Unrestricted Hepatocyte Transduction with Adeno-Associated Virus Serotype 8 Vectors in Mice

ABSTRACT Recombinant adeno-associated virus (rAAV) vectors can mediate long-term stable transduction in various target tissues. However, with rAAV serotype 2 (rAAV2) vectors, liver transduction is confined to only a small portion of hepatocytes even after administration of extremely high vector doses. In order to investigate whether rAAV vectors of other serotypes exhibit similar restricted liver transduction, we performed a dose-response study by injecting mice with β-galactosidase-expressing rAAV1 and rAAV8 vectors via the portal vein. The rAAV1 vector showed a blunted dose-response similar to that of rAAV2 at high doses, while the rAAV8 vector dose-response remained unchanged at any dose and ultimately could transduce all the hepatocytes at a dose of 7.2 × 1012 vector genomes/mouse without toxicity. This indicates that all hepatocytes have the ability to process incoming single-stranded vector genomes into duplex DNA. A single tail vein injection of the rAAV8 vector was as efficient as portal vein injection at any dose. In addition, intravascular administration of the rAAV8 vector at a high dose transduced all the skeletal muscles throughout the body, including the diaphragm, the entire cardiac muscle, and substantial numbers of cells in the pancreas, smooth muscles, and brain. Thus, rAAV8 is a robust vector for gene transfer to the liver and provides a promising research tool for delivering genes to various target organs. In addition, the rAAV8 vector may offer a potential therapeutic agent for various diseases affecting nonhepatic tissues, but great caution is required for vector spillover and tight control of tissue-specific gene expression.

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High doses of prochlorperazine for cisplatin-induced emesis: A prospective, random, dose–response study

Cancer ◽

10.1002/1097-0142(19871101)60:9<2165::aid-cncr2820600908>3.0.co;2-c ◽

1987 ◽

Vol 60 (9) ◽

pp. 2165-2169 ◽

Cited By ~ 12

Author(s):

Brian I. Carr ◽

Douglas W. Blayney ◽

David A. Goldberg ◽

Patricia Braly ◽

Gerald E. Metter ◽

...

Keyword(s):

Dose Response ◽

High Doses ◽

Dose Response Study

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Dose-response study with high-dose inhaled salmeterol in healthy subjects.

British Journal of Clinical Pharmacology ◽

10.1111/j.1365-2125.1992.tb04049.x ◽

1992 ◽

Vol 33 (3) ◽

pp. 342-345 ◽

Cited By ~ 33

Author(s):

JG Maconochie ◽

JK Forster

Keyword(s):

Dose Response ◽

Healthy Subjects ◽

High Dose ◽

Dose Response Study

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Apparently Nonspecific Enzyme Elevations After Portal Vein Delivery of Recombinant Adeno-Associated Virus Serotype 2 Vector in Hepatitis C Virus-Infected Chimpanzees

Human Gene Therapy ◽

10.1089/hum.2007.174 ◽

2008 ◽

Vol 19 (7) ◽

pp. 681-689 ◽

Cited By ~ 5

Author(s):

Terence R. Flotte ◽

Jason Goetzmann ◽

James Caridi ◽

Joseph Paolillo ◽

Thomas J. Conlon ◽

...

Keyword(s):

Hepatitis C Virus ◽

Hepatitis C ◽

Portal Vein ◽

Adeno Associated Virus ◽

Virus Serotype

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A Limited Number of Transducible Hepatocytes Restricts a Wide-Range Linear Vector Dose Response in Recombinant Adeno-Associated Virus-Mediated Liver Transduction

Journal of Virology ◽

10.1128/jvi.76.22.11343-11349.2002 ◽

2002 ◽

Vol 76 (22) ◽

pp. 11343-11349 ◽

Cited By ~ 69

Author(s):

Hiroyuki Nakai ◽

Clare E. Thomas ◽

Theresa A. Storm ◽

Sally Fuess ◽

Sharon Powell ◽

...

Keyword(s):

Dose Response ◽

Transgene Expression ◽

Linear Increase ◽

Factor Ix ◽

Adeno Associated Virus ◽

Linear Dose ◽

Human Factor Ix ◽

Wide Range ◽

High Doses

ABSTRACT Recombinant adeno-associated virus (rAAV) vectors are promising vehicles for achieving stable liver transduction in vivo. However, the mechanisms of liver transduction are not fully understood, and furthermore, the relationships between rAAV dose and levels of transgene expression, total number of hepatocytes transduced, and proportion of integrated vector genomes have not been well established. To begin to elucidate the liver transduction dose response with rAAV vectors, we injected mice with two different human factor IX or Escherichia coli lacZ-expressing AAV serotype 2-based vectors at doses ranging between 4.0 × 108 and 1.1 × 1013 vector genomes (vg)/mouse, in three- to sixfold increments. A 2-log-range linear dose-response curve of transgene expression was obtained from 3.7 × 109 to 3.0 × 1011 vg/mouse. Vector doses above 3.0 × 1011 vg/mouse resulted in disproportionately smaller increases in both the number of transduced hepatocytes and levels of transgene expression, followed by saturation at doses above 1.8 × 1012 vg/mouse. In contrast, a linear increase in the number of vector genomes per hepatocyte was observed up to 1.8 × 1012 vg/mouse concomitantly with enhanced vector genome concatemerization, while the proportion of integrated vector genomes was independent of the vector dose. Thus, the mechanisms that restrict a wide-range linear dose response at high doses likely involve decreased functionality of vector genomes and restriction of transduction to fewer than 10% of total hepatocytes. Such information may be useful to determine appropriate vector doses for in vivo administration and provides further insights into the mechanisms of rAAV transduction in the liver.

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Decreased expression of the vitamin C transporter SVCT1 by ascorbic acid in a human intestinal epithelial cell line

British Journal Of Nutrition ◽

10.1079/bjn2001492 ◽

2002 ◽

Vol 87 (2) ◽

pp. 97-100 ◽

Cited By ~ 68

Author(s):

Lauren MacDonald ◽

Alfred E. Thumser ◽

Paul Sharp

Keyword(s):

Ascorbic Acid ◽

Vitamin C ◽

Cell Model ◽

Human Kidney ◽

The Body ◽

Epithelial Cell Line ◽

High Dose ◽

Acid Uptake ◽

Cellular Processes ◽

High Doses

Vitamin C (ascorbic acid) is an essential nutrient that is involved in a number of cellular processes. However, unlike most mammals, man is unable to synthesize vitamin C and it must therefore be acquired from the diet. Absorption of vitamin C is achieved by two transporters, SVCT1 and SVCT2, recently cloned from rat and human kidney. SVCT1 is thought to be the predominant transporter in the intestine. Vitamin C supplements are increasingly common, thus contributing to an increased dietary load, and therefore the aim of the present study was to investigate the effect of high doses of ascorbic acid on SVCT1 expression. Using the Caco-2 TC7 cell model of small intestinal enterocytes, we measured the effects of ascorbic acid (4·5 mg/ml culture medium) on L-[14C]ascorbic acid uptake and SVCT1 expression (determined by reverse transcription-polymerase chain reaction). Ascorbic acid uptake was decreased significantly in Caco-2 TC7 cells exposed to ascorbate for 24 h (-50 %, P<0·0005). Expression of SVCT1 was also significantly reduced by exposure to elevated levels of ascorbate for 24 h (-77 %, P<0·005). Taken together these results suggest that high-dose supplements might not be the most efficient way of increasing the body pool of vitamin C.

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The Effect of High Dose Vitamin C (ascorbic acid) on Proinflammatory Cytokines in COVID-19

Medical and Health Science Journal ◽

10.33086/mhsj.v5i1.1884 ◽

2021 ◽

Vol 5 (1) ◽

pp. 46-50

Author(s):

MD Ayu Mira Cyntia Dewi

Keyword(s):

Free Radicals ◽

Vitamin C ◽

Proinflammatory Cytokines ◽

Viral Infections ◽

Antiviral Drug ◽

The Body ◽

High Dose ◽

Literature Study ◽

Inflammatory Reactions ◽

High Doses

Background: COVID-19 is a new pandemic that has claimed many lives in many countries. This pandemic was caused by the SARSCoV2. Until now, there is no specific antiviral drug or vaccine against Covid-19 for potential therapy in humans. This virus can cause cytokine storms which can worsen symptoms in sufferers due to an imbalance between increased oxidant production and available antioxidants. Vitamin C is an important antioxidant that protects the body from various bad effects of free radicals. At high concentrations vitamin C plays an important role in immunomodulation. This study was conducted to determine the effect of high doses of vitamin C on levels of pro-inflammatory cytokines in Covid-19. Method: This research type is literature study. The population in this study were journals about Covid-19, vitamin C, antioxidants and free radicals, inflammatory reactions due to viral infections with samples taken from indexed journals published from 2015 to 2020. There are also clinical trials of high doses of vitamin C against inflammation in Covid-19 from these journals. Results: The results of the study in a clinical trial conducted on 54 patients enrolled in 3 hospitals given a 1: 1 ratio for high-dose intravenous vitamin C (HDIVC) or placebo administration. The HDIVC group received 12 g of vitamin C / 50 ml every 12 hours for 7 days at a rate of 12 ml / hour, and the placebo group received bacteriostatic water for injection in the same way. HDIVC administration showed a reduction in inflammatory markers compared to placebo. Conclusion: The conclusion of this study shows that high doses of vitamin C play a role in reducing levels of proinflammatory cytokines.

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Abstract WMP42: Astrocyte Specific rAAV-mediated Insulin-Like Growth Factor-1 Expression in Aging Female Rats Increases Post-Stroke Survival and Sensory Motor Performance

Stroke ◽

10.1161/str.47.suppl_1.wmp42 ◽

2016 ◽

Vol 47 (suppl_1) ◽

Author(s):

Andre K Okoreeh ◽

Shameena Bake ◽

Farida Sohrabji

Keyword(s):

Motor Performance ◽

Low Dose ◽

Female Rats ◽

Specific Gene ◽

High Dose ◽

Middle Aged ◽

Post Stroke ◽

Post Surgery ◽

Virus Serotype ◽

Sensory Motor

Background and Purpose: Our previous work shows that middle aged female rats sustain larger strokes as compared to younger female rats. With age, circulating and brain parenchymal levels of IGF-1 are reduced. Exogenous IGF-1 treatment improves infarct volume in aging females. Our recent studies show that astrocytes from aging females synthesize less IGF-1. Here we tested the hypothesis that elevation of astrocyte derived IGF-1 would improve stroke impairment in older female rats. Methods: Middle-aged (10-12 month old; acyclic) female rats were injected with adeno-associated virus serotype 5 (rAAV5) into the cortex and striatum. rAAV5 was packaged with the coding sequence of the IGF-1 gene downstream of an astrocyte-specific gene (GFAP). The construct contained the mCherry reporter gene. Control rAAV consisted of an identical shuttle vector construct without the IGF-1 gene. In separate experiments, two titers of virus were injected: high dose (5 X 10 12 VP/mL) or low dose (5 X 10 11 VP/mL). Three to four weeks after injection, middle-cerebral artery occlusion via an intraluminal suture for ninety minutes was performed followed by reperfusion. Post-surgery survival was monitored as well as sensory motor function using the vibrissae evoked forelimb placement task. Results: Specificity of IGF-1 expression was confirmed by visualization of the mCherry reporter under fluorescent illumination and immunohistochemistry. Post stroke survival was improved in animals that received the high dose rAAV-IGF-1 animals a 5-day period (p<0.001). Low dose rAAV-IGF-1 did not affect post stroke survival, however sensory motor performance was preserved in this group. In low dose control animals, ischemic stroke impaired performance on the vibrissae evoked forelimb placement task. Impairment was seen in the same-side and cross-midline task performance on the limb contralateral to the infarct and cross midline task on the limb ipsilateral to the infarcted side (p<0.05). No significant deficits were seen in the rAAV-IGF-1 low dose treated animals. Conclusion: These data support the hypothesis that increasing astrocytic IGF-1 in aging females improves post stroke survival and behavior outcomes.

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Ondansetron for the prevention of emesis induced by high-dose cisplatin. A multi-center dose-response study

Cancer ◽

10.1002/1097-0142(19900915)66:6<1101::aid-cncr2820660604>3.0.co;2-f ◽

1990 ◽

Vol 66 (6) ◽

pp. 1101-1105 ◽

Cited By ~ 20

Author(s):

Ali Khojasteh ◽

George Sartiano ◽

Efstathios Tapazoglou ◽

Eric Lester ◽

David Gandara ◽

...

Keyword(s):

Dose Response ◽

High Dose ◽

Dose Response Study

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PSII-18 Greater feed amounts during late gestation do not improve piglets birth weight: a dose-response study performed in gilts

Journal of Animal Science ◽

10.1093/jas/skz122.405 ◽

2019 ◽

Vol 97 (Supplement_2) ◽

pp. 230-231

Author(s):

Andre L Mallmann ◽

Elisar Camilotti ◽

Deivison Fagundes ◽

Carlos Vier ◽

Ana Paula Mellagi ◽

...

Keyword(s):

Body Weight ◽

Birth Weight ◽

Dose Response ◽

Feed Intake ◽

Feeding Strategy ◽

The Body ◽

Late Gestation ◽

Average Birth Weight ◽

Feeding Level ◽

Dose Response Study

Abstract In breeding farms, pork producers commonly use “bump feeding” as a feeding strategy. This technique consists of increasing daily feed amount on late gestation to improve piglets birth weight. A dose-response arrangement with 4 treatments (1.8, 2.3, 2.8, and 3.3 kg/d) was used to evaluate the effects on female reproductive performance and piglet birth weight. A total of 977 gilts were fed based on a corn-soybean meal diet from day 90 of gestation until farrowing. Gilts were weighed on days 90 and 112 of gestation and at weaning. Born alive and stillborn piglets were weighed within 12 h of birth. Colostrum yield and lactation feed intake were measured in a randomly selected sub-sample of 245 gilts. As expected, body weight gains were different at day 112 (P < 0.001) with the highest values observed in 3.3 kg/d treatment. As the feed amount increased during late gestation, greater were the body losses between d 112 and weaning (P < 0.001). Statistical tendencies for a quadratic effect of feeding level were observed for piglets born alive (P = 0.079), average birth weight of piglets (P = 0.083), and litter weight (P = 0.059). However, there were no differences among treatments on total born and mummified fetuses (P > 0.05). Gilts fed with lower feed amounts during late gestation had reduced stillborn percentages compared to those gilts fed with greater amounts. Colostrum yield and voluntary feed intake decreased linearly (P < 0.05) as the feed amount performed during late gestation increased. In conclusion, increasing the feed intake from day 90 of gestation until farrowing increased gilts body weight and stillborn rate, but reduced the colostrum yield and the lactation feed intake. In addition, there were no effects of the feeding level in late gestation on piglets birth weight.

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