Rescue of mesangial cells from high glucoseinduced over-proliferation and extracellular matrix secretion by hydrogen sulfide

Abstract Background. Hydrogen sulfide (H 2 S) is considered as the third gasotransmitter after nitric oxide and carbon monoxide. This gas molecule participates in the regulation of renal function. Diabetic nephropathy (DN) is one of the major chronic complications of diabetes. The present study aimed to explore the changes in H 2 S metabolism in the early stage of DN and the effects of H 2 S on cultured rat renal glomerular mesangial cells (MCs). Methods. Cultured rat MCs and streptozotocin (STZ)-induced diabetic rats were used in this study. Expression levels of cystathionine γ-lyase (CSE), transforming growth factor-β1 (TGF-β1) and collagen IV in rat renal cortex and in cultured MCs were determined by quantitative real-time PCR and western blot. Reactive oxygen species (ROS) released from rat MCs was assessed by fluorescent probe assays. MCs proliferation was analyzed by 5′-bromo-2′-deoxyuridine incorporation assay. Results. H 2 S levels in the plasma and renal cortex and the levels of CSE messenger RNA (mRNA) and protein in renal cortex were significantly reduced, while the levels of TGF-β1 and collagen IV increased 3 weeks after STZ injection. Administration of NaHS, a H 2 S donor, reversed the increases in TGF-β1 and collagen IV in diabetic rats. By contrast, NaHS did not alter the TGF-β1 and collagen IV levels in non-diabetic rats. But NaHS lowered the CSE mRNA level in renal cortex. Exposure to high glucose promoted ROS generation and cell proliferation, up-regulated the expression of TGF-β1 and collagen IV but decreased the CSE expression in cultured MCs. Treatment of cultured MCs with NaHS reversed the effect of high glucose. NaHS did not change ROS generation, cell proliferation, TGF-β1 and collagen IV expression in the cells cultured with normal glucose. Reduction of endogenous H 2 S generation by DLpropargylglycine, a CSE inhibitor, produced similar cellular effects as high glucose, including increases in cell proliferation, TGF-β1 and collagen IV expressions and ROS generation. Conclusion. Suppressed CSE-catalyzed endogenous H 2 S production in the kidney by hyperglycemia may play an important role in the pathogenesis of DN

Identification and functional characterization of ABCA4 gene variants in three patients with Stargardt disease or retinitis pigmentosa

IntroductionThe diversity of phenotypes, ranging from inherited retinal dystrophies (such as Stargardt disease 1, cone–rod dystrophy 3, and retinitis pigmentosa 19) to late-onset age-related macular degeneration 2, has been attributed to loss-of-function variants in the ABCA4 gene. In this study, we aimed to identify and analyze potential pathogenic ABCA4 variants in patients with Stargardt disease or retinitis pigmentosa and to explore the impact of an intronic variant (NM_000350.3:c.6386 + 4A>G) on mRNA splicing.MethodsWe enrolled three patients from unrelated families with Stargardt disease or retinitis pigmentosa after comprehensive ophthalmological evaluations were performed. Whole-exome sequencing and Sanger sequencing were applied for mutation screening, focusing on inherited retinal dystrophy-related genes. Additionally, the splicing alteration caused by c.6386 + 4A>G was functionally characterized by a minigene splicing assay.ResultsFive ABCA4 germline variants were detected in three patients: one frameshift, one nonsense, one splicing, and two missense variants. Furthermore, two pathogenic and two likely pathogenic variants and one variant of uncertain significance were determined according to ACMG/AMP and ClinGen sequence variant interpretation (SVI) guidelines. The minigene splicing assay result proved that c.6386 + 4A>G affected the wild-type donor splice-site recognition of intron 46 and yielded a truncated transcript with a 47-bp deletion in exon 46.DiscussionOur study identified two novel ABCA4 variants, expanding the mutational spectrum of the ABCA4 gene in Stargardt disease and retinitis pigmentosa while providing new insights into the molecular pathology of ABCA4 splicing defects

Prognostic Significance of SUVmax Combined With Lactate Dehydrogenase in Advanced Lung Cancer Patients Treated With Immune Checkpoint Inhibitor Plus Chemotherapy: A Retrospective Study

PurposeThis research aims to investigate the predictive capacity of PET/CT quantitative parameters combined with haematological parameters in advanced lung cancer patients treated with immune checkpoint inhibitor (ICI) plus chemotherapy.MethodsA total of 120 patients who underwent 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) were enrolled before therapy. The following parameters were calculated: the maximum, mean, and peak standardized uptake value (SUVmax, SUVmean, and SUVpeak, respectively); total tumour volume (MTV) and total lesion glycolysis (TLG); and whole-body metabolic values (MTVwb, TLGwb, SUVmeanwb, and SUVmaxwb). Lactate dehydrogenase (LDH) levels, absolute neutrophil count, absolute platelet count, albumin levels and derived neutrophil to lymphocyte ratio (dNLR) were also computed. The associations between the variables and therapy outcome (evaluated by iRECIST) were analyzed.ResultsBased on iRECIST, 32 of 120 patients showed iPD, 43 iSD, 36 iPR and 9 iCR. Multivariate analysis found that SUVmax, MTVwb, LDH and absolute platelet count were associated with treatment response (P =0.015, P =0.005, P &amp;lt;0.001 and P =0.015, respectively). Kaplan-Meier survival analyses showed that SUVmax ≥11.42 and LDH ≥245 U/L were associated with shorter OS (P = 0.001 and P = 0.004, respectively). Multivariate Cox regression revealed that SUVmax and LDH alone were not correlated with survival prognosis (p&amp;gt;0.05), but the combination of SUVmax and LDH was independently associated with OS (P=0.015, P=0.001, respectively). The median survival time (MST) for the low (LDH&amp;lt;245 and SUVmax&amp;lt;11.42), intermediate(LDH&amp;lt;245 or SUVmax&amp;lt;11.42), and high(SUVmax≥11.42 and LDH≥245) groups was 24.10 months (95% CI: 19.43 to 28.77), 17.41 months (95% CI: 15.83 to 18.99), and 13.76 months (95% CI: 12.51 to 15.02), respectively.ConclusionThis study identified that SUVmax plus LDH correlated with the survival outcome in patients with advanced lung cancer receiving PD-1/PD-L1 blockade plus chemotherapy.</jats:sec