Distinct molecular targets of ProEGCG from EGCG and superior inhibition of angiogenesis signaling pathways for treatment of endometriosis

Endometriosis is a common chronic gynecological disease with endometrial cell implantation outside the uterus.Angiogenesis is a major pathophysiology in endometriosis.Our previous studies have demonstrated that the prodrug of epigallocatechin gallate(ProEGCG)exhibits superior anti-endometriotic and anti-angiogenic effects compared to epigallocatechin gallate(EGCG).However,their direct binding targets and underlying mechanisms for the differential effects remain unknown.In this study,we demonstrated that oral ProEGCG can be effective in preventing and treating endometriosis.Additionally,1D and 2D Proteome Integral Solubility Alteration assay-based chemical proteomics identified metadherin(MTDH)and PX domain containing serine/threonine kinase-like(PXK)as novel binding targets of EGCG and ProEGCG,respectively.Computational simulation and BioLayer interferometry were used to confirm their binding affinity.Our results showed that MTDH-EGCG inhibited protein kinase B(Akt)-mediated angiogenesis,while PXK-ProEGCG inhibited epidermal growth factor(EGF)-mediated angiogenesis via the EGF/hypoxia-inducible factor(HIF-1a)/vascular endothelial growth factor(VEGF)pathway.In vitro and in vivo knockdown assays and microvascular network imaging further confirmed the involvement of these signaling pathways.Moreover,our study demonstrated that ProEGCG has superior therapeutic effects than EGCG by targeting distinct signal transduction pathways and may act as a novel antiangiogenic therapy for endometriosis.

Role of 9-Lipoxygenase and α-Dioxygenase Oxylipin Pathways as Modulators of Local and Systemic Defense

Plant 9-1ipoxygenases （9-LOX） and α-dioxygenases （α-DOX） initiate the synthesis of oxylipins after bacterial infection. Here, the role of these enzymes in plants＇ defense was investigated using individual Arabidopsis thaliana Ioxl and doxl mutants and a double Ioxl doxl mutant. Studies with Pseudomonas syringae pv. tomato （Pst） revealed the enhanced susceptibility of Ioxl to the virulent strain Pst DC3000 and the partial impairment of Ioxl and doxl mutants to activate systemic acquired resistance. Notably, both defects were enhanced in the Ioxl doxl plants as compared with individual mutants. We found that pre-treatment with 9-LOX- and α-DOX-generated oxylipins protected plant tissues against bacterial infection. The strongest effect in this respect was exerted by 9-ketooctadecatrienoic acid （9-KOT）, which is produced from linolenic acid by 9-LOX. Quantification of 9-KOT revealed its accumulation after bacterial infection. The levels were reduced in Ioxl and Ioxl doxl plants but strongly increased in the doxl mutant due to metabolic interaction of the two pathways. Transcriptional analyses indicated that 9-KOT pre-treatment modifies hormone homeostasis during bacterial infection. The nature of the changes detected suggested that 9-KOT interferes with the hormonal changes caused by bacterial effectors. This notion was substantiated by the finding that 9-KOT failed to reduce the growth of PstDC3OOOhrpA, a mutant compromised in effector secretion, and of the avirulent strain Pst DC3000 avrRpml. Further support for the action of the 9-LOX- and α-DOX-oxylipin pathways as modulators of hormone homeostasis was the ob- servation that Ioxl doxl seedlings are hypersensitive to the growth-inhibitory effect of ABA and showed enhanced ac- tivation of ABA-inducible marker genes as compared with wild-type plants.

In silico Proteome-wide Amino aCid and Elemental Composition (PACE) Analysis of Expression Proteomics Data Provides A Fingerprint of Dominant Metabolic Processes

Proteome-wide Amino aCid and Elemental composition （PACE） analysis is a novel and informative way of interrogating the proteome. The PACE approach consists of in silico decompo- sition of proteins detected and quantified in a proteomics experiment into 20 amino acids and five elements （C, H, N, O and S）, with protein abundances converted to relative abundances of amino acids and elements. The method is robust and very sensitive; it provides statistically reliable differ- entiation between very similar proteomes. In addition, PACE provides novel insights into prote- ome-wide metabolic processes, occurring, e.g., during cell starvation. For instance, both Escherichia coli and Synechocystis down-regulate sulfur-rich proteins upon sulfur deprivation, but E. coli preferentially down-regulates cysteine-rich proteins while Synechocystis mainly down- regulates methionine-rich proteins. Due to its relative simplicity, flexibility, generality and wide applicability, PACE analysis has the potential of becoming a standard analytical tool in proteomics.

Role of Stable Isotopes in Life——Testing Isotopic Resonance Hypothesis

Stable isotopes of most important biological elements, such as C, H, N and O, affect living organisms. In rapidly growing species, deuterium and to a lesser extent other heavy isotopes reduce the growth rate. At least for deuterium it is known that its depletion also negatively impacts the speed of biological processes. As a rule, living organisms ＂resist＂ changes in their isotopic environment, preferring natural isotopic abundances. This preference could be due to evolutionary optimization; an additional effect could be due to the presence of the ＂isotopic resonance＂. The isotopic resonance phenomenon has been linked to the choice of earliest amino acids, and thus af- fected the evolution of genetic code. To test the isotopic resonance hypothesis, literature data were analyzed against quantitative and qualitative predictions of the hypothesis. Four studies provided five independent datasets, each in very good quantitative agreement with the predictions. Thus, the isotopic resonance hypothesis is no longer simply plausible; it can now be deemed likely. Additional testing is needed, however, before full acceptance of this hypothesis.