脑室内注射5,7-双羟色胺对内侧前额叶皮层锥体神经元5-HT_(1A)受体敏感性的影响

目的：探讨脑室内注射5，7-双羟色胺（5，7-DHT）对内侧前额叶皮层（mPFC）锥体神经元5-羟色胺-1A（5-HT1A）受体敏感性的影响，阐明5-HT1A受体对锥体神经元电活动的作用。方法：36只雄性SD大鼠随机分为假手术组（n＝21）和5，7-DHT损毁组（n＝15）。损毁组大鼠脑室内注射5，7-DHT，假手术组大鼠脑室内注射同等剂量生理盐水，2组大鼠静脉注射不同剂量（0.5～128.0μg·kg-1）5-HT1A受体激动剂8-OH-DPAT，采用体细胞外电生理学方法观察mPFC中锥体神经元放电频率的变化，并静脉注射5-HT1A受体拮抗剂 WAY100635，观察损毁组大鼠对5，7-DHT激动剂和拮抗剂的敏感性，并与假手术组进行比较。结果：在假手术组中，不同剂量（0.5～128.0μg·kg-1）8-OH-DPAT对大鼠锥体神经元的放电频率均产生兴奋-抑制式的影响，这些神经元在低剂量（0.5～32.0μg·kg-1）时被兴奋，放电频率增加（P＜0.05）；而在高剂量（128.0μg·kg-1）时则被抑制，放电频率减少。在损毁组中，不同剂量（0.5～128.0μg·kg-1）8-OH-DPAT剂量依赖性地抑制大鼠锥体神经元的电活动（df＝5，F＝3.44，P ＝0.003），即放电频率减少，未见兴奋-抑制效应；WAY10035可以反转8-OH-DPAT的抑制作用。结论：脑室内注射5，7-DHT可使大鼠mPFC锥体神经元5-HT1A受体敏感性降低。

Rivastigmine Restores 5-HT_1AReceptor Levels in the Hippocampus of Olfactory Bulbectomized Mice

Rivastigmine, a dual acetylcholinesterase and butyrylcholinesterase inhibitor, is used for symptomatic treatment of patients with mild to moderately severe dementia in Alzheimer’s disease (AD) patients. In the present study, we found that 5-HT1A receptor (5-HT1AR) is downregulated, whereas 5-HT2A receptor (5-HT2AR) is upregulated in the hippocampal dentate gyrus (DG) and CA1 region by olfactory bulbectomy (OBX) in mice. Furthermore, chronic treatment with rivastigmine (1.0 mg/kg) for 2 weeks starting 2 weeks after OBX operation restored the decreased 5-HT1AR and the increased 5-HT2AR levels. To determine whether cholinergic receptor stimulation by rivastigmine is involved in the rivastigmine-induced regulation of 5-HTR levels, we treated the mice with mecamylamine (2.5 mg/kg), or atropine (5.0 mg/kg) with rivastigmine (1.0 mg/kg) once a day for 2 weeks. Notably, the rivastigmine-induced 5-HT1AR upregulation was eliminated by mecamylamine but not by atropine treatments. On the other hand, the restored 5-HT2AR level by rivastigmine was not affected by either mecamylamine or atropine. Treatment with 8-OH-DPAT, a selective 5-HT1AR agonist improved the decreased 5-HT1AR and the increased 5-HT2AR levels in OBX mice. On the other hand, treatment with TCB-2, a potent 5-HT2AR agonist had no effects on the 5-HT1AR and 5-HT2AR dysregulation in OBX mice. Taken together, nicotinic acetylcholine receptor (nAChR) stimulation mediates rivastigmine-induced upregulation of 5-HT1AR. Therefore, we speculate that the increased ACh levels by rivastigmine can stimulate nAChR located on serotonergic nerve terminals and stimulate 5-HT1AR by the enhanced 5-HT release in the hippocampus. The 5-HT1AR stimulation likely mediates the improvement of 5-HT1AR levels as auto-receptor in OBX hippocampus.

Effects of Activation and Blockade of Serotonin 5-HT1A Receptors on the Immune Response in Rats Selected for Different Levels of Aggressiveness

The present study examines the effects of serotonin (5-HT) 1A receptor ligands on humoral im-mune response in two rat lines selected for over 75 generations for the enhancement or elimination of aggression. Activation of presynaptic 5-HT1A receptors with a low dose of the selective 5-HT1A receptor agonist 8-OH-DPAT (0.1 mg/kg) or the blockade of postsynaptic 5-HT1A receptors with the antagonist WAY-100635 (1.0 mg/kg) did not affect the numbers of IgM-antibody forming cells (IgM-AFC) in the spleen of highly aggressive rats, which were characterized by higher immune responsiveness compared to nonaggressive line. On the other hand, the same doses of 8-OH-DPAT and WAY-100635, as well as a higher dose of 8-OH-DPAT (1.0 mg/kg), which is known to activate postsynaptic 5-HT1A receptors, produce immunostimulation in nonaggressive rats. However, only the highest dose of 8-OH-DPAT (5.0 mg/kg) was able to cause immunosuppression in nonaggressive rats that was mainly dependent on stimulation of postsynaptic 5-HT1A receptors. In contrast to nonaggressive rats, the dose of 1.0 mg/kg 8-OH-DPAT was sufficient to produce a decrease in the numbers of IgM-AFC in highly aggressive rats. Thus, pharmacological activation of pre- and postsynaptic 5-HT1A receptors, as well as the blockade of postsynaptic 5-HT1A receptors, produced different effects on the immune response in two lines of rats selected for high level of aggression or its absence. These data may have implications for more efficient treatments of a number of mental disorders associated with abnormal aggression.

Molecular signaling of 5-HT_1Aand presence of serotonergic cells in the fetal cerebral cortex

Early appearance of the serotonergic system in the fetal brain and the various effects of serotonin (5-HT) on brain morphogenesis, have given support to a neurotrophic role of serotonin. This function of serotonin is accomplished through a system of serotonin nerve terminals in the target regions that involves various 5-HT receptors. In visual, auditory and somatosensory cortex an early and intense serotonergic innervation is particularly important. The neuronal somata of these terminals are normally located in the mesencephalon and they have not been observed in the maturing cerebral cortex, neither in the adult brain. By using immunolabeling techniques, fluorescence and confocal microscopy, we observe the presence of both, 5-HT terminals and 5-HT cells in mesencephalon (Me, E17) and in the neopallium (Np, E13-E16) cocultures. Cells immunopositive to 5-HT and to tryptophan-5-hydroxilase are also observed in the Np on day 12 of culture. These results concerning the unexpected presence of serotonergic cells in the fetal cerebral cortex are interesting and may be of importance in corticogenesis. As it happens with other elements of the serotonergic system, the presence of these phenotypically serotonergic cells in the early cerebral cortex may be transitory and probably supporting cortex maturation processes. The molecular signaling path of the 5-HT1A receptor has also been identified.

Uromedic^(■) Pumpkin Seed Derived Δ7-Sterols, Extract and Oil Inhibit 5α-Reductases and Bind to Androgen Receptor in Vitro

Dihydrotestosterone (DHT) is implicated in the development of benign prostate hyperplasia (BPH). We investigated if Uromedic? pumpkin (variety of Cucurbita pepo L. convar. citrullinina GREB. var. styriaca GREB) seed soft extract (active ingredients of GRANUFINK? Prosta forte 500 mg), seed oil and isolated Δ7-sterols could inhibit the conversion of [1,2,6,7-3H(N)]-testosterone to DHT by 5α-reductases. Also, we tested competition with [3H]-DHT for binding to the androgen receptor (AR). Pumpkin seed oil and pumpkin seed soft extract were identified as moderately active inhibitors of 5α-R1 and 5α-R2, with almost similar inhibitory capacities (IC50 5 mg/ml for 5α-R1 and about IC50 = 6 mg/ml for 5α-R2). The isolated Δ7-sterols were more active inhibitors (IC50 = 0.3 mg/ml for 5α-R1, IC50 = 1.0 mg/ml for 5α-R2). All three test compounds bound to the AR dose-dependently, with strong binding by Δ7-sterols (IC50 = 0.2 mg/ml) and weaker binding by pumpkin seed oil (IC50 = 0.4 mg/ml) and pumpkin seed soft extract (IC50 = 1.1 mg/ml). We propose that inhibition of 5α-reductases and competitive binding to the AR are mechanisms of action, by which the Uromedic? pumpkin seed derived test compounds, most specifically Δ7-sterols, counteract DHT and thereby exert clinically positive effects on the prostate, as well as bladder-strengthening effects.

Sleep Deprivation Selectively Down-Regulates Astrocytic 5-HT2B Receptors and Triggers Depressive-Like Behaviors via Stimulating P2X7 Receptors in Mice

Chronic loss of sleep damages health and disturbs the quality of life.Long-lasting sleep deprivation(SD)as well as sleep abnormalities are substantial risk factors for major depressive disorder,although the underlying mechanisms are not clear.Here,we showed that chronic SD in mice promotes a gradual elevation of extracellular ATP,which activates astroglial P2X7 receptors(P2X7Rs).Activated P2X7Rs,in turn,selectively down-regulated the expression of 5-HT2B receptors(5-HT2BRs)in astrocytes.Stimulation of P2X7Rs induced by SD selectively suppressed the phosphorylation of AKT and FoxO3 a in astrocytes,but not in neurons.The overexpression of FoxO3a in astrocytes inhibited the expression of 5-HT2BRs.Down-regulation of 5-HT2BsRs instigated by SD suppressed the activation of STAT3 and relieved the inhibition of Ca2+-dependent phospholipase A2.This latter cascade promoted the release of arachidonic acid and prostaglandin E2.The depression-like behaviors induced by SD were alleviated in P2X7R-KO mice.Our study reveals the mechanism underlying chronic SD-induced depression-like behaviors and suggests 5-HT2BRs as a key target for exploring therapeutic strategies aimed at the depression evoked by sleep disorders.

Synthesis and biological evaluation of ^(99m)Tc-HEDTA/HYNIC-MPP4 complex for 5-HT1A receptor imaging

5-HT1A receptor is associated with a variety of pathophysiology of neuropsychiatric disorders. Accordingly, we have synthesized a new 5-HT1A receptor ligand (HYNIC-MPP4) and labeled it with 99mTc using N-(2-hydroxyethyl)ethylenediaminetriacetic acid (HEDTA) as coligand. 99mTc-HEDTA/HYNIC-MPP4 was prepared under pH 6 at room temperature. Biodistribution of 99mTc-HEDTA/HYNIC-MPP4 in normal mice showed that this complex had moderate brain uptake (0.60% ID·g-1 at 2 min p.i.) and good retention. The hippocampus had the highest radioactivity uptake at 2 min p.i. (1.84% ID·g-1). The ratio of Hipp/CB was 3.1 at 2 min p.i. and increased to 4.4 at 60 min p.i. After blocking with 8-hydroxy-2-(dipropylamino) tetralin, the uptake of hippocampus was decreased significantly from 1.84% ID·g-1 to 0.53% ID·g-1 at 2 min p.i., while the cerebellum had no significant decrease. This 99mTc complex could be a potent agent for 5-HT1A receptor imaging.

7-氯-5-氧代-2,3,4,5-四氢-1H-1-苯并氮的合成

5-氯-2-硝基苯甲酸先还原、再酯化得到2-氨基-5-氯苯甲酸甲酯,然后经磺酰化、N-烷基化得5-氯-2-[N-(3-乙氧羰基丙基)-N-(对甲苯磺酰基)]氨基苯甲酸甲酯,再经Dieckmann缩合、在硫酸中同时脱羧和脱磺酰基得到托伐普坦关键中间体7-氯-5-氧代-2,3,4,5-四氢-1H-1-苯并氮,总收率约71%。

促肾上腺皮质激素释放激素1型受体拮抗剂CP154,526潜在靶点预测研究

目的虚拟筛选促肾上腺皮质激素释放激素1型受体拮抗剂(CP154,526)的潜在作用靶点。方法本研究以CP154,526为研究对象,以PharmMapper服务器为工具,采用反向分子对接法筛选它的潜在靶点,并采用PyRx 0.8软件中Autodock vina进行正向分子对接验证。结果靶蛋白转甲状腺素蛋白(TTR)与CP154,526的打分排前,它们的药效团分子特征一致。CP154,526与TTR的核心氨基酸有相互作用。结论 TTR可能是CP154,526的作用靶蛋白之一。

Up to date on cholesterol 7 alpha-hydroxylase (CYP7A1) in bile acid synthesis

Cholesterol 7 alpha-hydroxylase(CYP7A1,EC1.14)is the first and rate-limiting enzyme in the classic bile acid synthesis pathway.Much progress has been made in understanding the transcriptional regulation of CYP7A1 gene expression and the underlying molecular mechanisms of bile acid feedback regulation of CYP7A1 and bile acid synthesis in the last three decades.Discovery of bile acid-activated receptors and their roles in the regulation of lipid,glucose and energy metabolism have been translated to the development of bile acid-based drug therapies for the treatment of liver-related metabolic diseases such as alcoholic and non-alcoholic fatty liver diseases,liver cirrhosis,diabetes,obesity and hepatocellular carcinoma.This review will provide an update on the advances in our understanding of the molecular biology and mechanistic insights of the regulation of CYP7A1 in bile acid synthesis in the last 40 years.

Pattern of triptans use: a retrospective prescription study in Calabria, Italy

Triptans are 5-hydroxytryptamine 1 B/1 D receptor agonists used in moderate to severe migraine attacks as first line when non-specific,symptomatic,nonsteroidal anti-inflammatory drugs are not effective.To gain insight in the treatment of migraine in the regional context,this retrospective(from January to August of the years 2017 and 2018)study aimed at monitoring the use of triptans approved by the regional health authority in Calabria.The data demonstrate that the overall treatment of migraine with triptans in the different provinces of Calabria falls in the average regional prescription/dispensation.Interestingly,Crotone showed a trend to an increased amount of defined daily dose/1000 inhabitants per day.The present analysis might stand for homogeneity of treatment of migraineurs in Calabria and highlights the need for better understanding the apparent differences in the local pattern of almotriptan use to improve the appropriateness.

Behavioral Characteristics of Pharmacologically Selected Lines of Rats: Relevance to Depression

This brief review discusses the behavioral consequences of two pharmacologically selected lines of rats. Flinders Sensitive (FSL) and Flinders Resistant (FRL) Lines of rats were selected on the basis of differential hypothermic and behavioral responses to the anticholinesterase, diisopropylfluorophosphate (DFP). FSL rats are more sensitive to the hypothermic effects of cholinergic, serotonergic, and dopaminergic agonists but less sensitive to the locomotor or stereotypic effects of dopamine agonists. FSL rats exhibit greater immobility in the forced swim test and reduced social interaction compared with FRL rats, but do not differ in saccharin intake, behavior in the elevated plus maze, or responses for rewarding brain self-stimulation. The exaggerated immobility and reduced social interaction are counteracted by chronic treatment with antidepressants. Because FSL rats were more sensitive to 5-HT1A receptor agonists, high (HDS) and low (LDS) 8-OH-DPATsensitive lines were selectively bred for differential hypothermic responses to the 5-HT1A receptor agonist, 8-hydroxy-2-(di-N-propylamino)tetralin (8-OH-DPAT). HDS rats were also more sensitive to the hypothermic effects of oxotremorine, a cholinergic agonist, but selection for this response did not diverge with later selection. HDS rats exhibited greater immobility in the forced swim test than LDS rats and this correlated response could be seen early in selection (generation 3). HDS rats also showed reduced social interaction compared to LDS rats, but did not differ in behavior in the elevated plus maze. These findings confirm that selection for hypothermic responses to pharmacological agents do have behavioral consequences, notably the production of depressive-like phenotypes, which can be counteracted by chronic antidepressant treatment. Because increased 5-HT1A receptor sensitivity was common to both selected lines (FSL and HDS), neurobiological processes dependent on this receptor could contribute to the abnormal behaviors that manifest in these rat lines and thus suggesting a mechanism underlying depressive behaviors in humans. However, available human data are inconsistent with this hypothesis and suggest that other mechanisms underlie these behavioral abnormalities in HDS and FSL rats. These mechanisms as well as additional behavioral testing in these rat lines will be discussed.

Clinical Research on Alzheimer's Disease: Progress and Perspectives

Alzheimer's disease(AD), the most common type of dementia, is becoming a major challenge for global health and social care. However, the current understanding of AD pathogenesis is limited, and no early diagnosis and disease-modifying therapy are currently available. During the past year, significant progress has been made in clinical research on the diagnosis, prevention, and treatment of AD.In this review, we summarize the latest achievements,including diagnostic biomarkers, polygenic hazard score,amyloid and tau PET imaging, clinical trials targeting amyloid-beta(Ab), tau, and neurotransmitters, early intervention, and primary prevention and systemic intervention approaches, and provide novel perspectives for further efforts to understand and cure the disease.

Pheromone 3kPZS evokes context-dependent serotonin sexual dimorphism in the brain of the sea lamprey (Petromyzon marinus)

Mature male sea lampreys(Petromyzon marinus)release a sex pheromone,3-keto-petromyzonol sulfate(3kPZS),that induces sexually dimorphic behavioral responses in conspecifics.However,the neural mechanism of such responses is mostly unknown.We examined the neurotransmitter serotonin(5-hydroxytryptamine,5-HT)and the expression of 5-HT1A receptors in the forebrain and brainstem of sea lamprey exposed to the vehicle(0.91 ppm methanol)or 10−10 M 3kPZS for 2 h using high performance liquid chromatography-electrospray ionization tandem mass spectrometry,immunohistochemistry and real-time quantitative polymerase chain reaction.Exposure to 3kPZS for 2 h increased 5-HT concentration in the forebrain of adult females,whereas 5-HT was not detected in the forebrain of adult males.On the contrary,3kPZS exposure decreased 5-HT concentration in the brainstem of adult females and had no effect in adult males.Pheromone exposure evoked context-dependent sexual dimorphism in brain 5-HT1A receptor immunoreactivity,but had no effect on 5-HT1A mRNA concentrations in the brain with 2 h exposure time.It appears that in sea lamprey pheromone 3kPZS affects the 5-HT system in the brain in a context-dependent,sexually dimorphic manner.