Neuromuscular electrical stimulation for physical function maintenance during hematopoietic stem cell transplantation: Study protocol.

Hematopoietic stem cell transplantation is a common life-saving treatment for hematologic malignancies, though can lead to long-term functional impairment, fatigue, muscle atrophy, with decreased quality of life. Although traditional exercise has helped reduce these effects, it is inconsistently recommended and infrequently maintained, and most patients remain sedentary during and after treatment. There is need for alternative rehabilitation strategies, like neuromuscular electrical stimulation, that may be more amenable to the capabilities of hematopoietic stem cell transplant recipients. Patients receiving autologous HCT are being enroled in a randomized controlled trial with 1:1 (neuromuscular electrical stimulation:sham) design stratified by diagnosis and sex. Physical function, body composition, quality of life, and fatigue are assessed prior to hematopoietic stem cell transplant (prior to initiating preparatory treatment) and 24±5 days post hematopoietic stem cell transplant (Follow-up 1); physical function and quality of life are also assessed 6-months post hematopoietic stem cell transplant (Follow-up 2). The primary outcome is between-group difference in the 6-minute walk test change scores (Follow-up 1-Pre-transplant; final enrolment goal N = 23/group). We hypothesize that 1) neuromuscular electrical stimulation will attenuate hematopoietic stem cell transplant-induced adverse effects on physical function, muscle mass, quality of life, and fatigue compared to sham at Follow-up 1, and 2) Pre-transplant physical function will significantly predict fatigue and quality of life at Follow-up 2. We will also describe feasibility and acceptability of neuromuscular electrical stimulation during hematopoietic stem cell transplant. This proposal will improve rehabilitative patient care and quality of life by determining efficacy and feasibility of a currently underutilized therapeutic strategy aimed at maintaining daily function and reducing the impact of a potent and widely used cancer treatment. This trial is registered with clinicaltrials.gov (NCT04364256).

Risk and predictors of penile cancer in US Veterans with HIV.

OBJECTIVES: People living with HIV (PWH) may have an increased burden of penile cancer. We aimed to evaluate the risk of penile cancer in PWH compared to that of the general population. DESIGN: We conducted a nationwide retrospective matched cohort study of penile cancer incidence among veterans living with HIV (VWH) compared to veterans without HIV. METHODS: We compared penile cancer incidence rates in 44,173 VWH to those of veterans without Human Immunodeficiency virus (HIV) (N = 159,443; 4:1 matched in age. We used Cox regression models to estimate Hazard ratios (HRs) and 95% confidence intervals (CIs) for associations with HIV infection and for penile cancer risk factors. RESULTS: HIV positivity was associated with an increased risk of penile cancer, with adjusted hazard ratios (HR) of 2.63 (95% CI: 1.64-4.23) when adjusting for age, race/ethnicity, baseline BMI, smoking and alcohol use, economic means test, and history of condyloma. The risk increased to HR = 4.25 (95% CI: 2.75-6.57) when adjusting for all factors except history of condyloma. Risk factors for penile cancer in VWH included lower nadir CD4 count, <50% of follow-up time with undetectable HIV viral load, and history of condyloma. CONCLUSIONS: VWH--particularly those with low CD4 counts, detectable HIV viral loads, or history of condyloma--are at increased risk of penile cancer, suggesting the penile cancer prevention activities are needed in this population.

Clinical Relevance of Physical Function Outcomes in Cancer Cachexia.

Managing clinical manifestations of cancer/treatment burden on functional status and quality of life remains paramount across the cancer trajectory, particularly for patients with cachexia who display reduced functional capacity. However, clinically relevant criteria for classifying functional impairment at a single point in time or for classifying meaningful functional changes subsequent to disease and/or treatment progression are lacking. This unmet clinical need remains a major obstacle to the development of therapies for cancer cachexia. This review aims to describe current literature-based evidence for clinically meaningful criteria for (1) functional impairment at a single timepoint between cancer patients with or without cachexia and (2) changes in physical function over time across interventional studies conducted in patients with cancer cachexia. The most common functional assessment in cross-sectional and interventional studies was hand grip strength (HGS). We observed suggestive evidence that an HGS deficit between 3 and 6 kg in cancer cachexia may display clinical relevance. In interventional studies, we observed that long-duration multimodal therapies with a focus on skeletal muscle may benefit HGS in patients with considerable weight loss. Future studies should derive cohort-specific clinically relevant criteria to confirm these observations in addition to other functional outcomes and investigate appropriate patient-reported anchors.

IKKß deletion from CNS macrophages increases neuronal excitability and accelerates the onset of EAE, while from peripheral macrophages reduces disease severity.

BACKGROUND: Multiple sclerosis (MS) is a neuroinflammatory demyelinating disease characterized by motor deficits and cognitive decline. Many immune aspects of the disease are understood through studies in the experimental autoimmune encephalomyelitis (EAE) model, including the contribution of the NF-κB transcription factor to neuroinflammation. However, the cell-specific roles of NF-κB to EAE and its cognitive comorbidities still needs further investigation. We have previously shown that the myeloid cell NF-κB plays a role in the healthy brain by exerting homeostatic regulation of neuronal excitability and synaptic plasticity and here we investigated its role in EAE. METHODS: We used constitutive MφIKKßΚΟ mice, in which depletion of IKKß, the main activating kinase of NF-κB, was global to CNS and peripheral macrophages, and ΜgΙΚΚßKO mice, in which depletion was inducible and specific to CNS macrophages by 28 days after tamoxifen administration. We subjected these mice to MOG35-55 induced EAE and cuprizone-induced demyelination. We measured pathology by immunohistochemistry, investigated molecular mechanisms by RNA sequencing analysis and studied neuronal functions by in vivo electrophysiology in awake animals. RESULTS: Global depletion of IKKß from myeloid cells in MφIKKßΚΟ mice accelerated the onset and significantly supressed chronic EAE. Knocking out IKKß only from CNS resident macrophages accelerated the onset and exacerbated chronic EAE, accompanied by earlier demyelination and immune cell infiltration but had no effect in cuprizone-induced demyelination. Peripheral T cell effector functions were not affected by myeloid cell deletion of IKKß, but CNS resident mechanisms, such as microglial activation and neuronal hyperexcitability were altered from early in EAE. Lastly, depletion of myeloid cell IKKß resulted in enhanced late long-term potentiation in EAE. CONCLUSIONS: IKKß-mediated activation of NF-κΒ in myeloid cells has opposing roles in EAE depending on the cell type and the disease stage. In CNS macrophages it is protective while in peripheral macrophages it is disease-promoting and acts mainly during chronic disease. Although clinically protective, CNS myeloid cell IKKß deletion dysregulates neuronal excitability and synaptic plasticity in EAE. These effects of IKKß on brain cognitive abilities deserve special consideration when therapeutic interventions that inhibit NF-κB are used in MS.

Active natural compounds perturb the melanoma risk-gene network.

Cutaneous melanoma is an aggressive type of skin cancer with a complex genetic landscape caused by the malignant transformation of melanocytes. This study aimed at providing an in silico network model based on the systematic profiling of the melanoma-associated genes considering germline mutations, somatic mutations, and genome-wide association study signals accounting for a total of 232 unique melanoma risk genes. A protein-protein interaction network was constructed using the melanoma risk genes as seeds and evaluated to describe the functional landscape in which the melanoma genes operate within the cellular milieu. Not only were the majority of the melanoma risk genes able to interact with each other at the protein level within the core of the network, but this showed significant enrichment for genes whose expression is altered in human melanoma specimens. Functional annotation showed the melanoma risk network to be significantly associated with processes related to DNA metabolism and telomeres, DNA damage and repair, cellular ageing, and response to radiation. We further explored whether the melanoma risk network could be used as an in silico tool to predict the efficacy of anti-melanoma phytochemicals, that are considered active molecules with potentially less systemic toxicity than classical cytotoxic drugs. A significant portion of the melanoma risk network showed differential expression when SK-MEL-28 human melanoma cells were exposed to the phytochemicals harmine and berberine chloride. This reinforced our hypothesis that the network modeling approach not only provides an alternative way to identify molecular pathways relevant to disease but it may also represent an alternative screening approach to prioritize potentially active compounds.

Phase Ia/b Study of Giredestrant ± Palbociclib and ± Luteinizing Hormone-Releasing Hormone Agonists in Estrogen Receptor-Positive, HER2-Negative, Locally Advanced/Metastatic Breast Cancer.

PURPOSE: Giredestrant is an investigational next-generation, oral, selective estrogen receptor antagonist and degrader for the treatment of estrogen receptor-positive (ER+) breast cancer. We present the primary analysis results of the phase Ia/b GO39932 study (NCT03332797). PATIENTS AND METHODS: Patients with ER+, HER2-negative locally advanced/metastatic breast cancer previously treated with endocrine therapy received single-agent giredestrant (10, 30, 90, or 250 mg), or giredestrant (100 mg) ± palbociclib 125 mg ± luteinizing hormone-releasing hormone (LHRH) agonist. Detailed cardiovascular assessment was conducted with giredestrant 100 mg. Endpoints included safety (primary), pharmacokinetics, pharmacodynamics, and efficacy. RESULTS: As of January 28, 2021, with 175 patients enrolled, no dose-limiting toxicity was observed, and the MTD was not reached. Adverse events (AE) related to giredestrant occurred in 64.9% and 59.4% of patients in the single-agent ± LHRH agonist and giredestrant + palbociclib ± LHRH agonist cohorts, respectively (giredestrant-only-related grade 3/4 AEs were reported in 4.5% of patients across the single-agent cohorts and 3.1% of those with giredestrant + palbociclib). Dose-dependent asymptomatic bradycardia was observed, but no clinically significant changes in cardiac-related outcomes: heart rate, blood pressure, or exercise duration. Clinical benefit was observed in all cohorts (48.6% of patients in the single-agent cohort and 81.3% in the giredestrant + palbociclib ± LHRH agonist cohort), with no clear dose relationship, including in patients with ESR1-mutated tumors. CONCLUSIONS: Giredestrant was well tolerated and clinically active in patients who progressed on prior endocrine therapy. Results warrant further evaluation of giredestrant in randomized trials in early- and late-stage ER+ breast cancer.

In Vitro Cytotoxic Effects of Ferruginol Analogues in Sk-MEL28 Human Melanoma Cells.

Ferruginol is a promising abietane-type antitumor diterpene able to induce apoptosis in SK-Mel-28 human malignant melanoma. We aim to increase this activity by testing the effect of a small library of ferruginol analogues. After a screening of their antiproliferative activity (SRB staining, 48 h) on SK-Mel-28 cells the analogue 18-aminoferruginol (GI50 ≈ 10 µM) was further selected for mechanistic studies including induction of apoptosis (DAPI staining, p < 0.001), changes in cell morphology associated with the treatment (cell shrinkage and membrane blebbing), induction of caspase-3/7 activity (2.5 at 48 h, 6.5 at 72 h; p < 0.0001), changes in the mitochondrial membrane potential (not significant) and in vitro effects on cell migration and cell invasion (Transwell assays, not significant). The results were compared to those of the parent molecule (ferruginol, GI50 ≈ 50 µM, depolarisation of mitochondrial membrane p < 0.01 at 72 h; no caspases 3/7 activation) and paclitaxel (GI50 ≈ 10 nM; caspases 3/7 activation p < 0.0001) as a reference drug. Computational studies of the antiproliferative activity of 18-aminoferruginol show a consistent improvement in the activity over ferruginol across a vast majority of cancer cells in the NCI60 panel. In conclusion, we demonstrate here that the derivatisation of ferruginol into 18-aminoferruginol increases its antiproliferative activity five times in SK-MEL-28 cells and changes the apoptotic mechanism of its parent molecule, ferruginol.

Structural dynamics at the active site of the cancer-associated flavoenzyme NQO1 probed by chemical modification with PMSF.

A large conformational heterogeneity of human NAD(P)H:quinone oxidoreductase 1 (NQO1), a flavoprotein associated with various human diseases, has been observed to occur in the catalytic site of the enzyme. Here, we report the X-ray structure of NQO1 with phenylmethylsulfonyl fluoride (PMSF) at 1.6 Å resolution. Activity assays confirmed that, despite being covalently bound to the Tyr128 residue at the catalytic site, PMSF did not abolish NQO1 activity. This may indicate that the PMSF molecule does not reduce the high flexibility of Tyr128, thus allowing NADH and DCPIP substrates to bind to the enzyme. Our results show that targeting Tyr128, a key residue in NQO1 function, with small covalently bound molecules could possibly not be a good drug discovery strategy to inhibit this enzyme.

A Review of Nutraceuticals in Cancer Cachexia.

Cancer cachexia is largely characterized by muscle wasting and inflammation, leading to weight loss, functional impairment, poor quality of life (QOL), and reduced survival. The main barrier to therapeutic development is a lack of efficacy for improving clinically relevant outcomes, such as physical function or QOL, yet most nutraceutical studies focus on body weight. This review describes clinical and pre-clinical nutraceutical studies outside the context of complex nutritional and/or multimodal interventions, in the setting of cancer cachexia, in view of considerations for future clinical trial design. Clinical studies mostly utilized polyunsaturated fatty acids or amino acids/derivatives, and they primarily focused on body weight and, secondarily, on muscle mass and/or QOL. The few studies that measured physical function almost exclusively utilized handgrip strength with, predominantly, no time and/or group effect. Preclinical studies focused mainly on amino acids/derivatives and polyphenols, assessing body weight, muscle mass, and occasionally physical function. While this review does not provide sufficient evidence of the efficacy of nutraceuticals for cancer cachexia, more preclinical and adequately powered clinical studies are needed, and they should focus on clinically meaningful outcomes, including physical function and QOL.

Imaging Techniques to Determine Degree of Sarcopenia and Systemic Inflammation in Advanced Renal Cell Carcinoma.

PURPOSE OF REVIEW: The purpose of this review is to provide an up-to-date understanding regarding the literature on sarcopenia and inflammation as prognostic factors in the context of renal cell carcinoma (RCC). RECENT FINDINGS: Sarcopenia is increasingly recognized as a prognostic factor in RCC. Emerging literature suggests monitoring quantity of muscle on successive imaging and examining muscle density may be additionally informative. Inflammation has prognostic ability in RCC and is also considered a key contributor to development and progression of both RCC and sarcopenia. Recent studies suggest these two prognostic factors together may provide additional prognostic ability when used in combination. Ongoing developments include quality control regarding sarcopenia research and imaging, improving understanding of muscle loss mechanisms, and enhancing clinical incorporation of sarcopenia via improving imaging analysis practicality (i.e., artificial intelligence) and feasible biomarkers. Sarcopenia and systemic inflammation are complementary prognostic factors for adverse outcomes in patients with RCC. Further study on high-quality sarcopenia assessment standardization and expedited sarcopenia assessment is desired for eventual routine clinical incorporation of these prognostic factors.

Pilot clinical trial of macimorelin to assess safety and efficacy in patients with cancer cachexia.

BACKGROUND: Cancer cachexia is associated with reduced body weight, appetite and quality of life (QOL) with no approved treatments. Growth hormone secretagogues like macimorelin have potential to mitigate these effects. METHODS: This pilot study assessed the safety and efficacy of macimorelin for 1 week. Efficacy was defined a priori as 1-week change in body weight (≥0.8 kg), plasma insulin-like growth factor (IGF)-1 (≥50 ng/mL) or QOL (≥15%). Secondary outcomes included food intake, appetite, functional performance, energy expenditure and safety laboratory parameters. Patients with cancer cachexia were randomized to 0.5 or 1.0 mg/kg macimorelin or placebo; outcomes were assessed non-parametrically. RESULTS: Participants receiving at least one of either macimorelin dose were combined (N = 10; 100% male; median age = 65.50 ± 2.12) and compared with placebo (N = 5; 80% male; median age = 68.00 ± 6.19). Efficacy criteria achieved: body weight (macimorelin N = 2; placebo N = 0; P = 0.92); IGF-1 (macimorelin N = 0; placebo N = 0); QOL by Anderson Symptom Assessment Scale (macimorelin N = 4; placebo N = 1; P = 1.00) or Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F; macimorelin N = 3; placebo N = 0; P = 0.50). No related serious or non-serious adverse events were reported. In macimorelin recipients, change in FACIT-F was directly associated with change in body weight (r = 0.92, P = 0.001), IGF-1 (r = 0.80, P = 0.01), and caloric intake (r = 0.83, P = 0.005), and inversely associated with change in energy expenditure (r = -0.67, P = 0.05). CONCLUSIONS: Daily oral macimorelin for 1 week was safe and numerically improved body weight and QOL in patients with cancer cachexia compared with placebo. Longer term administration should be evaluated for mitigation of cancer-induced reductions in body weight, appetite and QOL in larger studies.

EXT418, a novel long-acting ghrelin, mitigates Lewis lung carcinoma induced cachexia in mice.

BACKGROUND: Ghrelin is a potential therapy for cachexia due to its orexigenic properties and anabolic effects on muscle and fat. However, its clinical use is limited by the short half-life of active (acylated) ghrelin (~11 min in humans). EXT418 is a novel long-acting, constitutively active ghrelin analog created by covalently linking it to a vitamin D derivative. Here, we evaluated the effects and mechanisms of action of EXT418 on Lewis lung carcinoma (LLC)-induced cachexia in mice. METHODS: Male C57BL/6J mice (5- to 7-month-old) were implanted with 1 × 106 heat-killed (HK) or live LLC cells. When the tumour was palpable, mice were injected with vehicle (T + V) or EXT418 daily (T + 418 Daily, 0.25 mg/kg/day) or every other day (T + 418 EOD, 0.5 mg/kg/EOD) for up to 14 days, whereas HK-treated mice were given vehicle (HK + V). Subsets of T + 418 Daily or EOD-treated mice were pair-fed to the T + V group. Body composition and grip strength were evaluated before tumour implantation and at the end of the experiment. Molecular markers were probed in muscles upon termination. RESULTS: In tumour-bearing mice, administration of EXT418 daily or EOD partially prevented weight loss (T + V vs. T + 418 Daily, P = 0.030; and vs. T + 418 EOD, P = 0.020). Similar effects were observed in whole body fat and lean body mass. Grip strength in tumour-bearing mice was improved by EXT418 daily (P = 0.010) or EOD (P = 0.008) administration compared with vehicle-treated mice. These effects of EXT418 on weight and grip strength were partially independent of food intake. EXT418 daily administration also improved type IIA (P = 0.015), IIB (P = 0.037) and IIX (P = 0.050) fibre cross-sectional area (CSA) in tibialis anterior (TA) and EXT418 EOD improved CSA of IIB fibres in red gastrocnemius (GAS; P = 0.005). In skeletal muscles, tumour-induced increases in atrogenes Fbxo32 and Trim63 were ameliorated by EXT418 treatments (TA and GAS/plantaris, PL), which were independent of food intake. EXT418 administration decreased expression of the mitophagy marker Bnip3 (GAS/PL; P ≤ 0.010). Similar effects of EXT418 EOD were observed in p62 (GAS/PL; P = 0.039). In addition, EXT418 treatments ameliorated the tumour-induced elevation in muscle Il6 transcript levels (TA and GAS/PL), independently of food intake. Il-6 transcript levels in adipose tissue and circulating IL-10 were elevated in response to the tumour but these increases were not significant with EXT418 administration. Tumour mass was not altered by EXT418. CONCLUSIONS: EXT418 mitigates LLC-induced cachexia by attenuating skeletal muscle inflammation, proteolysis, and mitophagy, without affecting tumour mass and partially independent of food intake.

Area deprivation index and segregation on the risk of HIV: a U.S. Veteran case-control study.

Background: Preventing HIV infection remains a critically important tool in the continuing fight against HIV/AIDS. The primary aim is to evaluate the effect and interactions between a composite area-level social determinants of health measure and an area-level measure of residential segregation on the risk of HIV/AIDS in U.S. Veterans. Methods: Using the individual-level patient data from the U.S. Department of Veterans Affairs, we constructed a case-control study of veterans living with HIV/AIDS (VLWH) and age-, sex assigned at birth- and index date-matched controls. We geocoded patient's residential address to ascertain their neighborhood and linked their information to two measures of neighborhood-level disadvantage: area deprivation index (ADI) and isolation index (ISOL). We used logistic regression to estimate the odds ratio (OR) and 95% confidence interval (CI) for comparing VLWH with matched controls. We performed analyses for the entire U.S. and separately for each U.S. Census division. Findings: Overall, living in minority-segregated neighborhoods was associated with a higher risk of HIV (OR: 1.88 (95% CI: 1.79-1.97) while living in higher ADI neighborhoods was associated with a lower risk of HIV (OR: 0.88; 95% CI: 0.84-0.92). The association between living in a higher ADI neighborhood and HIV was inconsistent across divisions, while living in minority-segregated neighborhoods was consistently associated with increased risk across all divisions. In the interaction model, individuals from low ADI and high ISOL neighborhoods had a higher risk of HIV in three divisions: East South Central; West South Central, and Pacific. Interpretation: Our results suggest that residential segregation may prevent people in disadvantaged neighborhoods from protecting themselves from HIV independent from access to health care. There is the need to advance knowledge about the neighborhood-level social-structural factors that influence HIV vulnerability toward developing interventions needed to achieve the goal of ending the HIV epidemic. Funding: US National Cancer Institute.

Survival Analysis in Patients with Laryngeal Cancer: A Retrospective Cohort Study.

INTRODUCTION: The worldwide incidence rate of laryngeal cancer is declining. However, the 5-year survival for these patients has decreased in recent years from 66% to 63%. This may be due to changes in the treatment of the disease. The present study aimed to evaluate the survival rate of patients with LC according to the stage of the disease and the treatment applied. For this purpose, surgical versus organ preservation protocols (OPP) based on chemoradiotherapy were evaluated. METHODS: A retrospective cohort study was conducted in a tertiary hospital. The study included adult patients with a clinical diagnosis of primary LC. Patients with LC and systemic metastases and those with synchronous tumors at diagnosis were excluded. Univariate and multivariate analyses were performed to determine the association between exposure to LC treatment and the time to event (death). Overall survival (OS), cause-specific survival (CSS), and disease-free survival (DFS) were calculated. RESULTS: Patients with advanced tumors (stages III and IV) had almost three times the risk of LC death than those in the initial tumor stages (I and II) [HR CCS = 2.89 (95%CI 1.30-6.39)]; [HR OS = 2.01 (95%CI 1.35-2.98)]. Patients who underwent surgical treatment had a higher chance of survival than those who were treated according to OPP [HR = 0.62; 95%CI (0.38-1.02)] in CSS, 0.74 [95%CI (0.50-1.90)] in OS, and 0.61 [95%CI (0.40-0.91)] in DFS. DISCUSSION: OPP changed the management of patients with advanced stages of LC, establishing CRT as an alternative to surgery. Our data did not reveal clinically relevant differences in OS between patients treated with OPP and those who underwent surgery; however, we reported differences in the DFS rate after five years of follow-up in favor of the surgery-treated group of patients. CONCLUSION: Surgical treatment improves CSS and DFS at five years in patients with initial LC with respect to radiation therapy alone. Furthermore, surgical treatment associated with complementary radiation therapy offers better CSS and DFS in patients with advanced LC.

Progesterone receptor ligands for the treatment of endometriosis.

Estrogen dependence and progesterone resistance play a crucial role in the origin and development of endometriosis. Therefore, hormonal therapies are currently the most effective treatment. Progestins are considered the first-line approach, especially for a long-term management. Progestins are synthetic compounds that mimic the effects of progesterone by binding progesterone receptors. Continuous use of progestins leads to the suppression of ovarian steroidogenesis with anovulation and low serum levels of ovarian steroids, causing endometrial pseudodecidualization. Moreover, they act by interfering on several endometriosis pathogenetic pathways, decreasing inflammation, provoking apoptosis in endometriotic cells, stimulating atrophy or regression of endometrial lesions, inhibiting angiogenesis, and decreasing expression of metalloproteinases, thus diminishing the invasiveness of endometriotic implants. Progestins are effective for pain relief and improvement of the quality of life (QoL). The side effects are limited, and the compounds are available in different formulations and routes of administration and represent, in most cases, an inexpensive treatment option. Dienogest, Medroxyprogesterone acetate and Norethisterone acetate are the labeled progestins for endometriosis, but other progestins, such as Dyhidrogesterone, Levonorgestrel and Desogestrel, have been shown to be effective in the treatment of endometriosis-associated pain. The present review aims to describe the available and emerging evidences on progestins used for the treatment of endometriosis.

The influence of massive jejunectomy on endocrine pancreas of diabetic Goto-Kakizaki.

OBJECTIVE: Several bariatric surgeries have been related to the T2DM improvement in obese patients. Despite the different mechanism invoked for this improvement, many evidences showed that the pancreas cellularity is conditioned for the homeostatic physiological changes after these surgeries. Many authors reported the changes in beta-cell mass after some surgeries in healthy rats. We purpose to analyze the changes in ß-cell cellularity and ß-cell-mass after a severe malabsorptive surgical method. Thus, we studied several parameters of the islet morphometric composition after a massive jejunal resection. MATERIALS AND METHODS: We employed Goto-Kakizaki diabetic non-obese rats, which underwent the 50% resection of middle portion of the jejunum versus a control group. After 3 months, rats were sacrificed and pancreas was immunohistochemicaly studied. RESULTS: The ß-cell mass was analyzed and several parameters about the endocrine islet size distribution were studied. We report an increase of ß-cell mass in massive resection surgical group versus controls. The islet distribution was significant different between both groups. Endocrine islets of surgical group were bigger with a different cellular distribution. CONCLUSION: According to the enteroendocrine changes related to surgeries in jejunum, as in other gastrointestinal portions, the cellularity of islets changes as an adaptive process to glycemic demands.

OBJETIVO: Varias técnicas quirúrgicas bariátricas han sido relacionadas con el mejoramiento de la T2DM en pacientes obesos. Se han invocado distintos mecanismos de porqué se da este mejoramiento y muchas evidencias apuntan a que la celularidad del páncreas cambia por las condiciones fisiológicas tras estas cirugías. Se han publicado cambios en la celularidad beta en ratas sanas sometidas a estos procesos. Y nos proponemos observar dichos cambios en ratas diabéticas tras una resección jejunal masiva. Estudiamos varios parámetros sobre la masa beta y la morfometría de los islotes, que indiquen los procesos celulares que han tenido lugar. MATERIAL Y METODO: Empleamos Goto-Kakizaki, un modelo de rata diabética no obesa, a la que se sometió a una resección del 50%de la poción media del yeyuno. Tras tres meses de supervivencia, las ratas se estudiaron los páncreas mediante inmunocitoquímica. RESULTADOS: Mostramos un incremento de la masa beta en las ratas resecadas frente a los controles. La distribución de islotes fue significativamente distinta entre los grupos, donde los islotes eran mayores en las ratas diabéticas. CONCLUSIÓN: Los cambios glucémicos tras las resecciones masivas yeyunales cambian la celularidad del páncreas como una muestra de la capacidad adaptativa del mismo a las modificaciones.

Maternal rodent exposure to di-(2-ethylhexyl) phthalate decreases muscle mass in the offspring by increasing myostatin.

BACKGROUND: Di-(2-ethylhexyl) phthalate (DEHP) and its metabolites can cross the placenta and may cause birth defects and developmental disorders. However, whether maternal DEHP exposure affects skeletal muscle development in the offspring and the pathways involved are unknown. This study investigated the effects of maternal DEHP exposure and the contribution of myostatin (MSTN) to skeletal muscle development in the offspring. METHODS: Pregnant wild-type and muscle-specific myostatin knockout (MSTN KO) C57BL/6 mice were randomized to receive vehicle (corn oil) or 250 mg/kg DEHP by gavage every other day until their pups were weaned (postnatal day 21 [PND21]). Body weights of the offspring mice were measured longitudinally, and their hindleg muscles were harvested at PD21. Also, C2C12 cells were treated with mono-2-ethylhexyl phthalate (MEHP), the primary metabolite of DEHP, and proteolysis, protein synthesis, and myogenesis markers were measured. The contribution of myostatin to maternal DEHP exposure-induced muscle wasting in the offspring was determined. RESULTS: Maternal DEHP exposure reduced body weight growth, myofibre size, and muscle mass in the offspring compared to controls (Quad: 2.70 ± 0.1 vs. 3.38 ± 0.23, Gastroc: 2.29 ± 0.09 vs. 2.81 ± 0.14, Tibialis: 1.01 ± 0.07 vs. 1.25 ± 0.11, mg/tibial length in mm, all P < 0.01, n = 35). Maternal DEHP exposure significantly increased Myostatin expression (2.45 ± 0.41 vs. 0.03 ± 0.00 DEHP vs. controls, P < 0.01, n = 5), Atrogin-1(2.68 ± 0.65 vs. 0.63 ± 0.01, P < 0.05, n = 5), MuRF1 (1.56 ± 0.51 vs. 0.31 ± 0.01, P < 0.05, n = 5), and Smad2/3 phosphorylation (4.12 ± 0.35 vs. 0.49 ± 0.18, P < 0.05), and decreased MyoD (0.27 ± 0.01 vs. 1.52 ± 0.01, P < 0.05, n = 5), Myogenin (0.25 ± 0.03 vs. 1.95 ± 0.56, P < 0.05, n = 5), and AKT phosphorylation (4.12 ± 0.35 vs. 1.00 ± 0.06, P < 0.05, n = 5), in skeletal muscle of the offspring in MSTNflox/flox , but not in MSTN KO mice. Maternal DEHP exposure resulted in up-regulation of CCAAT/enhancer-binding protein δ (C/EBPδ, 4.12 ± 0.35 vs. 1.00 ± 0.19, P < 0.05, n = 5) in skeletal muscle of the offspring in MSTNflox/flox and MSTN KO mice (4.12 ± 0.35 vs. 4.35 ± 0.28, P > 0.05, n = 5). In vitro, C/EBPδ silencing abrogated the MEHP-induced increases in Myostatin, MuRF-1, and Atrogin-1 and decreases in MyoD and Myogenin expression. CONCLUSIONS: Maternal DEHP exposure impairs skeletal muscle development in the offspring by enhancing the C/EBPδ-myostatin pathway in mice.

UBR2 targets myosin heavy chain IIb and IIx for degradation: Molecular mechanism essential for cancer-induced muscle wasting.

Cancer cachexia is a lethal metabolic syndrome featuring muscle wasting with preferential loss of fast-twitching muscle mass through an undefined mechanism. Here, we show that cancer induces muscle wasting by selectively degrading myosin heavy chain (MHC) subtypes IIb and IIx through E3 ligase UBR2-mediated ubiquitylation. Induction of MHC loss and atrophy in C2C12 myotubes and mouse tibialis anterior (TA) by murine cancer cells required UBR2 up-regulation by cancer. Genetic gain or loss of UBR2 function inversely altered MHC level and muscle mass in TA of tumor-free mice. UBR2 selectively interacted with and ubiquitylated MHC-IIb and MHC-IIx through its substrate recognition and catalytic domain, respectively, in C2C12 myotubes. Elevation of UBR2 in muscle of tumor-bearing or free mice caused loss of MHC-IIb and MHC-IIx but not MHC-I and MHC-IIa or other myofibrillar proteins, including α-actin, troponin, tropomyosin, and tropomodulin. Muscle-specific knockout of UBR2 spared KPC tumor-bearing mice from losing MHC-IIb and MHC-IIx, fast-twitching muscle mass, cross-sectional area, and contractile force. The rectus abdominis (RA) muscle of patients with cachexia-prone cancers displayed a selective reduction of MHC-IIx in correlation with higher UBR2 levels. These data suggest that UBR2 is a regulator of MHC-IIb/IIx essential for cancer-induced muscle wasting, and that therapeutic interventions can be designed by blocking UBR2 up-regulation by cancer.

Staphylococcus epidermidis RP62A's Metabolic Network: Validation and Intervention Strategies.

Increasingly, systems biology is gaining relevance in basic and applied research. The combination of computational biology with wet laboratory methods produces synergy that results in an exponential increase in knowledge of biological systems. The study of microorganisms such as Staphylococcus epidermidis RP62A enables the researcher to understand better their metabolic networks, which allows the design of effective strategies to treat infections caused by this species or others. S. epidermidis is the second most commoncause of infection in patients with joint implants, so treating its proliferation seems vital for public health. There are different approaches to the analysis of metabolic networks. Flux balance analysis (FBA) is one of the most widespread streams of research. It allows the study of large metabolic networks, the study their structural properties, the optimization of metabolic flux, and the search for intervention strategies to modify the state of the metabolic network. This work presents the validation of the Staphylococcus epidermidis RP62A metabolic network model elaborated by Díaz Calvo et al. Then, we elaborate further on the network analysis's essential reactions. The full set of essential reactions (including a previously unobserved one) was computed, and we classified them into equivalence classes. Some proposals to intervene in the network and design knock-outs by studying minimal cut sets of small length are also introduced. In particular, minimal cut sets related to the medium (including exchange reactions associated with medium metabolites) have been computed. In this sense, the unique external MCS (composed of cysteine and sulfate ion) has been found, and all hybrid MCS (based on knocking out both internal and exchange reactions) of length two have also been computed. The paper also points out the possible importance of these new intervention strategies.

Purification, characterization, and preliminary serial crystallography diffraction advances structure determination of full-length human particulate guanylyl cyclase A receptor.

Particulate Guanylyl Cyclase Receptor A (pGC-A) is a natriuretic peptide membrane receptor, playing a vital role in controlling cardiovascular, renal, and endocrine functions. The extracellular domain interacts with natriuretic peptides and triggers the intracellular guanylyl cyclase domain to convert GTP to cGMP. To effectively develop methods to regulate pGC-A, structural information on the full-length form is needed. However, structural data on the transmembrane and intracellular domains are lacking. This work presents expression and optimization using baculovirus, along with the first purification of functional full-length human pGC-A. In vitro assays revealed the pGC-A tetramer was functional in detergent micelle solution. Based on our purification results and previous findings that dimer formation is required for functionality, we propose a tetramer complex model with two functional subunits. Previous research suggested pGC-A signal transduction is an ATP-dependent, two-step mechanism. Our results show the binding ligand also moderately activates pGC-A, and ATP is not crucial for activation of guanylyl cyclase. Furthermore, crystallization of full-length pGC-A was achieved, toward determination of its structure. Needle-shaped crystals with 3 Å diffraction were observed by serial crystallography. This work paves the road for determination of the full-length pGC-A structure and provides new information on the signal transduction mechanism.