scholarly journals Regulation of the neuroendocrine axis in male rats by soy-based diets is independent of age and due specifically to isoflavone action†

2020 ◽  
Vol 103 (4) ◽  
pp. 892-906
Author(s):  
Bamidele O Jeminiwa ◽  
Rachel M Knight ◽  
Tim D Braden ◽  
Crisanta Cruz-espindola ◽  
Dawn M Boothe ◽  
...  
Keyword(s):  
Control Diet ◽  
Diet Group ◽  
Male Rats ◽  
Receptor Protein ◽  
Subunit Protein ◽  
Beneficial Effects ◽  
Subunit Expression ◽  
Pituitary Glands ◽  
Neuroendocrine Axis

Abstract Soy-based foods are consumed for their health beneficial effects, implying that the population is exposed to soy isoflavones in the diet. Herein, male rats at 21, 35, and 75 days of age were maintained either on a casein control diet, soybean meal (SBM), or control diet supplemented with daidzin and genistin (G + D) for 14 days. Feeding of SBM and G + D diets decreased testicular testosterone (T) secretion regardless of age. Altered androgen secretion was due to decreased (P < 0.05) Star and Hsd17β protein in the testes and was associated with increased (P < 0.05) Lhβ and Fshβ subunit protein expression in pituitary glands. Second, male rats were fed either a casein control diet, control diet + daidzin, control diet + genistin, or control diet + genistin + daidzin (G + D). Compared to control, feeding of all isoflavone-containing diets decreased (P < 0.05) testicular T concentrations, and more so in the G + D diet group. Interestingly, Esr1 and androgen receptor protein and pituitary Fshβ with Lhβ subunit protein were increased (P < 0.05) by feeding of genistin and G + D diets, but not the daidzin diet. However, daidzein and genistein both caused a concentration dependent inhibition (P < 0.05) of T secretion by Leydig cells in vitro with IC50 of 184 ηM and 36 ηM, respectively. Results demonstrated that altered testicular steroidogenic capacity and pituitary FSHβ and LHβ subunit expression due to soy-based diets result from specific actions by genistein and daidzein. Experiments to assess effects of isoflavone regulation of intratesticular androgen concentrations on male fertility are warranted.

scholarly journals Persimmon-derived tannin ameliorates the pathogenesis of ulcerative colitis in a murine model through inhibition of the inflammatory response and alteration of microbiota

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Masahiro Kitabatake ◽  
Yoko Matsumura ◽  
Noriko Ouji-Sageshima ◽  
Tatsuki Nishioka ◽  
Atsushi Hara ◽  
...  
Keyword(s):  
Ulcerative Colitis ◽  
Immune Response ◽  
Murine Model ◽  
Control Diet ◽  
Antimicrobial Activities ◽  
Diet Group ◽  
Chronic Inflammatory Bowel Disease ◽  
Diospyros Kaki ◽  
Colon Inflammation

AbstractUlcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) induced by dysregulation of the immune response in the intestinal mucosa. Although the underlying mechanisms of UC development are not fully understood, disruption of gut microbiota, “dysbiosis”, is thought to lead to the development of IBD. Persimmon (Ebenaceae Diospyros kaki Thunb.)-derived tannin, which is a condensed polymeric tannin consisting of catechin groups, has antioxidant, anti-inflammatory, and antimicrobial activities. In this study, we assessed the effect of persimmon-derived tannin on a murine model of UC established by dextran sulfate sodium-induced colitis in female mice. Dietary supplementation of tannin significantly decreased disease activity and colon inflammation. A hydrolysate of tannin directly suppressed expression of inflammatory genes in macrophages in vitro. In faecal microbiota, the relative abundance of Bacteroides was increased significantly by tannin supplementation. Alpha-diversity indices in colitis-induced mice were significantly higher in the tannin diet group compared with the control diet group. Additionally, expansion of Enterobacteriaceae and Enterococcus, which is associated with disease progression of IBD, was remarkably suppressed in the tannin diet group. These results suggest that persimmon-derived tannin ameliorates colon inflammation in UC through alteration of the microbiota composition and immune response, which may be a promising candidate for IBD therapy.

BIOSYNTHESIS OF GONADOTROPHINS BY RAT PITUITARIES IN VITRO

1975 ◽  
Vol 66 (3) ◽  
pp. 369-374 ◽  
Author(s):  
MRIDULA CHOWDHURY ◽  
EMIL STEINBERGER
Keyword(s):  
Comparative Study ◽  
Anterior Pituitary ◽  
Male Rats ◽  
Leucine Incorporation ◽  
Experimental Conditions ◽  
Rat Pituitary ◽  
Pituitary Glands ◽  
Endogenous Proteases ◽  
Pituitary Homogenate

SUMMARY A method has been developed for studying biosynthesis of FSH in the rat pituitary in vitro. Anterior pituitary glands were incubated with [3H]leucine; a specific and sensitive immunoprecipitation technique was used to isolate FSH from the pituitary homogenate. Total FSH content of the samples was measured by a double-antibody radioimmunoassay technique. Using this technique, a comparative study of LH and FSH synthesis in the same pituitary of adult male rats incubated for various intervals (0·5–6 h) was done. Increased incorporation of [3H]leucine into both LH and FSH with time was noted. The rate and amount of [3H]leucine incorporation into FSH was found to be higher than that into LH, indicating that either the rate of FSH synthesis is higher than that of LH or FSH has more leucine residues than LH. Greater susceptibility of LH to degradation by endogenous proteases during dialysis may also reflect less incorporation of [3H]leucine into LH. This method provides a reliable tool for evaluating FSH synthesis under various experimental conditions.

INFLUENCE OF STEROID SEX HORMONES ON THE F. S. H.-RELEASE BY RAT HYPOPHYSES IN VITRO

1961 ◽  
Vol 36 (4) ◽  
pp. 485-497 ◽  
Author(s):  
G. P. van Rees
Keyword(s):  
Sex Hormones ◽  
Female Rats ◽  
Male Rats ◽  
Intact Female ◽  
Intact Male ◽  
Incubation Experiments ◽  
Rat Pituitary ◽  
Pituitary Glands ◽  
Steroid Sex Hormones

ABSTRACT The hypothesis that steroid sex hormones influence pituitary F. S. H. by independent actions on its production and capacity of the gland to release it has been investigated by means of incubation experiments. During incubation, rat pituitary glands released considerable amounts of F. S. H. into the medium. Inactivation of F. S. H. during incubation could not be demonstrated; once (in females) some production of F. S. H. was even observed. The amount of F. S. H. which is released into the medium is influenced by the quantity of F. S. H. stored in the hypophyses. Hypophyses from male rats pretreated with oestradiol released relatively more F. S. H. into the medium than hypophyses from control animals. On the other hand, pretreatment with testosterone caused the pituitary glands to release less F. S. H. into the medium. In agreement with these results, hypophyses from intact male rats released relatively less F. S. H. than hypophyses from intact female rats. These facts support the hypothesis that androgens depress pituitary F. S. H.-secretion by inhibiting the capacity to release it, while oestrogens, which can even promote this property of the pituitary gland, also act by directly inhibiting its production.

Postreceptorial refractoriness of prolactin release mechanisms

1983 ◽  
Vol 61 (7) ◽  
pp. 676-684 ◽  
Author(s):  
R. Collu ◽  
J. R. Ducharme ◽  
D. Eljarmak ◽  
A. M. Marchisio ◽  
J. Bertrand ◽  
...  
Keyword(s):  
Binding Sites ◽  
Immobilization Stress ◽  
Significant Rise ◽  
Male Rats ◽  
Plasma Prolactin ◽  
Initial Value ◽  
Prolactin Release ◽  
Pituitary Glands ◽  
Plasma Prl

Whilc a first injection of the antidopaminergic benzamide drug, sulpiride, induced a large rise in plasma prolactin (PRL) levels in chronically cannulated adult male rats, a second injection given 2 h later was totally inactive although the pituitary content of the hormone was still 76% of the initial value. When the second injection was given 8 h after the first it was slightly effective, but when administered 24 h later it was as effective as the first. The second of two consecutive injections of haloperidol given at 2-h intervals, or an injection of morphine given 2 h after sulpiride, were incapable of inducing a release of PRL. Two hours after an injection of sulpiride, a 30-min period of immobilization stress induced a significant rise in plasma PRL levels. A significant rise in plasma PRL levels was also observed when larger doses of sulpiride were given 2 h after a first injection of the drug. Apomorphine was at least as effective an inhibitor of PRL secretion when given 2 h after sulpiride than when injected after saline. In vitro studies of dopaminergic binding sites revealed the presence, in pituitary glands of sulpiride-treated rats, of receptors not modified by the drug. These data suggest that the only plausible explanation for the ineffectiveness of the second of two consecutive injections of sulpiride is the development of a state of refractoriness of the mechanisms that subserve the release of PRL induced by suppression of the inhibitory dopaminergic tonus.

Heterogeneity of rat FSH by chromatofocusing: studies on serum FSH, hormone released in vitro and metabolic clearance rates of its various forms [ill]

1985 ◽  
Vol 105 (1) ◽  
pp. 29-37 ◽  
Author(s):  
W. F. P. Blum ◽  
D. Gupta
Keyword(s):  
Molecular Size ◽  
Male Rats ◽  
Metabolic Clearance ◽  
Clearance Rates ◽  
Charged Species ◽  
Rat Pituitary ◽  
Isoelectric Points ◽  
Exclusion Chromatography ◽  
Pituitary Glands

ABSTRACT Rat pituitary FSH was fractionated by chromatofocusing between pH 6 and 3. Ten components were resolved having apparent isoelectric points between 3·1 and 5·1. A comparative study of pituitary FSH and FSH secreted in vitro by quartered pituitary glands in the presence and in the absence of gonadotrophin-releasing hormone (GnRH) revealed similar patterns of charged species of intracellular and released FSH. Although GnRH increased FSH secretion about fourfold, no influence on the pattern of charged species was observed. Utilizing exclusion chromatography and chromatofocusing, pituitary FSH was compared to serum FSH which had been extracted by immunoaffinity chromatography. The results demonstrate for serum FSH a larger molecular size and a relative shift to more acidic components. Metabolic clearance rates of eight FSH components separated by chromato-focusing were measured in adult male rats. Half-lives varied between 13 min and several hours. A correlation existed between decrease of isoelectric points and decrease of metabolic clearance rates. These findings suggest that (1) all hypophysial FSH components are secreted into the circulation at similar rates and (2) the more acidic FSH components which appear to contain increased sialic acid, have a longer circulatory half-life and are more abundant in serum. It is concluded that sialylation may be involved in modulating serum FSH levels. J. Endocr. (1985) 105, 29–37

scholarly journals Quercetin May Suppress Rat Aberrant Crypt Foci Formation by Suppressing Inflammatory Mediators That Influence Proliferation and Apoptosis

2008 ◽  
Vol 139 (1) ◽  
pp. 101-105 ◽  
Author(s):  
Cynthia A. Warren ◽  
Kimberly J. Paulhill ◽  
Laurie A. Davidson ◽  
Joanne R. Lupton ◽  
Stella S. Taddeo ◽  
...  
Keyword(s):  
Control Diet ◽  
Aberrant Crypt Foci ◽  
Male Rats ◽  
Preneoplastic Lesions ◽  
Proinflammatory Mediators ◽  
Proliferative Zone ◽  
Proliferation And Apoptosis ◽  
Cox 2 ◽  
Cox 1

Abstract The flavonoid quercetin suppresses cell proliferation and enhances apoptosis in vitro. In this study, we determined whether quercetin protects against colon cancer by regulating the protein level of phosphatidylinositol 3-kinase (PI 3-kinase) and Akt or by suppressing the expression of proinflammatory mediators [cyclooxygenase (COX)-1, COX-2, inducible nitric oxide synthase (iNOS)] during the aberrant crypt (AC) stage. Forty male rats were randomly assigned to receive diets containing quercetin (0 or 4.5 g/kg) and injected subcutaneously with saline or azoxymethane (AOM; 2 times during wk 3 and 4). The colon was resected 4 wk after the last AOM injection and samples were used to determine high multiplicity AC foci (HMACF; foci with >4 AC) number, colonocyte proliferation and apoptosis by immunohistochemistry, expression of PI 3-kinase (p85 and p85α subunits) and Akt by immunoblotting, and COX-1, COX-2, and iNOS expression by real time RT-PCR. Quercetin-fed rats had fewer (P = 0.033) HMACF. Relative to the control diet, quercetin lowered the proliferative index (P = 0.035) regardless of treatment and diminished the AOM-induced elevation in crypt column cell number (P = 0.044) and expansion of the proliferative zone (P = 0.021). The proportion of apoptotic colonocytes in AOM-injected rats increased with quercetin treatment (P = 0.014). Levels of p85 and p85α subunits of PI 3-kinase and total Akt were unaffected by dietary quercetin. However, quercetin tended to suppress (P < 0.06) the expression of COX-1 and COX-2. Expression of iNOS was elevated by AOM injection (P = 0.0001). In conclusion, quercetin suppresses the formation of early preneoplastic lesions in colon carcinogenesis, which occurred in concert with reductions in proliferation and increases in apoptosis. It is possible the effects on proliferation and apoptosis resulted from the tendency for quercetin to suppress the expression of proinflammatory mediators.

DISCREPANCY BETWEEN RADIOIMMUNOASSAY AND RADIOLIGAND-RECEPTOR ASSAY OF LUTEINIZING HORMONE RELEASED IN VITRO BY PITUITARY TISSUE FROM MALE RATS OF DIFFERENT AGES

1975 ◽  
Vol 65 (2) ◽  
pp. 265-273 ◽  
Author(s):  
R. M. SHARPE ◽  
M. SHAHMANESH ◽  
M. G. ELLWOOD ◽  
M. HARTOG ◽  
P. S. BROWN
Keyword(s):  
Luteinizing Hormone ◽  
Close Agreement ◽  
Male Rats ◽  
Male Rat ◽  
Receptor Assay ◽  
Pituitary Glands ◽  
Lh Release ◽  
Radioligand Receptor Assay ◽  
Lh Rh

SUMMARY Anterior pituitary glands from male rats aged 21, 40, 60 or 95 days were incubated in medium containing 0, 2 or 20 ng luteinizing hormone-releasing hormone (LH-RH)/ml. Incubates were assayed for LH by radioimmunoassay (RIA), by the radioligand-receptor assay (RLA) using testicular homogenates as the source of receptor and, in some instances, by the ovarian ascorbic acid depletion assay (OAAD). Irrespective of the dose of added LH-RH, glands from rats aged 40 and 60 days always showed a higher release of LH, as determined by RLA, than glands from animals aged 21 or 95 days. Measurement by RIA showed a similar pattern to RLA in the basal release of LH, but in the presence of LH-RH showed little difference in LH release by glands from rats aged 40, 60 or 95 days. The LH release caused by the higher concentration of LH-RH was always greater when measured by RLA than by RIA. Assay of comparable incubates by OAAD showed close agreement with RLA estimates in four incubations (mean index of discrimination 1·07; range 0·86–1·18) and consistent disagreement with RIA estimates (1·64; range 1·38–1·99). In contrast to the results with incubates, homogenates of pituitary glands from male rats of various ages showed close agreement of estimates by RLA, RIA and OAAD. These results suggest that RIA underestimates the LH-RH-stimulated release of LH in vitro from the male rat pituitary during some stages of sexual maturation.

scholarly journals Fish-bone peptide increases calcium solubility and bioavailability in ovariectomised rats

2006 ◽  
Vol 95 (1) ◽  
pp. 124-128 ◽  
Author(s):  
Won-Kyo Jung ◽  
Bae-Jin Lee ◽  
Se-Kwon Kim
Keyword(s):  
Bone Mineral ◽  
Control Diet ◽  
Experimental Period ◽  
Fish Bone ◽  
High Ratio ◽  
Diet Group ◽  
Mineral Density ◽  
Ovariectomised Rats

Fish-bone peptides (FBP) with a high affinity to Ca were isolated using hydroxyapatite affinity chromatography, and FBP II with a high ratio of phosphopeptide was fractionated in the range of molecular weight 5·0–1·0kDa by ultramembrane filtration.In vitrostudy elucidated that FBP II could inhibit the formation of insoluble Ca salts in neutral pH.In vivoeffects of FBP II on Ca bioavailability were further examined in the ovariectomised rat. During the experimental period, Ca retention was increased and loss of bone mineral was decreased by FBP II supplementation in ovariectomised rats. After the low-Ca diet, the FBP II diet, including both normal level of Ca and vitamin D, significantly decreased Ca loss in faeces and increased Ca retention compared with the control diet. The levels of femoral total Ca, bone mineral density, and strength were also significantly increased by the FBP II diet to levels similar to those of the casein phosphopeptide diet group (no difference;P>0·05). In the present study, the results proved the beneficial effects of fish-meal in preventing Ca deficiency due to increased Ca bioavailability by FBP intake

INHIBITION OF STEROID 5α-REDUCTASE IN VIVO: EFFECT ON SUPPRESSION OF LUTEINIZING HORMONE AND STIMULATION OF ACCESSORY SEX ORGANS BY TESTOSTERONE IN THE ORCHIDECTOMIZED RAT

1979 ◽  
Vol 81 (2) ◽  
pp. 209-220 ◽  
Author(s):  
LIDIA WEI LIU KAO ◽  
JUDITH WEISZ
Keyword(s):  
Prostate Gland ◽  
Male Rats ◽  
Ventral Prostate ◽  
Promoting Effect ◽  
Accessory Sex Organs ◽  
Pituitary Glands ◽  
Lh Secretion ◽  
Carboxylic Acid Derivative

An inhibitor of 5α-reductase, the 17β-carboxylic acid derivative of testosterone (testosterone-17βCA), has been used to evaluate the importance of the 5α-reduction of testosterone in its action on the suppression of LH secretion in male rats. The potential of testosterone-17βCA to inhibit the formation of 5α-dihydrotestosterone (DHT) was first demonstrated in vitro. When homogenates of hypothalami or anterior pituitary glands were incubated with [3H]testosterone in the presence of a 50-fold excess of testosterone-17βCA, the formation of labelled DHT was inhibited by more than 80%. Adult male rats that had been castrated for 1–2 months were fitted with chronic intravenous catheters and implanted with silicone elastomer sheets: one group received one sheet, 0·5–2·0 cm2 in size containing 1·6% testosterone, a second group received one 50 cm2 sheet containing 1·6% testosterone-17βCA and a third group received two sheets, one sheet 50 cm2 in size containing 1·6% testosterone-17βCA and the second ranging in size from 0·5 to 2·0 cm2 and containing 1·6% testosterone. Blood was withdrawn daily from each rat over a 4–5 day period after implantation of the steroids and the level of LH in the plasma was measured by radioimmunoassay. The seminal vesicles and the ventral prostate gland were removed at autopsy on day 4 or 5; the weights of these organs were shown to have increased progressively as the size of the implant of testosterone increased. In contrast, the level of LH in the plasma was suppressed to a comparable extent by implants of testosterone between 0·6 and 2 cm2, whereas a 0·5 cm2 implant of testosterone had no effect. Implants of testosterone-17βCA alone did not influence the weight of the accessory organs or the level of LH. When testosterone-17βCA and testosterone were implanted together, the growth-promoting effect of the latter on the accessory sex organs was significantly reduced. The effectiveness of testosterone in suppressing the level of LH in the plasma of these animals was not influenced by the presence of testosterone-17βCA and in certain instances the level was raised.

scholarly journals Comprehensive miRNA and DNA Microarray Analyses Reveal the Response of Hepatic miR-203 and Its Target Gene to Protein Malnutrition in Rats

Genes ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 75
Author(s):  
Kaoru Takahashi ◽  
Huijuan Jia ◽  
Shoko Takahashi ◽  
Hisanori Kato
Keyword(s):  
Fatty Acids ◽  
Dna Microarray ◽  
Control Diet ◽  
Mrna Level ◽  
Protein Malnutrition ◽  
Protein Diet ◽  
Male Rats ◽  
Low Protein Diet ◽  
Low Protein

Adequate protein nutrition is essential for good health. Effects of protein malnutrition in animals have been widely studied at the mRNA level with the development of DNA microarray technology. Although microRNAs (miRNAs) have attracted attention for their function in regulating gene expression and have been studied in several disciplines, fewer studies have clarified the effects of protein malnutrition on miRNA alterations. The present study aimed to elucidate the relationship between protein malnutrition and miRNAs. Six-week old Wistar male rats were fed a control diet (20% casein) or a low-protein diet (5% casein) for two weeks, and their livers were subjected to both DNA microarray and miRNA array analysis. miR-203 was downregulated and its putative target Hadhb (hydroxyacyl-CoA dehydrogenase β subunit), known to regulate β-oxidation of fatty acids, was upregulated by the low-protein diet. In an in vitro experiment, miR-203 or its inhibitor were transfected in HepG2 cells, and the pattern of Hadhb expression was opposite to that of miR-203 expression. In addition, to clarifying the hepatic miRNA profile in response to protein malnutrition, these results showed that a low-protein diet increased Hadhb expression through downregulation of miR-203 and induced β-oxidation of fatty acids.

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