Recent Submissions

  • Plastid phylogenomics resolves ambiguous relationships within the orchid family and provides a solid timeframe for biogeography and macroevolution

    Serna-Sánchez, Maria Alejandra; Pérez-Escobar, Oscar A.; Bogarín, Diego; Torres-Jimenez, María Fernanda; Alvarez-Yela, Astrid Catalina; Arcila-Galvis, Juliana E.; Hall, Climbie F.; de Barros, Fábio; Pinheiro, Fábio; Dodsworth, Steven; et al. (SpringerNature, 2021-03-25)
    Recent phylogenomic analyses based on the maternally inherited plastid organelle have enlightened evolutionary relationships between the subfamilies of Orchidaceae and most of the tribes. However, uncertainty remains within several subtribes and genera for which phylogenetic relationships have not ever been tested in a phylogenomic context. To address these knowledge-gaps, we here provide the most extensively sampled analysis of the orchid family to date, based on 78 plastid coding genes representing 264 species, 117 genera, 18 tribes and 28 subtribes. Divergence times are also provided as inferred from strict and relaxed molecular clocks and birth-death tree models. Our taxon sampling includes 51 newly sequenced plastid genomes produced by a genome skimming approach. We focus our sampling efforts on previously unplaced clades within tribes Cymbidieae and Epidendreae. Our results confirmed phylogenetic relationships in Orchidaceae as recovered in previous studies, most of which were recovered with maximum support (209 of the 262 tree branches). We provide for the first time a clear phylogenetic placement for Codonorchideae within subfamily Orchidoideae, and Podochilieae and Collabieae within subfamily Epidendroideae. We also identify relationships that have been persistently problematic across multiple studies, regardless of the different details of sampling and genomic datasets used for phylogenetic reconstructions. Our study provides an expanded, robust temporal phylogenomic framework of the Orchidaceae that paves the way for biogeographical and macroevolutionary studies.
  • Extensive plastid-nuclear discordance in a recent radiation of Nicotiana section Suaveolentes (Solanaceae)

    Dodsworth, Steven; Christenhusz, Maarten J.M.; Conran, John G.; Guignard, Maite S.; Knapp, Sandra; Struebig, Monika; Leitch, Andrew R.; Chase, Mark W. (Oxford University Press, 2020-05-24)
    Nicotiana section Suaveolentes is the largest section of Nicotiana and is a monophyletic group of allotetraploid species. Most of the species are endemic to Australia, but three species occur on islands in the South Pacific as far east as French Polynesia and one species is native to Namibia. Here, we present phylogenetic results based on genome skimming, with near-complete taxon sampling and multiple accessions sampled for several species. These represent the first phylogenetic results for the section that include most recognized taxa, using wild-sourced material wherever possible. Despite known chromosome number and genome size changes in the section, there is little divergence in the ribosomal DNA operon (26S, 18.S and 5.8S plus associated spacers) and plastid genomes, with little to no taxonomic signal in plastome phylogenetic results and clear plastid-nuclear discordance. These results contrast with strong morphological differentiation (both floral and vegetative) between most of the core Australian taxa and obvious differences in ecological preferences. Together, these initial results portray Nicotiana section Suaveolentes as experiencing recent and ongoing radiation in the arid zone of Australia.
  • Liqui-pellet: the emerging next-generation oral dosage form which stems from liquisolid concept in combination with pelletization technology

    Lam, Matthew; Ghafourian, Taravat; Nokhodchi, Ali (Springer New York LLC, 2019-06-24)
    In spite of the major advantages that the liquisolid technology offers, particularly in tackling poor bioavailability of poorly water-soluble drugs (i.e., BCS Class II drugs), there are a few critical drawbacks. The inability of a high liquid load factor, poor flowability, poor compactibility, and an inability to produce a high dose dosage form of a reasonable size for swallowing are major hurdles, hampering this technology from being commercially feasible. An attempt was therefore made to overcome these drawbacks whilst maintaining the liquisolid inherent advantages. This resulted in the emerging next generation of oral dosage forms called the liqui-pellet. All formulations were incorporated into capsules as the final product. Solubility studies of naproxen were conducted in different liquid vehicles, namely polyethylene glycol 200, propylene glycol, Tween 80, Labrafil, Labrasol, and Kolliphor EL. The scanning electron microscopy studies indicated that the liquid vehicle tends to reduce the surface roughness of the pellet. X-ray powder diffraction (XRPD) indicated no significant differences in the crystalline structure or amorphous content between the physical mixture and the liqui-pellet formulation. This was due to the presence of a high concentration of amorphous Avicel in the formulation which overshadowed the crystalline structure of naproxen in the physical mixtures. Flowability and dissolution tests confirmed that this next-generation oral dosage form has excellent flowability, whilst maintaining the typical liquisolid enhanced drug release performance in comparison to its physical mixture counterpart. The liqui-pellet also had a high liquid load factor of 1, where ~ 29% of the total mass was the liquid vehicle. This shows that a high liquid load factor can be achieved in a liqui-pellet without compromising flowability. Overall, the results showed that the poor flowability of a liquisolid formulation could be overcomed with the liqui-pellet, which is believed to be a major advancement into the commercial feasibility of the liquisolid concept.
  • Optimising the release rate of naproxen liqui-pellet: a new technology for emerging novel oral dosage form

    Lam, Matthew; Ghafourian, Taravat; Nokhodchi, Ali; (Springer, 2019-07-08)
    Liqui-pellet is a new dosage form stemming from pelletisation technology and concept from liquisolid technology. In spite of liqui-pellet overcoming a major hurdle in liquisolid technology through achieving excellent flow property with high liquid load factor, the formulation requires to be optimised in order to improve drug release rate. Liqui-pellets of naproxen containing Tween 80, Primojel, Avicel and Aerosil were extruded and spheronised. Flowability test confirmed that all liqui-pellet formulations have excellent-good flow property (Carr’s index between 3.9–11.17%), including liqui-pellets with a high liquid load factor of 1.52, where 38% of the total mass is co-solvent. This shows a relatively high liquid load factor can be achieved in liqui-pellet without compromising the flowability, which is one of the key novelty of this work. It was found that the improved drug release rate was due to the remarkably improved disintegration of the supposedly non-disintegrating microcrystalline-based pellet; the optimised liqui-pellet seems to explode into fragments in the dissolution medium. At pH 1.2, the optimised formulation had ~ 10% more drug release than non-optimised formulation after 2 h, and at pH 7.4, the drug release of the optimised pellet was nearing 100% at ~ 15 min, whereas the none-optimised pellet only achieved ~ 79% drug release after 2 h. DSC and XRPD indicated an increase in the dissolution rate could be due to molecularly dispersion of naproxen in the pellets. Overall results showed that liqui-pellet exhibited an enhanced drug release and the capacity for high liquid load factor whilst maintaining excellent flowability, rendering it a potentially commercially feasible drug delivery system.
  • Critical role of the maternal immune system in the pathogenesis of autism spectrum disorder

    Ravaccia, Davide; Ghafourian, Taravat; University of Sussex (MDPI AG, 2020-12-01)
    Autism spectrum disorders (ASD) are a group of neurodevelopmental disorders characterised by impairments in communication, social interaction, and the presence of restrictive and repetitive behaviours. Over the past decade, most of the research in ASD has focused on the contribution of genetics, with the identification of a variety of different genes and mutations. However, the vast heterogeneity in clinical presentations associated with this disorder suggests that environmental factors may be involved, acting as a “second hit” in already genetically susceptible individuals. To this regard, emerging evidence points towards a role for maternal immune system dysfunctions. This literature review considered evidence from epidemiological studies and aimed to discuss the pathological relevance of the maternal immune system in ASD by looking at the proposed mechanisms by which it alters the prenatal environment. In particular, this review focuses on the effects of maternal immune activation (MIA) by looking at foetal brain-reactive antibodies, cytokines and the microbiome. Despite the arguments presented here that strongly implicate MIA in the pathophysiology of ASD, further research is needed to fully understand the precise mechanisms by which they alter brain structure and behaviour. Overall, this review has not only shown the importance of the maternal immune system as a risk factor for ASD, but more importantly, has highlighted new promising pathways to target for the discovery of novel therapeutic interventions for the treatment of such a life-changing disorder.
  • QSAR and molecular docking for the search of AOX inhibitors: a rational drug discovery approach

    Rosell-Hidalgo, Alicia; Young, Luke; Moore, Anthony L.; Ghafourian, Taravat; University of Sussex; University of Bedfordshire (Springer Science and Business Media Deutschland GmbH, 2020-12-08)
    The alternative oxidase (AOX) is a monotopic diiron carboxylate protein that catalyses the oxidation of ubiquinol and the reduction of oxygen to water. Although a number of AOX inhibitors have been discovered, little is still known about the ligand–protein interaction and essential chemical characteristics of compounds required for a potent inhibition. Furthermore, owing to the rapidly growing resistance to existing inhibitors, new compounds with improved potency and pharmacokinetic properties are urgently required. In this study we used two computational approaches, ligand–protein docking and Quantitative Structure–Activity Relationships (QSAR) to investigate binding of AOX inhibitors to the enzyme and the molecular characteristics required for inhibition. Docking studies followed by protein–ligand interaction fingerprint (PLIF) analysis using the AOX enzyme and the mutated analogues revealed the importance of the residues Leu 122, Arg 118 and Thr 219 within the hydrophobic cavity. QSAR analysis, using stepwise regression analysis with experimentally obtained IC50 values as the response variable, resulted in a multiple regression model with a good prediction accuracy. The model highlighted the importance of the presence of hydrogen bonding acceptor groups on specific positions of the aromatic ring of ascofuranone derivatives, acidity of the compounds, and a large linker group on the compounds on the inhibitory effect of AOX.
  • Genome sequence of the biocontrol agent coniothyrium minitans conio (IMI 134523)

    Patel, Denise; Shittu, Taiwo Adewale; Baroncelli, Riccardo; Muthumeenakshi, Sreenivasaprasad; Osborne, Thomas H.; Janganan, Thamarai K.; Sreenivasaprasad, Surapareddy; University of Bedfordshire (American Phytopathological Society, 2021-02-16)
    Coniothyrium minitans (synonym, Paraphaeosphaeria minitans) is a highly specific mycoparasite of the wide host range crop pathogen Sclerotinia sclerotiorum. The capability of C. minitans to destroy the sclerotia of S. sclerotiorum has been well recognized and it is available as a widely used biocontrol product Contans WG. We present the draft genome sequence of C. minitans Conio (IMI 134523), which has previously been used in extensive studies that formed part of a registration package of the commercial product. This work provides a distinctive resource for further research into the molecular basis of mycoparasitism to harness the biocontrol potential of C. minitans.
  • Migration of BEAS-2B cells enhanced by H1299 cell derived-exosomes

    Wang, Shuwei; Ju, Tuoyu; Wang, Jiajia; Yang, Fan; Qu, Kaige; Liu, Wei; Wang, Zuobin; Jilin University; Changchun University of Science and Technology; University of Bedfordshire (Elsevier Ltd, 2021-01-12)
    Previous studies reported that exosomes (Exos) secreted by tumor cells could affect the tumor cells themselves and normal cells. However, the effects of exosomes derived from tumor cells on normal cells’ migration and mechanical characteristics are rarely reported. This work explores the effects of H1299 cell-derived exosomes (H1299-Exos) on the migration of BEAS-2B cells, and analyzes possible mechanical mechanisms. In the experiments, exosomes were isolated from the culture supernatants of H1299 cells by ultracentrifugation. The H1299-Exos were confirmed by scanning electron microscope (SEM) and western blotting (WB). The BEAS-2B cell migration was assessed using scratch assays. Cytoskeletal structure changes were detected by immunofluorescence. Surface morphology and mechanical properties were measured by atomic force microscopy (AFM). After incubation with H1299-Exos for 48 h, BEAS-2B cells enhanced migration ability, with increased filopodia and cytoskeletal rearrangements. The changes in the morphology and mechanical properties of the cells caused by H1299-Exos were detected using AFM, including the increase in cell length and the decrease in cell height, Young's modulus and adhesion. In short, H1299-Exos promoted the BEAS-2B cell migrations. It indicates that the morphological and mechanical properties can be used as a means to assess normal cell alterations induced by tumor cell derived-exosomes. This provides a method for studying the effects of exosomes secreted by tumor cells on normal cells and the changes in their physical properties.
  • Combination of Sanger and target-enrichment markers supports revised generic delimitation in the problematic ‘Urera clade’ of the nettle family (Urticaceae)

    Wells, Tom; Maurin, Olivier; Dodsworth, Steven; Friis, Ib; Cowan, Robyn S.; Epitawalage, Niroshini; Brewer, Grace E.; Forest, Felix; Baker, William; Monro, Alexandre; et al. (Elsevier, 2020-11-05)
    Urera Gaudich, s.l. is a pantropical genus comprising c. 35 species of trees, shrubs, and vines. It has a long history of taxonomic uncertainty, and is repeatedly recovered as polyphyletic within a poorly resolved complex of genera in the Urticeae tribe of the nettle family (Urticaceae). To provide generic delimitations concordant with evolutionary history, we use increased taxonomic and genomic sampling to investigate phylogenetic relationships among Urera and associated genera. A cost-effective two-tier genome-sampling approach provides good phylogenetic resolution by using (i) a taxon-dense sample of Sanger sequence data from two barcoding regions to recover clades of putative generic rank, and (ii) a genome-dense sample of target-enrichment data for a subset of representative species from each well-supported clade to resolve relationships among them. The results confirm the polyphyly of Urera s.l. with respect to the morphologically distinct genera Obetia, Poikilospermum and Touchardia. Afrotropic members of Urera s.l. are recovered in a clade sister to the xerophytic African shrubs Obetia; and Hawaiian ones with Touchardia, also from Hawaii. Combined with distinctive morphological differences between Neotropical and African members of Urera s.l., these results lead us to resurrect the previously synonymised name Scepocarpus Wedd. for the latter. The new species epiphet Touchardia oahuensis T.Wells & A.K. Monro is offered as a replacement name for Touchardia glabra non H.St.John, and subgenera are created within Urera s.s. to account for the two morphologically distinct Neotropical clades. This new classification minimises taxonomic and nomenclatural disruption, while more accurately reflecting evolutionary relationships within the group.
  • Extreme climate response to marine cloud brightening in the arid Sahara-Sahel-Arabian Peninsula zone

    Zhu, Yuanzhuo; Zhang, Zhihua; Crabbe, M. James C.; Shandong University; Beijing Normal University; Oxford University; University of Bedfordshire; Shanxi University (Emerald, 2021-02-08)
    Purpose Climatic extreme events are predicted to occur more frequently and intensely and will significantly threat the living of residents in arid and semi-arid regions. Therefore, this study aims to assess climatic extremes’ response to the emerging climate change mitigation strategy using a marine cloud brightening (MCB) scheme. Design/methodology/approach Based on Hadley Centre Global Environmental Model version 2-Earth System model simulations of a MCB scheme, this study used six climatic extreme indices [i.e. the hottest days (TXx), the coolest nights (TNn), the warm spell duration (WSDI), the cold spell duration (CSDI), the consecutive dry days (CDD) and wettest consecutive five days (RX5day)] to analyze spatiotemporal evolution of climate extreme events in the arid Sahara-Sahel-Arabian Peninsula Zone with and without MCB implementation. Findings Compared with a Representative Concentration Pathways 4.5 scenario, from 2030 to 2059, implementation of MCB is predicted to decrease the mean annual TXx and TNn indices by 0.4–1.7 and 0.3–2.1°C, respectively, for most of the Sahara-Sahel-Arabian Peninsula zone. It would also shorten the mean annual WSDI index by 118–183 days and the mean annual CSDI index by only 1–3 days, especially in the southern Sahara-Sahel-Arabian Peninsula zone. In terms of extreme precipitation, MCB could also decrease the mean annual CDD index by 5–25 days in the whole Sahara and Sahel belt and increase the mean annual RX5day index by approximately 10 mm in the east part of the Sahel belt during 2030–2059. Originality/value The results provide the first insights into the impacts of MCB on extreme climate in the arid Sahara-Sahel-Arabian Peninsula zone.
  • COVID-19 in Wuhan, China: pressing realities and city management

    Li, Rita Yi Man; Yue, Xiao-Guang; Crabbe, M. James C.; Hong Kong Shue Yan University; European University of Cyprus; Oxford University; University of Bedfordshire; Shanxi University (Frontiers, 2021-02-17)
    To most economists around the World, Covid-19 has provided an objective lesson in market failure. In the absence of complete information and sometimes even fake news, nobody knew what kind of pandemic it was at the beginning. Yet, there were 32,583 patients with laboratory-confirmed Covid-19 in Wuhan between December 8, 2019, and 8 March 8, 2020. The pandemic crippled and continues to cripple many health systems and has created unprecedented pressure on the psychological and physical aspects of millions of people's lives around the world. Over 200 countries and territories suffer from an acute shortage of medical personnel and medical equipment. The responses of different countries to Covid-19 has involved a range of measures that reflect national values, politics, and variations in scientific advice provided by local experts. Political considerations have often become more important than science. The Covid-19 outbreak in Wuhan was one of the most serious cases amongst all cities in the world, yet Wuhan managed and gain control of this pandemic. Health care systems and policies are important aspects that affect the control of infectious diseases like Covid-19. In China, 98% of primary health-care is complemented by traditional Chinese medicine (TCM) with allopathic approaches. Previous research has found that the cure rate increased by 33% among mild cases after adopting TCM with allopathic approaches. The hospital stay of severe patients with TCM's and nucleic acid turning negative was shortened by over 2 days. Prior to Covid-19, the government's Healthy China 2030 plan was already addressing chronic diseases in the aging population by raising healthcare expenditure. This is in sharp contrast to other countries with aging population problems such as Italy, where the government cut the healthcare budget substantially after the economic downturn. Hospital bed allocation went down from a maximum of four for every thousand inhabitants to a maximum of 3.7, despite the fact that 23.1% of the Italian population were aged 65 years and older in 2020. Likewise, the post-2008 financial crisis in Spain forced severe cuts to healthcare costs, which caused pressure on the system when there was an increase in demand for healthcare services. These measures particularly affected the elderly and disabled who are more vulnerable to Covid-19. Healthcare costs become underfunded at the level of 6.4% of GDP. Apart from scientific evidence on the effectiveness of TCM in curing covid, financial expenditures on health care is an important distal factor that helped Wuhan overcome Covid-19 quickly. In the following sections of this paper, we review the three city management stages adopted in Wuhan, to study proximal causes of success in combating the virus: (1) strong government intervention early in the outbreak; (2) the city lockdown; and, (3) the use of digital measures, such as a health code, when the city reopened.
  • MicroRNAs for virus pathogenicity and host responses, identified in SARS-CoV-2 genomes, may play roles in viral-host co-evolution in putative zoonotic host species

    Lange, Sigrun; Arisan, Elif Damla; Grant, Guy H.; Uysal-Onganer, Pinar; University of Westminster; Gebze Technical University; University of Bedfordshire (MDPI, 2021-01-16)
    Our recent study identified seven key microRNAs (miR-8066, 5197, 3611, 3934-3p, 1307-3p, 3691-3p, 1468-5p) similar between SARS-CoV-2 and the human genome, pointing at miR-related mechanisms in viral entry and the regulatory effects on host immunity. To identify the putative roles of these miRs in zoonosis, we assessed their conservation, compared with humans, in some key wild and domestic animal carriers of zoonotic viruses, including bat, pangolin, pig, cow, rat, and chicken. Out of the seven miRs under study, miR-3611 was the most strongly conserved across all species; miR-5197 was the most conserved in pangolin, pig, cow, bat, and rat; miR-1307 was most strongly conserved in pangolin, pig, cow, bat, and human; miR-3691-3p in pangolin, cow, and human; miR-3934-3p in pig and cow, followed by pangolin and bat; miR-1468 was most conserved in pangolin, pig, and bat; while miR-8066 was most conserved in pangolin and pig. In humans, miR-3611 and miR-1307 were most conserved, while miR-8066, miR-5197, miR-3334-3p and miR-1468 were least conserved, compared with pangolin, pig, cow, and bat. Furthermore, we identified that changes in the miR-5197 nucleotides between pangolin and human can generate three new miRs, with differing tissue distribution in the brain, lung, intestines, lymph nodes, and muscle, and with different downstream regulatory effects on KEGG pathways. This may be of considerable importance as miR-5197 is localized in the spike protein transcript area of the SARS-CoV-2 genome. Our findings may indicate roles for these miRs in viral-host co-evolution in zoonotic hosts, particularly highlighting pangolin, bat, cow, and pig as putative zoonotic carriers, while highlighting the miRs' roles in KEGG pathways linked to viral pathogenicity and host responses in humans. This in silico study paves the way for investigations into the roles of miRs in zoonotic disease.
  • Targeted editing of SlMAPK6 using CRISPR/Cas9 technology to promote the development of axillary buds in tomato plants

    Li, Yunzhou; Yue, Ningbo; Basit, Abdul; Li, Yulong; Zhang, Dalong; Qin, Lei; Crabbe, M. James C.; Xu, Wen; Wang, Yong; Yan, Jianmin; et al. (Canadian Center of Science and Education, 2021-01-15)
    The mitogen-activated protein kinase (MAPK) cascade signaling system has been relatively conserved throughout the evolution of eukaryotes and is involved in the regulation of growth and development and metabolism. In this study, dwarf tomato plants were used as the research material. First, the tissue-specific expression of SlMAPK6 was measured in wild-type plants by quantitative RT-PCR. The results showed that SlMAPK6 was highly expressed in the tissues of the stems, leaves and flowers but was expressed at low levels in the tissues of the roots, sepals and fruits. Second, SlMAPK6-knockout lines CRISPR-3 and CRISPR-7 were obtained by CRISPR-Cas9 technology and Agrobacterium-mediated transformation. Compared with wild-type, the mutant lines CRISPR-3 and CRISPR-7 showed significant phenotypic characteristics, such as increased numbers of axillary buds and true leaves, thickened stems, and longer leaflets. In addition, to explore the molecular mechanism by which MAPK regulates axillary bud growth, we also showed that SlMAPK6 positively regulates the strigolactone synthesis genes SlCCD7 and SlCCD8 and the gibberellin (GA) synthesis genes GA20ox3 and GA3ox1 and negatively regulates the axillary bud development-related genes Ls, BL and BRC1b/TCP8 and the GA synthesis inhibitory gene GAI. Therefore, SlMAPK6 appears to regulate the synthesis of strigolactone and GA to induce the growth and development of tomato axillary buds.
  • Bovine milk fat globule epidermal growth factor Ⅷ activates PI3K/Akt signaling pathway and attenuates sarcopenia in rat model induced by D-galactose

    Li, He; Wang, Rongchun; Wang, Lifeng; Li, Lin; Ma, Ying; Zhou, Shaobo; Jiangsu Normal University; Harbin Institute of Technology; Northeast Agriculture University; University of Bedfordshire (Elsevier, 2020-12-17)
    To develop a more effective and safer treatment for sarcopenia, this research investigated the anti-sarcopenia mechanism of Milk Fat Globule Epidermal Growth Factor Ⅷ (MFG-E8) from the liver function and metabolism in sarcopenic model rat. After 4 weeks nutritional intervention experiment, MFG-E8 can significantly increase the gastrocnemius mass in rat. The mechanism of MFG-E8 in improving sarcopenia was related to its promotional capacity to the activities of superoxide dismutase (SOD) activity in serum, Glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) in liver. Meanwhile, MFG-E8 could also down-regulate obesity-related indicators, such as triglyceride (TG) and Non-esterified fatty acid (NEFA). The analysis of liver and gastrocnemius histopathology found that MFG-E8 could reduce the accumulation of fatty vesicles, improve liver function, thereby alleviating gastrocnemius tissue inflammation. In vitro experiments, myoblasts obtained from gastrocnemius tissue showed that MFG-E8 could reduce mitochondrial autophagy and inhibit cell apoptosis. In addition, MFG-E8 could up-regulate the phosphorylation level of PI3K via activating PI3K/Akt signaling pathway in gastrocnemius tissue, and promote the formation of muscle fibers, thereby increasing muscle mass. Moreover, MFG-E8 could also promote the formation of neuromuscular junctions by up-regulating the mRNA and protein expression of MusK in gastrocnemius.
  • Effect and mechanism of Ganoderma lucidum spores on alleviation diabetic cardiomyopathy in a pilot in vivo study

    Shaher, Fahmi; Wang, Shuqiu; Qiu, Hong-Bin; Hu, Yu; Zhang, Yu; Wang, Weiqun; AL-ward, Hisham; Abdulghani, Mahfoudh A. M.; Baldi, Salem; Zhou, Shaobo; et al. (Dove Press, 2020-12-07)
    Background: Ganoderma lucidum spores (GLS) exhibit disease prevention properties, but no study has been carried out on the anti-diabetic cardiomyopathy property of GLS. The aim of this study is to evaluate the hyperglycemia-mediated cardiomyopathy protection and mechanisms of GLS in diabetic rats induced by streptozotocin (STZ). Methods: Male SD rats were randomly divided into three groups. Two groups were given STZ (50 mg/kg, i.p.) treatment and when their fasting plasma glucose was above 16.7 mmol/L, one group was given placebo, as diabetic group; and another group was given GLS (300 mg/kg) treatment. The group without STZ treatment was given placebo as a control group. The experiment lasted 70 days. The histology of myocardium and biomarkers of antioxidant, myocardial injury, pro-inflammatory cytokines, pro-apoptotic proteins and phosphorylation of key proteins in PI3K/AKT pathway were assessed. Results: Biochemical analysis showed that GLS treatment significantly reduced the blood glucose (-20.3%) and triglyceride (-20.4%) levels compared to diabetic group without treatment. GLS treatment decreased the content of MDA (-25.6%) and activity of lactate dehydrogenase (-18.9%) but increased the activity of GSH-Px (65.4%). Western blot analysis showed that GLS treatment reduced the expression of both alpha-smooth muscle actin and brain natriuretic peptide. Histological analysis on the cardiac tissue micrographs showed that GLS treatment reduced the collagen fibroses and glycogen reactivity in myocardium. Both western blot and immunohistochemistry analyses showed that GLS treatment decreased the expression levels of pro-inflammatory factors (cytokines IL-1β, and TNF-α) as well as apoptosis regulatory proteins (Bax, caspase-3 and -9), but increased the Bcl-2. Moreover, GLS treatment significantly increased the phosphorylation of key proteins involved in PI3K/AKT pathway, e.g. p-AKT p-PI3K and mTOR. Conclusion: The results indicated that GLS treatment alleviates diabetic cardiomyopathy by reducing hyperglycemia, oxidative stress, inflammation, apoptosis and further attenuating the fibrosis and myocardial dysfunction induced by STZ through the stimulation of the PI3K/Akt/mTOR signaling pathway.
  • Lamellipodin promotes invasive 3D cancer cell migration via regulated interactions with Ena/VASP and SCAR/WAVE

    Carmona, G.; Perera, U.; Gillett, C.; Naba, A.; Law, Ah-Lai; Sharma, V.P.; Wang, J.; Wyckoff, J.; Balsamo, M.; Mosis, F.; et al. (Nature Publishing Group, 2016-03-21)
    Cancer invasion is a hallmark of metastasis. The mesenchymal mode of cancer cell invasion is mediated by elongated membrane protrusions driven by the assembly of branched F-actin networks. How deregulation of actin regulators promotes cancer cell invasion is still enigmatic. We report that increased expression and membrane localization of the actin regulator Lamellipodin correlate with reduced metastasis-free survival and poor prognosis in breast cancer patients. In agreement, we find that Lamellipodin depletion reduced lung metastasis in an orthotopic mouse breast cancer model. Invasive 3D cancer cell migration as well as invadopodia formation and matrix degradation was impaired upon Lamellipodin depletion. Mechanistically, we show that Lamellipodin promotes invasive 3D cancer cell migration via both actin-elongating Ena/VASP proteins and the Scar/WAVE complex, which stimulates actin branching. In contrast, Lamellipodin interaction with Scar/WAVE but not with Ena/VASP is required for random 2D cell migration. We identified a phosphorylation-dependent mechanism that regulates selective recruitment of these effectors to Lamellipodin: Abl-mediated Lamellipodin phosphorylation promotes its association with both Scar/WAVE and Ena/VASP, whereas Src-dependent phosphorylation enhances binding to Scar/WAVE but not to Ena/VASP. Through these selective, regulated interactions Lamellipodin mediates directional sensing of epidermal growth factor (EGF) gradients and invasive 3D migration of breast cancer cells. Our findings imply that increased Lamellipodin levels enhance Ena/VASP and Scar/WAVE activities at the plasma membrane to promote 3D invasion and metastasis.
  • Cleavage of mer tyrosine kinase (MerTK) from the cell surface contributes to the regulation of retinal phagocytosis

    Law, Ah-Lai; Parinot, Celia; Chatagnon, Jonathan; Gravez, Basile; Sahel, Jose-Alain; Bhattacharya, Shomi S.; Nandrot, Emeline F.; ; Sorbonne Universite; University College London; et al. (American Society for Biochemistry and Molecular Biology Inc., 2014-12-23)
    Background: The MerTK receptor is necessary for retinal phagocytosis and its daily rhythm. Results: MerTK is cleaved from the apical cell surface in vitro and in vivo, reducing the phagocytic capacity of RPE cells. Conclusion: MerTK cleavage might help control the duration of the daily phagocytic peak. Significance: Our data show that extracellular cleavage of MerTK partly regulates retinal phagocytosis.
  • Stimulation of GLP-1 secretion downstream of the ligand-gated ion channel TRPA1

    Emery, Edward C.; Diakogiannaki, Eleftheria; Gentry, Clive; Psichas, Arianna; Habib, Abdella M.; Bevan, Stuart; Fischer, Michael J.M.; Reimann, Frank; Gribble, Fiona M.; ; et al. (American Diabetes Association Inc., 2014-10-16)
    Stimulus-coupled incretin secretion from enteroendocrine cells plays a fundamental role in glucose homeostasis and could be targeted for the treatment of type 2 diabetes. Here, we investigated the expression and function of transient receptor potential (TRP) ion channels in enteroendocrine L cells producing GLP-1. By microarray and quantitative PCR analysis, we identified trpa1 as an L cell-enriched transcript in the small intestine. Calcium imaging of primary L cells and the model cell line GLUTag revealed responses triggered by the TRPA1 agonists allyl-isothiocyanate (mustard oil), carvacrol, and polyunsaturated fatty acids, which were blocked by TRPA1 antagonists. Electrophysiology in GLUTag cells showed that carvacrol induced a current with characteristics typical of TRPA1 and triggered the firing of action potentials. TRPA1 activation caused an increase in GLP-1 secretion from primary murine intestinal cultures and GLUTag cells, an effect that was abolished in cultures from trpa1-/- mice or by pharmacological TRPA1 inhibition. These findings present TRPA1 as a novel sensory mechanism in enteroendocrine L cells, coupled to the facilitation of GLP-1 release, which may be exploitable as a target for treating diabetes.
  • Fbp17 and cip4 recruit ship2 and lamellipodin to prime the plasma membrane for fast endophilin-mediated endocytosis

    Hak, Laura Chan Wah; Khan, Shaheen; Meglio, Ilaria Di; Law, Ah-Lai; Häsler, Safa Lucken-Ardjomande; Quintaneiro, Leonor M.; Ferreira, Antonio P.A.; Krause, Matthias; McMahon, Harvey T.; Boucrot, Emmanuel; et al. (Nature Publishing Group, 2018-07-30)
    Endocytosis mediates the cellular uptake of micronutrients and the turnover of plasma membrane proteins. Clathrin-mediated endocytosis is the major uptake pathway in resting cells 1 , but several clathrin-independent endocytic routes exist in parallel 2,3 . One such pathway, fast endophilin-mediated endocytosis (FEME), is not constitutive but triggered upon activation of certain receptors, including the β 1 adrenergic receptor 4 . FEME activates promptly following stimulation as endophilin is pre-enriched by the phosphatidylinositol-3,4-bisphosphate-binding protein lamellipodin 4,5 . However, in the absence of stimulation, endophilin foci abort and disassemble after a few seconds. Looking for additional proteins involved in FEME, we found that 20 out of 65 BAR domain-containing proteins tested colocalized with endophilin spots. Among them, FBP17 and CIP4 prime the membrane of resting cells for FEME by recruiting the 5′-lipid phosphatase SHIP2 and lamellipodin to mediate the local production of phosphati-dylinositol-3,4-bisphosphate and endophilin pre-enrichment. Membrane-bound GTP-loaded Cdc42 recruits FBP17 and CIP4, before being locally deactivated by RICH1 and SH3BP1 GTPase-activating proteins. This generates the transient assembly and disassembly of endophilin spots, which lasts 5–10 seconds. This mechanism periodically primes patches of the membrane for prompt responses upon FEME activation.
  • Lipid derivatives activate GPR119 and trigger GLP-1 secretion in primary murine L-cells

    Moss, Catherine E.; Glass, Leslie L.; Diakogiannaki, Eleftheria; Pais, Ramona; Lenaghan, Carol; Smith, David M.; Wedin, Marianne; Bohlooly-Y, Mohammad; Gribble, Fiona M.; Reimann, Frank; et al. (Elsevier Inc., 2015-07-02)
    Aims/hypothesis Glucagon-like peptide-1 (GLP-1) is an incretin hormone derived from proglucagon, which is released from intestinal L-cells and increases insulin secretion in a glucose dependent manner. GPR119 is a lipid derivative receptor present in L-cells, believed to play a role in the detection of dietary fat. This study aimed to characterize the responses of primary murine L-cells to GPR119 agonism and assess the importance of GPR119 for the detection of ingested lipid. Methods GLP-1 secretion was measured from murine primary cell cultures stimulated with a panel of GPR119 ligands. Plasma GLP-1 levels were measured in mice lacking GPR119 in proglucagon-expressing cells and controls after lipid gavage. Intracellular cAMP responses to GPR119 agonists were measured in single primary L-cells using transgenic mice expressing a cAMP FRET sensor driven by the proglucagon promoter. Results L-cell specific knockout of GPR119 dramatically decreased plasma GLP-1 levels after a lipid gavage. GPR119 ligands triggered GLP-1 secretion in a GPR119 dependent manner in primary epithelial cultures from the colon, but were less effective in the upper small intestine. GPR119 agonists elevated cAMP in ∼70% of colonic L-cells and 50% of small intestinal L-cells. Conclusions/interpretation GPR119 ligands strongly enhanced GLP-1 release from colonic cultures, reflecting the high proportion of colonic L-cells that exhibited cAMP responses to GPR119 agonists. Less GPR119-dependence could be demonstrated in the upper small intestine. In vivo, GPR119 in L-cells plays a key role in oral lipid-triggered GLP-1 secretion.

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