Psychoneuroimmunology: psychological influences on immune function and health

This review focuses on human psychoneuroimmunology studies published in the past decade. Issues discussed include the routes through which psychological factors influence immune function, how a stressor's duration may influence the changes observed, individual difference variables, the ability of interventions to modulate immune function, and the health consequences of psychosocially mediated immune dysregulation. The importance of negative affect and supportive personal relationships are highlighted. Recent data suggest that immune dysregulation may be one core mechanism for a spectrum of conditions associated with aging, including cardiovascular disease, osteoporosis, arthritis, Type 2 diabetes, certain cancers, and frailty and functional decline; production of proinflammatory cytokines that influence these and other conditions can be stimulated directly by negative emotions and indirectly by prolonged infection.     

Auditory influences on visual temporal rate perception

Visual stimuli are known to influence the perception of auditory stimuli in spatial tasks, giving rise to the ventriloquism effect. These influences can persist in the absence of visual input following a period of exposure to spatially disparate auditory and visual stimuli, a phenomenon termed the ventriloquism aftereffect. It has been speculated that the visual dominance over audition in spatial tasks is due to the superior spatial acuity of vision compared with audition. If that is the case, then the auditory system should dominate visual perception in a manner analogous to the ventriloquism effect and aftereffect if one uses a task in which the auditory system has superior acuity. To test this prediction, the interactions of visual and auditory stimuli were measured in a temporally based task in normal human subjects. The results show that the auditory system has a pronounced influence on visual temporal rate perception. This influence was independent of the spatial location, spectral bandwidth, and intensity of the auditory stimulus. The influence was, however, strongly dependent on the disparity in temporal rate between the two stimulus modalities. Further, aftereffects were observed following approximately 20 min of exposure to temporally disparate auditory and visual stimuli. These results show that the auditory system can strongly influence visual perception and are consistent with the idea that bimodal sensory conflicts are dominated by the sensory system with the greater acuity for the stimulus parameter being discriminated.     

Microbial influences on epithelial integrity and immune function as a basis for inflammatory diseases

Certain autoimmune diseases as well as asthma have increased in recent decades, particularly in developed countries. The hygiene hypothesis has been the prevailing model to account for this increase; however, epidemiology studies also support the contribution of diet and obesity to inflammatory diseases. Diet affects the composition of the gut microbiota, and recent studies have identified various molecules and mechanisms that connect diet, the gut microbiota, and immune responses. Herein, we discuss the effects of microbial metabolites, such as short chain fatty acids, on epithelial integrity as well as immune cell function. We propose that dysbiosis contributes to compromised epithelial integrity and disrupted immune tolerance. In addition, dietary molecules affect the function of immune cells directly, particularly through lipid G-protein coupled receptors such as GPR43.     

Transcultural influences on the perception of parental rearing: a transgenerational study

A random population sample comprised of 790 subjects (380 male and 410 female), aged 15–81 years, completed the EMBU—a reliable and well explored questionnaire directed at assessing experiences of parental rearing. The aim of the study was to investigate to what extent time‐bound cultural changes were reflected in the subjects' experiences of parental rearing. Subjects were divided into four age groups corresponding to various historical and cultural epochs, ranging from those who had experienced World War I and the great depression to those growing up in modern times. The results showed that small but significant changes between the age groups have occurred. In particular, a successive increase in the perception of parents as emotionally warm and caring, and a successive decrease in the experience of parental rejection, was found. The results confirm the importance of the historical cultural context in studies aimed at investigating factors which may contribute to the development of individual vulnerability. Copyright © 1999 John Wiley & Sons, Ltd.     

microRNA对角质形成细胞功能的影响☆

背景：以角质形成细胞为基础的再上皮化过程是皮肤创面得以顺利修复的关键环节之一。有研究报道在小鼠缺血性创面中microRNA-210负向调控角质形成细胞的增殖,阻碍创面再上皮化的进行,提示microRNA可能通过影响角质形成细胞的生物学活动,进而参与创面修复过程。 目的：全面了解microRNA对角质形成细胞生物学活动的影响,指导创面愈合研究领域研究方向的选择,以及为异常创面修复的预防和治疗提供理论依据。 方法：以“keratinocyte,microRNA”为检索词检索PubMed,Embase数据库(2011-05),语言限定为英文。共收集文献59篇,阅读题目和摘要进行初筛,排除研究方向与本文无关、内容重复性研究,共保留12篇文章。对所保留文章的参考文献进行手工检索后,另添加文献30篇以及microRNA数据库2个。 结果与结论：microRNA对角质形成细胞的增殖、分化和移行能力具有调控作用,特别在缺血性创面中对再上皮化有阻碍作用,有望成为一种潜在的治疗靶点。但目前大部分研究仍为体外实验,需要将现有发现向动物模型以及临床研究转化。     

Sex differences and reproductive hormone influences on human odor perception

The question of whether men and women differ in their ability to smell has been the topic of scientific investigation for over a hundred years. Although conflicting findings abound, most studies suggest that, for at least some odorants, women outperform men on tests of odor detection, identification, discrimination, and memory. Most functional imaging and electrophysiological studies similarly imply that, when sex differences are present, they favor women. In this review we examine what is known about sex-related alterations in human smell function, including influences of the menstrual cycle, pregnancy, gonadectomy, and hormone replacement therapy on a range of olfactory measures. We conclude that the relationship between reproductive hormones and human olfactory function is complex and that simple associations between circulating levels of gonadal hormones and measures of olfactory function are rarely present.     

Genetic influences on the immune repertoire following tuberculous infection in mice

Differences in the antibody repertoire between B10 and BALB background strains have been found following intraperitoneal infection of mice with Mycobacterium tuberculosis. Western blot analysis showed that B10 sera reacted with only a few antigenic bands, whereas BALB sera reacted with multiple bands, irrespective of the H-2 (b or k) haplotype. The oligo-banded pattern was a feature of live infection, since immunization with the mycobacterial extract in incomplete Freunds' adjuvant (IFA) produced a multi-banded response in both intact and in previously infected B10 mice. The multibanded BALB phenotype was dominantly expressed in (BALB x B10) F1 hybrids. The extent to which antibody levels to individual antigens varied was influenced by the combined effects of background (non-H-2) and H-2 genes: anti-65,000 molecular weight (MW) and anti-71,000 MW IgG levels were high in BALB but absent or low in B10 mice, irrespective of H-2 haplotypes, anti-19,000 MW levels in B10 mice were strongly H-2 controlled, whilst anti-38,000 MW levels were high in all tested strains. Immunoglobulin G1 (IgG1) subclass antibody and splenic interleukin-4 (IL-4) mRNA levels were distinctly lower in B10 than in BALB mice, but in vitro T-cell proliferative responses to mycobacterial antigens did not differ between the tested strains. It is proposed that the limited extracellular release of mycobacterial antigens required to stimulate B cells and/or differential activation of T-cell subsets may explain the narrow antibody repertoire in B10 strains of mice. This may have relevance to the outcome of infection, as bacterial counts were higher in the BALB strains at 10 weeks post-infection.     

Developmental influences on adult ovarian hormonal function

The hypothesis is advanced that levels of ovarian hormonal function in adult women are associated with the tempo of growth and maturation in childhood and adolescence. Empirical data are presented documenting a correlation between menarcheal age and adult ovarian hormonal function both within and between populations. It is noted that this relationship is compatible with current understanding of the mechanisms underlying pubertal maturation of ovarian hormonal function. Functionally, such a relationship could serve the purpose of modulating adult fecundity to chronic environmental conditions. Alternative hypotheses include the possibility that the relationship is not causal but rather reflects either confounded effects of some common cause or the persistence of acute environmental effects through time. Proper testing of such alternative hypotheses will require longitudinal data on migrant populations, changing environments, or secular trends within populations. The importance of establishing the relationship between development and adult ovarian hormonal function is not limited to issues of fecundity and fertility, but includes other areas of female general and reproductive health. © 1996 Wiley-Liss, Inc.     

Active force perception depends on cerebellar function

Damage to the cerebellum causes characteristic movement abnormalities but is thought to have minimal impact on somatosensory perception. Traditional clinical assessments of patients with cerebellar lesions reveal no perceptual deficits despite the fact that the cerebellum receives substantial somatosensory information. Given that abnormalities have been reported in predicting the visual consequences of movement, we suspect that the cerebellum broadly participates in perception when motor output is required (i.e., active perception). Thus we hypothesize that cerebellar integrity is essential for somatosensory perception that requires motor activity, but not passive somatosensory perception. We compared the perceptual acuity of human cerebellar patients to that of healthy control subjects in several different somatosensory perception tasks with minimal visual information. We found that patients were worse at active force and stiffness discrimination but similar to control subjects with regard to passive cutaneous force detection, passive proprioceptive detection, and passive proprioceptive discrimination. Furthermore, the severity of movement symptoms as assessed by a clinical exam was positively correlated with impairment of active force perception. Notably, within the context of these perceptual tasks, control subjects and cerebellar patients displayed similar movement characteristics, and hence differing movement strategies are unlikely to underlie the differences in perception. Our results are consistent with the hypothesis that the cerebellum is vital to sensory prediction of self-generated movement and suggest a general role for the cerebellum in multiple forms of active perception.     

骆驼奶对慢性乙型肝炎患者免疫应答的影响

目的:研究骆驼奶对慢性乙型肝炎患者免疫应答的影响并探讨其可能的机制.方法:应用酶联免疫吸附试验(ELISA)检测干预喝骆驼奶1年的44例慢性乙型肝炎患者、未采取任何干预措施1年的62例慢性乙型肝炎患者、 20例健康正常对照人3部分人群血清中白细胞介素- 4(IL- 4)、γ干扰素(IFN-γ),同时检测患者血清HBV-DNA、乙肝病毒血清标志物、 ALT及观察其临床疗效.结果:喝骆驼奶组患者血清中Th1类细胞因子IFN-γ的水平(19.33±5.63)高于未喝骆驼奶组(15.10±4.34),P<0.05;Th2类细胞因子IL- 4的水平(29.79±1.20)低于未喝骆驼奶组(48.90±4.30),P <0.01,两者均接近于正常对照组( P >0.05).喝骆驼奶组患者的血清HBV-DNA转阴率90.91%(40/44),未喝骆驼奶组患者的血清HBV-DNA转阴率3.23%(2/62)差异有统计学意义( P <0.01).喝骆驼奶组患者血清HBsAg转阴率 54.55%(24/44),未喝骆驼奶组转阴率1.61%(1/62),差异有统计学意义( P <0.01).喝骆驼奶组患者的ALT均转为正常44(100.00%),未喝骆驼奶组ALT转为正常者7例 (11.29%),差异有统计学意义( P <0.01).结论:骆驼奶通过调节Th1和Th2细胞因子的表达,纠正失衡的Th1/Th2的细胞因子网络,增强细胞免疫及调节免疫功能,抑制病毒DNA复制,促进慢性乙型肝炎患者康复.     

麻醉剂对免疫功能的影响

手术创伤应激和麻醉剂都可引起患者免疫功能的改变,麻醉剂可以直接作用于免疫活性细胞而引起机体细胞和体液免疫的改变.对需长时间使用麻醉剂的术后患者或重症监护病人,合理使用麻醉剂对保持机体免疫功能的稳定具有重要意义.本文就一些常用麻醉剂对免疫活性细胞功能和免疫调节的影响作一综述.     

Intrinsic and environmental influences on immune senescence in the aged monkey.

Several factors associated with the age-related decline in immunity were examined in three studies on aged rhesus monkeys. Natural killer (NK) cell activity was found to be low in many monkeys after 20 years of age, but exceptionally long-lived animals, older than 25 years, often had vigorous cytolytic responses. When NK activity was decreased in an aged monkey, it was predictive of fewer years of survival and a younger age at death. This prediction of mortality was associated with one nonimmune biomarker of aging in the monkey: nail growth rate. Monkeys with very slow nail growth and low NK activity were likely to die sooner. Although these findings might suggest an immutable course for the aging process, the housing conditions of old monkeys also had a pronounced effect on their NK activity. The highest NK responses were found in old monkeys housed with just one other old animal when compared to living alone or with just a young, juvenile monkey. It remains to be determined whether this type of psychosocial influence could have a sustained effect on immunity and ultimately change the pace of aging and time to mortality.     

Ageing of the gut microbiome: Potential influences on immune senescence and inflammageing

Advancing age is accompanied by changes in the gut microbiota characterised by a loss of beneficial commensal microbes that is driven by intrinsic and extrinsic factors such as diet, medications, sedentary behaviour and chronic health conditions. Concurrently, ageing is accompanied by an impaired ability to mount a robust immune response, termed immunesenescence, and age-associated inflammation, termed inflammaging. The microbiome has been proposed to impact the immune system and is a potential determinant of healthy aging. In this review we summarise the knowledge on the impact of ageing on microbial dysbiosis, intestinal permeability, inflammaging, and the immune system and investigate whether dysbiosis of the gut microbiota could be a potential mechanism underlying the decline in immune function, overall health and longevity with advancing age. Furthermore, we examine the potential of altering the gut microbiome composition as a novel intervention strategy to reverse the immune ageing clock and possibly support overall good health during old age.     

Mechanisms by which selenium influences immune responses

Selenium (Se) is an essential dietary trace element that influences immune responses through its incorporation into selenoproteins as the amino acid selenocysteine. This review summarizes data available to date regarding the mechanisms by which Se exerts its effects on inflammation and immune responses. This includes the effects of Se on phagocytes as well as effects on lymphocyte activation, proliferation, and differentiation. Also examined are the known functions of individual selenoproteins for regulating reactive oxygen species and redox potential in leukocytes. Overall, determining how Se contributes to optimal immune responses will depend on a better understanding of the mechanisms by which the selenoproteins, individually and collectively, shape inflammation and immune responses.