Dihydroartemisinin eliminates senescent cells by promoting autophagy-dependent ferroptosis via AMPK/mTOR signaling pathway.

Cellular senescence is an irreversible cell-cycle arrest in response to a variety of cellular stresses, which contribute to the pathogenesis of a variety of age-related degenerative diseases. However, effective antisenescence strategies are still lacking. Drugs that selectively target senescent cells represent an intriguing therapeutic strategy to delay aging and age-related diseases. Thus, we thought to investigate the effects of dihydroartemisinin (DHA) on senescent cells and elucidated its mechanisms underlying aging. Stress-induced premature senescence (SIPS) model was built in NIH3T3 cells using H2O2 and evaluated by ß-galactosidase staining. Cells were exposed to DHA and subjected to cellular activity assays including viability, ferroptosis, and autophagy. The number of microtubule-associated protein light-chain 3 puncta was detected by immunofluorescence staining. The iron content was assessed by spectrophotometer and intracellular reactive oxygen species (ROS) was measured by fluorescent probe dichlorodihydrofluorescein diacetate. We found that DHA triggered senescent cell death via ferroptosis. DHA accelerated ferritin degradation via promoting autophagy, increasing the iron contents, promoting ROS accumulation, thus leading to ferroptotic cell death in SIPS cells. In addition, autophagy inhibitor BafA1 preconditioning inhibited ferroptosis induced by DHA. Moreover, Atg5 silencing and autophagy inhibitor BafA1 preconditioning inhibited ferroptosis induced by DHA. We also revealed that the expression of p-AMP-activated protein kinase (AMPK) and p-mammalian target of rapamycin (mTOR) in senescent cells was downregulated. These results suggested that DHA may be a promising drug candidate for clearing senescent cells by inducing autophagy-dependent ferroptosis via AMPK/mTOR signaling pathway.

Cordycepin inhibits cell senescence by ameliorating lysosomal dysfunction and inducing autophagy through the AMPK and mTOR-p70S6K pathway.

Cell senescence is closely related to autophagy. In this article, we identified a natural nucleoside analogue, cordycepin, that has the ability to significantly improve lysosomal function, enhance the activity of the lysosomal representative protease cathepsin B (CTSB), and promote the expression of the functional protein lysosomal-associated membrane protein 2 (LAMP2) on the lysosomal membrane. Cordycepin then restores the damaged autophagy level of aging cells by activating the classic AMPK and mTOR-p70S6K signaling pathways, thus inhibiting cell senescence in an H2 O2 -induced stress-induced premature senescence (SIPS) cell model. This study provides new theoretical support for the further development of cordycepin and clinical antiaging drugs to inhibit cell senescence and suggests that the regulatory mechanisms of lysosomes in senescent cells should be considered when treating age-related diseases.

PAX6 contributes to the activation and proliferation of hepatic stellate cells via activating Hedgehog/GLI1 pathway.

Aberrant activation of Hedgehog signaling is considered as the key player in hepatic stellate cell (HSC) activation involved in liver fibrosis (LF). The glioma-associated protein gene (GLI) has a predicted paired box 6 (PAX6)-binding site within its transcribed region. Therefore, this study aimed to investigate the relationship between PAX6 and GLI and their contribution to HSC activation and proliferation. PAX6 expression was upregulated in platelet-derived growth factor-BB (PDGF-BB)-induced LX-2 cells. The activation and proliferation of HSC were inhibited by interference of PAX6 with short hairpin RNA (shPAX6) via curbing Hedgehog signaling. Notably, PAX6 directly bound to the promoter sequence of GLI1 independent of the PTCH/SMO axis. Therefore, we propose that PAX6 upregulation induces HSC activation and proliferation through crosstalk with GLI1 signaling. Thus, these novel mechanistic insights involving the PAX6-mediated regulation of the activation and proliferation of HSC may provide a new therapeutic target for LF.

Autophagy inhibition via Becn1 downregulation improves the mesenchymal stem cells antifibrotic potential in experimental liver fibrosis.

Liver fibrosis (LF) is the result of a vicious cycle between inflammation-induced chronic hepatocyte injury and persistent activation of hepatic stellate cells (HSCs). Mesenchymal stem cell (MSC)-based therapy may represent a potential remedy for treatment of LF. However, the fate of transplanted MSCs in LF remains largely unknown. In the present study, the fate and antifibrotic effect of MSCs were explored in a LF model induced by CCl4 in mouse. Additionally, MSCs were stimulated in vitro with LF-associated factors, tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), and transforming growth factor-ß1 (TGF-ß1), to mimic the LF microenvironment. We unveiled that MSCs exhibited autophagy in response to the LF microenvironment through Becn1 upregulation both in vivo and in vitro. However, autophagy suppression induced by Becn1 knockdown in MSCs resulted in enhanced antifibrotic effects on LF. The improved antifibrotic potential of MSCs may be attributable to their inhibitory effects on T lymphocyte infiltration, HSCs proliferation, as well as production of TNF-α, IFN-γ, and TGF-ß1, which may be partially mediated by elevated paracrine secretion of PTGS2/PGE2 . Thus, autophagy manipulation in MSCs may be a novel strategy to promote their antifibrotic efficacy.

[Establishing Glioma-associated Oncogene Homolog 1 Genetic Lineage-tracing Mice for Studies on Hepatic Fibrosis].

OBJECTIVE: To establish Gli1-CreERt2; tdTomato genetic lineage-tracing mice for studies on hepatic fibrosis. METHODS: Offspring of ROSA26 td Tomato (tdTomato) mice and Gli1-CreERt2 mice (Gli1 mice) were obtained, with Gli1-CreERt2; tdTomato genotype being identified by PCR. The mice model of hepatic fibrosis was induced with CCl4. Their liver samples were taken. The formalin-fixed and paraffin-embedded samples were prepared for HE staining and Masson staining. The expression of tdTomato was observed under immunofluorescent microscope. RESULTS: An ideal number of Gli1-CreERt2; tdTomato genetic lineage-tracing mice were harvested. The differences in fertility between the parental and the offspring mice were not significant (P>0.05). Pseudolobular formation occurred in the CCl4-induced hepatic fibrosis model mice. Enhanced red fluoresce was observed in the model mice. CONCLUSION: Gli1-CreERt2; tdTomato genetic lineage-tracing mice can be used to monitor the cell source of fibrous tissues, its transition as well as the underlying mechanism of pathogenesis of hepatic fibrosis.

Unexpected role of the human cytomegalovirus contribute to essential hypertension in the Kazakh Chinese population of Xinjiang.

Human cytomegalovirus (HCMV) infection, chronic inflammation and oxidative stress, the renin-angiotensin system (RAS), endothelial function, and DNA methylation play roles in the pathogenesis of essential hypertension (EH); however, the mechanism by which HCMV predisposes patients to hypertension remain unclear. Our group previously demonstrated an association between EH and HCMV infection in Kazakh Chinese. Here, we investigated the relationship between HCMV infection and other clinicopathological features in 720 Kazakh individuals with or without hypertension (n=360 each; age: 18-80). Multiple linear and logistic regression analyses were used to determine the associations between HCMV infection, clinical characteristics, and EH. Notably, patients with EH, particularly those with HCMV infection, exhibited a marked increase in tumor necrosis factor-α (TNF-α) and 8-hydroxy-2-deoxyguanosine (8-OHDG) levels, but a decrease in endothelial nitric oxide synthase (eNOS) and renin levels. Similarly, elevated TNF-α and 8-OHDG levels were independent predictors of increased HCMV antibody titers, whereas eNOS and renin were negatively correlated with the latter. Moreover, serum angiotensin-converting enzyme (sACE, ACE) methylation was increased, whereas 11-ß hydroxysteroid dehydrogenase 2 (HSD11ß2; HSD3B2) methylation was decreased in patients with EH who were also infected with HCMV. A positive correlation between HSD3B2 methylation and HCMV IgG titer and blood pressure was additionally observed, whereas angiotensin-converting enzyme (ACE) methylation was inversely correlated with blood pressure. Collectively, these data indicate that HCMV may contribute to EH development in the Kazakh Chinese by increasing TNF-α and 8-OHDG levels, suppressing eNOS and renin, and manipulating HSD3B2 and ACE methylation.

Differentiation of rat adipose-derived mesenchymal stem cells into corneal-like epithelial cells driven by PAX6.

Corneal integrity, transparency and vision acuity are maintained by corneal epithelial cells (CECs), which are continuously renewed by corneal limbal stem cells (LSCs). Deficiency of CECs and/or LSCs is associated with numerous ocular diseases. Paired box (PAX)6 is an eye development-associated transcription factor that is necessary for cell fate determination and differentiation of LSCs and CECs. In the present study, the PAX6 gene was introduced into adipose-derived rat mesenchymal stem cells (ADMSCs) to investigate whether PAX6-transfected cells were able to transdifferentiate into corneal-like epithelial cells and to further verify whether the cells were suitable as a cell source for corneal transplantation. The ADMSCs were isolated from the bilateral inguinal region of healthy Sprague Dawley rats. The characteristics of ADMSCs were identified using flow cytometric analysis. After subculture, ADMSCs underwent transfection with recombinant plasmid containing either PAX6-enhanced green fluorescent protein (EGFP) complementary (c)DNA or EGFP cDNA (blank plasmid group), followed by selection with G418 and determination of the transfection efficiency. Subsequently, the morphology of the ADMSCs and the expression profiles of corneal-specific markers CK3/12 and epithelial-specific adhesion protein were determined. E-cadherin was detected using immunofluorescence staining and western blot analysis at 21 days following transfection. An MTT cell proliferation and a colony formation assay were performed to assess the proliferative activity and clonogenicity of PAX6-transfected ADMSCs. Finally, the PAX6-expressing ADMSCs were transplanted onto the cornea of a rabbits with limbal stem cell deficiency (LSCD). At 21 days after transfection, the ADMSCs with PAX6 transfection exhibited a characteristic flagstone-like appearance with assembled corneal-like epithelial cells, and concomitant prominent expression of the corneal-specific markers cytokeratin 3/12 and E-cadherin. Furthermore, the proliferation and colony formation ability of PAX6-overexpressing ADMSCs was significantly retarded. The transplantation experiment indicated that PAX6-reprogramed ADMSCs attached to and replenished the damaged cornea via formation of stratified corneal epithelium. Taken together, these results suggested that conversion of ADMSCs into corneal-like epithelium may be driven by PAX6 transfection, which makes ADMSCs a promising cell candidate for the treatment of LSCD.

Association between high cytomegalovirus antibody titers and blood pressure in the adult Kazakh and Han Chinese populations.

BACKGROUND: Human cytomegalovirus (CMV) has been linked to the pathogenesis of elevated arterial blood pressure (BP). Our study aimed to determine the association between anti-CMV titers and arterial BP in the Kazakh and Han Chinese populations. MATERIAL AND METHODS: Kazakh and Han (n = 800 each) (age, ≥18 years) subjects from Xinjiang, China were examined for anti-CMV immunoglobulin (Ig)G titers using a commercially available enzyme-linked immunosorbent assay (ELISA) kit. The highest anti-CMV titer tertiles determined within gender and ethnicity groups were compared against the two lower tertiles and seronegative samples. RESULTS: Multivariate linear regression analysis revealed that anti-CMV titers were independent determinants for elevated systolic (p = 0.006) BP in Kazakh women and inversely associated with systolic (p = 0.004) and mean arterial (p = 0.019) BP in Han women. CONCLUSION: The association between CMV infection and/or resulting immune response and BP elevation differed by sex and ethnicity. In Kazakh women, they were associated with elevated BP and the opposite was true among Han women.

Mesenchymal stem cell-mediated suppression of hypertrophic scarring is p53 dependent in a rabbit ear model.

INTRODUCTION: Mesenchymal stem cells (MSCs) are considered to play important roles in wound repair and tissue remodeling. Hypertrophic scar (HTS) is a cutaneous condition characterized by deposits of excessive amount of collagen after an acute skin injury. However, currently there is little knowledge about the direct relationship between MSCs and HTS. METHODS: The hypertrophic scar model was established on rabbit ears. MSCs were isolated from rabbit femur bone marrow and transplanted through ear artery injection. Hypertrophic scar formation was examined using frozen-section analysis, hematoxylin and eosin (HE) staining, Masson's trichrome staining, and scar elevation index. The role of p53 in the MSCs-mediated anti-scarring effect was examined by gene knockdown using p53 shRNA. RESULTS: In this study, MSCs engraftment through ear artery injection significantly inhibited the hypertrophic scarring in a rabbit ear hypertrophic scar model, while this anti-scarring function could be abrogated by p53 gene knockdown in MSCs. Additionally, we found that MSCs down-regulated the expression of TGF-ß receptor I (TßRI) and alpha-smooth muscle actin (α-SMA) at both mRNA and protein levels in a paracrine manner, and this down-regulation was rescued by p53 gene knockdown. Moreover, our results showed that MSCs with p53 gene knockdown promoted the proliferation of fibroblasts through increasing nitric oxide (NO) production. CONCLUSIONS: These results suggest that MSCs inhibit the formation of HTS in a p53 dependent manner through at least two mechanisms: inhibition of the transformation of HTS fibroblast to myofibroblast; and inhibition of the proliferation of fibroblasts through inhibition of NO production.

Human cytomegalovirus infection is associated with essential hypertension in Kazakh and Han Chinese populations.

BACKGROUND: We aimed to study the association between cytomegalovirus (CMV) infection and hypertension in Kazakh and Han populations from Xinjiang Province, China. MATERIAL/METHODS: We analyzed data on 800 Kazakhs (467 hypertension patients and 333 healthy control participants) and 800 Hans (482 hypertension patients and 318 healthy control participants) aged 18-84 years old. ELISA and real-time quantitative PCR coupled with restriction fragment length polymorphism analysis were applied for determining CMV infection and glycoprotein B (gB) genotypes, respectively. RESULTS: Serologic evidence of CMV infection was obtained for 95.4% and 90.1% of the Kazakhs and Hans, respectively. The CMV seroprevalence rates among the Kazakh and Han participants with hypertension were 96.8% and 89.8%, respectively. Multiple logistic regression analyses revealed statistically significant independent associations between CMV seropositivity and hypertension in Kazakh males and between CMV antibody titers and hypertension in Hans; significant relationships also existed between CMV antibody titers and blood pressure in Hans. In Kazakhs, 3 CMV gB genotypes were identified: gB2 and genotype mixtures gB1+gB2 and gB2+gB3. In Hans, 4 CMV gB genotypes were identified: gB1, gB2, gB1+gB2, and gB2+gB3. Of the 4 studied genotypes, gB2+gB3 showed a significant independent association with hypertension in Kazakh females. CONCLUSIONS: CMV infection is associated with essential hypertension in Kazakh males and Hans in Xinjiang. CMV seropositivity is associated with hypertension in Kazakh males, and CMV antibody titers are associated with blood pressure and hypertension in Han males and females. Moreover, the CMV gB2+gB3 genotype mixture is associated independently with essential hypertension in Kazakh females.

Association of genetic polymorphisms in HSD17B1, HSD17B2 and SHBG genes with hepatocellular carcinoma risk.

Genetic polymorphisms of enzymes involved in estrogen synthesizing/transporting can influence the risk of hormone-dependent diseases. The incidence rate and relative risk for hepatocellular carcinoma (HCC) are higher in men than in women. This study was conducted to explore the relationship of single nucleotide polymorphisms (SNPs) in 17 ß-Hydroxysteroid dehydrogenases (HSD17B1 and HSD17B2) and sex hormone-binding globulin (SHBG) genes with the risk of HCC within Chinese Han population. Polymorphisms of HSD17B1 rs676387, HSD17B2 rs8191246 and SHBG rs6259 were genotyped in 253 HCC patients and 438 healthy control subjects using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Significantly increased HCC risk was found to be associated with T allele of rs676387 and G allele of rs8191246. Increased HCC risks were found in different genetic model (TT genotype in a recessive model, T allele carriers in a dominant model, TT genotype and TG genotype in a codominant model for HSD17B1 rs676387, G allele carriers in a dominant model and AG genotype in a codominant model for HSD17B2 rs8191246, respectively). No association between SHBG rs6259 and HCC risk was observed. The present study provided evidence that HSD17B1 rs676387 and HSD17B2 rs8191246 were association with HCC development. Further studies in diverse ethnic population with larger sample size were recommended to confirm the findings.

Effect of pomegranate peel polyphenol gel on cutaneous wound healing in alloxan-induced diabetic rats.

BACKGROUND: Pomegranate (punica granatum) belongs to the family Punicaceae, and its peel has been used as a traditional Chinese medicine because of its efficacy in restraining intestine, promoting hemostasis, and killing parasites. Pomegranate peel has been reported to possess wound-healing properties which are mainly attributed to its polyphenol extracts. The purpose of this study was to investigate the effect of pomegranate peel polyphenols (PPP) gel on cutaneous wound healing in diabetic rats. METHODS: Alloxan-induced diabetic rats were given incisional wounds on each side of the mid-back and then treated daily with PPP gel (polyphenol mass fraction = 30%) post-wounding. Rats were sacrificed on days 4, 7, 14, and 21 post-wounding to assess the rates of wound closure, histological characteristics; and to detect the contents of hydroxyproline, production of nitric oxide (NO), and activities of NO synthase (NOS), as well as the expressions of transforming growth factor-ß1 (TGF-ß1), vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF) in wound tissue. RESULTS: Wound closure was significantly shortened when PPP gel was applied to the wounds of diabetic rats. Histological examination showed the ability of PPP gel to increase fibroblast infiltration, collagen regeneration, vascularization, and epithelialization in the wound area of diabetic rats. In addition, PPP gel-treated diabetic rats showed increased contents of hydroxyproline, production of NO, and activities of NOS and increased expressions of TGF-ß1, VEGF, and EGF in wound tissues. CONCLUSION: PPP gel may be a beneficial method for treating wound disorders associated with diabetes.

[Extracellular Ca(2+)-sensing receptor-induced extracellular Ca2+ influx is down-regulated by caveolin-1 in human umbilical vein endothelial cells].

Although the function of extracellular Ca(2+)-sensing receptor (CaR) is known, the regulatory mechanism of the CaR function remains to be clarified. The purpose of the present study was to investigate the effect of caveolin-1 (Cav-1) on CaR-induced extracellular Ca(2+) influx by using acute caveolae disruption with Filipin or siRNA targeted to the Cav-1 in human umbilical vein endothelial cells (HUVECs). Intracellular Ca(2+) concentration ([Ca(2+)](i)) was detected by Fura-2/AM loading. The results showed that different concentrations of extracellular Ca(2+) failed to increase [Ca(2+)](i), while the CaR agonist Spermine (2 mmol/L) resulted in an increase in [Ca(2+)](i) that was diminished in buffer without Ca(2+) (P<0.05). No matter in buffer with or without 2 mmol/L Ca(2+), the [Ca(2+)](i) increase induced by Spermine in HUVECs was abolished after inhibition of CaR by a negative allosteric modulator Calhex231 (1 µmol/L) (P<0.05), conversely, the effect of Spermine on the increase in [Ca(2+)](i) in HUVECs was further augmented after acute caveolae disruption with Filipin (1.5 µg/mL) or transfection with siRNA targeted to the Cav-1 (P<0.05). This indicated that Cav-1 produced an inhibition of CaR-induced extracellular Ca(2+) influx. As to the biological mechanism of Cav-1-induced inhibition, immunofluorescence technique showed that both CaR and Cav-1 were present in HUVECs, and confocal microscopy supported the co-localization of CaR and Cav-1 on the plasma membrane. Functionally, the Cav-1 protein expression was decreased in HUVECs transfected with siRNA targeted to the Cav-1 (P<0.05); simultaneously, the CaR membrane protein expression was decreased (P<0.05), whereas CaR total protein level was unaffected (P>0.05). In conclusion, the present study suggests that CaR and Cav-1 co-localize on the plasma membrane in HUVECs and CaR-induced Ca(2+) influx is down-regulated by binding with Cav-1, and the mechanism involves the effect of Cav-1 on CaR localization on the plasma membrane and attenuating the CaR response to the agonist.

[Association of the tagging single nucleotide polymorphisms in transforming growth factor beta-1 gene with hypertension in the Han nationality population in Xinjiang].

OBJECTIVE: Essential hypertension (EH) was a complex disease resulted from the interaction of cumulative effect of multiple genetic and environment factors. The relationship between the genetic polymorphisms in the transforming growth factor-beta1 (TGF-beta1), the blood levels and EH have been investigated, but the conclusions were different. Therefore, we investigate the relationship between the tagging single nucleotide polymorphisms (tSNPs) (rs1800469, rs2241716, rs11466345, rs2241715, rs4803455) in TGF-beta1 gene, blood levels and EH in the Han nationality population in Xinjiang, to clarity the pattern of linkage disequilibrium (LD) and the feature of the structure of haplotype. METHODS: Based on the case-control study,we selected 732 (365 EH patients,367 controls) Han Chinese population from the Boertonggu countryside of Shawan region in the Xinjiang Uygur Autonomous Region of China by random cluster sampling. After questionnaire and physical examination, we collected blood samples, and the blood levels of TGF-beta1 were quantified using sandwich ELISA. The polymorphisms of TGF-beta1 gene in the study groups were detected with SNaPshot system. The case-control study in a large group was carried out separately for each of the tSNP and followed up by haplotypes analyses to determine the relation between tSNPs of TGF-beta1 gene and EH in the Han population. RESULTS: (1) The frequencies of alleles A, G of rs11466345 of TGF-beta1 gene in EH group and control group were as follows: 69.7%, 30.3%, 74.4%, 25.6%, respectively. It was demonstrated that the G allele of the rs11466345 polymorphism occurred at a significantly higher frequency in EH patients than in healthy controls (30.3% vs. 25.6%, P < 0.05). The rs11466345G-allele carriers had a significantly increased risk of EH compared to rs11466345A-allele carrier (OR = 1.261; P < 0.05). The frequencies of genotypes and alleles of the other tSNPs of TGF-beta1 gene had no difference between EH patients and controls (P > 0.05). (2)Except the site of rs11466345, the other tSNPs were in strong LD, and no statistical differences were observed in haplotypes distribution in the followup study between case-control groups (P > 0.05). (3) There were no difference of TGF-beta1 levels between the different genotypes and alleles in tSNPs of TGF-beta1 gene (P > 0.05). CONCLUSIONS: (1) These results suggested that TGF-beta1 gene rs11466345 G allele was likely to be a genetic susceptibility factor for EH in the Xinjiang Han population, the other tSNPs perhaps had no association with EH of in the study groups. (2) Except rs11466345, the other tSNPs were in strong LD, and the haplotypes reconstructed by tSNPs might not be associated with EH in the Han nationality populations. (3) There was no association between the tSNP of TGF-beta1 gene and TGF-beta1 blood levels in the Xinjiang Han nationality population.

[Association of the TGF-beta1 gene polymorphisms and blood TGF-beta 1 level with essential hypertension in Kazakh Chinese].

OBJECTIVE: To investigate the association of the transforming growth factor- beta 1 (TGF- beta 1) gene polymorphisms and blood TGF- beta 1 level with essential hypertension (EH) in Kazakh Chinese. METHODS: The polymorphisms of TGF- beta 1 gene in 354 Kazakh EH patients and 435 healthy controls were detected with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing. The blood level of TGF- beta 1 was quantified using specific sandwich ELISA. RESULTS: The frequencies of genotypes GG, GC and alleles G and C of +915G/C in Xinjiang Kazakh were 97.9%, 2.1% and 98.77%, 1.23%, respectively. No significantly difference was found between EH patients and controls (P>0.05). The frequencies of genotypes TT, TC, CC and alleles T and C of +869T/C in controls was 25.97%, 46.67%, 27.36%, 49.3% and 50.7%, respectively, the CC genotype or C allele in EH patients had significantly higher frequencies than controls [41.60% vs. 27.36%, and 62.2% vs. 50.7%, respectively (P<0.05)]. It was also shown that TGF- beta 1 +869 C allele carriers had significantly increased risk of EH compared with T allele carriers (OR=1.60, P=0.00). There was linkage disequilibrium (LD) between the two polymorphisms. The frequency of haplotype C-G in the EH group was significantly higher than that in controls (61.6% vs. 49.8%, P<0.05). There were no differences in TGF- beta 1 level among different genotypes or alleles in both +869T/C and +915G/C loci (P>0.05). CONCLUSION: The frequency of +915G/C variation of the TGF- beta 1 gene was very low in Kazakh and there was no homozygous variation. The +869 C allele was likely the genetic susceptibility factor for EH in the population. There was linkage disequilibrium in the polymorphisms of +869T/C and +915G/C. Haplotype C-G was the risk factor of EH.

[Interaction between TGF-beta1/Smad pathway and ERK pathway in vascular smooth muscle cells].

OBJECTIVE: To investigate if the interaction between TGF-beta1/Smad pathway and ERK pathway in vascular smooth muscle cells exists. METHODS: The rat arota was removed. The primary VSMC were isolated and cultured in vitro, then the VSMC were divided into four groups: (1) control group, (2) (TGF-beta1 group, (3) ERK blocking agent group, (4) TGF-beta1 + ERK blocking agent group. The expression of Smad2/3, ERK1/2 proteins, the content of phosphorylated ERK1/2 and Smad2/3 proteins were detected by Western blot, and the expression of Smad2/3 mRNA was detected by reverse transcription-polymerase chain reaction(RT-PCR) . RESULTS: (1) In contrast to control group, the content of phosphorylated Smad2/3 and phosphorylated ERK1/2 proteins in TGF-beta1 group was increased (P < 0.05), that in ERK blocking agent group was decreased (P < 0.05). There was no difference between control group and TGF-beta1 + ERK blocking agent group. Compared with TGF-beta1 group, the contents of phosphorylated Smad2/3 and phosphorylated ERK1/2 proteins in TGF-beta1 + ERK blocking agent group was decreased (P < 0.05). There was no difference in the expression of Smad2/3 and ERK1/2 proteins among different groups. (2) There were no differences in expression of Smad2 and Smad3 mRNA among different groups. CONCLUSION: (1) TGF-beta1 can induce Smad2/3 proteins to be phosphorylated dependent on the activated ERK pathway. (2) ERK pathway does not effect the expression of Smad2/3 at the level of protein and mRNA.

Mitochondrial DNA haplogroups in a Chinese Uygur population and their potential association with longevity.

1. The haplogroups and polymorphisms of mitochondrial (mt) DNA are associated with longevity. This association is highly geographically dependent. The aim of the present study was to determine the relationship between mtDNA haplogroups, single nucleotide polymorphisms (SNPs) and longevity in the Chinese Uygur population. 2. Ninety-eight Uygur Chinese subjects aged over 90 years (vitality 90+) and 117 healthy young controls living in the Xinjiang Uygur Autonomous Region of China were chosen for the present study. Frequencies of mtDNA haplogroups and SNPs in the subjects were analysed using polymerase chain reaction. The entire mtDNA genome was sequenced and the mtDNA haplogroups and SNPs were determined. 3. Nine haplogroups were identified in the Chinese Uygur population and the frequency of haplogroup J was higher in control subjects than in the vitality 90+ group (odds ratio = 0.384; 95% confidence interval = 0.163-0.906; P = 0.025). Interestingly, most of the SNPs were in the D-loop region, with frequencies higher in the control group than in the vitality 90+ group. 4. In conclusion, mtDNA haplogroups are potentially associated with longevity in the Uygur Chinese population and the D-loop region is strongly involved in ageing-related events.

[Relationship between lung injury induced by hemorrhagic shock/reperfusion and nitric oxide and beneficial effect of taurine].

AIM: To approach the relationship between lung injury induced by shock/reperfusion and nitric oxide as well as the beneficial effect of taurine. METHODS: Twenty four rabbits were divided randomly into 3 groups (n = 8): control group, shock group, taurine group. The model of lung injury induced by shock/reperfusion was used. The activities of nitric oxide synthase (NOS), superoxide dismutase (SOD), the contents of malondialdehyde (MDA), nitric oxide products (NO2-/NO3-) in plasma and lung homogenate, lung wet/dry weight, lung water content, lung permeability index, and protein content in the pulmonary alveolar lavage fluid were measured. Meanwhile, pathologic samples treated routinely. RESULTS: (1) At 3 hours after reperfusion, the activities of SOD in plasma and lung homogenate decreased markedly, but the other indexes above mentioned were increased significantly compared with the control group (P < 0.01). (2) A close correlation was shown between MDA content and NO2-/NO3- content in plasma and lung. Furthermore, the content of NO2-/NQ3- in lung homogenate showed strong positive correlation with the lung injury parameters. (3) Taurine (40 mg x kg(-1) i.v.) could attenuate all the changes above mentioned at the same time points of reperfusion. CONCLUSION: NO may play an important role in lung injury induced by shock/reperfusion. Taurine can ameliorate the lung injury, mechanism of which may be related to decreasing the generation of NO and anti-lipoperoxidation.

[Effects of taurine on NOS activity in myocardium and plasma of hemorrhagic shock resuscitation in rabbits].

AIM: To investigate the effect of taurine on nitric oxide synthase (NOS) activity and nitric oxide products (NO2 /NO3 ) content in myocardium and plasma during shock resuscitation. METHODS: Twenty-four rabbits were divided randomly into 3 groups (n=8): control group, shock group, taurine group. The model of hemorrhagic shock resuscitation was used. The activities of nitric oxide synthase (NOS), lactate dehydrogenase (LDH) and the contents of nitric oxide products (NO2- /NO3-) in plasma were observed before shock and shock 1.5 hours, after resuscitation 1 hour, 2 hours and 3 hours. The activities of NOS and the contents of NO2-/NO3- in myocardium homogenate were measured after resuscitation 3 hours. Meanwhile, pathologic samples treated routinely. RESULTS: (1) During resuscitation, the activities of NOS, LDH and the contents of NO2- /NO3- in plasma of shock group were significantly higher than that of before shock and shock 1.5 hours (P < 0.01). (2) After resuscitation 3 hours, the activity of NOS and the contents of NO2- / NO3 in myocardium of shock group were significantly higher than that of control group (P < 0.01). The cardiac myocyte appeared edema, fatty degeneration. (3) All the changes of above mentioned could be attenuated by intravenous injection taurine (40 mg/kg) (P < 0.01). CONCLUSION: These results suggest that the NOS activation and NO release may mediated myocardium injury induced by shock resuscitation, taurine can ameliorate the myocardium injury, which may be related to decreasing the generation of NO.