34 research outputs found
NEUROPROTECTIVE EFFECT OF ARTOCARPUS LAKOOCHA EXTRACT AND OXYRESVERATROL AGAINST HYDROGEN PEROXIDE-INDUCED TOXICITY IN SH-SY5Y CELLS
Objective: Artocarpus lakoocha Roxb. is a traditional medical plant native to Southeast Asia and used as a dried aqueous extract so-called puag haad. Its role (and its major ingredient, oxyresveratrol) as an antioxidant neuroprotectant were explored.Methods: Differentiated SH-SY5Y neuroblastoma cells in 96-well plates were challenged with 200 µM H2O2 for 4 h and either Trolox (100 µM), oxyresveratrol (5-100 µM), or puag haad (1.2-25 µg/ml) applied 2 h before H2O2 or for 20 h after H2O2 washout. Cell viability, mitochondrial function, intracellular ROS, and lipid peroxidation were assessed.Results: Continuous presence of both H2O2 and antioxidant reduced mitochondrial function by ~50% but only by 30% with antioxidant. Sustained 24 h H2O2 showed no recoveries with antioxidants. Cell viability was modestly restored when antioxidants accompanied H2O2 for 4 h and both washed for another 20 h, but little recovery of mitochondrial function even though antioxidants removed ROS and prevent lipid peroxidation. Antioxidants added for 20 h after H2O2 marginally improve mitochondria and modestly restore cell viability, but lipid peroxidation was completely reversed.Conclusion: These results show that mitochondrial protection was illusive, yet both tested compounds, puag haad and oxyresveratrol, improved cell viability and especially ROS levels and lipid peroxidation. The potency oxyresveratrol on the redox-sensitive expression of antioxidant enzymes and its pharmacokinetics suggests that oral puag haad could provide effective protection in transient neurodegenerative disease.Â
A Bird\u27s-Eye View of the Multiple Biochemical Mechanisms that Propel Pathology of Alzheimer\u27s Disease: Recent Advances and Mechanistic Perspectives on How to Halt the Disease Progression Targeting Multiple Pathways.
Neurons consume the highest amount of oxygen, depend on oxidative metabolism for energy, and survive for the lifetime of an individual. Therefore, neurons are vulnerable to death caused by oxidative-stress, accumulation of damaged and dysfunctional proteins and organelles. There is an exponential increase in the number of patients diagnosed with neurodegenerative diseases such as Alzheimer’s (AD) as the number of elderly increases exponentially. Development of AD pathology is a complex phenomenon characterized by neuronal death, accumulation of extracellular amyloid-β plaques and neurofibrillary tangles, and most importantly loss of memory and cognition. These pathologies are most likely caused by mechanisms including oxidative stress, mitochondrial dysfunction/stress, accumulation of misfolded proteins, and defective organelles due to impaired proteasome and autophagy mechanisms. Currently, there are no effective treatments to halt the progression of this disease. In order to treat this complex disease with multiple biochemical pathways involved, a complex treatment regimen targeting different mechanisms should be investigated. Furthermore, as AD is a progressive disease-causing morbidity over many years, any chemo-modulator for treatment must be used over long period of time. Therefore, treatments must be safe and non-interfering with other processes. Ideally, a treatment like medicinal food or a supplement that can be taken regularly without any side effect capable of reducing oxidative stress, stabilizing mitochondria, activating autophagy or proteasome, and increasing energy levels of neurons would be the best solution. This review summarizes progress in research on different mechanisms of AD development and some of the potential therapeutic development strategies targeting the aforementioned pathologies
Derris Scandens Benth Extract Radiosensitizes HT-29 Colon Cancer Cells
Objective: To evaluate the radiosensitizing potential of Derris scandens extract in a human colon cancer cell model.
Methods: The radiosensitizing effect of D., scandens extract on human colon cancer cells (HT-29) and non-cancerous human retinal epithelial cells (RPE) was determined by cell survival and micronuclei analysis after irradiation. Cell cycle distribution was analyzed by a flow cytometer.
Results: D. scandens extract powerfully increases the radiosensitivity of HT-29 cells, but is less toxic and does not affect the radiosensitivity of RPE cells. Furthermore, the extract was found to reduce radiation-induced G2/M phase arrest in HT-29 cells, but not in RPE cells.
Conclusion: D., scandens extract may have potential as a radiosensitizer for cancer treatment
Spirogyra neglecta inhibits the absorption and synthesis of cholesterol in vitro
Background: Spirogyra neglecta (SN) has many nutritional benefits and it is commonly used to ameliorate different human conditions including inflammation, gastric ulcer, hyperglycemia, and hyperlipidemia. However, the mechanism of the hypocholesterolemic effect of SN still remains unclear. Therefore, the present study was aimed to evaluate the effect of SN extract particularly on cholesterol absorption and synthesis mechanisms.
Methods: For cholesterol absorption, the uptake of cholesterol was measured by using tritium radiolabeling of cholesterol in Caco-2 cells. Bile acid binding, micelles size, and cholesterol solubility were analyzed in in vitro assays, while cholesterol synthesis was evaluated by using a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase assay kit.
Results: SN extract was found to decrease cholesterol uptake in Caco-2 cells and decreased the solubility of cholesterol in micelles. The SN extract bound to taurocholate, taurodeoxycholate, and glycodeoxycholate bile acids, and increased micelles size. SN has also demonstrated an inhibitory effect on HMG-CoA reductase (HMGR) enzymatic activity. For further experimentation, the treatment combination of SN and ezetimibe (0.04Â mg/mL) showed a greater significant reduction in cholesterol uptake than the extract alone.
Conclusion: These observations suggested that inhibitory cholesterol absorption effects of SN could be mediated through the modulation of size and solubility of cholesterol micelles, resulting in interference of cholesterol uptake. In addition, SN inhibited the rate limiting step of cholesterol synthesis. This study provides supporting evidence for the potential usage of SN as a cholesterol lowering agent
Protective effect of silk lutein on ultraviolet B-irradiated human keratinocytes
Carotenoids are efficient antioxidants that are of great importance for human health. Lutein and zeaxanthin are carotinoids present in high concentrations in the human retina which are involved in the photoprotection of the human eye. Lutein may also protect the skin from ultraviolet (UV)-induced damage. The present study investigated the protective effect of lutein extracted from yellow silk cocoons of Bombyx mori on human keratinocytes against UVB irradiation. A human keratinocyte cell line and primary human keratinocytes were used to investigate the UVB protection effects of silk lutein and plant lutein. Silk lutein showed no cytotoxicity to keratinocytes. Treatment with silk lutein prior to UVB irradiation enhanced cell viability and cell proliferation, and reduced cell apoptosis. The protective effects of silk lutein may be superior to those of plant lutein. Silk lutein may have a benefit for protection of keratinocytes against UVB-irradiation
Effects of silk sericin on the proliferation and apoptosis of colon cancer cells
Sericin is a silk protein woven from silkworm cocoons (Bombyx mori). In animal model, sericin has been reported to have anti-tumoral action against colon cancer. The mechanisms underlying the activity of sericin against cancer cells are not fully understood. The present study investigated the effects of sericin on human colorectal cancer SW480 cells compared to normal colonic mucosal FHC cells. Since the size of the sericin protein may be important for its activity, two ranges of molecular weight were tested. Sericin was found to decrease SW480 and FHC cell viability. The small sericin had higher anti-proliferative effects than that of the large sericin in both cell types. Increased apoptosis of SW480 cells is associated with increased caspase-3 activity and decreased Bcl-2 expression. The anti-proliferative effect of sericin was accompanied by cell cycle arrest at the S phase. Thus, sericin reduced SW480 cell viability by inducing cell apoptosis via caspase-3 activation and down-regulation of Bcl-2 expression. The present study provides scientific data that support the protective effect of silk sericin against cancer cells of the colon and suggests that this protein may have significant health benefits and could potentially be developed as a dietary supplement for colon cancer prevention
The effect of dietary sericin on rats
ABSTRACT: Dietary proteins have been reported to be beneficial for lipid metabolism, tissue growth, development, and repair, as well as immune response. The interactions of dietary proteins and their digested products may regulate the physiology and metabolism of the gastrointestinal tract. However, proteins are largely digested before reaching the large intestine. The present study investigated the use of the non-dietary protein, silk sericin, in rats. Rats were fed either with casein or sericin proteins. Their body weight, food consumption, and complete blood count were measured. The results showed that during the experimental periods, rats fed with casein and sericin diets had no significant changes on body weight, food consumption, or complete blood count. Sericin-fed rats had a significantly decreased CD8a and CD80 positive cells when compared with standard casein protein. In conclusion, dietary proteins may have a differential impact on the leukocyte profile. The mechanisms underlying these changes are not clear but they might be due to the different amino acid compositions of the proteins studied
Potential of Coffee Fruit Extract and Quinic Acid on Adipogenesis and Lipolysis in 3T3-L1 Adipocytes
This study was to assess the impact of different colors of coffee fruit (green, yellow and red) on adipogenesis and/or lipolysis using 3T3-L1 adipocytes. Characterization of chemical onstituents in different colors of coffee fruit extracts was determined by ESI-Q-TOF-MS. The cytotoxicity of the extracts in 3T3-L1 preadipocytes were evaluated by MTT assay. Oil-red O staining and amount of glycerol released in 3T3-L1 adipocytes were measured for lipid accumulation and lipolysis activity. All coffee fruit extracts displayed similar chromatographic profiles by chlorogenic acid > caffeoylquinic acid > caffeic acid. Different colors of raw coffee fruit possessed inhibitory adipogenesis activity in 3T3-L1 adipocytes, especially CRD decreased lipid accumulation approximately 47%. Furthermore, all extracts except CYF and their major compounds (malic, quinic, and chlorogenic acid) increased glycerol release. Our data suggest that different colors of coffee fruit extract have possessed anti-adipogenic and lipolytic properties and may contribute to the anti-obesity effects