Peroxidation potential of lipid emulsions after compounding in all-in-one solutions

Electron Microscopy for the Stability Assessment of Parenteral Nutrition Admixtures: Focus on Precipitation

(1) Background: parenteral nutrition (PN) is indispensable for patients unable to receive oral or enteral feeding. However, the complexity of PN solutions presents challenges regarding stability and compatibility. Precipitation reactions may occur. The most frequent is the formation of calcium phosphate (Ca-P). The different factors influencing these reactions must be considered to ensure patient safety. (2) Methods: eight paediatric PN solutions were prepared, following standard protocols. Samples were stored at room temperature and in a refrigerator. Electron microscopy, coupled with energy dispersive X-ray spectroscopy (EDS), was employed. Precipitates were analysed for composition and morphology. (3) Results: precipitates were observed in all samples, even at day 0. Crystalline structures, predominantly composed of calcium or magnesium, sometimes associated with chlorine or phosphorus, were detected. Additionally, amorphous precipitates, contained heterogeneous compositions, including unexpected elements, were identified. (4) Conclusions: various precipitates, primarily calcium- or magnesium-based, can form in PN solutions, although it is not expected that they can form under the real conditions of use. Calcium oxalate precipitation has been characterised, but the use of organic calcium and phosphate salts appears to mitigate calcium phosphate precipitation. Electron microscopy provides interesting results on NP precipitation, but sample preparation may present technical limitations that affect the interpretation of the results.

Blood Phytosterol Concentration and Genetic Variant Associations in a Sample Population

The main objective of this study was to determine plasma levels of PS and to study SNVs rs41360247, rs4245791, rs4148217, and rs11887534 of ABCG8 and the r657152 SNV at the ABO blood group locus in a sample of a population treated at our hospital, and to determine whether these SNVs are related to plasma PS concentrations. The secondary objective was to establish the variables associated with plasma PS concentrations in adults. Participants completed a dietary habit questionnaire and a blood sample was collected to obtain the following variables: campesterol, sitosterol, sitostanol, lanosterol, stigmasterol, biochemical parameters, and the SNVs. In addition, biometric and demographic variables were also recorded. In the generalized linear model, cholesterol and age were positively associated with total PS levels, while BMI was negatively related. For rs4245791, homozygous T allele individuals showed a significantly lower campesterol concentration compared with C homozygotes, and the GG alleles of rs657152 had the lowest levels of campesterol compared with the other alleles of the SNV. Conclusions: The screening of certain SNVs could help prevent the increase in plasma PS and maybe PNALD in some patients. However, further studies on the determinants of plasma phytosterol concentrations are needed.

One-chamber and two-chamber parenteral nutrition admixtures for pediatric and adult patients: An evaluation of physico-chemical stability at room and cold temperature

OBJECTIVES

The aim of this study was to evaluate the physico-chemical stability of compounded total parenteral nutrition admixtures through peroxidation assay and ultraviolet-visible spectroscopy, high-performance liquid chromatography analysis, nuclear magnetic resonance spectrometry, pH meter, and dynamic light scattering.

METHODS

The present study considered parenteral nutrition (PN) admixtures for pediatric and adult patients. The admixtures were characterized by a high content of vitamins and trace elements. They were prepared in one- or two-chamber bags in the hospital pharmacy using an automatic compounding system in a sterile room with laminar airflow at different temperature conditions and light exposure. The experiment setup comprised fat emulsions, lipid-free PN solutions, and single-chamber bags before and after adding vitamins and trace elements. The stability at room temperature (+25°C) and cold temperature (+2-8°C) was assessed by various means.

RESULTS

Two-compartment admixtures, single-chamber bags, and all-in-one PN supplemented with vitamins and trace elements are stable up until 35, 9, and 7 d, respectively, when protected from light and stored at +2 to 8°C. Also, the supplemented single-chamber PN was found to be stable up to 48 h when stored at +25°C with light exposure.

CONCLUSIONS

The results obtained will help improve PN management at the compounding center and in hospital wards, because they allow for the extension of the validity time frame provided so far by the different formulations and, therefore, therapy scheduling over several days.

The Interplay of Oxidative Stress and ROS Scavenging: Antioxidants as a Therapeutic Potential in Sepsis

Oxidative stress resulting from the disproportion of oxidants and antioxidants contributes to both physiological and pathological conditions in sepsis. To combat this, the antioxidant defense system comes into the picture, which contributes to limiting the amount of reactive oxygen species (ROS) leading to the reduction of oxidative stress. However, a strong relationship has been found between scavengers of ROS and antioxidants in preclinical in vitro and in vivo models. ROS is widely believed to cause human pathology most specifically in sepsis, where a small increase in ROS levels activates signaling pathways to initiate biological processes. An inclusive understanding of the effects of ROS scavenging in cellular antioxidant signaling is essentially lacking in sepsis. This review compiles the mechanisms of ROS scavenging as well as oxidative damage in sepsis, as well as antioxidants as a potent therapeutic. Direct interaction between ROS and cellular pathways greatly affects sepsis, but such interaction does not provide the explanation behind diverse biological outcomes. Animal models of sepsis and a number of clinical trials with septic patients exploring the efficiency of antioxidants in sepsis are reviewed. In line with this, both enzymatic and non-enzymatic antioxidants were effective, and results from recent studies are promising. The usage of these potent antioxidants in sepsis patients would greatly impact the field of medicine.

Specialized Pro-Resolving Lipid Mediators in Neonatal Cardiovascular Physiology and Diseases

Cardiovascular disease remains a leading cause of mortality worldwide. Unresolved inflammation plays a critical role in cardiovascular diseases development. Specialized Pro-Resolving Mediators (SPMs), derived from long chain polyunsaturated fatty acids (LCPUFAs), enhances the host defense, by resolving the inflammation and tissue repair. In addition, SPMs also have anti-inflammatory properties. These physiological effects depend on the availability of LCPUFAs precursors and cellular metabolic balance. Most of the studies have focused on the impact of SPMs in adult cardiovascular health and diseases. In this review, we discuss LCPUFAs metabolism, SPMs, and their potential effect on cardiovascular health and diseases primarily focusing in neonates. A better understanding of the role of these SPMs in cardiovascular health and diseases in neonates could lead to the development of novel therapeutic approaches in cardiovascular dysfunction.

Antioxidant balance in plasma of patients on home parenteral nutrition: A pilot study comparing three different lipid emulsions

BACKGROUND & AIMS

Parenteral nutrition (PN) can supply all essential nutrients to a patient with gastrointestinal insufficiency. However, the sensitivity to lipid peroxidation might increase in those receiving PN, especially home parenteral nutrition (HPN). This study aimed to investigate whether PN affects the antioxidant balance of plasma of HPN patients without comorbidities and whether this balance is influenced by comorbidities and according to the type of lipid emulsion included in the PN.

METHODS

Adult patients on HPN (n = 86) received one of three types of lipid emulsion (based on 1) soyabean oil, 2) olive and soyabean oil or 3) soyabean, coconut, olive and fish oil) in all-in-one mixtures; in addition healthy controls (n = 66) were studied as comparators. HPN patients were classified to the following subgroups: 1) patients without (n = 58) or with (n = 28) comorbidities 2) patients on Intralipid (G_INTRA, n = 53), ClinOleic (G_CLIN, n = 17) or SMOFlipid (G_SMOFn = 16). The activities of total glutathione peroxidase (GSH-Px), selenium dependent glutathione peroxidase (Se-GSHPx) and glutathione S-transferase (GST) in plasma were determined spectrophotometrically. The antioxidant potential of plasma was determined using oxygen radical absorbance capacity (ORAC). The lipid peroxidation marker malondialdehyde (MDA) was analyzed with high performance liquid chromatography.

RESULTS

MDA concentration was the highest in G_INTRA and the lowest in G_SMOF (p < 0.05). G_SMOF also had the highest activity of GSH-Px. No differences in Se-GSHPx, GST and ORAC were observed among G_INTRA, G_CLIN and G_SMOF. Comparing with healthy controls, significantly lower GST (p = 0.0293) and ORAC (p < 0.0001) were observed in the HPN patients. Among all measured parameters only the concentration of MDA was significantly higher in patients with comorbidities compared to those without them. Comorbidities did not influence MDA level in G_INTRA and G_SMOF being still the lowest in G_SMOF (p = 0.0033). In contrast, significantly higher MDA level was observed for G_CLIN in those with vs. without comorbidities (p = 0.0262).

CONCLUSIONS

Patients on HPN have lower antioxidant defenses than healthy controls. The type of lipid emulsion used in HPN affects lipid peroxidation (even after taking into account comorbidities which often involve oxidative stress) being the highest in G_INTRA and the lowest in G_SMOF. Thus, to minimize the risk of oxidative stress, SMOFlipid can be considered in patients in HPN especially for those with comorbidities. ClinOleic can be considered in HPN patients without comorbidities. The observation should be confirmed in larger studies.

Composition and Functionality of Lipid Emulsions in Parenteral Nutrition: Examining Evidence in Clinical Applications

Lipid emulsions (LEs), an integral component in parenteral nutrition (PN) feeding, have shifted from the primary aim of delivering non-protein calories and essential fatty acids to defined therapeutic outcomes such as reducing inflammation, and improving metabolic and clinical outcomes. Use of LEs in PN for surgical and critically ill patients is particularly well established, and there is enough literature assigning therapeutic and adverse effects to specific LEs. This narrative review contrarily puts into perspective the fatty acid compositional (FAC) nature of LE formulations, and discusses clinical applications and outcomes according to the biological function and structural functionality of fatty acids and co-factors such as phytosterols, α-tocopherol, emulsifiers and vitamin K. In addition to soybean oil-based LEs, this review covers clinical studies using the alternate LEs that incorporates physical mixtures combining medium- and long-chain triglycerides or structured triglycerides or the unusual olive oil or fish oil. The Jaded score was applied to assess the quality of these studies, and we report outcomes categorized as per immuno-inflammatory, nutritional, clinical, and cellular level FAC changes. It appears that the FAC nature of LEs is the primary determinant of desired clinical outcomes, and we conclude that one type of LE alone cannot be uniformly applied to patient care.

Physicochemical stable standard all-in-one parenteral nutrition admixtures for infants and children in accordance with the ESPGHAN/ESPEN guidelines

OBJECTIVE

Because there are almost no standard all-in-one parenteral nutrition admixtures available for infants and children, the aim was to develop standard two-compartment parenteral nutrition bags for different weight categories based on the ESPGHAN/ESPEN (European Society of Paediatric Gastroenterology, Hepatology and Nutrition/European Society for Clinical Nutrition and Metabolism) guidelines. The 1 g/kg/d lipid version for the 3 to 10 kg weight category (PED1) was assessed for short- and long-term physicochemical stability with the ability to add additional electrolytes (PED1+E).

METHODS

The lipid compartment A and the all-in-one admixture of A + B + vitamins + trace elements were assessed physically by visual inspection, Sudan red test, pH measurement, and lipid droplet size distribution. Chemical stability for compartment A was evaluated by quantitative analyses of non-esterified fatty acids and peroxide content. The glucose-amino acid-electrolyte compartment B was evaluated physically by visual inspection, measuring particle contamination and pH. Chemical stability was assessed by discoloration, quantitative analyses of glucose, and the amino acids L-cysteine, L-tyrosine, and L-tryptophan.

RESULTS

No phase separation or coalescence occurred, and the mean droplet size diameter did not exceed 0.5 µm. Peroxide content and non-esterified fatty acids concentration of compartment A remained well below the limit of acceptation. No precipitation was detected for compartment B; only a slight yellow discoloration was noted at 80 d. Concentrations of glucose, L-tyrosine, and L-tryptophan remained stable; only L-cysteine decreased significantly from its initial concentration.

CONCLUSION

The two-compartment PED1 and PED1+E admixtures are stable up to 80 d 2° to 8°C + 24 h room temperature (RT) with an additional 7 d 2° to 8°C + 48 h RT after mixing and addition of vitamins and trace elements.

New Parenteral Lipid Emulsions for Clinical Use

Routine use of parenteral lipid emulsions (LE) in clinical practice began in 1961, with the development of soybean oil (SO) - based LE. Although clinically safe, experimental reports indicated that SO-based LE could exert a negative influence on immunological functions. Those findings were related to its absolute and relative excess of omega-6 polyunsaturated fatty acids (PUFA) and the low amount of omega-3 PUFA and also to its high PUFA content with an increased peroxidation risk. This motivated the development of new LE basically designed along the reduction of omega-6 PUFA and the omega-3 PUFA addition in order to obtain balanced levels of the omega-6/omega-3 ratio. The new LE for clinical use (available in Europe and South America) are differentiated by their content in polyunsaturated (omega-6 and omega-3), monounsaturated, and saturated fatty acids (FA), as well as FA source of their origin, including soy, coconut, olive, and fish oil. This article presents the new LE nutrition and energy functions but also its biochemical, metabolic, and immunomodulating aspects, according to their FA content. LE at 20% when infused from 1.0 to 2.0 g/kg body weight/day rates, either alone or in association with amino acids and glucose, are safe and well tolerated in routine clinical practice. LE combining SO with medium-chain triglycerides and/or olive oil have less omega-6 PUFA and are better metabolized, with less inflammatory and immunosuppressive effects than in relation to pure SO-based LE. The omega-3 PUFA used alone or as component of a new and complex LE (soy, MCT, olive and fish oil) has demonstrated anti-inflammatory and immunomodulatory effects.

Tocopherol and tocotrienol homologs in parenteral lipid emulsions

Parenteral lipid emulsions, which are made of oils from plant and fish sources, contain different types of tocopherols and tocotrienols (vitamin E homologs). The amount and types of vitamin E homologs in various lipid emulsions vary considerably and are not completely known. The objective of this analysis was to develop a quantitative method to determine levels of all vitamin E homologs in various lipid emulsions. An HPLC system was used to measure vitamin E homologs using a Pinnacle DB Silica normal phase column and an isocratic, n-hexane:1,4 dioxane (98:2) mobile phase. An optimized protocol was used to report vitamin E homolog concentrations in soybean oil-based (Intralipid®, Ivelip®, Lipofundin® N, Liposyn® III, and Liposyn® II), medium- and long-chain fatty acid-based (Lipofundin®, MCT and Structolipid®), olive oil-based (ClinOleic®), and fish oil-based (Omegaven®) and mixture of these oils-based (SMOFlipid®, Lipidem®) commercial parenteral lipid emulsions. Total content of all vitamin E homologs varied greatly between different emulsions, ranging from 57.9 to 383.9 µg/mL. Tocopherols (α, β, γ, δ) were the predominant vitamin E homologs for all emulsions, with tocotrienol content < 0.3%. In all of the soybean emulsions, except for Lipofundin® N, the predominant vitamin E homolog was γ-tocopherol, which ranged from 57–156 µg/mL. ClinOleic® predominantly contained α-tocopherol (32 µg/mL), whereas α-tocopherol content in Omegaven® was higher than most of the other lipid emulsions (230 µg/mL).

Adduct of malondialdehyde to hemoglobin: a new marker of oxidative stress that is associated with significant morbidity in preterm infants

Preterm infants (PT) are particularly exposed to oxidative stress (OS), and a blood-sparing marker, the malondialdehyde adduct to hemoglobin (MDA-Hb), may be useful to accurately assess OS-related neonatal morbidity. In a prospective study, MDA-Hb concentrations were assessed in two groups of PT, one with and one without severe neonatal morbidity as estimated by a composite index of severe morbidity (ISM). All PT born in a single tertiary care NICU (<32 weeks and birth weight <1500 g) were consecutively included. MDA-Hb and blood glutathione (GSH) concentrations were measured by liquid chromatography-mass spectrometry during the first 6 weeks of life. Linear regressions and a multilevel model were fitted to study the relationship between MDA-Hb or GSH and ISM. Of the 83 PT (mean ± SD: 28.3 ± 2 weeks, 1089 ± 288 g), 21% presented severe neonatal morbidity. In the multivariate model, MDA-Hb concentrations were significantly higher in the ISM+ group than in the ISM– group during the first 6 weeks of life (P = 0.009). No significant difference in GSH concentrations was observed between groups (P = 0.180). MDA-Hb is a marker of interest for estimating oxidative stress in PT and could be useful to evaluate the impact of strategies to improve perinatal outcomes.

Lipid peroxidation in all-in-one admixtures for preterm neonates: impact of amount of lipid, type of lipid emulsion and delivery condition

AIM

To evaluate the effect of lipid emulsion composition and delivery condition on lipid peroxidation in typical all-in-one parenteral admixtures for preterm neonates.

METHODS

Malonedialdehyde (MDA) concentrations were assessed in different all-in-one admixtures. We evaluated the effects of fat blend (three lipid emulsions) and the amount of lipids, as well as the effects of protecting bags and/or tubing from ambient light and storage for 72 h. MDA was measured by liquid chromatography/mass spectrometry.

RESULTS

Three hundred and sixty samples were collected from 114 admixtures. Neither the type of lipid (p = 0.43) nor the interaction between light and type of lipid (p = 0.49) had any influence on final MDA concentrations, but the increase in MDA concentration at 24 h (T(24)) was related to light exposure (p < 0.001). The increase in MDA concentration was related to the increase in lipid amount in the admixture at T(0) (r = 0.77) and T(24) (r = 0.86). MDA concentrations in solutions stored for 72 h showed no significant increase, with no difference between the three lipid emulsions (p = 0.69).

CONCLUSION

All-in-one admixtures may be interesting for the parenteral nutrition of preterm neonates. Protection from light and restricting the amount of lipid to what is required for appropriate energy provision are essential to limit lipid peroxidation.

Effect of medium/ω-6 long chain triglyceride-based emulsion on leucocyte death and inflammatory gene expression

Lipid emulsion (LE) containing medium/ω-6 long chain triglyceride-based emulsion (MCT/ω-6 LCT LE) has been recommended in the place of ω-6 LCT-based emulsion to prevent impairment of immune function. The impact of MCT/ω-6 LCT LE on lymphocyte and neutrophil death and expression of genes related to inflammation was investigated. Seven volunteers were recruited and infusion of MCT/ω-6 LCT LE was performed for 6 h. Four volunteers received saline and no change was found. Blood samples were collected before, immediately afterwards and 18 h after LE infusion. Lymphocytes and neutrophils were studied immediately after isolation and after 24 and 48 h in culture. The following determinations were carried out: plasma-free fatty acids, triacylglycerol and cholesterol concentrations, plasma fatty acid composition, neutral lipid accumulation in lymphocytes and neutrophils, signs of lymphocyte and neutrophil death and lymphocyte expression of genes related to inflammation. MCT/ω-6 LCT LE induced lymphocyte and neutrophil death. The mechanism for MCT/ω-6 LCT LE-dependent induction of leucocyte death may involve changes in neutral lipid content and modulation of expression of genes related to cell death, proteolysis, cell signalling, inflammatory response, oxidative stress and transcription.

Organisation, regulations, preparation and logistics of parenteral nutrition in hospitals and homes; the role of the nutrition support team - Guidelines on Parenteral Nutrition, Chapter 8

PN (parenteral nutrition) should be standardised to ensure quality and to reduce complications, and it should be carried out in consultation with a specialised nutrition support team whenever possible. Interdisciplinary nutrition support teams should be established in all hospitals because effectiveness and efficiency in the implementation of PN are increased. The tasks of the team include improvements of quality of care as well as enhancing the benefit to cost ratio. Therapeutic decisions must be taken by attending physicians, who should collaborate with the nutrition support team. “All-in-One” bags are generally preferred for PN in hospitals and may be industrially manufactured, industrially manufactured with the necessity to add micronutrients, or be prepared “on-demand” within or outside the hospital according to a standardised or individual composition and under consideration of sterile and aseptic conditions. A standardised procedure should be established for introduction and advancement of enteral or oral nutrition. Home PN may be indicated if the expected duration of when PN exceeds 4 weeks. Home PN is a well established method for providing long-term PN, which should be indicated by the attending physician and be reviewed by the nutrition support team. The care of home PN patients should be standardised whenever possible. The indication for home PN should be regularly reviewed during the course of PN.

Neonatology/Paediatrics - Guidelines on Parenteral Nutrition, Chapter 13

There are special challenges in implementing parenteral nutrition (PN) in paediatric patients, which arises from the wide range of patients, ranging from extremely premature infants up to teenagers weighing up to and over 100 kg, and their varying substrate requirements. Age and maturity-related changes of the metabolism and fluid and nutrient requirements must be taken into consideration along with the clinical situation during which PN is applied. The indication, the procedure as well as the intake of fluid and substrates are very different to that known in PN-practice in adult patients, e.g. the fluid, nutrient and energy needs of premature infants and newborns per kg body weight are markedly higher than of older paediatric and adult patients. Premature infants <35 weeks of pregnancy and most sick term infants usually require full or partial PN. In neonates the actual amount of PN administered must be calculated (not estimated). Enteral nutrition should be gradually introduced and should replace PN as quickly as possible in order to minimise any side-effects from exposure to PN. Inadequate substrate intake in early infancy can cause long-term detrimental effects in terms of metabolic programming of the risk of illness in later life. If energy and nutrient demands in children and adolescents cannot be met through enteral nutrition, partial or total PN should be considered within 7 days or less depending on the nutritional state and clinical conditions.

Parenteral lipid emulsions in paediatrics

PURPOSE OF REVIEW

Lipid emulsions are crucial for providing essential fatty acids and energy in infants and children requiring parenteral nutrition. There is ongoing debate about the optimal composition of lipid emulsions and the optimal timing for introducing lipids to the parenteral nutrition of premature infants in order to enhance the benefits and to minimize the risk of complications.

RECENT FINDINGS

Several studies have investigated the effects of early compared with late administration of lipid emulsions. A meta-analysis demonstrated that early introduction of lipid emulsions does not improve short-term growth or prevent morbidity and mortality in preterm infants. On the other hand, early introduction of lipid emulsions was not shown to increase the risk of complications. A number of studies have investigated the effects of different fatty acid compositions in lipid emulsions on peroxidation. In-vitro findings suggest that lipid peroxidation is related to the polyunsaturated fatty acid content and inversely related to the alpha-tocopherol/polyunsaturated fatty acid ratio of the fat emulsion. The composition of lipid emulsions has also been shown to influence fatty acid metabolism. A mixture of medium-chain and long-chain triglycerides seems to enhance the incorporation of essential fatty acids and long-chain polyunsaturated fatty acids into circulating lipids when compared with an emulsion containing only long-chain triglycerides.

SUMMARY

Although the composition of lipid emulsions has been demonstrated to influence peroxidation and fatty acid metabolism, outcome studies are needed to confirm advantageous effects.

Efficacy and safety of an olive oil-based intravenous fat emulsion in adult patients on home parenteral nutrition

BACKGROUND

The most frequently used intravenous lipid emulsions are composed of 100% long chain triacylglycerols from soybean oil or of 50% long chain triacylglycerols-50% medium chain triacylglycerols. A newer emulsion, ClinOleic 20% containing 80% olive oil and 20% soybean oil, was suggested to reduce lipid peroxidation and immune function impairment.

AIM

To assess ClinOleic 20%'s efficacy, safety and effect upon systemic inflammatory parameters in adults on home parenteral nutrition.

METHODS

In stable home parenteral nutrition patients, the initial intravenous lipid emulsion was changed for ClinOleic 20%. Nutritional status, clinical and biological tolerance, and systemic inflammatory markers were analysed before and after 1 and 3 months of home parenteral nutrition, with ClinOleic 20% as intravenous lipid emulsion.

RESULTS

Clinical and biological nutritional markers and inflammatory parameters did not differ between day 0 and month +3. There was no essential fatty acids deficiency. No side-effects were reported. Three of five patients presenting with migraine during home parenteral nutrition infusion at day 0 felt consistently better at month +3.

CONCLUSIONS

ClinOleic 20% is safe and efficient in adult home parenteral nutrition. It maintains normal essential fatty acids status and did not influence inflammatory parameters. In contrast to studies in preterm infants or paediatric patients, no effect on vitamin E concentration or lipid peroxidation was observed.

Potential usefulness of olive oil-based lipid emulsions in selected situations of home parenteral nutrition-associated liver disease

Long-term (i.e. home) parenteral nutrition has been advocated to be responsible for several metabolic complications among which hepatic disorders have long been the most relevant in view of patients' prognosis. The increased knowledge of the pathophysiologic factors associated to parenteral nutrition-related liver disease as well as the regular improvement of the components and the techniques used for parenteral nutrition leaded progressively to a better prevention of these side effects. This case report focuses on the potential interest of olive oil-based lipid emulsions in home parenteral nutrition patients, in selected situations of home parenteral nutrition-associated metabolic liver disease.