27 research outputs found
Changing trends of disease burden of stroke from 1990 to 2019 and its predictions among the Chinese population
ObjectiveThis study aimed to understand the temporal trends in the disease burden of stroke and its attributable risk factors in China, along with the future trends in the next 25 years, that is important for effective prevention strategies and improvement, and to provide new insights into the age- and sex-specific incidence, prevalence, mortality, disability-adjusted life-years (DALYs) and their trends from 1990 to 2019, and the prediction in the next 25 years.MethodsThe Global Burden of Disease Study (2019) was used to extract the data on age- and sex-specific incidence, mortality, and disability-adjusted life-years (DALYs) of stroke in China, 1990–2019. We estimated the estimated annual percentage change (EAPC) to access the temporal trends of the disease burden of stroke. The R package called Nordpred was used to perform an age-period-cohort analysis to predict the prevalence of stroke.ResultsThe number of incidence cases, deaths, and DALYs of stroke increased from 1990 to 2019. Overall downward trends were observed in the age-standardized incidence rate (ASIR) from 1990 to 2019. Significant temporal trends in mortality and DALYs of stroke were observed. High systolic blood pressure, smoking, and high-sodium diet were the main driving forces for stroke. The DALYs lost attributable to smoking were different for male and female patients. In the next 25 years, the number of new cases and deaths from stroke should continue to increase. The ASIR and age-standardized mortality rate (ASMR) should show a downward trend among male and female patients.ConclusionDespite the overall rates of stroke declined over the period from 1990 to 2019, the absolute number of people affected by stroke has substantially increased. There has been a substantial increase in the burden of stroke due to risk factors and will continue to increase in the next 25 years
Dopamine Neuron Stimulating Actions of a GDNF Propeptide
BACKGROUND: Neurotrophic factors, such as glial cell line-derived neurotrophic factor (GDNF), have shown great promise for protection and restoration of damaged or dying dopamine neurons in animal models and in some Parkinson's disease (PD) clinical trials. However, the delivery of neurotrophic factors to the brain is difficult due to their large size and poor bio-distribution. In addition, developing more efficacious trophic factors is hampered by the difficulty of synthesis and structural modification. Small molecules with neurotrophic actions that are easy to synthesize and modify to improve bioavailability are needed. METHODS AND FINDINGS: Here we present the neurobiological actions of dopamine neuron stimulating peptide-11 (DNSP-11), an 11-mer peptide from the proGDNF domain. In vitro, DNSP-11 supports the survival of fetal mesencephalic neurons, increasing both the number of surviving cells and neuritic outgrowth. In MN9D cells, DNSP-11 protects against dopaminergic neurotoxin 6-hydroxydopamine (6-OHDA)-induced cell death, significantly decreasing TUNEL-positive cells and levels of caspase-3 activity. In vivo, a single injection of DNSP-11 into the normal adult rat substantia nigra is taken up rapidly into neurons and increases resting levels of dopamine and its metabolites for up to 28 days. Of particular note, DNSP-11 significantly improves apomorphine-induced rotational behavior, and increases dopamine and dopamine metabolite tissue levels in the substantia nigra in a rat model of PD. Unlike GDNF, DNSP-11 was found to block staurosporine- and gramicidin-induced cytotoxicity in nutrient-deprived dopaminergic B65 cells, and its neuroprotective effects included preventing the release of cytochrome c from mitochondria. CONCLUSIONS: Collectively, these data support that DNSP-11 exhibits potent neurotrophic actions analogous to GDNF, making it a viable candidate for a PD therapeutic. However, it likely signals through pathways that do not directly involve the GFRalpha1 receptor
Interspecies and Intraspecies Analysis of Trehalose Contents and the Biosynthesis Pathway Gene Family Reveals Crucial Roles of Trehalose in Osmotic-Stress Tolerance in Cassava
Trehalose is a nonreducing α,α-1,1-disaccharide in a wide range of organisms, and has diverse biological functions that range from serving as an energy source to acting as a protective/signal sugar. However, significant amounts of trehalose have rarely been detected in higher plants, and the function of trehalose in the drought-tolerant crop cassava (Manihot esculenta Crantz) is unclear. We measured soluble sugar concentrations of nine plant species with differing levels of drought tolerance and 41 cassava varieties using high-performance liquid chromatography with evaporative light-scattering detector (HPLC-ELSD). Significantly high amounts of trehalose were identified in drought-tolerant crops cassava, Jatropha curcas, and castor bean (Ricinus communis). All cassava varieties tested contained high amounts of trehalose, although their concentrations varied from 0.23 to 1.29 mg·g−1 fresh weight (FW), and the trehalose level was highly correlated with dehydration stress tolerance of detached leaves of the varieties. Moreover, the trehalose concentrations in cassava leaves increased 2.3–5.5 folds in response to osmotic stress simulated by 20% PEG 6000. Through database mining, 24 trehalose pathway genes, including 12 trehalose-6-phosphate synthases (TPS), 10 trehalose-6-phosphate phosphatases (TPP), and two trehalases were identified in cassava. Phylogenetic analysis indicated that there were four cassava TPS genes (MeTPS1–4) that were orthologous to the solely active TPS gene (AtTPS1 and OsTPS1) in Arabidopsis and rice, and a new TPP subfamily was identified in cassava, suggesting that the trehalose biosynthesis activities in cassava had potentially been enhanced in evolutionary history. RNA-seq analysis indicated that MeTPS1 was expressed at constitutionally high level before and after osmotic stress, while other trehalose pathway genes were either up-regulated or down-regulated, which may explain why cassava accumulated high level of trehalose under normal conditions. MeTPS1 was then transformed into tobacco (Nicotiana benthamiana). Results indicated that transgenic tobacco lines accumulated significant level of trehalose and possessed improved drought stress tolerance. In conclusion, cassava accumulated significantly high amount of trehalose under normal conditions due to multiplied trehalose biosynthesis gene families and constant expression of the active MeTPS1 gene. High levels of trehalose subsequently contributed to high drought stress tolerance
Involvement of CUL4A in Regulation of Multidrug Resistance to P-gp Substrate Drugs in Breast Cancer Cells
CUL4A encodes a core component of a cullin-based E3 ubiquitin ligase complex that regulates many critical processes such as cell cycle progression, DNA replication, DNA repair and chromatin remodeling by targeting a variety of proteins for ubiquitination and degradation. In the research described in this report we aimed to clarify whether CUL4A participates in multiple drug resistance (MDR) in breast cancer cells. We first transfected vectors carrying CUL4A and specific shCUL4A into breast cancer cells and corresponding Adr cells respectively. Using reverse transcription polymerase chain reactions and western blots, we found that overexpression of CUL4A in MCF7 and MDA-MB-468 cells up-regulated MDR1/P-gp expression on both the transcription and protein levels, which conferred multidrug resistance to P-gp substrate drugs, as determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. On the other hand, silencing CUL4A in MCF7/Adr and MDA-MB-468/Adr cells led to the opposite effect. Moreover, ERK1/2 in CUL4A-overexpressing cells was highly activated and after treatment with PD98059, an ERK1/2-specific inhibitor, CUL4A-induced expression of MDR1/P-gp was decreased significantly. Lastly, immunohistochemistry in breast cancer tissues showed that P-gp expression had a positive correlation with the expression of CUL4A and ERK1/2. Thus, these results implied that CUL4A and ERK1/2 participated in multi-drug resistance in breast cancer through regulation of MDR1/P-gp expression
Long-Chain Fluorescent Probe for Straightforward and Nondestructive Staining Mitochondria in Fixed Cells and Tissues
Normally, small-molecule fluorescent probes dependent
on the mitochondrial
membrane potential (MMP) are invalid for fixed cells and tissues,
which limits their clinical applications when the fixation of pathological
specimens is imperative. Given that mitochondrial morphology is closely
associated with disease, we developed a long-chain mitochondrial probe
for fixed cells and tissues, DMPQ-12, by installing a
C12-alkyl chain into the quinoline moiety. In fixed cells
stained with DMPQ-12, filament mitochondria and folded
cristae were observed with confocal and structural illumination microscopy,
respectively. In titration test with three major phospholipids, DMPQ-12 exhibited a stronger binding force to mitochondria-exclusive
cardiolipin, revealing its targeting mechanism. Moreover, mitochondrial
morphological changes in the three lesion models were clearly visualized
in fixed cells. Finally, by DMPQ-12, three kinds of mitochondria
with different morphologies were observed in situ in fixed muscle tissues. This work breaks the conventional concept
that organic fluorescent probes only stain mitochondria with normal
membrane potentials and opens new avenues for comprehensive mitochondrial
investigations in research and clinical settings
Spatially Dependent Fluorescent Probe for Detecting Different Situations of Mitochondrial Membrane Potential Conveniently and Efficiently
The
feedback from mitochondrial membrane potential (MMP) in different
situations (normal, decreasing, and vanishing) can reflect different
cellular status, which can be applied in biomedical research and diagnosis
of the related diseases. Thus, the efficient and convenient detection
for MMP in different situations is particularly important, yet the
operations of current fluorescent probes are complex. In order to
address this concern, we presented herein a spatially dependent fluorescent
probe composed of organic cationic salt. The experimental results
from normal and immortalized cells showed that it could accumulate
in mitochondria selectively when MMP was normal. Also, it would move
into the nucleus from mitochondria gradually with the decrease of
MMP, and finally it targeted the nucleus exclusively when MMP vanished.
According to the cell morphology, there is a straightforward spatial
boundary between the nucleus and cytoplasm where mitochondria locate;
thus, the three situations of MMP can be point-to-point indicated
just by fluorescence images of the probe: that all probes accumulate
in mitochondria corresponds to normal MMP; that probes locate both
in the mitochondria and nucleus corresponds to decreasing MMP; that
probes only target the nucleus corresponds to vanishing MMP. It is
worth noting that counterstaining results with S-11348 indicated that
the spatially dependent probe could be applied to distinguishing dead
from viable cells in the same cell population. Compared with the commercial
Cellstain-Double staining kit containing calcein-AM and propidium
iodide (PI), this probe can address this concern by itself and shorten
the testing time, which brings enormous convenience for relevant researches