Triptolide prevents bone loss via suppressing osteoclastogenesis through inhibiting PI3K-AKT-NFATc1 pathway

Bone loss (osteopenia) is a common complication in human solid tumour. In addition, after surgical treatment of gynaecological tumour, osteoporosis often occurs due to the withdrawal of oestrogen. The major characteristic of osteoporosis is the low bone mass with micro-architectural deteriorated bone tissue. And the main cause is the overactivation of osteoclastogenesis, which is one of the most important therapeutic targets. Inflammation could induce the interaction of RANKL/RANK, which is the promoter of osteoclastogenesis. Triptolide is derived from the traditional Chinese herb lei gong teng, presented multiple biological effects, including anti-cancer, anti-inflammation and immunosuppression. We hypothesized that triptolide could inhibits osteoclastogenesis by suppressing inflammation activation. In this study, we confirmed that triptolide could suppress RANKL-induced osteoclastogenesis in bone marrow mononuclear cells (BMMCs) and RAW264.7 cells and inhibited the osteoclast bone resorption functions. PI3K-AKT-NFATc1 pathway is one of the most important downstream pathways of RANKL-induced osteogenesis. The experiments in vitro indicated that triptolide suppresses the activation of PI3K-AKT-NFATc1 pathway and the target point located at the upstream of AKT because both NFATc1 overexpression and AKT phosphorylation could ameliorate the triptolide suppression effects. The expression of MDM2 was elevated, which demonstrated the MDM-p53-induced cell death might contribute to the osteoclastogenesis suppression. Ovariectomy-induced bone loss and inflammation activation were also found to be ameliorated in the experiments in vivo. In summary, the new effect of anti-cancer drug triptolide was demonstrated to be anti-osteoclastogenesis, and we demonstrated triptolide might be a promising therapy for bone loss caused by tumour.     

VPS13D interacts with VCP/p97 and negatively regulates endoplasmic reticulum–mitochondria interactions

Membrane contact sites (MCSs) between the endoplasmic reticulum (ER) and mitochondria are emerging as critical hubs for diverse cellular events, and alterations in the extent of these contacts are linked to neurodegenerative diseases. However, the mechanisms that control ER–mitochondria interactions are so far elusive. Here, we demonstrate a key role of vacuolar protein sorting–associated protein 13D (VPS13D) in the negative regulation of ER–mitochondria MCSs. VPS13D suppression results in extensive ER–mitochondria tethering, a phenotype that can be substantially rescued by suppression of the tethering proteins VAPB and PTPIP51. VPS13D interacts with valosin-containing protein (VCP/p97) to control the level of ER-resident VAPB at contacts. VPS13D is required for the stability of p97. Functionally, VPS13D suppression leads to severe defects in mitochondrial morphology, mitochondrial cellular distribution, and mitochondrial DNA synthesis. Together, our results suggest that VPS13D negatively regulates the ER–mitochondria MCSs, partially through its interactions with VCP/p97.     

层粘连蛋白与顺铂对腹水肝癌细胞内微丝的共同作用关系

本文探讨在外源性层粘连蛋白与抗癌药物顺铂的共同作用下,癌细胞内微丝组装的变化。结果发现外源性层粘连蛋白与小鼠腹水型肝癌细胞膜受体结合后,促进肌动蛋白微丝组装,使其含量增加;而多靶性抗癌药物顺铂与肌动蛋白微丝的结合,抑制微丝组装过程,造成微丝含量减少;两种试剂共同作用于癌细胞时,肌动蛋白微丝的含量与对照组相比非常接近。本研究为上述两种物质对癌细胞内微丝组装的拮抗性作用提出直接证据。     

盆底肌功能训练联合阴茎夹对前列腺增生术后患者尿失禁的临床应用分析

目的:分析盆底肌功能训练联合阴茎夹对前列腺增生术后患者尿失禁的临床应用效果。方法:选取我院2017年4月～2019年4月收治的72例前列腺增生术后尿失禁患者,随机分为对照组和观察组各36例,两组均予盆底肌功能训练,观察组加用阴茎夹控制排尿。对比两组术后尿失禁改善情况、排尿改善情况、国际尿失禁咨询委员会尿失禁问卷表简表(ICI-Q-SF)评分变化、压力性尿失禁分度评价及经济费用情况。结果:两组干预后20 d、干预后30 d、干预后90 d尿失禁发生率均较干预后10 d下降,观察组干预后10 d、干预后20 d、干预后30 d、干预后90 d尿失禁发生率均低于对照组,差异均有统计学意义(P0.05)。两组干预后90 d每日总尿量较干预前升高,每日总排尿次数、每日总漏尿次数均较干预前下降;观察组干预后90 d每日总尿量高于对照组,每日总排尿次数、每日总漏尿次数均低于对照组,差异均有统计学意义(P0.05)。两组干预后90d ICI-Q-SF评分均较干预前下降,且观察组干预后90d ICI-Q-SF评分低于对照组,差异均有统计学意义(P0.05)。观察组患者干预后压力性尿失禁临床治愈率高于对照组,差异有统计学意义(P0.05)。两组患者压力性尿失禁分度情况比较差异无统计学意义(P0.05)。观察组阴茎夹使用费用为(70.26±8.51)元,低于对照组的(388.71±26.44)元,差异有统计学意义(P0.05)。结论:在盆底肌功能训练的基础上联合阴茎夹能够有效改善前列腺增生术后患者尿失禁症状及生活质量,且有助于降低患者经济负担,值得临床推广应用。     

新工科背景下生物反应工程课程的多元化教学模式改革与探索

生物反应工程作为一门理论性与应用性都很强的专业课程,在生物工程等相关专业的课程设置中处于桥梁和纽带地位,对新型应用型工科人才的培养发挥着重要的作用.但由于该课程中公式等抽象理论知识过多,导致学生学习效率十分低下.因此,为了适应新工科教育背景下对创新型人才培养的需求,提高学生的学习兴趣和积极性,并培养学生的自主学习等创新...     

IL-17A injury to retinal ganglion cells is mediated by retinal Müller cells in diabetic retinopathy

Diabetic retinopathy (DR), the most common and serious ocular complication, recently has been perceived as a neurovascular inflammatory disease. However, role of adaptive immune inflammation driven by T lymphocytes in DR is not yet well elucidated. Therefore, this study aimed to clarify the role of interleukin (IL)-17A, a proinflammatory cytokine mainly produced by T lymphocytes, in retinal pathophysiology particularly in retinal neuronal death during DR process. Ins2^Akita (Akita) diabetic mice 12 weeks after the onset of diabetes were used as a DR model. IL-17A-deficient diabetic mice were obtained by hybridization of IL-17A-knockout (IL-17A-KO) mouse with Akita mouse. Primarily cultured retinal Müller cells (RMCs) and retinal ganglion cells (RGCs) were treated with IL-17A in high-glucose (HG) condition. A transwell coculture of RGCs and RMCs whose IL-17 receptor A (IL-17RA) gene had been silenced with IL-17RA-shRNA was exposed to IL-17A in HG condition and the cocultured RGCs were assessed on their survival. Diabetic mice manifested increased retinal microvascular lesions, RMC activation and dysfunction, as well as RGC apoptosis. IL-17A-KO diabetic mice showed reduced retinal microvascular impairments, RMC abnormalities, and RGC apoptosis compared with diabetic mice. RMCs expressed IL-17RA. IL-17A exacerbated HG-induced RMC activation and dysfunction in vitro and silencing IL-17RA gene in RMCs abolished the IL-17A deleterious effects. In contrast, RGCs did not express IL-17RA and IL-17A did not further alter HG-induced RGC death. Notably, IL-17A aggravated HG-induced RGC death in the presence of intact RMCs but not in the presence of RMCs in which IL-17RA gene had been knocked down. These findings establish that IL-17A is actively involved in DR pathophysiology and particularly by RMC mediation it promotes RGC death. Collectively, we propose that antagonizing IL-17RA on RMCs may prevent retinal neuronal death and thereby slow down DR progression.Subject terms: Cell death, Medical research     

Molecular mechanisms underlying function of hair bundle: study on genetic deafness in mouse models

Although the basic principles for the function of peripheral auditory system have been known for many years, the molecular mechanisms which affect deafness are not clear. In recent years, the study of hereditary deafness associated mouse models has revealed the molecular basis which is related with the formation and function of the hair bundle and the mechanosensory organelle of hair cell. This review focused on the role of protein network, which is formed by the proteins encoded by the Usher syndrome type 1 genes, in hair-bundle development and mechanotransducer channel gating. And the review also showed how the stereocilia rootlets contribute to the hair bundle's mechanical properties and how the hair bundle produces suppressive masking. Finally, the review revealed multiple roles of the tectorial membrane and extracellular matrix in the hair bundles stimulating in the cochlea.     

A new strategy employed for identification of sweet orange cultivars with RAPD markers

We optimized RAPD techniques by increasing the length of RAPD primers and performing a strict screening of PCR annealing temperature to distinguish 60 sweet orange cultivars from the Research Institute of Pomology at the Chinese Academy of Agricultural Sciences. A new approach called cultivar identification diagram (CID) was used to improve the efficiency of RAPD markers for cultivar identification. Thirteen effective primers were first screened from 54 RAPD arbitrary 11-mer primers based on their amplification products and amplified polymorphic bands; they were then used for PCR amplification of all 60 cultivars. All cultivars were manually and completely separated by the polymorphic bands appearing in DNA fingerprints from 13 primers; a CID of the 60 sweet orange cultivars was then constructed. This CID separated all the cultivars from each other, based on the polymorphic bands; the corresponding primers were marked in the correct positions on the sweet orange CID. The CID strategy facilitates the identification of fruit cultivars with DNA markers. This CID of sweet orange cultivars will be very useful for the protection of cultivar rights and for early identification of seedlings in the nursery industry.     

Preparations of meiotic pachytene chromosomes and extended DNA fibers from cotton suitable for fluorescence in situ hybridization

Fluorescence in situ hybridization (FISH) has become one of the most important techniques applied in plant molecular cytogenetics. However, the application of this technique in cotton has lagged behind because of difficulties in chromosome preparation. The focus of this article was FISH performed not only on cotton pachytene chromosomes, but also on cotton extended DNA fibers. The cotton pollen mother cells (PMCs) instead of buds or anthers were directly digested in enzyme to completely breakdown the cell wall. Before the routine acetic acid treatment, PMCs were incubated in acetic acid and enzyme mixture to remove the cytoplasm and clear the background. The method of ice-cold Carnoy's solution spreading chromosome was adopted instead of nitrogen removed method to avoid chromosomes losing and fully stretch chromosome. With the above-improved steps, the high-quality well-differentiated pachytene chromosomes with clear background were obtained. FISH results demonstrated that a mature protocol of cotton pachytene chromosomes preparation was presented. Intact and no debris cotton nuclei were obtained by chopping from etiolation cotyledons instead of the conventional liquid nitrogen grinding method. After incubating the nuclei with nucleus lysis buffer on slide, the parallel and clear background DNA fibers were acquired along the slide. This method overcomes the twist, accumulation and fracture of DNA fibers compared with other methods. The entire process of DNA fibers preparation requires only 30 min, in contrast, it takes 3 h with routine nitrogen grinding method. The poisonous mercaptoethanol in nucleus lysis buffer is replaced by nonpoisonous dithiothreitol. PVP40 in nucleus isolation buffer is used to prevent oxidation. The probability of success in isolating nuclei for DNA fiber preparation is almost 100% tested with this method in cotton. So a rapid, safe, and efficient method for the preparation of cotton extended DNA fibers suitable for FISH was established.