Heart Transplantation in a Patient With Rheumatic Heart Disease and Severe Left Atrial Calcification.

A 62-year-old woman who had undergone mitral valve replacement 24 years ago was admitted to the hospital with congestive heart failure. She needed heart transplantation for stage D heart failure. Preoperative cardiac computed tomographic scans showed a severely calcified left atrium and a large right atrium. Given that the left atrium's calcification was too severe to suture, the calcified left atrial wall was broadly resected, and the resected left atrial wall was reconstructed with a bovine pericardial patch for anastomosis with the donor's left atrial wall. The operation was completed without heavy bleeding, and the patient was discharged from the hospital with no complications.

Comparison of Conventional Methods with Pump-Controlled Retrograde Trial off for Weaning Adults with Cardiogenic Shock from Veno-Arterial Extracorporeal Membrane Oxygenation.

Background: Pump-controlled retrograde trial off (PCRTO) is a safe, simple, and reversible method for weaning patients from veno-arterial extracorporeal membrane oxygenation (VA-ECMO). However, few studies have compared PCRTO to conventional weaning methods. This retrospective study aimed to compare PCRTO to non-PCRTO methods. Methods: This study included patients who were weaned from VA-ECMO from January 2016 to December 2022 at our medical center. Demographic data, ECMO management, ECMO complications, survival to discharge, and cardiogenic shock after VA-ECMO weaning were compared between the 2 groups. Results: Seventy patients who were weaned from VA-ECMO using PCRTO and 85 patients who were weaned with conventional methods were compared. Patient characteristics were not significantly different between the 2 groups. The rate of survival to discharge was significantly higher in the PCRTO group than in the non-PCRTO group (90% vs. 72%, p=0.01). The rates of freedom from all-cause mortality at 10, 30, and 50 days after weaning from ECMO were 75%, 55%, and 35% in the non-PCRTO group and 62%, 60%, and 58% in the PCRTO group, respectively (p=0.1). The incidence of cardiogenic shock after weaning from VA-ECMO was significantly higher in the non-PCRTO group (16% vs. 5%, p=0.04). In logistic regression analysis, PCRTO was a significant factor for survival to discharge (odds ratio, 2.42; 95% confidence interval, 1.29-5.28; p=0.02). Conclusion: Compared to conventional methods, PCRTO is a feasible and reversible method, and it serves as a useful predictor of successful VA-ECMO weaning through a preload stress test.

Endoplasmic Reticulum Stress Activates Hepatic Macrophages through PERK-hnRNPA1 Signaling.

Endoplasmic reticulum (ER) stress plays a crucial role in liver diseases, affecting various types of hepatic cells. While studies have focused on the link between ER stress and hepatocytes as well as hepatic stellate cells (HSCs), the precise involvement of hepatic macrophages in ER stress-induced liver injury remains poorly understood. Here, we examined the effects of ER stress on hepatic macrophages and their role in liver injury. Acute ER stress led to the accumulation and activation of hepatic macrophages, which preceded hepatocyte apoptosis. Notably, macrophage depletion mitigated liver injury induced by ER stress, underscoring their detrimental role. Mechanistic studies revealed that ER stress stimulates macrophages predominantly via the PERK signaling pathway, regardless of its canonical substrate ATF4. hnRNPA1 has been identified as a crucial mediator of PERK-driven macrophage activation, as the overexpression of hnRNPA1 effectively reduced ER stress and suppressed pro-inflammatory activation. We observed that hnRNPA1 interacts with mRNAs that encode UPR-related proteins, indicating its role in the regulation of ER stress response in macrophages. These findings illuminate the cell type-specific responses to ER stress and the significance of hepatic macrophages in ER stress-induced liver injury. Collectively, the PERK-hnRNPA1 axis has been discovered as a molecular mechanism for macrophage activation, presenting prospective therapeutic targets for inflammatory hepatic diseases such as acute liver injury.

Dual regulation of NEMO by Nrf2 and miR-125a inhibits ferroptosis and protects liver from endoplasmic reticulum stress-induced injury.

Rationale: The surge of severe liver damage underscores the necessity for identifying new targets and therapeutic agents. Endoplasmic reticulum (ER) stress induces ferroptosis with Gα12 overexpression. NF-κB essential modulator (NEMO) is a regulator of inflammation and necroptosis. Nonetheless, the regulatory basis of NEMO de novo synthesis and its impact on hepatocyte ferroptosis need to be established. This study investigated whether Nrf2 transcriptionally induces IKBKG (the NEMO gene) for ferroptosis inhibition and, if so, how NEMO induction protects hepatocytes against ER stress-induced ferroptosis. Methods: Experiments were conducted using human liver tissues, hepatocytes, and injury models, incorporating NEMO overexpression and Gα12 gene modulations. RNA sequencing, immunoblotting, immunohistochemistry, reporter assays, and mutation analyses were done. Results: NEMO downregulation connects closely to ER and oxidative stress, worsening liver damage via hepatocyte ferroptosis. NEMO overexpression protects hepatocytes from ferroptosis by promoting glutathione peroxidase 4 (GPX4) expression. This protective role extends to oxidative and ER stress. Similar shifts occur in nuclear factor erythroid-2-related factor-2 (Nrf2) expression alongside NEMO changes. Nrf2 is newly identified as an IKBKG (NEMO gene) transactivator. Gα12 changes, apart from Nrf2, impact NEMO expression, pointing to post-transcriptional control. Gα12 reduction lowers miR-125a, an inhibitor of NEMO, while overexpression has the opposite effect. NEMO also counters ER stress, which triggers Gα12 overexpression. Gα12's significance in NEMO-dependent hepatocyte survival is confirmed via ROCK1 inhibition, a Gα12 downstream kinase, and miR-125a. The verified alterations or associations within the targeted entities are validated in human liver specimens and datasets originating from livers subjected to exposure to other injurious agents. Conclusions: Hepatic injury prompted by ER stress leads to the suppression of NEMO, thereby facilitating ferroptosis through the inhibition of GPX4. IKBKG is transactivated by Nrf2 against Gα12 overexpression responsible for the increase of miR-125a, an unprecedented NEMO inhibitor, resulting in GPX4 induction. Accordingly, the induction of NEMO mitigates ferroptotic liver injury.

Effect of coating with combined chitosan and gallic acid on shelf-life stability of Jeju black cattle beef.

OBJECTIVE: Beef of Jeju black cattle (JBC) is considered as a healthy meat type due to its significantly higher unsaturated fatty acids (UFA). Lipid (e.g., UFA) is highly susceptible to oxidizing agents, which results in the quality deterioration and economic value loss of meat products. Therefore, development and application of novel preservative techniques is necessary to improve the shelf-life stability of high-UFA beef. The objective of this study was to assess the applicability of chitosan-based coatings in preservation of JBC beef. METHODS: Different coating solutions: 2% chitosan alone, and 2% chitosan containing 0.1% or 0.3% gallic acid were prepared to investigate their applicability in preservation of fresh beef during storage. Jeju black cattle beef (2-cm thick steaks) were non-coated (control) or coated with the above coating solutions, placed on trays, over-wrapped with plastic film and stored at 4°C. The microbiological indices, color, total volatile basic nitrogen (TVBN) and lipid oxidation of the beef were investigated after 1, 10, and 21 days of storage. RESULTS: Coating with 2% chitosan alone reduced the spoilage bacteria count, TVBN and thiobarbituric acid reactive substances levels in the beef compared with control during storage (p<0.05). Noticeably, coating with 2% chitosan containing 0.1% or 0.3% gallic acid was more effective on retardation of spoilage bacteria growth, lipid oxidation and discoloration in the beef compared to the chitosan coating alone over the storage period (21 days) (p<0.05). CONCLUSION: Taken together, the combined chitosan and gallic acid coating could be used as a bio-preservative technique in the meat industry.

Effects of Mitochondrial Transplantation on Transcriptomics in a Polymicrobial Sepsis Model.

Previously, we demonstrated that mitochondrial transplantation has beneficial effects in a polymicrobial sepsis model. However, the mechanism has not been fully investigated. Mitochondria have their own genes, and genomic changes in sepsis are an important issue in terms of pathophysiology, biomarkers, and therapeutic targets. To investigate the changes in transcriptomic features after mitochondrial transplantation in a polymicrobial sepsis model, we used a rat model of fecal slurry polymicrobial sepsis. Total RNA from splenocytes of sham-operated (SHAM, n = 10), sepsis-induced (SEPSIS, n = 7), and sepsis receiving mitochondrial transplantation (SEPSIS + MT, n = 8) samples was extracted and we conducted a comparative transcriptome-wide analysis between three groups. We also confirmed these results with qPCR. In terms of percentage of mitochondrial mapped reads, the SEPSIS + MT group had a significantly higher mapping ratio than the others. RT1-M2 and Cbln2 were identified as highly expressed in SEPSIS + MT compared with SEPSIS. Using SHAM expression levels as another control variable, we further identified six genes (Fxyd4, Apex2l1, Kctd4, 7SK, SNORD94, and SNORA53) that were highly expressed after sepsis induction and observed that their expression levels were attenuated by mitochondrial transplantation. Changes in transcriptomic features were identified after mitochondrial transplantation in sepsis. This might provide a hint for exploring the mechanism of mitochondrial transplantation in sepsis.

Total arch replacement versus hybrid operation for aortic arch aneurysm in elderly patients: a retrospective cohort analysis.

Background: There is not sufficient evidence of the superiority of hybrid procedures over total arch replacement (TAR) for the aortic arch aneurysm of an elderly patients. This retrospective study aimed to compare total arch replacement and hybrid procedures for treatment of aortic arch aneurysms in patients aged ≥75. Methods: This study was a multicenter retrospective investigation of peri-operative outcomes of patients undergoing aortic arch aneurysm repair using either TAR or hybrid procedures between January 2012 and May 2021. Risk factors for mortality were evaluated using multivariate analyses. Results: This study included 90 patients, of which 28 underwent hybrid procedures (hybrid group: frozen elephant trunk =9, zone 0 =6, zone 1 =1, zone 2 =12), and 62 underwent TAR (TAR group), and the mean duration of follow-up was 27.0±28.8 months. In patient characteristics, the incidence of chronic obstructive lung disease and chronic kidney disease in the TAR group was significantly higher than in the hybrid group, and other operative risk factors were not significantly different in both groups. No significant differences in the incidence of post-operative complications and mortality on hospitalization. Survival rates of both groups were not significantly different (P=0.31). However, re-intervention rates after aortic arch aneurysm repair were significantly higher in the hybrid group compared to the TAR group (freedom from re-intervention rates at 1, 3, 5 years: 100%, 93%, 93% in the TAR group, and 90%, 80%, 80% in the hybrid group, P=0.04). Conclusions: There was no definitive evidence of the superiority of hybrid procedures over TAR, although the risk of re-intervention was higher in the former group. The surgical strategy for aortic arch aneurysms should be selected based on the patient's demographic and anatomical characteristics.

Clinical significance of normalized airflow obstruction in patients with chronic obstructive pulmonary disease.

BACKGROUND: There is ongoing debate regarding the diagnostic criteria for chronic obstructive pulmonary disease (COPD); recent studies have focused on the early COPD detection and management. Here, we compared clinical features and prognosis in patients with FEV1/FVC<0.70 at baseline, according to normalized airflow obstruction status during follow-up. METHODS: We used the Korea COPD Subgroup Study (KOCOSS) cohort database, a prospective nationwide observational COPD study. Normalized obstruction (NO) was defined as FEV1/FVC ≥0.7 in the 2-year follow-up period, whereas fixed obstruction (FO) was defined as FEV1/FVC <0.7. Demographic and clinical data, 1-year exacerbation risk and difference in FEV1 decline over 2 years were compared between NO and FO groups. RESULTS: Among the 670 COPD patients with post-bronchodilator FEV1/FVC <0.7 in this study, 95 (14.2%) displayed NO. Compared with the FO group, the NO group had higher FEV1, and DLCO, body mass index, as well as lower Saint George Respiratory Questionnaire, Beck Depression Index, and Beck Anxiety Index. Blood eosinophil count, IgE level, and FeNO did not significantly differ between two groups. There was no significant difference in exacerbation frequency between the two groups, but the NO group had a significant increase in FEV1 compared with the FO group during follow-up. CONCLUSION: Transient airflow obstruction in the NO group may represent a clinical manifestation of early COPD; close monitoring is needed for such patients.

Is It Safe to Preserve Left Atrial Appendage During Maze Procedure?

BACKGROUND AND OBJECTIVES: The left atrial appendage (LAA) can contribute significantly to LA mechanical contraction. Nevertheless, the preventive effect of LAA occlusion during the maze procedure against cerebral infarction remains controversial. In this study, we compared the surgical, cardiac hemodynamic, and neurologic outcomes between LAA preservation and occlusion performed during the maze procedure. METHODS: Between January 2015 and August 2021, 252 patients underwent the maze procedure using cryoablation at our medical center. After excluding patients according to our exclusion criteria (i.e., mechanical prosthesis implantation, preexisting LAA thrombus), LAA was preserved in 113 patients (non-occlusion group) and occluded in 75 patients (occlusion group). Outcomes were compared using propensity score matching (PSM). RESULTS: PSM did not reveal significant intergroup differences in baseline characteristics between the non-occlusion (n=53) and occlusion (n=53) groups. During a median follow-up of 44 months, 2 patients in the non-occlusion group (3.8%) experienced ischemic strokes. There was no significant difference in the rate of freedom from stroke (p=0.19) and major adverse cardiac events (p=0.43) between the 2 groups. Through echocardiography at 1-year follow-up, a statistically significant difference in LA mechanical contraction was observed between the non-occlusion group and occlusion group (24 of 33 [72.7%] vs. 18 of 37 [48.6%], respectively; p=0.04). CONCLUSIONS: In this study, preservation of the LAA during the maze procedure resulted in better LA function than LAA occlusion, with similar rates of stroke.

Surgical Results of the Superior Vena Cava Intimal Layer-Only Suture Technique in Heart Transplantation.

Background: Superior vena cava (SVC) stenosis during follow-up is a major concern after heart transplantation, and many technical modifications have been introduced. We analyzed the surgical results of the SVC intima layer-only suture technique in heart transplantation. Methods: We performed SVC anastomosis with sutures placed only in the intima during heart transplantation. We measured the area of the SVC at 3 different points (above the anastomosis, at the anastomosis, and below the anastomosis) in an axial view by freely drawing regions of interest, and then evaluated the degree of stenosis. Patients who underwent cardiac computed tomography (CT) at 2 years postoperatively between June 2017 and May 2020 were included in this study. Results: We performed heart transplantation in 41 patients. Among them, 24 patients (16 males and 8 females) underwent follow-up cardiac CT at 2 years postoperatively. The mean age at operation was 49.4±4.9 years. The diagnoses at time of operation were dilated cardiomyopathy (n=12), ischemic heart disease (n=8), valvular heart disease (n=2), hypertrophic cardiomyopathy (n=1), and congenital heart disease (n=1). No cases of postoperative bleeding requiring intervention occurred. The mean CT follow-up duration was 1.9±0.7 years. At follow-up, the mean areas at the 3 key points were 2.7±0.8 cm2, 2.7±0.8 cm2, and 2.7±1.0 cm2 (p=0.996). There were no SVC stenosis-related symptoms during follow-up. Conclusion: The suture technique using only the SVC intimal layer is a safe and effective method for use in heart transplantation.

The Effects of Mitochondrial Transplantation on Sepsis Depend on the Type of Cell from Which They Are Isolated.

Previously, we have shown that mitochondrial transplantation in the sepsis model has immune modulatory effects. The mitochondrial function could have different characteristics dependent on cell types. Here, we investigated whether the effects of mitochondrial transplantation on the sepsis model could be different depending on the cell type, from which mitochondria were isolated. We isolated mitochondria from L6 muscle cells, clone 9 liver cells and mesenchymal stem cells (MSC). We tested the effects of mitochondrial transplantation using in vitro and in vivo sepsis models. We used the LPS stimulation of THP-1 cell, a monocyte cell line, as an in vitro model. First, we observed changes in mitochondrial function in the mitochondria-transplanted cells. Second, we compared the anti-inflammatory effects of mitochondrial transplantation. Third, we investigated the immune-enhancing effects using the endotoxin tolerance model. In the in vivo polymicrobial fecal slurry sepsis model, we examined the survival and biochemical effects of each type of mitochondrial transplantation. In the in vitro LPS model, mitochondrial transplantation with each cell type improved mitochondrial function, as measured by oxygen consumption. Among the three cell types, L6-mitochondrial transplantation significantly enhanced mitochondrial function. Mitochondrial transplantation with each cell type reduced hyper-inflammation in the acute phase of in vitro LPS model. It also enhanced immune function during the late immune suppression phase, as shown by endotoxin tolerance. These functions were not significantly different between the three cell types of origin for mitochondrial transplantation. However, only L6-mitochondrial transplantation significantly improved survival compared to the control in the polymicrobial intraabdominal sepsis model. The effects of mitochondria transplantation on both in vitro and in vivo sepsis models differed depending on the cell types of origin for mitochondria. L6-mitochondrial transplantation might be more beneficial in the sepsis model.

Surgical results of only antegrade del Nido cardioplegia infusion in conventional coronary artery bypass grafting: a retrospective study.

BACKGROUND: Additional retrograde cardioplegia infusion in conventional coronary artery bypass grafting (CABG) was introduced to address the concern of inappropriate cardioplegia delivery through the stenotic coronary artery. However, this method is complex and requires repeated infusions. Therefore, we investigated the surgical outcomes of only antegrade cardioplegia infusion in conventional CABG. METHODS: We included 224 patients who underwent isolated CABG between 2017 and 2019. The patients were divided into two groups according to the cardioplegia infusion method: antegrade cardioplegia infusion with del Nido solution (n=111, group I) and antegrade+retrograde cardioplegia infusion with blood cardioplegia solution (n=113, group II). RESULTS: The sinus recovery time after release of the aorta cross-clamp was shorter in group I (3.8±7.1 minutes, n=98) than in group II (5.8±4.1 minutes, n=73) (p=0.033). The total cardioplegia infusion volume was lower in group I (1,998.6±668.6 mL) than in group II (7,321.0±2,865.3 mL) (p<0.001). Creatine kinase-MB levels were significantly lower in group I than in group II (p=0.039). Newly developed regional wall motion abnormalities on follow-up echocardiography were detected in two patients (1.8%) in group I and five patients (4.4%) in group II (p=0.233). There was no significant difference in ejection fraction improvement between the two groups (3.3%±9.3% in group I and 3.3%±8.7% in group II, p=0.990). CONCLUSION: The only antegrade cardioplegia infusion strategy in conventional CABG is safe and has no harmful effects.

Easy surgical explantation technique for sutureless Perceval S prosthesis, 'lasso technique': a case report.

BACKGROUND: Due to structural valve deterioration of sutureless aortic prosthesis, there is a need for explantation of the prothesis. We introduce a surgical technique to explant sutureless aortic prosthesis, which has a self-expanding stent incorporated into the aortic wall. CASE PRESENTATION: An 82-year-old man who had undergone sutureless aortic valve replacement 6 years previously underwent redo-aortic and mitral valve replacement because of severe prosthetic aortic valve stenosis and mitral regurgitation. The sutureless prosthesis was explanted using 'lasso technique'. The patient was discharged after 7 days without complications. CONCLUSIONS: We presented a useful technique to explant a sutureless aortic prosthesis.

Induction of the hepatic aryl hydrocarbon receptor by alcohol dysregulates autophagy and phospholipid metabolism via PPP2R2D.

Disturbed lipid metabolism precedes alcoholic liver injury. Whether and how AhR alters degradation of lipids, particularly phospho-/sphingo-lipids during alcohol exposure, was not explored. Here, we show that alcohol consumption in mice results in induction and activation of aryl hydrocarbon receptor (AhR) in the liver, and changes the hepatic phospho-/sphingo-lipids content. The levels of kynurenine, an endogenous AhR ligand, are elevated with increased hepatic tryptophan metabolic enzymes in alcohol-fed mice. Either alcohol or kynurenine treatment promotes AhR activation with autophagy dysregulation via AMPK. Protein Phosphatase 2 Regulatory Subunit-Bdelta (Ppp2r2d) is identified as a transcriptional target of AhR. Consequently, PPP2R2D-dependent AMPKα dephosphorylation causes autophagy inhibition and mitochondrial dysfunction. Hepatocyte-specific AhR ablation attenuates steatosis, which is associated with recovery of phospho-/sphingo-lipids content. Changes of AhR targets are corroborated using patient specimens. Overall, AhR induction by alcohol inhibits autophagy in hepatocytes through AMPKα, which is mediated by Ppp2r2d gene transactivation, revealing an AhR-dependent metabolism of phospho-/sphingo-lipids.

Serial Change of Endotoxin Tolerance in a Polymicrobial Sepsis Model.

Immune suppression is known to occur during sepsis. Endotoxin tolerance is considered a mechanism of immune suppression in sepsis. However, the timing and serial changes in endotoxin tolerance have not been fully investigated. In this study, we investigated serial changes in endotoxin tolerance in a polymicrobial sepsis model. Herein, we used a rat model of fecal slurry polymicrobial sepsis. After induction of sepsis, endotoxin tolerance of peripheral blood mononuclear cells (PBMCs) and splenocytes was measured at various time points (6 h, 12 h, 24 h, 48 h, 72 h, 5 days, and 7 days), through the measurement of TNF-α production after stimulation with lipopolysaccharide (LPS) in an ex vivo model. At each time point, we checked for plasma tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-10 levels. Moreover, we analyzed reactive oxygen species (ROS) as measured by 2',7'-dichlorodihydrofluorescein, plasma lactate, serum alanine aminotransferase (ALT), and creatinine levels. Nuclear factor (NF)-κB, IL-1 receptor-associated kinase (IRAK)-M, and cleaved caspase 3 levels were measured in the spleen. Endotoxin tolerance, measured by TNF-α production stimulated through LPS in PBMCs and splenocytes, was induced early in the sepsis model, starting from 6 h after sepsis. It reached a nadir at 24 to 48 h after sepsis, and then started to recover. Endotoxin tolerance was more prominent in the severe sepsis model. Plasma cytokines peaked at time points ranging from 6 to 12 h after sepsis. ROS levels peaked at 12 h and then decreased. Lactate, ALT, and serum creatinine levels increased up to 24 to 48 h, and then decreased. Phosphorylated p65 and IRAK-M levels of spleen increased up to 12 to 24 h and then decreased. Apoptosis was prominent 48 h after sepsis, and then recovered. In the rat model of polymicrobial sepsis, endotoxin tolerance occurred earlier and started to recover from 24 to 48 h after sepsis.

True Aneurysm of the Common Coronary Button in a Marfan Patient with an Anomalous Right Coronary Artery after a Bentall Procedure: A Case Report.

True aneurysms of the coronary artery after aortic root replacement in Marfan syndrome patients are very rare. An anomalous origin of the right coronary artery (RCA) from the left sinus of Valsalva adds complexity during aortic root surgery. We present a case of a 37-year-old male patient with Marfan syndrome who had an RCA anomaly and a 4.5-cm true aneurysm of the common coronary button 14 years after a previous Bentall procedure. A redo Bentall operation and hemi-arch replacement were successfully performed. The anomalous origin of the RCA from the left sinus of Valsalva was safely divided and anastomosed as separate coronary buttons to the prosthetic composite valve graft. To prevent coronary button aneurysms after aortic root surgery in Marfan patients, the coronary buttons and the corresponding side holes on the prosthetic graft must be reduced to the maximum possible extent.

Effects of Glucocorticoid Therapy on Sepsis Depend Both on the Dose of Steroids and on the Severity and Phase of the Animal Sepsis Model.

Steroids are currently being used in sepsis, particularly in septic shock. However, clinical trials to date have shown contradictory results. This could be attributed to the different patient endotypes and steroid doses, which have also contributed to the inconclusive results. We investigated the effects of glucocorticoid therapy on sepsis in a polymicrobial sepsis model in a variety of settings, such as steroid dose, severity, and sepsis phase. We used a rat model of fecal slurry polymicrobial sepsis. First, we investigated the optimum dose of steroids in a sepsis model. We administered different doses of dexamethasone after sepsis induction (0.1DEX; 0.1 mg/kg, 0.2DEX; 0.2 mg/kg, 5DEX; 5 mg/kg). Second, we used two different severities of the fecal slurry polymicrobial sepsis rat model to examine the effects of the steroids. A moderate or severe model was defined as a survival rate of approximately 70% and 30%, respectively. Third, we administered steroids in an early (1 h after sepsis induction) or late phase (25 h after sepsis). In all the experiments, we investigated the survival rates. In the determined optimal model and settings, we measured serum lactate, alanine transferase (ALT), creatinine, tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-10, and arterial blood gas. We evaluated the bacterial burden in the blood and spleen. Endotoxin tolerance of peripheral blood mononuclear cells (PBMCs) and splenocytes was also investigated to determine the level of immune suppression 24 h after sepsis by measuring TNF-α production after stimulation with lipopolysaccharide (LPS) in an ex vivo model. Early treatment of 0.2 mg/kg dexamethasone in a severe sepsis model showed the best beneficial effects. In moderate- or late-phase sepsis, there was no survival gain with steroid treatment. DEX0.2 group showed less acute kidney injury manifested by serum creatinine and blood urea nitrogen. DEX decreased the levels of cytokines, including IL-6, IL-10, and TNF-α. Colony-forming units were significantly decreased in the blood when administered with dexamethasone. Endotoxin tolerance was not significantly different between the DEX0.2 and control groups. In conclusion, early treatment of 0.2 mg/kg dexamethasone improved the outcomes of rats in a severe sepsis model.

Gα12 overexpression in hepatocytes by ER stress exacerbates acute liver injury via ROCK1-mediated miR-15a and ALOX12 dysregulation.

Rationale: Liver injury must be further characterized to identify novel therapeutic approaches. Endoplasmic reticulum (ER) stress may cause hepatocyte death. Gα12 affects cell viability and its expression varies depending on physiological conditions. This study investigated whether hepatocyte-specific Gα12 overexpression affects acute liver injury, and if so, what the underlying mechanisms and treatment strategies are. Methods: All experiments were performed using human liver, hepatocytes, and toxicant injury models with Gna12 KO and/or hepatocyte-specific Gα12 overexpression. RNA-sequencing, immunoblotting, immunohistochemistry, reporter assays, and mutation assays were conducted. Results: Hepatic Gα12 was overexpressed in mice challenged with acetaminophen or other ER stress inducers or in patients with acute liver injury or fibrosis/cirrhosis. Several Gα12 and ER-associated pathways were identified using transcriptomic analysis. Acetaminophen intoxication was characterized by lipid peroxide-induced ferroptosis and was less severe in Gα12-deficient animals and cells. Conversely, Gα12 overexpression in wild-type or Gna12 KO hepatocytes increased hepatotoxicity, promoting lipid peroxidation, inflammation, and ferroptosis. IRE1α-dependent Xbp1 transactivated Gna12. Moreover, Gα12 overexpression enhanced the ability of acetaminophen to induce ALOX12, while downregulating GPX4. The level of miR-15a, herein identified as an ALOX12 inhibitor, was decreased. siRNA knockdown or pharmacological inhibition of ROCK1 prevented dysregulation of ALOX12 and GPX4, rescuing animals from toxicant-induced ferroptosis. These changes or correlations among the targets were confirmed in human liver specimens and datasets of livers exposed to other injurious medications. Conclusions: Gα12 overexpression by ER stress facilitates hepatocyte ferroptosis through ROCK1-mediated dysregulation of ALOX12, and miR-15a, supporting the concept that inhibition of Gα12 overexpression and/or ROCK1 axis may constitute a promising strategy for acute liver injury.

ERα inhibits mesenchymal and amoeboidal movement of liver cancer cell via Gα12.

Hepatocellular carcinoma (HCC) is the second most common cancer worldwide, demonstrating aggressiveness and mortality more frequently in men than in women. Despite reports regarding the inhibitory ability of estrogen receptor alpha (ERα, ESR1) in certain cancer progression, targets and the basis of underlying gender disparity in HCC worsening remain elusive. Here, we report the ability of ERα to transcriptionally inhibit G protein subunit alpha 12 (Gα12) responsible for HCC worsening. First, using human samples and public database, the expression of ERα and Gα12 in HCC was examined. Then, quantitative real-time PCR, chromatin immunoprecipitation-assay, luciferase assay and immunoblottings of liver cancer cell lines confirmed the inhibitory ability of ERα on Gα12 and HCC progression. Gα12 promoted mesenchymal characteristics and amoeboidal movement, which was antagonized by ERα overexpression. Additionally, we found microRNA-141 and microRNA-200a as downstream targets of the Gα12 signaling axis for cancer malignancy regulation under the control of ERα. As for in-depth mechanism, PTP4A1 was found to be directly inhibited by microRNA-141 and microRNA-200a. Moreover, we found the inhibitory effect of ERα on amoeboidal movement by analyzing the morphology and blebbing of liver cancer cells and the active form of MLC levels. The identified targets and ESR1 levels are inversely correlated with human specimens, as well as with sex-biased survival rates of HCC patients. Collectively, ERα-dependent repression of Gα12 and consequent changes in the Gα12 signaling may explain the gender disparity in HCC, providing pharmacological clues for the control of metastatic HCC.

Vertical profiles of legacy organochlorine pesticides in sediment cores from lake Nakaumi, Japan.

Two sediment core samples from the brackish Lake Nakaumi in Japan were analyzed to determine the historical profiles of organochlorine pesticides (OCPs). It was observed that from the 1940s to 2005, the vertical distribution of OCPs in sediment cores reflected the temporal trend of pesticide usage in Japan. Dichlorodiphenyltrichloroethane (DDT) and its metabolites were predominant, with concentrations of 0.008-8.27 ng g-1 dry weight, and their contribution to ΣOCPs was over 58%. The results also confirmed that the DDTs in the sediment cores originated from past input. Further, even though hexachlorocyclohexanes were the most used OCP in Japan, their residual concentrations were lower than those of DDTs and chlordane related compounds (CHLs). The concentrations of CHLs were 0.163-1.539 ng g-1 dry weight, whereas hexachlorobenzene (HCB), drins, heptachlor, and mirex showed very low concentrations. Interestingly, although HCB was never registered as a pesticide in Japan, it was detected in both core samples. This HCB contamination might be attributed to pentachlorophenol. Additionally, the hierarchical cluster analysis results corresponding to both sediment cores could be classified under four groups based on a similarity of over 50%. The results also showed that the OCP burden in Lake Nakaumi for the past 60 years was 130 kg and 1153 kg at Honjo and at the center of Lake Nakaumi, respectively. Overall, the results of this study indicate that the distribution of OCPs in Lake Nakaumi reflects the trend of pesticide usage in Japan.