Impaired synaptic plasticity and decreased glutamatergic neuron excitability induced by SIRT1/BDNF downregulation in the hippocampal CA1 region are involved in postoperative cognitive dysfunction.

BACKGROUND: Postoperative cognitive dysfunction (POCD) is a common complication after anesthesia/surgery, especially among elderly patients, and poses a significant threat to their postoperative quality of life and overall well-being. While it is widely accepted that elderly patients may experience POCD following anesthesia/surgery, the exact mechanism behind this phenomenon remains unclear. Several studies have indicated that the interaction between silent mating type information regulation 2 homologue 1 (SIRT1) and brain-derived neurotrophic factor (BDNF) is crucial in controlling cognitive function and is strongly linked to neurodegenerative disorders. Hence, this research aims to explore how SIRT1/BDNF impacts cognitive decline caused by anesthesia/surgery in aged mice. METHODS: Open field test (OFT) was used to determine whether anesthesia/surgery affected the motor ability of mice, while the postoperative cognitive function of 18 months old mice was evaluated with Novel object recognition test (NORT), Object location test (OLT) and Fear condition test (FC). The expressions of SIRT1 and other molecules were analyzed by western blot and immunofluorescence staining. The hippocampal synaptic plasticity was detected by Golgi staining and Long-term potentiation (LTP). The effects of SIRT1 and BDNF overexpression as well as chemogenetic activation of glutamatergic neurons in hippocampal CA1 region of 18 months old vesicular glutamate transporter 1 (VGLUT1) mice on POCD were further investigated. RESULTS: The research results revealed that older mice exhibited cognitive impairment following intramedullary fixation of tibial fracture. Additionally, a notable decrease in the expression of SIRT1/BDNF and neuronal excitability in hippocampal CA1 glutamatergic neurons was observed. By increasing levels of SIRT1/BDNF or enhancing glutamatergic neuron excitability in the CA1 region, it was possible to effectively mitigate synaptic plasticity impairment and ameliorate postoperative cognitive dysfunction. CONCLUSIONS: The decline in SIRT1/BDNF levels leading to changes in synaptic plasticity and neuronal excitability in older mice could be a significant factor contributing to cognitive impairment after anesthesia/surgery.

The role of epigenetic modification in postoperative cognitive dysfunction.

With the ageing of the population, the health problems of elderly individuals have become particularly important. Through a large number of clinical studies and trials, it has been confirmed that elderly patients can experience postoperative cognitive dysfunction after general anesthesia/surgery. However, the mechanism of postoperative cognitive dysfunction is still unknown. In recent years, the role of epigenetics in postoperative cognitive dysfunction has been widely studied and reported. Epigenetics includes the genetic structure and biochemical changes of chromatin not involving changes in the DNA sequence. This article summarizes the epigenetic mechanism of cognitive impairment after general anesthesia/surgery and analyses the broad prospects of epigenetics as a therapeutic target for postoperative cognitive dysfunction.

Roles and crosstalks of macrophages in diabetic nephropathy.

Diabetic nephropathy (DN) is the most common chronic kidney disease. Accumulation of glucose and metabolites activates resident macrophages in kidneys. Resident macrophages play diverse roles on diabetic kidney injuries by releasing cytokines/chemokines, recruiting peripheral monocytes/macrophages, enhancing renal cell injuries (podocytes, mesangial cells, endothelial cells and tubular epithelial cells), and macrophage-myofibroblast transition. The differentiation and cross-talks of macrophages ultimately result renal inflammation and fibrosis in DN. Emerging evidence shows that targeting macrophages by suppressing macrophage activation/transition, and macrophages-cell interactions may be a promising approach to attenuate DN. In the review, we summarized the diverse roles of macrophages and the cross-talks to other cells in DN, and highlighted the therapeutic potentials by targeting macrophages.

A patient with hereditary transthyretin amyloidosis involving multiple cranial nerves due to a rare p.(Phe84Ser) variant.

We report a 30-year-old man involving gastrointestinal symptoms, vitreous opacity, and multiple cranial neuropathies. Transthyretin-related hereditary amyloidosis genetic testing revealed a rare c.251T > C variant p.(Phe84Ser). Only four cases with this variant have been reported before.

The Effect of SIRT3/Ac-SOD2 Mediated Oxidative Stress and HCN1 Channel Activity on Anesthesia/Surgery Induced Anxiety-Like Behavior in Mice.

Anxiety disorders are the most common psychiatric diseases, and perioperative factors often increase the incidence of anxiety. However, the mechanism and treatment for perioperative anxiety, especially anesthesia/surgery-induced postoperative anxiety, are largely unknown. Sirtuin 3 (SIRT3) which located in the mitochondria is the NAD-dependent deacetylase protein. SIRT3 mediated oxidative stress is associated with several neuropsychiatric diseases. In addition, hyperpolarization-activated cyclic nucleotide-gated 1 (HCN1) channel is also reported involved in anxiety symptoms. The purpose was to assess the role of SIRT3 on postoperative anxiety like behavior in C57/BL6 mice. We found that SIRT3 level reduced and HCN1 expression level increased in mice medial prefrontal cortex (mPFC) as well as anxiety like behavior postoperatively. In interventional research, SIRT3 adeno-associated virus vector or control vector was injected into the mPFC brain region. Enzyme-linked immunosorbent assay, immunofluorescence staining, and western blotting were employed to detect oxidative stress reactions and HCN1 channel activity. SIRT3 overexpression attenuated postoperative anxiety in mice. Superoxide dismutase 2 (SOD2) acetylation levels, SOD2 oxidative stress activity, mitochondrial membrane potential levels, and HCN1 channels were also inhibited by SIRT3 overexpression. Furthermore, the HCN1 channel inhibitor ZD7288 significantly protected against anesthesia/surgery-induced anxiety, but without SIRT3/ac-SOD2 expression or oxidative stress changes. Our results suggest that SIRT3 may achieve antianxiety effects through regulation of SOD2 acetylation-mediated oxidative stress and HCN1 channels in the mPFC, further strengthening the therapeutic potential of targeting SIRT3 for anesthesia/surgery-induced anxiety-like behavior.

7-Hydroxycoumarin protects against cisplatin-induced acute kidney injury by inhibiting necroptosis and promoting Sox9-mediated tubular epithelial cell proliferation.

BACKGROUND: 7-Hydroxycoumarin (7-HC), also known as umbelliferon, is commonly found in Chinese herbs (e.g. Eucommiae Cortex, Prunellae Spica, Radix Angelicae Biseratae). Previous laboratory studies have indicated that 7-HC has anti-inflammatory, anti-oxidative, and anti-tumor effects. Cisplatin is a widely used chemotherapeutic agent for cancer. Nephrotoxicity is one of the limiting side effects of cisplatin use. PURPOSE: This study aimed to evaluate the renoprotective effect of 7-HC in a cisplatin-induced acute kidney injury (AKI) mouse model. METHODS: AKI was induced in male C57BL/6 mice (aged 6-8 weeks) by a single intraperitoneal injection of cisplatin at 20 mg/kg. The mice received 7-HC at 30, 60, and 90 mg/kg intraperitoneally before or after cisplatin administration. Renal function, necroptosis, and cell proliferation were measured. Mechanisms underlying the reno-protective effect of 7-HC were explored in renal tubular epithelial cells treated with or without cisplatin. RESULTS: In-vivo experiments showed that 7-HC significantly improved the loss in kidney function induced by cisplatin, as indicated by lower levels of serum creatinine and blood urea nitrogen, in AKI mice. Consistent herewith, cisplatin-induced tubular damage was alleviated by 7-HC as shown by morphological (periodic acid-Schiff staining) and kidney injury marker (KIM-1) analyses. We found that 7-HC suppressed renal necroptosis via the RIPK1/RIPK3/MLKL pathway and accelerated renal repair as evidenced by the upregulation of cyclin D1 in cisplatin-induced nephropathy. In-vitro experiments showed that knockdown of Sox9 attenuated the suppressive effect of 7-HC on KIM-1 and reversed the stimulatory effect of 7-HC on cyclin D1 expression in cisplatin-treated HK-2 cells, indicating that 7-HC may protect against AKI via a Sox9-dependent mechanism. CONCLUSION: 7-HC inhibits cisplatin-induced AKI by suppressing RIPK1/RIPK3/MLKL-mediated necroptosis and promoting Sox9-mediated tubular epithelial cell proliferation. 7-HC may serve as a preventive and therapeutic agent for AKI.

Alcohol promotes renal fibrosis by activating Nox2/4-mediated DNA methylation of Smad7.

Alcohol consumption causes renal injury and compromises kidney function. The underlying mechanism of the alcoholic kidney disease remains largely unknown. In the present study, an alcoholic renal fibrosis animal model was first employed which mice received liquid diet containing alcohol for 4 to 12 weeks. The Masson's Trichrome staining analysis showed that kidney fibrosis increased at week 8 and 12 in the animal model that was further confirmed by albumin assay, Western blot, immunostaining and real-time PCR of fibrotic indexes (collagen I and α-SMA). In vitro analysis also confirmed that alcohol significantly induced fibrotic response (collagen I and α-SMA) in HK2 tubular epithelial cells. Importantly, both in vivo and in vitro studies showed alcohol treatments decreased Smad7 and activated Smad3. We further determined how the alcohol affected the balance of Smad7 (inhibitory Smad) and Smad3 (regulatory Smad). Genome-wide methylation sequencing showed an increased DNA methylation of many genes and bisulfite sequencing analysis showed an increased DNA methylation of Smad7 after alcohol ingestion. We also found DNA methylation of Smad7 was mediated by DNMT1 in ethyl alcohol (EtOH)-treated HK2 cells. Knockdown of Nox2 or Nox4 decreased DNMT1 and rebalanced Smad7/Smad3 axis, and thereby relieved EtOH-induced fibrotic response. The inhibition of reactive oxygen species by the intraperitoneal injection of apocynin attenuated renal fibrosis and restored renal function in the alcoholic mice. Collectively, we established novel in vivo and in vitro alcoholic kidney fibrosis models and found that alcohol induces renal fibrosis by activating oxidative stress-induced DNA methylation of Smad7. Suppression of Nox-mediated oxidative stress may be a potential therapy for long-term alcohol abuse-induced kidney fibrosis.

Petchiether A attenuates obstructive nephropathy by suppressing TGF-ß/Smad3 and NF-κB signalling.

Obstructive nephropathy is the end result of a variety of diseases that block drainage from the kidney(s). Transforming growth factor-ß1 (TGF-ß1)/Smad3-driven renal fibrosis is the common pathogenesis of obstructive nephropathy. In this study, we identified petchiether A (petA), a novel small-molecule meroterpenoid from Ganoderma, as a potential inhibitor of TGF-ß1-induced Smad3 phosphorylation. The obstructive nephropathy was induced by unilateral ureteral obstruction (UUO) in mice. Mice received an intraperitoneal injection of petA/vehicle before and after UUO or sham operation. An in vivo study revealed that petA protected against renal inflammation and fibrosis by reducing the infiltration of macrophages, inhibiting the expression of proinflammatory cytokines (interleukin-1ß and tumour necrosis factor-α) and reducing extracellular matrix deposition (α-smooth muscle actin, collagen I and fibronectin) in the obstructed kidney of UUO mice; these changes were associated with suppression of Smad3 and NF-κB p65 phosphorylation. Petchiether A inhibited Smad3 phosphorylation in vitro and down-regulated the expression of the fibrotic marker collagen I in TGF-ß1-treated renal epithelial cells. Further, we found that petA dose-dependently suppressed Smad3-responsive promoter activity, indicating that petA inhibits gene expression downstream of the TGF-ß/Smad3 signalling pathway. In conclusion, our findings suggest that petA protects against renal inflammation and fibrosis by selectively inhibiting TGF-ß/Smad3 signalling.

ORP2 Delivers Cholesterol to the Plasma Membrane in Exchange for Phosphatidylinositol 4, 5-Bisphosphate (PI(4,5)P2).

Cholesterol is highly enriched at the plasma membrane (PM), and lipid transfer proteins may deliver cholesterol to the PM in a nonvesicular manner. Here, through a mini-screen, we identified the oxysterol binding protein (OSBP)-related protein 2 (ORP2) as a novel mediator of selective cholesterol delivery to the PM. Interestingly, ORP2-mediated enrichment of PM cholesterol was coupled with the removal of phosphatidylinositol 4, 5-bisphosphate (PI(4,5)P2) from the PM. ORP2 overexpression or deficiency impacted the levels of PM cholesterol and PI(4,5)P2, and ORP2 efficiently transferred both cholesterol and PI(4,5)P2in vitro. We determined the structure of ORP2 in complex with PI(4,5)P2 at 2.7 Å resolution. ORP2 formed a stable tetramer in the presence of PI(4,5)P2, and tetramerization was required for ORP2 to transfer PI(4,5)P2. Our results identify a novel pathway for cholesterol delivery to the PM and establish ORP2 as a key regulator of both cholesterol and PI(4,5)P2 of the PM.

Restoration of E-cadherin by PPBICA protects against cisplatin-induced acute kidney injury by attenuating inflammation and programmed cell death.

E-cadherin is a major component of tubular adherent proteins that maintain intercellular contacts and cell polarity in epithelial tissue. It is involved in pathological processes of renal cell carcinoma and fibrotic diseases via epithelial-mesenchymal transition. Although studies have shown E-cadherin is significantly downregulated in acute kidney injury (AKI), its function in AKI is unknown. Here, we evaluated cell damage and inflammation in cisplatin-stimulated tubular epithelial cell lines after disrupting E-cadherin and restoring it with PPBICA, a small molecule identified by high-throughput screening. We also determined the therapeutic potential of restoring E-cadherin in vivo. Results show cisplatin reduced E-cadherin expression both in mouse kidney and proximal tubular epithelial cell lines (mTECs). PPBICA restored E-cadherin levels, which increased cell viability while attenuating programmed cell death. This may be mediated via deactivation of the RIPK1/RIPK3 axis and decreased caspase3 cleavage. In addition, PPBICA suppressed inflammatory response in cisplatin-treated mTECs, which correlated with suppressed NF-κB phosphorylation and promoter activity. In contrast, disruption of E-cadherin promoted cell damage and inflammation. PPBICA failed to further attenuate kidney damage in E-cadherin knockdown cells, indicating that PPBICA protects against mTECs through E-cadherin restoration. We also found that peritoneal injection of PPBICA in mice prevented loss of renal function and tubular damage by suppressing NF-κB-driven renal inflammation and RIPK-regulated programmed cell death. This was driven by restoration of E-cadherin in cisplatin nephropathy. Additionally, PPBICA attenuated cisplatin-induced kidney damage in an established AKI model, indicating its therapeutic potential in the treatment of AKI. In conclusion, E-cadherin plays functional roles in tubule integrity, programmed cell death, and renal inflammation. Our results underscore the potential of E-cadherin restoration as a novel therapeutic strategy for AKI.

Wogonin protects against cisplatin-induced acute kidney injury by targeting RIPK1-mediated necroptosis.

Acute kidney injury (AKI), characterized by aggressive inflammatory responses and destruction of renal resident cells, can cause abrupt kidney dysfunction. To date, effective therapy for AKI is lacking. In this study, we evaluated the renoprotective effect of wogonin, an herbal active compound, using a cisplatin-induced AKI mouse model. In vivo results show that wogonin substantially suppressed the increased levels of serum creatinine and blood urea nitrogen (BUN) almost to the normal level. Wogonin also attenuated tubular damage, shown by PAS staining, electron microscopy and molecular analysis of KIM-1. In addition, wogonin suppressed kidney inflammation as indicated by a >60% decrease in macrophage infiltration, a >50% reduction in inflammatory cytokine production and inhibited NF-κB activation in the injured kidney. Mechanistically, molecular docking results show that wogonin effectively inhibited RIPK1 by occupying the ATP-binding pocket of the enzyme, which is a key regulator of necroptosis. Moreover, inhibition of RIPK1, or RIPK3, reversed the protective effects of wogonin in cisplatin-treated HK2 cells, indicating wogonin works in a RIPK1/RIPK3-dependent manner. Surprisingly, wogonin enhanced the anti-proliferative effect of cisplatin on human hepatoma HepG2 cells. Thus, our findings suggest wogonin may be a renoprotective adjuvant for cisplatin-based anticancer therapy.

NADPH oxidase 4 promotes cisplatin-induced acute kidney injury via ROS-mediated programmed cell death and inflammation.

The goal of this study was to elucidate the functional role of Nox4 during acute kidney injury (AKI). NADPH oxidases are a major source of reactive oxygen species (ROS) in the kidney in normal and pathological conditions. Among NADPH oxidase isoforms, NADPH oxidase4 (Nox4) is highly expressed in the kidney and has an important role in kidney diseases, such as diabetic nephropathy and renal carcinoma. We previously found that Nox4 expression significantly increased in the toxic AKI model. However, its functional role and mechanism of action in AKI are still unknown. We scavenged ROS with apocynin in vitro and in vivo and found it attenuated cisplatin-triggered renal function decline. It also alleviated programmed cell death and renal inflammation, indicating a critical role for ROS in mediating AKI. Nox4 protein and mRNA levels were substantially upregulated by cisplatin in vivo and in vitro. Nox4 knockdown alleviated cisplatin-induced cell death and inflammatory response, while Nox4 overexpression aggravated them. Moreover, N-acetyl-L-cysteine (NAC)-mediated inhibition of ROS suppressed cell injury led by Nox4 overexpression, indicating Nox4-mediated ROS generation may be the key mediator in cisplatin-induced nephrotoxicity. Mechanistically, excessive expression of Nox4 induced programmed cell death, especially RIP-mediated necroptosis. Finally, we tested whether Nox4 is a potential therapeutic target using an AKI mouse model by injecting a lentivirus-packaged Nox4 shRNA plasmid through tail vein. Disruption of Nox4 led to renal function recovery, kidney damage relief and reduced inflammation. We conclude that Nox4 aggravates cisplatin-induced nephrotoxicity by promoting ROS-mediated programmed cell death and inflammation. Thus Nox4 may serve as a potential therapeutic target in the treatment of AKI.

Effect of entecavir in the treatment of patients with hepatitis B virus-related compensated and decompensated cirrhosis.

Chronic hepatitis B virus (CHB) infection is a burden on global healthcare and is associated with a higher risk of serious sequelae, including cirrhosis and hepatocellular carcinoma. The clinical application of entecavir as a treatment for CHB has produced positive outcomes, and so is an attractive form of pharmacological therapy. However, little data exists comparing the safety and efficacy of entecavir for the treatment of hepatitis B virus (HBV)-related compensated, and decompensated cirrhosis, respectively. The aim of the present study was to evaluate entecavir therapy as a treatment for patients with HBV-related compensated and decompensated cirrhosis. A retrospective analysis of 46 compensated patients (compensated group) and 51 decompensated cirrhotic patients (decompensated group) treated with entecavir was conducted. Baseline demographics, clinical outcomes, and adverse events during the treatment were compared. Treatment with entecavir for 96 weeks resulted in significant improvements in serum levels of HBV DNA (P=0.002), albumin (P=0.014), cholinesterase (CHE; P=0.001), HBV DNA negativity rate (P=0.004), Child-Turcotte-Pugh score (P=0.030), alanine aminotransferase normalized rate (P=0.039), and the degree of esophageal varices liver stiffness (P=0.002) in the two groups. However, statistical analysis revealed that the improvements were significantly higher in the compensated group compared with the decompensated group (P<0.05). The complement component (C)3 and C4 levels were also significantly increased in the compensated group compared with the decompensated group at weeks 24, 48 and 96 (P<0.05). In addition, the incidences of hepatocellular carcinoma, upper digestive tract hemorrhage and ascites were significantly higher in the decompensated group compared with the compensated group (P<0.05). In conclusion, treatment with 96-week entecavir therapy produced similar clinical outcomes in compensated and decompensated cirrhotic patients via inhibiting HBV-DNA viral load and recovering complement C3 and C4; however, entecavir exerts a better effect on patients with compensated cirrhosis, and so this therapy may improve the prognosis of such patients.

Protocatechuic Aldehyde Attenuates Cisplatin-Induced Acute Kidney Injury by Suppressing Nox-Mediated Oxidative Stress and Renal Inflammation.

Cisplatin is a classic chemotherapeutic agent widely used to treat different types of cancers including ovarian, head and neck, testicular and uterine cervical carcinomas. However, cisplatin induces acute kidney injury by directly triggering an excessive inflammatory response, oxidative stress, and programmed cell death of renal tubular epithelial cells, all of which lead to high mortality rates in patients. In this study, we examined the protective effect of protocatechuic aldehyde (PA) in vitro in cisplatin-treated tubular epithelial cells and in vivo in cisplatin nephropathy. PA is a monomer of Traditional Chinese Medicine isolated from the root of S. miltiorrhiza (Lamiaceae). Results show that PA prevented cisplatin-induced decline of renal function and histological damage, which was confirmed by attenuation of KIM1 in both mRNA and protein levels. Moreover, PA reduced renal inflammation by suppressing oxidative stress and programmed cell death in response to cisplatin, which was further evidenced by in vitro data. Of note, PA suppressed NAPDH oxidases, including Nox2 and Nox4, in a dosage-dependent manner. Moreover, silencing Nox4, but not Nox2, removed the inhibitory effect of PA on cisplatin-induced renal injury, indicating that Nox4 may play a pivotal role in mediating the protective effect of PA in cisplatin-induced acute kidney injury. Collectively, our data indicate that PA blocks cisplatin-induced acute kidney injury by suppressing Nox-mediated oxidative stress and renal inflammation without compromising anti-tumor activity of cisplatin. These findings suggest that PA and its derivatives may serve as potential protective agents for cancer patients receiving cisplatin treatment.

Anti-fibrotic effect of wogonin in renal tubular epithelial cells via Smad3-dependent mechanisms.

Renal fibrosis, a common feature and leading cause for End Stage Renal Disease, still lacks effective therapy. In the current study, we detected and compared the anti-fibrotic effects of wogonin and wogonoside, two major components of Scutellaria baicalensis Georgi, in TGF-ß1-treated tubular epithelial cells of human and murine origins. Results consistently showed that compared with wogonoside, wogonin inhibits TGF-ß1-induced upregulated mRNA and protein levels of collagen I and α-SMA with more efficiency, which was further confirmed by the immunofluorescence results that wogonin decreased the percentage of collagen I and α-SMA positive cells in TGF-ß1-treated tubular epithelial cells. Mechanistically, wogonin mainly decreased Smad3 phosphorylation, but had marginal effect on non-canonical TGF-ß signaling pathways, such as p38 and ERK MAP Kinase. Furthermore, in the cells deficient for TGF-ß signaling or downstream Smad3, results demonstrated that even high concentration of wogonin failed to further decrease the level of collagen I and α-SMA, indicating the essential role of TGF-ß/Smad3 signaling inhibition in the therapeutic action of wogonin in TGF-ß1-stimulated tubular epithelial cells. Collectively, our results indicated that wogonin may be utilized as a potential anti-fibrotic Traditional Chinese Medicine monomer in the treatment of renal fibrosis.

Dilator method and needle method for atrial transseptal puncture: a retrospective study from a cohort of 4443 patients.

AIMS: To compare the safety and efficacy of a new dilator method vs the traditional needle method for transseptal puncture (TSP) in a large cohort study. METHODS AND RESULTS: From February 1995 to December 2010, 4443 consecutive patients undergoing TSP done either by a needle method or by a new dilator method were reviewed retrospectively. Data as procedure-related time and complications were evaluated. For the standard needle method, TSP was performed by extending out the needle. In comparison, for the new dilator technique, TSP was performed without an outer sheath and with the needle kept within the dilator; the blunt tip of the dilator was used to help locating the position of the fossa ovalis on purpose. Transseptal puncture was performed by the new dilator method in 2151 patients (48.4%) and by the traditional needle method in 2292 patients (51.6%). The average TSP time needed by the dilator method was longer than that needed by the needle method (5.6 ± 3.9 vs. 3.8 ± 2.9 min, P< 0.05). Additional left atrial angiography was required in seven (0.33%) patients for the dilator and in 39 patients (1.70%) for the needle method (P< 0.05). The total rate of severe complications and obvious TSP-related complications was significantly lower in patients who underwent the dilator method than in those who underwent the needle method (0.33 vs. 1.18%, and 0.20 vs. 1.00%, respectively, P < 0.05). CONCLUSION: Our data suggest that the new dilator technique is much safer than that of the standard needle method. It needs relatively longer procedure time but results in significantly fewer episodes of severe complications. Particularly, the blunt tip of the dilator can be used to help locate the fossa ovalis. Therefore, the new dilator technique might be a better choice for relatively less-experienced operators.

[Association between myocardial calpain activation and apoptosis in lipopolysaccharide-induced septic mouse model].

OBJECTIVE: in septic mice, myocardial calpain was activated and induced caspase-3 activation, the association between calpain activation and apoptosis was explored in this experiment. METHODS: in in vivo model, adult C57 mice were injected with lipopolysaccharide (LPS, 4 mg/kg, i.p.) to induce sepsis. Myocardial calpain and caspase-3 activities, protein levels of calpain-1, calpain-2, calpastatin, Bcl-2 and Bid were detected by Western blot analysis and myocardial apoptosis was detected by TUNEL, myocardiac function was evaluated by Langendorff system. In in vitro model, adult rat cardiomyocytes were incubated with LPS (1 microg/ml) or co-incubated with calpain inhibitor-III (10 micromol/L), calpain activity, caspase-3 activity, protein levels of Bcl-2 and Bid, and cardiomyocyte apoptosis were detected. RESULTS: in septic mice, myocardial calpain and caspase-3 activity were increased up to 2.7- and 1.8-folds, respectively. Both calpain inhibitor-III and PD150606 significantly attenuated the increase of caspase-3 activity. Myocardial protein levels of calpain-1, calpain-2, calpastatin, Bcl-2 and Bid were similar between control and septic mice, and no cleavage of both Bcl-2 and Bid was found in septic mice. Calpain inhibitor-III significantly improved myocardial function in septic mice. In in vitro model, calpain and caspase-3 activities were increased after 4 h LPS treatment, co-treatment with calpain inhibitor-III prevented caspase-3 activity increase, protein Bcl-2 and Bid were similar between normal cardiomyocytes and LPS-treated cardiomyocytes. Cardiomyocyte apoptosis was similar in in vivo and in vitro septic models. CONCLUSION: myocardial calpain activity is increased in LPS induced septic mice, subsequent caspase-3 activation may contribute to myocardial dysfunction in septic mice without aggravating myocardial apoptosis and Bcl-2 and Bid are not involved on calpain induced caspase-3 activation in our model.

[Comparison of peripheral blood hematopoietic progenitor cells among patients with paroxysmal, permanent atrial fibrillation or sinus rhythm].

OBJECTIVE: To compare peripheral blood hematopoietic progenitor cells (HPCs), plasma atrial natriuretic peptide (ANP) and stromal cell-derived factor-1alpha (SDF-1alpha) among patients with paroxysmal, permanent atrial fibrillation (AF) or sinus rhythm. METHODS: Peripheral blood concentration of CD34+HPCs were quantified by flow cytometric analysis (FCM), plasma ANP levels were measured by radioimmunoassay (RIA) method, plasma levels of SDF-1alpha were determined by enzyme linked immunosorbent assay (ELISA) in 30 patients with permanent AF, 28 patients with paroxysmal AF, and 30 patients with sinus rhythm (SR). HPCs were separated, cultured and stained for ANP by the use of alkaline phosphatase-anti-alkaline phosphatase technique (APAAP) in 30 patients (10 from each group). RESULTS: (1) The number of CD34+HPCs in permanent AF group [(5.31 +/- 1.67) x 10(6)/L] were significantly higher comparing to paroxysmal AF group [(2.33 +/- 1.29) x 10(6)/L] (P < 0.05) and SR group [(2.03 +/- 0.64) x 10(6)/L] (P < 0.05) while CD34+HPCs was similar between paroxysmal AF group and SR group (P > 0.05). (2) Plasma levels of ANP (0.312 +/- 0.121) microg/L and SDF-1alpha (3210.2 +/- 1234.7) ng/L were also significantly higher in permanent AF group than paroxysmal AF group and SR group (all P < 0.05) and were similar in paroxysmal AF group and SR group (all P > 0.05). (3) The plasma levels of ANP and SDF-1alpha were both positive correlated with peripheral blood concentration of CD34+HPCs (r = 0.783, P < 0.01; r = 0.427, P < 0.01). (4) After 3 days of culture, ANP was weakly expressed in HPCs from patients with permanent AF but not from patients with paroxysmal AF and SR. CONCLUSIONS: Peripheral blood HPCs together with plasma ANP and SDF-1alpha were significantly increased in patients with permanent AF. CD34+HPCs were positive correlated with the plasma levels of ANP and SDF-1alpha.