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BACKGROUND AND AIMS: Emerging evidence has raised an obesity paradox in observational studies of body mass index (BMI) and health among the oldest-old (aged ≥80 years), as an inverse relationship of BMI with mortality was reported. This study was to investigate the causal associations of BMI, waist circumference (WC), or both with mortality in the oldest-old people in China. METHODS: A total of 5306 community-based oldest-old (mean age 90.6 years) were enrolled in the Chinese Longitudinal Healthy Longevity Survey (CLHLS) between 1998 and 2018. Genetic risk scores were constructed from 58 single-nucleotide polymorphisms (SNPs) associated with BMI and 49 SNPs associated with WC to subsequently derive causal estimates for Mendelian randomization (MR) models. One-sample linear MR along with non-linear MR analyses were performed to explore the associations of genetically predicted BMI, WC, and their joint effect with all-cause mortality, cardiovascular disease (CVD) mortality, and non-CVD mortality. RESULTS: During 24 337 person-years of follow-up, 3766 deaths were documented. In observational analyses, higher BMI and WC were both associated with decreased mortality risk [hazard ratio (HR) 0.963, 95% confidence interval (CI) 0.955-0.971 for a 1-kg/m2 increment of BMI and HR 0.971 (95% CI 0.950-0.993) for each 5â cm increase of WC]. Linear MR models indicated that each 1 kg/m2 increase in genetically predicted BMI was monotonically associated with a 4.5% decrease in all-cause mortality risk [HR 0.955 (95% CI 0.928-0.983)]. Non-linear curves showed the lowest mortality risk at the BMI of around 28.0â kg/m2, suggesting that optimal BMI for the oldest-old may be around overweight or mild obesity. Positive monotonic causal associations were observed between WC and all-cause mortality [HR 1.108 (95% CI 1.036-1.185) per 5â cm increase], CVD mortality [HR 1.193 (95% CI 1.064-1.337)], and non-CVD mortality [HR 1.110 (95% CI 1.016-1.212)]. The joint effect analyses indicated that the lowest risk was observed among those with higher BMI and lower WC. CONCLUSIONS: Among the oldest-old, opposite causal associations of BMI and WC with mortality were observed, and a body figure with higher BMI and lower WC could substantially decrease the mortality risk. Guidelines for the weight management should be cautiously designed and implemented among the oldest-old people, considering distinct roles of BMI and WC.
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Índice de Masa Corporal , Análisis de la Aleatorización Mendeliana , Circunferencia de la Cintura , Humanos , Femenino , Masculino , Anciano de 80 o más Años , China/epidemiología , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/genética , Polimorfismo de Nucleótido Simple , Obesidad/genética , Obesidad/mortalidad , Causas de Muerte , Factores de Riesgo , MortalidadRESUMEN
Cancer is considered as the second leading cause of mortality, and cancer incidence is still growing rapidly worldwide, which poses an increasing global health burden. Although chemotherapy is the most widely used treatment for cancer, its effectiveness is limited by drug resistance and severe side effects. Mitophagy is the principal mechanism that degrades damaged mitochondria via the autophagy/lysosome pathway to maintain mitochondrial homeostasis. Emerging evidence indicates that mitophagy plays crucial roles in tumorigenesis, particularly in cancer therapy. Mitophagy can exhibit dual effects in cancer, with both cancer-inhibiting or cancer-promoting function in a context-dependent manner. A variety of natural compounds have been found to affect cancer cell death and display anticancer properties by modulating mitophagy. In this review, we provide a systematic overview of mitophagy signaling pathways, and examine recent advances in the utilization of natural compounds for cancer therapy through the modulation of mitophagy. Furthermore, we address the inquiries and challenges associated with ongoing investigations concerning the application of natural compounds in cancer therapy based on mitophagy. Overcoming these limitations will provide opportunities to develop novel interventional strategies for cancer treatment.
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Mitofagia , Neoplasias , Humanos , Autofagia , Muerte Celular , Mitocondrias/metabolismo , Mitofagia/fisiología , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismoRESUMEN
Background and Objectives: Physical function deterioration is always accompanied by a cognitive decline in older adults. However, evidence is lacking for the long-term simultaneous changing patterns of cognition and physical frailty and their associations with mortality among older adults. Research Design and Methods: This study included 8,231 adults aged ≥65 with a baseline and at least one follow-up assessment of both cognition and physical frailty from the 2007-2018 Chinese Longitudinal Healthy Longevity Survey. Physical frailty (FRAIL phenotype) and cognition (Mini-Mental State Examination) were applied. Group-based joint trajectory modeling was used to fit the joint trajectories of cognition and physical frailty. Cox proportional hazards model was used to evaluate the trajectory-mortality associations. Results: Three distinct joint trajectories were identified: no joint progression (34.4%), moderate joint progression (47.0%), and rapid joint progression (18.6%). During a median follow-up of 8.3 years, the rapid joint progression group, compared to the no joint progression, had the highest risk for all-cause mortality (hazard ratio (HR), 3.37 [95% CI: 2.99-3.81]), cardiovascular (CVD) mortality (3.21 [2.08-4.96]) and non-CVD mortality (2.99 [2.28-3.92]), respectively. Joint trajectory was found to be more predictive of mortality as compared to baseline measures of cognition and/or frailty (C-statistic ranged from 0.774 to 0.798). Higher changing rates of cognition and frailty were observed among all-cause decedents compared to CVD and non-CVD decedents over a 45-year span (aged 65-110) before death. Discussion and Implications: Our study suggested that subjects with the worst cognitive decline and severest physical frailty progression were at the highest risk for all-cause and cause-specific mortality. Our findings expand the limited prior knowledge on the dynamic course of cognition and frailty.
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What is already known about this topic?: Previous research indicates that non-occupational physical activity can reduce mortality risk. Nevertheless, the relationship between occupational physical activity and health improvements has not been consistently established. What is added by this report?: The study found that regular exercise and leisure activities reduced the risk of all-cause mortality. However, the combination of exercise and leisure activities demonstrated more substantial benefits. Additionally, no meaningful association was identified between physical work and mortality risk within the older population. What are the implications for public health practice?: It may be beneficial to encourage older adults to engage in regular exercise and to partake actively in leisure activities. Combining these two elements might yield greater benefits than regular exercise alone.
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This paper addresses the accurate characterization of the performance of transmission control protocol (TCP) for end-to-end transport services over free-space optical (FSO) links. Unlike previous works on this topic, we introduce a second-order Markovian assumption for the variation of the TCP congestion window to capture the memory from turbulence channels and further propose a Markov chain model that maps two consecutive congestion windows along time into the state space to interpret TCP operations. The analytical expression of steady-state probability distribution vector of the proposed model in general cases where relay routers exist behind the TCP connection is derived, based on which the throughput efficiency of TCP is formulated. The high accuracy of the proposed model is verified by Monte-Carlo simulations and experiments. We further analyze the impact of different link/channel parameters on the TCP performance, and discuss briefly the effectiveness of bundle protocol-based schemes for improving the performance of FSO networks from a transport layer perspective.
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OBJECTIVE: This study aims to explore the clinical effect of Tetrandrine (Tet) on progressive massive fibrosis (PMF) of pneumoconiosis. METHODS: This retrospective study collected 344 pneumoconiosis patients with PMF, and 127 were eligible for the final analysis, including 57 patients in the Tet group and 70 patients in the control group. The progress of imaging and lung function were compared between the two groups. RESULTS: After 13 months (median) of treatment, the size of PMF was smaller in the Tet group than that in the control group (1526 vs. 2306, p=0.001), and the size was stable in the Tet group (1568 vs. 1526, p= 0.381), while progressed significantly in the control group (2055 vs. 2306, p=0.000). The small nodule profusion and emphysema were also milder than that in the control group (6.0 vs. 7.5, p=0.046 and 8.0 vs. 12, p=0.016 respectively). Pulmonary ventilation function parameters FVC and FEV1 improved in the Tet group (3222 vs. 3301, p=0.021; 2202 vs. 2259, p=0.025 respectively) and decreased in the control group (3272 vs. 3185, p= 0.00; 2094 vs. 1981, p=0.00 respectively). FEV1/FVC was also significantly higher in the Tet group than that in the control group (68.45vs. 60.74, p=0.001). However, similar result was failed to observed for DLco%, which showed a significant decrease in both groups. CONCLUSION: Tet has shown great potential in the treatment of PMF by slowing the progression of pulmonary fibrosis and the decline of lung function.
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Neumoconiosis , Fibrosis Pulmonar , Humanos , Estudios Retrospectivos , Neumoconiosis/complicaciones , Neumoconiosis/diagnóstico por imagen , Neumoconiosis/tratamiento farmacológico , Pulmón , Fibrosis Pulmonar/diagnóstico por imagen , Fibrosis Pulmonar/tratamiento farmacológico , Fibrosis Pulmonar/patologíaRESUMEN
An open jet wind tunnel has low-frequency pressure pulsation in common wind speed range due to its unique structural form, which seriously damages the quality of flow field in the test section. The low-frequency pressure fluctuation performance and control mechanism of Jilin University open jet and return flow wind tunnel are investigated by experiments and numerical simulation. The results show that the low-frequency pressure fluctuation is a narrow pulse phenomenon that only occurs in certain intervals, and several velocity intervals may be found in the same wind tunnel. The reliability of the numerical simulation is verified by comparing the peak frequency and amplitude of pressure fluctuation in numerical simulation and wind tunnel tests. A simplified model similar to and amplifying the phenomenon is established. The flow structure and vortex evolution are analyzed via detached eddy simulation. In the test section, large-scale shedding vortices are formed at the nozzle exit, introducing periodic pulsating instantaneous velocity and acting with the collector to form an edge-feedback. This acoustic feedback forms resonance with the pipeline circuit, resulting in poor flow field quality. In accordance with the mechanism of nozzle jet, two methods of controlling pulsation are proposed: spoiler and flow-follow device. The study shows that the effects of two methods are abrupt, and the frequency of pressure pulsation is changed. The spoiler destroys the complete structure of vortex ring in free jet and develops into a complementary double vortex ring structure, which is highly sensitive to size factors. The flow-follow device supplements the velocity loss of the free jet at the nozzle and develops into a double vortex ring with master-slave structure in the middle of the test section. Its vibration reduction effect is greatly affected by the flow velocity. It takes effect in an appropriate range where the flow velocity is higher than the nozzle velocity. If the follow velocity is extremely low, the flow-follow device cannot change the original jet structure. If the follow velocity is extremely high, the momentum of the fan will be greatly reduced, the flow field will be unstable, and another order of pulsation may be induced. This work lays a solid foundation for further understanding the aerodynamic characteristics and optimization mechanism of open jet wind tunnel.
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Koumine, an alkaloid, exerts therapeutic effects against rheumatoid arthritis (RA), and thus may have a potential application in novel treatment strategies against this disease. Herein, we investigated the regulatory effect of koumine on Th cell polarization using a "pyramid" structure model to elucidate the mechanism underlying its therapeutic effect on RA. The third layer of the model comprises the cytokine secretion layer, in which the effects of koumine on the balance of Th-related cytokines were investigated in mice with collagen-induced arthritis (CIA). Koumine showed significant therapeutic effects and reversed the imbalance of Th1/Th2 and Th17/Treg cytokines. In the Th cell polarization layer, the effects of koumine on the relative numbers of Th cell subsets in splenocytes of rats with CIA were examined. Koumine attenuated both of the increased Th1/Th2 and Th17/Treg subset ratios accompanied with its therapeutic effects. Finally, the primary cultured splenocytes from BALB/c mice were used to further investigate the effect of koumine on Th cell activation by evaluating cell proliferation induced by concanavalin A (Con A), lipopolysaccharides (LPS) and phytohemagglutinin (PHA). Koumine inhibited the cell proliferation responses and its effects on proliferation induced by Con A and PHA were greater than those by LPS, showing the relatively selective inhibition on the proliferation of Th cells. Our results suggest that koumine might restore the homeostasis of the network system with Th subsets and cytokines by inhibiting the activation of T cells, subsequently regulating the polarization of Th subsets and the downstream imbalance of pro/anti-inflammatory cytokines in RA.
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Artritis Experimental , Artritis Reumatoide , Ratones , Ratas , Animales , Lipopolisacáridos/farmacología , Artritis Reumatoide/tratamiento farmacológico , Artritis Experimental/tratamiento farmacológico , Células Th17 , Linfocitos T Reguladores , Citocinas/farmacologíaRESUMEN
Lead (Pb) is a widespread environmental contaminant, associated with a higher risk of functional impairment that can lead to frailty in older adults. However, few studies focused on the association of Pb exposure with frailty among the oldest old (aged ≥ 80 years). In this study, we aimed to assess the associations of Pb with frailty and its components in the oldest old. The included individuals were the oldest old aged ≥ 80 years who participated in a 2017 cross-sectional survey of the Healthy Aging and Biomarkers Cohort Study. Frailty was ascertained by the frailty index, which was created based on health deficits. We used logistic regression models to estimate the association of blood Pb with frailty and its components. The geometric mean and median of blood Pb were 38.51 µg/L and 36.27 µg/L among the oldest old, respectively. Compared with the first quartile of blood Pb, participants in the fourth quartile had higher risk of frailty and its components, the ORs are 1.71 (1.22-2.41), 1.99 (1.35-2.94), 1.91 (1.25-2.93), 1.57 (1.13-2.17) and 1.43 (1.05-1.96), for frailty, ADL disability, IADL disability, functional limitations, and hearing loss in the oldest old, respectively. There was a significant interaction between blood Pb and frailty in different age groups. In conclusion, our findings provide preliminary evidence that higher blood Pb may increase the risk of frailty among the oldest old by increasing the risk of disability in four physical functions: disability in ADL, disability in IADL, functional limitations, and hearing loss.
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Fragilidad , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , China/epidemiología , Estudios de Cohortes , Estudios Transversales , Fragilidad/epidemiología , Humanos , PlomoRESUMEN
Palmitoylation may be relevant to the processes of learning and memory, and even disorders, such as post-traumatic stress disorder and aging-related cognitive decline. However, underlying mechanisms of palmitoylation in these processes remain unclear. Herein, we used acyl-biotin exchange, coimmunoprecipitation and biotinylation assays, and behavioral and electrophysiological methods, to explore whether palmitoylation is required for hippocampal synaptic transmission and fear memory formation, and involved in functional modification of synaptic proteins, such as postsynapse density-95 (PSD-95) and glutamate receptors, and detected if depalmitoylation by specific enzymes has influence on glutamatergic synaptic plasticity. Our results showed that global palmitoylation level, palmitoylation of PSD-95 and glutamate receptors, postsynapse density localization of PSD-95, surface expression of AMPARs, and synaptic strength of cultured hippocampal neurons were all enhanced by TTX pretreatment, and these can be reversed by inhibition of palmitoylation with palmitoyl acyl transferases inhibitors, 2-bromopalmitate and N-(tert-butyl) hydroxylamine hydrochloride. Importantly, we also found that acyl-protein thioesterase 1 (APT1)-mediated depalmitoylation is involved in palmitoylation of PSD-95 and glutamatergic synaptic transmission. Knockdown of APT1, not protein palmitoyl thioesterase 1, with shRNA, or selective inhibition, significantly increased AMPAR-mediated synaptic strength, palmitoylation levels, and synaptic or surface expression of PSD-95 and AMPARs. Results from hippocampal tissues and fear-conditioned rats showed that palmitoylation is required for synaptic strengthening and fear memory formation. These results suggest that palmitoylation and APT1-mediated depalmitoylation have critical effects on the regulation of glutamatergic synaptic plasticity, and it may serve as a potential target for learning and memory-associated disorders.SIGNIFICANCE STATEMENT Fear-related anxiety disorders, including post-traumatic stress disorder, are prevalent psychiatric conditions, and fear memory is associated with hyperexcitability in the hippocampal CA1 region. Palmitoylation is involved in learning and memory, but mechanisms coupling palmitoylation with fear memory acquisition remain poorly understood. This study demonstrated that palmitoylation is essential for postsynapse density-95 clustering and hippocampal glutamatergic synaptic transmission, and APT1-mediated depalmitoylation plays critical roles in the regulation of synaptic plasticity. Our study revealed that molecular mechanism about downregulation of APT1 leads to enhancement of AMPAR-mediated synaptic transmission, and that palmitoylation cycling is implicated in fear conditioning-induced synaptic strengthening and fear memory formation.
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Hipocampo , Sinapsis , Animales , Hipocampo/metabolismo , Ratones , Ratones Endogámicos C57BL , Plasticidad Neuronal , Ratas , Sinapsis/metabolismo , Transmisión Sináptica/fisiologíaRESUMEN
Gelsemium elegans (G. elegans) Benth., recognized as a toxic plant, has been used as traditional Chinese medicine for the treatment of neuropathic pain and cancer for many years. In the present study, we aim to obtain the anti-tumor effects of alkaloids of G. elegans and their active components in hepatocellular carcinoma (HCC) and the potential mechanism was also further investigated. We demonstrated that sempervirine induced HCC cells apoptosis and the apoptosis was associated with cell cycle arrest during the G1 phase, up-regulation of p53 and down-regulation of cyclin D1, cyclin B1 and CDK2. Furthermore, sempervirine inhibited HCC tumor growth and enhances the anti-tumor effect of sorafenib in vivo. In addition, inactivation of Wnt/ß-catenin pathway was found to be involved in sempervirine-induced HCC proliferation. The present study demonstrated that alkaloids of G. elegans were a valuable source of active compounds with anti-tumor activity. Our findings justified that the active compound sempervirine inhibited proliferation and induced apoptosis in HCC by regulating Wnt/ß-catenin pathway.
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Translocator protein 18 kDa (TSPO) is an evolutionarily conserved 5-transmembrane domain protein, and has been considered as an important therapeutic target for the treatment of pain. We have recently reported the in vitro and in vivo pharmacological characterization of koumine as a TSPO positive allosteric modulator (PAM), more precisely ago-PAM. However, the probe dependence in the allostery of koumine is an important question to resolve, and the possible analgesic mechanism of koumine remains to be clarified. Here, we report the in vivo evaluation of the allostery of koumine when orthosteric ligand PK11195 was used and preliminarily explore the possible analgesic mechanism of koumine associated with neurosteroids. We find that koumine is an ago-PAM of the PK11195-mediated analgesic effect at TSPO, and the analgesic mechanism of this TSPO ago-PAM may be associated with neurosteroids as the analgesic effects of koumine in the formalin-induced inflammatory pain model and chronic constriction injury-induced neuropathic pain model can be antagonized by neurosteroid synthesis inhibitor aminoglutethimide. Although our results cannot fully clarify the allosteric modulatory effect of koumine, it further prove the allostery in TSPO and provide a solid foundation for koumine to be used as a new clinical candidate drug to treat pain.
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Koumine is an alkaloid that displays notable activity against inflammatory and neuropathic pain, but its therapeutic target and molecular mechanism still need further study. Translocator protein 18 kDa (TSPO) is a vital therapeutic target for pain treatment, and recent research implies that there may be allostery in TSPO. Our previous competitive binding assay hint that koumine may function as a TSPO positive allosteric modulator (PAM). Here, for the first time, we report the pharmacological characterization of koumine as a TSPO PAM. The results imply that koumine might be a high-affinity ligand of TSPO and that it likely acts as a PAM since it could delay the dissociation of 3H-PK11195 from TSPO. Importantly, the allostery was retained in vivo, as koumine augmented Ro5-4864-mediated analgesic and anti-inflammatory effects in several acute and chronic inflammatory and neuropathic pain models. Moreover, the positive allosteric modulatory effect of koumine on TSPO was further demonstrated in cell proliferation assays in T98G human glioblastoma cells. In summary, we have identified and characterized koumine as a TSPO PAM for the treatment of inflammatory and neuropathic pain. Our data lay a solid foundation for the use of the clinical candidate koumine to treat inflammatory and neuropathic pain, further demonstrate the allostery in TSPO, and provide the first proof of principle that TSPO PAM may be a novel avenue for the discovery of analgesics.
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BACKGROUND: Infestation by tea green leafhoppers (Empoasca (Matsumurasca) onukii) can cause a series of biochemical changes in tea leaves. As a typical cell-rupture feeder, E. onukii secretes proteases while using its stylet to probe the tender shoots of tea plants (Camellia sinensis). This study identified and analyzed proteases expressed specifically in the salivary gland (SG) and gut of E. onukii through enzymatic activity assays complemented with an integrated analysis of transcriptomic and proteomic data. RESULTS: In total, 129 contigs representing seven types of putative proteases were identified. Transcript abundance of digestive proteases and enzymatic activity assays showed that cathepsin B-like protease, cathepsin L-like protease, and serine proteases (trypsin- and chymotrypsin-like protease) were highly abundant in the gut but moderately abundant in the SG. The abundance pattern of digestive proteases in the SG and gut of E. onukii differed from that of other hemipterans, including Nilaparvata lugens, Laodelphax striatellus, Acyrthosiphum pisum, Halyomorpha halys and Nephotettix cincticeps. Phylogenetic analysis showed that aminopeptidase N-like proteins and serine proteases abundant in the SG or gut of hemipterans formed two distinct clusters. CONCLUSIONS: Altogether, this study provides insightful information on the digestive system of E. onukii. Compared to five other hemipteran species, we observed different patterns of proteases abundant in the SG and gut of E. onukii. These results will be beneficial in understanding the interaction between tea plants and E. onukii.
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Microbioma Gastrointestinal , Hemípteros , Animales , Hemípteros/genética , Péptido Hidrolasas/genética , Filogenia , Proteómica , Glándulas Salivales , TranscriptomaRESUMEN
Background: The mechanistic target of rapamycin complex 1 (mTORC1) signaling has served as a promising target for therapeutic intervention of major depressive disorder (MDD), but the mTORC1 signaling underlying MDD has not been well elucidated. In the present study, we investigated whether mTORC1 signaling pathway mediates synapse loss induced by chronic stress in the hippocampus. Methods: Chronic restraint stress-induced depression-like behaviors were tested by behavior tests (sucrose preference test, forced swim test and tail suspension test). Synaptic proteins and alternations of phosphorylation levels of mTORC1 signaling-associated molecules were measured using Western blotting. In addition, mRNA changes of immediate early genes (IEGs) and glutamate receptors were measured by RT-PCR. Rapamycin was used to explore the role of mTORC1 signaling in the antidepressant effects of fluoxetine. Results: After successfully establishing the chronic restraint stress paradigm, we observed that the mRNA levels of some IEGs were significantly changed, indicating the activation of neurons and protein synthesis alterations. Then, there was a significant downregulation of glutamate receptors and postsynaptic density protein 95 at protein and mRNA levels. Additionally, synaptic fractionation assay revealed that chronic stress induced synapse loss in the dorsal and ventral hippocampus. Furthermore, these effects were associated with the mTORC1 signaling pathway-mediated protein synthesis, and subsequently the phosphorylation of associated downstream signaling targets was reduced after chronic stress. Finally, we found that intracerebroventricular infusion of rapamycin simulated depression-like behavior and also blocked the antidepressant effects of fluoxetine. Conclusion: Overall, our study suggests that mTORC1 signaling pathway plays a critical role in mediating synapse loss induced by chronic stress, and has part in the behavioral effects of antidepressant treatment.
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Objective: Understanding the heterogeneity and pathophysiology of osteoarthritis (OA) is critical to support the development of tailored disease-modifying treatments. To this aim, transcriptomics tools are highly relevant to delineate dysregulated molecular pathways and identify new therapeutic targets. Methods: We review the methodology and outcomes of transcriptomics studies conducted in OA, based on a comprehensive literature search of the PubMed and Google Scholar databases using the terms "osteoarthritis", "OA", "knee OA", "hip OA", "genes", "RNA-seq", "microarray", "transcriptomic" and "PCR" as key words. Beyond target-focused RT-qPCR, more comprehensive techniques include microarrays, RNA sequencing (RNA-seq) and single cell RNA-seq analyses. Results: The standardization of those methods to ensure the quality of both RNA extraction and sequencing is critical to get meaningful insights. Transcriptomics studies have been conducted in various tissues involved in the pathogenesis of OA, including articular cartilage, subchondral bone and synovium, as well as in the blood of patients. Molecular pathways dysregulated in OA relate to cartilage degradation, matrix and bone remodeling, neurogenic pain, inflammation, apoptosis and angiogenesis. This knowledge has direct application to patient stratification and further, to the identification of candidate therapeutic targets and biomarkers intended to monitor OA progression. Conclusion: In light of its high-throughput capabilities and ability to provide comprehensive information on major biological processes, transcriptomics represents a powerful method to support the development of new disease-modifying drugs in OA.
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Humans homozygous or hemizygous for variants predicted to cause a loss of function (LoF) of the corresponding protein do not necessarily present with overt clinical phenotypes. We report here 190 autosomal genes with 207 predicted LoF variants, for which the frequency of homozygous individuals exceeds 1% in at least one human population from five major ancestry groups. No such genes were identified on the X and Y chromosomes. Manual curation revealed that 28 variants (15%) had been misannotated as LoF. Of the 179 remaining variants in 166 genes, only 11 alleles in 11 genes had previously been confirmed experimentally to be LoF. The set of 166 dispensable genes was enriched in olfactory receptor genes (41 genes). The 41 dispensable olfactory receptor genes displayed a relaxation of selective constraints similar to that observed for other olfactory receptor genes. The 125 dispensable nonolfactory receptor genes also displayed a relaxation of selective constraints consistent with greater redundancy. Sixty-two of these 125 genes were found to be dispensable in at least three human populations, suggesting possible evolution toward pseudogenes. Of the 179 LoF variants, 68 could be tested for two neutrality statistics, and 8 displayed robust signals of positive selection. These latter variants included a known FUT2 variant that confers resistance to intestinal viruses, and an APOL3 variant involved in resistance to parasitic infections. Overall, the identification of 166 genes for which a sizeable proportion of humans are homozygous for predicted LoF alleles reveals both redundancies and advantages of such deficiencies for human survival.
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Genética Humana , Mutación con Pérdida de Función , Alelos , Apolipoproteínas L/genética , Fucosiltransferasas/genética , Variación Genética , Homocigoto , Humanos , Proteínas/genética , Cromosomas Sexuales/genética , Galactósido 2-alfa-L-FucosiltransferasaRESUMEN
Koumine (KM), one of the primary constituents of Gelsemium elegans, has been used for the treatment of inflammatory diseases such as rheumatoid arthritis, but whether KM impacts the activation of the NOD-like receptor protein 3 (NLRP3) inflammasome remains unknown. This study aimed to explore the inhibitory effect of KM on NLRP3 inflammasome activation and the underlying mechanisms both in vitro using macrophages stimulated with LPS plus ATP, nigericin or monosodium urate (MSU) crystals and in vivo using an MSU-induced peritonitis model. We found that KM dose-dependently inhibited IL-1ß secretion in macrophages after NLRP3 inflammasome activators stimulation. Furthermore, KM treatment efficiently attenuated the infiltration of neutrophils and suppressed IL-1ß production in mice with MSU-induced peritonitis. These results indicated that KM inhibited NLRP3 inflammasome activation, and consistent with this finding, KM effectively inhibited caspase-1 activation, mature IL-1ß secretion, NLRP3 formation and pro-IL-1ß expression in LPS-primed macrophages treated with ATP, nigericin or MSU. The mechanistic study showed that, KM exerted a potent inhibitory effect on the NLRP3 priming step, which decreased the phosphorylation of IκBα and p65, the nuclear localization of p65, and the secretion of TNF-α and IL-6. Moreover, the assembly of NLRP3 was also interrupted by KM. KM blocked apoptosis-associated speck-like protein containing a CARD (ASC) speck formation and its oligomerization and hampered the NLRP3-ASC interaction. This suppression was attributed to the ability of KM to inhibit the production of reactive oxygen species (ROS). In support of this finding, the inhibitory effect of KM on ROS production was completely counteracted by H2O2, an ROS promoter. Our results provide the first indication that KM exerts an inhibitory effect on NLRP3 inflammasome activation associated with blocking the ROS/NF-κB/NLRP3 signal axis. KM might have potential clinical application in the treatment of NLRP3 inflammasome-related diseases.
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State-of-the-art methods assessing pathogenic non-coding variants have mostly been characterized on common disease-associated polymorphisms, yet with modest accuracy and strong positional biases. In this study, we curated 737 high-confidence pathogenic non-coding variants associated with monogenic Mendelian diseases. In addition to interspecies conservation, a comprehensive set of recent and ongoing purifying selection signals in humans is explored, accounting for lineage-specific regulatory elements. Supervised learning using gradient tree boosting on such features achieves a high predictive performance and overcomes positional bias. NCBoost performs consistently across diverse learning and independent testing data sets and outperforms other existing reference methods.
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ADN Intergénico/genética , Enfermedades Genéticas Congénitas/genética , Polimorfismo de Nucleótido Simple , Selección Genética , Aprendizaje Automático Supervisado , Humanos , Secuenciación Completa del GenomaRESUMEN
NF-κB mediates acquired resistance in acute myeloid leukemia (AML) cells treated with DNA-damaging agents. Because DNA repair is the major molecular shift that alters sensitivity to DNA-damaging agents, we explored whether activation of the NF-κB pathway promotes AML cell survival by regulating DNA repair after chemotherapy. Our results showed that RELA, an important subunit of NF-κB, regulated DNA repair by binding to the promoter region of the PARP1 gene and affecting PARP1 gene transcription. Conversely, PARP1 knockdown reduced NF-κB activity, indicating that NF-κB and PARP1 create a positive feedback loop in DNA repair. Simultaneous treatment with the NF-κB inhibitor BMS-345541 and the PARP1 inhibitor olaparib resulted in robust killing of AML cells. This dual inhibition significantly suppressed tumor growth and extended survival times in xenograft tumor models. IMPLICATIONS: RELA and PARP1 form a positive feedback loop to regulate DNA damage repair, simultaneous inhibition of NF-κB and PARP1 increases the antileukemic efficacy of daunorubicin in vitro and in vivo, broadening the use of PARP1 inhibitors.