[A case of interstitial lung and liver disease caused by MARS1 gene mutation]

The patient is a female infant, 4 months and 9 days old, who was admitted to the hospital due to recurrent fever, cough, and hepatomegaly for over a month. The patient was a healthy full-term infant with a normal birth history. At 2 months and 22 days after birth, she developed recurrent fever, cough, and respiratory distress. Chest imaging revealed diffuse bilateral lung lesions, and fiberoptic bronchoscopy showed interstitial changes in both lungs. These suggested the presence of interstitial lung disease. The patient also presented with hepatomegaly, anemia, hyperlipidemia, hypothyroidism, and malnutrition. Genetic testing indicated compound heterozygous variations in the MARS1 gene. This mutation can cause interstitial lung and liver disease, which is a severe rare disorder that typically manifests in infancy or early childhood. It is inherited in an autosomal recessive manner and characterized by early-onset respiratory insufficiency and liver disease in infants or young children. Since its first reported case in 2013, as of June 2023, only 38 related cases have been reported worldwide. This article reports the multidisciplinary diagnosis and treatment of interstitial lung and liver disease in an infant caused by MARS1 gene mutation.

[A multi-center observation of the therapeutic efficacy of Bencycloquidium bromide in the treatment of seasonal allergic rhinitis with predominant symptoms of rhinorrhea]

Objective:To observe the efficacy and safety of the M receptor antagonist Bencycloquidium bromide nasal spray in treatment of seasonal allergic rhinitis with runny nose as the main symptom. Methods:From August 2021 to September 2021, 134 patients with seasonal allergic rhinitis were enrolled in the otolaryngology Outpatient Department of Peking University Third Hospital, First Affiliated Hospital of Harbin Medical University and China-Japanese Friendship Hospital of Jilin University, including 71 males and 63 females, with a median age of 38 years. TNSS score and visual analogue scale（VAS） of total nasal symptoms were observed during 2 weeks of treatment with Bencycloquidium bromide nasal spray. Results:TNSS score decreased from （8.89±3.31） on day 0 to （3.71±2.51） on day 14（P<0.001）, VAS score of nasal symptoms decreased from （24.86±7.40） on day 0 to （6.84±5.94） on day 14（P<0.001）, VAS score of rhinorrhoea decreased from （6.88±2.06） on day 0 to （1.91±1.81） on day 14（P<0.001）. Rhinoconjunctivitis quality of life questionnaire（RQLQ） score decreased from （94.63±33.35） on day 0 to （44.95±32.28） on day 14（P<0.001）. The incidence of adverse reaction was low and no serious adverse events occurred during the whole experiment. Conclusion:Bencycloquidium bromide nasal spray has significant efficacy and good safety in the treatment of seasonal allergic rhinitis.

[Construction and identification of a HEK293 cell line with stable TrxR1 overexpression]

OBJECTIVE

To construct a HEK293 cell line stably overexpressing TrxR1 as a cell model for functional study of TrxR1 and screening of TrxR1-targeting drugs.

METHODS

TrxR1 gene was amplified by PCR and ligated with the lentivirus expression vector pLVX-Puro, which was transformed into Escherichia coli and identified by Sanger dideoxy sequencing. HEK293 cells were infected with the recombinant lentivirus vector (pLVX-Puro-TXNRD1) and screened with Puromycin for cell clones with stable TrxR1 overexpression (HEK293-TrxR1-OE cells). HEK293-TrxR1-OE cells, along with HEK293 cells infected with pLVX-Puro vector (HEK293-NC) and normal HEK293 cells, were tested for mRNA and protein expression levels of TrxR1 using RT-qPCR and Western blotting. TrxR1 enzyme activity in the cells was evaluated with insulin endpoint assay and TRFS-green probe imaging. The sensitivity of the cells to auranofin, a specific TrxR1 inhibitor, was determined with CCK8 assay.

RESULTS

TrxR1 gene was successfully inserted into the lentiviral vector pLVX-Puro as confirmed by DNA sequencing. The enzyme activity and mRNA and protein expression levels of TrxR1 were significantly higher in HEK293-TrxR1-OE cells than in HEK293 and HEK293-NC cells (P < 0.005). The inhibitory effects of auranofin on proliferation and cellular TrxR1 enzyme activity were significantly attenuated in HEK293-TrxR1-OE cells as compared with HEK293 and HEK293-NC cells (P < 0.005).

CONCLUSION

We successfully obtained a HEK293 cell line with stable TrxR1 overexpression, which shows resistance to auranofin and can be used for screening TrxR1 targeting drugs.