Tyrosine Hydroxylase Expression Research Articles

Midbrain Dopamine Neurons Derived from Induced Pluripotent Stem Cells from Patients with Lesch Nyhan Disease and Gene-Edited Knock-In HPRT1 Mutations (P10-9.007)

<h3>Objective:</h3> To create a novel in-vitro model to study molecular pathogenesis of midbrain dopamine abnormalities during neuronal development in Lesch Nyhan disease (LND). <h3>Background:</h3> LND is a neurodevelopmental disease which manifests with neurobehavior abnormalities starting in early childhood. It is linked to abnormal development of nigrostriatal dopamine neurons. However, the molecular pathogenesis of impaired development is not well understood. One of the main reasons has been lack of a good model to study midbrain development. <h3>Design/Methods:</h3> We generated 24 induced pluripotent stem cell (iPSC) lines; 12 from 4 individuals with LND, and another 12 from 4 normal individuals. We also generated 12 gene-edited lines, all containing a c.C508&gt;T stop codon in the <i>HPRT1</i> gene. All 24 lines were assessed for pluripotency markers and several of the lines were differentiated into midbrain dopamine neurons using a floor-plate induction protocol. Differentiation was assessed at 3 stages of development in vitro: day 11 (neuroprogenitor), day 25 (early neuron) and day 60 (late neuron). The percentages of dopamine neurons were determined by tyrosine hydroxylase (TH) immunostaining with flow cytometry. The expression of FOXA2, TH and DAT were also measured by quantitative qPCR. Dopamine and its derivatives were measured using HPLC. <h3>Results:</h3> The differentiation protocol yielded a high percentage of TH-positive neurons (50–80%) that produced a high quantity of dopamine and its metabolites across all cell lines. TH and related markers all varied significantly among the different cell lines, and during differentiation. Results are being interrogated to identify any systematic changes between the LND and control lines. <h3>Conclusions:</h3> We have generated a large bank of iPSCs from individuals with LND, <i>HPRT1</i> gene-edited lines, and parallel control lines. We have shown that these lines can be used to generate developing dopamine neurons, providing a new model to investigate the molecular pathogenesis of LND. <b>Disclosure:</b> Ms. Seifar has nothing to disclose. Ms. Sutcliffe has nothing to disclose. Dr. Jinnah has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Takaha/Ene. Dr. Jinnah has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Ipsen. Dr. Jinnah has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Ipsen. Dr. Jinnah has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Abbvie. The institution of Dr. Jinnah has received research support from Addex. The institution of Dr. Jinnah has received research support from Aeon. The institution of Dr. Jinnah has received research support from Revance. The institution of Dr. Jinnah has received research support from Jazz.

High‐Density Optophysiology Platform for Recording Intracellular and Extracellular Signals across the Brain of Free‐Moving Animals

AbstractDeveloping a novel tool capable of real‐time monitoring and simultaneously quantifying of both intra/extracellular chemical signals across the large‐scale brain is the key bottleneck for understanding the interactions between the molecules inside and outside neurons. Here we built up a high‐density intra/extracellular optophysiology platform, together with developing two probes for specific recognition of L‐cysteine (Cys) and dopamine (DA), for simultaneously quantifying of both intracellular Cys and extracellular DA with high selectivity and accuracy across the brain of freely moving animals, as well as recording electrical signals. Using this powerful tool, it was found that intracellular Cys regulated extracellular DA through inducing the expression of tyrosine hydroxylase in the depressed mice brain. We also established the functional networks of Cys and DA across 32 brain regions in freely moving animals. More importantly, it was discovered that depression reduced the correlations between adjacent brain regions, which was recovered by the treatment of N‐acetyl‐l‐cysteine.

High-Density Optophysiology Platform for Recording Intracellular and Extracellular Signals across the Brain of Free-Moving Animals.

Developing a novel tool capable of real-time monitoring and simultaneously quantifying of both intra/extracellular chemical signals across the large-scale brain is the key bottleneck for understanding the interactions between the molecules inside and outside neurons. Here we built up a high-density intra/extracellular optophysiology platform, together with developing two probes for specific recognition of L-cysteine (Cys) and dopamine (DA), for simultaneously quantifying of both intracellular Cys and extracellular DA with high selectivity and accuracy across the brain of freely moving animals, as well as recording electrical signals. Using this powerful tool, it was found that intracellular Cys regulated extracellular DA through inducing the expression of tyrosine hydroxylase in the depressed mice brain. We also established the functional networks of Cys and DA across 32 brain regions in freely moving animals. More importantly, it was discovered that depression reduced the correlations between adjacent brain regions, which was recovered by the treatment of N-acetyl-l-cysteine.

Menstrual blood-derived endometrial stem cells alleviate neuroinflammation by modulating M1/M2 polarization in cell and rat Parkinson’s disease models

BackgroundNeuroinflammation is closely related to the development of Parkinson's disease (PD). Because of the extensive sources, non-invasive and periodical collection method, human menstrual blood-derived endometrial stem cells (MenSCs) have been explored as a promising tool for treatment of PD. This study aimed to investigate if MenSCs could inhibit neuroinflammation in PD rats by regulating M1/M2 polarization and to excavate the underlying mechanisms.MethodsMenSCs were co-cultured with 6-OHDA-exposed microglia cell lines. Then the morphology of microglia cells and the level of inflammatory factors were assessed by immunofluorescence and qRT-PCR. After MenSCs were transplanted into the brain of PD rats, animal motor function, the expression of tyrosine hydroxylase, and the level of inflammatory factors in the cerebrospinal fluid (CSF) and serum were detected to evaluate the therapeutic potential of MenSCs. Meanwhile, the expression of M1/M2 phenotype related genes was detected by qRT-PCR. One protein array kit containing 1000 kinds of factors was used to detect the protein components in the conditioned medium of MenSCs. Finally, bioinformatic analysis was performed to analyze the function of factors secreted by MenSCs and the signal pathways involved in.ResultsMenSCs could suppress 6-OHDA-induced microglia cell activation and significantly decrease inflammation in vitro. After transplantation into the brain of PD rats, MenSCs improved animal motor function, which was indicated by the increased movement distance, ambulatory episodes, exercise time on the rotarod, and less contralateral rotation. Additionally, MenSCs reduced the loss of dopaminergic neurons and down-regulated the level of pro-inflammatory factors in the CSF and serum. Moreover, q-PCR and WB results showed the transplantation of MenSCs significantly down-regulated the expression of M1 phenotype cell markers and meanwhile up-regulated the expression of M2 phenotype cell markers in the brain of PD rats. 176 biological processes including inflammatory response, negative regulation of apoptotic process, and microglial cell activation were enriched by GO-BP analysis. 58 signal pathways including PI3K/Akt and MAPK were enriched by KEGG analysis.ConclusionsIn conclusion, our results provide preliminary evidence for the anti-inflammation capacity of MenSCs by regulating M1/M2 polarization. We firstly demonstrated the biological process of factors secreted by MenSCs and the signal pathways involved in using protein array and bioinformatic analysis.

Leptin ameliorates Aβ1-42-induced Alzheimer's disease by suppressing inflammation via activating p-Akt signaling pathway.

Alzheimer's disease (AD) is characterized by progressive neuronal loss, cognitive disorder, and memory decline. Leptin has been reported to have a neuroprotective effect on neurodegenerative diseases. Our aim was to investigate whether intraperitoneal injection of leptin has a neuroprotective effect and to explore its underlying mechanisms in the AD mouse model. Aβ1-42 was injected into male C57BL/6J mice to construct an AD mouse model, and leptin was injected intraperitoneally to cure AD. The Morris water maze test was used to investigate spatial learning ability. Neuronal loss was tested by tyrosine hydroxylase expression in the hippocampus, and terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling assay was applied to detect neuronal apoptosis. Pro-inflammatory cytokine levels were monitored by RT-PCR and western blotting was selected to explore which signaling pathway leptin acted on. Leptin ameliorated spatial learning impairment, restored neuronal loss and apoptosis, and inhibited pro-inflammatory cytokine expression by activating the p-Akt signaling pathway in Aβ1-42-induced AD mice. Leptin ameliorates Aβ1-42-induced AD by suppressing inflammation via activating the p-Akt signaling pathway.

Electroacupuncture intervention on stress-induced cardiac autonomic imbalance in rats involves corticotropin-releasing hormone system activity.

Autonomic imbalance is a core aspect of stress response that strongly correlates to cardiovascular diseases. Enhanced activity of the central corticotropin-releasing hormone (CRH) system may result in autonomic imbalance to cause cardiovascular responses in a stress state. Electroacupuncture at PC6 acupoints has been demonstrated to prevent and treat cardiovascular diseases. In this study, we aim to demonstrate the protective role of electroacupuncture at PC6 in ameliorating cardiac autonomic imbalance and investigate the underlying mechanisms in immobilization stress rats. Four groups were subjected. Immobilization stress was applied to three groups. And the rats in two electroacupuncture-intervened groups exerted electroacupuncture at PC6 or tail respectively. Then, we performed ECG recording for heart rate variability (HRV) analysis, and rats were sacrificed after experiments for biological analysis. HRV analysis indicated that electroacupuncture at PC6 improved the enhanced low-frequency band of the power spectrum (LF), the reduced high-frequency band of the power spectrum (HF), and the enhanced LF/HF ratio caused by immobilization stress. Besides, electroacupuncture at PC6 significantly decreased phosphorylated tyrosine hydroxylase expression and increased acetylcholine esterase expression in heart of immobilization stress rats. Furthermore, electroacupuncture at PC6 significantly decreased CRH level and CRH 1 type receptor and CRH 2 type receptor (CRHR2) expressions in the rostral ventrolateral medulla (RVLM), and CRH level and CRHR2 expression in the nucleus of the solitary tract (NTS) of immobilization stress rats. Our findings suggest that electroacupuncture at PC6 can ameliorate stress-induced cardiac autonomic imbalance by modulating the CRHergic input in the RVLM and NTS.

From metabolism to behaviour – Multilevel effects of environmental methamphetamine concentrations on fish

Methamphetamine (METH) is a concerning drug of abuse that produces strong psychostimulant effects. The use of this substance, along with the insufficient removal in the sewage treatment plants, leads to its occurrence in the environment at low concentrations. In this study, brown trout (Salmo trutta fario) were exposed to 1 μg/L of METH as environmental relevant concentration for 28 days in order to elucidate the complex effects resulting from the drug, including behaviour, energetics, brain and gonad histology, brain metabolomics, and their relations. Trout exposed to METH displayed lowered activity as well as metabolic rate (MR), an altered morphology of brain and gonads as well as changes in brain metabolome when compared to controls. Increased activity and MR were correlated to an increased incidence of histopathology in gonads (females - vascular fluid and gonad staging; males - apoptotic spermatozoa and peritubular cells) in exposed trout compared to controls. Higher amounts of melatonin in brain were detected in exposed fish compared to controls. Tyrosine hydroxylase expression in locus coeruleus was related to the MR in exposed fish, but not in the control. Brain metabolomics indicated significant differences in 115 brain signals between control and METH exposed individuals, described by the coordinates within the principal component analyses (PCA) axes. These coordinates were subsequently used as indicators of a direct link between brain metabolomics, physiology, and behaviour - as activity and MR varied according to their values. Exposed fish showed an increased MR correlated with the metabolite position in PC1 axes, whereas the control had proportionately lower MR and PC1 coordinates. Our findings emphasize the possible complex disturbances in aquatic fauna on multiple interconnected levels (metabolism, physiology, behaviour) as a result of the presence of METH in aquatic environments. Thus, these outcomes can be useful in the development of AOP's (Adverse Outcome Pathways).

The interplay between lncRNA NR_030777 and SF3B3 in neuronal damage caused by paraquat

Paraquat (PQ) has been widely acknowledged as an environmental risk factor for Parkinson's disease (PD). However, the interaction between splicing factor and long non-coding RNA (lncRNA) in the process of PQ-induced PD has rarely been studied. Based on previous research, this study focused on splicing factor 3 subunit 3 (SF3B3) and lncRNA NR_030777. After changing the target gene expression level by lentiviral transfection technology, the related gene expression was detected by western blot and qRT-PCR. The expression of SF3B3 protein was reduced in Neuro-2a cells after PQ exposure, and the reactive oxygen species (ROS) scavenger N-acetylcysteine prevented this decline. Knockdown of SF3B3 reduced the PQ-triggered NR_030777 expression increase, and overexpression of NR_030777 reduced the transcriptional and translational level of Sf3b3. Then, knockdown of SF3B3 exacerbated the PQ-induced decrease in cell viability and aggravated the reduction of tyrosine hydroxylase (TH) protein expression. Overexpressing SF3B3 reversed the reduction of TH expression caused by PQ. Moreover, after intervention with the autophagy inhibitor Bafilomycin A1, LC3B-II protein expression was further increased in Neuro-2a cells with the knockdown of SF3B3, indicating that autophagy was enhanced. In conclusion, PQ modulated the interplay between NR_030777 and SF3B3 through ROS production, thereby impairing autophagic flux and causing neuronal damage.

Neural stem cells transplantation combined with ethyl stearate improve PD rats motor behavior by promoting NSCs migration and differentiation.

In recent years, the ability of neural stem cells (NSCs) transplantation to treat Parkinson's disease (PD) has attracted attention. However, it is still a challenge to promote the migration of NSCs to the lesion site and their directional differentiation into dopaminergic neurons in PD. C-C motif chemokine ligand 5 (CCL5) and C-C motif chemokine receptor 5 (CCR5) are expressed in the brain and are important regulators of cell migration. It has been reported that ethyl stearate (PubChem CID: 8122) has a protective effect in 6-OHDA-induced PD rats. Parkinson's disease rats were injected with 6-hydroxydopamine (6-OHDA) into the right substantia nigra, and striatum followed by 8μL of an NSC cell suspension containing 100 μM ethyl stearate and 8 × 105 cells in the right striatum. The effect of transplantation NSCs combined with ethyl stearate was assessed by evaluating apomorphine (APO)-induced turning behavior and performance in the pole test. Quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR), Western blotting (WB), and immunofluorescence staining were also performed. NSCs transplantation combined with ethyl stearate ameliorated the behavioral deficits of PD rats. PD rats that received transplantation NSCs combined with ethyl stearate exhibited increased expression of tyrosine hydroxylase (TH) and an increased number of green fluorescent protein (GFP)-positive cells. Furthermore, GFP-positive cells migrated into the substantia nigra and differentiated into dopaminergic neurons. The expression of CCL5 and CCR5 was significantly increased after transplantation NSCs combined with ethyl stearate. These findings suggest that NSCs transplantation combined with ethyl stearate can improve the motor behavioral performance of PD rats by promoting NSCs migration from the striatum to the substantia nigra via CCL5/CCR5 and promoting the differentiation of NSCs into dopaminergic neurons.

Impact of age on the rotenone-induced sporadic Parkinson's disease model using Drosophila melanogaster

Rotenone, a naturally occurring toxin, has been used to induce sporadic Parkinson's disease (PD) in Drosophila melanogaster for decades. However, the age of flies varies considerably between studies in this model. To investigate the impact of age on the rotenone-induced PD model, we collected male flies at the age of 1, 5, 7, and 10 days post-eclosion, respectively. Then, flies were immediately exposed to a feeding medium supplemented with 250 μM rotenone for seven days. The motor ability of Drosophila was detected by negative geotaxis assay, and the number of dopamine (DA) neurons and tyrosine hydroxylase (TH) expression levels were evaluated. The results showed that both the motor deficits and mortality increased with age. The flies older than five days showed typical PD features, including the loss of DA neurons, decreased TH expression levels, and decreased locomotive ability. However, 1-day-old flies displayed an unstable motor deficit and little TH expression changes after seven days of rotenone exposure. Lastly, after 7 days of exposure to rotenone, the death rate of flies rapidly increased with increasing starting age. The death rates of 1-, 5-, 7-, and 10-days old flies were 10.0%, 22.8%, 41.5%, and 50.4%, respectively. The findings of this study suggest that age is a crucial factor impacting the Drosophila PD model. This information provides a reference for the age selection to use this model for future studies.

Mesenchymal stem-cell-derived microvesicles ameliorate MPTP-induced neurotoxicity in mice: a role of the gut-microbiota-brain axis.

Parkinson's disease (PD) is a chronic and progressive neurodegenerative disorder. Increasing evidence suggests the role of the gut-microbiota-brain axis in the pathogenesis of PD. Mesenchymal stem-cell-derived microvesicles (MSC-MVs) have emerged as a therapeutic potential for neurological disorders over the last years. The objective of this study was to investigate whether MSC-MVs could improve PD-like neurotoxicity in mice after administration of MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine). MPTP-induced reductions in the dopamine transporter and tyrosine hydroxylase expressions in the striatum and substantia nigra (SNr) were attenuated after a subsequent single administration of MSC-MVs. Increases in the phosphorylated α-synuclein (p-α-Syn)/α-Syn ratio in the striatum, SNr, and colon after MPTP injection were also attenuated after MSC-MVs injection. Furthermore, MSC-MVs restored MPTP-induced abnormalities of the gut microbiota composition. Interestingly, positive correlations between the genus Dubosiella and the p-α-Syn/α-Syn ratio were observed in the brain and colon, suggesting their roles in the gut-microbiota-brain communication. Moreover, MSC-MVs attenuated MPTP-induced reduction of the metabolite, 3,6-dihydroxy-2-[3-methoxy-4-(sulfooxy)phenyl]-7-(sulfinooxy)-3,4-dihydro-2H-1-benzopyran-5-olate, in the blood. Interestingly, a negative correlation between this compound and the p-α-Syn/α-Syn ratio was observed in the brain and colon. These data suggest that MSC-MVs could ameliorate MPTP-induced neurotoxicity in the brain and colon via the gut-microbiota-brain axis. Therefore, MSC-MVs would have a new therapeutic potential for neurological disorders such as PD.

Chaihu and Longgu Muli Decoction demonstrate neuroprotective effects in the rat model of Parkinson's disease with depression by regulating the AMPK/mTOR signaling pathway

BackgroundChaihu and Longgu Muli decoction (CLMD) has been used as a classical prescription of traditional Chinese medicine (TCM) prescription to treat Parkinson's disease with depression (PDD). Nevertheless, the potential mechanisms underlying their neuroprotective effects are not well-understood. PurposeTo evaluate the neuroprotective effects and possible involvement of a molecular signaling pathway of CLMD in a PDD rat model. MethodsAdult male SD rats were randomly divided into six groups: control, model, positive (madopar 0.032 g kg−1 day−1), low dosage (L, 5 g kg−1 day−1), medium dosage (M, 10 g kg−1 day−1) and high dosage (H, 20 g kg−1 day−1) of CLMD. The neuroprotective effects of CLMD were investigated using behavioral tests, immunohistochemistry, immunofluorescence, high-performance liquid chromatography (HPLC), and Nissl staining. Western blotting was used to further investigate the mechanism of action of CLMD. The protein expression of LC3, AMPK, p-AMPK, mTOR, and p-mTOR were examined. ResultsCLMD exhibited a protective effect on dopaminergic neurons by increasing the expression of tyrosine hydroxylase, which was predicted to be decreased by rotenone. CLMD restored behavior impaired by rotenone and increased the degradation of α-Syn aggregation to reduce tyrosine hydroxylase loss. Additionally, it upregulated the expression of LC3, p-AMPK/AMPK, and downregulated the expression of p-mTOR/mTOR. Conclusion: These findings provide evidence that CLMD restored behavior performance, protected dopaminergic neurons and activated autophagy by regulating the AMPK/mTOR signaling pathway in rat model of PDD. CLMD restored behavior and protected dopaminergic neurons by regulating the AMPK/mTOR signaling pathway to induce autophagy and inhibit apoptotic activity.

Overexpression of tyrosine hydroxylase in dopaminergic neurons increased sensitivity to methamphetamine

Drug abuse is one of the great social problems in the world and a major healthcare challenge. It is supposed that sensitivity and reactivity to abuse drugs may vary from person to person, while its molecular basis is largely unknown. Dopaminergic neurons are deeply involved in addiction, and tyrosine hydroxylase (TH) catalyzes the first and rate-limiting step of the biosynthesis of dopamine (DA). We investigated the effects of increased TH expression on the metabolism of DA and reactivity to methamphetamine (METH), a drug of abuse, in mice. Wild-type TH (WT-TH) or the S40E mutant of TH (S40E-TH), which is an active form of TH mimicking phosphorylated TH at the 40th serine, was expressed in midbrain dopaminergic neurons using an adeno-associated virus (AAV) vector. The biochemical analysis showed that the turnover rates of DA in the nerve terminals were increased by the expression of WT-TH and S40E-TH, while there were few changes in the DA contents. Next, we administered METH to TH-overexpressing mice. We found that the S40E-TH-expressing mice responded to lower doses of METH than the control mice and WT-TH mice. The stereotyped behaviors appeared first in S40E-TH mice and then in WT-TH and control mice in this order. These data showed that the TH activity and expression level differentially affect DA metabolism in the nerve terminals from that in the cell bodies and that the TH activity and expression level are one of the determining factors for sensitivity and reactivity to METH. We suggest that TH may be a drug target for ameliorating sensitivity to drugs of abuse.

Ginsenoside Rk1 prevents 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced Parkinson's disease via activating silence information regulator 3-mediated Nrf2/HO-1 signaling pathway.

Objectives:Ginsenoside Rk1, a novel ginsenoside isolated from red ginseng, has anti-inflammatory and anti-tumor activities. This study was designed to elucidate therole of RK1 in an in vitro1-methyl-4-phenylpyridinium (MPP+) cell model and an in vivo1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) of Parkinson's disease (PD).Methods: The grasping test, pole-climbing test,androtarod testwere performed to measure the effects of RK1 on MPTP-induced motor disorders.The expression of tyrosine hydroxylase (TH) and IBA-1were evaluated by western blotting.CCK-8 and flow cytometry assays were utilized to assess cell viability and apoptosis.Reactive oxygen species (ROS), Lactate dehydrogenase (LDH), and superoxide dismutase (SOD) were detected to analyze the effects of RK1 on oxidative stress. The levels of inflammatory cytokines were evaluated byenzyme-linked immunosorbent assay (ELISA).Results: The results showed that RK1 allayed motor deficitelicited by MPTP in a mouse model.RK1 administration augmented tyrosine hydroxylase (TH) expression in the brain striatum and substantia nigra (SN) of MPTP-treated mice.Moreover, RK1pretreatment promotedviability and suppressed apoptosis in MPP+-induced PC-12cells. Further, RK1 also attenuated MPP+-stimulatedoxidative stressand inflammatory response in PC-12 cells. Besides,RK1 augmented thelevel of SIRT3, and SIRT3 deletion counteracted RK1-induced repression on MPP+-elicited apoptosis, oxidative stress, and inflammatory response in PC-12 cells via modulating the Nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway.Conclusions: RK1mightexertneuroprotective effectsagainst MPP+/MPTP-induced neurotoxicity via activating SIRT3-mediated Nrf2/HO-1 signaling.RK1 might be a promising candidate against PD.

Association of Cognitive Deficit with Glutamate and Insulin Signaling in a Rat Model of Parkinson's Disease.

Cognitive deficit is a frequent non-motor symptom in Parkinson's disease (PD) with an unclear pathogenesis. Recent research indicates possible involvement of insulin resistance and glutamate excitotoxicity in PD development. We investigated cognitive performance and the brain glutamate and insulin signaling in a rat model of PD induced by bilateral intrastriatal injection of 6-hydroxydopamine (6-OHDA). Cognitive functions were assessed with Passive Avoidance (PA) and Morris Water Maze (MWM) tests. The expression of tyrosine hydroxylase (TH) and proteins involved in insulin (insulin receptor - IR, phosphoinositide 3 kinase - pI3K, extracellular signal-regulated kinases-ERK) and glutamate receptor (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptos-AMPAR, N-methyl-D-aspartate receptor - NMDAR) signaling was assessed in the hippocampus (HPC), hypothalamus (HPT) and striatum (S) by immunofluorescence, Western blot and enzyme-linked immunosorbent assay (ELISA). Three months after 6-OHDA treatment, cognitive deficit was accompanied by decreased AMPAR activity and TH levels (HPC, S), while levels of the proteins involved in insulin signaling remained largely unchanged. Spearman's rank correlation revealed a strong positive correlation for pAMPAR-PA (S), pNMDAR-pI3K (HPC) and pNMDAR-IR (all regions). Additionally, a positive correlation was found for TH-ERK and TH-pI3K, and a negative one for TH-MWM/errors and pI3K-MWM/time (S). These results suggest a possible association between brain glutamate (but not insulin) signaling dysfunction and cognitive deficit in a rat PD model, detected three months after 6-OHDA treatment.

Paeoniflorin protects 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced Parkinson's disease mice by inhibiting oxidative stress and neuronal apoptosis through activating the Nrf2/HO-1 signaling pathway.

This study aimed to explore the neuroprotective effects of paeoniflorin on oxidative stress and apoptosis in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease (PD) mice. The effects of paeoniflorin on motor function in mice were evaluated by behavioral test. Then substantia nigra of mice were collected and neuronal damage was assessed using Nissl staining. Positive expression of tyrosine hydroxylase (TH) was detected by immunohistochemistry. Levels of malondialdehyde, superoxide dismutase (SOD) and glutathione were measured by biochemical method. terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay was used to detect apoptosis of dopaminergic neurons. Western blotting and real-time fluorescence quantitative PCR were used to detect the protein and mRNA expressions of Nrf2, heme oxygenase-1 (HO-1), B-cell lymphoma-2(Bcl-2), Bax and cleaved caspase-3. Paeoniflorin treatment significantly ameliorated the motor performance impairment in MPTP-induced PD mice. Moreover, it notably increased the positive expression rate of TH and reduced the damage and apoptosis of dopaminergic neurons in the substantia nigra. Furthermore, paeoniflorin increased the levels of SOD and glutathione and decreased the malondialdehyde content. It also promoted Nrf2 nuclear translocation, increased the protein and mRNA expressions of HO-1 and Bcl-2 and reduced the protein and mRNA expressions of BCL2-Associated X2 (Bax) and cleaved caspase-3. Treatment with the Nrf2 inhibitor, ML385, notably reduced the effects of paeoniflorin in MPTP-induced PD mice. Neuroprotective effects of paeoniflorin in MPTP-induced PD mice may be mediated via inhibition of oxidative stress and apoptosis of dopaminergic neurons in substantia nigra through activation of the Nrf2/HO-1 signaling pathway.

Downregulation of microRNA-330-5p induces manic-like behaviors in REM sleep-deprived rats by enhancing tyrosine hydroxylase expression.

In our pilot study, we found an increase in tyrosine hydroxylase (Th) mRNA expression in the prefrontal cortex of 72-h REM sleep-deprived (SD) rats, a mania model. Additionally, the expression levels of miR-325-3p, miR-326-3p, and miR-330-5p, the predicted target miRNAs on TH, were significantly decreased. Based on these results, in this study, we investigated whether miRNA-325-3p, miR-326-3p, and miR-330-5p modulate TH and manic-like behaviors in SD rats. Manic-like behaviors were assessed using the open field test (OFT) and elevated plus-maze (EPM) test. The direct binding activity of miRNAs to the 3'-untranslated region (3'-UTR) of the Th gene was measured in HEK-293 cells using a luciferase reporter system. We also examined mRNA and protein expression of TH after intracerebroventricular (ICV) injection of miR-330-5p agomir to SD rats, along with manic-like behaviors. We observed an upregulation in mRNA and protein expression of TH and downregulation in miRNA-325-3p, miR-326-3p, and miR-330-5p expressions in the prefrontal cortex of SD rats, together with increased manic-like behaviors. The luciferase reporter assay showed that miR-330-5p could repress TH expression through direct binding to its target site in the 3'-UTR of Th, whereas miR-326-3p and miR-330-5p could not. In addition, ICV injection of miR-330-5p agomir alleviated the increase in TH expression in the prefrontal cortex of SD rats and manic-like behaviors. TH expression regulation through miR-330-5p may be implicated in the pathophysiology of mania in SD rats.

Interplay between APP and glypican-1 processing and α-synuclein aggregation in undifferentiated and differentiated human neural progenitor cells.

In Parkinson's disease, there is an accumulation of α-synuclein (SYN) aggregates in neurons, which is promoted by neuroinflammation. In neural cells, cytokine-induced SYN aggregation is modulated by heparan sulfate (HS) derived from glypican-1 (GPC1) by amyloid precursor protein (APP) and nitric oxide (NO)-dependent cleavage. We have explored possible interplay between APP, GPC1, and SYN in undifferentiated and differentiated neural progenitor cells (NPCs) by modulating APP and GPC1 processing. Effects were monitored by immunofluorescence microscopy and slot immunoblotting using antibodies recognizing APP degradation products, HS released from GPC1, and SYN aggregates (filamentous SYN [SYNfil]). Suppression of HS release from GPC1 by inhibition of β-secretase or by NO deprivation resulted in no or slight increase in SYNfil aggregation. Stimulation of HS release by ascorbate did not further increase SYNfil staining. Interleukin-6 (IL-6) induced increased APP and GPC1 processing and SYNfil formation, which was reduced when β-secretase was inhibited and when HS release was impeded by NO deprivation. Ascorbate restored APP and GPC1 processing but did not affect SYNfil formation. Ascorbate-dependent differentiation of NPC resulted in the expression of tyrosine hydroxylase (TH) which colocalized with SYNfil. Suppression of APP processing by inhibition of β-secretase greatly disturbed the differentiation process. IL-6 induced coclustering of APP-degradation products, TH, HS, and SYNfil, which could be reversed by stimulation of HS release from GPC1 by excess ascorbate. We suggest that continuous release of HS from GPC1 moderates SYN aggregation and supports differentiation of NPC to dopaminergic neurons.

Role of saffron and chamomile in Parkinson diseases.

Madam, Parkinson's disease (PD) is a distinctive neurodegenerative disorder with a multifactorial range of etiology and symptoms. The pathophysiology behind the condition is a complex array of abnormal alpha-synuclein aggregation, mitochondrial dysfunction, oxidative stress, and neuroinflammation that leads to reduced dopaminergic expression, and neuronal cell death (1, 2). In multitudinous preclinical studies, Saffron and Chamomile are effective in treating PD. Saffron can mitigate the neurodegenerative progression of the disease by curtailing dopaminergic and neuronal loss and inhibiting alpha-synuclein aggregation. It also possesses antioxidant and anti-inflammatory activities (3). In-silico studies also demonstrated the action of active compounds of Saffron, including crocin, crocetin, and safranal, against potential targets of PD (1). Chamomile and its active compound Apigenin are beneficial in movement disorders in Parkinson's disease (4). It possesses neuroprotective, anti-inflammatory and antioxidant activities. It also has demonstrated activity against potential biomarkers of PD, including: Interleukin-6, Tumor Necrotic factor-alpha, Malonaldehyde, alpha-synuclein, Glial fibrillary acidic protein and also on Tyrosine Hydroxylase and dopamine receptors expression (2). Prolonged use of pharmacotherapy is not very beneficial in managing PD. Currently, dopamine-related drugs, including Levodopa, are considered first-line therapy. Despite temporarily alleviating the symptoms they cannot alter the degenerative process of PD (1). It warrants a crucial need for novel therapeutic agents working with diverse mechanisms. Pre-clinically, Saffron and chamomile are efficacious in altering potential disease biomarkers. Both herbs have been easily accessible and utilized since ancient times with numerous benefits and better tolerability. Clinical studies specifically for PD are yet to be analyzed; in different neurological disorders, daily oral consumption of 30mg of Saffron and 1gm to 1.5gm of Chamomile is recommended (3,5). Considering the high cost, a blended intake of saffron and Chamomile could be cost-effective and beneficial in treating the disease. Therefore, though clinical trials are needed for further elaboration, Parkinson's disease and related neurological disorders can be managed by synergising both drugs.

The role of tyrosine hydroxylase within dapoxetine-assisted therapy against premature ejaculation.

There are several investigations that have revealed that cerebral dopamine (DA) plays a pivotal role in the occurrence of premature ejaculation (PE). Although tyrosine hydroxylase (TH) is an essential enzyme for the synthesis of DA, only few investigations have described the role of TH in regulation mechanisms for ejaculation till now. To investigate whether there is a correlation between TH expression level in the brain and different ejaculation behavior in rats. Then explore whether the TH expression in the brain will change after acute dapoxetine treatment in rats with Rapid ejaculation. Rats (male, S-D rats, 6-8 weeks) were separated into three groups based on their ejaculation frequency: Rapid, Normal, and Sluggish. Expression level of DA in the brain was determined by enzyme-linked immune sorbent assay (ELISA) kit, TH expression level in the brain was determined by immunohistochemistry and Western Blot (WB) techniques. Among the three groups, DA and TH expression level were the highest in the Rapid ejaculation group, while the lowest was the Sluggish ejaculation group. The results also showed that TH level was positively associated with ejaculation frequency (r = 0.8038, P < 0.001) and negatively associated with ejaculation latency (r=-0.6199, P = 0.018). Furthermore, acute dapoxetine therapy in rats with Rapid ejaculation downregulated TH level in the brain. Changes in ejaculation behavior were significantly linked with TH level. Upregulated TH in selected brain regions related with ejaculation could cause rapid ejaculation. The effect of dapoxetine in prolonging ejaculation could be related to TH downregulation within the brain.