Objective To investigate anxiety-and depression-like behaviors in Cynomolgus monkeys with type 2 diabetes mellitus(T2DM),and to explore their correlations with biochemical parameters.Methods Cynomolgus monkeys were divided into a T2DM group(fasting plasma glucose(FPG)≥ 5.6 mmol/L)and control group(FPG＜4.2 mmol/L)(n=3 per group).Age,sex,body mass,body mass index(BMI),FPG,blood lipids,atherosclerosis index(AI),and tumor necrosis factor-α(TNF-α)levels were measured in both groups.Anxiety-like behaviors were assessed using the human intrude test(HIT)and depression-like behaviors were evaluated using the apathy feeding test(AFT).Relationships between behavioral parameters and biochemical/inflammatory markers were evaluated using Pearson's correlation analysis.Results(1)FPG,AI,and TNF-αlevels were significantly elevated while high-density lipoprotein cholesterol levels were reduced in the T2DM group compared with the control group(P＜0.05).(2)Regarding the HIT result,the durations of anxious(stare phase)and back-of-cage(stare phase)behaviors were higher in the T2DM group than in the control group(P＜0.05),while the durations of locomotor behaviors(baseline phase,profile phase,back phase)were significantly shorter(P＜0.05).(3)The AFT revealed that food retrieval latency was significantly delayed in the T2DM group(P＜0.05).Pearson's analysis identified a positive correlation between back-of-cage(stare phase)duration and AI(r=0.828,P=0.042),while locomotion during the back phase showed a negative corr-elation with AI(r=-0.842,P=0.035).Conclusions Cynomolgus monkeys with T2DM display distinct anxiety-and depression-like behavioral phenotypes,with a significant association between the AI and anxiety-related behaviors.These findings provide novel insights into the pathophysiological mechanisms linking T2DM with neuropsychiatric comorbidities.

Objective To investigate anxiety-and depression-like behaviors in Cynomolgus monkeys with type 2 diabetes mellitus(T2DM),and to explore their correlations with biochemical parameters.Methods Cynomolgus monkeys were divided into a T2DM group(fasting plasma glucose(FPG)≥ 5.6 mmol/L)and control group(FPG＜4.2 mmol/L)(n=3 per group).Age,sex,body mass,body mass index(BMI),FPG,blood lipids,atherosclerosis index(AI),and tumor necrosis factor-α(TNF-α)levels were measured in both groups.Anxiety-like behaviors were assessed using the human intrude test(HIT)and depression-like behaviors were evaluated using the apathy feeding test(AFT).Relationships between behavioral parameters and biochemical/inflammatory markers were evaluated using Pearson's correlation analysis.Results(1)FPG,AI,and TNF-αlevels were significantly elevated while high-density lipoprotein cholesterol levels were reduced in the T2DM group compared with the control group(P＜0.05).(2)Regarding the HIT result,the durations of anxious(stare phase)and back-of-cage(stare phase)behaviors were higher in the T2DM group than in the control group(P＜0.05),while the durations of locomotor behaviors(baseline phase,profile phase,back phase)were significantly shorter(P＜0.05).(3)The AFT revealed that food retrieval latency was significantly delayed in the T2DM group(P＜0.05).Pearson's analysis identified a positive correlation between back-of-cage(stare phase)duration and AI(r=0.828,P=0.042),while locomotion during the back phase showed a negative corr-elation with AI(r=-0.842,P=0.035).Conclusions Cynomolgus monkeys with T2DM display distinct anxiety-and depression-like behavioral phenotypes,with a significant association between the AI and anxiety-related behaviors.These findings provide novel insights into the pathophysiological mechanisms linking T2DM with neuropsychiatric comorbidities.