Study On The Protective Effect And Mechanism Of Metformin On Reproductive Damage Caused By High-Power Microwave Radiation In Male Rats

Object:It is impossible to disregard the potential health risks of providing convenience to people given the rapid growth of microwave technology.Exploring preventive and therapeutic drugs for microwave radiation damage to reproductive organs is crucial from a social perspective because the reproductive system is one of the vulnerable target systems for microwave radiation damage.Metformin is a commonly prescribed medication for treating type II diabetes mellitus.Research has shown that it is beneficial against oxidative stress and ionizing radiation,but no research has examined its effects on microwave radiation.The purpose of this study was to investigate whether metformin has a protective effect against reproductive damage caused by long-term microwave radiation in male rats,and to explore its mechanism of action from the perspectives of oxidative stress,energy metabolism and apoptosis.Methods:One hundred male Wistar rats were randomly divided into five groups:normal control group(group C),radiation control group(group R),radiation+10 mg/kg metformin group(group R+L),radiation+30 mg/kg metformin group(group R+M),and radiation+90 mg/kg metformin group(group R+H).A microwave radiation source with a frequency of 2.856 GHz and an average power density of 30 m W/cm~2was used for homogeneous whole-body radiation,which lasted 6w,5 d/w and 15 min/d.Group C rats were positioned on the radiation table and inside the radiation container but was not exposed to radiation.The metformin was administered by gavage starting 14 d before the last radiation and was given continuously for 21 d.Groups C and R were given an equal volume of distilled water.Following radiation exposure,serum hormones Testosterone(T)and Inhibin B(INHB),sperm viability,epididymal specific enzymesα-Glucosidase(α-GLU)and Acrosin,light and electron microscopy were used to observe morphological and ultrastructural changes in rat testes;superoxide dismutase(SOD)activity,reduced glutathione(GSH),malondialdehyde(MDA),lactic dehydrogenase(LDH),succinic dehydrogenase(SDH),adenosine triphosphate synthase(ATP synthase),mitochondrial Complex III(Complex III)and mitochondrial Complex IV(Complex IV)contents and changes in heme oxygenase 1(HO-1),B cell lymphoma-2 associated X protein(BAX),B-cell lymphoma-2(BCL-2)and Cleaved-cysteine aspartic acid-specific protease3(Cleaved Caspase-3)protein expression were measured in testes.Results:1.Compared with the group C,the rats showed increased secretion of the serum hormone T and decreased secretion of INHB,decreased sperm motility,decreased epididymalα-GLU and Acrosin content,and damaged testicular tissue structure and ultrastructure after microwave radiation.Compared with the group R,the rats in each drug group showed reduced serum hormone T levels,increased INHB levels,enhanced sperm motility,increased epididymalα-GLU and Acrosin content,and reduced testicular tissue structure and ultrastructural damage.In comparison,the metformin high dose group(90 mg/kg)showed the most protective effect.2.Compared with the group C,the SOD activity and GSH/GSSG ratio of rat testis tissue decreased and MDA content increased after microwave radiation;LDH,SDH,ATP synthase,Complex III and Complex IV content decreased;BCL-2 protein expression level decreased and BAX/BCL-2 ratio and Cleaved Caspase-3 protein expression level increased.Compared with the group R,the SOD activity,GSH/GSSG ratio and MDA content of the testis tissues of the rats in each drug group were increased;LDH,SDH,ATP synthase,Complex III and Complex IV content were increased;BCL-2 protein expression level was increased and BAX/BCL-2 ratio and Cleaved Caspase-3 protein expression level were decreased.Conclusion:1.Rats exposed to high-power microwave radiation showed abnormal serum hormone secretion,decreased sperm vitality,reduced epididymal specific enzyme content,testicular tissue structure and ultrastructure damage,testicular tissue oxidative stress damage,abnormal energy metabolism,and abnormal apoptotic protein expression levels.2.Metformin could alleviates reproductive damage caused by microwave radiation,with the higher dose(90 mg/kg)having a most significant effect.3.The mechanism of metformin against reproductive damage caused by microwave radiation was related to the inhibition of oxidative stress,enhancement of energy metabolism and reduction of tissue apoptosis,and mitochondria could be the target of its protective effect.