Physiological and behavioral contagion/buffering effects of chronic unpredictable stress in a socially enriched environment: A preliminary study

Rodents are sensitive to the emotional state of conspecifics. While the presence of affiliative social partners mitigates the physiological response to stressors (buffering), the partners of stressed individuals show behavioral and endocrine changes indicating that stress parameters can be transmitted across the group members (contagion). In this study, we investigated the social contagion/buffering phenomena in behavior and neuroendocrine mechanisms after exposure to chronic stress, in groups of rats living in the PhenoWorld (PhW). Three groups were tested (8 stressed rats, 8 unstressed rats, and a mixed group with 4 and 4) and these were analyzed under 4 conditions: stressed (pure stress group, n = 8), unstressed (naive control group, n = 8), stressed from mixed group (stressed companion group, n = 8), unstressed from mixed group (unstressed companion group, n = 8. While naive control animals remained undisturbed, pure stress group animals were all exposed to stress. Half of the animals under the mixed-treatment condition were exposed to stress (stressed companion group) and cohabitated with their unstressed partners (unstressed companion group). We confirmed the well-established chronic unpredictable stress (CUS) effects in physiological, behavioral, and neuroendocrine endpoints; body weight gain, open arm entries and time in EPM, and oxytocin receptor expression levels in the amygdala decreased by stress exposure, whereas adrenal weight was increased by stress. Furthermore, we found that playing, rearing and solitary resting behaviors decreased, whereas huddling behavior increased by CUS. In addition, we detected significant increases (stress-buffering) in body weight gain and huddling behaviors between pure stress and stress companion animals, and significant stress contagion effects in emotional behavior and oxytocin receptor expression levels between naive control and control companion groups. Hence, we demonstrate buffering and contagion effects were evident in physiological parameters, emotional behaviors, and social home-cage behaviors of rats and we suggest a possible mediation of these effects by oxytocin neurotransmission. In conclusion, the results herein suggest that the stress status of animals living in the same housing environment influences the behavior of the group.

Home-cage behavior is impacted by stress exposure in rats

Being social animals, rats exhibit a range of social behaviors that help them build social bonds and maintain group cohesion. Behavior is influenced by multiple factors, including stress exposure, and the expression of the impact of stress on both social and non-social behaviors may also be affected by the living conditions of rats. In this study, we explored the physiological and behavioral effects of chronic unpredictable stress on group-housed rats in the PhenoWorld (PhW), a socially and physically enriched environment closer to real-life conditions. Two independent experiments were performed: one in the control condition (PhW control, n = 8) and one in the stress condition (PhW stress, n = 8). Control animals remained undisturbed except for cage cleaning and daily handling procedures. Stress group animals were all exposed to chronic unpredictable stress. Data confirm that stress exposure triggers anxiety-like behavior in the PhW. In terms of home-cage behaviors, we found that stress affects social behaviors (by decreased playing and increased huddling behaviors) and non-social behaviors (as shown by the decrease in rearing and walking behaviors). These results are of relevance to expand our knowledge on the influence of stress on social and non-social behaviors, which are of importance to understand better species-typical behaviors.

The protective effects of hesperidin pretreatment on kidney and remote organs against renal ischemia-reperfusion injury

OBJECTIVE

As an antioxidant and anti-inflammatory agent, Hesperidin was investigated to prove whether it prevents damage to the kidney and lung tissues of rats undergoing renal ischemia-reperfusion injury.

MATERIALS AND METHODS

Four groups of rats were set, including eight subjects each as Group 1 (control), Group 2-RIR (renal ischemia reperfusion), Groups 3 and 4 as pretreatment groups (50 HES, 100 HES).

RESULTS

According to our results, Hesperidin pretreatment improved the biochemical and histopathological parameters in kidney and lung tissues of rats with ischemia-reperfusion injury. Besides, a 100 mg/kg dose of Hesperidin was found to be more beneficial to the rats than 50 mg/kg.

CONCLUSIONS

The study suggests that Hesperidin is protective against renal and lung tissues of rats that underwent ischemia-reperfusion injury.

The relationship between hemoglobin-RDW ratio and clinical outcomes in patients with advanced pancreas cancer

OBJECTIVE

The prognostic significance of hemoglobin (HGB) -red cell distribution width (RDW) ratio (HRR) has been indicated in various cancer types. However, its clinical significance in patients with metastatic pancreas cancer (MPC) is unknown. In this study, we aimed to investigate the prognostic importance of pre-treatment HRR in patients with metastatic pancreas cancer.

PATIENTS AND METHODS

MPC patients (≥18 years of age) who received at least one course of chemotherapy between January 2001 and January 2021, were evaluated retrospectively in terms of pre-treatment HRR values.

RESULTS

Of 111 patients, the mean HRR value was 0.84, and the patients were divided into low HRR and high HRR groups. The median follow-up was 8.7 months (95% CI 1.8-51.6). The median duration of first-line treatment was 4.4 months (95% CI 0.5-31.3). The median overall survival (OS) was 7.6 months (95% CI 3.4-11.8) in the low HRR group and 8.7 months (95% CI 5.7-11.8 months) in the high HRR group (p=0.276) (Figure 1). The median progression-free survival (PFS) was 4.2 months (95% CI 2.7-5.6 months) in the low HRR group and 5.1 months (95% CI 2.8-7.4 months) in the high HRR group (p=0.044) It was found that high HRR decreased progression event in both univariate (HR 0.67, 95% CI 0.45-0.99, p=0.046) and multivariate (HR 0.62, 95% CI 0.42-0.93, p=0.022) analysis.

CONCLUSIONS

The present study emphasized that low HRR was a poor prognostic factor for PFS in patients with MPC. There was no statistically significant difference between the HRR groups regarding OS. This is the first study evaluating the prognostic significance of HRR in MPC.

Factors affecting prognosis and treatment strategies in metastatic soft tissue sarcomas: twenty years of experience

OBJECTIVE

In this study, we aimed to reveal the general clinicopathological features, treatment features, and factors that could predict overall survival in metastatic soft tissue sarcomas, a very rare and heterogeneous disease group.

PATIENTS AND METHODS

This study was a retrospective cohort study. Patients monitored with metastatic soft tissue sarcoma between January 2001 and January 2021 were evaluated retrospectively. Patients aged 18 years and over, histopathologically diagnosed with metastatic STS, and unsuitable for operations, such as local curative surgery or metastasectomy, were included in the study.

RESULTS

A total of 179 patients in the metastatic stage and monitored in our center were included in the study. The median follow-up period was 8.4 months (IQR, 3.4-14.4). 58 (32.4%) patients were de-novo metastatic, and 121 (67.6%) patients developed metastasis later. The median age was 53.2 (Range: 18.8-87.6 years), and 101 (56.4%) patients were male. The most common primary location was the lower extremity (87) (48.6%). The most common histological subtypes were synovial sarcoma (38) (21.2%), pleomorphic sarcoma (37) (20.7%), and liposarcoma (26) (14.5%). The majority were grade 3 tumors (n=131, 73.2%). Having ECOG PS 2-3 (HR=2.829, 95% CI 1,667-4.800, p<0.001), having tumor grade as 3 (HR=1.748, 95% CI 1.150-2.656, p<0.009), receiving palliative chemotherapy (HR=0.294, 95% CI 0.144-0.600, p<0.001), and receiving two or more lines of chemotherapy among those palliative receivers (HR=2.505 95% CI 1.696-3.700, p<0.001) were independent predictive factors of mortality.

CONCLUSIONS

Survival in metastatic soft tissue sarcoma is better in patients with good ECOG performance status, low tumor grades, and who have received palliative chemotherapy. Receiving more than one line of palliative systemic treatment for progressive disease improves survival.

AB0300 LUPUS DISEASE ACTIVITY CORRELATES WITH QUALITY OF LIFE BUT NOT WITH HEALTH LITERACY STATUS

Background:

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease of unknown etiology that can affect any organ of the body. SLE is associated with adverse effects on both health and non-health-related quality of life (HRQOL and non-HRQOL). Lupus PRO is a patient reported outcome measure that has been validated in many languages. It has 44 items that cover both HRQOL and non-HRQOL (1). Health literacy is defined as the degree to which individuals have the capacity to obtain, process and understand basic health information and services needed to make appropriate health decisions. Multiple studies indicate that people with limited health literacy have worse health status and higher rates of hospitalization (2).

Objectives:

We aimed to evaluate the relationship between the LLDAS (Lupus Low Disease Activity State) criteria and the Lupus PRO test, as well as the health literacy status of lupus patients.

Methods:

83 SLE patients (94% women) were included in the study. We performed Lupus PRO and the European Health Literacy Survey tests during the routine follow-up visits of lupus patients to our rheumatology outpatient clinic and admissions to rheumatology inpatient clinic. Available clinical data on medical records were obtained, physician global assessments (PGA) were recorded by the attending physician.

Results:

LLDAS criteria strongly and inversely correlated with the total score, as well as the mood subunit of the Lupus PRO. Similarly, it also significantly inversely correlated with the body appearence and goals subunits. Health literacy status of the patients did not correlate with their LLDAS scores, ie their disease activities.

Conclusion:

Our results suggest that lupus disease activity, assessed by LLDAS criteria, significantly correlates with measures of quality of life, spesicifically Lupus PRO test, but not with health literacy status. Further studies are needed to evaluate if health literacy is related with damage, hospitalization or mortality associated with lupus.

References:

[1]Jolly M, Pickard AS, Block JA, Kumar RB, Mikolaitis RA, Wilke CT, et al., editors. Disease-specific patient reported outcome tools for systemic lupus erythematosus. Seminars in arthritis and rheumatism; 2012: Elsevier.

[2]Paasche-Orlow MK, Parker RM, Gazmararian JA, Nielsen-Bohlman LT, Rudd RR. The prevalence of limited health literacy. Journal of general internal medicine. 2005;20(2):175-84.

Disclosure of Interests:

None declared

The effects of environmental enrichment and transport stress on the weights of lymphoid organs, cell-mediated immune response, heterophil functions and antibody production in laying hens

The effects of environmental enrichment and transport stress on the immune system were investigated in laying hens. A total of 48 1-day-old chickens were used, half of the chickens were reared in conventional cages (RCC) and the rest in enriched cages (REC). Transport stress was applied in the 17th week. Liver weight decreased, spleen and bursa of Fabricius weights, white blood cell count, CD4+ and CD8+ cell proportions increased due to the transport. Environmental enrichment significantly increased antibody production and tended to increase monocyte percentage and CD8+ cell proportion. The effect of transport on, heterophil (H) and lymphocyte (L) percentages was not significant in RCC chickens. While heterophil percentage and H:L ratio increased, lymphocyte percentage decreased in REC chickens subjected to transport. Transport stress increased heterophil functions both in REC and RCC chickens, but the increase was higher in REC hens than in RCC hens. In conclusion, although environmental enrichment did not neutralize the effect of transport on lymphoid organs, it activated the non-specific immune system, cellular and the humoral branches of the specific immune system by increasing heterophil functions, CD8+ cells and antibody production, respectively. Therefore, environmental enrichment suggested for improving animal welfare may also be beneficial to improve the immune system of birds exposed to stress.

Noise stress changes mRNA expressions of corticotropin-releasing hormone, its receptors in amygdala, and anxiety-related behaviors

Noise is a psychological, environmental stressor that activates limbic sites in the brain. Limbic sites such as the amygdala and the amygdaloid corticotropin-releasing hormone (CRH) system play an important role in integrating stress response. We investigated the association between noise exposures, CRH-related molecules in the amygdala, and behavioral alterations. In total 54 Sprague-Dawley rats were divided into the following three groups: Control (CON), acute noise exposure (ANE), and chronic noise exposure (CNE). The ANE group was exposed to 100 dB white noise only once in 4 h and the CNE group was exposed to the same for 4 h per day for 30 days. Expression profiles of CRH and its receptors CRH-R1 and CRH-R2 were analyzed by quantitative real-time polymerase chain reaction (qPCR). The same stress procedure was applied to the ANE and CNE groups for behavior testing. The anxiety responses of the animals after acute and chronic stress exposure were measured in the defensive withdrawal test. CNE upregulated CRH and CRH-R1 mRNA levels but downregulated CRH-R2 mRNA levels. ANE led to a decrease in both CRH-R1 and CRH-R2 expression. In the defensive withdrawal test, while the ANE increased, CNE reduced anxiety-like behaviors. The present study shows that the exposure of rats to white noise (100 dB) leads to behavioral alterations and molecule-specific changes in the CRH system. Behavioral alterations can be related to these molecular changes in the amygdala.

Noise Stress-Induced Changes in mRNA Levels of Corticotropin-Releasing Hormone Family Molecules and Glucocorticoid Receptors in the Rat Brain

Noise is a widespread stress resource that may lead to detrimental effects on the health. However, the molecular basis of the stress response caused by noise remains elusive. We have studied the effects of acute and chronic noise stress on stress-related molecules in the hypothalamus and hippocampus and also corticosterone responses. Sprague Dawley rats were randomized into control, acute and chronic noise stress groups. While the chronic noise stress group animals were exposed to 100 dB white noise for 4 h/a day during 30 days, the acute noise stress group of animals was exposed to the same level of stress once for 4 h. The expression profiles of corticotropin releasing hormone (CRH), CRH1, CRH2 receptors and glucocorticoid receptor (GR) mRNAs were analysed by RT-PCR. Chronic noise stress upregulated CRH mRNA levels in the hypothalamus. Both acute and chronic noise increased CRH-R1 mRNA in the hypothalamus but decreased it in the hippocampus. GR mRNA levels were decreased by chronic noise stress in the hippocampus. The present results suggest that while corticosterone responses have habituated to continuous noise stress, the involvement of CRH family molecules and glucocorticoid receptors in the noise stress responses are different and structure specific.

Long-term aspirin pretreatment in the prevention of cerulein-induced acute pancreatitis in rats

AIM: To investigate the effects of long term pretreatment with low-, medium- and high-dose aspirin (acetylsalicylic acid, ASA) on a model of acute pancreatitis (AP) induced in rats.

METHODS: Forty male Wistar rats were used. Three experimental groups, each consisting of eight animals, received low- (5 mg/kg per day), medium- (150 mg/kg per day) and high-dose (350 mg/kg per day) ASA in supplemented pellet chow for 100 d. Eight animals, serving as the AP-control group, and another eight, serving as reference value (RV) group, were fed with standard pellet chow for the same period. After pretreatment, AP was induced in the experimental animals by intraperitoneal administration of cerulein (2 × 50 μg/kg), while the RV group received saline in the same way. Twelve hours after the second injection, the animals were sacrificed. Pancreatic tissue and plasma samples were collected. One part of the collected pancreatic tissues was used for histopathological evaluation, and the remaining portion was homogenized. Cytokine levels [tumor necrosis factor, interleukin (IL)-1β, IL-6], hemogram parameters, biochemical parameters (amylase and lipase), nuclear factor-κB, aspirin triggered lipoxins and parameters related to the antioxidant system (malondialdehyde, nitric oxide, hemeoxygenase-1, catalase and superoxide dismutase) were measured.

RESULTS: Cerulein administration induced mild pancreatitis, characterized by interstitial edema (total histopathological score of 5.88 ± 0.44 vs 0.25 ± 0.16, P < 0.001). Subsequent pancreatic tissue damage resulted in an increase in amylase (2829.71 ± 772.48 vs 984.57 ± 49.22 U/L, P = 0.001) and lipase (110.14 ± 75.84 U/L vs 4.71 ± 0.78 U/L, P < 0.001) in plasma, and leucocytes (6.89 ± 0.48 vs 4.36 ± 0.23, P = 0.001) in peripheral blood. Cytokines, IL-1β (18.81 ± 2.55 pg/μg vs 6.65 ± 0.24 pg/μg, P = 0.002) and IL-6 (14.62 ± 1.98 pg/μg vs 9.09 ± 1.36 pg/μg, P = 0.04) in pancreatic tissue also increased. Aspirin pretreatment reduced the increase in the aforementioned parameters to a certain degree and partially improved the histopathological alterations caused by cerulein. No evidence of side effects related to chronic ASA administration (e.g., inflammation or bleeding) was observed in the gastrointestinal tract in macroscopic and histopathological examination.

CONCLUSION: Long term ASA pretreatment could prevent and/or ameliorate certain hematological, serological and histological alterations caused by cerulein-induced AP.

Effects of Saccharomyces cerevisiae extract on haematological parameters, immune function and the antioxidant defence system in breeder hens fed aflatoxin contaminated diets

The study was conducted to investigate the efficacy of Saccharomyces cerevisiae extract (SC) on haematological parameters, immune function, and the antioxidant defence system in breeder hens fed a diet contaminated with low level aflatoxin (AF). Forty-eight Ross 308 breeder hens were fed on diets containing AF (0 or 100 µg/kg) and SC (0 or 1 g/kg) in a 2 × 2 factorial arrangement. Red blood cell (RBC), white blood cell (WBC), and platelet counts, differential leucocyte counts, blood CD3+, CD4+, CD8+ and CD5+ T cell ratios, phagocytic activity and oxidative burst of heterophils, plasma and liver catalase activity, and malondialdehyde (MDA) and ascorbic acid concentrations were measured. 3. Plasma and liver MDA concentrations increased (P < 0·05), liver catalase activity decreased (P < 0·05) and total WBC count tended to decrease (P = 0·082) in hens fed the contaminated diet. WBC count, monocyte percentage, phagocytic activity and oxidative burst of heterophils increased (P < 0·05), and plasma MDA concentration tended to decrease (P = 0.088) in SC extract supplemented hens. There was a significant interaction between AF and SC on heterophil, lymphocyte, CD5+ cell percentages, and plasma catalase activity. Blood heterophil percentage decreased but lymphocyte percentage increased in hens fed on the AF contaminated diet without SC supplementation. SC supplementation counteracted the negative effect of AF on heterophils and lymphocytes. The CD5+ cell percentage decreased in unsupplemented hens fed the AF contaminated diet and this negative effect was minimised in SC supplemented hens. Plasma catalase activity increased in SC supplemented hens fed the uncontaminated diet whereas the effect of SC decreased in hens fed the AF contaminated diet. 4. The SC reduced some of the some adverse effects of AF, and improved functions of the non-specific immune system. Therefore, the SC extract which has been used for improving productive performance in birds and mammals may also be useful for modulating some of the effects of a low level, chronic dosage of AF.