NMDA Receptors in the Rat Paraventricular Thalamic Nucleus Reduce the Naloxone-induced Morphine Withdrawal.

BACKGROUND: NMDA receptors have a significant role in the development of opioid physical dependence. Evidence demonstrated that a drug of abuse enhances neuronal excitability in the Paraventricular Nucleus (PVT). The current research studied whether blocking NMDA receptors through the administration of MK801 in the PVT nucleus could affect the development of Morphine (Mor) dependence and hence the behavioral indices induced by morphine withdrawal in rats. METHODS: Male Wistar rats weighing 250-300 g were used. For induction of drug dependence, we injected Mor subcutaneously (s.c.) (6, 16, 26, 36, 46, 56, and 66 mg/kg, 2 ml/kg) at an interval of 24 hours for 7 days. Animals were divided into two groups in which the NMDA receptor antagonist, MK801 (20 mM in 0.1 ml), or its vehicle were applied into the PVT nucleus for 7 days before each Mor administration. On day 8, after injection of naloxone (Nal, 2.5 mg/kg, i.p.), withdrawal behaviors were checked for 25 min. RESULTS: The current results demonstrated that the blockade of the NMDA receptor in the PVT nucleus significantly increased withdrawal behaviors provoked by the application of Nal in morphinedependent (Mor-d) rats. CONCLUSION: We concluded that the NMDA receptor in the PVT nucleus changes the development of Mor dependence.

Fluorescence inner filters of Arthrospira platensis: Novel perspective for precise fluorescence-based sensors.

Microalgae have been reputed as novel biological materials due to their unique structure, surface functionality and optical activity, making them worthwhile agents in biosensing and theranostic applications. However, further scrutiny is required for utilizing them in routine optical techniques due to their complex structure and diverse chemical components. Here, laser induced fluorescence (LIF) features of a bio-compatible microalgae i. e. Arthrospira platensis (Spirulina) have been assessed. Typical fluorescence properties as well as the inner filter effects (IFEs) were examined and revealed to be strongly dependent on concentration, excitation wavelength, and detection geometry as well. IFEs and resulting spectral shifts have been analyzed considering various SP chromophores, reabsorption processes, and resonance energy transfer (RET) mainly from "Carotenoids to Phycobilisomes" as well as "Phycobilisomes to Chlorophyll-a". As a result, LIF spectral shift due to the re-absorption events (secondary-IFE) is introduced as a credible parameter for design of precise fluorescence-based sensors, due to being less dependent on ambient noises. We hope that the findings provide novel features regarding the LIF of Spirulina (SP) that could be utilized to design and develop optical sensors in the field of photonics, material diagnosis and biomedical theranostics.

The effects of a chalcone derivative on memory, hippocampal corticosterone and BDNF levels in adult rats.

Purpose/Aim of the study: Since chalcones belong to the flavonoid family, the effects of a new synthetic chalcone derivative on memory, chronic stress, and expression of hippocampal BDNF gene were studied.Materials and methods: In this experiment, the male wistar rats were placed under restraint stress (6 h/day) for 21 days and then treated with a newly synthesized chalcone, containing methoxy on the aromatic rings or vehicles (20 mg/kg, intraperitoneal, IP). After the behavioral Passive avoidance, Open field, and Morris water maze tests, the levels of serum corticosterone (CORT) and hippocampal brain-derived neurotrophic factor (BDNF) were analyzed.Results: Results of these tests presented significant differences between the Stress (St) and Chalcone (Ch) groups. Chronic stress led to high CORT levels and impaired memory functions. Moreover, a single dose of synthetic chalcone in the St group could postpone memory impairments. Furthermore, a 20 mg/kg IP injection of chalcone markedly attenuated the decrease of hippocampal BDNF.Conclusions: It has been already proposed that flavonoids have beneficial effects on different types of memory. According to these results, further investigations are required to explore other factors besides BDNF that could be acutely modulated by chalcones.

Administration of Orexin-A into the Rat Thalamic Paraventricular Nucleus Enhances the Naloxone Induced Morphine Withdrawal.

OBJECTIVE: Orexin neuropeptides are implicated in physical dependence on opioids and expression of withdrawal symptoms in drug abuse. The paraventricular nucleus of the midline thalamus (PVT) has a high expression of orexin receptors. The current research studied the effect of orexin-A in the PVT area on the development of behavioral indices produced by morphine withdrawal in rats. METHODS: Male Wistar rats weighing 250-300 gr were utilised. To produce drug dependence, morphine (6, 16, 26, 36, 46, 56, and 66 mg/kg, 2 ml/kg) was injected at an interval of 24 hrs for 7 days. To assess the involvement of the orexin in withdrawal syndrome, we injected orexin-A (100 µM, 200 nl) into the PVT for 7 days before each morphine injection. On the day after the last injection of morphine, naloxone (2.5 mg/kg, i.p.) was injected to elicit the morphine withdrawal symptoms which were observed and checked for 25 min. RESULTS: The results of the current research showed that the orexin-A in PVT enhances the severity of behavioral symptoms prompted by the injection of naloxone in drug-dependent rats. CONCLUSIONS: These observations imply that targeting the orexin receptors in PVT might exhibit a new therapeutic strategy for the future treatment of dependence.

Thymol protects against 6-hydroxydopamine-induced neurotoxicity in in vivo and in vitro model of Parkinson's disease via inhibiting oxidative stress.

BACKGROUND: Parkinson's disease (PD) is a multifactorial movement disorder with the progressive degeneration of the nigrostriatal system that impairs patients' movement ability. Oxidative stress has been found to affect the etiology and pathogenesis of PD. Thymol, a monoterpenic phenol, is one of the most important dietary constituents in thyme species. It has been used in traditional medicine and possesses some properties including antioxidant, free radical scavenging, anti-inflammatory. In this study, in vitro and in vivo experiments were performed with the thymol in order to investigate its potential neuroprotective effects in models of PD. METHODS: The present study aimed to evaluate the therapeutic potential of thymol in 6-hydroxydopamine (6-OHDA)-induced cellular and animal models of PD.  RESULTS: Post-treatment with thymol in vitro was found to protect PC12 cells from toxicity induced by 6-OHDA administration in a dose-dependent manner by (1) increasing cell viability and (2) reduction in intracellular reactive oxygen species, intracellular lipid peroxidation, and annexin-positive cells. In vivo, post-treatment with thymol was protective against neurodegenerative phenotypes associated with systemic administration of 6-OHDA. Results indicated that thymol improved the locomotor activity, catalepsy, akinesia, bradykinesia, and motor coordination and reduced the apomorphine-caused rotation in 6-OHDA-stimulated rats. Increased level of reduced glutathione content and a decreased level of MDA (malondialdehyde) in striatum were observed in the 6-OHDA rats post-treated with thymol. CONCLUSIONS: Collectively, our findings suggest that thymol exerts protective effects, possibly related to an anti-oxidation mechanism, in these in vitro and in vivo models of Parkinson's disease.

ß-Amyloid Formation, Memory, and Learning Decline Following Long-term Ovariectomy and Its Inhibition by Systemic Administration of Apigenin and ß-Estradiol.

INTRODUCTION: The increasing cases of Alzheimer Disease (AD) has caused numerous problems. The risk of developing AD increases in menopausal women, too. Apigenin and ß-estradiol are effective antioxidant and neuroprotective agents. We conducted the present study to explore their combined effects on ß-amyloid plaque formation, memory, and learning in ovariectomized rats. METHODS: Forty-two Wistar rats were randomly assigned into 6 groups: 1) ovariectomized (OVX), 2) OVX + apigenin, 3) OVX + ß-estradiol, 4) OVX + apigenin + ß-estradiol, 5 &6) vehicle shams for E2 and API, and 7) surgical sham. Treatment was done with apigenin and ß-estradiol. Then, we studied the formation of ß-amyloid plaques, neuronal density in the hippocampus area, apoptosis, memory, and learning. RESULTS: Findings showed the significant formation of ß-amyloid plaques in the hippocampus of OVX animals and their memory impairment. Apigenin and ß-estradiol significantly reduced the number of ß-amyloid plaques, as well as the symptoms of memory impairment and learning, and decreased the expression of caspase-3 in treated animals. CONCLUSION: Accordingly, ß-estradiol and apigenin could have more potent therapeutic effects on AD.

Neurogenesis in the rat neonate's hippocampus with maternal short-term REM sleep deprivation restores by royal jelly treatment.

BACKGROUND: Numerous studies have shown the effects of rapid eye movement sleep deprivation (REM-SD) on behavior and brain structures. The impact of REM-SD on learning and memory, thus neurogenesis, has been reported in previous studies. Royal jelly (RJ) is known as the wealthiest biological nutrient with various physiological properties. This study aimed to study the possible effect of RJ on neurogenesis of the rat hippocampus neonates following exposure of mother to REM-SD during pregnancy. METHODS: Thirty neonate rats from 15 pregnant Wistar rats were used. To induce REM-SD, the flowerpot method was used. The pregnant rats were divided into five groups (n = 3): group 1, no treatment; group 2, REM-SD; groups 3, 4, and 5, REM-SD +RJ. The former group received 72 h REM-SD during pregnancy (days 7, 14, 21), and the latter group received REM-SD + RJ (three trial groups). At week 4, the rat neonates of all groups were sacrificed (n = 6 each group). Their brains were fixed, removed, and prepared for Nissl and Hoechst 33342 staining. By using real time polymerase chain reaction methode the brain-derived neurotrophic factor BDNF gene expression was studied (RT-PCR), brain-derived neurotrophic factor (BDNF) gene expression was studied. The results were analyzed statistically, and the Pv  < .05 was considered significant. RESULTS: The results showed a significant decrease in the number of neurons in the hippocampus of neonatal rats of REM-SD mothers compared to the neonates of the mother with REM-SD + RJ. REM-SD also led to an increase in apoptosis reaching the neonates from the REM-SD + RJ animals. High expression of BDNF was observed in the hippocampus of the neonates from REM-SD + RJ treated mothers. CONCLUSION: RJ acts as a neuroprotective agent that could compensate for the effects of REM-SD on learning and memory via restoring neurogenesis.

Carvacrol Protects Against 6-Hydroxydopamine-Induced Neurotoxicity in In Vivo and In Vitro Models of Parkinson's Disease.

Parkinson's disease (PD) is a progressive neurodegenerative movement disorder characterized by selective loss of dopaminergic neurons that project from the substantia nigra pars compacta to the striatum. Evidence from human and animal studies has suggested that oxidative damage critically contributes to neuronal loss in PD. Carvacrol (CAR), a monoterpenic phenol, is the main constituents in the essential oil of many aromatic plants and possesses some properties including anti-inflammatory and anti-oxidant effects. In this study, in vitro and in vivo experiments were performed with the CAR in order to investigate its potential neuroprotective effects in models of PD. Post-treatment with CAR in vitro was found to protect rat adrenal pheochromocytoma PC12 cells from toxicity induced by 6-hydroxydopamine (6-OHDA) administration in a dose-dependent manner by (1) increasing cell viability and (2) reduction in intracellular reactive oxygen species, intracellular lipid peroxidation, and annexin-positive cells. In vivo, post-treatment with CAR (15 and 20 mg/kg) was protective against neurodegenerative phenotypes associated with systemic administration of 6-OHDA. Results indicated that CAR improved the locomotor activity, catalepsy, akinesia, bradykinesia, and motor coordination and reduced the apomorphine-caused rotation in 6-OHDA-stimulated rats. Increased level of reduced glutathione content and a decreased level of MDA (malondialdehyde) were observed in the 6-OHDA rats post-treated with CAR. These findings suggest that CAR exerts protective effects, possibly related to an anti-oxidation mechanism, in these in vitro and in vivo models of Parkinson's disease.

Glioblastoma U-87MG tumour cells suppressed by ZnO folic acid-conjugated nanoparticles: an in vitro study.

Glioblastoma Multiform (GBM) known as the most common CNS malignant tumour. Therapy for GBM includes maximum tumour resection and chemotherapy. Recent advances have emphasized the use of nanoparticles, such as zinc oxide nanoparticles (ZnO-NPs). Conjugated ZnO NPs with folic acid (FA) easily pass through cell membrane. In the present study, ZnO NPs-FA applied to GBM U87MG cell line. ZnO NPs-FA synthesized according to the sol-gel method. The GBM U87MG and astrocytes 1321N1 cell lines cultured and divided into control, sham and ZnO NPs-FA groups. MTT assay used for the cell viability, and ROS assay and flow cytometry exploited. The size of nanoparticles was ≤20 nm using TEM and FTIR. After 12 hours, the viability for U87MG cells showed a significant decrease at 1.25 and 2.5 mg/ml concentrations. However, no such results obtained for astrocytes. According to the results, the ROS assay caused a significant increase in GBM cells at the mentioned concentration. It was concluded that dose-dependent conjugated NPs could play a therapeutic role in cancer therapy.

Simultaneous use of sensory stimulation and motor exercise improves the manual skills of educable children with mental retardation at preprimary and primary school levels.

Background: Children with mental retardation have various clinical problems. They mostly have motor delay and sensory deficit. Neurorehabilitation focuses on restoring remaining abilities. Thus, the present study was designed to study the effects of simultaneous use of sensory-motor therapy on manual skills of children with mental retardation. Methods: In this study, 120 educable boys and girls with mental retardation (9-12 years) were selected from 2 preprimary and primary exceptional centers in Tehran using stratified sampling method considering the geographical dispersion. The participants were divided into 2 equal trial and control groups using simple random sampling. Lincoln-Oseretsky Motor Development Scale, Purdue Pegboard test, and Handwriting Legibility Checklist of Persian Language were used. Simultaneous sensory stimulations and motor exercises were used for 3 one-hour weekly sessions for 12 consecutive weeks. Pre and posttests were done for evaluation. Using parametric paired and independent samples t tests, the findings were analyzed in SPSS 23. Results: The manual skills significantly improved following therapeutic use of simultaneous sensory stimulation and motor exercise (p=0.001). In the control group, the pre and post evaluation difference was not significant (p=0.813) Conclusion: Based on the findings of this study, simultaneous use of sensory-motor techniques can have better clinical results in the trial group compared to the control group. Thus, these types of techniques should be used more in clinics. However, further studies are needed for more comparison between separate applications of these techniques.

Coenzyme Q10 Influences on the Levels of TNF-α and IL-10 and the Ratio of Bax/Bcl2 in a Menopausal Rat Model Following Lumbar Spinal Cord Injury.

The roles of the immune response and apoptosis as potential mediators of secondary damage in spinal cord injury (SCI) are being investigated. Research is also being done to determine the effects of female gonadal steroids, which decrease during menopause, and antioxidants, such as coenzyme Q10 (CoQ10) on SCI. We hypothesized that in the absence of female gonadal steroids, which provide protection following an SCI, CoQ10 could modulate the expression of cytokines, such as tumor necrosis factor (TNF)-α and interleukin (IL)-10, besides aquaporin-4 (AQP4) water channels in the CNS, which participate in neuroinflammation, as well as the Bax and Bcl2 proteins that are involved in apoptosis at the site of injury. The spinal cord was compressed at the level of the T10 vertebrae and rats were treated by 10 mg/kg/day CoQ10 for 3 weeks after surgery. The TNF-α and IL-10 expressions were studied using an ELISA. Western blot was used to investigate the Bax/Bcl-2 ratio, AQP4. The level of TNF-α significantly decreased following the administration of CoQ10 compared with the level of IL-10. When the treatment group was compared with the OVX-SCI group, the ratio of Bax/Bcl2 significantly decreased in the groups (P < 0.01). Based on our findings, CoQ10 could be used to compensate for the absence of the neuroprotection effects provided by female gonadal steroids via reducing the inappropriate effects of the two main pathways of secondary damage in SCI apoptosis.

The adverse effects of the methoxsalen and ultraviolent A radiation on spermatogenesis in mice.

BACKGROUND: Different investigation showed that 5-methoxypsoralen and 8- methoxypsoralen reduce birth rates in the rats. OBJECTIVE: In this study we worked out the effect of methoxsalen together with ultraviolent A (UVA) radiation on mature Balb/C mice spermatogenesis. MATERIALS AND METHODS: The LD50 standard was determined 160 mg/kg and the UVA dose which causes erythema was calculated 0.046 J/cm2. A sub-lethal dose of 80 mg/kg of methoxsalen solution was injected intrapritoneally to mature mice and after one hour they were exposed to UVA radiation for 20 minutes. Experiments applied included methoxsalen alone, methoxsalen with UVA, UVA alone, sham group (a group received Tween 80), and control group (N=6). In all experimental groups except UVA alone group, injections were carried out, during two consecutive weeks. Serial cross sections (5 µm thickness) were prepared for morphological and histological studies. Tunica albuginea diameter, and number of type A and type B spermatogonia and histological investigation of the testes were measured. RESULTS: Microscopical and statistical analyses showed significant anomalies among the experimental groups compared to control and sham group. These anomalies included decrease the body weight; increase the relative testis weight; and decrease the number of spermapogonia (type A and B), primary spermatocytes, spermatids and sperms in experimental groups I and II compared to control group. Our results showed the number of spermatozoa in experimental group I was 22.6±2.12, in experimental group II was 33.6±2.05 and in control group was 44.3±2.77 (p<0.05). Moreover in some experimental groups (I and II) shrinkage of seminiferous tubules and release of primary spermatocyte and spermatids were observed to the lumen of them. CONCLUSION: It is concluded from the results of this work that treatment with methoxsalen with UVA can damage and disorganize seminiferous tubules and decrease spermatogenic cells.

The adverse effects of methoxsalen on the oogenesis of BALB/c mice.

OBJECTIVE: Methoxsalen is a natural photoactive compound which is found in many seed plants. A number of epidermal proliferative disorders can be treated by methoxsalen along with long wave ultraviolet A (UVA). MATERIALS AND METHODS: In an experimental study, we aimed to demonstrate the effect of methoxsalen, UVA and their combination on oogenesis Balb/C mice. There were two experimental groups and a control group. The experimental groups were composed of i. a short term group with treatment duration of 15 days and ii. a long term group with treatment duration of 5 weeks. Both the long term and short term experimental groups were further subdivided into a UVA group, a methoxsalen group and a methoxsalen plus UVA group. After treatment, mature females in prosterus phase of ovarian cycle were scarified with ether, while their ovaries were removed and prepared for histological studies. RESULTS: Both macro and microscopic studies showed significant anomalies (p<0.05) among experimental group ovaries as compared to control group. The obtained results showed a significant decrease in the following factors: number and diameter of corpus lutei, Graafian follicles, diameter of granulosa cell layer and oocytes, number of primordial and primary and growing follicles, while we observed an increase in number of atretic follicle. Furthermore, our findings confirmed an increase in theca diameter only through UVA treatment. Methoxsalen also reduced circulating estrogen levels in blood serum, significantly. Other cases of teratogenecity, such as follicles with three oocytes and disorganization in corpus luteum cells were observed. CONCLUSION: The result suggests that UVA, methoxsalen and their combination cause health problems and cell injuries.

Study of high glucose-induced apoptosis in PC12 cells: role of bax protein.

Hyperglycemia, which occurs under the diabetic condition, induces serious diabetic complications. Diabetic neuropathies, affecting the autonomic, sensory, and motor peripheral nervous system, are among the most frequent complications of diabetes. Little is known about the direct toxic effect of high glucose concentrations on neuronal cells. Therefore in the present study, glucose-induced toxicity was studied in PC12 cells as an in vitro cellular model for diabetic neuropathy using the MTT assay. The possible role of apoptosis was also investigated in this toxicity. The result showed that a 3-fold increase in optimum glucose concentration for PC12 cells (13.5 mg/ml) significantly reduced cell viability after 48 h. In Western blot analysis, the ratio of Bax/Bcl-2 protein expression in cells treated with high glucose was significantly increased compared to controls. Additionally high glucose could induce a DNA ladder pattern in PC12 cells, a hallmark of apoptosis indicating nuclear fragmentation. From our present results, it may be concluded that high glucose can cause PC12 cell death, in which apoptosis plays an important role possibly by the mitochondrial pathway through higher expression of Bax pro-apoptotic protein.