Primary cilia support cartilage regeneration after injury / 国际口腔科学杂志·英文版

In growing children, growth plate cartilage has limited self-repair ability upon fracture injury always leading to limb growth arrest. Interestingly, one type of fracture injuries within the growth plate achieve amazing self-healing, however, the mechanism is unclear. Using this type of fracture mouse model, we discovered the activation of Hedgehog (Hh) signaling in the injured growth plate, which could activate chondrocytes in growth plate and promote cartilage repair. Primary cilia are the central transduction mediator of Hh signaling. Notably, ciliary Hh-Smo-Gli signaling pathways were enriched in the growth plate during development. Moreover, chondrocytes in resting and proliferating zone were dynamically ciliated during growth plate repair. Furthermore, conditional deletion of the ciliary core gene Ift140 in cartilage disrupted cilia-mediated Hh signaling in growth plate. More importantly, activating ciliary Hh signaling by Smoothened agonist (SAG) significantly accelerated growth plate repair after injury. In sum, primary cilia mediate Hh signaling induced the activation of stem/progenitor chondrocytes and growth plate repair after fracture injury.

Research progress on the immunomodulatory effects and mechanisms of trace amine-associated receptor 1 / 生理学报

Trace amines are endogenous molecules distributed in the central nervous system and peripheral tissues that resemble common biogenic amines in terms of subcellular localization, chemical structure, and metabolism. Trace amine-associated receptor (TAAR) is a kind of evolutionarily conserved G-protein-coupled receptors in vertebrates, in which TAAR1 is a functional regulator of monoamine transmitters such as dopamine and serotonin. TAAR1 is widely considered as a potential therapeutic target for schizophrenia, depression and drug addiction. Moreover, TAAR1 is also expressed in peripheral tissues. The homeostasis imbalance of trace aminergic system can induce over-activation of peripheral immune system and central immune inflammatory response. TAAR1 modulators are becoming potential emerging drugs for the treatment of immune-related illnesses, because they may play a major role in the activation or modulation of immune response.

Spatiotemporal Dynamics of the Molecular Expression Pattern and Intercellular Interactions in the Glial Scar Response to Spinal Cord Injury / 神经科学通报·英文版

Nerve regeneration in adult mammalian spinal cord is poor because of the lack of intrinsic regeneration of neurons and extrinsic factors - the glial scar is triggered by injury and inhibits or promotes regeneration. Recent technological advances in spatial transcriptomics (ST) provide a unique opportunity to decipher most genes systematically throughout scar formation, which remains poorly understood. Here, we first constructed the tissue-wide gene expression patterns of mouse spinal cords over the course of scar formation using ST after spinal cord injury from 32 samples. Locally, we profiled gene expression gradients from the leading edge to the core of the scar areas to further understand the scar microenvironment, such as neurotransmitter disorders, activation of the pro-inflammatory response, neurotoxic saturated lipids, angiogenesis, obstructed axon extension, and extracellular structure re-organization. In addition, we described 21 cell transcriptional states during scar formation and delineated the origins, functional diversity, and possible trajectories of subpopulations of fibroblasts, glia, and immune cells. Specifically, we found some regulators in special cell types, such as Thbs1 and Col1a2 in macrophages, CD36 and Postn in fibroblasts, Plxnb2 and Nxpe3 in microglia, Clu in astrocytes, and CD74 in oligodendrocytes. Furthermore, salvianolic acid B, a blood-brain barrier permeation and CD36 inhibitor, was administered after surgery and found to remedy fibrosis. Subsequently, we described the extent of the scar boundary and profiled the bidirectional ligand-receptor interactions at the neighboring cluster boundary, contributing to maintain scar architecture during gliosis and fibrosis, and found that GPR37L1_PSAP, and GPR37_PSAP were the most significant gene-pairs among microglia, fibroblasts, and astrocytes. Last, we quantified the fraction of scar-resident cells and proposed four possible phases of scar formation: macrophage infiltration, proliferation and differentiation of scar-resident cells, scar emergence, and scar stationary. Together, these profiles delineated the spatial heterogeneity of the scar, confirmed the previous concepts about scar architecture, provided some new clues for scar formation, and served as a valuable resource for the treatment of central nervous system injury.

Anti-pseudo-allergic components in licorice extract inhibit mast cell degranulation and calcium influx / 中国天然药物

Pseudo-allergic reactions (PARs) widely occur upon application of drugs or functional foods. Anti-pseudo-allergic ingredients from natural products have attracted much attention. This study aimed to investigate anti-pseudo-allergic compounds in licorice. The anti-pseudo-allergic effect of licorice extract was evaluated in rat basophilic leukemia 2H3 (RBL-2H3) cells. Anti-pseudo-allergic compounds were screened by using RBL-2H3 cell extraction and the effects of target components were verified further in RBL-2H3 cells, mouse peritoneal mast cells (MPMCs) and mice. Molecular docking and human MRGPRX2-expressing HEK293T cells (MRGPRX2-HEK293T cells) extraction were performed to determine the potential ligands of MAS-related G protein-coupled receptor-X2 (MRGPRX2), a pivotal target for PARs. Glycyrrhizic acid (GA) and licorice chalcone A (LA) were screened and shown to inhibit Compound48/80-induced degranulation and calcium influx in RBL-2H3 cells. GA and LA also inhibited degranulation in MPMCs and increase of histamine and TNF-α in mice. LA could bind to MRGPRX2, as determined by molecular docking and MRGPRX2-HEK293T cell extraction. Our study provides a strong rationale for using GA and LA as novel treatment options for PARs. LA is a potential ligand of MRGPRX2.

The distribution of Mas-related G protein-coupled receptor A in cerebrospinal fluid-contacting nucleus of normal rats and its up-regulation in neuropathic pain / 生理学报

This study was aimed to observe the distribution of Mas-related G protein-coupled receptor A (MrgA) in cerebrospinal fluid (CSF)-contacting nucleus of normal rats and its expression in neuropathic pain, and to provide morphological evidence for CSF-contacting nucleus to participate in neuropathic pain. The model of neuropathic pain with chronic constriction injury (CCI) of the sciatic nerve was made in Sprague-Dawley rats. The thermal withdrawal latency (TWL) and mechanical withdrawal threshold (MWT) were measured. The expressions of MrgA in the CSF-contacting nucleus were examined by double labeling with immunofluorescent staining. The results showed that on the 5th, 7th, 10th and 14th days, the values of MWT and TWL in CCI group were all lower than those in sham group (P < 0.05). MrgA was found to be distributed in CSF-contacting nucleus of normal rats; and the expression was markedly up-regulated in rats at the peak of neuropathic pain. Our data suggest that CSF-contacting nucleus may participate in neuropathic pain through the MrgA-mediated signaling pathway.

Weather and Birth Weight: Different Roles of Maternal and Neonatal GPR61 Promoter Methylation / 生物医学与环境科学（英文）

Objectives@#It is unclear whether G protein-coupled receptor 61 (GPR61) affecting body weight, plays a role in the association between birth weight and weather. This study aimed to assess the effects of prenatal weather and GPR61 on birth weight.@*Methods@#A total of 567 mother-newborn pairs were recruited in Houzhai Center Hospital during 2011-2012. We detected the maternal and neonatal GPR61 promoter methylation levels, and obtained meteorological and air pollution data.@*Results@#A positive association was observed between maternal and neonatal GPR61 methylation levels, and both of them were affected by precipitation, relative humidity (RH) and daily temperature range (DTR). Birth weight was associated negatively with RH and positively with DTR ( P < 0.05). A significant association was observed between birth weight and neonatal GPR61 methylation. We observed that maternal GPR61 methylation seemed to modify associations between weather and birth weight ( P interaction < 0.10), while neonatal GPR61 methylation mediated the effects of RH and DTR on birth weight ( P < 0.05).@*Conclusions@#Our findings revealed the significant associations among prenatal weather, GPR61 methylation and birth weight. Maternal GPR61 methylation may modify the susceptibility of birth weight to prenatal weather conditions, while neonatal GPR61 methylation may be a bridge of the effects of prenatal RH and DTR on birth weight.

Utility of GPR68 and TIL in TPF-induced chemotherapy and prognosis evaluation in middle-advanced hypopharyngeal squamous cell carcinoma / 中华耳鼻咽喉头颈外科杂志

Objective: To evaluate the roles of G Protein-Coupled Receptor 68 (GPR68) and tumor infiltrating lymphocytes (TIL) in TPF-(paclitaxel, cisplatin and 5-fluorouracil) induced chemotherapy for middle-advanced hypopharyngeal squamous cell carcinomas. Methods: A total of 31 patients with middle-advanced hypopharyngeal squamous cell carcinoma before TPF-inducted chemotherapy were enrolled from September 2012 to November 2017 in Beijing Tongren Hospital, Capital Medical University, including 28 males and 3 females, aged 43 to 71 years old. The expression of GPR68 and tumor infiltrating CD4+and CD8+T cells before chemotherapy was detected by immunohistochemical staining, and the relationships between GPR68 expression and clinical features, chemotherapy efficacy and overall survival (OS) were analyzed using t-test. Results: After 3 cycles of chemotherapy, there were 4, 14, 10 and 3 patients respectively with complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD). The positive rates of GPR68 and CD8 were 25% and 40% respectively in the effective group (CR+PR), while 50% and 15% in the ineffective group (SD+PD), with statistically significant differences between two groups (t=5.17 and 12.86,P<0.001). Linear regression analysis showed that GPR68 was negatively correlated with CD8+T cells (r=-0.64,P<0.001). There was no significant correlation between the CD4 expression and TPF efficacy (P>0.05). The mean OS was 12.5 months in patients with high-expressed GPR68 and 25.0 months in patients with low-expressed GPR68, with a statistically significant difference (P=0.005). And mean OS was 25.0 months in patients with high-expressed CD8 and 14.5 months in low-expressed CD8, with a statistically significant difference (HR=2.58, P=0.019). Cox regression analysis showed that GPR68 and CD8+T cells were significant prognostic factors (OR(95%CI)=3.27(2.46-5.97) and 1.53(0.78-1.82), all P<0.05), while CD4 had no significant effect on prognosis (P>0.05). Conclusion: GPR68 and CD8+T cells are expected to be biomarkers for evaluating the efficacy and prognosis of TPF-induced chemotherapy in patients with middle-advanced hypopharyngeal squamous cell carcinoma.

Expression and Significance of Leucine-rich Repeat-containing G-protein Coupled Receptor 5/6 in Wnt Pathway in Children with Acute Lymphoblastic Leukemia / 中国医学科学院学报

Objective To study the expression and significance of leucine-rich repeat-containing G-protein coupled receptor(LGR)5/6 in childhood acute lymphoblastic leukemia(ALL). Methods A total of 39 children who had ALL and achieved complete remission on day 33 after induction therapy were enrolled.The children before induction therapy were considered as the incipient group,and those who achieved complete remission on day 33 by induction therapy were considered as the remission group.According to the degree of risk,they were assigned into 3 groups:low-risk(

Regulation effect of lipopolysaccharide on the alternative splicing and function of sweet taste receptor T1R2 / 华西口腔医学杂志

OBJECTIVES@#To identify the alternative splicing isoform of mouse sweet taste receptor T1R2, and investigate the effect of lipopolysaccharide (LPS) local injection on T1R2 alternative splicing and the function of sweet taste receptor as one of the bacterial virulence factors.@*METHODS@#After mouse taste bud tissue isolation was conducted, RNA extraction and reverse transcription polymerase chain reaction (PCR) were performed to identify the splicing isoform of T1R2. Heterologous expression experiments @*RESULTS@#T1R2 splicing isoform T1R2_Δe3p formed sweet taste receptors with T1R3, which could not be activated by sweet taste stimuli and significantly downregulated the function of canonical T1R2/T1R3. Local LPS injection significantly increased the expression ratio of T1R2_Δe3p in mouse taste buds.@*CONCLUSIONS@#LPS stimulation affects the alternative splicing of mouse sweet taste receptor T1R2 and significantly upregulates the expression of non-functional isoform T1R2_Δe3p, suggesting that T1R2 alternative splicing regulation may be one of the mechanisms by which microbial infection affects host taste perception.

Clinical implication of xenotropic and polytropic retrovirus receptor 1 in papillary thyroid carcinoma / 浙江大学学报·医学版

To investigate the expression of xenotropic and polytropic retrovirus receptor 1 （） in papillary thyroid cancer （PTC） and its clinical implication. The HPA and UALCAN databases were used to explore the expression of XPR1 in PTC and normal tissues. The cBioPortal database was used to obtain the clinical data of PTC patients and gene expression profile. The correlation of expression with gender，age，sub-types，T stage，N stage，M stage and clinical stage of patients were analyzed. Cox regression was conducted to analysis the factors affecting the prognosis of PTC patients. The mutation of was assessed through cBioPortal database. GO and KEGG analyses were used to explore the related biological pathway of involved in PTC. HPA database analysis showed that XPR1 was highly expressed in PTC tissue compared with normal tissues. UALCAN analysis displayed that expression was significantly higher in PTC tissue compared with normal tissues （0.05）. Cox regression analysis showed that was an independent prognostic factor of PTC patients （=2.894，<0.05）. The cBioPortal database indicated that the mutation appeared in 6% PTC patients; the mutation type mainly was missense and the mutation point was located at the E615K. Enrichment analysis indicated that might affect the PTC progression through involvement in metabolic pathway. is highly expressed in PTC tissues，which is associated with the prognosis of patients. Metabolic pathway associated with might play an important role in PTC progression，indicating that might be a novel biomarker for diagnosis and treatment of PTC.

New effect of G-protein coupled receptors on blood pressure regulation / 中国中药杂志

Hypertension is a clinical syndrome characterized by elevated systemic arterial blood pressure, which may be accompanied by functional or organic damage of heart, brain, kidney and other organs. The pathogenesis and development of hypertension are affected by genetic, environmental, epigenetic, intestinal microbiota and other factors. They are the result of multiple factors that promote the change of blood pressure level and vascular resistance. G protein coupled receptors(GPCRs) are the largest and most diverse superfamily of transmembrane receptors that transmit signals across cell membranes and mediate a large number of cellular responses required by human physiology. A variety of GPCRs are involved in the control of blood pressure and the maintenance of normal function of cardiovascular system. Hypertension contributes to the damages of heart, brain, kidney, intestine and other organs. Many GPCRs are expressed in various organs to regulate blood pressure. Although many GPCRs have been used as therapeutic targets for hypertension, their efficacy has not been fully studied. The purpose of this paper is to elucidate the role of GPCRs in blood pressure regulation and its distribution in target organs. The relationship between GPCRs related to intestinal microorganisms and blood pressure is emphasized. It is proposed that traditional Chinese medicine may be a new way to treat hypertension by regulating the related GPCRs via intestinal microbial metabolites.

Tauroursodeoxycholic acid attenuates neuronal apoptosis via the TGR5/ SIRT3 pathway after subarachnoid hemorrhage in rats

BACKGROUND: Neuronal apoptosis plays a critical event in the pathogenesis of early brain injury after subarachnoid hemorrhage (SAH). This study investigated the roles of Tauroursodeoxycholic acid (TUDCA) in attenuate neuronal apoptosis and underlying mechanisms after SAH. METHODS: Sprague-Dawley rats were subjected to model of SAH and TUDCA was administered via the internal carotid injection. Small interfering RNA (siRNA) for TGR5 were administered through intracerebroventricular injection 48 h before SAH. Neurological scores, brain water content, Western blot, TUNEL staining and immunofluorescence staining were evaluated. RESULTS: TUDCA alleviated brain water content and improved neurological scores at 24 h and 72 h after SAH. TUDCA administration prevented the reduction of SIRT3 and BCL-2 expressions, as well as the increase of BAX and cleaved caspase-3.Endogenous TGR5 expression were upregulated after SAH and treatment with TGR5 siRNA exacerbated neurological outcomes after SAH and the protective effects of TUDCA at 24 h after SAH were also abolished by TGR5 siRNA. CONCLUSIONS: Our findings demonstrate that TUDCA could attenuated neuronal apoptosis and improve neurological functions through TGR5/ SIRT3 signaling pathway after SAH. TUDCA may be an attractive candidate for anti-apoptosis treatment in SAH.

Effects of ICI 182, 780, an ERα and ERß antagonist, and G-1, a GPER agonist, on autophagy in breast cancer cells / Efeitos do antagonista seletivo do REα e do REß ICI 182, 780 e do agonista de GPER G-1 no processo de autofagia em células de câncer de mama

ABSTRACT Objective To investigate if ICI 182,780 (fulvestrant), a selective estrogen receptor alpha/beta (ERα/ERβ) antagonist, and G-1, a selective G-protein-coupled receptor (GPER) agonist, can potentially induce autophagy in breast cancer cell lines MCF-7 and SKBr3, and how G-1 affects cell viability. Methods Cell viability in MCF-7 and SKBr3 cells was assessed by the MTT assay. To investigate the autophagy flux, MCF-7 cells were transfected with GFP-LC3, a marker of autophagosomes, and analyzed by real-time fluorescence microscopy. MCF-7 and SKBr3 cells were incubated with acridine orange for staining of acidic vesicular organelles and analyzed by flow cytometry as an indicator of autophagy. Results Regarding cell viability in MCF-7 cells, ICI 182,780 and rapamycin, after 48 hours, led to decreased cell proliferation whereas G-1 did not change viability over the same period. The data showed that neither ICI 182,780 nor G-1 led to increased GFP-LC3 puncta in MCF-7 cells over the 4-hour observation period. The cytometry assay showed that ICI 182,780 led to a higher number of acidic vesicular organelles in MCF-7 cells. G-1, in turn, did not have this effect in any of the cell lines. In contrast, ICI 182,780 and G-1 did not decrease cell viability of SKBr3 cells or induce formation of acidic vesicular organelles, which corresponds to the final step of the autophagy process in this cell line. Conclusion The effect of ICI 182,780 on increasing acidic vesicular organelles in estrogen receptor-positive breast cancer cells appears to be associated with its inhibitory effect on estrogen receptors, and GPER does notseem to be involved. Understanding these mechanisms may guide further investigations of these receptors' involvement in cellular processes of breast cancer resistance.

RESUMO Objetivo Avaliar o efeito dos compostos ICI 182,780 (fulvestranto), um antagonista seletivo dos receptores de estrógeno alfa/beta (REα/REβ), e do G-1, um agonista seletivo de receptores de estrógeno acoplados a proteínas-G (GPER), na possível indução de autofagia em linhagens de câncer de mama MCF-7 e SKBr3, bem como o efeito de G-1 na viabilidade celular. Métodos A viabilidade celular de células MCF-7 e SKBr3 foi avaliada pelo ensaio com MTT. Para investigar a indução da autofagia, células MCF-7 foram transfectadas com GFP-LC3, um marcador de autofagossomos, e analisadas por microscopia de fluorescência em tempo real. As células MCF-7 e SKBr3 foram incubadas com o indicador de compartimentos ácidos laranja de acridina e analisadas por citometria de fluxo como indicativo para autofagia. Resultados Em células MCF-7, o ICI 182,780 e rapamicina após 48 horas levaram à diminuição da viabilidade celular, enquanto o G-1 não alterou a viabilidade no mesmo período de tratamento. Nem o ICI 182,780 e nem o G-1 induziram aumento na pontuação de GFP-LC3 em células MCF-7 até 4 horas. Já os ensaios de citometria de fluxo demonstraram que ICI 182,780 levou ao aumento de compartimentos ácidos em células MCF-7. O G-1 não aumentou estes parâmetros em ambas as linhagens. Por outro lado, ICI 182,780 e G-1 não induziram à redução da viabilidade em células SKBr3 e nem à formação de compartimentos ácidos, como etapa final do processo autofágico. Conclusão O aumento de compartimentos ácidos pelo ICI 182,780 em células de câncer de mama positivas para receptores de estrógeno parece estar associado com seu efeito inibidor de receptores de estrógeno, mas sem o envolvimento de GPER. A compreensão desses mecanismos pode direcionar estudos sobre o envolvimento dos receptores nos processos celulares de resistência do câncer de mama.

Association of taste receptor gene polymorphisms with dental caries

Abstract This study was performed to evaluate the interplay between dental caries, nutritional status, and genetic polymorphisms in TAS1R1 and TAS1R2 (taste receptor, type 1, member 1 and 2) in preschool children and pre-adolescents. We included 525 subjects (306 preschool children and 219 pre-adolescents). Parents/caregivers answered a self-administered questionnaire about their children's systemic health, characteristics, oral hygiene habits, and diet. Clinical examination was performed to evaluate dental caries and nutritional status. Saliva samples were collected for DNA extraction. The genotyping of rs17492553 ( TAS1R1 ), rs3935570, and rs4920566 ( TAS1R2 ) polymorphisms was performed using real-time PCR with Taqman Genotyping Master Mix and SNP assay. Both univariate and multivariate Poisson regression analyses with robust variance were used for the data analysis. In preschool children, consumption of sweets between meals increased the prevalence of dental caries by 85% (PR c = 1.85; 95%CI 1.39-2.46; p < 0.001), whereas in pre-adolescents, this prevalence increased by 34% (PR a = 1.34; 95%CI 1.11-1.62; p = 0.002), regardless of genetic polymorphisms . Moreover, individuals carrying at least one allele C in rs17492553 presented 23% more prevalence of dental caries (PR a = 1.23; 95%CI 1.02-1.49 p = 0.030). Nutritional status was not associated with dental caries, neither with genetic polymorphisms . Consumption of sweets between meals increased the prevalence of dental caries. In pre-adolescents, rs17492553 genetic polymorphism in TAS1R1 was associated with dental caries.

Advances on the role of primary cilia in neurological diseases / 生理学报

Primary cilium, widely distributed in mammalian central nervous system, is an important extracellular organelle of cells. The primary cilia contain a variety of ion channels, G-protein coupled receptors and different kinds of kinases, which indicates that primary cilia can detect extracellular signals and transduce them into cells to regulate various cellular and physiological processes. In humans, mutations of genes related to structure and function of primary cilia always cause various monogenetic diseases. Moreover, a series of neuropsychiatric diseases and neurodevelopmental dysplasia are caused by abnormal functions of G-protein coupled receptors, kinases and ion channels in primary cilia. This article reviews recent research progress on the role of primary cilia in related neurological diseases.

Taurochenodeoxycholic acid mediates cAMP-PKA-CREB signaling pathway / 中国天然药物

Taurochenodeoxycholic acid (TCDCA) is one of the main effective components of bile acid, playing critical roles in apoptosis and immune responses through the TGR5 receptor. In this study, we reveal the interaction between TCDCA and TGR5 receptor in TGR5-knockdown H1299 cells and the regulation of inflammation via the cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA)-cAMP response element binding (CREB) signal pathway in NR8383 macrophages. In TGR5-knockdown H1299 cells, TCDCA significantly activated cAMP level via TGR5 receptor, indicating TCDCA can bind to TGR5; in NR8383 macrophages TCDCA increased cAMP content compared to treatment with the adenylate cyclase (AC) inhibitor SQ22536. Moreover, activated cAMP can significantly enhance gene expression and protein levels of its downstream proteins PKA and CREB compared with groups of inhibitors. Additionally, TCDCA decreased tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, IL-8 and IL-12 through nuclear factor kappa light chain enhancer of activated B cells (NF-κB) activity. PKA and CREB are primary regulators of anti-inflammatory and immune response. Our results thus demonstrate TCDCA plays an essential anti-inflammatory role via the signaling pathway of cAMP-PKA-CREB induced by TGR5 receptor.

Effect of pranlukast on neonatal rats with periventricular leukomalacia / 中国当代儿科杂志

OBJECTIVE@#To study the effect of pranlukast (Pran) on neonatal rats with periventricular leukomalacia (PVL).@*METHODS@#The rats, aged 3 days, were randomly divided into a sham-operation group, a PVL group, and a Pran group. A rat model of PVL was prepared by right common carotid artery ligation and postoperative hypoxia. The rats in the sham-operation group were given isolation of the right common carotid artery without ligation or hypoxic treatment. The rats in the Pran group were given intraperitoneal injection of Pran (0.1 mg/kg) once every 12 hours, for 3 consecutive days, and those in the sham-operation group and the PVL group were given intraperitoneal injection of an equal volume of normal saline. On day 14 after modeling, hematoxylin-eosin (HE) staining was used to observe the pathological changes of brain tissue; immunofluorescent staining was used to measure the expression of myelin basic protein (MBP) in brain tissue (n=8); Western blot was used to measure the expression of cyclic nucleotide phosphodiesterase (CNPase), MBP, and G protein-coupled receptor 17 (GPR17) (n=8). On day 21 after modeling, Morris water maze test was used to evaluate the learning and memory abilities of rats in each group (n=8).@*RESULTS@#The results of HE staining showed that the PVL group had greater pathological changes of white matter than the sham-operation group, and compared with the PVL group, the Pran group had a significant improvement in such pathological changes. The results of immunofluorescence assay showed that the PVL group had a lower mean fluorescence intensity of MBP than the sham-operation group (P<0.05), and the Pran group had a higher mean fluorescence intensity of MBP than the PVL group (P<0.05). Western blot showed that compared with the sham-operation group, the PVL group had significantly lower relative expression of MBP and CNPase (P<0.05) and significantly higher relative expression of GPR17 (P<0.05), and compared with the PVL group, the Pran group had significantly higher relative expression of MBP and CNPase (P<0.05) and significantly lower relative expression of GPR17 (P<0.05). Morris water maze test showed that compared with the sham-operation group, the PVL group had a significant increase in escape latency and a significant reduction in the number of platform crossings, and compared with the PVL group, the Pran group had a significant reduction in escape latency and a significant increase in the number of platform crossings (P<0.05).@*CONCLUSIONS@#Pran can alleviate brain damage, promote myelination, and improve long-term learning and memory abilities in neonatal rats with PVL, possibly by reducing the expression of GPR17.

Palmitic acid-induced lipotoxicity promotes a novel interplay between Akt-mTOR, IRS-1, and FFAR1 signaling in pancreatic ß-cells

BACKGROUND: Free fatty acid receptor 1 (FFAR1) is G-protein coupled receptor predominantly expressed in pancreatic ß-cells that is activated by a variety of free fatty acids (FFAs). Once activated, it promotes glucose-stimulated insulin secretion (GSIS). However, increased levels of FFAs lead to lipotoxicity, inducing loss of ß-cell function. FFAR1 plays a key role in the development of type 2 diabetes (T2D), and previous studies have indicated the importance of developing anti-diabetic therapies against FFAR1, although its role in the regulation of ß-cell function remains unclear. The present study investigated the role of FFAR1 under lipotoxic conditions using palmitic acid (PA). The rat insulinoma 1 clone 832/13 (INS-1 832/13) cell line was used as a model as it physiologically resembles native pancreatic ß-cells. Key players of the insulin signaling pathway, such as mTOR, Akt, IRS-1, and the insulin receptor (INSR1ß), were selected as candidates to be analyzed under lipotoxic conditions. RESULTS: We revealed that PA-induced lipotoxicity affected GSIS in INS-1 cells and negatively modulated the activity of both IRS-1 and Akt. Reduced phosphorylation of both IRS-1 S636/639 and Akt S473 was observed, in addition to decreased expression of both INSR1ß and FFAR1. Moreover, transient knockdown of FFAR1 led to a reduction in IRS-1 mRNA expression and an increase in INSR1ß; mRNA. Finally, PA affected localization of FFAR1 from the cytoplasm to the perinucleus. CONCLUSIONS: In conclusion, our study suggests a novel regulatory involvement of FFAR1 in crosstalk with mTOR-Akt and IRS-1 signaling in ß-cells under lipotoxic conditions.

Next-Generation Tools to Study Autonomic Regulation In Vivo / 神经科学通报·英文版

The recent development of tools to decipher the intricacies of neural networks has improved our understanding of brain function. Optogenetics allows one to assess the direct outcome of activating a genetically-distinct population of neurons. Neurons are tagged with light-sensitive channels followed by photo-activation with an appropriate wavelength of light to functionally activate or silence them, resulting in quantifiable changes in the periphery. Capturing and manipulating activated neuron ensembles, is a recently-designed technique to permanently label activated neurons responsible for a physiological function and manipulate them. On the other hand, neurons can be transfected with genetically-encoded Ca indicators to capture the interplay between them that modulates autonomic end-points or somatic behavior. These techniques work with millisecond temporal precision. In addition, neurons can be manipulated chronically to simulate physiological aberrations by transfecting designer G-protein-coupled receptors exclusively activated by designer drugs. In this review, we elaborate on the fundamental concepts and applications of these techniques in research.

Understanding Bile Acid Signaling in Diabetes: From Pathophysiology to Therapeutic Targets

Diabetes and obesity have reached an epidemic status worldwide. Diabetes increases the risk for cardiovascular disease and non-alcoholic fatty liver disease. Primary bile acids are synthesized in hepatocytes and are transformed to secondary bile acids in the intestine by gut bacteria. Bile acids are nutrient sensors and metabolic integrators that regulate lipid, glucose, and energy homeostasis by activating nuclear farnesoid X receptor and membrane Takeda G protein-coupled receptor 5. Bile acids control gut bacteria overgrowth, species population, and protect the integrity of the intestinal barrier. Gut bacteria, in turn, control circulating bile acid composition and pool size. Dysregulation of bile acid homeostasis and dysbiosis causes diabetes and obesity. Targeting bile acid signaling and the gut microbiome have therapeutic potential for treating diabetes, obesity, and non-alcoholic fatty liver disease.