Quercetin glycosides induced neuroprotection by changes in the gene expression in a cellular model of Parkinson's disease

Quercetin glycosides, rutin and isoquercitrin, are potent antioxidants that have been found to possess neuroprotective effect in diseases like Parkinson's and Alzheimer's disease. In the present study, we have examined the gene expression changes with rutin and isoquercitrin pretreatment on 6-hydroxydopamine (6-OHDA)-treated toxicity in rat pheochromocytoma (PC12) cells. PC12 cells were pretreated with rutin or isoquercitrin and subsequently exposed to 6-OHDA. Rutin-pretreated PC12 attenuated the Park2, Park5, Park7, Casp3, and Casp7 genes which were expressed significantly in the 6-OHDA-treated PC12 cells. Rutin upregulated the TH gene which is important in dopamine biosynthesis, but isoquercitrin pretreatment did not affect the expression of this gene. Both rutin and isoquercitrin pretreatments upregulated the ion transport and antiapoptotic genes (NSF and Opa1). The qPCR array data were further validated by qRT-PCR using four primers, Park5, Park7, Casp3, and TH. This finding suggests that changes in the expression levels of transcripts encoded by genes that participate in ubiquitin pathway and dopamine biosynthesis may be involved in Parkinson's disease

Current concepts of neurodegenerative mechanisms in Alzheimer's disease

Neurodegenerative diseases are hereditary or sporadic conditions that result in the progressive loss of the structure and function of neurons as well as neuronal death. Although a range of diseases lie under this umbrella term, Alzheimer's disease (AD) and Parkinson's disease (PD) are the most common neurodegenerative diseases that affect a large population around the globe. Alzheimer's disease is characterized by the abnormal accumulation of extracellular amyloid-beta plaques and intraneuronal neurofibrillary tangles in brain regions and manifests as a type of dementia in aged individuals that results in memory loss, multiple cognitive abnormalities, and intellectual disabilities that interfere with quality of life. Since the discovery of AD, a wealth of new information has emerged that delineates the causes, mechanisms of disease, and potential therapeutic agents, but an effective remedy to cure the diseases has not been identified yet. This could be because of the complexity of the disease process, as it involves various contributing factors that include environmental factors and genetic predispositions. This review summarizes the current understanding on neurodegenerative mechanisms that lead to the emergence of the pathology of AD

Saccharomyces cerevisiae kinetochore protein (rDsn1p) induced apoptosis in Chinese hamster ovary cells

Dsn1p is a member of the MIND complex that forms part of the yeast kinetochore, which is essential for the proper chromosomal segregation during cell division. Its functionality is gene dosage dependent and it has characteristics of haploinsufficiency. Bioinformatics alignments predicted the existence of nuclear homologues in higher eukaryotic organisms. Literature on the possibility of Dsn1p being a functional homologue of these organisms is scarce. In this study we employed recombinant DNA expression technology to explore whether Dsn1p can function in a mammalian cell line, Chinese Hamster Ovary (CHO). Expression of rDsn1p in CHO cells induced cytopathic effects including changes in cellular morphology and cell size. Inhibition of cell growth was observed at the beginning the fourth post-transfection week. The recombinant CHO cell culture showed cytotoxic effects following the accumulation of the Dsn1p, resulting in apoptotic cell death; as evidenced by the presence of nuclear fragmentation and surface blebbing in the dying cells. This suggests that rDsn1p may interact with the counterpart/ligand of the nuclear homologue of this protein in CHO cells, resulting in nuclear anomalies and inhibition of cell growth, as observed in our previous study using yeast cells

Tocotrienols ameliorate neurodegeneration and motor deficits in the 6-ohda-induced rat model of parkinsonism: Behavioural and immunohistochemistry analysis

Parkinson’s disease (PD) is a debilitating neurodegenerative disease, which progresses over time, causing pathological depigmentation of the substantia nigra (SN) in the midbrain due to loss of dopaminergic neurons. Emerging studies revealed the promising effects of some nutrient compounds in reducing the risk of PD. One such nutrient compound that possess neuroprotective effects and prevents neurodegeneration is tocotrienol (T3), a vitamin E family member. In the present study, a single dose intracisternal injection of 250 µg 6-hydroxydopamine (6-OHDA) was used to induce parkinsonism in male Sprague Dawley (SD) rats. Forty-eight hours post injection, the SD rats were orally supplemented with alpha (α)-and gamma (γ)-T3 for 28 days. The neuroprotective effects of α-and γ-T3 were evaluated using behavioural studies and immunohistochemistry (IHC). The findings from this study revealed that supplementation of α-and γ-T3 was able to ameliorate the motor deficits induced by 6-OHDA and improve the neuronal functions by reducing inflammation, reversing the neuronal degradation, and preventing further reduction of dopaminergic neurons in the SN and striatum (STR) fibre density

Protective effect of aqueous extract from Spirulina platensis against cell death induced by free radicals

<p>Abstract</p> <p>Background</p> <p><it>Spirulina </it>is a commercial alga well known to contain various antioxidants, especially phycocyanin. Apart from being sold as a nutraceutical, <it>Spirulina </it>is incorporated as a functional ingredient in food products and beverages. Most of the previous reports on antioxidant activity of <it>Spirulina </it>were based on chemical rather than cell-based assays. The primary objective of this study was to assess the antioxidant activity of aqueous extract from <it>Spirulina </it>based on its protective effect against cell death induced by free radicals.</p> <p>Methods</p> <p>The antioxidant activity of the cold water extract from food-grade <it>Spirulina platensis </it>was assessed using both chemical and cell-based assays. In the cell-based assay, mouse fibroblast cells (3T3) cells were incubated for 1 h in medium containing aqueous extract of <it>Spirulina </it>or vitamin C (positive control) at 25, 125 and 250 μg/mL before the addition of 50 μM 1,1-diphenyl-2-picrylhydrazyl (DPPH) or 3-ethylbenzothiazoline-6-sulfonic acid (ABTS). The cells were incubated for another 24 h before being assessed for cell death due to apoptosis using the Cell Death Detection ELISA Kit. Spectrophotometric assays based on DPPH and ABTS were also used to assess the antioxidant activity of the extract compared to vitamin C and vitamin E (positive controls).</p> <p>Results</p> <p><it>Spirulina </it>extract did not cause cytotoxic effect on 3T3 cells within the range of concentrations tested (0 - 250 μg/mL). The extract reduced significantly (p < 0.05) apoptotic cell death due to DPPH and ABTS by 4 to 5-fold although the activity was less than vitamin C. Based on the DPPH assay, the radical scavenging activity of the extract was higher than phycocyanin and was at least 50% of vitamin C and vitamin E. Based on the ABTS assay, the antioxidant activity of the extract at 50 μmug/mL was as good as vitamin C and vitamin E.</p> <p>Conclusions</p> <p>The results showed that aqueous extract of <it>Spirulina </it>has a protective effect against apoptotic cell death due to free radicals. The potential application of incorporating <it>Spirulina </it>into food products and beverages to enhance their antioxidant capacity is worth exploring.</p

Compatibility of the Omnican (R) Pen Needles with Insulin Pens, Humapen (R) and Novopen (R)

This study was carried out to assess accuracy of Omnican (R) insulin pen needles (29G and 30G) by measuring the weight of insulin delivered in each of 10 depressions of the plunger comparing these using other pen-injectors (Humapen (R) and Novopen (R) for each gauge. We found that the needle-to-needle variation was not statistically significant when the needles were used to dispense insulin using either of the insulin pens (Humapen (R) and Novopen (R). HumaPen (R) insulin pen was found to deliver the insulin closer to set target volume using either gauge (29G and 30G) of the Omnican (R) needles in some of the insulin ranges used in this study

Unravelling the neuroprotective mechanisms of carotenes in differentiated human neural cells: biochemical and proteomic approaches

Carotenoids, fat-soluble pigments found ubiquitously in plants and fruits, have been reported to exert significant neuroprotective effects against free radicals. However, the neuroprotective effects of total mixed carotenes complex (TMC) derived from virgin crude palm oil have not been studied extensively. Therefore, the present study was designed to establish the neuroprotective role of TMC on differentiated human neural cells against 6-hydroxydopamine (6-OHDA)-induced cytotoxicity. The human neural cells were differentiated using retinoic acid for six days. Then, the differentiated neural cells were pre-treated for 24 hr with TMC before exposure to 6-OHDA. TMC pre-treated neurons showed significant alleviation of 6-OHDA-induced cytotoxicity as evidenced by enhanced activity of the superoxide dismutase (SOD) and catalase (CAT) enzymes. Furthermore, TMC elevated the levels of intra-neuronal dopamine and tyrosine hydroxylase (TH) in differentiated neural cells. The 6-OHDA induced overexpression of α-synuclein was significantly hindered in neural cells pre-treated with TMC. In proteomic analysis, TMC altered the expression of ribosomal proteins, α/β isotypes of tubulins, protein disulphide isomerases (PDI) and heat shock proteins (HSP) in differentiated human neural cells. The natural palm phytonutrient TMC is a potent antioxidant with significant neuroprotective effects against free radical-induced oxidative stress

Supplementation with Natural Forms of Vitamin E Augments Antigen-Specific TH1-Type Immune Response to Tetanus Toxoid

This study compared the ability of three forms of vitamin E [tocotrienol-rich fraction (TRF), alpha-tocopherol ( -T), and deltatocotrienol ( -T3)] to enhance immune response to tetanus toxoid (TT) immunisation in a mouse model. Twenty BALB/c mice were divided into four groups of five mice each. The mice were fed with the different forms of vitamin E (1 mg) or vehicle daily for two weeks before they were given the TT vaccine [4 Lf] intramuscularly (i.m.). Booster vaccinations were given on days 28 and 42. Serum was collected (days 0, 28, and 56) to quantify anti-TT levels. At autopsy, splenocytes harvested were cultured with TT or mitogens. The production of anti-TT antibodies was augmented ( &lt; 0.05) in mice that were fed with -T3 or TRF compared to controls. The production of IFN-and IL-4 by splenocytes from the vitamin E treated mice was significantly ( &lt; 0.05) higher than that from controls. The IFN-production was the highest in animals supplemented with -T3 followed by TRF and finally -T. Production of TNF-was suppressed in the vitamin E treated group compared to vehicle-supplemented controls. Supplementation with -T3 or TRF can enhance immune response to TT immunisation and production of cytokines that promote cell-mediated (TH1) immune response

Effects of supplementation with tocotrienol-rich fraction on immune response to tetanus toxoid immunization in normal healthy volunteers

Background/Objectives: Vitamin E is an essential fat-soluble vitamin that has been shown to induce favorable effects on animal and human immune systems. The objective of this study was to assess the effects of tocotrienol-rich fraction (TRF) supplementation on immune response following tetanus toxoid (TT) vaccine challenge in healthy female volunteers. Subjects/Methods: In this double-blinded, placebo-controlled clinical trial, participants were randomly assigned to receive either placebo (control group) or 400 mg of TRF (study group) supplementation daily. Over the 2-month period of the study, volunteers were asked to attend three clinical sessions (that is, on days 0, 28 and 56) and blood samples were obtained from the volunteers during the follow-up. On day 28, all volunteers were also vaccinated with the TT vaccine (20 Lf) intramuscularly. Results: The results from the clinical trial showed that TRF supplementation significantly increased the total vitamin E level in the plasma of the TRF-supplemented volunteers compared with the placebo group, indicating overall compliance. Volunteers supplemented with TRF showed a significantly (P0.05) enhanced production of interferon-γ and interleukin (IL)-4 by the mitogen or TT-stimulated leukocytes compared with the control group. Volunteers from the TRF group produced significantly (P < 0.05) lower amounts of IL-6 compared with the placebo group. Anti-TT IgG production was also significantly (P < 0.05) augmented in the TRF-supplemented group compared with the placebo group. Conclusions: We conclude that TRF has immunostimulatory effects and potential clinical benefits to enhance immune response to vaccines