Alginate oligosaccharides exert protective effects on hydrogen peroxide-induced senescence in H9C2 cardiomyocytes by regulating the redox state of cells.

Aging is a known independent risk factor for several cardiovascular diseases. Here, we evaluated potential effects and possible mechanisms through which alginate oligosaccharides (AOS) affect hydrogen peroxide (H2O2)-induced senescence in H9C2 cardiomyocytes. A series of AOS molecules, including oligoM, oligoG, M-5, and G-5, were investigated. AOS significantly decreased SA-ß-gal and DAPI-stained positive cells, downregulated p53 and p21 (aging-related markers) expression, and eventually protected H9C2 cells from H2O2-induced senescence. AOS decreased reactive oxygen species and malondialdehyde production, recovered mitochondrial function, and alleviated the oxidative stress state by regulating PGC-1α and NADPH oxidase subunit expression. Furthermore, AOS treatment restored the expression of antioxidant enzymes in senescent H9C2 cells. Thus, our results show in vitro evidence that AOS alleviate senescence in H9C2 cells by regulating the redox state; thus, AOS may be an effective therapeutic agent that could protect against cardiomyocyte senescence.

REDUCED CX43 EXPRESSION INDUCES AUTOPHAGY THROUGH ACTIVATION OF THE AMPK-MTOR-ULK1 SIGNALING PATHWAY IN THE COMMON BILE DUCT LIGATION RAT HEART.

ABSTRACT: Backgrounds: This study aimed to investigate the relationship between Cx43 expression and autophagy mediated by the AMPK-mTOR-Ulk1 signaling pathway in jaundice heart. Methods: In this study, a jaundice model was established in common bile duct ligation (CBDL) rats. Cardiac injury was assessed using various methods including myocardial injury indicators, echocardiography, transmission electron microscopy, hematoxylin and eosin staining, Masson staining, immunohistochemical analyses, and immunofluorescence staining. We investigated the regulatory relationship between Cx43, autophagy, and the AMPK-mTOR-ULK pathway in vivo by administering autophagy agonists (Rapa), autophagy inhibitors (3-MA), and Cx43 inhibitors (Gap 26). In vitro , we observed the relationship between autophagy and the AMPK-mTOR-ULK1 pathway in cells by exposing them to the AMPK inhibitor Compound C and the AMPK activator AICAR. Results: We found that CBDL induced autophagy through the AMPK-mTOR-ULK pathway, leading to the inhibition of myocardial dysfunction. Rapamycin pretreatment with CBDL3d exhibited a protective effect against myocardial injury and promoted autophagy. In contrast, 3-MA had no impact. Pretreatment with rapamycin at CBDL2w enhanced autophagy and aggravated cardiac injury; however, inhibition of autophagy using 3-MA attenuated cardiac injury. Cell viability was enhanced by AMPK inhibitors and inhibited by AMPK agonists. In addition, we observed that increased autophagy led to decreased Cx43 expression, which negatively affected cardiac function. Conclusions: CBDL induces myocardial injury in rats and activates autophagy through the AMPK-mTOR-ULK pathway, resulting in decreased Cx43 protein levels. A moderate increase in early autophagy in CBDL can improve cardiac injury, while late inhibition of autophagy can reduce myocardial injury.

HYPERBILIRUBINEMIA AGGRAVATES RENAL ISCHEMIA REPERFUSION INJURY BY EXACERBATING PINK1-PARKIN-MEDIATED MITOPHAGY.

ABSTRACT: Background: Hyperbilirubinemia is a common perioperative complication, which is associated with acute kidney injury. Bilirubin permeabilizes mitochondrial membranes leading to mitochondrial swelling and dysfunction. In this study, we aimed to determine the association between PINK1-PARKIN-mediated mitophagy and renal ischemia-reperfusion (IR) injury aggravated by hyperbilirubinemia. Methods: A C57BL/6 mouse hyperbilirubinemia model was induced via intraperitoneal injection of bilirubin solution. In addition, a hypoxia/reoxygenation (H/R) injury model of TCMK-1 cells was established. In these models, we determined the effects of hyperbilirubinemia on oxidative stress, apoptosis, mitochondrial damage, and fibrosis. Results:In vitro , colocalization of GFP-LC3 puncta and Mito-Tracker Red showed that the number of mitophagosomes increased in TCMK-1 cells under H/R and bilirubin condition. Silencing of PINK1 or inhibition of autophagy alleviated mitochondrial damage, oxidative stress, and apoptosis in H/R injury aggravated by bilirubin and decreased cell death detected by methyl-thiazolyl-tetrazolium. In vivo , hyperbilirubinemia increased serum creatinine level in the renal IR injury mice model. Hyperbilirubinemia enhanced apoptosis induced by renal IR. In addition, hyperbilirubinemia increased mitophagosomes and autophagosomes and disrupted mitochondrial cristae in the IR kidney. Inhibition of PINK1 or autophagy reduced histological damages by alleviating apoptosis in renal IR injury, aggravated by hyperbilirubinemia. 3-MA or PINK1-shRNA-AAV9 treatment decreased the area of collagen and proteins related to fibrosis in renal IR injury, aggravated by hyperbilirubinemia. Conclusions: We have demonstrated that hyperbilirubinemia aggravated oxidative stress, apoptosis, mitochondrial damage, and fibrosis in renal IR injury by exacerbating PINK1-PARKIN-mediated mitophagy.

Impact of hyperbilirubinemia associated acute kidney injury on chronic kidney disease after aortic arch surgery: a retrospective study with follow-up of 1-year.

BACKGROUND: Hyperbilirubinemia (HB) is a serious complication in aortic arch surgery, which is associated with acute kidney injury (AKI). The association between HB and chronic kidney disease (CKD) is unknown. The aim of this study was to investigate the impact of HB associated AKI on CKD after aortic arch surgery. METHODS: We reviewed 284 patients who underwent aortic arch surgery from 2016 to 2020 in our hospital. AKI was defined as a 50% increase in sCr from baseline value within the first 7 postoperative days. HB was defined as total bilirubin > 51.3 µmol/L. Patients were divided into 3 groups based on AKI and HB: HB associated AKI (HB-AKI) group (AKI patients suffered HB within the first 7 postoperative days); AKI without HB group and Non-AKI group. RESULTS: Follow-up for 204 patients ranged from 3 to 12 months. Kaplan-Meier analysis showed that the 1-year cumulative incidence of CKD was highest in HB-AKI (32.6%) than AKI without HB (17.8%) and Non-AKI (7.4%, log-rank test, p < 0.001), and the incidence of CKD was higher in HB group than that in Non-HB group (26.7% vs. 13.9%, log-rank test, p = 0.015). Preoperative sCr (HR 1.010, 95% CI 1.004-1.016, p = 0.001), AKI without HB (HR 2.887, 95% CI 1.133-7.354, p = 0.026) and HB-AKI (HR 4.490, 95% CI 1.59-12.933, p = 0.005) were associated with CKD during 1-year follow-up. CONCLUSIONS: Patients suffering HB associated AKI were at more increased odds of CKD than patients suffering AKI without HB after aortic arch surgery.

Association of intraoperative hypotension with acute kidney injury after liver resection surgery: an observational cohort study.

BACKGROUND: Acute kidney injury (AKI) is a major complication following liver resection. The aim of this study was to determine the risk factors for AKI after hepatic resection and whether intraoperative hypotension (IOH) was related to AKI. METHODS: Adult patients (≥ 18 years) undergoing liver resection between November 2017 and November 2019 at our hospital were retrospectively reviewed. AKI was defined as ≥50% increase in serum creatinine from baseline value within 48 h after surgery. IOH was defined as the lowest absolute mean arterial pressure (MAP) < 65 mmHg for more than 10 cumulative minutes during the surgery. Patients were divided into AKI group and non-AKI group, and were stratified by age ≥ 65 years. RESULTS: 796 patients who met our inclusion and exclusion criteria were analyzed. After multivariable regression analysis, the IOH (OR, 2.565; P = 0.009) and age ≥ 65 years (OR, 2.463; P = 0.008) were risk factors for AKI. The IOH (OR, 3.547; P = 0.012) and received red blood cell (OR, 3.032; P = 0.036) were risk factors of AKI in age ≥ 65 years patients. CONCLUSIONS: The IOH and age ≥ 65 years were risk factors for postoperative AKI, and IOH was associated with AKI in age ≥ 65 years patients following liver resection.

Hyperbilirubinemia Induces Pro-Apoptotic Effects and Aggravates Renal Ischemia Reperfusion Injury.

AIMS: Hyperbilirubinemia is associated with postoperative acute kidney injury in patients undergoing cardiac surgeries. A high concentration of bilirubin could induce oxidative stress and cell apoptosis. The aim of this study was to investigate whether hyperbilirubinemia aggravated the renal tubule cells injury and the pro-apoptotic potential of bilirubin on renal ischemia reperfusion injury (RIRI). METHODS: The human proximal tubular epithelial cell line HK-2 cells were challenged with a gradient concentration of bilirubin for 24 h. Cell injury was assessed by flow cytometry and MTT assay. Bilirubin was injected intraperitoneally into male Sprague-Dawley rats once every 12 h (100 mg/kg), 3 times in total. The same solvent volume without bilirubin powder was used as vehicle in non-bilirubin injection groups. The RIRI surgical procedure was a bilateral renal pedicles clamping (45 min) followed by 30 h reperfusion. The rats were divided into 4 groups: negative control (NC), similar surgical procedures without clamping; Bil, bilirubin injection for 36 h, then rats were sacrificed; RIRI, RIRI surgical procedures; Bil + RIRI, RIRI applied 6 h later than the first bilirubin injection, rats were sacrificed after another 30 h. RESULTS: In vitro, bilirubin induced cell apoptosis and significantly decreased the cell viability of HK-2 cells. Bilirubin induced the active caspase 3 and phosphorylation of p38 in HK-2 cells. In vivo, serum creatinine was higher in Bil + RIRI compared with RIRI (p < 0.01). The tubular injury scores of hematoxylin and eosin and tubular necrosis scores of periodic acid-Schiff were higher in Bil + RIRI than these in RIRI (All p < 0.05). The number of Tunel-positive nuclei was higher in Bil + RIRI compared to RIRI (p < 0.001). The active caspase 3 and phosphorylation of p38 were higher and the Bcl2 was lower in Bil + RIRI compared to RIRI. Moreover, the apoptosis level was higher in Bil compared to NC. CONCLUSIONS: Our results reveal that the hyperbilirubinemia induces pro-apoptotic effects and aggravates RIRI.

Correlation between Histone Deacetylase 9 and Regulatory T Cell in Patients with Chronic Heart Failure.

Heart failure (HF) is the end stage of various kinds of cardiovascular diseases and leads to a high mortality worldwide. Numerous studies have demonstrated that frequencies of CD4+CD25+Foxp3+ regulatory T cells (Tregs) are reduced in HF patients and properly expanding Tregs attenuates HF progression. Histone deacetylase (HDAC) 9 has been revealed to contribute to several cardiovascular and cerebrovascular diseases. Plenty of studies showed that HDAC9 negatively regulated the number and function of Tregs. Thus, we aim to investigate the expression of HDAC 9 in patients with chronic heart failure (CHF) and the relationship among HDAC9, Tregs and CHF. Our research showed a reduced number of Tregs and an increased expression of HDAC9 mRNA in CHF patients. Patients with CHF were divided into two groups by heart function grade of New York Heart Association (NYHA), we found that the HDAC9 mRNA expression level in NYHA grade II-III group were lower than that in NYHA grade IV group. More importantly, the correlation study suggested that the expression of HDAC9 mRNA was negatively correlated to Tregs frequency and left ventricular ejection fraction (LVEF), whereas positively correlated to larger left ventricular end-diastolic dimension (LVEDD) and B-type natriuretic peptide (BNP) in patients with CHF. The correlation studies also showed a positive correlation between HDAC9 and the severity of CHF. Our research suggests that HDAC9 may be a new indicator for assessing CHF and it may offer a new direction for research of CHF.

Highly Efficient Interception and Precipitation of Uranium(VI) from Aqueous Solution by Iron-Electrocoagulation Combined with Cooperative Chelation by Organic Ligands.

A new strategy combining iron-electrocoagulation and organic ligands (OGLs) cooperative chelation was proposed to screen and precipitate low concentrations (0-18.52 µmol/L) of uranium contaminant in aqueous solution. We hypothesized that OGLs with amino, hydroxyl, and carboxyl groups hydrophobically/hydrophilically would realize precuring of uranyl ion at pH < 3.0, and the following iron-electrocoagulation would achieve faster and more efficient uranium precipitation. Experimentally, the strategy demonstrated highly efficient uranium(VI) precipitation efficiency, especially with hydrophilic macromolecular OGLs. The uranium removal efficiency at optimized experimental condition reached 99.65%. The decrease of zeta potential and the lattice enwrapping between U-OGLs chelates and flocculation precursor were ascribed to the enhanced uranium precipitation activity. Uranium was precipitated as oxides of U(VI) or higher valences that were easily captured in aggregated micelles under low operation current potential. The actual uranium tailing wastewater was treated, and a satisfied uranium removal efficiency of 99.02% was discovered. After elution of the precipitated flocs, a concentrated uranium solution (up to 106.52 µmol/L) with very few other metallic impurities was obtained. Therefore, the proposed strategy could remove uranium and concentrate it concurrently. This work could provide new insights into the purification and recovery of uranium from aqueous solutions in a cost-effective and environmentally friendly process.

Baicalin Attenuates Cardiac Dysfunction and Myocardial Remodeling in a Chronic Pressure-Overload Mice Model.

BACKGROUND/AIMS: Baicalin has been shown to be effective for various animal models of cardiovascular diseases, such as pulmonary hypertension, atherosclerosis and myocardial ischaemic injury. However, whether baicalin plays a role in cardiac hypertrophy remains unknown. Here we investigated the protective effects of baicalin on cardiac hypertrophy induced by pressure overload and explored the potential mechanisms involved. METHODS: C57BL/6J-mice were treated with baicalin or vehicle following transverse aortic constriction or Sham surgery for up to 8 weeks, and at different time points, cardiac function and heart size measurement and histological and biochemical examination were performed. RESULTS: Mice under pressure overload exhibited cardiac dysfunction, high mortality, myocardial hypertrophy, increased apoptosis and fibrosis markers, and suppressed cardiac expression of PPARα and PPARß/δ. However, oral administration of baicalin improved cardiac dysfunction, decreased mortality, and attenuated histological and biochemical changes described above. These protective effects of baicalin were associated with reduced heart and cardiomyocyte size, lower fetal genes expression, attenuated cardiac fibrosis, lower expression of profibrotic markers, and decreased apoptosis signals in heart tissue. Moreover, we found that baicalin induced PPARα and PPARß/δ expression in vivo and in vitro. Subsequent experiments demonstrated that long-term baicalin treatment presented no obvious cardiac lipotoxicity. CONCLUSIONS: The present results demonstrated that baicalin attenuates pressure overload induced cardiac dysfunction and ventricular remodeling, which would be due to suppressed cardiac hypertrophy, fibrosis, apoptosis and metabolic abnormality.

Baicalin and geniposide inhibit the development of atherosclerosis by increasing Wnt1 and inhibiting dickkopf-related protein-1 expression.

BACKGROUND: Our previous study showed that the combined Chinese herbs containing scutellaria baicalensis georgi and gardenia jasminoids ellis inhibited atherosclerosis. In this study, we sought to determine if baicalin and geniposide could inhibit atherosclerosis through Wnt1 and dickkopf-related protein-1 (DKK1). METHODS: The wild-type and ApoE-/- mice were treated with baicalin, geniposide, and baicalin plus geniposide daily by gavage for 12 weeks. Blood lipid levels were measured with an automatic biochemistry analyzer. Aortic atherosclerotic lesion areas were analyzed with Image-ProPlus software. The mRNA and protein expression of DKK1, Wnt1 and nuclear factor-κB (NF-κB) were measured with RT-PCR and Western Blot. Serum levels of interleukin-12 (IL-12) were quantified with ELISA. RESULTS: The baicalin or geniposide monotherapy as well as combination therapy inhibited the development of atherosclerotic lesions, increased Wnt1 and decreased DKK1 expression and elevated the ratio of Wnt1/DKK1 compared with high-lipid diet group. However, only baicalin or geniposide monotherapy decreased NF-κB expression. Moreover, baicalin and geniposide mono- or combination therapy lowered IL-12 levels. Geniposide reduced both serum total cholesterol and low density lipoprotein levels, while baicalin either alone or in combination with geniposide did not affect serum lipid levels. In human, umbilical vein endothelial cells stimulated by oxidized low density lipoprotein, baicalin and geniposide also increased Wnt1 and decreased DKK1 expression and elevated the ratio of Wnt1/DKK1. CONCLUSIONS: Baicalin and geniposide exert inflammation-regulatory effects and may prevent atherosclerotic lesions through enhancing Wnt1 and inhibiting DKK1 expression.

High-mobility group box-1 protein induces osteogenic phenotype changes in aortic valve interstitial cells.

OBJECTIVES: Calcific aortic valve (AV) disease is known to be an inflammation-related process. High-mobility group box-1 (HMGB1) protein and Toll-like receptor 4 (TLR4) have been reported to participate in several inflammatory diseases. The purpose of the present study was to determine whether the HMGB1-TLR4 axis is involved in calcific AV disease, and to evaluate the effect of HMGB1, and its potential mechanisms, on the pro-osteogenic phenotype change of valvular interstitial cells (VICs). METHODS: Expression of HMGB1 and TLR4 in human calcific AVs was evaluated using immunohistochemical staining and immunoblotting. Cultured VICs were used as an in vitro model. The VICs were stimulated with HMGB1 for analysis, with versus without TLR4 small interfering ribonucleic acid (siRNA), c-Jun N-terminal kinase mitogen-activated protein kinase (JNK MAPK), and nuclear factor kappa-B (NF-κB) inhibitors. RESULTS: Enhanced accumulation of HMGB1 and TLR4 was observed in calcific valves. Moreover, we found that HMGB1 induced high levels of pro-inflammatory cytokine production and promoted the osteoblastic differentiation and calcification of VICs. In addition, HMGB1 induced phosphorylation of JNK MAPK and NF-κB. However, these effects were markedly suppressed by siRNA silencing of TLR4. In addition, blockade of JNK MAPK and NF-κB phosphorylation prohibited HMGB1-induced production of pro-osteogenic factors, and mineralization of VICs. CONCLUSIONS: The HMGB1 protein may promote osteoblastic differentiation and calcification of VICs, through the TLR4-JNK-NF-κB signaling pathway.

Phaeodactylibacter luteus sp. nov., isolated from the oleaginous microalga Picochlorum sp.

A Gram-staining-negative, orange-pigmented, non-motile, aerobic bacterial strain, designated GYP20T, was isolated from a culture of the alga Picochlorum sp., a promising feedstock for biodiesel production, which was isolated from the India Ocean. Growth was observed at temperatures from 20 to 37 °C, salinities from 0 to 3% and pH from 5 to 9.Mg2+ and Ca2+ ions were required for growth. Phylogenetic analysis based on 16S rRNA gene sequencing revealed that the strain was a member of the genus Phaeodactylibacter, which belongs to the family Saprospiraceae. Strain GYP20T was most closely related to Phaeodactylibacter xiamenensis KD52T (95.5% sequence similarity). The major fatty acids were iso-C15 : 1 G, iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3. The predominant respiratory quinone was menaquinone-7 (MK-7). The polar lipids of strain GYP20T were found to consist of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, four unidentified glycolipids, two unidentified phospholipids and three unidentified aminolipids. According to its morphology, physiology, fatty acid composition and 16S rRNA sequence data, the novel strain most appropriately belongs to the genus Phaeodactylibacter, but can readily be distinguished from Phaeodactylibacter xiamenensis GYP20T. The name Phaeodactylibacter luteus sp. nov. is proposed with the type strain GYP20T ( = MCCC 1F01222T = KCTC 42180T).

Baicalin inhibits the expression of monocyte chemoattractant protein-1 and interleukin-6 in the kidneys of apolipoprotein E-knockout mice fed a high cholesterol diet.

Hyperlipidemia is considered an independent risk factor for renal dysfunction and induces a significant increase in the expression of inflammatory mediators, which can be used to evaluate the degree of renal injury. Baicalin is widely used in traditional Chinese herbal medicine and has multiple pharmacological effects. The present study investigated whether baicalin can attenuate the expression of vascular cell adhesion molecule 1 (VCAM­1) via a reduction in the expression of monocyte chemoattractant protein­1 (MCP­1) and interleukin­6 (IL­6) in the kidney of apolipoprotein E (ApoE)­knockout (KO) mice fed a high cholesterol diet. These mice were used as a model of atherosclerosis and were treated with baicalin (100 mg/kg/day) daily by gavage for a period of 12 weeks. By contrast, wild­type male C57BL/6J mice were fed a standard diet. Blood samples were obtained from the angular veins of the mice to measure the total cholesterol (TC) and the expression levels of VCAM­1, MCP­1 and IL­6 in the kidney tissues of the mice were analyzed using reverse transcription quantitative polymerase chain reaction and western blot analysis. Following oral administration of baicalin, no significant difference was observed in the TC in the baicalin group compared with the high cholesterol diet control group. The TC was significantly higher in the AopE­KO mice compared with the wild­type male C57BL/6J mice. The expression levels of VCAM­1, MCP­1 and IL­6 in the kidney tissues of the baicalin group were lower compared with those in the high cholesterol diet control group. The results suggested that baicalin decreased the expression levels of pro­inflammatory mediators and prevented kidney dysfunction in the ApoE­KO mice fed a high cholesterol diet.

Baicalin and geniposide attenuate atherosclerosis involving lipids regulation and immunoregulation in ApoE-/- mice.

Baicalin and geniposide, which are respectively isolated from Scutellariae radix and Gardenia jasminoides, have been known to exhibit a number of pharmacological effects, including anti-inflammatory and anti-oxidant. Here, we primarily aimed to observe the protective effects of these two Chinese herbs on inhibiting the development of atherosclerosis in apolipoprotein E knockout mice via lipids regulation and immunoregulation. After the ApoE-/- mice with high-cholesterol diet had received 12-weeks׳ oral administration of either baicalin or geniposide (100 mg/kg), atherosclerotic plaque areas in aorta were measured and exhibited a prominent decrease in the treated mice. We then assayed serum lipids levels, serum Treg-cell-associated cytokines (TGF-ß1 and IL-10) and the frequency of splenic Treg cells. We found that geniposide notably decreased serum TC and LDL-c. Both baicalin and geniposide treated mice showed much more splenic Treg cells and the correlated cytokines (TGF-ß1 and IL-10). Foxp3, as the marker of Treg cell, was detected in atherosclerotic lesions, and we found that Foxp3 expression at both mRNA and protein levels was up-regulated in addition to increased Foxp3 positive Treg cells detected by immunohistochemistry in baicalin or geniposide treated mice. In conclusion, baicalin and geniposide up-regulated the expression of foxp3, promoted the number and function of Treg cells and ameliorated the atherosclerotic lesions progression partly through lipids regulation and immunoregulation.

Oral administration of baicalin and geniposide induces regression of atherosclerosis via inhibiting dendritic cells in ApoE-knockout mice.

Atherosclerosis is a systemic inflammatory disease characterized by the accumulation of dendritic cells (DCs) and other types of immune cells in atherosclerotic plaque. In this study, baicalin and geniposide were isolated from Scutellaria baicalensis Georgi and Gardenia jasminoids Ellis, which are the plants used in traditional Chinese medicine to treat a variety of inflammatory diseases. We then investigated whether baicalin and geniposide could induce regression of atherosclerotic lesions in ApoE-/- mice fed a high cholesterol diet and used as a model of atherosclerosis. Following model induction, these mice were treated with baicalin (100mg/kg), geniposide (100mg/kg), and then a mixture containing baicalin (100mg/kg) and geniposide (100mg/kg) administered daily by gavage for a period of 12weeks. The combined administration of baicalin and geniposide significantly reduced atherosclerotic lesions, and modulated the phenotype of dendritic cells in bone marrow and atherosclerotic plaque. Geniposide lowered both plasma lipid levels and DC numbers, while baicalin administered either alone or in combination with geniposide did not decrease plasma lipids. Our results suggest that baicalin and geniposide may have immune-regulatory effects and prevent the formation of atherosclerotic lesions by decreasing the DC numbers, and inhibit DC maturation in bone marrow and infiltration into lesions.