FRI0271 IMPACT OF HLA-B27 STATUS ON CLINICAL OUTCOMES AMONG PATIENTS WITH ANKYLOSING SPONDYLITIS TREATED WITH SECUKINUMAB

Background:

Ankylosing spondylitis (AS) is strongly associated with the genetic marker HLA-B27. Approximately 80%-90% of white patients with AS express HLA-B27 compared with < 8% of the general population. In patients with AS, negative HLA-B27 status is a predictor of worse response to TNFis.1The impact of HLA-B27 status on clinical efficacy of secukinumab, a fully human monoclonal antibody that selectively inhibits IL-17A, has not been studied.

Objectives:

To analyze the impact of HLA-B27 status on clinical outcomes at Week 16 in patients with AS treated with secukinumab vs placebo.

Methods:

Patients with AS were pooled from the MEASURE 1-4 studies (NCT01358175,NCT01649375,NCT02008916, andNCT02159053) and stratified by HLA-B27 status. All trials included patients who received secukinumab 150 mg every 4 weeks with or without an initial loading dose (10 mg/kg IV at Weeks 0, 2, 4 or 150 mg SC at Weeks 0, 1, 2, and 3) or placebo control. MEASURE 3 included patients receiving secukinumab 300 mg every 4 weeks following the initial IV loading dose. Efficacy at Week 16 was determined by the proportion of patients achieving ASAS20/40, ASAS5/6, ASAS partial remission, BASDAI50, ASDAS-CRP < 2.1, ASDAS-CRP < 1.3, and improvement in Patient Global Assessment (VAS) and total spinal/back pain (VAS) scores. In MEASURE 1, 2, and 4, quality of life (QOL) was assessed at Week 16 by the SF-36 PCS, SF-36 MCS, and ASQOL. ASAS, BASDAI, and ASDAS-CRP responses were analyzed by nonresponder imputation, and all other outcomes by mixed models for repeated measures. For hypothesis generation, outcomes at Week 16 with secukinumab vs placebo within HLA-B27 strata were compared by logistic regression analysis without adjustment for multiple comparisons.

Results:

Baseline characteristics were balanced across treatment groups, although more HLA-B27+ patients than HLA-B27− patients were male (71%-73% vs 43%-50%). HLA-B27+ patients receiving any dose of secukinumab were significantly more likely to achieve ASAS, BASDAI50, and ASDAS-CRP responses vs those receiving placebo (P< .05; Figure 1). HLA-B27− patients receiving secukinumab 300 mg were significantly more likely to achieve ASAS40, ASAS partial remission (Figure 1A), and BASDAI50 (Figure 1B) responses than those receiving placebo (P< .05). Patients receiving any dose of secukinumab were more likely to achieve ASAS5/6 and ASDAS-CRP < 2.1 than those receiving placebo, regardless of HLA-B27 status (P< .05; Figure 1B). All secukinumab-treated patients experienced significant improvement in Patient Global Assessment at Week 16 vs placebo, regardless of HLA-B27 status, while only HLA-B27+ patients experienced significant reduction in total spinal/back pain vs placebo (P< .05; Figure 2A). Numerical improvements in QOL were observed in all patients receiving secukinumab 150 mg vs placebo; these reached significance for HLA-B27+ patients (Figure 2B).

Conclusion:

Secukinumab is effective in patients with AS regardless of HLA-B27 status; HLA-B27+ patients may derive increased therapeutic benefit compared with HLA-B27− patients.

Reference:

[1]Alazmi M, et al.Arthritis Care Res (Hoboken). 2018;70:1393-9.

Acknowledgments:

This study was funded by Novartis Pharmaceuticals Corporation. The authors thank Rich Karpowicz, PhD, of Health Interactions, Inc, for providing medical writing support/editorial support, which was funded by Novartis Pharmaceuticals Corporation, East Hanover, NJ, in accordance with Good Publication Practice (GPP3) guidelines (http://www.ismpp.org/gpp3).

Disclosure of Interests:

Atul Deodhar Grant/research support from: AbbVie, Eli Lilly, GSK, Novartis, Pfizer, UCB, Consultant of: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB, Speakers bureau: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB, Philip J Mease Grant/research support from: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – grant/research support, Consultant of: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – consultant, Speakers bureau: Abbott, Amgen, Biogen Idec, BMS, Eli Lilly, Genentech, Janssen, Pfizer, UCB – speakers bureau, Denis Poddubnyy Grant/research support from: AbbVie, MSD, Novartis, and Pfizer, Consultant of: AbbVie, Bristol-Myers Squibb, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB, Renato Calheiros Shareholder of: Novartis, Employee of: Novartis, Xiangyi Meng Shareholder of: Novartis, Employee of: Novartis, Vibeke Strand Consultant of: AbbVie, Amgen, Biogen, Celltrion, Consortium of Rheumatology Researchers of North America, Crescendo Bioscience, Eli Lilly, Genentech/Roche, GlaxoSmithKline, Hospira, Janssen, Merck, Novartis, Pfizer, Regeneron Pharmaceuticals, Inc., Sanofi, UCB, Marina Magrey Grant/research support from: AbbVie, Amgen, and UCB, Consultant of: Eli Lilly and Novartis

THU0397 SYMPTOMS OF PERIPHERAL ARTHRITIS ARE SIGNIFICANTLY IMPROVED IN PATIENTS WITH ANKYLOSING SPONDYLITIS TREATED WITH SECUKINUMAB

Background:

Ankylosing spondylitis (AS) is a chronic inflammatory disease of the axial skeleton associated with pain, stiffness, and disability.1Up to 66% of patients (pts) with AS may also have peripheral involvement, including swollen and tender joints (STJs),2,3which are associated with worse overall disease activity.4A previous analysis showed that secukinumab, a selective inhibitor of interleukin 17A, led to significant improvements in efficacy outcomes vs placebo, regardless of peripheral joint involvement.3However, the effect of secukinumab on symptoms of peripheral arthritis in pts with AS was not assessed.

Objectives:

The objective of this analysis was to assess changes in peripheral symptoms in pts with AS treated with secukinumab vs placebo.

Methods:

Data from pts with active AS and peripheral symptoms who were enrolled in MEASURE 1 (NCT01358175), 2 (NCT01649375), 3 (NCT02008916), and 4 (NCT02159053) were pooled in this post hoc, hypothesis-generating analysis. No adjustments for multiple comparisons were made. Pts with peripheral symptoms were identified by the presence of STJs, based on 44-joint counts at baseline (BL). Pts received subcutaneous (SC) secukinumab every 4 weeks at doses of 300 mg with an intravenous (IV) loading dose (MEASURE 3 only), 150 mg with an IV or SC loading dose, or placebo. Treatment response through Week 16 was assessed based on the proportions of pts who achieved improvements of 20%, 50%, 70%, or 100% in the number of swollen and number of tender joints and improvements in the BASDAI score for question 3 and Patient Global Assessment (PGA). Changes in the number of swollen and number of tender joints were assessed in pts with swollen or tender joints at BL, respectively.

Results:

This pooled analysis included 560 pts with AS and STJs at BL (Table). At Week 16, treatment with secukinumab led to significantly greater proportions of pts achieving reductions in the number of swollen (Fig 1A) or tender (Fig 1B) joints compared with placebo; the treatment effect was more pronounced in reduction of swollen joints. Furthermore, a greater proportion of secukinumab-treated pts achieved complete resolution of swollen or tender joints vs placebo (Fig 1). Secukinumab also led to significant improvements in peripheral pain/swelling (Fig 2A) and disease activity (Fig 2B) vs placebo, as assessed using BASDAI question 3 and the PGA, respectively.

Table.

Patient Characteristics at Baseline

SecukinumabPlacebo (n = 252)300 mg (n = 52)150 mg (n = 256)Age, mean, y43.643.744.9Time since diagnosis, mean, y5.67.27.3Male, %63.562.157.5PGA of Disease Activity, mean, mm73.471.770.1BASDAI question 3, mean6.36.66.4Swollen 44-joint count, mean1.92.62.5Tender 44-joint count, mean7.17.87.9

Conclusion:

In parallel with its previously reported efficacy in axial symptoms,3secukinumab led to significant improvements in symptoms of peripheral arthritis in pts with AS. Significant improvements were seen in both tender and swollen joints.

References:

[1]Braun J, Sieper J.Lancet. 2007;369:1379-1390.

[2]de Winter JJ, et al.Arthritis Res Ther. 2016;18:196.

[3]Mease P, et al.Arthritis Rheumatol. 2019;71(suppl 10):1553.

[4]de Winter JJ, et al.RMD Open. 2019;5:e000802.

Acknowledgments:

This study was funded by Novartis Pharmaceuticals Corporation, East Hanover, NJ. The authors thank Amos Race, PhD, of ArticulateScience LLC, Hamilton, NJ, USA, for providing medical writing/editorial support, which was funded by Novartis Pharmaceuticals Corporation, East Hanover, NJ, USA, in accordance with Good Publication Practice (GPP3) guidelines (http://www.ismpp.org/gpp3).

Disclosure of Interests:

Philip J Mease Grant/research support from: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – grant/research support, Consultant of: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – consultant, Speakers bureau: Abbott, Amgen, Biogen Idec, BMS, Eli Lilly, Genentech, Janssen, Pfizer, UCB – speakers bureau, Atul Deodhar Grant/research support from: AbbVie, Eli Lilly, GSK, Novartis, Pfizer, UCB, Consultant of: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB, Speakers bureau: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB, Renato Calheiros Shareholder of: Novartis, Employee of: Novartis, Xiangyi Meng Shareholder of: Novartis, Employee of: Novartis, Todd Fox Shareholder of: Novartis, Employee of: Novartis, Xenofon Baraliakos Grant/research support from: Grant/research support from: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Consultant of: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Speakers bureau: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen

Transcriptional regulation of heat shock protein 70 genes by class I histone deacetylases in the red flour beetle, Tribolium castaneum

The regulatory function of histone acetylation in the expression of genes encoding heat shock proteins (Hsps) has been documented in Drosophila melanogaster; however, knowledge of the role of acetylation in modulating Hsps in other insect pests is limited. In this study, two full-length cDNAs encoding inducible Hsp70 (designated TcHsp70) and heat shock cognate 70 (TcHsc70) were isolated and characterized in the red flour beetle, Tribolium castaneum. TcHsp70 and TcHsc70 cDNAs were 2256 and 2132 bp and encoded 1941- and 1893-bp open reading frames, respectively. The deduced TcHsp70 and TcHsc70 proteins contained 646 and 630 amino acids, respectively, and contained sequences typical of the Hsp70 family, including the EEVD motif for cytoplasmic localization. Expression patterns after heat shock indicated that TcHsp70 was strongly heat-inducible, whereas the expression level of TcHsc70 remained unchanged under heat shock. RNA interference-mediated knock-down of three genes encoding class I histone deacetylases differentially influenced both basal and heat shock inducible expression of TcHsp70 and TcHsc70, suggesting the involvement of histone acetylation in epigenetic regulation of Hsp70 transcription in T. castaneum.

Inhibition of microRNA-875-5p promotes radioiodine uptake in poorly differentiated thyroid carcinoma cells by upregulating sodium-iodide symporter

BACKGROUND AND AIM

Poorly differentiated thyroid carcinoma (PDTC) is an endocrine malignancy that is challenging to treat due to its limited radioiodine uptake. microRNAs (miRNAs or miRs) have been shown to be useful in treating many types of tumors, including PDTC. This study aims to evaluate the potential effect of miR-875-5p on the radioiodine uptake of PDTC and to clarify the underlying mechanisms.

METHODS

Expression of miR-875-5p and sodium-iodide symporter (NIS) in tissues and cell lines was determined using RT-qPCR. The binding relationship between miR-875-5p and NIS was predicted through in silico analysis and verified by dual-luciferase reporter gene assay. A series of miR-875-5p mimic, miR-875-5p inhibitor, shRNA against NIS, and overexpressed NIS plasmids were introduced into PDTC cells. We then evaluated the cell viability, colony formation, apoptosis, and radioiodine uptake of each PDTC sample via CCK-8 assay, clonogenic assay, flow cytometry, and γ counter, respectively.

RESULTS

miR-875-5p was found to be highly expressed, but NIS was poorly expressed in DTC tissues and PDTC cell lines. NIS was verified to be a target gene of miR-875-5p. Upregulation of miR-875-5p was found to induce PDTC cell proliferation, and reduce apoptosis and radioiodine uptake in vitro through down-regulation of NIS. In an in vivo orthotopic model, the enhancement of miR-875-5p led to the reduction of NIS expression and radioiodine uptake in the thyroid tumors.

CONCLUSIONS

Altogether, the findings of the current study suggest that down-regulated miR-875-5p expression could promote its target gene NIS to increase radioiodine uptake in PDTC, constituting a preventive strategy against PDTC.

Fractionation analysis and health risk assessment of heavy metals in six traditional Chinese medicines

Traditional Chinese medicines (TCMs) are widely used to treat various diseases in China and some countries, and TCM products are becoming increasingly available and popular worldwide. But TCMs are facing the challenge of heavy metal pollution. In this work, we examined the total contents and fractionations of Pb, Cd, Hg, and Cu in six TCMs (Angelicae Sinensis Radix (ASR), Chuanxiong Rhizoma (CR), Polygonati Rhizoma (PR), Astragali Radix (AR), Carthami Flos (CF), and Paeoniae Radix Rubra (PRR)) and evaluated the health risk of four heavy metals in these TCMs. The results showed that Cd, Pb, and Cu contents were considerably high and the amount of Cd in six TCMs, Pb in CR, ASR, AR, and CF, and Hg in ASR, PR, and PRR exceeded the limit values. The predominant fractions of Pb, Cd, and Cu were exchangeable and carbonate fractions in six TCMs; Hg mainly existed in organic and residual fractions. The average daily intake dose (ADD) and target hazard quotient (THQ) of Pb based on total content and total THQ of four heavy metals based on bioaccessible fractions in AR and PRR exceeded the safety guideline. These results indicated that the potential health risk could occur by taking these TCMs.

PRDX2 plays an oncogenic role in esophageal squamous cell carcinoma via Wnt/β-catenin and AKT pathways

PURPOSE

To investigate the role of PRDX2 in esophageal carcinoma (ESCA).

METHODS

The expression of PRDX2 was detected in ESCA tissues. And PRDX2 expression in two ESCA cell lines was knocked down. Cell proliferation, metastasis and invasion were detected in these cells.

RESULTS

Here, we found that PRDX2 expression was significantly increased in ESCA tissues and was associated with a poor prognosis in ESCA patients. In addition, PRDX2 expression was significantly associated with pathological grading, infiltration degree and 5-year survival time in ESCA patients. Next, we knocked down PRDX2 expression by PRDX2-shRNA transfection in two ESCA cell lines, Eca-109 and TE-1. Proliferation analysis indicated that in vitro PRDX2 knockdown decreased growth and clone formation of ESCA cells. Scratch and transwell assays indicated that cell migration and invasion were significantly inhibited by PRDX2 knockdown. In addition, PRDX2 knockdown inhibited cell cycle of ESCA cells and down-regulated Cyclin D1-CDK4/6. Moreover, PRDX2 knockdown regulated proteins involved in mitochondrial-dependent apoptosis, including increased Bax and Caspase9/3 and decreased Bcl2. Mechanism investigation indicated that PRDX2 knockdown led to inactivation of Wnt/β-catenin and AKT pathways.

CONCLUSIONS

Our data suggest that PRDX2 may function as an oncogene in the development of ESCA via regulating Wnt/β-catenin and AKT pathways. Our study fills a gap in the understanding of the role of PRDX2 in ESCA and provides a potential target for ESCA treatment.

Impaired geometry, volumetric density, and microstructure of cortical and trabecular bone assessed by HR-pQCT in both sporadic and MEN1-related primary hyperparathyroidism

This study evaluated bone features of PHPT using HR-pQCT. The results showed both cortical and trabecular bones were significantly impaired in PHPT patients. Male and female PHPT patients suffered similar damages in bone. HR-pQCT indices were not observed to differ in MEN1 and sporadic PHPT patients.

INTRODUCTION

High-resolution peripheral quantitative CT is a novel imaging technique used to separately assess trabecular and cortical bone status of the radius and tibia in vivo. Using HR-pQCT, we aimed to evaluate bone features of primary hyperparathyroidism patients in a Chinese population and reveal similarities and differences in bone features in multiple endocrine neoplasia type 1-related PHPT and sporadic PHPT patients in the Chinese population.

METHODS

A case-control study was designed. In 58 PHPT patients and 58 sex- and age-matched healthy controls, the distal radius and tibia were scanned using HR-pQCT. Areal bone mineral density (aBMD) was also determined in PHPT patients using dual-energy X-ray absorptiometry (DXA).

RESULTS

In comparison with controls, PHPT patients were observed to exhibit reduced volumetric BMD at the cortical and trabecular compartments, thinner cortices, and more widely spaced trabeculae. Significant differences were still observed when comparing data of female and male patients with age-matched controls separately. MHPT patients (n = 11) were found to have lower aBMD Z-scores in the lumbar spine, trochanteric region, and total hip compared with sporadic PHPT patients (n = 47), while no differences were observed in HR-pQCT indices between the two groups. In multiple linear regression models, no significant correlations were identified between PTH and HR-pQCT indices. However, height was found to positively correlate with HR-pQCT-derived trabecular indices at both the radius and tibia.

CONCLUSIONS

PHPT affects geometry, volumetric density, and microstructure in both the cortical and trabecular bones in both male and female Chinese patients. MHPT patients were observed to have reduced aBMD as determined by DXA in the lumbar spine and hip in comparison with sporadic PHPT patients. However, HR-pQCT indices were not observed to differ.

Isolation and characterization of Salmonella in pork samples collected from retail and wholesale markets in each season from 2016 to 2018 in Wuhan, China

AIMS

To investigate the prevalence and characteristics of Salmonella in pork on sale in Wuhan, Central China.

METHODS AND RESULTS

A total of 4744 pork samples were collected from retail or wholesale markets in each season from 2016 to 2018. The samples showed an overall Salmonella prevalence of 19·54% (927/4744), among which the samples collected in 2017 (21·67%, 428/1975) possessed a significantly higher prevalence than those collected in 2016 (18·61%, 209/1123) (P = 0·047) or 2018 (17·51%, 290/1656) (P = 0·002), and the samples collected in winter showed the lowest prevalence (15·86%, 177/1116). The Salmonella prevalence was significantly higher among samples from retail markets (25·68%, 283/1102) than wholesale markets (17·68%, 644/3642) (P = 0·000). Antimicrobial resistance of 922 Salmonella strains was tested by determining the minimal inhibitory concentrations using a broth microdilution method. The strains revealed that 98·92% (912/922) were resistant to at least one of the antimicrobial agents, and 80·04% (738/922) were resistant to three or more antimicrobials (MDR). Resistance to sulfamethoxazole/trimethoprim (89·91%), tetracycline (87·20%) and ampicillin (71·69%) was predominant. The proportion of MDR strains in 2017 (93·62%, 396/423) was significantly higher than that in 2016 (63·16%, 132/209) (P = 0·000) or 2018 (69·66%, 202/290) (P = 0·000). No significant difference was observed in the proportions of MDR strains between wholesale markets (76·07%, 213/280) and retail markets (80·53%, 517/642) (P = 0·075). Multi-locus sequence typing for 554 of the isolates revealed 20 different sequence types (STs), among which ST40 (38·27%, 212/554), ST34 (18·41%, 102/554) and ST469 (14·46%, 79/554) were dominant.

CONCLUSIONS

A high risk of Salmonella prevalence and antimicrobial resistance was observed in pork in Wuhan. The risk varies between different sampling years, seasons and market types.

SIGNIFICANCE AND IMPACT OF THE STUDY

Providing baseline data on Salmonella contamination in pork on sale in Central China.

Aβ1-42 regulates astrocytes through JNK/AP-1 pathway

OBJECTIVE

In Alzheimer's disease (AD), astrocytes are generally found in the surrounding of senile plaques participating in the production of phagocytosis and the removal of toxic compounds such as Aβ. This study aimed at investigating the effect of Aβ1-42 on astrocytes.

MATERIALS AND METHODS

Cellular viability of primary cultured astrocytes was analyzed using CCK-8 assay. Quantitative Real-time PCR was used to assess the mRNA expression of JNK and AP-1. The proteins of JNK/AP-1 pathway were investigated using Western blot.

RESULTS

Our findings showed that Aβ1-42 inhibited cell viability and promoted apoptosis in astrocytes in primary culture. Additionally, Aβ1-42 increased the mRNA expression level of AP-1, but had no effect on the expression of JNK. Furthermore, Aβ1-42 increased the protein expression of p-JNK, p-c-jun and Fra-1 and the ratio of p-c-jun/c-jun and p-JNK/JNK.

CONCLUSIONS

We showed that Aβ1-42 promoted cell apoptosis in astrocytes in primary culture. Furthermore, Aβ1-42 activated JNK/AP-1 pathway through promoting the phosphorylation of JNK, c-jun and Fra-1 expression, then inducing cell apoptosis.

Treatment of primary hepatic carcinoma through ultrasound-guided microwave ablation

Objective

To study the clinical effect of ultrasound-guided microwave ablation on primary hepatic carcinoma.

Method

The subjects comprised 94 patients with primary hepatic carcinoma who were admitted to our hospital between August 2014 and November 2016. They were divided into two groups in accordance with a random-number table. The control (n = 47) and study (n = 47) groups received conventional surgical excision and ultrasound-guided microwave ablation, respectively. The operation duration, clinical effect, complication occurrence rates, and hepatic functions of the two groups were compared.

Results

The control group exhibited longer duration of operation and length of stay but significantly lower quantities of intraoperative bleeding and blood transfusion (P < 0.05) than the study group. The study group demonstrated significantly higher (P < 0.05) effective rate of treatment but significantly lower (P < 0.05) occurrence rate of complications than the control group. The study group exhibited significantly higher (P < 0.05) albumin and total bilirubin levels but significantly lower alanine aminotransferase and aspartate transaminase levels than the control group. No difference was observed in prothrombin time between the two groups (P > 0.05).

Conclusion

Ultrasound-guided microwave ablation treatment offers the advantages of minor injury and low complication occurrence rates. Moreover, it is associated with faster postoperative recovery and improved hepatic function. Thus, it is worthy as a clinical option and must be promoted and applied.

P5399microRNA-486 mediates exercise-induced cardiac growth and prevents cardiac ischemia-reperfusion injury

Background

Molecules mediating exercise-induced physiological cardiac growth may be beneficial to prevent cardiac injury and remodeling. MicroRNA-486 (miR-486) is a muscle-enriched microRNA which was found to be increased in exercised heart. However, the role of miR-486 in exercise-induced cardiac growth is largely unknown.

Purpose

We aimed to study the function of miR-486 in exercise-induced cardiac growth, and to investigate its potential role in protection against cardiac ischemia/reperfusion (I/R) injury.

Methods

Male C57BL/6 adult mice were subjected to 3-week swimming exercise to induce physiological cardiac growth. Knockdown of miR-486 was performed by intramyocardial injection of miR-486 sponge to evaluate the role of miR-486 in exercise-induced cardiac growth. Moreover, intramyocardial injection of miR-486 overexpression lentivirus was performed to investigate whether miR-486 could reduce infarct size in mice suffered from acute I/R injury (30 min ligation and 24 hr reperfusion of left anterior descending coronary artery). Meanwhile, the functional role of miR-486 was evaluated in neonatal rat cardiomyocytes (NRCMs) treated with oxygen glucose deprivation/reperfusion (OGDR) using Tunel staining. Finally, function-rescue assays were performed to identify target genes of miR-486.

Results

Exercise significantly upregulated miR-486 in the heart, which was reduced by intramyocardial injection of miR-486 sponge. Exercise induced-cardiac growth was abolished in mice with intramyocardial injection of miR-486 sponge, as evidenced by reduced heart weight/body weight ratio and heart weight/tibia length ratio compared to control exercised-mice, suggesting a potential role of miR-486 in mediating exercise-induced cardiac growth. Meanwhile, we found that intramyocardial injection of miR-486 overexpression lentivirus was able to reduce the infarct size as determined by TTC staining. Moreover, in OGDR-induced apoptosis of NRCMs, miR-486 mimics was able to reduce cardiomyocyte apoptosis, while miR-486 inhibitor performed the opposite. Finally, PTEN and FoxO1 were identified as target genes of miR-486 in the control of cardiomyocyte apoptosis.

Conclusions

miR-486 mediates exercise-induced cardiac growth and protects against cardiac I/R injury. Increasing miR-486 might serve as a potential target to reduce myocardial apoptosis upon I/R injury.

Acknowledgement/Funding

This work was supported by the grants from National Natural Science Foundation of China 81722008, 91639101 and 81570362 to JJ Xiao, 81770401 to Y Bei

Litter quality and microtopography as key drivers to topsoil properties and understorey plant diversity in ancient broadleaved forests on decalcified marl

In forest ecosystems, litter quality is a major driver for soil and understorey characteristics, but elevation, microtopography and subsoil properties may also be important. We tested the importance of each factor in two ancient mixed forests on decalcified marl, dominated by trees with different litter quality such as European hornbeam, with high-palatable litter, and beech, with low-palatable litter. We mapped elevation, differences in local height (microtopography), tree distribution and understorey cover on slopes ranging from crest to bottom, and sampled 200 7 × 7 m grid cells for characteristics of litter input, understorey, topsoil and subsoil. In both forests, elevation decreased gradually, but microtopography showed irregular patterns of depressions and mounds of a few cm below or above average local height. Tree distribution was not affected by elevation or subsoil properties, but clearly by microtopography. Adult beech was abundant on local mounds, while hornbeam was more common in local depressions. Topsoil and understorey characteristics were mainly affected by litter quality (tree species dominance) and microtopography. Litter quality had separate effects from microtopography, but could reinforce this. High litter quality (hornbeam) and low local height both led to high earthworm activity, low litter mass, high erosion, impermeable clay layers close to the surface, high pH, high soil moisture and high diversity of the understorey. Low litter quality (beech) and high local height both led to low earthworm activity, high litter mass, low erosion, low pH, low soil moisture and low plant diversity. Beech and hornbeam may act as ecosystem engineers, which change habitat conditions and local hydrology, and make habitats more suitable to themselves, and/or unsuitable to the other. However, they also increased spatial complexity of the forest and length of the habitat gradient. This may increase forest biodiversity as a whole, but also resilience to prolonged wet or dry periods.

Speciation analysis and dynamic absorption characteristics of heavy metals and deleterious element during growing period of Chinese peony

The heavy metals and deleterious element (Pd, Cd, Cu, As, and Hg) in Chinese peony (Paeonia lactiflora Pall.) were determined by Tessier's sequence extraction method. Pb mainly existed in carbonate fraction. The main fraction of Cd in different tissues and different month is quite different. Cu mainly exists as exchangeable carbonate fractions. Five forms of Hg all exist in leaf, stem, and root. The total absorbable fraction of Pd, Cd, Cu, As, and Hg was different in different tissues. The total content of heavy metals can migrate from different tissues and the content of different speciation of heavy metal also can change during the growing period of plants. The results showed that different parts of plants and different elements resulted in different distribution and mobility. Base on this, it is more scientific and reasonable to clarify the migration and enrichment and to analyses the speciation of heavy metals during growing period of plant medicine. It is more scientific and reasonable to clarify the migration and enrichment, and to analyses the speciation of heavy metals during growing period of plant medicine.