β-Diglycosidases from microorganisms as industrial biocatalysts: biochemical characteristics and potential applications

Flavonoid glycoside degradation can proceed through two alternative enzymatic pathways: one that is mediated by monoglycosidases, and the other catalyzed by a diglycosidase. β-Diglycosidase performs the flavonoid deglycosylation in a single reaction. The characterized β-diglycosidase activities recognize the following disaccharidic sugar moieties: β-primeverose, acuminose, vicianose, and β-rutinose. The present paper reviews the biochemical characteristics and potential industrial applications of microbial β-diglycosidases that break down plant diglycoconjugated flavonoids.

     

Decoction of heat-clearing,detoxifying and blood stasis removing relieves acute soft tissue injury via modulating miR-26b-5p/COX2 axis to inhibit inflammation

Traditional Chinese medicine (TCM), such as Huanglian-Jie-Du-Tang, a heat-clearing and detoxifying decoction is beneficial for alleviation of inflammation-related diseases. The objective of the present study is to uncover the effect and mechanism of heat-clearing, detoxifying and blood stasis removing decoction (HDBD) on the treatment of acute soft tissue injury (STI) which is characterized with excessive inflammatory cascade at the onset. Male Sprague–Dawley (SD) rats with hammer beating served as the in vivo models of acute STI. Hematoxylin–Eosin (HE) staining was used for histopathology assessment. The levels of inflammatory factors, including prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), interleukin (IL)-1t and IL-6 were measured by enzyme-linked immunosorbent assay (ELISA). Human dermal microvascular endothelium cell line HMEC-1 and rat vascular endothelium cell line RAOEC were used to explore the mechanism in vitro. Luciferase gene reporter assay was applied to determine the relationship between miR-26b-5p and Cyclo-oxygenase 2 (COX2). The results showed that HDBD intervention significantly reduced the temperature difference between the healthy side and affected side of rats with hammer beating, together with the decreased levels of COX2, PGE2, TNF-α, IL-6 and IL-1β, and the increased level of miR-26b-5p. In mechanism, miR-26b-5p targeted COX2 and decreased its expression, leading to significant decreases in the levels of PGE2, TNF-α and IL-6 in RAOEC and HMEC-1 cells. In addition, miR-26b-5p inhibition impaired the effects of HDBD on the suppression of PGE2, TNF-α, IL-6 and IL-1β in vitro. In conclusion, the present study revealed that HDBD relieved acute STI via modulating miR-26b-5p/COX2 axis to inhibit inflammation.     

Genetic depletion of glutathione peroxidase-1 potentiates nephrotoxicity induced by multiple doses of cocaine via activation of angiotensin II AT1 receptor

We investigated the possible roles of angiotensin II type 1 receptor (AT1R) and oxidative stress responsive nuclear factor κB (NFκB) in renal damage caused by multiple doses of cocaine in glutathione peroxidase (GPx)-1 gene-depleted mice. Treatment with cocaine resulted in significant increases in malondialdehyde, protein carbonyl, and pro-apoptotic Bax expression and decreases in the ratio of glutathione (GSH) and its oxidized form (GSSG), GSH-dependent enzymes, and anti-apoptotic factors in the kidney. These alterations were more pronounced in GPx-1 knockout (?/?) mice than in wild type (WT) mice. Notably, the AT1R antagonist losartan protected against the renal toxicity induced by cocaine, whereas the NFκB inhibitor pyrrolidine dithiocarbamate was not protective. The toxicity was more pronounced in GPx-1 (?/?) mice than in WT mice. The protective effect afforded by losartan against cocaine toxicity appeared to be more sensitive in GPx-1 (?/?) mice than that in WT mice. These losartan-mediated protective effects were inhibited by the phosphatidyl-inositol-3-kinase (PI3K) inhibitor LY294002, indicating that losartan provides significant protection from cocaine-induced renal toxicity through PI3K/Akt signaling. Our results suggest that genetic inhibition of GPx-1 potentiates cocaine-induced renal damage via activation of AT1R by inhibition of PI3K-Akt signaling, and that AT1R can be a therapeutic target against renal toxicity induced by cocaine.     

Association of Eriophyes dimocarpi (Acari: Eriophyidae) with longan witches’ broom disease in Vietnam

Longan witches’ broom (LgWB) syndrome was observed in all longan-growing provinces of Vietnam. Key symptoms include: small, stunted shoots with curved, rolled up margins, deformed leaves with blisters and hairy patches on the underside; abnormal development of flower structures, flower abortion, failure to produce fruits or developing small fruits. During 2012–2015, field surveys and study of the relationship between LgWB symptoms and Eriophyes dimocarpi mites presence were carried out. Moreover, molecular analysis, electron microscopy observations, E. dimocarpi inoculations, pruning of affected spikelets and miticide experiments were performed. An average of 36.58% of longan seedlings inoculated with E. dimocarpi mites showed typical symptoms of LgWB at about 27.5 days after inoculation. The use of several pesticides in different combinations showed high efficacy on E. dimocarpi mites elimination and of symptomatology incidence reduction. These results suggest a significant association of E. dimocarpi with LgWB syndrome in Vietnam.     

Spontaneous Ejaculation in a Wild Indo-Pacific Bottlenose Dolphin (Tursiops aduncus)

Spontaneous ejaculation, which is defined as the release of seminal fluids without apparent sexual stimulation, has been documented in boreoeutherian mammals. Here we report spontaneous ejaculation in a wild Indo-Pacific bottlenose dolphin (Tursiops aduncus), and present a video of this rare behavior. This is the first report of spontaneous ejaculation by an aquatic mammal, and the first video of this behavior in animals to be published in a scientific journal.     

Multiple mechanisms for exogenous heparin modulation of vascular endothelial growth factor activity

Heparin and heparin‐like molecules are known to modulate the cellular responses to vascular endothelial growth factor‐A (VEGF‐A). In this study, we investigated the likely mechanisms for heparin's influence on the biological activity of VEGF‐A. Previous studies have shown that exogenous heparin's effects on the biological activity of VEGF‐A are many and varied, in part due to the endogenous cell‐surface heparan sulfates. To circumvent this problem, we used mutant endothelial cells lacking cell‐surface heparan sulfates. We showed that VEGF‐induced cellular responses are dependent in part on the presence of the heparan sulfates, and that exogenous heparin significantly augments VEGF's cellular effects especially when endogenous heparan sulfates are absent. Exogenous heparin was also found to play a cross‐bridging role between VEGF‐A₁₆₅ and putative heparin‐binding sites within its cognate receptor, VEGFR2 when they were examined in isolation. The cross‐bridging appears to be more dependent on molecular weight than on a specific heparin structure. This was confirmed by surface plasmon resonance binding studies using sugar chips immobilized with defined oligosaccharide structures, which showed that VEGF‐A₁₆₅ binds to a relatively broad range of sulfated glycosaminoglycan structures. Finally, studies of the far‐UV circular dichroism spectra of VEGF‐A₁₆₅ showed that heparin can also modulate the conformation and secondary structure of the protein. J. Cell. Biochem. 111: 461–468, 2010. © 2010 Wiley‐Liss, Inc.     

International stem cell registries

Rapid advances in stem cell research have led to the derivation of hundreds of human embryonic stem (hES) cell lines in centers throughout the world, as well as the development of new technologies for producing pluripotent stem cells. These cell lines have unique characteristics and were derived using a variety of ethical guidelines. Stem cell registries have been developed in order to collect, organize, and disseminate cell line-specific information. In this review, we describe the current state of the field by providing an overview of the unique qualities and mandates of the three major stem cell registries: the European hES Cell Registry, the Registry of hES Cell Line Provenance developed by the International Society for Stem Cell Research, and the International Stem Cell Registry of hES and induced pluripotent stem cell lines established at the University of Massachusetts Medical School. While each registry has its own unique mandate and features, there is some overlap in the goals and information provided. This review discusses the challenges and prospects for an integrated approach in which all three registries effectively collaborate to minimize duplication and facilitate information exchange within the stem cell community.     

Chalcone glycosides from aerial parts of Brassica rapa L. ‘hidabeni’, turnip

A phytochemical investigation of the aerial parts of Brassica rapa L. ‘hidabeni’, turnip resulted in the isolation of three new chalcone glycosides, 4′-O-β-d-glucopyranosyl-4-hydroxy-3′-methoxychalcone (1), 4′-O-β-d-glucopyranosyl-3′,4-dimethoxychalcone (2) and 4,4′-di-O-β-d-glucopyranosyl-3′-methoxychalcone (3) along with three known glycosides. The structures of the three newly isolated chalcone glycosides were elucidated on the basis of 1D and 2D NMR and mass spectroscopy.