The role of Kdr (VEGFR-2/Flk-1) in vascular formation has been well described, but the role of Flt1 (VEGFR-1) is not well studied and is generally considered as a decoy receptor for trapping VEGF.

Curcuminoids are well known for their capabilities to combat risk factors that are associated with ageing and cellular senescence. Recent reports have demonstrated that curcuminoids can extend the lifespan of model organisms. However, the underlying mechanisms by which these polyphenic compounds exert these beneficial effects remain unknown. In this study, t-BHP-induced premature senescence model in human fibroblasts was chosen to explore the protective effects of a curcuminoid, bisdemethoxycurcumin (BDMC), on cellular senescence. The results demonstrated that BDMC attenuated oxidative stress-induced senescence-like features which include the induction of an enlarged cellular appearance, higher frequency of senescence-associated β -galactosidase staining activity, appearance of senescence-associated heterochromatic foci in nuclei, decrease in proliferation capability, and alteration in related molecules such as p16 and retinoblastoma protein. Notably, we found that BDMC treatment activated Sirt1/AMPK signaling pathway. Moreover, downregulating Sirt1 by the pharmacological inhibitor nicotianamine or small interfering RNA blocked BDMC-mediated protection against t-BHP-mediated decrease in proliferation. These results suggested that BDMC prevented t-BHP-induced cellular senescence, and BDMC-induced Sirt1 may be a mechanism mediating its beneficial effects.

Parkinson disease (PD) is a neurodegenerative disease with multifactorial etiopathogenesis. The discovery of drug candidates that act on new targets of PD is required to address the varied pathological aspects and modify the disease process. In this study, a small compound, 2-(5-methyl-1-benzofuran-3-yl)-N-(5-propylsulfanyl-1,3,4-thiadiazol-2-yl) acetamide (MBPTA) was identified as a novel Rho-associated protein kinase inhibitor with significant protective effects against 1-methyl-4-phenylpyridinium ion (MPP(+))-induced damage in SH-SY5Y neuroblastoma cells. Further investigation showed that pretreatment of SH-SY5Y cells with MBPTA significantly suppressed MPP(+)-induced cell death by restoring abnormal changes in nuclear morphology, mitochondrial membrane potential, and numerous apoptotic regulators. MBPTA was able to inhibit MPP(+)-induced reactive oxygen species (ROS)/NO generation, overexpression of inducible NO synthase, and activation of NF-κB, indicating the critical role of MBPTA in regulating ROS/NO-mediated cell death. Furthermore, MBPTA was shown to activate PI3K/Akt survival signaling, and its cytoprotective effect was abolished by PI3K and Akt inhibitors. The structural comparison of a series of MBPTA analogs revealed that the benzofuran moiety probably plays a crucial role in the anti-oxidative stress action. Taken together, these results suggest that MBPTA protects against MPP(+)-induced apoptosis in a neuronal cell line through inhibition of ROS/NO generation and activation of PI3K/Akt signaling.

The mitochondrial respiratory chain, including mitochondrial complex II, has emerged as a potential target for cancer therapy. In the present study, a novel conjugate of danshensu (DSS) and tetramethylpyrazine (TMP), DT-010, was synthesized. Our results showed that DT-010 is more potent than its parental compounds separately or in combination, in inhibiting the proliferation of MCF-7 and MDA-MB-231 cells by inducing cytotoxicity and promoting cell cycle arrest. It also inhibited the growth of 4T1 breast cancer cells in vivo. DT-010 suppressed the fundamental parameters of mitochondrial function in MCF-7 cells, including basal respiration, ATP turnover, maximal respiration. Treatment with DT-010 in MCF-7 and MDA-MB-231 cells resulted in the loss of mitochondrial membrane potential and decreased ATP production. DT-010 also promoted ROS generation, while treatment with ROS scavenger, NAC (N-acetyl-L-cysteine), reversed DT-010-induced cytotoxicity. Further study showed that DT-010 suppressed succinate-induced mitochondrial respiration and impaired mitochondrial complex II enzyme activity indicating that DT-010 may inhibit mitochondrial complex II. Overall, our results suggested that the antitumor activity of DT-010 is associated with inhibition of mitochondrial complex II, which triggers ROS generation and mitochondrial dysfunction in breast cancer cells.

Actinobacteria, a group of gram-positive bacteria, can produce plenty of valuable bioactive secondary metabolites, especially antibiotics. Hence, in order to search for new actinobacteria, actinobacterial isolates were obtained from rhizosphere soil collected from the Futian mangrove ecosystem in Shenzhen, China. According to 16S rRNA sequences, 14 actinobacterial strains of the genus Streptomyces, Rhodococcus, Microbacterium, Micromonospora, Actinoplanes and Mycobacterium were isolated and identified. Among these, strain Mycobacterium sp.13 was described as a potential new species belonging to the genus Mycobacterium within the class of actinobacteria according to the genomic analysis. The genome-based 16S rRNA sequences had 98.48% sequence similarity with Mycobacterium moriokaense DSM 44221T. Meanwhile, the genome sequences of Mycobacterium sp.13 showed an average nucleotide identity (ANI) with the Mycobacterium mageritense DSM 44476, Mycobacterium smegmatis MKD8 and Mycobacterium goodii strain X7B of only 74.79%, 76.12% and 76.42%, respectively. Furthermore, genome-mining results showed that Mycobacterium sp.13 contained 105 gene clusters encoding to the secondary metabolite biosynthesis, where many kinds of terpene, bacteriocin, T1pks, Nrps, saccharide, fatty acid, butyrolactone, ectoine and resorcinol were included. Finally, through LC-MS and HR-MS, analyzing the small molecules from ethyl acetate extract of this strain, asukamycin C and apramycin were for the first time found present to be in Mycobacterium moriokaense strain. Our study provides evidence in support of the potential new Mycobacterium sp.13 isolated from the mangrove environment as a possible novel source of natural products.

Marine invertebrates, such as sponges, tunicates and cnidarians (zoantharians and scleractinian corals), form functional assemblages, known as holobionts, with numerous microbes. This type of species-specific symbiotic association can be a repository of myriad valuable low molecular weight organic compounds, bioactive peptides and enzymes. The zoantharian Protopalythoa variabilis (Cnidaria: Anthozoa) is one such example of a marine holobiont that inhabits the coastal reefs of the tropical Atlantic coast and is an interesting source of secondary metabolites and biologically active polypeptides. In the present study, we analyzed the entire holo-transcriptome of P. variabilis, looking for enzyme precursors expressed in the zoantharian-microbiota assemblage that are potentially useful as industrial biocatalysts and biopharmaceuticals. In addition to hundreds of predicted enzymes that fit into the classes of hydrolases, oxidoreductases and transferases that were found, novel enzyme precursors with multiple activities in single structures and enzymes with incomplete Enzyme Commission numbers were revealed. Our results indicated the predictive expression of thirteen multifunctional enzymes and 694 enzyme sequences with partially characterized activities, distributed in 23 sub-subclasses. These predicted enzyme structures and activities can prospectively be harnessed for applications in diverse areas of industrial and pharmaceutical biotechnology.

G-protein coupled receptor 55 (GPR55) is an orphan G-protein coupled receptor, which is activated by endocannabinoids and lipid transmitters. Recently, GPR55 was shown to play a role in glucose and energy homeostasis, and insulin secretion is essential to maintain glucose homeostasis in the body. In Type 2 Diabetes Mellitus (T2DM), chronic insulin resistance and a progressive decline in β-cell function result in β-cell dysfunction, this leads to defect in insulin secretion, which is the key process in the development and progression of T2DM. GPR55 agonists were shown to increase insulin secretion, however the underlying mechanisms were not fully understood. Therefore the aim of the present study was to examine the effects of potent GPR55 agonists, O-1602 and abnormal cannabidiol (Abn-CBD), on glucose-induced insulin secretion in a mouse pancreatic β-cell line, MIN6, and the underlying mechanisms with a focus on intracellular calcium (Ca2+). Our results demonstrated that O-1602 and Abn-CBD increased glucose-induced insulin secretion in MIN6 cells, which was abolished by a PLC inhibitor, U73122. Glucose-induced Ca2+ transients were enhanced by O-1602 and Abn-CBD, and this was significantly reduced by U73122 and inositol trisphosphate (IP3) receptor inhibitors, 2-aminoethoxydiphenyl borate (2-APB) and xestospongin C, as well as by Y-27632, a Rho-associated protein kinase (ROCK) inhibitor. Interestingly, O-1602 and Abn-CBD could directly induce intracellular Ca2+ transients through IP3-mediated Ca2+ release. In conclusion, GPR55 agonists increased insulin secretion through calcium mobilisation from IP3-sensitive ER stores in β-cells.

Actinobacteria are well recognized for their production of structurally diverse bioactive secondary metabolites, but the rare actinobacterial genera have been underexploited for such potential. To search for new sources of active compounds, an experiment combining genomic analysis and tandem mass spectrometry (MS/MS) screening was designed to isolate and characterize actinobacterial strains from a mangrove environment in Macau. Fourteen actinobacterial strains were isolated from the collected samples. Partial 16S sequences indicated that they were from six genera, including Brevibacterium, Curtobacterium, Kineococcus, Micromonospora, Mycobacterium, and Streptomyces. The isolate sp.01 showing 99.28% sequence similarity with a reference rare actinobacterial species Micromonospora aurantiaca ATCC 27029T was selected for whole genome sequencing. Organization of its gene clusters for secondary metabolite biosynthesis revealed 21 clusters encoded to antibiotic production, which is higher than other Micromonospora species. Of the genome-predicted antibiotics, kanamycin was found through guided MS/MS analysis producible by the M. aurantiaca strain for the first time. The present study highlighted that genomic analysis combined with MS/MS screening is a promising method to discover potential of antibiotic production from rare actinobacteria.

Mangroves are a group of plant species that occupy the coastal intertidal zone and are major components of this ecologically important ecosystem. Mangroves belong to about twenty diverse families. Here, we sequenced and assembled chloroplast genomes of 14 mangrove species from eight families spanning five rosid orders and one asterid order: Fabales (Pongamia pinnata), Lamiales (Avicennia marina), Malpighiales (Excoecaria agallocha, Bruguiera sexangula, Kandelia obovata, Rhizophora stylosa, and Ceriops tagal), Malvales (Hibiscus tiliaceus, Heritiera littoralis, and Thespesia populnea), Myrtales (Laguncularia racemosa, Sonneratia ovata, and Pemphis acidula), and Sapindales (Xylocarpus moluccensis). These chloroplast genomes range from 149 kb to 168 kb in length. A conserved structure of two inverted repeats (IRa and IRb, ~25.8 kb), one large single-copy region (LSC, ~89.0 kb), and one short single-copy region (SSC, ~18.9 kb) as well as ~130 genes (85 protein-coding, 37 tRNAs, and 8 rRNAs) was observed. We found the lowest divergence in the IR regions among the four regions. We also identified simple sequence repeats (SSRs), which were found to be variable in numbers. Most chloroplast genes are highly conserved, with only four genes under positive selection or relaxed pressure. Combined with publicly available chloroplast genomes, we carried out phylogenetic analysis and confirmed the previously reported phylogeny within rosids, including the positioning of obscure families in Malpighiales. Our study reports 14 mangrove chloroplast genomes and illustrates their genome features and evolution.

Understanding the behaviors of nanomedicines in vivo is one of the most important prerequisites for the design and optimization of nanomedicines. However, the in vivo tracking of nanomedicines in rodents is severely limited by the restricted imaging possibilities within these animals. To meet these needs, the FRET (fluorescence or Förster resonance energy transfer) imaging combined with visual zebrafish larvae model (7 dpf) was used to study the behaviors of polymeric micelles in vivo at high spatiotemporal resolution. Firstly, the FRET ordinary Pluronic micelles (OPMs) and disulfide bond crosslinked Pluronic micelles (CPMs) were synthesized to quantify their integrity in vitro and in vivo by FRET ratio. The behaviors and integrity of OPMs and CPMs in vivo were visually investigated in zebrafish larvae across the entire living organism and at cellular molecular level after intravenous microinjection. Results showed that OPMs were rapidly disassociated in circulation, then largely sequestrated by the endothelial cells (ECs) of caudal vein (CV) and liver in zebrafish larvae, which resulted in quick elimination from blood circulation. While the CPMs were more stable and escaped the sequestration by ECs of CV and liver, which prolonged their circulation in blood. Moreover, we pioneered to use the zebrafish model to reveal that polymeric micelles were eliminated through hepatobiliary pathway after disassociation. While the intact micelles were relatively difficult to eliminate. We further verified that the scavenger receptors of ECs but not the macrophages mainly mediated the elimination of polymeric micelles in CV and liver of zebrafish larvae. These finding on behaviors and elimination mechanisms of polymeric micelles in zebrafish model could contribute to the rational design and optimization of nanomedicines, further guide their studies in rodents.

Parkinson's disease (PD), the second most common neurodegenerative disorder, is neuropathologically characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta (SNc) and the presence of Lewy bodies in surviving neurons. α-synuclein (α-syn) is the major component of Lewy bodies and its deposition in neurons is critical pathological event in the pathogenesis of PD. Herein, we reported that Oxyphylla A, a novel lead compound from the fruit of Alpinia oxyphylla, significantly promoted α-syn degradation in a cellular PD model. When exploring the molecular pathways, we found that Oxyphylla A promoted α-syn degradation in a ubiquitin proteasome system (UPS)-dependent and autophagy-independent manner. We further confirmed that Oxyphylla A enhanced UPS activity by upregulating 20S subunit PSMB8 expression. A mechanism study revealed that Oxyphylla A activated the PKA/Akt/mTOR pathway to trigger PSMB8 expression and enhance UPS activity. Finally, we illustrated that Oxyphylla A alleviated the accumulation of both Triton-soluble and Triton-insoluble forms of α-syn and protected against α-syn-induced neurotoxicity in A53T α-syn transgenic mice. These findings suggest that the activation of UPS, via small molecular UPS enhancers including Oxyphylla A, may be a therapeutic strategy for intervention against PD and related diseases.

Mangroves are intertidal extreme environments with rich microbial communities. Actinobacteria are well known for producing antibiotics. The search for biosynthetic potential of Actinobacteria from mangrove environments could provide more possibilities for useful secondary metabolites. In this study, whole genome sequencing and MS/MS analysis were used to explore the secondary metabolite production potential of one actinobacterial strain of Streptomyces olivaceus sp., isolated from a mangrove in Macau, China. The results showed that a total of 105 gene clusters were found in the genome of S. olivaceus sp., and 53 known secondary metabolites, including bioactive compounds, peptides, and other products, were predicted by genome mining. There were 28 secondary metabolites classified as antibiotics, which were not previously known from S. olivaceus. ISP medium 2 was then used to ferment the S. olivaceus sp. to determine which predicted secondary metabolite could be truly produced. The chemical analysis revealed that ectoine, melanin, and the antibiotic of validamycin A could be observed in the fermentation broth. This was the first observation that these three compounds can be produced by a strain of S. olivaceus. Therefore, it can be concluded that Actinobacteria isolated from the mangrove environment have unknown potential to produce bioactive secondary metabolites.

In hypoxia and hyperglycemia, SET7/9 plays an important role in controlling HIF-1α methylation and regulating the transcription of HIF-1α target genes, which are responsible for angiogenesis and wound healing. Here, we report the Ir(III) complex Set7_1a bearing acetonitrile (ACN) ligands as a SET7/9 methyltransferase inhibitor and HIF-1α stabilizer. Interestingly, Set7_1a could engage SET7/9 and strongly inhibit SET7/9 activity, especially after preincubation with homocysteine (Hcy), which is elevated in diabetes. We hypothesize that Set7_1a exchanges ACN subunits for Hcy to disrupt the interaction between SET7/9 and SAM/SAH, which are structurally related to Hcy. Inhibition of SET7/9 methyltransferase activity by Set7_1a led to reduced HIF-1α methylation at the lysine 32 residue, causing increased HIF-1α level and recruitment of HIF-1α target genes that promote angiogenesis, such as VEGF, GLUT1, and EPO, in hypoxia and hyperglycemia. Significantly, Set7_1a improved wound healing in a type 2 diabetic mouse model by activating HIF-1α signaling and downstream proangiogenic factors. To our knowledge, this is the first Hcy-targeting iridium compound shown to be a SET7/9 antagonist that can accelerate diabetic wound healing. More importantly, this study opens a therapeutic avenue for the treatment of diabetic wounds by the inhibition of SET7/9 lysine methyltransferase activity.

Natural products present in low quantity in herb medicines constitute an important source of chemical diversity. However, the isolation of sufficient amounts of these low abundant constituents for structural modification has been a challenge for several decades and subsequently halts research on the utilization of this important source of chemical entities for drug discovery and development. And, pro-angiogenic therapies are being explored as options to treat cardio-cerebral vascular diseases and wound healing recently. The present study investigates the pro-angiogenic potential of tanshinone derivatives produced by one-pot synthesis using zebrafish model.

Adult giant pandas (Ailuropoda melanoleuca) express transitional characteristics in that they consume bamboos, despite their carnivore-like digestive tracts. Their genome contains no cellulolytic enzymes; therefore, understanding the development of the giant panda gut microbiome, especially in early life, is important for decoding the rules underlying gut microbial formation, inheritance and dietary transitions. With deep metagenomic sequencing, we investigated the gut microbiomes of two newborn giant panda brothers and their parents living in Macao, China, from 2016 to 2017. Both giant panda cubs exhibited progressive increases in gut microbial richness during growth, particularly from the 6th month after birth. Enterobacteriaceae dominated the gut microbial compositions in both adult giant pandas and cubs. A total of 583 co-abundance genes (CAGs) and about 79 metagenomic species (MGS) from bacteria or viruses displayed significant changes with age. Seven genera (Shewanella, Oblitimonas, Helicobacter, Haemophilus, Aeromonas, Listeria, and Fusobacterium) showed great importance with respect to gut microbial structural determination in the nursing stage of giant panda cubs. Furthermore, 10 orthologous gene functions and 44 pathways showed significant changes with age. Of the significant pathways, 16 from Escherichia, Klebsiella, Propionibacterium, Lactobacillus, and Lactococcus displayed marked differences between parents and their cubs at birth, while 29 pathways from Escherichia, Campylobacter and Lactobacillus exhibited significant increase in cubs from 6 to 9 months of age. In addition, oxidoreductases, transferases, and hydrolases dominated the significantly changed gut microbial enzymes during the growth of giant panda cubs, while few of them were involved in cellulose degradation. The findings indicated diet-stimulated gut microbiome transitions and the important role of Enterobacteriaceae in the guts of giant panda in early life.

Parkinson's disease (PD) is a chronic neurodegenerative disorder having close relationship with oxidative stress induced by reactive oxygen species (ROS). Cortex Fraxini (QP) is a kind of traditional Chinese medicinal herb with antioxidant properties. It may be a potential candidate for preventing the development of chronic neurodegenerative diseases. Thus, the key objective of the current study was to investigate the neuroprotective effect of QP water extract on 6-hydroxydopamine (6-OHDA) induced apoptosis in rat pheochromocytoma (PC12) cells. It was found that QP water extract possesses strong antioxidant property with SC50 = 0.15 mg/mL. Total phenolic content of QP water extract was found to be 200.78 ± 2.65 mg GAE/g. QP water extract's free radical scavenging capacity was demonstrated by reversing the increased level of intracellular ROS induced by 6-OHDA, using 2',7'-dichlorodihydrofluorescein diacetate. Moreover, QP water extract (0.5 mg/mL) could remarkably increase the viability of PC12 cells treated with 6-OHDA. The protective effect of QP water extract was found to be via inhibiting MEK/ERK pathway and reversing PI3-K/Akt/GSK3β pathway. The current results suggest that QP might be a potential candidate for preventing the development of neurodegenerative diseases, such as PD.

Panax notoginseng (Burk.) F.H. Chen is one of the most highly valued medicinal plants in the world. The major bioactive molecules are triterpene saponins, which are also known as ginsenosides. However, its large genome size has hindered the assembly of a draft genome by whole genome sequencing. Hence, genomic and transcriptomic details about P. notoginseng, especially its biosynthetic pathways and gene expression in different parts of the plant, have remained largely unknown until now.

Hemorrhagic stroke occurs when a weakened vessel ruptures and bleeds into the surrounding brain, leading to high rates of death and disability worldwide. A series of complex pathophysiological cascades contribute to the risk of hemorrhagic stroke, and no therapies have proven effective to prevent hemorrhagic stroke. Stabilization of vascular integrity has been considered as a potential therapeutic target for hemorrhagic stroke. ROCKs, which belong to the serine/threonine protein kinase family and participate in the organization of actin cytoskeleton, have become attractive targets for the treatment of strokes. In this study, in vitro enzyme-based assays revealed that a new compound (FPND) with a novel scaffold identified by docking-based virtual screening could inhibit ROCK1 specifically at low micromolar concentration. Molecular modeling showed that FPND preferentially interacted with ROCK1, and the difference between the binding affinity of FPND toward ROCK1 and ROCK2 primarily resulted from non-polar contributions. Furthermore, FPND significantly prevented statin-induced cerebral hemorrhage in a zebrafish model. In addition, in vitro studies using the xCELLigence RTCA system, immunofluorescence and western blotting revealed that FPND prevented statin-induced cerebral hemorrhage by enhancing endothelial cell-cell junctions through inhibiting the ROCK-mediated VE-cadherin signaling pathway. As indicated by the extremely low toxicity of FPND against mice, it is safe and can potentially prevent vascular integrity loss-related diseases, such as hemorrhagic stroke.

Aberrant activation of the innate immune system, including NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome-dependent interleukin-1β (IL-1β) secretion, has been implicated in the pathogenesis of type 2 diabetes mellitus (T2DM) and its complication. Our previous study demonstrated that hyperglycemia, a hallmark characteristic of T2DM, induced NLRP3 inflammasome-dependent caspase-1 activation and IL-1β maturation in human monocytic cells. In this study, we examined the underlying mechanisms of secreting IL-1β during hyperglycemia, with a focus on the alteration of Ca2+ homeostasis and lysosomal exocytosis. We found that high glucose (HG; 30 mM glucose for 48 h) altered Ca2+ homeostasis by reducing lysosomal Ca2+ concentration that appeared to be resulted from Ca2+ moving out of lysosomes into cytosol in human monocytic cell lines, U937 and THP-1 cells. Moreover, HG-induced lysosomal Ca2+-dependent mature IL-1β release was strongly correlated with the activation and upregulation of two lysosomal marker proteins, cathepsin D and lysosomal-associated membrane protein-1 (LAMP-1). This involved calcineurin/transcription factor EB (TFEB) pathway and its target genes, cathepsin B, cathepsin D, and LAMP-1, to mediate lysosomal exocytosis. Therefore in this study, we revealed a novel mechanism of HG-induced lysosomal exocytosis which was regulated by lysosomal Ca2+ signals through calcineurin/TFEB pathway, thus contributing to IL-1β secretion in human monocytic cells.

Mei (Prunus mume) is an ornamental woody plant that has been domesticated in East Asia for thousands of years. High diversity in floral traits, along with its recent genome sequence, makes mei an ideal model system for studying the evolution of woody plants. Here, we investigate the genetic architecture of floral traits in mei and its domestication history by sampling and resequencing a total of 351 samples including 348 mei accessions and three other Prunus species at an average sequencing depth of 19.3×. Highly-admixed population structure and introgression from Prunus species are identified in mei accessions. Through a genome-wide association study (GWAS), we identify significant quantitative traits locus (QTLs) and genomic regions where several genes, such as MYB108, are positively associated with petal color, stigma color, calyx color, and bud color. Results from this study shed light on the genetic basis of domestication in flowering plants, particularly woody plants.