Key toxic components and sources affecting oxidative potential of atmospheric particulate matter using interpretable machine learning: Insights from fog episodes.

Fog significantly affects the air quality and human health. To investigate the health effects and mechanisms of atmospheric fine particulate matter (PM2.5) during fog episodes, PM2.5 samples were collected from the coastal suburb of Qingdao during different seasons from 2021 to 2022, with the major chemical composition in PM2.5 analyzed. The oxidative potential (OP) of PM2.5 was determined using the dithiothreitol (DTT) method. A positive matrix factorization model was adopted for PM2.5. Interpretable machine learning (IML) was used to reveal and quantify the key components and sources affecting OP. PM2.5 exhibited higher oxidative toxicity during fog episodes. Water-soluble organic carbon (WSOC), NH4+, K+, and water-soluble Fe positively affected the enhancement of DTTV (volume-based DTT activity) during fog episodes. The IML analysis demonstrated that WSOC and K+ contributed significantly to DTTV, with values of 0.31 ± 0.34 and 0.27 ± 0.22 nmol min-1 m-3, respectively. Regarding the sources, coal combustion and biomass burning contributed significantly to DTTV (0.40 ± 0.38 and 0.39 ± 0.36 nmol min-1 m-3, respectively), indicating the significant influence of combustion-related sources on OP. This study provides new insights into the effects of PM2.5 compositions and sources on OP by applying IML models.

Puerarin improves busulfan-induced disruption of spermatogenesis by inhibiting MAPK pathways.

Male infertility is a global concern, with a noticeable increase in the decline of spermatogenesis and sperm quality. However, there are limited clinically effective treatments available. This study aimed to investigate the potential effectiveness of puerarin in treating male infertility, which leads to gonadal changes. The results obtained from various analyses such as CASA, immunofluorescence, DIFF-Quick, hematoxylin and eosin (H&E), and periodic acid-Schiff (PAS) staining demonstrated that puerarin supplementation significantly alleviated the busulfan-induced reduction in spermatogenesis and sperm quality in both young and adult mice. Furthermore, puerarin exhibited a marked improvement in the damage caused by busulfan to the architecture of seminiferous tubules, causal epididymis, blood-testicular barrier (BTB), as well as spermatogonia and Sertoli cells. Similarly, puerarin significantly reduced the levels of total antioxidant capacity (T-AOC), malondialdehyde (MDA), and caspase-3 in the testes of busulfan-induced mice, as determined by microplate reader analysis. Additionally, RNA-seq data, RT-qPCR, and western blotting revealed that puerarin restored the abnormal gene expressions induced by busulfan to nearly healthy levels. Notably, puerarin significantly reversed the impact of busulfan on the expression of marker genes involved in spermatogenesis and oxidative stress. Moreover, puerarin suppressed the phosphorylation of p38, ERK1/2, and JNK in the testes, as observed through testicular analysis. Consequently, this study concludes that puerarin may serve as a potential alternative for treating busulfan-induced damage to male fertility by inactivating the testicular MAPK pathways. These findings may pave the way for the use of puerarin in addressing chemotherapy- or other factors-induced male infertility in humans.

GAS5 protects against nonalcoholic fatty liver disease via miR-28a-5p/MARCH7/NLRP3 axis-mediated pyroptosis.

Nonalcoholic fatty liver disease (NAFLD) is characterised by hepatic steatosis, inflammation, and insulin resistance. The role of long noncoding RNA (lncRNA)-regulated pyroptosis in NAFLD development remains largely unknown. This study aimed to investigate whether NAFLD development is controlled by lncRNA growth-arrest specific transcript 5 (GAS5)/miR-28a-5p/membrane associated ring-CH-type finger 7 (MARCH7)-mediated pyroptosis using in vivo and in vitro models. First, GAS5 expression was decreased but miR-28a-5p expression was increased in the livers of NAFLD patients, high-fat diet (HFD)-fed mice and leptin-deficient obese (Ob/Ob) mice. Furthermore, GAS5 suppressed while miR-28a-5p promoted NAFLD development, and overexpression of miR-28a-5p reversed the GAS5 overexpression-induced attenuation of NAFLD. Mechanistically, GAS5 served as a sponge of miR-28a-5p, and miR-28a-5p enhanced pyroptosis by targeting the 3' untranslated region (UTR) of the E3 ligase MARCH7 during NAFLD development. MARCH7 interacted with the NOD-like receptor protein 3 (NLRP3) protein, resulting in proteasomal degradation of NLRP3 to inhibit pyroptosis. As expected, MARCH7 knockdown abolished the miR-28a-5p knockdown-induced inhibition of NAFLD development, and the ubiquitin E3 ligase-inactive mutant (W589A/I556A) of MARCH7 failed to inhibit NAFLD development. In conclusion, GAS5 protected against NAFLD development by binding to miR-28a-5p, miR-28a-5p promoted NAFLD development by targeting MARCH7, and MARCH7 ameliorated NAFLD by suppressing NLRP3-mediated pyroptosis. The GAS5/miR-28a-5p/MARCH7/NLRP3 axis plays an important role in NAFLD progression, and it might be a biomarker for NAFLD.

Puerarin extends the lifespan of Drosophila melanogaster by activating autophagy.

Lifespan longevity has attracted increasing attention with societal development. To counter the effects of aging on longevity, we focused on the natural chemicals of plants. In this study, we investigated the effects of puerarin supplementation on the lifespan of Drosophila melanogaster. Puerarin supplementation significantly extended the lifespan of D. melanogaster at 60 µM and 120 µM by upregulating proteasome subunit beta 5 (prosbeta5) and sirtuin-1 (Sirt1). However, puerarin-induced longevity of male flies (F0 generation) may not be passed on to descendants. Additionally, a puerarin diet for 10 and 25 days did not influence the body weight and food intake of male Canton-S flies. Puerarin significantly improved the climbing ability, starvation resistance, and oxidation resistance of male flies by upregulating the expression of Shaker, catalase (CAT), superoxide dismutase 1 (SOD1), and Methuselah, and downregulating poly [ADP-ribose] polymerase (PARP-1) and major heat shock 70 kDa protein Aa (HSP70). Moreover, 120 µM puerarin supplementation for 25 days significantly increased adenosine 5' triphosphate (ATP) content by increasing adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) levels. Additionally, the puerarin diet for 25 days suppressed male fecundity in male flies by decreasing the levels of Bam and Punt. Mechanistically, puerarin enhanced lysosome-involved autophagy by promoting the expression of lysosome markers [ß-galactosidase and lysosomal associated membrane protein 1 (LAMP1)], and elevating the levels of autophagy-related genes, including autophagy-associated gene 1 (ATG1), ATG5, and ATG8b. However, puerarin decreased the phosphorylation of the target of rapamycin (TOR) protein. In conclusion, puerarin is a promising compound for improving the longevity of D. melanogaster by activating autophagy.

A case report of primary cardiac angiosarcoma with DNMT3A gene mutation.

Cardiac angiosarcoma is a rare disease with a high mortality rate despite its low incidence. Surgery is currently the mainstay treatment strategy for patients with this condition. Herein, we describe a case of primary cardiac angiosarcoma, including symptoms, examination findings, treatment strategy and prognosis. In 2020, the patient was admitted to our hospital, and Next-Generation Sequencing (NGS) revealed a mutation in the DNMT3A gene. Generally, DNMT3A mutations are most commonly seen in atherosclerosis and myeloid leukemia. To our knowledge, this is the first reported case of primary cardiac angiosarcoma with DNMT3A gene mutation.

Event-triggered adaptive sliding mode control for consensus of multiagent systems with unknown disturbances.

In this paper, a novel robust distributed consensus control scheme based on event-triggered adaptive sliding mode control is proposed for multiagent systems with unknown disturbances in a leader-follower framework. First, an adaptive multivariate disturbance observer is utilized to compensate for the disturbance of each agent. Next, a distributed consensus control protocol is constructed via integral sliding mode control, in which a novel adaptive law is designed for the switching gain to overcome the unknown perturbations. An event-triggered strategy is designed to update the control input. Furthermore, the feasibility of the proposed scheme is rigorously analyzed by Lyapunov theory, and a lower bound expression for the inter-event time is derived to guarantee that Zeno behavior can be excluded. The proposed nonlinear consensus algorithm is remarkable in that it does not require any information about the bounds of the disturbances. Finally, compared with existing methods, the proposed algorithm is validated through detailed numerical simulations. In addition, the proposed algorithm is applied to a group of UAVs in this paper, and the results show that it has more application value.

Cholangiocarcinoma presenting as dysphagia and misdiagnosed as gastritis: a case report.

BACKGROUND: Heterotopic tumor is a rare disease. Thus far, no cases of heterotopic cholangiocarcinoma have been reported in the world. Cholangiocarcinoma mainly metastasizes by direct invasion, and it can lead to liver metastasis in its advanced stage. There were few clinical cases of gastric metastasis in advanced tumors, mainly seen in breast cancer, lung cancer, liver cancer, malignant melanoma, choriocarcinoma, and hematological tumors. Metastases of cholangiocarcinoma to the stomach also are exceptionally rare. CASE PRESENTATION: A 58-year-old man was admitted to the hospital because of difficulty swallowing for one year. Upon gastroscopy, we found the tumor at the region of the cardia and gastric fundus. Macroscopical appearance of the tumor suggested its malignant nature. Computed tomography (CT) findings showed that the wall of the cardia, fundus, and stomach body were thickened, suggesting a tumor. Because the patient had obvious difficulty swallowing, we invited cardiothoracic surgeons for consultation. They considered that the patient had definite mechanical obstruction in the lower esophagus; hence, they performed an operation. Immunohistochemical staining revealed low-to-medium differentiated adenocarcinoma (containing mucinous adenocarcinoma components) of biliary origin. CONCLUSIONS: We highlight the importance of the endoscopic biopsy of gastric tumor. However, when its results are inconsistent with the clinician's judgment, further examination is required. Endoscopic ultrasonography and enhanced CT may be a good choice. If necessary, on the premise of patient acceptance, the diagnosis could be confirmed after surgical excision. Here we report a case of a patient with heterotopic cholangiocarcinoma in the gastric fundus. The most common tissue ectopias in the digestive tract include esophagogastric gastric mucosal ectopia, duodenal gastric mucosal ectopia, and gastric mucosal small intestinal ectopia. Thus far, there have been no reports of ectopic cholangiocarcinoma and associated cancer in the stomach. In addition, metastases of cholangiocarcinoma to the stomach are also exceptionally rare, and most of them are due to a direct invasion. The discovery of the primary lesion is an important clue for the reliable diagnosis in such cases.

Cellulose nanocrystals reinforced highly stretchable thermal-sensitive hydrogel with ultra-high drug loading.

Hydrogels often have poor mechanical properties which limit their application in load-bearing tissues such as muscle and cartilage. In this work, a near-infrared light-triggered stretchable thermal-sensitive hydrogel with ultra-high drug loading was developed by a combination of natural polymeric nanocrystals, a network of synthetic thermo-responsive polymer, and magnetic Fe3O4 nanoparticles. The hydrogels comprise cellulose nanocrystals (CNCs) decorated with Fe3O4 nanoparticles (Fe3O4/CNCs) dispersed homogeneously in poly(N-isopropylacrylamide) (PNIPAm) networks. The composite hydrogels exhibit an extensibility of 2200%. Drug loading of vancomycin (VCM) reached a high value of 10.18 g g-1 due to the dispersion of Fe3O4/CNCs and the interactions between the CNCs and the PNIPAm network. Importantly, the hydrogels demonstrated a thermo-response triggered by NIR, with the temperature increasing from 26 to 41 °C within 60 s. The hydrogels have high biocompatibility evidenced by cell proliferation tests, illustrating that these hydrogels are promising as dressings for wound closure, and wound healing.

Differentiation of Human Parthenogenetic Embryonic Stem Cells into Functional Hepatocyte-like Cells.

Stem cell and tissue engineering-based therapies for acute liver failure (ALF) have been limited by the lack of an optimal cell source. We aimed to determine the suitability of human parthenogenetic embryonic stem cells (hPESCs) for the development of strategies to treat ALF. We studied the ability of human parthenogenetic embryonic stem cells (hPESCs) with high whole-genome SNP homozygosity, which were obtained by natural activation during in vitro fertilization (IVF), to differentiate into functional hepatocyte-like cells in vitro by monolayer plane orientation. hPESCs were induced on a single-layer flat plate for 21 d in complete medium with the inducers activin A, FGF-4, BMP-2, HGF, OSM, DEX, and B27. Polygonal cell morphology and binuclear cells were observed after 21 d of induction by using an inverted microscope. RT-qPCR results showed that the levels of hepatocyte-specific genes such as AFP, ALB, HNF4a, CYP3A4, SLCO1B3, and ABCC2 significantly increased after induction. Immunocytochemical assay showed CK18 and Hepa expression in the induced cells. Indocyanine green (ICG) staining showed that the cells had the ability to absorb and metabolize dyes. Detection of marker proteins and urea in cell culture supernatants showed that the cells obtained after 21 d of induction had synthetic and secretory functions. The typical ultrastructure of liver cells was observed using TEM after 21 d of induction. The results indicate that naturally activated hPESCs can be induced to differentiate into hepatocellular cells by monolayer planar induction.

Indole hydrazide compound ZJQ-24 inhibits angiogenesis and induces apoptosis cell death through abrogation of AKT/mTOR pathway in hepatocellular carcinoma.

Angiogenesis and the activation of AKT/mTOR pathway are crucial for hepatocarcinoma development and progression, the activation of mTORC1/2 and relevant substrates have been confirmed in clinical hepatocarcinoma samples. Therefore, AKT/mTOR pathway represents the major targets for anti-cancer drugs development. Here, we investigated the anti-proliferative activity and mechanisms of ZJQ-24 in hepatocellular carcinoma, both in vivo and in vitro. A hepatocellular carcinoma xenograft model showed that ZJQ-24 significantly inhibited tumor growth with few side effects. MTT assays, flow cytometric analysis, Western blotting and immunohistochemistry identified that ZJQ-24 effectively suppressed hepatocellular carcinoma cell proliferation via G2/M phase arrest and caspase-dependent apoptosis but had no cytotoxic on normal cells. Furthermore, ZJQ-24 significantly blocked AKT/mTOR signaling by down-regulation of mTORC1 molecules, including phospho-p70S6K (Thr389) and phospho-4EBP-1 (Ser65, Thr37/46, Thr70) and phospho-AKT (Ser473) in HCC cells. It is very important that the ZJQ-24 did not induce the mTORC1-depdent PI3K/Akt feedback activation through JNK excitation. Moreover, ZJQ-24 inhibited the cap-dependent translation initiation by impairing the assembly of the eIF4E/eIF4G complex. Immunohistochemistry further confirmed ZJQ-24 inhibited the tumor growth through suppression of VEGF and AKT/mTOR pathways in vivo. Thus, the present study is the first to illustrate that ZJQ-24 triggers antiangiogenic activity and apoptosis via inhibiting the AKT/mTOR pathway in hepatocellular carcinoma cells, providing basic scientific evidence that ZJQ-24 shows great potential function as inhibitor of angiogenesis and tumor growth in hepatocellular carcinoma.

Efficient Definitive Endoderm Differentiation from Human Parthenogenetic Embryonic Stem Cells Induced by Activin A and Wnt3a.

OBJECTIVE: This study aimed to investigate the effects of combined activin A and Wnt3a treatment on definitive endoderm (DE) differentiation from human parthenogenetic embryonic stem cells (hPESCs). METHODS: hPESCs on human foreskin fibroblast feeder layers were induced to differentiate into DE using a combination of 50 ng/ml activin A and 25 ng/ml Wnt3a. Expression of the DE markers CXCR4, E-cadherin (ECD), Sox17, and Goosecoid (Gsc) were examined using flow cytometry and real-time quantitative PCR. RESULTS: The combination of activin A and Wnt3a significantly enhanced the percentages of CXCR4+, ECD+, Sox17+, and Gsc+ cells, culminating on day 2 of induction. This combined use promoted DE differentiation from hPESCs in vitro. CONCLUSIONS: Through the combination treatment using activin A and Wnt3a, DE differentiation from hPESCs culminated at 48 h, which can be regarded as the optimal time-point to induce differentiation of endodermal cells such as pancreatic, liver, and intestinal cells.

Ultrasensitive Magnetic Tuning of Optical Properties of Films of Cholesteric Cellulose Nanocrystals.

Chiral photonic crystals derived from the self-assembly of cellulose nanocrystals (CNCs) have found important applications in optical devices due to the capacity to adjust the chiral nematic phase under external stimulus, in particular an applied magnetic field. To date, strong magnetic fields have been required to induce an optical response in CNC films. In this work, the self-assembly of films of CNCs can be tuned by applying an ultrasmall magnetic field. The CNCs, decorated with Fe3O4 nanoparticles (Fe3O4/CNCs), were dispersed in suspensions of neat CNCs so as to alter the magnetic response of the CNCs. A subsequent process of dispersion not only prevents the clumping of the magnetic nanoparticles but also enhances the sensitivity to an applied magnetic field. A small magnetic field of 7 mT can tune the self-assembly and the microstructure of the CNCs. The pitch of the chiral structure decreased with an increase in applied magnetic field, from 302 to 206 nm, for fields from 7 to 15 mT. This phenomenon is opposite that observed for neat CNCs, in which the pitch is observed to increase with an increase in the external magnetic strength. The optical response under application of an ultrasmall magnetic field could help with theoretical research and enable more applications, such as sensors or nanotemplating agents.

Lentivirus-Mediated hFGF21 Stable Expression in Liver of Diabetic Rats Model and Its Antidiabetic Effect Observation.

The incidence of type 2 diabetes mellitus (T2DM) has been increasing annually, which is a serious threat to human health. Fibroblast growth factor 21 (FGF21) is one of the most popular targets for the treatment of diabetes because it effectively improves glycolipid metabolism. In our experiment, human FGF21 (hFGF21) was injected and stably expressed in the liver tissues of a rat T2DM model with lentivirus system. Based on clinical and histopathological examinations, islet cells were protected and liver tissue lesions were repaired for >4 months. Glucose metabolism and histopathology were controlled perfectly when hFGF21 was stably expressed in partial liver of T2DM rats. The results showed that the liver tissue cell apoptosis was reduced, the lipid droplet content was decreased, the oxidative stress indexes were improved, the glycogen content was increased, and the islet cells were increased too. Besides, insulin sensitivity and glycogen synthesis-related genes expression were increased, but cell apoptosis-related genes caspase3 and NFκB expression were decreased. The effectiveness of results suggested that injecting hFGF21 to rats liver could effectively treat T2DM.

A sensitive fluorescence assay of organophosphorus pesticides using acetylcholinesterase and copper-catalyzed click chemistry.

Organophosphorus pesticides (OPs) are widely used in agricultural fields, but exhibit high toxicity to human beings. A sensitive fluorescence assay for organophosphorus pesticides was developed using the inhibition of acetylcholinesterase (AChE) activity and the copper-catalyzed click chemical reaction. In the click reaction, two hybridized DNA probes can be ligated with copper ions, inducing a fluorescence quenching during the strand displacement reaction. AChE can hydrolyze acetylthiocholine (ATCh) to form thiocholine (TCh) which contains a thiol group. TCh will react with copper ions, blocking the click reaction and a high fluorescence signal is observed. But in the presence of OPs, the activity of AChE is inhibited, releasing a high concentration of copper ions that catalyze the click chemical reaction and resulting in decreased fluorescence signals. Taking advantage of the copper-mediated signal amplification effect, the sensitivity was improved. This assay has also been applied to detect OPs in river water samples with satisfactory results, which demonstrates that the method has great potential for practical applications in environmental protection and food safety fields.

Pb(ΙΙ) removal from water using porous hydrogel of chitosan-2D montmorillonite.

An eco-friendly chitosan-2D montmorillonite (CTS/2DMMT) hydrogel with the characteristics of high surface area, porous structure and easy separation as a new type of adsorbent was investigated. Hydrogel was prepared via self-assembling 2DMMT and CTS. 2DMMT and hydrogel were characterized by particle size analysis, SEM and AFM, respectively. The results showed the 2DMMT was well exfoliated and the porosity of hydrogel's structure could be adjusted by the CTS/2DMMT ratio. The effect of pH, adsorption kinetics and adsorption isotherm of Pb(ΙΙ) from aqueous solution onto hydrogels were investigated. Adsorption could proceed without the pH adjustment and hydrogel with a looser structure has better adsorption effectiveness. The Pseudo-first-order kinetics model and Freundlich isotherm model could fit well with the Pb(ΙΙ) adsorption process onto hydrogel. The adsorption mechanism was the ion-exchange according to the analysis of XPS and EDS.

Preparation of Montmorillonite Nanosheets through Freezing/Thawing and Ultrasonic Exfoliation.

The exfoliation of layered montmorillonite (MMT) into mono- or few-layer sheets is of significance for both fundamental studies and potential applications. In this report, exfoliated MMT nanosheets with different aspect ratios have been prepared via a new freezing/thawing-ultrasonic exfoliation method. Freezing/thawing processing can exfoliate MMT tactoids with low efficiency while virtually retaining the original lateral size. The ultrasonic method has better exfoliation efficiency but tends to damage the nanosheets. By combining them and reasonably controlling the cycle index of freezing/thawing and ultrasonic power, the MMT nanosheets with different aspect ratios have been prepared efficiently. Such a unique exfoliation method has broad applicability for layered materials to produce monolayer nanosheets on a large scale.

Overexpression of homeodomain-interacting protein kinase 2 (HIPK2) attenuates sepsis-mediated liver injury by restoring autophagy.

Sepsis is the leading cause of death in intensive care units worldwide. Autophagy has recently been shown to protect against sepsis-induced liver injury. Here, we investigated the roles of homeodomain-interacting protein kinase 2 (HIPK2) in the molecular mechanism of sepsis-induced liver injury. HIPK2 expression was reduced in sepsis-induced liver injury, and HIPK2 overexpression increased the survival rate and improved caecal ligation and puncture (CLP)-induced liver injury by reducing serum and liver aspartate transaminase (AST), alanine transaminase (ALT), and alkaline phosphatase (ALP) levels in mice with sepsis. HIPK2 overexpression significantly decreased CLP-induced release of inflammatory cytokines into the serum and attenuated oxidative stress-associated indicators in mice with CLP-induced liver injury, whereas HIPK2 knockdown produced the opposite results, suggesting that HIPK2 is a negative regulator of sepsis. Furthermore, HIPK2 overexpression inhibited lipopolysaccharide (LPS)-induced apoptosis of primary hepatocytes, increased the autophagic flux, and restored both autophagosome and autolysosome formation in the livers of CLP-induced mice by suppressing calpain signalling. Importantly, HIPK2 overexpression reduced the elevated cytosolic Ca2+ concentration in LPS-treated primary hepatocytes by interacting with calpain 1 and calmodulin. Finally, several anti-inflammatory drugs, including resveratrol, aspirin, vitamin E and ursolic acid, significantly increased the levels of the HIPK2 mRNA and protein by modulating promoter activity and the 3'-UTR stability of the HIPK2 gene. In conclusion, HIPK2 overexpression may improve sepsis-induced liver injury by restoring autophagy and thus might be a promising target for the clinical treatment of sepsis.

Toosendanin inhibits adipogenesis by activating Wnt/ß-catenin signaling.

Toosendanin (TSN), a triterpenoid extracted from Melia toosendan, has been reported to possess anti-oxidant, anti-inflammatory, anti-allergic, and anti-arthritic activities. However, its anti-adipogenic effect remains unknown. Here, we found that TSN dose-dependently attenuated lipid accumulation in preadipocytes 3T3-L1 as evidenced by Oil Red O staining. TSN also significantly downregulated mRNA and protein levels of adipocytokines (adiponectin and leptin), CCAAT/enhancer binding proteins α (C/EBP-α), peroxisome proliferator-activated receptor γ (PPAR-γ), fatty acid synthase, and acetyl-CoA carboxylase in adipocytes. To understand the mechanism, we observed that TSN effectively activated Wnt/ß-catenin pathway, in which TSN increased low density lipoprotein receptor related protein 6, disheveled 2, ß-catenin, and cyclin D1 expression levels, while it inactivated glycogen synthase kinase 3ß by enhancing its phosphorylation. Moreover, TSN reduced weight of gonadal white fat and serum triacylglycerol (TAG) content in high-fat diet (HFD)-fed mice. Interestingly, the in vivo studies also demonstrated that TSN promoted the expression of ß-catenin, but accordingly repressed C/EBP-α and PPAR-γ expression in HFD-induced mice. Overall, TSN is capable of inhibiting the lipogenesis of adipocytes by activating the Wnt/ß-catenin pathway, suggesting potential application of TSN as a natural anti-obesity agent.

miR-1224-5p Enhances Hepatic Lipogenesis by Targeting Adenosine Monophosphate-Activated Protein Kinase α1 in Male Mice.

MicroRNAs are potential therapeutic targets for metabolic diseases. Here, miR-1224-5p was highly expressed in the livers of mice fed a high-fat diet (HFD) and in obese (ob/ob) mice. To examine the potential role of miR-1224-5p, we constructed liver-specific adenoviral vectors expressing either an miR-1224-5p inhibitor sequence or miR-1224-5p mimic sequences. After tail-vein vector injection, HFD-fed mice were examined for expression of lipogenic genes. We found that miR-1224-5p inhibitors significantly attenuated hepatic lipogenesis and steatosis in HFD-fed mice, whereas miR-1224-5p mimicked promoted lipid accumulation in the liver of chow-fed C57BL/6 mice. Additional in vitro studies demonstrated that downregulation of miR-1224-5p in HepG2 and primary hepatocytes led to a reduction of cellular triglycerides after treatment with an oleic acid and palmitic acid mixture. Importantly, this study also identified adenosine monophosphate-activated protein kinase (AMPK)-α1 as a direct target of miR-1224-5p. miR-1224-5p binding to the 3' untranslated region of AMPKα1 suppressed expression of the AMPKα1 protein and its downstream molecules. Metformin, an activator of AMPK, also inhibited hepatic expression of miR-1224-5p. Together, these findings indicate that miR-1224-5p promotes hepatic lipogenesis by suppressing AMPKα1 expression and suggest that miR-1224-5p inhibitors warrant further investigation as potential therapeutic tools in the treatment of nonalcoholic fatty liver disease.