title: Influence of fish to soybean oil ratio on hepatic mononuclear cell function and survival after intraportal bacterial challenge in parenterally fed mice.
abstract: BACKGROUND
  Parenteral nutrition (PN) is indispensable for meeting the caloric and substrate needs of patients who cannot receive adequate amounts of enteral nutrition. However, PN decreases hepatic mononuclear cell (MNC) numbers and impairs their functions. We examined the effects of various ratios of ω-3 to ω-6 polyunsaturated fatty acids on hepatic MNC number and function in a murine model. We focused on serum liver enzymes, lipid metabolism, cytokine production, histopathology, and the outcomes of an intraportal bacterial challenge.
  
  
  METHODS
  In experiment 1, male Institute of Cancer Research mice were randomized to CHOW, 67%, 33%, 16%, 8%, 4%, and 0% fish oil (FO)-PN groups. After receiving their respective diets for 5 days, 1.0 × 10(7) Pseudomonas aeruginosa were delivered by intraportal injection. Survival was observed ≤ 7 days after injection. Liver histologies after intraportal bacterial challenge were examined in the CHOW, 33%, 8%, and 0% FO-PN groups. In experiment 2, the mice were divided into 4 groups: CHOW, 33%, 8%, and 0% FO-PN. After the mice had been fed for 5 days, MNC were isolated. Hepatic MNC were counted and cytokine productions (tumor necrosis factor [TNF]-α and interleukin [IL]-10) by MNC in response to lipopolysaccharide (LPS) were measured. Blood samples were analyzed for lipid metabolism and hepatobiliary biochemical parameters. Liver histologies were also examined.
  
  
  RESULTS
  In experiment 1, survival times were significantly shorter in the 4% and 0% FO-PN groups than in the CHOW group. Survival rates at 168 hours were 100%, 64%, 86%, 73%, 67%, 11%, and 13% in the CHOW, 67%, 33%, 16%, 8%, 4%, and 0% FO-PN groups, respectively. At 72 hours after intraportal bacterial challenge, the 0% FO-PN group showed severe tissue damage, whereas such damage was reduced in the 8% and 33% FO-PN groups. In experiment 2, the CHOW, 33%, 8%, and 0% FO-PN groups showed LPS dose-dependent increases in TNF-α levels. IL-10 levels were also LPS dose-dependently increased in the CHOW and 33% FO-PN groups. However, no marked changes were observed in response to LPS stimulation in either the 8% or the 0% FO-PN group. There were no differences in serum levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, or total bilirubin among these 4 groups. In the 0% FO-PN group, serum total cholesterol levels were greater than those in the 8% and 33% FO-PN groups. Without bacterial challenge, livers from the 0% FO-PN group showed steatosis, but these changes were attenuated in the 8% and 33% FO-PN groups.
  
  
  CONCLUSIONS
  The 30-40% ratio of FO to soybean oil with 20% of total calories supplied by lipid seems to be the best PN for preservation of hepatic MNC number and function.
authors: Department of Surgery, National Defense Medical College, Saitama, Japan. Electronic address: tmoriya@ndmc.ac.jp.
authors: Tomoyuki
authors: T
authors: Moriya
authors: Surgical Center, University of Tokyo, Tokyo, Japan.
authors: Kazuhiko
authors: K
authors: Fukatsu
authors: Department of Pathology, National Defense Medical College, Saitama, Japan.
authors: Keiichi
authors: K
authors: Iwaya
authors: Division of Traumatology, National Defense Medical College Research Institute, Saitama, Japan.
authors: Midori
authors: M
authors: Noguchi
authors: Surgical Center, University of Tokyo, Tokyo, Japan.
authors: Satoshi
authors: S
authors: Murakoshi
authors: Department of Surgery, National Defense Medical College, Saitama, Japan.
authors: Koichi
authors: K
authors: Okamoto
authors: Department of Surgery, National Defense Medical College, Saitama, Japan.
authors: Toru
authors: T
authors: Kubo
authors: Division of Traumatology, National Defense Medical College Research Institute, Saitama, Japan.
authors: Daizoh
authors: D
authors: Saitoh
authors: Department of Surgery, National Defense Medical College, Saitama, Japan.
authors: Kazuo
authors: K
authors: Hase
authors: Department of Surgery, National Defense Medical College, Saitama, Japan.
authors: Junji
authors: J
authors: Yamamoto
mesh_terms: D000818:Animals; D016207:Cytokines / Q000378:metabolism; D004195:Disease Models, Animal; D005395:Fish Oils / Q000008:administration & dosage / Q000494:pharmacology*; D007275:Injections, Intravenous; D007963:Leukocytes, Mononuclear / Q000187:drug effects* / Q000502:physiology*; D050356:Lipid Metabolism / Q000187:drug effects; D008099:Liver / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D010288:Parenteral Nutrition; D011169:Portal Vein / Q000382:microbiology; D011552:Pseudomonas Infections / Q000209:etiology / Q000401:mortality*; D011550:Pseudomonas aeruginosa; D013024:Soybean Oil / Q000008:administration & dosage / Q000494:pharmacology*; D015996:Survival Rate
chemical_list: D016207:Cytokines; D005395:Fish Oils; D013024:Soybean Oil