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The cell-type-specific response of neural cells to oxidative stress, a crucial mechanism for accelerating aging and cognitive dysfunction in Alzheimer's disease (AD), is still far from understood. Here, we employed human-induced pluripotent stem cells (hiPSCs)-derived neural stem cells (hiPSC-NSCs), neurons (hiPSC-Neurons), and microglia-like cells (hiPSC-MGLs) from sporadic AD (sAD) patients, age-matched cognitive normal controls (CNCs), and young subjects to observe human neural cell-type response to H2O2 stimulation. Without H2O2 exposure, reactive oxygen species (ROS) cannot be detected in hiPSC-NSCs from all three groups, but the viability of hiPSC-NSCs from AD patients was significantly lower than those of CNCs and young subjects. There were no significant differences in ROS, viabilities, neurite length, and neurite branch points in hiPSC-Neurons among three groups. No significant differences in viabilities, phagocytosis, and secretion of cytokines were observed in hiPSC-MGLs among three groups, but higher ROS levels in sAD hiPSC-MGLs. Under H2O2 exposure, the viability, neurite length, and neurite branch points of hiPSC-Neurons from AD patients reduced more significantly accompanied by more ROS release. H2O2 exposure caused hiPSC-MGLs from AD patients to release more ROS, cytokines, and stronger phagocytosis. Nevertheless, H2O2 exposure had no effect on viability of hiPSC-NSCs. Our results showed hiPSC-Neurons and hiPSC-MGLs were more sensitive to H2O2 than hiPSC-NSCs, which indicated the different response styles of hiPSC-NSCs, hiPSC-Neurons, and hiPSC-MGLs to oxidative stress. HiPSC-derived neural cells from AD patients suffered more severe injury from H2O2 than those of CNCs and young subjects, indicating that the vulnerability to oxidative stress of AD patients can be recapitulated in hiPSCs.

The preparation of a novel Au6 cluster bearing a bidentate mixed carbene–thiolate ligand is presented. The length of linker between the central benzimidazole and thiolate has a strong effect on the formation of cluster products, with a C2 chain giving an Au6 cluster, while a C3 chain results in no evidence of cluster formation. Density functional theory analysis predicts a non-metallic cluster with a large HOMO–LUMO (3.2–3.6 eV) and optical gap.

Lycium barbarum is widely used as a functional food and medicinal herb to promote health and longevity in China and in some other Asian countries. In modern pharmacological and chemical studies, the most valuable and well-researched component of L. barbarum is a group of unique water-soluble glycoconjugates that are collectively termed Lycium barbarum polysaccharides (LBPs). Numerous modern pharmacological studies have revealed that LBPs possess antiaging, antidiabetic, antifibrotic, neuroprotective, and immunomodulation properties, while the immunomodulatory effect is primary and is involved in other activities. However, due to their structural heterogeneity and lack of chromophores, it has long been unclear how LBPs work on the immune system. A few studies have recently provided some insights into the proposed mode of action of LBPs, such as structure-activity relationships, receptor recognition, and gut microbiota modulation of LBPs. This review provides a comprehensive overview of the immunoregulating properties of LBPs and their related mechanisms of action.

Oxidative stress, DNA damage repair, and inflammation are three important reactions of sulfur mustard (SM) exposure. But molecular related chronological events in the earlier stage of SM exposure model are still unclear. In the research, reactive oxygen species (ROS) was measured by using flow cytometry. Cytokines were tested in Luminex method. Myeloperoxidase (MPO), inducible nitric oxide synthase (iNOS), 8-hydroxy-2-deoxyguanosine (8-OHdG) and glutathione (GSH) activity or levels in serum were determined by commercially available kits. Western blot was used to determination of phosphorylated histone 2A.X (γ-H2A.X). Results showed that the oxidative stress biomarker of ROS and 8-OHdG were significantly increased early at 0.5h of SM exposure, but GSH level was decreased at 0.5h. Similarly, SM increased γ-H2A.X level early at 2h, which reached to peak at 8h and recovered to normal at 24h. MPO and iNOS activity were also increased early at 2h and 0.5h respectively. However, all selected inflammation biomarkers, including IL-6, TNF-α, IL-1β, MCP-1, GM-CSF and IL-10 concentrations are all unchangeable in 2h. The results indicated that oxidative stress and DNA damage had happened more quickly than inflammation reaction. These chronological events may be due to uncovered generation of reactive oxygen species, DNA alkylation and oxidative DNA damage. In conclusion, this research showed that both oxidative stress and DNA damage are earlier events than inflammation in sulfur mustard toxic mouse model.

Mounting evidence points to alterations in the gut microbiota-neuroendocrine immunomodulation (NIM) network that might drive Alzheimer's Disease (AD) pathology. In previous studies, we found that Liuwei Dihuang decoction (LW) had beneficial effects on the cognitive impairments and gastrointestinal microbiota dysbiosis in an AD mouse model. In particular, CA-30 is an oligosaccharide fraction derived from LW. We sought to determine the effects of CA-30 on the composition and function of the intestinal microbiome in the senescence-accelerated mouse prone 8 (SAMP8) mouse strain, an AD mouse model. Treatment with CA-30 delayed aging processes, ameliorated cognition in SAMP8 mice. Moreover, CA-30 ameliorated abnormal NIM network in SAMP8 mice. In addition, we found that CA-30 mainly altered the abundance of four genera and 10 newborn genera. Advantageous changes in carbohydrate-active enzymes of SAMP8 mice following CA-30 treatment, especially GH85, were also noted. We further found that seven genera were significantly correlated with the NIM network and cognitive performance. CA-30 influenced the relative abundance of these intestinal microbiomes in SAMP8 mice and restored them to SAMR1 mouse levels. CA-30 ameliorated the intestinal microbiome, rebalanced the NIM network, improved the AD-like cognitive impairments in SAMP8 mice, and can thus be a potential therapeutic agent for AD.

Toll-like receptor (TLR) 4 is an important polysaccharide receptor; however, the relationships between the structures and biological activities of TLR4 and polysaccharides remain unknown. Many recent findings have revealed the primary structure of TLR4/MD-2-related polysaccharides, and several three-dimensional structure models of polysaccharide-binding proteins have been reported; and these models provide insights into the mechanisms through which polysaccharides interact with TLR4. In this review, we first discuss the origins of polysaccharides related to TLR4, including polysaccharides from higher plants, fungi, bacteria, algae, and animals. We then briefly describe the glucosidic bond types of TLR4-related heteroglycans and homoglycans and describe the typical molecular weights of TLR4-related polysaccharides. The primary structures and activity relationships of polysaccharides with TLR4/MD-2 are also discussed. Finally, based on the existing interaction models of LPS with TLR4/MD-2 and linear polysaccharides with proteins, we provide insights into the possible interaction models of polysaccharide ligands with TLR4/MD-2. To our knowledge, this review is the first to summarize the primary structures and activity relationships of TLR4-related polysaccharides and the possible mechanisms of interaction for TLR4 and TLR4-related polysaccharides.

AEOL-10150 is a broad-spectrum metalloporphyrin superoxidase dismutase (SOD) mimic specifically designed to neutralize reactive oxygen and nitrogen species. Research has shown that AEOL-10150 is a potent medical countermeasure against national security threats including sulfur mustard (SM), nerve agent exposure and radiation pneumonitis following a radiological/nuclear incident sufficient to cause acute radiation syndrome (ARS). AEOL-10150 performed well in animal safety studies, and two completed phase 1 safety studies in patients demonstrated that the drug was safe and well tolerated, indicating that AEOL-10150 has potential as a new catalytic antioxidant drug. In this article, we review improvements in AEOL-10150 in preclinical pharmacodynamic studies, especially regarding anti-SM, chlorine gas and radiation exposure studies.

To investigate specific changes in metabolites and proteins of Kidney-Yin Deficiency Syndrome (KYDS) patients with diabetes mellitus (DM) in China. KYDS (n=29) and non-KYDS (n=23) patients with DM were recruited for this study. The KYDS was diagnosed by two senior TCM clinicians separately. The metabonomic and proteomic profiles of the patients were assessed using a metabonomic strategy based on NMR with multivariate analysis and a proteomic strategy based on MALDI-TOF-MS, respectively. Eighteen upregulated peptides and thirty downregulated peptides were observed in the plasma of the KYDS patients. Comparing the proteomic profiles of the KYDS and non-KYDS groups, however, no significantly differentially expressed peptides were found. At the same time, major metabolic alterations were found to distinguish the two groups, including eight significantly changed metabolites (creatinine, citrate, TMAO, phenylalanine, tyrosine, alanine, glycine and taurine). The levels of creatinine, citrate, TMAO, phenylalanine and tyrosine were decreased, whereas the levels of alanine, glycine and taurine were increased in the KYDS patients. These biochemical changes were found to be associated with alterations in amino acid metabolism, energy metabolism and gut microflora. The identification of distinct expression profiles of metabolites and signaling pathways in KYDS patients with DM suggests that there are indeed molecular signatures underlying the principles of 'Syndrome Differentiation' in traditional Chinese medicine.

Electrochemical detection of Pam3CSK4, a synthetic triacylated lipopeptide that mimics the structural moieties of its natural Gram negative bacterial pathogen-associated molecular pattern (PAMP) counterpart, has been achieved using hybridized toll-like receptors (TLR) combining TLR1 and TLR2 onto a single sensor surface. These sensors represent the first hybridized TLR sensors. The limit of detection for Pam3CSK4 attained was 7.5 μg/mL, which is within the same order of magnitude for that of the more labor-intensive and time-consuming cell-assay technique, 2.0 μg/mL. The results gathered in these electrochemical experiments show that sensors fabricated by immobilizing a mixture of cooperative TLR1 and -2 generate higher responses when exposed to the analyte in comparison to the control sensors fabricated using pure TLR1 or -2 standalone. A PAMP selectivity test was carried out in line with our inspiration from the mammalian innate immune response. TLRs1-5 as standalone biorecognition elements and the hybridized "TLR1 and 2" sensor surface were investigated, understanding the known TLR-PAMP interactions, through the exploitation of this electrochemical sensor fabrication technique. The experimental result is consistent with observations from previously published in vivo and in vitro studies, and it is the first demonstration of the simultaneous evaluation of electrochemical responses from multiple, unique fabricated TLR sensor surfaces against the same analyte.

It is well known that GnRH analogs can self-assemble into amyloid fibrils and that the duration of action of GnRH analogs depends on the ability of the amyloid to slowly release active peptides. The aim of this study was to investigate the influence of the amino acid residues at position 7 of GnRH analogues on peptide self-assembly. It was found that the dominant shape of the nanostructure can be changed when the structures of the residues at position 7 differ significantly from that of leucine in Degarelix. When the backbone length was extended (peptide 9), or the side chain of the residue at position 7 was replaced by an aromatic ring (peptide 6), or the rotation of the amide bond was restricted (peptide 8), the nanostructure changed from fibrils to vesicles. The results also indicate that the increasing hydrophilicity had little influence on the nanostructure morphology. In addition, a suitable release rate was found to play a more important role for the duration of the peptide action by maintaining the equilibrium between the drug concentration and the persistent release time, while the nanostructure shape was found to exert little influence on the duration of the peptide action. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.

A series of poly(ADP-ribose)polymerase (PARP)-1 inhibitors containing a novel scaffold, the 1H-thieno[3,4-d]imidazole-4-carboxamide moiety, was designed and synthesized. These efforts provided some compounds with relatively good PARP-1 inhibitory activity, and among them, 16l was the most potent one. Cellular evaluations indicated that the anti-proliferative activities of 16g, 16i, 16j and 16l against BRCA-deficient cell lines were similar to that of olaparib, while the cytotoxicities of 16j and 16l toward human normal cells were lower. In addition, ADMET prediction results indicated that these compounds might possess more favorable toxicity and pharmacokinetic properties. This study provides a basis for our further investigation.

(2)-Epigallocatechin-3-gallate (EGCG) is a major polyphenolic component of green tea. A number of studies have demonstrated EGCG has the possibility for delaying the onset or retarding the progression of Alzheimer’s disease (AD) and indicated EGCG possess inhibition of β-secretase activity. We utilized homogeneous time-resolved fluorescence assay with a substrate Eu-CEVNLDAEFK-Qsy7 to screen β-secretase inhibitor in a cell-free system and AlphaLISA assay in cell system. The results first showed that EGCG had significant inhibition of β-secretase activity with IC 50 value of 7.57 × 10 −7 M in screening assay, but then we found EGCG had significant fluorescence-quenching effect in confirming assay, this indicates EGCG has the false positive β-secretase inhibitory activity. Furthermore, the followed AlphaLISA assay based on cell showed EGCG did not reduce the β-amyloid 1–40 secretion in HuAPPswe/HuBACE1 Chinese hamster ovary cell without affecting cell viability. Therefore our findings indicate EGCG do not inhibit β-secretase cleavage activity. Overall this study illustrates that EGCG is not a β-secretase inhibitor based on the compelling data. This provides further support that the choice of complementary assay format or technology is a critical factor in molecular screening and drug development for improving the hit-finding capability and efficiency.

PEGylation is an effective way to improve the pharmacokinetic profiles of pharmaceutical proteins or peptides. But the relatively large and long PEG chains would be likely to shelter the active site of a small peptide because of its small size, compared with a protein. Therefore, the positions and numbers of PEGylation are crucial for the bioactivity of a PEGylated peptide. To elucidate the relationship between the PEGylated positions and bioactivity of a peptide drug, site-specific PEGylations were performed on Zadaxin (Thymosin α 1, Tα1), which is a pharmaceutical peptide with an α-helix region, a β-turn region, and random coils. Site-specific mono-PEGylations of Tα1 in different conformational regions were realized through introducing one cysteine residue into the desired positions of the peptide, followed by a coupling reaction with a thiol-attached maleimide-PEG reagent. Primary data from IFN-γ production of splenocytes induced by Con A showed that the influence of PEGylation on Zadaxin was position-dependent, and mostly, positive effects were observed after PEGylation, which indicated that the position of PEGylation is important for maintaining the bioactivity of a peptide.

Hemiasterlin is a tripeptide with highly alkylated unnatural amino acids. It acts as a potent tumor cell growth inhibitor. From the comparison of the N-terminal between hemiasterlin and its analogues, a further modification was conducted on this position for a SAR study. Some unnatural amino acids with aryl or ureido groups were introduced into the N-terminal of hemiasterlin analogues to improve their hydrophobicity/hydrophilicity. Here 14 hemiasterlin analogues were synthesized. And their activities against tumor cell lines were evaluated. Discussions on SAR preliminarily indicated that no matter whether the N-terminals come from the aryl or alkyl units, sufficient steric bulk, lipophilicity and methylation of the N-terminal should be crucial factors to the cytotoxic activity.

Widespread pharmacology research has revealed that immune regulation is the main biological effect of Lycium barbarum, and the material bases to elicit the effect of L. barbarum on the immune system are polysaccharide and glycoprotein complexes. Studies have found that the effect of L. barbarum polysaccharide on the activation of macrophages and dendritic cells are important in participating in the immune response. In addition, it was found that TLR4/2 may be closely related to the immunoregulatory activity of L. barbarum polysaccharide. Further, the TLR4/2-activated signaling pathways lead to activation of phosphoinositide-3-kinase (PI3K) and LKB1, leading to activation of the mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK) and nuclear factor-κB (NF-κB), p53, C-Jun and AP-1. These pathways lead to induction of gene transcription. L. barbarum can induce production of a variety of cytokines, such as the anti-inflammatory factor IL-10, proinflammatory cytokines IL-1s and IL-6, chemokines IL-8, antitumor factors cytokine TNF-ɑ, antiviral factor IFN-γ, TGF-s1, and lymphocyte activators IL-2 and IL-4. L. barbarum polysaccharide could also upregulate CD40, CD80, CD86, and major histocompatibility complex (MHC) class II molecules to various extents, and enhance antibody titers. Ultimately, activation of these transcription pathways induces expression of pro-inflammatory cytokines and immune regulation, survival, and proliferation.

A series of novel quinoline-3-carboxamide derivatives were synthesized and evaluated for their immunomodulatory activity. The compounds were tested in vitro for effects on spleen lymphocyte proliferation and TNF-α production by macrophage. Three compounds showed immunomodulatory profiles similar to and more potent than those of linomide and FR137316 and were selected for further pharmacological studies in vivo.

We have developed a series of substituted 4-(thiophen-2-ylmethyl)-2H-phthalazin-1-ones as potent PARP-1 inhibitors. Preliminary biological evaluation indicated that most compounds possessed inhibitory potencies comparable to, or higher than AZD-2281. Among these compounds, 18q appeared to be the most notable one, which displayed an 8-fold improvement in enzymatic activity compared to AZD-2281. These efforts lay the foundation for our further investigation.

Mitral valvular disease is strongly related to atrial fibrillation (AF), but the different types of mitral valvular disease have a different prevalence of AF. In this study we explored the expressions of the circulating and local renin-angiotensin-aldosterone system (RAAS) in order to determine the relationship between circulating and local RAAS expressions and its effects on AF in different types of mitral valvular disease patients. Our study group consisted of 24 mitral valvular disease patients scheduled for mitral valve replacement surgery. Peripheral blood samples and left atrial appendage tissue samples were obtained from all patients. Radioimmunoassay was performed to assess the expression levels of circulating and local renin, angiotensin II and aldosterone. In mitral valvular diseases, linear correlation analyses were done for local and circulating renin, angiotensin II and aldosterone; the p values were 0.979, 0.518 and 0.125, respectively. Expression levels of local angiotensin II, circulating angiotensin II and local aldosterone were significantly increased in the AF group compared with sinus rhythm; the p values were 0.023, 0.042 and 0.035, respectively. In mitral stenosis patients, AF was primarily associated with local angiotensin II ( p =0.010), as well as being associated with circulating angiotensin II ( p =0.038). In mitral regurgitation patients, AF was only significantly associated with local angiotensin II ( p =0.038). Circulating and local RAAS expressions are associated with AF in mitral valvular disease patients. The levels of circulating and local RAAS expressions were different in AF patients with different types of mitral valvular diseases. The differentiation of circulating and local RAAS expression levels in AF patients between different types of mitral valvular disease can potentially improve the specific pharmacological interventions outcomes for these patients.

A simple and efficient procedure for the fluorescent labeling of saccharides is a prerequisite step for imaging the transport of polysaccharides in living cells. We report a one-pot strategy for the fluorescent labeling of saccharides with fluorescein-5-thiosemicarbazide (FTSC), which introduces the thiosemicarbazide group of FTSC to the aldehyde group at the reducing end of saccharides to form stable amino derivatives via reductive amination. The Glc-FTSC derivative was characterized by HPLC-MS, HRESIMS and NMR spectroscopy. Saccharides were quantitatively labeled with FTSC at 75°C for 1 h under optimum reaction conditions. Fluorescence studies illustrated that the conjugation of FTSC to saccharides did not change its florescence properties (λ(ex)=495 nm, λ(em)=517 nm), presenting desirable compatibility with commonly used fluorescence equipment. Polysaccharide AAG-FTSC derivatives exhibited rather low levels of cytotoxicity against rat thymus cells, and the fluorescent labeling procedure had slight impact on their anti-tumor activity. Results indicate that the assay neither introduces discernible cytotoxicity against living cells nor obviously alters the functional activities of polysaccharides, and provides a convenient, highly efficient fluorescent labeling approach for imaging the transport of polysaccharides in living cells.

Results and Discussion According to the SAR results [1], the conjugating sites of Tα1 with PEG were chosen at the N-terminus, C-terminus, α-helix, β-turn, and the random coil regions. Referring to the method reported by Vanwetsswinkel et al [2,3], [Cys]Tα1 analogs (x: the chosen site) were synthesized firstly for conveniently introducing the covalent attachment mPEG-MAL into the chosen sites, and then the PEG conjugations were prepared as follows (Scheme 1) .

Site-specific mono-PEGylations were performed in different conformational regions of Thymosin alpha 1 (T alpha 1) by introducing one cysteine residue into the chosen site and coupling with thiol-specific mPEG-MAL reagent. Results demonstrated that PEGylated sites and regions influenced the conformations and pharmacokinetic profiles of the peptide greatly with following order: alpha-helix, beta-turn, random coil and terminals, but little on the immunoactivity.

In this work, metabonomic methods utilizing (1)H NMR spectroscopy and multivariate statistical technique have been applied to investigate the metabolic profiles of SAM. The serum metabolome of senescence-prone 8 (SAMP8), a murine model of age-related learning and memory deficits and Alzheimer's disease (AD), was compared with that of control, senescence-resistant 1 (SAMR1), which shows normal aging process. Serum samples were collected for study from both male and female 12-month-old SAMP8 and age matched SAMR1 ( n = 5). (1)H NMR spectra of serum were analyzed by pattern recognition using principal components analysis. The results showed that the serum metabolic patterns of SAMP8 and SAMR1 were significantly different due to strains and genders. Subtle differences in the endogenous metabolite profiles in serum between SAMP8 and SAMR1 were observed. The most important metabolite responsible for the strain separation was lack of inosine, which meant the protective function of anti-inflammation, immunomodulation and neuroprotection might be attenuated in SAMP8. Other differential metabolites observed between strains included decreased glucose, PUFA, choline, phosphocholine, HDL, LDL, D-3-hydoxybutyrate, citrate and pyruvate and increased lactate, SFA, alanine, methionine, glutamine and VLDL in serum of SAMP8 compared with those of SAMR1, suggesting perturbed glucose and lipid metabolisms in SAMP8. Besides the differences observed between the strains, an impact of gender on metabolism was also found. The females exhibited larger metabolic deviations than males and these gender differences in SAMP8 were much larger than in SAMR1. Higher levels of VLDL, lactate and amino acids and lower levels of HDL, LDL and unsaturated lipids were detected in female than in male SAMP8. These facts indicated that the metabolism disequilibrium in female and male SAMP8 was different and this may partly explain that females were more prone to AD than males. The results of this work may provide valuable clues to the understanding of the mechanisms of the senile impairment and the pathological changes of AD, as well as show the potential power of the combination of the NMR technique and the pattern recognition method for the analysis of the biochemical changes of certain pathophysiologic conditions.

Roquinimex is an immunomodulator that can effectively inhibit the development of several autoimmune diseases in animal models, but the mechanism is still unknown. In this study, we investigated the effect of roquinimex on chronic graft-versus-host disease (GVHD) in mice, a well-established model for human systemic lupus erythematosus (SLE). Oral administration of roquinimex significantly suppressed the development of proteinuria and ameliorated nephritis symptoms in chronic GVHD mice. In addition, renal histopathology and immunohistochemistry studies revealed reduced glomerulonephritis and decreased IgG deposition in chronic GVHD mice treated with roquinimex. Chronic GVHD is characterized by a predominance of Th2 cytokines, and proinflammatory cytokines that also play an important role in the pathology of tissue damage. Therefore, we focused on the effect of roquinimex on cytokine production. Chronic GVHD mouse splenocytes exhibited severely reduced interferon (IFN)-gamma production in response to Concanavalin (Con A) stimulation and an overt Th2 skewness. Roquinimex treatment, however, induced IFN-gamma production and restored the Th1/Th2 cytokine balance, although only a minimal effect of roquinimex on interleukin (IL)-4 secretion was observed. The production of the proinflammatory cytokines TNF-alpha and IL-1 beta by peritoneal macrophages from lipopolysaccharide (LPS)-treated GVHD mice was significantly inhibited by roquinimex treatment. These data suggested that the beneficial effect of roquinimex on lupus might, at least in part, result from a restoration of Th1/Th2 cytokine balance and inhibition of inflammatory cytokine production.

A series of novel quinoline-3-carboxamide derivatives were synthesized and evaluated for their immunomodulatory activity. The compounds were tested in vitro for effects on spleen lymphocyte proliferation and TNF-α production by macrophage. Three compounds showed immunomodulatory profiles similar to and more potent than those of linomide and FR137316 and were selected for further pharmacological studies in vivo.

In a previous study, systemic administration of the GABA(B) receptor agonist, R-(+)-baclofen (2.5 mg/kg, i.p.) blocked acute amphetamine (2.5 mg/kg, i.p.)-induced rearing and neuropeptide (preprodynorphin (PPD), preprotachykinin (PPT), preproenkephalin (PPE), and secretogranin II (SGII)) mRNA expression in the striatum (Zhou et al, 2004). The purpose of the present study was to investigate the site(s) of action of these baclofen effects in the dorsal and ventral striatal circuitries. Infusion of baclofen (75 ng/side) into the ventral tegmental area (VTA), substantia nigra (SN), nucleus accumbens (NA), caudate-putamen (Cpu), or medial prefrontal cortex (mPFC) had no effect on behavioral activity in saline-treated rats habituated to a photocell apparatus. However, intra-VTA infusion of baclofen (75 ng/side) completely blocked, whereas intra-NA and intra-SN infusion of baclofen attenuated, amphetamine-induced vertical activity without affecting amphetamine-induced total distance traveled. In contrast, intramedial PFC and intra-CPu infusion of baclofen had no effect on behavioral activity in amphetamine-treated rats. Infusion of baclofen into the VTA, NA, or SN decreased amphetamine-induced neuropeptide gene expression in the striatum. These results indicate that GABA(B) receptor stimulation within the ventral striatal circuitry is involved in mediating acute amphetamine-induced behaviors and neuropeptide gene expression in the dorsal and ventral striatum. The present study provides information on the potential targets in the brain for baclofen in the initial behavioral and genomic response to amphetamine.

The purpose of this study was to investigate whether GABAB receptor activation blocks acute amphetamine-induced behavioral activity, dopamine release, and neuropeptide mRNA expression in the striatum. Systemic administration of R-(+)-baclofen (1.25 mg/kg, i.p.) did not alter total distance traveled or vertical rearing induced by amphetamine (2.5 mg/kg, i.p.). At 2.5 mg/kg, baclofen did not alter spontaneous motor activity or total distance traveled, but completely blocked vertical rearing induced by amphetamine. At 5.0 mg/kg, baclofen completely blocked both total distance traveled and vertical rearing induced by amphetamine. Quantitative in situ hybridization histochemistry revealed that baclofen (2.5 mg/kg, i.p.) decreased the ability of amphetamine to increase preprodynorphin (PPD), preprotachykinin (PPT), preproenkephalin (PPE), and secretogranin II (SGII) mRNA levels in the striatum without altering the basal levels of these signals. Baclofen also blocked the amphetamine-induced rise in SGII mRNA in the core and shell of the nucleus accumbens and cingulate cortex. In a separate experiment, systemic baclofen (2.5 mg/kg) decreased the amphetamine-induced increase in dialysate dopamine levels in the striatum. These results suggest that reduced striatal dopamine release contributes to the ability of GABAB receptor activation to decrease acute amphetamine-induced behavioral activity and striatal neuropeptide gene expression.

The effects in the brain of selective estrogen receptor modulators (SERMs) such as tamoxifen and raloxifene have not yet been fully elucidated. Based upon the hypothesis that serotonin (5-HT)-steroid hormone interactions are important in mood regulation, we have compared six SERMs (tamoxifen, raloxifene, levormeloxifene, NNC 45-0781, NNC 45-0320, NNC 45-1506) with 17β-estradiol (E2) in terms of their ability to regulate mRNA levels of estrogen receptor (ER)α, ERβ, 5-HT1A receptor, and 5-HT reuptake transporter (SERT) in the midbrain, amygdala, and hypothalamus of ovariectomized (OVX) rats. Female rats (n = 6/group, 8 groups total) were OVX and allowed to recover for 2 weeks. During the third post-OVX week, rats were injected subcutaneously with E2 (0.1 mg/kg) or one of the SERMs (5 mg/kg) once per day for 7 days. Twenty-four hours after the last injection, tissue was collected for the determination of mRNA levels by ribonuclease protection assay (RPA). E2 treatment significantly decreased mRNA levels for ERα, ERβ, and SERT in midbrain and ERα in hypothalamus. Tamoxifen increased ERβ mRNA levels in hypothalamus, while raloxifene increased ERβ mRNA levels in amygdala. NNC 45-0320 decreased ERα mRNA in hypothalamus and decreased ERβ mRNA in amygdala. These results suggest that while SERMs are not full estrogen receptor agonists in the brain, the agonist/antagonist profiles for individual SERMs may differ among brain areas. This raises the possibility of developing new SERMs for selective functions in specific brain areas.