Polyhydroxybutyrate production from crude glycerol using a highly robust bacterial strain Halomonas sp. YLGW01

Petrochemical-based plastics are hardly biodegradable and a major cause of environmental pollution, and polyhydroxybutyrate (PHB) is attracting attention as an alternative due to its similar properties. However, the cost of PHB production is high and is considered the greatest challenge for its industrialization. Here, crude glycerol was used as a carbon source for more efficient PHB production. Among the 18 strains investigated, Halomonas taeanenisis YLGW01 was selected for PHB production due to its salt tolerance and high glycerol consumption rate. Furthermore, this strain can produce poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P(3HB-co-3 HV)) with 17 % 3 HV mol fraction when a precursor is added. PHB production was maximized through medium optimization and activated carbon treatment of crude glycerol, resulting in 10.5 g/L of PHB with 60 % PHB content in fed-batch fermentation. Physical properties of the produced PHB were analyzed, i.e., weight average molecular weight (6.8 × 10⁵), number average molecular weight (4.4 × 10⁵), and the polydispersity index (1.53). In the universal testing machine analysis, the extracted intracellular PHB showed a decrease in Young's modulus, an increase in Elongation at break, greater flexibility than authentic film, and decreased brittleness. This study confirmed that YLGW01 is a promising strain for industrial PHB production using crude glycerol.

Enhanced production of bio-indigo in engineered Escherichia coli, reinforced by cyclopropane-fatty acid-acyl-phospholipid synthase from psychrophilic Pseudomonas sp. B14-6

Indigo dye is an organic compound with a distinctive blue color. Most of the indigo currently used in industry is produced via chemical synthesis, which generates a large amount of wastewater. Therefore, several studies have recently been conducted to find ways to produce indigo eco-friendly using microorganisms. Here, we produced indigo using recombinant Escherichia coli with both an indigo-producing plasmid and a cyclopropane fatty acid (CFA)-regulating plasmid. The CFA-regulating plasmid contains the cfa gene, and its expression increases the CFA composition of the phospholipid fatty acids of the cell membrane. Overexpression of cfa showed cytotoxicity resistance of indole, an intermediate product formed during the indigo production process. This had a positive effect on indigo production and cfa originated from Pseudomonas sp. B 14-6 was used. Optimal conditions for indigo production were determined by adjusting the expression strain, culture temperature, shaking speed, and isopropyl β-D-1-thiogalactopyranoside concentration. Treatment with Tween 80 at a particular concentration to increase the permeability of the cell membrane had a positive effect on indigo production. The strain with the CFA plasmid produced 4.1 mM of indigo after 24 h of culture and produced 1.5-fold higher indigo than the control strain without the CFA plasmid that produced 2.7 mM.

GRAS-1 is a novel regulator of early meiotic chromosome dynamics in C. elegans

Chromosome movements and licensing of synapsis must be tightly regulated during early meiosis to ensure accurate chromosome segregation and avoid aneuploidy, although how these steps are coordinated is not fully understood. Here we show that GRAS-1, the worm homolog of mammalian GRASP/Tamalin and CYTIP, coordinates early meiotic events with cytoskeletal forces outside the nucleus. GRAS-1 localizes close to the nuclear envelope (NE) in early prophase I and interacts with NE and cytoskeleton proteins. Delayed homologous chromosome pairing, synaptonemal complex (SC) assembly, and DNA double-strand break repair progression are partially rescued by the expression of human CYTIP in gras-1 mutants, supporting functional conservation. However, Tamalin, Cytip double knockout mice do not exhibit obvious fertility or meiotic defects, suggesting evolutionary differences between mammals. gras-1 mutants show accelerated chromosome movement during early prophase I, implicating GRAS-1 in regulating chromosome dynamics. GRAS-1-mediated regulation of chromosome movement is DHC-1-dependent, placing it acting within the LINC-controlled pathway, and depends on GRAS-1 phosphorylation at a C-terminal S/T cluster. We propose that GRAS-1 coordinates the early steps of homology search and licensing of SC assembly by regulating the pace of chromosome movement in early prophase I.

Case report: Metastatic urothelial cancer with an exceptional response to immunotherapy and comprehensive understanding of the tumor and the tumor microenvironment

Although immune checkpoint inhibitors (ICIs) are increasingly used as second-line treatments for urothelial cancer (UC), only a small proportion of patients respond. Therefore, understanding the mechanisms of response to ICIs is critical to improve clinical outcomes for UC patients. The tumor microenvironment (TME) is recognized as a key player in tumor progression and the response to certain anti-cancer treatments. This study aims to investigate the mechanism of response using integrated genomic and transcriptomic profiling of a UC patient who was part of the KEYNOTE-045 trial and showed an exceptional response to pembrolizumab. Diagnosed in 2014 and receiving first-line chemotherapy without success, the patient took part in the KEYNOTE-045 trial for 2 years. She showed dramatic improvement and has now been free of disease for over 6 years. Recently described by Bagaev et al., the Molecular Functional (MF) Portrait was utilized to dissect genomic and transcriptomic features of the patient's tumor and TME. The patient's tumor was characterized as Immune Desert, which is suggestive of a non-inflamed microenvironment. Integrated whole-exome sequencing (WES) and RNA sequencing (RNA-seq) analysis identified an ATM mutation and high TMB level (33.9 mut/mb), which are both positive biomarkers for ICI response. Analysis further revealed the presence of the APOBEC complex, indicating the potential for use of APOBEC signatures as predictive biomarkers for immunotherapy response. Overall, comprehensive characterization of the patient's tumor and TME with the MF Portrait revealed important insights that could potentially be hypothesis generating to identify clinically useful biomarkers and improve treatment for UC patients.

Targeting spinal microglia with fexofenadine-loaded nanoparticles prolongs pain relief in a rat model of neuropathic pain

Targeting microglial activation is emerging as a clinically promising drug target for neuropathic pain treatment. Fexofenadine, a histamine receptor 1 antagonist, is a clinical drug for the management of allergic reactions as well as pain and inflammation. However, the effect of fexofenadine on microglial activation and pain behaviors remains elucidated. Here, we investigated nanomedicinal approach that targets more preferentially microglia and long-term analgesics. Fexofenadine significantly abolished histamine-induced microglial activation. The fexofenadine-encapsulated poly(lactic-co-glycolic acid) nanoparticles (Fexo NPs) injection reduced the pain sensitivity of spinal nerve ligation rats in a dose-dependent manner. This alleviation was sustained for 4 days, whereas the effective period by direct fexofenadine injection was 3 h. Moreover, Fexo NPs inhibited microglial activation, inflammatory signaling, cytokine release, and a macrophage phenotype shift towards the alternative activated state in the spinal cord. These results show that Fexo NPs exhibit drug repositioning promise as a long-term treatment modality for neuropathic pain.

Longitudinal molecular analysis of tumor exome and transcriptome to evaluate clonal evolution and identify novel therapeutic targets in thymoma

e20624

Background: The rarity of thymic epithelial tumors has limited mechanistic understanding of tumor biology and the rational identification of potential therapeutic targets for patients with advanced disease. While the Cancer Genome Atlas Project enabled multi-omic profiling of thymic epithelial tumors, the majority of samples were early-stage and chemotherapy-naïve. Furthermore, next generation sequencing for patients with advanced disease often provides only a limited breadth of genome coverage. The genetic changes in thymic epithelial tumors that evolve through disease progression and treatment represent a current knowledge gap and opportunity for reassessment of new therapeutic targets. Methods: To address these points, we conducted whole exome and bulk RNA transcriptome sequencing for serially-collected FFPE archival tumor samples from a patient with Stage IVA, WHO B2/B3 thymoma using the BostonGene Tumor Portrait Test version 1.3. Samples analyzed include the initial primary tumor resected without induction treatment; two subsequent, metachronous pleural recurrences resected without any induction treatment; and a third pleural metastasis resected following two cycles of induction chemotherapy with Cisplatin/Adriamycin/Cyclophosphamide without interval radiographic evidence of treatment response. Results: Tumor characteristics were largely consistent with prior molecular studies, and without significant evidence of major clonal evolutionary changes based on single nucleotide polymorphisms, insertions/deletions or copy number alterations. Tumor mutational burden was recurrently low (< 1 mutation per megabase) with stable microsatellite status. EGFR copy number gain was observed (+1 copy) across recurrent pleural resection specimens. While the degree of copy number gain did not change with disease progression, increasing EGFR transcript counts were observed and evaluated by IHC. Other notable therapeutic biomarkers included absent TGFB1 and present VEGFA expression. Collective RNA-based gene expression changes were compared with the Thymic TCGA cohort for reference. Conclusions: Our analysis illustrates the narrow clonal evolution of a thymic epithelial tumor through treatment—both with and without the selective pressures of induction chemotherapy. This suggests that the genomic features of advanced thymoma may reflect the treatment-naïve state as described in the TCGA, one marked by a low mutational burden but with recurrent copy number alterations in select genes. Complementary transcriptome sequencing identified EGFR expression as a promising therapeutic target for further study. Taken together, these findings illustrate the hypothesis-generating potential for deep molecular analysis with whole exome and transcriptome sequencing to improve the understanding of rare tumors.

Reconstructing the tumor microenvironment to unlock therapeutic options in pancreatic cancer

589

Background: Spatiotemporal heterogeneity, paucity of actionable targets, and complexity of the tumor microenvironment (TME) are major barriers to therapeutic advances in pancreatic ductal adenocarcinoma (PDAC). We reconstructed the transcriptomic data from a heterogeneous cohort of PDAC patients (pts) to examine the TME and identify putative therapeutic strategies. Methods: Transcriptomic profiling and targeted gene sequencing data (Tempus) on primary or metastatic specimens from PDAC pts treated at the Medical College of Wisconsin (MCW) between 2015-2020 were analyzed. Mutation calling, expression analysis, cell type deconvolution from the transcriptome, and TME reconstruction were performed using BostonGene’s automated pipelines. Mann-Whitney U test and Fisher's exact test were used to assess statistical significance. Results: The cohort (N = 79) comprised of resectable (19%), borderline resectable (37%), locally advanced (24%) and metastatic (20%) PDAC pts. The most frequently used tumor sites for transcriptomic profiling were pancreas primary (59%), liver (16%), lung (10%) and peritoneum (10%). Four distinct subtypes were identified based on the BostonGene classification of the transcriptomic TME– Immune Enriched (IE; 14%), Fibrotic (F; 28%), Immune Enriched & Fibrotic (IEF; 36%), and Immune Depleted (ID; 22%). Analyses of the cellular composition of the TME subtypes with RNA-seq-based deconvolution showed that T-cell fractions (CD4, CD8) were higher in the IE/IEF subtypes compared to the F/ID subtypes (CD8 means: 6.4% vs 2.9%, p < 0.001; CD4 means: 15.1% vs. 7.6%, p < 0.001), while fibroblast content was higher in the F/IEF subtypes compared to the IE/ID subtypes (37.4% vs 18.4%; p < 0.001). KRAS wild-type (WT) tumors were enriched in the IEF subtype (58%), while KRAS mutated tumors comprised all four transcriptomic subtypes. Primary PDACs that underwent radiotherapy were significantly more enriched in fibroblasts compared to samples from the TCGA cohort that did not undergo radiotherapy (means: 30%(MCW) vs. 20% (TCGA), p < 0.001). Primary PDACs were enriched in the IEF subtype (46%), while liver and lung metastases were enriched in the ID (74%) and IE subtypes (70%), respectively. When pts were dichotomized to short (< 400 days) versus long (> 800 days) survivors, tumors from pts with longer survival demonstrated a trend towards enrichment in CD4/CD8 T cells and IE subtype that did not meet statistical significance. Conclusions: Lung metastases and KRAS WT PDACs harbor an immunogenic TME while liver metastases harbor an immune-cold TME, highlighting the biologic heterogeneity of PDAC. The efficacy of immunotherapeutic strategies in PDAC pts who demonstrate an IE/IEF transcriptomic subtype merits prospective evaluation. The four distinct subtypes identified by TME transcriptomic classification highlight the possibility of personalized immunotherapeutic strategies in PDAC.

Association between Unhealthful Plant-Based Diets and Possible Risk of Dyslipidemia

The relationship between the various types of diets derived from plants and vulnerability of dyslipidemia has rarely been investigated, and limited data exist in Asians whose dietary pattern is fairly different from that of the Western population. We aim to analyze the relationship between three plant-based diet indices (PDI) and the risk of dyslipidemia. Participants included 173,209 Korean adults who were aged ≥40 years from the Korean Genome and Epidemiology Study_Health Examination (2004–2013). A food frequency questionnaire (FFQ) was used to assess dietary intake. Three PDI were quantified for the study: overall PDI, healthful PDI (hPDI), and unhealthful PDI (uPDI). Among the 147,945 included, 48,166 (32.6%) of participants had dyslipidemia. Great adherence to uPDI was related with 15% greater odds of having dyslipidemia (OR: 1.15; 95% CI: 1.11–1.20, p-trend < 0.0001). No significant association was observed between PDI, hPDI, and dyslipidemia. The association between uPDI and dyslipidemia was significantly stronger among participants aged ≥55 years when compared to participants aged <55 years (p-value for interaction = 0.001). The quality of plant foods is vital in preventing dyslipidemia among people consuming high plant-based food diets.

Social isolation-related depression accelerates ethanol intake via microglia-derived neuroinflammation

Social isolation is common in modern society and is a contributor to depressive disorders. People with depression are highly vulnerable to alcohol use, and abusive alcohol consumption is a well-known obstacle to treating depressive disorders. Using a mouse model involving isolation stress (IS) and/or ethanol intake, we investigated the mutual influence between IS-derived depressive and ethanol-seeking behaviors along with the underlying mechanisms. IS increased ethanol craving, which robustly exacerbated depressive-like behaviors. Ethanol intake activated the mesolimbic dopaminergic system, as evidenced by dopamine/tyrosine hydroxylase double-positive signals in the ventral tegmental area and c-Fos activity in the nucleus accumbens. IS-induced ethanol intake also reduced serotonergic activity, via microglial hyperactivation in raphe nuclei, that was notably attenuated by a microglial inhibitor (minocycline). Our study demonstrated that microglial activation is a key mediator in the vicious cycle between depression and alcohol consumption. We also propose that dopaminergic reward might be involved in this pathogenicity.

Heart Rate Variability as an Early Objective Indicator of Subjective Feeling of Depression in Daily Life

Objectives

Changes in the autonomic nervous system have been observed in patients with depressive disorders by measuring their heart rate variability (HRV). However, whether HRV associates with depressive events in healthy people remains unknown.

Methods

Four healthy people participated in the present study. Their HRVs were measured routinely for 6 to 13 months. During this time, two participants reported experiencing two and three bouts of depression, respectively. This approach allowed us to examine changes in the participants’ HRVs by comparing their HRVs from before and after the unexpected depressive events. Changes in HRV were compared against those of two participants who did not report any depressive event.

Results

Participants’ low frequency/high frequency (LF/HF) ratios of HRV were lower after the event of depression than before. Their LF/HF ratios increased after recovery from the depressive events. In contrast, two participants who did not report any depressive event showed relatively smaller changes in their LF/HF ratios across measurements.

Conclusions

These results suggest that the LF/HF ratio may provide an objective measure of subjective experiences of depression and help identify potential cases of clinical depression.

Application of PLGA nanoparticles to enhance the action of duloxetine on microglia in neuropathic pain

Duloxetine (DLX) is a selective serotonin and noradrenaline reuptake inhibitor (SNRI) used for the treatment of pain, but it has been reported to show side effects in 10-20% of patients. Its analgesic efficacy in central pain is putatively related to its influence on descending inhibitory neuronal pathways. However, DLX can also affect the activation of microglia. This study was performed to investigate whether PLGA nanoparticles (NPs), which are expected to enhance targeting to microglia, can improve the analgesic efficacy and limit the side effects of DLX. PLGA NPs encapsulating a low dose of DLX (DLX NPs) were synthesized and characterized and their localization was determined. The analgesic and anti-inflammatory effects of DLX NPs were evaluated in a spinal nerve ligation (SNL)-induced neuropathic pain model. The analgesic effect of DLX lasted for only a few hours and disappeared within 1 day. However, DLX NPs alleviated mechanical allodynia, and the effect was maintained for 1 week. DLX NPs were localized to the spinal microglia and suppressed microglial activation, phosphorylation of p38/NF-κB-mediated pathways and the production of inflammatory cytokines in the spinal dorsal horn of SNL rats. We demonstrated that DLX NPs can provide a prolonged analgesic effect by enhanced targeting of microglia. Our observations imply that DLX delivery through nanoparticle encapsulation allows drug repositioning with a prolonged analgesic effect, and reduces the potential side effects of abuse and overdose.

Histone demethylase AMX-1 is necessary for proper sensitivity to interstrand crosslink DNA damage

Histone methylation is dynamically regulated to shape the epigenome and adjust central nuclear processes including transcription, cell cycle control and DNA repair. Lysine-specific histone demethylase 2 (LSD2) has been implicated in multiple types of human cancers. However, its functions remain poorly understood. This study investigated the histone demethylase LSD2 homolog AMX-1 in C. elegans and uncovered a potential link between H3K4me2 modulation and DNA interstrand crosslink (ICL) repair. AMX-1 is a histone demethylase and mainly localizes to embryonic cells, the mitotic gut and sheath cells. Lack of AMX-1 expression resulted in embryonic lethality, a decreased brood size and disorganized premeiotic tip germline nuclei. Expression of AMX-1 and of the histone H3K4 demethylase SPR-5 is reciprocally up-regulated upon lack of each other and the mutants show increased H3K4me2 levels in the germline, indicating that AMX-1 and SPR-5 regulate H3K4me2 demethylation. Loss of AMX-1 function activates the CHK-1 kinase acting downstream of ATR and leads to the accumulation of RAD-51 foci and increased DNA damage-dependent apoptosis in the germline. AMX-1 is required for the proper expression of mismatch repair component MutL/MLH-1 and sensitivity against ICLs. Interestingly, formation of ICLs lead to ubiquitination-dependent subcellular relocalization of AMX-1. Taken together, our data suggest that AMX-1 functions in ICL repair in the germline.

Zwitterionic polydopamine coatings suppress silicone implant-induced capsule formation

A synthetic zwitterionic dopamine derivative (ZW-DOPA) containing both catechol and amine groups was recently shown to exhibit excellent antifouling activity on marine surfaces. Here, we have extended these analyses to investigate the effects of ZW-DOPA coating on silicone implants. Successful formation of ZW-DOPA coatings on silicone implants was confirmed based on a combination of decreased static water contact angles on silicone implants, evidence of new peaks at 400.2 (N 1s), 232.2 (S 2s), and 168.0 (S 2p) eV, and increased quantitative atomic composition of C 1s with a concurrent decrease of Si 2p. Anti-biofilm formation assays revealed that ZW-DOPA coating prevented biofilm formation on silicone at a non-lethal concentration (0.5 mg mL-1). Capsule formation was also significantly inhibited by ZW-DOPA coating in vivo and the differentiation of fibroblasts into myofibroblasts was significantly suppressed. Together, these data suggest that silicone implants coated with ZW-DOPA may prevent capsular contracture after insertion when used in breast surgery.

Evaluation of Sub-micrometer-Sized Particles Generated from a Diesel Locomotive and Jackleg Drilling in an Underground Metal Mine

Concerns have been raised regarding small respirable particles, i.e. sub-micrometer-sized particles, associated with mining activities. This evaluation was designed to investigate the emissions from jackleg drilling and diesel engines and to characterize the nature of emitted particles using gravimetric analysis and number metrics. The mass concentration to which workers are potentially exposed was determined from a 4-h sampling in the vicinity of drilling activities in an underground metal mine; this concentration was found to be lower than 0.6 mg m-3 of total respirable dust. This mass concentration is low; however, the number concentrations of emitted particles from drilling exceeded 1 × 106 particles cm-3 in areas 7-9 m downwind from the drilling operation. Sub-micrometer-sized particles were also observed in aerosol samples collected using a specialized sampler, and various elements associated with drilling were found among these emitted particles. Finally, the particles in the diesel exhaust were collected, and the exhaust was found to contain nanometer-sized particles.

Vitamin E reduces spasms caused by prenatal stress by lowering calpain expression

BACKGROUND

Prenatal stress increases the susceptibility of infants to seizures and is known to be associated with oxidative stress. Recent studies suggest that vitamin E has beneficial effects in various neurological diseases due to its antioxidant properties. In this study, we investigated the relationship between prenatal stress and vitamin E treatment on N-methyl-D-aspartate (NMDA)-induced spasms.

METHODS

We used pregnant female Sprague Dawley rats and induced prenatal stress with an injection of betamethasone on G15. They were then treated orally with 200 mg/kg vitamin E or saline twice a day from G15-G21. On postnatal day 15, NMDA was administered to trigger spasms in offspring. The total number of spasms and latency to the first spasm were recorded. We also measured oxidative stress in the medial cortex using western blot, and calpain activity, thiobarbituric acid reactive substances (TBARS), glutathione (GSH)/GSH/glutathione disulfide (GSSG), superoxide dismutase (SOD) activity, catalase activity, and nitric oxide (NO) assays.

RESULTS

We observed that rats treated with vitamin E while exposed to prenatal stress demonstrated reduced total number and frequency of spasms. Expression of glutamate decarboxylase 67 (GAD67) and K⁺/Cl^- co-transporter (KCC2) were reduced after prenatal stress; this recovered in the vitamin E treated group. Further, expression of calpain 2 was decreased and various markers of oxidative stress (malondialdehyde (MDA), GSH/GSSG, SOD, catalase, and NO) were reduced in the vitamin E treated group.

CONCLUSIONS

Our results provide evidence that vitamin E lowers oxidative stress and decreases seizure susceptibility in rat offspring exposed to prenatal stress. Given the well-known safety profile of vitamin E, these results indicate its potential as a strategy for preventing seizures.

TAP2, a peptide antagonist of Toll-like receptor 4, attenuates pain and cartilage degradation in a monoiodoacetate-induced arthritis rat model

Because inflammation in osteoarthritis (OA) is related to the Toll-like receptor 4 (TLR4) signaling cascades, TLR4 is a reasonable target for developing therapeutics for OA. Thus, we investigated whether TAP2, a peptide antagonist of TLR4, reduces the monoiodoacetate (MIA)-induced arthritic pain and cartilage degradation in rats. TLR4 expression of human OA chondrocytes and synoviocytes and the knee joint tissue of MIA-induced arthritis were evaluated. MIA-induced arthritic model using Sprague–Dawley rats (6 week-old-male) were treated with TAP2, a TLR4 antagonist, and evaluated with behavioral test, immunohistochemistry, and quantitative PCR. TLR4 was highly expressed in the knee joints of patients with OA and the MIA-induced rat model. Further, a single intraarticular injection of TAP2 (25 nmol/rat) molecules targeting TLR4 on day 7 after MIA injection dramatically attenuated pain behavior for about 3 weeks and reduced cartilage loss in the knee joints and microglial activation in the spinal dorsal horns. Likewise, the mRNA levels of TNFα and IL-1β, reactive oxygen species, and the expression of MMP13 in the knee joints of TAP2-treated rats was significantly decreased by TAP2 treatment compared with the control. Moreover, interestingly, the duration of OA pain relief by TAP2 was much longer than that of chemical TLR4 antagonists, such as C34 and M62812. In conclusion, TAP2 could effectively attenuate MIA-induced arthritis in rats by blocking TLR4 and its successive inflammatory cytokines and MMP13. Therefore, TAP2 could be a prospective therapeutic to treat patients with OA.

Traditional Korean herbal formulae, Yuk-Mi-Ji-Hwang-Tang, ameliorates impairment of hippocampal memory ability by chronic restraint stress of mouse model

ETHNOPHARMACOLOGICAL RELEVANCE

Yuk-Mi-Jihwang-Tang (YJT) has been popularly prescribed to treat aging related disorders over than hundreds of years in East Asia countries.

AIM OF THE STUDY

To investigate possible modulatory actions of YJT on chronic restraint stress (CRS)-induced neurodegeneration on hippocampus neuronal injuries.

MATERIALS AND METHODS

Mice were orally administered with YJT (100, 200, or 400 mg/kg) or ascorbic acid (100 mg/kg) before 4 h of stress for 28 days. Morris water maze task was completed from day 24th to 28th, and stress hormones and biochemical analyzes were measured.

RESULTS

Four weeks of the CRS abnormally affected memory impairments by measurement of escape latency and time spent in the target quadrant. Additionally, neurotransmitters were also drastically altered in serum or hippocampus protein levels by CRS. Gene expressions for 5-hydroxytryptamine (5-HT) receptor, 5-HT-transport, and tryptophan hydroxylase were also altered, whereas YJT led to normalize the above alterations. Additionally, YJT also beneficially worked on endogenous redox system as well as inflammatory reactions in the hippocampal neurons. We observed that hippocampal excitotoxicity was induced by CRS which were evidenced by depletion of phosphor-cAMP response element-binding protein, brain-derived neurotrophic factor, nuclear factor erythroid-2-related factor 2, heme oxygenase-1 and abnormally increases of acetylcholine esterase activities in hippocampus protein levels; however, YJT considerably improved the above pathological conditions.

CONCLUSIONS

Our findings supported YJT enhance memory function via regulation of hippocampal excitotoxicity-derived memory impairment, stress hormone, and endogenous redox, respectively.

p66shc siRNA-Encapsulated PLGA Nanoparticles Ameliorate Neuropathic Pain Following Spinal Nerve Ligation

p66shc, a member of the shc adaptor protein family, has been shown to participate in regulation of mitochondrial homeostasis, apoptosis, and autophagosome formation. The present study was performed to investigate whether p66shc siRNA-encapsulated poly(d,l-lactic-co-glycolic acid) nanoparticles (p66shc siRNA-PLGA NPs) can attenuate spinal nerve ligation (SNL)-induced neuropathic pain in rats. The SNL-induced pain behavior was decreased in the p66shc siRNA-PLGA NP-treated group compared with the scrambled siRNA-PLGA NP-treated group. In the L5 spinal cord of the p66shc siRNA-PLGA NP-treated group, expression levels of phosphorylated p66shc, cleaved caspase-3, p62, and PINK1, as well as microglial activation, were also decreased. In addition, p66shc knockdown using p66shc siRNA reduced the expression levels of cleaved caspase-3, p62, and PINK1, as well as proinflammatory mediators in the H₂O₂-treated HT22 neuronal cells. These results suggest that downregulation of p66shc expression in the spinal cord using p66shc siRNA-PLGA NPs could reduce the SNL-induced neuropathic pain by attenuating the SNL-induced aberrant autophagic, mitophagic, and neuroinflammatory processes in rats.

miRNA 146a-5p-loaded poly(d,l-lactic-co-glycolic acid) nanoparticles impair pain behaviors by inhibiting multiple inflammatory pathways in microglia

Aims: We investigated whether miRNA (miR) 146a-5p-loaded nanoparticles (NPs) can attenuate neuropathic pain behaviors in the rat spinal nerve ligation-induced neuropathic pain model by inhibiting activation of the NF-κB and p38 MAPK pathways in spinal microglia. Materials & methods: After NP preparation, miR NPs were assessed for their physical characteristics and then injected intrathecally into the spinal cords of rat spinal nerve ligation rats to test their analgesic effects. Results: miR NPs reduced pain behaviors for 11 days by negatively regulating the inflammatory response in spinal microglia. Conclusion: The anti-inflammatory effects of miR 146a-5p along with nanoparticle-based materials make miR NPs promising tools for treating neuropathic pain.

p66shc siRNA Nanoparticles Ameliorate Chondrocytic Mitochondrial Dysfunction in Osteoarthritis

Background

Osteoarthritis (OA) is the most common type of joint disease associated with cartilage breakdown. However, the role played by mitochondrial dysfunction in OA remains inadequately understood. Therefore, we investigated the role played by p66shc during oxidative damage and mitochondrial dysfunction in OA and the effects of p66shc downregulation on OA progression.

Methods

Monosodium iodoacetate (MIA), which is commonly used to generate OA animal models, inhibits glycolysis and biosynthetic processes in chondrocytes, eventually causing cell death. To observe the effects of MIA and poly(lactic-co-glycolic acid) (PLGA)-based nanoparticles, histological analysis, immunohistochemistry, micro-CT, mechanical paw withdrawal thresholds, quantitative PCR, and measurement of oxygen consumption rate and extracellular acidification rate were conducted.

Results

p-p66shc was highly expressed in cartilage from OA patients and rats with MIA-induced OA. MIA caused mitochondrial dysfunction and reactive oxygen species (ROS) production, and the inhibition of p66shc phosphorylation attenuated MIA-induced ROS production in human chondrocytes. Inhibition of p66shc by PLGA-based nanoparticles-delivered siRNA ameliorated pain behavior, cartilage damage, and inflammatory cytokine production in the knee joints of MIA-induced OA rats.

Conclusion

p66shc is involved in cartilage degeneration in OA. By delivering p66shc-siRNA-loaded nanoparticles into the knee joints with OA, mitochondrial dysfunction-induced cartilage damage can be significantly decreased. Thus, p66shc siRNA PLGA nanoparticles may be a promising option for the treatment of OA.

CR6 interacting factor 1 deficiency induces premature senescence via SIRT3 inhibition in endothelial cells

Vascular endothelial cell senescence is an important cause of cardiac-related diseases. Mitochondrial reactive oxygen species (mtROS) have been implicated in cellular senescence and multiple cardiovascular disorders. CR6 interacting factor 1 (CRIF1) deficiency has been shown to increase mtROS via the inhibition of mitochondrial oxidative phosphorylation; however, the mechanisms by which mtROS regulates vascular endothelial senescence have not been thoroughly explored. The goal of this study was to investigate the effects of CRIF1 deficiency on endothelial senescence and to elucidate the underlying mechanisms. CRIF1 deficiency was shown to increase the activity of senescence-associated β-galactosidase along with increased expression of phosphorylated p53, p21, and p16 proteins. Cell cycle arrested in the G0/G1 phase were identified in CRIF1-deficient cells using the flow cytometry. Furthermore, CRIF1 deficiency was also shown to increase cellular senescence by reducing the expression of Sirtuin 3 (SIRT3) via ubiquitin-mediated degradation of transcription factors PGC1α and NRF2. Downregulation of CRIF1 also attenuated the function of mitochondrial antioxidant enzymes including manganese superoxide dismutase (MnSOD), Foxo3a, nicotinamide-adenine dinucleotide phosphate, and glutathione via the suppression of SIRT3. Interestingly, overexpression of SIRT3 in CRIF1-deficient endothelial cells not only reduced mtROS levels by elevating expression of the antioxidant enzyme MnSOD but also decreased the expression of cell senescence markers. Taken together, these results suggest that CRIF1 deficiency induces vascular endothelial cell senescence via ubiquitin-mediated degradation of the transcription coactivators PGC1α and NRF2, resulting in decreased expression of SIRT3.

BMAL1 Suppresses Proliferation, Migration, and Invasion of U87MG Cells by Downregulating Cyclin B1, Phospho-AKT, and Metalloproteinase-9

Several studies have shown that brain and muscle aryl hydrocarbon receptor nuclear translocator-like 1 (BMAL1), an important molecule for maintaining circadian rhythms, inhibits the growth and metastasis of tumor cells in several types of cancer, including lung, colon, and breast cancer. However, its role in glioblastoma has not yet been established. Here, we addressed the function of BMAL1 in U87MG glioblastoma cells with two approaches-loss and gain of function. In the loss of function experiments, cell proliferation in U87MG cells transfected with small interfering RNA (siRNA) targeting BMAL1 was increased by approximately 24% (small interfering (si)-NC 0.91 ± 0.00 vs. si-BMAL1 1.129 ± 0.08) via upregulation of cyclin B1. In addition, cell migration and invasion of BMAL1 siRNA-treated glioblastoma cells were elevated by approximately 20% (si-NC 51.00 ± 1.53 vs. si-BMAL161.33 ± 0.88) and 209% (si-NC 21.28 ± 1.37 vs. si-BMAL1 44.47 ± 3.48), respectively, through the accumulation of phosphorylated-AKT (p-AKT) and matrix metalloproteinase (MMP)-9. Gain of function experiments revealed that adenovirus-mediated ectopic expression of BMAL1 in U87MG cells resulted in a 19% (Adenovirus (Ad)-vector 0.94± 0.03 vs. Ad-BMAL1 0.76 ± 0.03) decrease in cell proliferation compared with the control via downregulation of cyclin B1 and increased early and late apoptosis due to changes in the levels of BCL2-associated X protein (BAX), B-cell lymphoma 2 (BCL-2), and cleaved caspase-3. Likewise, cell migration and invasion were attenuated by approximately 24% (Ad-vector 55.00 ± 0.00 vs. Ad-BMAL1 41.83 ± 2.90) and 49% (Ad-vector 70.01 ± 1.24 vs. Ad-BMAL1 35.55 ± 1.78), respectively, in BMAL1-overexpressing U87MG cells following downregulation of p-AKT and MMP-9. Taken together, our results suggest that BMAL1 acts as an anti-cancer gene by altering the proliferation, migration, and invasion of glioblastoma cells. Therefore, the BMAL1 gene could be a potential therapeutic target in the treatment of glioblastoma.

p47phox siRNA-Loaded PLGA Nanoparticles Suppress ROS/Oxidative Stress-Induced Chondrocyte Damage in Osteoarthritis

Osteoarthritis (OA) is the most common joint disorder that has had an increasing prevalence due to the aging of the population. Recent studies have concluded that OA progression is related to oxidative stress and reactive oxygen species (ROS). ROS are produced at low levels in articular chondrocytes, mainly by the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, and ROS production and oxidative stress have been found to be elevated in patients with OA. The cartilage of OA-affected rat exhibits a significant induction of p47phox, a cytosolic subunit of the NADPH oxidase, similarly to human osteoarthritis cartilage. Therefore, this study tested whether siRNA p47phox that is introduced with poly (D,L-lactic-co-glycolic acid) (PLGA) nanoparticles (p47phox si_NPs) can alleviate chondrocyte cell death by reducing ROS production. Here, we confirm that p47phox si_NPs significantly attenuated oxidative stress and decreased cartilage damage in mono-iodoacetate (MIA)-induced OA. In conclusion, these data suggest that p47phox si_NPs may be of therapeutic value in the treatment of osteoarthritis.