Yajun Xu

Ethanol exposure induces differential microRNA and target gene expression and teratogenic effects which can be suppressed by folic acid supplementation

BACKGROUND microRNAs (miRNAs) play an important role in development and are associated with birth defects. Data are scant on the role of miRNAs in birth defects arising from exposure to environmental factors such as alcohol. METHODS In this study, we determined the expression levels of 509 mature miRNAs in fetal mouse brains with or without prenatal ethanol exposure using a miRNA microarray technique, verified by northern blot and PCR. Mouse embryos in culture were used to examine the effect of ethanol treatment on expression of the putative target genes of miR-10a (Hoxa1 and other Hox members) at mRNA and protein level. Open field and Morris water maze tests were also performed at post-natal day 35. RESULTS Ethanol treatment induced major fetal teratogenesis in mice and caused mental retardation in their offspring, namely lower locomotor activity (P < 0.01) and impaired task acquisition. Of the screened miRNAs, miR-10a, miR-10b, miR-9, miR-145, miR-30a-3p and miR-152 were up-regulated (fold change >1.5) in fetal brains with prenatal ethanol exposure, whereas miR-200a, miR-496, miR-296, miR-30e-5p, miR-362, miR-339, miR-29c and miR-154 were down-regulated (fold change <0.67). Both miR-10a and miR-10b were significantly up-regulated (P < 0.01) in brain after prenatal ethanol exposure. Ethanol treatment also caused major obstruction in the development of cultured embryos, with down-regulated Hoxa1. Co-incubation with folic acid blocked ethanol-induced teratogenesis, with up-regulated Hoxa1 and down-regulated miR-10a (P < 0.01). CONCLUSIONS The study provided new insights into the role of miRNAs and their target genes in the pathogenesis of fetal alcohol syndrome.

Effects of cod bone gelatin on bone metabolism and bone microarchitecture in ovariectomized rats

Several animal studies have showed that gelatin may be effective for minimizing bone loss in OVX rats with established osteopenia. To gain insight into how cod bone gelatin administration affects bone loss after ovariectomy, studies were carried out focusing on bone quality and the molecular mechanisms. Eighty-four female rats were ovariectomized, 12 sham-operated, divided into six groups of 12 each and treated one week after ovariectomy either with vehicle or cod bone gelatin (0.375, 0.75, 1.5, 3, 6 mg/kg body weight) for 90 days. Bone densitometry, microCT analysis, real-time PCR analysis and biochemical analysis were used at the end of the study. After 90 days, BMD of proximal tibia and femoral neck decreased in OVX rats, whereas the loss of BMD in those regions was prevented at 3 g/kg (P<0.05). However, the BMD of midshaft femurs showed no significant differences. BV/TV, Tb.N. and Tb.Th. in the 3 g/kg group were, respectively, 30.4% (P<0.05), 145.5% (P<0.05) and 81.5% (P<0.05) higher than in the OVX group. A significant decrease was detected in urine CTX, NTX and DPD, suggesting decreased bone resorption. Treatment with 3 g/kg and 6 g/kg cod bone gelatin attenuated the increase in serum IL-1beta, IL-6 and TNF-alpha observed in the OVX group. Real-time PCR showed significantly decreased levels of mRNA expression for RANKL at the dosage of 6 g/kg and the RANKL/OPG mRNA ratio in the 3 g/kg and 6 g/kg group significantly decreased compared to the OVX group (P<0.05). In conclusion, our data confirmed that the cod bone gelatin treatment at 3 g/kg is effective in the prevention of estrogen deficient bone loss by modulating the expression of RANKL and OPG and suppressing the release of proinflammatory cytokines.

Effect of folic acid on prenatal alcohol-induced modification of brain proteome in mice.

Maternal alcohol consumption during pregnancy can induce central nervous system abnormalities in the fetus, and folic acid supplementation can reverse some of the effects. The objective of the present study was to investigate prenatal alcohol exposure-induced fetal brain proteome alteration and the protective effect of folic acid using proteomic techniques. Alcohol (5.0 g/kg) was given intragastrically from gestational day (GD) 6 to 15, with or without 60.0 mg folic acid/kg given intragastrically during GD 1-16 to pregnant Balb/c mice. The control group received distilled water only. Results of litter evaluation on GD 18 showed that supplementation of folic acid reversed the prevalence of microcephaly induced by alcohol. Proteomic analysis indicated that, under the dosage of the present investigation, folic acid mainly reversed the alcohol-altered proteins involved in energy production, signal pathways and protein translation, which are all important for central nervous system development.

Effect of marine collagen peptides on long bone development in growing rats.

BACKGROUND Nutritional factors play an important role in skeletal development during growth. However, the absorption rates of many bone-related minerals are relatively low from traditional diets, especially for people in Asia and Africa. In the present study, the effect of marine collagen peptides (MCP) derived from chum salmon (Oncorhynchus keta) skin on the development of femurs in growing rats of both sexes was investigated. RESULTS MCP supplementation could increase the size, mineral density, dry weight, ash weight, content of most minerals and both stiffness and toughness of femurs in male growing rats. However, such effects were milder in female rats. The reported increase in mineral density was likely to be related to increased osteoblast activity rather than a decreased rate of bone resorption, as an increase in serum osteocalcin and bone-specific alkaline phosphatase content was observed, but no significant difference in serum N-terminal telopeptide of type I collagen compared with control was found. CONCLUSION MCP supplementation could promote the development of long bones in growing male rats.

Prevention of retinoic acid-induced early craniofacial abnormalities by folinic acid and expression of endothelin-/HAND in the branchial arches in mouse

Prevention of retinoic acid-induced craniofacial abnormalities by folinic acid, and endothelin-1 (ET-1)/dHAND protein and mRNA expression were investigated in mouse embryos using the whole embryo culture, streptavidin-biotin peroxidase complex method, and whole-mount in situ hybridization. In the whole embryo culture, 1.0 and 0.1 mm-folinic acid dose dependently prevented branchial region malformations and decreased defects by 93 % and 77 %, respectively. Folinic acid at concentrations of 1.0 and 0.1 mm significantly increased ET-1 and dHAND protein expression levels compared to retinoic acid-exposed values in embryonic branchial areas. Folinic acid also increased ET-1 and dHAND mRNA levels in the same region. The present results suggest that folinic acid may prevent retinoic acid-induced craniofacial abnormalities via increasing ET-1 and dHAND levels in the branchial region during the organogenic period.

Therapeutic actions of α-human atrial natriuretic polypeptide in 16 clinical cases

Abstract α-Human atrial natriuretic polypeptide (α-hANP) was applied to 16 clinical patients,6 patients with essential hypertension, 7 patients with congestive heart failure and 3 patients with cirrhosis. Following intravenous bolus injection of 400μg of synthetic α-hANP, a hypotensive effect of very rapid onset was found, which was more potent in the hypertensive patients than in the normotensive cases. Cardiac functions were improved significantly with a similar time course as the depressor response in the cases of heart failure or hypertension. Hemodynamic observations showed a marked increase in cardiac output, cardiac index, stroke volume, ejection fraction and ejection rate, and a concomitant decrease of the pressure in the right side of the heart and pulmonary circulation in these subjects. In addition, the renal response to α-hANP induced obvious increases in urine volume, electrolytes and creatinine excretions in all the subjects. Finally, plasma levels of aldosterone, Argvasopressin and noradrenaline were also altered by α-hANP. No significant side effects were registered. The above result confirms the therapeutic actions of α-hANP in human subjects and opens the possibility to research α-hANP as a powerful pharmacological tool as well as potential new medicine for human disorders.

Developmental Effects of Dietary Nucleotides in Second-Generation Weaned Rats

The aim of the present study was to evaluate dietary effects of dietary nucleotides (NTs) on developmental parameters in second-generation Sprague-Dawley rats. Experimental design was set up as six groups, including one control and five nucleotide administered groups, doses ranged from 0.01% to 1.28% nucleotides. First-generation (F0) rats were divided into two terms: (1) fed for 90-day study; (2) mated for offspring (F1). After weaning, each group of second-generation F1 rats was fed the control diet. Evaluating parameters were weight gain and food utilization ratios of rats, hematological and biochemical parameters, and organ pathology. The results showed that there was a greater weight gain and food utilization ratio in weaned rats (F0 and F1). Furthermore, weight gain and food utilization ratios were increased in the first 2 weeks of F1 male and the first week of F1 female rats. There were no significant changes in blood indicators of NT groups with the exception of decrease in aspartate aminotransferase and serum uric acid levels. Overall, it was demonstrated that NT supplements could promote the early growth and development at a 0.01% dose. Although NTs may have cumulative reproductive effects, they were safe even at a high-dose supplementation. Additionally, NT supplementation could promote restoration and optimize liver function.

Multi-Generations Assessment of Dietary Nucleotides Consumption in Maternal Rats

This study investigated multi-generational reproductive and developmental toxicity of dietary nucleotides (NTs) during lactation in rats with the purpose of augmenting currently available safety data. Weanling rats (F0) were fed NTs at doses of 0.01%, 0.04%, 0.16%, 0.64%, and 1.28% (wt/wt for 90 days and then mated in a 1:1 pattern. The F1 generation rats were fed NTs for 90 days after weaning. The process was repeated until F3 rats were born. We measured the physical and neural development landmarks during lactation in the F3 generation and observed the signs of maternal rats during the gestation, parturition, and lactation periods. No significant differences in either physical or neural developmental landmarks were observed between the control and NT groups. No clinically adverse effects were found in the maternal rats at any point in gestation, parturition, or lactation. There were no alterations in the indicators of parturition. No significant differences were observed between controls and NT-treated rats fed four kinds of nucleotides in F0 milk on PND 21. In conclusion, NTs in doses of up to 1.28% did not cause any adverse effects in either the maternal or filial individuals.