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TOP NUTRITION NEWSLETTER VOLUME 1, NO 12: DECEMBER 1998 Editorial This is the last issue of TOP NUTRITION NEWSLETTER in 1998.In this issue, enteral glutamine in VLBW infants,oxidative stress, short-chain fatty acids, are updated for your interest. Enteral glutamine is the conditionally essential amino acid in stress condition like severe trauma, burns, major surgery in adults. Enteral Glutamine Supplementation for VLBW Infants Decreases Hospital Costs is the first evidence for decreased hospital costs in VLBW neonates who receive enteral glutamine supplementation. Although it has been known for many years that poor nutrition can affect host response to infection, this is the first report of host nutrition affecting the genetic sequence of a pathogen. In this article of DIETARY OXIDATIVE STRESS AND THE POTENTIATION OF VIRAL INFECTION, it is worth to know how importance the dietary antioxidants are to prevent viral infections. Short-chain fatty acids (SCFA) are the C2-C5 organic acids produced in the colon by bacterial fermentation of dietary fiber or nonabsorbed starch.SCFA , especially butyrate, play an essential role in colonocyte proliferation. During period of SCFA deprivation, there is mucosal atrophy, loss of integrity of the mucosal barrier, and impaired immune function when diets low in fiber are ingested. Animal and human studies of SCFA are updated for your consideration of application in clinical practice. Intake of vitamins especially antioxidant vitamin E and cataract development study " Long-Term Vitamin E Use Curbs Cataracts"was an interesting study by National Eye Institute. 744 subjects were interviewed and analysed. With the highest 20 percent of plasma vitamin E at the start of the study had only 58 percent the risk of lens opacity as those with the lowest 20 percent. Overall, vitamin E supplementation was associated with a 57 percent risk reduction compared with the risk for those who did not take the vitamin. It appears, however, that vitamin E exerts a protective effect only over time. By the end of the study, people who had taken vitamin E supplements for less than five years reduced their risk by just less than 20 percent, whereas those taking the antioxidant for more than five years lowered their risk by 74 percent. I wish all my readers a happy and peaceful Festive Season. Let me remind you that moderate drinking and eating is the mainstay for your healthy life. Happy Reading. Dr Shwe Win Editor
Enteral Glutamine Supplementation for VLBW Infants Decreases Hospital Costs Source: JPEN 1998;22:352-356. There is growing evidence that glutamine may be a conditionally essential amino acid for critically ill patients, including preterm infants cared for in neonatal intensive care units (NICUs). In a randomized study of 68 VLBW infants, the authors found evidence of lower morbidity in a group fed glutamine-supplemented preterm infant formula from postnatal day 3 to day 30 than in a group fed a standard formula. The median costs for hospitalization, radiology, pharmacy, laboratory, and the NICU, and the median number of utilization units were reduced with glutamine supplementation. This study provides the first evidence for decreased hospital costs in VLBW neonates who receive enteral glutamine supplementation. There was a lower incidence of hospital acquired sepsis and evidence of improved tolerance tp enteral feeding in the glutamine supplemented group.The hospitalization costs were significantly lower in glutamine supplemented group. Editor's comment: In adult humans, glutamine-supplemented TPN has been shown to decrease hospital-acquired infection and saved costs significantly,and improve nitrogen balance and protein synthesis. The lower costs for glutamine-supplemented group may be due to lower intensity of care and fewer utilization units (less time on mechanical ventilation). Decreased hospitalization costs should be consistent with decreased morbidity. We need further validation in a large samples before routine recommendation is established.
Source: Annu. Rev. Nutr. 1998. 18:93-116.
This review article presented selenium, vitamin E, omega-3 fatty acids deficiencies as oxidative stress, iron overload on increase lipid peroxidation and heart damage, and gold compounds on increased virulence of viral infections.The possible mechanisms for the effect of oxidative stress on the viral genome are direct oxidative damage to viral RNA and viral selection via quasispecies. Role of nutrition in emerging viral diseases in China (Keshan disease) and in Cuba (optic and peripheral neuropathy) are two examples of the nutrient deficiencies and oxidative stress. Keshan disease may involve selenium and optic and peripheral neuropathy may due to low animal protein, fat and vitamins. Editor's comment: Several environmental variables (global warming, changes in industrial or agricultural processes, improvement in personal hygiene, etc.) and not nutritional factors have been discusssed in the context of viral evolution. One wonders how many outbreaks of disease attributed to a nutritional deficiency are actually the result of a viral infection that has changed its pathogenesis as a result of replicating in a nutritionally deficient host.We need to examine the nutrition factor and stimulate collaboration between nutritionists and virologists to investigate some of these problems. Source:Gastro Clinics N Am 1998;27(2):387-402. SCFA are the C2-C5 organic acids produced in the colon by bacterial fermentation of dietary fiber or nonabsorbed starch. The SCFA, acetate, butyrate, and propionate, account for approximately 80% of the SCFA, produced in humans.These agents provide greater than 70% of the metabolic energy supply for the colonocyte, with butyrate serving as the most important oxidative fuel. SCFA are important in the maintenance of colonic cellular structure and function and as an energy source for bacteria. Additionally, SCFA enhance mesenteric and colonic blood flow and have a vasodilaatory effect. SCFA enhance gut hormone production, mediate sodium and water absorption in the colon, and stimulate the autonomic nervous system. SCFA , especially butyrate, play an essential role in colonocyte proliferation. During period of SCFA deprivation, there is mucosal atrophy, loss of integrity of the mucosal barrier, and impaired immune function when diets low in fiber are ingested.Restoration of dietary fiber or enemas of SCFA help restore mucossal growth and colonocyte proliferation. SCFA, primarily administered in enema form, may be clinically efficacious in certain disease states. Patients with defunctionalized distal colon develop active inflammation (diversion colitis) related to loss of nutrients from the diverted fecal stream. Whwn continuity of the bowel is restored, the diversion colitis remits. For patientswho cannot undergo reanastomosis, the inflammation may be ongoing, severe, and recalcitrant to standard medical therapy. Instillation of SCFA enemas appears to attenuate the activity of inflammation. In a controlled study of 5 patients with diversion colitis, SCFA enemas were compared to saline irrigation. Over a period of 4 to 6 weeks, there was both endoscopic and histologic improvement in the treated group. Treatment of diversion colitis with SCFA seems to require long term therapy because shorter duration of treatment appears to be ineffective. Because there are striking histologic similarities between diversion colitis and ulcerative proctitis, studies using SCFA hav ebeen initiated in patients with ulcerrative colitis.
Long-Term Vitamin E Use Curbs
Cataracts Taking vitamins, particularly vitamin E, was associated with reduced cataract development in a four-year study conducted by M. Cristina Leske, M.D., of the University Medical Center at Stony Brook, N.Y. The research was conducted as part of an NIH National Eye Institute (NEI) epidemiological effort that measured changes in lens opacity as well as risk factors for cataract growth. Researchers interviewed 744 participants (average age 65) about vitamin intake and then studied changes in the opaqueness, or cloudiness, of their eye lenses to determine if cataracts were developing. Initially, 40 percent used vitamins. People who reported taking regular multivitamin supplements reduced their risk of increased lens opacity by 31 percent after four years. The results are dramatic, considering that the authors defined "regular" supplement use as "at least once a week"--considerably less frequent than for most vitamin users. The results for vitamin E use are even more striking. Subjects with the highest 20 percent of plasma vitamin E at the start of the study had only 58 percent the risk of lens opacity as those with the lowest 20 percent. Overall, vitamin E supplementation was associated with a 57 percent risk reduction compared with the risk for those who did not take the vitamin. It appears, however, that vitamin E exerts a protective effect only over time. By the end of the study, people who had taken vitamin E supplements for less than five years reduced their risk by just less than 20 percent, whereas those taking the antioxidant for more than five years lowered their risk by 74 percent. Editor's comment: Because this was a longitudinal study--researchers followed subjects' progress but did not closely monitor them--the findings are not conclusive evidence that vitamin E prevents cataracts. More proof may be provided by the NEI's Age Related Eye Disease Study, in which participants are randomly assigned to take a supplement or a placebo.
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