Activating Transcription Factor 6/metabolism; Endoplasmic Reticulum/metabolism; Glucosamine/metabolism; Glucose Transporter Type 4/metabolism; Muscle Fibers, Skeletal/metabolism; Activating Transcription Factor 6/genetics; Analysis of Variance; Animals; Blotting, Western; Cell Line; Cells, Cultured; Chromatin Immunoprecipitation; Dose-Response Relationship, Drug; Endoplasmic Reticulum/drug effects; Endoplasmic Reticulum Chaperone BiP; Glucosamine/pharmacology; Glucose/metabolism; Glucose/pharmacology; Glucose Transporter Type 4/genetics; Heat-Shock Proteins/genetics; Heat-Shock Proteins/metabolism; Humans; Insulin/metabolism; Insulin/pharmacology; Insulin Resistance/physiology; MADS Domain Proteins/genetics; MADS Domain Proteins/metabolism; MEF2 Transcription Factors; Middle Aged; Molecular Chaperones/genetics; Molecular Chaperones/metabolism; Muscle Fibers, Skeletal/cytology; Muscle Fibers, Skeletal/drug effects; Myogenic Regulatory Factors/genetics; Myogenic Regulatory Factors/metabolism; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; RNA, Messenger/genetics; RNA, Messenger/metabolism; RNA, Small Interfering/genetics; RNA, Small Interfering/metabolism; RNA-Binding Proteins/genetics; RNA-Binding Proteins/metabolism; Rats; Reverse Transcriptase Polymerase Chain Reaction; Transcription Factors/genetics; Transcription Factors/metabolism