F1 Female Mice Research Articles

Impact of mothers' experience and early-life stress on aggression and cognition in adult male mice.

The postnatal period is important for brain development and behavioral programming. Here, we hypothesized that females' stressful experience early in life can lead to disruption of mother-offspring interactions with their own progeny. The objective of this study was to assess the effects of mothers' stressful experience, early-life stress, or both on the behavior of adult male mice. In this study, female mice were allowed to raise their pups either without exposure to stress (normal rearing conditions, NC) or with exposure to maternal separation (3hr/day, maternal separation, MS). Adult F1 female mice who had experienced MS (stressed mothers, SM) or had been reared normally (undisturbed mothers, UM) were used for generating F2 offspring, which was then exposed (or not exposed) to early-life stress. We assessed anxiety-like behavior, exploratory activity, locomotor activity, aggression, and cognition in four groups of adult F2 males (UM+NC, UM+MS, SM+NC, and SM+MS). We found that SM+MS males become more aggressive if agonistic contact is long enough; these results point to a change in their social coping strategy. Moreover, these aggressive males tended to show better long-term spatial memory. Overall, our findings suggest that mothers' early-life experience may have important implications for the adult behavior of their offspring.

Altered X-chromosome inactivation in T cells may promote sex-biased autoimmune diseases.

Systemic lupus erythematosus (SLE) is an autoimmune disorder that predominantly affects women and is driven by autoreactive T cell-mediated inflammation. It is known that individuals with multiple X-chromosomes are at increased risk for developing SLE; however, the mechanisms underlying this genetic basis are unclear. Here, we use single cell imaging to determine the epigenetic features of the inactive X (Xi) in developing thymocytes, mature T cell subsets, and T cells from SLE patients and mice. We show that Xist RNA and heterochromatin modifications transiently reappear at the Xi and are missing in mature single positive T cells. Activation of mature T cells restores Xist RNA and heterochromatin marks simultaneously back to the Xi. Notably, X-chromosome inactivation (XCI) maintenance is altered in T cells of SLE patients and late-stage-disease NZB/W F1 female mice, and we show that X-linked genes are abnormally upregulated in SLE patient T cells. SLE T cells also have altered expression of XIST RNA interactome genes, accounting for perturbations of Xi epigenetic features. Thus, abnormal XCI maintenance is a feature of SLE disease, and we propose that Xist RNA localization at the Xi could be an important factor for maintaining dosage compensation of X-linked genes in T cells.

Maternal Supplementation with β-Carotene During Pregnancy Disturbs Lipid Metabolism and Glucose Homoeostasis in F1 Female Mice.

β-Carotene (BC), a substitute for vitamin A, is widely used for its benefits. The present study investigates whether in-utero BC administration can alter lipid and glucose homoeostasis in offspring. Pregnant mice are supplemented with BC (1 mg kg-1 weight) by oral gavage once every 3 days, for a total of six doses. Increased visceral fat may be caused by up-regulated PPARγ (peroxisome proliferator-activated receptor gamma) and RXRα/β (retinoid X receptors) in liver and adipose tissue, and glucose intolerance is observed in F1 adult females prenatally supplemented with BC, while F1 males do not exhibit these symptoms. In females, increased serum leptin, resistin, and IL-6 and reduced adiponectin, caused by visceral obesity, may result in downregulated insulin receptor signaling in muscle and further account for glucose intolerance. Increased pancreatic β-cell mass might compensate for the downregulated insulin gene (ins2). Increased glucagon and α-cell mass, accompanied by upregulated glucagon gene (gcg), might also be risk factors for the development of diabetes. Maternal supplementation with BC disturbs lipid metabolism and induces glucose intolerance in F1 female mice, suggesting that BC supplementation during pregnancy should be used with caution.

Increased susceptibility to mammary carcinogenesis and an opposite trend in endometrium in <i>Trp53</i> heterozygous knockout female mice by backcrossing the BALB/c strain onto the background C3H strain

Patients with dominantly inherited Li-Fraumeni syndrome have a loss-of-function mutation in TP53 and develop diverse mesenchymal and epithelial neoplasms at multiple sites. Trp53+/− female mice with the BALB/c background provide unique characteristics for the study of breast cancer in Li-Fraumeni syndrome; however, we previously found that female C3H-Trp53+/− mice did not spontaneously develop mammary tumors. Therefore, we obtained F1 and N2-N4 female mice by backcrossing the BALB/c strain and examined the incidence of mammary and other tumors in lifetime studies. Malignant lymphomas, osteosarcomas, and uterine adenocarcinomas spontaneously developed in approximately 20% or more of Trp53+/− mice with the C3H background. In contrast, the incidence of uterine adenocarcinomas showed a tendency to decrease, while that of mammary adenocarcinomas gradually increased in mice with the BALB/c strain backcross. Wild-type BALB/c female mice are predisposed to a wide spectrum of neoplasms, including mammary tumors, partly due to genetic factors, whereas uterine tumors are uncommon not only in BALB/c mice but also C3H mice. Thus, genetic factors appear to contribute to a strain-specific predisposition to malignant neoplasms in Trp53+/− mice, and further studies are needed to clarify the detailed mechanisms.

Perinatal exposure to di-ethyl-hexyl phthalate via parenteral route induced polycystic ovarian syndrome-like genetic and pathologic changes in F1 offspring mice

Polycystic ovarian syndrome (PCOS) is the disease of anovulation in women with multifactorial causes. Endocrine-disrupting chemicals such as DEHP (Di-ethyl hexyl phthalate) is thought to play a role in the development of PCOS. The routes of exposure to DEHP including the enteral and parenteral routes, and plastic-containing medical devices are one of the source of high DEHP exposure. We hypothesised perinatal exposure to DEHP via parenteral route induce polycystic ovarian syndrome (PCOS)-like genetic, morphologic, and physical changes in adult mice. Pregnant mice were administered DEHP perinatally via parenteral route. The effects of perinatal DEHP exposure was examined in the F1 mice and the results were compared with those obtained for a control group. Offspring female F1 mice exhibited genetic, pathological, and physical changes in the ovaries, similar to those observed in patients with PCOS, after exposure to DEHP in utero and during lactation. Perinatal DEHP exposure caused some genetic and pathologic changes in mice, mimicking PCOS in human.

Quantitative trait loci that determine plasma insulin levels in $$\hbox {F}_{2}$$ F 2 intercross populations produced from crosses between DDD/Sgn and C57BL/6J inbred mice

When compared to C57BL/6J (B6) mice, DDD/Sgn (DDD) mice has substantially higher plasma insulin levels in both sexes. In this study, we performed quantitative trait loci (QTL) mapping of plasma insulin levels in F2 male mice produced by crosses between DDD and B6 mice. By single-QTL scans, we identified one significant QTL on chromosome 9. When body weight was included as an additive covariate, we identified two significant QTL on chromosomes 9 and 12; the latter coincided with a QTL that was previously identified in F2 female mice produced by the same two strains. The inheritance mode and the direction of the allelic effect of QTL on chromosome 12 were similar in both sexes, but those on chromosome 9 differed between males and females, suggesting that the QTL on chromosome 9 was sex-specific. Based on phenotypic correlations of plasma insulin levels with body weight and plasma levels of total cholesterol, triglyceride and testosterone, we subsequently assessed whether these insulin QTL explain the variation in other metabolic traits by using a point-wise significance threshold of P = 0.05. QTL on chromosome 12 had no significant effect on any trait. In contrast, QTL on chromosome 9 had significant effects on body weight and total cholesterol level. We postulate that Gpr68 and Cyp19a1 are plausible candidate genes for QTL on chromosomes 12 and 9, respectively. These findings provide insight into the genetic mechanisms underlying insulin metabolism.

The Dependence of the Mutagenic Effect on the Dose of X-Ray Irradiation in an In Vivo Experiment on Female (CBA×C57Bl/6)F1 Mice.

We studied the mutagenic effect of X-ray irradiation in doses of 0.5, 1, and 1.5 Gy on female (CBA×C57Bl/6)F1 mice. The mutagenic effect (assessed by the parameter "frequency of bone marrow polychromatophilic erythrocytes with micronuclei") linearly depended on the dose of X-ray irradiation in the range of up to 1 Gy and reached the plateau at 1.5 Gy. The fraction of polychromatophilic erythrocytes was 45, 45, and 46% under control conditions (without exposure) and exposure to the irradiation in the doses of 0.5 and 1 Gy, respectively. Irradiation in a dose of 1.5 Gy induced a slight inhibition of erythropoiesis. These data confirm the hypothesis on possible death of highly aberrant erythrocyte precursors after irradiation in high doses.

Nicotine exposure of male mice produces behavioral impairment in multiple generations of descendants.

Use of tobacco products is injurious to health in men and women. However, tobacco use by pregnant women receives greater scrutiny because it can also compromise the health of future generations. More men smoke cigarettes than women. Yet the impact of nicotine use by men upon their descendants has not been as widely scrutinized. We exposed male C57BL/6 mice to nicotine (200 μg/mL in drinking water) for 12 wk and bred the mice with drug-naïve females to produce the F1 generation. Male and female F1 mice were bred with drug-naïve partners to produce the F2 generation. We analyzed spontaneous locomotor activity, working memory, attention, and reversal learning in male and female F1 and F2 mice. Both male and female F1 mice derived from the nicotine-exposed males showed significant increases in spontaneous locomotor activity and significant deficits in reversal learning. The male F1 mice also showed significant deficits in attention, brain monoamine content, and dopamine receptor mRNA expression. Examination of the F2 generation showed that male F2 mice derived from paternally nicotine-exposed female F1 mice had significant deficits in reversal learning. Analysis of epigenetic changes in the spermatozoa of the nicotine-exposed male founders (F0) showed significant changes in global DNA methylation and DNA methylation at promoter regions of the dopamine D2 receptor gene. Our findings show that nicotine exposure of male mice produces behavioral changes in multiple generations of descendants. Nicotine-induced changes in spermatozoal DNA methylation are a plausible mechanism for the transgenerational transmission of the phenotypes. These findings underscore the need to enlarge the current focus of research and public policy targeting nicotine exposure of pregnant mothers by a more equitable focus on nicotine exposure of the mother and the father.

Selective HDAC6 inhibition decreases early stage of lupus nephritis by down-regulating both innate and adaptive immune responses.

We have demonstrated previously that histone deacetylase (HDAC6) expression is increased in animal models of systemic lupus erythematosus (SLE) and that inhibition of HDAC6 decreased disease. In our current studies, we tested if an orally active selective HDAC6 inhibitor would decrease disease pathogenesis in a lupus mouse model with established early disease. Additionally, we sought to delineate the cellular and molecular mechanism(s) of action of a selective HDAC6 inhibitor in SLE. We treated 20-week-old (early-disease) New Zealand Black (NZB)/White F1 female mice with two different doses of the selective HDAC6 inhibitor (ACY-738) for 5 weeks. As the mice aged, we determined autoantibody production and cytokine levels by enzyme-linked immunosorbent assay (ELISA) and renal function by measuring proteinuria. At the termination of the study, we performed a comprehensive analysis on B cells, T cells and innate immune cells using flow cytometry and examined renal tissue for immune-mediated pathogenesis using immunohistochemistry and immunofluorescence. Our results showed a reduced germinal centre B cell response, decreased T follicular helper cells and diminished interferon (IFN)-γ production from T helper cells in splenic tissue. Additionally, we found the IFN-α-producing ability of plasmacytoid dendritic cells was decreased along with immunoglobulin isotype switching and the generation of pathogenic autoantibodies. Renal tissue showed decreased immunoglobulin deposition and reduced inflammation as judged by glomerular and interstitial inflammation. Taken together, these studies show selective HDAC6 inhibition decreased several parameters of disease pathogenesis in lupus-prone mice. The decrease was due in part to inhibition of B cell development and response.

Environmental perturbation of the circadian clock during pregnancy leads to transgenerational mood disorder-like behaviors in mice

It remains unknown whether chronic circadian disturbance (CCD) during pregnancy can lead to mood disorders in the offspring. Here we show that pregnant mice in the F0 generation that were exposed to CCD stress displayed depression-like behaviors, and produced offspring in the F1 and F2 generations that also exhibited mood-associated behavioral phenotypes despite the lack of direct stressful experiences during their postnatal or adult period. Prenatal CCD stress was correlated with the elevation of plasma corticosterone levels in F1 mice. Furthermore, the diurnal expression profiles of core circadian clock genes were disrupted in the suprachiasmatic nucleus of F1 mice. Proteomics analysis revealed that prenatal CCD stress resulted in distinct changes in protein expression in the hypothalamus of female F1 mice, in particular proteins that were associated with cellular activities, metabolism, development and diseases. Sex-specific differences in melanocortin 4 receptor expression were apparent in the CCD F1 generation. We conclude that maternal exposure to chronic circadian disturbance during pregnancy can lead to sex-specific mood disorders that persist for at least two filial generations. The underlying mechanisms may depend on transgenerational changes in plasma corticosterone levels, circadian pacemaking, and hypothalamic protein expression.

Antenatal antipsychotic exposure induces multigenerational and gender-specific programming of adiposity and glucose tolerance in adult mouse offspring

Second-generation antipsychotics (SGAs) are well known for their metabolic side effects in humans, including obesity and diabetes. These compounds are maintained during pregnancy to prevent the relapse of psychoses, but they readily diffuse across the placenta to the fetus, as documented with the widely-prescribed drug olanzapine (OLZ). However, observational studies have provided conflicting results on the potential impact of SGAs on fetal growth and body weight, and their effects on metabolic regulation in the offspring. For this reason, our study has tested whether antenatal exposure of CD1 mice to OLZ influenced metabolic outcomes in the offspring of the first (F1) and second (F2) generations. In F1 mice, OLZ antenatal treatment caused a decrease in neonatal body weight in both genders, an effect that persisted throughout life only in male animals. Interestingly, F1 female mice also displayed altered glucose homoeostasis. F2 mice, generated by mating normal males with F1 female mice exposed to OLZ during antenatal life, exhibited higher neonatal body weights which persisted only in F2 female animals. This was associated with expansion of fat mass and a concordant pattern of adipose tissue gene expression. Moreover, male and female F2 mice were glucose-intolerant. Thus, our study has demonstrated that antenatal OLZ exposure induces multigenerational and gender-specific programming of glucose tolerance in the offspring mice as adults, and points to the need for careful monitoring of children exposed to SGAs during pregnancy.

S100a9-deficiency accelerates lupus disease and renal failure in male (NZB x NZW)F1 mice

Abstract All (NZB x NZW)F1 (BWF1) female mice develop lupus-like disease, compared to ~30% of male BWF1 mice. Our previous research described an immunosuppressive effect of Gr1hiCD11bhi cells in male BWF1 mice. Specifically, as BWF1 mice age, female Gr1hi cells lost their ability to suppress altogether, while antibody-mediated depletion of Gr1hi cells accelerated disease development in male mice only. Reverse transcriptase-PCR studies revealed upregulated S100a9 and S100a8 mRNA levels in male flow-sorted Gr1hi cells as compared to cells from female BWF1 mice and non-autoimmune stains, leading us to hypothesize that S100a8/a9 produced by male Gr1hi cells is immunosuppressive. To study this, we created S100a9-deficient BWF1 mice. Our results showed spleen weight and splenocyte count, indicators of lupus advancement, were significantly higher in S100a9−/−male mice. Additionally, increased IgG-IC deposition in kidney glomeruli of S100a9−/−male mice was observed along with a significant increase in serum anti-chromatin IgG levels. Deficiency of S100a9 also resulted in increased frequencies of memory B cells and plasma cells in male mice, but not in female mice. Interestingly, S100a9-deficiency caused an accumulation of Gr1hiCD11b+ splenocytes in male mice. We speculated that this is due to a lack of trafficking of Gr1hi cells into the glomerulus of the kidney due to S100a9-deficiency. Subsequent IHC confirmed the lack of S100a9 expression in kidneys from S100a9-deficient mice. Finally, H/E and Trichrome stainings indicated accelerated renal failure in S100a9−/−mice. In conclusion, S100a9 may function as a chemoattractant of Gr1hi cells exerting immunosuppression and protection against lupus-like renal disease in male BWF1 mice.

Selective HDAC6 inhibitor decreases lupus in mice

Abstract Histone deacetylase 6 (HDAC6) is a Class IIb HDACs enzyme primarily residing in the cytoplasm. HDAC6 alters gene transcription by removing acetyl groups from lysine residues on transcription factors. We, and others, have previously demonstrated that HDAC6 expression is increased in systemic lupus erythematosus (SLE) patients and animal models of lupus and that inhibition of HDAC6 decreased disease. In our current studies, we tested if an orally active selective HDAC6 inhibitor would decrease disease pathogenesis in a lupus mouse model with established early disease. Importantly, we sought to delineate the cellular and molecular mechanism(s) of action for the HDAC6 inhibitor. We treated 20-week-old early-diseased NZB/W F1 (lupus) female mice with two different doses of the selective HDAC6 inhibitor (ACY-738) for five weeks. At the termination of the study, our results showed a reduced germinal center B cell response, decreased T follicular helper cells and diminished IFN-g production from T helper cells in splenic tissue. Additionally, we found the IFNa-producing ability of plasmacytoid dendritic cells was decreased along with immunoglobulin isotype switching and the generation of pathogenic autoantibodies. Renal tissue showed decreased immunoglobulin deposition and reduced inflammation as judged by glomerular and interstitial inflammation. Taking together, these studies show selective HDAC inhibition decreased several parameters of disease pathogenesis in lupus prone mice. The decrease was in part due to inhibition of autoreactive B cell differentiation. Studies are currently underway to define further the mechanism of how HDAC6 inhibits auto-reactive B cell differentiation.

Polygenic Control of Carotid Atherosclerosis in a BALB/cJ × SM/J Intercross and a Combined Cross Involving Multiple Mouse Strains.

Atherosclerosis in the carotid arteries is a major cause of ischemic stroke, which accounts for 85% of all stroke cases. Genetic factors contributing to carotid atherosclerosis remain poorly understood. The aim of this study was to identify chromosomal regions harboring genes contributing to carotid atherosclerosis in mice. From an intercross between BALB/cJ (BALB) and SM/J (SM) apolipoprotein E-deficient (Apoe−/−) mice, 228 female F2 mice were generated and fed a “Western” diet for 12 wk. Atherosclerotic lesion sizes in the left carotid artery were quantified. Across the entire genome, 149 genetic markers were genotyped. Quantitative trait locus (QTL) analysis revealed eight loci for carotid lesion sizes, located on chromosomes 1, 5, 12, 13, 15, 16, and 18. Combined cross-linkage analysis using data from this cross, and two previous F2 crosses derived from BALB, C57BL/6J and C3H/HeJ strains, identified five significant QTL on chromosomes 5, 9, 12, and 13, and nine suggestive QTL for carotid atherosclerosis. Of them, the QTL on chromosome 12 had a high LOD score of 9.95. Bioinformatic analysis prioritized Arhgap5, Akap6, Mipol1, Clec14a, Fancm, Nin, Dact1, Rtn1, and Slc38a6 as probable candidate genes for this QTL. Atherosclerotic lesion sizes were significantly correlated with non-HDL cholesterol levels (r = 0.254; p = 0.00016) but inversely correlated with HDL cholesterol levels (r = −0.134; p = 0.049) in the current cross. Thus, we demonstrated the polygenic control of carotid atherosclerosis in mice. The correlations of carotid lesion sizes with non-HDL and HDL suggest that genetic factors exert effects on carotid atherosclerosis partially through modulation of lipoprotein homeostasis.

Prenatal exposure to an environmentally relevant phthalate mixture disrupts reproduction in F1 female mice

Phthalates are used in a large variety of products, such as building materials, medical devices, and personal care products. Most previous studies on the toxicity of phthalates have focused on single phthalates, but it is also important to study the effects of phthalate mixtures because humans are exposed to phthalate mixtures. Thus, we tested the hypothesis that prenatal exposure to an environmentally relevant phthalate mixture adversely affects female reproduction in mice. To test this hypothesis, pregnant CD-1 dams were orally dosed with vehicle (tocopherol-stripped corn oil) or a phthalate mixture (20 and 200μg/kg/day, 200 and 500mg/kg/day) daily from gestational day 10 to birth. The mixture was based on the composition of phthalates detected in urine samples from pregnant women in Illinois. The mixture included 35% diethyl phthalate, 21% di(2-ethylhexyl) phthalate, 15% dibutyl phthalate, 15% diisononyl phthalate, 8% diisobutyl phthalate, and 5% benzylbutyl phthalate. Female mice born to the exposed dams were subjected to tissue collections and fertility tests at different ages. Our results indicate that prenatal exposure to the phthalate mixture significantly increased uterine weight and decreased anogenital distance on postnatal days 8 and 60, induced cystic ovaries at 13months, disrupted estrous cyclicity, reduced fertility-related indices, and caused some breeding complications at 3, 6, and 9months of age. Collectively, our data suggest that prenatal exposure to an environmentally relevant phthalate mixture disrupts aspects of female reproduction in mice.

Increased Transgenerational Intestinal Tumorigenesis in Offspring of Ionizing Radiation Exposed Parent APC1638N/+ Mice

The purpose of the study was to assess transgenerational intestinal tumorigenic effects of low dose ionizing radiation employing a well-characterized mouse model of human colorectal cancer. Mice (6 to 8 weeks old APC1638N/+ mice; n=20 per study group) were exposed to whole-body 25 cGy x-rays and mated 2 days post-irradiation. Intestinal tumorigenesis in male and female F1 mice from No Parents Irradiated (NPI), Both Parents Irradiated (BPI), and Male Parent Irradiated (MPI) groups were compared 210 days after birth. Male and female Direct Parent Irradiated (DPI) groups were additional controls for male and female F1 groups respectively. Data showed higher intestinal tumor frequency (± standard error of the mean) in male and female F1 from BPI (male: 7.81 ± 0.91; female: 5.45 ± 0.36) as well as from MPI (male: 6.30 ± 0.33; female: 4.45 ± 0.33) mice relative to F1 from NPI mice (male: 4.2 ± 0.48; female: 3.35 ± 0.37). Compared to male and female DPI (male: 5.55 ± 0.40; female: 3.60 ± 0.22), tumor frequency in F1 mice of BPI and MPI, though higher, was not statistically significant except for DPI vs. BPI in male mice. Additionally, both BPI and MPI showed increased frequency of larger tumors relative to NPI. In summary, our observations demonstrated that the APC1638N/+ mice due to its low spontaneous tumor frequency could serve as an effective model to study risk of transgenerational carcinogenesis in gastrointestinal tissues after exposure to clinically relevant low doses of ionizing radiation.

Analysis of ovarian gene expression in F2 mouse following perinatal exposure to DEHP via the parenteral route

The aim of this study is analyze the gene expression of the F2 mouse in comparison with the control mouse after exposure of F0 mouse to Di-ethyl hexyl phthalate (DEHP) via the parenteral route during the perinatal period. For this purpose, pregnant F0 mice were injected subcutaneously with corn oil (control group, n=3) or DEHP (treatment group, 30 μg/kg/day, n=3) during pregnancy and lactation. No further treatment was given after weaning of F1 mice. F1 mice were mated and delivered. Six F2 female mice from each group were randomly selected and total RNA was extracted from the ovaries. Microarrays were used to identify the genes and pathways affected by DEHP exposure. As a result, genes related with certain gynecological diseases showed significant changes in expressions. Genes, which were involved in MAPK signaling pathway, p53 signaling pathway, cell cycle, and oocyte maturation, showed significant changes in expression, too.

Granulocyte colony-stimulating factor treatment ameliorates lupus nephritis through the expansion of regulatory T cells.

BackgroundGranulocyte colony-stimulating factor (G-CSF) can induce regulatory T cells (Tregs) as well as myeloid-derived suppressor cells (MDSCs). Despite the immune modulatory effects of G-CSF, results of G-CSF treatment in systemic lupus erythematosus are still controversial. We therefore investigated whether G-CSF can ameliorate lupus nephritis and studied the underlying mechanisms.MethodsNZB/W F1 female mice were treated with G-CSF or phosphate-buffered saline for 5 consecutive days every week from 24 weeks of age, and were analyzed at 36 weeks of age.ResultsG-CSF treatment decreased proteinuria and serum anti-dsDNA, increased serum complement component 3 (C3), and attenuated renal tissue injury including deposition of IgG and C3. G-CSF treatment also decreased serum levels of BUN and creatinine, and ultimately decreased mortality of NZB/W F1 mice. G-CSF treatment induced expansion of CD4+CD25+Foxp3+ Tregs, with decreased renal infiltration of T cells, B cells, inflammatory granulocytes and monocytes in both kidneys and spleen. G-CSF treatment also decreased expression levels of MCP-1, IL-6, IL-2, and IL-10 in renal tissues as well as serum levels of MCP-1, IL-6, TNF-α, IL-10, and IL-17. When Tregs were depleted by PC61 treatment, G-CSF-mediated protective effects on lupus nephritis were abrogated.ConclusionsG-CSF treatment ameliorated lupus nephritis through the preferential expansion of CD4+CD25+Foxp3+ Tregs. Therefore, G-CSF has a therapeutic potential for lupus nephritis.Electronic supplementary materialThe online version of this article (doi:10.1186/s12882-016-0380-x) contains supplementary material, which is available to authorized users.

Genetic analysis of atherosclerosis identifies a major susceptibility locus in the major histocompatibility complex of mice

Background and aimsRecent genome-wide association studies (GWAS) have identified over 50 significant loci containing common variants associated with coronary artery disease. However, these variants explain only 26% of the genetic heritability of the disease, suggesting that many more variants remain to be discovered. Here, we examined the genetic basis underlying the marked difference between SM/J-Apoe−/− and BALB/cJ-Apoe−/− mice in atherosclerotic lesion formation. Methods206 female F2 mice generated from an intercross between the two Apoe−/- strains were fed 12 weeks of western diet. Atherosclerotic lesion sizes in the aortic root were measured and 149 genetic markers genotyped across the entire genome. ResultsA significant locus, named Ath49 (LOD score: 4.18), for atherosclerosis was mapped to the H2 complex [mouse major histocompatibility complex (MHC)] on chromosome 17. Bioinformatic analysis identified 12 probable candidate genes, including Tnfrsf21, Adgrf1, Adgrf5, Mep1a, and Pla2g7. Corresponding human genomic regions of Ath49 showed significant association with coronary heart disease. Five suggestive loci on chromosomes 1, 4, 5, and 8 for atherosclerosis were also identified. Atherosclerotic lesion sizes were significantly correlated with HDL but not with non-HDL cholesterol, triglyceride or glucose levels in the F2 cohort. ConclusionsWe have identified the MHC as a major genetic determinant of atherosclerosis, highlighting the importance of inflammation in atherogenesis.

Inhibition of G Protein βγ Subunit Signaling Abrogates Nephritis in Lupus-Prone Mice.

Despite considerable advances in the understanding of systemic lupus erythematosus (SLE), there is still an urgent need for new and more targeted treatment approaches. We previously demonstrated that small-molecule blockade of G protein βγ subunit (Gβγ) signaling inhibits acute inflammation through inhibition of chemokine receptor signal transduction. We undertook this study to determine whether inhibition of Gβγ signaling ameliorates disease in a mouse model of SLE. Lupus-prone (NZB × NZW)F1 female mice were prophylactically or therapeutically treated with the small-molecule Gβγ inhibitor gallein. Tissue samples were analyzed by flow cytometry and immunohistochemistry. The development and extent of nephritis were assessed by monitoring proteinuria and by immunohistochemical analysis. Serum immunoglobulin levels were measured by enzyme-linked immunosorbent assay, and total IgG and anti-double-stranded DNA (anti-dsDNA) antibody-secreting cells were measured by enzyme-linked immunospot assay. Gallein inhibited accumulation of T cells and germinal center (GC) B cells in the spleen. Both prophylactic and therapeutic treatment reduced GC size, decreased antibody-secreting cell production in the spleen, and markedly decreased accumulation of autoreactive anti-dsDNA antibody-secreting cells in kidneys. Gallein also reduced immune complex deposition in kidneys. Finally, gallein treatment dramatically inhibited kidney inflammation, prevented glomerular damage, and decreased proteinuria. Mechanistically, gallein inhibited immune cell migration and signaling in response to chemokines in vitro, which suggests that its mechanisms of action in vivo are inhibition of migration of immune cells to sites of inflammation and inhibition of immune cell maturation. Overall, these data demonstrate the potential use of gallein or novel inhibitors of Gβγ signaling in SLE treatment.