BACKGROUND Excessive reactive oxygen species generated in mitochondria has been implicated as a causal event in hypertensive cardiomyopathy. Multiple recent studies suggest that microRNAs (miRNAs) are able to translocate to mitochondria to modulate mitochondrial activities, but the medical significance of such a new miRNA function has remained unclear. Here, we characterized spontaneous hypertensive rats (SHRs) in comparison with Wistar rats, finding that micro RNA-21 (miR-21) was dramatically induced in SHRs relative to Wistar rats. We designed a series of experiments to determine whether miR-21 is involved in regulating reactive oxygen species generation in mitochondria, and if so, how induced miR-21 may either contribute to hypertensive cardiomyopathy or represent a compensatory response. METHODS Western blotting was used to compare the expression of key nuclear genome (nDNA)–encoded and mitochondrial genome (mtDNA)–encoded genes involved in reactive oxygen species production in SHRs and Wistar rats. Bioinformatics was used to predict miRNA targets followed by biochemical validation using quantitative real-time polymerase chain reaction and Ago2 immunoprecipitation. The direct role of miRNA in mitochondria was determined by GW182 dependence, which is required for miRNA to function in the cytoplasm, but not in mitochondria. Recombinant adeno-associated virus (type 9) was used to deliver miRNA mimic to rats via tail vein, and blood pressure was monitored with a photoelectric tail-cuff system. Cardiac structure and functions were assessed by echocardiography and catheter manometer system. RESULTS We observed a marked reduction of mtDNA-encoded cytochrome b (mt-Cytb) in the heart of SHRs. Downregulation of mt-Cytb by small interfering RNA in mitochondria recapitulates some key disease features, including elevated reactive oxygen species production. Computational prediction coupled with biochemical analysis revealed that miR-21 directly targeted mt-Cytb to positively modulate mt-Cytb translation in mitochondria. Circulating miR-21 levels in hypertensive patients were significantly higher than those in controls, showing a positive correlation between miR-21 expression and blood pressure. Remarkably, recombinant adeno-associated virus–mediated delivery of miR-21 was sufficient to reduce blood pressure and attenuate cardiac hypertrophy in SHRs. CONCLUSIONS Our findings reveal a positive function of miR-21 in mitochondrial translation, which is sufficient to reduce blood pressure and alleviate cardiac hypertrophy in SHRs. This observation indicates that induced miR-21 is part of the compensatory program and suggests a novel theoretical ground for developing miRNA-based therapeutics against hypertension.

BackgroundRecent studies have emphasized causative links between microRNAs (miRNAs) deregulation and tumor development. In hepatocellular carcinoma (HCC), more and more miRNAs were identified as diagnostic and prognostic cancer biomarkers, as well as additional therapeutic tools. This study aimed to investigate the functional significance and regulatory mechanism of the miR-199a2/214 cluster in HCC progression.Methods and FindingsIn this study, we showed that miR-214, as well as miR-199a-3p and miR-199a-5p levels were significantly reduced in the majority of examined 23 HCC tissues and HepG2 and SMMC-7721 cell lines, compared with their nontumor counterparts. To further explore the role of miR-214 in hepatocarcinogenesis, we disclosed that the ER stress-induced pro-survival factor XBP-1 is a target of miR-214 by using western blot assay and luciferase reporter assay. Re-expression of miR-214 in HCC cell lines (HepG2 and SMMC-7721) inhibited proliferation and induced apoptosis. Furthermore, ectopic expression of miR-214 dramatically suppressed the ability of HCC cells to form colonies in vitro and to develop tumors in a subcutaneous xenotransplantation model of the BALB/c athymic nude mice. Moreover, reintroduction of XBP-1s attenuated miR-214-mediated suppression of HCC cells proliferation, colony and tumor formation. To further understand the mechanism of the miR-199a/214 cluster down-expression in HCC, we found that thapsigargin (TG) and tunicamycin (TM) or hypoxia-induced unfolded protein response (UPR) suppresses the expression of the miR-199a/214 cluster in HCC cells. By promoter analysis of the miR-199a2/214 gene, we conjectured NFκB as a potential negative regulator. We further found that UPR and LPS-induced NFκB activation suppressed miR-199a2/214 transcription, and this suppression was reversed by NFκB inhibition in HCC cells.ConclusionsOur study suggest that modulation of miR-214 levels may provide a new therapeutic approach for cancer treatment and revealed that UPR may offer a new explanation for why the miR-199a/214 cluster were down-regulated in the progression in HCC.

We implement a unique strategy for single molecule counting termed stochastic labeling, where random attachment of a diverse set of labels converts a population of identical DNA molecules into a population of distinct DNA molecules suitable for threshold detection. The conceptual framework for stochastic labeling is developed and experimentally demonstrated by determining the absolute and relative number of selected genes after stochastically labeling approximately 360,000 different fragments of the human genome. The approach does not require the physical separation of molecules and takes advantage of highly parallel methods such as microarray and sequencing technologies to simultaneously count absolute numbers of multiple targets. Stochastic labeling should be particularly useful for determining the absolute numbers of RNA or DNA molecules in single cells.etermining small numbers of biological molecules and their changes is essential when unraveling mechanisms of cellular response, differentiation or signal transduction, and in performing a wide variety of clinical measurements. Although many analytical methods have been developed to measure the relative abundance of different molecules through sampling (e.g., microarrays and sequencing), the only practical method available to determine the absolute number of molecules in a sample is digital PCR (1-3), a powerful analytical technique typically limited to examining only a few different molecules at a time.In 2003, a theoretical approach to measure the number of molecules of a single mRNA species in a complex mRNA preparation was proposed (4). To our knowledge no experimental demonstration of this idea has been published. We have generalized this idea and have expanded it to a highly parallel method capable of absolute counting of many different molecules simultaneously. The concept is illustrated in Fig. 1. Each copy of a molecule randomly captures a label by choosing from a large, nondepleting reservoir of diverse labels. The subsequent diversity of the labeled molecules is governed by the statistics of random choice, and depends on the number of copies of identical molecules in the collection compared to the number of kinds of labels. Once the molecules are labeled, they can be amplified so that simple present/absent threshold detection methods can be used for each. Counting the number of distinctly labeled targets reveals the original number of molecules of each species.We can generalize the stochastic labeling process as follows. Consider a given set of copies of a single target sequence T ¼ ft 1 ;t 2 …t n g; where n is the number of copies of T. A set of labels is defined as L ¼ fl 1 ;l 2 …l m g; where m is the number of different labels. T reacts stochastically with L, such that each t becomes attached to one l. If the ls are in nondepleting excess, each t will choose one l randomly, and will take on a new identity l i t j ; where l i is chosen from L and j is the jth copy from the set of n molecules. We identify each new molecule l i t j by its label subs...

Epidemiological studies suggested drinking green tea is inversely associated with esophageal cancer but results remain inconclusive. Moreover, inconsistent observations found high temperature drinks are associated with esophageal cancer. A population-based case-control study was conducted in a high-risk area (Dafeng) and a low-risk area (Ganyu) of esophageal cancer in Jiangsu province China from 2003 to 2007. It aimed to explore green tea drinking and tea temperature with the risk of esophageal cancer, and to compare the difference between different risk regions. Using identical protocols, 1,520 cases and 3,879 healthy controls were recruited as study subjects in 2 regions. Detailed information was collected to assess green tea drinking habits. Unconditional logistic regression was used to obtain OR and 95% CI. Results showed that ever drinking green tea elevated OR in both counties (Dafeng OR 5 1.2, 95% CI 5 0.9-1.5; Ganyu: OR 5 1.9, 95% CI 5 1.4-2.4). Drinking tea at high temperature was found to increase cancer risk in both areas (Dafeng: OR 5 1.9, 95% CI 5 1.2-2.9; Ganyu OR 5 3.1 95% CI 5 2.2-4.3). However, after further adjustment for tea temperature, ever drinking tea was not related to cancer in either county (Dafeng: OR 5 1.0, 95% CI 5 0.7-1.3; Ganyu: OR 5 1.3, 95% CI 5 0.9-1.7). For dose-response relationships, we observed positive relationship with monthly consumption of tea (p for trend 5 0.067) and tea concentration (p for trend 5 0.006) after further adjustment for tea temperature. In conclusion, green tea drinking was not inversely associated with esophageal cancer in this study. However, drinking tea at high temperatures significantly increased esophageal cancer risk. There was no obvious difference of green tea drinking between low-and high-risk areas. '

COVID-19 threatens the world. Social distancing is a significant factor in determining the spread of this disease, and social distancing is strongly affected by the local travel behaviour of people in large cities. In this study, we analysed the changes in the local travel behaviour of various population groups in Hong Kong, between 1 January and 31 March 2020, by using second-by-second smartcard data obtained from the Mass Transit Railway Corporation (MTRC) system. Due to the pandemic, local travel volume decreased by 43%, 49% and 59% during weekdays, Saturdays and Sundays, respectively. The local travel volumes of adults, children, students and senior citizens decreased by 42%, 86%, 73% and 48%, respectively. The local travel behaviour changes for adults and seniors between non-pandemic and pandemic times were greater than those between weekdays and weekends. The opposite was true for children and students. During the pandemic, the daily commute flow decreased by 42%. Local trips to shopping areas, amusement areas and borders decreased by 42%, 81% and 99%, respectively. The effective reproduction number ( R t ) of COVID-19 had the strongest association with daily population use of the MTR 7-8 days earlier.

The environmental risk factors, together with genetic factors and gene-environmental interactions might be the main reason for this high-risk gradient in Jiangsu Province, China.

Endothelial dysfunction and decreased production of nitric oxide (NO) by endothelial NO synthase (eNOS) are implicated in the pathogenesis of hypertension and insulin resistance. Because the potential influence of increased eNOS expression/ activity on these parameters is unclear, the present study examined the effects of eNOS gene therapy on insulin resistance and blood pressure alterations in a fructose-induced hypertension model in rats. As predicted, 2 weeks of fructose consumption in the drinking water resulted in elevated systolic blood pressure and insulin resistance. These and other physiologic alterations were reversed within 2 weeks after a single intravenous injection of a vector containing the human eNOS cDNA (pcDNA3.1-eNOS), whereas injection of an empty vector (pcDNA3.1) was without effect. In support of the beneficial effects of pcDNA3.1-eNOS treatment being because of enhanced eNOS expression and activity, increased eNOS protein levels were documented in aorta, liver, kidney, and heart of fructose-treated rats injected with pcDNA3.1-eNOS, and corresponding elevations in nitrite/nitrate and cGMP concentrations were observed in urine. Furthermore, pcDNA3.1-eNOS treatment prevented fructose-induced decreases in expression levels of insulin receptor substrate-1, the p110 catalytic subunit of phosphatidylinositol 3-kinase, phosphorylated Akt, and phosphorylated AMP-activated protein kinases in liver, aorta, and skeletal muscle. The results of this study cumulatively indicate that gene therapy with human eNOS decreased fructose-induced hypertension and insulin resistance in rats and suggest potential signaling pathways that mediate these effects. These data highlight the potential utility of eNOS gene therapy in the treatment of hypertension and insulin resistance.Nitric oxide (NO), a potent vasodilator constitutively produced by endothelial nitric-oxide synthase (eNOS), is thought to be the endothelium-derived relaxing factor that mediates relaxation in response to acetylcholine, bradykinin, and substance P in vascular beds (Rees and Moncada, 1989). eNOS is the predominant vascular NO synthase isoform and is responsible for the majority of NO production in the vasculature (Moncada and Higgs, 2006). In addition to its effects on the regulation of blood pressure and regional blood flow, NO influences vascular smooth muscle proliferation and inhibits platelet aggregation and leukocyte adhesion (Moncada and Higgs, 2006).A number of lines of evidence implicate eNOS-derived NO as a pivotal regulator of blood pressure, vascular tone, and vascular homeostasis. In vivo inhibition of NO synthase activity by nonhydrolyzable analogs of L-arginine results in a dramatic increase in mean arterial blood pressure (Desjardins and Balligand, 2006), whereas mice genetically deficient in eNOS have impaired endothelium-dependent vasodilator responses to acetylcholine and are hypertensive (Huang et

Most microRNAs have a stronger inhibitory effect in estrogen receptor-negative than in estrogen receptor-positive breast cancers.