Abstract
Background: NGF deficiency is one of the reasons for reduced β-cells survival in diabetes. Our previous experiments revealed the ability of low-weight NGF mimetic, GK-2, to reduce hyperglycaemia in a model of advanced diabetes. The increase in DNA damage in advanced diabetes was repeatedly reported, while there were no data about DNA damage in the initial diabetes.
Aim: The study aimed to establish whether DNA damage occurs in initial diabetes and whether GK-2 is able to overcome the damage.
Methods: The early-stage diabetes was modelled in Balb/c mice by streptozotocin (STZ) (130 mg/kg, i.p.). GK-2 was administered at a dose of 0.5 mg/kg, i.p., subchronically. The evaluation of DNA damage was performed using the alkaline comet assay; the percentage of DNA in the tail (%TDNA) and the percentage of the atypical DNA comets (“ghost cells”) were determined.
Results: STZ at this subthreshold dose produced a slight increase in glycemia and MDA. Meanwhile, pronounced DNA damage was observed, concerning mostly the percentage of “ghost cells” in the pancreas, the liver and kidneys. GK-2 attenuated the degree of hyperglycaemia and reduced the % of “ghost cells” and %TDNA in all the organs examined; this effect continued after discontinuation of the therapy.
Conclusion: Early-stage diabetes is accompanied by DNA damage, manifested by the increase of “ghost cells” percentage. The severity of these changes significantly exceeds the degree of hyperglycaemia and MDA accumulation. GK-2 exerts an antihyperglycaemic effect and attenuates the degree of DNA damage. Our results indicate that the comet assay is a highly informative method for search of antidiabetic medicines.
Keywords: DNA comet, “ghost cells”, early-stage diabetes, GK-2, NGF, PI3K/Akt, STZ.
Graphical Abstract
[http://dx.doi.org/10.1126/science.3306916] [PMID: 3306916]
[http://dx.doi.org/10.1007/BF02532343] [PMID: 8895847]
[http://dx.doi.org/10.1080/15438600490455079] [PMID: 15203882]
[http://dx.doi.org/10.1007/s001250100650] [PMID: 11692177]
[http://dx.doi.org/10.1097/MPA.0000000000000243] [PMID: 25401376]
[PMID: 21701997]
[http://dx.doi.org/10.1111/j.1600-0404.1990.tb00984.x] [PMID: 2375241]
[http://dx.doi.org/10.1080/08977190310001629566] [PMID: 14708938]
[http://dx.doi.org/10.2174/1381612824666181008105641] [PMID: 30295186]
[http://dx.doi.org/10.4236/nm.2014.52013]
[http://dx.doi.org/10.1186/s12929-015-0198-z] [PMID: 26642930]
[http://dx.doi.org/10.1073/pnas.90.12.5781] [PMID: 8516328]
[http://dx.doi.org/10.5114/aoms.2015.56342] [PMID: 26788077]
[http://dx.doi.org/10.1210/10.1210/er.2006-0038] [PMID: 17353295]
[http://dx.doi.org/10.2337/diabetes.52.1.102] [PMID: 12502499]
[http://dx.doi.org/10.1016/j.bbagen.2014.05.017] [PMID: 24905298]
[http://dx.doi.org/10.1016/j.mrgentox.2011.10.004] [PMID: 22015262]
[http://dx.doi.org/10.1016/j.mrfmmm.2012.01.004] [PMID: 22285873]
[http://dx.doi.org/10.1016/j.mrfmmm.2014.11.009] [PMID: 26255943]
[http://dx.doi.org/10.3906/biy-1507-55]
[http://dx.doi.org/10.1016/j.mrgentox.2017.11.002] [PMID: 29307371]
[http://dx.doi.org/10.1016/S0891-5849(98)00053-7] [PMID: 9680185]
[http://dx.doi.org/10.1080/10715762.2017.1315114] [PMID: 28372523]
[http://dx.doi.org/10.1111/cei.12020] [PMID: 23379439]
[http://dx.doi.org/10.1248/bpb.29.1110] [PMID: 16755002]
[PMID: 21225225]
[http://dx.doi.org/10.1002/pds.4337] [PMID: 29108130]
[http://dx.doi.org/10.3109/10715769809065821] [PMID: 9736317]
[http://dx.doi.org/10.1016/j.mrgentox.2011.05.010] [PMID: 21645630]
[PMID: 30183153]
[PMID: 25221569]
[http://dx.doi.org/10.32607/20758251-2017-9-2-94-102] [PMID: 28740732]
[http://dx.doi.org/10.1155/2014/819065] [PMID: 24977161]
[http://dx.doi.org/10.1007/s10517-015-3068-5] [PMID: 26519266]
[http://dx.doi.org/10.1007/s10517-016-3414-2] [PMID: 27502535]
[http://dx.doi.org/10.1155/2012/120645] [PMID: 22844268]
[http://dx.doi.org/10.1038/s41419-017-0135-z] [PMID: 29371661]
[http://dx.doi.org/10.1016/j.ejps.2011.07.012]
[http://dx.doi.org/10.1134/S1607672914030028] [PMID: 24993963]
[http://dx.doi.org/10.1002/jcb.20549] [PMID: 16088938]
[http://dx.doi.org/10.1038/sj.emboj.7601111] [PMID: 16642037]
[http://dx.doi.org/10.1152/ajpendo.00031.2004] [PMID: 15271644]
[http://dx.doi.org/10.1007/s10517-018-4069-y] [PMID: 29658083]
[http://dx.doi.org/10.1016/S0959-4388(00)00092-1] [PMID: 10851172]