Performing Roux-N Y Gastric Bypass on Rabbits: Perspective Report to Evaluate Body Weight Changes Food Consumption, And the Malabsorption of Vitamin D3

Al Meanazel, O.; Alanazi, F. K.; Hailat, M.; Abu Dayyih, W.; Al-Shdefat, R.; Abu Assab, M.; Awad, R.; Al-Ani, I.; Shakeel, F.; Alshora, D. H.; Ibrahim, M. A.

doi:10.1101/2023.01.20.524848

bioRxiv · 10.1101/2023.01.20.524848

Performing Roux-N Y Gastric Bypass on Rabbits: Perspective Report to Evaluate Body Weight Changes Food Consumption, And the Malabsorption of Vitamin D3

Al Meanazel, O.·Alanazi, F. K.·Hailat, M.·Abu Dayyih, W.·Al-Shdefat, R.·Abu Assab, M.·Awad, R.·Al-Ani, I.·Shakeel, F.·Alshora, D. H.·Ibrahim, M. A.

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Abstract

In 1998, Dr. Scopinaro published the first-ever known bariatric surgery, followed by reports by Buchwald and Oien in 2003 and 2013 [1,2]. Bariatric surgery (BS) is the most effective therapy against obesity, and recently it was recommended for type 2 diabetes as a therapeutic plan [3]. BS includes; Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy, and laparoscopic adjustable gastric banding has gained the attention of most healthcare providers in elevation of the issue of obesity for its ease and fast results, especially with patients with mobility problems and those with high risk to develop chronic diseases [1,2]. Gastric bypass is considered the most common BS and a gold standard for weight loss, also known as Roux-en-Y gastric bypass (RYGB). The procedure of this BS is by creating a small pouch of the stomach (300 mL capacity) connected directly to the jejunum by bypassing the duodenum. RYGB has many advantages, such as; the alteration of guts hormones, which reduces appetite and hunger feeling, increases energy expenditure, causes significant long-term weight loss (60-80% of the excess body weight), decreases the amount of food consumed, and preserves 50% of the weight loss during this procedure. However, RYGB has some disadvantages. The most critical issue regarding this BS is altering the absorption of many medicines and nutrients, such as; vitamin D3 (Vit D3) [4,5]. (American Society for Metabolic and Bariatric Surgery. Bariatric Surgery Procedures. https://asmbs.org/patients/bariatric-surgery-procedures (accessed Feb 15, 2020). RYGB was performed on rodents before [6] but was never applied to rabbits. To determine the malabsorption procedure after the RYGB, the pharmacokinetics of the substance must be attained, and data must be calculated, such as; Cmax and Tmax, to determine the absorption mutation. It was reported that pharmacokinetic studies on rodents could not be accurate due to the erratic absorption of the rodents [7]; thus, many studies have suggested using larger animals, such as rabbits, that do not address the same problem [8]. The current study investigates the ability to perform RYGB on rabbits and tests the effect of the surgery on body weight, food consumption, and the absorption of Vit D3.

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Al Meanazel, O., Alanazi, F. K., Hailat, M., Abu Dayyih, W., Al-Shdefat, R., Abu Assab, M., Awad, R., Al-Ani, I., Shakeel, F., Alshora, D. H., Ibrahim, M. A.. 2023-01-21. Performing Roux-N Y Gastric Bypass on Rabbits: Perspective Report to Evaluate Body Weight Changes Food Consumption, And the Malabsorption of Vitamin D3. https://doi.org/10.1101/2023.01.20.524848

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