The effect of carbamazepine treatment on serum leptin levels

Obesity and metabolic syndrome in patients with epilepsy, their relation with epilepsy control

Obesity and metabolic syndrome (MetS) are commonly observed in patients with epilepsy (PWE). Obesity and MetS are not only affecting the physical fitness and quality of life of these patients, rather antiepileptic drugs (AEDs) compliance and seizure control have also been affected. The objective of this review is to search the published literature regarding the prevalence of obesity and MetS in PWE and their relation to the response to AEDs. A comprehensive search using PubMed, Cochrane Databases, and Google Scholar was performed. A supplementary citation search was also conducted by analyzing the reference lists of identified sources. The initial search revealed 364 articles of potential relevance. The studies were analyzed in detail to obtain clinical information relevant to the objectives of the review. Many observational, case control studies, randomized control trials and few review articles were included for critical appraisal and review writing. Epilepsy is associated with MetS and obesity in all age groups. AEDs and lack of exercise are the chief causes while metabolic disturbances such as adiponectin, mitochondrial dysfunction, valproic acid (VPA)-associated insulin resistance, leptin deficiency, and endocrine dysfunction are also addressable factors. Although the risk of drug-resistant epilepsy (DRE) is also higher among obese PWE, the interaction between, MetS, and its components with DRE remain to be fully investigated. Further research is required to elucidate their interplay. Appropriate and careful selection of AEDs without compromising therapeutic efficacy supplemented by lifestyle counseling for exercise and diet should be practiced to avoid weight gain and potential DRE.

Metabolic syndrome and obstructive sleep apnea syndrome among patients with epilepsy on monotherapy

OBJECTIVES

The study aimed to determine the frequency of metabolic syndrome (MetS) and obstructive sleep apnea syndrome (OSAS) in patients with epilepsy receiving monotherapy and the relationship between these syndromes and antiepileptic drugs (AEDs).

METHODS

Two hundred and ninety-seven patients with epilepsy between the ages of 18-65 years receiving monotherapy for at least one year and 50 healthy participants were enrolled. Body mass indices and waist circumferences were measured. Serum fasting glucose levels, high-density lipoprotein (HDL), low density lipoprotein (LDL), total cholesterol (TC), triglyceride, and serum AED concentrations were noted. The frequency of MetS in patients with epilepsy was calculated. The snoring, tiredness, observed apnea, high blood pressure, body mass index, age, neck circumference, and male gender (STOP-Bang) questionnaire was used to determine the risk of OSAS. The relationship between these two syndromes and seizure type, disease duration, AED dosage, and treatment duration was analyzed.

RESULTS

Metabolic syndrome was more frequent in patients with epilepsy compared with healthy participants (32.6% vs. 12.0%), and it was diagnosed in 37.8% of patients receiving valproic acid (VPA), 36.1% of patients receiving carbamazepine (CBZ), 34.9% of patients receiving oxcarbazepine (OXC), and 30.5% of patients on levetiracetam (LEV). There was a positive correlation between VPA treatment duration and MetS existence (p < 0.05). However, MetS frequency did not change because of seizure type, disease duration, or AED dosages in patients with epilepsy receiving monotherapy. The risk for OSAS was higher in patients with epilepsy compared with healthy participants (24.6% vs. 12%), and it was calculated high in 27.7% of patients receiving CBZ, 32.2% of patients receiving LEV, and 30.2% of patients receiving OXC. The OSAS risk was higher in patients who have focal seizures than generalized seizures (p = 0.044). There was no relationship between OSAS risk and duration of epilepsy, duration of treatment, drug doses, and serum drug levels (p > 0.05).

CONCLUSION

Higher frequency of MetS and OSAS risk should be kept in mind on clinical follow-up of patients with epilepsy receiving monotherapy.

Carbamazepine Enhances Adipogenesis by Inhibiting Wnt/β-catenin Expression

Carbamazepine is a drug that is widely used in the treatment of epilepsy and bipolar disorder. The prevalence of obesity in patients treated with carbamazepine has been frequently reported. However, whether carbamazepine affects adipogenesis, one of the critical steps in the development of obesity, remains unclear. Here, we show that carbamazepine increased the expression levels of peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein β (C/EBPβ), and fatty acid synthase (FASN) in 3T3-L1 cells. Notably, carbamazepine inhibited the expression levels of β-catenin, a negative regulator of adipogenesis, leading to enhanced adipogenesis. Conversely, β-catenin overexpression abolished the effect of carbamazepine on adipogenic gene expression. However, depletion of β-catenin further enhanced PPARγ expression. In addition, carbamazepine reduced β-catenin expression by lowering the levels of phospho-low density lipoprotein receptor-related protein 6 (p-LRP6) and phospho-glycogen synthase kinase 3β (p-GSK3β) in Wnt/β-catenin signaling. Moreover, carbamazepine reduced Wnt mRNA expression and decreased the promoter activities of TCF, the target of β-catenin during adipogenesis. These results suggest that carbamazepine enhances adipogenesis by suppressing Wnt/β-catenin expression, indicating its potential effects on obesity-related metabolism.

Comparison of body composition in persons with epilepsy on conventional & new antiepileptic drugs

BACKGROUND & OBJECTIVES

Certain antiepileptic drugs (AEDs) such as valproic acid (VPA) are known to affect body weight, and lipid profile. However, evidences regarding effects of AEDs on the body composition are deficient. This cross-sectional study compared the body composition and lipid profile among patients with epilepsy on newer and conventional AEDs.

METHODS

The patients with epilepsy (n=109) on treatment with conventional and newer AEDs (levetiracetam, lamotrigine and clobazam) for > 6 months were enrolled. Of these, 70 were on monotherapy: levetiracetam (n=12), VPA (n=16), carbamazepine (n=20) and phenytoin (n=22) and the remaining on polytherapy. Their body composition [body fat mass, lean dry mass (LDM), total body water (TBW), intracellular water (ICW), extracellular water (ECW) and basal metabolic rate (BMR) was estimated and biochemical parameters were assessed.

RESULTS

Levetiracetam group had no significant difference with VPA, carbamazepine, phenytoin and control groups, except low LDM (17.8±2.4) than VPA groups (20.2±2.7, p<0.05). In comparison with control, AEDs monotherapy groups had no significant difference, except higher LDM and ECW in VPA group. Among groups based on conventional and newer AEDs, there was no significant difference in body composition parameters except for higher LDM (as % of BW) in conventional AEDs only treated group than control (p<0.01).

INTERPRETATION & CONCLUSIONS

The alterations observed in body composition with valproic acid in contrast to other AEDs like levetiracetam, carbamazepine and phenytoin could affect treatment response in epilepsy especially in subjects with already altered body composition status like obese and thin frail patients, which needs to be established by prospective studies (CTRI/2013/05/003701).

Impact of epilepsy and antiepileptic medications on the metabolic profile in adults with autism spectrum disorder and intellectual disabilities

Epilepsy is common in individuals with autism spectrum disorder (ASD) and intellectual disabilities (ID). Antiepileptic medications, such as valproic acid (VPA), were associated with changes in BMI, metabolic syndrome, dyslipidemia, and hyperinsulinemia. This study aimed to investigate how epilepsy and antiepileptic treatments affect BMI, fasting blood glucose (FBG), and total cholesterol of individuals with ASD or ID. Data on epilepsy diagnoses, treatment with VPA, carbamazepine or other antiepileptics, BMI, FBG, and total cholesterol levels were obtained from the medical charts of 80 adults with ASD and 77 adults with ID and analyzed using appropriate statistical tools. Participants with epilepsy had lower BMI and FBG than participants without epilepsy (BMI: 23.18 ± 5.43 vs. 25.61 ± 5.74 kg/m2, respectively, F = 6.64, d.f. = 1.140; P = 0.011, FBG: 72.53 ± 11.26 vs. 79.98 ± 14.64 mg/dl, respectively, F = 10.46, d.f. = 1.135 P = 0.002). Those treated with VPA had lower total cholesterol levels compared with those untreated (156.56 ± 26.13 vs. 172.42 ± 33.82 mg/dl, respectively, F = 7.44, d.f. = 1.150; P = 0.007), but did not differ in BMI and FBG. Individuals with ASD or ID, and epilepsy were leaner and had lower FBG than those without epilepsy. In addition, total cholesterol levels were lower in VPA-treated participants than in untreated ones, but BMI and FBG levels were similar.

Carbamazepine directly inhibits adipocyte differentiation through activation of the ERK 1/2 pathway

BACKGROUND AND PURPOSE

Carbamazepine (CBZ), known for its anti-epileptic, analgesic and mood-stabilizing properties, is also known to induce weight gain but the pathophysiology of this adverse effect is still largely unknown. We tested the hypothesis that CBZ could have a direct effect on adipocyte development and metabolism. EXPERIMENTAL RESEARCH: We studied the effects of CBZ on morphological biochemical and molecular markers of adipogenesis, using several pre-adipocyte murine cell lines (3T3-L1, 3T3-F442A and T37i cells) and primary cultures of human pre-adipocytes. To delineate the mechanisms underlying the effect of CBZ, clonal expansion of pre-adipocytes, pro-adipogenic transcription factors, glucose uptake and lipolysis were also examined.

KEY RESULTS

CBZ strongly inhibited pre-adipocyte differentiation and triglyceride accumulation in a time- and dose-dependent manner in all models. Pleiotropic mechanisms were at the basis of the inhibitory effects of CBZ on adipogenesis and cell lipid accumulation. They included suppression of both clonal expansion and major adipogenic transcription factors such as PPAR-γ and CCAAT/enhancer binding protein-α, activation of basal lipolysis and decrease in insulin-stimulated glucose transport.

CONCLUSIONS AND IMPLICATIONS

The effect of CBZ on adipogenesis involves activation of the ERK1/2 pathway. Our results show that CBZ acts directly on pre-adipocytes and adipocytes to alter adipose tissue development and metabolism.

The long-term safety of antiepileptic drugs

Antiepileptic drugs (AEDs) are used by millions of people worldwide for the treatment of epilepsy, as well as in many other neurological and psychiatric conditions. They are frequently associated with adverse effects (AEs), which have an impact on the tolerability and success of treatment. Half the people who develop intolerable AEs discontinue treatment early on after initiation, while the majority of people will continue to be exposed to their effects for long periods of time. The long-term safety of AEDs reflects their potential for chronic, cumulative dose effects; rare, but potentially serious late idiosyncratic effects; late, dose-related effects; and delayed, teratogenic or neurodevelopmental effects. These AEs can affect every body system and are usually insidious. With the exception of delayed effects, most other late or chronic AEs are reversible. To date, there is no clear evidence of a carcinogenic effect of AEDs in humans. While physicians are aware of the long-term AEs of old AEDs (the traditional liver enzyme-inducing AEDs and valproate), information about AEs of new AEDs (such as lamotrigine, levetiracetam, oxcarbazepine, topiramate or zonisamide), particularly of their teratogenic effects, has emerged over the years. Sporadic publications have raised issues about AEs of the newer AEDs eslicarbazepine, retigabine, rufinamide, lacosamide and perampanel but their long-term safety profiles may take years to be fully appreciated. Physicians should not only be aware of the late and chronic AEs of AEDs but should systematically enquire and screen for these according to the individual AED AE profile. Care should be taken for individuals with comorbid conditions that may render them more susceptible to specific AEs. Prevention and appropriate management of long-term AED AEs is expected to improve adherence to treatment, quality of life and control of epilepsy.