A renal clearable fluorogenic probe for in vivo ß-galactosidase activity detection during aging and senolysis.

Accumulation of senescent cells with age leads to tissue dysfunction and related diseases. Their detection in vivo still constitutes a challenge in aging research. We describe the generation of a fluorogenic probe (sulfonic-Cy7Gal) based on a galactose derivative, to serve as substrate for ß-galactosidase, conjugated to a Cy7 fluorophore modified with sulfonic groups to enhance its ability to diffuse. When administered to male or female mice, ß-galactosidase cleaves the O-glycosidic bond, releasing the fluorophore that is ultimately excreted by the kidneys and can be measured in urine. The intensity of the recovered fluorophore reliably reflects an experimentally controlled load of cellular senescence and correlates with age-associated anxiety during aging and senolytic treatment. Interestingly, our findings with the probe indicate that the effects of senolysis are temporary if the treatment is discontinued. Our strategy may serve as a basis for developing fluorogenic platforms designed for easy longitudinal monitoring of enzymatic activities in biofluids.

Prolonged estrogen deprivation triggers a broad immunosuppressive phenotype in breast cancer cells.

Among others, expression levels of programmed cell death 1 ligand 1 (PD-L1) have been explored as biomarkers of the response to immune checkpoint inhibitors in cancer therapy. Here, we present the results of a chemical screen that interrogated how medically approved drugs influence PD-L1 expression. As expected, corticosteroids and inhibitors of Janus kinases were among the top PD-L1 downregulators. In addition, we identified that PD-L1 expression is induced by antiestrogenic compounds. Transcriptomic analyses indicate that chronic estrogen receptor alpha (ERα) inhibition triggers a broad immunosuppressive program in ER-positive breast cancer cells, which is subsequent to their growth arrest and involves the activation of multiple immune checkpoints together with the silencing of the antigen-presenting machinery. Accordingly, estrogen-deprived MCF7 cells are resistant to T-cell-mediated cell killing, in a manner that is independent of PD-L1, but which is reverted by estradiol. Our study reveals that while antiestrogen therapies efficiently limit the growth of ER-positive breast cancer cells, they concomitantly trigger a transcriptional program that favors their immune evasion.

Rilpivirine attenuates liver fibrosis through selective STAT1-mediated apoptosis in hepatic stellate cells.

OBJECTIVE: Liver fibrosis constitutes a major health problem worldwide due to its rapidly increasing prevalence and the lack of specific and effective treatments. Growing evidence suggests that signalling through cytokine-activated Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathways regulates liver fibrosis and regeneration. Rilpivirine (RPV) is a widely used anti-HIV drug not reported to produce hepatotoxicity. We aimed to describe the potential hepatoprotective effects of RPV in different models of chronic liver injury, focusing on JAK-STAT signalling regulation. DESIGN: The effects of RPV on hepatic steatosis, inflammation and fibrogenesis were studied in a nutritional mouse model of non-alcoholic fatty liver disease, carbon tetrachloride-induced fibrosis and bile duct ligation-induced fibrosis. Primary human hepatic stellate cells (hHSC) and human cell lines LX-2 and Hep3B were used to investigate the underlying molecular mechanisms. RESULTS: RPV exerted a clear anti-inflammatory and antifibrotic effect in all the in vivo models of liver injury employed, and enhanced STAT3-dependent proliferation in hepatocytes and apoptosis in HSC through selective STAT1 activation. These results were reproduced in vitro; RPV undermined STAT3 activation and triggered STAT1-mediated pathways and apoptosis in HSC. Interestingly, this selective pro-apoptotic effect completely disappeared when STAT1 was silenced. Conditioned medium experiments showed that HSC apoptosis activated STAT3 in hepatocytes in an interleukin-6-dependent mechanism. CONCLUSION: RPV ameliorates liver fibrosis through selective STAT1-dependent induction of apoptosis in HSC, which exert paracrinal effects in hepatocytes, thus promoting liver regeneration. RPV's actions may represent an effective strategy to treat chronic liver diseases of different aetiologies and help identify novel therapeutic targets.

SWEPT SOURCE OPTICAL COHERENCE TOMOGRAPHY EVALUATION OF CHORIORETINAL CHANGES IN HYPERTENSIVE CHOROIDOPATHY RELATED TO HELLP SYNDROME.

PURPOSE: To report a case of hypertensive choroidopathy with detailed chorioretinal images obtained using swept source optical coherence tomography. METHODS: We report the case of a 36-year-old pregnant woman who presented with extensive bilateral exudative retinal detachments (visual acuity of hands movement bilaterally), high blood pressure, and severe alteration of the laboratory test results resulting in the diagnosis of HELLP syndrome. The baby was delivered by emergency cesarean section and the patient was hospitalized in the intensive care unit. RESULTS: Two weeks later, exudative retinal detachments improved substantially and bilateral Elschnig spots were present in the posterior fundus. Swept source optical coherence tomography revealed serous retinal detachment, multiple pigmentary epithelial detachments (PEDs), a thickened subfoveal choroid (437 and 466 µm), and fibrinous material between the neurosensory retina and retinal pigment epithelium in the B-scans of both eyes. En face swept source optical coherence tomography allowed a more precise evaluation of the multiple and confluent PEDs. Six weeks later, despite some focal areas of thickened retinal pigment epithelium, the serous retinal detachment, PEDs, and fibrinous material resolved bilaterally and visual acuity and choroidal thickness returned to normal range (361 and 366 µm). En face swept source optical coherence tomography revealed a dramatic improvement of PEDs in terms of extension and distribution. CONCLUSION: Swept source optical coherence tomography detected serous retinal detachment, PEDs, increased subfoveal choroidal thickness, and fibrinous material under the neurosensory retina in the acute phase of hypertensive choroidopathy. En face OCT is useful for monitoring the evolution of confluent PEDs in hypertensive choroidopathy.

PREOPERATIVE VITREORETINAL INTERFACE ABNORMALITIES ON SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY AS RISK FACTOR FOR PSEUDOPHAKIC CYSTOID MACULAR EDEMA AFTER PHACOEMULSIFICATION.

PURPOSE: We assessed the role of vitreoretinal interface status in the development of pseudophakic cystoid macular edema (PCME) after cataract surgery. METHODS: Prospective cohort study in which 112 patients (112 eyes) scheduled for cataract surgery were selected at random to undergo spectral domain optical coherence tomography (OCT) within 1 week preoperatively and at 1 and 3 months postoperatively. Spectral domain OCT macular images included no vitreoretinal contact, focal and diffuse vitreomacular adhesion, focal and diffuse vitreomacular traction, epiretinal membrane, macular hole, and macular edema. RESULTS: The incidence of PCME was 11.6% (13 eyes), all of them being diagnosed at 1 month, and 7 eyes resolved at 3 months. The only risk factor for PCME was detection of nonsurgical epiretinal membrane by spectral domain OCT before phacoemulsification, being developed in 5 of 16 eyes (χ = 0.08, odds ratio 4.53, 95% confidence interval 1.28-16.13). Other variables such as posterior vitreous detachment, subfoveal choroidal thickness, diabetes, or hypertension were not significantly associated with PCME. CONCLUSION: In this cohort, preoperative detection of epiretinal membrane by spectral domain OCT was a risk factor for PCME after cataract extraction. It is recommended to perform a spectral domain OCT before cataract surgery because the presence of an epiretinal membrane may be passed unnoticed by fundus examination.