X-Message-Number: 27860 Date: Fri, 21 Apr 2006 11:06:20 -0700 (PDT) From: Doug Skrecky <> Subject: nicotinamide may slow human aging [Nicotinamide is toxic to yeast and nematodes, via downregulation of SIR2. However genetic variation of SIR2 has no effect on drosophila longevity. The benefits of nicotinamide in human cells provides evidence that the biochemical basis of aging is different for humans. Indeed knockdown of SIRT1, an analog of SIR2 actually increases both mouse and human cell lifespan. Such diverse responses to silent information regulators indicate that the biochemistry of aging is diverse, and that non-mammalian animals can not be used to model mammalian aging.] Transplant Proc. 2003 Aug;35(5):2021-3. Nicotinamide induces both proliferation and differentiation of embryonic stem cells into insulin-producing cells. In contrast to the consistent observation that methods that promote proliferation also dedifferentiate insulin-producing cells, useful in vitro differentiation protocols must drive both proliferation and differentiation. We herein describe an strategy in which the combination of nutrient restriction and nicotinamide supplementation results in a consistent increase in the mass of insulin-producing cells. Mech Ageing Dev. 2006 Mar 14; [Epub ahead of print] Nicotinamide extends the replicative life span of primary human cells. [Niacinamide is another name for nicotinamide. This is the amide of nicotinic acid or niacin.] Dermatol Surg 2005; 31:860-865 Niacinamide: A B vitamin that improves aging facial skin appearance. Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=27860