Study On The Formation Conditions Of Lipofuscin And Its Scavenging Effects By Several Natural Anti-oxidants

Lipofuscin,known as age pigment,is an important sign of human aging.Lipofusin cannot be degraded or cleared by exocytosis,which accumulates in lysosomes and cytoplasm of animal longevity cells after mitosis and aging,leading to the deterioration of many age-related chronic diseases such as Alzheimer Mutism,Parkinson's disease,diabetes,etc.Natural antioxidants are ubiquitous in nature,which has the functions of anti-oxidation,delaying aging and promoting body health.However,the scavenging effect of natural antioxidants on lipofuscin is still unknown.This study explored the effects of food ingredients and natural antioxidants on lipofuscin in vitro by constructing an in vitro lipofuscin model,and conducted animal experiments to investigate the effect of natural antioxidants on lipofuscin removal in vivo.By comparing the differences between in vivo and in vitro,screening out natural antioxidants that have a good scavenging capacity on lipofuscin,which has important and practical significance in anti-ageing,preventing senile diseases,and promoting human health.The main work and research results are as follows:?1?Construction of lipofuscin-like model in vitro.Based on the reaction of 1 mg/m L bovine serum albumin?BSA?and 2 mmol/L malondialdehyde?MDA?,the effects of MDA concentration,time,p H and temperature on the formation of lipofuscin-like were investigated,respectively.The results showed that the suitable conditions for the lipofuscin-like model were 1 mg/m L BSA and 2 mmol/L MDA incubating for 72 h at 37?in PBS?0.1 mol/L,p H7.4?.The in vitro lipofuscin-like model constructed under this condition is close to human environment and can be used for the in vitro clearance of lipofuscin by natural antioxidants.?2?The effect of food ingredients on the fluorescence intensity of lipofuscin-like.By reacting different food ingredients?vegetable oils,edible sugar,vitamins,metal ions?with the lipofuscin-like system.In the range of daily taken,the effects of different types and concentrations of food ingredients on lipofuscin were studied using the lipofuscin-like model constructed above.The results showed that vegetable oils,fructose,and vitamin C had inhibitory effects on lipofuscin-like formation,while glucose,vitamin E and metal ions had no significant effects on lipofuscin-like.?3?Scavenging effects of natural antioxidants on lipofuscin-like in vitro.Different natural antioxidants were reacted with lipofuscin-like system,respectively.The semi-inhibitory concentration(IC₅₀ value)was used as an index to study the scavenging effect of natural antioxidants on lipofuscin-like.The results showed that the IC₅₀ values of tannin,resveratrol,rutin,quercetin,anthocyanin,tea polyphenol,lycopene,proanthocyanidin,astaxanthin,glutathione,and lipoic acid were:0.021 mmol/L,0.024 mmol/L,0.033 mmol/L,0.130 mmol/L,0.151 mmol/L,0.157 mmol/L,0.163 mmol/L,0.182 mmol/L,0.220 mmol/L,2.439 mmol/L,25 mmol/L,respectively.Rutin,resveratrol,tea polyphenol and anthocyanin had a strong effect on lipofuscin removal in vitro,so they were selected as raw materials for animal experiments.?4?The effect of natural antioxidants on the removal of lipofuscin in vivo.Animal aging models were constructed by injecting Kunming mice with D-galactose,and the mice were gavaged with antioxidants simultaneously.The superoxide dismutase?SOD?activity,MDA content and lipofuscin content in serum,liver and brain tissues of mice were measured,antioxidants on lipofuscin removal in mice were evaluated based on the changes of various indicators.Animal experiments showed that there were no significant differences between the aging model group and the normal control group?P>0.05?.Compared with the model group,rutin and anthocyanin groups had higher SOD levels in serum and lower MDA and lipofuscin contents in serum,liver and brain,while changes of these indicators in the resveratrol,vitermin E,tea polyphenol,and composite groups were were irregular.The effects of natural antioxidants on lipofuscin removal in vivo needs further study.