Amyrins from Protium heptaphyllum Reduce High-Fat Diet-Induced Obesity in Mice via Modulation of Enzymatic, Hormonal And Inflammatory Responses.

Obesity remains a global problem. In search of phytochemicals that have antiobesity potential, this study evaluated α,ß-amyrin, a triterpenoid mixture from Protium heptaphyllum, on high-fat diet-induced obesity in mice. Groups of mice (n = 8) were fed a normal diet or a high-fat diet, and were orally treated or not treated with either α,ß-amyrin (10 or 20 mg/kg) or sibutramine (10 mg/kg) for 15 weeks. Variables measured at termination were body weight, visceral fat accumulation, adipocyte surface area, peroxisome proliferator-activated receptor gamma, and lipoprotein lipase expressions in adipose tissue, the levels of plasma glucose and insulin, the satiety hormones ghrelin and leptin, the digestive enzymes amylase and lipase, and the inflammatory mediators TNF-α, interleukin-6, and MCP-1. Results showed that α,ß-amyrin treatment resulted in lower high-fat diet-induced increases in body weight, visceral fat content, adipocyte surface area, peroxisome proliferator-activated receptor gamma, and lipoprotein lipase expressions, and blood glucose and insulin levels. Additionally, the markedly elevated leptin and decreased ghrelin levels seen in the high-fat diet-fed control mice were significantly modulated by α,ß-amyrin treatment. Furthermore, α,ß-amyrin decreased serum TNF-α and MCP-1. These results suggest that α,ß-amyrin could be beneficial in reducing high-fat diet-induced obesity and associated disorders via modulation of enzymatic, hormonal, and inflammatory responses.

The Resin from Protium heptaphyllum Prevents High-Fat Diet-Induced Obesity in Mice: Scientific Evidence and Potential Mechanisms.

Herbal compounds rich in triterpenes are well known to regulate glucose and lipid metabolism and to have beneficial effects on metabolic disorders. The present study investigated the antiobesity properties of resin from Protium heptaphyllum (RPH) and the possible mechanisms in mice fed a high-fat diet (HFD) for 15 weeks. Mice treated with RPH showed decreases in body weight, net energy intake, abdominal fat accumulation, plasma glucose, amylase, lipase, triglycerides, and total cholesterol relative to their respective controls, which were RPH unfed. Additionally, RPH treatment, while significantly elevating the plasma level of ghrelin hormone, decreased the levels of insulin, leptin, and resistin. Besides, HFD-induced increases in plasma levels of proinflammatory mediators TNF-α, IL-6, and MCP-1 were significantly lowered by RPH. Furthermore, in vitro studies revealed that RPH could significantly inhibit the lipid accumulation in 3T3-L1 adipocytes (measured by Oil-Red O staining) at concentrations up to 50 µg/mL. These findings suggest that the antiobese potential of RPH is largely due to its modulatory effects on various hormonal and enzymatic secretions related to fat and carbohydrate metabolism and to the regulation of obesity-associated inflammation.

1,8-cineole (eucalyptol) ameliorates cerulein-induced acute pancreatitis via modulation of cytokines, oxidative stress and NF-κB activity in mice.

AIMS: Acute pancreatitis (AP) is an inflammatory condition wherein pro-inflammatory mediators, oxidative stress, and NF-κB signaling play a key role. Currently, no specific therapy exists and treatment is mainly supportive and targeted to prevent local pancreatic injury and systemic inflammatory complications. This study was aimed to examine whether 1,8-cineole, a plant monoterpene with antioxidant and anti-inflammatory properties could ameliorate cerulein-induced acute pancreatitis. MAIN METHODS: AP was induced in Swiss mice by six one hourly injections of cerulein (50 µg/kg, i.p.). 1,8-cineole (100, 200 and 400mg/kg, p.o.) was administered 1h prior to first cerulein injection, keeping vehicle and thalidomide treated groups as controls. Blood samples were taken 6-h later to determine serum levels of amylase and lipase, and cytokines. The pancreas was removed for morphological examination, myeloperoxidase (MPO) and malondialdehyde (MDA) assays, reduced glutathione (GSH) levels, and for nuclear factor (NF)-κB immunostaining. KEY FINDINGS: 1,8-cineole effectively reduced the cerulein-induced histological damage, pancreatic edema and NF-κB expression, levels of MPO activity and MDA, and replenished the GSH depletion. Cerulein increased serum levels of amylase and lipase, and pro-inflammatory cytokines TNF-α, IL-1ß, and IL-6 were also decreased by 1,8-cineole pretreatment, similar to thalidomide, a TNF-α inhibitor. The anti-inflammatory IL-10 cytokine level was, however, enhanced by 1,8-cineole. SIGNIFICANCE: These findings indicate that 1,8-cineole can attenuate cerulein-induced AP via an anti-inflammatory mechanism and by combating oxidative stress. Further studies are needed to clearly elucidate its benefits in patients on acute pancreatitis.

Antihyperglycemic and hypolipidemic effects of α, ß-amyrin, a triterpenoid mixture from Protium heptaphyllum in mice.

BACKGROUND: Pentacyclic triterpenes in general exert beneficial effects in metabolic disorders. This study investigated the effects of α, ß-amyrin, a pentacyclic triterpene mixture from the resin of Protium heptaphyllum on blood sugar level and lipid profile in normal and streptozotocin (STZ)-induced diabetic mice, and in mice fed on a high-fat diet (HFD). FINDINGS: Mice treated with α, ß-amyrin (10, 30 and 100 mg/kg, p.o.) or glibenclamide (10 mg/kg, p.o.) had significantly reduced STZ-induced increases in blood glucose (BG), total cholesterol (TC) and serum triglycerides (TGs). Unlike glibenclamide that showed significant reductions in BG, TC and TGs in normoglycemic mice, α, ß-amyrin did not lower normal blood sugar levels but at 100 mg/kg, manifested a hypolipidemic effect. Also, α, ß-amyrin effectively reduced the elevated plasma glucose levels during the oral glucose tolerance test. Moreover, the plasma insulin level and histopathological analysis of pancreas revealed the beneficial effect of α, ß-amyrin in the preservation of beta cell integrity. In mice treated orally with α, ß-amyrin (10, 30 and 100 mg/kg) or fenofibrate (200 mg/kg), the HFD-associated rise in serum TC and TGs were significantly less. The hypocholesterolemic effect of α, ß-amyrin appeared more prominent at 100 mg/kg with significant decreases in VLDL and LDL cholesterol and an elevation of HDL cholesterol. Besides, the atherogenic index was significantly reduced by α, ß-amyrin. CONCLUSIONS: These findings reflect the potential antihyperglycemic and hypolipidemic effects of α, ß-amyrin mixture and suggest that it could be a lead compound for drug development effective in diabetes and atherosclerosis.

The natural flavonoid quercetin ameliorates cerulein-induced acute pancreatitis in mice.

Many plant-derived flavonoids including quercetin exhibit antioxidant and antiinflammatory properties. Proinflammatory cytokines and oxidative stress play an important role in acute pancreatitis. This study aimed to evaluate the effect of quercetin on cerulein-induced acute pancreatitis in mice. Animal groups were pretreated with quercetin (25, 50, 100 mg/kg, per os (p.o.)), thalidomide (200 mg/kg, p.o.) or vehicle (2% dimethyl sulfoxide (DMSO)) 1 h before hourly (x5) intraperitoneal injections of cerulein. A saline (0.9%, NaCl)-treated control group was included for comparison. Cerulein significantly enhanced the serum levels of amylase and lipase, and pancreatic myeloperoxidase activities, malondialdehyde and the proinflammatory cytokines tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and IL-6, as well as the pancreatic wet weight/body weight ratio. Cerulein significantly reduced the serum levels of IL-10. Histological assessment of the pancreas showed tissue edema, neutrophil infiltration, acinar vacuolization, and cell necrosis and a marked increase in the immunoreactivity staining for TNF-alpha. Pretreatment with quercetin or thalidomide significantly attenuated the severity of cerulein-induced acute pancreatitis as evidenced by effective reductions in the pancreatic wet weight/body weight ratio, biochemical indices, proinflammatory cytokines, myeloperoxidase activity, malondialdehyde formation, and an increase in antiinflammatory cytokine IL-10. Quercetin treatment also markedly suppressed the histological changes such as pancreatic edema, inflammatory cell infiltration, acinar cell necrosis, and the expression of TNF-alpha. Taken together, these results indicate that quercetin ameliorates the severity of cerulein-induced acute pancreatitis by acting as an antiinflammatory and antioxidant agent.