ALBERT

Description: Cafestol overcomes ABT-737 resistance in Mcl-1-overexpressed renal carcinoma Caki cells through downregulation of Mcl-1 expression and upregulation of Bim expression Cell Death and Disease 5, e1514 (November 2014). doi:10.1038/cddis.2014.472 Authors: S M Woo, K-j Min, B R Seo, J-O Nam, K S Choi, Y H Yoo & T K Kwon

Description: Antipsychotic agent thioridazine sensitizes renal carcinoma Caki cells to TRAIL-induced apoptosis through reactive oxygen species-mediated inhibition of Akt signaling and downregulation of Mcl-1 and c-FLIP(L) Cell Death and Disease 5, e1063 (February 2014). doi:10.1038/cddis.2014.35 Authors: K-j Min, B R Seo, Y C Bae, Y H Yoo & T K Kwon

Description: In situ and in vitro rumen incubations were used to determine the effect of condensed tannins (CT) on the solubilization and degradation of the plant protein from white clover (Trifolium repens) and Lotus corniculatus. These forages contained, respectively 0·3 and 22·1 g CT/kg dry matter (DM). The sheep used for the experiments were also fed either white clover or L. corniculatus. Effects of CT were determined by making measurements in the presence and absence of polyethylene glycol (PEG; molecular weight 3500), which binds and inactivates CT. The loss of DM, neutral detergent fibre (NDF), total nitrogen (N) and Rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase; EC 4.1.1.39; fraction I leaf protein) from polyester bags suspended in the rumen of sheep was measured. The loss of these constituents from polyester bags suspended in the rumen was used as a measurement of their solubilization. Degradation was defined as the disappearance of Rubisco from white clover and L. corniculatus added to in vitro incubations with rumen fluid obtained from the same fistulated sheep fed either white clover or L. corniculatus.In the absence of PEG, the in situ loss of Rubisco from L. corniculatus was less rapid than the loss of this protein from white clover when each forage was incubated in the rumen of sheep fed the same diet. Addition of PEG tended to increase the loss of Rubisco from L. corniculatus, suggesting that CT slowed the rates of solubilization of Rubisco from this forage. Effects of rumen fluid were small, but there was some evidence that the rumen fluid in sheep fed L. corniculatus reduced the solubilization of Rubisco from white clover. The action of CT did not inhibit the in situ loss of NDF from either white clover or L. corniculatus.In the absence of PEG, the in vitro degradation of Rubisco from L. corniculatus was slower when compared to the degradation of this protein from white clover; PEG addition increased the degradation of Rubisco from L. corniculatus, but not from white clover, showing that CT was the causal agent. The addition of CT extracted from L. corniculatus markedly depressed the degradation of Rubisco from white clover, with the effect being completely reversible by PEG. The large subunit (LSU) of Rubisco was consistently degraded at a faster rate than the small subunit (SSU) and added CT had a greater effect in slowing the degradation of the LSU compared to the SSU. There was little difference in the degradation of Rubisco when rumen fluid from sheep fed either white clover or L. corniculatus was used for in vitro incubations.It was concluded that the action of CT from L. corniculatus reduces the digestion of protein in the rumen of sheep. This effect is predominantly due to the action of CT reducing the degradation of plant protein, although CT also reduced the solubilization of plant protein. The main effects of CT on protein solubilization and degradation seemed to be produced locally by CT present in plant tissue; transfer of these effects through rumen fluid was small in magnitude.

Description: A grazing experiment, conducted for 55 days (from 4 March to 29 April) in the late summer/autumn of 1997, at Massey University, Palmerston North, New Zealand, compared the reproductive efficiency and wool growth of ewes grazing Lotus corniculatus (birdsfoot trefoil) or perennial ryegrass (Lolium perenne)/white clover (Trifolium repens) dominant pasture (pasture). Half the ewes grazing each forage were given daily oral polyethylene glycol (PEG: molecular weight 3500) supplementation to inactivate the condensed tannins (CT) in lotus. A rotational grazing system with 200 mixed age ewes (54·2±0·88 kg/ewe; 50 ewes/treatment) was used.The effect of forage species and PEG supplementation upon voluntary feed intake (VFI), concentration of plasma metabolites, reproductive efficiency, wool production and wool characteristics was measured during two synchronized oestrous cycles. The ewes were restricted to maintenance feeding for the first 12 days of each oestrous cycle and then increased to ad libitum for the 6 days prior to and including ovulation. Lotus contained 17 g total CT/kg dry matter (DM) in the diet selected. There were only trace amounts of total CT in pasture. In vitro organic matter digestibility (OMD) was higher for lotus (0·82 v. 0·74) than for pasture, whilst lotus contained less nitrogen (N; 37·8 v. 44·5 g/kg OM).Mean ovulation rates (OR) for CT-acting and PEG sheep grazing pasture and lotus were respectively 1·33 v. 1·35 and 1·78 v. 1·56, with corresponding lambing percentages being 1·36 v. 1·36 and 1·70 v. 1·42. Fecundity (number of corpora lutea/ewe ovulating) was greater for ewes grazing lotus than pasture (P