Bioequivalence of two omega-3 fatty acid ethyl ester formulations: a case of clinical pharmacology of dietary supplements

Soft-capsule formulation of a re-esterified triglyceride omega-3 employing self-emulsifying technology and bioavailability evaluation in healthy volunteers

Despite the superior clinical efficacy of the re-esterified triglyceride (rTG) form compared to the ethylester form, few studies have been conducted on improving the bioavailability of the rTG form of omega-3 oil. The aim of study was to evaluate the effect of self emulsifying formulation on the improvement of bioavailability of rTG form of omega-3 oil. To develop a re-esterified triglyceride (rTG) soft capsule, an rTG-loaded self-emulsifying delivery system (SEDS) was designed using coconut oil, polysorbate 80, and lecithin. Candidate formulations were designed from a phase-diagram study and optimal SEDS formulations containing 85% of high omega-3 (ω-3) oils were screened from the evaluation of droplet size distribution, measurement of oil floating area and emulsion turbidity. The selected, optimized rTG SEDS formulation was filled into a soft capsule (NOVASEDS) and applied to a sequence-randomized, double-blind, single-dose, and two-way crossover clinical study (n = 44), and the the bioavailability of NOVASEDS was compared with that of a 'raw' rTG capsule (rTG OMEGA3) as control. The droplet size (D50) formed from the candidate formulations was approximately 30-45 μm, and the optimal formulation showed a unimodal particle distribution with the smallest oil floating area and small changes in turbidity after 24 h. Cmax and AUC from 0 to 24 h for NOVASEDS, calculated from docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and as the sum of DHA and EPA, were significantly higher (P < 0.05) than corresponding values for rTG OMEGA3. In conclusion, NOVASEDS formulated by SEDS technology enabled the manufacture of a high rTG payload soft capsule with improved bioavailability in human subjects.

Comparison of pharmacokinetics of omega-3 fatty acid supplements in monoacylglycerol or ethyl ester in humans: a randomized controlled trial

Background

A diet low in omega-3 fatty acids (n-3 FA) results in low plasma concentrations of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), the two main long chain n-3 FA. n-3 FA supplements on the market are esterified in triglycerides (TG) or ethyl ester (EE); the latter is absorbed less than other esterification forms. The objective of this study was to test and compare the pharmacokinetics of n-3 FA esterified in monoacylglycerides (MAG), a predigested form, with the EE form.

Methods

This study was a randomized, double-blind, crossover, controlled, clinical trial. Ten men and ten women between 18 and 60 years old were recruited. Participants received a single oral dose of 3 g of n-3 FA esterified in EE or MAG. Eleven blood samples were collected over 24 h post-dose. Plasma total lipids were extracted, methylated, and analyzed using gas chromatography.

Results

After receiving the MAG form, plasma EPA and DHA peaked at a concentration 3 and 2.5 times higher, respectively, than with the EE form. When provided in MAG form, n-3 FA plasma concentration during the absorption phase was on average 3–5 times higher than in EE form. When n-3 FAs were provided esterified in MAG, their concentration 24 h post-dose was higher than in EE. Males had a lower n-3 FA plasma concentration than females when n-3 FAs were provided in EE but there was no sexe difference when provided in MAG.

Conclusions

Plasma concentration of DHA and EPA was higher when provided in MAG than EE form.

A Validation and Estimation of Total Eicosapentaenoic and Docosahexaenoic acids Using LC-MS/MS with Rapid Hydrolysis Enzymatic Method for Hydrolysis of Omega Lipids in Human Plasma and its Application in the Pharmacokinetic Study

Background:

In this study, we have developed a novel, rapid enzymatic hydrolysis method for conversion of omega lipids (omega fatty acid triglycerides, phospholipids, omega conjugates) in to free fatty acids at room temperature using lipase and esterase enzymes. </P><P> Objective: To develop simple enzymatic hydrolysis and rapid sample extraction method for quantification of free (un-esterified) and conjugated (esterified) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) to provide the total EPA and DHA lipids present in human plasma. Quantification of total EPA/DHA was performed using liquid chromatography and tandem mass spectrometer instrument.

Methods:

The plasma sample is digested with lipase and esterase enzymes and extracted by using combined precipitation and liquid-liquid techniques. The LC-MS/MS method was optimized using EPA-D5 and DHA-D5 as labeled internal standards for EPA/DHA respectively. The analytical method is validated, utilized for simultaneous quantification of total EPA and DHA lipids in plasma collected from healthy human volunteers clinical study.

Results:

The reproducibility of the established enzymatic hydrolysis method was demonstrated by incurred sample reanalysis and the results for total EPA and DHA lipid were 93.33% and 96.67% respectively. The pharmacokinetic and statistical analysis was performed using baseline corrected concentration of total EPA and DHA lipids.

Conclusion:

The enzymatic hydrolysis method for conversion of omega fatty acid triglycerides, phospholipids, omega conjugates in to free fatty acid was reported first time for the quantitative application. The shorter time for sample workup procedure, simple enzymatic hydrolysis at room temperature and 3 minutes chromatography run time are well suitable for bioavailability/ bioequivalence studies.

A novel liquid chromatography/tandem mass spectrometry (LC-MS/MS) based bioanalytical method for quantification of ethyl esters of Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA) and its application in pharmacokinetic study

Omega-3 fatty acids are clinically useful and the two marine omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are prevalent in fish and fish oils. Omega-3 fatty acid formulations should undergo a rigorous regulatory step in order to obtain United States Food and Drug Administration (USFDA) approval as prescription drug. In connection with that, despite quantifying EPA and DHA fatty acids, there is a need for quantifying the level of ethyl esters of them in biological samples. In this study, we make use of reverse phase high performance liquid chromatography coupled with mass spectrometry (RP-HPLC-MS)technique for the method development. Here, we have developed a novel multiple reaction monitoring method along with optimized parameters for quantification of EPA and DHA as ethyl esters. Additionally, we attempted to validate the bio-analytical method by conducting the sensitivity, selectivity, precision accuracy batch, carryover test and matrix stability experiments. Furthermore, we also implemented our validated method for evaluation of pharmacokinetics of omega fatty acid ethyl ester formulations.

Determination of Eicosapentaenoic, Docosahexaenoic, and Arachidonic Acids in Human Plasma by High-Performance Liquid Chromatography with Electrochemical Detection

A high-performance liquid chromatography with electrochemical detection (HPLC-ECD) system was developed for the simultaneous determination of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid (AA) in human plasma. In the present HPLC-ECD system, EPA, DHA, and AA were separated using a reverse-phase C30 column and detected based on the voltammetric reduction of 3,5-di-tert-butyl-1,2-benzoquinone (DBBQ). Chromatographic peak areas were proportional to the concentration of EPA, DHA, and AA from 0.75 μM to 0.1 mM (r > 0.998). The concentrations of EPA, DHA, and AA in plasma from healthy human subjects after overnight fasting were determined, and the ratio of EPA to AA was obtained by the present HPLC-ECD method, which required 40 μL of human plasma and a simple procedure of sample preparation using diethyl ether extraction. Moreover, changes in EPA, DHA, and AA concentrations in a human subject were monitored before and after fish oil supplement administration by the present HPLC-ECD system.

Anti-inflammatory effects of docosahexaenoic acid: Implications for its cancer chemopreventive potential

The implication of inflammatory tissue damage in pathophysiology of human cancer as well as some metabolic disorders has been under intense investigation. Numerous studies have identified a series of critical signaling molecules involved in cellular responses to inflammatory stimuli. These include nuclear factor κB, peroxisome proliferator-activated receptor γ, nuclear factor erythroid 2 p45-related factor 2 and sterol regulatory element-binding protein 1. The proper regulation of these transcription factors mediating pro- and anti-inflammatory signaling hence provides an important strategy for the chemoprevention of inflammation-associated cancer. There is compelling evidence supporting that dietary supplementation with fish oil-derived ω-3 polyunsaturated fatty acids including docosahexaenoic acid (DHA) ameliorates symptomatic inflammation associated with cancer as well as other divergent human disorders. Acute or physiologic inflammation is an essential body's first line of defence to microbial infection and tissue injuries, but it must be properly completed by a process termed 'resolution'. Failure of resolution mechanisms can result in persistence of inflammation, leading to chronic inflammatory conditions and related malignancies. The phagocytic engulfment of apoptotic neutrophils and clearance of their potentially histotoxic contents by macrophages, called efferocytosis is an essential component in resolving inflammation. Of note, DHA is a precursor of endogenous proresolving lipid mediators which regulate the leukocyte trafficking and recruitment and thereby facilitate efferocytosis. Therefore, DHA and its metabolites may have a preventive potential in the management of human cancer which arises as a consequence of impaired resolution of inflammation as well as chronic inflammation.

Biomarkers for nutrient intake with focus on alternative sampling techniques

Biomarkers of nutrient intake or nutrient status are important objective measures of foods/nutrients as one of the most important environmental factors people are exposed to. It is very difficult to obtain accurate data on individual food intake, and there is a large variation of nutrient composition of foods consumed in a population. Thus, it is difficult to obtain precise measures of exposure to different nutrients and thereby be able to understand the relationship between diet, health, and disease. This is the background for investing considerable resources in studying biomarkers of nutrients believed to be important in our foods. Modern technology with high sensitivity and specificity concerning many nutrient biomarkers has allowed an interesting development with analyses of very small amounts of blood or tissue material. In combination with non-professional collection of blood by finger-pricking and collection on filters or sticks, this may make collection of samples and analyses of biomarkers much more available for scientists as well as health professionals and even lay people in particular in relation to the marked trend of self-monitoring of body functions linked to mobile phone technology. Assuming standard operating procedures are used for collection, drying, transport, extraction, and analysis of samples, it turns out that many analytes of nutritional interest can be measured like metabolites, drugs, lipids, vitamins, minerals, and many types of peptides and proteins. The advantage of this alternative sampling technology is that non-professionals can collect, dry, and mail the samples; the samples can often be stored under room temperature in a dry atmosphere, requiring small amounts of blood. Another promising area is the potential relation between the microbiome and biomarkers that may be measured in feces as well as in blood.

The free fractions of circulating docosahexaenoic acid and eicosapentenoic acid as optimal end-point of measure in bioavailability studies on n-3 fatty acids

The high complexity of n-3 fatty acids absorption process, along with the huge amount of endogenous fraction, makes bioavailability studies with these agents very challenging and deserving special consideration. In this paper we report the results of a bioequivalence study between a new formulation of EPA+DHA ethyl esters developed by IBSA Institut Biochimique and reference medicinal product present on the Italian market. Bioequivalence was demonstrated according to the criteria established by the EMA Guideline on the Investigation of Bioequivalence. We found that the free fractions represent a better and more sensitive end-point for bioequivalence investigations on n-3 fatty acids, since: (i) the overall and intra-subject variability of PK parameters was markedly lower compared to the same variability calculated on the total DHA and EPA fractions; (ii) the absorption process was completed within 4h, and the whole PK profile could be drawn within 12-15 h from drug administration.

Dietary omega-3 polyunsaturated fatty acids alter the fatty acid composition of hepatic and plasma bioactive lipids in C57BL/6 mice: a lipidomic approach

Background

Omega (n)-3 polyunsaturated fatty acids (PUFA) are converted to bioactive lipid components that are important mediators in metabolic and physiological pathways; however, which bioactive compounds are metabolically active, and their mechanisms of action are still not clear. We investigated using lipidomic techniques, the effects of diets high in n-3 PUFA on the fatty acid composition of various bioactive lipids in plasma and liver.

Methodology and Principal Findings

Female C57BL/6 mice were fed semi-purified diets (20% w/w fat) containing varying amounts of n-3 PUFA before mating, during gestation and lactation, and until weaning. Male offspring were continued on their mothers’ diets for 16 weeks. Hepatic and plasma lipids were extracted in the presence of non-naturally occurring internal standards, and tandem electrospray ionization mass spectrometry methods were used to measure the fatty acyl compositions. There was no significant difference in total concentrations of phospholipids in both groups. However, there was a significantly higher concentration of eicosapentaenoic acid containing phosphatidylcholine (PC), lysophosphatidylcholine (LPC), and cholesteryl esters (CE) (p < 0.01) in the high n-3 PUFA group compared to the low n-3 PUFA group in both liver and plasma. Plasma and liver from the high n-3 PUFA group also had a higher concentration of free n-3 PUFA (p < 0.05). There were no significant differences in plasma concentrations of different fatty acyl species of phosphatidylethanolamine, triglycerides, sphingomyelin and ceramides.

Conclusions/Significance

Our findings reveal for the first time that a diet high in n-3 PUFA caused enrichment of n-3 PUFA in PC, LPC, CE and free fatty acids in the plasma and liver of C57BL/6 mice. PC, LPC, and unesterified free n-3 PUFA are important bioactive lipids, thus altering their fatty acyl composition will have important metabolic and physiological roles.

Nutritional properties of dietary omega-3-enriched phospholipids

Dietary fatty acids regulate several physiological functions. However, to exert their properties, they have to be present in the diet in an optimal balance. Particular attention has been focused on tissue highly polyunsaturated fatty acids (HPUFAs) n-6/n-3 ratio, influenced by the type and the esterified form of dietary fatty acids. Dietary EPA and DHA when esterified to phospholipids (PLs) are more efficiently incorporated into tissue PLs and seem to possess peculiar properties through specific mechanism(s) of action, such as the capacity to affect endocannabinoid biosynthesis at much lower doses than EPA and DHA in triglyceride form, probably because of the above mentioned higher incorporation into tissue PLs. Downregulation of the endocannabinoid system seems to mediate the positive effects exerted by omega-3-enriched PLs on several parameters of metabolic syndrome. PLs are one of the major dietary forms of EPA and DHA we are exposed to with the everyday diet; therefore, it is not surprising that it guarantees an effective EPA and DHA nutritional activity. Future studies should address whether EPA and DHA in PL form are also more effective than other formulations in ameliorating other pathological conditions where n-3 HPUFAs seem to exert beneficial activities such as cancer and psychiatric disorders.