大黄[庶虫]虫丸抑制趋化因子配体17表达对CT26小鼠结肠癌的影响

目的观察大黄[庶虫]虫丸对趋化因子配体17(CCL17)在CT26结肠癌小鼠模型中表达的影响,研究其可能的抗肿瘤作用机制。方法复制CT26结肠癌小鼠模型,将模型小鼠随机分为模型组,大黄[庶虫]虫丸高、中、低剂量组(48、24、12 g·kg^-1·d-1),另设正常组。计算各组小鼠结肠癌的抑瘤率;用流式细胞术和免疫荧光法分别检测外周血、肿瘤归巢淋巴结和肿瘤组织细胞中调节性T细胞(Tregs)百分比,肿瘤组织中CCL17的表达,趋化因子受体4(CCR4)在外周血和肿瘤组织细胞表面的表达百分比和肿瘤组织细胞核转录因子κB(NF-κB)p65的表达。结果大黄[庶虫]虫丸能明显抑制小鼠结肠癌的生长,且呈剂量依赖性;大黄[庶虫]虫丸各剂量组肿瘤组织中Tregs明显减少(P<0.05),肿瘤组织中CCL17的荧光强度明显下降(P<0.05);模型组的CCR4+Tregs百分比和CCL17荧光强度最高,大黄[庶虫]虫丸各剂量组随着用药浓度增加,CCR4+Tregs百分比和CCL17荧光强度均表现为依次降低(P<0.05);大黄[庶虫]虫丸能显著抑制结肠癌细胞NF-κB的活化(P<0.05),NF-κB p65的荧光比例显著降低。结论大黄[庶虫]虫丸可通过减少肿瘤组织中Tregs的聚集,降低肿瘤组织中CCL17的表达,下调CCR4在Treg细胞表面的表达比率,降低结肠癌细胞NF-κB p65在细胞内的表达,从而抑制CT26小鼠结肠癌细胞的生长。     

SH2D1A regulates T-dependent humoral autoimmunity

The signaling lymphocytic activation molecule (SLAM)/CD150 family includes a family of chromosome 1-encoded cell surface molecules with costimulatory functions mediated in part by the adaptor protein SH2D1A (SLAM-associated protein, SAP). Deficiency in SH2D1A protects mice from an experimental model of lupus, including the development of hypergammaglobulinemia, autoantibodies including anti-double stranded DNA, and renal disease. This protection did not reflect grossly defective T or B cell function per se because SH2D1A-deficient mice were susceptible to experimental autoimmune encephalomyelitis, a T cell-dependent disease, and they were capable of mounting normal T-independent antigen-specific immunoglobulin responses. Instead, T-dependent antibody responses were impaired in SH2D1A-deficient mice, reflecting defective germinal center formation. These findings demonstrate a specific role for the SLAM-SH2D1A system in the regulation of T-dependent humoral immune responses, implicating members of the CD150-SH2D1A family as targets in the pathogenesis and therapy of antibody-mediated autoimmune and allergic diseases.     

风热清口服液对免疫低下小鼠免疫调节作用的研究

目的:探究风热清口服液对免疫低下小鼠免疫调节的作用。方法:通过给小鼠腹腔注射免疫抑制剂环磷酰胺50 mg/kg,1次/d,连续3 d,建立免疫功能低下的动物模型。应用碳廓清实验、溶血素生成实验和迟发型变态反应,评价风热清口服液对免疫低下小鼠非特异性免疫、体液免疫和细胞免疫的调节作用。结果:风热清口服液低、中剂量组可不同程度提高环磷酰胺致免疫低下小鼠的廓清指数K值(P<0.05)和吞噬指数α值(P<0.05)。风热清口服液低、中、高剂量组可不同程度提高免疫低下小鼠血清溶血素水平(P<0.05)。风热清口服液低、中剂量组可不同程度促进免疫低下小鼠迟发型变态反应(P<0.05)。风热清口服液低剂量组可提高免疫低下小鼠脾脏中CD4+细胞数(P<0.01),并使CD4+/CD8+细胞比值上升(P<0.001),同时抑制免疫低下小鼠脾脏中CD8+细胞数(P<0.05);风热清口服液中、高剂量组可提高免疫低下小鼠脾脏中CD4+/CD8+细胞比值(P<0.01),同时抑制免疫低下小鼠脾脏中CD8+细胞数(P<0.05)。风热清口服液低、中剂量组可显著提高免疫低下小鼠脾指数(P<0.001),风热清口服液低、中、高剂量组均可提高免疫低下小鼠胸腺指数(P<0.05或P<0.01)。结论:风热清口服液通过提高免疫低下小鼠非特异性免疫、体液免疫和细胞免疫,进而增强免疫低下小鼠的免疫功能。     

补肾活血方对慢性特发性血小板减少性紫癜小鼠血小板功能的影响

目的:观察补肾活血方对血小板活化和聚集相关糖蛋白表达的影响,探讨该方是否能够通过改善血小板功能进而治疗慢性特发性血小板减少性紫癜(CITP)。方法:将60只小鼠随机分为正常对照组、CITP模型组、醋酸泼尼松组和补肾活血方组。通过被动免疫造模法成功建立CITP小鼠模型,然后分别用0.9%生理盐水、醋酸泼尼松和补肾活血方干预14 d,采用全自动动物血液分析仪检测小鼠外周血血小板数量和凝血时间;采用流式细胞仪检测各组小鼠血小板活化和聚集相关糖蛋白(CD41、CD61、CD62p、PAC-1)的表达。结果:与正常对照组比较,CITP模型组血小板显著下降、凝血时间显著延长。醋酸泼尼松、补肾活血方干预14 d后,与CITP模型组比较,其血小板显著增加,凝血时间显著下降;其糖蛋白CD41、CD61、CD62p和PAC-1的荧光强度和阳性率显著下降。结论:补肾活血方能在一定程度上有效增加血小板数量和降低凝血时间,并且能够通过改变血小板糖蛋白的表达进而改善血小板的功能,减轻患者的出血。     

APP/PS1小鼠肠道菌群特点及补肾法干预对其的影响

目的:探究不同月龄APP/PS1双转基因模型小鼠的肠道菌群特点及补肾法对其肠道菌群失衡的影响。方法:将8只6个月龄雄性APP/PS1小鼠随机分为模型组和补肾组;4只6个月龄雄性C57BL/6小鼠作为正常对照组。补肾组小鼠给予补肾法中药灌胃3个月,模型组和正常对照组小鼠均予以等体积羧甲基纤维素(CMC)溶液灌胃。留取小鼠灌胃干预前后的粪便,运用16SrDNA技术检测各组肠道菌群的组成结构。从肠道微生态方面,探讨补肾中药对APP/PS1双转基因小鼠肠道菌群构成的影响。结果:6个月龄时模型组和正常对照组小鼠的肠道菌群差异无统计学意义;与9个月龄正常组比较,模型组小鼠肠道内芽孢杆菌纲丰度明显升高。与模型组比较,补肾组肠道内芽孢杆菌纲丰度明显下降,疣微菌门丰度呈上升趋势。结论:APP/PS1小鼠体内均存在肠道菌群失衡的情况,主要与芽孢菌纲、疣微菌门的丰度水平的变化相关。补肾法可以通过降低芽孢菌纲、升高疣微菌门的丰度来进一步改善AD小鼠肠道菌群失衡状态。     

Bilirubin and its oxidation products damage brain white matter

Brain injury after intracerebral hemorrhage (ICH) occurs in cortex and white matter and may be mediated by blood breakdown products, including hemoglobin and heme. Effects of blood breakdown products, bilirubin and bilirubin oxidation products, have not been widely investigated in adult brain. Here, we first determined the effect of bilirubin and its oxidation products on the structure and function of white matter in vitro using brain slices. Subsequently, we determined whether these compounds have an effect on the structure and function of white matter in vivo. In all, 0.5 mmol/L bilirubin treatment significantly damaged both the function and the structure of myelinated axons but not the unmyelinated axons in brain slices. Toxicity of bilirubin in vitro was prevented by dimethyl sulfoxide. Bilirubin oxidation products (BOXes) may be responsible for the toxicity of bilirubin. In in vivo experiments, unmyelinated axons were found more susceptible to damage from bilirubin injection. These results suggest that unmyelinated axons may have a major role in white-matter damage in vivo. Since bilirubin and BOXes appear in a delayed manner after ICH, preventing their toxic effects may be worth investigating therapeutically. Dimethyl sulfoxide or its structurally related derivatives may have a potential therapeutic value at antagonizing axonal damage after hemorrhagic stroke.     

Involvement of Nax sodium channel in peripheral nerve regeneration via lactate signaling

Na_x, a sodium concentration‐sensitive sodium channel, is expressed in non‐myelinating Schwann cells of the adult peripheral nervous system, but the pathophysiological role remains unclear. We found that functional recovery of the hind paw responses from the sciatic nerve transection was delayed in Na_x knockout ( ) mice. Histological analyses showed a decrease in the number of regenerated myelinated axons in sciatic nerves. The delay in the recovery in mice was improved by lactate and inhibited by a monocarboxylate transporter inhibitor. In vitro experiments using cultured Schwann cells showed that lactate release was enhanced by endothelin (ET)‐1 and blocked by an ET receptor type B antagonist. Here, it is conceivable that Na_x was activated by ET‐1. The amount of lactate release by ET‐1 was lower in mice than in wild‐type mice. These results indicated that Na_x is functionally coupled to ET for lactate release via ET receptor type B and is involved in peripheral nerve regeneration.     

Top‐down inputs from the olfactory cortex in the postprandial period promote elimination of granule cells in the olfactory bulb

Elimination of granule cells (GCs) in the olfactory bulb (OB) is not a continual event but is promoted during a short time window in the postprandial period, typically with postprandial sleep. However, the neuronal mechanisms for the enhanced GC elimination during the postprandial period are not understood. Here, we addressed the question of whether top‐down inputs of centrifugal axons from the olfactory cortex (OC) during the postprandial period are involved in the enhanced GC elimination in the OB. Electrical stimulation of centrifugal axons from the OC of anesthetized mice increased GC apoptosis. Furthermore, pharmacological suppression of top‐down inputs from the OC to the OB during the postprandial period of freely behaving mice by γ‐aminobutyric acid (GABA)_A receptor agonist injection in the OC significantly decreased GC apoptosis. Remarkable apoptotic GC elimination in the sensory‐deprived OB was also suppressed by pharmacological blockade of top‐down inputs. These results indicate that top‐down inputs from the OC to the OB during the postprandial period are the crucial signal promoting GC elimination, and suggest that the life and death decision of GCs in the OB is determined by the interplay between bottom‐up sensory inputs from the external world and top‐down inputs from the OC.     

The role of hypothalamic estrogen receptors in metabolic regulation

Estrogens regulate key features of metabolism, including food intake, body weight, energy expenditure, insulin sensitivity, leptin sensitivity, and body fat distribution. There are two ‘classical’ estrogen receptors (ERs): estrogen receptor alpha (ERS1) and estrogen receptor beta (ERS2). Human and murine data indicate ERS1 contributes to metabolic regulation more so than ESR2. For example, there are human inactivating mutations of ERS1 which recapitulate aspects of the metabolic syndrome in both men and women. Much of our understanding of the metabolic roles of ERS1 was initially uncovered in estrogen receptor α-null mice (ERS1^−/−); these mice display aspects of the metabolic syndrome, including increased body weight, increased visceral fat deposition and dysregulated glucose intolerance. Recent data further implicate ERS1 in specific tissues and neuronal populations as being critical for regulating food intake, energy expenditure, body fat distribution and adipose tissue function. This review will focus predominantly on the role of hypothalamic ERs and their critical role in regulating all aspects of energy homeostasis and metabolism.