[Transcriptome data mining combined with clinical and animal experiments for identification of syndrome element marker genes during entire course of steroid-induced osteonecrosis of femoral head].

A research strategy combining transcriptome data mining and experimental verification was adopted to identify the marker genes characterizing the syndrome elements of phlegm, stasis, and deficiency in steroid-induced osteonecrosis of the femoral head(SONFH). Firstly, the common differentially expressed gene sets of SONFH with the syndromes of phlegm-stasis obstructing collaterals, vessel obstruction, and liver-kidney deficiency were obtained from the clinical transcriptomic analysis of a previous study. The differential expression trend analysis and functional gene mining were then employed to predict the candidate marker gene sets representing phlegm, stasis, and deficiency. The whole blood samples from SONFH patients, whole blood samples from SONFH rats, and affected femoral head tissue samples were collected for qPCR, which aimed to determine the expression levels of the candidate marker genes mentioned above. Furthermore, the receiver operating characteristic curve(ROC) was established to objectively evaluate the syndrome differentiation effectiveness of the candidate marker genes mentioned above. The transcriptome data analysis results showed that the candidate marker genes for phlegm was ELOVL fatty acid elongase 6(ELOVL6), and those for stasis were ankyrin 1(ANK1), glycophorin A/B(GYPA/B), and Rh-associated glycoprotein(RHAG). The candidate marker genes for deficiency were solute carrier family 2 member 1(SLC2A1) and stomatin(STOM). The qPCR results showed that compared with that in the non-SONFH group, ELOVL6 had the lowest expression level in the peripheral blood of the SONFH patients with the syndrome of phlegm-stasis obstructing collaterals(P<0.05). Compared with that in the normal control group, ELOVL6 had the lowest expression level in the peripheral blood and affected femoral head tissue of SONFH rats modeled for 4 weeks(P<0.01), and it showed better syndrome differentiation effectiveness of rats modeled for 4 weeks(AUC=0.850, P=0.006) than at other modeling time points(8, 12, 16, and 21 weeks, AUC of 0.689, 0.766, 0.588, and 0.662, respectively). Compared with that in the non-SONFH group, the expression levels of ANK1, GYPA, and RHAG were the lowest in the peripheral blood of SONFH patients with the vessel obstruction syndrome(P<0.05). The expression levels of the three genes were the lowest in the peripheral blood and affected femoral head tissue of SONFH rats modeled for 12 weeks(P<0.05, P<0.01), and their syndrome differentiation effectiveness in the rats modeled for 12 weeks(GYPA: AUC=0.861, P=0.012; ANK1: AUC=0.855, P=0.006; RHAG: AUC=0.854, P=0.009) was superior to that for 4, 8, 16, and 21 weeks(GYPA: AUC=0.646, 0.573, 0.691, and 0.617, respectively; ANK: AUC1=0.630, 0.658, 0.657, and 0.585, respectively; RHAG: AUC=0.592, 0.511, 0.515, and 0.536, respectively). Compared with the non-SONFH group, both SLC2A1 and STOM had the lowest expression levels in the peripheral blood of patients with the syndrome of liver and kidney deficiency(P<0.05). Compared with the normal control group, their expression levels were the lowest in the peripheral blood and affected femoral head tissue of SONFH rats modeled for 21 weeks(P<0.05, except STOM in the peripheral blood of rats). Moreover, the syndrome differentiation effectiveness of SLC2A1 in the rats modeled for 21 weeks(AUC=0.806, P=0.009) was superior to that for 4, 8, 12, and 16 weeks(AUC=0.520, 0.580, 0.741, 0.774, respectively), and STOM was meaningless in syndrome differentiation. In summary, the candidate marker gene for phlegm in SONFH is ELOVL6; the candidate marker genes for stasis are GYPA, RHAG, and ANK1; the candidate marker gene for deficiency is SLC2A1. The results help to reveal the biological connotations of phlegm, stasis, and deficiency in SONFH at the genetic level.

Tibetan medicine Ruyi Zhenbao Pill ameliorates neuropathic pain by inhibiting the CXCL10-CXCR3 pathway in spinal cord of spinal nerve ligation model.

ETHNOPHARMACOLOGICAL RELEVANCE: Ruyi Zhenbao Pill (RYZBP) is a traditional Tibetan medicine that has been used for over 300 years in China to treat neurological diseases, specifically neuropathic pain (NP). However, its characteristics and mechanism of action in treating NP remains unclear. AIM OF THE STUDY: Based on animal experiments and transcriptomics to evaluate the characteristics and mechanism of RYZBP in treating NP. METHODS: Mice were divided into six groups using random assignment: sham-operation group, spinal nerve ligation (SNL) group, RYZBP low (0.65 g kg-1), medium (1.30 g kg-1), high (2.60 g kg-1) doses groups, and positive drug pregabalin (PGB, 0.05 g kg-1) group. Mice received intragastrical administered for 14 consecutive days. SNL and intrathecal injection models were employed. The analgesic effects were assessed using the Von Frey test, Acetone test, and Hot Plate test. L5 spinal dorsal horns were collected for transcriptomics on day 15. The potential signaling pathways and Hub genes of RYZBP to ameliorate NP were obtained through transcriptomics and network pharmacology. Molecular docking was utilized to evaluate the binding ability of candidate active ingredients with the Hub genes. Finally, western blot (WB) and immunofluorescence (IF) were used to validate the predicted targets. RESULTS: RYZBP demonstrated a dose-dependent alleviation of mechanical allodynia, cold and heat stimulus-induced pain in SNL mice. Transcriptomics analysis identified 24 differentially expressed genes, and pathway enrichment analysis revealed that the CXCL10-CXCR3 signal axis may be the primary biological pathway through which RYZBP relieve NP. Molecular docking test indicated that the active ingredient in RYZBP exhibit a strong affinity for the target protein CXCL10. WB and IF tests showed that RYZBP can significantly inhibit CXCL10 and CXCR3 and its downstream molecules expression in the spinal dorsal horn of SNL mice. Additionally, intrathecal injection of rmCXCL10 worsened pain hypersensitivity, while RYZBP was able to suppress the pain hypersensitivity response induced by rmCXCL10 and reduce the expression levels of CXCL10 and CXCR3 and its downstream molecules. CONCLUSION: RYZBP had a significant analgesic effect on NP model, and this effect may be related to inhibiting the CXCL10-CXCR3 pathway in the spinal dorsal horn.

Porphyromonas gingivalis with collagen immunization induces ACPA-positive rheumatoid arthritis in C3H mice.

The pathogenic anti-citrullinated protein antibodies (ACPA) are thought to play a vital role in the initiation and immune maintenance of rheumatoid arthritis (RA). However, it is noteworthy that ACPA is not a salient characteristic of any conventional RA animal model. Porphyromonas gingivalis (Pg) is the first microorganism identified to induce citrullination and a target of autoantibodies in early rheumatoid arthritis (RA). Thus, we employed C3H mice with specific MHC types and combined Pg infection with collagen immunity to develop an animal model of ACPA-positive RA. The resulting model exhibited citrullination characteristics, as well as pathological and immune cell changes. 1) Mice showed a significant increase in ACPA levels, and various organs and tissues exhibited elevated levels of citrullinated protein. 2) The mice experienced heightened pain, inflammation, and bone destruction. 3) The spleen and lymph nodes of the mice showed a significant increase in the proportion of Tfh-GCB cell subpopulations responsible for regulating autoantibody production. In conclusion, the C3H mouse model of Pg infection with collagen immunity demonstrated significant alterations in ACPA levels, citrullinated protein expression, and immune cell subpopulations, which could be a crucial factor leading to increased pain, inflammation, and bone destruction.

[Characteristic changes of blood stasis syndrome in rat model of steroid-induced femoral head necrosis based on the combination of disease, syndrome, and symptom].

The approach combining disease, syndrome, and symptom was employed to investigate the characteristic changes of blood stasis syndrome in a rat model of steroid-induced osteonecrosis of the femoral head(SONFH) during disease onset and progression. Seventy-two male SD rats were randomized into a healthy control group and a model group. The rat model of SONFH was established by injection of lipopolysaccharide(LPS) in the tail vein at a dose of 20 µg·kg~(-1)·d~(-1) on days 1 and 2 and gluteal intramuscular injection of methylprednisolone sodium succinate(MPS) at a dose of 40 mg·kg~(-1)·d~(-1) on days 3-5, while the healthy control group received an equal volume of saline. The mechanical pain test, tongue color RGB technique, gait detection, open field test, and inclined plane test were employed to assess hip pain, tongue color, limping, joint activity, and lower limb strength, respectively, at different time points within 21 weeks of modeling. At weeks 2, 4, 8, 12, 16, and 21 after modeling, histopathological changes of the femoral head were observed by hematoxylin-eosin(HE) staining and micro-CT scanning; four coagulation items were measured by rotational thromboelastometry; and enzyme-linked immunosorbent assay(ELISA) was employed to determine the levels of six blood lipids, vascular endothelial growth factor(VEGF), endothelin-1(ET-1), nitric oxide(NO), tissue-type plasminogen activator(t-PA), plasminogen activator inhibitor factor-1(PAI-1), bone gla protein(BGP), alkaline phosphatase(ALP), receptor activator of nuclear factor-κB(RANKL), osteoprotegerin(OPG), and tartrate-resistant acid phosphatase 5b(TRAP5b) in the serum, as well as the levels of 6-keto-prostaglandin 1α(6-keto-PGF1α) and thromboxane B2(TXB2) in the plasma. The results demonstrated that the pathological alterations in the SONFH rats were severer over time. The bone trabecular area ratio, adipocyte number, empty lacuna rate, bone mineral density(BMD), bone volume/tissue volume(BV/TV), trabecular thickness(Tb.Th), trabecular number(Tb.N), bone surface area/bone volume(BS/BV), and trabecular separation(Tb.Sp) all significantly increased or decreased over the modeling time after week 4. Compared with the healthy control group, the mechanical pain threshold, gait swing speed, stride, standing time, and walking cycle of SONFH rats changed significantly within 21 weeks after modeling, with the greatest difference observed 12 weeks after modeling. The time spent in the central zone, rearing score, and maximum tilt angle in the open field test of SONFH rats also changed significantly over the modeling time. Compared with the healthy control group, the R, G, and B values of the tongue color of the model rats decreased significantly, with the greatest difference observed 11 weeks after modeling. The levels of total cholesterol(TC), total triglycerides(TG), low-density lipoprotein-cholesterol(LDL-C), and apoprotein B(ApoB) in the SONFH rats changed significantly 4 and 8 weeks after modeling. The levels of VEGF, ET-1, NO, t-PA, PAI-1, 6-keto-PGF1α, TXB2, four coagulation items, and TXB2/6-keto-PGF1α ratio in the serum of SONFH rats changed significantly 4-16 weeks after modeling, with the greatest differences observed 12 weeks after modeling. The levels of BGP, TRAP5b, RANKL, OPG, and RANKL/OPG ratio in the serum of SONFH rats changed significantly 8-21 weeks after modeling. During the entire onset and progression of SONFH in rats, the blood stasis syndrome characteristics such as hyperalgesia, tongue color darkening, gait abnormalities, platelet, vascular, and coagulation dysfunctions were observed, which gradually worsened and then gradually alleviated in the disease course(2-21 weeks), with the most notable differences occurred around 12 weeks after modeling.

Pien-Tze-Huang prevents hepatocellular carcinoma by inducing ferroptosis via inhibiting SLC7A11-GSH-GPX4 axis.

BACKGROUND: Malignant transformation from hepatic fibrosis to carcinogenesis may be a therapeutic target for hepatocellular carcinoma (HCC). The aim of this study was to evaluate anti-cancer efficacy of Pien-Tze-Huang (PZH), and to investigate the underlying mechanisms by integrating transcriptional regulatory network analysis and experimental validation. METHODS: A diethylnitrosamine (DEN)-induced HCC model in rats was established and used to evaluate the anti-cancer efficacy of PZH. After detecting a transcriptomic profiling, the "disease-related gene-drug effective target" interaction network was constructed, and the candidate targets of PZH against malignant transformation from hepatic fibrosis to HCC were identified and verified in vitro. RESULTS: PZH effectively alleviated the pathological changes of hepatic fibrosis and cirrhosis, and inhibited tumor formation and growth in DEN-induced HCC rats. Additionally, the administration of PZH reduced the levels of various hepatic function-related serological indicators significantly. Mechanically, a ferroptosis-related SLC7A11-GSH-GPX4 axis might be one of potential targets of PZH against malignant transformation from hepatic fibrosis to HCC. Especially, high SLC7A11 expression may be associated with poor prognosis of HCC patients. Experimentally, the administration of PZH markedly increased the trivalent iron and ferrous ion, suppressed the expression levels of SLC7A11 and GPX4 proteins, and reduced the GSH/GSSG ratio in the liver tissues of DEN-induced HCC rats. CONCLUSIONS: Our data offer an evidence that PZH may effectively improve the hepatic fibrosis microenvironment and prevent the occurrence of HCC through promoting ferroptosis in tumor cells via inhibiting the SLC7A11-GSH-GPX4 axis, implying that PZH may be a potential candidate drug for prevention and treatment of HCC at an early stage.

Parkin Maintains Robust Pacemaking in Human Induced Pluripotent Stem Cell-Derived A9 Dopaminergic Neurons.

BACKGROUND: The degeneration of nigral (A9) dopaminergic (DA) neurons results in cardinal motor symptoms that define Parkinson's disease (PD). Loss-of-function mutations in parkin are linked to a rare form of early-onset PD that is inherited recessively. OBJECTIVE: We generated isogenic human A9 DA neurons with or without parkin mutations to establish the causal relationship between parkin mutations and the dysfunction of human A9 DA neurons. METHODS: Using TALEN (transcription activator-like effector nuclease)- or CRISPR/Cas9-mediated gene targeting, we produced two isogenic pairs of naivetropic induced pluripotent stem cells (iPSCs) by repairing exon 3 deletions of parkin in iPSCs derived from a PD patient and by introducing the PD-linked A82E mutation into iPSCs from a healthy subject. The four lines of isogenic iPSCs were differentiated to A9 DA neurons, which fired spontaneous pacemaking action potentials (AP) dependent on L-type Ca2+ channels. RESULTS: The frequency of the pacemaking APs was significantly reduced by parkin mutations introduced to normal neurons. Consistent with this, isogenic repair of parkin mutations significantly increased the frequency from that observed in patient-derived neurons. CONCLUSIONS: The results show that parkin maintains robust pacemaking in human iPSC-derived A9 DA neurons. The function is critical to normal DA transmission required for controlling voluntary locomotor activities. © 2023 International Parkinson and Movement Disorder Society.

Tongluo Shenggu capsule promotes angiogenesis to ameliorate glucocorticoid-induced femoral head necrosis via upregulating VEGF signaling pathway.

BACKGROUND: Tongluo Shenggu Capsule (TLSGC) is a product of Traditional Chinese patent medicine that has been effective in glucocorticoid-induced osteonecrosis of the femoral head (GIONFH) clinically for many years. It is made from water extracts of a well-used herbal and dietary supplement-pigeon pea leaves. Nevertheless, the material basis and pharmacological mechanisms of TLSGC ameliorating GIONFH needed to be better defined. PURPOSE: To investigate the material basis and pharmacological mechanisms of TLSGC to ameliorate GIONFH. METHODS: The chemical compositions in TLSGC were characterized using the LC-MS system. Based on integrating the relevant targets of TLSGC in MedChem Studio software and GIONFH-related genes in our previous work, a "drug targets-disease genes" interaction network was constructed. The candidate targets of TLSGC ameliorating GIONFH were filtrated by topological characteristic parameters and further experimental validated based on methylprednisolone-induced rat model and dexamethasone-inhibited human umbilical vein endothelial cells (HUVECs). RESULTS: A total of 33 chemical compositions were characterized in TLSGC. Based on these compositions and GIONFH-related genes, 122 hub genes were selected according to topological parameters calculation. Biological functions were mainly enriched in four over-expressed modules of vascular damage, inflammation and apoptosis, bone metabolism and energy metabolism. The hub genes had the maximum enrichment degree in the VEGF-VEGFR2-PKC-Raf1-MEK-ERK signaling axis of the VEGF pathway. Experimentally, the therapeutic effects of TLSGC against GIONFH in rats were proved by micro-CT and pathological examination. Then, the protective effects of TLSGC on vascular damage were determined using angiography, CD31 immunohistochemistry, vascular function indicators in vivo, aortic ring test ex vivo, and the HUVECs activities in vitro including migration, invasion and tube formation. Mechanically, TLSGC effectively suppressed the downregulation of VEGF and VEGFR2 and their downstream targets, including Raf-1, PKC, p-MEK, and p-ERK proteins both in vivo and in vitro. CONCLUSION: TLSGC could promote angiogenesis by upregulating the VEGF-VEGFR2-PKC-Raf-1-MEK-ERK signaling axis, thereby exerting an apparent curative effect on GIONFH.

[Mechanism of Panlongqi Tablets intervening in vertebral artery type of cervical spondylosis in rats through PI3K/AKT signaling pathway based on network pharmacology and experimental verification].

This study aimed to further explore the relevant mechanism of action by network pharmacology integrated with animal experimental verification based on previous proven effective treatment of vertebral artery type of cervical spondylosis(CSA) by Panlongqi Tablets. Bionetwork analysis was performed to establish drug-disease interaction network, and it was found that the key candidate targets of Panlongqi Tablets were enriched in multiple signaling pathways related to CSA pathological links, among which phosphatidylinositol 3-kinase(PI3 K)/serine-threonine kinase(AKT/PKB) signaling pathway was the most significant. Further, mixed modeling method was used to build the CSA rat model, and the rats were divided into normal, model, Panlongqi Tablets low-, medium-and high-dose(0.16, 0.32, 0.64 g·kg~(-1)) and Jingfukang Granules(positive drug, 1.35 g·kg~(-1)) groups. After successful modeling, the rats were administered for 8 consecutive weeks. Pathological changes of rat cervical muscle tissues were detected by hematoxylin-eosin(HE) staining, and the content of interleukin-1ß(IL-1ß), tumor necrosis factor-α(TNF-α), vascular endothelial cell growth factor(VEGF) and chemokine(C-C motif) ligand 2(CCL2) in rat serum and/or cervical tissues was determined by enzyme-linked immunosorbent assay(ELISA). Western blot was employed to detect the protein expression levels of chemokine(C-C motif) receptor 2(CCR2), PI3 K, AKT, phosphorylated AKT(p-AKT), I-kappa-B-kinase beta(IKK-beta/IKKß), nuclear factor kappa B(NF-κB P65) and phosphorylated nuclear factor kappa B(NF-κB p-P65) in rat cervical tissues, and positive expression of p-NF-κB P65 in rat cervical muscle tissues was detected by immunofluorescence. The results showed that Panlongqi Tablets at different doses improved the degree of muscle fibrosis and inflammation in cervical muscle tissues of CSA rats, and reduced the content of inflammatory factors IL-1ß, TNF-α, VEGF, CCL2 and CCR2 in serum and/or cervical tissues. The protein expression levels of PI3 K, p-AKT, IKKß and p-NF-κB P65 as well as the nuclear entry of p-NF-κB P65 in cervical tissues were down-regulated. These findings suggest that Panlongqi Tablets can significantly inhibit the inflammatory response of CSA rats, and the mechanism of action may be related to the down-regulation of the activation of PI3 K/AKT signaling pathway.

[Effect of Jianpi Huogu Formula on function damage of vascular endothelial cells induced by glucocorticoid].

This study aimed to observe the intervention effect of Jianpi Huogu Formula(JPHGF) on the functional damage of vascular endothelial cells caused by glucocorticoid, and explore its action mechanism from the PI3 K/Akt and mitogen activated protein kinase(MAPK) signaling pathways. The extracted thoracic aorta ring of normal SD rats were intervened first with vascularendothelial growth factor(VEGF, 20 µg·L-1) and/or sodium succinate(MPS, 0. 04 g·L-1) in vitro and then with JPHGF(8, 16, and 32 µg·L-1) for five mcontinuous ethylpdays, rednisolofollowed nebythe statistics of the number, length, and area of microvessels budding fromvascular rings. In addition, the human umbilical vein endothelial cells(HUVECs) induced by VEGF(20 µg·L-1) were added with MPS(0. 04 g·L-1) and then with JPHGF(8, 16, and 32 µg·L-1) for observing the migration, invasion, and luminal formation abilities of HUVECs in the migration, invasion and luminal formation experiments. The protein expression levels of PI3 K, p-Akt, p-JN K, and p-ERK in HUVECs were assayed by Western blot. The results showed that JPHGF dose-dependently improved the num-ber,length, and area of microvessels in MPS-induced rat thoracic aortic ring, reversed the migration, invasion and lumen formation abiliti es of HUVECs reduced by MPS, and up-regulated the protein expression levels of PI3 K, p-Akt, and p-JNK in HUVECs. All thesehave suggested that JPHGF exerts the protective effect against hormone-induced damage to the angiogenesis of vascular endothelial cells by activating the PI3 K/Akt and MAPK signaling pathways, which has provided reference for exploring the mechanism of JPHGF in treating s teroid-induced avascular necrosis of femoral head(SANFH) and also the experimental evidence for enriching the scientific connotationof spleen-invigorating and blood-activating therapy.

Generation of mouse-human chimeric embryos.

Naive human pluripotent stem cells (hPSCs) can be used to generate mature human cells of all three germ layers in mouse-human chimeric embryos. Here, we describe a protocol for generating mouse-human chimeric embryos by injecting naive hPSCs converted from the primed state. Primed hPSCs are treated with a mammalian target of rapamycin inhibitor (Torin1) for 3 h and dissociated to single cells, which are plated on mouse embryonic fibroblasts in 2iLI medium, a condition essentially the same for culturing mouse embryonic stem cells. After 3-4 d, bright, dome-shaped colonies with mouse embryonic stem cell morphology are passaged in 2iLI medium. Established naive hPSCs are injected into mouse blastocysts, which produce E17.5 mouse embryos containing 0.1-4.0% human cells as quantified by next-generation sequencing of 18S ribosomal DNA amplicons. The protocol is suitable for studying the development of hPSCs in mouse embryos and may facilitate the generation of human cells, tissues and organs in animals.

Melanocortin Receptor 4 (MC4R) Signaling System in Nile Tilapia.

The melanocortin receptor 4 (MC4R) signaling system consists of MC4R, MC4R ligands [melanocyte-stimulating hormone (MSH), adrenocorticotropin (ACTH), agouti-related protein (AgRP)], and melanocortin-2 receptor accessory protein 2 (MRAP2), and it has been proposed to play important roles in feeding and growth in vertebrates. However, the expression and functionality of this system have not been fully characterized in teleosts. Here, we cloned tilapia MC4R, MRAP2b, AgRPs (AgRP, AgRP2), and POMCs (POMCa1, POMCb) genes and characterized the interaction of tilapia MC4R with MRAP2b, AgRP, α-MSH, and ACTH in vitro. The results indicate the following. (1) Tilapia MC4R, MRAP2b, AgRPs, and POMCs share high amino acid identity with their mammalian counterparts. (2) Tilapia MRAP2b could interact with MC4R expressed in CHO cells, as demonstrated by Co-IP assay, and thus decrease MC4R constitutive activity and enhance its sensitivity to ACTH1-40. (3) As in mammals, AgRP can function as an inverse agonist and antagonist of MC4R, either in the presence or absence of MRAP2b. These data, together with the co-expression of MC4R, MRAP2b, AgRPs, and POMCs in tilapia hypothalamus, suggest that as in mammals, ACTH/α-MSH, AgRP, and MRAP2 can interact with MC4R to control energy balance and thus play conserved roles in the feeding and growth of teleosts.

TET1 Deficiency Impairs Morphogen-free Differentiation of Human Embryonic Stem Cells to Neuroectoderm.

The TET family of 5-methylcytosine (5mC) dioxygenases plays critical roles in development by modifying DNA methylation. Using CRISPR, we inactivated the TET1 gene in H9 human embryonic stem cells (hESCs). Mutant H9 hESCs remained pluripotent, even though the level of hydroxymethylcytosine (5hmC) decreased to 30% of that in wild-type cells. Neural differentiation induced by dual SMAD inhibitors was not significantly affected by loss of TET1 activity. However, in a morphogen-free condition, TET1 deficiency significantly reduced the generation of NESTIN+SOX1+ neuroectoderm cells from 70% in wild-type cells to 20% in mutant cells. This was accompanied by a 20-fold reduction in the expression level of PAX6 and a significant decrease in the amount of 5hmC on the PAX6 promoter. Overexpression of the TET1 catalytic domain in TET1-deficient hESCs significantly increased 5hmC levels and elevated PAX6 expression during differentiation. Consistent with these in vitro data, PAX6 expression was significantly decreased in teratomas formed by TET1-deficient hESCs. However, TET1 deficiency did not prevent the formation of neural tube-like structures in teratomas. Our results suggest that TET1 deficiency impairs the intrinsic ability of hESCs to differentiate to neuroectoderm, presumably by decreasing the expression of PAX6, a key regulator in the development of human neuroectoderm.

Transient inhibition of mTOR in human pluripotent stem cells enables robust formation of mouse-human chimeric embryos.

It has not been possible to generate naïve human pluripotent stem cells (hPSCs) that substantially contribute to mouse embryos. We found that a brief inhibition of mTOR with Torin1 converted hPSCs from primed to naïve pluripotency. The naïve hPSCs were maintained in the same condition as mouse embryonic stem cells and exhibited high clonogenicity, rapid proliferation, mitochondrial respiration, X chromosome reactivation, DNA hypomethylation, and transcriptomes sharing similarities to those of human blastocysts. When transferred to mouse blastocysts, naïve hPSCs generated 0.1 to 4% human cells, of all three germ layers, including large amounts of enucleated red blood cells, suggesting a marked acceleration of hPSC development in mouse embryos. Torin1 induced nuclear translocation of TFE3; TFE3 with mutated nuclear localization signal blocked the primed-to-naïve conversion. The generation of chimera-competent naïve hPSCs unifies some common features of naïve pluripotency in mammals and may enable applications such as human organ generation in animals.

Early astragaloside IV administration attenuates experimental autoimmune encephalomyelitis in mice by suppressing the maturation and function of dendritic cells.

AIMS: Dendritic cells (DCs) actively participate in the pathogenesis of multiple sclerosis (MS), an autoimmune disease. Astragaloside IV (ASI), an active monomer isolated from the Chinese medicine Astragalus membranaceus, has a wide range of pharmacological effects. We aimed to elucidate the effects of ASI on the development of DCs in the early stage of MS/EAE. MAIN METHODS: The mice were administered with ASI (20 mg/kg) daily 3 days in advance of EAE induction and continuously until day 7 post-immunization. The effect of ASI on CD11c+ DC cells from bone marrow (BMDCs) or the spleen of EAE mice at day 7 post-immunization were investigated respectively by flow cytometry, ELISA, western blot, real-time PCR and immunofluorescence. KEY FINDINGS: ASI administration in the early stage of EAE was demonstrated to delay the onset and alleviate the severity of the disease. ASI inhibited the maturation and the antigen presentation of DCs in spleen of EAE mice and LPS-stimulated BMDCs, as evidenced by decreased expressions of CD11c, CD86, CD40 and MHC II. Accordingly, DCs treated by ASI secreted less IL-6 and IL-12, and prevented the differentiation of CD4+ T cells into Th1 and Th17 cells, which was probably through inhibiting the activation of NFκB and MAPKs signaling pathways. SIGNIFICANCE: Our results implicated the alleviative effect of early ASI administration on EAE might be mediated by suppressing the maturation and function of DCs. The novel findings may add to our knowledge of ASI in the potentially clinical treatment of MS.

Stability and Hopf Bifurcation of a Vector-Borne Disease Model with Saturated Infection Rate and Reinfection.

This paper established a delayed vector-borne disease model with saturated infection rate and cure rate. First of all, according to the basic reproductive number R 0, we determined the disease-free equilibrium E 0 and the endemic equilibrium E 1. Through the analysis of the characteristic equation, we consider the stability of two equilibriums. Furthermore, the effect on the stability of the endemic equilibrium E 1 by delay was studied, the existence of Hopf bifurcations of this system in E 1 was analyzed, and the length of delay to preserve stability was estimated. The direction and stability of the Hopf bifurcation were also been determined. Finally, we performed some numerical simulation to illustrate our main results.

Dopamine Induces Oscillatory Activities in Human Midbrain Neurons with Parkin Mutations.

Locomotor symptoms in Parkinson's disease (PD) are accompanied by widespread oscillatory neuronal activities in basal ganglia. Here, we show that activation of dopamine D1-class receptors elicits a large rhythmic bursting of spontaneous excitatory postsynaptic currents (sEPSCs) in midbrain neurons differentiated from induced pluripotent stem cells (iPSCs) of PD patients with parkin mutations, but not normal subjects. Overexpression of wild-type parkin, but not its PD-causing mutant, abolishes the oscillatory activities in patient neurons. Dopamine induces a delayed enhancement in the amplitude of spontaneous, but not miniature, EPSCs, thus increasing quantal content. The results suggest that presynaptic regulation of glutamatergic transmission by dopamine D1-class receptors is significantly potentiated by parkin mutations. The aberrant dopaminergic regulation of presynaptic glutamatergic transmission in patient-specific iPSC-derived midbrain neurons provides a mechanistic clue to PD pathophysiology, and it demonstrates the usefulness of this model system in understanding how mutations of parkin cause movement symptoms in Parkinson's disease.

Protocatechuic aldehyde inhibits TNF-α-induced fibronectin expression in human umbilical vein endothelial cells via a c-Jun N-terminal kinase dependent pathway.

Fibronectin (FN) is one of the most important extracellular matrix proteins and plays an important role in the pathogenesis of atherosclerosis (AS). The aim of the present study was to evaluate the effect of a potent, water-soluble antioxidant, protocatechuic aldehyde (PA), which is derived from the Chinese herb Salvia miltiorrhiza, on the expression of FN in human umbilical vein endothelial cells (HUVECs) stimulated with tumor necrosis factor-α (TNF-α). The pharmacological effects of PA on the production of FN were investigated using ELISA and western blot analysis. In addition, ELISA and western blot analysis were used to examine the activation and suppression of the mitogen-activated protein kinase (MAPK) pathways and nuclear factor (NF)-κB in TNF-α-stimulated HUVECs, in order to explore the underlying pharmacological mechanism of PA. The inhibitory effect of PA on the total generation of reactive oxygen species (ROS) in TNF-α-stimulated HUVECs was assessed using 2',7'-dichlorofluorescein diacetate. Pretreatment of HUVECs with PA (0.15, 0.45 and 1.35 mM) for 18 h markedly attenuated the TNF-α-stimulated FN surface expression and secretion in a dose-dependent manner. Intracellular ROS generation and the expression of extracellular signal-regulated kinase 1 and 2 (ERK1/2), c-Jun N-terminal kinase (JNK) and p38 MAPK (p38) were significantly induced by TNF-α (2 ng/ml) in HUVECs. TNF-α-induced ROS generation and JNK activation were inhibited by PA in a concentration-dependent manner. By contrast, ERK1/2 and p38 activation was not significantly affected by PA. Pretreatment of HUVECs with PA for 18 h markedly attenuated TNF-α-stimulated NF-κB activation. In conclusion, the present findings suggest that PA inhibits TNF-α-induced FN expression in HUVECs through a mechanism that involves ROS/JNK and NF-κB.

Generation of Naivetropic Induced Pluripotent Stem Cells from Parkinson's Disease Patients for High-Efficiency Genetic Manipulation and Disease Modeling.

The lack of robust Parkinson's disease (PD) phenotype in parkin knockout rodents and the identification of defective dopaminergic (DA) neurotransmission in midbrain DA neurons derived from induced pluripotent stem cells (iPSC) of PD patients with parkin mutations demonstrate the utility of patient-specific iPSCs as an effective system to model the unique vulnerabilities of midbrain DA neurons in PD. Significant efforts have been directed at developing efficient genomic engineering technologies in human iPSCs to study diseases such as PD. In the present study, we converted patient-specific iPSCs from the primed state to a naivetropic state by DOX-induced expression of transgenes (Oct4, Sox2, Klf4, c-Myc, and Nanog) and the use of 2iL (MEK inhibitor PD0325901, GSK3 inhibitor CHIR99021, and human LIF). These patient-specific naivetropic iPSCs were pluripotent in terms of marker expression, spontaneous differentiation in vitro, and teratoma formation in vivo. They exhibited morphological, proliferative, and clonogenic characteristics very similar to naive mouse embryonic stem cells (ESC). The high clonal efficiency and proliferation rate of naivetropic iPSCs enabled very efficient gene targeting of GFP to the PITX3 locus by transcription activator-like effector nuclease. The naivetropic iPSCs could be readily reverted to the primed state upon the withdrawal of DOX, 2iL, and the switch to primed-state hESC culture conditions. Midbrain DA neurons differentiated from the reverted iPSCs retained the original phenotypes caused by parkin mutations, attesting to the robustness of these phenotypes and the usefulness of genomic engineering in patient-specific naivetropic iPSCs for studying PD.

Parkin mutations reduce the complexity of neuronal processes in iPSC-derived human neurons.

Parkinson's disease (PD) is characterized by the degeneration of nigral dopaminergic (DA) neurons and non-DA neurons in many parts of the brain. Mutations of parkin, an E3 ubiquitin ligase that strongly binds to microtubules, are the most frequent cause of recessively inherited PD. The lack of robust PD phenotype in parkin knockout mice suggests a unique vulnerability of human neurons to parkin mutations. Here, we show that the complexity of neuronal processes as measured by total neurite length, number of terminals, number of branch points, and Sholl analysis was greatly reduced in induced pluripotent stem cell (iPSC)-derived TH(+) or TH(-) neurons from PD patients with parkin mutations. Consistent with these, microtubule stability was significantly decreased by parkin mutations in iPSC-derived neurons. Overexpression of parkin, but not its PD-linked mutant nor green fluorescent protein, restored the complexity of neuronal processes and the stability of microtubules. Consistent with these, the microtubule-depolymerizing agent colchicine mimicked the effect of parkin mutations by decreasing neurite length and complexity in control neurons while the microtubule-stabilizing drug taxol mimicked the effect of parkin overexpression by enhancing the morphology of parkin-deficient neurons. The results suggest that parkin maintains the morphological complexity of human neurons by stabilizing microtubules.

Nucleolar molecular signature of pluripotent stem cells.

Induced pluripotent stem cells (iPSC) are generated by reprogramming somatic cells to the pluripotent state. Identification and quantitative characterization of changes in the molecular organization of the cell during the process of cellular reprogramming is valuable for stem cell research and advancement of its therapeutic applications. Here we employ quantitative Raman microspectroscopy and biomolecular component analysis (BCA) for a comparative analysis of the molecular composition of nucleoli in skin fibroblasts and iPSC derived from them. We report that the cultured fibroblasts obtained from different human subjects, share comparable concentrations of proteins, RNA, DNA, and lipids in the molecular composition of nucleoli. The nucleolar molecular environment is drastically changed in the corresponding iPSC. We measured that the transition from skin fibroblasts to iPSC is accompanied by a statistically significant increase in protein concentrations ~1.3-fold, RNA concentrations ~1.3-fold, and DNA concentrations ~1.4-fold, while no statistically significant difference was found for the lipid concentrations. The analysis of molecular vibrations associated with diverse aminoacids and protein conformations indicates that nucleoli of skin fibroblasts contain similar subsets of proteins, with prevalence of tyrosine. In iPSC, we observed a higher signal from tryptophan with an increase in the random coil and α helix protein conformations, indicating changes in the subset of nucleolar proteins during cell reprogramming. At the same time, the concentrations of major types of macromolecules and protein conformations in the nucleoli of iPSC and human embryonic stem cells (hESC) were found to be similar. We discuss these results in the context of nucleolar function and conclude that the nucleolar molecular content is correlated with the cellular differentiation status. The approach described here shows the potential for spectroscopically monitoring changes in macromolecular organization of the cell at different stages of reprogramming.