Effects of Diets Enriched in Linseed and Fish Oil on the Expression Pattern of Toll-Like Receptors 4 and Proinflammatory Cytokines on Gonadal Axis and Reproductive Organs in Rabbit Buck.

Infections of the genital tract can perturb the fertility in humans and animals. Pathogen recognition and activation of innate immunity onset through the pattern recognition receptor activation, such as Toll-like receptor 4 (TLR4), leading to the production of proinflammatory cytokines and mediators. TLR4 is expressed both on leukocytes and nonimmune cells. Rabbit TLR4 shows great similarity to its human counterpart. Moreover, the TLR4 signalling pathway could be modulated by long-chain polyunsaturated fatty acids (LC-PUFA). The objectives of this study were (i) to determine the expression levels of TLR4 and proinflammatory cytokines in the reproductive hypothalamic-gonadal axis of the male rabbit and (ii) to evaluate if the n-3 PUFA-enriched diets can modify their expression levels in the tissues and LC-PUFA profiles in seminal plasma. Fifteen rabbit bucks (n = 5/experimental group) were fed with different diets: commercial standard (group C), rich in extruded linseed (10%, group L), and in fish oil (3%, group FO) for 110 days. TLR4, TNF-α, and IL-1ß mRNA were ubiquitously expressed throughout the hypothalamic-gonadal axis. However, TLR4 mRNA expression was lower in the hypothalamus than the epididymis (P < 0.01), seminal vesicles (P < 0.01), and pituitary gland (P < 0.05). Dietary enrichment in PUFA did not modify the gene expression profile nor the histological characteristics of the tissues. Conversely in seminal plasma, rabbits fed with L and FO had lower n-6 (P < 0.05), LC-PUFA n-6 (P < 0.05), and n-6/n-3 ratio (P < 0.05) but higher n-3 (P < 0.001) and LC-PUFA n-3 (P < 0.01) compared to the control group. Our study builds a map of the gene expression of TRL4 and proinflammatory cytokines in the reproductive hypothalamic-gonadal axis of the male rabbit, fundamental step for understanding the immune defence mechanisms. Diets enriched in LC-PUFA did not affect basal gene expression but modulated sperm fatty acid composition. Finally, rabbit may be an excellent animal model to study the relationship between inflammation and infertility, and the nutritional modulation of immune functions.

Prostate Cancer Antigen 3 Score Does Not Predict for Adverse Pathologic Features at Radical Prostatectomy or for Progression-free Survival in Clinically Localized, Intermediate- and High-risk Prostate Cancer.

OBJECTIVE: To evaluate whether preoperative urinary prostate cancer antigen 3 (PCA3) scores predict for adverse pathologic features (APFs) or progression-free survival (PFS) in men with intermediate- or high-risk prostate cancer (PCa) undergoing radical prostatectomy (RP). MATERIALS AND METHODS: One hundred nine men with intermediate- (n = 52) or high-risk (n = 57) PCa who underwent RP were retrospectively identified. Logistic regression analysis was performed to evaluate the association of PCA3 score with various APFs (eg, extracapsular extension, seminal vesicle invasion, etc.). Among 78 men with ≥1 year of follow-up, the association between PCA3 score and PFS was assessed using Cox regression analysis. RESULTS: At RP, 52% of patients had at least 1 APF, and with median follow-up of 2.3 years, overall 3-year PFS was 70%. PCA3 was not a significant predictor of any APF on multivariate analysis (MVA), whereas canonical predictors (eg, biopsy Gleason score and initial prostate-specific antigen) remained predictive of various APFs. No significant predictors for PFS were found on MVA, although certain canonical predictors (eg, National Comprehensive Cancer Network risk group) were significant predictors of PFS on univariate analysis (UVA). PCA3 score was not a significant predictor of PFS on either UVA or MVA. CONCLUSION: Unlike in lower risk cohorts, increasing PCA3 score was not associated with any APF in this higher risk cohort, despite enrichment for APFs, nor was it associated with PFS. Notably, multiple known preoperative predictors for APFs were significant on MVA, and multiple predictors were associated with PFS on UVA. Therefore, PCA3 may not be a useful adjunct predictive marker in men with intermediate- or high-risk PCa.

Impact of antioxidants on seminal vesicles function and fertilizing potential in diabetic rats.

Diabetes mellitus significantly affects the male reproduction and sexual function. In the present study, we investigated the diabetes-induced dysfunction of seminal vesicles (SVs) in the diabetes-rat model and the role of antioxidants. Streptozotocin-induced diabetes after 4 weeks caused smaller size of the organs, hypercontractility, histological abnormalities, increased concentrations of malondialdehyde in the serum and tissue, overexpression of oxidative stress markers, and cleaved caspase-3 as identified by immunohistochemistry in the SVs. In addition, diabetes resulted in deceased levels of serum testosterone and no newborns after the mating studies. Antioxidants significantly normalized all the above parameters, except for the severely decreased serum testosterone levels and the negative outcome of the mating studies. The present study gives evidence for the important role of diabetes-induced oxidative stress in the function and structure of these androgen-dependent organs. Antioxidants may be a promising supplementary therapy for diabetic male patients to alleviate ejaculatory disorders but alone is not efficient treatment for the mitigation of infertility.

Role of androgen and estrogen receptors for the action of dehydroepiandrosterone (DHEA).

Dehydroepiandrosterone (DHEA) is an abundant steroid hormone, and its mechanism of action is yet to be determined. The aim of this study was to elucidate the importance of androgen receptors (ARs) and estrogen receptors (ERs) for DHEA function. Orchidectomized C57BL/6 mice were treated with DHEA, DHT, 17ß-estradiol-3-benzoate (E2), or vehicle. Orchidectomized AR-deficient (ARKO) mice and wild-type (WT) littermates were treated with DHEA or vehicle for 2.5 weeks. At termination, bone mineral density (BMD) was evaluated, thymus and seminal vesicles were weighted, and submandibular glands (SMGs) were histologically examined. To evaluate the in vivo ER activation of the classical estrogen signaling pathway, estrogen response element reporter mice were treated with DHEA, DHT, E2, or vehicle, and a reporter gene was investigated in different sex steroid-sensitive organs after 24 hours. DHEA treatment increased trabecular BMD and thymic atrophy in both WT and ARKO mice. In WT mice, DHEA induced enlargement of glands in the SMGs, whereas this effect was absent in ARKO mice. Furthermore, DHEA was able to induce activation of classical estrogen signaling in bone, thymus, and seminal vesicles but not in the SMGs. In summary, the DHEA effects on trabecular BMD and thymus do not require signaling via AR and DHEA can activate the classical estrogen signaling in these organs. In contrast, DHEA induction of gland size in the SMGs is dependent on AR and does not involve classical estrogen signaling. Thus, both ERs and ARs are involved in mediating the effects of DHEA in an organ-dependent manner.

Corrective role of Eugenia jambolana on testicular impairment in streptozotocin-induced diabetic male albino rat: an approach through genomic and proteomic study.

The present study was conducted to explore the effect of ethyl acetate fraction of hydro-methanolic (40 : 60) extract of seed of Eugenia jambolana on testicular impairment in diabetic rats. In this respect, biomarkers of oxidative stress, genomics and proteomics in testicular tissue were assessed. Side by side, glycated haemoglobin, serum testosterone, activities of glutamate oxaloacetate transaminase and glutamate pyruvate transaminase in serum, epididymal sperm count including reproductive organosomatic indices were evaluated. Results indicate that a significant recovery (P < 0.05) in the levels of these parameters in fraction-treated diabetic group in comparison with diabetic control. A significant recovery was noted (P < 0.05) in the expression of Bax and Bcl-2 gene towards the control after the treatment of said fraction. Histological study also focused a significant recovery (P < 0.05) in the number of different generation of germ cells at stage VII of spermatogenesis in fraction-treated diabetic group. The said fraction treatment to diabetic rat can recover the activities of serum glutamate oxaloacetate transaminase and glutamate pyruvate transaminase significantly towards the control (P < 0.05). Finally, it may be concluded that ethyl acetate fraction of seed of E. jambolana has a promiseable remedial effect on diabetes-induced testicular dysfunctions in male rat without inducing any metabolic toxicity.

Selenoprotein P in seminal fluid is a novel biomarker of sperm quality.

Hepatically-derived selenoprotein P (SePP) transports selenium (Se) via blood to other tissues including the testes. Male Sepp-knockout mice are infertile. SePP-mediated Se transport to Sertoli cells is needed for supporting biosynthesis of the selenoenzyme glutathione peroxidase-4 (GPX4) in spermatozoa. GPX4 becomes a structural component of sperm midpiece during sperm maturation, and its expression correlates to semen quality. We tested whether SePP is also present in seminal plasma, potentially correlating to fertility parameters. Semen quality was assessed by sperm density, morphology and motility. SePP was measured by an immunoluminometric assay, and trace elements were determined by X-ray fluorescence spectroscopy. SePP levels were considerably lower in seminal plasma as compared to serum (0.4±0.1 mg/l vs. 3.5±1.0 mg/l); Se concentrations showed a similar but less pronounced difference (48.9±20.7 µg/l vs. 106.7±17.3 µg/l). Se and Zn correlated positively in seminal fluid but not in serum. Seminal plasma SePP concentrations were independent of serum SePP concentrations, but correlated positively to sperm density and fraction of vital sperm. SePP concentrations in seminal plasma of vasectomized men were similar to controls indicating that accessory sex glands are a testes-independent source of SePP. This notion was corroborated by histochemical analyses localizing SePP in epithelial cells of seminal vesicles. We conclude that SePP is not only involved in Se transport to testes supporting GPX4 biosynthesis but it also becomes secreted into seminal plasma, likely important to protect sperm during storage, genital tract passage and final journey.

Differentially expressed androgen-regulated genes in androgen-sensitive tissues reveal potential biomarkers of early prostate cancer.

BACKGROUND: Several data favor androgen receptor implication in prostate cancer initiation through the induction of several gene activation programs. The aim of the study is to identify potential biomarkers for early diagnosis of prostate cancer (PCa) among androgen-regulated genes (ARG) and to evaluate comparative expression of these genes in normal prostate and normal prostate-related androgen-sensitive tissues that do not (or rarely) give rise to cancer. METHODS: ARG were selected in non-neoplastic adult human prostatic epithelial RWPE-1 cells stably expressing an exogenous human androgen receptor, using RNA-microarrays and validation by qRT-PCR. Expression of 48 preselected genes was quantified in tissue samples (seminal vesicles, prostate transitional zones and prostate cancers, benign prostatic hypertrophy obtained from surgical specimens) using TaqMan® low-density arrays. The diagnostic performances of these potential biomarkers were compared to that of genes known to be associated with PCa (i.e. PCA3 and DLX1). RESULTS AND DISCUSSION: By crossing expression studies in 26 matched PCa and normal prostate transitional zone samples, and 35 matched seminal vesicle and PCa samples, 14 genes were identified. Similarly, 9 genes were overexpressed in 15 benign prostatic hypertrophy samples, as compared to PCa samples. Overall, we selected 8 genes of interest to evaluate their diagnostic performances in comparison with that of PCA3 and DLX1. Among them, 3 genes: CRYAB, KCNMA1 and SDPR, were overexpressed in all 3 reference non-cancerous tissues. The areas under ROC curves of these genes reached those of PCA3 (0.91) and DLX1 (0.94). CONCLUSIONS: We identified ARG with reduced expression in PCa and with significant diagnostic values for discriminating between cancerous and non-cancerous prostatic tissues, similar that of PCA3. Given their expression pattern, they could be considered as potentially protective against prostate cancer. Moreover, they could be complementary to known genes overexpressed in PCa and included along with them in multiplex diagnostic tools.

A doxycycline-inducible, tissue-specific aromatase-expressing transgenic mouse.

Aromatase converts androgens to estrogens and it is expressed in gonads and non-reproductive tissues (e.g. brain and adipose tissues). As circulating levels of estrogens in males are low, we hypothesize that local estrogen production is important for the regulation of physiological functions (e.g. metabolism) and pathological development (e.g. breast and prostate cancers) by acting in a paracrine and/or intracrine manner. We generated a tissue-specific doxycycline-inducible, aromatase transgenic mouse to test this hypothesis. The transgene construct (pTetOAROM) consists of a full-length human aromatase cDNA (hAROM) and a luciferase gene under the control of a bi-directional tetracycline-responsive promoter (pTetO), which is regulated by transactivators (rtTA or tTA) and doxycycline. Our in vitro studies using MBA-MB-231tet cells stably expressing rtTA, showed that doxycycline treatment induced transgene expression of hAROM transcripts by 17-fold (P = 0.01), aromatase activity by 26-fold, (P = 0.0008) and luciferase activity by 9.6-fold (P = 0.0006). Pronuclear microinjection of the transgene generated four pTetOAROM founder mice. A male founder was bred with a female mammary gland-specific rtTA mouse (MMTVrtTA) to produce MMTVrtTA-pTetOAROM double-transgenic mice. Upon doxycycline treatment via drinking water, human aromatase expression was detected by RT-PCR, specifically in mammary glands, salivary glands and seminal vesicles of double-stransgenic mice. Luciferase expression and activity was detected in these tissues by in vivo bioluminescence imaging, in vitro luciferase assay and RT-PCR. In summary, we generated a transgenic mouse model that expresses the human aromatase transgene in a temporal- and spatial-specific manner, which will be a useful model to study the physiological importance of local estrogen production.

Exposure of human seminal vesicle tissue to phosphodiesterase (PDE) inhibitors antagonizes the contraction induced by norepinephrine and increases production of cyclic nucleotides.

OBJECTIVES: To investigate further the role of phosphodiesterase (PDE) isoenzymes in the control of human seminal vesicle (SV) smooth muscle contractility, we examined the functional responses of isolated SV tissue to various PDE inhibitors. It has been suggested that the application of inhibitors of the PDE type 5 may facilitate SV smooth muscle relaxation and, subsequently, retard ejaculatory response. METHODS: Using the organ bath technique, strip preparations of human SV were exposed for 5 minutes to 1 µM of the PDE inhibitors milrinone (PDE3 inhibitor), rolipram, Ro 20-1724 (PDE4 inhibitors), and sildenafil (PDE5 inhibitor). Norepinephrine (NE, alpha agonist) was then added (0,1 µM, 1 µM, and 10 µM) and isometric responses were recorded. A contraction-response curve to NE in the absence of PDE inhibitors was also generated. Drug effects on the production of cyclic adenosine monophosphate (AMP) and cyclic guanosine monophosphate (GMP) were measured by means of radioimmunometric assays. RESULTS: The contraction induced by NE was effectively antagonized by 1 µM of rolipram (83.3% inhibition), Ro 20-1724 (72.3% inhibition), sildenafil (41.6% inhibition), and milrinone (37.5% inhibition). The inhibition of force generation was paralleled by a 1.6-fold to 2.8-fold increase in tissue cyclic AMP (induced by milrinone, rolipram, Ro 20-1724), and a 12-fold rise in cyclic GMP (induced by sildenafil). CONCLUSION: The findings demonstrate that PDE inhibitors can counteract the contraction of human SV mediated by alpha-adrenergic receptors and enhance levels of cyclic nucleotides. This might be of importance with regard to the identification of new options for the pharmacological treatment of premature ejaculation.

The effect of green tea on oxidative damage and tumour formation in Lobund-Wistar rats.

A number of epidemiological studies suggest that the consumption of green tea reduces the incidence of prostate cancer. As the major catechins present in green tea are potent antioxidants, we hypothesized that genetic and cellular damage induced by oxygen free radicals could be significantly reduced by potent antioxidants in green tea, thus reducing the cumulative genetic and cellular damage with age, and slowing or preventing tumour formation. Long-term administration of a decaffeinated green tea extract to Lobund-Wistar rats for periods up to 26 months almost halved the incidence of primary tumours in the genitourinary tract when compared with an age-matched cohort receiving just water. We observed no inhibition of DNA adduct formation or lipid peroxidation in animals consuming green tea compared with animals consuming deionized water. The decrease in tumour formation was associated with an increase in 8-hydroxy-2'deoxyguanosine and 4-hydroxynonenal content (markers of DNA adduct formation and lipid peroxidation, respectively) in the epithelium of the ventral prostate in aging animals. In addition, there was an increase in 8-hydroxy-2'deoxyguanosine expression, but no change in 4-hydroxynonenal expression in the seminal vesicles of older animals. An age-associated increase in expression of the antioxidant enzymes manganese superoxide dismutase and catalase in the epithelium of the ventral prostate of aging animals was observed. Furthermore, there was also an increase in manganese superoxide dismutase expression, but no change in catalase expression in the seminal vesicles of older animals. These data demonstrate that consumption of green tea decreases the incidence of genitourinary tract tumours in the Lobund-Wistar rat, but has no effect on age-associated DNA adduct formation and lipid peroxidation in the ventral prostate and seminal vesicles of the aging rat.

Distribution of alpha-, gamma (+beta)- and delta-tocopherol in the seminal plasma, spermatozoa and seminal vesicles of rabbit.

Dietary vitamin E supplementation plays a key role in animal reproduction by protecting germ cells from oxidative damage. Recently, alpha-tocopherol homologues (namely, beta-, gamma- and delta-tocopherol) have been the object of increasing research because of their peculiar nonantioxidant properties. We found that these tocol-derived compounds are not homogeneously distributed among semen components. Alpha-T was the major vitamin E homologue found in all semen fractions. Half of the total gamma (+beta)-T was found in germ cells, while more than 50% of total delta-T was preferentially accumulated in seminal plasma. The concentration of various tocol-derived compounds depended on their relative amounts in diet and the competition for saturable enzymes implicated in their metabolism. A higher concentration of delta-T in seminal plasma may be related to its more polar nature. However, the biological function of this compound in semen remains to be cleared. To our knowledge, this is the first study aimed at identifying alpha-tocopherol homologues in rabbit semen fractions.

Selenium accumulation in prostate tissue during a randomized, controlled short-term trial of l-selenomethionine: a Southwest Oncology Group Study.

PURPOSE: Epidemiologic and clinical data suggest that selenium could prevent prostate cancer, but it has not been shown that supplemental selenium leads to an increased concentration of selenium in prostate tissue compared with adjacent tissue. EXPERIMENTAL DESIGN: We conducted a randomized, controlled, short-term trial of l-selenomethionine (SeMet) versus observation in men with organ-confined prostate cancer. The primary endpoint was the measurement of selenium concentration in prostate tissue and seminal vesicle (SV). We assessed baseline selenium levels in serum and in toenail specimens (reflecting long-term intake) and post-intervention selenium levels in serum, and in prostate and SV tissues using hydride generation atomic fluorescence spectroscopy. RESULTS: Sixty-six eligible patients were randomly assigned to the SeMet (n = 34) or observation (n = 32) arm; both arms had similar baseline patient characteristics. Baseline serum selenium was similar in the two groups (P = 0.64). Baseline toenail selenium levels were slightly higher in the SeMet group than in the control group (P = 0.07). After the intervention, the mean serum selenium level increased 15% in the SeMet arm and was higher than in the observation arm (P = 0.001). The selenium concentration in prostate tissue was 22% higher in the SeMet arm (n = 26) than in the observation arm (n = 25; 1.80 versus 1.47 ppm; P = 0.003, Wilcoxon rank sum test) and remained significantly higher after adjusting for chronic selenium intake (P = 0.021, ANCOVA). SV selenium concentration was similar in both groups (P = 0.384) and was lower than in prostate tissue. CONCLUSIONS: The present study is the first to show that selenium taken as oral supplementation accumulates preferentially in the human prostate gland as opposed to the SV. These findings support the hypothesis that oral selenium supplementation may contribute to the cancer preventive effects of selenium.

Androgen-dependent expression, gene structure, and molecular evolution of guinea pig caltrin II, a WAP-motif protein.

We determined the cDNA and gene structures of guinea pig caltrin II, a unique member of the calcium transporter inhibitors containing a whey acidic protein (WAP) motif, and we established that it is a secretory protein with a potential 21-amino acid signal peptide in its N-terminus. Northern blot analysis and in situ hybridization histochemistry indicated that the expression of caltrin II is restricted to luminal epithelial cells in the seminal vesicles. Its message levels markedly decreased either after castration (and were restored by simultaneous administration of testosterone) or after treatment of the animals with estradiol, suggesting that the expression of caltrin II is androgen-dependent. Recombinant caltrin II had an elastase-inhibitor activity. Comparison of sequence between the caltrin II and related genes and their molecular evolutionary analyses revealed that caltrin II and seminal vesicle secretory proteins (SVPs) appear to be evolved from a common ancestor gene that is made by the fusion of semenogelin and trappin genes. Caltrin II and SVPs lost the transglutaminase substrate domain and the WAP motif, respectively, within a single exon, resulting in the exertion of different functions.

Evaluation of androgenic activity of Zingiber officinale and Pentadiplandra brazzeana in male rats.

AIM: Aqueous extracts of Zingiber officinale and Pentadiplandra brazzeana were tested for their possible androgenic activity in male Wistar rats. METHODS: The aqueous extracts of the two plants were gavaged separately to 2 groups of rats at a similar dose of 600 mg middot kg(-1) middot day(-1) for 8 days. At the end of the treatment, the animals were killed and the blood, testis, epididymis, seminal vesicles and prostate were collected for biochemical analysis. RESULTS: The aqueous extract of Z. officinale significantly increased in the relative weight of the testis, the serum testosterone level, testicular cholesterol level and epididymal a-glucosidase activity. The aqueous extract of P. brazzeana significantly increased the weights of the testis, seminal vesicles and prostate. It also significantly increased the serum and testicular testosterone level. The fructose, alpha-glucosidase and cholesterol levels in P. brazzeana-treated rats were increased by 28 %, 35 % and 114 %, respectively. CONCLUSION: The aqueous extracts of both P. brazzeana and Z. officinale have an androgenic activity, which seems to be more potent with P. brazzeana than with Z. officinale.

Selenium in human male reproductive organs.

The objective of the study was to obtain information on the concentration and distribution of selenium throughout the human male reproductive tract. Material was removed at autopsy from 41 men who had died suddenly and unexpectedly. Semen samples were also provided from 184 men attending an andrology clinic for fertility investigation and from 32 healthy volunteers. Significant positive correlations in the selenium concentration were demonstrated between the different reproductive organs, the testis having the highest concentrations. No correlation was found between the concentration of selenium in the genital organs and liver, kidney or blood, suggesting that its uptake and/or biochemical activity in the reproductive organs may be controlled by similar mechanisms not shared by the other organs. No significant age-dependent changes could be detected in tissue selenium concentrations. In a group of men under fertility investigation, a significant positive correlation was obtained between seminal plasma concentrations of selenium and concentrations of spermatozoa in the same ejaculate. A significant positive correlation between concentrations of zinc and selenium in the same ejaculates indicated that selenium may arise largely from the prostate gland.

Effects of Azadirachta indica leaves on the seminal vesicles and ventral prostate in albino rats.

Oral administration of 20, 40, 60, mg of dry Azadirachta indica leaf powder for 24 days resulted in decrease in the weights of seminal vesicles and ventral prostate, reduction in epithelial height, nuclear diameter and the secretory material in the lumen. Biochemically, there was a decrease in total protein, acid phosphatase activities. Seminal vesicles and ventral prostate being androgen dependent, the regressive changes histologically as well as biochemically, suggests the antiandrogenic property of the neem leaves.

Evaluation of some Samoan and Peruvian medicinal plants by prostaglandin biosynthesis and rat ear oedema assays.

In our ongoing program to find new anti-inflammatory compounds, 58 extracts from 46 different medicinal plant species, used in treatment of inflammatory disorders-38 plants from the traditional medicine of Western Samoa and eight originating from the indigenous medicine of the Shipibo-Conibo tribe of Peruvian Amazonia-ere evaluated. The ability of all extracts to inhibit cyclooxygenase-1 catalysed prostaglandin biosynthesis in vitro was examined. Of the plant species tested 14 showed moderate to strong inhibition; including 11 Samoan and three Peruvian species. Further, 12 Samoan and all eight Peruvian species were investigated on their inhibitory activity of ethyl phenylpropiolate induced rat ear oedema in vivo. Significant activity was shown by 10 of the Samoan and by all eight Peruvian species. An additional evaluation of the most active species was provided through a compilation of existing literature documenting traditional medicinal uses, pharmacological activity and chemical constituents. Several known cyclooxygenase-1 inhibitors were reported to which the observed pharmacological activity can be attributed at least partly. The combination of chemical and pharmacological literature data and our experimental data may help to explain the anti-inflammatory use of these species in indigenous medicine.

A new test for evaluating nonsteroidal anti-inflammatory drugs in vitro: inhibition of prostaglandin E2 production in minced intestinal tissue.

A new method for evaluating the inhibitory effect of nonsteroidal anti-inflammatory drugs on prostaglandin E2 production is presented. Minced rat intestinal tissue was incubated with a nonsteroidal anti-inflammatory drug and homogenized. After centrifugation, prostaglandin E2 in the supernatant was measured by radioimmunoassay. The production of prostaglandin E2 was decreased by nonsteroidal anti-inflammatory drugs, in a concentration-dependent manner, the order of potency being diclofenac greater than loxoprofen greater than indomethacin greater than ibuprofen greater than TA-847 (imidazole derivative). Loxoprofen, a prodrug, inhibited the prostaglandin E2 production. In a classical enzyme assay with sheep seminal vesicle microsomal prostaglandin endoperoxide synthase, the order of inhibitory potency was TA-847 greater than diclofenac greater than indomethacin greater than ibuprofen. The inhibitory effect of loxoprofen was very weak. On the other hand, the potency order of these nonsteroidal anti-inflammatory drugs, with regard to their anti-inflammatory effect as determined in the rat carrageenin-induced paw edema model, was loxoprofen greater than indomethacin greater than diclofenac greater than ibuprofen greater than TA-847. The results of the new method with intestinal tissue showed thus a good correlation with the anti-inflammatory activity in vivo.

Tissue disposition of boron in male Fischer rats.

Boric acid (H3BO3), an inorganic acid with widespread commercial use and consumer exposure, impairs fertility in male rodents at dose levels lower than those required to cause other adverse effects. Previous studies found a testicular lesion in adult Fischer rats fed 9000 ppm boric acid (1575 ppm boron) and slightly reduced basal serum testosterone levels. A CNS-mediated hormonal component to this lesion was suggested. Detailed data on the tissue disposition of boron in the rat, including accessory sex organs and the brain, are lacking. This study examined the tissue disposition of boron in reproductive, accessory sex organs, and other selected tissues in adult male Fischer rats fed 9000 ppm boric acid to determine if selective accumulation of boron in reproductive tissues, accessory sex organs, and/or the brain might correlate with and explain the apparent selective testicular toxicity. Adult male Fischer rats were fed 9000 ppm boric acid for up to 7 days. Animals were killed at 1, 2, 3, 4, and 7 days after the start of exposure. Plasma and excised tissues were heat-digested in acid and analyzed for boron by inductively coupled argon plasma emission spectrometry (ICAP). With the exception of adrenal glands, control boron levels in all tissues examined were below 4 micrograms/g. There was a rapid increase in plasma and tissue boron 1 day after the start of exposure (range 2- to 20-fold), with the exception of adipose tissue. With the exception of bone and adipose tissue, all soft tissues examined, including the testis, epididymis, accessory sex organs, hypothalamus, and rest of brain, appeared to reach steady-state boron levels (range 12-30 micrograms/g) by 3-4 days. Bone boron levels continued to increase up to the termination at 7 days (40-50 micrograms/g by Day 7). Bone attained the greatest concentration of boron (2- to 3-fold over plasma levels) while levels in adipose tissue were 20% of plasma levels during the 7-day exposure period. All other tissues appeared to show no appreciable accumulation of boron over plasma levels. The data suggest that neither the apparent selective testicular toxicity nor the slight CNS hormonal effect associated with boric acid exposure can be explained on the basis of selective accumulation of boron in the testis or brain/hypothalamus, respectively. Thus, the testicular toxicity is likely the result of certain biological processes that are unique to the testis and which are targets of boron exposure.