An Effective Method to Prepare Curcumin-Loaded Soy Protein Isolate Nanoparticles Co-Stabilized by Carrageenan and Fucoidan.

In this study, a novel and simple strategy is proposed based on 3D network formed by easily blending polysaccharide carrageenan (Car) and fucoidan (Fuc) without a crosslinker. The Fuc/Car dual coating effectively assists the self-assembly of soy protein-isolated (SPI)/curcumin (Cur, C) composite microcapsules (SPI/C) and achieves an excellent curcumin encapsulation efficiency (EE) up to 95.28% with a 4.16% loading capacity (LC) under optimal conditions. The resulting nanocomposites achieved a satisfying redispersibility in aqueous solution and enhanced the water solubility with a lower size dispersity index (PDI) of 0.12 and a larger zeta potential of -29.67 mV. The Fuc/Car double-layer network not only dramatically improved its thermal stability and photostability, but also provided controlled release and enhanced antioxidant activity in in vitro conditions. The underlying mechanism of the self-assembly of the curcumin-loaded nanoparticles was also addressed. The results proved the feasibility of the encapsulation of unstable hydrophobic bioactive substances (curcumin) with the dual anionic polysaccharide Fuc/Car co-stabilized SPI nanoparticles. This study paves the way for an alternative way of developing novel curcumin delivery systems and will have broad prospects in the pharmaceutical industries.

A Lipopolysaccharide O-Antigen Synthesis Gene in Mesorhizobium huakuii Plays Differentiated Roles in Root Nodule Symbiotic Compatibility with Astragalus sinicus.

Lipopolysaccharide (LPS) is a ubiquitous microbial-associated molecular pattern. Plants can sense the three components of LPS, including core polysaccharide, lipid A, and O-antigen. LPS biosynthesis is an essential factor for the successful establishment of symbiosis in the rhizobium-legume plant system. The MCHK_1752 gene (Mesorhizobium huakuii 7653R gene) encodes O-antigen polymerase and affects the synthesis of O-antigen. Here, we investigated the symbiotic phenotypes of six Astragalus sinicus accessions inoculated with the MCHK_1752 deletion mutant strain. The results revealed that the MCHK_1752 deletion mutant strain had a suppressing effect on the symbiotic nitrogen fixation of two A. sinicus accessions, a promoting effect in three A. sinicus accessions, and no significant effect in one A. sinicus accessions. In addition, the effect of MCHK_1752 on the phenotype was confirmed by its complementary strains and LPS exogenous application. Deletion of MCHK_1752 showed no effect on the growth of a strain, but affected biofilm formation and led to higher susceptibility to stress in a strain. At the early symbiotic stage, Xinzi formed more infection threads and nodule primordia than Shengzhong under inoculation with the mutant, which might be an important reason for the final symbiotic phenotype. A comparison of early transcriptome data between Xinzi and Shengzhong also confirmed the phenotype at the early symbiotic stage. Our results suggest that O-antigen synthesis genes influence symbiotic compatibility during symbiotic nitrogen fixation. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

IGF2BP3 promotes adult myocardial regeneration by stabilizing MMP3 mRNA through interaction with m6A modification.

Myocardial infarction that causes damage to heart muscle can lead to heart failure. The identification of molecular mechanisms promoting myocardial regeneration represents a promising strategy to improve cardiac function. Here we show that IGF2BP3 plays an important role in regulating adult cardiomyocyte proliferation and regeneration in a mouse model of myocardial infarction. IGF2BP3 expression progressively decreases during postnatal development and becomes undetectable in the adult heart. However, it becomes upregulated after cardiac injury. Both gain- and loss-of-function analyses indicate that IGF2BP3 regulates cardiomyocyte proliferation in vitro and in vivo. In particular, IGF2BP3 promotes cardiac regeneration and improves cardiac function after myocardial infarction. Mechanistically, we demonstrate that IGF2BP3 binds to and stabilizes MMP3 mRNA through interaction with N6-methyladenosine modification. The expression of MMP3 protein is also progressively downregulated during postnatal development. Functional analyses indicate that MMP3 acts downstream of IGF2BP3 to regulate cardiomyocyte proliferation. These results suggest that IGF2BP3-mediated post-transcriptional regulation of extracellular matrix and tissue remodeling contributes to cardiomyocyte regeneration. They should help to define therapeutic strategy for ameliorating myocardial infarction by inducing cell proliferation and heart repair.

Propofol inhibits myocardial injury induced by microvesicles derived from hypoxia-reoxygenated endothelial cells via lncCCT4-2/CCT4 signaling.

BACKGROUND: Ischemia-reperfusion (IR) induces increased release of extracellular vesicles in the heart and exacerbates myocardial IR injury. We have previously shown that propofol attenuates hypoxia/reoxygenation (HR)-induced injury in human umbilical vein endothelial cells (HUVECs) and that microvesicles derived from propofol-treated HUVECs inhibit oxidative stress in endothelial cells. However, the role of microvesicles derived from propofol post-treated HUVECs ((HR + P)-EMVs) in IR-injured cardiomyocytes is unclear. In this study, we aimed to investigate the role of (HR + P)-EMVs in cardiac IR injury compared to microvesicles derived from hypoxic/reoxygenated HUVECs (HR-EMVs) and to elucidate the underlying mechanisms. METHODS: Hypoxia/reoxygenation (HR) models of HUVECs and AC16 cells and a mouse cardiac IR model were established. Microvesicles from HR-injured HUVECs, DMSO post-treated HUVECs and propofol post-treated HUVECs were extracted by ultra-high speed centrifugation, respectively. The above EMVs were co-cultured with HR-injured AC16 cells or injected intracardially into IR mice. Flow cytometry and immunofluorescence were used to determine the levels of oxidative stress and apoptosis in cardiomyocytes. Apoptosis related proteins were detected by Western blot. Echocardiography for cardiac function and Evans blue-TTC staining for myocardial infarct size. Expression of lncCCT4-2 in EMVs and AC16 cells was analysed by whole transcriptome sequencing of EMVs and RT-qPCR. The molecular mechanism of inhibition of myocardial injury by (HR + P)-EMVs was elucidated by lentiviral knockdown of lncCCT4-2, plasmid overexpression or knockdown of CCT4, and actinomycin D assay. RESULTS: In vitro and in vivo experiments confirmed that HR-EMVs exacerbated oxidative stress and apoptosis in IR-injured cardiomyocytes, leading to increased infarct size and worsened cardiac function. Notably, (HR + P)-EMVs induced significantly less oxidative stress and apoptosis in IR-injured cardiomyocytes compared to HR-EMVs. Mechanistically, RNA sequencing of EMVs and RT-qPCR showed that lncCCT4-2 was significantly upregulated in (HR + P)-EMVs and cardiomyocytes co-cultured with (HR + P)-EMVs. Reduction of lncCCT4-2 in (HR + P)-EMVs enhanced oxidative stress and apoptosis in IR-injured cardiomyocytes. Furthermore, the anti-apoptotic activity of lncCCT4-2 from (HR + P)-EMVs was achieved by increasing the stability of CCT4 mRNA and promoting the expression of CCT4 protein in cardiomyocytes. CONCLUSIONS: Our study showed that (HR + P)-EMVs uptake by IR-injured cardiomyocytes upregulated lncCCT4-2 in cardiomyocytes and promoted CCT4 expression, thereby inhibiting HR-EMVs induced oxidative stress and apoptosis.

Propofol inhibits myocardial injury induced by microvesicles derived from hypoxiareoxygenated endothelial cells via lncCCT4-2/CCT4 signaling

BACKGROUND: Ischemia-reperfusion (IR) induces increased release of extracellular vesicles in the heart and exacerbates myocardial IR injury. We have previously shown that propofol attenuates hypoxia/reoxygenation (HR)-induced injury in human umbilical vein endothelial cells (HUVECs) and that microvesicles derived from propofol-treated HUVECs inhibit oxidative stress in endothelial cells. However, the role of microvesicles derived from propofol post-treated HUVECs ((HR + P)-EMVs) in IR-injured cardiomyocytes is unclear. In this study, we aimed to investigate the role of (HR + P)-EMVs in cardiac IR injury compared to microvesicles derived from hypoxic/reoxygenated HUVECs (HR-EMVs) and to elucidate the underlying mechanisms. METHODS: Hypoxia/reoxygenation (HR) models of HUVECs and AC16 cells and a mouse cardiac IR model were established. Microvesicles from HR-injured HUVECs, DMSO post-treated HUVECs and propofol post-treated HUVECs were extracted by ultra-high speed centrifugation, respectively. The above EMVs were co-cultured with HR-injured AC16 cells or injected intracardially into IR mice. Flow cytometry and immunofluorescence were used to determine the levels of oxidative stress and apoptosis in cardiomyocytes. Apoptosis related proteins were detected by Western blot. Echocardiography for cardiac function and Evans blue-TTC staining for myocardial infarct size. Expression of lncCCT4-2 in EMVs and AC16 cells was analysed by whole transcriptome sequencing of EMVs and RT-qPCR. The molecular mechanism of inhibition of myocardial injury by (HR + P)-EMVs was elucidated by lentiviral knockdown of lncCCT4-2, plasmid overexpression or knockdown of CCT4, and actinomycin D assay. RESULTS: In vitro and in vivo experiments confirmed that HR-EMVs exacerbated oxidative stress and apoptosis in IR-injured cardiomyocytes, leading to increased infarct size and worsened cardiac function. Notably, (HR + P)-EMVs induced significantly less oxidative stress and apoptosis in IR-injured cardiomyocytes compared to HR-EMVs. Mechanistically, RNA sequencing of EMVs and RT-qPCR showed that lncCCT4-2 was significantly upregulated in (HR + P)-EMVs and cardiomyocytes co-cultured with (HR + P)-EMVs. Reduction of lncCCT4-2 in (HR + P)-EMVs enhanced oxidative stress and apoptosis in IR-injured cardiomyocytes. Furthermore, the anti-apoptotic activity of lncCCT4-2 from (HR + P)-EMVs was achieved by increasing the stability of CCT4 mRNA and promoting the expression of CCT4 protein in cardiomyocytes. CONCLUSIONS: Our study showed that (HR + P)-EMVs uptake by IR-injured cardiomyocytes upregulated lncCCT4-2 in cardiomyocytes and promoted CCT4 expression, thereby inhibiting HR-EMVs induced oxidative stress and apoptosis. Highlights Microvesicles from hypoxic/reoxygenated HUVECs (HR-EMVs) exacerbated oxidative stress and apoptosis in IR-injured cardiomyocytes. Microvesicles from propofol post-treated HUVECs ((HR + P)-EMVs) induced diminished oxidative stress and apoptosis in IR-injured cardiomyocytes compared with microvesicles from hypoxic/reoxygenated HUVECs (HR-EMVs). lncCCT4-2 was significantly highly expressed in (HR + P)-EMVs and cardiomyocytes co-cultured with (HR + P)-EMVs, and reduction of lncCCT4-2 in (HR + P)-EMVs enhanced oxidative stress and apoptosis in IR-injured cardiomyocytes. lncCCT4-2 inhibited HR-EMVs induced oxidative stress and apoptosis in HR-injured AC16 cells by increasing the stability of CCT4 mRNA and promoting the expression of CCT4 protein in AC16 cells.

Fucoxanthin Loaded in Palm Stearin- and Cholesterol-Based Solid Lipid Nanoparticle-Microcapsules, with Improved Stability and Bioavailability In Vivo.

Fucoxanthin (FX) is a marine carotenoid that has proven to be a promising marine drug due to the multiple bioactivities it possesses. However, the instability and poor bioavailability of FX greatly limit its application in pharmaceuticals or functional foods. In this study, the creative construction of a solid lipid nanoparticle-microcapsule delivery system using mixed lipids of palm stearin and cholesterol wrapped with gelatin/Arabic gum to load lipophilic FX was fabricated, aiming to improve the stability and bioavailability of FX. The results showed that the encapsulated efficiency (EE) and drug loading capacity (LC) of optimized FX microcapsules (FX-MCs) obtained were as high as 96.24 ± 4.60% and 0.85 ± 0.04%, respectively, after single-factor experiments. The average particle size was 1154 ± 54 nm with negative Zeta potential (-20.71 ± 0.93 mV) as depicted with size-zeta potential spectrometer. The differential scanning calorimeter (DSC) and thermogravimetric analyzer (TG) results indicated that FX-MC has a higher Tg and slower weight loss than FX monomers (FX crystal) and blank MCs. Besides, The Fourier transform infrared spectrometer (FTIR) confirmed the good double encapsulation of FX into the solid lipid and composite coacervate. Moreover, the encapsulated FX showed higher storage stability, sustained release (55.02 ± 2.80% release in 8 h), and significantly improved bioavailability (712.33%) when compared to free FX. The research results can provide a principle theoretical basis for the development and application of FX in pharmaceuticals or functional foods.

Propofol Upregulates MicroRNA-30b to Inhibit Excessive Autophagy and Apoptosis and Attenuates Ischemia/Reperfusion Injury In Vitro and in Patients.

Evidence reveals that propofol protects cells via suppressing excessive autophagy induced by hypoxia/reoxygenation (H/R). Previously, we found in a genome-wide microRNA profile analysis that several autophagy-related microRNAs were significantly altered during the process of H/R in the presence or absence of propofol posthypoxia treatment (P-PostH), but how these microRNAs work in P-PostH is still largely unknown. Here, we found that one of these microRNAs, microRNA-30b (miR-30b), in human umbilical vein endothelial cells (HUVECs) was downregulated by H/R treatment but significantly upregulated by 100 M propofol after H/R treatment. miR-30b showed similar changes in open heart surgery patients. By dual-luciferase assay, we found that Beclin-1 is the direct target of miR-30b. This conclusion was also supported by knockdown or overexpression of miR-30b. Further studies showed that miR-30b inhibited H/R-induced autophagy activation. Overexpression or knockdown of miR-30b regulated autophagy-related protein gene expression in vitro. To clarify the specific role of propofol in the inhibition of autophagy and distinguish the induction of autophagy from the damage of autophagy flux, we used bafilomycin A1. LC3-II levels were decreased in the group treated with propofol combined with bafilomycin A1 compared with the group treated with bafilomycin A1 alone after hypoxia and reoxygenation. Moreover, HUVECs transfected with Ad-mCherry-GFP-LC3b confirmed the inhibitory effect of miR-30b on autophagy flux. Finally, we found that miR-30b is able to increase the cellular viability under the H/R condition, partially mimicking the protective effect of propofol which suppressed autophagy via enhancing miR-30b and targeting Beclin-1. Therefore, we concluded that propofol upregulates miR-30b to repress excessive autophagy via targeting Beclin-1 under H/R condition. Thus, our results revealed a novel mechanism of the protective role of propofol during anesthesia. Clinical Trial Registration Number. This trial is registered with ChiCTR-IPR-14005470. The name of the trial register: Propofol Upregulates MicroRNA-30b to Repress Beclin-1 and Inhibits Excessive Autophagy and Apoptosis.

Comparative Genome Analysis Reveals Phylogenetic Identity of Bacillus velezensis HNA3 and Genomic Insights into Its Plant Growth Promotion and Biocontrol Effects.

Bacillus velezensis HNA3, a potential plant growth promoter and biocontrol rhizobacterium, was isolated from plant rhizosphere soils in our previous work. Here, we sequenced the entire genome of the HNA3 strain and performed a comparative genome analysis. We found that HNA3 has a 3,929-kb chromosome with 46.5% GC content and 4,080 CDSs. We reclassified HNA3 as a Bacillus velezensis strain by core genome analysis between HNA3 and 74 previously defined Bacillus strains in the evolutionary tree. A comparative genomic analysis among Bacillus velezensis HNA3, Bacillus velezensis FZB42, Bacillus amyloliquefaciens DSM7, and Bacillus subtilis 168 showed that only HNA3 has one predicated secretory protein feruloyl esterase that catalyzes the hydrolysis of plant cell wall polysaccharides. The analysis of gene clusters revealed that whole biosynthetic gene clusters type Lanthipeptide was exclusively identified in HNA3 and might lead to the synthesis of new bioactive compounds. Twelve gene clusters were detected in HNA3 responsible for the synthesis of 14 secondary metabolites including Bacillaene, Fengycin, Bacillomycin D, Surfactin, Plipastatin, Mycosubtilin, Paenilarvins, Macrolactin, Difficidin, Amylocyclicin, Bacilysin, Iturin, Bacillibactin, Paenibactin, and others. HNA3 has 77 genes encoding for possible antifungal and antibacterial secreting carbohydrate active enzymes. It also contains genes involved in plant growth promotion, such as 11 putative indole acetic acid (IAA)-producing genes, spermidine and polyamine synthase genes, volatile compound producing genes, and multiple biofilm related genes. HNA3 also has 19 phosphatase genes involved in phosphorus solubilization. Our results provide insights into the genetic characteristics responsible for the bioactivities and potential application of HNA3 as plant growth-promoting strain in ecological agriculture. IMPORTANCE This study is the primary initiative to identify Bacillus velezensis HNA3 whole genome sequence and reveal its genomic properties as an effective biocontrol agent against plant pathogens and a plant growth stimulator. HNA3 genetic profile can be used as a reference for future studies that can be applied as a highly effective biofertilizer and biofungicide inoculum to improve agriculture productivity. HNA3 reclassified in the phylogenetic tree which may be helpful for highly effective strain engineering and taxonomy. The genetic comparison among HNA3 and closely similar species B. velezensis FZB42, B. amyloliquefaciens DSM7, and B. subtilis 168 demonstrates some distinctive genetic properties of HNA3 and provides a basis for the genetic diversity of the Bacillus genus, which allows developing more effective eco-friendly resources for agriculture and separation of Bacillus velezensis as distinct species in the phylogenetic tree.

Propofol-induced MiR-20b expression initiates endogenous cellular signal changes mitigating hypoxia/re-oxygenation-induced endothelial autophagy in vitro.

Certain miRNAs can attenuate hypoxia/re-oxygenation-induced autophagic cell death reported in our previous studies, but how these miRNAs regulate the autophagy-related cellular signaling pathway in preventing cell death is largely unknown. In the current study, the autophagy-related miRNAs of hsa-miR-20b were investigated in an in vitro model of hypoxia/re-oxygenation-induced endothelial autophagic cell death. Of these, miR-20b was found to be the most important miRNA which targeted on the key autophagy kinase ULK1 and inhibited hypoxia/re-oxygenation injury-induced autophagy by decreasing both autophagosomes and LC3I to II transition rate and P62 degradation. These processes were reversed by the transfection of an miR-20b inhibitor. Re-expression of ULK1 restores miR-20b-inhibited autophagy. Propofol, a commonly used anesthetic, promoted miR-20b and METTL3 expression and attenuated endothelial autophagic cell death. The inhibited endogenous expression of miR-20b or silenced METTL3 diminished the protective effect of propofol and accentuated autophagy. Additionally, METTL3 knockdown significantly inhibited miR-20b expression but up-regulated pri-miR-20b expression. Together, our data shows that propofol protects against endothelial autophagic cell death induced by hypoxia/re-oxygenation injury, associated with activation of METTL3/miR-20b/ULK1 cellular signaling.

miR-132-3p priming enhances the effects of mesenchymal stromal cell-derived exosomes on ameliorating brain ischemic injury.

BACKGROUNDS/AIMS: Mesenchymal stromal cell-derived exosomes (MSC-EXs) could exert protective effects on recipient cells by transferring the contained microRNAs (miRs), and miR-132-3p is one of angiogenic miRs. However, whether the combination of MSC-EXs and miR-132-3p has better effects in ischemic cerebrovascular disease remains unknown. METHODS: Mouse MSCs transfected with scrambler control or miR-132-3p mimics were used to generate MSC-EXs and miR-132-3p-overexpressed MSC-EXs (MSC-EXsmiR-132-3p). The effects of EXs on hypoxia/reoxygenation (H/R)-injured ECs in ROS generation, apoptosis, and barrier function were analyzed. The levels of RASA1, Ras, phosphorylations of PI3K, Akt and endothelial nitric oxide synthesis (eNOS), and tight junction proteins (Claudin-5 and ZO-1) were measured. Ras and PI3K inhibitors were used for pathway analysis. In transient middle cerebral artery occlusion (tMCAO) mouse model, the effects of MSC-EXs on the cerebral vascular ROS production and apoptosis, cerebral vascular density (cMVD), Evans blue extravasation, brain water content, neurological deficit score (NDS), and infarct volume were determined. RESULTS: MSC-EXs could deliver their carried miR-132-3p into target ECs, which functionally downregulated the target protein RASA1, while upregulated the expression of Ras and the downstream PI3K phosphorylation. Compared to MSC-EXs, MSC-EXsmiR-132-3p were more effective in decreasing ROS production, apoptosis, and tight junction disruption in H/R-injured ECs. These effects were associated with increased levels of phosphorylated Akt and eNOS, which could be abolished by PI3K inhibitor (LY294002) or Ras inhibitor (NSC 23766). In the tMCAO mouse model, the infusion of MSC-EXsmiR-132-3p was more effective than MSC-EXs in reducing cerebral vascular ROS production, BBB dysfunction, and brain injury. CONCLUSION: Our results suggest that miR-132-3p promotes the beneficial effects of MSC-EXs on brain ischemic injury through protecting cerebral EC functions.

Heart­lung crosstalk in pulmonary arterial hypertension following myocardial infarction (Review).

Left heart disease is the main cause of clinical pulmonary arterial hypertension (PAH). Common types of left heart disease that result in PAH include heart failure, left ventricular systolic dysfunction, left ventricular diastolic dysfunction and valvular disease. It is currently believed that mechanical pressure caused by high pulmonary venous pressure is the main cause of myocardial infarction (MI) in individuals with ischemic cardiomyopathy and left ventricular systolic dysfunction. In the presence of decreased cardiac function, vascular remodeling of pulmonary vessels in response to long­term stimulation by high pressure in turn leads to exacerbation of PAH. However, the underlying pathological mechanisms remain unclear. Elucidating the association between the development of MI and PAH may lead to a better understanding of potential risk factors and better disease treatment. In this article, the pathophysiological effects of multiple systems in individuals with MI and PAH were reviewed in order to provide a general perspective on various potential interactions between cardiomyocytes and pulmonary vascular cells.

Protective effect of propofol on ischemia-reperfusion injury detected by HPLC-MS/MS targeted metabolic profiling.

Ischemia-reperfusion injury(IRI), described as tissue damage caused by reversible ischemic injury or hypoxia prior to the blood supply restoration, is a common pathological phenomenon. In recent study, a hypoxia-reoxygenation (H/R) in the presence or absence of propofol posthypoxia treatment (P-PostH) cell model was built to simulate the condition of IRI, and researchers found propofol may protect cells by suppressing autophagic cell death. To investigate the mechanism underling the protective effect of propofol. A metabolomic analysis was performed in this study using ultra performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF- MS) to compare the metabolism during the process of H/R in the presence or absence of P-PostH. A total of 22 metabolites were detected varied after propofol posthypoxia treatment. Pathway analysis revealed these metabolites were mainly involved in the purine metabolic pathway, three carboxylic acid metabolic pathways, alanine, aspartate and glutamate metabolism pathway and lipid metabolism pathway. We measured the level of Hypoxanthine to verify the metabolomics work, for pathway analysis, we detect the level of reactive oxygen species with H/R and P-PostH treatment. Our study achieved a global comparison of metabolism profiling of H/R cell model with or without propofol posthypoxic treatment. The result indicated that propofol can attenuate endothelial injury caused by IRI by reducing oxidative damage.

Inhibition of Caveolae Contributes to Propofol Preconditioning-Suppressed Microvesicles Release and Cell Injury by Hypoxia-Reoxygenation.

Endothelial microvesicles (EMVs), released after endothelial cell (EC) apoptosis or activation, may carry many adverse signals and propagate injury by intercellular transmission. Caveolae are 50-100 nm cell surface plasma membrane invaginations involved in many pathophysiological processes. Recent evidence has indicated EMVs and caveolae may have functional effects in cells undergoing H/R injury. Propofol, a widely used anaesthetic, confers antioxidative stress capability in the same process. But the connection between EMVs, H/R, and caveolae remains largely unclear. Here, we found that H/R significantly increased the release of EMVs, the expression of CAV-1 (the structural protein responsible for maintaining the shape of caveolae), oxidative stress, and the mitochondrial damage, and all these changes were inhibited by propofol preconditioning. Interestingly, the caveolae inhibitor Mß-CD strengthened the protective effect of propofol preconditioning. We further found that the release of EMVs is more significantly reduced under propofol preconditioning in the presence of the caveolae inhibitor Mß-CD. EMVs released from H/R-treated cells caused a substantially increased mitochondrial and cellular damage to normal HUVECs after 4 hours of coculture. Thus, we conclude that inhibition of caveolae contributes to propofol preconditioning-suppressed microvesicles release and cell injury by H/R.

Propofol Through Upregulating Caveolin-3 Attenuates Post-Hypoxic Mitochondrial Damage and Cell Death in H9C2 Cardiomyocytes During Hyperglycemia.

BACKGROUND/AIMS: Hearts from diabetic subjects are susceptible to myocardial ischemia reperfusion (I/R) injury. Propofol has been shown to protect against myocardial I/R injury due to its antioxidant properties while the underlying mechanism remained incompletely understood. Thus, this study aimed to determine whether or not propofol could attenuate myocardial I/R injury by attenuating mitochondrial dysfunction/damage through upregulating Caveolin (Cav)-3 under hyperglycemia. METHODS: Cultured rat cardiomyocyte H9C2 cells were subjected to hypoxia/reoxygenation (H/R) in the absence or presence of propofol under high glucose (HG), and cell viability, lactate dehydrogenase (LDH) and mitochondrial viability as well as creatine kinase-MB (CK-MB), cardiac troponin I (cTnI) and intracellular adenosine triphosphate (ATP) content were measured with colorimetric Enzyme-Linked Immunosorbent Assays. Intracellular levels of oxidative stress was assessed using 2,7-dichlorodihydrofluorescein diacetate (DCF-DA) fluorescent staining and mitochondrial-dependent apoptosis was assessed by detecting mitochondrial membrane potential and the activation of apoptotic caspases 3 and 9. RESULTS: Exposure of cells to HG without or with H/R both significantly increased cell injury, cell apoptosis and enhanced oxidative stress that were associated with mitochondrial dysfunction and decreased Cav-3 protein expression. All these changes were further exacerbated following H/R under HG. Administration of propofol at concentrations from 12.5 to 50 µM but not 100 µM significantly attenuated H/R injury that was associated with increased Cav-3 expression and activation of the prosurvival proteins Akt and STAT3 with the optimal protective effects seen at 50 µM of propofol (P25). The beneficial effects of propofol(P25) were abrogated by Cav-3 disruption with ß-methyl-cyclodextrin. CONCLUSION: Propofol counteracts cardiomyocyte H/R injury by attenuating mitochondrial damage and improving mitochondrial biogenesis through upregulating Cav-3 during hyperglycemia.

Differential microRNA profiling in a cellular hypoxia reoxygenation model upon posthypoxic propofol treatment reveals alterations in autophagy signaling network.

Recent studies indicate that propofol may protect cells via suppressing autophagic cell death caused by excessive reactive oxygen species induced by hypoxia reoxygenation (H/R). It is established that gene expression patterns including autophagy-related genes changed significantly during the process of H/R in the presence or absence of propofol posthypoxia treatment (P-PostH). The reasons for such differences, however, remain largely unknown. MicroRNAs provide a novel mechanism for gene regulation. In the present study, we systematically analyzed the alterations in microRNA expression using human umbilical vein endothelial cells (HUVECs) subjected to H/R in the presence or absence of posthypoxic propofol treatment. Genome-wide profiling of microRNAs was then conducted using microRNA microarray. Fourteen miRNAs are differentially expressed and six of them were validated by the quantitative real-time PCR (Q-PCR) of which three were substantially increased, whereas one was decreased. To gain an unbiased global perspective on subsequent regulation by altered miRNAs, predicted targets of ten miRNAs were analyzed using the Gene Ontology (GO) analysis to build signaling networks. Interestingly, six of the identified microRNAs are known to target autophagy-related genes. In conclusion, our results revealed that different miRNA expression patterns are induced by propofol posthypoxia treatment in H/R and the alterations in miRNA expression patterns are implicated in regulating distinctive autophagy-related gene expression.