Mechanism of Qili Qiangxin Capsule for Heart Failure Based on miR133a-Endoplasmic Reticulum Stress.

OBJECTIVE: To investigate the pharmacological mechanism of Qili Qiangxin Capsule (QLQX) improvement of heart failure (HF) based on miR133a-endoplasmic reticulum stress (ERS) pathway. METHODS: A left coronary artery ligation-induced HF after myocardial infarction model was used in this study. Rats were randomly assigned to the sham group, the model group, the QLQX group [0.32 g/(kg·d)], and the captopril group [2.25 mg/(kg·d)], 15 rats per group, followed by 4 weeks of medication. Cardiac function such as left ventricular ejection fraction (EF), fractional shortening (FS), left ventricular systolic pressure (LVSP), left ventricular end diastolic pressure (LVEDP), the maximal rate of increase of left ventricular pressure (+dp/dt max), and the maximal rate of decrease of left ventricular pressure (-dp/dt max) were monitored by echocardiography and hemodynamics. Hematoxylin and eosin (HE) and Masson stainings were used to visualize pathological changes in myocardial tissue. The mRNA expression of miR133a, glucose-regulated protein78 (GRP78), inositol-requiring enzyme 1 (IRE1), activating transcription factor 6 (ATF6), X-box binding protein1 (XBP1), C/EBP homologous protein (CHOP) and Caspase 12 were detected by RT-PCR. The protein expression of GRP78, p-IRE1/IRE1 ratio, cleaved-ATF6, XBP1-s (the spliced form of XBP1), CHOP and Caspase 12 were detected by Western blot. TdT-mediated dUTP nick-end labeling (TUNEL) staining was used to detect the rate of apoptosis. RESULTS: QLQX significantly improved cardiac function as evidenced by increased EF, FS, LVSP, +dp/dt max, -dp/dt max, and decreased LVEDP (P<0.05, P<0.01). HE staining showed that QLQX ameliorated cardiac pathologic damage to some extent. Masson staining indicated that QLQX significantly reduced collagen volume fraction in myocardial tissue (P<0.01). Results from RT-PCR and Western blot showed that QLQX significantly increased the expression of miR133a and inhibited the mRNA expressions of GRP78, IRE1, ATF6 and XBP1, as well as decreased the protein expressions of GRP78, cleaved-ATF6 and XBP1-s and decreased p-IRE1/IRE1 ratio (P<0.05, P<0.01). Further studies showed that QLQX significantly reduced the expression of CHOP and Caspase12, resulting in a significant reduction in apoptosis rate (P<0.05, P<0.01). CONCLUSION: The pharmacological mechanism of QLQX in improving HF is partly attributed to its regulatory effect on the miR133a-IRE1/XBP1 pathway.

Thiazolidinediones play a positive role in the vascular endothelium and inhibit plaque progression in diabetic patients with coronary atherosclerosis: A systematic review and meta-analysis.

Rosiglitazone (Avandia) and pioglitazone (Actos) belong to the class of thiazolidinediones (TZDs) drugs that act by increasing insulin sensitivity and are widely used for treating diabetic patients with insulin resistance. TZDs exhibit anti-inflammatory and antioxidant properties, then may play an active role in inhibiting plaque formation and coronary atherosclerosis. But the results of evidence-based medicine suggest that TZDs may increase the risk of cardiovascular adverse events. To explore the dispute in depth, our meta-analysis aimed to evaluate the changes in vascular endothelial and plaque-related indicators following treatment with TZDs in diabetic patients with coronary atherosclerosis. According to our meta-analysis, TZDs showed an inhibiting effect on plaque progression and a protective effect on the vascular endothelium in patients with diabetes and coronary atherosclerosis. Interestingly, these effects may not depend on the regulation of inflammation and lipid metabolism. By this token, TZDs may develop a potential protective effect on myocardial infarction. Systematic review registration: [https://www.crd.york.ac.uk/prospero/], identifier [CRD42021231663].

Comparative Pharmacokinetics of Seven Major Compounds in Normal and Atherosclerosis Mice after Oral Administration of Simiao Yong'an Decoction.

Simiao Yong'an decoction (SMYAD), a classic traditional Chinese medicine formula, has been used to treat atherosclerosis (AS) in clinical in China, but its therapeutic mechanism and pharmacodynamic material basis are not clear. In this study, the AS model was caused by a high-fat diet and perivascular carotid collar placement (PCCP), and SMYAD was orally administered to the model and normal mice. A rapid, sensitive, selective, and reliable method using ultrahigh-performance liquid chromatography (UHPLC) system combined with a Q Exactive HF-X mass spectrometer (UHPLC-Q Exactive HF-X MS) was established and validated for the simultaneous determination of seven compounds, including harpagide, chlorogenic acid, swertiamarin, sweroside, angoroside C, liquiritin, and isoliquiritigenin in the plasma of normal and AS mice. The specificity, linearity, precision, accuracy, recovery, and stability of the method were all within the acceptable criteria. The results showed that some pharmacokinetic behaviors of harpagide, chlorogenic acid, and isoliquiritigenin were significantly different among the two groups of mice. The specific parameter changes were harpagide (AUC0-t and AUC0-∞ were 11075.09 ± 2132.38 and 16221.95 ± 5622.42 ng·mL-1·h, respectively; CLz/F was 2.45 ± 0.87 L/h/mg), chlorogenic acid (t 1/2 was 21.59 ± 9.16 h; AUC0-∞ was 2637.51 ± 322.54 ng·mL-1·h; CLz/F was 13.49 ± 1.81 L/h/mg) and isoliquiritigenin (AUC0-t and AUC0-∞ were 502.25 ± 165.65 and 653.68 ± 251.34 ng·mL-1·h, respectively; CLz/F was 62.16 ± 23.35 L/h/mg) were altered under the pathological status of AS. These differences might be partly ascribed to the changes in gastrointestinal microbiota, nonspecific drug transporters, and cytochrome P450 activity under the AS state, providing research ideas and experimental basis for pharmacological effects and pharmacodynamic material basis.

Socio-economic disparity in visual impairment from cataract.

AIM: To investigate the association of visual impairment from cataract with human development index (HDI) by years lived with disability (YLDs). METHODS: Published data on national age-standardized YLD rates caused by cataract and national HDIs in 2019 were obtained. Age-standardized YLD rates from 1990 to 2019 were analyzed to explore cataract burden among patients with different income levels. Age-standardized YLD rates in different HDI groups were compared by different degrees of visual impairment. Association between national age-standardized YLD rates and HDI in 2019 was analyzed. RESULTS: The age-standardized YLD rates of populations with visual impairment or blindness due to cataract declined from 1990 to 2019, especially among those with lower middle income. Multiple comparison tests revealed that countries with low HDI had significantly higher age-standardized YLD rates of blindness due to cataract than those with high and very high HDI (P<0.001). The age-standardized YLD rates of populations with blindness (ß=-0.588, P<0.001), severe vision loss (ß=-0.378, P<0.001), and moderate vision loss (ß=-0.389, P<0.001) inversely correlated with HDI. CONCLUSION: Age-standardized YLD rates caused by cataract have declined since 1990. The burden of visual impairment due to cataract inversely correlate with national socioeconomic development and is more concentrated in countries with low HDI than those with high HDI, especially among the blind. These findings highlight the need to provide additional cataract services and cataract surgery coverage to developing countries to decrease the burden of avoidable blindness caused by cataract.

[Huotan Jiedu Tongluo decoction alleviates early atherosclerosis of rabbits by inhibiting eNOS uncoupling pathway].

The aim of this paper was to study the curative effect of Huotan Jiedu Tongluo (HTJDTL) decoction on a rabbit model with early atherosclerosis (AS),and furtherly to explore whether it could inhibit the BH4/eNOS uncoupling ROS or not. Twenty-four Japanese white rabbits were randomly divided into sham operation group, model group, HTJDTL decoction group and atorvastatin group. Rabbit models with early atherosclerosis were established by high fat diet, nitrogen drying and carotid artery balloon injury. The rabbits were sacrificed at 7th days after balloon injury and several parameters were measured. The pathological morphology of the common carotid artery was observed by HE staining. The blood lipids were detected by peroxidase method. The ratio of vascular eNOS dimer and monomer was measured by Western blot. The ELISA and biochemical technology were respectively used for testing BH4 and ROS levels in serum. The results showed that compared with the sham operation group, the model group had mild stenosis of the common carotid artery lumen, uneven intimal hyperplasia, lipid deposition in the intima and media, and obvious hyperplasia of the adventitia with inflammatory cell infiltration. The HTJDTL decoction could significantly inhibit the intimal hyperplasia compared with the model group, meanwhile, reduce the lipid deposition of the media and the infiltration of the adventitial cells. Compared with the sham operation group, the blood lipids and ROS of the model animals significantly increased, but BH4 and the ratio of eNOS dimer/monomer decreased. Compared with the model group, HTJDTL decoction significantly reduced the TC, ox-LDL and ROS levels, and also up-regulated eNOS dimer/monomer ratio, but it increased BH4 trend without statistical difference. According to the results, it was found that HTJDTL decoction couldsignificantly prevent and improve the vascular remodeling of rabbits model with early atherosclerosis. The mechanism of decoction may largely be related to the inhibition of BH4/eNOS uncoupling and the reduction of oxidative stress.

National HIV/AIDS mortality, prevalence, and incidence rates are associated with the Human Development Index.

BACKGROUND: HIV/AIDS is a worldwide threat to human health with mortality, prevalence, and incidence rates varying widely. We evaluated the association between the global HIV/AIDS epidemic and national socioeconomic development. METHODS: We obtained global age-standardized HIV/AIDS mortality, prevalence, and incidence rates from World Health Statistics Report of the World Health Organization. The human development indexes (HDIs) of 141 countries were obtained from a Human Development Report. Countries were divided into 4 groups according to the HDI distribution. We explored the association between HIV/AIDS epidemic and HDI information using Spearman correlation analysis, regression analysis, and the Kruskal-Wallis test. RESULTS: HIV/AIDS mortality, prevalence, and incidence rates were inversely correlated with national HDI (r = -0.675, -0.519, and -0.398, respectively; P < .001), as well as the 4 indicators of HDI (ie, life expectancy at birth, mean years of schooling, expected years of schooling, and gross national income per capita). Low HDI countries had higher HIV/AIDS mortality, prevalence, and incidence rates than that of medium, high, and very high HDI countries. Quantile regression results indicated that HDI had a greater negative effect on the HIV/AIDS epidemic in countries with more severe HIV/AIDS epidemic. CONCLUSIONS: Less-developed countries are likely to have more severe HIV/AIDS epidemic. There is a need to pay more attention to HIV/AIDS control in less-developed countries, where lower socioeconomic status might have accelerated the HIV/AIDS epidemic more rapidly.

The relationship between hepatic lipase gene variant and advanced age-related macular degeneration: a meta-analysis.

IMPORTANCE: To date, no consistency exists across studies that have evaluated the relationship between hepatic lipase gene (LIPC) rs10468017 variant and advanced age-related macular degeneration (AMD). OBJECTIVE: To summarize all relevant evidence for a relationship between LIPC variant and advanced AMD. DATA SOURCES: The PubMed and Embase databases were searched for studies potentially eligible in any language published up to September 15, 2013. STUDY SELECTION: Case-control studies of 2 or more comparison groups that included patients with advanced AMD (choroidal neovascularization or geographic atrophy). DATA EXTRACTION AND SYNTHESIS: Allele frequencies and genotype distributions of rs10468017 variant. MAIN OUTCOMES AND MEASURES: Summary odds ratios (ORs) and 95% CIs were estimated under different genetic models using meta-analytic methods. A stratified analysis by advanced AMD subtypes and race/ethnicity was performed, as well as a sensitivity analysis. RESULTS: Data from 10 case-control studies were included in the meta-analysis. The rs10468017 variant (C→T) showed significant summary ORs of 0.81 (95% CI, 0.75-0.88), 0.83 (95% CI, 0.70-0.98), and 0.60 (95% CI, 0.44-0.81) under the allelic (T vs C), heterozygous (TC vs CC), and homozygous (TT vs CC) models, respectively. Carrying at least 1 copy of the T allele decreased the risk of choroidal neovascularization and geographic atrophy by 20% (OR, 0.80; 95% CI, 0.74-0.87) and 29% (OR, 0.71; 95% CI, 0.59-0.86), respectively. The pooled OR for white race/ethnicity under an allelic model was 0.80 (95% CI, 0.74-0.87). The sensitivity analysis indicated the robustness of our findings, and no evidence of publication bias was observed in our meta-analysis. CONCLUSIONS AND RELEVANCE: Our meta-analysis indicates that LIPC rs10468017 variant is associated with a reduced risk of advanced AMD. This finding may lead to insights regarding the pathogenesis, prevention, and treatment of AMD.

[Effect of Yishen Daluo Decoction on the expression of PLP, Olig1, and Olig2 in mice with experimental autoimmune encephalomyelitis].

OBJECTIVE: To study the effect of Yishen Daluo Decoction (YDD) on the expression of protein lipoprotein (PLP), oligodendrocyte transcription factor 1 (Olig 1), and oligodendrocyte transcription factor 2 (Olig2) in mice with experimental autoimmune encephalomyelitis (EAE). METHODS: Totally 40 mice were randomly divided into 4 groups, i.e., the normal group, the model group, the Chinese medicine (CM) group, and the Western medicine (WM) group, 10 mice in each group. Each mouse in the model, CM, and WM groups was subcutaneously injected with 200 microL antigen emulsion (containing 150 micro g PLP139 -151 and 400 micro g H37RA) in two parts at the upper abdomen on the first day. 100 microLBordetella pertussis juice (containing 0. 6 x 10(6) Bordetella pertussis) was injected by caudal vein on the first and the third day. On the 7th day after modeling, each mouse in the normal group and the model group was intragastrically given normal saline (0. 1 mL/10 g). YDD (0. 2 g crude drug/10 g) was intragastrically given to mice in the CM group, and prednisone (0. 039 mg/10 g) was intragastrically given to mice in the WM group. All mice were intervened for 54 days. Changes of PLP, Olig1, and Olig2 in the brain tissue of EAE mice were detected by Western blot. Results The levels of PLP and Olig2 in the brain tissue of the model group were less than those of the normal group (P <0.05). Compared with the model group, the levels of PLP, Olig1, and Olig2 in the brain tissue increased in the CM group (P <0.05); the levels of PLP and Olig2 in the brain tissue increased in the WM group (P <0.05). Compared with the WM group, the level of Olig1 in the brain tissue increased in the CM group (P <0.05). CONCLUSION: YDD could enhance remyelination by elevating the levels of Olig1 and Olig2 in the brain tissue of EAE mice.

Yiqi Huoxue Recipe Improves Heart Function through Inhibiting Apoptosis Related to Endoplasmic Reticulum Stress in Myocardial Infarction Model of Rats.

Objective. To explore the mechanism of cardioprotective effects of Chinese medicine, Yiqi Huoxue recipe, in rats with myocardial infarction- (MI-) induced heart failure. Methods. Male Sprague-Dawley rats underwent left anterior descending artery (LAD) ligation or sham operation. The surviving MI rats were divided randomly into three groups: MI (5 mL/kg/d NS by gavage), MI + Metoprolol Tartrate (MT) (12 mg/kg/d MT by gavage), and MI + Yiqi Huoxue (5 mL/kg recipe by gavage). And the sham operation rats were given 5 mL/kg/d normal saline. Treatments were given on the day following surgery for 4 weeks. Then rats were detected for heart structure and function by transthoracic echocardiography. Apoptosis in heart tissues was detected by TUNEL staining. To determine whether the endoplasmic reticulum (ER) stress response pathway is included in the cardioprotective function of the recipe, ER stress related proteins such as GRP78 and caspase-12 were examined. Results. Yiqi Huoxue recipe attenuated heart function injury, reversed histopathological damage, alleviated myocardial apoptosis and inhibited ER stress in MI rats. Conclusion. All the results suggest that Yiqi Huoxue recipe improves the injured heart function maybe through inhibition of ER stress response pathway, which is a promising target in therapy for heart failure.

Body mass index and risk of age-related cataract: a meta-analysis of prospective cohort studies.

BACKGROUND: Age-related cataract (ARC) is the leading cause of blindness in the world. The relationship between body mass index (BMI) and risk of ARC is controversial across observational studies. We therefore performed this meta-analysis to evaluate the association between BMI and risk of ARC. METHODS: Eligible studies were identified through an electronic search of PubMed, Embase and the Cochrane Library. We pooled study-specific relative risks (RRs) and 95% confidence intervals (CIs) to determine the risk of ARC associated with BMI categories and per 1 kg/m² increase in BMI. RESULTS: A total of 17 prospective cohort studies were included in the meta-analysis. The pooled RRs of ARC were 1.08 (95% CI, 1.01-1.16) for overweight and 1.19 (95% CI, 1.10-1.28) for obesity compared with normal weight. These findings were robust when stratified by sex, sample source, outcome types and confounders, while significantly differed by assessment of BMI and ARC, and duration of follow-up. The summary RR suggested that per 1 kg/m² increase in BMI was associated with a 2% increased risk of ARC (RR 1.02, 95% CI 1.01-1.03). Pooled estimates of RRs consistently indicated a trend for subjects with a high BMI to develop posterior subcapsular cataracts (RR 1.19, 95% CI 1.06-1.35, for overweight; RR 1.50, 95% CI 1.24-1.81, for obesity; RR 1.04, 95% CI 1.01-1.06, per 1 kg/m² increase in BMI) other than nuclear or cortical cataracts. CONCLUSIONS: The overall findings suggest that elevated BMI may increase the risk of ARC, especially posterior subcapsular cataracts. Further trials are needed to investigate the effect of weight reduction in obese populations on the risk of ARC.

Association between aspirin use and age-related macular degeneration: a meta-analysis.

PURPOSE: We conducted a meta-analysis of randomized controlled trials (RCTs) and observational studies to evaluate the association between aspirin use and age-related macular degeneration (AMD). METHODS: The pertinent studies were identified via literature search through four databases (MEDLINE, Web of Science, Cochrane Library, Embase) and reference lists of retrieved studies. Randomized controlled trials and cohort and case-control studies meeting the predefined criteria were included. We extracted relative risk (RR) or odds ratio (OR) or hazard ratio (HR) and 95% confidence interval (CI) from each study. Overall and study-specific risk estimates were pooled using fixed-effects and random-effects models, respectively. Subgroup analyses based on several stratified factors were also performed. RESULTS: In total, two RCTs, three cohort studies, and four case-control studies involving 177,683 subjects were included. The pooled effect of all nine studies showed no significant association between aspirin use and occurrence of AMD (RR, 1.00; 95% CI 0.96-1.04), and no significant association was observed in any specific study design (RR, 0.93; 95% CI 0.71-1.22 for RCT; RR, 1.02; 95% CI 0.87-1.20 for cohort study; RR, 1.00; 95% CI 0.96-1.04 for case-control study). However, subgroup analysis showed aspirin use to be significantly associated with an increased risk of neovascular AMD (RR, 1.59; 95% CI 1.09-2.31). CONCLUSIONS: The pooled effects from current literature suggest that aspirin use is not associated with AMD, but it increased the risk of the neovascular form of AMD.

[Effects of Astragalus membranaceus and Potentilla discolor mixture on insulin resistance and its related mRNA expressions in KKAy mice with type 2 diabetes].

OBJECTIVE: To investigate the effects of Astragalus membranaceus and Potentilla discolor mixture (APM) on insulin resistance (IR) and mRNA expressions of IR-related genes, including phosphatidylinositol 3-kinase (PI3-K), phosphoenolpyruvate carboxykinase (PEPCK) and peroxisome proliferator-activated receptor γ coactivator 1 (PGC1) in KKAy mice with early type 2 diabetes and to explore the gene regulation mechanisms of AMP. METHODS: After giving short-term high-fat and high-calorie diet to induce type 2 diabetes, male KKAy mice were randomly divided into model and APM groups. Nine C57BL/6J mice were used as normal control in addition. The mice in the APM group were treated with 830 g/L of the APM liquid by gastric infusion while the mice in the model group and the normal control group were given 0.05% sodium carboxymethyl cellulose at a dose of 0.1 mL/g body weight once per day. After four weeks, fasting plasma glucose (FPG) was tested using tail vein blood. Fasting serum insulin (FINS) was tested by radioimmunoassay. Insulin sensitivity index (ISI) was calculated as the natural logarithm of the product of FPG and FINS. The mRNA expressions of PI3-K, PEPCK and PGC1 in liver tissues were tested by real-time fluorescence quantitative polymerase chain reaction assay. RESULTS: Both the levels of FPG and FINS in the model group and the APM group were increased, while the ISI values were decreased when compared to those of the normal control group (P<0.01). The level of FPG in the APM group was decreased, while ISI was increased when compared to those of the model group (P<0.05). All of the mRNA expressions of PI3-K, PEPCK, and PGC1 in liver tissue of the model group were decreased compared with the normal control group (P<0.01). The mRNA expressions of PI3-K and PGC1 in the liver tissue of the APM group were higher than those in the model group (P<0.05). CONCLUSION: APM can improve the insulin resistance of mice with type 2 diabetes. The mechanism may be related to increasing the mRNA expressions of PI3-K and PGC1 in the liver tissue.

[Effects of Chinese herbal medicines Shengmai injection and Xuesaitong injection on ventricular fibrillation threshold and connexin 43 expression in rats with myocardial infarction].

OBJECTIVE: To explore the effects of Shengmai injection and Xuesaitong injection, compound Chinese herbal medicines for replenishing qi and activating blood, on ventricular fibrillation threshold, heart structure and connexin 43 (Cx43) expression in rats with myocardial infarction (MI). METHODS: One hundred male SD rats were randomly divided into sham operation group, model group, Yiqi Huoxue (YQHX) group (Shengmai injection plus Xuesaitong injection) and captopril group. MI model of rats was established by ligating left anterior descending coronary artery, and rats in sham operation group were prepared in the same way except for the ligation of coronary artery. Rats were treated with corresponding drugs for 1 month from next day after modeling. After treatment ventricular fibrillation threshold was detected, and heart weight index, left ventricular internal diameter and percentage of myocardial infarction were measured. Expression of Cx43 mRNA in myocardium was detected by real-time fluorescent quantitative polymerase chain reaction, and expression of Cx43 protein was observed by immunohistochemical method. RESULTS: Compared with the sham operation group, ventricular fibrillation threshold decreased significantly, heart weight index and left ventricular internal diameter increased, while expressions of Cx43 mRNA and protein decreased remarkably in the model group (P<0.01). Compared with the model group, ventricular fibrillation threshold was increased significantly, heart weight index, left ventricular internal diameter and percentage of myocardial infarction were decreased significantly in the YQHX group and captopril group (P<0.05 or P<0.01). When it comes to expression of Cx43, both Cx43 mRNA and protein expressions were increased remarkably in the YQHX group compared with the model group (P<0.05 or P<0.01), while only density mean and integral optical density of Cx43 protein expression were increased significantly in the captopril group (P<0.05). The enhancements on Cx43 mRNA and positive area sum of Cx43 protein induced by YQHX drugs were stronger than those induced by captopril (P<0.05). CONCLUSION: Shengmai injection and Xuesaitong injection have beneficial effects on ventricular fibrillation threshold in rats with MI. The mechanism is related with improving heart structure and reducing Cx43 expression after MI.

[Alteration of ion channel gene expression profile in rat model of post-myocardial infarction heart failure].

OBJECTIVE: To investigate the ion channel genes related with the genesis and development of heart failure after myocardial infarction through analyzing the differential gene expressions in non-infarcted myocardial tissues of post-myocardial infarction heart failure (PIHF) rat model, and that of normal rat, and the bio-informatics Stc-GO analysis on them. METHODS: Rat model of PIHF was established by left anterior descending coronary artery ligation in six SD rats, and a control group with six sham-operative rats was set. Myocardial samples were taken in two batches from them (three rats in each group) at the heart failure formation stage and the stable stage (10 days and 8 weeks after operation) respectively. Total RNA extraction, probe preparation with reverse transcription, hybridization with double-channel cDNA microarray of rat's ion channel genes, and computerized differential gene expression screening were conducted, and Stc-GO functional clustering analysis was performed on the outcomes obtained to search out the GO sort of significance in them. RESULTS: At 10 days after operation, 319 common differential expressed genes were found from the 746 target genes, all of them were up-regulated. At 8 weeks after operation, in the 276 differential expressed genes, 274 were up-regulated while the other two down-regulated. The up-regulated genes were those concerning receptors of various hormones, cytokines, neuro-hormones, growth factors and nuclear receptor, protein phosphorylase, G protein, various ion channels mediated by ligand or voltage, transport protein, receptor interfering protein, etc. The down-regulated genes concerning the potassium channel and transport protein, etc. Stc-GO analysis found that the six genes concerning adrenergic receptor kinase beta 1 (betaARK1), amiloride-sensitive cation channel 2 neuronal (Accn2), voltage-dependent calcium ion channel gamma subunit 1 (Cacng1), cyclic nucleotide gated channel alpha 1 (Cnga1), Glutamate receptor ionotropic kainite 2 (Grik 2) and neurotrophic tyrosine kinase receptor type 2 (Ntrk 2), were all the significantly up-regulated differential genes of the model group related with the sham-operative group, and all showed a down-regulating trend as time goes on, and four genes in them were validated by the RT-PCR test. CONCLUSION: Ion channel genes concerning Accn2, Grik2, Ntrk2 and Cacng1 were up-regulated in PIHF, and its mechanism is waiting for further study.

Endoplasmic reticulum stress involved in heart and liver injury in iron-loaded rats.

1. Iron overload contributes to the pathogenesis of various diseases and directly induces tissue injury. In the present study, we investigated the relationship between heart and liver injury induced by iron overload and cellular endoplasmic reticulum (ER) stress to explore the molecular mechanism of iron overload-induced cellular injury. 2. Iron overload in rats was generated by intraperitoneal injection of iron-dextran chronically (30 mg/kg per day for 9 weeks) or acutely (300 mg/kg once). Tissue injury was assessed by determining serum lactate dehydrogenase (LDH), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity, as well as malondialdehyde (MDA) content in the heart and liver. The ER stress response was analysed by expression of glucose-response protein 78 (GRP78) and activation of caspase 12. 3. In chronic iron-loaded rats, iron levels in the heart and liver were higher, by approximately 2- and 7.8-fold, respectively (P < 0.01), compared with control. Serum LDH, ALT and AST activity, as well as MDA content, GRP78 expression and caspase 12 activity in the heart and liver, were upregulated in chronically iron-loaded rats. In acute iron-loaded rats, iron content in the heart and liver was 51% and 63% higher than in controls (both P < 0.01). Serum LDH, ALT and AST activity, MDA content in the heart and liver and levels of ER stress markers were all increased in acute iron-loaded rats. N-Acetylcysteine (150 mg/kg, s.c.) lowered the levels of these parameters in acute iron-loaded rats. 4. The results of the present study indicate that ER stress may play an important role in iron-induced tissue injury and that reactive oxygen species may mediate the ER stress response in the pathogenesis of iron-overload cellular injury.

Hydrogen sulphide-induced hypothermia attenuates stress-related ulceration in rats.

1. Hydrogen sulphide (H(2)S) acts as a gaseous cellular messenger and has recently been reported to induce a suspended animation-like state in mice. The aim of the present study was to investigate the protective role of H(2)S exposure in stress gastric ulcer. 2. In the present study, we used a rat model of water immersion and restraint stress (WRS) to induce the typical stress disease, namely stress gastric ulcer. Rats were treated with WRS for 4 h, with or without pre-exposure to H(2)S (160 p.p.m. H(2)S for 2.5 h). 3. In H(2)S-exposed rats, body temperature was significantly reduced by 2.5C (P < 0.01) and oxygen consumption was reduced by 37.1% (P < 0.01) compared with control rats. Plasma levels of H(2)S were increased by 20.8% (P < 0.01) following pre-exposure. Pre-exposure to H(2)S significantly reduced the gastric ulcer index, from 24 +/- 9 to 9 +/- 2 (P < 0.01), in WRS rats. In addition, WRS increased plasma levels of adrenocorticotropin (ACTH) and corticosterone 4.7- and 4.8-fold, respectively (both P < 0.01). Pre-exposure to H(2)S markedly suppressed plasma ACTH and corticosterone level by 34.4 and 53.2%, respectively (both P < 0.01), and reduced WRS-elevated myeloperoxidase (MPO) activity by 19%. In the present study, WRS increased gastric malondialdehyde and conjugated diene content by 42 and 68%, respectively (both P < 0.01), and H(2)S exposure reduced lipid peroxide production. Finally, H(2)S exposure inhibited the WRS-elevated expression of glucose-regulated protein 78 and caspase 12, markers of endoplasmic reticulum stress. 4. In conclusion, a low concentration of H(2)S may be a new pharmacological tool for induced hypothermia to prevent severe stress-induced diseases and multifarious trauma in the clinical setting.

Endoplasmic reticulum stress response is involved in the pathogenesis of stress induced gastric lesions in rats.

Stress gastric ulcer is a serious complication, but the mechanism involved is not fully clarified. It is well known that mucosal cell apoptosis plays a crucial role in the pathogenesis of gastric ulceration. Recent studies have shown that endoplasmic reticulum (ER) stress is an important pathway leading to cellular apoptosis. To investigate the role of ER stress in the pathogenesis of stress gastric ulcer, we studied the alteration in the expression of ER stress markers GRP78 (glucose-regulated protein 78) and caspase-12 (an ER stress-specific proapoptotic molecule) and their relations with gastric mucosal apoptosis during development of stress gastric lesions in the water-immersion and restraint stress (WRS) model in rats. Rats developed severe gastric lesions after 6 h of WRS. Typical apoptosis was observed at the edge cells of WRS induced gastric lesions. Western blot analysis showed that GRP78 and activated caspase-12 were over-expressed in the gastric tissues of WRS rats. Immunohistochemical analysis demonstrated that increased GRP78 and caspase-12 were distributed only under the lesions. In addition, dithiothreitol and tunicamycin (ER stress inducers), which increased the expression of GRP78 and activated caspase-12, caused gastric mucosal injury and mucosal cell apoptosis in vitro. These findings suggest that ER stress might be involved in the development of stress gastric ulcer through an apoptotic mechanism.

Exercise training promotes expression of apelin and APJ of cardiovascular tissues in spontaneously hypertensive rats.

Because apelin may play an important regulatory role in human cardiac dysfunction, we investigated alterations in cardiovascular content of apelin and its receptor, APJ, during hypertension and the effect of exercise training on the cardiovascular apelin/APJ system in hypertensive animals. Spontaneously hypertensive rats (SHRs) underwent swimming training consisting of 54 swimming sessions of 60 min each (6 days/week for 9 weeks). Systolic blood pressure (SBP) was verified weekly by tail-cuff plethysmography. Apelin levels in plasma and cardiovascular tissues were determined by radioimmunoassay. The level of apelin/APJ mRNA was determined by RT-PCR. SHRs showed severe hypertension and pathological cardiomegaly. The level of apelin immunoreactivity (apelin-ir) in plasma and ventricular and aortic tissues was lower, by 40%, 40% and 42% (all P<0.01), respectively, in SHRs than in control Wistar-Kyoto rats, and the mRNA level of apelin and APJ in myocardium and aorta was markedly decreased. Compared with sedentary SHRs, swimming-trained SHRs showed decreased SBP and elevated mRNA expression of apelin and APJ in cardiovascular tissues and elevated apelin-ir level in plasma, myocardium and aorta (all P<0.01). SBP and level of apelin-ir in plasma and cardiovascular tissues were negatively correlated. Long-term swimming training relieved the pathogenesis of hypertension and reversed the downregulation of the cardiovascular apelin/APJ system induced by hypertension, which suggests that the improving effect of exercise training on hypertension could be mediated by upregulating the cardiovascular apelin/APJ system.