Resting State FMRI Study Of Abnormal Insula Functional Connectivity In Patients With T2DM

Objective:Type 2 diabetes mellitus(T2DM)can damage the central nervous system of patients,leading to varying degrees of decline in patients’ multiple cognitive functions.In addition,T2 DM patients are also prone to depression and anxiety and other adverse emotions.Studies have confirmed that the insula is one of the core brain regions of the brain and plays an important role in cognition and emotion.Meanwhile,different subregions of the insula have unique heterogeneity in function.Therefore,this study used the resting state functional connectivity method to observe the functional connectivity of the insula and its different subregions with other brain regions of the whole brain in T2 DM patients,and its relationship with clinical data and cognitive scores,to explore the role of insula and its subregions in brain injury in T2 DM.Methods : A total of 66 patients with T2 DM and 63 healthy controls(HCs)were included.The general clinical data of the subjects were collected,and all the subjects underwent neuropsychological tests and resting-state functional magnetic resonance examination.The bilateral insula and its different subregions were selected as seed points for whole brain functional connectivity analysis,and the functional connectivity of insula and its different subregions and the whole brain between the two groups were compared.The functional connectivity values of brain regions with significant differences between the two groups were extracted.Then,the correlation between the abnormal brain regions’ functional connectivity values and clinical data and neuropsychological evaluation was analyzed.Results:1、Using bilateral insula as seed points,compared to healthy controls,the study found the FC between bilateral insula and bilateral inferior frontal gyrus,right superior temporal gyrus,left angular gyrus,and left cerebellum were significantly decreased in T2 DM patients,and no brain areas with enhanced FC were found.In addition,the strength of FC between bilateral insula and right inferior frontal gyrus in T2 DM patients was negatively correlated with Hb A1c(r=-0.379,P=0.035);2、Using different subregions of bilateral insula as seed points,The results showed that,compared with the HC group,T2 DM patients showed the ventral anterior insula had reduced FC with the right supramarginal gyrus;the dorsal anterior insula had reduced FC with the right inferior frontal gyrus,the right superior temporal gyrus/middle temporal gyrus,the right hippocampus and the right anterior central gyrus;the posterior insula had reduced FC with the right precentral gyrus /postcentral gyrus,but no brain regions with enhanced functional connectivity were found.In addition,Hb A1 c levels were negatively correlated with the strength of FC between bilateral dorsal anterior insula and right hippocampus in T2 DM patients(r=-0.427,P=0.001).Conclusion : This study suggests that insula is involved in the neuropathological process of brain injury in T2 DM and different subregions of insula have different roles in cognitive function affective impairment and sensorimotor abnormality in T2 DM.This study provides a more detailed imaging basis for clarifying the role of insula in the neural mechanism of T2 DM brain injury,and is helpful for the further development of more targeted treatment plans in the clinical treatment of T2 DM related brain injury.