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1.
iScience ; 27(4): 109468, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38550985

RESUMO

Nutraceutical approaches to promote adipose tissue thermogenesis may help to prevent obesity onset. Creatine is a critical regulator of adipose metabolic function and low-dose lithium supplementation has been shown to promote adipose thermogenesis. In the present study, we sought to directly compare the two supplements for their effects on adipose metabolism and thermogenesis. We show that both supplements increase daily energy expenditure (EE) and reduce body mass in male Sprague-Dawley rats. Lithium increased brown adipose tissue (BAT) mitochondrial and lipolytic proteins that are associated with thermogenesis, while creatine increased BAT UCP1 and mitochondrial respiration. The BAT thermogenic findings were not observed in females. White adipose tissue and skeletal muscle markers of thermogenesis were unaltered with the supplements. Together, the data show that low-dose lithium and creatine have diverging effects on markers of BAT thermogenesis and that each increase daily EE and lower body mass in a sex-dependent manner.

2.
Am J Physiol Cell Physiol ; 326(3): C999-C1009, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38344799

RESUMO

Dysregulation of skeletal muscle morphology and metabolism is associated with chronic diseases such as obesity and type 2 diabetes. The enzyme glycogen synthase kinase 3 (GSK3) is highly involved in skeletal muscle physiology and metabolism, acting as a negative regulator of muscle size, strength, adaptive thermogenesis, and glucose homeostasis. Correspondingly, we have shown that partial knockdown (∼40%) of GSK3 specifically in skeletal muscle increases lean mass, reduces fat mass, and activates muscle-based adaptive thermogenesis via sarco(endo)plasmic reticulum Ca2+ (SERCA) uncoupling in male mice. However, the effects of GSK3 knockdown in female mice have yet to be investigated. Here, we examined the effects of muscle-specific GSK3 knockdown on body composition, muscle size and strength, and whole body metabolism in female C57BL/6J mice. Our results show that GSK3 content is higher in the female soleus versus the male soleus; however, there were no differences in the extensor digitorum longus (EDL). Furthermore, muscle-specific GSK3 knockdown did not alter body composition in female mice, nor did it alter daily energy expenditure, glucose/insulin tolerance, mitochondrial respiration, or the expression of the SERCA uncouplers sarcolipin and neuronatin. We also did not find any differences in soleus muscle size, strength, or fatigue resistance. In the EDL, we found that an increase in absolute and specific force production, but there were no differences in fatigability. Therefore, our study highlights sex differences in the response to genetic reduction of gsk3, with most of the effects previously observed in male mice being absent in females.NEW & NOTEWORTHY Here we show that partial GSK3 knockdown has minimal effects on whole body metabolism and muscle contractility in female mice. This is partly inconsistent with previous results found in male mice, which reveal a potential influence of biological sex.


Assuntos
Diabetes Mellitus Tipo 2 , Quinase 3 da Glicogênio Sintase , Camundongos , Feminino , Masculino , Animais , Diabetes Mellitus Tipo 2/metabolismo , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Glucose/metabolismo
3.
Biochim Biophys Acta Mol Cell Res ; 1864(4): 708-718, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27993671

RESUMO

Autophagy is a catabolic process that targets and degrades cytoplasmic materials. In skeletal muscle, autophagy is required for the control of mass under catabolic conditions, but is also basally active in the maintenance of myofiber homeostasis. In this study, we found that some specific autophagic markers (LC3-I, LC3-II, SQSTM1) were basally lower in glycolytic muscle compared to oxidative muscle of autophagy competent mice. In contrast, basal autophagic flux was higher in glycolytic muscle. In addition, we used several skeletal muscle-specific Atg7 transgenic mouse models to investigate the effect of acute (iAtg7-/-) and chronic (cAtg7-/-) autophagy deficiency on skeletal muscle morphology, contractility, and apoptotic signaling. While acute autophagy ablation (iAtg7-/-) resulted in increased centralized nuclei in glycolytic muscle, it did not alter contractile properties or measures of apoptosis and proteolysis. In contrast, with chronic autophagy deficiency (cAtg7-/-) there was an increased proportion of centralized nuclei, as well as reduced force and altered twitch kinetics in glycolytic muscle. Glycolytic muscle of cAtg7-/- mice also displayed an increased level of the pro-apoptotic protein BAX, as well as calpain and proteasomal enzymatic activity. Collectively, our data demonstrate cumulative damage from chronic skeletal muscle-specific autophagy deficiency with associated apoptotic and proteasomal upregulation. These findings point towards the importance of investigating different muscle/fiber types when studying skeletal muscle autophagy, and the critical role of autophagy in the maintenance of myofiber function, integrity, and cellular health.


Assuntos
Proteína 7 Relacionada à Autofagia/genética , Autofagia/genética , Células Musculares/metabolismo , Músculo Esquelético/metabolismo , Proteína X Associada a bcl-2/metabolismo , Animais , Apoptose , Proteína 7 Relacionada à Autofagia/deficiência , Calpaína/genética , Calpaína/metabolismo , Núcleo Celular/metabolismo , Núcleo Celular/ultraestrutura , Regulação da Expressão Gênica , Glicólise/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Células Musculares/patologia , Contração Muscular , Músculo Esquelético/patologia , Fosforilação Oxidativa , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Proteína Sequestossoma-1/genética , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais , Proteína X Associada a bcl-2/genética
4.
Poult Sci ; 88(3): 669-79, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19211540

RESUMO

Polymerase chain reaction-RFLP analysis has been applied to the identification of meats from quail (Coturnix coturnix), pheasant (Phasianus colchicus), red-legged partridge (Alectoris rufa), chukar partridge (Alectoris chukar), guinea fowl (Numida meleagris), capercaillie (Tetrao urogallus), Eurasian woodcock (Scolopax rusticola), and woodpigeon (Columba palumbus). Polymerase chain reaction amplification was carried out using a set of primers flanking a conserved region of approximately 310 bp from the mitochondrial D-loop region. Restriction site analysis based on sequence data from this DNA fragment permitted the selection of HinfI, MboII, and Hpy188III endonucleases for species identification. The restriction profiles obtained when amplicons were digested with the chosen enzymes allowed the unequivocal identification of all game bird species analyzed. Consistent results were obtained with both raw and heat-processed meats.


Assuntos
DNA Mitocondrial/genética , Carne/análise , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição/genética , Animais , Sequência de Bases , Culinária , Galliformes/genética , Especificidade da Espécie
5.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 10): o2330, 2009 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-21577801

RESUMO

THE TITLE COMPOUND (SYSTEMATIC NAME: 9a-hydr-oxy-3,4a,5-trimethyl-4a,6,7,8a,9,9a-hexa-hydro-4H,5H-naphtho[2,3-b]furan-2,8-dione), C(15)H(20)O(4), is a sesquiterpene lactone showing the typical eremophilanolide skeleton, which has been isolated from the plant Senecio candidans collected in the Chilean Magallanes region. The present study confirms the atomic connectivity assigned on the basis of (1)H and (13)C NMR spectroscopy, as well as the relative stereochemistry of the 4α-methyl,5α-methyl,8ß-hydr-oxy,10ß-H unit. The crystal structure is stabilized by inter-molecular O-H⋯O hydrogen bonds involving the hydr-oxy group as donor and the oxo group as acceptor, giving chains along the a axis. The absolute structure was not determined because of the lack of suitable anomalous scatters.

6.
J Anim Sci ; 85(10): 2734-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17565058

RESUMO

A PCR method based on the nucleotide sequence variation in the 12S ribosomal RNA, mitochondrial gene has been developed for the specific and qualitative detection and identification of cat, dog, and rat or mouse tissue in food and feedstuffs. The primers designed generated specific fragments of 108, 101, and 96 bp in length for cat, dog, and rat or mouse tissues, respectively. Specificity of the primers was tested against 32 nontarget species including mammals, birds, fish, and plant species. This PCR method allowed detection of raw and heated cat, dog, and rat or mouse tissues in meat/oats mixtures even when the concentration of the target species was reduced to 0.1%. Furthermore, the performance of the method was not affected by prolonged heat-treatment (up to 133 degrees C for 20 min at 300 kPa), and consequently, it could be very useful to verify the origin of raw materials in food and feedstuffs submitted to denaturing technologies, for which other methods cannot be applied.


Assuntos
Ração Animal/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Reação em Cadeia da Polimerase/veterinária , RNA Ribossômico/análise , Animais , Gatos , Cães , Temperatura Alta , Camundongos , Peso Molecular , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/normas , RNA Ribossômico/genética , Ratos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Especificidade da Espécie
7.
J Anim Sci ; 85(2): 452-8, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17235030

RESUMO

PCR method was applied for the qualitative identification of chicken (Gallus gallus), turkey (Meleagris gallipavo), duck (Anas platyrhynchos x Cairina muschata), and goose (Anser anser) tissues in feed-stuffs, on an individual basis. The assay uses oligonucleotide primers that are specific for each avian species, targeting the 12S rRNA mitochondrial gene. The primers designed generated amplicons of 95, 122, 64, and 98 bp length for chicken, turkey, duck, and goose, respectively. The specificity of the primers was tested against 29 animal species including mammals, birds, and fish, as well as 8 plant species. Analysis of experimental feedstuffs demonstrated the detection of each target species in the range of 0.1 to 100%. The performance of this method was not affected by prolonged heat-treatment (up to 133 degrees C for 20 min at 300 kPa), and consequently, it could be very useful for the accurate identification of tissues from these 4 avian species in products submitted to denaturing technologies, for which other methods cannot be applied.


Assuntos
Ração Animal/análise , Análise de Alimentos/métodos , Reação em Cadeia da Polimerase/veterinária , Aves Domésticas/genética , Animais , DNA/análise , Primers do DNA/química , Temperatura Alta , NADH Desidrogenase/genética , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico/genética , Sensibilidade e Especificidade , Especificidade da Espécie
8.
Meat Sci ; 76(4): 644-52, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22061240

RESUMO

A polymerase chain reaction (PCR) assay was developed for the identification of meats from chamois (Rupicapra rupicapra), pyrenean ibex (Capra pyrenaica), and mouflon (Ovis ammon) by using oligonucleotides targeting mitochondrial D-loop sequences. A D-loop region (∼700-1000 bp) was firstly amplified and sequenced from various game and domestic meat DNAs, and three primer sets were then designed on the basis of nucleotide multialignment of the generated D-loop sequences. As expected from sequence analysis, PCR amplification of the targeted D-loop fragments was successfully achieved from chamois (88 bp), pyrenean ibex (178 bp), and mouflon (155 bp) meats, showing adequate specificity and reproducibility against a number of game and domestic meats. Mouflon and sheep meats were amplified together in accordance to the high nucleotide identity of their mt D-loop sequences. In this work, satisfactory amplification was also accomplished in the analysis of experimentally pasteurized (72°C for 30min) and sterilized (121°C for 20min) meats, with a detection limit of ∼0.1% for each of the targeted species. The proposed PCR assay represents a rapid and straightforward method for the detection of possible adulterations in game meat products.

9.
Meat Sci ; 76(2): 234-40, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22064291

RESUMO

Polymerase chain reaction (PCR) based on oligonucleotide primers targeting the mitochondrial 12S rRNA gene was applied to the specific identification of meats from red deer (Cervus elaphus), fallow deer (Dama dama), and roe deer (Capreolus capreolus). The use of a common reverse primer, together with forward specific primers for red deer, fallow deer, and roe deer, allowed the selective amplification of the desired cervid sequences. The specificity of each primer pair was verified by PCR analysis of DNA from various game and domestic meats. The assay can be useful for the accurate identification of meats from cervid species, avoiding mislabeling or fraudulent species substitution in meat products.

10.
J Dairy Sci ; 88(9): 3115-20, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16107400

RESUMO

The polymerase chain reaction has been applied for the specific detection of goats' milk in sheep's milk using primers targeting the mitochondrial 12S ribosomal RNA gene. The use of goat-specific primers yielded a 122-bp fragment from goats' milk DNA, whereas no amplification signal was obtained in sheep's, cows', and water buffaloes' milk DNA. Polymerase chain reaction analysis of raw and heat-treated milk binary mixtures of sheep/goat enabled the specific detection of goats' milk with a sensitivity threshold of 0.1%. This study demonstrates the usefulness of the proposed polymerase chain reaction assay for authentication of milk products in routine analysis.


Assuntos
Contaminação de Alimentos/análise , Cabras/genética , Leite/química , Reação em Cadeia da Polimerase , Ovinos , Animais , Búfalos , DNA/análise , Eletroforese em Gel de Ágar , Feminino , Manipulação de Alimentos , Temperatura Alta , RNA/genética , RNA Mitocondrial , RNA Ribossômico/genética
11.
J Dairy Sci ; 87(9): 2839-45, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15375042

RESUMO

A polymerase chain reaction (PCR) assay was developed for the specific identification of cows' milk in sheep's and goats' milk by using primers targeting the mitochondrial 12S rRNA gene. The use of a forward primer complementary to a conserved DNA sequence, along with a reverse primer specific for cow, yielded a 223-bp fragment from cows' milk DNA, whereas no amplification signal was obtained in sheep's and goats' milk DNA. The technique was applied to raw, pasteurized, and sterilized milk binary mixtures of cow-sheep and cow-goat, enabling the specific detection of cows' milk with a good sensitivity threshold (0.1%). The proposed PCR assay represents a rapid and straightforward method applicable to the authentication of milk and other dairy products in routine analysis.


Assuntos
Bovinos/genética , Contaminação de Alimentos/análise , Cabras , Leite/química , Reação em Cadeia da Polimerase/métodos , Ovinos , Animais , DNA Mitocondrial/análise , Temperatura Alta , RNA Ribossômico/genética , Sensibilidade e Especificidade , Especificidade da Espécie
12.
Fitoterapia ; 72(6): 680-5, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11543969

RESUMO

Alcoholic extracts of seven plants belonging to the Solanaceae family were phytochemically screened and evaluated for their cytotoxic activity by Brine Shrimp Test (BST) with Artemia salina larvae, Inhibition of Cell Division Test (ICDT) on sea urchin Loxechinus albus fertilized eggs and inhibition of crown gall tumors on Potato Disk Bioassay (PDB). From Salpichroa diffusa, bioassay-guided chromatographic separation afforded some active fractions from which epi-katonic acid was identified.


Assuntos
Artemia/efeitos dos fármacos , Medicina Tradicional , Extratos Vegetais/toxicidade , Rhizobium/efeitos dos fármacos , Ouriços-do-Mar/efeitos dos fármacos , Solanaceae , Animais , Feminino , Humanos , Larva/efeitos dos fármacos , Dose Letal Mediana , Masculino , Fitoterapia , Tumores de Planta , Solanum tuberosum , América do Sul
13.
J Nat Prod ; 64(1): 6-11, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11170657

RESUMO

Three eremophilanolides, 1alpha-acetoxy-8beta-methoxy-10betaH-eremophil-7(11)-en-8alpha,12-olide (1); 1alpha-angeloyloxy-6beta-hydroxy-8beta-methoxy-10betaH-eremophil-7(11)-en-8alpha,12-olide (2); and 1alpha-angeloyloxy-8betaH,10betaH-eremophil-7(11)-en-8alpha,12-olide (3), and two pyrrolizidine alkaloids, integerrimine (4) and its N-oxide (5), were isolated from bioactive fractions of Senecio miser. The structures of the new compounds 1 and 2 were established by NMR spectroscopic analysis and chemical transformation. The X-ray analysis of compound 1 was also performed. Eremophilanolides 1 and 2 and alkaloids 4 and 5 were found to be strong insect antifeedants, further supporting a proposed defensive role for these classes of compounds.


Assuntos
Fungicidas Industriais/química , Inseticidas/química , Naftalenos/química , Plantas Tóxicas , Alcaloides de Pirrolizidina/química , Senécio/química , Animais , Afídeos , Chile , Besouros , Cristalografia por Raios X , Comportamento Alimentar/efeitos dos fármacos , Fungicidas Industriais/isolamento & purificação , Fungicidas Industriais/farmacologia , Fusarium/efeitos dos fármacos , Hemolinfa/efeitos dos fármacos , Inseticidas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Naftalenos/isolamento & purificação , Naftalenos/farmacologia , Extratos Vegetais/farmacologia , Sesquiterpenos Policíclicos , Alcaloides de Pirrolizidina/isolamento & purificação , Alcaloides de Pirrolizidina/farmacologia , Sesquiterpenos , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Spodoptera
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