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1.
Fish Physiol Biochem ; 48(1): 145-159, 2022 Feb.
Article En | MEDLINE | ID: mdl-35034221

Many metabolic diseases in fish are often associated with lowered mitochondrial fatty acid ß-oxidation (FAO). However, the physiological role of mitochondrial FAO in lipid metabolism has not been verified in many carnivorous fish species, for example in largemouth bass (Micropterus salmonids). In the present study, a specific mitochondrial FAO inhibitor, mildronate (MD), was used to investigate the effects of impaired mitochondrial FAO on growth performance, health status, and lipid metabolism of largemouth bass. The results showed that the dietary MD treatment significantly suppressed growth performance and caused heavy lipid accumulation, especially neutral lipid, in the liver. The MD-treated fish exhibited lower monounsaturated fatty acid and higher long-chain polyunsaturated fatty acids in the muscle. The MD treatment downregulated the gene expressions in lipolysis and lipogenesis, as well as the expressions of the genes and some key proteins in FAO without enhancing peroxisomal FAO. Additionally, the MD-treated fish had lower serum aspartate aminotransferase activity and lower pro-inflammation- and apoptosis-related genes in the liver. Taken together, MD treatment markedly induced lipid accumulation via depressing lipid catabolism. Our findings reveal the pivotal roles of mitochondrial FAO in maintaining health and lipid homeostasis in largemouth bass and could be hopeful in understanding metabolic diseases in farmed carnivorous fish.


Bass , Lipid Metabolism , Methylhydrazines/adverse effects , Animals , Bass/growth & development , Bass/metabolism , Diet/veterinary , Lipid Metabolism/drug effects , Lipids , Liver/drug effects , Liver/metabolism , Mitochondria/drug effects , Mitochondria/metabolism
2.
Toxicol Appl Pharmacol ; 398: 115031, 2020 07 01.
Article En | MEDLINE | ID: mdl-32389661

Mildronate is a cardiac and neuroprotective drug that is widely used in some countries. By inhibiting carnitine biosynthesis, mildronate impairs the fatty acids transport into mitochondria, thereby decreasing the ß-oxidation intensity. Since 2016, it has been prohibited by the World Anti-Doping Agency (WADA). However, the information on its safety and its influence on the athletes' health is scarce. There are no published studies on whether mildronate-induced long-term metabolism "rearrangement" may cause negative effects on high-metabolic-rate organs and on the whole organism. Here, we demonstrate that long-term mildronate treatment of healthy mice induced global metabolism change at the transcriptome level in liver, heart, and brain. Mildronate treatment also induced some behavioral changes such as anxiety-related behavior and diminished explorative behavior. We also found that mildronate induced a dysbiosis, as manifested by an increase in Proteobacteria level in gut microbiome. At the same time, the absence of a statistically significant increase in mouse strength and endurance procedures suggests that mildronate effect on productivity is negligible. The sum of our data suggests that long-term treatment of healthy mice with mildronate induces dysbiosis and behavioral deviations despite the effectiveness of mildronate for cardiac and neurological diseases. Thus, we suggest that long-term mildronate treatment is undesirable or at the very least should be accompanied by prebiotics treatments, but this issue should be studied further.


Behavior, Animal/drug effects , Brain/drug effects , Gastrointestinal Microbiome/drug effects , Heart/drug effects , Liver/drug effects , Methylhydrazines/adverse effects , Proteobacteria/drug effects , Transcriptome/drug effects , Animals , Brain/metabolism , Carnitine/metabolism , Methylhydrazines/administration & dosage , Mice
5.
Drug Res (Stuttg) ; 66(5): 251-6, 2016 May.
Article En | MEDLINE | ID: mdl-26697890

Mildronate is an agent for cardioprotection and neuroprotection. This study aimed to evaluate the pharmacokinetic (PK) profiles, safety and tolerability of mildronate injection after single escalating doses and multiple doses in healthy Chinese subjects. We performed a randomized, open-label, single- and multiple-dose phase I trial including 3 doses of mildronate: 250, 500 and 750 mg. Plasma and urine samples were collected and concentrations of mildronate were analyzed by liquid chromatography-mass spectrometry (LC-MS/MS). PK parameters were calculated using noncompartmental analysis. Safety and tolerability was assessed throughout noting subjects' vital signs and monitoring adverse events (AEs) and conduct a comprehensive physical examination and laboratory analyses before and after the study. There was no significant difference in C 0, AUC0-t, AUC0-∞ among 3 single-dose groups, whereas T 1/2 had significant statistical difference which may be caused by the inhibition of metabolic enzymes. Single- and multiple-dose intravenous injection of mildronate exhibited linear PK profiles in the range of 250-750 mg. An unconspicuous accumulation phenomenon was found after multiple-dose mildronate administration. No significant gender difference was found and mildronate is primarily excreted by the kidney. No serious AEs were observed. The formulation was safe and well tolerated from 250 to 750 mg.


Cardiovascular Agents/pharmacokinetics , Methylhydrazines/pharmacokinetics , Adult , Asian People , Cardiovascular Agents/administration & dosage , Cardiovascular Agents/adverse effects , China , Chromatography, Liquid , Female , Healthy Volunteers , Humans , Injections , Male , Methylhydrazines/administration & dosage , Methylhydrazines/adverse effects , Tandem Mass Spectrometry , Young Adult
6.
Kardiologiia ; 54(4): 46-50, 2014.
Article Ru | MEDLINE | ID: mdl-25177785

In order to evaluate the effectiveness mildronate in rehabilitative treatment in connective tissue dysplasia examined 240 patients (24,41 ± 7,62 years, 130 men). All patients were treated with 5 ml of mildronate 10% intravenously for 10 days, then 1 capsule (250 mg), 2 times per day for 4 months. The therapy showed a significant decrease in asthenic complaints, reducing the incidence of violations repolarization I (p<0.05) and II infarction (p<0.05), a significant increase in end-diastolic volume (p<0.05), stroke volume (p<0.05), left ventricular ejection fraction (p<0.05) by echocardiography, increased exercise tolerance with the normalization of reaction to physical stress on a dystonic normotonichesky, improved quality of life. During the treatment was not recorded adverse events in patients receiving the drug. Portability mildronate majority of patients described as good to very good (average 8.67 points).


Connective Tissue Diseases/complications , Heart Diseases , Methylhydrazines , Adult , Asthenia/drug therapy , Asthenia/etiology , Cardiovascular Agents/administration & dosage , Cardiovascular Agents/adverse effects , Drug Administration Routes , Drug Monitoring , Exercise Tolerance/drug effects , Female , Heart Diseases/diagnosis , Heart Diseases/drug therapy , Heart Diseases/etiology , Heart Diseases/physiopathology , Heart Function Tests/drug effects , Heart Function Tests/methods , Humans , Male , Methylhydrazines/administration & dosage , Methylhydrazines/adverse effects , Myocardial Contraction/drug effects , Treatment Outcome
7.
J Biol Regul Homeost Agents ; 28(2): 263-70, 2014.
Article En | MEDLINE | ID: mdl-25001658

Biochemical and pharmacological evidence supports the hypothesis that the mechanism of action of mildronate [3-(2,2,2-trimethylhydrazinium)propionate dihydrate] is based on its regulatory effect on carnitine concentration. The present study demonstrates that carnitine acts as a neuroprotective agent both in optic nerve head and in retinal ganglion cell (RGC) by means of antioxidant and antiradical activities. In fact, carnitine normalized the increase in caspase-3, cellular apoptosis susceptibility protein (CAS) and inducible nitric oxide synthase (iNOS) expression by stabilizing mitochondrial membranes, as assessed by quantitative and qualitative analysis. This research shows that the neuroprotective effects of carnitine result, at least partially, from anti-neurodegenerative (anti-apoptotic) and anti-inflammatory mechanisms. It is suggested that the molecular conformation of carnitine can facilitate its easy binding to mitochondria, and regulate the expression of different signal molecules, hence maintaining normal cellular signaling and survival by modulating caspase-3 activity.


Cardiovascular Agents/adverse effects , Carnitine/metabolism , Methylhydrazines/adverse effects , Optic Nerve Diseases , Retinal Degeneration , Animals , Apoptosis/drug effects , Biological Transport, Active/drug effects , Cardiovascular Agents/pharmacology , Caspase 3/metabolism , Cell Survival/drug effects , Male , Methylhydrazines/pharmacology , Optic Nerve Diseases/chemically induced , Optic Nerve Diseases/metabolism , Optic Nerve Diseases/pathology , Optic Nerve Diseases/physiopathology , Rats , Rats, Wistar , Retinal Degeneration/chemically induced , Retinal Degeneration/metabolism , Retinal Degeneration/pathology , Retinal Degeneration/physiopathology , Retinal Ganglion Cells/metabolism , Retinal Ganglion Cells/pathology , Signal Transduction/drug effects
8.
Lik Sprava ; (1-2): 27-35, 2014.
Article Ru | MEDLINE | ID: mdl-24908956

Was examined 92 patients with congestive heart failure III-IV FC with fraction of emission left ventricle < 45% against coronary artery disease. Patients of control group received basic therapy (according to recommendations of the Ukrainian society of cardiology), the 1 group--in addition received a preparation of Vazonat within 15 days intravenously in a dose of 1000 mg a day further are out-patient within 1 month on 250 mg 3 times per os; the 2 group--under the same scheme a preparation of Vazonat and a day tranquilizer of Adapto in a dose of 500 mg twice a day throughout all term of supervision. It is established that addition of Vazonat to basic treatment leads to additional effect concerning improvement of indicators cardio-hemodynamic, to improvement congestive functions. Joint appointment of preparations of Vazonat and Adaptol against basic treatment leads to more expressed improvement congestive functions, to progressive reduction of degree of trouble, depression.


Anti-Anxiety Agents/therapeutic use , Biureas/therapeutic use , Cardiovascular Agents/therapeutic use , Heart Failure/drug therapy , Methylhydrazines/therapeutic use , Psychophysiologic Disorders/drug therapy , Aged , Anti-Anxiety Agents/administration & dosage , Anti-Anxiety Agents/adverse effects , Biureas/administration & dosage , Biureas/adverse effects , Cardiovascular Agents/administration & dosage , Cardiovascular Agents/adverse effects , Cognition/drug effects , Drug Therapy, Combination , Echocardiography , Exercise Test , Heart Failure/pathology , Heart Failure/physiopathology , Heart Failure/psychology , Hemodynamics/drug effects , Humans , Methylhydrazines/administration & dosage , Methylhydrazines/adverse effects , Middle Aged , Myocardial Contraction/drug effects , Myocardium/pathology , Neuropsychological Tests , Psychophysiologic Disorders/physiopathology , Psychophysiologic Disorders/psychology , Severity of Illness Index , Treatment Outcome
9.
Kardiologiia ; 54(11): 11-9, 2014.
Article Ru | MEDLINE | ID: mdl-25902653

We examined 140 patients (mean age 54.8±3.1 years) with ST elevation acute coronary syndrome resulting in Q-wave myocardial infarction of the left ventricle. From the first hours complex therapy of these patients comprised meldonium (1 g/day intravenously for 2 weeks then orally until 1.5 months). Therapy with meldonium accelerated restoration of left ventricular diastolic function what was in agreement with lowering of NT-proBNT concentration in blood. It was established that administration of meldonium led to reduction of number of high grade ventricular extrasystoles during first 6 hours after thrombolysis, to lowering of blood concentration of lipoperoxide degradation products. Early use of meldonium decreases probability of emergence of fatal arrhythmias and improves prognosis of hospital stage of rehabilitation of patients with acute coronary syndrome resulting in Q-wave myocardial infarction.


Acute Coronary Syndrome , Diastole/drug effects , Methylhydrazines , Natriuretic Peptide, Brain/blood , Peptide Fragments/blood , Ventricular Function, Left/drug effects , Acute Coronary Syndrome/blood , Acute Coronary Syndrome/diagnosis , Acute Coronary Syndrome/drug therapy , Acute Coronary Syndrome/physiopathology , Cardiovascular Agents/administration & dosage , Cardiovascular Agents/adverse effects , Coronary Angiography/methods , Drug Administration Routes , Drug Monitoring , Electrocardiography , Female , Humans , Male , Methylhydrazines/administration & dosage , Methylhydrazines/adverse effects , Middle Aged , Prognosis , Treatment Outcome
10.
Zh Nevrol Psikhiatr Im S S Korsakova ; 113(9 Pt 2): 33-42, 2013.
Article Ru | MEDLINE | ID: mdl-24107893

Detailed clinical data about patients who used emergency services during 2011 are presented. The main attention is focused on the state of patients with acute and chronic brain ischemia before and after treatment with mildronate. Mean age of patients with ischemic stroke and chronic brain ischemia was 63.4 and 57.7 years, respectively. Mildronate was injected slowly intravenously in one dose 1000 mg (10 ml of 10% solution). The results obtained in the study allow to recommend mildronate for such patients and provide the useful information to physicians and medical attendants about current methods of diagnosis and treatment of patients with acute and chronic brain ischemia in out- and inpatient health services.


Brain Ischemia/drug therapy , Emergency Treatment , Methylhydrazines/therapeutic use , Stroke/drug therapy , Adult , Aged , Aged, 80 and over , Female , Humans , Injections, Intravenous , Male , Methylhydrazines/administration & dosage , Methylhydrazines/adverse effects , Middle Aged , Treatment Outcome
11.
Clin Drug Investig ; 33(10): 755-60, 2013 Oct.
Article En | MEDLINE | ID: mdl-23949899

BACKGROUND AND OBJECTIVE: Mildronate, an inhibitor of carnitine-dependent metabolism, is considered to be an anti-ischemic drug. This study is designed to evaluate the efficacy and safety of mildronate injection in treating acute ischemic stroke. METHODS: We performed a randomized, double-blind, multicenter clinical study of mildronate injection for treating acute cerebral infarction. 113 patients in the experimental group received mildronate injection, and 114 patients in the active-control group received cinepazide injection. In addition, both groups were given aspirin as a basic treatment. Modified Rankin Scale (mRS) score was performed at 2 weeks and 3 months after treatment. National Institutes of Health Stroke Scale (NIHSS) score and Barthel Index (BI) score were performed at 2 weeks after treatment, and then vital signs and adverse events were evaluated. RESULTS: A total of 227 patients were randomized to treatment (n = 113, mildronate; n = 114, active-control). After 3 months, there was no significant difference for the primary endpoint between groups categorized in terms of mRS scores of 0-1 and 0-2 (p = 0.52 and p = 0.07, respectively). There were also no significant differences for the secondary endpoint between groups categorized in terms of NIHSS scores of >5 and >8 (p = 0.98 and p = 0.97, respectively) or BI scores of >75 and >95 (p = 0.49 and p = 0.47, respectively) at 15 days. The incidence of serious adverse events was similar between the two groups. CONCLUSION: Mildronate injection is as effective and safe as cinepazide injection in treating acute cerebral infarction.


Brain Ischemia/drug therapy , Cardiovascular Agents/therapeutic use , Methylhydrazines/therapeutic use , Stroke/drug therapy , Aged , Brain Ischemia/diagnosis , Brain Ischemia/physiopathology , Cardiovascular Agents/adverse effects , Double-Blind Method , Female , Humans , Male , Methylhydrazines/adverse effects , Middle Aged , Stroke/diagnosis , Stroke/physiopathology , Treatment Outcome
12.
Fundam Clin Pharmacol ; 27(1): 120-8, 2013 Feb.
Article En | MEDLINE | ID: mdl-21679246

Mildronate has been used as antianginal drug in parts of Europe for many years, but its pharmacokinetic (PK) properties in humans remain unclear. This study was designed to assess and compare the PK properties of mildronate capsules after single escalating oral dose and multiple doses in healthy Chinese volunteers. Volunteers were randomly assigned to receive a single dose of 250, 500, 1000, 1250 or 1500 mg of mildronate capsules. Those who received the 500-mg dose continued on the multiple-dose phase and received 500 mg three times a day for 13 days. Plasma drug concentrations were analysed by ultraperformance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS). Tolerability was assessed throughout the study. A total of 40 Chinese volunteers were enrolled in the study. No period or sequence effect was observed. Area under the concentration and C(max) were increased proportionally with the dose levels, whereas t(1/2) and V(d)/f were dependent on the dose. Nonlinear PK properties were found at doses of 250-1500 mg. There was an accumulation after multiple-dose administration. No serious adverse events (AEs) were reported in the PK study. The formulation was well tolerated.


Cardiotonic Agents/pharmacokinetics , Enzyme Inhibitors/pharmacokinetics , Methylhydrazines/pharmacokinetics , gamma-Butyrobetaine Dioxygenase/antagonists & inhibitors , Adult , Calibration , Capsules , Cardiotonic Agents/administration & dosage , Cardiotonic Agents/adverse effects , Cardiotonic Agents/blood , China , Dose-Response Relationship, Drug , Enzyme Inhibitors/administration & dosage , Enzyme Inhibitors/adverse effects , Enzyme Inhibitors/blood , Female , Half-Life , Humans , Limit of Detection , Male , Metabolic Clearance Rate , Methylhydrazines/administration & dosage , Methylhydrazines/adverse effects , Methylhydrazines/blood , Reproducibility of Results , Young Adult
13.
Lik Sprava ; (7): 68-74, 2012.
Article Ru | MEDLINE | ID: mdl-23350117

Cerebrovascular pathology has long moved from the category of a single medical problem in the social problem. Progression of vascular lesions of the brain results in significant disability, and in the later stages interfere with the ability to self-service and significantly reduces the quality of life. The key link is ischemic brain damage, or glutamate cascade, which many researchers believe trigger excitotoxic damage and a major cause of neuronal death. One important component of effective control of the effects of ischemic disorders is complex neuro-cytoprotective therapy. To correct for the effects of both acute and chronic ischemia of the brain need to effectively act in several directions simultaneously, normalizing metabolic changes, eliminating the cytokine imbalance transcription violations, reducing the severity of oxidative stress and excitotoxicity.


Cardiovascular Agents/therapeutic use , Cardiovascular Diseases/drug therapy , Cerebrovascular Disorders/drug therapy , Hypoxia/drug therapy , Ischemia/drug therapy , Methylhydrazines/therapeutic use , Cardiovascular Agents/administration & dosage , Cardiovascular Agents/adverse effects , Cardiovascular Diseases/etiology , Cardiovascular Diseases/pathology , Cerebrovascular Circulation/drug effects , Cerebrovascular Disorders/etiology , Cerebrovascular Disorders/pathology , Energy Metabolism/drug effects , Humans , Hypoxia/complications , Hypoxia/pathology , Ischemia/complications , Ischemia/pathology , Methylhydrazines/administration & dosage , Methylhydrazines/adverse effects , Randomized Controlled Trials as Topic
14.
Medicina (Kaunas) ; 47(10): 544-51, 2011.
Article En | MEDLINE | ID: mdl-22186118

OBJECTIVE: To assess the efficacy of various doses of Mildronate in combination with standard therapy for the exercise tolerance of patients with stable angina pectoris. The primary efficacy variable was the change in exercise time in bicycle ergometry from the baseline to 12 weeks of treatment. The secondary endpoints were the changes in maximum achieved load and time to the onset of angina from the baseline to week 12. MATERIAL AND METHODS: A total of 512 patients with chronic coronary heart disease who had ischemia as the limiting factor in the exercise test from 72 study centers in 4 countries were enrolled in this prospective, randomized, double-blind, placebo controlled phase 2 study. The patients were assigned to either 4 groups receiving standard therapy plus Mildronate at different daily doses or 1 group receiving standard therapy plus placebo. RESULTS: The mean change in the total exercise time in the mildronate 100 mg and mildronate 300 mg groups was -2.12±108.45 and 11.48±62.03 seconds, respectively. The mean change for the placebo group was -7.10±81.78 seconds. The difference between Mildronate 100 mg and 300 mg and placebo groups was not significant. Patients in the Mildronate 1000 mg group showed a remarkable increase in the mean change in the total exercise time (35.18±53.29 seconds, P=0.002). Mildronate at a dose of 3000 mg caused a smaller increase as compared with a dose of 1000 mg. Similar changes in the secondary end parameters were observed. CONCLUSION: The most effective dose of Mildronate in combination with standard therapy was found to be 500 mg twice a day.


Angina, Stable/drug therapy , Angina, Stable/physiopathology , Cardiovascular Agents/administration & dosage , Exercise Tolerance , Methylhydrazines/administration & dosage , Adult , Aged , Aged, 80 and over , Cardiovascular Agents/adverse effects , Dose-Response Relationship, Drug , Female , Humans , Male , Methylhydrazines/adverse effects , Middle Aged , Treatment Outcome
15.
Lik Sprava ; (5-6): 109-16, 2010.
Article Ru | MEDLINE | ID: mdl-21488376

In the course of observation over 40 patients after an old myocarditis against general systemic diseases of connective tissue who had been given a pharmacotherapy regarding main disease and a chronic heart failure, additionally Vazonat (campaign of "Olajnfarm", Latvia), preparation of the myocardial cytoprotection was prescribed in a therapeutic dose of 500 mg per day. Vazonat inclusion in basic therapy during 1 month was accompanied by improvement of a clinical condition of the patients, reduction of heart failure signs, and improvement of life quality.


Cardiotonic Agents/therapeutic use , Connective Tissue Diseases/complications , Heart Failure/drug therapy , Methylhydrazines/therapeutic use , Myocarditis/complications , Myocardium/metabolism , Adult , Cardiotonic Agents/administration & dosage , Cardiotonic Agents/adverse effects , Connective Tissue Diseases/metabolism , Echocardiography , Electrocardiography , Exercise Test , Female , Heart Failure/diagnostic imaging , Heart Failure/etiology , Heart Failure/metabolism , Humans , Male , Methylhydrazines/administration & dosage , Methylhydrazines/adverse effects , Middle Aged , Myocarditis/metabolism , Quality of Life , Severity of Illness Index , Treatment Outcome , Young Adult
16.
Georgian Med News ; (122): 25-9, 2005 May.
Article Ru | MEDLINE | ID: mdl-15988077

In developed countries chronic heart failure (CHF) is one of the main reasons of death and physical disability. CHF affects approximately 1-2% of the population and its prevalence is still increasing. Today ACE inhibitors, beta-blockers, diuretics are the first line drugs in treatment of CHF. Mildronate is a new drug optimizing cardiac energy metabolism and could be an effective approach in CHF patients' management. The aim of the study was to investigate the efficacy and safety of mildronate in treatment of CHF (NYHA III-IV funct. class) patients. 110 patients with CHF, stable on conventional treatment (diuretics, ACE inhibitors, beta-blokers, digoxin), were treated additionally with mildronate. Assessment was performed with clinical data, FC change, ECO-cardiography, 6-minute walk test. Mildronate showed to be an effective drug in complex treatment of chronic heart failure.


Cardiac Output, Low/drug therapy , Methylhydrazines/therapeutic use , Chronic Disease , Drug Therapy, Combination , Female , Humans , Male , Methylhydrazines/adverse effects , Treatment Outcome
17.
Vopr Onkol ; 45(3): 279-82, 1999.
Article Ru | MEDLINE | ID: mdl-10443231

Mutagenic and carcinogenic properties of mildronate (3-[2.2.2.-trimethyl hydrazonium]-propionate) have been studied for its marked immuno-stimulating and anti-ischemic action. When dosage up to 1,000 mg/dish was used no reversal of base-pair substitution or frame shift in S.typhimurium was observed. In drosophila females treated with mildronate, mosaic patches were, on the average, as frequent as in control. Although chronic treatment of female mice B6D2F1, C3H and SHR with mildronate was not followed by any change in tumor incidence, mammary gland adenocarcinoma development was slightly inhibited in mice C3H and SHR. The latter effect was in correlation with the antigonadotropic one of the drug and was not determined by its estrogenous properties. This pointed to the absence of mutagenic and carcinogenic properties which was confirmed in two short-term and one chronic experiments on mice of the three lines.


Adjuvants, Immunologic/adverse effects , Carcinogens , Methylhydrazines/adverse effects , Mutagens , Adenocarcinoma/prevention & control , Animals , Drosophila melanogaster , Female , Mammary Neoplasms, Experimental/prevention & control , Mice , Mice, Inbred Strains
18.
Gastroenterology ; 98(6): 1532-7, 1990 Jun.
Article En | MEDLINE | ID: mdl-2338191

Photodynamic therapy is a relatively new method for the local destruction of tumors based on the administration of a photosensitizing agent that is retained in tumors and then activated to produce cytotoxic agents following irradiation with light. The selective retention of photosensitizers by dimethylhydrazine-induced colonic tumors over adjacent normal tissue is small (2:1, tumor to normal), making the possibility of producing selective tumor necrosis with total sparing of normal tissue difficult. Colonic cancers and adjacent normal colon were treated with the same light doses from an argon-pumped dye laser 48 h after intravenous injection of 0.5 or 5 mg/kg of the photosensitizer, aluminum-sulfonated phthalocyanine. There was little difference between the amount of necrosis in the tumor and the adjacent normal colon if the injected dose of photosensitizer was 5 mg/kg. However, at the lower dose of 0.5 mg/g, up to 2 mm of necrosis could be produced in the tumor without damaging the normal colon. In vivo fluorescence measurements showed that the photosensitizer was photodegraded during irradiation. This was confirmed by in vitro fluorescence scans of the normal colon after irradiation; the fluorescence from the photosensitizer was lowest at the point of irradiation. It is postulated that at low dosage, selective necrosis can occur because the photosensitizer is photodegraded in the normal colon before a threshold photodynamic dose is reached, whereas in tumor containing twice as much photosensitizer, a photodynamic threshold dose can be achieved and necrosis produced.


Carcinogens , Colonic Neoplasms/drug therapy , Dimethylhydrazines/adverse effects , Indoles/therapeutic use , Methylhydrazines/adverse effects , Photochemotherapy , 1,2-Dimethylhydrazine , Animals , Colon/metabolism , Colonic Neoplasms/chemically induced , Colonic Neoplasms/pathology , Fluorescence , Indoles/administration & dosage , Indoles/metabolism , Injections, Intravenous , Isoindoles , Laser Therapy , Male , Necrosis , Photochemistry , Photochemotherapy/methods , Pigments, Biological/administration & dosage , Pigments, Biological/therapeutic use , Rats , Rats, Inbred Strains
19.
Cancer ; 65(8): 1748-52, 1990 Apr 15.
Article En | MEDLINE | ID: mdl-1969325

The effect of endotoxin on colon tumors was studied in male Sprague-Dawley rats. Colon tumors were induced in weanling rats by the administration of 20 weekly subcutaneous injections of 1,2-dimethylhydrazine (DMH). When colon tumors were detected by colonoscopy in 80% of the rats around week 24 after DMH injection, the animals were divided randomly into two groups. One group served as the control. The other group received six endotoxin (Escherichia coli) treatments every fifth day. The first dose was 50 micrograms/100 g (intraperitoneally); the remaining doses were 100 micrograms/100 g (subcutaneously). Rats were killed 2 weeks after the last endotoxin injection. Endotoxin treatments resulted in larger colon tumors. The median tumor size was 71 mm2 for endotoxin-treated and 31 mm2 for untreated rats (P less than 0.02). Endotoxin treatments also resulted in a significantly higher incidence (P less than 0.05) of ulcer development in the small intestine, that is 47% in the endotoxin-treated versus 23% in the untreated rats. After a single subcutaneous injection of endotoxin (100 micrograms/100 g), the colon mucosal reduced glutathione (GSH) level was raised by 21% at 16 hours, reached a peak on day 2, then decreased to baseline by day 4. The increased GSH level in the colon mucosa was maintained up to the third endotoxin injection. By the fifth injection, no increase in the GSH level was observed. These results suggest that the growth of colon tumors in rats induced by DMH could be enhanced by endotoxin treatments. The enhanced tumor growth may be due to an increase in the colon GSH level and/or other mediators released by macrophages as a result of endotoxin treatments.


Carcinogens , Colonic Neoplasms/chemically induced , Dimethylhydrazines/adverse effects , Endotoxins/pharmacology , Escherichia coli , Methylhydrazines/adverse effects , 1,2-Dimethylhydrazine , Animals , Cocarcinogenesis , Colon/analysis , Colon/enzymology , Colonic Neoplasms/enzymology , Colonic Neoplasms/pathology , Endotoxins/administration & dosage , Glutathione/analysis , Injections, Intraperitoneal , Injections, Subcutaneous , Intestinal Mucosa/analysis , Intestinal Mucosa/enzymology , Male , Random Allocation , Rats , Rats, Inbred Strains , gamma-Glutamyltransferase/analysis
20.
Gastroenterology ; 81(3): 475-80, 1981 Sep.
Article En | MEDLINE | ID: mdl-6166510

The influence of adaptive cell proliferation on colonic carcinogenesis was studied in male Fischer rats with a defunctioning transverse colostomy that was closed 4 wk later. Control observations were made in other rats after colonic transection, repeated at 4 wk, after laparotomy alone, or after permanent colostomy. Tumors were induced by 1,2-dimethylhydrazine (total dose, 300 mg/kg) over 11 wk, starting 2 days after the second operation. After creation of the colostomy, amounts of protein, RNA, and DNA in the distal colon halved in 4 wk (p less than 0.001), but returned to normal 7 days after restoration of colonic continuity. This reactive hyperplasia promoted the development of distal colonic carcinomas, as compared with rats having repeated transection of the bowel (incidence 32% vs. 6%; p less than 0.03). Although the amounts of protein and nucleic acid in the proximal colon were unchanged by transverse colostomy, values increased by 18%-59% 4 wk after colostomy closure (p = 0.05-0.002); nonetheless, the yield of tumors in this segment was unaltered. Suture-line cancers were commoner after repeat transection than after colostomy closure (76% vs. 39%; p less than 0.01). These data confirm the promotional effect of increased cell proliferation on intestinal carcinogenesis.


Colonic Neoplasms/chemically induced , Colostomy , Dimethylhydrazines/adverse effects , Methylhydrazines/adverse effects , Animals , Cell Division/drug effects , Colon/cytology , Colon/metabolism , DNA/metabolism , Male , Proteins/metabolism , RNA/metabolism , Rats
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