Sarcopenia in idiopathic pulmonary fibrosis: a prospective study exploring prevalence, associated factors and diagnostic approach.

BACKGROUND: Sarcopenia gained importance in the evaluation of patients with chronic respiratory diseases, including idiopathic pulmonary fibrosis (IPF), since it may impact negatively on clinical outcomes. AIM: Aim of this study is to evaluate the prevalence and factors associated with sarcopenia, defined according to the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) 2019 definition, and to evaluate the prevalence of the single criteria that define the EWGSOP2 definition (muscle strength, muscle quantity and physical performance), in a cohort of consecutive patients with IPF prospectively followed up in 9 hospitals in Northern Italy between December 2018 and May 2021. METHODS: Enrolled patients underwent an extensive pulmonary and nutritional assessment, including bioelectrical impedance analysis, dynamometry and 4-m gait speed test, both at IPF diagnosis and at 6-month follow-up. RESULTS: Out of the 83 patients (81% males, mean age 72.5 years) with IPF at disease diagnosis enrolled in the study, 19 (22.9%) showed sarcopenia, including 2 (2.4%) with severe sarcopenia, 5 (6.0%) with confirmed sarcopenia and 12 (14.5%) with probable sarcopenia. Sarcopenia was associated with a significantly higher severity of the disease and sedentary lifestyle, while no differences were observed in regards to body mass index, history of weight loss and comorbidities between patients with and without sarcopenia. Out of the 64 patients without sarcopenia at baseline, 16 cases showed alteration of muscle quantity and/or physical performance. In the 51 patients with complete data at 6-month follow-up, there were no cases of severe sarcopenia, 1 case (2.0%) showed confirmed sarcopenia, while the prevalence of probable sarcopenia was 19.6% (10 cases). No differences in regards to antifibrotic treatment received and onset of gastrointestinal side effects were observed between patients with and without sarcopenia at follow-up. CONCLUSIONS: The prevalence of sarcopenia in patients with IPF both at diagnosis and at 6-month follow-up was low but not negligible and was associated with higher severity of the disease and sedentary lifestyle. In IPF patients, a comprehensive diagnostic work-up including all the criteria defining the EWGSOP2 definition might be more useful than a series testing for prompt recognition of nutritional and physical performance abnormalities.

One-year pulmonary impairment after severe COVID-19: a prospective, multicenter follow-up study.

BACKGROUND: Long-term pulmonary sequelae following hospitalization for SARS-CoV-2 pneumonia is largely unclear. The aim of this study was to identify and characterise pulmonary sequelae caused by SARS-CoV-2 pneumonia at 12-month from discharge. METHODS: In this multicentre, prospective, observational study, patients hospitalised for SARS-CoV-2 pneumonia and without prior diagnosis of structural lung diseases were stratified by maximum ventilatory support ("oxygen only", "continuous positive airway pressure (CPAP)" and "invasive mechanical ventilation (IMV)") and followed up at 12 months from discharge. Pulmonary function tests and diffusion capacity for carbon monoxide (DLCO), 6 min walking test, high resolution CT (HRCT) scan, and modified Medical Research Council (mMRC) dyspnea scale were collected. RESULTS: Out of 287 patients hospitalized with SARS-CoV-2 pneumonia and followed up at 1 year, DLCO impairment, mainly of mild entity and improved with respect to the 6-month follow-up, was observed more frequently in the "oxygen only" and "IMV" group (53% and 49% of patients, respectively), compared to 29% in the "CPAP" group. Abnormalities at chest HRCT were found in 46%, 65% and 80% of cases in the "oxygen only", "CPAP" and "IMV" group, respectively. Non-fibrotic interstitial lung abnormalities, in particular reticulations and ground-glass attenuation, were the main finding, while honeycombing was found only in 1% of cases. Older patients and those requiring IMV were at higher risk of developing radiological pulmonary sequelae. Dyspnea evaluated through mMRC scale was reported by 35% of patients with no differences between groups, compared to 29% at 6-month follow-up. CONCLUSION: DLCO alteration and non-fibrotic interstitial lung abnormalities are common after 1 year from hospitalization due to SARS-CoV-2 pneumonia, particularly in older patients requiring higher ventilatory support. Studies with longer follow-ups are needed.

Six-Month Pulmonary Impairment after Severe COVID-19: A Prospective, Multicentre Follow-Up Study.

BACKGROUND: Long-term pulmonary sequelae following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia are not yet confirmed; however, preliminary observations suggest a possible relevant clinical, functional, and radiological impairment. OBJECTIVES: The aim of this study was to identify and characterize pulmonary sequelae caused by SARS-CoV-2 pneumonia at 6-month follow-up. METHODS: In this multicentre, prospective, observational cohort study, patients hospitalized for SARS-CoV-2 pneumonia and without prior diagnosis of structural lung diseases were stratified by maximum ventilatory support ("oxygen only," "continuous positive airway pressure," and "invasive mechanical ventilation") and followed up at 6 months from discharge. Pulmonary function tests and diffusion capacity for carbon monoxide (DLCO), 6-min walking test, chest X-ray, physical examination, and modified Medical Research Council (mMRC) dyspnoea score were collected. RESULTS: Between March and June 2020, 312 patients were enrolled (83, 27% women; median interquartile range age 61.1 [53.4, 69.3] years). The parameters that showed the highest rate of impairment were DLCO and chest X-ray, in 46% and 25% of patients, respectively. However, only a minority of patients reported dyspnoea (31%), defined as mMRC ≥1, or showed restrictive ventilatory defects (9%). In the logistic regression model, having asthma as a comorbidity was associated with DLCO impairment at follow-up, while prophylactic heparin administration during hospitalization appeared as a protective factor. The need for invasive ventilatory support during hospitalization was associated with chest imaging abnormalities. CONCLUSIONS: DLCO and radiological assessment appear to be the most sensitive tools to monitor patients with the coronavirus disease 2019 (COVID-19) during follow-up. Future studies with longer follow-up are warranted to better understand pulmonary sequelae.

Molecular Biomarkers in Idiopathic Pulmonary Fibrosis: State of the Art and Future Directions.

Idiopathic pulmonary fibrosis (IPF), the most lethal form of interstitial pneumonia of unknown cause, is associated with a specific radiological and histopathological pattern (the so-called "usual interstitial pneumonia" pattern) and has a median survival estimated to be between 3 and 5 years after diagnosis. However, evidence shows that IPF has different clinical phenotypes, which are characterized by a variable disease course over time. At present, the natural history of IPF is unpredictable for individual patients, although some genetic factors and circulating biomarkers have been associated with different prognoses. Since in its early stages, IPF may be asymptomatic, leading to a delayed diagnosis. Two drugs, pirfenidone and nintedanib, have been shown to modify the disease course by slowing down the decline in lung function. It is also known that 5-10% of the IPF patients may be affected by episodes of acute and often fatal decline. The acute worsening of disease is sometimes attributed to identifiable conditions, such as pneumonia or heart failure; but many of these events occur without an identifiable cause. These idiopathic acute worsenings are termed acute exacerbations of IPF. To date, clinical biomarkers, diagnostic, prognostic, and theranostic, are not well characterized. However, they could become useful tools helping facilitate diagnoses, monitoring disease progression and treatment efficacy. The aim of this review is to cover molecular mechanisms underlying IPF and research into new clinical biomarkers, to be utilized in diagnosis and prognosis, even in patients treated with antifibrotic drugs.

Snf1/AMPK promotes SBF and MBF-dependent transcription in budding yeast.

Snf1, the yeast AMP-activated kinase homolog, regulates the expression of several genes involved in adaptation to glucose limitation and in response to cellular stresses. We previously demonstrated that Snf1 interacts with Swi6, the regulatory subunit of SBF and MBF complexes, and activates CLB5 transcription. Here we report that, in α-factor synchronized cells in 2% glucose, the loss of the Snf1 catalytic subunit impairs the binding of SBF and MBF complexes and the subsequent recruitment of the FACT complex and RNA Polymerase II to promoters of G1-genes. By using an analog-sensitive allele of SNF1, SNF1(as)(I132G), encoding a protein whose catalytic activity is selectively inhibited in vivo by 2-naphthylmethyl pyrazolopyrimidine 1, we show that the inhibition of Snf1 catalytic activity affects the expression of G1-genes causing a delayed entrance into S phase in cells synchronized in G1 phase by α-factor treatment or by elutriation. Moreover, Snf1 is detected in immune complexes of Rpb1, the large subunit of RNA Polymerase II, and is present at both promoters and coding regions of SBF- and MBF-regulated genes 20min after α-factor release, suggesting a direct role for Snf1 in the activation of the G1-regulon transcription.

Protein kinase CK2 holoenzyme promotes start-specific transcription in Saccharomyces cerevisiae.

In Saccharomyces cerevisiae, the entrance into S phase requires the activation of a specific burst of transcription, which depends on SBF (SCB binding factor, Swi4/Swi6) and MBF (MCB binding factor, Mbp1/Swi6) complexes. CK2 is a pleiotropic kinase involved in several cellular processes, including the regulation of the cell cycle. CK2 is composed of two catalytic subunits (α and α') and two regulatory subunits (ß and ß'), both of which are required to form the active holoenzyme. Here we investigate the function of the CK2 holoenzyme in Start-specific transcription. The ckb1Δ ckb2Δ mutant strain, bearing deletions of both genes encoding CK2 regulatory subunits, shows a delay of S-phase entrance due to a severe reduction of the expression of SBF- and MBF-dependent genes. This transcriptional defect is caused by an impaired recruitment of Swi6 and Swi4 to G1 gene promoters. Moreover, CK2 α and ß' subunits interact with RNA polymerase II, whose binding to G1 promoters is positively regulated by the CK2 holoenzyme. Collectively, these findings suggest a novel role for the CK2 holoenzyme in the activation of G1 transcription.

Impact of N-acetyl-l-cysteine on SARS-CoV-2 pneumonia and its sequelae: results from a large cohort study.

Patients receiving N-acetyl-l-cysteine (NAC) during hospitalisation for #SARSCoV2 pneumonia and discharged alive present a significantly shorter length of hospital stay compared to those who did not receive NAC https://bit.ly/3l1QsVo.

Nutritional assessment in idiopathic pulmonary fibrosis: a prospective multicentre study.

Background: Nutritional status impacts quality of life and prognosis of patients with respiratory diseases, including idiopathic pulmonary fibrosis (IPF). However, there is a lack of studies performing an extensive nutritional assessment of IPF patients. This study aimed to investigate the nutritional status and to identify nutritional phenotypes in a cohort of IPF patients at diagnosis. Methods: Patients underwent a thorough pulmonary and nutritional evaluation including questionnaires on nutritional status, and physical activity, anthropometry, body impedance, dynamometry, 4-m gait speed and blood tests. Results: 90 IPF patients (78.9% males, mean age 72.7 years) were enrolled. The majority of patients were classified as Gender-Age-Physiology Index stage 2 (47, 52.2%) with an inactive lifestyle according to International Physical Activity Questionnaire score (39, 43.3%), and had mean forced vital capacity and diffusing capacity for carbon monoxide 86.5% and 54.2%, respectively. In regards to nutritional phenotypes, the majority of patients were normally nourished (67.8%, 95% CI 58.6-77.7%), followed by non-sarcopenic obese (25.3%, 95% CI 16.1-35.2%), sarcopenic (4.6%, 95% CI 0.0-14.5%) and sarcopenic obese (2.3%, 95% CI 0.0-12.2%). Among the normally nourished, 49.2% showed early signs of nutritional and physical performance alterations, including body mass index ≥30 kg·m-2 in 4.3%, history of weight loss ≥5% in 11.9%, and reduction of gait speed and hand grip strength in 11.9% and 35.6%, respectively. Low vitamin D values were observed in 56.3% of cases. Conclusions: IPF patients at diagnosis are mainly normally nourished and obese, but early signs of nutritional and physical performance impairment can already be identified at this stage.

Rio1 promotes rDNA stability and downregulates RNA polymerase I to ensure rDNA segregation.

The conserved protein kinase Rio1 localizes to the cytoplasm and nucleus of eukaryotic cells. While the roles of Rio1 in the cytoplasm are well characterized, its nuclear function remains unknown. Here we show that nuclear Rio1 promotes rDNA array stability and segregation in Saccharomyces cerevisiae. During rDNA replication in S phase, Rio1 downregulates RNA polymerase I (PolI) and recruits the histone deacetylase Sir2. Both interventions ensure rDNA copy-number homeostasis and prevent the formation of extrachromosomal rDNA circles, which are linked to accelerated ageing in yeast. During anaphase, Rio1 downregulates PolI by targeting its subunit Rpa43, causing PolI to dissociate from the rDNA. By stimulating the processing of PolI-generated transcripts at the rDNA, Rio1 allows for rDNA condensation and segregation in late anaphase. These events finalize the genome transmission process. We identify Rio1 as an essential nucleolar housekeeper that integrates rDNA replication and segregation with ribosome biogenesis.

Snf1/AMPK promotes S-phase entrance by controlling CLB5 transcription in budding yeast.

The Saccharomyces cerevisiae Snf1 protein kinase has been reported to be required for adaptation to glucose limitation and for growth on non-fermentable carbon sources. Here we present novel findings indicating that Snf1, the key regulator of cellular energy, is also involved in yeast cell cycle control. The lack of Snf1 α-catalytic subunit down-regulates the growth rate and CLB5 expression, delaying Sld2 phosphorylation and G 1/S transition, in cells grown in 2%, but not in 5% glucose. A non-phosphorylatable Snf1 rescues the slow growth phenotype, whereas a wild type or a phosphomimetic mutant is required to rescue growth rate and the G 1/S delay. Using either Snf1 or Swi6 as a bait, a specific interaction of Snf1 with Swi6, the regulatory subunit of MBF, was detected. In conclusion, this report describes a previously unrecognized role for Snf1 in transcriptional modulation of the G 1 to S transition, differing from the reported AMPK role in controlling the G 1/S transition in multicellular eukaryotes.