Deficiency or activation of peroxisome proliferator-activated receptor α reduces the tissue concentrations of endogenously synthesized docosahexaenoic acid in C57BL/6J mice

BACKGROUND/OBJECTIVES: Docosahexaenoic acid (DHA), an n-3 long chain polyunsaturated fatty acid (LCPUFA), is acquired by dietary intake or the in vivo conversion of α-linolenic acid. Many enzymes participating in LCPUFA synthesis are regulated by peroxisome proliferator-activated receptor alpha (PPARα). Therefore, it was hypothesized that the tissue accretion of endogenously synthesized DHA could be modified by PPARα. MATERIALS/METHODS: The tissue DHA concentrations and mRNA levels of genes participating in DHA biosynthesis were compared among PPARα homozygous (KO), heterozygous (HZ), and wild type (WT) mice (Exp I), and between WT mice treated with clofibrate (PPARα agonist) or those not treated (Exp II). In ExpII, the expression levels of the proteins associated with DHA function in the brain cortex and retina were also measured. An n3-PUFA depleted/replenished regimen was applied to mitigate the confounding effects of maternal DHA. RESULTS: PPARα ablation reduced the hepatic Acox, Fads1, and Fads2 mRNA levels, as well as the DHA concentration in the liver, but not in the brain cortex. In contrast, PPARα activation increased hepatic Acox, Fads1, Fads2 and Elovl5 mRNA levels, but reduced the DHA concentrations in the liver, retina, and phospholipid of brain cortex, and decreased mRNA and protein levels of the brain-derived neurotrophic factor in brain cortex. CONCLUSIONS: LCPUFA enzyme expression was altered by PPARα. Either PPARα deficiency or activation-decreased tissue DHA concentration is a stimulus for further studies to determine the functional significance.

Lactose intolerance in neonates with non-infectious diarrhea / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the development of lactose intolerance in neonates with non-infectious diarrhea and its association with diarrhea, and to evaluate the diagnostic values of fecal pH value and urine galactose determination for neonatal lactase deficiency.</p><p><b>METHODS</b>Seventy hospitalized neonates who developed non-infectious diarrhea between October 2012 and June 2015 were enrolled as the diarrhea group, and 162 hospitalized neonates without non-infectious diarrhea were enrolled as the non-diarrhea group. Test paper was used to determine fecal pH value. The galactose oxidase method was used to detect urine galactose. The neonates with positive galactose oxidase were diagnosed with lactase deficiency, and those with lactase deficiency and diarrhea were diagnosed with lactose intolerance. According to the results of urine galactose detection, 69 neonates in the diarrhea group who underwent urine galactose detection were classified into lactose intolerance group (45 neonates) and lactose tolerance group (24 neonates), and their conditions after treatment were compared between the two groups. The follow-up visits were performed for neonates with diarrhea at 3 months after discharge.</p><p><b>RESULTS</b>Fecal pH value and positive rate of urine galactose (65% vs 54%) showed no significant differences between the diarrhea and non-diarrhea groups (P>0.05). Fecal pH value showed no significant difference between the lactose intolerance and lactose tolerance groups (P>0.05), while the neonates in the lactose intolerance group had a significantly longer time to recovery of defecation than those in the lactose tolerance group (P<0.05).</p><p><b>CONCLUSIONS</b>The incidence of lactase deficiency is high in neonates, and diarrhea due to lactose intolerance tends to occur. Determination of fecal pH value has no significance in the diagnosis of lactose intolerance in neonates with diarrhea.</p>

Expression and significance of insulin-like growth factor-1 and insulin-like growth factor binding protein-3 in hepatocyte steatosis model / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the expression of IGF-1 and IGFBP-3 in nonalcoholic fatty steatosis hepatocyte models induced by oleic acid.</p><p><b>METHOD</b>Nonalcoholic fatty steatosis hepatocyte models induced by oleic acid on immortalized human hepatocyte, Oil red O staining and intracellular triglycerides were detected for observing the situation of IHH cells fatty degeneration. IHH cells were divided into control group, NAFLD group, which the control group cultured in DMEM/F12 medium, NAFLD group were treated with oleic acid, 0.5 mmol/L treatment for 72 h. The expression of mRNA and protein of IGF-1 and IGFBP3 were measured by immunofluorescent staining, Western blot and RT-PCR methods. Between the two groups were compared using the t- test.</p><p><b>RESULTS</b>The steatosis models of the hepatocytes were established successfully with 0.5 mmol/L oleic acid. Lipid droplets were observed through Oil red O staining. The level of hepatocyte TG was increased (275.7+/-27.2) mug/mg from (150.2+/-15.6) mug/mg (t = 21.67, P less than 0.01). Compared with the control group, the mRNA of IGF-1 (0.76+/-0.04 vs 4.82+/-1.51, t = 17.915, P less than 0.01), IGFBP-3 (1.58+/-0.93 vs 5.41+/-1.37, t = 12.893, P less than 0.01) and protein expression of IGF-1 (1.00+/-0.29 vs 2.56+/-0.71, t = 29.17, P less than 0.01), IGFBP-3 (0.65+/-0.36 vs 1.23+/-0.91, t = 32. 12, P less than 0.01) significantly decreased in oleic acid-treated group. The results of immunofluorescence staining also confirm the significantly decreased protein expression of IGF-1 and IGFBP-3 in NAFLD group compared with control group.</p><p><b>CONCLUSION</b>The expression of IGF-1 and IGFBP-3 decreased in nonalcoholic fatty steatosis hepatocyte models, which will provide the experimental basis for the further study of the mechanism of the limited height of some children with non-alcoholic fatty liver disease in clinical.</p>

Metabolic characteristics of a fatty liver disease model induced by high-fat feeding in young rats / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To establish nonalcoholic fatty liver disease (NAFLD) in young rats, and to investigate the metabolic characteristics of these rats.</p><p><b>METHODS</b>Fifteen male and fifteen female SD rats of 3 weeks old were randomly divided into three groups, normal group (N), 20% high fat group (HF1) and 30% high fat group (HF2). All the rats were fed under Specific pathogen Free (SPF) condition for 6 weeks and executed at the end of the 6th week. Body length and weight of each rat as well as their liver weight were measured for calculating Liver Index (LI). ALT, AST, TG, TC, INS, Glu and HOMA-IR in the blood were measured. Liver tissue homogenate was prepared for detecting TG level. The liver section was stained with HE and oil red. The expression of SPEBP-1 and leptin in liver was detected by immunostaining.</p><p><b>RESULTS</b>The typical pathological change of NAFLD was found in the rats of HF groups. In HF2 group, no rats died during the experiment and the degree of fat degeneration is homogeneous. Comparing with those in N group, TC (mmol/L), liver TG (mmol/L) and ALT levels in HF2 group were significantly elevated (2.50+/-0.39 vs 1.82+/-0.43, P less than 0.01; 25.38+/-13.29 vs 12.09+/-9.59, P less than 0.01 and 69.80+/-18.22 vs 48.00+/-10.45, P less than 0.01, respectively). Comparing with those in N group, TG level in HF1 group was significantly decreased (0.17+/-0.10 vs 0.32+/-0.12, P less than 0.05), Glu level in HF1 group was significantly elevated (12.33+/-3.48 vs 8.13+/-2.53, P less than 0.05). There were no significant difference between the results of AST, INS and HOMA-IR among the groups. The expression level of SREBP-1 and leptin increased in HF groups.</p><p><b>CONCLUSION</b>NAFLD can be induced by 30% high-fat feeding for 6 weeks in young rats, high-fat feeding induces the expression of SREBP-1 and leptin expression and fat synthesis.</p>

Analysis of High Risk Factors for Metabolic Syndrome in Obese Children with Acanthosis Nigricans / 实用儿科临床杂志

Objective To explore the high risk factors of metabolic syndrome(MS) in obese children with acanthosis nigricans.Me-thods Body mass index(BMI),blood lipid including triglyeride(TG) and cholesterol(CHO),low density lipoprotein-cholesterol(LDL-C),blood pressure,the level of fasting blood glucose(FBG) and 2 h after oral glucose tolerance test blood glucose(OGTT 2h BG) and the level of fasting insulin(FINS) and 2 h after oral glucose tolerance test insulin (OGTT 2h INS) and homeostasis model appraisal insulin resis-tance index(HOMA-IR) were measured and compared between 25 obese children with acanthosis nigricans[male 15,female 10;aged 8.4-16.0,mean 10.6 years old,weight (72.11?17.66) kg;height (155?14) cm]and 32 normal healthy children[male 18,female 14;aged 7.6-15.8,mean 9.8 years old]in department of pediatric during 1 year.HOMA-IR were also analyzed.Ultrasonic inspections for liver were performed in those children.Results BMI,TG,LDL-C and blood pressure in the obese group were significantly higher than those in the normal control group(Pa0.05).Eighty-four percent of patients in obese children with acanthosis nigricans were diagnosed adiposis hepatica by ultrasonograph.Conclusions The increasing BMI,insulin resistance,blood lipid disorder and blood pressure increase in obese children with acanthosis nigricans are the high risk factors of MS,the close followed-up and treating this kind of obese children can acquire MS early and be helpful to postpone the progress of diabetesⅡ and cardiovascular diseases.