Beneficial effects of exercise, testosterone, vitamin D, calcium and protein in older men-A randomized clinical trial.

BACKGROUND: Due to increasing older populations worldwide, injuries, disabilities and deaths caused by falls among the elderly represent a growing human and societal problem. We aimed to improve health among men of at least 70 years of age with low-normal to low testosterone and mobility problems by using testosterone undecanoate (TU) injections, progressive strength training, and oral supplements of vitamin D, calcium and protein. METHODS: This was a single-centre, randomized, placebo-controlled, double-blind trial with 148 older men with a median age of 77 (73-81) years, testosterone levels at median 8 (5-9) nmol/L (full range from 1.1 to 12.9 nmol/L) and mobility problems, recruited at University Hospital of Copenhagen, Herlev Hospital, Denmark. Participants were randomized into four arms for 20 weeks: (1) TU therapy (n = 37); (2) progressive resistance training with supplements of calcium, vitamin D and protein (n = 36); (3) both interventions combined (n = 36); or (4) no intervention (n = 39). The main outcome measure was the 30-s chair stand test, due to test performance correlating with the risk of serious fall injuries and lower extremity muscle strength. Outcome measurements were performed at baseline and after 20 weeks. RESULTS: After the intervention, the combination group receiving progressive resistance training, TU and supplements achieved a median score of 13 (11-15) compared to the control group at 10 (0-14) in the 30-s chair stand test (P = 0.003). This median improvement of 3.0 was clinically important. Compared to the control group, participants in the combination group also increased quality of life (P < 0.05) and reduced both tiredness (P < 0.05) and leg fat (P < 0.05) and had higher variability in the RR interval (P < 0.01). The group receiving TU reduced gynoid and leg fat compared to the control group (both P < 0.05). Blood tests improved for several variables, especially in the combination group. There was no statistically significant increase in adverse effects from either the supplements or training. CONCLUSIONS: In men ≥70 years old with low-normal to low testosterone and mobility problems, supplements of testosterone, calcium, vitamin D and protein combined with progressive resistance training improved 30-s chair stand test performance, muscle strength and quality of life. Both tiredness and leg fat were reduced, and RR interval variability was increased. Significant adverse effects were not observed.

Digestion of surfactants does not affect their ability to inhibit P-gp-mediated transport in vitro.

While various non-ionic surfactants at low concentrations have been shown to increase the transport of P-gp substrates in vitro, in vivo studies in rats have shown that a higher surfactant concentration is needed to increase the oral absorption of e.g. the P-gp substrates digoxin and etoposide. The aim of the present study was to investigate if intestinal digestion of surfactants could be the reason for this deviation between in vitro and in vivo data. Therefore, Kolliphor EL, Brij-L23, Labrasol and polysorbate 20 were investigated for their ability to inhibit P-gp and increase digoxin absorption in vitro. Transport studies were performed in Caco-2 cells, while P-gp inhibition and cell viability assays were performed in MDCKII-MDR1 cells. Polysorbate 20, Kolliphor EL and Brij-L23 increased absorptive transport and decreased secretory digoxin transport in Caco-2 cells, whereas only polysorbate 20 and Brij-L23 showed P-gp inhibiting properties in the MDCKII-MDR1 cells. Polysorbate 20 and Brij-L23 were chosen for in vitro digestion prior to transport- or P-gp inhibiting assays. Brij-L23 was not digestible, whereas polysorbate 20 reached a degree of digestion around 40%. Neither of the two surfactants showed any significant difference in their ability to affect absorptive or secretory transport of digoxin after pre-digestion. Furthermore, the P-gp inhibiting effects of polysorbate 20 were not decreased significantly. In conclusion, the mechanism behind the non-ionic surfactant mediated in vitro P-gp inhibition seemed independent of the intestinal digestion and the results presented here did not suggest it to be the cause of the observed discrepancy between in vitro and in vivo.

Aortic Root Dimension Using Transthoracic Echocardiography: Results from the Copenhagen City Heart Study.

Findings regarding the relation between aortic size and risk factors are heterogeneous. This study aimed to generate new insights from a population-based adult cohort on aortic root dimensions and their association with age, anthropometric measures, and cardiac risk factors and evaluate the incidence of acute aortic events. Participants from the fifth examination round of the Copenhagen City Heart study (aged 20 to 98 years) with applicable echocardiograms and no history of aortic disease or valve surgery were included. Aorta diameter was assessed at the annulus, sinus of Valsalva, sinotubular junction, and the tubular part of the ascending aorta. The study population comprised 1,796 men and 2,316 women; mean age: 56.4 ± 17.0 and 56.9 ± 18.1 years, respectively. Men had larger aortic root diameters than women regardless of height indexing (p <0.01). Age, height, weight, systolic and diastolic blood pressure, mean arterial pressure, pulse pressure, hypertension, diabetes, ischemic heart disease, and smoking were positively correlated with aortic sinus diameter in the crude and gender-adjusted analyses. However, after full adjustment, only height, weight, and diastolic blood pressure remained significantly positively correlated with aortic sinus diameter (p <0.001). For systolic blood pressure and pulse pressure, the correlation was inverse (p <0.001). During follow-up (median 5.4 [quartile 1 to quartile 3 4.5 to 6.3] years), the incidence rate of first-time acute aortic events was 13.6 (confidence interval 4.4 to 42.2) per 100,000 person-years. In conclusion, beyond anthropometric measures, age, and gender, diastolic blood pressure was the only cardiac risk factor that was independently correlated with aortic root dimensions. The number of aortic events during follow-up was low.

Hit-to-Lead Identification and Validation of a Triaromatic Pleuromutilin Antibiotic Candidate.

Herein, we report the hit-to-lead identification of a drug-like pleuromutilin conjugate 16, based on a triaromatic hit reported in 2020. The lead arose as the clear candidate from a hit-optimization campaign in which Gram-positive antibacterial activity, solubility, and P-gp affinity were optimized. Conjugate 16 was extensively evaluated for its in vitro ADMET performance which, apart from solubility, was overall on par with lefamulin. This evaluation included Caco-2 cell permeability, plasma protein binding, hERG inhibition, cytotoxicity, metabolism in microsomes and CYP3A4, resistance induction, and time-kill kinetics. Intravenous pharmacokinetics of 16 proved satisfactory in both mice and pigs; however, oral bioavailability was limited likely due to insufficient solubility. The in vivo efficacy was evaluated in mice, systemically infected with Staphylococcus aureus, where 16 showed rapid reduction in blood bacteriaemia. Through our comprehensive studies, lead 16 has emerged as a highly promising and safe antibiotic candidate for the treatment of Gram-positive bacterial infections.

Experiences of older vulnerable people with ischemic heart disease and their peer mentors: A qualitative process evaluation.

AIM: To understand the content and context of a realized peer mentor intervention, and to explore how mentors and mentees experienced the intervention. DESIGN: The study was designed as a qualitative process evaluation of a 24-week peer mentor intervention. METHODS: Semi-structured individual interviews were conducted from November 2021 to May 2022 in a purposeful sample of older vulnerable people with ischemic heart disease, referred to as mentees (n = 13), and their peer mentors (n = 12). Thematic analysis was used to analyse, categorize and interpret interview data. RESULTS: Five themes captured the content and context of the peer mentor intervention as experienced by mentors and mentees. 'Takes one to know one', stressing the importance of the mentor-mentee matching process; 'Varying demand for mentors', illustrating the difficulties in predicting who has the greatest need for mentoring; 'Varying degree of familiarity', describing the mentor-mentee relationship as a continuum from formal mentor to informal friend; 'Putting the patient first', illustrating how mentors support mentees based on their personal experiences of successful recovery while letting the mentee set the pace and goals; and 'Varying view of success', showing how intervention success is perceived differently by mentors and mentees. CONCLUSIONS: The study provides new knowledge on how and under what contextual circumstances a mentor intervention works. These findings are important for the implementation of future peer mentor interventions to achieve successful peer mentor support. IMPLICATIONS AND IMPACT: Non-attendance and drop-out from the cardiac rehabilitation program are prevalent problems among older vulnerable people with cardiovascular disease. This study describes a low-cost peer mentor intervention that can support this group of patients. REPORTING METHOD: Standards for reporting qualitative research (SRQR) guided our study. PATIENT OR PUBLIC CONTRIBUTION: A board of cardiovascular patients have contributed to the development and implementation of the intervention being evaluated.

Structure-based discovery of novel P-glycoprotein inhibitors targeting the nucleotide binding domains.

P-glycoprotein (P-gp), a membrane transport protein overexpressed in certain drug-resistant cancer cells, has been the target of numerous drug discovery projects aimed at overcoming drug resistance in cancer. Most characterized P-gp inhibitors bind at the large hydrophobic drug binding domain (DBD), but none have yet attained regulatory approval. In this study, we explored the potential of designing inhibitors that target the nucleotide binding domains (NBDs), by computationally screening a large library of 2.6 billion synthesizable molecules, using a combination of machine learning-guided molecular docking and molecular dynamics (MD). 14 of the computationally best-scoring molecules were subsequently tested for their ability to inhibit P-gp mediated calcein-AM efflux. In total, five diverse compounds exhibited inhibitory effects in the calcein-AM assay without displaying toxicity. The activity of these compounds was confirmed by their ability to decrease the verapamil-stimulated ATPase activity of P-gp in a subsequent assay. The discovery of these five novel P-gp inhibitors demonstrates the potential of in-silico screening in drug discovery and provides a new stepping point towards future potent P-gp inhibitors.

Patient perspectives and barriers in the treatment of neovascular age-related macular degeneration in Denmark: a qualitative study.

OBJECTIVES: This qualitative study aims to identify patient-reported barriers to treatment for neovascular age-related macular degeneration (nAMD) and investigate their impact on quality of life. DESIGN: Using a qualitative explorative design. SETTING: Semi-structured individual or dyadic interviews were conducted with patients and their relatives. PARTICIPANTS: Twenty-one patients completed the interview, with four of them having a relative present. INTERVENTIONS: Gadamer's hermeneutics guided the epistemological approach, and maximum variation sampling was employed to capture diverse patient experiences. An advisory board consisting of patients, relatives and ophthalmologists ensured the relevance of the study. Thematic analysis was conducted using NVivo software. PRIMARY AND SECONDARY OUTCOME MEASURES: To investigate patient-reported barriers to the recommended treatment for nAMD and impact on quality of life. RESULTS: The study included 21 patients with nAMD, with a median age of 79 years. Five themes emerged: (1) good compliance with intravitreal treatment, (2) the dual role of relatives, (3) treatment commute, (4) hospital barriers, (5) preventive health literacy. CONCLUSION: This study highlights the resilience and adherence of patients with nAMD in Denmark to their treatment despite various barriers. While the therapy may have negative effects on their well-being, patients do not opt out of treatment. These findings underscore the importance of personalised treatment plans that provide, for example, convenient access to care and clear future agreements at the hospital. By adopting more patient-centred approaches, healthcare providers can enhance patient satisfaction and improve treatment adherence, ultimately leading to better patient outcomes and quality of life.

Discovery of neutralizing SARS-CoV-2 antibodies enriched in a unique antigen specific B cell cluster.

Despite development of effective SARS-CoV-2 vaccines, a sub-group of vaccine non-responders depends on therapeutic antibodies or small-molecule drugs in cases of severe disease. However, perpetual viral evolution has required continuous efficacy monitoring as well as exploration of new therapeutic antibodies, to circumvent resistance mutations arising in the viral population. We performed SARS-CoV-2-specific B cell sorting and subsequent single-cell sequencing on material from 15 SARS-CoV-2 convalescent participants. Through screening of 455 monoclonal antibodies for SARS-CoV-2 variant binding and virus neutralization, we identified a cluster of activated B cells highly enriched for SARS-CoV-2 neutralizing antibodies. Epitope binning and Cryo-EM structure analysis identified the majority of neutralizing antibodies having epitopes overlapping with the ACE2 receptor binding motif (class 1 binders). Extensive functional antibody characterization identified two potent neutralizing antibodies, one retaining SARS-CoV-1 neutralizing capability, while both bind major common variants of concern and display prophylactic efficacy in vivo. The transcriptomic signature of activated B cells harboring broadly binding neutralizing antibodies with therapeutic potential identified here, may be a guide in future efforts of rapid therapeutic antibody discovery.

Chronic fatigue syndromes: real illnesses that people can recover from.

The 'Oslo Chronic Fatigue Consortium' consists of researchers and clinicians who question the current narrative that chronic fatigue syndromes, including post-covid conditions, are incurable diseases. Instead, we propose an alternative view, based on research, which offers more hope to patients. Whilst we regard the symptoms of these conditions as real, we propose that they are more likely to reflect the brain's response to a range of biological, psychological, and social factors, rather than a specific disease process. Possible causes include persistent activation of the neurobiological stress response, accompanied by associated changes in immunological, hormonal, cognitive and behavioural domains. We further propose that the symptoms are more likely to persist if they are perceived as threatening, and all activities that are perceived to worsen them are avoided. We also question the idea that the best way to cope with the illness is by prolonged rest, social isolation, and sensory deprivation.Instead, we propose that recovery is often possible if patients are helped to adopt a less threatening understanding of their symptoms and are supported in a gradual return to normal activities. Finally, we call for a much more open and constructive dialogue about these conditions. This dialogue should include a wider range of views, including those of patients who have recovered from them.

Characteristics and Outcomes in Patients With Acute Aortic Dissection: A Nationwide Registry Study.

BACKGROUND: We aimed to describe characteristics and outcomes in a nationwide population of patients with acute type A and type B aortic dissection. METHODS: All patients in Denmark with a first-time diagnosis of acute aortic dissection between 2006 and 2015 were identified by national registries. The main outcomes were in-hospital mortality and long-term survival in hospital survivors. RESULTS: The study population comprised 1157 (68%) patients with type A aortic dissection and 556 (32%) patients with type B aortic dissection, median age of 66 (57-74) years and 70 (61-79) years, respectively. Men accounted for 64%. Median follow-up was 8.9 (6.8-11.5) years. Of patients with type A aortic dissection, 74% were managed surgically, whereas 22% of the patients with type B aortic dissection were managed with surgery or endovascular technique. In-hospital mortality was 27% for type A aortic dissection overall (surgery, 18%; no surgery, 52%) and 16% for type B aortic dissection (surgery or endovascular treatment, 13%; conservative treatment, 17%; P < .001, type A vs type B). Of patients discharged alive, survival was persistently better for type A aortic dissection than for type B aortic dissection (P < .001). Unadjusted 1- and 3-year survival of patients with type A aortic dissection discharged alive was 96% and 91%, respectively, for surgically managed and 88% and 78% without surgery. For type B aortic dissection, the numbers were 89% and 83% for endovascular/surgically managed and 89% and 77% for conservatively managed. CONCLUSIONS: We found higher in-hospital mortality for type A and type B aortic dissection than is reported from referral center registries. Type A aortic dissection had the highest mortality rate during the acute phase, whereas for patients who were discharged alive, the mortality rate was higher for patients with type B aortic dissection.

Free fatty acid receptor 1 stimulates cAMP production and gut hormone secretion through Gq-mediated activation of adenylate cyclase 2.

OBJECTIVE: Free fatty acid receptor 1 (FFAR1) is highly expressed in enteroendocrine cells of the small intestine and pancreatic beta cells, where FFAR1 agonists function as GLP-1 and insulin secretagogues, respectively. Most efficacious are so-called second-generation synthetic agonists such as AM5262, which, in contrast to endogenous long-chain fatty acids are able to signal through both IP3/Ca2+ and cAMP pathways. Whereas IP3 signaling is to be expected for the mainly Gq-coupled FFAR1, the mechanism behind FFAR1-induced cAMP accumulation remains unclear, although originally proposed to be Gs mediated. METHODS AND RESULTS: When stimulated with AM5262, we observe that FFAR1 can activate the majority of the Gα proteins, except - surprisingly - members of the Gs family. AM5262-induced FFAR1-mediated transcriptional activation through cAMP response element (CREB) was blocked by the specific Gq inhibitor, YM253890. Furthermore, in Gq-deficient cells no CREB signal was observed unless Gq or G11 was reintroduced by transfection. By qPCR we determined that adenylate cyclase 2 (Adcy2) was highly expressed and enriched relative to the nine other Adcys in pro-glucagon expressing enteroendocrine cells. Co-transfection with ADCY2 increased the FFAR1-induced cAMP response 4-5-fold in WT HEK293 cells, an effect fully inhibited by YM253890. Moreover, co-transfection with ADCY2 had no effect in Gq-deficient cells without reintroduction of either Gq or G11. Importantly, although both AM5262/FFAR1 and isoproterenol/ß2 adrenergic receptor (ß2AR) induced cAMP production was lost in Gs-deficient cells, only the ß2AR response was rescued by Gs transfection, whereas co-transfection with ADCY2 was required to rescue the FFAR1 cAMP response. In situ hybridization demonstrated a high degree of co-expression of ADCY2 and FFAR1 in enteroendocrine cells throughout the intestine. Finally, in the enteroendocrine STC-1 and GLUTag cell lines AM5262-induced cAMP accumulation and GLP-1 secretion were both blocked by YM253890. CONCLUSIONS: Our results show that Gq signaling is responsible not only for the IP3/Ca2+ but also the cAMP response, which together are required for the highly efficacious hormone secretion induced by second-generation FFAR1 agonists - and that ADCY2 presumably mediates the Gq-driven cAMP response.

Nanobody-mediated complement activation to kill HIV-infected cells.

The complement system which is part of the innate immune response against invading pathogens represents a powerful mechanism for killing of infected cells. Utilizing direct complement recruitment for complement-mediated elimination of HIV-1-infected cells is underexplored. We developed a novel therapeutic modality to direct complement activity to the surface of HIV-1-infected cells. This bispecific complement engager (BiCE) is comprised of a nanobody recruiting the complement-initiating protein C1q, and single-chain variable fragments of broadly neutralizing antibodies (bNAbs) targeting the HIV-1 envelope (Env) protein. Here, we show that two anti-HIV BiCEs targeting the V3 loop and the CD4 binding site, respectively, increase C3 deposition and mediate complement-dependent cytotoxicity (CDC) of HIV-1 Env-expressing Raji cells. Furthermore, anti-HIV BiCEs trigger complement activation on primary CD4 T cells infected with laboratory-adapted HIV-1 strain and facilitates elimination of HIV-1-infected cells over time. In summary, we present a novel approach to direct complement deposition to the surface of HIV-1-infected cells leading to complement-mediated killing of these cells.

Impact of membrane lipid polyunsaturation on dopamine D2 receptor ligand binding and signaling.

Increasing evidence supports a relationship between lipid metabolism and mental health. In particular, the biostatus of polyunsaturated fatty acids (PUFAs) correlates with some symptoms of psychiatric disorders, as well as the efficacy of pharmacological treatments. Recent findings highlight a direct association between brain PUFA levels and dopamine transmission, a major neuromodulatory system implicated in the etiology of psychiatric symptoms. However, the mechanisms underlying this relationship are still unknown. Here we demonstrate that membrane enrichment in the n-3 PUFA docosahexaenoic acid (DHA), potentiates ligand binding to the dopamine D2 receptor (D2R), suggesting that DHA acts as an allosteric modulator of this receptor. Molecular dynamics simulations confirm that DHA has a high preference for interaction with the D2R and show that membrane unsaturation selectively enhances the conformational dynamics of the receptor around its second intracellular loop. We find that membrane unsaturation spares G protein activity but potentiates the recruitment of ß-arrestin in cells. Furthermore, in vivo n-3 PUFA deficiency blunts the behavioral effects of two D2R ligands, quinpirole and aripiprazole. These results highlight the importance of membrane unsaturation for D2R activity and provide a putative mechanism for the ability of PUFAs to enhance antipsychotic efficacy.

Phloretin inhibits glucose transport and reduces inflammation in human retinal pigment epithelial cells.

During age-related macular degeneration (AMD), chronic inflammatory processes, possibly fueled by high glucose levels, cause a breakdown of the retinal pigment epithelium (RPE), leading to vision loss. Phloretin, a natural dihydroxychalcone found in apples, targets several anti-inflammatory signaling pathways and effectively inhibits transporter-mediated glucose uptake. It could potentially prevent inflammation and cell death of RPE cells through either direct regulation of inflammatory signaling pathways or through amelioration of high glucose levels. To test this hypothesis, ARPE-19 cells were incubated with or without phloretin for 1 h before exposure to lipopolysaccharide (LPS). Cell viability and the release of pro-inflammatory cytokines interleukin 6 (IL-6), IL-8 and vascular endothelial growth factor (VEGF) were measured. Glucose uptake was studied using isotope uptake studies. The nuclear levels of nuclear factor erythroid 2-related factor 2 (Nrf2) were determined alongside the phosphorylation levels of mitogen-activated protein kinases. Phloretin pretreatment reduced the LPS-induced release of IL-6 and IL-8 as well as VEGF. Phloretin increased intracellular levels of reactive oxygen species and nuclear translocation of Nrf2. It also inhibited glucose uptake into ARPE-19 cells and the phosphorylation of Jun-activated kinase (JNK). Subsequent studies revealed that Nrf2, but not the inhibition of glucose uptake or JNK phosphorylation, was the main pathway of phloretin's anti-inflammatory activities. Phloretin was robustly anti-inflammatory in RPE cells and reduced IL-8 secretion via activation of Nrf2 but the evaluation of its potential in the treatment or prevention of AMD requires further studies.

Rehospitalisations, repeated aortic surgery, and death in initial survivors of surgery for Stanford type A aortic dissection and the significance of age - a nationwide registry-based cohort study.

AIMS: Describe and compare incidences across age groups of rehospitalization, repeated aortic surgery, and death in patients who survived surgery and hospitalization for type A aortic dissection. METHODS AND RESULTS: From Danish nationwide registries, we identified patients hospitalized with Stanford type A aortic dissections (2006-2018). Survivors of hospitalization and surgery on the ascending aorta and/or aortic arch comprised the study population (n = 606, 36 (38.9%) <60 years old (group I), 194 (32.0%) 60-69 years old (group II), and 176 (29.1%) >69 years old (group III)). During the first year, 62.5% were re-hospitalized and 1.4% underwent repeated aortic surgery with no significant differences across age groups (P = 0.68 and P = 0.39, respectively). Further, 5.9% died (group I: 3.0%, group II: 8.3%, group III: 7.4%, P = 0.04). After 10 years, 8.0% had undergone repeated aortic surgery (group I: 11.5%, group II: 8.5%, group III: 1.6%, P = 0.04) and 10.2% (group I), 17.0% (group II), and 22.2% (group III) had died (P = 0.01). Using multivariable Cox regression analysis, we described long-term outcomes comparing age groups. No age differences were found in one-year outcomes, while age > 69 years compared with age < 60 years was associated with a lower rate of repeated aortic surgery [hazard ratio 0.17, 95% confidence interval (CI) 0.04-0.78] and a higher rate of all-cause mortality (hazard ratio 2.44, 95% CI 1.37-4.34) in the 10-year analyses. CONCLUSION: Rehospitalisations in the first year after discharge were common in all age groups, but survival was high. Repeated aortic surgery was significantly more common among younger than older patients.

Subjective and objective cognitive function in adolescent with chronic fatigue following Epstein-Barr virus infection.

OBJECTIVE: Cognitive difficulties are among the most disruptive and disabling problems reported by chronic fatigue syndrome (CFS) sufferers. Acute Epstein-Barr virus (EBV) infection is a trigger of chronic fatigue (CF) and CFS. The aim of this study was to investigate subjectively reported and objectively measured cognitive functioning in fatigued and non-fatigued adolescents six months after EBV infection. METHODS: A total of 195 adolescents (12-19 years) with acute EBV infection were followed prospectively for six months, after which they were grouped as chronically fatigued (CF+) and non-fatigued (CF-) cases based on questionnaire score; the CF+-group was further subgrouped according to CFS diagnosis. A group of 70 healthy controls was also included. Groups were cross-sectionally compared on objective measures of processing speed, executive functions and memory, and subjective cognitive functioning. RESULTS: There were no group differences regarding objective cognitive measures, but the CF+-group reported significantly (p < 0.001) more cognitive problems (cognitive symptoms sum score = 9.5) compared to the CF--group (cognitive symptoms sum score = 5.3) and the healthy control group (cognitive symptoms sum score = 6.4). The CFS subgroup rated symptoms scores even higher but did not differ on cognitive performance tests. CONCLUSION: Subjective experiences of cognitive difficulties characterize adolescents with CF and CFS six months after acute EBV infection, whereas objective measures of cognitive impairment are inconspicuous.

SNAT2 is responsible for hyperosmotic induced sarcosine and glycine uptake in human prostate PC-3 cells.

Solute carriers (SLC) are important membrane transport proteins in normal and pathophysiological cells. The aim was to identify amino acid SLC(s) responsible for uptake of sarcosine and glycine in prostate cancer cells and investigate the impact hereon of hyperosmotic stress. Uptake of 14C-sarcosine and 3H-glycine was measured in human prostate cancer (PC-3) cells cultured under isosmotic (300 mOsm/kg) and hyperosmotic (500 mOsm/kg) conditions for 24 h. Hyperosmotic culture medium was obtained by supplementing the medium with 200 mM of the trisaccharide raffinose. Amino acid SLC expression was studied using RT-PCR, real-time PCR, and western blotting. siRNA knockdown of SNAT2 was performed. Experiments were conducted in at least 3 independent cell passages. The uptake of Sar and Gly was increased approximately 8-ninefold in PC-3 cells after 24 h hyperosmotic culture. PAT1 mRNA and protein could not be detected, while SNAT2 was upregulated at the mRNA and protein level. Transfection with SNAT2-specific siRNA reduced Vmax of Sar uptake from 2653 ± 38 to 513 ± 38 nmol mg protein-1 min-1, without altering the Km value (3.19 ± 0.13 vs. 3.42 ± 0.71 mM), indicating that SNAT2 is responsible for at least 80% of Sar uptake in hyperosmotic cultured PC-3 cells. SNAT2 is upregulated in hyperosmotic stressed prostate cancer cells and SNAT2 is responsible for cellular sarcosine and glycine uptake in hyperosmotic cultured PC-3 cells. Sar is identified as a substrate for SNAT2, and this has physiological implications for understanding cellular solute transport in prostate cancer cells.

Peer-mentor support for older vulnerable myocardial infarction patients referred to cardiac rehabilitation: single-arm feasibility study.

BACKGROUND: The positive effects of cardiac rehabilitation are well established. However, it has an inherent challenge, namely the low attendance rate among older vulnerable patients, which illustrates the need for effective interventions. Peer mentoring is a low-cost intervention that has the potential to improve cardiac rehabilitation attendance and improve physical and psychological outcomes among older patients. The aim of this study was to test the feasibility and acceptability of a peer-mentor intervention among older vulnerable myocardial infarction patients referred to cardiac rehabilitation. METHODS: The study was conducted as a single-arm feasibility study and designed as a mixed methods intervention study. Patients admitted to a university hospital in Denmark between September 2020 and December 2020 received a 24-week peer-mentor intervention. The feasibility of the intervention was evaluated based on five criteria by Orsmond and Cohn: (a) recruitment capability, (b) data-collection procedures, (c) intervention acceptability, (d) available resources, and (e) participant responses to the intervention. Data were collected through self-administrated questionnaires, closed-ended telephone interviews, semi-structured interviews, and document sheets. RESULTS: Twenty patients were offered the peer-mentor intervention. The intervention proved feasible, with a low dropout rate and high acceptability. However, the original inclusion criteria only involved vulnerable women, and this proved not to be feasible, and were therefore revised to also include vulnerable male patients. Peer mentors (n = 17) were monitored during the intervention period, and the findings indicate that their mentoring role did not cause any harm. The peer-mentor intervention showed signs of effectiveness, as a high rate of cardiac rehabilitation attendance was achieved among patients. Quality of life also increased among patients. This was the case for emotional, physical, and global quality of life measures at 24-week follow-up. CONCLUSION: The peer-mentor intervention is a feasible and acceptable intervention that holds the potential to increase both cardiac rehabilitation attendance and quality of life in older vulnerable patients. This finding paves the way for peer-mentor interventions to be tested in randomized controlled trials, with a view toward reducing inequality in cardiac rehabilitation attendance. However, some of the original study procedures were not feasible, and as such was revised. TRIAL REGISTRATION: The feasibility study was registered at ClinicalTrials.gov ( ClinicalTrials.gov identification number: NCT04507529 ), August 11, 2020.