An Absorption and Plasma Kinetics Study of Monoterpenes Present in Mastiha Oil in Humans

Evaluation of the Effect of Pistacia atlantica Oleoresin on Blood Sugar, Pressure and Lipids in Patients With Type 2 Diabetes: A Single-Blind, Placebo-Controlled Trial

BACKGROUND

Diabetes mellitus (DM) is a chronic metabolic disorder characterised by high blood sugar (BS) levels due to impaired insulin production or insulin resistance. It is a global health concern with significant implications for morbidity and mortality. Persian medicine has long utilised natural remedies, such as Pistacia atlantica Desf., for various diseases. In this randomised clinical trial, the effects of P. atlantica oleoresin in the improvement of lipid profiles, glucose indices and blood pressure (BP) were assessed in patients with Type 2 DM.

MATERIALS AND METHODS

In this randomised, single-blind, placebo-controlled study, 42 patients with Type 2 DM were randomly allocated to receive either P. atlantica oleoresin or placebo capsule for 3 months. Patients were evaluated prior to and 12 weeks after the beginning of the intervention, in terms of changes in lipid profiles, glucose indices and BP.

RESULTS

After 3 months, the mean BP in patients with DM receiving P. atlantica oleoresin was significantly reduced compared with the baseline (p = 0.001). Also, these changes were significantly higher than those of the control group. The mean of total cholesterol (p = 0.89), low-density lipoprotein (LDL) (p = 0.43) and triglyceride (TG) (p = 0.98) in the intervention group after 3 months was lower than that in the control group, but this difference was not statistically significant.

CONCLUSION

After 3 months, there was no significant difference between the P. atlantica and control groups in terms of blood sugar and lipid profiles. The mean BP in patients with DM receiving P. atlantica oleoresin was significantly reduced compared with that in the beginning of the study. Also, these changes were significant compared with the control group.

Effects of Chios Mastiha essential oil on cholesterol levels of healthy volunteers: A prospective, randomized, placebo-controlled study (MASTIHA-OIL)

INTRODUCTION

Chios Mastiha essential oil (CMO) is a natural product extracted from the resin of Mastiha, possessing antioxidant, anti-microbial, anti-ulcer, anti-neoplastic, and cholesterol-lowering capabilities in vitro, and its hypolipidemic effect was confirmed in animal studies. Yet, there are no randomized, placebo-controlled clinical studies in the literature regarding CMO's hypolipidemic effects in humans. A prospective, randomized, placebo-controlled study was designed to study the hypolipidemic effect of CMO capsules on healthy volunteers with elevated cholesterol.

METHODS

192 healthy volunteers were screened and 160 of them with total cholesterol> 200 mg/dl participated in the study. They were randomized with a 2:1 ratio of receiving CMO capsules (200 mg mastiha-oil/capsule) and placebo for 8 weeks respectively. 113 patients received CMO and 47 were randomized in the control group, and all of them completed the follow-up period.

RESULTS

After 8 weeks of CMO administration, total and LDL cholesterol were significantly lower in the CMO compared to the placebo group 215.2 ± 27.5 vs 237.0 ± 27.9 mg/dl (p < 0.001) and 135.0 ± 26.1 vs 153.0 ± 23.3 mg/dl (p < 0.001) respectively. No gastrointestinal adverse events or liver or renal toxicity were reported. Additionally, in the CMO group total cholesterol was significantly decreased by 20.6 mg/dl (9%), LDL by 18.1 mg/dl (12%), triglycerides by 21.8 mg/dl (15%), and glucose by 4.6 mg/dl (5%) and HDL was increased by 2.4 mg/dl (5%), compared to their baseline values.

CONCLUSION

The MASTIHA-OIL study showed the efficacy and safety of CMO in reduction of total and LDL cholesterol after 8 weeks of administration in healthy volunteers with elevated cholesterol levels.

Analysis of the volatile monoterpene composition of citrus essential oils by photoelectron spectroscopy employing continuously monitored dynamic headspace sampling

A new photoelectron spectroscopic method permitting a quantitative analysis of the volatile headspace of several essential oils is presented and discussed. In particular, we focus on the monoterpene compounds, which are known to be the dominant volatile components in many such oils. The photoelectron spectra of the monoterpene constituents may be effectively isolated by accepting for analysis only those electrons that accompany the production of m/z = 136 ions, and by using low photon energies that restrict cation fragmentation. The monoterpene isomers are then identified and quantified by regression modelling using a library of terpene standard spectra. An advantage of this approach is that pre-concentration of the volatile vapour is not required, and all steps are performed at ambient temperature, avoiding the possible deleterious effects (such as isomerisation/decomposition) that may sometimes arise in gas chromatographic (GC) procedures. As a proof-of-principle demonstration, three citrus oils (lemon, lime, bergamot) are analysed with this approach and the results are compared with reported GC composition profiles obtained for these oils. Potential advantages of the methodology that include multiplex detection and real-time, in situ analysis are identified and discussed. Alternative and faster experimental implementations concerning laboratory-based ionization and detection schemes are proposed and considered, as is the possibility of a straightforward extension towards simultaneous determination of enantiomeric excesses.

Association of exposures to serum terpenes with the prevalence of dyslipidemia: a population-based analysis

This study sought to examine hitherto unresearched relationships between serum terpenes and the prevalence of dyslipidemia. Serum terpenes such as limonene, α-pinene, and β-pinene from the 2013-2014 National Health and Nutrition Examination Survey (NHANES) were used as independent variables in this cross-sectional study. Continuous lipid variables included total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), non-HDL-C, triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), residual cholesterol (RC), and apolipoprotein B (Apo B). Binary lipid variables (elevated TC, ≥5.18 mmol/L; lowered HDL-C, <1.04 mmol/L in men, and <1.30 mmol/L in women; elevated non-HDL-C, ≥4.2 mmol/L; elevated TG, ≥1.7 mmol/L; elevated LDL-C, ≥3.37 mmol/L; elevated RC, ≥1.0 mmol/L; and elevated Apo B, ≥1.3 g/L) suggest dyslipidemia. The relationships between the mixture of serum terpenes with lipid variables were investigated using weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR). The study for TC, HDL-C, and non-HDL-C included a total of 1,528 people, whereas the analysis for TG, LDL-C, RC, and Apo B comprised 714 participants. The mean age of the overall participants was 47.69 years, and 48.77% were male. We found that tertiles of serum terpene were positively associated with binary (elevated TC, non-HDL-C, TG, LDL-C, RC, Apo B, and lowered HDL-C) and continuous (TC, non-HDL-C, TG, LDL-C, RC, and Apo B, but not HDL-C) serum lipid variables. WQS regression and BKMR analysis revealed that the mixture of serum terpenes was linked with the prevalence of dyslipidemia. According to our data, the prevalence of dyslipidemia was correlated with serum concentrations of three terpenes both separately and collectively.

Chios mastiha essential oil exhibits antihypertensive, hypolipidemic and anti-obesity effects in metabolically unhealthy adults - a randomized controlled trial

The essential oil of the resinous exudate from Pistacia lentiscus of Chios namely Chios Mastiha Essential Oil (CMEO), is a natural volatile oil rich in monoterpenes α-pinene, β-myrcene, β-pinene. In the present randomized controlled trial, we investigated the effects of CMEO on individuals with abdominal obesity and metabolic abnormalities i.e., dyslipidemia, hypertension, insulin resistance. Eligible patients (N = 94) were randomly assigned to either the intervention group, receiving capsules containing 200 mg of CMEO daily for 3 months adjunct to current treatment for metabolic disorder(s), or the control group. Anthropometric measurements, blood markers, and quality of life (QoL) were assessed. Statistical analysis was performed on an intention-to-treat basis. A significant improvement in blood lipid profile, namely triglycerides (p = 0.026) and low-density lipoprotein (p = 0.05) of the CMEO group versus controls was observed. Systolic blood pressure (p = 0.05) and alanine aminotransferase (p = 0.022) significantly decreased only after CMEO intake. Alike, weight decreased only in CMEO (p = 0.02), while mean changes in % body fat (p = 0.005) and visceral fat (p = 0.045) were significantly different between groups post-intervention. Lower oxidized LDL (p = 0.044) and higher adiponectin (p = 0.007) were recorded in CMEO with significant different mean changes between groups post-intervention. QoL, as assessed by Short Form-12 questionnaire was improved in the CMEO compared to control (p = 0.041 for Physical Composite Score, p = 0.035 for Mental Composite Score). No adverse effects were reported. An anti-obesity effect of CMEO, probably attributed to modulation of inflammatory and antioxidant processes, is suggested. Conclusively, CMEO can be safe and effective in regulating metabolic abnormalities, adjunct to treatment. (ClinicalTrials.gov. The effect of Mastiha oil in Metabolic Syndrome, ID Number: NCT04785573).

Safety assessment of herbal supplement components targeting hepatotoxicity and CYP3A4 induction in cell-based assay using HepG2 cells

Herbal supplements can cause hepatotoxicity and drug interactions via hepatic cytochrome P-450 (CYP) in some cases. However, there is no simple and stable cell-based assay to conduct a screening for hepatotoxicity and CYP induction. In the present study, we selected 14 components of the herbal supplement based on our previous reports and investigated the safety of the herbal supplement components focusing on toxicity and CYP3A4 induction in a cell-based assay using HepG2. The toxicity of the components was examined by lactate dehydrogenase (LDH) and cell proliferation assays. Then, the CYP3A4 induction of the components were examined by a reporter assay using reporter vectors of CYP3A4. The vector includes the CYP3A4 proximal promoter (CYP3A4PP) and the xenobiotic-responsive enhancer module (XREM) regions. Luteolin (LU) significantly increased LDH activity and decreased cell proliferation activity that suggests LU may cause toxicity in HepG2 cells. Quercetin (QU) increased the transcriptional activity of CYP3A4 (1.5-fold of control) in the reporter assay. However, the induction of QU was slightly in comparison to the validation of the transcriptional activity of CYP3A4 treated with CYP3A4 inducers. The CYP3A4 induction of QU may not involve CYP3A4PP but involves the XREM response. Throughout our results, the method in the present study may be useful for a safety assessment of herbal supplements, primarily focusing on hepatotoxicity and CYP3A4 induction. PRACTICAL APPLICATION: Even though there are problems with herbal supplements, studies related to toxicity are not actively carried out. The present methods may apply to the safety assessment for herbal supplements and be useful for the prevention and verification of health hazards caused by herbal supplements (the summary is shown in Figure S2).

Editorial for the Special Issue, “Chemistry of Essential Oils and Food Flavours”

Essential oils have important functions in nature [...]

Medicinal Plants and Their Impact on the Gut Microbiome in Mental Health: A Systematic Review

Background: Various neurocognitive and mental health-related conditions have been associated with the gut microbiome, implicating a microbiome–gut–brain axis (MGBA). The aim of this systematic review was to identify, categorize, and review clinical evidence supporting medicinal plants for the treatment of mental disorders and studies on their interactions with the gut microbiota. Methods: This review included medicinal plants for which clinical studies on depression, sleeping disorders, anxiety, or cognitive dysfunction as well as scientific evidence of interaction with the gut microbiome were available. The studies were reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Results: Eighty-five studies met the inclusion criteria and covered thirty mental health-related medicinal plants with data on interaction with the gut microbiome. Conclusion: Only a few studies have been specifically designed to assess how herbal preparations affect MGBA-related targets or pathways. However, many studies provide hints of a possible interaction with the MGBA, such as an increased abundance of health-beneficial microorganisms, anti-inflammatory effects, or MGBA-related pathway effects by gut microbial metabolites. Data for Panax ginseng, Schisandra chinensis, and Salvia rosmarinus indicate that the interaction of their constituents with the gut microbiota could mediate mental health benefits. Studies specifically assessing the effects on MGBA-related pathways are still required for most medicinal plants.

GC-MS Method for Quantification and Pharmacokinetic Study of Four Volatile Compounds in Rat Plasma after Oral Administration of Commiphora myrrh (Nees) Engl. Resin and In Vitro Cytotoxic Evaluation

A rapid, simple, and sensitive gas chromatography–tandem mass spectrometry (GC–MS) method was established and validated for simultaneous determination of four volatile compounds, namely curzerene, methoxyfuranodiene, β-elemene, and α-pinene in rat plasma samples after oral administration of the resin extract of Commiphora myrrh using limonene as an internal standard (IS). Liquid-liquid extraction using hexane and ethyl acetate (1:1) mixture as an extracting agent was used for the samples extraction procedure. The GC–MS system was operated under selective ion monitoring (SIM) mode using Perkin Elmer Elite 5MS column (30 m × 0.25 mm × 0.25 µm film thickness). Specificity, linearity, precision, accuracy, extraction recovery, and stability were used to validate the developed method. The assay showed good linearity (r2 ≥ 0.998), and the lowest limits of quantification (LLOQ) were 3.97–21.38 ng/mL for the four analytes. This assay was successfully applied to pharmacokinetic studies of the four volatile compounds in rat plasma. The antiproliferative activity of these volatile compounds was evaluated against lung carcinoma (A549) and colon (LoVo) cell lines, were each compound caused variable inhibition on cells proliferation and methoxyfuranodiene exerted the strong antiproliferative activity against both cell line according to IC50 values.

Myrcene-What Are the Potential Health Benefits of This Flavouring and Aroma Agent?

Myrcene (β-myrcene) is an abundant monoterpene which occurs as a major constituent in many plant species, including hops and cannabis. It is a popular flavouring and aroma agent (food additive) used in the manufacture of food and beverages. This review aims to report on the occurrence, biological and toxicological profile of β-myrcene. The main reported biological properties of β-myrcene-anxiolytic, antioxidant, anti-ageing, anti-inflammatory, analgesic properties-are discussed, with the mechanisms of activity. Here we also discuss recent data regarding the safety of β-myrcene. Overall, β-myrcene has shown promising health benefits in many animal studies. However, studies conducted in humans is lacking. In the future, there is potential for the formulation and production of non-alcoholic beers, functional foods and drinks, and cannabis extracts (low in THC) rich in β-myrcene.

Antioxidant and Cytoprotective Potential of the Essential Oil Pistacia lentiscus var. chia and Its Major Components Myrcene and α-Pinene

The antioxidant, cytoprotective, and wound-healing potential of the essential oil from the resin of Pistacia lentiscus var. chia (mastic oil) was evaluated, along with that of its major components, myrcene and α-pinene. Antioxidant potential was monitored as: (i) direct antioxidant activity as assessed by 2,2-di-phenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), and ABTS assays; (ii) DNA damage protection activity; and (iii) cytoprotective activity as assessed via induction of transcription of genes related to the antioxidant response in human keratinocyte cells (HaCaT). The cytoprotective potential of the test substances was further evaluated against ultraviolet radiation B (UVB)- or H₂O₂-induced oxidative damage, whereas their regenerative capability was accessed by monitoring the wound closure rate in HaCaT. Μastic oil and major components did not show significant direct antioxidant activity, however they increased the mRNA levels of antioxidant response genes, suggesting indirect antioxidant activity. Treatment of HaCaT with the test substances before and after UVB irradiation resulted in increased cell viability in the cases of pre-treatment with mastic oil or post-treatment with myrcene. Increased cytoprotection was also observed in the case of cell treatment with mastic oil or its major components prior to H₂O₂ exposure. Finally, mastic oil and myrcene demonstrated a favorable dose-dependent effect for cell migration and wound closure. Collectively, mastic essential oil may exert its promising cytoprotective properties through indirect antioxidant mechanisms.