Ginsenoside Rg1 and platelet-rich fibrin enhance human breast adipose-derived stem cell function for soft tissue regeneration

Platelet Power: Revitalizing Endodontics With Scaffolds

This article provides an overview of a biologically based method for restoring damaged tooth structures and pulp tissues known as regenerative endodontics. It explores the concept of regenerative endodontics, its tissue engineering approach, and its application in maintaining vitality. The article discusses the significance of the factors affecting growth, scaffolds, and stem cells being the three tissue engineering components involved in the regeneration of pulp tissues. It also delves into the classification of scaffolds and the role of platelet-rich fibrin (PRF) and platelet-rich plasma (PRP) as biological scaffolds. The methodology section details the search process for relevant studies, and the review section presents research findings associated with PRF and its application in regeneration and repair of tissue. The article concludes by highlighting the potential of advanced PRF and injectable PRF in regenerative endodontics, with a focus on their impact on tissue regeneration and healing.

Liquid platelet-rich fibrin produced via horizontal centrifugation decreases the inflammatory response and promotes chondrocyte regeneration in vitro

Objective: Recently, liquid platelet-rich fibrin (PRF), a rich source of concentrated platelets and growth factors, has emerged as a promising agent for stimulating tissue regeneration. However, its specific efficacy in chondrocyte proliferation and cartilage regeneration remains underexplored. To address this question, we investigated liquid PRF obtained through horizontal centrifugation and compared its effects with hyaluronic acid (HA), a high molecular weight glucosamine supplement widely used in clinical practice to safeguard against chondral damage. Materials and Methods: Liquid PRF, produced using horizontal centrifugation (liquid H-PRF) at 500 g for 8 min, served as our experimental agent. We conducted cell viability and proliferation assays using PRF-conditioned medium. We assessed the chondrocyte phenotype of ATDC5 cells through toluidine blue and alcian blue staining, real-time polymerase chain reaction (RT-PCR), Western blotting, and immunofluorescence staining. Furthermore, we examined the expression of genes involved in inflammation through RT-PCR and Western blot analysis. Results: Liquid H-PRF exerted notable effects on chondrocytes, influencing proliferation, inflammatory responses, and chondrogenic differentiation. The H-PRF group displayed significantly higher expression of chondrogenic markers, including Col2a1, compared to HA-treated cells, whereas aggrecan expression was significantly higher in the HA group. PRF also demonstrated the ability to reduce inflammatory levels in chondrogenic ATDC5 cells, and this effect was further enhanced when PRF from the buffy coat zone was added. In comparison, chondrocytes cultured in the HA group produced significantly fewer inflammatory factors than those in the PRF group, as confirmed qualitatively by Western blot analysis. Conclusion: Liquid H-PRF emerged as a potent stimulator for chondrogenesis and a regulator of the inflammatory response, achieving levels similar to HA. Moreover, liquid H-PRF exhibited strong potential for enhancing the production of cartilage extracellular matrix and promoting chondrogenic regeneration with notably increased Col2a1 levels. Future research should encompass animal studies and human trials to further evaluate the comparative effectiveness of liquid PRF versus HA, potentially as an alternative or complementary strategy for future clinical applications.

Ginsenosides on stem cells fate specification-a novel perspective

Recent studies have demonstrated that stem cells have attracted much attention due to their special abilities of proliferation, differentiation and self-renewal, and are of great significance in regenerative medicine and anti-aging research. Hence, finding natural medicines that intervene the fate specification of stem cells has become a priority. Ginsenosides, the key components of natural botanical ginseng, have been extensively studied for versatile effects, such as regulating stem cells function and resisting aging. This review aims to summarize recent progression regarding the impact of ginsenosides on the behavior of adult stem cells, particularly from the perspective of proliferation, differentiation and self-renewal.

Advanced-platelet-rich fibrin extract promotes adipogenic and osteogenic differentiation of human adipose-derived stem cells in a dose-dependent manner in vitro

Advanced platelet-rich fibrin (A-PRF) is an autogenous biological material obtained from peripheral blood. A-PRF extract (A-PRFe) contains a high concentration of various cytokines that are increasingly appreciated for their roles in improving stem cell repairing function during tissue regeneration. However, the optimal A-PRFe concentration to stimulate stem cells is unknown. This study aimed to identify the optimal concentrations of A-PRFe to promote adipogenic and osteogenic differentiation of human adipose-derived stem cells (ASCs). We produced A-PRFe from A-PRF clots by centrifuging fresh peripheral blood samples and isolated and identified ASCs using surface CD markers and multilineage differentiation potential. Enzyme-linked immunosorbent assay (ELISA) showed the concentrations of several cytokines, including b-FGF, PDGF-BB, and others, increased gradually, peaked on day 7 and then decreased. Cell proliferation assays showed A-PRFe significantly stimulated ASC proliferation, and proliferation significantly increased at higher A-PRFe doses. The degree of adipogenic and osteogenic differentiation increased at higher A-PRFe concentrations in the culture medium, as determined by oil red O and alizarin red staining. Reverse transcription polymerase chain reaction (RT-PCR) showed that expression levels of genes related to adipogenic/osteogenic differentiation (PPARγ2, C/EBPα, FABP4, Adiponectin, and ALP, OPN, OCN, RUNX2), paracrine (HIF-1α, VEGF, IGF-2) and immunoregulation (HSP70, IL-8) function were higher in groups with a higher concentration of A-PRFe than in lower concentration groups. This study demonstrates that A-PRFe is ideal for use in ASC applications in regenerative medicine because it improves biological functions, including proliferation, adipogenic/osteogenic differentiation, and paracrine function in a dose-dependent manner.

Novel applications of platelet concentrates in tissue regeneration (Review)

Numerous studies have explored the suitability of biocompatible materials in regenerative medicine. Platelet concentrates are derived from centrifuged blood and are named according to their biological characteristics, such as platelet-rich plasma, platelet-rich fibrin and concentrated growth factor. Platelet concentrates have gained considerable attention in soft and hard tissue engineering. Indeed, multiple components of autologous platelet concentrates, such as growth factors, fibrin matrix and platelets, serve essential roles in wound healing. Current studies are focused on cutting-edge strategies to meet the requirements for tissue restoration by improving the properties of autologous platelet concentrates. In the present review, applications of platelet concentrates for tissue engineering are discussed, presenting a selection of recent advances and novel protocols. In addition, several aspects of these strategies, such as the advantages of lyophilized platelet concentrates and the combination of platelet concentrates with biomaterials, stem cells or drugs are discussed. The present review aims to summarize novel strategies using platelet concentrates to improve the outcomes of wound healing.

Ginsenoside RG1 enhances the paracrine effects of bone marrow-derived mesenchymal stem cells on radiation induced intestinal injury

Content and aims: Ginsenoside RG1 (RG1) is thought to enhance proliferation and differentiation of stem cell, however, its role on paracrine efficacy of stem cell remains unclear. Here we examined if and how RG1 enhances the paracrine effects of bone marrow-derived mesenchymal stem cells (BM-MSCs) on radiation induced intestinal injury (RIII).

METHOD

Irradiated rats randomly received intraperitoneal injection of conditioned medium (CM) derived from non-activated BM-MSCs (MSC-CM) or BM-MSCs pre-activated by RG-1 (RG1-MSC-CM). Intestinal samples were collected, followed by the evaluation of histological and functional change, apoptosis, proliferation, inflammation, angiogenesis and stem cell regeneration. The effects of heme oxygenase-1 (HO-1) were investigated using HO-1 inhibitor or siRNA.

RESULT

RG1 enhanced the paracrine efficacy of BM-MSCs partially through upregulation of HO-1. RG1-MSC-CM rather than MSC-CM significantly improved the survival and intestinal damage of irradiated rats via improvement of intestinal proliferation/apoptosis, inflammation, angiogenesis and stem cell regeneration in a HO-1 dependent mechanism. The mechanism for the superior paracrine efficacy of RG1-MSC-CM is related to a higher release of two pivotal cytokines VEGF and IL-6.

CONCLUSION

Our study revealed that RG1 enhances paracrine effects of BM-MSCs on RIII, providing a novel method for maximizing the paracrine potential of MSCs.

The development of laminin-alginate microspheres encapsulated with Ginsenoside Rg1 and ADSCs for breast reconstruction after lumpectomy

Many technologies have been developed for breast reconstruction after lumpectomy. Although the technologies achieved promising success in clinical, there are still many shortages hanging over and trouble the researchers. Tissue engineering technology was introduced to plastic surgery that gave a light to lumpectomy patients in breast reconstruction. The unexpected absorption rate, resulting from limited vascularization and low cell survival rate, is a major factor that leads to unsatisfactory results for the previous studies in our lab. In the study, the laminin-modified alginate synthesized by a new method of low concertation of sodium periodate would be mixed with ADSCs and Rg1 in the medium; and then sprayed into a calcium chloride (CaCl₂) solution to prepare into microsphere (abbreviated as ADSC–G-LAMS) by bio-electrospray with a power syringe for the mass production and smaller bead size. The developed ADSC–G-LAMS microspheres had the diameter of 232 ± 42 μm. Sustained-release of the Rg1 retained its biological activity. WST-1, live/dead staining, and chromosome aberration assay were evaluated to confirm the safety of the microspheres. In in vivo study, ADSC–G-LAMS microspheres combined with autologous adipocytes were transplanted into the dorsum of rats by subcutaneous injection. The efficacy was investigated by H&E and immunofluorescence staining. The results showed that the bioactive ADSC–G-LAMS microspheres could integrate well into the host adipose tissue with an adequate rate of angiogenesis by constantly releasing Rg1 to enhance the ADSC or adipocyte survival rate to join tissue growth and repair with adipogenesis for breast reconstruction after lumpectomy.

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Laminin-modified alginate was successfully synthesized to mimic early embryonic environment.

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Adipose-derived stem cells (ADSCs) and ginsenoside Rg1 were encapsulated into laminin-alginate microspheres (ADSC–G-LAMS) by bio-electrospray method.

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ADSC–G-LAMS microspheres integrated into the host adipose tissue with an adequate rate of angiogenesis by constantly releasing Rg1.

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The developed bioactive ADSC–G-LAMS microspheres can be potential scaffolds for stem cells and angiogenic factor carriers for tissue engineering.

FGF2-induced PI3K/Akt signaling evokes greater proliferation and adipogenic differentiation of human adipose stem cells from breast than from abdomen or thigh

In this study, human adipose stem cells were isolated from subcutaneous fat in the thigh (htASCs), abdomen (haASCs) and breast (hbASCs). Flow cytometry was used to detect cell surface markers, and an enzyme-linked immunosorbent assay was used to detect paracrine activity. Paracrine gene expression in the three cell types was examined using real-time qPCR, and adipogenic ability was assessed using Oil Red O staining. RNA from third-passage haASCs and hbASCs was sequenced. The results showed that the differentiation potential marker markers CD49d and CD54 were similar across hbASCs from 10 subjects. The hbASCs showed higher colony forming ability and expression of fibroblast growth factor-2, tissue inhibitor of metalloproteinase-1 and stromal cell derived factor-1 than htASCs and haASCs. Stimulating hbASCs with FGF2 promoted adipogenic differentiation, while treating the cells with the PI3K inhibitor LY294002 inhibited differentiation. These results suggest that the PI3K/Akt signaling pathway can promote proliferation and adipogenic differentiation of adipose stem cells, and that activation of this pathway by FGF2 may explain why hbASCs show greater proliferation and adipogenic differentiation than haASCs and htASCs.

Ginsenoside Rg1 as an Effective Regulator of Mesenchymal Stem Cells

Recently, breakthroughs have been made in the use of mesenchymal stem cells (MSCs) to treat various diseases. Several stem cell types have been authorized as drugs by the European Medicines Agency and the U.S. Food and Drug Administration. The Chinese official document “Notification of the management of stem cell clinical research (trial)” was also published in August 2015. Currently, China has approved 106 official stem cell clinical research filing agencies and 62 clinical research projects, which are mostly focused on MSC therapy. Hence, the optimization and development of stem cell drugs is imperative. During this process, maximizing MSC expansion, minimizing cell loss during MSC transplantation, improving the homing rate, precisely regulating the differentiation of MSCs, and reducing MSC senescence and apoptosis are major issues in MSC preclinical research. Similar to artemisinin extracted from the stems and leaves of Artemisia annua, ginsenoside Rg1 (Rg1) is purified from the root or stem of ginseng. In the human body, Rg1 regulates organ function, which is inseparable from its regulation of adult stem cells. Rg1 treatment may effectively regulate the proliferation, differentiation, senescence, and apoptosis of MSCs in different microenvironments in vitro or in vivo. In this review, we discuss recent advances in understanding the effect of Rg1 on MSCs and describe the issues that must be addressed and prospects regarding Rg1 regulation of MSCs in preclinical or clinical studies.

Effect of platelet-rich fibrin on cell proliferation, migration, differentiation, inflammation, and osteoclastogenesis: a systematic review of in vitro studies

Objective

To systematically assess the effects of platelet-rich fibrin (PRF) on in vitro cellular behavior.

Methods

A systematic electronic search using MEDLINE database was performed. In vitro studies using PRF were considered and articles published up to June 31, 2018 were screened. Eligible studies were selected based on the use of human PRF.

Results

In total, 1746 titles were identified with the search terms, from these 37 met the inclusion criteria and were chosen for data extraction. In addition, 16 new studies, mainly published in 2019, were also included in the analysis resulting in 53 studies. No meta-analysis could be performed due to the heterogeneity of study designs. Included studies show that PRF enhances proliferation, migration, adhesion, and osteogenic differentiation on a variety of cell types along with cell signaling activation. Furthermore, PRF reduces inflammation, suppresses osteoclastogenesis, and increases the expression of various growth factors in mesenchymal cells.

Summary and conclusions

Despite some notable differences of the studies, the overall findings suggest a positive effect of PRF on cell proliferation, migration, adhesion, differentiation, and inflammation pointing towards a therapeutic potential in regenerative dentistry.

Clinical relevance

PRF serves as a reservoir of bioactive molecules to support wound healing and bone regeneration. Although the cellular mechanisms by which PRF supports the clinical outcomes remain unclear, in vitro research provides possible explanations. This systematic review aims to provide an update of the existing research on how PRF affects basic physiological processes in vitro. The overall findings suggest that PRF induces cell proliferation, migration, adhesion, and differentiation along with possessing anti-inflammatory properties further supporting its therapeutic potential in wound healing and bone regeneration.

The Role of Platelet Concentrates in Facial Fat Grafting

Autologous fat grafting is increasingly being used as a method for the repair of facial soft tissue defects and facial rejuvenation, given its low risk of adverse effects and high efficacy. However, the unpredictability of graft retention is a limitation of this procedure. In addition, there is no standard procedure to date for autologous fat grafting. Different methods have been developed to increase the retention of grafted fat. For instance, platelet concentrates have been used to directly deliver bioactive factors to grafted fat. Platelet concentrates also provide incidental therapeutic benefits by enhancing the persistence of fat grafted in the face via the release of growth factors and cytokines. In this review, we describe current strategies for improving the survival of facial fat grafts, mainly focusing on the application of growth factors/cytokines and platelet concentrates to fat grafting.

Ginsenoside Rg1 Accelerates Paracrine Activity and Adipogenic Differentiation of Human Breast Adipose-Derived Stem Cells in a Dose-Dependent Manner In Vitro

Augmenting the biological function of adipose-derived stromal cells (ASCs) is a promising approach to promoting tissue remodeling in regenerative medicine. Here, we examined the effect of ginsenoside Rg1 on the paracrine activity and adipogenic differentiation capacity of human breast ASCs (hbASCs) in vitro. hbASCs were isolated and characterized in terms of stromal cell surface markers and multipotency. Third-passage hbASCs were cultured in basic media only or basic media containing different concentrations of G-Rg1 (0.1-100 μM). Cell proliferation was assessed by CCK-8 assay. Paracrine activity was assessed using ELISA. Gene expression was measured by qRT-PCR. Adipogenic differentiation capacity was evaluated by Oil red O staining. We found that hbASCs differentiated into adipocytes, osteoblasts, and chondrocytes in appropriate induction culture medium. hbASCs showed expression of CD29, CD44, CD49d, CD73, CD90, CD105, and CD133 but not CD31 and CD45 surface markers. G-Rg1 increased hbASC proliferation and adipogenic differentiation capacity at lower concentrations (0.1-1 μM) and had the opposite effects at higher concentrations (10-100 μM), while enhanced paracrine activity was observed in all experimental groups compared with control group, and the activation effect of lower concentration G-Rg1 was greater than at higher concentration. These results indicate that G-Rg1 can enhance the proliferation, paracrine activity, and adipogenic differentiation capacity of hbASCs within a certain concentration range. Therefore, the use of G-Rg1 may be beneficial to ASC-assisted fat graft regeneration and soft tissue engineering.

Long non-coding RNA HIF1A-AS2 facilitates adipose-derived stem cells (ASCs) osteogenic differentiation through miR-665/IL6 axis via PI3K/Akt signaling pathway

Background

This study was aimed to investigate the role and specific molecular mechanism of HIF1A-AS2/miR-665/IL6 axis in regulating osteogenic differentiation of adipose-derived stem cells (ASCs) via the PI3K/Akt signaling pathway.

Methods

RNAs’ expression profile in normal/osteogenic differentiation-induced ASCs (osteogenic group) was from the Gene Expression Omnibus database. The analysis was carried out using Bioconductor of R. Gene Set Enrichment Analysis and Kyoto Encyclopedia of Genes and Genomes dataset were applied to identify up- and downregulated signaling pathways. Co-expression network of specific lncRNAs and mRNAs was structured by Cytoscape, while binding sites amongst lncRNA, mRNA, and miRNA were predicted by TargetScan and miRanda. ASCs were derived from human adipose tissue and were authenticated by flow cytometry. ASC cell function was surveyed by alizarin red and alkaline phosphatase (ALP) staining. Molecular mechanism of HIF1A-AS2/miR-665/IL6 axis was investigated by RNAi, cell transfection, western blot, and qRT-PCR. RNA target relationships were validated by dual-luciferase assay.

Results

HIF1A-AS2 and IL6 were highly expressed while miR-665 was lowly expressed in induced ASCs. HIF1A-AS2 and IL6 improved the expression level of osteoblast markers Runx2, Osterix, and Osteocalcin and also accelerated the formation of calcium nodule and ALP activity, yet miR-665 had opposite effects. HIF1A-AS2 directly targeted miR-665, whereas miR-665 repressed IL6 expression. Moreover, the HIF1A-AS2/miR-665/IL6 regulating axis activated the PI3K/Akt signaling pathway.

Conclusions

LncRNA HIF1A-AS2 could sponge miR-665 and hence upregulate IL6, activate the PI3K/Akt signaling pathway, and ultimately promote ASC osteogenic differentiation.

Electronic supplementary material

The online version of this article (10.1186/s13287-018-1082-z) contains supplementary material, which is available to authorized users.

CD54+ rabbit adipose-derived stem cells overexpressing HIF-1α facilitate vascularized fat flap regeneration

Fat flap transplantation is frequently performed in patients suffering from soft tissue defects resulting from disease or trauma. This study explored the feasibility of constructing vascularized fat flaps using rabbit adipose-derived stem cells (rASCs) and collagen scaffolds in a rabbit model. We evaluated rASCs proliferation, paracrine function, adipogenesis, vascularization, and CD54 expression, with or without HIF-1α transfection in vitro and in vivo. We observed that adipogenic differentiation potential was greater in rASCs with high CD54 expression (CD54⁺rASCs) than in those with low expression (CD54^–rASCs), both in vitro and in vivo. HIF-1α overexpression not only augmented this effect, but also enhanced cell proliferation and paracrine function in vitro. We also demonstrated that HIF-1α-transfected CD54⁺rASCs showed enhanced paracrine function and adipogenic capacity, and that paracrine function increases expression of angiogenesis-related markers. Thus, CD54⁺rASCs overexpressing HIF-1α enhanced large volume vascularized fat flap regeneration in rabbits, suggesting CD54 may be an ideal candidate marker for ASCs adipogenic differentiation.

Proliferation and differentiation of stem cells in contact with eluate from fibrin-rich plasma membrane

OBJECTIVE

To evaluate the ability of the eluate from fibrin-rich plasma (FRP) membrane to induce proliferation and differentiation of isolated human adipose-derived stem cells (ASCs) into chondrocytes.

METHOD

FRP membranes were obtained by centrifugation of peripheral blood from two healthy donors, cut, and maintained in culture plate wells for 48 h to prepare the fibrin eluate. The SCATh were isolated from adipose tissue by collagenase digestion solution, and expanded in vitro. Cells were expanded and treated with DMEM-F12 culture, a commercial media for chondrogenic differentiation, and eluate from FRP membrane for three days, and labeled with BrdU for quantitative assessment of cell proliferation using the High-Content Operetta® imaging system. For the chondrogenic differentiation assay, the SCATh were grown in micromass for 21 days and stained with toluidine blue and aggrecan for qualitative evaluation by light microscopy. The statistical analysis was performed using ANOVA and Tukey's test.

RESULTS

There was a greater proliferation of cells treated with the eluate from FRP membrane compared to the other two treatments, where the ANOVA test showed significance (p < 0.001). The differentiation into chondrocytes was visualized by the presence of mucopolysaccharide in the matrix of the cells marked in blue toluidine and aggrecan.

CONCLUSIONS

Treatment with eluate from FRP membrane stimulated cell proliferation and induced differentiation of the stem cells into chondrocytes, suggesting a potential application of FRP membranes in hyaline cartilage regeneration therapies.

Metabolic reprogramming by HIF-1 activation enhances survivability of human adipose-derived stem cells in ischaemic microenvironments

OBJECTIVES

Poor cell survival severely limits the beneficial effect of adipose-derived stem cell (ADSC)-based therapy for disease treatment and tissue regeneration, which might be caused by the attenuated level of hypoxia-inducible factor-1 (HIF-1) in these cells after having been cultured in 21% ambient oxygen in vitro for weeks. In this study, we explored the role of pre-incubation in dimethyloxalylglycine (DMOG, HIF-1 activator) in the survivability of human ADSCs in a simulated ischaemic microenvironment in vitro and in vivo. The underlying mechanism and angiogenesis were also studied.

MATERIALS AND METHODS

Survivability of ADSCs was determined in a simulated ischaemic model in vitro and a nude mouse model in vivo. Cell metabolism and angiogenesis were investigated by tube formation assay, flow cytometry, fluorescence staining and real-time polymerase chain reaction (RT-PCR) after DMOG treatment.

RESULTS

The results of the experimental groups showed significant enhancement of ADSC survivability in a simulated ischaemic microenvironment in vitro and transplanted model in vivo. Study of the underlying mechanisms suggested that the improved cell survival was regulated by HIF-1-induced metabolic reprogramming including decreased reactive oxygen species, increased intracellular pH, enhanced glucose uptake and increased glycogen synthesis. Tube formation assay revealed higher angiogenic ability in the DMOG-treated group than that in control group.

CONCLUSIONS

The promotion of HIF-1 level in ADSCs induced by DMOG preconditioning suggests a potential strategy for improving the outcome of cell therapy due to increased survival and angiogenic ability.

MiR-23a targets RUNX2 and suppresses ginsenoside Rg1-induced angiogenesis in endothelial cells

Rg1 is a predominant protopanaxatriol-type of ginsenoside found in Panax ginseng, and it has been shown to have anti-cancer effects in multiple types of cancer cells. However, Rg1 also induces the expression of proangiogenic factors, such as vascular endothelial growth factor (VEGF-A), in endothelial cells. Unfortunately, angiogenesis positively correlates with cancer development. In this study, we identified RUNX2 as a regulator of ginsenoside Rg1-induced angiogenesis for the first time. We found that RUNX2 was directly targeted and regulated by miR-23a. Additionally, miR-23a was shown to inhibit angiogenesis in both human umbilical vein endothelial cells (HUVECs) and in zebrafish. Furthermore, a decrease in RUNX2 expression resulted in translational repression of VEGF-A in HUVECs. Taken together, this study identified a MiR-23a/RUNX2/VEGF-A pathway in angiogenesis and shed light on the molecular mechanism of Rg1-induced angiogenesis. Thus, RUNX2 might be a potential therapeutic target in Rg1-mediated angiogenesis in cancer.

Ubx dynamically regulates Dpp signaling by repressing Dad expression during copper cell regeneration in the adult Drosophila midgut

The gastrointestinal (GI) tract of metazoans is lined by a series of regionally distinct epithelia. To maintain structure and function of the GI tract, regionally diversified differentiation of somatic stem cell (SC) lineages is critical. The adult Drosophila midgut provides an accessible model to study SC regulation and specification in a regionally defined manner. SCs of the posterior midgut (PM) have been studied extensively, but the control of SCs in the middle midgut (MM) is less well understood. The MM contains a stomach-like copper cell region (CCR) that is regenerated by gastric stem cells (GSSCs) and contains acid-secreting copper cells (CCs). Bmp-like Decapentaplegic (Dpp) signaling determines the identity of GSSCs, and is required for CC regeneration, yet the precise control of Dpp signaling activity in this lineage remains to be fully established. Here, we show that Dad, a negative feedback regulator of Dpp signaling, is dynamically regulated in the GSSC lineage to allow CC differentiation. Dad is highly expressed in GSSCs and their first daughter cells, the gastroblasts (GBs), but has to be repressed in differentiating CCs to allow Dpp-mediated differentiation into CCs. We find that the Hox gene ultrabithorax (Ubx) is required for this regulation. Loss of Ubx prevents Dad repression in the CCR, resulting in defective CC regeneration. Our study highlights the need for dynamic control of Dpp signaling activity in the differentiation of the GSSC lineage and identifies Ubx as a critical regulator of this process.