This study was undertaken to further characterize the secretory response of the rat pancreas after reserpine treatment. Rats were given reserpine (1 mg kg-1 day-1 i.p.) or vehicle for 7 days. To distinguish between specific effects of reserpine and those related to secondary malnutrition caused by the drug, the secretory response of a group of pair-fed (PF) animals to reserpine was also investigated. Amylase release from dispersed pancreatic acini, prepared from control (C), PF and reserpine-treated (R) rats were used to evaluate functional secretory capacity. Reserpine and pair-feeding caused reduced responses of pancreatic acini to secretin. The pair-feeding-altered secretin response was greatly improved by increasing extracellular Ca2+ concentration, whereas a slight improvement was noticed in the R group. Reserpine significantly reduced the secretory response to the ionophore A23187 at concentrations above 5 x 10(-7) M in 1.25 mM Ca2+; in 2.5 mM Ca2+, the response to the ionophore was significantly higher in the R group than in C at all ionophore concentrations. Furthermore, at 2 x 10(-7) M ionophore, the secretory response to secretin in the R group became significantly higher than that in the C group but comparable to that of the control+ionophore. In conclusion, reserpine affects the secretory response to secretin as did pre-exposure of pancreatic acini to a high concentration of carbamylcholine. The modified secretory response to the ionophore following reserpine treatment indicates that reserpine may act as a 'Ca2+ entry mechanism' antagonist which may explain the partial reduction in the secretin response.
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http://dx.doi.org/10.1159/000201129 | DOI Listing |
J Liposome Res
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School of Pharmacy and Food Engineering, Wuyi University, Jiangmen, Guangdong, China.
This study aimed to design a novel liposome containing GA modified phosphatidylcholine lipid (GA-PC Lip) and determine its susceptibility to tumor over-expressed secretory phospholipase A (sPLA) and its anti-cancer effect compared to conventional liposomes (Convention Lip). The liposomes were characterized for size, drug loading, encapsulation efficiency, and stability. A 6-CF release assay was conducted to assess the sensitivity of the liposomes to the tumor-overexpressed secretory phospholipase A (sPLA).
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New Cornerstone Science Laboratory, State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, National Biomedical Imaging Center, The Beijing Laboratory of Biomedical Imaging, Peking-Tsinghua Center for Life Sciences, School of Future Technology, Peking University, Beijing 100871, China.
Glucose-stimulated insulin release from pancreatic β-cells is critical for maintaining blood glucose homeostasis. An abrupt increase in blood glucose concentration evokes a rapid and transient rise in insulin secretion followed by a prolonged, slower phase. A diminished first phase is one of the earliest indicators of β-cell dysfunction in individuals predisposed to develop type 2 diabetes.
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August 2024
Institute of Pediatrics, Children's Hospital of Fudan University, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism, Ministry of Science and Technology, Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China.
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Key Laboratory of Metabolism and Molecular Medicine of the Ministry of Education, Department of Biochemistry and Molecular Biology of School of Basic Medical Sciences and Department of Endocrinology and Metabolism of Zhongshan Hospital, Fudan University, Shanghai 200032, China.
In addition to their pivotal roles in energy storage and expenditure, adipose tissues play a crucial part in the secretion of bioactive molecules, including peptides, lipids, metabolites, and extracellular vesicles, in response to physiological stimulation and metabolic stress. These secretory factors, through autocrine and paracrine mechanisms, regulate various processes within adipose tissues. These processes include adipogenesis, glucose and lipid metabolism, inflammation, and adaptive thermogenesis, all of which are essential for the maintenance of the balance and functionality of the adipose tissue micro-environment.
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Department of Neurosurgery West China Hospital, Sichuan University, Chengdu, China.
Resveratrol, a polyphenolic compound known for its diverse biological activities, has demonstrated multiple pharmacological effects, including anti-inflammatory, anti-aging, anti-diabetic, anti-cancer, and cardiovascular protective properties. Recent studies suggest that these effects are partly mediated through the regulation of macrophage polarization, wherein macrophages differentiate into pro-inflammatory M1 or anti-inflammatory M2 phenotypes. Our review highlights how resveratrol modulates macrophage polarization through various signaling pathways to achieve therapeutic effects.
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