Potential mediation effect of insulin resistance on the association between iron metabolism indicators and non-alcoholic fatty liver disease.

OBJECTIVES: Iron metabolism and insulin resistance (IR) are closely related to non-alcoholic fatty liver disease (NAFLD). However, the interplay between them on the occurrence and progression of NAFLD is not fully understood. We aimed to disentangle the crosstalk between iron metabolism and IR and explore its impact on NAFLD. METHODS: We analyzed data from the National Health and Nutritional Examination Survey (NHANES) 2017-2018 to evaluate the association between serum iron metabolism indicators (ferritin, serum iron, unsaturated iron-binding capacity [UIBC], total iron-binding capacity [TIBC], transferrin saturation, and transferrin receptor) and NAFLD/non-alcoholic steatohepatitis (NASH). Mediation analysis was conducted to explore the role of IR played in these relationship. RESULTS: A total of 4812 participants were included, among whom 43.7% were diagnosed with NAFLD and 13.2% were further diagnosed with NASH. After adjusting the covariates, the risk of NAFLD increases with increasing serum ferritin (adjusted odds ratio [aOR] 1.71, 95% confidence interval [CI] 1.37-2.14), UIBC (aOR 1.45, 95% CI 1.17-1.79), and TIBC (aOR 1.36, 95% CI 1.11-1.68). Higher levels of serum ferritin (aOR 3.70, 95% CI 2.25-6.19) and TIBC (aOR 1.69, 95% CI 1.13-2.56) were also positively associated with NASH. Participants with IR were more likely to have NAFLD/NASH. Moreover, IR-mediated efficacy accounted for 85.85% and 64.51% between ferritin and NAFLD and NASH, respectively. CONCLUSION: Higher levels of serum ferritin and TIBC are closely associated with the occurrence of NAFLD and NASH. IR may be considered a possible link between NAFLD or NASH and increased serum ferritin levels.

Prevalence of Kaposi's sarcoma-associated herpesvirus in Uygur and Han populations from the Urumqi and Kashgar regions of Xinjiang, China.

Kaposi's sarcoma-associated herpesvirus (KSHV) is the infectious etiologic agent associated with Kaposi's sarcoma (KS), primary effusion lymphoma, and multicentric Castleman disease. It has been shown that high KSHV prevalence and high incidence of both classic KS and AIDSassociated KS are found mostly among people of Uygur ethnicity in Xinjiang, while people of Han ethnicity in Xinjiang have a higher KSHV seroprevalence than those of other Han populations in mainland China. However, it is still unclear why there is such geographical and population variation in KSHV distribution in China. In this work, we focused on the populations in the Kashgar region and Urumqi area, where a total of 1294 research subjects were randomly selected to investigate the potential correlation between KSHV prevalence and different ethnicities in endemic areas of Xinjiang, and to determine risk factors that may affect KSHV infection rates or KS incidence. We identified a high seroprevalence of KSHV and high peripheral blood DNA infection in the general Uygur and Han populations in both Urumqi and Kashgar regions of Xinjiang, and determined that advancing age, low education level, and stationary population status affect KSHV infection rates. Further, KSHV-positive Uygur participants were shown to have higher prevalence of neutralizing antibodies and neutralizing antibody titers than KSHV-positive Han participants.

Calpain is involved in the HIV replication from the latently infected OM10.1 cells.

Treatment of OM10.1 cells latently infected with human immunodeficiency virus type 1 (HIV-1) with phorbol ester and calcium ionophore (A23187) induced virus replication which was blocked by N-Ac-Leu-Leu-norleucinal (ALLnL), a calpain inhibitor I, and not by lactacystin, a specific proteasome inhibitor. When the purified NF-kappa B/I kappa B complex was treated with mu-calpain, the specific DNA-binding activity was demonstrated by using electrophoretic mobility shift assay in vitro. This effect of mu-calpain was inhibited by ALLnL and calpastatin and not by lactacystin. In fact, we found that mu-calpain efficiently degraded I kappa B alpha. Furthermore, our Western blotting analysis has revealed that mu-calpain cleaves I kappa B alpha at its N-terminal and C-terminal regions that were previously reported to be involved in the interaction with NF-kappa B p65. These observations indicate that in monocyte/macrophage cells calcium signaling is involved in NF-kappa B activation through activation of calpain and thus calpain inhibitors may be effective in inhibiting the activation of latently infected HIV.