Study on Oleum cinnamomi Inhibiting Cutibacterium acnes and Its Covalent Inhibition Mechanism.

Oleum cinnamomi (OCM) is a volatile component of the Cinnamomum cassia Presl in the Lauraceae family, which displays broad-spectrum antibacterial properties. It has been found that OCM has a significant inhibitory effect against Cutibacterium acnes (C. acnes), but the precise target and molecular mechanism are still not fully understood. In this study, the antibacterial activity of OCM against C. acnes and its potential effect on cell membranes were elucidated. Metabolomics methods were used to reveal metabolic pathways, and proteomics was used to explore the targets of OCM inhibiting C. acnes. The yield of the OCM was 3.3% (w/w). A total of 19 compounds were identified, representing 96.213% of the total OCM composition, with the major constituents being phenylpropanoids (36.84%), sesquiterpenoids (26.32%), and monoterpenoids (15.79%). The main component identified was trans-cinnamaldehyde (85.308%). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of OCM on C. acnes were 60 µg/mL and 180 µg/mL, respectively. The modified proteomics results indicate that cinnamaldehyde was the main bioactive ingredient within OCM, which covalently modifies the ABC transporter adenosine triphosphate (ATP)-binding protein and nicotinamide adenine dinucleotide (NADH)-quinone oxidoreductase, hindering the amino acid transport process, and disrupting the balance between NADH and nicotinamide adenine dinucleoside phosphorus (NAD+), thereby hindering energy metabolism. We have reported for the first time that OCM exerts an antibacterial effect by covalent binding of cinnamaldehyde to target proteins, providing potential and interesting targets to explore new control strategies for gram-positive anaerobic bacteria.

Quality Control of Oleum Cinnamomi Assisted by Network Pharmacology Strategy.

Oleum Cinnamomi is a traditional medicine used by the Hmong, the essential oil obtained from Fructus Cinnamomi, for the treatment of coronary heart disease. Information regarding the efficient quality control markers of it is lacking, which has become a bottleneck restricting its development and utilization. Here, an integrated qualitative analysis approach based on a GC-MS and network pharmacology strategy was applied to explore quality control markers for the assessment of Oleum Cinnamomi. Firstly, the compounds of Oleum Cinnamomi were detected by GC-MS. In total, 57 chemical components were identified, mainly monoterpenes and sesquiterpenes, accounting for 83.05% of total essential oil components. Secondly, network pharmacology was adopted to explore the compounds linked to target genes of coronary heart disease. Fifty-two compounds were found, indicating the effectiveness of Oleum Cinnamomi in the treatment of coronary heart disease. Among them, 10 compounds, including eucalyptol, were chosen as potential effective compounds in Oleum Cinnamomi. Thirdly, an established GC-MS SIM method was validated and applied for the simultaneous determination of the contents of these 10 compounds using 20 sample batches of Oleum Cinnamomi. It was preliminarily found that the contents of these 10 compounds differed in Oleum Cinnamomi from different origins. Finally, quantitative analyte data were analyzed using multivariate statistical analysis to determine Oleum Cinnamomi quality. Four compounds (eucalyptol, p-cymene, sabinene, ß-pinene) were identified as chemical markers for quality control. Accordingly, this study provides new strategies to explore the quality control markers and develops a novel method for the quality assessment of Oleum Cinnamomi.

Dietary Supplementation with Oleum Cinnamomi Improves Intestinal Functions in Piglets.

The present study was to determine the efficacy of dietary supplementation with oleum cinnamomi (OCM) on growth performance and intestinal functions in piglets. Sixteen piglets (24-day-old) were randomly assigned to the control or OCM groups. Piglets in the control group were fed a basal diet, whereas piglets in the OCM group were fed the basal diet supplemented with 50 mg/kg OCM. On day 20 of the trial, blood samples and intestinal tissues were obtained from piglets. Compared with the control group, dietary OCM supplementation increased (p < 0.05) average daily feed intake, plasma insulin levels, villus width and villous surface area in the duodenum and jejunum, DNA levels and RNA/DNA ratios in the ileum, the abundance of Enterococcus genus and Lactobacillus genus in caecum digesta, mRNA levels for epithelial growth factor receptor (EGFR), Ras, extracellular signal-regulated kinase 1/2 (Erk1/2), b-cell lymphoma-extra large (Bcl-xL), villin, junctional adhesion molecule A (JAM-A), myxovirus resistance (MX) 1, MX2 and regenerating islet-derived protein 3 gamma (REG3G), and protein abundances of Ras and claudin-1, but decreased (p < 0.05) diarrhoea incidence; the abundances of Enterobacteriaceae family, Enterococcus genus, Lactobacillus genus, Bifidobacterium genus, and Clostrium coccoides in the colon digesta, and AMP-activated protein kinase (AMPK) mRNA levels and caspase-3 protein abundance in the jejunal mucosa of piglets. Taken together, these data indicate that dietary OCM supplementation modulates intestinal microbiota and improves intestinal function in weanling pigs. OCM is an effective feed additive and alternative to feed antibiotics for improving intestinal health in swine.

Quantification of six volatile oil constituents of Oleum Cinnamomi in rat plasma and multiple tissues using GC-MS and its application to pharmacokinetic and tissue distribution studies.

Oleum Cinnamomi is the essential oil obtained from the herb Fructus Cinnamomi which is used by the Hmong people in traditional medicine for the treatment of various diseases. At present, there are a variety of marketed preparations with it as the main medicine on the market. Information regarding the in vivo process of it is lacking, which has become a bottleneck restricting its development and utilization. In view of this, a GC-MS SIM analysis method was established for the simultaneous determination of six main volatile components [eucalyptol, p-cymene, 4-carvomenthenol, 4-isopropyl-2-cyclohexenone, α-terpineol, and 2-(4-Methylphenyl)-propan-2-ol] in plasma and ten tissues of rats to study their pharmacokinetic and distribution characteristics in vivo. The pharmacokinetic results showed that the t1/2 of each index was 0.41-1.66 h, Tmax was 0.16-0.68 h, Cmax was 13.66-2015.02 ng/mL, AUC0-t was 12.84-4299.00 h·ng/mL, CLZ/F was 1750.93-107013.11 mL/h/kg. This meant that the six components could be absorbed quickly, had a short residence time, and be eliminated quickly in the body. Among them, eucalyptol has the highest degree of absorption and a larger amount of entering the body. Moreover, the Cmax and AUC0-t of the six components increased correspondingly with the increase of the dose, indicating that the concentration of Oleum Cinnamomi in the rat plasma was dose-dependent. At different time points, the six components were widely distributed with uneven characteristics in the body. The six components mainly tend to be distributed in stomach, small intestine, and liver, followed by kidney, spleen, heart, and brain, and to a lesser extent in lung, skin, and muscle. And the six components were eliminated quickly in each tissue. The pharmacokinetic process and tissue distribution characteristics of Oleum Cinnamomi were expounded in this study, which can provide scientific theory for the in-depth development and guidance of clinical drug use of Oleum Cinnamomi, and at the same time provide a medicinal material basis for the in-depth development and utilization of Oleum Cinnamomi.

Effects of dietary coated-oleum cinnamomi supplementation on the immunity and intestinal integrity of broiler chickens.

Oleum cinnamomi (OCM) is increasingly used as a feed additive in animal diets. The aim of this study was to investigate the effects of dietary supplementation with coated-OCM (cOCM) on the immunity and intestinal integrity of broiler chickens. A total of 396 one-day-old chicks were randomly assigned into six groups. The basal diets were supplemented with 50 mg/kg of flavomycin (positive control) as well as 0 (control), 50, 100, 200, and 300 mg/kg of cOCM. Compared with the control, both positive control and cOCM treatments did not improve the growth performance. Serum immunoglobulin (Ig) Y levels were decreased by flavomycin and 50 mg/kg of cOCM treatments (p < 0.05). Dietary cOCM decreased ileal secretory IgA contents at d 21 and commonly down-regulated duodenal and ileal mRNA expression of interleukin (IL)-1ß and IL-8 at d 42 (p < 0.05). The 300 mg/kg of cOCM increased jejunal ratio of villus height to crypt depth and upregulated intestinal claudin-1 expression (p < 0.05). Jejunal (at d 21) and duodenal (at d 42) mucin-2 expression was up and downregulated by both 50 and 300 mg/kg of cOCM, respectively (p < 0.05). In conclusion, dietary cOCM addition helped to maintain noninflammatory states of humoral and mucosal immunity, and improved the intestinal integrity of broiler chickens.