The recent emergence of numerous nanotechnologies is expected to facilitate the development of regenerative medicine, which is a tissue regeneration technique based on the replacement/repair of ...diseased tissue or organs to restore the function of lost, damaged, and aging cells in the human body. In particular, the unique magnetic properties and specific dimensions of magnetic nanomaterials make them promising innovative components capable of significantly advancing the field of tissue regeneration. Their potential applications in tissue regeneration are the focus here, beginning with the fundamentals of magnetic nanomaterials. How nanomaterials—both those that are intrinsically magnetic and those that respond to an externally applied magnetic field—can enhance the efficiency of tissue regeneration is also described. Applications including magnetically controlled cargo delivery and release, real‐time visualization and tracking of transplanted cells, magnetic regulation of cell proliferation/differentiation, and magnetic activation of targeted ion channels and signal pathways involved in regeneration are highlighted, and comments on the perspectives and challenges in magnetic nanomaterial‐based tissue regeneration are given.
The potential applications of magnetic nanomaterials in tissue regeneration are summarized. Utilization of the distinctive properties of magnetic nanomaterials in promoting tissue regeneration is highlighted, and recent advances in understanding the role of magnetic nanomaterials in regenerative medicine are discussed along with perspectives and challenges in magnetic‐nanomaterial‐based tissue regeneration.
Summary Background & aims Flavonoids may have cardioprotective effects, but epidemiological evidence on the relationship of dietary flavonoids with diabetes has not been systematically assessed. To ...examine the association between dietary flavonoids and type 2 diabetes, we performed a meta-analysis on this topic. Methods We searched PubMed through March 2013 for relevant cohort studies that assessed total flavonoids and type 2 diabetes risks. A fixed-effect model was used to calculate the summary risk estimates. Results Four articles consisting of 6 prospective cohorts that involved 18,146 cases and 284,806 participants were identified. The summary relative risk (RR) of type 2 diabetes for the highest intake of total flavonoids compared with the lowest was 0.91 (95% confidence interval (CI): 0.87–0.96). Furthermore, an increase in the total flavonoids intake of 500 mg/d was associated with a significant risk reduction of 5% (RR = 0.95, 95% CI: 0.91–0.98). In subgroup analyses, the observed beneficial effects were observed in US population, in those mean age > 40 years old people and in studies ≥20 years in duration. Conclusions The present meta-analysis indicates that consumption of dietary total flavonoids is associated with a reduced risk of type 2 diabetes.
The metallic nanostructures with unique properties of tunable plasmon resonance and large field enhancement have been cooperated with semiconductor to construct hetero‐nanostructures for various ...applications. Herein, a general and facile approach to synthesize uniform dumbbell‐like gold–sulfide core–shell hetero‐nanostructures is reported. The transformation from Au nanorods (NRs) to dumbbell‐like Au NRs and coating of metal sulfide shells (including Bi2S3, CdS, CuxS, and ZnS) are achieved in a one‐pot reaction. Due to the reshaping of Au core and the deposition of sulfide shell, the plasmon resonances of Au NRs are highly enhanced, especially the about 2 times enhancement for the visible transverse plasmon resonance compared with the initial Au NRs. Owing to the highly enhanced visible light absorption and strong local electric field, we find the photocatalytic activity of dumbbell‐like Au–Bi2S3 NRs is largely enhanced compared with pure Bi2S3 and normal Au–Bi2S3 NRs by testing the photodegradation rate of Rhodamine B (RhB). Moreover, the second‐layer sulfide can be coated and the double‐shell Au–Bi2S3–CdS hetero‐nanostructures show further improved photodegradation rate, especially about 2 times than that of Degussa P25 TiO2 (P25) ascribing to the optimum band arrangement and then the prolonged lifetime of photo‐generated carriers.
A facile method is reported to synthesize dumbbell‐like Au–metal sulfide nanorods (including CdS, Bi2S3, ZnS, and CuxS) with highly enhanced visible light absorption and strong local electric field. The double‐shell Au–Bi2S3–CdS hetero‐nanostructures show efficiently improved photodegradation rate, especially about 2 times that of Degussa P25 TiO2 (P25).
Abstract
Background
Alzheimer's disease (AD) is the most common neurodegenerative disease and its pathogenesis is still unclear. There is dysbiosis of gut microbiota in AD patients. More importantly, ...dysbiosis of the gut microbiota has been observed not only in AD patients, but also in patients with mild cognitive impairment (MCI). However, the mechanism of gut microbiota dysbiosis in AD is poorly understood. Cholinergic anti-inflammatory pathway is an important pathway for the central nervous system (CNS) regulation of peripheral immune homeostasis, especially in the gut. Therefore, we speculated that dysfunction of cholinergic anti-inflammatory pathway is a potential pathway for dysbiosis of the gut microbiota in AD.
Methods
In this study, we constructed AD model mice by injecting Aβ
1–42
into the lateral ventricle, and detected the cognitive level of mice by the Morris water maze test. In addition, 16S rDNA high-throughput analysis was used to detect the gut microbiota abundance of each group at baseline, 2 weeks and 4 weeks after surgery. Furthermore, immunofluorescence and western blot were used to detect alteration of intestinal structure of mice, cholinergic anti-inflammatory pathway, and APP process of brain and colon in each group.
Results
Aβ
1–42
i.c.v induced cognitive impairment and neuron damage in the brain of mice. At the same time, Aβ
1–42
i.c.v induced alteration of gut microbiota at 4 weeks after surgery, while there was no difference at the baseline and 2 weeks after surgery. In addition, changes in colon structure and increased levels of pro-inflammatory factors were detected in Aβ
1–42
treatment group, accompanied by inhibition of cholinergic anti-inflammatory pathways. Amyloidogenic pathways in both the brain and colon were accelerated in Aβ
1–42
treatment group.
Conclusions
The present findings suggested that Aβ in the CNS can induce gut microbiota dysbiosis, alter intestinal structure and accelerate the amyloidogenic pathways, which were related to inhibiting cholinergic anti-inflammatory pathways.
Expression levels of transmembrane protein 41A (TMEM41A) are related to the progression of malignant tumors. However, the association between TMEM41A expression and endometrial carcinoma (EC) remains ...unclear. This study aims to identify the roles of TMEM41A expression in the prognosis of patients with EC and its correlation with EC progression.
The TMEM41A expression and its correlation with the survival of patients with EC were assessed. Cox regression analysis was used to identify the prognostic factors, while nomograms were used to examine the association between the prognostic factors and the survival of patients with EC. Finally, the link between TMEM41A level and immune microenvironment and RNA modifications was investigated in EC.
TMEM41A was overexpressed in EC. TMEM41A overexpression could diagnose the EC and evaluate the poor prognosis of patients. Overexpression of TMEM41A was associated with clinical stage, age, weight, histological subtype, tumor grade, and survival status of patients with EC. Clinical stage, age, tumor grade, radiotherapy, and TMEM41A overexpression were factors of poor prognosis in patients with EC. The nomograms revealed the correlation between the TMEM41A level and survival time of patients with EC at 1, 3, and 5 years. Furthermore, TMEM41A overexpression was significantly correlated with the level of the stromal score, immune score, estimate score, NK CD56 bright cells, iDC, NK cells, eosinophils, pDC, T cells, TReg, cytotoxic cells, mast cells, Th17 cells, neutrophils, aDC, NK CD56 dim cells, TFH, Th2 cells, CD8 T cells, macrophages, immune cell markers, and RNA modifications.
TMEM41A is overexpressed in EC tissues and is associated with the prognosis, immune microenvironment, and RNA modification. Our preliminary studies indicate that overexpression of TMEM41A can potentially serve as a biomarker for EC treatment.
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•Glyoxalase 1 was increased in SH-SY5Y cells exposed to chronic high glucose.•Down-regulation of glyoxalase 1 resulted from inactivation of Nrf2/ARE pathway.•Inactivation of Nrf2/ARE ...pathway was due to alteration of Nrf2 phosphorylation.•Alteration of p-Nrf2 was involved in PKC activation and/or p38/GSK-3β inhibition.•Quercetin activated Nrf2/ARE pathway by regulating PKC and/or GSK-3β activity.
Although dietary flavonoid quercetin alleviates diabetes-associated cognitive decline in rodents, the mechanisms are not clearly clarified. This study was designed to investigate whether quercetin showed neuroprotection on central neurons against chronic high glucose through the enhancement of Nrf2/ARE/glyoxalase 1 (Glo-1) pathway. SH-SY5Y cells were divided into 8 groups: normal glucose, high glucose (HG), osmotic pressure control, solvent control, HG plus low, middle, high concentrations of quercetin, or Nrf2 activator (sulforaphane). After treatment for 72 h, the associated parameters were measured. We found quercetin and sulforaphane increased cell viability, and enhanced Glo-1 functions (Glo-1 activity, the reduced glutathione and advanced glycation end-products levels) as well as Glo-1 protein and mRNA levels in SH-SY5Y cells cultured with HG. Meanwhile, quercetin and sulforaphane activated Nrf2/ARE pathway, reflected by the raised Nrf2 and p-Nrf2 levels, and the elevated protein and mRNA levels of γ-glutamycysteine synthase (γ-GCS), a known target gene of Nrf2/ARE signaling. Moreover, Nrf2/ARE pathway was activated after pretreatment with a PKC activator, p38 MAPK inhibitor, or GSK-3β inhibitor under the condition of HG, and quercetin addition further strengthened this pathway; however, PKC inhibition or GSK-3β activation pretreatment reversed the effects of quercetin on the protein expression of γ-GCS in the HG condition. In summary, quercetin exerts the neuroprotection by enhancing Glo-1 functions in central neurons under chronic HG condition, which may be mediated by activation of Nrf2/ARE pathway; furthermore, the increased Nrf2 phosphorylation mediated by PKC activation and/or GSK-3β inhibition may involve in the activation of Nrf2/ARE pathway.
Heteroblasty refers to a phenomenon that a plant produces morphologically or functionally different lateral organs in an age‐dependent manner. In the model plant Arabidopsis thaliana, the production ...of trichomes (epidermal leaf hairs) on the abaxial (lower) side of leaves is a heteroblastic mark for the juvenile‐to‐adult transition. Here, we show that the heteroblastic development of abaxial trichomes is regulated by a spatiotemporally regulated complex comprising the leaf abaxial fate determinant (KAN1) and the developmental timer (miR172‐targeted AP2‐like proteins). We provide evidence that a short‐distance chromatin loop brings the downstream enhancer element into close association with the promoter elements of GL1, which encodes a MYB transcription factor essential for trichome initiation. During juvenile phase, the KAN1‐AP2 repressive complex binds to the downstream sequence of GL1 and represses its expression through chromatin looping. As plants age, the gradual reduction in AP2‐like protein levels leads to decreased amount of the KAN1‐AP2 complex, thereby licensing GL1 expression and the abaxial trichome initiation. Our results thus reveal a novel molecular mechanism by which a heteroblastic trait is governed by integrating age and leaf polarity cue in plants.
Synopsis
Age‐dependent development of leaf hairs (trichomes) on the abaxial (lower) leaf surface in Arabidopsis is regulated by integration of positional and temporal cues via a transcriptional complex comprising the leaf abaxial fate determinant KAN1 and the AP2‐like transcription factor TOE1 acting as a developmental timer.
AP2‐like proteins, including TOE1, repress abaxial trichome formation in juvenile leaves.
TOE1 forms a repressive complex with KAN1.
KAN1‐ complex binds to the 3′ downstream sequence of GL1, a master regulator of leaf trichome production.
KAN1/TOE1 represses GL1 expression through chromatin‐loop mediated histone deacetylation.
Regulated association of leaf polarity regulator KAN1 and AP2‐like transcription factor TOE1 represses leaf trichome formation in juvenile leaves via chromatin‐based mechanisms.
Most vertebrates reproduce sexually, and plastic sex determination mechanisms including genotypic sex determination (GSD) and environmental sex determination (ESD) have been extensively revealed. ...However, why sex determination mechanisms evolve diversely and how they correlate with diverse reproduction strategies remain largely unclear. Here, we utilize the superiority of a hexaploid gibel carp (Carassius gibelio) that is able to reproduce by unisexual gynogenesis and contains a rare but diverse proportion of males to investigate these puzzles. A total of 2248 hexaploid specimens were collected from 34 geographic wild populations throughout mainland China, in which 24 populations were revealed to contain 186 males with various incidences ranging from 1.2 to 26.5%. Subsequently, the proportion of temperature-dependent sex determination (TSD) was revealed to be positively correlated to average annual temperature in wild populations, and male incidence in lab gynogenetic progenies was demonstrated to increase with the increasing of larval rearing temperature. Meanwhile, extra microchromosomes were confirmed to play genotypic male determination role as previously reported. Thereby, GSD and TSD were found to coexist in gibel carp, and the proportions of GSD were observed to be much higher than that of TSD in sympatric wild populations. Our findings uncover a potential new mechanism in the evolution of sex determination system in polyploid vertebrates with unisexual gynogenesis ability, and also reveal a possible association of sex determination mechanism transition between TSD and GSD and reproduction mode transition between unisexual gynogenesis and bisexual reproduction.
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