RESUMO
Gout and hyperuricemia are metabolic diseases characterized with high serum uric acid (SUA) levels that significantly impact human health. Lesinurad, a uricosuric agent, is limited to concurrent use with xanthine oxidase inhibitors (XOIs) in clinical practice due to its restricted efficacy and potential nephrotoxicity. Herein, extensive structural modifications of lesinurad were conducted through scaffold hopping and substituent modification strategies, affording 54 novel derivatives containing pyrimidine-fused cyclic structures. Notably, the thienopyrimidine compound 29 demonstrated a remarkable 2-fold increase in SUA-lowering in vivo activity compared to lesinurad, while exhibiting potent inhibitory activity against the urate transporter 1 (URAT1, IC50 = 2.01 µM) and glucose transporter 9 (GLUT9, IC50 = 18.21 µM). Furthermore, it possessed a lower effective dosage of 0.5 mg/kg, favorable safety profile without any apparent acute toxicity at doses of 1000 mg/kg, and improved pharmacokinetic properties. Overall, we have discovered an efficacious URAT1/GLUT9 dual inhibitor for inhibiting urate reabsorption with favorable pharmacokinetic profiles.
Assuntos
Gota , Hiperuricemia , Transportadores de Ânions Orgânicos , Tioglicolatos , Triazóis , Humanos , Ácido Úrico/uso terapêutico , Gota/tratamento farmacológico , Hiperuricemia/tratamento farmacológico , Uricosúricos/uso terapêutico , Pirimidinas/toxicidade , Pirimidinas/uso terapêutico , Proteínas Facilitadoras de Transporte de Glucose , Proteínas de Transporte de Cátions OrgânicosRESUMO
Urate Transporter 1 (URAT1) plays a crucial role in uric acid transport, making it an attractive target for the treatment of gout and hyperuricemia. As a representative URAT1 inhibitor, Lesinurad treat gout by promoting the uric acid excretion. However, its lower in vitro and in vivo activity should be highly attracted attention. Herein, the bioisosterism, molecular hybridization and scaffold hopping strategies were exploited to modify all the structural components of Lesinurad and finally thirty novel compounds bearing thienopyrimidinone or pyridine core were obtained. Most of the compounds displayed certain URAT1 inhibitory activity in vitro. Among them, thienopyrimidinones 6 (IC50 = 7.68 µM), 10 (IC50 = 7.56 µM), 14 (IC50 = 7.31 µM) and 15 (IC50 = 7.90 µM) showed slightly better potency than positive control Lesinurad (IC50 = 9.38 µM). Notably, 10 also displayed inhibitory activity (IC50 = 55.96 µM) against GLUT9. Additionally, in vivo serum uric acid (SUA)-lowering experiments were performed on some representative compounds and it was revealed that all the selected compounds could decrease the SUA level in mice, of which the decrease rate of SUA was 73.29% for the most promising compound 10, significantly greater than that of Lesinurad (26.89%). Meanwhile, the preliminary SARs based on the URAT1 inhibitory activity were discussed in detail, which pointed out the direction for further structural optimization. Overall, the thienopyrimidinone and pyridine are prospective skeletons for the developing novel URAT1 inhibitors with considerable potential for optimization.
Assuntos
Gota , Hiperuricemia , Transportadores de Ânions Orgânicos , Animais , Humanos , Camundongos , Proteínas de Transporte de Cátions Orgânicos , Estudos Prospectivos , Piridinas/farmacologia , Ácido ÚricoRESUMO
Leaf anatomical traits play key roles in plant functions and display evolutionary adaptive changes to suit the surrounding environment. To reveal the adaptive mode and mechanisms of plants in response to global warming, we analyzed leaf morphology and anatomical structures in three different species, Epilobium amurense Hausskn., Pedicularis densispica Franch., and Potentilla fulgens Wall. ex Hook., growing along an elevational gradient (3,000-4,600 m) in the Yulong Mountains. The results showed leaf length and width decreased, whereas leaf thickness increased with increasing altitude in all three species. Thickness of leaf upper epidermis, lower epidermis, palisade and spongy mesophyll, and main vein increased with rising altitude. Stomatal density in each species increased with rising elevation. These results illustrate that plants can adapt to the environmental changes that accompany high altitudes by decreasing leaf area and increasing leaf thickness, mesophyll tissue thickness, and stomatal density. Such morphological and anatomical plasticity would lead to lower transpiration rates, enhanced internal temperature and water status, and improved photosynthetic capability.
RESUMO
High-altitude mountains are often geographic barriers to gene flow and play important roles in shaping population divergence. The central Qinghai-Tibetan Plateau (QTP) stands the location of the Tanggula Mountains (TM). We use the TM as a case, using Carex moorcroftii, a dominant species on the QTP to test the effects of geographic barriers on plant population divergence. We sampled 18 C. moorcroftii populations along a north-south transect crossing the TM to investigate the correlations of genetic variation and morphological traits with climate variables. The results showed this species holds high genetic diversity (He = 0.58) and the surveyed populations can be genetically clustered into two groups: populations from the north face of TM, and the other from the south. Gene flow between populations within groups is higher than those between groups. The traits, number and mass of seeds, mass of root and infructescence significantly varied among populations. Mantel-tests detected a weak but significantly positive correlation between genetic and geographic (R2 = 0.107, p = 0.032) and climatic distance (R2 = 0.162, p = 0.005), indicating both isolation by distance and isolation by environment. These findings together suggest high-altitude mountains of TM interrupt habitat continuity, result in distinct climatic conditions on both sides, increasing population divergence of plant species.
RESUMO
Estimating the potential of species to cope with rapid environmental climatic modifications is of vital importance for determining their future viability and conservation. The variation between existing populations along a climatic gradient may predict how a species will respond to future climate change. Stipa purpurea is a dominant grass species in the alpine steppe and meadow of the Qinghai-Tibetan Plateau (QTP). Ecological niche modelling was applied to S. purpurea, and its distribution was found to be most strongly correlated with the annual precipitation and the mean temperature of the warmest quarter. We established a north-to-south transect over 2000 km long on the QTP reflecting the gradients of temperature and precipitation, and then we estimated the morphological by sampling fruited tussocks and genetic divergence by using 11 microsatellite markers between 20 populations along the transect. Reproductive traits (the number of seeds and reproductive shoots), the reproductive-vegetative growth ratio and the length of roots in the S. purpurea populations varied significantly with climate variables. S. purpurea has high genetic diversity (He = 0.585), a large effective population size (Ne >1,000), and a considerable level of gene flow between populations. The S. purpurea populations have a mosaic genetic structure: some distant populations (over 1000 km apart) clustered genetically, whereas closer populations (< 100 km apart) had diverged significantly, suggesting local adaptation. Asymmetrical long-distance inter-population gene flow occurs along the sampling transect and might be mediated by seed dispersal via migratory herbivores, such as the chiru (Pantholops hodgsonii). These findings suggest that population performance variation and gene flow both facilitate the response of S. purpurea to climate change.
Assuntos
DNA de Plantas/genética , Variação Genética , Poaceae/fisiologia , Adaptação Biológica , Mudança Climática , Fluxo Gênico , Repetições de Microssatélites , Modelos Teóricos , Poaceae/genética , Densidade Demográfica , TibetRESUMO
Recently, the frequent seasonal drought in Southwest China has brought considerable concerns and continuous heated arguments on the "water pump" viewpoint (i.e., the water demand from Hevea spp. and Eucalyptus spp. can be treated as a water pump) once again. However, such viewpoint just focused on water consumption from vegetation transpiration and its ecoenvironment impacts, which had not considered other attributes of vegetation, namely, water saving and drought resistance, and hydrological regulation (water conservation) into consideration. Thus, in this paper, the synthesized attributes of regional vegetation water use had been mainly discussed. The results showed that the study on such aspects as the characters of water consumption from vegetation transpiration, the potential of water saving and drought resistance, and the effects of hydrological regulation in Southwest China lagged far behind, let alone the report on synthesized attributes of water utilization with the organic combination of the three aspects above or the paralleled analysis. Accordingly, in this paper, the study on the synthesized attributes of water use by regional vegetation in Southwest China was suggested, and the objectives of such a special study were clarified, targeting the following aspects: (i) characters of water consumption from transpiration of regional typical artificial vegetation; (ii) potential of water saving and drought resistance of regional typical artificial vegetation; (iii) effects of hydrological regulation of regional typical artificial vegetation; (iv) synthesized attributes of water use by regional typical artificial vegetation. It is expected to provide a new idea for the scientific assessment on the regional vegetation ecoenvironment effects and theoretical guidance for the regional vegetation reconstruction and ecological restoration.