恩格列净改善高糖诱导HK-2细胞凋亡的机制探讨

目的 探讨恩格列净改善人肾皮质近曲小管上皮细胞（HK-2细胞）凋亡的机制。方法 将HK-2细胞置于正常葡萄糖、高葡萄糖、高葡萄糖+不同浓度的恩格列净共干预环境下培养48 h。采用蛋白免疫印迹法检测肾脏沉默信息调节因子2相关酶1（SIRT1）、硫氧还蛋白互作蛋白（TXNIP）以及裂解的半胱天冬酶-3（cleaved Caspase-3）的表达水平。采用TUNEL染色评估HK-2细胞凋亡情况。结果 蛋白免疫印迹结果显示,高葡萄糖培养48 h后HK-2细胞的TXNIP和cleaved Caspase-3表达水平均高于正常葡萄糖组,而SIRT1表达水平低于正常葡萄糖组（P均< 0.05）。1000 nmol/L恩格列净和30 mmol/L葡萄糖共干预48 h后,HK-2细胞的TXNIP和cleaved Caspase-3的蛋白表达水平降低,SIRT1表达水平升高（P均< 0.001）。TUNEL染色结果显示恩格列净和30 mmol/L葡萄糖共干预组较30 mmol/L葡萄糖组TUNEL阳性细胞数少,且1000 nmol/L恩格列净和30 mmol/L葡萄糖共干预组凋亡改善更明显。结论 恩格列净可能通过上调SIRT1的表达、抑制TXNIP表达,改善高糖诱导HK-2细胞凋亡。     

A study on serum advanced glycation end products and its association with oxidative stress and paraoxonase activity in type 2 diabetic patients with vascular complications

ObjectivesEnhanced formation of advanced glycation end products (AGEs) formed secondary to hyperglycemic conditions has been linked to diabetes mellitus (DM) associated complications. We investigated the clinical relevance of estimating AGEs and their relationship with oxidative stress (OS) and paraoxonase (PON1) activity in type 2 DM (T2DM) in relation to development of vascular complications.Design and MethodsSerum AGEs along with PON1 activity, protein carbonyl (PCO), advanced oxidation protein products (AOPP), lipid peroxidation (MDA), and total thiol (T-SH) were determined in 157 T2DM patients (DM without complications n = 57, DM micro-vascular complications n = 53, DM macro-vascular complications n = 47) and 40 healthy controls.ResultsSerum AGE level increased significantly in various study groups in following manner: healthy control < DM without complications < DM-macro < DM-micro. Logistic regression analysis using diabetic complications as dependent variable showed significant association with AGE level and PON1 activity even after adjustment for confounding factors. Receiver-operating-characteristics curve analysis showed that 2-fold increased in glycation and 50% decrease in PON1 activity may lead to development of vascular complications in diabetic subjects. PCO, AOPP and MDA were higher and PON1 activity was lower in T2DM with complications than those without complications. Among diabetic patients AGEs showed significant positive correlation with HbA_1C, MDA, AOPP, and negative correlation with PON1 activity and T-SH.ConclusionHigh serum AGE concentration and low PON1 activity may be considered as additional risk factor for development of vascular complications in T2DM. AGE formation plays significant role in induction of OS in diabetes.     

Ursolic acid regulates aging process through enhancing of metabolic sensor proteins level

We previously reported that Ursolic Acid (UA) ameliorates skeletal muscle performance through satellite cells proliferation and cellular energy status. In studying the potential role of the hypothalamus in aging, we developed a strategy to pursue UA effects on the hypothalamus anti-aging proteins such as; SIRT1, SIRT6, PGC-1β and α-Klotho.In this study, we used a model of aging animals (C57BL/6). UA dissolved in Corn oil (20 mg/ml) and then administrated (200 mg/Kg i.p injection) to mice, twice daily for 7 days. After treatment times, the mice perfused and the hypothalamus isolated for preparing of tissue to Immunofluorescence microscopy.The data illustrated that UA significantly increased SIRT1 (∼3.5 ± 0.3 folds) and SIRT-6 (∼1.5 ± 0.2 folds) proteins overexpression (P< 0.001). In addition, our results showed that UA enhanced α-Klotho (∼3.3 ± 0.3) and PGC-1β (∼2.6 ± 0.2 folds) proteins levels (P < 0. 01). In this study, data were analyzed using SPSS 16 (ANOVA test).To the best of our knowledge, it seems that UA through enhancing of anti-aging biomarkers (SIRT1 and SIRT6) and PGC-1β in hypothalamus regulates aging-process and attenuates mitochondrial-related diseases. In regard to the key role of α-Klotho in aging, our data indicate that UA may be on the horizon to forestall diseases of aging.     

Neuronal apoptosis may not contribute to the long-term cognitive dysfunction induced by a brief exposure to 2% sevoflurane in developing rats

BackgroundSevoflurane is an inhaled anesthetic commonly used in the pediatric. Recent animal studies suggest that early exposure to high concentration of sevoflurane for a long duration can induce neuroapoptosis and later cognitive dysfunction. However, the neurodevelopmental impact induced by lower concentration and shorter exposure duration of sevoflurane is unclear. To investigate whether early exposure to 2% concentration of sevoflurane for a short duration (clinically relevant usage of sevoflurane) can also induce neuroapoptosis and later cognitive dysfunction.MethodsRat pups were subjected to control group, 2% sevoflurane for 3 h and 3% sevoflurane for 6 h. TUNEL assay and apoptotic enzyme cleaved caspase-3 measured by western blot were used for detection of neuronal apoptosis in frontal cortex and CA1 region of hippocampus 24 after sevoflurane treatment. Long-term cognitive function was evaluated by Morris water maze and passive avoidance test as the rats grew up.ResultsThe apoptotic levels in frontal cortex and CA1 region were significantly increased after rats exposed to 3% sevoflurane for 6 h (P < 0.05), but not 2% sevoflurane for 3 h (P > 0.05). Exposure to both 2% sevoflurane for 3 h and 3% sevoflurane for 6 h could cause long-term cognitive dysfunction and animals exposed to 3% sevoflurane for 6 h exhibited worse neurodevelopmental outcomes (P < 0.05).ConclusionIt was suggested that neuronal apoptosis might not contribute to long-term cognitive dysfunction induced by 2% concentration and short exposure time of sevoflurane. Our findings also suggested that the mechanisms of sevoflurane-induced neurodevelopmental impact might be various, depending on the concentration and exposure duration.     

Increased large VLDL and small LDL particles are related to lower bilirubin in Type 2 diabetes mellitus

ObjectivesBilirubin may protect against atherosclerotic cardiovascular disease by virtue of its anti-oxidative properties, but lower bilirubin may also be associated to atherogenic lipoprotein abnormalities. We determined associations of plasma (apo)lipoproteins and lipoprotein subfractions in subjects with and without type 2 diabetes mellitus (T2DM).Design and methodsPlasma (apo)lipoproteins, lipoprotein subfractions (nuclear magnetic resonance spectroscopy) and serum total bilirubin levels were determined in 53 T2DM patients and in 53 non-diabetic subjects.ResultsTriglycerides, large VLDL, small LDL and small HDL particles were increased (all p < 0.05), whereas HDL cholesterol, apoA-I and large HDL particles were decreased (all p < 0.05), coinciding lower bilirubin levels in T2DM (p < 0.001). In age- and sex-adjusted analysis, total cholesterol, non-HDL cholesterol, triglycerides, apoB, apoE, large VLDL and small LDL were negatively correlated with bilirubin, but HDL cholesterol was positively correlated with bilirubin in T2DM (p < 0.05 to p < 0.001). Multivariable linear regression analyses demonstrated that in all subjects combined total cholesterol, non-HDL cholesterol, triglycerides and apoE were negatively associated with bilirubin after adjustment for age, sex, T2DM, body mass index and alanine aminotransferase (all p < 0.05). Further multivariable linear regression analysis showed that large VLDL and small LDL particles were negatively associated with bilirubin, whereas large HDL particles were associated positively with bilirubin (p < 0.05).ConclusionsIncreased triglycerides, as well as large VLDL and small LDL particles are associated negatively, whereas HDL cholesterol is associated positively with bilirubin in T2DM. The proposed pro-atherogenic effects of low bilirubin could in part be attributed to relationships with abnormalities in (apo)lipoproteins and lipoprotein subfraction characteristics.     

Directional modification of chrysin for exerting apoptosis and enhancing significantly anti-cancer effects of 10-hydroxy camptothecin

Chrysin, one of natural flavonoid compounds, has recently been found to possess anti-inflammatory, antiallergic and anticancer properties. To increase its anticancer effects, 5 chrysin derivates were synthesized on the base of DNA intercalator structure. The inhibiting effects of chrysin and its derivatives on cancer cells Hela, BGC823, MCF-7, HepG2, and normal cells HEK-293, were evaluated by MTT assays. 5-(2′-amino) phenyl-7-cyclohexanemethylchrysin (Ch-1), a unique chrysin derivate, killed all the cancer cells but kept above 60% survival rate in normal cells HEK-293 at 62.5 μM. Treated with chrysin from 250 μM to 500 μM, those cells were still maintained above 60% survival rate. The result of circular dichroism spectra showed that Ch-1 could intercalate DNA while chrysin had no effects on DNA. Interestingly, Hela cells survival rates were 95% and 10%, after treated with 20 μM and 30 μM of Ch-1, respectively. Both intrinsic and extrinsic apoptotic pathway were identified in regulating the cell death caused by Ch-1 in Hela cells. p53, the upstream regulator of apoptotic pathway were extremely significantly up-regulated in Hela cells treated with 25 μM Ch-1. Moreover, the inhibiting effects and apoptotic related proteins responses to Ch-1 on Hela cells were abolished after pre-treated with Pifithrin-α (Pft-α), a p53 inhibitor. So, p53-depedent apoptosis is the crucial factor governing the inhibiting effects of Ch-1 in Hela cells. Amazingly, Ch-1 at non-toxic concentration (2.5–10 μM) enhanced significantly anti-cancer effect of 10-hydroxy camptothecin (HCPT) on Hela, BGC823, and MCF-7 cells.     

SIRT1 variants are associated with aging in a healthy Han Chinese population

BackgroundAging is influenced by diverse environmental and genetic risk factors. The SIRT1 (silent information regulator 1) gene has been shown to regulate lifespan and aging in previous studies. We determined whether variation in the SIRT1 gene is associated with aging in healthy Chinese population.MethodsThe study population comprised 482 healthy, unrelated Chinese subjects, of which 246 were aging individuals from 60 to 91 years old, and 236 younger individuals from 35 and 59 years old. All subjects were from Shenyang, China. Two single-nucleotide polymorphisms (SNP) were analyzed: rs3758391 near the 5′ end of the SIRT1 gene; and rs4746720, in the 3′ untranslated region.ResultsDifferences in allele and genotype frequency were seen between the groups, with rs3758391/C more common than rs3758391/T in the aging subjects (odds ratio = 1.453, p = 0.026), and with rs3758391/CC more common than rs3758391/CT and rs3758391/TT in the aging subjects (odds ratio = 3.042, p = 0.027). For the 3′ SNP, rs4746720/C was more common than rs4746720/T in the aging subjects (odds ratio = 1.347, p = 0.022), and rs4746720/CC was more common than rs4746720/CT and rs4746720/CT in the aging subjects (odds ratio = 1.461, p = 0.049). The haplotype frequency distribution was also different, with haplotype CC more common in the older group (odds ratio = 1.63, p = 0.01).ConclusionThese results suggest that SIRT1 gene polymorphisms may add a new factor on the multifactorial genetic contributions to aging.     

Serum 1,5-anhydroglucitol levels in patients with fulminant type 1 diabetes are lower than those in patients with type 2 diabetes

ObjectivesWe investigated clinical relevance of serum 1,5-anhydroglucitol (1,5-AG) levels in fulminant type 1 diabetes mellitus (FT1DM) patients, because 1,5-AG is known to reflect short term glycemic control.Design and methodsSubjects comprised 7 patients with FT1DM and 32 patients with type 2 diabetes mellitus (T2DM) with HbA1c < 8.5%. All of them have never been treated for diabetes.ResultsHbA_1C showed no significant difference between both groups. On the other hand, serum 1,5-AG levels were significantly lower in the FT1DM patients than in the T2DM patients. Serum 1,5-AG levels were < 5.0 μg/ml in 6 of 7 (86%) FT1DM patients, compared with only 1 of 32 (3%) T2DM patients.ConclusionsSerum 1,5-AG levels were lower in the FT1DM patients than in the T2DM patients. Serum 1,5-AG, but not HbA_1C, reflects short-term exacerbation of glycemia in patients with FT1DM.     

High glucose prevents osteogenic differentiation of mesenchymal stem cells via lncRNA AK028326/CXCL13 pathway

BackgroundHigh glucose (HG) often induces unfavorable effects on proliferation and differentiation of mesenchymal stem cells (MSCs). This study aimed to explore potential molecular pathways underlying HG functional mechanism during osteogenic differentiation of MSCs, involving lncRNA AK028326 and CXCL13.MethodsMurine bone marrow-derived MSCs were cultured in osteogenic-inducing medium supplemented with high glucose level at 25 mM or 5.5 mM as normal control. Expression levels of lncRNA AK028326 and CXCL13 were measured by using real-time PCR. The mineralized nodule formation and alkaline phosphatase (ALP) activity were detected after 21 and 7 days of incubation respectively. Western blot were also performed to determine the expression of CXCL13 and osteogenic gene markers. Plasmid pcDNAs and small interference RNAs were transfected as indicated for functional analysis of AK028326 and CXCL13.ResultsHG suppressed the expression of AK028326 and CXCL13 in MSCs in a time-dependent manner, and also the mineralization, ALP activity, and osteogenic gene expression, which could be reversed by overexpression of AK028326 or CXCL13. CXCL13 expression was positively regulated by AK028326 at both mRNA and protein levels. Moreover, CXCL13 mediated the positive regulation of AK028326 on osteogenic gene expression in MSCs and MC3T3-E1 cells, mineralization and ALP activity in MSCs and also HG-induced inhibitory effects during MSCs differentiation into osteoblast.ConclusionHG could inhibit osteogenic differentiation of MSCs via inhibited expression of CXCL13 mediated by lncRNA AK028326, thereby providing new insights into the molecular mechanism of many osteogenesis-related diseases especially for patients with hyperglycemia.     

Antiproliferation and induction of caspase-8-dependent mitochondria-mediated apoptosis by β-tocotrienol in human lung and brain cancer cell lines

The pure vitamin isomer, β-tocotrienol has the least abundance among the other vitamin E isomers that are present in numerous plants. Hence, it is very scarcely studied for its bioactivity. In this study, the antiproliferative effects and primary apoptotic mechanisms of β-tocotrienol on human lung adenocarcinoma A549 and glioblastoma U87MG cells were investigated. It was evidenced that β-tocotrienol had inhibited the growth of both A549 (GI₅₀ = 1.38 ± 0.334 μM) and U87MG (GI₅₀ = 2.53 ± 0.604 μM) cells at rather low concentrations. Cancer cells incubated with β-tocotrienol were also found to exhibit hallmarks of apoptotic morphologies including membrane blebbing, chromatin condensation and formation of apoptotic bodies. The apoptotic properties of β-tocotrienol in both A549 and U87MG cells were the results of its capability to induce significant (P < 0.05) double-strand DNA breaks (DSBs) without involving single-strand DNA breaks (SSBs). β-Tocotrienol is said to induce activation of caspase-8 in both A549 and U87MG cells guided by no activation when caspase-8 inhibitor, z-IETD-fmk was added. Besides, disruption on the mitochondrial membrane permeability of the cells in a concentration- and time-dependent manner had occurred. The induction of apoptosis by β-tocotrienol in A549 and U87MG cells was confirmed to involve both the death-receptor mediated and mitochondria-dependent apoptotic pathways. These findings could potentiate the palm oil derived β-tocotrienol to serve as a new anticancer agent for treating human lung and brain cancers.     

Study on the mechanism of HIF1a-SOX9 in glucose-induced cardiomyocyte hypertrophy

A major cause of morbidity and mortality in cardiovascular disease is pathological cardiac hypertrophy. With an increase in the cellular surface area and upregulation of the atrial natriuretic peptide (ANP) gene, cardiac hypertrophy is a prominent feature of diabetic cardiomyopathy. ANP is a hypertrophic marker. Many works have been done to explore how the glucose induces the cardiac hypertrophy. However, it is not enough for us to figure it out. In this study, the influences of different glucose concentrations on cardiomyocytes were examined in vitro. The results showed that cardiomyocytes cultured with 25 mM glucose tended to show a hypertrophic phenotype, while cardiomyocytes cultured with 35 mM glucose tended to undergo apoptosis. An increased expression of SOX9 was observed when cardiomyocytes were cultured with 25 mM glucose, but when the concentration of glucose was increased to 35 mM, the expression of SOX9 decreased. We used the RNAi approach to knockdown SOX9 expression, to assess its effects on cardiomyocyte hypertrophy. The results showed that knockdown of the SOX9 gene suppressed the 25 mM glucose-induced cardiomyocyte hypertrophy. The upregulation of the ANP gene was associated with overexpression of SOX9. Additionally, the results showed that high glucose (HG, 25 mM) treatment increased the expression of hypoxia-inducible factor (HIF)1a. Further study showed that HIF1a participated in regulating SOX9 expression in response to HG. This study revealed a novel regulatory mechanism of HIF1a-SOX9 in high glucose-induced cardiomyocyte hypertrophy, as well as the related molecular mechanisms.     

Lactobacillus rhamnosus induced epithelial cell apoptosis,ameliorates inflammation and prevents colon cancer development in an animal model

Background/AimProbiotics have been suggested as prophylactic measure in colon carcinogenesis. This study aimed at determining the potential prophylactic activity of Lactobacillus rhamnosus GG CGMCC 1.2134 (LGG) strain on colorectal carcinogenesis via measuring its effect on Nuclear factor kappa B (NFκB) inflammatory pathway and apoptosis.Materials and methods64 Sprague Dawley rats were grouped into four as follows; Group 1 (Healthy control), Group 2 (LGG), Group 3 (cancer control Dimethyl hydrazine (DMH)) and Group 4 (LGG + DMH). LGG was administered orally to LGG and LGG + DMH groups. Colon carcinogenesis was chemically induced in LGG + DMH and DMH groups by weekly injection of 40 mg/kg DMH. Animals were sacrificed after 25 weeks of experiment and tumor characteristics assessed. The change in expression of NFκB-p65, COX-2, TNFα, Bcl-2, Bax, iNOS, VEGFα, β-catenin, Casp3 and p53 were evaluated by western blotting and qRT-PCR.ResultsLGG treatment significantly reduced tumor incidence, multiplicity and volume in LGG + DMH treatment group compared to DMH cancer control group. Also, LGG treatment reduced the expression of β-catenin and the inflammatory proteins NFκB-p65, COX-2 and TNFα; the anti-apoptotic protein Bcl-2, but increased the expression of the pro-apoptotic proteins Bax, casp3 and p53 compared with DMH group.ConclusionLGG have a potential protection effect against colon carcinogenesis; inducing apoptosis and ameliorating inflammation, and may hold a promise as bio-therapeutic dietary agent.     

Apple pectin: A natural source for cancer suppression in 4T1 breast cancer cells in vitro and express p53 in mouse bearing 4T1 cancer tumors,in vivo

PurposeIncrease in the number of cancer related deaths has made the study on developing new drugs and treatments essential. One of the main aims in developing new therapies is to use natural resources which have the ability to induce apoptosis. Pectin is one of these natural compounds, a complex polysaccharide found in apples with anti-cancer properties. The aim of this study was to examine anti-cancer properties of pectic acid both in vitro in 4T1 breast cancer cells and in vivo using an animal model of breast cancer.Experimental designMTT cell proliferation assays, double fluorescence staining (acridine orange/ethidium bromide) and cell cycle analysis were employed to measure apoptosis in vitro. 4T1 cells were implanted into female BALB/c mice for in vivo studies. Then tumor volumes, histological analysis and immunohistochemical staining of P53 and tunnel test were applied to evaluate apoptosis in tumors.ResultsThe results of in vitro studies showed that concentration of 0.1% of pectic acid could induce apoptosis, inhibit cell growth (p < 0.001) and reduce cell attachment, fragmented chromatin, and membrane blebbing as well as blocking the sub-G1 phase (p < 0.001). In addition, in vivo studies showed that pectic acid could inhibit the progression of tumors through over-expression of P53 and increasing the number of apoptotic cells.ConclusionOur results demonstrated that pectic acid, a natural component of apple, can prevent metastasis in both cancer cell lines and primary tumors. This potential effect is mainly due to its ability to induce apoptosis.     

Correlations of creatine and six related pyrimidine metabolites and diabetic nephropathy in Chinese type 2 diabetic patients

ObjectivesThe assessment of the clinical significance of creatine, cytosine, cytidine, uridine, thymine, thymidine, and 2′-deoxyuridine concentrations in patients with type 2 diabetes mellitus (T2DM) and diabetic nephropathy (DN) for the detection of the relationship between pyrimidine metabolites and disease.Design and methodsThe study group consisted of 119 subjects, which were divided to three groups: control (n = 31), type 2 diabetes without nephropathy (DM, n = 23), and with nephropathy (DN, n = 65). Levels of related metabolites were measured in plasma of all participants.ResultsThere is a significant increase in levels of cytosine (P < 0.001), cytidine (P < 0.001), and thymidine (P = 0.016) with DN compared to DM. The levels of uridine, thymine, 2′-deoxyuridine, and creatine did not change.ConclusionsThe levels of cytosine, cytidine, and thymidine may be useful for monitoring the progression of DM and evaluating the treatment.     

Impact of mulberry leaf extract on type 2 diabetes (Mul-DM): A randomized,placebo-controlled pilot study

AimsMulberry leaves have been used anecdotally in Asia to treat many disease states, including glucose abnormalities. Animal and human studies illustrate potential benefit of mulberry leaf extract (MLE) in type 2 diabetes mellitus (DM2). The purpose of this study is to evaluate the glycemic and safety effects of MLE in patients with DM2.Materials & methodsThis randomized, double-blind, placebo-controlled pilot study evaluated MLE (1000 mg standardized) versus matching placebo given three times daily with meals. Patients (n = 24) were included if they had DM2 on single or combination oral therapy with a stable hemoglobin A1C (A1C). A 2-week placebo run-in (baseline) was followed by initiation of randomized medication for 3 months. Primary endpoints were change in A1C and self-monitoring blood glucoses (SMBG). Safety was also evaluated.ResultsOf 24 patients enrolled, 17 patients completed the study. Post-prandial SMBG was significantly decreased at 3 months in the MLE group versus baseline (16.1%; p < 0.05). This improvement in post-prandial SMBG persisted when compared to placebo (18.2%; p < 0.05). A1C decreased from 7.30% at baseline to 6.94% in the MLE group but did not reach statistical significance (p = 0.079). There was no difference in A1C between MLE and placebo. A significant 15% increase occurred in serum creatinine when the MLE group was compared to baseline or placebo (p < 0.05 for both). There was no significant effect on weight, fasting SMBG, blood pressure, hypoglycemia, or other safety evaluation markers.ConclusionsThese results suggest that mulberry leaf extract may be a useful complementary mealtime glucose option for patients with DM2.ClinicalTrials.gov Identifier NCT00795704.     

Association of vascular indices with novel circulating biomarkers as prognostic factors for cardiovascular complications in patients with type 2 diabetes mellitus

BackgroundThe pathophysiology of atherosclerosis in type 2 diabetes mellitus (T2DM) is multifactorial. The association of vascular indices with circulating biomarkers of inflammation and insulin resistance and their role in the long-term cardiovascular prognosis in T2DM patients were currently investigated.Patients and methodsPatients with T2DM and poor glycemic control without known cardiovascular diseases (n = 119) at baseline were enrolled and followed for about 9 years. The end-point was the occurrence of any cardiovascular event (coronary heart disease, stroke, peripheral artery disease or cardiovascular death). Aortic pulse wave velocity (PWV), augmentation index (AIx), brachial flow-mediated dilation (FMD), hsCRP, Chitinase-3-like protein 1 (YKL-40), Neutrophil Gelatinase-Associated Lipocalin (NGAL), Fatty Acid Binding Protein (FABP-4) were assessed.ResultsHigher YKL-40 and NGAL were associated with higher PWV, while higher YKL-40 and FABP-4 were related to higher AIx (p < 0.05 for all). In univariate Cox regression analysis, PWV > 10 m/s, YKL-40 > 78 ng/ml and NGAL > 42 ng/ml were associated with cardiovascular events (p < 0.05 for all). In multivariate analysis, after adjusting for classical risk factors and glycemic control, increased NGAL, YKL-40 and PWV and decreased FMD (i.e. ≤ 2.2%) (p < 0.05 for all) were independently associated with cardiovascular events.ConclusionIn T2DM patients without established cardiovascular disease, novel indices of vascular inflammation (NGAL and YKL-40) were associated with subclinical atherosclerosis (arterial stiffness) but also with adverse clinical prognosis. Arterial stiffness and endothelial dysfunction were also independently related to adverse prognosis.     

Puerarin protects human umbilical vein endothelial cells against high glucose-induced apoptosis by upregulating heme oxygenase-1 and inhibiting calpain activation

The aim of this study was to investigate whether puerarin protects against high glucose (HG)-induced apoptosis by suppressing calpain activation in human umbilical vein endothelial cells (HUVECs). HUVECs were exposed to normal glucose (NG) (5.5 mm) or HG (33 mm) for 48 h; then, apoptosis and caspase-3 activity were determined. The expression of heme oxygenase-1 (HO-1) mRNA was evaluated by RT-PCR analysis. The activation of calpain and HO activity were also assessed. Compared with the NG group, exposure of HUVECs to HG for 48 h resulted in significant increases in calpain and caspase-3 activity as well as apoptosis, which were prevented by co-incubation with puerarin (1-100 μm) in a concentration-dependent manner. HO-1 mRNA expression and HO activity were decreased in HUVECs treated with HG for 48 h. Compared with the group exposed to HG alone, co-incubation of HUVECs with puerarin and HG induced increases in HO-1 mRNA expression and HO activity. The HO-1 inhibitor protoporphyrin IX zinc (II) abolished the inhibitory effect of puerarin on HG-induced calpain and caspase-3 activation, as well as apoptosis. The data show that puerarin protects against HG-induced endothelial cell apoptosis by a mechanism involving upregulation of HO-1 expression and inhibition of calpain activity.     

Urinary matrix metalloproteinase-8 and -9 activities in type 2 diabetic subjects: A marker of incipient diabetic nephropathy?

Matrix metalloproteinases (MMPs) may play a pathophysiological role in the development of diabetic nephropathy (DN). We hypothesized that urinary MMP activity in patients with type 2 diabetes mellitus (T2DM) is related to a decline in renal function. We determined MMP-2, -8 and -9 activity in 24-h urine collections in relation to risk factors for DN in T2DM patients with (UA, n = 27) and without albuminuria (NA, n = 48) and controls (CO, n = 28). MMP-8 and -9 levels were highest in UA patients (P < 0.01). Of UA patients, 93% had at least one MMP increased, compared to 78% of NA patients and 46% of CO (P = 0.001). Age, diabetes duration, BMI, systolic blood pressure, fasting plasma glucose, HbA1c and renal function were determinants of MMP-8 and -9 (P < 0.05). In summary, MMP-8 and -9 are highest in T2DM UA patients. MMP-9, showed the strongest associations with clinical parameters related to DN.