APP in the Neuromuscular Junction for the Development of Sarcopenia and Alzheimer's Disease.

Sarcopenia, an illness condition usually characterized by a loss of skeletal muscle mass and muscle strength or function, is often associated with neurodegenerative diseases, such as Alzheimer's disease (AD), a common type of dementia, leading to memory loss and other cognitive impairment. However, the underlying mechanisms for their associations and relationships are less well understood. The App, a Mendelian gene for early-onset AD, encodes amyloid precursor protein (APP), a transmembrane protein enriched at both the neuromuscular junction (NMJ) and synapses in the central nervous system (CNS). Here, in this review, we highlight APP and its family members' physiological functions and Swedish mutant APP (APPswe)'s pathological roles in muscles and NMJ. Understanding APP's pathophysiological functions in muscles and NMJ is likely to uncover insights not only into neuromuscular diseases but also AD. We summarize key findings from the burgeoning literature, which may open new avenues to investigate the link between muscle cells and brain cells in the development and progression of AD and sarcopenia.

The laterodorsal tegmentum-ventral tegmental area circuit controls depression-like behaviors by activating ErbB4 in DA neurons.

Dopamine (DA) neurons in the ventral tegmental area (VTA) are critical to coping with stress. However, molecular mechanisms regulating their activity and stress-induced depression were not well understood. We found that the receptor tyrosine kinase ErbB4 in VTA was activated in stress-susceptible mice. Deleting ErbB4 in VTA or in DA neurons, or chemical genetic inhibition of ErbB4 kinase activity in VTA suppressed the development of chronic social defeat stress (CSDS)-induced depression-like behaviors. ErbB4 activation required the expression of NRG1 in the laterodorsal tegmentum (LDTg); LDTg-specific deletion of NRG1 inhibited depression-like behaviors. NRG1 and ErbB4 suppressed potassium currents of VTA DA neurons and increased their firing activity. Finally, we showed that acute inhibition of ErbB4 after stress attenuated DA neuron hyperactivity and expression of depression-like behaviors. Together, these observations demonstrate a critical role of NRG1-ErbB4 signaling in regulating depression-like behaviors and identify an unexpected mechanism by which the LDTg-VTA circuit regulates the activity of DA neurons.

A novel spinal neuron connection for heat sensation.

Heat perception enables acute avoidance responses to prevent tissue damage and maintain body thermal homeostasis. Unlike other modalities, how heat signals are processed in the spinal cord remains unclear. By single-cell gene profiling, we identified ErbB4, a transmembrane tyrosine kinase, as a novel marker of heat-sensitive spinal neurons in mice. Ablating spinal ErbB4+ neurons attenuates heat sensation. These neurons receive monosynaptic inputs from TRPV1+ nociceptors and form excitatory synapses onto target neurons. Activation of ErbB4+ neurons enhances the heat response, while inhibition reduces the heat response. We showed that heat sensation is regulated by NRG1, an activator of ErbB4, and it involves dynamic activity of the tyrosine kinase that promotes glutamatergic transmission. Evidence indicates that the NRG1-ErbB4 signaling is also engaged in hypersensitivity of pathological pain. Together, these results identify a spinal neuron connection consisting of ErbB4+ neurons for heat sensation and reveal a regulatory mechanism by the NRG1-ErbB4 signaling.

Cranial irradiation impairs intrinsic excitability and synaptic plasticity of hippocampal CA1 pyramidal neurons with implications for cognitive function.

Radiation therapy is a standard treatment for head and neck tumors. However, patients often exhibit cognitive impairments following radiation therapy. Previous studies have revealed that hippocampal dysfunction, specifically abnormal hippocampal neurogenesis or neuroinflammation, plays a key role in radiation-induced cognitive impairment. However, the long-term effects of radiation with respect to the electrophysiological adaptation of hippocampal neurons remain poorly characterized. We found that mice exhibited cognitive impairment 3 months after undergoing 10 minutes of cranial irradiation at a dose rate of 3 Gy/min. Furthermore, we observed a remarkable reduction in spike firing and excitatory synaptic input, as well as greatly enhanced inhibitory inputs, in hippocampal CA1 pyramidal neurons. Corresponding to the electrophysiological adaptation, we found reduced expression of synaptic plasticity marker VGLUT1 and increased expression of VGAT. Furthermore, in irradiated mice, long-term potentiation in the hippocampus was weakened and GluR1 expression was inhibited. These findings suggest that radiation can impair intrinsic excitability and synaptic plasticity in hippocampal CA1 pyramidal neurons.

Health benefits of spices in individuals with chemotherapeutic drug-induced cardiotoxicity.

Cardio-oncology is an emerging field that mainly focuses on a series of cardiovascular diseases caused by chemotherapy and radiotherapy. In the history and culture of human nutrition, spices have been emphasized for their wide range of economic and medical applications in addition to being used as a food-flavoring agent and food preservative. Currently, an increasing number of studies have focused on the health benefits of spices in preventing cardiovascular diseases, particularly their antioxidant effects against cardiovascular damage. This review summarizes the cardioprotective effects of black pepper, cardamom, clove, garlic, ginger, onion, and other spices against chemotherapeutic drug-induced cardiotoxicity and the potential mechanisms. Here, we recommend dietary adjustments with spices for patients with cancer to prevent or mitigate the cardiotoxicity induced by chemotherapeutic agents.

Network Pharmacology Analysis of the Therapeutic Mechanisms Underlying Beimu-Gualou Formula Activity against Bronchiectasis with In Silico Molecular Docking Validation.

BACKGROUND: The classical Chinese herbal prescription Beimu-Gualou formula (BMGLF) has been diffusely applied to the treatment of respiratory diseases, including bronchiectasis. Although concerning bronchiectasis the effects and mechanisms of action of the BMGLF constituents have been partially elucidated, it remains to be determined how the formula in its entirety exerts therapeutic effects. METHODS: In this study, the multitarget mechanisms of BMGLF against bronchiectasis were predicted with network pharmacology analysis. Using prepared data, a drug-target interaction network was established and subsequently the core therapeutic targets of BMGLF were identified. Furthermore, the biological function and pathway enrichment of potential targets were analyzed to evaluate the therapeutic effects and pivotal signaling pathways of BMGLF. Finally, virtual molecular docking was performed to assess the affinities of compounds for the candidate targets. RESULTS: The therapeutic action of BMGLF against bronchiectasis involves 18 core target proteins, including the aforementioned candidates (i.e., ALB, ICAM1, IL10, and MAPK1), which are assumed to be related to biological processes such as drug response, cellular response to lipopolysaccharide, immune response, and positive regulation of NF-κB activity in bronchiectasis. Among the top 20 signaling pathways identified, mechanisms of action appear to be primarily related to Chagas disease, allograft rejection, hepatitis B, and inflammatory bowel disease. CONCLUSION: In summary, using a network pharmacology approach, we initially predicted the complex regulatory profile of BMGLF against bronchiectasis in which multilink suppression of immune/inflammatory responses plays an essential role. These results may provide a basis for novel pharmacotherapeutic approaches for bronchiectasis.

A discrete serotonergic circuit regulates vulnerability to social stress.

Exposure to social stress and dysregulated serotonergic neurotransmission have both been implicated in the etiology of psychiatric disorders. However, the serotonergic circuit involved in stress vulnerability is still unknown. Here, we explored whether a serotonergic input from the dorsal raphe (DR) to ventral tegmental area (VTA) influences vulnerability to social stress. We identified a distinct, anatomically and functionally defined serotonergic subpopulation in the DR that projects to the VTA (5-HTDR→VTA neurons). Moreover, we found that susceptibility to social stress decreased the firing activity of 5-HTDR→VTA neurons. Importantly, the bidirectional manipulation of 5-HTDR→VTA neurons could modulate susceptibility to social stress. Our findings reveal that the activity of 5-HTDR→VTA neurons may be an essential factor in determining individual levels of susceptibility to social stress and suggest that targeting specific serotonergic circuits may aid the development of therapies for the treatment of stress-related disorders.

The gut microbiota regulates autism-like behavior by mediating vitamin B6 homeostasis in EphB6-deficient mice.

BACKGROUND: Autism spectrum disorder (ASD) is a developmental disorder, and the effective pharmacological treatments for the core autistic symptoms are currently limited. Increasing evidence, particularly that from clinical studies on ASD patients, suggests a functional link between the gut microbiota and the development of ASD. However, the mechanisms linking the gut microbiota with brain dysfunctions (gut-brain axis) in ASD have not yet been full elucidated. Due to its genetic mutations and downregulated expression in patients with ASD, EPHB6, which also plays important roles in gut homeostasis, is generally considered a candidate gene for ASD. Nonetheless, the role and mechanism of EPHB6 in regulating the gut microbiota and the development of ASD are unclear. RESULTS: Here, we found that the deletion of EphB6 induced autism-like behavior and disturbed the gut microbiota in mice. More importantly, transplantation of the fecal microbiota from EphB6-deficient mice resulted in autism-like behavior in antibiotic-treated C57BL/6J mice, and transplantation of the fecal microbiota from wild-type mice ameliorated the autism-like behavior in EphB6-deficient mice. At the metabolic level, the disturbed gut microbiota in EphB6-deficient mice led to vitamin B6 and dopamine defects. At the cellular level, the excitation/inhibition (E/I) balance in the medial prefrontal cortex was regulated by gut microbiota-mediated vitamin B6 in EphB6-deficient mice. CONCLUSIONS: Our study uncovers a key role for the gut microbiota in the regulation of autism-like social behavior by vitamin B6, dopamine, and the E/I balance in EphB6-deficient mice, and these findings suggest new strategies for understanding and treating ASD. Video abstract.

A rapid and sensitive UHPLC-MS/MS method for the determination of ziyuglycoside I and its application in a preliminary pharmacokinetic study in healthy and leukopenic rats.

Ziyuglycoside I (ZgI), one of the main active ingredients in the popular Diyushengbai tablet made from Sanguisorba officinalis L., has been proven to relieve leukopenia clinically. However, to our knowledge, no studies have investigated the pharmacokinetics of either Diyushengbai tablet or ZgI in leukopenic vs. healthy individuals. In the present study, a rapid and sensitive UHPLC-MS/MS method was developed for detecting ZgI. On using this method on a novel cyclophosphamide-induced leukopenia model, we investigated differences in the pharmacokinetic characteristics of ZgI between leukopenic and normal rats. Chromatographic separation of ZgI and glycyrrhetinic acid (IS) was achieved via gradient elution in 0.5 min, and the total run time lasted for 5 min. Methodological validation results presented a good accuracy (102.6 %-110.8 %) and precision (% RSD ≤ 13.8) with a limit of quantitation of 0.5 ng/mL. Pharmacokinetic results showed a significantly shortened peak time (Tmax) (0.93 vs. 0.33 h) while a remarkably decreased maximum concentration (Cmax) (7.96 vs. 3.40 ng/L) in the 20 mg/kg leukopenia group in comparison with those in the 20 mg/kg normal group. In addition, a prolonged elimination half-life (t1/2ß) was observed in the 20 mg/kg leukopenia group (5.02 vs. 18.51 h). We observed similar trends in the 5 mg/kg oral dosing treatment and control groups, except for Cmax, which did not differ between the groups. We did not find pharmacokinetic differences in ZgI between the two leukopenia groups. Thus, the pharmacokinetic parameters of ZgI (e.g., Tmax, Cmax, and T1/2ß) changed based on the presence of a leukopenic state. This study may provide guidance for the development of ZgI as an agent for the treatment of leukopenia.

Plasmonic optical trapping of nanoparticles with precise angular selectivity.

In this paper, a plasmonic trapping scheme including a polystyrene nanoparticle with gold cap and a metal tip tweezers was proposed. We numerically investigated the optical trapping behavior of the metal tip to this asymmetric particle. The results show that the metal tip can capture the particle at the position of the gold cap due to the strong plasmonic interaction, while other positions of the particle cannot be captured by metal tip. Furthermore, the trapping angle of the nanoparticle can be adjusted by changing the incident wavelength. Precisely controlling the trapping angle of the nanoparticles in our study has important potential applications of optical tweezers, such as in single molecule manipulation.

ErbB4 Receptors in the Medial Habenula Regulate Contextual Fear Memory.

The Medial Habenular (MHb) and the Lateral Habenular nuclei are 2 main parts of the habenular complex (Hb). Recent studies showed that MHb plays an important role in memory, and in the expression of ErbB4. However, the expression of MHb ErbB4 receptor and its role in fear memory is not well understood. In this study, western blotting and quantitative real-time polymerase chain reaction were used to assess the protein and mRNA levels of ErbB4 in the process of contextual fear conditioning. A pharmacological approach was used to block and stimulate the ErbB4 receptor. Contextual fear conditioning tests induced a significant increase on the expression of ErbB4 at various times in the Hb and the MHb. Moreover, the blockade and stimulation of MHb ErbB4 receptors did not affect the fear formation but impaired and improved the contextual-dependent fear expression. Furthermore, in vitro electrophysiological recordings showed that the blockade of the MHb ErbB4 receptor reduced the presynaptic gamma-amino butyric acid release. ErbB4 is a susceptible gene for schizophrenia and the above findings may provide new insights into the mechanisms of fear-related responses.

17ß-Estradiol Inhibits PCSK9-Mediated LDLR Degradation Through GPER/PLC Activation in HepG2 Cells.

Plasma levels of PCSK9 are significantly higher in postmenopausal women. Pharmacologically increased estrogen levels have been shown to lower PCSK9 and LDL-C levels in animals and humans. The action of estrogen suggests that it has the ability to prevent PCSK9-mediated LDLR degradation in liver cells. However, little is known about how estrogen alters PCSK9-mediated LDLR degradation. Here, we report that 17ß-estradiol (ßE2) reduces PCSK9-mediated LDLR degradation by a mechanism that involves activation of the G protein-coupled estrogen receptor (GPER). In cultured HepG2 cells, ßE2 prevented the internalization of PCSK9, which subsequently lead to PCSK9-mediated LDLR degradation. The altered LDLR levels also resulted in an increase in LDL uptake that was not observed in the absence of PCSK9. In addition, we showed that clathrin was rapidly increased in the presence of PCSK9, and this increase was blocked by ßE2 incubation, suggesting rapid recruitment of clathrin in HepG2 cells. PLCγ activation and intracellular Ca2+ release were both increased due to the rapid effect of estrogen. By using a GPER antagonist G15, we demonstrated that the GPER mediates the action of estrogen. Together, the data from this in vitro study demonstrate that estrogen can regulate LDLR levels mainly through GPER activation, which prevents PCSK9-dependent LDLR degradation in HepG2 cells.

Dorsomedial prefrontal cortex 5-HT6 receptors regulate anxiety-like behavior.

The dorsomedial prefrontal cortex (dmPFC) plays a very important role in decision-related and anxiety-related information processing. It has enriched 5-HT6 receptors; however, the precise role of dmPFC 5-HT6 receptors in anxiety remains to be fully investigated. In this study, we injected dmPFC with the 5-HT6 receptor agonist EMD 386088 and antagonist SB 271046 using stereotactic technology. 5-HT6 receptor activation in mice increased time spent in the center area on the open-field test, increased exploration of the open arms on the elevated plus maze test, and increased ratio on the social interaction test. 5-HT6 receptor inactivation induced the opposite effects. In brain slices, EMD 386088 decreased both spontaneous inhibitory postsynaptic currents (sIPSC) and spontaneous excitatory postsynaptic currents (sEPSC), while SB 271046 only increased sEPSC. These effects of EMD 386088 and SB 271046 could be reversed by the GABAA receptor antagonist bicuculline (BMI) and positive allosteric modulator clonazepam (CLZ), respectively. Our results suggest that neurotransmission in the dmPFC by 5-HT6 receptor activation and inhibition may play an important role in anxiety-like behavior, and may provide new insight into the pathological mechanism and potential target of anxiety disorders.

[Analysis of difficult problems on European Union laws and regulations of traditional herbal medicinal products].

Registration of Chinese patent medicine in European Union (EU) is of great significance to the internationalization of traditional Chinese medicine as EU market acts as an important position in the global botanical market. In retrospect, the domestic studies on EU regulations of traditional herbal medicinal products have been conducted for more than 10 years, but there is still some cognitive bias and lack of research. In this paper, a review of the relevant research progress and the main misunderstanding problems about Directive 2004/24/EC, like the centralized and decentralized supervision system of traditional herbal medicinal products in the EU, marketing authorization procedures for traditional herbal medicinal products, Community Herbal Monograph and List Entries, would be systematically analyzed, so as to provide reference for the registration of Chinese patent medicine in EU.

Xinxuekang Regulates Reverse Cholesterol Transport by Improving High-density Lipoprotein Synthesis, Maturation, and Catabolism.

Di'ao Xinxuekang (XXK) is an herbal product in China and the Netherlands that has been clinically shown to attenuate atherosclerosis; however, the underlying antiatherosclerotic mechanism remains unclear. Because of its role in cholesterol homeostasis, reverse cholesterol transport (RCT) is a potential target for these beneficial effects. This study investigated the effects of XXK on RCT and related proteins. After treating ApoE-deficient mice with XXK for 8 weeks, we observed an increase in the expression level of ATP-binding cassette transporter A1 and ATP-binding cassette transporter G1, which in turn stimulated cholesterol efflux and reduced aortic atherosclerotic lesion area. XXK also increased high-density lipoprotein (HDL) synthesis by modulating the peroxisome proliferator-activated receptor γ/liver X receptor α/ATP-binding cassette transporter A1 pathway and promoted HDL maturity by increasing serum lecithin-cholesterol acyltransferase. In addition, XXK improved the selective uptake of HDL-cholesteryl ester by increasing the expression of scavenger receptor class B type I. This is the first study to show that XXK confers a regulation of RCT, at least in part, by improving HDL synthesis, maturation, and catabolism.

Satb2 Ablation Impairs Hippocampus-Based Long-Term Spatial Memory and Short-Term Working Memory and Immediate Early Genes (IEGs)-Mediated Hippocampal Synaptic Plasticity.

Special AT-rich sequence-binding protein 2 (Satb2) is a protein binding to the matrix attachment regions of DNA and important for gene regulation. Patients with SATB2 mutation usually suffer moderate to severe mental retardation. However, the mechanisms for the defects of intellectual activities in patients with SATB2 mutation are largely unclear. Here we established the heterozygous Satb2 mutant mice and Satb2 conditional knockout mice to mimic the patients with SATB2 mutation and figured out the role of Satb2 in mental activities. We found that the spatial memory and working memory were significantly damaged in the heterozygous Satb2 mutant mice, early postnatal Satb2-deficient mice (CaMKIIα-Cre+Satb2fl/fl mice), and adult Satb2 ablation mice (Satb2fl/fl mice injected with CaMKIIα-Cre virus). Functionally, late phase long-term potentiation (L-LTP) in these Satb2 mutant mice was greatly impaired. Morphologically, in CA1 neurons of CaMKIIα-Cre+Satb2fl/fl mice, we found decreased spine density of the basal dendrites and less branches of apical dendrites that extended into lacunar molecular layer. Mechanistically, expression levels of immediate early genes (IEGs) including Fos, FosB, and Egr1 were significantly decreased after Satb2 deletion. And, Satb2 could regulate expression of FosB by binding to the promoter of FosB directly. In general, our study uncovers that Satb2 plays an important role in spatial memory and working memory by regulating IEGs-mediated hippocampal synaptic plasticity.

Neuregulin 1-ErbB4 signaling in the bed nucleus of the stria terminalis regulates anxiety-like behavior.

The bed nucleus of the stria terminalis (BNST), a nucleus defined as part of the extended amygdala, is involved in the expression of anxiety disorders. However, the regulatory mechanisms of BNST inhibitory activity that is involved in anxiety are unknown. Here, we showed that blocking neuregulin 1 (NRG1)-ErbB4 signaling in the BNST of mice, by either neutralizing endogenous NRG1 with ecto-Erbb4 or antagonizing the ErbB4 receptor with its specific inhibitor, produced anxiogenic responses. Interestingly, application of exogenous NRG1 into the BNST induced no anxiolytic effects, suggesting saturating activity of endogenous NRG1. While infusion of the GABAA receptor antagonist bicuculline into the BNST also led to anxiety-related behaviors, it did not worsen the anxiogenic effects produced by blocking NRG1-ErbB4 signaling, suggesting possible involvement of GABAergic neurotransmission. Further, in vitro electrophysiological recordings showed that BNST NRG1-ErbB4 signaling regulated the presynaptic GABA release. Together, these results suggest that NRG1-ErbB4 signaling in the BNST may play an important role in regulating anxiety-like behaviors.

[SCHWABE Company's patent portfolio of Ginkgo biloba preparation].

SCHWABE Company in German is the first and largest manufacturer of Ginkgo biloba preparation. The company not only has leading technology in this field, but also protects its own market effectively through the high quality of patent drafting and exactly patent layout. Based on multi-angle analysis for patent portfolio of G. biloba preparation at application time, legal status, globally layout, Chinese layout, the article provides technical reference of research and development of G. biloba, also provides valuable experience of traditonal Chinese medicine patent portfolio layout for Chinese enterprises.

[Effect of total saponins from Sanguisorba officinalis on megakaryocyte progenitor cells proliferation, differentiation and relative receptor expression].

OBJECTIVE: To investigate the effects of total saponins from Sanguisorba officinalis (DYS) on hematopoietic cell proliferation, differentiation and the expression level of IL-3R and c-kit. METHOD: Baf3 and 32D cells were cultured with or without IL-3, then the cells were exposed to DYS in different concentrations of 5, 10, 20, 30 and 40 mg x L(-1) for 24, 48, 72 and 96 hours separately. After that, the cell proliferation and differentiation capacity were determinated by the methods of CCK8 and Giemsa staining separately. The effects of DYS on the expression level of IL-3 receptor in Baf3 cells and the expression level of c-kit in 32D cells were determinated using RT-PCR. RESULT: DYS promotes alone proliferation of Baf3 cells and 32D cells after 48 h. In contrast to control cells, 32D cells containing DYS without IL-3 form many large clusters. DYS also increases the proliferation when cultured with IL-3. High concentration of DYS induce alone the differentiation of 32D cells and increase alone the number of the polyploidy megakaryocyte. Moreover, DYS increases alone the expression level of IL-3R in Baf3 cells and the expression level of c-kit in 32D cells separately. CONCLUSION: Our data shows DYS can promote alone proliferation and differentiation of megakaryocyte progenitor cells. The proliferative and differentiative effect of DYS on megakaryocyte progenitor cells is correlated to the up-regulation of IL-3 receptor and c-kit expression.