The liver is known as an organ with high proliferation potential. Clarifying the cellular origin and deepening the understanding of liver regeneration mechanisms will help provide new directions for ...the treatment of liver disease. With the development and application of lineage tracing technology, the specific distribution and dynamic changes of hepatocyte subpopulations in homeostasis and liver injury have been illustrated. Self‐replication of hepatocytes is responsible for the maintenance of liver function and mass under homeostasis. The compensatory proliferation of remaining hepatocytes is the main mechanism of liver regeneration following acute and chronic liver injury. Transdifferentiation between hepatocytes and cholangiocytes has been recognized upon severe chronic liver injury. Wnt/β‐catenin, Hippo/YAP and Notch signalling play essential roles in the maintenance of homeostatic liver and hepatocyte‐to‐cholangiocyte conversion under liver injury. In this review, we summarized the recent studies on cell origin of newly generated hepatocytes and the underlying mechanisms of liver regeneration in homeostasis and liver injury.
Background
Diagnostic criteria for sarcopenia have not been established in Chinese. This study established criteria based on the L3‐skeletal muscle index (L3‐SMI) and assessed its value for outcomes ...predicting in cirrhotic Chinese patients.
Methods
Totally 911 subjects who underwent a CT scan at two centres were enrolled in Cohort 1 (394 male and 417 female subjects, aged 20–80 years). The data of those subjects younger than 60 years (365 male and 296 female subjects) were used to determine the reference intervals of the L3‐SMI and its influencing factors. Cohort 2 consisted of 480 patients (286 male and 184 female patients) from three centres, and their data were used to investigate the prevalence of sarcopenia and evaluate the value of L3‐SMI for predicting the prognosis and complications of cirrhosis.
Results
Age and sex had the greatest effects on the L3‐SMI (P < 0.001). The L3‐SMI scores were clearly higher in male patients than in female patients (52.94 ± 8.41 vs. 38.91 ± 5.65 cm2/m2, P < 0.001) and sharply declined in subjects aged ≥ 60 years. Based on the mean −1.28 × SD among adults aged < 60 years, the L3‐SMI cut‐off value for sarcopenia was 44.77 cm2/m2 in male patients and 32.50 cm2/m2 in female patients. Using these values, 22.5% of the cirrhotic patients (28.7% of male patients and 11.9% of female patients) were diagnosed with sarcopenia. Compared with non‐sarcopenia individuals, sarcopenia patients had lower body mass index (21.28 ± 3.01 vs. 24.09 ± 3.39 kg/m2, P < 0.001) and serum albumin levels (31.54 ± 5.93 vs. 32.93 ± 5.95 g/L, P = 0.032), longer prothrombin times (16.39 ± 3.05 vs. 15.71 ± 3.20 s, P = 0.049), higher total bilirubin concentrations (41.33 ± 57.38 vs. 32.52 ± 31.48 μmol/L, P = 0.039), worse liver function (Child–Pugh score, 8.05 ± 2.11 vs. 7.32 ± 2.05, P = 0.001), higher prevalence of cirrhosis‐related complications (81.82% vs. 62.24%, P < 0.001) and mortality (30.68% vs. 11.22%, P < 0.001). Overall survival was significantly lower in the sarcopenia group risk ratio (RR) = 2.643, 95% confidence interval (CI) 1.646–4.244, P < 0.001, accompanied with an increased cumulative incidence of ascites (RR = 1.827, 95% CI 1.259–2.651, P = 0.002), spontaneous bacterial peritonitis (RR = 3.331, 95% CI 1.404–7.903, P = 0.006), hepatic encephalopathy (RR = 1.962, 95% CI 1.070–3.600, P = 0.029), and upper gastrointestinal varices (RR = 2.138, 95% CI 1.319–3.466, P = 0.002). Subgroup analysis showed sarcopenia shortened the survival of the patients with Model For End‐Stage Liver Disease score > 14 (RR = 4.310, 95% CI 2.091–8.882, P < 0.001) or Child–Pugh C (RR = 3.081, 95% CI 1.516–6.260, P = 0.002).
Conclusions
Sarcopenia is a common comorbidity of cirrhosis and can be used to predict cirrhosis‐related complications and the prognosis.
NAD(P)H dehydrogenase-like (NDH) complex NDH-1L of cyanobacteria plays a crucial role in cyclic electron flow (CEF) around photosystem I and respiration processes. NDH-1L couples the electron ...transport from ferredoxin (Fd) to plastoquinone (PQ) and proton pumping from cytoplasm to the lumen that drives the ATP production. NDH-1L-dependent CEF increases the ATP/NADPH ratio, and is therefore pivotal for oxygenic phototrophs to function under stress. Here we report two structures of NDH-1L from Thermosynechococcus elongatus BP-1, in complex with one Fd and an endogenous PQ, respectively. Our structures represent the complete model of cyanobacterial NDH-1L, revealing the binding manner of NDH-1L with Fd and PQ, as well as the structural elements crucial for proper functioning of the NDH-1L complex. Together, our data provides deep insights into the electron transport from Fd to PQ, and its coupling with proton translocation in NDH-1L.
Treatment of severe Coronavirus Disease 2019 (COVID-19) is challenging. We performed a phase 2 trial to assess the efficacy and safety of human umbilical cord-mesenchymal stem cells (UC-MSCs) to ...treat severe COVID-19 patients with lung damage, based on our phase 1 data. In this randomized, double-blind, and placebo-controlled trial, we recruited 101 severe COVID-19 patients with lung damage. They were randomly assigned at a 2:1 ratio to receive either UC-MSCs (4 × 10
cells per infusion) or placebo on day 0, 3, and 6. The primary endpoint was an altered proportion of whole lung lesion volumes from baseline to day 28. Other imaging outcomes, 6-minute walk test (6-MWT), maximum vital capacity, diffusing capacity, and adverse events were recorded and analyzed. In all, 100 COVID-19 patients were finally received either UC-MSCs (n = 65) or placebo (n = 35). UC-MSCs administration exerted numerical improvement in whole lung lesion volume from baseline to day 28 compared with the placebo (the median difference was -13.31%, 95% CI -29.14%, 2.13%, P = 0.080). UC-MSCs significantly reduced the proportions of solid component lesion volume compared with the placebo (median difference: -15.45%; 95% CI -30.82%, -0.39%; P = 0.043). The 6-MWT showed an increased distance in patients treated with UC-MSCs (difference: 27.00 m; 95% CI 0.00, 57.00; P = 0.057). The incidence of adverse events was similar in the two groups. These results suggest that UC-MSCs treatment is a safe and potentially effective therapeutic approach for COVID-19 patients with lung damage. A phase 3 trial is required to evaluate effects on reducing mortality and preventing long-term pulmonary disability. (Funded by The National Key R&D Program of China and others. ClinicalTrials.gov number, NCT04288102.
A maternal woman was positive for SARS-CoV-2 tested in throat swabs but negative tested in other body fluids, and she had IgG and IgA detected in breast milk. Her infant negative for SARS-CoV-2 at ...birth had elevated IgG in serum but quickly decayed. These findings suggest that breastfeeding might have the potential benefit to the neonates.
Liver cirrhosis is a predominant risk factor for hepatocellular carcinoma (HCC). However, the mechanism underlying the progression from cirrhosis to HCC remains unclear. Herein we report the ...concurrent increase of liver progenitor cells (LPCs) and transforming growth factor‐β (TGF‐β) in diethylnitrosamine (DEN)‐induced rat hepatocarcinogenesis and cirrhotic livers of HCC patients. Using several experimental approaches, including 2‐acetylaminofluorene/partial hepatectomy (2‐AAF/PHx) and 3,5‐diethoxycarbonyl‐1,4‐dihydrocollidine (DDC)‐elicited murine liver regeneration, we found that activation of LPCs in the absence of TGF‐β induction was insufficient to trigger hepatocarcinogenesis. Moreover, a small fraction of LPCs was detected to coexpress tumor initiating cell (T‐IC) markers during rat hepatocarcinogenesis and in human HCCs, and TGF‐β levels were positively correlated with T‐IC marker expression, which indicates a role of TGF‐β in T‐IC generation. Rat pluripotent LPC‐like WB‐F344 cells were exposed to low doses of TGF‐β for 18 weeks imitating the enhanced TGF‐β expression in cirrhotic liver. Interestingly, long‐term treatment of TGF‐β on WB‐F344 cells impaired their LPC potential but granted them T‐IC properties including expression of T‐IC markers, increased self‐renewal capacity, stronger chemoresistance, and tumorigenicity in NOD‐SCID mice. Hyperactivation of Akt but not Notch, signal transducer and activator of transcription 3 (STAT3), or mammalian target of rapamycin (mTOR) was detected in TGF‐β‐treated WB‐F344 cells. Introduction of the dominant‐negative mutant of Akt significantly attenuated T‐IC properties of those transformed WB‐F344 cells, indicating Akt was required in TGF‐β‐mediated‐generation of hepatic T‐ICs. We further demonstrate that TGF‐β‐induced Akt activation and LPC transformation was mediated by microRNA‐216a‐modulated phosphatase and tensin homolog deleted on chromosome 10 (PTEN) suppression. Conclusion: Hepatoma‐initiating cells may derive from hepatic progenitor cells exposed to chronic and constant TGF‐β stimulation in cirrhotic liver, and pharmaceutical inhibition of microRNA‐216a/PTEN/Akt signaling could be a novel strategy for HCC prevention and therapy targeting hepatic T‐ICs. (HEPATOLOGY 2012;56:2255–2267)
Autophagy participates in the progression of hepatocellular carcinoma (HCC) and the resistance of HCC cells to sorafenib. We investigated the feasibility of sensitising HCC cells to sorafenib by ...modulating miR-541-initiated microRNA-autophagy axis.
Gain- and loss-of-function assays were performed to evaluate the effects of miR-541 on the malignant properties and autophagy of human HCC cells. Autophagy was quantified by western blotting of LC3, transmission electron microscopy analyses and confocal microscopy scanning of mRFP-GFP-LC3 reporter construct. Luciferase reporter assays were conducted to confirm the targets of miR-541. HCC xenograft tumours were established to analyse the role of miR-541 in sorafenib-induced lethality.
The expression of miR-541 was downregulated in human HCC tissues and was associated with malignant clinicopathologic phenotypes, recurrence and survival of patients with HCC. miR-541 inhibited the growth, metastasis and autophagy of HCC cells both in vitro and in vivo. Prediction software and luciferase reporter assays identified autophagy-related gene 2A (ATG2A) and Ras-related protein Rab-1B (RAB1B) as the direct targets of miR-541. Consistent with the effects of the miR-541 mimic, inhibition of ATG2A or RAB1B suppressed the malignant phenotypes and autophagy of HCC cells. Furthermore, siATG2A and siRAB1B partially reversed the enhancement of the malignant properties and autophagy in HCC cells mediated by the miR-541 inhibitor. More interestingly, higher miR-541 expression predicted a better response to sorafenib treatment, and the combination of miR-541 and sorafenib further suppressed the growth of HCC cells in vivo compared with the single treatment.
Dysregulation of miR-541-ATG2A/RAB1B axis plays a critical role in patients' responses to sorafenib treatment. Manipulation of this axis might benefit survival of patients with HCC, especially in the context of the highly pursued strategies to eliminate drug resistance.
Patients with decompensated cirrhosis face poor prognosis and increased mortality risk. Rifaximin, a non-absorbable antibiotic, has been shown to have beneficial effects in preventing complications ...and improving survival in these patients. However, the underlying mechanisms of rifaximin's effects remain unclear.
We obtained fecal samples from decompensated cirrhotic patients undergoing rifaximin treatment and controls, both at baseline and after 6 months of treatment. Shotgun metagenome sequencing profiled the gut microbiome, and untargeted metabolomics analyzed fecal metabolites. Linear discriminant and partial least squares discrimination analyses were used to identify differing species and metabolites between rifaximin-treated patients and controls.
Forty-two patients were enrolled and divided into two groups (26 patients in the rifaximin group and 16 patients in the control group). The gut microbiome's beta diversity changed in the rifaximin group but remained unaffected in the control group. We observed 44 species with reduced abundance in the rifaximin group, including Streptococcus_salivarius, Streptococcus_vestibularis, Haemophilus_parainfluenzae, etc. compared to only four in the control group. Additionally, six species were enriched in the rifaximin group, including Eubacterium_sp._CAG:248, Prevotella_sp._CAG:604, etc., and 14 in the control group. Furthermore, rifaximin modulated different microbial functions compared to the control. Seventeen microbiome-related metabolites were altered due to rifaximin, while six were altered in the control group.
Our study revealed distinct microbiome-metabolite networks regulated by rifaximin intervention in patients with decompensated cirrhosis. These findings suggest that targeting these specific metabolites or related bacteria might be a potential therapeutic strategy for decompensated cirrhosis.
Drug‐induced liver injury (DILI) is a liver toxicity induced by a drug or its metabolite. The incidence of DILI continues to increase and it has been an enormous challenge worldwide, while the ...prognosis is not optimistic. Currently, the most effective treatment for DILI is to suspend the offending drug(s) and to avoid re‐exposure, with no definitive therapy available for idiosyncratic DILI with or without acute liver failure. Given the anti‐inflammatory effects of corticosteroids, they have been widely used in DILI in clinical practice, although their efficacy remains controversial. Several studies have shown their beneficial effects but a few reports have refuted the efficacy of corticosteroids in treating patients with DILI. In this review, we summarized the history and current status of corticosteroid use in liver diseases and the pros and cons of corticosteroid treatment in DILI, and we explored the DILI candidates who may benefit from corticosteroid therapy, the administration route and dosage, and the adverse effects related to corticosteroid use.
Background
The use of a colonic stent as a bridge to surgery aims to provide patients with elective one-stage surgical resection while reducing stoma creation and postoperative complications. This ...study used meta-analytic techniques to compare the outcomes of stent use as a bridge to surgery and emergency surgery in the management of obstructive colorectal cancer.
Methods
A literature search of Medline, Embase, Cochrane controlled trials registry, and the Chinese Biomedical Literature Database was performed on all studies comparing stent as a bridge to surgery and emergency surgery for obstructive colorectal cancer. A meta-analysis of the included studies was carried out to identify the differences in outcomes between the two procedures.
Results
Eight studies matched the criteria for inclusion and reported on the outcomes of 601 patients, of whom 232 (38.6%) underwent stent insertion and 369 (61.4%) underwent emergency surgery. Fewer patients in the stent group needed intensive care (risk ratio RR, 0.42; 95% confidence interval CI, 0.19–0.93;
p
= 0.03) and stoma creation (RR, 0.70; 95% CI, 0.50–0.99;
p
= 0.04). The primary anastomosis rate in the stent group was higher (RR, 1.62; 95% CI, 1.21–2.16;
p
= 0.001). Overall complications (RR, 0.42; 95% CI, 0.24–0.71;
p
= 0.001), including anastomotic leakage (RR, 0.31; 95% CI, 0.14–0.69;
p
= 0.004), were reduced by stent insertion. Stent placement before elective surgery did not adversely affect mortality and long-term survival.
Conclusions
The use of a stent as a bridge to surgery for obstructive left-sided colorectal cancer could increase the chance of primary anastomosis and reduce the need for stoma creation and postprocedural complications. Stent insertion before subsequent surgery has no effect on perioperative mortality and long-term survival.
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