Increased fatty acid synthesis and disturbed lipid metabolism in Neuro2a cells after repeated cocaine exposure: A preliminary study.

Chronic use of cocaine prompts neurodegeneration and neuroinflammation. Lipids play pivotal roles in neuronal function and pathology. Although evidence correlates cocaine use with the alteration of lipid metabolism in blood and brain, the precise mechanism remains to be elucidated. In this study, we explore the effect of cocaine on neuronal fatty acid profiles in vitro. Neuro2a cells following seven days of repeated exposure to cocaine (0, 600, 800, 1000 µM) showed apoptosis-irrelevant cell death, dysregulated autophagy, activation of atypical endoplasmic reticulum stress response, increased saturated and unsaturated fatty acid synthesis, and disrupted lipid metabolism. These preliminary findings indicated the association between lipid metabolism and cocaine-induced neurotoxicity, which should be beneficial for understanding the neurotoxicity of cocaine.

Alcohol and toxicological factors influencing fatal falls from height in the Greater Tokyo Area: a retrospective study.

Falls from height pose a significant public health concern in urban regions, including the highly urbanized Greater Tokyo Area. The Japanese population is characterized by high rates of suicide and psychoactive drug usage, underscoring the importance of investigating these attributes in falls from height. This study aimed to retrospectively analyze the alcohol and toxicological aspects influencing falls from height in the Greater Tokyo Area between 2014 and 2022 and compare the findings with existing reports on other populations. In total, 75 cases of falls from height and 159 cases of natural deaths were included. Consistent with previous findings, Fisher's exact test revealed a predominance of males (66.67%, 50/75) and young adults (57.33%, 43/75) in falls from height. Multivariate logistic regression analysis identified antidepressant usage as the most significant risk factor within the target population, while younger individuals under alcohol influence constituted another high-risk group. Notably, contradictory to other populations, female individuals involved in fatal falls in the Greater Tokyo Area exhibited a higher frequency of alcohol consumption than males (48.00%, 12/25 vs. 26.00%, 13/50), and most of them were associated with suicide (83.33%, 10/12). These findings elucidate the population characteristics that pose a high risk for fatal falls from height in Japan and can serve as a reference for other Asian populations residing in similar megacities.

Comparison of perioperative outcomes and complications between intracorporeal, extracorporeal, and hybrid ileal conduit urinary diversion during robot-assisted radical cystectomy: a comparative propensity score-matched analysis from nationwide multi-institutional study in Japan.

BACKGROUND: To investigate the impact of different urinary diversion (UD) techniques on the peri- and postoperative complications of robot-assisted radical cystectomy (RARC) with ileal conduit. METHODS: We retrospectively analyzed 373 patients undergoing RARC with ileal conduit at 11 institutions in Japan between April 2018 and December 2021. Propensity score weighting was performed to adjust for confounding factors such as age, sex, body mass index, performance status, American Society of Anesthesiologists score, previous abdominal surgery, neoadjuvant chemotherapy, and preoperative high T stage (≥ cT3) and high N stage (≥ cN1). Perioperative complications were then compared among three groups: extracorporeal, intracorporeal, and hybrid urinary diversion (ECUD, ICUD, and HUD, respectively). RESULTS: A total of 150, 68, and 155 patients received ECUD, HUD, and ICUD, respectively. Bowel reconstruction time and UD time were significantly shorter in the ECUD group (p < 0.001), and console time was significantly longer and blood loss was significantly higher in the ICUD group (p < 0.001). For postoperative complications (Clavien-Dindo Classification grade ≥ 3), surgical site infection (p = 0.004), pelvic abscess (p = 0.013), anastomotic urine leak (p = 0.007), and pelvic organ prolapse (p = 0.011) significantly occurred in the ECUD group. For all grades, ileus was more common in the HUD group, whereas anastomotic stricture was more common in the ECUD group compared with the other groups (p < 0.05). CONCLUSIONS: Severe complications did not increase after HUD and ICUD compared with ECUD; however, console time tended to be longer and blood loss was slightly higher during RARC.

Enfortumab vedotin prolongs overall survival in metastatic urothelial carcinoma following pembrolizumab therapy in real-world data.

OBJECTIVE: In December 2021, enfortumab vedotin (EV), an antibody-drug conjugate directed against nectin-4, was approved in Japan as a new treatment after platinum-containing chemotherapy and PD-1/PD-L1 inhibitors. This study evaluated, using real-world data, the efficacy and safety of EV therapy in patients with metastatic urothelial carcinoma (mUC). MATERIALS AND METHODS: Fifty-five patients with mUC who discontinued pembrolizumab therapy due to disease progression between June 2018 and April 2023 at Yokohama City University Hospital were evaluated retrospectively. Of the 55 patients, 25 received EV therapy (EV group) and 30 did not (non-EV group). All patients who underwent EV therapy were diagnosed with disease progression after the approval of EV in Japan. RESULTS: The median (range) follow-up period after pembrolizumab discontinuation was 6.3 (0.7-31.1) months. There were eight (32.0%) deaths due to cancer in the EV group and 27 (90.0%) in the non-EV group. The overall survival (OS) after pembrolizumab discontinuation was not reached in the EV group versus 2.6 months in the non-EV group (p < 0.001). A multivariate analysis revealed that EV therapy (EV vs. non-EV group; hazard ratio 0.26; 95% confidence interval 0.16-0.41; p < 0.001) was an independent prognostic factor for OS. CONCLUSION: EV prolonged OS in mUC following pembrolizumab therapy in real-world data.

[A Case of Successful Treatment of Small Cell Carcinoma of the Bladder with Pembrolizumab].

Small cell carcinoma of the bladder (SCCB) is a rare cancer that accounts for approximately 1% of primary malignant bladder tumors. It is highly malignant and has a poor prognosis. Similar to small cell lung cancer, platinum-based chemotherapy is recommended as the first-line therapy, and amrubicin (AMR) is recommended as the second-line therapy, but there is no established therapy after the second line. We report a case of SCCB that was refractory to multiple chemotherapies but responded to pembrolizumab. A 77-year-old male, diagnosed with clinical stage T3N0M0 small cell carcinoma and invasive urothelial carcinoma by transurethral resection of bladder tumor (TURBT), underwent robot-assisted radical cystectomy after three cycles of neoadjuvant cisplatin-irinotecan chemotherapy, and pathological examination revealed only small cell carcinoma in his cystectomy specimen. After three courses of adjuvant carboplatin-etoposide chemotherapy, the patient developed liver and bone metastases. Furthermore, after two courses of amrubicin, we started pembrolizumab due to the progression of metastases. Metastases decreased after starting pembrolizumab and continued to decrease after discontinuation because of immunerelated adverse events (irAEs). Therefore, pembrolizumab may be an option for the treatment of refractory SCCB.

Ectopic myogenesis and fibrosis accompany adipogenesis during thymic involution induced by repeated cocaine administration.

We have shown previously that daily cocaine administration for 7-14 days in rats resulted in the acceleration of thymic involution, which is, alike to age-related thymic involution, accompanied by ectopic adipogenesis. Here we show that the thymic involution caused by repeated cocaine administration is accompanied by not only adipogenesis but also ectopic myogenesis and fibrosis. In accordance with fibrosis, we observed an increase of N-cadherin, a marker of mesenchymal cells, as well as a decrease of E-cadherin, an epithelial cell marker, in the thymus in response to cocaine administration, suggesting the occurrence of epithelial-to-mesenchymal transition (EMT). Levels of fibronectin was also increased in the thymus of cocaine group compared to control group. In addition, increases in the levels of the transcription factors for myogenic differentiation, myogenin, MYF5, and MYF6, were observed in the thymus administered cocaine for 14 days. These results indicate that the thymic involution induced by cocaine administration involves not only adipogenesis and fibrosis but also ectopic myogenesis, which is scarcely observed and rather pathological process during thymic involution.

Excessive N-acetylcysteine exaggerates glutathione redox homeostasis and apoptosis during acetaminophen exposure in Huh-7 human hepatoma cells.

Acetaminophen (APAP) hepatotoxicity is one of the biggest drawbacks of this relatively safe and widely used drug. In addition to its hepatotoxicity, APAP also cause comparable levels of toxicity on human hepatoma cells. Here we show activation of the intrinsic caspase-9/3 pathway of apoptosis followed by gasdermin E (GSDME) cleavage and subsequent ballooning in APAP (10 mM, 72 h)-treated Huh-7 human hepatocarcinoma cells. N-acetylcysteine (NAC), an antioxidant currently used as an antidote for APAP overdose, does not alleviate APAP toxicity in Huh-7 cells; NAC overdose (10 mM) rather aggravates APAP toxicity. NAC overdose not only aggravates cell death, but also decreases the cellular GSH/GSSG ratio, an indicator of redox homeostasis of glutathione. These results show for the first time that APAP-induced apoptosis in hepatoma cells is followed by secondary necrosis via the caspase-3/GSDME pathway. NAC overdose (10 mM) not only worsens the glutathione redox status, but also accelerates this pathway.

Induction of filamin-C and its involvement in the regulation of cellular senescence and apoptosis in Huh-7 hepatoma cells during arsenic trioxide exposure.

Arsenic trioxide (ATO) is one of the most toxic inorganic arsenic compounds. In this study, we examined the effects of long-term (7 days) exposure to low dose (5 µM) ATO on a human hepatocellular carcinoma cell line, Huh-7. Along with apoptosis accompanied by secondary necrosis though GSDME cleavage, we observed enlarged and flattened cells adhering to the culture dish and surviving even after exposure to ATO. An increase in cyclin-dependent kinase inhibitor p21 levels as well as positive staining for senescence-associated ß-galactosidase activity were observed in ATO-treated cells, indicating cellular senescence. Screening for both ATO-inducible proteins by MALDI-TOF-MS analysis and ATO-inducible genes by DNA microarray analysis showed a marked increase in filamin-C (FLNC), an actin cross-linking protein. Interestingly, the increase in FLNC was observed in both dead and surviving cells, suggesting that the upregulation of FLNC by ATO occurs in both apoptotic and senescent cells. Small interference RNA-mediated knock down of FLNC resulted in not only a reduction of senescence-associated enlarged morphology of the cells, but also an exacerbation of cell death. Taken together, these results suggest a regulatory role of FLNC in the execution of senescence as well as apoptosis during ATO exposure.

Cocaine induces vascular smooth muscle cells proliferation via DRP1-mediated mitochondrial fission and PI3K/HIF-1α signaling.

Long-term cocaine abuse is associated with cardiovascular and pulmonary vascular complications. The vascular toxicity of cocaine can lead to vascular remodeling characterized by excessive proliferation of vascular smooth muscle cells. Though hypoxia-inducible factor (HIF) signaling and mitochondrial fission have been suggested to play essential roles in the pathogenesis of hypoxia-induced vascular remodeling, pathogenetic mechanism for cocaine-related vascular remodeling remains to be elucidated. In this study, we explore the effect of cocaine on the proliferation of vascular smooth muscle cells by in vitro experiments. The findings indicated that the cocaine-induced vascular smooth muscle cell hyperproliferation is achieved by enhancing DRP1-mediated mitochondrial fission and activating PI3K/HIF-1α signaling. Current findings suggested that mitochondrial fission would play a pivotal role in cocaine-related vascular remodeling and would be helpful in understanding the vascular toxicity of cocaine.

Predictive factors for pentafecta achievement in robot-assisted partial nephrectomy for intermediate highly complex RENAL tumors (RENAL score ≥ 7).

OBJECTIVES: To investigate the predictive factors for pentafecta achievement of robot-assisted partial nephrectomy (RAPN) for intermediate highly complex renal tumors (RENAL score ≥ 7). METHODS: We retrospectively analyzed the data of 247 patients with renal tumors with a RENAL score ≥ 7 who underwent RAPN. Baseline characteristics and perioperative outcomes were compared between the pentafecta achieved group and the unachieved group. A multivariable logistic regression model was used to identify the predictive factors for pentafecta achievement for cT1 renal tumors with a RENAL score ≥ 7. RESULTS: Of the 247 patients, 75 (30.3%) patients were in the achieved group and 172 (69.7%) patients were in the unachieved group. The median warm ischemia time and total operation time were 18 min versus 23 min (p < 0.001) and 179 min versus 201 min (p < 0.001) in the achieved and unachieved groups, respectively. In the unachieved group, six patients (3.4%) had major perioperative complications (Clavien-Dindo classification system ≥3). The median preservation rates of estimated GFR at the 1-year postoperative period were 96.5% versus 83.0% (p < 0.001) in the achieved and unachieved groups. Multivariable logistic regression models revealed that age and tumor size were independent predictive factors for pentafecta achievement for cT1 renal tumors with a RENAL score ≥ 7. There were no significant differences in cancer-free survival between the two groups (p = 0.456). CONCLUSION: Age and tumor size were independent predictive factors for pentafecta achievement, although there was no difference in oncological outcomes between the pentafecta achieved group and the unachieved group in RAPN for cT1 renal tumors with a RENAL score ≥ 7.

[A Case of Long-Term Survival Following Multidisciplinary Therapy for Small Intestinal Metastasis of Bladder Cancer].

The patient was a 70-year-old man who underwent transurethral resection of a bladder tumor. The pathological diagnosis was urothelial carcinoma (UC) with sarcomatoid variant, ≧pT2. After neoadjuvant chemotherapy using gemcitabine and cisplatin (GC), radical cystectomy was performed. The histopathological diagnosis was no tumor remnant (ypT0ypN0). Seven months later, the patient underwent an emergency partial ileectomy for ileal occlusion, after sudden complaints of vomiting and abdominal pain and fullness. Postoperatively, two cycles of adjuvant GC chemotherapy were administered. Approximately 10 months after ileal metastasis, a mesenteric tumor appeared. After seven cycles of methotrexate/epirubicin/nedaplatin and 32 cycles of pembrolizumab therapy, the mesentery was resected. The pathological diagnosis was UC with sarcomatoid variant. No recurrence was noted for 2 years after resection of the mesentery.

Inverse regulation of GSDMD and GSDME gene expression during LPS-induced pyroptosis in RAW264.7 macrophage cells.

GSDMD and GSDME, members of the gasdermin protein family, are involved in the formation of plasma membrane channels contributing to cell rupture during a certain type of necrosis called pyroptosis. GSDMD is activated in response to immunological stimulation such as lipopolysaccharides (LPS) treatment while GSDME is mainly involved in drug-induced tumor cell death. Here we show that the expression of the GSDMD gene increases significantly during LPS-induced pyroptosis in RAW264.7 murine macrophage cells. In contrast, GSDME expression is decreased in the same cells. The increasing effect of LPS on GSDMD expression was observed only when the cells were cultured in high glucose (4.5 g/l) medium, suggesting that glucose availability is important for this effect. The effect of LPS on GSDMD expression is abolished by 2-deoxyglucose (2DG), confirming that glycolysis plays crucial roles in the increasing effect of LPS. Small interference RNA-mediated knock down of GSDMD or overexpression of GSDME causes LPS-induced pyroptosis to take place through GSDME rather than through GSDMD. Taken together, LPS regulates GSDMD and GSDME expression in opposite directions through, at least in part, its effect on glycolysis. This transcriptional regulation may contribute to the execution of pyroptosis in a GSDMD-dependent manner.

Role of Mitochondrial Dynamics in Cocaine's Neurotoxicity.

The dynamic balance of mitochondrial fission and fusion maintains mitochondrial homeostasis and optimal function. It is indispensable for cells such as neurons, which rely on the finely tuned mitochondria to carry out their normal physiological activities. The potent psychostimulant cocaine impairs mitochondria as one way it exerts its neurotoxicity, wherein the disturbances in mitochondrial dynamics have been suggested to play an essential role. In this review, we summarize the neurotoxicity of cocaine and the role of mitochondrial dynamics in cellular physiology. Subsequently, we introduce current findings that link disturbed neuronal mitochondrial dynamics with cocaine exposure. Finally, the possible role and potential therapeutic value of mitochondrial dynamics in cocaine neurotoxicity are discussed.

Contraction Band Necrosis with Dephosphorylated Connexin 43 in Rat Myocardium after Daily Cocaine Administration.

Contraction band necrosis (CBN) is a common abnormality found in the myocardium of cocaine abusers, but is rarely reported in experimental models of cocaine abuse. Connexin 43 (Cx43) is essential for cardiac intercellular communication and the propagation of CBN. Under stress or injury, cardiac Cx43 is dephosphorylated, which is related to cardiomyocyte dysfunction and pathogenesis, whereas adiponectin exerts beneficial effects in the myocardium. In this study, we explore the effects of cocaine on cardiac Cx43 in vivo. Rats were administered cocaine via the tail vein at 20 mg/kg/day for 14 days, and showed widespread CBN, microfocal myocarditis and myocardial fibrosis, corresponding to a dysfunction of cardiac mitochondria under increased oxidative stress. The increase in dephosphorylated cardiac Cx43 and its negative correlation with the myocardial distribution of CBN after cocaine administration were determined. In addition, apoptosis and necroptosis, as well as increased adiponectin levels, were observed in the myocardium after cocaine exposure. Accordingly, we found altered profiles of cardiac Cx43, CBN and its negative correlation with dephosphorylated cardiac Cx43, and the possible involvement of adiponectin in the myocardium after 14 days of cocaine administration. The latter might play a protective role in the cardiotoxicity of cocaine. The current findings would be beneficial for establishing novel therapeutic strategies in cocaine-induced cardiac consequences.

A novel prediction model for the completion of six cycles of radium-223 treatment and survival in patients with metastatic castration-resistant prostate cancer.

PURPOSE: We evaluated the predictive factors for completion of all six cycles of radium-223 (Ra-223) treatment in patients with metastatic castration-resistant prostate cancer (mCRPC). We also developed a novel prediction model for Ra-223 treatment completion using these predictors. METHODS: We retrospectively reviewed data from 122 patients with mCRPC who were treated with Ra-223. The predictive factors for the completion of six cycles of Ra-223 treatment were evaluated. Statistically significant predictive factors were then used to develop a prediction model for treatment completion. Finally, using this prediction model, we classified the overall survival (OS) of the entire cohort into three groups. RESULTS: We identified three significant variables as the predictive factors for treatment completion: baseline alkaline phosphatase (ALP) level, baseline hemoglobin (Hb) level, and baseline pain. The three groups generated using the prediction model were: group 1 (patients with three predictive factors, i.e., ALP < median, Hb ≥ median, and no pain), group 2 (patients with one to two predictive factors), and group 3 (patients without any predictive factors). The treatment completion rates differed between the three groups significantly. Furthermore, the OS also differed among the groups significantly. CONCLUSION: Our study suggested that the baseline ALP level, baseline Hb level, and baseline pain were the predictive factors of completion of all six cycles of Ra-223 treatment in patients with mCRPC. Our prediction model consisting of these factors could predict not only the completion of Ra-223 treatment, but also the post-treatment survival. This model can thus be useful for selection of patients for Ra-223 treatment.

[Malignant Peritoneal Mesothelioma Diagnosed as an Inguinal Mass : A Case Report].

Malignant peritoneal mesothelioma is generally characterized by chief complaints such as abdominal mass and abdominal pain. We report a case of malignant peritoneal mesothelioma diagnosed as an inguinal mass. A 69-year-old man was referred to our hospital complaining of abdominal distension and swelling in the right inguinal region. Abdominal/pelvic contrast-enhanced computed tomography revealed a 22 cm tumor from the right inguinal canal to the peritoneal cavity and a large amount of ascites. Because imaging analyses revealed no metastasis, we planned tumor resection. We resected the tumor with the peritoneum and right testis and sampled some nodules in the mesentery. Histopathological examination of the tumor led to the diagnosis of epithelial malignant mesothelioma. Adhering to chemotherapy guidelines for pleural malignant mesothelioma, six courses of pemetrexed and cisplatin combination chemotherapy were performed. He is alive with no evidence of new local tumor or nodules in the mesentery 1 year postoperatively.

Correlation between Automated Bone Scan Index Change after Cabazitaxel and Survival among Men with Castration-Resistant Prostate Cancer.

BACKGROUND: Automated bone scan index (aBSI) change (ΔBSI) after treatment and survival in men with prostate cancer remains unclear. We evaluated the correlation between ΔBSI after cabazitaxel and overall survival (OS) in men with bone metastatic castration-resistant prostate cancer (CRPC). METHODS: We retrospectively enrolled 32 men with bone metastatic CRPC who had received cabazitaxel. The correlation between ΔBSI from baseline to 16 weeks after starting cabazitaxel and OS was analyzed by multivariate analysis. RESULTS: Median age and time to CRPC were 70.7 years and 9.5 months, respectively. The median cycles of docetaxel before cabazitaxel were eight. Ten (31.2%) patients had visceral metastases at baseline. Median baseline prostate-specific antigen (PSA) was 123.0 ng/mL. The median aBSIs at baseline and 16 weeks after cabazitaxel were 3.2 and 4.4%, respectively. Improvements in aBSI and PSA after 16 weeks of cabazitaxel occurred in 7 (21.9%) and 12 patients (37.5%), respectively. There were no correlations between ΔBSI and OS (p = 0.55), but PSA change was significantly correlated with OS (p = 0.03) by multivariate analysis. CONCLUSIONS: This study demonstrated that ΔBSI from baseline to16 weeks after starting cabazitaxel was not correlated with OS among men with bone metastatic CRPC. Further prospective studies may be warranted to confirm the limited utility of aBSI in this setting.

Prediction of Time to Castration-Resistant Prostate Cancer Using Low-Molecular-Weight Protein Tyrosine Phosphatase Expression for Men with Metastatic Hormone-Naïve Prostate Cancer.

INTRODUCTION: Low-molecular-weight protein tyrosine phosphatase (LMW-PTP) expression affects carcinogenesis in various cancers and has been associated with determining the overall survival among men with metastatic hormone-naïve prostate cancer (mHNPC). In this study, we analyzed the value of LMWPTP for prediction of time to castration-resistant prostate cancer (CRPC) for men with mHNPC. MATERIALS AND METHODS: We retrospectively enrolled 45 men with mHNPC who were diagnosed from 2003 to 2009. All patients had received androgen deprivation therapy as first-line treatment. Prostate cancer tissues (pre-treatment needle biopsies) were immunohistochemically stained for LMW-PTP. Multivariate analyses (Cox proportional hazard model) were used to correlate baseline clinical factors of age, prostate-specific antigen (PSA), Gleason scores, T stage, N stage, extent of disease on bone scan (EOD), LMW-PTP expression and time to CRPC. Continuous variables were classified as dichotomous. RESULTS: Median age and PSA were 70.0 years and 87.8 ng/mL respectively. Median time to CRPC was 40.2 months. Median time to CRPC was significantly shorter in the high LMW-PTP group (14.8 months) than that in the low LMW-PTP group (86.3 months, p < 0.01). In multivariate analysis, age ≥70 years and high LMW-PTP expression were significant predictors of time to CRPC.

Increased circulating peroxiredoxin-4 in sepsis model rats involves secretion from hepatocytes and is mitigated by GYY4137.

Circulating peroxiredoxin-4 (Prx4) is suggested as a prognosis marker as well as a regulator of many diseases. We aimed to examine 1) whether Prx4 is secreted from the liver in an animal model of sepsis and 2) effects of GYY4137, a hydrogen sulfide donor molecule, on septic liver injury as well as the hepatic secretion of Prx4. Rats (Wistar, male, 6 weeks old) were administered lipopolysaccharide (LPS, 15 mg/kg body weight, i.p.) with or without pre-administration of GYY4137 (50 mg/kg body weight, i.p.) and sacrificed 24 h after LPS administration. Hematoxylin-eosin and Elastica Masson-Goldner stains were used to evaluate hepatic injuries. Cytokine expression levels were determined by qPCR, and the levels of Prx4 in the serum and liver were determined by immunoblotting. Hepatocytes were isolated from rat liver, and the levels of Prx4 in the medium as well as the cells were determined 24 h after the administrations of LPS (1 µg/ml), tumor necrosis factor-α (TNFα, 50 ng/ml), or interleukin-1ß (IL-1ß, 10 ng/ml), with or without GYY4137 (300 µM). Hepatic inflammation and damage in LPS-administered rats were suppressed by GYY4137. An increase in plasma Prx4 level caused by LPS was observed, but the increase was attenuated by pre-administration of GYY4137. Prx4 was secreted from isolated hepatocytes after stimulation with LPS, TNFα, or IL-1ß. GYY4137 attenuated the IL-1ß-induced Prx4 secretion from hepatocytes. Secretion from hepatocytes is likely involved in the increase in circulating Prx4 during sepsis. GYY4137 attenuates not only hepatic injury but also Prx4 secretion.

The down-regulation of cardiac contractile proteins underlies myocardial depression during sepsis and is mitigated by carbon monoxide.

The aim of this study is to investigate the mechanism underling cardiac dysfunction during sepsis, as well as the possible amelioration of this dysfunction by exogenous carbon monoxide (CO) administration. For this purpose, rats (six-week-old, male, Sprague-Dawley) were administered LPS (15 mg/kg body weight, i.p. 6 h) and/or CORM (30 mg/kg, i.p.). The decreased left ventricular ejection fraction (EF) observed in LPS group rats was recovered in the LSP + CORM group, confirming the protective role of CO against sepsis-induced myocardial depression. Proteomic as well as immunoblot analysis showed that the levels of myosin heavy and light chains (MHC and MLC) as well as α-cardiac actin (ACTC) were decreased in the LPS group, and these decreases were mitigated in the LSP + CORM group, suggesting that the amounts of major contractile proteins are decreased in depressed myocardium. Not only LPS-induced inflammatory cytokine (TNFα and IL-1ß) production but also the decrease in myofilament proteins was mitigated by CORM. These results confirm the protective action of exogenously administered CO against myocardial depression during sepsis, and reveal a novel mechanism underling cardiac dysfunction during sepsis.