Pharmacogenetics of obesity drug therapy

Pharmacogenomics of Medication-Induced Weight Gain and Antiobesity Medications

Obesity is a chronic, multifactorial disease associated with a large number of comorbidities. The clinical management of obesity involves a stepwise integrated approach, beginning with behavioral and lifestyle modification, followed by antiobesity medications, endobariatric procedures, and bariatric surgery. Weight gain and subsequent obesity are common side effects of medications, such as prednisone or antipsychotics. In this era of precision medicine, it is essential to identify patients at the highest risk of weight gain as a result of medication use. Pharmacogenomics could play an important role in obesity management by optimizing use of antiobesity medications as well as minimizing adverse weight gain. This review aims to provide a comprehensive analysis of the current literature on the role of pharmacogenomics in obesity and medication-induced weight gain. In summary, there are more robust studies of medication associated with weight gain and pharmacogenomics, and more studies are needed to understand the role of pharmacogenomics in antiobesity medications.

Anti-obesity effect of garlic oil on obese rats via Shenque point administration

ETHNOPHARMACOLOGICAL RELEVANCE

Shenque is an acupoint located in the umbilicus and connected with the meridians. Thus, acupoint herbs applied at Shenque plays a pivotal role in the Chinese traditional medicine due to its sensitivity, permeability, and absorption. Many studies reported the use of Shenque point as a successful therapeutic approach. However, the effect of garlic oil (GO) applied at Shenque point to combat obesity is unmet. Consequently, we investigated the potential benefit of GO applied at Shenque point against obesity.

AIM OF THE STUDY

To investigate GO effects on obese rats applied at Shenque acupoint and orally administered, and to identify the chemical constituents of GO.

MATERIALS AND METHODS

Rats were randomly divided into 2 groups: naive and model group. The model group rats were fed with a high fat diet for 7 weeks to induce obesity, and then they were randomly divided into 5 groups: model, GO Shenque point treated groups (25, 50 and 100 mg/kg/day) and oral group (50 mg/kg/day). Biochemical indexes in the serum, weight of adipose tissue and liver histopathology were evaluated after 6 weeks of GO treatment using a Hitachi 7080 analyzer (Hitachi, Japan). Moreover, GO chemical components were detected by gas chromatography-mass spectrometer (GC-MS).

RESULTS

Compared with the naive rats, model rats exhibited higher body and liver weight, increased fat deposition, higher triglyceride concentration and alveolar development. In contrast, GO Shenque point treated groups showed a substantial decrease in body weight (P = 0.358, 0.028, 0.031, respectively), fat mass, cholesterol (P = 0.004, 0.041, 0.001, respectively), triglyceride (P = 0.001, 0.001, 0.001, respectively), and low density lipoprotein concentrations (P = 0.001, 0.000, 0.001, respectively). The effect was more remarkable than the GO orally administered. In addition, twelve GO organosulfur compounds were identified by GC-MS and diallyl trisulfide (DATS) was detected as the main compound, with a 32.08% concentration.

CONCLUSIONS

These findings demonstrated that GO had a significant anti-obesity effect on obese rats by reducing the body weight and protecting the liver from damage, and the effect of Shenque point treatment was better than oral administration, suggesting that GO was an effective weight-loss drug and Shenque point administration might be considered as a new anti-obesity approach.

Intraventricular administration of Tenebrio molitor larvae extract regulates food intake and body weight in mice with high-fat diet-induced obesity

We recently reported the in vitro and in vivo antiobesity effects of Tenebrio molitor larvae, a traditional food in many countries, but it remains unknown how the larvae affect appetite regulation in mice with diet-induced obesity. We hypothesized that the extract of T molitor larvae mediates appetite by regulating neuropeptide expression. We investigated T molitor larvae extract's (TME's) effects on anorexigenesis and endoplasmic reticulum (ER) stress-induced orexigenic neuropeptide expression in the hypothalami of obese mice. Intracerebroventricular TME administration suppressed feeding by down-regulating the expression of the orexigenic neuropeptides neuropeptide Y and agouti-related protein. T molitor larvae extract significantly reduced the expression of ER stress response genes. These results suggest that TME and its bioactive components are potential therapeutics for obesity and ER stress-driven disease states.

From Genome-Wide Association Study to Phenome-Wide Association Study: New Paradigms in Obesity Research

Obesity is a condition in which excess body fat has accumulated over an extent that increases the risk of many chronic diseases. The current clinical classification of obesity is based on measurement of body mass index (BMI), waist-hip ratio, and body fat percentage. However, these measurements do not account for the wide individual variations in fat distribution, degree of fatness or health risks, and genetic variants identified in the genome-wide association studies (GWAS). In this review, we will address this important issue with the introduction of phenome, phenomics, and phenome-wide association study (PheWAS). We will discuss the new paradigm shift from GWAS to PheWAS in obesity research. In the era of precision medicine, phenomics and PheWAS provide the required approaches to better definition and classification of obesity according to the association of obese phenome with their unique molecular makeup, lifestyle, and environmental impact.

Allomyrina Dichotoma Larvae Regulate Food Intake and Body Weight in High Fat Diet-Induced Obese Mice Through mTOR and Mapk Signaling Pathways

Recent evidence has suggested that the Korean horn beetle (Allomyrina dichotoma) has anti-hepatofibrotic, anti-neoplastic, and antibiotic effects and is recognized as a traditional medicine. In our previous works, Allomyrina dichotoma larvae (ADL) inhibited differentiation of adipocytes both in vitro and in vivo. However, the anorexigenic and endoplasmic reticulum(ER) stress-reducing effects of ADL in obesity has not been examined. In this study, we investigated the anorexigenic and ER stress-reducing effects of ADL in the hypothalamus of diet-induced obese (DIO) mice. Intracerebroventricular (ICV) administration of ethanol extract of ADL (ADE) suggested that an antagonizing effect on ghrelin-induced feeding behavior through the mTOR and MAPK signaling pathways. Especially, ADE resulted in strong reduction of ER stress both in vitro and in vivo. These findings strongly suggest that ADE and its constituent bioactive compounds are available and valuable to use for treatment of various diseases driven by prolonged ER stress.

Co-activation of AKT and c-Met triggers rapid hepatocellular carcinoma development via the mTORC1/FASN pathway in mice

Activation of the AKT/mTOR cascade and overexpression of c-Met have been implicated in the development of human hepatocellular carcinoma (HCC). To elucidate the functional crosstalk between the two pathways, we generated a model characterized by the combined expression of activated AKT and c-Met in the mouse liver. Co-expression of AKT and c-Met triggered rapid liver tumor development and mice required to be euthanized within 8 weeks after hydrodynamic injection. At the molecular level, liver tumors induced by AKT/c-Met display activation of AKT/mTOR and Ras/MAPK cascades as well as increased lipogenesis and glycolysis. Since a remarkable lipogenic phenotype characterizes liver lesions from AKT/c-Met mice, we determined the requirement of lipogenesis in AKT/c-Met driven hepatocarcinogenesis using conditional Fatty Acid Synthase (FASN) knockout mice. Of note, hepatocarcinogenesis induced by AKT/c-Met was fully inhibited by FASN ablation. In human HCC samples, coordinated expression of FASN, activated AKT, and c-Met proteins was detected in a subgroup of biologically aggressive tumors. Altogether, our study demonstrates that co-activation of AKT and c-Met induces HCC development that depends on the mTORC1/FASN pathway. Suppression of mTORC1 and/or FASN might be highly detrimental for the growth of human HCC subsets characterized by concomitant induction of the AKT and c-Met cascades.