Effect of malnutrition and short-term refeeding on peripheral blood mononuclear cell mitochondrial complex I activity in humans

Role of Mitochondria in Inflammatory Bowel Diseases: A Systematic Review

Mitochondria are key cellular organelles whose main function is maintaining cell bioenergetics by producing ATP through oxidative phosphorylation. However, mitochondria are involved in a much higher number of cellular processes. Mitochondria are the home of key metabolic pathways like the tricarboxylic acid cycle and β-oxidation of fatty acids, as well as biosynthetic pathways of key products like nucleotides and amino acids, the control of the redox balance of the cell and detoxifying the cell from H2S and NH3. This plethora of critical functions within the cell is the reason mitochondrial function is involved in several complex disorders (apart from pure mitochondrial disorders), among them inflammatory bowel diseases (IBD). IBD are a group of chronic, inflammatory disorders of the gut, mainly composed of ulcerative colitis and Crohn's disease. In this review, we present the current knowledge regarding the impact of mitochondrial dysfunction in the context of IBD. The role of mitochondria in both intestinal mucosa and immune cell populations are discussed, as well as the role of mitochondrial function in mechanisms like mucosal repair, the microbiota- and brain-gut axes and the development of colitis-associated colorectal cancer.

The Effects of Critical Care Nutrition on Weight Gain in African Penguin (Spheniscus demersus) Chicks

Nutritional support in malnourished animals is an essential aspect of wildlife rehabilitation; this support is especially relevant when providing lifesaving nutrition to endangered species such as the African penguin (Spheniscus demersus). This study investigated the short-term effects of a commercially available, semi-elemental, critical care diet compared with a hand-made fish formula. Twenty-one African penguin chicks were selected on admission to the Southern African Foundation for the Conservation of Costal Birds in Cape Town, South Africa, in November 2015. Initial assessment included body weight, a full clinical exam, white blood cell count, packed cell volume, and total plasma protein. Ten animals received the commercial critical care diet, whereas a control group of 11 animals were fed hand-made formula for the 2-week study period. All animals were weighed daily and blood sampling was repeated after 14 days. The median weight of both groups increased significantly over 14 days (critical care diet χ2 = 10.1, P = 0.002; control χ2 = 7.4, P = 0.006). The difference was not significant between the groups for start weight (χ2 = 0.1, P = 0.725) or end weight (χ2 = 0, P = 1.000) and was not significantly different in the change over time for either absolute numbers (χ2 = 1.7, P = 0.193) or percent gain (χ2 = 0.8, P = 0.36). The values for packed cell volume, total plasma protein, and white blood cell count increased in all animals after the 14-day study period was complete. On the basis of the results of this study, it was determined that the differing diets led to similar weight gain.

Potential mechanisms of multimodal prehabilitation effects on surgical complications: a narrative review

Continuous advances in prehabilitation research over the past several decades have clarified its role in improving preoperative risk factors, yet the evidence demonstrating reduced surgical complications remains uncertain. Describing the potential mechanisms underlying prehabilitation and surgical complications represents an important opportunity to establish biological plausibility, develop targeted therapies, generate hypotheses for future research, and contribute to the rationale for implementation into the standard of care. In this narrative review, we discuss and synthesize the current evidence base for the biological plausibility of multimodal prehabilitation to reduce surgical complications. The goal of this review is to improve prehabilitation interventions and measurement by outlining biologically plausible mechanisms of benefit and generating hypotheses for future research. This is accomplished by synthesizing the available evidence for the mechanistic benefit of exercise, nutrition, and psychological interventions for reducing the incidence and severity of surgical complications reported by the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP). This review was conducted and reported in accordance with a quality assessment scale for narrative reviews. Findings indicate that prehabilitation has biological plausibility to reduce all complications outlined by NSQIP. Mechanisms for prehabilitation to reduce surgical complications include anti-inflammation, enhanced innate immunity, and attenuation of sympathovagal imbalance. Mechanisms vary depending on the intervention protocol and baseline characteristics of the sample. This review highlights the need for more research in this space while proposing potential mechanisms to be included in future investigations.

Tailoring prehabilitation to address the multifactorial nature of functional capacity for surgery

Mounting evidence suggests that recovery begins before the surgical incision. The pre-surgery phase of recovery - the preparation for optimal surgical recovery - can be reinforced with prehabilitation. Prehabilitation is the approach of enhancing the functional capacity of the individual to enable them to withstand a stressful event. With this narrative review, we apply the Wilson & Cleary conceptual model of patient outcomes to specify the complex and integrative relationship of health factors that limit functional capacity before surgery. To have the greatest impact on patient outcomes, prehabilitation programs require individualized and coordinated care from medical, nutritional, psychosocial, and exercise services. This article is protected by copyright. All rights reserved.

Prehabilitation, enhanced recovery after surgery, or both? A narrative review

This narrative review presents a biological rationale and evidence to describe how the preoperative condition of the patient contributes to postoperative morbidity. Any preoperative condition that prevents a patient from tolerating the physiological stress of surgery (e.g. poor cardiopulmonary reserve, sarcopaenia), impairs the stress response (e.g. malnutrition, frailty), and/or augments the catabolic response to stress (e.g. insulin resistance) is a risk factor for poor surgical outcomes. Prehabilitation interventions that include exercise, nutrition, and psychosocial components can be applied before surgery to strengthen physiological reserve and enhance functional capacity, which, in turn, supports recovery through attaining surgical resilience. Prehabilitation complements Enhanced Recovery After Surgery (ERAS) care to achieve optimal patient outcomes because recovery is not a passive process and it begins preoperatively.

Perinatally acquired HIV infection is associated with abnormal blood mitochondrial function during childhood/adolescence

OBJECTIVE

We assessed differences in mitochondrial function between youth living with perinatal HIV (YPHIV) and youth perinatally HIV-exposed but uninfected (YPHEU).

DESIGN

Cross-sectional analysis.

METHODS

We measured lactate and pyruvate values, as well as mitochondrial Complex I and Complex IV activity in peripheral blood mononuclear cells. Logistic or linear regression models were fit, as appropriate, to assess the association between PHIV status and each mitochondrial parameter, adjusted for confounders. We introduced interaction terms to assess effect modification of PHIV status on the relationship between anthropometric factors and each mitochondrial parameter. Among YPHIV, similar regression models were fit to assess the relationship between HIV-associated factors and each mitochondrial outcome.

RESULTS

A total of 243 YPHIV and 118 YPHEU were compared. On average, YPHIV had higher lactate/pyruvate ratio (β: 7.511, 95% confidence interval [95% CI]: 0.402, 14.620) and Complex IV activity (β: 0.037, 95% CI: 0.002, 0.072) compared to YPHEU, adjusted for confounders. Among YPHIV, body mass index Z score (BMIZ) and Complex I activity were inversely associated, whereas, among YPHEU, there was a positive association (β for interaction: -0.048, P = 0.003). Among YPHIV, current (β: -0.789, 95% CI: -1.174, -0.404) and nadir CD4+% (β: -0.605, 95% CI: -1.086, -0.125) were inversely associated with lactate/pyruvate ratio; higher current (4.491, 95% CI: 0.754, 8.229) and peak (7.978, 95% CI: 1.499, 14.457) HIV RNA levels were positively associated with lactate/pyruvate ratio in adjusted models.

CONCLUSIONS

Mitochondrial function and substrate utilization appear perturbed in YPHIV compared to YPHEU. Increasing immunosuppression and viremia are associated with mitochondrial dysfunction among YPHIV.

Metabolic and Immunological Effects of Intermittent Fasting on a Ketogenic Diet Containing Medium-Chain Triglycerides in Healthy Dogs

In several species, intermittent fasting (IF) has been shown to have beneficial effects, including delayed aging, increased lifespan, increased insulin sensitivity, reduced ischemic tissue damage, delayed onset of neurodegenerative disease and improved neuronal repair following injury. However, the metabolic and immunological effects of IF have not been well-established in dogs. The aim of this study was to examine the effects of a 48 h IF regimen using a low fat and a high fat diet in healthy dogs by quantifying the metabolic, hormonal, and immunological changes. We hypothesized that IF dogs would have higher blood ketone and ghrelin concentrations, lower blood leptin, insulin and glucose concentrations, and signs of immunosuppression compared to dogs eating daily. Ten healthy adult dogs were randomized into three group and underwent three feeding regimes in a 3 × 3 Latin square design: twice a day feeding on a low fat (23% energy from fat; LF) diet, 48 h fasting on a low fat diet, and 48 h fasting on a high fat enriched with medium-chain triglycerides (68% energy from fat; HF) diet. Body weight, food intake, activity, blood glucose, β-hydroxybutyrate, leptin, ghrelin, and insulin were measured. Lymphocyte proliferation and neutrophil/macrophage phagocytosis and respiratory burst were measured as markers of immune function. Nuclear magnetic resonance spectroscopy was used to relatively quantify plasma metabolites. When the dogs were IF on a HF diet, they had the highest concentration of blood ketones (mean 0.061 mmol/L, SD 0.024), whereas they had the lowest concentration (mean 0.018 mmol/L, SD 0.004) when fed daily. Blood glucose and insulin concentrations were lower in IF dogs on a HF diet compared to daily feeding or IF on a LF diet. There was an increase in plasma β-hydroxybutyrate concentrations, and a reduction in glucose and insulin concentrations when dogs were IF on a HF diet. There was only a decline in the immune parameters studied when the dogs were IF on a LF diet, which was not seen when on the HF diet. The results of this study indicate the potential of IF to be further investigated as a potential beneficial feeding regime for dogs.

Nutrition Screening vs Nutrition Assessment: What's the Difference?

Screening and assessment imply different processes, with the former indicating risk factors for a deprived nutrition condition and the latter providing the nutrition diagnosis. Both should be routinely performed at hospital admission according to recommended guidelines; however, this is not the reality worldwide, and undernutrition remains highly prevalent in the hospital setting. Therefore, the objective of the current review is to delve into the principles leading to nutrition status deficiencies and how they should be addressed by screening and assessment. A critical appraisal for the reasons associated with the misunderstanding between screening and assessing is proposed without further discussing the many available screening tools while approaching some of the assessment instruments.

Selenium and zinc protect brain mitochondrial antioxidants and electron transport chain enzymes following postnatal protein malnutrition

AIMS

Selenium (Se) and zinc (Zn) are trace elements required for optimal brain functions. Thus, the role of Se and Zn against protein malnutrition induced oxidative stress on mitochondrial antioxidants and electron transport chain (ETC) enzymes from rats' brain were investigated.

MAIN METHODS

Normal protein (NP) and low protein (LP) rats were fed with diets containing 16% and 5% casein respectively for a period of 10weeks. Then the rats were supplemented with Se and Zn at a concentration of 0.15mgL(-1) and 227mgL(-1) in drinking water for 3weeks after which the rats were sacrificed.

KEY FINDINGS

The results obtained from the study showed significant (p<0.05) increase in lipid peroxidation (LPO), ROS production, oxidized glutathione (GSSG) levels and mitochondrial swelling and significant (p<0.05) reductions in catalase (CAT) and Mn-superoxide dismutase (Mn-SOD) activities, glutathione (GSH) levels, GSH/GSSG ratio and MTT reduction as a result of LP ingestion. The activities of mitochondrial ETC enzymes were also significantly inhibited in both the cortex and cerebellum of LP-fed rats. Supplementation with either Se or Zn restored the alterations in all the parameters.

SIGNIFICANCE

The study showed that Se and Zn might be beneficial in protecting mitochondrial antioxidants and ETC enzymes against protein malnutrition induced oxidative stress.

Anthropometrics Identify Wasting in Patients Undergoing Surgery for Encapsulating Peritoneal Sclerosis

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INTRODUCTION

Encapsulating peritoneal sclerosis (EPS) is a serious complication of peritoneal dialysis in which gastrointestinal (GI) symptoms reduce appetite and dietary intake. Adequate nutrition is important, especially if surgery is required. Although the incidence of EPS is low, the present report is able to detail preoperative nutrition status and treatment in a large cohort of patients from a national EPS referral center. ♦

METHODS

Of 51 patients admitted to this EPS specialist center hospital for their first peritonectomy in the study period, 50 had a preoperative dietetic assessment, and 49 underwent upper-arm anthropometry. ♦

RESULTS

Mean body mass index (BMI) was 20.6 kg/m(2). Mean weight loss was 14% of body weight in the preceding 6 months, with 35 of 50 patients losing more than 10%. On anthropometry, 25 of 49 patients were below the 5th percentile for mid-arm circumference (MAC), 17 of 49 were below for triceps skinfold thickness (TSF), and 21 of 49 were below for mid-arm muscle circumference (MAMC). Mean handgrip strength (HGS) was 60% of normal, with 43 of 49 patients being below 85% of normal. Appetite was poor in 21 of 50 patients, and 37 of 50 had upper and 40 of 50 had lower GI symptoms. By subjective global assessment, 27 of 51 patients were graded as severely malnourished, and 5 of 51, as well-nourished. Mean serum albumin was 28 g/L and did not correlate with BMI, MAC, TSF, MAMC, or HGS. In most patients, C-reactive protein was elevated (mean: 111 mg/L). Preoperative parenteral nutrition was given to 46 of 51 patients for a mean of 21 days. ♦

DISCUSSION

Our findings demonstrate the poor nutrition status of patients admitted for EPS surgical intervention. Anthropometrics reveal depleted fat and lean body mass in EPS patients, which might be a result of anorexia and inflammation, and the reason that albumin was not an accurate marker of nutrition. Poor nutrition status is likely to negatively affect outcome in this patient group. ♦

CONCLUSIONS

Early recognition of GI symptoms may herald a diagnosis of EPS. Optimization of preoperative nutrition status with intensive nutrition support is needed.

Effect of nutritional support on mitochondrial complex I activity in malnourished patients with anorexia nervosa

Previous studies have shown a reduction in lymphocyte mitochondrial complex I activity (CIA) in malnourished patients, which is restored after refeeding. Our aim was to evaluate the usefulness of CIA as an indicator of nutritional status in anorexia nervosa patients. Twelve malnourished anorexia nervosa females (mean age, 24.5 years) were admitted to the Eating Disorders Unit. Basal and weekly anthropometrics, bioelectric impedance (BIA), body composition, and CIA were performed until discharge. Patients were matched to 25 healthy females and refeeding was adjusted according to the Unit’s protocol. Statistics were used as appropriated and significance was reached at p < 0.05. Patients showed a significant reduction in body mass index, fat mass and fat free mass (FFM), triceps skinfold, and waist circumference on admission as compared with the control group. Parameters improved during hospitalization, but they failed to reach normal values at discharge. Compared with controls, CIA was significantly lower in patients on admission (2.16 vs. 5.68 nmol·min−1·mg protein−1). Refeeding and weight gain did not restore CIA. A positive association (r2= 0.69) was found between FFM and CIA in patients at discharge. Malnourished females with anorexia nervosa have lower CIA than controls that is not recovered after refeeding. This could be because of a low FFM exacerbated by physical inactivity while in hospital.

Effects of phytate on thyroid gland of rats intoxicated with cadmium

Cadmium (Cd) is one of the most dangerous occupational and environmental toxins. The objective of the present study is to examine the potential prophylactic effects of phytic acid (PA) on thyroid hormones of male rats intoxicated with Cd. The male albino rats were divided into five groups: group I (control) was fed with the basal diet, group II was intoxicated with Cd in drinking water, groups III, IV, and V were intoxicated with Cd in drinking water and fed with the diet containing 3.5, 7, and 10 g of PA/kg, respectively. The results indicated that the serum calcium, iron (Fe), and total Fe binding capacity levels and serum T3 and T4 in Cd-treated rats of group II were decreased when compared with the control group, while PA-administered groups with Cd showed a significant improvement when compared with the Cd-treated rats only. Serum thyroid stimulating hormone (TSH) level was significantly increased in Cd-treated rats compared with the control group, while the addition of PA in diet decreased the high levels of TSH. These results indicated a prophylactic effect of PA against Cd-induced toxicity in rats.

Serum Phosphate Predicts Early Mortality among Underweight Adults Starting ART in Zambia: A Novel Context for Refeeding Syndrome?

Background. Low body mass index (BMI) at antiretroviral therapy (ART) initiation is associated with early mortality, but the etiology is not well understood. We hypothesized that low pretreatment serum phosphate, a critical cellular metabolism intermediate primarily stored in skeletal muscle, may predict mortality within the first 12 weeks of ART. Methods. We prospectively studied 352 HIV-infected adults initiating ART in Lusaka, Zambia to estimate the odds of death for each 0.1 mmol/L decrease in baseline phosphate after adjusting for established predictors of mortality. Results. The distribution of phosphate values was similar across BMI categories (median value 1.2 mmol/L). Among the 145 participants with BMI <18.5 kg/m², 28 (19%) died within 12 weeks. Lower pretreatment serum phosphate was associated with increased mortality (odds ratio (OR) 1.24 per 0.1 mmol/L decrement, 95% CI: 1.05 to 1.47; P = 0.01) after adjusting for sex, age, and CD4⁺ lymphocyte count. A similar relationship was not observed among participants with BMI ≥18.5 kg/m² (OR 0.96, 95% CI: 0.76 to 1.21; P = 0.74). Conclusions. The association of low pretreatment serum phosphate level and early ART mortality among undernourished individuals may represent a variant of the refeeding syndrome. Further studies of cellular metabolism in this population are needed.

Recurrent pancreatitis in ornithine transcarbamylase deficiency

Ornithine transcarbamylase (OTC) deficiency is a urea cycle defect with varying frequency and severity of episodes of hyperammonemia. We report three patients with OTC deficiency with recurrent pancreatitis. The pathogenesis of acute pancreatitis in this patient population requires further elucidation. Pancreatitis significantly affected dietary/metabolic management and increased frequency of hospitalizations.

Short-term starvation and mitochondrial dysfunction - a possible mechanism leading to postoperative insulin resistance

BACKGROUND

Preoperative starvation results in the development of insulin resistance. Measures to attenuate the development of insulin resistance, such as preoperative carbohydrate loading, lead to clinical benefits. However, the mechanisms that underlie the development of insulin resistance during starvation and its attenuation by preoperative carbohydrate loading remain to be defined. Insulin resistance associated with type 2 diabetes and ageing has been linked to mitochondrial dysfunction. The metabolic consequences of preoperative starvation and carbohydrate loading and mechanisms linking insulin resistance to impaired mitochondrial function are discussed.

METHODS

Searches of the Medline and Science Citation Index databases were performed using various key words in combinations with the Boolean operators AND, OR and NOT. Key journals, nutrition and metabolism textbooks and the reference lists of key articles were also hand searched.

RESULTS

Animal studies have shown that short-term energy deprivation decreases mitochondrial ATP synthesis capacity and complex activity, and increases oxidative injury. Furthermore, evidence from human studies suggests that the development of insulin resistance during starvation may be linked to impaired mitochondrial function.

CONCLUSIONS

There is evidence from animal studies that short-term starvation causes mitochondrial dysfunction. Future studies should investigate whether mitochondrial dysfunction underlies the development of insulin resistance in patients undergoing elective surgery.

High selenium diet protects against TNBS-induced acute inflammation, mitochondrial dysfunction, and secondary necrosis in rat colon

OBJECTIVE

We studied the protective effects of selenium in a rat model of 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis to elucidate a possible mechanism of action.

METHOD

Rats were supplemented with sodium selenite for 21 d with a normal selenium diet (0.02 microg/g body weight), an intermediate selenium diet (ISD; 0.3 microg/g body weight), or a high selenium diet (HSD; 2 microg/g body weight). On day 22, colitis was induced with TNBS. Rats were sacrificed after 24 h and colonic tissue was removed for evaluation.

RESULTS

Selenium supplementation (HSD) resulted in a significant increase in selenium in colonic tissue. Morphologically, the HSD resulted in the preservation of tissue architecture and attenuated neutrophil infiltration; no vasculitis or necrosis was detected. Biochemically, the HSD decreased tissue myeloperoxidase activity and protected the mitochondria in the colon of TNBS-treated animals as evaluated by preserving tissue oxygen consumption, mitochondrial DNA, and expression of cytochrome c. The HSD increased levels of nuclear respiratory factor-1 and mitochondrial transcription factor-A in normal colon tissue and under inflammatory conditions. The ISD resulted in only a minor protective effect.

CONCLUSION

The results indicate that tissue damage in TNBS-induced colitis is accompanied by the arrest of mitochondrial respiration, loss of mitochondrial DNA, and the expression of nuclear-encoded mitochondrial proteins. Selenium effectively protects colon mitochondria by upregulation of the expression of mitochondrial transcription factors nuclear respiratory factor-1 and mitochondrial transcription factor-A. Selenium prevented inflammatory and necrotic changes after induction of colitis. Selenium in a high dose is therefore a potential therapeutic agent in inflammatory bowel disease.

Effect of feeding malnourished patients for 1 mo on mitochondrial complex I activity and nutritional assessment measurements

BACKGROUND

We showed previously that the activity of complex I (the first enzyme of the electron transport chain) in peripheral blood mononuclear cells decreases with malnutrition and increases to a subnormal value after 1 wk of refeeding, but the traditional markers of nutritional status do not do so.

OBJECTIVE

The aim of this study was to ascertain whether a period of nutritional intervention longer than 1 wk would normalize complex I activity and traditional markers of nutritional status.

DESIGN

Fifteen malnourished patients (7 women and 8 men) with > or =10% body weight loss over the previous 6 mo were studied on the day of their admission to hospital and 7, 14 and 30 d after the beginning of nutritional support. Complex I activity in peripheral blood mononuclear cells, weight, height, body composition, body water compartments, dietary intake, and serum albumin concentrations were measured on each occasion. The results before and during nutritional intervention were compared with values obtained in 30 healthy volunteers (17 women and 13 men).

RESULTS

Complex I activity increased significantly after the first week of refeeding (P < 0.001) and reached a normal value after 1 mo of nutritional supplementation. Among the classic markers of nutritional status, only the ratio of extracellular water to intracellular water tended to decrease over the refeeding period.

CONCLUSION

Complex I activity increases rapidly and is normalized by refeeding at a time when other markers of nutritional status do not change significantly.