The Gut-Brain Axis: Influence of Microbiota on Mood and Mental Health.

The gut-brain axis is a bidirectional communication network that links the enteric and central nervous systems. This network is not only anatomical, but it extends to include endocrine, humoral, metabolic, and immune routes of communication as well. The autonomic nervous system, hypothalamic-pituitary-adrenal (HPA) axis, and nerves within the gastrointestinal tract, all link the gut and the brain, allowing the brain to influence intestinal activities, including activity of functional immune effector cells; and the gut to influence mood, cognition, and mental health.

Pharmacokinetics and distribution of [35S]methylsulfonylmethane following oral administration to rats.

Methylsulfonylmethane (MSM) is a sulfur-containing compound found in a wide range of human foods including fruits, vegetables, grains, and beverages. More recently, it has been marketed as a dietary supplement worldwide. The objective of this study was to evaluate the pharmacokinetic profile and distribution of radiolabeled MSM in rats. Male Sprague-Dawley rats were administered a single oral dose of [35S]MSM (500 mg/kg), and blood levels of radioactivity were determined at different time points for up to 48 h. Tissue levels of radioactivity at 48 and 120 h and urine and fecal radioactivity levels were measured at different time points for up to 120 h following [35S]MSM administration to rats. Oral [35S]MSM was rapidly and efficiently absorbed with a mean tmax of 2.1 h, Cmax of 622 microg equiv/mL, and AUC0-inf of 15124 h.microg equiv/mL. The t1/2 was 12.2 h. Soft tissue distribution of radioactivity indicated a fairly homogeneous distribution throughout the body with relatively lower concentrations in skin and bone. Approximately 85.8% of the dose was recovered in the urine after 120 h, whereas only 3% was found in the feces. No quantifiable levels of radioactivity were found in any tissues after 120 h, indicating complete elimination of [35S]MSM. The results of this study suggest that [35S]MSM is rapidly absorbed, well distributed, and completely excreted from the body.

Arginine: Clinical potential of a semi-essential amino acid..

Arginine, a semi-essential amino acid, is involved in numerous areas of human biochemistry, including ammonia detoxification, hormone secretion, and immune modulation. Arginine is also well known as a precursor to nitric oxide (NO), a key component of endothelial-derived relaxing factor, an endogenous messenger molecule involved in a variety of endothelium-dependent physiological effects in the cardiovascular system. Because of arginine's NO-stimulating effects, it can be utilized in therapeutic regimens for angina pectoris, congestive heart failure, hypertension, coronary heart disease, preeclampsia, intermittent claudication, and erectile dysfunction. In addition, arginine has been studied in the treatment of HIV/AIDS, athletic performance, burns and trauma, cancer, diabetes and syndrome X, gastrointestinal diseases, male and female infertility, interstitial cystitis, immunomodulation, and senile dementia. Toxicity, dosage considerations, and contraindications are also reviewed.