective of this study was to determine these levels in cinnamon samples and to identify possible factors influencing them. A HPLC method to quantify coumarin and related constituents (cinnamaldehyde, cinnamic acid, cinnamyl alcohol, eugenol) in a single run was used. Results found in 47 cinnamon powder samples obtained from the German retail market confirmed high levels of coumarin in cassia cinnamon. A huge variation was observed in stick samples from two packages (range from below the limit of detection to about 10000 mg/kg). Cassia bark samples of five trees received directly from Indonesia were analyzed additionally. Interestingly, a high variation was observed in one of the trees, whereas no coumarin was detected in the samples of two other trees. In conclusion, coumarin levels in cassia cinnamon can vary widely even within a single tree.

Hypoglycemic activities of A- and B-type procyanidin oligomer-rich extracts from different Cinnamon barks

Procyanidin oligomers in Cinnamon are thought to be responsible for the biological activity in the treatment of diabetes mellitus (DM). To clarify types of procyanidin oligomers in different Cinnamon species and investigate their different effects, the present study investigated procyanidin oligomers in polyphenolic oligomer-rich extracts of three Cinnamon samples by LC-MS methods, and their hypoglycemic activities were detected in vivo and in vitro. The results showed that two of the three samples from Cinnamomum cassia were rich in B-type procyanidin oligomers, and the other sample was rich in A-type procyanidin oligomers. The Cinnamon extracts were administered at doses of 200 and 300 mg/kg body wt. in high-fat diet-fed and low-dose streptozotocin (STZ)-induced diabetic mice for 14 days. The results showed that blood glucose concentrations were significantly decreased in all Cinnamon extract groups compared with the control group (p<0.05). Administration of the Cinnamon extracts significantly increased the consumption of extracellular glucose in insulin-resistant HepG2 cells and normal HepG2 cells compared with the control group. These results suggest that both A- and B-type procyanidin oligomers in different Cinnamon species have hypoglycemic activities and may improve insulin sensitivity in type 2 DM.

Antioxidant activity of various parts of Cinnamomum cassia extracted with different extraction methods

The aim of this study was to investigate the antioxidant activities of various parts (barks, buds, and leaves) of Cinnamomum cassia extracted with ethanol and supercritical fluid extraction (SFE). For the antioxidant activity comparison, IC₅₀ values ofthe SFE and ethanol extracts in the DPPH scavenging assay were 0.562–10.090 mg/mL and 0.072–0.208 mg/mL, and the Trolox equivalent antioxidant capacity (TEAC) values were 6.789–58.335 mmole Trolox/g and 133.039–335.779 mmole Trolox/g, respectively. In addition, the total flavonoid contents were 0.031–1.916 g/ 100 g dry weight of materials (DW) and 2.030–3.348 g/ 100 g DW, and the total phenolic contents were 0.151–2.018 g/ 100 g DW and 6.313–9.534 g/ 100 g DW in the SFE and ethanol extracts, respectively. Based on the results, the ethanol extracts of Cinnamon barks have potential value as an antioxidant substitute and this study also provide a better technique to extract the natural antioxidant substances from C. cassia.

Inhibitory effects of Cinnamomum cassia extract on atopic dermatitis-like skin lesions induced by mite antigen in NC/Nga mice

AIM OF THE STUDY

Cinnamomum cassia (C. cassia) has been traditionally used to treat allergic disease as well as dyspepsia, gastritis, and blood circulation disturbances. However, the antiallergic properties of C. cassia have not been fully verified using scientific tools. This study investigated the effectiveness of C. cassia extract (CCE) as an antiallergic agent in atopic dermatitis model and underlying mechanism.

MATERIALS AND METHODS

The effect of CCE on mite antigen-treated NC/Nga mice was evaluated by examining skin symptom severity, levels of serum IgE, tumor necrosis factor-α (TNF-α), and histamine, skin histology, and mRNA expression of cytokines in the skin lesions. Moreover, the effect of CCE on TNF-α-and interferon-γ (IFN-γ)-induced chemokine production in human keratinocytes was investigated using ELISA.

RESULTS

CCE treatment of NC/Nga mice reduced the dermatitis score and the levels of serum IgE, histamine, and TNF-α. Histological examination showed inhibition of the thickening of the epidermis/dermis and reduced dermal infiltration of inflammatory cells. In skin lesions, mRNA expression of IL-4, TNF-α, and thymus and activation-regulated chemokine (TARC) was inhibited by CCE treatment. The production of TARC, macrophage-derived chemokine, and RANTES from IFN-γ-and TNF-α-stimulated human keratinocytes was suppressed by CCE treatment in a dose-dependent manner.

CONCLUSIONS

CCE inhibits the development of atopic dermatitis-like skin lesions in NC/Nga mice by suppressing the T-helper 2 cell response.

In vitro effect of essential oils from Cinnamomum aromaticum, Citrus limon and Allium sativum on two intestinal flagellates of poultry, Tetratrichomonas gallinarum and Histomonas meleagridis

Essential oils may be effective preventive or curative treatments against several flagelated poultry parasites and may become primordial either to organic farms, or as more drugs are bannished. The anti-flagellate activity of essential oils obtained from fresh leaves of Cinnamomum aromaticum, Citrus limon pericarps and Allium sativum bulbs was investigated in vitro on Tetratrichomonas gallinarum and Histomonas meleagridis. On T. gallinarum, the minimal lethal concentration (MLC) at 24 hours was 0.25 microliter/ml for C. aromaticum oil, and 0.125 microliter/ml for C. limon and A. sativum oils. On H. meleagridis, MLC was 0.5 microliter/ml for C. aromaticum oil and 1 microliter/ml for C. limon and A. sativum oils at 24 and 48 hours. Moreover, no synergistic effects were evidenced in vitro. The essential oil constituents, based on their GC retention times have been also identified. The major component is trans-cinnamaldehyde (79%) for C. aromaticum; limonene for C. limon (71%) and diallyl tri- and disulfide (79%) for A. sativum. Even if concentration and protocol adaptations are required for successful in vivo treatments, it appears that these oils may be useful as chemotherapeutic agents against several poultry parasites.

Quality assessment of Cortex cinnamomi by HPLC chemical fingerprint, principle component analysis and cluster analysis

HPLC fingerprint analysis, principle component analysis (PCA), and cluster analysis were introduced for quality assessment of Cortex cinnamomi (CC). The fingerprint of CC was developed and validated by analyzing 30 samples of CC from different species and geographic locations. Seventeen chromatographic peaks were selected as characteristic peaks and their relative peak areas (RPA) were calculated for quantitative expression of the HPLC fingerprints. The correlation coefficients of similarity in chromatograms were higher than 0.95 for the same species while much lower than 0.6 for different species. Besides, two principal components (PCs) have been extracted by PCA. PC1 separated Cinnamomum cassia from other species, capturing 56.75% of variance while PC2 contributed for their further separation, capturing 19.08% variance. The scores of the samples showed that the samples could be clustered reasonably into different groups corresponding to different species and different regions. The scores and loading plots together revealed different chemical properties of each group clearly. The cluster analysis confirmed the results of PCA analysis. Therefore, HPLC fingerprint in combination with chemometric techniques provide a very flexible and reliable method for quality assessment of traditional Chinese medicines.

Investigation of the Antifungal Activity and Mode of Action of Thymus vulgaris, Citrus limonum, Pelargonium graveolens, Cinnamomum cassia, Ocimum basilicum, and Eugenia caryophyllus Essential Oils

The antimicrobial activity of plant oils and extracts has been recognized for many years. In this study the activity of Thymus vulgaris, Citrus limonum, Pelargonium graveolens, Cinnamomum cassia, Ocimumbasilicum, and Eugenia caryophyllus essential oils (EOs) distributed by Pollena Aroma (Nowy Dwór Mazowiecki, Poland) was investigated against a group of 183 clinical isolates of C. albicans and 76 isolates of C. glabrata. All of the oils exhibited both fungistatic and fungicidal activity toward C. albicans and C. glabrata isolates. The highest activity was observed for cinnamon oil, with MIC (Minimum Inhibitory Concentration) values in the range 0.002⁻0.125% (v/v). The MIC values of the rest of the oils were in the range 0.005% (or less) to 2.5% (v/v). In most cases MFC (Minimum Fungicidal Concentration) values were equal to MIC or twice as high. Additionally, we examined the mode of action of selected EOs. The effect on cell wall components could not be clearly proved. Three of the tested EOs (thyme, lemon, and clove) affected cell membranes. At the same time, thyme, cinnamon, and clove oil influenced potassium ion efflux, which was not seen in the case of lemon oil. All of the tested oils demonstrated the ability to inhibit the transition of yeast to mycelium form, but the effect was the lowest in the case of cinnamon oil.

The essential oil from the twigs of Cinnamomum cassia Presl alleviates pain and inflammation in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Cinnamomum cassia Presl (Lauraceae) can be found southern China and its bark is commonly used for centuries as ingredient in food and cosmetic industry. The twigs of Cinnamomum cassia Presl is popularly used in China to treat inflammatory processes, pain, menstrual disorders, hypertension, fever etc. The aim of this study is to evaluate the antinociceptive and anti-inflammatory properties of the essential oil (EO) from the twigs of Cinnamomum cassia Presl.

MATERIAL AND METHODS

The chemical characterization of the EO was performed by gas chromatography coupled with mass spectrometry (GC-MS). The EO doses of 15, 30, and 60mg/kg were employed in the biological assays. The antinociceptive effects of the EO were evaluated using the models of acetic acid-induced writhing, oxytocin-induced writhing, and formalin and complete Freund's adjuvant (CFA) -induced overt pain tests. we also investigated the effect of the EO in pain intensity to a mechanical stimulus (mechanical hyperalgesia) after carrageenan by using an electronic version of von Frey filaments. Evaluation of anti-inflammatory activity was based on paw edema induced by carrageenan (300µg/25µL/paw) in mice. The levels of cytokines, NO, and PGE2 in paw skin tissue were determined according to instructions. COX-2 and iNOS proteins in paw skin tissue were assessed by Western Blot.

RESULTS

The EO (15, 30, and 60mg/kg) reduced the number of abdominal writhings induced by acetic acid with inhibition of 38.0%, 55.4% and 58.7%, respectively. The EO (15, 30, and 60mg/kg) also reduced the number of abdominal writhings induced by oxytocin with inhibition of 27.3%, 51.7% and 69.0%, respectively. The EO significant inhibited the inflammatory (second phase: 10-30min) phase of the formalin-induced paw flinching and licking at the doses of 15, 30, and 60mg/kg. The EO at the tested doses of 15, 30, and 60mg/kg showed inhibited CFA-induced paw flinching and licking. The EO (15, 30, and 60mg/kg) also inhibited carrageenan-induced mechanical hyperalgesia and paw edema. It also decreased the levels of cytokines (TNF-α, and IL-1β), NO, and PGE2 in carrageenan-induced mice paw skin tissue. Moreover, Western blot analysis showed that COX-2 and iNOS expressions in paw skin tissue of mice were significantly reduced.

CONCLUSIONS

These results demonstrate that the antinociceptive and anti-inflammatory properties of the EO from the twigs of Cinnamomum cassia Presl, corroborating its use in folk medicine.

Potentiation of antifungal activity of amphotericin B by essential oil from Cinnamomum cassia

The antifungal activity of the essential oil from Cinnamomum cassia, alone or combined with amphotericin B, a drug widely used for most indications despite side-effects was investigated. The composition of the oil was analysed by GC/MS and characterized by its very high content of cinnamaldehyde (92.2%). The minimal inhibitory concentration (MIC 80%), used to evaluate the antifungal activity against Candida albicans, was determined by a macrobroth dilution method followed by a modelling of fungal growth. The essential oil of Cinnamomum cassia exhibited strong antifungal effect (MIC 80% = 0.169 microL/mL and K(aff) = 18,544 microL/mL). A decrease of the MIC 80% of amphotericin B was obtained when the culture medium contained essential oil concentrations ranging from 0.08 to 0.1 microL/mL. The strongest decrease (70%) was obtained when the medium contained 0.1 microL/mL of essential oil. This potentiation of amphotericin B obtained in vitro may show promise for the development of less toxic and more effective therapies especially for the treatment of HIV infection.

Cinnamic acid, from the bark of Cinnamomum cassia, regulates glucose transport via activation of GLUT4 on L6 myotubes in a phosphatidylinositol 3-kinase-independent manner

BACKGROUND

Cinnamomum cassia (Family: Lauraceae) is an Ayurvedic medicinal plant used traditionally for the treatment of a number of diseases, including diabetes. The hypoglycemic effect of this plant has been established in vivo. However, the effects of cinnamic acid, isolated from C. cassia, on the insulin signaling cascade in an in vitro model have not been elucidated. Hence, the aim of the present study was to evaluate the anti-diabetic effect of cinnamic acid on glucose transport by L6 myotubes.

METHODS

The mechanism of action of cinnamic acid was determined using specific targets in the insulin signaling pathway, including protein tyrosine phosphatase (PTP) 1B, phosphatidylinositol 3-kinase (PI3-K) and the glucose transporter GLUT4. After differentiation of myoblast to myotubes, the cells were serum deprived for 5 h and then treated with 1 ng/mL cinnamic acid and 50 μmol/L rosiglitazone for 18 h and 100 nmol/L insulin for 20 min for gene expression studies.

RESULTS

Expression of GLUT4 mRNA was increased following treatment of L6 myotubes with 1 ng/mL cinnamic acid. Furthermore, cinnamic acid inhibited PTP1B activity (by 96.5%), but had no significant effect on PI3-K activity.

CONCLUSION

On the basis of the results of the present study, we postulate that cinnamic acid isolated from the hydro-alcoholic extract of Cinnamomum cassia activates glucose transport by a PI3-K-independent pathway. However, the detailed mechanism of action requires further analysis.

Cortex cinnamomi extract prevents streptozotocin- and cytokine-induced β-cell damage by inhibiting NF-κB

AIM: To clarify the mechanism underlying the anti-diabetic activities of cortex cinnamomi extract (CCE).

METHODS: To induce in vivo diabetes, mice were injected with streptozotocin (STZ) via a tail vein (100 mg STZ/kg body weight). To determine the effects of CCE, mice were administered CCE twice daily for 7 d by oral gavage starting 1 wk before the STZ injection. Blood glucose and plasma insulin concentration were measured as an index of diabetes. Also, to induce cytotoxicity of RINm5F cells, we treated with cytokines (IL-1β (2.0 ng/mL) and IFN-γ (100 U/mL)). Cell viability and nitric oxide production were measured colorimetrically. Inducible nitric oxide synthase (iNOS) mRNA and protein expression were determined by RT-PCR and Western blotting, respectively. The activation of NF-κB was assayed by using gel mobility shift assays of nuclear extracts.

RESULTS: Treatment of mice with STZ resulted in hyperglycemia and hypoinsulinemia, which was further evidenced by immunohistochemical staining of islets. However, the diabetogenic effects of STZ were completely prevented when mice were pretreated with CCE. The inhibitory effect of CCE on STZ-induced hyperglycemia was mediated through the suppression of iNOS expression. In rat insulinoma RINm5F cells, CCE completely protected against interleukin-1β and interferon-γ-mediated cytotoxicity. Moreover, RINm5F cells incubated with CCE showed significant reductions in interleukin-1β and interferon-γ-induced nitric oxide production and in iNOS mRNA and protein expression, and these findings correlated well with in vivo observations.

CONCLUSION: The molecular mechanism by which CCE inhibits iNOS gene expression appears to involve the inhibition of NF-κB activation. These results reveal the possible therapeutic value of CCE for the prevention of diabetes mellitus progression.

The anti-diabetic effects and pharmacokinetic profiles of berberine in mice treated with Jiao-Tai-Wan and its compatibility

Jiao-Tai-Wan (JTW), a classical Chinese prescription, has been clinically employed to treat diabetes mellitus in recent years. To investigate the comparative evaluations on anti-diabetic effects and pharmacokinetics of the active ingredient berberine in mice treated with JTW in various combinations of its constituent herbs. In our study, the anti-diabetic study was carried out in diabetic mice induced by intraperitoneal injection of streptozotocin. The diabetic mice were randomly assigned to three therapy groups and orally administered with different prescription proportions of Rhizoma Coptidis and Cinnamomum cassia respectively. The level of plasma glucose, lipid profile and parameters related to oxidative stress were determined. The concentrations of berberine in non-diabetic mice plasma were determined using HPLC, and main pharmacokinetic parameters were investigated. The results indicated that the compatibility effects of ingredients present in Cinnamomum cassia could affect the anti-diabetic ability and pharmacokinetics of berberine in JTW.

Phenolic Constituents Isolated from the Twigs of Cinnamomum cassia and Their Potential Neuroprotective Effects

Seven new α,β-diphenyl-γ-butyrolactones (1-7), three new lignans (8-10), five new neolignans (11-15), two new 1,3-biphenylpropanoids (16 and 17), and a new flavonol galactoside-lignan ester (18), together with 43 known compounds (19-61), were isolated from the twigs of Cinnamomum cassia. Their structures were elucidated by spectroscopic data analysis as well as chemical methods. The α,β-diphenyl-γ-butyrolactones are a class of unique natural compounds that have only been isolated from C. cassia. Compounds 11 and 12 are rare examples of neolignans possessing a 1,2-dioxetane moiety. Compound 13 is a new oxyneolignan possessing a unique C-9-O-C-9' linkage between the benzopyran and cinnamyl alcohol moieties. Compound 15 is the first example of a natural neolignan possessing a 2-styryl-3-phenyltetrahydrofuran skeleton. The isolated compounds were evaluated for their neuroprotective activities against tunicamycin-induced cytotoxicity in SH-SY5Y cells. Compounds 3, 5, 10, 11, 12, 20, 36, and 56 showed statistically significant neuroprotective activity with EC₅₀ values ranging between 21 and 75 μM.

Antioxidative effects of Cinnamomi cassiae and Rhodiola rosea extracts in liver of diabetic mice

Both Cinnamomi cassiae and Rhodiola rosea extracts are used as anti-diabetic folk medicines. Recently, increased oxidative stress was shown to play an important role in the etiology and pathogenesis of diabetes mellitus and its complications. This study was designed to examine the effects of Cinnamomi cassiae and Rhodiola rosea extracts on blood glucose, lipid peroxidation, the level of reduced glutathione and its related enzymes (glutathione reductase, glutathione S-transferase), and the activity of the antioxidant enzymes (catalase, superoxide dismutase and glutathione peroxidase) in the liver of db/db mice. Diabetic C57BL/Ks db/db mice were used as experimental models. Mice were divided into control (n=10), Cinnamomi cassiae (200 mg/kg/day, n=10), and Rhodiola rosea (200 mg/kg/day, n=10) treated groups for 12 weeks of treatment. These type II diabetic mice were used to investigate the effects of Cinnamomi cassiae and Rhodiola rosea on blood glucose, reduced glutathione, glutathione reductase, glutathione S-transferase, glutathione peroxidase, lipid peroxidation, catalase and superoxide dismutase. Cinnamomi cassiae and Rhodiola rosea extracts significantly decreased on blood glucose, increased levels of reduced glutathione and the activities of glutathione reductase, glutathione S-transferase, glutathione peroxidase, catalase and superoxide dismutase in the liver. Extract treatment also significantly decreased lipid peroxidation. Cinnamomi cassiae and Rhodiola rosea extracts may be effective for correcting hyperglycemia and preventing diabetic complications.

Bioactive A-type proanthocyanidins from Cinnamomum cassia

Two trimeric proanthocyanidins, cinnamtannin B-1 (1) and cinnamtannin D-1 (2), have been isolated from the bark of Cinnamomum cassia along with the known tetramer parameritannin A-1 (3) and a previously unreported tetramer, named cassiatannin A (4). The structures of 1-4 were elucidated on the basis of 1D and 2D NMR, MS, and CD analyses and compared to the reported data. Proanthocyanidins (1-4) possess significant in vitro inhibitory activity against cyclooxygenase-2 (COX-2) at micromolar concentrations.

Identification of compounds from the water soluble extract of Cinnamomum cassia barks and their inhibitory effects against high-glucose-induced mesangial cells

The difficulty of diabetic nephropathy (DN) treatment makes prevention the best choice. Cinnamomum cassia barks, known as Chinese cinnamon or Chinese cassia, is one of the most popular natural spices and flavoring agents in many parts of the World. Since previous reports indicated that Chinese cinnamon extract could be used for the treatment of diabetes, we proposed that this spice may be beneficial for the prevention of DN. However, the responsible compounds need to be further identified. In this study, we isolated three new phenolic glycosides, cinnacassosides A–C (1-3), together with fifteen known compounds from the water soluble extract of Chinese cinnamon. The structures of the new compounds were identified by comprehensive spectroscopic evidence. Eleven compounds (6-9, 11, 13-18) were isolated from this spice for the first time, despite extensive research on this species in the past, which added new facets for the chemical profiling of this spice. These isolates were purposely evaluated for their inhibitory effects on IL-6 and extracellular matrix production in mesangial cells which are definitely implicated in DN. The results showed that compounds 4-8 could inhibit over secretion of IL-6, collagen IV and fibronectin against high-glucose-induced mesangial cells at 10 µM, suggesting that Chinese cinnamon could be used as a functional food against DN.

Comparative pharmacokinetic behavior of glycyrrhetic acid after oral administration of glycyrrhizic acid and Gancao-Fuzi-Tang

Comparative pharmacokinetic profiles of glycyrrhetic acid (GA), glycyrrhizic acid (GL) and Gancao-Fuzi-Tang (KF) after oral administration of GL and KF were studied. Plasma samples taken from rats were acidified with acetic acid and GA was extracted with isopropanol-ethyl ether (1 : 1). Separation of GA was performed on a C(18) column with the detection wavelength set at 254 nm. The mobile phase was methanol-acetonitrile-water-acetic acid (58 : 18 : 24 : 1 v/v). The results showed that the mean residence time and area under the curve of GA in KF-administered rats were 27.6+/-1.5 h and 122.8+/-46.7 microg.h/ml respectively, which were significantly different from those in GL-administered rats (15.0+/-2.0 h and 40.9+/-9.6 microg.h/ml, respectively). The results suggest the increased effect of GA after oral administration of KF in comparison with GL.

Preparation, characterization, and biological activity of Cinnamomum cassia essential oil nano-emulsion

To solve the problems of low bioavailability and unstable properties of Cinnamomum cassia Essential oil (CCEO), encapsulation technology was introduced as an effective means to improve its shortcomings. In this study, Cinnamomum cassia Essential oil nano-emulsion (CCEO-NE) was successfully synthesized by the oil-in-water method and characterized by standard analytical methods, including dynamic light scattering (DLS), Scanning electron microscopy (SEM), and Transmission electron microscopy (TEM). The results show that the synthesized CCEO is spherical, smooth in surface, and uniform in shape, with an average particle size of 221.8 ± 1.95 nm, which is amorphous. In this experiment, by simulating the digestion of CCEO-NE in the gastrointestinal tract, it was found that CCEO-NE was undigested in the oral cavity, mainly in the stomach, followed by the small intestine. By understanding the digestion of CCEO-NE, we can improve the potential of CCEO bioavailability in food and drug applications. In addition, through the study of ABTS and DPPH free radicals by CCEO and CCEO-NE, it was found that the antioxidant activity of CCEO-NE was more potent than that of CCEO. When the concentration of CCEO-NE and CCEO is 400 μg/mL, the DPPH free radical scavenging rate is 92.03 ± 0.548% and 80.46 ± 5.811%, respectively. In comparison, ABTS free radical scavenging rate is 90.35 ± 0.480% and 98.44 ± 0.170% when the concentration of CCEO- NE, and CCEO is 75 μg/mL, respectively. The antibacterial test shows that CCEO-NE can inhibit both Gram-positive and Gram-negative bacteria. Among them, CCEO-NE has a stronger antibacterial ability than CCEO, and the maximum inhibition zone diameter of CCEO can reach 15 mm, while that of CCEO-NE can reach 18 mm. Meanwhile, SEM and TEM showed that CCEO-NE treatment destroyed the ultrastructure of bacteria. Generally speaking, we know the situation of CCEO in the gastrointestinal tract. CCEO-NE has more potent antioxidant and antibacterial ability than CCEO. Our research results show that whey protein is an effective packaging strategy that can improve the effectiveness, stability, and even bioavailability of CCEO in various applications, including food and health care industries.

Anti-diabetic nephropathy compounds from Cinnamomum cassia

ETHNOPHARMACOLOGICAL RELEVANCE

The bark of Cinnamomum cassia, called 'Rou-Gui', a traditional spice and medicine in China, is used to treat diseases resulted from kidney yang deficiency, including diabetic nephropathy. The aim of this study is to investigate the anti-diabetic nephropathy activity of Rou-Gui and the active compounds in it.

MATERIALS AND METHODS

The air-dried bark of C. cassia was extracted with 90% EtOH, the obtained residue was successively partitioned by petroleum ether, EtOAc, and n-BuOH followed by concentrating to give petroleum ether (RG-1), EtOAc (RG-2), n-BuOH (RG-3), and water fraction (RG-4), respectively. The anti-diabetic nephropathy activity of fraction (RG-1-4) was evaluated in vitro by inhibiting the expression of fibronectin, monocyte chemoattractant protein-1 and interleukin-6 in high-glucose-induced mesangial cells. By bioassay screenings, repeated column chromatography on fractions of RG-1, 2, and 3, led to the isolation of 23 compounds, whose structures were determined by extensive spectroscopic analyses, and the anti-diabetic nephropathy activity of the isolated compounds was also evaluated.

RESULTS

Four new sesquiterpenoids, cinnamoids A-D (1-4), a new natural product (5), and 18 known compounds (6-23) were isolated from the EtOH extract of the bark of C. cassia under the bioassay-guided screenings. The anti-diabetic nephropathy activity assay showed that fractions of RG-1, 2, and 3 could significantly inhibit the production of fibronectin, monocyte chemoattractant protein-1 and interleukin-6 in high-glucose-stimulated mesangial cells at the concentration of 50 μg/ml; and sesquiterpenoids 5, 6, 14 and compound 20 could significantly inhibit the expression of fibronectin, monocyte chemoattractant protein-1 and interleukin-6 at the concentration of 50 μM.

CONCLUSIONS

The results revealed that sesquiterpenoids may be the active compounds in C. cassia bark on diabetic nephropathy which provided new evidences for the traditional use of this herb to treat diabetic nephropathy and associated kidney diseases.