Beneficial impact of crocetin, a carotenoid from saffron, on insulin sensitivity in fructose-fed rats

Crocetin, a unique carotenoid with potent antioxidative and anti-inflammatory activities, is a major ingredient of saffron which is used as an important spice and food colorant in various parts of the world. In the present study, the effect of crocetin on insulin resistance and its related abnormalities induced by high-fructose diet were investigated in male Wistar rats. Compared to the control rats fed on normal laboratory diet, fructose-fed rats developed a series of pathological changes including insulin resistance, hyperinsulinemia, dyslipidemia and hypertension. Although having no evident effect on the body weight, fructose feeding caused a marked increase in the weight of epididymal white adipose tissue. Furthermore, a significant reduction in the expression of both protein and mRNA of adiponectin (an insulin-sensitizing adipocytokine) was observed, whereas those of tumor necrosis factor (TNF)-alpha and leptin were enhanced in epididymal white adipose tissue in fructose-fed rats. These disorders were effectively normalized in crocetin-treated rats. Crocetin was also demonstrated here to alleviate free fatty acid (FFA)-induced insulin insensitivity and dysregulated mRNA expression of adiponectin, TNF-alpha and leptin in primary cultured rat adipocytes. These findings suggest the possibility of crocetin treatment as a preventive strategy of insulin resistance and related diseases. The favorable impact on adiponectin, TNF-alpha and leptin expression in white adipose tissue may be involved in the improvement of insulin sensitivity observed in crocetin-treated rats.     

多年生植物欧夏至草集合繁殖体特性

欧夏至草(Marrubium vulgare)为唇形科多年生植物,其扩散单元主要由集合繁殖体和种子组成,该研究以单萼筒集合繁殖体为研究材料,比较其和种子在形态特征、扩散行为及萌发特性上的差异,探讨附属物的生态功能及对可变环境的适应对策。结果表明:(1)欧夏至草集合繁殖体是具萼筒的种子,其质量远大于种子;附属物能保护种子免受机械损伤或逃避捕食者。(2)在自然生境中,欧夏至草集合繁殖体易借风力扩散到较大范围,室内扩散实验表明,静止空气中集合繁殖体比种子降落所需的时间更长、扩散能力更强;集合繁殖体是种子延迟扩散的一种适应策略,其附属物的存在与否直接导致了种子扩散能力与扩散距离的差异,支持"Alternate假说"。(3)欧夏至草集合繁殖体和种子在活力、萌发率及萌发速率方面均不存在显著差异,而吸水率远大于种子,附属物的存在是影响种子承载更多水分并更长期保留水分的重要原因;集合繁殖体内种子的萌发属随机萌发,不具有位置效应,在当季只萌发部分种子,符合间歇性萌发特性,能有效避免种群覆灭。研究表明,多年生植物其扩散单元的形态特征和萌发行为对于种群的生存重要性相对低,母株可以长期占据原有生境,保持种群个体数量,附属物的作用主要用于种群扩散。     

Ternary Blended Fullerene‐Free Polymer Solar Cells with 16.5% Efficiency Enabled with a Higher‐LUMO‐Level Acceptor to Improve Film Morphology

Ternary approaches to solar cell design utilizing a small bandgap nonfullerene acceptor as the near infrared absorber to increase the short‐circuit current density always decreases the open‐circuit voltage. Herein, a highly efficient polymer solar cell with an impressive efficiency of 16.28 ± 0.20% enabled by an effective voltage‐increased ternary blended fullerene‐free material approach is reported. In this approach, the structural similarity between the host and the higher‐LUMO‐level guest enables the two acceptors to be synergized, obtaining increased open‐circuit voltage and fill factor and a small increase of short‐circuit current density. The same beneficial effects are demonstrated by using two host binary systems. The homogeneous fine film morphologies and the π–π stacking patterns of the host blend are well maintained, while larger donor and acceptor phases and increased lamellar crystallinity, increased charge mobilities, and reduced monomolecular recombination can be achieved upon addition of the guest nonfullerene acceptor. The increased charge mobilities and reduced monomolecular recombination not only contribute to the improved fill factor but also enable the best devices to be fabricated with a relatively thicker ternary blended active layer (110 vs 100 nm). This, combined with the absorption from the added guest acceptor, contribute to the increased short‐circuit current.     

Association study of the single nucleotide polymorphisms in adiponectin-associated genes with type 2 diabetes in Han Chinese

Single-nucleotide polymorphisms （SNPs） of ADIPOQ, ADIPOR1, and ADIPOR2 have been associated with type 2 diabetes mellitus （T2DM）, but there are many conflicting results especially in Chinese populations. To investigate the contribution of the adiponectin genes and their receptors to T2DM, a case-control study was performed and 11 SNPs ofADIPOQ, ADIPOR1, and ADIPOR2 were genotyped in 985 T2DM and 1,050 control subjects, rs 16861194 （-11426 A〉G） in the putative promoter of ADIPOQ was associated with T2DM （P = 0.007; OR = 1.29, 95% CI 1.08-1.55）. None of the other 10 SNPs were associated with T2DM in this study, although rs2241766 and rs1501299 were reported to be associated with T2DM in previous Chinese studies. There was also no significant difference found from the ADIPOQ haplotype analysis, which contains rs 16861194. In addition, we also assessed potential gene-gene interactions in three genes and no interactions were found. In conclusion, our results supported the ADIPOQ gene as a possible risk factor for type 2 diabetes in Han Chinese population.     

RANKL Up-regulates Brain-type Creatine Kinase via Poly(ADP-ribose) Polymerase-1 during Osteoclastogenesis

Receptor activator of nuclear factor κB ligand (RANKL) is the key regulator for osteoclast formation and function. During osteoclastogenesis, RANKL-stimulated signals differentially modulate expression of a large number of proteins. Using proteomics approaches, we identified that brain-type cytoplasmic creatine kinase (Ckb) was greatly induced in mature osteoclasts. Ckb has been shown to contribute to osteoclast function. However, the mechanisms of Ckb regulation and the contribution of other isoforms of creatine kinase during RANKL-induced osteoclastogenesis are unknown. We found that Ckb was the predominant isoform of creatine kinase during osteoclastogenesis. Real-time PCR confirmed that RANKL induced ckb mRNA expression by over 40-fold in primary mouse bone marrow macrophages and Raw 264.7 cells. The RANKL-responsive region was identified within the −0.4- to −0.2-kb 5′-flanking region of the ckb gene. Affinity binding purification followed by mass spectrometry analysis revealed that poly(ADP-ribose) polymerase-1 (PARP-1) bound to the −0.4/−0.2-kb fragment that negatively regulated expression of ckb in response to RANKL stimulation. Electrophoretic mobility shift assays with PARP-1-specific antibody located the binding site of PARP-1 to the TTCCCA consensus sequence. The expression of PARP-1 was reduced during RANKL-induced osteoclastogenesis, concurrently with increased expression of Ckb. Consistently, knockdown of PARP-1 by lentivirus-delivered shRNA enhanced ckb mRNA expression. The activity of PARP-1 was determined to be required for its inhibitory effect on the ckb expression. In summary, we have demonstrated that PARP-1 is a negative regulator of the ckb expression. Down-regulation of PARP-1 is responsible for the up-regulation of ckb during RANKL-induced osteoclastogenesis.