Effects of Orlistat/Phentermine versus Phentermine on Vascular Endothelial Cell Function in Obese and Overweight Adults: A Randomized, Double-Blinded, Placebo-Controlled Trial

Orlistat and metformin combination ameliorates obesity-induced renal injury via suppressing renal oxidative stress in male rats

BACKGROUND

Orlistat (ORS) and metformin (MEF) are robustly used as well-established clinical drugs for the treatment for both obesity and the consequences of diabetes mellitus. Additionally, no study has been conducted to explore the consequence of the combination of both ORS and MEF on the kidneys of rats with obesity-induced renal injury (OBS).

OBJECTIVES

Therefore, the objective of the current research was designed to explore the possible ameliorative effects of either ORS and/or MEF or their combination against obesity (OBS) induced experimental renal oxidative stress.

METHODS

Renal oxidative stress was investigated at redox histopathological and immunohistological points in the kidney tissues.

RESULTS

The levels of urea, uric acid, and creatinine increased with the obesity effect; in addition, the myeloperoxidase (MPO) and xanthine oxidase (XO) activators were elevated significantly with the induction of OBS. The levels of non-enzymatic antioxidants (glutathione and thiol) declined sharply in OBS rats as compared to the normal group.

CONCLUSION

The data displayed that the combination of both ORS and MEF declined the obesity effects significantly by reducing the level of peroxidation (MDA), and enhancement intracellular antioxidant enzymes. These biochemical findings were supported by histopathology, immunohistochemistry, and Masson-Trichrome evaluation, which showed minor morphological changes in the kidneys of rats.

Pancreatic lipase and its related proteins: where are we now?

Obesity is a disease of epidemic proportions, with a worrisome upward trend. The high consumption of lipids, a major energy source, leads to obesity because of their high calorific value. Pancreatic lipase (PTL), produced by pancreatic acinar cells, hydrolyzes 50-70% of triacylglycerol (TAG) from food. PTL-related protein 1 (PLRP1) and 2 (PLRP2) are also produced by these cells. In vertebrates, PLRP1 has relatively less lipolytic activity, whereas PLRP2 has an essential role in lipid digestion, especially in infants. In this review, we summarize the structure and function of PTL, PLRP1, and PLRP2, and the metabolic fate of PTL inhibitors. We also discuss the current status of clinical trials on orlistat and its combinations for obesity treatment.

The Effect of Orlistat on Sterol Metabolism in Obese Patients

BACKGROUND

Orlistat, a reversible inhibitor of pancreatic and gastric lipase, is known to have anti-obesity and antioxidant properties. Cholesterol intermediates and metabolites have diverse and important functions in cardiovascular disease. Therefore, we aimed to evaluate the effect of orlistat on sterol metabolism in overweight and obese adults after weight loss during the intervention or weight loss at 12 weeks.

METHODS

A total of 51 (27 in the control group and 24 in the experimental group), patients with a BMI of 27 or greater were randomly assigned in a 1:1 ratio to receive either orlistat (120 mg) three times a day plus phentermine hydrochloride (37.5 mg) once daily or a placebo three times a day plus phentermine hydrochloride (37.5 mg) once daily. The primary study outcome was sterol metabolism.

RESULTS

The experimental group exhibited significantly decreased metabolic signatures of serum sterols, free cholesterol, sitosterol, 7α-hydroxycholesterol (7α-OHC), and 7β-OHC at 12 weeks. The experimental group also exhibited significantly decreased metabolic ratios of sitosterol and 7α-OHC to cholesterol at 12 weeks. Regarding changes in sterol signatures from baseline to 6-month follow-up, free cholesterol, plant sterols, and cholesterol precursors tended to decrease with weight loss during the intervention and increase again as the weight was regained in both groups.

CONCLUSION

Orlistat treatment improves oxysterol metabolism in overweight and obese adults. Our findings support that orlistat plays a crucial role in the process of endothelial dysfunction and atherosclerosis via oxysterol modulation.