Impact of the lipase inhibitor orlistat on the human gut microbiota.

Orlistat, an anti-obesity agent, inhibits the metabolism and absorption of dietary fat by inactivating pancreatic lipase in the gut. The effect of orlistat on the gut microbiota of Japanese individuals with obesity is unknown. This study aimed to explore the effects of orlistat on the gut microbiota and fatty acid metabolism of Japanese individuals with obesity. Fourteen subjects with visceral fat obesity (waist circumference ≥85 cm) took orlistat orally at a dose of 60 mg, 3 times a day for 8 weeks. Body weight; waist circumference; visceral fat area; levels of short-chain fatty acids, gut microbiota, fatty acid metabolites in the feces, and gastrointestinal hormones; and adverse events were evaluated. Body weight, waist circumference, and blood leptin concentrations were significantly lower after orlistat treatment (mean ± standard deviation, 77.8 ± 9.1 kg; 91.9 ± 8.7 cm; and 4546 ± 3211 pg/mL, respectively) compared with before treatment (79.4 ± 9.0 kg; 94.4 ± 8.0 cm; and 5881 ± 3526 pg/mL, respectively). Significant increases in fecal levels of fatty acid metabolites (10-hydroxy-cis-12-octadecenoic acid, 10-oxo-cis-12-octadecenoic acid, and 10-oxo-trans-11-octadecenoic acid) were detected. Meanwhile, no significant changes were found in abdominal computed tomography parameters, blood marker levels, or short-chain fatty acid levels in the feces. Gut microbiota analysis revealed that some study subjects had decreased abundance of Firmicutes, increased abundance of Bacteroidetes, and increased α-diversity indices (Chao1 and ACE) after 8 weeks of treatment. The levels of Lactobacillus genus and Lactobacillus gasseri were significantly higher after 8 weeks of treatment. None of the subjects discontinued treatment or experienced severe adverse events. This study suggested that orlistat might alter gut microbiota composition and affect the body through fatty acid metabolites produced by the modified gut bacteria.

Active Consumption of Konjac and Konjac Products Improves Blood Glucose Control in Patients with Type 2 Diabetes Mellitus.

OBJECTIVE: Konjac is a food mainly consumed in Asian countries with high fiber and low energy. Although glucomannan, a component of konjac, have been used for several clinical studies, there is few reports using konjac itself. This study examined the effects of the active consumption of konjac in patients with type 2 diabetes mellitus (T2DM). METHODS: The study included 26 Japanese patients with T2DM. Participants were recommended to take konjac at least once a day using free konjac products (various noodles, rice, and desserts) and plate konjac for 12 weeks. RESULTS: HbA1c and fasting plasma glucose levels significantly decreased from 8.3 ± 0.9% to 8.0 ± 0.8% and from 173.2 ± 44.4 to 152.8 ± 36.7 mg/dL, respectively. No significant changes were observed in body weight and insulin resistance indices, but the index for insulin secretion significantly increased. Serum high molecular weight adiponectin levels significantly increased. Plasma ghrelin, leptin and glucagon-like peptide-1 levels tended to decrease (p = 0.084), decrease (p = 0.057) and increase (p = 0.071), respectively. Actual konjac intake positively correlated with age (r = 0.61, p = 0.001). Body weight and HbA1c significantly decreased in patients aged ≥50 years than in those aged <50 years, and the changes significantly inversely correlated with age. CONCLUSION: Active consumption of konjac and konjac products seems to be a useful dietary therapy with multifaceted action for T2DM. Further studies with greater sample size and long-term are needed to confirm these findings.

Current status of diabetes treatment in Miyazaki Prefecture, Japan: Results of a questionnaire survey conducted in 2016 and 2020.

AIMS/INTRODUCTION: The Japanese diabetes treatment guidelines do not specify the first choice of hypoglycemic agents, unlike those of Western countries. Furthermore, the current situation in diabetes treatment is that the choice of hypoglycemic agents is determined by each physician. Therefore, we aimed to determine the current situation in Miyazaki Prefecture, Japan, in this context. For this, we carried out a questionnaire survey among physicians twice regarding the target value of glycated hemoglobin and the choice of hypoglycemic agents in various cases. MATERIALS AND METHODS: We administered an unsigned questionnaire to physicians in Miyazaki Prefecture, Japan, in July 2016 and March 2020. We divided responses into those of diabetologists and those of non-diabetologists, and analyzed each response. We then compared the results between both years. RESULTS: In total, 18 diabetologists and 142 non-diabetologists responded in 2016, and 21 diabetologists and 134 non-diabetologists responded in 2020. Many diabetologists chose biguanide as the first-line drug for obese type 2 diabetes patients. In addition, the rate of choice of sodium-glucose cotransporter 2 inhibitor (SGLT2i) among physicians almost increased in 2020. Some non-diabetologists, and even a few diabetologists, inappropriately chose SGLT2i and biguanide for patients with severe renal dysfunction. CONCLUSIONS: Because SGLT2i became available in 2016 and a few years have passed, both diabetologists and non-diabetologists seemed to refrain from prescribing SGLT2i. However, with the emergence of various lines of firm evidence regarding the use of SGLT2i, physicians started to prescribe it. However, some diabetologists and non-diabetologists chose hypoglycemic agents inadequately; therefore, there is a need for novel and precise information.