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Objective To observe the serum vascular endothelial growth factor (VEGF),apelin and heme oxygenase-1 (HO-1) levels in patients with type 2 diabetes mellitus (T2DM) and to explore their their relationship with diabetic retinopathy (DR).Methods A total of 208 patients with T2DM and 50 healthy subjects (control group) from the Central Hospital of Western Hainan during January 2014 and December 2017 were selected in this study.Vision,slit lamp microscope,indirect ophthalmoscope and FFA examinations were performed on all the subjects.According to the results of the examinations combined with the DR clinical staging criteria,the patients were divided into non-DR (NDR) group,non-proliferative DR (NPDR) group,and proliferative DR (PDR) group,with 72,76 and 60 patients in each,respectively.The clinical data of each group were recorded,and the levels of fasting blood glucose (FPG),HbA1c,total cholesterol (TC),three acylglycerol (TG),high density lipoprotein (HDL-C),low density lipoprotein (LDL-C),VEGF,apelin and HO-1 were detected in each group.The receiver operating characteristic curve (ROC) were used to analyze the value of VEGF,apelin and HO-1 in predicting the occurrence of PDR.Correlation analysis of serum VEGF,Apelin and HO-1 with clinical parameters in PDR patients by Pearson correlation analysis.Results The level of VEGF (56.82± 10.16 vs 91.74±22.83,140.15±36.40,195.28±42.26 pg/ml)and apelin (2.95±0.53 vs 4.68±0.74,7.25±1.13,10.16± 1.35 ng/ml) in PDR group were significantly higher than those in NPDR,NDR and control groups (F=17.306,21.814;P<0.05).The level of HO-1 (50.37±10.14 vs 43.58±8.16,30.25t6.28,22.60±4.72 mmol/L) in PDR group was significantly lower than those in NPDR,NDR and control groups (F=15.827,P<0.05).The ROC curve analysis showed that the best cut-offvalues of serum VEGF,apelin and HO-1 were 162.50 pg/ml,8.30 ng/ml,27.13 mmol/L,and the three combined to predict PDR of AUC (95%CI)was 0.906 (0.849-0.962),and their sensitivity (90.3%) and specificity (83%) were better.The correlation analysis showed that the VEGF,apelin and HO-1 of PDR patients were correlated with the course of diabetes (r=0.382,0.416,-0.36;P<0.05),FPG (r=0.438,0.460,-0.397;P<0.05) and HbAlc (r=0.375,0.478,-0.405;P<0.05),and the serum VEGF were correlated with apelin and HO-1 (r=0.793,-0.594;P<0.01).Conclusion Elevated serum VEGF and apelin levels and reduced HO-1 levels are associated with the progression of DR,and the three combination helps predict the occurrence of PDR.
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Objective To observe the serum betatrophin levels in patients with type 2 diabetes mellitus (T2DM) and to explore the role of betatrophin in the pathogenesis of diabetic retinopathy (DR).Methods A total of 59 patients with T2DM (DM group) and 14 healthy controls (NC group) were enrolled in the study.Vision,slit lamp microscope,indirect ophthalmoscope,fluorescein fundus angiography were performed on all the subjects.According to the results of the examination combined with the international DR clinical staging criteria,the patients were divided into no DR (Non-DR) group,non-proliferative DR (NPDR) group,and proliferative DR (PDR) group,with 30,20 and 9 patients in each,respectively.The fasting blood glucose (FPG),insulin (FIN),C-peptide,glycated hemoglobin (HbA1c),total cholesterol (TC),triglyceride (TG),high-density lipoprotein (HDL-C),low-density lipid Protein (LDL-C) levels were detected.The level of betatrophin in serum was determined by enzyme-linked immunosorbent assay.The correlation between betatrophin and other indicators was analyzed by Spearman correlation.The influencing factors of PDR were analyzed by logistic regression.Results Compared with subjects in the NC group,the level of FPG (F=-4.316,P<0.001),FIN (F=2.142,P=0.001),HbA1c (F=-5.726,P<0.001),TC (t=3.609,P=-0.010),LDL-C (t=0.000,P=0.003),and betatrophin (F=-2.263,P=0.024) were significantly increased and HDL-C level (F=-3.924,P<0.001) was decreases in the DM group.The difference of TG level between two groups was not statistically significant (F=-1.422,P=0.155).Compared with the Non-DR group and the NPDR group,the serum C-peptide (F=7.818,P=0.020) and betatrophin levels (F=1 2.141,P=0.002) were significantly increased in the PDR group.Spearman correlation analysis showed that the levels of betatrophin in the DM group was positively correlated to TC (r=0.304,P=0.019).The serum levels of betatrophin was positively correlated to body mass index in the Non-DR group (r=0.513,P=0.004).Furthermore,in the PDR group,a significant positive correlation was observed between the serum betatrophin levels and diastolic blood pressure (r=0.685,P=0.042).Logistic regression analysis showed that the duration of diabetes,serum C-peptide and betatrophin levels were risk factors for PDR.After controlling for the duration and serum C-peptide,the PDR risk for betatrophin levels great than or equal to 1.0 ng/ml was 12 times as much as betatrophin levels less than 1.0 ng/ml in T2DM patients.Conclusions The serum betatrophin content of patients with T2DM is abnormal.Betatrophin may be involved in the occurrence and development of PDR.
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Objective To observe RNA-Seq analysis ofgene expression profiling in retinal vascular endothelial cells after anti-vascular endothecial growth factor (VEGF) treatment.Methods Retinal vascular endothelial cells were cultured in vitro,and the logarithmic growth phase cells were used for experiments.The cells were divided into the control group and high glucose group.The cells of two groups were cultured for 5 hours with 5,25 mmol/L glucose,respectively.And then,whole transcriptome sequencing approach was applied to the above two groups of cells through RNA-Seq.Now with biological big data obtained as a basis,to analyze the differentially expressed genes (DEGs).And through enrichment analysis to explain the differential functions of DEGs and their signal pathways.Results The gene expression profiles of the two groups of cells were obtained.Through analysis,449 DEGs were found,including 297 upregulated and 152 downregulated ones.The functions of DEGs were influenced by regulations over molecular biological process,cellular energy metabolism and protein synthesis,etc.Among these genes,ITGB 1BP2,NCF 1 and UNC5C were related to production of inflammation;AKR1C4,ATP 1A3,CHST5,LCTL were related to energy metabolism of cells;DAB 1 and PRSS55 were related to protein synthesis;SMAD9 and BMP4 were related to the metabolism of extracellular matrix.GO enrichment analysis showed that DEGs mainly act in three ways:regulating biological behavior,organizing cellular component and performing molecular function,which were mainly concentrated in the system generation of biological process part and regulation of multicellular organisms.Pathway enrichment analysis showed that gene expressions of the two cell groups were differentiated in transforming growth factor-β (TGF-β) signaling pathway,complement pathway and amino acid metabolism-related pathways have also been affected,such as tryptophan,serine and cyanide.Among them,leukocyte inhibitory factor 9 and bone morphogenetic protein 4 play a role through the TGF-β signaling pathway.Conclusions High glucose affects the function of retinal vascular endothelial cells by destroying transmembrane conduction of retinal vascular endothelial cells,metabolism of extracellular matrix,and transcription and translation of proteins.
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Diabetic retinopathy is a serious complication of diabetes and is the leading cause of blindness in people with diabetes.At present,there are many views on the pathogenesis of diabetic retinopathy,including the changes of retinal microenvironment caused by high glucose,the formation of advanced glycation end products,oxidative stress injury,inflammatory reaction and angiogenesis factor.These mechanisms produce a common pathway that leads to retinal degeneration and microvascular injury in the retina.In recent years,cell regeneration therapy plays an increasingly important role in the process of repairing diseases.Different types of stem cells have neurological and vascular protection for the retina,but the focus of the target is different.It has been reported that stem cells can regulate the retinal microenvironment and protect the retinal nerve cells by paracrine production,and can also reduce immune damage through potential immunoregulation,and can also differentiate into damaged cells by regenerative function.Combined with the above characteristics,stem cells show the potential for the repair of diabetic retinopathy,this stem cell-based regenerative therapy for clinical application provides a pre-based evident.However,in the process of stem cell transplantation,homogeneity of stem cells,cell delivery,effective homing and transplantation to damaged tissue is still a problem of cell therapy.
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Objective To observe the correlation between postmenopausal estrogen levels and diabetic retinopathy (DR) in women.Methods Thirty-nine menopause female patients with type 2 diabetes mellitus and 17 menopause subjects (control group) were enrolled in this study.Control subjects aged from 53 to 82 years,with the mean age of (69.80± 8.32) years.Diabetes mellitus patients aged from 56 to 84 years,with the mean age of (70.50±8.27) years;diabetes duration ranged from 3 to 23 years,with the average course of diabetes (11.40± 7.97) years.DR diagnosis was according to the results of fundus fluorescein angiography,and thus the 39 patients were divided into DR group (19 patients) and non-DR (NDR) group (20 patients).There was no significant difference in age and menopause duration between the three groups (t=0.347,0.485;P>0.05).There was significant difference in diabetes course (t=2.748,P<0.05).Compared with NDR group,fasting blood glucose (FBG),glycosylated hemoglobin (HbAlc),total cholesterol (TC),triglyceride (TG),low density lipoprotein cholesterol (LDL-C) were significantly increased (t=6.130,5.322,4.574,2.426,4.033),high density lipoprotein cholesterol (HDL-C) was significantly lower (t=3.917),the difference was statistically significant (P<0.05).The level of estradiol (E2) was measured by radioimmunoassay.The differences of E2 levels between the three groups were compared.Logistic regression analysis was used to analyze the influencing factors of DR.Results The levels of E2 in control group,DR group and NDR group were (42.38 ±8.64),(21.49 ± 9.81) and (32.72 ± 10.51) pg/ml,respectively.The level of E2 in DR group was significantly lower than that in NDR group and control group (t=3.443,10.110;P<0.05).Logistic regression analysis showed that the duration of diabetes mellitus [coefficients =0.166,odds ratio (OR)=1.181,P=0.016],FBG (coefficients=1.162,OR=4.014,P=0.001),TC (coefficients=3.212,OR=10.820,P=0.002),TG (coefficients=1.649,OR=5.203,P=0.030) and LDL-C(coefficients=1.605,OR=4.976,P=0.003) were the risk factors for DR;E2 (coefficients=-0.100,OR=0.904,P=0.004) and HDL-C (coefficients=-4.460,OR=0.012,P=0.002) were the protective factors for DR.Conclusion The estrogen level of postmenopausal women have a certain correlation with the development of DR,it may be one of the protective factor of DR.
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The exact pathophysiological mechanisms of diabetic retinopathy (DR) remain elusive.The inflammatory reaction,retinal vascular leakage and retinal neovascularization are main features of DR.Adiponectin (APN) is an endogenous biological active protein secreted by adipocytes.It can increase insulin sensitivity,regulate blood glucose and lipid metabolism,and has anti-inflammation and anti-neovascularization functions.It may be involved in the development of DR.This review summarized the studies on the association between APN and DR in recent years.
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Microvesicles (MVs) is small membrane vesicles released from different cell types under different conditions.Studies have shown that MVs may mediate vascular inflammation,angiogenesis,and other pathological processes.MVs may play an important role in the pathogenesis of diabetic retinopathy (DR) by mediating endothelial cell injury,thrombosis and neovascularization.The plasma MV level may be an effective parameter to monitor the development of DR.This article will summarize the research progress of the relationship between MVs and DR in recent years.
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Objective To measure the concentration of serum transthyretin (TTR) of patients with different stages of diabetic retinopathy (DR).Methods A total of 176 patients with diabetes mellitus were included in this study.There were 104 males and 72 females.The patients aged from 21 to 74 years,with the mean age of(56± 11) years.The diabetes duration raged from 1 to 30 years,with the mean diabetes duration of (10 ± 7) years.The HbA 1C was 5.2%-14.1%,with the mean HbA 1C of (8.6 ± 2.0)%.According to the fundus examination,58 patients had DR (33.0%),but the other 118 patients not (67.0%).For these DR patients,10 patients were in stage Ⅰ (5.7%),26 patients in stage Ⅱ (14.8%),8 patients in stage Ⅲ (4.5%),and 14 patients in stage Ⅳ (8.0%).The concentration of serum TTR was measured by enzyme-linked immunosorbentassay kit.The differences in the concentration of serum TTR between different DR stages were compared.Bivariate analysis was used to analyze the influencing factors of TTR.Results The concentrations of serum TTR of the patients without DR or with DR of stage Ⅰ to Ⅳ were (224.96±65.47),(383.68± 102.99),(247.44±63.21),(228.2 ± 45.89),(189.34± 70.12) mg/L,respectively.The difference between different DR stages was statistically significant (F=14.690,P< 0.001).Bivariate analysis showed that the concentration of TTR was correlation to DR (r=0.179,P=0.017).There was no correlation between the concentration of TTR and diabetes duration (r=-0.027,P=0.727),hypertension (r=0.018,P=0.810),hyperlipoidemia (r=0.101,P=0.182),and the use of insulin (r=-0.032,P=0.675).Conclusion The concentration of serum TTR was increased in early DR patients,and gradually decreased with the progression of DR.The concentration of TTR is correlated to DR.
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Objective To investigate the relationship between subclinical hypothyroidism (SCH) and diabetic retinopathy (DR) in patients with type 2 diabetes mellitus (T2DM).Methods A total of 792 patients of T2DM were enrolled in the study.There were 448 males and 344 females,with an average age of (54.13 ± 13.06)years.The average duration of diabetes was (8.03 4±6.70) years.The patients were grouped according to the degree of DR and thyroid function.Among them,483 patients (61.0%) were no DR,240 patients (30.3%) were mild DR,69 patients (8.7%) were severe DR.725 patients (91.5%) were normal thyroid function,67 patients (8.5%) were SCH.The prevalence of SCH among no DR group,mild DR group and severe DR group was compared.And the prevalence of DR between normal thyroid function group and SCH group was compared.Logistic regression analysis was used to estimate the association between SCH and DR.Results No significant differences among the three groups (no DR group,mild DR group,severe DR group) were found in the prevalence of SCH (x2=1.823,P=0.402).There were no significant differences in the incidences of DR between normal thyroid function group and SCH group (x2=1.618,P=0.239).Logistic regression analysis demonstrated that SCH was not significant associated with DR [mild DR:odds ratio (OR)=1.361,95% confidence interval (CI)=0.773-2.399,P=0.286;severe DR:OR=1.326,95%CI=0.520-3.384,P=0.555;DR:OR=1.353,95% CI=0.798-2.294,P=0.261).Conclusion SCH is not significant associated with DR in patients with T2DM.
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O-linked N-acetylglucosamine (O-GlcNAc) glycosylation is an important form of posttranslational protein modification,mainly intracellular.It is closely related to cellular signaling pathways,and is involved in signal transduction,gene transcription and other important biological processes.Studies have found that O-GlcNAc glycosylation is directly related with diabetic retinopathy (DR),further studies may help us to uncover the DR mechanism,and develop new strategies for the diagnosis and treatment of this disease.
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It is clear that genetic background contributes to the development and progression of diabetic retinopathy (DR).However,the identification of susceptibility loci through candidate gene approaches,linkage disequilibrium analysis of case-control data and genome wide association study is still in its infancy and faces many challenges due to the complexity of the disease itself.China has rich resources of clinical samples.In order to facilitate elucidating the susceptibility genes of DR in China,we look forward multi-disciplinary,multi-regional collaboration studies integrating novel technologies,such as proteomics,metabolomics and next-generation sequencing to analyze gene-gene and gene-environment interaction factors comprehensively.
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Objective To determine the association of-429T/C and G1704T polymorphisms in the receptor for advanced glycation end products gene with proliferative diabetic retinopathy (PDR).Methods Case-control study.From the Beijing Desheng Diabetic Eye Study cohort of 1467 patients with type 2 diabetes mellitus (T2DM),a total of 97 patients with PDR and 105 diabetic patients without retinopathy (DWR,duration of diabetes 15 years) were included for this study.Questionnaires were collected and general ophthalmologic examinations were performed.Biochemical analysis was conducted.DNA was extracted from peripheral venous blood.The-429T/C and G1704T single nucleotide polymorphisms were detected by the means of PCR-restrication fragment length polymorphisms.Results The frequency distribution of-429T/C in DWR group was 81.0% in TT,16.1% in TC,2.9% in CC.The frequency distribution of-429T/C in PDR group was 77.3% in TT,20.6% in TC,2.1% in CC.There was no significant statistical difference between the two groups (x2 =0.40,P>0.05).Frequency of the-429T/C minor allele C in the DWR and PDR group were 11.0% and 12.4%,respectively,with no significant statistical difference between the two groups (x2 =0.20,P>0.05).The frequency distribution of G1704T in DWR group was 66.7% in GG,29.5% in GT,3.8% in TT.The frequency distribution of G1704T in PDR group was 78.4% in GG,21.6% in GT.There was no significant statistical difference between the two groups (x2 =3.44,P>0.05).Frequency of the G1704T minor allele T in the DWR and PDR group were 18.6 % and 10.8 %,respectively,in which significant difference was found within the two groups (x2 =4.79,OR=1.88,95%CI:1.06-3.33,P<0.05).Conclusions G1704T polymorphism is associated with PDR presence and 1704G allele may increase the risk of PDR.
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Dyslipidemia plays an important role in the pathogenesis of diabetic retinopathy (DR).A preliminary study found that low-density lipoprotein cholesterol,apolipoprotein (Apo) B and Apo B / Apo A1 ratio were positively correlated with DR,while high-density lipoprotein cholesterol,Apo A1 was negatively correlated with DR and proliferative DR.Reducing the blood fats to be helpful to DR control.However,the mechanism of hyperlipidemia in the pathogenesis of DR,the reason of dyslipidemia in diabetic patients and the interaction between hyperglycemia and hyperlipidemia in DR are not clear yet.Moreover,there is no predictive indicators related to blood lipid for DR.Understanding the relationship between dyslipidemia and DR can provide definite evidence for fat-reducing therapy for DR control.
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Objective To observe the genetic predisposition of complement C5 gene polymorphisms in proliferative diabetic retinopathy (PDR) in Chongqing Han population.Methods 400 type 2 diabetes (T2D) patients (case group) and 600 age-and sex-matched healthy controls (control group) were enrolled in this study.There were 8 PDR patients in case group.All the subjects were Han ethnic people.The immune-related representative SNP locus of C5 gene including rs2269067,rs7040033,rs7027797 were screened by linkage disequilibrium analysis.Locus rs1017119 was selected by TagSNP and was around the above three loci.Subjects' peripheral venous blood was collected and DNA was extracted.Genotyping was examined by PCR-restriction fragment length polymorphism method.The level of C5 plasma protein was measured by enzyme-linked immunoabsorbent assay.Results The frequency of GG genotype of rs2269067 was significantly increased in PDR patients in cases group compared with controls (Pc=3.4 × 10-5,OR=1.87,95%CI=1.43-2.44;P=3.1 × 10-6).There was no differences in frequency of G,CC and CG genotype of rs2269067 between two groups (P=1.4 × 10-4,1.000,1.0 × 10-6).There were no differences in frequency of G,CC,CG,GG genotype of rs7040033,rs1017119,and rs7027797 between two groups (P>0.05).The production of C5 plasma protein was significantly increased in case group as compare with control group (P=0.0004).An increased production of C5 plasma protein was observed in rs2269067 GG genotype cases compared to CG or CC cases (P=0.003,0.001).Conclusion C5 rs2269067 GG genotype may be associated with the PDR of T2D in Chongqing Han population.
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Objective To assess the association of vascular endothelial growth factor (VEGF) gene-460C/T and-634C/G polymorphism with diabetic retinopathy (DR) among patients in Asia and European by meta-analysis.Methods A systematic search of electronic databases (PubMed,Cochrane Library,EMBASE,VIP,Wanfang technological,CNKI,etc.) was carried out until Jun,2014.Case-control studies on the relationship between genetic polymorphism of VEGF-460C/T and VEGF-634C/G with diabetic retinopathy were included in this analysis.The data were quantitatively analyzed by RevMan 5.0 software after assessing the quality of included studies.The pooled odds ratios (OR) and their corresponding 95% confidence intervals (CI) were used to assess the strength of the association.Results VEGF-460C/T (7 studies:899 cases and 786 controls) and VEGF-634C/G (10 studies:1615 cases and 1861 controls) were inclued in this meta-analysis.Significant association was found for-460C/T polymorphism in Aisa (C versus T:OR=1.52,95%CI was [1.22,1.90],Z=3.72,P=0.0002;CC versus CT+TT:OR=1.61,95%CI was [1.19,2.19],Z=3.05,P=0.002;TT versus CT+CC:OR=0.64,95%CI was [0.41,0.98],Z=2.07,P=0.04),and VEGF-634CC gene type was associated with DR in European (OR=1.56,95%CI [1.08,2.25],Z=2.37,P=0.02).No significant publication bias was found.Conclusions The metaanalysis demonstrated that DR was associated with VEGF-460C/T polymorphism in Asia,and C alleles and CC gene type was the risk polymorphism;VEGF-634C/G polymorphism was not associated with DR,but its CC genotype maybe the risk factor in European.Further case-control studies based on larger sample size are still needed,especially for-634C/G polymorphism.
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Objective To investigate if insulin can affect the expression of vascular endothelial growth factor (VEGF) in the retina of streptozotocin-induced diabetic rats. Methods A total of 60 male Sprague-Dawley rats were randomly divided into sodium citrate buffer control group (CIT-CON, n= 30) and STZ-induced diabetic group (STZ-DM, n=30). At the 16th week, 24 rats from CIT-CON group at random were randomly divided to group A (sodium citrate buffer control group, n = 12) and group B (sodium citrate buffer plus insulin group, n= 12). The remaining 6 rats from as CIT-CON group served as negative control. At the same time, 24 rats from STZ-DM group at random were randomly divided to group C (STZ-induced diabetic group, n= 12) and group D (STZ-induced diabetic plus insulin group, n= 12). The remaining 6 rats from STZ-DM group also served as negative control. 4 IU of insulin was injected subcutaneously to rats of group B and D. Immunohistochemistry, Western blot and Real-time polymerase chain reaction (RT-PCR) were used to measure the expression level of VEGF protein and mRNA respectively. RESULTS Insulin significantly increased the VEGF mRNA (7.71 ± 0.25 vs 5.36 ±0. 37, t test P< 0. 05) and protein expression (0. 4925 ± 0. 0122 vs 0. 4272 ± 0. 0110, t test P< 0. 05) in the retina of CIT-CON rats.However, in retina of STZ-DM rats, insulin had no effect on VEGF mRNA (8. 92±0. 27 vs 9. 05±0. 28, t test, P>0. 05) and protein expression (0. 5152±0. 0109 vs 0. 5099±0. 0100, t test P>0.05). Conclusions Insulin had no effect on VEGF expression in the retina of STZ-DM rats.
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The pathogenesis of diabetic retinopathy (DR) is more complex. For the upstream of traditional pathogenesis, to looking for unifying mechanism theory which proposed in foundation of common promoters and the latest view of DR may be the result of chronic inflammation. Both of them provide the basic and clinical theraby of DR with new direction. Therefore, there are many related issuess till needs to intensive study.
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Objective To analyze the expression of apoptosis-relared genes of retinal blood vessel in early diabetic rats by gene chip technology. Methods To make diabetic rat model by intraperitoneal injection of streptozotocin (STZ). On the 6th week after blood pressure increased, 10 rats were executed in Diabetic group and normal control group respectively. 20 retinal blood vessels were extracted and the RNA was isolated. The probe was made of α-32 P-deoxyadenosine triphosphate (dATP)-labeled sample which hybridized 1176 nylon chips, and then analyzed by software. Three different expression genes were selected to verify by reverse transcription polymerase chain reaction (RT-PCR). Results On the 6th week, 136 (11.5%)genes were differentially expressed [up-regulated genes were 90 (7.6%), down- regulated genes were 46(3.9%)] in diabetic group. These genes involved into different groups according to their function. Especially in 72 apoprosis-related genes, 15 genes were differentially expressed. The up- regulated genes were some TNF receptor family members such as TNFRSF12, TRAIL, TNFRSF9, FADD;Bcl-2 family members such as bcl-w, bax, bakl and AKT. The down-regulated genes were FAF1 which related to fas. Conclusions The expression of retinal vascular gene in early diabetic rats has been changed complicatedly. In particular, the multiple apoptosis-related genes have been changed in early diabetic, and most of them are at the upstream of apoptosis pathway. These findings indicate that the development of diabetic retinopathy is associated with multiple signaling pathways leading to apoptosis, while the alterations on the level of molecular biochemistry are still limited in apoptosis induction period.