Mouse B1 Research Articles

Vitamin U alleviates AFB1-induced hepatotoxicity in pregnant and lactating mice by regulating the Nrf2/Hmox1 pathway

This study investigated the protective effect of Vitamin U on liver injury induced by aflatoxin B1 (AFB1) in maternal mice. 25 pregnant ICR mice were randomly divided into five groups: the AFB1 group (AF, 0.3 mg AFB1/kg b.w.), the Vitamin U group (U, 50 mg Vitamin U/kg b.w.), the AFB1 + Vitamin U group (AU, 50 mg Vitamin U /kg b.w. + 0.3 mg AFB1/kg b.w.), the control group (DMSO), and the MOCK group (distilled water). They were administered substances by gavage every day for 28 days. Results indicated that exposure to AFB1 increased the liver index and caused histological disruptions. Elevated serum levels of ALT and ALP were observed, along with a significant increase in liver MDA content and a decrease in GSH-Px and T-SOD levels. Moreover, the Keap1 and Hmox1 gene was downregulated with statistical significance, while the IL1β and TNFα gene were significantly upregulated. Vitamin U was demonstrated by the organized structure of liver cells in tissue slices, effectively reducing liver cell necrosis. This intervention was associated with a significant decrease in serum ALT and ALP activities, as well as a significant decrease in liver MDA content. Additionally, there were significant increases in liver T-SOD and GSH-Px levels, along with upregulation of mRNA and protein expression of Nfr2, Hmox1 and Keap1, and downregulation of mRNA expression of the IL1β gene. In summary, Vitamin U mitigated oxidative stress-induced liver injury by modulating the Nrf2/Hmox1 signaling pathway and inflammatory factors affected by AFB1.

Bifidobacterium breve alleviates gut–liver-axis injury caused by high-fat diet and aflatoxin B1 in mice

<em>Bifidobacterium breve</em> alleviates gut&amp;ndash;liver-axis injury caused by high-fat diet and aflatoxin B1 in mice

Hesperetin protects hippocampal neurons from the neurotoxicity of Aflatoxin B1 in mice

Aflatoxin B1 (AFB1) is a major food and feed pollutant that endangers public health. Previous studies have shown that exposure to AFB1 causes neurotoxicity in the body. However, the mechanism of neurotoxicity caused by AFB1 is not well understood, and finding a workable and practical method to safeguard animals from AFB1 toxicity is essential. This study confirmed that AFB1 caused endoplasmic reticulum stress (ER stress) and apoptosis in hippocampal neurons using C57BL/6 J mice and HT22 cells as models. In vitro experiments showed that the aryl hydrocarbon receptor (AHR) plays a significant role in the cytotoxicity of AFB1. Finally, we assessed how hesperetin protecting against the neurotoxicity caused by AFB1. Our findings demonstrated that AFB1 increased the levels of BAX and Cleaved-Caspase3 proteins, while decreasing the levels of BCL2 protein in the CA1 and CA3 regions of the hippocampus. The AFB1 increased the expression of AHR and activated nuclear translocation. It also elevated the expression levels of Chop, GRP78, p-IRE1/ Xbp1s, and p-PERK/p-EIF2a. Importantly, we also discovered for the first time that blocking AHR in HT22 cells dramatically reduced the level of ER stress and apoptosis caused by AFB1. In vivo and in vitro studies, supplementation of hesperetin effectively reversed AFB1-induced cytotoxicity. We have demonstrated that hesperetin effectively restored the imbalance in the GSH/GST system in HT22 cells treated with AFB1. Furthermore, we observed that elevated GSH levels facilitated the formation of AFB1-GSH complexes, which enhanced the excretion of AFB1. Therefore, hesperetin improves ER stress-induced apoptosis by reducing AFB1 activation of AHR.

4.5SH RNA counteracts deleterious exonization of SINE B1 in mice

4.5SH RNA is a highly abundant, small rodent-specific noncoding RNA that localizes to nuclear speckles enriched in pre-mRNA-splicing regulators. To investigate the physiological functions of 4.5SH RNA, we have created mutant mice that lack the expression of 4.5SH RNA. The mutant mice exhibited embryonic lethality, suggesting that 4.5SH RNA is an essential species-specific noncoding RNA in mice. RNA-sequencing analyses revealed that 4.5SH RNA protects the transcriptome from abnormal exonizations of the antisense insertions of the retrotransposon SINE B1 (asB1), which would otherwise introduce deleterious premature stop codons or frameshift mutations. Mechanistically, 4.5SH RNA base pairs with complementary asB1-containing exons via the target recognition region and recruits effector proteins including Hnrnpm via its 5' stem loop region. The modular organization of 4.5SH RNA allows us to engineer a programmable splicing regulator to induce the skipping of target exons of interest. Our results also suggest the general existence of splicing regulatory noncoding RNAs.

Mouse B2 SINE elements function as IFN-inducible enhancers.

Regulatory networks underlying innate immunity continually face selective pressures to adapt to new and evolving pathogens. Transposable elements (TEs) can affect immune gene expression as a source of inducible regulatory elements, but the significance of these elements in facilitating evolutionary diversification of innate immunity remains largely unexplored. Here, we investigated the mouse epigenomic response to type II interferon (IFN) signaling and discovered that elements from a subfamily of B2 SINE (B2_Mm2) contain STAT1 binding sites and function as IFN-inducible enhancers. CRISPR deletion experiments in mouse cells demonstrated that a B2_Mm2 element has been co-opted as an enhancer driving IFN-inducible expression of Dicer1. The rodent-specific B2 SINE family is highly abundant in the mouse genome and elements have been previously characterized to exhibit promoter, insulator, and non-coding RNA activity. Our work establishes a new role for B2 elements as inducible enhancer elements that influence mouse immunity, and exemplifies how lineage-specific TEs can facilitate evolutionary turnover and divergence of innate immune regulatory networks.

Artificial Diets with Altered Levels of Sulfur Amino Acids Induce Anticancer Activity in Mice with Metastatic Colon Cancer, Ovarian Cancer and Renal Cell Carcinoma.

Sulfur-containing amino acids methionine (Met), cysteine (Cys) and taurine (Tau) are common dietary constituents with important cellular roles. Met restriction is already known to exert in vivo anticancer activity. However, since Met is a precursor of Cys and Cys produces Tau, the role of Cys and Tau in the anticancer activity of Met-restricted diets is poorly understood. In this work, we screened the in vivo anticancer activity of several Met-deficient artificial diets supplemented with Cys, Tau or both. Diet B1 (6% casein, 2.5% leucine, 0.2% Cys and 1% lipids) and diet B2B (6% casein, 5% glutamine, 2.5% leucine, 0.2% Tau and 1% lipids) showed the highest activity and were selected for further studies. Both diets induced marked anticancer activity in two animal models of metastatic colon cancer, which were established by injecting CT26.WT murine colon cancer cells in the tail vein or peritoneum of immunocompetent BALB/cAnNRj mice. Diets B1 and B2B also increased survival of mice with disseminated ovarian cancer (intraperitoneal ID8 Tp53-/- cells in C57BL/6JRj mice) and renal cell carcinoma (intraperitoneal Renca cells in BALB/cAnNRj mice). The high activity of diet B1 in mice with metastatic colon cancer may be useful in colon cancer therapy.

Regulation of the immune system by administering lactic acid bacteria to suppress the effects of aflatoxin B1 in mice (Mus musculus)

Regulation of the immune system by administering lactic acid bacteria to suppress the effects of aflatoxin B1 in mice (Mus musculus)

V‐ATPase Domain Assembly is Increased in Ncoa7 KO Mice

The V‐ATPase is a multisubunit, transmembrane proton pump that generates electrochemical gradients across membranes driving essential cell biological processes. Critically, for proton pumping activity, the two distinct domains of the V‐ATPase (V1 and VO) must assemble into a functional holoenzyme. The kidney‐specific V‐ATPase is expressed in intercalated cells (ICs), which regulate acid‐base homeostasis by adjusting the number of apical V‐ATPase holoenzymes via regulated trafficking. Thus, V‐ATPase dysfunction in ICs leads to distal renal tubular acidosis (dRTA), which is characterized by an accumulation of acid in the blood. Despite this, little is known about the molecular regulation of the kidney V‐ATPase.We recently identified a new class of V‐ATPase interacting proteins defined by their TLDc domain which protect against oxidative stress (Ncoa7, Oxr1, Tbc1d24, Tldc1, Tldc2). We showed that the purified TLDc domains of Ncoa7, Oxr1, and Tldc2 interact with the IC‐specific B1 subunit of the V‐ATPase. Furthermore, endogenous Ncoa7, Oxr1, and Tbc1d24 interacted with the B1 subunit. Endogenous Tldc1 or Tldc2 were expressed at low levels in the kidney, but proteins overexpressed in cell cultures interacted with the B1 V‐ATPase from kidney lysates. Of importance, Ncoa7 knockout (KO) mice had decreased V‐ATPase expression in ICs and developed dRTA, which led us to hypothesize that the TLDc proteins regulate the kidney V‐ATPase.Here, we asked whether Ncoa7 deletion affected apical trafficking of the V‐ATPase or assembly of the V1 and VO domains into a holoenzyme in renal ICs after stimulation of proton secretion. Wild type (WT) and Ncoa7 KO mice were injected with CPT‐cAMP, to stimulate proton secretion, or saline as a control. Localization of the B1 and a4 subunits was visualized in ICs by immunofluorescence using specific antibodies, and apical accumulation was quantified by line intensity scanning. Our results show that cAMP significantly increased apical accumulation of B1 and a4 in WT mice from 55% to 78% of the cellular total, as expected. However, ICs in the Ncoa7 KO mice were already highly activated at baseline, with only a slight trend towards increased apical accumulation of the V‐ATPase after cAMP treatment (79% to 82%). A Pearson’s correlation analysis of the colocalization of B1 and a4, as a measure of V‐ATPase assembly, revealed a significant increase in assembly in Ncoa7 KO mice, relative to control animals, after both saline and cAMP treatment. Furthermore, a Proximity Ligation Assay also showed a marked increase in assembly of the V‐ATPase in untreated Ncoa7 KO ICs compared to control WT mice.These data suggest that loss of Ncoa7 does not affect apical accumulation of the V‐ATPase in ICs. Ncoa7 KO mice ICs are already highly activated in untreated mice. This is probably a compensatory response to the prevailing acidosis observed in these mice, which may be due to decreased total V‐ATPase protein expression in their ICs. Our data shows, however, increased assembly of the remaining V‐ATPase in Ncoa7 KO mice. Thus, we conclude that Ncoa7 is part of a regulatory mechanism that inhibits assembly of the V‐ATPase into a holoenzyme in WT mice, while not affecting trafficking of V‐ATPase subunits to the apical surface. How this negative effect is balanced in vivo to determine the overall degree of V‐ATPase holoenzyme assembly remains to be determined.

BHPF exposure impairs mouse and human decidualization

Although BHPF has been widely used in plastic manufacturing as a substitute for BPA, current evidence suggests that BHPF also causes harmful effects on reproduction. However, effects of BHPF on mammalian early pregnancy are still poorly defined. This study aimed to explore the effects of BHPF on early pregnancy, especially decidualization and embryonic development in mice and human beings. The results showed that 50 and 100 mg/kg BHPF exposure reduced birth weight, and implantation site weight on the day 8 of pregnancy in mice. Because BHPF inhibits both embryo development and artificial decidualization in mice, suggesting that the detrimental effects of BHPF should be from its effects on embryo development and decidualization. Under in vitro decidualization, 10 μM BHPF inhibits decidualization and leads to disordered expression of Lamin B1 and collagen in mice. In addition, 10 μM BHPF also inhibits decidualization, and causes disordered expression of both collagen III and Lamin B1 under human in vitro decidualization. However, collagen III supplementation can rescue BHPF inhibition on decidualization. Further, our study demonstrates that BHPF impairs human decidualization through the HB-EGF/EGFR/STAT3/Collagen III pathway. Taken together these data suggest that exposure to BHPF impairs mouse and human decidualization during early pregnancy.

In vitro pharmacological profile of PHA-022121, a small molecule bradykinin B2 receptor antagonist in clinical development

PHA-022121 is a novel small molecule bradykinin B2 receptor antagonist, in clinical development for the treatment and prevention of hereditary angioedema attacks. The present study describes the in vitro pharmacological characteristics of PHA-022121 and its active metabolite, PHA-022484 (M2-D). In mammalian cell lines, PHA-022121 and PHA-022484 show high affinity for the recombinant human bradykinin B2 receptor with Ki values of 0.47 and 0.70 nM, respectively, and potent antagonism of the human bradykinin B2 receptor with Kb values of 0.15 and 0.26 nM, respectively (calcium mobilization assay). Antagonist potency at the recombinant cynomolgus monkey bradykinin B2 receptor is similarly high (Kb values of 1.42 and 1.12 nM for PHA-022121 and PHA-022484, respectively), however, potency at rat, mouse, rabbit and dog bradykinin B2 receptors is at least 100-fold lower than the potency at the human receptor for both compounds. In the human umbilical vein contractility assay, both PHA-022121 and PHA-022484 show a potent, surmountable and reversible B2 antagonist activity with pA2 values of 0.35 and 0.47 nM, respectively. The in vitro off-target profile of PHA-022121 and PHA-022484 demonstrates a high degree of selectivity over a wide range of molecular targets, including the bradykinin B1 receptor.It is concluded that PHA-022121 is a novel, low-molecular weight, competitive antagonist of the human bradykinin B2 receptor with high affinity, high antagonist potency, and high selectivity. It is about 20-fold more potent than icatibant at the human bradykinin B2 receptor as assessed using recombinant or endogenously expressed receptors.

Intrathymic differentiation of natural antibody-producing plasma cells in human neonates

The thymus is a central lymphoid organ primarily responsible for the development of T cells. A small proportion of B cells, however, also reside in the thymus to assist negative selection of self-reactive T cells. Here we show that the thymus of human neonates contains a consistent contingent of CD138+ plasma cells, producing all classes and subclasses of immunoglobulins with the exception of IgD. These antibody-secreting cells are part of a larger subset of B cells that share the expression of signature genes defining mouse B1 cells, yet lack the expression of complement receptors CD21 and CD35. Data from single-cell transcriptomic, clonal correspondence and in vitro differentiation assays support the notion of intrathymic CD138+ plasma cell differentiation, alongside other B cell subsets with distinctive molecular phenotypes. Lastly, neonatal thymic plasma cells also include clones reactive to commensal and pathogenic bacteria that commonly infect children born with antibody deficiency. Thus, our findings point to the thymus as a source of innate humoral immunity in human neonates.

Effects of Red Cabbage and Garlic Extracts on Oxidative Stress Induced by Fumonisin B1

This study was designed to investigate the protective effects of red cabbage and garlic extracts on the oxidative stress induced through treatment with fumonisin B1 in male mice. The study was conducted on sixty male mice that were divided randomly into six groups. Group 1included control mice, mice in group 2 received a daily oral dose (200 µg/kg.b.w) of fumonisin B1 for one month to induced mycotoxicosis, mice in group 3 received 500 mg/kg.b.w red cabbage extract plus fumonisin B1, mice in group 4 received only red cabbage extract, mice in group 5 received 500 mg/kg.b.w garlic extract plus fumonisin B1, and group 6 received garlic extract alone. After finishing the experiments, samples of blood were used for biochemical examination. The results indicated that group 2 mice had significantly increased (p &lt; 0.05) serum levels of malondialdehyde, which is a biomarker of lipid peroxidation, in addition to significantly decreased levels of catalase and the antioxidant enzymes glutathione peroxidase , glutathione , and superoxide dismutase , as compared to the normal control group. Oral administration of garlic and red cabbage extracts produced significantly decreased levels of serum malondialdehyde and significantly increased levels of superoxide dismutase, catalase, glutathione peroxidase, and glutathione, as compared to group 2. These results indicated that the experimental treatment with fumonisin B-1 caused an elevated oxidative stress in addition to the consumption of the antioxidant enzymes in response to the induced oxidative aggression.

MiR-29a/b1 Regulates the Luteinizing Hormone Secretion and Affects Mouse Ovulation

miR-29a/b1 was reportedly involved in the regulation of the reproductive function in female mice, but the underlying molecular mechanisms are not clear. In this study, female mice lacking miR-29a/b1 showed a delay in vaginal opening, irregular estrous cycles, ovulation disorder and subfertility. The level of luteinizing hormone (LH) was significantly lower in plasma but higher in pituitary of mutant mice. However, egg development was normal in mutant mice and the ovulation disorder could be rescued by the superovulation treatment. These results suggested that the LH secretion was impaired in mutant mice. Further studies showed that deficiency of miR-29a/b1 in mice resulted in an abnormal expression of a number of proteins involved in vesicular transport and exocytosis in the pituitary, indicating the mutant mice had insufficient LH secretion. However, the detailed mechanism needs more research.

The toxicity of fumonisin B1on some biochemical and immunological parameters and its detoxification by red cabbage and garlic

The protective effects of red cabbage and garlic extracts against liver, kidney and thyroid gland damage induced by fumonisin B1 (FB1) in male mice were studied. Sixty mice divided in to six groups. Group one are the healthy mice, Group two are mice that received a daily oral dose of only FB-1 (100 µg/kg.b.w) for 1 month, Group three: are mice that received red cabbage extract (500 mg/kg.bw) plus FB1, Group four: are mice that received red cabbage extracts, Group five: are mice that received garlic extract (500mg/kg.bw) plus FB1, group 6:are mice that received only garlic extract. After finishing the experiments, samples of blood were used for biochemical examination. The results indicated that group (2) mice treated with fumonisin B1 had significantly increased levels of immunoglobulins (IgG and IgM), kidney function parameters (urea and creatinine), proteins (albumin and total protein (TP)), and thyroid hormones (T3 and T4), along with significantly decreased level of TSH (p &lt; 0.05). In the LD50 experiment, we are choose concentration (100 µg/kg.b.w) gavage to the mice. Oral administration red cabbage garlic extracts produced significantl reduction the levels serum IgG, IgM, T3, T4, urea, creatinine, TP and albumin and with a significant increase in TSH.

Forkhead box protein O1 (FoxO1)/SERPINB1 ameliorates ROS production in diabetic nephropathy.

With the increasing prevalence of diabetes in recent years, diabetic nephropathy (DN) has become a severe disease that greatly threatens human health. DN not only is a common complication of diabetes, but also takes an important place in kidney disease. To this end, the present study was designed to explore the effects of Forkhead box protein O1 (FoxO1) on reactive oxygen species (ROS) production in DN mice. DN mice were treated with recombinant protein of FoxO1. Afterward, inflammation ELISA kits were used to measure the levels of TNF‐α, IL‐1β, IL‐6, and IL‐18. The levels of MDA, SOD, GSH, and GSH‐PX were measured using kits according to the manufacturer's instructions. In addition, the production of ROS was assessed. Interestingly, the expression of FoxO1 was down‐regulated in DN mice. The treatment of FoxO1 recombinant protein ameliorated MDA levels, increased the levels of SOD, GSH, and GSH‐PX, and induced both mRNA and protein expression of hepatic serine protease inhibitor B1 (serpinB1) in ND mice. Similarly, FoxO1 reduced MDA levels and ROS production, increased the levels of SOD, GSH, and GSH‐PXs, and induced the mRNA and protein expression of serpinB1 in in vitro model of DN. The inhibition of serpinB1 attenuated the effects of FoxO1 on ROS production‐induced oxidative stress in in vitro model of DN. Overall, FoxO1/SERPINB1 ameliorated ROS production‐induced oxidative stress in DN.

Protective effect of red cabbage and garlic extracts against Fumonisin B1 induced hepatotoxicity in male mice

Red cabbage and garlic extracts have protective effect against liver damage induced by fumonisin B1 (FB1) in male mice was studied. Randomly sixty mice have been divided in to six groups. Group one are the healthy mice, Group two are mice received oral dose of only FB-1 (100 μg/kg.b.w) once on daily for 1 month, Group three: mice received with red cabbage extract (500 mg/kg.bw) plus FB1, Group four: mice receiving just red cabbage extracts, Group five: mice receiving garlic extract (500mg/kg.bw) plus FB1, group 6: mice received only garlic extract. After finished the experiment, samples of blood were used for biochemical examination. The results indicated that group (2) mice treated with Fumonisin B1 had significant increased (p less than 0.05) regarding the liver enzymes namely LDH, ALP, AST, GGT, as well as ALT and also in this work there has been significant increase (p less than 0.05) in lipid profile, T.ch, TG, HDL, VLDL but significantly decrease in reduction of LDL. Oral administration related to red cabbage as well as the garlic extracts produced significantly reducing the level related to serum of the VLDL, TG, LDH, ALP, AST, ALP, GGT, T.ch, ALT as well as HDL and cause increase significant in LDL.

SIRPα on Mouse B1 Cells Restricts Lymphoid Tissue Migration and Natural Antibody Production.

The inhibitory immunoreceptor SIRPα is expressed on myeloid and neuronal cells and interacts with the broadly expressed CD47. CD47-SIRPα interactions form an innate immune checkpoint and its targeting has shown promising results in cancer patients. Here, we report expression of SIRPα on B1 lymphocytes, a subpopulation of murine B cells responsible for the production of natural antibodies. Mice defective in SIRPα signaling (SIRPαΔCYT mice) displayed an enhanced CD11b/CD18 integrin-dependent B1 cell migration from the peritoneal cavity to the spleen, local B1 cell accumulation, and enhanced circulating natural antibody levels, which was further amplified upon immunization with T-independent type 2 antigen. As natural antibodies are atheroprotective, we investigated the involvement of SIRPα signaling in atherosclerosis development. Bone marrow (SIRPαΔCYT>LDLR−/−) chimaeric mice developed reduced atherosclerosis accompanied by increased natural antibody production. Collectively, our data identify SIRPα as a unique B1 cell inhibitory receptor acting to control B1 cell migration, and imply SIRPα as a potential therapeutic target in atherosclerosis.

In Vitro Pharmacological Profile of a New Small Molecule Bradykinin B2 Receptor Antagonist.

We here report the discovery and early characterization of Compound 3, a representative of a novel class of small molecule bradykinin (BK) B2 receptor antagonists, and its superior profile to the prior art B2 receptor antagonists Compound 1 and Compound 2. Compound 3, Compound 2, and Compound 1 are highly potent antagonists of the human recombinant B2 receptor (Kb values 0.24, 0.95, and 1.24 nM, respectively, calcium mobilization assay). Compound 3 is more potent than the prior art compounds and icatibant in this assay (Kb icatibant 2.81 nM). The compounds also potently inhibit BK-induced contraction of endogenous B2 receptors in a human isolated umbilical vein bioassay. The potencies of Compound 3, Compound 2, Compound 1, and icatibant are (pA2 values) 9.67, 9.02, 8.58, and 8.06 (i.e. 0.21, 0.95, 2.63, and 8.71 nM), respectively. Compound 3 and Compound 2 were further characterized. They inhibit BK-induced c-Fos signaling and internalization of recombinant human B2 receptors in HEK293 cells, and do not antagonize the venous effects mediated by other G protein-coupled receptors in the umbilical vein model, including the bradykinin B1 receptor. Antagonist potency of Compound 3 at cloned cynomolgus monkey, dog, rat, and mouse B2 receptors revealed species selectivity, with a high antagonist potency for human and monkey B2 receptors, but several hundred-fold lower potency for the other B2 receptors. The in vitro off-target profile of Compound 3 demonstrates a high degree of selectivity over a wide range of molecular targets, including the bradykinin B1 receptor. Compound 3 showed a lower intrinsic clearance in the microsomal stability assay than the prior art compounds. With an efflux ratio of 1.0 in the Caco-2 permeability assay Compound 3 is predicted to be not a substrate of efflux pumps. In conclusion, we discovered a novel chemical class of highly selective and very potent B2 receptor antagonists, as exemplified by Compound 3. The compound showed excellent absorption in the Caco-2 assay, predictive of good oral bioavailability, and favourable metabolic stability in liver microsomes. Compound 3 has provided a significant stepping stone towards the discovery of the orally bioavailable B2 antagonist PHA-022121, currently in phase 1 clinical development.

Circular RNA NF1-419 enhances autophagy to ameliorate senile dementia by binding Dynamin-1 and Adaptor protein 2 B1 in AD-like mice.

Recent studies have demonstrated circular RNAs (circRNAs) to be widely expressed and to have important physiological functions. However, the expression, regulation, and function of circRNAs in neuroglial cells are unknown. Herein, we characterized the expression, regulation, and function of circRNAs in astrocytes. Astrocyte circRNAs were identified by computational analysis of newborn SD rat primary astrocytes cultured with 20 g/L D-galactose. In this manner, 7376 circRNAs were identified, among which most circRNAs (5754) were derived from annot_exons, whereas 27 were antisense, 853 were exon/intron, 329 were intergenic, 41 were intronic, and 372 were one exon. Among these, circNF1-419 was demonstrated to regulate autophagy, in over-expressing circNF1-419 transfected astrocytes, through the PI3K-I/Akt-AMPK-mTOR and PI3K-I/Akt-mTOR signaling pathways. An adenovirus associated virus packaging system (virus titer 1 ×1012), over-expressing circNF1-419 and injected into mouse cerebral cortex, showed autophagy enhancing activity by binding the proteins Dynamin-1 and Adaptor protein 2 B1 (AP2B1). This binding regulated aging markers (p21, p35/25, and p16) and inflammatory factors (TNF-α and NF-κB), and reduced the expression of Alzheimer’s disease marker proteins (Tau, p-Tau, Aβ1-42, and APOE), which delayed senile dementia. Transcriptome analysis of the brain showed that circNF1-419 improved other signaling pathways, especially those related to the synapses of SAMP8 mice. These findings provide novel insights into circNF1-419 and its potential usefulness for the diagnosis and treatment of dementia by regulating Dynamin-1 and AP2B1 mediated autophagy.

Rapamycin-Loaded Biomimetic Nanoparticles Reverse Vascular Inflammation.

Through localized delivery of rapamycin via a biomimetic drug delivery system, it is possible to reduce vascular inflammation and thus the progression of vascular disease. Use biomimetic nanoparticles to deliver rapamycin to the vessel wall to reduce inflammation in an in vivo model of atherosclerosis after a short dosing schedule. Biomimetic nanoparticles (leukosomes) were synthesized using membrane proteins purified from activated J774 macrophages. Rapamycin-loaded nanoparticles were characterized using dynamic light scattering and were found to have a diameter of 108±2.3 nm, a surface charge of -15.4±14.4 mV, and a polydispersity index of 0.11 +/ 0.2. For in vivo studies, ApoE-/- mice were fed a high-fat diet for 12 weeks. Mice were injected with either PBS, free rapamycin (5 mg/kg), or rapamycin-loaded leukosomes (Leuko-Rapa; 5 mg/kg) once daily for 7 days. In mice treated with Leuko-Rapa, flow cytometry of disaggregated aortic tissue revealed fewer proliferating macrophages in the aorta (15.6±9.79 %) compared with untreated mice (30.2±13.34 %) and rapamycin alone (26.8±9.87 %). Decreased macrophage proliferation correlated with decreased levels of MCP (monocyte chemoattractant protein)-1 and IL (interleukin)-b1 in mice treated with Leuko-Rapa. Furthermore, Leuko-Rapa-treated mice also displayed significantly decreased MMP (matrix metalloproteinases) activity in the aorta (mean difference 2554±363.9, P=9.95122×10-6). No significant changes in metabolic or inflammation markers observed in liver metabolic assays. Histological analysis showed improvements in lung morphology, with no alterations in heart, spleen, lung, or liver in Leuko-Rapa-treated mice. We showed that our biomimetic nanoparticles showed a decrease in proliferating macrophage population that was accompanied by the reduction of key proinflammatory cytokines and changes in plaque morphology. This proof-of-concept showed that our platform was capable of suppressing macrophage proliferation within the aorta after a short dosing schedule (7 days) and with a favorable toxicity profile. This treatment could be a promising intervention for the acute stabilization of late-stage plaques.