Alterations in adult hippocampal neurogenesis, aberrant protein s-nitrosylation, and associated spatial memory loss in streptozotocin-induced diabetes mellitus type 2 mice

Document Type : Original Article


Neurobiology Research Laboratory, Department of Healthcare Biotechnology, Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad, Pakistan


Objective(s): Epidemiological and biochemical studies conducted over the past two decades have established a strong link between type 2 diabetes mellitus (T2DM) and Alzheimer’s disease (AD). However, the exact mechanisms through which aberrations in insulin signaling associated with T2DM contribute to cognitive decline are not yet known.
Materials and Methods: In an effort to explore possible molecular links between T2DM and AD, the present study investigated the status of neurodegeneration, adult hippocampal neurogenesis, and nitrosative stress induced protein S-nitrosylation in streptozotocin (STZ) induced mice models of T2DM. Morris water maze task and subsequent histological and immunohistochemical assessment were conducted. Expression of neurogenesis markers (Ki67, DCX, and NeuN) and APP 770 was determined by qRT-PCR.
Results: A significant decline in spatial learning and reference memory was observed with consequent neurodegeneration in brain cortex and hippocampus in the diabetic group as compared to the control group. A subsequent increase in expression of APP 770 was also observed in T2DM brain regions. Moreover, a significant decrease in transcriptional expression of Ki67, DCX, and NeuN was also evident in T2DM brain regions, which indicated possible aberrations in adult hippocampal neurogenesis in T2DM. Furthermore, an increased immunohistochemical signal for S-nitrosylation was also observed in T2DM, which also suggested its potential contribution in T2DM associated neuronal deterioration.
Conclusion: It is suggested that these identified aberrations in the diabetic brain may communally increase the susceptibility of developing AD in patients with T2DM. Further studies of the underlying molecular mechanisms may help to strategize a combination therapy for these debilitating disorders.


1.  Smith L. Global report on Diabetes. United States: World health organization;2016.
2. Rossetti L, Giaccari A, DeFronzo RA. Glucose toxicity. Diabetes Care 1990; 13:610-630.
3. Scheen AJ. Pathophysiology of type 2 diabetes. Acta Clin Belg 2014; 58:335-341.
4. Verdile G, Fuller SJ, Martins RN. The role of type 2 diabetes in neurodegeneration. Neurobiol Dis 2015; 84:22-38.
5. De la Monte SM, Wands JR. Alzheimer's disease is type 3 diabetes-evidence reviewed. J Diabetes Sci Technol 2008; 2:1101-1113.
6. Geroldi C, Frisoni GB, Paolisso G, Bandinelli S, Lamponi M, Abbatecola AM, et al. Insulin resistance in cognitive impairment: the InCHIANTI study. Arch Neurol 2005; 62:1067-1072.
7. Biessels GJ, Kamal A, Urban IJ, Spruijt BM, Erkelens DW, Gispen WH. Water maze learning and hippocampal synaptic plasticity in streptozotocin-diabetic rats: effects of insulin treatment. Brain Res 1998; 800:125-135.
8. Kerti L, Witte AV, Winkler A, Grittner U, Rujescu D, Flöel. A Higher glucose levels associated with lower memory and reduced hippocampal microstructure. Neurology 2013; 81:1746-1752.
9. van Bussel FC, Backes WH, Hofman PA, van Oostenbrugge RJ, Kessels AG, van Boxtel MP, et al. On the interplay of microvasculature, parenchyma, and memory in type 2 diabetes. Diabetes Care 2015; 38:876-882.
10. Valente T, Gella A, Fernàndez-Busquets X, Unzeta M, Durany N. Immunohistochemical analysis of human brain suggests pathological synergism of Alzheimer's disease and diabetes mellitus. Neurobiol Dis 2010; 37:67-76.
11. Takeda S, Sato N, Uchio-Yamada K, Sawada K, Kunieda T, Takeuchi D, et al. Diabetes-accelerated memory dysfunction via cerebrovascular inflammation and Aβ deposition in an Alzheimer mouse model with diabetes. Proc Natl Acad Sci U S A 2010; 107:7036-7041.
12. Ramos-Rodriguez JJ, Molina-Gil S, Ortiz-Barajas O, Jimenez-Palomares M, Perdomo G, Cozar-Castellano I, et al. Central proliferation and neurogenesis is impaired in type 2 diabetes and prediabetes animal models. PloS One 2014; 9:89229.
13. Haughey NJ, Nath A, Chan SL, Borchard AC, Rao MS, Mattson MP. Disruption of neurogenesis by amyloid beta-peptide, and perturbed neural progenitor cell homeostasis, in models of Alzheimer's disease. J Neurochem 2002; 83:1509-1524.
14. Foster MW, Liu L, Zeng M, Hess DT, Stamler JS. A genetic analysis of nitrosative stress. Biochemistry 2009; 48:792-799.
15. Nakamura T, Lipton SA. Redox regulation of mitochondrial fission, protein misfolding, synaptic damage, and neuronal cell death: potential implications for Alzheimer’s and Parkinson’s diseases. Apoptosis 2010; 15:1354-1363.
16. Dong J, Xu H, Wang PF, Cai GJ, Song HF, Wang CC, et al. Nesfatin-1 stimulates fatty-acid oxidation by activating AMP-activated protein kinase in STZ-induced type 2 diabetic mice. PloS One 2013; 8:83397.
17. Gage GJ, Kipke DR, Shain W. Whole animal perfusion fixation for rodents. J Vis Exp 2012; 30:3564.
18. Livak KJ, Schmittgen TD. Analysis of relative gene expression data using real-time quantitative PCR and the 2− ΔΔCT method. Methods 2001; 25:402-408.
19. Manschot SM, Biessels GJ, Cameron NE, Cotter MA, Kamal A, Kappelle LJ, et al. Angiotensin converting enzyme inhibition partially prevents deficits in water maze performance, hippocampal synaptic plasticity and cerebral blood flow in streptozotocin-diabetic rats. Brain Res 2003; 966:274-282.
20. Zheng H, Zheng Y, Zhao L, Chen M, Bai G, Hu Y, et al. Cognitive decline in type 2 diabetic db/db mice may be associated with brain region-specific etabolic disorders. Biochim Biophys Acta 2017; 1863:266-273.
21. Ohara T, Doi Y, Ninomiya T, Hirakawa Y, Hata J, Iwaki T, et al. Glucose tolerance status and risk of dementia in the community. The Hisayama Study. Neurology 2011; 77:1126–1134.
22. Biessels GJ, Staekenborg S, Brunner E, Brayne C, Scheltens P. Risk of dementia in diabetes mellitus: a systematic review. Lancet Neurol 2006; 5:64–74.
23. Kawamura T, Umemura T, Hotta N. Cognitive impairment in diabetic patients:Can diabetic control prevent cognitive decline? J Diabetes Investig 2012; 3:413-423.
24. Umegaki H. Neurodegeneration in diabetes mellitus. Adv Exp Med Biol 2012; 724:258-265.
25. Moran C, Beare R, Phan TG, Bruce DG, Callisaya ML, Srikanth V. Alzheimer's disease neuroimaging initiative (ADNI). Type 2 diabetes mellitus and biomarkers of neurodegeneration. Neurology 2015; 85:1123-1130.
26. Pham E, Crews L, Ubhi K, Hansen L, Adame A, Cartier A, et al. Progressive accumulation of amyloid-beta oligomers in Alzheimer's disease and in amyloid precursor protein transgenic mice is accompanied by selective alterations in synaptic scaffold proteins. FEBS J 2010; 277:3051-3067.
27. Noriega-Cisneros R, Cortés-Rojo C, Manzo-Avalos S, Clemente-Guerrero M, Calderón-Cortés E, Salgado-Garciglia R, et al. Mitochondrial response to oxidative and nitrosative stress in early stages of diabetes. Mitochondrion 2013; 13:835-840.
28. Wadham C, Parker A, Wang L, Xia P. High glucose attenuates protein S-nitrosylation in endothelial cells: role of oxidative stress. Diabetes 2007; 56:2715-2721.
29. Akhtar MW, Sanz-Blasco S, Dolatabadi N, Parker J, Chon K, Lee MS, et al. Elevated glucose and oligomeric β-amyloid disrupt synapses via a common pathway of aberrant protein S-nitrosylation. Nat Commun 2016; 7:102-142.
30. Lang BT, Yan Y, Dempsey RJ, Vemuganti R. Impaired neurogenesis in adult type-2 diabetic rats. Brain Res 2009; 1258:25-33.
31. Zhang WJ, Tan YF, Yue JT, Vranic M, Wojtowicz JM. Impairment of hippocampal neurogenesis in streptozotocin-treated diabetic rats. Acta Neurol Scand 2008; 117:205-210.
32. Nam SM, Kim JW, Yoo DY, Jung HY, Choi JH, Hwang IK, et al. Reduction of adult hippocampal neurogenesis is amplified by aluminum exposure in a model of type 2 diabetes. J Vet Sci 2016; 17:13-20.
33. Ahmed S, Mahmood Z, Javed A, Hashmi SN, Zerr I, Zafar S, et al. Effect of metformin on adult hippocampal neurogenesis: Comparison with donepezil and links to cognition. J Mol Neurosci 2017; 62:88-98.
34. Plummer S, Van den Heuvel C, Thornton E, Corrigan F, Cappai R. The neuroprotective properties of the amyloid precursor protein following traumatic brain injury. Aging Dis 2016; 7:163-179.
35. Zhou ZD, Chan CH, Ma QH, Xu XH, Xiao ZC, Tan EK. The roles of amyloid precursor protein (APP) in neurogenesis: Implications for pathogenesis and therapy of Alzheimer disease. Cell Adh Migr 2011; 5:280-292.