Shift Work Predicts Increases in Lipopolysaccharide-Binding Protein, Interleukin-10, and Leukocyte Counts in a Cross-Sectional Study of Healthy Volunteers Carrying Low-Grade Systemic Inflammation

The disruption of inflammatory responses is a potential mechanism behind the harmful effects of shift work and is associated with increased risk of hypertension, stroke, obesity, diabetes, and cancer. These responses are linked to the proliferation of leukocytes in shift workers, suggesting a systemic signal as a potential mediator. The purpose of this study was to assess the relationship between systemic inflammation, leukocyte counts, and systemic endotoxemia in samples from a diverse cohort of day workers and shift workers. Participants (normothermic and normotensive) were healthy volunteers, non-smoking, and drug- and medication-free. The following outcomes were measured: C-reactive protein, TNF-α, IL-6, IL-1β, IL-10, leukocyte counts (monocytes, lymphocytes, and neutrophils), and lipopolysaccharide-binding protein (LBP). Risk factors that increase systemic inflammation, such as blood pressure, sleep loss, and cortisol, were also assessed. The results indicated that shift workers slept significantly less than day workers and had significantly increased concentrations of all of the cytokines measured as well as plasma cortisol. Regression models found that after controlling for covariates, shift-work exposure predicted the significant increase observed in IL-10, leukocyte counts, and LBP. Our results suggest that acute increases in low-grade systemic endotoxemia are unresolved during chronic shift-work exposure. This ongoing immune challenge may underlie the disrupted inflammatory responses characteristic of shift-work-related pathologies. Systemic endotoxemia may represent a novel target to investigate the early effects of exposure to shift-work schedules.

Mechanical Ventilation Exacerbates Poly (I:C) Induced Acute Lung Injury: Central Role for Caspase-11 and Gut-Lung Axis

BackgroundThe mechanisms by which moderate tidal volume ventilation (MTV) exacerbates preexisting lung injury are unclear. We hypothesized that systemic endotoxemia via the gut-lung axis would lead to non-canonical and canonical inflammasome activation and pyroptosis in a two-hit model involving polyinosinic-polycytidylic acid (Poly(I:C)), a synthetic analog of dsRNA and MTV and that this would associate with acute lung injury (ALI).MethodsAnesthetized mice were administered Poly(I:C) intratracheally and then 6 h later, they were mechanically ventilated for 4 h with otherwise non-injurious MTV (10ml/kg). Changes in intestinal and alveolar capillary permeability were measured. Further documentation of ALI was assessed by evans blue albumin permeability, protein and IL-1 family concentration in bronchoalveolar lavage fluid (BALF) or plasma, and histopathology in cohorts of wildtype (WT), whole body genetically ablated caspase-11 (caspase-11-/-), caspase-1/caspase-11 double knockout (caspase-1/11-/-), gasdermin D (GSDMD)-/-, nucleotide-binding domain leucine-rich repeat-containing protein 3 (NLRP3)-/- and advanced glycosylation end product-specific receptor (RAGE) -/- mice.ResultsNon-injurious MTV exacerbated the mild lung injury associated with Poly(I:C) administration. This included the disruption of alveolar-capillary barrier and increased levels of interleukin (IL)-6, high mobility group proteins 1 (HMGB-1), IL-1β in BALF and IL-18 in plasma. Combined (Poly(I:C)-MTV) injury was associated with increase in gastrointestinal permeability and endotoxin in plasma and BALF. Poly(I:C)-MTV injury was sensitive to caspase-11 deletion with no further contribution of caspase-1 except for maturation and release of IL-18 (that itself was sensitive to deletion of NLRP3). Combined injury led to large increases in caspase-1 and caspase-11. Genetic ablation of GSDMD attenuated alveolar-capillary disruption and release of cytokines in combined injury model.ConclusionsThe previously noted exacerbation of mild Poly(I:C)-induced ALI by otherwise non-injurious MTV is associated with an increase in gut permeability resulting in systemic endotoxemia. The gut-lung axis resulted in activation of pulmonary non-canonical (cytosolic mediated caspase-11 activation) and canonical (caspase-1) inflammasome (NLRP3) mediated ALI in this two-hit model resulting in GSDMD sensitive alveolar capillary barrier disruption, pyroptosis (alveolar macrophages) and cytokine maturation and release (IL-1β; IL-18). Pharmacologic strategies aimed at disrupting communication between gut and lung, inhibition of inflammasomes or GSDMD in pyroptosis may be useful in ALI.

Leaky Gut as a Potential Culprit for the Paradoxical Dysglycemic Response to Gastric Bypass-Associated Ileal Microbiota

Altered host-intestinal microbiota interactions are increasingly implicated in the metabolic benefits of Roux-en-Y gastric bypass (RYGB) surgery. We previously found, however, that RYGB-associated ileal microbiota can paradoxically impair host glycemic control when transferred to germ-free mice. Here we present complementary evidence suggesting that this could be due to the heightened development of systemic endotoxemia. Consistently, application of ileal content from RYGB-treated compared with sham-operated rats onto Caco-2 cell monolayers compromised barrier function and decreased expression of the barrier-stabilizing proteins claudin-4 and desmoglein-2. Our findings raise the possibility that RYGB-associated ileal microbiota produce and release soluble metabolites which locally increase intestinal permeability to promote systemic endotoxemia-induced insulin resistance, with potential implications for the treatment of RYGB patients who eventually relapse onto type 2 diabetes.

Effect of Propofol and Fentanyl on Brain Oxidative Stress after Systemic Lipopolysaccharide Injection in Rats

Systemic inflammation causes brain oxidative stress, a prerequisite for neurodegeneration. In this study, we investigated the effect of the anesthetic agents propofol and fentanyl on brain oxidative stress during mild systemic endotoxemia induced by lipopolysaccharide (LPS) endotoxin. For this purpose, rats were administered LPS (400 μg/kg, intraperitoneally; i.p.), treated at the same time with different doses of propofol or fentanyl, i.p., and euthanized 4 h later. Other groups were treated with the saline, only propofol, or only fentanyl. Oxidative stress markers including malondialdehyde (MDA), nitric oxide (NO), and reduced glutathione (GSH) were determined. In addition, nuclear factor kappaB (NF-kB), paraoxonase-1 (PON-1), and butyrylcholinesterase (BChE) activities were measured in the brain tissue. Results showed that compared with the saline group, administration of LPS caused a marked and significant increase in brain MDA and NO combined with depletion of GSH and decreased PON-1 and BChE activities. Additionally, the active form of NF-kB was significantly increased in the brain of LPS only-treated rats. Treatment with propofol or fentanyl led to a marked and significant decrease in the levels of brain MDA and NO together with a significant increase in GSH and restoration of PON-1 and BChE activities. Furthermore, lower levels of active form of NF-kB were found following treatment with propofol or fentanyl compared with those in the LPS only group. Collectively, these results suggest that propofol and fentanyl exhibit an antioxidant action and attenuate the endotoxin-induced brain oxidative stress.

Endogenous intoxication associated with anesthetic preconditioning in hemorrhagic hypotension

Актуальность. Интерес к возможности уменьшения эндогенной интоксикации при острой массивной кровопотере, сопровождающей обширные сочетанные травмы и оперативные вмешательства, растёт. Феномен анестезиологического прекондиционирования обсуждается активно, так как появилась возможность дополнительной протекции различных органов и систем организма. Цель исследования: оценка параметров эндогенной интоксикации на фоне анестезиологического прекондиционирования севофлюраном при геморрагической гипотензии. Материалы и методы. Эксперимент выполнен на 100 белых беспородных крысах-самцах: 2 группы контроля (по 10 интактных животных, получавших наркоз эфиром или севофлюраном), 2 опытные группы (по 40 крыс в условиях геморрагической гипотензии на фоне наркоза эфиром или севофлюраном). Далее исследовали содержание веществ низкой и средней молекулярной массы в крови общей сонной артерии у интактных крыс и в опытных группах через 15, 30, 60 и 120 мин геморрагической гипотензии. Рассчитывали пептидно-нуклеотидный коэффициент и коэффициент ароматичности для качественной оценки пула веществ. Статистическую значимость полученных показателей определяли с использованием непараметрического критерия Манна-Уитни. Результаты. Выявлено снижение показателей эндогенной интоксикации анаболического и катаболического пулов в группах животных, получавших севофлюран. Величина пептидно-нуклеотидного коэффициента в крови была ниже только на 15-й мин геморрагической гипотензии в условиях наркоза севофлюраном, по сравнению с опытной группой крыс, получавших эфир. Заключение. У интактных животных при применении севофлюрана для анестезии эндогенная интоксикация выражена слабее, чем при использовании диэтилового эфира. В условиях геморрагической гипотензии показатели эндогенной интоксикации ниже на фоне наркоза севофлюраном, что позволяет констатировать факт системной цитопротекции, а, значит, реализацию эффекта анестезиологического прекондиционирования. Background. Interest in the possibility of reducing endogenous intoxication in acute massive blood loss is growing. The phenomenon of anesthetic preconditioning has been actively discussed since a possibility of additional protection of various organs and systems has appeared. The aim of this study was to assess parameters of endogenous intoxication associated with anesthetic preconditioning with sevoflurane in hemorrhagic hypotension. Materials and methods. Experiments were carried out on 100 white outbred male rats divided into two control groups (10 intact rats in each group anesthetized with ether or sevoflurane) and two experimental groups (40 rats in each group with hemorrhagic hypotension induced during anesthesia with ether or sevoflurane). After 15, 30, 60, and 120 min of hemorrhagic hypotension, the blood content of low and medium molecular weight substances was measured in the blood from the common carotid artery of control and experimental rats. The peptide-nucleotide coefficient and the aromaticity coefficient were calculated for qualitative assessment of the substance pool. Statistical analysis was performed with the nonparametric Mann-Whitney test. Results. Indices of endogenous intoxication of anabolic and catabolic pools were decreased in the groups receiving sevoflurane. The blood peptide-nucleotide coefficient was decreased only at 15 min of hemorrhagic hypotension during sevoflurane anesthesia compared to the experimental group receiving ether. Conclusions. In control animals anesthetized with sevoflurane for anesthesia, systemic endotoxemia was less pronounced than in the diethyl ether group. In hemorrhagic hypotension, indexes of endogenous intoxication were lower for sevoflurane anesthesia, which evidenced systemic cytoprotection, and, thus, occurrence of the effect of anesthetic preconditioning.

Mechanical Ventilation Exacerbates Poly (I:C) Induced Acute Lung Injury: Central Role for Caspase-11 and Gut-Lung Axis

Background: The mechanisms by which moderate tidal volume ventilation (MTV) may exacerbate preexisting lung injury remain unclear. We hypothesized that in two hit model (polyinosinic-polycytidylic acid (Poly(I:C)), a synthetic analog of dsRNA and MTV), systemic endotoxemia via gut-lung axis would lead to non-canonical (i.e. caspase-11 dependent) and canonical (caspase-1 dependent) inflammasome activation and programmed necrotic cell death (pyroptosis) contributing to acute lung injury (ALI) in intact mice.Methods: Anesthetized mice were administered Poly(I:C) intratracheally and then 6 h later, they were mechanically ventilated for 4 h with otherwise non-injurious MTV (10ml/kg). Changes in intestinal and alveolar capillary permeability were measured. Further documentation of ALI was assessed by evans blue albumin permeability, protein and IL-1 family concentration in bronchoalveolar lavage fluid (BALF) or plasma, and histopathology in cohorts of wildtype, whole body genetically ablated caspase-11 (caspase-11-/-), caspase-1/caspase-11 double knockout (caspase-1/11-/-), gasdermin D (GSDMD-/-), and NLRP3-/- mice. Results: Non-injurious MTV exacerbated mild Poly(I:C) lung injury including disruption of alveolar-capillary barrier and increased levels of IL-6, HMGB1, IL-1β in BALF and IL-18 in plasma. Combined (Poly(I:C)-MTV) injury was associated with increase in gastrointestinal permeability and endotoxin in plasma and BALF. Poly(I:C)-MTV injury was sensitive to caspase-11 deletion with no further contribution of caspase-1 except for maturation and release of IL-18 (that itself was sensitive to deletion of NLRP3). Combined injury led to large increases in pro-caspase-11 and its cleaved product as well as cleaved product of caspase-1. Genetic ablation of GSDMD attenuated alveolar-capillary disruption and maturation and release of cytokines in combined injury model.Conclusions: The previously noted TLR-4 independent exacerbation of mild Poly(I:C)-induced ALI by otherwise non-injurious MTV is associated with an increase in gut permeability resulting in systemic endotoxemia. The gut-lung axis resulted in activation of pulmonary non-canonical (cytosolic mediated caspase-11 activation) and canonical (caspase-1) inflammasome (NLRP3) mediated ALI in this two hit model resulting in GSDMD sensitive alveolar capillary barrier disruption, pyroptosis (in alveolar macrophages) and cytokine maturation and release (IL-1β; IL-18). Pharmacologic strategies at disrupting communication between gut and lung, inhibition of inflammasomes or effector molecule (GSDMD) in pyroptosis may be useful in ALI.

Age and gender characteristics of indicators of systemic endotoxinemia and their relationship with generally accepted laboratory risk factors for atherosclerosis

В последние годы большое внимание уделяется роли микробиоты в атерогенезе с позиций воспалительной теории. На основании экспериментальных и клинических данных была сформулирована эндотоксиновая теория атеросклероза. Подтверждением важной роли кишечного липополисахарида в атерогенезе является возрастная динамика показателей системной эндотоксинеми и липидного профиля. Цель исследования - выявление взаимосвязи между показателями системной эндотоксинемии и факторами риска атеросклероза, в аспекте возрастных и гендерных различий. Методика. Обследовано 113 пациентов среднего возраста. Все пациенты прошли оценку факторов риска развития атеросклероза по шкале SCORE. Пациенты были отнесены к средней группе риска (до 5%), оценивали себя как «здоровые», жалоб на момент обследования не предъявляли. Индекс массы тела был до 30 кг/м2. Определялись показатели липидного профиля (анализатор «StatFax 3300», США, реактивы «Analyticon», Германия): уровень общего холестерина, липопротеинов высокой плотности и уровень триглицеридов, рассчитывался индекс атерогенности и концентрация липопротеинов низкой плотности. Определялись параметры системной эндотоксинемии: концентрации липополисахарида (микро-ЛАЛ-тест), уровень антител к гидрофобной и гидрофильной частям молекулы ЛПС методом «СОИС-ИФА». Результаты. Выявлена прямая значимая корреляция концентрации общего холестерина, липопротеинов низкой плотности и липопротеинов высокой плотности в зависимости от возраста. При построении регрессионной модели зависимости показателей системной эндотоксинемии от пола и возраста пациентов не выявлено. При визуальной оценке графиков обращает внимание наличие у женщин тенденции к возрастному повышению уровня липополисахарида и снижению концентрации антител к гидрофильной части молекулы липополисахарида. Обнаружены гендерные различия показателей липидного профиля и уровня липополисахарида. Заключение. Статистически значимая возрастная динамика показателей липидного профиля при тенденции к нарастанию уровня липополисахарида, а также снижение концентрации антител к гидрофильной части молекула липополисахарида, имеющее определённые гендерные различия, свидетельствует о целесообразности продолжения исследований с увеличением числа обследованных в расширенном возрастном диапазоне. Atherosclerosis is a polyetiologic disease. In recent years, much attention has been paid to the role of the microbiota in atherogenesis from the perspective of inflammatory theory. Based on experimental and clinical data, the endotoxin theory of atherosclerosis was formulated. Confirmation of the important role of intestinal lipopolysaccharide in atherogenesis is the age dynamics of systemic endotoxemia parametrs and lipid profile. The goal of our study was to identify the relationship between the indicators of systemic endotoxemia and the generally accepted risk factors for atherosclerosis, especially the age dynamics and the influence of gender. Methods. We examined 113 patients middle age. All patients were assessed for risk factors for atherosclerosis according to the SCORE scale. Patients were assigned to the average risk group (up to 5%), rated themselves as “healthy”, did not present any complaints at the time of the survey. The body mass index was up to 30 kg/m2. Indicators of the lipid profile were determined («StatFax» 3300 analyzer, USA, «Analyticon» reagents, Germany): the level of total cholesterol, high-density lipoprotein and triglyceride levels, the atherogenic index and the concentration of low-density lipoprotein were calculated. The parameters of systemic endotoxemia were determined: the concentration of lipopolysaccharide using a micro-LAL test, the level of antibodies to the hydrophobic and hydrophilic parts of the lipopolysaccharide molecule using the “SOIS-ELISA” method. Results. A direct significant correlation was found between the concentration of total cholesterol, low-density lipoprotein and high-density lipoprotein, depending on age. When constructing a regression model of the age dynamics, the concentrations of lipopolysaccharides, antibodies to the hydrophobic and hydrophilic parts of the lipopolysaccharide molecule were not detected (p> 0.05). When adjusted for gender, the age dynamics of systemic endotoxemia was also not observed. When visually assessing the graphs, attention is drawn to the fact that women have an age-related tendency to increase the level of lipopolysaccharide and a decrease in the concentration of antibodies to the hydrophilic part of the lipopolysaccharide molecule. In addition, gender differences in lipid profile and lipopolysaccharide levels were found. Conclusion. The significant age-related dynamics of the lipid profile in the presence of a tendency to an increase in the level of lipopolysaccharide and a decrease in the concentration of antibodies to the hydrophilic part of the lipopolysaccharide molecule, which has certain gender differences, revealed the necessity and feasibility of continuing research with an increase in the number of subjects and in the extended age range.