Re: Mangosteen and Its Bioactive Compounds Show Potential Beneficial Impacts for Those with Metabolic Syndrome

Date: 02-15-2018 HC# 091761-586 Tousian Shandiz H, Razavi BM, Hosseinzadeh H. Review of Garcinia mangostana and its xanthones in metabolic syndrome and related complications. Phytother Res. August 2017;31(8):1173-1182. Metabolic syndrome is a composite of metabolic disorders leading to elevated risk for diabetes and other chronic health problems. The five conditions potentially comprising metabolic syndrome are abdominal obesity, dyslipidemia, low concentration of high-density lipoprotein (HDL) cholesterol, elevated blood pressure, and elevated fasting blood glucose. Those who have three or more of these criteria are considered to have metabolic syndrome. As this condition involves multiple systems in the body, botanicals with bioactive compounds of multifaceted activity may be useful in alleviating metabolic syndrome. Mangosteen (Garcinia mangostana, Clusiaceae) has a history of traditional medicinal use. It has been found to have anti-inflammatory and antioxidant activity, as well as hypoglycemic and anti-obesity properties, all pertinent to metabolic syndrome. This review summarizes the current state of mangosteen and its potential in alleviating metabolic syndrome. The databases PubMed, SCOPUS, and Web of Science were searched with terms including "mangosteen," "antidiabetic," and "hyperlipidemia," among others. In total, 581 articles resulted from the search, and 60 were summarized for this review. One compound found in mangosteen, α-mangostin, was found to attenuate fatty acid synthase and glucose uptake in pre-adipocyte cells, as well as to downregulate the expression of peroxisome proliferator-activated receptor gamma (PPARγ, a metabolic regulator). In a mouse study, this compound alone and in peel extract was shown to lower fat accrual, glucose concentrations, and lipids such as total cholesterol, low-density lipoprotein (LDL) cholesterol, and free fatty acids. It also reduced HDL cholesterol. In a rat study, the ethanol extract of mangosteen had a positive impact on lipid profile and decreased hydrogen peroxide concentrations. Mangosteen given to rats on a cholesterol diet hindered both an increase in lipids and a lowering of antioxidant activity in plasma. When investigated for anti-inflammatory activity, one compound found in mangosteen, γ-mangostin, was reported to decrease activity of nuclear factor-kappa B (NF-κB, an inflammation regulator) in inflammatory macrophages and adipocyte cells; this compound also alleviated insulin resistance in adipocytes. In another cell model of inflammation, multiple mangosteen compounds were found to dampen the activity of several inflammation markers, such as inducible nitric oxide synthase (iNOS), tumor necrosis factor-alpha (TNF-α), and interleukin-4 (IL-4). In a clinical trial in a healthy population, 30 days of mangosteen consumption increased blood antioxidant activity and decreased C-reactive protein, a marker of inflammation. Both body mass index and C-reactive protein were decreased in overweight and obese patients consuming mangosteen juice for eight weeks. In rats consuming the ethanol extract of mangosteen pericarp, concentrations of lipids such as LDL cholesterol, total cholesterol, and triglycerides were decreased. HDL also was decreased. It is also stated that this extract showed hypoglycemic activity. Also, in male rats, the compound α-mangostin decreased the animals' hemoglobin A1c, insulin, total cholesterol and triglyceride concentrations, TNF-α, and advanced glycation end products (AGEs, indicators of elevated reactive oxygen species); this compound was also shown in this study to improve the blood-retinal barrier in eyes. When this compound was fed to a rat model of type 1 diabetes, beneficial effects on the male reproductive system were observed, such as improved sperm density. In summary, there is evidence in the literature that mangosteen and its bioactive compounds have potential beneficial impacts on those with metabolic syndrome through lipid-lowering, hypoglycemic, and/or anti-inflammation effects. As this review primarily focused on in vitro and in vivo studies, clinical trials addressing safety and efficacy in those with metabolic syndrome are necessary. —Amy C. Keller, PhD