Pengzi Zhang

Diabetic foot is a severe public health issue, yet rare studies investigated its global epidemiology. Here we performed a systematic review and meta-analysis through searching PubMed, EMBASE, ISI Web of science, and Cochrane database. We found that that global diabetic foot ulcer prevalence was 6.3% (95%CI: 5.4-7.3%), which was higher in males (4.5%, 95%CI: 3.7-5.2%) than in females (3.5%, 95%CI: 2.8-4.2%), and higher in type 2 diabetic patients (6.4%, 95%CI: 4.6-8.1%) than in type 1 diabetics (5.5%, 95%CI: 3.2-7.7%). North America had the highest prevalence (13.0%, 95%CI: 10.0-15.9%), Oceania had the lowest (3.0%, 95% CI: 0.9-5.0%), and the prevalence in Asia, Europe, and Africa were 5.5% (95%CI: 4.6-6.4%), 5.1% (95%CI: 4.1-6.0%), and 7.2% (95%CI: 5.1-9.3%), respectively. Australia has the lowest (1.5%, 95%CI: 0.7-2.4%) and Belgium has the highest prevalence (16.6%, 95%CI: 10.7-22.4%), followed by Canada (14.8%, 95%CI: 9.4-20.1%) and USA (13.0%, 95%CI: 8.3-17.7%). The patients with diabetic foot ulcer were older, had a lower body mass index, longer diabetic duration, and had more hypertension, diabetic retinopathy, and smoking history than patients without diabetic foot ulceration. Our results provide suggestions for policy makers in deciding preventing strategy of diabetic foot ulceration in the future. Key messages Global prevalence of diabetic foot is 6.3% (95%CI: 5.4-7.3%), and the prevalence in North America, Asia, Europe, Africa and Oceania was 13.0% (95%CI: 10.0-15.9%), 5.5% (95%CI: 4.6-6.4%), 5.1% (95%CI: 4.1-6.0%), 7.2% (95%CI: 5.1-9.3%), and 3.0% (95% CI: 0.9-5.0%). Diabetic foot was more prevalent in males than in females, and more prevalent in type 2 diabetic foot patients than in type 1 diabetic foot patients. The patients with diabetic foot were older, had a lower body mass index, longer diabetic duration, and had more hypertension, diabetic retinopathy, and smoking history than patients without diabetic foot.

Abstract Pathogenic factors driving obesity to type 2 diabetes (T2D) are not fully understood. Group 1 innate lymphoid cells (ILC1s) are effectors of innate immunity and enriched in inflamed tissues. Here we show that the number of adipose ILC1s increases in obese T2D patients and correlates with glycemic parameters and with the number of ILC1s in the blood; circulating ILC1 numbers decrease as a result of metabolic improvements after bariatric surgery. In vitro co-culture experiments show that human adipose ILC1s promote adipose fibrogenesis and CD11c + macrophage activation. Reconstruction of the adipose ILC1 population in Prkdc −/− IL2rg −/− mice by adoptive transfer drives adipose fibrogenesis through activation of TGFβ1 signaling; however, transfer of Ifng −/− ILC1s has no effect on adipose fibrogenesis. Furthermore, inhibiting adipose accumulation of ILC1s using IL-12 neutralizing antibodies attenuates adipose tissue fibrosis and improves glycemic tolerance. Our data present insights into the mechanisms of local immune disturbances in obesity-related T2D.

Erythropoietin (EPO) has beneficial effects on glucose metabolism and insulin resistance. However, the mechanism underlying these effects has not yet been elucidated. This study aimed to investigate how EPO affects hepatic glucose metabolism. Here, we report that EPO administration promoted phosphatidylinositol 3-kinase (PI3K)/AKT pathway activation in palmitic acid (PA)-treated HepG2 cells and in the liver of high-fat diet (HFD)-fed mice, whereas adenovirus-mediated silencing of the erythropoietin receptor (EPOR) blocked EPO-induced AKT signalling in HepG2 cells. Importantly, a peroxisome proliferator-activated receptor γ (PPARγ) antagonist and PPARγ small interfering RNA (siRNA) abrogated the EPO-induced increase in p-AKT in HepG2 cells. Lentiviral vector-mediated hepatic PPARγ silencing in HFD-fed C57BL/6 mice impaired EPO-mediated increases in glucose tolerance, insulin sensitivity and hepatic AKT activation. Furthermore, EPO activated the AMP-activated protein kinase (AMPK)/sirtuin 1 (SIRT1) signalling pathway, and AMPKα and SIRT1 knockdown each attenuated the EPO-induced PPARγ expression and deacetylation and PPARγ-dependent AKT activation in HepG2 cells. In summary, these findings suggest that PPARγ is involved in EPO/EPOR-induced AKT activation, and targeting the PPARγ/AKT pathway via EPO may have therapeutic implications for hepatic insulin resistance and type 2 diabetes.