Research progresses on PGC-1α, a key energy metabolic regulator / 生理学报

Disturbance of the energy balance, when the energy intake exceeds its expenditure, is a major risk factor for the development of metabolic syndrome (MS). The peroxisome proliferator activated receptor γ (PPARγ) coactivator-1α (PGC-1α) functions as a key regulator of energy metabolism and has become a hotspot in current researches. PGC-1α sensitively responds to the environmental stimuli and nutrient signals, and further selectively binds to different transcription factors to regulate various physiological processes, including glucose metabolism, lipid metabolism, and circadian clock. In this review, we described the gene and protein structure of PGC-1α, and reviewed its tissue-specific function in the regulation of energy homeostasis in various mammalian metabolic organs, including liver, skeletal muscle and heart, etc. At the meanwhile, we summarized the application of potential small molecule compounds targeting PGC-1α in the treatment of metabolic diseases. This review will provide theoretical basis and potential drug targets for the treatment of metabolic diseases.

Association between S100B gene polymorphisms and hand, foot and mouth disease caused by enterovirus 71 infection / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the association between rs9722 polymorphisms in the S100B gene and hand, foot and mouth disease (HFMD) caused by enterovirus 71.</p><p><b>METHODS</b>A total of 124 HFMD children with enterovirus 71 infection were enrolled as subjects, and 56 healthy children were enrolled as control group. The rs9722 polymorphisms in the S100B gene were detected for both groups, and the serum level of S100B protein was measured for 74 HFMD children.</p><p><b>RESULTS</b>The rs9722 locus of the S100B gene had three genotypes, CC, CT, and TT, and the genotype frequencies were in accordance with Hardy-Weinberg equilibrium. Compared with the control group, the HFMD group had significant increases in the frequencies of TT genotype and T allele (P<0.01). Children with severe HFMD caused by enterovirus 71 infection had significantly higher frequencies of TT genotype and T allele than those with moderate or mild HFMD (P<0.05). Compared with the cured patients, the patients with poor prognosis had significant increases in the frequencies of TT genotype and T allele in the rs9722 locus of the S100B gene (P<0.05). Among the 74 children with HFMD, the children with TT genotype had the highest serum level of S100B protein, and those with CC genotype had the lowest level (P<0.01).</p><p><b>CONCLUSIONS</b>T allele in the rs9722 locus of the S100B gene might be a risk factor for severe HFMD caused by enterovirus 71 infection.</p>

Application value of frozen-thawed mouse round spermatids in in vitro fertilization / 中华男科学杂志

Objective@#To investigate the application value of the frozen-thawed round spermatids of the mouse in in vitro fertilization (IVF).@*METHODS@#Haploid spermatids of the mouse obtained in vitro were divided into a frozen-thawed and a fresh group and oocytes were collected from 6－8 weeks old female mice. After diamidino-phenyl-indole (DAPI) staining, the oocytes were subjected to intracytoplasmic round spermatid injection (ROSI), 259 in the frozen-thawed and 238 in the fresh group. Comparisons were made between the two groups in the capacities of fertilization and embryonic development.@*RESULTS@#The survival rate of the frozen-thawed haploid spermatids was (75.9 ± 2.3) %. No statistically significant differences were observed between the frozen-thawed and fresh groups after ROSI in the rates of fertilization (51.9 vs 55.7%, P >0.05), 2-cell embryos (51.0 vs 62.2%, P >0.05), 4－8-cell embryos (41.8 vs 42.9%, P >0.05), or morula-blastocysts (12.2 vs 21.4%, P >0.05).@*CONCLUSIONS@#Frozen-thawed round spermatids of the mouse are similar to fresh ones in their capacities of fertilization and embryonic development.

Regulation of reproduction by the circadian rhythms / 生理学报

Mammals synchronize their circadian activity primarily to the cycles of light and darkness in the environment. Circadian rhythm is controlled by the central clock in the hypothalamic suprachiasmatic nucleus (SCN) and the peripheral clocks in various tissues. More importantly, the central clock can integrate photic/nonphotic signals to generate rhythmic outputs, and then drive the slave oscillators in peripheral tissues through neuroendocrine and behavioral signals. Human reproductive activities, as some other physiological functions, are controlled by the biological clocks. Accumulating lines of epidemiological and genetic evidence indicate that disruption of circadian clock can be directly involved in multiple pathological processes, including infertility. In this review, we mainly discuss the presence of a circadian clock in reproductive tissues and its roles in follicles development, ovulation, spermatogenesis, fertilization and embryo implantation, etc. As the increased shift work and assisted reproductive technologies possibly disrupt circadian rhythmicity to impact reproduction, the importance of circadian rhythms should be highlighted in the regulation of reproductive process.

Methylation pattern of imprinted genes H19 and IGF2r in spermatogenic cells cultured in vitro / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To compare the methylation patterns of imprinting control region (ICR) of H19 gene and differentially methylated region (DMR) of IGF2r gene in mature sperms derived from epididymis of Kunming mice and in vitro cultured haploid spermatids.</p><p><b>METHODS</b>The H19 ICR and IGF2r DMR2 were detected by bisulfite sequencing PCR (BSP). The results were compared with standard sequence derived from GenBank using a DNAman software.</p><p><b>RESULTS</b>96.67% (15 CpG sites) of H19 ICR was found to be methylated, and 94.29% IGF2r DMR2 was found to be unmethylated in mature sperms. By contrast, 69.33% of H19 ICR and 44.29% of IGF2r DMR2 were found to be methylated in the haploid spermatids cultured in vitro. A significant difference was detected in the methylation patterns between the two types of cells (P<0.01).</p><p><b>CONCLUSION</b>The H19 ICR in mature sperm of Kunming mice was essentially methylated, while the IGF2r DMR2 was essentially unmethylated. Partial methylation loss in H19 ICR and abnormal methylation in IGF2r DMR2 were found in the haploid spermatids cultured in vitro.</p>