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P2X receptors, a subfamily of ligand-gated ion channels activated by extracellular ATP, are implicated in various physiopathological processes, including inflammation, pain perception, and immune and respiratory regulations. Structural determinations using crystallography and cryo-EM have revealed that the extracellular three-dimensional architectures of different P2X subtypes across various species are remarkably identical, greatly advancing our understanding of P2X activation mechanisms. However, structural studies yield paradoxical architectures of the intracellular domain (ICD) of different subtypes (e.g., P2X3 and P2X7) at the apo state, and the role of the ICD in P2X functional regulation remains unclear. Here, we propose that the P2X3 receptor's ICD has an apo state conformation similar to the open state but with a less tense architecture, containing allosteric sites that influence P2X3's physiological and pathological roles. Using covalent occupancy, engineered disulfide bonds and voltage-clamp fluorometry, we suggested that the ICD can undergo coordinated motions with the transmembrane domain of P2X3, thereby facilitating channel activation. Additionally, we identified a novel P2X3 enhancer, PSFL77, and uncovered its potential allosteric site located in the 1α3ß domain of the ICD. PSFL77 modulated pain perception in P2rx3+/+, but not in P2rx3-/-, mice, indicating that the 1α3ß, a "tunable" region implicated in the regulation of P2X3 functions. Thus, when P2X3 is in its apo state, its ICD architecture is fairly ordered rather than an unstructured outward folding, enabling allosteric modulation of the signaling of P2X3 receptors.
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Sítio Alostérico , Domínios Proteicos , Receptores Purinérgicos P2X3 , Animais , Humanos , Masculino , Camundongos , Trifosfato de Adenosina/metabolismo , Regulação Alostérica , Células HEK293 , Camundongos Endogâmicos C57BL , Receptores Purinérgicos P2X3/metabolismo , Receptores Purinérgicos P2X3/química , Receptores Purinérgicos P2X3/genéticaRESUMO
Human spermatogonial stem cells (SSCs) are essential for spermatogenesis and male fertility. However, molecular mechanisms regulating fate determinations of human SSCs remain elusive. In this study, we revealed that KLF2 decreased the proliferation, DNA synthesis, and colonization of human SSCs as well as increased apoptosis of these cells. We identified and demonstrated that GJA1 was a target gene for KLF2 in human SSCs. Notably, KLF2 overexpression rescued the reduction of proliferation of human SSCs caused by GJA1 silencing as well as the enhancement of apoptosis of human SSCs. Abnormalities in the higher level of KLF2 and/or KIF2 mutations might lead to male infertility. Collectively, these results implicate that KLF2 inhibits proliferation of human SSCs and enhances their apoptosis by targeting GJA1. This study thus provides novel genetic mechanisms underlying human spermatogenesis and azoospermia, and it offers new endogenous targets for treating male infertility.
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ATP citrate lyase (ACLY), a strategic metabolic enzyme that catalyzes the glycolytic to lipidic metabolism, has gained increasing attention as an attractive therapeutic target for hyperlipidemia, cancers and other human diseases. Despite of continual research efforts, targeting ACLY has been very challenging. In this field, most reported ACLY inhibitors are "substrate-like" analogues, which occupied with the same active pockets. Besides, some ACLY inhibitors have been disclosed through biochemical screening or high throughput virtual screening. In this review, we briefly summarized the cancer-related functions and the recent advance of ACLY inhibitors with a particular focus on the SAR studies and their modes of action. We hope to provide a timely and updated overview of ACLY and the discovery of new ACLY inhibitors.
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ATP Citrato (pro-S)-Liase , Neoplasias , Humanos , ATP Citrato (pro-S)-Liase/metabolismo , Neoplasias/metabolismo , Metabolismo dos LipídeosRESUMO
Diabetic nephropathy (DN) has become one of the major fatal factors in diabetic patients. The aim of this study was to elucidate the function and mechanism by which berberine exerts renoprotective effects in DN. In this work, we first demonstrated that urinary iron concentration, serum ferritin and hepcidin levels were increased and total antioxidant capacity was significantly decreased in DN rats, while these changes could be partially reversed by berberine treatment. Berberine treatment also alleviated DN-induced changes in the expression of proteins involved in iron transport or iron uptake. In addition, berberine treatment also partially blocked the expression of renal fibrosis markers induced by DN, including MMP2, MMP9, TIMP3, ß-arrestin-1, and TGF-ß1. In conclusion, the results of this study suggest that berberine may exert renoprotective effects by ameliorating iron overload and oxidative stress and reducing DN.
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Berberina , Diabetes Mellitus , Nefropatias Diabéticas , Sobrecarga de Ferro , Ratos , Animais , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Rim/metabolismo , Berberina/farmacologia , Berberina/metabolismo , Ratos Sprague-Dawley , Estresse Oxidativo , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/metabolismo , Ferro/metabolismo , Diabetes Mellitus/metabolismoRESUMO
Coxsackievirus B3 (CVB3) is a leading cause of viral myocarditis, but no effective treatment strategy against CVB3 is available. Viruses lack an inherent metabolic system and thus depend on host cellular metabolism for their benefit. In this study, we observed that CVB3 enhanced glycolysis in H9c2 rat cardiomyocytes and HL-1 mouse cardiomyocytes. Therefore, three key glycolytic enzymes, namely, hexokinase 2 (HK2), muscle phosphofructokinase (PFKM), and pyruvate kinase M2 (PKM2), were measured in CVB3-infected H9c2 and HL-1 cells. Expression levels of HK2 and PFKM, but not PKM2, were increased in CVB3-infected H9c2 cells. All three key glycolytic enzymes showed elevated expression in CVB3-infected HL-1 cells. To further investigate this, we used 2 deoxyglucose, sodium citrate, and shikonin as glycolysis inhibitors for HK2, PFKM, and PKM2, respectively. Glycolysis inhibitors significantly reduced CVB3 replication, while the glycolysis enhancer dramatically promoted it. In addition, glycolysis inhibitors decreased autophagy and accelerated autophagosome degradation. The autophagy inducer eliminated partial inhibition effects of glycolysis inhibitors on CVB3 replication. These results demonstrate that CVB3 infection enhances glycolysis and thus benefits viral replication.
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BACKGROUND: Human papillomavirus (HPV) infections were the main cause of anogenital cancers and warts. HPV 6/11/16/18 vaccines provide protection against the high-risk types of HPV responsible for 70% of cervical cancers and 90% of genital warts. This randomized, blinded, non-inferiority phase III trial was to determine whether immunogenicity and tolerability would be non-inferior among women after receiving two novel 4- and 9-valent HPV vaccines (4vHPV, HPV 6/11/16/18; 9vHPV, HPV 6/11/16/18/31/33/45/52/58) compared with those receiving Gardasil 4 (4-valent). METHODS: 1680 females between 20 and 45 years were randomized in a 2:1:1 ratio to 20-26, 27-35, or 36-45 y groups. Subjects then equally assigned to receive 4vHPV, 9vHPV or Gardasil 4 (control) vaccine at months 0, 2, and 6. End points included non-inferiority of HPV-6/11/16/18 antibodies for 4vHPV versus control, and 9vHPV versus control and safety. The immunogenicity non-inferiority was pre-defined as the lower bound of 95% confidence interval (CI) of seroconversion rate (SCR) difference > -10% and the lower bound of 95% CI of geometric mean antibody titer (GMT) ratio > 0.5. RESULTS: Among the three vaccine groups, more than 99% of the participants seroconverted to all 4 HPV types. The pre-specified statistical non-inferiority criterion for the immunogenicity hypothesis was met: all the lower bounds of 95% CIs on SCR differences exceeded -10% for each vaccine HPV type and the corresponding lower bounds of 95% CIs for GMT ratios > 0.5. Across vaccination groups, the most common vaccination reaction were injection-site adverse events (AEs), including pain, swelling, and redness. General and serious AEs were similar in the three groups. There were no deaths. CONCLUSIONS: This study demonstrated that the novel 4- and 9-valent HPV vaccination was highly immunogenic and generally well tolerated, both of which were non-inferior to Gardasil 4 in immunogenicity and safety.
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Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/efeitos adversos , Infecções por Papillomavirus/prevenção & controle , Gammapapillomavirus , Anticorpos Antivirais , Neoplasias do Colo do Útero/prevenção & controle , Papillomaviridae , China , Imunogenicidade da VacinaRESUMO
Studies on gene regulation and signaling transduction pathways of human spermatogonial stem cells (SSCs) are of the utmost significance for unveiling molecular mechanisms underlying human spermatogenesis and gene therapy of male infertility. We have demonstrated, for the first time, that RNF144B stimulated cell proliferation and inhibited the apoptosis of human SSCs. The target of RNF144B was identified as FCER2 by RNA sequencing. We revealed that RNF144B interacted with FCER2 by immunoprecipitation. Consistently, overexpression of FCER2 reversed the phenotype of proliferation and apoptosis of human SSCs caused by RNF144B knockdown. Interestingly, FCER2 pulled down N2ICD (NOTCH2 intracellular domain), while N2ICD could bind to FCER2 in human SSCs. The levels of NOTCH2, FCER2, HES1, and HEY1 were reduced by RNF144B siRNA in human SSCs. Significantly, RNF144B was expressed at a lower level in nonobstructive azoospermia (NOA) patients than in the obstructive azoospermia (OA) patients with normal spermatogenesis, and 52 patients with heterozygous mutations of RNF144B were detected in 1,000 NOA patients. These results implicate that RNF144B promotes the proliferation of human SSCs and suppresses their apoptosis via the FCER2/NOTCH2/HES1 pathway and that the abnormality of RNF144B is associated with spermatogenesis failure. This study thus provides novel molecular mechanisms regulating the fate determinations of human SSCs, and it offers new biomarkers for the diagnosis and treatment of male infertility.
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Células-Tronco Germinativas Adultas , Apoptose , Azoospermia , Infertilidade Masculina , Espermatogênese , Células-Tronco Germinativas Adultas/metabolismo , Apoptose/genética , Azoospermia/complicações , Azoospermia/genética , Proliferação de Células/genética , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Infertilidade Masculina/etiologia , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Masculino , Receptor Notch2/genética , Receptor Notch2/metabolismo , Receptores de IgE/metabolismo , Espermatogênese/genética , Fatores de Transcrição HES-1/genética , Fatores de Transcrição HES-1/metabolismoRESUMO
BACKGROUND: Interleukin-33 (IL-33) is a member of the interleukin-1 family, which is reported to be important across a range of diseases. However, the mechanisms underlying IL-33/ST2 axis in infectious diseases have not yet been fully addressed. METHODS: We established both lipopolysaccharide (LPS)-induced injuryin T cells and Listeria monocytogenes (Lm) infection model to determine the effect of IL-33 on infectious immunity. RESULTS: The T cell proliferation was inhibited by LPS while IL-33 could reverse the outcome. Further, apoptosis was significantly promoted after serum stimulation (ST)2 knockdown, suggesting IL-33, acting through its receptor ST2, may attenuate the inhibitory effect of LPS on T cells through the apoptotic signaling pathway. In this study, we also identified an IL-33-mediated mechanism of T cell differentiation in pregnant mice infected with Lm. Here, we observed the elevated expression of IL-33 in pregnant mice infected with Lm. Furthermore, we revealed that blocking IL-33 markedly decreased the abortion rate and placental bacterial load, but weakened placental inflammatory repair, by inhibiting Th2 cell-mediated immune responses and relatively intensifying Th1-dominent immunoreaction. CONCLUSIONS: These findings reveal a previously unidentified mechanism underlying IL-33/ST2 axis. IL-33 signaling and targeting T cell-mediated immunity may present a new therapeutic strategy for the treatment of infectious diseases.
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Proteína 1 Semelhante a Receptor de Interleucina-1 , Interleucina-33 , Listeria , Listeriose , Linfócitos T , Animais , Feminino , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Interleucina-33/genética , Lipopolissacarídeos , Listeriose/imunologia , Ativação Linfocitária , Camundongos , Placenta , Gravidez , Linfócitos T/imunologiaRESUMO
BACKGROUND: Angiotensin (Ang) (1-7) is a vasodilator peptide that ameliorates microcirculation dysfunction, increases telomerase activity in cells, and exerts vasodilatory, anti-inflammatory, antioxidative stress, and antiapoptotic effects. Mitochondrial human telomerase reverse transcriptase (hTERT) plays an important role in the processes of antiapoptosis, antioxidative stress, and immortalization. This study aimed to investigate the effect of Ang(1-7) on the mitochondrial translocation of hTERT. METHODS: An in vitro model of lipopolysaccharide (LPS)-induced inflammation was established in human umbilical vein endothelial cells (HUVECs). Ang(1-7) was added to cells 30 min before LPS stimulation. The Ang(1-7)/Mas receptor antagonist A779 plus Ang(1-7) were added to the cells 30 min before LPS stimulation. The translocase outer membrane (TOM)20-overexpression HUVECs (HUVEC-TOM20OE), TOM20-knockdown HUVECs (HUVEC-TOM20KD), and the corresponding negative control cell lines were constructed by lentiviral transfection of HUVECs. Cells subjected to LPS stimulation alone, LPS plus Ang(1-7), LPS plus Ang(1-7) and A779, vehicle and no treatment were termed the LPS group, LPS + A group, LPS + A + A779 group, Con group and Neg group, respectively. Immunofluorescence staining was used to detect the distribution of hTERT in the nuclei and mitochondria of HUVECs and to locate TOM20, TOM40, and translocase inner membrane (TIM)23 in the mitochondria. The protein expression levels of total hTERT, mitochondrial hTERT, TOM20, TOM40, and TIM23 were measured by Western blot. The mRNA expression levels of hTERT, TOM20, TOM40, and TIM23 were assessed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). RESULTS: hTERT colocalized with TOM40, TOM20 and TIM23 in the mitochondria. The mitochondrial hTERT protein level of the LPS + A group was significantly greater than that of the LPS group (P = 0.001), and the LPS group showed significantly increased expression of mitochondrial hTERT compared with that of the control group (P = 0.001). No significant difference in the level of total hTERT was observed between the LPS + A and LPS groups. The mitochondrial hTERT protein level of the LPS + A + A779 group was significantly lower than that of the LPS + A group (P = 0.021). The protein level of mitochondrial hTERT in HUVEC-TOM20KD treated with or without LPS alone or LPS + A was significantly decreased compared with the corresponding groups of control HUVECs (HUVEC-TOM20KD-Con vs. HUVEC-Con, P = 0.035; HUVEC-TOM20KD-LPS vs. HUVEC-LPS, P = 0.003; HUVEC-TOM20KD-LPS + A vs. HUVEC-LPS + A, P = 0.001), and treatment with Ang(1-7) did not restore the downregulation of mitochondrial hTERT in HUVEC-TOM20KD. HUVEC-TOM20OE showed a significantly increased level of mitochondrial hTERT (HUVEC-TOM20OE-Con vs. HUVEC-Con, P = 0.010), which was further elevated by Ang(1-7) stimulation (HUVEC-TOM20OE-LPS + A vs. HUVEC-TOM20OE-Con, P = 0.011). Lastly, the protein expression levels of TOM40 (HUVEC-TOM20KD-Con vs. HUVEC-Con, P = 0.007) and TIM23 (HUVEC-TOM20KD-Con vs. HUVEC-Con, P = 0.001) were significantly increased in HUVEC-TOM20KD in comparison to HUVECs. CONCLUSIONS: Ang(1-7) effectively promoted mitochondrial translocation of hTERT in HUVECs via TOM20, indicating that hTERT may be transported to the mitochondria through the TOM20 complex. In addition, A779 could block the effects of Ang(1-7) in HUVECs.
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Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial/metabolismo , Telomerase , Angiotensina I , Angiotensina II/farmacologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Lipopolissacarídeos/farmacologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Fragmentos de Peptídeos , Telomerase/genética , Telomerase/metabolismo , Telomerase/farmacologiaRESUMO
Ferroptosis, an iron-dependent type of regulated cell death, is triggered by the accumulation of lethal lipid peroxides. Due to its potential in exploring disease progression and highly targeted therapies, it is still a widely discussed topic nowadays. In recent studies, it was found that ferroptosis was induced when testicular tissue was exposed to some high-risk factors, such as cadmium (Cd), busulfan, and smoking accompanied by a variety of reproductive damage characteristics, including changes in the specific morphology and ferroptosis-related features. In this literature-based review, we summarize the related mechanisms of ferroptosis and elaborate upon its relationship network in the male reproductive system in terms of three significant events: the abnormal iron metabolism, dysregulation of the Cyst(e)ine/GSH/GPX4 axis, and lipid peroxidation. It is meaningful to deeply explore the relationship between ferroptosis and the male reproductive system, which may provide suggestions regarding pristine therapeutic targets and novel drugs.
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Ferroptose , Masculino , Humanos , Ferroptose/genética , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Morte Celular , Ferro/metabolismo , Peroxidação de LipídeosRESUMO
Human Sertoli cell is required for completing normal spermatogenesis, and significantly, it has important applications in reproduction and regenerative medicine because of its great plasticity. Nevertheless, the molecular mechanisms underlying the fate decisions of human Sertoli cells remain to be clarified. Here, we have demonstrated the expression, function, and mechanism of Homo sapiens-microRNA (hsa-miR)-100-3p in human Sertoli cells. We revealed that miR-100-3p was expressed at a higher level in human Sertoli cells by 10% fetal bovine serum (FBS) than 0.5% FBS. MiR-100-3p mimics enhanced the DNA synthesis and the proliferation of human Sertoli cells, as indicated by 5-ethynyl-2'-deoxyuridine (EdU) and Cell Counting Kit-8 (CCK-8) assays. Flow cytometry showed that miR-100-3p mimics reduced the apoptosis of human Sertoli cells, and notably, we predicted and further identified serum/glucocorticoid regulated kinase family member 3 (SGK3) as a direct target of MiR-100-3p. SGK3 silencing increased the proliferation and decreased the apoptosis of human Sertoli cells, while SGK3 siRNA 3 assumed a similar role to miR-100-3p mimics in human Sertoli cells. Collectively, our study indicates that miR-100-3p regulates the fate decisions of human Sertoli cells by binding to SGK3. This study is of great significance, since it provides the novel epigenetic regulator for the proliferation and apoptosis of human Sertoli cells and it may offer a new clue for gene therapy of male infertility.
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Acute pancreatitis is one of the leading causes of gastrointestinal disorder-related hospitalizations, yet its pathogenesis remains to be fully elucidated. Postsynaptic density protein-95 (PSD-95) is closely associated with tissue inflammation and injury. We aimed to investigate the expression of PSD-95 in pancreatic acinar cells, and its function in regulating the inflammatory response and pancreatic pathological damage in acute pancreatitis. A mouse model of edematous acute pancreatitis was induced with caerulein and lipopolysaccharide in C57BL/6 mice. Tat-N-dimer was injected to inhibit the PSD-95 activity separately, or simultaneously with SB203580, inhibitor of p38 MAPK phosphorylation. Rat pancreatic acinar cells AR42J were cultured with 1 µM caerulein to build a cell model of acute pancreatitis. PSD-95-knockdown and negative control cell lines were constructed by lentiviral transfection of AR42J cells. Paraffin-embedded pancreatic tissue samples were processed for routine HE staining to evaluate the pathological changes of human and mouse pancreatic tissues. Serum amylase and inflammatory cytokine levels were detected with specific ELISA kits. Immunofluorescence, immunohistochemical, Western-blot, and qRT-PCR were used to detect the expression levels of PSD-95, p38, and phosphorylated p38. Our findings showed that PSD-95 is expressed in the pancreatic tissues of humans, C57BL/6 mice, and AR42J cells, primarily in the cytoplasm. PSD-95 expression increased at 2 h, reaching the peak at 6 h in mice and 12 h in AR42J cells. IL-6, IL-8, and TNF-α increased within 2 h of disease induction. The pancreatic histopathologic score was greater in the PSD-95 inhibition group compared with the control (P < 0.05), while it was lesser when phosphorylation of p38 MAPK was inhibited compared with the PSD-95 inhibition group (P < 0.05). Moreover, phosphorylation of p38 MAPK increased statistically after PSD-95 knocked-down. In conclusion, PSD-95 effectively influences the pathological damage of the pancreas in acute pancreatitis by affecting the phosphorylation of p38 MAPK.
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Proteína 4 Homóloga a Disks-Large/metabolismo , Sistema de Sinalização das MAP Quinases , Pancreatite/metabolismo , Células Acinares/metabolismo , Animais , Linhagem Celular , Proteína 4 Homóloga a Disks-Large/genética , Imidazóis/farmacologia , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pâncreas/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Ratos , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
BACKGROUND: Listeriosis is a rare but severe foodborne infectious disease. Perinatal listeriosis is often associated with septicemia, central nervous system (CNS) infection, and serious adverse pregnancy outcomes (miscarriage and neonate death). Here we report the characteristics and outcomes of perinatal listeriosis cases treated over 6 years at Beijing Obstetrics and Gynecology Hospital (BOGH), the largest maternity hospital in China. METHODS: We retrospectively reviewed the records of laboratory-confirmed, pregnancy-associated listeriosis cases treated from January 1, 2013 to December 31, 2018. The clinical manifestations, laboratory results, perinatal complications and outcomes (post-natal follow-up of 6 months) were investigated. RESULTS: In BOGH, 12 perinatal listeriosis cases were diagnosed based on Listeria monocytogenes positive culture, including 10 single pregnancies and 2 twin pregnancies. The corresponding incidence of pregnancy-associated listeriosis was 13.7/100,000 deliveries. Among those cases, four pregnant women and four newborns had septicemia, and two of the neonates with septicemia also suffered CNS infection. All the maternal patients recovered. Two inevitable miscarriages and four fetal stillbirths occurred. Of the eight delivered newborns, six survived, and two died within 2 days from birth. None of the survivors had neurological sequelae during a 6-month follow-up. The overall feto-neonatal fatality rate was 57.1%; notably, this rate was 100% for infections occurring during the second trimester of pregnancy and only 14.3% for those occurring in the third trimester. CONCLUSIONS: Perinatal listeriosis is associated with high feto-neonatal mortality, and thus, a public health concern. Additional large-scale studies are needed to strengthen the epidemiological understanding of listeriosis in China.
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Listeriose/tratamento farmacológico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Aborto Espontâneo/epidemiologia , Adulto , Pequim/epidemiologia , Infecções do Sistema Nervoso Central/microbiologia , Feminino , Maternidades/estatística & dados numéricos , Humanos , Incidência , Recém-Nascido , Listeria monocytogenes/isolamento & purificação , Listeriose/diagnóstico , Listeriose/epidemiologia , Morte Perinatal , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Resultado da Gravidez , Estudos Retrospectivos , Sepse/etiologia , NatimortoRESUMO
Spermatogenesis depends on precise epigenetic and genetic regulation of spermatogonial stem cells (SSCs). However, it remains largely unknown about the roles and mechanisms of small noncoding RNA in regulating the self-renewal and apoptosis of human SSCs. Notably, we have found that Homo sapiens-microRNA (hsa-miR)-1908-3p is expressed at a higher level in human spermatogonia than pachytene spermatocytes. MiR-1908-3p stimulated cell proliferation and DNA synthesis of the human SSC line. Allophycocyanin (APC) Annexin V and propidium iodide staining, determined by flow cytometric analysis and TUNEL assays, showed that miR-1908-3p inhibited early and late apoptosis of the human SSC line. Furthermore, Kruppel-like factor 2 (KLF2) was predicted and verified as the target of miR-1908-3p, and, significantly, KLF2 silencing resulted in the increase of proliferation and DNA synthesis, as well as reduction of apoptosis of the human SSC line. Moreover, KLF2 silencing ameliorated the decrease in the proliferation and DNA synthesis and the enhancement in the apoptosis of the human SSC line caused by miR-1908-3p inhibition. Collectively, these results implicate that miR-1908-3p stimulates the self-renewal and suppresses the apoptosis of human SSCs by targeting KLF2. This study thus provides a novel epigenetic regulatory mechanism underlying the fate determinations of human SSCs, and it offers new endogenous targets for treating male infertility.
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BACKGROUND AND OBJECTIVES: Osteoarthritis (OA) is a widespread degenerative joint disease characterized by articular cartilage degradation and is the leading cause of physical disability. Noncoding RNAs, especially long noncoding RNAs (lncRNAs) and microRNAs, are involved in the degradation of the chondrocyte extracellular matrix (ECM) in patients with OA. The present study was aimed to investigate the effects of lncRNA and miR-22 on the degradation of the chondrocyte ECM and underlying mechanisms. METHODS: To simulate conditions found in OA, primary cultured chondrocytes were treated with IL-1, TGF-ß, or sb525334. Real-time PCR and Western blot analysis were performed to detect expressions of miR-22, lncRNA-TM1P3, ALK1, MMP13, pSMAD1/5, SMAD1, and pSMAD5. Small interfering RNAs and a miR-22 mimic or inhibitor were utilized to determine lncRNA-TM1P3 knockdown and miR-22 overexpression or inhibition. RESULTS: The lncRNA-TM1P3 significantly upregulated in patients with OA, accompanied by the downregulation of miR-22 and upregulation of pSMAD1/5 and MMP13, which ultimately resulted in the degradation of the chondrocyte ECM in patients with OA. Bioinformatics analysis predicted miR-22 as a target of both lncRNA-TM1P3 and MMP13. The lncRNA-TM1P3 knockdown significantly increased the expression of ALK1, a corresponding increase in ECM degradation was observed by affecting the phosphorylation of SMAD1/5 and the expression of MMP13, which did not affect the expression of ALK1. CONCLUSIONS: These findings demonstrated that the lncRNA-TM1P3/miR-22/TGF-ß signaling/MMP13 axis is involved in the degradation of chondrocyte ECM in patients with OA, which could provide novel therapies for OA treatment.
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Receptores de Activinas Tipo II/genética , Condrócitos/citologia , Matriz Extracelular/metabolismo , MicroRNAs/genética , Osteoartrite/genética , RNA Longo não Codificante/genética , Receptores de Activinas Tipo II/metabolismo , Adulto , Estudos de Casos e Controles , Células Cultivadas , Condrócitos/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Metaloproteinase 13 da Matriz/metabolismo , Pessoa de Meia-Idade , Osteoartrite/metabolismo , Transdução de Sinais , Proteína Smad1/metabolismo , Proteína Smad5/metabolismo , Regulação para CimaRESUMO
The aim of the present study was to investigate the protective effect of eugenol on the transplanted heart and explore its mechanisms of action. Male Sprague-Dawley rats were randomly divided into a sham group (n=10), a eugenol group (n=10 pairs, donors and recipients) and a control group (n=10 pairs, donors and recipients). The recipients in the eugenol group received an intraperitoneal injection of eugenol (20 mg/kg/day). The sham group and the control group received equal volumes of physiological saline by intraperitoneal injection. After 15 days the recipients in the control and eugenol groups underwent abdominal heterotopic heart transplantation, while the sham group received only a coeliotomy. The orthotopic hearts in the sham group and the heterotopic hearts in the eugenol and control groups, as well as the peripheral blood samples from all three groups were taken 3 h post operation for biochemical, histopathological, molecular and apoptosis analyses. Compared with the control group, the eugenol treatment significantly reduced the myocardial malondialdehyde content, serum cardiac troponin I, creatine kinase-MB, tumor necresis factor-α and interleukin-6 levels (P<0.05) and significantly alleviated myocardial injury. Western blot analysis demonstrated that the protein expression of cleaved Poly (ADP-ribose) polymerase 1, BAX and active caspase-3 in the eugenol group were significantly decreased, while B-cell lymphoma 2 expression was significantly increased compared with the control group (P<0.05). The myocardial apoptosis rate of the eugenol group was significantly decreased compared with the control group (P<0.05). In conclusion eugenol treatment significantly reduced myocardial injury and demonstrated protective effects for the transplanted heart.
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OBJECTIVES: The aim of this study was to investigate the effects of emodin on attenuating autophagy response in acute pancreatitis (AP) models. METHODS: Acute pancreatitis was induced in Wistar rats by injecting 3% sodium taurocholate into the biliopancreatic duct. Emodin (40 mg/kg per day) was then given intragastrically, administrated 2 hours after AP induction. Rats were killed 24 hours after AP induction. The pancreatic injury was assessed using biochemical and histological approaches. Autophagosomes in pancreatic acinar cells were observed by electron microscopy. The expression levels of microtubule-associated protein 1 light chain 3 (LC3) B/A, beclin-1, and p62/SQSTM1 (p62) were detected by Western blotting, quantitative real-time polymerase chain reaction, and immunohistochemistry in pancreatic tissues. RESULTS: Compared with non-emodin-treated rats, the pathological injuries of the pancreas of emodin-treated rats were significantly alleviated, and autophagy vacuole formation was reduced within pancreatic acinar cells. Administration of emodin led to a reduction in the autophagy-associated protein level of LC3 (B/A) and p62 but not beclin-1. The transcript levels of LC3B, beclin-1, and p62 were decreased in the emodin-treated rats compared with non-emodin-treated rats. CONCLUSIONS: Our data demonstrate that emodin plays a critical role in ameliorating AP, possibly by down-regulating autophagic protein levels.
Assuntos
Autofagia/efeitos dos fármacos , Emodina/farmacologia , Pâncreas/efeitos dos fármacos , Pancreatite/prevenção & controle , Doença Aguda , Animais , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Expressão Gênica/efeitos dos fármacos , Masculino , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Pâncreas/metabolismo , Pâncreas/patologia , Pancreatite/induzido quimicamente , Pancreatite/genética , Substâncias Protetoras/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Ratos Wistar , Proteína Sequestossoma-1/genética , Proteína Sequestossoma-1/metabolismo , Ácido TaurocólicoRESUMO
Coxsackievirus B3 (CVB3) infection has been shown to stimulate autophagy. We have demonstrated that the inhibition of phosphoinositide 3kinase (PI3K)/protein kinase B/mammalian target of rapamycin complex (mTORC) signaling pathway could affect the autophagic reaction induced by CVB3 infection in our previous study. However, the processes associating autophagy and CVB3 replication remain to be determined. In the present study, CVB3induced autophagy and its impact on viral replication were investigated. Rapamycin (inhibitor of mTOR) and ZSTK474 (inhibitor of PI3K) were used to change the autophagic reaction caused by CVB3 in Hela cells at different postinfection (p.i.) time points (6, 9, 12 and 24 h p.i.), meanwhile, we detected the CVB3 mRNA replication and CVB3 capsid protein VP1 expression following the change of autophagy. Here, it was showed that ZSTK474 and Rapamycin promoted CVB3induced autophagy, as well as decreasing CVB3 mRNA replication and CVB3 capsid protein VP1 expression at 6 and 9 h p.i. ZSTK474 also alleviated CVB3induced autophagy, and decreased CVB3 mRNA replication and VP1 expression at 12 and 24 h p.i. However, Rapamycin continued to promote CVB3induced autophagy and increase CVB3 mRNA replication at 12 and 24 h p.i, as well as increase VP1 expression at 12 h, but not at 24 h, p.i. In the present study, we found Rapamycin and ZSTK474 have differential effects at different p.i. timepoints regarding CVB3 replication and CVB3induced autophagy. This indicates that the association between CVB3induced autophagy and viral replication depends on the infection time. During the early course of infection, autophagy may help host cells clear the virus, thereby providing protection, whereas when the infection time increases, autophagy may be exploited for viral replication.
Assuntos
Autofagia/efeitos dos fármacos , Enterovirus Humano B/fisiologia , Sirolimo/farmacologia , Triazinas/farmacologia , Replicação Viral/efeitos dos fármacos , Células HeLa , HumanosRESUMO
Gefitinib has been widely used in the first-line treatment of advanced EGFR-mutated non-small-cell lung cancer (NSCLC). However, many NSCLC patients will acquire resistance to gefitinib after 9-14 months of treatment. This study revealed that Krüppel-like factor 4 (KLF4) contributes to the formation of gefitinib resistance in c-Met-overexpressing NSCLC cells. We observed that KLF4 was overexpressed in c-Met-overexpressing NSCLC cells and tissues. Knockdown of KLF4 increased tumorigenic properties in gefitinib-resistant NSCLC cell lines without c-Met overexpression, but it reduced tumorigenic properties and increased gefitinib sensitivity in gefitinib-resistant NSCLC cells with c-Met overexpression, whereas overexpression of KLF4 reduced gefitinib sensitivity in gefitinib-sensitive NSCLC cells. Furthermore, Western blot analysis revealed that KLF4 contributed to the formation of gefitinib resistance in c-Met-overexpressing NSCLC cells by inhibiting the expression of apoptosis-related proteins under gefitinib treatment and activating the c-Met/Akt signaling pathway by decreasing the inhibition of ß-catenin on phosphorylation of c-Met to prevent blockade by gefitinib. In summary, this study's results suggest that KLF4 is a promising candidate molecular target for both prevention and therapy of NSCLC with c-Met overexpression.