HPLC method for simultaneous determination of retinol, alpha-tocopherol and coenzyme Q10 in human plasma

Concepts and principles for new rapid simple liquid chromatography method for quantification of antioxidants resveratrol, vitamin E, and coenzyme Q10 in capsules with high-performance liquid chromatography with a photo-diode array detector

Principles and problems in the development of simultaneous liquid chromatography (LC) analytical methods for potent antioxidative molecules resveratrol, tocopherol, and coenzyme Q10 in capsules, have been investigated and systematically compared and summarized. For these purposes, experiments within the full polarity spectrum of LC techniques. were tested and recorded. The whole range of polarities included: Alkyl C18 bonded reversed phase, phenyl, cyanopropyl, diol, and the most polar base silica-filled column matrixes have been used. The summarized results concluded that all mentioned LC techniques could be used for the determination of the mentioned group of the three analytes with different run characteristics and efficiency. These successes could be achieved after careful analyses of molecular physicochemical data of analytes. They are especially organic solubilities. The ultraviolet spectral absorption characteristics of each analyte and the mobile phase constituents for appropriate separation were very important to be known. The ultimate targets were the development method with the isocratic mode of separation yielding symmetrical peak shapes for the best sensitivity and accuracy, with the shortest run time and best reproducibility. From an analytical point of view important for LC, the three analytes have quite distinct characteristics that contribute to successful method development. These features are their organic solvent and water solubility, molecular polarities, and ultraviolet-absorption characteristics, like spectra and absorptivities. All these mentioned parameters were taken into account for solving complications appearing in the development of rapid LC methods for the simultaneous determination of three antioxidant molecules.

Effects of arginine on coenzyme-Q10 micelle uptake for mitochondria-targeted nanotherapy in phenylketonuria

Phenylketonuria (PKU) is a rare inherited metabolic disease characterized by phenylalanine hydroxylase enzyme deficiency. In PKU patients, coenzyme Q10 (CoQ10) levels were found low. Therefore, we focused on the modification of CoQ10 to load the micelles and increase entry of micelles into the cell and mitochondria, and it is taking a part in ATP turnover. Micelles had produced by comparing two different production methods (thin-film layer and direct-dissolution), and characterization studies were performed (zeta potential, size, and encapsulation efficiency). Then, L-arginine (LARG) and poly-arginine (PARG) were incorporated with the micelles for subsequential release and PKU cell studies. The effects of these components on intracellular uptake and their use in the cellular cycle were analyzed by ELISA, Western blot, membrane potential measurement, and flow cytometry methods. In addition, both effects of LARG and PARG micelles on pharmacokinetics at the cellular level and their cell binding rate were determined. The thin-film method was found superior in micelle preparation. PARG/LARG-modified micelles showed sustained release. In the cellular and mitochondrial uptake of CoQ10, CoQ10-micelle + PARG > CoQ10-micelle + LARG > CoQ10-micelle > CoQ10 was found. This increased localization caused lowering of oxygen consumption rates, but maintaining mitochondrial membrane potential. The study results had showed that besides micelle formulation, PARG and LARG are effective in cellular and mitochondrial targeting.

Inherited causes of exocrine pancreatic insufficiency in pediatric patients: clinical presentation and laboratory testing

Pediatric patients with exocrine pancreatic insufficiency (EPI) have symptoms that include abdominal pain, weight loss or poor weight gain, malnutrition, and steatorrhea. This condition can be present at birth or develop during childhood for certain genetic disorders. Cystic fibrosis (CF) is the most prevalent disorder in which patients are screened for EPI; other disorders also are associated with pancreatic dysfunction, such as hereditary pancreatitis, Pearson syndrome, and Shwachman-Diamond syndrome. Understanding the clinical presentation and proposed pathophysiology of the pancreatic dysfunction of these disorders aids in diagnosis and treatment. Testing pancreatic function is challenging. Directly testing aspirates produced from the pancreas after stimulation is considered the gold standard, but the procedures are not standardized or widely available. Instead, indirect tests are often used in diagnosis and monitoring. Although indirect tests are more widely available and easier to perform, they have inherent limitations due to a lack of sensitivity and/or specificity for EPI.

Nutritional Status and Circulating Levels of Fat-Soluble Vitamins in Cystic Fibrosis Patients: A Cohort Study and Evaluation of the Effect of CFTR Modulators

BACKGROUND

Improved therapy in CF has led to an overall improvement in nutritional status. The objectives of our study are: to cross-sectionally assess nutritional status and serum levels of fat-soluble vitamins; to retrospectively evaluate the efficacy of modulators on nutritional status and fat-soluble vitamin levels.

METHODS

In patients younger than 2 years of age, we evaluated growth, in patients aged 2-18 years, we assessed BMI z-scores, and in adults, we assessed absolute BMI values. Levels of 25(OH)D, vitamins A, and E were measured.

RESULTS

A cross-sectional analysis was conducted on 318 patients, 109 (34.3%) with pancreatic sufficiency. Only three patients were under 2 years old. In 135 patients aged 2-18 years, the median BMI z-score was 0.11, and 5 (3.7%) patients had malnutrition (z-score ≤ 2SD). In 180 adults, the median BMI was 21.8 kg/m². Overall, 15 (13.7%) males (M) and 18 (25.3%) females (F) were underweight (18 < BMI > 20); 3 (2.7%) M and 5 (7.0%) F had a BMI < 18. Suboptimal 25(OH)D levels were found in patients with pancreatic insufficiency. The prevalence of deficiency of vitamins A and E is low. After one year of treatment with modulators, the increase in BMI was more consistent (M: 1.58 ± 1.25 kg/m² F: 1.77 ± 1.21 kg/m²) in elexacaftor/tezacaftor/ivacaftor (ETI)-treated patients compared with other modulators, with a significant increase in levels of all fat-soluble vitamins.

CONCLUSIONS

Malnutrition is present in a limited number of subjects. The prevalence of subjects with suboptimal 25(OH)D levels is high. ETI showed a beneficial effect on nutritional status and circulating levels of fat-soluble vitamins.

Comparative Studies of Selected Criteria Enabling Optimization of the Extraction of Polar Biologically Active Compounds from Alfalfa with Supercritical Carbon Dioxide

The aim of this research was to provide crucial and useful data about the selection of the optimization criteria of supercritical carbon dioxide extraction of alfalfa at a quarter-technical plant. The correlation between more general output, including total phenolics and flavonoids content, and a more specified composition of polar constituents was extensively studied. In all alfalfa extracts, polar bioactive constituents were analyzed by both spectrometric (general output) and chromatographic (detailed output) analyses. Eight specific phenolic acids and nine flavonoids were determined. The most dominant were salicylic acid (221.41 µg g⁻¹), ferulic acid (119.73 µg g⁻¹), quercetin (2.23 µg g⁻¹), and apigenin (2.60 µg g⁻¹). For all seventeen analyzed compounds, response surface methodology and analysis of variance were used to provide the optimal conditions of supercritical fluid extraction for each individual constituent. The obtained data have shown that eight of those compounds have a similar range of optimal process parameters, being significantly analogous for optimization based on total flavonoid content.

Effect of Statin Therapy on the Plasma Concentrations of Retinol, Alpha-Tocopherol and Coenzyme Q10 in Children with Familial Hypercholesterolemia

Purpose

Familial hypercholesterolemia (FH) requires early treatment. However, statins, which are regarded the first-line therapy, have an influence on redox balance. Antioxidant vitamins are important for many metabolic processes in the developing body. There are few data available on the long-term safety of statin use in children. The aim of this study was to evaluate the influence of statin treatment in children with FH on plasma concentrations of antioxidant vitamins: retinol, alpha-tocopherol and coenzyme Q10.

Methods

The first study group consisted of 13 children aged 10–18 years treated with simvastatin for at least 6 months, and the second group comprised 13 age- and sex-matched children with hypercholesterolemia, in whom pharmacological treatment had not been applied yet. Analyses were performed using a high-performance liquid chromatograph coupled with a MS detector.

Results

The analysis did not reveal significant differences in the concentration of retinol, alpha-tocopherol or coenzyme Q10 between the studied groups. The adjustment of the concentrations of the vitamins to the cholesterol level also indicated no significant differences. We found no deficits in antioxidant vitamins in patients treated with statins, or any risk of adverse effects associated with an increase in their concentration.

Conclusion

There is no rationale for additional supplementation using antioxidant vitamins or modification of low-fat and low-cholesterol diet in pediatric patients treated with statins.

Electronic supplementary material

The online version of this article (10.1007/s10557-020-07091-w) contains supplementary material, which is available to authorized users.

[Relationship between serum vitamin E concentration in first trimester and the risk of developing hypertension disorders complicating pregnancy]

OBJECTIVE

To investigate the incidence of hypertension disorders complicating pregnancy (HDCP) and vitamin E (VE) nutritional status among pregnant women in Beijing, and to determine the relationship between serum VE concentration in the first trimester of pregnancy and the risk of developing HDCP.

METHODS

A retrospective cohort study was performed including 22 283 cases of pregnant women who underwent singleton deliveries in Tongzhou Maternal & Child Health Hospital of Beijing from January 2016 through December 2018 and received tests of serum VE concentrations in the first trimester of pregnancy. Nonconditional Logistic regression model was used to analyze the association between serum VE concentration levels and the risk of developing HDCP.

RESULTS

The total incidence of HDCP was 5.4%, with the incidence of gestational hypertension around 2.1% and the incidence of preeclampsia-eclampsia around 3.3%. The median concentration of serum VE in early pregnancy was 10.1 (8.8-11.6) mg/L, and 99.7% of the participants had normal serum VE concentrations. The incidence of gestational hypertension and that of preeclampsia-eclampsia had been annually increasing in three years; a linear-by-linear association had also been observed between the serum VE concentrations and the years of delivery. According to the results of the univariable and the multivariable Logistic regression analyses, higher risks of developing HDCP had been observed among women with higher serum VE concentrations. Compared to those with serum VE concentrations in interquartile range (P25-P75) of all the participants, the women whose serum VE concentrations above P75 were at higher risks to be attacked by HDCP (OR = 1.34, P < 0.001), gestational hypertension (OR = 1.39, P = 0.002), or preeclampsia-eclampsia (OR = 1.34, P = 0.001), as suggested by the results of the multivariable Logistic regression model analyses. In addition, the women with serum VE concentrations of 11.2 mg/L or above had a significantly higher risk of developing HDCP than those whose serum VE concentrations of P40-P60 of all the participants, and this risk grew higher as serum VE concentrations in the first trimester of pregnancy increased.

CONCLUSION

Women in Beijing are at good nutritional status. From January 2016 to December 2018, the incidence of HDCP increased with serum VE concentration level, and serum VE concentration of 11.2 mg/L is an indicator of an increased risk of developing HDCP, suggesting that pregnant women should take nutritional supplements containing VE carefully.

Simultaneous analysis of retinol, six carotenoids, two tocopherols, and coenzyme Q10 from human plasma by HPLC

Lipophilic antioxidant determination is of relevance in health and diseases. Several HPLC methods exists but rare are those including coenzyme Q10 with carotenoids, retinol and tocopherols. Here a single-step extraction was proposed for the detection of retinol, α and γ-tocopherols, lutein, zeaxanthin, trans-ß-carotene, α-carotene, ß-cryptoxanthin and lycopene as well as coenzyme Q10. A single HPLC column was used and UV-vis diode array detection was performed. Echinenone, alpha-tocopherol nicotinate and coenzyme Q4 were employed as internal standards. Intra-assay and inter-assay precision were respectively 1.4-7.9% and 2.2-15.8%. Accuracy was validated using SRM 968e. LOD (limit of detection) and LOQ (limit of quantification) obtained were sufficient for nutritional epidemiological study and routine clinical application.

Systemic Redox Imbalance in Patients with Chronic Granulomatous Disease

The aim of our study was to evaluate redox status, enzymatic and non-enzymatic antioxidant barriers, oxidative damage of proteins, lipids and DNA, as well as concentration of coenzyme Q10 and vitamins A and E in patients with chronic granulomatous disease (CGD). The study was performed on fifteen Caucasian individuals (median age 24 years and seven months) diagnosed with CGD. The mutation in the NCF1 gene was confirmed in ten patients, and in the CYBB gene in five patients. We demonstrated high levels of total oxidant status (TOS) and oxidative stress index (OSI), lipids (↑8-isoprostanes (8-isoP), ↑4-hydroxynonenal (4-HNE)), proteins (↑advanced oxidation protein products (AOPP)) and DNA (↑8-hydroxy-2’-deoxyguanosine (8-OHdG)) oxidation products in CGD individuals as compared to sex- and age-matched healthy controls. We showed enhanced serum enzymatic activity of catalase (CAT) and superoxide dismutase-1 (SOD) and significantly decreased coenzyme Q10 concentration. Our study confirmed redox disturbances and increased oxidative damage in CGD patients, and indicated the need to compare redox imbalance depending on the type of mutation and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity. The question regarding effectiveness of antioxidant therapy in patients with CGD is open, and the need to establish guidelines in this area remains to be addressed.

The risks of ubiquinone and β-carotene deficiency and metabolic disorders in patients with oral cancer

Background

Cancer development is mediated by oxidative stress and inflammation, which may correlate with metabolic disorders. The aim of this study was to evaluate antioxidant vitamins status and metabolic parameters in patients with oral cancer according to tumor-node-metastasis (TNM) stages.

Methods

A total of 194 patients with oral cancer were enrolled in this study. The patients were stratified for four groups according to cancer stages and that the statistics are comparisons across these groups. The levels of antioxidant vitamins (ubiquinone, β-carotene, vitamin A and E), metabolic parameters, oxidative stress, antioxidant enzymes activity, and inflammatory markers were measured.

Results

More than half of the subjects had high blood pressure, central obesity, hyperglycemia, and hyperlipidemia regardless of TNM stage. With regard to antioxidant vitamins status, 46 and 94% of patients had β-carotene and ubiquinone deficiency, respectively. Patients in T3 and T4 stages had significantly lower antioxidant enzyme (catalase, p = 0.03) activity and higher inflammatory markers levels (high sensitivity C-reactive protein and interleukin-6, p < 0.01) than patients in the other stages. In addition, the level of β-carotene was negatively associated with waist circumference, and ubiquinone was positively associated with the level of high-density lipoprotein cholesterol (p < 0.05). Higher β-carotene and ubiquinone levels were negatively associated with hypertriglyceridemia and the risk of metabolic syndrome (p < 0.05).

Conclusions

A high proportion of patients with oral cancer had ubiquinone or β-carotene deficiency and metabolic disorders. The level of ubiquinone or β-carotene was negatively associated with the risk of central obesity, hypertriglyceridemia, and metabolic syndrome. Since patients with oral cancer suffer from high oxidative stress and inflammation (particularly in the T3 and T4 stages), supplementation with antioxidant vitamins such as ubiquinone or β-carotene could be preferentially applied.

Analytical Method Development for Coq10 Determination in Human Plasma Using HPLC-UV and HPLC/MS/MS

Background:

CoQ10 is a very important compound which is found in every tissue of our organism. It participates in the processes of cellular respiration and ATP production. Also, it acts as a strong antioxidant. In an organism, it is represented in two forms: oxidized (ubiquinone) and reduced (ubiquinol). Its low blood level may be a signal for a list of diseases.

Materials and Methods:

This study developed and compared two methods of CoQ10 determination in order to find the fastest and the most convenient one. The first one involved HPLC-UV with the wavelength of ubiquinone determination equivalent to 290 nm and 275 nm for ubiquinol, respectively. The second one was carried out on an HPLC/MS/MS system utilizing Electrospray Ionization (ESI) and triple quadrupole mass analyzer for quantification in MRM positive mode.

Results:

Two methods of ubiquinol and ubiquinone determination were developed and validated. HPLC-UV included sample preparation based on liquid-liquid extraction. The LLOQ was 0.50 µg/ml. HPLC-MS/MS method sample preparation was based on protein precipitation. The LLOQ was 0.10 µg/ml.

Conclusion:

During the investigation, a conclusion was drawn that the HPLC-UV method is too insensitive for simultaneous determination of ubiquinol and ubiquinone. Furthermore, ubiquinol is very unstable and during exogenous factors’ exposure, it rapidly turns into ubiquinone. While, the HPLCMS/ MS method turned out to be sensitive, selective, rapid as it provides an accurate determination of both forms of CoQ10 in spiked human plasma.

Effects of coenzyme Q10 supplementation on the serum levels of amylase, adenosine deaminase, catalase, and total antioxidant capacity in women with type 2 diabetes mellitus: A randomized, double-blind placebo-controlled trial

Background:

Increased levels of reactive oxygen species is a key factor involved in the pathogenesis of type 2 diabetes mellitus (T2DM). Coenzyme Q₁₀ (CoQ₁₀) is a nonenzymatic antioxidant that restores other antioxidants.

Materials and Methods:

This randomized, double-blind placebo-controlled trial study has been designed to evaluate the effects of CoQ₁₀ supplementation on serum values of amylase, adenosine deaminase, catalase (CAT), total antioxidant capacity (TAC) and the quantitative insulin sensitivity check index (QUICKI) in women with T2DM. Serum levels of CoQ₁₀ were measured too. Sixty-eight women with T2DM were enrolled in this study and randomly divided into two groups. One group received 100 mg/day of CoQ₁₀ supplement for 12 weeks (n = 34), and the other group was given placebo for the same time duration and dosage (n = 34).

Results:

After the intervention, serum CAT activity (P < 0.001), TAC (P = 0.006), CoQ₁₀ (P = 0.001), and QUICKI (P = 0.005) increased and fasting blood sugar (FBS) (P = 0.05) decreased significantly in CoQ₁₀ group.

Conclusion:

This study showed that daily supplementation with 100 mg of CoQ₁₀ could increase TAC and CAT activity as, CoQ₁₀ and QUICKI and could reduce oxidative stress and FBS in women with T2DM.

α-Tocopherol influences glycaemic control and miR-9-3 DNA methylation in overweight and obese women under an energy-restricted diet: a randomized, double-blind, exploratory, controlled clinical trial

Background

Excess weight is a strong risk factor for the development of dysglycaemia. It has been suggested that changes in the metabolism microRNAs, small non-coding RNAs that regulate gene expression, could precede late glycaemic changes. Vitamin E in turn may exert important functions in methylation and gene expression processes. This study aimed to determine the effect of α-tocopherol on glycaemic variables and miR-9-1 and miR-9-3 promoter DNA methylation in overweight women.

Methods

A randomized, double-blind, exploratory, placebo-controlled study was conducted in overweight and obese adult women (n = 44) who ingested synthetic vitamin E (all-rac-α-tocopherol), natural source vitamin E (RRR-rac-α-tocopherol) or placebo capsules and were followed up for a period of 8 weeks. Supplemented groups also received dietary guidance for an energy-restricted diet. An additional group that received no supplementation and did not follow an energy-restricted diet was also followed up. The intervention effect was evaluated by DNA methylation levels (quantitative real-time PCR assay) and anthropometric and biochemical variables (fasting plasma glucose, haemoglobin A1C, insulin, and vitamin E).

Results

Increased methylation levels of the miR-9-3 promoter region (P < 0.001) and reduced haemoglobin A1C (P < 0.05) were observed in the natural source vitamin E group after intervention. Increased fasting plasma glucose was observed in the synthetic vitamin E group, despite the significant reduction of anthropometric variables compared to the other groups.

Conclusions

α-Tocopherol from natural sources increased methylation levels of the miR-9-3 promoter region and reduced haemoglobin A1C in overweight women following an energy-restricted diet. These results provide novel information about the influence of vitamin E on DNA methylation.

Trial registration

ClinicalTrials.gov, NCT02922491. Registered 4 October, 2016.

Electronic supplementary material

The online version of this article (10.1186/s12986-018-0286-7) contains supplementary material, which is available to authorized users.

Highly sensitive and selective determination of redox states of coenzymes Q9 and Q10 in mice tissues: Application of orbitrap mass spectrometry

Coenzyme Q (CoQ) is a redox active molecule that plays a fundamental role in mitochondrial energy generation and functions as a potent endogenous antioxidant. Redox ratio of CoQ has been suggested as a good marker of mitochondrial dysfunction and oxidative stress. Nevertheless, simultaneous measurement of redox states of CoQ is challenging owing to its hydrophobicity and instability of the reduced form. In order to improve the analytical methodology, paying special attention to this instability, we developed a highly sensitive and selective high-resolution/accurate-mass (HR/AM) UHPLC-MS/MS method for the rapid determination of redox states of CoQ₉ and CoQ₁₀ by ultra-performance liquid chromatography-hybrid quadrupole-Orbitrap mass spectrometry. CoQs were extracted using hexane with the addition of butylated hydroxytoluene to limit oxidation during sample preparation. Chromatographic separation of the analytes was achieved on a Kinetex C₁₈ column with the isocratic elution of 5 mM ammonium formate in 2-propanol/methanol (60:40) within 4 min. A full MS/all ion fragmentation (AIF) acquisition mode with mass accuracy < 5 ppm was used for detection and determination of redox states of CoQ₉ and CoQ₁₀ in healthy mice tissues using reduced and oxidized CoQ₄ as internal standards. The validated method showed good linearity (r² ≥ 0.9991), intraday, inter-day precision (CVs ≤ 11.9%) and accuracy (RE ≤±15.2%). In contrast to existing methods, the current method offers enhanced sensitivity (up to 52 fold) with LOD and LOQ ranged from 0.01 to 0.49 ng mL^-1 and 0.04-1.48 ng mL^-1, respectively. Moreover, we evaluated various diluents to investigate bench top stability (at 4 °C) of targeted analytes in tissue samples during LC-MS assay up to 24 h. Ethanol was determined to be an optimum diluent without any significant oxidation of reduced CoQ up to 24 h. The developed method offers a rapid, highly sensitive and selective strategy for the measurement of redox states of CoQs in clinical studies.

Comparison of Selected Parameters of Redox Homeostasis in Patients with Ataxia-Telangiectasia and Nijmegen Breakage Syndrome

This study compared the antioxidant status and major lipophilic antioxidants in patients with ataxia-telangiectasia (AT) and Nijmegen breakage syndrome (NBS). Total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), and concentrations of coenzyme Q10 (CoQ10) and vitamins A and E were estimated in the plasma of 22 patients with AT, 12 children with NBS, and the healthy controls. In AT patients, TAS (median 261.7 μmol/L) was statistically lower but TOS (496.8 μmol/L) was significantly elevated in comparison with the healthy group (312.7 μmol/L and 311.2 μmol/L, resp.). Tocopherol (0.8 μg/mL) and CoQ10 (0.1 μg/mL) were reduced in AT patients versus control (1.4 μg/mL and 0.3 μg/mL, resp.). NBS patients also displayed statistically lower TAS levels (290.3 μmol/L), while TOS (404.8 μmol/L) was comparable to the controls. We found that in NBS patients retinol concentration (0.1 μg/mL) was highly elevated and CoQ10 (0.1 μg/mL) was significantly lower in comparison with those in the healthy group. Our study confirms disturbances in redox homeostasis in AT and NBS patients and indicates a need for diagnosing oxidative stress in those cases as a potential disease biomarker. Decreased CoQ10 concentration found in NBS and AT indicates a need for possible supplementation.

Low-cost and disposable sensors for the simultaneous determination of coenzyme Q10 and α-lipoic acid using manganese (IV) oxide-modified screen-printed graphene electrodes

In this work, for the first time, manganese (IV) oxide-modified screen-printed graphene electrodes (MnO₂/SPGEs) were developed for the simultaneous electrochemical detection of coenzyme Q10 (CoQ10) and α-lipoic acid (ALA). This sensor exhibits attractive benefits such as simplicity, low production costs, and disposability. Cyclic voltammetry (CV) was used to characterize the electrochemical behavior of the analyte and investigate the capacitance and electroactive surface area of the unmodified and modified electrode surfaces. The electrochemical behavior of CoQ10 and ALA on MnO₂/SPGEs was also discussed. Additionally, square wave anodic stripping voltammetry (SWASV) was used for the quantitative determination of CoQ10 and ALA. Under optimal conditions, the obtained signals are linear in the concentration range from 2.0 to 75.0 μg mL^-1 for CoQ10 and 0.3-25.0 μg mL^-1 for ALA. The low limits of detection (LODs) were found to be 0.56 μg mL^-1 and 0.088 μg mL^-1 for CoQ10 and ALA, respectively. Moreover, we demonstrated the utility and applicability of the MnO₂/SPGE sensor through simultaneous measurements of CoQ10 and ALA in dietary supplements. The sensor provides high accuracy measurements, exhibiting its high potential for practical applications.

Benefits of Curcumin Supplementation on Antioxidant Status in β-Thalassemia Major Patients: A Double-Blind Randomized Controlled Clinical Trial

Background: β-Thalassemia major, the most common inherited anemia in the world, is associated with imbalance in the oxidant-antioxidant system. The objective of this study was to evaluate the efficacy of curcumin supplementation on markers of oxidative stress in patients with β-Thalassemia. Methods: This double-blind randomized controlled clinical trial was performed on 61 β-thalassemia major patients. Subjects in the curcumin group received two 500 mg curcumin capsules daily and patients in the placebo group took 2 placebo capsules daily for 12 weeks. Dietary intakes and biochemical parameters were assessed at the beginning and the end of intervention. Results: At the end of the study, serum malondialdehyde (MDA), total and direct bilirubin significantly decreased (p = 0.002, p < 0.001, and p < 0.001, respectively) and total antioxidant capacity significantly increased (p = 0.005) in the curcumin group. Based on the analysis of covariance, a significant reduction in MDA, total and direct bilirubin was also detected in the curcumin group when compared to the placebo group (p = 0.001, p = 0.039, and p = 0.013, respectively). Changes in hemoglobin, serum iron, ferritin, catalase, and vitamin E were not significant in any of the 2 groups. Conclusions: Curcumin supplementation in combination with deferoxamin improved the antioxidant status in β-thalassemia major patients. Curcumin may be useful for the relief of metabolic complications in these patients.

Data representing two separate LC-MS methods for detection and quantification of water-soluble and fat-soluble vitamins in tears and blood serum

Two separate liquid chromatography (LC)-mass spectrometry (MS) methods were developed for determination and quantification of water-soluble and fat-soluble vitamins in human tear and blood serum samples. The water-soluble vitamin method was originally developed to detect vitamins B₁, B₂, B₃ (nicotinamide), B₅, B₆ (pyridoxine), B₇, B₉ and B₁₂ while the fat-soluble vitamin method detected vitamins A, D₃, 25(OH)D_3, E and K₁. These methods were then validated with tear and blood serum samples. In this data in brief article, we provide details on the two LC-MS methods development, methods sensitivity, as well as precision and accuracy for determination of vitamins in human tears and blood serum. These methods were then used to determine the vitamin concentrations in infant and parent samples under a clinical study which were reported in "Determination of Water-Soluble and Fat-Soluble Vitamins in Tears and Blood Serum of Infants and Parents by Liquid Chromatography/Mass Spectrometry DOI:10.1016/j.exer.2016.12.007 [1]". This article provides more details on comparison of vitamin concentrations in the samples with the ranges reported in the literature along with the medically accepted normal ranges. The details on concentrations below the limits of detection (LOD) and limits of quantification (LOQ) are also discussed. Vitamin concentrations were also compared and cross-correlated with clinical data and nutritional information. Significant differences and strongly correlated data were reported in [1]. This article provides comprehensive details on the data with slight differences or slight correlations.

Coenzyme Q10 and Oxidative Stress: Inflammation Status in Hepatocellular Carcinoma Patients after Surgery

(1) Background: Hepatocellular carcinoma (HCC) is the second leading cause of cancer deaths worldwide, and surgical resection is the main treatment for HCC. To date, no published study has examined the status of coenzyme Q10 in patients with HCC after surgery. Thus, the purpose of this study was to investigate the correlations between the level of coenzyme Q10, oxidative stress, and inflammation in patients with HCC after surgery; (2) Methods: 71 primary HCC patients were recruited. Levels of coenzyme Q10, vitamin E, oxidative stress (malondialdehyde), antioxidant enzymes activity (superoxidase dismutase, catalase, and glutathione peroxidase), and inflammatory markers (high sensitivity C-reactive protein; tumor necrosis factor-α; and interleukin-6) were measured; (3) Results: Patients with HCC had a significantly lower levels of coenzyme Q10 (p = 0.01) and oxidative stress (p < 0.01), and significantly higher levels of antioxidant enzymes activities and inflammation after surgery (p < 0.05). The level of coenzyme Q10 was significantly positively correlated with antioxidant capacity (vitamin E and glutathione peroxidase activity) and negatively correlated with inflammation markers after surgery; (4) Conclusion: Hepatocarcinogenesis is associated with oxidative stress, and coenzyme Q10 may be considered an antioxidant therapy for patients with HCC, particularly those with higher inflammation after surgery.

LC/MS/MS analysis of α-tocopherol and coenzyme Q10 content in lyophilized royal jelly, beebread and drone homogenate

This study shows the results of application liquid chromatography-tandem mass spectrometry (LC/MS/MS) for assay of the content of α-tocopherol and coenzyme Q₁₀ in bee products of animal origin, i.e. royal jelly, beebread and drone homogenate. The biological matrix was removed using extraction with n-hexane. It was found that drone homogenate is a rich source of coenzyme Q₁₀ . It contains only 8 ± 1 µg/g of α-tocopherol and 20 ± 2 µg/g of coenzyme Q₁₀ . The contents of assayed compounds in royal jelly were 16 ± 3 and 8 ± 0.2 µg/g of α-tocopherol and coenzyme Q₁₀ , respectively. Beebread appeared to be the richest of α-tocopherol. Its level was 80 ± 30 µg/g, while the level of coenzyme Q₁₀ was only 11.5 ± 0.3 µg/g. Copyright © 2016 John Wiley & Sons, Ltd.

Effects of coenzyme Q10 supplementation on antioxidant capacity and inflammation in hepatocellular carcinoma patients after surgery: a randomized, placebo-controlled trial

Background

It has been reported that higher levels of oxidative stress and inflammation play a key role in the progression of hepatocellular carcinoma (HCC) after surgery. Coenzyme Q10 is an endogenous lipid-soluble antioxidant. To date, no intervention study has investigated coenzyme Q10 supplementation in HCC patients after surgery. The purpose of this study was to investigate oxidative stress, antioxidant enzymes activity, and inflammation levels in HCC patients after surgery following administration of coenzyme Q10 (300 mg/day).

Methods

This study was designed as a single-blinded, randomized, parallel, placebo-controlled study. Patients who were diagnosed with primary HCC (n = 41) and were randomly assign to a placebo (n = 20) or coenzyme Q10 (300 mg/day, n = 21) group after surgery. The intervention lasted for 12 weeks. Plasma coenzyme Q10, vitamin E, oxidative stress antioxidant enzymes activity and inflammatory markers levels were measured.

Results

The oxidative stress (p = 0.04) and inflammatory markers (hs-CRP and IL-6, p < 0.01) levels were significantly decreased, and the antioxidant enzymes activity was significantly increased (p < 0.01) after 12 weeks of coenzyme Q10 supplementation. In addition, the coenzyme Q10 level was significantly negatively correlated with the oxidative stress (p = 0.01), and positively correlated with antioxidant enzymes activity (SOD, p = 0.01; CAT, p < 0.05; GPx, p = 0.04) and vitamin E level (p = 0.01) after supplementation.

Conclusion

In conclusion, we demonstrated that a dose of 300 mg/d of coenzyme Q10 supplementation significantly increased the antioxidant capacity and reduced the oxidative stress and inflammation levels in HCC patients after surgery.

Trial registration

Clinical Trials.gov Identifier: NCT01964001

Automated statistical experimental design approach for rapid separation of coenzyme Q10 and identification of its biotechnological process related impurities using UHPLC and UHPLC-APCI-MS

A novel ultra high performance liquid chromatography method development strategy was ameliorated by applying quality by design approach. The developed systematic approach was divided into five steps (i) Analytical Target Profile, (ii) Critical Quality Attributes, (iii) Risk Assessments of Critical parameters using design of experiments (screening and optimization phases), (iv) Generation of design space, and (v) Process Capability Analysis (Cp) for robustness study using Monte Carlo simulation. The complete quality-by-design-based method development was made automated and expedited by employing sub-2 μm particles column with an ultra high performance liquid chromatography system. Successful chromatographic separation of the Coenzyme Q10 from its biotechnological process related impurities was achieved on a Waters Acquity phenyl hexyl (100 mm × 2.1 mm, 1.7 μm) column with gradient elution of 10 mM ammonium acetate buffer (pH 4.0) and a mixture of acetonitrile/2-propanol (1:1) as the mobile phase. Through this study, fast and organized method development workflow was developed and robustness of the method was also demonstrated. The method was validated for specificity, linearity, accuracy, precision, and robustness in compliance to the International Conference on Harmonization, Q2 (R1) guidelines. The impurities were identified by atmospheric pressure chemical ionization-mass spectrometry technique. Further, the in silico toxicity of impurities was analyzed using TOPKAT and DEREK software.

Cardiorenal Involvement in Metabolic Syndrome Induced by Cola Drinking in Rats: Proinflammatory Cytokines and Impaired Antioxidative Protection

We report experimental evidence confirming renal histopathology, proinflammatory mediators, and oxidative metabolism induced by cola drinking. Male Wistar rats drank ad libitum regular cola (C, n = 12) or tap water (W, n = 12). Measures. Body weight, nutritional data, plasma glucose, cholesterol fractions, TG, urea, creatinine, coenzyme Q₁₀, SBP, and echocardiograms (0 mo and 6 mo). At 6 months euthanasia was performed. Kidneys were processed for histopathology and immunohistochemistry (semiquantitative). Compared with W, C rats showed (I) overweight (+8%, p < 0.05), hyperglycemia (+11%, p < 0.05), hypertriglyceridemia (2-fold, p < 0.001), higher AIP (2-fold, p < 0.01), and lower Q₁₀ level (−55%, p < 0.05); (II) increased LV diastolic diameter (+9%, p < 0.05) and volume (systolic +24%, p < 0.05), posterior wall thinning (−8%, p < 0.05), and larger cardiac output (+24%, p < 0.05); (III) glomerulosclerosis (+21%, p < 0.05), histopathology (+13%, p < 0.05), higher tubular expression of IL-6 (7-fold, p < 0.001), and TNFα (4-fold, p < 0.001). (IV) Correlations were found for LV dimensions with IL-6 (74%, p < 0.001) and TNFα (52%, p < 0.001) and fully abolished after TG and Q₁₀ control. Chronic cola drinking induced cardiac remodeling associated with increase in proinflammatory cytokines and renal damage. Hypertriglyceridemia and oxidative stress were key factors. Hypertriglyceridemic lipotoxicity in the context of defective antioxidant/anti-inflammatory protection due to low Q₁₀ level might play a key role in cardiorenal disorder induced by chronic cola drinking in rats.

Vitamin E Improves Serum Paraoxonase-1 Activity and Some Metabolic Factors in Patients with Type 2 Diabetes: No Effects on Nitrite/Nitrate Levels

OBJECTIVE

It is known that markers of oxidative stress and nitrite/nitrate anion (NO_x) increase and activity of antioxidative enzyme paraoxonase-1 decline in type 2 diabetes mellitus (DM). The effects of vitamin E on paraoxonase-1 activity and NO_x in patients with type 2 diabetes are not known. The purpose of this study was to examine the hypothesis that vitamin E supplementation would affect paraoxonase-1 activity, metabolic factors, and NO_x in patients with DM.

METHODS

This double-blind, randomized, controlled clinical trial was conducted on 83 patients with DM aged 30-60 years. Forty-two of the subjects had taken 400 IU/day vitamin E and 41 were given placebo over 8 weeks. Fasting blood samples, anthropometric measurements, and dietary intake data were collected at the baseline and at the end of the trial.

RESULTS

Vitamin E significantly increased serum vitamin E level, paraoxonase-1 activity, and total antioxidant status (TAS) and decreased fasting blood sugar (FBS) compared to the control group (p < 0.05). Hemoglobin A1c, serum insulin, and insulin resistance significantly decreased in the vitamin E group compared to baseline values (p < 0.05). Alterations in serum levels of malondialdehyde and NO_x were not significant in any of groups (p > 0.05).

CONCLUSIONS

Vitamin E improved serum vitamin E level, paraoxonase-1 activity, TAS, and FBS in patients with type 2 diabetes. Longitudinal studies are warranted to assess the outcome of these results in reducing complications of diabetes in patients with type 2 diabetes.

The ratio of oxidized and reduced forms of selected antioxidants as a possible marker of oxidative stress in humans

Oxidative stress is an imbalance between reactive oxygen species exposure and the ability of organisms to detoxify the reactive intermediates and to repair the oxidative damage of biologically important molecules. Many clinical studies of oxidative stress unfortunately provide conflicting and contradictory results. The ability of antioxidant systems to adequately respond to oxidative stress can be used in laboratory diagnostics. In the present review, methods using the ratio of reduced and oxidized forms of uric acid, ascorbic acid, glutathione and coenzyme Q10 as suitable indicators of oxidative stress are discussed. From the mentioned publications it is evident that suitable sample preparation prior to analysis is crucial.

New analytical strategies applied to the determination of Coenzyme Q10 in biological matrix

In the last few years the importance of Coenzyme Q10 (CoQ10) determination has gained clinical relevance. CoQ10 is a redox-active, lipophilic substance integrated in the mitochondrial respiratory chain which acts as an electron carrier for the production of cellular energy. In addition, it is recognized as a primary regenerating antioxidant playing an intrinsic role against oxidative damage. There are some reports of low CoQ10 levels in a number of disorders, such as cancer, muscular, neurodegenerative, cardiological, and reproductive diseases. Therefore, it is a priority to develop analytical methodologies for evaluating CoQ10 in matrices of greater importance for the correct diagnosis of diseases, simple enough to be used in routine clinical laboratories. In this chapter two recently developed techniques, capillary electrophoresis and microHPLC, for the analysis of CoQ10 in biological matrices, are studied.

Functional and morphological changes in endocrine pancreas following cola drink consumption in rats

Aim

We report the effects of long-term cola beverage drinking on glucose homeostasis, endocrine pancreas function and morphology in rats.

Methods

Wistar rats drank: water (group W), regular cola beverage (group C, sucrose sweetened) or “light” cola beverage (group L, artificially sweetened). After 6 months, 50% of the animals in each group were euthanized and the remaining animals consumed water for the next 6 months when euthanasia was performed. Biochemical assays, insulinemia determination, estimation of insulin resistance (HOMA-IR), morphometry and immunohistochemistry evaluations were performed in pancreas.

Results

Hyperglycemia (16%, p<0.05), CoQ₁₀ (coenzyme-Q₁₀) decrease (−52%,p<0.01), strong hypertriglyceridemia (2.8-fold, p<0.01), hyperinsulinemia (2.4 fold, p<0.005) and HOMA-IR increase (2.7 fold, p<0.01) were observed in C. Group C showed a decrease in number of α cells (−42%, p<0.01) and β cells (−58%, p<0.001) and a moderate increase in α cells’ size after wash-out (+14%, p<0.001). Group L showed reduction in β cells’ size (−9%, p<0.001) and only after wash-out (L₁₂) a 19% increase in size (p<0.0001) with 35% decrease in number of α cells (p<0.01). Groups C and L showed increase in α/β-cell ratio which was irreversible only in C (α/β = +38% in C₆,+30% in C₁₂, p<0.001vs.W₆). Regular cola induced a striking increase in the cytoplasmic expression of Trx1 (Thioredoxin-1) (2.25-fold in C₆ vs. W₆; 2.7-fold in C₁₂ vs. W_12, p<0.0001) and Prx2 (Peroxiredoxin-2) (3-fold in C₆ vs. W₆; 2-fold in C₁₂ vs. W_12, p<0.0001). Light cola induced increase in Trx1 (3-fold) and Prx2 (2-fold) after wash-out (p<0.0001, L₁₂ vs. W₁₂).

Conclusion

Glucotoxicity may contribute to the loss of β cell function with depletion of insulin content. Oxidative stress, suggested by increased expression of thioredoxins and low circulating levels of CoQ₁₀, may follow sustained hyperglycemia. A likely similar panorama may result from the effects of artificially sweetened cola though via other downstream routes.

The effects of Juglans regia L. (walnut) extract on certain biochemical paramaters and in the prevention of tissue damage in brain, kidney, and liver in CCl4 applied Wistar rats

Objective: The purpose of this study is to demonstrate protective effects of walnut samples on CCl

Methods: Walnut fruits were extracted and then subjected to vitamin and flavonoid analyses. The extracts obtained were injected intraperitoneally every other day to Wistar male rats given carbon tetrachloride (CCl

Results: Given the results achieved, it was found that the levels of fatty acids increased in the brain and kidney tissues after CCl

Conclusion: Our data indicates that walnut extract has protective effects against LPO formation in the brain, kidney and liver tissues.

Fast, simple, and sensitive high-performance liquid chromatography method for measuring vitamins A and E in human blood plasma

Vitamins A and E are fat-soluble vitamins that play important roles in several physiological processes. Monitoring their concentrations is needed to detect deficiency and guide therapy. In this study, we developed a high-performance liquid chromatography method to measure the major forms of vitamin A (retinol) and vitamin E (α-tocopherol and γ-tocopherol) in human blood plasma. Vitamins A and E were extracted with hexane and separated on a reversed-phase column using methanol as the mobile phase. Retinol was detected by ultraviolet absorption, whereas tocopherols were detected by fluorescence emission. The chromatographic cycle time was 4.0 min per sample. The analytical measurement range was 0.03-5.14, 0.32-36.02, and 0.10-9.99 mg/L for retinol, α-tocopherol, and γ-tocopherol, respectively. Intr-aassay and total coefficient of variation were <6.0% for all compounds. This method was traceable to standard reference materials offered by the National Institute of Standards and Technology. Reference intervals were established using plasma samples collected from 51 healthy adult donors and were found to be 0.30-1.20, 6.0-23.0, and 0.3-3.2 mg/L for retinol, α-tocopherol, and γ-tocopherol, respectively. In conclusion, we developed and validated a fast, simple, and sensitive high-performance liquid chromatography method for measuring the major forms of vitamins A and E in human plasma.

Determination of a method for extraction of coenzyme Q10 in human plasma: optimization of the use of surfactants and other variables

OBJECTIVE

To establish a routine for the extraction of the total levels of CoQ10 in human plasma through the Ultra High Performance Liquid Chromatography (UHPLC).

METHODS

Two extraction protocols were tested: a) methanol: hexane and b) 1-propanol. The following parameters were analyzed: extraction temperature (19ºC and 4ºC), extraction tubes (glass and polypropylene), and surfactants (SDS, Triton X-100, Tween-20) at different concentrations, i.e., 1%, 3%, 5% and 10%.

RESULTS

The results showed that the method of extraction of CoQ10 in a sample of human plasma at 4ºC, using solvents methanol: hexane (85:15, v/v) in the presence of surfactant Tween-20 at 3% and polypropylene tubes showed better efficiency and reproducibility when compared to the method with 1-propanol.

CONCLUSION

By the analyses performed, it was possible to observe that the addition of the surfactant Tween-20 promoted an increase in the recovery of CoQ10 by the methanol:hexane extraction method. This method showed good reproducibility, with a low coefficient of variation and high sensitivity, since CoQ10 was detected in samples of plasma of a control individual using a UV-type detector. The use of UHPLC equipment allowed a total analysis with total run time of 3.5 minutes, enabling the rapid achievement of results, considered mandatory for laboratory routines.

Effects of coenzyme Q10 supplementation (300 mg/day) on antioxidation and anti-inflammation in coronary artery disease patients during statins therapy: a randomized, placebo-controlled trial

Background

High oxidative stress and chronic inflammation can contribute to the pathogenesis of coronary artery disease (CAD). Coenzyme Q10 is an endogenous lipid-soluble antioxidant. Statins therapy can reduce the biosynthesis of coenzyme Q10. The purpose of this study was to investigate the effects of a coenzyme Q10 supplement (300 mg/d; 150 mg/b.i.d) on antioxidation and anti-inflammation in patients who have CAD during statins therapy.

Methods

Patients who were identified by cardiac catheterization as having at least 50% stenosis of one major coronary artery and who were treated with statins for at least one month were enrolled in this study. The subjects (n = 51) were randomly assigned to the placebo (n = 24) and coenzyme Q10 groups (Q10-300 group, n = 27). The intervention was administered for 12 weeks. The concentrations of coenzyme Q10, vitamin E, antioxidant enzymes activities (superoxide dismutase, catalase, and glutathione peroxidase), and inflammatory markers [C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6)] were measured in the 42 subjects (placebo, n = 19; Q10-300, n = 23) who completed the study.

Results

The levels of the plasma coenzyme Q10 (P < 0.001) and antioxidant enzymes activities (P < 0.05) were significantly higher after coenzyme Q10 supplementation. The levels of inflammatory markers (TNF-α, P = 0.039) were significantly lower after coenzyme Q10 supplementation. The subjects in the Q10-300 group had significantly higher vitamin E (P = 0.043) and the antioxidant enzymes activities (P < 0.05) than the placebo group at week 12. The level of plasma coenzyme Q10 was significantly positively correlated with vitamin E (P = 0.008) and antioxidant enzymes activities (P < 0.05) and was negatively correlated with TNF-α (P = 0.034) and IL-6 (P = 0.027) after coenzyme Q10 supplementation.

Conclusion

Coenzyme Q10 supplementation at 300 mg/d significantly enhances antioxidant enzymes activities and lowers inflammation in patients who have CAD during statins therapy.

Trial registration

Clinical Trials.gov Identifier: NCT01424761.

Analysis of circulating lipid-phase micronutrients in humans by HPLC: review and overview of new developments

Retinol, tocopherols, coenzyme Q10, carotenoids, and vitamin D are lipophilic compounds shown to function as important health-protective agents by mitigating the damaging effects of oxidative and other injury. Scientific interest in evaluating these compounds has resurfaced in recent years, particularly in the nutritional, clinical and epidemiologic fields, and has precipitated the development of a multitude of new analytical techniques. This review considers recent developments in HPLC-based assays since 2007 for the simultaneous determination of these lipid-phase compounds utilizing exclusively serum or plasma as these matrices are mostly used in clinical and epidemiological investigations. We also provide an overview of blood measurements for selected carotenoids, tocopherols, coenzyme Q10 and retinol from the last 15years of healthy umbilical cord blood, children, and adults.

Encapsulation of coenzyme Q10 in a simple emulsion-based nutraceutical formulation and application in cheese manufacturing

Coenzyme Q10 (CoQ10) was encapsulated successfully in a nutraceutical formulation composed of calcium caseinate, flaxseed oil and lecithin. The effect of CoQ10 on the physico-chemical stability of emulsions was compared to emulsions without CoQ10. According to ATR-FTIR analysis, emulsions were found to be more stable in the presence of CoQ10. The emulsion with CoQ10 was used as a functional cream in the cheese making process. The retention rate of CoQ10, composition and cheese yield were also determined. Quantification of CoQ10 by HPLC showed that the retention of this lipophilic agent into cheese matrix was 93% and equivalent to the total lipid retention. Protein retention and cheese yield were not affected by the addition of the functional cream. For the first time, CoQ10 has been encapsulated in a cheese matrix, hence demonstrating that CoQ10 could be used in the development of functional cheeses.

Analytical problems with the determination of coenzyme Q10 in biological samples

The article discusses analytical problems related to the determination of coenzyme Q10 in biological samples. The assaying of coenzyme Q10 in complex samples, such as plasma, tissues, or food items requires meticulous sample preparation prior to final quantification. The process typically consists of the following steps: deproteinization, extraction, and ultimately reduction of extract volumes. At times drying under a gentle stream of neutral gas is applied. In the case of solid samples, a careful homogenization is also required. Each step of the sample preparation process can be a source of analytical errors that may lead to inaccurate results. The main aim of this work is to point to sources of analytical errors in the preparation process and their relation to physicochemical properties of coenzyme Q10. The article also discusses ways of avoiding and reducing the errors.

Application of core-shell technology for determination of retinol and alpha-tocopherol in breast milk

Breast milk is a main source of fat-soluble vitamins for newborns and it is needful to monitor the nutritional status prior to its application. In this work a novel, high-throughput and low-cost method for monitoring of retinol and alpha-tocopherol in breast milk was developed, validated and compared with reference method using monolithic column. For this purpose five various porous shell and monolithic columns were tested on the basis of relationship between HETP and linear mobile phase velocity, analysis time and consumption of solvents. Finally the core-shell analytical column Kinetex C18 (2.6 μm, 100 Å, 100×4.6 mm) was chosen as the best and optimal values of flow rate, injection volume and temperature of analysis were established. The detection of retinol and alpha-tocopherol was carried out at 325 and 295 nm, respectively by diode array detector. The LOD 0.004 μmol/L and 0.078 μmol/L, the LOQ 0.012 μmol/L and 0.182 μmol/L for retinol and alpha-tocopherol, respectively were calculated. The validation data showed good linearity, repeatability of retention time with RSD 0.22% and 0.12%, repeatability of peak area with RSD 6.94% and 1.75%, recovery 114.1-116.3% and 99.0-108.6% for retinol and alpha-tocopherol, respectively. Moreover, the newly developed method substantially decreased the solvent consumption by about 263 mL per 100 samples with the total time of analysis 1.75 min in comparison with analysis time 1.80 of the reference method.

A comparative evaluation of coenzyme Q10-loaded liposomes and solid lipid nanoparticles as dermal antioxidant carriers

Background

The effective delivery of coenzyme Q10 (Q10) to the skin has several benefits in therapy for different skin pathologies. However, the delivery of Q10 to deeper layers of skin is challenging due to low aqueous solubility of Q10. Liposomes and solid lipid nanoparticles (SLN) have many advantages to accomplish the requirements in topical drug delivery. This study aims to evaluate the influence of these nanosystems on the effective delivery of Q10 into the skin.

Methods

Q10-loaded liposomes (LIPO-Q10) and SLNs (SLN-Q10) were prepared by thin film hydration and high shear homogenization methods, respectively. Particle size (PS), polydispersity index (PI), zeta potential (ZP), and drug entrapment efficiency were determined. Differential scanning calorimetry analysis and morphological transmission electron microscopy (TEM) examination were conducted. Biocompatibility/cytotoxicity studies of Q10-loaded nanosystems were performed by means of cell culture (human fibroblasts) under oxidative conditions. The protective effect of formulations against production of reactive oxygen species were comparatively evaluated by cytofluorometry studies.

Results

PS of uniform SLN-Q10 and LIPO-Q10 were determined as 152.4 ± 7.9 nm and 301.1 ± 8.2 nm, respectively. ZPs were −13.67 ± 1.32 mV and −36.6 ± 0.85 mV in the same order. The drug entrapment efficiency was 15% higher in SLN systems. TEM studies confirmed the colloidal size. SLN-Q10 and LIPO-Q10 showed biocompatibility towards fibroblasts up to 50 μM of Q10, which was determined as suitable for cell proliferation. The mean fluorescence intensity % depending on ROS production determined in cytofluorometric studies could be listed as Q10 ≥ SLN-Q10 > LIPO-Q10.

Conclusion

The LIPO-Q10 system was able to enhance cell proliferation. On the contrary, SLN-Q10 did not show protective effects against ROS accumulation. As a conclusion, liposomes seem to have advantages over SLN in terms of effective delivery of Q10 to skin for antioxidant purposes.