Renal fibroblasts are involved in fibrogenic changes in kidney fibrosis associated with dysfunctional telomeres.

Tubulointerstitial fibrosis associated with chronic kidney disease (CKD) represents a global health care problem. We previously reported that short and dysfunctional telomeres lead to interstitial renal fibrosis; however, the cell-of-origin of kidney fibrosis associated with telomere dysfunction is currently unknown. We induced telomere dysfunction by deleting the Trf1 gene encoding a telomere-binding factor specifically in renal fibroblasts in both short-term and long-term life-long experiments in mice to identify the role of fibroblasts in renal fibrosis. Short-term Trf1 deletion in renal fibroblasts was not sufficient to trigger kidney fibrosis but was sufficient to induce inflammatory responses, ECM deposition, cell cycle arrest, fibrogenesis, and vascular rarefaction. However, long-term persistent deletion of Trf1 in fibroblasts resulted in kidney fibrosis accompanied by an elevated urinary albumin-to-creatinine ratio (uACR) and a decrease in mouse survival. These cellular responses lead to the macrophage-to-myofibroblast transition (MMT), endothelial-to-mesenchymal transition (EndMT), and partial epithelial-to-mesenchymal transition (EMT), ultimately causing kidney fibrosis at the humane endpoint (HEP) when the deletion of Trf1 in fibroblasts is maintained throughout the lifespan of mice. Our findings contribute to a better understanding of the role of dysfunctional telomeres in the onset of the profibrotic alterations that lead to kidney fibrosis.

High serum levels of ustekinumab are associated with better clinical outcomes during maintenance treatment for inflammatory bowel disease.

Background: Ustekinumab (UST) is an effective treatment option in Crohn's disease (CD) and ulcerative colitis (UC). However, it still remains unclear if therapeutic drug monitoring could be helpful to guide clinicians. Objectives: The aim of our study was to analyze the relationship between UST through levels (USTTL) and clinical outcomes in real-world inflammatory bowel disease (IBD) patients. Design: We performed a unicentric retrospective study including patients with IBD under UST treatment with at least one level determination. Methods: The following variables were analyzed at the initiation of UST and at each USTTL measurement: clinical response and remission using the Harvey-Bradshaw Index (HBI) for CD and the Partial Mayo Score (pMayo) for UC; biochemical response and remission using fecal calprotectin and C-reactive protein, among others. Two periods were considered: P1 (time between induction and the first determination of USTTL) and P2 (time between USTTL1 and the second determination of USTTL). Results: We included 125 patients, 117 with CD. In P1, 62.4% of patients were on subcutaneous maintenance, and the median USTTL1 was 3.1 µg/mL (1.6-5.3). In 44.8% of CD patients (48/117), clinical remission was achieved, with USTTL1 significantly higher than those who did not achieve remission (3.7 µg/mL (2.3-5.4) vs 2.3 µg/mL (1.1-5.2); p = 0.04). In the 46 patients with two determinations, statistically significant differences were found between variables in P2 versus P1: clinical remission (73.9% vs 21.7%; p = 0.001); USTTL (7.2 µg/mL (4.7-11.7) vs 3.4 µg/mL (1.9-6.4); p < 0.001), HBI (4 (4-4.3) vs 8 (4-9); p < 0.001), pMayo (1 (1-3.3) vs 4.5 (3-5); p = 0.042), and corticosteroid use (26.1% vs 41.3%; p = 0.024). Receiver-Operating-Characteristic (ROC) curves were calculated for clinical remission in P2, with USTTL cutoff value of 6.34 µg/mL for clinical remission and a high rate of intensified patients (98%). Conclusion: High serum levels of UST were associated with clinical remission during treatment for IBD under intensification treatment, with a cutoff point of 6.3 µg/mL.

[Role of diet in the prevention and development of Crohn's Disease]. / Papel de la dieta en la prevención y el desarrollo de la enfermedad de Crohn.

Introduction: Crohn's disease (CD) is a chronic recurrent inflammatory bowel disease (IBD) with frequent ileocolic location, although it can affect the entire gastrointestinal tract. It is characterized by the development of skipped lesions and transmural inflammation and its incidence is increasing. The etiology and pathogenesis are related to genetic susceptibility, intestinal microbiota, dysbiosis, immunological abnormalities and environmental factors (tobacco use, NSAIDs, oral contraceptives and diet). Diet may play a key role in the development and prevention of CD. Dietary patterns with high inflammatory potential (high intake of saturated fat, sugars, proteins, salt, as well as low consumption of fruits and vegetables) are associated with a higher risk of CD, while the consumption of a healthy diet, together with the practice of Exercise is a protective factor against relapses in IBD and reduces the risk of CD. Regarding dietary components, the consumption of fiber, as well as dietary polyphenols, has been related to the maintenance of the intestinal barrier by preventing erosion of the mucosal layer. ω-3 fatty acids, in addition to their anti-inflammatory activity, promote the balance of the intestinal microbiota and their supplementation reduces postoperative complications and accelerates recovery in patients with CD. Vitamin D also plays an important role in the integrity of the intestinal barrier by reducing permeability, in addition to having an immunomodulatory and anti-inflammatory effect, being a useful tool in the improvement of patients with CD. Prebiotics and probiotics may be useful in the treatment of IBD patients by stimulating mucus production, reducing inflammation and dysbiosis, and maintaining the integrity of the intestinal barrier.

Introducción: La enfermedad de Crohn (EC) es una enfermedad inflamatoria intestinal (EII) crónica recurrente con localización frecuente ileocólica, aunque puede afectar a todo el tracto gastrointestinal. Se caracteriza por el desarrollo de lesiones salteadas e inflamación transmural y su incidencia es cada vez mayor. La etiología y la patogénesis está relacionada con la susceptibilidad genética, la microbiota intestinal, la disbiosis, anomalías inmunológicas y factores ambientales (consumo de tabaco, AINE, anticonceptivos orales y la dieta). La dieta puede tener un papel clave en el desarrollo y en la prevención de la EC. Los patrones dietéticos con alto potencial inflamatorio (elevada ingesta de grasa saturada, azúcares, proteínas y sal, así como bajo consumo de frutas y verduras) se asocian con mayor riesgo de EC, mientras que el consumo de una dieta saludable, unida a la práctica de ejercicio, es un factor protector frente a recaídas en EII y disminuye el riesgo de EC. Respecto a los componentes alimentarios, el consumo de fibra, así como de polifenoles dietéticos, se ha relacionado con el mantenimiento de la barrera intestinal al prevenir la erosión de la capa mucosa. Los ácidos grasos ω-3, además de su actividad antiinflamatoria, favorecen el equilibrio de la microbiota intestinal y su suplementación disminuye las complicaciones posoperatorias y acelera la recuperación en pacientes con EC. También la vitamina D desempeña un papel importante en la integridad de la barrera intestinal al disminuir la permeabilidad, además de presentar un efecto inmunomodulador y antiinflamatorio. Es una herramienta útil en la mejora del paciente con EC. Los prebióticos y los probióticos pueden ser útiles en el tratamiento de pacientes con EII al estimular la producción de moco, reducir la inflamación y disbiosis y mantener la integridad de la barrera intestinal.

Cognitive functioning and falls in older people: A systematic review and meta-analysis.

OBJECTIVE: To identify which cognitive functions and specific neuropsychological assessments predict falls in older people living in the community. METHODS: Five electronic databases were searched until 30/08/2022 for studies assessing the association between specific cognitive functions and faller status (prospective and retrospective), in community-dwelling older people. Risk of bias was assessed with the Newcastle-Ottawa Scale. Meta-analyses synthesised the evidence regarding the associations between different neurocognitive subdomains and faller status. RESULTS: Thirty-eight studies (20 retrospective, 18 prospective) involving 37,101 participants were included. All but one study was rated high or medium quality. Meta-analyses were performed with data from 28 studies across 11 neurocognitive subdomains and four specific neuropsychological tests. Poor cognitive flexibility, processing speed, free recall, working memory and sustained attention were significantly associated with faller status, but poor verbal fluency, visual perception, recognition memory, visuo-constructional reasoning and language were not. The Trail Making Test B was found to have the strongest association with faller status. CONCLUSION: Poor performance in neurocognitive subdomains spanning processing speed, attention, executive function and aspects of memory are associated with falls in older people, albeit with small effect sizes. The Trail Making Test, a free-to-use, simple assessment of processing speed and mental flexibility, is recommended as the cognitive screening test for fall risk in older people.

Loss of Lkb1 cooperates with BrafV600E and ultraviolet radiation, increasing melanoma multiplicity and neural-like dedifferentiation.

The mechanisms that work alongside BRAFV600E oncogene in melanoma development, in addition to ultraviolet (UV) radiation (UVR), are of great interest. Analysis of human melanoma tumors [data from The Cancer Genome Atlas (TCGA)] revealed that 50% or more of the samples expressed no or low amounts of serine/threonine protein kinase STK11 (also known as LKB1) protein. Here, we report that, in a mouse model, concomitant neonatal BrafV600E activation and Lkb1 tumor suppressor ablation in melanocytes led to full melanoma development. A single postnatal dose of UVB radiation had no effect on melanoma onset in Lkb1-depleted mice compared with BrafV600E-irradiated mice, but increased tumor multiplicity. In concordance with these findings and previous reports, Lkb1-null irradiated mice exhibited deficient DNA damage repair (DDR). Histologically, tumors lacking Lkb1 were enriched in neural-like tumor morphology. Genetic profiling and gene set enrichment analyses of tumor sample mutated genes indicated that loss of Lkb1 promoted the selection of altered genes associated with neural differentiation processes. Thus, these results suggest that the loss of Lkb1 cooperates with BrafV600E and UVR, impairing the DDR and increasing melanoma multiplicity and neural-like dedifferentiation.

Impact of combined intermittent fasting and high-intensity interval training on apoptosis and atrophy signaling in rat fast- and slow-twitch muscles.

This study aimed to evaluate the influence of combined intermittent fasting (IF) and high-intensity interval training (HIIT) on morphology, caspase-independent apoptosis signaling pathway, and myostatin expression in soleus and gastrocnemius (white portion) muscles from healthy rats. Sixty-day-old male Wistar rats (n = 60) were divided into four groups: control (C), IF, high-intensity-interval training (T), and high-intensity-interval training and intermittent fasting (T-IF). The C and T groups received ad libitum chow daily; IF and T-IF received the same standard chow every other day. Animals from T and T-IF underwent a HIIT protocol five times a week for 12 weeks. IF reduced gastrocnemius mass and increased pro-apoptotic proteins apoptosis-inducing factor (AIF) and endonuclease G (EndoG) in soleus and cleaved-to-non-cleaved PARP-1 ratio and myostatin expression in gastrocnemius white portion. HIIT increased AIF and apoptosis repressor with caspase recruitment domain expression in soleus and cleaved-to-total PARP-1 ratio in gastrocnemius muscle white portion. The combination of IF and HIIT reduced fiber cross-sectional area in both muscles, increased EndoG and AIF expression, and decreased cleaved-to-non-cleaved PARP-1 ratio in gastrocnemius muscle white portion. Muscle responses to IF and HIIT are directly impacted by the muscle fiber type composition and are modulated, at least in part, by myostatin and caspase-independent apoptosis signaling.

Molecular screening of transitional B cells as a prognostic marker of improved graft outcome and reduced rejection risk in kidney transplant.

Introduction: Understanding immune cell dynamics in kidney transplantation may provide insight into the mechanisms of rejection and improve patient management. B cells have gained interest with a special relevance of the "regulatory" subsets and their graft outcome prognostic value. In this study, we aimed to prove that the direct immunophenotyping and target gene expression analysis of kidney transplant patients' fresh whole blood will help to identify graft rejection risk and assist in the monitoring of kidney transplanted patients. Methods: We employed flow cytometry and qPCR techniques to characterize B and T cell subsets within fresh whole blood samples, with particular emphasis on transitional B cells (TrB) identified as CD19+CD24hiCD38hi. TrB are a relevant population in the context of kidney transplantation and are closely associated with regulatory B cells (Bregs) in humans. Patients were monitored, tracking pertinent clinical parameters and kidney-related events, including alterations in graft function and episodes of biopsy proven rejection. Results: Higher percentages of TrB cells at 3 months after transplantation were positively associated with better graft outcomes and lower biopsy-proven acute rejection risk. Furthermore, a novel panel of B cell regulatory associated genes was validated at 3 months post-transplantation by qPCR analysis of peripheral blood mononuclear cell (PBMC) mRNA, showing high predictive power of graft events and prognostic value. Discussion: These findings suggest that monitoring TrB may provide interesting patient management information, improve transplant outcomes, and allow for personalized drug regimens to minimize clinical complications.

The Urinary Glycopeptide Profile Differentiates Early Cardiorenal Risk in Subjects Not Meeting Criteria for Chronic Kidney Disease.

Early diagnosis and treatment of chronic kidney disease (CKD) is a worldwide challenge. Subjects with albumin-to-creatinine ratio (ACR) ≥ 30 mg/g and preserved renal function are considered to be at no cardiorenal risk in clinical practice, but prospective clinical studies evidence increased risk, even at the high-normal (HN) ACR range (10-30 mg/g), supporting the need to identify other molecular indicators for early assessment of patients at higher risk. Following our previous studies, here we aim to stratify the normoalbuminuria range according to cardiorenal risk and identify the glycoproteins and N-glycosylation sites associated with kidney damage in subclinical CKD. Glycoproteins were analyzed in urine from hypertensive patients within the HN ACR range compared to control group (C; ACR < 10 mg/g) by mass spectrometry. A different cohort was analyzed for confirmation (ELISA) and sex perspective was evaluated. Patients' follow-up for 8 years since basal urine collection revealed higher renal function decline and ACR progression for HN patients. Differential N-glycopeptides and their N -glycosylation sites were also identified, together with their pathogenicity. N-glycosylation may condition pathological protein deregulation, and a panel of 62 glycoproteins evidenced alteration in normoalbuminuric subjects within the HN range. Haptoglobin-related protein, haptoglobin, afamin, transferrin, and immunoglobulin heavy constant gamma 1 (IGHG1) and 2 (IGHG2) showed increased levels in HN patients, pointing to disturbed iron metabolism and tubular reabsorption and supporting the tubule as a target of interest in the early progression of CKD. When analyzed separately, haptoglobin, afamin, transferrin, and IGHG2 remained significant in HN, in both women and men. At the peptide level, 172 N-glycopeptides showed differential abundance in HN patients, and 26 showed high pathogenicity, 10 of them belonging to glycoproteins that do not show variation between HN and C groups. This study highlights the value of glycosylation in subjects not meeting KDIGO criteria for CKD. The identified N-glycopeptides and glycosylation sites showed novel targets, for both the early assessment of individual cardiorenal risk and for intervention aimed at anticipating CKD progression.

Exercise, mTOR Activation, and Potential Impacts on the Liver in Rodents.

The literature offers a consensus on the association between exercise training (ET) protocols based on the adequate parameters of intensity and frequency, and several adaptive alterations in the liver. Indeed, regular ET can reverse glucose and lipid metabolism disorders, especially from aerobic modalities, which can decrease intrahepatic fat formation. In terms of molecular mechanisms, the regulation of hepatic fat formation would be directly related to the modulation of the mechanistic target of rapamycin (mTOR), which would be stimulated by insulin signaling and Akt activation, from the following three different primary signaling pathways: (I) growth factor, (II) energy/ATP-sensitive, and (III) amino acid-sensitive signaling pathways, respectively. Hyperactivation of the Akt/mTORC1 pathway induces lipogenesis by regulating the action of sterol regulatory element binding protein-1 (SREBP-1). Exercise training interventions have been associated with multiple metabolic and tissue benefits. However, it is worth highlighting that the mTOR signaling in the liver in response to exercise interventions remains unclear. Hepatic adaptive alterations seem to be most outstanding when sustained by chronic interventions or high-intensity exercise protocols.