Testicular descent occurs in two consecutive stages: the transabdominal stage and the inguinoscrotal stage. Androgens play a crucial role in the second stage by influencing the development of the gubernaculum, a structure that pulls the testis into the scrotum. However, the mechanisms of androgen actions underlying many of the processes associated with gubernaculum development have not been fully elucidated. To identify the androgen-regulated genes, we conducted large-scale gene expression analyses on the gubernaculum harvested from luteinizing hormone/choriogonadotropin receptor knockout ( Lhcgr KO) mice, an animal model of inguinoscrotal testis maldescent resulting from androgen deficiency. We found that the expression of secreted protein acidic and rich in cysteine (SPARC)-related modular calcium binding 1 ( Smoc1 ) was the most severely suppressed at both the transcript and protein levels, while its expression was the most dramatically induced by testosterone administration in the gubernacula of Lhcgr KO mice. The upregulation of Smoc1 expression by testosterone was curtailed by the addition of an androgen receptor antagonist, flutamide. In addition, in vitro studies demonstrated that SMOC1 modestly but significantly promoted the proliferation of gubernacular cells. In the cultures of myogenic differentiation medium, both testosterone and SMOC1 enhanced the expression of myogenic regulatory factors such as paired box 7 ( Pax7 ) and myogenic factor 5 ( Myf5 ). After short-interfering RNA-mediated knocking down of Smoc1 , the expression of Pax7 and Myf5 diminished, and testosterone alone did not recover, but additional SMOC1 did. These observations indicate that SMOC1 is pivotal in mediating androgen action to regulate gubernaculum development during inguinoscrotal testicular descent.
Animals ; Male ; Mice ; Testis/growth & development* ; Mice, Knockout ; Androgens/pharmacology* ; Testosterone/pharmacology* ; Receptors, LH/metabolism* ; Calcium-Binding Proteins/metabolism*

Mouse spermatogenesis entails the maintenance and self-renewal of spermatogonial stem cells (SSCs), which require a complex web-like signaling network transduced by various cytokines. Although brain-derived neurotrophic factor (BDNF) is expressed in Sertoli cells in the testis, and its receptor tropomyosin receptor kinase B (TrkB) is expressed in the spermatogonial population containing SSCs, potential functions of BDNF for spermatogenesis have not been uncovered. Here, we generate BDNF conditional knockout mice and find that BDNF is dispensable for in vivo spermatogenesis and fertility. However, in vitro , we reveal that BDNF -deficient germline stem cells (GSCs) exhibit growth potential not only in the absence of glial cell line-derived neurotrophic factor (GDNF), a master regulator for GSC proliferation, but also in the absence of other factors, including epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), and insulin. GSCs grown without these factors are prone to differentiation, yet they maintain expression of promyelocytic leukemia zinc finger ( Plzf ), an undifferentiated spermatogonial marker. Inhibition of phosphoinositide 3-kinase (PI3K), mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK), and Src pathways all interfere with the growth of BDNF-deficient GSCs. Thus, our findings suggest a role for BDNF in maintaining the undifferentiated state of spermatogonia, particularly in situations where there is a shortage of growth factors.
Animals ; Male ; Brain-Derived Neurotrophic Factor/genetics* ; Spermatogonia/cytology* ; Mice ; Spermatogenesis/genetics* ; Mice, Knockout ; Cell Differentiation ; Glial Cell Line-Derived Neurotrophic Factor/genetics* ; Promyelocytic Leukemia Zinc Finger Protein/genetics* ; Cell Survival/physiology* ; Signal Transduction/physiology* ; Cell Proliferation/physiology*

Spermatogenesis is a fundamental process that requires a tightly controlled epigenetic event in spermatogonial stem cells (SSCs). The mechanisms underlying the transition from SSCs to sperm are largely unknown. Most studies utilize gene knockout mice to explain the mechanisms. However, the production of genetically engineered mice is costly and time-consuming. In this study, we presented a convenient research strategy using an RNA interference (RNAi) and testicular transplantation approach. Histone H3 lysine 9 (H3K9) methylation was dynamically regulated during spermatogenesis. As Jumonji domain-containing protein 1A (JMJD1A) and Jumonji domain-containing protein 2C (JMJD2C) demethylases catalyze histone H3 lysine 9 dimethylation (H3K9me2), we firstly analyzed the expression profile of the two demethylases and then investigated their function. Using the convenient research strategy, we showed that normal spermatogenesis is disrupted due to the downregulated expression of both demethylases. These results suggest that this strategy might be a simple and alternative approach for analyzing spermatogenesis relative to the gene knockout mice strategy.
Spermatogenesis/physiology* ; Animals ; Male ; Mice ; Epigenesis, Genetic ; Jumonji Domain-Containing Histone Demethylases/metabolism* ; Histones/metabolism* ; RNA Interference ; Testis/metabolism* ; Methylation ; Mice, Knockout ; Histone Demethylases

OBJECTIVES: To investigate the role of a neural pathway from oxytocin (OXT) neurons in the paraventricular hypothalamic nucleus (PVN) to γ-aminobutyric acid (GABA) neurons (GABAergic neurons) in the trigeminal nucleus caudalis (TNC) in regulating pain sensitization in a mouse model of chronic migraine and to explore the underlying mechanisms. METHODS: A chronic migraine mouse model was established by intraperitoneal injection of nitroglycerin (NTG, 1 mg/mL, 10 mg/kg) on days 1, 3, 5, 7, and 9. The study consisted of four parts: PartⅠ: 24 male wild-type C57BL/6J mice were divided into four groups (n=6 in each), receiving single or repeated injection of NTG or saline, respectively. Immunofluorescence was used to detect c-Fos and OXT expression in the PVN. Part Ⅱ: 6 male OXT-Cre transgenic C57BL/6J mice were used for anterograde monosynaptic tracing combined with RNAscope and immunofluorescence to identify neural projections from PVN OXT neurons to TNC GABAergic neurons. Part Ⅲ: 30 male OXT-Cre transgenic C57BL/6J mice were bilaterally injected Cre-dependent chemogenetic activation virus into the PVN. These mice were randomly divided into five groups, with six mice in each group. Mice in the clozapine N-oxide (CNO) group and the control group were intra-peritoneally injected with 0.1 mg/mL of CNO solution (1 mg/kg) and the same volume of isotonic normal saline, respectively. 3 hours after the injection, the brain tissues were harvest and c-Fos immunofluorescence staining was performed to verify the efficiency of chemogenetic activation virus. Mice in the model control group and the CNO activated model group were subjected to chronic migraine modeling, with bilateral TNC injection of isotonic normal saline and CNO, respectively, on day 10. The mice in the negative control group were bilaterally intra-TNC injected with isotonic normal saline. After 30 minutes, the Von-Frey filament and acetone tests were used to assess the mechanical pain threshold and cold pain response time in the periorbital region of the mice in these three groups. Part Ⅳ: 24 male OXT-Cre transgenic C57BL/6J mice were bilaterally injected with the Cre-dependent chemogenetic activation virus into the PVN. These mice were randomly divided into four groups, with six mice in each group. Mice in the model control group, the CNO activated model group and the atosiban group were subjected to chronic migraine modeling. On day 10, mice in the negative control group and the model control group were intraperitoneally injected with isotonic normal saline, while mice in the CNO activated model group and the atosiban group were intraperitoneally injected with CNO. After 15 minutes, mice in the atosiban group were bilaterally intra-TNC injected with atosiban, while mice in other three groups were bilaterally intra-TNC injected with isotonic normal saline containing 1% dimethyl sulfoxide. After 15 minutes, the Von-Frey filament and acetone tests were used to assess the mechanical pain threshold and cold pain response time in the periorbital region of the mice. The GABA content in the bilateral TNC was detected by high-performance liquid chromatography (HPLC). RESULTS: Mice with chronic migraine models exhibited reduced periorbital mechanical pain thresholds and increased periorbital cold pain reaction time, accompanied by an increase in both the number of c-Fos⁺ neurons and the percentage of c-Fos⁺ OXT neurons in the PVN (all P<0.05). The anterograde tracing virus and RNAscope combined with immunofluorescence staining showed that PVN OXT neurons projected to TNC GABAergic neurons. Immuno-fluorescence staining demonstrated that compared with the control group, the percentage of c-Fos⁺ OXT neurons in the PVN of CNO group increased (P<0.05). In bilateral intra-TNC drug administration experiments, compared with the model control group, the periorbital mechanical pain threshold increased, and the periorbital cold pain reaction time decreased in the CNO activated model group (both P<0.05). In intraperitoneal drug administration experiments, compared with the CNO activate model group, the periorbital mechanical pain threshold decreased, and the periorbital cold pain reaction time increased in the atosiban group (both P<0.05). HPLC analysis showed that, compared with the negative control group, the model control group and the atosiban group, GABA level of TNC in the CNO activated model group increased (all P<0.05). CONCLUSIONS PVN OXT neurons exert a descending facilitatory effect on GABAergic neurons in the TNC via OXT release, thereby ameliorating pain sensitization in chronic migraine.
Animals ; Paraventricular Hypothalamic Nucleus/physiopathology* ; Male ; Mice, Inbred C57BL ; Migraine Disorders/physiopathology* ; Mice ; GABAergic Neurons/physiology* ; Oxytocin/physiology* ; Disease Models, Animal ; Neurons/physiology* ; Mice, Transgenic ; Neural Pathways ; Chronic Disease

OBJECTIVE: To explore the effect and mechanism of DNA methyltransferase 1 (DNMT1) knockout on the inhibition of acute myeloid leukemia (AML) by natural killer (NK) cells. METHODS: The peripheral blood NK cells of AML patients and controls were collected, and the mRNA and protein level of DNMT1 were measured by PCR and Western blot, respectively. The DNMT1 knockout mice were constructed to obtain NK^DNMT1-/- cells. The NK cells were stimulated with interleukin (IL)-12, IL-15, and IL-18 to construct memory NK cells, and then the interferon-γ (IFN-γ) levels were measured by ELISA. After co-culturing with memory NK cells and HL60 cells, the killing effect of NK^DNMT1-/- cells on HL60 cells was detected by LDH assay. Then, the HL60 cell apoptosis and NK cell NKG2D level were measured by flow cytometry. The perforin and granzyme B protein levels of NK cells were measured by Western blot. The AML model mice were constructed by injecting HL60 cells into the tail vein, meanwhile, memory NK cells were also injected, and then the mouse weights, CD33 positive rates, and survival time were detected. RESULTS: The mRNA and protein levels of DNMT1 in NK cells of AML patients were significantly higher than those in the control group (both P < 0.01), while the IFN-γ level induced by interleukin was significantly lower than that in the control group (P < 0.05). Compared with NK^DNMT1+/+ cells, the ability of NK^DNMT1-/- cells to secrete IFN-γ after interleukin stimulation was significantly increased (P < 0.05). The killing and apoptosis-inducing effects of NK^DNMT1-/- cells on HL60 cells were significantly stronger than those of NK^DNMT1+/+ cells (both P < 0.05). The NKG2D level and expression of perforin and granzyme B of NK^DNMT1-/- cells were significantly increased compared with NK^DNMT1+/+ cells (all P < 0.05). Compared with AML mice injected with NK^DNMT1+/+ cells, AML mice injected with NK^DNMT1-/- cells showed significantly increased body weight, decreased CD33 positive rate, and prolonged survival time (all P < 0.05). CONCLUSION Knocking out DNMT1 can enhance the inhibitory effect of NK cells on AML, which may be related to enhancing NK cell memory function.
Killer Cells, Natural/metabolism* ; Animals ; Leukemia, Myeloid, Acute ; Humans ; DNA (Cytosine-5-)-Methyltransferase 1 ; Mice ; Mice, Knockout ; HL-60 Cells ; Apoptosis ; Interferon-gamma/metabolism* ; Granzymes/metabolism* ; Perforin/metabolism* ; NK Cell Lectin-Like Receptor Subfamily K/metabolism*

OBJECTIVE: To investigate the regulatory effect of Wip1 phosphatase on hematopoietic function in the mouse spleen. METHODS: Wip1 knockout mice were bred, and the effect of Wip1 deletion on the proportion and number of hematopoietic stem/progenitor cells, as well as their mature subsets in mouse spleen was detected by flow cytometry. The Proteome Profiler^TM antibody array was used to analyze the role of Wip1 deletion on the expression of inflammatory cytokines in CD45^highCD11b⁺ myeloid cells sorted from mouse spleen. RESULTS: Wip1 deletion resulted in smaller size and significant reduction of cell number in the mouse spleen. The absolute numbers of hematopoietic stem/progenitor cells were decreased. Meanwhile, the absolute number of T and B lymphocytes also significantly declined. However, the proportion of erythroid progenitors and erythroid cells at various stage significantly increased, but the number of mature erythroid cells decreased. Furthermore, the myeloid cells and their subsets neutrophils, monocytes, CD45^highCD11b⁺ and CD45^lowCD11b⁺ were all reduced. CD45^highCD11b⁺ myeloid cells displayed proinflammatory phenotype in the spleen. CONCLUSION Wip1 gene deletion impairs normal hematopoietic function in the mouse spleen, leading to a significant reduction of mature hematopoietic cells of various lineages, and proinflammatory phenotype in CD45^highCD11b⁺ myeloid cells.
Animals ; Mice ; Spleen/cytology* ; Mice, Knockout ; Hematopoietic Stem Cells/cytology* ; Myeloid Cells/cytology* ; Protein Phosphatase 2C ; Hematopoiesis ; Flow Cytometry

BACKGROUND: Chronic kidney disease (CKD) is associated with common pathophysiological processes, such as inflammation and fibrosis, in both the heart and the kidney. However, the underlying molecular mechanisms that drive these processes are not yet fully understood. Therefore, this study focused on the molecular mechanism of heart and kidney injury in CKD. METHODS: We generated an microRNA (miR)-26a knockout (KO) mouse model to investigate the role of miR-26a in angiotensin (Ang)-II-induced cardiac and renal injury. We performed Ang-II modeling in wild type (WT) mice and miR-26a KO mice, with six mice in each group. In addition, Ang-II-treated AC16 cells and HK2 cells were used as in vitro models of cardiac and renal injury in the context of CKD. Histological staining, immunohistochemistry, quantitative real-time polymerase chain reaction (PCR), and Western blotting were applied to study the regulation of miR-26a on Ang-II-induced cardiac and renal injury. Immunofluorescence reporter assays were used to detect downstream genes of miR-26a, and immunoprecipitation was employed to identify the interacting protein of LIM and senescent cell antigen-like domain 1 (LIMS1). We also used an adeno-associated virus (AAV) to supplement LIMS1 and explored the specific regulatory mechanism of miR-26a on Ang-II-induced cardiac and renal injury. Dunnett's multiple comparison and t -test were used to analyze the data. RESULTS: Compared with the control mice, miR-26a expression was significantly downregulated in both the kidney and the heart after Ang-II infusion. Our study identified LIMS1 as a novel target gene of miR-26a in both heart and kidney tissues. Downregulation of miR-26a activated the LIMS1/integrin-linked kinase (ILK) signaling pathway in the heart and kidney, which represents a common molecular mechanism underlying inflammation and fibrosis in heart and kidney tissues during CKD. Furthermore, knockout of miR-26a worsened inflammation and fibrosis in the heart and kidney by inhibiting the LIMS1/ILK signaling pathway; on the contrary, supplementation with exogenous miR-26a reversed all these changes. CONCLUSIONS Our findings suggest that miR-26a could be a promising therapeutic target for the treatment of cardiorenal injury in CKD. This is attributed to its ability to regulate the LIMS1/ILK signaling pathway, which represents a common molecular mechanism in both heart and kidney tissues.
Animals ; MicroRNAs/metabolism* ; Angiotensin II/toxicity* ; Mice ; Renal Insufficiency, Chronic/chemically induced* ; Mice, Knockout ; Disease Models, Animal ; Male ; Signal Transduction/genetics* ; LIM Domain Proteins/genetics* ; Mice, Inbred C57BL ; Cell Line ; Humans

BACKGROUND: Increasing evidence indicates that oxidative stress and interferon γ (IFNγ)-driven cellular immune responses are responsible for the pathogenesis of vitiligo. However, the connection between oxidative stress and the local production of IFNγ in early vitiligo remains unexplored. The aim of this study was to identify the mechanism underlying the production of IFNγ by mast cells and its impact on vitiligo pathogenesis. METHODS: Skin specimens from the central, marginal, and perilesional skin areas of active vitiligo lesions were collected to characterize changes of mast cells, CD8 + T cells, and IFNγ-producing cells. Cell supernatants from hydrogen peroxide (H 2 O 2 )-treated keratinocytes (KCs) were harvested to measure levels of soluble stem cell factor (sSCF) and matrix metalloproteinase (MMP)-9. A murine vitiligo model was established using Mas-related G protein-coupled receptor-B2 (MrgB2, mouse ortholog of human MrgX2) conditional knockout (MrgB2 -/- ) mice to investigate IFNγ production and inflammatory cell infiltrations in tail skin following the challenge with tyrosinase-related protein (Tyrp)-2 180 peptide. Potential interactions between the Tyrp-2 180 peptide and MrgX2 were predicted using molecular docking. The siRNAs targeting MrgX2 and the calcineurin inhibitor FK506 were also used to examine the signaling pathways involved in mast cell activation. RESULTS: IFNγ-producing mast cells were closely aligned with the recruitment of CD8 + T cells in the early phase of vitiligo skin. sSCF released by KCs through stress-enhanced MMP9-dependent proteolytic cleavage recruited mast cells into sites of inflamed skin (Perilesion vs . lesion, 13.00 ± 4.00/high-power fields [HPF] vs . 26.60 ± 5.72/HPF, P <0.05). Moreover, IFNγ-producing mast cells were also observed in mouse tail skin following challenge with Tyrp-2 180 (0 h vs . 48 h post-recall, 0/HPF vs . 3.80 ± 1.92/HPF, P <0.05). The IFNγ + mast cell and CD8 + T cell counts were lower in the skin of MrgB2 -/- mice than in those of wild-type mice (WT vs . KO 48 h post-recall, 4.20 ± 0.84/HPF vs . 0.80 ± 0.84/HPF, P <0.05). CONCLUSION Mast cells activated by MrgX2 serve as a local IFNγ producer that bridges between innate and adaptive immune responses against MCs in early vitiligo. Targeting MrgX2-mediated mast cell activation may represent a new strategy for treating vitiligo.
Vitiligo/metabolism* ; Mast Cells/immunology* ; Animals ; Interferon-gamma/metabolism* ; Mice ; Humans ; Melanocytes/metabolism* ; Receptors, G-Protein-Coupled/genetics* ; Mice, Knockout ; Mice, Inbred C57BL ; Male ; Female ; Matrix Metalloproteinase 9/metabolism* ; Stem Cell Factor/metabolism*

BACKGROUND: Immunosuppression is closely related to the pathogenesis of sepsis, but the underlying mechanisms have not yet been fully elucidated. In this study, we aimed to examine the role of the Sterile Alpha Motif, Src Homology 3 domain and nuclear localization signal 1 (SAMSN1) in sepsis and elucidate its potential molecular mechanism in sepsis induced immunosuppression. METHODS: RNA sequencing databases were used to validate SAMSN1 expression in sepsis. The impact of SAMSN1 on sepsis was verified using gene knockout mice. Flow cytometry was employed to delineate how SAMSN1 affects immunity in sepsis, focusing on immune cell types and T cell functions. Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9)-mediated gene editing in RAW264.7 macrophages enabled interrogation of SAMSN1 's regulatory effects on essential macrophage functions, including cell proliferation and phagocytic capacity. The mechanism of SAMSN1 in the interaction between macrophages and T cells was investigated using the RAW264.7 cell line and primary cell lines. RESULTS: SAMSN1 expression was significantly increased in patients with sepsis and was positively correlated with sepsis mortality. Genetic deletion of Samsn1 in murine sepsis model improved T cell survival, elevated T cell cytolytic activity, and activated T cell signaling transduction. Concurrently, Samsn1 knockout augmented macrophage proliferation capacity and phagocytic efficiency. In macrophage, SAMSN1 binds to Kelch-like epichlorohydrin-associated protein 1 (KEAP1), causing nuclear factor erythroid 2-related factor 2 (NRF2) to dissociate from the KEAP1-NRF2 complex and translocate into the nucleus. This promotes the transcription of the coinhibitory molecules CD48/CD86/carcinoembryonic antigen related cell adhesion molecule 1 (CEACAM1), which bind to their corresponding receptors natural killer cell receptor 2B4/CD152/T cell immunoglobulin and mucin domain-containing protein 3 (TIM3) on the surface of T cells, inducing T-cell exhaustion. CONCLUSIONS SAMSN1 deletion augmented adaptive T cell immunity and macrophage phagocytic-proliferative dual function. Furthermore, it mediates the KEAP1-NRF2 axis, which affects the expression of coinhibitory molecules on macrophages, leading to T-cell exhaustion. This novel immunosuppression mechanism potentially provides a candidate molecular target for sepsis immunotherapy.
Animals ; NF-E2-Related Factor 2/metabolism* ; Mice ; Macrophages/immunology* ; Sepsis/metabolism* ; Kelch-Like ECH-Associated Protein 1/genetics* ; T-Lymphocytes/immunology* ; Humans ; Signal Transduction/physiology* ; RAW 264.7 Cells ; Mice, Knockout ; Mice, Inbred C57BL ; Male ; Flow Cytometry ; T-Cell Exhaustion

BACKGROUND: Epoxyeicosatrienoic acids (EETs), which are metabolites of arachidonic acid catalyzed by cytochrome P450 epoxygenase, are degraded into inactive dihydroxyeicosatrienoic acids by soluble epoxide hydrolase (sEH). Many studies have revealed that sEH gene deletion exerts protective effects against diabetes. Vascular calcification is a common complication of diabetes, but the potential effects of sEH on diabetic vascular calcification are still unknown. METHODS: The level of aortic calcification in wild-type and Ephx2-/- C57BL/6 diabetic mice induced with streptozotocin was evaluated by measuring the aortic calcium content through alizarin red staining, immunohistochemistry staining, and immunofluorescence staining. Mouse vascular smooth muscle cell lines (MOVAS cells) treated with β-glycerol phosphate (0.01 mol/L) plus advanced glycation end products (50 mg/L) were used to investigate the effects of sEH inhibitors or sEH knockdown and EETs on the calcification of vascular smooth muscle cells, which was detected by Western blotting, alizarin red staining, and Von Kossa staining. RESULTS: sEH gene deletion significantly inhibited diabetic vascular calcification by increasing levels of EETs in the aortas of mice. EETs (especially 11,12-EET and 14,15-EET) efficiently prevented the osteogenic transdifferentiation of MOVAS cells by decreasing nidogen-2 (NID2) expression. Interestingly, suppressing sEH activity by small interfering ribonucleic acid or specific inhibitors did not block osteogenic transdifferentiation of MOVAS cells induced by β-glycerol phosphate and advanced glycation end products. NID2 overexpression significantly abolished the inhibitory effect of sEH gene deletion on diabetic vascular calcification. Moreover, NID2 overexpression mediated by adeno-associated virus 9 vectors markedly increased insulin-like growth factor 2 (IGF2) and phospho-ERK1/2 expression in MOVAS cells. Overall, sEH gene knockout inhibited diabetic vascular calcification by decreasing aortic NID2 expression and, then, inactivating the downstream IGF2-ERK1/2 signaling pathway. CONCLUSIONS sEH gene deletion markedly inhibited diabetic vascular calcification through repressed osteogenic transdifferentiation of vascular smooth muscle cells mediated by increased aortic EET levels, which was associated with decreased NID2 expression and inactivation of the downstream IGF2-ERK1/2 signaling pathway.
Animals ; Mice ; Vascular Calcification/metabolism* ; Mice, Inbred C57BL ; Epoxide Hydrolases/metabolism* ; Diabetes Mellitus, Experimental/genetics* ; Male ; Gene Deletion ; MAP Kinase Signaling System/genetics* ; Cell Line ; Immunohistochemistry ; Muscle, Smooth, Vascular/metabolism* ; Signal Transduction/genetics* ; Mice, Knockout