Methylcobalamin effects on diabetic neuropathy and nerve protein kinase C in rats

Abstract

This study suggested that correction of impaired neural signalling of PKC and oxidative stress-induced damage may be a major attribute to the beneficial effects of MC on diabetic nerve.

Triglyceride, nonesterified fatty acids, and prediabetic neuropathy: role for oxidative–nitrosative stress

“…Furthermore, experimental studies in streptozotocin-diabetic rats [83, 84] and a small open-label clinical trial [85] with another niacin derivative, niceritrol, demonstrated reduction of serum triglyceride concentration and alleviation of peripheral neuropathy, in the absence of amelioration of diabetic hyperglycemia. This apparent similarity of action between niacin (vitamin B3)/its derivatives and other B vitamins is not surprising because niacin [85], its derivative acipimox in the current study, and other afore-mentioned B vitamins [82, 86, 87] counteract oxidative-nitrosative stress. Note, however, that only niacin and its derivatives, but not other B vitamins, display potent hypolipidemic activity.…”

“…In previous studies, several B vitamins i.e., thiamine (B 1 ), pyridoxine (B 6 ), and methylcobalamin (B 12 ), ameliorated diabetes-induced peripheral nerve dysfunction [80–82]. Furthermore, experimental studies in streptozotocin-diabetic rats [83, 84] and a small open-label clinical trial [85] with another niacin derivative, niceritrol, demonstrated reduction of serum triglyceride concentration and alleviation of peripheral neuropathy, in the absence of amelioration of diabetic hyperglycemia.…”

High glucose upregulates CYP24A1 expression which attenuates the ability of 1,25(OH)2D3 to increase NGF secretion in a rat Schwann cell line RSC96

“…As all know that the pathogenesis of DPN has been caused by a number of metabolic abnormalities including polyol pathway hyperactivity, increased advanced glycation end-point formation, alterations in the protein kinase C pathway and reduced supply of neurotrophic factors (Dobrowsky et al, 2005;Mizukami et al, 2011;Obrosova et al, 2007;Song et al, 2003). In particular, aldose reductase, the first enzyme in the polyol pathway, is localized in Schwann cells in the peripheral nervous system (Kern and Engerman, 1982).…”

Research update for articles published in EJCI in 2011

“…Methylcobalamin effects on diabetic neuropathy and nerve protein kinase C (PKC) in rats [52] (Soroku Yagihashi and Hiroki Mizukami)…”