Two intrinsic timing mechanisms set start and end times for dendritic arborization of a nociceptive neuron.

Choreographic dendritic arborization takes place within a defined time frame, but the timing mechanism is currently not known. Here, we report that the precisely timed lin-4-lin-14 regulatory circuit triggers an initial dendritic growth activity, whereas the precisely timed lin-28-let-7-lin-41 regulatory circuit signals a subsequent developmental decline in dendritic growth ability, hence restricting dendritic arborization within a set time frame. Loss-of-function mutations in the lin-4 microRNA gene cause limited dendritic outgrowth, whereas loss-of-function mutations in its direct target, the lin-14 transcription factor gene, cause precocious and excessive outgrowth. In contrast, loss-of-function mutations in the let-7 microRNA gene prevent a developmental decline in dendritic growth ability, whereas loss-of-function mutations in its direct target, the lin-41 tripartite motif protein gene, cause further decline. lin-4 and let-7 regulatory circuits are expressed in the right place at the right time to set start and end times for dendritic arborization. Replacing the lin-4 upstream cis-regulatory sequence at the lin-4 locus with a late-onset let-7 upstream cis-regulatory sequence delays dendrite arborization, whereas replacing the let-7 upstream cis-regulatory sequence at the let-7 locus with an early-onset lin-4 upstream cis-regulatory sequence causes a precocious decline in dendritic growth ability. Our results indicate that the lin-4-lin-14 and the lin-28-let-7-lin-41 regulatory circuits control the timing of dendrite arborization through antagonistic regulation of the DMA-1 receptor level on dendrites. The LIN-14 transcription factor likely directly represses dma-1 gene expression through a transcriptional means, whereas the LIN-41 tripartite motif protein likely indirectly promotes dma-1 gene expression through a posttranscriptional means.

A gain-of-function mutation in Msl10 triggers cell death and wound-induced hyperaccumulation of jasmonic acid in Arabidopsis.

Jasmonates (JAs) are rapidly induced after wounding and act as key regulators for wound induced signaling pathway. However, what perceives the wound signal and how that triggers JA biosynthesis remains poorly understood. To identify components involved in Arabidopsis wound and JA signaling pathway, we screened for mutants with abnormal expression of a luciferase reporter, which is under the control of a wound-responsive promoter of an ethylene response factor (ERF) transcription factor gene, RAP2.6 (Related to APetala 2.6). The rea1 (RAP2.6 expresser in shoot apex) mutant constitutively expressed the RAP2.6-LUC reporter gene in young leaves. Along with the typical JA phenotypes including shorter petioles, loss of apical dominance, accumulation of anthocyanin pigments and constitutive expression of JA response gene, rea1 plants also displayed cell death and accumulated high levels of JA in response to wounding. The phenotype of rea1 mutant is caused by a gain-of-function mutation in the C-terminus of a mechanosensitive ion channel MscS-like 10 (MSL10). MSL10 is localized in the plasma membrane and is expressed predominantly in root tip, shoot apex and vascular tissues. These results suggest that MSL10 is involved in the wound-triggered early signal transduction pathway and possibly in regulating the positive feedback synthesis of JA.

Transcriptome signatures of the medial prefrontal cortex underlying GABAergic control of resilience to chronic stress exposure.

Analyses of postmortem human brains and preclinical studies of rodents have identified somatostatin (SST)-positive interneurons as key elements that regulate the vulnerability to stress-related psychiatric disorders. Conversely, genetically induced disinhibition of SST neurons or brain region-specific chemogenetic activation of SST neurons in mice results in stress resilience. Here, we used RNA sequencing of mice with disinhibited SST neurons to characterize the transcriptome changes underlying GABAergic control of stress resilience. We found that stress resilience of male but not female mice with disinhibited SST neurons is characterized by resilience to chronic stress-induced transcriptome changes in the medial prefrontal cortex. Interestingly, the transcriptome of non-stressed stress-resilient male mice resembled the transcriptome of chronic stress-exposed stress-vulnerable mice. However, the behavior and the serum corticosterone levels of non-stressed stress-resilient mice showed no signs of physiological stress. Most strikingly, chronic stress exposure of stress-resilient mice was associated with an almost complete reversal of their chronic stress-like transcriptome signature, along with pathway changes indicating stress-induced enhancement of mRNA translation. Behaviorally, the mice with disinhibited SST neurons were not only resilient to chronic stress-induced anhedonia - they also showed an inversed anxiolytic-like response to chronic stress exposure that mirrored the chronic stress-induced reversal of the chronic stress-like transcriptome signature. We conclude that GABAergic dendritic inhibition by SST neurons exerts bidirectional control over behavioral vulnerability and resilience to chronic stress exposure that is mirrored in bidirectional changes in expression of putative stress resilience genes, through a sex-specific brain substrate.

Self-heating mitochondrion-induced free radical blast for immunogenic cell death stimulation and HCC immunotherapy.

Hepatocellular carcinoma (HCC) is an immunosuppressive tumor associated with high mortality. Photothermal and photodynamic therapies have been applied to induce immunogenic cell death (ICD) in HCC, successfully eliciting immune responses but facing limitations in penetration depth in clinical trials. Here, intrinsic mitochondrial hyperthermia was used to trigger thermosensitive drug release. The mitochondria were further self-heated through 2,4-dinitrophenol uncoupling, dramatically promoting free radical initiation and inducing tumor ICD. The synthesized mitochondrial-targeting TPP-HA-TDV nanoparticles specifically generated free radicals in the mitochondria without external stimulation, and obviously enhanced the release of ICD markers, subsequently evoking immune responses. The results showed that mitochondrial hyperthermia could be an endogenous target for thermosensitive drug release. Furthermore, self-heating mitochondria-induced free radical blast could be an efficient therapeutic for deep-seated tumor therapy.

SIRT3: A potential therapeutic target for liver fibrosis.

Sirtuin3 (SIRT3) is a nicotinamide adenine dinucleotide (NAD+)-dependent protein deacetylase located in the mitochondria, which mainly regulates the acetylation of mitochondrial proteins. In addition, SIRT3 is involved in critical biological processes, including oxidative stress, inflammation, DNA damage, and apoptosis, all of which are closely related to the progression of liver disease. Liver fibrosis characterized by the deposition of extracellular matrix is a result of long termed or repeated liver damage, frequently accompanied by damaged hepatocytes, the recruitment of inflammatory cells, and the activation of hepatic stellate cells. Based on the functions and pharmacology of SIRT3, we will review its roles in liver fibrosis from three aspects: First, the main functions and pharmacological effects of SIRT3 were investigated based on its structure. Second, the roles of SIRT3 in major cells in the liver were summarized to reveal its mechanism in developing liver fibrosis. Last, drugs that regulate SIRT3 to prevent and treat liver fibrosis were discussed. In conclusion, exploring the pharmacological effects of SIRT3, especially in the liver, may be a potential strategy for treating liver fibrosis.

Comparative analysis of the influence of various materials on the state of the roadside environment during the road repair.

The relevance of the study is conditioned by the urgent need for the practical derivation of clear criteria for assessing the degree of influence of certain materials used in road construction on the state of the roadside environment directly during such works, including the overall environmental situation in the area. In this context, the main purpose of this study is to conduct an experimental investigation to determine the physical and mechanical properties and durability of some building materials used during road repair, to perform a comparative analysis of the results obtained to determine their optimal use in terms of influencing the state of the roadside environment during the repair of a highway section. The leading method in this study is a combination of a systematic analysis of the influence of various materials on the state of the roadside environment during the repair with experimental studies. The results obtained indicate the different influence of materials used in road repair works on the state of the roadside environment and the need to choose their optimal combination in the future when repairing the roadway. The results obtained and the practical conclusions formed on their basis will be of significant importance directly for the employees of the road repair services, who, by their occupation, solve the issues of using specific building materials when repairing and eliminating damage to the roadway, as well as for researchers who solve theoretical problems of choosing specific materials for carrying out repair works, from the standpoint of assessing their impact on the roadside environment.

From liver fibrosis to hepatocarcinogenesis: Role of excessive liver H2O2 and targeting nanotherapeutics.

Liver fibrosis and hepatocellular carcinoma (HCC) have been worldwide threats nowadays. Liver fibrosis is reversible in early stages but will develop precancerosis of HCC in cirrhotic stage. In pathological liver, excessive H2O2 is generated and accumulated, which impacts the functionality of hepatocytes, Kupffer cells (KCs) and hepatic stellate cells (HSCs), leading to genesis of fibrosis and HCC. H2O2 accumulation is associated with overproduction of superoxide anion (O2 •-) and abolished antioxidant enzyme systems. Plenty of therapeutics focused on H2O2 have shown satisfactory effects against liver fibrosis or HCC in different ways. This review summarized the reasons of liver H2O2 accumulation, and the role of H2O2 in genesis of liver fibrosis and HCC. Additionally, nanotherapeutics targeting H2O2 were summarized for further consideration of antifibrotic or antitumor therapy.

Nanodrug rescues liver fibrosis via synergistic therapy with H2O2 depletion and Saikosaponin b1 sustained release.

Hypoxia and hydrogen peroxide (H2O2) accumulation form the profibrogenic liver environment, which involves fibrogenesis and chronic stimulation of hepatic stellate cells (HSCs). Catalase (CAT) is the major antioxidant enzyme that catalyzes H2O2 into oxygen and water, which loses its activity in different liver diseases, especially in liver fibrosis. Clinical specimens of cirrhosis patients and liver fibrotic mice are collected in this work, and results show that CAT decrease is closely correlated with hypoxia-induced transforminmg growth factor ß1 (TGF-ß1). A multifunctional nanosystem combining CAT-like MnO2 and anti-fibrosis Saikosaponin b1 (Ssb1) is subsequently constructed for antifibrotic therapy. MnO2 catalyzes the accumulated H2O2 into oxygen, thereby ameliorating the hypoxic and oxidative stress to prevent activation of HSCs, and assists to enhance the antifibrotic pharmaceutical effect of Ssb1. This work suggests that TGF-ß1 is responsible for the diminished CAT in liver fibrosis, and our designed MnO2@PLGA/Ssb1 nanosystem displays enhanced antifibrotic efficiency through removing excess H2O2 and hypoxic stress, which may be a promising therapeutic approach for liver fibrosis treatment.

Reduction-responsive nucleic acid nanocarrier-mediated miR-22 inhibition of PI3K/AKT pathway for the treatment of patient-derived tumor xenograft osteosarcoma.

miRNAs are important regulators of gene expression and play key roles in the development of cancer, including osteosarcoma. During the development of osteosarcoma, the expression of miR-22 is significantly downregulated, making miR-22 as a promising therapeutic target against osteosarcoma. To design and fabricate efficient delivery carriers of miR-22 into osteosarcoma cells, a hydroxyl-rich reduction-responsive cationic polymeric nanoparticle, TGIC-CA (TC), was developed in this work, which also enhanced the therapeutic effects of Volasertib on osteosarcoma. TC was prepared by the ring-opening reaction between amino and epoxy groups by one-pot method, which had the good complexing ability with nucleic acids, reduction-responsive degradability and gene transfection performance. TC/miR-22 combined with volasertib could inhibit proliferation, migration and promote apoptosis of osteosarcoma cells in vitro. The anti-tumor mechanisms were revealed as TC/miR-22 and volasertib could inhibit the PI3K/Akt signaling pathway synergistically. Furthermore, this strategy showed outstanding tumor suppression performance in animal models of orthotopic osteosarcoma, especially in patient-derived chemo-resistant and chemo-intolerant patient-derived xenograft (PDX) models, which reduced the risk of tumor lung metastasis and overcame drug resistance. Therefore, it has great potential for efficient treatment of metastasis and drug resistance of osteosarcoma by the strategy of localized, sustained delivery of miR-22 using the cationic nanocarriers combined with non-traditional chemotherapy drugs.

Polyaminoglycoside-mediated cell reprogramming system for the treatment of diabetes mellitus.

Diabetes mellitus is a disease of metabolism, featuring persistent hyperglycaemia due to insufficient insulin secretion or insulin resistance. At present, the generation of new beta cells from autologous cells by ectopic expression of specific transcription factors is a promising treatment for diabetes. The application of this strategy urgently needs safe and effective gene delivery vectors. In this work, a therapeutic plasmid (pNPMN-PBase), combined multiple specific transcription factors Ngn3, Pdx1, Mafa and Neruod1 (NPMN), was firstly constructed. Then, phenylboronic acid (PBA)-functionalized branched polymers (SS-HPT-P) have been proposed to deliver pNPMN-PBasefor the promising treatment of diabetes. SS-HPT-P had good biocompatibility and low cytotoxicity, and could achieve liver-targeted delivery. SS-HPT-P/pNPMN-PBase system can effectively realize the liver delivery of exogenous therapeutic genes, induce the reprogramming of hepatocytes into beta-like cells, reestablish the endogenous insulin-expression system, and alleviate diabetes and its complications. The present study thus provides an effective strategy for the cell replacement therapy of diabetes.

Phenylboronic acid-functionalized polyaminoglycoside as an effective CRISPR/Cas9 delivery system.

Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) gene editing technology is a promising approach for cancer therapy, and its application practice urgently requires a safe and effective gene carrier. In this work, we focus on the design of a phenylboronic acid (PBA)-functionalized, disulfide bonded branched polyaminoglycoside (SS-HPT-P) as a robust delivery vector of the CRISPR-Cas9 system. SS-HPT-P showed great tumor-targeting performance, reduction-responsive degradability, and gene transfection ability. The typical pCas9-surv (one CRISPR-Cas9 plasmid that targets and knocks out the survivin gene) delivery mediated by SS-HPT-P exhibited gene editing performance in the A549 cell line, confirming the feasibility of SS-HPT-P to effectively deliver the CRISPR-Cas9 system. SS-HPT-P/pCas9-surv could effectively inhibit the proliferation of tumor cells both in vitro and in vivo, suggesting the potential of PBA-functionalized nanocarriers for cancer gene therapy. The present work provides a promising approach for the treatment of malignant tumors.

Combined Cornus Officinalis and Paeonia Lactiflora Pall Therapy Alleviates Rheumatoid Arthritis by Regulating Synovial Apoptosis via AMPK-Mediated Mitochondrial Fission.

Rheumatoid arthritis (RA) is a chronic autoimmune disease that leads to cartilage destruction and bone erosion. In-depth exploration of the pathogenesis of RA and the development of effective therapeutic drugs are of important clinical and social value. Herein, we explored the medicinal value of Cornus officinalis Sieb. and Paeonia lactiflora Pall. in RA treatment using a rat model of collagen-induced arthritis (CIA). We compared the therapeutic effect of Cornus officinalis and Paeonia lactiflora with that of their main active compounds, ursolic acid and paeoniflorin, respectively. We demonstrated that the combination of Cornus officinalis and Paeonia lactiflora effectively inhibited the release of factors associated with oxidative stress and inflammation during RA, therein ameliorating the symptoms and suppressing the progression of RA. We further showed that the underlying mechanisms may be related to the regulation of apoptosis in synovial tissues, and we investigated the potential involvement of AMPK-mediated mitochondrial dynamics in the therapeutic action of the two drugs and their active components.

Reversible Treatment of Pressure Overload-Induced Left Ventricular Hypertrophy through Drd5 Nucleic Acid Delivery Mediated by Functional Polyaminoglycoside.

Left ventricular hypertrophy and fibrosis are major risk factors for heart failure, which require timely and effective treatment. Genetic therapy has been shown to ameliorate hypertrophic cardiac damage. In this study, it is found that in mice, the dopamine D5 receptor (D5R) expression in the left ventricle (LV) progressively decreases with worsening of transverse aortic constriction-induced left ventricular hypertrophy. Then, a reversible treatment of left ventricular hypertrophy with Drd5 nucleic acids delivered by tobramycin-based hyperbranched polyaminoglycoside (SS-HPT) is studied. The heart-specific increase in D5R expression by SS-HPT/Drd5 plasmid in the early stage of left ventricular hypertrophy attenuates cardiac hypertrophy and fibrosis by preventing oxidative and endoplasmic reticulum (ER) stress and ameliorating autophagic dysregulation. By contrast, SS-HPT/Drd5 siRNA promotes the progression of left ventricular hypertrophy and accelerates the deterioration of myocardial function into heart failure. The reduction in cardiac D5R expression and dysregulated autophagy are observed in patients with hypertrophic cardiomyopathy and heart failure. The data show a cardiac-specific beneficial effect of SS-HPT/Drd5 plasmid on myocardial remodeling and dysfunction, which may provide an effective therapy of patients with left ventricular hypertrophy and heart failure.

Multifunctional Delivery Nanosystems Formed by Degradable Antibacterial Poly(Aspartic Acid) Derivatives for Infected Skin Defect Therapy.

Nucleic acid (NA)-based therapy is promising for tissue repair, such as skin and bone defect therapy. However, bacterial infections often occur in the process of tissue healing. The ideal treatment of tissue repair requires both anti-infection and simultaneous tissue healing. The epidermal growth factor (EGF) plays an important role in wound healing processes. In this work, degradable antibacterial gene vectors based on tobramycin (clinically relevant antibiotic) conjugated poly(aspartic acid) (TPT) are proposed as multifunctional delivery nanosystems of plasmid encoding EGF (pEGF) to realize the antibacterial therapy and tissue healing of infected skin defects. TPT has low cytotoxicity and good degradability, which is helpful in the NA delivery process. TPT demonstrates good transfection performances and hemocompatibility, as well as excellent antibacterial activities in vitro. The outstanding pEGF delivery ability of TPT and the bioactivity of expressed EGF facilitate the proliferation of fibroblast cells. The effective in vivo infected skin defect therapy is also demonstrated with TPT/pEGF nanocomplexes, where skin tissue healing is promoted. The present work opens new avenues for the design of multifunctional delivery nanosystems with antibacterial ability to treat infected tissue defect.