Design of Novel Tricaprylin-Incorporated Multi-Layered Liposomal System for Skin Delivery of Ascorbic Acid with Improved Chemical Stability.

L-ascorbic acid (Vit C) possesses a variety of dermatological functions in maintaining skin health and anti-aging properties. However, its topical application is challenging owing to its liability to light, oxygen, or heat. Therefore, in this study, a novel liposomal system, including a lipophilic neutral oil named a lipo-oil-some (LOS), was designed to improve the chemical stability and aid the skin absorption of Vit C. The vesicular systems were prepared using the ethanol injection method, employing phosphatidylcholine, cholesterol, dipalmitoyl-sn-glycerol-3-phosphoglycerol, and tricaprylin as neutral oil. The optimized LOS was characterized as follows: shape, multi-layered sphere; size, 981 nm; zeta potential, -58 mV; and Vit C encapsulation efficiency, 35%. The encapsulation of the labile compound into the novel system markedly enhanced photostability, providing over 10% higher Vit C remaining compared to Vit C solution or Vit C-loaded conventional liposome under a light intensity of 20,000 lx. On the other hand, the ex vivo skin permeation and accumulation of Vit C with the LOS system were comparable to those of smaller conventional liposomes (198 nm) in a Franz diffusion cell model mounted with porcine skin. Based on these findings, we concluded that the novel liposomal system could be utilized for skin delivery of Vit C with enhanced chemical stability.

Potencial quimiopreventivo de lipídios estruturados obtidos da Tributirina e Tricaprilina na fase de promoção da hepatocarcinogênese experimental / Chemopreventive potential of structured lipids obtained from Tributyrin and Tricaprylin in the promotion phase of experimental hepatocarcinogenesis

A quimioprevenção do câncer refere-se ao uso de compostos naturais ou sintéticos para prevenir o desenvolvimento das neoplasias antes do estabelecimento da malignidade. O ácido butirico (AB) atua como um potente quimiopreventivo na hepatocarcinogênese, reduzindo o número e o tamanho de lesões pré neoplásicas persistentes (pLPN), induzindo a apoptose e modulando mecanismos epigenéticos. Já o ácido caprílico (AC), além da sua atuação como potencializador de absorção, vem sendo investigado na área da prevenção do câncer. Neste cenário, o objetivo do trabalho visa avaliar a atividade quimiopreventiva de lipídios estruturados (EST) obtidos por interesterificação enzimática da tributirina com a tricaprilina, na fase de promoção da hepatocarcinogênese experimental. Após o processo de interesterificação, o produto final apresentou novos triacilgliceróis com composição de duas moléculas de ácido butírico para uma de ácido caprilíco. Ratos machos isogênicos da linhagem Fischer 344 foram submetidos ao modelo do hepatócito resistente, sendo distribuídos em dois grupos e tratados diariamente por via intragástrica com lipídios estruturados (EST) ou com o seu controle isocalórico, a maltodextrina (MD), durante a fase de promoção. Como esperado, não houve diferença estatística (p>0,05) em relação ao peso inicial e final dos animais dos grupos MD e EST, o que indica ausência de toxicidade dos compostos administrados. Na análise macroscópica do fígado, foi observada uma redução de 33,3% no grupo EST em relação ao número médio de nódulos macroscópicos em comparação ao grupo MD, porém essa redução não atingiu diferença estatística (p>0,05). Para a avaliação das lesões pré neoplásicas (LPN) foi utilizada a marcação imunoistoquímica para glutationa-S-transferase (GST-P). O grupo EST apresentou uma redução no número de lesões em remodelação e total GSTP-P+, quando comparado com o grupo MD (p<0,05). Quando avaliada a % de corpúsculos apoptóticos e índice de proliferação celular, não houve diferença estatística entre os grupos (p>0,05). Animais tratados com lipídios estruturados apresentaram maiores (p<0,05) concentrações de AC e AB por grama de tecido hepático em relação ao tratamento com maltodextrina. Em relação aos danos no DNA, o grupo EST resultou em cometas de comprimentos menores (p<0,05), menores níveis de γ-H2AX (p<0,05) e maiores concentrações de p53 nuclear, quando comparados aos animais que receberam maltodextrina, sugerindo uma proteção contra danos no DNA no grupo tratado com EST. Os resultados mostraram que o tratamento com EST resultou em ações efetivas na fase de promoção da hepatocarcinogênese experimental

Cancer chemoprevention refers to the use of natural or synthetic compounds to prevent the development of neoplasms before the establishment of malignancy. Butyric acid (AB) acts as a potent chemopreventive in hepatocarcinogenesis, reducing the number and size of persistent preneoplastic lesions (pLPN), inducing apoptosis and modulating epigenetic mechanisms. Caprylic acid (CA), in addition to its role as an absorption enhancer, has been investigated in the area of cancer prevention. In this scenario, the objective of this work was to evaluate the chemopreventive activity of structured lipids (EST) obtained by enzymatic interesterification of tributyrin with tricaprylin, in the phase of promotion experimental hepatocarcinogenesis. After the interesterification process, the final product presented new triacylglycerols with a composition of two molecules of butyric acid to one of caprylic acid. Isogenic male Fischer 344 rats were submitted to the resistant hepatocyte model, divided into two groups and treated daily intragastrically with structured lipids (EST) or with its isocaloric control, maltodextrin (MD), during the promotion phase. As expected, there was no statistical difference (p>0.05) in relation to the initial and final weight of the animals in the MD and EST groups, which indicates the absence of toxicity of the administered compounds. In the macroscopic analysis of the liver, a reduction of 33.3% was observed in the EST group in relation to the mean number of macroscopic nodules compared to the MD group, but this reduction did not reach a statistical difference (p>0.05). For the evaluation of pre-neoplastic lesions (PNL) immunohistochemical staining for glutathione-Stransferase (GST-P) was used. The EST group showed a reduction in the number of remodeling lesions and total GSTP-P+, when compared to the MD group (p<0.05). Animals treated with structured lipids had higher (p<0.05) concentrations of AC and AB per gram of liver tissue compared to treatment with maltodextrin. Regarding DNA damage, the EST group resulted in comets of shorter lengths (p<0.05), lower levels of γ-H2AX (p<0.05) and high concentration of nuclear p53, when compared to animals that received maltodextrin, suggesting protection against DNA damage in the EST treated group. The results showed that EST treatment resulted in effective actions in the promotion phase of experimental hepatocarcinogenesis

Understanding the beneficial effect of using medium chain triglycerides in preparation of traditional puran poli.

In the present research work, medium-chain triglyceride (MCT) is used in the preparation of puran poli. Effect of MCT on various attributes likes textural, microbiological, sensory and oxidative stability of puran poli was studied. Use of MCT showed a positive effect on the texture of puran poli without use of hydrocolloids. Texture of puran poli became soft after storage of 15 and 25 days at 25 ± 2 °C and 4 ± 2 °C respectively. Puran poli showed no bacterial growth at both the storage conditions, however, there was yeast and mould growth on Puran poli stored at 25 ± 2 °C after 25 days i.e., 3 × 101 CFU/gm sample, which was safe for consumption as per WHO guidelines. pH showed a marginal change from 6.56 to 6.11 for puran poli stored at 25 ± 2 °C and from 6.62 to 6.33 for puran poli stored at 4 ± 2 °C. Sensory attributes like colour, taste, texture was not affected by the use of medium-chain triglyceride. Overall acceptability of puran Poli was satisfactory for the storage period of 30 days at 4 ± 2 °C.

Estimating relative diglyceride to triglyceride content with localized MRS at 3 T.

It has been previously shown that the MRS sequence stimulated echo acquisition mode (STEAM; mixing time, TM = 20 ms) with an echo time (TE) of 100 ms resolves triglyceride glycerol resonances from that of water at 3 T. The purpose of this work is to determine if STEAM with a TE of 100 ms facilitates relative quantification of diglyceride/triglyceride levels at 3 T. Spectra were obtained from tricaprylin (triglyceride) and dicaprylin (diglyceride) with a range of STEAM TE values (TM = 20 ms). TE values that resulted in two resolved glycerol resonances for triglycerides (rendering them suitable for distinguishing triglyceride contributions from those of diglycerides) were selected. One resonance resides in the 3.85-4.2 ppm spectral range (overlapping the 1,3-diglyceride resonance) and the other in the 4.2-4.6 ppm spectral range (overlapping one of the 1,2-diglyceride resonances). STEAM with TE values of 40 ms and 100 ms (TM = 20 ms) yielded two resolvable triglyceride resonances (tricaprylin phantom), at about 4 ppm and 4.4 ppm. Direct integration of the resonances showed that the former peak has 0.86 and 0.17 times the area of the latter for TE = 40 ms and 100 ms, respectively. Spectra obtained from the phantoms containing mixtures of diglyceride (1,3-dicaprylin) and triglyceride (tricaprylin) were acquired. The triglyceride contribution to the 4 ppm glycerol resonance, a mixture of signal from 1,3-diglyceride and triglyceride, can be approximated from the area of the 4.4 ppm peak, resulting in an estimate of the 1,3-diglyceride contribution. Analysis was performed for STEAM TE = 40 ms and TE = 100 ms spectra acquired from phantoms with 1,3-dicaprylin/tricaprylin weight/weight contents of 2.5%/97.5%, 5%/95%, 10%/90% and 20%/80%. Concentration ratios of 1,3-dicaprylin/tricaprylin estimated with both STEAM TE values resulted in linear correlations with expected concentration ratios (R2 > 0.99).

The Ketogenic Effect of Medium-Chain Triacylglycerides.

Medium-chain triacylglycerides (MCTs) are dietary supplements that can induce ketosis without the need for a traditional ketogenic diet or prolonged fasting. They have the potential to marginally delay the progression of neurodegenerative diseases, such as Alzheimer's disease. However, there have been inconsistencies in reports of the MCT dose-response relationship, which may be due to differences in MCT composition, participant characteristics, and other factors that can influence ketone generation. To resolve these discrepancies, we reviewed studies that investigated the ketogenic effect of MCTs in healthy adults. Aside from the treatment dose, other factors that can influence the ketogenic response, such as accompanying meals, fasting duration, and caffeine intake, were assessed. Based on the available literature, four practical recommendations are made to optimize the ketogenic effect of MCTs and reduce unwanted side effects (primarily gastrointestinal discomfort and diarrhea). First, the starting dose should be either 5 g of octanoic acid [caprylic acid (C8); a component of MCTs] or 5 g of a combination of C8 and decanoic or capric acid (C10; another component of MCTs), and the dose should be progressively increased to 15-20 g of C8. Second, MCTs should be consumed after an overnight fast, without an accompanying meal if tolerable, or with a low-carbohydrate meal. Third, the addition of caffeine may slightly increase the ketogenic response. Fourth, emulsifying the MCTs might increase their ketogenic effect and alleviate side effects.

Delineating penetration enhancer-enriched liquid crystalline nanostructures as novel platforms for improved ophthalmic delivery.

Liquid crystalline nanostructures (LCNs), for instance cubosomes, have been widely used as a promising carrier for drug delivery through the last few years. To date, the ophthalmic application of these platforms was not well explored, and the effect of integrating penetration enhancers (PEs) into LCNs has not been investigated yet. Hence, the present work aimed coupling novel PEs into glyceryl monooleate-based cubosomes for ocular administration. Various enhancers viz, free fatty acids (oleic and linoleic acids), natural terpenes (D-limonene and cineole), medium-chain triglycerides (Captex® 1000 and Captex® 8000), mono-/di-glycerides (Capmul® MCM, Capmul® PG-8, and Capmul® PG-12) were tested at different amounts. The morphology of the formed LCNs was investigated using transmission electron microscopy (TEM). The crystallinity and thermal behavior studies were also conducted. The ocular safety of optimized formulae was tested via hen's egg test-chorioallantoic membrane (HET-CAM), rabbit eye Draize test, and histopathological examinations of ocular tissues. Confocal laser scanning microscopy (CLSM) was utilized to assess the enhanced permeation of fluorescently-labeled LCNs across corneal layers. The acceptable formulations exhibited relatively homogenous particle nano-sizes ranging from 139.26 ± 3.68 to 590.56 ± 24.86 nm carrying negative surface charges. TEM images, X-ray patterns and DSC thermograms demonstrated the influential effect of PEs in developing altered crystalline structures. The ocular compatibility of optimized LCNs was confirmed. The corneal distribution using CLSM proved the disseminated fluorescence intensity of LCNs enriched with oleic acid, Captex® 8000 and Capmul® MCM. Selected LCNs showed good physical stability upon storage and lyophilization. The results demonstrated the efficiency of tailored PE-modified LCNs in enhancing the ocular transport with no evidence of any irritation potential, and hence suggested their prospective applicability in ophthalmic drug delivery.

Ultrasound pretreatment as a novel approach for intensification of lipase catalyzed esterification of tricaprylin.

The current work deals with ultrasound assisted intensification of synthesis of tricaprylin based on the enzyme catalyzed reaction of caprylic acid and glycerol with novel approach of using ultrasound in only the initial stages of the reaction. Two types of immobilized lipases as Lipozyme RM (Rhizomucor miehei) and Novozym 435 (Candida antarctica) have been used in the work. The effect of ultrasonic conditions such as treatment time and power as well as the reaction conditions such as substrate molar ratio, reaction time and enzyme loading on the yield of tricaprylin has been investigated. It was established that the optimum pretreatment conditions were irradiation time as 30min with ultrasonic frequency of 20kHz, supplied power of 240W, 70% duty cycle (7s on 3s off cycle) whereas the optimum reaction conditions were 4:1 molar ratio of caprylic acid to glycerol, enzyme loading as 3% and operating temperature of 50°C. It was also established that reuse of enzymes for 10 cycles was possible without any significant effect on the activity of lipase. It was also conclusively established that compared to the conventional approach of synthesis, ultrasound pretreatment based approach greatly influenced the rate of reaction and maximum tricaprylin yield of 94.8% was achieved in 7h of reaction time under the optimum conditions.

Tricaprylin Alone Increases Plasma Ketone Response More Than Coconut Oil or Other Medium-Chain Triglycerides: An Acute Crossover Study in Healthy Adults.

Background: Ketones are the brain's main alternative fuel to glucose. Dietary medium-chain triglyceride (MCT) supplements increase plasma ketones, but their ketogenic efficacy relative to coconut oil (CO) is not clear. Objective: The aim was to compare the acute ketogenic effects of the following test oils in healthy adults: coconut oil [CO; 3% tricaprylin (C8), 5% tricaprin (C10)], classical MCT oil (C8-C10; 55% C8, 35% C10), C8 (>95% C8), C10 (>95% C10), or CO mixed 50:50 with C8-C10 or C8. Methods: In a crossover design, 9 participants with mean ± SD ages 34 ± 12 y received two 20-mL doses of the test oils prepared as an emulsion in 250 mL lactose-free skim milk. During the control (CTL) test, participants received only the milk vehicle. The first test dose was taken with breakfast and the second was taken at noon but without lunch. Blood was sampled every 30 min over 8 h for plasma acetoacetate and ß-hydroxybutyrate (ß-HB) analysis. Results: C8 was the most ketogenic test oil with a day-long mean ± SEM of +295 ± 155 µmol/L above the CTL. C8 alone induced the highest plasma ketones expressed as the areas under the curve (AUCs) for 0-4 and 4-8 h (780 ± 426 µmol ⋅ h/L and 1876 ± 772 µmol ⋅ h/L, respectively); these values were 813% and 870% higher than CTL values (P < 0.01). CO plasma ketones peaked at +200 µmol/L, or 25% of the C8 ketone peak. The acetoacetate-to-ß-HB ratio increased 56% more after CO than after C8 after both doses. Conclusions: In healthy adults, C8 alone had the highest net ketogenic effect over 8 h, but induced only half the increase in the acetoacetate-to-ß-HB ratio compared with CO. Optimizing the type of MCT may help in developing ketogenic supplements designed to counteract deteriorating brain glucose uptake associated with aging. This trial was registered at clinicaltrials.gov as NCT 02679222.

Amadori products formation in emulsified systems.

The formation of Amadori products (APs) is the key step determining the development of the Maillard reaction (MR). The information on the chemical behaviour of the reaction between amino acids and reducing sugars in emulsions during thermal treatments is scanty and mainly focused on volatile compounds. The aim of this work was to investigate the formation of APs from glucose and two amino acids with different partition coefficients (phenylalanine and leucine) in emulsions. Two submicron oil-in-water (O/W) emulsions consisting of water, tricaprylin and Tween 20 were prepared, thermally treated and the formation of fructose-phenylalanine (Fru-Phe) and fructose-leucine (Fru-Leu) was monitored by mass spectrometry. The concentration of Fru-Phe in submicron emulsions was similar to that in water, while Fru-Leu was reduced up to 47% in the emulsions. These data indicated that partition coefficient of amino acids, determining the reactants location, can substantially influence the MR and the final quality of foods.

Unit cell structure of water-filled monoolein in inverted hexagonal mesophase in the presence of incorporated tricaprylin and entrapped lysozyme.

Molecular dynamics (MD) was employed by means of a specific simulation protocol to investigate the equilibrium structure at 25 °C of the hexagonal inverted (HII) mesophase composed from water, 1-monoolein (GMO), and tricaprylin, with or without entrapped lysozyme. Based on robust and fast MD simulations, the study provides a comprehensive analysis and visualization of the local structure of HII mesophase containing admixtures. The most important physical insight is the possibility to observe the strong self-recovery capacity of the GMO layer, which allows the HII mesophase tubes to reorganize and host lysozyme molecules with a size bigger than the diameter of the water channel. This is a direct message to the experimenters that the HII mesophase has the potential to host molecules larger than the diameter of the water channel. Collective character of the interlipid interactions is outlined, which is not affected by the presence of the cargo and may be the reason for the efficient GMO reorganization. Another important result is the possible explanation of the role of triacylglycerols on the low-temperature stabilization of the HII mesophase. The analysis shows that despite the low amount of tricaprylin, its molecules prevent the extreme inclination of the lipid tails and thus optimize the alignment capacity of the lipid tails layer. The study also reveals that the packing frustration does not depend on the temperature and the presence of admixtures. Hence, it might be numerically defined as a universal invariant parameter of a stable HII mesophase composed of a certain lipid.