EricMM
Well-known member
This study is using muscle wasting, which isn't exactly apples to apples but it shows that over 4 days HMB at 25% of the dose of Leucine was more effective than Leucine by 60%. So, maybe it's time to look back at HMB as a potential recovery agent.
Nutrition. 2014 Jul-Aug;30(7-8):807-13. doi: 10.1016/j.nut.2013.11.012. Epub 2013 Dec 4.
Comparison of the anticatabolic effects of leucine and Ca-β-hydroxy-β-methylbutyrate in experimental models of cancer cachexia.
Mirza KA1, Pereira SL2, Voss AC2, Tisdale MJ3.
Author information
Abstract
OBJECTIVE:
Loss of skeletal muscle is the most debilitating feature of cancer cachexia, and there are few treatments available. The aim of this study was to compare the anticatabolic efficacy of L-leucine and the leucine metabolite β-hydroxy-β-methylbutyrate (Ca-HMB) on muscle protein metabolism, both in vitro and in vivo.
METHODS:
Studies were conducted in mice bearing the cachexia-inducing murine adenocarcinoma 16 tumor, and in murine C2 C12 myotubes exposed to proteolysis-inducing factor, lipopolysaccharide, and angiotensin II.
RESULTS:
Both leucine and HMB were found to attenuate the increase in protein degradation and the decrease in protein synthesis in murine myotubes induced by proteolysis-inducing factor, lipopolysaccharide, and angiotensin II. However, HMB was more potent than leucine, because HMB at 50 μM produced essentially the same effect as leucine at 1 mM. Both leucine and HMB reduced the activity of the ubiquitin-proteasome pathway as measured by the functional (chymotrypsin-like) enzyme activity of the proteasome in muscle lysates, as well as Western blot quantitation of protein levels of the structural/enzymatic proteasome subunits (20 S and 19 S) and the ubiquitin ligases (MuRF1 and MAFbx). In vivo studies in mice bearing the murine adenocarcinoma 16 tumor showed a low dose of Ca-HMB (0.25 g/kg) to be 60% more effective than leucine (1 g/kg) in attenuating loss of body weight over a 4-d period.
CONCLUSION:
These results favor the clinical feasibility of using Ca-HMB over high doses of leucine for the treatment of cancer cachexia.
Nutrition. 2014 Jul-Aug;30(7-8):807-13. doi: 10.1016/j.nut.2013.11.012. Epub 2013 Dec 4.
Comparison of the anticatabolic effects of leucine and Ca-β-hydroxy-β-methylbutyrate in experimental models of cancer cachexia.
Mirza KA1, Pereira SL2, Voss AC2, Tisdale MJ3.
Author information
Abstract
OBJECTIVE:
Loss of skeletal muscle is the most debilitating feature of cancer cachexia, and there are few treatments available. The aim of this study was to compare the anticatabolic efficacy of L-leucine and the leucine metabolite β-hydroxy-β-methylbutyrate (Ca-HMB) on muscle protein metabolism, both in vitro and in vivo.
METHODS:
Studies were conducted in mice bearing the cachexia-inducing murine adenocarcinoma 16 tumor, and in murine C2 C12 myotubes exposed to proteolysis-inducing factor, lipopolysaccharide, and angiotensin II.
RESULTS:
Both leucine and HMB were found to attenuate the increase in protein degradation and the decrease in protein synthesis in murine myotubes induced by proteolysis-inducing factor, lipopolysaccharide, and angiotensin II. However, HMB was more potent than leucine, because HMB at 50 μM produced essentially the same effect as leucine at 1 mM. Both leucine and HMB reduced the activity of the ubiquitin-proteasome pathway as measured by the functional (chymotrypsin-like) enzyme activity of the proteasome in muscle lysates, as well as Western blot quantitation of protein levels of the structural/enzymatic proteasome subunits (20 S and 19 S) and the ubiquitin ligases (MuRF1 and MAFbx). In vivo studies in mice bearing the murine adenocarcinoma 16 tumor showed a low dose of Ca-HMB (0.25 g/kg) to be 60% more effective than leucine (1 g/kg) in attenuating loss of body weight over a 4-d period.
CONCLUSION:
These results favor the clinical feasibility of using Ca-HMB over high doses of leucine for the treatment of cancer cachexia.