Author: Gianpiero Pescarmona
HO-1 is inducible by the same factors that induce COX-2 and iNOS
Heme Oxygenase-1 Gene Promoter Polymorphism is Associated with Risk of Gastric Adenocarcinoma and Lymphovascular Tumor Invasion.
Central CO-heme oxygenase pathway raises body temperature by a prostaglandin-independent way.
Effects of nitrogen monoxide and carbon monoxide on molecular and cellular iron metabolism 2003
Involvement of the Heme Oxygenase–Carbon Monoxide Pathway in Keratinocyte Proliferation
Biliverdin and more
Choleretic Effect of licorice
Hyperbilirubinemia Protects against Aging-Associated Inflammation and Metabolic Deterioration, 2016
Compared to their normobilirubinemic siblings, aged hyperbilirubinemic Gunn rats showed significantly smaller amounts of visceral fat, better glucose tolerance, and decreased serum levels of proinflammatory cytokines TNFα, IL-1β, and IL-18. Simultaneously, livers from Gunn rats showed decreased expression of senescence markers and cell cycle inhibitors p21 and p16.
Marta Lepora - Sara Rossi
CO as vasodilator
Glucagon and heme - oxydase
A possible mechanism that may be advanced to account for the positive relationship between fasting or hypoglycemia and the rise in serum bilirubin, is enhancement of bilirubin formation from increased heme turnover in the liver. In fact some studies about hepatic HO activity in rats show that HO activity increases progressively, reaching approximately 3 times the control value after 72 hours of fasting.
A study valuates HO activity in relation with some hormones that are enhanced during hypoglycemia and starvation and reduced after meals: glucagon, insulin, epinephrine, arginine (which triggers the release of endogenous glucagon). The results of this study are below.
Glucagon injection doubled the hepatic HO activity, while splenic HO activity remained unaffected (Table II). Glucose given together with glucagon did not abolish the stimulatory effect of the hormone (Table II). In animals whose hepatic HO had been stimulated by 48 hr fasting, glucagon had no additional effect on the enzyme activity (Fig. 2). However, on prolonged starvation, glucagon given at 72 and 92 hr doubled and tripled HO activity as compared to that in untreated rats fasted for the same length of time. Arginine, caused a fivefold increase in hepatic HO activity (Table II). This rise in activity exceeded the enzyme stimulation obtained with individual glucagon injections at 7 and 5, or 5 and 3 hr before assay (Table II). Epinephrine (0.1 mg/100 g rat) and glucagon (1 mg/100 g rat) given together in two i.p. injections 7 and 5 hr before enzyme assay produced additive enhancement of hepatic enzyme activity (Table II)
Insulin-induced hypoglycemia was associated with an increase in hepatic HO activity that was similar to that seen in fasted animals (Table I). This stimulatory effect of insulin was blunted or abolished when the injected insulin was "covered" with glucose administered simultaneously (Table I), which indicates that insulin by itself does not stimulate the enzyme.
link Metabolic Regulation of Heme Catabolism and Bilirubin Production I. HORMONAL CONTROL OF HEPATIC HEME OXYGENASE ACTIVITY.
TABLE I: Hepatic Heme Oxygenase Activity: Effect of Hypoglycemia