ABSTRACT
In this work, an electrochemiluminescence (ECL) biosensor based on dual ECL quenching effects of silver nanoclusters (Ag NCs) and multiple cycling amplification was designed to achieve ultrasensitive detection of ATP. The specific recognition of target ATP to aptamer initiated multiple cycling amplification, and a small amount of target was converted into a large number of DNA product chains (S1) by amplification. After S1 opened hairpin DNA 2 (HP2), Ag NCs approached the surface of CdS quantum dots (QDs) modified-electrode by complementary DNA, resulting in a significant decrease of ECL intensity from CdS QDs. The quenching principle is as follows. Firstly, the absorption spectrum of Ag NCs overlaps well with the ECL emission spectrum of CdS QDs, leading to effective ECL resonance energy transfer (ECL-RET); Secondly, Ag NCs could catalyze electrochemical reduction of K2S2O8, leading to consumption of ECL co-reactant and reducing ECL of QDs. The double-ECL quenching achieved ultrasensitive biosensing detection of ATP with a wide range from 1 aM to 1 pM. This present work reported new principle of double-quenching QDs ECL by Ag NCs, and developed a novel ECL biosensor by combining with multiple cycle amplification technique, which has great contribution to the development of QDs ECL and biosensing applications.
Subject(s)
Biosensing Techniques , Cadmium Compounds , Silver , Electrochemical Techniques/methods , Luminescent Measurements/methods , DNA/genetics , Biosensing Techniques/methods , Adenosine TriphosphateABSTRACT
The neuropeptide AgRP is essential for maintaining systemic energy homeostasis. In the current study, we show that hypothalamic Foxi2, as a novel regulator of nutrient sensing, controls systemic energy metabolism by specifically stimulating AgRP expression. Foxi2 was highly expressed in the hypothalamus, and its expression was induced by fasting. Immunofluorescence assays demonstrated that Foxi2 was localized in AgRP neurons. We stereotactically injected adeno-associated virus to selectively overexpress Foxi2 in AgRP-IRES-Cre mice and found that Foxi2 overexpression in AgRP neurons specifically increased AgRP expression, thereby increasing food intake and reducing energy expenditure, subsequently leading to obesity and insulin resistance. Mechanistically, Foxi2 stimulated AgRP expression by directly binding to it and activating its transcription. Furthermore, Foxi2 overexpression activated AgRP neuron activity, as revealed by whole-cell patch-clamp experiments. Conversely, global Foxi2-mutant mice became leaner with age and were resistant to high-fat diet-induced obesity and metabolic disturbances. Collectively, our data suggest that Foxi2 plays an important role in controlling energy metabolism by regulating AgRP expression.
Subject(s)
Forkhead Transcription Factors , Neuropeptides , Agouti-Related Protein/genetics , Agouti-Related Protein/metabolism , Animals , Energy Metabolism/genetics , Forkhead Transcription Factors/metabolism , Hypothalamus/metabolism , Mice , Neuropeptides/genetics , Neuropeptides/metabolism , Obesity/genetics , Obesity/metabolism , Transcription FactorsABSTRACT
Traditional Chinese medicine (TCM) is widely used in China, but the large variety can easily lead to difficulties in visual identification. This study aims to evaluate the availability of target detection models to identify TCMs. We have collected images of 100 common TCMs in pharmacies, and use three current mainstream target detection models: Faster RCNN, SSD, and YOLO v5 to train the TCM dataset. By comparing the metrics of the three models, the results show that the YOLO v5 model has obvious advantages in the recognition of a variety of TCM, the mean average accuracy of the YOLO v5 is 94.33% and the FPS has reached 75, this model has a smaller number of parameters and solves the problem of detection and occlusion for small targets. Our experiments prove that the target detection technology has broad application prospects in the detection of TCM.
ABSTRACT
Background: Prescription errors impact the safety and efficacy of therapy and are considered to have a higher impact on paediatric populations. Nevertheless, information in paediatrics is still lacking, particularly in primary care settings. There exists a need to investigate the prevalence and characteristics of prescription errors in paediatric outpatients to prevent such errors during the prescription stage. Methods: A cross-sectional study to evaluate paediatric prescription errors in multi-primary care settings was conducted between August 2019 and July 2021. Prescriptions documented within the electronic pre-prescription system were automatically reviewed by the system and then, potentially inappropriate prescriptions would be reconciled by remote pharmacists via a regional pharmacy information exchange network. The demographics of paediatric patients, prescription details, and types/rates of errors were assessed and used to identify associated factors for prescription using logistic regression. Results: A total of 39,754 outpatient paediatric prescriptions in 13 community health care centres were reviewed, among which 1,724 prescriptions (4.3%) were enrolled in the study as they met the inclusion criteria. Dose errors were the most prevalent (27%), with the predominance of underdosing (69%). They were followed by errors in selection without specified indications (24.5%), incompatibility (12.4%), and frequency errors (9.9%). Among critical errors were drug duplication (8.7%), contraindication (.9%), and drug interaction (.8%) that directly affect the drug's safety and efficacy. Notably, error rates were highest in medications for respiratory system drugs (50.5%), antibiotics (27.3%), and Chinese traditional medicine (12.3%). Results of logistic regression revealed that specific drug classification (antitussives, expectorants and mucolytic agents, anti-infective agents), patient age (<6 years), and prescriber specialty (paediatrics) related positively to errors. Conclusion: Our study provides the prevalence and characteristics of prescription errors of paediatric outpatients in community settings based on an electronic pre-prescription system. Errors in dose calculations and medications commonly prescribed in primary care settings, such as respiratory system drugs, antibiotics, and Chinese traditional medicine, are certainly to be aware of. These results highlight an essential requirement to update the rules of prescriptions in the pre-prescription system to facilitate the delivery of excellent therapeutic outcomes.
ABSTRACT
INTRODUCTION: The cognitive dysfunction associated with nitrous oxide abuse is gradually becoming a major global public health concern. Despite the increasing prevalence of nitrous oxide abuse, there are currently no authorised/approved treatment options. Hyperbaric oxygen therapy (HBOT) has been proven to be an efficient method to improve cognitive function. The current randomised, double-blinded, placebo-controlled trial will explore the effect of HBOT on cognitive dysfunction induced by nitrous oxide abuse. METHODS AND ANALYSIS: Eighty participants who abuse nitrous oxide and have cognitive dysfunction, including memory decline, disorientation, attention deficits, slower reactions and learning disabilities, will be included in the trial. They will be randomly assigned to receive either HBOT or sham-HBOT 90-120 min once daily for 5 days per week for 2 weeks. The primary outcome will be the improvement in the total score of the MATRICS Consensus Cognitive Battery, which will measure comprehensive cognitive function between the two groups. Additionally, attention will be measured by integrated visual and auditory continuous performance tests, executive function will be measured by the Wisconsin card sorting test, intelligence will be measured by Raven's standard progressive matrices and cognitive control will be measured by the Stroop colour word interference test. ETHICS AND DISSEMINATION: This protocol was approved by the West China Hospital of Sichuan University Biomedical Research Ethics Committee. The report of the study will be disseminated via scientific forums including peer-reviewed publications and presentations at national and international conferences. TRIAL REGISTRATION NUMBER: Chinese Clinical Trial Registry (ChiCTR2100047111).
Subject(s)
Cognitive Dysfunction , Hyperbaric Oxygenation , Cognition , Cognitive Dysfunction/chemically induced , Cognitive Dysfunction/therapy , Double-Blind Method , Humans , Nitrous Oxide , Randomized Controlled Trials as Topic , Research DesignABSTRACT
Solving the problem of rural sewage is considered an essential task in China's rural revitalization strategy. Based on the yearbook data of sewage treatment in rural areas between 2014 and 2019, although the rate of sewage treatment in rural areas of China showed an upward trend, it was still below 35%, mainly due to the lack of suitable sewage treatment technologies. Here, we discuss the multi-soil-layering (MSL) system, which is an emerging technology suitable for rural sewage treatment. It was deemed to overcome the shortcomings of current biological and ecological treatment technologies, such as complex operation, large area, and high operating costs. We used system dynamics to evaluate the advancing and limiting factors of MSL application for rural sewage treatment from the social, environmental, and economic dimensions. The results illustrated a complete causal loop diagram in which essential variables and relationships were concentrated in the technology, operation and maintenance, and satisfaction of farmers. The efficiency of MSL is the key variable affecting the final decision of the MSL application. Overall, using MSL to treat rural sewage could be an option to improve the rural environment in China. However, the scientific technological model for MSL should be further explored. This review provides guidance on how to promote MSL systems in rural areas.
Subject(s)
Sewage , Soil , ChinaABSTRACT
Cantharidin (CTD) is the main bioactive component of Cantharides, which is called Banmao in Traditional Chinese Medicine (TCM). Norcantharidin (NCTD) is a structural modifier of CTD. To compare with CTD, NCTD has lighter side effects and stronger bioactivity in anti-cancer through inhibiting cell proliferation, causing apoptosis and autophagy, overwhelming migration and metastasis, affecting immunity as well as lymphangiogenesis. Examples of these effects include suppressing Protein Phosphatase 2A and modulating Wnt/beta catenin signal, with Caspase family proteins, AMPK pathway and c-Met/EGFR pathway involving respectively. Moreover, NCTD has the effects of immune enhancement, anti-platelet aggregation and inhibition of renal interstitial fibrosis with distinct signaling pathways. The immunological effects induced by NCTD are related to the regulation of macrophage polarization and LPS-mediated immune response. The antiplatelet activity that NCTD induced is relevant to the inhibition of platelet signaling and the downregulation of α2 integrin. Furthermore, some of novel derivatives designed and synthesized artificially show stronger biological activities (e.g., anticancer effect, enzyme inhibition effect, antioxidant effect) and lower toxicity than NCTD itself. Plenty of literatures have reported various pharmacological effects of NCTD, particularly the anticancer effect, which has been widely concerned in clinical application and laboratory research. In this review, the pharmaceutical activities and derivatives of NCTD are discussed, which can be reference for further study.
Subject(s)
Antineoplastic Agents/pharmacology , Bridged Bicyclo Compounds, Heterocyclic/pharmacology , Neoplasms/drug therapy , Animals , Apoptosis/drug effects , Autophagy/drug effects , Cantharidin/chemistry , Cell Proliferation/drug effects , Humans , Medicine, Chinese Traditional , Neoplasms/pathologyABSTRACT
Psoralen is the principal bioactive component in the dried fruits of Cullen corylifolium (L.) Medik (syn. Psoralea corylifolia L), termed "Buguzhi" in traditional Chinese medicine (TCM). Recent studies have demonstrated that psoralen displays multiple bioactive properties, beneficial for the treatment of osteoporosis, tumors, viruses, bacteria, and inflammation. The present review focuses on the research evidence relating to the properties of psoralen gathered over recent years. Firstly, multiple studies have demonstrated that psoralen exerts strong anti-osteoporotic effects via regulation of osteoblast/osteoclast/chondrocyte differentiation or activation due to the participation in multiple molecular mechanisms of the wnt/ß-catenin, bone morphogenetic protein (BMP), inositol-requiring enzyme 1 (IRE1)/apoptosis signaling kinase 1 (ASK1)/c-jun N-terminal kinase (JNK) and the Protein Kinase B(AKT)/activator protein-1 (AP-1) axis, and the expression of miR-488, peroxisome proliferators-activated receptor-gamma (PPARγ), and matrix metalloproteinases (MMPs). In addition, the antitumor properties of psoralen are associated with the induction of ER stress-related cell death via enhancement of PERK: Pancreatic Endoplasmic Reticulum Kinase (PERK)/activating transcription factor (ATF), 78kD glucose-regulated protein (GRP78)/C/EBP homologous protein (CHOP), and 94kD glucose-regulated protein (GRP94)/CHOP signaling, and inhibition of P-glycoprotein (P-gp) or ATPase that overcomes multidrug resistance. Furthermore, multiple articles have shown that the antibacterial, anti-inflammatory and neuroprotective effects of psoralen are a result of its interaction with viral polymerase (Pol), destroying the formation of biofilm, and regulating the activation of tumor necrosis factor alpha (TNF-α), transforming growth factor beta (TGF-ß), interleukin 4/5/6/8/12/13 (IL-4/5/6/8/12/13), GATA-3, acetylcholinesterase (AChE), and the hypothalamic-pituitary-adrenal (HPA) axis. Finally, the toxic effects and mechanisms of action of psoralen have also been reviewed.
ABSTRACT
Cordycepin is the major bioactive component extracted from Cordyceps militaris. In recent years, cordycepin has received increasing attention owing to its multiple pharmacological activities. This study reviews recent researches on the anti-inflammatory effects and the related activities of cordycepin. The results from our review indicate that cordycepin exerts protective effects against inflammatory injury for many diseases including acute lung injury (ALI), asthma, rheumatoid arthritis, Parkinson's disease (PD), hepatitis, atherosclerosis, and atopic dermatitis. Cordycepin regulates the NF-κB, RIP2/Caspase-1, Akt/GSK-3ß/p70S6K, TGF-ß/Smads, and Nrf2/HO-1 signaling pathways among others. Several studies focusing on cordycepin derivatives were reviewed and found to down metabolic velocity of cordycepin and increase its bioavailability. Moreover, cordycepin enhanced immunity, inhibited the proliferation of viral RNA, and suppressed cytokine storms, thereby suggesting its potential to treat COVID-19 and other viral infections. From the collected and reviewed information, this article provides the theoretical basis for the clinical applications of cordycepin and discusses the path for future studies focusing on expanding the medicinal use of cordycepin. Taken together, cordycepin and its analogs show great potential as the next new class of anti-inflammatory agents.
ABSTRACT
Adjuvants that contain pathogen-associated molecular patterns (PAMPs) can enhance vaccination efficacy by binding to pattern recognition receptors (PRRs), thereby stimulating immune responses. Particularly effective may be the combination of multiple PAMPs that activate different PRRs, which occurs with natural pathogens. Here we hypothesized the enhanced effects would occur in two adjuvants that stimulate different PRRs: CpG oligodeoxynucleotide (CpG-ODN), which is Toll-like receptor 9 agonist; and 5'-triphosphate, short, double-stranded RNA (3pRNA), which activates retinoic acid-inducible gene I (RIG-I). The model antigen ovalbumin (OVA) was loaded and adjuvants were surface-adsorbed to aluminum hydroxide nanoparticles (hereafter NP-3pRNA-CpG) by electrostatic interaction with an average size of 120 nm and a negative surface charge for targeting lymph nodes. These nanoparticles were efficiently internalized by antigen-presenting cells (APCs) in the lymph nodes, and the resulting APC activation and antigen cross-presentation generated strong humoral immunity and cytotoxic T lymphocyte responses and IFN-γ secretion. NP-3pRNA-CpG significantly suppressed B16-OVA tumor growth and prolonged survival of tumor-bearing mice in therapeutic and prophylactic models, illustrating the enhanced effects of CpG-ODN and 3pRNA. Our study highlights the potential of combining multiple adjuvants for effective vaccine design.
Subject(s)
Aluminum Hydroxide , Nanoparticles , Adjuvants, Immunologic , Animals , Antigens , Mice , Mice, Inbred C57BL , Oligodeoxyribonucleotides , OvalbuminABSTRACT
Five previously undescribed compounds, including two dendrobine-type alkaloids (1 and 2), three bibenzyl derivatives (3-5), along with six known compounds were isolated from orchids Dendrobium findlayanum. The structures and absolute configurations of the undescribed compounds were elucidated on the basis of HR-ESIMS, NMR spectroscopy, optical rotation value, as well as electronic circular dichroism (ECD) calculations. The cytotoxic effects of the isolated compounds on three human tumour cell lines (A172, SHSY5Y, and Hela) were evaluated by the MTT assay. Compound 6 showed excellent inhibitory activities against three human tumour cell lines with IC50 ranging from 1.65 µM to 3.77 µM. All these compounds were assessed for their activity of promoting the gastrointestinal motility of zebrafish treated with Nile red. Compound 6 have excellent activity to promote the gastrointestinal motility of zebrafish at the concentration of 0.3 µM.
Subject(s)
Alkaloids/chemistry , Bibenzyls/chemistry , Dendrobium/chemistry , Alkaloids/isolation & purification , Animals , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Bibenzyls/isolation & purification , Cell Line, Tumor , Cell Survival/drug effects , Gastrointestinal Agents/chemistry , Gastrointestinal Agents/pharmacology , Gastrointestinal Motility/drug effects , Humans , Larva/drug effects , Models, Molecular , Molecular Structure , ZebrafishABSTRACT
Shikonin is the major bioactive component extracted from the roots of Lithospermum erythrorhizon which is also known as "Zicao" in Traditional Chinese Medicine (TCM). Recent studies have shown that shikonin demonstrates various bioactivities related to the treatment of cancer, inflammation, and wound healing. This review aimed to provide an updated summary of recent studies on shikonin. Firstly, many studies have demonstrated that shikonin exerts strong anticancer effects on various types of cancer by inhibiting cell proliferation and migration, inducing apoptosis, autophagy, and necroptosis. Shikonin also triggers Reactive Oxygen Species (ROS) generation, suppressing exosome release, and activate anti-tumor immunity in multiple molecular mechanisms. Examples of these effects include modulating the PI3K/AKT/mTOR and MAPKs signaling; inhibiting the activation of TrxR1, PKM2, RIP1/3, Src, and FAK; and regulating the expression of ERP57, MMPs, ATF2, C-MYC, miR-128, and GRP78 (Bip). Next, the anti-inflammatory and wound-healing properties of shikonin were also reviewed. Furthermore, several studies focusing on shikonin derivatives were reviewed, and these showed that, with modification to the naphthazarin ring or side chain, some shikonin derivatives display stronger anticancer activity and lower toxicity than shikonin itself. Our findings suggest that shikonin and its derivatives could serve as potential novel drug for the treatment of cancer and inflammation.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Antineoplastic Agents, Phytogenic/therapeutic use , Naphthoquinones/therapeutic use , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Endoplasmic Reticulum Chaperone BiP , Humans , Lithospermum/chemistry , Naphthoquinones/chemistry , Naphthoquinones/pharmacology , Neoplasms/drug therapy , Neoplasms/immunology , Wound Healing/drug effectsABSTRACT
Paris polyphylla. is a traditional medicinal herb that has long been used to prevent cancer in many Asian countries. Polyphyllin I (PPI), an important bioactive constituent of Paris polyphylla, has been found to exhibit a wide variety of anticancer activities in many types of cancer cells. However, the effects of PPI on human gastric carcinoma cells and its mechanism of action remain unclear. In this study, we examined the effective anti-gastric carcinoma activity of PPI and its underlying mechanism of action in HGC-27 cells. In vitro, sub-micromolar concentrations of PPI inhibited HGC-27 cell proliferation with an IC50 of 0.34 ± 0.06 µM after a 72-h treatment. In vivo, 3 mg/kg PPI significantly inhibited proliferation of HGC-27 tumor cells, with a 78.8% inhibition rate compared to paclitaxel, and demonstrated higher safety. Analysis of MDC and mGFP-LC3 fluorescence, Western blotting and flow cytometry indicated that PPI induced cell cycle arrest in HGC-27 cells by promoting the conversion of LC3-I to LC3-II and by downregulating cyclin B1. Furthermore, Western blotting showed that PPI inhibited the autophagy-regulating PDK1/Akt/mTOR signaling pathway in vitro and in vivo. In addition, immunohistochemistry and TUNEL staining revealed that PPI decreased Ki67 expression and increased the percentage of apoptotic cells in HGC-27 xenograft tumors. These data indicate that PPI is an PDK1/Akt/mTOR signaling inhibitor and of therapeutic relevance for gastric cancer treatment and that the rhizome of Paris polyphylla deserves further clinical investigation as an alternative therapy for gastric cancer.
Subject(s)
Autophagy/drug effects , Cell Cycle Checkpoints/drug effects , Diosgenin/analogs & derivatives , Down-Regulation/drug effects , Signal Transduction/drug effects , Stomach Neoplasms/drug therapy , 3-Phosphoinositide-Dependent Protein Kinases/metabolism , Cell Line, Tumor , Cyclin B1/metabolism , Diosgenin/pharmacology , Humans , Proto-Oncogene Proteins c-akt/metabolism , Stomach Neoplasms/metabolism , TOR Serine-Threonine Kinases/metabolismABSTRACT
Two new terpene glycosides (1-2) along with two known analogs (3-4) were obtained from the root of Sanguisorba officinalis, which is a common traditional Chinese medicine (TCM). Their structures were elucidated by nuclear magnetic resonance (NMR), electrospray ionization high resolution mass spectrometry (HRESIMS), and a hydrolysis reaction, as well as comparison of these data with the literature data. Compounds 1-4 exhibited anti-inflammatory properties in vitro by attenuating the production of inflammatory mediators, such as nitric oxide (NO) as well as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). An anti-inflammatory assay based on the zebrafish experimental platform indicated that compound 1 had good anti-inflammatory activity in vivo by not only regulating the distribution, but also by reducing the amount of the macrophages of the zebrafish exposed to copper sulfate.
Subject(s)
Anti-Inflammatory Agents , Glycosides , Sanguisorba/chemistry , Terpenes , Animals , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/isolation & purification , Anti-Inflammatory Agents/pharmacology , Glycosides/chemistry , Glycosides/isolation & purification , Glycosides/pharmacology , Inflammation/drug therapy , Inflammation/metabolism , Inflammation/pathology , Interleukin-6/metabolism , Mice , Nitric Oxide/metabolism , RAW 264.7 Cells , Terpenes/chemistry , Terpenes/isolation & purification , Terpenes/pharmacology , Tumor Necrosis Factor-alpha/metabolism , ZebrafishABSTRACT
Metal-organic frameworks (MOFs) have high surface area, tunable pore size, and high loading capacity, making them promising for drug delivery. However, their synthesis requires organic solvents, high temperature and high pressure that are incompatible with biomacromolecules. Zeolitic imidazole frameworks (ZIF-8) which forms through coordination between zinc ions and 2-methylimidazole (MeIM) have emerged as an advanced functional material for drug delivery due to its unique features such as high loading and pH-sensitive degradation. In this study, we took advantage of a natural biomineralization process to create aluminum-containing nanoZIF-8 particles for antigen delivery. Without organic solvents or stabilizing agent, nanoparticles (ZANPs) were synthesized by a mild and facile method with aluminum, model antigen ovalbumin (OVA) and ZIF-8 integrated. A high antigen loading capacity (%) of 30.6% and a pH dependent antigen release were achieved. A Toll-like receptor 9 agonist cytosine-phosphate-guanine oligodeoxynucleotides (CpG) was adsorbed on the surface of ZANPs (hereafter CpG/ZANPs) to boost the immune response. After subcutaneous injection in vivo, CpG/ZANPs targeted lymph nodes (LNs), where their cargo was efficiently internalized by LN-resident antigen-presenting cells (APCs). ZANPs decomposition in lysosomes released antigen into the cytoplasm and enhanced cross-presentation. Moreover, CpG/ZANPs induced strong antigen-specific humoral and cytotoxic T lymphocyte responses that significantly inhibited the growth of EG7-OVA tumors while showing minimal cytotoxicity. We demonstrate that ZANPs may be a safe and effective vehicle for the development of cancer vaccines.
Subject(s)
Adjuvants, Immunologic/administration & dosage , Aluminum Chloride/administration & dosage , Antigens/administration & dosage , Metal-Organic Frameworks/administration & dosage , Nanoparticles/administration & dosage , Oligodeoxyribonucleotides/administration & dosage , Ovalbumin/administration & dosage , T-Lymphocytes, Cytotoxic/drug effects , Zeolites/administration & dosage , Animals , Cell Line , Female , Imidazoles/administration & dosage , Immunity, Cellular/drug effects , Immunity, Humoral/drug effects , Lymph Nodes/immunology , Mice, Inbred C57BL , Neoplasms/drug therapy , Neoplasms/immunologyABSTRACT
Alterations in the synthesis and bioavailability of NO are central to the pathogenesis of cardiovascular and metabolic disorders. Although endothelial NO synthase-derived (eNOS-derived) NO affects mitochondrial long-chain fatty acid ß-oxidation, the pathophysiological significance of this regulation remains unclear. Accordingly, we determined the contributions of eNOS/NO signaling in the adaptive metabolic responses to fasting and in age-induced metabolic dysfunction. Four-month-old eNOS-/- mice are glucose intolerant and exhibit serum dyslipidemia and decreased capacity to oxidize fatty acids. However, during fasting, eNOS-/- mice redirect acetyl-CoA to ketogenesis to elevate circulating levels of ß-hydroxybutyrate similar to wild-type mice. Treatment of 4-month-old eNOS-/- mice with nitrite for 10 days corrected the hypertension and serum hyperlipidemia and normalized the rate of fatty acid oxidation. Fourteen-month-old eNOS-/- mice exhibited metabolic derangements, resulting in reduced utilization of fat to generate energy, lower resting metabolic activity, and diminished physical activity. Seven-month administration of nitrite to eNOS-/- mice reversed the age-dependent metabolic derangements and restored physical activity. While the eNOS/NO signaling is not essential for the metabolic adaptation to fasting, it is critical for regulating systemic metabolic homeostasis in aging. The development of age-dependent metabolic disorder is prevented by low-dose replenishment of bioactive NO.
Subject(s)
Aging/metabolism , Homeostasis/drug effects , Nitric Oxide Synthase Type III/deficiency , Sodium Nitrite/administration & dosage , Administration, Oral , Aging/drug effects , Animals , Disease Models, Animal , Drug Evaluation, Preclinical , Fasting/metabolism , Humans , Hyperlipidemias/drug therapy , Hyperlipidemias/genetics , Hyperlipidemias/metabolism , Hypertension/drug therapy , Hypertension/genetics , Hypertension/metabolism , Male , Mice , Mice, Knockout , Nitric Oxide/metabolism , Nitric Oxide Synthase Type III/genetics , Signal Transduction/drug effects , Time Factors , Treatment OutcomeABSTRACT
Alzheimer's disease (AD) is a progressive neurodegenerative dementia characterized by Aß deposition and neurofibrillary tangles (NFTs) composed of hyperphosphorylated tau. Emerging evidence shows that microRNAs (miRNAs) contribute to the pathogenesis of AD. Herein, we investigated the role of miR-138, a brain enriched miRNA, which is increased in AD patients. We found that miR-138 is increased in AD models, including N2a/APP and HEK293/tau cell lines. Overexpression of miR-138 activates glycogen synthase kinase-3ß (GSK-3ß), and increases tau phosphorylation in HEK293/tau cells. Furthermore, we confirm that retinoic acid receptor alpha (RARA) is a direct target of miR-138, and supplement of RARA substantially suppresses GSK-3ß activity, and reduces tau phosphorylation induced by miR-138. In conclusion, our data suggest that miR-138 promotes tau phosphorylation by targeting the RARA/GSK-3ß pathway.
Subject(s)
MicroRNAs/physiology , Receptors, Retinoic Acid/genetics , tau Proteins/metabolism , Alzheimer Disease/metabolism , Base Sequence , Binding Sites , Gene Expression , HEK293 Cells , Humans , Phosphorylation , Protein Processing, Post-Translational , RNA Interference , Receptors, Retinoic Acid/metabolism , Retinoic Acid Receptor alphaABSTRACT
BACKGROUND:Studies have indicated that melatonin can promote the differentiation of adipose-derived stem cels into neurons, and the effect of melatonin on the osteoblasts form adipose-derived stem cels is rarely reported. OBJECTIVE:To observe the osteogenic differentiation of adipose-derived stem cels and the effect of melatonin on the bio-viability of differentiated cels. METHODS:(1) Adipose-derived stem cels were isolated and purified from the inguinal fat of Kunming mice by type I colagenase digestion and differential adhesion method, respectively. Immunohistochemical staining of CD44 was used as a quality control. (2) Osteogenic induction medium was added to induce osteogenic differentiation of passage 2 adipose-derived stem cels. Alkaline phosphatase staining and von Kossa method were combined to evaluate differentiation condition. (3) Melatonin at variable concentrations was added to treat mature osteocytes originated from adipose-derived stem cels and MTT was applied to determine their viability at 24 and 48 hours after culture respectively to find out optimal condition of melatonin treatment. (4) Melatonin at the optimal concentration was used to treat differentiated cels and detect alkaline phosphatase activity after 3 days and 6 days respectively. RESULTS AND CONCLUSION: (1) After seeding for 48 hours, most cels were adherent, and after 4 days, the cels displayed multiple shapes and colonies of different sizes formed. After subculture, cel morphology homogenized as spindle shape. Cels positive for CD44 were brownish yelow, and localized mainly on the cel membrane. (2) Differentiated cels were positive for von Kossa staining and black sediments scattered in the extracelular matrix. Alkaline phosphatase expressed positively, and brown-black particles, appeared within cels. (3) Melatonin supplement improved the viability of differentiated cels; and 1, 10 and 100 μmol/L was observed as the optimal concentrations both at 24 and 48 hours. (4) The intracelular alkaline phosphatatse activity was increased with time in al the groups (P < 0.05). Compared with the blank group, the intracelular alkaline phosphatase activity in Melatonin groups (1, 10 and 100 μmol/L) had nochanges at 3 days, but significantly increased at 6 days (P < 0.05). These findings indicate that melatonin can enhance the proliferation of osteocytes differentiated from adipose-derived stem cels, and improve the activity of intracelular alkaline phosphatase.
ABSTRACT
Alzheimer's disease (AD) is the most prevalent type of dementia in elderly people. There are decreased melatonin levels in the serum of AD patients, and melatonin supplements are able to reverse AD pathology and memory deficits in many animal experiments and clinical trials. However, the underlying mechanism regarding how melatonin rescues the AD-like memory/synaptic disorder remains unknown. Here, we use the Morris water maze, step-down inhibitory avoidance task, in vivo long-term potentiation recording, and Golgi staining and report that intraperitoneal injection of melatonin (1 mg/kg/day) for 14 days in rats effectively reverses the memory and synaptic impairment in scopolamine-induced amnesia, a well-recognized dementia animal model. Using real-time polymerase chain reaction and western blotting experiments, we further determined that melatonin rescues the EPACs/miR-124/Egr1 signal pathway, which is important in learning and memory, as reported recently. Our studies provide a novel underlying epigenetic mechanism for melatonin to attenuate the synaptic disorder and could benefit drug discovery in neurodegenerative diseases.
Subject(s)
Early Growth Response Protein 1/metabolism , Guanine Nucleotide Exchange Factors/metabolism , Melatonin/therapeutic use , Memory Disorders/drug therapy , MicroRNAs/metabolism , Signal Transduction , Synapses/pathology , Animals , Male , Melatonin/pharmacology , Memory Disorders/physiopathology , Rats , Rats, Sprague-Dawley , Scopolamine , Signal Transduction/drug effects , Synapses/drug effects , Synaptic Transmission/drug effectsABSTRACT
Hyperhomocystinemia could induce tau protein hyperphosphorylation, ß-amyloid (Aß) accumulation, and memory deficits as seen in Alzheimer disease (AD), the most common cause of senile dementia with no effective cure currently. To search for possible treatment for AD, we produced a hyperhomocysteinemia model by vena caudalis injection of homocystine (Hcy) for 2 weeks and studied the effects of acetyl-L-carnitine (ALC) in rats. We found that simultaneous supplement of ALC could improve the Hcy-induced memory deficits remarkably, with attenuation of tau hyperphosphorylation and Aß accumulation. Supplement of ALC almost abolished the Hcy-induced tau hyperphosphorylation at multiple AD-related sites. Supplementation of ALC also suppressed the phosphorylation of ß-amyloid precursor proteins (APP), which may underlie the reduction of Aß. Our data suggest that ALC could be a promising candidate for arresting Hcy-induced AD-like pathological and behavioral impairments.