Cytokines, hepatic cell profiling and cell interactions during bone marrow cell therapy for liver fibrosis in cholestatic mice

Modified Kasai operation combined with autologous bone marrow mononuclear cell infusion for biliary atresia

AIM

To evaluate the safety and outcomes of modified Kasai operation combined with autologous bone marrow mononuclear cell (BMMNC) infusion for biliary atresia (BA).

METHODS

A matched control study was conducted between January 2015 and December 2021. Ten consecutive children with biliary atresia (BA) who underwent the modified Kasai operation combined with autologous BMMNC infusion (cell therapy group) and ten children who had only the modified Kasai operation (control group) were included in the study. The Kasai operation was performed with two modifications: partial exteriorization of the liver, and encirclement with lateral retraction of two hepatic pedicles to facilitate the removal of fibrotic tissue. Bone marrow was harvested through anterior iliac crest under general anesthesia then a modified Kasai operation was performed. After processing, bone marrow mononuclear cells were infused through the umbilical vein at the end of the operation. Serum bilirubin, albumin, alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, and prothrombin time were monitored at baseline, six months, twelve months, and the last follow-up (4.5 years) after the operation. In addition, esophagoscopy and liver biopsies were performed on patients whose parents agreed. Mixed-effects analysis was used to evaluate the changes in Pediatric End-Stage Liver Disease (PELD) scores.

RESULTS

There were no intraoperative or postoperative complications related to the operation or cell infusion. The average infused BMMNC and CD34 + cell counts per kg bodyweight were 85.5 ± 56.0 × 106/kg and 10.0 ± 3.6 × 106 for the injection, respectively. Following the intervention, all ten patients in the cell therapy group survived, with a mean follow-up duration of 4.5 ± 0.9 years. Meanwhile, three patients in the control group died due to end-stage liver failure, with a mean follow-up time of 4.3 ± 0.9 years. Liver function of the cell therapy group was maintained or improved after the operation and cell infusion, as assessed by biochemical tests. The disease severity reduced markedly in the CT group compared to the control group, with a significant reduction in PELD scores (p < 0.05).

CONCLUSION

Autologous BMMNC administration combined with Kasai operation for BA is safe and may maintain or improve liver function in the studied patients.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05517317 on August 26th, 2022.

Sulforaphane Exerts Beneficial Immunomodulatory Effects on Liver Tissue via a Nrf2 Pathway-Related Mechanism in a Murine Model of Hemorrhagic Shock and Resuscitation

Our research explores the immunomodulatory effects of sulforaphane (SFN), a well-known nuclear factor erythroid 2-related factor 2 (Nrf2) pathway agonist, on the sterile inflammation of and ischemia-reperfusion injuries to the liver after hemorrhagic shock (HS) followed by resuscitation (R). Male C57/BL6 wild-type and transgenic ARE-luc mice were exposed to mean arterial pressure-controlled HS. Fluid resuscitation was performed after 90 min of HS, and SFN was administrated intraperitoneally after that. The animals were sacrificed at 6 h, 24 h, and 72 h after resuscitation, and their livers were extracted to perform H&E staining and myeloperoxidase (MPO) activity analysis. The Kupffer cells were isolated for cytokines profile measurements and Nrf2 immunofluorescence staining. Further, the ARE-luc mice were used to assess hepatic Nrf2 activity in vivo. We identified that SFN-activated Kupffer cells’ Nrf2 pathway and modulated its cytokines expression, including TNF-α, MCP-1, KC/CXCL1, IL-6, and IL-10. Furthermore, SFN mitigated liver ischemia-reperfusion injury, as evidenced by the downregulation of the Suzuki score and the enhanced hepatic Nrf2 activity. The in vivo SFN treatment decreased neutrophils infiltration, as shown by the decreased MPO levels. Our study shows that SFN can decrease HS/R-induced hepatic ischemia-reperfusion injury and modulate the activity of Kupffer cells via an Nrf2-dependent pathway.

Autologous bone marrow mononuclear cell infusion for liver cirrhosis after the Kasai operation in children with biliary atresia

Aim

To evaluate the safety and early outcomes of autologous bone marrow mononuclear cell (BMMNC) infusion for liver cirrhosis due to biliary atresia (BA) after Kasai operation.

Methods

An open-label clinical trial was performed from January 2017 to December 2019. Nineteen children with liver cirrhosis due to BA after Kasai operation were included. Bone marrow was harvested through anterior iliac crest puncture under general anesthesia. Mononuclear cells (MNCs) were isolated by Ficoll gradient centrifugation and then infused into the hepatic artery. The same procedure was repeated 6 months later. Serum bilirubin, albumin, alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, and prothrombin time were monitored at baseline, 3 months, 6 months, and 12 months after the first transplantation. Esophagoscopies and liver biopsies were performed in patients whose parents provided consent. Mixed-effect analysis was used to evaluate the changes in Pediatric End-Stage Liver Disease (PELD) scores.

Results

The average MNC and CD34+ cell counts per kg body weight were 50.1 ± 58.5 × 10⁶/kg and 3.5 ± 2.8 × 10⁶ for the first transplantation and 57.1 ± 42.0 × 10⁶/kg and 3.7 ± 2.7 × 10⁶ for the second transplantation. No severe adverse events associated with the cell therapy were observed in the patients. One patient died 5 months after the first infusion at a provincial hospital due to the rupture of esophageal varices, while 18 patients survived. Liver function was maintained or improved after infusion, as assessed by biochemical tests. The severity of the disease reduced markedly, with a significant reduction in PELD scores.

Conclusion

Autologous BMMNC administration for liver cirrhosis due to BA is safe and may maintain or improve liver function.

Trial registration

ClinicalTrials.gov identifier: NCT03468699. Name of the registry: Vinmec Research Institute of Stem Cell and Gene Technology.

https://clinicaltrials.gov/ct2/show/NCT03468699?cond=biliary+atresia&cntry=VN&draw=2&rank=2. Registered on March 16, 2018. The trial results will also be published according to the CONSORT statement at conferences and reported in peer-reviewed journals.

Phosphodiesterase-5 inhibition improves bone regeneration at the early stages of ischemic osteonecrosis of the femoral head in rats

Posttraumatic osteonecrosis of the femoral head (ONFH) affects patients at different ages and may lead to functional limitation and joint replacement, with total hip arthroplasty, which is a costly procedure. Proposed methods to optimize ischemic tissue regeneration have been reported. Phosphodiesterase-5 inhibitors act by inhibiting the degradation of guanosine 3',5'-cyclic monophosphate in the nitric oxide pathway, increasing its bioavailability and promoting vascular endothelial growth factor (VEGF)-mediated neovascular recruitment and the induction of tissue regeneration in the traumatized bone. Thirty male Sprague-Dawley rats (6 months old) were subjected to an experimental model of traumatic ONFH divided into two groups, according to the administration of 5 mg/kg sildenafil or water (control group). Rats were then killed at 7, 14, and 21 days. Histological (Goldner's trichrome), histochemical (periodic acid-Schiff [PAS]), and immunohistochemical (VEGF and osteopontin [OPN]) techniques were used to quantify bone and vascular responses. Higher levels of VEGF (p < 0.01) and OPN (p < 0.01) immunostaining in the epiphysis, the greater formation of osteoid tissue (p < 0.01 on Day 7; p < 0.05 on Day 14), and higher levels of PAS staining (p < 0.01 on Day 7) were observed in the sildenafil-treated group. The present study demonstrated that sildenafil optimized bone tissue regeneration by increasing VEGF signaling and OPN expression, with increased bone formation (osteoid and carbohydrate macromolecule deposition) in the early stages following traumatic ischemic insult. Thus, sildenafil treatment may improve the prognosis of patients with osteonecrosis.

Effects of mesenchymal stem cells conditioned medium treatment in mice with cholestatic liver fibrosis

AIMS

The purpose of this work was to study the effects of mesenchymal stem cells conditioned medium (MSC CM) treatment in animals with cholestatic liver fibrosis.

MATERIALS AND METHODS

We induced cholestatic liver fibrosis by bile duct ligation in C57Bl/6 mice. In the 5th and 6th days after bile duct ligation proceeding, conditioned medium obtained of cultures of mesenchymal stem cells derived from adipose tissue was injected in the animals. Blood levels of hepatic transaminases, alkaline phosphatase and albumin were measured in each group. Analysis of collagen deposition was realized by Picro Sirius red staining and cytokine profiling was performed by cytometric bead array (CBA).

KEY FINDINGS

Our results showed that MSC CM treatment decreased levels of hepatic enzymes and collagen deposition in the liver. After MSC CM treatment, profibrotic IL-17A was decreased andIL-6 and IL-4 were increased.

SIGNIFICANCE

In summary, MSC CM treatment demonstrated therapeutic potential to cholestatic liver fibrosis, favoring matrix remodeling and cytokine profile towards liver regeneration.

Mechanisms Underlying Cell Therapy in Liver Fibrosis: An Overview

Fibrosis is a common feature in most pathogenetic processes in the liver, and usually results from a chronic insult that depletes the regenerative capacity of hepatocytes and activates multiple inflammatory pathways, recruiting resident and circulating immune cells, endothelial cells, non-parenchymal hepatic stellate cells, and fibroblasts, which become activated and lead to excessive extracellular matrix accumulation. The ongoing development of liver fibrosis results in a clinically silent and progressive loss of hepatocyte function, demanding the constant need for liver transplantation in clinical practice, and motivating the search for other treatments as the chances of obtaining compatible viable livers become scarcer. Although initially cell therapy has emerged as a plausible alternative to organ transplantation, many factors still challenge the establishment of this technique as a main or even additional therapeutic tool. Herein, the authors discuss the most recent advances and point out the corners and some controversies over several protocols and models that have shown promising results as potential candidates for cell therapy for liver fibrosis, presenting the respective mechanisms proposed for liver regeneration in each case.

Beneficial and Deleterious Effects of Female Sex Hormones, Oral Contraceptives, and Phytoestrogens by Immunomodulation on the Liver

The liver is considered the laboratory of the human body because of its many metabolic processes. It accomplishes diverse activities as a mixed gland and is in continuous cross-talk with the endocrine system. Not only do hormones from the gastrointestinal tract that participate in digestion regulate the liver functions, but the sex hormones also exert a strong influence on this sexually dimorphic organ, via their receptors expressed in liver, in both health and disease. Besides, the liver modifies the actions of sex hormones through their metabolism and transport proteins. Given the anatomical position and physiological importance of liver, this organ is evidenced as an immune vigilante that mediates the systemic immune response, and, in turn, the immune system regulates the hepatic functions. Such feedback is performed by cytokines. Pro-inflammatory and anti-inflammatory cytokines are strongly involved in hepatic homeostasis and in pathological states; indeed, female sex hormones, oral contraceptives, and phytoestrogens have immunomodulatory effects in the liver and the whole organism. To analyze the complex and interesting beneficial or deleterious effects of these drugs by their immunomodulatory actions in the liver can provide the basis for either their pharmacological use in therapeutic treatments or to avoid their intake in some diseases.

Bone marrow derived-mesenchymal stem cells downregulate IL17A dependent IL6/STAT3 signaling pathway in CCl4-induced rat liver fibrosis

Therapeutic potential of bone marrow–derived mesenchymal stem cells (BM-MSCs) has been reported in several animal models of liver fibrosis. Interleukin (IL) 17A, IL6 and Stat3 have been described to play crucial roles in chronic liver injury. However, the modulatory effect of MSCs on these markers was controversial in different diseases. BM-MSCs might activate the IL6/STAT3 signaling pathway and promote cell invasion in hepatocellular carcinoma, but the immunomodulatory role of BM-MSCs on IL17A/IL6/STAT3 was not fully elucidated in liver fibrosis. In the present study, we evaluated the capacity of the BM-MSCs in the modulation of cytokines milieu and signal transducers, based on unique inflammatory genes Il17a and Il17f and their receptors Il17rc and their effect on the IL6/STAT3 pathway in CCl₄-induced liver fibrosis in rats. A single dose of BM-MSCs was administered to the group with induced liver fibrosis, and the genes and proteins of interest were evaluated along six weeks after treatment. Our results showed a significant downregulation of Il17a, Il17ra, il17f and Il17rc genes. In accordance, BM-MSCs administration declined IL17, IL2 and IL6 serum proteins and downregulated IL17A and IL17RA proteins in liver tissue. Interestingly, BM-MSCs downregulated both Stat3 mRNA expression and p-STAT3, while Stat5a gene was downregulated and p-STAT5 protein was elevated. Also P-SMAD3 and TGFβR2 proteins were downregulated in response to BM-MSCs treatment. Collectively, we suggest that BM-MSCs might play an immunomodulatory role in the treatment of liver fibrosis through downregulation of IL17A affecting IL6/STAT3 signaling pathway.