Eating ourselves to death (and despair): The contribution of adiposity and inflammation to depression

Obesity and related metabolic conditions are of epidemic proportions in most of the world, affecting both adults and children. The accumulation of lipids in the body in the form of white adipose tissue in the abdomen is now known to activate innate immune mechanisms. Lipid accumulation causes adipocytes to directly secrete the cytokines interleukin (IL) 6 and tumor necrosis factor α (TNFα), but also monocyte chemoattractant protein 1 (MCP-1), which results in the accumulation of leukocytes in fat tissue. This sets up a chronic inflammatory state which is known to mediate the association between obesity and conditions such as cardiovascular disease, type 2 diabetes, and cancer. There is also a substantial literature linking inflammation with risk for depression. This includes the observations that: (1) people with inflammatory diseases such as multiple sclerosis, cardiovascular disease, and psoriasis have elevated rates of depression; (2) many people administered inflammatory cytokines such as interferon α develop depression that is indistinguishable from depression in non-medically ill populations; (3) a significant proportion of depressed persons show upregulation of inflammatory factors such as IL-6, C-reactive protein, and TNFα; (4) inflammatory cytokines can interact with virtually every pathophysiologic domain relevant to depression, including neurotransmitter metabolism, neuroendocrine function, and synaptic plasticity. While many factors may contribute to the association between inflammatory mediators and depression, we hypothesize that increased adiposity may be one causal pathway. Mediational analysis suggests a bi-directional association between adiposity and depression, with inflammation possibly playing an intermediary role.     

高渗盐水对手术伤口愈合的影响及其免疫机理的探讨

本研究比较了高渗盐水和生理盐水处理，对手术小鼠细胞免疫功能和伤口愈合的影响。结果表明，高渗盐水处理组小鼠腹壁切口裂开的张力（１４９．０±９．１ｍｍＨｇ）明显高于生理盐水处理组（１２４．１±９．２ｍｍＨｇ）；高渗盐水处理组的迟发型超敏反应（ＤＴＨ）程度（０．０７３ｇ±０．０２５ｇ）和淋巴细胞增殖能力（刺激指数１８．０±９．６）均明显高于生理盐水处理组（分别为０．０４５ｇ±０．００９ｇ和８．５±７．６）。体外实验还发现，提高培养液中氯化钠的浓度，术后２４ｈ淋巴细胞的活性增加，表明高渗盐水处理具有提高术后小鼠细胞免疫功能及促进伤口愈合的作用     

Molecular characterization of virus-induced autoantibody responses

Here we present a comprehensive molecular mapping of virus-induced autoimmune B cell responses obtained by serological identification of antigens by recombinant expression cloning analysis. Immunoscreening of cDNA expression libraries of various organs (lung, liver, and spleen) using sera from mice infected with cytopathic (vaccinia virus [VV]) or noncytopathic (lymphocytic choriomeningitis virus [LCMV]) viruses revealed a broad specificity of the elicited autoantibody response. Interestingly, the majority of the identified autoantigens have been previously described as autoantigens in humans. We found that induction of virus-induced autoantibodies of the immunoglobulin G class largely depends on the CD40-CD40L-mediated interaction between T and B cells. Furthermore, antibody titers against a number of autoantigens were comparable to the concomitantly induced antiviral antibody response. Comparison of serum reactivity against a selected panel of autoantigens after infection with VV, LCMV, or vesicular stomatitis virus showed that the different virus infections triggered distinct autoantibody responses, suggesting that virus infections may leave specific "autoantibody fingerprints" in the infected host.     

Bifidobacterium adolescentis Isolated from Different Hosts Modifies the Intestinal Microbiota and Displays Differential Metabolic and Immunomodulatory Properties in Mice Fed a High-Fat Diet

The incidence of obesity, which is closely associated with the gut microbiota and chronic inflammation, has rapidly increased in the past 40 years. Therefore, the probiotic-based modification of the intestinal microbiota composition has been developed as a strategy for the treatment of obesity. In this study, we selected four Bifidobacterium adolescentis strains isolated from the feces of newborn and elderly humans to investigate whether supplementation with B. adolescentis of various origins could alleviate obesity in mice. Male C57BL/6J mice fed a high-fat diet (HFD, 60% energy as fat) received one of the following 14-week interventions: (i) B. adolescentis N4_N3, (ii) B. adolescentis Z25, (iii) B. adolescentis 17_3, (iv) B. adolescentis 2016_7_2, and (v) phosphate-buffered saline. The metabolic parameters, thermogenesis, and immunity of all treated mice were measured. Cecal and colonic microbial profiles were determined by 16S rRNA gene sequencing. Intestinal concentrations of short-chain fatty acids (SCFAs) were measured by gas chromatography-mass spectrometry (GC-MS). The B. adolescentis strains isolated from the feces of elderly humans (B. adolescentis Z25, 17_3, and 2016_7_2) decreased the body weight or weight gain of mice, whilst the strain isolated from the newborn (B. adolescentis N4_N3) increased the body weight of mice. The B. adolescentis strains isolated from the elderly also increased serum leptin concentrations and induced the expression of thermogenesis- and lipid metabolism-related genes in brown adipose tissue. All the B. adolescentis strains alleviated inflammations in the spleen and brain and modified the cecal and colonic microbiota. Particularly, all strains reversed the HFD-induced depletion of Bifidobacterium and reduced the development of beta-lactam resistance. In addition, the B. adolescentis strains isolated from the elderly increased the relative abundances of potentially beneficial genera, such as Bacteroides, Parabacteroides, and Faecalibaculum. We speculate that such increased abundance of commensal bacteria may have mediated the alleviation of obesity, as B. adolescentis supplementation decreased the intestinal production of SCFAs, thereby reducing energy delivery to the host mice. Our results revealed that certain strains of B. adolescentis can alleviate obesity and modify the gut microbiota of mice. The tested strains of B. adolescentis showed different effects on lipid metabolism and immunity regulation, with these effects related to whether they had been isolated from the feces of newborn or elderly humans. This indicates that B. adolescentis from different sources may have disparate effects on host health possibly due to the transmission of origin-specific functions to the host.     

Nasal vaccination with CpG oligodeoxynucleotide induces protective immunity against non-typeable Haemophilus influenzae in the nasopharynx

OBJECTIVES: Nasal vaccination is an effective therapeutic regimen for preventing otitis media. Since cholera toxin (CT) is toxic, an alternative adjuvant is required for the development of a nasal vaccine. The efficacy of CpG oligodeoxynucleotide (ODN) as a mucosal adjuvant was examined. METHODS: Mice were immunized intranasally with P6 protein of non-typeable Haemophilus influenzae (NTHi) and adjuvant, CT, or CpG ODN, and P6-specific antibody responses were examined. The expression of P6-specific cytokine mRNA in splenic CD4 T cells was also determined. In addition, NTHi challenges were performed and the NTHi was quantified in nasal washes. RESULTS: P6-specific IgA in nasal wash and serum IgG titers were elevated significantly after nasal immunization. The IgG1/IgG2a ratio in serum from P6+CpG-immunized mice was less than that of P6+CT-immunized mice. Although IL-6 was expression similarly in both groups, IFN-gamma expression was greater in P6+CpG-immunized mice than in P6+CT-immunized mice. Enhanced clearance of NTHi from the nasopharynx was also shown equally in both groups. CONCLUSION: These results indicate that CpG ODN might be an effective mucosal adjuvant, acting by mechanisms that are different from CT. These findings suggest that nasal vaccination with P6 and CpG ODN might be an effective regimen for the induction of NTHi-specific protective immunity.     

针刺对豚鼠血淋巴细胞阿片样肽免疫组织化学反应影响的研究

本文报道对64只豚鼠的血淋巴细胞,分别在电针、给予纳洛酮或外源性阿片样肽(OLP)等不同条件下,以PAP免疫组织化学法显示甲脑啡肽(MEK)、亮脑啡肽(LEK)及β-内啡肽(β-EP)的免疫反应(IR)。另对部分免疫组织化学标本,随后显示酸性非特异性酯酶(ANAE)。约96％的血淋巴细胞呈强弱不等的OLP阳性反应。甲脑啡肽强阳性反应淋巴细胞(MEK-IIRL)和β-EP强阳性反应淋巴细胞,与ANAE的点型淋巴细胞,均呈显著正相关;但LEK强阳性反应淋巴细胞与ANAE的点型淋巴细胞的相关不显著。电针豚鼠“足三里”穴后,MEK、LEK及β-EP的强阳性反应淋巴细胞计数均显著提高。将电针组、纳洛酮组和对照组的结果做比较,见3组间的OLP(包括脑啡肽和内啡肽)的强阳性反应淋巴细胞计数差别皆不显著。但当分别加10~(-7)mol/L MEK、LEK和β-EP体外孵育淋巴细胞后,纳洛酮对OLP强阳性反应淋巴细胞有抑制效应,纳洛酮组和电针组的OLP强阳性反应淋巴细胞计数均呈显著差异。在外加10~(-12)～10~(-3)mol/L MEK体外孵育淋巴细胞后,可见电针组比对照组在10~(-10)～10~(-3)mol/L浓度间MEK免疫反应呈现一个明显高峰,提示电针可能提高潜在未结合的MEK受体的活性。