RESUMO
The melanocortin-3 receptor (MC3R) is a member of the G protein-coupled receptor superfamily that plays a critical role in controlling energy balance and metabolism. Although pharmacological characterization of MC3R has been reported previously in several other species, there is no report on the MC3R from giant panda (Ailuropoda melanoleuca). This ancient species is known as a 'living fossil' and is among the most endangered animals in the world. Giant panda survive on a specialized diet of bamboo despite possessing a typical carnivorous digestive system. We report herein the molecular cloning and pharmacological characterization of amMC3R. Homology and phylogenetic analysis showed that amMC3R was highly homologous (>85%) to several other mammalian MC3Rs. Using human MC3R (hMC3R) as a control, the binding of five agonists, [Nle4, D-Phe7]-α-melanocyte stimulating hormone (NDP-MSH), α-, ß-, γ-, and D-Trp8-γ-MSH, was investigated, as well as Gs-cAMP and pERK1/2 signaling. The results showed that amMC3R bound NDP- and D-Trp8-γ-MSH with the highest affinity, followed by α-, ß-, and γ-MSH, with the same rank order as hMC3R. When stimulated with agonists, amMC3R displayed increased intracellular cAMP and activation of pERK1/2. These data suggest that the cloned amMC3R was a functional receptor. The availability of amMC3R and knowledge of its pharmacological functions will assist further investigation of its role in controlling energy balance and metabolism.
Assuntos
Receptor Tipo 3 de Melanocortina/metabolismo , Ursidae/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , AMP Cíclico/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células HEK293 , Humanos , Ligantes , Fosforilação , Filogenia , Receptor Tipo 3 de Melanocortina/agonistas , Receptor Tipo 3 de Melanocortina/química , Transdução de SinaisRESUMO
It was found that Hg(2+) can inhibit the peroxidase mimetic activity of bovine serum albumin (BSA) protected Au clusters (BSA-Au) due to the specific interaction between Hg(2+) and Au(+) existed onto the surface of BSA-Au clusters. By coupling with 3, 3', 5, 5'-tetramethylbenzidine (TMB)-H2O2 chromogenic reaction, a novel method for Hg(2+) detection was developed based on the inhibiting effect of Hg(2+) on BSA-Au clusters peroxidase-like activity. This method exhibited high selectivity and sensitivity. As low as 3 nM (0.6 ppb, 3σ) Hg(2+) could be detected with a linear range from 10 nM (2 ppb) to 10 µM (2 ppm) and this method was successfully applied for the determination of total mercury content in skin lightening products.
Assuntos
Ouro/química , Mercúrio/análise , Nanopartículas Metálicas/química , Soroalbumina Bovina/química , Preparações Clareadoras de Pele/química , Benzidinas/química , Materiais Biomiméticos , Contaminação de Medicamentos , Humanos , Peróxido de Hidrogênio/química , Oxirredução , Peroxidase/química , Sensibilidade e EspecificidadeRESUMO
Because amyloidogenic proteins, such as prion protein, ß-amyloid peptide and α-synuclein, are associated with a variety of diseases, methods for their detection are important. Recombinant prion protein (rPrP) can selectively induce aggregation of dihydrolipoic acid capped gold nanoparticles (DHLA-AuNPs), which reduces the absorbance of the DHLA-AuNPs and changes their color from red to blue. These changes were used for label-free qualitative and quantitative detection of amyloidogenic protein. The addition of NaCl improved the detection sensitivity considerably, and the detection limit was as low as 33 pmol/L.
Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas/química , Príons/sangue , Ácido Tióctico/análogos & derivados , Animais , Bovinos , Cor , Escherichia coli/química , Ouro/química , Humanos , Limite de Detecção , Cloreto de Sódio/química , Espectrofotometria , Ácido Tióctico/químicaRESUMO
OBJECTIVE: To observe the clinical therapeutic effect of the needling method for regulating wei and strengthening brain on insomnia. METHODS: Two hundred cases of insomnia were randomly divided into a test group and a control group, 100 cases in each group. The test group were treated with the needling method for regulating wei and strengthening brain with Baihui (GV 20), Dazhui (GV 14), Shenmai (BL 62), Zhaohai (KI 6) and ear points Yuanzhong, Shenmen selected; and in the control group, Sishencong (EX-HN 1), Shenmen (HT 7) and Sanyinjiao (SP 6) were selected. Acupuncture was given once daily for 15 days. Pittsburgh sleep quality index (PSQI) was used for scoring before and after treatment. RESULTS: The total effective rate was 89.0% in the test group and 65.0% in the control group with a very significant difference between the two groups (P<0.01); the difference of PSQI scores before and after was -9.15+/-5.68 in the test group and -5.64+/-5.73 in the control group, with a very significant difference before and after treatment in the two groups (P<0.01). CONCLUSION: The therapeutic effect of the needling method for regulating wei and strengthening brain on insomnia is better than that of normal needling method.