Postoperative jaundice related to UGT1A1 and ABCB11 gene mutations: A case report and literature review.

BACKGROUND: Patients with obstructive jaundice caused by intrahepatic bile duct stones can be effectively managed by surgery. However, some patients may develop postoperative complications, liver failure, and other life-threatening situations. Here, we report a patient with mutations in the uridine 5'-diphospho-glucuronosyltransferase 1A1 (UGT1A1) and bile salt export pump (adenosine triphosphate-binding cassette subfamily B member 11, ABCB11) genes who presented multiple intrahepatic bile duct stones and cholestasis, and the jaundice of the patient increased after partial hepatectomy. CASE SUMMARY: A 52-year-old male patient admitted to the hospital on October 23, 2021, with a progressive exacerbation of jaundice, was found to have multiple intrahepatic bile duct stones with the diagnoses of obstructive jaundice and acute cholecystitis. Subsequently, the patient underwent left hepatectomy with biliary exploration, stone extraction, T-tube drainage, and cholecystectomy without developing any intraoperative complications. The patient had a dark urine color with worsening jaundice postoperatively and did not respond well to plasma exchange and other symptomatic and supportive treatments. Since the progressive increase in postoperative bilirubin could not be clinically explained with any potential reason, including, if not at all, viral infection, cholangitis, autoimmune liver disease, and other causes, the patient underwent whole-exon screening for any genetic diseases, which surprisingly identified UGT1A1 and ABCB11 gene mutations related to glucuronidation of indirect bilirubin as well as bile acid transport in hepatocytes, respectively. Thus, we hypothesized that postoperative refractory cholestasis might result from UGT1A1 and ABCB11 gene mutations and further recommended liver transplantation to the patient, who eventually declined it and died from liver failure six months later. CONCLUSION: Surgery may aggravate cholestasis in patients with multiple intrahepatic bile duct stones and cholestasis associated with UGT1A1 and ABCB11 gene mutations. A liver transplant may be the best option if active medical treatment fails.

Mitochondrial FAD shortage in SLC25A32 deficiency affects folate-mediated one-carbon metabolism.

The SLC25A32 dysfunction is associated with neural tube defects (NTDs) and exercise intolerance, but very little is known about disease-specific mechanisms due to a paucity of animal models. Here, we generated homozygous (Slc25a32Y174C/Y174C and Slc25a32K235R/K235R) and compound heterozygous (Slc25a32Y174C/K235R) knock-in mice by mimicking the missense mutations identified from our patient. A homozygous knock-out (Slc25a32-/-) mouse was also generated. The Slc25a32K235R/K235R and Slc25a32Y174C/K235R mice presented with mild motor impairment and recapitulated the biochemical disturbances of the patient. While Slc25a32-/- mice die in utero with NTDs. None of the Slc25a32 mutations hindered the mitochondrial uptake of folate. Instead, the mitochondrial uptake of flavin adenine dinucleotide (FAD) was specifically blocked by Slc25a32Y174C/K235R, Slc25a32K235R/K235R, and Slc25a32-/- mutations. A positive correlation between SLC25A32 dysfunction and flavoenzyme deficiency was observed. Besides the flavoenzymes involved in fatty acid ß-oxidation and amino acid metabolism being impaired, Slc25a32-/- embryos also had a subunit of glycine cleavage system-dihydrolipoamide dehydrogenase damaged, resulting in glycine accumulation and glycine derived-formate reduction, which further disturbed folate-mediated one-carbon metabolism, leading to 5-methyltetrahydrofolate shortage and other folate intermediates accumulation. Maternal formate supplementation increased the 5-methyltetrahydrofolate levels and ameliorated the NTDs in Slc25a32-/- embryos. The Slc25a32K235R/K235R and Slc25a32Y174C/K235R mice had no glycine accumulation, but had another formate donor-dimethylglycine accumulated and formate deficiency. Meanwhile, they suffered from the absence of all folate intermediates in mitochondria. Formate supplementation increased the folate amounts, but this effect was not restricted to the Slc25a32 mutant mice only. In summary, we established novel animal models, which enabled us to understand the function of SLC25A32 better and to elucidate the role of SLC25A32 dysfunction in human disease development and progression.

Lentiviral miR30-based RNA interference against heparanase suppresses melanoma metastasis with lower liver and lung toxicity.

AIM: To construct short hairpin RNAs (shRNAs) and miR30-based shRNAs against heparanase (HPSE) to compare their safety and their effects on HPSE down-modulation in vitro and in vivo to develop a more ideal therapeutic RNA interference (RNAi) vector targeting HPSE. METHODS: First, we constructed shRNAs and miR30-based shRNAs against HPSE (HPSE-shRNAs and HPSE-miRNAs) and packed them into lentiviral vectors. Next, we observed the effects of the shRNAs on knockdown for HPSE expression, adhesion, migration and invasion abilities in human malignant melanoma A375 cells in vitro. Furthermore, we compared the effects of the shRNAs on melanoma growth, metastasis and safety in xenograft models. RESULTS: Our data showed that these artificial miRNAs targeting HPSE could be effective RNAi agents mediated by Pol II promoters in vitro and in vivo, although these miRNAs were not more potent than the HPSE-shRNAs. It was noted that obvious lung injuries, rarely revealed previously, as well as hepatotoxicity could be caused by lentivirus-mediated shRNAs (LV shRNAs) rather than lentivirus-mediated miRNAs (LV miRNAs) in vivo. Furthermore, enhanced expression of pro-inflammatory cytokines IL-6 and TGF-ß1 and endogenous mmu-miR-21a-5p were detected in lung tissues of shRNAs groups, whereas the expression of mmu-let-7a-5p, mmu-let-7b-5p and mmu-let-7c-5p were down-regulated. CONCLUSION: These findings suggest that artificial miRNAs display an improved safety profile of lowered lung injury or hepatotoxicity relative to shRNAs in vivo. The mechanism of lung injuries caused by shRNAs may be correlated with changes of endogenous miRNAs in the lung. Our data here increase the flexibility of a miRNA-based RNAi system for functional genomic and gene therapy applications.

[Construction of VEGF gene-targeted small interfering RNA mediated by CMV promoter and its silencing effect].

OBJECTIVE: To construct VEGF gene-targeted small interfering RNA (siRNA) and its expression vector driven by CMV promoter and to investigate its interference effect. METHODS: The VEGF gene-targeted hairpin siRNA was designed, two complementary oligonucleotide strands were synthesized. After annealing, two-strand oligonucleotide was inserted into pDC311-SV40-RC vector, which was then identified by PCR and sequenced. Then human U-2 OS cell line was transfected with the vector using lipofectamine method. Finally, ELISA was performed to evaluate the expression of VEGF protein. RESULTS: PCR-identification of positive clone and sequencing confirmed the vector containing the target siRNA. ELISA showed that compared with the control group, the expression levels of VEGF protein in transfected U-2 OS cells were decreased significantly (P<0.05). CONCLUSION: VEGF gene-targeted siRNA and its vector mediated by CMV promoter were successfully constructed, which can reduce the VEGF protein expression after transfecting.

Matrine inhibits invasiveness and metastasis of human malignant melanoma cell line A375 in vitro.

BACKGROUND: Matrine is a traditional Chinese medicine with significant inhibitory activity against malignant tumors. Its effects on the invasiveness and metastasis of malignant tumors have rarely been reported. AIM: To investigate whether matrine can inhibit the metastasis-related activities of the human malignant melanoma cell line A375 in vitro. METHODS: 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and Annexin-V-fluorescein isothiocyanate/propidium iodide (Annexin-V-FITC/PI) affinity assay were used to examine the effects of matrine on the proliferation and apoptosis induction of A375 cells. The morphologic changes of A375 cells were observed by light and electron microscopy. Semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were performed to evaluate the expression of heparanase mRNA and protein. The effect of matrine on the adhesion ability and invasiveness of treated A375 cells was tested by cell-Matrigel adhesion assay and Matrigel invasion assay, respectively. RESULTS: Matrine showed significant inhibition of the proliferation of A375 cells in a dose- and time-dependent manner. It also induced apoptosis in a dose-dependent manner. Compared with the control group, the levels of heparanase mRNA and protein expression of A375 cells treated with different concentrations of matrine were decreased significantly, as were their adhesion ability and invasiveness. CONCLUSIONS: These findings indicate that matrine inhibits the invasiveness and metastasis of A375 cells in vitro. The mechanisms may be linked to the inhibition of cellular proliferation, induction of apoptosis, and downregulation of heparanase mRNA and protein expression.

Assessment of the utility of the tomato fruit-specific E8 promoter for driving vaccine antigen expression.

To assess the utility of the tomato fruit-specific E8 gene's promoter for driving vaccine antigen expression in plant, the 2.2 kb and 1.1 kb E8 promoters were isolated and sequenced from Lycopersicon esculentum cv. Jinfeng #1. The 1.1 kb promoter was fused to vaccine antigen HBsAg M gene for the transfer to Nicotiana tabacum, and the CaMV 35S promoter was used for comparison. Cholera toxin B (ctb) gene under the control of the 1.1 kb promoter was transformed into both N. tabacum and L. esculentum. Southern blot hybridization confirmed the stable integration of the target genes into the tomato and tobacco genomes. ELISA assay showed that the expression product of HBsAg M gene under the control of the 1.1 kb E8 promoter could not be detected in transgenic tobacco tissues such as leaves, flowers, and seeds. In contrast, the expression of HBsAg M gene driven by CaMV 35S promoter could be detected in transgenic tobacco. ELISA assay for CTB proved that the 1.1 kb E8 promoter was able to direct the expression of exotic gene in ripe fruits of transgenic tomato, but expression was absent in leaf, flower, and unripe fruit of tomato, and CTB protein was not detected in transgenic tobacco tissues such as leaves, flowers, and seeds when the gene was under the control of the 1.1 kb E8 promoter. The results indicated that the E8 promoter acted not only in an organ-specific, but also in a species-specific fashion in plant transformation.

[Inhibition of invasiveness and expression of heparanase-mRNA in human malignant melanoma cell line A375 by matrine].

OBJECTIVE: To investigate the effect of matrine on the invasiveness and expression of heparanase-mRNA in human malignant melanoma cell line A375. METHODS: The A375 cells were treated by matrine in different concentration. The total RNAs were extracted from the cells 48 hours after treatment and then semi-quantitative RT-PCR were performed to evaluate the heparanase-mRNA expression levels. Effect of matrine on adhesion of treated A375 cells was tested by cell-Matrigel adhesion assay. The invasiveness of treated A375 cells was measured by Matrigel invasion assay. RESULTS: The hepanase-mRNA expression, adhesion and invasiveness of A375 cells treated with matrine of different final concentrations significantly decreased compared with that of the controls (p < 0.01). Besides, the inhibitory effects were signifcantly different when the cells treated with matrine of different concentrations (P < 0.01). CONCLUSION: By down-regulating the expression of heparanase-mRNA, matrine has a significant inhibitory effect on the adhesion and invasiveness of human malignant melanoma cell line in a dose-dependent manner.

[Relationship between Shenzhen HBV genotype and precore/core promoter mutation and antiviral effects].

BACKGROUND: To study the relationship between hepatitis B virus genotyping Shenzhen isolates and HBV precore/core promoter mutation and antiviral effects. METHODS: The HBV genotyping of 165 patients with HBV was carried out with mAbs ELISA. HBV precore/core promoter mutation was detected with gene chip technology in 24 patients with CHB. The relationship between HBV genotyping and interferon, lamivudine effects was analyzed. RESULTS: (1) Out of 165 cases, 106 (64.2%) of type B but 48 (29.1%) of type C were found. Type B accounted for 95.4% in group ASC, and type C for 64.7%in group LC (P<0.05). (2) Precore/core promoter mutation was found in 16 cases (10 of type B, and 6 of type C) out of 24 cases. Out of 16 cases, precore/core promoter mutation (nt1896, 1862) was found in 10 cases (9 cases of type B and 1 case of type C), while basal core promoter mutation (BCP mutation, nt1762,1764) was found in 6 cases (1 case of type B and 5 of type C). (3) Among 27 patients with CHB HBAg (+) treated with interferon, 11 cases of type B but 1 case of type C were tested to be fully responsive to interferon. Among 29 patients with CHB HBAg (+) treated with lamivudine, 15 cases of type B but 3 cases of type C were tested to be continuously responsive to lamivudine. CONCLUSION: (1) HBV genotype popularity in Shenzhen area was classified as type B the first and type C the second. (2) Type C seems more apt to develop BCP mutation and cirrhosis, and to be less responsive to interferon or lamivudine.

[Cloning of ACE-2 gene encoding the functional receptor for the SARS coronavirus and its expression in eukaryotic cells].

OBJECTIVE: Angiotensin-converting enzyme 2 (ACE-2) has been identified as a functional receptor of severe acute respiratory syndrome coronavirus (SARS-CoV), so its gene was cloned and eukaryotic expressed for further insight into mechanisms in SARS-CoV entry and pathogenesis, as well as development of a safe and reliable neutralization assay for SARS-CoV. METHODS: Total RNA was extracted from right atrial tissue of a patient with right heart failure resected during a valvular replacement surgery by Trizol one-step method, and the full-length ACE-2 encoding gene was acquired by RT-nested-PCR. The ACE-2 encoding gene was then cloned into pcDNA4/HisMax-TOPO eukaryotic expression vector to construct the recombinant plasmid pcDNA4/ ACE-2, which was then transfected into 293 T cell and ACE-2 eukaryotic transient expression was detected by Western Blot. Syncytia inhibition assay was established to detect SARS-CoV neutralizing antibody, and compared parallelly with SARS pseudovirus neutralization assay. RESULTS: The recombinant plasmid pcDNA4/ ACE-2 could express ACE-2 protein in eukaryotic cells and induce cell-cell fusion between S protein- and ACE2-expressing cells. This cell-cell fusion assay could be used to detect SARS-CoV neutralizing antibody. CONCLUSION: SARS-CoV receptor ACE-2 gene was successfully cloned and eukaryotic expressed, and used to establish syncytia inhibition assay for SARS-CoV neutralizing antibody assay.