Serum prohepcidin levels are lower in patients with atrophic gastritis

Dual role of hepcidin in response to pathogens

Hepcidin is the primary regulator of vertebrate iron homeostasis. Its production is stimulated by systemic iron levels and inflammatory signals. Although the role of hepcidin in iron homeostasis is well characterized, its response to pathogenic agents is complex and diverse. In this review, we examine studies that investigate the role of hepcidin in response to infectious agents. Interleukin-6 (IL-6) is a key factor responsible for the induction of hepcidin expression. During infection, hepcidin-mediated depletion of extracellular iron serves as a protective mechanism against a variety of pathogens. However, accumulation of iron in macrophages through hepcidin-mediated pathways may increase susceptibility to intracellular pathogens such as Mycobacterium tuberculosis. Prolonged elevation of hepcidin production can lead to anemia due to reduced iron availability for erythropoiesis, a condition referred to as anemia of inflammation. In addition, we highlight the role of hepcidin upregulation in several infectious contexts, including HIV-associated anemia, iron deficiency anemia in Helicobacter pylori infection, and post-malarial anemia in pediatric patients. In addition, we show that certain infectious agents, such as hepatitis C virus (HCV), can suppress hepcidin production during both the acute and chronic phases of infection, while hepatitis B virus (HBV) exhibits similar suppression during the chronic phase.

High Hepcidin Levels Promote Abnormal Iron Metabolism and Ferroptosis in Chronic Atrophic Gastritis

BACKGROUND

Chronic atrophic gastritis (CAG) is a chronic inflammatory disease and premalignant lesion of gastric cancer. As an antimicrobial peptide, hepcidin can maintain iron metabolic balance and is susceptible to inflammation.

OBJECTIVES

The objective of this study was to clarify whether hepcidin is involved in abnormal iron metabolism and ferroptosis during CAG pathogenesis.

METHODS

Non-atrophic gastritis (NAG) and chronic atrophic gastritis (CAG) patient pathology slides were collected, and related protein expression was detected by immunohistochemical staining. The CAG rat model was established using MNNG combined with an irregular diet.

RESULTS

CAG patients and rats exhibited iron deposition in gastric tissue. CAG-induced ferroptosis in the stomach was characterized by decreased GPX4 and FTH levels and increased 4-HNE levels. Hepcidin, which is mainly located in parietal cells, was elevated in CAG gastric tissue. The high gastric level of hepcidin inhibited iron absorption in the duodenum by decreasing the protein expression of DMT1 and FPN1. In addition, the IL-6/STAT3 signaling pathway induced hepcidin production in gastric tissue.

CONCLUSION

Our results showed that the high level of gastric hepcidin induced ferroptosis in the stomach but also inhibited iron absorption in the intestines. Inhibiting hepcidin might be a new strategy for the prevention of CAG in the future.

Low PG I/II ratio as a marker of atrophic gastritis: Association with nutritional and metabolic status in healthy people

A low pepsinogen (PG) I/II ratio can be used to detect atrophic gastritis (AG). Recent research has found that the PG I/II ratio is associated with several nutritional and metabolic disorders. The aim of this study is to investigate the relationship between the PG I/II ratio and biochemical markers in a Chinese population.In total, 1896 participants in a gastric cancer screening program underwent a health screening test that included assessment of serum pepsinogens. Subjects with PG I/II < 3.0 were considered as having atrophic gastritis. Associations between the PG I/II ratio and biochemical markers reflecting glucose and lipid metabolism, liver, kidney and thyroid functions were evaluated using SPSS software version 20.The prevalence of atrophic gastritis was 5.3% and increased with age but did not differ between sexes. Albumin, ferritin, and total and direct bilirubin were significantly lower in patients with AG than in those without AG, whereas age, total bile acid, and amylase were significantly higher. Albumin, ferritin, and triglyceride correlated positively with the PG I/II ratio, while age, total bile acid, blood urea nitrogen, amylase, aspartate aminotransferase, creatine kinase, and lactate dehydrogenase correlated inversely with the PG I/II ratio. Logistic regression analysis demonstrated that age, total bile acid, total protein, and ferritin correlated independently with AG.Low PG I/II ratio is not only a marker of atrophic gastritis but also an indicator of nutritional and metabolic status. Special attention should be paid to the metabolism of iron, protein, and bile acid in patients with a low PG I/II ratio.

Helicobacter pylori and extragastric diseases

While Helicobacter pylori infection was initially revealed to be associated only with some gastroduodenal diseases, further studies have shown its possible role in several extragastric diseases. For idiopathic thrombocytopenic purpura, sideropenic anemia, and vitamin B12 deficiency, the diagnosis of H. pylori infection is recommended, and there are many other conditions such as cardiovascular, neurological, dermatological, and respiratory diseases in which H. pylori may possibly play a role. Interestingly, a potential role has also been described for GI neoplastic diseases, including colorectal and pancreatic cancer. Different mechanisms of action have been proposed, ranging from the induction of a low grade inflammatory state to the occurrence of molecular mimicry mechanisms. This review summarizes the results of the most relevant studies published on this topic over the last year.