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1.
Methylglyoxal (MG) is a metabolite derived from glycolysis whose levels in the blood and tissues of patients with diabetes are higher than those of healthy individuals, suggesting that MG is associated with the development of diabetic complications. However, it remains unknown whether high levels of MG are a cause or consequence of diabetes. Here, we show that MG negatively affects the expression of uncoupling protein 1 (UCP1), which is involved in thermogenesis and the regulation of systemic metabolism. Decreased Ucp1 expression is associated with obesity and type 2 diabetes. We found that MG attenuated the increase in Ucp1 expression following treatment with isoproterenol in beige adipocytes. However, MG did not affect protein kinase A signaling, the core coordinator of isoproterenol-induced Ucp1 expression. Instead, MG activated c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinases. We found that JNK inhibition, but not p38, recovered isoproterenol-stimulated Ucp1 expression under MG treatment. Altogether, these results suggest an inhibitory role of MG on the thermogenic function of beige adipocytes through the JNK signaling pathway.  相似文献   

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Tissue resident mononuclear phagocytes (Mophs), comprising monocytes, macrophages, and dendritic cells (DCs), play important roles under physiological and pathological conditions. The presence of these cells in the kidney has been known for decades, and studies of renal Mophs (rMophs) are currently underway. Since no unified procedure has been identified to isolate rMophs, results of flow cytometric analysis of rMophs have been inconsistent among studies. We therefore first evaluated a preparative method for rMophs using collagenous digestion. The yield of rMophs greatly increased after the collagenase digestion. In particular, F4/80high rMophs, which were positive for CD11c, a specific marker of DCs, dramatically increased. In addition, since neutrophils are sometimes mixed among rMophs in the analysis of flow cytometry, we established a gating strategy for eliminating neutrophils. To determine the contribution of rMophs to the development of autoimmune nephritis, we analyzed an experimental model of autoimmune nephritis that was applied to Shp1 conditional knockout mice (Shp1 CKO). This knockout strain is generated by crossing a mouse line carrying floxed Shp1 allele to mice expressing Cre recombinase under the control of the CD11c promoter. Shp1 CKO therefore specifically lack Shp1 in cells expressing CD11c. As a result, Shp1 CKO were susceptible to that experimental glomerulonephritis and F4/80high rMophs of Shp1 CKO increased dramatically. In conclusion, our preparative methods for collagenase digestion and gating strategy for neutrophils are necessary for the analysis of rMophs, and Shp1 suppresses the development of autoimmune nephritis through the control of rMophs.  相似文献   

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Waterfowls, such as ducks, are natural hosts of avian influenza virus (AIV) and can genetically limit the pathogenicity. On the other hand, some AIV strains cause severe pathogenicity in chickens. It is suggested that differences in the pathogenicity of AIV infection between waterfowls and chickens are related to the expression of retinoic acid-inducible gene I (RIG-I), a pattern recognition receptor that chickens evolutionally lack. Here, we knocked-in the duck RIG-I bearing the T2A peptide sequence at the 3′ region of the Mx, an interferon-stimulated gene (ISG), in chicken embryo fibroblast cells (DF-1) using the precise integration into target chromosome (PITCh) system to control the duck RIG-I expression in chickens. The expression patterns of the duck RIG-I were then analyzed using qPCR. The knocked-in DF-1 cells expressed RIG-I via the stimulation of IFN-β and poly(I:C) in a dose-dependent manner. Moreover, poly(I:C) stimulation in the knocked-in DF-1 cells upregulated RIG-I-like receptor (RLR) family signaling pathway-related genes IFN-β, OASL, and IRF7. The IFN-β-dependent expression of RIG-I and upregulation of IFN-β in the poly(I:C) stimulation demonstrated a positive-feedback loop via RIG-I, usually evident in ducks. Overall, this novel strategy established RIG-I-dependent immune response in chickens without overexpression of RIG-I and disruption of the host genes.  相似文献   

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The inflammatory hypothesis is one of the most important mechanisms of depression. Fucoidan is a bioactive sulfated polysaccharide abundant in brown seaweeds with anti-inflammatory activity. However, the antidepressant effects of fucoidan on chronic stress-induced depressive-like behaviors have not been well elucidated. Here, we used two different depressive-like mouse models, lipopolysaccharide (LPS) and chronic restraint stress (CRS) models, to explore the detailed molecular mechanism underlying its antidepressant-like effects in C57BL/6J mice by combining multiple behavioral, molecular and immunofluorescence experiments. Adenovirus-mediated overexpression of caspase-1 and pharmacological inhibitors were also used to clarify the antidepressant mechanisms of fucoidan. We found that acute administration of fucoidan did not produce antidepressant effects in the tail suspension test (TST) and forced swim test (FST). Interestingly, chronic fucoidan administration not only dose-dependently reduced stress-induced depressive-like behaviors in the TST, FST, sucrose preference test (SPT), and novelty-suppressed feeding test (NSFT), but also alleviated the downregulation of brain-derived neurotrophic factor (BDNF)-dependent synaptic plasticity via inhibiting caspase-1-mediated inflammation in the hippocampus of mice. Moreover, fucoidan significantly ameliorated behavioral and synaptic plasticity abnormalities in the overexpression of caspase-1 in the hippocampus of mice. Furthermore, blocking BDNF abolished the antidepressant-like effects of fucoidan in mice. Therefore, our findings clearly indicate that fucoidan provides a potential supplementary noninvasive treatment for depression by inhibition of hippocampal inflammation.  相似文献   

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Phosphatidic acid is a key signaling molecule heavily implicated in exocytosis due to its protein-binding partners and propensity to induce negative membrane curvature. One phosphatidic acid-producing enzyme, phospholipase D (PLD), has also been implicated in neurotransmission. Unfortunately, due to the unreliability of reagents, there has been confusion in the literature regarding the expression of PLD isoforms in the mammalian brain which has hampered our understanding of their functional roles in neurons. To address this, we generated epitope-tagged PLD1 and PLD2 knockin mice using CRISPR/Cas9. Using these mice, we show that PLD1 and PLD2 are both localized at synapses by adulthood, with PLD2 expression being considerably higher in glial cells and PLD1 expression predominating in neurons. Interestingly, we observed that only PLD1 is expressed in the mouse retina, where it is found in the synaptic plexiform layers. These data provide critical information regarding the localization and potential role of PLDs in the central nervous system.  相似文献   

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This study was conducted to examine the effects of dietary taurine supplementation on productive performance, nutrient digestibility, antioxidant status, and the gene expression of ileal nutrient transporters in laying quails reared under heat stress (HS). One hundred and eighty laying Japanese quails (Coturnix coturnix japonica) were fed a basal diet or basal diet supplemented with either 2.5 or 5 g of taurine per kg of diet, and reared at either 22 ± 2 °C for 24 h/d (thermoneutral, TN) or 34 ± 2 °C for 8 h/d (HS) for 12 weeks. The quails reared under HS consumed less feed, produced less egg, and had lower dry matter, organic matter and crude protein apparent digestibilities compared with the quails reared under the TN condition (P = 0.001). However, increasing taurine concentrations in the diet improved feed intake and egg production (P = 0.001), but also the apparent digestibilities (P ≤ 0.027) in quails reared under HS. The greater doses (5 g/kg) of taurine resulted in more responses. The quails reared under HS had greater serum and liver MDA concentrations (P = 0.0001) which decreased with dietary taurine supplementations, particularly greater doses. The gene expressions of ileal PEPT1, EAAT3, CAT1, CAT2, SGLT1, SGLT5, GLUT2, and GLUT5 decreased under HS conditions (P = 0.001). However, supplementing taurine, in a dose-dependent fashion, to the diet of quails reared under HS resulted in increases in the gene expressions of the transporters (P < 0.05) except for CAT1. The results of the present work showed that taurine supplementation, particularly with greater doses (5 g/kg), to the diet of laying quails kept under HS acts as alleviating negative effects of HS, resulting in improvements in productive performance and nutrient digestion, and also upregulation of ileal nutrient transporters.  相似文献   

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Alcoholic-related liver disease (ALD) is one of the leading causes of chronic liver disease and morbidity. Unfortunately, the pathogenesis of ALD is still incompletely understood. StARD1 has emerged as a key player in other etiologies of chronic liver disease, and alcohol-induced liver injury exhibits zonal distribution. Here, we report that StARD1 is predominantly expressed in perivenous (PV) zone of liver sections from mice-fed chronic and acute-on-chronic ALD models compared to periportal (PP) area and is observed as early as 10 days of alcohol feeding. Ethanol and chemical hypoxia induced the expression of StARD1 in isolated primary mouse hepatocytes. The zonal-dependent expression of StARD1 resulted in the accumulation of cholesterol in mitochondria and increased lipid peroxidation in PV hepatocytes compared to PP hepatocytes, effects that were abrogated in PV hepatocytes upon hepatocyte-specific Stard1 KO mice. Transmission electron microscopy indicated differential glycogen and lipid droplets content between PP and PV areas, and alcohol feeding decreased glycogen content in both areas while increased lipid droplets content preferentially in PV zone. Moreover, transmission electron microscopy revealed that mitochondria from PV zone exhibited reduced length with respect to PP area, and alcohol feeding increased mitochondrial number, particularly, in PV zone. Extracellular flux analysis indicated lower maximal respiration and spared respiratory capacity in control PV hepatocytes that were reversed upon alcohol feeding. These findings reveal a differential morphology and functional activity of mitochondria between PP and PV hepatocytes following alcohol feeding and that StARD1 may play a key role in the zonal-dependent liver injury characteristic of ALD.  相似文献   

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The thermosensation mechanism plays critical roles in various animals living in different thermal environment. We focused on an axolotl, which is a tailed amphibian originally from Lake Xochimilco area in the Vally of Mexico, and examined its behavior response to heat stimulation. Mild heat at 33 °C induced noxious locomotive activity to axolotls, but the noxious response of another tailed amphibian, Iberian ribbed newt, was not observed at 33 °C. To explore the mechanism for the temperature sensitivity of axolotls, we isolated a cDNA of TRPV1. Using the degenerate primer PCR method, we identified the DNA fragment encoding axolotl TRPV1 (axTRPV1), and then cloned a full-length cDNA. We studied the chemical and thermal sensitivities of axTRPV1 by two-electrode voltage clamp method using Xenopus oocyte expression system. Capsaicin, acid, and 2-aminoethoxydiphenylborane apparently activated axTRPV1 channels in a dose-dependent manner. The analysis of thermal sensitivity showed that axTRPV1 was significantly activated by heat but not by cold. The average temperature threshold for heat-activation was 30.95 ± 0.12 °C. This thermal activation threshold of axTRPV1 is unique and significantly low, when compared with the known thresholds of TRPV1s from various animals. Further, this threshold of axTRPV1 is well consistent with the observation of heat-induced behavior of axolotls at 33 °C, demonstrating that axolotl shows noxious response to mild heat mediated through axTRPV1.  相似文献   

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Introduction& Objectives: Redox signaling is a critical regulator in the process of wound healing. This signaling pathway can be effective in the development or healing of diabetic ulcers through the ECM.In this study, the structure of extracellular matrix investigated in relation to redox signaling in the tissue of patients with diabetic ulcers that lead to organ amputation.Materials and methodsThe case-control design on diabetic patients ulcers as case group and non-diabetic limb ischemia as control were used.Hematoxylin-eosin, trichrome, and elastin staining methods were used for pathological evaluations of ECM. MDA, total thiol, and SOD levels were measured using ELISA kits to assess the oxidative stress level. Also, NO level was measured by using ELISA kits in both groups. Expression levels of genes MMP2, MMP9, and HIF were detected using real-time PCR with SYBR-green assay.ResultsThe pathological results showed an increase in the thickness of collagen and elastin fibers. Lipids atrophy was visible in the tissue isolated from the diabetic wound group. The amount of MAD to evaluate the level of lipid oxidation in patients with diabetic Ulcer was significantly higher than the control group(p < 0.01). Thiol level was significantly lower in the diabetic ulcer group than in the control group(p < 0.0001). The expression of metalloproteinases 2 and 9 genes in the tissues isolated from diabetic ulcers was lower than the control group(p < 0.0001). While the expression of the HIF gene in this group was higher than the control group(p < 0.0001).ConclutionIn the diabetic wound, the HIF secretion due to hypoxic conditions is beneficial for matrix deposition and prevents protease activity, but if the hypoxia persists, it can lead to ECM deposition subsequently increases the tissue pressure, increases of the collagen I-to-collagen III ratio in collagen accumulation that due to more hypoxia , lipidsAtrophy and eventually amputation.  相似文献   

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Reactive oxygen formation plays a mechanistic role in the cardiotoxicity of doxorubicin, a chemotherapeutic agent that remains an important component of treatment programs for breast cancer and hematopoietic malignancies. To examine the role of doxorubicin-induced reactive oxygen species (ROS) in drug-related cardiac apoptosis, murine embryonic fibroblast cell lines were derived from the hearts of glutathione peroxidase 1 (Gpx-1) knockout mice. Cells from homozygous Gpx-1 knockout mice and parental animals were propagated with (Se+) and without (Se-) 100 nM sodium selenite. Activity levels of the peroxide detoxifying selenoprotein glutathione peroxidase (GSHPx) were marginally detectable (<1.6 nmol/min/mg) in fibroblasts from homozygous knockout animals whether or not cells were supplemented with selenium. GSHPx activity in Se- cells from parental murine fibroblasts was also <1.6 nmol/min/mg, whereas GSHPx levels in Se+ parental murine fibroblasts were 12.9 ± 2.7 nmol/min/mg (mean ± SE; P < 0.05). Catalase, superoxide dismutase, glutathione reductase, glutathione S-transferase, glucose 6-phosphate dehydrogenase, and reduced glutathione activities did not differ amongst the four cell lines. Reactive oxygen production increased from 908 ± 122 (arbitrary units) for untreated control cells to 1668 ± 54 following exposure to 1 μM doxorubicin for 24 h in parental fibroblasts not supplemented with selenium (P < 0.03); reactive oxygen formation in doxorubicin-treated parental fibroblasts propagated in selenium was 996 ± 69 (P = not significant compared to untreated control cells). Reactive oxygen levels in homozygous Gpx-1 knockout fibroblasts, irrespective of selenium supplementation status, were increased and equivalent to that in selenium deficient wild type fibroblasts. When cardiac fibroblasts were exposed to doxorubicin (0.05 μM) for 96 h and examined for cell cycle alterations by flow cytometry, and apoptosis by TUNEL assay, marked G2 arrest and TUNEL positivity were observed in knockout fibroblasts in the presence or absence of supplemental selenium, and in parental fibroblasts propagated without selenium. Parental fibroblasts propagated with selenium and exposed to the same concentration of doxorubicin demonstrated modest TUNEL positivity and substantially diminished amounts of low molecular weight DNA. These results were replicated in cardiac fibroblasts exposed to doxorubicin (1–2 μM) for 2 h (to mimic clinical drug dosing schedules) and examined 96 h following initiation of drug exposure. Doxorubicin uptake in cardiac fibroblasts was similar irrespective of the mRNA expression level or activity of GSHPx. These experiments suggest that the intracellular levels of doxorubicin-induced reactive oxygen species (ROS) are modulated by GSHPx and play an important role in doxorubicin-related apoptosis and altered cell cycle progression in murine cardiac fibroblasts.  相似文献   

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《Endocrine practice》2021,27(1):34-37
ObjectiveTreatment with immune-checkpoint inhibitors often results in endocrine immune-related adverse events (irAEs), affecting the pituitary, thyroid, adrenal, and parathyroid glands and pancreas. The mechanism underlying the endocrine irAEs has not been fully elucidated, and it remains unclear why endocrine organs are so commonly affected. In the present study, we evaluated immunostaining patterns of programmed death-ligand 1 (PD-L1) in normal endocrine tissues to determine whether increased expression may explain the predilection of endocrinopathies in patients treated with programmed cell death-1 inhibitors.MethodsNormal formalin-fixed paraffin-embedded endocrine tissues (pituitary, thyroid, adrenal, pancreas, and parathyroid) were collected from our hospital’s pathology tissue archive. The tissues were assessed for membranous and cytoplasmic PD-L1 immunostaining using the Dako 22C3 pharmDx assay on an automated staining platform.ResultsWe examined 49 endocrine tissues, including 12 thyroid, 5 pancreatic, 17 adrenal, 5 parathyroid, and 10 pituitary samples. Samples with less than 1% membranous PD-L1–positive cells were considered negative, while those with more than 1% of PD-L1 membranous staining were considered positive. Immunostaining result of immune-related cells was also evaluated, considering the cytoplasmic PD-L1–positive cells with the same cutoff of 1%. None of the endocrine tissues demonstrated PD-L1 positivity higher than 1% in the relevant cells.ConclusionWhile our results do not suggest a role of PD-L1 expression in the pathogenesis of endocrine irAEs, they may serve as a basis for future studies further investigating the mechanisms of autoimmune, inflammatory, or malignant endocrine conditions.  相似文献   

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The common marmoset Callithrix jacchus encodes two glutathione transferase (GST) enzymes with ketosteroid double-bond isomerase activity. The most active enzyme is CjaGST A3-3 showing a specific activity with 5-androsten-3,17-dione (Δ5-AD) of 62.1 ± 1.8 μmol min-1 mg-1, and a kcat value of 261 ± 49 s-1. The second ketosteroid isomerase CjaGST A1-1 has a 30-fold lower specific activity with Δ5-AD and a 37-fold lower kcat value. Thus, the marmoset CjaGST A3-3 would be the main contributor to the biosynthesis of the steroid hormones testosterone and progesterone, like the human ortholog HsaGST A3-3. Two residues differ in the H-site of the 91.4% sequence identical CjaGST A1-1 and CjaGST A3-3, and modeling of the structures suggests that the bulky phenyl ring of Phe111 in CjaGST A1-1 causes steric hindrance in the binding of the steroid substrate. Tributyltin acetate (IC50=0.16 ± 0.004 μM) and ethacrynic acid (IC50=3.3 ± 0.2 μM) were found to be potent inhibitors of CjaGST A3-3, as previously demonstrated with the human and equine orthologs.  相似文献   

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Disruption of epidermal barrier is an important trigger in abnormal cutaneous inflammation. Phospholipase C epsilon (PLCε), a Ras/Rap1 effector, is essential for regulating cytokines production in different types of skin inflammation. Our previous studies have demonstrated that elevated expression of PLCε participates in the psoriasis-like inflammation in PLCε overexpressing transgenic mice model, while the reduction in PLCε expression attenuates inflammatory responses in either TPA- or DNFB-induced cutaneous inflammation. Here, we determined the role of PLCε in cutaneous inflammation induced by acute abrogation of epidermal permeability barrier. In comparison to wild type controls, PLCε KO mice exhibited reduced ear swelling and infiltration of granulocytes after tape-stripping. Moreover, expression levels of pro-inflammatory cytokines (IL-1α, IL-1β), chemokines (CXCL-1, CXCL-2, CCL20), and antimicrobial peptides (S100 proteins, MBD3) were lower in PLCε-deficient versus wild type mice. Likewise, expression levels of cytokines and chemokines were also lower in PLCε deficient keratinocytes and fibroblasts following IL-22 stimulation in vitro. Furthermore, knockdown of PLCε with its siRNA decreased expression of IL-1α, CCL20, and S100 proteins, and MBD3 in HEK cultures. Collectively, these results suggested that PLCε mediated cytokine cascade induced by acute barrier disruption. IL-22 is likely the upstream of PLCε-mediated cytokine cascade following acute barrier disruption.  相似文献   

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Obesity is associated with inflammation, insulin resistance, and type 2 diabetes, which are major risk factors for CVD. One dietary component of ruminant animal foods, 10,12-conjugated linoleic acid (10,12 CLA), has been shown to promote weight loss in humans. Previous work has shown that 10,12 CLA is atheroprotective in mice by a mechanism that may be distinct from its weight loss effects, but this exact mechanism is unclear. To investigate this, we evaluated HDL composition and function in obese LDL receptor (Ldlr?/?) mice that were losing weight because of 10,12 CLA supplementation or caloric restriction (CR; weight-matched control group) and in an obese control group consuming a high-fat high-sucrose diet. We show that 10,12 CLA-HDL exerted a stronger anti-inflammatory effect than CR- or high-fat high-sucrose-HDL in cultured adipocytes. Furthermore, the 10,12 CLA-HDL particle (HDL-P) concentration was higher, attributed to more medium- and large-sized HDL-Ps. Passive cholesterol efflux capacity of 10,12 CLA-HDL was elevated, as was expression of HDL receptor scavenger receptor class B type 1 in the aortic arch. Murine macrophages treated with 10,12 CLA in vitro exhibited increased expression of cholesterol transporters Abca1 and Abcg1, suggesting increased cholesterol efflux potential of these cells. Finally, proteomics analysis revealed elevated Apoa1 content in 10,12 CLA-HDL-Ps, consistent with a higher particle concentration, and particles were also enriched with alpha-1-antitrypsin, an emerging anti-inflammatory and antiatherosclerotic HDL-associated protein. We conclude that 10,12 CLA may therefore exert its atheroprotective effects by increasing HDL-P concentration, HDL anti-inflammatory potential, and promoting beneficial effects on cholesterol efflux.  相似文献   

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《Translational oncology》2020,13(2):212-220
Ovarian cancer (OC) is an important cause of gynecologic cancer-related deaths. In Mexico, around 4700 new cases of OC are diagnosed per year and it represents the second cause of gynecological cancer mortality with more than 2700 deaths. Germline mutations in BRCA1/2 genes are present in 13–18% of OC cases. Few studies have evaluated the presence of mutations in BRCA genes in a population of OC Mexican patients and their relationship with clinical response and survival rates.A total of 179 OC patients were studied by molecular testing for BRCA1/2 through next-generation sequencing and multiplex ligation-dependent probe amplification. Recurrence-free survival (RFS) was estimated by the Kaplan–Meier method. BRCA mutation was detected in 33% of patients. A percentage of 66.1% were BRCA1 mutated and 33.9% were BRCA2 mutated. BRCA1 mutation carriers had a worst RFS compared with BRCA2 mutation carriers (37.6 [29–46.2] vs 72.7 [38.4–107.2]; P = 0.030). The most common mutation for BRCA1 was ex9-12del (28.2%) (Mexican founder mutation). The Mexican founder mutation had a better RFS than other BRCA1 mutations (86.1 [37.2–135.1] vs 34.5 [20.7–48.2]; P = 0.033). The presence of BRCA2 mutations in the ovarian cancer cluster region (OCCR) had a significantly better RFS than mutations in breast cancer cluster regions (BCCR) and not-related risk region (NRR) (NR vs 72.8 [39–106.6] vs 25.8 [8.3–43.2]; P = 0.013). These results demonstrate that the prevalence of BRCA1/2 positive patients in OC Mexican patients are the highest reported. Patients with mutations in BRCA2 have a better prognosis than those mutated in BRCA1. The Mexican founder mutation has an important role in clinical outcomes. These results highlight the importance to test all the HGSP (high-grade serous papillary) OC patients with or without cancer family history (CFH) in Mexican population.  相似文献   

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Human female infertility, 20% of which is idiopathic, is a public health problem for which better diagnostics and therapeutics are needed. A novel cause of infertility emerged from studies of female mice deficient in the HDL receptor gene (Scarb1). These mice are infertile and have high plasma HDL cholesterol (C) concentrations, due to elevated HDL-free cholesterol (FC), which transfers from HDL to all tissues. Previous studies have indicated that oral delivery of probucol, an HDL-lowering drug, to female Scarb1?/? mice reduces plasma HDL-C concentrations and rescues fertility. Additionally, serum opacity factor (SOF), a bacterial virulence factor, disrupts HDL structure, and bolus SOF injection into mice reduces plasma HDL-C concentrations. Here, we discovered that delivering SOF to female Scarb1?/? mice with an adeno-associated virus (AAVSOF) induces constitutive SOF expression, reduces HDL-FC concentrations, and rescues fertility while normalizing ovary morphology. Although AAVSOF did not alter ovary-FC content, the ovary-mol% FC correlated with plasma HDL-mol% FC in a fertility-dependent way. Therefore, reversing the abnormal plasma microenvironment of high plasma HDL-mol% FC in female Scarb1-/- mice rescues fertility. These data provide the rationale to search for similar mechanistic links between HDL-mol% FC and infertility and the rescue of fertility in women by reducing plasma HDL-mol% FC.  相似文献   

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