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A high-glucose environment is involved in the progression of diabetes mellitus (DM). This study aims to explore the regulatory effects of quercetin (QUE) on autophagy and apoptosis after myocardial injury in rats with DM. The type 2 DM rat models were constructed using low-dose streptozotocin (STZ) treatment combined with a high-carbohydrate (HC) diet in vivo. Compared with the control group, the body weight was decreased, whereas blood pressure, blood glucose, and the LVW/BW ratio were increased in the diabetic group. The results showed that the myocardial fibers were disordered in the diabetic group. Moreover, we found that the myocardial collagen fibers, PAS-positive cells, and apoptosis were increased, whereas the mitochondrial structure was destroyed and autophagic vacuoles were significantly reduced in the diabetic group compared with the control group. The expression levels of autophagy-related proteins LC3 and Beclin1 were decreased, whereas the expression levels of P62, Caspae-3, and Bax/Bcl-2 were increased in the diabetic group in vitro and in vivo. Moreover, QUE treatment alleviated the cellular oxidative stress reaction under high-glucose environments. The results of immunoprecipitation (IP) showed that the autophagy protein Beclin1 was bound to Bcl-2, and the binding capacity increased in the HG group, whereas it decreased after QUE treatment, suggesting that QUE inhibited the binding capacity between Beclin1 and Bcl-2, thus leading to the preservation of Beclin1-induced autophagy. In addition, the blood pressure, blood glucose, and cardiac function of rats were improved following QUE treatment. In conclusion, QUE suppressed diabetic myocardial injury and ameliorated cardiac function by regulating myocardial autophagy and inhibition of apoptosis in diabetes through the AMPK/mTOR signaling pathway. [ABSTRACT FROM AUTHOR]

Objective: To detect the levels of interleukin-33 (IL-33) and soluble ST2 (sST2) in peripheral blood of patients with essential hypertensive left ventricular hypertrophy, and to discusstheir correlation with patients with essential hypertensive left ventricular hypertrophy was further discussed. Methods: A total of 220 patients with essential hypertension treated in the Department of Cardiovascular Medicine of the First Affiliated Hospital of Bengbu Medical College were enrolled as the experimental group. According to left ventricular mass index LVMI), patients with essential hypertension were divided into the non-left ventricular hypertrophy group (NLVH, n=108 cases) and the left ventricular hypertrophy group (LVH, n=112 cases). We used ELISA to detect the serum levels of IL-33 and sST2, the expression levels of IL-33 in peripheral blood lymphocytes of the NLVH group and the LVH group (60 cases each) were detected by Western blot, and the relationship between IL-33 and LVMI, a marker of left ventricular hypertrophic condition, was analyzed by Pearson. The relationship between IL-33, sST2 and left ventricular hypertrophy in essential hypertension was studied. Results: Compared with the NLVH group, the expression levels of IL-33 and sST2 in the LVH group were significantly increased. The results of Western blot showed that the expression level of IL-33 in the LVH group (1.07±0.08) was higher than that in the NLVH group (0.63±0.05) (P<0.05). Pearson correlation analysis showed that IL-33 was positively correlated with LVMI, sST2 was positively correlated with LVMI. Conclusion: The levels of IL-33 and sST2 in serum and the expression levels of IL-33 protein in peripheral blood lymphocytes are significantly increased in patients with hypertensive left ventricular hypertrophy, and the occurrence and development of essential hypertensive left ventricular hypertrophy may be related to IL-33 and sST2. [ABSTRACT FROM AUTHOR]

Few studies have compared the clinical manifestations of patients with premature acute coronary syndrome (ACS) and late-onset ACS as well as the adverse cardiovascular events following percutaneous coronary intervention (PCI). To investigate the clinicopathological characteristics of patients with premature ACS and adverse cardiovascular events following PCI, a total of 726 patients with ACS undergoing PCI were divided into two groups: A premature ACS group and a late-onset ACS group. Following discharge, all patients were followed-up for an average of 23.5±5.3 months. Clinical characteristics, Gensini scores, vascular lesions and adverse cardiovascular events were compared between the two groups. There were no significant differences in smoking, diabetes, ACS composition ratio, baseline treatment of coronary heart disease, high-density lipoprotein level and C-reactive protein levels between the two groups. Sex and hypertriglyceridemia were determined to be independent risk factors of premature ACS, while age, hypertension and a high Gensini score were independent risk factors for adverse cardiovascular events in patients with ACS following PCI. Furthermore, the prevalence of premature ACS was significantly higher in females. Although serum levels of fasting blood glucose, total cholesterol, triglycerides and low-density lipoprotein were also significantly higher in patients with premature ACS compared with patients with late-onset ACS, patients with premature ACS exhibited fewer vascular lesions compared with patients with late-onset ACS. Furthermore, the incidence of adverse cardiovascular events in patients with ACS following PCI did not differ significantly between premature and late-onset ACS groups. Taken together, these results suggest that female patients should be closely observed for early risk factors of premature ACS to prevent and reduce the occurrence of adverse cardiovascular events in patients with ACS following PCI. [ABSTRACT FROM AUTHOR]

MicroRNA (miR)-138 serves an important role in the proliferation, differentiation and apoptosis of human pulmonary artery smooth muscle cells (HPASMCs), indicating the involvement of miR-138 in the development and progression of pulmonary artery hypertension (PAH). Potassium channel subfamily K member 3 (TASK-1), a two-pore domain K+ channel, is expressed in HPASMCs and is associated with hypoxic PAH. However, whether miR-138 mediates PAH through targeting TASK-1 is not known. In the present study, HPASMCs were transfected with miR-138 mimic to establish a PAH model in vitro, and the effects of a miR-138 inhibitor and a TASK-1 inhibitor (A293) were examined. Cell proliferation and mitochondrial membrane potential (MMP) were measured by CCK-8 assay and flow cytometry, respectively. Reverse transcription-quantitative polymerase chain reaction and western blotting were performed to examine the expression of miR-138, TASK-1, Bcl-2, caspase-3 and activation of extracellular signal-regulated kinase 1/2 (ERK1/2). A dual-luciferase reporter assay was also used to analyse the expression level of TASK-1 in HPASMCs. The results of the present study demonstrated that the miR-138 mimic promoted proliferation and MMP level, which was similar to the effect of A293 treatment on HPASMCs. However, the miR-138 inhibitor inhibited the effects induced by miR-138 mimic or A293 treatment, as demonstrated by a decrease in proliferation and MMP level in HPASMCs, accompanied by a decrease of Bcl-2 and an increase of caspase-3 expression levels, as well as ERK1/2 activation. The dual-luciferase reporter assay indicated that TASK-1 expression was negatively regulated by miR-138. The results of the present study suggested that miR-138 promoted proliferation and suppressed mitochondrial depolarization of HPASMCs by targeting TASK-1. [ABSTRACT FROM AUTHOR]

Purpose:Type I collagen is one of the most abundant components of extracellular matrix. We previously illustrated that murine fibrosarcoma L929 cells grew well on type I collagen gel and escaped from TNFα-induced cell death. In this study, we investigated the mechanism underlying the protective effect of collagen gel.Material and methods:We used western blot, confocal microscopy, MTT assay and flow cytometry by introducing fluorescence staining to determine the expression levels of nuclear factor kappa B (NF-κB), inhibitory ratio and autophagy.Results:L929 cells on collagen gel showed higher expression of NF-κB in the nucleus. Inhibition of NF-κB with pyrrolidine dithiocarbamate hydrochloride (PDTC) or knockdown by NF-κB-siRNA canceled the protective effect of collagen gel on L929 cells from TNFα-induced death, suggesting for the role of NF-κB in the protection from cell death. We found a new aspect of the effect of PDTC on L929 cells cultured on collagen gel. PDTC alone without TNFα induced apoptosis in the L929 cells cultured on collagen gel but not the cells on plastic dish. The apoptosis induction of the L929 cells cultured on collagen gel with PDTC was repressed by inhibiting autophagy with chloroquine, an autophagy inhibitor, suggesting that autophagy contributes to the death induced by the treatment with PDTC. Possible underlying mechanism of this finding is discussed.Conclusion:NF-κB played an important role in protecting the L929 cells cultured on collagen gel from TNFα-induced death. [ABSTRACT FROM AUTHOR]

In the present study, we examined the morphological features of the adrenal gland in Bactrian camel by means of digital anatomy, light and electron microscopy. Our findings testified that the gland was divided into three parts, capsule, cortex and medulla from outside to inside as other mammals, and the cortex itself was further distinguished into four zones: zona glomerulosa, zona intermedia, zona fasciculate and zona reticularis. Notably, the zona intermedia could be seen clearly in the glands from females and castrated males, whereas it was not morphologically clear in male. There was a great deal of lipid droplets in the zona fasciculate, while it was fewer in the zona glomerulosa and zona reticularis. The cytoplasm of adrenocortical cell contained rich mitochondria and endoplasmic reticulum. The adrenal medulla was well-developed with two separations of external and internal zones. The most obvious histological property of adrenal medulla cells were that they contained a huge number of electron-dense granules enveloped by the membrane, and so medulla cells could be divided into norepinephrine cells and epinephrine cells. Moreover, the cortical cuffs were frequently present in adrenal gland. Results of this study provides a theoretical basis necessary for ongoing investigations on Bactrian camels and their good adaptability in arid and semi-arid circumstances. [ABSTRACT FROM AUTHOR]

Purpose: Gelatin has been considered to exist as intermediate substance of collagen catabolism in tissue remodeling or under inflammatory conditions. We have initiated the study on possible biological functions of gelatin that can exist temporally and locally under the conditions of remodeling and inflammationMaterials and methods: To this purpose, we investigated cell proliferation and survival on gelatin-coated dishes and the response to tumor necrosis factor α (TNFα)–induced cytotoxicity in L929 cells. Autophagy level, ATP level, and ROS generation are examined.Results: L929 cells detached from the gelatin-coated dishes and formed multicellular aggregates. TNFα-induced cytotoxicity in L929 cells was inhibited by gelatin-coating culture. The cells on gelatin-coated dishes showed reduced cellular ATP levels and increased adenosine 5′-monophosphate (AMP)–activated protein kinase (AMPK) phosphorylation, leading to increased ROS generation and autophagy.Conclusion: This study showed that gelatin-coated culture protected L929 cells from TNFα-induced cytotoxicity and suggested for a possible pathophysiological function of gelatin in regulating cellular functions. [ABSTRACT FROM PUBLISHER]

Murine fibrosarcoma L929 cells have been used to test efficacy of proinflammatory cytokine TNFα. In the present study, we reported on protective effect of type I collagen gel used as L929 cell culture. L929 cell grew and proliferated well on collagen gel. However, the L929 cells exhibited cobblestone-like morphology which was much different from the spread fusiform shape when cultured on conventional cell dishes as well as the cells tended to aggregate. On conventional cell culture dishes, the cells treated with TNFα became round in shape and eventually died in a necroptotic manner. The cells cultured on collagen gel, however, were completely unaffected. TNFα treatment was reported to induce autophagy in L929 cells on the plastic dish, and therefore we investigated the effect of collagen gel on induction of autophagy. The results indicated that autophagy induced by TNFα treatment was much reduced when the cells were cultured on collagen gel. In conclusion, type I collagen gel protected L929 cell from TNFα-induced cell death. [ABSTRACT FROM AUTHOR]

Highlights: [•] With the development of diabetes in rat, ventricular function was aggravated. [•] Cardiac ALDH2 expression was decreased with the development of diabetes in rat. [•] Ethanol which was used as a tool to induce ALDH2 activity decreased myocardial injury in diabetes rat. [ABSTRACT FROM AUTHOR]

The previous studies suggested that some subpopulations of T lymphocytes against central nervous system (CNS) antigens, such as myelin basic protein (MBP), are neuroprotective. But there were few reports about the effect of these T cells on axon regeneration. In this study, the neonatally thymectomied (Tx) adult rats which contain few T lymphocytes were subjected to spinal cord hemisection and then passively immunized with MBP-activated T cells (MBP-T). The regeneration and dieback of transected axons of cortico-spinal tract (CST) were detected by biotin dextran amine (BDA) tracing. The behavioral assessments were performed using the Basso, Beattie, and Bresnahan locomotor rating scale. We found that passive transferring of MBP-T could attenuate axonal dieback. However, no significant axon regeneration and behavioral differences were observed among the normal, Tx and sham-Tx (sTx) rats with or without MBP-T passive immunization. These results indicate that passive transferring of MBP-T cells can attenuate axonal dieback and promote neuroprotection following spinal cord injury (SCI), but may not promote axon regeneration. [ABSTRACT FROM AUTHOR]

Aim:To investigate the role of nitric oxide (NO) in oridonin-induced apoptosis and autophagy in murine fibrosarcoma L929 cells and the underlying molecular mechanisms.Methods:Cell viability was measured using MTT assay. Intracellular NO level, SubG1 cell ratio and autophagy cell ratios were analyzed with flow cytometry after diaminofluorescein-2 diacetate (DAF-2DA), propidium iodide (PI) and monodansylcadaverine (MDC) staining, respectively. Protein expression was examined using Western blot analysis.Results:Exposure of L929 cells to oridonin (50 μmol/L) for 24 h led to intracellular NO production. Pretreatment with NOS inhibitor 1400w or L-NAME inhibited oridonin-induced apoptosis and autophagy in L929 cells. The pretreatment decreased the apoptosis-related protein Bax translocation and cytochrome c release, increased Bcl-2 level, reversed the autophagy-associated protein Beclin 1 increase and conversion of LC3 I to LC3 II. Furthermore, pretreatment with NO scavenger DTT completely inhibited oridonin-induced apoptosis and autophagy in L929 cells. In addition, oridonin (50 μmol/L) activated ERK and p53 in L929 cells, and the interruption of ERK and p53 activation by PD 98059, pifithrin-α, or ERK siRNA decreased oridonin-induced apoptosis and autophagy. The inhibition of NO production reduced oridonin-induced ERK and p53 activation, and NO production was down-regulated by blocking ERK and p53 activation.Conclusion:NO played a pivotal role in oridonin-induced apoptosis and autophagy in L929 cells. Taken together with our previous finding that ERK contributes to p53 activation, it appears that NO, ERK, and p53 form a positive feedback loop. Consequently, we suggest that oridonin-induced apoptosis and autophagy are modulated by the NO-ERK-p53 molecular signaling mechanism in L929 cells. [ABSTRACT FROM AUTHOR]

To observe the changes of lung injury when diabetic rats were treated with low concentration of ethanol (EtOH) and analyze the related mechanisms, male Sprague-Dawley (SD) rats were divided into control, diabetic (DM), and EtOH+DM groups. Diabetic rat was mimicked by injection of streptozotocin intraperitoneally. Fasting blood glucose (FBG) level, lung weight (LW), body weight (BW), and LW/BW were measured. The changes of lung tissue and Type II alveolar cell were detected. Pulmonary malondialdehyde (MDA) content and superoxide dismutase (SOD) activity were measured; meanwhile, ALDH2 mRNA and protein expressions were detected by RT-PCR and western blotting, respectively. Compared with control group, in DM group, SOD activity was decreased; FBG level, LW/BW, MDA content, ALDH2 mRNA, and protein expressions were decreased. Compared with DM group, in EtOH+DM group, SOD activity, ALDH2 mRNA, and protein expressions were increased; LW/BW and MDA content were decreased. The structures of lung tissue and lamellar bodies were collapsed in DM group; the injury was attenuated in EtOH+DM group. Our findings suggested that, in diabetic rat, pulmonary ALDH2 expression was decreased accompanying lung injury. EtOH at low concentration decreased diabetes induced lung injury through activating ALDH2 expression.

The aim of the present study was to determine the changes in mitochondrial aldehyde dehydrogenase 2 (ALDH2) activity in relation to oxidative stress and inflammatory injury in different stages of diabetes mellitus (DM) in rats and to investigate the related mechanisms. DM in Sprague-Dawley (SD) rats was induced by a single intraperitoneal injection of 55 mg/kg streptozotocin (STZ). The rats were randomly allocated into a control group, as well as into DM4w, DM8w and DM12w groups containing DM rats 4, 8 and 12 weeks after DM induction, respectively. Ventricular hemodynamic parameters were recorded; fasting blood glucose (FBG) and glycosylated hemoglobin (HbA1c) levels were determined using an automatic biochemistry analyzer; plasma interleukin (IL)-1, IL-4 and cardiac 4-hydroxynon-2-enal (4-HNE) levels were determined using enzyme-linked immunosorbent assay (ELISA), and cardiac ALDH2 activity was measured. The mRNA expression levels of Bax and Bcl-2 of the left anterior myocardium were detected by reverse transcriptase‑polymerase chain reaction (RT-PCR). FBG and HbA1c levels were increased in the DM groups compared to the control group. FBG levels were not significantly different among the DM4w, DM8w and DM12w groups, while HbA1c levels were increased with the progression of diabetes. The left ventricular developed pressure (LVDP), heart rate (HR) and rate-pressure product (RPP) were decreased, plasma IL-1 levels were increased, while IL-4 levels were decreased in the DM groups compared to the control group. Additionally, cardiac 4-HNE levels were increased, and ALDH2 activity was decreased in the DM groups compared to the control group. Bax mRNA levels were increased, Bcl-2 mRNA levels were decreased, and Bcl-2/Bax mRNA ratios were decreased in the DM groups compared to the control group. Moreover, LVDP, HR, RPP, IL-4, ALDH2 activity and Bcl-2/Bax mRNA ratios were further reduced, while 4-HNE and IL-1 levels were increased with the progression of diabetes. In conclusion, our results indicated that cardiac ALDH2 activity was further decreased with the progression of diabetes, which might be related to the increase of oxidative stress, inflammatory injury and the occurrence of apoptosis.

The aim of this study was to investigate the role of mitofusin-2 (Mfn2) in different stages of diabetes in rats and to analyze the related mechanism(s). A diabetic model in SD rats was induced by a single intraperitoneal injection of 55 mg/kg streptozoticin (STZ). The hearts were isolated from diabetes mellitus (DM) rats at the fourth week (DM4W), eighth week (DM8W) and twelfth week (DM12W) and fasting blood glucose (FBG) levels and the ratio of heart weight to body weight (HW/BW) were measured. Malondialdehyde (MDA) content, superoxide dismutase (SOD) and caspase 3 activities were measured. The expression of Mfn2 of the left anterior myocardium at the mRNA level was detected using RT‑PCR. In contrast to the normal group, in the DM4W, DM8W and DM12W groups, there was a significant increase in the FBG levels, but no difference among the DM4W, DM8W and DM12W groups. The HW/BW ratio as well as the MDA content were increased, while SOD activity was reduced. Caspase‑3 activity was increased, while the expression of Mfn-2 mRNA levels was reduced. In addition, with the development of diabetic cardiomyopathy, the contents of MDA and caspase 3 were increased, whereas SOD activity and Mfn-2 mRNA levels were further reduced. In conclusion, our results indicated that with the development of diabetes, the expression of cardiac Mfn2 has showed a decrease, which may be associated with the decrease of antioxidant ability and progression of apoptosis.