Stress-induced immunomodulation and the implications for health

Acute rimonabant treatment prevents anhedonia and memory loss in rats submitted to mild restraint stress

Stress-related disorders are becoming increasingly common and are often associated with cognitive impairments. Within this context, the endocannabinoid (ECB) system, particularly the type 1 cannabinoid (CB1) receptor, seems to play a decisive role in restoring body homeostasis. There is consistent evidence in the literature that disrupted CB1-mediated neurotransmission can ultimately contribute to stress-related diseases. Therefore, the present study aimed to evaluate the participation of CB1 receptors in the integrity of stress-induced peripheral and behavioral responses. For this purpose, male adult Wistar rats underwent physical restraint (1 h/day, for 7 days), followed by a single administration of rimonabant (CB1 receptor antagonist, 3 mg/Kg, intraperitonial) at the end of stress protocol. Animals were then subjected to evaluation of neuroendocrine responses, behavioral tests and quantification of Iba-1 (microglial) immunoreactivity in the parvocellular subdivisions of the paraventricular nucleus of the hypothalamus (PVN). No effects of restraint stress or rimonabant administration were detected on body mass variation. However, stress significantly increased adrenal relative mass and corticosterone secretion, and reduced thymus relative size. The stress effects on adrenal size and corticosterone plasma levels were absent in rimonabant-treated rats, but the thymus size was further reduced in the restraint-rimonabant group. Restraint stress also induced anhedonia, a depression-like behavior, and reduced object recognition index, indicating memory recovery impairment. Treatment with the CB1 antagonist significantly reversed stress-induced anhedonia and memory deficit. In the PVN, restraint stress reduced the number of Iba-1 positive cells in the medial parvocellular region of vehicle- but not rimonabant-treated animals. Taken together, these results indicate that the acute inhibition of the CB1-mediated endogenous pathway restores stress-induced depression-like behaviors and memory loss, suggesting a role for endocannabinoids in the neuro-immune-endocrine interplay at both peripheral and hypothalamic levels.

MXene fibers-based molecularly imprinted disposable electrochemical sensor for sensitive and selective detection of hydrocortisone

A molecularly imprinted electrochemical sensor based on MXene fibers was proposed in this work. Firstly, the wet spinning technique prepared MXene fibers with a large aspect ratio, which can make the sheet-like MXene uniformly arranged, avoiding the agglomeration of MXene and improving the electrical conductivity. Afterwards, molecularly imprinted polymers (MIPs) with specific recognition sites were synthesized on the surface of MXene fibers using the electro-polymerization method. The electrochemical sensor utilized the advantages of MXene fibers and molecular imprinting techniques to gain superior selectivity and sensitivity of hydrocortisone (HC). Electrochemical tests with different concentrations of HC (0.5 nM-10.0 μM) under optimal measurement conditions exhibited excellent linearity and a limit of detection (LOD) of 0.17 nM. Furthermore, the electrochemical sensor displayed excellent selectivity, interference resistance, reproducibility, stability and outstanding application performance in serum. This work has promising applications in trace analysis in real sample.

Immediate and Delayed Salivary Cytokine Responses during Repeated Exposures to Cold Pressor Stress

INTRODUCTION

Excessive stress is increasingly recognized as an important trigger of many diseases prevalent in modern societies, and monitoring such stress-related effects could aid prevention. The measurement of salivary markers of inflammation is emerging as a promising tool to non-invasively quantify stress' effects on immune processes in everyday life and thereby detect early aberrations before the manifestation of serious health problems. However, more laboratory-controlled research is needed in order to establish the timescale and determinants of salivary cytokine responses to acute stress.

METHODS

We repeatedly exposed participants to Cold Pressor Stress Test (CPT) or a control procedure and measured a wide array of salivary cytokines as well as subjective, cardiovascular, and cortisol stress reactions. CPT exposure was repeated every 15 min, 3 times in total, with a duration of 3 min each. Saliva was sampled immediately after the first two exposures as well as in 15-min intervals until 60 min after the onset of the first intervention.

RESULTS

We found that many cytokines were detectable in saliva. Specific stress effects were limited to IL-8 and IL-6, however, which decreased immediately or 15 min after stress onset, respectively. Moreover, IL-8 was negatively correlated to cortisol output in the stress but not in the control group. Significant increases were also observed in salivary TNFα and IFNγ; however, these effects were similar under both stress and control conditions.

DISCUSSION

Our results show that particular salivary cytokines may be sensitive to immediate effects of acute CPT-induced stress and also highlight the importance of employing control procedures to discern stress effects from unrelated variations in salivary cytokines.

Evaluation of hydrocortisone as a strain-dependent growth-regulator of Porphyromonasgingivalis

OBJECTIVE

Porphyromonas gingivalis is an oral key pathogen and known to be very diverse in geno- and phenotypes. It is a fastidious bacterium with low O₂-tolerance and 3-7 days of incubation are necessary. With growing interest in the field of microbial endocrinology we explored the potential growth-stimulating effect of hydrocortisone (HC, synonym cortisol) on P. gingivalis cultures.

MATERIAL AND METHODS

Six different P. gingivalis strains were pre-incubated in supplemented Brain-Heart-Infusion broth under appropriate conditions for 24 h, diluted and transferred into microplates. A newly developed and semi-automated spectrophotometric measurement in triplicate, applying a SpectraMax i3x microplate reader at an optical density of 600 nm, was conducted to test growth differences between test group (exposed to a supplement of either 1.25, 2.5, 5, 10, or 20 μg/ml of hydrocortisone) and control group over 48 h of anaerobic incubation (O₂ ≤ 1%). Furthermore, strains were also incubated on HC-supplemented blood agar to test for a possible growth-stimulating effect on solid media.

RESULTS

HC significantly stimulated the lag-phase growth of four out of six P. gingivalis strains. Our data suggest a concentration-dependent growth stimulatory effect of HC between 2.5 and 5 μg/ml, while below 1.25 μg/ml and above 10 μg/ml HC either did not stimulate or inhibited growth.

CONCLUSIONS

HC could reduce the incubation time when isolating P. gingivalis from clinical samples and could boost low biomass cultivations especially during their lag-phase. The growth-modulating effect might be via modulation of virulence factors/quorum sensing gene expression or by reactive oxygen species(ROS)-capturing during early stages of bacterial growth. Further experiments are necessary to explain the mechanism behind our observations.

Effect of phosphodiesterase-4 inhibitor rolipram on colonic hypermotility in water avoidance stress rat model

BACKGROUND

Phosphodiesterase (PDE) inhibition has been reported to play a role in regulating gut motility, but the evidence is insufficient, and the mechanism remains unknown. The aim of this study was to investigate the possible role of phosphodiesterase-4 (PDE4) inhibitor rolipram in water avoidance stress-induced colonic hypermotility.

METHODS

A rat model of irritable bowel syndrome (IBS) with diarrhea (IBS-D) was established by water avoidance stress (WAS). Intestinal motility was assessed by fecal pellets expulsion per hour. The cyclic adenosine monophosphate (cAMP) and nitric oxide (NO) level in colon tissue were detected using ELISA assay and the Griess test, respectively. Western blotting was performed to assess the protein level of PDE, PKA/p-CREB, and neuronal nitric oxide synthase (nNOS) in the colon. To determine the role of rolipram in gut motility, the rats of the WAS + Rolipram and Rolipram group were injected with rolipram intraperitoneally. The colonic contractile activity was recorded with a RM6240 multichannel physiological signal system.

KEY RESULTS

WAS-induced gastrointestinal hypermotility and increased defecation in rats. After repeated stress, protein levels of PDE4 in the colon were promoted while PKA/p-CREB and nNOS were highly decreased. cAMP content in colon tissue did not change significantly. However, NO content decreased after WAS, and rolipram partly enhanced NO in WAS-exposed rats. In addition, intraperitoneal injection of rolipram partly inhibited the colonic motility in vivo. Meanwhile, we observed rolipram inhibited the contraction of colonic smooth muscle strips, and this inhibitory effect was abolished by Nω-Nitro-L-arginine (L-NNA), a nitric oxide synthase (NOS) inhibitor, tetrodotoxin (TTX), a blocker of neuronal voltage-dependent Na⁺ channels, Rp-Adenosine 3',5'-cyclic monophosphorothioate triethylammonium salt hydrate (Rp-cAMPS), an antagonist of cAMP.

CONCLUSIONS AND INFERENCES

Rolipram could relieve stress-induced gastrointestinal hypermotility. This effect may be partly through the cAMP-PKA-p-CREB pathway and NO pathway.

Impact of Acute Blood Loss on Clinical, Hematological, Biochemical, and Oxidative Stress Variables in Sheep

Blood loss in sheep can have different causes and may result in anemia. We aimed to evaluate the clinical, hematological, and biochemical alterations and the oxidative stress generated by acute blood loss. Eighteen healthy sheep underwent phlebotomy to remove 40% of the blood volume and were evaluated clinically and by laboratory tests for clinical, biochemical, and blood gas variables and to assess oxidative stress before induction (T0), 30 min (T30 min), and 6 (T6 h), 12 (T12 h), and 24 h (T24 h) after blood loss. The sheep showed tachycardia from T30 min until T24 h, reduction in the hematocrit, number of erythrocytes, and hemoglobin concentration, with lower values at T24 h and increase in the number of leukocytes from T12 h on. There was a reduction in blood pH and oxygen pressure at T30 min, increased lactate concentration and reduced blood bicarbonate at this time. There was an increase in urea concentration from T6 h until the end of the study, with no change in creatinine levels. The animals did not show changes in the concentration of malonaldehyde, and in the activity of the enzymes superoxide dismutase, glutathione peroxidase, and catalase, but there was a reduction in the concentration of reduced glutathione at T24 h. The acute loss of 40% of blood volume is capable of promoting relevant clinical, hematological, blood gas, and biochemical alterations, and contributed to the appearance of oxidative stress with reduced glutathione concentration, suggesting that this process generated free radicals in sufficient quantity to diminish the action of antioxidants.

Objective and Measurable Biomarkers in Chronic Subjective Tinnitus

Tinnitus is associated with increased social costs and reduced quality of life through sleep disorders or psychological distress. The pathophysiology of chronic subjective tinnitus, which accounts for most tinnitus, has not been clearly elucidated. This is because chronic subjective tinnitus is difficult to evaluate objectively, and there are no objective markers that represent the diagnosis or therapeutic effect of tinnitus. Based on the results of studies on patients with chronic subjective tinnitus, objective and measurable biomarkers that help to identify the pathophysiology of tinnitus have been summarized. A total of 271 studies in PubMed, 303 in EMBASE, and 45 in Cochrane Library were found on biomarkers related to chronic subjective tinnitus published until April 2021. Duplicate articles, articles not written in English, review articles, case reports, and articles that did not match our topic were excluded. A total of 49 studies were included. Three specimens, including blood, saliva, and urine, and a total of 58 biomarkers were used as indicators for diagnosis, evaluation, prognosis, and therapeutic effectiveness of tinnitus. Biomarkers were classified into eight categories comprising metabolic, hemostatic, inflammatory, endocrine, immunological, neurologic, and oxidative parameters. Biomarkers can help in the diagnosis, measure the severity, predict prognosis, and treatment outcome of tinnitus.

Low self-reported stress despite immune-physiological changes in paramedics during rescue operations

Despite the high stress levels, paramedics seem to ignore or even negate the stress. This can be detrimental and lead to stress-related diseases. Therefore, we investigated the divergence between physiological and psychological stress responses of paramedics. Participants were 16 paramedics and 17 white-collar workers. We assessed psychological stress parameters, cortisol awakening response (CAR), and quantified immune parameters. In paramedics, electrocardiogram (ECG) was measured during one complete 24-hour shift. Our results revealed that CAR was higher in paramedics compared to controls. An alteration of immune parameters was observed even during days of free time. Also, ECG recordings showed acute stress in paramedics during rescue situations. Questionnaires revealed that rescue-service specific stressors affect psychological outcomes. However, paramedics reported significantly less mental stress and higher levels of depersonalization than controls. Taken together, our results suggest higher stress in paramedics compared to controls. However, paramedics negate their daily stress. Our findings underline therefore the importance to develop stress-management interventions for paramedics including sensitization for their stress reactions.

Restraint Stress in Hypertensive Rats Activates the Intestinal Macrophages and Reduces Intestinal Barrier Accompanied by Intestinal Flora Dysbiosis

Purpose

Hypertension (HTN) is a major risk factor for cardiovascular disease. In recent years, there were numerous studies on the function of stress in HTN. However, the gut dysbiosis linked to hypertension in animal models under stress is still incompletely understood. Purpose of this study is to use multiple determination method to determine the juvenile stage intestinal bacteria, cytokines and changes in hormone levels.

Methods

Four groups of juvenile male spontaneously hypertensive rats (SHRs) and age-matched male Wistar-Kyoto (WKY) rats were randomly selected as control and experimental groups. Rats in the two stress groups were exposed to restraint stress for 3 hours per day for 7 consecutive days. In one day three times in the method of non-invasive type tail-cuff monitoring blood pressure. The detailed mechanism was illuminated based on the intestinal change using immunohistochemical and immunofluorescence staining and the stress-related hormone and inflammation factors were analyzed via ELISA method. The integrity of the epithelial barrier was assessed using FITC/HRP and the expression levels of proteins associated with the tight junction was detected by Western blot. The alteration of stress-related intestinal flora from ileocecal junction and distal colon were also analyzed using its 16S rDNA sequencing.

Results

The results indicate that acute stress rapidly increases mean arterial pressure which is positive correlation to hormone concentration, especially in SHR-stress group. Meanwhile, stress promoted the enhancement of epithelial permeability accompanied with a reduced expression of the tight junction-related protein and the macrophages (Mφ) aggregation to the lamina propria. There were remarkable significant increase of stress-related hormones and pro-inflammatory factor interleukin (IL)-6 along with a decrease in the diversity of intestinal flora and an imbalance in the F/B ratio.

Conclusion

Our results reveal that stress accompanied with HTN could significantly disrupt the domino effect between intestinal flora and homeostasis.

Linking the hemodynamic consequences of adverse childhood experiences to an altered HPA axis and acute stress response

Adverse childhood experiences (ACEs), such as maltreatment and severe household dysfunction, represent a significant threat to public health as ACEs are associated with increased prevalence of several chronic diseases. Biological embedding, believed to be rooted in dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis, is the prevailing theory by which chronic diseases become imprinted in individuals following childhood adversity. A shift towards HPA axis hypoactivity occurs in response to ACEs exposure and is proposed to contribute towards altered cortisol secretion, chronic low-grade inflammation, and dysregulated hemodynamic and autonomic function. This shift in HPA axis activity may be a long-term effect of glucocorticoid receptor methylation with downstream effects on hemodynamic and autonomic function. Emerging evidence suggests syncopal tendencies are increased among those with ACEs and coincides with altered neuroimmune function. Similarly, chronic low-grade inflammation may contribute towards arterial baroreceptor desensitization through increased arterial stiffness, negatively impacting autonomic regulation following posture change and increasing rates of syncope in later life, as has been previously highlighted in the literature. Although speculative, baroreceptor desensitization may be secondary to increased arterial stiffness and changes in expression of glucocorticoid receptors and arginine vasopressin, which are chronically altered by ACEs. Several research gaps and opportunities exist in this field and represent prospective areas for future investigation. Here, we synthesize current findings in the areas of acute psychosocial stress reactivity pertaining to HPA axis function, inflammation, and hemodynamic function while suggesting ideas for future research emphasizing systemic interactions and postural stress assessments among those with ACEs. This review aims to identify specific pathways which may contribute towards orthostatic intolerance in populations with history of childhood adversity.

Association Between Stressful Life Events and Female Primary Sjogren's Syndrome and Their Role in Disease Activity: A Retrospective Case-Control Study in China

PURPOSE

Previous evidence has shown that psychological stress can trigger the onset of autoimmune disease. This study aimed to investigate the prevalence of stressful life events preceding the onset of symptoms in female primary Sjogren's syndrome (pSS) in China compared to controls and the possible associations of stressful life events with disease activity.

PATIENTS AND METHODS

This was a hospital-based retrospective case-control study. Sixty-seven consecutive female pSS patients and an equal number of age-matched (± 3 years) healthy controls were recruited for assessment using the related Stressful Life Events Scale. The pSS disease activity was measured by the EULAR Sjogren's syndrome disease activity index. Data were analyzed by SPSS, version 23, using chi-square, univariate logistic regression, multiple logistic regression, and partial correlation.

RESULTS

A higher number of negative stressful life events before disease onset in pSS patients compared with healthy controls suggest that these play a role in increasing the risk of disease occurrence (OR = 2.59, 95% CI: 1.87-3.58, p < 0.05). The number of positive life events did not differ between the two groups. Both the number and severity of the negative stressful life events were also significantly correlated with disease activity.

CONCLUSION

Patients with pSS experienced more negative stressful life events in the year preceding the onset of symptoms than controls. Negative stressful life events before symptom onset may be risk factors for pSS and may affect pSS disease activity.

The Effect of Acute Interpersonal Racial Discrimination on Smoking Motivation and Behavior Among Black Smokers: an Experimental Study

In comparison to White smokers, Black smokers are likely to report both more discrimination and less success in smoking cessation. No previous study has tested the causal relationship between an experience of racial discrimination and smoking variables associated with cessation. The goal of this study was to test the causal influence of interpersonal racial discrimination on smoking motivation (i.e., the urge to smoke cigarettes, cessation self-efficacy, and smoking behavior) using a controlled experimental design. We used a virtual ball-playing game to create a laboratory model of racial discrimination. A 2 × 2 between-subjects factorial design (inclusion/exclusion vs. ingroup/outgroup) was used to randomly assign participants to one of four groups: (1) included/ingroup, (2) included/outgroup, (3) excluded/ingroup (ostracism), and (4) excluded/outgroup (racial discrimination). Sixty-nine Black smokers were recruited from the community. Participants in the excluded conditions reported lower cessation self-efficacy than those in the included conditions. Participants in the outgroup conditions had reduced latency to smoke compared to those in the ingroup conditions. There were no main effects of social inclusion on cravings or latency to smoke and no statistically significant interactions for social inclusion × group membership. This laboratory simulation of racial discrimination shows a causal relationship between exclusion and low cessation self-efficacy, which contributes to a better understanding of influences upon smoking cessation attempts among Black smokers.

A multi-omics approach to investigate the inflammatory response to life course socioeconomic position

Aim: Inflammation represents a potential pathway through which socioeconomic position (SEP) is biologically embedded. Materials & methods: We analyzed inflammatory biomarkers in response to life course SEP by integrating multi-omics DNA-methylation, gene expression and protein level in 178 European Prospective Investigation into Cancer and Nutrition-Italy participants. Results & conclusion: We identified 61 potential cis acting CpG loci whose methylation levels were associated with gene expression at a Bonferroni correction. We examined the relationships between life course SEP and these 61 cis-acting regulatory methylation sites individually and jointly using several scores. Less-advantaged SEP participants exhibit, later in life, a lower inflammatory methylome score, suggesting an overall increased expression of the corresponding inflammatory genes or proteins, supporting the hypothesis that SEP impacts adult physiology through inflammation.

Maternal microbiome and the hypertensive disorder of pregnancy, preeclampsia

Preeclampsia (PE) is a pregnancy-specific disorder that can be life threatening for both mother and baby. It is characterized by a new onset hypertension during the second half of pregnancy and affects ~300,000 women in the United States every year. There is no cure for PE, and the only effective treatment is delivery of the placenta and the fetus, which is often preterm. PE is believed to be a severe manifestation of placental dysfunction due to early angiogenic imbalances and inflammatory disturbances; however, the cause of this is unknown. The once thought "sterile" placenta now has been proposed to have a unique microbiome of its own. Under ideal conditions, the microbiome represents a balanced bacterial community that is important to the maintenance of a healthy environment. Dysbiosis of these communities may lead to inflammation that potentially contributes to adverse pregnancy outcomes, such as preterm birth and PE. Thus far, the female reproductive tract microbiome has been found to be influenced by periodontal disease, cardiometabolic complications, and maternal obesity, all of which have been identified as contributors to PE. This review will look at the maternal reproductive tract microbiome, evidence for and against, and its role in pregnancy and PE-related events as well as data from relevant mouse models that could be useful for further investigating the influence of the reproductive tract microbiome on the pathogenesis of PE.

Manifestations of allostatic load in residents of radiation contaminated areas aged 18–24 years

We studied the features of allostatic load (AL) in 100 students aged 18–24 years old who, from birth to adulthood, lived in the territories assigned to the IV radiation zone after the Chornobyl accident (density of soil contamination by isotopes 137Cs 3.7–18.5∙104 Bq/m2) and underwent prolonged exposure to small doses of ionizing radiation. The examined students did not have any clinical signs of the immune-neuroendocrine system dysfunction. 50 people had signs of vegetative-vascular dystonia syndrome (VVD), 48 had signs of moderate hyperthyroidism and 21 had signs of moderate hypothyroidism. During the examination session, as a factor of additional psycho-emotional load, in 66 of the examined the immunoregulatory index CD4+/CD8+ went below the lower limit of the homeostatic norm, in 62 of the examined low density lipoprotein cholesterol (LDL-C) exceeded the upper level. The relative risk (RR) and attributable risk (AR) of the participation of potential secondary factors of allostatic load formation in CD4+/CD8+ immunoregulatory index going below the lower limit were calculated. The presence of statistically significant relative risk of participation in the formation of suppression of the index CD4+/CD8+: the state of hyperthyroidism, state of hypothyroidism, vegetative-vascular dystonia syndrome, higher than normal LDL-C. When the examined students combined the signs of hyperthyroidism, vegetative-vascular dystonia syndrome and higher level of LDL-C; with combination of signs of hypothyroidism, vegetative-vascular dystonia syndrome and higher level of LDL-C. The attributable risk in all cases exceeded 0.10, which confirmed the importance of some of these factors and their complexes in the formation of the effect of reduced immunoregulatory index. The CD4+/CD8+ index can be considered an important biomarker of AL and premature age-related changes in the immune system in residents of radiation-contaminated areas. The risk of AL formation in the case of occurrence of a complex of mediated secondary biomarkers (vegetative-vascular dystonia syndrome, thyroid dysfunction, hypercholesterolemia) is higher compared to their individual significance.

Mind-body medicine use by women diagnosed with breast cancer: results of a nationally representative survey

PURPOSE

Worldwide breast cancer is the most commonly diagnosed cancer in women and often associated with a profound physiological stress reaction. Mind-body medicine modalities have been proven effective in reducing stress symptoms. This article will cover the prevalence of MBM use in women with and without breast cancer in the US population and detect predictors of MBM use in women diagnosed with breast cancer.

METHODS

The 2017 National Health Interview Survey (NHIS) was used to study the prevalence of breast cancer and the use of mind-body medicine (MBM) among individuals with breast cancer in the US population. Using chi-squared tests and backward stepwise multiple logistic regression analyses, predictors of MBM use in women with breast cancer in the past 12 months were identified.

RESULTS

The prevalence of breast cancer in women was 3.1%. Among women diagnosed with breast cancer, 25.2% had used MBM in the past 12 months. Spiritual meditation (14.3%), followed by yoga (9.6%), and mindfulness meditation (4.3%) were the most commonly used MBM approaches for women with breast cancer diagnosis. Only higher education independently predicted the use of MBM among them.

CONCLUSIONS

In this nationally representative sample of the USA, the most common used MBM approach was spiritual meditation, while this approach is much less researched than the evidence based approaches of yoga and mindfulness meditation. Especially stressed individuals worldwide could benefit from MBM the literature suggests. Particularly in the acute survivorship stage, influencing the initial stress reaction could be beneficial.

Psychological Stress and Mitochondria: A Conceptual Framework

BACKGROUND

The integration of biological, psychological, and social factors in medicine has benefited from increasingly precise stress response biomarkers. Mitochondria, a subcellular organelle with its own genome, produce the energy required for life and generate signals that enable stress adaptation. An emerging concept proposes that mitochondria sense, integrate, and transduce psychosocial and behavioral factors into cellular and molecular modifications. Mitochondrial signaling might in turn contribute to the biological embedding of psychological states.

METHODS

A narrative literature review was conducted to evaluate evidence supporting this model implicating mitochondria in the stress response, and its implementation in behavioral and psychosomatic medicine.

RESULTS

Chronically, psychological stress induces metabolic and neuroendocrine mediators that cause structural and functional recalibrations of mitochondria, which constitutes mitochondrial allostatic load. Clinically, primary mitochondrial defects affect the brain, the endocrine system, and the immune systems that play a role in psychosomatic processes, suggesting a shared underlying mechanistic basis. Mitochondrial function and dysfunction also contribute to systemic physiological regulation through the release of mitokines and other metabolites. At the cellular level, mitochondrial signaling influences gene expression and epigenetic modifications, and modulates the rate of cellular aging.

CONCLUSIONS

This evidence suggests that mitochondrial allostatic load represents a potential subcellular mechanism for transducing psychosocial experiences and the resulting emotional responses-both adverse and positive-into clinically meaningful biological and physiological changes. The associated article in this issue of Psychosomatic Medicine presents a systematic review of the effects of psychological stress on mitochondria. Integrating mitochondria into biobehavioral and psychosomatic research opens new possibilities to investigate how psychosocial factors influence human health and well-being across the life-span.

Molecular detection and epidemiological risk factors associated with Cryptosporidium infection among cattle in Peninsular Malaysia

Enteric protozoa infection among cattle may pose a threat to productivity and survival leading to negative impacts on the livestock industry. A number of these pathogens are also known to be zoonotic and are of public health concern. Despite the importance of these enteric protozoa to both animal and human health, there remains a paucity of published information on the epidemiological risk factors that may be associated with bovine cryptosporidiosis in Southeast Asia. The present study was undertaken to determine the molecular prevalence and associated risk factors for Cryptosporidium infection among beef and dairy cattle in Peninsular Malaysia. Faecal samples were collected from 824 cattle in 39 farms (526 beef and 298 dairy) situated in 33 locations throughout the country, and subjected to PCR detection for Cryptosporidium using primers targeting the 18S SSUrRNA gene. Epidemiological variables including host, environment and management factors were subjected to univariate and multivariate logistic regression analyses to determine the potential risk factors for infection. The prevalence of Cryptosporidium among the cattle was 12.5%, with significant difference in the infection rate among the various breeds. There was no significant effect of gender, and both the beef and dairy cattle were at similar odds for infection. The younger cattle had a significantly higher infection rate compared to the older animals. Multivariate analysis revealed that deworming practice, distance to human settlement, geographical location (zone) and farm management system were significant risk factors associated with Cryptosporidium infection. The cattle that were reared on farms located in the northeast of the country, closest (≤200 m) to human settlements, reared extensively, and dewormed every four months were at highest risk of infection. The present study constitutes the first attempt to analyze the multivariable epidemiological risk factors involved in bovine cryptosporidiosis in Malaysia and in Southeast Asia. It is envisaged that the data obtained will facilitate better control and prevention measures for Cryptosporidium infection among cattle in the region. Due to the potential zoonotic nature of the infection, serious steps should be instituted for animal treatment and biohazard waste management on local cattle farms.

Effect of classical conditioning over immature and mature B lymphocytes regulation

Classical conditioning (CC) with a sweet flavored is useful for experimental models of immune response. The objective this work was analyze spleen cell response on the differentiation of B-lymphocytes associated with the CC with sweet flavored in adult rats. Twelve adult male rats were divided (n = 3) in Group 1 (control); Group 2 without conditioned stimulus (WCS) received only water; Group 3 receiving only water with salt; Group 4 (experimental) with CS of sweet flavored and salty flavored afterwards. In every work group, all animals were subjected to the unconditioned stimulus (US) treated by 10 mg/kg body weight of cyclophosphamide injected intraperitoneally (i.p.). Subsequently an immunological challenge with sheep red blood cells i.p. was applied. Spleen samples were obtained 15 days after using euthanasia with 1% sodium thiopental i.p. The evaluation B lymphocyte (immature and mature) was performed by immunohistochemistry using specific antibodies against CD20 and against CD37, and revealed with HRP/DAB. The results show in every work group significant increases of CD20⁺ and CD37⁺ cell densities in the red pulp of the spleen of male adult rats from different groups of the experimental design. We concluded that the immunomodulatory response under CC might facilitate a less aggressive and more physiological immunological response against immunosuppression. RESEARCH HIGHLIGHTS: The immune response can be reinforced by classical conditioning. The sweet taste allows to positively condition the immune response. B lymphocytes actively participate in the immune response and classical conditioning.

Perioperative inhibition of β-adrenergic and COX2 signaling in a clinical trial in breast cancer patients improves tumor Ki-67 expression, serum cytokine levels, and PBMCs transcriptome

Catecholamines and prostaglandins are secreted abundantly during the perioperative period in response to stress and surgery, and were shown by translational studies to promote tumor metastasis. Here, in a phase-II biomarker clinical trial in breast cancer patients (n = 38), we tested the combined perioperative use of the β-blocker, propranolol, and the COX2-inhibitor, etodolac, scheduled for 11 consecutive perioperative days, starting 5 days before surgery. Blood samples were taken before treatment (T1), on the mornings before and after surgery (T2&T3), and after treatment cessation (T4). Drugs were well tolerated. Results based on a-priori hypotheses indicated that already before surgery (T2), serum levels of pro-inflammatory IL-6, CRP, and IFNγ, and anti-inflammatory, cortisol and IL-10, increased. At T2 and/or T3, drug treatment reduced serum levels of the above pro-inflammatory cytokines and of TRAIL, as well as activity of multiple inflammation-related transcription factors (including NFκB, STAT3, ISRE), but not serum levels of cortisol, IL-10, IL-18, IL-8, VEGF and TNFα. In the excised tumor, treatment reduced the expression of the proliferation marker Ki-67, and positively affected its transcription factors SP1 and AhR. Exploratory analyses of transcriptome modulation in PBMCs revealed treatment-induced improvement at T2/T3 in several transcription factors that in primary tumors indicate poor prognosis (CUX1, THRa, EVI1, RORa, PBX1, and T3R), angiogenesis (YY1), EMT (GATA1 and deltaEF1/ZEB1), proliferation (GATA2), and glucocorticoids response (GRE), while increasing the activity of the oncogenes c-MYB and N-MYC. Overall, the drug treatment may benefit breast cancer patients through reducing systemic inflammation and pro-metastatic/pro-growth biomarkers in the excised tumor and PBMCs.

Impact of chronic stress on periodontal health

Introduction: Periodontal diseases are caused by pathogenic microorganisms that induce increases in of local and systemic proinflammatory cytokines, resulting in periodontal damage. The onset and evolution of periodontal diseases are influenced by many local and systemic risk factors. Educational objective: In this article, we aim to review the results of the research on the impact of chronic stress on the occurrence, development, and response to periodontal disease treatments and on the pathophysiological mechanisms of periodontal disease. Conclusion: Chronic stress has a negative impact on the occurrence, development, and response to the treatment of periodontal disease via indirect actions on the periodontium. This can result from behavioral changes caused by stress (poor dental hygiene, smoking, etc.) and a direct neuroimmunoendocrinological action related to the consequences (particularly immunological) of the secretion of certain chemicals (e.g., cortisol) induced by the activation of the hypothalamus and the autonomic nervous system in response to stress. These factors necessitate multidisciplinary management (e.g., physician, oral surgeon, and psychologist) of patients to identify subjects with chronic stress and to employ countermeasures to decrease the impact of stress on the periodontium.

Effects of oregano essential oil on brain TLR4 and TLR2 gene expression and depressive-like behavior in a rat model

The aim of the present study was to evaluate the effects of oregano essential oil (OEO) on the hippocampus and prefrontal cortex TLR 2/4 gene expression and depressive like behavior induced by chronic unpredictable stress (CUS). Sucrose preference and forced swim tests were adopted to examine the antidepressant effect. Control (CON), OEO, CUS, and CUS + OEO groups were used. The OEO and CUS + OEO groups received OEO (0.2 mL/kg, i.p.), CON and CUS received saline (0.2 mL/kg, i.p.), and the positive drug groups of CUS rats received fluoxetine (10 mg/kg) and diazepam (3 mg/kg) once daily for 14 days. The expression of TLR 2/4 was determined using real time quantitative polymerase chain reaction with the SYBR green reporter dye. The compositions of the OEO were determined by gas chromatography-mass spectroscopy. The main constituents were thymol (20.72%), gamma-terpinene (8.83%), borneol (8.72%), cymene (6.83%), carvacrol (6.274%), alfa-terpinene (5.26%), and sabinene (4.92%). Administration of OEO significantly alleviated the depressive symptoms of CUS. A higher level of TLR2/4 mRNA was seen in the brain of CUS group (P < 0.05). The CUS-induced increases in the TLR2/4 levels were not reversed by OEO. According to the present study OEO may have the antidepressant-like activity but have no effect on the stress-induced TLR-2/4 upregulation.

Perceived Stress and Surgical Wound Cytokine Patterns

This was a pilot study to examine pre- and postoperative stress experienced by women who were undergoing autologous breast reconstruction and how stress might impact wound healing, specifically examining cytokines and other chemical mediators in the wound environment. A nonexperimental descriptive design over time was utilized. Participants were women who were undergoing autologous abdominal breast reconstruction for breast cancer (N = 20). Data were collected preoperatively and at 24, 48, 72, and 96 hr postsurgery. Complications were monitored intraoperatively and up to 30 days postsurgery. Psychological stress was measured with the 10-item Perceived Stress Scale (PSS), the Impact of Events Scale-Revised (IES-R), and a 100-mm Visual Analog Scale (VAS). Cytokines were assayed using the 27-plex kit with a Bio-Plex Plus. Although breast cancer is considered a stressor, in this sample of women, scores of the PSS, IES-R, and VAS showed that in fact these participants experienced low levels of psychological stress. All measured biochemical mediators in serum and wound fluid were detected and trends were identified. IL-1ra, IL-6, IL-8, G-CSF, IP-10, MCP-1, MIP-1β, RANTES, and VEGF were present in the highest concentrations. Significant changes in levels of cytokines in wound fluid were observed in IL-1β, IL-2, IL-5, IL-6, IL-8, IL-9, IL-10, IL-17, FGF-basic, G-CSF, MIP-1α, PDGF-bb, MIP-1β, RANTES, and TNF-α. The remaining cytokine concentrations stayed stable over time. These findings suggest that although these women were not experiencing high levels of stress, meaningful cytokine patterns were detected.

A review of metabolic potential of human gut microbiome in human nutrition

The human gut contains a plethora of microbes, providing a platform for metabolic interaction between the host and microbiota. Metabolites produced by the gut microbiota act as a link between gut microbiota and its host. These metabolites act as messengers having the capacity to alter the gut microbiota. Recent advances in the characterization of the gut microbiota and its symbiotic relationship with the host have provided a platform to decode metabolic interactions. The human gut microbiota, a crucial component for dietary metabolism, is shaped by the genetic, epigenetic and dietary factors. The metabolic potential of gut microbiota explains its significance in host health and diseases. The knowledge of interactions between microbiota and host metabolism, as well as modification of microbial ecology, is really beneficial to have effective therapeutic treatments for many diet-related diseases in near future. This review cumulates the information to map the role of human gut microbiota in dietary component metabolism, the role of gut microbes derived metabolites in human health and host-microbe metabolic interactions in health and diseases.

Expression of pro-inflammatory cytokines in the auditory cortex of rats with salicylate-induced tinnitus

Tinnitus often results in severe psychological distress. The present study hypothesized that tinnitus acts as a chronic stressor and induces dysregulation of the production of cytokines. The gap pre‑pulse inhibition of acoustic startle paradigm was applied to test tinnitus‑like behavior in rats. Following this, the mRNA and protein expression levels of interferon (IFN)‑γ, tumor necrosis factor (TNF)‑α, interleukin (IL)‑6 and N‑methyl D‑aspartate receptor subunit 2A (NR2A) were measured in rats subjected to acute and chronic salicylate treatment, using reverse transcription‑quantitative polymerase chain reaction and western blot analysis, respectively. The gap prepulse inhibition of acoustic startle paradigm detected the tinnitus‑like behavior of rats. The expression of TNF‑α and NR2A genes were increased in the auditory cortex (AC) following long‑term administration of salicylate, whereas the expression of IFN‑γ genes decreased; however, the mRNA levels reversed back to normal baseline 14 days following the cease of salicylate administration. IL‑6 gene expression, however, was not fundamentally altered by salicylate treatment. The data demonstrated that chronic salicylate administration induces tinnitus, in part, via dysregulation of cytokines and specific membrane receptors in the AC.

New insights into the effects and mechanism of a classic traditional Chinese medicinal formula on influenza prevention

BACKGROUND

KangBingDu (KBD) is a classic traditional Chinese medicinal formula widely used to treat influenza. However, little information is available from controlled studies regarding the anti-influenza pharmacological activities of KBD and its underlying mechanisms, at least partly due to the lack of appropriate study models.

PURPOSE

We hypothesized that KBD might provide a protection against influenza infection by reducing the host's susceptibility to viruses. To prove it, mouse restraint stress model was employed.

METHODS

Mice were restricted and infected with influenza virus. KBD (13 and 26mg/kg/d) was orally administrated to mice from the first day of restraint stress and lasted for 7 days (twice a day). Mice were monitored daily for morbidity, symptom severity, and mortality for 21 days. The histopathologic changes were examined. For the study of mechanisms of action, we investigated whether KBD could promote mitochondria antiviral signaling protein (MAVS)-mediated antiviral signal and inhibit nuclear factor-kappa B (NF-κB)-mediated inflammation response.

RESULTS

KBD significantly decreased the susceptibility of restraint mice to influenza virus, as evidenced by lowered mortality, attenuated inflammation and reduced viral replications in lungs. Further results revealed that KBD elevated the protein expression of MAVS, which subsequently increased the IFN-β and IFITM3 protein levels, thereby helping to fight viral infections. Finally, we identified that (R,S)-goitrin, mangiferin, forsythin and forsythoside A were effective components in KBD against influenza viral infections.

CONCLUSION

KBD can reduce the susceptibility to influenza virus via mitochondrial antiviral signaling.

Psychological distress in relation to site specific cancer mortality: pooling of unpublished data from 16 prospective cohort studies

OBJECTIVE

 To examine the role of psychological distress (anxiety and depression) as a potential predictor of site specific cancer mortality.

DESIGN

 Pooling of individual participant data from 16 prospective cohort studies initiated 1994-2008.

SETTING

 Nationally representative samples drawn from the health survey for England (13 studies) and the Scottish health survey (three studies).

PARTICIPANTS

 163 363 men and women aged 16 or older at study induction, who were initially free of a cancer diagnosis, provided self reported psychological distress scores (based on the general health questionnaire, GHQ-12) and consented to health record linkage.

MAIN OUTCOME MEASURE

 Vital status records used to ascertain death from 16 site specific malignancies; the three Scottish studies also had information on cancer registration (incidence).

RESULTS

 The studies collectively contributed an average of 9.5 years of mortality surveillance during which there were 16 267 deaths (4353 from cancer). After adjustment for age, sex, education, socioeconomic status, body mass index (BMI), and smoking and alcohol intake, and with reverse causality (by left censoring) and missing data (by imputation) taken into account, relative to people in the least distressed group (GHQ-12 score 0-6), death rates in the most distressed group (score 7-12) were consistently raised for cancer of all sites combined (multivariable adjusted hazard ratio 1.32, 95% confidence interval 1.18 to 1.48) and cancers not related to smoking (1.45, 1.23 to 1.71), as well as carcinoma of the colorectum (1.84, 1.21 to 2.78), prostate (2.42, 1.29 to 4.54), pancreas (2.76, 1.47 to 5.19), oesophagus (2.59, 1.34 to 5.00), and for leukaemia (3.86, 1.42 to 10.5). Stepwise associations across the full range of distress scores were observed for colorectal and prostate cancer.

CONCLUSION

 This study contributes to the growing evidence that psychological distress might have some predictive capacity for selected cancer presentations, in addition to other somatic diseases.

Stress, Anxiety, and Immunomodulation: A Pharmacological Analysis

Stress and stressful events are common occurrences in our daily lives and such aversive situations bring about complex changes in the biological system. Such stress responses influence the brain and behavior, neuroendocrine and immune systems, and these responses orchestrate to increase or decrease the ability of the organism to cope with such stressors. The brain via expression of complex behavioral paradigms controls peripheral responses to stress and a bidirectional link exists in the modulation of stress effects. Anxiety is a common neurobehavioral correlate of a variety of stressors, and both acute and chronic stress exposure could precipitate anxiety disorders. Psychoneuroimmunology involves interactions between the brain and the immune system, and it is now being increasingly recognized that the immune system could contribute to the neurobehavioral responses to stress. Studies have shown that the brain and its complex neurotransmitter networks could influence immune function, and there could be a possible link between anxiogenesis and immunomodulation during stress. Physiological and pharmacological data have highlighted this concept, and the present review gives an overview of the relationship between stress, anxiety, and immune responsiveness.

A life course approach to explore the biological embedding of socioeconomic position and social mobility through circulating inflammatory markers

Lower socioeconomic position (SEP) has consistently been associated with poorer health. To explore potential biological embedding and the consequences of SEP experiences from early life to adulthood, we investigate how SEP indicators at different points across the life course may be related to a combination of 28 inflammation markers. Using blood-derived inflammation profiles measured by a multiplex array in 268 participants from the Italian component of the European Prospective Investigation into Cancer and Nutrition cohort, we evaluate the association between early life, young adulthood and later adulthood SEP with each inflammatory markers separately, or by combining them into an inflammatory score. We identified an increased inflammatory burden in participants whose father had a manual occupation, through increased plasma levels of CSF3 (G-CSF; β = 0.29; P = 0.002), and an increased inflammatory score (β = 1.96; P = 0.029). Social mobility was subsequently modelled by the interaction between father's occupation and the highest household occupation, revealing a significant difference between "stable Non-manual" profiles over the life course versus "Manual to Non-manual" profiles (β = 2.38, P = 0.023). Low SEP in childhood is associated with modest increase in adult inflammatory burden; however, the analysis of social mobility suggests a stronger effect of an upward social mobility over the life course.

Maternal Microbiome and Pregnancy Outcomes That Impact Infant Health: A Review

The maternal microbiome is recognized as a key determinant of a range of important maternal and child health outcomes, and together with perinatal factors influences the infant microbiome. This article provides a summary review of research investigating (1) the role of the maternal microbiome in pregnancy outcomes known to adversely influence neonatal and infant health, including preterm birth, cardiometabolic complications of pregnancy such as preeclampsia and gestational diabetes, and excessive gestational weight gain; (2) factors with an established link to adverse pregnancy outcomes that are known to influence the composition of the maternal microbiome; and (3) strategies for promoting a healthy maternal microbiome, recognizing that much more research is needed in this area.

Bidirectional psychoneuroimmune interactions in the early postpartum period influence risk of postpartum depression

More than 500,000 U.S. women develop postpartum depression (PPD) annually. Although psychosocial risks are known, the underlying biology remains unclear. Dysregulation of the immune inflammatory response and the hypothalamic-pituitary-adrenal (HPA) axis are associated with depression in other populations. While significant research on the contribution of these systems to the development of PPD has been conducted, results have been inconclusive. This is partly because few studies have focused on whether disruption in the bidirectional and dynamic interaction between the inflammatory response and the HPA axis together influence PPD. In this study, we tested the hypothesis that disruption in the inflammatory-HPA axis bidirectional relationship would increase the risk of PPD. Plasma pro- and anti-inflammatory cytokines were measured in women during the 3rd trimester of pregnancy and on Days 7 and 14, and Months 1, 2, 3, and 6 after childbirth. Saliva was collected 5 times the day preceding blood draws for determination of cortisol area under the curve (AUC) and depressive symptoms were measured using the Edinburgh Postpartum Depression Survey (EPDS). Of the 152 women who completed the EPDS, 18% were depressed according to EDPS criteria within the 6months postpartum. Cortisol AUC was higher in symptomatic women on Day 14 (p=.017). To consider the combined effects of cytokines and cortisol on predicting symptoms of PPD, a multiple logistic regression model was developed that included predictors identified in bivariate analyses to have an effect on depressive symptoms. Results indicated that family history of depression, day 14 cortisol AUC, and the day 14 IL8/IL10 ratio were significant predictors of PPD symptoms. One unit increase each in the IL8/IL10 ratio and cortisol AUC resulted in 1.50 (p=0.06) and 2.16 (p=0.02) fold increases respectively in the development of PPD. Overall, this model correctly classified 84.2% of individuals in their respective groups. Findings suggest that variability in the complex interaction between the inflammatory response and the HPA axis influence the risk of PPD.

High responders and low responders: factors associated with individual variation in response to standardized training

The response to an exercise intervention is often described in general terms, with the assumption that the group average represents a typical response for most individuals. In reality, however, it is more common for individuals to show a wide range of responses to an intervention rather than a similar response. This phenomenon of 'high responders' and 'low responders' following a standardized training intervention may provide helpful insights into mechanisms of training adaptation and methods of training prescription. Therefore, the aim of this review was to discuss factors associated with inter-individual variation in response to standardized, endurance-type training. It is well-known that genetic influences make an important contribution to individual variation in certain training responses. The association between genotype and training response has often been supported using heritability estimates; however, recent studies have been able to link variation in some training responses to specific single nucleotide polymorphisms. It would appear that hereditary influences are often expressed through hereditary influences on the pre-training phenotype, with some parameters showing a hereditary influence in the pre-training phenotype but not in the subsequent training response. In most cases, the pre-training phenotype appears to predict only a small amount of variation in the subsequent training response of that phenotype. However, the relationship between pre-training autonomic activity and subsequent maximal oxygen uptake response appears to show relatively stronger predictive potential. Individual variation in response to standardized training that cannot be explained by genetic influences may be related to the characteristics of the training program or lifestyle factors. Although standardized programs usually involve training prescribed by relative intensity and duration, some methods of relative exercise intensity prescription may be more successful in creating an equivalent homeostatic stress between individuals than other methods. Individual variation in the homeostatic stress associated with each training session would result in individuals experiencing a different exercise 'stimulus' and contribute to individual variation in the adaptive responses incurred over the course of the training program. Furthermore, recovery between the sessions of a standardized training program may vary amongst individuals due to factors such as training status, sleep, psychological stress, and habitual physical activity. If there is an imbalance between overall stress and recovery, some individuals may develop fatigue and even maladaptation, contributing to variation in pre-post training responses. There is some evidence that training response can be modulated by the timing and composition of dietary intake, and hence nutritional factors could also potentially contribute to individual variation in training responses. Finally, a certain amount of individual variation in responses may also be attributed to measurement error, a factor that should be accounted for wherever possible in future studies. In conclusion, there are several factors that could contribute to individual variation in response to standardized training. However, more studies are required to help clarify and quantify the role of these factors. Future studies addressing such topics may aid in the early prediction of high or low training responses and provide further insight into the mechanisms of training adaptation.

Does stress predispose to periodontal disease?

The relationship of a sound mind to the maintenance of a healthy body has been recognized throughout most of recorded history. The term 'stress' is used to describe adverse emotions or reactions to unpleasant experiences. Individuals with high levels of stress and poor coping skills experience twice as much periodontal disease as compared to those with minimal stress and good coping skills. Although stress may predispose an individual to more destruction from periodontitis, the presence of periodontal pathogens remains the essential aetiologic factor. This review presents a summary of stress, discussing how it can predispose an individual to periodontal disease.

CLINICAL RELEVANCE

Stress, which is a universal phenomenon, is implicated to have various systemic effects besides being a risk factor for periodontal disease. This article elucidates the relationship between psycho-social stress and destructive periodontal disease.

Immune dysregulation and glucocorticoid resistance in minority and low income pregnant women

Chronic prenatal stress contributes to poor birth outcomes for women and infants. Importantly, poor birth outcomes are most common among minority and low income women. To investigate underlying mechanisms, we tested the hypothesis that chronic stress related to minority or low income status is associated with glucocorticoid resistance as indicated by disruption in the cytokine-glucocorticoid feedback circuit. Home visits were conducted during which 3rd trimester pregnant women completed stress and depression surveys and provided blood for pro- and anti-inflammatory cytokines. Saliva was collected 5 times the preceding day for diurnal cortisol levels. For statistical analyses, women were grouped 3 ways, by race, income, and the presence or absence of either of those risk factors; this last group was labeled high or low general risk. Immune regulation was evaluated by evidence of a functioning negative feedback relationship between cytokines and cortisol. Of 96 participants, 18 were minority, 22 of low income, and 29 either minority or low income (high general risk). Pearson partial correlation identified a significant negative relationship between cortisol area under the curve (AUC) and pro- to anti-inflammatory cytokine ratios in the low general risk women (i.e., Caucasian, higher income) including IFNγ/IL10 (r=-0.73, p<0.0001), IL6/IL10 (r=-0.38, p=0.01), IL1β/IL10 (r=-0.44, p=0.004) and TNFα/IL10 (r=-0.41; p=0.005); no such correlations existed in the high general risk women (i.e., minority, low income) for (IFNγ/IL10: r=-0.25, p=0.43; IL6/IL10: r=0.12, p=0.70; IL1 β/IL10: r=0.05, p=0.87; TNFα/IL10: r=0.10; p=0.75), suggestive of glucocorticoid resistance. Cortisol levels throughout the day also were higher in minority and high general risk groups (p<0.05). Without cytokine glucocorticoid feedback, a pregnant woman's ability to regulate inflammation is limited, potentially contributing to adverse maternal and infant outcomes.

The effect of stress on periodontitis: A clinicobiochemical study

BACKGROUND

Clinical and epidemiological data suggest that negative life experience events, like depression, may contribute to an increased susceptibility to periodontal disease.

AIM

To study the association between psychological stress and chronic periodontitis.

MATERIALS AND METHODS

One hundred and eleven dentate individuals, of age 40 years and above, were selected. The clinical examination included, the number of teeth present, plaque index, Probing Pocket Depth, and Clinical Attachment Level. Assessment of Psychological stress levels were done by a questionnaire and were correlated with salivary cortisol levels, which were estimated biochemically by using the Enzyme-Linked Immunosorbent Assay (ELISA) method.

RESULTS

Statistical analysis was done by using the student 't' test and Mann Whitney test. According to our observation, chronic periodontitis showed a significant correlation with hypercortisolemia (P<0.0001), work tension (P=0.04), economic problems (P<0.0001), clinical stress syndrome (P<0.0001), plaque index (P<0.0001), and unsecured job (P=0.003).

CONCLUSION

Stress may be considered as an important risk factor for periodontal disease. Routine salivary cortisol assessment may be an economical and useful diagnostic marker to rule out stress in periodontitis patients.

The stressful life events and Parkinson's disease: a case-control study

A case-control study was conducted in order to investigate the possible link between stressful life events and Parkinson's disease (PD). A group of 110 consecutive newly diagnosed PD cases treated at the Institute of Neurology, Faculty of Medicine, Belgrade University, was compared with a control group comprising 220 subjects with degenerative joint disease and some diseases of the digestive tract. The case and control subjects were matched by sex, age (±2 years) and place of residence (urban/rural). According to conditional multivariate logistic regression analysis, PD was found to be significantly related to retirement (odds ratio--OR 18.73, 95% confidence interval--95%CI 1.9-175.4), birth of own child (OR 66.22, 95%CI 8.3-526.3) and air raids (OR 5.66, 95%CI 2.4-13.5). The risk of PD significantly increased with the number of stressful events. The results of the present study support the hypothesis that stress may play a role in the development of PD.

Anti-stress effects of carnosine on restraint-evoked immunocompromise in mice through spleen lymphocyte number maintenance

Carnosine (β-alanyl-L-histidine), a naturally occurring dipeptide, has been characterized as a putative neurotransmitter and serves as a reservoir for brain histamine, which could act on histaminergic neurons system to relieve stress-induced damages. However, understanding of the role of carnosine in stress-evoked immunocompromise is limited. In this study, results showed that when mice were subjected to restraint stress, spleen index and the number of spleen lymphocytes including Natural Killer (NK) cells were obviously decreased. Results also demonstrated that restraint stress decreased the cytotoxic activity of NK cells per spleen (LU₁₀/spleen) while the activity of a single NK cell (LU₁₀/10⁶ cells) was not changed. However, oral administration of carnosine (150 and 300 mg/kg) increased spleen index and number of spleen lymphocytes (including NK cells), and elevated the cytotoxic activity of NK cells per spleen in restraint-stressed mice. These results indicated that carnosine ameliorated stress-evoked immunocompromise through spleen lymphocyte number maintenance. Carnosine was further found to reduce stress-induced elevation of plasma corticosterone level. On the other hand, results showed that carnosine and RU486 (a glucocorticoids receptor antagonist) treatment prevented the reduction in mitochondrion membrane potential and the release of mitochondrial cytochrome c into cytoplasm, increased Bcl-2/Bax mRNA ratio, as well as decreased terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL)-positive cells in spleen lymphocytes of stressed mice. The results above suggested that the maintenance of spleen lymphocyte number by carnosine was related with the inhibition of lymphocytes apoptosis caused by glucocorticoids overflow. The stimulation of lymphocyte proliferation by carnosine also contributed to the maintenance of spleen lymphocyte number in stressed mice. In view of the elevated histamine level, the anti-stress effects of carnosine on restraint-evoked immunocompromise might be via carnosine-histamine metabolic pathway. Taken together, carnosine maintained spleen lymphocyte number by inhibiting lymphocyte apoptosis and stimulating lymphocyte proliferation, thus prevented immunocompromise in restraint-stressed mice.

Opioid drug abuse and modulation of immune function: consequences in the susceptibility to opportunistic infections

Infection rate among intravenous drug users (IDU) is higher than the general public, and is the major cause of morbidity and hospitalization in the IDU population. Epidemiologic studies provide data on increased prevalence of opportunistic bacterial infections such as TB and pneumonia, and viral infections such as HIV-1 and hepatitis in the IDU population. An important component in the intravenous drug abuse population and in patients receiving medically indicated chronic opioid treatment is opioid withdrawal. Data on bacterial virulence in the context of opioid withdrawal suggest that mice undergoing withdrawal had shortened survival and increased bacterial load in response to Salmonella infection. As the body of evidence in support of opioid dependency and its immunosuppressive effects is growing, it is imperative to understand the mechanisms by which opioids exert these effects and identify the populations at risk that would benefit the most from the interventions to counteract opioid immunosuppressive effects. Thus, it is important to refine the existing animal model to closely match human conditions and to cross-validate these findings through carefully controlled human studies. Better understanding of the mechanisms will facilitate the search for new therapeutic modalities to counteract adverse effects including increased infection rates. This review will summarize the effects of morphine on innate and adaptive immunity, identify the role of the mu opioid receptor in these functions and the signal transduction activated in the process. The role of opioid withdrawal in immunosuppression and the clinical relevance of these findings will also be discussed.

Carnosine ameliorates stress-induced glucose metabolism disorder in restrained mice

Carnosine is a natural dipeptide that has shown multiple benefits in the treatment of various diseases. This study investigated the ameliorative effects of carnosine on glucose metabolism in restraint-stressed mice. Our results showed that restraint stress could significantly influence glucose metabolism, as reflected by lowered glucose tolerance, hepatic and muscle glycogen content, and increased plasma corticosterone concentration in mice. Oral administration of carnosine (150 and 300 mg/kg) not only reverted stress-induced decline in glucose tolerance and glycogen content in liver and muscle, but also reduced plasma corticosterone level. Carnosine has also significantly suppressed mRNA expression of glucose-6-phosphatase, while elevating glycogen synthase 2, glucokinase and glucose transporter 2 expressions in the liver. The obtained results demonstrated the harmful effects induced by restraint stress, while proving that carnosine could ameliorate stress-induced glucose metabolism disturbance. It is presumable that carnosine exerts its anti-stress effects by indirectly affecting the histaminergic neuron system, modulating the stress-activated hypothalamic-pituitary-adrenal axis and improving glucose metabolism through regulation of the enzymes in the glucose metabolic pathways.

The complex interplay between stress and bacterial infections in animals

Over the past decade, an increasing awareness has arisen of the role of neuroendocrine hormones in the susceptibility of mammalian hosts to a bacterial infection. During a stress response, glucocorticoids, catecholamines and neuroendocrine factors are released into the circulation of the host. For a long time the effects of stress on the course of an infection have been exclusively ascribed to the direct effect of stress-related hormones on the immune system and the intestinal barrier function. Chronic stress is known to cause a shift from T helper 1-mediated cellular immunity toward T helper 2-mediated humoral immunity, which can influence the course of an infection and/or the susceptibility to a microorganism. Bacteria can however also respond directly to stress-related host signals. Catecholamines can alter growth, motility, biofilm formation and/or virulence of pathogens and commensal bacteria, and as a consequence influence the outcome of infections by these bacteria in many hosts. For some bacteria, such as Salmonella, Escherichia coli and Pseudomonas aeruginosa it was shown that this influence is regulated by quorum sensing mechanisms. In this manuscript an overview of how and when stress influences the outcome of bacterial infections in animals is provided.

Effects of consumption of a fermented dairy product containing the probiotic Lactobacillus casei DN-114 001 on common respiratory and gastrointestinal infections in shift workers in a randomized controlled trial

OBJECTIVE

The risk of infection may be increased in people under stress such as shift workers. This study examined the effect of a fermented dairy product containing the probiotic Lactobacillus casei DN-114 001 (verum) on the incidence of respiratory and gastrointestinal common infectious diseases (CIDs) and on immune functions in healthy shift workers.

METHODS

The study was single-center, randomized, double-blind, and controlled. Volunteers received 200 g/day of verum (n = 500) or control product (n = 500) for 3 months; 1-month follow-up was carried out.

RESULTS

The cumulated number of CIDs (primary outcome) was not significantly different between groups. Because the Poisson distribution of the primary parameter did not fully fit the observed data, a post hoc categorical analysis was applied and showed a significantly lower cumulated number of CIDs in the verum group during the product consumption phase (odds ratio [OR] = 0.75, 95% confidence interval [CI] 0.59-0.95, p = 0.017). Verum also reduced the proportion of volunteers experiencing at least 1 CID (43% vs. 51%, p = 0.005), increased the time to the first occurrence of CID (p = 0.017) in the whole population, and reduced the cumulated number of CIDs in the subgroup of smokers (p = 0.033). In the course of CID, cumulated duration of fever was lower in the verum group (in the whole study phase) (p = 0.022), and an increase in leukocyte, neutrophil, and natural killer (NK) cell counts and activity (p = 0.047 to p < 0.001) was observed compared with control group. Verum was safe and well tolerated.

CONCLUSION

The results indicate that daily consumption of a fermented dairy product containing Lactobacillus casei DN-114 001 could reduce the risk of common infections in stressed individuals such as shift workers.

Morphine withdrawal stress modulates lipopolysaccharide-induced interleukin 12 p40 (IL-12p40) expression by activating extracellular signal-regulated kinase 1/2, which is further potentiated by glucocorticoids

Withdrawal stress is a common occurrence in opioid users, yet very few studies have examined the effects of morphine withdrawal (MW) on immune functioning or the role of glucocorticoids in MW-induced immunomodulation. This study investigated for the first time the role of glucocorticoids in MW modulation of LPS-induced IL-12p40, a key cytokine playing a pivotal role in immunoprotection. Using WT and μ-opioid receptor knock-out mice, we show that MW in vivo significantly attenuated LPS-induced IL-12p40 mRNA and protein expression. The role of glucocorticoids in MW modulation of IL-12p40 was investigated using a murine macrophage cell line, CRL2019, in an in vitro MW model. Interestingly, MW alone in the absence of glucocorticoids resulted in a significant reduction in IL-12p40 promoter activity and mRNA and protein expression. EMSA revealed a concurrent decrease in consensus binding to transcription factors NFκB, Activator Protein-1, and CCAAT/enhancer-binding protein and Western blot analysis demonstrated a significant activation of LPS-induced ERK1/2 phosphorylation. Interestingly, although glucocorticoid treatment alone also modulated these transcription factors and ERK1/2 activation, the addition of glucocorticoids to MW samples resulted in a greater than additive reduction in the transcription factors and significant hyperactivation of LPS-induced ERK1/2 phosphorylation. ERK inhibitors reversed MW and MW plus corticosterone inhibition of LPS-induced IL-12p40. The potentiating effects of glucocorticoids were non-genomic because nuclear translocation of glucocorticoid receptor was not significantly different between MW and corticosterone treatment. This study demonstrates for the first time that MW and glucocorticoids independently modulate IL-12p40 production through a mechanism involving ERK1/2 hyperactivation and that glucocorticoids can significantly augment MW-induced inhibition of IL-12p40.

Pandemic (H1N1) 2009 virus revisited: an evolutionary retrospective

The pandemic (H1N1) 2009 virus is unique in many aspects, especially in its genetics and evolution. In this paper, we examine the molecular mechanisms underlying the evolution of this novel virus through a comprehensive bioinformatics analysis, and present results in the context of a review of the literature. The pandemic virus was found to arise from a reassortment of two swine viruses, each of which ultimately arose from interspecies transmission. It experienced fast evolutionary rates and strong selection pressures, diverging into two different clusters at the early pandemic stage. Cluster I became extinct at the end of 2009 whereas Cluster II continued to circulate at much lower rates in 2010. Therefore, on August 10 of 2010 the WHO declared the end of the pandemic. Important mutations associated with host specificity, virulence, and drug resistance were detected in the pandemic virus, indicating effective transmission and increased severity in humans. Much has been learned about the evolutionary dynamics of this pandemic virus; however, it is still impossible to predict when the next pandemic will occur and which virus will be responsible. Improved surveillance at different levels (both national and international) and in different hosts (especially in swine) appears to be crucial for early detection and prevention of future influenza pandemics.