Artesunate negatively controls expression of cyclin D1 and activity of AP-1 by inhibiting the activation of ERK1/2 protein in HSC-T6 cells

AIM: To investigate the effects of artesunate(Art) on the expression of ERK1/2, AP-1 and cyclin D1 in rat hepatic stellate cells (HSCs), and to elucidate the molecular mechanism of Art against hepatic fibrosis. METHODS: HSC-T6 cells were treated with platelet-derived growth factor BB(PDGF-BB) to induce cell proliferation. The cells were divided into control group, PDGF-BB group, PDGF-BB+Art groups (with 6.25 mg稬^-1, 25 mg稬^-1or 50 mg稬^-1 of Art) and PDGF-BB+PD98059 group. The level of collagen type I in the supernatant was detected by enzyme-linked immunosorbent assay (ELISA). The mRNA expression levels of ERK1/2 and cyclin D1 were measured by RT-PCR. The protein levels of p-ERK1/2 and cyclin D1 in HSC-T6 cells were detected by Western blotting. The activity of AP-1 was analyzed by electrophoretic mobility shift assay. RESULTS: The concentration of collagen type I was significantly higher in PDGF-BB group than that in control group (P<0.05), and decreased in PDGF-BB+Art group and PDGF-BB+PD98059 group in comparison with that in PDGF-BB group (P<0.05, P<0.01). The protein level of ERK1/2 in PDGF-BB+Art group (50 mg稬^-1) was lower than that in PDGF-BB group (P<0.05), and was even lower in PDGF-BB+PD98059 group (P<0.01). The mRNA expression of cyclin D1 in PDGF-BB+Art groups (25 mg稬^-1and 50 mg稬^-1) and PDGF-BB+PD98059 group were significantly lower than that in PDGF-BB group (P<0.05). The protein levels of p-ERK1/2 and cyclinD1 were the highest in PDGF-BB group, and significantly lower in PDGF-BB+Art groups (6.25 mg稬^-1, 25 mg稬^-1 and 50 mg稬^-1) and PDGF-BB+PD98059 group (P<0.05, P<0.01). The AP-1 binding activity in HSC-T6 cells was down-regulated by Art. CONCLUSION: Artesunate inhibits the proliferation of HSC-T6 cells in vitro by inhibiting the activation of ERK1/2, thus down-regulating the activity of AP-1 and expression of cyclin D1.     

Echinacoside promotes bone regeneration by increasing OPG/RANKL ratio in MC3T3-E1 cells

Echinacoside (ECH), isolated from Cistanche tubulosa (Schrenk) R. Wight stems, was subjected to in vitro experiments to investigate its bioactivities on proliferation, differentiation and mineralization of the osteoblastic cell line MC3T3-E1. MTT assay, the alkaline phosphatase (ALP) activity and calcium deposition were determined, and the secretion of collagen I (COL I), osteocalcin (OCN), osteoprotegerin (OPG) and receptor activator of nuclear factor-κB ligand (RANKL) were also assayed by enzyme-linked immunosorbent assay (ELISA). The results showed that ECH caused a significant increase in cell proliferation, ALP activity, COL I contents, OCN levels and an enhancement of mineralization in osteoblasts at the concentration range from 0.01 to 10 nmol·L^− 1 (p < 0.05), suggesting that ECH has a stimulatory effect on osteoblastic bone formation or has potential activity against osteoporosis. In addition, the ratio of OPG/RANKL also could be enhanced by ECH. These findings provide the potent evidence that ECH can promote bone regeneration in cultured osteoblastic MC3T3-E1 cells, which might be done by elevating the OPG/RANKL ratio, and potential evidence for echinacoside to be a promising drug or a lead compound in the development of disease-modifying drug to prevent osteoporosis.     

Time-dependent changes of calbindin D-28K and parvalbumin immunoreactivity in the hippocampus of rats with streptozotocin-induced type 1 diabetes

The hippocampus is affected by various stimuli that include hyperglycemia, depression, and ischemia. Calcium-binding proteins (CaBPs) have protective roles in the response to such stimuli. However, little is known about the expression of CaBPs under diabetic conditions. This study was conducted to examine alterations in the physiological parameters with type 1 diabetes induced with streptozotocin (STZ) as well as time-dependent changes in the expression of two CaBPs changes of were being evaluated. Rats treated with STZ (70 mg/kg) had high blood glucose levels (>21.4 mmol/L) along with increased food intake and water consumption volumes compared to the sham controls. In contrast, body weight of the animals treated with STZ was significantly reduced compared to the sham group. CB-specific immunoreactivity was generally increased in the hippocampal CA1 region and granule cell layer of the dentate gyrus (DG) 2 weeks after STZ treatment, but decreased thereafter in these regions. In contrast, the number of PV-immunoreactive neurons and fibers was unchanged in the hippocampus and DG 2 weeks after STZ treatment. However, this number subsequently decreased over time. These results suggest that CB and PV expression is lowest 3 weeks after STZ administration, and these deficits lead to disturbances in calcium homeostasis.     

Effects of photoperiod on secretory patterns of growth hormone in adult male goats

The aim of the present study was to clarify the effect of photoperiod on secretory patterns of growth hormone (GH) in male goats. Adult male goats were kept at 20°C with an 8‐h or 16‐h light photoperiod, and secretory patterns of GH secretion were compared. In addition, plasma profiles of prolactin (PRL), insulin‐like growth factor‐I (IGF‐I) and testosterone (T) were also examined to characterize GH secretion. GH was secreted in a pulsatile manner. There was no significant difference in pulse frequency between the 8‐h and 16‐h photoperiods. However, GH pulse amplitude tended to be greater in the group with the 16‐h photoperiod (P = 0.1), and mean GH concentrations were significantly greater in the 16‐h photoperiod (P < 0.05). The GH‐releasing response to GH releasing hormone was greater in the 16‐h than 8‐h photoperiod (P < 0.05). Plasma PRL and IGF‐I levels were higher in the 16‐h than 8‐h photoperiod (P < 0.05). In contrast, plasma T levels were lower in the 16‐h photoperiod (P < 0.05). These results show that a long light photoperiod enhances the secretion of GH as well as PRL and IGF‐I, but reduces plasma T concentrations in male goats.     

赤羽病SYBR Green I实时荧光PCR方法的建立和应用

本研究根据赤羽病毒（AKAV）的S基因序列设计合成了引物, RT-PCR扩增得到目的基因片段并克隆到PGM-T载体得到质粒标准品。通过对荧光定量PCR反应条件的优化,建立了SYBR Green I荧光定量PCR检测AKAV的方法。该方法的检测敏感性达到926拷贝/25μL,并具有较好的重复性和特异性。本试验方法的建立对于加强进出口牛AKAV的检验检疫具有十分重要的意义。     

鸭源致病性大肠杆菌工型菌毛pilA基因序列测定及生物信息学分析

据GenBank中人源大肠杆菌pilA基因序列，由Oligo 6．0设计一对引物，以提取的鸭源致病性大肠杆菌基因组为模板，进行PCR扩增，获得了5株鸭源致病性大肠杆菌的pilA基因，序列测定和生物信息学分析表明：鸭源致病性大肠杆菌pilA基因核苷酸序列长度为549bp，编码182aa，与人源、鸡源及猪源大肠杆菌pilA基因之间核苷酸同源性为87．3％～100．0％，氨基酸同源性为87．5％～100．0％。对不同宿主来源大肠杆菌pilA基因所编码蛋白的二级结构、亲水性、抗原性、抗原表位进行预测分析比较，结果显示Ⅰ型菌毛间具有一定的结构相似性，并存在一定的共同抗原位点；系统进化分析表明，各菌株之间的pilA基因遗传相关性与其宿主来源及血清型之间没有严格的相关性。     

淹水胁迫对菘蓝苗期乙醇脱氢酶与过氧化物酶活性的影响

目的:研究淹水胁迫下菘蓝中乙醇脱氢酶(ADH)和过氧化物酶(Peroxidase,POD)活性的变化,以期为进一步研究菘蓝抗涝害的机理提供参考.方法:应用NAD还原法测定淹水胁迫下菘蓝中乙醇脱氢酶活性的变化;采用愈创木酚比色法测定过氧化物酶活性.结果:淹水胁迫下乙醇脱氢酶活性被诱导,淹水处理不同时间乙醇脱氢酶活性均高于...     

不同寄主植物上茶黄硬蓟马mtDNACOⅠ序列分析

采用线粒体DNACOⅠ基因片段作为分子标记,对11个不同寄主上的茶黄硬蓟马(Scirtothrips dorsalis Hood)进行系统发育研究,获得655bp的线粒体DNACOⅠ基因片段。序列分析结果表明,不同寄主上茶黄硬蓟马mtDNACOⅠ的遗传距离在0~0.046之间,平均遗传距离为0.012。其中遗传距离最大的是木棉,遗传距离为0.046;杧果、荔枝、鳄梨、番荔枝、龙眼、咖啡无差异,遗传距离为0。基于COⅠ构建的11种寄主上茶黄硬蓟马之间的系统发育MP树显示:杧果、荔枝、鳄梨、番荔枝、龙眼、咖啡、花生、茶树紧密的聚合在一起;辣椒、台湾相思、木棉各为一支。     

Digestibility of protein and starch from sorghum (Sorghum bicolor) is linked to biochemical and structural features of grain endosperm

Although a principal source of energy and protein for millions of the world's poorest people, the nutritional value of sorghum (Sorghum bicolor L. Moench) is diminished because of low digestibility of grain protein and starch. To address this problem, we analyzed the properties of two sorghum lines that have a common pedigree but differ in digestibility. Consistent with results based on a ruminal fluid assay, the protein and starch of one line (KS48) was more thoroughly digested than that of the other (KS51) using in vitro assays based on pepsin and α-amylase. The indigestibility of KS51 relative to KS48 was shown to be due to (i) a greater abundance of disulfide-bonded proteins; (ii) presence in KS51 of non-waxy starch and the accompanying granule-bound starch synthase; and (iii) the differing nature of the protein matrix and its interaction with starch. The current findings suggest that each of these factors should be considered in efforts to enhance the nutritional value of sorghum grain.