[The applications and challenges of combined monitoring of macro/micro-circulation and mitochondrial homeostasis in early warning of perioperative organ injury]

Perioperative organ injury is a leading risk factor for mortality in surgical patients. Given the current limitations in the timeliness and accuracy of markers for perioperative organ injury, this article proposes a comprehensive early-warning assessment system that jointly monitors the macro-circulation, micro-circulation, and mitochondrial homeostasis. Macro-circulation monitoring allows for real-time evaluation of key indicators such as blood pressure and cardiac output, while micro-circulation monitoring aids in assessing the status of microvascular perfusion. Monitoring of mitochondrial homeostasis provides timely insights into cellular energy metabolism. These three facets are interconnected and collectively determine the balance between tissue oxygenation and energy supply and demand. This article will elucidate commonly used monitoring methods and clinically valuable assessment models within this system, offering theoretical and technical guidance to deepen our understanding of the pathological processes of perioperative organ injury, enhance surgical safety and success rates, and improve patient prognosis and quality of life.

Multifaceted functions of Drp1 in hypoxia/ischemia-induced mitochondrial quality imbalance: from regulatory mechanism to targeted therapeutic strategy

Hypoxic-ischemic injury is a common pathological dysfunction in clinical settings. Mitochondria are sensitive organelles that are readily damaged following ischemia and hypoxia. Dynamin-related protein 1 (Drp1) regulates mitochondrial quality and cellular functions via its oligomeric changes and multiple modifications, which plays a role in mediating the induction of multiple organ damage during hypoxic-ischemic injury. However, there is active controversy and gaps in knowledge regarding the modification, protein interaction, and functions of Drp1, which both hinder and promote development of Drp1 as a novel therapeutic target. Here, we summarize recent findings on the oligomeric changes, modification types, and protein interactions of Drp1 in various hypoxic-ischemic diseases, as well as the Drp1-mediated regulation of mitochondrial quality and cell functions following ischemia and hypoxia. Additionally, potential clinical translation prospects for targeting Drp1 are discussed. This review provides new ideas and targets for proactive interventions on multiple organ damage induced by various hypoxic-ischemic diseases.

Activated Drp1 regulates p62-mediated autophagic flux and aggravates inflammation in cerebral ischemia-reperfusion via the ROS-RIP1/RIP3-exosome axis

BACKGROUND

Cerebral ischemia-reperfusion injury (CIRI) refers to a secondary brain injury that can occur when the blood supply to the ischemic brain tissue is restored. However, the mechanism underlying such injury remains elusive.

METHODS

The 150 male C57 mice underwent middle cerebral artery occlusion (MCAO) for 1 h and reperfusion for 24 h, Among them, 50 MCAO mice were further treated with Mitochondrial division inhibitor 1 (Mdivi-1) and 50 MCAO mice were further treated with N-acetylcysteine (NAC). SH-SY5Y cells were cultured in a low-glucose culture medium for 4 h under hypoxic conditions and then transferred to normal conditions for 12 h. Then, cerebral blood flow, mitochondrial structure, mitochondrial DNA (mtDNA) copy number, intracellular and mitochondrial reactive oxygen species (ROS), autophagic flux, aggresome and exosome expression profiles, cardiac tissue structure, mitochondrial length and cristae density, mtDNA and ROS content, as well as the expression of Drp1-Ser616/Drp1, RIP1/RIP3, LC3 II/LC3 I, TNF-α, IL-1β, etc., were detected under normal or Drp1 interference conditions.

RESULTS

The mtDNA content, ROS levels, and Drp1-Ser616/Drp1 were elevated by 2.2, 1.7 and 2.7 times after CIRI (P < 0.05). However, the high cytoplasmic LC3 II/I ratio and increased aggregation of p62 could be reversed by 44% and 88% by Drp1 short hairpin RNA (shRNA) (P < 0.05). The low fluorescence intensity of autophagic flux and the increased phosphorylation of RIP3 induced by CIRI could be attenuated by ROS scavenger, NAC (P < 0.05). RIP1/RIP3 inhibitor Necrostatin-1 (Nec-1) restored 75% to a low LC3 II/LC3 I ratio and enhanced 2 times to a high RFP-LC3 after Drp1 activation (P < 0.05). In addition, although CIRI-induced ROS production caused no considerable accumulation of autophagosomes (P > 0.05), it increased the packaging and extracellular secretion of exosomes containing p62 by 4 - 5 times, which could be decreased by Mdivi-1, Drp1 shRNA, and Nec-1 (P < 0.05). Furthermore, TNF-α and IL-1β increased in CIRI-derived exosomes could increase RIP3 phosphorylation in normal or oxygen-glucose deprivation/reoxygenation (OGD/R) conditions (P < 0.05).

CONCLUSIONS

CIRI activated Drp1 and accelerated the p62-mediated formation of autophagosomes while inhibiting the transition of autophagosomes to autolysosomes via the RIP1/RIP3 pathway activation. Undegraded autophagosomes were secreted extracellularly in the form of exosomes, leading to inflammatory cascades that further damaged mitochondria, resulting in excessive ROS generation and the blockage of autophagosome degradation, triggering a vicious cycle.

Characteristics of aerosol optical depth dynamics and their causes over typical cities along the 21st Century Maritime Silk Road

Atmospheric aerosols, i.e., suspension of liquid and/or solid particles in air, have serious impacts on human health. Exploring the variation and patterns of regional atmospheric aerosols is of great significance to monitor and evaluate atmosphere quality, especially in urban areas with large population. Here, with nine typical pivotal cities along the 21st Century Maritime Silk Road through Southeast Asia, South Asia to West Asia as case studies, based on MCD19A2 550 nm AOD products, combined meteorological factors, land use data, and nighttime light data, we analyzed the spatio-temporal distribution, variation features, influencing and/or driving factors of aerosols in developed urban areas over Asia. The results showed that the descending sequence of the annual aerosol optical depth (AOD) of the nine cities was Karachi, Doha, Chittagong, Bangkok, Colombo, Ho Chi Minh, Singapore, Gwadar, and Yangon during 2013-2018. Due to the influence of regional climate system and atmospheric aerosol types, the time series of annual, seasonal, and monthly AODs were significantly different. The high values of AODs in most cities were mainly located in the urban center or rapid socio-economic (e.g., industrial and agricultural) development regions. The effects of different meteorological factors on the AODs varied in different cities. The rainfall, relative humidity, and wind speed had great impacts on AODs in Ho Chi Minh, Bangkok, Singapore, and Yangon. Temperature, relative humidity, and wind speed had close correlations with AODs in Chittagong, Colombo, Karachi, and Gwadar of South Asia and Doha in West Asia. The urban area's AOD was influenced by the combined and synergistic effects of socio-economy, urbanization, and meteorological factors, with that in Karachi being the most significant.

Regulatory mechanisms, prophylaxis and treatment of vascular leakage following severe trauma and shock

Vascular leakage, or increased vascular permeability, is a common but important pathological process for various critical diseases, including severe trauma, shock, sepsis, and multiple organ dysfunction syndrome (MODS), and has become one of the most important causes of death for intensive care units (ICU) patients. Currently, although there has been some progress in knowledge of the pathogenesis of these vascular disorders, the detailed mechanisms remain unclear, and effective prophylaxis and treatment are still lacking. In this study, we aimed to provide a review of the literature regarding the regulatory mechanisms and prophylaxis as well as the treatment of vascular leakage in critical diseases such as severe trauma and shock, which could be beneficial for the overall clinical treatment of vascular leakage disorders.

Prognostic role of tumor PIK3CA mutation in colorectal cancer: a systematic review and meta-analysis

BACKGROUND

Somatic mutations in the phosphatidylinositol-4,5-bisphosphate 3-kinase/AKT pathway play a vital role in carcinogenesis. Approximately 15%-20% of colorectal cancers (CRCs) harbor activating mutations in PIK3CA, making it one of the most frequently mutated genes in CRC. We thus carried out a systematic review and meta-analysis investigating the prognostic significance of PIK3CA mutations in CRC.

MATERIALS AND METHODS

Electronic databases were searched from inception through May 2015. We extracted the study characteristics and prognostic data of each eligible study. The hazard ratio (HR) and 95% confidence interval (CI) were derived and pooled using the random-effects Mantel-Haenszel model.

RESULTS

Twenty-eight studies enrolling 12 747 patients were eligible for inclusion. Data on overall survival (OS) and progression-free survival (PFS) were available from 19 and 10 studies, respectively. Comparing PIK3CA-mutated CRC patients with PIK3CA-wild-type CRC patients, the summary HRs for OS and PFS were 0.96 (95% CI 0.83-1.12) and 1.20 (95% CI 0.98-1.46), respectively. The trim-and-fill, Copas model and subgroup analyses stratified by the study characteristics confirmed the robustness of the results. Five studies reported the CRC prognosis for PIK3CA mutations in exons 9 and 20 separately; neither exon 9 mutation nor exon 20 mutation in PIK3CA was significantly associated with patient survival.

CONCLUSIONS

Our findings suggest that PIK3CA mutation has the neutral prognostic effects on CRC OS and PFS. Evidence was accumulating for the establishment of CRC survival between PIK3CA mutations and patient-specific clinical or molecular profiles.

Growth and acid production of Lactobacillus delbrueckii ssp. bulgaricus ATCC 11842 in the fermentation of algal carcass

Algal carcass is a low-value byproduct of algae after its conversion to biodiesel. Dried algal carcass is rich in protein, carbohydrate, and multiple amino acids, and it is typically well suited for growth and acid production of lactic acid bacteria. In this study, Lactobacillus delbrueckii ssp. bulgaricus ATCC 11842 was used to ferment different algal carcass media (ACM), including 2% ACM, 2% ACM with 1.9% glucose (ACM-G), and 2% ACM with 1.9% glucose and 2g/L amino acid mixture (ACM-GA). Concentrations of organic acids (lactic acid and acetic acid), acetyl-CoA, and ATP were analyzed by HPLC, and activities of lactate dehydrogenase (LDH), acetokinase (ACK), pyruvate kinase (PK), and phosphofructokinase (PFK) were determined by using a chemical approach. The growth of L. bulgaricus cells in ACM-GA was close to that in the control medium (de Man, Rogosa, and Sharpe). Lactic acid and acetic acid contents were greatly reduced when L. bulgaricus cells were grown in ACM compared with the control medium. Acetyl-CoA content varied with organic acid content and was increased in cells grown in different ACM compared with the control medium. The ATP content of L. bulgaricus cells in ACM was reduced compared with that of cells grown in the control medium. Activities of PFK and ACK of L. bulgaricus cells grown in ACM were higher and those of PK and LDH were lower compared with the control. Thus, ACM rich in nutrients may serve as an excellent substrate for growth by lactic acid bacteria, and addition of appropriate amounts of glucose and amino acids can improve growth and acid production.

Effect of different anesthesia methods on erythrocyte immune function in mice

OBJECTIVE

To explore effect of different anesthesia methods and different anesthetics on erythrocyte immune function in mice.

METHODS

The mice were anesthetized by isoflurane and ether inhalation, and also under intraperitoneal anesthesia with sodium pentobarbital and chloral hydrate. Blood was collected from the ventro-cardinal vein. Automatic blood cell analyzer was used for routine blood examination, and the canthine oxidase method was used to measure the superoxide dismutase (SOD) activity. Lipid peroxidation product malondialdehyde (MDA) was measured with TBA, and glutathione peroxidase (GSH-Px) was measured with DTNB, and then the effect of different anesthesia methods and different anesthetics on erythrocyte immune function in mice was observed.

RESULTS

Hct level of chloral hydrate intraperitoneal injection group was significantly higher than the other three groups (P<0.05). And the MDA levels in the pentobarbital sodium group were significantly higher than the other three groups (P<0.05). SOD and GSH-Px of the chloral hydrate and sodium pentobarbital intraperitoneal injection group were significantly lower than the other two groups; RBC-C 3bRR and RBC-ICR of the chloral hydrate and sodium pentobarbital intraperitoneal injection group were significantly lower than the other two groups.

CONCLUSIONS

Different drugs can induce changes in immune function of mice at different levels. Isoflurane and ether have less damage to animal body, while chloral hydrate and sodium pentobarbital intraperitoneal injection have a certain inhibitory effect on the animal body respiratory system and can cause greater damage to the body. Therefore, the reasonable selection and control of anesthetics are very important in order to avoid the experimental errors caused by anesthesia.

Unfolded protein response suppresses cisplatin-induced apoptosis via autophagy regulation in human hepatocellular carcinoma cells

It has been shown that drug resistance is extremely common in hepatocellular carcinoma (HCC) and is one of the major problems in HCC chemotherapy. However, the detailed mechanisms remain largely unknown. We have previously shown that endoplasmic reticulum (ER) stress is involved in the tumorigenesis of HCC. Here, we demonstrated that the unfolded protein response (UPR) inhibits cisplatin-induced HCC cell apoptosis. In HCC cells, cisplatin treatment triggers the UPR, which subsequently inhibits cisplatin-induced apoptosis. Importantly, mild ER stress precondition suppresses the sensitivity of HCC cells to cisplatin-induced apoptosis through autophagy regulation. Furthermore, heat-shock protein 27 (Hsp27) is involved in the cytoprotective role of the UPR in cisplatin-induced apoptosis. We also demonstrated that Hsp27 inhibits cisplatin- induced HCC cell death through autophagy activation. Taken together, our results indicate that the UPR inhibits cisplatin-induced apoptosis in HCC cells, at least in part, by Hsp27-mediated autophagy activation.

PI3K/Akt promotes GRP78 accumulation and inhibits endoplasmic reticulum stress-induced apoptosis in HEK293 cells

The potential pro-survival role of phosphatidylinositol 3-kinase (PI3K)/Akt during endoplasmic reticulum stress has been well-characterized. However, the detailed mechanisms remain largely unknown. Here, we showed that PI3K/Akt inhibition promoted endoplasmic reticulum stress-induced apoptosis in a glucose-regulated protein 78 (GRP78)-dependent manner. During endoplasmic reticulum stress, high levels of Akt phosphorylation were sustained for at least 18 h in HEK293 cells. Importantly, PI3K/Akt enhanced GRP78 accumulation through increasing its stability following endoplasmic reticulum stress. Furthermore, Akt1, but not Akt2 or Akt3, was involved in GRP78 stability regulation. These results suggest that PI3K/Akt inhibits endoplasmic reticulum stress-induced apoptosis in HEK293 cells, at least in part, by promoting GRP78 protein stability.

Synthesis, crystal structure and properties of a new dinuclear manganese(III) complex: a mimic for catalase

A new dinuclear manganese (III) complex [(ac)Mn(bbml)(2)Mn(ac)] x (BF(4))(2) x 3.5H(2)O (Hbbml=[bis(2-benzimidazolylmethyl)amino]ethanol, Hac=acetic acid) was synthesized and characterized by several physical methods. X-ray structure analysis shows that the complex has a dimeric unit and the two Mn(III) atoms are bridged by the oxygen atoms of the two ligands, forming a bis (micro-alkoxo)dimanganese core. The Mn-Mn distance is 3.2103 A. Electrospray mass spectrometry (ES-MS) experiment shows that the complex cation may easily have lost one or two ac(-) and leave unoccupied coordination site which would favor the coordination and activation of hydrogen peroxide. Furthermore, its catalytic activity for the disproportionation of hydrogen peroxide and the effect of added heterocyclic base were also investigated. The complex has some similarities to manganese catalase in structure and activity.

Ezrin-radixin-moesin-binding phosphoprotein 50 is expressed at the apical membrane of rat liver epithelia

Ezrin-radixin-moesin (ERM)-binding phosphoprotein 50 (EBP50) and NHE3 Kinase A regulatory protein (E3KARP) are membrane-cytoskeleton linking proteins that utilize 2 PSD-95/DIg/ZO-1 (PDZ) domains and an ERM binding site to coordinate cyclic adenosine monophosphate (cAMP)-regulated ion transport in a number of distinct epithelia. ERM family members serve to anchor EBP50 and E3KARP to the actin cytoskeleton and sequester protein kinase A (PKA) to these protein complexes. In hepatocytes and cholangiocytes, the epithelial cells of the bile secretory unit, cAMP-activated PKA stimulates secretion and bile formation, but the molecular mechanisms, including the potential contribution of EBP50 and E3KARP, remain undetermined. The present studies evaluated the comparative expression and localization of EBP50 and E3KARP in rat hepatocytes and cholangiocytes. Complementary DNAs encoding rat EBP50 and E3KARP were identified by reverse transcription-polymerase chain reaction in both epithelial cell types and subsequently sequenced. Northern and Western analysis showed the presence of EBP50 messenger RNA and protein in both hepatocytes and cholangiocytes. Confocal immunofluorescence revealed EBP50 was concentrated at the apical domain of both cell types. E3KARP was also expressed in cholangiocytes but had a distinct cytoplasmic/nuclear distribution. In dominant-negative transfection studies, patch clamp analysis of Mz-ChA1 cholangiocarcinoma cells showed that expression of the PDZ1 domain of EBP50 selectively decreased the endogenous cAMP-mediated Cl secretory response. The apical expression of EBP50, presence of specific ERM proteins, and functional effects of PDZ1 expression on cholangiocyte secretion suggest EBP50 is positioned to contribute to the organization and regulation of bile secretory proteins in both hepatocytes and cholangiocytes.

Terephthalaldehyde bis(thiosemicarbazone) bis(dimethylformamide) solvate

The thiosemicarbazone molecule in C(10)H(12)N(6)S(2).2C(3)H(7)NO has -1 symmetry. The thiosemicarbazone moiety and the benzene ring are essentially coplanar, with mean and maximum deviations of 0.03 and 0. 11 A, respectively. The dimethylformamide molecules bridge the thiosemicarbazone moieties, forming two-dimensional sheets through N-H.O hydrogen bonds.