Mitochondria-initiated apoptosis triggered by oxidative injury play a role in total parenteral nutrition-associated liver dysfunction in infant rabbit model

Nuclear respiratory factor 1 regulates super enhancer-controlled SPIDR to protect hepatocellular carcinoma cells from oxidative stress

BACKGROUND

Cellular response to oxidative stress plays significant roles in hepatocellular carcinoma (HCC) development, yet the exact mechanism by which HCC cells respond to oxidative stress remains poorly understood. This study aimed to investigate the role and mechanism of super enhancer (SE)-controlled genes in oxidative stress response of HCC cells.

METHODS

The GSE112221 dataset was used to identify SEs by HOMER. Functional enrichment of SE-controlled genes was performed by Metascape. Transcription factors were predicted using HOMER. Prognosis analysis was conducted using the Kaplan-Meier Plotter website. Expression correlation analysis was performed using the Tumor Immune Estimation Resource web server. NRF1 and SPIDR expression in HCC and normal liver tissues was analyzed based on the TCGA-LIHC dataset. ChIP-qPCR was used to detect acetylation of lysine 27 on histone 3 (H3K27ac) levels of SE regions of genes, and the binding of NRF1 to the SE of SPIDR. To mimic oxidative stress, HepG2 and Hep3B cells were stimulated with H2O2. The effects of NRF1 and SPIDR on the oxidative stress response of HCC cells were determined by the functional assays.

RESULTS

A total of 318 HCC-specific SE-controlled genes were identified. The functions of these genes was significant association with oxidative stress response. SPIDR and RHOB were enriched in the "response to oxidative stress" term and were chosen for validation. SE regions of SPIDR and RHOB exhibited strong H3K27ac modification, which was significantly inhibited by JQ1. JQ1 treatment suppressed the expression of SPIDR and RHOB, and increased reactive oxygen species (ROS) levels in HCC cells. TEAD2, TEAD3, NRF1, HINFP and TCFL5 were identified as potential transcription factors for HCC-specific SE-controlled genes related to oxidative stress response. The five transcription factors were positively correlated with SPIDR expression, with the highest correlation coefficient for NRF1. NRF1 and SPIDR expression was up-regulated in HCC tissues and cells. NRF1 activated SPIDR transcription by binding to its SE. Silencing SPIDR or NRF1 significantly promoted ROS accumulation in HCC cells. Under oxidative stress, silencing SPIDR or NRF1 increased ROS, malondialdehyde (MDA) and γH2AX levels, and decreased superoxide dismutase (SOD) levels and cell proliferation of HCC cells. Furthermore, overexpression of SPIDR partially offset the effects of NRF1 silencing on ROS, MDA, SOD, γH2AX levels and cell proliferation of HCC cells.

CONCLUSION

NRF1 driven SPIDR transcription by occupying its SE, protecting HCC cells from oxidative stress-induced damage. NRF1 and SPIDR are promising biomarkers for targeting oxidative stress in the treatment of HCC.

Down regulation of NDUFS1 is involved in the progression of parenteral-nutrition-associated liver disease by increasing Oxidative stress

Parenteral nutrition (PN)-associated liver disease (PNALD) is a common and life-threatening complication of patients receiving PN. However, its definitive pathology remains unclear. Ubiquinone oxidoreductase core subunit S1 (NDUFS1), which is the largest core subunit of mitochondrial complex I, could alter the mitochondrial reactive oxygen species (ROS) formation. The purpose of this study was to investigate the role of NDUFS1 in the pathogenesis of PNALD and its underlying mechanism. We performed hepatic proteomics analysis of PNALD patients, and established a PNALD rat model to verify the role of oxidative stress, NDUFS1, pyrin inflammasome, and IL-1β in the progression of PNALD. Proteomics analysis revealed the NDUFS1 expression was decreased in PNALD patients, and the differentially espressed proteins were involved in mitochondrial respiratory chain complex Ⅰ. Treatment with MitoQ or overexpression of NDUFS1 can alleviate the progression of PNALD by reducing oxidative stress. The expression of pyrin, caspase-1, and IL-1β was increased in PN rats. Pharmacological antagonism of pyrin by colchicine can alleviate liver injury and hepatic steatosis. NDUFS1 prevents PNALD pathogenesis by regulating oxidative stress. Pyrin inflammasome and IL-1β may participate in the process of PNALD development by suppressing the transcription of MTTP and impairing the secretion of VLDL. Oxidative stress reduction may be employed as a strategy in the prevention and treatment of PNALD.

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.

Novel Strategies to Prevent Total Parenteral Nutrition-Induced Gut and Liver Inflammation, and Adverse Metabolic Outcomes

Total parenteral nutrition (TPN) is a life-saving therapy administered to millions of patients. However, it is associated with significant adverse effects, namely liver injury, risk of infections, and metabolic derangements. In this review, the underlying causes of TPN-associated adverse effects, specifically gut atrophy, dysbiosis of the intestinal microbiome, leakage of the epithelial barrier with bacterial invasion, and inflammation are first described. The role of the bile acid receptors farnesoid X receptor and Takeda G protein-coupled receptor, of pleiotropic hormones, and growth factors is highlighted, and the mechanisms of insulin resistance, namely the lack of insulinotropic and insulinomimetic signaling of gut-originating incretins as well as the potentially toxicity of phytosterols and pro-inflammatory fatty acids mainly released from soybean oil-based lipid emulsions, are discussed. Finally, novel approaches in the design of next generation lipid delivery systems are proposed. Propositions include modifying the physicochemical properties of lipid emulsions, the use of lipid emulsions generated from sustainable oils with favorable ratios of anti-inflammatory n-3 to pro-inflammatory n-6 fatty acids, beneficial adjuncts to TPN, and concomitant pharmacotherapies to mitigate TPN-associated adverse effects.

Effect of HBx on inflammation and mitochondrial oxidative stress in mouse hepatocytes

Hepatitis B virus × protein (HBx) serves an important role in the pathogenesis of the hepatitis B virus infection. Previous studies have reported that the interaction between HBx and hepatocyte mitochondria is an important factor leading to liver cell injury and apoptosis, ultimately inducing the formation of liver cancer. In the present study, a mouse model expressing HBx was constructed using hydrodynamic in vivo transfection based on the interaction between HBx and cytochrome c oxidase (COX) subunit III. The specific mechanism of HBx-induced oxidative stress in mouse hepatocytes and the subsequent effect on mitochondrial function and inflammatory injury was assessed. The results demonstrated that HBx reduced the activity of COX and the expression of superoxide dismutase and upregulated the expression of malondialdehyde, NF-κB and phospho-AKT, thus increasing oxidative stress. In addition, HBx induced an increase in interleukin (IL)-6, IL-1β and IL-18 expression levels, which created an inflammatory microenvironment in the liver, further promoting hepatocyte inflammatory injury. Therefore, it was proposed that HBx may affect hepatocyte mitochondrial respiration by reducing the activity of cytochrome c oxidase, leading to mitochondrial dysfunction and inducing hepatocyte inflammation and injury.

Mitochondrial dysfunction, apoptosis and transcriptomic alterations induced by four strobilurins in zebrafish (Danio rerio) early life stages

Though the toxicity of strobilurins on non-target aquatic organisms has been characterized, the associated toxic mechanisms have not been fully explored. The present study showed that the larval stage was the most sensitive developmental stage in zebrafish, and pyraclostrobin (PY) had the highest acute toxicity to embryos, larvae, juvenile and adult with 96 h-LC₅₀ at 0.048 mg/L, 0.029 mg/L, 0.039 mg/L, 0.031 mg/L respectively, when compared with the toxicity of trifloxystrobin (TR), kresoxim-methyl (KM) and azoxystrobin (AZ) at corresponding developmental stage. Then we investigated the transcriptomics and developmental toxicity of TR, KM, AZ and PY on zebrafish embryos after 72 h exposure. RNA-seq revealed that the pathways related to cell apoptosis and cancer, and cellular components organelle membrane and mitochondrion, were markedly affected after TR, KM, AZ and PY exposure during zebrafish early life stages. The results were further confirmed by the induction of antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD) activities, the elevation of H₂O₂, malondialdehyde (MDA) and reactive oxygen species (ROS) level, as well as the reduction of intracellular calcium ions (Ca²⁺) and mitochondrial membrane potential (MMP), which indicated that strobilurins could cause mitochondrial dysfunction and cell apoptosis. The present study was performed a systematic analysis of strobilurins to zebrafish at multi-levels, which provided suggestions for further investigation of molecular mechanisms underlying the toxicity induced by strobilurins on aquatic organisms.

Aluminum Exposure from Parenteral Nutrition: Early Bile Canaliculus Changes of the Hepatocyte

Background: Neonates on long-term parenteral nutrition (PN) may develop parenteral nutrition-associated liver disease (PNALD). Aluminum (Al) is a known contaminant of infant PN, and we hypothesize that it substantially contributes to PNALD. In this study, we aim to assess the impact of Al on hepatocytes in a piglet model. Methods: We conducted a randomized control trial using a Yucatan piglet PN model. Piglets, aged 3⁻6 days, were placed into two groups. The high Al group (n = 8) received PN with 63 µg/kg/day of Al, while the low Al group (n = 7) received PN with 24 µg/kg/day of Al. Serum samples for total bile acids (TBA) were collected over two weeks, and liver tissue was obtained at the end of the experiment. Bile canaliculus morphometry were studied by transmission electron microscopy (TEM) and ImageJ software analysis. Results: The canalicular space was smaller and the microvilli were shorter in the high Al group than in the low Al group. There was no difference in the TBA between the groups. Conclusions: Al causes structural changes in the hepatocytes despite unaltered serum bile acids. High Al in PN is associated with short microvilli, which could decrease the functional excretion area of the hepatocytes and impair bile flow.

Transglutaminase-2 is Involved in Cell Apoptosis of Osteosarcoma Cell Line U2OS Under Hypoxia Condition

Osteosarcoma is the most common type of solid bone cancer, which is the second leading cause of cancer-related death. Hypoxia is an ordinary phenomenon in solid tumor tissues and can induce cell apoptosis but the specific molecular mechanism remains unclear. In this study, we explored the effect and the molecular mechanism of Transglutaminase 2 (TG2) on cell apoptosis in osteosarcoma U2OS cells under hypoxia. We found the enzymatic activity of TG2 is significantly increased and the expression of TG2 is remarkably up-regulated under hypoxia condition. Cell apoptotic rate is markedly increased upon knockdown of TG2 by siRNA under hypoxia. We further investigated the mechanism of cell apoptosis and found Bax protein is significantly increased after depletion of TG2 under hypoxia. Moreover, our data also show that cytochrome C (Cyt C) is significantly increased in cytoplasm and markedly decreased in mitochondria of U2OS cells after depletion of TG2 under hypoxia. Our results suggest that TG2 can inhibit tumor cell apoptosis through down-regulation of Bax and prevention of release Cyt C from mitochondria into cytoplasm.

Packed red blood cell transfusions as a risk factor for parenteral nutrition associated liver disease in premature infants

AIM

To determine if packed red blood cell transfusions contribute to the development of parenteral nutrition associated liver disease.

METHODS

A retrospective chart review of 49 premature infants on parenteral nutrition for > 30 d who received packed red blood cell (PRBC) transfusions was performed. Parenteral nutrition associated liver disease was primarily defined by direct bilirubin (db) > 2.0 mg/dL. A high transfusion cohort was defined as receiving > 75 mL packed red blood cells (the median value). Kaplan-Meier plots estimated the median volume of packed red blood cells received in order to develop parenteral nutrition associated liver disease.

RESULTS

Parenteral nutritional associated liver disease (PNALD) was noted in 21 (43%) infants based on db. Among the 27 high transfusion infants, PNALD was present in 17 (64%) based on elevated direct bilirubin which was significantly greater than the low transfusion recipients. About 50% of the infants, who were transfused 101-125 mL packed red blood cells, developed PNALD based on elevation of direct bilirubin. All infants who were transfused more than 200 mL of packed red blood cells developed PNALD. Similar results were seen when using elevation of aspartate transaminase or alanine transaminase to define PNALD.

CONCLUSION

In this retrospective, pilot study there was a statistically significant correlation between the volume of PRBC transfusions received by premature infants and the development of PNALD.

p38/p53/miR-200a-3p feedback loop promotes oxidative stress-mediated liver cell death

Although our previous studies have provided evidence that oxidative stress has an essential role in total parenteral nutrition (TPN)-associated liver injury, the mechanisms involved are incompletely understood. Here, we show the existence of crosstalk between the miR-200 family of microRNAs and oxidative stress. The members of the miR-200 family are markedly enhanced in hepatic cells by hydrogen peroxide (H2O2) treatment. The upregulation of miR-200-3p in turn modulates the H2O2-mediated oxidative stress response by targeting p38α. The enhanced expression of miR-200-3p mimics p38α deficiency and promotes H2O2-induced cell death. Members of the miR-200 family that are known to inhibit the epithelial to mesenchymal transition (EMT) are induced by the tumor suppressor p53. Here, we show that p53 phosphorylation at Ser 33 contributes to H2O2-induced miR-200s transcription. In addition, we show that p38α can directly phosphorylate p53 at serine 33 upon H2O2 exposure. Thus, we suggest that in liver cells, the oxidative stress-induced, p38α-mediated phosphorylation of p53 at Ser33 is essential for the functional regulation of oxidative stress-induced miR-200 transcription by p53. Collectively, our data indicate that the p53-dependent expression of miR-200a-3p promotes cell death by inhibiting a p38/p53/miR-200 feedback loop.

Effect of an Olive Oil-Based Lipid Emulsion Compared With a Soybean Oil-Based Lipid Emulsion on Liver Chemistry and Bile Acid Composition in Preterm Infants Receiving Parenteral Nutrition: A Double-Blind, Randomized Trial

BACKGROUND

The pathogenesis of parenteral nutrition (PN)-associated liver dysfunction is multifactorial. Lipid emulsions may be one of the putative mechanisms. Our aim was to comparatively assess the effect of parenteral olive oil- and soybean oil-based lipid emulsions on liver chemistry and bile acid composition in preterm infants.

METHODS

We performed a double-blind, randomized clinical study in which 103 preterm infants were randomly assigned to PN using either soybean oil-based lipid emulsion (SO; n = 51) or olive oil (OO)-based lipid emulsion (OO; n = 52). The primary end point was liver chemistry. The secondary end point was the plasma bile acid composition.

RESULTS

One hundred infants completed this study. In the SO group, the serum direct bilirubin was significantly higher after PN for 7 days compared with the OO group. Bile acids increased over time in both treatment groups. However, specific differences in the change in bile acid composition over time were noted between groups.

CONCLUSIONS

Differences in direct bilirubin and bile acid composition were observed over time between the 2 groups. Considering the long-term use of lipid emulsions in higher risk babies, these findings might be useful for understanding the pathogenesis of PN-associated liver dysfunction.

Treatment of parenteral nutrition-associated liver disease: the role of lipid emulsions

Parenteral nutrition is a life-saving therapy for infants with intestinal failure. However, long-term parenteral nutrition carries the risk of progressive liver disease. Substantial data has implicated components of parenteral soybean oil in the pathogenesis of parenteral nutrition-associated liver disease (PNALD). Elevated serum concentrations of phytosterols, an abundance of omega-6 polyunsaturated fatty acids, and a relative paucity of α-tocopherol have been associated with the risk of cholestasis and hepatic injury observed in PNALD. Currently available treatment strategies include the reduction of the dose of administered parenteral soybean oil and/or the replacement of parenteral soybean oil with alternative parenteral lipid emulsions. The purpose of this review is to provide an overview of the pathogenetic mechanisms associated with the development of PNALD and the data evaluating currently available treatment strategies.

Mechanisms for the effects of fish oil lipid emulsions in the management of parenteral nutrition-associated liver disease

Parenteral nutrition (PN) can be life saving for infants unable to adequately absorb enteral nutrients due to intestinal failure from inadequate bowel length or function. However, long-term PN carries significant morbidity and mortality, with 30 to 60% of patients developing progressive liver dysfunction. The etiology of PN-associated liver disease (PNALD) is poorly understood, however the involvement of lipid emulsions in its pathogenesis has been clearly established, with new emphasis emerging on the role of omega-6 polyunsaturated fatty acids and omega-3 polyunsaturated fatty acids. Recent studies evaluating the use of parenteral fish oil lipid emulsions instead of soybean oil lipid emulsions have demonstrated marked improvements in cholestasis, morbidity, and mortality in patients with PNALD treated with fish oil. This review provides an overview of the role of lipid emulsions in the pathogenesis of PNALD and the proposed mechanisms by which parenteral fish oil lipid emulsions may be exerting their beneficial effects.

Glycyrrhizin represses total parenteral nutrition-associated acute liver injury in rats by suppressing endoplasmic reticulum stress

Total parenteral nutrition (TPN) is an artificial way to support daily nutritional requirements by bypassing the digestive system, but long-term TPN administration may cause severe liver dysfunction. Glycyrrhizin is an active component of licorice root that has been widely used to treat chronic hepatitis. The aim of this study is to investigate the hepatoprotective effect of glycyrrhizin on TPN-associated acute liver injury in vivo. Liver dysfunction was induced by intravenous infusion of TPN at a flow rate of 20 mL/kg/h for three h in Sprague Dawley rats. The rats were pretreated with Glycyrrhizin (1, 3 and 10 mg/kg intravenously). After receiving TPN or saline (control group) for three h, the rats were sacrificed, blood samples were collected for biochemical analyses and liver tissue was removed for histopathological and immunohistochemical examination. We found that aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (TB) and triglyceride (TG) levels were significantly increased in the TPN group without glycyrrhizin pretreatment and decreased in the glycyrrhizin-pretreated TPN group in a dose-dependent manner. The stained liver sections showed that glycyrrhizin relieved acute liver injury. The upregulation of serum protein biomarkers of reactive nitrogen species, including nitrotyrosine and inducible NO synthase (iNOS), were attenuated by glycyrrhizin pretreatment. Levels of endoplasmic reticulum (ER) stress factors, such as phosphorylation of JNK1/2, p38 MAPK and CHOP, were decreased by glycyrrhizin pretreatment. In summary, our results suggest that glycyrrhizin decreases TPN-associated acute liver injury factors by suppressing endoplasmic reticulum stress and reactive nitrogen stress.

A metabolomic analysis of two intravenous lipid emulsions in a murine model

Background

Parenteral nutrition (PN), including intravenous lipid administration, is a life-saving therapy but can be complicated by cholestasis and liver disease. The administration of intravenous soy bean oil (SO) has been associated with the development of liver disease, while the administration of intravenous fish oil (FO) has been associated with the resolution of liver disease. The biochemical mechanism of this differential effect is unclear. This study compares SO and FO lipid emulsions in a murine model of hepatic steatosis, one of the first hits in PN-associated liver disease.

Methods

We established a murine model of hepatic steatosis in which liver injury is induced by orally feeding mice a PN solution. C57BL/6J mice were randomized to receive PN alone (a high carbohydrate diet (HCD)), PN plus intravenous FO (Omegaven®; Fresenius Kabi AG, Bad Homburg VDH, Germany), PN plus intravenous SO (Intralipid®; Fresenius Kabi AG, Bad Homburg v.d.H., Germany, for Baxter Healthcare, Deerfield, IL), or a chow diet. After 19 days, liver tissue was harvested from all animals and subjected to metabolomic profiling.

Results

The administration of an oral HCD without lipid induced profound hepatic steatosis. SO was associated with macro- and microvesicular hepatic steatosis, while FO largely prevented the development of steatosis. 321 detectable compounds were identified in the metabolomic analysis. HCD induced de novo fatty acid synthesis and oxidative stress. Both FO and SO relieved some of the metabolic shift towards de novo lipogenesis, but FO offered additional advantages in terms of lipid peroxidation and the generation of inflammatory precursors.

Conclusions

Improved lipid metabolism combined with reduced oxidative stress may explain the protective effect offered by intravenous FO in vivo.

The use of fish oil lipid emulsion in the treatment of intestinal failure associated liver disease (IFALD)

Since 2004, fish oil based lipid emulsions have been used in the treatment of intestinal failure associated liver disease, with a noticeable impact on decreasing the incidence of morbidity and mortality of this often fatal condition. With this new therapy, however, different approaches have emerged as well as concerns about potential risks with using fish oil as a monotherapy. This review will discuss the experience to date with this lipid emulsion along with the rational for its use, controversies and concerns.

Hepatobiliary manifestations of gastrointestinal and nutritional disorders

Hepatobiliary manifestations of gastrointestinal and nutritional disorders can occur as part of the clinical spectrum of the underlying disease or as a consequence of the treatment of the disease. This article reviews aspects of pathogenesis, diagnosis, and management of hepatobiliary manifestations associated with a selection of gastrointestinal and nutritional disorders including inflammatory bowel disease, celiac disease, Whipple's disease, and parenteral nutrition associated disorders.

Antibiotic treatment is superior to ursodeoxycholic acid on total parenteral nutrition associated hepatic dysfunction

PURPOSE

This study aimed to investigate the apoptotic mechanisms, oxidative stress, and mechanisms of effect of antibiotics and ursodeoxycholic acid (UDCA) in total parenteral nutrition (TPN)-associated liver injury.

METHODS

Four groups of young rabbits were used in the study as follows: Group 1 (n: 7): TPN + Metronidazole (30 mg/kg IV) + Gentamicin (6 mg/kg IV); Group 2 (n: 7): TPN + UDCA (15 mg/kg per oral); Group 3 (n: 6): TPN only; and Group 4 (n: 7): Control group. After 10 days, the animals were killed and livers were removed. Hepatic apoptosis, apoptotic proteins, malondialdehyde (MDA) and myeloperoxidase (MPO) levels were studied in liver, and direct bilirubin values were assessed in the blood samples.

RESULTS

Direct bilirubin increased with TPN, and antibiotic combination, as the most effective group, significantly lowered its levels (p < 0.01). MDA values also showed significant differences in comparisons between G1 and G3 (p < 0.05) and G1-G4 (p < 0.01). An increased number of apoptotic cells was detected particularly in G2 and G3, whereas the lowest levels, other than in the control group, were found in G1. All TUNEL-positive cell number data were statistically significant except between G2 and G3(p < 0.05). Caspase-3 and Bax immunoreactivities were greatest in G2. Significant differences were shown in caspase-3 immunoreactivity between the groups (p < 0.01), except between G1 and G3 (p > 0.05). All comparisons between the groups were significant for Bax (p < 0.01). In contrast, Bcl-2 immunoreactivity was moderate and highest in G1: comparisons between G1 and the other groups demonstrated statistically significant differences (p < 0.01). Fas-L immunoreactivity was greatest in G2, and all comparisons between the groups were statistically significant (p < 0.01).

CONCLUSIONS

Metronidazole and gentamicin combination is effective on TPN-induced liver injury by the Bcl-2 anti-apoptotic pathway, total anti-apoptotic effect and by decreasing bilirubin levels. Oxidative injury in the liver increased with therapy. UDCA seems less effective on TPN-associated liver injury.

Protective effect of parenteral glutamine supplementation on hepatic function in very low birth weight infants

BACKGROUND & AIMS

Hepatic dysfunction is one of the most frequent complications of parenteral nutrition. Very low birth weight (VLBW) infants are more sensitive to liver injury due to physiological immaturity. Our studies in animals showed that glutamine supplementation could attenuate TPN-associated liver injury. The aim of study was to investigate whether parenteral glutamine supplementation can improve hepatic tolerance in VLBW infants.

METHODS

We performed a double-blind, randomized, and controlled clinical study to investigate whether parenteral glutamine supplementation can improve hepatic tolerance in VLBW infants. Thirty VLBW infants at two children's centers were randomly assigned to either a control group or a glutamine-supplemented group. The primary endpoints were hepatic function and mortality. The secondary endpoints were the time to achieve full enteral nutrition, episodes of gastric residuals, duration of parenteral nutrition, weight and head circumference gain, length of hospitalization, and days on ventilator.

RESULTS

The serum levels of aspartate aminotransferase (AST) and total bilirubin (Tbi) were decreased after PN in the glutamine-supplemented group (P < 0.05). No deaths occurred in this study. Four infants assigned to the control group and two infants in the glutamine-supplemented group were withdrawn from the study, according to intention to treat: relative risk [RR]: 1.182; 95% confidence interval [CI]: 0.937-1.490.

CONCLUSIONS

Parenteral glutamine supplementation can improve hepatic tolerance in very low birth weight infant, suggesting a hepato-protective effect.