A competing risk analysis of sequential complication development in Asian type 2 diabetes mellitus patients

Cost-Effectiveness of Glucose-Lowering Therapies as Add-on to Standard Care for People With Type 2 Diabetes in Malaysia

OBJECTIVES

This study aims to evaluate the cost-effectiveness of various glucose-lowering therapies as add-on to standard care for people with type 2 diabetes (T2D) in Malaysia.

METHODS

A state-transition microsimulation model was developed to compare the clinical and economic outcomes of 4 treatments: standard care, dipeptidyl peptidase-4 inhibitors, sodium-glucose cotransporter-2 inhibitors (SGLT2is), and glucagon-like peptide-1 receptor agonists. Cost-effectiveness was assessed from a healthcare provider's perspective over a lifetime horizon with 3% discount rate in a hypothetical cohort of people with T2D. Data input were informed from literature and local data when available. Outcome measures include costs, quality-adjusted life-years, incremental cost-effectiveness ratios, and net monetary benefits. Univariate and probabilistic sensitivity analyses were performed to assess uncertainties.

RESULTS

Over a lifetime horizon, the costs to treat a person with T2D ranged from RM 12 494 to RM 41 250, whereas the QALYs gains ranged from 6.155 to 6.731, depending on the treatment. Based upon a willingness-to-pay threshold of RM 29 080 per QALY, we identified SGLT2i as the most cost-effective glucose-lowering treatment, as add-on to standard care over patient's lifetime, with the net monetary benefit of RM 176 173 and incremental cost-effectiveness ratios of RM 12 279 per QALY gained. The intervention also added 0.577 QALYs and 0.809 LYs compared with standard care. Cost-effectiveness acceptability curve showed that SGLT2i had the highest probability of being cost-effective in Malaysia across varying willingness-to-pay threshold. The results were robust to various sensitivity analyses.

CONCLUSIONS

SGLT2i was found to be the most cost-effective intervention to mitigate diabetes-related complications.

Nomogram for prediction of severe community-acquired pneumonia development in diabetic patients: a multicenter study

Background

Diabetic patients with community-acquired pneumonia (CAP) have an increased risk of progressing to severe CAP. It is essential to develop predictive tools at the onset of the disease for early identification and intervention. This study aimed to develop and validate a clinical feature-based nomogram to identify diabetic patients with CAP at risk of developing severe CAP.

Method

A retrospective cohort study was conducted between January 2019 to December 2020. 1026 patients with CAP admitted in 48 hospitals in Shanghai were enrolled. All included patients were randomly divided into the training and validation samples with a ratio of 7:3. The nomogram for the prediction of severe CAP development was established based on the results of the multivariate logistic regression analysis and other predictors with clinical relevance. The nomogram was then assessed using receiver operating characteristic curves (ROC), calibration curve, and decision curve analysis (DCA).

Results

Multivariate analysis showed that chronic kidney dysfunction, malignant tumor, abnormal neutrophil count, abnormal lymphocyte count, decreased serum albumin level, and increased HbA1c level at admission was independently associated with progression to severe CAP in diabetic patients. A nomogram was established based on these above risk factors and other predictors with clinical relevance. The area under the curve (AUC) of the nomogram was 0.87 (95% CI 0.83–0.90) in the training set and 0.84 (95% CI 0.78–0.90). The calibration curve showed excellent agreement between the predicted possibility by the nomogram and the actual observation. The decision curve analysis indicated that the nomogram was applicable with a wide range of threshold probabilities due to the net benefit.

Conclusion

Our nomogram can be applied to estimate early the probabilities of severe CAP development in diabetic patients with CAP, which has good prediction accuracy and discrimination abilities. Since included biomarkers are common, our findings may be performed well in clinical practice and improve the early management of diabetic patients with CAP.

Development and assessment of diabetic nephropathy prediction model using hub genes identified by weighted correlation network analysis

Diabetic nephropathy (DN) is one microvascular complication of diabetes. About 30% of diabetic patients can develop DN, which is closely related to the high incidence and mortality of heart diseases, and then develop end-stage renal diseases. Therefore, early detection and screening of high-risk patients with DN is important. Herein, we explored the differences of serum transcriptomics between DN and non-DN in type II diabetes mellitus (T2DM) patients. We obtained 110 target genes using weighted correlation network analysis. Gene Ontology enrichment analysis indicates these target genes are mainly related to membrane adhesion, alpha-amino acid biosynthesis, metabolism, and binding, terminus, inhibitory synapse, clathrinid-sculpted vesicle, kinase activity, hormone binding, receptor activity, and transporter activity. Kyoto Encyclopedia of Genes and Genomes analysis indicates the process of DN in diabetic patients can involve synaptic vesicle cycle, cysteine and methionine metabolism, N-Glycan biosynthesis, osteoclast differentiation, and cAMP signaling pathway. Next, we detected the expression levels of hub genes in a retrospective cohort. Then, we developed a risk score tool included in the prediction model for early DN in T2DM patients. The prediction model was well applied into clinical practice, as confirmed by internal validation and several other methods. A novel DN risk model with relatively high prediction accuracy was established based on clinical characteristics and hub genes of serum detection. The estimated risk score can help clinicians develop individualized intervention programs for DN in T2DM. External validation data are required before individualized intervention measures.

Raman studies of the adipose tissue: Current state-of-art and future perspectives in diagnostics

The last decades revealed that the adipose tissue shows an unexplored therapeutic potential. In particular, targeting the perivascular adipose tissue (PVAT), that surrounds blood vessels, can prevent cardiovascular pathologies and browning of the adipose tissue can become an effective strategy against obesity. Therefore, new analytical tools are necessary to analyze this tissue. This review reports on the recent developments of various Raman-based techniques for the identification and quantification of the adipose tissue compared to conventional analytical methods. In particular, the emphasis is on analysis of PVAT, investigation of pathological changes of the adipose tissue in model systems and possibilities for its characterization in the clinical context. Overall, the review critically discusses the potential and limitations of Raman techniques in adipose tissue-targeted diagnostics and possible future anti-obesity therapies.

Economic evaluation of population-based type 2 diabetes mellitus screening at different healthcare settings in Vietnam

Introduction

Few economic evaluations have assessed the cost-effectiveness of screening type-2 diabetes mellitus (T2DM) in different healthcare settings. This study aims to evaluate the value for money of various T2DM screening strategies in Vietnam.

Methods

A decision analytical model was constructed to compare costs and quality-adjusted life years (QALYs) of T2DM screening in different health care settings, including (1) screening at commune health station (CHS) and (2) screening at district health center (DHC), with no screening as the current practice. We further explored the costs and QALYs of different initial screening ages and different screening intervals. Cost and utility data were obtained by primary data collection in Vietnam. Incremental cost-effectiveness ratios were calculated from societal and payer perspectives, while uncertainty analysis was performed to explore parameter uncertainties.

Results

Annual T2DM screening at either CHS or DHC was cost-effective in Vietnam, from both societal and payer perspectives. Annual screening at CHS was found as the best screening strategy in terms of value for money. From a societal perspective, annual screening at CHS from initial age of 40 years was associated with 0.40 QALYs gained while saving US$ 186.21. Meanwhile, one-off screening was not cost-effective when screening for people younger than 35 years old at both CHS and DHC.

Conclusions

T2DM screening should be included in the Vietnamese health benefits package, and annual screening at either CHS or DHC is recommended.

Role of circRNA-miRNA-mRNA interaction network in diabetes and its associated complications

The majority of the non-protein-coding RNAs are being identified with diversified functions that participate in cellular homeostasis. The circular RNAs (circRNAs) are emerging as noncoding transcripts with a key role in the initiation and development of many physiological and pathological conditions. The advancements in high-throughput RNA sequencing and bioinformatics tools help us to identify several circRNA regulatory pathways, one of which is microRNA (miRNA)-mediated regulation. Besides the direct influence over mRNA transcription, the circRNA can also control the target's expression via sponging miRNAs or the RNA-binding proteins. Studies have demonstrated the dysregulation of the circRNA-miRNA-mRNA interaction network in the pathogenesis of many diseases, including diabetes. This intricate mechanism is associated with the pathogenesis of diabetes and its complications. This review will focus on the circRNA-miRNA-mRNA interaction network that influences the gene expression in the progression of diabetes and its associated complications.

Factors associated with influenza vaccine coverage among patients with diabetes: Korea National Health and Nutrition Examination Survey 2016-2018

Background

Although the influenza vaccine has been proven to be effective, this common disease has high morbidity and mortality rates. Moreover, adults with diabetes are at a high risk of influenza-mediated morbidity and mortality.

Purpose of the study

With the increasing prevalence of diabetes, influenza is more lethal in diabetics; thus, we aimed to investigate the factors associated with influenza vaccination coverage in patients with diabetes.

Methods

Cross-sectional data were obtained from the Korea National Health and Nutrition Examination Survey (2016–2018). We retrospectively analyzed whether sociodemographic, health-related, and medical factors are associated with influenza vaccination coverage in patients with diabetes. We performed a complex sample logistic regression analysis and estimated the odds ratios (ORs) by adjusting for statistically significant factors.

Results

The number of survey subjects was 18,553. The vaccine coverage rate among patients with diabetes was 60.6%. In the univariate analysis, sex, educational level, smoking, exercise, drinking, marital status, private health insurance, activity limit, economic activity, age, and EuroQol-5 Dimension scores, which were used to assess health-related quality of life, were associated with vaccination coverage. In the multivariate analysis, only age and economic activity were associated with vaccination coverage. The vaccination coverage rate was higher for people who did not undertake economic activities and who were older (OR 1.512 (1.087–2.105), OR 2.212 (1.822–2.686), respectively, p < 0.001).

Conclusion

National interventions involving public health centers are necessary to encourage influenza immunization for patients with diabetes, especially younger patients and those who work or undertake economic activities.

Comparing the incidence of major cardiovascular events and severe microvascular complications in patients with type 2 diabetes mellitus: A systematic review and meta-analysis

BACKGROUND

Type 2 diabetes mellitus (T2DM) causes both macrovascular and microvascular complications. However, currently, selection of glycemic measures and their thresholds to diagnose T2DM, and efficacy outcomes in evaluation of anti-diabetic drugs is predominantly informed by the relation of T2DM to microvascular complications. We can be severely mistaken on T2DM by neglecting macrovascular complications which are generally more severe, if they also occur more commonly than microvascular complications.

AIM

To compare the incidence of major cardiovascular events (MACEs) and severe microvascular complications (SMICs) in T2DM patients.

METHODS

MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials were searched from inception to September 2017. Cohort studies or trials of T2DM patients aged 18 years or older that reported incidence of both MACEs and SMICs were included. MACEs were defined as nonfatal myocardial infarction and stroke, and cardiovascular death, while SMICs included serious retinopathy, nephropathy and diabetic disorder. The relative risk (RR) was estimated as the incidence of MACEs divided by that of SMICs in same patients and combined with meta-analysis in a random-effect model.

RESULTS

Twelve studies with a total of 16 cohorts and 387376 patients were included, and the combined RR was 2.02 (95%CI: 1.46–2.79). The higher incidence of MACEs remained in various subgroup and sensitivity analyses.

CONCLUSION

Patients with T2DM are much more likely to develop MACEs than SMICs. By taking more serious consequences and relatively higher incidence into consideration, macrovascular complications deserve more emphasis in developing the diagnostic criteria of T2DM and in evaluating the efficacy of anti-diabetic drugs.

Temporal trajectories of accompanying comorbidities in patients with type 2 diabetes: a Korean nationwide observational study

Type 2 diabetes mellitus is a major concern globally and well known for increasing risk of complications. However, diabetes complications often remain undiagnosed and untreated in a large number of high-risk patients. In this study based on claims data collected in South Korea, we aimed to explore the diagnostic progression and sex- and age-related differences among patients with type 2 diabetes using time-considered patterns of the incidence of comorbidities that evolved after a diagnosis of type 2 diabetes. This study compared 164,593 patients who met the full criteria for type 2 diabetes with age group-, sex-, encounter type-, and diagnosis date-matched controls who had not been diagnosed with type 2 diabetes. We identified 76,423 significant trajectories of four diagnoses from the dataset. The top 30 trajectories with the highest average relative risks comprised microvascular, macrovascular, and miscellaneous complications. Compared with the trajectories of male groups, those of female groups included relatively fewer second-order nodes and contained hubs. Moreover, the trajectories of male groups contained diagnoses belonging to various categories. Our trajectories provide additional information about sex- and age-related differences in the risks of complications and identifying sequential relationships between type 2 diabetes and potentially complications.

Activation of ALDH2 attenuates high glucose induced rat cardiomyocyte fibrosis and necroptosis

Necroptosis is one of a regulated programmed death mode, fibrosis is closely related with cell death. It has been reported that inhibition of necroptosis can play the protective role in cardiac ischemia and reperfusion injury, stroke and other diseases, but the mechanisms of aldehyde dehydrogenases 2 (ALDH2) against high glucose induced neonatal rat ventricular primary cardiomyocytes fibrosis and necroptosis had not been elucidated clearly. This study was to observe the effect of ALDH2 on high glucose (HG) induced myocardial fibrosis and necroptosis in primary rat cardiomyocytes model. In contrast to normal glucose group, in HG group, with the decreases of ALDH2 activity, mRNA and protein levels, the cardiomyocytes viability was decreased, reactive oxygen species (ROS), the inflammation factors - tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β) levels, collagen I (col I) and col III mRNA expressions and tissue inhibitors of matrix metalloproteinase 4 (TIMP4) protein expression were increased, while matrix metalloproteinase 14 (MMP14) protein level, the ratio of MMP14/TIMP4 were decreased, and the necroptosis key factors - the receptor interacting protein 1 (RIP1), RIP3 and mixed lineage kinase domain-like protein (MLKL) at mRNA and protein expressions were increased, the inflammasome core proteins - NLRP3 and ASC protein expressions were also increased, the apoptosis rate and necrosis rate were also increased. When the cardiomyocytes were treated with Alda-1 (the ALDH2 agonist) in HG intervention, the cell viability, ALDH2 activity, mRNA and protein levels, MMP14 protein level, the ratio of MMP14/TIMP4 were higher, ROS and TNF-α, IL-6, IL-1β levels, RIP1, RIP3, MLKL, NLRP3 and ASC expressions, col I and col III, TIMP4 expressions, the apoptosis rate and necrosis rate were lower than in HG group. Daidzin, the antagonist of ALDH2 abolished the role of Alda-1. In summary, ALDH2 maybe is a key regulator in high glucose induced cardiomyocytes injury. Activation of ALDH2 prevented the happening of fibrosis, apoptosis and necroptosis in high glucose induced primary cardiomyocytes injury model, the protective effects were related to the inhibiting of oxidative stress and inflammation, changing of MMP14 and TIMP4, then inhibiting the happening of fibrosis, apoptosis and necroptosis. These findings advance our understanding of the intensive mechanisms of ALDH2's cardioprotection, and provide the targeted basis for clinical diabetes treatment.

Diabetes Mellitus and Cause-Specific Mortality: A Population-Based Study

BACKGROUND

To investigate whether diabetes contributes to mortality for major types of diseases.

METHODS

Six National Health and Nutrition Examination Survey data cycles (1999 to 2000, 2001 to 2002, 2003 to 2004, 2005 to 2006, 2007 to 2008, and 2009 to 2010) and their linked mortality files were used. A population of 15,513 participants was included according to the availability of diabetes and mortality status.

RESULTS

Participants with diabetes tended to have higher all-cause mortality and mortality due to cardiovascular disease, cancer, chronic lower respiratory diseases, cerebrovascular disease, influenza and pneumonia, and kidney disease. Confounder-adjusted Cox proportional hazard models showed that both diagnosed diabetes category (yes or no) and diabetes status (diabetes, prediabetes, or no diabetes) were associated with all-cause mortality and with mortality due to cardiovascular disease, chronic lower respiratory diseases, influenza and pneumonia, and kidney disease. No associations were found for cancer-, accidents-, or Alzheimer's disease-related mortality.

CONCLUSION

The current study's findings provide epidemiological evidence that diagnosed diabetes at the baseline is associated with increased mortality risk due to cardiovascular disease, chronic lower respiratory diseases, influenza and pneumonia, and kidney disease, but not with cancer or Alzheimer's disease.

Severe Hypoglycemia as a Predictor of End-Stage Renal Disease in Type 2 Diabetes: A National Cohort Study

Aims: This study investigated whether there is a link between severe hypoglycemia and progression into end-stage renal disease (ESRD) in patients with type 2 diabetes. Methods: Tapping into Taiwan’s Health Insurance Research Database, we identified all type 2 diabetes patients between 1996 and 2013 and identified those diagnosed with a severe hypoglycemia episode during an emergency department visit and those who were not. Controls were then matched 1:1 for age, sex, index year, and medication. Results: We identified 468,421 type 2 diabetes patients diagnosed as having severe hypoglycemia in an emergency department visit. Compared with controls, these patients with SH had a higher risk of all-cause mortality (Hazard Ratio (HR), 1.76; 95% confidence interval, 1.61–1.94) and progressed into ESRD within a shorter period of time. Results were similar after controlling for competing risk. Conclusion: Severe hypoglycemia is significantly associated with worsening renal dysfunction in patients with type 2 diabetes and hastened progression into ESRD.

Persistence of oral antidiabetic treatment for type 2 diabetes characterized by drug class, patient characteristics and severity of renal impairment: A Japanese database analysis

AIM

To evaluate the persistence with oral antidiabetic drug (OAD) treatment characterized by drug class, patient characteristics and severity of renal impairment (RI) in patients with type 2 diabetes (T2DM) in Japan.

MATERIALS AND METHODS

This retrospective, observational study extracted data from a large-scale hospital database (April 2008 to September 2016). Patients with T2DM aged ≥40 years on the day of their first prescription (index date) of any OAD (biguanides [BGs], thiazolidinediones [TZDs], sulphonylureas [SUs], glinides, dipeptidyl peptidase-4 [DPP-4] inhibitors, or α-glucosidase inhibitors [α-GIs]) available between January 1, 2014 and September 30, 2016 were identified. Sodium-glucose co-transporter-2 inhibitors were not available at study initiation. Treatment persistence was assessed by Kaplan-Meier survival curves. Patients were also categorized by RI status using estimated glomerular filtration rate: ≥90 mL/min/1.73 m2 (G1); 60 to <90 mL/min/1.73 m2 (G2); 30 to <60 mL/min/1.73 m2 (G3); and <30 mL/min/1.73 m2 (G4+).

RESULTS

We identified 206 406 index dates from 162 116 eligible patients. The largest number of index dates (91634) was observed for DPP-4 inhibitors, followed by BGs, SUs, α-GIs, glinides and TZDs. Treatment persistence was longest for DPP-4 inhibitors (median 17.0 months, 95% confidence interval [CI] 16.4-17.5) and BGs (median 17.3 months, 95% CI 16.6-18.2), and shortest for α-GIs (median 5.6 months, 95% CI 5.4-5.9) and SUs (median 4.3 months, 95% CI 4.2-4.6). Persistence was longest with DPP-4 inhibitors at all RI stages (G1-G4+), followed by BGs at stages G1/G2.

CONCLUSIONS

The longest OAD persistence was observed for BGs and DPP-4 inhibitors at RI stages G1/G2, and for DPP-4 inhibitors at RI stages G3/G4+.

Lifetime trajectory simulation of chronic disease progression and comorbidity development

INTRODUCTION

Comorbidity is common in elderly patients and it imposes heavy burden on both individual and the whole healthcare system. This study aims to gain insights of comorbidity development by simulating the lifetime trajectory of disease progression from single chronic disease to comorbidity.

METHODS

Eight health states spanning from no chronic condition to comorbidity are considered in this study. Disease progression network is constructed based on the seven-year retrospective data of around 700,000 residents living in Singapore central region. Microsimulation is applied to simulate the process of aging and disease progression of a synthetic new-born cohort for the entire lifetime.

RESULTS

Among the 40 unique trajectories observed from the simulation, the top 10 trajectories covers 60% of the cohort. Timespan of most trajectories from birth to death is 80 years. Most people progress to at risk at late 30 s, develop the first chronic condition at 50 s or 60 s, and then progress to complications at 70 s. It is also observed that the earlier one person develops chronic conditions, the more life-year-lost is incurred.

DISCUSSION

The lifetime disease progression trajectory constructed for each person in the cohort describes how a person starts healthy, becomes at risk, then progresses to one or more chronic conditions, and finally deteriorates to various complications over the years. This study may help us have a better understanding of chronic disease progression and comorbidity development, hence add values to chronic disease prevention and management.

Impact of the pay-for-performance program on lower extremity amputations in patients with diabetes in Taiwan

Patients with diabetes are at a high risk of lower extremity amputations and may have a reduced life expectancy. Taiwan has implemented a diabetes pay-for-performance (P4P) program providing team care to improve the control of disease and avoid subsequent complications. Few studies investigated the effects of adopting a nationalized policy to decrease amputation risk in diabetes previously. Our study aimed to analyze the impact of the P4P programs on the incidence of lower extremity amputations in Taiwanese patients with diabetes.This was a population-based cohort study using the Taiwan National Health Insurance Research Database (which provided coverage for 98% of the total population in Taiwan) from 1998 to 2007. Patients with diabetes were identified based on the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) diagnostic codes. We linked procedure codes to inpatient claims to identify patients hospitalized for nontraumatic lower extremity amputations.A total of 9738 patients with diabetes with amputations were enrolled (mean age ± standard deviation: 64.4 ± 14.5 years; men: 63.9%). The incidence of nontraumatic diabetic lower extremity amputations decreased over the time period studied (3.79-2.27 per 1000 persons with diabetes). Based on the Cox proportional hazard regression model, male sex (hazard ratio: 1.83, 95% confidence interval [CI] 1.76-1.92), older age, and low socioeconomic status significantly interact with diabetes with respect to the risks of amputation. Patients who did not join the P4P program for diabetes care had a 3.46-fold higher risk of amputation compared with those who joined (95% CI 3.19-3.76).The amputation rate in Taiwanese diabetic patients decreased over the time period observed. Diabetes in patients with low socioeconomic status is associated with an increased risk of amputations. Our findings suggested that in addition to medical interventions and self-management educations, formulate and implement of medical policies, such as P4P program, might have a significant effect on decreasing the diabetes-related amputation rate.

Predictors of vascular complications among type 2 diabetes mellitus patients at University of Gondar Referral Hospital: a retrospective follow-up study

BACKGROUND

Type 2 Diabetes Mellitus is a serious metabolic disease that is often associated with vascular complications. There are 1.9 million people living with Diabetes in Ethiopia; diabetes mellitus is found to be the ninth leading cause of death related to its complications. Although the rate of vascular complications continues to rise, there is limited information about the problem. This study aimed to estimate the incidence and predictors of vascular complications among type 2 diabetes mellitus patients at University of Gondar Referral Hospital.

METHODS

Institution based retrospective follow-up study was conducted at University of Gondar Referral Hospital with 341 newly diagnosed type 2 DM patients from September 2005 to March 2017 and the data were collected by reviewing their records. Schoenfeld residuals test and interaction of each covariate with time were used to check proportional hazard assumption. The best model was selected by using Akaike Information Criteria (AIC). Hazards ratio (HR) with its respective 95% confidence interval were reported to show strength of association.

RESULT

The selected patients were followed retrospectively for a median follow up time of 81.50 months (Inter quartile range (IQR) = 67.2-103.3). The mean age (± Standard deviation (SD)) of patients at baseline was 51.7(SD: ±11.5 years) and 57.48% were females. The incidence rate of vascular complications was 40.6 cases/ 1000 person years of observation. The significant predictors for vascular complications where found to be male sex (Adjusted hazard ratio (AHR) = 0.50, 95% CI: 0.27, 0.94), having hypertension at baseline(AHR = 3.99, 95% CI: 1.87, 8.56), positive protein urea at base line (AHR = 1.69, 95% CI: 1.03, 2.78), high density lipoprotein cholesterol(HDL-C) level ≥ 40 mg per deciliter (mg/dl) (AHR = 0.43, 95% CI: 0.24, 0.77), low density lipoprotein cholesterol(LDL-C) level > 100 mg/dl (AHR = 3.05, 95% CI: 1.47, 6.35) and triglyceride > 150 mg/dl (AHR = 2.74, 95% CI: 1.28, 5.84).

CONCLUSION

The incidence of vascular complications among type 2 diabetes patients remains a significant public health problem. Hypertension at baseline, LDL-C > 100 mg/dl, triglyceride > 150 mg/dl, HDL-C ≥ 40 mg/dl and male sex were significant predictors of vascular complication. In the light of these findings targeted interventions should be given to diabetes patients with hypertension comorbidity and dyslipidemia at follow up clinics.

Effect of small molecules on cell reprogramming

The essential idea of regenerative medicine is to fix or replace tissues or organs with alive and patient-specific implants. Pluripotent stem cells are able to indefinitely self-renew and differentiate into all cell types of the body which makes them a potent substantial player in regenerative medicine. The easily accessible source of induced pluripotent stem cells may allow obtaining and cultivating tissues in vitro. Reprogramming refers to regression of mature cells to its initial pluripotent state. One of the approaches affecting pluripotency is the usage of low molecular mass compounds that can modulate enzymes and receptors leading to the formation of pluripotent stem cells (iPSCs). It would be great to assess the general character of such compounds and reveal their new derivatives or modifications to increase the cell reprogramming efficiency. Many improvements in the methods of pluripotency induction have been made by various groups in order to limit the immunogenicity and tumorigenesis, increase the efficiency and accelerate the kinetics. Understanding the epigenetic changes during the cellular reprogramming process will extend the comprehension of stem cell biology and lead to potential therapeutic approaches. There are compounds which have been already proven to be or for now only putative inducers of the pluripotent state that may substitute for the classic reprogramming factors (Oct3/4, Sox2, Klf4, c-Myc) in order to improve the time and efficiency of pluripotency induction. The effect of small molecules on gene expression is dosage-dependent and their application concentration needs to be strictly determined. In this review we analysed the role of small molecules in modulations leading to pluripotency induction, thereby contributing to our understanding of stem cell biology and uncovering the major mechanisms involved in that process.