Study of the fate of phyto-oestrogens in the sheep by determination of isoflavones and coumestrol in the plasma and adipose tissue

1967 ◽  
Vol 18 (2) ◽  
pp. 305 ◽  
Author(s):  
HR Lindner

A method is presented for the specific determination in plasma or adipose tissue of sheep of the phyto-oestrogens genistein (G), biochanin A (BA), formononetin (F), daidzein (D), pratensein, and coumestrol. The method is based on selective extraction, paper chromatography, spectrophotometry and fluorometry, and use of radioactive recovery standards. A modification including gas chromatography is also described. Intraruminal administration to sheep of the synthetic isoflavones G, BA, or F gave rise within 2½ hr to detectable blood levels of the compound infused. In addition, intraruminal administration of BA and F was followed by the appearance of G and D, respectively, in blood and fat depots. Such O-demethylation at the C4 position was also observed after intramuscular injection of BA or F, and in sheep grazing subterranean clover (Trifolium subterraneum L.) and red clover (T. pratense). Plasma levels of free G above 5 µg/100 ml (excluding circulating isoflavone conjugated as glucuronide) were associated with maximal uterine growth response in ovariectomized ewes, while levels of 1–5 µg/100 ml appeared to elicit a graded uterine response; free plasma F and D levels above 0.5 �g/100 ml seem to be required for detectable uterotrophic action in the 5-day assay used. G, BA, F, and D were present in the plasma of sheep grazing subterranean clover var. Yarloop in concentrations adequate to explain the observed uterine growth response, but in sheep grazing red clover, the plasma levels seemed too low to account fully for the oestrogenic action of this pasture. No free isoflavones were detected in plasma from sheep grazing subterranean clover var. Marrar, despite the high isoflavone content of the pasture.

1967 ◽  
Vol 18 (4) ◽  
pp. 647 ◽  
Author(s):  
DA Shutt ◽  
A Axelsen ◽  
HR Lindner

The plasma of sheep grazing various species of oestrogenic clover contained water-soluble conjugates of daidzein, formononetin, genistein, and biochanin A, chiefly in the form of glucuronides, in concentrations up to 40 µg/100 ml. In sheep pen-fed on red clover or subterranean clover (cv. Dinninup and Yarloop) the total concentration of these four isoflavones 3–5 hr after feeding ranged from 150 to 720 µg/100 ml plasma, of which 1–2% only was present in "free" (i.e. unconjugated) form; by 24 hr the plasma level had fallen to < 5 µg/100 ml plasma. Preconditioning the pen-fed sheep to oestrogenic clover, or adding lucerne to the diet, had no significant effect on the concentration of "free" or conjugated isoflavones in the plasma and had no inhibitory effect on the uterine weight response. Comparison of the composition of circulating isoflavones to that of the clover ingested indicated partial demethylation of formononetin to daidzein and of biochanin A to genistein, and suggested that genistein and biochanin A were degraded more rapidly than formononetin or daidzein in the sheep. Equol, a metabolite previously isolated from the urine of sheep treated with formononetin, was present in the plasma at a concentration of 50–170 µg/100 ml 24 hr after feeding.


1955 ◽  
Vol 6 (4) ◽  
pp. 456 ◽  
Author(s):  
WH Southcott

Field trials in 1951 and 1952 confirmed previous observations on the evacuation of adult Oesophagostomum columbianum Curtice from sheep which graze continuously on green oats. Ingestion of phalaris-subterranean clover or red clover pasture also resulted in the evacuation of some O. columbianum but was much less effective in this regard. Evacuation of O. columbianum from sheep on green oats was not complete and was associated with softening, and lowering of the pH, of the faeces. The phenomenon occurred both with and without a considerable increase in liveweight. Some of the factors associated with oat-grazing which may influence removal of O. columbianum are discussed.


1970 ◽  
Vol 21 (5) ◽  
pp. 713 ◽  
Author(s):  
DA Shutt ◽  
RH Weston ◽  
JP Hogan

Studies have been made of the digestion and metabolism in Merino wethers of the isoflavones in subterranean clover (Trtfolium subterraneurn cv. Clare) and red clover (T. pratense). The dietary intake of isoflavones with both clovers was about 9 g per day. With the subterranean clover, the isoflavones were predominantly genistein and biochanin A, and slight teat length increases in the wethers ingesting this clover indicated a low level of oestrogenicity. With the red clover formononetin represented 60% of the isoflavone present and the wethers on this diet exhibited maximal teat length increases indicating a high level of oestrogenicity. Less than 1 % of the daily intake of the isoflavones was excreted as such in the faeces and urine; hence most of these compounds were metabolized or retained in the sheep. The dietary isoflavones were found to disappear rapidly from the rumen, and it was estimated by using marker techniques that the removal of these compounds from the stomach (rumen, reticulum, omasum, and abomasum) was virtually complete. Equol (7,4'-dihydroxyisoflavan), a metabolite of formononetin, was the predominant phyto-oestrogen in the digesta and excreta when red clover was given. The excretion of 3.9 g/day of this compound, mainly in urine, was equivalent to 70% of the intake of formononetin. It was calculated that about 86% of the equol produced in the rumen was absorbed from that organ; the mean residence time for equol in the rumen was estimated to be 1.7 hr. The isoflavones were present in blood plasma mainly in conjugated forms. Equol predominated with both clovers. The levels of equol were much lower with the subterranean clover than with the red clover diet; the concentrations of the conjugated form were respectively 13 and 300-440 �g/100 ml. Equol in the free form, although not detectable with the subterranean clover, was present at 4-10 �g/100 ml with red clover. The data were considered to be consistent with the conclusion that equol accounts for most of the phyto-oestrogenic activity in sheep fed on clovers containing high levels of formononetin.


1984 ◽  
Vol 24 (126) ◽  
pp. 322 ◽  
Author(s):  
PT Kenny ◽  
KFM Reed

The productivity of weaner sheep grazing lucerne, white clover, red clover or Persian clover and pastures sown with subterranean clover and perennial ryegrass, cocksfoot or tall fescue, was measured in summer-autumn trials incorporating four soil types in each of three years. During summer and autumn, the mean growth rate of sheep grazing lucerne, white clover or Persian clover pastures was 50 g/d compared with 1 g/d for sheep grazing perennial grass-subterranean clover pastures. Sheep grazing strawberry clover on reclaimed swampland, and sheep in a feedlot (fed hay and lupin grain) averaged 100 and 75 g/d, respectively. Sheep grazing red clover averaged 45 g/d over years 1 and 2. In year 2, a subterranean clover-dominant pasture was included in the study. Its feeding value was similar to that of the perennial grass-subterranean clover pastures. Sheep grazing legume pastures, and sheep in the feedlot, consistently produced more wool (up to 700 g/head) than sheep grazing the perennial grass-subterranean clover pastures. The concentration of neutral detergent fibre in herbage from legume pastures was frequently lower (P< 0.05) and the concentration of crude protein was frequently higher (P< 0.05) than in herbage from grass pastures. The dry matter digestibility of legume herbage was higher (P<0. 05) than that of grass herbage on only one occasion. Measurements of crude protein and neutral detergent fibre of pasture in December accounted for 67% of the variation in liveweight gain (P<0.01). Ewe weaners grazing red clover pasture exhibited an increase (P< 0.05) in teat length of 3.9 mm in 21d of grazing. Oestrous activity of ewe weaners was related to liveweight gain (r = 0.77). The implications of the results for agricultural systems are discussed.


2006 ◽  
Vol 1 (7) ◽  
pp. 1934578X0600100 ◽  
Author(s):  
Aldo Tava ◽  
Luciano Pecetti ◽  
Alessia Bertoli ◽  
Efisio Piano

A collection of subterranean clover (Trifolium subterraneum L.) genotypes from Sardinia was evaluated for the content of oestrogenic isoflavones to assess differences in total and individual compounds. Daidzein, genistein, and their respective 4′-methoxy derivatives biochanin A and formononetin, were detected in leaves and quantified by GC/FID and GC/MS methods. A large variation among genotypes for individual compounds and for the total isoflavone concentration was observed. Total isoflavones were measured in the range 0.8-13.4 mg/g fresh weight (0.3-4.5% dry matter). Daidzein was usually present in lower amount compared to the other isoflavones. Genistein and biochanin A were found in most cases in higher concentration than formononetin. Phyto-oestrogens have been shown to have both oestrogenic and anti-oestrogenic properties, and their effects entail a positive role for the human health. T. subterraneum revealed the presence of higher concentration of isoflavones compared to other sources of these compounds, e.g. soybean (Glycine max (L.) Merrill) and red clover (Trifolium pratense L.). This study provided information on the biodiversity of the natural strains from Sardinia, emphasizing the importance of these genetic resources for their variation in the amount of total and individual isoflavones.


1971 ◽  
Vol 24 (7) ◽  
pp. 1509 ◽  
Author(s):  
AB Beck ◽  
JR Knox

Formononetin and biochanin A 7-O-glucosides (1a and 2a) and their malonate hemi-ester derivatives (1b and 2b) have been isolated from red clover and from the Yarloop strain of subterranean clover. Structure (2b) is a correction of an earlier structural assignment to this compound. Small amounts of the derived methyl esters (1c and 2c) are also present in both clovers. Similar derivatives of genistein have been obtained from the Yarloop strain, although only the 7-O-glucoside (3a) has been isolated in pure form. Studies on red clover and on nine strains of subterranean clover have demonstrated in all cases that the acidic malonate esters account for the predominant proportion of the glycosides.


1971 ◽  
Vol 22 (4) ◽  
pp. 663 ◽  
Author(s):  
AWH Braden ◽  
RI Thain ◽  
DA Shutt

Wethers and heifers were fed on freshly cut pasture (red clover, Mt. Barker or Tallarook subterranean clover, or ryegrass) and the blood plasma concentration of the phyto-oestrogens and their metabolites estimated 5 hr, 24 hr, and 6 days after the beginning of the feeding. The heifers were allowed to graze the pastures after the first day. On the basis of increase in teat length in the wethers, red clover and Tallarook were estimated to have equivalent oestrogenicity ; Mt. Barker was much less active. Qualitatively, the metabolism of formononetin and biochanin A appeared similar in the two species, but there was evidence that the rates of metabolism and of conjugation were faster in cattle than in sheep. The findings are discussed in relation to an infertility syndrome in dairy cattle.


Author(s):  
R.J.M. Hay ◽  
D.L. Ryan

In a series of trials at Grasslands Gore, over 10 years, the late-flowering tetraploid red clover 'Grassland Pawera' was more productive and persistent than other red clover cultivars. The strong summer growth of Pawera meets the need for heavy-weight lamb feed and high quality forage for conservation in intensive sheep farming systems in Southland. Lenient. infrequent defoliation is necessary to maximise DM production and persistence of Pawera. The most compatible of the grasses evaluated was 'Grasslands Roa' tall fescue. However, 'Grasslands Nui' ryegrass will still be the major grass sown with Pawera owing to its widespread acceptance. In ryegrass mixtures, sowing rates of 5-7 kg/ha of red clover were needed to optimise establishment and subsequent yield. Evidence of oestrogenic activity of Pewera to sheep prompted Grasslands Division to select within Pawera for a low formononetin cultivar. Keywords: red clover, Pawera. Hamua, Turoa. G21. G22, G27. oestrogenic activity, Nui ryegrass, Roa tall fescue, Maru phalaris. Southland, sheep grazing, frequency, intensity, quality. seasonal growth


Antioxidants ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1210
Author(s):  
Amy K. Hauck ◽  
Tong Zhou ◽  
Ambuj Upadhyay ◽  
Yuxiang Sun ◽  
Michael B. O’Connor ◽  
...  

Oxidative stress is a hallmark of metabolic disease, though the mechanisms that define this link are not fully understood. Irreversible modification of proteins by reactive lipid aldehydes (protein carbonylation) is a major consequence of oxidative stress in adipose tissue and the substrates and specificity of this modification are largely unexplored. Here we show that histones are avidly modified by 4-hydroxynonenal (4-HNE) in vitro and in vivo. Carbonylation of histones by 4-HNE increased with age in male flies and visceral fat depots of mice and was potentiated in genetic (ob/ob) and high-fat feeding models of obesity. Proteomic evaluation of in vitro 4-HNE- modified histones led to the identification of both Michael and Schiff base adducts. In contrast, mapping of sites in vivo from obese mice exclusively revealed Michael adducts. In total, we identified 11 sites of 4-hydroxy hexenal (4-HHE) and 10 sites of 4-HNE histone modification in visceral adipose tissue. In summary, these results characterize adipose histone carbonylation as a redox-linked epigenomic mark associated with metabolic disease and aging.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Maryam Ebadi ◽  
Vera C. Mazurak

Fat loss is associated with shorter survival and reduced quality of life in cancer patients. Effective intervention for fat loss in cachexia requires identification of the condition using prognostic biomarkers for early detection and prevention of further depletion. No biomarkers of fat mass alterations have been defined for application to the neoplastic state. Several inflammatory cytokines have been implicated in mediating fat loss associated with cachexia; however, plasma levels may not relate to adipose atrophy. Zinc-α2-glycoprotein may be a local catabolic mediator within adipose tissue rather than serving as a plasma biomarker of fat loss. Plasma glycerol and leptin associate with adipose tissue atrophy and mass, respectively; however, no study has evaluated their potential as a prognostic biomarker of cachexia-associated fat loss. This review confirms the need for further studies to identify valid prognostic biomarkers to identify loss of fat based on changes in plasma levels of biomarkers.


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