An inhibited dopamine synthesizing cell model of AADC deficiency

Introduction: Aromatic L-amino acid decarboxylase deficiency (AADC) is a rare autosomal recessive pediatric neurotransmitter disease. To date it remains poorly understood mainly due to an absence of a disease model. The dopaminergic neuroblastoma cell SH-SY5Y was chosen to develop our AADC deficiency model. These cells are not native dopamine synthesizers. Objective: To develop a dopamine-producing cellular model of AADC deficiency using SH-SY5Y neuroblastoma cells. Methods: Dopamine pathway proteins were identified with Western Blotting. Dopaminergic differentiation was attempted using all-trans retinoic acid (ATRA) with dopamine detection via HPLC-ECD post alumina extraction. Treatment with L-DOPA provided SH-SY5Y with excess precursor. RT-PCR was used to determine the expression of markers of mature neurons. Results: Western Blot screening identified AADC, dopamine β-hydroxylase and tyrosine hyrdoxylase proteins, indicative of a dopaminergic pathway. ATRA was unsuccessful in producing dopamine from the cells. L-DOPA treatment however, generated dopamine first visible as a HPLC-ECD peak 30 minutes post-incubation. Prior to this, SH-SY5Y dopamine synthesis from L-DOPA has never been documented. This de novo synthesis is then inhibited using benserazide to form our AADC deficiency cell model. RT-PCR showed that SH-SY5Y cells express markers of mature neurons in its ‘native’ state and is not affected by L-DOPA and benserazide treatment. This cell model will potentially benefit many areas of AADC deficiency research. Conclusion: SH-SY5Y cells produced HPLC-ECD measureable amounts of dopamine with the addition of L-DOPA. Our model of AADC deficiency is generated by quelling the dopamine production with Benserazide

Effects of mitragynine from Mitragyna speciosa Korth leaves on working memory

Aim of the study: Mitragyna speciosa Korth from Rubiaceae family is a tropical plant indigenous to Southeast Asia particularly in Thailand, Peninsular of Malaysia and Indonesia. The leaves have been used by natives for their opium-like effect and cocaine-like stimulant ability to combat fatigue and enhance tolerance to hard work. However there is no scientific information about the effect of mitragynine on the cognitive performances. This study is designed to examine the working memory effects of mitragynine which is extracted from Mitragyna speciosa mature leaves. Materials and methods: The cognitive effect was studied using object location task and the motor activity in open-field test. Mitragynine 5, 10 and 15. mg/kg and were administered by intraperitoneal (IP) for 28 consecutive days and evaluated on day 28 after the last dose treatment. Scopolamine was used as the control positive drug. Results: In this study there is prominent effects on horizontal locomotor activity was observed. Mitragynine significantly reduced locomotor activity in open-field test compared with vehicle. In object location task mitragynine (5, 10 and 15. mg/kg) did not showed any significances discrimination between the object that had changed position than the object that had remain in a constant position. Conclusion: Our results suggest that chronic administration of mitragynine can altered the cognitive behavioral function in mic

Toxoplasma gondii stimulates the behavioural changes of rodents: updated evidence

In recent years, there have been an increased number of reports in the literatures on animal behavioural changes linked with intracellular protozoan Toxoplasma gondii. Evidence for animal behavioural changes with Toxoplasma gondii infection comes from experimental tests on animal models such as mice and rats. These studies describe the important mechanisms of behavioural changes which involving neuromodulator and neurotransmitter level. Furthermore, behavioural changes also have been identified in human as well as animal models that may also play a role in development of schizophrenia in humans

Delta-9-tetrahydrocannabinol (∆9-THC) induce neurogenesis and improve cognitive performances of male Sprague Dawley rats

Neurogenesis is influenced by various external factors such as enriched environments. Some researchers had postulated that neurogenesis has contributed to the hippocampal learning and memory. This project was designed to observe the effect of Delta-9-tetrahydrocannabinol (∆9-THC) in cognitive performance that influenced by the neurogenesis. Different doses of ∆9-THC were used for observing the neurogenesis mechanism occurs in the hippocampus of rats. The brains were stained with antibodies, namely BrdU, glial fibrillary acidic protein (GFAP), nestin, doublecortin (DCX) and class III β-tubulin (TuJ-1). The cognitive test was used novel-object discrimination test (NOD) while the proteins involved, DCX and brain-derived neurotrophic factor (BDNF), were measured. Throughout this study, ∆9-THC enhanced the markers involved in all stages of neurogenesis mechanism. Simultaneously, the cognitive behaviour of rat also showed improvement in learning and memory functions observed in behavioural test and molecular perspective. Administration of ∆9-THC was observed to enhance the neurogenesis in the brain, especially in hippocampus thus improved the cognitive function of rats

Antidepressant-like effects of omega-3 fatty acids in postpartum model of depression in rats

Postpartum depression (PPD) is a psychiatric disorder that occurs in 10–15% of childbearing women. It is hypothesized that omega-3 fatty acids, which are components of fish oil, may attenuate depression symptoms. In order to examine this hypothesis, the animal model of postpartum depression was established in the present study. Ovariectomized female rats underwent hormone-simulated pregnancy (HSP) regimen and received progesterone and estradiol benzoate or vehicle for 23 days, mimicking the actual rat's pregnancy. The days after hormone termination were considered as the postpartum period. Forced feeding of menhaden fish oil, as a source of omega-3, with three doses of 1, 3, and 9 g/kg/d, fluoxetine 15 mg/kg/d, and distilled water 2 ml/d per rat started in five postpartum-induced and one vehicle group on postpartum day 1 and continued for 15 consecutive days. On postpartum day 15, all groups were tested in the forced swimming test (FST) and open field test (OFT), followed by a biochemical assay. Results showed that the postpartum-induced rats not treated with menhaden fish oil, exhibited an increase in immobility time seen in FST, hippocampal concentration of corticosterone and plasmatic level of corticosterone, and pro-inflammatory cytokines. These depression-related effects were attenuated by supplementation of menhaden fish oil with doses of 3 and 9 g/kg. Moreover, results of rats supplemented with menhaden fish oil were comparable to rats treated with the clinically effective antidepressant, fluoxetine. Taken together, these results suggest that menhaden fish oil, rich in omega-3, exerts beneficial effect on postpartum depression and decreases the biomarkers related to depression such as corticosterone and pro-inflammatory cytokines

High brain

Mitragyna speciosa or locally known as ketum in Malaysia is traditionally popular in the northern parts of Peninsular Malaysia and Thailand. The leaves are chewed or boiled and taken daily as a popular tonic by farmers to endure the sun, fatigue, and hard work. The truth is that ketum cheats the brain into believing that you are stronger than you thought

D-galactose and aluminium chloride induced rat model with cognitive impairments

Cognitive impairments and cholinergic dysfunctions have been well reported in old age disorders including Alzheimer’s disease (AD). d-galactose (D-gal) has been reported as a senescence agent while aluminium act as a neurotoxic metal, but little is known about their combined effects at different doses. The aim of this study was to establish an animal model with cognitive impairments by comparing the effects of different doses of co-administrated D-gal and aluminium chloride (AlCl3). In this study male albino wistar rats were administered with D-gal 60 mg/kg.bwt intra peritoneally (I.P) injected and AlCl3 (100, 200, or 300 mg/kg.bwt.) was orally administered once daily for 10 consecutive weeks. Performance of the rats were evaluated through behavioural assessments; Morris water maze (MWM) and open field tests (OFT); histopathological examination was performed on the hippocampus; moreover biochemical measurements of acetylcholinesterase (AChE) and hyperphosphorylated tau protein (p-tau) were examined. The results of this experiment on rats treated with D-gal 60 + AlCl3 200 mg/kg.bwt showed near ideal cognitive impairments. The rats exhibited an obvious memory and learning deficits, marked neuronal loss in hippocampus, showed increase in AChE activities and high expression of p-tau within the tissues of the brain. This study concludes that D-gal 60 + AlCl3 200 mg/kg.bwt as the ideal dose for mimicking AD like cognitive impairments in albino wistar rats. It is also crucial to understand the pathogenesis of this neurodegenerative disease and for drug discovery

Phytochemical screening and antioxidant activities of Erythroxylum cuneatum leaf extracts

Objectives: Erythroxylum cuneatum is a plant that belongs to the family of Erythroxylaceae. It is locally known as “Chinta mula” and found around Southeast Asia. This study identified the active phytochemicals and antioxidant properties in various extracts derived from dried leaves of Erythroxylum cuneatum. Methods: The tests of phytochemical screening included extracts of ethanol, acetone, hexane and aqueous. The antioxidant activity was determined by measuring total phenolic content, 2,2- diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and hydrogen peroxide scavenging activity. Results: The phytochemical screening of Erythroxylum cuneatum dried leaves revealed the presence of phenolic compounds namely flavonoids, tannins and total phenols. Alkaloids and saponins were also detected. The antioxidant activity of the examined extracts varies depending on the solvent used. Generally, acetone extract showed highest total phenolic content with a value of 2228 µg GAE/g and highest DPPH radical scavenging activity with IC50 of 1020.00 µg/ml compared to the standard ascorbic acid of 304.44 µg/ml. Ethanol extract exhibited high hydrogen peroxide activity with IC50 of 83.09 µg/ml. Conclusion: This study showed that acetone extract contains highest phenolic compounds and both ethanol and acetone extracts are a potential source of natural antioxidants

Antidepressant-like effect of methanolic extract of Punica granatum (pomegranate) in mice model of depression

Punica granatum L. (pomegranate) is commonly known for its traditional use as a food supplement and for its medicinal values. P. granatum methanolic pulp and peel extract were investigated for its antidepressant activities on mice model of depression using tail suspension test (TST) and forced swimming test (FST). P. granatum pulp and peel extract were administered at doses of 25 and 50 mg/kg intraperitoneally, respectively while fluoxetine (20 mg/kg) was administered intraperitoneally as the standard drug. The results showed that P. granatum pulp extract at 25 mg/kg significantly exhibited antidepressant activity in both TST and FST which able to reduce the immobility time, similar to fluoxetine, a recognized antidepressant drug. It is concluded that P. granatum methanolic extract has the ability as antidepressant-like agent. Further research is required to investigate the exact pharmacological mechanism of action of this fruit

Graphene oxide loaded with protocatechuic acid and chlorogenic acid dual drug nanodelivery system for human hepatocellular carcinoma therapeutic application

Hepatocellular carcinoma or hepatoma is a primary malignant neoplasm that responsible for 75–90% of all liver cancer in humans. Nanotechnology introduced the dual drug nanodelivery method as one of the initiatives in nanomedicine for cancer therapy. Graphene oxide (GO) loaded with protocatechuic acid (PCA) and chlorogenic acid (CA) have shown some anticancer activities in both passive and active targeting. The physicochemical characterizations for nanocomposites were conducted. Cell cytotoxicity assay and lactate dehydrogenase were conducted to estimate cell cytotoxicity and the severity of cell damage. Next, nanocomposite intracellular drug uptake was analyzed using a transmission electron microscope. The accumulation and localization of fluorescent-labelled nanocomposite in the human hepatocellular carcinoma (HepG2) cells were analyzed using a fluorescent microscope. Subsequently, Annexin V- fluorescein isothiocyanate (FITC)/propidium iodide analysis showed that nanocomposites induced late apoptosis in HepG2 cells. Cell cycle arrest was ascertained at the G2/M phase. There was the depolarization of mitochondrial membrane potential and an upregulation of reactive oxygen species when HepG2 cells were induced by nanocomposites. In conclusion, HepG2 cells treated with a graphene oxide–polyethylene glycol (GOP)–PCA/CA–FA dual drug nanocomposite exhibited significant anticancer activities with less toxicity compared to pristine protocatechuic acid, chlorogenic acid and GOP–PCA/CA nanocomposite, may be due to the utilization of a folic acid-targeting nanodrug delivery system