Effects of glucose or fat calories in total parenteral nutrition on fat metabolism and systemic inflammation in rats

The Impact of Glucose-Based or Lipid-Based Total Parenteral Nutrition on the Free Fatty Acids Profile in Critically Ill Patients

Introduction: Our study aim was to assess how the macronutrient intake during total parenteral nutrition (TPN) modulates plasma total free fatty acids (FFAs) levels and individual fatty acids in critically ill patients. Method: Adult patients aged 18–80, admitted to the intensive care unit (ICU), who were indicated for TPN, with an expected duration of more than three days, were included in the study. Isoenergetic and isonitrogenous TPN solutions were given with a major non-protein energy source, which was glucose (group G) or glucose and lipid emulsions (Smof lipid; group L). Blood samples were collected on days 0, 1, 3, 6, 9, 14, and 28. Results: A significant decrease (p < 0.001) in total FFAs occurred in both groups with a bigger decrease in group G (p < 0.001) from day 0 (0.41 ± 0.19 mmol∙L⁻¹) to day 28 (0.10 ± 0.07 mmol∙L⁻¹). Increased palmitooleic acid and decreased linoleic and docosahexaenoic acids, with a trend of increased mead acid to arachidonic acid ratio, on day 28 were observed in group G in comparison with group L. Group G had an insignificant increase in leptin with no differences in the concentrations of vitamin E, triacylglycerides, and plasminogen activator inhibitor-1. Conclusion: Decreased plasma FFA in critically ill patients who receive TPN may result from increased insulin sensitivity with a better effect in group G, owing to higher insulin and glucose dosing and no lipid emulsions. It is advisable to include a lipid emulsion at the latest from three weeks of TPN to prevent essential fatty acid deficiency.

Review article: diagnosis and management of intestinal failure-associated liver disease in adults

BACKGROUND

Hepatic disturbances in the context of intestinal failure and parenteral nutrition (PN) are frequently encountered and carry a significant burden of morbidity and sometimes mortality. The term intestinal failure-associated liver disease (IFALD) refers to liver injury due to intestinal failure and associated PN, in the absence of another evident cause of liver disease, encompassing a spectrum of conditions from deranged liver enzymes, steatosis/ steatohepatitis, cholestasis as well as progressive fibrosis, cirrhosis and end-stage liver disease.

AIMS

To present an up to date perspective on the diagnosis/definition, aetiologies and subsequent management of IFALD and to explore future consideration for the condition, including pharmacological therapies RESULTS: In adults using long-term PN for benign chronic intestinal failure, 1%-4% of all deaths are attributed to IFALD. The aetiology of IFALD is multifactorial and can be broadly divided into nutritional factors (eg lipid emulsion type) and patient-related factors (eg remaining bowel anatomy). Given its multifaceted aetiology, the management of IFALD requires clinicians to investigate a number of factors simultaneously. Patients with progressive liver disease should be considered for combined liver-intestine transplantation, although multivisceral grafts have a worse prognosis. However, there is no established non-invasive method to identify progressive IFALD such that liver biopsy, where appropriate, remains the gold standard.

CONCLUSION

A widely accepted definition of IFALD would aid in diagnosis, monitoring and subsequent management. Management can be complex with a number of factors to consider. In the future, dedicated pharmacological interventions may become more prominent in the management of IFALD.

A Comparison of Fish Oil Sources for Parenteral Lipid Emulsions in a Murine Model

BACKGROUND

Fat emulsions are important components of parenteral nutrition (PN). Fish oil (FO) emulsions reverse cholestasis in PN-associated liver disease. There are 2 FO monographs. One is "FO; rich in omega-3 fatty acids" (NFO). The other, "omega-3 acids," (PFO), is enriched in omega-3 fatty acids, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The purpose of this study is to compare the effects of 20% NFO and PFO emulsions produced in the laboratory in a murine model.

METHODS

Emulsions were compounded containing different oils: soybean oil (SO), NFO, and two PFOs differing in percentage of fatty acids as triglycerides (PFO66 and PFO90). Chow-fed mice received saline, one of the above emulsions, or a commercial FO (OM) intravenously (2.4 g/kg/day) for 19 days. On day 19, animals were euthanized. Livers, spleens, and lungs were procured for histologic analysis.

RESULTS

OM, SO, NFO, and PFO90 were well-tolerated clinically. PFO66 resulted in tachypnea and lethargy for ~1 minute following injections. At euthanasia, PFO66 and PFO90 groups had organomegaly. Histologically, these groups had splenic and hepatic fat-laden macrophages, and lungs had scattered fat deposits. Other groups had normal organs.

CONCLUSIONS

PFO emulsions present an attractive possibility for improving inflammation in PN-dependent patients by concentrating anti-inflammatory EPA and DHA. However, 20% PFO emulsions were poorly tolerated and precipitated adverse end organ sequelae, suggesting that they may not be safe. Development of novel manufacturing methods may achieve safe 20% PFO parenteral emulsions, but by established formulation methods, these emulsions were clinically suboptimal despite meeting pharmacopeial standards.

Intravenous Lipid Emulsions in Parenteral Nutrition

Fat is an important macronutrient in the human diet. For patients with intestinal failure who are unable to absorb nutrients via the enteral route, intravenous lipid emulsions play a critical role in providing an energy-dense source of calories and supplying the essential fatty acids that cannot be endogenously synthesized. Over the last 50 y, lipid emulsions have been an important component of parenteral nutrition (PN), and over the last 10-15 y many new lipid emulsions have been manufactured with the goal of improving safety and efficacy profiles and achieving physiologically optimal formulations. The purpose of this review is to provide a background on the components of lipid emulsions, their role in PN, and to discuss the lipid emulsions available for intravenous use. Finally, the role of parenteral fat emulsions in the pathogenesis and management of PN-associated liver disease in PN-dependent pediatric patients is reviewed.

Diet-induced hyperinsulinemia accelerates growth of androgen-independent PC-3 cells in vitro

We investigated the effect of insulin and diet-induced hyperinsulinemia on the growth of the PC-3 cells in vitro and discerned the growth promoting effect of insulin in the androgen-independent cells. Sprague-Dawley rats were kept on a high-fat diet for 4 wk for the induction of insulin resistance and hyperinsulinemia. Insulin alone or serum of the rats kept on either normal-pellet diet or high-fat diet was used to stimulate the serum-starved PC-3 cells growth in culture. S961, a high-affinity insulin-receptor antagonist, was used to confirm the insulin-mediated effects. Significant impairment in the glucose disposal rate and increase in the serum glucose and insulin levels was observed in the high-fat-diet-fed rats. The media supplemented with the serum of the high-fat-diet-fed rats accelerated the growth of the PC-3 cells in comparison to that of normal-pellet-diet-fed rats. Insulin treatment led to accelerated growth of the serum-starved PC-3 cells in a dose-dependent manner and inhibited by the S961 pretreatment. Insulin and serum of the diet-induced hyperinsulinemic rats promote the growth of androgen-independent prostate cancer PC-3 cells. Further, our results provide support for the concept that diet-associated elevation in insulin level may augment the growth of prostate cancer cells.