Background Previous studies on telemedicine interventions have shown that older diabetic patients experience difficulty in using computers, which is a barrier to remote communication between medical teams and older diabetic patients. However, older people in China tend to find it easy to use mobile phones and personal messaging apps that have a user-friendly interface. Therefore, we designed a mobile health (mHealth) system for older people with diabetes that is based on mobile phones, has a streamlined operation interface, and incorporates maximum automation. Objective The goal of the research was to investigate the use of mobile phone–based telemedicine apps for management of older Chinese patients with type 2 diabetes mellitus (T2DM). Variables of interest included efficacy and safety. Methods A total of 91 older (aged over 65 years) patients with T2DM who presented to our department were randomly assigned to one of two groups. Patients in the intervention group (n=44) were provided glucometers capable of data transmission and received advice pertaining to medication, diet, and exercise via the mHealth telemedicine system. Patients assigned to the control group (n=47) received routine outpatient care with no additional intervention. Patients in both groups were followed up at regular 3-month intervals. Results After 3 months, patients in the intervention group showed significant ( P <.05) improvement in postprandial plasma glucose level. After 6 months, patients in the intervention group exhibited a decreasing trend in postprandial plasma glucose and glycated hemoglobin levels compared with the baseline and those in the control group ( P <.05). Conclusions Mobile phone–based telemedicine apps help improve glycemic control in older Chinese patients with T2DM. Trial Registration China Clinical Trial Registration Center ChiCTR 1800015214; http://www.chictr.org.cn/showprojen.aspx?proj=25949 (Archived by WebCite at http://www.webcitation.org/73wKj1GMq).

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ObjectiveCaveolin-3 (CAV3) protein is known to be expressed specifically in various myocytes, but its physiological function remains unclear. CAV3, located at the cell membrane, may promote the sensitivity of the Akt signaling pathway, which is closely related to glucose metabolism and to cell growth and proliferation.MethodsThe CAV3 gene was stably transfected into C2C12 muscle cells, and the effects were evaluated by biochemical assays, WB and confocal microscopy for the observation of cellular glucose metabolism, growth and proliferation, and the effect of CAV3 on the Akt signaling pathway with no insulin stimulation.ResultsAfter C2C12 cells were transfected with the mouse CAV3 gene, which increased CAV3 expression, the abundance of the CAV3 and GLUT4 proteins on the cell membrane increased, but the total GLUT4 protein content of the cell was unchanged. Glucose uptake was increased, and this did not affect the glycogen synthesis, but the cell surface area and cell proliferation increased. While there were significant increases in p-Akt and p-p70s6K, which is a downstream component of Akt signaling, the level of GSK3β protein, another component of Akt signaling did not change.ConclusionsThe muscle, CAV3 protein can activate Akt signaling, increase GLUT4 protein localization in the cell membrane, increase glucose uptake, and promote myocyte growth and proliferation. CAV3 protein has a physiological role in glycometabolism, growth and proliferation, independent of insulin stimulation.

Caveolin-3 (CAV3) is a muscle-specific protein present within the muscle cell membrane that affects signaling pathways, including the insulin signaling pathway. A previous assessment of patients with newly developed type 2 diabetes (T2DM) demonstrated that CAV3 gene mutations may lead to changes in protein secondary structure. A severe CAV3 P104L mutation has previously been indicated to influence the phosphorylation of skeletal muscle cells and result in impaired glucose metabolism. In the present study, the effect of CAV3 K15N gene transfection in C2C12 cells was assessed. Transfection with K15N reduced the expression of total CAV3 and AKT2 proteins in the cells, and the translocation of glucose transporter type 4 to the muscle cell membrane, which resulted in decreased glucose uptake and glycogen synthesis in myocytes. In conclusion, these results indicate that the CAV3 K15N mutation may cause insulin-stimulated impaired glucose metabolism in myocytes, which may contribute to the development of T2DM.

The caveolin‐3 (CAV3) protein is known to be specifically expressed in various myocytes, and skeletal muscle consumes most of the blood glucose as an energy source to maintain normal cell metabolism and function. The P104L mutation in the coding sequence of the human CAV3 gene leads to autosomal dominant disease limb‐girdle muscular dystrophy type 1C (LGMD‐1C). We previously reported that C2C12 cells transiently transfected with the P104L CAV3 mutant exhibited decreased glucose uptake and glycogen synthesis after insulin stimulation. The present study aimed to examine whether the P104L mutation affects C2C12 cell glucose metabolism, growth, and proliferation without insulin stimulation. C2C12 cells stably transfected with CAV3‐P104L were established, and biochemical assays, western blot analysis and confocal microscopy were used to observe glucose metabolism as well as cell growth and proliferation and to determine the effect of the P104L mutation on the PI3K/Akt signaling pathway. Without insulin stimulation, C2C12 cells stably transfected with the P104L CAV3 mutant exhibited decreased glucose uptake and glycogen synthesis, decreased CAV3 expression and reduced localization of CAV3 and GLUT4 on the cell membrane. The P104L mutant significantly reduced the cell diameters, but accelerated cell proliferation. Akt phosphorylation was inhibited, and protein expression of GLUT4, p‐GSK3β, and p‐p70s6K, which are molecules downstream of Akt, was significantly decreased. The CAV3‐P104L mutation inhibits glycometabolism and cell growth but accelerates C2C12 cell proliferation by reducing CAV3 protein expression and cell membrane localization, which may contribute to the pathogenesis of LGMD‐1C.