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1.
Can J Physiol Pharmacol ; 91(11): 966-72, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24117265

ABSTRACT

Pharmacological preconditioning (PPC) with mitochondrial ATP-sensitive K(+) channel openers such as diazoxide, provides protection against ischemia in cardiac muscle, skeletal muscle, and other tissues. Effects on Ca(2+) homeostasis during the late phase of PPC have been described in cardiomyocytes, but no information is available regarding intracellular Ca(2+) changes in skeletal muscle fibers during late PPC. Intracellular Ca(2+) signals were measured in single fibers of adult mouse skeletal muscle, with fluorescent probes, 48 h after the administration of diazoxide. Parvalbumin levels in the myofibers were quantitated by Western blot. Diazoxide induction of late PPC was confirmed by partial protection of muscles from peroxide-induced damage. Late PPC was associated with a significant decrease in the duration of Ca(2+) signals during single twitches and tetanus with no changes in peak values. This effect was prevented by the reactive oxygen species (ROS) scavenger tiron. Late PPC was accompanied by a 30% increase in parvalbumin levels, and this effect was also blocked by tiron. Our data show, for the first time, a role of parvalbumin in late PPC in skeletal muscle.


Subject(s)
KATP Channels/agonists , Muscle, Skeletal/drug effects , Parvalbumins/biosynthesis , Algorithms , Aniline Compounds , Animals , Blotting, Western , Calcium/metabolism , Calcium Signaling/drug effects , Calcium-Calmodulin-Dependent Protein Kinase Type 2/antagonists & inhibitors , Calcium-Calmodulin-Dependent Protein Kinase Type 2/metabolism , Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors , Cyclic AMP-Dependent Protein Kinases/metabolism , Diazoxide/pharmacology , Electric Stimulation , Fluorescent Dyes , Homeostasis/drug effects , Male , Mice , Mice, Inbred BALB C , Muscle Fibers, Skeletal/drug effects , Protein Kinase Inhibitors/pharmacology , Reactive Oxygen Species , Sarcoplasmic Reticulum Calcium-Transporting ATPases/metabolism , Xanthenes
2.
J Nat Med ; 63(4): 393-401, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19484331

ABSTRACT

Astianthus viminalis has been used as a medicinal plant for a long time owing to its many physiological actions such as anti-inflammatory and antidiabetic activities. A new tetracyclic triterpenoid 3beta,19alpha-dihydroxyurs-12,20(21)-diene-28-oic acid (1), known constituents oleanolic acid (2) and ursolic acid (3), and the coumarins 7,8-dimethoxycoumarin (4) and 7-methoxycoumarin (5) were isolated from the chloroform extract of the leaves of A. viminalis. The structure and relative configurations of 1 were determined by spectroscopic methods (1H- and 13C-NMR, IR, and MS) and 2D-NMR experiments. The hypoglycemic ingredients of A. viminalis were characterized as compounds 1-3. The hypoglycemic effect of the isolated natural product 1 was investigated in normoglycemic and streptozotocin (STZ)-induced diabetic mice. All effects were compared with those of tolbutamide. Triterpenoid 1 showed potent hypoglycemic and hypolipidemic effects in the STZ-induced diabetic mice. Continuous administration of 1 (30 mg/kg, orally) led to significant decrease in the level of glucose, triglycerides, total cholesterol, LDL, and VLDL in the diabetic mice, whereas the level of HDL did not alter significantly in any of the groups studied.


Subject(s)
Hypoglycemic Agents/pharmacology , Plant Extracts/pharmacology , Plants, Medicinal/chemistry , Animals , Blood Glucose/drug effects , Coumarins/chemistry , Diabetes Mellitus, Experimental/drug therapy , Female , Hypoglycemic Agents/chemistry , Magnetic Resonance Spectroscopy , Male , Mice , Plant Extracts/chemistry , Triterpenes/chemistry , Triterpenes/pharmacology , Ursolic Acid
3.
J Nat Med ; 63(1): 65-8, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18665331

ABSTRACT

The antispasmodic effects of hexane-, chloroform-, methanol- and water-extracts of the orchid Encyclia michuacana were studied in vitro on guinea pig ileum against three spasmogens: acetylcholine (Ach), histamine and barium chloride. The chloroform extract exerted a significant antispasmodic effect on ileum contractions induced by Ach, histamine and barium chloride (IC(50) = 90.64, 73.12 and 115.2 microg/mL, respectively). Furthermore, the chloroform extract of E. michuacana provoked a concentration-dependent inhibition of spontaneous contractions of guinea pig ileum with potencies comparable to those of papaverine. The antagonism against the spasmogens used suggests that the action of the chloroform extract of E. michuacana could be due mainly to the presence of gigantol. Hexane-, methanol- and water-extracts did not elicit any significant spasmolytic activity.


Subject(s)
Ileum/drug effects , Muscle Relaxation/drug effects , Orchidaceae/chemistry , Parasympatholytics/pharmacology , Plant Extracts/pharmacology , Animals , Guinea Pigs , Ileum/physiology , In Vitro Techniques , Molecular Structure , Parasympatholytics/chemistry , Plant Extracts/chemistry
4.
J Nat Med ; 62(3): 328-31, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18404301

ABSTRACT

Two abietane diterpenes were isolated from cyanobacteria Microcoleous lacustris, 20-nor-3alpha-acetoxyabieta-5,7,9,11,13-pentaene and 20-nor-3alpha-acetoxy-12-hydroxy-abieta-5,7,9,11,13-pentaene. These compounds were assayed against Staphylococcus aureus, Staphylococcus epidermidis, Salmonella typhi, Vibrio cholerae, Bacillus subtilis, Bacillus cereus, Escherichia coli, and Klebsiella pneumoniae. Both compounds showed activity against S. aureus, S. epidermidis, S. typhi, and V. cholerae, but not against the other bacteria.


Subject(s)
Abietanes/pharmacology , Anti-Bacterial Agents/pharmacology , Cyanobacteria/chemistry , Abietanes/isolation & purification , Anti-Bacterial Agents/isolation & purification , Bacteria/drug effects , Microbial Sensitivity Tests
5.
J Ethnopharmacol ; 117(1): 1-27, 2008 Apr 17.
Article in English | MEDLINE | ID: mdl-18353572

ABSTRACT

Psidium guajava, is an important food crop and medicinal plant in tropical and subtropical countries is widely used like food and in folk medicine around of the world. This aims a comprehensive of the chemical constituents, pharmacological, and clinical uses. Different pharmacological experiments in a number of in vitro and in vivo models have been carried out. Also have been identified the medicinally important phyto-constituents. A number of metabolites in good yield and some have been shown to possess useful biological activities belonging mainly to phenolic, flavonoid, carotenoid, terpenoid and triterpene. Extracts and metabolites of this plant, particularly those from leaves and fruits possess useful pharmacological activities. A survey of the literature shows P. guajava is mainly known for its antispasmodic and antimicrobial properties in the treatment of diarrhoea and dysentery. Has also been used extensively as a hypoglycaemic agent. Many pharmacological studies have demonstrated the ability of this plant to exhibit antioxidant, hepatoprotection, anti-allergy, antimicrobial, antigenotoxic, antiplasmodial, cytotoxic, antispasmodic, cardioactive, anticough, antidiabetic, antiinflamatory and antinociceptive activities, supporting its traditional uses. Suggest a wide range of clinical applications for the treatment of infantile rotaviral enteritis, diarrhoea and diabetes.


Subject(s)
Phytotherapy , Plant Extracts/pharmacology , Psidium , Clinical Trials as Topic , Humans , Medicine, Traditional , Plant Extracts/therapeutic use , Plant Extracts/toxicity , Psidium/chemistry
6.
Phytother Res ; 20(7): 542-5, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16619344

ABSTRACT

The methanol soluble fraction of the leaves of Buddleia scordioides after column chromatography resulted in the isolation of two known iridoid glucosides, catalpol and methylcatalpol. The structures were elucidated by extensive 1D-2D-NMR spectroscopy. The structure of methylcatalpol was confirmed by single-crystal x-ray diffraction. These compounds showed protective activity against increased (both chloroform and histamine) skin vascular permeability in rabbits. The protective effect was measured as the reduction in leakage of Evans blue. The results showed that the iridoids produced a significant inhibition of microvascular permeability. A comparison was made between the action of the iridoids and a known inhibitor of vascular permeability, troxerutin (50 mg/kg). Methylcatalpol and catalpol were found to be less effective than troxerutin.


Subject(s)
Buddleja/chemistry , Capillaries/drug effects , Capillaries/physiology , Glucosides/pharmacology , Iridoids/pharmacology , Permeability/drug effects , Animals , Glucosides/chemistry , Hydroxyethylrutoside/analogs & derivatives , Hydroxyethylrutoside/pharmacology , Iridoid Glucosides , Iridoids/chemistry , Male , Rabbits , Skin/blood supply , Vasoconstrictor Agents/chemistry , Vasoconstrictor Agents/pharmacology
7.
Eur J Immunol ; 35(1): 16-24, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15580659

ABSTRACT

Killer-cell Ig-like receptors (KIR) are structurally and functionally diverse, and enable human NK cells to survey the expression of individual HLA class I molecules, often altered in infections and tumors. Multiple events of non-reciprocal recombination have contributed to the rapid diversification of KIR. We show that approximately 4.5% of the individuals of a Caucasoid population bear a recombinant allele of KIR3DP1, officially designed KIR3DP1*004, that associates tightly with gene duplications of KIR3DP1, KIR2DL4 and KIR3DL1/KIR3DS1. The KIR3DP1 gene is normally silent, but the recombinant allele carries a novel promoter sequence and, as a consequence, is transcribed in all tested individuals. Messenger RNA of KIR3DP1*004 is made up of six exons; of these, exons 1-5 are similar to, and spliced like, those encoding the leader peptide and Ig-domains of KIR3D. By contrast, exon 6 is homologous to no other human KIR sequence, but only to possible homologs in chimpanzees and rhesus macaques, and encodes a short hydrophilic tail. The putative KIR3DP1*004 product, like those of the related genes LAIR-2 and LILRA3/ILT6/LIR4, is predicted to be secreted to the extracellular medium rather than anchored to the cell membrane.


Subject(s)
Receptors, Immunologic/genetics , Alleles , Amino Acid Sequence , Gene Duplication , Gene Silencing , Haplotypes , Humans , Killer Cells, Natural/immunology , Molecular Sequence Data , Phylogeny , Protein Structure, Tertiary , Receptors, Immunologic/biosynthesis , Receptors, Immunologic/chemistry , Receptors, KIR , Receptors, KIR2DL4 , Receptors, KIR3DL1 , Receptors, KIR3DS1 , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics , Recombination, Genetic , Sequence Homology, Amino Acid , Transcription, Genetic
8.
Vet. Méx ; 28(3): 209-13, jul.-sept. 1997. tab
Article in Spanish | LILACS | ID: lil-227437

ABSTRACT

En el presente trabajo se han determinado las concentraciones plasmáticas de proteínas totales e inmunoglobulinas mediante inmunodifusión radial, en 40 caballos de Pura Raza Española, de la provincia de Córdoba, España. Los niveles medios obtenidos son similares a los determinados anteriormente para la especie equina, en cambio se pueden encontrar variaciones en cuanto a los niveles medios de inmunoglobulinas plasmáticas con respecto a otras raza, con un valor medio para la IgG de 1293.55ñ77.39 mg/dl, para la IgGT 105.17ñ145.03 mg/dl, para la IgM 56.39ñ5.38 mg/dl y para la IgA 44.92ñ3.525 mg/dl. El sexo y la edad modifican los niveles medios de algunas de estas inmunoglobulinas


Subject(s)
Animals , Plasma , Horses , Proteins , Immunologic Deficiency Syndromes
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