ABSTRACT
BACKGROUND: Depression in late life has been associated with reduced quality of life and increased mortality. Whether the chronic fine particular matter (PM2.5) and its components exposure are contributed to the older depression symptoms remains unclear. METHOD: Middle-aged and older adults (>45 years) were selected from the China Health and Retirement Longitudinal Study during the four waves of interviews. The concentrations of PM2.5 and its major constituents were calculated using near real-time data at a spatial resolution of 10â¯km during the study period. The depressive symptom was evaluated by the Depression Center for Epidemiologic Studies Depression (CES-D)-10 score. The fix-effect model was applied to evaluate the association between PM2.5 and its major constituents with depressive symptoms. Three three-step methods were used to explore the modification role of sleep duration against the depressive symptoms caused by PM2.5 exposure. RESULTS: In our study, a total of 52,683 observations of 16,681 middle-aged and older adults were assessed. Each interquartile range (IQR) level of PM2.5 concentration exposure was longitudinally associated with a 2.6â¯% (95â¯% confidence interval [CI]: 1.3â¯%, 4.0â¯%) increase in the depression CES-D-10 score. Regarding the major components of PM2.5, OM, NO3-, and NH4+ showed the leading toxicity effects, which could increase the depression CES-D-10 score by 2.2â¯% (95â¯%CI: 1.0â¯%, 3.4â¯%), 2.2â¯% (0.6â¯%, 3.9â¯%), and 2.0â¯% (95â¯%CI: 0.6â¯%, 3.4â¯%) correspondingly. Besides, males were more susceptible to the worse depressive symptoms caused by PM2.5 and its major components exposure than female subpopulations. Shortened sleep duration might be the mediator of PM2.5-associated depressive symptoms. CONCLUSION: Our results suggest that long-term exposure to PM2.5 and its major components were associated with an increased risk for depressive symptoms in middle-aged and older adults. Reducing the leading components of PM2.5 may cost-effectively alleviate the disease burden of depression and promote healthy longevity in heavy pollutant countries.
Subject(s)
Air Pollutants , Depression , Environmental Exposure , Particulate Matter , Humans , Particulate Matter/analysis , Male , Middle Aged , Female , Depression/epidemiology , Depression/psychology , Aged , China/epidemiology , Air Pollutants/analysis , Longitudinal Studies , Environmental Exposure/statistics & numerical data , Cohort Studies , Air Pollution/adverse effects , Air Pollution/statistics & numerical dataABSTRACT
Intracerebral hemorrhage (ICH) represents one of the most severe subtypes of stroke. Due to the complexity of the brain injury mechanisms following ICH, there are currently no effective treatments to significantly improve patient functional outcomes. Curcumin, as a potential therapeutic agent for ICH, is limited by its poor water solubility and oral bioavailability. In this study, mPEG-PCL is used to encapsulate curcumin, forming curcumin nanoparticles, and utilized the intranasal administration route to directly deliver curcumin nanoparticles from the nasal cavity to the brain. By inhibiting pro-inflammatory neuroinflammation of microglia following ICH in mice, reprogramming pro-inflammatory microglia toward an anti-inflammatory function, and consequently reducing neuronal inflammatory death and hematoma volume, this approach improved blood-brain barrier damage in ICH mice and promoted the recovery of neurological function post-stroke. This study offers a promising therapeutic strategy for ICH to mediate neuroinflammatory microenvironments.
ABSTRACT
Vicia kulingiana, an endemic species, serves as a wild and underutilized vegetable traditionally consumed in China. However, ethnobotanical and chemical studies of this species are not available. This study analyzed its associated ethnobotanical knowledge, nutritional composition and aroma profile. Ethnobotanical surveys revealed its diverse traditional uses, especially as a nutritious vegetable. Further analysis showed V. kulingiana leaves to be high in protein, minerals, vitamin E, and dietary fiber. In total, 165 volatile compounds, such as terpenoids, alcohols, and ketones, were identified. Among them, ß-ionone is the most abundant compound with a relative percentage of 8.24%, followed by 2,2,4,6,6-pentamethylheptane (3.2%), 3-(4-methyl-3-pentenyl)furan (2.37%), and linalool (1.68%). Results supported the traditional uses of V. kulingiana's and highlighted its potential as a valuable food source, encouraging further research on its food applications. The documentation of ethnobotanical knowledge contributes to the conservation of this heritage.
ABSTRACT
Doxorubicin (DOX) is widely used as a chemotherapeutic agent for both hematologic and solid tumors and is a reasonable candidate for glioma treatment. However, its effectiveness is hindered by significant toxicity and drug resistance. Moreover, the presence of the blood-brain barrier (BBB) brings a crucial challenge to glioma therapy. In response, a GSH-responsive and actively targeted nanoprodrug delivery system (cRGD/PSDOX-Cur@NPs) are developed. In this system, a disulfide bond-bridged DOX prodrug (PEG-SS-DOX) is designed to release specifically in the high glutathione (GSH) tumor environment, markedly reducing the cardiotoxicity associated with DOX. To further address DOX resistance, curcumin, serving as a P-glycoprotein (P-gp) inhibitor, effectively increased cellular DOX concentration. Consequently, cRGD/PSDOX-Cur@NPs exhibited synergistic anti-tumor effects in vitro. Furthermore, in vivo experiments validated the superior BBB penetration and brain-targeting abilities of cRGD/PSDOX-Cur@NPs, showcasing the remarkable potential for treating both subcutaneous and orthotopic gliomas. This research underscores that this nanoprodrug delivery system presents a novel approach to inhibiting glioma while addressing resistance and systemic toxicity.
Subject(s)
Doxorubicin , Drug Delivery Systems , Glioma , Prodrugs , Glioma/drug therapy , Glioma/pathology , Doxorubicin/pharmacology , Doxorubicin/chemistry , Animals , Humans , Drug Delivery Systems/methods , Cell Line, Tumor , Prodrugs/chemistry , Prodrugs/pharmacology , Blood-Brain Barrier/metabolism , Blood-Brain Barrier/drug effects , Glutathione/metabolism , Glutathione/chemistry , Nanoparticles/chemistry , Mice , Brain Neoplasms/drug therapy , Brain Neoplasms/pathology , Curcumin/chemistry , Curcumin/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacologyABSTRACT
Immune evasion has made ovarian cancer notorious for its refractory features, making the development of immunotherapy highly appealing to ovarian cancer treatment. The immune-stimulating cytokine IL-12 exhibits excellent antitumor activities. However, IL-12 can induce IFN-γ release and subsequently upregulate PDL-1 expression on tumor cells. Therefore, the tumor-targeting folate-modified delivery system F-DPC is constructed for concurrent delivery of IL-12 encoding gene and small molecular PDL-1 inhibitor (iPDL-1) to reduce immune escape and boost anti-tumor immunity. The physicochemical characteristics, gene transfection efficiency of the F-DPC nanoparticles in ovarian cancer cells are analyzed. The immune-modulation effects of combination therapy on different immune cells are also studied. Results show that compared with non-folate-modified vector, folate-modified F-DPC can improve the targeting of ovarian cancer and enhance the transfection efficiency of pIL-12. The underlying anti-tumor mechanisms include the regulation of T cells proliferation and activation, NK activation, macrophage polarization and DC maturation. The F-DPC/pIL-12/iPDL-1 complexes have shown outstanding antitumor effects and low toxicity in peritoneal model of ovarian cancer in mice. Taken together, our work provides new insights into ovarian cancer immunotherapy. Novel F-DPC/pIL-12/iPDL-1 complexes are revealed to exert prominent anti-tumor effect by modulating tumor immune microenvironment and preventing immune escape and might be a promising treatment option for ovarian cancer treatment.
ABSTRACT
Despite the tremendous progress in cancer treatment in recent decades, cancers often become resistant due to multiple mechanisms, such as intrinsic or acquired multidrug resistance, which leads to unsatisfactory treatment effects or accompanying metastasis and recurrence, ultimately to treatment failure. With a deeper understanding of the molecular mechanisms of tumors, researchers have realized that treatment designs targeting tumor resistance mechanisms would be a promising strategy to break the therapeutic deadlock. Nanodelivery systems have excellent physicochemical properties, including highly efficient tissue-specific delivery, substantial specific surface area, and controllable surface chemistry, which endow nanodelivery systems with capabilities such as precise targeting, deep penetration, responsive drug release, multidrug codelivery, and multimodal synergy, which are currently widely used in biomedical researches and bring a new dawn for overcoming cancer resistance. Based on the mechanisms of tumor therapeutic resistance, this review summarizes the research progress of nanodelivery systems for overcoming tumor resistance to improve therapeutic efficacy in recent years and offers prospects and challenges of the application of nanodelivery systems for overcoming cancer resistance.
Subject(s)
Nanomedicine , Neoplasms , Humans , Drug Resistance, Neoplasm , Nanoparticle Drug Delivery System , Neoplasms/drug therapy , Treatment FailureABSTRACT
BACKGROUND: There is little evidence on whether PM2.5 and ground surface ozone have consistent effects on increased individual medical costs, and there is a lack of evidence on causality in developing countries. METHODS: This study utilized balanced panel data from 2014, 2016, and 2018 waves of the Chinese Family Panel Study. The Tobit model was developed within a counterfactual causal inference framework, combined with a correlated random effects and control function approach (Tobit-CRE-CF), to explore the causal relationship between long-term exposure to air pollution and medical costs. We also explored whether different air pollutants exhibit comparable effects. RESULTS: This study encompassed 8928 participants and assessed various benchmark models, highlighting the potential biases from failing to account for air pollution endogeneity or overlooking respondents without medical costs. Using the Tobit-CRE-CF model, significant effects of air pollutants on increased individual medical costs were identified. Specifically, margin effects for PM2.5 and ground-level ozone signifying that a unit increase in PM2.5 and ground-level ozone results in increased total medical costs of 199.144 and 75.145 RMB for individuals who incurred fees in the previous year, respectively. CONCLUSIONS: The results imply that long-term exposure to air pollutants contributes to increased medical costs for individuals, offering valuable insights for policymakers aiming to mitigate air pollution's consequences.
Subject(s)
Air Pollutants , Ozone , Humans , Ozone/adverse effects , Ozone/analysis , Particulate Matter/adverse effects , Environmental Exposure/adverse effects , Environmental Exposure/analysis , Air Pollutants/adverse effects , Air Pollutants/analysis , ChinaABSTRACT
Air pollution remains a risk factor for the global burden of disease. Middle-aged and older people are more susceptible to air pollution because of their declining physical function and are more likely to develop diseases from long-term air pollution exposure. Studies of the effects of air pollution on cognitive function in middle-aged and older adults have been inconsistent. More representative and definitive evidence is needed. This study analysed data from the Chinese Family Panel Study, an ongoing nationwide prospective cohort study, collected in waves 2014, 2016 and 2018. Rigorously tested instrument was selected for analysis and participants' PM2.5 and instrument exposures were assessed using high-precision satellite data. The causal relationship between long-term exposure to air pollution and poor cognitive function in middle-aged and older adults was investigated using the Correlated Random Effects Control Function (CRE-CF) method within a quasi-experimental framework. This study included a total of 7042 participants aged 45 years or older. A comparison of CRE-CF with other models (OLS model, ordered probit model, and ordered probit-CRE model) demonstrated the necessity of using CRE-CF given the endogeneity of air pollution. The credibility and validity of the instrumental variable were verified. In the CRE-CF model, long-term exposure to PM2.5 was found to accelerate cognitive decline in middle-aged and older adults (coefficients of -0.159, -0.336 and -0.244 for the total cognitive, verbal and mathematical scores, respectively). Taken together, these results suggest that chronic exposure to ambient air pollution is associated with cognitive decline in middle-aged and older adults, which highlights the need for appropriate protective policies.
Subject(s)
Air Pollutants , Air Pollution , Cognitive Dysfunction , Middle Aged , Humans , Aged , Air Pollutants/adverse effects , Air Pollutants/analysis , Prospective Studies , Particulate Matter/adverse effects , Particulate Matter/analysis , Environmental Exposure/adverse effects , Environmental Exposure/analysis , Air Pollution/adverse effects , Air Pollution/analysis , Cognitive Dysfunction/chemically induced , Cognitive Dysfunction/epidemiologyABSTRACT
The transportation processes during aquatic systems regulate the ultimate chemistry of dissolved organic matter (DOM), and in recent years, climate changes and human activities have altered the hydrological patterns of many rivers and lakes, which generated some severe issues, such as hydrological isolation. However, how hydrological isolation affects variations of DOM chemistry in large lake systems is still poorly understood. Here, optical properties and molecular compositions of DOM samples derived from a large river-connected lake (Poyang Lake, China) and its nearby seasonal sub-lakes (formed by hydrological isolation) were characterized using Fourier transform ion cyclotron resonance mass spectrometry (FT ICR MS) and ultraviolet-visible (UV-Vis) spectroscopy. The results revealed more abundance of organic matter in sub-lakes than that in the main lake according to high dissolved organic carbon (DOC) concentrations and absorption coefficients (a254 and a280). Large proportions of CHOS formulas were identified by FT ICR MS in sub-lakes DOM, which were produced through Kraft reactions (sulfide/bisulfide + lignin CHO â CHOS) in the interface of sediment/water, and greatly contributed to aliphatic compounds. In addition, obvious variations of compounds (such as polyphenols, highly unsaturated and aliphatic compounds) and lability of DOM were observed between sub-lakes and main lakes, which were mainly caused by the different degradation pathways of DOM (photodegradation in sub-lakes while biodegradation in the main lake). Our results demonstrated that hydrological isolation has significant impacts on DOM chemistry, and provides an improved understanding of the DOM biogeochemistry process in Poyang Lake and supports the management of the large lake systems.
Subject(s)
Lakes , Rivers , China , Dissolved Organic Matter , Humans , Lakes/chemistry , Lignin , Polyphenols , Sulfides , WaterABSTRACT
The world is aging, posing a challenge to public health. Air pollution is increasingly recognized as an important environmental risk factor, with effects on both physical and mental health. Considering the vulnerability of older adults, they tend to have more prevalent comorbidities that may lead to broader consequences. However, evidence to comprehensively assess the causal effects of long-term air pollution exposure on the physical and mental health of older adults remains limited and inconsistent, especially in developing countries. The longitudinal data from the Chinese Family Panel Study (a representative Chinese national cohort study) for 2012, 2014, 2016, and 2018 were included in this study. The Correlated Random Effects Control Function method (CRE-CF) in a counterfactual causal inference framework was employed to explore the causal relationship between long-term exposure to air pollution and physical and mental health and self-rated health status in middle-aged and older adults, considering the ordered categorical nature of health outcomes. The appropriate instrumental variable was selected and validated. This study included 5846 participants aged >45 years in 2012. In the CRE-CF model for activities of daily living (ADLs, positively associated with physical health), subjective memory impairment (SMI, negatively associated with memory health) and self-rated health status in middle-age and older adults, the coefficient of PM2.5 is -0.069, 0.102, and 0.106 respectively, and all statistically significant at 5% level, which suggests that chronic exposure to air pollutants had significant negative effects on ADLs, SMI and self-rated health in middle-aged and older adults. The findings suggest that long-term exposure to air pollutants can impair the health of middle-aged and older adults across the board, including physical and mental health. In the context of an aging society, the findings of this study will provide tremendous implications for the authority to protect them from damage caused by long-term exposure to air pollutants.
Subject(s)
Air Pollutants , Air Pollution , Activities of Daily Living , Aged , Air Pollutants/adverse effects , Air Pollutants/analysis , Air Pollution/adverse effects , Air Pollution/analysis , China/epidemiology , Cohort Studies , Environmental Exposure/analysis , Humans , Mental Health , Middle Aged , Particulate Matter/analysisABSTRACT
The effects of air pollution on adolescents need further consideration. Although there is evidence that maternal exposure to air pollution may affect the cognitive function of offspring, relevant studies remain limited and inconsistent, with a lack of studies assessing the causal effects and evidence from developing countries. Using data from Chinese Family Panel Studies, a representative Chinese nationwide cohort study, OLS combined with instrumental variable + two-stage least square (IV+2SLS) was used to explore the causal effects of exposure to PM2.5 concentrations during pregnancy on the cognitive function of offspring when they become adolescents. After detailed argumentation and multiple testing, Planetary Boundary Layer Height (PBLH) and Surface Pressure (SP) were selected as the instrumental variables for this study. One thousand five hundred fifty-five adolescents participated in this study, with a mean age of 13.3 years (sd = 2.3). There were 706 females (45.4%), the mean maternal PM2.5 exposure concentration was 64.9 µg/m3, and recorded a mean cognitive function score of 38.1 (sd = 9.4). The OLS results found that maternal exposure to air pollution increased cognitive function in offspring adolescents, corroborating the presence of endogeneity. Multi-domain knowledge, the results of the weak instrumental variable assessments of F-tests (F = 237 > 10) and Stock-yogo tests (minimum eigenvalue statistic = 153.16 > 16.38), and the results of the Hansen J overidentification test (p > 0.05) verified the plausibility and validity of the instrumental variables. The IV+2SLS results, following causal modeling, showed that PM2.5 exposure during pregnancy impairs the cognitive ability of offspring adolescents (ß = -0.040, p < 0.05). Robustness tests also validated the results. This study provides important policy implications for developing countries on protecting their adolescents and reminds parents that the protection of adolescents from air pollution should begin from conception.
Subject(s)
Air Pollutants , Particulate Matter , Adolescent , Air Pollutants/analysis , China , Cognition , Cohort Studies , Female , Humans , Particulate Matter/analysis , PregnancyABSTRACT
Intracerebral hemorrhage (ICH) is a devastating subtype of stroke with high morbidity and mortality. However, there is no effective therapy method to improve its clinical outcomes to date. Here we report an injectable gelatin hydrogel that is capable of suppressing inflammation and enhancing functional recovery in a mouse model of ICH. Thiolated gelatin was synthesized by EDC chemistry and then the hydrogel was formed through Michael addition reaction between the thiolated gelatin and polyethylene glycol diacrylate. The hydrogel was characterized by scanning electron microscopy, porosity, rheology, and cytotoxicity before evaluating in a mouse model of ICH. The in vivo study showed that the hydrogel injection into the ICH lesion reduced the neuron loss, attenuated the neurological deficit post-operation, and decreased the activation of the microglia/macrophages and astrocytes. More importantly, the pro-inflammatory M1 microglia/macrophages polarization was suppressed while the anti-inflammatory M2 phenotype was promoted after the hydrogel injection. Besides, the hydrogel injection reduced the release of inflammatory cytokines (IL-1ß and TNF-α). Moreover, integrin ß1 was confirmed up-regulated around the lesion that is positively correlated with the M2 microglia/macrophages. The related mechanism was proposed and discussed. Taken together, the injectable gelatin hydrogel suppressed the inflammation which might contribute to enhance the functional recovery of the ICH mouse, making it a promising application in the clinic.
ABSTRACT
BACKGROUND AND PURPOSE: Brainstem hemorrhage (BSH) is the most devastating subtype of intracerebral hemorrhage (ICH) with the highest mortality ranging from 56 % to 61.2 %. However, there is no effective medical or surgical therapy to improve its outcomes in clinic to date due to lack of understanding of its injury mechanisms. Herein, we explored the brainstem iron overload and injury in a rat model of BSH. METHODS: Neurological scores were examined on day 1, 3, and 7 after modeling, and mortality of the rats was recorded to draft a survival curve. Rats were monitored by MRI using T2 and susceptibility weighted imaging (SWI) before sacrifice for examination of histology and immunofluorescence on day 1, 3, and 7. RESULTS: BSH rats had a high mortality of 56 % and demonstrated the severe neurological deficits mimicking the clinical conditions. SWI showed that the same increasing tendency in change of hypointense area with that in iron deposition by Perls staining from day 1 to 7. Expression of heme oxygenase 1 (HO-1) and generation of reactive oxygen species (ROS) had similar tendency and both peaked on day 3. Neuronal degeneration occurred and stayed elevated from day 1 to 7, while myelin sheath injury was initially observed on day 1 but without significant difference within 7 days. CONCLUSIONS: The time courses of erythrocyte lysis, HO-1 expression, iron deposition and ROS generation are related to each other after BSH. Besides, brainstem injury including neuronal degeneration and myelin damage were observed and discussed.
Subject(s)
Brain Stem/blood supply , Brain Stem/metabolism , Cerebral Hemorrhage/metabolism , Iron Overload/metabolism , Iron/metabolism , Animals , Brain Stem/pathology , Brain Stem/physiopathology , Cerebral Hemorrhage/pathology , Cerebral Hemorrhage/physiopathology , Disease Models, Animal , Erythrocytes/metabolism , Heme Oxygenase (Decyclizing)/metabolism , Hemolysis , Iron Overload/pathology , Iron Overload/physiopathology , Male , Myelin Sheath/metabolism , Myelin Sheath/pathology , Nerve Degeneration , Rats, Sprague-Dawley , Reactive Oxygen Species/metabolism , Time FactorsABSTRACT
Intracerebral hemorrhage (ICH) is a devastating subtype of stroke that is associated with high morbidity and mortality. However, up to now, there are no effective prevention methods or specific therapies to improve its clinical outcomes. Herein, we explore preliminarily the efficacy of crocin, a carotenoid extracted from the stigma of saffron known for its anti-oxidation and free radical scavenging activities, in a mouse ICH model induced with collagenase infusion. Crocin or saline was administrated 6â¯h after ICH and then every 12â¯h for up to 7 days. Neurological scores were examined on days 1, 3, and 7 after ICH. Mice were sacrificed after1, 3, and 7 days of crocin treatment for examination of histology and immunohistochemistry. The results showed that oral administration of crocin attenuated the neurological deficits and reduced the myelin loss, neuron degeneration, iron deposition, reactive oxygen species (ROS) production and heme oxygenase-1 (HO-1) expression in the early stage of ICH, making it potential to be an ideal candidate for medical therapy of ICH in clinic.
Subject(s)
Carotenoids/pharmacology , Cerebral Hemorrhage/drug therapy , Nervous System Diseases/drug therapy , Animals , Antioxidants/pharmacology , Brain/metabolism , Brain Edema/drug therapy , Carotenoids/metabolism , Collagenases/metabolism , Disease Models, Animal , Heme Oxygenase-1/metabolism , Male , Mice , Mice, Inbred C57BL , Nerve Degeneration/metabolism , Reactive Oxygen Species/metabolism , Stroke/pathologyABSTRACT
BACKGROUND: Brainstem hemorrhage (BSH) is the most dangerous and devastating subtype of intracerebral hemorrhage and is associated with high morbidity and mortality. However, to date, no effective prevention methods or specific therapies have been available to improve its clinical outcomes. We preliminarily explored the efficacy of deferoxamine (DFO), a clinical chelator known for its iron-scavenging activities, in a rat model of BSH induced with collagenase infusion. METHODS: DFO or saline was administrated 6 hours after BSH induction and then every 12 hours for ≤7 days. The survival curve of the rats was created, and the neurological scores were examined on days 1, 3, and 7 after BSH. The rats were sacrificed after 1, 3, and 7 days of DFO treatment for histological examination and immunohistochemistry. RESULTS: The results showed that administration of DFO delayed erythrocytes lysis, reduced iron deposition, reduced reactive oxygen species generation, reduced heme oxygenase-1 expression, and alleviated brain injury such as neuron degeneration and myelin sheath injury. However, DFO did not improve the survival rate and neurobehavioral outcomes in this model. CONCLUSIONS: Administration of DFO had limited therapeutic effects on collagenase-induced brainstem hemorrhage in rats. Some potential explanations were proposed, and more preclinical work is required to clarify the controversial curative effect of DFO in ICH.
Subject(s)
Brain Stem Hemorrhage, Traumatic/complications , Chelating Agents/therapeutic use , Deferoxamine/therapeutic use , Iron Overload/drug therapy , Iron Overload/etiology , Animals , Brain Stem Hemorrhage, Traumatic/chemically induced , Collagenases , Heme Oxygenase-1/metabolism , Immunohistochemistry , Male , Myelin Sheath/pathology , Nerve Degeneration/prevention & control , Nervous System Diseases/etiology , Nervous System Diseases/prevention & control , Rats , Rats, Sprague-Dawley , Reactive Oxygen Species/metabolism , Survival AnalysisABSTRACT
BACKGROUND AND OBJECTIVES: The overall purpose of this study was to investigate the role of cytochrome C oxidase (CcO) in preventing ischemia reperfusion-induced cardiac injury through gaseous signaling molecule pathways. MATERIALS AND METHODS: We used CcO inhibitor, potassium cyanide (KCN) to mimic the pre-treatment of gaseous signaling molecules in a global ischemia/reperfusion (IR) injury model in rats. Intracellular reactive oxygen species (ROS) was determined by measuring mitochondrial H2O2 and mitochondrial complex activity. RESULTS: KCN pre-treatment led to decreased infarction area after IR injury and improved cardiac function. KCN pre-treated group challenged with IR injury was associated with reduced ROS production through inhibition of activity and not downregulation of CcO expression. In addition, KCN pre-treatment was associated with enhanced expression and activity of mitochondrial antioxidase, suggesting the role of CcO in regulating IR injury through oxidative stress. CONCLUSION: KCN pre-treatment reduced the severity of IR injury. The potential mechanism could be increased endogenous anti-oxidase activity and consequently, the enhanced clearance of ROS.
ABSTRACT
MicroRNAs (miRNAs) are small non-coding RNAs that play vital roles in plant abiotic stress responses via cleavage or translational inhibition of their target mRNAs. Populus euphratica is a typical stress-resistant sessile organism that grows in desert areas. Here, we identified sequences of 12 miRNA precursors from 11 families and 13 mature miRNAs from 12 families by PCR amplification in P. euphratica. To detect expression differences in mature miRNAs and their precursors under dehydration and high salinity shock in P. euphratica, we examined 14 miRNA precursors from 13 miRNA families and 17 mature miRNAs from 17 miRNA families using the SYBR Green RT-PCR assay. This is the first report of expression profiles for both precursor and mature miRNAs in P. euphratica. By profiling both the mature miRNAs and the precursors under abiotic stress shock, it was possible to identify miRNA whose processing is regulated during stress shock environments. A majority of the genes predicted to be targets for plant miRNAs are involved in development, stress resistance and metabolic processes. We have cloned and experimentally identified in vivo five of the predicted target genes and quantified the five target mRNAs from the same RNA sample simultaneously. Based on this study, we propose some regulatory pathways that illustrate the important role that miRNAs play in response to abiotic stress shock in P. euphratica.