[Effects of melatonin on PBDE-47-induced abnormal autophagy and apoptosis in PC12 cells]

OBJECTIVE

To explore the effect of melatonin (MT) on 2, 2', 4, 4'-tetrabromodiphenylether (PBDE-47)-induced abnormal autophagy and apoptosis in rat adrenal medullary pheochromocytoma PC12 cells.

METHODS

PC12 cells were pretreated with a concentration gradient (12.5, 25, 50, 100, and 200 μmol/L) of melatonin for 2 h before exposure to 20 μmol/L PBDE-47 for 24 h to determine the optimal concentration of melatonin for cell treatment. In subsequent experiments, PC12 cells were treated with 0.5‰ DMSO (control group), 20 μmol/L PBDE-47, 25 μmol/L melatonin, or both PBDE-47 and melatonin. Immunofluorescence assay was used to detect the positive staining of microtubule associated protein 1 light chain 3 (LC3; a marker protein of autophagy); Western blotting was performed to determine the expression levels of the key autophagic proteins including autophagy-related protein 7 (ATG7), LC3-Ⅱ and autophagy substrate p62, and the key apoptotic proteins including active cysteine-containing aspartate specific protease-3 (active caspase-3) and cleaved poly(ADP ribose) polymerase (cleaved PARP).

RESULTS

PBDE-47 treatment significantly reduced the viability of PC12 cells (P=0.001), but pretreatment with 25 μmol/L melatonin maintained a cell viability over 80% following exposure to PBDE-47 (P=0.023). PBDE-47-treated PC12 cells showed obviously enhanced immunofluorescent staining of LC3 protein, a significantly decreased expression of ATG7 and increased expression levels of p62, LC3-Ⅱ, active caspase-3 and cleaved PARP (P < 0.001). The cells treated with both PBDE-47 and melatonin showed obviously reduced staining of LC3 protein with a signficantly increased expression level of ATG7 (P=0.034) and decreased expressions of p62 (P=0.048), LC3-Ⅱ (P=0.018), active caspase-3 (P < 0.001) and cleaved PARP (P=0.032).

CONCLUSION

PBDE-47 exposure impairs autophagy to cause autophagosome accumulation and promote apoptosis of PC12 cells. Melatonin can improve PBDE-47-induced abnormal autophagy and apoptosis and thus promote the survival of PC12 cells.

O-189 Male fertility restoration by direct transplantation of human infant testicular cells into infertile recipient mouse testis

Study question

Is colonization of human gonocytes and spermatogonial stem cells (SSCs) directly transplanted to seminiferous tubules of busulfan sterilised mice testis during an 8-week period feasible? 

Summary answer

Gonocytes and SSCs from infant boys can settle on the basal membrane and form germline stem cell colonies in the seminiferous tubules of recipient mice.

What is known already

The neonatal or immature animal provides higher populations of gonocytes and/or SSCs than adults, and the number of transplanted donor SSCs directly affects the colonization rate of the recipient testes. Along with SSC transplantation restoring the recipient’s spermatogenesis, donor gonocyte was also reported to be capable of establishing spermatogenesis in rodents.

Study design, size, duration

Transplantation of human testicular cells including gonocytes and SSCs into seminiferous tubules of infertile recipient mice. We included 10 infant testis biopsies from which single-cell suspension was transplanted individually into the seminiferous tubules of 10 immunodeficient mice. The immunodeficient mouse testes were injected with busulfan to deplete germ cells. Four weeks later, we did the xenotransplantation. Then after eight weeks, we collected all mouse testes to do further analysis.

Participants/materials, setting, methods

Testis biopsies were obtained from cryptorchid boys undergoing orchidopexy. After enzymatic digestion of the testis biopsies, dissociated single-cell suspensions were pre-labeled with a green fluorescent dye. Then the single-cell suspensions were transplanted into seminiferous tubules of the infertile recipient mice. Eight weeks later, the presence of gonocytes and SSCs was determined by immunohistochemistry and whole-mount immunofluorescence.

Main results and the role of chance

Without in vitro propagation, naturally enriched human germline stem cells settled on the basal membrane of seminiferous tubules and survived in the mouse testes at least for two months demonstrating that human gonocytes and SSCs were capable of colonizing the recipient mouse seminiferous tubules.

Limitations, reasons for caution

The study samples were from infant boys with undescended testes that were more likely to contain gonocytes. It was not possible to determine which germ-cell type at transplantation resulted in the detected gonocytes and SSC colonies after xenotransplantation. Transplantation of gonocytes may include the potential risk of stem cell-related malignancy.

Wider implications of the findings

Without in vitro propagation, male germline stem cell-based transplantation could provide a relatively safe therapeutic treatment for prepubertal boys with cryptorchidism and boys diagnosed with cancer. This method could also facilitate clinical translation.

Trial registration number

not applicable

The efficacy and safety of dupilumab in Chinese patients with moderate-to-severe atopic dermatitis: a randomized, double-blind, placebo-controlled study

BACKGROUND

Dupilumab is an antibody against interleukin 4 receptor α, used in treating atopic dermatitis (AD).

OBJECTIVES

To evaluate the efficacy and safety of dupilumab in adult Chinese patients with moderate-to-severe AD.

METHODS

In this randomized, double-blind, placebo-controlled, parallel-group, phase III study, conducted between December 2018 and February 2020, patients with AD received dupilumab (300mg) or placebo once every 2 weeks for 16 weeks, and were followed up for 12 weeks. The primary efficacy endpoint was the proportion of patients with both Investigator's Global Assessment (IGA) score of 0-1 and a reduction from baseline of ≥2 points at week 16.

RESULTS

Overall, 165 patients (mean age: 30.6 years; 71.5% male) were randomized: 82 to dupilumab and 83 to placebo. At week 16, 26.8% of patients in the dupilumab group and 4.8% of patients in the placebo group achieved the primary endpoint (difference, 22.0%; 95% confidence interval [CI], 11.37-32.65%; p<0.0001). Compared with placebo, higher proportions of patients in the dupilumab group achieved ≥75% reduction in the Eczema Area and Severity Index score (57.3% vs 14.5%; difference, 42.9%; 95% CI, 29.75-55.97%; p<0.0001) and had ≥3-point (52.4% vs 9.6%; difference, 42.8%; 95% CI, 30.26-55.34%; p<0.0001) and ≥4-point (39.0% vs 4.8%; difference, 34.2%; 95% CI, 22.69-45.72%; p<0.0001) reductions in weekly average daily peak daily pruritus numerical rating scale scores. The incidence of TEAEs during the treatment period was similar in the two groups. The incidence of conjunctivitis, allergic conjunctivitis, and injection site reaction was higher in the dupilumab group than in the placebo group.

CONCLUSIONS

In adult Chinese patients, dupilumab was effective in improving the signs and symptoms of AD and demonstrated a favorable safety profile.

[Paying attention to the fundus complications and improving the prevention and treatment of pathological myopia]

Pathological myopia, an important blinding eye disease worldwide, has caused a heavy social burden. The patients have become younger in recent years. In general, people have limited knowledge of pathological myopia. They often confuse pathological myopia with high myopia, and do not fully realize that pathological myopia is not only an ametropia disease, but also a fundus disease. Fundus complications of pathological myopia are the main causes of visual impairment, including posterior staphyloma, macular degeneration, and secondary choroidal neovascularization. All of them are related to axial length and can progress throughout the life, while the treatment is limited. At present, myopia prevention has become a national strategy, and pathological myopia is the key and difficult point in myopia prevention. The whole society should pay attention to the prevention and treatment for fundus complications of pathological myopia, take comprehensive measures, and increase scientific researches to protect the eye health of the people. (Chin J Ophthalmol, 2021, 57: 401-405).

[Research progress in relationship between vitamin D and myopia and its mechanisms]

Myopia has become an important global public health problem, especially in East Asia. Due to its high prevalence and multiple ocular complications, it is imperative to take effective measures against the development of myopia. Recent studies have shown that outdoor activity is one of the protective factors for myopia and sunlight can delay the progression of myopia. As a possible mediator between sunlight and myopia, vitamin D gradually comes into public view. Vitamin D refers to a kind of secosteroids responsible for regulating calcium and phosphate metabolism. In addition to this main function, it is also correlated with many eye diseases like diabetic retinopathy, age-related macular degeneration, glaucoma etc. This review summarizes relevant epidemiologic and genetic studies as well as possible biological mechanisms to provide theoretical reference for the plausible application of vitamin D in the prevention and therapy of myopia. (Chin J Ophthalmol, 2021, 57: 470-476).

POS0664 A MULTICENTER RANDOMIZED STUDY IN RHEUMATOID ARTHRITIS TO COMPARE IGURATIMOD, METHOTREXATE, OR COMBINATION: 52 WEEK EFFICACY AND SAFETY RESULTS OF THE SMILE TRIAL

Background:

Iguratimod (IGU) has demonstrated efficacy and safety for active rheumatoid arthritis (RA) patients in double-blind clinical trials in China and Japan as a new disease-modifying anti-rheumatic drug (DMARD). There are no studies evaluating the radiographic progression of structural joint damage of IGU for the treatment of RA using the mTSS as the primary endpoint.

Objectives:

Our study was to evaluate the efficacy and safety of IGU monotherapy and IGU combined methotrexate (MTX) compared with MTX monotherapy, including the inhibitory effects of joint destruction.

Methods:

This randomized, double-blind, parallel-controlled, multicenter study in patients with active RA who have not previously used MTX and biological DMARDs (bDMARDs) (ClinicalTrials.gov Identifier NCT01548001) was carried out in China. Patients were randomized 1:1:1 to receive IGU 25 mg twice a day (bid), MTX 10mg once a week(qw) for the first 4 weeks and 15 mg once a week(qw) for week 5 to 52, or IGU combined MTX (IGU+MTX) for 52 weeks. The primary endpoints were to assess and compare American College of Rheumatology 20% (ACR20) response and the change of modified total Sharp scoring (mTSS) score over 52 weeks (Intention-to-treat, ITT analysis). The non-inferiority test was used to analyze the difference of ACR20 response at 52 weeks between the IGU monotherapy and the MTX monotherapy arms, and the non-inferiority limit value was 10%. The difference test was used for the comparison between the IGU+MTX and MTX monotherapy arms. Two-way ANOVA was used to analyze the difference of the changes of mTSS score of each arm compared with baseline value (0 week).

Results:

A total of 895 patients were randomized to IGU 25mg bid (n =297), MTX 10-15mg qw(n=293), and IGU+MTX (n=305). Baseline characteristics were comparable between the arms (Table 1).

Table 1.

Demographic and Other Baseline Characteristics (SAS)

IGUMTXIGU+MTXNumber of Subjects297293305Age, mean (SD) years46.87(10.67)47.63(10.70)48.37(10.69)Female/male, %77.44/22.5679.18/20.8278.03/21.97Duration of RA, mean(SD) years11.67±7.1611.60±7.9811.67±7.27CRP, mean(SD) mg/L222.32±35.4720.67±26.6119.74±31.38Tender joint count, mean (SD)14.59±9.1614.83±9.3014.93±9.88Swollen joint count, mean (SD)9.81±6.639.73±7.209.51±6.22DAS28-CRP, mean (SD)5.084±0.9945.102±0.9795.103±0.956HAQ score, mean (SD)15.82±11.2515.24±10.9316.06±10.92

SAS: Safety Analysis Set; CRP: C-reactive protein;

DAS28: disease activity score; HAQ: Health Assessment Questionnaire

The study met its primary endpoints. More concretely, IGU monotherapy and IGU+MTX were found to be superior to MTX at week 52 with a higher ACR20 response of 77.44%(230/297, P=0.0019) and 77.05%(235/305, P=0.0028) versus 65.87%(193/293) (fig 1). As shown in fig 1, the structural remission (ΔmTSS≤0.5) was statistically significant for IGU monotherapy (57.4%, P=0.0308) but not for IGU+MTX arm (55%) versus MTX monotherapy (47.8%).

Overall incidence of the adverse events (AEs) leading to study discontinuation were reported in 13.8% (41/297) in IGU monotherapy arm, 11.26% (33/293) in MTX monotherapy arm and 11.51% (35/305) patients in IGU+MTX arm. The incidence of adverse drug reactions (ADR) leading to study discontinuation were 11.45% (34/297), 8.53% (25/293) and 9.21% (28/305), respectively. There was no one death and no significant difference in all the safety indicators among the three arms.

Conclusion:

Iguratimod alone or in combination with MTX demonstrated superior efficacy with acceptable safety compared to MTX for patients with active RA who have not previously used MTX bDMARDs.

Disclosure of Interests:

None declared

Hydroxytyrosol suppresses LPS-induced intrahepatic inflammatory responses via inhibition of ERK signaling pathway activation in acute liver injury

OBJECTIVE

Acute liver injury (ALI) leads to inflammatory response and tissue damage. Inflammatory activation of infiltrative macrophages plays a critical role in liver histology destruction and dysfunction. Hydroxytyrosol (3,4-dihydroxyphenil-ethanol, HT), one of the polyphenols extracted from extra virgin olive oil, currently acts as a treatment for neuroinflammatory responses, but its effect on ALI is elusive. The present study aims to examine the mechanism of HT in macrophages inflammation and evaluate treatment effect of HT on ALI.

MATERIALS AND METHODS

In vitro, the expressions of type M1/M2 macrophages biomarkers (CD11c/CD206) and cytokines (TNF-α, IL-1β, IL-6, IL-10, IL-4) following lipopolysaccharide (LPS) stimulation and HT administration were detected using immunofluorescence, quantitative real-time polymerase chain reaction (qRT-PCR), and enzyme-linked immunosorbent assay (ELISA). Mechanically, HT was used to treat cells and phosphorylation level of extracellular-signal-regulated kinase 1/2 (ERK1/2) protein in cells was analyzed using Western blotting. In murine acute liver injury, inflammatory cytokines and liver injury degree were exhibited by qRT-PCR, IHC and HE staining. Furthermore, hepatic function was exhibited via hepatic metabolic enzymes (ALT/AST) and total bilirubin (TBil) in serum.

RESULTS

It was demonstrated that HT treatment attenuated M1 macrophages and increased M2 macrophages after LPS stimulation. Furthermore, the pro-inflammatory cytokine level was descended, while an-inflammatory cytokine was increased via HT suppressing ERK pathway in macrophages. In vivo, HT reduced inflammatory level and mitigated hepatic histological injury, thus ameliorating liver function after acute liver injury.

CONCLUSIONS

HT exerts a hepatoprotective and anti-inflammation effect on acute liver injury, which restrains inflammation by inhibiting ERK pathway and regulating macrophages polarization. Moreover, HT prevents liver tissues from inflammatory injury. Therefore, HT serves as a potential implication to treat ALI through modulating inflammation of macrophages.

Long non-coding RNA NEAT1 regulates Hodgkin's lymphoma cell proliferation and invasion via miR-448 mediated regulation of DCLK1

OBJECTIVE

To explore whether long non-coding RNA nuclear enriched abundant transcript 1 (lncRNA NEAT1) could regulate Hodgkin's lymphoma (HL) cell proliferation and invasion through miR-448, which could target doublecortin like kinase 1 (DCLK1) and mediate DCLK1 expression.

PATIENTS AND METHODS

Expressions of NEAT1, miR-448 and DCLK1 were evaluated by qRT-PCR or Western blot assay. Cell Counting Kit-8 (CCK-8) and transwell assay were utilized to detect cell proliferation and invasion capability in L428 cells respectively. The target relationship between NEAT1, miR-448 and DCLK1 was confirmed by Luciferase reporter assay.

RESULTS

QRT-PCR results showed that NEAT1 expressed higher in HL tissues and cell lines than that in controls. In vitro experiments, NEAT1 downregulation could decrease cell proliferation and invasion capability in L428 cells. NEAT1 directly interacted with miR-448 and negatively regulated it. Moreover, DCLK1 was confirmed as a target of miR-448. DCLK1 expression was increased in L428 cells and positively regulated by NEAT1. NEAT1 overexpression upregulated the protein level of DCLK1 in L428 cells according to Western blot analysis. Additionally, DCLK1 overexpression could reverse the suppression on cell proliferation and invasion capability induced by NEAT1 knockdown or miR-448 overexpression.

CONCLUSIONS

NEAT1 might be contributed to HL progression by promoting cell proliferation and invasion capability via miR-448 mediated DCLK1 expression.

Towards High-Energy and Anti-Self-Discharge Zn-Ion Hybrid Supercapacitors with New Understanding of the Electrochemistry

Aqueous Zn-ion hybrid supercapacitors (ZHSs) are increasingly being studied as a novel electrochemical energy storage system with prominent electrochemical performance, high safety and low cost. Herein, high-energy and anti-self-discharge ZHSs are realized based on the fibrous carbon cathodes with hierarchically porous surface and O/N heteroatom functional groups. Hierarchically porous surface of the fabricated free-standing fibrous carbon cathodes not only provides abundant active sites for divalent ion storage, but also optimizes ion transport kinetics. Consequently, the cathodes show a high gravimetric capacity of 156 mAh g^-1, superior rate capability (79 mAh g^-1 with a very short charge/discharge time of 14 s) and exceptional cycling stability. Meanwhile, hierarchical pore structure and suitable surface functional groups of the cathodes endow ZHSs with a high energy density of 127 Wh kg^-1, a high power density of 15.3 kW kg^-1 and good anti-self-discharge performance. Mechanism investigation reveals that ZHS electrochemistry involves cation adsorption/desorption and Zn₄SO₄(OH)₆·5H₂O formation/dissolution at low voltage and anion adsorption/desorption at high voltage on carbon cathodes. The roles of these reactions in energy storage of ZHSs are elucidated. This work not only paves a way for high-performance cathode materials of ZHSs, but also provides a deeper understanding of ZHS electrochemistry.

[A Meta-analysis on association between statins and colorectal cancer]

Objective: To explore the association between statins and colorectal cancer and provide evidence for the prevention of colorectal cancer. Methods: Literatures about statins and colorectal cancer published from January 2000 to January 2020 were retrieved from CNKI, Wanfang data, PubMed and Cochrane Library database. The literatures which met the inclusion criteria were collected, and the Newcastle-Ottawa Scale and Jadad score were used to assess the studies. Meta-analysis was performed with statistical software Revman 5.0 and Stata 12.1. Results: A total of 31 studies, involving more than 1.62 million subjects, were included in the analysis. The case-control study (RR=0.93, 95%CI: 0.88-0.98), the cohort study (RR=0.75, 95%CI: 0.63-0.88) and the randomized controlled trial (RR=0.79, 95%CI: 0.65-0.97) showed moderate protective effect of statins. Using statin <5 years (RR=0.86, 95%CI: 0.76-0.96), average daily dosage ≥34 mg (RR=0.81, 95%CI: 0.66-0.98) and lipid-soluble statins (RR=0.86, 95%CI: 0.74-0.99) also had preventive effect on colorectal cancer; while lovastatin (RR=1.07, 95%CI: 1.00-1.14) increased the risk of colorectal cancer. Conclusion: Statins have protective effect on colorectal cancer.

Simultaneously Regulating Uniform Zn2+ Flux and Electron Conduction by MOF/rGO Interlayers for High-Performance Zn Anodes

Owing to the merits of low cost, high safety and environmental benignity, rechargeable aqueous Zn-based batteries (ZBs) have gained tremendous attention in recent years. Nevertheless, the poor reversibility of Zn anodes that originates from dendrite growth, surface passivation and corrosion, severely hinders the further development of ZBs. To tackle these issues, here we report a Janus separator based on a Zn-ion conductive metal-organic framework (MOF) and reduced graphene oxide (rGO), which is able to regulate uniform Zn²⁺ flux and electron conduction simultaneously during battery operation. Facilitated by the MOF/rGO bifunctional interlayers, the Zn anodes demonstrate stable plating/stripping behavior (over 500 h at 1 mA cm^-2), high Coulombic efficiency (99.2% at 2 mA cm^-2 after 100 cycles) and reduced redox barrier. Moreover, it is also found that the Zn corrosion can be effectively retarded through diminishing the potential discrepancy on Zn surface. Such a separator engineering also saliently promotes the overall performance of Zn|MnO₂ full cells, which deliver nearly 100% capacity retention after 2000 cycles at 4 A g^-1 and high power density over 10 kW kg^-1. This work provides a feasible route to the high-performance Zn anodes for ZBs.

Meishan neonatal piglets tend to have higher intestinal barrier function than crossbred neonatal piglets

Meishan pigs tend to have higher disease resistance than commercial breeds, although more studies are needed to confirm this difference. This study compared intestinal barrier function between Meishan and crossbred neonatal piglets to provide guidance for both the breeding and nutritional regulation of pigs. Six Meishan piglets and 6 Duroc × (Landrace × Yorkshire) crossbred neonatal piglets (all with normal birth weights) were obtained and allocated into the MEIS and CROSS groups, respectively. Intestinal morphology, goblet cell numbers, antioxidant enzyme activity, and cytokine gene and tight junction protein expression were assessed. The results showed that BW was lower in the MEIS group than in the CROSS group (P < 0.01). The relative lengths of the duodenum (P < 0.05), jejunum (P < 0.01) and ileum (P < 0.01) in the MEIS group were higher than those in the CROSS group. Compared with the CROSS group, the MEIS group exhibited shorter villus lengths in the duodenum and jejunum (P < 0.01), a shallower crypt depth in the ileum (P < 0.001) and denser and longer microvilli in the intestine. The numbers of GCs in the duodenum (P < 0.01) and jejunum (P < 0.001) and the activity levels of glutathione peroxidase (P < 0.05) in the jejunum and of catalase (P < 0.01) and superoxide dismutase (P < 0.01) in the ileum were higher in the MEIS group than in the CROSS group. Compared with the CROSS group, the MEIS group exhibited higher gene expression levels of interleukin (IL) 4 and interferon γ (IFNγ) in the jejunum (P < 0.05); IL2 (P < 0.05), IL4 (P < 0.01) and IFNγ (P < 0.001) in the ileum; and mucin 2 (P < 0.01) and occludin (P < 0.05) in the duodenum. In conclusion, Meishan neonatal piglets showed lower birth weights but higher intestinal barrier function than crossbred piglets.

Printable Zinc-Ion Hybrid Micro-Capacitors for Flexible Self-Powered Integrated Units

Wearable self-powered systems integrated with energy conversion and storage devices such as solar-charging power units arouse widespread concerns in scientific and industrial realms. However, their applications are hampered by the restrictions of unbefitting size matching between integrated modules, limited tolerance to the variation of input current, reliability, and safety issues. Herein, flexible solar-charging self-powered units based on printed Zn-ion hybrid micro-capacitor as the energy storage module is developed. Unique 3D micro-/nano-architecture of the biomass kelp-carbon combined with multivalent ion (Zn²⁺) storage endows the aqueous Zn-ion hybrid capacitor with high specific capacity (196.7 mAh g^-1 at 0.1 A g^-1). By employing an in-plane asymmetric printing technique, the fabricated quasi-solid-state Zn-ion hybrid micro-capacitors exhibit high rate, long life and energy density up to 8.2 μWh cm^-2. After integrating the micro-capacitor with organic solar cells, the derived self-powered system presents outstanding energy conversion/storage efficiency (η_overall = 17.8%), solar-charging cyclic stability (95% after 100 cycles), wide current tolerance, and good mechanical flexibility. Such portable, wearable, and green integrated units offer new insights into design of advanced self-powered systems toward the goal of developing highly safe, economic, stable, and long-life smart wearable electronics.

Resveratrol ameliorates high-fat diet-induced insulin resistance and fatty acid oxidation via ATM-AMPK axis in skeletal muscle

OBJECTIVE

Resveratrol (RSV) is a polyphenolic phytoalexin that exhibits diverse pharmacological actions, including its effect on the insulin resistance. However, the mechanism through which RSV improves insulin resistance is not fully understood yet. The aim of this study was to determine the mechanism through which RSV ameliorates insulin resistance in skeletal muscle of high-fat diet (HFD)-induced mouse model, as well as palmitic acid (PA) treated L6 cells, with a specific focus on the response of RSV on fatty acid oxidation.

MATERIALS AND METHODS

Male C57BL6/J mice were randomly divided into three groups: normal diet-fed mice (ND), the high-fat diet-fed mice (HFD), HFD supplemented with RSV (100 mg/kg body weight [BW]/day orally; n = 10). Fasting plasma glucose, insulin, total cholesterol, triglyceride (TG), and free fatty acid levels were determined. The intraperitoneal glucose tolerance test was used to measure blood glucose and area under the curve. The quantitative insulin sensitivity index was calculated to assess insulin resistance. Skeletal muscles were collected for histology study and protein expression measurement. L6 cells were cultured with PA and the glucose concentration in the culture medium, and the intracellular TG levels were tested. RSV, chloroquine, palmitoyltransferase and Ku-55933 were administered to differentiate L6 cells.

RESULTS

The HFD fed mice showed increased BW, hyperglycemia, and hyperlipidemia. The expressions of ataxia telangiectasia mutated (ATM), 5' adenosine monophosphate-activated protein kinase (AMPK), carnitine palmitoyltransferase 1, cytochrome oxidase subunit IV protein were significantly decreased in the skeletal muscles of HFD fed mice and PA-treated L6 cells. All these effects induced by HFD and PA were reversed by RSV treatment.

CONCLUSIONS

ATM is a key factor to improve HFD-induced lipid metabolism and insulin resistance in skeletal muscles. The effects of RSV on ameliorating HFD-induced abnormal lipid metabolism and insulin resistance mediated through ATM-AMPK pathway may due to its improvement in fatty acid oxidation efficiency and sequential reduction in ROS production in skeletal muscle. These results provide important theoretical evidence for the application of RSV in the prevention and treatment of diabetes mellitus and related metabolic diseases.

PLZF regulates apoptosis of leukemia cells by regulating AKT/Foxo3a pathway

OBJECTIVE

To explore the regulatory role of PLZF in the malignant phenotype of non-APL acute myeloid leukemia (AML) and its underlying mechanism.

MATERIALS AND METHODS

The expression level of PLZF in AML cell lines KG-1a, HL-60, OCI-AML3, THP-1 and K562 was detected by quantitative Polymerase Chain Reaction (qPCR) and Western blot, respectively. Subsequently, THP-1 cells were divided into mock group (no treatment), scramble group (transfection with scramble shRNA) and shPLZF group (transfection with shPLZF). THP-1 cell line stably expressing shPLZF was constructed, followed by determination of its transfection efficiency by qPCR and Western blot, respectively. The proliferation and colony formation of THP-1 cells were accessed using CCK-8 (cell counting kit-8) assay and colony formation assay, respectively. The apoptotic rate in THP-1 cells was determined using flow cytometry. Protein levels of apoptosis-related genes in THP-1 cells were detected by Western blot. Finally, protein levels of AKT, Foxo3a, pAKT and pFoxo3a were detected by Western blot as well.

RESULTS

Both mRNA and protein levels of PLZF were relatively high in THP-1 cells, and were selected for the following experiments. After construction of THP-1 cell line stably expressing shPLZF, proliferative rate and colony formation abilities increased in the shPLZF group compared with the mock group and the scramble group. We found a decreased apoptotic rate, downregulated Bax and upregulated Bcl-2 in the shPLZF group than those of the mock group and scramble group. Phosphorylation levels of AKT and Foxo3a increased after interference with PLZF, whereas no significant changes in total levels of AKT and Foxo3a were observed.

CONCLUSIONS

PLZF inhibits the malignant phenotype of AML by regulating the AKT/Foxo3a pathway.

KLF5 silence attenuates proliferation and epithelial-mesenchymal transition induction in Hep-2 cells through NF-κB signaling pathway

OBJECTIVE

This study aimed at exploring the role and mechanism of Krüppel-like factor 5 (KLF5) in the migration, invasion, epithelial-mesenchymal transition (EMT) induction and proliferation in laryngeal cancer human epithelial type 2 (Hep-2) cells, and to provide a new sight for the treatment of laryngeal carcinoma.

MATERIALS AND METHODS

Hep-2 cells were randomly divided into three groups: control group (Control), KLF5 siRNA group (siKLF5) and control-siRNA group (NC). The effects of KLF5 inhibition on cell proliferation and apoptosis were assessed by 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and flow cytometer, respectively. Wound healing assay and transwell invasion experiments were used to determine cell migration and invasion. Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot were used to compare the levels of KLF5, EMT-related genes E-cadherin, N-cadherin, Vimentin and Zinc finger transcription factors (Snail, Slug) expressions. The levels of nuclear transcription factor-κB (NF-κB-p65) and IκBα were also detected by Western blot.

RESULTS

Compared with the Control group, the proliferation rate of Hep-2 cells in the siKLF5 group was significantly decreased while the apoptosis rate was increased (p<0.05). Meanwhile, the migration and invasion ability of Hep-2 cells were markedly decreased (p<0.05). E-cadherin protein expression was up-regulated while Vimentin, N-cadherin, Snail, and Slug protein expression levels were downregulated in siKLF5 group (p<0.05). Silencing KLF5 could inhibit the expression of NF-κB phosphorylation at p65 and the IκBα degradation (p<0.05).

CONCLUSIONS

These results revealed that silencing KLF5 expression reduced the proliferation, migration and invasion and EMT abilities by inhibiting the NF-κB pathway in Hep-2 cells. Our results suggest that KLF5 may be a potential therapeutic target in laryngeal carcinoma.