The effects of estrogen on various organs: therapeutic approach for sepsis, trauma, and reperfusion injury. Part 2: liver, intestine, spleen, and kidney

Cardioprotective response and senescence in aged sEH null female mice exposed to LPS

Deterioration of physiological systems, like the cardiovascular system, occurs progressively with age impacting an individual's health and increasing susceptibility to injury and disease. Cellular senescence has an underlying role in age-related alterations and can be triggered by natural aging or prematurely by stressors such as the bacterial toxin lipopolysaccharide (LPS). The metabolism of polyunsaturated fatty acids by CYP450 enzymes produces numerous bioactive lipid mediators that can be further metabolized by soluble epoxide hydrolase (sEH) into diol metabolites, often with reduced biological effects. In our study, we observed age-related cardiac differences in female mice, where young mice demonstrated resistance to LPS injury, and genetic deletion or pharmacological inhibition of sEH using trans-4-[4-(3-adamantan-1-yl-ureido)-cyclohexyloxy]-benzoic acid attenuated LPS-induced cardiac dysfunction in aged female mice. Bulk RNA-sequencing analyses revealed transcriptomics differences in aged female hearts. The confirmatory analysis demonstrated changes to inflammatory and senescence gene markers such as Il-6, Mcp1, Il-1β, Nlrp3, p21, p16, SA-β-gal, and Gdf15 were attenuated in the hearts of aged female mice where sEH was deleted or inhibited. Collectively, these findings highlight the role of sEH in modulating the aging process of the heart, whereby targeting sEH is cardioprotective.NEW & NOTEWORTHY Soluble epoxide hydrolase (sEH) is an essential enzyme for converting epoxy fatty acids to their less bioactive diols. Our study suggests deletion or inhibition of sEH impacts the aging process in the hearts of female mice resulting in cardioprotection. Data indicate targeting sEH limits inflammation, preserves mitochondria, and alters cellular senescence in the aged female heart.

Sex dimorphisms in coagulation: Implications in trauma-induced coagulopathy and trauma resuscitation

Trauma-induced coagulopathy (TIC) is one of the leading causes of preventable death in injured patients. Consequently, it is imperative to understand the mechanisms underlying TIC and how to mitigate this mortality. An opportunity for advancement stems from the awareness that coagulation demonstrates a strong sex-dependent effect. Females exhibit a relative hypercoagulability compared to males, which persists after injury and confers improved outcomes. The mechanisms underlying sex dimorphisms in coagulation and its protective effect after injury have yet to be elucidated. This review explores sex dimorphisms in enzymatic hemostasis, fibrinogen, platelets, and fibrinolysis, with implications for resuscitation of patients with TIC.

Gypenoside XLIX attenuates sepsis-induced splenic injury through inhibiting inflammation and oxidative stress

BACKGROUND

To investigate the effect of Gypenoside XLIX (Gyp-XLIX) on acute splenic injury (ASI) induced by cecal ligation and puncture (CLP) in septic mice, a study was conducted.

METHODS

Sixty healthy mice were randomly divided into six groups: the NC group, the Sham group, the Sham + Gyp-XLIX group, the CLP group, the CLP + Gyp-XLIX group, and the CLP + Dexamethasone (DEX) group. The NC group did not undergo any operation, while the rest of the groups underwent CLP to establish the sepsis model. The Sham group only underwent open-abdominal suture surgery without cecum puncture. After the operation, the groups were immediately administered the drug for a total of 5 days. Various methods such as hematoxylin and eosin (HE) staining, biochemical kits, qRT-PCR, and reactive oxygen species (ROS) were used for analysis.

RESULTS

The results demonstrated that Gyp-XLIX effectively mitigated the splenic histopathological damage, while reducing the malondialdehyde (MDA) lipid peroxidation index and enhancing the antioxidant activities of catalase (CAT), glutathione (GSH) and total antioxidant capacity (T-AOC). The utilization of Dihydroethidium (DHE) fluorescent probe revealed that Gyp-XLIX inhibited the acute splenic accumulation of ROS induced by CLP in septic mice. Further investigations revealed that Gyp-XLIX exhibited a down-regulatory effect on the protein levels of inflammatory mediators iNOS and COX-2, consequently leading to the suppression of pro-inflammatory cytokines such as TNF-α, IL-6, and IL-1β. Additionally, it up-regulated the expression of anti-inflammatory factor IL-10.

CONCLUSION

In conclusion, Gyp-XLIX was significantly effective in attenuating CLP-induced acute splenic inflammation and oxidative stress in septic mice.

Multicompartmental Trauma Induces Persistent Inflammation and Organ Injury

INTRODUCTION

Previous preclinical models of multicompartmental injury have investigated its effects for durations of less than 72 h and the long-term effects have not been defined. We hypothesized that a model of multicompartmental injury would result in systemic inflammation and multiorgan dysfunction that persists at 1 wk.

METHODS

Male and proestrus female Sprague-Dawley rats (n = 16/group) underwent polytrauma (PT) (unilateral right lung contusion, hemorrhagic shock, cecectomy, bifemoral pseudofractures) and were compared to naive controls. Weight, hemoglobin, plasma neutrophil gelatinase-associated lipocalin, and plasma toll-like receptor 4 were evaluated on days two and seven. Bilateral lungs were sectioned, stained and assessed for injury at day seven. Comparisons were performed in Graphpad with significance defined as ∗P <0.05.

RESULTS

Rats who underwent PT had significant weight loss and anemia at day 2 (P = 0.001) compared to naïve rats which persisted at day 7 (P = 0.001). PT rats had elevated plasma neutrophil gelatinase-associated lipocalin at day 2 compared to naïve (P <0.0001) which remained elevated at day 7 (P <0.0001). Plasma toll-like receptor 4 was elevated in PT compared to naïve at day 2 (P = 0.03) and day 7 (P = 0.01). Bilateral lungs showed significant injury in PT cohorts at day 7 compared to naïve (P <0.0004). PT males had worse renal function at day seven compared to females (P = 0.02).

CONCLUSIONS

Multicompartmental trauma induces systemic inflammation and multiorgan dysfunction without recovery by day seven. However, females demonstrate improved renal recovery compared to males. Long-term assessment of preclinical PT models are crucial to better understand and evaluate future therapeutic immunomodulatory and anti-inflammatory treatments.

Estradiol provokes hypercoagulability and affects fibrin biology: A mechanistic exploration of sex dimorphisms in coagulation

BACKGROUND

Sex dimorphisms in coagulation are well established, with female-specific hypercoagulability conferring a survival benefit in the setting of trauma-induced coagulopathy (TIC). The mechanism behind these phenomena remains to be elucidated. We hypothesize that estradiol provokes a hypercoagulable profile and alters clot proteomics and fibrin crosslinking.

METHODS

Whole blood was collected from healthy adult volunteers (n = 30). A battery of thrombelastography (TEG) assays (native, kaolin, platelet-mapping, functional fibrinogen), whole blood thrombin generation, proteomics, and clot structure architecture (via analysis of fibrin crosslinks and fluorescent fibrinogen-visualized clots) were performed after pre-treatment of the blood with physiologic concentrations of beta-estradiol. In addition, a prospective study of coagulation through the menstrual cycle was conducted by collecting blood from women on peak and nadir estrogen days in the standard 28-day menstrual cycle.

RESULTS

On TEG, in females, estradiol provoked a hypercoagulable phenotype, specifically a shorter time to clot formation and greater thrombin generation, greater rate of clot propagation and functional fibrinogen, higher clot strength, and diminished clot fibrinolysis. In both males and females, estradiol increased platelet hyperactivity. Similar changes were seen in time to clot formation and clot strength in vivo during peak estrus of the menstrual cycle. On proteomic analysis, in both males and females, estradiol was associated with increases in abundance of several procoagulant and antifibrinolytic proteins. Crosslinking mass spectrometry analysis showed addition of estradiol increased the abundance of several FXIII crosslinks within the FIBA alpha chain in both sexes. Fluorescent fibrinogen analysis revealed a trend toward increased fiber resolvability index after addition of estradiol.

CONCLUSION

Estradiol provokes a hypercoagulable phenotype, affecting time to clot formation, clot propagation, clot strength, clot fibrinolysis, and clot structure. In sum, these data highlight the role of estradiol is driving female-specific hypercoagulability and highlights its potential role as a therapeutic adjunct in resuscitation of TIC.

Analysis of Characteristics, Pathogens and Drug Resistance of Urinary Tract Infection Associated with Long-Term Indwelling Double-J Stent

Objective

To investigate the characteristics, pathogens and drug resistance of urinary tract infection (UTI) associated with long-term indwelling double-J stent.

Methods

The clinical data of 102 patients with urinary tract infection associated with long-term indwelling double-J stent in University-Town Hospital of Chongqing Medical University and Chongqing Traditional Chinese Medicine Hospital from September 2010 to July 2022 were collected retrospectively, and the difference between etiological characteristics were analyzed. Urine and double-J stent samples of patients were collected for pathogen identification and drug sensitivity test.

Results

A total of 102 patients, 39 (38.23%) males and 63 (61.77%) females, aged 24-72 years, with a median age of 48 years, were included in this study. Urinary calculi (40.20%) and ureteral stricture (24.50%) were the main causes of urinary tract infection associated with long-term indwelling double-J stent. Among the patients with urinary tract infection caused by double-J stent, female patients were higher than male patients (61.77% vs 38.23%). In terms of positive rate of pathogenic bacteria culture, the rate of double-J stent was higher than that of urine (67.65% vs 35.29%). The main pathogenic bacteria in urine were Escherichia coli (30.55%) of Gram negative bacteria, while the main pathogenic bacteria in double-J stent were enterococcus faecalis (27.53%) of Gram positive bacteria. The resistance rate of Gram positive bacteria in double-J stent to vancomycin, ciprofloxacin, meropenem and piperacillin/tazobactam was significantly higher than that in urine (P<0.05). The resistance rate of Gram negative bacteria in double-J stent to imipenem, cefepime, piperacillin/tazobactam, meropenem and cefoperazone/sulbactam was significantly higher than that in urine (P<0.05).

Conclusion

Double-J stent associated urinary tract infection is more common in women than in men. Escherichia coli and Enterococcus faecalis are the main pathogens, and the pathogens show strong drug resistance.

SGK-1 Signalling Pathway is a Key Factor in Cell Survival in Ischemic Injury

Serum and glucocorticoid-regulated kinases (SGK) are serine/threonine kinases that belong to AGC. The SGK-1, which responds to stress, controls a range of ion channels, cell growth, transcription factors, membrane transporters, cellular enzymes, cell survival, proliferation and death. Its expression is highly controlled by various factors such as hyperosmotic or isotonic oxidative stress, cell shrinkage, radiation, high blood sugar, neuronal injury, DNA damage, mechanical stress, thermal shock, excitement, dehydration and ischemia. The structural and functional deterioration that arises after a period of ischemia when blood flow is restored is referred to as ischemia/ reperfusion injury (I/R). The current review discusses the structure, expression, function and degradation of SGK-1 with special emphasis on the various ischemic injuries in different organs such as renal, myocardial, cerebral, intestinal and lungs. Furthermore, this review highlights the various therapeutic agents that activate the SGK-1 pathway and slow down the progression of I/R injuries.

The Association of Gender and Mortality in Geriatric Trauma Patients

The association of gender with mortality in trauma remains a subject of debate. Geriatric trauma patients have a higher risk of mortality compared to younger patients. We sought to evaluate the association of gender with mortality in a group of geriatric trauma patients presenting to an academic level 1 trauma center (trauma center designated by New York State capable of handling the most severe injuries and most complex cases). Methods: We performed a retrospective review of geriatric trauma patients who were admitted to our trauma center between January 2018 and December 2020. Data collected included vital signs, demographics, injury, and clinical characteristics, laboratory data and outcome measures. The study controlled for co-morbidities, injury severity score (ISS), and systolic blood pressure (SBP) in the ED. Multivariable logistic regression analysis was performed to evaluate the association of gender and mortality. Results: 4432 geriatric patients were admitted during the study period, there were 1635 (36.9%) men and 3859 (87.2%) were White with an average age of 81 ± 8.5 years. The mean ISS was 6.7 ± 5.4 and average length of stay was 6 ± 6.3 days. There were 165 deaths. Male gender (OR 1.94, 95% CI 1.38 to 2.73), ISS (OR 1.12, 95% CI 1.09 to 1.14), Emergency Department SBP less than 90 mmHg (OR 6.17, 95% CI 3.17 to 12.01), and having more than one co-morbidity (OR 2.28, 95% CI 1.55 to 3.35) were independently predictive of death on multivariable logistic regression analysis. Conclusion: Male gender, Emergency Department systolic blood pressure less than 90 mmHg, having more than one co-morbidity, and injury severity are independent predictors of mortality among geriatric trauma patients.

Clinical features and development of Sepsis in Klebsiella pneumoniae infected liver abscess patients: a retrospective analysis of 135 cases

Background

Klebsiella pneumoniae is a primary pathogen of pyogenic liver abscess (PLA). However, little data are available on combination with sepsis. In this study, we aimed to evaluate the clinical characteristics and prognostic differences of PLA patients with sepsis.

Methods

This retrospective cohort study was conducted to investigate 135 patients with confirmed Klebsiella pneumoniae-caused liver abscesses (KPLA) from a tertiary teaching hospital, from 2013 to 2019. The patients were divided into two groups, KPLA with sepsis and KPLA without sepsis. The demographic characteristics, clinical features as well as laboratory and microbiologic findings were analyzed.

Results

A total of 135 patients with KPLA were analyzed. The mean age of patients was 60.9 ± 12.7 years, and the percentage of men was 59.3%. Among them, 37/135 (27.4%) of patients had sepsis and the mortality rate was 1.5%. The most common symptom was fever (91.1%). KPLA patients with sepsis had a significantly higher proportion of frailty, diarrhea, fatty liver, chronic renal insufficiency, and hepatic dysfunction compared to KPLA patients without sepsis (p < 0.05). Antibiotic therapy and percutaneous drainage were most frequently therapeutic strategy. Furthermore, the incidences of sepsis shock and acute respiratory distress syndrome were higher in the sepsis group compared to the non-sepsis group. As for metastatic infections, the lung was the most common site. In addition, KPLA patients with sepsis showed respiratory symptoms in 11 patients, endophthalmitis in 4 patients, and meningitis in 1 patient.

Conclusion

Our findings emphasize that KPLA patients combined with or without sepsis have different clinical features, but KPLA patients with sepsis have higher rates of complications and metastatic infections. Taken together, further surveillance and control of septic spread is essential for KPLA patients.

Estrogen As A Safe Therapeutic Adjunct in Reducing The Inflammatory Storm in Trauma Hemorrhagic Shock Patients

ABSTRACT

Trauma is a major cause of death and disability throughout the world. It is a leading cause of death with or without sepsis in about 50% of patients. Limited therapeutic options are available besides definitive care with a mortality benefit. Pre-clinical studies have demonstrated the mortality benefit of estrogen in trauma hemorrhagic shock(THS). Based on encouraging results from pre-clinical studies, we hypothesised that early administration of estrogen in male THS patients may reduce the inflammatory storm, prevent sepsis associated problems, and subsequently reduce mortality. The authors studied the safety of early administration of estrogen as a therapeutic adjunct in the emergency department (ED) and its effects on the inflammatory storm, prevention of sepsis, and mortality during the intensive care unit (ICU) stay. 40, THS patients were recruited. THS patients were divided into experimental and placebo control groups based on the estrogen administration in the ED. Serum levels of cytokines and immune cells were measured at different time points on days 0, 3, 7, and 14 in both groups of THS patients. The experimental group received intravenous estrogen (25 mg) at a single time point in the ED beside standard of care as per advanced trauma life support (ATLS) guidelines. Patients did not develop any major or minor adverse events and showed favorable clinical outcomes in the experimental group. The levels of T regulatory cells, monocytes, and systemic cytokines significantly reduced and showed a balanced inflammatory response in THS patients who received estrogen.In conclusion, this preliminary study showed that intravenous estrogen therapy is safe and reduced the inflammatory insult due to trauma hemorrhagic shock. It may protect THS patients from sepsis-associated complications. Future clinical trials are required to study the efficacy and mechanistic pathway.

Estrogen and estrogen receptors in kidney diseases

Acute kidney injury (AKI) and chronic kidney disease (CKD) are posing great threats to global health within this century. Studies have suggested that estrogen and estrogen receptors (ERs) play important roles in many physiological processes in the kidney. For instance, they are crucial in maintaining mitochondrial homeostasis and modulating endothelin-1 (ET-1) system in the kidney. Estrogen takes part in the kidney repair and regeneration via its receptors. Estrogen also participates in the regulation of phosphorus homeostasis via its receptors in the proximal tubule. The ERα polymorphisms have been associated with the susceptibilities and outcomes of several renal diseases. As a consequence, the altered or dysregulated estrogen/ERs signaling pathways may contribute to a variety of kidney diseases, including various causes-induced AKI, diabetic kidney disease (DKD), lupus nephritis (LN), IgA nephropathy (IgAN), CKD complications, etc. Experimental and clinical studies have shown that targeting estrogen/ERs signaling pathways might have protective effects against certain renal disorders. However, many unsolved problems still exist in knowledge regarding the roles of estrogen and ERs in distinct kidney diseases. Further research is needed to shed light on this area and to enable the discovery of pathway-specific therapies for kidney diseases.

Estrogen Alleviates Sex-Dependent Differences in Lung Bacterial Clearance and Mortality Secondary to Bacterial Pneumonia after Traumatic Brain Injury

Traumatic brain injury (TBI) is the leading cause of injury-related death and disability in patients under the age of 46 years. Survivors of the initial injury often endure systemic complications such as pulmonary infection, and Pseudomonas aeruginosa is one of the most common causes of nosocomial pneumonia in intensive care units. Female patients are less likely to develop secondary pneumonia after TBI, and pre-clinical studies have revealed a salutary role for estrogen after trauma. Therefore, we hypothesized that female mice would experience less mortality after post-TBI pneumonia with P. aeruginosa. We employed a mouse model of TBI followed by P. aeruginosa pneumonia. Male mice had greater mortality and impaired lung bacterial clearance after post-TBI pneumonia compared with female mice. This was confirmed as a difference in sex hormones, as oophorectomized wild-type mice had mortality and lung bacterial clearance similar to male mice. There were differences in tumor necrosis factor-α secretion in male and female alveolar macrophages after P. aeruginosa infection. Finally, injection of male or oophorectomized wild-type female mice with estrogen restored lung bacterial clearance and prevented mortality. Our model of TBI followed by P. aeruginosa pneumonia is among the first to reveal sex dimorphism in secondary, long-term TBI complications.

Neuroendocrine Modulation of the Immune Response after Trauma and Sepsis: Does It Influence Outcome?

Although the treatment of multiple-injured patients has been improved during the last decades, sepsis and multiple organ failure (MOF) still remain the major cause of death. Following trauma, profound alterations of a large number of physiological systems can be observed that may potentially contribute to the development of sepsis and MOF. This includes alterations of the neuroendocrine and the immune system. A large number of studies focused on posttraumatic changes of the immune system, but the cause of posttraumatic immune disturbance remains to be established. However, an increasing number of data indicate that the bidirectional interaction between the neuroendocrine and the immune system may be an important mechanism involved in the development of sepsis and MOF. The aim of this article is to highlight the current knowledge of the neuroendocrine modulation of the immune system during trauma and sepsis.

A rare case of double kidney stones and Emphysematous Pyelonephritis presenting with septic shock

Kidney stones and Emphysematous Pyelonephritis with septic shocks is a critical and urgent occurrence has a high mortality rate, which needs to be paid great attention to. Early anti-infection and removal of obstruction play a key role in the treatment.This case report reviews the diagnosis and treatment of the case, discusses the disease characteristics of the disease, and shares our successful clinical experience in treating the disease.

Examining the Effect of Hypertonic Saline Administered for Reduction of Intracranial Hypertension on Coagulation

BACKGROUND

Hypertonic saline (23.4%, HTS) bolus administration is common practice for refractory intracranial hypertension, but its effects on coagulation are unknown. We hypothesize that 23.4% HTS in whole blood results in progressive impairment of coagulation in vitro and in vivo in a murine model of traumatic brain injury (TBI).

STUDY DESIGN

For the in vitro study, whole blood was collected from 10 healthy volunteers, and citrated native thrombelastography was performed with normal saline (0.9%, NS) and 23.4% HTS in serial dilutions (2.5%, 5%, and 10%). For the in vivo experiment, we assessed the effects of 23.4% HTS bolus vs NS on serial thrombelastography and tail-bleeding times in a TBI murine model (n = 10 rats with TBI and 10 controls).

RESULTS

For the in vitro work, clinically relevant concentrations of HTS (2.5% dilution) shortened time to clot formation and increased clot strength (maximum amplitude) compared with control and NS. With higher HTS dosing (5% and 10% blood dilution), there was progressive prolongation of time to clot formation, decreased angle, and decreased maximum amplitude. In the in vivo study, there was no significant difference in thrombelastography measurements or tail-bleeding times after bolus administration of 23.4% HTS compared with NS at 2.5% blood volume.

CONCLUSIONS

At clinically relevant dilutions of HTS, there is a paradoxical shortening of time to clot formation and increase in clot strength in vitro and no significant effects in a murine TBI model. However, with excess dilution, caution should be exercised when using serial HTS boluses in TBI patients at risk for trauma-induced coagulopathy.

Gender differences in response to abdominal compartment syndrome in rats

Objective

Our study aims to emphasize the novelty of female rats in regard to their hemodynamic changes in response to abdominal compartment syndrome. A group of 64 rats was randomly divided into 4 subgroups for each gender. Except for the control, intra-abdominal pressure was increased to 10, 20, 30 mmHg. Survival time, mean arterial pressure, pH and lactate were determined at different time intervals.

Results

As IAP was 20 mmHg, a statistically difference was seen between the male group and the female group starting from 15 min (126 ± 9.7 mmHg, 124 ± 14.7 mmHg respectively, p < 0.02) and lasting 2 h. At 30 mmHg, a statistically difference was seen between 30 to 60 min (p < 0.05). Only group 2 presented results with statistical power both at 30 and at 60 min concerning pH (p = 0.003, p < 0.001 respectively). In the lactate measurements at IAP of 10 mmHg, at 60 min male lactate level was 3.93 ± 1.13 and 2.25 ± 0.33 in female rats (p = 0.034). Female rats that were subjected to IAP of 20 mmHg and 30 mmHg had significantly better survival than male rats that were subjected to the same pressure (p < 0.05 and p < 0.01, respectively). We concluded that female rats have better preserved their hemodynamic and metabolic parameters during ACS than male rats.

Comparison of clinical characteristics and outcomes of pyogenic liver abscess patients < 65 years of age versus ≥ 65 years of age

Background

Pyogenic liver abscess (PLA) in the elderly is insufficiently elucidated. A few studies attempted to investigate the role of age in PLA have yielded controversial results. The purpose of this study was to explore the possible differences in the comorbidity, microbiological characteristics and clinical course between elderly and young PLA patients.

Methods

The clinical data of 332 adult PLA patients who received treatment at our hospital from January 2010 to December 2016 were collected. The demographic data, etiologies, comorbidities, clinical features, laboratory results, imaging findings, microbiological characteristics, choices of treatment and clinical outcomes were analyzed.

Results

Eighty-two (24.7%) patients were older than 65 years. Comorbidities including hypertension, diabetes mellitus, and cholelithiasis were more frequently found in older patients. Elderly PLA patients were more likely to present with atypical symptoms and signs on admission. The laboratory abnormalities and imaging findings were similar between the two groups. Klebsiella pneumonia was the most common pathogen on pus culture in both groups. There were no statistically significant differences in choices of treatment, PLA-related complications and length of in-hospital stay between the two groups. And there was no in-hospital mortality.

Conclusions

The clinical characteristics were similar in young and elderly PLA patients. However, elderly PLA patients were more likely to have underlying diseases and tended to have atypical presentations. Physicians need to be vigilant when encounter possible elderly patients with PLA. However, older PLA patients had comparable outcomes as their younger counterparts. With effective treatment, both elderly and young PLA patients can be cured.

Trauma-Induced Acute X Chromosome Skewing in White Blood Cells Represents an Immuno-Modulatory Mechanism Unique to Females and a Likely Contributor to Sex-Based Outcome Differences

Sex-related outcome disparities following severe trauma have been demonstrated in human and animal studies; however, sex hormone status could not fully account for the differences. This study tested whether X-linked cellular mosaicism, which is unique to females, could represent a genetically based mechanism contributing to sex-related immuno-modulation following trauma. Serial blood samples collected for routine laboratory tests were analyzed for ChrX inactivation (XCI) ratios in white blood cells. Thirty-nine severely injured (mean ISS 19) female trauma patients on mixed racial and ethnic background were tested for initial (baseline) and trauma-induced changes in XCI ratios and their associations with severity of injury and clinical outcome. At admission, two-thirds of the patients showed XCI-ratio values between one and three, about a third presented skewed XCI ratios (3-7 range) and three patients displayed extremely skewed XCI ratios (8-30 range). Serial blood samples during the clinical course showed additional changes in XCI ratios ranging between 20% and 900% over initial. Increasing XCI ratios during the injury course correlated with the severity of trauma, subsequent need for ventilator support and pneumonia. In contrast, initial XCI ratios did not show correlations with injury severity or clinical complications. Initial XCI ratios showed a positive correlation with age but older patients retained the ability to mount trauma-induced secondary XCI changes. These data show that trauma results in X-linked cell selection in females, which is likely to be driven by polymorphic differences between the parental ChrXs. X-linked white blood cell skewing correlates with injury severity and a complicated postinjury clinical course. Female X-linked cellular mosaicism and its capacity to change dynamically during the injury course compared with the lack of this machinery in males may represent a novel immuno-modulatory mechanism contributing to sex-based outcome differences after injury and infection.

Effect of Systemic Triphenylphosphonium on Organ Function and Oxidative Stress

Conditions of systemic stress can lead to increased reactive oxygen species production, mitochondrial dysfunction, systemic inflammation, and multiorgan dysfunction. Triphenylphosphonium (TPP1) is a lipophilic cation used to target therapeutics to mitochondria. We sought to determine the effects of TPP1 on mitochondrial integrity. Male rats were anesthetized and TPP1 (5 mg/kg) or vehicle (saline) was administered intravenously 30-minutes after anesthesia initiation and intraperitoneally (20 mg/kg) 60-minutes later. Rats were exsanguinated 2-hours postinjection. Cardiac, pulmonary, hepatic, splenic, and renal tissues were analyzed for inflammation, lipid peroxidation, endogenous antioxidant activity, cytokine expression, and mitochondrial function. In vitro modeling was performed using freshly isolated hepatocytes subjected to 8-hours hypoxia/30-minutes reoxygenation in the absence or presence of TPP1. TPP1 increased lipid peroxidation in the liver, lung, and kidney as well as antioxidant activity in the liver, kidney, and spleen. Conversely, antioxidant activity decreased in the lung with TPP1. In addition, TPP1 altered hepatic inflammatory mediators. In vitro, TPP1 attenuated oxygen consumption and, when combined with hypoxic injury, depolarized mitochondrial membranes in hepatocytes. TPP1 induces systemic responses associated with oxidative stress and worsening pathologies in animals. Caution should be exercised when employing TPP1 for therapeutics.

Characterising Pre-pubertal Resistance to Death from Endotoxemia

Sepsis is a common and deadly syndrome in which a dysregulated host response to infection causes organ failure and death. The current lack of treatment options suggests that a new approach to studying sepsis is needed. Pre-pubertal children show a relative resistance to death from severe infections and sepsis. To explore this phenomenon experimentally, we used an endotoxemia model of sepsis in mice. Following intra-peritoneal injection of endotoxin, pre-pubertal mice showed greater survival than post-pubertal mice (76.3% vs. 28.6%), despite exhibiting a similar degree of inflammation after two hours. Age-associated differences in the inflammatory response only became evident at twenty hours, when post-pubertal mice showed prolonged elevation of serum cytokines and differential recruitment of peritoneal immune cells. Mechanistically, prevention of puberty by hormonal blockade or acceleration of puberty by oestrogen treatment led to increased or decreased survival from endotoxemia, respectively. Additionally, the adoptive transfer of pre-pubertal peritoneal cells improved the survival of post-pubertal recipient mice, while post-pubertal peritoneal cells or vehicle did not. These data establish a model for studying childhood resistance to mortality from endotoxemia, demonstrate that oestrogen is responsible for an increased susceptibility to mortality after puberty, and identify peritoneal cells as mediators of pre-pubertal resistance.

Inherent X-Linked Genetic Variability and Cellular Mosaicism Unique to Females Contribute to Sex-Related Differences in the Innate Immune Response

Females have a longer lifespan and better general health than males. Considerable number of studies also demonstrated that, after trauma and sepsis, females present better outcomes as compared to males indicating sex-related differences in the innate immune response. The current notion is that differences in the immuno-modulatory effects of sex hormones are the underlying causative mechanism. However, the field remains controversial and the exclusive role of sex hormones has been challenged. Here, we propose that polymorphic X-linked immune competent genes, which are abundant in the population are important players in sex-based immuno-modulation and play a key role in causing sex-related outcome differences following trauma or sepsis. We describe the differences in X chromosome (ChrX) regulation between males and females and its consequences in the context of common X-linked polymorphisms at the individual as well as population level. We also discuss the potential pathophysiological and immune-modulatory aspects of ChrX cellular mosaicism, which is unique to females and how this may contribute to sex-biased immune-modulation. The potential confounding effects of ChrX skewing of cell progenitors at the bone marrow is also presented together with aspects of acute trauma-induced de novo ChrX skewing at the periphery. In support of the hypothesis, novel observations indicating ChrX skewing in a female trauma cohort as well as case studies depicting the temporal relationship between trauma-induced cellular skewing and the clinical course are also described. Finally, we list and discuss a selected set of polymorphic X-linked genes, which are frequent in the population and have key regulatory or metabolic functions in the innate immune response and, therefore, are primary candidates for mediating sex-biased immune responses. We conclude that sex-related differences in a variety of disease processes including the innate inflammatory response to injury and infection may be related to the abundance of X-linked polymorphic immune-competent genes, differences in ChrX regulation, and inheritance patterns between the sexes and the presence of X-linked cellular mosaicism, which is unique to females.

Treatment of traumatic brain injury with 17α-ethinylestradiol-3-sulfate in a rat model

OBJECTIVE

17α-ethynylestradiol-3-sulfate (EE-3-SO4) is a highly water-soluble synthetic estrogen that has an extended half-life (∼ 10 hours) over that of naturally occurring estrogen (∼ 10 minutes). In this study, EE-3-SO4 was evaluated in a lateral fluid percussion–induced traumatic brain injury (TBI) model in rats.

METHODS

A total of 9 groups of Sprague-Dawley rats underwent craniectomy. Twenty-four hours later, lateral fluid percussion was applied to 6 groups of animals to induce TBI; the remaining 3 groups served as sham control groups. EE-3-SO4 (1 mg/kg body weight in 0.4 ml/kg body weight) or saline (vehicle control) was injected intravenously 1 hour after TBI; saline was injected in all sham animals. One day after EE-3-SO4/saline injection, intracranial pressure (ICP), cerebral perfusion pressure (CPP), and partial brain oxygen pressure (PbtO2) were measured in Groups 1–3 (2 TBI groups and 1 sham group), and brain edema, diffusion axonal injury, and cerebral glycolysis were assessed in Groups 4–6 using MRI T2 mapping, diffusion tensor imaging (DTI), and FDG-PET imaging, respectively. Four days after dosing, the open-field anxiety of animals was assessed in Groups 7–9 by measuring the duration that each animal spent in the center area of an open chamber during 4 minutes of monitoring.

RESULTS

EE-3-SO4 significantly lowered ICP while raising CPP and PbtO2, compared with vehicle treatment in TBI-induced animals (p < 0.05). The mean size of cerebral edema of TBI animals treated with EE-3-SO4 was 25 ± 3 mm3 (mean ± SE), which was significantly smaller than that of vehicle-treated animals (67 ± 6 mm3, p < 0.001). Also, EE-3-SO4 treatment significantly increased the fractional anisotropy of the white matter in the ipsilateral side (p = 0.003) and cerebral glycolysis (p = 0.014). The mean duration that EE-3-SO4-treated animals spent in the center area was 12 ± 2 seconds, which was significantly longer than that of vehicle-treated animals (4 ± 1 seconds; p = 0.008) but not different from that of sham animals (11 ± 3 seconds; p > 0.05).

CONCLUSIONS

These data support the clinical use of EE-3-SO4 for early TBI treatment.

Gender differences in outcome and use of resources do exist in Swedish intensive care, but to no advantage for women of premenopausal age

INTRODUCTION

Preclinical data indicate that oestrogen appears to play a beneficial role in the pathophysiology of and recovery from critical illness. In few previous epidemiologic studies, however, have researchers analysed premenopausal women as a separate group when addressing potential gender differences in critical care outcome. Our aim was to see if women of premenopausal age have a better outcome following critical care and to investigate the association between gender and use of intensive care unit (ICU) resources.

METHODS

On the basis of our analysis of 127,254 consecutive Simplified Acute Physiology Score III-scored Swedish Intensive Care Registry ICU admissions from 2008 through 2012, we determined the risk-adjusted 30-day mortality, accumulated nurse workload score and ICU length of stay. To investigate associations with sex, we used logistic regression and multivariate analyses on the entire cohort as well as on two subgroups stratified by median age for menopause (up to and including 45 years and older than 45 years) and six selected diagnostic subgroups (sepsis, multiple trauma, chronic obstructive pulmonary disease, acute respiratory distress syndrome, pneumonia and cardiac arrest).

RESULTS

There was no sex difference in risk-adjusted mortality for the cohort as a whole, and there was no sex difference in risk-adjusted mortality in the group 45 years of age and younger. For the group of patients older than 45 years of age, we found a reduced risk-adjusted mortality in men admitted for cardiac arrest. For the cohort as a whole, and for those admitted with multiple trauma, male sex was associated with a higher nurse workload score and a longer ICU stay.

CONCLUSIONS

Using information derived from a large multiple ICU register database, we found that premenopausal female sex was not associated with a survival advantage following intensive care in Sweden. When the data were adjusted for age and severity of illness, we found that men used more ICU resources per admission than women did.

Mesenteric lymph reperfusion exacerbates spleen injury caused by superior mesenteric artery occlusion shock

The intestinal lymph pathway plays an important role in the pathogenesis of organ injury following superior mesenteric artery occlusion (SMAO) shock. We hypothesized that mesenteric lymph reperfusion (MLR) is a major cause of spleen injury after SMAO shock. To test this hypothesis, SMAO shock was induced in Wistar rats by clamping the superior mesenteric artery (SMA) for 1 h, followed by reperfusion for 2 h. Similarly, MLR was performed by clamping the mesenteric lymph duct (MLD) for 1 h, followed by reperfusion for 2 h. In the MLR+SMAO group rats, both the SMA and MLD were clamped and then released for reperfusion for 2 h. SMAO shock alone elicited: 1) splenic structure injury, 2) increased levels of malondialdehyde, nitric oxide (NO), intercellular adhesion molecule-1, endotoxin, lipopolysaccharide receptor (CD14), lipopolysaccharide-binding protein, and tumor necrosis factor-α, 3) enhanced activities of NO synthase and myeloperoxidase, and 4) decreased activities of superoxide dismutase and ATPase. MLR following SMAO shock further aggravated these deleterious effects. We conclude that MLR exacerbates spleen injury caused by SMAO shock, which itself is associated with oxidative stress, excessive release of NO, recruitment of polymorphonuclear neutrophils, endotoxin translocation, and enhanced inflammatory responses.

Combined hemorrhage/trauma models in pigs-current state and future perspectives

The majority of injury combinations in multiply injured patients entail the chest, abdomen, and extremities. Numerous pig models focus on the investigation of posttraumatic pathophysiology, organ performance monitoring and on potential treatment options. Depending on the experimental question, previous authors have included isolated insults (controlled or uncontrolled hemorrhage, chest trauma) or a combination of these injuries (hemorrhage with abdominal trauma, chest trauma, traumatic brain injury, and/or long-bone fractures). Combined trauma models in pigs can provide a high level of clinical relevance, when they are properly designed and mimicking the clinical situation. Most of these models focus on the first hours after trauma, to assess the acute sequel of traumatic hemorrhage. However, hemorrhagic shock and the associated mass transfusion are also major causes for organ failure and mortality in the later clinical course. Thus, most models lack information on the pathomechanisms during the late posttraumatic phase. Studying new therapies only during the early phase is also not reflective of the clinical situation. Therefore, a longer observation period is required to study the effects of therapeutic approaches during intensive care treatment when using animal models. These long-term studies of combined trauma models will allow the development of valuable therapeutic approaches relevant for the later posttraumatic course. This review summarizes the existing porcine models and outlines the need for long-term models to provide real effective novel therapeutics for multiply injured patients to improve organ function and clinical outcome.

Resveratrol attenuates hypoxic injury in a primary hepatocyte model of hemorrhagic shock and resuscitation

BACKGROUND

Oxidative stress following hemorrhagic shock and resuscitation (HSR) is regulated, in part, by inflammatory and apoptotic mediators such as necrosis factor κB (NF-κB) and p53. Sirtuin 1 (Sirt-1) is a metabolic intermediary that regulates stress responses by suppressing NF-κB and p53 activity. Resveratrol is a naturally occurring polyphenolic antioxidant and Sirt-1 agonist. The aim of this study was to determine whether resveratrol protects hepatocytes following HSR or hypoxia.

METHODS

In vivo, HSR was achieved in male rats by arterial blood withdrawal to 30 ± 2 mm Hg for 1 hour before resuscitation with or without resveratrol (Res, 30 mg/kg). Hepatic tissue was stained and scored for necrosis, interleukin 6, and Sirt-1 expression. In vitro, primary rat hepatocytes were subjected to 8 hours of hypoxia without or with Res (100 µM). Cells were analyzed immediately or after 6 hours of normoxia, for survival and markers of injury (lactate dehydrogenase assay, lipid peroxidation, and mitochondrial integrity). Cell lysates were collected for cytochrome c analysis and immunoprecipitated using antibodies against NF-κB (p65) or p53.

RESULTS

In vivo, animals subject to HSR exhibited increased expression of markers of hepatocyte damage compared with those sham operated, concomitant with lower Sirt-1 expression. In vitro, hypoxia followed by normoxia resulted in increased cell death, an effect that was blunted by Res. Analysis of cell and mitochondrial function demonstrated that Res inhibited the detrimental effects of hypoxia in isolated hepatocytes.

CONCLUSION

Resveratrol prevents cell death in HSR and exerts a protective effect on the mitochondria in a hepatocyte model of hypoxic injury-reoxygenation possibly via Sirt-1 modulation of p53 and NF-κB activity.

Aldehyde dehydrogenase 1A1: friend or foe to female metabolism?

In this review, we summarize recent advances in understanding vitamin A-dependent regulation of sex-specific differences in metabolic diseases, inflammation, and certain cancers. We focus on the characterization of the aldehyde dehydrogenase-1 family of enzymes (ALDH1A1, ALDH1A2, ALDH1A3) that catalyze conversion of retinaldehyde to retinoic acid. Additionally, we propose a “horizontal transfer of signaling” from estrogen to retinoids through the action of ALDH1A1. Although estrogen does not directly influence expression of Aldh1a1, it has the ability to suppress Aldh1a2 and Aldh1a3, thereby establishing a female-specific mechanism for retinoic acid generation in target tissues. ALDH1A1 regulates adipogenesis, abdominal fat formation, glucose tolerance, and suppression of thermogenesis in adipocytes; in B cells, ALDH1A1 plays a protective role by inducing oncogene suppressors Rara and Pparg. Considering the conflicting responses of Aldh1a1 in a multitude of physiological processes, only tissue-specific regulation of Aldh1a1 can result in therapeutic effects. We have shown through successful implantation of tissue-specific Aldh1a1^−/− preadipocytes that thermogenesis can be induced in wild-type adipose tissues to resolve diet-induced visceral obesity in females. We will briefly discuss the emerging role of ALDH1A1 in multiple myeloma, the regulation of reproduction, and immune responses, and conclude by discussing the role of ALDH1A1 in future therapeutic applications.

Advances in sepsis-associated liver dysfunction

Recent studies have revealed liver dysfunction as an early event in sepsis. Sepsis-associated liver dysfunction is mainly resulted from systemic or microcirculatory disturbances, spillovers of bacteria and endotoxin (lipopolysaccharide, LPS), and subsequent activation of inflammatory cytokines as well as mediators. Three main cell types of the liver which contribute to the hepatic response in sepsis are Kupffer cells (KCs), hepatocytes and liver sinusoidal endothelial cells (LSECs). In addition, activated neutrophils, which are also recruited to the liver and produce potentially destructive enzymes and oxygen-free radicals, may further enhance acute liver injury. The clinical manifestations of sepsis-associated liver dysfunction can roughly be divided into two categories: Hypoxic hepatitis and jaundice. The latter is much more frequent in the context of sepsis. Hepatic failure is traditionally considered as a late manifestation of sepsis-induced multiple organ dysfunction syndrome. To date, no specific therapeutics for sepsis-associated liver dysfunction are available. Treatment measure is mainly focused on eradication of the underlying infection and management for severe sepsis. A better understanding of the pathophysiology of liver response in sepsis may lead to further increase in survival rates.

The liver in sepsis: patterns of response and injury

PURPOSE OF REVIEW

Sepsis elicits profound changes in the concentrations of plasma proteins synthesized by liver parenchymal cells referred to as acute-phase proteins. Mechanisms controlling this orchestrated response include release of cytokines that induce acute-phase proteins, while other 'house-keeping' genes are downregulated.

RECENT FINDINGS

Although some acute-phase proteins help to control damage, functions of many other acute-phase reactants remain obscure. Changes in acute-phase gene expression are primarily subject to transcriptional regulation and can be comprehensively monitored by array techniques. Emerging evidence from such strategies implies that in addition to a 'common host response' also highly specific pathways are induced in specific disease contexts. Applying a systems biology approach to the integrated response of the hepatocyte to infection would suggest that the reprogramming of metabolic functions occurs in parallel with a severity-dependent disruption of phase I and II biotransformation and canalicular transport, that is, excretory failure. Although traditionally bilirubin serves to monitor excretion, emerging evidence suggests that bile acids indicate liver dysfunction with higher sensitivity and specificity.

SUMMARY

Sepsis induces reprogramming of the hepatic transcriptome. This includes induction of adaptive acute-phase proteins but also repression of phase I, II metabolism and transport with important implications for monitoring and pharmacotherapy.