Analysis of structural components of decellularized scaffolds in renal fibrosis

Suyin Detoxification Prescription Regulates the Klotho and ERK/NF-κB Signaling Pathways to Alleviate Renal Injury

Chronic Kidney Disease (CKD) is an irreversible pathological condition resulting from the gradual accumulation of nephrotoxic substances. The application of the "Kidney Toxicity" theory in CKD treatment holds significant research potential and promising clinical prospects. We established a murine model of unilateral ureteral obstruction (UUO) and administered the traditional Chinese medicine prescription Suyin detoxification prescription (SDP). The efficacy of SDP was assessed by comparing the expression levels of Klotho, NF-κB, pNF-κB, VEGF, α-SMA, pERK1/2, and ERK1/2 proteins with those in the Sham operation group using immunohistochemistry, RT-qPCR, and Western Blot techniques. The study revealed a significant reduction in the expression of Klotho and VEGF proteins during the progression of renal fibrosis in mice, while there was a marked increase in the levels of pNF-κB, α-SMA, and pERK1/2 proteins, demonstrating statistical significance (p < 0.05). In UUO mice treated with a high dose of SDP, these proteins exhibited an opposite expression trend compared to that observed in pure operated model mice, with statistically significant differences (p < 0.05). Subsequently, we investigated the relationship between Klotho protein and the ERK/NF-κB signaling pathway-related proteins in human umbilical vein endothelial cells (HUVECs). Knockdown of Klotho protein in HUVECs confirmed its potential as a target for SDP's renal protective effects in vivo by regulating ERK/NF-κB signaling pathway-related proteins to some extent. The renoprotective effect of SDP is mediated through modulation of Klotho protein expression in renal tissues, thereby influencing the ERK/NF-κB signaling pathway and ameliorating the inflammatory processes associated with renal fibrosis. The present study has significantly contributed to the advancement and refinement of the pathogenesis of "Kidney Toxicity" as well as the therapeutic approach of "Kidney Detoxification".

Current strategies on kidney regeneration using tissue engineering approaches: a systematic review

INTRODUCTION

Over the past two decades, there has been a notable rise in the number of individuals afflicted with End-Stage Renal Disease, resulting in an increased demand for renal replacement therapies. While periodic dialysis is beneficial, it can negatively impact a patient's quality of life and does not fully replicate the secretory functions of the kidneys. Additionally, the scarcity of organ donors and complications associated with organ transplants have underscored the importance of tissue engineering. Regenerative medicine is revolutionized by developing decellularized organs and tissue engineering, which is considered a cutting-edge area of study with enormous potential. Developing bioengineered kidneys using tissue engineering approaches for renal replacement therapy is promising.

METHOD AND MATERIALS

We aimed to systematically review the essential preclinical data to promote the translation of tissue engineering research for kidney repair from the laboratory to clinical practice. A PubMed search strategy was systematically implemented without any linguistic restrictions. The assessment focused on complete circumferential and inlay procedures, thoroughly evaluating parameters such as cell seeding, decellularization techniques, recellularization protocols, and biomaterial types.

RESULTS

Of the 1,484 studies retrieved from the following primary searches, 105 were included. Kidneys were harvested from eight different species. Nine studies performed kidney decellularization from discarded human kidneys. Sixty-four studies performed whole organ decellularization. Some studies used acellular scaffolds to produce hydrogels, sheets, and solutions. Decellularization is achieved through physical, chemical, or enzymatic treatment or a combination of them. Sterilization of acellular scaffolds was also thoroughly and comparatively evaluated. Lastly, different recellularization protocols and types of cells used for further cell seeding were demonstrated.

CONCLUSION

A comprehensive review of the existing literature about kidney tissue engineering was conducted to evaluate its effectiveness in preclinical investigations. Our findings indicate that enhancements in the design of preclinical studies are necessary to facilitate the successful translation of tissue engineering technologies into clinical applications.

Recent advances in extracellular matrix manipulation for kidney organoid research

The kidney plays a crucial role in maintaining the body's microenvironment homeostasis. However, current treatment options and therapeutic agents for chronic kidney disease (CKD) are limited. Fortunately, the advent of kidney organoids has introduced a novel in vitro model for studying kidney diseases and drug screening. Despite significant efforts has been leveraged to mimic the spatial-temporal dynamics of fetal renal development in various types of kidney organoids, there is still a discrepancy in cell types and maturity compared to native kidney tissue. The extracellular matrix (ECM) plays a crucial role in regulating cellular signaling, which ultimately affects cell fate decision. As a result, ECM can refine the microenvironment of organoids, promoting their efficient differentiation and maturation. This review examines the existing techniques for culturing kidney organoids, evaluates the strengths and weaknesses of various types of kidney organoids, and assesses the advancements and limitations associated with the utilization of the ECM in kidney organoid culture. Additionally, it presents a discussion on constructing specific physiological and pathological microenvironments using decellularized extracellular matrix during certain developmental stages or disease occurrences, aiding the development of kidney organoids and disease models.

ECM-derived biomaterials for regulating tissue multicellularity and maturation

Recent breakthroughs in developing human-relevant organotypic models led to the building of highly resemblant tissue constructs that hold immense potential for transplantation, drug screening, and disease modeling. Despite the progress in fine-tuning stem cell multilineage differentiation in highly controlled spatiotemporal conditions and hosting microenvironments, 3D models still experience naive and incomplete morphogenesis. In particular, existing systems and induction protocols fail to maintain stem cell long-term potency, induce high tissue-level multicellularity, or drive the maturity of stem cell-derived 3D models to levels seen in their in vivo counterparts. In this review, we highlight the use of extracellular matrix (ECM)-derived biomaterials in providing stem cell niche-mimicking microenvironment capable of preserving stem cell long-term potency and inducing spatial and region-specific differentiation. We also examine the maturation of different 3D models, including organoids, encapsulated in ECM biomaterials and provide looking-forward perspectives on employing ECM biomaterials in building more innovative, transplantable, and functional organs.

A biomimetic renal fibrosis progression model on-chip evaluates anti-fibrotic effects longitudinally in a dynamic fibrogenic niche

Although renal fibrosis can advance chronic kidney disease and progressively lead to end-stage renal failure, no effective anti-fibrotic drugs have been clinically approved. To aid drug development, we developed a biomimetic renal fibrosis progression model on-chip to evaluate anti-fibrotic effects of natural killer cell-derived extracellular vesicles and pirfenidone (PFD) across different fibrotic stages. First, the dynamic interplay between fibroblasts and kidney-derived extracellular matrix (ECM) resembling the fibrogenic niche on-chip demonstrated that myofibroblasts induced by stiff ECM in 3 days were reversed to fibroblasts by switching to soft ECM, which was within 2, but not 7 days. Second, PFD significantly down-regulated the expression of α-SMA in NRK-49F in medium ECM, as opposed to stiff ECM. Third, a study in rats showed that early administration of PFD significantly inhibited renal fibrosis in terms of the expression levels of α-SMA and YAP. Taken together, both on-chip and animal models indicate the importance of early anti-fibrotic intervention for checking the progression of renal fibrosis. Therefore, this renal fibrosis progression on-chip with a feature of recapitulating dynamic biochemical and biophysical cues can be readily used to assess anti-fibrotic candidates and to explore the tipping point when the fibrotic fate can be rescued for better medical intervention.

Biomimetic hydrogel derived from decellularized dermal matrix facilitates skin wounds healing

Cutaneous wound healing affecting millions of people worldwide represents an unsolvable clinical issue that is frequently challenged by scar formation with dramatical pain, impaired mobility and disfigurement. Herein, we prepared a kind of light-sensitive decellularized dermal extracellular matrix-derived hydrogel with fast gelling performance, biomimetic porous microstructure and abundant bioactive functions. On account of its excellent cell biocompatibility, this ECM-derived hydrogel could induce a marked cellular infiltration and enhance the tube formation of HUVECs. In vivo experiments based upon excisional wound splinting model showed that the hydrogel prominently imparted skin wound healing, as evidenced by notably increased skin appendages and well-organized collagen expression, coupled with significantly enhanced angiogenesis. Moreover, the skin regeneration mediated by this bioactive hydrogel was promoted by an accelerated M1-to-M2 macrophage phenotype transition. Consequently, the decellularized dermal matrix-derived bioactive hydrogel orchestrates the entire skin healing microenvironment to promote wound healing and will be of high value in treatment of cutaneous wound healing. As such, this biomimetic ddECMMA hydrogel provides a promising versatile opinion for the clinical translation.

In vitro study of decellularized rat tissues for nerve regeneration

Peripheral nerve injuries cause an absence or destruction of nerves. Decellularized nerves, acting as a replacement for autografts, have been investigated in the promotion of nerve repair and regeneration, always being incorporated with stem cells or growth factors. However, such a strategy is limited by size availability. The potential application in heterotopic transplantation of other decellularized tissues needs to be further explored. In this study, rat decellularized kidney (dK) was selected to be compared with decellularized peripheral nerve (dN), since dK has aboundant ECM components and growth factors. The PC-12 cells were cultured on dK and dN scaffolds, as shown in the similar behaviors of cell metabolism and viability, but have a more regular arrangement on dN compared to dK, indicating that the natural structure plays an important role in guiding cell extension. However, we found significant upregulation of axon–growth–associated genes and proteins of PC-12 cells in the dK group compared to the dN group by qRT-PCR, immunofluorescence, and western blotting. Furthermore, various neurotrophic factors and growth factors of acellular kidney and nerve were evaluated by ELISA assay. The lower expression of neurotrophic factors but higher expression of growth factors such as VEGF and HGF from dK suggests that axon growth and extension for PC-12 cells may be partially mediated by VEGF and HGF expression from decellularized kidney, which further points to a potential application in nerve repair and regeneration.

Recent advancement of decellularization extracellular matrix for tissue engineering and biomedical application

BACKGROUND

Decellularized extracellular matrixs (dECMs) derived from organs and tissues have emerged as a promising tool, as they encompass the characteristics of an ideal tissue scaffold: complex composition, vascular networks and unique tissue-specific architecture. Consequently, their use has propagated throughout tissue engineering and regenerative medicine. dECM can be easily obtained from various tissues/organs by appropriate decellularization protocolsand is entitled to provide necessary cues to cells homing.

METHODS

In this review, we describe the decellularization and sterilization methods that are commonly used in recent research, the effects of these methods upon biologic scaffold material are discussed. Also, we summarize the recent developments of recellularization and vascularization techniques in regeneration medicine. Additionally, dECM preservation methods is mentioned, which provides the basis for the establishment of organ bank.

RESULTS

Biomedical applications and the status of current research developments relating to dECM biomaterials are outlined, including transplantation in vivo, disease models and drug screening, organoid, 3D bioprinting, tissue reconstruction and rehabilitation and cell transplantation and culture. Finally, critical challenges and future developing technologies are discussed.

CONCLUSIONS

With the development of tissue engineering and regenerative medicine, dECM will have broader applications in the field of biomedicine in the near future.

Matrisome provides a supportive microenvironment for oral squamous cell carcinoma progression

Oral squamous cell carcinoma (OSCC) is a common pernicious tumor in the head and neck regions. However, the function of tumor extracellular matrix (ECM) has not been elucidated. A tissue engineering method was applied for remodeling ECM through decellularization. The cellular components were removed, and the biological composition was mostly preserved. Proteomics was performed to analyze the characterization between normal and tumor ECM. According to LC-MS/MS results, 26 proteins just showed in tumor ECM, and 14 proteins only showed in late-stage tumor ECM. KEGG pathway analysis showed that most variant proteins were linked to metabolic regulation and tumor immunity (such as SCC-Ag1, LOX). To affirm the influence of tumor ECM on the progression of OSCC, tumor cells and macrophages were co-cultured with ECM scaffold. Marked differences in proliferation, apoptosis, and migration of OSCC cells were observed between tumor and normal ECM. Tumor ECM polarized macrophages towards an anti-inflammatory phenotype (higher IL-10 and CD68, and relatively lower CD86 and IL1-β). Collectively, these findings suggest that tumor ECM served as a permissive role in OSCC progression. SIGNIFICANCE: The variation between OSCC ECM and normal ECM confirm tumor ECM plays a significant role in OSCC deterioration, which is conducive to exploring the occurrence and progression mechanisms of OSCC, and further improving the curative effect of this disease.