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1.
Life Sci ; 293: 120333, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35051422

RESUMO

Ageing is the most significant risk factor for cardiovascular diseases. l-Carnitine has a potent cardioprotective effect and its synthesis decreases during ageing. At the same time, there are pharmaceuticals, such as mildronate which, on the contrary, are aimed at reducing the concentration of l-carnitine in the heart and lead to slows down the oxidation of fatty acids in mitochondria. Despite this, both l-carnitine and mildronate are positioned as cardio protectors. We showed that l-carnitine supplementation to the diet of 15-month-old mice increased expression of the PGC-1α gene, which is responsible for the regulation of fatty acid oxidation, and the Nrf2 gene, which is responsible for protecting mitochondria by regulating the expression of antioxidants and mitophagy, in the heart. Mildronate activated the expression of genes that regulate glucose metabolism. Probably, this metabolic shift may protect the mitochondria of the heart from the accumulation of acyl-carnitine, which occurs during the oxidation of fatty acids under oxygen deficiency. Both pharmaceuticals impacted the gut microbiome bacterial composition. l-Carnitine increased the level of Lachnoanaerobaculum and [Eubacterium] hallii group, mildronate increased the level of Bifidobacterium, Rikinella, Christensenellaceae. Considered, that these bacteria for protection the organism from various pathogens and chronic inflammation. Thus, we suggested that the positive effects of both drugs on the mitochondria metabolism and gut microbiome bacterial composition may contribute to the protection of the heart during ageing.


Assuntos
Envelhecimento/metabolismo , Fármacos Cardiovasculares/farmacologia , Carnitina/farmacologia , Microbioma Gastrointestinal/fisiologia , Metilidrazinas/farmacologia , Mitocôndrias Cardíacas/metabolismo , Envelhecimento/efeitos dos fármacos , Animais , Bifidobacterium/metabolismo , DNA Mitocondrial/metabolismo , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias Cardíacas/efeitos dos fármacos
2.
Int J Mol Sci ; 21(19)2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33050117

RESUMO

A mismatch between ß-oxidation and the tricarboxylic acid cycle (TCA) cycle flux in mitochondria produces an accumulation of lipid metabolic intermediates, resulting in both blunted metabolic flexibility and decreased glucose utilization in the affected cells. The ability of the cell to switch to glucose as an energy substrate can be restored by reducing the reliance of the cell on fatty acid oxidation. The inhibition of the carnitine system, limiting the carnitine shuttle to the oxidation of lipids in the mitochondria, allows cells to develop a high plasticity to metabolic rewiring with a decrease in fatty acid oxidation and a parallel increase in glucose oxidation. We found that 3-(2,2,2-trimethylhydrazine)propionate (THP), which is able to reduce cellular carnitine levels by blocking both carnitine biosynthesis and the cell membrane carnitine/organic cation transporter (OCTN2), was reported to improve mitochondrial dysfunction in several diseases, such as Huntington's disease (HD). Here, new THP-derived carnitine-lowering agents (TCL), characterized by a high affinity for the OCTN2 with a minimal effect on carnitine synthesis, were developed, and their biological activities were evaluated in both in vitro and in vivo HD models. Certain compounds showed promising biological activities: reducing protein aggregates in HD cells, ameliorating motility defects, and increasing the lifespan of HD Drosophila melanogaster.


Assuntos
Drosophila melanogaster/efeitos dos fármacos , Doença de Huntington/tratamento farmacológico , Doença de Huntington/metabolismo , Longevidade/efeitos dos fármacos , Metilidrazinas/farmacologia , Membro 5 da Família 22 de Carreadores de Soluto/antagonistas & inibidores , Membro 5 da Família 22 de Carreadores de Soluto/metabolismo , Animais , Carnitina/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Drosophila melanogaster/genética , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Camundongos , Simulação de Acoplamento Molecular , Agregação Patológica de Proteínas/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Membro 5 da Família 22 de Carreadores de Soluto/genética , Transfecção , Resultado do Tratamento
3.
J Nutr ; 150(9): 2322-2335, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32720689

RESUMO

BACKGROUND: Fish cannot use carbohydrate efficiently and instead utilize protein for energy supply, thus limiting dietary protein storage. Protein deposition is dependent on protein turnover balance, which correlates tightly with cellular energy homeostasis. Mitochondrial fatty acid ß-oxidation (FAO) plays a crucial role in energy metabolism. However, the effect of remodeled energy homeostasis caused by inhibited mitochondrial FAO on protein deposition in fish has not been intensively studied. OBJECTIVES: This study aimed to identify the regulatory role of mitochondrial FAO in energy homeostasis maintenance and protein deposition by studying lipid, glucose, and protein metabolism in fish. METHODS: Carnitine-depleted male Nile tilapia (initial weight: 4.29 ± 0.12 g; 3 mo old) were established by feeding them with mildronate diets (1000 mg/kg/d) for 6 wk. Zebrafish deficient in the carnitine palmitoyltransferase 1b gene (cpt1b) were produced by using CRISPR/Cas9 gene-editing technology, and their males (154 ± 3.52 mg; 3 mo old) were used for experiments. Normal Nile tilapia and wildtype zebrafish were used as controls. We assessed nutrient metabolism and energy homeostasis-related biochemical and molecular parameters, and performed 14C-labeled nutrient tracking and transcriptomic analyses. RESULTS: The mitochondrial FAO decreased by 33.1-88.9% (liver) and 55.6-68.8% (muscle) in carnitine-depleted Nile tilapia and cpt1b-deficient zebrafish compared with their controls (P < 0.05). Notably, glucose oxidation and muscle protein deposition increased by 20.5-24.4% and 6.40-8.54%, respectively, in the 2 fish models compared with their corresponding controls (P < 0.05). Accordingly, the adenosine 5'-monophosphate-activated protein kinase/protein kinase B-mechanistic target of rapamycin (AMPK/AKT-mTOR) signaling was significantly activated in the 2 fish models with inhibited mitochondrial FAO (P < 0.05). CONCLUSIONS: These data show that inhibited mitochondrial FAO in fish induces energy homeostasis remodeling and enhances glucose utilization and protein deposition. Therefore, fish with inhibited mitochondrial FAO could have high potential to utilize carbohydrate. Our results demonstrate a potentially new approach for increasing protein deposition through energy homeostasis regulation in cultured animals.


Assuntos
Ácidos Graxos/metabolismo , Glucose/metabolismo , Metilidrazinas/farmacologia , Mitocôndrias/metabolismo , Proteínas/metabolismo , Adjuvantes Imunológicos/farmacologia , Animais , Carnitina O-Palmitoiltransferase/genética , Carnitina O-Palmitoiltransferase/metabolismo , Células Cultivadas , Ciclídeos , Citocromos b/genética , Citocromos b/metabolismo , DNA , Metabolismo Energético , Hepatócitos/efeitos dos fármacos , Hepatócitos/fisiologia , Homeostase , Insulina , Masculino , Mutação , Oxirredução , Peixe-Zebra
4.
Fish Shellfish Immunol ; 68: 500-508, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28774846

RESUMO

Energy metabolism plays important roles in stress resistance and immunity in mammals, however, such functions have not been established in fish. In the present study, Nile tilapia (Oreochromis niloticus) was fed with mildronate, an inhibitor of mitochondrial fatty acid (FA) ß-oxidation, for six weeks subsequently challenged with Aeromonas hydrophila and ammonia nitrogen exposure. Mildronate treatment reduced significantly l-carnitine concentration and mitochondrial FA ß-oxidation efficiency, while it increased lipid accumulation in liver. The fish with inhibited hepatic FA catabolism had lower survival rate when exposed to Aeromonas hydrophila and ammonia nitrogen. Moreover, fish fed mildronate supplemented diet had lower immune enzymes activities and anti-inflammatory cytokine genes expressions, but had higher pro-inflammatory cytokine genes expressions. However, the oxidative stress-related biochemical indexes were not significantly affected by mildronate treatment. Taken together, inhibited mitochondrial FA ß-oxidation impaired stress resistance ability in Nile tilapia mainly through inhibiting immune functions and triggering inflammation. This is the first study showing the regulatory effects of lipid catabolism on stress resistance and immune functions in fish.


Assuntos
Ciclídeos , Ácidos Graxos/metabolismo , Doenças dos Peixes/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Metilidrazinas/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Aeromonas hydrophila/fisiologia , Amônia/metabolismo , Ração Animal , Animais , Carnitina/metabolismo , Ciclídeos/metabolismo , Dieta , Suplementos Nutricionais , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/microbiologia , Mitocôndrias/efeitos dos fármacos , Nitrogênio/metabolismo , Oxirredução/efeitos dos fármacos , Distribuição Aleatória
5.
J Physiol ; 595(17): 5765-5780, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28605113

RESUMO

KEY POINTS: Meldonium inhibits endogenous carnitine synthesis and tissue uptake, and accelerates urinary carnitine excretion, although the impact of meldonium-mediated muscle carnitine depletion on whole-body fuel selection, and muscle fuel metabolism and its molecular regulation is under-investigated. Ten days of oral meldonium administration did not impact on food or fluid intake, physical activity levels or body weight gain in the rat, whereas it depleted muscle carnitine content (all moieties), increased whole-body carbohydrate oxidation and muscle and liver glycogen utilization, and reduced whole-body fat oxidation. Meldonium reduced carnitine transporter protein expression across muscles of different contractile and metabolic phenotypes. A TaqMan PCR low-density array card approach revealed the abundance of 189 mRNAs regulating fuel selection was altered in soleus muscle by meldonium, highlighting the modulation of discrete cellular functions and metabolic pathways. These novel findings strongly support the premise that muscle carnitine availability is a primary regulator of fuel selection in vivo. ABSTRACT: The body carnitine pool is primarily confined to skeletal muscle, where it regulates carbohydrate (CHO) and fat usage. Meldonium (3-(2,2,2-trimethylhydrazinium)-propionate) inhibits carnitine synthesis and tissue uptake, although the impact of carnitine depletion on whole-body fuel selection, muscle fuel metabolism and its molecular regulation is under-investigated. Male lean Zucker rats received water (control, n = 8) or meldonium-supplemented water (meldonium, n = 8) for 10 days [1.6 g kg-1 body mass (BM) day-1 days 1-2, 0.8 g kg-1  BM day-1 thereafter]. From days 7-10, animals were housed in indirect calorimetry chambers after which soleus muscle and liver were harvested. Food and fluid intake, weight gain and physical activity levels were similar between groups from days 7 to 10. Compared to control, meldonium depleted muscle total carnitine (P < 0.001) and all carnitine esters. Furthermore, whole-body fat oxidation was less (P < 0.001) and CHO oxidation was greater (P < 0.05) compared to the control, whereas soleus and liver glycogen contents were less (P < 0.01 and P < 0.01, respectively). In a second study, male Wistar rats received water (n = 8) or meldonium-supplemented water (n = 8) as above, and kidney, heart and extensor digitorum longus muscle (EDL) and soleus muscles were collected. Compared to control, meldonium depleted total carnitine content (all P < 0.001), reduced carnitine transporter protein and glycogen content, and increased pyruvate dehydrogenase kinase 4 mRNA abundance in the heart, EDL and soleus. In total, 189 mRNAs regulating fuel selection were differentially expressed in soleus in meldonium vs. control, and a number of cellular functions and pathways strongly associated with carnitine depletion were identified. Collectively, these data firmly support the premise that muscle carnitine availability is a primary regulator of fuel selection in vivo.


Assuntos
Carnitina/metabolismo , Metilidrazinas/farmacologia , Músculo Esquelético/efeitos dos fármacos , Animais , Metabolismo Energético/efeitos dos fármacos , Glicogênio/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Atividade Motora/efeitos dos fármacos , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , RNA Mensageiro/metabolismo , Ratos Wistar , Ratos Zucker , Membro 5 da Família 22 de Carreadores de Soluto/metabolismo
6.
Bull Exp Biol Med ; 160(1): 45-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26601841

RESUMO

For development of a pharmaceutical composition improving physical performance, effects of various drugs and their combinations on forced swimming test performance were studied on laboratory rats. Maximum increase in animal performance was produced by a 3-component composition asparcam+mildronate+metaprote in proportion of 5.0, 10.7, and 14.3 mg/kg, respectively. No changes in blood serum biochemistry and morphological composition of the peripheral blood were detected after single intragastric administration of the composition.


Assuntos
Antioxidantes/farmacologia , Ácido Aspártico/farmacologia , Benzimidazóis/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Metilidrazinas/farmacologia , Substâncias para Melhoria do Desempenho/farmacologia , Resistência Física/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , Antioxidantes/administração & dosagem , Ácido Aspártico/administração & dosagem , Desempenho Atlético , Benzimidazóis/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Combinação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Ecdisterona/administração & dosagem , Ecdisterona/farmacologia , Metabolismo Energético/efeitos dos fármacos , Metilidrazinas/administração & dosagem , Substâncias para Melhoria do Desempenho/administração & dosagem , Fenitoína/administração & dosagem , Fenitoína/farmacologia , Proteínas/metabolismo , Ratos , Natação , Suporte de Carga
7.
Life Sci ; 117(2): 84-92, 2014 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-25301199

RESUMO

AIMS: Trimethylamine-N-oxide (TMAO) is produced in host liver from trimethylamine (TMA). TMAO and TMA share common dietary quaternary amine precursors, carnitine and choline, which are metabolized by the intestinal microbiota. TMAO recently has been linked to the pathogenesis of atherosclerosis and severity of cardiovascular diseases. We examined the effects of anti-atherosclerotic compound meldonium, an aza-analogue of carnitine bioprecursor gamma-butyrobetaine (GBB), on the availability of TMA and TMAO. MAIN METHODS: Wistar rats received L-carnitine, GBB or choline alone or in combination with meldonium. Plasma, urine and rat small intestine perfusate samples were assayed for L-carnitine, GBB, choline and TMAO using UPLC-MS/MS. Meldonium effects on TMA production by intestinal bacteria from L-carnitine and choline were tested. KEY FINDINGS: Treatment with meldonium significantly decreased intestinal microbiota-dependent production of TMA/TMAO from L-carnitine, but not from choline. 24hours after the administration of meldonium, the urinary excretion of TMAO was 3.6 times lower in the combination group than in the L-carnitine-alone group. In addition, the administration of meldonium together with L-carnitine significantly increased GBB concentration in blood plasma and in isolated rat small intestine perfusate. Meldonium did not influence bacterial growth and bacterial uptake of L-carnitine, but TMA production by the intestinal microbiota bacteria K. pneumoniae was significantly decreased. SIGNIFICANCE: We have shown for the first time that TMA/TMAO production from quaternary amines could be decreased by targeting bacterial TMA-production. In addition, the production of pro-atherogenic TMAO can be suppressed by shifting the microbial degradation pattern of supplemental/dietary quaternary amines.


Assuntos
Vias Biossintéticas/efeitos dos fármacos , Carnitina/metabolismo , Trato Gastrointestinal/microbiologia , Metilaminas/metabolismo , Metilidrazinas/farmacologia , Microbiota/fisiologia , Animais , Betaína/administração & dosagem , Betaína/análogos & derivados , Betaína/sangue , Vias Biossintéticas/fisiologia , Isótopos de Carbono/metabolismo , Carnitina/administração & dosagem , Carnitina/sangue , Carnitina/urina , Colina/metabolismo , Cromatografia Líquida de Alta Pressão , Metilaminas/urina , Ratos , Ratos Wistar , Estatísticas não Paramétricas , Espectrometria de Massas em Tandem
8.
J Neurosci Res ; 92(3): 338-46, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24273007

RESUMO

Mildronate, a carnitine congener drug, previously has been shown to provide neuroprotection in an azidothymidine-induced mouse model of neurotoxicity and in a Parkinson's disease rat model. The aim of this study was to investigate the effects of mildronate treatment on cognition and pathology in Alzheimer's disease (AD) model mice (APP(SweDI)). Mildronate was administered i.p. daily at 50 or 100 mg/kg for 28 days. At the end of treatment, the animals were behaviorally and cognitively tested, and brains were assessed for AD-related pathology, inflammation, synaptic markers, and acetylcholinesterase (AChE). The data show that mildronate treatment significantly improved animal performance in water maze and social recognition tests, lowered amyloid-ß deposition in the hippocampus, increased expression of the microglia marker Iba-1, and decreased AChE staining, although it did not alter expression of proteins involved in synaptic plasticity (GAP-43, synaptophysin, and GAD67). Taken together, these findings indicate mildronate's ability to improve cognition and reduce amyloid-ß pathology in a mouse model of AD and its possible therapeutic utility as a disease-modifying drug in AD patients.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Transtornos Cognitivos/tratamento farmacológico , Metilidrazinas/uso terapêutico , Acetilcolinesterase/metabolismo , Adjuvantes Imunológicos/farmacologia , Doença de Alzheimer/complicações , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Análise de Variância , Animais , Transtornos Cognitivos/etiologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Comportamento Exploratório/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Glutamato Descarboxilase/metabolismo , Humanos , Locomoção/efeitos dos fármacos , Locomoção/genética , Metilidrazinas/farmacologia , Camundongos , Camundongos Transgênicos , Comportamento Social
9.
Bone ; 53(1): 277-83, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23207800

RESUMO

The effects of BPs on bone formation during mechanical loading are still unknown. In this study, we evaluated the effect of minodronate on the cortical bone response to mechanical loading applied using a 4-point bending device. We used six-month old female Wistar rats and randomized into five groups (N=10/group): Vehicle administration (VEH), low dose minodronate administration (MIN-L, 0.01 mg/kg BW), middle dose minodronate administration (MIN-M, 0.1mg/kg BW), high-dose minodronate administration (MIN-H 1mg/kg BW), and very high-dose minodronate administration (MIN-VH, 10mg/kg BW). Minodronate or vehicle was administered orally using the feeding needle at a dosage 3 times/week for 3 weeks. Loads on the right tibia at 38 N for 36 cycles at 2 Hz were applied in vivo by 4-point bending on the same day for 3 weeks. After calcein double labeling the rats were sacrificed and tibial cross sections were prepared from the region with maximal bending at the central diaphysis. Histomorphometry was performed at the entire periosteal and endocortical surface of the tibiae, dividing the periosteum into lateral and medial surfaces. The formation surface was reduced significantly in MIN-H and MIN-VH groups at the medial surface, and in MIN-VH group at the endocortical surface of the loaded tibia (p<0.01 vs. VEH). The mineral appositional rate was reduced significantly in MIN-H and MIN-VH groups at the endocortical surface of the loaded tibia (p<0.01 vs. VEH). The bone formation rate was significantly reduced in MIN-H group at the medial surface, and in MIN-H and MIN-VH groups at the endocortical surface of the loaded tibia (p<0.01 vs. VEH). However, no significant differences were observed in any parameters between the VEH group and either the MIN-L or MIN-M groups for both the loaded and non-loaded tibiae. Based on previous preventive studies in OVX rats, the optimal dose of minodronate for the treatment of osteoporosis would be 0.03 mg/kg (0.21 mg/kg/week). Therefore, we used 0.1mg/kg of minodronate 3 times/week (0.30 mg/kg/week) that was close to 0.21 mg/kg/week. In conclusion, minodronate does not reduce the cortical bone response to mechanical loading at the optimal dose for the treatment of osteoporosis in rat model.


Assuntos
Osso e Ossos/efeitos dos fármacos , Metilidrazinas/farmacologia , Estresse Fisiológico , Animais , Peso Corporal/efeitos dos fármacos , Osso e Ossos/fisiologia , Relação Dose-Resposta a Droga , Feminino , Ratos , Ratos Wistar
10.
Chemotherapy ; 56(1): 71-81, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20299794

RESUMO

BACKGROUND: This study examined, for the first time, the involvement of carnitine deficiency in cardiotoxicity, particularly cyclophosphamide (CP)-induced cardiomyopathy, as well as effects of carnitine supplementation with propionyl-L-carnitine (PLC) on cardiotoxicity. METHODS: An animal model of carnitine deficiency was developed in rats treated with D-carnitine (DC)-mildronate (MD). Adult male Wistar albino rats were assigned to one of six treatment groups: the first three groups were injected intraperitoneally with normal saline, PLC (250 mg/kg/day), and DC (250 mg/kg/day) combined with MD (200 mg/kg/day), respectively, for 10 successive days. In groups 4-6, the same doses of normal saline, PLC and DC-MD were injected, respectively, during the 5 successive days before and after a single dose of CP (200 mg/kg). On day 6 after CP treatment, 24-hour urine was collected, then animals were sacrificed, and serum as well as hearts were isolated. RESULTS: CP caused a significant increase in serum creatine phosphokinase isoenzyme (CK-MB), lactate dehydrogenase (LDH), urinary carnitine excretion and clearance and intramitochondrial acetyl-CoA/CoA-SH, and a significant decrease in serum free carnitine, total carnitine and adenosine triphosphate (ATP) contents in cardiac tissue. In the carnitine-depleted rats, CP induced dramatic increases in CK-MB and LDH levels, carnitine clearance and intramitochondrial acetyl-CoA/CoA-SH, as well as progressive reduction in total carnitine and ATP in cardiac tissues. Interestingly, PLC supplementation completely reversed the biochemical and histopathological changes induced by CP to the control values. CONCLUSION: (1) Carnitine deficiency is a risk factor which is involved in CP-related cardiomyopathy; (2) serum and urinary carnitine levels should be monitored and viewed as indices of CP-induced multiple organ toxicity, and (3) carnitine supplementation, using PLC, prevents the development of CP-induced cardiotoxicity.


Assuntos
Antineoplásicos Alquilantes/toxicidade , Cardiomiopatias/induzido quimicamente , Carnitina/deficiência , Ciclofosfamida/toxicidade , Acetilcoenzima A/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Cardiomiopatias/patologia , Carnitina/análise , Carnitina/metabolismo , Creatina Quinase Forma MB/metabolismo , Modelos Animais de Doenças , L-Lactato Desidrogenase/metabolismo , Masculino , Metilidrazinas/farmacologia , Ratos , Ratos Wistar , Fatores de Risco
11.
Basic Clin Pharmacol Toxicol ; 105(6): 387-94, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19663820

RESUMO

Mildronate is a cardioprotective drug that improves cardiac function during ischaemia and functions by lowering l-carnitine concentration in body tissues and modulating myocardial energy metabolism. The aim of the present study was to characterise cardiovascular function and liver condition after long-term mildronate treatment in rats. In addition, changes in the plasma lipid profile, along with changes in the concentration of mildronate, l-carnitine and gamma-butyrobetaine were monitored in the rat tissues. Wistar rats were perorally treated daily with a mildronate dose of either 100, 200 or 400 mg/kg for 4, 8 or 12 weeks. The l-carnitine-lowering effect of mildronate was dose-dependent. However, the carnitine levels reached a plateau after about four weeks of treatment. During the additional weeks of treatment, the carnitine levels were not considerably changed. The obtained results provide evidence that even a high dose of mildronate does not alter cardiovascular parameters and the function of isolated rat hearts. Furthermore, the histological evaluation of liver tissue cryosections and measurement of biochemical markers of hepatic toxicity showed that all the measured values were within the normal reference range. Our results provide evidence that long-term mildronate administration induces significant changes in carnitine homeostasis, but it is not associated with cardiac impairment or disturbances in liver function.


Assuntos
Fármacos Cardiovasculares/farmacologia , Coração/fisiologia , Fígado/fisiologia , Metilidrazinas/farmacologia , Animais , Betaína/análogos & derivados , Betaína/análise , Betaína/sangue , Biomarcadores/sangue , Glicemia/análise , Peso Corporal/efeitos dos fármacos , Fármacos Cardiovasculares/administração & dosagem , Fármacos Cardiovasculares/sangue , Fármacos Cardiovasculares/toxicidade , Carnitina/análise , Carnitina/sangue , Carnitina O-Palmitoiltransferase/metabolismo , Relação Dose-Resposta a Droga , Glucose/análise , Coração/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Lipídeos/análise , Lipídeos/sangue , Fígado/química , Fígado/efeitos dos fármacos , Fígado/enzimologia , Glicogênio Hepático/análise , Masculino , Metilidrazinas/administração & dosagem , Metilidrazinas/sangue , Metilidrazinas/toxicidade , Miocárdio/química , Miocárdio/enzimologia , Ratos , Ratos Wistar , Fatores de Tempo , Testes de Toxicidade Crônica
12.
Eur J Pharmacol ; 495(1): 67-73, 2004 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-15219822

RESUMO

Mildronate [3-(2,2,2-trimethylhydrazine) propionate (THP)] is an antiischemic drug acting mainly via inhibition of fatty acid beta-oxidation. Some effects of the drug cannot be explained by the latter mechanism. We tested the eventual nitric oxide (NO) dependence of the mildronate action. Mildronate, gamma-butyrobetaine (GBB) and GBB methyl ester induced transient increases in nitric oxide (NO) concentrations in rat blood and myocardium. In vitro, these compounds neither modified the activities of purified neuronal and endothelial recombinant nitric oxide synthases (NOSs) nor were able to interact with their active site. GBB induced vasodilatation at high concentrations only (EC50 = 5 x 10(-5) M) while mildronate alone displayed no vasodilating effect although it enhanced the GBB vasodilating activity. GBB methyl and ethyl esters were found more potent vasodilators (EC50 = 2.5 x 10(-6) M). Pretreatment of aortic rings with NOS inhibitor Nomega-nitro-L-arginine methyl ester (L-NAME) abolished vasodilating effects of the compounds. A hypothesis explaining NO and endothelium-dependent effects of mildronate and its analogues is proposed.


Assuntos
Betaína/análogos & derivados , Betaína/farmacologia , Carnitina/farmacologia , Endotélio/fisiologia , Metilidrazinas/uso terapêutico , Óxido Nítrico/fisiologia , Vasodilatação/fisiologia , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Betaína/antagonistas & inibidores , Betaína/classificação , Carnitina/antagonistas & inibidores , Carnitina/classificação , Ditiocarb/farmacologia , Combinação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Endotélio/efeitos dos fármacos , Masculino , Metilidrazinas/antagonistas & inibidores , Metilidrazinas/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/fisiologia , Isquemia Miocárdica/tratamento farmacológico , Isquemia Miocárdica/prevenção & controle , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico Sintase/efeitos dos fármacos , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo III , Ratos , Ratos Wistar , Vasodilatação/efeitos dos fármacos
13.
Basic Clin Pharmacol Toxicol ; 94(1): 46-50, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14725614

RESUMO

Production of nitric oxide was measured in lipopolysaccharide-treated rats (10 mg/kg, 4 hr) using the electron paramagnetic resonance method. As compared to the control animals, the nitric oxide level in liver of lipopolysaccharide-treated rats increased from 27.6+/-4.7 to 1485+/-129 ng/g tissue, in heart from 4.8+/-0.7 to 271+/-26 ng/g tissue, in blood from 33.6+/-12.4 to 638+/-136 ng/g tissue, in kidney from 3.3+/-0.5 to 356+/-31 ng/g tissue, in brain cortex from 46.0+/-3.4 to 227+/-27 ng/g tissue, in cerebellum from 27.7+/-2.6 to 218+/-30 ng/g tissue, and in testes from 13.8+/-1.1 to 86+/-8 ng/g tissue. Administration of the antiischaemic drug, mildronate (120 mg/kg) caused a significant twofold decrease of the nitric oxide level in brain cortex and cerebellum 1 hr after drug administration. Its natural analogue gamma-butyrobetaine (30 mg/kg) triggered a twofold decrease of the nitric oxide concentration in all studied tissues 30 min. after the administration. Nitric oxide reached the initial level 2 hr later. Neither mildronate nor gamma-butyrobetaine could inhibit the inducible nitric oxide synthase in vitro. Analogues of gamma-butyrobetaine appear to be prospective drugs for the treatment of circulatory complications of sepsis.


Assuntos
Adjuvantes Imunológicos/farmacologia , Betaína/análogos & derivados , Betaína/farmacologia , Carnitina , Lipopolissacarídeos , Metilidrazinas/farmacologia , Óxido Nítrico/biossíntese , Sepse/metabolismo , Animais , Masculino , Ratos , Ratos Wistar
14.
Lik Sprava ; (7): 99-101, 2002.
Artigo em Russo | MEDLINE | ID: mdl-12587322

RESUMO

In the paper, results are reflected of a swimming test in 78 laboratory rats. ATF-LONG has been shown to be capable of augmenting the animals' powers of endurance during loading tests. The established dose-dependent actoprotective activity of ATF-LONG is superior to that of adenosine triphosphate, trimetasidine (preductal), and mildronate. Possible pharmacological mechanisms of its actoprotective activity are discussed. The authors come to the conclusion that performance capability gets improved under exposure to purine nucleotides.


Assuntos
Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/farmacologia , Metabolismo Energético/efeitos dos fármacos , Esforço Físico/efeitos dos fármacos , Animais , Avaliação Pré-Clínica de Medicamentos , Masculino , Metilidrazinas/farmacologia , Condicionamento Físico Animal/fisiologia , Esforço Físico/fisiologia , Ratos , Natação , Trimetazidina/farmacologia
15.
Eksp Klin Farmakol ; 58(2): 44-7, 1995.
Artigo em Russo | MEDLINE | ID: mdl-7773090

RESUMO

Riboxin produces a weak actoprotective effect during exercises, while glucose and benfotiamine enhance this effect of the former. Mildronate fails to affect the development of immune response and suppresses the physical fitness in swimming rats. Mildronate in combination with glucose and benfotiamine normalizes their immunological responsiveness and has no effects on the physical fitness.


Assuntos
Adjuvantes Imunológicos/farmacologia , Metabolismo Energético/efeitos dos fármacos , Esforço Físico/efeitos dos fármacos , Animais , Formação de Anticorpos/efeitos dos fármacos , Glucose/farmacologia , Hipersensibilidade Tardia/imunologia , Hipersensibilidade Tardia/metabolismo , Imunização , Inosina Difosfato/farmacologia , Metilidrazinas/farmacologia , Esforço Físico/fisiologia , Ratos , Ratos Wistar , Natação , Tiamina/análogos & derivados , Tiamina/farmacologia
16.
Eksp Klin Farmakol ; 55(6): 33-5, 1992.
Artigo em Russo | MEDLINE | ID: mdl-1305872

RESUMO

With the use of the erythrocyte osmotic and acidic resistance methods, the experiments on intact albino rats by applying a model of chronic non-specific lung diseases and those in vitro have shown that mildronate has a membrane-stabilizing action only when given in high doses (500 mg/kg) and concentrations (10(-3)-10(-4) M). When used in low doses (5, 25, 50, and 200 mg/kg) and concentrations (10(-5)-10(-7) M), in produces no positive effect.


Assuntos
Fármacos Cardiovasculares/uso terapêutico , Permeabilidade da Membrana Celular/efeitos dos fármacos , Membrana Eritrocítica/efeitos dos fármacos , Pneumopatias Obstrutivas/tratamento farmacológico , Metilidrazinas/uso terapêutico , Animais , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Técnicas In Vitro , Pneumopatias Obstrutivas/sangue , Masculino , Metilidrazinas/farmacologia , Fragilidade Osmótica/efeitos dos fármacos , Ratos , Fatores de Tempo
17.
Kardiologiia ; 31(1): 17-9, 1991 Jan.
Artigo em Russo | MEDLINE | ID: mdl-2046238

RESUMO

In experiments on dogs, application of the cross-over circulation method revealed that mildronate increased coronary blood flow due to active coronary dilation. In experiments on cats, a cardioprotective effect of mildronate was found, which prevented the development of acute ischemic heart failure by stabilizing the major hemodynamic parameters. Clinical studies of patients with Functional Classes I-III angina provided evidence for positive effects of mildronate on coronary blood flow.


Assuntos
Circulação Coronária/efeitos dos fármacos , Doença das Coronárias/tratamento farmacológico , Metilidrazinas/farmacologia , Vasodilatadores/farmacologia , Adulto , Idoso , Animais , Circulação Coronária/fisiologia , Doença das Coronárias/fisiopatologia , Cães , Avaliação Pré-Clínica de Medicamentos , Humanos , Masculino , Metilidrazinas/uso terapêutico , Pessoa de Meia-Idade , Vasodilatadores/uso terapêutico
18.
Jpn Heart J ; 30(5): 743-50, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2614934

RESUMO

The cardiac effects of mildronate were studied in isolated and blood-perfused atrial and ventricular preparations from mongrel dogs. Mildronate (10(-9)-10(-6) mol) did not induce any chronotropic or inotropic responses in spontaneously beating isolated right atria at 37 degrees C. However, it produced negative chronotropic and inotropic effects at large doses (10(-5)-10(-4) mol). Mildronate-induced responses were not significantly inhibited by treatment with atropine, suggesting that they do not involve muscarinic mechanisms. Mildronate produced only a slight negative inotropic effect in electrically paced, isolated left ventricular preparations at extremely large doses. Intravenous injections of 10(-4) mol/kg mildronate to the support (donor) dog induced a slight, non-significant, depressor effect, and did not significantly influence either atrial pacemaker activity or atrial developed tension. From these results, it is concluded that a therapeutic dose of mildronate has no direct influence on SA nodal pacemaker activity and atrial contractility, but that it has a slight cardiac depressant property at large doses.


Assuntos
Frequência Cardíaca/efeitos dos fármacos , Coração/efeitos dos fármacos , Metilidrazinas/farmacologia , Contração Miocárdica/efeitos dos fármacos , Animais , Função Atrial , Atropina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Carbacol/farmacologia , Depressão Química , Cães , Feminino , Coração/fisiologia , Átrios do Coração/efeitos dos fármacos , Ventrículos do Coração/efeitos dos fármacos , Técnicas In Vitro , Masculino , Metilidrazinas/administração & dosagem , Perfusão/métodos , Função Ventricular
19.
Farmakol Toksikol ; 52(5): 24-7, 1989.
Artigo em Russo | MEDLINE | ID: mdl-2599072

RESUMO

The effects of carnitine and its structural analogue 3-(2,2,2-trimethylhydrazine) propionate (THP) were studied in rats with experimental myocardial infarction caused by occlusion of the left descending branch of the coronary artery. After one day in the group of untreated animals the relative lethality was 40.3 +/- 10.5%, the size of the infarction zone was 29.8 +/- 2.0%. Carnitine and THP decreased on the average twice the parameters as well as lactate level in the myocardium. THP prevented a reduction of ATP and AMP levels by 35 and 37%, respectively, and a decrease of adenine nucleotide pool by 30%. In this case carnitine was ineffective. It is suggested that inhibition of beta-oxidation of fatty acids by THP is energetically more beneficial for the myocardium during regional ischemia than substitution therapy with carnitine.


Assuntos
Fármacos Cardiovasculares/uso terapêutico , Carnitina/uso terapêutico , Doença das Coronárias/tratamento farmacológico , Metabolismo Energético/efeitos dos fármacos , Coração/efeitos dos fármacos , Metilidrazinas/uso terapêutico , Animais , Fármacos Cardiovasculares/farmacologia , Carnitina/farmacologia , Doença das Coronárias/metabolismo , Doença das Coronárias/mortalidade , Avaliação Pré-Clínica de Medicamentos , Masculino , Metilidrazinas/farmacologia , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/mortalidade , Miocárdio/metabolismo , Ratos
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