Effects of methylphenidate on weight gain and food intake in hypothalamic obesity

Acquired hypothalamic obesity: A clinical overview and update

Hypothalamic obesity (HO) is a rare and complex disorder that confers substantial morbidity and excess mortality. HO is a unique subtype of obesity characterized by impairment in the key brain pathways that regulate energy intake and expenditure, autonomic nervous system function, and peripheral hormonal signalling. HO often occurs in the context of hypothalamic syndrome, a constellation of symptoms that follow from disruption of hypothalamic functions, for example, temperature regulation, sleep-wake circadian control, and energy balance. Genetic forms of HO, including the monogenic obesity syndromes, often impact central leptin-melanocortin pathways. Acquired forms of HO occur as a result of tumours impacting the hypothalamus, such as craniopharyngioma, surgery or radiation to treat those tumours, or other forms of hypothalamic damage, such as brain injury impacting the region. Risk for severe obesity following hypothalamic injury is increased with larger extent of hypothalamic damage or lesions that contain the medial and posterior hypothalamic nuclei that support melanocortin signalling pathways. Structural damage in these hypothalamic nuclei often leads to hyperphagia, central insulin and leptin resistance, decreased sympathetic activity, low energy expenditure, and increased energy storage in adipose tissue, the collective effect of which is rapid weight gain. Individuals with hyperphagia are perpetually hungry. They do not experience fullness at the end of a meal, nor do they feel satiated after meals, leading them to consume larger and more frequent meals. To date, most efforts to treat HO have been disappointing and met with limited, if any, long-term success. However, new treatments based on the distinct pathophysiology of disturbed energy homeostasis in acquired HO may hold promise for the future.

SIOP PODC-adapted treatment guidelines for craniopharyngioma in low- and middle-income settings

Pediatric craniopharyngioma is a rare tumor with excellent survival but significant long-term morbidities due to the loco-regional tumor growth or secondary to its treatment. Visual impairment, panhypopituitarism, hypothalamic damage, and behavioral changes are among the main challenges. This tumor should be managed under the care of a multidisciplinary team to determine the optimum treatment within the available resources. This is particularly important for low middle-income countries where resources are variable. This report provides risk-stratified management guidelines for children diagnosed with craniopharyngioma in a resource-limited setting.

Treatment of hypothalamic obesity in people with hypothalamic injury: new drugs are on the horizon

Hypothalamic obesity (HO) is a complex and rare disorder affecting multiple regulatory pathways of energy intake and expenditure in the brain as well as the regulation of the autonomic nervous system and peripheral hormonal signaling. It can be related to monogenic obesity syndromes which often affect the central leptin-melanocortin pathways or due to injury of the hypothalamus from pituitary and hypothalamic tumors, such as craniopharyngioma, surgery, trauma, or radiation to the hypothalamus. Traditional treatments of obesity, such as lifestyle intervention and specific diets, are still a therapeutic cornerstone, but often fail to result in meaningful and sustained reduction of body mass index. This review will give an update on pharmacotherapies of HO related to hypothalamic injury. Recent obesity drug developments are promising for successful obesity intervention outcomes.

Clinical Significance of Plasma Leptin and Its Receptors mRNA Expression in Craniopharyngiomas: A Prospective Study

Craniopharyngioma (CP) is a benign tumor with a high rate of obesity and frequent recurrence. Moreover, the role of leptin/leptin receptors axis in obesity and the prognosis of CP is still unknown. Plasma leptin concentration and mRNA expression of leptin receptors were assessed in patients with CP. Moreover, the association between leptin/leptin receptors axis, weight-related outcomes, and progression-free survival (PFS) were explored in CP patients. Leptin receptors overexpressed in CP tumor tissue were compared to normal brain tissue (p < 0.05); compared to healthy controls, the concentration of leptin was elevated in CP with or without matched age, sex, and body mass index (BMI) (p < 0.05). The high plasma leptin level was an independent risk predictor for significant weight gain (adjusted odds ratio (aOR) = 2.29, and p = 0.030) and new-onset obesity (aOR = 6.64, and p = 0.016). High plasma leptin level (adjusted hazard ratio (aHR) = 3.74, and p = 0.011) and leptin receptor (LEPR) mRNA expression (aHR = 3.12, and p = 0.045) were independent risk factors for poor PFS in CP. Inappropriately elevated leptin relative to BMI and its failure to inhibit further weight gain indicate the existence of leptin resistance in patients with CP. Leptin and LEPR were independent predictors for PFS of patients with CP. The leptin/leptin receptors axis may be a potential therapeutic target for obesity in patients with CP.

Contemporary Biological Insights and Clinical Management of Craniopharyngioma

Craniopharyngiomas (CPs) are clinically aggressive tumors because of their invasive behavior and recalcitrant tendency to recur after therapy. There are 2 types based on their distinct histology and molecular features: the papillary craniopharyngioma (PCP), which is associated with BRAF-V600E mutations and the adamantinomatous craniopharyngioma (ACP), characterized by mutations in CTNNB1 (encoding β-catenin). Patients with craniopharyngioma show symptoms linked to the location of the tumor close to the optic pathways, hypothalamus, and pituitary gland, such as increased intracranial pressure, endocrine deficiencies, and visual defects. Treatment is not specific and mostly noncurative, and frequently includes surgery, which may achieve gross total or partial resection, followed by radiotherapy. In cystic tumors, frequent drainage is often required and intracystic instillation of drugs has been used to help manage cyst refilling. More recently targeted therapies have been used, particularly in PCP, but also now in ACP and clinical trials are underway or in development. Although patient survival is high, the consequences of the tumor and its treatment can lead to severe comorbidities resulting in poor quality of life, in particular for those patients who bear tumors with hypothalamic involvement. Accordingly, in these patients at risk for the development of a hypothalamic syndrome, hypothalamus-sparing treatment strategies such as limited resection followed by irradiation are recommended. In this review, we provide an update on various aspects of CP, with emphasis on recent advances in the understanding of tumor pathogenesis, clinical consequences, management, and therapies.

Approach to the Patient With Hypothalamic Obesity

Hypothalamic obesity (HO) is defined as abnormal weight gain due to physical destruction of the hypothalamus. Suprasellar tumors, most commonly craniopharyngiomas, are a classic cause of HO. HO often goes unnoticed initially as patients, families, and medical teams are focused on oncologic treatments and management of panhypopituitarism. HO is characterized by rapid weight gain in the first year after hypothalamic destruction followed by refractory obesity due to an energy imbalance of decreased energy expenditure without decreased food intake. Currently available pharmacotherapies are less effective in HO than in common obesity. While not a cure, dietary interventions, pharmacotherapy, and bariatric surgery can mitigate the effects of HO. Early recognition of HO is necessary to give an opportunity to intervene before substantial weight gain occurs. Our goal for this article is to review the pathophysiology of HO and to discuss available treatment options and future directions for prevention and treatment.

Combined methylphenidate and fluoxetine treatment in adolescent rats significantly impairs weight gain with minimal effects on skeletal development

Methylphenidate (MP) is frequently prescribed to treat Attention-Deficit/Hyperactivity Disorder (ADHD); however, many patients with ADHD experience depression and anxiety. As such, concomitant administration of selective serotonin reuptake inhibitors such as fluoxetine (FLX) is common. Our laboratory and others have shown that MP impairs skeletal development in preclinical and clinical settings, and FLX has also been linked to skeletal deficits. Unfortunately, little is known about the effects of combined MP and FLX treatment on skeletal development. The objective of this study was to investigate the effects of MP and FLX on bone morphology and biomechanical properties in adolescent rats. Four-week-old male Sprague-Dawley rats were randomly divided into the following 4 groups: Water, MP, FLX, and MP + FLX. As body weights in the MP, FLX, and MP + FLX groups were all lower than Water, the data were compared directly and after adjusting to body weight via linear regression. The direct comparison revealed that MP + FLX rats had significantly shorter (~12 %) and narrower femora and tibiae (~10 %) compared to most other groups, along with shorter (26-35 %), disorganized tibial growth plates. MicroCT analyses of the trabecular compartment of the proximal tibia identified reductions of 47 % for TV, 86 % for BV, 74 % for BV/TV, 68 % for Tb.N, 25 % in Tb.Th, and 74 % in vBMD concomitant with increases of 44 % for Tb.Sp for MP + FLX compared to Water. Similar analyses of femoral midshaft cortical bone identified reductions of 29 % for Ct.V, 30 % for Ps.V, 30 % for Ec. V, and 51 % for pMOI, as well as increases of 17 % for Ct.Th and 2 % for TMD for MP + FLX compared to Water. Biomechanically, MP + FLX femora were weaker, as indicated by a reduction in ultimate force (14 %) in MP + FLX compared to Water. The microstructural and biomechanical effects of MP + FLX were eliminated after adjustment for body weight, though the detrimental effects on growth plate morphology remained. We conclude that while the adverse microstructural and biomechanical effects of MP + FLX seen via direct comparison are predominantly attributable to reductions in body weight rather than direct effects on bone, MP and FLX, particularly in combination show detrimental effects on growth plate structure and chondrocyte morphology. These findings warrant further research into the effect of these drugs on weight gain, skeletal development and growth plate morphology, as well as consideration by physicians treating children and adolescents with ADHD.

Increased sperm DNA damage leads to poor embryo quality and subfertility of male rats treated with methylphenidate hydrochloride in adolescence

BACKGROUND

Methylphenidate hydrochloride (MPH) is a psychostimulant widely used in the treatment of attention deficit hyperactive disorder (ADHD), as well as a performance enhancer, for at least 60 years. Despite the notable effectiveness as a psychostimulant, ADHD is a chronic disorder and has a two-third chance of accompanying the individual throughout life. Long-term use of MPH has been associated not only with an increase in the development of neurodegenerative diseases, but it also has side effects on male fertility in experimental animals.

OBJECTIVES

To investigate whether methylphenidate poses a risk to sperm DNA structure and to the quality of embryos conceived after treatment during adolescence in rats.

MATERIALS AND METHODS

Wistar rats at 38 days of age were treated either with 5 mg/kg body weight of MPH, in a single daily dose for 30 days, via gavage or with distilled water-only protocol. Levels of oxidative stress in testicular and epididymal tissues were evaluated. Sperm chromatin quality and acrosome integrity was assessed under flow cytometry. From 107 days of age, animals were mated with untreated females. The effects of the paternal contribution at two different embryo development moments - cleavage stage (2.5 days post coitum) and late gestation (20 days post coitum) - were analyzed.

RESULTS

MPH caused high levels of sperm DNA damage, which was reflected in 40% of decrease in early embryo quality and a lower number of live pups at 20 dpc.

DISCUSSION

The high level of fragmentation seen in the embryos sired from the MPH group is consistent with the poor chromatin structure of the sperm, and does not seem to be a result of oxidative stress in the reproductive tissues.

CONCLUSIONS

The results presented here suggest that the subchronic use of MPH during male prepubertal phase may cause long term subfertility and compromise embryo survival. This article is protected by copyright. All rights reserved.

Novel Noninvasive Approaches to the Treatment of Obesity: From Pharmacotherapy to Gene Therapy

Recent insights into the pathophysiologic underlying mechanisms of obesity have led to the discovery of several promising drug targets and novel therapeutic strategies to address the global obesity epidemic and its comorbidities. Current pharmacologic options for obesity management are largely limited in number and of modest efficacy/safety profile. Therefore, the need for safe and more efficacious new agents is urgent. Drugs that are currently under investigation modulate targets across a broad range of systems and tissues, including the central nervous system, gastrointestinal hormones, adipose tissue, kidney, liver, and skeletal muscle. Beyond pharmacotherapeutics, other potential antiobesity strategies are being explored, including novel drug delivery systems, vaccines, modulation of the gut microbiome, and gene therapy. The present review summarizes the pathophysiology of energy homeostasis and highlights pathways being explored in the effort to develop novel antiobesity medications and interventions but does not cover devices and bariatric methods. Emerging pharmacologic agents and alternative approaches targeting these pathways and relevant research in both animals and humans are presented in detail. Special emphasis is given to treatment options at the end of the development pipeline and closer to the clinic (ie, compounds that have a higher chance to be added to our therapeutic armamentarium in the near future). Ultimately, advancements in our understanding of the pathophysiology and interindividual variation of obesity may lead to multimodal and personalized approaches to obesity treatment that will result in safe, effective, and sustainable weight loss until the root causes of the problem are identified and addressed.

Hypothalamic syndrome

Hypothalamic syndrome (HS) is a rare disorder caused by disease-related and/or treatment-related injury to the hypothalamus, most commonly associated with rare, non-cancerous parasellar masses, such as craniopharyngiomas, germ cell tumours, gliomas, cysts of Rathke's pouch and Langerhans cell histiocytosis, as well as with genetic neurodevelopmental syndromes, such as Prader-Willi syndrome and septo-optic dysplasia. HS is characterized by intractable weight gain associated with severe morbid obesity, multiple endocrine abnormalities and memory impairment, attention deficit and reduced impulse control as well as increased risk of cardiovascular and metabolic disorders. Currently, there is no cure for this condition but treatments for general obesity are often used in patients with HS, including surgery, medication and counselling. However, these are mostly ineffective and no medications that are specifically approved for the treatment of HS are available. Specific challenges in HS are because the syndrome represents an adverse effect of different diseases, and that diagnostic criteria, aetiology, pathogenesis and management of HS are not completely defined.

Craniopharyngiomas

Craniopharyngiomas are rare epithelial tumours situated primarily in the sellar/parasellar region, occurring along the path of the craniopharyngeal duct. Whilst classed as histologically benign tumours, their unpredictable growth pattern and proximity to vital structures including the optic chiasm, hypothalamus, and pituitary gland renders them a considerable threat, with significant associated morbidity and increase in mortality. Occurring both in child and adulthood, their clinical manifestations are broad, commonly with symptoms/signs secondary to hypothalamic-pituitary dysfunction, raised intracranial pressure and visual compromise. They have two distinct histological subtypes (adamantinomatous and papillary), with unique patterns of age distribution, and genetic and molecular make-up. With increasing understanding of their genetic pathogenesis including BRAF V600E mutations in the papillary subtype, and β-catenin mutations in the adamantinomatous, further research provides hope for the discovery of targeted medical therapy that can exploit molecular changes occurring as a result of such alterations. Until then, primary treatment consists of surgery with or without radiotherapy, with intracystic aspiration, chemotherapy or irradiation being alternative options in selected patients. Long term management by an experienced multidisciplinary team is essential, given the breadth of complications, including hypothalamic morbidity, visual compromise, cognitive and neuropsychological sequelae and impairment to quality of life.

Childhood-onset Craniopharyngioma

Craniopharyngiomas are rare embryonic malformational tumors of the sellar/parasellar region, classified by the World Health Organization (WHO) as tumors with low-grade malignancy (WHO I). The childhood adamantinomatous subtype of craniopharyngioma is usually cystic with calcified areas. At the time of diagnosis, hypothalamic/pituitary deficits, visual disturbances, and increased intracranial pressure are major symptoms. The treatment of choice in case of favorable tumor location (without hypothalamic involvement) is complete resection. It is important to ensure that optical and hypothalamic functionality are preserved. In case of unfavorable tumor location, that is with hypothalamic involvement, a hypothalamus-sparing surgical strategy with subsequent local irradiation of residual tumor is recommended. In the further course of the disease, recurrences and progression often occur. Nevertheless, overall survival rates are high at 92%. Severe impairment of quality of life and comorbidities such as metabolic syndrome, hypothalamic obesity, and neurological consequences can be observed in patients with disease- and/or treatment-related lesions of hypothalamic structures. Childhood-onset craniopharyngioma frequently manifests as a chronic disease so that patients require lifelong, continuous care by experienced multidisciplinary teams to manage clinical and quality of life consequences. For this review, a search for original articles and reviews published between 1986 and 2020 was performed in Pubmed, Science Citation Index Expanded, EMBASE, and Scopus. The search terms used were "craniopharyngioma, hypothalamus, pituitary obesity, irradiation, neurosurgery.

Management of Hypothalamic Obesity

Energy homeostasis, appetite, and satiety are modulated by a complex neuroendocrine system regulated by the hypothalamus. Dysregulation of this system resulting in hypothalamic obesity (HO) is caused by brain tumors, neurosurgery, and/or cranial irradiation. Craniopharyngioma (CP) is a paradigmatic disease with regard to the development of HO. Initial hypothalamic involvement of CP and/or treatment-related damage to hypothalamic-pituitary axes result in HO. Attempts to control HO with lifestyle interventions have not been satisfactory. No generally accepted pharmacologic or bariatric therapy for HO in CP has been effective in randomized controlled trials. Accordingly, prevention of HO is recommended.

Methylphenidate improves weight control in childhood brain tumor survivors with hypothalamic obesity

BACKGROUND

Hypothalamic obesity causes unrelenting weight gain for childhood brain tumor survivors. No single therapy has proven effective for treatment. We aimed to evaluate effectiveness of long-term methylphenidate therapy on body mass index (BMI) change in children with hypothalamic obesity.

METHODS

A retrospective analysis included children with a history of brain tumor and hypothalamic obesity receiving methylphenidate (10-60 mg/day) for hypothalamic obesity. Subjects were evaluated for BMI trajectory before and after methylphenidate start. Given that z-scores can be skewed in severely obese children, we calculated BMI as a percent of the BMI at the 95th percentile for the child's age and gender (BMI% 95th).

RESULTS

Twelve patients with hypothalamic obesity completed methylphenidate therapy for at least 6 months (median 3.1 years, range 1.0-5.8 years). All subjects had a suprasellar tumor (nine [75%] with craniopharyngioma) and pituitary dysfunction. Pretreatment median BMI percent of the 95th percentile was 125.6% (interquartile range [IQR] 25-75: 115.3-138.3%) with BMI z-score of 2.4 (IQR 25-75: 2.1-2.6). Following methylphenidate treatment, there was a 69.9% reduction in the median slope of BMI change. Eleven of 12 patients (92%) had a reduction in the slope of their BMI change on methylphenidate treatment. Postmethylphenidate median BMI percent of the 95th percentile decrease to 115.2% (IQR 25-75: 103.6-121.2%) with median BMI z-score of 2.1 (IQR 25-75: 1.8-2.2). Mild side effects were noted in six patients.

CONCLUSIONS

Methylphenidate use reduced and sustained BMI change in children with hypothalamic obesity. Stimulant therapy is an effective first-line agent for treatment of hypothalamic obesity.

Brief and extended abstinence from chronic oral methylphenidate treatment produces reversible behavioral and physiological effects

Methylphenidate (MP) is a commonly prescribed psychostimulant to individuals with Attention Deficit Hyperactivity Disorder, and is often used illicitly among healthy individuals with intermittent breaks to coincide with breaks from school. This study examined how intermittent abstinence periods impact the physiological and behavioral effects of chronic oral MP self-administration in rats, and whether these effects persist following prolonged abstinence from the drug. Rats were treated orally with water, low-dose (LD), or high-dose (HD) MP, beginning at PND 28. This daily access continued for three consecutive weeks followed by a 1-week abstinence; after three repeats of this cycle, there was a 5-week abstinence period. Throughout the study, we examined body weight, food intake, locomotor activity, and anxiety- and depressive-like behaviors. During the treatment phase, HD MP decreased body weight, food intake, and depressive- and anxiety-like behaviors, while it increased locomotor activity. During intermittent abstinence, the effects of MP on locomotor activity were eliminated. During prolonged abstinence, most of the effects of HD MP were ameliorated to control levels, with the exception of weight loss and anxiolytic effects. These findings suggest that intermittent exposure to chronic MP causes physiological and behavioral effects that are mostly reversible following prolonged abstinence.

The Diagnosis and Treatment of Craniopharyngioma

Craniopharyngioma (CP) is a rare embryonic malformation of the sellar/parasellar region with a low histological grade. Clinical manifestations are related to hypothalamic/pituitary deficiencies, visual impairment, and increased intracranial pressure. Recent insight into the molecular pathogenesis of CP opens new perspectives on targeted therapy in papillary CP harboring BRAF-V600E mutations. Further research to elucidate pathogenic mechanisms and hopefully prevent hypothalamic involvement of CP is warranted. If the tumor is favorably localized, the therapy of choice is complete resection, with care taken to preserve the optical and hypothalamic functions. In patients with unfavorable tumor localization (i.e., hypothalamic involvement), the recommended therapy is a limited hypothalamus-sparing surgical strategy followed by local irradiation. Surgical treatment strategies should be based on a multidisciplinary approach involving experienced teams. Centralizing the treatment of CP in experienced "centers of excellence" and multicenter-based networks for reference assessments should be considered to assure a high standard of treatment quality. CP recurrence and progression are frequent. Irradiation has proven effective in reducing recurrences and progression. Proton beam therapy, available in a wider range in the near future, will help to avoid radio-oncological side effects. Anatomical involvement and/or surgical lesions of posterior hypothalamic areas can result in serious sequelae that compromise quality of life (QoL), such as hypothalamic obesity and psychopathological symptoms. Novel insights into neuropsychological sequelae after CP occurrence should be the basis for the development of therapeutic neuropsychological interventions. CP should be managed as a frequently chronic disease, providing ongoing care of pediatric and adult patients' clinical and QoL consequences by experienced multidisciplinary teams.

Diagnosis, Background, and Treatment of Hypothalamic Damage in Craniopharyngioma

Craniopharyngiomas (CP) are rare brain tumors managed primarily with surgery and radiotherapy. There are 2 phenotypes of CP, i.e., one with a rather good outcome without hypothalamic damage and another with hypothalamic damage. With hypothalamic damage, progressive disease with recurrent operations and additional cranial radiotherapy often result in hypothalamic obesity, an affected psychosocial life, and cognitive dysfunction. The morbidity and mortality are increased for particularly cerebrovascular diseases. Preoperative hypothalamic involvement to predict hypothalamic damage is important for decision making for hypothalamus-sparing surgery. Also a postoperative hypothalamic damage evaluation with the use of hypothalamus volume measurement can predict hypothalamic obesity, which is important for early treatment options. The morbidity of CP includes cognitive dysfunction with attention deficits and impaired episodic memory and processing speed. Again patients with hypothalamic damage are more affected. Treatment options of hypothalamic obesity in the chronic phase are scarce and not convincingly successful. The most optimal situation is to try to hinder or stop the evolution of hypothalamic obesity. Prevention of hypothalamic damage is recommended, with special regard to hypothalamus-sparing therapeutic approaches that respect the integrity of essential nuclei located in both the medial and the posterior hypothalamic areas.

Craniopharyngioma

Craniopharyngiomas are rare malformational tumours of low histological malignancy arising along the craniopharyngeal duct. The two histological subtypes, adamantinomatous craniopharyngioma (ACP) and papillary craniopharyngioma (PCP), differ in genesis and age distribution. ACPs are diagnosed with a bimodal peak of incidence (5-15 years and 45-60 years), whereas PCPs are restricted to adults mainly in the fifth and sixth decades of life. ACPs are driven by somatic mutations in CTNNB1 (encoding β-catenin) that affect β-catenin stability and are predominantly cystic in appearance. PCPs frequently harbour somatic BRAFV600E mutations and are typically solid tumours. Clinical manifestations due to increased intracranial pressure, visual impairment and endocrine deficiencies should prompt imaging investigations, preferentially MRI. Treatment comprises neurosurgery and radiotherapy; intracystic chemotherapy is used in monocystic ACP. Although long-term survival is high, quality of life and neuropsychological function are frequently impaired due to the close anatomical proximity to the optic chiasm, hypothalamus and pituitary gland. Indeed, hypothalamic involvement and treatment-related hypothalamic lesions frequently result in hypothalamic obesity, physical fatigue and psychosocial deficits. Given the rarity of these tumours, efforts to optimize infrastructure and international collaboration should be research priorities.

Management of hypothalamic disease in patients with craniopharyngioma

Patients with craniopharyngioma experience excess morbidity and mortality when compared with the background population and with other hypopituitary patients. Large, suprasellar tumours which form micropapillae into surrounding structures can cause hypothalamic damage before any therapeutic intervention; attempted gross total resection can lead to hypothalamic obesity, sleep disorders, thirst disorders and dysregulation of temperature as well as panhypopituitarism. The management of tumour bulk and the pathophysiology of hypothalamic complications have been reviewed extensively. We present a practical, clinical approach to management of hypothalamic disease in a patient with craniopharyngioma and highlight potential targets for future pharmacological or surgical intervention.

Pharmacotherapy of obesity: Available medications and drugs under investigation

Obesity is a chronic disease with a continuously rising prevalence that currently affects more than half a billion people worldwide. Energy balance and appetite are highly regulated via central and peripheral mechanisms, and weight loss triggers a homeostatic response leading to weight regain. Lifestyle and behavioral modifications are the cornerstones of obesity management; however, they often fail to achieve or sustain long-term weight loss. Pharmacotherapy added onto lifestyle modifications results in an additional, albeit limited, weight reduction. Regardless, this weight reduction of 5-10% conveys multiple cardiovascular and metabolic benefits. In this review, evidence on the food and drug administration (FDA)-approved medications, i.e., orlistat, lorcaserin, phentermine/topiramate, liraglutide and naltrexone/bupropion, is summarized. Furthermore, anti-obesity agents in the pipeline for potential future therapeutic use are presented.

Pathophysiology and Individualized Treatment of Hypothalamic Obesity Following Craniopharyngioma and Other Suprasellar Tumors: A Systematic Review

The development of hypothalamic obesity (HO) following craniopharyngioma (CP) and other suprasellar tumors leads to reduced patient quality of life. No treatment algorithms are currently available for management of HO. Depending on which hypothalamic nuclei are destroyed, the pathophysiologic mechanisms and clinical symptoms that contribute to HO differ among patients. Herein, we review the contribution of the hypothalamus to the pathophysiologic mechanisms and symptoms underlying CP-associated HO. Additionally, we performed a systematic search of MEDLINE and Embase to identify all intervention studies for weight management in patients with CP or other suprasellar tumors published until September 2017. The search yielded 1866 publications, of which 40 were included. Of these 40 studies, we identified four modalities for intervention (i.e., lifestyle, dietary, pharmacotherapeutic, or surgical) within six clinical domains (i.e., psychosocial disorders, hyperphagia, sleep disturbances, decreased energy expenditure, hyperinsulinemia, and hypopituitarism). We used the findings from our systematic review, in addition to current knowledge on the pathophysiology of HO, to develop an evidence-based treatment algorithm for patients with HO caused by CP or other suprasellar tumors. Although the individual effects of the HO interventions were modest, beneficial individual effects may be achieved when the pathophysiologic background and correct clinical domain are considered. These two aspects can be combined in an individualized treatment algorithm with a stepwise approach for each clinical domain. Recently elucidated targets for HO intervention were also explored to improve future management of HO for patients with CP and other suprasellar tumors.

Treatment of Hypothalamic Obesity with Dextroamphetamine: A Case Series

BACKGROUND

A limited number of published case reports suggest a positive effect of dextroamphetamine, an adrenergic agonist affecting both the central nervous system (CNS) and peripheral nervous system, on physical activity and weight in patients with hypothalamic obesity (intractable obesity following CNS insult). Here, we present our clinical experience with dextroamphetamine treatment for hypothalamic obesity.

METHODS

The clinical course of all patients started on dextroamphetamine treatment for severe hypothalamic obesity at our institution between 2010 and 2013 is reported. Dextroamphetamine administration was initiated at a single dose of 5 mg per day and titrated to effect up to a dose of 20 mg/day. BMI z-score velocity was calculated as change in BMI z-score over standardized intervals of 12 months. Parameters of treatment success and adverse events were assessed in a standardized fashion.

RESULTS

Seven patients (2 males; mean age 17.6 years [range 12.9-24.5]) underwent individual treatment attempts with dextroamphetamine between 2010 and 2013. The primary diagnoses were craniopharyngioma (n = 4), ganglioglioma WHO I (n = 1), astrocytoma (n = 1), and neonatal meningitis (n = 1). Time from initial CNS insult to initiation of dextroamphetamine treatment averaged 5.2 years (range 2.4 months to 16.5 years). All patients demonstrated a steady increase in BMI z-score from the time of initial diagnosis until initiation of dextroamphetamine treatment. Mean baseline BMI z-score was +3.17 ± 0.93 (+1.9 to +4.4). Mean BMI z-score velocity decelerated to -0.18 ± 0.12 per year during the first year of treatment and stabilized at +0.05 ± 0.32 per year during the second year of treatment. No significant adverse events were reported.

CONCLUSION

Dextroamphetamine treatment led to stabilization or reduction of BMI z-score in a cohort of 7 patients with hypothalamic obesity, with no adverse effects. Considering the projected increase in BMI z-score according to the natural course of the disease, these findings are promising and warrant further study.

Hypothalamic Obesity: 4 Years of the International Registry of Hypothalamic Obesity Disorders

OBJECTIVE

Hypothalamic obesity (HyOb) is a rare cause of rapid weight gain and early metabolic comorbidities. Effective treatment strategies are limited. The registry collected participant data and compared treatment approaches.

METHODS

The International Registry of Hypothalamic Obesity Disorders (IRHOD) was created as a registry portal to provide education. Data collected from the initial 4 years were evaluated.

RESULTS

Eighty-seven participants were included for analysis (median age: 27 years, range: 3-71 years). A total of 96.5% had obesity, and 3.5% had overweight at maximal weight. Seventy-five had brain tumors (86%)-the majority were craniopharyngiomas (72% of those with tumors). Nontumor etiologies included congenital brain malformation (4.6%), traumatic brain injury (3.4%), and genetic anomaly (2.3%). Ninety percent received obesity treatments including nutritional counseling (82%), pharmacotherapy (59%), bariatric surgery (8%), and vagal nerve stimulation (1%). Forty-six percent reported follow-up BMI results after obesity treatment. Surgery was most effective (median BMI decrease: -8.2 kg/m2 , median interval: 2.6 years), with lifestyle intervention (BMI: -3.4 kg/m2 , interval: 1.2 years) and pharmacological therapy (BMI: -2.3 kg/m2 , interval: 0.8 years) being less effective. Eighty percent of participants reporting follow-up weight remained in the obesity range.

CONCLUSIONS

IRHOD identified a large cohort with self-reported HyOb. Surgical therapy was most effective at weight reduction. Nutritional counseling and pharmacotherapy modestly improved BMI. Stepwise treatment strategy for HyOb (including nutritional, pharmacological, and surgical therapies in an experienced center) may be most valuable.

Recovery from behavior and developmental effects of chronic oral methylphenidate following an abstinence period

Chronic oral methylphenidate (MP) exposure in rats is associated with numerous developmental and behavioral consequences. The present study investigated the persistence of the effects of chronic oral MP exposure after abstinence from MP use. Male and female rats were exposed to daily orally self-administered water, low dose MP (LD), or high dose (HD) MP for 13 weeks, followed by a 4-week abstinence period. Fluid, food consumption and bodyweights were monitored and animals were tested for locomotor activity, anxiety- and depressive-like symptoms, learning and memory, and social behavior during both the treatment and abstinence phases of the experiment. During treatment, MP attenuated bodyweight regardless of sex, but increased food and fluid consumption in females and males by 20.7% and 30.1%, respectively. MP also increased locomotor activity in both males and females observed as increased distance travelled in an open field. (59.1% and 95.9%, respectively) and increased locomotor activity in the home cage over a 24-hour circadian cycle (45.5% and 63.0%). Additionally, MP exerted an anxiolytic effect observed as increased time spent in the open arms of an elevated plus maze (31.1% in HD males, 59.2% in HD females), and an increased latency to immobility in a forced swim test (330% in HD males, 418% in HD females). The effects of MP (bodyweight, consumption, locomotion, anxiolytic, and anti-depressive) were, almost without exception, eliminated during the abstinence period. MP had no impact on learning and memory performance as measured by a T-maze, or social behavior during treatment. These findings suggest that the behavioral consequences of chronic oral MP treatment in our preclinical model are reversible in rats following an abstinence period from use of the drug.

Interventions for the Treatment of Craniopharyngioma-Related Hypothalamic Obesity: A Systematic Review

OBJECTIVE

Craniopharyngiomas (CPs) and their treatment are associated with hypothalamic damage that causes hypothalamic obesity (HO) in 30%-70% of cases. Thus, there is ongoing research regarding tangible solutions for HO, because these patients have unrelenting resistance to basic weight-loss interventions. This review aims to summarize the interventions that are used to treat CP-related HO (CP-HO), including pharmacotherapy and bariatric surgery.

METHODS

The Cochrane Library, EMBASE, and PubMed databases were searched up to June 2017 for relevant reports. Two reviewers conducted independent evaluations of the studies identified.

RESULTS

Eighteen articles were included in the systematic review, with 3 reports describing pharmacotherapy in randomized controlled trials and 15 reports describing bariatric surgery. Although several studies described effective interventions for treating CP-HO, the evidence base was limited by its low quality and our inability to perform a meta-analysis, which was related to a lack of adequate or integrated data.

CONCLUSIONS

Octreotide appears to be a preferred treatment for patients with CP-HO, based on limited data. Gastric bypass surgery may also be suitable for select patients with CP-HO, based on a review of various procedures in this setting. Microsurgical preservation of the hypothalamic structures is mandatory to decrease CP-HO-related morbidity and mortality. Further studies with adequate analytical power and sufficient follow-up are needed to identify effective strategies for CP-HO treatment.

New outlook on the diagnosis, treatment and follow-up of childhood-onset craniopharyngioma

Childhood-onset craniopharyngiomas are rare embryonic tumours of low-grade histological malignancy. Novel insights into the molecular pathogenesis of human adamantinomatous craniopharyngioma have started to unveil the possibility of testing novel treatments targeting pathogenic pathways. Hypothalamic involvement and/or treatment-related lesions result in impaired physical and social functionality and in severe neuroendocrine sequelae. Quality of survival in patients with craniopharyngioma with hypothalamic involvement is impaired by severe obesity, physical fatigue and non-optimal psychosocial development. Patients with craniopharyngioma involving hypothalamic structures have reduced 20-year overall survival, but overall and progression-free survival are not related to the degree of surgical resection. Irradiation is effective in the prevention of tumour progression and recurrence. For favourably localized craniopharyngiomas, the preferred treatment of choice is to attempt complete resection with preservation of visual, hypothalamic and pituitary function. For unfavourably localized tumours in close proximity to optic and/or hypothalamic structures, a radical neurosurgical strategy attempting complete resection is not recommended owing to potential severe sequelae. As expertise has been shown to have an impact on post-treatment morbidity, medical societies should establish criteria for adequate professional expertise for the treatment of craniopharyngioma. On the basis of these criteria, health authorities should organize the certification of centres of excellence that are authorized to treat and care for patients with this chronic disease.

Risk-adapted, long-term management in childhood-onset craniopharyngioma

PURPOSE

This report is a review of findings on the diagnosis, treatment, clinical course, follow-up, and prognosis of craniopharyngioma patients with special regard to clinical trials and long-term management.

METHODS

Literature search on Pubmed for paper published after 1994.

RESULTS

Craniopharyngiomas are rare, embryonic malformations of the sellar/parasellar region with low histological grade. Clinical manifestations are related to increased intracranial pressure, visual impairment, and hypothalamic/pituitary deficiencies. If the tumor is favorably localized, therapy of choice is complete resection, with care taken to preserve hypothalamic and optic functions. In patients with unfavorable tumor location (i.e. involvement of hypothalamic areas), recommended therapy is limited hypothalamus-sparing surgical strategy followed by irradiation. Irradiation has proven effective in treatment of recurrences and progression. Surgical lesions and/or anatomical involvement of posterior hypothalamic areas can result in serious sequelae, mainly hypothalamic syndrome.

CONCLUSIONS

It is crucial that craniopharyngioma be managed as a frequently chronic disease, providing ongoing care of pediatric and adult patients' by experienced multidisciplinary teams in the context of multicenter trials.

Robust Reductions of Excess Weight and Hyperphagia by Beloranib in Rat Models of Genetic and Hypothalamic Obesity

Hypothalamic lesions or deficient melanocortin (MC) signaling via MC4 receptor (MC4r) mutations often lead to hyperphagia and severe treatment-resistant obesity. We tested the methionine aminopeptidase 2-inhibitor beloranib (ZGN-440) in 2 male rat models of obesity, one modeling hypothalamic obesity with a combined medial hypothalamic lesion (CMHL) and the other modeling a monogenic form of obesity with MC4r mutations (MC4r knockout [MC4rKO]). In CMHL rats (age 3 months), postsurgery excess weight gain was significantly inhibited (ZGN-440, 0.2 ± 0.7 g/d; vehicle, 3.8 ± 0.6 g/d; P < 0.001) during 12 days of ZGN-440 treatment (0.1 mg/kg daily subcutaneously) together with a 30% reduction of daily food intake vs vehicle injection. In addition, ZGN-440 treatment improved glucose tolerance and reduced plasma insulin, and circulating levels of α-melanocyte stimulating hormone were increased. Serum lipid levels did not differ significantly in ZGN-440-treated vs vehicle-treated rats. Similar results were found in MC4rKO rats: ZGN-440 treatment (14-21 d) was associated with significant reductions of body weight gain (MC4rKO, -1.7 ± 0.6 vs 2.8 ± 0.4 g/d; lean wild-type controls, -0.7 ± 0.2 vs 1.7 ± 0.7 g/d; ZGN-440 vs vehicle, respectively), reduction of food intake (MC4rKO, -28%; lean controls, -7.5%), and insulin resistance, whereas circulating levels of interleukin-1β did not change. In both obesity models, body temperature and locomotor activity were not affected by ZGN-440 treatment. In conclusion, the robust reduction of body weight in response to ZGN-440 observed in rats with severe obesity is related to a strong reduction of food intake that is likely related to changes in the central regulation of feeding.

Interventions for managing weight change following paediatric acquired brain injury: a systematic review

OBJECTIVE

To systematically review literature reporting interventions for weight change following paediatric acquired brain injury (ABI).

METHOD

A systematic search of the literature was conducted using advanced search techniques. The retrieval identified 1562 papers, of which 30 were relevant. The total number of paediatric participants was 759.

RESULTS

There is a paucity of higher quality evidence to support the use of weight change interventions following paediatric ABI. Substantial variation in screening, outcome measures, intervention, and reporting were demonstrated. Some support was found for the use of hypothalamic-sparing surgery as a method to prevent obesity following craniopharyngioma resection.

INTERPRETATION

There is a need for further study in this area to inform clinical and research practice; recommendations are given.

Update on childhood craniopharyngiomas

PURPOSE OF REVIEW

Craniopharyngioma location impacts treatment approach. Imaging advances allow for better anatomical localization, which can help determine the best surgical plan. Recent discoveries have also led to a better understanding of craniopharyngioma development and potential treatments. This review includes publications January 2015 through March 2016 and prior key reports.

RECENT FINDINGS

Recent findings confirm that third ventricular and hypothalamic involvement are associated with highest risk of hypothalamic dysfunction after surgery. Both presentation and MRI can aid in presurgical grading to try to limit development of hypothalamic obesity, somnolence, neurocognitive dysfunction, decreased quality of life, and other morbidities. Targeted therapies may also prove useful in avoiding treatment complications. In total, 14-50% of adult-onset craniopharyngioma are papillary; the majority with a mutation in exon 3 of BRAF and may respond to BRAF inhibitors and mitogen-activated protein kinase inhibitors. The remaining adult-onset and majority of childhood-onset are adamantinomatous; often with mutations in CTNNB1, which encodes β-catenin, leading to overactivation of the WNT signaling pathway.

SUMMARY

Significant morbidities are associated with craniopharyngioma. Targeted medical therapies are on the horizon. Until that time, the surgical approach and decision for radiation therapy should be chosen to limit long-term sequelae.

Late endocrine effects of childhood cancer

The cure rate for paediatric malignancies is increasing, and most patients who have cancer during childhood survive and enter adulthood. Surveillance for late endocrine effects after childhood cancer is required to ensure early diagnosis and treatment and to optimize physical, cognitive and psychosocial health. The degree of risk of endocrine deficiency is related to the child's sex and their age at the time the tumour is diagnosed, as well as to tumour location and characteristics and the therapies used (surgery, chemotherapy or radiation therapy). Potential endocrine problems can include growth hormone deficiency, hypothyroidism (primary or central), adrenocorticotropin deficiency, hyperprolactinaemia, precocious puberty, hypogonadism (primary or central), altered fertility and/or sexual function, low BMD, the metabolic syndrome and hypothalamic obesity. Optimal endocrine care for survivors of childhood cancer should be delivered in a multidisciplinary setting, providing continuity from acute cancer treatment to long-term follow-up of late endocrine effects throughout the lifespan. Endocrine therapies are important to improve long-term quality of life for survivors of childhood cancer.

Craniopharyngioma and hypothalamic injury: latest insights into consequent eating disorders and obesity

PURPOSE OF REVIEW

Hypothalamic alterations, pathological or treatment induced, have major impact on prognosis in craniopharyngioma patients mainly because of consequent hypothalamic obesity. Recent insight in molecular genetics, treatment strategies, risk factors and outcomes associated with hypothalamic obesity provide novel therapeutic perspectives. This review includes relevant publications since 2013.

RECENT FINDINGS

Recent findings confirm that alterations in posterior hypothalamic areas because of tumour location and/or treatment-related injuries are associated with severe hypothalamic obesity, reduced overall survival and impaired quality of life in long-term survivors of childhood-onset craniopharyngioma. However, eating disorders are observed because of hypothalamic obesity without clear disease-specific patterns. Treatment options for hypothalamic obesity are very limited. Treatment with invasive, nonreversible bariatric methods such as Roux-en-Y gastric bypass is most efficient in weight reduction, but controversial in the paediatric population because of medical, ethical, and legal considerations. Accordingly, treatment in craniopharyngioma should focus on prevention of (further) hypothalamic injury. Presurgical imaging for grading of hypothalamic involvement should be the basis for hypothalamus-sparing strategies conducted by experienced multidisciplinary teams.

SUMMARY

Until a nonsurgical therapeutic option for hypothalamic obesity for paediatric patients is found, prevention of hypothalamic injury should be the preferred treatment strategy, conducted exclusively by experienced multidisciplinary teams.

Activation of nuclear factor kappa B pathway and reduction of hypothalamic oxytocin following hypothalamic lesions

Background

Hypothalamic obesity (HO) occurs in patients with tumors and lesions in the medial hypothalamic region. In this study, a hyperphagic rat model of combined medial hypothalamic lesions (CMHL) was used to test which specific inflammatory molecules are involved.

Methods

In order to target specific homeostatic medial hypothalamic nuclei (arcuate, ventromedial, and dorsomedial nuclei), male Sprague-Dawley rats (age of 8 weeks, ~250 g body weight) received four electrolytic lesions or sham surgery. Post-surgery food intake and weight changes were tracked and hypothalamic gene expression for inflammatory molecules as well as anorexigenic peptide oxytocin 7 days and 7 months post-surgery were tested.

Results

Seven days post-surgery, average food intake increased by 23%, and body weight gain had increased by 68%. Toll-like 4 receptor/nuclear factor–κB (TLR4/NF–κB)—pathway was specifically activated in the mediobasal hypothalamus (MBH), resulting in 3-fold higher tumor necrosis factor (TNF)-α, 10-fold higher interleukin (IL) 1-β mRNA levels, and higher expression of suppression of cytokine signaling (SOCS) 3, while oxytocin mRNA levels were significantly reduced in CMHL rats versus sham surgery rats 7 days post-surgery. At 7 months, inflammation was less stimulated in MBH of CMHL rats compared to 7 days post-surgery and SOCS 3 as well as oxytocin mRNA levels were comparable between the two groups.

Conclusion

Medial hypothalamic lesions are associated with strong post-surgery hyperphagia and activation of TLR4/NF–κB—pathway as well as reduced expression of oxytocin in the hypothalamus.

Hypothalamic Obesity in Craniopharyngioma Patients: Disturbed Energy Homeostasis Related to Extent of Hypothalamic Damage and Its Implication for Obesity Intervention

Hypothalamic obesity (HO) occurs in patients with tumors and lesions in the medial hypothalamic region. Hypothalamic dysfunction can lead to hyperinsulinemia and leptin resistance. This review is focused on HO caused by craniopharyngiomas (CP), which are the most common childhood brain tumors of nonglial origin. Despite excellent overall survival rates, CP patients have substantially reduced quality of life because of significant long-term sequelae, notably severe obesity in about 50% of patients, leading to a high rate of cardiovascular mortality. Recent studies reported that both hyperphagia and decreased energy expenditure can contribute to severe obesity in HO patients. Recognized risk factors for severe obesity include large hypothalamic tumors or lesions affecting several medial and posterior hypothalamic nuclei that impact satiety signaling pathways. Structural damage in these nuclei often lead to hyperphagia, rapid weight gain, central insulin and leptin resistance, decreased sympathetic activity, low energy expenditure, and increased energy storage in adipose tissue. To date, most efforts to treat HO have shown disappointing long-term success rates. However, treatments based on the distinct pathophysiology of disturbed energy homeostasis related to CP may offer options for successful interventions in the future.

Neuroendocrine Disorders in Pediatric Craniopharyngioma Patients

Childhood-onset craniopharyngiomas are partly cystic embryonic malformations of the sellar/parasellar region. The therapy of choice in patients with favorable tumor localization is complete resection with a specific focus on maintaining optical and hypothalamic neuroendocrine functions. In patients with unfavorable tumor localization (i.e., hypothalamic involvement), a limited hypothalamus-sparing surgical strategy followed by local irradiation is recommended. Involvement and/or surgical lesions of posterior hypothalamic areas cause major neuroendocrine sequelae. The overall survival rates are high (92%) but neuroendocrine disorders such as obesity and metabolic syndrome due to involvement and/or treatment-related hypothalamic lesions have major negative impact on survival and quality of life. Recurrences and progressions are frequent post-surgical events. Because irradiation is efficient in preventing tumor progression, appropriate timing of post-surgical irradiation is currently under investigation in a randomized multinational trial (KRANIOPHARYNGEOM 2007). Childhood-onset craniopharyngioma should be recognized as a chronic disease requiring treatment and constant monitoring of the clinical and quality of life consequences, frequently impaired due to neuroendocrine disorders, by experienced multidisciplinary teams in order to provide optimal care of surviving patients.

Craniopharyngioma

This report is a review of findings on the diagnosis, treatment, clinical course, and prognosis of craniopharyngioma patients. Craniopharyngiomas are rare, partly cystic and calcified embryonic malformations of the sellar/parasellar region with low histological grade (WHO I°). A bimodal age distribution has been shown, with peak incidence rates in childhood-onset at 5-14 years and adult-onset craniopharyngioma at 50-74 years. Clinical manifestations are related to hypothalamic/pituitary deficiencies, visual impairment, and increased intracranial pressure. If the tumor is favorably localized, the therapy of choice is complete resection, with care taken to preserve optical and hypothalamic functions. In patients with unfavorable tumor localization (i.e., hypothalamic involvement), recommended therapy is a limited hypothalamus-sparing surgical strategy followed by local irradiation. Although overall survival rates are high (92%), recurrences and progressions are frequent. Irradiation has proven effective in reducing recurrences and progression, and timing of postsurgical irradiation in childhood-onset cases is currently under investigation in a randomized multinational trial (KRANIOPHARYNGEOM 2007). Anatomical involvement and/or surgical lesions of posterior hypothalamic areas can result in serious quality of life-compromising sequelae such as hypothalamic obesity, psychopathological symptoms, and/or cognitive problems. It is crucial that craniopharyngioma be managed as a frequently chronic disease, providing ongoing care of pediatric and adult patients' clinical and quality of life consequences by experienced multidisciplinary teams.