Monday, July 7, 2014

Betaine mitigates the destabilizing effect of protein crowding

Most theories predict that macromolecular crowding stabilizes globular proteins, but recent studies show that weak attractive interactions can result in crowding-induced destabilization. Osmolytes are ubiquitous in biology and help protect cells against stress. Given that dehydration stress adds to the crowded nature of the cytoplasm, we speculated that cells might use osmolytes to overcome the destabilization caused by the increased weak interactions that accompany desiccation. We used NMR-detected amide proton exchange experiments to measure the stability of the test protein chymotrypsin inhibitor 2 under physiologically relevant crowded conditions in the presence and absence of the osmolyte glycine betaine. The osmolyte overcame the destabilizing effect of the cytosol. This result provides a physiologically relevant explanation for the accumulation of osmolytes by cells stressed by dehydration.

Sarkar, M. and G.J. Pielak, An osmolyte mitigates the destabilizing effect of protein crowding. Protein Sci, 2014

Anti-inflammatory effects of betaine on AOM/DSS induced colon tumorigenesis in ICR male mice

Betaine is an important human nutrient obtained from various foods and studies in animals and humans have provided results suggesting their pathogenesis of various chronic diseases and points to a role in risk assessment and disease prevention. However, the molecular mechanisms of its activity remain poorly understood and warrant further investigation. This study was performed to investigate the anti-inflammation and tumor preventing capacity of betaine on colitis-associated cancer in mice. In in vivo experiments, we induced colon tumors in mice by azoxymethane (AOM) and dextran sulfate sodium (DSS) and evaluated the effects of betaine on tumor growth. Administration with betaine significantly decreased the incidence of tumor formation with downregulation of inflammation. Treatment with betaine inhibited ROS generation and GSSG concentration in colonic mucosa. Based on the qPCR data, administration of betaine inhibited inflammatory cytokines such TNF-alpha, IL-6, iNOS and COX-2. In in vitro experiments, LPS-induced NF-kappaB and inflammatory-related cytokines were inhibited by betaine treatment in RAW 264.7 murine macrophage cells. Our findings suggest that betaine is one of the candidates for the prevention of inflammation-associated colon carcinogenesis.

Kim, D.H., et al., Anti-inflammatory effects of betaine on AOM/DSSinduced colon tumorigenesis in ICR male mice. Int J Oncol, 2014. 45(3): p. 1250-6

Betaine is a potential agent for the treatment of hepatopathy associated with short bowel syndrome

Background: The hepatopathy associated with short bowel syndrome (SBS) is a multifactorial disease associated with poor prognosis. Besides intestinal transplantation, no other treatment has been shown effective. The current study evaluated the efficacy of betaine for the treatment of hepatopathy associated with SBS.
Methods: A prospective, unicentric, non-placebo controlled trial was carried out. After initial evaluation, 10g of betaine anhydrous was administrated to SBS patients in two divided doses for three months. The hepatic steatosis was assessed through nuclear magnetic resonance (NMR), the inflammatory response by interleukin- 6 (IL-6), tumor necrosis factor-(TNF-) and ferritin, besides the hepatic lesion through hepatic enzymes and bilirubin. Furthermore, the effect of betaine on homocysteine was evaluated as well as its safety and tolerability in this group of patients.
Results: After three months supplementation, patients showed decreased percentage of hepatic fat (p = 0.03) through triphasic NMR examination. There was no significant reduction of serum levels for inflammatory proteins and hepatic lesion markers. Homocysteinemia also did not present significant decrease. The most prevalent side effects were diarrhea and nausea, reported in 62% of the participants; however, these symptoms were transient and not severe enough to justify the treatment interruption. Parenteral nutrition-dependent patients did not present different hepatic lesion degree compared to patients who do not need the prolonged use of it.
Conclusions: Betaine was shown to be a potential agent for the treatment of hepatopathy associated with SBS, which was evidenced by NMR, although the markers for hepatic lesion have not presented significant decrease.

Teixeira Araujo, G., et al., Betaine: A Potential Agent for the Treatment of Hepatopathy Associated with Short Bowel Syndrome. Nutr Hosp, 2014. 29(n06): p. 1366-1371

The effect of dietary alpha-lipoic acid, betaine, l-carnitine, and swimming on the obesity of mice induced by a high-fat diet

We evaluate the effect of supplementation, at 300 mg kg-1 body weight (BW), with the antioxidants alpha-lipoic acid (AL), betaine (BT), l-carnitine (LC), and the combination of these and exercise on obesity induced by a 9 week high-fat diet (HFD) in mice. Healthy 5 week-old male C57BL/6J mice were divided into 9 groups: (1) CON, control group fed with a commercial mice chow containing 10% crude fat; (2) HFD, high fat diet group fed with a commercial mice chow containing 60% crude fat; (3) HFD-AL, HFD group fed with AL; (4) HFD-BT, HFD group fed with BT; (5) HFD-LC, HFD group fed with LC; (6) HFD-SW, HFD with swimming as an exercise; (7) HFD-SWAL, HFD-AL with swimming; (8) HFD-SWBT, HFD-BT with swimming, and (9) HFD-SWLC, HFD-LC with swimming. The BW of mice with LC and swimming reduced the increase of BW after 9 weeks. Relative adipose tissue weights were reduced by the combinations of antioxidant supplementation and swimming. Levels of serum glucose and leptin were reduced in the HFD-SWLC group when compared with the HFD group. Serum triglyceride and total cholesterol and the size of adipose were also decreased in the HFD-LC and HFD-SWLC groups. These results show that LC at a dose of 300 mg kg-1 BW was the most effective for reducing fat accumulation in mice with HFD for 9 weeks. In addition, exercise should be given in combination to enhance the BW reduction and serum lipid level.

Jang, A., et al., The effect of dietary alpha-lipoic acid, betaine, l-carnitine, and swimming on the obesity of mice induced by a high-fat diet. Food Funct, 2014

Hepatoprotective effects of Lycium chinense Miller fruit and its constituent betaine in CCl-induced hepatic damage in rats.

The hepatoprotective activities of Lycium chinense Miller (LC) fruit extract and its component betaine were investigated under carbon tetrachloride (CCl4)-induced hepatotoxicity in rats. The treatment of LC fruit extract significantly suppressed the increase of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the sera of CCl4 injured rats, and restored the decreased levels of anti-oxidant enzymes such as total antioxidant capacity (TAC), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) and suppressed the expression of inflammatory mediators including inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-1 and -2. To visualize the potential activity of betaine, a component of LC fruit, betaine was substituted for LC extract in CCl4 injured rats. The biochemical profile in CCl4 injured rats co-treated with betaine matched those of LC fruit treated CCl4 injured rats. The ameliorative effects of LC extract, as well as betaine, were also confirmed by histopathological examination. Collectively, the present findings imply that LC fruit, via its component betaine, mitigate CCl4-induced hepatic injury by increasing antioxidative activity and decreasing inflammatory mediators including iNOS and COX-1/COX-2.

Ahn, M., et al., Hepatoprotective effects of Lycium chinense Miller fruit and its constituent betaine in CCl-induced hepatic damage in rats. Acta Histochem, 2014