Adipose-derived stem cell therapy for spinal cord injuries: Advances, challenges, and future directions.

Spinal cord injury (SCI) has limited treatment options for regaining function. Adipose-derived stem cells (ADSCs) show promise owing to their ability to differentiate into multiple cell types, promote nerve cell survival, and modulate inflammation. This review explores ADSC therapy for SCI, focusing on its potential for improving function, preclinical and early clinical trial progress, challenges, and future directions. Preclinical studies have demonstrated ADSC transplantation's effectiveness in promoting functional recovery, reducing cavity formation, and enhancing nerve regrowth and myelin repair. To improve ADSC efficacy, strategies including genetic modification and combination with rehabilitation are being explored. Early clinical trials have shown safety and feasibility, with some suggesting motor and sensory function improvements. Challenges remain for clinical translation, including optimizing cell survival and delivery, determining dosing, addressing tumor formation risks, and establishing standardized protocols. Future research should focus on overcoming these challenges and exploring the potential for combining ADSC therapy with other treatments, including rehabilitation and medication.

Cationic polymer effect on brown adipogenic induction of dedifferentiated fat cells.

Obesity and its associated comorbidities place a substantial burden on public health. Given the considerable potential of brown adipose tissue in addressing metabolic disorders that contribute to dysregulation of the body's energy balance, this area is an intriguing avenue for research. This study aimed to assess the impact of various polymers, including collagen type I, fibronectin, laminin, gelatin, gellan gum, and poly-l-lysine (PLL), on the in vitro brown adipogenic differentiation of dedifferentiated fat cells within a fibrin gel matrix. The findings, obtained through RT-qPCR, immunofluorescent imaging, ELISA assay, and mitochondria assessment, revealed that PLL exhibited a significant browning-inducing effect. Compared to fibrin-only brown-like drops after two weeks of incubation in brown adipogenic medium, PLL showed 6 (±3) times higher UCP1 gene expression, 5 (±2) times higher UCP1 concentration by ELISA assay, and 2 (±1) times higher mitochondrial content. This effect can be attributed to PLL's electrostatic properties, which potentially facilitate the cellular uptake of crucial brown adipogenic inducers such as the thyroid hormone, triiodothyronine (T3), and insulin from the induction medium.

Optimizing mesenchymal stem cell extracellular vesicles for chronic wound healing: Bioengineering, standardization, and safety.

Chronic wounds represent a significant global burden, afflicting millions with debilitating complications. Despite standard care, impaired healing persists due to factors like persistent inflammation and impaired tissue regeneration. Mesenchymal stem cell (MSC)-derived extracellular vesicles (EVs) offer an innovative regenerative medicine approach, delivering stem cell-derived therapeutic cargo in engineered nanoscale delivery systems. This review examines pioneering bioengineering strategies to engineer MSC-EVs into precision nanotherapeutics for chronic wounds. Emerging technologies like CRISPR gene editing, microfluidic manufacturing, and biomimetic delivery systems are highlighted for their potential to enhance MSC-EV targeting, optimize therapeutic cargo enrichment, and ensure consistent clinical-grade production. However, key hurdles remain, including batch variability, rigorous safety assessment for potential tumorigenicity, immunogenicity, and biodistribution profiling. Crucially, collaborative frameworks harmonizing regulatory science with bioengineering and patient advocacy hold the key to expediting global clinical translation. By overcoming these challenges, engineered MSC-EVs could catalyze a new era of off-the-shelf regenerative therapies, restoring hope and healing for millions afflicted by non-healing wounds.

Chronic Pain Following Breast Reconstruction: A Scoping Review.

BACKGROUND: Breast cancer survival rates have increased significantly, underscoring the importance of enhancing long-term health-related quality of life. Breast reconstruction following mastectomy has emerged as a common approach that contributes to improved health-related quality of life. Nonetheless, chronic pain following breast reconstruction is a prevalent issue that has a negative impact on overall well-being. METHODS: To examine recent findings on chronic pain after breast reconstruction and progress in pain management, we performed a review of the literature through independent searches using the MEDLINE database within NIH National Library of Medicine PubMed. RESULTS: The review suggested that autologous reconstruction causes chronic postsurgical pain, especially at specific donor sites, whereas implant-based reconstruction does not seem to increase the risk of chronic pain. Moreover, certain operational and patient factors are also associated with chronic pain. Appropriate pain management can reduce chronic pain and prevent the transition from acute to chronic pain. CONCLUSION: This scoping review evaluated the characteristics of long-term chronic pain after breast reconstruction. The findings provide patients with important treatment information and will assist with their decision on their preferred treatment.

Micronized cellular adipose matrix purified with a bladed connector contains abundant functional adipose stem cells.

INTRODUCTION: A specialized device equipped with a sharp blade filter has been developed to enable more efficient purification of a micronized cellular adipose matrix (MCAM) containing stem cells. The aim of this study is to compare the characteristics and functions of the population of stromal cells (mSVF) and cultured cells (mASCs) purified using this device with those of cSVF and cASCs obtained through conventional enzymatic purification. METHODS: Cell viability, proliferation capacity and yield were assessed. Characterization of stem cell potency was performed by analyzing cell surface markers including CD34, a marker of activated adipose-derived stem cells. The trilineage differentiation potential was evaluated using RT-PCR and histology. RESULTS: The yield rate of mSVF obtained from MCAM was significantly higher than that with the conventional method, although use of the device resulted in a slight decrease in cell viability. After culture, mASCs exhibited a remarkable clonogenic potential and significantly higher cell proliferation potential than cASCs. The mASCs also displayed a distinct pattern of ASC cell surface markers, increased expression of genes related to CD34, high pluripotency, and a high trilineage differentiation ability. CONCLUSION: The specialized device enhanced the yield of SVF and produced cells with high proliferation rates and characteristics that include expression of stem cell markers.

Polyelectrolyte nanofilms on cell surface can induce brown adipogenic differentiation of DFATs.

Obesity and its related health issues significantly burden public health systems. Brown adipose tissue holds promise for addressing metabolic disorders and balancing the body's energy, making it a key research focus. Stimulating brown adipogenesis from stem cells could advance regenerative medicine and healthcare. In our previous research, we discovered that poly-l-lysine (PLL) significantly stimulates brown adipogenesis in three-dimensional differentiation of dedifferentiated fat cells (DFATs) within fibrin gels. In this study, we evaluated polyelectrolyte (PE) nanofilms made of PLL and dextran sulfate, applied directly to DFAT surfaces to improve brown adipogenic differentiation through an innovative approach. This approach involved coating the DFAT surfaces with PE nanofilms, forming a multilayer structure that not only provided a supportive matrix but also facilitated the adsorption of essential molecules like T3 and insulin for brown adipogenesis. DFATs coated with three PE layers and encapsulated in fibrin gel showed a significant increase in the adipogenic marker UCP1 gene expression and content. This PLL-based PE nanofilm coating on DFAT surfaces can be a novel and crucial technology for promoting brown adipogenesis in regenerative medicine and healthcare.

Pain-relieving Effects of Autologous Fat Grafting in Breast Cancer Surgery: A Scoping Review.

Background: Chronic pain is relatively common after breast cancer surgery, including breast reconstruction. Autologous fat grafting (AFG) has gained attention as a novel method for breast reconstruction, and recent clinical studies have also shown effects of AFG on alleviation of chronic pain after breast cancer surgery. Our objective was to conduct a scoping review of studies that have examined these effects with clearly defined clinical outcomes. Methods: A literature search was conducted using three databases: PubMed, MEDLINE, and Google Scholar, following PRISMA guidelines and the Arkesy and O'Malley framework. The search focused on clinical studies of the effects of AFG on chronic pain after breast cancer surgery. All studies reporting functional outcomes, return to work, and secondary surgery in a repeat operation were identified. Results: Of the 148 studies identified in the search, 11 studies with a total of 684 patients were included in the review. The average volume of fat grafted was approximately 128 mL over an average of 1.6 sessions. The most common time point for assessment was 1 year post-AFG. In all studies with an evidence level of 3 or lower, AFG showed positive results in alleviating pain after breast cancer surgery. However, one of the three randomized controlled trials did not show clinically significant effects. Conclusions: Most of the studies examined in this review suggested pain-relieving effects of AFG. However, there was one randomized controlled trial in which these effects were not confirmed, indicating a need for further accumulation of cases and performance of new, well-designed randomized controlled trials.

A novel surgical correction using a combination of wave-like incision and Z-axis Z-plasty for congenital constriction band syndrome.

BACKGROUND: A congenital constriction band (CCB) is a relatively common anomaly among limb malformations. However, the number of cases treated at a given center is limited and differences in techniques used by surgeons at each facility have a significant impact on the treatment outcomes. Several surgical methods have been reported, but a standard technique that yields consistent satisfactory results is still needed. Here, we introduce a novel technique for the treatment of CCB syndrome that uses a combination of wave-like skin incision and Z-axis Z-plasty. PATIENTS AND METHODS: A wave-like incision was used for skin incision with the goals of achieving an accordion effect and a less noticeable post-operative scar. After the fibrous constriction band was completely excised, a Z-plasty of sufficient size in the Z-axis direction was performed on the dermis-inclusive adipose tissue. For over 10 years, this technique was applied to 11 sites in 6 patients. A retrospective study of the characteristics of these cases was performed, including age at surgery, gender, type of deformity, degree of constriction, types of examination, number of surgeries, and post-operative outcomes. RESULTS: In all patients, a normal contour of the limbs was achieved and the hourglass-like deformity caused by the constriction band was satisfactorily improved. No additional corrective surgeries were needed, there was no abnormal growth of the treated limbs, and scarring was aesthetically acceptable in all cases. CONCLUSION: The novel technique described here uses deep subcutaneous fat to correct the hourglass-like deformity and restores a normal limb contour, while the wave-like skin incision minimizes post-operative scarring.

Multivariate Analysis of Risk Factors for Complications in Pediatric Tissue Expansion.

BACKGROUND: Tissue expanders represent one of the main surgical options for skin reconstruction in cases of tumors, traumalike burn injury, scar contracture, and alopecia. However, the tissue expander device is also associated with complications such as infection and extrusion. The aim of this study was to analyze risk factors for major complications of use of tissue expanders in pediatric patients using multivariate analysis. METHODS: A retrospective, single-center observational study was performed over 10 years in pediatric patients who were treated with tissue expanders for tumors, nevus, scars, burn reconstruction, and alopecia from April 2012 to March 2022. The primary outcome was overall complications per operation and expander, including infection and extrusion. Ten predictor variables were included as risk factors based on previous studies and as new factors considered important from clinical experience. Univariate and multivariate logistic regression analyses were performed to identify risk factors for major complications such as expander infection or extrusion. RESULTS: The study included 44 patients who underwent 92 operations using 238 tissue expanders. The overall complication rate per expander was 14.3%. Univariate logistic regression analysis identified associations of younger age, number of expanders used per operation, history of infection, and tissue expander locations with a higher complication rate. In multivariate logistic regression analysis, younger age (odds ratio, 1.14; P = 0.043) was associated with a high likelihood of expander complications. CONCLUSIONS: Younger age is an independent risk factor for tissue expander complications in pediatric patients. This factor should be considered in preoperative planning and discussions with the patient's family.

Improving stability of human three dimensional skin equivalents using plasma surface treatment.

In developing three-dimensional (3D) human skin equivalents (HSEs), preventing dermis and epidermis layer distortion due to the contraction of hydrogels by fibroblasts is a challenging issue. Previously, a fabrication method of HSEs was tested using a modified solid scaffold or a hydrogel matrix in combination with the natural polymer coated onto the tissue culture surface, but the obtained HSEs exhibited skin layer contraction and loss of the skin integrity and barrier functions. In this study, we investigated the method of HSE fabrication that enhances the stability of the skin model by using surface plasma treatment. The results showed that plasma treatment of the tissue culture surface prevented dermal layer shrinkage of HSEs, in contrast to the HSE fabrication using fibronectin coating. The HSEs from plasma-treated surface showed significantly higher transepithelial electrical resistance compared to the fibronectin-coated model. They also expressed markers of epidermal differentiation (keratin 10, keratin 14 and loricrin), epidermal tight junctions (claudin 1 and zonula occludens-1), and extracellular matrix proteins (collagen IV), and exhibited morphological characteristics of the primary human skins. Taken together, the use of plasma surface treatment significantly improves the stability of 3D HSEs with well-defined dermis and epidermis layers and enhanced skin integrity and the barrier functions.

Design, synthesis, and biological evaluation of phenylcyclopropylamine-entinostat conjugates that selectively target cancer cells.

Small molecule-based selective cancer cell-targeting can be a desirable anticancer therapeutic strategy. Aiming to discover such small molecules, we previously developed phenylcyclopropylamine (PCPA)-drug conjugates (PDCs) that selectively release anticancer agents in cancer cells where lysine-specific demethylase 1 (LSD1) is overexpressed. In this work, we designed PCPA-entinostat conjugates for selective cancer cell targeting. PCPA-entinostat conjugate 12 with a 4-oxybenzyl group linker released entinostat in the presence of LSD1 in in vitro assays and selectively inhibited the growth of cancer cells in preference to normal cells, suggesting the potential of PCPA-entinostat conjugates as novel anticancer drug delivery small molecules.

Evaluation of adipogenesis over time using a novel bioabsorbable implant without the addition of exogenous cells or growth factors.

Background: Breast reconstruction is crucial for patients who have undergone mastectomy for breast cancer. Our bioabsorbable implants comprising an outer poly-l-lactic acid mesh and an inner component filled with collagen sponge promote and retain adipogenesis in vivo without the addition of exogenous cells or growth factors. In this study, we evaluated adipogenesis over time histologically and at the gene expression level using this implant in a rodent model. Methods: The implants were inserted in the inguinal and dorsal regions of the animals. At 1, 3, 6, and 12 months post-operation, the weight, volume, and histological assessment of all newly formed tissue were performed. We analyzed the formation of new adipose tissue using multiphoton microscopy and RNA sequencing. Results: Both in the inguinal and dorsal regions, adipose tissue began to form 1 month post-operation in the peripheral area. Angiogenesis into implants was observed until 3 months. At 6 months, microvessels matured and the amount of newly generated adipose tissue peaked and was uniformly distributed inside implants. The amount of newly generated adipose tissue decreased from 6 to 12 months but at 12 months, adipose tissue was equivalent to the native tissue histologically and in terms of gene expression. Conclusions: Our bioabsorbable implants could induce normal adipogenesis into the implants after subcutaneous implantation. Our implants can serve as a novel and safe material for breast reconstruction without requiring exogenous cells or growth factors.

An Effective Approach to Collecting Lymph Vessels Using a Small Diameter Wire for Lymphaticovenous Anastomosis in Upper Limb Lymphedema.

Lymphaticovenous anastomosis (LVA), which involves connecting lymphatic vessels to veins under a microscope, is widely performed around the world as a surgical treatment for lymphedema due to its relatively low patient burden and consistent efficacy. One of the crucial points of LVA is identifying suitable lymphatic vessels from among many lymphatic vessels and connecting them at the most effective site, but in practice, this is not easy to do. To overcome this issue, we have been able to effectively drain lymph by connecting lymphatic vessels to veins just before the occluded site using a lymphatic wire that was just recently developed in Japan. The device guides the subcutaneous deep collecting lymphatic vessels from the peripheral relatively superficial lymphatic vessels. While this special wire is typically adapted in the lower limbs, we have confirmed its effectiveness in upper limb lymphedema as well. Overall, this approach shows promise for improving the accuracy and success rates of LVA procedures, which can have significant benefits for patients with upper limb lymphedema. In this article, we share our experience using lymphatic wire for upper limb lymphedema cases.