Hexachlorocyclohexane-Induced Tumorigenicity in Mice under Different Experimental Conditions

1983 ◽  
Vol 69 (5) ◽  
pp. 383-386 ◽  
Author(s):  
Khan Md. Munir ◽  
Chitralekha Sudhakar Soman ◽  
Sumati Vasudeo Bhide
Keyword(s):  
Sex Hormones ◽  
Liver Tumors ◽  
Age Groups ◽  
Tumor Incidence ◽  
Male Mice ◽  
Experimental Conditions ◽  
Continuous Administration ◽  
Female Mice

Continuous administration of 500 ppm hexachlorocyclohexane (HCH) in the diet induced 100 % liver tumors in mice, but none were observed in rats and hamsters treated with the same dose of HCH. In Swiss male mice, tumor incidence at earlier ages was greater than that observed in corresponding age groups of Swiss female mice. It was further observed that in Swiss females, sex hormones retarded the tumorigenic effect of HCH; in BALB/c mice a similar phenomenon was not observed.

scholarly journals MOUSE COMPLEMENT: THE EFFECT OF SEX HORMONES AND CASTRATION ON TWO OF THE LATE-ACTING COMPONENTS

1967 ◽  
Vol 125 (4) ◽  
pp. 657-672 ◽  
Author(s):  
Winthrop H. Churchill ◽  
Ronald M. Weintraub ◽  
Tibor Borsos ◽  
Herbert J. Rapp
Keyword(s):  
Sex Hormones ◽  
Male Mice ◽  
Complement Components ◽  
Female Mice

The titer of late-acting complement components in sera from male mice is 8–10 times higher than the titer of sera from female mice. Using assays developed to measure the serum content of two of the late-acting components, we have shown that this difference is due to the effect of androgen and estrogen on these two late-acting complement components. These two components have been tentatively identified as C'5 and C'6. Androgen and estrogen have greater effect on C'6 than on C'5. The possibility has not been excluded that still other of the late-acting complement components are affected by androgens and estrogens. The course of homograft rejection was unchanged in mice deficient in C'5 and C'6.

scholarly journals Male sex hormones promote vagally mediated reflex airway responsiveness to cholinergic stimulation

2007 ◽  
Vol 292 (4) ◽  
pp. L908-L914 ◽  
Author(s):  
Jeffrey W. Card ◽  
James W. Voltz ◽  
Catherine D. Ferguson ◽  
Michelle A. Carey ◽  
Laura M. DeGraff ◽  
...  
Keyword(s):  
Sex Hormones ◽  
Ex Vivo ◽  
Airway Responsiveness ◽  
Male Mice ◽  
Cholinergic Stimulation ◽  
Intact Female ◽  
Reflex Mechanism ◽  
Female Mice ◽  
Male Sex

A sex disparity in airway responsiveness to cholinergic stimulation has been observed in laboratory mice in that males are considerably more responsive than females, but the basis for this difference is unclear. In this report, we demonstrate that male sex hormones promote murine airway responsiveness to cholinergic stimulation via vagus nerve-mediated reflex mechanisms. In tissue bath preparations, no sex-based differences were observed in the contractile responses of isolated tracheal and bronchial ring segments to carbachol, indicating that the mechanism(s) responsible for the in vivo sex difference is (are) absent ex vivo. Bilateral cervical vagotomy was found to abolish in vivo airway responsiveness to methacholine in male mice, whereas it did not alter the responses of females, suggesting a regulatory role for male sex hormones in promoting reflex airway constriction. To test this possibility, we next studied mice with altered circulating male sex hormone levels. Castrated male mice displayed airway responsiveness equivalent to that observed in intact females, whereas administration of exogenous testosterone to castrated males restored responsiveness, albeit not to the level observed in intact males. Administration of exogenous testosterone to intact female mice similarly enhanced responsiveness. Importantly, the promotive effects of exogenous testosterone in castrated male and intact female mice were absent when bilateral vagotomy was performed. Together, these data indicate that male sex hormones promote cholinergic airway responsiveness via a vagally mediated reflex mechanism that may be important in the regulation of airway tone in the normal and diseased lung.

scholarly journals Bridging Sex-Specific Differences in the CAR-Mediated Hepatocarcinogenesis of Nitrapyrin Using Molecular and Apical Endpoints

2021 ◽  
Vol 3 ◽  
Author(s):  
Lynea Murphy ◽  
Matthew J. LeBaron ◽  
Kamin Johnson ◽  
Reza J. Rasoulpour ◽  
Xiujuan Wang ◽  
...  
Keyword(s):  
Mode Of Action ◽  
Liver Tumors ◽  
Constitutive Androstane Receptor ◽  
Nitrification Inhibitor ◽  
Tumor Formation ◽  
Male Mice ◽  
Female Mice ◽  
Increased Sensitivity ◽  
Males And Females ◽  
Related Increase

Nitrapyrin, a nitrification inhibitor, produces liver tumors in B6C3F1 mice. In a 2-year oncogenicity study, increased incidence of mice with hepatocellular tumors was observed following exposure to 125 (females only) or 250 mg/kg/day (males and females) nitrapyrin in the diet. Previous data was generated in male mice to support a mode-of-action (MoA) characterized by constitutive androstane receptor (CAR) nuclear receptor (NR) activation, increased hepatocellular proliferation, and subsequent hepatocellular foci and tumor formation. Uncertainty as to the relevance of this MoA for females remained given the increased sensitivity to tumor formation in female mice. A targeted MoA study was conducted to evaluate CAR activation and hepatic responses in female mice treated with the female carcinogenic dose of nitrapyrin for 4 days. Nitrapyrin induced a treatment-related increase in hepatocellular hypertrophy and hepatocellular proliferation. Nitrapyrin also induced a dose-related increase in the Cyp2b10/CAR-associated transcript and liver weights. Nitrapyrin-induced liver weights and Cyp2b10 gene expression for both males and females were compared to data generated from three other established CAR activators; methyl isobutyl ketone, phenobarbital, and sulfoxaflor. The response observed in female mice following exposure to nitrapyrin was within range of the degree of change observed in mice following exposure to tumorigenic doses of other CAR activators. Consistent with the liver MoA in male mice, these data support a CAR-mediated mode of action for nitrapyrin-induced liver tumors in female mice, with the understanding that a focused approach minimizing animal use can bridge male and female datasets when sex-specific carcinogenic differences are observed.

EFFECT OF SEX HORMONES ON EHRLICH MOUSE ASCITES CANCER

1960 ◽  
Vol XXXIV (III) ◽  
pp. 437-448
Author(s):  
C. G. Ahlström ◽  
N. Jonsson
Keyword(s):  
Cancer Cells ◽  
Sex Hormones ◽  
Previous Investigation ◽  
Early Growth ◽  
Male Mice ◽  
Female Mice ◽  
Small Doses ◽  
Mouse Ascites ◽  
Males And Females ◽  
The Difference

ABSTRACT Ehrlich mouse ascites cancer grew better during the first 3 days after inoculation in female than in male mice. The difference was only demonstrable on inoculation with small doses of cancer cells and could not be seen when large doses were used. On the 5th day after inoculation no difference could be observed in the growth of the cancer between males and females. Gonadectomy had no influence on the growth of the cancer. Testosterone inhibited the growth of the cancer in castrated male mice. It had no effect on the growth of the cancer in castrated female mice. Oestradiol did not influence the growth of the cancer in castrated male or female mice. It is noteworthy that the results obtained in a previous investigation on the growth of the Ehrlich mouse ascites cancer in hamsters revealed a hormonal influence which was only discernible in its natural host during the early growth of the cancer and then only after transplantation of a relatively small number of cancer cells.

scholarly journals Differences in acidosis-stimulated renal ammonia metabolism in the male and female kidney

2019 ◽  
Vol 317 (4) ◽  
pp. F890-F905 ◽  
Author(s):  
Autumn N. Harris ◽  
Hyun-Wook Lee ◽  
Lijuan Fang ◽  
Jill W. Verlander ◽  
I. David Weiner
Keyword(s):  
Phosphoenolpyruvate Carboxykinase ◽  
Collecting Duct ◽  
Ammonia Excretion ◽  
Volume Density ◽  
Male Mice ◽  
Ammonia Metabolism ◽  
Female Mice ◽  
Predominant Component ◽  
Acid Load ◽  
Acid Loading

Renal ammonia excretion is a critical component of acid-base homeostasis, and changes in ammonia excretion are the predominant component of increased net acid excretion in response to metabolic acidosis. We recently reported substantial sex-dependent differences in basal ammonia metabolism that correlate with sex-dependent differences in renal structure and expression of key proteins involved in ammonia metabolism. The purpose of the present study was to investigate the effect of sex on the renal ammonia response to an exogenous acid load. We studied 4-mo-old C57BL/6 mice. Ammonia excretion, which was less in male mice under basal conditions, increased in response to acid loading to a greater extent in male mice, such that maximal ammonia excretion did not differ between the sexes. Fundamental structural sex differences in the nonacid-loaded kidney persisted after acid loading, with less cortical proximal tubule volume density in the female kidney than in the male kidney, whereas collecting duct volume density was greater in the female kidney. To further investigate sex-dependent differences in the response to acid loading, we examined the expression of proteins involved in ammonia metabolism. The change in expression of phosphoenolpyruvate carboxykinase and Rh family B glycoprotein with acid loading was greater in male mice than in female mice, whereas Na+-K+-2Cl– cotransporter and inner stripe of the outer medulla intercalated cell Rh family C glycoprotein expression were significantly greater in female mice than in male mice. There was no significant sex difference in glutamine synthetase, Na+/H+ exchanger isoform 3, or electrogenic Na+-bicarbonate cotransporter 1 variant A protein expression in response to acid loading. We conclude that substantial sex-dependent differences in the renal ammonia response to acid loading enable a similar maximum ammonia excretion response.

THE EFFECTS OF SPECIES, STRAIN AND SEX IN THYMOLYTIC TESTS OF BETAMETHASONE, DEXAMETHASONE AND OTHER STEROIDS

1962 ◽  
Vol 25 (1) ◽  
pp. 77-85 ◽  
Author(s):  
R. M. ATKINSON ◽  
M. A. PRATT ◽  
E. G. TOMICH
Keyword(s):  
Route Of Administration ◽  
Relative Potency ◽  
Male Mice ◽  
Female Mice ◽  
Betamethasone And Dexamethasone

SUMMARY Cortisol, prednisolone phosphate and the free alcohols and 21-phosphates of betamethasone and dexamethasone have been compared for thymolytic activity by the oral and subcutaneous routes in both sexes of two strains of rats and two strains of mice. The relative potency of betamethasone and dexamethasone differed with the route of administration and the sex, strain and species of animal employed. In female mice of the A2G strain, betamethasone was as potent as dexamethasone; in male mice of this strain, and in both sexes of GFF mice, WAG rats and PVG rats, betamethasone was much less potent than dexamethasone.

P–060 Dose- dependent mitigation of lead acetate toxicity in males on embryo development in female mice

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
P Dolati ◽  
M J Zamiri ◽  
A Akhlaghi ◽  
Z Jahromi
Keyword(s):  
Adverse Effects ◽  
Embryonic Development ◽  
Embryo Development ◽  
Lead Acetate ◽  
Endocrine System ◽  
Cell Number ◽  
The Other ◽  
Control Group ◽  
Male Mice ◽  
Female Mice

Abstract Study question Does quercetin (75 or 100 mg/kg BW/day) co-administration with lead acetate to male mice affects embryonic development in female mice? Summary answer The low-dose quercetin (75 mg/kg BW/day) ameliorated the adverse effects of lead acetate on mouse embryogenesis. What is known already Lead causes male infertility by impacting on endocrine system and spermatogenesis, and may exert undesirable effects on the offspring. The currently approved treatment for lead poisoning is the use of chelating agents, which form an insoluble complex with lead and shield it from biological targets; thus, reducing its toxicity. One of the main mechanisms of lead-induced toxicity is oxidative stress, and it has been reported that natural antioxidants can reduce the heavy metals toxicity. The aim of the present study was to examine the protective effects of quercetin on the toxicity induced by lead acetate on the embryogenesis in mice. Study design, size, duration Sexually mature (eight-week-old) NMRI male mice (n = 24) were randomly divided into four groups (n = 6 per group) receiving (i) distilled water (control group); (ii) lead acetate (150 mg/kg BW/day) dissolved in deionized water (LA); (iii) lead acetate (150 mg/kg BW/day) + quercetin (75 mg/kg BW/day) (LQ75); (IV) lead acetate (150 mg/kg BW/day) + quercetin (100 mg/kg BW/day) (LQ100). Treatments were applied daily as oral gavages for one cycle of the seminiferous epithelium (35 days). Participants/materials, setting, methods At the end of treatment administration, the males were joined with super-ovulated females, and the retrieved zygotes were cultured for evaluation of the embryo development (at 2-cell, 4-cell, 8-cell, and blastocyst stages), and blastocyst cell number using differential staining (propidium iodide and bisbenzimide). After incubation of capacitated sperm with oocytes, an ultraviolet light microscope was used following 3 min incubation with 25 µg⁄mL bisbenzamide solution for fertilization assessment. Main results and the role of chance Lead acetate (LA) treatment of male mice decreased the 2-cell stage compared with the control group (P > 0.05). There was no difference between control and LQ75, and between LA and LQ100. The other stages of embryonic development were not significantly affected by the treatment. Overall, early embryonic development in the control and LQ75 mice were better than LQ100 and LA mice. The number of cells in the trophectoderm and inner-cell mass were not affected by treatments. However, the total blastocyst cell number in the control was higher than in the other groups; there was no significant difference between LQ100, LQ75 and LA groups. Fertilization rate was not affected by the treatments (P < 0.05). Quercetin acts as a potent antioxidant at low doses, but at high doses exerts a pro-oxidant action. According to previous reports, higher concentrations of quercetin increased apoptosis and necrosis while decreasing the activities of the antioxidant enzymes. Also, it has been suggested that quercetin might disrupt the endocrine system and interfere with Sertoli cell function and sperm motility. Limitations, reasons for caution A limitation of this study is narrow dose selection; more studies are needed to determine the effective dose of quercetin in ameliorating the lead toxicity. There are also side effects of lead-quercetin chelates such as metal redistribution, essential metal loss, accumulation and persistency in intracellular sites, and peroxidation. Wider implications of the findings: Lead administration adversely impacted on the embryogenesis; on the other hand, paternal quercetin co-administration somewhat ameliorated the adverse effects of lead on mice embryogenesis. Trial registration number Not applicable

scholarly journals NPY Deficiency Prevents Postmenopausal Adiposity by Augmenting Estradiol-Mediated Browning

2018 ◽  
Vol 75 (6) ◽  
pp. 1042-1049
Author(s):  
Seongjoon Park ◽  
Erkhembayar Nayantai ◽  
Toshimitsu Komatsu ◽  
Hiroko Hayashi ◽  
Ryoichi Mori ◽  
...  
Keyword(s):  
Body Weight ◽  
Adipose Tissue ◽  
Fat Metabolism ◽  
Male Mice ◽  
Wild Type ◽  
Male And Female ◽  
Female Mice ◽  
Age Related ◽  
Promising Target ◽  
Intracellular Mechanism

Abstract The orexigenic hormone neuropeptide Y (NPY) plays a pivotal role in the peripheral regulation of fat metabolism. However, the mechanisms underlying the effects of sex on NPY function have not been extensively analyzed. In this study, we examined the effects of NPY deficiency on fat metabolism in male and female mice. Body weight was slightly decreased, whereas white adipose tissue (WAT) mass was significantly decreased as the thermogenic program was upregulated in NPY-/- female mice compared with that in wild-type mice; these factors were not altered in response to NPY deficiency in male mice. Moreover, lack of NPY resulted in an increase in luteinizing hormone (LH) expression in the pituitary gland, with concomitant activation of the estradiol-mediated thermogenic program in inguinal WAT, and alleviated age-related modification of adiposity in female mice. Taken together, these data revealed a novel intracellular mechanism of NPY in the regulation of fat metabolism and highlighted the sexual dimorphism of NPY as a promising target for drug development to reduce postmenopausal adiposity.

scholarly journals Gender differences in the response of CD-1 mouse bone to parathyroid hormone: potential role of IGF-I

2006 ◽  
Vol 189 (2) ◽  
pp. 279-287 ◽  
Author(s):  
Yongmei Wang ◽  
Takeshi Sakata ◽  
Hashem Z Elalieh ◽  
Scott J Munson ◽  
Andrew Burghardt ◽  
...  
Keyword(s):  
Gender Differences ◽  
Parathyroid Hormone ◽  
Cortical Bone ◽  
Mineral Apposition Rate ◽  
Mrna Levels ◽  
Male Mice ◽  
Bone Formation Rate ◽  
Male And Female ◽  
Female Mice ◽  
Igf I

Parathyroid hormone (PTH) exerts both catabolic and anabolic actions on bone. Studies on the skeletal effects of PTH have seldom considered the effects of gender. Our study was designed to determine whether the response of mouse bone to PTH differed according to sex. As a first step, we analyzed gender differences with respect to bone mass and structural properties of 4 month old PTH treated (80 μg/kg per day for 2 weeks) male and female CD-1 mice. PTH significantly increased fat free weight/body weight, periosteal bone formation rate, mineral apposition rate, and endosteal single labeling surface, while significantly decreasing medullary area in male mice compared with vehicle treated controls, but induced no significant changes in female mice. We then analyzed the gender differences in bone marrow stromal cells (BMSC) isolated from 4 month old male and female CD-1 mice following treatment with PTH (80 μg/kg per day for 2 weeks). PTH significantly increased the osteogenic colony number and the alkaline phosphatase (ALP) activity (ALP/cell) by day 14 in cultures of BMSCs from male and female mice. PTH also increased the mRNA level of receptor activator of nuclear factor κB ligand in the bone tissue (marrow removed) of both females and males. However, PTH increased the mRNA levels of IGF-I and IGF-IR only in the bones of male mice. Our results indicate that on balance a 2-weeks course of PTH is anabolic on cortical bone in this mouse strain. These effects are more evident in the male mouse. These differences between male and female mice may reflect the greater response to PTH of IGF-I and IGF-IR gene expression in males enhancing the anabolic effect on cortical bone.

scholarly journals Early Exposure to Gut Microbiome Reduces Hepatocellular Carcinoma Risks in Mice

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Yang-Ming Lee ◽  
Wei-Chun Chang ◽  
Fu-Ju Lei ◽  
Chew-Teng Kor ◽  
Hsueh-Chou Lai ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Gut Microbiota ◽  
Gut Microbiome ◽  
Liver Tumors ◽  
Male Mice ◽  
Germ Free ◽  
Housing Environment ◽  
Male Sex ◽  
Group 10 ◽  
Group 5

Aims. Liver cancer is a multietiological disease that has multiple factors contributing to the hepatocarcinogenic process, e.g., hepatitis viruses, carcinogens, male sex, or metabolic factors. Notably, emerging evidence reported that gut microbiota is crucial to the pathogenesis of hepatocellular carcinoma (HCC) via activation of innate immunity. However, the effect of time to gut microbiota exposure after birth is unknown. Using a germ-free animal housing environment, instead of antibiotics, we examined the effects of various time-to-exposure (TTE) to gut microbiota durations on HCC risk. Methods. HBV or carcinogen-mediated spontaneous HCC models were implemented in this study. The HCC incidence rates in mice either kept germ-free (GF; that is, with no exposure to gut microbiota) or exposed to gut microbiota after being moved to a specific pathogen-free (SPF) housing environment and with various time-to-exposure (TTE) durations, namely, 5 weeks after birth, 10 weeks after birth, or since conception (that is, 5-week TTE group, 10-week TTE group, and SPF group, respectively), were recorded. The mice were sacrificed at 30 or 40 weeks after birth, and macro-/microscopic observations and pathological diagnosis were performed. Results. The incidence of liver tumors among the male mice was higher than that among the female mice in the carcinogen-induced HCC mice sacrificed at 40 weeks after birth (with P=0.011, 0.035, 0.0003, and 0.012, respectively, in the GF group, 5-week TTE group, 10-week TTE group, and SPF group). Similarly, in the HBV-HCC model, the incidence of liver tumors among the male mice was significantly higher than that among the female mice (with P=0.013, 0.020, 0.012, and 0.002, respectively, in the GF group, 5-week TTE group, 10-week TTE group, and SPF group). These results suggest that gut microbiota exposure is irrelevant to the male sex preference of HCC. Surprisingly, when comparing carcinogen-induced HCC male mice in the 10-week TTE group (90%; n=10), 5-week TTE group (56%; n=9), and SPF group (30%; n=10) (P=0.020), we found that the incidence of liver tumors was higher in the mice with later exposure to gut microbiome. Similarly, when comparing HBV-HCC male mice in the 10-week TTE group (100%; n=11), 5-week TTE group (70%; n=10), and SPF group (33%; n=9) (P=0.080), we also found that the incidence of liver tumors was higher in the mice with later exposure to gut microbiome. Conclusions. Early (prepubertal) exposure to gut microbiome reduces the risk of HCC development, indicating a potentially important factor for cancer surveillance. Exploring the mechanisms by which such exposure affects HCC risk might lead to novel cancer vaccines.

Sign in / Sign up

Export Citation Format

Share Document