Augmenter of liver regeneration ameliorates ischemia-reperfusion injury in steatotic liver via inhibition of the TLR4/NF-κB pathway

Omeprazole taken once every other day can effectively prevent aspirin-induced gastrointestinal mucosal damage in rats

BACKGROUND

Proton-pump inhibitors (PPIs) prevent aspirin-associated gastric and duodenal mucosal damage. However, long-term use of PPIs can lead to various adverse reactions, such as gastric polyps and enterochromaffin-like cell hyperplasia. Current research indicates that the abovementioned adverse reactions are mainly related to hypergastrinemia. We investigated whether low-frequency administration of omeprazole could effectively repair aspirin-induced mucosal damage and reduce the increase in gastrin levels associated with long-term use of PPIs.

METHODS

Sprague‒Dawley rats were divided into four treatment groups: daily aspirin, daily aspirin and omeprazole once every day (qd), daily aspirin and omeprazole once every other day (qod), and daily aspirin and omeprazole once every three days (1/d3). After 15 days of feeding, blood samples were collected, and the stomachs of sacrificed rats were subjected to macroscopic, histological, and immunohistochemical studies. Moreover, in clinical practice, patients with peptic ulcers caused by aspirin took a standard dose of omeprazole (20 mg) every other day. Two months later, gastroscopy was performed to examine the healing of the ulcers.

RESULTS

Both the omeprazole qd and omeprazole qod administrations effectively prevented aspirin-induced gastric peptic ulcers, with no significant difference between the two groups in the inhibition of parietal cell secretion of gastric acid and cell apoptosis. However, omeprazole 1/d3 failed to completely prevent aspirin-induced gastric mucosal injury. Notably, the gastrin levels, cell proliferation ability and cholecystokinin B receptor expression of the omeprazole qd group were significantly higher than those of the omeprazole qod group. In clinical work, patients with peptic ulcers caused by aspirin were given a standard dose of omeprazole every other day, and their ulcers healed after 2 months, as observed by gastroscopy.

CONCLUSIONS

Omeprazole administration once every other day can effectively prevent aspirin-induced peptic ulcers and reduce hypergastrinemia, which may reduce the long-term adverse effects of PPI treatment.

Knockdown of protein interacting with C α kinase 1 aggravates sepsis-induced acute liver injury by regulating the TLR4/NF-κB pathway

Acute liver injury (ALI) may manifest at any phase of sepsis, yet an explicit therapeutic approach remains elusive. In this study, LPS and cecum ligation and puncture (CLP) were utilized to establish an inflammatory cell model and a murine model of sepsis-induced liver injury, respectively, aiming to explore the potential protective effect of protein interacting with C α kinase 1 (PICK1) on sepsis-induced ALI and its underlying mechanisms. In both the cell supernatant and the murine whole blood, the concentrations of inflammatory factors were quantified by ELISA, while the protein and mRNA expressions of PICK1, cleaved-PARP-1, caspase1, TLR4, IκBα, and NF-κB were assessed via western blot and qRT-PCR. The outcomes revealed that the knockdown of PICK1 increased the levels of inflammatory factors and apoptosis, alongside activation of TLR4/NF-κB signaling pathway-related factors in both in vivo and in vitro models. Moreover, the murine liver samples were subjected to Hematoxylin-Eosin (HE) staining for assessment of histopathological morphology. The HE staining and liver injury scoring results manifested a markedly exacerbated hepatic damage in PICK1 knockout mice as compared to WT mice following CLP. Furthermore, the liver macrophages were isolated from murine livers, and the expression and activity of the factors associated with the TLR4/NF-κB signaling pathway were verified through RT-qPCR and western blot, and EMSA assay demonstrated an augmented NF-κB activity subsequent to PICK1 knockout. Finally, the expression and localization of PICK1 in macrophages were further scrutinized via immunofluorescence, and the interaction between PICK1 and TLR4 was identified through co-immunoprecipitation. In conclusion, the knockdown of PICK1 appeared to modulate inflammatory factors by activating the TLR4/NF-κB signaling pathway, thereby exacerbating hepatic damage induced by sepsis.

Machine perfusion of the liver and bioengineering

With the increasing number of accepted candidates on waiting lists worldwide, there is an urgent need to expand the number and the quality of donor livers. Dynamic preservation approaches have demonstrated various benefits, including improving liver function and graft survival, and reducing liver injury and post-transplant complications. Consequently, organ perfusion techniques are being used in clinical practice in many countries. Despite this success, a proportion of livers do not meet current viability tests required for transplantation, even with the use of modern perfusion techniques. Therefore, devices are needed to further optimise machine liver perfusion - one promising option is to prolong machine liver perfusion for several days, with ex situ treatment of perfused livers. For example, stem cells, senolytics, or molecules targeting mitochondria or downstream signalling can be administered during long-term liver perfusion to modulate repair mechanisms and regeneration. Besides, today's perfusion equipment is also designed to enable the use of various liver bioengineering techniques, to develop scaffolds or for their re-cellularisation. Cells or entire livers can also undergo gene modulation to modify animal livers for xenotransplantation, to directly treat injured organs or to repopulate such scaffolds with "repaired" autologous cells. This review first discusses current strategies to improve the quality of donor livers, and secondly reports on bioengineering techniques to design optimised organs during machine perfusion. Current practice, as well as the benefits and challenges associated with these different perfusion strategies are discussed.

Effects of somatostatin in combination with early hemoperfusion on inflammatory, hemorheological and oxidative parameters during the treatment of acute pancreatitis

We aimed to evaluate the effects of somatostatin combined with early hemoperfusion on inflammatory and stress responses during acute pan-creatitis (AP) treatment.A total of 159 AP patients treated from September 2016 to January 2020 were randomly divided into three groups A-C (n=53). In addition to routine treatment, groups A-C were additionally given somatostatin, early hemoperfusion, and somatostatin combined with early hemoperfusion, re-spectively. Their inflammatory factors, stress response, intestinal mucosal bar-rier, hemorheological indices, recovery time, length of stay, clinical efficacy, and adverse reactions were compared. The levels of serum interleukin-10 (IL -10), catalase and glutathione peroxidase rose in the three groups after ten days of treatment, compared with values before treatment, being the highest rise in group C. The levels of IL -18, tumor necrosis factor-α, soluble intercellular adhe-sion molecule-1, procalcitonin, high mobility group protein B1, lipid hydrogen peroxide, advanced oxidation protein products, epinephrine, cortisol, D-lactic acid, diamine oxidase, and endotoxin decreased after ten days of treatment compared with those before treatment, which were lowest in group C (P<0.05). After ten days of treatment, the levels of hemorheological indices were signifi-cantly lower than those before treatment (P<0.05). Compared with groups A and B, group C had a shorter recovery time of urine amylase, bowel sound and passing gas, remission time of abdominal pain, length of stay, and a higher to-tal response rate (P<0.05).During AP treatment, somatostatin combined with early hemoperfusion effectively relieved inflammatory and stress responses, protected the intestinal mucosal barrier function and improved the hemorheol-ogy, thereby promoting the recovery and benefiting the prognosis of patients.

Protective mechanisms of telmisartan against hepatic ischemia/reperfusion injury in rats may involve PPARγ-induced TLR4/NF-κB suppression

Hepatic ischemia-reperfusion (I/R) is an important cause of liver damage in many clinical situations. Toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) is an inflammatory pathway activated in hepatic I/R injury. Telmisartan, a selective angiotensin II type 1 receptor antagonist and peroxisome proliferator-activated receptor-gamma (PPARγ) partial agonist, can inhibit the expression of pro-inflammatory cytokines. The present work investigated the possible protective effect of telmisartan against hepatic I/R injury and explored its possible mechanisms in rats. Rats were divided into four equal groups: sham-operated control, telmisartan-treated sham-operated control, I/R untreated, and I/R telmisartan-treated groups. Hepatic injury was evaluated biochemically by serum activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and histopathological examination. Hepatic oxidative stress biomarkers, myeloperoxidase level, PPARγ and TLR4 mRNA expression, and NF-κB and active caspase 3 immunoexpression were determined. The study showed that telmisartan attenuated hepatic I/R, as evidenced by decreased serum ALT and AST activities and confirmed by improvement of the histopathological changes. The protective effect of telmisartan was associated with modulation of oxidative stress parameters, myeloperoxidase level, PPARγ and TLR4 mRNA expression, and NF-κB and caspase 3 immunoexpression. Taken together, the current study showed that telmisartan could protect the rat liver from I/R injury. This hepatoprotective effect was attributed to, at least in part, increase in PPARγ expression and suppression of TLR4/NF-κB pathway.