Characteristics of circular RNA expression in lung tissues from mice with hypoxia­induced pulmonary hypertension.

Pulmonary hypertension (PH) is a life­threatening lung disease, characterized by an increase in pulmonary arterial pressure caused by vasoconstriction and vascular remodeling. The pathogenesis of PH is not fully understood, and there is a lack of potential biomarkers for the diagnosis and treatment of patients with PH. Non­coding RNAs with a characteristic covalently closed loop structure, termed circular RNAs (circRNAs), are present in a number of pulmonary diseases. To the best of our knowledge, the present study is the first to use microarray analysis to determine the expression profile of circRNAs in lung tissues from mice with hypoxia­induced PH. In total, 23 significantly upregulated and 41 significantly downregulated circRNAs were identified. Of these, 12 differentially expressed circRNAs were selected for further validation using reverse transcription­quantitative polymerase chain reaction. Putative microRNAs (miRNAs) that bind to the dysregulated circRNAs were predicted. Subsequently, bioinformatics tools were used to construct circRNA­miRNA­mRNA networks for the two most promising circRNAs, namely mmu_circRNA_004592 and mmu_circRNA_018351. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses of target genes of the dysregulated circRNAs revealed that these dysregulated circRNAs may serve an important role in the pathogenesis of hypoxia­induced PH. Therefore, these dysregulated circRNAs are candidate diagnostic biomarkers and potential therapeutic targets for PH.

Icariin, a natural flavonol glycoside, extends healthspan in mice.

A major goal of aging research now is to find pharmacological manipulations in healthspan extension. Icariin is a flavonol isolated from medicinal herbal tonics. We have previously reported that icariin extended the healthspan of invertebrate models. Here, we showed that long-term treatment with icariin starting at 12months of age extended healthspan and mean lifespan in C57BL/6 mice. In all our assays associated with healthspan, such as behavioral tests and bone density analysis, we found that icariin boosted healthy features in mice. We also presented data indicating that such beneficial effects of icariin were due to at least two mechanisms: reduced oxidative stress indicated by the induction of antioxidant protein superoxide dismutase (SOD) activity and the decrease of oxidative marker malondialdehyde (MDA); maintained the genomic stability indicated by a reduction in DNA double-stranded breaks and down-regulation of DNA damage response genes. Our results indicated that icariin, a safe and widely used natural flavonol, extended healthspan and maintained genomic stability in a mammalian system.

EGb761 provides a protective effect against Aß1-42 oligomer-induced cell damage and blood-brain barrier disruption in an in vitro bEnd.3 endothelial model.

Alzheimer's disease (AD) is the most common form of senile dementia which is characterized by abnormal amyloid beta (Aß) accumulation and deposition in brain parenchyma and cerebral capillaries, and leads to blood-brain barrier (BBB) disruption. Despite great progress in understanding the etiology of AD, the underlying pathogenic mechanism of BBB damage is still unclear, and no effective treatment has been devised. The standard Ginkgo biloba extract EGb761 has been widely used as a potential cognitive enhancer for the treatment of AD. However, the cellular mechanism underlying the effect remain to be clarified. In this study, we employed an immortalized endothelial cell line (bEnd.3) and incubation of Aß(1-42) oligomer, to mimic a monolayer BBB model under conditions found in the AD brain. We investigated the effect of EGb761 on BBB and found that Aß1-42 oligomer-induced cell injury, apoptosis, and generation of intracellular reactive oxygen species (ROS), were attenuated by treatment with EGb761. Moreover, treatment of the cells with EGb761 decreased BBB permeability and increased tight junction scaffold protein levels including ZO-1, Claudin-5 and Occludin. We also found that the Aß(1-42) oligomer-induced upregulation of the receptor for advanced glycation end-products (RAGE), which mediates Aß cytotoxicity and plays an essential role in AD progression, was significantly decreased by treatment with EGb761. To our knowledge, we provide the first direct in vitro evidence of an effect of EGb761 on the brain endothelium exposed to Aß(1-42) oligomer, and on the expression of tight junction (TJ) scaffold proteins and RAGE. Our results provide a new insight into a possible mechanism of action of EGb761. This study provides a rational basis for the therapeutic application of EGb761 in the treatment of AD.

Effects of resveratrol on the expression and DNA methylation of cytokine genes in diabetic rat aortas.

This paper studies the expression of proinflammatory cytokines such as IL-1ß, IL-6, TNF-α, and IFN-γ and anti-inflammatory cytokines such as IL-10 in diabetic rat aortas, the effects of resveratrol on these cytokines, and the potential epigenetic mechanisms involved. The experiment was performed on rats divided into four groups: normal group (NC), normal interventional group (NB), diabetic group (DM), and diabetic interventional group (DB). The NB and DB groups were treated with resveratrol. After more than 3 months, the rats' aortas were removed and analyzed for cytokines by using immunohistochemistry, Western blotting, real-time PCR, and methylation-specific PCR. Histological localization of these cytokines was mainly found in the arterial intima of diabetic rats. The protein and mRNA expression levels of IL-1ß, IL-6, TNF-α, and IFN-γ were significantly higher in the DM group than in the NC group (p < 0.05), whereas in the resveratrol-treated groups (NB and DB), the levels were relatively lower than those in the corresponding groups. The DM group showed reduced levels of DNA methylation at the specific cytosine phosphate guanosine sites of IL-1ß, IL-6, TNF-α, and IFN-γ, relative to those in the NC group (p < 0.01), and these levels were increased by resveratrol. In contrast, IL-10 was dramatically methylated and showed decreased expression in response to high glucose, and resveratrol reversed this effect. These results demonstrate that the inflammatory response is involved in diabetic macroangiopathy. Resveratrol inhibits the expression of proinflammatory cytokines and thus may have a protective effect on the aorta in hyperglycemia. Thus, DNA methylation, an epigenetic gene silencing signal, may be responsible for these two phenomena.

Mechanisms Underlying the Antiproliferative and Prodifferentiative Effects of Psoralen on Adult Neural Stem Cells via DNA Microarray.

Adult neural stem cells (NSCs) persist throughout life to replace mature cells that are lost during turnover, disease, or injury. The investigation of NSC creates novel treatments for central nervous system (CNS) injuries and neurodegenerative disorders. The plasticity and reparative potential of NSC are regulated by different factors, which are critical for neurological regenerative medicine research. We investigated the effects of Psoralen, which is the mature fruit of Psoralea corylifolia L., on NSC behaviors and the underlying mechanisms. The self-renewal and proliferation of NSC were examined. We detected neuron- and/or astrocyte-specific markers using immunofluorescence and Western blotting, which could evaluate NSC differentiation. Psoralen treatment significantly inhibited neurosphere formation in a dose-dependent manner. Psoralen treatment increased the expression of the astrocyte-specific marker but decreased neuron-specific marker expression. These results suggested that Psoralen was a differentiation inducer in astrocyte. Differential gene expression following Psoralen treatment was screened using DNA microarray and confirmed by quantitative real-time PCR. Our microarray study demonstrated that Psoralen could effectively regulate the specific gene expression profile of NSC. The genes involved in the classification of cellular differentiation, proliferation, and metabolism, the transcription factors belonging to Ets family, and the hedgehog pathway may be closely related to the regulation.

H+ /K+ ATPase expression in human parietal cells and gastric acid secretion in elderly individuals.

OBJECTIVE: To investigate whether the ultrastructure and hydrogen potassium adenosine triphosphate (H+ /K+ ATPase) expression of human parietal cells were associated with aging. METHODS: In all, 50 participants who underwent gastroscopy due to dyspepsia were divided into two age groups, with 19 in the younger group (YG, aged 20-59 years) and 31 in the elder group (EG, aged ≥60 years). The ultrastructure of their parietal cell was determined by electron microscopy (EM), and the expressions of H+ /K+ ATPase α-subunit mRNA and ß-unit protein were detected. Furthermore, 24-h esophageal pH monitoring was performed in the two groups. RESULTS: EM images showed no distinct difference in the morphology and distribution of parietal cells or the acid secretion-related organelle between the two groups. There were no differences between YG and EG in the proportion of mitochondria and the tubulovesicular system area. The expressions of H+ /K+ ATPase α-subunit mRNA and ß-subunit protein showed no age-related alteration between YG and EG. The expression of H+ /K+ ATPase α-subunit mRNA in EG was higher than that in YG, whereas the expression of ß-subunit protein was significantly higher in those aged ≥80 years than in the YG. No significant difference was found in the 24-h esophageal pH monitoring between YG and EG. CONCLUSION: Acid secretion-related organelles in parietal cells do not degenerate with aging, the expression of H+ /K+ ATPase even shows a trend to increase, indicating the existence of intact molecular biological basis for acid secretion in healthy elderly individuals.

Senescent remodeling of the immune system and its contribution to the predisposition of the elderly to infections.

OBJECTIVE: To review the senescent remodeling of the immune system with aging and its relevance to the increased susceptibility of the elderly to infectious diseases, along with an outlook on emerging immunological biomarkers. DATA SOURCES: The data selected were from PubMed with relevant published articles in English or French from 1995 to the present. Searches were made using the terms "immunosenescence" and "aging" paired with the following: "innate immunity", "T-cell", "B-cell", "adaptive immunity" and "biomarkers". Articles were reviewed for additional citations and some information was gathered from web searches. STUDY SELECTION: Articles on aging of both the innate and adaptive immunity were reviewed, with special attention to the remodeling effect on the ability of the immune system to fight infectious diseases. Articles related to biomarkers of immunosenescence were selected with the goal of identifying immunological biomarkers predisposing the elderly to infections. RESULTS: Innate immunity is generally thought to be relatively well preserved or enhanced during aging compared with adaptive immunity which manifests more profound alterations. However, evidence, particularly in the last decade, reveals that both limbs of the immune system undergo profound remodeling with aging. Reported data on adaptive immunity is consistent and changes are well established but conflicting results about innate immunity were reported between in vivo and in vitro studies, as well as between murine and human studies. Epidemiological data suggests increased predisposition of the elderly to infections, but no compelling scientific evidence has directly linked senescent immune remodeling to this increased susceptibility. Recently, growing interest in identifying immunological biomarkers and defining "immune risk phenotypes/profiles" (IRP) has been expressed. Identification of biomarkers is in its early days and few potential biomarkers have been identified, with the Swedish having defined one IRP based on the adaptive immune response. CONCLUSIONS: Aging does not necessarily lead to an unavoidable decline in immune functions. Instead, a complex remodeling occurs. Despite the lack of compelling scientific evidence, senescent immune remodeling surely is a significant contributing factor to the increased risk and severity of infections in the elderly. Although, no immunological biomarker has been formally linked to the increased risk of infections in the elderly, biomarkers remain a promising tool to predict the likelihood of healthy aging, the level of immune competence, and mortality risk in the elderly. Hence, more research is required to define healthy aging and identify immunological biomarkers.

Preoperative geriatric assessment: comprehensive, multidisciplinary and proactive.

With the changing global demographic pattern, our health care systems increasingly have to deal with a greater number of elderly patients, which consequently also takes its toll on our surgical services. The elderly are not simply older adults. They represent a heterogeneous branch of the population with specific physiological, psychological, functional and social issues that require individualised attention prior to surgery. Increased acknowledgement that chronological age alone is not an exclusion criterion, along with advances in surgical and anaesthetic techniques have today lead to decreased reluctance to deny the elderly surgical treatment. In order to ensure a safe perioperative period, we believe that a comprehensive, multidisciplinary and proactive preoperative assessment will be helpful to detect the multiple risk factors and comorbidities common in older patients, to assess functional status and simultaneously allow room for early preoperative interventions and planning of the intra- and postoperative period. In this review we outline the currently available preoperative geriatric risk assessment tools and provide an insight on how a comprehensive, multidisciplinary and proactive approach can help improve perioperative outcome.

Characteristics of lymphocyte nuclear factor-κB signal transduction kinase expression in aging process and regulatory effect of epimedium flavonoids.

OBJECTIVE: To study the characteristics of lymphocyte nuclear factor kappa B (NF-κB) signal transduction kinase-related molecular mRNA differential expressions at various month age segments in aging process and the intervening effect of Epimedium flavonoids (EF) on it. METHODS: Sixty SD rats were divided into six groups, according to animals' age, i.e., the 3 days (d) group, the 4 months (m) group, the 10 m group, the 18 m group, the 27 m group, and the 27 m+EF group. RNA was extracted from separated splenic lymphocytes. Adopting NF-κB signal path functional genome oligonucleotide gene-chip (128 related genes), the integral characteristics and differences of NF-κB signal transduction kinase-related mRNA expressions were determined, and the intervening effect of EF was examined. RESULTS: The mean level of the NF-κB signal transduction kinase-related mRNA expressions in rats' splenic lymphocytes lowered with aging; the highest expression was presented at 3 d after birth, and then, it lowered gradually, with the lowest level at 18 m or 27 m. After EF intervention, the expression level was raised to the 10-18 m level in the aged rats. CONCLUSION: The changing rules of lymphocyte NF-κB-signal-transduction-kinase-related mRNA expressions in various stages of aging are helpful for selecting the well time for preventing and intervening aging, and will also give a hint to the molecular index for assessment of senility retarding researches.

[Study on changes of protein phosphorylation of p65, IkappaBalpha and IkappaBepsilon in lymphocytes of rats in progress of aging and interventional effect of Epimedium flavonoids].

OBJECTIVE: To study the characteristics of protein phosphorylation of p65, IkappaBalpha and IkappaBepsilon in lymphocytes of rats in the progress of aging and the the interventional effect of Epimedium flavonoids (EF). METHOD: We chose the lymphocytes derived from SD rat spleen. We divided the SD rats into five groups i. e. 4 months (4 m), 27 months (27 m), the 27 m EF treated group (27 m + EF), and we also observed the whole interventional effect of PDTC (a NF-kappaB inhibitor) on old rat groups (27 m PDTC, 27 m PDTC + EF ) when IkappaBepsilon, IkappaBalpha were detected. Through the western-blotting analyses, we studied the entire characteristics and distinctions of phosphorylation expression in molecules related to NF-kappaB signal transduction pathway p65, IkappaBepsilon and IkappaBalpha in lymphocytes across the age spectrum of rats in aging. We also observed the whole interventional effect of EF on lymphocytes of old rats. RESULT: With the increasing of age, the mean level of phosphorylation expressions of p65, IkappaBalpha and IkappaBepsilon in rat spleen lymphocytes decreased obviously, When inhibited NF-kappaB by PDTC, there was decreased evidently, while PDTC + EF can active NF-kappaB family and the above molecules were increased to a certain extent. CONCLUSION: The phosphorylation expressions of p65, IkappaBalpha and IkappaBepsilon in rat spleen lymphocytes were not enouphe, EF have a strong effect to upregulated the expression of them during aging.

[The effects of Ad-Gax transfection on apoptosis and related gene expression in pulmonary arterial smooth muscle cells in hypoxic rat model].

OBJECTIVE: To explore the effects of growth arrest-specific homeobox (Gax) transfection on apoptosis and expressions of Bcl-2 and Bax proteins of rat pulmonary arterial smooth muscle cells (PASMCs) exposed to hypoxia. METHODS: PASMCs were transfected with Gax gene by a replication-deficient adenovirus expressing the hemagglutinin-tagged Gax cDNA (Ad-Gax). After exposure to normal oxygenation (21% O(2)) or hypoxia (2.5% O(2)) for 2 h, 6 h, 12 h, 24 h and 48 h, apoptosis was observed by transmission electronic microscope and TUNEL-positive staining. The expressions of Bcl-2 and Bax proteins in PASMCs were detected by immunocytochemistry. RESULTS: Before Ad-Gax transfection, none or few of TUNEL-positive PASMCs were detected. After Ad-Gax transfection, the PASMCs unexposed to hypoxia displayed none or few TUNEL-positive stain, while the PASMCs exposed to hypoxia displayed a marked increase in TUNEL-positive stain, especially in cells exposed to hypoxia for 24 h to 48 h. The ratio of apoptosis of PASMCs at normoxic, hypoxia 2 h, 6 h, 12 h, 24 h and 48 h were (9.11 +/- 1.21)%, (34.13 +/- 1.02)%, (39.12 +/- 0.43)%, (50.09 +/- 0.13)%, (60.04 +/- 1.12)% and (55.47 +/- 0.03)% (P < 0.01), respectively. Before Ad-Gax transfection, the level of Bax protein showed no significant increase in PASMCs exposed to hypoxia, while that of Bcl-2 protein increased significantly, as compared to that in PASMCs under normoxic condition. The average optical density (AOD) of Bcl-2 was 2.31 +/- 0.12, 2.35 +/- 0.23, 2.49 +/- 0.27, 2.51 +/- 0.19, 2.54 +/- 0.25 and 2.53 +/- 0.20 at normoxic, hypoxia for 2 h, 6 h, 12 h, 24 h and 48 h before Ad-Gax transfection, respectively (P < 0.05, P < 0.01). After Ad-Gax transfection to PASMCs exposed to hypoxia, Bax protein increased; the AOD of Bax was 3.82 +/- 0.38, 3.12 +/- 0.42, 3.53 +/- 0.61, 4.52 +/- 0.23, 4.25 +/- 0.76 and 4.03 +/- 0.38 at normoxic, hypoxia for 2 h, 6 h, 12 h, 24 h and 48 h (P < 0.01), respectively. But Bcl-2 protein decreased significantly; the AOD of Bcl-2 was 9.11 +/- 1.21, 34.13 +/- 1.02, 39.12 +/- 0.43, 50.09 +/- 0.13, 60.04 +/- 1.12 and 55.47 +/- 0.03, respectively (P < 0.01). After Ad-Gax transfection, the Bcl-2/Bax ratio was negatively correlated with the rate of apoptotic PASMCs (r = -0.53, P < 0.01). CONCLUSION: Ad-Gax transfection induced PASMC apoptosis after exposure to hypoxia. A possible mechanism is that Gax can downregulate Bcl-2 expression and upregulate Bax expression, especially by decrease of the Bcl-2/Bax ratio.