Leptin in anorexia and cachexia syndrome

[Cancer-associated cachexia: an unresolved disease]

Cachexia is a systemic wasting condition associated to advanced phases of many cancers, which contributes to significant morbidity and mortality. It is mainly characterized by involuntary weight loss due to muscle wasting often associated with loss of adipose tissue, possibly leading to inanition and death, without treatment to date. Symptomatology covers a complex array of disorders (fatigue, inflammation, pain, anorexia, depression) related to multisystemic impairments progressively affecting numerous organs and tissues (muscle, adipose tissue, brain, immune system, gastrointestinal tract). The mechanisms of induction and progression of the disease, still poorly understood, involve inflammatory, metabolic, and neuroendocrine drivers, triggered by a variety of mediators originating from tumor, tumor-host interactions, and inter-organ crosstalk.

Metabolic underpinnings of cancer-related fatigue

Cancer-related fatigue (CRF) is one of the most prevalent and detrimental complications of cancer. Emerging evidence suggests that obesity and insulin resistance are associated with CRF occurrence and severity in cancer patients and survivors. In this narrative review, we analyzed recent studies including both preclinical and clinical research on the relationship between obesity and/or insulin resistance and CRF. We also describe potential mechanisms for these relationships, though with the caveat that because the mechanisms underlying CRF are incompletely understood, the mechanisms mediating the association between obesity/insulin resistance and CRF are similarly incompletely delineated. The data suggest that, in addition to their effects to worsen CRF by directly promoting tumor growth and metastasis, obesity and insulin resistance may also contribute to CRF by inducing chronic inflammation, neuroendocrinological disturbance, and metabolic alterations. Furthermore, studies suggest that patients with obesity and insulin resistance experience more cancer-induced pain and are at more risk of emotional and behavioral disruptions correlated with CRF. However, other studies implied a potentially paradoxical impact of obesity and insulin resistance to reduce CRF symptoms. Despite the need for further investigation utilizing interventions to directly elucidate the mechanisms of cancer-related fatigue, current evidence demonstrates a correlation between obesity and/or insulin resistance and CRF, and suggests potential therapeutics for CRF by targeting obesity and/or obesity-related mediators.

A Review of Olanzapine in the Treatment of Cancer Anorexia-Cachexia Syndrome

BACKGROUND

Cancer anorexia-cachexia syndrome (CAS) is a multifactorial condition that is highly prevalent in advanced cancer patients and associated with significant reduction in functional performance, reduction in quality of life, and increased mortality. Currently, no medications are approved for this indication. Recently, the American Society of Clinical Oncology (ASCO) released a rapid recommendation suggesting that low-dose olanzapine once daily may be used to treat cancer cachexia. Many questions still exist on how to use olanzapine for this indication in clinical practice. The objective of this review is to identify existing knowledge on the use of olanzapine for CAS.

METHODS

A comprehensive search was conducted to identify the primary literature that involved olanzapine for anorexia and cachexia in cancer patients between 2000 and 2023.

RESULTS

Seven articles were identified and are discussed here, including two randomized double-blinded placebo-controlled studies, one randomized comparative study, two prospective open-label studies, one retrospective chart review, and one case report.

CONCLUSIONS

Low dose olanzapine (2.5-5 mg once daily) may be useful in the treatment of CAS for increasing appetite, reducing nausea and vomiting, and promoting weight gain. Further large-scale multi-center randomized placebo-controlled studies will be needed to investigate the impact of olanzapine on weight change in CAS patients.

Cancer cachexia: Focus on cachexia factors and inter-organ communication

ABSTRACT

Cancer cachexia is a multi-organ syndrome and closely related to changes in signal communication between organs, which is mediated by cancer cachexia factors. Cancer cachexia factors, being the general name of inflammatory factors, circulating proteins, metabolites, and microRNA secreted by tumor or host cells, play a role in secretory or other organs and mediate complex signal communication between organs during cancer cachexia. Cancer cachexia factors are also a potential target for the diagnosis and treatment. The pathogenesis of cachexia is unclear and no clear effective treatment is available. Thus, the treatment of cancer cachexia from the perspective of the tumor ecosystem rather than from the perspective of a single molecule and a single organ is urgently needed. From the point of signal communication between organs mediated by cancer cachexia factors, finding a deeper understanding of the pathogenesis, diagnosis, and treatment of cancer cachexia is of great significance to improve the level of diagnosis and treatment. This review begins with cancer cachexia factors released during the interaction between tumor and host cells, and provides a comprehensive summary of the pathogenesis, diagnosis, and treatment for cancer cachexia, along with a particular sight on multi-organ signal communication mediated by cancer cachexia factors. This summary aims to deepen medical community's understanding of cancer cachexia and may conduce to the discovery of new diagnostic and therapeutic targets for cancer cachexia.

Cachexia: A systemic consequence of progressive, unresolved disease

Cachexia, a systemic wasting condition, is considered a late consequence of diseases, including cancer, organ failure, or infections, and contributes to significant morbidity and mortality. The induction process and mechanistic progression of cachexia are incompletely understood. Refocusing academic efforts away from advanced cachexia to the etiology of cachexia may enable discoveries of new therapeutic approaches. Here, we review drivers, mechanisms, organismal predispositions, evidence for multi-organ interaction, model systems, clinical research, trials, and care provision from early onset to late cachexia. Evidence is emerging that distinct inflammatory, metabolic, and neuro-modulatory drivers can initiate processes that ultimately converge on advanced cachexia.

Monitoring energy balance through clinical and serum biomarkers in patients with hematologic malignancies undergoing chemotherapy

Despite widespread concern about energy imbalance due to tumor and chemotherapy-related side effects, little is known about detailed variations in energy input, metabolic rate, and physical activity. This study explored changes in energy balance components and serum biomarkers of patients with hematologic malignancies undergoing chemotherapy. Our prospective study included 40 patients with hematologic malignancies hospitalized for chemotherapy. We measured energy balance components, physical function, and serum biomarkers at baseline and weekly after chemotherapy for 3 weeks. Significant weight loss, representing negative energy balance, occurred at 2 (p = 0.002) and 3 weeks (p < 0.001) post-chemotherapy. Statistically reduced oral intake was observed at 3 weeks post-chemotherapy (p = 0.040), and resting energy expenditure statistically decreased according to Harris-Benedict equation, but not to Penn State University equation. Physical function according to DEMMI score decreased significantly at 3 weeks post-chemotherapy (p = 0.002). Serum biomarker analysis demonstrated significant changes in albumin, total protein, CXCL13, and GDF15, with exception of leptin. Although conventional serum biomarkers (total protein and albumin) did not reach pathological states despite their statistical differences, subgroup analysis showed CXCL13 in weight loss group and GDF15 in reduced oral intake group were significantly changed. Over half of patients (65.0%, n = 26) suffered from energy imbalance associated with weight loss and reduced oral intake during chemotherapy. Serial laboratory results suggested that novel biomarkers (CXCL13, GDF15) could be correlated with cachexic state and reduced food intake. Monitoring clinical and serum biomarkers associated with energy balance together can help identify needs for nutritional support in patients with hematologic malignancies undergoing chemotherapy.

Cancer cachexia as a multiorgan failure: Reconstruction of the crime scene

Cachexia is a devastating syndrome associated with the end-stage of several diseases, including cancer, and characterized by body weight loss and severe muscle and adipose tissue wasting. Although different cancer types are affected to diverse extents by cachexia, about 80% of all cancer patients experience this comorbidity, which highly reduces quality of life and response to therapy, and worsens prognosis, accounting for more than 25% of all cancer deaths. Cachexia represents an urgent medical need because, despite several molecular mechanisms have been identified, no effective therapy is currently available for this devastating syndrome. Most studies focus on skeletal muscle, which is indeed the main affected and clinically relevant organ, but cancer cachexia is characterized by a multiorgan failure. In this review, we focus on the current knowledge on the multiple tissues affected by cachexia and on the biomarkers with the attempt to define a chronological pathway, which might be useful for the early identification of patients who will undergo cachexia. Indeed, it is likely that the inefficiency of current therapies might be attributed, at least in part, to their administration in patients at the late stages of cachexia.

Association between Leptin (G2548A) and Leptin Receptor (Q223R) Polymorphisms with Plasma Leptin, BMI, Stress, Sleep and Eating Patterns among the Multiethnic Young Malaysian Adult Population from a Healthcare University

Relative leptin resistance in childhood to absolute leptin resistance in maturity suggests sleep, eating behaviour, and the psychological state as probable causes. The current body of research provides inconclusive evidence linking G2548A and Q223R to obesity. Furthermore, we could find very little data that have observed the association between the environment and gene polymorphism, especially in the multiethnic population that exists in Malaysia. This study searched for a possible link between sleeping habits, eating behaviour, and stress indicators with plasma leptin and its genetic variation in young adult Malaysian healthcare students. The study involved 185 first- and second-year medical and dental students from a healthcare university. Polymerase Chain Reaction−Restriction Fragment Length Polymorphism(PCR-RFLP) determined the genotype, Enzyme Linked Immunoabsorbant Assay (ELISA) tested the serum leptin, and a self-administered questionnaire evaluated sleep, eating behaviour, and psychological condition. Gender and ethnicity are linked to fasting plasma leptin levels (p < 0.001). Plasma leptin also affects stress, anxiety, and sadness. Leptin (LEP) and Leptin Receptor (LEPR) polymorphisms were not associated with BMI, plasma leptin, sleep, eating behaviour, or psychological state. Young adult Malaysian Indians were obese and overweight, while Chinese were underweight. These findings imply overweight and obese participants were in stage I of leptin resistance and lifestyle change or leptin therapy could prevent them from becoming cripplingly obese as they age.

Understanding the molecular basis of anorexia and tissue wasting in cancer cachexia

Cancer cachexia syndrome is a major cause of morbidity and mortality in cancer patients in the advanced stage. It is a devastating disorder characterized by nutritional impairment, weakness, and wasting, and it affects treatment success and quality of life. Two major symptoms of cancer cachexia are anorexia and weight loss. Weight loss in cachexia is not reversed through increased food intake, suggesting that anorexia and weight loss in cancer patients are regulated by independent molecular mechanisms. Although the wasting phenotype mostly occurs in skeletal muscle and adipose tissue, other organs, such as the brain, liver, pancreas, heart, and gut, are also involved in cachexia. Thus, cachexia is a multiorgan syndrome. Although the molecular basis of cancer cachexia-induced weight loss is known, the mechanism underlying anorexia is poorly understood. Here, we highlight our recent discovery of a new anorexia mechanism by which a tumor-derived humoral factor induces cancer anorexia by regulating feeding-related neuropeptide hormones in the brain. Furthermore, we elucidated the process through which anorexia precedes tissue wasting in cachexia. This review article aims to provide an overview of the key molecular mechanisms of anorexia and tissue wasting caused by cancer cachexia.

Tumors can release factors that cause anorexia and weight loss in cancer patients, negatively impacting quality of life and treatment success. Patients with this condition, known as cachexia, can lose their appetite and be unable to gain weight even if they eat more. Although cancer cachexia directly causes the death of up to 20% of cancer patients, the mechanisms are poorly understood. Eunbyul Yeom and Kweon Yu at The Korea Research Institute of Bioscience and Biotechnology, Daejon, South Korea have reviewed the causes of cancer cachexia, highlighting their recent discovery that tumors produce a signaling molecule that induces anorexia by disrupting hunger signaling in the brain. Improving our understanding of the mechanisms underlying cancer cachexia may help in development of treatments.

Adipose Tissue and Cancer Cachexia: What Nurses Need to Know

The purpose of this article is to discuss the different types of adipose tissue involved in cachexia and describe their role in contributing to increased energy expenditure and negative energy balance. Armed with this knowledge, nurses will be better positioned to understand the clinical picture of cachexia, appreciate the rationale for proposed therapeutic interventions, and confidently dialogue with patients, families, and members of interdisciplinary health care teams about this prevalent condition.

A Leptin Receptor Antagonist Attenuates Adipose Tissue Browning and Muscle Wasting in Infantile Nephropathic Cystinosis-Associated Cachexia

Mice lacking the functional cystinosin gene (Ctns-/-), a model of infantile nephropathic cystinosis (INC), exhibit the cachexia phenotype with adipose tissue browning and muscle wasting. Elevated leptin signaling is an important cause of chronic kidney disease-associated cachexia. The pegylated leptin receptor antagonist (PLA) binds to but does not activate the leptin receptor. We tested the efficacy of this PLA in Ctns-/- mice. We treated 12-month-old Ctns-/- mice and control mice with PLA (7 mg/kg/day, IP) or saline as a vehicle for 28 days. PLA normalized food intake and weight gain, increased fat and lean mass, decreased metabolic rate and improved muscle function. It also attenuated perturbations of energy homeostasis in adipose tissue and muscle in Ctns-/- mice. PLA attenuated adipose tissue browning in Ctns-/- mice. PLA increased gastrocnemius weight and fiber size as well as attenuated muscle fat infiltration in Ctns-/- mice. This was accompanied by correcting the increased expression of muscle wasting signaling while promoting the decreased expression of myogenesis in gastrocnemius of Ctns-/- mice. PLA attenuated aberrant expressed muscle genes that have been associated with muscle atrophy, increased energy expenditure and lipolysis in Ctns-/- mice. Leptin antagonism may represent a viable therapeutic strategy for adipose tissue browning and muscle wasting in INC.

Approach to Patients with Unintentional Weight Loss

Unintentional weight loss is a common clinical problem with a broad differential diagnosis that is clinically important because of the associated risks of morbidity and mortality. Community-dwelling adults are often diagnosed with malignancy, nonmalignant gastrointestinal disorders, and psychiatric disorders as the cause of unintentional weight loss, whereas institutionalized older adults are diagnosed most often with psychiatric disorders. Up to a quarter of patients do not have a diagnosis after comprehensive workup, and close follow-up is warranted. Treatment involves management of underlying causes.

Asprosin is associated with anorexia and body fat mass in cancer patients

PURPOSE

Increasing evidence suggests that many adipokines are involved in cancer-related anorexia and cachexia syndrome (CACS), although the underlying mechanism remains to be clarify. Asprosin is a new peptide hormone mainly secreted by white adipose tissues that can increase appetite and body weight. In this cross-sectional study, we tested whether asprosin may intervene in the development of CACS.

METHODS

The fasting plasma asprosin levels were determined via enzyme-linked immune-sorbent assay. Anorexia was determined using the anorexia/cachexia subscale (A/CS) of the functional assessment of anorexia/cachexia therapy (FAACT) questionnaire. The body composition was assessed using bioelectrical impedance analysis. The association of plasma asprosin with anorexia, cachexia, and nutritional status was analyzed.

RESULTS

One hundred twenty treatment-naïve patients with pathological confirmed gastrointestinal or lung cancer and 14 mild gastritis patients were recruited. We found no significant difference in asprosin levels between subgroups of patients by age, sex, cancer types or stage. Correlation analysis suggested that asprosin levels were positively associated with body fat mass (r = 0.248, p = 0.043). No correlations were found between asprosin levels and hemoglobin, white blood cell count, blood platelet count, albumin, C-reactive protein, glucose, cholesterol, triglyceride, high density lipoprotein, low density lipoprotein, body mass index, body fat percentage, protein, skeletal muscle, muscle mass, lean body mass, and basal metabolic rate. Furthermore, asprosin levels were not significantly different between patients with or without cachexia. However, patients with anorexia had significantly lower asprosin levels compared with patients without anorexia. No significant difference in asprosin levels between gastritis and gastric cancer patients. Similarly, no significant change of asprosin levels occurred postoperatively in 10 gastric cancer patients.

CONCLUSIONS

Patients with anorexia had significantly lower asprosin levels compared with patients without anorexia. We therefore speculated that asprosin might intervene in the development of cancer anorexia and serve as a potential therapeutic target.

Adipocytes in Breast Cancer, the Thick and the Thin

It is well established that breast cancer development and progression depend not only on tumor-cell intrinsic factors but also on its microenvironment and on the host characteristics. There is growing evidence that adipocytes play a role in breast cancer progression. This is supported by: (i) epidemiological studies reporting the association of obesity with a higher cancer risk and poor prognosis, (ii) recent studies demonstrating the existence of a cross-talk between breast cancer cells and adipocytes locally in the breast that leads to acquisition of an aggressive tumor phenotype, and (iii) evidence showing that cancer cachexia applies also to fat tissue and shares similarities with stromal-carcinoma metabolic synergy. This review summarizes the current knowledge on the epidemiological link between obesity and breast cancer and outlines the results of the tumor-adipocyte crosstalk. We also focus on systemic changes in body fat in patients with cachexia developed in the course of cancer. Moreover, we discuss and compare adipocyte alterations in the three pathological conditions and the mechanisms through which breast cancer progression is induced.

Nonclassical Islet Peptides: Pancreatic and Extrapancreatic Actions

The pancreas has physiologically important endocrine and exocrine functions; secreting enzymes into the small intestine to aid digestion and releasing multiple peptide hormones via the islets of Langerhans to regulate glucose metabolism, respectively. Insulin and glucagon, in combination with ghrelin, pancreatic polypeptide and somatostatin, are the main classical islet peptides critical for the maintenance of blood glucose. However, pancreatic islets also synthesis numerous ‘nonclassical’ peptides that have recently been demonstrated to exert fundamental effects on overall islet function and metabolism. As such, insights into the physiological relevance of these nonclassical peptides have shown impact on glucose metabolism, insulin action, cell survival, weight loss, and energy expenditure. This review will focus on the role of individual nonclassical islet peptides to stimulate pancreatic islet secretions as well as regulate metabolism. In addition, the more recognised actions of these peptides on satiety and energy regulation will also be considered. Furthermore, recent advances in the field of peptide therapeutics and obesity-diabetes have focused on the benefits of simultaneously targeting several hormone receptor signalling cascades. The potential for nonclassical islet hormones within such combinational approaches will also be discussed.

Evaluation of the impact of cachexia on clinical outcomes in aggressive lymphoma

Cancer cachexia is a state of involuntary weight loss and altered body composition triggered by an underlying malignancy. We sought to correlate measures of cachexia with clinical outcomes in aggressive lymphomas and to identify biological pathways involved in the cachexia phenotype for possible druggable targets. Radiographic measures of cachexia were collected in a retrospective cohort of 109 patients with aggressive B-cell lymphoma and followed for clinical outcome. We found males with sarcopenia had reduced progression-free survival (5·4 vs. 72·3 months, P < 0·0005) and overall survival (OS; 30·2 months vs. not reached, NR, P = 0·02); males with adipopenia also had decreased OS (21·6 months vs. NR, P = 0·04). A trend for increased OS was observed in female sarcopenics only (32·8 months vs. NR, P = 0·08). Additionally, we analysed a prospective cohort of 14 patients for differences in circulating molecular targets involved in various biological pathways. There was a significant correlation with cachexia for reduced serum levels of mediators within the glucose utilization [insulin -like growth factor (IGF)-binding protein 6, P = 0·04; IGF-1, P = 0·02], inflammation (lymphotoxin-like inducible protein that competes with glycoprotein D for herpesvirus entry on T cells; LIGHT, P = 0·005), and energy intake/expenditure (leptin, P = 0·004). We conclude that cachexia in patients with aggressive lymphomas has sex-specific prognostic utility and correlates with measurable changes in metabolism and immune function.

Leptin and ghrelin in chronic kidney disease: their associations with protein-energy wasting

BACKGROUND

This study aimed to evaluate plasma concentrations of leptin and total ghrelin in children with chronic kidney disease (CKD) and assess their roles in protein-energy wasting (PEW).

METHODS

This study consisted of three different CKD populations [CKD group (20 patients with non-dialysis CKD), dialysis group (39 patients on dialysis), and kidney transplant (KTx) group (35 KTx recipients)] and control group (18 healthy children). Plasma leptin and total ghrelin levels were measured. Multi-frequency bioimpedance analysis was used for the assessment of fat and lean mass. PEW was defined using criteria including body mass, muscle mass, growth, serum albumin level, and protein intake.

RESULTS

While plasma leptin levels did not differ among the study groups, total ghrelin levels were significantly higher in the dialysis group (P < 0.001). Seven dialysis patients (18%) and one CKD patient (5%) but none of the KTx recipients met the criteria of PEW. Dialysis patients with PEW had lower plasma leptin levels compared to their counterparts (P = 0.018); however, total ghrelin levels did not differ between the two groups (P = 0.10). Low leptin level in dialysis patients was independently associated with lower fat mass index (P < 0.001) and lower height-specific SD scores of BMI (P = 0.019).

CONCLUSIONS

PEW is prevalent in dialysis patients. Low levels of leptin seem to be associated with PEW. Our result suggests that low leptin levels may be a consequence rather than a cause of PEW. Longitudinal studies are required to investigate this complex relationship between leptin and PEW in pediatric dialysis patients.

Skeletal muscle-gut axis: emerging mechanisms of sarcopenia for intestinal and extra intestinal diseases

In recent years, there has been an increasing interest on muscle wasting, considering the reduction of quality of life and the increase of morbidity and mortality associated. Sarcopenia and cachexia represent two conditions of reduction of muscle mass, sharing several elements involved in their pathogenesis, such as systemic inflammation, impaired muscle protein synthesis, increased muscle apoptosis, mitochondrial dysfunction in skeletal muscle tissue and insulin resistance. These features often characterize cancer, inactivity or denervation, but also inflammatory diseases, such as chronic obstructive pulmonary disease, renal failure, cardiac failure, rheumatoid arthritis, inflammatory bowel disease and aging in general. The gastrointestinal tract and gut microbiota are thought to be deeply associated with muscle function and metabolism, although the exact mechanisms that link gut with skeletal muscle are still not well known. This review summarized the potential pathways linking gut with muscle, in particular in conditions as sarcopenia and cachexia. The main emerging pathways implicated in the skeletal muscle-gut axis are: the myostatin/activin signaling pathway, the IGF1/PI3K/AKT/mTOR signaling pathway, which results suppressed, the NF-kB signaling pathway and the FOXO signaling pathway. Further researches in this field are necessary to better explain the linkage between gut microbiota and muscle wasting and the possible emerging therapies associated.

Novel herbal medicine LA16001 ameliorates cisplatin-induced anorexia

Chemotherapy frequently causes anorexia in cancer patients, which has been associated with poor disease prognosis. Several therapeutic strategies for the treatment of chemotherapy‑induced anorexia are available; however, their adverse effects limit their clinical use. Herbal medicines have a long history of use for the treatment of various diseases, including cancer, and recent research has demonstrated their safety and efficacy. In the present study, combinations of herbal medicines were designed based on traditional Korean medicine, and their effects were investigated on chemotherapy‑induced anorexia. Herbal mixtures were extracted, composed of Atractylodes japonica, Angelica gigas, Astragalus membranaceus, Lonicera japonica Thunb., Taraxacum platycarpum H. Dahlstedt and Prunella vulgaris var. asiatica (Nakai) Hara. The mixtures were termed LCBP‑Anocure‑16001‑3 (LA16001, LA16002, LA16003). A cisplatin‑induced anorexic mouse model was used to evaluate the putative effects of the extracts on chemotherapy‑induced anorexia. Treatment with LA16001 was revealed to prevent body weight loss, and all three extracts were demonstrated to improve food intake. When the molecular mechanisms underlying the orexigenic effects of LA16001 were investigated, altered expression levels of ghrelin, leptin and interleukin‑6 were revealed. Furthermore, LA16001 was reported to induce phosphorylation of Janus kinase 1 and signal transducer and activator of transcription 3. In addition, LA16001 administration increased the number of white blood cells and neutrophils. These results suggested that the herbal formula LA16001 may be able to prevent chemotherapy‑induced anorexia and may have potential as a novel therapeutic strategy for the adjuvant treatment of patients with cancer.

The Role of Essential Fatty Acids in Anorexia Nervosa and Obesity

The two basic questions in food intake study are what we eat, and how much do we eat. Most research is directed toward the control of how much is eaten. This is likely the result of the increased number of individuals with eating disorders in the Western world. Feeding behavior is highly complex, and is controlled by many psychological, physiological, biochemical, and immunological factors. The aim of this review is to clarify the involvement of fatty acids in eating disorders such as anorexia and binge eating disorder. The review will describe the modified fatty acid profile observed in individuals with anorexia or binge eating disorder, and discuss on what factors fatty acids can exert beneficial effects. In addition, the differences and similarities between anorexia and binge eating disorder will be discussed. We suggest that beneficial effects of essential fatty acids on both anorexia and binge eating disorder can be explained by the stabilizing effect of those fatty acids on the neuronal membrane fluidity index.

Cancer anorexia: hypothalamic activity and its association with inflammation and appetite-regulating peptides in lung cancer

BACKGROUND

Energy homeostasis is mediated by the hypothalamus, whose inflammation-induced functional derangements contribute to the onset of anorexia in cancer. By using functional magnetic resonance imaging (fMRI), we determined the patterns of hypothalamic activation after oral intake in anorexic (A), non-anorexic (NA) cancer patients, and in controls (C).

METHODS

Lung cancer patients were considered. Hypothalamic activation was recorded in A and NA patients and in C by fMRI, before (T0), immediately after (T1) the administration of an oral nutritional supplement, and after 15 min (T2). The grey of the hypothalamus and Blood Oxygen Level Dependent (BOLD) intensity were calculated and normalized for basal conditions. Interleukin (IL)-1, IL-6, tumour necrosis factor (TNF)-α, ghrelin, and leptin plasma levels were measured. A statistical parametric mapping was used.

RESULTS

Thirteen lung cancer patients (7 M, 6 F; 9A, 4NA) and 2 C (1 M, 1 F) were enrolled. Controls had the lowest BOLD intensity. At all-time points, anorexic patients showed lower hypothalamic activity compared with NA (P < 0.001) (T0: 585.57 ± 55.69 vs. 667.92 ± 33.18, respectively; T1: 536.50 ± 61.70 vs. 624.49 ± 55.51, respectively; T2: 556.44 ± 58.51 vs. 615.43 ± 71.50, respectively). Anorexic patients showed greater BOLD signal reduction during T0-T1 than NA (-8.5% vs. -6.80%, P < 0.001). Independently from the presence of anorexia, BOLD signals modification before and after oral challenge correlated with basal values of IL-1 and ghrelin (P < 0.001).

CONCLUSIONS

Hypothalamic activity in A cancer patients is reduced respect to NA and responds differently to oral challenges. This suggests a central control of appetite dysregulation during cancer anorexia, before, and after oral intake.

Efficacy of preoperative immunonutrition in locally advanced pancreatic cancer undergoing irreversible electroporation (IRE)

BACKGROUND

Improved preoperative immunonutrition has been shown to decrease the length of stay (LOS) and complications among patients undergoing elective gastrointestinal cancer surgeries. The purpose of this study was to determine whether preoperative immunonutrition supplementation decreases postoperative LOS, infectious complications, and morbidity in patients undergoing irreversible electroporation (IRE) surgery for locally advanced pancreatic cancer (LAPC).

METHODS

At a regional hepatopancreatobiliary referral center within an academic medical center 71 patients receiving IRE treatment of LAPC were included in the study. The participants were divided into those receiving preoperative immunonutrition (n = 44) and those receiving no supplemental preoperative immunonutrition (n = 27). Main outcomes and measures were LOS, postoperative complications, nutritional risk index (NRI), and albumin levels.

RESULTS

Patients in both groups were similar for preoperative nutrition parameters and operative therapy. Patients in the immunonutrition group experienced a statistically significant decrease in postoperative complications (p = 0.05) and LOS (10.7 vs. 17.4, p = 0.01), and less of a decrease in nutritional risk index (-12.6 vs. -16.2, p = 0.03) and albumin levels (-1.1 vs. -1.5, p < 0.01).

CONCLUSION

Preoperative immunonutrition was clinically significant in decreasing postoperative complications, LOS, and improving post-surgery NRI and albumin levels in patients receiving elective IRE treatment of non-resectable pancreatic cancer. These results indicate that preoperative immunonutrition is effective and feasible in this subset of cancer patients.

Orosomucoid as prognosis factor associated with inflammation in acute or nutritional status in chronic heart failure

BACKGROUND

Inflammation and nutritional state are involved in the pathogenesis of heart failure (HF).

OBJECTIVE

To study the contribution of alpha-1-acid-glycoprotein (AGP) to these factors and its prognostic value in acute (AHF) or chronic HF (CHF).

METHODS

The observational study has included 147 patients (mean age 70years, 62% men) admitted to a cardiology department for HF and followed-up for an average 326.6±140.8days. Blood AGP values were measured by Enzyme-Linked ImmunoSorbent Assay. Monocytes subsets were determined with CD14 and CD16 antibodies by flow cytometry and body composition was measured by dual-energy X-ray absorptiometry. The regulation of tumor necrosis factor (TNF-α) and leptin by AGP in epicardial adipose tissue (EAT) were analyzed by real time polymerase chain reaction.

RESULTS

High AGP, that was associated with CD14⁺CD16⁺ monocytes, and proBNP levels at the discharge were indicators of rehospitalization for HF in AHF patients. However, low AGP levels determined a worse nutritional state in CHF patients. The leptin levels were downregulated by high AGP concentration in epicardial fat.

CONCLUSION

AGP is a dual indicator in HF because high levels are predictors of adverse outcomes in AHF but low levels are related to the worse nutritional status in CHF. The regulation of leptin by AGP in epicardial fat might suggest a new pathway as protective mechanism in CHF.

Plasma Leptin Levels and Risk of Incident Cancer: Results from the Dallas Heart Study

Purpose

Leptin dysregulation has been postulated to affect cancer risk through its effects on obesity and inflammation. Epidemiological data evaluating this relationship are conflicting and studies in non-white cohorts is lacking. Therefore, we examined the association of leptin with the risk of incident cancer in the multiethnic Dallas Heart Study (DHS).

Methods

Participants enrolled in the DHS without prevalent cancer and with baseline leptin measurements were included. Incident cancer cases were identified through a systematic linkage of the DHS and the Texas Cancer Registry. Leptin was evaluated both as a continuous variable and in sex-specific quartiles. Multivariable Cox proportional hazards modeling was performed to examine the association between leptin levels with incident cancer after adjusting for age, sex, race, smoking status, alcohol use, family history of malignancy, body mass index (BMI), diabetes mellitus and C-reactive protein.

Results

Among 2,919 participants (median age 44 years; 54% women; 70% nonwhite; median BMI 29.4 kg/m²), 190 (6.5%) developed cancer after median follow- up of 12 years. Median leptin levels were 12.9 (interquartile range [IQR] 5.8–29.5) ng/ml in the incident cancer group vs. 12.3 (IQR 5.4–26.4) ng/ml those without an incident cancer (p = 0.34). Leptin was not associated with cancer incidence in multivariable analysis (unit standard deviation increase in log-transformed leptin, hazard ratio 0.95; 95% confidence interval, 0.77–1.16; p = 0.60). No association was observed in analyses stratified by sex, race/ethnicity, diabetes, or obesity status.

Conclusions

In this study of a predominantly minority population, no association between premorbid leptin levels and cancer incidence was demonstrated. Despite preclinical rationale and positive findings in other studies, this association may not replicate across all racial/ethnic populations.

Serum Leptin Is a Biomarker of Malnutrition in Decompensated Cirrhosis

Background and Aims

Malnutrition is a leading cause of morbidity and mortality in cirrhosis. There is no consensus as to the optimal approach for identifying malnutrition in end-stage liver disease. The aim of this study was to measure biochemical, serologic, hormonal, radiographic, and anthropometric features in a cohort of hospitalized cirrhotic patients to characterize biomarkers for identification of malnutrition.

Design

In this prospective observational cohort study, 52 hospitalized cirrhotic patients were classified as malnourished (42.3%) or nourished (57.7%) based on mid-arm muscle circumference < 23 cm and dominant handgrip strength < 30 kg. Anthropometric measurements were obtained. Appetite was assessed using the Simplified Nutrition Appetite Questionnaire (SNAQ) score. Fasting levels of serum adipokines, cytokines, and hormones were determined using Luminex assays. Logistic regression analysis was used to determine features independently associated with malnutrition.

Results

Subjects with and without malnutrition differed in several key features of metabolic phenotype including wet and dry BMI, skeletal muscle index, visceral fat index and HOMA-IR. Serum leptin levels were lower and INR was higher in malnourished subjects. Serum leptin was significantly correlated with HOMA-IR, wet and dry BMI, mid-arm muscle circumference, skeletal muscle index, and visceral fat index. Logistic regression analysis revealed that INR and log-transformed leptin were independently associated with malnutrition.

Conclusions

Low serum leptin and elevated INR are associated with malnutrition in hospitalized patients with end-stage liver disease.

Inflammation and nutrition in children with chronic kidney disease

Chronic inflammation and nutritional imbalance are important comorbid conditions that correlate with poor clinical outcomes in children with chronic kidney disease (CKD). Nutritional disorders such as cachexia/protein energy wasting, obesity and growth retardation negatively impact the quality of life and disease progression in children with CKD. Inadequate nutrition has been associated with growth disturbances in children with CKD. On the other hand, over-nutrition and obesity are associated with poor outcomes in children with CKD. The exact mechanisms leading to these unfavorable conditions are not fully elucidated and are most likely multifactorial. In this review, we focus on the pathophysiology of nutrition disorders and inflammation and their impact on clinical outcomes in children with CKD.

Sip-jeon-dea-bo-tang, a traditional herbal medicine, ameliorates cisplatin-induced anorexia via the activation of JAK1/STAT3-mediated leptin and IL-6 production in the fat tissue of mice

Despite its therapeutic advantages, chemotherapy can also cause adverse effects, including anorexia and loss of appetite. Although numerous patients with cancer have been reported to suffer from anorexia during or following chemotherapy, treatment options for anorexia remain to be determined. In Asian countries, traditional medicines are widely used to treat problems with appetite; sip-jeon-dea-bo-tang (SJDBT) is one of those medicines used for the treatment of anorexia. The present study demonstrated that SJDBT ameliorated cisplatin-induced anorexia. In a mouse model of chemotherapy-induced anorexia, oral administration of SJDBT prevented the cisplatin-induced reduction of food intake, inhibiting weight loss. The results of multiplex assays showed that SJDBT only altered the levels of interleukin (IL)-6 and leptin in the serum and fat tissue. In addition, SJDBT maintained the serum leptin level and increased the serum IL-6 level, whereas cisplatin reduced the levels of both serum leptin and IL-6. Furthermore, SJDBT was revealed to increase the levels of leptin and IL-6 in the fat tissue by activating the JAK1/STAT3 signaling pathway. In conclusion, the present results revealed that SJDBT ameliorated cisplatin-induced anorexia, suggesting its usefulness in the prevention of anorexia during chemotherapy.

Systematic review of peri-operative nutritional support for patients undergoing hepatobiliary surgery

BACKGROUND

Malnutrition is prevalent among peri-operative patients undergoing hepatobiliary surgery and is an important prognostic factor. Both hepatobiliary disease and surgical trauma significantly affects body's metabolism and environment. Therefore, it is very important for patients with liver diseases undergoing hepatobiliary surgery to receive essential nutritional support during peri-operative period.

METHODS

We summarized our clinical experience and reviewed of related literature to find the way for implementing the appropriate nutritional strategy.

RESULTS

We found after comprehensively evaluating nutrition status, function of liver and gastrointestinal tract, nutritional strategy would be selected correctly. In severe malnutrition, initiation of enteral nutrition (EN) and/or parenteral nutrition (PN) with essential or special formulae is often recommended. Especially nasojejunal feeding is indicated that early application can improve nutritional status and liver function, reduce complications and prolong survival.

CONCLUSIONS

The reasonable peri-operative nutritional support therapy can improve the effect of surgical treatment and promote the patients' recovery.

Advances in pharmacologic strategies for cancer cachexia

INTRODUCTION

Cancer cachexia is a severe inflammatory metabolic syndrome accounting for fatigue, an impairment of normal activities and, eventually, death. The loss of muscle mass associated with body weight loss is the main feature of this syndrome.

AREAS COVERED

The present review aims to describe the advances in the pharmacological approaches for cancer cachexia, highlighting the impact on weight loss, muscle wasting and related outcomes.

EXPERT OPINION

Among the pharmacological agents, attention should yet be given to the currently most widely studied drugs, such as progestogens and NSAIDs. Emerging drugs, such as ghrelin and selective androgen receptor modulators, have obtained promising results in recent randomized clinical trials. Larger sample sizes and more robust data on the effectiveness of anti-cytokine agents are needed. Any pharmacological approach to counteract cancer cachexia should always be associated with an adequate caloric intake, obtained by diet or through enteral or parenteral supplementation, if indicated. Finally, we can currently state that a combined approach that simultaneously targets the fundamental pathways involved in the pathogenesis of cancer cachexia is likely to be the most effective in terms of improvements in body weight as well as muscle wasting, function, physical performance and quality of life.

Effect of bariatric surgery on humoral control of metabolic derangements in obese patients with type 2 diabetes mellitus: How it works

Obesity and diabetes is a co-pandemic and a major health concern that is expanding. It has many psychosocial and economic consequences due to morbidity and mortality of this disease combination. The pathophysiology of obesity and related diabetes is complex and multifactorial. One arm of this disease process is the genetic susceptibility. Other arm is dependent on the intricate neuro-humoral factors that converge in the central nerve system. Gut hormones and the adipose tissue derived factors plays an important role in this delicate network. Bariatric surgery provides the only durable option for treatment of obesity and furthermore it provides a remission in the concomitant diseases that accompany obesity. This review provides a brief insight to all these mechanisms and tries to deduce the possible reasons of remission of type 2 diabetes after bariatric surgery.

Immune-metabolic profiling of anorexic patients reveals an anti-oxidant and anti-inflammatory phenotype

CONTEXT

Anorexia nervosa (AN) is an excessive form of calorie restriction (CR) associated with pathological weight loss and alterations of the immune system. However, AN patients seem to be protected from common viral infections.

OBJECTIVES

To investigate the metabolic and molecular adaptations induced by sustained extreme CR in the peripheral blood mononuclear cells (PBMCs) of patients with restrictive alimentary AN.

DESIGN

Inflammatory cytokines and adipokines were measured in 15 young (age range, 15-24 years) AN female patients and 20 age-matched healthy controls. Isolated PBMCs were immunophenotyped by flow cytometry, and glycolysis and mitochondrial respiration were determined by measuring the extracellular acidification and oxygen consumption rate. Stress resistance to H2O2 and the antioxidant transcriptional profile of PBMCs and human fibroblasts incubated with sera from AN patients were also determined.

RESULTS

Compared with controls, AN patients (BMI, 15.9±0.4 kg/m(2)) had significantly fewer leucocytes, lymphocytes and NK cells, lower serum concentrations of leptin, IGF-1 and sTNFR1, and higher levels of adiponectin, sCD40L and sICAM-1 (p<0.05). IL-1β, TNFα, and IL-6 produced by PBMC cultured with autologous serum for 48 h were significantly lower in AN patients than in controls (p<0.01). Moreover, glycolysis and mitochondrial respiration were lower, and the antioxidant transcriptional profile was higher in the PBMCs of AN patients. Fibroblasts cultured in serum from AN patients showed a 24% increase in resistance to H2O2 damage.

CONCLUSIONS

Extreme CR in AN patients is associated with a reduction in several immune cell populations, but with higher antioxidant potential, stress resistance and an anti-inflammatory status.

Could the improvement of obesity-related co-morbidities depend on modified gut hormones secretion?

Obesity and its associated diseases are a worldwide epidemic disease. Usual weight loss cures - as diets, physical activity, behavior therapy and pharmacotherapy - have been continuously implemented but still have relatively poor long-term success and mainly scarce adherence. Bariatric surgery is to date the most effective long term treatment for morbid obesity and it has been proven to reduce obesity-related co-morbidities, among them nonalcoholic fatty liver disease, and mortality. This article summarizes such variations in gut hormones following the current metabolic surgery procedures. The profile of gut hormonal changes after bariatric surgery represents a strategy for the individuation of the most performing surgical procedures to achieve clinical results. About this topic, experts suggest that the individuation of the crosslink among the gut hormones, microbiome, the obesity and the bariatric surgery could lead to new and more specific therapeutic interventions for severe obesity and its co-morbidities, also non surgical.

Obesity-mediated regulation of HGF/c-Met is associated with reduced basal-like breast cancer latency in parous mice

It is widely thought that pregnancy reduces breast cancer risk, but this lacks consideration of breast cancer subtypes. While a full term pregnancy reduces risk for estrogen receptor positive (ER+) and luminal breast cancers, parity is associated with increased risk of basal-like breast cancer (BBC) subtype. Basal-like subtypes represent less than 10% of breast cancers and are highly aggressive, affecting primarily young, African American women. Our previous work demonstrated that high fat diet-induced obesity in nulliparous mice significantly blunted latency in C3(1)-T_Ag mice, a model of BBC, potentially through the hepatocyte growth factor (HGF)/c-Met oncogenic pathway. Experimental studies have examined parity and obesity individually, but to date, the joint effects of parity and obesity have not been studied. We investigated the role of obesity in parous mice on BBC. Parity alone dramatically blunted tumor latency compared to nulliparous controls with no effects on tumor number or growth, while obesity had only a minor role in further reducing latency. Obesity-associated metabolic mediators and hormones such as insulin, estrogen, and progesterone were not significantly regulated by obesity. Plasma IL-6 was also significantly elevated by obesity in parous mice. We have previously reported a potential role for stromal-derived hepatocyte growth factor (HGF) via its cognate receptor c-Met in the etiology of obesity-induced BBC tumor onset and in both human and murine primary coculture models of BBC-aggressiveness. Obesity-associated c-Met concentrations were 2.5-fold greater in normal mammary glands of parous mice. Taken together, our studies demonstrate that, parity in C3(1)-T_Ag mice dramatically reduced BBC latency compared to nulliparous mice. In parous mice, c-Met is regulated by obesity in unaffected mammary gland and is associated with tumor onset. C3(1)-T_Ag mice recapitulate epidemiologic findings such that parity drives increased BBC risk and potential microenvironmental alterations in c-Met signaling may play a role in etiology.

Evaluation of leptin, interleukin-1 beta and tumor necrosis factor alpha in serum of malaria patients as prognostic markers of treatment outcome

OBJECTIVE

To analyze serum leptin levels in patients with malaria falciparum and compare them with healthy controls and correlate with development and outcome of malaria infection.

METHODS

Sixty cases of malaria falciparum were included in this study as patients. Thirty healthy individuals of comparable age, racial and body mass index were taken as controls. All patients were diagnosed by clinical picture and the presence of malaria parasites in blood film. Estimation of liver function test, kidney function test, complete blood count, fasting blood sugar, fasting serum insulin, pro-inflammatory cytokine tumor necrosis factor alpha (TNFα) and interleukin 1 (IL1), estimation of morning serum leptin and calculation of body mass index (kg/m(2)) were done in both groups on the day of admission, on discharge and 7 d after discharge.

RESULTS

At admission, leptin levels were significantly higher in patients group than in control while fasting serum insulin levels were not significantly different between the two groups. There were significant increases as regard to TNFα and IL1 in malaria patients. Significant differences were observed between the control and the patient group for leptin, TNFα and IL1 at the time of admission and discharge. After discharge for 7 d, a significant decline in serum leptin levels, TNFα and IL1 in the patients group was observed as compared with time of admission and time of discharge, a positive correlation between serum leptin levels and TNFα and IL1.

CONCLUSIONS

Leptin hormone level might play an important role in development and outcome of malaria infection.

Circulating inflammatory cytokines and adipokines are associated with increased risk of Barrett's esophagus: a case-control study

BACKGROUND & AIMS

Obesity is associated with Barrett's esophagus (BE) and with changes in circulating levels of adipokines (leptin and adiponectin) and cytokines. Although studies have reported that adipokines and inflammatory cytokines are necessary for the development of BE, their role is controversial.

METHODS

We performed a case-control study; cases (n = 141) were patients who underwent esophagogastroduodenoscopy and were found to have BE, which was based on endoscopy and histology, and controls (n = 139) were primary care patients eligible for screening colonoscopies who agreed to undergo esophagogastroduodenoscopy. We examined the association between BE and circulating levels of adipokines and cytokines (interleukin [IL]-1β, IL-6, IL-8, IL-10, and IL-12p70; tumor necrosis factor-α; and interferon-γ). Cases and controls were compared by calculating odds ratios (ORs) and 95% confidence intervals (CIs) and using unadjusted and multiple logistic regression, adjusting for age, sex, race, waist-hip ratio, use of proton pump inhibitors and nonsteroidal anti-inflammatory drugs, and Helicobacter pylori infection.

RESULTS

The adjusted ORs for BE were 2.62 (95% CI, 1.0-6.8), 5.18 (95% CI, 1.7-15.7), and 8.02 (95% CI, 2.79-23.07) for the highest quintile vs the lowest quintile of levels of IL-12p70, IL-8, and leptin, respectively, but the OR was not significant for IL-6 (2.39; 95% CI, 0.84-6.79). The adjusted OR for BE was 0.14 for highest quintile of IL-10 compared with lowest quintile (95% CI, 0.05-0.35) and 0.03 for IL-1β ≥ median vs none detected (95% CI, 0.006-0.13). Higher levels of IL-8 and leptin and lower levels of IL-10 and IL-1β were associated with the presence of long-segment (≥3 cm) and short-segment BE. There were no differences between cases and controls in levels of interferon-γ, tumor necrosis factor-α, adiponectin, or insulin.

CONCLUSIONS

BE is associated with circulating inflammatory cytokines and leptin and low levels of anti-inflammatory cytokines. These findings could partly explain the effect of obesity on BE.

Role of HGF in obesity-associated tumorigenesis: C3(1)-TAg mice as a model for human basal-like breast cancer

Obesity is associated with basal-like breast cancer (BBC), an aggressive breast cancer subtype. The objective of this study was to determine whether obesity promotes BBC onset in adulthood and to evaluate the role of stromal-epithelial interactions in obesity-associated tumorigenesis. We hypothesized that hepatocyte growth factor (HGF) plays a promoting role in BBC, which express the HGF receptor, c-Met. In C3(1)-T(Ag) mice, a murine model of BBC, we demonstrated that obesity leads to a significant increase in HGF secretion and an associated decrease in tumor latency. By immunohistochemical analysis, normal mammary gland exhibited obesity-induced HGF, c-Met and phospho-c-Met, indicating that the activation of the cascade was obesity-driven. HGF secretion was also increased from primary mammary fibroblasts isolated from normal mammary glands and tumors of obese mice compared to lean. These results demonstrate that obesity-induced elevation of HGF expression is a stable phenotype, maintained after several passages, and after removal of dietary stimulation. Conditioned media from primary tumor fibroblasts from obese mice drove tumor cell proliferation. In co-culture, neutralization of secreted HGF blunted tumor cell migration, further linking obesity-mediated HGF-dependent effects to in vitro measures of tumor aggressiveness. In sum, these results demonstrate that HGF/c-Met plays an important role in obesity-associated carcinogenesis. Understanding the effects of obesity on risk and progression is important given that epidemiologic studies imply a portion of BBC could be eliminated by reducing obesity.

[Nutritional abnormalities in chronic obstructive pulmonary disease]

Nutritional abnormalities are associated with chronic obstructive pulmonary disease with a frequency ranging from 2 to 50%, depending on the geographical area and the study design. Diagnostic tools include anthropometry, bioelectrical impedance, dual energy radioabsortiometry and deuterium dilution, being the body mass and the lean mass indices the most frequently used parameters. While the most important consequences of nutritional abnormalities are muscle dysfunction and exercise limitation, factors implicated include an imbalance between caloric intake and consumption, and between anabolic and catabolic hormones, inflammation, tobacco smoking, poor physical activity, hypoxemia, some drugs and aging/comorbidities. The most important molecular mechanism for malnutrition associated with chronic obstructive pulmonary disease appears to be the mismatching between protein synthesis and breakdown. Among the therapeutic measures proposed for these nutritional abnormalities are improvements in lifestyle and nutritional support, although the use of anabolic drugs (such as secretagogues of the growth hormone) offers a new therapeutic strategy.

Role of leptin resistance in the development of obesity in older patients

Obesity is a global epidemic associated with aging-like cellular processes; in both aging and obesity, resistance to hormones such as insulin and leptin can be observed. Leptin is a circulating hormone/cytokine with central and peripheral effects that is released mainly by subcutaneous white adipose tissue. Centrally, leptin controls food intake, energy expenditure, and fat distribution, whereas it controls (among several others) insulin sensitivity, free fatty acids (FFAs) oxidation, and lipolysis in the periphery. Aging is associated with important changes in both the distribution and the composition of adipose tissue. Fat is redistributed from the subcutaneous to the visceral depot and increased inflammation participates in adipocyte dysfunction. This redistribution of adipose tissue in favor of visceral fat influences negatively both longevity and healthy aging as shown in numerous animal models. These modifications observed during aging are also associated with leptin resistance. This resistance blunts normal central and peripheral functions of leptin, which leads to a decrease in neuroendocrine function and insulin sensitivity, an imbalance in energy regulation, and disturbances in lipid metabolism. Here, we review how age-related leptin resistance triggers metabolic disturbances and affects the longevity of obese patients. Furthermore, we discuss the potential impacts of leptin resistance on the decline of brown adipose tissue thermogenesis observed in elderly individuals.

Leptin in pediatrics: A hormone from adipocyte that wheels several functions in children

The protein leptin, a pleiotropic hormone regulates appetite and energy balance of the body and plays important roles in controlling linear growth, pubertal development, cardiovascular function, and immunity. Recent findings in the understanding of the structure, functional roles, and clinical significance of conditions with increased and decreased leptin secretion are summarized. Balance between leptin and other hormones is significantly regulated by nutritional status. This balance influences many organ systems, including the brain, liver, and skeletal muscle, to mediate the essential adaptation process. The aim of this review is to summarize the possible physiological functions of leptin and its signaling pathways during childhood and adolescence including control of food intake, energy regulation, growth and puberty, and immunity. Moreover, its secretion and possible roles in the adaptation process during different disease states (obesity, malnutrition, eating disorders, delayed puberty, congenital heart diseases and hepatic disorders) are discussed. The clinical manifestations and the successful management of patients with genetic leptin deficiency and the application of leptin therapy in other diseases including lipodystrophy, states with severe insulin resistance, and diabetes mellitus are discussed.