HuR-positive stress granules: Potential targets for age-related osteoporosis.

Aging impairs osteoblast function and bone turnover, resulting in age-related bone degeneration. Stress granules (SGs) are membrane-less organelles that assemble in response to stress via the recruitment of RNA-binding proteins (RBPs), and have emerged as a novel mechanism in age-related diseases. Here, we identified HuR as a bone-related RBP that aggregated into SGs and facilitated osteogenesis during aging. HuR-positive SG formation increased during osteoblast differentiation, and HuR overexpression mitigated the reduction in SG formation observed in senescent osteoblasts. Moreover, HuR positively regulated the mRNA stability and expression of its target ß-catenin by binding and recruiting ß-catenin into SGs. As a potential therapeutic target, HuR activator apigenin (API) enhanced its expression and thus aided osteoblasts differentiation. API treatment increased HuR nuclear export, enhanced the recruitment of ß-catenin into HuR-positive SGs, facilitated ß-catenin nuclear translocation, and contributed osteogenesis. Our findings highlight the roles of HuR and its SGs in promoting osteogenesis during skeletal aging and lay the groundwork for novel therapeutic strategies against age-related skeletal disorders.

MiR-12200-5p Targets Multiple Members of Wnt Signaling Pathway to Inhibit Osteoblast Differentiation and Bone Formation.

BACKGROUND: Osteoporosis is widespread and has become an emerging problem in the elderly. MicroRNAs could affect osteoblast differentiation and further regulate the occurrence of osteoporosis by targeting osteogenic differentiation signaling pathways. Our screening study found that miR-12200-5p simultaneously targeted six important factors within the Wnt signaling pathway (Apc, Tcf4, Tcf7, Wnt3a, Wnt5a, and Lrp6), indicating that miR-12200-5p might function as a strong regulator of this pathway. Since the Wnt pathway exists as one of the most essential pathways for osteogenic differentiation, miR-12200-5p may have an important role in the development of osteoporosis. OBJECTIVE: This study intended to explore the regulatory role and corresponding mechanism of miR-12200-5p in osteoblast differentiation. METHODS: We investigated the differentiation of osteoblast after the treatments of miR-12200-5p mimic and inhibitor. The interactions between miR-12200-5p and its target genes were also detected. Furthermore, the rescue effect of miR-12200-5p inhibitor on osteoporosis was evaluated using an ovariectomized osteoporosis mouse model. RESULTS: MiR-12200-5p significantly inhibited osteoblast differentiation, and bound with the 3'-UTR sequences of its target genes (Apc, Tcf4, Tcf7, Wnt3a, Wnt5a, and Lrp6) to reduce the expressions of these genes. The inhibition of miR-12200-5p would almost fully alleviate postmenopausal osteoporosis. CONCLUSION: MiR-12200-5p could strongly repress osteoblast differentiation and bone formation by targeting multiple members of the Wnt signaling pathway simultaneously. The study supplemented the theoretical and experimental basis for researching the mechanism of osteogenic differentiation and inspired the development of novel therapeutic strategies for osteoporosis.

A lipid-polymer hybrid nanoparticle (LPN)-loaded dissolving microneedle patch for promoting hair regrowth by transdermal miR-218 delivery.

Alopecia is the most common multifactorial hair loss disorder, affecting almost 50% of the population and even having a serious psychological impact on the patients. miR-218 has therapeutic potential for alopecia since it can activate the Wnt/ß-catenin channel by down-regulating SFRP2, which is a key channel in hair follicle cycle transformation for hair regrowth. Although miR-218 has the potential to treat this disease, several barrier properties of the skin challenge miRNA's delivery to the target location, such as passing through the corneum and resistant enzymatic degradation. To address these challenges, we evaluated a device that combined the use of hyaluronic acid (HA)-based dissolving microneedle (MN) to enhance corneum permeability with the lipid polymer hybrid nanoparticles (LPNs) as a miRNA delivery carrier to protect miR-218 from degradation. The MN patches could promote LPNs/miR-218 diffusing in the dermis region, and significantly increase the bioavailability of miR-218. Furthermore, in the shaved mouse model, the MN patches showed higher efficacy in promoting hair growth than the topical smear treatment, while avoiding the safety concern. This work established a novel and effective combination device with MN and LPNs that can be used for localized transdermal miRNA delivery to promote hair regrowth.

Transfer RNAs-derived small RNAs and their application potential in multiple diseases.

The role of tRNAs is best known as adapter components of translational machinery. According to the central dogma of molecular biology, DNA is transcribed to RNA and in turn is translated into proteins, in which tRNA outstands by its role of the cellular courier. Recent studies have led to the revision of the canonical function of transfer RNAs (tRNAs), which indicates that tRNAs also serve as a source for short non-coding RNAs called tRNA-derived small RNAs (tsRNAs). tsRNAs play key roles in cellular processes by modulating complicated regulatory networks beyond translation and are widely involved in multiple diseases. Herein, the biogenesis and classification of tsRNAs were firstly clarified. tsRNAs are generated from pre-tRNAs or mature tRNAs and are classified into tRNA-derived fragments (tRFs) and tRNA halves (tiRNA). The tRFs include five types according to the incision loci: tRF-1, tRF-2, tRF-3, tRF-5 and i-tRF which contain 3' tiRNA and 5' tiRNA. The functions of tsRNAs and their regulation mechanisms involved in disease processes are systematically summarized as well. The mechanisms can elaborate on the specific regulation of tsRNAs. In conclusion, the current research suggests that tsRNAs are promising targets for modulating pathological processes, such as breast cancer, ischemic stroke, respiratory syncytial virus, osteoporosis and so on, and maintain vital clinical implications in diagnosis and therapeutics of various diseases.

Bergamottin promotes osteoblast differentiation and bone formation via activating the Wnt/ß-catenin signaling pathway.

Osteoporosis is one of the most common bone disorders that seriously affect the health and life quality of elderly individuals. Reduced osteoblast differentiation and bone formation lead to changes in bone volume and microarchitecture, leaving the bones vulnerable to fracture. Bergamottin (BM) is a natural compound derived from various citrus fruits and possesses multiple biological activities including anti-adipogenesis function. This study aimed to evaluate the effects of BM on osteoblast differentiation and its potential anti-osteoporosis capacity, as well as to explore the underlying mechanism. We demonstrated that BM, as a positive regulator for osteogenesis, significantly promoted osteoblast differentiation and bone formation. Mechanically, BM activated the Wnt/ß-catenin signaling pathway and promoted the nuclear translocation of ß-catenin. In addition, BM dramatically upregulated the expression of ß-catenin, enhanced the transcriptional activation of T cell factor 7 (TCF7), and increased the expression of Runt-related transcription factor 2 (Runx2). Taken together, this study revealed that BM enhanced osteoblast differentiation and attenuated ovariectomy (OVX)-induced bone loss, possessing the potential to be developed into a food ingredient or supplement for preventing osteoporosis.

Evaluation of the Low Inclusion of Full-Fatted Hermetia illucens Larvae Meal for Layer Chickens: Growth Performance, Nutrient Digestibility, and Gut Health.

Substitution of feed protein source with defatted black soldier fly larvae meal (BSFM) has been evaluated intensively in poultry, but information about full-fatted BSFM is still very limited. The aim of the present study was to investigate the effect of dietary low inclusion of full-fatted BSFM on the growth performance, plasma antioxidant ability, nutrient digestibility, and gut health of layer chickens during 1-42 days of age. A total of 480 female 1-day-old Hy-Line Brown chickens were divided into four dietary treatments, with the inclusion of 0, 3, 6, and 9% of full-fatted BSFM. Each treatment included six replicates and 20 birds per replicate. As dietary full-fatted BSFM inclusion levels increased, there was a quadratic increase in final weight and average daily gain and a quadratic decrease in feed/gain ratio. Dietary full-fatted BSFM inclusion levels increased the digestibility of crude protein and ether extract quadratically as well as ileum mucosal sIgA concentration linearly, but these had no effect on intestinal morphology. Additionally, an increase in dietary full-fatted BSFM inclusion levels resulted in a linear increase in glutathione peroxidase and total superoxide dismutase activities and a linear decrease in malondialdehyde content in plasma. The encouraging results of the improvement of growth performance, nutrient digestibility, antioxidant ability, and gut health parameters suggested that partially full-fatted BSFM inclusion can be suitable protein ingredients for layer chickens' diets at the starter period.

New insight into the molecular basis of Fe (III) stress responses of Procambarus clarkii by transcriptome analysis.

Iron in excess can have toxic effects on living organisms. In China, the freshwater crayfish Procambarus clarkii is a source of aquatic food with high-quality protein and has significant commercial value. P. clarkii shows oxidative stress on exposure to heavy metals, and antioxidant enzymes, such as ubiquitination enzymes and proteasomes, play important roles in oxidative stress. To understand the antioxidant defense system of P. clarkii, we analyzed the hepatopancreas transcriptomes of P. clarkii after stimulation with FeCl3. In total, 5199 differentially expressed genes (DEGs) were identified (2747 upregulated and 2452 downregulated). GO analysis revealed that these DEGs belonged to 16 cellular component, 16 molecular function, and 19 biological process subcategories. A total of 1069 DEGs were classified into 25 categories by using COG. Some antioxidant defense pathways, such as "Ubiquitin mediated proteolysis" and "Glutathione metabolism," were identified using KEGG. In addition, quantitative real time-PCR (qRT-PCR) substantiated the up-regulation of a random selection of DEGs including antioxidant and immune defense genes. We obtained information for P. clarkii transcriptome databases and new insights into the responses of P. clarkii hepatopancreas to heavy metals.

Transcriptome analysis of differential expressed genes in hepatopancreas of Procambarus clarkii challenged with peptidoglycan.

Procambarus clarkii is one of the most economically important species in Chinese aquaculture, and is widely cultured. Infection of P. clarkii populations with bacterial pathogens causes high mortality and great economic loss, therefore disease control is of significant economic importance. P. clarkii is a model system for studying immune responses in invertebrates, and its immune system consists solely of the innate response. In the present study, we examined gene expression related to immune function in P. clarkii in response to pathogen challenge. The transcriptome of hepatopancreas tissue from P. clarkii challenged with peptidoclycan (PGN) was analyzed and compared to control specimens. After assembly and annotation, 48,661 unigenes were identified with an average length of 671.54 bp. A total of 2533 differentially expressed genes (DEGs) were obtained, including 765 significantly up-regulated unigenes and 1757 significantly down-regulated unigenes. Gene ontology (GO) analysis demonstrated 19 biological process subcategories, 16 cellular component subcategories, and 17 molecular function subcategories that were enriched among these DEGs. Enrichment analysis using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database revealed enrichment among immune responses pathways. Taken together, this study not only enriches the existing P. clarkii transcriptome database, but also elucidates immune responses of crayfish that are activated in response to PGN challenge.

Transcriptome-wide identification of differentially expressed genes in Procambarus clarkii in response to chromium challenge.

Because of the high protein content and rich meat quality of crayfish Procambarus clarkii, it has become widely popular in China in recent years and has a high economic value. When P. clarkii is stimulated by heavy metals, it reacts to oxidation. P. clarkii has evolved antioxidant defense systems, including antioxidant enzymes such as catalase (CAT). The hexavalent form of Cr (VI) is a pathogenic factor that is of particular concern in aqueous systems because of its great toxicity to living organisms. In this study, we characterized the transcriptome of P. clarkii using a RNA sequencing method and performed a comparison between K2Cr2O7-treated samples and controls. In total, 34,237 unigenes were annotated. We identified 5098 significantly differentially expressed genes (DEGs), including 2536 and 2562 were significantly up-regulated and down-regulated, respectively. In addition, quantitative real time-PCR (qRT-PCR) confirmed the up-regulation of a random selection of DEGs. Our results contribute to a more comprehensive understanding of the antioxidant defense system used by P. clarkii in response to heavy metal stress.

A myeloid differentiation factor 88 gene from yellow catfish Pelteobagrus fulvidraco and its molecular characterization in response to polyriboinosinic polyribocytidylic acid and lipopolysaccharide challenge.

Myeloid differentiation factor 88 (MyD88) is an adaptor protein of Toll-like receptor (TLR) signalling pathways that activates the innate immune system. Herein, MyD88 was identified in the economically important freshwater fish Pelteobagrus fulvidraco. The complete 2156 bp PfMyD88 cDNA includes a 147 bp 5'-untranslated region (UTR), a 1133 bp 3'-UTR, and an open reading frame (ORF) of 876 bp encoding a 291 residue protein containing Death and Toll/interleukin-1 receptor (TIR) domains. The deduced protein sequence shares 88.8%, 73.8% and 59.3% identity with orthologs in Ictalurus punctatus, Danio rerio and Homo sapiens, respectively. qRT-PCR revealed expression in all tested tissues, highest in trunk kidney, followed by spleen, and lowest in muscle. After challenge with lipopolysaccharide (LPS) or polyriboinosinic polyribocytidylic acid (Poly I:C), PfMyD88 expression was up-regulated in blood, liver, head kidney and spleen. Thus, PfMyD88 acts in innate immunity in P. fulvidraco.

The complete mitochondrial genome of Clostera anastomosis (Lepidoptera: Notodontidae) and implication for the phylogenetic relationships of Noctuoidea species.

In the present study, the complete mitochondrial genome (mitogenome) of Clostera anastomosis (C. anastomosis) has been determined for the first time. The mitogenome is 15,390 base pairs (bp) in length, comprised of 13 protein-coding genes (PCGs), 2 ribosomal RNAs (rRNAs), 22 transfer RNAs (tRNAs) and one non-coding control region (CR). The gene order shows a typical trnM rearrangement (trnM-trnI-trnQ) compared to ancestral insects (trnI-trnQ-trnM). Almost all the PCGs have the same start codon (ATN) except for cox1 (CGA), and almost all tRNAs have a typical cloverleaf secondary structure except for trnS1. At the beginning of the CR, we found a conserved motif "ATAGA + poly-T" as found in other lepidopteran insects. There are 20 intergenic regions and 11 overlapping regions, ranging from 1 to 53 bp and 1 to 9 bp, respectively. The A + T content is relatively high across the whole mitogenome. The optimal tree topologies of Noctuoidea were given by the dataset consisting of all 13 PCGs from five families (exclude Oenosandridae). Our trees suggested a topology of (Notodontidae + (Erebidae + (Nolidae + (Euteliidae + Noctuidae)))) and identified that C. anastomosis belongs to Notodontidae.