Shi HS, Yuan X, Wu FF, Li XY, Fan WJ, Yang X, Hu XM, Liu GB. Research progress and challenges in stem cell therapy for diabetic foot: Bibliometric analysis and perspectives. World J Stem Cells 2024; 16(1): 33-53 [PMID: 38292441 DOI: 10.4252/wjsc.v16.i1.33]
Corresponding Author of This Article
Guo-Bin Liu, MD, Doctor, Department of Peripheral Vascular Surgery, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, No. 528 Zhangheng Road, Pudong New Area, Shanghai 250021, China. 15800885533@163.com
Research Domain of This Article
Peripheral Vascular Disease
Article-Type of This Article
Scientometrics
Open-Access Policy of This Article
This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Hong-Shuo Shi, Xin Yuan, Fang-Fang Wu, Xiao-Yu Li, Wei-Jing Fan, Xiao Yang, Xiao-Ming Hu, Guo-Bin Liu, Department of Peripheral Vascular Surgery, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 250021, China
Author contributions: Liu GB, Yang X, and Fan WJ proposed the research design; Shi HS and Yuan X conducted the literature search, publication screening, and data extraction; Shi HS carried out the data analysis; Wu FF and Li XY conducted manuscript revisions; Hu XM made important contributions to the editing and illustration of this manuscript; The authors collectively contributed to and endorsed the final version of the article.
Supported by: The study was funded by the National Natural Science Foundation of China (82274528); Construction Task Book for the Three-Year Action Plan for Accelerating the Inheritance and Innovative Development of Traditional Chinese Medicine in Shanghai (2021-2023) (ZY(2021-2023)-0211); Shanghai Municipal Health Commission Scientific Research Programme Mission Statement (202240228); Special Youth Project for Clinical Research of Shanghai Municipal Health Commission (20234Y0162); Clinical Research Talent Training Program of Shanghai University of Traditional Chinese Medicine Affiliated Hospital (2023LCRC06); Four Bright Foundations of Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine (SGKJ-202301); Shanghai Pudong New Area Health and Family Planning Commission’s Pudong Famous TCM Cultivation Program project (PWRZM2020-18).
Conflict-of-interest statement: The authors declare having no conflicts of interest in relation to this manuscript.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Guo-Bin Liu, MD, Doctor, Department of Peripheral Vascular Surgery, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, No. 528 Zhangheng Road, Pudong New Area, Shanghai 250021, China. 15800885533@163.com
Received: September 23, 2023 Peer-review started: September 23, 2023 First decision: November 22, 2023 Revised: December 6, 2023 Accepted: December 28, 2023 Article in press: December 28, 2023 Published online: January 26, 2024 Processing time: 121 Days and 2.1 Hours
Abstract
BACKGROUND
Stem cell therapy has shown great potential for treating diabetic foot (DF).
AIM
To conduct a bibliometric analysis of studies on the use of stem cell therapy for DF over the past two decades, with the aim of depicting the current global research landscape, identifying the most influential research hotspots, and providing insights for future research directions.
METHODS
We searched the Web of Science Core Collection database for all relevant studies on the use of stem cell therapy in DF. Bibliometric analysis was carried out using CiteSpace, VOSviewer, and R (4.3.1) to identify the most notable studies.
RESULTS
A search was conducted to identify publications related to the use of stem cells for DF treatment. A total of 542 articles published from 2000 to 2023 were identified. The United States had published the most papers on this subject. In this field, Iran’s Shahid Beheshti University Medical Sciences demonstrated the highest productivity. Furthermore, Dr. Bayat from the same university has been an outstanding researcher in this field. Stem Cell Research & Therapy is the journal with the highest number of publications in this field. The main keywords were “diabetic foot ulcers,” “wound healing,” and “angiogenesis.”
CONCLUSION
This study systematically illustrated the advances in the use of stem cell therapy to treat DF over the past 23 years. Current research findings suggested that the hotspots in this field include stem cell dressings, exosomes, wound healing, and adipose-derived stem cells. Future research should also focus on the clinical translation of stem cell therapies for DF.
Core Tip: Through the utilization of bibliometric analysis, this study systematically presented the body of research concerning stem cell therapy in diabetic foot cases, while also identifying focal points and burgeoning trends within this domain.
Citation: Shi HS, Yuan X, Wu FF, Li XY, Fan WJ, Yang X, Hu XM, Liu GB. Research progress and challenges in stem cell therapy for diabetic foot: Bibliometric analysis and perspectives. World J Stem Cells 2024; 16(1): 33-53
Diabetic foot (DF) is one of the most common complications of diabetes. Once infections and recurrences occur in DF patients, wounds are prone to deteriorate, leading to sepsis and an increased risk of amputation[1]. DF constitutes a significant contributor to disability and mortality among individuals with diabetes[2], with as many as 20% of diabetic patients requiring hospitalization due to this condition[3]. Evidence indicates that approximately 4%-10% of individuals with type 2 diabetes may experience DF ulcers (DFUs). Furthermore, the risk of mortality within a 5-year period for those affected by DF is notably elevated, as it is 2.5 times higher than the risk among diabetes patients without DF[4]. It is estimated that a diabetes-related amputation is performed every 20 s globally. The annual mortality rate for DFU patients is as high as 11%, and for amputees, it is as high as 22%[5]. Unfortunately, over the past few decades, there has been no improvement in the incidence and disability rates of DF. Traditional DF therapies have also been unsatisfactory. Moreover, standalone interventions or vascular bypass surgeries are inadequate to address the fundamental pathological mechanisms of widespread blood vessel constriction and blockage in DF as well as nerve and tissue impairments[6].
Currently, most treatment methods for DF mainly target a single factor related to wound healing. Due to advances in regenerative medicine in the clinical setting, there has been widespread interest in the potential impact of stem cells on DF[7]. As a highly promising approach for treating DF[8], the main advantage of stem cell therapy lies in its ability to comprehensively regulate tissue regeneration by improving the microenvironment[9-11]. The mechanisms that contribute to the effectiveness of stem cell therapy involve promoting the deposition of collagen, instigating the formation of new blood vessels, enhancing lower limb blood flow, and mitigating inflammation[12].
Bibliometric analysis, which focuses on the systematic and characteristic features of literature, has been widely used to qualitatively and quantitatively analyze scientific literature[13,14]. It has been extensively applied in gynecology[15], orthopedics[16], complementary and alternative medicine[17], and other medical fields. Bibliometrics serves not only as a tool for comprehensively understanding research trends and hotspots within a particular domain but also as a means to assess the distribution of authors, countries/regions, and journals associated with a specific research field. Therefore, bibliometric analysis lays the foundation for future research directions and development[18]. In this study, a scientific knowledge map of stem cell research within the realm of DF was constructed using CiteSpace, VOSviewer, and R (4.3.1). This approach was employed to examine the hotspots and development trends within this field.
MATERIALS AND METHODS
Publication sources and search methods
For this study, the Web of Science Core Collection (WoSCC) database was selected as the publication source. This database is widely used within the academic community and encompasses a range of internationally renowned scientific journals of significant impact and exceptional quality. It provides a comprehensive and standardized dataset for bibliometric analysis[19]. Due to the dynamic nature of the database, the literature search was performed on 1 d (August 1, 2023) to mitigate potential biases arising from rapid updates. The search strategy for this study is presented in Table 1. The publication types included articles and reviews, and the language limitation was set to English.
Topic: (TS=("Stem Cells" OR "Cell, Stem" OR "Cells, Stem" OR "Stem Cell" OR "Progenitor Cells" OR "Cell, Progenitor" OR "Cells, Progenitor" OR "Progenitor Cell" OR "Mother Cells" OR "Cell, Mother" OR "Cells, Mother" OR "Mother Cell" OR "Colony-Forming Unit" OR "Colony Forming Unit" OR "Colony-Forming Units" OR "Colony Forming Units")) AND TS=(“Foot, Diabetic" OR "Diabetic Feet" OR "Feet, Diabetic" OR "Foot Ulcer, Diabetic" OR "Diabetic Foot")
2
547
Types of publications: (ARTICLES OR REVIEWS)
3
543
Languages of publications: (ENGLISH)
Publication screening and access
Two researchers (SHS and YX) independently screened the publications for inclusion in this study. The collected literature was exported in two formats: Complete records and references. They were saved as plain text files under the label “download_txt.” The file content included the title, abstract, author information, affiliations, keywords, publication date, and cited references.
Data analysis
All pertinent documents retrieved from the WoSCC database were imported into bibliometrix (based on R 4.3.1.), VOSviewer, and CiteSpace for visualization analysis. Two essential metrics commonly employed to evaluate research performance are the number of publications (Np), which serves as a gauge of productivity, and the number of citations (Nc), which serves as an indicator of impact.
R-bibliometrix is used to conduct bibliometric analysis on leading research nations, institutions, and journals[20]. The primary application of the h-index is to assess researchers’ academic contributions and anticipate their forthcoming scientific accomplishments. The g-index, which is derived from the h-index, can further measure the impact and scholarly achievements of researchers[21]. Moreover, these indices can be obtained to characterize the publication output of a country or region as well as the output of an institution or journal[19,22].
VOSviewer is a network analysis software for scientometric research that was developed by the Centre for Science and Technology Studies at Leiden University in the Netherlands. It provides visual analysis and allows the creation of maps based on network data. The software enables connections between items through cocitation links, co-occurrence, citations, and bibliographic coupling. VOSviewer offers three types of visual maps: Network; overlay; and density visualization[23,24].
The CiteSpace software is a citation visualization and analysis tool rooted in scientometrics and data visualization. It was created by Professor Chaomei Chen at Drexel University using the Java programming language[25]. By leveraging data mining, information analysis, and map visualization techniques, it effectively illustrates the architecture, patterns, and dissemination of scientific knowledge[26].
RESULTS
An overview of stem cells in DF publications
After retrieving and filtering publications from the WoSCC database, a total of 543 publications were included. Among them, 350 articles and 193 reviews were ultimately included in this analysis. The studies were published between 2000 and 2023, and the h-index was 71.
Figure 1 illustrates the geographic distribution of the overall research paper count across all countries and regions. Among the 543 articles, the top two countries accounted for more than half of the total. The United States had the highest number of published papers, followed by China, Iran, England, and Italy.
Figure 1 Geographical distribution of publications on stem cells in diabetic foot research.
Between 2000 and 2022, the annual Np increased rapidly and exhibited a polynomial fit, y = 0.1484x2 - 593.9x + 594231, R2 = 0.9714. The annual cumulative publication volume followed an exponential curve, y = 2E-247e0.2843x, R2 = 0.9601 (Figure 2).
Figure 2 Publication count divided by year over the past 23 years.
Np: Number of publications.
Country/region contributions to global publications
The top 10 countries/regions in terms of output are shown in Table 2. The country with the highest number of published papers was the United States (183/543, 33.70%), followed by China (152/543, 27.99%), Iran (35/543, 6.45%), England (33/543, 6.08%), and Italy (28/543, 5.16%). Papers from the United States were cited 9663 times, accounting for 44.84% of the total citations, followed by China (3828; 17.76%) and England (2449; 11.36%). In addition, the United States (46) had the highest h-index, followed by China (32) and England (20). The network (Figure 3A) and density (Figure 3B) maps constructed using VOSviewer also indicated the research influence of the United States and China. As shown in Figure 3C, the largest connected component in the co-occurrence network of countries/regions consisted of 60 nodes and 185 connections (density = 0.01). The purple hue corresponds to the betweenness centrality coefficients of countries/regions, encompassing the United States (0.83), England (0.23), Italy (0.17), and China (0.15). This indicates that these countries/regions assume a ”bridging” role within this domain, and this finding was also confirmed by the multiple-country publication value in Figure 3D.
Figure 3 Contributions of different countries to research on stem cells in the diabetic foot field.
A: Network visualization of country collaboration; B: Density map of cooperation between countries; C: A network diagram showing international collaborations, with purple circles representing intermediation centrality; D: Top 20 countries for corresponding authors. MCP: Multiple-country publications; SCP: Single-country publications.
Table 2 Top 10 countries/regions with the highest research productivity.
No.
Country
Np
Np, %
h-index
Nc
Nc, %
Centrality
1
United States
183
33.70
46
9663
44.84
0.83
2
China
152
27.99
32
3828
17.76
0.15
3
Iran
35
6.45
16
901
4.18
0.03
4
England
33
6.08
20
2449
11.36
0.23
5
Italy
28
5.16
14
721
3.35
0.17
6
India
25
4.60
11
1249
5.80
0.02
7
Germany
24
4.42
13
766
3.55
0.05
8
South Korea
16
2.95
11
953
4.42
0.06
9
Spain
16
2.95
8
362
1.68
0.02
10
Ireland
13
2.39
8
981
4.55
0.09
Analysis of author institution publications
We compiled a list of the 10 institutions with the highest Np (Table 3). These institutions were located in the United States (5/10), China (4/10), and Iran (1/10). The top six institutions in terms of publication ranking included Shahid Beheshti University Medical Sciences (Iran, 13/2.39%), University of Louisville (the United States, 12/2.21%), Army Medical University (China, 12/2.21%), Tongji University (China, 11/2.03%), Chinese Academy of Medical Sciences-Peking Union Medical College (China, 11/2.03%), and Boston University (density = 0.01). Boston University (0.13) and the University of California System (0.13) had the highest centrality, and their nodes were identified by purple circles (Figure 4).
Chinese Academy of Medical Sciences-Peking Union Medical College
China
11
2.03
6
272
0.01
0.04
6
Boston University
United States
11
2.03
9
813
0.04
0.13
7
University of California System
United States
10
1.84
10
386
0.02
0.13
8
Harvard University
United States
10
1.84
12
909
0.04
0.06
9
University of Miami
United States
9
1.66
8
859
0.04
0
10
Shanghai Jiao Tong University
China
7
1.29
4
191
0.01
0.06
Author analysis and cocitation author analysis.
In 1997, economists Katz and Martin provided a definition for “scientific collaboration,” wherein scholars unite to collaboratively pursue shared scientific objectives[27]. We identified 2798 authors who have published articles on the topic of stem cells in DF research. Figure 5A displays the 10 authors with the highest average annual publication count. Among them, Bayat[28], Amini[29], and Tomic-Canic[30] published the highest number of studies (n = 12), followed by Veves (n = 6)[31] and Pastar C (n = 4)[32] (Table 4). Cocitation authors refer to the authors who are cited together in the same article. Figure 5B and C show the network and density maps of cocited authors, respectively. Among the 28753 cocited authors, 173 have been cited together more than 20 times. The top five cocited authors were FALANGA V (n = 151), BREM H (n = 87), ARMSTRONG DG (n = 86), BOULTON AJM (n = 70), and MARSTON WA (n = 59) (Table 4). As shown in Figure 5D, the author with the highest betweenness centrality in terms of citations was FALANGA V (0.36), followed by ARMSTRONG DG (0.21) and BOULTON AJM (0.12).
Figure 5 Contributions of different authors to research on stem cells in the diabetic foot field.
A: Top 10 authors in terms of average publication count per year; B: Network visualization of country collaboration; C: Density map of cooperation between countries; D: Network diagram showing international collaborations, with purple circles representing intermediation centrality.
Table 4 Top 5 authors and cocited authors with the most publications.
Studies related to the use of stem cell therapy in DF patients were published in a total of 280 different journals. The journal Stem Cell Research & Therapy [22/7.86%, impact factor (IF): 7.5, Journal Citation Reports (JCR): Q1] had the highest output quantity; this journal emphasizes basic, clinical, and translational research on stem cell therapy and regenerative medicine. The next most productive journal was International Wound Journal (17/6.07%, IF: 3.1, JCR: Q2). Among the top 10 journals, 8 belonged to the JCR Q1 category, with 9 having an IF exceeding 3 (Table 5). Additionally, Stem Cell Research & Therapy had the highest h-index (Figure 6A) and g-index (Figure 6B).
Figure 6 Contributions of different authors to research on stem cells in the diabetic foot field.
A: Top 10 journals in terms of h-index; B: Top 10 journals in terms of g-index; C: CiteSpace visualization of cocited journals; D: Biplot overlay of journals on stem cells in the diabetic foot field (left side represents areas covered by citing journals, and the right side represents areas covered by cited journals).
Table 5 Top 10 journals and cocited journals with the most publications.
No.
Journal
Np
IF in 2020
JCR
Cocited journal
Cocitation, %
IF in 2020
JCR
1
Stem Cell Research & Therapy
22
7.5
Q1
Wound Repair and Regeneration
1297 (27.79)
2.9
Q1
2
International Wound Journal
17
3.1
Q2
Diabetes Care
951 (20.38)
16.2
Q1
3
Wound Repair and Regeneration
14
2.9
Q1
Biomaterials
681 (14.59)
14.0
Q1
4
Advances in Wound Care
11
4.9
Q1
Journal of Investigative Dermatology
668 (14.31)
6.5
Q1
5
Diabetes-Metabolism Research and Reviews
9
8.0
Q2
PLOS One
626 (13.41)
3.7
Q2
6
International Journal of Molecular Sciences
9
5.6
Q1
Plastic and Reconstructive Surgery
576 (12.34)
3.6
Q1
7
Frontiers in Endocrinology
8
5.2
Q1
International Wound Journal
575 (12.32)
3.1
Q2
8
Biomedicines
8
4.7
Q1
Stem Cell Research & Therapy
488 (10.46)
7.5
Q1
9
Plastic and Reconstructive Surgery
8
3.6
Q1
Stem Cells
462 (9.90)
5.2
Q1
10
Diabetes
7
7.7
Q1
Advances in Wound Care
457 (9.79)
4.9
Q1
Among the 4667 cocited journals, 82 journals have been cited more than 100 times. Table 2 shows that Wound Repair and Regeneration (1297/27.79%, IF: 2.9, JCR: Q1) had the highest number of citations, followed by Diabetes Care (951/20.38%, IF: 16.2, JCR: Q1) and Biomaterials (681/14.59%, IF: 14, JCR: Q1). Among the top 10 cocited journals, 8 were in JCR Q1, and they all had an IF exceeding 3 (Table 5 and Figure 6C).
The dual plot of the journals displays the distribution of relationships between them. As shown in Figure 6D, there are primarily four citation pathways, consisting of two orange paths and two green paths. The relevant pathways are listed in Table 6.
Table 6 Paths between citing journals and cited journals.
No.
Journal
Cited journal
Path color
1
Molecular/Biology/Immunology
Molecular/Biology/Genetics
Orange
2
Molecular/Biology/Immunology
Health/Nursing/Medicine
Orange
3
Medicine/Medical/Clinical
Molecular/Biology/Genetics
Green
4
Medicine/Medical/Clinical
Health/Nursing/Medicine
Green
Cocited reference analysis
Cocitation describes how often two documents are referenced jointly[33]. Table 7 lists the top 10 referenced articles that were most commonly cocited. Among the 28717 cited articles, 27 articles have been cited more than 30 times. The top six referenced articles have all been cited more than 50 times. The article by Armstrong et al[34] that was published in the New England Journal of Medicine in 2017 had the highest number of cocitations, followed by the article published by Lopes et al[35] in 2018 (Figure 7A). Based on cluster analysis, a total of eight clusters were identified (Figure 7B), indicating the reliability of the clustering results. These clusters primarily included #0 “diabetic foot,” #1 “skin defect,” #2 “low-level laser therapy,” #3 “adipose-derived stem cell therapy for local chronic radiation injury,” #4 “occlusive dressing,” and #5 “exosomes.” In addition, research hotspots can be reflected in the timeline of cocited references. Relatively speaking, cluster #0 “diabetic foot” and cluster #5 “exosomes” were recent hotspots. Furthermore, analysis of citation bursts can accurately identify articles that have garnered significant attention within a particular field. This method can help filter out articles that are likely to have a major impact on future research. The initial instance of a powerful citation burst emerged in 2004[36], whereas the latest occurrence of a significant citation burst appeared in 2020[37]. Additionally, the study published by Maxson et al[38] in 2012 exhibited the strongest citation burst intensity (10.19)[39] (Figure 7C).
Figure 7 Analysis of cocited references.
A: Visualization of cocited references. Nodes represent cocited references, with red circles representing citation bursts references; B: Timeline graph of cluster analysis; C: Top 17 references with the strongest citation bursts.
Table 7 Top 10 cocited references referring to cocitations.
A total of 2380 keywords were derived from the included studies. After excluding keywords that appeared fewer than five times and merging equivalent keywords, a total of 219 keywords were identified. We have displayed the top 20 keywords (Table 8) and built a related network (Figure 8A) and density graphs (Figure 8B). The top five keywords were “diabetic foot ulcers” (253), “wound healing” (130), “mesenchymal stem cells” (98), “stem cells” (78), and “angiogenesis” (75). Figure 8 displays the keyword timeline, illustrating the timeline of keywords in the clusters based on their appearance dates. The color of the keywords matches the cluster label color (Figure 8C). A total of eight clusters were identified: #0 “diabetes mellitus;” #1 ”expression;” #2 “chronic wounds;” #3 “adipose-derived stem cells;” #4 “diabetic foot;” #5 “diabetic wound healing;” #6 “double-blind;” and #7 “biological therapies.” Additionally, Figure 8D displays the top 10 keywords with the highest citation bursts. “Repair” (5.15) had the highest burst strength, followed by “skin” (4.15) and “venous leg ulcers” (3.93). “Endothelial progenitor cells” (2006-2014) and “venous leg ulcers” (2015-2019) have shown prolonged citation bursts, indicating that research in these areas has been attracting an increasing amount of attention from researchers.
Figure 8 Analysis of keywords.
A: Co-occurrence and clustering of keywords; B: Density map of keywords co-occurrence; C: Top 8 cluster timeline distributions; D: Top 17 cocited references with the most citation burstiness.
Stem cell therapy has recently emerged as a novel approach for DF management, as it has exhibited safety and efficacy across preclinical and clinical trials[35]. This study is the first bibliometric analysis on global research related to the use of stem cell therapy for DF. These findings can provide researchers with a systematic and intuitive overview of the overall trends in this field[40,41].
General information
Based on the information retrieved from the WoSCC database as of August 1, 2023, there have been a total of 982 studies related to stem cell therapy and DF published across 280 academic journals. These studies involve a total of 2798 authors affiliated with 543 institutions across 60 countries/regions. The yearly fluctuations in Np serve as a significant gauge for discerning development trends within this domain[42,43]. The publication trends from 2000 to 2003 indicate a lack of research during this period, suggesting a limited depth of study on stem cell therapy in DF. The year 2004 was a turning point for this topic[44], as an increasing number of researchers started focusing on the role of stem cell therapy in the treatment of DF. At that time, the number of relevant publications began to show a rapid upward trend.
Through visual analysis of national and institutional distribution, we can see that the United States and China are the leading countries in the research and development of stem cell therapy for DF. Among the top 10 institutions researching this topic, the majority (90%) are located in the United States and China, including the University of Louisville, Army Medical University, and Tongji University. Within the 10 highest-ranked nations, the United States (0.83) demonstrated the strongest centrality and maintained the highest multiple-country publication value, signifying its substantial impact within this area. Other countries, such as China (0.15), England (0.23), and Italy (0.17), also had centrality values exceeding 0.1, suggesting their involvement in international exchanges and collaborations to a certain extent.
Identifying the core authors in this field can help researchers find potential collaborators[45]. Professor Bayat, from Shahid Beheshti University of Medical Sciences in Iran, was the author with the highest number of published papers. He has conducted a series of studies on the mechanisms and therapeutic effects of photobiomodulation in stem cell therapy for DF[46,47]. His research has shown that subjecting diabetic adipose-derived stem cells to photobiomodulation prior to treatment markedly expedites the process of wound healing[48]. Among the cited authors, Vincent Falanga from Boston University School of Medicine has been referenced 151 times and had the largest node in this field. He has conducted several high-quality reviews on the use of stem cells for the treatment of chronic wounds[49,50].
The analysis of the distribution of academic journals helps to identify the core journals in specific research fields[51]. Multiple studies on the use of stem cells in DF have been published in influential journals such as Stem Cell Research & Therapy and the International Wound Journal. Among the top 10 journals, 8 are classified as JCR Q1, which indicates that the research quality of articles in the field is high. From the perspective of commonly cited academic journals, we can see that most of the research comes from highly influential journals in the field of stem cells or wound repair. The journal dual overlay represents the thematic distribution of academic journals, with four citation paths. This implies that current research related to stem cells and DF is focused not only on basic research but also on translational medical research.
Intellectual base
Analysis of cocited references can provide in-depth insights into the core themes and major discoveries of current research[52]. The primary emphasis of the top 10 most cocited references revolves around the pathological and physiological mechanisms, treatment approaches, and everyday handling of stem cells in the context of DF. The results of citation analysis revealed that the article written by Armstrong et al[34] published in the New England Journal of Medicine in 2017 had the highest frequency of cocitations. This article described the epidemiology and health management of recurrent DFUs and emphasized that the focus of work should be on prevention. Another study published by Lopes et al[35] in 2018, which has a citation count of 32, proposed that stem cell therapy was an effective method for treating DFUs. This suggested that for some patients who do not have other options for vascular reconstruction, stem cell therapy can be considered an alternative to amputation. The most explosive reference was the paper published by Maxson et al[38] in Stem Cells Translational Medicine. This article delineated the function of mesenchymal stem cells (MSCs) in the process of wound healing and elucidated their ability to attract additional host cells and release growth factors and matrix proteins to orchestrate the mending mechanism.
In the clustering analysis of cocited references, there were modules related to occlusive dressing, low-level laser, and exosomes, among others. With the use of advanced techniques, there have been some breakthroughs in the research on stem cells in the field of DF science. Exosomes derived from MSCs carry forward the robust functions of their originating cells. These functions include tasks such as managing inflammation and immune responses, fostering angiogenesis, facilitating cell proliferation and movement, mitigating oxidative stress, and regulating the equilibrium of collagen remodeling[53]. They can potentially avoid the potential risks associated with direct stem cell transplantation. Stem cell-derived exosomes may be a future research trend.
In chronic wounds, stem cell survival without scaffold support is short-lived. Multifunctional hydrogel wound dressings play a crucial role in the healing of skin wounds, as they can sustain stem cell viability for an extended period, provide moisture, and prevent electrolyte and fluid loss in DFUs[54]. Furthermore, photobiomodulation may also play an important role in stem cell applications. The combination of stem cells and photobiomodulation has shown the potential to accelerate the healing process of diabetic wounds[47].
Hotspots and frontiers
Keywords summarize the research topics and core content. Based on keyword co-occurrence analysis, it is possible to understand the distribution and development of various research hotspots in a specific field[55]. The keyword clustering ultimately identified eight possible research directions, including “diabetes mellitus,” “expression,” “chronic wounds,” “adipose-derived stem cells,” “diabetic foot,” “diabetic wound healing,” “double-blind,” and “biological therapies.” The most common keywords were “diabetic foot ulcers,” “wound healing,” “mesenchymal stem cells,” “stem cells,” and “angiogenesis.” In addition, the most frequently mentioned keywords, included “repair,” “skin,” “venous leg ulcers,” “efficacy,” and “mechanisms.” The aforementioned words indicate that the use of stem cells in DF has not only been examined in basic research studies but has also been investigated in clinical translation studies.
A growing body of research indicates that MSCs are capable of enhancing angiogenesis and epithelial remodeling, engaging in immune regulation, mitigating inflammation, and ultimately contributing to the facilitation of DFU repair. They have become an effective therapeutic approach for treating DF[56]. It is worth noting that controlled studies conducted using animal models indicated that combining stem cells with biostimulants (such as photobiomodulation) can reduce biofilm formation and expedite the healing of infected diabetic wounds[57]. Multiple randomized controlled trials have confirmed that stem cell therapy is a promising treatment for DF, as it can improve healing rates and reduce the amputation rate[58]. There is good clinical evidence promoting the clinical application and translation of stem cell therapy for DF. When selecting clinical stem cell types, considerations should be given to the availability and supply of stem cells, such as ease of acquisition, good manufacturing practices, and broad in vitro proliferative capacity[59]. Because of their convenient procurement, uncomplicated extraction methods, and documented safety profile, adipose-derived stem cells and other stem cell variants have become increasingly popular. Consequently, they have emerged as pivotal areas of concentration within research endeavors[60]. Beyond their regenerative characteristics and capacity to stimulate blood vessel development, stem cells sourced from adipose tissue exhibit a greater content when contrasted with bone marrow aspirate-derived stem cells[59].
Through the utilization of bibliometric analysis, this study systematically presented the body of research concerning stem cell therapy in DF cases while also identifying focal points and burgeoning trends within this domain. Therefore, we have also depicted the potential mechanism diagram of stem cell research in the field of DF in Figure 9. Nevertheless, there are certain limitations associated with this study. First and foremost, the study’s scope was confined to the WoSCC database for literature screening, potentially resulting in the omission of pertinent articles. This is due to the limitations of current bibliometric software, which makes it difficult to analyze multiple databases simultaneously. Additionally, this study utilized only a few tools, such as VOSviewer, CiteSpace, and R bibliometrics package, which may not fully explain the data. In future research, we intend to explore the use of other tools, such as artificial neural networks, to further analyze and interpret the data.
The bibliometric analysis indicated that research on stem cell therapy in DF has been rapidly progressing and holds great prospects for the future. The United States and China are scientific hubs for the research of stem cells in DF. In this field, Iran’s Shahid Beheshti University Medical Sciences demonstrated the highest productivity, with Dr. Bayat from the same university being an outstanding researcher in this domain. The priority topics revolved around dressings, extracellular vesicles, wound healing, and adipose stem cells. The results of these analyses will help researchers understand the current research status and provide hopeful directions for future studies. Future research will also focus on the clinical translation of stem cell therapies for DF.
ARTICLE HIGHLIGHTS
Research background
Stem cell therapy has shown great potential for treating diabetic foot (DF).
Research motivation
There is currently a lack of comprehensive research in this field.
Research objectives
The purpose of this study was to conduct a bibliometric analysis of studies on the use of stem cell therapy for DF over the past two decades, with the aim of depicting the current global research landscape, identifying the most influential research hotspots, and providing insights for future research directions.
Research methods
We searched the Web of Science Core Collection database for all relevant studies on the use of stem cell therapy in DF. Bibliometric analysis was carried out using CiteSpace, VOSviewer, and R (4.3.1) to identify the most notable studies.
Research results
A search was conducted to identify publications related to the use of stem cells for DF treatment. A total of 542 articles published from 2000 to 2023 were identified. The United States had published the most papers on this subject. In this field, Iran’s Shahid Beheshti University Medical Sciences demonstrated the highest productivity. Furthermore, Dr. Bayat from the same university has been an outstanding researcher in this field. Stem Cell Research & Therapy was the journal with the highest number of publications in this field. The main keywords were “diabetic foot ulcers,” “wound healing,” and “angiogenesis.”
Research conclusions
This study systematically illustrated the advances in the use of stem cell therapy to treat DF over the past 23 years. Current research findings suggested that the hotspots in this field included stem cell dressings, exosomes, wound healing, and adipose-derived stem cells.
Research perspectives
Future research should also focus on the clinical translation of stem cell therapies for DF.
Footnotes
Provenance and peer review: Unsolicited article; Externally peer reviewed.
Gallego-Selles A, Martin-Rincon M, Martinez-Canton M, Perez-Valera M, Martín-Rodríguez S, Gelabert-Rebato M, Santana A, Morales-Alamo D, Dorado C, Calbet JAL. Regulation of Nrf2/Keap1 signalling in human skeletal muscle during exercise to exhaustion in normoxia, severe acute hypoxia and post-exercise ischaemia: Influence of metabolite accumulation and oxygenation.Redox Biol. 2020;36:101627.
[PubMed] [DOI][Cited in This Article: ][Cited by in Crossref: 17][Cited by in F6Publishing: 35][Article Influence: 8.8][Reference Citation Analysis (0)]
Chen P, Carville K, Swanson T, Lazzarini PA, Charles J, Cheney J, Prentice J; Australian Diabetes-related Foot Disease Guidelines & Pathways Project. Australian guideline on wound healing interventions to enhance healing of foot ulcers: part of the 2021 Australian evidence-based guidelines for diabetes-related foot disease.J Foot Ankle Res. 2022;15:40.
[PubMed] [DOI][Cited in This Article: ][Cited by in Crossref: 12][Cited by in F6Publishing: 14][Article Influence: 7.0][Reference Citation Analysis (0)]
Zhou XC, Huang YB, Liu Z, Wu HJ, Huang HZ, Tian Y, Hong SW, Hu HJ, Lv LJ, Lv ZZ. Bibliometric Analysis of Functional Magnetic Resonance Imaging Studies on Manual Therapy Analgesia from 2002-2022.J Pain Res. 2023;16:2115-2129.
[PubMed] [DOI][Cited in This Article: ][Cited by in F6Publishing: 4][Reference Citation Analysis (0)]
Synnestvedt MB, Chen C, Holmes JH. CiteSpace II: visualization and knowledge discovery in bibliographic databases.AMIA Annu Symp Proc. 2005;2005:724-728.
[PubMed] [DOI][Cited in This Article: ]
Bayat M, Albright R, Hamblin MR, Chien S. Impact of Blue Light Therapy on Wound Healing in Preclinical and Clinical Subjects: A Systematic Review.J Lasers Med Sci. 2022;13:e69.
[PubMed] [DOI][Cited in This Article: ][Reference Citation Analysis (0)]
Amini A, Ghasemi Moravej F, Mostafavinia A, Ahmadi H, Chien S, Bayat M. Photobiomodulation Therapy Improves Inflammatory Responses by Modifying Stereological Parameters, microRNA-21 and FGF2 Expression.J Lasers Med Sci. 2023;14:e16.
[PubMed] [DOI][Cited in This Article: ][Reference Citation Analysis (0)]
Yamaguchi Y, Yoshida S, Sumikawa Y, Kubo T, Hosokawa K, Ozawa K, Hearing VJ, Yoshikawa K, Itami S. Rapid healing of intractable diabetic foot ulcers with exposed bones following a novel therapy of exposing bone marrow cells and then grafting epidermal sheets.Br J Dermatol. 2004;151:1019-1028.
[PubMed] [DOI][Cited in This Article: ][Cited by in Crossref: 41][Cited by in F6Publishing: 43][Article Influence: 2.3][Reference Citation Analysis (0)]
Amini A, Pouriran R, Abdollahifar MA, Abbaszadeh HA, Ghoreishi SK, Chien S, Bayat M. Stereological and molecular studies on the combined effects of photobiomodulation and human bone marrow mesenchymal stem cell conditioned medium on wound healing in diabetic rats.J Photochem Photobiol B. 2018;182:42-51.
[PubMed] [DOI][Cited in This Article: ][Cited by in Crossref: 30][Cited by in F6Publishing: 36][Article Influence: 6.0][Reference Citation Analysis (0)]
Amini A, Chien S, Bayat M. Effectiveness of preconditioned adipose-derived mesenchymal stem cells with photobiomodulation for the treatment of diabetic foot ulcers: a systematic review.Lasers Med Sci. 2022;37:1415-1425.
[PubMed] [DOI][Cited in This Article: ][Cited by in Crossref: 1][Reference Citation Analysis (0)]
Gould L, Abadir P, Brem H, Carter M, Conner-Kerr T, Davidson J, DiPietro L, Falanga V, Fife C, Gardner S, Grice E, Harmon J, Hazzard WR, High KP, Houghton P, Jacobson N, Kirsner RS, Kovacs EJ, Margolis D, McFarland Horne F, Reed MJ, Sullivan DH, Thom S, Tomic-Canic M, Walston J, Whitney J, Williams J, Zieman S, Schmader K. Chronic wound repair and healing in older adults: current status and future research.Wound Repair Regen. 2015;23:1-13.
[PubMed] [DOI][Cited in This Article: ][Cited by in Crossref: 105][Cited by in F6Publishing: 131][Article Influence: 14.6][Reference Citation Analysis (0)]
Yang F, Dong Y, Bai C, Alzogool M, Wang Y. Bibliometric and visualized analysis of myopic corneal refractive surgery research: from 1979 to 2022.Front Med (Lausanne). 2023;10:1141438.
[PubMed] [DOI][Cited in This Article: ][Reference Citation Analysis (0)]
Chen X, Wu J, Cao X, Jiang H, Wu Z, Zeng Z, Chen H, Zhang J. The role of gel wound dressings loaded with stem cells in the treatment of diabetic foot ulcers.Am J Transl Res. 2021;13:13261-13272.
[PubMed] [DOI][Cited in This Article: ]
Elsharkawi M, Ghoneim B, O'Sullivan M, Lowery AJ, Westby D, Tawfick W, Walsh SR. Role of Adipose Derived Stem Cells in Patients with Diabetic Foot Ulcers: Systematic Review and Meta-Analysis of Randomised Controlled Trials.Int J Low Extrem Wounds. 2023;15347346231174554.
[PubMed] [DOI][Cited in This Article: ][Cited by in F6Publishing: 3][Reference Citation Analysis (0)]