Wheat germ lipase catalyzed kinetic resolution of secondary alcohols in non-aqueous media

The lipase from wheat germ was used for the kinetic resolution of secondary alcohols. It has the opposite enantioselectivity against the Kazlauskas rule and acts as an anti-Kazlauskas catalyst. The effect of initial water activity, organic solvent, acyl donor and temperature were investigated. Wheat germ lipase had a high activity and enantioselectivity only in n-hexane with a high initial water activity (α_w = 0.97), especially with 1-phenylethanol (C 32%, E > 200). Its performance changed little with the chain length of acyl donor and temperature. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Diabetes Promotes DMH-Induced Colorectal Cancer by Increasing the Activity of Glycolytic Enzymes in Rats

The objective of the present study was to investigate the association between diabetes mellitus and colorectal carcinogenesis as well as the possible mechanism involved in this interaction. Diabetes rat models were induced with a low dose of STZ followed by a low dose of DMH to induce colorectal cancer. The formation of ACF in the colon and the incidence, number and size of tumors were measured. The activity of glycolytic enzymes in colonic tissues was also measured. The results demonstrated that both the total number of ACF and the number of foci that contain a different number of crypts were increased in diabetic rats. At the end of the experimental treatment, the incidence, number and size of tumors were also increased in diabetic rats. Overall, these data indicated that diabetes increased the risk of colorectal cancer. The activity of HK and PK in colonic tissues was increased in diabetic rats, whereas the activity of PDH was decreased. In addition, the activities of these enzymes in intratumor were higher than that of in peritumor. These data indicated that the high rate of glycolysis may play a role in colorectal carcinogenesis in diabetic rats.     

Differentiation of Rabbit Bone Mesenchymal Stem Cells into Endothelial Cells In Vitro and Promotion of Defective Bone Regeneration In Vivo

Tissue engineering strategies often fail to regenerate bones because of inadequate vascularization, especially in the reconstruction of large segmental bone defects. Large volumes of vascular endothelial cells (ECs) that functionally interact with osteoblasts during osteogenesis are difficult to obtain. In this study, we simulated bone healing by co-culturing differentiated ECs and mesenchymal stem cells (MSCs) either on a culture plate or on a polylactide glycolic acid (PLGA) scaffold in vitro. We also evaluated the effect of osteogenesis in repairing rabbit mandible defects in vivo. In this study, MSCs were separated from rabbit as the seed cells. After passage, the MSCs were cultured in an EC-conditioned medium to differentiate into ECs. Immunohistochemical staining analysis with CD34 showed that the induced cells had the characteristics of ECs and MSC. The induced ECs were co-cultured in vitro, and the induction of MSCs to osteoblast served as the control. Alkaline phosphatase (ALP) and alizarin red (AZR) staining experiments were performed, and the Coomassie brilliant blue total protein and ALP activity were measured. The MSCs proliferated and differentiated into osteoblast-like cells through direct contact between the derived ECs and MSCs. The co-cultured cells were seeded on PLGA scaffold to repair 1 cm mandible defects in the rabbit. The effectiveness of the repairs was assessed through soft X-ray and histological analyses. The main findings indicated that MSCs survived well on the scaffold and that the scaffold is biocompatible and noncytotoxic. The results demonstrated that the co-cultured MSC-derived ECs improved MSC osteogenesis and promoted new bone formation. This study may serve as a basis for the use of in vitro co-culturing techniques as an improvisation to bone tissue engineering for the repair of large bone defects.     

Evolutionary relationships of Pemphigus and allied genera (Hemiptera: Aphididae: Eriosomatinae) and their primary endosymbiont,Buchnera aphidicola

Aphids harbor primary endosymbionts, Buchnera aphidicola, in specialized cells within their body cavities. Aphids and Buchnera have strict mutualistic relationships in nutrition exchange. This ancient association has received much attention from researchers who are interested in endosymbiotic evolution. Previous studies have found parallel phylogenetic relationships between non‐galling aphids and Buchnera at lower taxonomic levels (genus, species). To understand whether relatively isolated habitats such as galls have effect on the parallel relationships between aphids and Buchnera, the present paper investigated the phylogenetic relationships of gall aphids from Pemphigus and allied genera, which induce pseudo‐galls or galls on Populus spp. (poplar) and Buchnera. The molecular phylogenies inferred from three aphid genes (COI, COII and EF‐1α) and two Buchnera genes (gnd, 16S rRNA gene) indicated significant congruence between aphids and Buchnera at generic as well as interspecific levels. Interestingly, both aphid and Buchnera phylogenies supported three main clades corresponding to the galling locations of aphids, namely leaf, the joint of leaf blade and petiole, and branch of the host plant. The results suggest phylogenetic conservatism of gall characters, which indicates gall characters are more strongly affected by aphid phylogeny, rather than host plants.     

Protective Effects of 28-O-Caffeoyl Betulin (B-CA) on the Cerebral Cortex of Ischemic Rats Revealed by a NMR-Based Metabolomics Analysis

28-O-caffeoyl betulin (B-CA) has been demonstrated to reduce the cerebral infarct volume caused by transient middle cerebral artery occlusion (MCAO) injury. B-CA is a novel derivative of naturally occurring caffeoyl triterpene with little information associated with its pharmacological target(s). To date no data is available regarding the effect of B-CA on brain metabolism. In the present study, a ¹H-NMR-based metabolomics approach was applied to investigate the therapeutic effects of B-CA on brain metabolism following MCAO in rats. Global metabolic profiles of the cortex in acute period (9 h after focal ischemia onset) after MCAO were compared between the groups (sham; MCAO?+?vehicle; MCAO?+?B-CA). MCAO induced several changes in the ipsilateral cortex of ischemic rats, which consequently led to the neuronal damage featured with the downregulation of NAA, including energy metabolism dysfunctions, oxidative stress, and neurotransmitter metabolism. Treatment with B-CA showed statistically significant rescue effects on the ischemic cortex of MCAO rats. Specifically, treatment with B-CA ameliorated the energy metabolism dysfunctions (back-regulating the levels of succinate, lactate, BCAAs, and carnitine), oxidative stress (upregulating the level of glutathione), and neurotransmitter metabolism disturbances (back-regulating the levels of γ-aminobutyric acid and acetylcholine) associated with the progression of ischemic stroke. With the administration of B-CA, the levels of three phospholipid related metabolites (O-phosphocholine, O-phosphoethanolamine, sn-glycero-3-phosphocholine) and NAA improved significantly. Overall, our findings suggest that treatment with B-CA may provide neuroprotection by augmenting the metabolic changes observed in the cortex following MCAO in rats.

     

LINC00958 facilitates cervical cancer cell proliferation and metastasis by sponging miR-625-5p to upregulate LRRC8E expression

Accepted as a malignant tumor worldwide, cervical cancer (CC) has attracted much attention for its high incidence and mortality rates. Previous studies have elucidated the critical regulatory function that long noncoding RNAs (lncRNAs) exert on the tumorigenesis and progression of diverse tumors. Although multiple investigations have depicted that LINC00958 has a great impact on the complex biological process of many cancers, knowledge concerning the regulatory role of LINC00958 in CC remains limited and needs to be further explored. In our study, LINC00958 expression was evidently overexpressed in CC tissues and cells. Besides this, LINC00958 negatively regulated miR-625-5p expression and was verified to bind with miR-625-5p in CC. Subsequently, it was testified by a series of experiments that LINC00958 promotes CC cell proliferation and metastasis by sponging miR-625-5p. Furthermore, the leucine-rich repeat containing the eight family member E (LRRC8E) could bind with miR-625-5p, and its expression was negatively modulated by miR-625-5p, whereas positively regulated by LINC00958 in CC. Final rescue assays verified the effects of LINC0095/LRRC8E interaction and miR-625-5p/LRRC8E interaction on CC cell proliferation and metastasis. Collectively, LINC00958 facilitates CC cell proliferation and metastasis via the miR-625-5p/LRRC8E axis.     

Sirt3 Protects Against Ischemic Stroke Injury by Regulating HIF-1α/VEGF Signaling and Blood–Brain Barrier Integrity

Sirtuin 3 (Sirt3) is a member of the Sirtuin family proteins and known to regulate multiple physiological processes such as metabolism and aging. As stroke is an aging-related disease, in this work, we attempt to examine the role and potential mechanism of Sirt3 in regulating ischemic stroke by using a permanent middle cerebral artery occlusion (pMCAO) model in wild type (WT) and Sirt3 knockout (KO) mice, coupled with oxygen glucose deprivation (OGD) experiments in cultured primary astrocytes. Sirt3 deficiency aggravated neuronal cell apoptosis and neurological deficits after brain ischemia. In addition, Sirt3 KO mice showed more severe blood–brain barrier (BBB) disruption and inflammatory responses compared with WT group in the acute phase. Furthermore, specific overexpression of Sirt3 in astrocytes by injecting glial fibrillary acidic protein (GFAP)::Sirt3 virus in ischemic region showed protective effect against stroke-induced damage. Mechanistically, Sirt3 could regulate vascular endothelial growth factor (VEGF) expression by inhibiting hypoxia inducible factor-1α (HIF-1α) signaling after ischemia (OGD). Our results have shown that Sirt3 plays a protective role in ischemic stroke via regulating HIF-1α/VEGF signaling in astrocytes, and reversal of the Sirt3 expression at the acute phase could be a worthy direction for stroke therapy.

     

Assessing temporal dynamics of predation and effectiveness of caterpillar visual defense using sawfly larval color and resting posture as a model

Caterpillars (Lepidoptera and Symphyta larvae) employ diverse visual defensive tactics, and effectiveness of such tactics may be highly dynamic across time due to seasonal changes in the predator assemblages and their preferences. However, this has rarely been studied especially in tropical regions. Here we assessed temporal changes in the defensive value of caterpillar color and shape, using six types of plasticine dummy caterpillars: three colors (green, black, and white) × two shapes (curled and straight). These dummy caterpillars were deployed five times over different seasons in tropical forests of Xishuangbanna (China) and, as a comparison, twice in a temperate forest of Hirosaki (Japan). The colors and shapes of dummy caterpillars simulate visual traits of black sawfly larvae which take the curled resting posture in tropical rainforests of Xishuangbanna, apparently masquerading excrements commonly found on plants, while in Hirosaki there is no black-curled sawfly larvae and few excrements on plants. We found no significant effects of caterpillar colors or shapes on predation in Hirosaki. In contrast, black and curled caterpillars received significantly lower predation by birds in Xishuangbanna constantly across time. However, we were unable to provide evidence that the black-curled sawfly larvae are masquerading as excrements. Shapes of the dummy caterpillars also affected the predation by ants and parasitoid wasps at certain times. This is the first report on ecological function of the curled posture of sawfly larvae, and we demonstrated the importance to assess the temporal dynamics of predation and effectiveness of defensive tactics in tropical forests.