Humans ; alpha-Synuclein/genetics* ; Parkinson Disease/pathology*

Humans ; Mitochondria/genetics* ; Mutation/genetics* ; Parkinson Disease/genetics* ; Protein Kinases ; Ubiquitin-Protein Ligases

Humans ; Locomotion ; Mesencephalon ; Midbrain Reticular Formation ; Parkinson Disease

Calcium ; Homeostasis ; Humans ; Parkinson Disease/therapy*

Amino Acid Substitution ; Antineoplastic Agents/pharmacology* ; Cell Line, Tumor ; Drug Resistance, Neoplasm/genetics* ; Gastrointestinal Neoplasms/pathology* ; Humans ; MAP Kinase Signaling System/genetics* ; Mutation, Missense ; Receptor, ErbB-3/metabolism* ; Receptor, Fibroblast Growth Factor, Type 1/metabolism*

Zinc levels are high in pancreatic β-cells, and zinc is involved in the synthesis, processing and secretion of insulin in these cells. However, precisely how cellular zinc homeostasis is regulated in pancreatic β-cells is poorly understood. By screening the expression of 14 Slc39a metal importer family member genes, we found that the zinc transporter Slc39a5 is significantly down-regulated in pancreatic β-cells in diabetic db/db mice, obese ob/ob mice and high-fat diet-fed mice. Moreover, β-cell-specific Slc39a5 knockout mice have impaired insulin secretion. In addition, Slc39a5-deficient pancreatic islets have reduced glucose tolerance accompanied by reduced expression of Pgc-1α and its downstream target gene Glut2. The down-regulation of Glut2 in Slc39a5-deficient islets was rescued using agonists of Sirt1, Pgc-1α and Ppar-γ. At the mechanistic level, we found that Slc39a5-mediated zinc influx induces Glut2 expression via Sirt1-mediated Pgc-1α activation. These findings suggest that Slc39a5 may serve as a possible therapeutic target for diabetes-related conditions.

Parkinson's disease (PD) is the second most common neurodegenerative disease and is typically associated with progressive motor and non-motor dysfunctions. Currently, dopamine replacement therapy is mainly used to relieve the motor symptoms, while its long-term application can lead to various complications and does not cure the disease. Numerous studies have demonstrated that many brain-gut peptides have neuroprotective effects in vivo and in vitro, and may be a promising treatment for PD. In recent years, some progress has been made in studies on the neuroprotective effects of some newly-discovered brain-gut peptides, such as glucagon-like peptide 1, pituitary adenylate cyclase activating polypeptide, nesfatin-1, and ghrelin. However, there is still no systematic review on the neuroprotective effects common to these peptides. Thus, here we review the neuroprotective effects and the associated mechanisms of these four peptides, as well as other brain-gut peptides related to PD, in the hope of providing new ideas for the treatment of PD and related clinical research.

Animals ; Behavior, Animal ; physiology ; Dopamine ; metabolism ; Dopaminergic Neurons ; physiology ; Humans ; Mice ; Motor Activity ; physiology ; Parkinson Disease ; metabolism ; physiopathology ; Pars Compacta ; physiopathology

Animals ; Dopamine ; metabolism ; Dopaminergic Neurons ; metabolism ; Humans ; Iron ; metabolism ; Oxidative Stress ; Parkinson Disease ; metabolism ; Pars Compacta ; metabolism ; alpha-Synuclein ; metabolism