Impact of heat stress and a feed supplement on hormonal and inflammatory responses of dairy cows.

The aim of this trial was to evaluate the effects of an immunomodulatory supplement (OmniGen AF, OG; Phibro Animal Health Corp.) and heat stress on hormonal, inflammatory, and immunological responses of lactating dairy cows. Sixty multiparous Holstein cows were randomly assigned to 4 treatments in a 2 × 2 factorial arrangement using 2 environments: cooled using fans and misters, or noncooled, and 2 top-dressed feed supplements (56 g/d): OG or a placebo (CTL). Temperature-humidity index averaged 78 during the 8-wk trial. Blood was drawn to analyze cortisol, prolactin, and circulating tumor necrosis factor (TNF)-α and IL-10. Peripheral blood mononuclear cells (PBMC) were isolated and stimulated with hydrocortisone, prolactin, or lipopolysaccharide (LPS), individually or in several combinations, to assess induced proliferation and cytokine production. At d 52, 6 cows per treatment were injected i.v. with an LPS bolus (ivLPS) to assess hormone and cytokine responses. For cooled cows, feeding OG increased plasma cortisol concentration relative to CTL. Noncooled cows fed CTL had lower circulating TNF-α concentrations than noncooled-OG and cooled-CTL cows, with cooled-OG intermediate. Hydrocortisone+LPS-stimulated PBMC from OG cows tended to proliferate more than CTL. Relative to cooled cows, PBMC from noncooled cows produced more TNF-α and IL-10 when stimulated with LPS. Following ivLPS, cooled-OG cows had a greater cortisol response than the other treatments. In conclusion, OG supplementation enhanced cortisol release under basal condition and induced inflammation with cooling compared with CTL. This suggests that heat stress inhibits OG-mediated cortisol release. Heat stress seemed to enhance the inflammatory responses of PBMC from lactating cows. However, OG supplementation promoted PBMC proliferation under stress, or in the presence of hydrocortisone.

Quercetin attenuates cisplatin-induced fat loss.

PURPOSE: The major aim of the present study was to determine the effects of quercetin, a well-known flavonoid, on attenuating cisplatin (CDDP)-induced fat loss and the possible mechanisms. METHODS: Tumor-bearing nude mice and tumor-free BALB/c mice were administrated with CDDP alone or in combination with quercetin by a diet containing 0.1% or 1% quercetin (LQ or HQ) or by intraperitoneal injection (IQ) to determine the effects of quercetin on the anticancer effect of CDDP or CDDP-induced fat loss. The effects of quercetin on fat accumulation in CDDP-exposed 3T3-L1 cells were also determined. RESULTS: We first showed that HQ and IQ significantly enhanced the anticancer effect of CDDP by upregulating p53- and p21-associated pathways, while tended to attenuate CDDP-induced fat loss in tumor-bearing nude mice. The study in 3T3-L1 cells showed that CDDP decreased the fat accumulation accompanied by strong upregulation of the expression of six genes which are associated with fat metabolism, while quercetin completely suppressed such an effect. The tumor-free BALB/c mice study consistently showed a protective effect of HQ on CDDP-induced body weight and epididymal fat loss. HQ also increased the fat levels in liver and muscle tissues. In epididymal fat tissues, HQ consistently attenuated CDDP-induced changes in fat metabolism-associated gene expression. However, CDDP alone or in combination with HQ did not affect the food intake. CONCLUSIONS: This study demonstrates that quercetin possesses the potential to suppress CDDP-induced fat loss may partly through the regulation of the fat metabolism-associated gene expression.

An engineered pathway for N-hydroxy-pipecolic acid synthesis enhances systemic acquired resistance in tomato.

Systemic acquired resistance (SAR) is a powerful immune response that triggers broad-spectrum disease resistance throughout a plant. In the model plant Arabidopsis thaliana, long-distance signaling and SAR activation in uninfected tissues occur without circulating immune cells and instead rely on the metabolite N-hydroxy-pipecolic acid (NHP). Engineering SAR in crop plants would enable external control of a plant's ability to mount a global defense response upon sudden changes in the environment. Such a metabolite-engineering approach would require the molecular machinery for producing and responding to NHP in the crop plant. Here, we used heterologous expression in Nicotiana benthamiana leaves to identify a minimal set of Arabidopsis genes necessary for the biosynthesis of NHP. Local expression of these genes in tomato leaves triggered SAR in distal tissues in the absence of a pathogen, suggesting that the SAR trait can be engineered to enhance a plant's endogenous ability to respond to pathogens. We also showed tomato produces endogenous NHP in response to a bacterial pathogen and that NHP is present across the plant kingdom, raising the possibility that an engineering strategy to enhance NHP-induced defenses could be possible in many crop plants.

Characterization of a lily anther-specific gene encoding cytoskeleton-binding glycoproteins and overexpression of the gene causes severe inhibition of pollen tube growth.

This work characterizes an anther/pollen-specific gene that encodes potential intermediate filament (IF)-binding glycoproteins in lily (Lilium longiflorum Thunb. cv. Snow Queen) anthers during the development and pollen germination. LLP13 is a single gene that encodes a polypeptide of 807 amino acids, and a calculated molecular mass of 91 kDa. The protein contains a predicted transmembrane domain at the N-terminus and a conserved domain of unknown function (DUF)593 at the C-terminal half of the polypeptide. Sequence analysis revealed that LLP13 shares significant identity (37-41 %) with two intermediate filament antigen-binding proteins, representing a unique subgroup of DUF593 domain proteins from known rice and Arabidopsis species. The expression of LLP13 gene is anther-specific, and the transcript accumulates only at the stage of pollen maturation. Both premature drying and abscisic acid (ABA) treatment of developing pollen indicated that LLP13 was not induced by desiccation and ABA, but by other developmental cues. Antiserum was raised against the overexpressed LLP13C fragment of the protein in Escherichia coli and affinity-purified antibodies were prepared. Immunoblot analyses revealed that the LLP13 protein was a heterogeneous, anther-specific glycoprotein that accumulated only at the stage of pollen maturation. The protein is not heat-soluble. The level of LLP13 protein remained for 24 h during germination in vitro. Overexpression of LLP13-GFP or GFP-LLP13 in lily pollen tubes caused severe inhibition of tube elongation. The LLP13 protein codistributed with mTalin in growing tubes, suggesting that it apparently decorates actin cytoskeleton and is likely a cytoskeleton-binding protein that binds with IFs that potentially exist in pollen tubes.

Parallel screening of wild-type and drug-resistant targets for anti-resistance neuraminidase inhibitors.

Infection with influenza virus is a major public health problem, causing serious illness and death each year. Emergence of drug-resistant influenza virus strains limits the effectiveness of drug treatment. Importantly, a dual H275Y/I223R mutation detected in the pandemic influenza A 2009 virus strain results in multidrug resistance to current neuraminidase (NA) drugs. Therefore, discovery of new agents for treating multiple drug-resistant (MDR) influenza virus infections is important. Here, we propose a parallel screening strategy that simultaneously screens wild-type (WT) and MDR NAs, and identifies inhibitors matching the subsite characteristics of both NA-binding sites. These may maintain their potency when drug-resistant mutations arise. Initially, we analyzed the subsite of the dual H275Y/I223R NA mutant. Analysis of the site-moiety maps of NA protein structures show that the mutant subsite has a relatively small volume and is highly polar compared with the WT subsite. Moreover, the mutant subsite has a high preference for forming hydrogen-bonding interactions with polar moieties. These changes may drive multidrug resistance. Using this strategy, we identified a new inhibitor, Remazol Brilliant Blue R (RB19, an anthraquinone dye), which inhibited WT NA and MDR NA with IC(50) values of 3.4 and 4.5 µM, respectively. RB19 comprises a rigid core scaffold and a flexible chain with a large polar moiety. The former interacts with highly conserved residues, decreasing the probability of resistance. The latter forms van der Waals contacts with the WT subsite and yields hydrogen bonds with the mutant subsite by switching the orientation of its flexible side chain. Both scaffolds of RB19 are good starting points for lead optimization. The results reveal a parallel screening strategy for identifying resistance mechanisms and discovering anti-resistance neuraminidase inhibitors. We believe that this strategy may be applied to other diseases with high mutation rates, such as cancer and human immunodeficiency virus type 1.

Three-dimensional arrayed amino aerogel biochips for molecular recognition of antigens.

The three-dimensional (3D) biochips prepared in this study are composed of a glass microscopy slide arrayed with amino aerogel dots. The amino aerogel was produced using the sol-gel process, with an ionic liquid as the template followed by a solvent extraction to remove the template and build a three-dimensional mesoporous structure. The FTIR spectrum verified that the major template was removed and the (29)Si solid-state NMR spectra recognized the cross-linkages in the SiO(2) network structure. SEM images measured the particles at around 100 nm. After grinding, the BET analysis confirmed that the nano-size amino aerogel powders had exhibited specific surface area of 188 m(2)/g, pore volume of 0.83 cm(3)/g, and average pore size of 16.2 nm. The as-prepared amino aerogel surface contained amino functional groups capable of performing a sandwich immunoassay. The primary antibody was immobilized on the internal surface of the arrayed amino aerogel to capture its affinity antigen. On the top of the captured antigen, the report antibody was read its labeling fluorescent dye. In comparison to the corresponding two-dimensional (2D) biochip, the 3D amino aerogel biochips were observed to amplify signal intensities more effectively due to their remarkable capturing capability.