Biomedical subjects

Michelle Tucci

Publications and source records attributed to Michelle Tucci.

At least 37 records · Page 2Linked to original sources

PubMed2006

The physiological effect of conventional treatment with epigallocatechin-3-gallate, thymoquinone, and tannic acid on the LNCaP cell line.

Antioxidants are substances that function to protect cells from damage caused by unstable free radicals, which are responsible for damage that may lead to cancer. (Blot et al., 1993). Several antioxidants have been discussed for use in prevention and treatment of prostate carcinoma. Epidemiological evidence has indicated that these antioxidants may reduce the risk of prostate cancer by underlying mechanisms that remain unclear. The LNCaP cell line was introduced by inoculation from a supraclavicular lymph node metastasis of human prostate cancer (Horoszewicz et al., 1983). The aim of this study was to use the androgen-dependent LNCaP human prostate cancer cell line as a cell model to evaluate the physiological effects to conventional treatments with both low (LD) and high doses (HD) of epigallocatechin-3-gallate (EGCG), thymoquinone (TQ), and tannic acid (TA). Following treatment, cells were incubated and the various groups were evaluated at 24, 48, and 72 hours. After 24, 48, and 72 hours of incubation, all treated cells caused a reduction in cell growth, but the TQHD treated group seemed to be the most potent. The TQHD group also demonstrated the greatest decrease in total protein levels in comparison to the control. According to one-way analysis of variance (ANOVA), significant differences were observed (P < 0.001). Upon observation of the prostatic specific antigen (PSA) values, all groups showed decreased levels; however, the TQHD treated group showed an initial suppression after 24 hours and then finally adapted to treatment after 48 and 72 hours. Malondialdehyde (MDA) values were also assessed at the same three time periods (24, 48, and 72 hours) as an indicator of membrane integrity. After 24 hours of incubation, the TAHD group demonstrated the greatest increase in MDA levels. Morphologically, the cells demonstrated significant changes, such as swelling and irregularity in appearance upon antioxidant exposure. These findings reveal that antioxidants may serve as agents for prostate cancer prevention by providing safer and effective treatments for prostate cancer; however, further experiments are needed to understand the interactions involved.

Antineoplastic Agents↗

PubMed2006

Effects of (-)epigallocatechin gallate and thymoquinone on proliferation of a PANC-1 cell line in culture.

The limited ability of current treatments for pancreatic cancer prompted us to examine the effects of antioxidants on proliferation of pancreatic cancer cells. Antioxidants have been reported to possess antioxidant activity in vitro. The specific aim of this study was to investigate the role of epigallocatechin gallate (EGCG), a major component of green tea and thymoquinone on the proliferation and viability of PANC-1 cell line using a standard method of treatment. The PANC-1 cells were treated with three predetermined doses of thymoquinone and EGCG (5, 25, and 50 ug/dL) for 24, 48, and 72 hours in culture medium. Determination of viability and morphology was examined microscopically after each 24 hour interval. Data collected from this study indicated a dose dependent relationship with direct administration of EGCG alone or in combination with thymoquinone. However, a rebound effect was observed after 48 and 72 hours during direct administration of both antioxidants. These results indicate that direct administration of EGCG alone or in combination with thymoquinone can limit PANC-1 cell proliferation (p < 0.05). EGCG and thymoquinone may be a potent biologic inhibitor of human pancreatic carcinomas, reducing their propagation activities.

Adenocarcinoma↗

PubMed2006

Hep-2 cellular function following either a bolus administration or continuous sustained release of IP-6.

Inositol 6-phosphate (IP-6) has demonstrated novel anti-cancer activity using several different tumor models. IP-6, or phytic acid, has antioxidant properties that directly act to inhibit cancer cell growth. In previous experiments using Hep-2 cells treated with a single treatment dose of IP-6 (1 mM) showed decreases in number only after 72 hours. The goal of this experiment was to deliver IP-6 in a sustained continuous manner for periods of 24, 48 and 72 hours to Hep-2 cancer cells and compare the changes in cell growth and morphology after a single bolus dose of IP-6. Our results indicated that IP-6 administered as a bolus dose was unable to reduce Hep-2 cell numbers after 24 hours. By 48 and 72 hours an approximate 50% increase in cell numbers were seen in the single dose treatment group. Sustained delivery of IP-6 resulted in significant reduction of cells over 48 hours. The dose of IP-6 given (1 mM) did not induce changes in cellular protein concentrations nor increase cellular membrane damage. Morphologically, the Hep-2 cell appear small, round to cuboidal in shape with dark eccentric nuclei and scant cytoplasm. After treatment with 1 mM IP-6, the cells showed evidence of degeneration with irregular cell borders and hyperchromatic nuclei. Overall, 1 mM IP-6 was unable to reduce Hep-2 cell proliferation for periods greater than 48 hours; however, further evaluation of the Hep-2 cytology revealed significant cellular degenerative changes that warrant additional studies to understand the action of IP-6.

Antineoplastic Agents↗

PubMed2006

Evaluation of bioflavonoids as potential chemotherapeutic agents.

Bioflavonoids are compounds that are natural plant antioxidants. Antioxidants have been shown to prevent damage caused by free radicals to DNA and other molecules. Bioflavonoids have demonstrated several cancer preventive properties. In addition to antioxidant activity, these compounds may reduce abnormal cell growth and inflammation; help the body get rid of cancer-causing agents; and restore communication between different cells in the body. The objective of this study is to compare nontoxic phenols as cancer chemotherapeutic, agents and to apply these agents in treating human cancers. In this study the effects of a single dose of 10 microM Green Tea Extract (EGCG), 5 microM Tannic Acid (TA), or 5 microM Thymoquinone (TQ) on Hep-2 cells were determined. Compounds were evaluated in their effectiveness to reduce cell number. The cells were also evaluated for membrane damage, and alterations in cellular morphology after 24, 48, and 72 hours in culture. The results showed a 50% reduction in Hep-2 cell numbers after 24 hours in TQ treated cells. After 48 hours, the cells treated with TQ and TA exhibited a four-fold decrease in total cell number compared to the control and EGCG treated cells. Cell numbers were similar in all treatment groups by 72 hours. At 48 hours the only significant increase in cell damage was seen in cells treated with EGCG. The results indicated that naturally occurring bioflavonoids given in a bolus dose could alter cellular viability. It appears the drug is either utilized by the cells or chemically degraded in the media leading to increased cell numbers back toward control values with time in culture. In order for the compounds to be effective chemotherapeutic agents, the data also suggests a need for continuous administration over bolus dosing.

Antineoplastic Agents↗

PubMed2006

Targeted sustained delivery of tobramycin at the site of a femoral osteotomy.

Complex fractures are difficult to manage because of the increased risk of secondary infection. Traditional treatments include debridment and local administration of antibiotics. Local antibiotic therapy is a safe technique resulting in high local concentration of antibiotics with minimal systemic levels. Local antibiotics effectively control infection in animal models. The length of implantation and the need for removal of the delivery vehicle places the patient at risk for additional surgical procedure as well as delays the fixation procedure. Development of a bioresorbable carrier that can deposit therapeutic concentrations of antibiotics locally without side-effects will provide positive outcomes for the patient. Tricalcium phosphate lysine (TCPL) ceramic capsules containing tobramycin were implanted at the site of a femoral osteotomy delivered therapeutic concentrations of the drug locally and reduced the incidence of infection compared to TCPL capsule which were uncharged by 50%. In addition, the ceramic material was osteoconductive and animals in TCPL + TOB and TCPL carrier alone showed evidence of osteoblast alkaline phosphatase activity for a period of 15 weeks. Neither the carrier nor the carrier containing antibiotics displayed untoward effects on body weight, vital organs and reproductive organs over a 15 week period. The results from this study demonstrated that TCPL can be used as an effective osteoconductive material capable of delivering therapeutic concentrations of antibiotics over 15 week period.

Animals↗

PubMed2005

Evaluation of the male reproductive organs after treatment with continuous sustained delivery of statin for fracture healing.

The 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) are widely used for the treatment of hyperlipidemia, and recent in vitro and animal data suggest that statins promote bone formation and increase bone strength. We examined the relationship between sustained continuous delivery of statin and fracture healing rates in adult male animals with femoral segmental fractures. Because statin affects the production of cholesterol we also evaluated the influence of statin, on adrenal and testicular steroidogenesis and the morphology of the reproductive tract tissues in animals receiving statin for a period of 12 weeks post surgery. Simvastatin significantly increased fracture healing and without significant influence on the body weights and the weights of the reproductive organs. Basal plasma LH, FSH and testosterone levels were not affected by active treatment with simvastatin. Reproductive tissue morphology was unchanged by local sustained release of statin. In conclusion, long-term simvastatin treatment delivered at a fracture target site did not influence testicular reproductive and endocrine function, but was able to effectively heal complicated segmental fracture.

Animals↗

PubMed2005

The role of route of estrogen adminstration on the proliferation of SiHa cells in culture.

The specific objectives of this investigation were: (1) to evaluate the effect of estrogen on SiHa cervical cells delivered by TCPL delivery system versus conventional administration as a model for cervical cancer intervention and (2) to determine the estrogen dose effect on proliferation of these cells in culture. Estrogen was delivered for three time periods, 24, 48, and 72 hours both by conventional administration (direct administration) and drug delivery system using TCPL ceramic capsules. Three dosages of estrogen were selected (2, 10, and 100 pg/mL). Ceramic capsules were prepared using standard procedures (release profile 2, 10 or 100 pg/mL). Capsules were gas sterilized prior to being placed in the wells with cells. Data collected from this study indicated that, regardless of the route of administration, estrogen exposure did not induce major cellular injury at the 24 and 48 hour time period. Initially, there were various responses to estrogen among all groups compared to control. At 72 hours phase all experimental groups induced greater proliferation rate in the conventional delivery than in the groups exposed to sustained estrogen delivery. Low and medium doses conventionally added to the cells resulted in a decrease in cell number at 48 hours phase compared to the initial response at the 24 hours phase. With medium and high sustained delivery of estrogen rates, the data revealed that proliferation rate is directly proportional to duration of delivery compared to conventional means. The data suggest that the route of administration of estrogen is an instrumental tool in the prognosis of cervical cancer.

Antineoplastic Agents↗

PubMed2005

Glomerular response to adrenocortical hormone alone or in combination with selenomethionine.

Increased levels of glucocorticoids (GC) can result in major complications such hypertension and vascular injury. Chronically, this condition may lead to impairment of renal function. Glucocorticoid excess was considered the etiologic agent that triggers over production of reactive oxygen species (ROS). The mode of action of ROS was implicated to disrupt nitric oxide availability in the vascular endothelium, leading to vascular complications. To circumvent this damage attempts were made to use antioxidants in order to counter-balance the oxidative process. The objectives of this study were: (1) to establish an animal model of increased glucocorticoid levels by sustained delivery and (2) to determine if sustained delivery of selenomethionine in combination with glucocorticoids could protect kidney tubular structures using adult rats. Sixteen female rats were divided into four equal groups (control and 3 experimental groups implanted with tricalcium phosphate lysine drug delivery systems (TCPL) charged with either 50mg selenomethionine (Se), 50 mg corticosterone (C), or 50 mg of both C and Se). At the end of 24 days, the rats were sacrificed and both kidneys were removed for histopathological analysis. Quantitative analysis was performed on serum calcium levels, body weights and kidney weights in animals from all groups. Kidney slides were screened for possible structural damage. Sustained release of Se and Se+C resulted in a significant reduction of glomerular area (p < 0.05). Data obtained indicated that C, Se and Se+C administration caused a reduction in serum calcium levels compared to control animals. The reduction may be in part to changes in calcium-filtered load, changes in glomerular filtration rates or interference of calcium absorption from the gut. In conclusion, data obtained from this investigation provided the literature with significant information regarding the role of sustained delivery of supraphysiological levels of corticosterone in modifying kidney structure and function (possibly alter blood pressure).

Adrenal Cortex Hormones↗

PubMed2005

Sustained release of OP-1 and antibiotics in treatment of femoral defects in male rats.

Osteogenic proteins (OP-1) promote osteoinduction. Formation of new bone growth in patients receiving OP-1 is not consistent, and is possibly due to the short half-life of the drug. In order to test the capacity of OP-1 to consistently produce bone in a fracture model, a drug delivery system was developed to prolong the action of OP-1. Fifteen Sprague Dawley male rats were randomly divided into three equal groups; Animals in group 1 served as control. Animals in groups 2 and 3 had a 5mm defect created in the left femur using a number six dental burr and a drug delivery capsule (TCPL) containing either antibiotic alone (sham) or antibiotic +OP-1. Body weights, blood, and X-rays were taken weekly. Femurs and organs were harvested 30 days post-op, and processed for histomorphometry. Data was analyzed using ANOVA and significant difference between the groups was determined using Student Newman Kuels (p < 0.05). The results showed complete bone healing in the OP-1 group with an evident callus formation. The osteoid tissue exhibited a proliferation of osteoblasts, which differentiated from the vascularized mesenchymal tissue. The complete bone healing using OP-1 sharply contrasted sham treatment, where an obvious injury was still seen at 30 days. Histologically sham animals exhibited the early stage of repair with evidence of blood clotting and mesenchyme with early formation of osteoblasts. Overall, OP-1 delivered in a sustained manner for 30 days caused increased bone formation in a defect model.

Animals↗

PubMed2005

Stimulation of fracture healing by continuous delivery of demineralized bone matrix proteins and tobramycin.

Demineralized bone matrix (DBM) is an allogenous, bioabsorbable material that has long been used for its osteoinductive and osteoconductive properties. A significant complication experienced by physicians who perform bone defect filling surgery is the risk of subsequent bacterial infections and the inefficiency of oral antibiotics to provide adequate prophylaxis against microorganisms, especially Staphylococcus aureus, Pseudomonas aeruginosa, and Staphylococcus epidermidis. In order to deliver both DBM and an efficient antiobiotic at high local concentrations without deleterious systemic effects, a ceramic sustained delivery system was implanted and monitored over the course of 30 days for bone regeneration, infection, and systemic effects. Twenty-five adult Sprague Dawley albino male rats were used in the experiment. They were randomly divided into five equal groups. Animals in group 1 were used as control, group 2 animals had a created 5mm defect, in group 3 defect induced and implanted with devices loaded with antibiotic (tobramycin) alone, group 4 had a created defect plus DBM, and group 5 had a created defect, plus tobramycin (which is effective against the aforementioned organisms) and DBM. At 30 days post-implantation, the experimental animals showed no significant difference in weight when compared to the control and sham animals. X-rays taken at this time showed the experimental femurs to be totally healed and virtually indistinguishable from control. Initial dissections revealed that the implants were accepted by the hosts as shown by the fibrous, vascularized sheath that surrounded the femurs and capsules. The implants were found to be in close contact with the cancellous bone and none of the sheaths showed signs of infection. Macroscopically, no defect could be detected in the experimental animals, while little regeneration was observed in the femurs of the sham animals.

Animals↗

PubMed2005

The effect of agonists and antagonists on Hep-2 cells.

Androgens may play an important role in promoting the growth of laryngeal carcinomas. The aims of this investigation were to investigate the effects of (testosterone (T) and androstendione (AED)) in the presence of the anti-androgen, spironolactone (S), n Hep-2 cellular proliferation and damage after 24, 48 and 72 hours. Hep-2 cells were divided into six groups (n = 5) control, S, T, AED, S+T, and S+AED, respectively. The cells were harvested after each incubation period into two different fractions: suspended cells and adhered cells. Cell counts and cellular damage determinations were performed on each fraction. Analysis of variance was used to determine significance at p < 0.05. Data for cell counts revealed an interesting phenomenon between the two fractions. Adhered cells showed decreased cell numbers in the presence of S and T for 24 - 48 hours followed by a significant increase at 72 hours. Cells in the adhered fraction incubated in the presence of AED or AED + S were significantly lower for the duration of the experiment. However AED or AED + S treatment caused significant increase in cell number in suspended fraction for the duration of the experiment. All treatments after 72 hours showed a slight reduction in MDA levels indicating treatments did not cause cell damage. Overall, the data suggests the possibility of two populations of cells that respond differently to the AED. T had no significant effect on either cell fraction for the first 48 hours followed by a significant increase in cell number at 72 hours suggesting T may need to be converted enzymatically to the more potent androgen, dihydrotestosterone.

Androstenedione↗

PubMed2005

The role of proteoglycans in idiopathic carpal tunnel syndrome.

Decompression of the carpal canal is the most common hand surgery performed in the United States. Hand surgeons perform 460,000 carpal tunnel releases (CTR) each year, which cost the medical industry in excess of two billion dollars per year. The focus of this investigation was to identify the changes, which occur in the flexor tenosynovium of patients undergoing CTR at the connective tissue level. The connective tissues determine the amount and arrangement of macromolecules (fibers, proteoglycans, and glycoproteins) in the extracellular matrix. The proteoglycans are soluble macromolecules that have both structural and metabolic roles. Glycoproteins help to form the interstitial space, basement membrane and function as cell surface receptors. The mechanical function of the proteoglycans includes stabilization of the collagen fibers as well as function in the hydration of the tissues. It has been previous shown that changes in the oxygen concentration at the tissue level can alter the proteoglycans profile of the tissue. During periods of hypoxia, such as those obtained during repetitive motion CTS; the glycolytic pathway acts as the energy source for the tissue. Productions of chondroitin sulfates are a process consumes NAD and would be potentially toxic to the cells under anaerobic conditions. Production of keratan sulfate is NAD sparing product, and may act as a survival pathway for cells under adverse conditions. The disruption in the proteoglycan balance will allow for alterations in the ECM and changes in hydration status of the tissues may have serious implication in CTS because the carpal canal is anatomically very narrow and increases in volume within the canal can result in further compression of the nerve. Flexor tenosyioum was obtained from patients undergoing CTR and compared with control tissue for dermatan, keratan and chondroitin sulfate. The results show a greater density of keratan reactivity in CTS tissues identified by immunostaining. In addition to changes in proteoglycan content there was also an increase in new vessel formation in the CTS tissues. The data obtained suggests that the shifts in the proteoglycan ratios may render the tissues less able to withstand the compressive forces and therefore allow for more force to be placed on the median nerve within the carpal canal.

Carpal Tunnel Syndrome↗

PubMed2005

The effects of genistein concentrations on Hep-2 cellular function.

Genistein is a phytoestrogen that has shown potential as a chemotherapeutic agent, which acts by inhibiting protein-tyrosine kinase and topoisomerase II enzymes. These particular enzymes are crucial for cellular proliferation. The goal of this study was to evaluate the effect of genistein concentration (0.5, 0.05 or 0.005 mg/mL) on Hep-2 cells functional capacity. Specifically, to evaluate cellular number, protein, damage and morphology at 24, 48, and 72 hours phases. Data obtained from this study revealed that cell numbers were significantly reduced in low and medium concentrations after 24hrs, and cell numbers appeared to rebound at 48 and 72hrs in an inverse fashion. This data suggests continuous administration of the drug at therapeutic levels would serve as a better chemotherapeutic agent. Cellular damage was not evidenced and suggesting that the drug did not target the cellular membrane site. Morphological changes such as anucleation were seen at 24 hrs in all doses suggesting that genistein targets the genome directly. Interestingly, cellular function was able to recover in the lower doses of genistein treatment indicating cellular metabolism of the drug. Also, this information suggests that genistein mode of action by targeting enzymatic activity, as opposed to causing alterations within the cellular membrane, leading to leakage of cellular contents and ultimately cellular death since the membrane did not show evidence of lipid peroxidation.

Antineoplastic Agents↗

PubMed2005

Growth and cell viability of estradiol and IP-6 treated Hep-2 laryngeal carcinoma cells.

Inositol 6-phosphate (IP-6) has demonstrated novel anti-cancer activity using several different tumor models. IP-6, a phytoestrogen, has estrogen receptor (ER) binding capabilities that are not known to cause cellular proliferation in hormone sensitive cells. It is hypothesized that IP6 can induce competitive inhibition with estrogen for estrogenic binding sites on cancer cells resulting in decreased proliferation. In this experiment, Hep-2 cells were treated with Estradiol and IP-6 in a dose dependant manner for 24, 48, and 72 hours. They were analyzed for changes in number, protein concentrations, damage, and morphology. There was an increase in cell proliferation in Estradiol treated Hep-2 cells. Cells treated with IP-6 showed no change in cell proliferation in the 24 or 48-hour groups, but there was a decrease in number with the 72-hour group, particularly with the 1mM dose. Both the Estradiol and IP-6 treatments caused no membrane oxidation and the level of protein synthesis stayed consistent. The morphology showed small round to cuboidal, single cells with scant, dense, basophilic cytoplasm and hyperchromatic nuclei with smooth borders. Some cells showed anucleation and cellular degeneration. Although IP-6 is a phytoestrogen, the results show that affinity for estrogen binding sites on Hep-2 cells is greatly decreased. However, with time given increased concentrations, IP-6 can cause a decrease in the cellular proliferation of Hep-2 cells without initiating cellular apoptosis.

Antineoplastic Agents↗

PubMed2005

The effects of isolated antioxidants from black seed on the cellular metabolism of A549 cells.

UNLABELLED: Reactive oxygen species cause cytotoxic effects. The body requires the uptake of exogenous compounds with antioxidant potential. Black seed (BS) is a plant that contains at least one active lipid soluble antioxidant, thymoquinone. Fractionation of the seed components yielded antioxidant compounds in both the water soluble and lipid soluble fractions. The objective of the study was to determine the safety of the fractionated compounds and compare their potency with pure thymoquinone and vitamin E on A549 cells in culture for 24, 48 and 72 hours. RESULTS: Black seed extracts and pure thymoquinone showed markedly reduced levels of MDA for the duration of the study. The vitamin E dosage used led to greater toxicity and cellular damage rather than cell protection. Cellular proteins levels after 24 hours showed cells in BS + ETOH extract group had the highest metabolic activity. However, at 72 hours, the activity was shifted and showed the least amount of protein synthesis. As for vitamin E, the results were consistent throughout all three phases showing slow metabolic activity. Cell number was decreased after 24 hours in thymoquinone treated cells, and remained reduced for the duration of the study. The BS+H2O fraction showed a similar trend to thymoquinone, where as the BS+ETOH fraction showed a negative shift in cell number at 48 hours when compared with the control. CONCLUSION: The study concludes that of the two BS extracts, the BS+H2O extract had the greatest effect on the cell viability and function.

Adenocarcinoma↗

PubMed2005

Evaluation of insulin-like growth factor-1 and parathyroid hormone on growth characteristics of MG-63 cells.

Insulin-like Growth Factor-1 (IGF-1) and Parathyroid hormones (PTH) are major endocrine secretions that contribute to bone formation. The purpose of this experiment was to examine MG-63 bone like cells after treatment with PTH and IGF-1 in low (1 ug), medium (5 ug), and high (50 ug) dosage levels. MG-63 cells were plated onto a 24 well tissue culture plate at a density of 1 x 1--5 cells per well. The experiment was designed to evaluate cell counts, cell damage (MDA), protein levels, calcium levels, alkaline phosphatase levels, and cellular morphology after 24, 48, and 72 hours post incubation with IGF-1 and PTH. Both hormones stimulated cellular mitotic division as evidenced by morphology and cell numbers. There was an inverse relationship between dose and cell number with the lower dose of IGF-1 and PTH causing the most increase. In both hormones, the exposure to the highest dose induced the largest MDA level increase. However, in the protein levels, few changes in protein levels were found with IGF-1, but PTH showed an increase of protein levels over the time periods. Morphological evaluation showed prominent nucleoli and cellular division throughout both treatments, however the cells with IGF-1 became extremely elongated and the cells with PTH became rather plump. The information gathered suggests that IGF-1 and PTH have an anabolic effect on MG-63 and the effect is dose dependent with both treatments with the lower dose being more effective.

Cell Differentiation↗

PubMed2005

Pathophysiological response of rhesus monkey kidney epithelial cells exposed to epigallocatechin-3-gallate.

Green tea extracts are obtained from Camellia sinensus leaves that have been dried and contain the polyphenol known as catechins (epigallocatechin-3-gallate, EGCG). Green tea has been suggested to have an inhibitory effect on various complications such as HIV, cancer cells, homocysteine-related diseases, and cardiovascular disease. The literature is lacking on the role that green tea might have on normal cells that are at a high risk of irreversible injury. These cells include the lining of vessels (endothelium) and kidney tubules (epithelium). The specific objective of this study was to investigate the effects of various concentrations of green tea on the proliferation and viability of Rhesus Monkey Kidney epithelial cells (RMKEC) in culture. Thirty tubes were pre-plated with RMKEC sub-divided into six equal groups. In-groups 1-5, tubes were treated with 20, 2, 0.2, and 0.002i M of active extract of green tea (EGOG), respectively. Data obtained suggests that: (1) at 24 hour phase, exposure to 20, 2, and 0.0.2 microM concentrations induced cell proliferation and no significance difference was observed using 0.002 microM EGCG in comparison to the control, (2) at 48 hour phase, the use of 20 uM EGCG induced a proliferative effect in comparison to the control, (3) a decrease in cell proliferation was observed using a concentration of 2, 0.2, 0.002 microMEGCG in comparison to the control, (4) at 72 hour phase, there was a decrease in cell number in the groups treated with 20 and 2 microM concentrations of EGCG, (5) at 96 hour phase, there was a decrease in cell number in the group treated with the 0.002 microM concentration of EGOG, (6) RMK EC treated with EGCG at concentration of 0.2i M for 24, 48, 72, and 96 hours displayed a significant decrease in catalase, and MDA, (7) RMKEC treated with 0.002 for 48, 72, and 96 ours displayed an increase in MDA and catalase. The various concentrations of green tea affected Rhesus Monkey Kidney Epithelial cell growth, function, and viability; however, the data suggests that further studies need to be conducted to determine the full impact of green tea on Kidney Epithelial function.

Animals↗

PubMed2005

The effect of conventional and sustained delivery of levodopa on SH-SY5Y neuroblastoma cells.

UNLABELLED: L-dihydroxyphenylalanine-(L-dopa) has been used for the treatment of Parkinson's disease for decades. Recently it has been shown that L-dopa, at concentrations of 0.25 x 10(4) M or larger, can be toxic for human neuroblastoma cells. Toxicity has been associated with the productions of high levels of quinones. The reactive oxygen or nitrogen species generated in the enzymatical oxidation or auto-oxidation of an excess amount of dopamine or L-dopa induce neuronal damage and/or apoptotic or non-apoptotic cell death. The objective of this study was to investigate if the delivery method could reduce the toxicity associated with higher levels of L-dopa. SH-SY5Y neuroblastoma cells were challenged with a bolus administration of 5, 50, 100 or 500 microM of L-dopa or a sustained delivery of L-dopa to release the desired concentrations by the end of one incubation period. The cells were incubated for periods of 24, 48 or 72 hours, and at the end of each phase cell number, cell morphology, and cellular glutathione levels were determined. Conventional administration of L-dopa showed reductions in cell number at 72 hours in cells treated with 50 and 500 microM L-dopa. A similar trend was observed using drug delivery administration of L-dopa. Glutathione levels were reduced in the treatment groups after 24 hours and showed recovery by 48 hours. Morphologic evaluation revealed that the lower dose groups appeared similar to control in both conventional and drug delivery whereas cellular distortion was observed at higher doses regardless of delivery method. CONCLUSION: Lower dose L-dopa was demonstrated to be less cytotoxic in SH-SY5Y neuroblastoma cells in both conventional and sustained drug delivery methods.

Antiparkinson Agents↗