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BACKGROUND: Chinese Cymbidium orchids, cherished for their deep-rooted cultural significance and significant economic value in China, have spawned a rich tapestry of cultivars. However, these orchid cultivars are facing challenges from insufficient cultivation practices and antiquated techniques, including cultivar misclassification, complex identification, and the proliferation of counterfeit products. Current commercial techniques and academic research primarily emphasize species identification of orchids, rather than delving into that of orchid cultivars within species. RESULTS: To bridge this gap, the authors dedicated over a year to collecting a cultivar image dataset for Chinese Cymbidium orchids named Orchid2024. This dataset contains over 150,000 images spanning 1,275 different categories, involving visits to 20 cities across 12 provincial administrative regions in China to gather pertinent data. Subsequently, we introduced various visual parameter-efficient fine-tuning (PEFT) methods to expedite model development, achieving the highest top-1 accuracy of 86.14% and top-5 accuracy of 95.44%. CONCLUSION: Experimental results demonstrate the complexity of the dataset while highlighting the considerable promise of PEFT methods within flower image classification. We believe that our work not only provides a practical tool for orchid researchers, growers and market participants, but also provides a unique and valuable resource for further exploring fine-grained image classification tasks. The dataset and code are available at https://github.com/pengyingshu/Orchid2024 .
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Premature ovarian insufficiency (POI) is one of the important causes of female infertility. Yet the aetiology for POI is still elusive. FBXW7 (F-box with 7 tandem WD) is one of the important components of the Skp1-Cullin1-F-box (SCF) E3 ubiquitin ligase. FBXW7 can regulate cell growth, survival and pluripotency through mediating ubiquitylation and degradation of target proteins via triggering the ubiquitin-proteasome system, and is associated with tumorigenesis, haematopoiesis and testis development. However, evidence establishing the function of FBXW7 in ovary is still lacking. Here, we showed that FBXW7 protein level was significantly decreased in the ovaries of the cisplatin-induced POI mouse model. We further showed that mice with oocyte-specific deletion of Fbxw7 demonstrated POI, characterized with folliculogenic defects, early depletion of follicle reserve, disordered hormonal secretion, ovarian dysfunction and female infertility. Impaired oocyte-GCs communication, manifested as down-regulation of connexin 37, may contribute to follicular development failure in the Fbxw7-mutant mice. Furthermore, single-cell RNA sequencing and in situ hybridization results indicated an accumulation of Clu and Ccl2 transcripts, which may alter follicle microenvironment deleterious to oocyte development and accelerate POI. Our results establish the important role of Fbxw7 in folliculogenesis and ovarian function, and might provide valuable information for understanding POI and female infertility.
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Proteína 7 com Repetições F-Box-WD , Oócitos , Folículo Ovariano , Insuficiência Ovariana Primária , Animais , Feminino , Insuficiência Ovariana Primária/genética , Insuficiência Ovariana Primária/metabolismo , Insuficiência Ovariana Primária/patologia , Proteína 7 com Repetições F-Box-WD/metabolismo , Proteína 7 com Repetições F-Box-WD/genética , Oócitos/metabolismo , Camundongos , Folículo Ovariano/metabolismo , Folículo Ovariano/crescimento & desenvolvimento , Folículo Ovariano/patologia , Modelos Animais de Doenças , Deleção de Genes , Camundongos Knockout , Infertilidade Feminina/genética , Infertilidade Feminina/metabolismo , Infertilidade Feminina/patologia , Cisplatino/efeitos adversosRESUMO
Obesity is one of the most common metabolic diseases around the world, which is distinguished by the abnormal buildup of triglycerides within adipose cells. Recent research has revealed that autophagy regulates lipid mobilization to maintain energy balance. TIGAR (Trp53 induced glycolysis regulatory phosphatase) has been identified as a glycolysis inhibitor, whether it plays a role in the metabolism of lipids is unknown. Here, we found that TIGAR transgenic (TIGAR+/+) mice exhibited increased fat mass and trended to obesity phenotype. Non-target metabolomics showed that TIGAR caused the dysregulation of the metabolism profile. The quantitative transcriptome sequencing identified an increased levels of LRRK2 and RAB7B in the adipose tissue of TIGAR+/+ mice. It was confirmed in vitro that TIGAR overexpression increased the levels of LRRK2 by inhibiting polyubiquitination degradation, thereby suppressing macroautophagy and chaperone-mediated autophagy (CMA) while increasing lipid accumulation which were reversed by the LRRK2 inhibitor DNL201. Furthermore, TIGAR drove LRRK2 to interact with RAB7B for suppressing lysosomal degradation of lipid droplets, while the increased lipid droplets in adipocytes were blocked by the RAB7B inhibitor ML282. Additionally, fat-specific TIGAR knockdown of TIGAR+/+ mice alleviated the symptoms of obesity, and adipose tissues-targeting superiority DNL201 nano-emulsion counteracted the obesity phenotype in TIGAR+/+ mice. In summary, the current results indicated that TIGAR performed a vital function in the lipid metabolism through LRRK2-mediated negative regulation of macroautophagy and CMA in adipocyte. The findings suggest that TIGAR has the potential to serve as a viable therapeutic target for treating obesity and its associated metabolic dysfunction.
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Adipócitos , Autofagia , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Obesidade , Monoéster Fosfórico Hidrolases , Proteínas rab de Ligação ao GTP , proteínas de unión al GTP Rab7 , Animais , Obesidade/metabolismo , Obesidade/patologia , Autofagia/fisiologia , Adipócitos/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas rab de Ligação ao GTP/genética , Camundongos , proteínas de unión al GTP Rab7/metabolismo , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Monoéster Fosfórico Hidrolases/metabolismo , Monoéster Fosfórico Hidrolases/genética , Camundongos Transgênicos , Chaperonas Moleculares/metabolismo , Camundongos Endogâmicos C57BL , Humanos , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos/genética , Ubiquitinação , Masculino , Proteínas Reguladoras de ApoptoseRESUMO
Sunitinib, the first-line targeted therapy for metastatic clear cell renal cell carcinoma (ccRCC), faces a significant challenge as most patients develop acquired resistance. Integrated genomic and proteomic analyses identified PYGL as a novel therapeutic target for ccRCC. PYGL knockdown inhibited cell proliferation, cloning capacity, migration, invasion, and tumorigenesis in ccRCC cell lines. PYGL expression was increased in sunitinib-resistant ccRCC cell lines, and CP-91149 targeting the PYGL could restore drug sensitivity in these cell lines. Moreover, chromatin immune-precipitation assays revealed that PYGL upregulation is induced by the transcription factor, hypoxia-inducible factor 1α. Overall, PYGL was identified as a novel diagnostic biomarker by combining genomic and proteomic approaches in ccRCC, and sunitinib resistance to ccRCC may be overcome by targeting PYGL.
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Feline interferon omega (IFN-ω) has been proven to have high antiviral activity; however, its in-depth antiviral effects remain unknown. Extracellular vesicles (EVs) have been demonstrated to participate in the regulation of the immune response pathway for the body through various active substances, especially through the microRNA (miRNA) carried by them. In this study, we isolated EVs from feline peripheral blood by differential centrifugation, and further found that the content of IFN-ω in EVs increased continuously within 24 h after IFN-ω treatment, and a large number of miRNAs were significantly downregulated in EVs within 12 h after IFN-ω treatment. These significantly differentially expressed miRNAs were important for regulating changes in antiviral cytokines. This study reveals for the first time the correlation between EVs-mediated miRNA in feline peripheral blood and IFN-ω on antiviral immune response, which may provide strong data support for the development of novel antiviral nanomedicine and the research of the antiviral effects of IFN-ω.
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Vesículas Extracelulares , Interferon Tipo I , MicroRNAs , Gatos , Animais , MicroRNAs/genética , Citocinas , Vesículas Extracelulares/metabolismoRESUMO
Few studies have focused on the evaluation of vaccine effectiveness (VE) in mainland China. This study was to characterize the VE including the frequent symptoms, laboratory indices, along with endotracheal intubation, hospital length of stay (LoS), and survival status. This retrospective cohort study included patients with COVID-19 admitted to our hospital. Statistical comparisons of continuous variables were carried out with an independent Student's t-test or Mann-Whitney U test. For categorical variables, the Chi-square test and Fisher exact test were used. Multivariable regression analysis was performed to adjust the confounding factors such as age, gender, body mass index (BMI), residential area, smoking status, the Charlson comorbidity index (CCI) score, followed by investigating the effects of vaccination on critical ill prevention, reduced mortality and endotracheal intubation, LoS and inspired oxygen. This study included 549 hospitalized patients with COVID-19, including 222 (40.43 %) vaccinated participants and 327 (59.57 %) unvaccinated counterparts. There was no obvious difference between the two groups in typical clinical symptoms of COVID-19, clinical laboratory results and mortality. Multivariable analysis showed that COVID-19 vaccine obviously reduced LoS by 1.2 days (lnLoS = -0.14, 95 %CI[-0.24,-0.04]; P = 0.005) and decreased fraction of inspired oxygen by 40 % (OR: 0.60; 95 %CI[0.40,0.90]; P = 0.013) after adjusting age, gender, BMI, residential area, smoking status and CCI score. In contrast, vaccination induced reduction in the critically ill, mortality, and endotracheal intubation compared with the unvaccinated counterparts, but with no statistical differences. Vaccinated patients hospitalized with COVID-19 have a reduced LoS and fraction of inspired oxygen compared to unvaccinated cases in China.
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Multiple infections are a key component of HPV pathogenesis and have a direct impact on how an infection turns out. It's crucial to look at the associations between HPV multiple infections and both age and HPV genotypes in the Chinese population, searching for the causative factors of multiple infections with a view to providing new ideas for the treatment and prevention of multiple infections. In this study, we retrospectively analyzed the data of HPV infections among outpatients from the 2019 year to the 2021 year of Shandong Maternal and Child Health Hospital. Analyzed the correlation between HPV multiple infections and age using logistic regression. Differences in the percentage of multiple infections between age groups were compared using the chi-square test. The chi-square test compared the differences in the distribution of 15 common HPV genotypes in mono- versus multiple infections. A two-dimensional matrix presented the frequency of HPV genotype combinations. Logistics regression analysis showed that age was significantly associated with the occurrence of multiple infections, with a dominance ratio OR 1.026 (95% CI 1.02-1.04). Interestingly, the proportion of HPV multiple infections among HPV-positive individuals increases with age in people older than 30 years of age. The chi-square test showed there was a difference in the distribution of HPV genotypes between multiple infections and mono- HPV infection (χ2 = 76.4; p = 0.000), a difference in the composition of HPV genotypes for dual versus single infections (χ2 = 90.6; p = 0.000) and a difference in HPV genotypes for triple versus single infections (χ2 = 56.7; p = 0.000). A 2 × 2 matrix showed that the combination of HPV52/HPV58 (30; 6.4%) was the combination of the highest frequency of infection for dual infections; The HPV52/HPV58 (21; 4.8%) combination was the highest frequency of HPV triple infection combination. HPV multiple infections were positively correlated with age; increasing age was positively correlated with the proportion of HPV multiple infections in the total infected population; the distribution of the 15 common genotypes of HPV differed between multiple infections and single infections; and HPV52:58 was a common type of infection combination in the Shandong population.
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Alphapapillomavirus , Papillomavirus Humano , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Criança , Humanos , Adulto , Estudos Retrospectivos , Prevalência , Papillomaviridae/genética , Genótipo , China/epidemiologiaRESUMO
BACKGROUND: The importance of mitochondria in normal heart function are well recognized and recent studies have implicated changes in mitochondrial metabolism with some forms of heart disease. Previous studies demonstrated that knockdown of the mitochondrial ribosomal protein S5 (MRPS5) by small interfering RNA (siRNA) inhibits mitochondrial translation and thereby causes a mitonuclear protein imbalance. Therefore, we decided to examine the effects of MRPS5 loss and the role of these processes on cardiomyocyte proliferation. METHODS: We deleted a single allele of MRPS5 in mice and used left anterior descending coronary artery ligation surgery to induce myocardial damage in these animals. We examined cardiomyocyte proliferation and cardiac regeneration both in vivo and in vitro. Doxycycline treatment was used to inhibit protein translation. Heart function in mice was assessed by echocardiography. Quantitative real-time polymerase chain reaction and RNA sequencing were used to assess changes in transcription and chromatin immunoprecipitation (ChIP) and BioChIP were used to assess chromatin effects. Protein levels were assessed by Western blotting and cell proliferation or death by histology and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assays. Adeno-associated virus was used to overexpress genes. The luciferase reporter assay was used to assess promoter activity. Mitochondrial oxygen consumption rate, ATP levels, and reactive oxygen species were also analyzed. RESULTS: We determined that deletion of a single allele of MRPS5 in mice results in elevated cardiomyocyte proliferation and cardiac regeneration; this observation correlates with improved cardiac function after induction of myocardial infarction. We identified ATF4 (activating transcription factor 4) as a key regulator of the mitochondrial stress response in cardiomyocytes from Mrps5+/- mice; furthermore, ATF4 regulates Knl1 (kinetochore scaffold 1) leading to an increase in cytokinesis during cardiomyocyte proliferation. The increased cardiomyocyte proliferation observed in Mrps5+/- mice was attenuated when one allele of Atf4 was deleted genetically (Mrps5+/-/Atf4+/-), resulting in the loss in the capacity for cardiac regeneration. Either MRPS5 inhibition (or as we also demonstrate, doxycycline treatment) activate a conserved regulatory mechanism that increases the proliferation of human induced pluripotent stem cell-derived cardiomyocytes. CONCLUSIONS: These data highlight a critical role for MRPS5/ATF4 in cardiomyocytes and an exciting new avenue of study for therapies to treat myocardial injury.
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Células-Tronco Pluripotentes Induzidas , Miócitos Cardíacos , Humanos , Camundongos , Animais , Miócitos Cardíacos/metabolismo , Doxiciclina , Células Cultivadas , Células-Tronco Pluripotentes Induzidas/metabolismo , RNA Interferente Pequeno/metabolismo , Biossíntese de Proteínas , Proliferação de Células , Regeneração , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismoRESUMO
The previous research has found that human papillomavirus (HPV) infection is the main cause of cervical cancer, but it is still unclear whether HPV infection, as well as the HPV genotypes, are related to reproductive tract infections in the Chinese population. Patients who underwent HPV screening at Shandong Maternal and Child Health Hospital were selected, and the HPV infection status was analyzed among patients with cervical lesions, bacterial vaginosis, cervical inflammation, fungal vaginitis, and pelvic infections. SPSS 22 statistical analysis was used to analyze the differences in HPV infection types and rates between the control group and the experimental group. The HPV infection rate of bacterial vaginosis (χ2 = 13.4; P < .001) and fungal vaginitis (χ2 = 3.3; P < .045) are both significantly different from the control group. The single HPV infections reveals significant differences from control group in bacterial vaginosis (χ2 = 7.3; P = .004), fungal vaginitis (χ2 = 4.5; P = .023), and cervical lesions (χ2 = 58.8; P < .001). In the bacterial infection group, HPV51 (1.9%; χ2 = 6.0; P = .008) and HPV58 (4.7%; χ2 = 3.3; P = .044) showed significant differences in infection compared to the control group. In the fungal infection group, HPV39 (2.7%; χ2 = 4.7; P = .032) showed a significant difference in infection compared to the control group. Cervical lesions, bacterial vaginosis, fungal vaginitis, and cervical lesions among Chinese population exhibit age-specified distribution. HPV infection rate in bacterial vaginitis, fungal vaginitis and cervical lesions was higher than that in normal group. HPV52 and HPV16 infection are different, and HPV39 is different between bacterial vaginitis and fungal vaginitis.
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Papillomaviridae , Infecções por Papillomavirus , Infecções do Sistema Genital , Feminino , Humanos , China/epidemiologia , População do Leste Asiático/estatística & dados numéricos , Genótipo , Papillomaviridae/genética , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Prevalência , Infecções do Sistema Genital/epidemiologia , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/virologia , Vaginite/epidemiologia , Vaginose Bacteriana/epidemiologiaRESUMO
Impaired wound healing and ulcer complications are major causes of morbidity in patients with diabetes. Impaired wound healing is associated with increased inflammation and poor angiogenesis in diabetes patients. Here, we demonstrate that topical administration of a secreted recombinant protein (Meteorin-like [Metrnl]) accelerates wound epithelialization and angiogenesis in mice. We observed a significant increase in Metrnl expression during physiological wound healing; however, its expression remained low during diabetic wound healing. Functionally, the recombinant protein Metrnl significantly accelerated wound closure in normal and diabetic mice models including db/db, high-fat diet/streptozotocin (HFD/STZ), and STZ mice. Mechanistically, keratinocytes secrete quantities of Metrnl to promote angiogenesis; increase endothelial cell proliferation, migration, and tube formation; and enhance macrophage polarization to the M2 type. Meanwhile, M2 macrophages secrete Metrnl to further stimulate angiogenesis. Moreover, the keratinocyte- and macrophage-produced cytokine Metrnl drives postinjury angiogenesis and reepithelialization through activation of AKT phosphorylation (S473) in a KIT receptor tyrosine kinase (c-Kit)-dependent manner. In conclusion, our study suggests that Metrnl has a biological effect in accelerating wound closure through c-Kit-dependent angiogenesis and epithelialization.
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The fidelity of alternative splicing (AS) patterns is essential for growth development and cell fate determination. However, the scope of the molecular switches that regulate AS remains largely unexplored. Here we show that MEN1 is a previously unknown splicing regulatory factor. MEN1 deletion resulted in reprogramming of AS patterns in mouse lung tissue and human lung cancer cells, suggesting that MEN1 has a general function in regulating alternative precursor mRNA splicing. MEN1 altered exon skipping and the abundance of mRNA splicing isoforms of certain genes with suboptimal splice sites. Chromatin immunoprecipitation and chromosome walking assays revealed that MEN1 favored the accumulation of RNA polymerase II (Pol II) in regions encoding variant exons. Our data suggest that MEN1 regulates AS by slowing the Pol II elongation rate and that defects in these processes trigger R-loop formation, DNA damage accumulation and genome instability. Furthermore, we identified 28 MEN1-regulated exon-skipping events in lung cancer cells that were closely correlated with survival in patients with lung adenocarcinoma, and MEN1 deficiency sensitized lung cancer cells to splicing inhibitors. Collectively, these findings led to the identification of a novel biological role for menin in maintaining AS homeostasis and link this role to the regulation of cancer cell behavior.
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Processamento Alternativo , Neoplasias Pulmonares , Animais , Humanos , Camundongos , Processamento Alternativo/genética , Instabilidade Genômica/genética , Neoplasias Pulmonares/genética , Estruturas R-Loop , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , RNA Mensageiro/metabolismoRESUMO
Rab26 is known to regulate multiple membrane trafficking events, but its role in insulin secretion in pancreatic ß cells remains unclear despite it was first identified in the pancreas. In this study, we generated Rab26-/- mice through CRISPR/Cas9 technique. Surprisingly, insulin levels in the blood of the Rab26-/- mice do not decrease upon glucose stimulation but conversely increase. Deficiency of Rab26 promotes insulin secretion, which was independently verified by Rab26 knockdown in pancreatic insulinoma cells. Conversely, overexpression of Rab26 suppresses insulin secretion in both insulinoma cell lines and isolated mouse islets. Islets overexpressing Rab26, upon transplantation, also failed to restore glucose homeostasis in type 1 diabetic mice. Immunofluorescence microscopy revealed that overexpression of Rab26 results in clustering of insulin granules. GST-pulldown experiments reveal that Rab26 interacts with synaptotagmin-1 (Syt1) through directly binding to its C2A domain, which interfering with the interaction between Syt1 and SNAP25, and consequently inhibiting the exocytosis of newcomer insulin granules revealed by TIRF microscopy. Our results suggest that Rab26 serves as a negative regulator of insulin secretion, via suppressing insulin granule fusion with plasma membrane through sequestering Syt1.
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Diabetes Mellitus Experimental , Células Secretoras de Insulina , Insulinoma , Ilhotas Pancreáticas , Neoplasias Pancreáticas , Animais , Camundongos , Diabetes Mellitus Experimental/metabolismo , Exocitose/fisiologia , Glucose/metabolismo , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Insulinoma/metabolismo , Ilhotas Pancreáticas/metabolismo , Neoplasias Pancreáticas/metabolismoRESUMO
The low-density lipoprotein (LDL) is a major cholesterol carrier in circulation and is internalized into cells through LDL receptor (LDLR)-mediated endocytosis. The LDLR protein is highly expressed in the steroidogenic organs and LDL cholesterol is an important source for steroidogenesis. Cholesterol must be transported into the mitochondria, where steroid hormone biosynthesis initiates. However, how LDL cholesterol is conveyed to the mitochondria is poorly defined. Here, through genome-wide small hairpin RNA screening, we find that the outer mitochondrial membrane protein phospholipase D6 (PLD6), which hydrolyses cardiolipin to phosphatidic acid, accelerates LDLR degradation. PLD6 promotes the entrance of LDL and LDLR into the mitochondria, where LDLR is degraded by mitochondrial proteases and LDL-carried cholesterol is used for steroid hormone biosynthesis. Mechanistically, the outer mitochondrial membrane protein CISD2 binds to the cytosolic tail of LDLR and tethers LDLR+ vesicles to the mitochondria. The fusogenic lipid phosphatidic acid generated by PLD6 facilitates the membrane fusion of LDLR+ vesicles with the mitochondria. This intracellular transport pathway of LDL-LDLR bypasses the lysosomes and delivers cholesterol to the mitochondria for steroidogenesis.
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Colesterol , Mitocôndrias , LDL-Colesterol , Colesterol/metabolismo , Mitocôndrias/metabolismo , Proteínas de Membrana/metabolismo , HormôniosRESUMO
BACKGROUND: Lower plasma levels of LDL (low-density lipoprotein) cholesterol (LDL-C) can reduce the risk of atherosclerotic cardiovascular disease. The loss-of-function mutations in PCSK9 (proprotein convertase subtilisin/kexin type 9) have been known to associate with low LDL-C in many human populations. PCSK9 genetic variants in Chinese Uyghurs who are at high risk of atherosclerotic cardiovascular disease due to their dietary habits have not been reported. METHODS: The study involved the whole-exome and target sequencing of college students from Uyghur and other ethnic groups in Xinjiang, China, for the association of PCSK9 loss-of-function mutations with low plasma levels of LDL-C. The mechanisms by which the identified mutations affect the function of PCSK9 were investigated in cultured cells using biochemical and cell assays. The causal effects of the identified PCSK9 mutations on LDL-C levels were verified in mice injected with adeno-associated virus expressing different forms of PCSK9 and fed a high-cholesterol diet. RESULTS: We identified 2 PCSK9 mutations-E144K and C378W-in Chinese Uyghurs with low plasma levels of LDL-C. The E144K and C378W mutations impaired the maturation and secretion of the PCSK9 protein, respectively. Adeno-associated virus-mediated expression of E144K and C378W mutants in Pcsk9 KO (knockout) mice fed a high-cholesterol diet also hampered PCSK9 secretion into the serum, resulting in elevated levels of LDL receptor in the liver and reduced levels of LDL-C in the serum. CONCLUSIONS: Our study shows that E144K and C378W are PCSK9 loss-of-function mutations causing low LDL-C levels in mice and probably in humans as well.
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Aterosclerose , Doenças Cardiovasculares , Hipercolesterolemia , Humanos , Camundongos , Animais , Pró-Proteína Convertase 9/genética , LDL-Colesterol , Serina Endopeptidases/genética , Pró-Proteína Convertases/genética , Pró-Proteína Convertases/metabolismo , Receptores de LDL/genética , Receptores de LDL/metabolismo , Camundongos Knockout , Aterosclerose/genética , Aterosclerose/prevenção & controle , Aterosclerose/metabolismo , MutaçãoRESUMO
The regulation of the informational flow from the mitochondria to the nucleus (mitonuclear communication) is not fully characterized in the heart. We have determined that mitochondrial ribosomal protein S5 (MRPS5/uS5m) can regulate cardiac function and key pathways to coordinate this process during cardiac stress. We demonstrate that loss of Mrps5 in the developing heart leads to cardiac defects and embryonic lethality while postnatal loss induces cardiac hypertrophy and heart failure. The structure and function of mitochondria is disrupted in Mrps5 mutant cardiomyocytes, impairing mitochondrial protein translation and OXPHOS. We identify Klf15 as a Mrps5 downstream target and demonstrate that exogenous Klf15 is able to rescue the overt defects and re-balance the cardiac metabolome. We further show that Mrps5 represses Klf15 expression through c-myc, together with the metabolite L-phenylalanine. This critical role for Mrps5 in cardiac metabolism and mitonuclear communication highlights its potential as a target for heart failure therapies.
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Insuficiência Cardíaca , Biossíntese de Proteínas , Humanos , Cardiomegalia/genética , Cardiomegalia/metabolismo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismoRESUMO
Diabetic kidney disease (DKD) is one of the most serious complications of diabetes mellitus (DM) and the main cause of end-stage renal failure. However, the pathogenesis of DKD is complicated. In this study, we found that miR-124-3p plays a key role in regulating renal mitochondrial function and explored its possible mechanism in DKD progression by performing a series of in vitro and in vivo experiments. Decreased expression of miR-124-3p was found in db/db mice compared to db/m mice. Moreover, miR-124-3p down-regulated FOXQ1 by targeting FOXQ1 mRNA 3'-UTR in NRK-52E cells. Also, an increase in FOXQ1 and down-regulation of Sirt4 were found in db/db mouse kidney and renal tubular epithelial cells cultured with high glucose and high lipid. Overexpression of FOXQ1 could further down-regulate the expression of Sirt4 and aggravate the damage of mitochondria. Conversely, the knockdown of the FOXQ1 gene induced Sirt4 expression and partially restored mitochondrial function. To verify the effects of miR-124-3p on Sirt4 and mitochondria, we found that miR-124-3p mimics could up-regulate Sirt4 and inhibit ROS production and MitoSOX, thus restoring the number and morphology of mitochondria. These results showed that under high-glucose and high-lipid conditions, the down-regulation of miR-124-3p induces FOXQ1 in renal tubular epithelial cells, which in turn suppresses Sirt4 and leads to mitochondrial dysfunction, promoting the development of DKD.
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Nefropatias Diabéticas , MicroRNAs , Camundongos , Animais , MicroRNAs/metabolismo , Células Epiteliais/metabolismo , Nefropatias Diabéticas/metabolismo , Camundongos Endogâmicos , Glucose/metabolismo , Mitocôndrias/metabolismo , Lipídeos/farmacologiaRESUMO
Ectopic lipid accumulation in renal tubules is closely related to the pathogenesis of diabetic kidney disease (DKD), and mitochondrial dysfunction is thought to play a key role in lipid accumulation. Therefore, maintaining mitochondrial homeostasis holds considerable promise as a therapeutic strategy for the treatment of DKD. Here, we report that the Meteorin-like (Metrnl) gene product mediates lipid accumulation in the kidney and has therapeutic potential for DKD. We confirmed the reduced expression of Metrnl in renal tubules, which was inversely correlated with DKD pathological changes in human patients and mouse models. Functionally, pharmacological administration of recombinant Metrnl (rMetrnl) or Metrnl overexpression could alleviate lipid accumulation and inhibit kidney failure. In vitro, rMetrnl or Metrnl overexpression attenuated palmitic acid-induced mitochondrial dysfunction and lipid accumulation in renal tubules accompanied by maintained mitochondrial homeostasis and enhanced lipid consumption. Conversely, shRNA-mediated Metrnl knockdown diminished the protective effect on the kidney. Mechanistically, these beneficial effects of Metrnl were mediated by the Sirt3-AMPK signaling axis to maintain mitochondrial homeostasis and through Sirt3-uncoupling protein-1 to promote thermogenesis, consequently alleviating lipid accumulation. In conclusion, our study demonstrates that Metrnl regulated lipid metabolism in the kidney by modulating mitochondrial function and is a stress-responsive regulator of kidney pathophysiology, which sheds light on novel strategies for treating DKD and associated kidney diseases. ARTICLE HIGHLIGHTS: Metrnl is expressed in renal tubules and is reduced under diabetic conditions. The concentration of Metrnl in the kidney is correlated with lipid accumulation and serum creatinine. Metrnl-specific overexpression in the kidney or recombinant Metrnl administration alleviates renal injuries in diabetic mice. Metrnl regulates renal tubules lipid metabolism through Sirt3-AMPK/UCP1 signaling axis-mediated mitochondrial homeostasis.
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Diabetes Mellitus Experimental , Nefropatias Diabéticas , Sirtuína 3 , Humanos , Camundongos , Animais , Nefropatias Diabéticas/metabolismo , Diabetes Mellitus Experimental/metabolismo , Sirtuína 3/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Mitocôndrias/metabolismo , Lipídeos , HomeostaseRESUMO
Impaired protein N-glycosylation leads to the endoplasmic reticulum (ER) stress, which triggers adaptive survival or maladaptive apoptosis in renal tubules in diabetic kidney disease (DKD). Therapeutic strategies targeting ER stress are promising for the treatment of DKD. Here, we report a previously unappreciated role played by ENTPD5 in alleviating renal injury by mediating ER stress. We found that ENTPD5 was highly expressed in normal renal tubules; however, ENTPD5 was dynamically expressed in the kidney and closely related to pathological DKD progression in both human patients and mouse models. Overexpression of ENTPD5 relieved ER stress in renal tubular cells, leading to compensatory cell proliferation that resulted in hypertrophy, while ENTPD5 knockdown aggravated ER stress to induce cell apoptosis, leading to renal tubular atrophy and interstitial fibrosis. Mechanistically, ENTPD5-regulated N-glycosylation of proteins in the ER to promote cell proliferation in the early stage of DKD, and continuous hyperglycemia activated the hexosamine biosynthesis pathway (HBP) to increase the level of UDP-GlcNAc, which driving a feedback mechanism that inhibited transcription factor SP1 activity to downregulate ENTPD5 expression in the late stage of DKD. This study was the first to demonstrate that ENTPD5 regulated renal tubule cell numbers through adaptive proliferation or apoptosis in the kidney by modulating the protein N-glycosylation rate in the ER, suggesting that ENTPD5 drives cell fate in response to metabolic stress and is a potential therapeutic target for renal diseases.
Assuntos
Estresse do Retículo Endoplasmático , Túbulos Renais , Rim , Animais , Humanos , Camundongos , Glicosilação , Proteínas Oncogênicas , PirofosfatasesRESUMO
Previous studies have shown mitochondrial dysfunction in various acute kidney injuries and chronic kidney diseases. Lipoic acid exerts potent effects on oxidant stress and modulation of mitochondrial function in damaged organ. In this study we investigated whether alpha lipoamide (ALM), a derivative of lipoic acid, exerted a renal protective effect in a type 2 diabetes mellitus mouse model. 9-week-old db/db mice were treated with ALM (50 mg·kg-1·d-1, i.g) for 8 weeks. We showed that ALM administration did not affect blood glucose levels in db/db mice, but restored renal function and significantly improved fibrosis of kidneys. We demonstrated that ALM administration significantly ameliorated mitochondrial dysfunction and tubulointerstitial fibrotic lesions, along with increased expression of CDX2 and CFTR and decreased expression of ß-catenin and Snail in kidneys of db/db mice. Similar protective effects were observed in rat renal tubular epithelial cell line NRK-52E cultured in high-glucose medium following treatment with ALM (200 µM). The protective mechanisms of ALM in diabetic kidney disease (DKD) were further explored: Autodock Vina software predicted that ALM could activate RXRα protein by forming stable hydrogen bonds. PROMO Database predicted that RXRα could bind the promoter sequences of CDX2 gene. Knockdown of RXRα expression in NRK-52E cells under normal glucose condition suppressed CDX2 expression and promoted phenotypic changes in renal tubular epithelial cells. However, RXRα overexpression increased CDX2 expression which in turn inhibited high glucose-mediated renal tubular epithelial cell injury. Therefore, we reveal the protective effect of ALM on DKD and its possible potential targets: ALM ameliorates mitochondrial dysfunction and regulates the CDX2/CFTR/ß-catenin signaling axis through upregulation and activation of RXRα. Schematic figure illustrating that ALM alleviates diabetic kidney disease by improving mitochondrial function and upregulation and activation of RXRα, which in turn upregulated CDX2 to exert an inhibitory effect on ß-catenin activation and nuclear translocation. RTEC renal tubular epithelial cell. ROS Reactive oxygen species. RXRα Retinoid X receptor-α. Mfn1 Mitofusin 1. Drp1 dynamic-related protein 1. MDA malondialdehyde. 4-HNE 4-hydroxynonenal. T-SOD Total-superoxide dismutase. CDX2 Caudal-type homeobox transcription factor 2. CFTR Cystic fibrosis transmembrane conductance regulator. EMT epithelial mesenchymal transition. α-SMA Alpha-smooth muscle actin. ECM extracellular matrix. DKD diabetic kidney disease. Schematic figure was drawn by Figdraw ( www.figdraw.com ).
Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Ácido Tióctico , Animais , Camundongos , Ratos , beta Catenina/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/patologia , Transição Epitelial-Mesenquimal , Fibrose/tratamento farmacológico , Fibrose/metabolismo , Glucose/metabolismo , Rim/patologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Ácido Tióctico/farmacologia , Ácido Tióctico/uso terapêutico , Receptor X Retinoide alfa/efeitos dos fármacos , Receptor X Retinoide alfa/metabolismoRESUMO
ß-Lactams have been a clinical focus since their emergence and indeed act as a powerful tool to combat severe bacterial infections, but their effectiveness is threatened by drug resistance in bacteria, primarily by the production of serine- and metallo-ß-lactamases. Although once of less clinical relevance, metallo-ß-lactamases are now increasingly threatening. The rapid dissemination of resistance mediated by metallo-ß-lactamases poses an increasing challenge to public health worldwide and comprises most existing antibacterial chemotherapies. Regrettably, there have been no clinically available inhibitors of metallo-ß-lactamases until now. To cope with this unique challenge, researchers are exploring multidimensional strategies to combat metallo-ß-lactamases. Several studies have been conducted to develop new drug candidates or calibrate already available drugs against metallo-ß-lactamases. To provide an overview of this field and inspire more researchers to explore it further, we outline some promising candidates targeting metallo-ß-lactamase producers, with a focus on Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii. Promising candidates in this review are composed of new antibacterial drugs, non-antibacterial drugs, antimicrobial peptides, natural products, and zinc chelators, as well as their combinations with existing antibiotics. This review may provide ideas and insight for others to explore candidate metallo-ß-lactamases as well as promote the improvement of existing data to obtain further convincing evidence.