Cellular pathways such as inflammation or oxidative stress are the cause and triggers of disease-related malnutrition (DRM), but the influence of these markers on endoplasmic reticulum (ER) stress is unknown. The objective of this study was to analyze the relationship between mitochondrial function and ER stress parameters in a DRM population. The study population was composed of 82 outpatient subjects, of whom 45 were diagnosed with DRM and 37 were confirmed to be normonourished according to the American Society for Parenteral and Enteral Nutrition ASPEN criteria. We evaluated anthropometrical and biochemical parameters, pro-inflammatory cytokines in serum. Oxidative and ER stress markers were analyzed in leukocytes. DRM patients showed significant reductions in albumin and transferrin concerning the normonourished group, and also displayed higher levels of hsCRP, IL6, and TNFα, and the soluble adhesion molecules VCAM-1 and ICAM-1. Besides, oxygen consumption and mitochondrial membrane potential were reduced and Radical Oxygen Species ROS production was enhanced in DRM patients. In the case of ER markers, protein and mRNA expression revealed that CHOP, ATF6, and the P-eIF2α signal were enhanced in malnourished patients compared to control subjects. Correlation studies supported a relationship between weight loss and increased inflammation, mitochondrial dysfunction, and compromised function of the ER. Our results demonstrate that ER stress signaling pathways are influenced by inflammation and mitochondrial function in the leukocytes of a DRM population.

Se expone el caso de un varón de 47 años con carcinoma epidermoide mandibular. Su evolución ocasiona la aparición de una desnutrición calórica severa que requiere una valoración nutricional completa con el método SENPE-SEDOM. Dicha situación se agrava con el tratamiento quirúrgico y oncológico, desarrollando una disfagia mecánica grave, valorada y diagnosticada con el Método de Exploración Clínica Volumen-Viscosidad (MECV-V). El paciente requiere progresivas adaptaciones dietéticas tanto de textura como de aporte nutricional, precisando el uso de sonda de alimentación por gastrostomía y de nutrición enteral a través de ella. La finalidad es mejorar el estado nutricional, que había empeorado como consecuencia de la enfermedad, de los tratamientos y de incorrectas indicaciones nutricionales por personal no experto en nutrición. Al finalizar el tratamiento oncológico, se produce una mejoría de la disfagia, y se modifica la intervención dietética y nutricional, por lo que se progresa de vía enteral a oral con nueva adaptación de textura y con suplementos dietético-nutricionales que permitan la recuperación del estado nutricional, manteniendo la sonda de alimentación por gastrostomía hasta que el paciente se encuentre libre de enfermedad.

Summary Introduction: The psoas muscle index (PMI) and the skeletal mass index (SMI), as determined by computed tomography (CT), are the reference methods for assessing muscle mass. An alternative method is to measure the area of the rectus femoris muscle using ultrasonography (US).Objective : The objective of this study is twofold: firstly, to assess whether ultrasound imaging of the rectus femoris has an adequate correlation with psoas muscle index (PMI) and skeletal mass index (SMI) measurements obtained from computed tomography (CT) scans of oncosurgical patients at the L3 level; and secondly, to establish a cut-off point for diagnosing low muscle mass using this ultrasound technique. Material and methods: A retrospective cross-sectional observational study was carried out on oncosurgical patients referred to the nutrition consultation of the General University Hospital of Castellón over a four-year period. Malnutrition was diagnosed according to the GLIM criteria, muscle mass was assessed by ultrasound using a Mindray device, and skeletal muscle index (SMI) and appendicular skeletal muscle mass (PMI) were measured by computed tomography at the third lumbar vertebra (L3). Patients lacking a CT scan or with a CT scan performed more than one month after the ultrasound examination were excluded. Results: The study cohort comprised 43 patients (31 males), with a mean age of 64.7 ± 6.72 years, a mean BMI of 23.7 ± 4.31 kg/m², and a mortality rate of 25.6%. Most of the evaluations were conducted post-surgically (65.1%), with a notable prevalence of radical cystectomy and hepatic surgery. A total of 53 ultrasound evaluations were conducted, with an average area of 2.96 cm² [2.47-4.2] and adipose tissue of 0.55 cm [0.1-0.99] *. Additionally, computed tomography (CT) scans were performed to assess skeletal muscle mass (SMM) using the SMI/height method, yielding an average area of 38.4 cm² [31.6- 54.7)The median values for the variables were as follows: 272 [207-390] HU,PMI area of 4.31 m² [3.71-5.94] * and 86 [69-103] * HU density in PMI. All data were expressed as median and interquartile range. The Pearson correlation coefficients between US and SMI/height, SMI/height and PMI/height, and US and PMI/height were 0.70, 0.750, and 0.548, respectively. All these coefficients were statistically significant (p < 0.001). Following the established criteria for low muscle mass for SMI (1) and PMI (2), a ROC curve analysis was conducted on US, with a cutoff point for low muscle mass of 3.6 cm² , AUC 0.770 with 70% and specificity 100%.Respect PMI , the cut-off was 3.29 cm 2 and the area under the curve was 0.609, with a sensitivity of 42.55% and a specificity of 100%. Conclusions: The results of this study indicate that there is a significant correlation between SMI, PMI, and the area in cm² measured by US in the rectus femoris according to the protocol of García-Almeida et al. (3). The positive correlation between ultrasound and computed tomography (CT) imaging in our sample, which yielded comparable results to those reported by (4), suggests that ultrasonography may serve as a viable alternative to CT for the detection of low muscle mass. This study is the first to establish a cutoff point for ultrasonography in comparison to SMI and PMI. Further studies are required, utilising a semi-automatic method to circumvent measurement bias and encompassing a larger patient cohort, in order to detect cutoff points pre- and post-surgery for cystectomy and hepatic surgery, as well as cutoff points by sex.