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31.
Introduction: Mitochondrial-derived peptides (MDPs) are encoded within the mitochondrial genome. They signal within the cell or are released to act as autocrine/paracrine/endocrine cytoprotective factors playing a key role in the cellular stress response. The first reported and better characterized MDP is humanin (HN), which exerts robust protective effects against a myriad of cytotoxic stimuli in many cell types. These effects have led to the evaluation of HN and its analogs as therapeutic targets for several chronic diseases.

Areas covered: We describe the latest findings on the mechanism of action of HN and discuss the role of HN as therapeutic target for neurodegenerative and cardiovascular diseases, diabetes, male infertility, and cancer. Since HN can be detected in circulation, we also depict its value as a biomarker for these diseases.

Expert opinion: HN analogs and peptide mimetics have been developed over the last decade and show promising results in preclinical models of degenerative diseases. Local administration of gene therapy vectors that overexpress or silence endogenous HN could also hold therapeutic potential. Controversy on the role of HN in cancer progression and chemoresistance should be addressed before the translation of these therapeutic approaches.  相似文献   

32.
Seropositivity for HSV reaches more than 70% within the world population, and yet no approved vaccine exists. While HSV1 is responsible for keratitis, encephalitis, and labialis, HSV2 carriers have a high susceptibility to other STD infections, such as HIV. Induction of antiviral innate immune responses upon infection depends on a family of pattern recognition receptors called Toll‐like receptors (TLR). TLRs bridge innate and adaptive immunity by sensing virus infection and activating antiviral immune responses. HSV adopts smart tricks to evade innate immunity and can also manipulate TLR signaling to evade the immune system or even confer destructive effects in favor of virus replication. Here, we review mechanisms by which HSV can trick TLR signaling to impair innate immunity. Then, we analyze the role of HSV‐mediated molecular cues, in particular, NF‐κB signaling, in promoting protective versus destructive effects of TLRs. Finally, TLR‐based therapeutic opportunities with the goal of preventing or treating HSV infection will be discussed.  相似文献   
33.
目的 利用网络药理学分析康莱特注射液3种主要成分的抗肿瘤作用机制。方法 以康莱特注射液中具有抗肿瘤作用的甘油三油酸酯、薏苡仁酯、薏苡素为研究对象,依托中药系统药理学数据库(TCMSP)、反向分子对接服务器(PharmMapper)、人类基因组注释数据库(GeneCards)、药物治疗靶标数据库(TTD)进行靶点预测和筛选,借助Cytoscape 3.5.1软件构建活性成分-靶点-疾病网络,借助STRING平台构建靶蛋白相互作用网络,通过DAVID平台对靶点基因本位生物过程和KEGG信号通路进行富集分析。结果 康莱特注射液活性成分作用于EGFR、PGR、PTGS2、AR、MAPK1等25个潜在抗肿瘤靶点,调控FoxO、前列腺癌、癌症、Rap1、TNF、Ras、MAPK信号通路,参与细胞增殖调控、蛋白激酶B信号调控、环氧合酶途径、细胞迁移调控等生物过程,可用于20多种癌症的治疗。结论 本研究为进一步深入研究康莱特注射液抗肿瘤机制提供了新的线索与思路。  相似文献   
34.
《山东中医杂志》2019,(12):1171-1180
目的:基于网络药理学预测射干治疗支气管哮喘的作用机制。方法:通过中药系统药理学技术平台(TCMSP)检索射干化学成分,Swiss Target Prediction数据库得到射干的预测靶点,通过Gene Cards数据库获取哮喘相关靶点将射干的预测靶点与哮喘相关靶点进行映射得到射干治疗哮喘的预测靶点。通过Cytoscape(3.6.0)软件,生成射干治疗哮喘的蛋白与蛋白相互作用(PPI)网络。通过DAVID网站(基因百科全书)进行KEGG通路分析,运用systems Dock网站对预测靶标与其对应的成分进行分子对接。结果:射干活性化合物有17种,筛选出射干可能与哮喘相关的靶点74个,关键靶点共16个,包括雌激素受体α(ESR1)、蛋白激酶C-α(PRKCA)、醛糖还原酶(AR)、蛋白激酶C-delta(PRKCD)、蛋白质激酶C-β(PRKCB)等。通过KEGG通路分析得到128条通路,结合文献检索,筛选出治疗哮喘的可能通路为20条,主要分为以下四类,①气道炎症相关通路:PI3K-Akt信号通路、趋化因子信号通路、MAPK信号通路等;②气道平滑肌相关通路:Ras信号通路、Hippo信号通路、钙信号通路等;③血管增生相关通路:VEGF信号通路;④免疫相关通路:T细胞受体信号通路、Toll样受体信号通路。结论:射干通过多靶点、多通路治疗哮喘,其机制可能与气道炎症相关通路、气道平滑肌相关通路、血管增生相关通路、免疫相关通路的作用相关。  相似文献   
35.
Background: Cellular metabolism generates reactive oxygen species. The oxidation and deamination of the deoxynucleoside triphosphate (dNTP) pool results in the formation of non-canonical, toxic dNTPs that can cause mutations, genome instability, and cell death. House-cleaning or sanitation enzymes that break down and detoxify non-canonical nucleotides play major protective roles in nucleotide metabolism and constitute key drug targets for cancer and various pathogens. We hypothesized that owing to their protective roles in nucleotide metabolism, these house-cleaning enzymes are key drug targets in the malaria parasite.

Methods: Using the rodent malaria parasite Plasmodium berghei we evaluate here, by gene targeting, a group of conserved proteins with a putative function in the detoxification of non-canonical nucleotides as potential antimalarial drug targets: they are inosine triphosphate pyrophosphatase (ITPase), deoxyuridine triphosphate pyrophosphatase (dUTPase) and two NuDiX hydroxylases, the diadenosine tetraphosphate (Ap4A) hydrolase and the nucleoside triphosphate hydrolase (NDH).

Results: While all four proteins are expressed constitutively across the intraerythrocytic developmental cycle, neither ITPase nor NDH are required for parasite viability. dutpase and ap4ah null mutants, on the other hand, are not viable suggesting an essential function for these proteins for the malaria parasite.

Conclusions: Plasmodium dUTPase and Ap4A could be drug targets in the malaria parasite.  相似文献   

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《药学学报(英文版)》2020,10(4):646-666
Drug repurposing is an efficient strategy for new drug discovery. Our latest study found that nitazoxanide (NTZ), an approved anti-parasite drug, was an autophagy activator and could alleviate the symptom of Alzheimer's disease (AD). In order to further improve the efficacy and discover new chemical entities, a series of NTZ-based derivatives were designed, synthesized, and evaluated as autophagy activator against AD. All compounds were screened by the inhibition of phosphorylation of p70S6K, which was the direct substrate of mammalian target of rapamycin (mTOR) and its phosphorylation level could reflect the mTOR-dependent autophagy level. Among these analogs, compound 22 exhibited excellent potency in promoting β-amyloid (Aβ) clearance, inhibiting tau phosphorylation, as well as stimulating autophagy both in vitro and in vivo. What's more, 22 could effectively improve the memory and cognitive impairments in APP/PS1 transgenic AD model mice. These results demonstrated that 22 was a potential candidate for the treatment of AD.  相似文献   
39.
In the last few years the dental implants market has grown both in developed and developing countries, and is associated with high aesthetic expectations and well-being. Although the success rate of commercial implants is high, some problems associated with a lack of initial stability, marginal bony resorption, and periodontal health, remain, especially with immediate placement and loading. The market offers different designs of dental implants, but cylindrical and tapered devices that are fixed to the bone via an external thread are dominant. One lesser-known but potentially useful design is the expandable dental implant (EDI). This paper presents a review of expandable dental implants that encompasses a survey of the literature, published patents, and available commercial devices. We found 15 articles: prospective human trials (n = 4), human case reports (n = 3), published independent discussions of other articles (n = 2), three big animal trials (n = 3), and in silico studies (n = 3). A total of 73 published patents were found and two expandable dental implants are commercially available to date. We propose a classification system that differentiates between the expansion mechanism and the origin of the expanding action. Some expandable designs have been shown to provide good primary stability, but evidence to date is limited. We encourage future clinical and biomechanical studies to clarify and optimise the potential benefits of these implants.  相似文献   
40.
《"健康中国2030"规划纲要》将普及健康知识作为主要目标之一,健康科普已成为公众关注的重要领域,而新媒体已成为公众获取健康知识的主要平台。该研究根据新媒体环境下用户和信息传播的特点,以健康科普视频为实例,制定并研究健康科普视频的创作模式和传播策略,以期对新媒体环境下健康信息普及、公众健康素养提升提供借鉴。  相似文献   
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