80 research outputs found
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
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
Arthroscopic Mumford procedure utilizing the anteromedial and Neviaser portals – a pilot cadaveric study on neurovascular structures at risk
Introduction: Degenerative disorder involving the acromio-clavicular joint (ACJ) is quite common especially in the elderly. One of the surgical modalities of treatment of this disorder is the Mumford Procedure. Arthroscopic approach is preferred due to its reduced morbidity and faster post-operative recovery. One method utilizes the anteromedial and Neviaser portals, which allow direct and better visualization of the ACJ from the subacromial space. However, the dangers that may arise from incision and insertion of instruments through these portals are not fully understood. This cadaveric study was carried out to investigate the dangers that can arise from utilization of these portals and which structures are at risk during this procedure. Methods: Arthroscopic Mumford procedures were performed on 5 cadaver shoulders by a single surgeon utilizing the anteromedial and Neviaser portals. After marking each portals with methylene blue, dissection of nearby structures were carried out immediately after each procedure was completed. Important structures (subclavian artery as well as brachial plexus and its branches) were identified and the nearest measurements were made from each portal edges to these structures. Results: The anteromedial portal was noted to be closest to the suprascapular nerve (SSN) at 2.91 cm, while the Neviaser portal was noted to be closest also to the SSN at 1.60 cm. The suprascapular nerve was the structure most at risk during the Mumford procedure. The anteromedial portal was noted to be the most risky portal to utilize compared to the Neviaser portal. Conclusion: Extra precaution needs to be given to the anteromedial portal while performing an arthroscopic distal clavicle resection in view of the risk of injuring the suprascapular nerve of the affected limb
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
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
Nutritional Composition, in vitro Antioxidant Activity and Artemia salina L. Lethality of Pulp and Seed of Tamarindus indica L. Extracts
This study was designed to examine the nutritional composition, antioxidant activity
and medium lethal concentration (LC50 value) of Tamarindus indica L. pulp and seed
extracts in vitro. The extraction was set at 40°C, 60°C and 100°C for 12 hours, 6 hours
and 15 minutes respectively to determine the optimum extraction parameter whereas
the anti-oxidant activity of the extracts was measured using iron (III) reduction (FRAP)
assay. Total phenolic content (TPC) of the extracts was estimated as gallic acid
equivalent by Folin-Ciocalteau method. Toxicity potential of the extract was assessed
in vitro by Artemia salina lethality test both in seed and pulp samples. The results showed
that tamarind seed contained a higher percentage of carbohydrate, protein, fat and
energy (15%, 82%, 95% and 33.13% respectively) than the pulp. On the other hand, the
pulp demonstrated a high moisture (51.1%) and ash (34.84%) content than the seed. For
the mineral analysis, tamarind seed contained higher Ca and C (1.0% and 50.73%
respectively) than the pulp (0.27% and 40.40% respectively). No heavy metals were
detected in both samples. Seed extracted at 60°C/6 hours and 100°C/15 minutes showed
the highest TPC value and were significantly different (p<0.05) than the seed extracted
at 40°C/12 hours. Anti-oxidant activity is positively correlated to the TPC value of the
extracts (R=0.991). The pulp and seed extracted at 100°C/15 minutes showed the highest
FRAP value among its groups (216.17 ± 14.06 μmol (Fe)/g and 659.74 ± 16.40 μmol (Fe)/
g respectively). This study indicates that tamarind pulp and seed extracts possess
beneficial antioxidant properties and the optimum extraction parameter is 100°C for 15
minutes. In Artemia salina lethality test, tamarind pulp caused significant mortality of
the crustacean larvae with LC50 in the range of 26-28 μL/mL. Tamarind seed were not
toxic to Artemia salina since the LC50 of the extracts was higher than 1000 μL/mL
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
Anatomical variations of median nerve formation, distribution and possible communication with other nerves in preserved human cadavers
Formation, distribution and possible communication of the median nerve are essential to know in treatment and surgeries of various conditions of injuries e.g. repair or reconstruction of the median nerve post traumatic accident. In the present study, 44 upper limbs were dissected. Root forming the median nerve, the median nerve in relation with the axillary artery and communication of the median nerve with other nerves were noted
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
Antidepressant-like effect of aqueous extract of Channa striatus fillet in mice models of depression.
Background and Objectives: Channa (C.) striatus (Malay-Haruan), is a fresh water snakehead fish, consumed as a rejuvenating diet in post-parturition period in local Malay population. The aqueous extract of C. striatus fillet (AECSF) was reported to act through serotonergic receptor system in a previous study. There is no scientific report on neuropharmacological effects of C. striatus. Based on these data, the antidepressant-like effect of C. striatus was evaluated in mice models of depression. Materials and Methods: AECSF was prepared by steaming the fillets as described previously. Antidepressant activity was studied in male ICR mice using forced swimming test (FST) and tail suspension test (TST). Open-field test was used to evaluate any psychomotor stimulant activity. AECSF was administered intraperitoneally at the concentrations of 30%, 40% and 50% w/v at the dosage of 10 ml/kg. Amitriptyline (10 mg/kg) was used as positive control. Results: All the three concentrations of AECSF (30%, 40% and 50% w/v) significantly reduced the immobility time (p < 0.001) in FST and TST. All the three concentrations of AECSF (30%, 40% and 50% w/v) significantly (p < 0.001) reduced locomotor activity in a dose-dependent manner in open-field test. Conclusions: AECSF produced significant reduction of immobility time in both FST and TST. Amitriptyline produced a significant reduction of immobility time in both FST and TST similar to previous findings. The AECSF produced a dose-dependent decrease in locomotor activity in the open-field test. This hypolocomotion effect indicated the absence of any psychomotor stimulant activity thereby supporting the antidepressant-like effect of the AECSF. The pharmacological mechanisms of the observed antidepressant-like effect and hypolocomotion effect are not understood from our study. Hence, further studies are required
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