Therapeutic regulation of autophagy in hepatic metabolism

Metabolic homeostasis requires dynamic catabolic and anabolic processes. Autophagy, an intracellular lysosomal degradative pathway, can rewire cellular metabolism linking catabolic to anabolic processes and thus sustain homeostasis. This is especially relevant in the liver, a key metabolic organ that governs body energy metabolism. Autophagy's role in hepatic energy regulation has just begun to emerge and autophagy seems to have a much broader impact than what has been appreciated in the field. Though classically known for selective or bulk degradation of cellular components or energy-dense macromolecules, emerging evidence indicates autophagy selectively regulates various signaling proteins to directly impact the expression levels of metabolic enzymes or their upstream regulators. Hence, we review three specific mechanisms by which autophagy can regulate metabolism: A) nutrient regeneration, B) quality control of organelles, and C) signaling protein regulation. The plasticity of the autophagic function is unraveling a new therapeutic approach. Thus, we will also discuss the potential translation of promising preclinical data on autophagy modulation into therapeutic strategies that can be used in the clinic to treat common metabolic disorders.     

Endocannabinoid signaling in microglia

Microglia, the innate immune cells of the central nervous system (CNS), execute their sentinel, housekeeping and defense functions through a panoply of genes, receptors and released cytokines, chemokines and neurotrophic factors. Moreover, microglia functions are closely linked to the constant communication with other cell types, among them neurons. Depending on the signaling pathway and type of stimuli involved, the outcome of microglia operation can be neuroprotective or neurodegenerative. Accordingly, microglia are increasingly becoming considered cellular targets for therapeutic intervention. Among signals controlling microglia activity, the endocannabinoid (EC) system has been shown to exert a neuroprotective role in many neurological diseases. Like neurons, microglia express functional EC receptors and can produce and degrade ECs. Interestingly, boosting EC signaling leads to an anti-inflammatory and neuroprotective microglia phenotype. Nonetheless, little evidence is available on the microglia-mediated therapeutic effects of EC compounds. This review focuses on the EC signals acting on the CNS microglia in physiological and pathological conditions, namely on the CB1R, CB2R and TRPV1-mediated regulation of microglia properties. It also provides new evidence, which strengthens the understanding of mechanisms underlying the control of microglia functions by ECs. Given the broad expression of the EC system in glial and neuronal cells, the resulting picture is the need for in vivo studies in transgenic mouse models to dissect the contribution of EC microglia signaling in the neuroprotective effects of EC-derived compounds.     

miR-132-3p promotes heat stimulation-induced esophageal squamous cell carcinoma tumorigenesis by targeting KCNK2

Epidemiological evidence supports that consumption of high-temperature food and beverages is an important risk factor for esophageal squamous cell carcinoma (ESCC); however, the underlying mechanism still remains unclear. Here, we established a series of animal models and found that drinking 65°C water can promote esophageal tumor progression from preneoplastic lesions to ESCC. RNA sequencing data showed that miR-132-3p was highly expressed in the heat stimulation group compared with controls. Further study verified that miR-132-3p were upregulated in human premalignant lesion tissues of the esophagus, ESCC tissues, and cells. Overexpression of miR-132-3p could promote ESCC cell proliferation and colony formation, whereas knockdown of miR-132-3p could inhibit ESCC progression in vitro and in vivo. Importantly, dual-luciferase reporter assays showed that miR-132-3p could bind with the 3′-untranslated region of KCNK2 and inhibit KCNK2 gene expression. Knockdown or overexpression of KCNK2 could promote or suppress ESCC progression in vitro. These data suggest that heat stimulation can promote ESCC progression and miR-132-3p mediated this process by directly targeting KCNK2.     

PLA2G4和ABCC1基因多态性与支气管哮喘患儿孟鲁司特疗效的研究

目的 探讨胞浆型磷脂酶A2（PLA2G4）基因和ATP结合盒亚家族C成员1（ABCC1）基因单核苷酸多态性（SNPs）与支气管哮喘儿童白三烯受体拮抗剂（LTRA）孟鲁司特疗效的关系。方法 选取2019年3月—2021年9月于中国人民解放军北部战区总医院诊治的121例哮喘患儿为研究对象，受试儿童均采用常规治疗+孟鲁司特方案治疗1个月。应用imLDR^TM技术检测受试儿童PLA2G4基因rs10157410、rs10489409、rs932476位点和ABCC1基因rs215066位点的SNPs，探究各位点不同基因型间治疗前后肺功能、炎症指标及哮喘症状控制水平分级的变化情况。结果 孟鲁司特治疗前后PLA2G4基因rs10157410、rs10489409、rs932476位点不同基因型间的肺功能指标比较，差异均无统计学意义（P >0.05）。孟鲁司特治疗后，PLA2G4基因rs10157410位点GC和GG基因型、rs10489409位点CT和TT基因型、rs932476位点GA和AA基因型及ABCC1基因rs215066位点的第1秒用力呼气容积占预计值百分比、第1秒用力呼气容积与用力肺活量比值、用力呼出50%和75%肺活量时的瞬时流量占预计值百分比均升高（P <0.05）。孟鲁司特治疗后，PLA2G4基因rs10489409位点CC基因型患儿嗜酸性粒细胞计数较治疗前改善不显著（P >0.05），PLA2G4、ABCC1基因各位点不同基因型的免疫球蛋白（IgE）、呼出气一氧化氮均较治疗前改善显著（P <0.05）。孟鲁司特治疗后，PLA2G4基因rs10157410位点GC基因型良好控制比例高于GG基因型，未控制低于GG基因型（P <0.05）；PLA2G4基因rs932476位点GA和AA基因型良好控制比例与GG基因型比较，差异有统计学意义（P <0.05）。Logistic回归分析结果显示，PLA2G4基因rs10157410位点GC基因型良好控制比例是GG基因型的5.639倍［O^R =5.639（95% CI：2.078，15.298）］，rs932476位点GG基因型良好控制比例是AA基因型的0.053倍［O^R =0.053（95% CI：0.006，0.430）］。结论 PLA2G4基因rs10157410位点GC基因型和rs932476位点AA基因型对孟鲁司特具有更好的敏感性。     

Effects of TM6SF2 rs58542926 polymorphism on hepatocellular lipids and insulin resistance in early type 2 diabetes

Background and aimsIncreased hepatocellular lipid content (HCL) is linked to insulin resistance, risk of type 2 diabetes and related complications. Conversely, a single-nucleotide polymorphism (TM6SF2^EK; rs58542926) in the transmembrane 6 superfamily member 2-gene has been associated with nonalcoholic fatty liver disease (NAFLD), but lower cardiovascular risk. This case-control study tested the role of this polymorphism for tissue-specific insulin sensitivity during early course of diabetes.Methods and resultsMales with recent-onset type 2 diabetes with (TM6SF2^EK: n = 16) or without (TM6SF2^EE: n = 16) the heterozygous TM6SF2-polymorphism of similar age and body mass index, underwent Botnia-clamps with [6,6-²H₂]glucose to measure whole-body-, hepatic- and adipose tissue-insulin sensitivity. HCL was assessed with ¹H-magnetic-resonance-spectroscopy. A subset of both groups (n = 24) was re-evaluated after 5 years. Despite doubled HCL, TM6SF2^EK had similar hepatic- and adipose tissue-insulin sensitivity and 27% higher whole-body-insulin sensitivity than TM6SF2^EE. After 5 years, whole-body-insulin sensitivity, HCL were similar between groups, while adipose tissue-insulin sensitivity decreased by 87% and 55% within both groups and circulating triacylglycerol increased in TM6SF2^EE only.ConclusionsThe TM6SF2-polymorphism rs58542926 dissociates HCL from insulin resistance in recent-onset type 2 diabetes, which is attenuated by disease duration. This suggests that diabetes-related metabolic alterations dominate over effects of the TM6SF2-polymorphism during early course of diabetes and NAFLD.     

小鼠CD45-CD31+肺侧群细胞诱导分化的研究

摘要：目的  探讨在体外诱导分化肺侧群细胞（SP）的特性。方法  取小鼠肺组织，流式细胞术分选小鼠白细胞分化抗原（CD）45-/CD31+肺SP；免疫荧光检测分选肺SP三磷酸腺苷结合转运蛋白G超家族成员2（ABCG2）的表达；逆转录聚合酶链反应（RT-PCR）检测肺SP中ABCG2、酪氨酸激酶2（Tie2）及血管性血友病因子（vWF）的表达。细胞体外分化诱导14 d后，免疫荧光检测细胞vWF的表达；RT-PCR检测分化诱导前后细胞中ABCG2和vWF的表达。结果  流式细胞术成功分选出CD45-/CD31+肺SP细胞，免疫荧光检测其表达ABCG2；RT-PCR检测SP表达ABCG2和Tie2，不表达vWF。主群细胞表达vWF；分化诱导前的肺SP表达ABCG2；分化诱导后的肺SP表达vWF。结论  CD45-/CD31+肺SP是血管内皮细胞的祖细胞，具有干细胞分化特性。在体外培养可分化为血管内皮细胞。