Electroacupuncture improves repeated social defeat stress-elicited social avoidance and anxiety-like behaviors by reducing Lipocalin-2 in the hippocampus.

BACKGROUND: Post-traumatic stress disorder (PTSD) is a trauma-related disorder that is associated with pro-inflammatory activation and neurobiological impairments in the brain and leads to a series of affective-like behaviors. Electroacupuncture (EA) has been proposed as a clinically useful therapy for several brain diseases. However, the potential role of EA treatment in PTSD and its molecular and cellular mechanisms has rarely been investigated. METHODS: We used an established preclinical social defeat stress mouse model to study whether EA treatment modulates PTSD-like symptoms and understand its underlying mechanisms. To this end, male C57BL/6 mice were subjected to repeated social defeat stress (RSDS) for 6 consecutive days to induce symptoms of PTSD and treated with EA at Baihui (GV 20) and Dazhui (GV 14) acupoints. RESULTS: The stimulation of EA, but not needle insertion at Baihui (GV 20) and Dazhui (GV 14) acupoints effectively improved PTSD-like behaviors such as, social avoidance and anxiety-like behaviors. However, EA stimulation at the bilateral Tianzong (SI11) acupoints did not affect the PTSD-like behaviors obtained by RSDS. EA stimulation also markedly inhibited astrocyte activation in both the dorsal and ventral hippocampi of RSDS-treated mice. Using next-generation sequencing analysis, our results showed that EA stimulation attenuated RSDS-enhanced lipocalin 2 expression in the hippocampus. Importantly, using double-staining immunofluorescence, we observed that the increased lipocalin 2 expression in astrocytes by RSDS was also reduced by EA stimulation. In addition, intracerebroventricular injection of mouse recombinant lipocalin 2 protein in the lateral ventricles provoked social avoidance, anxiety-like behaviors, and the activation of astrocytes in the hippocampus. Interestingly, the overexpression of lipocalin 2 in the brain also altered the expression of stress-related genes, including monoamine oxidase A, monoamine oxidase B, mineralocorticoid receptor, and glucocorticoid receptor in the hippocampus. CONCLUSIONS: This study suggests that the treatment of EA at Baihui (GV 20) and Dazhui (GV 14) acupoints improves RSDS-induced social avoidance, anxiety-like behaviors, astrocyte activation, and lipocalin 2 expression. Furthermore, our findings also indicate that lipocalin 2 expression in the brain may be an important biomarker for the development of PTSD-related symptoms.

Sex-dependent monoamine oxidase isoforms expression patterns during human brain ageing.

Human behavior is influenced by both genetic and environmental factors. Monoamine oxidase A (MAOA) is among the most investigated genetic determinants of violent behaviors, while the monoamine oxidase B (MAOB) is explored in Parkinson's disease. We collected twenty-four post-mortem brain tissue datasets of 3871 and 1820 non-demented males and females, respectively, who died from causes not attributable to neurodegenerative diseases. The gene expressions of MAOA and MAOB (MAO genes) were analyzed in these subjects, who were further stratified according to age into eleven groups ranging from late Infancy (5-9 months) to centenarians (>100 years). MAO genes were differently expressed in brains during the entire life span. In particular, maximal and minimal expression levels were found in early life and around the teen years. Females tended to have higher MAO gene levels throughout their lives than those found in age-matched males, even when expressions were separately measured in different brain regions. We demonstrated the existence of age- and sex- related variations in the MAO transcript levels in defined brain regions. More in-depth protein studies are needed to confirm our preliminary results obtained only on messenger RNAs in order to establish the role played by MAO genes in human development.

Bidirectional Cross-talk between MAOA and AR Promotes Hormone-Dependent and Castration-Resistant Prostate Cancer.

Androgen receptor (AR) is the primary oncogenic driver of prostate cancer, including aggressive castration-resistant prostate cancer (CRPC). The molecular mechanisms controlling AR activation in general and AR reactivation in CRPC remain elusive. Here we report that monoamine oxidase A (MAOA), a mitochondrial enzyme that degrades monoamine neurotransmitters and dietary amines, reciprocally interacts with AR in prostate cancer. MAOA was induced by androgens through direct AR binding to a novel intronic androgen response element of the MAOA gene, which in turn promoted AR transcriptional activity via upregulation of Shh/Gli-YAP1 signaling to enhance nuclear YAP1-AR interactions. Silencing MAOA suppressed AR-mediated prostate cancer development and growth, including CRPC, in mice. MAOA expression was elevated and positively associated with AR and YAP1 in human CRPC. Finally, genetic or pharmacologic targeting of MAOA enhanced the growth-inhibition efficacy of enzalutamide, darolutamide, and apalutamide in both androgen-dependent and CRPC cells. Collectively, these findings identify and characterize an MAOA-AR reciprocal regulatory circuit with coamplified effects in prostate cancer. Moreover, they suggest that cotargeting this complex may be a viable therapeutic strategy to treat prostate cancer and CRPC. SIGNIFICANCE: MAOA and AR comprise a positive feedback loop in androgen-dependent and CRPC, providing a mechanistic rationale for combining MAOA inhibition with AR-targeted therapies for prostate cancer treatment.

Cerebral MAO Activity Is Not Altered by a Novel Herbal Antidepressant Treatment.

Inhibition of monoamine oxidase (MAO)-A/B can ameliorate depressive- and anxiety-related symptoms via increase of monoamine extracellular levels. However, such inhibition can also instigate hypertensive response following exposure to dietary tyramine (i.e., "the cheese effect"). Novel herbal treatment (NHT) is an herbal formula that has been demonstrated to reduce depressive- and anxiety-like symptoms in pre-clinical studies. The aim of the current study was to examine whether the therapeutic potential of NHT is underlain by inhibition of MAO-A/B and whether NHT poses a risk for tyramine hyper-potentiation. Unpredictable chronic mild stress (UCMS)-exposed mice and naïve mice were treated for 3 weeks with NHT (30 mg/kg; i.p.), the selective serotonin reuptake inhibitor (SSRI) escitalopram (15 mg/kg; i.p.), or saline. Subsequently, MAO-A/B activities in the hypothalamus, striatum, and prefrontal cortex (PFC) were assessed. Exposure to UCMS led to significant increases in both MAO-A and MAO-B activities in the hypothalamus (p < 0.001) and in the PFC (p < 0.01 for MAO-A; p < 0.001 for MAO-B). Neither NHT nor escitalopram had any notable effects. Treatment with NHT was supported as safe in terms of risk for inducing a hypertensive response. The antidepressant- and anxiolytic-like effects of NHT are mediated via pathways other than MAO-A/B inhibition.

Vitamin D improves vascular function and decreases monoamine oxidase A expression in experimental diabetes.

The active form of vitamin D, 1,25-dihydroxycholecalciferol (1,25(OH)2D3), was reported to improve vascular function in patients with diabetes, yet the underlying mechanisms remain to be fully elucidated. Monoamine oxidase (MAO), a mitochondrial enzyme, with two isoforms (A and B) that generates hydrogen peroxide (H2O2) as by-product, has been recently reported to contribute to the pathogenesis of endothelial dysfunction in diabetes. The present study assessed the interaction between vitamin D and MAO in the vascular wall in the setting of type 1 experimental diabetes. To this aim, diabetes was induced in male Wistar rats via a single injection of streptozotocin (STZ, 50 mg/kg, IP) and 1 month later thoracic aortas were harvested and used for organ bath studies and H2O2 measurements. MAO expression was assessed by immunohistochemistry and RT-PCR. Endothelial function was evaluated in isolated aortic rings in the absence vs. presence of 1,25(OH)2D3 (100 nM, 24 h incubation). In diabetic animals, we found a significant reduction in the endothelial-dependent relaxation to acetylcholine and an increased expression of the MAO-A isoform, respectively. Vitamin D significantly improved vascular function, mitigated oxidative stress and decreased MAO-A expression in diabetic vascular preparations. In conclusion, MAO-A is induced in diabetic aortas and vitamin D can improve diabetes-induced endothelial dysfunction by modulating the MAO-A expression.

Moringa oleifera extract attenuates the CoCl2 induced hypoxia of rat's brain: Expression pattern of HIF-1α, NF-kB, MAO and EPO.

Hypoxia-induced oxidative stress and apoptosis are the major hallmark explanations underlying brain dysfunction. Hypoxia in the current study was induced by Cobalt chloride (CoCl2) treatment in rats. The aim of this experiment was to explore the potential ameliorative potency of Moringa oleifera ethanolic extract (MO) against experimentally induced hypoxia on the structure and function of the rat's brain. Fifty male rats were allocated to five groups (10 rats each): a control group, a MO-treated group (400 mg/kg bw, orally), a CoCl2-treated group (40 mg/kg bw/day, orally), a prophylaxis group, and a therapeutic co-treated group. Oxidative stress biomarkers and monoamine neurotransmitter were evaluated in brain tissue. In addition, qRT-PCR for expression pattern of HIF-1α, EPO, CYTO, NF-kB, and MAO-A. Glial fibrillary acidic protein (GFAP), apoptotic markers (BCL-2 and caspase 3) were detected immunohistochemically in brain cells. The results revealed a significantly lower concentration of GABA, monoamine neurotransmitter in hypoxic rat's brain. Moreover, an evident up-regulation of the mRNA expression of HIF-1α, EPO, CYTO, NF-kB, and MAO-A. There was marked encephalopathy manifested by pyknotic neurons with eosinophilic cytoplasm, vacuolations and cerebral congestions in the hypoxic rat brains. Additionally, the score of neuronal expression occupied by GFAP- positive astroglia, Caspase-3 and microglial CD68 were elevated but Bcl-2 expression was found decreased in the hypoxic group than control. The endpoints of this study clearly stated that MO ethanolic extract suggestively counteracted neurotoxic impacts caused by hypoxia, particularly when it administered prior to and concurrently with CoCl2 administration.

Site-specific expression of amine oxidases in breast cancer metastases.

We aimed to evaluate the expression of amine oxidase-related proteins in metastatic breast cancer tissue and determine its clinical implication. A tissue microarray was constructed from a total of 126 metastatic breast tumors (31 bone metastases (24.6%), 36 brain metastases (28.6%), 11 liver metastases (8.7%), and 48 lung metastases (38.1%)). Immunohistochemical staining for amine oxidase-related proteins (lysyl oxidase, diamine oxidase, and monoamine oxidase A and B) was performed. In metastatic breast cancer tissue, lysyl oxidase ( p = 0.001), tumoral diamine oxidase ( p = 0.003), stromal diamine oxidase ( p = 0.047), and stromal monoamine oxidase B ( p = 0.002) were differentially expressed in different metastatic sites. Bone metastases showed low expression of lysyl oxidase, tumoral diamine oxidase, and stromal diamine oxidase. We observed high expression of lysyl oxidase in brain metastases, tumoral diamine oxidase in liver metastases, stromal diamine oxidase in lung metastases, and stromal monoamine oxidase B in bone metastases. Lysyl oxidase positivity was associated with progesterone receptor negativity ( p = 0.001), and monoamine oxidase A positivity was associated with human epidermal growth factor receptor-2 negativity ( p = 0.003) and the luminal A subtype ( p = 0.003). On univariate analysis shorter overall survival was associated with stromal diamine oxidase negativity ( p = 0.008), especially in lung metastases ( p = 0.025), and stromal monoamine oxidase B positivity ( p < 0.001). Stromal monoamine oxidase B positivity was an independent prognostic factor for shorter overall survival in multivariate Cox analysis (hazard ratio, 4.069; 95% confidence interval, 1.649-10.04; p = 0.002). Finally, in metastatic breast cancer, amine oxidase-related proteins were differentially expressed in a manner specific to metastatic site, and stromal monoamine oxidase B expression was correlated with prognosis.

Behavioral, Biochemical and Molecular Characterization of a Parkinson's Disease Mouse Model Using the Neurotoxin 2'-CH3-MPTP: A Novel Approach.

The neurotoxin MPTP has long been used to create a mouse model of Parkinson's disease (PD). Indeed, several MPTP analogues have been developed, including 2'-CH3-MPTP, which was shown to induce nigrostriatal DA neuronal depletion more potently than MPTP. However, no study on behavioral and molecular alterations in response to 2'-CH3-MPTP has been carried out so far. In the present work, 2'-CH3-MPTP was administered to mice (2.5, 5.0 and 10 mg/kg per injection, once a day, 5 days) and histological, biochemical, molecular and behavioral alterations were evaluated. We show that, despite a dose-dependent-like pattern observed for nigrostriatal dopaminergic neuronal death and dopamine depletion, dose-specific alterations in dopamine metabolism and in the expression of dopaminergic neurotransmission-associated genes could be related to specific motor deficits elicited by the different doses tested. Interestingly, 2'-CH3-MPTP leads to increased DAT and MAO-B transcription, which could explain, respectively, its higher potency and the requirement of higher doses of MAO inhibitors to prevent nigrostriatal neuronal death when compared to MPTP. Also, perturbations in dopamine metabolism as well as possible alterations in dopamine bioavailability in the synaptic cleft were also identified and correlated with strength and ambulation deficits in response to specific doses. Overall, the present work brings new evidence supporting the distinct effects of 2'-CH3-MPTP when compared to its analogue MPTP. Moreover, our data highlight the utmost importance of a precise experimental design, as different administration regimens and doses yield different biochemical, molecular and behavioral alterations, which can be explored to study specific aspects of PD.

Chronic BMY7378 treatment alters behavioral circadian rhythms.

The mammalian circadian clock is synchronized to the day : night cycle by light. Serotonin modulates the circadian effects of light, with agonists inhibiting response to light and antagonists enhancing responses to light. A special class of serotonergic compounds, the mixed 5-HT1A agonist/antagonists, potentiates light-induced phase advances by up to 400% when administered acutely. In this study, we examine the effects of one of these mixed 5-HT1A agonist/antagonists, BMY7378, when administered chronically. Thirty adult male hamsters were administered either vehicle or BMY7378 via surgically implanted osmotic mini pumps over a period of 28 days. In a light : dark cycle, chronic BMY7378 advanced the phase angle of entrainment, prolonged the duration of the active phase and attenuated the amplitude of the wheel-running rhythm during the early night. In constant darkness, chronic treatment with BMY7378 significantly attenuated light-induced phase advances, but had no significant effect on light-induced phase delays. Non-photic phase shifts to daytime administration of a 5-HT1A/7 agonist were also attenuated by chronic BMY7378 treatment. qRT-PCR analysis revealed that chronic BMY7378 treatment upregulated mRNA for 5-HT1A and 5-HT1B receptors in the hypothalamus and downregulated mRNA for 5-HT1A and monoamine oxidase-A in the brainstem. These results highlight adaptive changes of serotonin receptors in the brain to chronic treatment with BMY7378 and link such up- and downregulation to changes in important circadian parameters. Such long-term changes to the circadian system should be considered when patients are treated chronically with drugs that alter serotonergic function.

Decreased Monoamine Oxidase A Expression and Activity in the Bladders of Rats With Partial Outlet Obstruction.

OBJECTIVE: To investigate changes in expression and activity of monoamine oxidase A (MAO-A) in rats with partial bladder outlet obstruction (pBOO). Previous studies suggested that monoamines, such as serotonin (5-hydroxytryptamine [5-HT]) and noradrenaline, are involved in bladder hyperactivity secondary to pBOO. However, little is known about the role of MAO-A, an enzyme oxidizing 5-hydroxytryptamine and noradrenalin, in the pathogenesis. MATERIALS AND METHODS: Female Sprague Dawley rats were subjected to sham or pBOO operations for 7 days, then their bladders were isolated. MAO-A protein levels in the bladder were examined by Western blotting. MAO-A activity was measured by the commercially available MAO-Glo Assay kit. In addition, MAO-A distribution in the bladder was examined by immunohistochemistry. RESULTS: Weights of the bladders from rats with pBOO were increased about 3.5-fold, compared with those from sham rats. Significant decreases in MAO-A protein and activity levels were observed in whole bladder of rats with pBOO compared with those of sham rats. By immunohistochemistry, it was firstly demonstrated that MAO-A was predominantly expressed in the detrusor layer of the sham rat bladders. The intensity of staining was decreased after pBOO operation. CONCLUSION: We demonstrated, for the first time, the distribution of MAO-A in the bladder and the pathologic changes in MAO-A protein and activity levels in rats with pBOO. This marked decrease in MAO-A potentially resulting in increased monoamine levels, especially in the detrusor of rat bladder, might be a key factor explaining the mechanism of bladder overactivity associated with pBOO.

Melatonin mediated antidepressant-like effect in the hippocampus of chronic stress-induced depression rats: Regulating vesicular monoamine transporter 2 and monoamine oxidase A levels.

The hippocampus is sensitive to stress which activates norepinephrine terminals deriving from the locus coeruleus. Melatonin exerts positive effects on the hippocampal neurogenic process and on depressive-like behaviour. Thus, in the present study, an examination was made of the effect of chronic melatonin treatment on norepinephrine content, synthesis, uptake, vesicular transport and degradation in the hippocampus of rats exposed to CUMS. This entailed quantifying the norephinephrine, mRNA and protein levels of DBH, NET, VMAT 2, MAO-A and COMT. The results show that CUMS evoked prolonged immobility. Melatonin treatment decreased immobility in comparison with the placebo group, reflecting an antidepressant-like effect. Compared with the placebo group, a dramatic decrease in norepinephrine content, decreased VMAT2 mRNA and protein and increased MAO-A protein levels in the hippocampus of the CUMS rats were observed. However, no significant differences in the levels of DBH, NET, COMT mRNA and protein and MAO-A mRNA levels between the placebo and the stressed groups were found. The results showed the restorative effects of melatonin on the stress-induced decline in the norepinephrine content of the hippocampus. It was observed that melatonin treatment in the CUMS rats prevented the stress-induced decrease in VMAT2 mRNA and protein levels, whereas it reduced the increase of the mRNA of COMT and protein levels of MAO-A. Chronic treatment with melatonin failed to alter the gene expression of DBH or NET in the hippocampus of the CUMS rats. Additionally, the results show that melatonin enhances VMAT2 expression and norepinephrine storage, whilst it reduces norepinephrine degrading enzymes.

Amphetamine manipulates monoamine oxidase-A level and behavior using theranostic aptamers of transcription factors AP-1/NF-kB.

BACKGROUND: Monoamine oxidase (MAO) enzymes play a critical role in controlling the catabolism of monoamine neurotransmitters and biogenic trace amines and behavior in humans. However, the mechanisms that regulate MAO are unclear. Several transcription factor proteins are proposed to modulate the transcription of MAO gene, but evidence supporting these hypotheses is controversial. We aimed to investigate the mechanism of gene transcription regulator proteins on amphetamine-induced behavior. We applied aptamers containing a DNA binding sequence, as well as a random sequence (without target) to study the modulation of amphetamine-induced MAO levels and hyperactivity in living mice. METHODS: We pretreated in adult male C57black6 mice (Taconic Farm, Germantown, NY) (n ≥ 3 litters at a time), 2 to 3 months of age (23 ± 2 gm body weight) with double-stranded (ds) DNA aptamers with sequence specific to activator protein-1 (5ECdsAP1), nuclear factor-kappa beta (5ECdsNF-kB), special protein-1 (5ECdsSP-1) or cyclicAMP responsive element binding (5ECdsCreB) protein binding regions, 5ECdsRan [a random sequence without target], single-stranded AP-1 (5ECssAP-1) (8 nmol DNA per kg) or saline (5 µl, intracerebroventricular [icv] injection) control before amphetamine administration (4 mg/kg, i.p.). We then measured and analyzed locomotor activities and the level of MAO-A and MAO-B activity. RESULTS: In the pathological condition of amphetamine exposure, we showed here that pretreatment with 5ECdsAP1 and 5ECdsNF-kB reversed the decrease of MAO-A activity (p < 0.05, t test), but not activity of the B isomer (MAO-B), in the ventral tegmental area (VTA) and substantia nigra (SN) of C57black6 mice. The change in MAO-A level coincided with a reversed amphetamine-induced restless behavior of mice. Pretreatments with saline, 5ECdsCreB, 5ECdsSP-1, 5ECdsRan or 5ECssAP-1 had no effect. CONCLUSION: Our data lead us to conclude that elevation of AP-1 or NF-kB indirectly decreases MAO-A protein levels which, in turn, diminishes MAO-A ability in the VTA of the mesolimbic dopaminergic pathway that has been implicated in cells under stress especially in the SN and VTA. This study has implications for design for the treatment of drug exposure and perhaps Parkinson's dementia.

MAOA expression predicts vulnerability for alcohol use.

The role of the monoamines dopamine (DA) and serotonin (5HT) and the monoamine-metabolizing enzyme monoamine oxidase A (MAOA) have been repeatedly implicated in studies of alcohol use and dependence. Genetic investigations of MAOA have yielded conflicting associations between a common polymorphism (MAOA-LPR) and risk for alcohol abuse. The present study provides direct comparison of tissue-specific MAOA expression and the level of alcohol consumption. We analyzed rhesus macaque MAOA (rhMAOA) expression in blood from males before and after 12 months of alcohol self-administration. In addition, nucleus accumbens core (NAc core) and cerebrospinal fluid (CSF) were collected from alcohol access and control (no alcohol access) subjects at the 12-month time point for comparison. The rhMAOA expression level in the blood of alcohol-naive subjects was negatively correlated with subsequent alcohol consumption level. The mRNA expression was independent of rhMAOA-LPR genotype and global promoter methylation. After 12 months of alcohol use, blood rhMAOA expression had decreased in an alcohol dose-dependent manner. Also after 12 months, rhMAOA expression in the NAc core was significantly lower in the heavy drinkers, as compared with control subjects. The CSF measured higher levels of DA and lower DOPAC/DA ratios among the heavy drinkers at the same time point. These results provide novel evidence that blood MAOA expression predicts alcohol consumption and that heavy alcohol use is linked to low MAOA expression in both the blood and NAc core. Together, the findings suggest a mechanistic link between dampened MAOA expression, elevated DA and alcohol abuse.

Effects of Renin-Angiotensin System Inhibitors on Renal Expression of Renalase in Sprague-Dawley Rats Fed With High Salt Diet.

BACKGROUND/AIMS: The aim of our study was to investigate the effect of high-salt diet on the renal expression of renalase and the potential role of the local renin-angiotensin system in this process. METHODS: Sprague-Dawley (SD) rats were divided into groups according to salt content in diet and drug treatment as follows: normal-salt diet (NS), high-salt diet (HS), high-salt intake with hydralazine (HS+H), high-salt diet with enalapril (HS+E), and high-salt diet with valsartan (HS+V). The dietary intervention and drugs were given for four weeks. Renin activity and angiotensin II type 1 receptor (AT1R) levels were detected by real-time PCR. Renalase mRNA and protein were also measured. RESULTS: After four weeks, systolic blood pressure and proteinuria were significantly increased in the HS group with respect to the NS group. Dietary salt intake caused a dramatic decrease in renalase expression in the rat kidneys. Renal cortex renin and AT1R increased significantly in the HS and HS+H groups. Urinary protein was positively correlated with renal renin and AT1R levels. However, in the HS+E and HS+V groups, enalapril and valsartan failed to influence renal renalase expression but abolished the increase in proteinuria, renal cortex renin, and AT1R levels with respect to the HS group. CONCLUSION: This study indicates that high salt intake reduces renal expression, and renal RAS may be not involved in the regulation of renalase in SD rats fed with high-salt diet.

Molecular background and physiological consequences of altered peripheral serotonin homeostasis in adult rats perinatally treated with tranylcypromine.

Serotonin (5-hydroxytryptamine, 5-HT) is a biologically active molecule present in mammals in the brain and peripheral tissues where it exerts many physiological functions. Developmental exposure to 5-HT-enhancing agents has been reported to induce long-lasting changes in the brain, but the long-term effects of perinatal 5-HT enhancement on 5-HT balance and function in the peripheral compartment have not been explored. Perinatal treatment of rats with monoamine oxidase (MAO) inhibitor tranylcypromine (TCP), leads to persistent imbalance in central (increased 5-HT degradation and decreased 5-HT concentrations in the brain) and peripheral (increased platelet and decreased plasma 5-HT concentrations) 5-HT homeostasis. In this study, we explored the molecular background of peripheral 5-HT imbalance, and its possible consequences on bone remodeling and hematopoiesis. Jejunum, liver and blood samples were collected from TCP- and saline-treated rats on post-natal day 70. Relative mRNA levels for tryptophan hydroxylase 1 (TPH1) and MAO A were analyzed using quantitative RT-PCR, femoral trabecular bone parameters were measured using microcomputed tomography, while peripheral blood cell number was determined by cell counter. TCP-treated rats displayed significant decrease in expression of Tph1, and significant increase in percentage of bone volume, trabecular number, connectivity density, and leukocyte number. In addition, significant negative correlation was observed between relative concentrations of TPH1 mRNA and trabecular bone parameters. Our results: a) show that perinatal exposure to tranylcypromine leads to long-lasting compensatory decrease in Tph1 expression in the peripheral compartment, accompanied with alterations in bone remodeling and hematopoiesis, b) suggest that peripheral and central 5HT compartment use different strategies to compensate for 5-HT imbalances of the same cause, and c) indicate dominant role of peripheral over central 5-HT in the regulation of bone maintenance, as well as possible negative in vivo influence of peripheral 5-HT on leukocyte development and/or sustainment.

Atorvastatin improves Y-maze learning behaviour in nicotine treated male albino rats.

Nicotine is a parasympathomimetic alkaloid present in tobacco which can induce hyperlipidemia and has a direct effect on neural functions. Statins, competitive inhibitors of 3-hydroxymethyl-3-glutaryl-coenzyme-A reductase, are cholesterol lowering drugs. It has some neuroprotective effects. Hence we analysed the combined effect of nicotine and statin on the learning behaviour of male albino rats. We employed Y-Maze conditional discrimination task. Rats were divided into 4 groups with six rats in each group. (1) Control, (2) Atorvastatin (10mg/kgb.wt), (3) Nicotine (0.6mg/kgb.wt) and (4) Atorvastatin (10mg/kgb.wt)+Nicotine (0.6mg/kgb.wt). After 30days of treatment rats from each group were selected for behavioural study and they were observed for 30days. At the end of the experimental period rats were sacrificed, and brain and liver were dissected out for further biochemical analysis. Nicotine treated group showed least performance in learning in comparison with control, atorvastatin and atorvastatin+nicotine treated groups. Co-administration of atorvastatin and nicotine improved learning behaviour compared to nicotine treated group. Reactive oxygen species level was significantly increased in nicotine group compared to control. The level of neurotransmitter serotonin which has a significant role in learning was found to be decreased in nicotine treated group compared to the control group. Activity of Na(+) K(+) ATPase, Ca(2+) ATPase and glutathione content was significantly reduced in nicotine treated group compared to control. The activity of acetylcholine esterase was significantly increased in the nicotine treated group. Expression studies showed significant decrease in N-methyl D-aspartate receptors and increase in mono amine oxidase-A and mono amine oxidase-B in nicotine treated group and was reversed in atorvastatin + nicotine treated group. It can be concluded that co-administration of nicotine with statin ameliorates the neural functional alterations caused by nicotine to a significant level.

Post-Transcriptional Regulation of Renalase Gene by miR-29 and miR-146 MicroRNAs: Implications for Cardiometabolic Disorders.

Renalase, a recently identified oxidoreductase, is emerging as a novel regulator of cardiovascular and metabolic disease states. The mechanism of regulation of renalase gene, especially at the post-transcriptional level, is completely unknown. We set out to investigate the possible role of microRNAs in regulation of renalase gene in this study. Computational predictions using multiple algorithms coupled with systematic functional analysis revealed specific interactions of miR-29a/b/c and miR-146a/b with mouse and human renalase 3'-UTR (untranslated region) in cultured cells. Next, we estimated miR-29b and miR-146a, as well as renalase expression, in genetically hypertensive blood pressure high and genetically hypotensive blood pressure low mice. Kidney tissues from blood pressure high mice showed diminished (~1.6- to 1.8-fold) renalase mRNA/protein levels and elevated (~2.2-fold) miR-29b levels as compared to blood pressure low mice. A common single nucleotide polymorphism in human renalase 3'-UTR (C/T; rs10749571) creates a binding site for miR-146a; consistently, miR-146a down-regulated human renalase 3'-UTR/luciferase activity in case of the T allele suggesting its potential role in regulation of renalase in humans. Indeed, genome-wide association studies revealed directionally concordant association of rs10749571 with diastolic blood pressure, glucose and triglyceride levels in large human populations (n ≈ 58,000-96,000 subjects). This study provides evidence for post-transcriptional regulation of renalase gene by miR-29 and miR-146 and has implications for inter-individual variations on cardiometabolic traits.

Chemotaxis of Escherichia coli to norepinephrine (NE) requires conversion of NE to 3,4-dihydroxymandelic acid.

Norepinephrine (NE), the primary neurotransmitter of the sympathetic nervous system, has been reported to be a chemoattractant for enterohemorrhagic Escherichia coli (EHEC). Here we show that nonpathogenic E. coli K-12 grown in the presence of 2 µM NE is also attracted to NE. Growth with NE induces transcription of genes encoding the tyramine oxidase, TynA, and the aromatic aldehyde dehydrogenase, FeaB, whose respective activities can, in principle, convert NE to 3,4-dihydroxymandelic acid (DHMA). Our results indicate that the apparent attractant response to NE is in fact chemotaxis to DHMA, which was found to be a strong attractant for E. coli. Only strains of E. coli K-12 that produce TynA and FeaB exhibited an attractant response to NE. We demonstrate that DHMA is sensed by the serine chemoreceptor Tsr and that the chemotaxis response requires an intact serine-binding site. The threshold concentration for detection is ≤5 nM DHMA, and the response is inhibited at DHMA concentrations above 50 µM. Cells producing a heterodimeric Tsr receptor containing only one functional serine-binding site still respond like the wild type to low concentrations of DHMA, but their response persists at higher concentrations. We propose that chemotaxis to DHMA generated from NE by bacteria that have already colonized the intestinal epithelium may recruit E. coli and other enteric bacteria that possess a Tsr-like receptor to preferred sites of infection.

Chemotherapy-induced monoamine oxidase expression in prostate carcinoma functions as a cytoprotective resistance enzyme and associates with clinical outcomes.

To identify molecular alterations in prostate cancers associating with relapse following neoadjuvant chemotherapy and radical prostatectomy patients with high-risk localized prostate cancer were enrolled into a phase I-II clinical trial of neoadjuvant chemotherapy with docetaxel and mitoxantrone followed by prostatectomy. Pre-treatment prostate tissue was acquired by needle biopsy and post-treatment tissue was acquired by prostatectomy. Prostate cancer gene expression measurements were determined in 31 patients who completed 4 cycles of neoadjuvant chemotherapy. We identified 141 genes with significant transcript level alterations following chemotherapy that associated with subsequent biochemical relapse. This group included the transcript encoding monoamine oxidase A (MAOA). In vitro, cytotoxic chemotherapy induced the expression of MAOA and elevated MAOA levels enhanced cell survival following docetaxel exposure. MAOA activity increased the levels of reactive oxygen species and increased the expression and nuclear translocation of HIF1α. The suppression of MAOA activity using the irreversible inhibitor clorgyline augmented the apoptotic responses induced by docetaxel. In summary, we determined that the expression of MAOA is induced by exposure to cytotoxic chemotherapy, increases HIF1α, and contributes to docetaxel resistance. As MAOA inhibitors have been approved for human use, regimens combining MAOA inhibitors with docetaxel may improve clinical outcomes.