Red blood cell membrane-coated functionalized Au nanocage as a biomimetic platform for improved MicroRNA delivery in hepatocellular carcinoma.

Dysregulation of microRNAs (miRNAs) expression is closely related to cancers and managing miRNA expression holds great promise for cancer therapy. However, their wide clinical application has been hampered by their poor stability, short half-life and non-specific biodistribution in vivo. Herein, a novel biomimetic platform designated as RHAuNCs-miRNA for improved miRNA delivery was prepared through wrapping miRNA-loaded functionalized Au nanocages (AuNCs) with red blood cell (RBC) membrane. RHAuNCs-miRNA not only successfully loaded miRNAs but also effectively protected them from enzymatic degradation. With good stability, RHAuNCs-miRNA had the characteristics of photothermal conversion and sustained release. Cellular uptake of RHAuNCs-miRNA by SMMC-7721 cells was in a time-dependent manner via clathrin- and caveolin-mediated endocytosis. The uptake of RHAuNCs-miRNAs was affected by cell types and improved by mild near infrared (NIR) laser irradiation. More importantly, RHAuNCs-miRNA exhibited a prolonged circulation time without the occurrence of accelerated blood clearance (ABC) in vivo, resulting in efficient delivery to tumor tissues. This study may demonstrate the great potential of RHAuNCs-miRNA for improved miRNAs delivery.

BrACOS5 mutations induced male sterility via impeding pollen exine formation in Chinese cabbage (Brassica rapa L. ssp. pekinensis).

KEY MESSAGE: BrACOS5 mutations led to male sterility of Chinese cabbage verified in three allelic male-sterile mutants. Chinese cabbage (Brassica rapa L. ssp. pekinensis) is one of the major vegetable crops in East Asia, and the utilization of male-sterile line is an important measure for its hybrid seed production. Herein, we isolated three allelic male-sterile mutants, msm1-1, msm1-2 and msm1-3, from an ethyl methane sulfonate (EMS) mutagenized population of Chinese cabbage double-haploid (DH) line 'FT', whose microspores were completely aborted with severely absent exine, and tapetums were abnormally developed. Genetic analyses indicated that the three male-sterile mutants belonged to allelic mutation and were triggered by the same recessive nuclear gene. MutMap-based gene mapping and kompetitive allele-specific PCR (KASP) analysis demonstrated that three different single-nucleotide polymorphisms (SNPs) of BraA09g012710.3C were responsible for the male sterility of msm1-1/2/3, respectively. BraA09g012710.3C is orthologous of Arabidopsis thaliana ACOS5 (AT1G62940), encoding an acyl-CoA synthetase in sporopollenin biosynthesis, and specifically expressed in anther, so we named BraA09g012710.3C as BrACOS5. BrACOS5 localizes to the endoplasmic reticulum (ER). Mutations of BrACOS5 resulted in decreased enzyme activities and altered fatty acid contents in msm1 anthers. As well as the transcript accumulations of putative orthologs involved in sporopollenin biosynthesis were significantly down-regulated excluding BrPKSA. These results provide strong evidence for the integral role of BrACOS5 in conserved sporopollenin biosynthesis pathway and also contribute to uncovering exine development pattern and underlying male sterility mechanism in Chinese cabbage.

Regulation of wakefulness by astrocytes in the lateral hypothalamus.

The lateral hypothalamus (LH) is an important brain region mediating sleep-wake behavior. Recent evidence has shown that astrocytes in central nervous system modulate the activity of adjacent neurons and participate in several physiological functions. However, the role of LH astrocytes in sleep-wake regulation remains unclear. Here, using synchronous recording of electroencephalogram/electromyogram in mice and calcium signals in LH astrocytes, we show that the activity of LH astrocytes is significantly increased during non-rapid eye movement (NREM) sleep-to-wake transitions and decreased during Wake-to-NREM sleep transitions. Chemogenetic activation of LH astrocytes potently promotes wakefulness and maintains long-term arousal, while chemogenetic inhibition of LH astrocytes decreases the total amount of wakefulness in mice. Moreover, by combining chemogenetics with fiber photometry, we show that activation of LH astrocytes significantly increases the calcium signals of adjacent neurons, especially among GABAergic neurons. Taken together, our results clearly illustrate that LH astrocytes are a key neural substrate regulating wakefulness and encode this behavior through surrounding GABAergic neurons. Our findings raise the possibility that overactivity of LH astrocytes may be an underlying mechanism of clinical sleep disorders.

Injectable in situ intelligent thermo-responsive hydrogel with glycyrrhetinic acid-conjugated nano graphene oxide for chemo-photothermal therapy of malignant hepatocellular tumor.

Malignant tumor is one of the major diseases with high morbidity and mortality. The purpose of this study is to prepare berberine hydrochloride (BH) in situ thermo-sensitive hydrogel based on glycyrrhetinic acid (GA) modified nano graphene oxide (NGO) (GA-BH-NGO-gel). NGO was taken as the photosensitizer, GA was taken as the target molecule, and BH was taken as the model drug. The physicochemical properties and anti-tumor activity in vivo and in vitro were also studied. This subject could provide a certain theoretical basis for the chemo-photothermal therapy combined treatment of malignant tumor. The release behavior of GA-BH-NGO-gel in vitro presented sustained and temperature-dependent drug release effect. The anti-tumor activity studies in vivo and in vitro had shown that GA-BH-NGO-gel had stronger anti-tumor activity, which could be targeting distributed to the tumor tissues. Moreover, the inhibitory effect of GA-BH-NGO-gel was enhanced when combined with 808 nm of laser irradiation. In this research, the chemo-photothermal combination therapy was applied into the tumor treatment, which may provide certain research ideas for the clinical treatment of malignant tumor.

Investigation of the genes associated with a male sterility mutant (msm) in Chinese cabbage (Brassica campestris ssp. pekinensis) using RNA-Seq.

In Chinese cabbage, hybrid seed production is performed using male sterility lines, an important approach to heterosis utilization. In this study, a stably inherited male sterile mutant msm was obtained from the 'FT'-doubled haploid line of Chinese cabbage using isolated microspore culture combined with 60Co γ-ray mutagenesis. The genetic backgrounds of 'FT' and msm were highly consistent; however, compared with wild-type 'FT', msm exhibited completely degenerated stamens and no pollen phenotype. Other characters showed no significant differences. Cytological observations revealed that stamen abortion in msm begins during the tetrad period and that tapetum cells were abnormally expanded and highly vacuolated, leading to microspore abortion. Genetic analysis indicated that the msm mutant phenotype is controlled by a single recessive nuclear gene. Comparative transcriptome analysis of 'FT' and msm flower buds using RNA-Seq technology revealed 1653 differentially expressed genes, among which, a large number associated with male sterility were detected, including 64 pollen development- and pollen tube growth-related genes, 94 pollen wall development-related genes, 11 phytohormone-related genes, and 16 transcription factor-related genes. An overwhelming majority of these genes were down-regulated in msm compared with 'FT'. Furthermore, KEGG pathway analysis indicated that a variety of carbohydrate metabolic and lipid metabolic pathways were significantly enriched, which may be related to pollen abortion. The expression patterns of 24 male sterility-related genes were analyzed using qRT-PCR. In addition, 24,476 single-nucleotide polymorphisms and 413,073 insertion-deletion events were specifically detected in msm. These results will facilitate elucidation of the regulatory mechanisms underlying male sterility in Chinese cabbage.

Gene Therapy and Photothermal Therapy of Layer-by-Layer Assembled AuNCs /PEI/miRNA/ HA Nanocomplexes.

BACKGROUND: MicroRNA (miRNA) therapy, which was widely considered to treat a series of cancer, has been confronted with numerous obstacles to being delivered into target cells because of its easy biodegradation and instability. METHODS: In this research, we successfully constructed 11-mercaptoundecanoic acid modified gold nanocages (AuNCs)/polyethyleneimine (PEI)/miRNA/hyaluronic acid (HA) complexes (abbreviated as AuNCs/PEI/miRNA/HA) using a layer-by-layer method for target-specific intracellular delivery of miRNA by HA receptor mediated endocytosis. RESULTS: The results of UV spectra, hydrodynamic diameter and zeta potential analyses confirmed the formation of AuNCs/PEI/ miRNA/HA complex with its average particle size of ca. 153 nm and surface charge of ca. -9.43 mV. Next, we evaluated the antitumor effect of the nanocomplex mediated by the combination of gene therapy and photothermal therapy (PTT) against hepatocellular carcinoma (HCC) in vitro. CONCLUSION: Our experimental results indicated that the AuNCs/PEI/miRNA/HA complex effectively delivered miRNA to the target cells and its antitumor effect was significantly enhanced by the combination of gene therapy and photothermal therapy. In addition, anti-miR-181b could promote Bel-7402 cell arrest in S phase and improve TIMP-3 mRNA expression. All these results suggested that AuNCs/PEI/miRNA/HA gene delivery system with combination of gene therapy and photothermal therapy might be exploited for HCC treatment.

Pectin methylesterase inhibitor (PMEI) family can be related to male sterility in Chinese cabbage (Brassica rapa ssp. pekinensis).

Pectin-related genes play significant roles in pollen development and pollen tube growth, and their allelic variations are one of the major reasons for the abnormal development of male gametophyte. Currently, little is known about the role of the PMEI family in male sterility of plants. In this study, 97 putative PMEI genes were identified in Brassica rapa genome. By a phylogenetic analysis, the PMEI family was divided into 10 clades with highly conserved structural characteristics. The publically available RNA-seq data on different tissues of B. rapa accession Chiifu-401-42 revealed that 23 PMEI isoforms were flower-specific genes. We created a recessive genic male sterile mutant (ftms) in Chinese cabbage. This mutant was a doubled haploid line with stable inheritance, derived from Chinese cabbage 'FT' generated through a combination of radiation mutagenesis and isolated microspore culture. The transcriptome profiles of the floral buds of ftms and its wild-type line 'FT' were determined using RNA-seq. A total of 17 PMEI genes were found to be differentially expressed; all of them were down-regulated in ftms compared to their levels in 'FT'. Consistent with the transcriptome data, all these genes were observed to be highly expressed in the floral buds of 'FT' using qRT-PCR analysis. Of these, eight genes were specifically expressed in the floral buds of 'FT'; three of these (Bra019903, Bra014099, and Bra032239) were stamen-specific genes. The results contribute to further elucidation of the regulatory mechanisms underlying male sterility in Chinese cabbage.

A54 peptide-mediated functionalized gold nanocages for targeted delivery of DOX as a combinational photothermal-chemotherapy for liver cancer.

The combination of photothermal therapy and chemotherapy (photothermal-chemotherapy) is a promising strategy for cancer therapy. Gold nanocages (AuNCs), with hollow and porous structures and unique optical properties, have become a rising star in the field of drug delivery. Here, we designed a novel targeted drug delivery system based on functionalized AuNCs and evaluated their therapeutic effects in vitro and in vivo. We then loaded doxorubicin into this promising system, designated as DHTPAuNCs consisting of hyaluronic acid-grafted and A54 peptide-targeted PEGylated AuNCs. Its formation was corroborated by ultraviolet-visible spectroscopy, transmission electron microscopy and dynamic light scattering. This delivery platform needed hyaluronidase to release encapsulated drugs, meanwhile the acidic pH and near-infrared irradiation could accelerate the release. In addition, the results of cellular uptake demonstrate that this system could bind specifically with BEL-7402 cells. In vitro, we evaluated therapeutic effects of the DHTPAuNCs in BEL-7402 cells by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-tetrazolium bromide assay. Moreover, in BEL-7402 tumor-bearing nude mice, its therapy effect in vivo was also evaluated. As expected, DHTPAuNCs exhibited excellent therapeutic effect by photothermal-chemotherapy, both in vitro and in vivo. In short, DHTPAuNCs with low toxicity showed great potential as a drug delivery system for cancer therapy.